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1.
Molecules ; 26(15)2021 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-34361827

RESUMO

Grammicin, a polyketide metabolite produced by the endolichenic fungus Xylaria grammica KCTC 13121BP, shows strong nematicidal activity against Meloidogyne incognita. This study was performed to elucidate the grammicin biosynthesis pathway of X. grammica KCTC 13121BP and to examine the nematicidal activity of the biosynthesis intermediates and derivatives against M. incognita. Two grammicin biosynthesis intermediates were isolated from a T-DNA insertion transformant (strain TR-74) of X. grammica KCTC 13121BP and identified as 2-(hydroxymethyl)cyclohexa-2,5-diene-1,4-dione (compound 1) and 2,5-dihydroxybenzaldehyde (compound 2), which were also reported to be intermediates in the biosynthesis pathway of patulin, an isomer of grammicin. This indicates that the grammicin biosynthesis pathway overlaps almost with that of patulin, except for the last few steps. Among 13 grammicin biosynthesis intermediates and their derivatives (except grammicin), toluquinol caused the highest M. incognita J2 mortality, with an LC50/72 h value of 11.13 µg/mL, which is similar to grammicin with an LC50/72 h value of 15.95 µg/mL. In tomato pot experiments, the wettable powder type formulations (WP) of toluquinol (17.78 µg/mL) and grammicin (17.78 µg/mL) also effectively reduced gall formation on the roots of tomato plants with control values of 72.22% and 77.76%, respectively, which are much higher than abamectin (16.67%), but lower than fosthiazate (100%). The results suggest that toluquinol can be used directly as a biochemical nematicide or as a lead molecule for the development of new synthetic nematicides for the control of root-knot nematode diseases.


Assuntos
Antinematódeos/farmacologia , Ascomicetos/fisiologia , Lycopersicon esculentum/efeitos dos fármacos , Doenças das Plantas/prevenção & controle , Policetídeos/farmacologia , Tylenchoidea/efeitos dos fármacos , Animais , Lycopersicon esculentum/microbiologia , Doenças das Plantas/parasitologia
2.
Nanotechnology ; 2021 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-34359057

RESUMO

In this study, we report a facile and effective approach for large-scale production of nitrogen-doped TiO2 nanocrystals (UNTs) by a combination of ultrasonic irradiation and electrochemistry at room temperature using NH4NO3 electrolyte as the nitrogen source. The as-prepared UNTs were then characterized by X-ray diffraction, Raman spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy, transmission electron microscopy, and UV-Visible diffuse reflectance spectroscopy. The results indicated that the nitrogen content of UNTs reached 9.3% and bandgap energy of 2.62 eV, thus gave the high photocatalytic degradation of methylene blue under visible light irradiation. The mechanism for the formation of UNTs by ultrasonic-assisted electrochemical approach was also proposed.

3.
Artigo em Inglês | MEDLINE | ID: mdl-34208212

RESUMO

As a response to the coronavirus disease 2019 (COVID-19) pandemic, Vietnam enforced strict quarantine, contact tracing and physical distancing policies resulting in one of the lowest numbers of individuals infected with severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) globally. This study aimed to determine the prevalence of SARS-CoV-2 antibody positivity among high-risk populations in Vietnam. A prevalence survey was undertaken within four communities in Vietnam, where at least two COVID-19 cases had been confirmed. Participants were classified according to the location of exposure: household contacts, close contacts, community members, and healthcare workers (HCWs) responsible for treating COVID-19 cases. Participants completed a baseline questionnaire and SARS-CoV-2 IgG antibodies were quantified using a commercial assay. A total of 3049 community members and 149 health care workers consented to the study. Among 13 individuals who were seropositive (0.4%), five household contacts (5/27, 18.5%), one close contact (1/53, 1.9%), and seven community members (7/2954, 0.2%) had detectable SARS-CoV-2 antibodies. All HCWs were negative for SARS-CoV-2 antibodies. Participants were tested a median of 15.1 (interquartile range from 14.9 to 15.2) weeks after exposure. Our study found a low prevalence of SARS-CoV-2 antibodies in high-risk communities and healthcare workers in communities in Vietnam with known COVID-19 cases.


