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Peptidoglycan is a major constituent of the bacterial cell wall. Its integrity as a polymeric edifice is critical for bacterial survival and, as such, it is a preeminent target for antibiotics. The peptidoglycan is a dynamic crosslinked polymer that undergoes constant biosynthesis and turnover. The soluble lytic transglycosylase (Slt) of Pseudomonas aeruginosa is a periplasmic enzyme involved in this dynamic turnover. Using amber‐codon‐suppression methodology in live bacteria, we incorporated a fluorescent chromophore into the structure of Slt. Fluorescent microscopy shows that Slt populates the length of the periplasmic space and concentrates at the sites of septation in daughter cells. This concentration persists after separation of the cells. Amber‐codon‐suppression methodology was also used to incorporate a photoaffinity amino acid for the capture of partner proteins. Mass‐spectrometry‐based proteomics identified 12 partners for Slt in vivo. These proteomics experiments were complemented with in vitro pulldown analyses. Twenty additional partners were identified. We cloned the genes and purified to homogeneity 22 identified partners. Biophysical characterization confirmed all as bona fide Slt binders. The identities of the protein partners of Slt span disparate periplasmic protein families, inclusive of several proteins known to be present in the divisome. Notable periplasmic partners (KD < 0.5 μM) include PBPs (PBP1a, KD = 0.07 μM; PBP5 = 0.4 μM); other lytic transglycosylases (SltB2, KD = 0.09 μM; RlpA, KD = 0.4 μM); a type VI secretion system effector (Tse5, KD = 0.3 μM); and a regulatory protease for alginate biosynthesis (AlgO, KD < 0.4 μM). In light of the functional breadth of its interactome, Slt is conceptualized as a hub protein within the periplasm. [ABSTRACT FROM AUTHOR]

The 11 lytic transglycosylases of Pseudomonas aeruginosa have overlapping activities in the turnover of the cell‐wall peptidoglycan. Rare lipoprotein A (RlpA) is distinct among the 11 by its use of only peptidoglycan lacking peptide stems. The spatial localization of RlpA and its interactome within P. aeruginosa are unknown. We employed suppression of introduced amber codons at sites in the rlpA gene for the introduction of the unnatural‐amino‐acids Νζ‐[(2‐azidoethoxy)carbonyl]‐l‐lysine (compound 1) and Nζ‐[[[3‐(3‐methyl‐3H‐diazirin‐3‐yl)propyl]amino]carbonyl]‐l‐lysine (compound 2). In live P. aeruginosa, full‐length RlpA incorporating compound 1 into its sequence was fluorescently tagged using strained‐promoted alkyne‐azide cycloaddition and examined by fluorescence microscopy. RlpA is present at low levels along the sidewall length of the bacterium, and at higher levels at the nascent septa of replicating bacteria. In intact P. aeruginosa, UV photolysis of full‐length RlpA having compound 2 within its sequence generated a transient reactive carbene, which engaged in photoaffinity capture of neighboring proteins. Thirteen proteins were identified. Three of these proteins—PBP1a, PBP5, and MreB—are members of the bacterial divisome. The use of the complementary methodologies of non‐canonical amino‐acid incorporation, photoaffinity proximity analysis, and fluorescent microscopy confirm a dominant septal location for the RlpA enzyme of P. aeruginosa, as a divisome‐associated activity. This accomplishment adds to the emerging recognition of the value of these methodologies for identification of the intracellular localization of bacterial proteins. [ABSTRACT FROM AUTHOR]

The morphology and composition are two key factors to determine the thermoelectric performance of aqueously synthesized tin selenide (SnSe) crystals; however, their controlling is still under exploring. In this study, we report a high figure‐of‐merit (ZT) of ∼1.5 at 823 K in p‐type polycrystalline Sn1 − xSe resulted from a synergy of morphology control and vacancy optimization, realized by carefully tuning the sodium hydroxide (NaOH) concentration during solvothermal synthesis. After a comprehensive investigation on various NaOH concentrations, it was found that an optimized NaOH amount of 10 mL with a concentration of 10 mol L−1 can simultaneously achieve a large average crystal size and a high Sn vacancy concentration of ∼2.5%. The large microplate‐like crystals lead to a considerable anisotropy in the sintered pellets, and the high Sn vacancy level contributes to an optimum hole concentration to the level of ∼2.3 × 1019 cm−3, and in turn a high power factor of ∼7.4 μW cm−1 K−2 at 823 K, measured along the direction perpendicular to the sintering pressure. In addition, a low thermal conductivity of ∼0.41 W m−1 K−1 is achieved by effective phonon scattering at localized crystal imperfections including lattice distortions, grain boundaries, and vacancy domains, as observed by detailed structural characterizations. Furthermore, a competitive compressive strength of ∼52.1 MPa can be achieved along the direction of high thermoelectric performance, indicating a mechanically robust feature. This study provides a new avenue in achieving high thermoelectric performance in SnSe‐based thermoelectric materials. [ABSTRACT FROM AUTHOR]

