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1.
Biochimie ; 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39089640

RESUMO

Snakebite envenomations result in acute and chronic physical and psychological health effects on their victims, leading to a substantial socio-economic burden in tropical and subtropical countries. Local necrosis is one of the serious effects caused by envenomation, primarily induced by snake venoms from the Viperidae family through the direct action of components collectively denominated as myotoxins, including the phopholipase A2-like (PLA2-like) toxins. Considering the limitations of antivenoms in preventing the rapid development of local tissue damage caused by envenomation, the use of small molecule therapeutics has been suggested as potential first-aid treatments or as adjuvants to antivenom therapy. In this review, we provide an overview of the structural interactions of molecules exhibiting inhibitory activity toward PLA2-like toxins. Additionally, we discuss the implications for the myotoxic mechanism of PLA2-like toxins and the molecules involved in their activation, highlighting key differences between activators and inhibitors. Finally, we integrate all these results to propose a classification of inhibitors into three different classes and five sub-classes. Taking into account the structural and affinity information, we compare the different inhibitors/ligands to gain a deeper understanding of the structural basis for the effective inhibition of PLA2-like toxins. By offering these insights, we aim to contribute to the search for new and efficient inhibitor molecules to complement and improve current therapy by conventional antivenoms.

2.
Pathogens ; 13(2)2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38392842

RESUMO

Protein synthesis has been a very rich target for developing drugs to control prokaryotic and eukaryotic pathogens. Despite the development of new drug formulations, treating human cutaneous and visceral Leishmaniasis still needs significant improvements due to the considerable side effects and low adherence associated with the current treatment regimen. In this work, we show that the di-substituted urea-derived compounds I-17 and 3m are effective in inhibiting the promastigote growth of different Leishmania species and reducing the macrophage intracellular load of amastigotes of the Leishmania (L.) amazonensis and L. major species, in addition to exhibiting low macrophage cytotoxicity. We also show a potential immunomodulatory effect of I-17 and 3m in infected macrophages, which exhibited increased expression of inducible Nitric Oxide Synthase (NOS2) and production of Nitric Oxide (NO). Our data indicate that I-17, 3m, and their analogs may be helpful in developing new drugs for treating leishmaniasis.

3.
Arq. bras. oftalmol ; Arq. bras. oftalmol;87(2): e2023, 2024. tab
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1533796

RESUMO

ABSTRACT Purpose: To investigate the clinical benefits of the co-application of bevacizumab and tissue plasminogen activator as adjuncts in the surgical treatment of proliferative diabetic retinopathy. Methods: Patients who underwent vitrectomy for proliferative dia-betic retinopathy complications were preoperatively given in-travitreal injection with either bevacizumab and tissue plasminogen activator (Group 1) or bevacizumab alone (Group 2). Primary outcomes were surgery time and number of intraoperative iatrogenic retinal breaks. Secondary outcomes included changes in the best-corrected visual acuity and postoperative complications at 3 months postoperatively. Results: The mean surgery time in Group 1 (52.95 ± 5.90 min) was significantly shorter than that in Group 2 (79.61 ± 12.63 min) (p<0.001). The mean number of iatrogenic retinal breaks was 0.50 ± 0.59 (0-2) in Group 1 and 2.00 ± 0.83 (0-3) in Group 2 (p<0.001). The best-corrected visual acuity significantly improved in both groups (p<0.001). One eye in each group developed retinal detachment. Conclusion: Preoperative co-application of bevacizumab and tissue plasminogen activator as adjuncts in the surgical treatment of proliferative diabetic retinopathy shortens the surgery time and reduces the number of intraoperative iatrogenic retinal breaks.

4.
Nutr Neurosci ; 26(1): 72-84, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36625764

RESUMO

Although the pathogenesis of Parkinson's Disease (PD) is not completely understood, there is a consensus that it can be caused by multifactorial mechanisms involving genetic susceptibility, epigenetic modifications induced by toxins and mitochondrial dysfunction. In the past 20 years, great efforts have been made in order to clarify molecular mechanisms that are risk factors for this disease, as well as to identify bioactive agents for prevention and slowing down of its progression. Nutraceutical products have received substantial interest due to their nutritional, safe and therapeutic effects on several chronic diseases. The aim of this review was to gather the main evidence of the epigenetic mechanisms involved in the neuroprotective effects of phenolic compounds currently under investigation for the treatment of toxin-induced PD. These studies confirm that the neuroprotective actions of polyphenols involve complex epigenetic modulations, demonstrating that the intake of these natural compounds can be a promising, low-cost, pharmacogenomic strategy against the development of PD.


