Antibiotic susceptibility of Vibrio parahaemolyticus isolated from prawns and oysters marketed in Zhanjiang, China.

To evaluate the antibiotic susceptibility of Vibrio parahaemolyticus from prawns and oysters marketed in Zhanjiang, Guangdong, China. 84 strains of V. parahaemolyticus were isolated from prawns and oysters sampled from 9 major markets. The results showed that 84 V. parahaemolyticus strains had the highest rate of antibiotic resistance to oxytetracycline (69.05 %, 58/84) and the lowest rate of antibiotic resistance to enrofloxacin (1.19 %, 1/84), ciprofloxacin (4.76 %, 4/84) and norfloxacin (7.14 %, 6/84) in quinolone. Meanwhile, 96.42 % of the strains showed multiple antibiotic resistance (MAR). PCR results showed that the resistance phenotype was closely related to the antibiotic resistance genes and efflux pump genes (p < 0.01), and the efflux pump gene was the key causing MAR. The combination of antibiotics significantly eliminated multidrug resistance. In addition, efflux pump inhibitors also reduce MAR. This study may provide information on antibiotic susceptibility, antibiotic resistance and strategies for the control of V. parahaemolyticus.

Priestia megaterium ASC-1 Isolated from Pickled Cabbage Ameliorates Hyperuricemia by Degrading Uric Acid in Rats.

Pickled cabbage, a traditional fermented food rich in functional microorganisms, can effectively control hyperuricemia and gout. In this study, a Priestia megaterium ASC-1 strain with strong uric acid (UA) degradation ability was isolated from pickled cabbage. After oral administration for 15 days, ASC-1 was stably colonized in the rats in this study. ASC-1 significantly reduced UA levels (67.24%) in hyperuricemic rats. Additionally, ASC-1 alleviated hyperuricemia-related inflammatory response, oxidative stress, and blood urea nitrogen. Intestinal microbial diversity results showed that ASC-1 restored intestinal injury and gut flora dysbiosis caused by hyperuricemia. These findings suggest that P. megaterium ASC-1 may be used as a therapeutic adjuvant for the treatment of hyperuricemia.

A model linking digital media dependence, exercise empowerment, and social physique anxiety among emerging adulthood college students.

Background/objective: Social physique anxiety (SPA) is a prevalent psychological issue among emerging adults, regardless of gender. Many studies have shown that high levels of SPA are associated with various negative consequences on both physical and mental well-being. Considering the potential severity of SPA's consequences and its high prevalence among emerging adults, it is imperative to investigate the factors and mechanisms that contribute to SPA in this population. Although prior studies have identified associations between emerging adulthood, digital media use, and SPA in young individuals, the underlying mechanisms remain unclear. The objective of this study is to examine the associations between SPA, emerging adulthood characteristics, digital media dependency, and exercise empowerment. Methods: In this cross-sectional study, Chinese college students were recruited using snowball sampling. The study utilized an online survey to assess SPA, emerging adulthood characteristics, digital media dependency, and exercise empowerment. The collected data was analyzed using path analysis. Results: A total of 1,661 Chinese college students (mean age = 19.63 ± 0.32 years, 44.97% male) were included in this study. The results showed that SPA exhibited positive correlations with responsibility and instability in emerging adulthood characteristics, digital media dependency, and exercise empowerment. Additionally, digital media dependency showed positive correlations with responsibility and instability, as well as with exercise empowerment. Furthermore, exercise empowerment demonstrated positive correlations with self-exploration, responsibility, instability, and possibilities in emerging adulthood characteristics. SPA can be directly influenced by digital media dependency, self-exploration, and instability. Furthermore, digital media dependency has a positive indirect impact on SPA through exercise empowerment. Similarly, self-exploration also has a positive indirect impact on SPA through exercise empowerment. On the other hand, instability has a negative indirect impact on SPA through exercise empowerment. Conclusion: This study provides new insights into the complex correlations with emerging adulthood characteristics, digital media dependency, exercise empowerment, and SPA. Instability, self-exploration in emerging adulthood characteristics, as well as digital media dependency, have the potential to influence SPA among college students through exercise empowerment Interventions and strategies aimed at addressing these psychological factors may prove beneficial in reducing SPA among emerging adults, especially college students.

Docosahexaenoic Acid Promotes Cd Excretion by Restoring the Abundance of Parabacteroides in Cd-Exposed Mice.

