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1.
Heliyon ; 10(10): e31233, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38803938

RESUMO

With the development of Computer Vision, we can effectively and accurately identify trees, fruit or object images. But to build a high-performance image dataset for tree identification problems in Agriculture is a challenge. Realizing that Vietnam is a country with strong agriculture with many tropical fruits grown widely such as Dragon fruit, Mangosteen, Mango, Orange, Lychee, Longan … We chose the Dragon Fruit tree for the data set. of my proposed images, all images will be collected using the close-up method, including tasks such as taking photos of Dragon Fruit trees from many angles and in different conditions (weather, temperature, light, …). In this article, we want to improve the data quality of the collected images so we have applied image processing techniques such as noise filtering (using Gaussian filter), image quality enhancement (image rotation), flip the image, zoom out, zoom in, etc.). From the collected Dragon Fruit tree data set, we will propose to use the Faster R-CNN model for this data set to build a tree and Dragon Fruit identification system.

2.
J Environ Manage ; 354: 120497, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38417365

RESUMO

By identifying Earth heritage sites, UNESCO Global Geoparks (UGGps) have promoted geo-tourism and regional economic prosperity. However, commercial and tourism development has altered the natural contexts of these geoparks, diminishing their initial value. Before implementing land use policies, spatial landscape parameters should be monitored in multiple dimensions and in real time. This study aims to develop Bilateral Segmentation Network (BiSeNet) models employing an upgraded U-structured neural network in order to monitor land use/cover changes and landscape indicators in a Vietnamese UGGp. This network has proven effective at preserving input image data and restricting the loss of spatial information in decoding data. To demonstrate the utility of deep learning, eight trained BiSeNet models were evaluated against Maximum Likelihood, Support Vector Machine, and Random Forest. The trained BSN-Nadam model (128x128), with a precision of 94% and an information loss of 0.1, can become a valuable instrument for analyzing and monitoring monthly changes in land uses/covers once tourism activities have been rapidly expanded. Three tourist routes and 41 locations in the Dak Nong UGGp were monitored for 30 years using three landscape indices: Disjunct Core Area Density (DCAD), Total Edge Contrast Index (TECI), Shannon's Diversity Index (SHDI), based on the results of the model. As a result, 18 identified geo-sites in the Daknong Geopark have been influenced significantly by agricultural and tourist activities since 2010, making these sites less uniform and unsustainable management. It promptly alerts UNESCO management to the deterioration of geological sites caused by urbanization and tourist development.


Assuntos
Aprendizado Profundo , UNESCO , Monitoramento Ambiental/métodos , Urbanização , Agricultura , Conservação dos Recursos Naturais
3.
Lancet Glob Health ; 12(2): e226-e234, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38245113

RESUMO

BACKGROUND: Non-sputum-based triage tests for tuberculosis are a priority for ending tuberculosis. We aimed to evaluate the diagnostic accuracy of the late-prototype Xpert MTB Host Response (Xpert HR) blood-based assay. METHODS: We conducted a prospective diagnostic accuracy study among outpatients with presumed tuberculosis in outpatient clinics in Viet Nam, India, the Philippines, Uganda, and South Africa. Eligible participants were aged 18 years or older and reported cough lasting at least 2 weeks. We excluded those receiving tuberculosis treatment in the preceding 12 months and those who were unwilling to consent. Xpert HR was performed on capillary or venous blood. Reference standard testing included sputum Xpert MTB/RIF Ultra and mycobacterial culture. We performed receiver operating characteristic (ROC) analysis to identify the optimal cutoff value for the Xpert HR to achieve the target sensitivity of 90% or more while maximising specificity, then calculated diagnostic accuracy using this cutoff value. This study was prospectively registered with ClinicalTrials.gov, NCT04923958. FINDINGS: Between July 13, 2021, and Aug 15, 2022, 2046 adults with at least 2 weeks of cough were identified, of whom 1499 adults (686 [45·8%] females and 813 [54·2%] males) had valid Xpert HR and reference standard results. 329 (21·9%) had microbiologically confirmed tuberculosis. Xpert HR had an area under the ROC curve of 0·89 (95% CI 0·86-0·91). The optimal cutoff value was less than or equal to -1·25, giving a sensitivity of 90·3% (95% CI 86·5-93·3; 297 of 329) and a specificity of 62·6% (95% CI 59·7-65·3; 732 of 1170). Sensitivity was similar across countries, by sex, and by subgroups, although specificity was lower in people living with HIV (45·1%, 95% CI 37·8-52·6) than in those not living with HIV (65·9%, 62·8-68·8; difference of 20·8%, 95% CI 13·0-28·6; p<0·0001). Xpert HR had high negative predictive value (95·8%, 95% CI 94·1-97·1), but positive predictive value was only 40·1% (95% CI 36·8-44·1). Using the Xpert HR as a triage test would have reduced confirmatory sputum testing by 57·3% (95% CI 54·2-60·4). INTERPRETATION: Xpert HR did not meet WHO minimum specificity targets for a non-sputum-based triage test for pulmonary tuberculosis. Despite promise as a rule-out test that could reduce confirmatory sputum testing, further cost-effectiveness modelling and data on acceptability and usability are needed to inform policy recommendations. FUNDING: National Institute of Allergy and Infectious Diseases of the US National Institutes of Health. TRANSLATIONS: For the Vietnamese and Tagalog translations of the abstract see Supplementary Materials section.


