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41.
The vascular responses to acute resistance exercise and resistance exercise training (RET) in overweight women are unclear. Therefore, the purpose of this study was to examine the vasodilatory and wave reflection responses to acute resistance exercise before and after RET. In all, 24 overweight/obese (28.5±0.6?kg?m(-2)) women (44±1 years of age) volunteered for this study. Forearm blood flow (FBF), vasodilatory capacity in response to reactive hyperemia (peak FBF) and wave reflection (radial tonometry) were measured, before and 15?min after five sets of leg press at 10-repetition maximum (RM). Measures of pulse wave reflection included the augmentation index (AIx) and the time of the reflected wave (Tr). Measurements were collected at baseline, after a 4-week control period (before RET) and after 12 weeks of whole-body RET using three sets of five exercises at 50-60% of 1-RM. There were no differences in vascular measurements at baseline or before RET for any variable. Resting FBF (66.7%) and peak FBF (51.6%) increased significantly (P<0.05) after RET compared with before RET. Post-exercise FBF (48.9%) and peak FBF (41.1%) also increased significantly (P<0.05) after RET compared with before RET. Post-exercise AIx decreased significantly (P<0.05), whereas Tr increased significantly (P<0.05) compared with rest at all time points. However, AIx and Tr were unaltered by RET. The 12-week whole-body RET increased the resting and post-exercise FBF as well as vasodilatory capacity without changing wave reflection in premenopausal overweight women. RET may be an important non-pharmacological therapy for reducing cardiovascular risk in overweight and obese premenopausal women. 相似文献
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43.
Catherine E. Cioffi Janet Figueroa Jean A. Welsh 《Journal of the Academy of Nutrition and Dietetics》2018,118(5):886-895.e1
Background
Despite associations of dietary added sugar with excess weight gain and chronic disease risk, intake among most Americans exceeds the recommended limits (<10% total energy). Maternal diet plays an important role in pregnancy-related outcomes, but little is known about the extent of added sugar intake during pregnancy.Objective
To assess intake and identify the top sources of added sugars in the diets of pregnant vs nonpregnant women in the United States.Design
Cross-sectional analysis of data from the National Health and Nutrition Examination Survey (NHANES), 2003-2004 to 2011-2012.Participants
Four thousand one hundred seventy-nine pregnant and nonpregnant women (aged 20 to 39 years) who completed a dietary recall.Statistical analyses performed
Survey-weighted analyses were used to estimate means (95% CIs) in total grams and as percentage of total energy for added sugar intake by pregnancy status and by demographic subgroup and to identify leading sources of added sugar.Results
Added sugar intake trended toward being higher in pregnant compared with nonpregnant women in absolute grams, 85.1 g (95% CI: 77.4 to 92.7) vs 76.7 g (95% CI: 73.6 to 79.9), respectively (P=0.06), but was lower among pregnant women when total energy intake was accounted for, 14.8% (95% CI: 13.8 to 15.7) vs 15.9% (95% CI: 15.2 to 16.6) of total energy, respectively (P=0.03). Among pregnant women, added sugar intake was similar among demographic subgroups. However, in multivariable regression, pregnancy status significantly modified the associations of education and income with added sugar intake, whereby less educated and lower-income women who were pregnant had lower added sugar intakes compared with those who were not pregnant, but more educated or higher-income women did not exhibit this pattern. The top five sources of added sugar for all women were sugar-sweetened beverages; cakes, cookies, and pastries; sugars and sweets; juice drinks and smoothies; and milk-based desserts.Conclusions
Although pregnant women had higher energy intakes, this was not attributed to higher intakes of added sugar. Although education and income affected consumption during pregnancy, intake of added sugar among all women, regardless of pregnancy status, exceeded recommendations. 相似文献44.