As a common harmful pollutant, cadmium (Cd) can easily enter the human body through the food chain, posing a major threat to human health. Gut microbiota play a key role in Cd absorption. Docosahexaenoic acid (DHA) is thought to have a potential role in the treatment of Cd poisoning. This study investigated the therapeutic effect and mechanism of DHA in Cd-exposed mice from the perspective of the gut microbiota. The results showed that DHA significantly increased the Cd content in feces and decreased the Cd accumulation in the organs of mice. The gut microbiota results showed that DHA significantly restored the abundance of Parabacteroides in the gut microbiota of Cd-exposed mice. Parabacteroides distasonis (P. distasonis), a representative strain of the Parabacteroides, also showed Cd- and toxicity-reduction capabilities. P. distasonis significantly restored the gut damage caused by Cd exposure. At the same time, P. distasonis reduced the Cd content in the liver, spleen, lung, kidneys, gut, and blood to varying degrees and significantly increased the Cd content in feces. The succinic acid produced by P. distasonis plays an important role in promoting Cd excretion in Cd-exposed mice. Therefore, these results suggest that P. distasonis may have a potential role in DHA-mediated Cd excretion in Cd-exposed mice.

Eu3+- and Tb3+-Based Coordination Complexes of Poly(N-Isopropyl,N-methylacrylamide-stat-N,N-dimethylacrylamide) Copolymer: Synthesis, Characterization and Property.

This contribution reports the syntheses, structural analyses and properties of europium (Eu3+)- and terbium (Tb3+)-based coordination complexes of poly(N-isopropyl,N-methylacrylamide-stat-N,N-dimethylacrylamide) (poly(iPMAm-stat-DMAm)) copolymer, named as poly-Eu(III) and poly-Tb(III), respectively. In greater detail, poly(iPMAm85-stat-DMAm15) is first prepared by random copolymerization of N-isopropyl,N-methylacrylamide (iPMAm) and N,N-dimethylacrylamide (DMAm) via group transfer polymerization (GTP). Next, poly(iPMAm85-stat-DMAm15) is used as the polymer matrix for chelating with Eu3+ and Tb3+ cations at its side amide groups, to produce poly-Eu(III) and poly-Tb(III). Their structural characterizations by FT-IR spectroscopy and XPS confirm the formation of polymeric complexes. The study on their fluorescence emission characteristics and luminescence lifetime demonstrates that Poly-Eu(III) shows four strong emission peaks at 578, 593, 622, and 651 nm, which are responsible for the electron transitions from the excited 5D0 state to the multiplet 7FJ (J = 0, 1, 2, 3) states, respectively, and poly-Tb(III) also displays four emission peaks at 489, 545, 588, and 654 nm, mainly due to the electron transitions of 5D4 → 7Fi (i = 6, 5, 4, 3). The luminescence lifetimes of poly-Eu(III) (τpoly-Eu(III)) and poly-Tb(III) (τpoly-Tb(III)) are determined to be 4.57 and 7.50 ms, respectively. In addition, in aqueous solutions, poly-Eu(III) and poly-Tb(III) are found to exhibit thermoresponsivity, with their cloud temperatures (Tcs) locating around 36.4 and 36.8 °C, respectively. Finally, the cytotoxicity study on the human colon carcinoma cells LoVo and DLD1 suggests that the luminescent Eu3+ and Tb3+ in the chelated state with poly(iPMAm-stat-DMAm) show much better biocompatibility and lower toxicity than their inorganic salts.

An HPLC-MS/MS Method Using a Multitoxin Clean up Column for Analysis of Seven Mycotoxins in Aquafeeds.

BACKGROUND: In Guangdong Province of China, the climate is very wet, so there are many different fungi living in aquatic feeds, which produce mycotoxins. These compounds contaminate agricultural products worldwide and present a great threat to human health. It is necessary to determine their contamination level in aquatic feeds. OBJECTIVE: A high performance liquid chromatography (HPLC) tandem mass spectrometry (MS/MS) method was developed for the quantitative analysis of aflatoxin B1, aflatoxin M1, T-2 toxin, HT-2 toxin, deoxynivalenol, ochratoxin, and zearalenone in fish and shrimp feed. METHODS: Samples were extracted with acetonitrile-water (3+1, v/v), and degreased with acetonitrile-saturated hexane. The extract was cleaned up with a multitoxin column. The target compounds were separated on a C18 chromatographic column and analyzed simultaneously by electrospray ionization mass spectrometry in both positive and negative ion mode. Detected compounds were quantified using the matrix-matched external standard method. RESULTS: Under the optimized conditions, good linearities for the analytes in the corresponding concentration range were obtained, with correlation coefficients (r2) higher than 0.9948. LODs ranged from 1.83 to 12.63 µg/kg, and LOQs ranged from 5.49 to 37.89 µg/kg. Average recoveries for the target mycotoxins at three spiked levels ranged from 80.5 to 116.5% with RSD ranging from 2.4 to 10.4%. Twenty-three real aquafeed samples were determined by this method, and seven kinds of toxins were detected. CONCLUSION: The results show that the developed method can be successfully applied for the simultaneous determination of mycotoxins in aquatic feeds. HIGHLIGHTS: Multitoxin purification columns proved to be a powerful technique for determining seven mycotoxins simultaneously. This method ensured simple sample pretreatment and less operation time. The established method was successfully applied to the analysis of seven mycotoxins species in aquatic feeds.

