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1.
Cureus ; 16(2): e53522, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38445165

RESUMO

This is a case of a 37-year-old female patient with past medical history of mitral valve prolapse and benign mesothelial pericardial cyst status post laparoscopic resection who presented to the emergency department with a chief complaint of right-sided sharp non-radiating chest pain due to recurrent case of benign mesothelial pericardial cyst. Though this is not a common pathology, it does overlap with common cardiovascular symptoms/conditions; not limited to but including chest pain, dyspnea, palpitations, pericardial effusions, infections and arrhythmias. It is crucial to have appropriate history and physical exam and appropriate evaluation to rule out pericardial cysts as well as their locations and their potential lethal mechanical implication on crucial nearby structures. This is significant in order to avoid uncommon but lethal cardiac complications in this condition such as cardiac arrhythmias, cardiac tamponade, right ventricular outflow tract and even sudden cardiac death.

2.
Biomedicines ; 11(7)2023 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-37509603

RESUMO

Fibromyalgia syndrome (FMS) is a chronic widespread pain syndrome that is accompanied by fatigue, sleep disturbances, anxiety, depression, lack of concentration, and neurocognitive impairment. As the currently available drugs are not completely successful against these symptoms and frequently have several side effects, many scientists have taken on the task of looking for nonpharmacological remedies. Many of the FMS-related symptoms have been suggested to be associated with an altered pattern of endogenous melatonin. Melatonin is involved in the regulation of several physiological processes, including circadian rhythms, pain, mood, and oxidative as well as immunomodulatory balance. Preliminary clinical studies have propounded that the administration of different doses of melatonin to patients with FMS can reduce pain levels and ameliorate mood and sleep disturbances. Moreover, the total antioxidant capacity, 6-sulfatoxymelatonin and urinary cortisol levels, and other biological parameters improve after the ingestion of melatonin. Recent investigations have proposed a pathophysiological relationship between mitochondrial dysfunction, oxidative stress, and FMS by looking at certain proteins involved in mitochondrial homeostasis according to the etiopathogenesis of this syndrome. These improvements exert positive effects on the quality of life of FMS patients, suggesting that the use of melatonin as a coadjuvant may be a successful strategy for the management of this syndrome.

3.
Front Immunol ; 14: 1171065, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37275882

RESUMO

Background: Neutrophils, key players of the immune system, also promote tumor development through the formation of neutrophil extracellular traps (NETs) in a process called NETosis. NETs are extracellular networks of DNA, histones and cytoplasmic and granular proteins (calprotectin, myeloperoxidase, elastase, etc.) released by neutrophils upon activation. NETs regulate tumor growth while promoting angiogenesis and invasiveness, and tumor cells also stimulate NETosis. Although NETosis seems to be increased in cancer patients, an increase of NETs in plasma may also be mediated by an impaired degradation by plasma DNaseI, as evidenced in several immunological disorders like lupus nephritis. However, this has never been evidenced in bladder cancer (BC) patients. Herein, we aimed to evaluate the occurrence of increased NETosis in plasma and tumor tissue of BC patients, to ascertain whether it is mediated by a reduced DNaseI activity and degradation, and to in vitro explore novel therapeutic interventions. Methods: We recruited 71 BC patients from whom we obtained a plasma sample before surgery and a formalin-fixed paraffin embedded tumor tissue sample, and 64 age- and sex-matched healthy controls from whom we obtained a plasma sample. We measured NETs markers (cell-free fDNA, calprotectin, nucleosomes and neutrophil elastase) and the DNaseI activity in plasma with specific assays. We also measured NETs markers in BC tissue by immunofluorescence. Finally, we evaluated the ability of BC and control plasma to degrade in vitro-generated NETs, and evaluated the performance of the approved recombinant human DNaseI (rhDNaseI, Dornase alfa, Pulmozyme®, Roche) to restore the NET-degradation ability of plasma. In vitro experiments were performed in triplicate. Statistical analysis was conducted with Graphpad (v.8.0.1). Results: NETosis occurs in BC tissue, more profusely in the muscle-invasive subtype (P<0.01), that with the worst prognosis. Compared to controls, BC patients had increased NETosis and a reduced DNaseI activity in plasma (P<0.0001), which leads to an impairment to degrade NETs (P<0.0001). Remarkably, this can be therapeutically restored with rhDNaseI to the level of healthy controls. Conclusion: To the best of our knowledge, this is the first report demonstrating that BC patients have an increased NETosis systemically and in the tumor microenvironment, in part caused by an impaired DNaseI-mediated NET degradation. Remarkably, this defect can be therapeutically restored in vitro with the approved Dornase alfa, thus Pulmozyme® could become a potential therapeutic tool to locally reduce BC progression.


