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61.
Chronic stress and depression have adverse consequences on many organ systems, including the skeleton, but the mechanisms underlying stress‐induced bone loss remain unclear. Here we demonstrate that neuropeptide Y (NPY), centrally and peripherally, plays a critical role in protecting against stress‐induced bone loss. Mice lacking the anxiolytic factor NPY exhibit more anxious behavior and elevated corticosterone levels. Additionally, following a 6‐week restraint, or cold‐stress protocol, Npy‐null mice exhibit three‐fold greater bone loss compared to wild‐type mice, owing to suppression of osteoblast activity. This stress‐protective NPY pathway acts specifically through Y2 receptors. Centrally, Y2 receptors suppress corticotropin‐releasing factor expression and inhibit activation of noradrenergic neurons in the paraventricular nucleus. In the periphery, they act to control noradrenaline release from sympathetic neurons. Specific deletion of arcuate Y2 receptors recapitulates the Npy‐null stress response, coincident with elevated serum noradrenaline. Importantly, specific reintroduction of NPY solely in noradrenergic neurons of otherwise Npy‐null mice blocks the increase in circulating noradrenaline and the stress‐induced bone loss. Thus, NPY protects against excessive stress‐induced bone loss, through Y2 receptor‐mediated modulation of central and peripheral noradrenergic neurons. © 2014 American Society for Bone and Mineral Research.  相似文献   
62.

Introduction

Despite inguinal hernia repair being one of the most common elective operations performed in general surgical practice, there are many controversies including indications for repair and selection of the surgical technique. In recent years, laparoscopic repair has gained wider acceptance because it is associated with fewer postoperative complications and less chronic pain when compared with conventional approaches with similar recurrence rate. However, patients with lower abdominal surgery are contraindicated for laparoscopic approach. There are few studies that evaluated whether patients who have been subjected to radical prostatectomy might be subjected to laparoscopic hernia repair with the same benefits as those without previous radical prostatectomy.

Methods

Between March 2010 and March 2013, 20 consecutive patients, who had been subjected to prior radical prostatectomy, underwent laparoscopic transabdominal inguinal repair and were followed prospectively. Surgical procedure was performed using a standard technique.

Results

Mean operative time was 67.5 min. There was only one (5 %) intraoperative minor complication, an injury to the inferior epigastric vessels, which was managed by clipping of the vessels. There were no major postoperative complications. After 24 h and on the seventh postoperative day, 85 and 90 % of patients had no pain or only complained of discomfort, respectively. Nine patients (45 %) did not need any analgesics postoperatively. The mean time to return to leisure activities and to work was 3.1 and 5.6 days, respectively. There was no conversion to open surgery. All patients were discharged within 24 h. After a mean follow-up of 14 months, none of the patients presented recurrence.