A combination of kissing molars, maxillary bilateral supernumerary teeth and macrodontia: a rare case report.

BACKGROUND: Supernumerary teeth (ST) is defined as an additional number of teeth compared to the normal dental formula. The prevalence rate of ST varies from 0.5 to 3.8% in the permanent dentition. When ST located distal to the third molar is acclaimed as distomolar. Moreover, kissing molar is an extremely scarce condition of distomolars, pointed in the opposite direction in a single follicular space. Meanwhile, macrodontia is also a rare shape anomaly characterized by a large crown and tapering root. CASE PRESENTATION: A 22-year-old Chinese man presented a combination of kissing molars, maxillary bilateral supernumerary teeth and macrodontia. Radiographically, two maxillary bilateral distomolars located at the buccal side of adjacent third molars. One mandibular distomolar with the adjacent third molar was contacted by occlusal surfaces while roots were pointed oppositely, which could be diagnosed as KM. Furthermore, the left mandibular third molar can be inferred to be a macrodontia, characterized by a large crown and tapering root. After a thorough investigation, we excluded the possibilities of systemic diseases and genetic inheritance. However, the etiology of this rare combination deserves to be further explored. CONCLUSION: The combination of kissing molars, maxillary bilateral supernumerary teeth and macrodontia is very rare, especially presented in the patient with no syndromes. As there were no complications with these conditions, long-term observation has been recommended for the patient. In addition, the true etiology need a further exploration.

Effects of T-2 toxin on digestive enzyme activity, intestinal histopathology and growth in shrimp Litopenaeus vannamei.

T-2 toxin (T-2), a naturally occurring mycotoxin that often accumulates in aquatic animals via contaminated feed, is toxic to animals, including humans. In this study, six groups of shrimp (n = 30 shrimps/group) were given T-2 in feed at concentrations of 0-12.2 mg/kg for 20 days. T-2 accumulation, intestinal histopathology, digestive enzyme activities and subsequent effects on shrimp are reported. Compared to the control, T-2 significantly reduced weight gain, specific growth rate, and survival. The histopathology of shrimp intestine showed concentration-dependent degenerative and necrotic changes in response to dietary T-2. Progressive damage to the microstructures of shrimp intestine occurred with increasing dietary T-2 concentrations, with initial inflammation of the mucosal tissue at T-2 concentrations of 0.5 and 1.2 mg/kg, progressing to disappearance of intestinal villi and degeneration and necrosis of the submucosa at 12.2 mg/kg. Intestinal amylase and protease activities increased at low T-2 concentrations but showed significant inhibition at high concentrations; however, the opposite trend occurred for lipase activity. Collectively, these results indicate that digestive enzyme activities and mucosal structures are markedly affected by exposure to T-2, and these may have contributed to the lower survival rate of shrimp.

Effects of T-2 toxin on histopathology, fatty acid and water distribution of shrimp (Litopenaeus vannamei) muscle.

T-2 toxin (T-2), one of the naturally occurring mycotoxins, often accumulates in aquatic animals from contaminated feed. Shrimp (n = 30 per group) were fed with different concentrations (0, 0.5, 1.5, 4.5 and 13.5 mg kg-1) of T-2 for 20 days. Changes in histopathology, fatty acid and water distribution of shrimp muscle were analyzed. Histopathology of shrimp muscle showed dose-dependent marked degenerative and necrotic changes on exposure to dietary T-2. The T-2 significantly (P < 0.05) affected the muscle fatty acid composition. ∑SFA, ∑MUFA and ∑PUFA initially decreased and then increased slowly in the high-dosed groups. C16:0, C18:1n-9 and C18:2n-6 were the main saturated fatty acid (SFA), monounsaturated fatty acid (MUFA) and polyunsaturated fatty acid (PUFA), respectively. Also, T-2 significantly affected water distribution in shrimp muscle. High doses of T-2 reduced free water content, resulting in a reduction in the water holding capacity and hence changes to the shrimp muscle quality. Collectively, these results illustrated that T-2 significantly affects the fatty acid and water distribution, and also muscle histopathology, all of which would result in a reduction in the quality and nutritional value of shrimp.

