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1.
Exp Brain Res ; 241(3): 851-864, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36757564

RESUMO

We demonstrated previously that the hypothalamic supraoptic nucleus (SON) undergoes an axonal sprouting response following a unilateral lesion of the hypothalamo-neurohypophysial tract in a 35-day-old rat to repopulate the partially denervated neural lobe (NL). However, no sprouting occurs following the same injury in a 125-day-old rat. We previously reported a significant increase in Thy-1 protein in the SON of a 125-day-old rat compared to a 35-day-old rat in the absence of injury. Thy-1 is a cell surface glycoprotein shown to inhibit axonal outgrowth following injury; however, we did not look at axotomy's effect on Thy-1 in the SON. Therefore, we sought to determine the integrin ligands that bind Thy-1 in the SON and how axotomy impacts Thy-1. Like what others have shown, the co-immunoprecipitation analysis demonstrated that Thy-1 interacts with αvß3 and αvß5 integrin dimers in the SON. We used western blot analysis to examine protein levels of Thy-1 and integrin subunits following injury in the 35- and 125-day-old rat SON and NL. Our results demonstrated that Thy-1 protein levels increase in the lesion SON in a 35-day-old rat. The quantitative dual-fluorescent analysis showed that the increase in Thy-1 in the lesion SON occurred in astrocytes. There was no change in Thy-1 or integrin protein levels following injury in the 125-day-old following injury. Furthermore, the axotomy significantly decreased Thy-1 protein levels in the NL of both 35- and 125-day-old rats. These results provide evidence that Thy-1 protein levels are injury dependent in the magnocellular neurosecretory system.


Assuntos
Núcleo Supraóptico , Ratos , Animais , Núcleo Supraóptico/metabolismo , Axotomia/métodos , Ratos Sprague-Dawley
2.
Artigo em Inglês | MEDLINE | ID: mdl-35162303

RESUMO

Objectives: Quang Nam province in the Centre of Vietnam has faced an outbreak of dengue hemorrhagic fever (DHF) in 2018. Although DHF is a recurrent disease in this area, no epidemiological and microbiological reports on dengue virus serotypes have been conducted mainly due to lack of facilities for such a kind of advanced surveillance. The aim of this study was to detect different dengue virus serotypes in patients' blood samples. Design and Methods: Suspected cases living in Quang Nam province (Vietnam) and presenting clinical and hematological signs of dengue hemorrhagic fever were included in the study. The screening was performed, and the results were compared by using two methodologies: RT real-time PCR (RT-rPCR) and the Dengue NS1 rapid test. Results: From December 2018 to February 2019, looking both at RT-rPCR [+] and NS1 [+] methodologies, a total of 488 patients were screened and 336 were positive for dengue virus detection (74 children and 262 adults); 273 of these patients (81.3%) underwent viral serotype identification as follows: 12.82% (35/273) D1 serotype, 17.95% (49/273) D2, 0.37% (1/273) D3, 68.50 (187/283) D4, and 0.37% (1/273) D2+D4 serotypes. The RT-rPCR outcomes showed higher sensitivity during the first three days of infection compared to NS1 (92.3% vs. 89.7%). The NS1 increased sensitivity after the first 3 days whilst the RT-rPCR decreased. Conclusions: Advanced surveillance with dengue virus serotypes identification, if performed routinely, may help to predict and prevent further DHF epidemics based on the exposure of the different serotypes during different periods that lead to the intensification of disease severity as a consequence of antibody-dependent enhancement (ADE).


Assuntos
Vírus da Dengue , Dengue , Adulto , Anticorpos Antivirais , Criança , Dengue/diagnóstico , Vírus da Dengue/genética , Surtos de Doenças , Humanos , Sorogrupo , Vietnã/epidemiologia
3.
Sci Rep ; 7(1): 8692, 2017 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-28821752

RESUMO

Nitric oxide (NO) has been known to promote physiological angiogenesis to treat peripheral arterial diseases (PAD) by increasing the vascular endothelial growth factor (VEGF) level in endothelial cells (ECs) and preventing platelet adherence and leukocyte chemotaxis. However, the ongoing ischemic event during peripheral ischemia produces superoxide and diminishes the NO bioavailability by forming toxic peroxynitrite anion. Here we disclose an efficacious hybrid molecule 4-(5-Amino-1,2,3-oxadiazol-3-yl)-2,2,6,6-tetramethyl-1-piperidinol (SA-2) containing both antioxidant and NO donor functionalities that provide a therapeutic level of NO necessary to promote angiogenesis and to protect ECs against hydrogen peroxide-induced oxidative stress. Compound SA-2 scavenged reactive oxygen species, inhibited proliferation and migration of smooth muscle cells (SMCs) and promoted the tube formation from ECs. Copolymer poly(lactic-co-glycolic acid) (PLGA) nanoparticles loaded with SA-2 provided a sustained release of NO over days, improved aqueous stability in serum, protected ECs against oxidative stress, and enhanced angiogenesis under stress conditions as compared to that of the control in the in vitro matrigel tube formation assay. These results indicated the potential use of SA-2 nanoparticles as an alternative therapy to treat PAD.


