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1.
Clinics ; 76: e2348, 2021. graf
Artigo em Inglês | LILACS | ID: biblio-1153978

RESUMO

OBJECTIVES: TTP488, an antagonist of the receptor for advanced glycation end-products, was evaluated as a potential treatment for patients with mild-to-moderate Alzheimer's disease (AD). However, the mechanism underlying the protective action of TTP488 against AD has not yet been fully explored. METHODS: Healthy male rats were exposed to aberrant amyloid β (Aβ) 1-42. Lipopolysaccharide (LPS) and the NOD-like receptor family pyrin domain containing 1 (NLRP1) overexpression lentivirus were injected to activate the NLRP1 inflammasome and exacerbate AD. TTP488 was administered to reverse AD injury. Finally, tofacitinib and fludarabine were used to inhibit the activity of Janus tyrosine kinase (JAK) and signal transducer and activator of transcription (STAT) to prove the relationship between the JAK/STAT signaling pathway and TTP488. RESULTS: LPS and NLRP1 overexpression significantly increased the NLRP1 levels, reduced neurological function, and aggravated neuronal damage, as demonstrated by the impact latency time of, time spent by, and length of the platform covered by, the mice in the Morris water maze assay, Nissl staining, and immunofluorescence staining in rats with AD. CONCLUSIONS: TTP488 administration successfully reduced AD injury and reversed the aforementioned processes. Additionally, tofacitinib and fludarabine administration could further reverse AD injury after the TTP488 intervention. These results suggest a new potential mechanism underlying the TTP488-mediated alleviation of AD injury.


Assuntos
Animais , Masculino , Camundongos , Ratos , Janus Quinases/metabolismo , Doença de Alzheimer/tratamento farmacológico , Tirosina , Transdutores , Transdução de Sinais , Peptídeos beta-Amiloides , Janus Quinase 2 , Receptor para Produtos Finais de Glicação Avançada , Imidazóis
2.
Arq. Asma, Alerg. Imunol ; 4(3): 363-369, jul.set.2020. ilus
Artigo em Português | LILACS | ID: biblio-1382015

RESUMO

A pandemia pelo vírus SARS-CoV-2 atingiu adultos, crianças e penalizou indivíduos idosos e com comorbidades como diabetes, doença cardíaca, hipertensão e obesidade. A maioria dos infectados são assintomáticos ou têm sintomas leves, entretanto 15% podem apresentar pneumonia e 5% síndrome respiratória aguda grave. Apresentamos um caso de agamaglobulinemia ligada ao X (XLA) em paciente masculino de 27 anos que se infectou com SARS-CoV-2. Os pacientes com XLA não possuem linfócitos B e não produzem anticorpos devido a uma mutação no gene Bruton tirosino-quinase (BTK), responsável pela maturação dos linfócitos B. Ele infectou-se e foi internado em hospital de Ivoti/RS. A evolução da pneumonia foi rápida, necessitando transferência para o Hospital de Clínicas de Porto Alegre (HCPA) no 10° dia de evolução. Iniciou com infusão de imunoglobulinas, tendo utilizado o total de 400 gramas devido ao intenso catabolismo da IgG, mantendo-se sua concentração entre 700-900 mg/dL. Necessitou de ventilação mecânica, oxigenação por membrana extracorpórea (ECMO) e hemodiálise. Foi administrado plasma de convalescente (PC), 300 mL, por duas vezes, com melhora clínico-radiológica e retirada da ventilação mecânica. Piorou e repetiu outras 4 infusões de PC (total de 1717 mL), negativando o vírus na orofaringe (RT-PCR). Em 3 ocasiões teve sepse, debelada rapidamente. Apresentou anemia, com necessidade de transfusão frequente. Identificou-se linfopenia de CD3, CD4, CD8, NK e ausência de linfócitos B. A linfopenia foi revertida com a recuperação clínica e a alta hospitalar aconteceu no 70° dia de internação.


The SARS-CoV-2 pandemic has affected adults and children and penalized older people and those with comorbidities such as diabetes, heart disease, hypertension and obesity. Most of those infected are asymptomatic or have mild symptoms, but 15% may have pneumonia and 5% acute respiratory distress syndrome. We report a case of X-linked agammaglobulinemia (XLA) in a 27-yearold man who was infected with SARS-CoV-2. XLA patients do not have B lymphocytes and do not produce antibodies because of mutations in the Bruton tyrosine-kinase gene, responsible for the maturation of B cells. This patient was infected and then admitted to a hospital in Ivoti, southern Brazil. Pneumonia progressed rapidly, requiring transfer to the Hospital de Clínicas de Porto Alegre on the 10th day. Intravenous immunoglobulin infusions were initiated, using a total of 400 grams because of an intense catabolism of IgG, and the concentration was kept around 700- 900 mg/dL. Mechanical ventilation, extracorporeal membrane oxygenation and hemodialysis were necessary. Convalescent plasma (CP) was administered (2x300 mL) and then followed by clinical and radiological improvement and interruption of mechanical ventilation. Then he got sicker and had to return to invasive support and received 4 extra CP infusions (total of 1717 mL), until a negative reverse-transcriptase polymerase chain reaction (RT-PCR) for SARS-CoV-2 was obtained. On 3 occasions he had sepsis, promptly managed. He had anemia, requiring frequent transfusion, and lymphopenia (CD3, CD4, CD8, NK), with absence of B lymphocytes. Lymphopenia was reverted during recovery, and he was discharged from the hospital on the 70th day.


Assuntos
Humanos , Masculino , Adulto , Tirosina , Imunoglobulina G , Linfócitos B , Agamaglobulinemia , SARS-CoV-2 , COVID-19 , Plasma , Pneumonia , Respiração Artificial , Sinais e Sintomas , RNA Polimerases Dirigidas por DNA , Reação em Cadeia da Polimerase , Imunoglobulinas Intravenosas , Sepse , Síndrome Respiratória Aguda Grave
3.
J. bras. nefrol ; 42(3): 307-314, July-Sept. 2020. tab, graf
Artigo em Inglês, Português | LILACS | ID: biblio-1134843

RESUMO

ABSTRACT Background: Patients with chronic kidney disease (CKD) present an imbalance of the gut microbiota composition, leading to increased production of uremic toxins like p-cresyl sulfate (PCS), product from bacterial fermentation of the amino acids tyrosine (Tyr) and phenylalanine (Phe) from the diet. Thus, diet may be a determinant in the uremic toxins levels produced by the gut microbiota. The aim of this study was to evaluate the possible relationship between Tyr and Phe intake and PCS plasma levels in non-dialysis CKD patients. Methods: Twenty-seven non-dialysis CKD patients (stages 3 and 4) without previous nutritional intervention were evaluated. The dietary intake was evaluated using a 24-hour recall, 3-day food record and protein intake was also estimated by Protein Nitrogen Appearance (PNA). The plasma levels of PCS were measured using reverse phase high performance liquid chromatography. Results: The evaluated patients (GRF, 34.8 ± 12.4 mL/min, 54.2 ± 14.3 years, BMI, 29.3 ± 6.1 kg/m2) presented mean protein intake of 1.1 ± 0.5 g/kg/day), Tyr of 4.5 ± 2.4 g/day and Phe of 4.6 ± 2.5 g/day. PCS plasma levels (20.4 ± 15.5 mg/L) were elevated and positively associated with both, Tyr (r = 0.58, p = 0.002) and Phe intake (r = 0.53, p = 0.005), even after adjustments for eGFR and age. Conclusion: This study suggests that the diet is an important modulator of the uremic toxins plasma levels produced by the gut microbiota, in non-dialysis CKD patients.


