Molecular Epidemiology of Escherichia coli Resistant to Carbapenems, Fluoroquinolones, and Aminoglycosides Isolated from One of the Largest Hospitals in Vietnam in 2014-2019.

Introduction: Multidrug-resistant (MDR) Gram-negative bacilli including carbapenem-resistant Gram-negative Enterobacteriaceae (CRE) threaten global health. Little is known, however, about the distribution of antimicrobial resistance genes in MDR isolated from patients in Vietnamese hospitals. In this study, we collected MDR Escherichia coli, defined as E. coli resistance against all fluoroquinolones, aminoglycosides, and carbapenems. Aim: This study was designed to clarify the molecular epidemiology of Escherichia coli isolates resistant to carbapenems, fluoroquinolones, and aminoglycosides isolated from patients admitted to one of the largest hospitals in Vietnam in 2014-2019 based on both whole-genome sequencing (WGS) and phenotypic data. Methodology. Sixty-seven Vietnamese isolates screened by drug resistance by the disk test were subjected to WGS, and their sequences were analyzed to determine their multilocus sequence type (MLST), O-types, H-types, distribution of drug resistance genes, plasmid types, pathogenicity islands (PIs), virulence factor distribution, and phylogenetic evolution using the WGS data. Results: Among the STs detected, ST410 was relatively dominant. Dominant O-types and H-types were O102 and H9 and showed some links, such as those between O102 and H8. The most dominant plasmid type and carbapenemase type were 4 and NDM-5, respectively. MLST, O-types, H-types, plasmid types, and types of carbapenemases were very heterogeneous among the isolates, with no clear correlation between them. Dominant plasmid type carrying drug resistance gene was IncQ1_1. The percentage of isolates positive for drug resistance genes, such as anti-beta-lactams and aminoglycosides, was relatively high because the isolates screened were resistant to carbapenems, fluoroquinolones, and aminoglycosides. Conclusions: MDR E. coli isolates isolated at a high-volume Vietnamese hospital were very heterogeneous, suggesting that they were acquired from different sources, including nosocomial infection, animals, and water. Eradication of MDR E. coli from hospitals and other clinical environments is very challenging because a single measure may be ineffective.

Microorganisms for Ginsenosides Biosynthesis: Recent Progress, Challenges, and Perspectives.

Ginsenosides are major bioactive compounds present in the Panax species. Ginsenosides exhibit various pharmaceutical properties, including anticancer, anti-inflammatory, antimetastatic, hypertension, and neurodegenerative disorder activities. Although several commercial products have been presented on the market, most of the current chemical processes have an unfriendly environment and a high cost of downstream processing. Compared to plant extraction, microbial production exhibits high efficiency, high selectivity, and saves time for the manufacturing of industrial products. To reach the full potential of the pharmaceutical resource of ginsenoside, a suitable microorganism has been developed as a novel approach. In this review, cell biological mechanisms in anticancer activities and the present state of research on the production of ginsenosides are summarized. Microbial hosts, including native endophytes and engineered microbes, have been used as novel and promising approaches. Furthermore, the present challenges and perspectives of using microbial hosts to produce ginsenosides have been discussed.

Four new N-phenethylbenzamide derivatives from the stems of piper betle and their antimicrobial activity.

Four new N-phenethylbenzamide derivatives, named piperbetamides A-D (1-4), and six allylbenzene derivatives (5-10) were isolated from the stems of Piper betle L. Their structures were determined by HR-ESI-MS and NMR spectroscopic methods. Compounds 1-10 were evaluated for their inhibitory effects on the growth of nine microorganisms including five Gram-negative (Escherichia coli, Salmonella enterica serovar Typhimurium, Shigella flexneri, Pseudomonas aeruginosa, and Extended-spectrum beta-lactam resistant Klebsiella pneumoniae), three Gram-positive (Listeria monocytogenes, Methicilin-resistant Staphylococcus aureus, Vancomycin-resistant Enterococcus faecalis), and one yeast (Candida albicans) strains. Compounds 1, 3, 4, 6 and 10 exhibited potential antimicrobial activity against S. flexneri, L. monocytogenes, methicillin-resistant S. aureus and vancomycin-resistant E. faecalis with minimum inhibitory concentration (MIC) values in the range of 16-32 µg/mL.

A modified Sequential Organ Failure Assessment score for dengue: development, evaluation and proposal for use in clinical trials.