Assuntos
Soropositividade para HIV , Mycobacterium tuberculosis , Tuberculose Pulmonar , Adulto , Feminino , Humanos , Masculino , Tosse , Índia , Filipinas , Estudos Prospectivos , Sensibilidade e Especificidade , África do Sul , Escarro/microbiologia , Triagem , Tuberculose Pulmonar/diagnóstico , Uganda , Vietnã
4.
Nutrients ; 14(3)2022 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-35276914

RESUMO

Lactococcus lactis strain Plasma (LC-Plasma) is reported to have anti-viral effects via direct activation of plasmacytoid dendritic cells, which upregulate the production of type I and III interferons. A randomized, placebo-controlled, double-blind, parallel group study was designed for elementary schoolchildren, grades 1 to 3, in Vietnam. LC-Plasma or a control were administered to schoolchildren as a beverage (1.0 × 1011 count LC-Plasma/day/person). The primary endpoint was to determine the efficacy of LC-Plasma in reducing the cumulative days absent from school due to upper respiratory disease (URID) and gastrointestinal disease (GID), and the secondary endpoint was to evaluate the potency of LC-Plasma on URID/GID symptoms and general well-being scores. LC-Plasma intake significantly reduced the cumulative days absent from school due to URID/GID (Odds ratio (OR) = 0.57, p = 0.004) and URID alone (OR = 0.56, p = 0.005); LC-Plasma also significantly reduced the number of cumulative fever positive days during the first 4 weeks of intervention (OR = 0.58, p = 0.001) and cumulative days with diarrhea during the last 4 weeks of the intervention period (OR = 0.78, p = 0.01). The number of positive general wellbeing days was significantly improved in the LC-Plasma group compared with the control throughout the intervention period (OR = 0.93, 0.93, p = 0.03, 0.04 in the first and last 4 weeks of the intervention, respectively). These data suggest that LC-Plasma seems to improve the health condition of elementary schoolchildren and reduces school absenteeism due to infectious disease, especially URID.


Assuntos
Doenças Transmissíveis , Lactococcus lactis , Povo Asiático , Criança , Método Duplo-Cego , Humanos , Lactococcus lactis/fisiologia , Vietnã/epidemiologia
5.
Med Arch ; 75(2): 112-115, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34219870

RESUMO

BACKGROUND: Helicobacter pylori infections induce chronic gastric mucosal inflammation and peptic ulcer disease, and eradication is recommended. OBJECTIVE: To investigate antibiotic resistance and H. pylori eradication rates in children with gastroduodenal ulcers in Vietnam. METHODS: We performed gastroduodenal endoscopies, H. pylori cultures, and antimicrobial susceptibility testing (clarithromycin, amoxicillin, metronidazole, tetracycline, and levofloxacin) In children with gastroduodenal ulcers at Children's Hospital 2 from November 1, 2019, to June 30, 2020. RESULTS: A total of 76 participants were studied, with an average age of 9.3 ± 2.8 years (range: 4-15 years), including 52.6% males and 47.4% females. The antibiotic resistance rates were clarithromycin, 92.1%; amoxicillin, 50%; levofloxacin, 31.6%; metronidazole, 14.5%; and tetracycline, 0%. The successful eradication rate was 44.7%. Bismuth increased the eradication rate by 3.69-fold that without bismuth (p = 0.030). The eradication rate of levofloxacin was high (100%, p = 0.038) compared with other antibiotics. The effectiveness of high-dose amoxicillin in cases with >50% H. pylori amoxicillin resistance was only 32.6% (p = 0.015). CONCLUSION: Increased antibiotic resistance among H. pylori resulted in decreased eradication efficacy, which was 44.7% in this study. Drug combinations, such as levofloxacin and bismuth, can increase the H. pylori eradication efficacy in children.


