Comparison of mechanical and electrical activity and interstitial cells of Cajal in urinary bladders from wild-type and W/Wv mice

Background and purpose:

W/W^v and wild-type murine bladders were studied to determine whether the W/W^v phenotype, which causes a reduction in, but not abolition of, tyrosine kinase activity, is a useful tool to study the function of bladder interstitial cells of Cajal (ICC).

Experimental approach:

Immunohistochemistry, tension recordings and microelectrode recordings of membrane potential were performed on wild-type and mutant bladders.

Key results:

Wild-type and W/W^v detrusors contained c-Kit- and vimentin-immunopositive cells in comparable quantities, distribution and morphology. Electrical field stimulation evoked tetrodotoxin-sensitive contractions in wild-type and W/W^v detrusor strips. Atropine reduced wild-type responses by 50% whereas a 25% reduction occurred in W/W^v strips. The atropine-insensitive component was blocked by pyridoxal-5-phosphate-6-azophenyl-2′,4′-disulphonic acid in both tissue types. Wild-type and W/W^v detrusors had similar resting membrane potentials of −48 mV. Spontaneous electrical activity in both tissue types comprised action potentials and unitary potentials. Action potentials were nifedipine-sensitive whereas unitary potentials were not. Excitatory junction potentials were evoked by single pulses in both tissues. These were reduced by atropine in wild-type tissues but not in W/W^v preparations. The atropine-insensitive component was abolished by pyridoxal-5-phosphate-6-azophenyl-2′,4′-disulphonic acid in both preparations.

Conclusions and implications:

Bladders from W/W^v mice contain c-Kit- and vimentin-immunopositive ICC. There are similarities in the electrical and contractile properties of W/W^v and wild-type detrusors. However, significant differences were found in the pharmacology of the responses to neurogenic stimulation with an apparent up-regulation of the purinergic component. These findings indicate that the W/W^v strain may not be the best model to study ICC function in the bladder.     

Elevated manganese levels in blood and CNS in human prion disease

Prion disease or transmissible spongiform encephalopathies are neurodegenerative disorders of humans and other mammals. They are fatal and difficult to diagnose. Previous studies have suggested that some prion diseases cause elevation of manganese in the blood and brain. In the current study we analysed blood and brain samples from humans to determine whether elevation in manganese is a specific characteristic of Creutzfeldt-Jakob disease, the most common form of human prion disease. Analysis of manganese in the blood of normal humans showed that concentrations vary little with age or sex. Analysis of other diseases, including other neurodegenerative disease showed that only CJD showed an elevation in manganese and copper. Other diseases that showed elevated manganese included blood-brain barrier disorders and haemochromatosis. However, CJD could be easily distinguished from these diseases. This implies that increased blood manganese in prion disease is a highly specific characteristic of the disease.     

High sex ratio as a correlate of depression in Chinese men

BackgroundThere is a large and increasing excess of men in China, especially in poor rural areas, with millions now unable to marry. The study aimed to determine whether these high sex ratios influence the prevalence of depression.MethodsThe study was a cross-sectional survey, using a self-completion questionnaire, administered to adults of reproductive age in localities with widely varying sex ratios in three provinces: Zhejiang, Yunnan and Guizhou. Depression was measured using the Chinese version of the Beck Depression Inventory (BDI).ResultsA total of 7435 men and women aged 19–40 completed questionnaires. Moderate or severe depression was found in 17.6% of men and 17.0% of women, and suicide thoughts and wishes in 18.0% and 20.0% respectively. Independent correlates for depression and suicide ideation in men were high local sex ratio, rural residence, low education and poor economic status. Very high local sex ratio was the strongest independent determinant of depression in men.LimitationsThese include (1) selection bias: with just three provinces and a purposive sampling strategy, (2) reporting bias: the BDI score is arguably a crude measure for a complex psychological condition, and the veracity of responses to sensitive questions cannot be guaranteed, (3) information bias: county-level sex ratio figures may underestimate the actual sex ratio, especially in rural areas.ConclusionVery high sex ratios in parts of China are contributing to depression and suicidal tendencies in men, and women, but especially unmarried men. Proactive measures need to be taken to identify and treat vulnerable individuals.     