Assuntos
COVID-19 , SARS-CoV-2 , Anticorpos Antivirais , Pessoal de Saúde , Humanos , Pandemias , Prevalência , Estudos Soroepidemiológicos , Vietnã/epidemiologia
4.
Int J Mol Sci ; 22(13)2021 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-34199089

RESUMO

The meniscus possesses low self-healing properties. A perfect regenerative technique for this tissue has not yet been developed. This work aims to evaluate the role of hypoxia in meniscal development in vitro. Menisci from neonatal pigs (day 0) were harvested and cultured under two different atmospheric conditions: hypoxia (1% O2) and normoxia (21% O2) for up to 14 days. Samples were analysed at 0, 7 and 14 days by histochemical (Safranin-O staining), immunofluorescence and RT-PCR (in both methods for SOX-9, HIF-1α, collagen I and II), and biochemical (DNA, GAGs, DNA/GAGs ratio) techniques to record any possible differences in the maturation of meniscal cells. Safranin-O staining showed increments in matrix deposition and round-shape "fibro-chondrocytic" cells in hypoxia-cultured menisci compared with controls under normal atmospheric conditions. The same maturation shifting was observed by immunofluorescence and RT-PCR analysis: SOX-9 and collagen II increased from day zero up to 14 days under a hypoxic environment. An increment of DNA/GAGs ratio typical of mature meniscal tissue (characterized by fewer cells and more GAGs) was observed by biochemical analysis. This study shows that hypoxia can be considered as a booster to achieve meniscal cell maturation, and opens new opportunities in the field of meniscus tissue engineering.


Assuntos
Diferenciação Celular , Hipóxia/metabolismo , Menisco/citologia , Menisco/metabolismo , Animais , Biomarcadores , Células Cultivadas , Condrócitos/metabolismo , Expressão Gênica , Glicosaminoglicanos/metabolismo , Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Imuno-Histoquímica , Suínos , Engenharia Tecidual/métodos
5.
Diagnostics (Basel) ; 11(2)2021 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-33672241

RESUMO

HIV self-testing has emerged as a safe and effective approach to increase the access to and uptake of HIV testing and treatment, especially for key populations. Applying self-testing to hepatitis C virus (HCV) may also offer an additional way to address low coverage of HCV testing and to accelerate elimination efforts. To understand the potential for HCV self-testing (HCVST), an observational study was conducted to assess the acceptability and usability of the OraQuick® HCV Self-Test (prototype) among people who inject drugs (PWID) and men who have sex with men (MSM) in Thai Nguyen, a province in northern Vietnam. A total of 105 PWID and 104 MSM were eligible and agreed to participate in the study. Acceptability, defined as the proportion of participants among eligible subjects who agreed to participate in the study, was 92.9% in PWID and 98.6% in MSM. Compared to MSM, PWID were older (median age: 45 vs. 22 years; p < 0.0001) and had a lower education level (high school and college: 38.1% vs. 100%; p < 0.0001). HCVST usability was high among MSM with fewer observed mistakes, difficulties, or participants requiring assistance (33.7%, 28.8%, and 17.3%, respectively) compared to PWID (62.9%, 53.3%, and 66.7%, respectively; all p < 0.0001)). Inter-reader and inter-operator agreement were good in both groups (Kappa coefficient range: 0.61-0.99). However, the concordance between HCVST and study staff -read or performed HCV testing was lower among PWID than MSM (inter-reader concordance 88.6% vs. 99.0% and inter-operator concordance 81.9% vs. 99%). Overall, HCVST was highly acceptable with moderate to high usability among PWID and MSM in Thai Nguyen. Efforts to provide support and assistance may be needed to optimize performance, particularly for PWID populations and for those who are older and with lower literacy or education levels.