Assuntos
Doença de Parkinson , Humanos , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/genética , Doença de Parkinson/prevenção & controle , Polifenóis/farmacologia , Nutrigenômica , Epigênese Genética , Predisposição Genética para Doença
5.
Handb Exp Pharmacol ; 2022 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-35768554

RESUMO

Various human tissues express the calcium-activated chloride channel Anoctamin 1 (ANO1), also known as TMEM16A. ANO1 allows the passive chloride flux that controls different physiological functions ranging from muscle contraction, fluid and hormone secretion, gastrointestinal motility, and electrical excitability. Overexpression of ANO1 is associated with pathological conditions such as hypertension and cancer. The molecular cloning of ANO1 has led to a surge in structural, functional, and physiological studies of the channel in several tissues. ANO1 is a homodimer channel harboring two pores - one in each monomer - that work independently. Each pore is activated by voltage-dependent binding of two intracellular calcium ions to a high-affinity-binding site. In addition, the binding of phosphatidylinositol 4,5-bisphosphate to sites scattered throughout the cytosolic side of the protein aids the calcium activation process. Furthermore, many pharmacological studies have established ANO1 as a target of promising compounds that could treat several illnesses. This chapter describes our current understanding of the physiological roles of ANO1 and its regulation under physiological conditions as well as new pharmacological compounds with potential therapeutic applications.

6.
Cell Stress Chaperones ; 27(4): 417-429, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35687225

RESUMO

Indigo is a bis-indolic alkaloid that has antioxidant and anti-inflammatory effects reported in literature and is a promissory compound for treating chronic inflammatory diseases. This fact prompted to investigate the effects of this alkaloid in the experimental model of Duchenne muscular dystrophy. The main aim of this study was to evaluate the potential role of the indigo on oxidative stress and related signaling pathways in primary skeletal muscle cell cultures and in the diaphragm muscle from mdx mice. The MTT and Neutral Red assays showed no indigo dose-dependent toxicities in mdx muscle cells at concentrations analyzed (3.12, 6.25, 12.50, and 25.00 µg/mL). Antioxidant effect of indigo, in mdx muscle cells and diaphragm muscle, was demonstrated by reduction in 4-HNE content, H2O2 levels, DHE reaction, and lipofuscin granules. A significant decrease in the inflammatory process was identified by a reduction on TNF and NF-κB levels, on inflammatory area, and on macrophage infiltration in the dystrophic sample, after indigo treatment. Upregulation of PGC-1α and SIRT1 in dystrophic muscle cells treated with indigo was also observed. These results suggest the potential of indigo as a therapeutic agent for muscular dystrophy, through their action anti-inflammatory, antioxidant, and modulator of SIRT1/PGC-1α pathway.


Assuntos
Distrofia Muscular de Duchenne , Animais , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Antioxidantes/metabolismo , Modelos Animais de Doenças , Peróxido de Hidrogênio/metabolismo , Índigo Carmim/metabolismo , Índigo Carmim/farmacologia , Índigo Carmim/uso terapêutico , Alcaloides Indólicos/metabolismo , Alcaloides Indólicos/farmacologia , Alcaloides Indólicos/uso terapêutico , Camundongos , Camundongos Endogâmicos mdx , Modelos Teóricos , Músculo Esquelético/metabolismo , Distrofia Muscular de Duchenne/tratamento farmacológico , Transdução de Sinais , Sirtuína 1/metabolismo
8.
J Clin Endocrinol Metab ; 107(5): 1216-1224, 2022 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-34888679

