Oleanane-type Saponins from Glochidion hirsutum and Their Cytotoxic Activities.

Five new oleanane-type saponins, hirsutosides A - E, were isolated from the leaves of Glochidion hirsutum (Roxb.) Voigt. Their structures were elucidated as 21ß-benzoyloxy-3ß,16ß,23,28-tetrahydroxyolean-12-ene 3-O-ß-d-glucopyranoside (1), 21ß-benzoyloxy-3ß,16ß,23,28-tetrahydroxyolean-12-ene 3-O-ß-d-glucopyranosyl-(1 â†’ 3)-ß-d-glucopyranoside (2), 21ß-benzoyloxy-3ß,16ß,23,28-tetrahydroxyolean-12-ene 3-O-6-acetyl-[ß-d-glucopyranosyl-(1 â†’ 3)]-ß-d-glucopyranoside (3), 21ß-benzoyloxy-3ß,16ß,23,28-tetrahydroxyolean-12-ene 3-O-ß-d-glucopyranosyl-(1 â†’ 3)-〈-l-arabinopyranoside (4), and 21ß-benzoyloxy-3ß,16ß,23-trihydroxyolean-12-ene-28-al 3-O-ß-d-glucopyranosyl-(1 â†’ 3)-α-l-arabinopyranoside (5). All isolated compounds were evaluated for cytotoxic activities on four human cancer cell lines, HepG-2, A-549, MCF-7, and SW-626 using the SRB assay. Compounds 1, 2, 4, and 5 showed significant cytotoxic activities against all human cancer cell lines with IC50 values ranging from 3.4 to 10.2 µm. Compound 3 containing acetyl group at glc C(6″) exhibited weak cytotoxic activity with IC50 values ranging from 47.0 to 54.4 µm.

First Report on the Occurrence and Antibiotic Resistance Profile of Colistin-Resistant Escherichia coli in Raw Beef and Cow Feces in Vietnam.

Colistin-resistant Escherichia coli (COE) has been recently recognized as a serious threat to animal and human health. This study aimed to determine the prevalence and antibiotic resistance profile of COE isolated from raw beef and cow feces in Vietnam. Our results showed that 16% (16/100) and 32% (32/100) of raw beef and cow feces samples were positive for COE, respectively. A total of 48 COE strains were isolated, with 16 originating from raw beef and 32 from cow feces samples. The antibiotic susceptibility test revealed that the COE isolates were highly resistant to ampicillin, tetracycline, florfenicol, trimethoprim/sulfamethoxazole, streptomycin, and nalidixic acid, with resistance rates ranging from 66.67% to 87.5%. In addition, 87.5% of the isolates were identified to be multidrug-resistant strains. Further molecular characterization indicated that all COE isolates carried the mcr-1 gene, with 16 of them also harboring blaCTX-M-55 genes. Taken together, the findings in this study demonstrate that raw beef and cow feces are important sources of COE, which can be potentially transmitted to humans through the food chain.

Prevalence, Molecular Characterization, and Antimicrobial Resistance Profiles of Shiga Toxin-Producing Escherichia coli Isolated from Raw Beef, Pork, and Chicken Meat in Vietnam.

Shiga toxin-producing Escherichia coli (STEC) is one of the most important foodborne pathogens, and the rise of antibiotic resistance to it is a significant threat to global public health. The purpose of this study is to investigate the prevalence, molecular characterization, and antibiotic resistance of STEC isolated from raw meat in Vietnam. The findings in this study showed that the prevalence of STEC in raw beef, pork, and chicken meat was 9.72% (7/72), 5.56% (4/72), and 1.39% (1/72), respectively. The STEC isolates were highly resistant to ampicillin (91.67%) and tetracycline (91.67%), followed by trimethoprim/sulfamethoxazole (83.33%), streptomycin (75%), and florfenicol (66.67%). The incidence of STEC virulence-associated genes, including stx1, stx2, eae, and ehxA, was 8.33% (1/12), 91.67% (11/12), 33.33% (4/12), and 58.33% (7/12), respectively. STEC serogroups O157, O26, and O111 were detected in 3 out of 12 STEC isolates. Two isolates were found to be ESBL producers carrying the blaCTX-M-55 gene, and three isolates were colistin-resistant strains harboring the mcr-1 gene. Notably, a STEC O111 isolate from chicken meat harbored both the blaCTX-M-55 and mcr-1 genes.

Antibiotic Resistance Profile and Bio-Control of Multidrug-Resistant Escherichia coli Isolated from Raw Milk in Vietnam Using Bacteriophages.