Conclusion

TAPP after prostatectomy is safe and effective. It seems that patients undergoing laparoscopic repair after radical prostatic resection have the same benefits as those without prostatectomy.  相似文献   
63.
The surface smoothness of composite restorations affects not only their esthetic appearance but also other properties. Thus, rough surfaces can lead to staining, plaque accumulation, gingival irritation, recurrent caries, abrasiveness, wear kinetics, and tactile perception by the patient. The aim of this study was to evaluate the influence of irrigation during the finishing and polishing of composite resin restorations. A systematic search of the PubMed, Cochrane Library, EMBASE, Web of Science, and Clinical Trials databases was conducted. Papers published up to 11 February 2021 were considered. The quality of each study was assessed using the modified Consolidated Standards of Reporting Trials checklist for reporting in vitro studies on dental materials. No clinical studies were identified. Six in vitro studies were included, reporting changes in physical and esthetic properties. After performing a methodological quality assessment of the studies, some limitations were identified, the main limitation being the heterogeneous methodology across studies. The evidence resulting from this systematic review did not favor either wet or dry finishing/polishing procedures. There is a clear need for well-designed studies focusing on the comparison of dry/wet finishing/polishing with standard protocols to evaluate the differences among different materials and methods.  相似文献   
64.
Objective The objective was to determine the presence and frequency of micrometastasis in lymph nodes of patients with rectal cancer treated by preoperative chemoradiation followed by curative resection.Patients and methods All 56 patients included were treated with 5-FU and leucovorin plus 5,040 cGy, followed by radical surgery and were diagnosed with stage II distal rectal adenocarcinoma after complete pathological examination (ypT3-4N0M0). Immunohistochemistry was assessed with cytokeratin monoclonal antibody AE1/AE3. Three 4-m paraffin sections were obtained from each lymph node, cut at 50 m apart from each other. The results were reviewed by two independent pathologists.Results Mean number of lymph nodes was 9.6 per patient. Four patients (7%) and seven lymph nodes (1.35%) were positive for micrometastasis. Three patients had pT3 and one a pT4 tumor. One of the patients had positive micrometastasis and the presence of mucinous deposits. One other patient had mucinous deposits without any micrometastasis. All four patients are alive with no evidence of recurrent disease. Fourteen patients negative for micrometastasis had recurrent disease (25%), eight systemic (14.7%) and six locoregional (10.3%). There were two cancer-related deaths. The mean follow-up period was 39 months.Conclusion Patients with rectal cancer treated by preoperative chemoradiation showed a surprisingly low rate of micrometastasis detection (7%), even in high-risk patients (T3 and T4 tumors). Lymph node micrometastasis was not associated with decreased overall or disease-free survival. The identification of mucinous deposits on lymph nodes with no viable tumor cells may be direct evidence of lymph node downstaging. The downstaging effect of preoperative chemoradiation therapy may be significant in reducing even micrometastasis detection in low rectal cancer managed by this treatment strategy.  相似文献   
65.
Protease-activated receptor 2 (PAR2) is the second member of a new subfamily of G-protein coupled receptors: the protease-activated receptors (PARs). At present, four different PARs have been cloned and all of them share the same basic mechanism of activation. A serine protease cleaves the extended, extracellular N-terminus of the receptor at a specific site within the protein chain to expose an N-terminal tethered ligand domain, which binds to and activates the cleaved receptor. In this manner, trypsin and mast cell beta-tryptase activate PAR2. PARs are single use receptors because proteolytic activation is irreversible and the cleaved receptors are degraded in lysosomes. Thus, PARs play important roles in emergency situations, such as trauma and inflammation. Emerging evidence indicates that PAR2 is involved in the cardiovascular, pulmonary and gastrointestinal systems, where it controls inflammation and nociception. Work with selective agonists and knockout animals suggests a contribution of PAR2 to certain inflammatory diseases. Therefore, selective antagonists or agonists of these receptors may be useful therapeutic agents for the treatment of human diseases.  相似文献   
66.
The brown algal genus Laminaria (Phaeophyceae, Laminariales) is ecologically and economically important. Laminaria ochroleuca is the genus member with the southernmost distribution in the Northern hemisphere, from Southern Great Britain to Morocco. Here we describe the characterization of 15 microsatellite loci that can be used to study genetic diversity at different spatial scales and its dynamics in declining southern populations. These loci identified a number of alleles ranging from 3 to 26 (mean = 9). Expected heterozygosities range from 0.0824 to 0.9401. We also tested cross-amplification of these microsatellite markers in two other species within the genus, L. hyperborea and L. digitata. A total of eight and ten alleles cross-amplified in L. hyperborea and L. digitata, respectively. These 15 variable microsatellite loci are an important molecular tool to conduct population genetics studies in L. ochroleuca and other species within the genus.  相似文献   
67.

Background

Remote ischemic perconditioning (rPER) is the newest technique described to mitigate ischemia and reperfusion (IR) injury. Local postconditioning (POS) is also an effective technique for this purpose. It is uncertain if adding local POS to rPER provides superior liver protection, so we tested this hypothesis.

Materials and methods

Twenty five Wistar rats were assigned into five groups: sham, IR, POS, rPER, and rPER + POS. Animals were subjected to liver ischemia for 60 min. POS consisted of four cycles of 5-min liver perfusion followed by 5-min liver ischemia (40 min total) after the major ischemic period. rPER consisted of four cycles of 5-min hindlimb ischemia followed by 5 min hindlimb perfusion contemporaneously to major liver ischemic period, during its last 40 min. After 2 h, median and left lobes were harvested for malondialdehyde and Trolox equivalent antioxidant capacity (TEAC) measurement, and blood for the measurement of serum transaminases.

Results

All tissue conditioning techniques were able to reduce transaminases serum levels, having no differences among them. All tissue conditioning techniques were able to reduce hepatic tissue MDA level; however, only rPER + POS had higher values than SHAM. All tissue conditioning techniques also enhanced TEAC; however, only POS had lower TEAC than SHAM.

Conclusions

rPER appears as the most promising technique to avoid IR injury. This technique reduced oxidative stress of cell membranes and lowered transaminases serum level. There was no additive protection when POS and rPER were held together.  相似文献   
68.
The aim of this study was to conduct a systematic review of studies that verified the effects of physical exercise on vascular endothelial growth factor (VEGF) in elderly.  相似文献   
69.
The purpose of this study was to verify the efficacy of a Perceptual-Motor Competences Training Program upon the performance on UFOV of an experimental active group of elderly drivers. Program tasks were conceived to force subjects to divide their attention for central and peripheral stimuli, using a visual strategy of gazing at an anchor-point and, from there, detect important clues on peripheral visual field. For this purpose, almost all tasks were performed on groups of two, being one responsible for testing the other and switching functions from time to time (for instance, dropping one of two juggling handkerchiefs hold apart, one in each tester hand, with the partner having to detect which was dropped and react as quick as possible, catching it before it felt to the floor). We found a significant improvement in the capacity of dividing attention for central and peripheral stimuli under a visual environment full of distractors (selective attention UFOV test) following the Program, as well as a significant reduction on the category of risk (component based upon the three UFOV subtests results), which evidence very clearly the benefits of this training program on the elderly experimental group and its potential to reduce their risk of being involved in car accidents, on their fault, due to perceptual reasons.  相似文献   
70.
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