RESUMO Introdução: Pacientes com doença renal crônica (DRC) apresentam desequilíbrio na composição da microbiota intestinal, gerando toxinas urêmicas, como o p-cresil sulfato (PCS), pela fermentação bacteriana dos aminoácidos tirosina (Tyr) e fenilalanina (Phe) da dieta. Assim, a dieta pode ser determinante nos níveis de toxinas urêmicas produzidos pela microbiota intestinal. O objetivo deste estudo foi avaliar a possível relação entre a ingestão de Tyr e Phe e os níveis plasmáticos de PCS em pacientes com DRC não dialisados. Métodos: Foram avaliados 27 pacientes com DRC em tratamento conservador (estágios 3 e 4), sem intervenção nutricional prévia. A ingestão alimentar foi avaliada pelo recordatório alimentar de 24h (R-24h) de 3 dias, e a ingestão proteica também foi verificada através do Protein Nitrogen Appearance (PNA). Os níveis plasmáticos de PCS foram determinados por cromatografia líquida de fase reversa. Resultados: Os pacientes avaliados (TFG, 34,8 ± 12,4 mL/min, 54,2 ± 14,3 anos, IMC 29,3 ± 6,1 kg/m2) apresentaram ingestão média de proteína de 1,1 ± 0,5 g/kg/dia, Tyr de 4,5 ± 2,4 g/dia e Phe de 4,6 ± 2,5 g/dia. Os níveis plasmáticos de PCS (20,4 ± 15,5 mg/L) foram elevados e positivamente associados à ingestão de Tyr (r = 0,58, p = 0,002) e Phe (r = 0,53, p = 0,005), mesmo após ajustes pela TFG e idade. Conclusão: Este estudo sugere que a dieta é um importante modulador dos níveis plasmáticos de toxinas urêmicas produzidas pela microbiota intestinal em pacientes com DRC não dialisados.


Assuntos
Humanos , Fenilalanina , Tirosina , Dieta , Insuficiência Renal Crônica , Indicã , Sulfatos , Ésteres do Ácido Sulfúrico , Cresóis , Ingestão de Alimentos
4.
Int. j. morphol ; 38(4): 919-923, Aug. 2020. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1124877

RESUMO

Letrozole (Letro) is a drug commonly used for breast cancer treatment since it can decrease estrogen level. In experimental animal, the Letro has been used to induce the polycystic ovarian syndrome (PCOS) model. Tyrosine phosphorylation (TyrPho) is an essential process in various biological functions both normal and abnormal conditions especially reproduction. Although some side effects of Letro are reported, the alterations of TyrPho responsible for liver and kidney functions have never been demonstrated. In this study, the blood serum, liver, and kidney of control and PCOS rats induced with Letro (orally, 1 mg/ KgBW) for consecutive 21 days were used to determine the serum biochemical components and to investigate the TyrPho expression using western blot analysis. Histopathology of such tissues was observed by Masson's trichrome staining. The results showed that Letro did not affect histological structures but significantly increased the serum levels of urea nitrogen, cholesterol, triglyceride, HDL, LDL, ALT, AST, and alkaline phosphatase. Additionally, the TyrPho protein expressions of 32 and 27 kDas in liver and of 55 and 43 kDas in kidney were increased while of a kidney 26 kDa was decreased as compared to those of control. In conclusion, this recent study indicated that the changes of TyrPho proteins in liver and kidney induced with Letro associated with their functions by alteration of serum biochemical levels.


El letrozol (Letro) es un medicamento utilizado comúnmente para el tratamiento del cáncer de mama, debido a que puede disminuir el nivel de estrógeno. En animales de experimentación, el Letro se ha utilizado para inducir el modelo de síndrome de ovario poliquístico (PCOS). La fosforilación de tirosina (TyrPho) es un proceso esencial en diversas funciones biológicas, tanto en condiciones normales como anormales, especialmente en la reproducción. A pesar de informes que indican algunos efectos secundarios de Letro, no se han demostrado las alteraciones de TyrPho responsables de las funciones hepáticas y renales. En este estudio, el suero sanguíneo, el hígado y el riñón control y las ratas PCOS inducidas con Letro (por vía oral, 1 mg / KgBW) durante 21 días consecutivos se usaron para determinar los componentes bioquímicos del suero y para investigar la expresión de TyrPho usando análisis de transferencia Western. La histopatología de los tejidos se observó mediante la tinción tricrómica de Masson. Los resultados mostraron que Letro no afectó las estructuras histológicas, pero aumentó significativamente los niveles séricos de urea, colesterol, triglicéridos, HDL, LDL, ALT, AST y fosfatasa alcalina. Además, las expresiones de la proteína TyrPho de 32 y 27 kDas en el hígado y de 55 y 43 kDas en el riñón aumentaron mientras que en un riñón disminuyeron 26 kDa en comparación con el control. En conclusión, este estudio indicó que los cambios de las proteínas TyrPho en el hígado y los riñones inducidos con Letro se asociaron con sus funciones mediante la alteración de los niveles bioquímicos en suero.


Assuntos
Animais , Feminino , Ratos , Síndrome do Ovário Policístico/induzido quimicamente , Letrozol/efeitos adversos , Rim/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fosforilação/fisiologia , Tirosina/metabolismo , Western Blotting , Ratos Wistar , Modelos Animais de Doenças , Eletroforese em Gel de Poliacrilamida
5.
Acta bioquím. clín. latinoam ; 54(2): 125-133, jun. 2020. graf, tab
Artigo em Espanhol | LILACS | ID: biblio-1130587

RESUMO

El objetivo del trabajo fue evaluar la utilidad clínica de la relación factor de crecimiento placentario/receptor de tirosin-quinasa tipo 1 soluble (sFlt-1/ PlGF) para el diagnóstico de preeclampsia (PE) en embarazadas de alto riesgo y con diagnóstico clínico de PE en un centro de salud de Córdoba, Argentina. Se procesaron 135 muestras de embarazadas: 39 con diagnóstico clínico de PE (Grupo I), 72 con riesgo de PE (Grupo II), y 24 de grupo control (Grupo III). Se utilizó una técnica automatizada de electroquimioluminiscencia (Roche). Valores <38 se consideraron sin riesgo de PE, entre 38 y 85 (< semana 34) o 38 y 110 (> semana 34) con riesgo moderado o alto riesgo dentro de las 4 semanas posteriores a la realización de dichos marcadores y >85 en embarazadas con síntomas de aparición temprana o >110 en embarazadas con síntomas de aparición tardía, PE confirmada. En el Grupo I, 33 muestras dieron relación >38 y 6 fueron menores. De 72 muestras del Grupo II 69 dieron <38 y 3 >38. Todas las muestras del Grupo III dieron relación <38. La razón de verosimilitud positiva (LR+) fue de 20,31 y la razón negativa (LR-) fue de 0,16. La relación fue >38 en la mayoría de las embarazadas con diagnóstico de PE. La determinación es útil en aquellas mujeres embarazadas que son de alto riesgo, ya sea porque tienen hipertensión o proteinuria o algún antecedente previo, en las cuales puede ser fundamental para decidir el correcto diagnóstico.


The objective of this work was to evaluate the clinical usefulness of the relation placental growth factor/soluble tyrosine-kinase type 1 receptor (sFlt-1/PlGF) for the diagnosis of PE (preeclampsia) in pregnant women at high risk and with clinical diagnosis of PE in a health center of Córdoba, Argentina. A total of 135 samples of pregnant women were processed: 39 with clinical diagnosis of PE (Group I), 72 with risk of PE (Group II), and 24 of control group (Group III). An automated electrochemiluminescence technique (Roche) was used. Ratio sFlt-1/PlGF <38 was considered without risk of PE. Between 38 and 85 (< week 34) or 38 and 110 (> week 34), with moderate risk or high risk within 4 weeks after performing these markers. To confirm diagnosis, relationships >85 in pregnant women were considered with symptoms of early onset and >110 in pregnant women with symptoms of late onset. In Group I, 33 samples reported >38 and 6 were lower. Of 72 samples from Group II, 69 gave <38 and 3, >38. All samples from Group III gave a ratio <38. The positive likelihood ratio (LR+) was 20.31 and the negative likelihood ratio (LR-), 0.16. The ratio was >38 in the majority of women already diagnosed as PE. The test is useful in those pregnant women who are at high risk of PE, either because they have hypertension or proteinuria or a previous history. In those cases it can be fundamental to decide the correct diagnosis.


