Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 223
Filtrar
Mais filtros

País/Região como assunto
Intervalo de ano de publicação
1.
J Virol ; 98(1): e0110223, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38169294

RESUMO

Mayaro virus (MAYV) is an emerging arbovirus member of the Togaviridae family and Alphavirus genus. MAYV infection causes an acute febrile illness accompanied by persistent polyarthralgia and myalgia. Understanding the mechanisms involved in arthritis caused by alphaviruses is necessary to develop specific therapies. In this work, we investigated the role of the CCL2/CCR2 axis in the pathogenesis of MAYV-induced disease. For this, wild-type (WT) C57BL/6J and CCR2-/- mice were infected with MAYV subcutaneously and evaluated for disease development. MAYV infection induced an acute inflammatory disease in WT mice. The immune response profile was characterized by an increase in the production of inflammatory mediators, such as IL-6, TNF, and CCL2. Higher levels of CCL2 at the local and systemic levels were followed by the significant recruitment of CCR2+ macrophages and a cellular response orchestrated by these cells. CCR2-/- mice showed an increase in CXCL-1 levels, followed by a replacement of the macrophage inflammatory infiltrate by neutrophils. Additionally, the absence of the CCR2 receptor protected mice from bone loss induced by MAYV. Accordingly, the silencing of CCL2 chemokine expression in vivo and the pharmacological blockade of CCR2 promoted a partial improvement in disease. Cell culture data support the mechanism underlying the bone pathology of MAYV, in which MAYV infection promotes a pro-osteoclastogenic microenvironment mediated by CCL2, IL-6, and TNF, which induces the migration and differentiation of osteoclast precursor cells. Overall, these data contribute to the understanding of the pathophysiology of MAYV infection and the identification future of specific therapeutic targets in MAYV-induced disease.IMPORTANCEThis work demonstrates the role of the CCL2/CCR2 axis in MAYV-induced disease. The infection of wild-type (WT) C57BL/6J and CCR2-/- mice was associated with high levels of CCL2, an important chemoattractant involved in the recruitment of macrophages, the main precursor of osteoclasts. In the absence of the CCR2 receptor, there is a mitigation of macrophage migration to the target organs of infection and protection of these mice against bone loss induced by MAYV infection. Much evidence has shown that host immune response factors contribute significantly to the tissue damage associated with alphavirus infections. Thus, this work highlights molecular and cellular targets involved in the pathogenesis of arthritis triggered by MAYV and identifies novel therapeutic possibilities directed to the host inflammatory response unleashed by MAYV.


Assuntos
Infecções por Alphavirus , Artrite , Quimiocina CCL2 , Receptores CCR2 , Animais , Camundongos , Alphavirus , Infecções por Alphavirus/imunologia , Artrite/imunologia , Artrite/virologia , Quimiocina CCL2/imunologia , Interleucina-6/imunologia , Camundongos Endogâmicos C57BL , Receptores CCR2/imunologia , Camundongos Knockout , Masculino , Doenças Ósseas/virologia
2.
Pediatr Res ; 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38499628

RESUMO

BACKGROUND: The current study mainly focused on provide further insights into the association of the miR-22-3p and miR-29c-3p expression in CFU-Hill colonies with birth weight and senescence process in children. METHODS: This cross-sectional study evaluated 61 children (32 boys, 29 girls). The CFU-Hill colonies number was evaluated in vitro by cell culture technique and senescence was detected by ß-galactosidase (SA-ß-Gal) assay. Expression of miR-22-3p and miR-29c-3p isolated from CFU-Hill colonies were detected using quantitative real-time polymerase chain reaction. RESULTS: Birth weight was correlated with both CFU-Hill colonies and %SA-ß-Gal positive staining. Multivariate linear regression analysis revealed that the senescence was a predictor of the lower CFU-Hill colonies number, while only the birth weight was a predictor of senescence of CFU-Hill colonies. Overexpression of miR-22-3p and miR-29c-3p was observed in CFU-Hill colonies isolated from children with low birth weight (LBW). Interestingly, we found a significant correlation between %SA-ß-Gal cells staining positive for both miR-22-3p and miR-29c-3p. CONCLUSION: The LBW is associated with decreased CFU-Hill colonies number and high senescence of these cells. The overexpression of miR-22-3p and miR-29c-3p may be partially responsible for this alteration due to regulation of several pathways related to the senescence process. IMPACT: The study establishes a significant correlation between birth weight and the number of CFU-Hill colonies, suggesting that birth weight could be a predictive biomarker for vascular health in children. Data indicates that cellular senescence is a predictor of reduced CFU-Hill colony numbers. This suggests that the aging process of these cells could be an important factor in understanding the vascular health issues in children with low birth weight. The overexpression of miR-22-3p and miR-29c-3p in children with low birth weight and their correlation with increased cellular senescence highlight these microRNAs as possible molecular mechanisms influencing the aging of CFU-Hill colonies.

