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951.
Vascular endothelial growth factor (VEGF) is a critical promoter of blood vessel growth during embryonic development and tumorigenesis. To date, studies of VEGF antagonists have primarily focused on halting progression in models of minimal residual cancer. Consistent with this focus, recent clinical trials suggest that blockade of VEGF may impede cancer progression, presumably by preventing neoangiogenesis. However, VEGF is also a key mediator of endothelial-vascular mural cell interactions, a role that may contribute to the integrity of mature vessels in advanced tumors. Here, we report that high-affinity blockade of VEGF, using the recently described VEGF-Trap, abolishes mature, preexisting vasculature in established xenografts. Eradication of vasculature is followed by marked tumor regression, including regression of lung micrometastases. Thus, the contribution of relatively low levels of VEGF to vessel integrity may be critical to maintenance of even very small tumor masses. Potent blockade of VEGF may provide a new therapeutic option for patients with bulky, metastatic cancers.  相似文献   
952.
This study evaluated the prevalence of obstructive sleep apnea‐related symptoms and assessed the relationship with obesity or unusual sleep postures in Down syndrome patients in Japan. We obtained the demographic characteristics, sleep postures, and obstructive sleep apnea‐related symptoms experienced by 90 people as reported by their caregivers. Although 71% reported snoring and 59% arousals, obstructive sleep apnea‐related symptoms were not significantly different between obese and non‐obese participants. The youngest age group had the fewest obstructive sleep apnea‐related symptoms, especially symptoms of snoring. The odds for arousal, nocturia, and apnea tended to be higher in the unusual sleep‐postures group. Unusual sleep postures were most frequent in the group 6–15 years of age. People with Down syndrome might sleep in unusual postures to avoid upper airway obstruction caused by other anatomical factors. For nurses and other health professionals working in mainstream service, it is important to screen all persons with Down syndrome for symptoms suggestive of obstructive sleep apnea, particularly those six years of age and older, and to refer them for further evaluation for sleep disorders.  相似文献   
953.
954.
OBJECTIVE—Dietary patterns in Western populations have been linked to type 2 diabetes, but the role of diet in Japanese remains unclear. We investigated the association between major dietary patterns and glucose tolerance status as measured by A1C in Japanese adults.RESEARCH DESIGN AND METHODS—The groups of subjects were comprised of 3,243 men and 4,667 women who participated in the baseline survey of an ongoing cohort study on lifestyle-related diseases in Fukuoka, Japan. Dietary patterns were derived by using principal-component analysis of the consumption of 49 food items, ascertained by a food-frequency questionnaire. Logistic regression analysis was used to estimate sex-specific odds ratios (ORs) of elevated A1C (≥5.5%), with adjustment for potential confounding variables.RESULTS—The Westernized breakfast pattern characterized by frequent intake of bread but infrequent intake of rice was inversely related to A1C concentrations (Ptrend = 0.02 in both men and women); the multivariate-adjusted ORs for the highest versus lowest quintiles were 0.60 (95% CI 0.43–0.84) and 0.64 (0.46–0.90) for men and women, respectively. The seafood dietary pattern was positively associated with A1C concentrations in men only (Ptrend = 0.01). Neither the healthy nor high-fat dietary pattern was related to A1C.CONCLUSIONS—A dietary pattern featuring frequent intake of white rice may deteriorate glucose metabolism in Japanese men and women, and the salty seafood dietary pattern may have a similar effect in men.The prevalence of type 2 diabetes is increasing worldwide (1). Likewise, the Japanese, who have experienced rapid economic growth during the past several decades, now have a high prevalence of type 2 diabetes (2). However, this situation seems peculiar given that obesity, a strong determinant of the disease (3), is much less common among Japanese than among Western populations (4,5). It has been postulated that the Japanese are predisposed to type 2 diabetes because of their low levels of insulin secretion and sensitivity, which may be determined by both genetic and environmental factors (4,5). The investigation of a Japanese diet in relation to type 2 diabetes may provide a clue to the issue.The relation of specific foods and nutrients such as vegetables (6), dietary fiber (7), and glycemic load (8) to risk of type 2 diabetes has been examined in many studies, but few have addressed the association with dietary patterns. Although the effect of a single nutrient, food, or food group on disease risk and morbid conditions has often been investigated, such an effect is difficult to assess in observational studies because foods and nutrients are consumed in combination, and their complex effects are likely to be interactive or synergistic (9). To overcome problems relating to the close intercorrelation among foods or nutrients, analysis of dietary patterns has gained much interest. A dietary pattern is a comprehensive variable that integrates consumption of several foods or food groups and is expected to have a greater impact on disease risk than any single nutrient (9). Studies in Western populations have suggested that risk of type 2 diabetes is associated inversely with prudent or healthy dietary patterns (1012) and positively with a Western dietary pattern (1114). To the best of our knowledge, however, only one study reported an association between a Japanese dietary pattern and type 2 diabetes (15). The aim of the present study was, therefore, to investigate dietary patterns in relation to glucose tolerance status as measured by A1C concentrations in Japanese adults.  相似文献   
955.