O objetivo do estudo é avaliar a utilidade clínica da relação fator de crescimento placentário/receptor de tirosina-quinase tipo 1 solúvel (sFlt-1/PIGF) para o diagnóstico de pré-eclâmpsia (PE) em grávidas de alto risco e com diagnóstico clínico de PE em um centro de saúde de Córdoba, Argentina. Foram processadas 135 amostras de gestantes, sendo 39 com diagnóstico clínico de PE (Grupo I), 72 com risco de PE (Grupo II) e 24 de grupo controle (Grupo III). Foi utilizada uma técnica automatizada de eletroquimioluminescência (Roche). Valores <38 foram considerados sem risco de PE, entre 38 e 85 (

Assuntos
Humanos , Feminino , Gravidez , Pré-Eclâmpsia , Tirosina , Fator de Crescimento Placentário , Hipertensão , Sinais e Sintomas , Centros de Saúde , Risco , Grupos Controle , Gestantes , Diagnóstico , Crescimento
6.
Int. j. morphol ; 37(4): 1463-1468, Dec. 2019. graf
Artigo em Inglês | LILACS | ID: biblio-1040154

RESUMO

Acute effect of purified mimosine (MiMo) extracted from Leucaena leucocephala on testicular histopathology has been documented with seminal vesicle (SV) atrophy. Since protein phosphorylation and seminal secretions play important roles in sperm physiology, this study aimed to study the alteration of substances including tyrosine phosphorylated (TyrPho) proteins in seminal vesicle treated with MiMo. Male mice were divided into a control and experimental groups treated with purified MiMo at 3 doses of 15, 30, and 60 mg/KgBW, respectively for 35 consecutive days. The morphology and weights of SV were compared among groups. The levels of magnesium and fructosamine in SV fluid were assayed. The profiles of equally SV total proteins were compared using SDS-PAGE. The expression of seminal TyrPho proteins was detected by western blotting. Recent results showed the decreased weights of SV in MiMo treated mice compared to control. However MiMo in all doses did not affect the levels of magnesium and fructosamine in SV fluid. The SV protein expression of 130 and 55 kDas was obviously decreased in a high dose MiMo. In dose-dependent response, the expressions of 72 and 55 kDas TyrPho proteins of SV were increased. In conclusion, MiMo could affect SV morphological size and protein secretions especially TyrPho proteins.


El efecto agudo de la mimosina purificada (MiMo) extraída de Leucaena leucocephala en la histopatología testicular se ha documentado con atrofia de vesícula seminal (VS). Debido a que la fosforilación de proteínas y las secreciones seminales tienen un papel importante en la fisiología de los espermatozoides, este estudio tuvo como objetivo estudiar la alteración de sustancias como la proteína tirosina fosforilada (TyrPho) en vesículas seminales tratadas con MiMo. Los ratones se dividieron en un grupo control y un grupo experimental y se trataron con MiMo purificado en 3 dosis de 15, 30 y 60 mg / KgBW, respectivamente, durante 35 días seguidos. La morfología y los pesos de VS se compararon entre los grupos. Fueron analizados los niveles de magnesio y fructosamina en el fluido VS. Los perfiles de las proteínas totales de VS se compararon utilizando SDS-PAGE. La expresión de la proteína TyrPho en las vesículas seminales se detectó mediante transferencia de Western blot. Los resultados recientes muestran la disminución del peso de las VS en ratones tratados con MiMo, en comparación con el grupo control. Sin embargo, en ninguna de las dosis se vieron afectados por mimosina purificada los niveles de magnesio y fructosamina en el líquido de las VS. La expresión de la proteína en VS de 130 y 55 kDas disminuyó notablemente en una dosis alta de MiMo. En la respuesta dependiente de la dosis, aumentaron las expresiones de 72 y 55 kDas de las proteínas TyrPho en las VS. En conclusión, la mimosina purificada podría afectar el tamaño morfológico de las VS y la expresión de proteínas, especialmente las proteínas TyrPho.


Assuntos
Animais , Masculino , Camundongos , Fosfoproteínas/efeitos dos fármacos , Glândulas Seminais/efeitos dos fármacos , Mimosina/administração & dosagem , Tamanho do Órgão , Fosfoproteínas/metabolismo , Fosforilação , Glândulas Seminais/patologia , Tirosina/análogos & derivados , Western Blotting , Fosfotirosina , Eletroforese em Gel de Poliacrilamida , Camundongos Endogâmicos ICR , Mimosina/farmacologia
7.
Medicina (B.Aires) ; 79(supl.3): 2-5, set. 2019. tab
Artigo em Espanhol | LILACS | ID: biblio-1040540

RESUMO

La fenilcetonuria, también conocida como PKU, es el error congénito más frecuente del metabolismo de los aminoácidos. La forma grave o PKU clásica no tratada, causa una discapacidad intelectual, aunque los programas de detección en el período neonatal, el diagnóstico y el tratamiento evitan la aparición de los síntomas. A pesar de un diagnóstico y tratamiento temprano hemos observado cierta neurotoxicidad en los pacientes con PKU tratados. Analizamos los demás factores implicados, aparte de la toxicidad por las elevadas concentraciones cerebrales de fenilalanina (Phe), se revisan los defectos de síntesis de neurotransmisores, las alteración de la mielinización cerebral, el efecto de la elevación de Phe en los procesos de transporte y distribución de los aminoácidos neutros con una síntesis anómala de proteínas cerebrales, la deficiencia plasmática y cerebral de tirosina, la neurotoxicidad de los metabolitos de Phe, el defecto de la biosíntesis del colesterol o el aumento del estrés oxidativo. Las alteraciones de la sustancia blanca en los pacientes con PKU tienen un papel importante en las manifestaciones neurológicas. El tratamiento de la PKU es para toda la vida y se basa en la reducción del aporte de alimentos que contienen Phe combinado con la administración de una fórmula especial, o en el tratamiento con tetrahidrobiopterina (BH4). Se analizan nuevas opciones terapéuticas.


Phenylketonuria, also known as PKU, is the most frequent congenital inborn error of metabolism. The severe form or classic PKU untreated causes intellectual disability, although with the early detection programs in the neonatal period, diagnosis and treatment prevent the appearance of the symptoms. Despite early diagnosis and treatment we have observed some neurotoxicity in treated PKU patients. We analyzed the factors involved apart from the toxicity due to the high cerebral concentrations of phenylalanine (Phe), the defects of synthesis of neurotransmitters, the alteration of cerebral myelination, the effect of the elevation of Phe in the processes of transport and distribution of neutral amino acids with an abnormal synthesis of brain proteins, plasma and cerebral tyrosine deficiency, the neurotoxicity of Phe metabolites, the defect of cholesterol biosynthesis or the increase of oxidative stress. White matter alterations in early treated PKU patients have an important role in neurological manifestations. The treatment of PKU is for life and is based on the reduction of foods containing Phe combined with the administration of a special formula or tetrahydrobiopterin (BH4) treatment. New therapeutic options will be analyzed.


Assuntos
Humanos , Fenilalanina/efeitos adversos , Fenilcetonúrias/diagnóstico , Fenilcetonúrias/terapia , Tirosina/metabolismo , Neurônios/patologia , Fenilcetonúrias/fisiopatologia , Biopterina/análogos & derivados , Diagnóstico Precoce , Dietoterapia
8.
Arch. argent. pediatr ; 117(4): 382-386, ago. 2019. ilus
Artigo em Inglês, Espanhol | LILACS, BINACIS | ID: biblio-1054941

RESUMO

La miopatía nemalínica es un trastorno heterogéneo definido por la presencia de estructuras con forma de bastones, conocidas como cuerpos nemalínicos (o bastones de nemalina). El diagnóstico se funda en la debilidad muscular, además de la visualización de cuerpos nemalínicos en la biopsia muscular. La miopatía nemalínica no tiene cura. Las estrategias terapéuticas para este trastorno son sintomáticas y empíricas. En este artículo, presentamos el caso de una recién nacida con insuficiencia respiratoria grave y debilidad muscular generalizada, a la que se le diagnosticó miopatía nemalínica a través de la biopsia muscular. La paciente tuvo una notable disminución de la sialorrea y una mejora de los movimientos espontáneos después del tratamiento con L-tirosina. Este caso se presenta para destacar la importancia de la biopsia muscular en el diagnóstico diferencial de la hipotonía grave durante el período neonatal y el posible beneficio del aporte suplementario de L-tirosina para disminuir la sialorrea y restaurar la fuerza muscular.