6.
Nanotechnology ; 2021 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-33455951

RESUMO

In this study, oxygenated graphene nanosheets (OGNs) was successfully synthesized by a simple electrochemical exfoliation approach and applied for removing methylene blue (MB) in aqueous solution. The surface morphology and structure of the OGNs were characterized by scanning electron microscopy, transmission electron microscopy, Raman, and X-ray photoelectron spectroscopy. The adsorption performance of OGNs towards aqueous MB was tested by batch experiments. Results showed that a large number of functional groups in OGNs enhanced the removal of methylene blue from the aqueous solution due to the electrostatic interactions between the electrochemically oxygenated groups (e.g., C-OH, C-O, and C=O) and dye molecules. By using Langmuir adsorption isotherm, the maximum MB adsorption capacity (qmax) was determined as high as 476.19 mg/g. These results suggested that the as-prepared OGNs is an effective and promising adsorbent for removing MB, which could be studied extensively for color removal in wastewater treatment.

7.
Int J STD AIDS ; 32(2): 135-143, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33349143

RESUMO

Pregnant women in Vietnam have a high prevalence of hepatitis B virus (HBV) and low prevalence of human immunodeficiency virus (HIV) and syphilis. This study aims to assess the feasibility and benefit of universal testing for HIV, HBV and syphilis in antenatal care (ANC) services. A pilot project was conducted in the Thai Nguyen province of Vietnam between 2012 and 2014. HIV, HBV and syphilis testing were offered to pregnant women. Interventions to eliminate mother-to child-transmission (MTCT) of the three pathogens were provided to infected mothers and their infants. Descriptive analysis was conducted, and the number of infections averted from integrating hepatitis B tests into ANC was estimated. Testing coverage for HIV, HBV and syphilis for the cohort of pregnant women during the pilot project was 98%. Prevalence of HIV, HBV and syphilis infections in this cohort was 0.14%, 7.8%, and 0.03%, respectively. No infant was infected with HIV or syphilis, while HBV infection was diagnosed in 27 infants (13.9%). An estimated 23 mother to child HBV infections were prevented by integrated interventions. The triple prevention of mother-to-child transmission of HIV, HBV and syphilis is feasible. Investment in the expansion of the integrated approach is required to achieve the goal of eliminating MTCT.


Assuntos
Prestação Integrada de Cuidados de Saúde/economia , Infecções por HIV/diagnóstico , Hepatite B/diagnóstico , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Complicações Infecciosas na Gravidez/prevenção & controle , Sífilis/diagnóstico , Adulto , Análise Custo-Benefício , Estudos de Viabilidade , Feminino , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Hepatite B/epidemiologia , Hepatite B/prevenção & controle , Humanos , Lactente , Projetos Piloto , Gravidez , Complicações Infecciosas na Gravidez/epidemiologia , Gestantes , Cuidado Pré-Natal/organização & administração , Diagnóstico Pré-Natal , Prevalência , Sífilis/epidemiologia , Sífilis/prevenção & controle , Tailândia/epidemiologia , Vietnã/epidemiologia , Adulto Jovem
8.
Zootaxa ; 4789(1): zootaxa.4789.1.5, 2020 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-33056447

RESUMO

We describe a new species of Cyrtodactylus on the basis of four specimens collected from Phu My, Binh Dinh Province, southern Vietnam. Cyrtodactylus phumyensis sp. nov. is distinguished from the remaining Indochinese bent-toed geckos by a combination of the following characters: size small (SVL up to 66.8 mm); two internasals; dorsal tubercle rows 18 or 19 at midbody; ventral scale rows 33-41; ventrolateral folds slightly developed; each thigh with 5-7 enlarged femoral scales; femoral pores absent in males and female; a series of 5-7 precloacal pores plus a pitted, enlarged precloacal scale in males; 6 pitted, enlarged precloacal scales in female; paravertebral tubercles 20-23; lamellae under toe IV 18-21; small subcaudal scales, not transversely enlarged; two irregular dark longitudinal stripes on shoulder. In phylogenetic analyses, the new species is recovered as a member of the Cyrtodactylus irregularis species group, and strongly supported as a sister taxon of C. cucdongensis from Khanh Hoa Province.


