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91.
There have been few studies examining the short-term effect of high-impact activities on bone metabolism measured by bone serum marker concentrations. The purpose of this study was to examine the effect of short-term high-impact jump activity on bone turnover in female college-aged non-athletes. Twenty six healthy females were randomly assigned to a control or jump group. The subjects jumped 5 days per week for 2 weeks. The participants completed 10 jumps per session. A general health questionnaire and a bone-specific physical activity assessment instrument (BPAQ) were completed. BPAQ scores were calculated based on the past history of exercise. Blood draws were taken in both groups before and after the two-week experimental period. The vertical ground reaction force (VGRF) of all jumps and jump height were measured for each subject daily and the osteogenic index (OI) was measured. Concentrations of serum osteocalcin (OC), Bone Specific Alkaline Phosphatase (BAP), C-Terminal Telopeptides of Type I Collagen (CTX) and plasma Tartrate-Resistant Acid Phosphatase (TRAP5b) were assessed pre and post jump protocol to measure bone formation and resoprtion respectively. A significant interaction (time x group) was found in TRAP5b, and BAP values (p < 0.05). There was a significant decrease in CTX and BAP values in the jump group (p < 0.05) after the two week jump protocol. No significant interactions or changes were observed in OC values for either the jump or the control group. Two weeks of jump activity consisting of 10 jumps/day for 5 days/week with a weekly osteogenic index of 52.6 significantly decreased markers of bone resorption (TRAP5b and CTX) and bone formation (BAP) in young female non-athletes.

Key points

  • Please provide 3-5 bullet points of the study.
  • Inductive qualitative methodologies can encourage the much-needed voice of female youth in sport and physical activity research.
  • Vignettes serve, not only as a method to illustrate data, but also as a medium to teach contextually relevant information to participants and sport science service providers.
  • The barriers and solutions to female youth engagement in physical activity are best understood through the perspectives of the intended participant.
  • Female youth can serve as central informants in the development and analysis of research projects relating to female youth physical activity.
Key words: Jump exercise, vertical ground reaction force, bone serum markers, randomized controlled study  相似文献   
92.
Chronic allograft nephropathy (CAN) of renal allografts is still the most important cause of graft loss. A subset of these patients have transplant glomerulopathy (TGP), characterized by glomerular basement membrane (GBM) duplications, but of unknown etiology. Recently, a role for the immune system in the pathogenesis of TGP has been suggested. In 11 of 16 patients with TGP and in 3 of 16 controls with CAN in the absence of TGP we demonstrate circulating antibodies reactive with GBM isolates. The presence of anti-GBM antibodies was associated with the number of rejection episodes prior to diagnosis of TGP. Sera from the TGP patients also reacted with highly purified GBM heparan sulphate proteoglycans (HSPG). Indirect immunofluorescence with patient IgG showed a GBM-like staining pattern and colocalization with the HSPGs perlecan and especially agrin. Using patient IgG, we affinity purified the antigen and identified it as agrin. Reactivity with agrin was found in 7 of 16 (44%) of patients with TGP and in 7 of 11 (64%) patients with anti-GBM reactivity. In conclusion, we have identified a humoral response against the GBM-HSPG agrin in patients with TGP, which may play a role in the pathogenesis of TGP.  相似文献   
93.
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95.
IgA nephropathy (IgAN), the most common primary glomerulonephritis in the world, is characterized by IgA immune complex-mediated mesangial cell proliferation. The transferrin receptor (TfR) was identified previously as an IgA1 receptor, and it was found that, in biopsies of patients with IgAN, TfR is overexpressed and co-localizes with IgA1 mesangial deposits. Here, it is shown that purified polymeric IgA1 (pIgA1) is a major inducer of TfR expression (three- to four-fold increase) in quiescent human mesangial cells (HMC). IgA-induced but not cytokine-induced HMC proliferation is dependent on TfR engagement as it is inhibited by both TfR1 and TfR2 ectodomains as well as by the anti-TfR mAb A24. It is dependent on the continued presence of IgA1 rather than on soluble factors released during IgA1-mediated activation. In addition, pIgA1-induced IL-6 and TGF-beta production from HMC was specifically inhibited by mAb A24, confirming that pIgA1 triggers a TfR-dependent HMC activation. Finally, upregulation of TfR expression induced by sera from patients with IgAN but not from healthy individuals was dependent on IgA. It is proposed that deposited pIgA1 or IgA1 immune complexes could initiate a process of auto-amplification involving hyperexpression of TfR, allowing increased IgA1 mesangial deposition. Altogether, these data unveil a functional cooperation between pIgA1 and TfR for IgA1 deposition and HMC proliferation and activation, features that are commonly implicated in the chronicity of mesangial injuries observed in IgAN and that could explain the recurrence of IgA1 deposits in the mesangium after renal transplantation.  相似文献   
96.

