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1.
Environ Monit Assess ; 196(3): 280, 2024 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-38368305

RESUMEN

Time constraints, financial limitations, and inadequate tools restrict the flood data collection in undeveloped countries, especially in the Asian and African regions. Engaging citizens in data collection and contribution has the potential to overcome these challenges. This research demonstrates the applicability of citizen science for gathering flood risk-related data on residential flooding, land use information, and flood damage to paddy fields for the Bui River Basin in Vietnam. Locals living in or around flood-affected areas participated in data collection campaigns as citizen scientists using self-investigation or investigation with a data collection app, a web form, and paper forms. We developed a community-based rainfall monitoring network in the study area using low-cost rain gauges to draw locals' attention to the citizen science program. Fifty-nine participants contributed 594 completed questionnaires and measurements for four investigated subjects in the first year of implementation. Five citizen scientists were active participants and contributed more than 50 completed questionnaires or measurements, while nearly 50% of citizen scientists participated only one time. We compared the flood risk-related data obtained from citizen scientists with other independent data sources and found that the agreement between the two datasets on flooding points, land use classification, and the flood damage rate to paddy fields was acceptable (overall agreement above 73%). Rainfall monitoring activities encouraged the participants to proactively update data on flood events and land use situations during the data collection campaign. The study's outcomes demonstrate that citizen science can help to fill the gap in flood data in data-scarce areas.


Asunto(s)
Inundaciones , Ríos , Humanos , Vietnam , Monitoreo del Ambiente , Encuestas y Cuestionarios
2.
Molecules ; 28(22)2023 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-38005345

RESUMEN

Thickener, also known as a gelling agent, is a critical component of lubricating greases. The most critical property of thickener, temperature resistance, is determined by the molecular structure of the compounds. Currently, all high-temperature-resistant thickeners are based on 12-hydroxystearic acid, which is exclusively produced from castor oil. Since castor oil is also an important reagent for other processes, finding a sustainable alternative to 12-hydroxystearic acid has significant economic implications. This study synthesises an alternative thickener from abundant agricultural waste, cashew nut shell liquor (CNSL). The synthesis and separation procedure contains three steps: (i) forming and separating calcium anacardate by precipitation, (ii) forming and separating anacardic acid (iii) forming lithium anacardate. The obtained lithium anacardate can be used as a thickener for lubricating grease. It was found that the recovery of anacardic acid was around 80%. The optimal reaction temperature and time conditions for lithium anacardate were 100 °C and 1 h, respectively. The method provides an economical alternative to castor and other vegetable oils. The procedure presents a simple pathway to produce the precursor for the lubricating grease from agricultural waste. The first reaction step can be combined with the existing distillation of cashew nut shell processing. An effective application can promote CNSL to a sustainable feedstock for green chemistry. The process can also be combined with recycled lithium from the spent batteries to improve the sustainability of the battery industry.

3.
Brain ; 140(3): 582-598, 2017 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-28137726

RESUMEN

New research suggests that common pathways are altered in many neurodevelopmental disorders including autism spectrum disorder; however, little is known about early molecular events that contribute to the pathology of these diseases. The study of monogenic, neurodevelopmental disorders with a high incidence of autistic behaviours, such as fragile X syndrome, has the potential to identify genes and pathways that are dysregulated in autism spectrum disorder as well as fragile X syndrome. In vitro generation of human disease-relevant cell types provides the ability to investigate aspects of disease that are impossible to study in patients or animal models. Differentiation of human pluripotent stem cells recapitulates development of the neocortex, an area affected in both fragile X syndrome and autism spectrum disorder. We have generated induced human pluripotent stem cells from several individuals clinically diagnosed with fragile X syndrome and autism spectrum disorder. When differentiated to dorsal forebrain cell fates, our fragile X syndrome human pluripotent stem cell lines exhibited reproducible aberrant neurogenic phenotypes. Using global gene expression and DNA methylation profiling, we have analysed the early stages of neurogenesis in fragile X syndrome human pluripotent stem cells. We discovered aberrant DNA methylation patterns at specific genomic regions in fragile X syndrome cells, and identified dysregulated gene- and network-level correlates of fragile X syndrome that are associated with developmental signalling, cell migration, and neuronal maturation. Integration of our gene expression and epigenetic analysis identified altered epigenetic-mediated transcriptional regulation of a distinct set of genes in fragile X syndrome. These fragile X syndrome-aberrant networks are significantly enriched for genes associated with autism spectrum disorder, giving support to the idea that underlying similarities exist among these neurodevelopmental diseases.