Biotransformation enzyme activities and phase I metabolites analysis in Litopenaeus vannamei following intramuscular administration of T-2 toxin.

T-2 toxin (T-2) is a type-A trichothecene produced by Fusarium that causes toxicity to animals. T-2 contamination of grain-based aquatic feed is a concern for the industries related to edible aquatic crustacean species such as the shrimp industry because it can lead to serious food safety issues. T-2, its metabolites, and selected phase I (EROD, CarE) and phase II (GST, UGT, SULT) detoxification enzymes in hemolymph and tissues were monitored at 0, 5, 10 15, 30, 45, and 60 min following T-2 intramuscular administration (3 mg/kg bw) in shrimp (Litopenaeus vannamei). Marked increases of EROD activity in hepatopancreas and CarE activity in hemolymph, gill, hepatopancreas and intestine were observed followed by increases in phase II enzymes (GST, UGT, SULT) in hepatopancreas, hemolymph, intestine and gill, which remained elevated for an extended period. Time-dependent decrease in shrimp tissue T-2 concentration was observed. HT-2 increased up to 15 min. Most other T-2 metabolites were detected but not T-2 tetraol. Enzyme responses on exposure to T-2 were tissue-specific and time-dependent. Detection results indicated that HT-2 may not be the only important metabolite in aquatic crustacean species. Further investigation into T-2 metabolite toxicity is needed to fully understand the food safety issues related to T-2.

Effect of T-2 toxin-injected shrimp muscle extracts on mouse macrophage cells (RAW264.7).

Following intramuscular injections of 0.1 mL, 3 mg kg-1 BW-1(1/10 LD50) T-2 toxin (T-2), the tissue concentration of T-2 in shrimp was quantitatively detected using LC-MS/MS. The biological half-time (t1/2) of T-2 in blood was 40.47 ± 0.24 min. The highest number of intramuscular T-2 shrimp could tolerate when given at blood t1/2 intervals was 4. The shrimps which were injected 5 T-2 died. The T-2 toxin highest accumulation was 0.471 ± 0.012 ng g-1 BW-1. The effect of toxic shrimp muscle subjected to different processing conditions (high pressure, trifluoroacetic acid, acid and alkali digestions, artificial digestive juice [to simulate exposure to gastric and intestinal juices]) on mouse macrophage cells (RAW267.4) were evaluated by the MTT assay. The inhibition ratio of 2% muscle extract on RAW267.4 was 85.70 ± 2.63%. The immunocytotoxicity of muscle extracts to RAW264.7 was highest in muscle extracts subjected to physical and chemical digestion (high pressure > NaOH > trifluoroacetic acid > 0.02 M HCl > 0.2 M HCl > controls), and also artificial digestion (artificial intestinal juice > artificial gastric juice > N type intestinal juice > N type gastric liquid > controls). Results showed that high-pressure and artificial intestinal juice were most effective in the release of modified T-2 to free T-2 thus enhancing toxicity. These results can be interpreted as measurement of T-2 in food being of little value because of enhanced toxicity of T-2-contaminated food as they pass through the gastrointestinal tract.

Selection and Evaluation of Indexes Commonly Used to Determine Contamination with T-2 Toxin in Pacific White Shrimp Litopenaeus vannamei by the Grey Relational Method.

The objectives of the present study were to evaluate the effects of different concentrations of the mycotoxin T-2 toxin in feed on muscle performance in the Pacific white shrimp Litopenaeus vannamei, evaluate indexes of physiological variables that indicate T-2 toxin contamination in the shrimp using the grey relational method, and determine the dose-response relationships between T-2 toxin and the indexes. Of the 6 physical, 7 biochemical, and 17 nutritional indexes examined, the values of the grey relational coefficients were highest for the hepatopancreas: body weight ratio (HBR), alanine aminotransferase (ALT) activity, and serine (SER) content (0.83, 0.68, and 0.82, respectively). Therefore, the HBR, ALT activity, and SER content were selected as appropriate indexes for contamination of Pacific white shrimp muscle with T-2 toxin. Based on their dose-response relationship curves, mean effective doses of 1.45, 1.69, and 1.33 mg of T-2 toxin/kg of feed were obtained for the HBR, ALT activity, and SER content, respectively. These results offer technical reference points for the evaluation and control of T-2 toxin in shrimp feed. Received April 28, 2016; accepted April 9, 2017.

