Hypocretin/orexin selectively increases dopamine efflux within the prefrontal cortex: involvement of the ventral tegmental area.

Hypocretins (HCRTs) modulate a variety of behavioral and physiological processes, in part via interactions with multiple ascending modulatory systems. Further, HCRT efferents from the lateral hypothalamus innervate midbrain dopamine (DA) nuclei, and DA cell bodies express HCRT receptors. Combined, these observations suggest that HCRT may influence behavioral state and/or state-dependent processes via modulation of DA neurotransmission. The current studies used in vivo microdialysis in the unanesthetized rat to first characterize the effect of intracerebroventricular infusion of HCRT-1 (0.07, 0.7 nmol) on extracellular levels of DA within the prefrontal cortex (PFC) and nucleus accumbens (Acc). Electroencephalographic/electromyographic measures of sleep-wake state were collected along with select behavioral measures (eg locomotor activity, grooming). HCRT-1 dose-dependently increased PFC dialysate DA levels, and these increases were closely correlated with increases in time spent awake. In contrast, Acc DA levels were unaffected. Additional studies examined whether HCRT-1 acts directly within the ventral tegmental area (VTA) to selectively increase PFC DA efflux and modulate behavioral state. Unilateral infusion of HCRT-1 (0.1, 1.0 nmol) within the VTA increased PFC, but not Acc, DA levels. Importantly, intra-VTA infusion of HCRT-1 increased the time spent awake and grooming. Moreover, HCRT-induced increases in both time spent awake and time spent grooming were significantly correlated with post-infusion PFC DA levels. The current observations predict a prominent modulatory influence of HCRT on PFC-dependent cognitive and affective processes that results, in part, from actions within the VTA. Additionally, these observations suggest that the activation of VTA DA neurons contributes to the behavioral state-modulatory actions of HCRT.     

Prevalence and risk behaviors of Chinese men who seek same-sex partners via the internet in Hong Kong.

To examine the prevalence of Internet sex networking among men who have sex with men (MSM) in Hong Kong and risk behaviors associated with the behavior, a telephone survey of 15,230 Hong Kong Chinese men aged 18-60 was conducted. Of the 283 active MSM (having engaged in some MSM behaviors in the last 6 months) identified, 17.7% had networked for MSM partners via the Internet in the last 6 months. Younger age (odds ratio [OR] for age < or = 25 vs. age >25 = 4.67, 95% confidence interval [CI] = 2.35-9.28) and being an anal-sex MSM (OR = 4.72, 95% CI=2.36-9.44) were independent predictors of Internet sex networking. Being an Internet sex networker was associated with some risk behaviors such as having contracted a sexually transmitted disease (adjusted OR = 4.79, 95% CI = 1.34-17.11), having had > or = 3 MSM partners (adjusted OR = 4.74, 95% CI = 2.20-10.23), and having engaged in anal sex (adjusted OR = 3.95, 95% CI = 1.89-8.23). HIV prevention programs for MSM should thereby include Internet-based interventions.     

Ultrasound imaging of the lower urinary tract after successful tension-free vaginal tape (TVT) procedure.

OBJECTIVES: To evaluate changes in the mobility of the whole urethra, in the proximal urethra (funneling) and in the thickness of the urinary bladder wall, after a successful tension-free vaginal tape (TVT) procedure. METHODS: This prospective longitudinal study included 52 women with urodynamically confirmed stress urinary incontinence who had undergone a successful TVT procedure. Ultrasound examination was performed before the TVT procedure and at a median of 3 (range, 3-6) months after surgery. For all women, the changes to the urethra and urinary bladder induced by surgery were examined. For three mobility groups (low, intermediate and high urethral mobility before surgery) we compared the changes induced by the operation and the typical position and mobility of the tape. RESULTS: The position of the urethra at rest was not influenced by surgery. The operation significantly decreased the mobility of all parts of the urethra during Valsalva. The absolute changes of the vector of the urethral movement differed according to the mobility group (average decrease, 6 mm; decrease for women with low, intermediate and high mobility, respectively, 2-3 mm, 4-6 mm and 9 mm). The change in relative mobility was the same in all groups. The operation decreased funneling (width and depth) during maximal Valsalva. After surgery there was an increase in the thickness of the bladder wall (by 0.64 and 0.73 mm, respectively, at the anterior part and trigone). CONCLUSIONS: A successful TVT procedure did not influence the position of the urethra at rest but significantly decreased the mobility of the urethra during Valsalva and also decreased funneling at maximal Valsalva.     

Effects of long-term treatment with resveratrol and subcutaneous and oral estradiol administration on the pituitary-thyroid-axis.

The lack of estrogen during menopause is associated with various symptoms including osteoporosis, cardiovascular diseases, and menopausal symptoms. For many years, conventional hormone replacement therapy has been successfully used to treat these conditions. However, in light of recent studies that draw attention to potential hazards of conventional HRT, various attempts were undertaken to search for alternatives of classical HRT. Phytoestrogens are supposed to ameliorate various discomforts associated with menopause. Resveratrol (RES) is present in red wine, grapes and peanuts and has been implicated in cardioprotection and prevention of adverse side effects observed after regular HRT. As the pituitary-thyroid axis is a target of estrogen action, we first assessed the effects of E2 administration on thyroid hormone stimulating hormone releasing hormone (TRH)-induced thyroid stimulating hormone (TSH) secretion from pituitary cell cultures in vitro. Our data reveal that E2 treatment augments the TRH-induced TSH secretion. We furthermore designed a long-term study of three months to assess the effects of subcutaneous and oral administration of 17beta-estradiol (E2), as well as the actions of RES on the pituitary-thyroid axis in ovariectomized (OVX) female rats. Our results demonstrate that serum levels of 1.0 and 8.1 microM RES lead to a significant increase in total serum triiodthyronine (T3) levels. OVX induces TSHbeta mRNA in the adenohypohysis and E2 treatment attenuates this effect. Treatment of rats with subcutaneous implants of E2 does not affect the pituitary-thyroid axis, whereas orally applied E2 benzoate (E2B) increases plasma TSH and total thyroxine (T4) in OVX rats. In all animals, we could not detect changes in thyroid morphology as assessed by hematoxylin-eosin (HE) and Perjod-Acid Schiff's (PAS) staining.     