Assuntos
Armadilhas Extracelulares , Neoplasias da Bexiga Urinária , Humanos , Armadilhas Extracelulares/metabolismo , Neutrófilos/metabolismo , Histonas/metabolismo , Nucleossomos/metabolismo , Neoplasias da Bexiga Urinária/terapia , Neoplasias da Bexiga Urinária/metabolismo , Microambiente Tumoral
4.
5.
Int J Mol Sci ; 24(6)2023 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-36983067

RESUMO

Neutrophils, the most abundant circulating leukocytes, play a well-known role in defense against pathogens through phagocytosis and degranulation. However, a new mechanism involving the release of neutrophil extracellular traps (NETs) composed of DNA, histones, calprotectin, myeloperoxidase, and elastase, among others, has been described. The so-called NETosis process can occur through three different mechanisms: suicidal, vital, and mitochondrial NETosis. Apart from their role in immune defense, neutrophils and NETs have been involved in physiopathological conditions, highlighting immunothrombosis and cancer. Notably, neutrophils can either promote or inhibit tumor growth in the tumor microenvironment depending on cytokine signaling and epigenetic modifications. Several neutrophils' pro-tumor strategies involving NETs have been documented, including pre-metastatic niche formation, increased survival, inhibition of the immune response, and resistance to oncologic therapies. In this review, we focus on ovarian cancer (OC), which remains the second most incidental but the most lethal gynecologic malignancy, partly due to the presence of metastasis, often omental, at diagnosis and the resistance to treatment. We deepen the state-of-the-art on the participation of NETs in OC metastasis establishment and progression and their involvement in resistance to chemo-, immuno-, and radiotherapies. Finally, we review the current literature on NETs in OC as diagnostic and/or prognostic markers, and their contribution to disease progression at early and advanced stages. The panoramic view provided in this article might pave the way for enhanced diagnostic and therapeutic strategies to improve the prognosis of cancer patients and, specifically, OC patients.


Assuntos
Armadilhas Extracelulares , Neoplasias Ovarianas , Humanos , Feminino , Neutrófilos , Histonas , Atenção , Microambiente Tumoral
6.
Front Immunol ; 14: 1111344, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36817483

RESUMO

Introduction: High-grade serous ovarian cancer (HGSOC) is the second most frequent gynecological malignancy but the most lethal, partially due to the spread of the disease through the peritoneal cavity. Recent evidence has shown that, apart from their role in immune defense through phagocytosis and degranulation, neutrophils are able to participate in cancer progression through the release of neutrophil extracellular traps (NETs) in a process called NETosis. NETs are composed of DNA, histones, calprotectin, myeloperoxidase (MPO) and elastase and the NETosis process has been proposed as a pre-requisite for the establishment of omental metastases in early stages of HGSOC. Nevertheless, its role in advanced stages remains to be elucidated. Therefore, our principal aim is to characterize a NETosis biomarker profile in biofluids from patients with advanced HGSOC and control women. Methods: Specifically, five biomarkers of NETosis (cell-free DNA (cfDNA), nucleosomes, citrullinated histone 3 (citH3), calprotectin and MPO) were quantified in plasma and peritoneal fluid (PF) samples from patients (n=45) and control women (n=40). Results: Our results showed that HGSOC patients presented a higher concentration of cfDNA, citH3 and calprotectin in plasma and of all five NETosis biomarkers in PF than control women. Moreover, these biomarkers showed a strong ability to differentiate the two clinical groups. Interestingly, neoadjuvant treatment (NT) seemed to reduce NETosis biomarkers mainly systemically (plasma) compared to the tumor environment (PF). Discussion: In conclusion, NETosis biomarkers are present in the tumor environment of patients with advanced HGSOC, which might contribute to the progression of the disease. Besides, plasma cfDNA and calprotectin could represent minimally invasive surrogate biomarkers for HGSOC. Finally, NT modifies NETosis biomarkers levels mainly at the systemic level.


Assuntos
Ácidos Nucleicos Livres , Armadilhas Extracelulares , Neoplasias Ovarianas , Humanos , Feminino , Neutrófilos , Histonas , Biomarcadores
7.
Clin Infect Dis ; 72(Suppl 3): S146-S151, 2021 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-33905480

RESUMO

BACKGROUND: The gambiense human African trypanosomiasis (gHAT) elimination programme in the Democratic Republic of Congo (DRC) routinely collects case data through passive surveillance and active screening, with several regions reporting no cases for several years, despite being endemic in the early 2000s. METHODS: We use mathematical models fitted to longitudinal data to estimate the probability that selected administrative regions have already achieved elimination of transmission (EOT) of gHAT. We examine the impact of active screening coverage on the certainty of model estimates for transmission and therefore the role of screening in the measurement of EOT. RESULTS: In 3 example health zones of Sud-Ubangi province, we find there is a moderate (>40%) probability that EOT has been achieved by 2018, based on 2000-2016 data. Budjala and Mbaya reported zero cases during 2017-18, and this further increases our respective estimates to 99.9% and 99.6% (model S) and to 87.3% and 92.1% (model W). Bominenge had recent case reporting, however, that if zero cases were found in 2021, it would substantially raise our certainty that EOT has been met there (99.0% for model S and 88.5% for model W); this could be higher with 50% coverage screening that year (99.1% for model S and 94.0% for model W). CONCLUSIONS: We demonstrate how routine surveillance data coupled with mechanistic modeling can estimate the likelihood that EOT has already been achieved. Such quantitative assessment will become increasingly important for measuring local achievement of EOT as 2030 approaches.