E. coli is an important zoonotic pathogen capable of causing foodborne illness and bovine mastitis. Bacteriophages have been increasingly considered a promising tool to control unwanted bacteria. The aim of this study is to determine the antibiotic resistance profile of E. coli isolated from raw milk and the efficacy of phage in controlling multidrug-resistant E. coli in raw milk. Antibiotic susceptibility testing showed the highest resistance rates of E. coli isolates to co-trime (27.34%) and ampicillin (27.34%), followed by streptomycin (25.18%), tetracycline (23.02%), and the lowest resistance rates to ciprofloxacin, gentamycin, and ceftazidime, all at a rate of 2.16%. All isolates were susceptible to meropenem. Of the 139 E. coli isolates, 57 (41.01%) were resistant to at least one antibiotic, and 35 (25.18%) were classified as MDR strains. Molecular characterization indicated that 5 (3.6%) out of the 139 isolates were STEC strains carrying stx1 gene. Seven (5.04%) isolates were phenotypically identified as ESBLEC, and four isolates (2.88%) were resistant to colistin. The results of the genotypic test revealed that four out of seven ESBLEC strains carried both blaTEM and blaCTX-M-1, two harbored blaTEM, and one possessed blaCTX-M-1, while mcr-1 was detected in all four colistin-resistant E. coli isolates. In particular, one isolated E. coli strain (EM148) was determined to be a multidrug-resistant strain simultaneously carrying blaTEM, blaCTX-M-1, and mcr-1. A total of eight phages were successfully recovered from raw milk. The application of phage PEM3 significantly reduced viable counts of multidrug-resistant host EM148 in raw milk by at least 2.31 log CFU/mL at both 24 °C and 4 °C.

Reference Value Fibrin Monomer in Healthy Children: A Cross-Sectional Study.

The objective of this study is to determine the fibrin monomer reference intervals in healthy children. This cross-sectional study was conducted in the Hematology Department at Vietnam National Children's Hospital (April 2023 to March 2024). Children without prior history of clotting disorders or anticoagulants use hospitalized in preparation for orthopedic surgery or inguinal hernia surgery were enrolled in the study. The fibrin monomer test method was the quantitative fibrin monomer test on the STA-R system (Diagnostica Stago™, France). Eighty-six children (58 males and 28 females) were enrolled in the study. The median (interquartile range, 2.5th-97.5th) fibrin monomer value of the study subjects was 2.56 (0.11-5.93) µg/mL, with no statistically significant difference in fibrin monomer values among the age groups of 1 month to 3 years, 3 years to 13 years, and 13 years to 18 years. This is the first study conducted in Vietnam to determine reference values of fibrin monomer in children. This information can help in the diagnosis and treatment of early hypercoagulation stage and disseminated intravascular coagulation in children.

Posterior reversible encephalopathy syndrome following septicemia in patient with myasthenia gravis.

Posterior reversible encephalopathy syndrome is a clinicoradiologic entity characterized by seizure, headaches, visual symptoms, impaired consciousness, and vasogenic cerebral edema of occipital and parietal lobes of the brain. Magnetic resonance imaging (MRI) is the diagnostic gold standard. The pathophysiology of posterior reversible encephalopathy syndrome is still unknown, but it is thought to be closely related to several medical conditions including hypertension, preeclampsia, eclampsia, immunosuppressive agents, transplantation, and sepsis. We report a rare case of posterior reversible encephalopathy syndrome in patient with myasthenia gravis and sepsis. A 22-year-old male was diagnosed with myasthenia gravis combined with sepsis due to pneumonia. During his recovery, the patient suffered multiple generalized convulsions and subsequent loss of consciousness. On cranial MRI, the abnormalities were observed with hyperintense within the subcortical white matter of the temporal, parietal, and bilateral occipital lobes on T2-weighted and T2 FLAIR. Reversibility of the symptoms and characteristic imaging findings led us to a diagnosis of posterior reversible encephalopathy syndrome. Early recognition and management of posterior reversible encephalopathy syndrome as a cause of encephalopathy in patients with septicemia and myasthenia gravis is necessary to prevent secondary complications in this condition.

Effect of Initial Vancomycin Dose and Creatinine Clearance on the Attainment of Target Trough Concentration in Children.