Assuntos
Lagartos , Estruturas Animais , Animais , Feminino , Masculino , Filogenia , Vietnã
9.
Int J Mol Sci ; 21(14)2020 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-32698534

RESUMO

To understand the regenerative effect of platelet-released molecules in bone repair one should investigate the cascade of events involving the resident osteoblast population during the reconstructive process. Here the in vitro response of human osteoblasts to a platelet lysate (PL) stimulus is reported. Quiescent or very slow dividing osteoblasts showed a burst of proliferation after PL stimulation and returned to a none or very slow dividing condition when the PL was removed. PL stimulated osteoblasts maintained a differentiation capability in vitro and in vivo when tested in absence of PL. Since angiogenesis plays a crucial role in the bone healing process, we investigated in PL stimulated osteoblasts the activation of hypoxia-inducible factor 1-alpha (HIF-1α) and signal transducer and activator of transcription 3 (STAT3) pathways, involved in both angiogenesis and bone regeneration. We observed phosphorylation of STAT3 and a strong induction, nuclear translocation and DNA binding of HIF-1α. In agreement with the induction of HIF-1α an enhanced secretion of vascular endothelial growth factor (VEGF) occurred. The double effect of the PL on quiescent osteoblasts, i.e., resumption of proliferation and activation of pathways promoting both angiogenesis and bone formation, provides a rationale to the application of PL as therapeutic agent in post-traumatic bone repair.


Assuntos
Plaquetas/metabolismo , Regeneração Óssea , Osso e Ossos/irrigação sanguínea , Osso e Ossos/lesões , Neovascularização Fisiológica , Osteoblastos/citologia , Adulto , Animais , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Camundongos , Osteoblastos/metabolismo , Osteogênese , Fator A de Crescimento do Endotélio Vascular/metabolismo
10.
Cells ; 9(3)2020 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-32204578

RESUMO

Bone is an active tissue where bone mineralization and resorption occur simultaneously. In the case of fracture, there are numerous factors required to facilitate bone healing including precursor cells and blood vessels. To evaluate the interaction between bone marrow-derived mesenchymal stem cells (BMSC)-the precursor cells able to differentiate into bone-forming cells and human umbilical vein endothelial cells (HUVEC)-a cell source widely used for the study of blood vessels. We performed direct coculture of BMSC and HUVEC in normoxia and chemically induced hypoxia using Cobalt(II) chloride and Dimethyloxaloylglycine and in the condition where oxygen level was maintained at 1% as well. Cell proliferation was analyzed by crystal violet staining. Osteogenesis was examined by Alizarin Red and Collagen type I staining. Expression of angiogenic factor-vascular endothelial growth factor (VEGF) and endothelial marker-von Willebrand factor (VWF) were demonstrated by immunohistochemistry and enzyme-linked immunosorbent assay. The quantitative polymerase chain reaction was also used to evaluate gene expression. The results showed that coculture in normoxia could retain both osteogenic differentiation and endothelial markers while hypoxic condition limits cell proliferation and osteogenesis but favors the angiogenic function even after 1 of day treatment.


Assuntos
Diferenciação Celular , Células Endoteliais da Veia Umbilical Humana/citologia , Células-Tronco Mesenquimais/citologia , Neovascularização Fisiológica , Osteogênese , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/metabolismo , Hipóxia Celular , Proliferação de Células , Técnicas de Cocultura , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Células-Tronco Mesenquimais/metabolismo , Pessoa de Meia-Idade , Fator de von Willebrand/metabolismo
11.
Biomed Res Int ; 2019: 8581379, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31467915