Assuntos
Antibacterianos/uso terapêutico , Farmacorresistência Bacteriana/efeitos dos fármacos , Quimioterapia Combinada , Infecções por Helicobacter/complicações , Infecções por Helicobacter/tratamento farmacológico , Úlcera Péptica/tratamento farmacológico , Úlcera Péptica/etiologia , Adolescente , Amoxicilina/uso terapêutico , Povo Asiático , Criança , Pré-Escolar , Claritromicina/uso terapêutico , Erradicação de Doenças/métodos , Feminino , Humanos , Levofloxacino/uso terapêutico , Masculino , Metronidazol/uso terapêutico , Testes de Sensibilidade Microbiana , Tetraciclina/uso terapêutico
6.
Pathog Dis ; 73(5)2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25933611

RESUMO

Ebola virus disease (EVD) is one of the most lethal transmissible infections characterized by a high fatality rate, and a treatment has not been developed yet. Recently, it has been shown that cationic amphiphiles, among them the antiarrhythmic drug amiodarone, inhibit filovirus infection. In the present work, we investigated how amiodarone interferes with Ebola virus infection. Wild-type Sudan ebolavirus and recombinant vesicular stomatitis virus, pseudotyped with the Zaire ebolavirus glycoprotein, were used to gain further insight into the ability of amiodarone to affect Ebola virus infection. We show that amiodarone decreases Ebola virus infection at concentrations close to those found in the sera of patients treated for arrhythmias. The drug acts by interfering with the fusion of the viral envelope with the endosomal membrane. We also show that MDEA, the main amiodarone metabolite, contributes to the antiviral activity. Finally, studies with amiodarone analogues indicate that the antiviral activity is correlated with drug ability to accumulate into and interfere with the endocytic pathway. Considering that it is well tolerated, especially in the acute setting, amiodarone appears to deserve consideration for clinical use in EVD.


Assuntos
3,4-Metilenodioxianfetamina/análogos & derivados , Amiodarona/farmacologia , Antivirais/farmacologia , Ebolavirus/efeitos dos fármacos , Ebolavirus/fisiologia , Internalização do Vírus/efeitos dos fármacos , 3,4-Metilenodioxianfetamina/farmacologia , Animais , Linhagem Celular , Humanos , Testes de Sensibilidade Microbiana
7.
Arch Sex Behav ; 44(2): 349-56, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25617010

RESUMO

This article examined the associations between three forms of homosexuality-related stigma (enacted, perceived, and internalized homosexual stigmas) with risky sexual behaviors, and to describe the mechanisms of these associations, among men who have sex with men (MSM) in Hanoi, Vietnam. We used respondent-driven sampling (RDS) to recruit 451 MSM into a cross-sectional study conducted from August 2010 to January 2011. Data were adjusted for recruitment patterns due to the RDS approach; logistic regression and path analyses were performed. Participants were young and single; most had attended at least some college. Nine out of ten participants engaged in sexual behaviors at moderate to high risk levels. Compared to those who had no enacted homosexual stigma, men having low and high levels of enacted homosexual stigma, respectively, were 2.23 times (95 % CI 1.35-3.69) and 2.20 times (95 % CI 1.04-4.76) more likely to engage in high levels of sexual risk behaviors. In addition, there was an indirect effect of perceived homosexual stigma and internalized homosexual stigma on sexual risk behaviors through depression and drug and alcohol use. Our study provides valuable information to our understanding of homosexual stigma in Vietnam, highlighting the need for provision of coping skills against stigma to the gay community and addressing drinking and drug use among MSM, to improve the current HIV prevention interventions in Vietnam.


Assuntos
Homossexualidade Masculina , Assunção de Riscos , Estigma Social , Sexo sem Proteção/psicologia , Adaptação Psicológica , Adolescente , Adulto , Estudos Transversais , Depressão , Infecções por HIV/prevenção & controle , Humanos , Modelos Logísticos , Masculino , Risco , Vietnã , Adulto Jovem
8.
J Sex Transm Dis ; 2013: 174506, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-26316952

RESUMO

Objective. To develop and assess a homosexuality-related stigma scale among men who have sex with men (MSM) in Hanoi, Vietnam. Methods. We conducted a cross-sectional study using respondent-driven sampling in Hanoi, Vietnam, in 2011. We used a cross-validation approach. Factor analysis was performed, and interitem correlation matrices were constructed to identify the latent factor structures, examine the goodness of fit, and assess convergent and discriminant validity of the determined scales. Internal consistency checks were performed in split samples and whole sample, and separately for each determined factor. Results. The findings were consistent in split samples. Three homosexuality-related stigma factors were identified: enacted homosexual stigma, perceived homosexual stigma, and internalized homosexual stigma. The fit indices of the confirmatory factor analysis in both split samples supported the hypothesized three-factor structures (in subsamples A and B: χ (2)/degrees of freedom ratio = 1.77 and 1.59, nonnormed fit index = 0.92 and 0.94, comparative fit index = 0.93 and 0.95, and the root mean square of approximation = 0.06 and 0.05, resp.). The interitem correlation supported the convergent and discriminant validity of the scales. The reliability of the three scales indicated good consistency (Cronbach's alpha: 0.79-0.84) across split samples and for the whole data. Conclusion. Our scales have good psychometric properties for measuring homosexuality-related stigma. These comprehensive and practical tools are crucial not only to assess stigma against MSM and its consequence, but also to guide the development of interventions targeting MSM, as well as to evaluate the efficacy of existing stigma reduction efforts in Vietnam and other countries with similar settings.

