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1.
Braz J Med Biol Res ; 54(11): e9941, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34495252

RESUMO

Acute kidney injury (AKI) is a common complication in seriously ill patients, while renal ischemia-reperfusion (I/R) injury is the most frequent event in this oxidative renal injury. N-acetylcysteine (NAC) is a small molecule containing a thiol group that has antioxidant properties, promoting detoxification and acting directly as a free radical scavenger. In this study, the protective effect of NAC was investigated in short-term (30 min) and long-term (45 min) ischemic AKI. This was achieved via clamping of the renal artery for 30 or 45 min in Wistar rats to induce I/R injury. AKI worsened with a longer period of ischemia (45 compared to 30 min) due to probable irreversible damage. Preconditioning with NAC in short-term ischemia improved renal blood flow and increased creatinine clearance by reducing oxidative metabolites and increasing antioxidant capacity. Otherwise, NAC did not change these parameters in the long-term ischemia. Therefore, this study demonstrated that the period of ischemia determines the severity of the AKI, and NAC presented antioxidant effects in short-term ischemia but not in long-term ischemia, confirming that there is a possible therapeutic window for its renoprotective effect.


Assuntos
Injúria Renal Aguda , Traumatismo por Reperfusão , Acetilcisteína/uso terapêutico , Injúria Renal Aguda/prevenção & controle , Animais , Humanos , Rim , Estresse Oxidativo , Ratos , Ratos Wistar , Traumatismo por Reperfusão/prevenção & controle
2.
Mucosal Immunol ; 11(1): 236-248, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28513595

RESUMO

The mechanisms that enable preservation of gut mucosal integrity during persistent viral replication and inherent inflammation remain unclear. Here, we investigated, for the first time, gut homeostasis in HIV-2 infection, a naturally occurring form of attenuated HIV disease. We found viral replication in both sigmoid and ileum of asymptomatic HIV-2+ patients (range: 240-851 circulating CD4+T-cells per µl) despite their undetectable viremia, accompanied by interferon-γ-producing CD8 T-cell expansion, irrespective of antiretroviral treatment. Nevertheless, there was no CD4 T-cell depletion, and Foxp3+ and IL-17- or IL-22-producing CD4 T-cell numbers were unaffected. Moreover, IL-22-producing innate lymphoid cells and IL-22-induced antimicrobial peptides and mucins were maintained. In agreement, the epithelium histology was preserved, including tight junction protein zonula occludens (ZO-1) levels. Furthermore, in vitro infection of colon epithelia with primary isolates revealed no HIV-2 impact on ZO-1 expression. Notably, sigmoid transcriptional levels of CCL20 and CCL28 were significantly increased, in direct correlation with GM-CSF, indicating a local response able to enhance CD4 T-cell recruitment. In conclusion, maintenance of mucosal integrity in HIV-2 infection was associated with T-cell recruitment responses, potentially counteracting CD4 T-cell depletion due to HIV-2 replication. These data have unique implications for the design of therapies targeting gut homeostasis in HIV-1 infection and other chronic inflammatory settings.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Colo/imunologia , Infecções por HIV/imunologia , HIV-2/imunologia , Mucosa Intestinal/imunologia , Intestinos/imunologia , Idoso , Doenças Assintomáticas , Células Cultivadas , Feminino , Homeostase , Humanos , Memória Imunológica , Interleucinas/metabolismo , Mucosa Intestinal/patologia , Mucosa Intestinal/virologia , Intestinos/microbiologia , Intestinos/virologia , Masculino , Pessoa de Meia-Idade , Replicação Viral , Interleucina 22
3.
Leukemia ; 31(10): 2075-2084, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28111464