Asunto(s)
Diferenciación Celular/genética , Proteína de la Discapacidad Intelectual del Síndrome del Cromosoma X Frágil/genética , Síndrome del Cromosoma X Frágil/patología , Regulación de la Expresión Génica/genética , Modelos Biológicos , Células Madre Pluripotentes/fisiología , Animales , Trastorno del Espectro Autista/genética , Trastorno del Espectro Autista/patología , Movimiento Celular/genética , Células Cultivadas , Metilación de ADN/genética , Feto , Síndrome del Cromosoma X Frágil/genética , Redes Reguladoras de Genes , Humanos , Masculino , Ratones , Neurogénesis , Transfección , Repeticiones de Trinucleótidos/genética
4.
Nat Methods ; 8(10): 829-31, 2011 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-21892153

RESUMEN

For some highly endangered species there are too few reproductively capable animals to maintain adequate genetic diversity, and extraordinary measures are necessary to prevent extinction. We report generation of induced pluripotent stem cells (iPSCs) from two endangered species: a primate, the drill, Mandrillus leucophaeus and the nearly extinct northern white rhinoceros, Ceratotherium simum cottoni. iPSCs may eventually facilitate reintroduction of genetic material into breeding populations.


Asunto(s)
Especies en Peligro de Extinción , Células Madre Pluripotentes Inducidas/citología , Mandrillus , Perisodáctilos , Animales , Especificidad de la Especie
5.
BMC Pregnancy Childbirth ; 14: 8, 2014 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-24401012

RESUMEN

BACKGROUND: Antenatal anaemia, iron deficiency and common mental disorders (CMD) are prevalent in low- and middle-income countries. The aim of this study was to examine the direct and indirect effects of antenatal exposures to these risks and infant motor development. METHODS: A cohort of women who were pregnant with a single foetus and between 12 and 20 weeks pregnant in 50 randomly-selected rural communes in Ha Nam province was recruited. Participants provided data twice during pregnancy (early and late gestation) and twice after giving birth (8 weeks and 6 months postpartum). The Edinburgh Postnatal Depression Scale was used at all four data collection waves to detect CMD (score ≥ 4). Maternal anaemia (Hb < 11 g/dL) and iron deficiency (ferritin < 15 ng/mL) were evaluated at early and late gestation. Infants' motor development was assessed by the Bayley of Infant and Toddler Development Motor Scales (BSID-M) at the age of six months. Direct and indirect effects of the exposures on the outcome were examined with Path analysis. RESULTS: In total, 497 of 523 (97%) eligible pregnant women were recruited and 418 mother-infant pairs provided complete data and were included in the analyses. The prevalence of anaemia was 21.5% in early pregnancy and 24.4% in late pregnancy. There was 4.1% iron deficiency at early pregnancy and 48.2% at late pregnancy. Clinically significant symptoms of CMD were apparent among 40% women in early pregnancy and 28% in late pregnancy. There were direct adverse effects on infant BSID-M scores at 6 months of age due to antenatal anaemia in late pregnancy (an estimated mean reduction of 2.61 points, 95% Confidence Interval, CI, 0.57 to 4.65) and CMD in early pregnancy (7.13 points, 95% CI 3.13 to 11.13). Iron deficiency and anaemia in early pregnancy were indirectly related to the outcome via anaemia during late pregnancy. CONCLUSIONS: Antenatal anaemia, iron deficiency, and CMD have a negative impact on subsequent infant motor development. These findings highlight the need to improve the quality of antenatal care when developing interventions for pregnant women that aim to optimise early childhood development in low- and middle-income countries.


Asunto(s)
Anemia/complicaciones , Desarrollo Infantil/fisiología , Deficiencias de Hierro , Trastornos Mentales/complicaciones , Destreza Motora/fisiología , Efectos Tardíos de la Exposición Prenatal/fisiopatología , Adulto , Anemia/sangre , Femenino , Ferritinas/sangre , Hemoglobinas/metabolismo , Humanos , Lactante , Embarazo , Efectos Tardíos de la Exposición Prenatal/etiología , Estudios Prospectivos , Escalas de Valoración Psiquiátrica , Población Rural , Factores de Tiempo , Vietnam , Adulto Joven
6.
PLoS One ; 19(6): e0303354, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38843274