BACKGROUND: Dengue is a neglected tropical disease, for which no therapeutic agents have shown clinical efficacy to date. Clinical trials have used strikingly variable clinical endpoints, which hampers reproducibility and comparability of findings. We investigated a delta modified Sequential Organ Failure Assessment (delta mSOFA) score as a uniform composite clinical endpoint for use in clinical trials investigating therapeutics for moderate and severe dengue. METHODS: We developed a modified SOFA score for dengue, measured and evaluated its performance at baseline and 48 h after enrolment in a prospective observational cohort of 124 adults admitted to a tertiary referral hospital in Vietnam with dengue shock. The modified SOFA score included pulse pressure in the cardiovascular component. Binary logistic regression, cox proportional hazard and linear regression models were used to estimate association between mSOFA, delta mSOFA and clinical outcomes. RESULTS: The analysis included 124 adults with dengue shock. 29 (23.4%) patients required ICU admission for organ support or due to persistent haemodynamic instability: 9/124 (7.3%) required mechanical ventilation, 8/124 (6.5%) required vasopressors, 6/124 (4.8%) required haemofiltration and 5/124 (4.0%) patients died. In univariate analyses, higher baseline and delta (48 h) mSOFA score for dengue were associated with admission to ICU, requirement for organ support and mortality, duration of ICU and hospital admission and IV fluid use. CONCLUSIONS: The baseline and delta mSOFA scores for dengue performed well to discriminate patients with dengue shock by clinical outcomes, including duration of ICU and hospital admission, requirement for organ support and death. We plan to use delta mSOFA as the primary endpoint in an upcoming host-directed therapeutic trial and investigate the performance of this score in other phenotypes of severe dengue in adults and children.

Simultaneous determination of vitamin B6 and magnesium using capillary electrophoresis coupled with contactless conductivity detection: Method development, validation, and application to pharmaceutical and nutraceutical samples.

Vitamins and minerals are usually incorporated in pharmaceutical and nutraceutical products, but a simple, rapid, and inexpensive analytical method for their simultaneous determination is still lacking. In this study, we developed a quantification method for pyridoxine (vitamin B6) and magnesium (Mg) by using purpose-made capillary electrophoresis with capacitively coupled contactless conductivity detection (CE-C4D) instrument. Main analytical conditions include: fused silica capillary (total length 55 cm, effective length 40 cm, inner diameter 50 µm); background electrolyte consisted of 10 mM L-arginine/acetic acid (pH 5) with 20% acetonitrile; separation voltage + 20 kV; hydrodynamic injection (siphoning at 20 cm in 25 s). Detection limits of vitamin B6 and Mg were 1 and 0.1 mg/L, respectively. Good linearity (R2 > 0.999) was observed for vitamin B6 and Mg calibration curves over concentration ranges of 3-100 and 0.3-200 mg/L, respectively. The method was applied to analyze vitamin B6 and Mg in several pharmaceutical and nutraceutical samples. The analytical results obtained by our method were in good agreement with reference methods (i.e., HPLC for vitamin B6 and ICP-OES for Mg). High-efficient and low-cost CE-C4D method can accordingly serve as a promising tool for concurrent analysis of inorganic and organic species in pharmaceutical and nutraceutical analysis.

Evaluation of the Safety Profile of the ASFV Vaccine Candidate ASFV-G-ΔI177L.

African swine fever (ASF) is the cause of a recent pandemic that is posing a threat to much of the world swine production. The etiological agent, ASF virus (ASFV), infects domestic and wild swine, producing a variety of clinical presentations depending on the virus strain and the genetic background of the pigs infected. No commercial vaccine is currently available, although recombinant live attenuated vaccine candidates have been shown to be efficacious. In addition to determining efficacy, it is paramount to evaluate the safety profile of a live attenuated vaccine. The presence of residual virulence and the possibility of reversion to virulence are two of the concerns that must be evaluated in the development of live attenuated vaccines. Here we evaluate the safety profile of an efficacious live attenuated vaccine candidate, ASFV-G-ΔI177L. Results from safety studies showed that ASFV-G-ΔI177L remains genetically stable and phenotypically attenuated during a five-passage reversion to virulence study in domestic swine. In addition, large-scale experiments to detect virus shedding and transmission confirmed that even under varying conditions, ASFV-G-ΔI177L is a safe live attenuated vaccine.

Imaging of cryptococcus neoformans infection in breasts: A case report.

There have been few reports on the imaging characteristics of cryptococcus neoformans (C. neoformans) infection of the breast. Herein, we reported the imaging features of C. neoformans infection of the breast in a 41-year-old woman with immune thrombocytopenic purpura. Bilateral, diffuse, hyperechoic, and well-defined margin lesions were observed on breast ultrasounds. In addition, a global asymmetry in the left breast, and a focal asymmetry in the right breast were observed on mammograms. Breast fine needle aspiration and biopsy results revealed a C. neoformans infection. After 5 months of treatment with oral fluconazole and amphotericin B, the lesion on the right breast disappeared on repeated-breast ultrasounds.

