Treatment non-adherence among methadone maintenance patients and associated factors: a multicenter, cross-sectional study in Vietnam.

OBJECTIVE: This multicenter, cross-sectional study was conducted to investigate the prevalence of treatment non-adherence and its associated factors among methadone maintenance patients in Vietnam. METHODS: This secondary data analysis was conducted using the data from a previous study. Six hundred patients were interviewed face-to-face to collect data on their demographic characteristics and social support. Information about the treatment characteristics and patients' non-adherence was gathered from medical records and books monitoring their treatment process. Treatment non-adherence was defined as missing at least one methadone dose in the last three months. RESULTS: The overall prevalence of non-adherence was 45.7%. The average social support score of patients who completely adhered to treatment was significantly higher than that of those who did not (p < 0.001). In the multivariate logistic regression model, for each one-unit increase in social support (one score), treatment time (a year), and patient's monthly income (one million Vietnam dongs), the odds of non-adherence decreased by 28% (aOR = 0.72, 95%CI 0.59-0.88, p = 0.002), 15% (aOR = 0.85, 95%CI 0.80-0.91, p < 0.001) and 9% (aOR = 0.91, 95%CI 0.85-0.97, p = 0.004), respectively. Patients living in Son La (a mountainous province) were 1.72 times (95%CI 1.09-2.71) more likely to be non-adherent as compared to those in other areas (p = 0.020). As per univariate analyses, other associated factors could be age, education level, family monthly income, occupation, and opioid relapse (p < 0.001). CONCLUSIONS: A high non-adherence rate was found among Vietnamese methadone maintenance patients. Interventions involving social support, occupation, income, and education are needed to improve their treatment adherence.

A Comprehensive Evaluation of Dioxins and Furans Occurrence in River Sediments from a Secondary Steel Recycling Craft Village in Northern Vietnam.

This first study investigated the presence of dioxins and furans in river sediments around a craft village in Vietnam, focusing on Secondary Steel Recycling. Sediment samples were collected from various locations along the riverbed near the Da Hoi Secondary Steel Recycling village in Bac Ninh province. The analysis was conducted using a HRGC/HRMS-DFS device, detecting a total of 17 dioxin/furan isomers in all samples, with an average total concentration of 288.86 ng/kg d.w. The concentrations of dioxin/furan congeners showed minimal variation among sediment samples, ranging from 253.9 to 344.2 ng/kg d.w. The predominant compounds in the dioxin group were OCDD, while in the furan group, they were 1,2,3,4,6,7,8-HpCDF and OCDF. The chlorine content in the molecule appeared to be closely related to the concentration of dioxins and their percentage distribution. However, the levels of furan isomers did not vary significantly. The distribution of these compounds was not dependent on the flow direction, as they were mainly found in solid waste and are not water-soluble. Although the hepta and octa congeners had high concentrations, when converted to TEQ values, the tetra and penta groups (for dioxins) and the penta and hexa groups (for furans) contributed more to toxicity. Furthermore, the source of dioxins in sediments at Da Hoi does not only originate from steel recycling production activities but also from other combustion sites. The average total toxicity was 10.92 ng TEQ/kg d.w, ranging from 4.99 to 17.88 ng TEQ/kg d.w, which did not exceed the threshold specified in QCVN 43:2017/BTNMT, the National Technical Regulation on Sediment Quality. Nonetheless, these levels are still concerning. The presence of these toxic substances not only impacts aquatic organisms in the sampled water environment but also poses potential health risks to residents living nearby.

Knowledge and attitudes of community pharmacists regarding dementia: A nationwide cross-sectional study in Vietnam.