RESUMEN

BACKGROUND: Vietnam is experiencing an increasing prevalence of hypertension in its adult population. In addition to medical therapy, modifying adverse lifestyle practices is important for effective blood pressure control. There are limited data on unhealthy lifestyle practices in patients with chronic diseases, however, particularly among hypertensive patients living in rural Vietnam. Our study objectives were to examine the prevalence of unhealthy lifestyle practices and associated factors among rural Vietnamese adults with uncontrolled hypertension. METHODS: Data from the baseline survey of a cluster randomized trial among hypertensive Vietnamese adults (2017-2022) were utilized. Information on unhealthy lifestyle practices including smoking, excessive alcohol consumption, physical inactivity, and inadequate fruit and vegetable intake was collected from study participants. The primary study outcome was having ≥2 unhealthy lifestyle practices. A multivariable logistic regression model was used to examine factors associated with the primary study outcome. RESULTS: The mean age of the 671 patients was 67 years and 45.0% were men. Nearly three out of every four participants had one or fewer unhealthy practices, 24.0% had two, and 3.3% had three or all four unhealthy lifestyle practices. Men, individuals who did unpaid work or were unemployed, and individuals with hypertension level III were more likely to have ≥2 unhealthy lifestyle practices, whereas individuals with higher education were less likely to have ≥2 unhealthy lifestyle practices compared with respective comparison groups. CONCLUSIONS: We observed a high prevalence of unhealthy lifestyle practices among rural Vietnamese patients with uncontrolled hypertension. Several demographic factors were associated with a greater number of unhealthy lifestyle practices. Newer interventions and educational programs encouraging lifestyle modification practices are needed to control hypertension among adults living in rural settings of Vietnam.


Asunto(s)
Hipertensión , Estilo de Vida , Humanos , Hipertensión/epidemiología , Masculino , Femenino , Vietnam/epidemiología , Persona de Mediana Edad , Anciano , Población Rural/estadística & datos numéricos , Adulto , Consumo de Bebidas Alcohólicas/epidemiología , Prevalencia , Factores de Riesgo , Fumar/epidemiología
7.
Mathematica (N Y) ; 2(3): 523-582, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37780079

RESUMEN

In supersingular isogeny-based cryptography, the path-finding problem reduces to the endomorphism ring problem. Can path-finding be reduced to knowing just one endomorphism? It is known that a small degree endomorphism enables polynomial-time path-finding and endomorphism ring computation (in: Love and Boneh, ANTS XIV-Proceedings of the Fourteenth Algorithmic Number Theory Symposium, volume 4 of Open Book Ser. Math. Sci. Publ., Berkeley, 2020). An endomorphism gives an explicit orientation of a supersingular elliptic curve. In this paper, we use the volcano structure of the oriented supersingular isogeny graph to take ascending/descending/horizontal steps on the graph and deduce path-finding algorithms to an initial curve. Each altitude of the volcano corresponds to a unique quadratic order, called the primitive order. We introduce a new hard problem of computing the primitive order given an arbitrary endomorphism on the curve, and we also provide a sub-exponential quantum algorithm for solving it. In concurrent work (in: Wesolowski, Advances in cryptology-EUROCRYPT 2022, volume 13277 of Lecture Notes in Computer Science. Springer, Cham, 2022), it was shown that the endomorphism ring problem in the presence of one endomorphism with known primitive order reduces to a vectorization problem, implying path-finding algorithms. Our path-finding algorithms are more general in the sense that we don't assume the knowledge of the primitive order associated with the endomorphism.

8.
Mycobiology ; 51(4): 246-255, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37711987

RESUMEN

Genus Penicillium comprising the most important and extensively studied fungi has been well-known as a rich source of secondary metabolites. Our study aimed to analyze and investigate biological activities, including in vitro anti-cancer, anti-inflammatory and anti-diabetic properties, of metabolites from a marine-derived fungus belonging to P. levitum. The chemical compounds in the culture broth of P. levitum strain N33.2 were extracted with ethyl acetate. Followingly, chemical analysis of the extract leaded to the isolation of three ergostane-type steroid components, namely cerevisterol (1), ergosterol peroxide (2), and (3ß,5α,22E)-ergosta-6,8(14),22-triene-3,5-diol (3). Among these, (3) was the most potent cytotoxic against human cancer cell lines Hep-G2, A549 and MCF-7 with IC50 values of 2.89, 18.51, and 16.47 µg/mL, respectively, while the compound (1) showed no significant effect against tested cancer cells. Anti-inflammatory properties of purified compounds were evaluated based on NO-production in LPS-induced murine RAW264.7 macrophages. As a result, tested compounds performed diverse inhibitory effects on NO production by the macrophages, with the most significant inhibition rate of 81.37 ± 1.35% at 25 µg/mL by the compound (2). Interestingly, compounds (2) and (3) exhibited inhibitory activities against pancreatic lipase and α-glucosidase enzymes in vitro assays. Our study brought out new data concerning the chemical properties and biological activities of isolated steroids from a P. levitum fungus.