RESUMO

Primary hyperlipidemias include a heterogeneous set of monogenic and polygenic conditions characterized by a strong family aggregation, severe forms of hypercholesterolemia and/or hypertriglyceridemia, appearance early on life, and a high risk of cardiovascular events and/or recurrent pancreatitis. In real life, a small proportion of the primary hyperlipidemia cases is recognized and treated properly. Our goal is to present an update of current and upcoming therapies for patients with primary hyperlipidemia. Recently, new lipid-lowering medications have obtained authorization from the U.S. Food and Drug Administration and the European Medicines Agency. These drugs target metabolic pathways, including (adenosine 5'-triphosphates)-citrate lyase (bempedoic acid), proprotein convertase subtilisin/kexin 9 (inclisiran), apolipoprotein CIII (volanesorsen), and angiopoietin-like 3 (volanesorsen), that have additive effects with the actions of the currently available therapies (i.e., statins, ezetimibe or fibrates). We discuss the potential clinical indications for the novel medications. To conclude, the addition of these new medications to the therapeutic options for primary hyperlipidemia patients may increase the likelihood of achieving the treatment targets. Also, it could be a safer alternative for patients with side effects for the currently available drugs.


Assuntos
Anticolesterolemiantes , Inibidores de Hidroximetilglutaril-CoA Redutases , Hipercolesterolemia , Hiperlipidemias , Hipertrigliceridemia , Anticolesterolemiantes/uso terapêutico , LDL-Colesterol , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Hipercolesterolemia/tratamento farmacológico , Hiperlipidemias/tratamento farmacológico , Hipertrigliceridemia/tratamento farmacológico , Pró-Proteína Convertase 9
9.
São Paulo; 2022. 55 p.
Tese em Português | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-4172

RESUMO

Annually, about 40,000 persons are stricken by snake bite accidents in Brazil, being most of the cases are inflicted by Bothrops genus, whose venom can induce serious pathophysiological effects, mainly disorders in hemostasis. Bothrops jararaca venom is characterized by three main actions: proteolytic, coagulant and hemorrhagic. Some clotting factors can be activated by components present in the venom, classified as pro-coagulant activators, responsible for activating factor X or factor II of the coagulation cascade, generating thrombin. So far, only one procoagulant activator of Bothrops jararaca venom BjV has been characterized, bothrojaractivase, a 23 kDa PI-type metalloproteinase. In this work, we used chromatographic techniques to isolate other procoagulant components of BjV. Thus, by means of affinity chromatographies, BjV was purified on HisTrap and Blue Sepharose resins. Fractions capable of coagulating human fibrinogen and rabbit plasma were obtained, and this last substrate is only coagulated by pro-coagulant activators of BjV. Such fractions with high clotting activity were analyzed, concentrated and their activities on different substrates were differentiated by the use of specific inhibitors of metalloproteinases and serine proteinases. Studies are still being carried out to understand which coagulation factors are being activated by these fractions, by using chromogenic substrates, electrophoresis runs, and mass spectrometry.


Anualmente, cerca de 40.000 pessoas são acometidas por acidentes ofídicos no Brasil, sendo a maioria dos casos decorrentes de serpentes do gênero Bothrops, cujo veneno pode induzir graves efeitos fisiopatológicos, principalmente distúrbios na hemostasia. O veneno da espécie Bothrops jararaca é caracterizado por três ações principais: proteolítica, coagulante e hemorrágica. Relacionado à atividade coagulante, alguns fatores da cascata de coagulação podem ser ativados por componentes presentes no veneno, classificados como ativadores do tipo pró-coagulantes, responsáveis por ativar o fator X ou o fator II da cascata, gerando trombina. Até o momento, apenas um ativador pró-coagulante do veneno de Bothrops jararaca BjV foi caracterizado, a bothrojaractivase, uma metaloproteinase do tipo PI, de 23 kDa. Neste trabalho, utilizamos técnicas cromatográficas para isolar outros componentes pró-coagulantes do BjV. Deste modo, por meio de cromatografias de afinidade, o BjV foi purificado em resinas de HisTrap e Blue Sepharose. Foram obtidas frações capazes de coagular o fibrinogênio humano e plasma de coelho, um substrato que somente é coagulado por enzimas pró-coagulantes do BjV. Tais frações com altas atividades coagulantes foram analisadas, concentradas e suas atividades sobre diferentes substratos foram diferenciadas pelo uso de inibidores específicos de metaloproteinases e serinaproteinases. Obtivemos duas frações parcialmente purificadas, com alta atividade específica, e que são inibidas por quelante de metais divalentes o-fenantrolina. Essas frações são capazes de coagular o plasma de coelho, sem coagular o fibrinogênio humano. Estudos ainda estão sendo realizados para entender quais fatores da cascata de coagulação estas frações ativam, pela utilização de substratos cromogênicos específicos, análises eletroforéticas e espectrometria de massa.

