Histamine-degrading halophilic bacteria from traditional fish sauce: Characterization of Virgibacillus campisalis TT8.5 for histamine reduction.

Traditionally produced fish sauce can contain significant amounts of histamine. In some instances, the histamine concentration may be well above the limit recommended by the Codex Alimentarius Commission. The aim of this study was to discover new bacterial strains capable of growing under the stressful environmental conditions of fish sauce fermentation and metabolizing histamine. In this study, 28 bacterial strains were isolated from Vietnamese fish sauce products based on their ability to grow at high salt concentrations (23% NaCl) and tested for their ability to degrade histamine. Strain TT8.5 showed the highest histamine-degradation (45.1 ± 0.2% of initially 5 mM histamine within 7 days) and was identified as Virgibacillus campisalis TT8.5. Its histamine-degrading activity was shown to be localized intracellularly and the enzyme is a putative histamine dehydrogenase. The strain exhibited optimal growth and histamine-degrading activity at 37°C, pH 7%, and 5% NaCl in halophilic archaea (HA) histamine broth. It also showed pronounced histamine-degrading activity in HA histamine broth when cultivated at temperatures of up to 40 °C as well as in the presence of up to 23% NaCl. After treatment with immobilized cells, 17.6-26.9% of the initial histamine in various fish sauce products were reduced within 24 h of incubation, while no significant changes in other parameters of fish sauce quality were observed after this treatment. Our results indicate that V. campisalis TT8.5 is of potential interest to be applied in histamine degradation of traditional fish sauce.

Comparison between porphin, chlorin and bacteriochlorin derivatives for photodynamic therapy: Synthesis, photophysical properties, and biological activity.

The development of novel photosensitizers is a challenging task for photodynamic therapy (PDT). Twelve novel photosensitizers (PSs), including porphins (P1-4), chlorins (C1-4) and bacteriochlorins (B1-4) were synthesized. The bacteriochlorins exhibited the longest absorption wavelength (λmax = 736 nm), which is higher than that of porphins (λmax = 630 nm) and chlorins (λmax = 644 nm). In vitro photodynamic activities on Eca-109 human esophageal carcinoma cells were evaluated by standard assays and all PSs showed photodynamic activity. Among them, B2 displayed the highest phototoxicity and the lowest dark toxicity. In addition, B2 exhibited best photodynamic antitumor efficacy on BALB/c nude mice bearing Eca-109 cells tumor. Therefore, B2 is a powerful and promising antitumor photosensitizer for PDT.

PD98059 Protects Brain against Cells Death Resulting from ROS/ERK Activation in a Cardiac Arrest Rat Model.

The clinical and experimental postcardiac arrest treatment has not reached therapeutic success. The present study investigated the effect of PD98059 (PD) in rats subjected to cardiac arrest (CA)/cardiopulmonary resuscitation (CPR). Experimental rats were divided randomly into 3 groups: sham, CA, and PD. The rats except for sham group were subjected to CA for 5 min followed by CPR operation. Once spontaneous circulation was restored, saline and PD were injected in CA and PD groups, respectively. The survival rates and neurologic deficit scores (NDS) were observed, and the following indices of brain tissue were evaluated: ROS, MDA, SOD, p-ERK1/2/ERK1/2, caspase-3, Bax, Bcl-2, TUNEL positive cells, and double fluorescent staining of p-ERK/TUNEL. Our results indicated that PD treatment significantly reduced apoptotic neurons and improved the survival rates and NDS. Moreover, PD markedly downregulated the ROS, MDA, p-ERK, and caspase-3, Bax and upregulated SOD and Bcl-2 levels. Double staining p-ERK/TUNEL in choroid plexus and cortex showed that cell death is dependent on ERK activation. The findings in present study demonstrated that PD provides neuroprotection via antioxidant activity and antiapoptosis in rats subjected to CA/CPR.

The prevalence and patient characteristics of chronic obstructive pulmonary disease in non-smokers in Vietnam and Indonesia: An observational survey.

BACKGROUND AND OBJECTIVE: An estimated 25-40% of patients with chronic obstructive pulmonary disease (COPD) have never smoked. We investigated the prevalence and patient characteristics of COPD in non-smokers from Vietnam and Indonesia. METHODS: This population-based cross-sectional survey of participants from urban and rural Vietnam and Indonesia used a stratified multistage cluster sampling design, with sample and population weights applied to ensure representativeness. Participants were female or male (recruited in the ratio 2:1) non-smokers, 40 years or older and able to perform a spirometry test. Spirometry was performed at a single study visit. Other clinical information was collected via standardized questionnaires. RESULTS: The 1506 evaluable participants were approximately equally distributed between Vietnam and Indonesia, and rural and urban areas. Overall prevalence of COPD was found to be 6.9% (95% confidence interval (CI): 5.7-8.3), with almost three times higher prevalence in men than women (12.9% (95% CI: 9.1-18.0) vs 4.4% (95% CI: 3.0-6.5)). We found higher rates of COPD in Vietnam than Indonesia (8.1% (95% CI: 5.8-11.3) vs 6.3% (95% CI: 4.8-8.3)), with a particularly high prevalence in urban Vietnam (11.1% (95% CI: 8.1-15.1)). Very few participants (6%) diagnosed to have COPD during the study had been previously diagnosed with COPD. Respiratory symptoms and lower health-related quality of life were more common in participants with COPD. CONCLUSIONS: The prevalence of COPD in non-smoking individuals from rural and urban Vietnam and Indonesia was 6.9%, of which a significant proportion (94%) were previously undiagnosed.