9.
Amino Acids ; 43(3): 1287-96, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22189890

RESUMO

Changes in plasma aromatic amino acids (AAA = phenylalanine, tryptophan, tyrosine) and branched chain amino acids (BCAA = isoleucine, leucine, valine) levels possibly influencing intracranial pressure (ICP) and cerebral oxygen consumption (SjvO(2)) were investigated in 19 sedated patients up to 14 days following severe traumatic brain injury (TBI). Compared to 44 healthy volunteers, jugular venous plasma BCAA were significantly decreased by 35% (p < 0.001) while AAA were markedly increased in TBI patients by 19% (p < 0.001). The BCAA to AAA ratio was significantly decreased by 55% (p < 0.001) which persisted during the entire study period. Elevated plasma phenylalanine was associated with decreased ICP and increased SjvO(2), while higher plasma isoleucine and leucine levels were associated with increased ICP and higher plasma leucine and valine were linked to decreased SjvO(2). The amount of enterally administered amino acids was associated with significantly increased plasma levels with the exception of phenylalanine. Contrary to the initial assumption that elevated AAA and decreased BCAA levels are detrimental, increased plasma phenylalanine levels were associated with beneficial signs in terms of decreased ICP and reduced cerebral oxygen consumption reflected by increased SjvO(2); concomitantly, elevated plasma isoleucine and leucine levels were associated with increased ICP while leucine and valine were associated with decreased SjvO(2) following severe TBI, respectively. The impact of enteral nutrition on this observed pattern must be examined prospectively to determine if higher amounts of phenylalanine should be administered to promote beneficial effects on brain metabolism and if normalization of plasma BCAA levels is without cerebral side effects.


Assuntos
Aminoácidos Aromáticos/sangue , Aminoácidos de Cadeia Ramificada/sangue , Lesões Encefálicas/sangue , Pressão Intracraniana , Oxigênio/sangue , Adolescente , Adulto , Biomarcadores/sangue , Glicemia , Lesões Encefálicas/patologia , Lesões Encefálicas/fisiopatologia , Estudos de Casos e Controles , Feminino , Humanos , Veias Jugulares/fisiopatologia , Masculino , Pessoa de Meia-Idade , Adulto Jovem
10.
Minerva Anestesiol ; 77(9): 870-6, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21878868

RESUMO

BACKGROUND: Cerebral metabolic impairment is feared to induce secondary brain damage following traumatic brain injury (TBI). The present study was designed to assess the temporal profile of calculated arterio- jugular venous differences in glutamate (AJVDglu) and SjvO(2) in patients subjected to continuous pharmacologic coma. Metabolic impairment was assumed to be reflected by increased jugular venous glutamate levels and decreased jugular venous oxygen saturation (SjvO(2)). METHODS: Arterial and jugular venous blood was drawn once daily for up to 14 days from 14 patients to assess the temporal profile. Plasma glutamate was measured by high performance liquid chromatography. SjvO(2), lactate and paCO(2) were determined in routine blood gas analysis. Calculated AJVD indirectly reflects cerebral uptake (positive values) or cerebral release (negative values). RESULTS: During pharmacologic coma an increase in ICP approaching 20 mmHg was associated with significantly reduced paCO(2) (4.7 ± 0.5 kPa; mean ± standard deviation), markedly decreased SjvO(2) (66.0 ± 4.2%) without reaching ischemic values, and a trend to more negative AJVDglu values (-6.0 ± 14.3 µmol/L), suggesting cerebral glutamate release. Arterio- jugular venous lactate difference (AJVDlac) remained unchanged. CONCLUSION: During pharmacologic coma increased ICP was associated with significantly decreased SjvO(2) which coincided only with a trend to increased cerebral glutamate release. Calculated AJVDglu appears to be inferior in unmasking altered brain metabolism compared to SjvO(2) whenever ICP is increased.


Assuntos
Artérias/fisiologia , Lesões Encefálicas/sangue , Ácido Glutâmico/sangue , Veias Jugulares/fisiologia , Oxigênio/sangue , Adolescente , Adulto , Anestesia , Temperatura Corporal/fisiologia , Dióxido de Carbono/sangue , Cromatografia Líquida de Alta Pressão , Cuidados Críticos , Feminino , Humanos , Hipnóticos e Sedativos/uso terapêutico , Pressão Intracraniana , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Adulto Jovem
11.
Biochem Pharmacol ; 82(9): 1234-49, 2011 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-21878321