10.
Molecules ; 26(24)2021 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-34946653

RESUMO

This article demonstrates the possibility of producing alkali-activated hybrid cements based on fly ash (FA), and construction and demolition wastes (concrete waste, COW; ceramic waste, CEW; and masonry waste, MAW) using sodium sulfate (Na2SO4) (2-6%) and sodium carbonate (Na2CO3) (5-10%) as activators. From a mixture of COW, CEW, and MAW in equal proportions (33.33%), a new precursor called CDW was generated. The precursors were mixed with ordinary Portland cement (OPC) (10-30%). Curing of the materials was performed at room temperature (25 °C). The hybrid cements activated with Na2SO4 reached compressive strengths of up to 31 MPa at 28 days of curing, and the hybrid cements activated with Na2CO3 yielded compressive strengths of up to 22 MPa. Based on their mechanical performance, the optimal mixtures were selected: FA/30OPC-4%Na2SO4, CDW/30OPC-4%Na2SO4, FA/30OPC-10%Na2CO3, and CDW/30OPC-10%Na2CO3. At prolonged ages (180 days), these mixtures reached compressive strength values similar to those reported for pastes based on 100% OPC. A notable advantage is the reduction of the heat of the reaction, which can be reduced by up to 10 times relative to that reported for the hydration of Portland cement. These results show the feasibility of manufacturing alkaline-activated hybrid cements using alternative activators with a lower environmental impact.

11.
Mol Divers ; 25(3): 1301-1314, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34191245

RESUMO

Abelson kinase (c-Abl) is a non-receptor tyrosine kinase involved in several biological processes essential for cell differentiation, migration, proliferation, and survival. This enzyme's activation might be an alternative strategy for treating diseases such as neutropenia induced by chemotherapy, prostate, and breast cancer. Recently, a series of compounds that promote the activation of c-Abl has been identified, opening a promising ground for c-Abl drug development. Structure-based drug design (SBDD) and ligand-based drug design (LBDD) methodologies have significantly impacted recent drug development initiatives. Here, we combined SBDD and LBDD approaches to characterize critical chemical properties and interactions of identified c-Abl's activators. We used molecular docking simulations combined with tree-based machine learning models-decision tree, AdaBoost, and random forest to understand the c-Abl activators' structural features required for binding to myristoyl pocket, and consequently, to promote enzyme and cellular activation. We obtained predictive and robust models with Matthews correlation coefficient values higher than 0.4 for all endpoints and identified characteristics that led to constructing a structure-activity relationship model (SAR).


Assuntos
Aprendizado de Máquina , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Inibidores de Proteínas Quinases/química , Proteínas Proto-Oncogênicas c-abl/química , Sítios de Ligação , Desenho de Fármacos , Humanos , Ligantes , Estrutura Molecular , Ligação Proteica , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-abl/metabolismo , Relação Quantitativa Estrutura-Atividade
12.
Genes (Basel) ; 10(1)2018 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-30577529

RESUMO

Light signaling pathways interact with the circadian clock to help organisms synchronize physiological and developmental processes to periodic environmental cycles. The plant photoreceptors responsible for clock resetting have been characterized, but signaling components that link the photoreceptors to the clock remain to be identified. Members of the family of NIGHT LIGHT⁻INDUCIBLE AND CLOCK-REGULATED (LNK) genes play key roles linking light regulation of gene expression to the control of daily and seasonal rhythms in Arabidopsis thaliana. Particularly, LNK1 and LNK2 were shown to control circadian rhythms, photomorphogenic responses, and photoperiod-dependent flowering time. Here we analyze the role of the four members of the LNK family in Arabidopsis in these processes. We found that depletion of the closely related LNK3 and LNK4 in a lnk1;lnk2 mutant background affects circadian rhythms, but not other clock-regulated processes such as flowering time and seedling photomorphogenesis. Nevertheless, plants defective in all LNK genes (lnkQ quadruple mutants) display developmental alterations that lead to increased rosette size, biomass, and enhanced phototropic responses. Our work indicates that members of the LNK family have both distinctive and partially overlapping functions, and are an essential link to orchestrate light-regulated developmental processes.

