Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 21
Filtrar
1.
J Helminthol ; 84(2): 202-7, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19765323

RESUMO

Praziquantel (PZQ) is now widely used for the treatment of human schistosomiasis. However, in recent years, there has been a growing concern about the resistance of Schistosoma to PZQ. The mechanisms of PZQ action against Schistosoma and resistance of Schistosoma to PZQ are poorly understood. Here, we report differential susceptibilities to PZQ between male and female cercariae in the PZQ-susceptible and PZQ-resistant isolates of Schistosoma mansoni, using tail loss as a measurement of PZQ action. The miracidia were collected by hatching eggs collected from faeces of infected mice. Single-sex cercaria lines were made by infecting a single Biomphalaria glabrata snail with a single miracidium. The sex of each single-sex cercaria line was identified by a direct W1-specific polymerase chain reaction (PCR) technique. Single-sex cercariae of two isolates were exposed to four different concentrations of PZQ, respectively. The tail shedding of cercariae was observed under a dissecting microscope for five time points up to 100 min after adding PZQ. The results showed that male cercariae have higher tail-shedding rates than that of female cercariae when PZQ-susceptible isolates of S. mansoni are exposed to the same concentration of PZQ. But this phenomenon was not observed in the PZQ-resistant isolates. This sexual differential resistance phenomenon of S. mansoni suggests that resistance to PZQ is induced by decreasing the PZQ susceptibility of male worms. The experiment described here may also be useful for developing tests to detect PZQ resistance in the field.


Assuntos
Anti-Helmínticos/farmacologia , Resistência a Medicamentos , Praziquantel/farmacologia , Schistosoma mansoni/efeitos dos fármacos , Animais , Biomphalaria/parasitologia , Fezes/parasitologia , Feminino , Larva/efeitos dos fármacos , Masculino , Camundongos
2.
Eur Rev Med Pharmacol Sci ; 24(3): 1367-1377, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32096186

RESUMO

OBJECTIVE: The role of NEAT1 in cancers has been demonstrated. But the role of NEAT1 in cardiac hypertrophy still remains unknown. This study aimed to elucidate the specific function of long non-coding RNA (lncRNA) NEAT1 in cardiac hypertrophy and its underlying mechanism. PATIENTS AND METHODS: In this study, the in vivo and in vitro cardiac hypertrophy models were constructed by transverse aortic coarctation (TAC) procedure in rats and phenylephrine (PE) induction in primary cardiomyocytes, respectively. The expression levels of NEAT1, microRNA-19a-3p, SMYD2, and cardiac hypertrophic markers were detected by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). Cardiac hypertrophy was evaluated as calculating the surface area of hypertrophic cardiomyocyte by fluorescein isothiocyanate (FITC)-Phalloidin staining. Luciferase Reporter Gene Assay was conducted to detect the binding of NEAT1, SMYD2, and microRNA-19a-3p. RESULTS: The results showed that NEAT1 and SMYD2 were highly expressed in myocardium of rats with cardiac hypertrophy and PE-induced primary cardiomyocytes, whereas microRNA-19a-3p was lowly expressed. Besides, NEAT1 overexpression markedly upregulated levels of the cardiac hypertrophic markers. Moreover, FITC-Phalloidin staining also revealed hypertrophic cardiomyocytes overexpressing NEAT1. On the contrary, microRNA-19a-3p overexpression reduced the cardiomyocyte surface area and downregulated the levels of the cardiac hypertrophic markers. As luciferase reporter gene assay demonstrated, NEAT1 and SMYD2 could bind to microRNA-19a-3p. Finally, the gain-of-function experiments were designed to verify whether NEAT1 exerted its functions in cardiac hypertrophy by modulating SMYD2 and microRNA-19a-3p. Furthermore, both microRNA-19a-3p overexpression or SMYD2 knockdown could inhibit and reduce the cardiomyocyte surface area, and downregulate the levels of the cardiac hypertrophic markers. CONCLUSIONS: In summary, NEAT1 promotes the occurrence and progression of cardiac hypertrophy by upregulating SMYD2 by binding to microRNA-19a-3p.