OBJECTIVE: To investigate Vietnamese community pharmacists' knowledge and attitudes towards dementia. METHODS: 1066 community pharmacists in eight provinces/centrally-governed cities were recruited using a non-probability convenience sampling technique. Their dementia knowledge was measured using a set of 14 questions developed through a literature review. The Approaches to Dementia Questionnaire was used to assess pharmacists' attitudes towards dementia. Cronbach's alpha was 0.88 for the overall questionnaire (0.70 for the knowledge part and 0.81 for the attitude part). RESULTS: Participants were mostly female (74.2%), 20-39 years old (79.1%), and had work experience in pharmacies of less than 10 years (77.0%). Medicines for dementia were available in only 40 community pharmacies (3.8%), including galantamine (3.0%) and donepezil (0.8%). Pharmacists' average knowledge and attitude scores were 8.03 ± 2.61 and 64.81 ± 7.34, respectively. There were considerable differences in pharmacists' knowledge and attitudes between rural and urban areas and among eight provinces (p < 0.001). Higher knowledge and attitude scores were found among those with higher education levels and longer work experience (p < 0.001). Using reliable sources to seek information on dementia, such as books and scientific articles, also helped pharmacists to have better knowledge and more positive attitudes (p < 0.001). There was a positive relationship between knowledge and attitude scores (r = 0.326, p < 0.001). CONCLUSION: Community pharmacists demonstrated moderate levels of knowledge and attitudes towards dementia. Their knowledge about the symptoms of dementia was inadequate. Educational interventions and training programs are urgently needed to enhance their dementia knowledge and attitudes.

Post-stroke depression in Vietnamese patients is associated with decreased sleep quality and increased fatigue: a one-institution cross-sectional analysis.

PURPOSE: This study aimed to determine the prevalence of post-stroke depression (PSD) during the first year and its associated factors, especially focusing on sleep quality and fatigue severity. METHODS: A cross-sectional study was conducted among stroke patients in Vietnam's National Geriatric Hospital. Data were collected by using standardized questionnaires for interviewing and evaluating patients at the research site. Several covariables were presented including demographics, stroke-related characteristics, activities of daily living, post-stroke fatigue, and sleep quality (Pittsburgh Sleep Quality Index [PSQI] scale). PSD was assessed as an outcome variable through the Patient Health Questionnaire-9 scale. To summarize sociodemographic and clinical variables, descriptive statistics were performed. A logistic regression model was used to explore the factors related to PSD. RESULTS: Of 157 patients with stroke, mean age 73.1 (± 9.6), PSD was present in 60 patients (38%). The global score and all PSQI components of participants with PSD showed worse levels than those without depression. Furthermore, the prevalence of PSD was higher in patients with low IADL scores and functional disability at high levels. In the multivariate logistic regression analysis, the patients with PSD showed higher Fatigue Severity Scale (FSS) scores (OR = 4.11; 95% CI = 1.39; 12.19) and higher scores in two domains of the PSQI scale including subjective sleep quality (OR = 3.03; 95% CI = 1.21; 7.58) and sleep disturbance (OR = 5.22; 95% CI = 1.33; 20.47). CONCLUSION: There is a significant prevalence of depression following stroke. Furthermore, post-stroke fatigue and two PSQI scale components (subjective sleep quality and sleep disturbance) were shown to be associated with PSD. This finding may guide early screening and intervention strategies to address depression following stroke.

Information needs of informal caregivers in caring and rehabilitation for dioxin victims in Vietnam.

BACKGROUND: Health outcomes among Agent Orange/dioxin (dioxin) victims are significant due to many individuals requiring daily assistance, informal care, and rehabilitation support. This study aimed to identify the information needs of informal caregivers of dioxin victims in Vietnam. METHODS: A cross-sectional study was conducted in Quynh Phu district, Thai Binh province - an area with a large number of dioxin victims, from June 2019 to June 2020. Quantitative data were collected from 124 caregivers of victims via structured interviews. Qualitative data were collected using semi-structured interview guides with in-depth interviews (IDI) (n = 36) and two focus group discussions (FGD) (n = 12). RESULTS: The results demonstrated that all caregivers of dioxin victims were family members, predominantly older (71.8%), 61.5 years old on average, living on low incomes (87.9%), and were farmers (80.7%). Almost all participants (96.8%) reported having information needs, particularly concerning dioxin's harms, nutrition, dioxin-related policies and rehabilitation, and psychological support for patients. Caregivers reported that they would like to receive information via health staff counselling (85.0%), television (75.0%), and community loudspeaker (65.8%). Notably, the majority of caregivers reported the need for information regarding psychological support (70.0%). These findings are consistent with qualitative data, which identify an urgent need to provide information, especially through health staff and digital resources. CONCLUSION: Many families with dioxin victims lived with little support and information, highlighting their high demand for information about care and rehabilitation. Thus, the healthcare system should promote information support, policy, and psychological support for caregivers and victims. An online support system for caregivers and victims is also recommended.