RESUMO

Although the BTK inhibitor ibrutinib has transformed the management of patients with chronic lymphocytic leukemia (CLL), it does not induce substantial apoptosis in vitro, and as such the mechanisms underlying its ability to kill CLL cells are not well understood. Acalabrutinib, a more specific BTK inhibitor now in development, also appears to be highly effective in CLL, but the connection of its mechanism with CLL cell death is also unclear. Using dynamic BH3 profiling, we analyzed alterations in the function of the mitochondrial apoptotic pathway induced by ibrutinib and acalabrutinib. We studied CLL patient samples treated ex vivo with both drugs, as well as primary samples from CLL patients on clinical trials of both drugs. We found that BTK inhibition enhances mitochondrial BCL-2 dependence without significantly altering overall mitochondrial priming. Enhancement of BCL-2 dependence was accompanied by an increase in the pro-apoptotic protein BIM. In contrast, treatment with the selective BCL-2 inhibitor venetoclax enhanced overall mitochondrial priming without increasing BCL-2 dependence. Pre-treatment of CLL cells with either BTK inhibitor, whether ex vivo or in vivo in patients, enhanced killing by venetoclax. Our data suggest that BTK inhibition enhances mitochondrial BCL-2 dependence, supporting the ongoing development of clinical trials combining BTK and BCL-2 inhibition.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Benzamidas/farmacologia , Compostos Bicíclicos Heterocíclicos com Pontes/agonistas , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Terapia de Alvo Molecular , Proteínas de Neoplasias/antagonistas & inibidores , Inibidores de Proteínas Quinases/farmacologia , Proteínas Tirosina Quinases/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-bcl-2/fisiologia , Pirazinas/farmacologia , Pirazóis/farmacologia , Pirimidinas/farmacologia , Sulfonamidas/agonistas , Adenina/análogos & derivados , Tirosina Quinase da Agamaglobulinemia , Apoptose/efeitos dos fármacos , Proteína 11 Semelhante a Bcl-2/biossíntese , Proteína 11 Semelhante a Bcl-2/genética , Benzamidas/administração & dosagem , Benzamidas/uso terapêutico , Compostos Bicíclicos Heterocíclicos com Pontes/administração & dosagem , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Compostos Bicíclicos Heterocíclicos com Pontes/uso terapêutico , Ensaios Clínicos como Assunto , Ensaios de Seleção de Medicamentos Antitumorais , Sinergismo Farmacológico , Humanos , Leucemia Linfocítica Crônica de Células B/patologia , Mitocôndrias/efeitos dos fármacos , Proteínas de Neoplasias/fisiologia , Fragmentos de Peptídeos , Piperidinas , Inibidores de Proteínas Quinases/administração & dosagem , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Proto-Oncogênicas , Pirazinas/administração & dosagem , Pirazinas/uso terapêutico , Pirazóis/administração & dosagem , Pirazóis/uso terapêutico , Pirimidinas/administração & dosagem , Pirimidinas/uso terapêutico , Sulfonamidas/administração & dosagem , Sulfonamidas/farmacologia , Sulfonamidas/uso terapêutico
4.
Braz J Med Biol Res ; 51(2): e6373, 2017 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-29267497

RESUMO

Cyclosporin-A (CsA) is an immunosuppressant associated with acute kidney injury and chronic kidney disease. Nephrotoxicity associated with CsA involves the increase in afferent and efferent arteriole resistance, decreased renal blood flow (RBF) and glomerular filtration. The aim of this study was to evaluate the effect of Endothelin-1 (ET-1) receptor blockade with bosentan (BOS) and macitentan (MAC) antagonists on altered renal function induced by CsA in normotensive and hypertensive animals. Wistar and genetically hypertensive rats (SHR) were separated into control group, CsA group that received intraperitoneal injections of CsA (40 mg/kg) for 15 days, CsA+BOS and CsA+MAC that received CsA and BOS (5 mg/kg) or MAC (25 mg/kg) by gavage for 15 days. Plasma creatinine and urea, mean arterial pressure (MAP), RBF and renal vascular resistance (RVR), and immunohistochemistry for ET-1 in the kidney cortex were measured. CsA decreased renal function, as shown by increased creatinine and urea. There was a decrease in RBF and an increase in MAP and RVR in normotensive and hypertensive animals. These effects were partially reversed by ET-1 antagonists, especially in SHR where increased ET-1 production was observed in the kidney. Most MAC effects were similar to BOS, but BOS seemed to be better at reversing cyclosporine-induced changes in renal function in hypertensive animals. The results of this work suggested the direct participation of ET-1 in renal hemodynamics changes induced by cyclosporin in normotensive and hypertensive rats. The antagonists of ET-1 MAC and BOS reversed part of these effects.