Background and Aim: Chronic hemodialysis patients are at high risk of contracting hepatitis B (HBV) and C (HCV) virus infections. In Vietnam, the seroprevalence of HBV and HCV infections is approximately 10 and 4%, respectively. Although the chronic hemodialysis population is increasing, relatively little epidemiology is available for HBV and HCV infections in this population. To address this, we reviewed the current literature on the magnitude of these infections in the hemodialysis population in Vietnam. Methods: Four databases were used to search for publications containing the prevalence of HBV and/or HCV infections in hemodialysis patients in Vietnam. Grey literature search was utilized to identify local publications. Prevalence and 95% confidence interval were used or calculated, and a meta‐analysis was conducted on HBV and HCV prevalence for comparison. Results: Sixteen studies were included in the review. The search identified knowledge gaps in the current literature. Available data show that HBV and HCV infections remain prevalent in the hemodialysis population. HBV prevalence is not different between the north and the south of Vietnam. The pattern of HCV prevalence is different, with recent reports of lower prevalence in the south than in the north, while HCV prevalence varies between hemodialysis units in the same regions. Conclusions: A national prevalence survey of hemodialysis patients would improve the reliability and generalizability of the findings. However, the review confirmed that both HBV and HCV were prevalent in hemodialysis patients. The findings support a reinforcement of infection prevention to minimize the risk of HBV and HCV transmission in hemodialysis facilities. [ABSTRACT FROM AUTHOR]

The proportion of elderly people in big cities of developing countries, including Vietnam, is rapidly increasing during the age of rampant urbanization. This is being followed by a sustained rise of illnesses, especially mental health issues. The objective of this study was to analyze the association between depression and the factors associated with depression among the elderly. In a cross-sectional study, 299 elderly living in Hanoi, Vietnam, were approached for data collection. Self-reported depression among the elderly was 66.9% (32.8% mild, 30.4% moderate, and 3.7% severe cases). In multivariate analysis, there were significant associations between age, number of physical activities, number of medicine intake, and 3 domains of quality of life (physical health, psychological health, and environmental health) and depression. Age and the number of medicine intake are positively correlated with depression, accounting for 57.94% and 58.93%, respectively. On the contrary, the number of physical activities and the 3 domains of quality life mentioned above are negatively correlated with depression. In the urban setting of a developing country like Vietnam, the elderly have experienced common depression. Recognizing depression among the elderly—which is individual and social—helps us design public health programs. Screening for early depression, joining social programming, and participating in physical activities may improve the mental life of the elderly. [ABSTRACT FROM AUTHOR]

Abstract: Introduction: Modelling suggests that early diagnosis and immediate antiretroviral therapy (ART) among key populations would have a substantial impact in reducing HIV transmission and mortality in Vietnam. An implementation research project of “test‐and‐treat” among people who inject drugs (PWID) was developed to inform effective roll‐out of such interventions. Methods: “Test‐and‐treat” was offered to PWID in two high burden provinces, Thai Nguyen and Thanh Hoa. The interventions comprised the offer of biannual HIV testing and immediate ART, irrespective of CD4 count. PWID were enrolled between April 2014 and July 2015 and followed up for 12 months, and retention, HIV viral load (VL) and risk behaviours were assessed. Retention in care of this prospective cohort was compared with the retention among men enrolled in care in the preceding period (April 2012 to March 2013) at the same clinics when ART was initiated at CD4 cell count ≤350 cells/mm3. Results: In total, 287 HIV positive PWID started immediate ART. The majority (98%) were men; median age was 34; and median (interquartile range) CD4 count was 199 (50 to 402) cells/mm3. After 12 months, 238 participants (83%) were retained on ART, and 205 achieved viral suppression (<1000 copies/mL) (92% among those in whom VL was measured, 71% overall). Baseline CD4 count ≤100 cells/mm3 and history of imprisonment were associated with lower retention and viral suppression, while engagement in methadone maintenance was associated with higher retention. Retention in care was higher in the “test‐and‐treat” cohort (83%) compared with men enrolled in care in the preceding period (78%), primarily because lost‐to‐follow‐up during pre‐ART care was eliminated. No decline in consistent condom use and clean needle use was observed. Conclusions: Early ART initiation resulted in successful treatment outcomes among PWID, with no observed increase in self‐reported risk behaviours, suggesting feasibility and potential effectiveness of “test‐and‐treat” approach. The results also call for differentiated care for PWID, including promoting early diagnosis and engagement in methadone maintenance therapy while enhancing care for those with advanced HIV disease and history of imprisonment. [ABSTRACT FROM AUTHOR]