RESUMO

Background. Clonorchis sinensis/Opisthorchis viverrini and minute intestinal flukes (MIF) such as Haplorchis pumilio and H. taichui are fish-borne trematodes (FBT) that may coexist in regions where local people have a habit of eating raw fish like Vietnam. Responses to FBT should be verified according to the data on the distribution of these flukes. This study aims to explore the prevalence of different species of FBT and related factors among local people in a northern province of Vietnam. Methods. A cross-sectional study was conducted in Kim Son and Yen Khanh districts, Ninh Binh province, between March 2016 and March 2017. Four hundred people aged 15 years or older were interviewed and gave stool samples. The FBT eggs in faecal samples were enumerated by modified formalin-ether technique and identified by sequencing of the second internal transcribed spacer (ITS2) region. Result. Among the 400 persons, 19.5% were infected with FBT. On univariate analysis, eating raw fish was the main risk factor (odds ratios (OR)) of 6.769 (95% confidence interval (CI) of 2.655-17.259) followed by being of male gender (3.994 (CI95% 2.117-7.536)) and drinking alcohol (2.680 (CI95% 1.440-4.986)), respectively. There was no risk of increased infection among those living at home without hygienic latrines, those living close to rivers or having ponds, or those raising cats or dogs. By multivariate analysis, FBT infection was only related to the consumption of raw fish and gender. Seventy stool samples with a sufficient amount of faecal matter were subjected to DNA extraction, 42.85% of them yielded DNA production, and all were of Clonorchis sinensis. Conclusion. Results of the study showed the high prevalence of infection of fish-borne trematode, mostly C. sinensis among humans in Ninh Binh province. The prevention of FBT should be strengthened with programs detailed according to the distribution of FBT in different endemic areas.


Assuntos
Peixes/parasitologia , Alimentos Crus/parasitologia , Infecções por Trematódeos/epidemiologia , Infecções por Trematódeos/parasitologia , Adolescente , Adulto , Idoso , Animais , Fezes/parasitologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Especificidade da Espécie , Trematódeos/patogenicidade , Infecções por Trematódeos/transmissão , Vietnã/epidemiologia , Adulto Jovem
12.
J Int AIDS Soc ; 22 Suppl 3: e25301, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31321903

RESUMO

INTRODUCTION: The HIV epidemic in Vietnam is concentrated in key populations and their partners - people who inject drugs, men who have sex with men, sex workers and partners of people living with HIV. These groups have poor access to and uptake of conventional HIV testing services (HTS). To address this gap, lay provider- and self-testing and assisted partner notification (aPN) were introduced and delivered by the community. We explored the feasibility and effectiveness of implementing aPN as part of community testing services for key populations. METHODS: Lay provider testing and self-testing was started in January 2017, and targeted key populations and their partners. Since July 2017, aPN was introduced. HTS was offered at drop-in houses or coffee shops in Thai Nguyen and Can Tho provinces. All self-testing was assisted and observed by peer educators. Both in-person and social network methods were used to mobilize key populations to test for HIV and offer HTS to partners of people living with HIV. Client-level data, including demographic information and self-reported risk behaviour, were collected on site by peer educators. RESULTS: Between January 2017 and May 2018, 3978 persons from key populations were tested through community-led HTS; 66.7% were first-time testers. Of the 3978 clients, 3086 received HTS from a lay provider and 892 self-tested in the presence of a lay provider. Overall, 245 (6.2% of tested clients) had reactive results, 231 (94.3%) were confirmed to be HIV positive; 215/231 (93.1%) initiated antiretroviral therapy (ART). Of 231 adult HIV-positive clients, 186 (80.5%) were provided voluntary aPN, and 105 of their partners were contacted and received HTS. The ratio of partners who tested for HIV per index client was 0.56. Forty-four (41.9%) partners of index clients receiving HTS were diagnosed with HIV, 97.7% initiated ART during the study period. No social harm was identified or reported. CONCLUSIONS: Including aPN as part of community-led HTS for key populations and their partners is feasible and effective, particularly for reaching first-time testers and undiagnosed HIV clients. Scale-up of aPN within community-led HTS for key populations is essential for achieving the United Nations 90-90-90 targets in Vietnam.


Assuntos
Busca de Comunicante , Infecções por HIV/diagnóstico , Parceiros Sexuais , Adulto , Serviços de Saúde Comunitária , Busca de Comunicante/métodos , Epidemias , Estudos de Viabilidade , Feminino , Infecções por HIV/epidemiologia , Homossexualidade Masculina , Humanos , Masculino , Programas de Rastreamento , Projetos Piloto , Autocuidado , Profissionais do Sexo , Minorias Sexuais e de Gênero , Vietnã/epidemiologia , Adulto Jovem
13.
Stem Cells Int ; 2019: 9178436, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31191688

