Overwintering of West Nile virus in Southern California

West Nile virus (family Flaviviridae, genus Flavivirus, WNV) invaded southern California during 2003, successfully overwintered, amplified to epidemic levels, and then dispersed to every county in the state. Although surveillance programs successfully tracked and measured these events, mechanisms that allowed the efficient overwintering and subsequent amplification of WNV have not been elucidated. Our current research provided evidence for three mechanisms whereby WNV may have persisted in southern California during the winters of 2003-2004 and 2004-2005: 1) continued enzootic transmission, 2) vertical transmission by Culex mosquitoes, and 3) chronic infection in birds. WNV was detected in 140 dead birds comprising 32 species, including 60 dead American crows, thereby verifying transmission during the November-March winter period. Dead American crows provide evidence of recent transmission because this species always succumbs rapidly after infection. However, WNV RNA was not detected concurrently in 43,043 reproductively active female mosquitoes comprising 11 species and tested in 1,258 pools or antibody in sera from 190 sentinel chickens maintained in 19 flocks. Although efficient vertical transmission by WNV was demonstrated experimentally for Culex tarsalis Coquillett infected per os, 369 females collected diapausing in Kern County and tested in 32 pools were negative for WNV. Vertical transmission was detected in Culex pipiens quinquefasciatus Say adults reared from field-collected immatures collected from Kern County and Los Angeles during the summer transmission period. Chronic infection was detected by finding WNV RNA in 34 of 82 birds that were inoculated with WNV experimentally, held for >6 wk after infection, and then necropsied. Frequent detection of WNV RNA in kidney tissue in experimentally infected birds >6 wk postinfection may explain, in part, the repeated detection of WNV RNA in dead birds recovered during winter, especially in species such as mourning doves that typically do not die after experimental infection. In summary, our study provides limited evidence to support multiple modes of WNV persistence i n southern California. Continued transmission andvertical transmission by Culex p. quinquefasciatus Say seem likely candidates for further study.     

An educational intervention to men for reducing environmental tobacco smoke exposure in their pregnant wives

Objective: To determine the effect of education based on health belief model (HBM) on the level of their pregnant wives’ environmental tobacco smoke exposure (ETSE).

Methods: This interventional randomized study was conducted on 60 cigarette smoking men who have exposed their pregnant wives to smoke during of their pregnancy. The HBM constructs and weekly ETSE were evaluated by using questionnaire. The intervention group received education with emphasis on the risks of cigarette’s smoke on the pregnancy. Then right after the training and 6 weeks after that, HBM constructs and 6 weeks after the training the weekly ETSE were evaluated again.

Results: Results showed a significant difference between the mean of perceived susceptibility, perceived benefits and barriers at intake and 6 weeks after the intervention in the intervention group. Also, the level of perceived susceptibility/severity and perceived barriers in both groups were significantly different 6 weeks after the intervention compared to intake time. The ETSE was significantly lower in the intervention group 6 weeks after the intervention in comparison to before the intervention and also to the control group.

Conclusions: This study showed that education husbands would relatively improve their health beliefs and reduce the ETSE of their pregnant wives.     

Regulation of platelet guanylyl cyclase by collagen: evidence that Glycoprotein VI mediates platelet nitric oxide synthesis in response to collagen