9.
Artículo en Inglés | MEDLINE | ID: mdl-35457636

RESUMEN

Maternity protection is a normative fundamental human right that enables women to combine their productive and reproductive roles, including breastfeeding. The aim of this study is to examine the uptake of Vietnam's maternity protection policy in terms of entitlements and awareness, perceptions, and gaps in implementation through the lens of formally employed women. In this mixed methods study, we interviewed 494 formally employed female workers, among whom 107 were pregnant and 387 were mothers of infants and conducted in-depth interviews with a subset of these women (n = 39). Of the 494 women interviewed, 268 (54.3%) were working in blue-collar jobs and more than 90% were contributing to the public social insurance fund. Among the 387 mothers on paid maternity leave, 51 (13.2%) did not receive cash entitlements during their leave. Among the 182 mothers with infants aged 6-11 months, 30 (16.5%) returned to work before accruing 180 days of maternity leave. Of 121 women who had returned to work, 26 (21.5%) did not receive a one-hour paid break every day to express breastmilk, relax, or breastfeed, and 46 (38.0%) worked the same or more hours per day than before maternity leave. Although most women perceived maternity leave as beneficial for the child's health (92.5%), mother's health (91.5%), family (86.2%), and society (90.7%), fewer women perceived it as beneficial for their income (59.5%), career (46.4%), and employers (30.4%). Not all formally employed women were aware of their maternity protection rights: women were more likely to mention the six-month paid maternity leave (78.7%) and one-hour nursing break (62.3%) than the other nine entitlements (2.0-35.0%). In-depth interviews with pregnant women and mothers of infants supported findings from the quantitative survey. In conclusion, although Vietnam's maternity protection policy helps protect the rights of women and children, our study identified implementation gaps that limit its effectiveness. To ensure that all women and their families can fully benefit from maternity protection, there is a need to increase awareness of the full set of maternity entitlements, strengthen enforcement of existing policies, and expand entitlements to the informal sector.


Asunto(s)
Lactancia Materna , Madres , Niño , Empleo , Femenino , Humanos , Lactante , Sector Informal , Masculino , Embarazo , Vietnam
10.
Artículo en Inglés | MEDLINE | ID: mdl-35409448

RESUMEN

Background: The infodemic has been co-existing with the COVID-19 pandemic with an influx of misinformation and conspiracy theories. These affect people's psychological health and adherence to preventive measures. eHealth literacy (eHEALS) may help with alleviating the negative effects of the infodemic. As nursing students are future healthcare professionals, having adequate eHEALS skills is critically important in their clinical practice, safety, and health. This study aimed to (1) explore the eHEALS level and its associated factors, and (2) examine the associations of eHEALS with preventive behaviors, fear of COVID-19 (FCV-19S), anxiety, and depression among nursing students. Methods: We surveyed 1851 nursing students from 7 April to 31 May 2020 from eight universities across Vietnam. Data were collected, including demographic characteristics, eHEALS, adherence to preventive behaviors (handwashing, mask-wearing, physical distancing), FCV-19S, anxiety, and depression. Linear and logistic regression analyses were performed appropriately to examine associations. Results: The mean score of eHEALS was 31.4 ± 4.4. The eHEALS score was significantly higher in males (unstandardized regression coefficient, B, 0.94; 95% confidence interval, 95% CI, 0.15 to 1.73; p = 0.019), and students with a better ability to pay for medication (B, 0.79; 95% CI, 0.39 to 1.19; p < 0.001), as compared to their counterparts. Nursing students with a higher eHEALS score had a higher likelihood of adhering to hand-washing (odds ratio, OR, 1.18; 95% CI, 1.15 to 1.22; p < 0.001), mask-wearing (OR, 1.15; 95% CI, 1.12 to 1.19; p < 0.001), keeping a safe physical distance (OR, 1.20; 95% CI, 1.15 to 1.25; p < 0.001), and had a lower anxiety likelihood (OR, 0.95; 95% CI, 0.92 to 0.99; p = 0.011). Conclusions: Nursing students who were men and with better ability to pay for medication had higher eHEALS scores. Those with higher eHEALS scores had better adherence to preventive measures, and better psychological health. The development of strategies to improve eHEALS of nursing students may contribute to COVID-19 containment and improve their psychological health.