Assuntos
Doadores de Óxido Nítrico/uso terapêutico , Doença Arterial Periférica/tratamento farmacológico , Vasos Sanguíneos/efeitos dos fármacos , Vasos Sanguíneos/metabolismo , Hipóxia Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Miócitos de Músculo Liso/efeitos dos fármacos , Miócitos de Músculo Liso/metabolismo , Nanopartículas/química , Nanopartículas/ultraestrutura , Neovascularização Fisiológica/efeitos dos fármacos , Doadores de Óxido Nítrico/química , Doadores de Óxido Nítrico/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Doença Arterial Periférica/patologia
4.
Health Promot Int ; 31(1): 133-43, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25381163

RESUMO

Men who have sex with men (MSM) are one of the largest HIV risk groups in Viet Nam and have been understudied. Sexual concurrency and multiple sex partnerships may contribute to high HIV incidence among MSM in Viet Nam. Limited information is available on concurrency and multiple sexual partnerships among MSM in Viet Nam or on the extent to which this population engages in concurrent and multiple unprotected anal intercourse. Data are from a self-administered Internet-based survey of Vietnamese MSM aged 18 years or older, having sex with male partner(s) in the last 12 months and recruited from social networking MSM-specific websites in Viet Nam. Multiple partnerships and concurrency were measured using the UNAIDS-recommended sexual partner matrix, a key component in the questionnaire. Concurrent and multiple sexual partnerships were analyzed at the individual level. Logistic regression analyses were conducted to assess the demographic characteristics and behaviors associated with multiple sexual partnerships. A total of 1695 MSM reported on multiple sexual partnerships; 69.5% indicated multiple sexual partnerships in the last 6 months. A total of 257 MSM reported on concurrent sexual partnerships, with 51.0% reporting penetrative sex with concurrent partners in the last 6 months. Respondents were more likely to engage in multiple sexual partnerships if they were no longer a student, consumed alcohol before and/or during sex, used the Internet to meet casual sex partners and had never participated in a behavioral HIV intervention. Multiple sexual partnerships in the previous 6 months were common among MSM surveyed, as was sexual concurrency. High levels of multiple and concurrent sexual partnerships may be catalyzing the transmission of HIV among MSM in Viet Nam. Given the high prevalence of this high-risk sexual behavior, our findings underscore the urgent need for targeted prevention efforts, focusing on the reduction of multiple and concurrent sexual partners among this key population.


Assuntos
Homossexualidade Masculina , Parceiros Sexuais , Mídias Sociais , Adolescente , Adulto , Estudos Transversais , Infecções por HIV/prevenção & controle , Infecções por HIV/transmissão , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Comportamento Sexual , Inquéritos e Questionários , Vietnã , Adulto Jovem
5.
Phys Rev Lett ; 107(13): 136604, 2011 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-22026883

RESUMO

The electron spin dynamics in (111)-oriented GaAs/AlGaAs quantum wells is studied by time-resolved photoluminescence spectroscopy. By applying an external electric field of 50 kV/cm a two-order of magnitude increase of the spin relaxation time can be observed reaching values larger than 30 ns; this is a consequence of the electric field tuning of the spin-orbit conduction band splitting which can almost vanish when the Rashba term compensates exactly the Dresselhaus one. The measurements under a transverse magnetic field demonstrate that the electron spin relaxation time for the three space directions can be tuned simultaneously with the applied electric field.

6.
Eur J Pharm Sci ; 35(1-2): 42-51, 2008 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-18617002

RESUMO

The purpose of this study was to use Artificial Neural Networks (ANNs) in identifying factors, in addition to surfactant and internal phase content, that influence the particle size of nanoemulsions. The phase diagram and rheometric characteristics of a nanoemulsion system containing polysorbate 80, ethanol, medium chain triglycerides and normal saline loaded with budesonide were investigated. The particle size of samples of various compositions prepared using different rates and amounts of applied energy was measured. Data, divided into training, test and validation sets, were modelled by ANNs. The developed model was assessed and found to be of high quality. The model was then used to explore the effect of composition and processing factors on particle size of the nanoemulsion preparation. The study demonstrates the potential of ANNs in identifying critical parameters controlling preparation for this system, with the total amount of applied energy during preparation found to be the dominant factor in controlling the final particle size.