Assuntos
Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/prevenção & controle , Ciclosporina/toxicidade , Antagonistas do Receptor de Endotelina A/farmacologia , Imunossupressores/toxicidade , Pirimidinas/farmacologia , Sulfonamidas/farmacologia , Injúria Renal Aguda/fisiopatologia , Animais , Bosentana , Creatinina/sangue , Antagonistas do Receptor de Endotelina A/uso terapêutico , Hemodinâmica , Immunoblotting , Imuno-Histoquímica , Rim/efeitos dos fármacos , Rim/fisiopatologia , Masculino , Estresse Oxidativo/fisiologia , Substâncias Protetoras/farmacologia , Substâncias Protetoras/uso terapêutico , Pirimidinas/uso terapêutico , Ratos Endogâmicos SHR , Ratos Wistar , Reprodutibilidade dos Testes , Sulfonamidas/uso terapêutico , Resultado do Tratamento , Ureia/sangue
5.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;54(11): e9941, 2021. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1339454

RESUMO

Acute kidney injury (AKI) is a common complication in seriously ill patients, while renal ischemia-reperfusion (I/R) injury is the most frequent event in this oxidative renal injury. N-acetylcysteine (NAC) is a small molecule containing a thiol group that has antioxidant properties, promoting detoxification and acting directly as a free radical scavenger. In this study, the protective effect of NAC was investigated in short-term (30 min) and long-term (45 min) ischemic AKI. This was achieved via clamping of the renal artery for 30 or 45 min in Wistar rats to induce I/R injury. AKI worsened with a longer period of ischemia (45 compared to 30 min) due to probable irreversible damage. Preconditioning with NAC in short-term ischemia improved renal blood flow and increased creatinine clearance by reducing oxidative metabolites and increasing antioxidant capacity. Otherwise, NAC did not change these parameters in the long-term ischemia. Therefore, this study demonstrated that the period of ischemia determines the severity of the AKI, and NAC presented antioxidant effects in short-term ischemia but not in long-term ischemia, confirming that there is a possible therapeutic window for its renoprotective effect.


Assuntos
Humanos , Animais , Ratos , Traumatismo por Reperfusão/prevenção & controle , Injúria Renal Aguda/prevenção & controle , Acetilcisteína/uso terapêutico , Ratos Wistar , Estresse Oxidativo , Rim
6.
Leukemia ; 30(1): 173-81, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26165234

RESUMO

Bruton's tyrosine kinase (BTK) kinase is a member of the TEC kinase family and is a key regulator of the B-cell receptor (BCR)-mediated signaling pathway. It is important for B-cell maturation, proliferation, survival and metastasis. Pharmacological inhibition of BTK is clinically effective against a variety of B-cell malignances, such as mantle cell lymphoma, chronic lymphocytic leukemia (CLL), acute myeloid leukemia (AML) and activated B-cell-diffuse large B-cell lymphoma. MNK kinase is one of the key downstream regulators in the RAF-MEK-ERK signaling pathway and controls protein synthesis via regulating the activity of eIF4E. Inhibition of MNK activity has been observed to moderately inhibit the proliferation of AML cells. Through a structure-based drug-design approach, we have discovered a selective and potent BTK/MNK dual kinase inhibitor (QL-X-138), which exhibits covalent binding to BTK and noncovalent binding to MNK. Compared with the BTK kinase inhibitor (PCI-32765) and the MNK kinase inhibitor (cercosporamide), QL-X-138 enhanced the antiproliferative efficacies in vitro against a variety of B-cell cancer cell lines, as well as AML and CLL primary patient cells, which respond moderately to BTK inhibitor in vitro. The agent can effectively arrest the growth of lymphoma and leukemia cells at the G0-G1 stage and can induce strong apoptotic cell death. These primary results demonstrate that simultaneous inhibition of BTK and MNK kinase activity might be a new therapeutic strategy for B-cell malignances.


Assuntos
Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Leucemia/tratamento farmacológico , Linfoma/tratamento farmacológico , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Tirosina Quinases/antagonistas & inibidores , Tirosina Quinase da Agamaglobulinemia , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Desenho de Fármacos , Humanos , Leucemia/patologia , Linfoma/patologia
7.
Nat Commun ; 6: 8866, 2015 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-26638776

RESUMO

Patients with chromosome 13q deletion or normal cytogenetics represent the majority of chronic lymphocytic leukaemia (CLL) cases, yet have relatively few driver mutations. To better understand their genomic landscape, here we perform whole-genome sequencing on a cohort of patients enriched with these cytogenetic characteristics. Mutations in known CLL drivers are seen in only 33% of this cohort, and associated with normal cytogenetics and unmutated IGHV. The most commonly mutated gene in our cohort, IGLL5, shows a mutational pattern suggestive of activation-induced cytidine deaminase (AID) activity. Unsupervised analysis of mutational signatures demonstrates the activities of canonical AID (c-AID), leading to clustered mutations near active transcriptional start sites; non-canonical AID (nc-AID), leading to genome-wide non-clustered mutations, and an ageing signature responsible for most mutations. Using mutation clonality to infer time of onset, we find that while ageing and c-AID activities are ongoing, nc-AID-associated mutations likely occur earlier in tumour evolution.