3.
Adv Exp Med Biol ; 1443: 187-209, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38409422

RESUMO

Innovative techniques such as the "omics" can be a powerful tool for the understanding of intracellular pathways involved in homeostasis maintenance and identification of new potential therapeutic targets against endocrine-metabolic disorders. Over the last decades, proteomics has been extensively applied in the study of a wide variety of human diseases, including those involving the endocrine system. Among the most endocrine-related disorders investigated by proteomics in humans are diabetes mellitus and thyroid, pituitary, and reproductive system disorders. In diabetes, proteins implicated in insulin signaling, glucose metabolism, and ß-cell activity have been investigated. In thyroid diseases, protein expression alterations were described in thyroid malignancies and autoimmune thyroid illnesses. Additionally, proteomics has been used to investigate the variations in protein expression in adrenal cancers and conditions, including Cushing's syndrome and Addison's disease. Pituitary tumors and disorders including acromegaly and hypopituitarism have been studied using proteomics to examine changes in protein expression. Reproductive problems such as polycystic ovarian syndrome and endometriosis are two examples of conditions where alterations in protein expression have been studied using proteomics. Proteomics has, in general, shed light on the molecular underpinnings of many endocrine-related illnesses and revealed promising biomarkers for both their detection and treatment. The capacity of proteomics to thoroughly and objectively examine complex protein mixtures is one of its main benefits. Mass spectrometry (MS) is a widely used method that identifies and measures proteins based on their mass-to-charge ratio and their fragmentation pattern. MS can perform the separation of proteins according to their physicochemical characteristics, such as hydrophobicity, charge, and size, in combination with liquid chromatography. Other proteomics techniques include protein arrays, which enable the simultaneous identification of several proteins in a single assay, and two-dimensional gel electrophoresis (2D-DIGE), which divides proteins depending on their isoelectric point and molecular weight. This chapter aims to summarize the most relevant proteomics data from targeted tissues, as well as the daily rhythmic variation of relevant biomarkers in both physiological and pathophysiological conditions within the involved endocrine system, especially because the actual modern lifestyle constantly imposes a chronic unentrained condition, which virtually affects all the circadian clock systems within human's body, being also correlated with innumerous endocrine-metabolic diseases.


Assuntos
Doenças do Sistema Endócrino , Multiômica , Humanos , Espectrometria de Massas , Proteínas , Doenças do Sistema Endócrino/genética , Sistema Endócrino , Biomarcadores
4.
Int J Mol Sci ; 25(9)2024 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-38732010

RESUMO

L-asparaginase is an essential drug used to treat acute lymphoid leukemia (ALL), a cancer of high prevalence in children. Several adverse reactions associated with L-asparaginase have been observed, mainly caused by immunogenicity and allergenicity. Some strategies have been adopted, such as searching for new microorganisms that produce the enzyme and applying protein engineering. Therefore, this work aimed to elucidate the molecular structure and predict the immunogenic profile of L-asparaginase from Penicillium cerradense, recently revealed as a new fungus of the genus Penicillium and producer of the enzyme, as a motivation to search for alternatives to bacterial L-asparaginase. In the evolutionary relationship, L-asparaginase from P. cerradense closely matches Aspergillus species. Using in silico tools, we characterized the enzyme as a protein fragment of 378 amino acids (39 kDa), including a signal peptide containing 17 amino acids, and the isoelectric point at 5.13. The oligomeric state was predicted to be a homotetramer. Also, this L-asparaginase presented a similar immunogenicity response (T- and B-cell epitopes) compared to Escherichia coli and Dickeya chrysanthemi enzymes. These results suggest a potentially useful L-asparaginase, with insights that can drive strategies to improve enzyme production.


Assuntos
Asparaginase , Simulação por Computador , Penicillium , Asparaginase/química , Asparaginase/imunologia , Asparaginase/metabolismo , Penicillium/imunologia , Penicillium/enzimologia , Sequência de Aminoácidos , Proteínas Fúngicas/química , Proteínas Fúngicas/imunologia , Proteínas Fúngicas/metabolismo , Epitopos de Linfócito B/imunologia , Epitopos de Linfócito B/química , Epitopos de Linfócito T/imunologia , Epitopos de Linfócito T/química , Humanos , Aspergillus/imunologia , Aspergillus/enzimologia , Escherichia coli/genética , Dickeya chrysanthemi/enzimologia , Dickeya chrysanthemi/imunologia , Modelos Moleculares
5.
Cell Mol Neurobiol ; 44(1): 10, 2023 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-38141078

