Toxicity assessment and vitellogenin expression in zebrafish (Danio rerio) embryos and larvae acutely exposed to bisphenol A,endosulfan, heptachlor,methoxychlor and tetrabromobisphenol A

Organochlorine pesticides and brominated flame retardants, such as tetrabromobisphenol A and polybrominated diphenyl ethers, pose an environmental hazard owing to their persistence, low solubility and estrogenic effects, and concerns have been raised regarding their effects on aquatic biota. In the present study, zebrafish embryos and larvae were used as a model to investigate the sublethal and lethal effects of three different organochlorine pesticides, namely methoxychlor, endosulfan and heptachlor, as well as the flame retardant tetrabromobisphenol A, and its precursor compound bisphenol A. Preliminary data for chemical exposure tests were obtained by determining the 96 h median effective concentration EC₅₀ (hatching rate) and 96 h median lethal concentration LC₅₀. Quantitative polymerase chain reaction was used to investigate the gene expression levels of the biomarker vitellogenin (vtg1) after 96 h exposures to 10, 25, 50 and 75% of the 96 h EC₅₀ value for embryos and 96 h LC₅₀ value for larvae. The use of vtg1 mRNA induction in zebrafish embryos and larvae was found to be a sensitive biomarker of exposure to these organic compounds, and was helpful in elucidating their adverse effects and setting water quality guidelines. Copyright © 2012 John Wiley & Sons, Ltd.     

Mycoplasma genitalium,an agent of reemerging sexually transmitted infections

M. genitalium is a reemerging microorganism, responsible for sexually transmissible infections (STIs), with prevalence which varies depending on the country and population group studied. We report here M. genitalium prevalence among the specimens received for STI diagnosis in our routine microbiological laboratory in the university hospital in Marseille, France. We tested 4 624 samples from 3 793 patients using qPCR for M. genitalium, C. trachomatis, N. gonorrheae, T. pallidum. Of these samples, 528 (13.6%) patients were tested positive for at least one pathogen and 126 (3.3%) were positive for M. genitalium. M. genitalium is the second most prevalent micro‐organism detected in women after C. trachomatis (10.4%) and the third most prevalent in men after C. trachomatis (5.1%) and N. gonorrhoeae (4.4%). We observed no significant differences between the prevalence of M. genitalium in vaginal, urethral and urine specimens (p = 0.9). Prevalence of M. genitalium is significantly higher in patients aged between 10–30 years (4.1%) compared to those aged between 30 and 50 years (2.7%) (p = 0.02, RR = 1.54 [1.06–2.24]) and patients over 50 years of age (1.1%) (p = 0.003, RR= 3.98 [1.47–10.8]). M. genitalium is a common agent of STI, therefore we suggest that this micro‐organism should be systematically tested during chronic, recurrent, or antibiotic resistant genital infections and in populations at high‐risk of STIs.     

Melatonin ameliorates low‐grade inflammation and oxidative stress in young Zucker diabetic fatty rats

The aim of this study was to investigate the effects of melatonin on low‐grade inflammation and oxidative stress in young male Zucker diabetic fatty (ZDF) rats, an experimental model of metabolic syndrome and type 2 diabetes mellitus (T2DM). ZDF rats (n = 30) and lean littermates (ZL) (n = 30) were used. At 6 wk of age, both lean and fatty animals were subdivided into three groups, each composed of 10 rats: naive (N), vehicle treated (V), and melatonin treated (M) (10 mg/kg/day) for 6 wk. Vehicle and melatonin were added to the drinking water. Pro‐inflammatory state was evaluated by plasma levels of interleukin‐6 (IL‐6), tumor necrosis factor‐α (TNF‐α), and C‐reactive protein (CRP). Also, oxidative stress was assessed by plasma lipid peroxidation (LPO), both basal and after Fe²⁺/H₂O₂ inducement. ZDF rats exhibited higher levels of IL‐6 (112.4 ± 1.5 pg/mL), TNF‐α (11.0 ± 0.1 pg/mL) and CRP (828 ± 16.0 µg/mL) compared with lean rats (IL‐6, 89.9 ± 1.0, P < 0.01; TNF‐α, 9.7 ± 0.4, P < 0.01; CRP, 508 ± 21.5, P < 0.001). Melatonin lowered IL‐6 (10%, P < 0.05), TNF‐α (10%, P < 0.05), and CRP (21%, P < 0.01). Basal and Fe²⁺/H₂O₂‐induced LPO, expressed as malondialdehyde equivalents (µmol/L), were higher in ZDF rats (basal, 3.2 ± 0.1 versus 2.5 ± 0.1 in ZL, P < 0.01; Fe²⁺/H₂O₂‐induced, 8.7 ± 0.2 versus 5.5 ± 0.3 in ZL; P < 0.001). Melatonin improved basal LPO (15%, P < 0.05) in ZDF rats, and Fe²⁺/H₂O₂‐ induced LPO in both ZL (15.2%, P < 0.01) and ZDF rats (39%, P < 0.001). These results demonstrated that oral melatonin administration ameliorates the pro‐inflammatory state and oxidative stress, which underlie the development of insulin resistance and their consequences, metabolic syndrome, diabetes, and cardiovascular disease.     

Reliability of the pattern hair loss classifications: A comparison of the basic and specific and Norwood–Hamilton classifications

Pattern hair loss (PHL) is the most common form of baldness in both sexes. The Norwood–Hamilton classification is the most commonly used classification worldwide, but it has many limitations. The basic and specific (BASP) classification was introduced as an improvement over the Norwood–Hamilton classification. Previous research was done to estimate the reliability of the Norwood–Hamilton classification and the result was unsatisfactory. However, the reliability of the BASP and Norwood–Hamilton classifications has not yet been compared. Eight dermatological specialists, 17 dermatological residents and 15 general physicians classified PHL in 100 sets of photographs using both the BASP and Norwood–Hamilton classifications. Intergroup reproducibility was evaluated by examining the match rate of the individual data in each group and the match rate between hair specialist and the other examiners. Intragroup repeatability was determined by calculating the match rate between the first and second studies. In terms of intergroup reproducibility of the match rate for individual data in each group, the basic type had the best agreement, the specific type had the second best, and the Norwood–Hamilton classification had the lowest match rate. In comparison, hair specialist and intragroup repeatability showed the same patterns. The BASP classification not only distinguishes all kinds of hair loss patterns, but also has better reproducibility and repeatability than the Norwood–Hamilton classification.