Assuntos
Citidina Desaminase/genética , Leucemia Linfocítica Crônica de Células B/enzimologia , Envelhecimento/genética , Evolução Biológica , Estudos de Coortes , Citidina Desaminase/metabolismo , Genoma Humano , Estudo de Associação Genômica Ampla , Humanos , Leucemia Linfocítica Crônica de Células B/genética , Mutação
8.
J AOAC Int ; 81(3): 645-7, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9606926

RESUMO

A flow injection system for determination of copper in beer by atomic absorption spectrophotometry by the standard additions method is described. The manifold, based on the merging zone technique, prevents the burner head from clogging, as observed with the conventional reference method. With 5 standard additions, results are comparable with those of the reference method. Relative deviations were less than 5.8%, precision was better than 6.4%, and sampling rate was about 30 samples/ h. A less precise, less accurate, but faster procedure (75 samples/h) is possible with only 2 standard additions. The detection limit was 5 micrograms/L.


Assuntos
Cerveja/análise , Cobre/análise , Análise de Injeção de Fluxo/métodos , Espectrofotometria Atômica/métodos , Padrões de Referência
9.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;51(2): e6373, 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-889016

RESUMO

Cyclosporin-A (CsA) is an immunosuppressant associated with acute kidney injury and chronic kidney disease. Nephrotoxicity associated with CsA involves the increase in afferent and efferent arteriole resistance, decreased renal blood flow (RBF) and glomerular filtration. The aim of this study was to evaluate the effect of Endothelin-1 (ET-1) receptor blockade with bosentan (BOS) and macitentan (MAC) antagonists on altered renal function induced by CsA in normotensive and hypertensive animals. Wistar and genetically hypertensive rats (SHR) were separated into control group, CsA group that received intraperitoneal injections of CsA (40 mg/kg) for 15 days, CsA+BOS and CsA+MAC that received CsA and BOS (5 mg/kg) or MAC (25 mg/kg) by gavage for 15 days. Plasma creatinine and urea, mean arterial pressure (MAP), RBF and renal vascular resistance (RVR), and immunohistochemistry for ET-1 in the kidney cortex were measured. CsA decreased renal function, as shown by increased creatinine and urea. There was a decrease in RBF and an increase in MAP and RVR in normotensive and hypertensive animals. These effects were partially reversed by ET-1 antagonists, especially in SHR where increased ET-1 production was observed in the kidney. Most MAC effects were similar to BOS, but BOS seemed to be better at reversing cyclosporine-induced changes in renal function in hypertensive animals. The results of this work suggested the direct participation of ET-1 in renal hemodynamics changes induced by cyclosporin in normotensive and hypertensive rats. The antagonists of ET-1 MAC and BOS reversed part of these effects.


Assuntos
Animais , Masculino , Pirimidinas/farmacologia , Ciclosporina/toxicidade , Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/prevenção & controle , Antagonistas dos Receptores de Endotelina/farmacologia , Imunossupressores/toxicidade , Ureia/sangue , Imuno-Histoquímica , Immunoblotting , Reprodutibilidade dos Testes , Ratos Wistar , Creatinina/sangue , Injúria Renal Aguda/fisiopatologia , Antagonistas dos Receptores de Endotelina/uso terapêutico , Bosentana , Hemodinâmica , Rim/efeitos dos fármacos
13.
Fresenius J Anal Chem ; 366(1): 112-5, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11225806

RESUMO

A flow injection system for the automatic determination of total phosphorus in beer is described. The developed manifold uses a two-stage photooxidation/thermal digestion procedure together with oxidizing and hydrolyzing reagents to convert all forms of phosphorus compounds to orthophosphate. Polyphosphates are hydrolyzed by acid and heat, and organo-phosphates are digested by UV-catalyzed peroxodisulfate oxidation. The orthophosphate formed is then spectrophotometrically determined by the phosphomolybdenum blue reaction, using stannous chloride as reducing agent. The results obtained for a set of 19 beer samples (with concentrations from 120 to 735 mg P/L) were in good agreement with the reference method, the maximum relative deviation found being 4.7%. Relative standard deviations for ten consecutive determinations were lower than 1.5%, and a detection limit of 1 mg P/L was achieved.


