Inhibition of nitric oxide synthase increases synaptophysin mRNA expression in the hippocampal formation of rats

Synaptophysin is a protein involved in the biogenesis of synaptic vesicles and budding. It has been used as an important tool to investigate plastic effects on synaptic transmission. Nitric oxide (NO) can influence plastic changes in specific brain regions related to cognition and emotion. Experimental evidence suggests that NO and synaptophysin are co-localized in several brain regions and that NO may change synaptophysin expression. Therefore, the aim of the present work was to investigate if inhibition of NO formation would change synaptophysin mRNA expression in the hippocampal formation. Male Wistar rats received single or repeated (once a day for 4 days) i.p. injections of saline or l-nitro-arginine (l-NOARG, 40 mg/kg), a non-selective inhibitor of nitric oxide synthase (NOS). Twenty-four hours after the last injection the animals were sacrificed and their brains removed for ‘in situ’ hybridization study using ³⁵S-labeled oligonucleotide probe complementary to synaptophysin mRNA. The results were analyzed by computerized densitometry. Acute administration of l-NOARG induced a significant (p < 0.05, ANOVA) increase in synaptophysin mRNA expression in the dentate gyrus, CA1 and CA3. The effect disappeared after repeated drug administration. No change was found in the striatum, cingulated cortex, substantia nigra or nucleus accumbens. These results reinforce the proposal that nitric oxide is involved in plastic events in the hippocampus.     

Psychosocial correlates of alcohol intake among women aged 45 to 64 years: The Framingham Study

This study of 749 women, aged 45 to 64 years, investigates the psychological, behavioral, and social correlates of alcohol intake. These data from the Framingham Study are uniquely based on a community sample of women, which results in a normative study of drinking behavior in women. Two measures of alcohol intake were utilized in these analyses: (1) the frequency of alcohol intake over 1 week and (2) drinking vs abstaining from alcohol. Among this sample of women, increased socioeconomic status, worrying about aging, and being easily upset were positively associated with frequency of alcohol intake. The rigid attitude scale was the strongest discriminating variable for drinkers vs nondrinkers. Older women were more likely to be nondrinkers compared to younger women, however, among older women, being a homemaker was significantly associated with increased alcohol intake. Contrarily, younger women who were homemakers were more likely to be abstainers than women employed outside the home. As would be expected, cigarette smoking was associated with drinking alcohol.This research is dedicated in fond remembrance to our friend and colleague Joseph Stokes III, M.D.     

Analysis of human papillomavirus prevalence and TP53 polymorphism in head and neck squamous cell carcinomas

Head and neck squamous cell carcinoma is a disease associated with tobacco and alcohol abuse. There is evidence that the oncogenic human papillomavirus (HPV) may also be a risk for upper aerodigestive tract cancers. High-risk HPVs encode two early proteins, E6 and E7, that can bind to p53 and pRb, respectively, and induce its degradation or inactivation. The TP53 gene has a single polymorphism at codon 72 of exon 4 that encodes either arginine (Arg) or proline (Pro). The purpose of this study was to evaluate the role of HPV infection and TP53 polymorphism in head and neck cancer. We analyzed 50 tumors, as well swabs of oral mucosa from 142 control individuals, with a polymerase chain reaction technique. The prevalence of HPV in controls was 10.6% and in cancer specimens 16%. The frequency distribution of genotypes in controls was 50% Arg/Arg, 43% Arg/Pro and 7% Pro/Pro; in tumors, it was 52% Arg/Arg, 32% Arg/Pro, and 16% Pro/Pro. Contrary to the results of some studies on cervical cancer, no association between any TP53 genotype or allele and the development of head and neck cancer was observed, regardless of HPV status, except for the Pro/Pro genotype, which is associated with the absence of HPV. The arginine allele appears to protect against head and neck cancers. Also, the data showed that HPV infection results in no increased risk of developing head and neck tumors.     