Nemaline myopathy (NM) is a heterogeneous disorder defined by the presence of rod-shaped structures known as nemaline bodies or rods. The diagnosis is based on muscle weakness, combined with visualization of nemaline bodies on muscle biopsy. There is no curative treatment for nemaline myopathy. Therapeutic strategies for this condition are symptomatic and empirical. Herein, we present a newborn with severe respiratory failure and generalized muscle weakness, who was diagnosed as NM by muscle biopsy. The patient experienced remarkable decrease in sialorrhea and improvement of spontaneous movements after L-tyrosine treatment. This case is presented to emphasize the importance of muscle biopsy in the differential diagnosis of severe hypotonia during neonatal period and a possible benefit of L-tyrosine supplementation for decreasing sialorrhea and restoring muscle strength.


Assuntos
Humanos , Feminino , Recém-Nascido , Tirosina/uso terapêutico , Miopatias da Nemalina/diagnóstico , Biópsia , Miopatias da Nemalina/terapia , Evolução Fatal , Hipotonia Muscular
9.
Rev. venez. oncol ; 31(1): 2-7, mar. 2019. tab, graf
Artigo em Espanhol | LILACS, LIVECS | ID: biblio-1023588

RESUMO

OBJETIVO: Este estudio pretende evaluar la sobrevida global en los pacientes con carcinoma diferenciado de tiroides localmente avanzado yodo refractario. MÉTODO: Son 8 casos tratados con inhibidores de tirosina quinasa (Sorafenib) en el período comprendido entre 2014-2017. Las variables estudiadas fueron: Epidemiológicas, laboratorios tiroideos, histología, tratamiento, supervivencia posterior al tratamiento. Se tomó como significativo una P<0,05. RESULTADOS: Edad media entre los pacientes fue 51 años ± 22,1 años, el sexo prevaleciente fue femenino (75 %). El lugar de procedencia más incidente fue Estado Miranda (50 %). Los valores de laboratorio al momento del diagnóstico fueron tiroglobulina (290,2 ± 250,7), la TSH (11,3 ± 13,9) y la antitiroglobulina solo fue positiva en un paciente (87,5 %). La T predominante fue T3 (50 %), la N que prevaleció fue N1B (62 %) y M1 (62,5 %). El estadio predominante fue IVC (50 %). El grupo histológico predominante fue papilar (62,5 %). Se les realizó tiroidectomía total con vaciamiento bilateral al 75 % de los pacientes. Posteriormente recibieron 131I, para los cuales se obtuvieron una dosis media de 227,5 mCi con desviación de estándar: 188,1 mCi. La mayoría recibió radioterapia externa a región cervical (87,50 %). La sobrevida global 3 años posteriores al tratamiento fue 87,5 %. CONCLUSIONES. El control de la enfermedad a largo plazo en estos pacientes avanzados puede obtenerse con Sorafenib. En nuestro estudio evidenciamos que es un fármaco adecuado para controlar la enfermedad en pacientes con cáncer de tiroides yodo refractarios.(AU)


OBJECTIVE: This study aimed evaluates overall survival in patients with locally advanced thyroid iodine refractory differentiated carcinoma. METHOD: 8 cases treated with inhibitors of tyrosine kinase (Sorafenib) in the period 2014-2017. The variables studied were: epidemiological, laboratory thyroid histology, treatment, post-treatment survival. P was taken as meaningful < 0.05. RESULTS: Mean age among patients was 51 years ± 22.1 year, prevailing sex female (75 %). Place of origin more incident was Miranda State (50 %). At the time of the diagnostic laboratory values were thyroglobulin (290.2 ± 250.7), TSH (3 ± 13.9 11) and the single antithyroglobulin was positive in one patient (87.5 %). The predominant T was T3 (50 %), the N that prevailed was N1B (62 %) and M1 (62.5 %). The predominant stadium was IVC (50 %). The predominant histological group was papillary (62.5 %). The predominant stadium was IVC (50 %). The predominant histological group was papillary (62.5 %). He was performed in total thyroidectomy with bilateral clearing to 75 % of patients. Subsequently received 131I, for which an average dose of 227.5 mCi with standard deviation were obtained: 188.1 mCi. Most received radiotherapy external cervical region (87.50 %). Global survival 3 years after treatment was 87.5 %. CONCLUSIONS: The control of disease in long run in these advanced patients can get with Sorafenib. In our study we showed that it is a suitable drug to control the disease in patients with cancer of thyroid iodine refractory. (AU)


Assuntos
Humanos , Feminino , Adulto , Tireoidectomia , Tirosina/administração & dosagem , Neoplasias da Glândula Tireoide/fisiopatologia , Inibidores de Proteínas Quinases , Metástase Neoplásica , Epidemiologia , Compostos Radiofarmacêuticos , Tratamento Farmacológico
10.
Int. j. morphol ; 37(1): 65-70, 2019. graf
Artigo em Inglês | LILACS | ID: biblio-990006

RESUMO

SUMMARY: Valproic acid (VPA), an antiepileptic drug, has been demonstrated to damage histology and to change tyrosine phosphorylation patterns with increased oxidative stress in perirenal tissues. This study aimed to investigate the effect of VPA on microstructure, tyrosine phosphorylation, and lipid peroxidation of rat kidney. Adult male rats were divided into control and VPA-treated groups intraperitoneally injected with normal saline and VPA 500 mg/kgBW for 10 consecutive days, respectively (n = 7 each). The blood serum was examined for biochemical levels. The kidney tissues were routinely processed for histological observation. Total proteins from kidney were extracted to assay the malondialdehyde (MDA) levels and phosphorylation expression. The results showed that VPA significantly decreased blood glucose levels while tend to increase urea nitrogen and creatinine. MDA levels in VPA group were significantly higher that of control. Renal cortex of VPA-treated animals revealed vasodilatations. Although the ratio of a renal phosphorylated 72 kDa protein/ beta actin expression seemed to be not different in both groups, VPA significantly decreased the intensity of beta actin. In conclusion, VPA dilates renal microvasculature with increasing of MDA but suppresses the actin expression.


RESUMEN: Se ha demostrado que el ácido valproico (AVP), un fármaco antiepiléptico, daña la histología y cambia los patrones de fosforilación de la tirosina con el aumento del estrés oxidativo en los tejidos perirrenales. Este estudio tuvo como objetivo investigar el efecto del AVP en la microestructura, la fosforilación de la tirosina y la peroxidación lipídica del riñón de rata. Se dividieron ratas macho adultas en grupos control y tratados con AVP. Durante 10 días consecutivos fueron inyectadas por vía intraperitoneal con solución salina normal y 500 mg / kg de PC respectivamente (n = 7 cada uno). Se analizó el suero sanguíneo para determinar los niveles bioquímicos. Los tejidos renales se procesaron de forma rutinaria para la observación histológica. Las proteínas totales del riñón se extrajeron para analizar los niveles de malondialdehído (MDA) y la expresión de la fosforilación. Los resultados mostraron que el AVP disminuyó significativamente los niveles de glucosa en la sangre, mientras que tienden a aumentar el nitrógeno ureico y la creatinina. Los niveles de MDA en el grupo de AVP fueron significativamente más altos que los del control. La corteza renal de los animales tratados con AVP reveló vasodilataciones. Aunque la proporción de una expresión de proteína / actina de 72 kDa fosforilada renal no parece ser diferente en ambos grupos, el AVP disminuyó significativamente la intensidad de la actina beta. En conclusión, el AVP dilata la microvasculatura renal al aumentar el MDA, pero suprime la expresión de actina.


Assuntos
Animais , Masculino , Ratos , Tirosina/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos dos fármacos , Ácido Valproico/farmacologia , Rim/efeitos dos fármacos , Anticonvulsivantes/farmacologia , Tamanho do Órgão , Fosforilação , Vasodilatação/efeitos dos fármacos , Western Blotting , Ratos Wistar , Eletroforese em Gel de Poliacrilamida , Malondialdeído
11.
Int. j. morphol ; 36(3): 835-840, Sept. 2018. graf
Artigo em Inglês | LILACS | ID: biblio-954194

RESUMO

Tyrosine phosphorylated proteins have been localized and identified in male reproductive tissues such as testis and capacitated/ acrosome reacted sperm except epididymis. The changes of such proteins are associated with decreased sperm quality of valproic acid treatment. This study aimed to investigate the presence and alterations of protein phosphorylation in epididymal epithelium and fluid of rats treated VPA. Sixteen adult male rats were divided into control and VPA-treated groups (n=8/ each). Treated rats were injected with VPA (500 mg/ kgBW, intraperitoneally) for 10 consecutive days. At the end of experiment, the monoclonal antiphosphotyrosine (clone 4G10) was used for immunohistochemistry to probe tyrosine phosphorylated proteins and also to examine the expression of such proteins using immuno-Western blotting in epididymal tissue and fluid. The result showed that positive reactivity of phosphorylated proteins was clearly observed in cytoplasmic principle cells, nuclei of apical & basal cells and sperm mass surrounded with epididymal fluids. The profiles of phosphorylated proteins in epididymal fluid were 182, 127, 80, 70, 57, 45, 34, and 31 kDas, respectively. Interestingly, VPA affected the changes of phosphorylated proteins and β actin in head, body, and tail epididymal fluids. We conclude that tyrosine phosphorylated proteins were detected in epididymal epithelium and fluid. The expressions of those proteins and actin were altered under VPA treating.