Assuntos
Tripanossomíase Africana , Animais , República Democrática do Congo , Humanos , Programas de Rastreamento , Probabilidade , Trypanosoma brucei gambiense
8.
Rev. latinoam. cienc. soc. niñez juv ; 19(1): 224-250, ene.-abr. 2021. tab
Artigo em Espanhol | LILACS | ID: biblio-1251884

RESUMO

Resumen (analítico) Este artículo recoge los hallazgos de una investigación sobre las prácticas de resistencia y re-existencia presentes en la acción colectiva juvenil desplegada en Riosucio (Caldas), zona rural afectada por el conflicto armado colombiano. Tuvo como objetivo analizar los modos en que la acción colectiva juvenil construye horizontes de paz en tiempos del posacuerdo. La investigación es cualitativa etnográfica e incorpora la etnografía visual; colaboraron cuatro colectivos juveniles con quienes además se elaboró una pieza fílmica documental. Como principales conclusiones se plantea: el surgimiento de los colectivos como apuesta a las violencias que reconocen en el territorio local y nacional, así como el potencial del arte como mecanismo de resistencia y re-existencia para la construcción de paz en lo rural, epicentro histórico de la guerra en la país.


Abstract (analytical) This article collects the findings of a research of the practices of resistance and re-existence present in the youth collective action deployed in Riosucio (Caldas), a rural area affected by the Colombian armed conflict. Its purpose was to analyze the ways in which collective action youth builds peaceful horizons in times of post-agreement. The research is qualitative ethnographic and incorporates visual ethnography; four youth collectives collaborated and also elaborated a documentary film material. The main conclusions are: the surge of these collectives as a wager to the multiple violences they recognize in their local and national territory, and the potential of art as means of resistance and re-existance for the construction of peace in the rural area, the historical epicenter of the war in the country.


Resumo (analítico) Este artigo reúne os resultados de uma investigação sobre as práticas de resistência e de reexistên-cia presentes na ação coletiva juvenil implantada em Riosucio (Caldas), área rural afetada pelo conflito armado colombiano. Com o objetivo de analisar os modos de ação coletiva a juventude constrói horizontes de paz em tempos de pós-acordo. A pesquisa é qualitativa etnográfica e incorpora etnografia visual; Colaboraram quatro grupos de jovens com os quais também foi produzido um documentário. As principais conclusões são: a emergência dos grupos como aposta na violência que reconhecem no território local e nacional; e a potencialidade da arte como mecanismo de resistência e de reexistência para a construção da paz no campo, epicentro histórico da guerra no país.


Assuntos
Violência , Conflitos Armados , Pesquisa
9.
Complement Ther Clin Pract ; 35: 170-176, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31003653

RESUMO

OBJECTIVES: To know the effectiveness and safety of non-supervised breathing exercise regimen by promoting patients' self-management, and to investigate if non-supervised breathing exercise regimen shows similar benefits to supervised regimen in improving pain and fibromyalgia (FM) impact on daily life. MATERIAL AND METHODS: Fifty-one women with FM were assigned to: supervised breathing exercise regimen group, non-supervised breathing exercise regimen group, and control group. Pain thresholds tolerance on tender points and FM impact on daily life were evaluated. RESULTS: After 12-weeks of breathing exercises statistical differences were not found between supervised and non-supervised regimen. However, supervised regimen showed additional improvements in pain thresholds tolerance and in pain-FIQ subscale. CONCLUSION: Our results suggest that performing a non-supervised breathing exercise program could be as safe and effective as the supervised regimen. However, it was observed that there could be a tendency of supervised exercise regimen to show additional benefits in terms of pain.


Assuntos
Exercícios Respiratórios/métodos , Fibromialgia/terapia , Adulto , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Medição da Dor , Limiar da Dor , Resultado do Tratamento
10.
Rev Fac Cien Med Univ Nac Cordoba ; 74(4): 393-397, 2017 12 14.
Artigo em Espanhol | MEDLINE | ID: mdl-29902149

RESUMO

Kaposi's sarcoma is a limphoangioproliferous tumor described for the first time in the year 1872 by Moritz Kaposi. There are four clinical variants, the classical form, the endemic, the iatrogenic associated to transplantation or immunosuppression and the epidemic associated with AIDS, which will be referred in this publication. In this research,(case, paperwork, investigation) a 31 year old male patient, who was diagnosed AIDS and Kaposi's sarcoma at the same time while in hospital, is described.