Experiences and perceptions of dementia in Vietnam and among the Vietnamese diaspora: a systematic review of qualitative studies.

Objectives: This paper aimed to review and synthesise the qualitative research evidence on the experiences and perceptions of dementia in Vietnam and among the Vietnamese diaspora.Methods: Systematic searches were conducted in June 2019 using Medline, Embase, Emcare, PsycINFO and Cochrane electronic databases, as well as grey literature. Keywords and Medical Subject Headings [MeSH terms] for dementia and associated terms were combined with keywords for Vietnam and its provinces. Qualitative research articles published in English or Vietnamese were included to examine evidence on the life experiences of Vietnamese people with dementia using thematic analysis.Results: Our searches resulted in 3,940 papers, from which 21 qualitative research studies were included for final analysis. The majority of research has not been undertaken in Vietnam but with the Vietnamese diaspora in Western countries and has taken a cultural perspective to analyses. Research in Western countries has focused on the need for culturally adapted and culturally sensitive models of care. Emerging themes about the life experiences of Vietnamese people with dementia identified from the studies included: many people do not have diagnostic terms for dementia but use the descriptive language of symptoms; stigma was a reported problem and on occasions can be observed in the descriptive language used for people with dementia; cultural and traditional values create both an opportunity and a barrier, supporting compassion, family care and relaxation, but creating barriers to accessing health services or long-term residential care.Conclusions: This is the first systematic review reporting qualitative evidence on the life experiences of people with dementia in Vietnam and among the Vietnamese diaspora. Future research is needed on the voice of people with dementia themselves and their caregivers particularly in Vietnam, and low and middle-income countries with regards to living with dementia, pathways to care from diagnosis, treatment, care and support, additional social care and preparedness for end of life care for people with dementia.

Opioid relapse and its predictors among methadone maintenance patients: a multicenter, cross-sectional study in Vietnam.

BACKGROUND: Opioid relapse, one of the common and severe problems during methadone maintenance treatment, can give rise to poor treatment outcomes. This study measured the opioid relapse rate and its associated factors among methadone maintenance patients in Vietnam. METHODS: Information about the demographic characteristics and social support of 655 patients was collected through direct interviews. Medical records were used to gather data on treatment characteristics. Relapse was determined via urine opioid test results. RESULTS: The overall relapse rate of patients during treatment was 13.1%. According to the multivariate logistic regression model, living in mountainous areas (adjusted odds ratio (aOR) = 3.63, 95% CI 1.90-7.46) and long duration of drug use in the past (aOR = 1.06, 95% CI 1.03-1.09) were associated with an increase in the odds of opioid relapse. By contrast, living with many family members (aOR = 0.69, 95% CI 0.55-0.85), having longer treatment time (aOR = 0.80, 95% CI 0.73-0.87), and completely adhering to treatment (aOR = 0.38, 95% CI 0.23-0.64) were protective for opioid relapse. As per the univariate analyses, the odds of opioid relapse declined by 25% for each increase of one close friend or relative (OR = 0.75, 95% CI 0.66-0.86). Regarding social support (range score: 0-100), each additional increase of one score was associated with a 1% decrease in the odds of opioid relapse (OR = 0.99, 95% CI 0.98-0.99). Patient sex, education level, occupation type, patient's monthly income, family's monthly income, the number of previous treatments, daily methadone dose, comorbidity, and received antiretroviral therapy were not associated with opioid relapse among patients (p > 0.05). CONCLUSIONS: Residence, the role of family and social support, and treatment adherence should be paid more attention to guarantee and enhance the success of methadone maintenance treatment.

Comprehensive Geriatric Assessment in Older Patients with Diabetes Mellitus in Hanoi, Vietnam.

INTRODUCTION: Comprehensive geriatric assessment (CGA) of older diabetic patients is thought to be of value, but there have been limited studies on the prevalence of impairments in the components of a CGA as well as the relationship between CGA and diabetic control in this group. OBJECTIVE: This study aimed to evaluate the prevalence of components of CGA in older patients with diabetes in National Geriatric Hospital, Hanoi, Vietnam, and determine the association among domains of CGA with measures of diabetic control. METHODS: A cross-sectional study of diabetic outpatients aged ≥60 years at National Geriatric Hospital in Hanoi, Vietnam, recruited over 3 months. The CGA questionnaire includes different assessments consisting of cognitive impairment (using Mini-Cog test), depression (using the 15-item Geriatric Depression Scale), urinary incontinence (using the 3-Incontinence questions), Activities of Daily Living (ADL) dependence, Instrumental Activities of Daily Living (IADL) dependence, high fall risk (using Hendrich II Fall Risk Model), hearing loss (using Whisper test), low visual acuity (using Snellen test), polypharmacy, malnutrition (using the Mini-Nutritional Assessment Short Form), and multiple geriatric conditions (patients had 2 or more geriatric conditions). Multiple logistic regression was used to analyze the association between demographic factors and CGA components with measures of diabetes control. RESULTS: A total of 412 patients were recruited (56.6% female, mean age 71.9 [7.6] years). Prevalence of impairment in components of the CGA was high and highest for vision impairment (94.2%) and multiple geriatric conditions (89.3%). Age <75 years, cognitive impairment, depressive symptom, IADL impairment, and high fall risk were significantly associated with both poor fasting plasma glucose control (>130 mg/dL) and poor HbA1c control (≥7%). CONCLUSIONS: This study highlights that geriatric syndromes are common in older diabetic patients and associated with poorer diabetic control. It suggests CGA may be important to conduct in this group by establishing an interdisciplinary Geriatric health care team.

Impact of pharmacist-initiated educational interventions on improving medication reconciliation practice in geriatric inpatients during hospital admission in Vietnam.

WHAT IS KNOWN AND OBJECTIVE: Unintentional medication discrepancies (UMDs) are common in geriatric patients during care transitions, resulting in frequent undesirable consequences. Medication reconciliation could be a useful practice to prevent or ameliorate UMD. However, this practice in Vietnamese hospitals has not been well established or standardized. This study aims to determine the effect of pharmacist-initiated educational interventions on improving medication reconciliation practice. METHODS: This prospective 6-month pre-and post-study was conducted in two internal medicine wards in a Vietnamese 800-bed public hospital. Pharmacists provided training and short-term support to physicians on medication reconciliation. Primary outcome measures were the proportions of patients with at least one UMD at admission. Secondary outcome measures were the proportions of patients with preventable adverse drug events (pADEs) score ≥0.1 due to these UMDs. Odds ratio and 95% confidence intervals were assessed based on a multivariate logistic regression model. RESULTS AND DISCUSSION: One hundred fifty-two patients were recruited in the pre-intervention phase, and 146 in the post-intervention phase. Following the intervention, the proportion of geriatric patients with ≥1 UMD at admission significantly decreased from 55.3 to 25.3 % (ORadj 0.255, 95% CI: 0.151-0.431). Similarly, the proportion of patients with a pADE ≥0.1 at admission reduced from 44.1 to 11.6% [ORadj 0.188, 95% CI: 0.105-0.340] post-intervention. WHAT IS NEW AND CONCLUSION: Our pharmacist-initiated educational interventions have demonstrated the ability to produce substantial improvement in medication reconciliation practice, reducing UMDs and potential harm. Our approach may provide an alternate option to implement medication reconciliation for jurisdictions with limited healthcare resources.