Las proteínas tirosina fosforiladas han sido localizadas e identificadas en tejidos reproductores masculinos tales como testículos y espermatozoides, capacitados a nivel acrosómico, excepto en el epidídimo. Los cambios de estas proteínas están asociadas con una disminución de la calidad del esperma en el tratamiento con ácido valproico (AVP). Este estudio tuvo como objetivo investigar la presencia y las alteraciones de la fosforilación de proteínas en el epitelio epididimal y en el fluido espermático de ratas tratadas con AVP. Dieciséis ratas macho adultas se dividieron en dos grupos: control y tratadas con AVP (n = 8 / cada uno). A las ratas tratadas se les inyectó AVP por vía intraperitoneal (500 mg / kg de peso corporal) durante 10 días consecutivos. Al final del experimento, se realizó inmunohistoquímica con la anti-fosfotirosina monoclonal (clon 4G10) para sondear las proteínas tirosina fosforiladas y también para examinar la expresión de tales proteínas usando inmunotransferencia Western, en tejido y fluido epididimarios. El resultado mostró reactividad positiva de proteínas fosforiladas en células citoplásmicas principales, en los núcleos de las células apicales y basales y en la masa de esperma rodeada por fluidos epididimarios. Los perfiles de proteínas fosforiladas en el fluido epididimal fueron 182, 127, 80, 70, 57, 45, 34 y 31 kDas, respectivamente. El AVP provocó cambios en las proteínas fosforiladas y en la β actina de los fluidos epididimarios de cabeza, cuerpo y cola del epidídimo. Concluimos que las proteínas tirosina fosforiladas se detectaron en el epitelio y el fluido epididimarios. Las expresiones de esas proteínas y de la β actina se alteraron bajo tratamiento con AVP.


Assuntos
Animais , Masculino , Ratos , Fosfoproteínas/efeitos dos fármacos , Tirosina/efeitos dos fármacos , Ácido Valproico/administração & dosagem , Actinas/efeitos dos fármacos , Anticonvulsivantes/administração & dosagem , Fosfoproteínas/metabolismo , Fosforilação , Tirosina/metabolismo , Imuno-Histoquímica , Western Blotting , Actinas/metabolismo , Ratos Sprague-Dawley , Fosfotirosina , Epididimo
12.
Arq. gastroenterol ; 55(2): 164-169, Apr.-June 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-950504

RESUMO

ABSTRACT BACKGROUND: Ostomy is a surgical procedure that creates a stoma that aims to construct a new path for the output of feces or urine. The relationship of oxidative stress (OxS) markers in patients with ostomy is still poorly described. OBJECTIVE: The present study was aimed at investigating the changes in oxidative stress parameters in peripheral blood collected from ostomy patients when compared with a healthy control group. METHODS: It was evaluated 29 ostomy patients and 30 healthy control patients. The oxidative stress parameters evaluated were: lipid peroxidation [lipid hydroperoxide (LPO), 8-isoprostane (8-ISO) and 4-hydroxynonenal (4-HNE)], protein oxidation and nitration [carbonyl and 3-nitrotyrosine (3-NT)] and DNA oxidation [8-hydroxy-2'-deoxyguanosine (8-OHDG)] in serum from ostomy patients compared to health controls. RESULTS: The data showed an increase of LPO, 8-ISO, 4-HNE, 3-NT and 8-OHDG in serum collected from ostomy patients when compared to healthy controls. CONCLUSION: The findings support the hypothesis that ostomy triggers the oxidative stress observed in the blood collected from these patients.


RESUMO CONTEXTO: Ostomia é um procedimento cirúrgico que cria um estoma com objetivo de construir um novo caminho para a saída das fezes ou urina. A relação dos marcadores de estresse oxidativo em pacientes ostomizados ainda é pouco descrita. OBJETIVO: O presente estudo tem como objetivo investigar as alterações dos parâmetros de estresse oxidativo em sangue de pacientes ostomizados comparados a controles saudáveis. MÉTODOS: Foram avaliados 29 pacientes ostomizados e 30 controles saudáveis. Os parâmetros de estresse oxidativo avaliados foram: peroxidação lipídica [hidroperóxido de lipídio (LPO), 8-isoprostano (8-ISO) e 4-hidroxinonenal (4-HNE)], oxidação e nitração de proteínas [carbonila e 3-nitrotirosina (3-NT)] e oxidação do DNA [8-hidroxi-2'-desoxiguanosina (8-OHDG)] em soro de pacientes ostomizados comparados a controles saudáveis. RESULTADOS: Os dados mostraram um aumento de LPO, 8-ISO, 4-HNE, 3-NT e 8-OHDG em soro de pacientes ostomizados em comparação a controles saudáveis. CONCLUSÃO: Os achados sustentam a hipótese de que a ostomia desencadeia o estresse oxidativo observado no sangue coletado destes pacientes.


Assuntos
Humanos , Masculino , Feminino , Adulto , Idoso , Estomia/efeitos adversos , Peroxidação de Lipídeos , Estresse Oxidativo/efeitos dos fármacos , Estomas Cirúrgicos/efeitos adversos , Tirosina/efeitos adversos , Tirosina/sangue , Dano ao DNA , Ensaio de Imunoadsorção Enzimática , Biomarcadores/sangue , Dinoprosta/análogos & derivados , Dinoprosta/sangue , Estudos de Casos e Controles , Aldeídos/sangue , Peróxidos Lipídicos/sangue , Pessoa de Meia-Idade
13.
Int. j. morphol ; 35(4): 1322-1327, Dec. 2017. graf
Artigo em Inglês | LILACS | ID: biblio-893135

RESUMO

SUMMARY: Spermatogenesis is a major process in testis occurring from puberty through life span of males. The tyrosine phosphorylation is assumed to play roles in spermatogenesis because this process is important for cell proliferations, divisions, and differentiations. However, the localizations and identifications of phosphorylated proteins in testicular tissue of adult male rats are still unclear. Therefore, this study attempted to immuno-localize and identify such proteins in testicular tissues of Sprague-Dawley rats. The monoclonal anti-phosphotyrosine (clone 4G10) was used to probe tyrosine phosphorylated proteins and also to examine the expression of such proteins using immuno-Western blotting in rat testis. The result showed that positive reactivity of tyrosine phosphorylated proteins was clearly observed in interstitial endocrine cells (Leydig cells), sustentocytes (Sertoli cells), spermatogonia, spermatocytes, and spermatids (round and elongated), respectively. The expressions of testicular tyrosine phosphorylated proteins were 200, 131, 93, 70, 60, and 48 kDas, respectively. In conclusion, testicular tyrosine phosphorylated proteins were localized in both germinal epithelium and interstitial endocrine cells of adult Sprague-Dawley rats.


RESUMEN: La espermatogénesis es un proceso importante en los testículos que ocurre desde la pubertad a lo largo de la vida de los machos. Se supone que la fosforilación de la tirosina desempeña papeles en la espermatogénesis, debido a que este proceso es importante para las proliferaciones, divisiones y diferenciaciones celulares. Sin embargo, las localizaciones e identificaciones de proteínas fosforiladas en el tejido testicular de ratas macho adultas todavía no están claras. Por lo tanto, este estudio intentó inmuno-localizar e identificar dichas proteínas en tejidos testiculares de ratas Sprague-Dawley. La anti-fosfotirosina monoclonal (clon 4G10) se usó para sondar proteínas tirosina fosforiladas y también para examinar la expresión de tales proteínas usando inmunotransferencia Western en testículo de rata. El resultado mostró que la actividad positiva de las proteínas tirosina fosforiladas se observó claramente en endocrinocitos intersticiales (células de Leydig), sustentocitos (células de Sertoli), espermatogonias, espermatocitos y espermátidas (redondas y alargadas), respectivamente. Las expresiones de las proteínas tirosina fosforiladas testiculares fueron de 200, 131, 93, 70, 60 y 48 kDas, respectivamente. En conclusión, las proteínas tirosina fosforiladas fueron localizadas en ambos epitelios germinales y endocrinocitos intersticiales de ratas adultas Sprague-Dawley.