Assuntos
Cardiomegalia/metabolismo , Histona-Lisina N-Metiltransferase/biossíntese , MicroRNAs/metabolismo , RNA Longo não Codificante/metabolismo , Animais , Animais Recém-Nascidos , Cardiomegalia/patologia , Células Cultivadas , Masculino , Ratos
3.
AJNR Am J Neuroradiol ; 41(8): 1397-1404, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32719091

RESUMO

BACKGROUND AND PURPOSE: Previous studies have shown that diffusion tensor imaging suggests a diffuse loss of white matter integrity in people with white matter hyperintensities or lacunes. The purpose of this study was to investigate whether the presence of cerebral microbleeds and their distribution are related to the integrity of white matter microstructures. MATERIALS AND METHODS: The study comprised 982 participants who underwent brain MR imaging to determine microbleed status. The cross-sectional relation between microbleeds and the microstructural integrity of the white matter was assessed by 2 statistical methods: a multilinear regression model based on the average DTI parameters of normal-appearing white matter and Tract-Based Spatial Statistics analysis, a tract-based voxelwise analysis. Fiber tractography was used to spatially describe the microstructural abnormalities along WM tracts containing a cerebral microbleed. RESULTS: The presence of cerebral microbleeds was associated with lower mean fractional anisotropy and higher mean diffusivity, axial diffusivity, and radial diffusivity, and the association remained when cardiovascular risk factors and cerebral small-vessel disease markers were further adjusted. Tract-Based Spatial Statistics analysis indicated strictly lobar cerebral microbleeds associated with lower fractional anisotropy, higher mean diffusivity, and higher radial diffusivity in the internal capsule and corpus callosum after adjusting other cerebral small-vessel disease markers, while only a few voxels remained associated with deep cerebral microbleeds. Diffusion abnormalities gradients along WM tracts containing a cerebral microbleed were not found in fiber tractography analysis. CONCLUSIONS: Cerebral microbleeds are associated with widely distributed changes in white matter, despite their focal appearance on SWI.


Assuntos
Hemorragia Cerebral/complicações , Hemorragia Cerebral/diagnóstico por imagem , Hemorragia Cerebral/patologia , Substância Branca/diagnóstico por imagem , Substância Branca/patologia , Idoso , Anisotropia , Doenças de Pequenos Vasos Cerebrais/complicações , Doenças de Pequenos Vasos Cerebrais/diagnóstico por imagem , Doenças de Pequenos Vasos Cerebrais/patologia , Estudos Transversais , Imagem de Tensor de Difusão/métodos , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade
4.
Eur Rev Med Pharmacol Sci ; 19(8): 1452-6, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25967721

RESUMO

OBJECTIVE: The objective of this study was to compare coronary artery bypass graft (CABG) surgery with non-extracorporeal vs. extracorporeal circulation. The study outcomes included operative time, number of graft vessels, pulmonary infection rates, and systemic inflammatory markers. PATIENTS AND METHODS: 96 patients received selective CABG, either with non-extracorporeal (study group; n = 48) or extracorporeal circulation (control group; n = 48). Operative time, pulmonary infection rates, and blood levels of inflammatory markers TNF-α, IL-6, and IL-8 before and 4, 24, and 48 hours after the surgery were quantified. Graft vessels were quantified using computed tomography. RESULTS: Operative time was significantly shorter in study group (4.58 ± 0.91 vs. 5.36 ± 1.12 hours in control group; p < 0.05). The number of graft vessels and pulmonary infection rates were comparable between both techniques. However, systemic inflammatory markers were significantly (p < 0.05) lower in study group at 4 and, partly, 24 hours after the surgery. CONCLUSIONS: Extracorporeal circulation prolongs operation and can aggravate systemic inflammatory response. Therefore, CABG with non-extracorporeal circulation offers more beneficial outcomes.


Assuntos
Ponte de Artéria Coronária/métodos , Circulação Extracorpórea/métodos , Adulto , Idoso , Biomarcadores/sangue , Ponte de Artéria Coronária/efeitos adversos , Circulação Extracorpórea/efeitos adversos , Feminino , Humanos , Mediadores da Inflamação/sangue , Interleucina-6/sangue , Interleucina-8/sangue , Masculino , Pessoa de Meia-Idade , Fator de Necrose Tumoral alfa/sangue
6.
AJNR Am J Neuroradiol ; 32(4): 709-13, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21349956