13.
Pesqui. bras. odontopediatria clín. integr ; 18(1): 4343, 15/01/2018. tab, graf
Artigo em Inglês | LILACS, BBO - Odontologia | ID: biblio-967097

RESUMO

Objective: To compare salivary levels of PAI-2 in patients with moderate generalized chronic periodontitis before and after treatment and healthy subjects. Material and Methods: The present case-control study evaluated patients with generalized moderate chronic periodontitis (the case group) and subjects with healthy gingiva (the control group). The healthy subjects were evaluated once and the cases were evaluated twice (before and after treatment) by collecting their salivary samples. ELISA technique was used to determine PAI-2 salivary levels. Data were analyzed with the use of SPSS 17. The level of significance was set at 5%. Results: The mean salivary levels of PAI-2 in the case and control groups were 45.63 ± 8.63 and 22.01 ± 9.77 ng, respectively (p<0.0001). In addition, PAI-2 salivary levels in the case group subjects after treatment was 27.43 ± 5.79 ng, which was lower than that before treatment (45.63 ± 8.63 ng) (p<0.0001). The mean salivary level of PAI-2 in subjects with periodontitis after treatment (27.43 ± 5.79) was not significantly different from that in healthy subjects (22.01 ± 9.77) (p>0.05). Conclusion: The salivary levels of PAI-2 in patient with moderate generalized chronic periodontitis were higher than these in healthy subjects. However, the salivary levels of PAI-2 decreased in the case group subjects after treatment, with no significant difference from the healthy subjects.


Assuntos
Humanos , Masculino , Feminino , Adulto , Saliva , Ensaio de Imunoadsorção Enzimática , Ativadores de Plasminogênio/antagonistas & inibidores , Estudos de Casos e Controles , Periodontite Crônica/diagnóstico , Periodontite/etiologia , Interpretação Estatística de Dados , Irã (Geográfico)
14.
Arch. alerg. inmunol. clin ; 49(1): 5-12, 2018. tab, ilus
Artigo em Espanhol | LILACS | ID: biblio-913710

RESUMO

ntroducción: El sistema del complemento puede ser activado por tres vías: clásica, alternativa y de las lectinas, esta última en fase de estudio para su completamiento. Objetivo: Describir hasta donde se ha avanzado en la construcción de la vía de las lectinas, sus iniciadores, activadores, reguladores, cascada enzimática y sus funciones biológicas. Metodología: Se realizó una revisión sobre el tema en estudio empleando artículos de libre acceso en la base de datos Pubmed y los trabajos publicados por el grupo de trabajo de la Universidad de Goettigen, la Universidad de Aarhus en Dinamarca y el Laboratorio Central de Líquido Cefalorraquídeo (LABCEL) de la Universidad de Ciencias Médicas de La Habana en los últimos cinco años comprendidos en el período de enero de 2012 a marzo del 2017. Desarrollo: Los iniciadores de la vía de las lectinas son las moléculas de reconocimiento colectinas y ficolinas circulantes en sangre, que participan en muchos procesos del organismo. Los activadores de esta vía son las MASP 1, 2 presentes como proenzimas; y la MASP 3, MAp 19 y 44 actúan como reguladoras. La cascada enzimática luego del reconocimiento es similar a la ruta clásica. Conclusiones: Las colectinas y ficolinas inician la vía de las lectinas. Sus activadores son las MASP 1, 2. Los reguladores son la MASP-3, y las MAp 19 y 44. Similar a la clásica en su cascada enzimática. Es la más antigua en la filogenia por eso participa en muchos procesos en el organismo(AU)