Predictors of successful labor induction with oral or vaginal misoprostol

Objective: To identify independent predictors of successful labor induction with oral or vaginal misoprostol.

Methods: Women enrolled in four previous randomized trials involving oral or vaginal misoprostol for cervical ripening and labor induction were included in the present cohort study, with dosing of 25–50?μg every 4 to 6?h vaginally (n?=?574) or 50?μg every 4?h orally (n?=?207). Multiple logistic regression was performed to identify factors independently associated with successful labor induction – defined as vaginal delivery within 12?h, vaginal delivery within 24?h and spontaneous vaginal delivery. Predictors of Cesarean birth and the need for only one dose of misoprostol were also identified. Variables included in the models were maternal age, weight, height, parity, gravidity, membrane status, route of misoprostol, gestational age, birth weight, and Bishop score and its individual components.

Results: Maternal age, height, weight, parity, birth weight, dilatation, effacement and cervical station were associated with vaginal delivery within 24?h of induction. Maternal age, height, weight, nulliparity, birth weight and route of misoprostol were associated with Cesarean birth, with oral misoprostol being associated with a lower rate of Cesarean birth. The need for only one dose of misoprostol was predicted by maternal height, weight, parity, gestational age, Bishop score and route of misoprostol.

Conclusion: Characteristics of the woman (height, weight, parity), the fetus (birth weight) and some of the individual components of the Bishop score, were associated with successful labor induction, with oral misoprostol being associated with a lower rate of Cesarean birth.     

A thematic cluster analysis of parents' online discussions about fussy eating

Food fussiness is associated with non‐responsive parent feeding practices, such as persuasive and instrumental feeding. Although most children described as ‘fussy eaters’ are likely exhibiting developmentally typical behaviours, up to half of the parents of children 2–5 years old express concerns. Concern for fussy eating may mediate the use of non‐responsive feeding practices and so must be addressed in parent feeding interventions. Therefore, it is critical to better understand parents'' concerns and how they may relate to feeding practices. This study aimed to explore how parents'' feeding practices and the social cognitive factors that may drive them clustered based on parents'' concern for fussy eating. Data were collected from parent discussions of fussy eating on a Reddit forum (80,366 posts). Latent Dirichlet allocation was used to identify discussions of fussy eating. Relevant posts (1542) made by users who identified as a parent of a fussy eater (n = 630) underwent qualitative coding and thematic analysis. Five clusters of parents were identified, ranging in size from 53 to 189 users. These were primarily characterised by parents'' degree of concern and feeding practices: (1) High concern, nonresponsive; (2) Concerned, nonresponsive; (3) Low concern, responsive; (4) Low concern, mixed strategies; (5) Low concern, indulgent. Parents who used responsive practices tended to be less concerned for fussy eating, have greater trust in their child''s ability to self‐regulate hunger, have longer‐term feeding goals, and exhibit greater ability for personal self‐regulation. Future research should further examine how these constructs may be leveraged in parent feeding interventions.     

The European Sero-Epidemiology Network 2: standardization of assay results for hepatitis B virus

The aim of the European Sero-Epidemiology Network 2 was to coordinate and standardize the serological surveillance of vaccine-preventable diseases in Europe. In this study, the standardization of hepatitis B virus (HBV) results is described. The 15 participating national laboratories tested a unique panel of 172 sera established by the Greek reference centre for HBV surface antigen (HBsAg), antibodies to HBsAg (anti-HBs) and/or to the HBV core antigen (anti-HBc) by assay methods of their choice. Country-specific quantitative measurements for anti-HBs and anti-HBc were transformed into common units using standardization equations derived by regressing each country's panel results against the reference centre's results, thus adjusting for interassay and interlaboratory variability. For HBsAg, a qualitative analysis (positive/negative) showed at least 99% agreement with the reference laboratory for all countries. By combining these standardized and qualitative results for the markers mentioned earlier, it was possible to achieve comparable estimates of the proportion of the population susceptible to HBV, vaccinated against HBV, with a past HBV infection, and with a current infection or chronic carrier state. Standardization is a very important tool that allows for international serological comparisons to assess the current vaccination policies and the progress of HBV control in Europe.