Asunto(s)
COVID-19 , Bachillerato en Enfermería , Alfabetización en Salud , Estudiantes de Enfermería , Telemedicina , Ansiedad/epidemiología , COVID-19/epidemiología , COVID-19/prevención & control , Estudios Transversales , Depresión/epidemiología , Miedo , Humanos , Masculino , Pandemias/prevención & control , SARS-CoV-2
11.
Nutrients ; 13(8)2021 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-34445044

RESUMEN

BACKGROUND: The promotion of breastmilk substitutes (BMS) is an important barrier to successful breastfeeding. OBJECTIVE: To examine the enactment and implementation of the Code of Marketing of Breast-Milk Substitutes (the Code) in Vietnam with a focus on marketing practices by the baby food industry and perceptions of caregivers, health workers, and policy makers. METHODS: From May to July 2020, we conducted a mixed-method, cross-sectional study including a survey of 268 pregnant women and 726 mothers of infants aged 0-11 months and in-depth interviews with a subset of interviewed women (n = 39), policy makers, media executives, and health workers (n = 31). RESULTS: In the previous 30 days, two mothers (out of 726) participating in the quantitative survey reported that health workers had recommended BMS, at private hospitals in both cases. In-depth interviews with health workers showed that hospitals have internal procedures to prevent the promotion of BMS by health workers. However, companies employed representatives to promote products not covered under the Code (e.g., commercial milk formula for pregnant women) at antenatal care visits and by gaining contact information from women and using this information to promote BMS outside the hospital, often on social media. In the 30 days preceding the survey, one-fifth of pregnant women were exposed to promotions of commercial milk formula for pregnant women and 7.1% to promotions of BMS. Among mothers of infants, 7.3% and 10.7% of respondents with infants aged 0-5 and 6-11 months, respectively, were exposed to some form of BMS promotion in the past 30 days. Around the time of birth, parents commonly brought BMS to maternity facilities (52.5%) or purchased it nearby (35.4%). CONCLUSIONS: Although Vietnam has a strong regulatory environment for the protection, promotion, and support of breastfeeding, there are implementation, monitoring, and enforcement gaps. Stronger enforcement of national policies to regulate the presence of BMS industry representatives in health facilities-both public and private-and the promotion of BMS products on digital platforms are needed.


Asunto(s)
Cuidadores/psicología , Industria de Alimentos/métodos , Personal de Salud/psicología , Mercadotecnía/métodos , Sustitutos de la Leche/legislación & jurisprudencia , Lactancia Materna/psicología , Estudios Transversales , Femenino , Industria de Alimentos/legislación & jurisprudencia , Implementación de Plan de Salud , Humanos , Lactante , Recién Nacido , Mercadotecnía/legislación & jurisprudencia , Madres/psicología , Política Nutricional , Percepción , Embarazo , Investigación Cualitativa , Vietnam
12.
Nat Commun ; 11(1): 1070, 2020 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-32081845

RESUMEN

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

13.
Front Pharmacol ; 9: 656, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29977205

RESUMEN

Background: Patient adherence to cardioprotective medications improves outcomes of acute coronary syndrome (ACS), but few adherence-enhancing interventions have been tested in low-income and middle-income countries. Objectives: We aimed to assess whether a pharmacist-led intervention enhances medication adherence in patients with ACS and reduces mortality and hospital readmission. Methods: We conducted a randomized controlled trial in Vietnam. Patients with ACS were recruited, randomized to the intervention or usual care prior to discharge, and followed 3 months after discharge. Intervention patients received educational and behavioral interventions by a pharmacist. Primary outcome was the proportion of adherent patients 1 month after discharge. Adherence was a combined measure of self-reported adherence (the 8-item Morisky Medication Adherence Scale) and obtaining repeat prescriptions on time. Secondary outcomes were (1) the proportion of patients adherent to medication; (2) rates of mortality and hospital readmission; and (3) change in quality of life from baseline assessed with the European Quality of Life Questionnaire - 5 Dimensions - 3 Levels at 3 months after discharge. Logistic regression was used to analyze data. Registration: ClinicalTrials.gov (NCT02787941). Results: Overall, 166 patients (87 control, 79 intervention) were included (mean age 61.2 years, 73% male). In the analysis excluding patients from the intervention group who did not receive the intervention and excluding all patients who withdrew, were lost to follow-up, died or were readmitted to hospital, a greater proportion of patients were adherent in the intervention compared with the control at 1 month (90.0% vs. 76.5%; adjusted OR = 2.77; 95% CI, 1.01-7.62) and at 3 months after discharge (90.2% vs. 77.0%; adjusted OR = 3.68; 95% CI, 1.14-11.88). There was no significant difference in median change of EQ-5D-3L index values between intervention and control [0.000 (0.000; 0.275) vs. 0.234 (0.000; 0.379); p = 0.081]. Rates of mortality, readmission, or both were 0.8, 10.3, or 11.1%, respectively; with no significant differences between the 2 groups. Conclusion: Pharmacist-led interventions increased patient adherence to medication regimens by over 13% in the first 3 months after ACS hospital discharge, but not quality of life, mortality and readmission. These results are promising but should be tested in other settings prior to broader dissemination.