Introduction. The complement system can be activated in three ways: classical, alternative and lectins, the latter in the study phase for its completion. Objective. To describe the progress made in the construction of the lectin pathway, its initiators, activators, regulators, enzymatic cascade and its biological functions. Methods. A review was made on the subject under study using articles of free access in the Pubmed database and the works published by the working group of the University of Goettigen, the University of Aarhus in Denmark and the Central Laboratory of Cefalorraquìdeo liquid (LABCEL) of the University of Medical Sciences of Havana in the last five years included in the period from January 2012 to March 2017. Development. The initiators of the lectin pathway are the collectin recognition molecules and circulating ficolins in blood, which participate in many processes of the organism. The activators of this pathway are MASP 1, 2 present as proenzymes; and MASP 3, MAp 19 and 44 act as regulators. The enzymatic cascade after recognition is similar to the classical route. Conclusions. Collectins and ficolines initiate the lectin pathway. Its activators are MASP 1, 2. The regulators are MASP-3, and MAp 19 and 44. Similar to the classic in its enzymatic cascade. It is the oldest in phylogeny so it participates in many processes in the body.(AU)


Assuntos
Humanos , Colectinas , Lectinas , Ativadores de Enzimas , Serina Proteases Associadas a Proteína de Ligação a Manose
15.
Natal; s.n; 23 fev 2017. 122 p. ilus, tab, graf.
Tese em Português | LILACS, BBO - Odontologia | ID: biblio-1427266

RESUMO

O câncer na cavidade oral é uma das lesões malignas mais frequentes na população mundial. Como o processo de desenvolvimento das neoplasias malignas remete a danos que promovem um desequilíbrio na regulação da divisão e morte celular, nos últimos anos, diversos estudos foram realizados com o intuito de verificar a influência desses danos no comportamento global das células e na evolução da doença. Nesse contexto, pesquisas recentes mostraram que alterações na expressão de REG podem desempenhar um importante papel na progressão tumoral de várias neoplasias malignas, por interferir na regulação da apoptose. Diante disso, o objetivo desse trabalho foi investigar a expressão imunoistoquímica dos marcadores REG, p53, MDM-2, Bcl-2 e Bax em carcinomas epidermoides de língua (CELs) oral, com a finalidade de promover uma análise comparativa da imunoexpressão destas proteínas com os parâmetros clínico-patológicos de agressividade da lesão, no intuito de identificar se o REG contribui para a progressão do tumor e se interfere na expressão das proteínas relacionadas a apoptose. Para tanto, foram coletadas informações clínicas de 58 pacientes acometidos por CELs. Em seguida, foi realizada análise histopatológica e imunoistoquímica dos marcadores supracitados, em amostras de material biológico parafinado da lesão. Os resultados mostraram que os tumores com metástase nodal e de alto grau histopatológico de malignidade apresentavam percentuais significativamente menores de REG (p<0,05). Em adição, a análise da expressão de p53, MDM-2 e Bax nos diferentes parâmetros clínico-patológicos avaliados nesse trabalho, não revelou diferenças significativas nos percentuais de imunopositividade desses marcadores. Com relação ao Bcl-2, foi visto que tumores de alto grau de malignidade e com óbitos relacionados a doença apresentavam percentual significativamente menor de positividade dessa proteína (p<0,05). Por fim, o teste de correlação de Spearman demonstrou existir fraca correlação positiva, estatisticamente significativa, entre os percentuais de REG e das proteínas MDM-2 e Bcl-2. Baseado nesses achados, pode-se concluir que a redução da expressão de REG parece contribuir para a progressão do CEL oral e pode influenciar na expressão das proteínas relacionadas a regulação da apoptose (AU).


