Matrix-assisted laser desorption ionization-time of flight mass spectrometry based identification of Edwardsiella ictaluri isolated from Vietnamese striped catfish (Pangasius hypothalamus)

Edwardsiella (E.) ictaluri is a major bacterial pathogen that affects commercially farmed striped catfish (Pangasius hypothalamus) in Vietnam. In a previous study, 19 strains of E. ictaluri collected from striped catfish were biochemically identified with an API-20E system. Here, the same 19 strains were used to assess the ability of matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS; applied using a MALDI Biotyper) to conduct rapid, easy and accurate identification of E. ictaluri. MALDI-TOF MS could directly detect the specific peptide patterns of cultured E. ictaluri colonies with high (> 2.0, indicating species-level identification) scores. MALDI Biotyper 3.0 software revealed that all of the strains examined in this study possessed highly similar peptide peak patterns. In addition, electrophoresis (SDS-PAGE) and subsequent immuno-blotting using a specific chicken antibody (IgY) against E. ictaluri revealed that the isolates had highly similar protein profiles and antigenic banding profiles. The results of this study suggest that E. ictaluri isolated from striped catfish in Vietnam have homologous protein compositions. This is important, because it indicates that MALDI-TOF MS analysis could potentially outperform the conventional methods of identifying E. ictaluri.

Effects of Physical Activity and Melatonin in a Rat Model of Depression Induced by Chronic Stress

PURPOSE: Stress, depending on its intensity and duration, results in either adaptive or maladaptive physiological and psychological changes in humans. Also, it was found that stressful experiences increase the signs of behavioral despair in rodents. On the other hand, exercise and melatonin treatment is believed to have many beneficial effects on health. Thus, this study was designed to evaluate the anti-depressant effects of physical activity and melatonin against chronic stress-induced depression in rats. METHODS: Adult male Sprague-Dawley(SD) rats(200-250g, 7 weeks of age) were subjected to depression induced by chronic stress. Chronic depression was induced with forced-swim stress (FSS) and repeated change of light-dark cycle for 4 weeks. In the last 2 weeks, some rats were confined in a cage enriched with a running wheel, seesaw and chewed a ball from 19:00 to 07:00 every day. Melatonin was injected intra-peritoneally (I.P), and the rats received intraperitoneal injections of melatonin (15 mg/kg). The Forced Swim Test (FST) was performed to evaluate the immobility behaviors of rats for a 5 min test. RESULTS: It was found that, the immobility time in FST was significantly (p<.05) lower in physical exercise (M=58.83+/-22.73) and melatonin (M=67.33+/-37.73) than in depressive rats (M=145.93+/-63.16) without physical activity. Also, TPH positive cell in dorsal raphe was significantly (p<.05) higher in exercise (M=457.38+/-103.21) and melatonin (M=425.38+/-111.56) than in depressive rats (M=258.25+/-89.13). CONCLUSION: This study suggests that physical activity and melatonin produces antidepressant-like effect on stress-induced depression in rats. So, physical exercise and melatonin may be a good intervention in depression patients.

Ultrasonographic findings of ovarian cystadenoma

The ultrasonographic findings of 49 ovarian cystadenomas were analized. The results were as follows: 1. Themost common age group was 3rd decade and most patients(83%) belong to active reproductive period. 2. In 80% ofserous cystadenoma the size of the tumor was ranged in 6–10cm in diameter. The large tumors of 16–20 cm indiameter were mostly mucinous cystadenomas. 3. Purely cystic appearance was the most common finding(40%) of serouscystadenoma and thick linear septation with and without solid component was the most common finding (38%) ofmucious cystadenoma. 4. Thick linear septation with solid component was not found inserous cystadenoma. 5. Welldefined nodular projection was found in 3 cases of serous cystadenoma but not identified in mucinous cystadenoma.