Assuntos
Animais , Masculino , Ratos , Fosfoproteínas/análise , Fosfoproteínas/metabolismo , Testículo/química , Tirosina/análise , Tirosina/metabolismo , Imuno-Histoquímica , Western Blotting , Ratos Sprague-Dawley
14.
Electron. j. biotechnol ; 29: 1-6, sept. 2017. graf, tab
Artigo em Inglês | LILACS | ID: biblio-1016090

RESUMO

Background: During salt stress, the yeast Debaryomyces hansenii synthesizes tyrosine as a strategy to avoid the oxidation of proteins. Tyrosine reacts with nitrogen radicals to form 3-nitrotyrosine. 3-nitrotyrosine prevents the effects of associated oxidative stress and thus contributes to the high halotolerace of the yeast. However, the mechanism of how D. hansenii counteracts the presence of this toxic compound is unclear. In this work, we evaluated D. hansenii's capacity to assimilate 3-nitrotyrosine as a unique nitrogen source and measured its denitrase activity under salt stress. To identify putative genes related to the assimilation of 3-nitrotyrosine, we performed an in silico search in the promoter regions of D. hansenii genome. Results: We identified 15 genes whose promoters had binding site sequences for transcriptional factors of sodium, nitrogen, and oxidative stress with oxidoreductase and monooxygenase GO annotations. Two of these genes, DEHA2E24178g and DEHA2C00286g, coding for putative denitrases and having GATA sequences, were evaluated by RT-PCR and showed high expression under salt and nitrogen stress. Conclusions: D. hansenii can grow in the presence of 3-nitrotyrosine as the only nitrogen source and has a high specific denitrase activity to degrade 3-nitrotyrosine in 1 and 2 M NaCl stress conditions. The results suggest that given the lack of information on transcriptional factors in D. hansenii, the genes identified in our in silico analysis may help explain 3-nitrotyrosine assimilation mechanisms.


Assuntos
Tirosina/análogos & derivados , Tirosina/metabolismo , Debaryomyces/genética , Debaryomyces/metabolismo , Tirosina/genética , Transcrição Gênica , Leveduras , Sequências Reguladoras de Ácido Nucleico , Regiões Promotoras Genéticas , Estresse Oxidativo , Reação em Cadeia da Polimerase em Tempo Real , Osmorregulação , Extremófilos , Estresse Salino , Nitrogênio/metabolismo
15.
Rev. Soc. Bras. Med. Trop ; 50(4): 489-498, July-Aug. 2017. graf
Artigo em Inglês | LILACS | ID: biblio-896995

RESUMO

Abstract INTRODUCTION Renal damage is a consequence of severe malaria, and is generally caused by sequestration of Plasmodium falciparum -infected erythrocytes in the renal microcirculation, which leads to obstruction, hypoxia, and ischemia. This triggers high mobility group box 1 (HMGB1) to send a danger signal through toll-like receptors 2 and 4. This signal up-regulates inducible nitric oxide (iNOS) and nitrotyrosine to re-perfuse the tissue, and also increases heat shock protein 70 (HSP70) expression. As no study has examined the involvement of intracellular secondary molecules in this setting, the present study compared the renal expressions of HSP70, HMGB1, iNOS, and nitrotyrosine between mice suffered from severe malaria and normal mice. METHODS C57BL/6 mice were divided into an infected group (intraperitoneal injection of 10 6 P. berghei ANKA) and a non-infected group. Renal damage was evaluated using hematoxylin eosin staining, and immunohistochemistry was used to evaluate the expressions of HSP70, HMGB1, iNOS, and nitrotyrosine. RESULTS Significant inter-group differences were observed in the renal expressions of HSP70, HMGB1, and iNOS (p=0.000, Mann-Whitney test), as well as nitrotyrosine (p=0.000, independent t test). The expressions of HSP70 and HMGB1 were strongly correlated (p=0.000, R=1.000). No correlations were observed between iNOS and HMGB, HMGB1 and nitrotyrosine, HSP70 and nitrotyrosine, or iNOS and nitrotyrosine. CONCLUSIONS It appears that HMGB1, HSP70, iNOS, and nitrotyrosine play roles in the renal damage that is observed in mice with severe malaria. Only HSP70 expression is strongly correlated with the expression of HMGB1.


Assuntos
Animais , Feminino , Tirosina/antagonistas & inibidores , Proteínas de Choque Térmico HSP70/metabolismo , Proteína HMGB1/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Injúria Renal Aguda/parasitologia , Malária/complicações , Malária/metabolismo , Tirosina/metabolismo , Índice de Gravidade de Doença , Modelos Animais de Doenças , Camundongos , Camundongos Endogâmicos C57BL
16.
Int. j. morphol ; 35(2): 667-675, June 2017. ilus
Artigo em Inglês | LILACS | ID: biblio-893038

RESUMO

The aim of present study was to investigate the effect of Momordica cochinchinensis (Gag) aril (GA) aqueous extract on male reproductive system of streptozotocin (STZ)-induced hyperglycemia (HG) mice. GA were extracted with distilled water (DW) and analyzed for in vitro antioxidant capacities. ICR male mice were divided into 7 groups: 1) control, 2) DW, 3) GA 1000 mg/kg BW, 4) HG, 5) HG + glibenclamide, 6 and 7) HG + GA 500 and 1000 mg/kg BW respectively (7 mice/ group). In HG groups, mice were induced by STZ at single dose (150 mg/kg BW). They were treated for consecutive 35 days. All groups were compared for blood glucose levels, weights and histopathologies of reproductive organs, sperm concentration including testicular tyrosine phosphorylation protein patterns by Immuno-Western blotting. The results showed that GA processed antioxidant activities and could significantly decrease blood glucose levels and increase sperm concentration in HG mice. Moreover, GA could change the density of a testicular 70 kDa protein in HG-GA groups. In conclusion, GA extract could improve hyperglycemia and male reproductive damages in STZ-induced HG mice.


El objetivo de este estudio fue investigar el efecto del extracto acuoso de Momordica cochinchinensis (Gag) aril (GA) en el sistema reproductor masculino de ratones hiperglucémicos inducidos por estreptozotocina (STZ). GA fue extraída con agua destilada (DW) y se analizaron las capacidades antioxidantes in vitro. Ratones ICR machos fueron divididos en 7 grupos: 1) control, 2) DW, 3) GA 1000 mg / kg PC, 4) HG, 5) HG + glibenclamida, 6 y 7) HG + GA 500 y 1000 mg / kg PC, respectivamente (7 ratones / grupo). En los grupos HG, los ratones fueron inducidos con STZ en dosis única (150 mg / kg BW). Fueron tratados durante 35 días consecutivos. En todos los grupos se compararon los niveles de glucosa en sangre, los pesos y las histopatologías de los órganos reproductores, la concentración de espermatozoides, incluídos los patrones testiculares de proteínas tirosina fosforilada por Inmuno-Western blot. Los resultados mostraron que GA procesaba actividades antioxidantes y podían disminuir significativamente los niveles de glucosa en sangre y aumentar la concentración de espermatozoides en ratones HG. Además, GA podría cambiar la densidad de una proteína testicular de 70 kDa en grupos HG-GA. En conclusión, el extracto de GA podría mejorar la hiperglucemia y los daños reproductivos masculinos inducidos por STZ en ratones HG.