Assuntos
Emulsões , Nanopartículas , Algoritmos , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/química , Budesonida/administração & dosagem , Budesonida/química , Interpretação Estatística de Dados , Etanol/química , Excipientes , Indicadores e Reagentes , Redes Neurais de Computação , Tamanho da Partícula , Polissorbatos , Reprodutibilidade dos Testes , Software , Solventes , Triglicerídeos/administração & dosagem , Triglicerídeos/química
7.
Int J Pharm ; 351(1-2): 194-200, 2008 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-18053658

RESUMO

This study has investigated and compared genetic programming (GP) - a method of automatically generating equations that describe the cause-and-effect relationships in a system - and statistical methods for modelling two controlled release formulations--a matrix tablet and microspheres. With the improved GP models exhibiting comparable predictive power, as well as simpler equations in some cases, the results obtained indicate that GP can be considered as an effective and efficient method for modelling controlled release formulations.


Assuntos
Química Farmacêutica/métodos , Simulação por Computador , Modelos Teóricos , Preparações Farmacêuticas/química , Preparações de Ação Retardada , Previsões , Microesferas , Modelos Estatísticos , Reprodutibilidade dos Testes , Solubilidade , Comprimidos
8.
Rev Epidemiol Sante Publique ; 55(2): 107-12, 2007 Apr.
Artigo em Francês | MEDLINE | ID: mdl-17442516

RESUMO

BACKGROUND: The transmission of hepatitis C virus (HCV) is strongly associated with blood transfusion and drug abuse. However, in about a third of HCV-infected subjects, the risk factors are not clearly identified though some cases are likely to be healthcare associated. In an Asian country such as Vietnam, invasive procedures used for traditional and beauty care could be potential risk factors. The aim of the present study was to identify the risk factors of HCV infection in a population sample in Ho Chi Minh City. METHOD: A case-control study matched by gender and age was performed among blood adults donors at the Centre of hematological diseases and blood transfusion. Cases were defined as blood donors with HCV-positive Elisa. Controls were selected at random among ELISA HCV-negative donors. A standardized questionnaire was used to collect data focusing on invasive medical procedures, beauty care and on invasive procedures related to traditional medicine. RESULT: Among the 80 cases and 240 controls, the independent predictors of anti-HCV positivity using a stepwise logistic regression were: blood transfusion, intravenous drug abuse, acupuncture, ventoused scarification and practice of scarification (adjusted odds ratio and IC95%: 3.8 [1.1-13.1], 3.5 [1.7-7.3], 5.4 [2.3-12.7], 5.4 [2.5-11.7], 6.6 [1.6-26.4] respectively). The other risk factors such as past hospitalization surgery, tattooing, being a healthcare worker, or practising tattooing or piercing were not associated with HCV infection. CONCLUSION: To be exposed to ventoused scarifications or acupuncture are risk factors for the transmission of HCV in Vietnam. A wide information campaign on hygiene practices for general population as well as the practitioners is needed to ensure safer health cares in traditional medicine.


Assuntos
Terapia por Acupuntura/efeitos adversos , Hepatite C/transmissão , Medicina Tradicional do Leste Asiático , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Reação Transfusional , Vietnã
9.
Proc Natl Acad Sci U S A ; 98(20): 11485-90, 2001 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-11572994

RESUMO

We have searched for genes predisposing to bipolar disorder (BP) by studying individuals with the most extreme form of the affected phenotype, BP-I, ascertained from the genetically isolated population of the Central Valley of Costa Rica (CVCR). The results of a previous linkage analysis on two extended CVCR BP-I pedigrees, CR001 and CR004, and of linkage disequilibrium (LD) analyses of a CVCR population sample of BP-I patients implicated a candidate region on 18p11.3. We further investigated this region by creating a physical map and developing 4 new microsatellite and 26 single-nucleotide polymorphism markers for typing in the pedigree and population samples. We report the results of fine-scale association analyses in the population sample, as well as evaluation of haplotypes in pedigree CR001. Our results suggest a candidate region containing six genes but also highlight the complexities of LD mapping of common disorders.