RESUMO

Patients treated with amiodarone accumulate lysobisphosphatidic acid (LBPA), also known as bis(monoacylglycero)phosphate, in airway secretions and develop in different tissues vacuoles and inclusion bodies thought to originate from endosomes. To clarify the origin of these changes, we studied in vitro the effects of amiodarone on endosomal activities like transferrin recycling, Shiga toxin processing, ESCRT-dependent lentivirus budding, fluid phase endocytosis, proteolysis and exosome secretion. Furthermore, since the accumulation of LBPA might point to a broader disturbance in lipid homeostasis, we studied the effect of amiodarone on the distribution of LBPA, unesterified cholesterol, sphingomyelin and glycosphyngolipids. Amiodarone analogues were also studied, including the recently developed derivative dronedarone. We found that amiodarone does not affect early endosomal activities, like transferrin recycling, Shiga toxin processing and lentivirus budding. Amiodarone, instead, interferes with late compartments of the endocytic pathway, blocking the progression of fluid phase endocytosis and causing fusion of organelles, collapse of lumenal structures, accumulation of undegraded substrates and amassing of different types of lipids. Not all late endocytic compartments are affected, since exosome secretion is spared. These changes recall the Niemann-Pick type-C phenotype (NPC), but originate by a different mechanism, since, differently from NPC, they are not alleviated by cholesterol removal. Studies with analogues indicate that basic pKa and high water-solubility at acidic pH are crucial requirements for the interference with late endosomes/lysosomes and that, in this respect, dronedarone is at least as potent as amiodarone. These findings may have relevance in fields unrelated to rhythm control.


Assuntos
Amiodarona/farmacologia , Antiarrítmicos/farmacologia , Endossomos/efeitos dos fármacos , Endossomos/metabolismo , Doenças de Niemann-Pick/induzido quimicamente , Amiodarona/administração & dosagem , Amiodarona/análogos & derivados , Amiodarona/metabolismo , Androstenos/farmacologia , Animais , Antiarrítmicos/administração & dosagem , Antiarrítmicos/metabolismo , Células Cultivadas , Colesterol/metabolismo , Relação Dose-Resposta a Droga , Dronedarona , Humanos , Lisofosfolipídeos/metabolismo , Estrutura Molecular , Monoglicerídeos/metabolismo , Doenças de Niemann-Pick/metabolismo , Nocodazol/farmacologia
12.
Asia Pac J Clin Nutr ; 19(3): 412-6, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20805086

RESUMO

In order to assess secular trends in growth of the Vietnamese population following a period of rapid economic growth, a follow-up study on physical growth and nutritional status of adults was carried out in a rural section of the Red River delta, Vietnam 30 years after the original study. The initial study in 1976 found that average height and weight of Vietnamese adults was similar to data collected by French experts Huard and Bigot in 1938. Hence, no noticeable secular trends were observed in almost 40 years. However, the 2006 follow-up study revealed a positive secular trend in growth of adults, aged 16-60 years. The average increased rate in height of males was up to 1.1 cm/decade in the age group 26-40 years and up to 2.7 cm/decade in the age group 16-25 years. Nutritional status, as indicated by body mass index, increased in both sexes and in all age groups between 1976 and 2006.were observed. In 2006, average dietary intake of fat and animal protein was higher than that found in 1976. The percentage of energy from fat in the diet increased from 6% in 1976 to 16% in 2006. This study shows that Vietnam is entering the nutrition transition period.


Assuntos
Estatura , Peso Corporal , Estado Nutricional , População Rural/estatística & dados numéricos , Adolescente , Adulto , Índice de Massa Corporal , Gorduras na Dieta/administração & dosagem , Proteínas Alimentares/administração & dosagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores Sexuais , Vietnã
13.
Chem Commun (Camb) ; 46(41): 7703-5, 2010 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-20871918

RESUMO

We describe hydrated ionic liquids which have an intrinsic proton buffering action and hence an ability to control proton activity in an ionic medium.


Assuntos
Líquidos Iônicos/química , Soluções Tampão , Corantes/química , Concentração de Íons de Hidrogênio , Fenolsulfonaftaleína/química , Timolftaleína/análogos & derivados , Timolftaleína/química
14.
J Neurosci ; 30(26): 8974-83, 2010 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-20592218

RESUMO

The two proteases beta-secretase and gamma-secretase generate the amyloid beta peptide and are drug targets for Alzheimer's disease. Here we tested the possibility of targeting the cellular environment of beta-secretase cleavage instead of the beta-secretase enzyme itself. beta-Secretase has an acidic pH optimum and cleaves the amyloid precursor protein in the acidic endosomes. We identified two drugs, bepridil and amiodarone, that are weak bases and are in clinical use as calcium antagonists. Independently of their calcium-blocking activity, both compounds mildly raised the membrane-proximal, endosomal pH and inhibited beta-secretase cleavage at therapeutically achievable concentrations in cultured cells, in primary neurons, and in vivo in guinea pigs. This shows that an alkalinization of the cellular environment could be a novel therapeutic strategy to inhibit beta-secretase. Surprisingly, bepridil and amiodarone also modulated gamma-secretase cleavage independently of endosomal alkalinization. Thus, both compounds act as dual modulators that simultaneously target beta- and gamma-secretase through distinct molecular mechanisms. In addition to Alzheimer's disease, compounds with dual properties may also be useful for drug development targeting other membrane proteins.