Background

Non-alcoholic fatty liver disease (NAFLD) is a common, severe disease in obese patients. However, NAFLD is usually underestimated by ultrasonography. Liver biopsy is not routinely done in bariatric surgery or during the follow-up. This study therefore examined the correlation between metabolic syndrome and NAFLD in morbidly obese patients based on an assessment using transient hepatic elastography (THE).

Material and Methods

This study involved 50 female patients in the pre-operative phase for bariatric surgery. Before surgery, we collected clinical, laboratory, and anthropometric variables. THE measurements were obtained using a FibroScan® device (Echosens, Paris, France), and steatosis was quantified using Controlled Attenuation Parameter software (CAP). Statistical analyses were done using linear correlation and the Kruskal-Wallis test.

Results

The mean of THE and CAP values were 7.56?±?4.78 kPa and 279.94?±?45.69 dB/m, respectively, and there was a significant linear correlation between the two measurements (r?=?0.651; p?<?0.001). The numbers of metabolic syndrome parameters did not influence the THE (p?=?0.436) or CAP (p?=?0.422) values. HbA1c and HOMA-IR showed a strong linear correlation with CAP (r?=?0.643, p?=?0.013 and r?=?0.668, p?=?0.009, respectively) and a tendency to some linear correlation with THE (r?=?0.500, p?=?0.05 and r?=?0.500, p?=?0.002, respectively).

Conclusion

Morbidly obese women submitted to FibroScan® presented a high prevalence of severe steatosis and advanced fibrosis in our sample. Insulin resistance parameters were correlated with steatosis, but less with fibrosis.
  相似文献   
97.

Background

Limited prospective data on the anatomic and functional outcome after laparoscopic sacrocolpopexy (LSC) are available in the literature.

Objective

To describe the medium-term anatomic and functional outcome of LSC.

Design, setting, and participants

Prospective consecutive series of 132 women with vaginal vault prolapse undergoing LSC between 2001 and 2006, which was after our learning curve. Patients with urodynamically proven stress incontinence (SI) underwent a concomitant tension-free vaginal tape (TVT) procedure.

Intervention

Patients underwent LSC with a polypropylene implant.

Measurements

Principal outcome measures were anatomic cure (stage 1 or lower) assessed by the Pelvic Organ Prolapse Quantification (POPQ) system and subjective cure and impact on quality of life measured by a standardised interview and, since its introduction in 2004, by a prolapse-specific quality-of-life questionnaire (P-QOL).

Results and limitations

At a mean follow-up of 12.5 mo, the anatomic cure rate for the apex was 98%. Anatomic failures elsewhere were mainly at the posterior compartment (18%). Subjective prolapse cure rate was 91.7%, and no patients required reoperation for recurrent prolapse. Symptoms of preoperative SI, urge incontinence, or constipation were cured in 43%, 46%, and 42% of patients, respectively. The rate of de novo SI was 7.3%. De novo constipation developed in 5% and de novo dyspareunia developed in 19%. Patients’ quality of life improved significantly. Erosions occurred in 4.5%, all within 1 yr. A limitation of the study is that the quality-of-life assessment score became available halfway through the study, limiting the number of preoperative observations (n = 36).