El sarcoma de Kaposi es un tumor linfoangioproliferativo descripto por primera vez en el año 1872 por Moritz Kaposi. Hay cuatro variantes clínicas, la forma clásica, la endémica, la iatrogénica asociada a trasplante o inmunosupresión y la epidémica asociada a SIDA, de la cual se hará referencia en esta publicación. Se describe un paciente varón de 31 años, al cual durante la misma internación se hace el diagnóstico de SIDA y de sarcoma de Kaposi.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/diagnóstico , Infecções por HIV/diagnóstico , Sarcoma de Kaposi/diagnóstico , Neoplasias Cutâneas/diagnóstico , Adulto , Braço , Diagnóstico Tardio , Diagnóstico Diferencial , Humanos , Masculino , Sarcoma de Kaposi/patologia , Sarcoma de Kaposi/fisiopatologia , Neoplasias Cutâneas/patologia , Neoplasias Cutâneas/fisiopatologia
12.
Salud UNINORTE ; 30(3): 431-441, sep.-dic. 2014. ilus, tab
Artigo em Espanhol | LILACS-Express | LILACS | ID: lil-747689

RESUMO

Objetivo: Describir el significado de la experiencia de infligir dolor de los enfermeros en formación matriculados en el Programa de Enfermería de la Facultad de Ciencias de la Salud de la Universidad del Tolima (Colombia). Materiales y métodos: Se realizó una investigación con enfoque fenomenológico durante el semestre académico A 2012 (comprendido entre enero a junio). En la muestra participaron deforma voluntaria, luego de conocer la naturaleza y propósitos del estudio, 14 estudiantes, cuyas edades oscilaron entre 17 y 23 años. Se les aplicó una entrevista en profundidad de forma individual. Resultados: La experiencia expresada por los estudiantes permitió identificar dos categorías: las vivencias y las estrategias de afrontamiento ante la situación. Conclusión: La experiencia de causar dolor vivida por el enfermero novato difiere de la del enfermero experto según el estudio realizado por Madjar. La investigación demostró la necesidad de incluir en el currículo del Programa de Enfermería actividades que fomenten el desarrollo de estrategias de afrontamiento a partir de la aplicación de metodologías que le permitan al docente identificar las respuestas humanas del estudiante ante situaciones de estrés. Así como el estudiante interpreta los códigos de comunicación no verbal del otro, el sujeto de cuidado también descubre en su cuidador ese cúmulo de emociones, sentimientos, temores, y hasta logra interpretar en algunos casos el nivel de conocimiento que aflora durante su encuentro.


Objective: To describe the meaningfulness of the experience of inflicting pain of the nurses enrolled in the nursing program at the Faculty of Health Sciences of the University ofTolima. Materials and methods: The research was conducted using a phenomenological approach, during the academic semester A 2012 (from January to June). After learning the nature and purpose of the study, a sample of 14 students, whose ages ranged between 17 and 23 years, participated voluntarily. They were applied a depth interview individually. Results: The experience expressed by students identified two categories; experiences and strategies for coping with the situation. Conclusion: The experience of causing pain lived by the novice nurse differs from that of the expert nurse according to a study by Madjar. The research demonstrated the need to include in the curriculum of the Nursing Program, activities that promote the development of coping strategies, from the application of methodological strategies that enable teachers to identify students' human responses to stressful situations. As well as the student interprets codes of nonverbal communication expressed by her patient: the latter also discovers in his caretaker a cluster of emotions, feelings , fears, and even manages to interpret, in some cases, the level of knowledge that emerges during their encounter.

13.
Rev. argent. mastología ; 33(118): 39-44, Abr. 2014. graf
Artigo em Espanhol | LILACS | ID: lil-726104

RESUMO

Objetivo: Mostrar nuestra experiencia inicial del equipo de trabajo del consultorio de Patología Mamaria del Hospital Regional Español de la ciudad de Bahía Blanca, en la realización de biopsias radioquirúrgicas (BRQ) y analizar la proporción de carcinomas mamarios encontrados. Material y métodos: Se realizó un estudio retrospectivo de las 742 consultas en el período comprendido entre marzo de 2008 y junio de 2012, de las cuales 41 pacientes fueron sometidas a biopsias radioquirúrgicas por presentar lesión no palpable con imagen mamográfica de sospecha. Se incluyeron todas aquellas pacientes que concurrían con imagen mamográfica no palpable, se realizó en todas las pacientes marcación mamográfica con arpón Mamawire Plus 206A, con control intraquirúrgico. Las variables que se analizaron fueron la edad, motivo de consulta, antecedente familiar o personal de cáncer de mama, tipo de lesión mamográfica, examen clínico mamario y resultado de anatomía patológica. Resultados: En dicho período se analizaron 41 biopsias radioquirúrgicas, de las cuales el 31,7% correspondieron a carcinomas mamarios. El rango de edad de las pacientes fue de 33 a 82 años, con un promedio de 63 años. Los motivos de consulta por los que concurrieron al consultorio de Patología Mamaria fueron control en 24 pacientes y por derivación en 15 pacientes. Dentro de los antecedentes familiares de cáncer de mama 12 pacientes no presentaban, 10 pacientes tenían datos positivos familiares y 5 pacientes positivos personales; y 14 pacientes sin datos, dentro de las que se incluyen aquellas que no los conocían. Respecto a la patología benigna, el diagnóstico más frecuente fue el de enfemedad fibroquística con 7 casos (17,00%); y con respecto a la patología maligna, carcinoma ductal in situ en 3 casos (7,31%) y carcinoma ductal invasivo en 10 casos (24,40%).