RESUMO

BACKGROUND AND PURPOSE: dVRS have been previously associated with aging and cerebrovascular diseases. However, little is known about their prevalence and topographic distribution in the general elderly population. MATERIALS AND METHODS: dVRS were evaluated by using high-resolution 3D MR imaging in 1826 subjects enrolled in the 3C-Dijon MR imaging study. On T1-weighted MR imaging, dVRS were detected according to 3D imaging criteria and rated by using 4-level severity scores based in the BG or in the WM. The number and anatomic location of large dVRS (≥3 mm) were recorded. RESULTS: dVRS were observed in the BG or WM in every subject. The severity of dVRS was significantly associated with higher age in both the BG and WM, whereas sex was related to the severity of dVRS only in the BG. Large dVRS were detected in 33.2% of participants. Status cribrosum was found in 1.3% of participants. dVRS were also highly prevalent within the hippocampus (44.5%) and hypothalamus (11.6%). CONCLUSIONS: dVRS are always detected in the BG or WM in elderly people, and large dVRS are also prevalent. The topographic distribution of dVRS is not uniform within the brain and may depend on anatomic or pathologic characteristics interacting with aging and sex.


Assuntos
Envelhecimento/patologia , Doença Cerebrovascular dos Gânglios da Base/patologia , Imageamento Tridimensional , Leucoencefalopatias/patologia , Imageamento por Ressonância Magnética/métodos , Idoso , Gânglios da Base/patologia , Doença Cerebrovascular dos Gânglios da Base/epidemiologia , Feminino , Hipocampo/patologia , Humanos , Hipotálamo/patologia , Leucoencefalopatias/epidemiologia , Imageamento por Ressonância Magnética/normas , Masculino , Prevalência , Valores de Referência , Fatores de Risco , Índice de Gravidade de Doença
16.
J Helminthol ; 76(4): 327-33, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12498638

RESUMO

The effect of treatment with praziquantel (PZQ) on the tegument of adult Schistosoma mansoni worms and on liver egg-granulomas has been examined in mice infected with PZQ-resistant and -susceptible parasite isolates. Two PZQ-resistant S. mansoni isolates, one selected by passage in the laboratory under drug pressure and one from Senegal established from eggs excreted by an uncured patient, were compared with PZQ-susceptible control isolates. Scanning electron microscopic observations on the tegument of Schistosoma adult worms treated in vivo with PZQ showed that more severe damage was inflicted by PZQ on susceptible worms than on drug-resistant worms. Observations on the pathology of Schistosoma egg-granulomas in the liver of infected mice after treatment with PZQ indicated that eggs from susceptible control isolates were more sensitive to PZQ than those from drug-resistant isolates.


Assuntos
Anti-Helmínticos/uso terapêutico , Praziquantel/uso terapêutico , Schistosoma mansoni/ultraestrutura , Esquistossomose mansoni/tratamento farmacológico , Animais , Resistência a Medicamentos , Feminino , Granuloma/parasitologia , Granuloma/patologia , Hepatopatias Parasitárias/parasitologia , Hepatopatias Parasitárias/patologia , Masculino , Camundongos , Microscopia Eletrônica de Varredura , Óvulo , Schistosoma mansoni/efeitos dos fármacos , Esquistossomose mansoni/parasitologia , Esquistossomose mansoni/patologia
17.
Nat Prod Rep ; 21(4): 478-89, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15282631

RESUMO

Recently, intense interest has focused on the antioxidant properties of natural products. In particular, Chinese herbal medicines (CHM) have become hot topics for life science researchers since many are reported to possess cardioprotective compounds, many of which remain to be identified. Indeed, the exact mechanisms by which CHM work remain unknown. Although many of these herbal remedies are undoubtedly efficacious, few have been scientifically investigated for their active chemical constituents and biological activities. We have previously reported higher activities of antioxidant defence enzymes such as superoxide dismutase, catalase, glutathione peroxidase and glutathione S-transferases in the liver of rats treated with the herb Salvia miltiorrhiza in a model of acute myocardial infarction. Using well established in vitro antioxidant assays employing 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) and diphenyl-l-picrylhydrazyl (DPPH) we have shown that in addition to elevating endogenous antioxidant enzyme activity, Salvia miltiorrhiza and other CHM traditionally used for cardiovascular disorders (such as Rhizoma ligustici, Herba leonuri, Radix achyranthis bidentatae, and Camellia sinensis) contain potent antioxidant moieties in addition to their phenolic constituents. Furthermore, these novel non-phenolic components are effective inhibitors of oxidative reactions mediated by the inflammatory oxidants, peroxynitrite,hypochlorous acid and hydroxyl radical as well as iron-dependent lipid peroxidation. In this review, we discuss the various antioxidant properties of CHM in the context of their biochemical mechanisms.


Assuntos
Antioxidantes , Medicamentos de Ervas Chinesas , Plantas Medicinais/química , Antioxidantes/química , Antioxidantes/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Estrutura Molecular
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA