Streptococcus suis-Associated Meningitis in a Southern Region of Vietnam.

Streptococcus suis is the most common and severe cause of meningitis in Vietnam, but the recent data about epidemiological characteristics and sequelae are still inadequate. We performed a retrospective study to describe the epidemiology, clinical characteristics, and outcomes of patients with S. suis-associated meningitis. A retrospective study was carried out by searching records from the Hospital for Tropical Diseases, Ho Chi Minh City, Vietnam, between January 2016 and January 2020. All data concerning epidemiological, clinical, and subclinical characteristics and treatment results were collected and analyzed. Over the study period, 153 cases were included in this study, with 95 cases occurring in the 2016-2017 period. The median age of all patients was 52 years (range, 29-90 years), and 70.6% of patients were male. Fifty-two patients (34%) were farmers, and the Mekong Delta was the region with the highest number of cases (60.1%). The most frequent manifestation of infection was fever (151/153, 98.7%), followed by hearing loss (64/153, 41.8%), and one patient (0.7%) died. All isolates remained susceptible to ceftriaxone, penicillin, vancomycin, and levofloxacin, whereas 99.2% of isolates were resistant to tetracycline. Occupational exposure to pigs and the consumption of contaminated food have been identified as primary risk factors associated with this zoonosis, and our study found no significant changes in epidemiological factors compared with past data. The Mekong Delta continues to be the most affected region for S. suis meningitis in southern Vietnam, with S. suis serotype 2 remaining the most relevant agent.

Central Lymphatic Imaging in Adults with Spontaneous Chyluria.

Purpose: Chyluria is a rare condition primarily prevalent in developing countries in tropical regions. In chyluria, there exists the communication between lymphatic vessels and the urinary tract, but the specific mechanism of this communication remains undocumented. The objective of this study was to assess the morphology of the main lymphatic vessels including the uro-lymphatic fistula, the thoracic duct using Magnetic Resonance Lymphangiography (MRL) and Intranodal Lymphangiography (IL). Materials and Methods: A retrospective study spanning five years, from January 2020 to January 2024, included 43 patients diagnosed with chyluria through cystoscopy and quantitative urine testing for triglycerides. These patients underwent MRL and then IL for uro-lymphatic fistula embolization. Results: The study involved 43 patients with an average age of 66.1 ± 19.5 years, with a male-to-female ratio of 1:2. Uro-lymphatic fistula occurred predominantly in the left kidney (72.1%), followed by the right kidney (20.9%), and both sides (7%). MRL imaging showed the thoracic duct in 100% of cases but visualized only 84.5% of the uro-lymphatic fistulas. In contrast, IL imaging showed the thoracic duct in 51.5% of patients but visualized uro-lymphatic fistulas in 100% of cases. In the procedure of IL, the average visualization time of the thoracic duct was 45 minutes, with a range of 35 to 69 minutes. Conclusion: MRL and IL complement each other in diagnosing the main lymphatic vessels in chyluria patients. The observed circulatory stasis in the thoracic duct supports the hypothesis that it contributes to increased pressure in the thoracic duct and the formation uro-lymphatic fistula as collateral circulations.

Differentiation of glioblastoma and primary central nervous system lymphomas using multiparametric diffusion and perfusion magnetic resonance imaging.