14.
PLoS One ; 12(3): e0173373, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28278187

RESUMEN

Gestational diabetes mellitus (GDM), which complicates up to 20% of all pregnancies, is associated with low-grade maternal inflammation and peripheral insulin resistance. Sterile inflammation and infection are key mediators of this inflammation and peripheral insulin resistance. Resveratrol, a stilbene-type phytophenol, has been implicated to exert beneficial properties including potent anti-inflammatory and antidiabetic effects in non-pregnant humans and experimental animal models of GDM. However, studies showing the effects of resveratrol on inflammation and insulin resistance associated with GDM in human tissues have been limited. In this study, human placenta, adipose (omental and subcutaneous) tissue and skeletal muscle were stimulated with pro-inflammatory cytokines TNF-α and IL-1ß, the bacterial product lipopolysaccharide (LPS) and the synthetic viral dsRNA analogue polyinosinic:polycytidylic acid (poly(I:C)) to induce a GDM-like model. Treatment with resveratrol significantly reduced the expression and secretion of pro-inflammatory cytokines IL-6, IL-1α, IL-1ß and pro-inflammatory chemokines IL-8 and MCP-1 in human placenta and omental and subcutaneous adipose tissue. Resveratrol also significantly restored the defects in the insulin signalling pathway and glucose uptake induced by TNF-α, LPS and poly(I:C). Collectively, these findings suggest that resveratrol reduces inflammation and insulin resistance induced by chemical and microbial products. Resveratrol may be a useful preventative therapeutic for pregnancies complicated by inflammation and insulin resistance, like GDM.


Asunto(s)
Tejido Adiposo/efectos de los fármacos , Resistencia a la Insulina , Músculo Esquelético/efectos de los fármacos , Placenta/efectos de los fármacos , Estilbenos/farmacología , Tejido Adiposo/metabolismo , Tejido Adiposo/microbiología , Tejido Adiposo/patología , Diabetes Gestacional/metabolismo , Diabetes Gestacional/microbiología , Diabetes Gestacional/patología , Femenino , Humanos , Lactante , Inflamación/metabolismo , Inflamación/microbiología , Insulina/metabolismo , Músculo Esquelético/metabolismo , Músculo Esquelético/microbiología , Músculo Esquelético/patología , Placenta/metabolismo , Placenta/microbiología , Placenta/patología , Embarazo , Resveratrol , Transducción de Señal/efectos de los fármacos
15.
Drug Alcohol Depend ; 150: 46-53, 2015 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-25765480

RESUMEN

OBJECTIVE: Women who sell sex and use drugs have dual risks for HIV infection. Despite increasing reports of drug use among female sex workers (FSW) in Vietnam, FSW HIV interventions remain focused mainly on sexual risk reduction. We assessed the impact of drug use and inconsistent condom use on HIV infection among FSW in Vietnam, which few studies have quantified. METHODS: We surveyed 5298 women aged ≥18 years who had sold sex in the past month from ten geographically dispersed provinces. We performed multivariate logistic regression on data from provinces with high (≥10%) or low (<10%) HIV prevalence among FSW. RESULTS: Compared to FSW who never used illicit drugs, the odds of HIV infection among FSW who had ever injected drugs and those who reported non-injection drug use were 3.44 (CI 2.32-5.09) and 1.76 (CI 1.14-2.71), respectively, in high-prevalence provinces. FSW who always used condoms with clients had lower odds of HIV infection than those who did not (AOR=0.71; CI 0.52-0.98). In low-prevalence provinces lifetime injection drug use (AOR 22.05, CI 12.00-40.49), but not non-injecting drug use or inconsistent condom use, was significantly associated with HIV infection. CONCLUSIONS: Because injection drug use and inconsistent condom use were key risk factors for HIV infection in high-prevalence provinces, drug injection risk reduction should be as much a focus of HIV prevention as sexual risk reduction. Where HIV prevalence remains low in FSW, a more general emphasis on harm reduction for all drug users will benefit FSW.