RESUMO

Rhythmic regulations are virtually described in all physiological processes, including central nervous system development and immunologic responses. Zika virus (ZIKV), a neurotropic arbovirus, has been recently linked to a series of birth defects and neurodevelopmental disorders. Given the well-characterized role of the intrinsic cellular circadian clock within neurogenesis, cellular metabolism, migration, and differentiation among other processes, this study aimed to characterize the influence of ZIKV infection in the circadian clock expression in human neuronal cells. For this, in vitro models of human-induced neuroprogenitor cells (hiNPCs) and neuroblastoma cell line SH-SY5Y, cultured as monolayer and neurospheres, were infected by ZIKV, followed by RNA-Seq and RT-qPCR investigation, respectively. Targeted circadian clock components presented mRNA oscillations only after exogenous synchronizing stimuli (Forskolin) in SH-SY5Y monolayer culture. Interestingly, when these cells were grown as 3D-arranged neurospheres, an intrinsic oscillatory expression pattern was observed for some core clock components without any exogenous stimulation. The ZIKV infection significantly disturbed the mRNA expression pattern of core clock components in both neuroblastoma cell culture models, which was also observed in hiNPCs infected with different strains of ZIKV. The ZIKV-mediated desynchronization of the circadian clock expression in human cells might further contribute to the virus impairment of neuronal metabolism and function observed in adults and ZIKV-induced congenital syndrome. In vitro models of Zika virus (ZIKV) neuronal infection. Human neuroprogenitor cells were cultured as monolayer and neurospheres and infected by ZIKV. Monolayer-cultured cells received forskolin (FSK) as a coupling factor for the circadian clock rhythmicity, while 3D-arranged neurospheres showed an intrinsic oscillatory pattern in the circadian clock expression. The ZIKV infection affected the mRNA expression pattern of core clock components in both cell culture models. The ZIKV-mediated desynchronization of the circadian clock machinery might contribute to the impairment of neuronal metabolism and function observed in both adults (e.g., Guillain-Barré syndrome) and ZIKV-induced congenital syndrome (microcephaly). The graphical abstract has been created with Canva at the canva.com website.


Assuntos
Relógios Circadianos , Neuroblastoma , Infecção por Zika virus , Zika virus , Adulto , Humanos , Zika virus/genética , Colforsina , RNA Mensageiro/genética
6.
Eur J Clin Microbiol Infect Dis ; 42(7): 873-882, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37160574

RESUMO

Acute respiratory infections (ARIs) are caused by a variety of microorganisms. Of all ARIs, 80% are caused by viruses such as human respiratory syncytial virus, metapneumovirus, influenza, parainfluenza, rhinovirus, and, more recently, Sars-CoV-2, which has been responsible for the COVID-19 pandemic. The objective of our study was to evaluate clinical data from a viral panel performed in children hospitalized with SARS or COVID-19 in the infirmary or ICU of 5 pediatric hospitals in the city of Goiânia, Goiás, Brazil. Demographic, clinical, and laboratory data were collected for analysis, and data on the outcomes underwent statistical treatment. A total of 128 patients were selected for the study, 54% of whom were male and 46% female. The viral panel included rhinovirus, COVID-19, metapneumovirus, adenovirus, and parainfluenza. Descriptive analyses of age profile showed differences in the involvement of particular viruses. The percentage of patients who required hospitalization in the ICU, infirmary, as well as individuals who were discharged after therapy or who died, were described. Our work shows that epidemiological surveillance measures are indispensable, especially if used in the continued analysis of viral panels in all pediatric patients with SARS.


Assuntos
COVID-19 , Metapneumovirus , Infecções por Paramyxoviridae , Infecções Respiratórias , Vírus , Criança , Humanos , Masculino , Feminino , Lactente , Pandemias , COVID-19/epidemiologia , SARS-CoV-2 , Infecções Respiratórias/epidemiologia , Infecções por Paramyxoviridae/epidemiologia , Rhinovirus
7.
Ann Hematol ; 101(11): 2507-2513, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36094534

RESUMO

The complexity and costs of hematopoietic cell transplantation (HCT) have increased over the last decades with the popularization of unrelated donor (URD) transplantation and the introduction of haploidentical transplantation with posttransplant cyclophosphamide. Few studies have addressed this issue. The objective of this study was to analyze HCT costs in a single FACT-accredited private non-profit hospital. We included 79 patients who underwent HCT between 2018 and 2020. We have included all costs from admission day until D + 180. We used a lognormal regression. Median age was 53 y/o and most donors were unrelated (51%). Costs were higher with haploidentical donor (42%, p = 0.017, compared with URD), higher HCT-CI (15% for each point, p = 0.0056), and in patients with liver or gastrointestinal GVHD (45%, p = 0.033), and lower in patients who received CD34 > 2.5 × 10E6/kg (42%, p = 0.0038). We built a score based on the following risk factors: HCT-CI > 3, CD34 ≤ 2.5 × 10E6/kg, haploidentical donor, and donor age > 30 y/o. Patients with 2 + risk factors (N = 53) had a median cost of USD 226,156.00, compared with USD 93,048.00 in patients with zero or 1 point (N = 26, p < 0.0001). In summary, we have shown that HCT costs are higher with lower doses of CD34 cells, haploidentical HCT (provided that the costs of stem cell procurement and ATG are not included), and in patients with higher HCT-CI. Prospective and refined cost analyses comparing haploidentical and URD transplants, as well as effective strategies for patients with higher HCT-CI scores, are warranted. We found no difference in costs between URD and MSD transplantation.