RESUMO

Total hip arthroplasty (THA) represents one of the commonest surgical procedures in the orthopedic field. Osteointegration of the implant with native bone is essential for an optimal result; thus, the quality of the patient's bone surrounding the implant (i.e., the bone stock) is crucial. However, in some cases, the bone stock is insufficient and needs to be improved with autologous grafts rich in multipotent cells (i.e., from the iliac crest, from the head of the femur, or from the subchondral bone harvested from the acetabulum) or allogenic frozen bone. It is not known if the harvesting site may influence the osteogenic potential of these cells. Thus, our aim was to characterize and compare multipotent cells collected from the bone marrow, acetabular subchondral bone, and trabecular bone on the femoral head with a focus on osteogenic differentiation. The cells from three sources had a fibroblast-like phenotype and expressed surface antigens CD73, CD90, and CD105 and are negative to CD11b, CD34, and CD45. Although all these cells could be induced to differentiate into osteoblasts, chondrocytes, and adipocytes, they displayed different differentiation potentials. In osteogenic differentiation condition, the cells from the acetabulum had the lowest accumulation of calcium deposit while the cells originated from the bone marrow and femur created a considerably increased amount of the deposit. These findings were confirmed by quantitative polymerase chain reaction (qPCR). In chondrogenic and adipogenic conditions, bone marrow cells possessed a predominant differential capacity compared with the others, illustrated by high collagen type II expression together with a cartilage-like lacuna structure and the presence of fat-specific markers, respectively. To our knowledge, this is the first study comparing and demonstrating that the progenitor cells obtained from diverse surgical sites in hip replacement procedure share common characteristics of MSC but differ about plasticity and may provide rational for clinical application in cell therapy and bone grafting. The project number L1033 is registered with ClinicalTrials.gov NCT03369457.

14.
Glob Pediatr Health ; 6: 2333794X19843917, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31106242

RESUMO

Health insurance reform for children younger than 6 years of age was implemented in 2005. The study aimed to describe the health insurance card status, health care services use, and associated factors. The cross-sectional study was conducted with 210 Hmong mothers of children younger than 6 years of age, and of those, 118 mothers having an ill child in the previous 4 weeks were selected in this study. Descriptive statistics and multiple logistic regression were applied to predict the associated factors. In all, 42.9% of children had health insurance cards and 45.8% ill children accessed public health facilities. The factors included children's age, mothers' knowledge of the free health care policy, mothers' knowledge about one sign of lung infection of their children associated with health insurance status, and health care services use. In conclusion, the 2005 reform of child health insurance policy has brought a modest impact on insurance coverage of children younger than 6 years of age and health care services use. Mothers' knowledge of free health care policy should be improved.

15.
J Healthc Eng ; 2019: 5156416, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30863524

RESUMO

Early detection and classification of pulmonary nodules using computer-aided diagnosis (CAD) systems is useful in reducing mortality rates of lung cancer. In this paper, we propose a new deep learning method to improve classification accuracy of pulmonary nodules in computed tomography (CT) scans. Our method uses a novel 15-layer 2D deep convolutional neural network architecture for automatic feature extraction and classification of pulmonary candidates as nodule or nonnodule. Focal loss function is then applied to the training process to boost classification accuracy of the model. We evaluated our method on the LIDC/IDRI dataset extracted by the LUNA16 challenge. The experiments showed that our deep learning method with focal loss is a high-quality classifier with an accuracy of 97.2%, sensitivity of 96.0%, and specificity of 97.3%.


Assuntos
Aprendizado Profundo , Neoplasias Pulmonares/classificação , Neoplasias Pulmonares/diagnóstico por imagem , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Nódulo Pulmonar Solitário/classificação , Nódulo Pulmonar Solitário/diagnóstico por imagem , Bases de Dados Factuais , Aprendizado Profundo/estatística & dados numéricos , Detecção Precoce de Câncer/métodos , Detecção Precoce de Câncer/estatística & dados numéricos , Humanos , Redes Neurais de Computação , Interpretação de Imagem Radiográfica Assistida por Computador/estatística & dados numéricos , Tomografia Computadorizada por Raios X/estatística & dados numéricos
16.
J Med Virol ; 91(1): 56-64, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30132913