Cancer of the oral cavity is one of the most common malignancies in the world. Since the development of malignant neoplasms is related to damage that causes an imbalance in the regulation of cell division and cell death, many studies have been conducted in recent years to verify the influence of this damage on overall cell behavior and on the progression of the disease. Within this context, recent studies suggest that changes in the expression of REG play an important role in the progression of different malignant tumors by interfering with the regulation of apoptosis. Therefore, the objective of the present study was to investigate the immunohistochemical expression of REG, p53, MDM-2, Bcl-2 and Bax in oral tongue squamous cell carcinoma (OTSCC), correlating the immunoexpression of these proteins with clinicalpathological parameters of tumor aggressiveness, in order to determine whether REG contributes to tumor progression and interferes with the expression of apoptosisrelated proteins. For this purpose, the clinical data of 58 patients with OTSCC were collected and paraffin-embedded tumor specimens were submitted to histopathological analysis and immunohistochemistry using the markers cited above. The results showed significantly higher expression of REG (p<0.05) in low-grade tumors and without lymph node metastases. In addition, comparison of the expression patterns of p53, MDM-2 and Bax according to the clinical-pathological parameters studied revealed no significant differences in the percentage of immunostaining for these markers. Regarding Bcl-2, a significantly lower percentage of immunostaining for this protein was observed in tumors with a high grade of malignancy and tumors associated with deaths related to the disease (p<0.05). Finally, Spearman's correlation test demonstrated a significant weak positive correlation between the percentages of REG and of MDM-2 and Bcl-2. These findings suggest that the reduced expression of REG contributes to the progression of OTSCC and may influence the expression of proteins related to the regulation of apoptosis (AU).


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Imuno-Histoquímica/métodos , Carcinoma de Células Escamosas/patologia , Proteína Supressora de Tumor p53 , Apoptose , Neoplasias/patologia , Fotomicrografia/métodos , Distribuição de Qui-Quadrado , Estatísticas não Paramétricas
16.
Chem Biol Drug Des ; 87(3): 455-66, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26547388

RESUMO

In this study, quantitative structure-activity relationship studies which make use of molecular dynamics trajectories were performed on a set of 54 glucokinase protein activators. The conformations obtained by molecular dynamics simulation were superimposed according to the twelve alignments tested in a virtual three-dimensional box comprised of 2 Å cells. The models were generated by the technique that combines genetic algorithms and partial least squares. The best alignment models generated with a determination coefficient (r(2)) between 0.674 and 0.743 and cross-validation (q(2)) between 0.509 and 0.610, indicating good predictive capacity. The 4D-QSAR models developed in this study suggest novel molecular regions to be explored in the search for better glucokinase activators.


Assuntos
Glucoquinase/metabolismo , Ativação Enzimática , Humanos , Simulação de Dinâmica Molecular , Relação Quantitativa Estrutura-Atividade
17.
Neuroscience ; 259: 71-83, 2014 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-24316468

RESUMO

Rodents exhibit leptin resistance and high levels of prolactin/placental lactogens during pregnancy. A crosstalk between prolactin and leptin signaling has been proposed as a possible mechanism to explain the changes in energy balance during gestation. However, it remains unclear if specific neuronal populations co-express leptin and prolactin receptors. Therefore, our present study was undertaken to identify in the mouse brain prolactin-responsive cells that possibly express the leptin receptor (LepR). In addition, we assessed the leptin response in different brain nuclei of pregnant and nulliparous mice. We used a LepR-reporter mouse to visualize LepR-expressing cells with the tdTomato fluorescent protein. Prolactin-responsive cells were visualized with the immunohistochemical detection of the phosphorylated form of the signal transducer and activator of transcription-5 (pSTAT5-ir). Notably, many neurons that co-expressed tdTomato and pSTAT5-ir were observed in the medial preoptic area (MPA, 27-48% of tdTomato cells), the retrochiasmatic area (34-51%) and the nucleus of the solitary tract (NTS, 16-24%) of prolactin-treated nulliparous mice, pregnant mice and prolactin-treated leptin-deficient (ob/ob) mice. The arcuate nucleus of the hypothalamus (8-22%), the medial tuberal nucleus (11-15%) and the ventral premammillary nucleus (4-10%) showed smaller percentages of double-labeled cells among the groups. Other brain nuclei did not show significant percentages of neurons that co-expressed tdTomato and pSTAT5-ir. Late pregnant mice exhibited a reduced leptin response in the MPA and NTS when compared with nulliparous mice; however, a normal leptin response was observed in other brain nuclei. In conclusion, our findings shed light on how the brain integrates the information conveyed by leptin and prolactin. Our results corroborate the hypothesis that high levels of prolactin or placental lactogens during pregnancy may directly interfere with LepR signaling, possibly predisposing to leptin resistance.


