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1.
Int J Biol Macromol ; 262(Pt 1): 129823, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38296146

RESUMO

The crosslinking of the polymer matrix with compatible macromolecules results in a three-dimensional network structure that offers an enhancement in the controlled release properties of the material. In this sense, this work aimed to improve the release profile of mefenamic acid (MAC) through crosslinking strategies. κ-Carrageenan/sericin crosslinked blend was obtained by covalent and thermal crosslinking and the different formulations were characterized. The gastroresistant potential and release profile were evaluated in the dissolution assay. The effect and characterization of the particles were investigated. Multiple units presented high entrapment efficiency (94.11-104.25), high drug loading (36.50-47.50 %) and adequate particle size (1.34-1.57 mm) with rough surface and visually spherical shape. The Weibull model showed that drug release occurred by relaxation, erosion and Fickian diffusion. Material stability and absence of MAC -polymer interactions were demonstrated by FTIR and thermogravimetric analysis. DSC showed a stable character of MAC in the drug-loaded beads. Moreover, the application studies of κ-Car/Ser/carboxymethylcellulose in the in vitro intestine mode showed that the crosslinked blend increased cell viability (>85 %), while free MAC exhibited a cytotoxic effect. Finally, the crosslinked k-Car/Ser blend MAC -loaded showed promising properties of a sustained release form of anti-inflammatory drug.


Assuntos
Sericinas , Sericinas/química , Ácido Mefenâmico/farmacologia , Polímeros , Carragenina/química , Liberação Controlada de Fármacos , Preparações de Ação Retardada/química
2.
Artigo em Espanhol | LILACS, UY-BNMED, BNUY | ID: biblio-1358072

RESUMO

La Retinosquisis ligada al X, que se presenta fundamentalmente en varones, es una enfermedad genética caracterizada por agudeza visual reducida debido a degeneración macular. Su prevalencia es de 1/5000 varones en todo el mundo. Se manifiesta desde la primera década de la vida con pérdida de la visión que progresa hasta la adolescencia y se mantiene estable hasta la 4ta década de la vida, momento en que presenta un declive importante. El fondo de ojo suele mostrar esquisis. Las mujeres portadoras rara vez presentan síntomas. El gen involucrado es RS1, codifica para Retinosquina, proteína que participa en la integridad estructural y funcional de la retina. El mismo presenta diferentes mutaciones que generan pérdida de función de la proteína. La sospecha diagnóstica se basa en la clínica y los antecedentes familiares, y se apoya en la paraclínica confirmándose en la mayoría de los casos mediante secuenciación del gen. El tratamiento consiste en control periódico oftalmológico y cirugía de las complicaciones. Presentamos el caso de un niño de 2 años con episodios reiterados de desprendimiento de retina, con antecedentes familiares de Retinosquisis por línea materna en individuos de sexo masculino. Estos fueron estudiados demostrándose que son portadores de la variante probablemente patogénica c.466A>C (Arg156Gly) en el gen RS1 la cual había sido reportada previamente en una familia de origen chino. Se demostró que nuestro paciente presenta la mutación familiar en hemicigosis, por lo que esta es la segunda familia en que se confirma la segregación de esta variante con Retinosquisis.


X-linked Retinoschisis is a genetic disease characterized by reduced visual acuity mainly in men due to juvenile macular degeneration. Its prevalence is 1/5000 men worldwide. It manifests from the first decade of life with loss of vision that progresses to adolescence and then remains stable until the 4th decade of life, when it may present a significant decline. The fundus exam usually shows schism. Carrier women rarely have symptoms. The gene involved is RS1 (Xp22.13), which encodes for Retinoschisin, a protein that participates in the structural and functional integrity of the retina. In affected cases, mutations that generate loss of protein function were demonstrated. The diagnosis is based on the clinical and family history, and is supported by ophthalmology evaluation; in most cases it can be confirmed by sequencing of the gene. The treatment consists of periodic ophthalmological control and surgery of the complications. We describe the case of a 2 year old boy with repeated episodes of retinal detachment and who has a family history of Retinoschisis by maternal line in male individuals. These were studied, and it was shown that they are carriers of the probably pathogenic variant c.466A> C (Arg156Gly) in the RS1 gene, which had been reported previously in a family of Chinese origin. It was shown that our patient presents the family mutation in hemizygous state, so this is the second family in which the segregation of this variant with Retinoschisis is confirmed.