The southern yellow-cheeked crested gibbon (Nomascus gabriellae), an endangered species native to Vietnam and Cambodia, lives exclusively in undisturbed tropical forests and depends primarily on ripe fruit for food. Although this species is highly threatened, its ecology and conservation status remain relatively unknown. In order to understand how this heavily frugivorous primate adapts to the seasonal fluctuation of fruit resources in the forest, we collected feeding behavior and ranging activity data on one group of southern yellow-cheeked crested gibbons in Cat Tien National Park, Vietnam, over 1-year period. We compared these data to information on phenological patterns at the site gleaned during a prior study. We found that the gibbons gathered most of their food from 69 different plant species and also consumed insects and bird eggs. Fruits were the main dietary item (43.3%), followed by leaves (38.4%), flowers (11.6%), and other plant parts (6.0%). A significant seasonal shift in diet was observed; fruit generally dominated the diet in the rainy season and leaves in the dry season. The gibbons often started daily activities very early (05:10 am) in the morning and also ended quite early (16:45 pm) in the afternoon. Socializing was concentrated in the early morning, feeding had a bimodal pattern of high activity levels in mid-morning and mid-afternoon, and resting was most intense at the earliest and latest hours of the day and at midday, with proportionally less time used for traveling at these times. Averaged over the annual cycle, the gibbons spent 45% of their time feeding, 31.9% resting, 14.1% traveling, and 9.0% socializing. The percentage of time allocated to different activities varied significantly across months and between the dry and rainy seasons. Monthly variation in the activity budget was strongly related to changes in diet. In the rainy season, when the gibbons ate a higher percentage of fruit, they decreased their feeding time, while increasing traveling time in search of food; conversely, in the dry season, when they fed on a higher percentage of leaves, they decreased traveling time. Overall, our results show that the activity budget and diet of the southern yellow-cheeked crested gibbon are associated with seasonal shifts in climate. This study provides information relevant to the conservation and management of this endangered species by identifying important habitat conditions for reintroducing captive animals into the wild and providing insight into dietary needs, which may be relevant to the maintenance of animals in rescue centers. [ABSTRACT FROM AUTHOR]

Objective In this study, the associations between vitamin D, insulin sensitivity, and inflammation and their relationships with adipose tissue expression of vitamin D receptor (VDR) and inflammatory markers in women with morbid obesity were determined. Methods An oral glucose tolerance test prior to surgery was completed by healthy premenopausal women ( n = 76) seeking bariatric surgery. Abdominal subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT) were collected during surgery. Results Approximately, 70% of our subjects were vitamin D sufficient or optimal, and 80% had normal glucose tolerance. No significant association between serum 25-hydroxyvitamin D [25(OH)D] with circulating inflammatory markers or insulin sensitivity was identified. In subjects with waist circumference of <139 cm ( n = 42), log25(OH)D positively predicted VAT logIL-6 mRNA expression ( P = 0.003). LogVDR expression was positively correlated with the expression of inflammatory markers in both SAT (logIL-1β mRNA: r = 0.95, P < 0.0001; logTNF mRNA: r = 0.82, P < 0.0001) and VAT (logIL-1β mRNA: r = 0.89, P < 0.0001; logTNF mRNA: r = 0.75, P < 0.0001). VAT logVDR expression positively predicted logHOMA-IR in non-African American subjects ( P = 0.05). Conclusions The beneficial effects of vitamin D on inflammation and insulin sensitivity were not supported by our findings. VDR does not appear to possess a protective effect in adipose tissue. [ABSTRACT FROM AUTHOR]

The article discusses the use of consolidative radiotherapy for treatment of bulky Hodgkin lymphoma patients, and also mentions the role of positron emission tomography (PET) scan in treatment planning. It mentions patient received second line chemotherapy followed by autologous stem cell transplant. It also mentions radiotherapy in patients with bulky disease is safe.