Toxicity and Anti-Proliferative Properties of Anisomeles indica Ethanol Extract on Cervical Cancer HeLa Cells and Zebrafish Embryos.

In this study, we showed that crude extract of Anisomeles indica (AI-EtE) expressed its toxicity to HeLa cells with an IC50 dose of 38.8 µg/mL and to zebrafish embryos with malformations, lethality and hatching inhibition at 72-hpf at doses higher than 75 µg/mL. More interestingly, flow cytometry revealed that AI-EtE significantly promoted the number of cells entering apoptotic. Accordingly, the transcript levels of BAX, CASPASE-8, and CASPASE-3 in the cells treated with AI-EtE at IC50 dose were 1.55-, 1.62-, and 2.45-fold higher than those in the control cells, respectively. Moreover, treatment with AI-EtE caused cell cycle arrest at the G1 phase in a p53-independent manner. Particularly, percentages of AI-EtE-treated cells in G1, S, G2/M were, respectively 85%, 6.7% and 6.4%; while percentages of control cells in G1, S, G2/M were 64%, 15% and 19%, respectively. Consistent with cell cycle arrest, the expressions of CDKN1A and CDNK2A in AI-EtE-treated cells were up-regulated 1.9- and 1.64-fold, respectively. Significantly, treatment with AI-EtE also decreased anchorage-independent growth of HeLa cells. In conclusion, we suggest that Anisomeles indica can be considered as a medicinal plant with a possible use against cervical cancer cells; however, the used dose should be carefully monitored, especially when applying to pregnant women.

Epidemiology of Enterobacter cloacae strains producing a carbapenemase or metallo-beta-lactamase in Vietnamese clinical settings in 2014-2017.

Introduction. Little is known about the epidemiology of Enterobacter cloacae strains producing a carbapenemase or metallo-beta-lactamase in Vietnamese hospitals.Aim. This study analysed E. cloacae strains resistant to imipenem or meropenem that had been isolated from patients admitted to one of the largest hospitals in Vietnam in 2014-2017.Methodology. Eighteen Vietnamese (VN) strains were subjected to whole-genome sequencing and their sequences compared with those of 17 E. cloacae strains carrying a carbapenemase or metallo-beta-lactamase in the database (db strains).Results. Although the distribution of virulence factors did not differ significantly between VN and db strains, all 18 VN isolates harboured blaNDM-1, phylogenetic analysis revealed a high clonality of the VN strains. Bayesian phylogenetic analysis suggested that the VN strains speciated relatively recently.Conclusions. Several prevalent clones of carbapenem-resistant E. cloacae have circulated within Vietnamese hospitals. Adequate measures are needed to prevent their further spread.

Wedelolactone from Vietnamese Eclipta prostrata (L) L. Protected Zymosan-induced shock in Mice.

Wedelolactone is known to have biological activities such as anti-inflammation hepatitis, anti-hepatotoxic activity, and trypsin inhibitory effect. However, up to date, there has not been any deep study on the role of wedelolactone for zymosan-induced signaling pathways in the process of regulating the excessive inflammatory responses in host. Here, we demonstrated that wedelolactone plays an essential role for regulation of zymosan-induced inflammatory responses in murine bone marrow-derived macrophages (BMDMs). The zymosan-mediated secretion of tumor necrosis factor-α (TNF)-α), interleukin (IL)-6), and IL12p40 but not IL-10 in BMDMs was significantly inhibited by pre-treatment with wedelolactone (30 µg/mL, P < 0.001). Furthermore, zymosan-induced supreoxide generation, NADPH oxidase (P < 0.001), phosphorylation of p47phox in BMDMs were significantly reduced by pre-treatment of wedelolactone (30 µg/mL). Collectively, these data indicated that wedelolactone reduced zymosan-induced inflammatory responses. Moreover, in-vivo wedelolactone (30 mg/kg) was significantly rescued from zymosan-induced shock through inhibition of systemic inflammatory cytokine levels.

Molecular analysis of pyrazinamide resistance in Mycobacterium tuberculosis in Vietnam highlights the high rate of pyrazinamide resistance-associated mutations in clinical isolates.