Assuntos
Amiodarona/farmacologia , Secretases da Proteína Precursora do Amiloide/antagonistas & inibidores , Bepridil/farmacologia , Inibidores Enzimáticos/farmacologia , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/enzimologia , Amiodarona/química , Secretases da Proteína Precursora do Amiloide/metabolismo , Peptídeos beta-Amiloides/sangue , Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Animais , Bepridil/química , Encéfalo/efeitos dos fármacos , Encéfalo/enzimologia , Encéfalo/metabolismo , Linhagem Celular , Células Cultivadas , Inibidores Enzimáticos/química , Feminino , Cobaias , Humanos , Concentração de Íons de Hidrogênio , Técnicas In Vitro , Camundongos , Camundongos Transgênicos , Neurônios/efeitos dos fármacos , Neurônios/enzimologia , Neurônios/metabolismo , Nexinas de Proteases , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/metabolismo
15.
Asia Pac J Clin Nutr ; 17 Suppl 1: 116-8, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18296316

RESUMO

In addition to the burden of undernutrition, many recent studies in Vietnam demonstrate that overweight/obesity and a number of nutritionally- related chronic diseases (NRCD) (hypertension, diabetes, cardio-vascular diseases) are on the rise at an alarming rate. This could be the result of dietary and life style changes. The double burden of malnutrition (DBM) - a typical phenomenon during nutrition transition in developing countries, has been clearly reported in our country. Controlling nutritional deficiencies and newly emerging nutrition problems to reduce the double burden of malnutrition in Vietnam requires comprehensive and appropriate measures as set out in the National Nutrition Strategy 2001 - 2010, as well as a greater research effort on transitional nutrition.


Assuntos
Desnutrição/epidemiologia , Obesidade/epidemiologia , Pobreza , Adulto , Doença Crônica/epidemiologia , Doença Crônica/prevenção & controle , Países em Desenvolvimento , Feminino , Humanos , Masculino , Desnutrição/prevenção & controle , Pessoa de Meia-Idade , Obesidade/prevenção & controle , Prevalência , Vietnã/epidemiologia
16.
Am J Respir Cell Mol Biol ; 39(2): 142-9, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18314540

RESUMO

Amiodarone interferes with the endocytic pathway, inhibits proteolysis, and causes the formation of vacuoles, but uptake and intracellular distribution of the drug, origin of vacuoles, and functional consequences of amiodarone accumulation remain unclear. Our objective was to study amiodarone uptake, clarify the origin of vacuoles, and investigate the effect of amiodarone on the life cycle of the coronavirus responsible for the Severe Acute Respiratory Syndrome (SARS), which, to enter cells, relies on the proteolytic cleavage of a viral spike protein by the endosomal proteinase cathepsin L. Using alveolar macrophages, we studied uptake of (125)I-amiodarone and (125)I-B2, an analog lacking the lateral group diethylamino-beta-ethoxy, and analyzed the effects of amiodarone on the distribution of endosomal markers and on the uptake of an acidotropic dye. Furthermore, using Vero cells, we tested the impact of amiodarone on the in vitro spreading of the SARS coronavirus. We found that (1) amiodarone associates with different cell membranes and accumulates in acidic organelles; (2) the diethylamino-beta-ethoxy group is an important determinant of uptake; (3) vacuoles forming upon exposure to amiodarone are enlarged late endosomes; (4) amiodarone inhibits the spreading in vitro of SARS coronavirus; and (5) trypsin cleavage of the viral spike protein before infection, which permits virus entry through the plasma membrane, does not impair amiodarone antiviral activity. We conclude that amiodarone alters late compartments of the endocytic pathway and inhibits SARS coronavirus infection by acting after the transit of the virus through endosomes.


Assuntos
Amiodarona/farmacologia , Antivirais/farmacologia , Endossomos/metabolismo , Macrófagos Alveolares/metabolismo , Síndrome Respiratória Aguda Grave/metabolismo , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/efeitos dos fármacos , Amiodarona/farmacocinética , Animais , Antivirais/farmacocinética , Catepsina L , Catepsinas/metabolismo , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Chlorocebus aethiops , Cisteína Endopeptidases/metabolismo , Citoplasma/efeitos dos fármacos , Citoplasma/metabolismo , Endossomos/efeitos dos fármacos , Humanos , Isótopos de Iodo/química , Macrófagos Alveolares/efeitos dos fármacos , Macrófagos Alveolares/virologia , Glicoproteínas de Membrana/metabolismo , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/fisiologia , Síndrome Respiratória Aguda Grave/tratamento farmacológico , Síndrome Respiratória Aguda Grave/virologia , Glicoproteína da Espícula de Coronavírus , Vacúolos/efeitos dos fármacos , Vacúolos/metabolismo , Células Vero , Proteínas do Envelope Viral/metabolismo
17.
J Cardiovasc Pharmacol ; 50(5): 578-84, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18030069