BACKGROUND: Vancomycin is a glycopeptide antibiotic that is used to treat serious grampositive infections. However, therapeutic drug monitoring for vancomycin is not performed routinely in Vietnam in clinical practices. Monitoring of serum vancomycin concentration or trough levels is necessary to ensure the efficacy and safety of vancomycin therapy. OBJECTIVE: This study aims to determine the impact of initial vancomycin dose and creatinine clearance on target trough attainment in hospitalized Vietnamese children. METHODS: A prospective study with patients who received vancomycin for at least three days was conducted. Subsequently, demographic data, clinical diagnosis, vancomycin dosage, and serum creatinine levels were recorded. The vancomycin trough level was collected and creatinine clearance and adjusted vancomycin doses were calculated. RESULTS: A total of 40 eligible patients were enrolled. Patients' mean age, body weight, and height were 1.4 years old, 9.8 kg, and 75.5 cm, respectively. The mean vancomycin dose was 55.83 ± 19.34 mg/kg/day. The mean creatinine clearance was 80.18 ± 29.14 ml/min. The median trough level was 11.09 (7.84 - 16.46) µg/ml. There was no significant difference in the mean initial and the adjusted vancomycin doses (p = 0.062). However, there were statistically significant differences of initial (p = 0.004) or adjusted doses (p = 0.016) between groups of creatinine clearance. The trough vancomycin concentration was not statistically significant (p = 0.406) between these groups. CONCLUSION: Target trough vancomycin level may be associated with creatinine clearance but did not proportionally correspond to the vancomycin dose. Therefore, monitoring vancomycin trough levels is necessary to achieve the target trough and to ensure vancomycin efficacy and safety in treating severely infected Vietnamese children.

A large lipoma of the descending colon: A rare case report.

Colon lipoma is a rare benign disease in the gastrointestinal tract with an incidence rate of approximately 0.035%-4.4%. The disease is often asymptomatic, so it is frequently discovered incidentally through endoscopy, computed tomography , or autopsy. When the tumor is over 2 cm in size, symptoms such as abdominal pain, bowel disorders, and bowel obstruction are common. Surgery is considered the mainstay of treatment for colonic lipomas. Furthermore, surgical (rather than endoscopic) resection is preferred for lipomas >2 cm to avoid complications such as bleeding and perforation. We report on a 61-year-old female patient who was diagnosed with a 4-cm descending colonic fat tumor detected by endoscopy and computed tomography and confirmed by pathology.

Titanium Nitride Nanodonuts Synthesized from Natural Ilmenite Ore as a Novel and Efficient Thermoplasmonic Material.

Nanostructures of titanium nitride (TiN) have recently been considered as a new class of plasmonic materials that have been utilized in many solar energy applications. This work presents the synthesis of a novel nanostructure of TiN that has a nanodonut shape from natural ilmenite ore using a low-cost and bulk method. The TiN nanodonuts exhibit strong and spectrally broad localized surface plasmon resonance absorption in the visible region centered at 560 nm, which is well suited for thermoplasmonic applications as a nanoscale heat source. The heat generation is investigated by water evaporation experiments under simulated solar light, demonstrating excellent solar light harvesting performance of the nanodonut structure.

Tuneable Giant Magnetocaloric Effect in (Mn,Fe)2(P,Si) Materials by Co-B and Ni-B Co-Doping.

The influence of Co (Ni) and B co-doping on the structural, magnetic and magnetocaloric properties of (Mn,Fe) 2 (P,Si) compounds is investigated by X-ray diffraction (XRD), differential scanning calorimetry, magnetic and direct temperature change measurements. It is found that Co (Ni) and B co-doping is an effective approach to tune both the Curie temperature and the thermal hysteresis of (Mn,Fe) 2 (P,Si) materials without losing either the giant magnetocaloric effect or the positive effect of the B substitution on the mechanical stability. An increase in B concentration leads to a rapid decrease in thermal hysteresis, while an increase in the Co or Ni concentration hardly changes the thermal hysteresis of the (Mn,Fe) 2 (P,Si) compounds. However, the Curie temperature decreases slowly as a function of the Co or Ni content, while it increases dramatically for increasing B concentration. Hence, the co-substitution of Fe and P by Co (Ni) and B, respectively, offers a new control parameter to adjust the Curie temperature and reduce the thermal hysteresis of the (Mn,Fe) 2 (P,Si) materials.

Two New Compounds from the Leaves of Glochidion obliquum.

Using combined chromatographic methods, two new compounds, 6ß,9ß:9,13-diepoxymegastig-4-en-3ß-ol (1), 5a,6a-epoxy D:C-friedoolean-8-en-3ß-ol (2) were isolated from the methanol extract of the leaves of Glochidion obliquum Decne. Their structures were elucidated by 1D- and 2D-NMR spectra and in comparison with those reported in the literature.