Assuntos
Encéfalo/metabolismo , Leptina/metabolismo , Gravidez/metabolismo , Prolactina/metabolismo , Análise de Variância , Animais , Encéfalo/citologia , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/fisiologia , Leptina/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Mutação/genética , Paridade/efeitos dos fármacos , Paridade/fisiologia , Gravidez/efeitos dos fármacos , RNA não Traduzido/genética , Receptores para Leptina/genética , Fator de Transcrição STAT3/metabolismo
18.
Rev. méd. Chile ; 139(9): 1118-1127, set. 2011. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-612234

RESUMO

Background: The only accepted treatment for acute ischemic stroke is thrombolysis with recombinant tissue plasminogen activator (t-PA). It was implemented in Chile in 1996, although its use was mainly restricted in Chile to private clinics. Recently, at year 2009, we have implemented this treatment in a public hospital. Aim: To describe the results of treatment of acute ischemic stroke with t-PA in a public hospital in Chile. Material and Methods: Prospective analysis of all eligible patients with acute ischemic stroke that were admitted within 4 hours of its onset and had no contraindications for thrombolysis. Results: In an eight months period, a total of 19 intravenous thrombolyses were performed in 12 males and seven females aged 28 to 79 years old. The mean lapse between onset of symptoms and onset of thrombolysis was 190 ± 57 min. Results were favorable, according to Rankin and National Institute of Health Stroke scales. Ninety days after treatment, 63 percent of patients had minimal or absent disability, 26 percent had moderate disability and only one (5 percent) had severe disability. One patient had a clinically not significant intracranial hemorrhage and one patient died six days after thrombolysis. Conclusions: These results indicate that thrombolysis can be successfully implemented in Chilean public hospitals. The limitations for its use in this setting are mostly administrative.


Assuntos
Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fibrinolíticos/uso terapêutico , Acidente Vascular Cerebral/tratamento farmacológico , Terapia Trombolítica/métodos , Ativador de Plasminogênio Tecidual/uso terapêutico , Chile , Protocolos Clínicos , Hospitais Públicos , Estudos Prospectivos , Proteínas Recombinantes/uso terapêutico , Reprodutibilidade dos Testes , Resultado do Tratamento
19.
Rev. chil. endocrinol. diabetes ; 4(3): 194-197, jul. 2011. ilus, tab, graf
Artigo em Espanhol | LILACS | ID: lil-640638

RESUMO

Thyroid hormone resistance (RTH) is inherited as an autosomal dominant trait, with variable clinical presentations. The hallmark of the syndrome is a variable degree of resistance to thyroid hormones, with high levels of circulating thyroid hormones, inappropriately normal or elevated TSH values and a clinical pattern of mixed hypothyroidism and hyperthyroidism. RTH is related in more than 85 percent of cases to thyroid hormone beta receptor mutations. We report a 11 years female with a history of treatment with propylthiouracil (PTU) for hyperthyroidism, presenting with a progressive goiter. Thyroidectomy was performed, removing 233 grams of thyroid tissue showing follicular hyperplasia. After surgery, a fast growth of the remnant thyroid gland was observed along with tachycardia. Laboratory showed a TSH of 38 mU/mL a triiodothyronine level of 300 ng/dL a thyroxin level of 14.8 ug/dL and a free thyroxin of 3.19 ng/dL, suggesting the diagnosis of RTH. The molecular study was negative for mutation of the beta isoform of thyroid hormone receptor. The possible theories that can explain these findings are discussed.


Assuntos
Humanos , Feminino , Criança , Hipertireoidismo/tratamento farmacológico , Síndrome da Resistência aos Hormônios Tireóideos/diagnóstico , Tiroxina/administração & dosagem , Relação Dose-Resposta a Droga , Hipertireoidismo/cirurgia , Período Pós-Operatório , Síndrome da Resistência aos Hormônios Tireóideos/etiologia , Tireoidectomia
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