Implementing clinical pharmacy activities in hospital setting in Vietnam: current status from a national survey.

BACKGROUND: Clinical pharmacy activities have evolved over the past decades contributing to all stages of the patient care process, especially in the hospital setting. However, these practice roles may differ to a significant extent depending on the healthcare policy of countries. In Vietnam, the magnitude of adopting clinical pharmacy activities in hospital settings throughout the country is still unknown since these activities have been implemented. This study aimed to ascertain the current status of clinical pharmacy activities performed within the Vietnamese hospital setting. METHODS: A nation-wide survey was conducted from December 2017 to January 2018. Two online questionnaires, one for the Heads of Pharmacy Department and one for clinical pharmacists, were designed based on the national legal regulations about implementing clinical pharmacy activities in the hospital setting. These questionnaires were sent to all hospitals and healthcare facilities with a department of pharmacy. RESULTS: A total of 560 Heads of Pharmacy and 574 clinical pharmacists participated in the study, representing a response rate of 41.2%. Among the participating hospitals, non-patient specific activities were implemented widely across all hospital classes, with pharmacovigilance, medication information, and standard operating procedures development implemented in ≥88% of all hospitals. In contrast, there was a significant variation in the level of implementation of patient-specific activities among hospital classes. With activities such as medication counselling, monitoring of adverse drug reactions, and obtaining patient's medication histories provided at a considerably lower level in between 49 and 57% of hospitals. CONCLUSION: Clinical pharmacy activities have been initiated in most of the surveyed hospitals. In general, clinical pharmacy is more established in higher-class hospitals in Vietnam. However, the current implementation status is focused on non-patient-specific activities, while patient-oriented activities remained insufficiently established.

Lactobacillus sakei MJM60958 as a Potential Probiotic Alleviated Non-Alcoholic Fatty Liver Disease in Mice Fed a High-Fat Diet by Modulating Lipid Metabolism, Inflammation, and Gut Microbiota.

Non-alcoholic fatty liver disease (NAFLD) is a common liver disease with a rapidly increasing number of cases worldwide. This study aimed to evaluate the effects of Lactobacillus sakei MJM60958 (MJM60958) on NAFLD in vitro and in vivo. In in vitro tests, MJM60958 significantly inhibited lipid accumulation by 46.79% in HepG2 cells stimulated with oleic acid and cholesterol (OA-C). Moreover, MJM60958 showed safe and probiotic characteristics in vitro. In the animal study, MJM60958 administration in a high-fat diet-induced NAFLD mouse model significantly reduced body weight and liver weight, and controlled aspartate aminotransferase (ALT), aspartate transaminase (AST), triglyceride (TG), urea nitrogen (BUN), and uric acid (UA) levels in the blood, which are features of NAFLD. Further, treatment with MJM60958 also reduced steatosis scores in liver tissues, serum leptin and interleukin, and increased serum adiponectin content. Moreover, administration of MJM60958 resulted in a significantly decreased expression of some genes and proteins which are related to lipid accumulation, such as fatty acid synthase (FAS), acetyl-CoA carboxylase (ACC), and sterol regulatory element-binding protein 1 (SREBP-1), and also upregulated genes and protein expression of lipid oxidation such as peroxisome proliferator-activated receptor alpha (PPARα) and carnitine palmitoyltransferase 1a (CPT1A). Administration of MJM60958 increased the relative abundance of specific microbial taxa such as Verrucomicrobia, which are abundant in non-NAFLD mice, and reduced Firmicutes, which are a major group in NAFLD mice. MJM60958 affected the modulation of gut microbiota and altered the strain profile of short-chain fatty acids (SCFAs) production in the cecum by reduced lactic acid and enhanced acetic acid production. Overall, MJM60958 showed potential as a probiotic that can prevent and treat NAFLD.

Polybrominated diphenyl ethers in indoor dusts from industrial factories, offices, and houses in northern Vietnam: Contamination characteristics and human exposure.