Effects of T-2 Toxin on Pacific White Shrimp Litopenaeus vannamei: Growth, and Antioxidant Defenses and Capacity and Histopathology in the Hepatopancreas.

Modified-masked T-2 toxin (mT-2) formed during metabolism in edible aquatic animals may go undetected by traditional analytical methods, thereby underestimating T-2 toxicity. The effects of T-2 on growth and antioxidant capacity and histopathological changes in the hepatopancreas were studied in Pacific white shrimp Litopenaeus vannamei exposed for 20 d to 0, 0.5, 1.2, 2.4, 4.8, and 12.2 mg/kg of T-2 in their feed. The concentration of mT-2 in the hepatopancreas was detected by liquid chromatography-tandem mass spectrophotometry before and after trifluoroacetic acid (TFA) treatment that converted mT-2 to free T-2. A dose-dependent increase in mT-2 concentration was observed in the hepatopancreas. Dietary exposure to T-2 significantly decreased (P < 0.05) shrimp growth and survival rate compared with the controls. The malondialdehyde (MDA) concentration was significantly increased in shrimp exposed to feed with ≥2.4 mg/kg T-2 (P < 0.05). The antioxidant enzymes, superoxide dismutase (SOD) and glutathione peroxidase (GPx), total antioxidant capacity (T-AOC), and also glutathione (GSH) content increased in shrimp dosed with 2.4-4.8 mg/kg T-2 but declined at the highest dose (12.2 mg/kg), probably indicating an inability to cope with high concentrations of reactive oxygen species (ROS) as evident from a marked increase in MDA (P < 0.05) culminating in cellular toxicity. Histopathological changes in the hepatopancreas were dose dependent, with cell autophagy evident at the highest exposure dose. This is the first report in shrimp of a dose-dependent increase in ROS, SOD enzyme activity, and T-AOC at low T-2 exposures, and associated histopathological changes in the hepatopancreas, in response to dietary T-2. Received January 26, 2016; accepted October 9, 2016.

A simple and cost-saving phenotypic drug susceptibility testing of HIV-1.

It is essential to monitor the occurrence of drug-resistant strains and to provide guidance for clinically adapted antiviral treatment of HIV/AIDS. In this study, an individual patient's HIV-1 pol gene encoding the full length of protease and part of the reverse transcriptase was packaged into a modified lentivirus carrying dual-reporters ZsGreen and luciferase. The optimal coefficient of correlation between drug concentration and luciferase activity was optimized. A clear-cut dose-dependent relationship between lentivirus production and luciferase activity was found in the phenotypic testing system. Fold changes (FC) to a wild-type control HIV-1 strain ratios were determined reflecting the phenotypic susceptibility of treatment-exposed patient's HIV-1 strains to 12 HIV-1 inhibitors including 6 nucleoside reverse-transcriptase inhibitors (NRTIs), 4 non-nucleoside reverse transcriptase inhibitors (NNRTIs) and 2 protease inhibitors (PIs). Phenotypic susceptibility calls from 8 HIV-1 infected patients were consistent with 80-90% genotypic evaluations, while phenotypic assessments rectified 10-20% genotypic resistance calls. By a half of replacement with ZsGreen reporter, the consumption of high cost Bright-Glo Luciferase Assay is reduced, making this assay cheaper when a large number of HIV-1 infected individuals are tested. The study provides a useful tool for interpreting meaningful genotypic mutations and guiding tailored antiviral treatment of HIV/AIDS in clinical practice.

A novel derivatization approach for determination of ketamine in urine and plasma by gas chromatography-mass spectrometry.

A new method was developed for determination of ketamine (KT) in urine and plasma samples by derivatization and gas chromatography-mass spectrometry. In this article, KT was first derivatized with sodium nitrite to volatile N-nitrosamines under acidic condition. Then the derivative had been identified by the mass spectra. The derivatization conditions including the amount of hydrochloric acid, the amount of sodium nitrite, reaction temperature, reaction time and the extraction reagents were optimized. Calibration curves were linear in the range of 0.04-20 µg mL(-1) for KT, and the limit of detection (LOD) and limit of quantitation (LOQ) were 0.01 µg mL(-1) and 0.04 µg mL(-1), respectively. The results of recovery indicated that the method had good precision and reproducibility. Compared with existing derivatization methods, this method provided a rapid, convenient, effective and low-cost way for gas chromatography method of KT quantification.