Assuntos
Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Brasil , Ciclofosfamida , Estresse Financeiro , Doença Enxerto-Hospedeiro/etiologia , Doença Enxerto-Hospedeiro/prevenção & controle , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos , Estudos Retrospectivos , Fatores de Risco , Irmãos , Condicionamento Pré-Transplante , Doadores não Relacionados
8.
Adv Physiol Educ ; 46(3): 351-357, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35549509

RESUMO

The COVID-19 pandemic affected almost all aspects of our lives, including the education sector and the way of teaching and learning. In March 2020, health authorities in Brazil imposed social isolation and the interruption of on-site activities in schools and universities. In this context, the Federal University of Minas Gerais (UFMG), one of the largest universities in Brazil and Latin America, developed an emergency remote learning (ERL) plan that allowed the return of classes in an online format and supported students to obtain access to equipment and internet network. Within this new perspective, the Undergraduate Teaching Assistant (UTA) program of the Department of Physiology and Biophysics (DFIB) explored strategies to minimize the impact of the absence of face-to-face classes. Using different available tools in online platforms and social media such as Microsoft Teams, YouTube animated video classes, and Instagram, the UTA program assisted >500 undergraduate students and strongly supported professors during ERL. In just over a year, our video classes on YouTube Channel reached ∼40,000 views. Most of the students reported that their questions were fully and quickly solved by the UTA program. Collectively, our results indicate that the strategies implemented by the UTA program helped the undergraduate students and professors to adapt to a remote learning format.


Assuntos
COVID-19 , Educação a Distância , Biofísica , Educação a Distância/métodos , Humanos , Pandemias , Estudantes
9.
Molecules ; 26(22)2021 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-34834154

RESUMO

The purpose of this systematic review was to identify the available literature of production, purification, and characterization of proteases by endophytic fungi. There are few complete studies that entirely exhibit the production, characterization, and purification of proteases from endophytic fungi. This study followed the PRISMA, and the search was conducted on five databases: PubMed, PMC, Science Direct, Scopus Articles, and Web of Science up until 18 May 2021, with no time or language restrictions. The methodology of the selected studies was evaluated using GRADE. Protease production, optimization, purification, and characterization were the main evaluated outcomes. Of the 5540 initially gathered studies, 15 met the inclusion criteria after a two-step selection process. Only two studies optimized the protease production using statistical design and two reported enzyme purification and characterization. The genus Penicillium and Aspergillus were the most cited among the eleven different genera of endophytic fungi evaluated in the selected articles. Six studies proved the ability of some endophytic fungi to produce fibrinolytic proteases, demonstrating that endophytic fungi can be exploited for the further production of agents used in thrombolytic therapy. However, further characterization and physicochemical studies are required to evaluate the real potential of endophytic fungi as sources of industrial enzymes.


Assuntos
Aspergillus/enzimologia , Endófitos/enzimologia , Proteínas Fúngicas/biossíntese , Penicillium/enzimologia , Peptídeo Hidrolases/biossíntese , Proteínas Fúngicas/química , Peptídeo Hidrolases/química
10.
Diabetologia ; 63(9): 1822-1835, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32472193

RESUMO

AIMS/HYPOTHESIS: During pregnancy, maternal metabolic disease and hormonal imbalance may alter fetal beta cell development and/or proliferation, thus leading to an increased risk for developing type 2 diabetes in adulthood. Although thyroid hormones play an important role in fetal endocrine pancreas development, the impact of maternal hypothyroidism on glucose homeostasis in adult offspring remains poorly understood. METHODS: We investigated this using a mouse model of hypothyroidism, induced by administration of an iodine-deficient diet supplemented with propylthiouracil during gestation. RESULTS: Here, we show that, when fed normal chow, adult mice born to hypothyroid mothers were more glucose-tolerant due to beta cell hyperproliferation (two- to threefold increase in Ki67-positive beta cells) and increased insulin sensitivity. However, following 8 weeks of high-fat feeding, these offspring gained 20% more body weight, became profoundly hyperinsulinaemic (with a 50% increase in fasting insulin concentration), insulin-resistant and glucose-intolerant compared with controls from euthyroid mothers. Furthermore, altered glucose metabolism was maintained in a second generation of animals. CONCLUSIONS/INTERPRETATION: Therefore, gestational hypothyroidism induces long-term alterations in endocrine pancreas function, which may have implications for type 2 diabetes prevention in affected individuals.


Assuntos
Glicemia/metabolismo , Intolerância à Glucose/metabolismo , Hipotireoidismo/metabolismo , Células Secretoras de Insulina/metabolismo , Ilhotas Pancreáticas/embriologia , Complicações na Gravidez/metabolismo , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Animais , Antitireóideos/toxicidade , Proliferação de Células , Dieta Hiperlipídica , Modelos Animais de Doenças , Feminino , Hiperinsulinismo/metabolismo , Resistência à Insulina , Iodo/deficiência , Ilhotas Pancreáticas/metabolismo , Camundongos , Gravidez , Propiltiouracila/toxicidade , Estresse Fisiológico
11.
J Cardiovasc Pharmacol ; 76(6): 715-729, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32976209