Information about the occurrence of polybrominated diphenyl ethers (PBDEs) in indoor dusts from various industrial sectors in Southeast Asia is still scarce. In this study, concentrations and congener-specific profiles of PBDEs were determined in indoor dusts from industrial factories, offices, and houses in northern Vietnam. Levels of Σ8PBDEs were higher in the office dusts (median 270; range 230-300 ng/g) and factory dusts (170; 89-510 ng/g) than in the house dusts (61; 25-140 ng/g). BDE-209 was the most dominant congener, accounting for 27-98% (average 62%) of Σ8PBDEs, suggesting the abundance of products treated with deca-BDE mixtures. Residential, commercial, and industrial activities in the studied locations of this survey were not significant sources of PBDEs as compared to those of informal waste processing activities in Vietnam. Relatively low PBDE concentrations detected in our dust samples partially reflect effectiveness of the global PBDE phase-out. Human exposure and health risk associated with dust-bound PBDEs were estimated, indicating acceptable levels of risk (i.e., neurobehavioral effects). The contributions of workplace dusts in total daily intake doses of PBDEs via dust ingestion were more important for local workers in informal recycling areas than factory workers and general population, raising the need of appropriate labor protection measures.

Field- and clinically derived estimates of Wolbachia-mediated blocking of dengue virus transmission potential in Aedes aegypti mosquitoes.

The wMel strain of Wolbachia can reduce the permissiveness of Aedes aegypti mosquitoes to disseminated arboviral infections. Here, we report that wMel-infected Ae. aegypti (Ho Chi Minh City background), when directly blood-fed on 141 viremic dengue patients, have lower dengue virus (DENV) transmission potential and have a longer extrinsic incubation period than their wild-type counterparts. The wMel-infected mosquitoes that are field-reared have even greater relative resistance to DENV infection when fed on patient-derived viremic blood meals. This is explained by an increased susceptibility of field-reared wild-type mosquitoes to infection than laboratory-reared counterparts. Collectively, these field- and clinically relevant findings support the continued careful field-testing of wMel introgression for the biocontrol of Ae. aegypti-born arboviruses.

Mechano-chemical stability and water effect on gas selectivity in mixed-metal zeolitic imidazolate frameworks: a systematic investigation from van der Waals corrected density functional theory.

A series of Zn/Cu Zeolitic Imidazolate Frameworks (ZIFs) ZIF-202, -203, and -204 are systematically investigated by Density Functional Theory (DFT) with and without van der Waals (vdW) corrections. The elastic constants for non-solvent structures indicate that ZIF-202 and -204 are mechanically stable while ZIF-203 is unstable, which arises from the stiffness along the x-axis under a uniaxial strain in the PBE-D3 method. By considering the presence of solvents in ZIF-203, a structural phase transformation from a monoclinic to a triclinic structure is found which could be explained by the Jahn-Teller distortion. From the chemical bonding point of view, it is found that vdW interactions and hybridization between d-orbitals (copper) and p-orbitals (imidazolate) are the main-driving forces in stabilizing ZIF-202 and -204, respectively. The electronic structure calculations predict the presence of two optical transitions in the visible region in agreement with the experimental observation for ZIF-204 both without and with water. The DFT simulations reveal that CO2 molecules prefer to locate near imidazolate and water in dry and hydrated ZIF-204, respectively. The analysis of Canonical Monte Carlo (GCMC) simulations reveals that Coulomb interaction between CO2 and H2O molecules is mainly responsible for the enhanced CO2 uptake and selectivity under humid conditions compared to dry ones.

Positive effect of exogenous brain-derived neurotrophic factor on impaired neurite development and mitochondrial function in dopaminergic neurons derived from dental pulp stem cells from children with attention deficit hyperactivity disorder.