Assuntos
Biópsia , Neoplasias da Mama , Mamografia
14.
Proc Natl Acad Sci U S A ; 110(51): E4978-86, 2013 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-24297935

RESUMO

Ascites tumor cells (ATCs) represent a potentially valuable source of cells for monitoring treatment of ovarian cancer as it would obviate the need for more invasive surgical biopsies. The ability to perform longitudinal testing of ascites in a point-of-care setting could significantly impact clinical trials, drug development, and clinical care. Here, we developed a microfluidic chip platform to enrich ATCs from highly heterogeneous peritoneal fluid and then perform molecular analyses on these cells. We evaluated 85 putative ovarian cancer protein markers and found that nearly two-thirds were either nonspecific for malignant disease or had low abundance. Using four of the most promising markers, we prospectively studied 47 patients (33 ovarian cancer and 14 control). We show that a marker set (ATCdx) can sensitively and specifically map ATC numbers and, through its reliable enrichment, facilitate additional treatment-response measurements related to proliferation, protein translation, or pathway inhibition.


Assuntos
Ascite/metabolismo , Biomarcadores Tumorais/metabolismo , Técnicas Analíticas Microfluídicas , Proteínas de Neoplasias/metabolismo , Neoplasias Ovarianas/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Ascite/patologia , Biópsia , Feminino , Humanos , Pessoa de Meia-Idade , Neoplasias Ovarianas/patologia
15.
PLoS One ; 8(5): e64094, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23675521

RESUMO

PURPOSE: To investigate the in vitro effect of four vital dyes on toxicity and apoptosis in a human retinal pigment epithelial (RPE) cell line. METHODS: ARPE-19 cells were exposed to brilliant blue (BriB), methyl blue (MetB), acid violet (AcV) and indocyanine green (ICG). Balanced salt solution was used as control. Five different concentrations of each dye (1, 0.5, 0.25, 0.05 and 0.005 mg/mL) and two exposure times (3 and 30 min) were tested. Cell viability was determined by cell count and MTS assay and cell toxicity by LDH assay. Real-time PCR and Western blotting were used to access the apoptosis process. RESULTS: ICG significantly reduced cell viability after 3 minutes of exposure at all concentrations (p<0.01). BriB was safe at concentrations up to 0.25 mg/mL and MetB at concentrations up to 0.5 mg/mL, while AcV was safe up to 0.05 mg/ml, after 3 minutes of exposure. Toxicity was higher, when the cells were treated for 30 minutes. Expression of Bax, cytochrome c and caspase-9 was upregulated at the mRNA and protein level after ICG exposure, while Bcl-2 was downregulated. AcV and MetB were similar to control. However, BriB resulted in upregulation of Bcl-2, an antiapoptotic protein. CONCLUSIONS: The safest dye used on RPE cells was MetB followed by BriB and AcV. ICG was toxic at all concentrations and exposure times tested. Moreover, ICG was the only dye that induced apoptosis in ARPE-19 cells. BriB significantly increased Bcl-2 protein levels, which might protect against the apoptosis process.


Assuntos
Apoptose/efeitos dos fármacos , Corantes/toxicidade , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Epitélio Pigmentado da Retina/citologia , Transdução de Sinais/efeitos dos fármacos , Benzenossulfonatos/toxicidade , Caspase 9/metabolismo , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Citocromos c/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Verde de Indocianina/toxicidade , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Epitélio Pigmentado da Retina/efeitos dos fármacos , Epitélio Pigmentado da Retina/metabolismo , Proteína X Associada a bcl-2/genética , Proteína X Associada a bcl-2/metabolismo
16.
Rev. colomb. quím. (Bogotá) ; 42(1): 64-85, Jan.-Apr. 2013. ilus
Artigo em Espanhol | LILACS | ID: lil-729600

RESUMO

Óxidos mixtos de manganeso y cobalto, con relaciones molares M²++Mg2+ /M3+=3 y M2+/ Mg2+=1, fueron preparados por el método de coprecipitación. Los sólidos fueron caracterizados mediante las técnicas de difracción de rayos X (XRD), temperatura programada de reducción (TPR-H2) y adsorción de N2 en área superficial; éstos fueron empleados para la oxidación catalítica de una mezcla de dos compuestos orgánicos representativos de COVs: el tolueno y el 2-propanol. El óxido mixto de manganeso logró el 100% de oxidación de la mezcla de COVs, mientras que el óxido mixto de cobalto no alcanzó una oxidación total. El catalizador Mn-Mg-Al presentó las menores temperaturas de oxidación de tolueno y 2-propanol en la mezcla, haciéndolo el catalizador más eficiente. El desempeño catalítico superior de dicho óxido se asocia principalmente con su mejor comportamiento redox, comparado con el del óxido de cobalto. Con el fin de evaluar el efecto de la composición del reactivo, se estudió la oxidación catalítica individual de tolueno y 2-propanol sobre el óxido mixto de manganeso. El catalizador fue activo en la oxidación de los dos COVs individuales, pero el tolueno fue el compuesto más difícil de oxidar. Dicho catalizador mostró 100% de conversión del tolueno hacia CO2, mientras que el 2-propanol produjo primero acetona, la cual posteriormente fue oxidada hasta CO2. Las temperaturas de oxidación de los componentes en la mezcla de COVs fueron superiores que en la conversión individual de tolueno y 2-propanol. Este resultado sugiere un posible efecto inhibitorio en la oxidación de 2-propanol cuando se tienen mezclas de los COVs.