After mechanical cleaning in oral care, eliminating residual oral contaminants has an important role in preventing their aspiration, especially in individuals with weak airway protection. We examined the effectiveness of wiping the oral cavity after oral care on eliminating contaminants in 31 patients who were hospitalized in our neurology inpatient unit. The amount of bacteria on the tongue, palate, and buccal vestibule was counted before and just after oral care, after eliminating contaminants either by rinsing with water and suction or by wiping with mouth wipes, and 1 h after oral care. Oral bacteria amounts were decreased significantly by both elimination procedures after oral care. These findings suggest that wiping with mouth wipes is as effective as mouth rinsing to decrease bacteria following oral care. With a lower risk of contaminant aspiration, wiping may be a suitable alternative to rinsing, especially in dysphagic individuals.  相似文献   
956.
Autotaxin (ATX) is a tumour cell motility-stimulating factor originally isolated from melanoma cell supernatants. ATX is identical to lysophospholipase D, which produces a bioactive lipid mediator, lysophosphatidic acid (LPA), from lysophosphatidylcholine. ATX is overexpressed in various malignancies, including Hodgkin lymphoma, and ATX may stimulate tumour progression via LPA production. The present study measured the serum ATX antigen levels in patients with haematological malignancies using a recently developed automated enzyme immunoassay. The serum ATX antigen levels in patients with B-cell neoplasms, especially follicular lymphoma (FL), were higher than those in healthy subjects. Serum ATX antigen levels in FL patients were associated with tumour burden and changed in parallel with the patients' clinical courses. The serum ATX antigen levels were little affected by inflammation, unlike the soluble interleukin-2 receptor and beta2-microglobulin levels. As expected, the plasma LPA levels in FL patients were correlated with the serum ATX antigen levels. Given that leukaemic tumour cells from FL patients expressed ATX, the shedding of ATX from lymphoma cells probably leads to the elevation of serum ATX antigen levels. Our results suggest that the serum ATX antigen level may be a promising and novel marker for FL.  相似文献   
957.
It is unclear how hepatic adiponectin resistance and sensitivity mediated by the adiponectin receptor, AdipoR2, contributes to the progression of nonalcoholic steatohepatitis (NASH). The aim of this study was to examine the roles of hepatic AdipoR2 in NASH, using an animal model. We fed C57BL/6 mice a methionine-deficient and choline-deficient (MCD) diet for up to 8 weeks and analyzed changes in liver pathology caused by either an AdipoR2 short hairpin RNA-expressing adenovirus or an AdipoR2-overexpressing adenovirus. Inhibition of hepatic AdipoR2 expression aggravated the pathological state of NASH at all stages: fatty changes, inflammation, and fibrosis. In contrast, enhancement of AdipoR2 expression in the liver improved NASH at every stage, from the early stage to the progression of fibrosis. Inhibition of AdipoR2 signaling in the liver diminished hepatic peroxisome proliferator activated receptor (PPAR)-alpha signaling, with decreased expression of acyl-CoA oxidase (ACO) and catalase, leading to an increase in lipid peroxidation. Hepatic AdipoR2 overexpression had the opposite effect. Reactive oxygen species (ROS) accumulation in liver increases hepatic production of transforming growth factor (TGF)-beta1 at all stages of NASH; adiponectin/AdipoR2 signaling ameliorated TGF-beta-induced ROS accumulation in primary cultured hepatocytes, by enhancing PPAR-alpha activity and catalase expression. CONCLUSION: The adiponectin resistance and sensitivity mediated by AdipoR2 in hepatocytes regulated steatohepatitis progression by changing PPAR-alpha activity and ROS accumulation, a process in which TGF-beta signaling is implicated. Thus, the liver AdipoR2 signaling pathway could be a promising target in treating NASH.  相似文献   
958.