Assuntos
Transtorno Bipolar/genética , Mapeamento Cromossômico , Cromossomos Humanos Par 18 , Transtornos do Humor/genética , Alelos , Costa Rica , Feminino , Marcadores Genéticos , Predisposição Genética para Doença , Humanos , Masculino , Repetições de Microssatélites/genética , Linhagem
10.
Hum Mutat ; 18(2): 120-31, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11462236

RESUMO

Carboxypeptidase E (CPE) is involved in the biosynthesis of peptide hormones and neurotransmitters, including insulin. One of the features of type 2 diabetes mellitus (T2DM) is an elevation in the proinsulin level and/or proinsulin/insulin molar ratio, suggesting that mutations in proinsulin processing enzymes may contribute to the development of T2DM. We scanned CPE for mutations in a collection of Ashkenazi T2DM families and identified five novel single nucleotide polymorphisms (SNPs). An SNP in the 283(rd) codon, c.847C>T, changes arginine to tryptophan (R283W). The residue Arg283 is conserved among CPE orthologs as well as most enzymatically active metallocarboxypeptidases. Of the 272 Ashkenazi T2DM pedigrees screened, we found four families segregating R283W. Within these four families, patients who inherited one copy of this variant had much earlier age of onset for T2DM. The R283W CPE protein cleaves peptide substrates with substantially lower efficiencies and is less stable at elevated temperature. In addition, the R283W CPE variant has a narrower pH optimum and is much less active at pH 6.0-6.5, indicating that the R283W CPE variant would be substantially less active than wild type CPE in the trans-Golgi network and immature secretory vesicles where the enzyme functions in vivo. To summarize, we uncovered a rare non-conservative missense mutation in CPE and demonstrated that the mutant protein has altered enzymatic properties. We predict that this mutant could cause hyperproinsulinism and diabetes in the homozygous state.


Assuntos
Carboxipeptidases/genética , Carboxipeptidases/metabolismo , Mutação de Sentido Incorreto/genética , Polimorfismo de Nucleotídeo Único/genética , Regiões 5' não Traduzidas/genética , Sequência de Aminoácidos , Carboxipeptidase H , Carboxipeptidases/química , Linhagem Celular , Cromatografia Líquida de Alta Pressão , Análise Mutacional de DNA , Estabilidade Enzimática , Éxons/genética , Feminino , Testes Genéticos , Heterozigoto , Humanos , Concentração de Íons de Hidrogênio , Judeus/genética , Cinética , Masculino , Dados de Sequência Molecular , Linhagem , Regiões Promotoras Genéticas/genética , Alinhamento de Sequência , Temperatura , População Branca/genética
12.
AIDS Res Hum Retroviruses ; 12(7): 629-33, 1996 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-8743088

RESUMO

PIP: Samples of peripheral blood mononuclear cells from 50 HIV-1-infected individuals in South Vietnam were analyzed to determine with which HIV-1 subtype the subjects were infected. Participants were from Ho Chi Minh city and five surrounding provinces; 16 samples from female prostitutes, 32 from IV drug users, and one each from a man and woman not in any HIV risk group. 32 individuals were therefore most likely infected by IV drug use and the rest through sexual contacts. PCR amplification and heteroduplex mobility assay found all but one case to be infected with HIV-1 subtype E. The only nonsubtype E infection was HIV-1 subtype B in a woman sexually infected by her seropositive partner who was most likely exposed to the virus in Europe. HIV-1 subtype E strongly predominates in South Vietnam. The homogeneous geographic distribution of subtype E suggests the recent introduction of the virus into the country. A Thai origin can be considered given the genetic relationship between the Thai and Vietnamese subtypes E. It may be assumed that subtype E infections of Vietnamese prostitutes are related to the progressive entry and spread of HIV-1 subtype E from Thailand to Cambodia and then to southern Vietnam.^ieng


Assuntos
Infecções por HIV/virologia , HIV-1/classificação , Sequência de Aminoácidos , Sequência de Bases , DNA Viral , Feminino , Proteína gp120 do Envelope de HIV/genética , HIV-1/genética , Humanos , Dados de Sequência Molecular , Filogenia , Projetos Piloto , Homologia de Sequência de Aminoácidos , Vietnã
14.
Angiology ; 32(10): 705-10, 1981 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7034591

RESUMO

A double-blind study was performed on 40 physically trained patients with stage II peripheral arterial insufficiency. Daily doses of 450 mg buflomedil were administered for 90 days and eventual improvements were compared to the effects of pentoxifylline given in daily doses of 300 mg. After treatment with buflomedil and also with pentoxifylline, significant increases were achieved in walking distances during these tests, the increase was not significant. Nor uniform findings were noted in oscillograms and in ultrasonic Doppler investigations.


Assuntos
Arteriopatias Oclusivas/tratamento farmacológico , Pentoxifilina/uso terapêutico , Pirrolidinas/uso terapêutico , Teobromina/análogos & derivados , Adulto , Idoso , Análise de Variância , Arteriopatias Oclusivas/diagnóstico , Ensaios Clínicos como Assunto , Método Duplo-Cego , Humanos , Pessoa de Meia-Idade , Oscilometria , Esforço Físico/efeitos dos fármacos , Ultrassonografia
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