Incidence of asthma and net change in symptoms in relation to changes in obesity.

The incidence of asthma has been reported to be associated with obesity. An alternative analysis, of net change in prevalence, does not require exclusion of those with asthma at baseline. Follow-up data were obtained from 9,552 participants in the European Community Respiratory Health Survey and the Swiss cohort Study on Air Pollution and Lung Disease in Adults. Incidence of asthma was analysed by proportional hazards regression, and net changes in symptoms and asthma status by generalised estimating equations, by obesity group. Incidence and net change in ever having had asthma were greater in females than in males, and in participants who remained obese compared with those who were never obese (hazard ratio 2.00, 95% confidence interval 1.25-3.20; excess net change 2.8%, 0.4-5.3% per 10 yrs). The effect of being obese on net change in diagnosed asthma was greater in females than in males, but for net change in wheeze without a cold it was greater in males. The present results are consistent with asthma being more frequently diagnosed in females, especially obese females. These findings may help to explain the reports of a stronger association between asthma and obesity in females than in males.     

Periodontal mechano-sensory responses following trauma to permanent incisor teeth in children

Abstract –  The aim of this study was to investigate mechano-sensory responses of injured and uninjured incisor teeth. Twenty-five children who had experienced dental trauma, together with age- and gender-matched controls, were studied prospectively. Touch thresholds of incisor teeth from both groups were determined using calibrated sets of von Frey hairs (force range 0.5–10.0 g in 0.5 g increments) using a forced choice staircase method. Forces were applied perpendicular to the buccal enamel surfaces along the midline, 2 mm from the incisal edge. Touch threshold was defined as the lowest force detected in three out of the five occasions. Following statistical analysis, P  < 0.05 was considered significant. At initial examination, the touch threshold values of 25 traumatised teeth were significantly greater than the untraumatised controls ( P  < 0.001), and these values approached those of the control teeth over 3–12 months ( P  > 0.05). Dental trauma was associated with increased touch thresholds in permanent incisor teeth, with recovery toward healthy control values usually occurring between 3–12 months.     

Preservation of Bile Ductules Mitigates Bile Duct Loss

The finer branches of the biliary tree (FBBT) contain a regenerative compartment. We hypothesized that preservation of the FBBT together with its microvasculature will lead to recovery of biliary damage and prolonged preservation of bile ductules during the development of chronic liver allograft rejection. The interlobular bile ducts, portal bile ductules and extraportal biliary cells with and without microvessels were studied in sequential biopsies in five patients who fulfilled the Banff criteria of early chronic rejection (CR) (imminence group). Biopsies of CR patients (n = 12) served as controls. Biopsies were double immunostained with CD34 (microvessels) and cytokeratin 7 (biliary structures). Proliferation and proangiogenic activity were assessed with Ki67 and VEGF-A immunostaining. Severe damage of bile ducts in the imminence group did not progress to significant bile duct loss. This was associated with a high proliferative activity in all biliary structures and preservation of the microvascular compartment. VEGF-A expression was increased in all but the reperfusion biopsies. In conclusion, both regenerative activity of the FBBT and an intact microvascular compartment are associated with less damage of the biliary tree and could therefore be prerequisites for biliary regeneration.     

Tacrolimus Combined with Two Different Dosages of Sirolimus in Kidney Transplantation: Results of a Multicenter Study

Tacrolimus combined with mycophenolate mofetil (MMF) is an effective regimen in kidney transplantation. This study compared the efficacy of combining tacrolimus and two different dosages of sirolimus with an established tacrolimus-MMF regimen. Each day in addition to tacrolimus, 325 patients received 2 mg sirolimus (TAC-SRL2 mg), 325 patients received 0.5 mg sirolimus (TAC-SRL0.5 mg) and 327 patients 1 g MMF (TAC-MMF). The initial tacrolimus dose was 0.2 mg/kg/day. Sirolimus patients received loading doses of 6 or 1.5 mg, and daily doses of 2 or 0.5 mg thereafter. Steroid administration was identical for all groups. The incidence of biopsy-proven acute rejection was lower in the TAC-SRL2 mg group (15.7%) compared with the TAC-SRL0.5 mg (25.2%, p = 0.003) and the TAC-MMF groups (22.3%, p = 0.036). Six-month graft survival was 91.0% (TAC-SRL2 mg), 92.6% (TAC-SRL0.5 mg) and 92.4% (TAC-MMF); the respective values for patient survival were 98.1%, 97.8% and 97.9%. Thirty-four patients (10.5%), 19 patients (5.8%) and 16 patients (4.9%) in the TAC-SRL2 mg, TAC-SRL0.5 mg and TAC-MMF groups, respectively, discontinued the study because of adverse events. Hyperlipemia was reported more often in the TAC-SRL2 mg group (24.0%) compared with 19.4% (TAC-SRL0.5 mg) and 11.0% (TAC-MMF; p < 0.05). Combining 2 mg sirolimus/day with tacrolimus results in lower rates of acute rejection, but a higher incidence of adverse events.