A retinosquise ligada ao X, que ocorre principalmente em homens, é uma doença genética caracterizada pela redução da acuidade visual devido à degeneração macular. Sua prevalência é de 1/5000 homens em todo o mundo. Manifesta-se desde a primeira década de vida com perda da visão que progride até a adolescência e permanece estável até a 4ª década de vida, época em que apresenta declínio significativo. O fundo geralmente mostra esquise. Portadoras do sexo feminino raramente apresentam sintomas. O gene envolvido é o RS1, que codifica a Retinosquina, proteína que participa da integridade estrutural e funcional da retina. Apresenta diferentes mutações que geram perda de função da proteína. A suspeita diagnóstica baseia-se na história clínica e familiar, e na paraclínica, sendo confirmada na maioria dos casos pelo sequenciamento gênico. O tratamento consiste em acompanhamento oftalmológico periódico e cirurgia para complicações. Apresentamos o caso de um menino de 2 anos com episódios repetidos de descolamento de retina, com história familiar de retinosquise materna no sexo masculino. Estes foram estudados mostrando que são portadores da variante provavelmente patogênica c.466A> C (Arg156Gly) no gene RS1, que havia sido relatado anteriormente em uma família de origem chinesa. Foi demonstrado que nosso paciente apresenta a mutação familiar em hemizigose, sendo esta a segunda família em que se confirma a segregação desta variante com Retinosquise.


Assuntos
Humanos , Masculino , Lactente , Retinosquise/genética , Retinosquise/diagnóstico por imagem , Proteínas do Olho/genética , Mutação
4.
Rev. chil. pediatr ; 90(4): 443-447, ago. 2019. graf
Artigo em Espanhol | LILACS, UY-BNMED, BNUY | ID: biblio-1020653

RESUMO

INTRODUCCIÓN: Osteopetrosis Infantil Maligna (OIM) es un grave e inusual desorden genético debi do a una actividad osteoclástica anormal. OBJETIVO: Reportar lactante en quien se documentó una Osteopetrosis Infantil Maligna, revisando aspectos diagnósticos y terapéuticos más relevantes. CASO CLÍNICO: Reportamos un lactante de 10 meses de sexo masculino en quien se confirmó OIM tras presentar plaquetopenia y visceromegalias. En su historial destacó ser primer hijo de padres no consanguíneos, y entre sus hallazgos presentó hepatoesplenomegalia, plaquetopenia y anemia graves, compromiso sensorial visual y auditivo e infecciones a repetición. El diagnóstico fue confirmado mediante estudio genético, el cual identificó 2 mutaciones heterocigotas en el gen TCIRG1. Se rea lizó trasplante de precursores hematopoyéticos, sin haber presentado recuperación hematológica, falleciendo por enfermedad veno oclusiva. DISCUSIÓN: La OIM es una enfermedad inusual, grave y de inicio temprano, siendo necesario un elevado índice de sospecha ante hepatoesplenomegalia y falla medular. El diagnóstico temprano y el trasplante de precursores hematopoyéticos son las únicas intervenciones potencialmente curativas de esta entidad letal.


INTRODUCCIÓN: Malignant Infantile Osteopetrosis (MIOP) is a rare and severe genetic disorder due to abnormal osteoclast activity. OBJECTIVE: To report an infant who presented Malignant Infantile Osteopetrosis, reviewing the most relevant diagnostic and therapeutic aspects. CLINICAL CASE: A ten- month-old male infant with diagnosis of MIOP confirmed after presenting thrombocytopenia and visceromegaly. He was the first child of non-consanguineous parents, and among the findings, he presented severe hepatosplenomegaly, thrombocytopenia, and anemia; visual and hearing impairment, and repeated infections. The diagnosis was confirmed by genetic study, which identified two heterozygous mutations in the TCIRG1 gene. Hematopoietic stem cells were transplanted without hematological recovery. The patient died due to occlusive venous disease. DISCUSSION: MIOP is a rare, severe, and early-onset disease, with a high rate of suspicion necessary in the presence of hepatosplenomegaly and bone marrow failure. Early diagnosis and hematopoietic stem cells transplanta tion are the only potentially therapeutic interventions of this lethal entity.