The present study aimed to determine whether combining diffusion-weighted (DWI) and dynamic susceptibility contrast-enhanced perfusion-weighted (DSC-PWI) magnetic resonance imaging (MRI) could differentiate between primary central nervous system lymphoma (PCNSL) and glioblastoma (GBM). The present retrospective study evaluated 45 patients with histologically confirmed brain tumors, of which 18 had PCNSLs and 27 had GBMs. All patients underwent conventional, DWI, and DSC-PWI MRIs before the surgical removal of the lesion or stereotactic biopsy. The solid tumor component, peritumoral edema, and abnormal white matter were measured in three regions of interest to evaluate relative cerebral blood volume (rCBV), apparent diffusion coefficient (ADC) and DWI. In conventional MRI, there were significant differences in tumor numbers, tumor enhancement type, tumor necrosis, hemorrhage and open-ring sign between GBM and PCNSL. Solid tumor ADC and rCBV values (ADCt and rCBVt, respectively) and their ratios with abnormal white matter amounts were significantly higher in GBM cases than in PCNSL cases (P<0.05). The rCBV value for peritumoral edema (rCBVe) and its ratio with abnormal white matter amount (rCBVe/n) were significantly higher in GBM cases than in PCNSL cases (P<0.05). However, ADC values did not differ significantly for peritumoral edema. DWI values did not differ significantly. Combining rCBVt and rCBVe/n provided a perfect area under the receiver operating characteristic curve of 1.00, with 100% sensitivity and 100% specificity for distinguishing GBM from PCNSL. In the results of the present study, the major criterion in the decision-making process distinguishing PCNSL from GBM was the combined rCBVt and rCBVe/n parameter. A minor criterion was the ADCt value of the lesion.

Splenic ectopic pregnancy: Rare location of ectopic pregnancy, how does it present?

Splenic ectopic pregnancy (SEP) is a rare high-mortality condition, particularly relating to life-threatening intraperitoneal bleeding due to a high risk of spontaneous rupture. Diagnosing in a timely fashion is extremely crucial and the patients could benefit from active treatment strategies and early management. In this article, we reviewed a case of 40 years-old female who complained of lower quadrant abdominal pain and amenorrhea with a history of intrauterine device (IUD) insertion for over 6 years. Elevating b-human chorionic gonadotropin (HCG) blood levels were documented, raising concern about pregnancy-related emergency conditions. Ultrasound and magnetic resonance imaging results suggested a splenic ectopic pregnancy entity with a high rupture rate. The patient subsequently underwent laparoscopic resection for splenic mass removal. Ectopic pregnancy should cautiously be excluded in all cases of abdominal pain in childbearing-age women.

Attribution of sources to heavy metal accumulation in the anthropogenically impacted Bach Dang River Estuary, Vietnam.

In the present study, concentrations of 10 heavy metals (Ti, Cr, Mn, Fe, Ni, Cu, Zn, As, Cd and Pb) were determined in superficial sediments from 20 sites within the Bach Dang Estuary, Vietnam. An integrated approach including correlation analysis, principal components analysis and positive matrix factorization was successfully applied to identify possible sources of these heavy metals. The results of this study identified four sources of the heavy metals, namely: natural geogenic, mixed anthropogenic, marine transportation and antifouling paint related sources, contributing 34.33 %, 14.80 %, 23.02 % and 27.86 % to the total metal concentrations, respectively. From an environmental impact perspective, these findings could provide a scientific basis for prevention and control of sediment metal pollution. Accordingly, the use of more environmental friendly antifouling paints should be encouraged to minimize metal accumulation in sediments.

A rare case of a primary central nervous system neuroblastoma mimicking a trigeminal schwannoma in an adult.

Neuroblastoma is a malignant extra-cranial tumor that frequently arises in the pediatric population aged <5 years but is rare in adults. Only a few cases of primary central nervous system neuroblastoma (PCN-NB) have been documented, with most occurring in young patients. In this article, we report an adult case with a PCN-NB in the cerebellopontine angle-middle cranial fossa region that mimicked another neoplasm. We also discuss the magnetic resonance imaging features and pathological characteristics of PCN-NB and differential diagnosis strategies.

The relationship between effective personality and occupational health of lecturers: An empirical assessment in vietnam.

There are gaps in research on the relationship between effective personality and occupational health of lecturers that need to be addressed. This study, therefore, explores the relationship between effective personality and occupational health of lecturers of provincial/city political schools in Vietnam. The survey is carried out in a convenient sampling method with 365 lecturers of provincial/city political schools in Vietnam. The questionnaires are provided to the participants of professional training courses at the Ho Chi Minh National Academy of Politics. The lecturers are willing to fill in the questionnaires at the same time. Descriptive, correlative, and linear regressive analyses are applied. The findings show that all elements of the effective personality structure have positive significant statistical impacts on enhancing self-efficacy, satisfaction, and cognitive affections while negatively causing exhaustion, musculoskeletal disorders, and voice disturbance of the lecturers' occupational health. Recommendations for promoting the effective personality of lecturers are provided. However, the study results are limited to the survey participants, who are lecturers of provincial political schools. Future research could expand the survey participants as well as elements of the effective personality structure and occupational health.

An insight into source apportionment of metals in superficial sediments from the Tien Hai nature reserve of the Red River delta, Vietnam.

In the present study, concentrations of 23 metallic elements (Al, Fe, K, Mg, Ti, Mn, V, Cr, Co, Ni, Cu, Zn, Ga, As, Sr, Zr, Mo, Cd, Ba, W, Hg, Pb and U) were determined in superficial sediments from 20 sites within the Tien Hai nature reserve of the Red River delta. An integrated approach including correlation analysis (CA), principal components analysis (PCA) and positive matrix factorization (PMF) was combined to identify and quantify the sources of these metals. The results indicated that the correlation analysis was able to identify both allochthonous and authigenous origin of metals while the remaining methods were unable to identify these origins. With the help of CA, the PMF model performed better at the source identification of metals than the PCA. The results of PMF demonstrated that weathering products formed on different parent rocks were the biggest contributor to natural sources of metals in the superficial sediments, while agricultural activities were regarded as the major contributor to anthropogenic sources of metals. These findings could provide a scientific basis for environmental protection authority to prevent and control the sediment metal pollution. Accordingly, application of organic amendments and reduction of inorganic fertilizer should be encouraged to minimize metal accumulation in sediments.

Improving the efficiency of n-Si/PEDOT:PSS hybrid solar cells by incorporating AuNP-decorated graphene oxide as a nanoadditive for conductive polymers.

A gold nanoparticle-decorated graphene oxide (GO-AuNP) hybrid material was prepared by using the chemical reduction method. The obtained results showed that the AuNPs of about of 15 nm are well bound on the surface of GO. The GO-AuNP hybrid material was used for transparent conductive film (TCF) and organic/inorganic hybrid solar cells. The TCF based on poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) containing GO-AuNPs was fabricated at room temperature. The obtained results show that the TCF containing 0.5 wt% GO-AuNPs has a high transmittance of 69.7% at 550 nm, a low sheet resistance of 50.5 Ω â–¡-1 and a conductivity that increased to 3960 S cm-1, which is three times higher than those of the PEDOT:PSS and PEDOT:PSS/GO film. The power conversion efficiency (PCE) of the n-Si/PEDOT:PSS hybrid solar cell containing GO-AuNPs was 8.39% and is higher than pristine PEDOT:PSS (5.81%) and PEDOT:PSS/GO (7.58%). This is a result of the increased electrical conductivity and localized surface plasmon resonance of the PEDOT:PSS coating layer containing the GO-AuNP hybrid material.

Enhanced power conversion efficiency of an n-Si/PEDOT:PSS hybrid solar cell using nanostructured silicon and gold nanoparticles.

Herein, the effect of nanostructured silicon and gold nanoparticles (AuNPs) on the power conversion efficiency (PCE) of an n-type silicon/poly(3,4-ethylene dioxythiophene):poly(styrene sulfonate) (n-Si/PEDOT:PSS) hybrid solar cell was investigated. The Si surface modified with different nanostructures including Si nanopyramids (SiNPs), Si nanoholes (SiNHs) and Si nanowires (SiNWs) was utilized to improve light trapping and photo-carrier collection. The highest power conversion efficiency (PCE) of 8.15% was obtained with the hybrid solar cell employing SiNWs, which is about 8%, 20% and 40% higher compared to the devices using SiNHs, SiNPs and planar Si, respectively. The enhancement is attributed to the low reflectance of the SiNW structures and large PEDOT:PSS/Si interfacial area. In addition, the influence of AuNPs on the hybrid solar cell's performance was examined. The PCE of the SiNW/PEDOT:PSS hybrid solar cell with 0.5 wt% AuNP is 8.89%, which is ca. 9% higher than that of the device without AuNPs (8.15%). This is attributed to the increase in the electrical conductivity and localized surface plasmon resonance of the AuNP-incorporated PEDOT:PSS coating layer.

