Objective:To investigate the effects of some culture conditions on production of asiaticoside from centella (Centella asiatica L. Urban) cells cultured in 5-L bioreactor.
Methods: The centell cell suspension culture was conducted in 5-L bioreactor to investigate the growth and asiaticoside accumulation under various conditions. Asiaticoside content was determined by HPLC analysis.
Results:The results showed that the cell growth and asiaticoside accumulation peaked after 24 d of culture at an agitation speed of 150 r/min and aeration rate of 2.5 L/min. The cell biomass reached a maximum value of 302.45 g fresh weight (31.45 g dry weight) and growth index of 3.03 with inoculum size of 100 g. However, asiaticoside content was the highest (60.08 mg/g dry weight) when culture was initiated with an inoculum size of 50 g.
Conclusions: The present study found the suitable conditions for growth of centella cells and their asiaticoside production in bioreactor.

Background: Fragile X Syndrome (FXS) is the second cause of Mental Retardation (MR) and the first cause of familiar MR. This syndrome affects up to 1/4000 men and 1/8000 women. X syndrome is often diagnosed by molecular biology technique such as RCR and Southern blot. Until now there is no study on FXS in Vietnam. Objectives: This study is aimed at: (1) Determine FXS among children with MR by technique of molecular biology. (2) Determine the mutation of FMR1 gen in families having children with FXS. Subject and Method: 214 children between 6 and 16 years of age (136 male and 78 female) with MR were analyzed FMR1 gen by PCR and Southern blot techniques. Families of children with FXS were also analyzed. Result and conclusion: This is the first study on FXS using the techniques of molecular biology in Vietnam. Identified 3 children with FXS, accounting for 1.4% of MR. Children with FXS and members with full mutation and premutation were found.
Fragile X syndrome ; FMR1 gene ; Mental retardation

Four Trichoderma strains (CH2, SH16, PQ34, and TN42) were isolated from soil samples collected from Quang Tri and Thua Thien Hue provinces in Vietnam. The strains exhibited high chitinolytic secretion. Strain PQ34 formed the largest zone of chitinase-mediated clearance (> 4 cm in diameter) in agar containing 1% (w/v) colloidal chitin. Analysis of the internal transcribed spacer regions of these strains indicated that they were Trichoderma asperellum. The molecular weights of the chitinases were approximately 42 kDa. Chitinase genes (chi42) of T. asperellum strains TN42, CH2, SH16, and PQ34 were 98~99% homologous to the ech42 gene of T. harzianum CB-Pin-01 (accession No. DQ166036). The deduced amino acid sequences of both T. asperellum strains SH16 and TN42 shared 100% similarity.
Agar ; Amino Acid Sequence ; Chitin ; Chitinase ; Colloids ; Molecular Weight ; Soil ; Sprains and Strains ; Trichoderma ; Vietnam

Surgical sperm retrieval (SSR) is currently one of the most common procedures in in vitro fertilization (IVF). However, a gap between the guidelines and routine clinical practice regarding antibiotic use in SSR, which might lead to antibiotic resistance, is a challenging problem worldwide. A cross-sectional survey was conducted from May 1, 2021, to July 15, 2021, to investigate antibiotic usage by medical professionals when performing SSR in IVF centers in Vietnam. The confidential questionnaire comprised 12 items, including characteristics of the study population, awareness of antimicrobial resistance, attitude toward prescribing antibiotics, and current practice of prescribing antibiotics when performing SSR. Surveys were completed by 30 of 45 registered IVF centers (66.7%). Among 67 physicians working at those centers, the age and work-experience years (mean ± standard deviation [s.d.]) were 38.6 ± 6.6 years and 11.2 ± 7.0 years, respectively. Over 60% of them held a degree in Obstetrics and Gynecology, and over four-fifths were men. Most respondents "often/very often/always" raised awareness of antimicrobial resistance to their patients (83.3%), but only half of them "often/occasionally" prescribed antibiotics to patients with SSR in cases where the prescription would be optional. About one-tenth of respondents followed the recommendation from the American Urological Association using "prophylaxis only" for SSR patients. For more invasive SSR, physicians tended to prescribe more complicated and sometimes inappropriate regimens. In conclusion, antibiotic usage in SSR was not always appropriate among IVF centers. Further studies may define specific recommendations for regimens, intervention strategies, and programs to promote appropriate antibiotic use for SSR patients among IVF specialists.
Humans ; Male ; Female ; Anti-Bacterial Agents/therapeutic use* ; Sperm Retrieval ; Cross-Sectional Studies ; Semen ; Surveys and Questionnaires ; Fertilization in Vitro ; Practice Patterns, Physicians'