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51.

Background

The purpose of this study was to examine the relationship between magnetic resonance imaging (MRI) and surgical treatment of invasive breast cancer (IBC).

Method

The IBC patients treated from January 2003-June 2008 were reviewed by a single institution.

Results

A total of 814 patients were treated, out of which 562 (69%) underwent breast conservation therapy (BCT), 151 (19%) chose mastectomy alone (M), and 101 (12%) chose mastectomy with reconstruction (M+ R). The mean age was comparatively low in M + R patients (P ≤ 0.001). The mean tumor size was the lowest in BCT patients (P ≤ 0.001). MRI use increased with no significant difference in type of surgery as noted by year. In multivariate analysis, type of surgery was significantly associated with tumor size, multifocality, age, and MRI use. The factors associated with MRI performance were: multifocality, younger age, tumor size, lobular histology, body mass index, and genetic testing.

Conclusions

The use of MRI in IBC patients has increased over the past 5 years, without any observable impact on surgical treatment. Similar factors are associated with mastectomy and MRI performance.  相似文献   
52.

Background

The accuracy of magnetic resonance imaging (MRI) in identifying residual disease after breast conservation therapy (BCT) is unclear.

Method

Review of an institutional database identified patients with positive or close (≤2 mm) margins undergoing MRI before re-excision. Histopathologic correlation was performed.

Results

Forty-three women underwent MRI after BCT. MRI suggested residual disease in 29 patients, of whom 20 (69%) had residual carcinoma pathologically. Nine patients had false-positive MRI as seen by benign pathology findings. Fourteen MRIs indicated no residual disease, of which 6 had residual disease pathologically. The sensitivity and positive predictive value of MRI was 77% and 69%, respectively. MRI conducted within 28 days of the original surgery was 85% sensitive. MRI performed after 28 days was 69% sensitive.

Conclusions

MRI is able to detect residual disease among most patients undergoing re-excision. False-positive results may be caused by inflammatory processes that resemble residual disease.  相似文献   
53.

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   
54.