Conclusions

We demonstrated that LSC results in good anatomic outcome and subjective cure of prolapse symptoms at medium term. The posterior compartment was most vulnerable for recurrence.  相似文献   
98.
The high specificity of blood coagulation proteases has been attributed not only to residues surrounding the active site but also to other surface domains that are involved in recognizing and interacting with macromolecular substrates and inhibitors. Specific blood coagulation inhibitors obtained from exogenous sources such as blood sucking salivary glands and snake venoms have been identified. Some of these inhibitors interact with exosites on coagulation enzymes. Two examples are discussed in this short revision. Bothrojaracin is a snake venom-derived protein that binds to thrombin exosites 1 and 2. Complex formation impairs several exosite-dependent activities of thrombin including fibrinogen cleavage and platelet activation. Bothrojaracin also interacts with proexosite 1 on prothrombin thus decreasing the zymogen activation by the prothrombinase complex (FXa/FVa). Ixolaris is a two Kunitz tick salivary gland inhibitor, that is homologous to tissue factor pathway inhibitor. Recently it was demonstrated that ixolaris binds to heparin-binding exosite of FXa, thus impairing the recognition of prothrombin by the enzyme. In addition, ixolaris interacts with FX possibly through the heparin-binding proexosite. Differently from FX, the ixolaris-FX complex is not recognized as substrate by the intrinsic tenase complex (FIXa/FVIIIa). We conclude that these inhibitors may serve as tools for the study of coagulation exosites as well as prototypes for new anticoagulant drugs.  相似文献   
99.

Purpose

While infraorbital nerve blocks have demonstrated analgesic benefits for pediatric nasal and facial plastic surgery, no studies to date have explored the effect of this regional anesthetic technique on adult postoperative recovery. We designed this study to test the hypothesis that infraorbital nerve blocks combined with a standardized general anesthetic decrease the duration of recovery following outpatient nasal surgery.

Methods

At a tertiary care university hospital, healthy adult subjects scheduled for outpatient nasal surgery were randomly assigned to receive bilateral infraorbital injections with either 0.5% bupivacaine (Group IOB) or normal saline (Group NS) using an intraoral technique immediately following induction of general anesthesia. All subjects underwent a standardized general anesthetic regimen and were transported to the recovery room following tracheal extubation. The primary outcome was the duration of recovery (minutes) from recovery room admission until actual discharge to home. Secondary outcomes included average and worst pain scores, nausea and vomiting, and supplemental opioid requirements.

Results

Forty patients were enrolled. A statistically significant difference in mean [SD] recovery room duration was not observed between Groups IOB and NS (131 [61] min vs 133 [58] min, respectively; P = 0.77). Subjects in Group IOB did experience a reduction in average pain on a 0–100 mm scale (mean [95% confidence interval]) compared to Group NS (?11 [?21 to 0], P = 0.047), but no other comparison of secondary outcomes was statistically significant.

Conclusions

When added to a standardized general anesthetic, bilateral IOB do not decrease actual time to discharge following outpatient nasal surgery despite a beneficial effect on postoperative pain.  相似文献   
100.

Purpose

The authors sought to determine magnetic resonance/magnetic resonance cholangiopancreatography (MR/MRCP) imaging features of incidentally discovered benign, noncommunicating cystic neoplasms (BNCNs) of the pancreas to assess their evolution over time and identify MR/MRCP imaging features predictive of tumour growth.

Material and methods

This was a retrospective study, so informed consent was waived. Sixty-two patients with a diagnosis of BNCN were assessed. Inclusion criteria were incidentally discovered cystic neoplasm of the pancreas with nonmeasurable walls, no mural nodules and no communication with the pancreatic ductal system and who underwent ≥1 MR/MRCP examination. Image analysis, performed at diagnosis and during follow-up, included macroscopic pattern (microcystic/macrocystic/mixed), number of cysts (unicystic/oligocystic/multicystic), BNCN maximum diameter and tumour growth rates.

Results

A total of 64 BNCNs was detected. Macroscopic pattern was mixed in 31/64 (48%), microcystic in 28/64 (44%) and macrocystic in 5/64 (8%). BNCNs appeared multicystic in 38/64 (59%) cases, oligocystic in 22/64 (35%) and unicystic in 4/64(6%). All qualitative parameters remained unchanged during follow-up. At diagnosis, the median maximum BNCN diameter was 35.0 mm and 38.0 mm at the final examination (p<0.001). BNCNs showed a tumour growth rate of 2 mm/year.

Conclusions

Mixed and microcystic patterns were the most common, accounting for 48% and 44% of cases, respectively, and showed no change over time. MR/MRCP features predictive of lesion enlargement were a mixed/ macrocystic pattern, and lesion size was >3 cm (both p<0.001).  相似文献   
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