RESUMO

Perivascular adipose tissue (PVAT) modulates the vascular tone. Hydrogen sulfide (H2S) is synthetized by cystathionine gamma-lyase (CSE) in brown PVAT. Modulation of vascular contractility by H2S is, in part, adenosine triphosphate (ATP)-sensitive potassium channels dependent. However, the role of PVAT-derived H2S in hypertensive pregnancy (HTN-Preg) is unclear. Therefore, we aimed to examine the involvement of H2S in the anticontractile effect of PVAT in aortae from normotensive and hypertensive pregnant rats. To this end, phenylephrine-induced contractions in the presence and absence of PVAT and endothelium in aortae from normotensive pregnant (Norm-Preg) and HTN-Preg rats were investigated. Maternal blood pressure, fetal-placental parameters, angiogenesis-related biomarkers, and H2S levels were also assessed. We found that circulating H2S is elevated in hypertensive pregnancy associated with angiogenic imbalance, fetal and placental growth restrictions, which revealed that there is H2S pathway activation. Moreover, under stimulated H2S formation PVAT, but not endothelium, reduced phenylephrine-induced contractions in aortae from HTN-Preg rats. Also, H2S synthesis inhibitor abolished anticontractile effects of PVAT and endothelium. Furthermore, anticontractile effect of PVAT, but not of endothelium, was eliminated by ATP-sensitive potassium channels blocker. In accordance, increases in H2S levels in PVAT and placenta, but not in aortae without PVAT, were also observed. In conclusion, anticontractile effect of PVAT is lost, at least in part, in HTN-Preg aortae and PVAT effect is ATP-sensitive potassium channels dependent in normotensive and hypertensive pregnant rat aortae. PVAT but not endothelium is responsive to the H2S stimulation in hypertensive pregnant rat aortae, implying a key role for PVAT-derived H2S under endothelial dysfunction.


Assuntos
Tecido Adiposo/metabolismo , Aorta Torácica/metabolismo , Endotélio Vascular/metabolismo , Sulfeto de Hidrogênio/metabolismo , Hipertensão Induzida pela Gravidez/metabolismo , Vasoconstrição , Adaptação Fisiológica , Tecido Adiposo/fisiopatologia , Animais , Aorta Torácica/fisiopatologia , Acetato de Desoxicorticosterona , Modelos Animais de Doenças , Endotélio Vascular/fisiopatologia , Feminino , Retardo do Crescimento Fetal/metabolismo , Retardo do Crescimento Fetal/fisiopatologia , Hipertensão Induzida pela Gravidez/etiologia , Hipertensão Induzida pela Gravidez/fisiopatologia , Canais KATP/metabolismo , Gravidez , Ratos Wistar , Transdução de Sinais , Cloreto de Sódio na Dieta , Regulação para Cima
12.
Clin Exp Pharmacol Physiol ; 47(5): 857-866, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31943292

RESUMO

Asparaginase is fundamental to the treatment of haematological malignancies. However, little has been studied on the effects that asparaginase could exert on solid tumours. Thus, this study aimed to evaluate the effects of asparaginase on an oral carcinoma cell line. The cytotoxicity of asparaginase in SCC-9 (tongue squamous cell carcinoma) and HaCaT (human keratinocyte) cell lines was evaluated with MTT cell viability assay. The cells were treated with asparaginase at 0.04, 0.16, 0.63, 1.0, 1.5, 2.5, and 5.0 IU/mL. Dose-response curves and IC50 values were obtained and the Tumour Selectivity Index (TSI) was calculated. The effect of asparaginase on procaspase-3 and nuclear factor κB (NFκB) expression was evaluated with western blot because it was reported that the overexpression of NFκB has been shown to contribute to tumour cell survival, proliferation, and migration. Caspase 3/7 staining was performed to identify cell death using flow cytometry. Effective asparaginase concentrations were lower for SCC-9 cells when compared to HaCaT cells. The cytotoxicity results at 48 and 72 hours were significantly different for SCC-9 cells. The TSI indicated that asparaginase was selective for the tumour cells. A decrease in procaspase-3 and NFκB protein levels was observed in SCC-9 cells. Furthermore, asparaginase resulted in significant apoptosis after 48 and 72 hours. Based on these results, asparaginase was cytotoxic in a dose- and time-dependent manner, induces apoptosis, and reduces NFκB expression in oral cancer cells. These results encourage further studies on the effectiveness of this enzyme as a treatment for solid tumours, especially head and neck cancer.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Asparaginase/farmacologia , NF-kappa B/metabolismo , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Neoplasias da Língua/tratamento farmacológico , Caspase 3/metabolismo , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Regulação para Baixo , Células HaCaT , Humanos , Transdução de Sinais , Carcinoma de Células Escamosas de Cabeça e Pescoço/metabolismo , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Fatores de Tempo , Neoplasias da Língua/metabolismo , Neoplasias da Língua/patologia
13.
Curr Microbiol ; 77(9): 2300-2306, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32494882