Asunto(s)
Infecciones por VIH/epidemiología , Trabajadores Sexuales/psicología , Abuso de Sustancias por Vía Intravenosa/epidemiología , Trastornos Relacionados con Sustancias/epidemiología , Adolescente , Adulto , Condones , Consumidores de Drogas/psicología , Femenino , Humanos , Persona de Mediana Edad , Prevalencia , Factores de Riesgo , Sexo Inseguro/estadística & datos numéricos , Vietnam/epidemiología , Adulto Joven
16.
Sci Rep ; 5: 13317, 2015 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-26304831

RESUMEN

Many studies have suggested the significance of glycosyltransferase-mediated macromolecule glycosylation in the regulation of pluripotent states in human pluripotent stem cells (hPSCs). Here, we observed that the sialyltransferase ST6GAL1 was preferentially expressed in undifferentiated hPSCs compared to non-pluripotent cells. A lectin which preferentially recognizes α-2,6 sialylated galactosides showed strong binding reactivity with undifferentiated hPSCs and their glycoproteins, and did so to a much lesser extent with differentiated cells. In addition, downregulation of ST6GAL1 in undifferentiated hPSCs led to a decrease in POU5F1 (also known as OCT4) protein and significantly altered the expression of many genes that orchestrate cell morphogenesis during differentiation. The induction of cellular pluripotency in somatic cells was substantially impeded by the shRNA-mediated suppression of ST6GAL1, partially through interference with the expression of endogenous POU5F1 and SOX2. Targeting ST6GAL1 activity with a sialyltransferase inhibitor during cell reprogramming resulted in a dose-dependent reduction in the generation of human induced pluripotent stem cells (hiPSCs). Collectively, our data indicate that ST6GAL1 plays an important role in the regulation of pluripotency and differentiation in hPSCs, and the pluripotent state in human cells can be modulated using pharmacological tools to target sialyltransferase activity.


Asunto(s)
Antígenos CD/metabolismo , Diferenciación Celular/fisiología , Lectinas/metabolismo , Ácido N-Acetilneuramínico/metabolismo , Células Madre Pluripotentes/citología , Células Madre Pluripotentes/fisiología , Sialiltransferasas/metabolismo , Activación Enzimática , Regulación del Desarrollo de la Expresión Génica/fisiología , Regulación Enzimológica de la Expresión Génica/fisiología , Glicosilación , Humanos
17.
Nat Commun ; 5: 4430, 2014 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-25034944

RESUMEN

Down's syndrome (DS), caused by trisomy of human chromosome 21, is the most common genetic cause of intellectual disability. Here we use induced pluripotent stem cells (iPSCs) derived from DS patients to identify a role for astrocytes in DS pathogenesis. DS astroglia exhibit higher levels of reactive oxygen species and lower levels of synaptogenic molecules. Astrocyte-conditioned medium collected from DS astroglia causes toxicity to neurons, and fails to promote neuronal ion channel maturation and synapse formation. Transplantation studies show that DS astroglia do not promote neurogenesis of endogenous neural stem cells in vivo. We also observed abnormal gene expression profiles from DS astroglia. Finally, we show that the FDA-approved antibiotic drug, minocycline, partially corrects the pathological phenotypes of DS astroglia by specifically modulating the expression of S100B, GFAP, inducible nitric oxide synthase, and thrombospondins 1 and 2 in DS astroglia. Our studies shed light on the pathogenesis and possible treatment of DS by targeting astrocytes with a clinically available drug.


Asunto(s)
Astrocitos/fisiología , Síndrome de Down/fisiopatología , Células Madre Pluripotentes Inducidas/fisiología , Animales , Astrocitos/efectos de los fármacos , Estudios de Casos y Controles , Diferenciación Celular , Supervivencia Celular , Trasplante de Células/métodos , Medios de Cultivo Condicionados/farmacología , Síndrome de Down/genética , Perfilación de la Expresión Génica , Proteína Ácida Fibrilar de la Glía/metabolismo , Proteínas de Homeodominio/genética , Humanos , Células Madre Pluripotentes Inducidas/trasplante , Ratones Endogámicos C57BL , Ratones Mutantes , Minociclina/farmacología , Células-Madre Neurales/fisiología , Neuronas/citología , Neuronas/fisiología , Óxido Nítrico Sintasa de Tipo II/genética , Óxido Nítrico Sintasa de Tipo II/metabolismo , Subunidad beta de la Proteína de Unión al Calcio S100/genética , Subunidad beta de la Proteína de Unión al Calcio S100/metabolismo , Trombospondina 1/metabolismo , Trombospondinas/metabolismo
18.
J Vis Exp ; (57): e3177, 2011 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-22158256