Dopamine and serotonin: influences on male sexual behavior

Steroid hormones regulate sexual behavior primarily by slow, genomically mediated effects. These effects are realized, in part, by enhancing the processing of relevant sensory stimuli, altering the synthesis, release, and/or receptors for neurotransmitters in integrative areas, and increasing the responsiveness of appropriate motor outputs. Dopamine has facilitative effects on sexual motivation, copulatory proficiency, and genital reflexes. Dopamine in the nigrostriatal tract influences motor activity; in the mesolimbic tract it activates numerous motivated behaviors, including copulation; in the medial preoptic area (MPOA) it controls genital reflexes, copulatory patterns, and specifically sexual motivation. Testosterone increases nitric oxide synthase in the MPOA; nitric oxide increases basal and female-stimulated dopamine release, which in turn facilitates copulation and genital reflexes. Serotonin (5-HT) is primarily inhibitory, although stimulation of 5-HT(2C) receptors increases erections and inhibits ejaculation, whereas stimulation of 5-HT(1A) receptors has the opposite effects: facilitation of ejaculation and, in some circumstances, inhibition of erection. 5-HT is released in the anterior lateral hypothalamus at the time of ejaculation. Microinjections of selective serotonin reuptake inhibitors there delay the onset of copulation and delay ejaculation after copulation begins. One means for this inhibition is a decrease in dopamine release in the mesolimbic tract.     

Monitoring Information-Seeking Patterns and Obesity Prevalence in Africa With Internet Search Data: Observational Study

BackgroundThe prevalence of chronic conditions such as obesity, hypertension, and diabetes is increasing in African countries. Many chronic diseases have been linked to risk factors such as poor diet and physical inactivity. Data for these behavioral risk factors are usually obtained from surveys, which can be delayed by years. Behavioral data from digital sources, including social media and search engines, could be used for timely monitoring of behavioral risk factors.ObjectiveThe objective of our study was to propose the use of digital data from internet sources for monitoring changes in behavioral risk factors in Africa.MethodsWe obtained the adjusted volume of search queries submitted to Google for 108 terms related to diet, exercise, and disease from 2010 to 2016. We also obtained the obesity and overweight prevalence for 52 African countries from the World Health Organization (WHO) for the same period. Machine learning algorithms (ie, random forest, support vector machine, Bayes generalized linear model, gradient boosting, and an ensemble of the individual methods) were used to identify search terms and patterns that correlate with changes in obesity and overweight prevalence across Africa. Out-of-sample predictions were used to assess and validate the model performance.ResultsThe study included 52 African countries. In 2016, the WHO reported an overweight prevalence ranging from 20.9% (95% credible interval [CI] 17.1%-25.0%) to 66.8% (95% CI 62.4%-71.0%) and an obesity prevalence ranging from 4.5% (95% CI 2.9%-6.5%) to 32.5% (95% CI 27.2%-38.1%) in Africa. The highest obesity and overweight prevalence were noted in the northern and southern regions. Google searches for diet-, exercise-, and obesity-related terms explained 97.3% (root-mean-square error [RMSE] 1.15) of the variation in obesity prevalence across all 52 countries. Similarly, the search data explained 96.6% (RMSE 2.26) of the variation in the overweight prevalence. The search terms yoga, exercise, and gym were most correlated with changes in obesity and overweight prevalence in countries with the highest prevalence.ConclusionsInformation-seeking patterns for diet- and exercise-related terms could indicate changes in attitudes toward and engagement in risk factors or healthy behaviors. These trends could capture population changes in risk factor prevalence, inform digital and physical interventions, and supplement official data from surveys.     

The expectations and realities of nutrigenomic testing in australia: A qualitative study

BackgroundConsumer genomic testing for nutrition and wellness, (nutritional genomics), is becoming increasingly popular. Concurrently, health‐care practitioners (HPs) working in private practice (including doctors interested in integrative medicine, private genetic counsellors, pharmacists, dieticians, naturopaths and nutritionists) are involved as test facilitators or interpreters.ObjectiveTo explore Australian consumers’ and HPs’ experiences with nutrigenomic testing.MethodSemi‐structured in‐depth interviews were conducted using predominantly purposive sampling. The two data sets were analysed individually, then combined, using a constant comparative, thematic approach.ResultsOverall, 45 interviews were conducted with consumers (n = 18) and HPs (n = 27). Many of the consumer interviewees experienced chronic ill‐health. Nutrigenomic testing was perceived as empowering and a source of hope for answers. While most made changes to their diet/supplements post‐test, self‐reported health improvements were small. A positive relationship with their HP appeared to minimize disappointment. HPs’ adoption and views of nutrigenomic testing varied. Those enthusiastic about testing saw the possibilities it could offer. However, many felt nutrigenomic testing was not the only ‘tool’ to utilize when offering health care.DiscussionThis research highlights the important role HPs play in consumers’ experiences of nutrigenomics. The varied practice suggests relevant HPs require upskilling in this area to at least support their patients/clients, even if nutrigenomic testing is not part of their practice.Patient or public contributionAdvisory group included patient/public group representatives who informed study design; focus group participants gave feedback on the survey from which consumer interviewees were sourced. This informed the HP data set design. Interviewees from HP data set assisted with snowball sampling.