RESUMO

Acinetobacter baumannii is an emerging pathogen associated with nosocomial infections and multidrug resistance. Polymyxin B has been used to treat infections caused by multidrug-resistant (MDR) A. baumannii but an increase in polymyxin B resistance has been observed. We aimed to determine the diversity, antimicrobial susceptibility, presence of polymyxin B heteroresistance and adaptive resistance in 72 A. baumannii clinical isolates from two public hospitals in Rio de Janeiro. The isolates were identified by sequencing of rpoB gene. Determination of the genetic diversity of isolates was performed by pulsed-field gel electrophoresis and oxacillinases genes were detected by polymerase chain reaction. The polymyxin B heteroresistance was analyzed by population analysis profile and adaptive resistance was evaluated after serial daily passages of isolates in broth containing increasing polymyxin B concentrations. The results showed that 49% of the isolates were collected from respiratory system and 62% were MDR, while 35% were extensively drug resistant. Additionally, all the isolates carried blaOXA-23-like, blaOXA-51-like genes and ISAba1, while 1% had blaOXA-24-like gene. The association of ISAba1-blaOXA-23 was found in 96% of the isolates. Polymyxin B heteroresistance was found in 36% of the isolates and polymyxin B adaptive resistance was not found in the isolates. Our study demonstrated the high resistance to antimicrobials used in clinical practice and the spread of oxacillinases genes and insertion sequence (IS). We also reported the presence of heteroresistance to polymyxin B used as a last-resort therapy for MDR A. baumannii.


Assuntos
Infecções por Acinetobacter , Acinetobacter baumannii , Preparações Farmacêuticas , Acinetobacter baumannii/genética , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Brasil , Farmacorresistência Bacteriana Múltipla/genética , Humanos , Testes de Sensibilidade Microbiana , Polimixina B/farmacologia , beta-Lactamases
14.
J Infect Dis ; 219(6): 964-974, 2019 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-30307561

RESUMO

BACKGROUND: Tuberculous pneumonia, necrotic granulomatous lesions, and bacterial dissemination characterize severe forms of mycobacterial infection. METHODS: To evaluate the pulmonary CD4+ T-cell response during severe tuberculosis, C57BL/6 mice were infected with approximately 100 bacilli of 3 hypervirulent mycobacterial isolates (Mycobacterium tuberculosis strain Beijing 1471 and Mycobacterium bovis strains B2 and MP287/03) or the H37Rv M tuberculosis strain as reference for mycobacterial virulence. Because high expression of both CD39 and CD73 ectonucleotidases was detected on parenchymal CD4+ T cells, we investigated whether CD4+ T-cell suppression in the context of severe disease was due to the extracellular adenosine accumulation that resulted from tissue damage. RESULTS: Lowest expression of CD69, which is an activation marker implicated in maintaining cells in tissues, was observed in lungs from mice displaying the most severe pulmonary pathology. Reduced interferon (IFN)γ-producing CD4+ T cells were also found in the lung of these mice. Intranasal administration of the adenosine receptor antagonist caffeine substantially enhanced the frequency and number of parenchymal CD4+ T cells as well as both CD69 expression and IFNγ production. CONCLUSIONS: These results indicate that adenosine, which may be generated by extracellular adenosine triphosphate degradation, impairs the parenchymal CD4+ T-cell response and contributes to the development of severe tuberculosis.


Assuntos
Linfócitos T CD4-Positivos/patologia , Pulmão/patologia , Tuberculose Pulmonar/patologia , 5'-Nucleotidase/metabolismo , Animais , Antígenos CD/metabolismo , Antígenos de Diferenciação de Linfócitos T/metabolismo , Cafeína/farmacologia , Interferon gama/metabolismo , Lectinas Tipo C/metabolismo , Pulmão/microbiologia , Camundongos Endogâmicos C57BL , Mycobacterium bovis/patogenicidade , Mycobacterium tuberculosis/patogenicidade , Antagonistas de Receptores Purinérgicos P1/farmacologia , Receptores Purinérgicos P1/metabolismo , Transdução de Sinais , Tuberculose Pulmonar/microbiologia
15.
Am Heart J ; 215: 187-197, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31349110

RESUMO

BACKGROUND: Appropriate dietary recommendations represent a key part of secondary prevention in cardiovascular disease (CVD). We evaluated the effectiveness of the implementation of a nutritional program on quality of diet, cardiovascular events, and death in patients with established CVD. METHODS: In this open-label, multicenter trial conducted in 35 sites in Brazil, we randomly assigned (1:1) patients aged 45 years or older to receive either the BALANCE Program (experimental group) or conventional nutrition advice (control group). The BALANCE Program included a unique nutritional education strategy to implement recommendations from guidelines, adapted to the use of affordable and regional foods. Adherence to diet was evaluated by the modified Alternative Healthy Eating Index. The primary end point was a composite of all-cause mortality, cardiovascular death, cardiac arrest, myocardial infarction, stroke, myocardial revascularization, amputation, or hospitalization for unstable angina. Secondary end points included biochemical and anthropometric data, and blood pressure levels. RESULTS: From March 5, 2013, to Abril 7, 2015, a total of 2534 eligible patients were randomly assigned to either the BALANCE Program group (n = 1,266) or the control group (n = 1,268) and were followed up for a median of 3.5 years. In total, 235 (9.3%) participants had been lost to follow-up. After 3 years of follow-up, mean modified Alternative Healthy Eating Index (scale 0-70) was only slightly higher in the BALANCE group versus the control group (26.2 ±â€¯8.4 vs 24.7 ±â€¯8.6, P < .01), mainly due to a 0.5-serving/d greater intake of fruits and of vegetables in the BALANCE group. Primary end point events occurred in 236 participants (18.8%) in the BALANCE group and in 207 participants (16.4%) in the control group (hazard ratio, 1.15; 95% CI 0.95-1.38; P = .15). Secondary end points did not differ between groups after follow-up. CONCLUSIONS: The BALANCE Program only slightly improved adherence to a healthy diet in patients with established CVD and had no significant effect on the incidence of cardiovascular events or death.