Rapid nongenomic actions of aldosterone independent of mineralocorticoid receptors (MRs) on vascular tone are divergent. Until now, the rapid nongenomic actions of aldosterone on vascular tone of coronary artery and cardiac function in the in vivo ischemic hearts were not still fully estimated. Furthermore, although aldosterone can modulate protein kinase C (PKC) activity, there is no clear consensus whether PKC is involved in the nongenomic actions of aldosterone on the ischemic hearts. In open chest dogs, the selective infusion of aldosterone into the left anterior descending coronary artery (LAD) reduced coronary blood flow (CBF) in the nonischemic hearts in a dose-dependent manner. Also, in the ischemic state that CBF was decreased to 33% of the baseline, the intracoronary administration of aldosterone (0.1 nmol/L) rapidly decreased CBF (37.4+/-3.8 to 19.3+/-5.2 mL/100 g/min; P<0.05), along with decreases in fractional shortening (FS) (8.4+/-0.7 to 5.4+/-0.4%; P<0.05) and lactate extraction rate (LER) (-31.7+/-2.9 to -41.4+/-3.7%; P<0.05). The decrease in CBF was reproduced by the infusion of bovine serum albumin-conjugated aldosterone. Notably, these aldosterone-induced deteriorations of myocardial contractile and metabolic functions were blunted by the co-administration of GF109203X, an inhibitor of PKC, but not spironolactone. In addition, aldosterone activated vascular PKC. These results indicate that aldosterone nongenomically induces vasoconstriction via PKC-dependent pathways possibly through membrane receptors, which leads to the worsening of the cardiac contractile and metabolic functions in the ischemic hearts. Elevation of plasma or cardiac aldosterone levels may be deleterious to ischemic heart disease through its nongenomic effects.  相似文献   
959.
Background In order to apply fecal pancreatic elastase for follow-up of exocrine pancreatic function in chronic pancreatitis and cystic fibrosis, we examined the sensitivity, specificity, and long-term variability of a new polyclonal antibody-based enzyme-linked immunosorbent assay (ELISA). Methods Patients with definite chronic pancreatitis (n = 23), probable or possible chronic pancreatitis (n = 14), autoimmune pancreatitis (n = 7), or acute pancreatitis (n = 11), and 51 healthy subjects and 11 healthy infants participated in this study. Pancreatic function was graded as normal (n = 3), mild (n = 18), moderate (n = 9), or severe (n = 18) exocrine insufficiency on the basis of secretin tests. Fecal pancreatic elastase was measured by a new ELISA. Results Fecal pancreatic elastase concentration in control subjects varied widely, with a median of 478 μg/g. The specificity of this test was 90.2% with a cutoff value of >200 μg/g. The sensitivities were 60.9% for detecting definite chronic pancreatitis, 76.5% for calcifying pancreatitis, 71.4% for autoimmune pancreatitis, and 7.1% for probable or possible chronic pancreatitis. The sensitivities were 16.7% for mild, 12.5% for moderate, and 72.2% for severe exocrine pancreatic insufficiency. Forty patients were reexamined after a median interval of 347 days. The fecal pancreatic elastase levels between the first and second tests were not significantly different. Two infants, 4.5 and 5 months old, had abnormally low values, but after a median of 304 days all infants showed normal levels (median, 444 μg/g). Conclusions Fecal pancreatic elastase is a reproducible marker for severe exocrine pancreatic insufficiency. This test is valuable for longitudinal follow-up of exocrine pancreatic function.  相似文献   
960.
Background A reduced rectal perceptual threshold has been reported in patients with irritable bowel syndrome (IBS), but this phenomenon may be induced by a comorbid psychological state. We evaluated the rectal pain threshold at baseline and after conditioning (repetitive rectal painful distention: RRD) in patients with IBS or functional abdominal pain syndrome (FAPS), which is an abdominal pain disorder, and in healthy controls, and determined whether rectal hypersensitivity is a reliable marker for IBS. Methods The rectal sensory threshold was assessed by a barostat. First, a ramp distention of 40 ml/min was induced, and the threshold of pain and the maximum tolerable pressure (mmHg) were measured. Next, RRD (phasic distentions of 60-s duration separated by 30-s intervals) was given with a tracking method until the subjects had complained of pain six times. Finally, ramp distention was induced again, and the same parameters were measured. The normal value was defined by calculating the 95% confidence intervals of controls. Results Five or six of the seven IBS patients showed a reduced rectal pain threshold or maximum tolerable pressure, respectively, at baseline. In all patients with IBS, both thresholds were reduced after RRD load, but they were reduced in none of the patients with FAPS. RRD significantly reduced both thresholds in the IBS group (P < 0.05), but it had no effect in the control or FAPS groups. Conclusions Rectal hypersensitivity induced by RRD may be a reliable marker for IBS. Conditioning-induced visceral hypersensitivity may play a pathophysiologic role in IBS.  相似文献   
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