Distraction Osteogenesis (DO) has become a treatment alternative to treat severe craniofacial skeletal dysplasias. A rigid external distraction (RED) device has been successfully used to advance the maxilla as well as the maxillary, orbital and forehead complex (monobloc) in children as young as two years, adolescents and adults. This approach has provided predictable and stable results. It can be applied by itself or as an adjunct to traditional orthognathic and craniofacial surgical procedures. The technical aspects, including planning, surgical and orthodontic procedures, required to properly apply the technique are presented. For this severe group of patients the technique has been found to be simpler and safer than traditional surgical methods. Maxillary and midfacial advancement through distraction has been found to be extremely stable in the patients in whom the technique was used. The reasons for stability are discussed as well as the observed morphologic changes in the facial soft tissues, velopharyngeal mechanism and airway. However, challenges remain to be solved to improve all distraction techniques and the need for collaboration between researchers and clinicians is emphasized to maximize the benefits of this already promising and rewarding approach. 相似文献
45.
Hyun Seok Bang Dae Yun Seo Yong Min Chung Kyoung-Mo Oh Jung Jun Park Figueroa Arturo Seung-Hun Jeong Nari Kim Jin Han 《The Korean journal of physiology & pharmacology》2014,18(5):441-446
Ursolic acid (UA), a type of pentacyclic triterpenoid carboxylic acid purified from natural plants, can promote skeletal muscle development. We measured the effect of resistance training (RT) with/without UA on skeletal muscle development and related factors in men. Sixteen healthy male participants (age, 29.37±5.14 years; body mass index=27.13±2.16 kg/m2) were randomly assigned to RT (n=7) or RT with UA (RT+UA, n=9) groups. Both groups completed 8 weeks of intervention consisting of 5 sets of 26 exercises, with 10~15 repetitions at 60~80% of 1 repetition maximum and a 60~90-s rest interval between sets, performed 6 times/week. UA or placebo was orally ingested as 1 capsule 3 times/day for 8 weeks. The following factors were measured pre-and post-intervention: body composition, insulin, insulin-like growth factor-1 (IGF-1), irisin, and skeletal muscle strength. Body fat percentage was significantly decreased (p<0.001) in the RT+UA group, despite body weight, body mass index, lean body mass, glucose, and insulin levels remaining unchanged. IGF-1 and irisin were significantly increased compared with baseline levels in the RT+UA group (p<0.05). Maximal right and left extension (p<0.01), right flexion (p<0.05), and left flexion (p<0.001) were significantly increased compared with baseline levels in the RT+UA group. These findings suggest that UA-induced elevation of serum irisin may be useful as an agent for the enhancement of skeletal muscle strength during RT. 相似文献
46.
Alejandro Nieponice Adolfo E. Badaloni Blair A. Jobe Toshitaka Hoppo Carlos Pellegrini Vic Velanovich Gary W. Falk Kevin Reavis Lee Swanstrom Virender K. Sharma Fabio Nachman Franco F. Ciotola Luis E. Caro Cecilio Cerisoli Demetrio Cavadas Luis Durand Figueroa Daniel Pirchi Michael Gibson Santiago Elizalde Henry Cohen 《World journal of surgery》2014,38(1):96-105
Background
Treatment of esophageal adenocarcinoma often involves surgical resection. Newer technologies in interventional endoscopy have led to a substantial paradigm shift in the management of early-stage neoplasia in Barrett’s esophagus comprising high-grade dysplasia (HGD), intramucosal carcinoma, and, in some cases, submucosal carcinoma. However, there has been no consensus regarding the indications for esophageal preservation in these cases. In this work, consensus guidelines were established for the management of early-stage esophageal neoplasia considering clinically relevant aspects (age, comorbidities, and social environment) in each scenario.Methods
Seventeen experts were invited to participate based on their background and clinical expertise at high-volume centers. A questionnaire was created that included four clinical scenarios covering a wide range of situations within HGD and/or early esophageal neoplasia, particularly where controversies are likely to exist. Each of the clinical scenarios was open to discussion subdivided by patient age (20, 50, and 80 s). For each clinical scenario an expert was chosen to defend that position. Each defense triggered a subsequent discussion during a consensus meeting. Conclusions of that discussion together with an accompanying literature analysis allowed experts to confirm or change their original choices and served as the basis for the recommendations stated in this article.Results
There was 100 % consensus supporting esophageal preservation in patients with HGD, independent of patient age or Barrett’s length. In patients with T1a adenocarcinoma, consensus for preservation was not reached (65 %) for young and middle-aged individuals but was supported for elderly patients (100 %). For T1b adenocarcinoma, consensus was reached for surgical resection (90 %), leaving organ preservation for patients with very low risk of nodal invasion or poor surgical candidates.Conclusion
Advances in endoscopic imaging and therapy allow for organ preservation in most settings of early-stage neoplasia of the esophagus, provided that the patient understands the implications of this decision. 相似文献47.