Manganese and cobalt mixed oxides with M2++Mg2+/M3+=3 y M2+/Mg2+=1 ratios were obtained by the coprecipitation method. The solids were characterized using X-ray diffraction (XRD), temperature-programmed reduction (H2-TPR), N2 adsorption and in the catalytic oxidation of two VOCs: toluene and 2-propanol. Manganese mixed oxide reached 100% conversion of the mixture of VOCs while cobalt mixed oxide did not achieve a complete oxidation. The catalyst Mn-Mg-Al showed the lowest temperature oxidation of toluene and 2-propanol in the mixture. The highest performance of the oxide catalyst Mn-Mg-Al is associated with the better redox potential in the manganese catalyst. Manganese mixed oxide was active in the oxidation of the single VOCs, where the scale of difficulty to oxidize the different organic compounds evaluated was: 2-propanol < toluene. The mixed oxide showed 100% conversion to CO2 in the oxidation of toluene, while the 2-propanol was first oxidized to acetone. It suggests that there is an inhibitory effect on the oxidation of 2-propanol in the mixture of VOCs.


Óxidos mistos de cobalto e manganês com relações M2++Mg2+/M3+=3 y M2+/ Mg2+=1 foram preparados pelo método de coprecipitação. Os sólidos foram caracterizados pelas técnicas de difração de raios-X (XRD), temperatura programada de redução (TPR-H2), área superficial adsorção do N2 e na oxidação catalítica de dois compostos orgânicos representativos (COVs): tolueno e 2-propanol. O catalisador Mn-Mg- Al apresentou as menores temperaturas de oxidação da mistura, fazendo-lo o catalisador mais eficiente. O desempenho catalítico superior do óxido Mn-Mg-Al está associado principalmente a seu melhor desempenho redox em comparação com o óxido de cobalto. Mn-Mg-Al catalisador foi ativo na oxidação dos dois individuais COVs, sendo o tolueno o composto mais difícil de oxidar seguido do 2-propanol. Óxidos mistos de manganês mostro 100% de conversão até CO2 para tolueno, enquanto que o 2-propanol produz em primeiro lugar acetona, que posteriormente é oxidada a CO2. Temperaturas de oxidação dos componentes da mistura de compostos orgânicos voláteis é maior do que a única conversão de tolueno e 2-propanol. Este resultado sugeriu um possível efeito inibitório sobre a oxidação de 2-propanol ao ter misturas de COV.

17.
Rev. biol. trop ; Rev. biol. trop;60(4): 1707-1719, Dec. 2012. graf, tab
Artigo em Espanhol | LILACS | ID: lil-662242

RESUMO

Mangrove deforestation is widespread in the Greater Caribbean but its impact on macrobenthos has not been evaluated to date. In order to assess the impact of mangrove conversion to pasture, densities and shell sizes of two dominant gastropods (Neritina virginea and Melampus coffeus) were compared among four mangrove types: 1) Rhizophora mangle-dominated fringing mangroves, 2) Avicennia germinans-dominated basin mangroves, 3) Mixed-species basin mangroves, and 4) A. germinansbasin mangroves converted to pastures, in the Turbo River Delta (Urabá Gulf, Colombia). Mangrove types were polygon-delimited with satellite images and color aerial photographs were taken in 2009. various (n<5) polygons per mangrove type were sampled in January, July and December 2009, and a total (n<20) 0.025m²-quadrats were randomly placed along each polygon. Forest structure variables, pore-water physico-chemical variables and sediment-grain metrics were measured in the four mangrove types. Mean density and size of both gastropod species were measured. The results showed that the mean density and size of both species were significantly greater in R. mangle-fringing mangroves. N. virginea density decreased gradually towards the A. germinans-basin mangroves seemly related to the diadromous life-history. This species nearly disappeared in the neighboring pastures because individuals were constrained to a few remaining flooded areas. In the pastures, M. coffeus individuals were clumped in the remaining A. germinans trees due to its climbing behavior as a pulmonate. We hypothesize that the decline of these two gastropods was related to physical microhabitat (e.g. trees, prop roots, and seedlings) degradation, and alteration of soil properties (e.g. temperature, pH, organic matter content). Finally, we also hypothesize that the local extinction of N. virginea due to clear-cutting may exert strong negative effects on the ecosystem function because it is a dominant omnivore.


