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Silencing CTGF expression with siRNA demonstrates therapeutic potential to prevent liver fibrosis by inhibiting HSC activation with consequent extracellular matrix accumulation and the upregulation of TGF-beta1 gene expression.

ABSTRACT. Objectives. To explore the prevalence of irritable bowel syndrome (IBS) and its distribution characteristics of adolescents and children in China and its contributing factors.Methods. This study was a stratified, randomized study by clustering samples, which involved 5403 students whose age range was 6 to 18 years from 9 schools, and was conducted in Heilongjiang Province and Shanghai. All students studied were requested to fill in a questionnaire. IBS was diagnosed according to Rome II criteria.Results. The prevalence of IBS according to Rome II criteria in adolescents and children in China was 13.25%. The ratio of boys to girls was 1:1.8. There was a higher prevalence (14.02%) of IBS in Heilongjiang province than that (11.72%) in Shanghai. The prevalence in children 12 years and younger was not statistically significantly higher than that of adolescents 13 years and older (11.86% and 11.44%, respectively). The prevalence of IBS in minority students (21.15%) was not statistically significantly higher than that in Han race students (16.08%). Our study indicated that psychological factors, food habit, bad exterior environment, personal habits, and family conditions might be important contributing factors, and exposure to coldness (odds ratio: 2.83) is most prominent.Conclusion. IBS was a common disorder in adolescents and children in China. The prevalence of IBS in adolescents and children was different in different geographic areas. Our study indicated that IBS in adolescents and children might have possible relations with psychological factors, food habit, bad exterior environment, and family condition. I rritable bowel syndrome (IBS) is a common chronic functional gastrointestinal disorder. In the world, the epidemiologic studies indicate that IBS in adults is a common disorder that deserved more attention. In Western countries, the prevalence of IBS (Rome criteria) in adults was 8% to 23%; among them, 10% to 15% in European and North American countries and 11% to 17% in Oceania. In Africa, the rate was ϳ10%. In Asia, it was ϳ5%. 1-3 In view of the common understanding about adult IBS, some scholars in Western countries had undertaken many epidemiologic studies including the prevalence of IBS and its risk factors in adolescents, suggesting that IBS in a community-based adolescent population was also common. An epidemiologic study in Italy indicated that the prevalence of IBS in children aged birth to 12 years is 13.9%. 4 In the United states, Walker et al 5 tested the hypothesis that most children with recurrent abdominal pain could be classified into 1 or more of the symptom subtypes defined by the Pediatric Rome Criteria; moreover, 44.9% of children with recurrent abdominal pain were consistent with the Pediatric Rome Criteria for IBS. In Moscow, a study by Reshetnikov in students who were 14 to 17 years of age indicated that the prevalence of IBS was 14% to 24%; among them, 21% had to see doctors in different hospitals. Consequently, the medical costs were so high that many families could not affo...

Obesity and hyperinsulinism are known to be major stimuli of leptin production by adipose tissue, leading to increased leptin levels in the circulation. It has also been demonstrated that increased leptin production leads to satiety, possibly by decreasing the levels of neuropeptide Y (NPY) in the central nervous system (CNS). Because obesity and hyperinsulinism are also frequently associated with hypertension, we studied the effect of the intracerebroventricular (ICV) administration of leptin on mean arterial pressure (MAP), heart rate, vascular flows, and lumbar and renal sympathetic nerve activity (SNA). Normal Wistar rats were implanted with an ICV cannula and allowed to recover. On the day of the study, the animals were fasted and anesthetized with chloralose/urethane. Catheters were placed in a femoral artery and vein, and Doppler flow probes were placed around the iliac, renal, and superior mesenteric arteries for measurement of MAP, heart rate, and blood flows. In other experiments, lumbar SNA and renal SNA were recorded. ICV leptin administration resulted in an MAP that was slowly but progressively increasing. Blood flows decreased in the iliac and superior mesenteric arteries, but not in the renal artery. Leptin injection increased the lumbar SNA and renal SNA. The plasma glucose and insulin levels were not changed. We concluded that ICV leptin increases MAP by decreasing arterial blood flow to the skeletal muscle and the splanchnic vascular bed. This increased peripheral resistance is the result of an increased activity of the sympathetic nerves. We suggest that increased leptin may serve as a link in the triad of obesity and hyperinsulinism and hypertension.

A new synthetic strategy, the combination of living polymerization of ylides and ring-opening polymerization (ROP), was successfully used to obtain well-defined polymethylene-b-poly(e-caprolactone) (PM-b-PCL) diblock copolymers. Two hydroxyl-terminated polymethylenes (PM-OH, M n ¼ 1800 g mol À1 (PDI ¼ 1.18) and M n ¼ 6400 g mol À1 (PDI ¼ 1.14)) were prepared using living polymerization of dimethylsulfoxonium methylides. Then, such polymers were successfully transformed to PM-b-PCL diblock copolymers by using stannous octoate as a catalyst for ROP of e-caprolactone. The GPC traces and 1 H NMR of PM-b-PCL diblock copolymers indicated the successful extension of PCL segment (M n of PM-b-PCL ¼ 5200-10,300 g mol À1 ; PDI ¼ 1.06-1.13). The thermal properties of the double crystalline diblock copolymers were investigated by differential scanning calorimetry (DSC). The results indicated that the incorporation of crystalline segments of PCL chain effectively influence the crystalline process of PM segments. The low-density polyethylene (LDPE)/PCL and LDPE/polycarbonate (PC) blends were prepared using PM-b-PCL as compatibilizer, respectively. The scanning electron microscopy (SEM) observation on the cryofractured surface of such blend polymers indicates that the PM-b-PCL diblock copolymers are effective compatibilizers for LDPE/PCL and LDPE/PC blends. Porous films were fabricated via the breath-figure method using different concentration of PM-b-PCL diblock copolymers in CH 2 Cl 2 under a static humid condition. V C 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 49: 511-517, 2011