Assuntos
Animais , Masculino , Camundongos , Doenças Testiculares/tratamento farmacológico , Extratos Vegetais/administração & dosagem , Momordica/química , Hiperglicemia/tratamento farmacológico , Hipoglicemiantes/administração & dosagem , Antioxidantes/administração & dosagem , Fenóis/análise , Fosforilação/efeitos dos fármacos , Contagem de Espermatozoides , Espermatozoides/efeitos dos fármacos , Testículo/efeitos dos fármacos , Tirosina , Flavonoides/análise , Western Blotting , Diabetes Mellitus Experimental , Camundongos Endogâmicos ICR , Antioxidantes/química
17.
Prensa méd. argent ; 103(6): 331-345, 20170000.
Artigo em Espanhol | LILACS, BINACIS | ID: biblio-1377937

RESUMO

La Resistencia Concomitante Antitumoral (RC) es el fenómeno según el cual un individuo portador de un tumor inhibe o retarda el crecimiento de implantes tumorales secundarios. Este fenómeno ha sido descripto en animales y en seres humanos y puede ser inducido tanto por tumores inmunogénicos como no-inmunogénicos. El estudio de la RC puede darnos indicios sobre mecanismos de control de las metástasis desde que las metástasis son, de hecho, implantes secundarios naturales desarrollados espontáneamente durante el crecimiento de un tumor primario. En este sentido la experiencia clínica y numerosos datos experimentales han revelado que la extirpación quirúrgica de un tumor puede ser seguida por una abrupta aceleración del crecimiento metastásico sugiriendo que, bajo ciertas circunstancias, un tumor puede ejercer un control inhibitorio sobre sus propias metástasis. En nuestro laboratorio hemos estudiado la RC asociada al crecimiento de numerosos tumores de ratón de diferente origen, tipo histológico e inmunogenicidad. Nuestros resultados demostraron que durante el crecimiento de un tumor primario se generan dos eventos temporalmente separados de RC. El primer evento es producido sólo por tumores inmunogénicos de pequeño tamaño (<500 mm3 ), es específico de tumor y es producido por mecanismos inmunológicos dependientes del timo. Por otro lado, el segundo evento de RC es inducido tanto por tumores inmunogénicos como no-inmunogénicos de gran tamaño (≥ 2000 mm3 ), no es específico de tumor, es timo independiente y correlaciona con la presencia de un factor sérico de bajo peso molecular que demostró tener capacidad para inhibir la proliferación de células tumorales tanto in vitro como in vivo. Cuando esta actividad antitumoral no estaba presente en el suero ­en nuestros modelos, los dos únicos casos estuvieron asociados a tumores altamente metastásicos­ el segundo evento de RC no se producía. Estos resultados sugieren una correlación directa entre la actividad sérica antitumoral, el segundo evento de RC y la capacidad para restringir el crecimiento metastásico.Aunque el primer evento de RC es producido, como dijimos arriba, por una respuesta inmunológica convencional mediada por células T, la naturaleza química del factor sérico asociado a la más universal manifestación de la RC (esto es, el segundo evento de RC), permaneció siendo un enigma por muchos años. En un trabajo reciente, identificamos ese factor sérico antitumoral como una mezcla de metatirosina y orto-tirosina, dos isómeros de tirosina que no están presentes en proteínas normales. Ambos isómeros fueron capaces de inhibir el crecimiento de diferentes tumores murinos que generan RC y restringieron el crecimiento de metástasis establecidas producidas por tumores que no generan RC pero son sensibles a la RC generada por otros tumores. A su vez, y tan significativo como lo anterior, estos efectos antitumorales se lograron sin ningún efecto colateral indeseado Una comprensión más profunda de los mecanismos moleculares asociados con el efecto antitumoral de estos isómeros de tirosina podría, eventualmente, ayudar a desarrollar métodos nuevos y menos tóxicos para combatir las enfermedades malignas; en particular para limitar el crecimiento acelerado de las metástasis después de la extirpación quirúrgica del tumor primario o después del padecimiento de traumas o estresores que pudieran ­despertar­ metástasis de su estado de ­tumor dormido­.


Concomitant tumor resistance (CR) is a phenomenon in which a tumor-bearing host is resistant to the growth of secondary tumor implants. This phenomenon has been described in human and animal systems and it can be generated by both immunogenic and non-immunogenic tumors. The relevance of CR to the mechanisms of metastases control has been highlighted by numerous observations showing that the removal of human and murine tumors may be followed by an abrupt increase in metastatic growth, suggesting that, upon certain circumstances, a primary tumor exerts a controlling action on its metastases which could be considered as secondary tumor implants developed spontaneously during the primary tumor growth. In our laboratory we have studied the CR induced by many murine tumors widely different in origin, histologic type and immunogenicity. Our results support the idea that during the primary tumor growth, there exist two temporally separate events of CR: the first one was exhibited only by small (<500 mm3 ) immunogenic tumors, it was tumor-specific and mediated by classical T-dependent immunological mechanisms. The second event was induced by both im munogenic and nonimmunogenic large (≥ 2000 mm3 ) tumors; it was non-tumor specific, thymus independent and correlated with the presence of a serum factor of low molecular weight that inhibited the in vitro and in vivo proliferation of tumor cells. When this anti-tumor serum activity was absent ­ in our hands, the only two cases were associated with highly metastatic tumors ­ the second event of CR did not exist, suggesting a direct correlation between the anti-tumor serum activity, the second event of CR and the ability to restrain metastatic growth. Although the mechanism associated with the first event of CR has, as said above, been elucidated as T cell­dependent, the molecular nature of the antitumor serum factor(s), which is at the root of the most universal manifestation of CR (that is, the second event of CR), remained an enigma for many years. In a recently published paper, we identified that antitumor serum factor(s) as a mixture of meta-tyrosine and ortho-tyrosine, two isomers of tyrosine that are not present in normal proteins. Both meta- and ortho-tyrosine inhibited the growth of different murine models of cancer that generate CR and could also block established spontaneous metastases produced by other murine models that do not generate CR but are very sensitive to the CR induced by other tumors. In addition, and most importantly, these anti-tumor effects were achieved without any collateral damage to the organism. A more profound understanding of the molecular mechanisms associated with the anti-tumor effects mediated by meta- and ortho-tyrosine could contribute to develop new and more harmless means to manage malignant diseases, especially by limiting the development of metastases that arise after resection of primary tumors or after other stressors that may promote the escape of metastases from dormancy.


Assuntos
Humanos , Tirosina , Metástase Neoplásica/prevenção & controle , Antineoplásicos
18.
Santiago; Chile. Ministerio de Salud; 1ª Edición; 2017. 25 p. tab.
Monografia em Espanhol | BRISA/RedTESA, LILACS | ID: biblio-882711

RESUMO

INTRODUCCIÓN: La fenilcetonuria es una enfermedad congénita del metabolismo, causada en la mayoría de los casos por el déficit de la enzima hepática fenilalanina hidroxilasa, responsable de transformar la fenilalanina a tirosina, esto da como resultado concentraciones elevadas de fenilalanina y sus metabolitos, fenilacetato y fenilactato en sangre. Además la fenilalanina tendrá interferida su vía de transformación en tirosina, ya que la fenilalanina hidroxilasa no se habrá formado bien, lo que se traduce en un retardo mental. La incidencia de fenilcetonuria es de 13.500 a 19.000 nacimientos en EEUU. TECNOLOGÍAS SANITARIAS ANALIZADAS: La información sobre los efectos de la Sapropterina está basada en dos estudios. El resumen de los resultados es el siguiente. Los resultados arrojan que existe un beneficio del tratamiento de la Fenilcetonuria con Sapropterina para pacientes que responden a la misma. El tratamiento resultó eficaz en disminuir considerablemente la concentración de Fenililanina en sangre y una tolerancia mayor a la misma. A pesar de lo anterior, cabe destacar que es necesario estudios que consideren la efectividad de la Sapropterina en el largo plazo, que estudie desenlaces finales y no solo intermedios. A pesar de que existen estudios que consideran un período relativamente largo de estudio, dando indicios de buenos resultados del tratamiento con Sapropterina, se necesitan estudios que aborden la investigación con mayor control sobre la población (ensayos aleatorios controlados) para evaluar la efectividad en el largo plazo con mayor certeza. Es también importante mayor investigación que genere evidencia sobre los efectos del tratamiento según sea la severidad de la enfermedad, ya que los estudios encontrados no permiten tales aseveraciones. EFICACIA DE LOS TRATAMENTOS: La información sobre los efectos de la Sapropterina está basada en dos estudios. El resumen de los resultados es el siguiente. Los resultados arrojan que existe un beneficio del tratamiento de la Fenilcetonuria con Sapropterina para pacientes que responden a la misma. El tratamiento resultó eficaz en disminuir considerablemente la concentración de Fenililanina en sangre y una tolerancia mayor a la misma. A pesar de lo anterior, cabe destacar que es necesario estudios que consideren la efectividad de la Sapropterina en el largo plazo, que estudie desenlaces finales y no solo intermedios. A pesar de que existen estudios que consideran un período relativamente largo de estúdio , dando indicios de buenos resultados del tratamiento con Sapropterina, se necesitan estudios que aborden la investigación con mayor control sobre la población (ensayos aleatorios controlados) para evaluar la efectividad en el largo plazo con mayor certeza. Es también importante mayor investigación que genere evidencia sobre los efectos del tratamiento según sea la severidad de la enfermedad, ya que los estudios encontrados no permiten tales aseveraciones.. EVALUACIÓN ECONÓMICA: Se encontró una evaluación económica para sapropterina y dos reportes del CADTH y NHS. La evaluación económica corresponde a un análisis de costo-utilidad, realizado en Egipto, donde se compara Sapropterina versus dieta libre de fenilalanina en pacientes con diagnóstico de fenilcetonuria. Los autores concluyen que Sapropterina, en Egipto, no presenta una buena relación precio-calidad en comparación a dieta libre de fenilalanina. El impacto presupuestario supera la disponibilidad del fondo, por lo que no se continúa con la evaluación. CONCLUSIÓN: Para dar cumplimiento al artículo 28° del Reglamento que establece el proceso destinado a determinar los diagnósticos y tratamientos de alto costo con Sistema de Protección Financiera, según lo establecido en los artículos 7°y 8° de la ley N°20.850, aprobado por el decreto N°13 del Ministerio de Salud, se concluye que el presente informe de evaluación se considera no favorable, dado que su impacto presupuestario supera el 80% del fondo disponible, de acuerdo a lo establecido en el Título III. de las Evaluaciones Favorables de la Norma Técnica N° 0192 de este mismo Ministerio.