RESUMO

Sexual dimorphisms of atherosclerosis and the susceptibility to arrhythmias and antiarrhythmic treatment have been reported. This study investigated acute effects of amiodarone on endothelium-dependent relaxation in the aorta of male and female apoE0 mice with advanced atherosclerosis. Amiodarone tissue uptake was quantified by high-performance liquid chromatography, and xanthine oxidase-dependent superoxide anion formation was investigated in vitro in presence or absence of amiodarone. Incubation with amiodarone for 30 min improved endothelium-dependent relaxation, which was associated with rapid vascular accumulation of amiodarone (P < 0.001) that was sex-dependent. In males, reduced endothelium-dependent relaxation was improved by amiodarone (from 88 +/- 3% to 100 +/- 2%, P < 0.01). Spontaneous phasic contractions, which were greater in females than in males (P < 0.001), were completely abolished by amiodarone (P < 0.0001). Amiodarone also inhibited generation of superoxide anion (P < 0.0001). These data show that amiodarone rapidly accumulates in atherosclerotic vascular tissue, abolishes vascular autorhythmicity, and improves endothelium-dependent function in atherosclerotic arteries. Antioxidant and vasodilator effects following amiodarone administration may contribute to its antiarrhythmic effects.


Assuntos
Amiodarona/farmacologia , Antioxidantes/farmacologia , Doença da Artéria Coronariana/fisiopatologia , Vasoconstrição/efeitos dos fármacos , Vasodilatação/efeitos dos fármacos , Acetilcolina/farmacologia , Amiodarona/farmacocinética , Animais , Antioxidantes/farmacocinética , Aorta/metabolismo , Aorta/patologia , Aorta/fisiopatologia , Apolipoproteínas E/genética , Doença da Artéria Coronariana/metabolismo , Doença da Artéria Coronariana/patologia , Feminino , Masculino , Camundongos , Camundongos Endogâmicos , Camundongos Knockout , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/fisiopatologia , Nitroprussiato/farmacologia , Fenilefrina/farmacologia , Fatores Sexuais , Superóxidos/metabolismo , Vasodilatadores/farmacologia , Xantina/metabolismo , Xantina Oxidase/metabolismo
18.
Arthritis Rheum ; 56(11): 3564-74, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17968936

RESUMO

OBJECTIVE: Microparticles are small vesicles that are released from activated or dying cells and that occur abundantly in the synovial fluid of patients with rheumatoid arthritis (RA). The goal of these studies was to elucidate the mechanisms by which microparticles activate synovial fibroblasts to express a proinflammatory phenotype. METHODS: Microparticles from monocytes and T cells were isolated by differential centrifugation. Synovial fibroblasts were cocultured with increasing numbers of microparticles. Gene expression was analyzed by real-time polymerase chain reaction and confirmed by Western blotting and enzyme immunoassay. Arachidonic acid labeled with tritium was used to study the transport of biologically active lipids by microparticles. The roles of NF-kappaB and activator protein 1 (AP-1) signaling were analyzed with electrophoretic mobility shift assay and transfection with small interfering RNA and IkappaB expression vectors. RESULTS: Microparticles strongly induced the synthesis of cyclooxygenase 2 (COX-2), microsomal prostaglandin E synthase 1 (mPGES-1), and prostaglandin E(2) (PGE(2)). In contrast, no up-regulation of COX-1, mPGES-2, cytosolic PGES, or phospholipase A(2) was observed. The induction of PGE(2) was blocked by selective inhibition of COX-2. Microparticles activated NF-kappaB, AP-1, p38, and JNK signaling in synovial fibroblasts. Inhibition of NF-kappaB, AP-1, and JNK signaling reduced the stimulatory effects. Arachidonic acid was transported from leukocytes to fibroblasts by microparticles. Arachidonic acid derived from microparticles was converted to PGE(2) by synovial fibroblasts. CONCLUSION: These results demonstrate that microparticles up-regulate the production of PGE(2) in synovial fibroblasts by inducing COX-2 and mPGES-1. These data provide evidence for a novel mechanism by which microparticles may contribute to inflammation and pain in RA.


Assuntos
Artrite Reumatoide/metabolismo , Ciclo-Oxigenase 2/genética , Dinoprostona/metabolismo , Fibroblastos/enzimologia , Oxirredutases Intramoleculares/genética , Ácidos Araquidônicos/metabolismo , Artrite Reumatoide/imunologia , Artrite Reumatoide/patologia , Células Cultivadas , Ciclo-Oxigenase 2/metabolismo , Inibidores de Ciclo-Oxigenase/farmacologia , Fibroblastos/imunologia , Fibroblastos/patologia , Humanos , Oxirredutases Intramoleculares/metabolismo , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Microssomos/enzimologia , Monócitos/metabolismo , Monócitos/ultraestrutura , NF-kappa B/metabolismo , Nitrobenzenos/farmacologia , Osteoartrite/imunologia , Osteoartrite/metabolismo , Osteoartrite/patologia , Tamanho da Partícula , Prostaglandina-E Sintases , Transdução de Sinais/imunologia , Sulfonamidas/farmacologia , Líquido Sinovial/metabolismo , Linfócitos T/metabolismo , Linfócitos T/ultraestrutura , Fator de Transcrição AP-1/metabolismo , Regulação para Cima/imunologia
19.
Asia Pac J Clin Nutr ; 16(2): 274-8, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17468083