This paper proposes a new approach to distribution system named Three-wire Network (3-NET). Considering the integration of different distributed generation (DG) technologies as well as the diversity of loads, the idea of 3-NET is splitting a single power network into three qualitatively different networks: (i) a high quality direct current (DC) network; (ii) a conventional alternating current (AC) network; and (iii) a low quality DC network. By this configuration, the multi-stage conversion of energy from DG sources can be reduced, whereas loads can be supplied with different power quality and reliability levels as desired. In order to evaluate the potential benefits of 3-NET, the operational strategy is formulated in a market model; the reliability performance is investigated using Monte Carlo simulation and quantified in terms of interruption costs. In the case study, the proposed 3-NET is considered for integrating a certain amount of DG into a specific distribution system and then compared with another system approach: hybrid AC-DC microgrid. The simulation shows that although the operation costs can be slightly higher, the 3-NET shows a great improvement in reliability performance in comparison with the hybrid microgrid. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Background and Aim: Incidence and mortality of hepatocellular carcinoma (HCC) has increased markedly over the last three decades in Australia. An increasing proportion of HCC cases is related to chronic viral hepatitis including hepatitis B virus (HBV) infection. However, there is very limited data on HBV-related HCC survival. Methods: Data on HBV-related HCC cases was obtained from a community-based linkage study. HCC cases notified to the New South Wales (NSW) Central Cancer Registry (CCR) during the period 1994–2002 were linked to HBV notifications from the NSW Health Department. Age, sex, country of birth, year of diagnosis, tumor stage were extracted from the CCR database. Survival analysis was conducted to determine median survival and identify predictors of survival. Results: Over the 9-year study period, 278 HCC cases were linked to chronic HBV infection. The majority of cases were male (83.5%) and overseas-born (93.6%); Asian-born cases accounted for 72.1%. Median survival following HCC diagnosis was 15.0 months. HCC survival was poorer among older age groups ( P < 0.0001), and among cases with regional spread (hazard ratio, 3.23; 95% confidence interval, 1.83–5.69; P < 0.0001) and distant metastases (hazard ratio, 3.85; 95% confidence interval, 2.44–6.08; P < 0.0001). Sex, region of birth and study period (1994–1997 vs 1998–2002) were not associated with HCC survival. Conclusion: The vast majority of HBV-related HCC were overseas-born, however, region of birth was unrelated to HCC survival. The continued extremely poor HCC survival, including lack of improvement in HCC survival in more recent years, suggests low uptake of HCC screening programs. Public health strategies including early diagnosis and appropriate referral for antiviral therapy assessment and increased HCC screening among high-risk populations are required to reduce HCC incidence and improve HCC survival. [ABSTRACT FROM AUTHOR]

Aims To provide an overall picture of drug abuse in Vietnam, its prevalence, correlates and patterns. Methods Studies addressing the drug abuse problem in Vietnam are reviewed. Attention is paid to studies conducted from 1993 onwards. The reviewed studies were collected from both refereed and non-refereed sources. Results Drug abuse is rising sharply in Vietnam: almost threefold over the past 10 years. From a predominantly rural-mountainous phenomenon, illicit drug abuse spread rapidly to urban areas. Meanwhile, the average age of drug users has declined and more women have been engaging in drug consumption. At the same time, heroin has replaced opium as the most preferred drug in the country's illicit drug market, especially among young users in urban areas. At the national level, the second main route of drug administration, injecting, has exceeded smoking and taken precedence in the country's drug abuse culture, especially among heroin users. Conclusion Drug abuse in Vietnam has changed radically over the past decade, which has implications for the national and international community and requires further research to fill the knowledge gap and to inform intervention policy for better drug control policy. [ABSTRACT FROM AUTHOR]