El delta del río Turbo es una de las áreas del golfo de Urabá, Colombia donde la tala de manglar es más extensa y activa, por lo tanto, se evaluó el impacto de la conversión de manglar a potrero, comparando la densidad y talla promedio de dos gasterópodos (Neritina virginea y Melampus coffeus), variables dasonómicas, físico-químicas intersticiales y granulométricas del suelo entre varios parches de: 1) manglar de franja, 2) manglar de cuenca, 3) manglar de cuenca mixto y 4) manglar de cuenca convertido a potrero, en el delta del río Turbo de este golfo, entre enero y diciembre 2009. Las densidades y tallas de los gasterópodos fueron mayores en el manglar de franja. N. virginea fue muy abundante pero disminuyó hacia el manglar de cuenca (debido a sus hábitos diádromos), y desapareció casi completamente en los potreros, donde los individuos estuvieron agregados en las pocas áreas anegadas. En los potreros, los individuos de M. coffeus estuvieron agrupados en los árboles remanentes debido a su hábito arborícola y su condición de pulmonado. Se sugiere que la escasez de los gasterópodos está relacionada con la degradación del microhábitat físico, y la alteración de propiedades del suelo. Finalmente, también planteamos que la extinción local de N. virginea debida a la tala puede ejercer fuertes efectos negativos sobre la función ecosistémica debido a que es un omnívoro dominante.


Assuntos
Animais , Ecossistema , Gastrópodes , Rhizophoraceae , Colômbia , Gastrópodes/anatomia & histologia , Gastrópodes/fisiologia , Densidade Demográfica , Dinâmica Populacional , Rios
18.
J Virol ; 86(3): 1832-43, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22090136

RESUMO

Respiratory syncytial virus (RSV) is one of the major causes of respiratory infections in children, and it is the main pathogen causing bronchiolitis in infants. The binding and entry mechanism by which RSV infects respiratory epithelial cells has not yet been determined. In this study, the earliest stages of RSV infection in normal human bronchial epithelial cells were probed by tracking virions with fluorescent lipophilic dyes in their membranes. Virions colocalized with cholesterol-containing plasma membrane microdomains, identified by their ability to bind cholera toxin subunit B. Consistent with an important role for cholesterol in RSV infection, cholesterol depletion profoundly inhibited RSV infection, while cholesterol repletion reversed this inhibition. Merger of the outer leaflets of the viral envelope and the cell membrane appeared to be triggered at these sites. Using small-molecule inhibitors, RSV infection was found to be sensitive to Pak1 inhibition, suggesting the requirement of a subsequent step of cytoskeletal reorganization that could involve plasma membrane rearrangements or endocytosis. It appears that RSV entry depends on its ability to dock to cholesterol-rich microdomains (lipid rafts) in the plasma membrane where hemifusion events begin, assisted by a Pak1-dependent process.


Assuntos
Brônquios/metabolismo , Colesterol/metabolismo , Fusão de Membrana , Vírus Sinciciais Respiratórios/fisiologia , Brônquios/citologia , Linhagem Celular , Células Epiteliais/metabolismo , Citometria de Fluxo , Corantes Fluorescentes , Humanos
19.
Infectio ; 15(2): 84-91, abr.-jun. 2011. ilus, tab
Artigo em Espanhol | LILACS, COLNAL | ID: lil-635678

RESUMO

Objetivos. Evaluar y determinar el punto de corte para la detección de IgM anti-Toxoplasma por el método ELISA, en muestras de sangre de cordónumbilical, mediante dos ensayos comerciales diferentes, y correlacionar los resultados obtenidos con el diagnóstico de toxoplasmosis congénitarealizado por seguimiento serológico y los datos clínicos. Métodos. Se evaluó la prueba IgM anti-Toxoplasma ELISA de Vircell®, frente a los resultados por Western blot e IgM ELISA de Labsystems®. Seestudiaron 105 muestras de cordón umbilical de niños colombianos, obtenidas de seis ciudades diferentes por Western blot y seguimiento clínico yserológico en aquellos positivos. Se obtuvo una curva receptor-operador (ROC) para la prueba ELISA IgM anti-Toxoplasma de Vircell® y de Labsystems®. Se analizó la concordancia entre pruebas en 105 sueros obtenidos de cordón umbilical. Resultados. El mejor desempeño para la prueba Vircell® fue con un punto de corte de índice 8 y la prueba de Labsystems® con un punto de cortede 16 inmunounidades enzimáticas. Frente al Western blot, la prueba Vircell® tuvo una sensibilidad de 100 % (IC 95%; 71,8-100) y una especificidadde 78 % (IC 95%; 69-85,7), la prueba Labsystems® tuvo una sensibilidad de 100 % (IC95%; 71,8-100) y una especificidad de 100 % (IC95%; 96-100). Laconcordancia entre ambas pruebas (Labsystems® y Vircell®) fue de 80 %, con un índice kappa de 0,45. Conclusiones. Un punto de corte de un índice 8 para la prueba ELISA IgM anti-Toxoplasma de Vircell® y un punto de corte de 16 inmunounidadesenzimáticas por Labsystems®, permiten identificar infecciones congénitas en sangre de cordón umbilical en niños colombianos.