RESUMO

Human enterovirus 71 (EV71) is the major etiologic agent of hand, foot, and mouth disease (HFMD). EV71 outbreaks have been reported in Dak Lak in recent years, however, the genotypes/subgenotypes information and phylogeny of circulating EV71 strains are limited. The objectives of this study were to determine the genotypes/subgenotypes and investigate the phylogeny of EV71 isolates in Dak Lak over a 6-year period. Viruses were isolated from clinical samples from patients with HFMD. In total, 43 EV71 isolates circulated in Dak Lak during 2011-2016 were used for the phylogenetic analysis using complete VP1 gene. The phylogenetic analysis of the VP1 gene revealed that two major genotypes, B and C, were found. Among the 43 EV71 strains, 29 belonged to subgenotype C4, 2 belonged to subgenotype C5, and 12 belonged to subgenotype B5. Of these, the subgenotype C4 was predominant in 2011-2013 and this was later replaced by the subgenotype B5 in 2014. The subgenotype B5 was dominant between 2014 and 2015, and then C4 recirculated in 2016. Our study also indicated that the subgenotypes C4 and B5 emerged into Dak Lak were closely related to variants causing epidemics of HFMD in the southern and central region of Vietnam and Thailand. Sequence analysis showed that nine amino acid mutations were detected in the VP1 region. Our results identified two significant amino acid substitutions (D31N and E145G/Q) associated with enhancing EV71 virulence.


Assuntos
Enterovirus Humano A/classificação , Enterovirus Humano A/genética , Genótipo , Doença de Mão, Pé e Boca/epidemiologia , Doença de Mão, Pé e Boca/virologia , Epidemiologia Molecular , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Enterovirus Humano A/isolamento & purificação , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Filogenia , Vietnã/epidemiologia , Adulto Jovem
17.
Influenza Other Respir Viruses ; 12(5): 632-642, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29754431

RESUMO

BACKGROUND: In 2016, as a component of the Global Health Security Agenda, the Vietnam Ministry of Health expanded its existing influenza sentinel surveillance for severe acute respiratory infections (SARI) to include testing for 7 additional viral respiratory pathogens. This article describes the steps taken to implement expanded SARI surveillance in Vietnam and reports data from 1 year of expanded surveillance. METHODS: The process of expanding the suite of pathogens for routine testing by real-time reverse transcriptase-polymerase chain reaction (rRT-PCR) included laboratory trainings, procurement/distribution of reagents, and strengthening and aligning SARI surveillance epidemiology practices at sentinel sites and regional institutes (RI). RESULTS: Surveillance data showed that of 4003 specimens tested by the RI laboratories, 20.2% (n = 810) were positive for influenza virus. Of the 3193 influenza-negative specimens, 41.8% (n = 1337) were positive for at least 1 non-influenza respiratory virus, of which 16.2% (n = 518), 13.4% (n = 428), and 9.6% (n = 308) tested positive for respiratory syncytial virus, rhinovirus, and adenovirus, respectively. CONCLUSIONS: The Government of Vietnam has demonstrated that expanding respiratory viral surveillance by strengthening and building upon an influenza platform is feasible, efficient, and practical.


Assuntos
Monitoramento Epidemiológico , Infecções Respiratórias/epidemiologia , Viroses/epidemiologia , Vírus/isolamento & purificação , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Orthomyxoviridae , Reação em Cadeia da Polimerase em Tempo Real , Infecções Respiratórias/patologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Vietnã/epidemiologia , Viroses/patologia , Vírus/classificação , Adulto Jovem
18.
J Tissue Eng Regen Med ; 12(3): e1691-e1703, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29052350

