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21.
We have previously demonstrated that the expression of calcineurin-like phosphoesterase domain containing 1 (CPPED1) decreases in adipose tissue (AT) after weight reduction. However, the function of CPPED1 in AT is unknown. Therefore, we investigated whether the change in CPPED1 expression is connected to changes in adipocyte glucose metabolism. First, we confirmed that the expression of CPPED1 decreased after weight loss in subcutaneous AT. Second, the expression of CPPED1 did not change during adipocyte differentiation. Third, CPPED1 knockdown with small interfering RNA increased expression of genes involved in glucose metabolism (adiponectin, adiponectin receptor 1, and GLUT4) and improved insulin-stimulated glucose uptake. To conclude, CPPED1 is a novel molecule involved in AT biology, and CPPED1 is involved in glucose uptake in adipocytes.Lifestyle modification improves glucose metabolism and results in a substantial reduction in the risk of type 2 diabetes in the long-term (1). In searching new putative genes related to obesity and type 2 diabetes, we have previously demonstrated a multitude of changes in adipose tissue (AT) gene expression in response to weight reduction in individuals with metabolic syndrome (2,3). Among the downregulated genes was calcineurin-like phosphoesterase domain containing 1 (CPPED1) (2); its function in AT is completely unknown.Therefore, we continued to study the role of CPPED1 in AT in more detail. Interestingly, the experiment using a Simpson-Golabi-Behmel syndrome (SGBS) cell strain demonstrated an impact of CPPED1 small interfering RNA (siRNA) on insulin-stimulated glucose uptake in mature adipocytes. Overall, the results demonstrate that CPPED1 is a novel molecule expressed in AT and is related to adipocyte function.  相似文献   
22.
There are more than 200,000 Canadians living with permanent pacemakers or implantable defibrillators, many of whom will require surgery or invasive procedures each year. They face potential hazards when undergoing surgery; however, with appropriate planning and education of operating room personnel, adverse device-related outcomes should be rare. This joint position statement from the Canadian Cardiovascular Society (CCS) and the Canadian Anesthesiologists' Society (CAS) has been developed as an accessible reference for physicians and surgeons, providing an overview of the key issues for the preoperative, intraoperative, and postoperative care of these patients. The document summarizes the limited published literature in this field, but for most issues, relies heavily on the experience of the cardiologists and anesthesiologists who contributed to this work. This position statement outlines how to obtain information about an individual's type of pacemaker or implantable defibrillator and its programming. It also stresses the importance of determining if a patient is highly pacemaker-dependent and proposes a simple approach for nonelective evaluation of dependency. Although the document provides a comprehensive list of the intraoperative issues facing these patients, there is a focus on electromagnetic interference resulting from electrocautery and practical guidance is given regarding the characteristics of surgery, electrocautery, pacemakers, and defibrillators which are most likely to lead to interference. The document stresses the importance of preoperative consultation and planning to minimize complications. It reviews the relative merits of intraoperative magnet use vs reprogramming of devices and gives examples of situations where one or the other approach is preferable.  相似文献   
23.

Purpose

We investigated the prevalence, natural course, and associated risk factors of habitual snoring (HS) and restless legs syndrome (RLS) over a period of 10?years among an aging population from their early sixties to their seventies.

Methods

A population-based follow-up study among all persons born in 1935 and living in the city of Oulu in northern Finland was conducted. In this study, we examined subjects who had participated in two subsequent surveys conducted in 1996?C1998 and 2007?C2008. The data were gathered by questionnaires, as well as by laboratory and clinical measurements.

Results

Altogether 457 (55%) of the 838 eligible subjects participated in both surveys. The prevalence of both RLS and HS decreased during the 10?years from 21% to 15% and from 26% to 19%, respectively. Half of those who snored in 1996?C1998 stopped snoring in 10?years time, and half of those who suffered from restless legs at least three times per week in 1996?C1998 suffered from this syndrome never or less than once a week in 2007?C2008. The 10-year incidence of new cases of both HS and RLS was 7%. Male gender predicted best the incidence of new HS in 10?years, while the Zung sum score as a marker of depressive symptoms and waist circumference predicted RLS.