The molecular regulation of nitric oxide synthase (NOS) in blood platelets is an uncharacterised area of platelet biology. We investigated the mechanism of collagen-stimulated NO synthesis in platelets. Our aim was to identify the key collagen receptor and downstream signalling mechanisms linking collagen to NOS activation. Collagen and the GpVI-specific platelet activator collagen-related peptide (CRP-XL) stimulated NO synthesis, as evidenced by increased [(3)H]L-citrulline production, and cyclic GMP (cGMP) formation. After platelet activation by collagen and CRP-XL was normalised, we found no differences in NOS activation or cGMP formation in response to these agonists. Blocking the interaction of collagen with integrin alpha(2)beta(1), a second collagen receptor, failed to affect NOS activation by collagen. These data indicate that collagen-induced NO synthesis is linked to GpVI activation. cGMP formation in response to collagen and CRP-XL required increased intracellular Ca(2+), Src family kinases, phosphatidylinositol 3-kinase (PI3-K) and protein kinase C. By comparison, Gp VI-independent cGMP formation induced by thrombin was Src kinase-dependent, but was independent of PI3-K and PKC. Thus the mechanisms of collagen- and CRP-XL-induced NOS activation were identical, but distinct from that of thrombin. Platelet activation in response to collagen leads to secretion of adenosine diphosphate (ADP) and thromboxane A(2) (TxA(2)). Our results demonstrate that collagen-stimulated cGMP synthesis was enhanced significantly by platelet-derived ADP and TxA(2). These results reveal that collagen stimulates platelet NOS activation through a specific Ca(2+)-dependent GpVI receptor signalling cascade, and demonstrate that collagen-induced cGMP accrual requires the release of secondary platelet agonists.     

The efficacy of sour tea (Hibiscus sabdariffa L.) on selected cardiovascular disease risk factors: A systematic review and meta‐analysis of randomized clinical trials

This study sought to summarize clinical evidence of sour tea (Hibiscus sabdariffa L.) administration on cardiovascular disease risk factors. PubMed, Scopus, Institute for Scientific Information Web of Science, and Google Scholar were systematically searched from inception to June 2019 to identify randomized clinical trials, which assessed the effect of sour tea consumption on lipid profiles, fasting plasma glucose, and blood pressure in adult populations. Mean and standard deviation for each parameter were extracted to calculate effect size. Cochrane Collaboration tools were used to evaluate risk of bias assessment. A total of seven randomized clinical trials consisting 362 participants were included in the meta‐analysis. Pooled effect size demonstrated that sour tea consumption significantly reduces fasting plasma glucose (?3.67 mg/dl, 95% confidence interval, CI [?7.07, ?0.27]; I² = 37%), systolic blood pressure (?4.71 mmHg, 95% CI [?7.87, ?1.55]; I² = 53%), and diastolic blood pressure (?4.08 mmHg, 95% CI [?6.48, ?1.67]; I² = 14%). Although no significant effect was observed on triacylglycerol, total cholesterol, and high‐density lipoprotein cholesterol following sour tea consumption, a trend toward a significant reduction was found in low‐density lipoprotein cholesterol serum concentrations (p = 0.08). This systematic review and meta‐analysis suggests that sour tea consumption could have beneficial effect in controlling glycemic status and blood pressure among adult population.     

The impact of electronic education on metabolic control indicators in patients with diabetes who need insulin: a randomised clinical control trial

Aims and objectives. To determine the impact of electronic education on metabolic control indicators in patients with diabetes who were insulin dependent. Background. Education can play an important role in controlling diabetes. Electronic (web‐based, telehealth) education may be an efficient way to improve the patients’ ability to control this disease. Design. Randomised clinical control study. Methods. The participants in this clinical study were 48 insulin‐dependent patients referred to diabetes centres in Shiraz, Iran. Serum concentrations of haemoglobin A_1C, fasting blood sugar, triglycerides and high‐density and low‐density lipoprotein cholesterol were measured. Then the participants were divided randomly into control and experimental groups (n = 24). Participants in the experimental group received a specially designed electronic education programme for twelve weeks. The main components of the programme were a consultation service, quick answers to patients’ questions, contact with the healthcare team and educational materials. At the end of the intervention period, all serum values were measured again in both groups. The data were compared using spss v 13·5 software. Results. Serum concentrations of haemoglobin A_1C (p < 0·001) and low‐density lipoprotein cholesterol (p < 0·002) were significantly lower in the intervention group. Conclusion. The electronic education programme was useful in lowering two metabolic indicators of diabetes. Relevance to clinical practice. Electronic education can be associated with increased health and patient satisfaction, and can eliminate the need to train personnel.