Assuntos
Humanos , Masculino , Lactente , Osteopetrose/diagnóstico , Transplante de Células-Tronco Hematopoéticas/métodos , ATPases Vacuolares Próton-Translocadoras/genética , Osteoporose/fisiopatologia , Osteoporose/genética , Evolução Fatal , Mutação
7.
Nephrol Dial Transplant ; 21(2): 431-6, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16249199

RESUMO

BACKGROUND: The problem of pure red cell aplasia (PRCA) prompted nephrologists to revert to a wider intravenous (i.v.) utilization of erythropoeitin (Epo). Once weekly i.v. Epo administration has been suggested to be as effective as the twice/thrice weekly i.v. dose. The aim of the present study was to test whether once weekly i.v. Epo administration is equally as cost-effective as once weekly subcutaneous (s.c.) and 2-3 times weekly i.v. administration. METHODS: We prospectively studied 41 patients (23 males, aged 28-82 years), on renal replacement therapy for 18-286 months, stabilized on twice or thrice weekly s.c. Epo-alpha (basal). The patients were treated for three consecutive 6 month periods with once weekly s.c. (OWSC), once weekly i.v. (OWIV) and twice/thrice weekly i.v. (TWIV) Epo-alpha. The initial dose for each period was equal to the final dose of the previous one; when necessary, the dose was adjusted according to DOQY guidelines. Iron, folic acid and vitamin B(12) supplementations were given throughout all the study periods. At the end of each of the four study periods, the following parameters were evaluated: haemoglobin, haematocrit, hypochromic red blood cells (RBCs), iron, serum ferritin, transferrin, folate, vitamin B(12), C-reactive protein (CRP), Kt/V, parathyroid hormone (PTH) and weekly dose of Epo-alpha. RESULTS: Thirty-three out of 41 enrolled patients completed the study (there were five deaths, two renal transplants and one transfer). No significant changes were observed as regards iron, serum ferritin, transferrin, folate, vitamin B(12), CRP, Kt/V or PTH level. Haemoglobin levels were not different at the end of the basal (11.7+/-1.21), OWSC (11.8+/-0.86) and TWIV (12.1+/-1.04) periods, while significantly lower levels were observed after the OWIV period (11.0+/-0.97, P<0.01). Weekly Epo consumption (Epo U/week/kg body weight/g haemoglobin) was: basal 11.57+/-5.96; OWSC 10.22+/-4.53; OWIV 15.99+/-7.7*(a); and TWIV 11.89+/-6.3*(a) (*P<0.01 vs basal; (a)P<0.01 vs OWSC). CONCLUSIONS: From our results, the OWIV schedule seems to have less efficacy in the control of anaemia of chronic renal failure patients on dialysis treatment than either OWSC or TWIV schedules.


Assuntos
Eritropoetina/administração & dosagem , Hematínicos/administração & dosagem , Aplasia Pura de Série Vermelha/tratamento farmacológico , Diálise Renal , Adulto , Idoso , Idoso de 80 Anos ou mais , Esquema de Medicação , Epoetina alfa , Feminino , Humanos , Injeções Intravenosas , Injeções Subcutâneas , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Proteínas Recombinantes
8.
Folha méd ; 100(1/2): 11-2, jan.-fev. 1990. ilus
Artigo em Português | LILACS | ID: lil-88842

RESUMO

Scwanoma ou neurilemoma é um tumor neural benigno derivado das células de Schwann. O sítio mais comum de tumores neurais intrá-ósseos é a mandíbula. Este tumor pode ser assintomático ou pode causar dor ou parestesia, e geralmente é de crescimento lento. Radiograficamente, o neurilemoma central pode aparecer como uma lesäo radiolucente cística ou multilocular. O tratamento é uma enucleaçäo cirúrgica conservadora completa e acompanhamento periódico do paciente


Assuntos
Adulto , Humanos , Masculino , Mandíbula , Neurilemoma , Tumores Odontogênicos , Radiografia Panorâmica , Células de Schwann
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