RESUMEN

Pluripotent stem cells (PSCs) have the unique characteristic that they can differentiate into cells from all three germ layers. This makes them a potentially valuable tool for the treatment of many different diseases. With the advent of induced pluripotent stem cells (iPSCs) and continuing research with human embryonic stem cells (hESCs) there is a need for assays that can demonstrate that a particular cell line is pluripotent. Germline transmission has been the gold standard for demonstrating the pluripotence of mouse embryonic stem cell (mESC) lines(1,2,3). Using this assay, researchers can show that a mESC line can make all cell types in the embryo including germ cells(4). With the generation of human ESC lines(5,6), the appropriate assay to prove pluripotence of these cells was unclear since human ESCs cannot be tested for germline transmission. As a surrogate, the teratoma assay is currently used to demonstrate the pluripotency of human pluripotent stem cells (hPSCs)(7,8,9). Though this assay has recently come under scrutiny and new technologies are being actively explored, the teratoma assay is the current gold standard(7). In this assay, the cells in question are injected into an immune compromised mouse. If the cells are pluripotent, a teratoma will eventually develop and sections of the tumor will show tissues from all 3 germ layers(10). In the teratoma assay, hPSCs can be injected into different areas of the mouse. The most common injection sites include the testis capsule, the kidney capsule, the liver; or into the leg either subcutaneously or intramuscularly(11). Here we describe a robust protocol for the generation of teratomas from hPSCs using the testis capsule as the site for tumor growth.


Asunto(s)
Transformación Celular Neoplásica/patología , Células Madre Neoplásicas/patología , Células Madre Pluripotentes/patología , Teratoma/patología , Neoplasias Testiculares/patología , Animales , Masculino , Ratones , Ratones SCID
19.
PLoS One ; 6(8): e23018, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21857983

RESUMEN

Human pluripotent stem cell (hPSC) lines have been considered to be homogeneously euploid. Here we report that normal hPSC--including induced pluripotent--lines are karyotypic mosaics of euploid cells intermixed with many cells showing non-clonal aneuploidies as identified by chromosome counting, spectral karyotyping (SKY) and fluorescent in situ hybridization (FISH) of interphase/non-mitotic cells. This mosaic aneuploidy resembles that observed in progenitor cells of the developing brain and preimplantation embryos, suggesting that it is a normal, rather than pathological, feature of stem cell lines. The karyotypic heterogeneity generated by mosaic aneuploidy may contribute to the reported functional and phenotypic heterogeneity of hPSCs lines, as well as their therapeutic efficacy and safety following transplantation.


Asunto(s)
Aneuploidia , Células Madre Pluripotentes/citología , Células Madre Pluripotentes/metabolismo , Animales , Técnicas de Cultivo de Célula , Línea Celular , Femenino , Humanos , Hibridación Fluorescente in Situ , Cariotipificación , Ratones , Cariotipificación Espectral
20.
Cell Res ; 21(11): 1551-63, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21894191

RESUMEN

Rapid and dependable methods for isolating human pluripotent stem cell (hPSC) populations are urgently needed for quality control in basic research and in cell-based therapy applications. Using lectin arrays, we analyzed glycoproteins extracted from 26 hPSC samples and 22 differentiated cell samples, and identified a small group of lectins with distinctive binding signatures that were sufficient to distinguish hPSCs from a variety of non-pluripotent cell types. These specific biomarkers were shared by all the 12 human embryonic stem cell and the 14 human induced pluripotent stem cell samples examined, regardless of the laboratory of origin, the culture conditions, the somatic cell type reprogrammed, or the reprogramming method used. We demonstrated a practical application of specific lectin binding by detecting hPSCs within a differentiated cell population with lectin-mediated staining followed by fluorescence microscopy and flow cytometry, and by enriching and purging viable hPSCs from mixed cell populations using lectin-mediated cell separation. Global gene expression analysis showed pluripotency-associated differential expression of specific fucosyltransferases and sialyltransferases, which may underlie these differences in protein glycosylation and lectin binding. Taken together, our results show that protein glycosylation differs considerably between pluripotent and non-pluripotent cells, and demonstrate that lectins may be used as biomarkers to monitor pluripotency in stem cell populations and for removal of viable hPSCs from mixed cell populations.


Asunto(s)
Biomarcadores/metabolismo , Glicómica , Lectinas/metabolismo , Células Madre Pluripotentes/citología , Células Madre Pluripotentes/metabolismo , Biotina/química , Biotina/metabolismo , Separación Celular , Células Cultivadas , Células Madre Embrionarias/citología , Fucosiltransferasas/metabolismo , Perfilación de la Expresión Génica , Glicosilación , Humanos , Células Madre Pluripotentes Inducidas/citología , Lectinas/química , Análisis por Matrices de Proteínas , Unión Proteica , Sialiltransferasas/metabolismo
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