Normal values for high-resolution anorectal manometry in healthy young adults: evidence from Vietnam.

BACKGROUND: High-resolution anorectal manometry (HRAM) has been developed to improve measurement of anorectal functions. This study aims to identify normal HRAM values in healthy young Vietnamese adults. METHODS: We conducted a cross-sectional study at the National Hospital of Traditional Medicine (Hanoi, Vietnam) from July through December 2014. Healthy young adults were invited to participate in the study. All anorectal measurement values were performed using the ISOLAB high-resolution manometry system. Differences between groups were analyzed using Student's t-tests. RESULTS: Thirty healthy young adults, including 15 males and 15 females aged 19-26 years, were recruited. Mean functional anal canal length was 3.4 ± 0.5 cm (range: 2.4-4.8 mm). Mean maximum resting pressure, mean maximum squeezing pressure, mean maximum coughing pressure, and mean maximum strain pressure were 65.5, 168.0, 125.9, and 84.2 mm Hg, respectively. All anal pressure values were significantly different between males and females. For rectal sensation measurements, only the volume at first sensation was significantly higher in males than in females. CONCLUSIONS: This study provides normal HRAM value for healthy young adults in Vietnam. Sex may influence anal pressure and first rectal sensation values in this cohort. Further studies should be conducted in order to improve the quality of HRAM normal values and to confirm the effects of sex.

Solar-Powered Whole-Cell P450 Catalytic Platform for C-Hydroxylation Reactions.

Invited for this month's cover is the joint research group of Prof. Chan Beum Park at the Korea Advanced Institute of Science and Technology (KAIST) and Prof. Chul-Ho Yun at the Chonnam National University (CNU). The image shows how the use of a natural photosensitizer, flavin mononucleotide, and visible light can lead to a cost-effective, green, and sustainable process for P450-catalyzed reactions in a whole-cell system. The Communication itself is available at 10.1002/cssc.202100944.

Solar-Powered Whole-Cell P450 Catalytic Platform for C-Hydroxylation Reactions.

Photobiocatalysis is a green platform for driving redox enzymatic reactions using solar energy, not needing high-cost cofactors and redox partners. Here, a visible light-driven whole-cell platform for human cytochrome P450 (CYP) photobiocatalysis was developed using natural flavins as a photosensitizer. Photoexcited flavins mediate NADPH/reductase-free, light-driven biocatalysis by human CYP2E1 both in vitro and in the whole-cell systems. In vitro tests demonstrated that the photobiocatalytic activity of CYP2E1 is dependent on the substrate type, the presence of catalase, and the acid type used as a sacificial electron donor. A protective effect of catalase was found against the inactivation of CYP2E1 heme by H2 O2 and the direct transfer of photo-induced electrons to the heme iron not by peroxide shunt. Furthermore, the P450 photobiocatalysis in whole cells containing human CYPs 1A1, 1A2, 1B1, and 3A4 demonstrated the general applicability of the solar-powered, flavin-mediated P450 photobiocatalytic system.

Electrochemical Sensor Based on Reduced Graphene Oxide/Double-Walled Carbon Nanotubes/Octahedral Fe3O4/Chitosan Composite for Glyphosate Detection.

In this work, reduced graphene oxide/double-walled carbon nanotubes/octahedral-Fe3O4/chitosan composite material modified screen-printed gold electrodes (rGO/DWCNTs/Oct-Fe3O4/Cs/SPAuE) under inhibition of urease enzyme was developed for the determination of glyphosate (GLY). The electrochemical behaviors of GLY on these electrodes were evaluated by square wave voltammetry (SWV). With the electroactive surface area is 1.7 times higher than that of bare SPAuE, the rGO/DWCNTs/Oct-Fe3O4/Cs/SPAuE for detection of GLY shows a low detection limit (LOD) of ~ 0.08 ppb in a large concentration range of 0.1-1000 ppb. Moreover, it is also successfully applied to the determination of GLY in river water samples with recoveries and relative standard deviations (RSDs) from 98.7% to 106.9% and from 0.79% to 0.87%, respectively. The developed composite will probably provide an universal electrochemical sensing platform that is very promising for environmental monitoring.