RESUMO

The idea of rescuing the body self-repair capability lost during evolution is progressively gaining ground in regenerative medicine. In particular, growth factors and bioactive molecules derived from activated platelets emerged as promising therapeutic agents acting as trigger for repair of tissue lesions and restoration of tissue functions. Aim of this study was to assess the potential of a platelet lysate (PL) for human articular cartilage repair considering its activity on progenitor cells and differentiated chondrocytes. PL induced the re-entry in the cell cycle of confluent, growth-arrested dedifferentiated/progenitor cartilage cells. In a cartilage permissive culture environment, differentiated cells also resumed proliferation after exposure to PL. These findings correlated with an up-regulation of the proliferation/survival pathways ERKs and Akt and with an induction of cyclin D1. In short- and long-term cultures of articular cartilage explants, we observed a release of proliferating chondroprogenitors able to differentiate and form an "in vitro" tissue with properties of healthy articular cartilage. Moreover, in cultured cartilage cells, PL induced a hypoxia-inducible factor (HIF-1) alpha increase, its nuclear relocation and the binding to HIF-1 responsive elements. These events were possibly related to the cell proliferation because the HIF-1 inhibitor acriflavine inhibited HIF-1 binding to HIF-1 responsive elements and cell proliferation. Our study demonstrates that PL induces quiescent cartilage cell activation and proliferation leading to new cartilage formation, identifies PL activated pathways playing a role in these processes, and provides a rationale to the application of PL for therapeutic treatment of damaged articular cartilage.


Assuntos
Plaquetas/química , Cartilagem Articular/citologia , Reprogramação Celular , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Idoso , Idoso de 80 Anos ou mais , Cartilagem/metabolismo , Ciclo Celular , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Condrócitos/citologia , Matriz Extracelular/metabolismo , Humanos , Pessoa de Meia-Idade
19.
J Lipids ; 2017: 7170162, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29259829

RESUMO

Free fatty acids (FFAs) were obtained from hydrolyzed virgin coconut oil (VCO) by Candida rugosa lipase (CRL). Four factors' influence on hydrolysis degree (HD) was examined. The best hydrolysis conditions in order to get the highest HD value were determined at VCO to buffer ratio 1 : 5 (w/w), CRL concentration 1.5% (w/w oil), pH 7, and temperature 40°C. After 16 hours' reaction, the HD value achieved 79.64%. FFAs and residual hydrolyzed virgin coconut oil (HVCO) were isolated from the hydrolysis products. They were tested for their antibacterial activity against Gram-negative and Gram-positive bacteria, which can be found in contaminated food and cause food poisoning. FFAs showed their inhibition against Bacillus subtilis (ATCC 11774), Escherichia coli (ATCC 25922), Salmonella enteritidis (ATCC 13076), and Staphylococcus aureus (ATCC 25923) at minimum inhibitory concentration (MIC) of 50%, 60%, 20%, and 40%, respectively. However, VCO and HVCO did not show their antibacterial activity against these tested bacteria.

20.
Artigo em Inglês | MEDLINE | ID: mdl-29209609

RESUMO

Present cell culture medium supplements, in most cases based on animal sera, are not fully satisfactory especially for the in vitro expansion of cells intended for human cell therapy. This paper refers to (i) an heparin-free human platelet lysate (PL) devoid of serum or plasma components (v-PL) and (ii) an heparin-free human serum derived from plasma devoid of PL components (Pl-s) and to their use as single components or in combination in primary or cell line cultures. Human mesenchymal stem cells (MSC) primary cultures were obtained from adipose tissue, bone marrow, and umbilical cord. Human chondrocytes were obtained from articular cartilage biopsies. In general, MSC expanded in the presence of Pl-s alone showed a low or no proliferation in comparison to cells grown with the combination of Pl-s and v-PL. Confluent, growth-arrested cells, either human MSC or human articular chondrocytes, treated with v-PL resumed proliferation, whereas control cultures, not supplemented with v-PL, remained quiescent and did not proliferate. Interestingly, signal transduction pathways distinctive of proliferation were activated also in cells treated with v-PL in the absence of serum, when cell proliferation did not occur, indicating that v-PL could induce the cell re-entry in the cell cycle (cell commitment), but the presence of serum proteins was an absolute requirement for cell proliferation to happen. Indeed, Pl-s alone supported cell growth in constitutively activated cell lines (U-937, HeLa, HaCaT, and V-79) regardless of the co-presence of v-PL. Plasma- and plasma-derived serum were equally able to sustain cell proliferation although, for cells cultured in adhesion, the Pl-s was more efficient than the plasma from which it was derived. In conclusion, the cells expanded in the presence of the new additives maintained their differentiation potential and did not show alterations in their karyotype.

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