Assuntos
Humanos , Fenilcetonúrias/tratamento farmacológico , Tirosina/uso terapêutico , Avaliação da Tecnologia Biomédica/economia , Avaliação em Saúde/economia
19.
São Paulo; s.n; s.n; 2017. 337 p. graf, tab, ilus.
Tese em Português | LILACS | ID: biblio-878544

RESUMO

Tirosina, um aminoácido proteinogênico, de fundamental importância para nossa sobrevivência, foi objeto de estudo para a confecção da presente tese. Investigado frente às três reações de acoplamento cruzado mais exploradas nos últimos anos, Suzuki-Miyaura, Heck e Sonogashira, a 3-iodotirosina comportou-se como um excelente substrato na formação de unidades biarílicas, derivados estilbeno, formação de heterociclos do tipo 1,2,3-triazóis, quinolinas, benzofuranos e flavonas, bem como a formação de dipeptídeos Tyr-Tyr. A reação entre a 3-iodotirosina com diferentes nucleófilos de boro via reação de Suzuki- Miyaura, além de dar origem às unidades biarílicas, forneceu derivados do estilbeno, usados como substratos na construção de quinolinas, alcançadas por meio da reação multicomponente de Povarov, com catálise de prata em apenas 40 minutos sob irradiação de micro-ondas. Alguns desses derivados estilbeno, apresentaram ainda uma acentuada fluorescência, a qual foi medida em diferentes polaridades. Ao explorarmos a reação entre a 3-iodotirosina e acetilenos, derivados alquinílicos puderam ser convenientemente preparados, permitindo seu uso como materiais de partida na reação de cicloadição de Huisgen, no preparo de anéis triazólicos. Produtos provenientes da adição estereosseletiva de oxa-Michael, entre o anel fenólico da tirosina e aldeídos propargílicos, forneceram compostos carbonílicos α,ß-insaturados capazes de reagirem via acoplamento intramolecular de Heck, levando a derivados 2-aril-3- formil-5-alanilbenzofuranos ou ainda, apenas alterando a atmosfera inerte de nitrogênio por monóxido de carbono, a formação de 2-aril-6-alanilflavonas via acilação intramolecular redutiva. Além da metodologia de síntese explorada na tese, alguns dos compostos obtidos apresentaram atividade biológica seletiva contra células de melanoma e leucemia, bem como atividade antiparasitária frente ao Plasmodium falciparum, não afetando a proliferação de células sadias. Dessa forma, os resultados apresentados, agregam ainda mais valor sintético e biológico ao aminoácido tirosina, explorados de forma inédita


Tyrosine, a proteinogenic amino acid of fundamental importance for life, was the object of study for the research that is presented in this thesis. When 3-iodotyrosine was used in the three different types of cross-coupling reactions that have been exploited the most in recent years, namely the Suzuki-Miyaura, Heck and Sonogashira coupling reactions, 3-iodotyrosine as an excellent substrate for the formation of biaryl units, stilbene derivatives, 1,2,3-triazoletype heterocycles, quinolines, benzofurans and flavones, and Tyr-Tyr dipeptides. This work is organized into sections in order to facilitate ease of reading. The reaction between 3-iodotyrosine and different boron nucleophiles via the Suzuki- Miyaura coupling reaction, in addition to giving the biaryl units, also provided stilbene derivatives, which were used as substrates for the construction of quinolines via multicomponent Povarov reactions. The Povarov was performed with silver catalysis under 40 minutes of microwave irradiation. Some of these stilbene derivatives showed a marked fluorescence, which was measured in solvents with different polarities. By exploring the Sonogashira coupling reaction between 3-iodotyrosine and acetylenes, alkynyl derivatives could be conveniently prepared, which in turn could be used as starting materials in Huisgen cycloaddition reactions to synthesize1,2,3-triazole rings. Products from the stereoselective addition of oxa-Michael, between the phenolic ring of tyrosine and propargyl aldehydes, provided 945;,946;-unsaturated carbonyl compounds capable of reacting via Heck intramolecular coupling, leading to 2-aryl-3-formyl-5-alanylbenzofurans or by simply changing the inert atmosphere of nitrogen by carbon monoxide, the formation of 2- aryl-6-alanylflavones via reductive intramolecular acylation. In addition to the synthesis methodology explored in the thesis, some of the compounds showed selective biological activity against melanoma and leukemia cells, as well as antiparasitic activity against Plasmodium falciparum, without affecting the proliferation of healthy cells. In this way, the presented results add even more synthetic and biological value to the amino acid tyrosine, explored in an unprecedented way


Assuntos
Tirosina/análise , Fluorescência , Ensaios de Seleção de Medicamentos Antitumorais , Micro-Ondas , Neoplasias , Antimaláricos
20.
Braz. j. med. biol. res ; 50(12): e6733, 2017. graf
Artigo em Inglês | LILACS | ID: biblio-888967

RESUMO

Myostatin is a novel negative regulator of skeletal muscle mass. Myostatin expression is also found in heart in a much less extent, but it can be upregulated in pathological conditions, such as heart failure. Myostatin may be involved in inhibiting protein synthesis and/or increasing protein degradation in skeletal and cardiac muscles. Herein, we used cell cultures and isolated muscles from rats to determine protein degradation and synthesis. Muscles incubated with myostatin exhibited an increase in proteolysis with an increase of Atrogin-1, MuRF1 and LC3 genes. Extensor digitorum longus muscles and C2C12 myotubes exhibited a reduction in protein turnover. Cardiomyocytes showed an increase in proteolysis by activating autophagy and the ubiquitin proteasome system, and a decrease in protein synthesis by decreasing P70S6K. The effect of myostatin on protein metabolism is related to fiber type composition, which may be associated to the extent of atrophy mediated effect of myostatin on muscle.


Assuntos
Animais , Masculino , Fibras Musculares Esqueléticas/efeitos dos fármacos , Fibras Musculares Esqueléticas/metabolismo , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Miostatina/farmacologia , Proteínas Musculares/efeitos dos fármacos , Proteínas Musculares/metabolismo , Fosforilação/efeitos dos fármacos , Fosforilação/fisiologia , Fatores de Tempo , Tirosina/efeitos dos fármacos , Tirosina/metabolismo , Expressão Gênica , Células Cultivadas , Western Blotting , Reprodutibilidade dos Testes , Ratos Wistar , Reação em Cadeia da Polimerase em Tempo Real , Proteólise/efeitos dos fármacos
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