Background  

Sporadic and sometimes contradictory studies have indicated changes in satellite cell behaviour associated with the progressive nature of human Duchenne muscular dystrophy (DMD). Satellite cell proliferation and number are reportedly altered in DMD and the mdx mouse model. We recently found that satellite cells in MSVski transgenic mice, a muscle hypertrophy model showing progressive muscle degeneration, display a severe ageing-related differentiation defect in vitro. We tested the hypothesis that similar changes contribute to the gradual loss of muscle function with age in mdx and PMP22 mice, a model of human motor and sensory neuropathy type 1A (HMSN1A).  相似文献   
55.
BACKGROUND: There are concerns about adverse vascular effects of intravenous iron by inducing oxidative stress. We therefore examined the effect of a single high dose of intravenous iron on endothelial function and biochemical markers of iron homeostasis. METHODS: In a randomized, placebo-controlled, double-blind, parallel-group study, forearm blood flow (FBF) was assessed by strain-gauge plethysmography in 38 peritoneal dialysis patients before and after a single intravenous infusion of 300 mg iron sucrose. RESULTS: Iron infusion increased total (Delta 601 microg/100 mL, CI 507, 696) and non-transferrin-bound iron (Delta 237.2 micromol/L, CI 173.6, 300.8) approximately 10-fold, as well as redox-active iron nearly five-fold (Delta 0.76 micromol/L, CI 0.54, 0.98). After iron infusion basal FBF was 59% higher than after placebo. FBF response to acetylcholine before and after iron infusion was 263 +/- 32% and 310 +/- 33%, corresponding to 304 +/- 43% and 373 +/- 29% in the placebo group, respectively. Before and after iron or placebo infusion, glyceryl-trinitrate increased resting FBF to 232 +/- 22% and 258 +/- 21% in the iron group, and to 234 +/- 18% and 270 +/- 30% in the placebo group. L-N-monomethyl-arginine decreased FBF to 70 +/- 4% and 72 +/- 3% before and after iron, and to 74 +/- 4% and 73 +/- 4% before and after placebo infusions, respectively. Despite higher basal FBF after iron infusion, absolute and relative FBF changes in response to vasoactive substances were not significantly different between iron and placebo groups. CONCLUSION: Our data suggest that 300 mg intravenous iron sucrose has a vasodilatory effect, but does not impair vascular reactivity in dialysis patients, despite a significant increase in non-transferrin-bound and redox-active iron.  相似文献   
56.
OBJECTIVE: To assess the results of multimodality therapy for patients with recurrent rectal cancer and to analyze factors predictive of curative resection and prognostic for overall survival. SUMMARY BACKGROUND DATA: Locally recurrent rectal cancer is a difficult clinical problem, and radical treatment options with curative intent are not generally accepted. METHODS: A total of 394 patients underwent surgical exploration for recurrent rectal cancer. Ninety were found to have unresectable local or extrapelvic disease and 304 underwent resection of the recurrence. The latter patients were prospectively followed to determine long-term survival and factors influencing survival. RESULTS: Overall 5-year survival was 25%. Curative, negative resection margins were obtained in 45% of patients; in these patients a 5-year survival of 37% was achieved, compared to 16% (P <.001) in patients with either microscopic or gross residual disease. In a logistic regression analysis, initial surgery with end-colostomy and symptomatic pain (both univariate) and increasing number of sites of the recurrent tumor fixation in the pelvis (multivariate) were associated with palliative surgery. Overall survival was significantly decreased for symptomatic pain (P <.001) and more than one fixation (P =.029). Survival following extended resection of adjacent organs was not different from limited resection (28% vs. 21%, P =.11). Patient demographics and factors related to the initial rectal cancer did not affect outcome. Perioperative mortality was only 0.3%, but significant morbidity occurred in 26% of patients, with pelvic abscess being the most common complication. CONCLUSIONS: This study demonstrates that many patients with locally recurrent rectal cancer can be resected with negative margins. Long-term survival can be achieved, especially for patients with no symptoms and minimal fixation of the recurrence in the pelvis, provided no gross residual disease remains.  相似文献   
57.
RATIONALE AND OBJECTIVES: To evaluate the interpretation of computed tomographic pulmonary angiograms performed outside of regular reporting hours, comparing the initial interpretation by the radiology resident to the attending radiologist. MATERIALS AND METHODS: Records for 840 consecutive computed tomographic pulmonary angiograms (CTPA) performed outside of regular reporting hours at two tertiary referral centers from January 1, 2004-December 31, 2005 were reviewed. The preliminary interpretation by the on-call radiology resident was compared to the subsequent final report issued by a subspecialty trained chest radiologist. Studies were stratified as positive, negative, or equivocal for pulmonary embolus. Cases with discordant interpretations or negative CTPA were reviewed to determine impact on clinical outcome. Patients were followed up to 12 months after CTPA to document any subsequent thromboembolic event. RESULTS: Sixteen percent (131/840) of CTPAs were reported positive by the staff radiologist. There was agreement in 90% (752/840) of studies (P = .76, 95% confidence interval, 0.71-0.81) with 86% (114/133) agreement for studies interpreted as positive by residents, 95% (582/612) for studies interpreted as negative by residents, and 63% (60/95) for studies interpreted as equivocal by residents. Studies of optimal quality had higher interobserver agreement than studies of suboptimal quality (P < .0001). In-patient studies were more likely to be positive than emergency room patients (20% vs. 13%) (P = .004). No adverse clinical outcomes were attributed to discordant interpretations. CONCLUSIONS: Radiology residents provide a high level interpretation of on-call CTPA studies, achieving good concordance with the attending radiologists' assessment.  相似文献   
58.
BACKGROUND: Recently, aortic valve stenosis has been demonstrated to exhibit increased expression of certain matrix metalloproteinases (MMPs), and this has relevantly raised the question about possible interdependency between these and their tissue inhibitors. We sought to assess the expression of elastolytic MMPs and their inhibitors (TIMPs) in nonrheumatic aortic stenosis. METHODS: The study comprised 30 stenotic and six noncalcified human aortic valves. To measure the expression levels and the amount and molecular forms of gelatinases (MMP-2, MMP-9) and TIMPs (1, 2), in situ hybridization, gelatin zymography, and reverse zymography were carried out. Antielastin staining by a monoclonal BA-4 antibody was performed to investigate the changes of one of the main substrates of these MMPs, and to substantiate the nature of the putative MMP- synthesizing cell. The cases were also immunostained with an antibody to alpha-smooth muscle actin. Inflammatory cell characterization was managed by monoclonal mouse antibodies (UCHL-1, L26, and PGM-1). RESULTS: Compared with the controls, the calcific valves showed increased mRNA expression and activation of MMP-9, and this was associated with typical characteristics of valve disease. MMP-2 mRNA production was rare, but proMMP-2 protein was detected in all valves. In agreement with the interdependency between MMP-9 and its inhibitors, a suggestive imbalance came out in diseased valves. CONCLUSIONS: The disproportion between MMP-9 and its tissue inhibitors may favor a persistent MMP activation state within the calcific valve and likely contribute to the valvular remodeling process in the setting of developing aortic stenosis.  相似文献   
59.
BACKGROUND: Rat coagulating gland epithelial cells export proteins by an apocrine secretion mode within membrane blebs arising from the apical plasma membrane. Using a pan-PMCA antibody, we have recently shown the plasma membrane Ca(2+)-ATPase (PMCA) being part of the apical plasma membrane of epithelial cells and incorporated into the aposomal membrane. The mRNA of PMCA isoforms 1 and 4 respectively, have been detected by RT-PCR in rat coagulating gland. METHODS: In order to identify which PMCA isoform is integrated into aposomes during apocrine secretion and whether or not PMCA export is influenced by androgens RT-PCR, in situ hybridization, Western blotting, and immunofluorescence experiments were performed. RESULTS: PMCA1b is the isoform which is expressed and located in the apical plasma membrane of coagulating gland epithelial cells and is integrated into the aposomal membrane. In contrast, PMCA4 mRNA and protein are restricted to the stroma. Androgen deprivation by castration within 14 days leads to an accumulation of PMCA1b in coagulating gland epithelium, while aposomes are not detected anymore. CONCLUSIONS: We showed for the first time that PMCA isoform 1b is released via aposomes of the epithelial cells of the rat coagulating gland and that the localization of PMCA1b in the epithelial cells is influenced by androgens.  相似文献   
60.
PURPOSE: A biomechanic study using a cadaver model of a dorsally unstable distal radius fracture was used to compare the stability of percutaneous pinning and volar fixed-angle plating. Among the many surgical options for treating distal radius fractures are percutaneous pinning and internal plate fixation. Although percutaneous pin fixation requires less soft-tissue trauma and has low complication rates, plate fixation allows for early active movement with good clinical results. The biomechanic stability of these 2 methods was studied by using a cadaver model of a dorsally unstable intra-articular distal radius fracture. METHODS: This study was performed on 7 fresh-frozen cadaver arms, in each of which an unstable intra-articular fracture with dorsal comminution was created. The fracture was first fixed with 0.062-mm K-wires inserted in standard crossed fashion and was tested in a pneumatic loading device that indirectly loaded the wrists through the 5 motor tendons 3 times at each level of force in flexion and extension. Testing was then repeated after removal of the pins and fixation with a fixed-angle DVR distal volar radius plate system (Hand Innovations, Inc., Miami, FL). Testing was performed in flexion up to 68 N and in extension up to 100 N, and the distance across the fracture site was measured. RESULTS: Volar plating was significantly more stable than pinning, with an average movement across the fracture site of 2.51 mm for pin fixation and 1.07 mm for plate fixation. The pins also showed a substantial degree of slipping after repeated stressing, but the plates remained stable. CONCLUSIONS: These results show the superior biomechanic stability of internal fixation using plates for dorsally comminuted intra-articular distal radius fractures in this cadaver model. Further clinical correlations are needed.  相似文献   
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