Attention deficit hyperactivity disorder (ADHD) is one of the most common neurodevelopmental disorders and is characterized by impaired attention, hyperactivity, and impulsivity. While multiple etiologies are implicated in ADHD, its underlying mechanism(s) remain unclear. Although previous studies have suggested dysregulation of dopaminergic signals, mitochondria, and brain-derived neurotrophic factor (BDNF) in ADHD, few studies have reported these associations directly. Stem cells from human exfoliated deciduous teeth (SHED) can efficiently differentiate into dopaminergic neurons (DNs) and are thus a useful disease-specific cellular model for the study of neurodevelopmental disorders associated with DN dysfunction. This study aimed to elucidate the relationships between DNs, mitochondria, and BDNF in ADHD by analyzing DNs differentiated from SHED obtained from three boys with ADHD and comparing them to those from three typically developing boys. In the absence of exogenous BDNF in the cell culture media, DNs derived from boys with ADHD (ADHD-DNs) exhibited impaired neurite outgrowth and branching, decreased mitochondrial mass in neurites, and abnormal intracellular ATP levels. In addition, BDNF mRNA was significantly decreased in ADHD-DNs. Supplementation with BDNF, however, significantly improved neurite development and mitochondrial function in ADHD-DNs. These results suggest that ADHD-DNs may have impaired neurite development and mitochondrial function associated with insufficient production of BDNF, which may be improved by exogenous BDNF supplementation. Findings such as these, from patient-derived SHED, may contribute to the future development of treatment strategies for aberrant dopaminergic signaling, mitochondrial functioning, and BDNF levels implicated in ADHD pathogenesis.

Altered development of dopaminergic neurons differentiated from stem cells from human exfoliated deciduous teeth of a patient with Down syndrome.

BACKGROUND: Down syndrome (DS) is a common developmental disorder resulting from the presence of an additional copy of chromosome 21. Abnormalities in dopamine signaling are suggested to be involved in cognitive dysfunction, one of the symptoms of DS, but the pathophysiological mechanism has not been fully elucidated at the cellular level. Stem cells from human exfoliated deciduous teeth (SHED) can be prepared from the dental pulp of primary teeth. Importantly, SHED can be collected noninvasively, have multipotency, and differentiate into dopaminergic neurons (DN). Therefore, we examined dopamine signaling in DS at the cellular level by isolating SHED from a patient with DS, differentiating the cells into DN, and examining development and function of DN. METHODS: Here, SHED were prepared from a normal participant (Ctrl-SHED) and a patient with DS (DS-SHED). Initial experiments were performed to confirm the morphological, chromosomal, and stem cell characteristics of both SHED populations. Next, Ctrl-SHED and DS-SHED were differentiated into DN and morphological analysis of DN was examined by immunostaining. Functional analysis of DN was performed by measuring extracellular dopamine levels under basal and glutamate-stimulated conditions. In addition, expression of molecules involved in dopamine homeostasis was examined by quantitative real-time polymerase chain reaction and immunostaining. Statistical analysis was performed using two-tailed Student's t-tests. RESULTS: Compared with Ctrl-SHED, DS-SHED showed decreased expression of nestin, a neural stem-cell marker. Further, DS-SHED differentiated into DN (DS-DN) exhibiting decreased neurite outgrowth and branching compared with Ctrl-DN. In addition, DS-DN dopamine secretion was lower than Ctrl-DN dopamine secretion. Moreover, aberrant expression of molecules involved in dopaminergic homeostasis was observed in DS-DN. CONCLUSIONS: Our results suggest that there was developmental abnormality and DN malfunction in the DS-SHED donor in this study. In the future, to clarify the detailed mechanism of dopamine-signal abnormality due to DN developmental and functional abnormalities in DS, it is necessary to increase the number of patients for analysis. Non-invasively harvested SHED may be very useful in the analysis of DS pathology.

Comparison of the microdrop and minimum volume cooling methods for vitrification of porcine in vitro-produced zygotes and blastocysts after equilibration in low concentrations of cryoprotectant agents.

