Relaxant effect of ghrelin on guinea pig isolated tracheal smooth muscle: role of epithelial NO and PGE2.

This study aimed at investigating the potential ghrelin relaxing effect on guinea pig isolated tracheal smooth muscle (TSM). Using an in vitro experimental approach, the physiological role of the airway epithelium on smooth muscle relaxation has been investigated by analyzing the dose-response curves for carbachol- or histamine-induced contractions on epithelium intact versus denuded tracheal tissue. The relaxant effect of ghrelin (5-200 µmol/L) then investigated on carbachol-contracted, non-sensitized, and ovalbumin (OVA)-sensitized guinea pig TSM with an intact or denuded epithelium. The isolated TSMs from identical guinea pigs were incubated in Krebs solution aerated with 95% O2 and 5% CO2 through an automated tissue organ bath system (n = 6 for each group). The ghrelin relaxation mechanism was assessed by adding L-NAME, indomethacin, and YIL-781 for GHS-R1 into the tissue chamber. The spasmogens carbachol and histamine have shown a significantly higher contracting effect on epithelium-denuded than in epithelium-intact TSM confirmed by the significantly higher mean pEC50 of both agonists on the epithelium-denuded trachea (p < 0.05). Ghrelin has shown a concentration-dependent relaxing effect on carbachol-contracted TSM (r = 0.96, p = 0.00). The effect was more evident in the intact non-sensitized than in epithelium-denuded or OVA-sensitized groups (p < 0.05). Preincubation with nitric oxide (NO) and prostaglandin E2 (PGE2) inhibitors has significantly reduced the ghrelin-induced relaxation on epithelium-intact TSM suggesting an epithelium-dependant mechanism. However, GHS-R1a antagonist has also succeeded to reduce ghrelin relaxant effect, which needs further clarification. Ghrelin proved to have a potential TSM relaxant effect possibly through epithelium-dependant mechanisms involving NO and PGE2.

Epidemiology of group A rotavirus infection after the introduction of monovalent vaccine in the National Immunization Program of Saudi Arabia.

This study aimed to investigate the prevalence of group A rotavirus (RVA) gastroenteritis and the distribution of the RVA genotypes as well as to determine a possible change in the age of occurrence of the RVA infection in the first 2 years after Rotarix® vaccine introduction in Saudi Arabia. This descriptive study included 850 hospitalized children <5 years of age with acute gastroenteritis (AG) between October 2013 and September 2015. Overall, 78 (9.2%) children were positive for RVA during the study period with a positivity rate ranging from 11.3% in the first year of the study to 6.8% in the second year. G1 (47.4%) was the predominant G type, followed by G2 (28.2%) and G9 (10.3%). The most common P type was P[8] (69.2%) followed by P[4] (25.6%). The decrease in the prevalence of G1P[8] from 51% to 37.1% was associated with an increase in the prevalence of G2P[4] from 21.6% to 33.3% during the 2-year study period. This study demonstrated a significant decrease in the prevalence of RVA-AG cases in the first 2-year period after vaccine introduction, especially in the age group between 1 and 12 months, and a reduction in the circulation of G1P[6]. The parallel rise and spread of G2P[4] in post-vaccination period might pose an impact to long-term vaccine efficacy. Continued surveillance studies in different Saudi regions are crucial to document the effectiveness of Rotarix® vaccine and evaluate the potential emergence of rare/novel RVA genotypes. J. Med. Virol. 89:429-434, 2017. © 2016 Wiley Periodicals, Inc.

Gestational Exposure to Synthetic Steroid Hormones Impaired Sperm Quantity and Quality in Wistar Rats.

This study was designed to investigate the effect of prenatal exposure to synthetic sex steroid on sperm quantity and quality, relative testicular and epididymal weights, and reproductive hormones level in adult Wistar rats. Forty male Wistar rats were divided into two groups: a test group (n = 20) that included mature rats that were born to dams exposed to gestational treatment with hydroxyprogesterone and a control group (n = 20) that included mature rats born to untreated dams. Compared to the control group, the test group showed a significant reduction in the sperm count, viability and motility, relative testicular and epididymal weights together with increased abnormal spermatozoa (p < 0.001). The reproductive hormonal assay revealed significantly lower serum testosterone and higher levels of FSH and LH among the test groups compared to the control (p < 0.05 for all). Prenatal exposure to synthetic progesterone negatively affected sperm production and function, relative testicular and epididymal weights, and reproductive hormone levels.

Parents' Knowledge, Attitudes and Practices on Antibiotic Use by Children.

BACKGROUND AND OBJECTIVE: Deficient knowledge on antibiotics causes misuse. This study aimed to investigate parents' knowledge, attitudes and practices on antibiotic use by children in various cities of Saudi Arabia. METHODS: This cross-sectional study was carried out using a previously validated questionnaire. The questionnaire was translated into Arabic and hosted on Google Forms. Parents of children aged ≤14 years, whose contact details were available with the author, were contacted and requested to participate in the study. For those who agreed to participate, the Google Forms link was shared through WhatsApp between July and August 2016. The respondents were also encouraged to share the link with contacts who had children aged ≤14 years. Descriptive and inferential statistical analyses were performed. RESULTS: In total, 544 parents responded from various cities of Saudi Arabia. Of these, about 75% were males (mean age = 49.9 years) and the majority (~68%) had a university degree and above. In the 6 months preceding the study, 431 respondents had taken their children to physicians. Of these, only 7.2% reported not being prescribed any antibiotics, whereas 66.8% were prescribed an oral antibiotic one or two times and 26% were more than three times. In terms of prescription, 373 respondents (68.6%) purchased antibiotics without a prescription, whereas 171 (31.4%) purchased it only after obtaining a prescription. However, only seven (1.3%) followed instructions regarding antibiotic usage, whereas 50% did not receive any advice from their doctor regarding use. All demographic characteristics, except gender and residence, were found to have significant effect on parents' knowledge on antibiotic use (P < 0.05). CONCLUSION: This study found that in various cities of Saudi Arabia, parents' knowledge, attitudes and practices on antibiotics for their children are poor. These findings highlight the need for parental education programs regarding antibiotic use and for implementing more stringent regulations on antibiotic prescription.