Normal Values and Associated Factors in Highresolution Anorectal Manometry in Healthy Vietnamese Adults / Valores normais e fatores associados na manometria anorretal de alta resolução em adultos vietnamitas saudáveis

Abstract Introduction The present study aims to identify normal high-resolution anorectal manometry (HRAM) values and related factors in healthy Vietnamese adults. Methods The present cross-sectional study was conducted at the Viet Duc hospital, Hanoi, Vietnam, during April and May 2019. Healthy volunteers were recruited to participate in the study. Anorectal measurement values from the digestive tract, including pressure, were recorded. Results A total of 76 healthy volunteers were recruited. The mean functional anal canal length was 4.2 ± 0.5 cm, while the mean anal high-pressure zone length was 3.4 ± 0.5 cm. Themean defecation index was 1.4 ± 0.8, with values ranging from 0.3 to 5.0. The mean threshold volume to elicit the rectoanal inhibitory reflex (RAIR) was 18.1 mL. The mean rectal sensation values were 32.4mL, 81.6mL, and 159 mL for first sensation, desire to defecate, and urge to defecate, respectively. Dyssynergic patterns occurred in ~ 50% of the study participants and included mainly types I (27.6%) and III (14.6%). There were significant differences between male and female patients in terms of maximum anal squeeze pressure, maximum anal cough pressure, maximum anal strain pressure, maximum rectal cough pressure, and maximum rectal strain pressure (all p<0.01). Conclusions The present study establishes normal HRAM values in healthy Vietnamese adults, particularly regarding normal values of anorectal pressure and rectal sensation. Further studies that include larger sample sizes should be conducted to further confirm the constants and their relationships.

Resumo Introdução O presente estudo tem como objetivo identificar valores normais de manometria anorretal de alta resolução e fatores relacionados em adultos vietnamitas saudáveis. Métodos O presente estudo transversal foi conduzido no hospital Viet Duc, Hanói, Vietnã, durante abril e maio de 2019. Voluntários saudáveis foram recrutados para participar do estudo. Valores de medição anorretal, incluindo pressão do trato digestivo, foram registrados. Resultados Um total de 76 voluntários saudáveis foram recrutados. O comprimento funcional médio do canal anal foi de 4,2 ± 0,5 cm, enquanto o comprimento médio da zona anal de alta pressão foi de 3,4 ± 0,5 cm. O índice médio de defecação foi de 1,4 ± 0,8, com valores variando de 0,3 a 5,0. O volume limite médio para eliciar o reflexo inibitório retoanal (RAIR, sigla em inglês) foi de 18,1 mL. Os valores médios da sensação retal foram 32,4mL, 81,6mL e 159 mL para a primeira sensação, o desejo de defecar e a urgência de defecar, respectivamente. Os padrões dissinérgicos ocorreram em aproximadamente 50% dos participantes do estudo e incluíram principalmente os tipos I (27,6%) e III (14,6%). Houve diferenças significativas entre homens e mulheres na pressão de compressão anal máxima, pressão de tosse anal máxima, pressão de distensão anal máxima, pressão de tosse retal máxima e pressão de distensão retal máxima (todos p<0,01). Conclusões O presente estudo estabelece valores normais de HRAM em adultos vietnamitas saudáveis, particularmente no que diz respeito aos valores normais de pressão anorretal e sensação retal. Mais estudos que incluam tamanhos de amostra maiores devemser realizados a fim de confirmar melhor as constantes e suas relações.

The Application of Sample Pooling for Mass Screening of SARS-CoV-2 in an Outbreak of COVID-19 in Vietnam.