We compared the efficacy of the microdrop and minimum volume cooling (MVC) methods for the vitrification of in vitro-produced porcine zygotes and blastocysts after equilibration in low concentrations of cryoprotectant agents. Zygotes and blastocysts were equilibrated in 2% (v/v) ethylene glycol and 2% (v/v) propylene glycol for 13-15 min. Then, they were vitrified in a medium comprised of 17.5% ethylene glycol, 17.5% propylene glycol, 0.3 M sucrose, and 50 mg/ml polyvinylpyrrolidone either by either dropping them directly into liquid nitrogen (microdrop method) or placing them on Cryotop sheets in a minimum volume of medium and plunging into liquid nitrogen (MVC method). Both zygotes and blastocysts were successfully vitrified. For the vitrification of zygotes, the MVC and microdrop methods were equally effective; however, for blastocyst vitrification, MVC was superior. For both methods, the vitrification of zygotes produced higher-quality embryos than the vitrification of blastocysts.

Host and viral features of human dengue cases shape the population of infected and infectious Aedes aegypti mosquitoes.

Dengue is the most prevalent arboviral disease of humans. The host and virus variables associated with dengue virus (DENV) transmission from symptomatic dengue cases (n = 208) to Aedes aegypti mosquitoes during 407 independent exposure events was defined. The 50% mosquito infectious dose for each of DENV-1-4 ranged from 6.29 to 7.52 log10 RNA copies/mL of plasma. Increasing day of illness, declining viremia, and rising antibody titers were independently associated with reduced risk of DENV transmission. High early DENV plasma viremia levels in patients were a marker of the duration of human infectiousness, and blood meals containing high concentrations of DENV were positively associated with the prevalence of infectious mosquitoes 14 d after blood feeding. Ambulatory dengue cases had lower viremia levels compared with hospitalized dengue cases but nonetheless at levels predicted to be infectious to mosquitoes. These data define serotype-specific viremia levels that vaccines or drugs must inhibit to prevent DENV transmission.

Modelling of faecal indicator bacteria (FIB) in the Red River basin (Vietnam).

Many studies have been published on the use of models to assess water quality through faecal contamination levels. However, the vast majority of this work has been conducted in developed countries and similar studies from developing countries in tropical regions are lacking. Here, we used the Seneque/Riverstrahler model to investigate the dynamics and seasonal distribution of total coliforms (TC), an indicator of faecal contamination, in the Red River (Northern Vietnam) and its upstream tributaries. The results of the model showed that, in general, the overall correlations between the simulated and observed values of TC follow a 1:1 relationship at all examined stations. They also showed that TC numbers were affected by both land use in terms of human and livestock populations and by hydrology (river discharge). We also developed a possible scenario based on the predicted changes in future demographics and land use in the Red River system for the 2050 horizon. Interestingly, the results showed only a limited increase of TC numbers compared with the present situation at all stations, especially in the upstream Vu Quang station and in the urban Ha Noi station. This is probably due to the dominance of diffuse sources of contamination relative to point sources. The model is to our knowledge one of the first mechanistic models able to simulate spatial and seasonal variations of microbial contamination (TC numbers) in the whole drainage network of a large regional river basin covering both urban and rural areas of a developing country.

Proteolysis of Sardine (Sardina pilchardus) and Anchovy (Stolephorus commersonii) by Commercial Enzymes inSaline Solutions.

Fish sauce production is a very long process and there is a great interest in shortening it. Among the different strategies to speed up this process, the addition of external proteases could be a solution. This study focuses on the effect of two commercial enzymes (Protamex and Protex 51FP) on the proteolysis of two fish species traditionally converted into fish sauce: sardine and anchovy, by comparison with classical autolysis. Hydrolysis reactions were conducted with fresh fish at a temperature of 30 °C and under different saline conditions (from 0 to 30% NaCl). Hydrolysis degree and liquefaction of the raw material were used to follow the process. As expected, the proteolysis decreased with increasing amount of salt. Regarding the fish species, higher rate of liquefaction and higher hydrolysis degree were obtained with anchovy. Between the two proteases, Protex 51FP gave better results with both fish types. This study demonstrates that the addition of commercial proteases could be helpful for the liquefaction of fish and cleavage of peptide bonds that occur during fish sauce production and thus speed up the production process.