Pyrazinamide (PZA) is a key antibiotic in current anti-tuberculosis regimens. Although the WHO has stressed the urgent need to obtain data on PZA resistance, in high tuberculosis burden countries, little is known about the level of PZA resistance, the genetic basis of such resistance or its link with Mycobacterium tuberculosis families. In this context, this study assessed PZA resistance through the molecular analysis of 260 Vietnamese M. tuberculosis isolates. First-line drug susceptibility testing, pncA gene sequencing, spoligotyping and mycobacterial interspersed repetitive units-variable number of tandem repeats (MIRU-VNTR) typing were performed. Overall, the pncA mutation frequency was 38.1% (99 out of 260 isolates) but was higher than 72% (89 out of 123 isolates) in multidrug and quadruple-drug resistant isolates. Many different pncA mutations (71 types) were detected, of which 55 have been previously described and 50 were linked to PZA resistance. Among the 16 novel mutations, 14 are likely to be linked to PZA resistance because of their mutation types or codon positions. Genotype analysis revealed that PZA resistance can emerge in any M. tuberculosis cluster or family, although the mutation frequency was the highest in Beijing family isolates (47.7%, 62 out of 130 isolates). These data highlight the high rate of PZA resistance-associated mutations in M. tuberculosis clinical isolates in Vietnam and bring into question the use of PZA for current and future treatment regimens of multidrug-resistant tuberculosis without PZA resistance testing.

NecroX-5 exerts anti-inflammatory and anti-fibrotic effects via modulation of the TNFα/Dcn/TGFß1/Smad2 pathway in hypoxia/reoxygenation-treated rat hearts.

Inflammatory and fibrotic responses are accelerated during the reperfusion period, and excessive fibrosis and inflammation contribute to cardiac malfunction. NecroX compounds have been shown to protect the liver and heart from ischemia-reperfusion injury. The aim of this study was to further define the role and mechanism of action of NecroX-5 in regulating infl ammation and fi brosis responses in a model of hypoxia/reoxygenation (HR). We utilized HR-treated rat hearts and lipopolysaccharide (LPS)-treated H9C2 culture cells in the presence or absence of NecroX-5 (10 µmol/L) treatment as experimental models. Addition of NecroX-5 signifi cantly increased decorin (Dcn) expression levels in HR-treated hearts. In contrast, expression of transforming growth factor beta 1 (TGFß1) and Smad2 phosphorylation (pSmad2) was strongly attenuated in NecroX-5-treated hearts. In addition, signifi cantly increased production of tumor necrosis factor alpha (TNFα), TGFß1, and pSmad2, and markedly decreased Dcn expression levels, were observed in LPS-stimulated H9C2 cells. Interestingly, NecroX-5 supplementation effectively attenuated the increased expression levels of TNFα, TGFß1, and pSmad2, as well as the decreased expression of Dcn. Thus, our data demonstrate potential antiinflammatory and anti-fibrotic effects of NecroX-5 against cardiac HR injuries via modulation of the TNFα/Dcn/TGFß1/Smad2 pathway.

NecroX-5 protects mitochondrial oxidative phosphorylation capacity and preserves PGC1α expression levels during hypoxia/reoxygenation injury.

Although the antioxidant and cardioprotective effects of NecroX-5 on various in vitro and in vivo models have been demonstrated, the action of this compound on the mitochondrial oxidative phosphorylation system remains unclear. Here we verify the role of NecroX-5 in protecting mitochondrial oxidative phosphorylation capacity during hypoxia-reoxygenation (HR). Necrox-5 treatment (10 µM) and non-treatment were employed on isolated rat hearts during hypoxia/reoxygenation treatment using an ex vivo Langendorff system. Proteomic analysis was performed using liquid chromatography-mass spectrometry (LC-MS) and non-labeling peptide count protein quantification. Real-time PCR, western blot, citrate synthases and mitochondrial complex activity assays were then performed to assess heart function. Treatment with NecroX-5 during hypoxia significantly preserved electron transport chain proteins involved in oxidative phosphorylation and metabolic functions. NecroX-5 also improved mitochondrial complex I, II, and V function. Additionally, markedly higher peroxisome proliferator-activated receptor-gamma coactivator-1α (PGC1α) expression levels were observed in NecroX-5-treated rat hearts. These novel results provide convincing evidence for the role of NecroX-5 in protecting mitochondrial oxidative phosphorylation capacity and in preserving PGC1α during cardiac HR injuries.

Adaptive cellular memetic algorithms.

A cellular genetic algorithm (CGA) is a decentralized form of GA where individuals in a population are usually arranged in a 2D grid and interactions among individuals are restricted to a set neighborhood. In this paper, we extend the notion of cellularity to memetic algorithms (MA), a configuration termed cellular memetic algorithm (CMA). In addition, we propose adaptive mechanisms that tailor the amount of exploration versus exploitation of local solutions carried out by the CMA. We systematically benchmark this adaptive mechanism and provide evidence that the resulting adaptive CMA outperforms other methods both in the quality of solutions obtained and the number of function evaluations for a range of continuous optimization problems.