Objectives: To evaluate and validate the detection of anti-Toxoplasma IgM ELISA in umbilical cord blood by means of two different commercialassays and to correlate the results with the diagnosis of congenital infection in children by serological follow up and clinical data. Materials and methods: We evaluated the commercial anti-Toxoplasma IgM ELISA kitÔ from Vircell (Granada, Spain) compared to the results of Toxoplasma IgM Western blotÔ (LDbio, Lyon, France) and IgM ELISA testÔ from Labsystems (Finland). We obtained the receptor-operator curve (ROC) for the IgMELISA assay form Vircell and Labsystems. We studied 105 umbilical cord blood serum samples from Colombian children from six different cities by Westernblot, and clinical and serological follow up for positive cases. The kappa agreement index was determined for the 105 sera obtained from umbilical cords. Results: The Vircell assay showed a better performance with a cut-off index of 8 against a 16 for Labsystems for enzyme immunounits (EUI). Whenthe results were evaluated against the Western blot assay, the Vircell IgM assay had a sensitivity of 100% (IC95%: 71.8-100) and a specificity of 78%(IC95%: 69-85.7), the IgM assay from Labsystems had a sensitivity of 100% (IC95%; 71.8-100) and a specificity of 100% (IC95%; 96-100). Agreement between both tests (Labsystems and Vircell) was 80% and had a kappa index of 0.45. Conclusions: A cut-off point of 8 for the anti-Toxoplasma IgM ELISA assay from Vircell and 16 EIU for the Labsystems assay allow the identificationof congenital infections in umbilical cord blood samples from Colombian children.


Assuntos
Humanos , Masculino , Feminino , Gravidez , Recém-Nascido , Ensaio de Imunoadsorção Enzimática , Toxoplasmose , Recém-Nascido , Triagem Neonatal , Assistência ao Convalescente , Infecções
20.
PLoS One ; 6(2): e16722, 2011 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-21386905

RESUMO

BACKGROUND: Age-related macular degeneration (AMD) is the leading cause of legal blindness in the elderly population. Debris (termed drusen) below the retinal pigment epithelium (RPE) have been recognized as a risk factor for dry AMD and its progression to wet AMD, which is characterized by choroidal neovascularization (CNV). The underlying mechanism of how drusen might elicit CNV remains undefined. Cigarette smoking, oxidative damage to the RPE and inflammation are postulated to be involved in the pathophysiology of the disease. To better understand the cellular mechanism(s) linking oxidative stress and inflammation to AMD, we examined the expression of pro-inflammatory monocyte chemoattractant protein-1 (MCP-1), pro-angiogenic vascular endothelial growth factor (VEGF) and anti-angiogenic pigment epithelial derived factor (PEDF) in RPE from smoker patients with AMD. We also evaluated the effects of hydroquinone (HQ), a major pro-oxidant in cigarette smoke on MCP-1, VEGF and PEDF expression in cultured ARPE-19 cells and RPE/choroids from C57BL/6 mice. PRINCIPAL FINDINGS: MCP-1, VEGF and PEDF expression was examined by real-time PCR, Western blot, and ELISA. Low levels of MCP-1 protein were detected in RPE from AMD smoker patients relative to controls. Both MCP-1 mRNA and protein were downregulated in ARPE-19 cells and RPE/choroids from C57BL/6 mice after 5 days and 3 weeks of exposure to HQ-induced oxidative injury. VEGF protein expression was increased and PEDF protein expression was decreased in RPE from smoker patients with AMD versus controls resulting in increased VEGF/PEDF ratio. Treatment with HQ for 5 days and 3 weeks increased the VEGF/PEDF ratio in vitro and in vivo. CONCLUSION: We propose that impaired RPE-derived MCP-1-mediated scavenging macrophages recruitment and phagocytosis might lead to incomplete clearance of proinflammatory debris and infiltration of proangiogenic macrophages which along with increased VEGF/PEDF ratio favoring angiogenesis might promote drusen accumulation and progression to CNV in smoker patients with dry AMD.


Assuntos
Hidroquinonas/efeitos adversos , Epitélio Pigmentado da Retina/efeitos dos fármacos , Epitélio Pigmentado da Retina/metabolismo , Fumaça/efeitos adversos , Idoso , Idoso de 80 Anos ou mais , Animais , Células Cultivadas , Quimiocina CCL2/genética , Quimiocina CCL2/metabolismo , Neovascularização de Coroide/genética , Neovascularização de Coroide/metabolismo , Neovascularização de Coroide/patologia , Proteínas do Olho/genética , Proteínas do Olho/metabolismo , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Hidroquinonas/isolamento & purificação , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Fatores de Crescimento Neural/genética , Fatores de Crescimento Neural/metabolismo , Epitélio Pigmentado da Retina/patologia , Serpinas/genética , Serpinas/metabolismo , Fumar/efeitos adversos , Fumar/patologia , Nicotiana/química , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo
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