RESUMO

Reduction in childhood malnutrition in Vietnam between 1990 and 2004 was assessed using data from 5 national surveys. The prevalence of malnutrition, including stunting, declined significantly for underweight from 45% in 1990 to 26.6% in 2004. While the average reduction was 1.3% per year in the period from 1990 to 2000, it was 1.8% per year in the period from 2000 to 2004. The prevalence of stunting declined from 56.5% in 1990 to 30.7% in 2004, with an average reduction of 2% per year in the period from 1990 to 2000 and 1.5% per year in the period from 2000 to 2004. There were clear differences in the decrease in malnutrition prevalence between urban, rural and mountainous areas, the reduction being highest in the urban regions and lowest in the mountainous areas. Regression analysis showed that the nutrition status of the child is positively related to better household living conditions and to the educational level of the father, but not the mother. Stunting is higher in children whose parents are farmers and higher in households with more children. Stunting prevalence is lower in households with safe water access and hygienic toilets. In future , the dramatic reduction is childhood malnutrition as seen in the period 1990 to 2004 might not continue. More comprehensive apptoaches will be needed to lower childhood malnutrition in Vietnam further.


Assuntos
Transtornos da Nutrição Infantil/epidemiologia , Kwashiorkor/epidemiologia , Estado Nutricional , Pobreza , Desnutrição Proteico-Calórica/epidemiologia , Estatura/fisiologia , Peso Corporal/fisiologia , Transtornos da Nutrição Infantil/etiologia , Transtornos da Nutrição Infantil/prevenção & controle , Pré-Escolar , Escolaridade , Feminino , Humanos , Lactente , Kwashiorkor/etiologia , Kwashiorkor/prevenção & controle , Masculino , Prevalência , Desnutrição Proteico-Calórica/etiologia , Desnutrição Proteico-Calórica/prevenção & controle , Saúde da População Rural , Saúde da População Urbana , Vietnã/epidemiologia
20.
Am J Clin Nutr ; 85(4): 1112-20, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17413113

RESUMO

BACKGROUND: More information is needed on the efficacy of carotenoids from plant foods in improving vitamin A status. OBJECTIVE: We aimed to quantify the efficacy of provitamin A-rich vegetables and fruit in improving vitamin A status. DESIGN: Breastfeeding women in 9 rural communes in Vietnam were randomly allocated to 1 of 4 groups: the vegetable group (n = 73), which ingested 5.6 mg beta-carotene/d from green leafy vegetables; the fruit group (n = 69), which ingested 4.8 mg beta-carotene/d from orange or yellow fruit; the retinol-rich group (n = 70), which ingested 610 microg retinol/d from animal foods and 0.6 mg beta-carotene/d; and the control group (n = 68), which ingested 0.4 mg beta-carotene/d. Meals of groups 1, 2, and 4 contained <30 microg retinol/d. Lunch and dinner were provided 6 d/wk for 10 wk. RESULTS: Mean (95% CI) changes in serum retinol concentrations of the vegetable, fruit, retinol-rich, and control groups were 0.09 (0.03, 0.16), 0.13 (0.07, 0.19), 0.25 (0.17, 0.33), and 0.00 (-0.06, 0.06) micromol/L, respectively. Mean (95% CI) changes in breast-milk retinol concentrations were 0.15 (0.04, 0.27), 0.15 (0.02, 0.28), 0.48 (0.32, 0.64), and -0.06 (-0.21, 0.09) micromol/L, respectively. According to these findings, the equivalent of 1 microg retinol would be 12 microg beta-carotene (95% CI: 8, 22 microg) for fruit and 28 microg beta-carotene (17, 84 microg) for green leafy vegetables. Thus, apparent mean vitamin A activity of carotenoids in fruit and in leafy vegetables was 50% (95% CI: 27%, 75%) and 21% (7%, 35%), respectively, of that assumed. CONCLUSION: The bioavailability of carotenoids from vegetables and fruit is less than previously assumed.


Assuntos
Frutas , Lactação/metabolismo , Leite Humano/química , Verduras , Vitamina A/administração & dosagem , Vitamina A/farmacocinética , Adulto , Disponibilidade Biológica , Carotenoides/administração & dosagem , Carotenoides/farmacocinética , Feminino , Frutas/química , Humanos , Lactente , Absorção Intestinal , Leite Humano/efeitos dos fármacos , Necessidades Nutricionais , Estado Nutricional , População Rural , Verduras/química , Vietnã , Vitaminas/administração & dosagem , Vitaminas/farmacocinética
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