Assuntos
Cerveja/análise , Análise de Injeção de Fluxo , Fósforo/análise , Espectrofotometria/métodos , Temperatura Alta , Oxirredução , Controle de Qualidade , Sensibilidade e Especificidade , Compostos de Estanho , Raios Ultravioleta
14.
Braz. j. phys. ther. (Impr.) ; 12(6)Nov.-Dec. 2008. graf, tab
Artigo em Inglês, Português | LILACS | ID: lil-504891

RESUMO

OBJETIVO: Avaliar a modificação na quantidade de carga transportada, o modelo e o modo de transportar mochilas escolares após sessões educativas. MÉTODOS: Estudo de uma série de casos, com 99 crianças de sete a 11 anos do ensino fundamental, em escola particular da cidade São Paulo, São Paulo. Foram avaliadas a massa corporal (kg) e estatura dos alunos (cm), quantidade de carga transportada nas mochilas (kg). Os modelos e os modos de transporte das mochilas foram avaliados por filmagem pré e pós-intervenção. Como medida de intervenção, os sujeitos (crianças, pais e professores) foram submetidos a uma sessão educativa, que consistiu de orientações teóricas sobre coluna vertebral e transporte de carga. Para os escolares foi adicionada orientação prática das posturas corretas no transporte de carga. Os escolares receberam um reforço prático mensal por três meses. Pais e professores receberam reforço em folheto informativo e orientações na homepage da escola. Os dados foram analisados pelos testes estatísticos de igualdade de duas proporções e Wilcoxon. O nível de significância adotado foi 5 por cento. RESULTADOS: O modelo de mochila modificou para duas alças de 46,5 por cento para 60,6 por cento (p=0,046), modo de transporte para ombro bilateral de 41,4 por cento para 55,6 por cento (p=0,047). A carga transportada nas mochilas diminuiu 2,66kg (p<0,001) e a relação massa corporal do sujeito e carga transportada nas mochilas diminuiu 7 por cento. Na modificação por categorias, o número de alunos do grupo inadequado (carga transportada>15 por cento da massa corporal do aluno) diminuiu (p<0,001). CONCLUSÕES: As sessões educativas promoveram mudanças na utilização de mochilas, revelando adesão satisfatória ao modelo de intervenção proposto entre os escolares e o importante papel da Fisioterapia na saúde escolar.


OBJECTIVE: To evaluate the changes in loads carried, in the model of backpack used and in the way of carrying school backpacks after the implementation of an educational program. METHODS: This study was performed on 99 children aged seven to 11 years at elementary school level in a private school in São Paulo, São Paulo, Brazil. The subjects' body mass (kg) and height (cm) and the loads carried in their backpacks (kg) were evaluated. The backpack models and the ways of carrying them were evaluated by filming before and after the intervention. The intervention program consisted of educational sessions offered to the children, parents and teachers. The sessions involved lectures about the spine and about the principles of load carrying. The children also received practical guidance relating to correct postures for load carrying. The children received monthly practical reinforcement for three months. The parents and teachers received reinforcement by means of information flyers and guidance on the school's home page. The data were analyzed by means of two-proportion equality and Wilcoxon statistical tests. The significance level was considered as α=0.05. RESULTS: The use of a two-strap backpack model increased from 46.5 percent to 60.6 percent (p=0.046) and carrying it on two shoulders increased from 41.4 percent to 55.6 percent (p=0.047). The load carried in the backpacks decreased by 2.66kg (p<0.001) and the ratio between the subject's body mass and the load carried in the backpacks decreased by 7 percent. With regard to change per category, the number of subjects in the inappropriate group (load carried>15 percent of the subject's body mass) decreased (p<0.001). CONCLUSIONS: The educational sessions promoted changes in backpack use and it was observed a satisfactory adherence to the intervention program proposed. These results demonstrate the importance of Physical Therapy educational programs in schoolchildren's health.

15.
Neurobiologia ; 47(1): 33-8, 1984.
Artigo em Português | LILACS | ID: lil-24070

RESUMO

Os autores apresentam 4 casos de sindrome de Kluver Bucy parcial e completa comentam sobre o quadro clinico, a etiologia e associacao com atrofia de lobos temporais.Chamam atencao sobre a possibilidade de ocorrer casos cujo diagnostico passaria desapercebido


Assuntos
Lactente , Pré-Escolar , Criança , Humanos , Masculino , Feminino , Comportamento , Psicocirurgia , Lobo Temporal
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