The cytoskeleton in Chediak-Higashi syndrome fibroblasts 总被引:2,自引:0,他引:2
The Chediak-Higashi syndrome (CHS) trait is expressed in cultured human skin fibroblasts as an abnormal perinuclear concentration of moderately enlarged lysosomes. The cytoskeleton of CHS fibroblasts appears intact. Microtubules are normal in number and morphology, as assessed by colchicine binding studies, antitubulin immunofluorescence, and electron microscopy. Deformability by shear force is unaltered and microfilaments are abundant. However, CHS lysosomes appear to interact abnormally with the cytoskeleton, since the perinculear aggregation partially disperses after depolymerization of cell microtubules with colchicine. These results suggest that CHS is associated with a defect of either the lysosomal membrane itself or of lysosomal membrane- microtubule interaction. 相似文献
48.
The contribution of von Willebrand factor (vWF)-platelet binding to platelet-collagen interaction was examined in vitro. The binding of vWF to platelets was mediated and regulated by ristocetin. Subthreshold concentrations of ristocetin (less than or equal to 1 mg/mL), insufficient to cause ristocetin-induced platelet aggregation (RIPA), were added to platelet-rich plasma (PRP) prior to the addition of collagen. The collagen-induced platelet aggregation (CIPA) was modified by ristocetin and the degree of alteration was dependent on the ristocetin concentration. Response as a function of ristocetin concentration was designated the Collagen-Platelet Aggregation Response (CoI-PAR). In normal PRP the CoI-PAR was a progressive inhibition followed by decreasing inhibition and then an enhanced response. The enhanced response occurred over a narrow range of ristocetin concentrations (0.8 to 1.0 mg/mL). In the absence of vWF (severe von Willebrand's disease, Type I, vWF less than 1%) the CoI-PAR was a progressive, eventually complete inhibition with no enhanced response (with ristocetin concentrations up to 3.0 mg/mL). With addition of vWF to this PRP an enhanced response was observed at a ristocetin concentration inversely proportional to the vWF level. PRP from a patient with severe Hemophilia A showed a response within the normal range. Subthreshold ristocetin did not cause plasma protein precipitation or platelet release of 3H-serotonin, nor induce micro platelet aggregate formation. Digestion of platelet membrane glycoproteins (GP(s] with chymotrypsin demonstrated that upon removal of GPI, RIPA was absent, CIPA retained and the CoI-PAR was progressive inhibition, with no enhancement. With removal of GPs I, II, and III, RIPA, CIPA, and the CoI-PAR were absent. A dose-response 125I-vWF- platelet binding occurred with increasing ristocetin concentrations which was unchanged by the addition of collagen. These results demonstrated that ristocetin-platelet association inhibited CIPA, and vWF-platelet binding enhanced platelet-collagen adhesion and platelet aggregation. The in vitro-enhanced CIPA represents a vWF-dependent aggregation of sufficient magnitude to overcome the inhibitory effect of ristocetin. These studies demonstrate an influential interaction of ristocetin, vWF, and collagen with the platelet membrane and imply an important hemostatic contribution of vWF-platelet binding in platelet- collagen interaction. 相似文献
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50.