Assuntos
Doenças Cardiovasculares/prevenção & controle , Dieta/normas , Programas Nacionais de Saúde/normas , Avaliação Nutricional , Estado Nutricional , Desenvolvimento de Programas/métodos , Prevenção Secundária/métodos , Brasil/epidemiologia , Doenças Cardiovasculares/epidemiologia , Causas de Morte/tendências , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Taxa de Sobrevida/tendências
16.
Chem Res Toxicol ; 32(6): 986-994, 2019 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-30931558

RESUMO

Humans and environments are constantly exposed to a wide range of commercial products containing silver nanoparticles (AgNPs) in their composition. The hypothalamic-pituitary-testicular (HP-testicular) axis is sensitive to low doses of AgNPs with repercussions in sperm functionality. The oxidative stress may be related to the pathogenesis of sperm alterations because Ag+ ions are released from AgNPs in the corporal fluids. This study aimed to investigate the effects of AgNP exposure in the antioxidant defense system. For this, the transcript expression and the activity of catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPX), and glutathione reductase (GSR) enzymes were evaluated in the testis of rats exposed during the prepubertal period to increasing doses of AgNPs (1.875, 3.75, 7.5, or 15 µg of AgNPs/kg). The higher dose of AgNPs (15 µg/kg) investigated promoted increases in the activity of CAT, GPX, and GSR enzymes and in the expression of Gpx4 var1 transcript. The exposure to 7.5 µg/kg of AgNP increased the Gpx4 var1 mRNA expression. In the group that received 3.75 µg of AgNP/kg, the expression of Sod1, Gpx4 var2, and Gsr transcripts was decreased while the Gpx4 var1 mRNA expression was augmented. The lower dose of AgNPs tested (1.875 µg/kg) increased the expression of Cat and Gpx4 var1 transcripts. Thus, AgNP alters the expression and activity of the antioxidant enzymes in a nonmonotonic dose-response curve and directly or indirectly modulates the events related to spermatogenesis process.


Assuntos
Antioxidantes/metabolismo , Nanopartículas Metálicas/química , Prata/farmacologia , Testículo/efeitos dos fármacos , Administração Oral , Animais , Catalase/metabolismo , Relação Dose-Resposta a Droga , Glutationa/metabolismo , Glutationa Redutase/metabolismo , Masculino , Nanopartículas Metálicas/administração & dosagem , RNA Mensageiro/biossíntese , RNA Mensageiro/efeitos dos fármacos , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/análise , Espécies Reativas de Oxigênio/metabolismo , Prata/administração & dosagem , Superóxido Dismutase/metabolismo , Testículo/metabolismo
17.
Appl Microbiol Biotechnol ; 103(13): 5161-5166, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31104099

RESUMO

L-asparaginase is an enzyme produced by microorganisms, plants, and animals, which is used clinically for the treatment for acute lymphoblastic leukemia (ALL) and, in the food industry, to control acrylamide formation in baked foods. The purpose of this review was to evaluate the available literature regarding microbial sources of L-asparaginase, culture media used to achieve maximum enzyme expression in microbial fermentations, and assay methods employed to assess L-asparaginase activity. Studies were gathered by searching PubMed, and Web of Science databases before January 22, 2018, with no time restrictions. The articles were evaluated according to the source of L-asparaginase being studied, the nitrogen source in the culture medium, the type of sample, and the method employed to evaluate L-asparaginase activity. Bacterial L-asparaginase appeared to be the most commonly studied source of the enzyme and, most often, the enzyme activity was assayed from crude protein extracts using the Nessler method, which is an indirect measurement of asparaginase activity that determines the concentration of ammonia generated after the action of the enzyme on the substrate, L-asparagine. However, ammonia is also generated throughout microbial fermentations and this endogenous ammonia will also reduce the Nessler reagent if crude microbial extracts are used to determine total L-asparaginase activity. We suggest that current estimates of L-asparaginase activity reported in the literature may be overestimated when Nessler reagent is used, since we were unable to find a single study that made reference to the possible inference of fermentation derived ammonia.


Assuntos
Asparaginase/metabolismo , Bactérias/enzimologia , Bioensaio/normas , Amônia/metabolismo , Asparagina/metabolismo , Bioensaio/métodos , Meios de Cultura , Fermentação
18.
Bioorg Med Chem Lett ; 26(13): 3177-3181, 2016 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-27209234

RESUMO

An efficient and rapid process for N-glycosylation of 5-(1-(3-fluorophenyl)-1H-pyrazol-4-yl)-2H-tetrazole-LQFM 021 (1), a new synthetic derivative of pyrazole with phosphodiesterase-3 (PDE-3) inhibitory action, vasorelaxant activity and low toxicity catalyzed by filamentous fungi biofilm in bioreactor was successfully developed. A maximum N-glycosyl yield of 68% was obtained with Cunninghamella echinulata ATCC 9244 biofilm in bioreactor with conditions of 25mgml(-1) of 1 in PDSM medium at 28°C for 96h. After extraction with ethyl acetate, the derivative was identified by Ultrahigh Resolution Mass Spectrometry and (1)H-(13)C HSQC/HMBC.