We sampled nasal-pharyngeal throat swabs from 96,123 asymptomatic individuals at risk of SARS-CoV-2 infection, and generated 22,290 pools at collection, each containing samples from two to seven individuals. We detected SARS-CoV-2 in 24 pools, and confirmed the infection in 32 individuals after resampling and testing of 104 samples from positive pools. We completed the testing within 14 days. We would have required 64 days to complete the screening for the same number of individuals if we had based our testing strategy on individual testing. There was no difference in cycle threshold (Ct) values of pooled and individual samples. Thus, compared with individual sample testing, our approach did not compromise PCR sensitivity, but saved 77% of the resources. The present strategy might be applicable in settings, where there are shortages of reagents and the disease prevalence is low, but the demand for testing is high.

Solar Cell Based on Hybrid Structural SiNW/Poly(3,4 ethylenedioxythiophene): Poly(styrenesulfonate)/Graphene.

Solar energy is considered as a potential alternative energy source. The solar cell is classified into three main types: i) solar cells based on bulk silicon materials (monocrystalline, polycrystalline), ii) thin-film solar cells (CIGS, CdTe, DSSC, etc.), and iii) solar cells based on nanostructures and nanomaterials. Nowadays, commercial solar cells are usually made by bulk silicon material, which requires not only high fabrication costs but also limited performance. In this study, the fabrication of high-performance solar cells based on hybrid structure of silicon nanowires/poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate)/graphene (SiNW/PEDOT:PSS/Gr) is focused upon. SiNWs with different lengths of 125, 400, 800 nm, and 2 µm are fabricated by a metal-assisted chemical etching method, and their influence on the performance of the hybrid solar cells is studied and investigated. The experimental results indicate that the suitable SiNW length for the fabrication of the hybrid solar cells is about 400 nm and the best power conversion efficiency obtained is about 9.05%, which is about 2.1 times higher than that of the planar Si solar cell.

GAMMA SPECTRUM STABILIZATION FOR ENVIRONMENTAL RADIATION MONITORING STATIONS USING NAI(TL) DETECTOR.

Gamma spectrum measured by an NaI(Tl) detector is known to be unstable with the in situ temperature. In the present work, an advanced method has been applied to stabilize the gamma spectrum measured by the NaI(Tl) detector at environmental radiation monitoring (ERM) stations. The method is based on experimental data obtained under controlled conditions in laboratory. In the temperature range from 4 to 45°C, the relative deviation of the peak positions within the stabilized gamma spectrum is less than 2%. To test this method in a real scenario, it has been integrated into the ERM station at the Military Institute of Chemical and Environmental Engineering in Hanoi, Vietnam. The results show that the proposed method is ready for a real application.

Comparison of Doppler-Guided Transanal Hemorrhoidal Dearterialization for Grade III and IV Hemorrhoids in Vietnam.

INTRODUCTION: This study aimed to assess the short- and long-term outcomes of Doppler-guided transanal hemorrhoidal dearterialization (THD) for grade III and IV hemorrhoidal disease in Vietnam. METHODS: In a prospective observational design, patients treated for grade III and IV hemorrhoidal disease with the THD method at the National Hospital of Traditional Medicine (Hanoi, Vietnam) were included between June 2012 and December 2013. Patients were evaluated postoperatively at the time they were discharged from the hospital (short-term outcome) and 6 months after surgery (long-term outcome). RESULTS: A total of 128 patients were enrolled in the study, 94 were classified with grade III disease and 34 with grade IV. Grade IV hemorrhoidal patients reported on average 18.2 years of disease symptom duration, while grade III hemorrhoidal patients reported 11.2 years. All patients with grade III and grade IV hemorrhoidal disease had good outcomes at discharge day and reported to return to work in a median of 6 days after THD. At long-term follow-up, the results were good for 80.9% of patients from grade III hemorrhoidal disease and 61.8% of patients from grade IV hemorrhoidal disease. Patient satisfaction with the procedure and outcomes was 93.6% for grade III and 85.3% for grade IV hemorrhoidal patients. CONCLUSIONS: The THD technique was shown to be safe for both grade III and IV hemorrhoidal patients. The THD technique showed better results with grade III hemorrhoidal patients as compared to grade IV hemorrhoidal patients.