Conclusions

Overall, the prevalence of both HS and RLS seems to diminish during aging. The causes behind this still remain unknown and should be investigated with more sophisticated methods.  相似文献   
24.
The necessity for postoperative inhaled nitric oxide (NO) therapy and predictive factors for that need were retrospectively analysed in 457 paediatric patients at risk of pulmonary hypertensive events following open-heart surgery for congenital heart disease. Inhaled NO was given postoperatively to 46% of the study group and to 23% of all patients undergoing open-heart surgery during the study period. Factors associated with increased need for postoperative NO were age <1 year, Down's syndrome, preoperative pulmonary hypertension and increased pulmonary vascular resistance. Using a multivariate model based on these factors, 73% of the patients who were given NO were identified. Thus, in a setting with unrestricted access to NO therapy, almost half of the patients with cardiac lesions that commonly give rise to postoperative pulmonary hypertension were given postoperative NO. Seventy-three percent of postoperative NO treatment was associated with a relatively small number of pre- and perioperative patient-related risk factors.  相似文献   
25.
The preoperative dose response to inhaled nitric oxide (NO) was compared with the need for and response to NO after cardiac surgery in patients with congenital heart defect and secondary pulmonary hypertension. In a preoperative vasodilator test with inhaled NO 20, 40 and 80 ppm and oxygen, mean pulmonary artery pressure (PAP) was at least 40 mmHg and/or the pulmonary vascular resistance index (PVRI) 4 Wood units. Preoperatively, NO 40 ppm and Fi02 0.9 reduced systolic pulmonary/systemic arterial pressure (PAPs/SAPs) from 0.89 (SD 0.10) to 0.80 (0.18) and pulmonary/systemic vascular resistance (PVR/SVR) from 0.26 (0.13) to 0.13 (0.08). Haemodynamic assessment was repeated in 11 patients postoperatively. NO treatment was started if PAPs/SAPs rose to 0.8 or the pulmonary oximetry fell below 40%. Postoperatively, eight of 11 patients, including 6 patients with Down's syndrome, needed NO. PAPs/SAPs decreased more than preoperatively: 48.5% vs 11.2, p = 0.0045. Pulmonary oximetry increased by 15.7%, p = 0.02. The degree of preoperative response to NO did not differ between the patients with postoperative pulmonary hypertension and the other children. Patients with early pulmonary hypertensive crisis (first 24 h; n = 6) had a higher PVRI (7.6 vs 4.4 Um2; p = 0.003) and PVR/SVR (0.34 VS 0.17; p = 0.02) preoperatively. Two patients died in pulmonary hypertensive crisis.  相似文献   
26.
Standardized and reproducible animal models are crucial in medical research. Rodents are commonly used in wound healing studies since, they are easily available, affordable and simple to handle and house. However, the most significant limitation of rodent models is that the wounds heal by contraction while in humans the primary mechanisms of healing are reepithelialization and granulation tissue formation. The robust contraction results in faster wound closure that complicates the reproducibility of rodent studies in clinical trials. We have developed a titanium wound chamber for rodent wound healing research. The chamber is engineered from two pieces of titanium and is placed transcutaneously on the dorsum of a rodent. The chamber inhibits wound contraction and provides a means for controlled monitoring and sampling of the wound environment in vivo with minimal foreign body reaction. This technical report introduces two modalities utilizing the titanium chambers in rats: (1) Wound in a skin island model and, (2) Wound without skin model. Here, we demonstrate in rats how the “wound in a skin island model” slows down wound contraction and how the “wound without skin” model completely prevents the closure. The titanium wound chamber provides a reproducible standardized models for wound healing research in rodents.  相似文献   
27.
Objectives. We sought to investigate whether functional abnormalities in coronary vasomotion exist in young adults by studying 15 men (age 31 ± 8 years [mean ± SD]) with familial hypercholesterolemia (FH) and a matched group of 20 healthy control subjects.

Background. Precursors of morphologic coronary artery disease are known to be present in adolescents and young adults with a high risk factor profile.

Methods. Myocardial blood flow was measured at the basal state and during dipyridamole-induced hyperemia using positron emission tomography and oxygen-15–labeled water.

Results. Serum total and low density lipoprotein cholesterol concentrations were higher in the patients than in the control subjects (mean ± SD): 7.7 ± 1.9 versus 5.3 ± 1.5 mmol/liter (298 ± 73 vs. 205 ± 58 mg/dl) and 6.1 ± 1.8 versus 3.5 ± 1.4 mmol/liter (236 ± 70 vs. 135 ± 54 mg/dl), respectively (both p < 0.001). The baseline myocardial blood flow was similar in the patients and control subjects: 0.92 ± 0.24 versus 0.83 ± 0.13 ml/g per min, respectively (p = 0.21). A significant increase in flow was observed in both groups after dipyridamole infusion, but the flow at maximal vasodilation was 29% lower in the patients: 3.19 ± 1.59 versus 4.49 ± 1.27 ml/g per min (p = 0.011). Consequently, coronary flow reserve (the ratio of hyperemia flow to basal flow) was 35% lower in the patients than in the control subjects: 3.5 ± 1.6 versus 5.4 ± 1.5 (p = 0.0008). Total coronary resistance during hyperemia was higher in the patients than in the control subjects: 36 ± 25 versus 21 ± 10 mm Hg/min per g per ml (p = 0.045). Coronary flow reserve was inversely associated with serum total cholesterol concentration: r = −0.43 (p = 0.009).

Conclusions. Coronary flow reserve is reduced in young men with FH, and, consequently, coronary resistance during hyperemia is increased. The results demonstrate very early impairment of coronary vasomotion in hypercholesterolemic patients.

(J Am Coll Cardiol 1996;28:1705–11)  相似文献   

28.
BACKGROUND: Few epidemiologic studies of dietary fiber intake and risk of coronary heart disease have compared fiber types (cereal, fruit, and vegetable) or included sex-specific results. The purpose of this study was to conduct a pooled analysis of dietary fiber and its subtypes and risk of coronary heart disease. METHODS: We analyzed the original data from 10 prospective cohort studies from the United States and Europe to estimate the association between dietary fiber intake and the risk of coronary heart disease. RESULTS: Over 6 to 10 years of follow-up, 5249 incident total coronary cases and 2011 coronary deaths occurred among 91058 men and 245186 women. After adjustment for demographics, body mass index, and lifestyle factors, each 10-g/d increment of energy-adjusted and measurement error-corrected total dietary fiber was associated with a 14% (relative risk [RR], 0.86; 95% confidence interval [CI], 0.78-0.96) decrease in risk of all coronary events and a 27% (RR, 0.73; 95% CI, 0.61-0.87) decrease in risk of coronary death. For cereal, fruit, and vegetable fiber intake (not error corrected), RRs corresponding to 10-g/d increments were 0.90 (95% CI, 0.77-1.07), 0.84 (95% CI, 0.70-0.99), and 1.00 (95% CI, 0.88-1.13), respectively, for all coronary events and 0.75 (95% CI, 0.63-0.91), 0.70 (95% CI, 0.55-0.89), and 1.00 (95% CI, 0.82-1.23), respectively, for deaths. Results were similar for men and women. CONCLUSION: Consumption of dietary fiber from cereals and fruits is inversely associated with risk of coronary heart disease.  相似文献   
29.
Brown adipose tissue (BAT) is able to generate heat and dissipate energy in response to cold exposure in mammals. It has recently been acknowledged that adult humans also have functional BAT, whose metabolic activity is reduced in obesity. In healthy humans, the cerebral mechanisms that putatively control BAT function are unclear. By using positron emission tomography (PET), we showed that cold-induced BAT activation is associated with glucose metabolism in the cerebellum, thalamus, and cingulate, temporoparietal, lateral frontal, and occipital cortices in lean participants, whereas no such associations were found under warm control conditions. The cold-induced increase in cerebral glucose metabolism was more robust in lean than obese participants. Cerebral glucose metabolism was not associated with skeletal muscle or white adipose tissue glucose uptake under warm or cold conditions. In conclusion, BAT metabolism was accompanied by the activation of specific cerebral regions, and this shows an uncharacterized role that the brain plays in the regulation of BAT function. In obese participants, the cold-induced response in cerebral activity was attenuated that provides a clue for obesity-induced impairment in BAT metabolism.  相似文献   
30.
Subendothelial mast cells have been implicated in the pathogenesis of allergic inflammation, in atherosclerosis, and in the regulation of vascular tone. Because endothelin-1 (ET-1) is an important regulator of vascular tone and has also been implicated in the pathogenesis of atherosclerosis, we studied the role of mast cells in the metabolism of endothelial cell-derived ET-1. In mast cell-endothelial cell cocultures, activation of the mast cells with ensuing degranulation was accompanied by the increased expression of ET-1 mRNA in the endothelial cells, yet the immunoreactive ET-1 protein in the coculture medium disappeared almost completely during the 24-hour coculture. Activation of the mast cells with the ensuing degranulation resulted in proteolytic degradation of ET-1 by the 2 neutral proteases, chymase and carboxypeptidase A, of the exocytosed mast cell granules. With synthetic ET-1 and purified mast cell granule enzymes, efficient degradation of ET-1 by chymase and carboxypeptidase A was verified. These in vitro results imply a novel role for mast cell-derived neutral proteases in ET-1 metabolism and suggest that activated subendothelial mast cells are important local regulators of ET-1 metabolism.  相似文献   
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