Assuntos
Biofilmes , Reatores Biológicos , Cunninghamella/metabolismo , Inibidores da Fosfodiesterase 3/farmacologia , Diester Fosfórico Hidrolases/metabolismo , Tetrazóis/farmacologia , Relação Dose-Resposta a Droga , Glicosilação , Estrutura Molecular , Inibidores da Fosfodiesterase 3/química , Inibidores da Fosfodiesterase 3/metabolismo , Relação Estrutura-Atividade , Tetrazóis/química , Tetrazóis/metabolismo
19.
J Adhes Dent ; 18(5): 375-386, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27695714

RESUMO

PURPOSE: To perform a systematic review of the clinical performance of a low polymerization shrinkage, siloranebased composite (SBC) compared with a methacrylate-based composite (MBC) in posterior restorations. MATERIALS AND METHODS: Electronic databases were searched: PubMed, Scopus, Bireme, Science Direct, Web of Science, ClinicalTrials.gov and OpenGrey. The search strategy included MeSH terms, synonyms and keywords with no language or date restrictions. Reference lists of eligible studies were cross checked in an attempt to identify additional studies. Based on the PICOS strategy, only randomized clinical trials (RCTs) were included. The risk of bias in the included studies was assessed and classified through the Cochrane Collaboration common scheme for bias. Two meta-analyses were performed using RevMan software, one with all 11 studies and another that included only studies with over 24 months of follow-up, for the main parameters analyzed. RESULTS: A total of 544 studies were identified. After removing duplicates and examinating titles and abstracts, 17 texts were selected and read in full. Six of them were excluded, so the final sample of this systematic review included 11 studies. Six of the 11 studies were classified as having a "low risk of bias" and five were "unclear". The heterogeneity (I²) in all parameters was not significant. The exclusion of studies with less than 24 months of follow- up did not change the final result of the meta-analysis: both SBC and MBC have satisfactory and statistically similar clinical performances. CONCLUSION: Low polymerization shrinkage is not the principal factor that determines the superiority of a resin.


Assuntos
Resinas Compostas , Restauração Dentária Permanente , Resinas de Silorano , Humanos , Metacrilatos , Ensaios Clínicos Controlados Aleatórios como Assunto
20.
Int J Mol Sci ; 17(5)2016 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-27196901

RESUMO

Tuberculosis (TB) is an infectious disease caused mainly by the bacillus Mycobacterium tuberculosis (Mtb), presenting 9.5 million new cases and 1.5 million deaths in 2014. The aim of this study was to evaluate a nanostructured lipid system (NLS) composed of 10% phase oil (cholesterol), 10% surfactant (soy phosphatidylcholine, sodium oleate), and Eumulgin(®) HRE 40 ([castor oil polyoxyl-40-hydrogenated] in a proportion of 3:6:8), and an 80% aqueous phase (phosphate buffer pH = 7.4) as a tactic to enhance the in vitro anti-Mtb activity of the copper(II) complexes [CuCl2(INH)2]·H2O (1), [Cu(NCS)2(INH)2]·5H2O (2) and [Cu(NCO)2(INH)2]·4H2O (3). The Cu(II) complex-loaded NLS displayed sizes ranging from 169.5 ± 0.7095 to 211.1 ± 0.8963 nm, polydispersity index (PDI) varying from 0.135 ± 0.0130 to 0.236 ± 0.00100, and zeta potential ranging from -0.00690 ± 0.0896 to -8.43 ± 1.63 mV. Rheological analysis showed that the formulations behave as non-Newtonian fluids of the pseudoplastic and viscoelastic type. Antimycobacterial activities of the free complexes and NLS-loaded complexes against Mtb H37Rv ATCC 27294 were evaluated by the REMA methodology, and the selectivity index (SI) was calculated using the cytotoxicity index (IC50) against Vero (ATCC(®) CCL-81), J774A.1 (ATCC(®) TIB-67), and MRC-5 (ATCC(®) CCL-171) cell lines. The data suggest that the incorporation of the complexes into NLS improved the inhibitory action against Mtb by 52-, 27-, and 4.7-fold and the SI values by 173-, 43-, and 7-fold for the compounds 1, 2 and 3, respectively. The incorporation of the complexes 1, 2 and 3 into the NLS also resulted in a significant decrease of toxicity towards an alternative model (Artemia salina L.). These findings suggest that the NLS may be considered as a platform for incorporation of metallic complexes aimed at the treatment of TB.


Assuntos
Antituberculosos/farmacologia , Complexos de Coordenação/farmacologia , Cobre/química , Mycobacterium tuberculosis/efeitos dos fármacos , Animais , Antituberculosos/química , Linhagem Celular , Chlorocebus aethiops , Complexos de Coordenação/química , Humanos , Lipídeos/química , Camundongos , Testes de Sensibilidade Microbiana/métodos , Nanoestruturas/química , Tamanho da Partícula , Tuberculose , Células Vero
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA