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141.

Background/Purpose

Surgical treatment of long-gap esophageal atresia (LGEA) is challenging. Methods which facilitate stretching of the esophageal pouches may allow primary anastomosis. Botulinum toxin type A (BTX-A) blocks acetylcholine release in neuromuscular junctions, thereby causing muscle relaxation. We hypothesized that intramural injections with BTX-A into the esophageal wall of piglets would significantly elongate the tissue upon stretch.

Methods

Twenty-four piglets were randomized to receive BTX-A of placebo (saline). After one hour, the esophagus was removed en bloc and tested in a stretch-tension device.

Results

The mean esophageal elongation was 84% (range 83–101) in the BTX-A-group and 65% (50–78) in the control group. The mean difference between the two groups was 18%, which was significant (p < 0.001).

Conclusion

Intramural injections with botulinum toxin type A elongate the esophagus significantly. Clinically, this could be a potential method to achieve primary anastomosis in LGEA. Additional clinical studies are necessary to evaluate the method before it can be generally recommended.  相似文献   
142.
Little information exists regarding the efficacy, modifiers, and outcomes of anemia management in children with CKD or ESRD. We assessed practices, effectors, and outcomes of anemia management in 1394 pediatric patients undergoing peritoneal dialysis (PD) who were prospectively followed in 30 countries. We noted that 25% of patients had hemoglobin levels below target (<10 g/dl or <9.5 g/dl in children older or younger than 2 years, respectively), with significant regional variation; levels were highest in North America and Europe and lowest in Asia and Turkey. Low hemoglobin levels were associated with low urine output, low serum albumin, high parathyroid hormone, high ferritin, and the use of bioincompatible PD fluid. Erythropoiesis-stimulating agents (ESAs) were prescribed to 92% of patients, and neither the type of ESA nor the dosing interval appeared to affect efficacy. The weekly ESA dose inversely correlated with age when scaled to weight but did not correlate with age when normalized to body surface area. ESA sensitivity was positively associated with residual diuresis and serum albumin and inversely associated with serum parathyroid hormone and ferritin. The prevalence of hypertension and left ventricular hypertrophy increased with the degree of anemia. Patient survival was positively associated with achieved hemoglobin and serum albumin and was inversely associated with ESA dose. In conclusion, control of anemia in children receiving long-term PD varies by region. ESA requirements are independent of age when dose is scaled to body surface area, and ESA resistance is associated with inflammation, fluid retention, and hyperparathyroidism. Anemia and high ESA dose requirements independently predict mortality.Almost three decades after the advent of recombinant erythropoietin, the management of renal anemia has become a recent focus of attention and changing paradigms. Whereas correction of hemoglobin (Hb) levels to near-normal has previously been recommended on the basis of association studies linking more severe anemia to morbidity and mortality with dialysis,13 interventional clinical trials consistently demonstrate that near-normalization of Hb increases the risk of vascular events and mortality in adults receiving maintenance hemodialysis and in those with CKD who are not undergoing dialysis.46 This has prompted ongoing reevaluation and revisions of treatment targets in patients exposed to erythropoiesis-stimulating agents (ESAs).7The appropriateness of applying treatment recommendations established in adult hemodialysis populations at high cardiovascular risk and adults with CKD to children undergoing dialysis is questionable because cardiovascular events are far less common in children with CKD. Furthermore, two thirds of children requiring dialysis initially opt for peritoneal dialysis (PD), and there are no systematic studies in the adult PD population to inform the optimal Hb target range in these patients. The risk profile of patients receiving PD may differ from that of the hemodialysis setting because of the absence of dialysis-induced intermittent hemoconcentration and lack of contact activation of the complement and coagulation systems.Further aspects to consider in pediatric anemia management are the greater physical activity of children and the need for optimal cognitive functioning at school.8,9 The significant physiologic variation of the normal Hb range with age10 and the relative ESA sensitivity that reportedly increases with age during early childhood are also noteworthy.11The registry of the International Pediatric Peritoneal Dialysis Network (IPPN) prospectively collects detailed clinical, biochemical, dialysis, and medication-related information (including ESA types and doses and modalities of iron supplementation) from a substantial number of children undergoing long-term PD around the world. In-depth analysis of this unique database has allowed us to (1) gain insight into the demographic characteristics of renal anemia and its treatment in the pediatric PD population worldwide, (2) explore the relationship between ESA dose requirements and body dimensions, (3) identify factors contributing to ESA resistance in children, and (4) associate anemia control with patient outcomes.  相似文献   
143.
Hypoparathyroidism (hypoPT) is characterized by a state of low bone turnover and high bone mineral density (BMD) despite conventional treatment with calcium supplements and active vitamin D analogues. To assess effects of PTH substitution therapy on 3‐dimensional bone structure, we randomized 62 patients with hypoPT into 24 weeks of treatment with either PTH(1‐84) 100 µg/day subcutaneously or similar placebo as an add‐on therapy. Micro‐computed tomography was performed on 44 iliac crest bone biopsies (23 on PTH treatment) obtained after 24 weeks of treatment. Compared with placebo, PTH caused a 27% lower trabecular thickness (p < 0.01) and 4% lower trabecular bone tissue density (p < 0.01), whereas connectivity density was 34% higher (p < 0.05). Trabecular tunneling was evident in 11 (48%) of the biopsies from the PTH group. Patients with tunneling had significantly higher levels of biochemical markers of bone resorption and formation. At cortical bone, number of Haversian canals per area was 139% higher (p = 0.01) in the PTH group, causing a tendency toward an increased cortical porosity (p = 0.09). At different subregions of the hip, areal BMD (aBMD) and volumetric BMD (vBMD), as assessed by dual‐energy X‐ray absorptiometry (DXA) and quantitative computed tomography (QCT), decreased significantly by 1% to 4% in the PTH group. However, at the lumbar spine, aBMD decreased by 1.8% (p < 0.05), whereas vBMD increased by 12.8% (p = 0.02) in the PTH compared with the placebo group. © 2012 American Society for Bone and Mineral Research.  相似文献   
144.
Several studies evaluating the clinical effectiveness of endocrine therapy alone in breast cancer patients aged 70 years or older reported comparable survival rates to conventional surgical therapy, although the incidence of local recurrences was higher. Primary endocrine therapy is therefore only recommended as an alternative approach in elderly woman with estrogen receptor positive tumors who are deemed inoperable or who refuse surgery. We report our experience with aromatase inhibitors as primary endocrine therapy for estrogen receptor positive breast cancer in postmenopausal woman who are impaired by other diseases, refuse surgery or are of old age. Fifty-six patients with fifty-seven ER+ operable breast cancers who refused surgery, were judged ineligible for surgery because of comorbidity, or were of old age were treated with endocrine therapy using aromatase inhibitors only. Digital mammography and high-end breast ultrasound were used to assess tumor sizes. The mean age of the patients was 74 years (range 52-102 years). All patients suffered from breast cancer. The mean follow-up interval was 40 months (range 5-92 months). Seven patients (12%) achieved complete clinical remission, 31 (57%) partial response giving an overall objective response rate of 69%. In addition, seven (12%) patients showed stable disease, giving a clinical benefit rate (complete remission + partial response + stable disease rate) of 81%. Eleven patients (19%) progressed after an initial partial response or stable disease. Only one patient (2%) progressed on endocrine therapy within the first months. Eventually, 22 (39%) patients underwent surgery after informed consent to achieve better local tumor control. Primary endocrine therapy with aromatase inhibitors may offer an effective and safe alternative to surgery giving a high local control rate in postmenopausal women who refuse surgery, who are judged ineligible for surgery, or are of old age.  相似文献   
145.
FRAX is a tool that identifies individuals with high fracture risk who will benefit from pharmacological treatment of osteoporosis. However, a majority of fractures among elderly occur in people without osteoporosis and most occur after a fall. Our aim was to accurately identify men with a high future risk of fracture, independent of cause. In the population‐based Uppsala Longitudinal Study of Adult Men (ULSAM) and using survival analysis we studied different models' prognostic values (R2) for any fracture and hip fracture within 10 years from age 50 (n = 2322), 60 (n = 1852), 71 (n = 1221), and 82 (n = 526) years. During the total follow‐up period from age 50 years, 897 fractures occurred in 585 individuals. Of these, 281 were hip fractures occurring in 189 individuals. The rates of any fracture were 5.7/1000 person‐years at risk from age 50 years and 25.9/1000 person‐years at risk from age 82 years. Corresponding hip fractures rates were 2.9 and 11.7/1000 person‐years at risk. The FRAX model included all variables in FRAX except bone mineral density. The full model combining FRAX variables, comorbidity, medications, and behavioral factors explained 25% to 45% of all fractures and 80% to 92% of hip fractures, depending on age. The corresponding prognostic values of the FRAX model were 7% to 17% for all fractures and 41% to 60% for hip fractures. Net reclassification improvement (NRI) comparing the full model with the FRAX model ranged between 40% and 53% for any fracture and between 40% and 87% for hip fracture. Within the highest quintile of predicted fracture risk with the full model, one‐third of the men will have a fracture within 10 years after age 71 years and two‐thirds after age 82 years. We conclude that the addition of comorbidity, medication, and behavioral factors to the clinical components of FRAX can substantially improve the ability to identify men at high risk of fracture, especially hip fracture. © 2012 American Society for Bone and Mineral Research.  相似文献   
146.
Following parathyroidectomy (PTX), bone mineral density (BMD) increases in patients with primary hyperparathyroidism (PHPT), yet information is scarce concerning changes in bone structure and strength following normalization of parathyroid hormone levels postsurgery. In this 1‐year prospective controlled study, high‐resolution peripheral quantitative computed tomography (HR‐pQCT) was used to evaluate changes in bone geometry, volumetric BMD (vBMD), microarchitecture, and estimated strength in female patients with PHPT before and 1 year after PTX, compared to healthy controls. Twenty‐seven women successfully treated with PTX (median age 62 years; range, 44–75 years) and 31 controls (median age 63 years; range, 40–76 years) recruited by random sampling from the general population were studied using HR‐pQCT of the distal radius and tibia as well as with dual‐energy X‐ray absorptiometry (DXA) of the forearm, spine, and hip. The two groups were comparable with respect to age, height, weight, and menopausal status. In both radius and tibia, cortical (Ct.) vBMD and Ct. thickness increased or were maintained in patients and decreased in controls (p < 0.01). Radius cancellous bone architecture was improved in patients through increased trabecular number and decreased trabecular spacing compared with changes in controls (p < 0.05). No significant cancellous bone changes were observed in tibia. Estimated bone failure load by finite element modeling increased in patients in radius but declined in controls (p < 0.001). Similar, albeit borderline significant changes in estimated failure load were found in tibia (p = 0.06). This study showed that females with PHPT had improvements in cortical bone geometry and increases in cortical and trabecular vBMD in both radius and tibia along with improvements in cancellous bone architecture and estimated strength in radius 1 year after PTX, reversing or attenuating age‐related changes observed in controls. © 2012 American Society for Bone and Mineral Research.  相似文献   
147.
Hohman DW  Ferrick MR  Qvick LM 《Orthopedics》2012,35(3):e457-e459
Brace treatment for idiopathic scoliosis in skeletally immature children is the only effective nonoperative modality for the control of curve progression. The Charleston bending brace is a custom-molded spinal orthosis that holds the patient in a completely corrected or overcorrected position while worn at night. A 9-year-old girl presented with 10° right upper thoracic and 7° left lower thoracic curves and was Risser sign 0. Nighttime treatment with a Charleston bending brace was initiated when the left lower thoracic curve progressed to 19°. After 27 months of nighttime brace wear, the lower thoracic curve was 21° to the right. Further investigation, including magnetic resonance imaging of the spine, failed to diagnose an identifiable explanation for this atypical occurrence. Conservative treatment may improve radiographic and cosmetic appearance. Overcorrection of the curve, although not likely, is possible when part-time or nighttime bracing is implemented as a means of conservative management.  相似文献   
148.

Purpose  

Bone defects resulting from tumour resection or curettage are most commonly reconstructed with autologous bone graft which is associated with limited availability and donor site morbidity. Recent research has focussed on synthetic biomaterials as bone graft substitutes. The aim of this study was to assess the safety and efficiency of a bone substitute as an alternative for autologous bone in the treatment of benign bone tumours and tumour-like lesions.  相似文献   
149.
BackgroundManagement of patients with severe concomitant carotid and coronary disease remains controversial. We report our experience of combined carotid endarterectomy (CEA) and coronary artery bypass surgery (CABG) over a fifteen year period using strict patient selection criteria.MethodsFrom 1st January 1995 to December 31st 2009 165 patients underwent combined CABG/CEA procedures at the Mater Hospital. Mean age was 68.2 years (range 43–88) and 127 (77%) were male. Fifty-three (32%) had symptomatic carotid disease. Indications for combined procedures were the presence of symptomatic >70% or asymptomatic >80% internal carotid artery stenosis in a patient requiring urgent CABG because of either unstable angina, recent MI, severe triple vessel disease or severe Left Anterior Descending or Left Main Stem stenosis.ResultsThirty-day stroke and death rate was 3%. All neurological events were in the hemisphere contralateral to the carotid surgery and symptoms had completely resolved prior to discharge from hospital. One patient required evacuation of a cervical haematoma and there were two transient XII nerve palsies.ConclusionCombined CEA/CABG can be performed safely with acceptable morbidity and mortality in patients selected in accordance with strict criteria in a centre with a large experience of both cardiac and carotid surgery.  相似文献   
150.

Background

Tadalafil improved lower urinary tract symptoms (LUTS) suggestive of benign prostatic hyperplasia (BPH; LUTS/BPH) in clinical studies but has not been evaluated together with an active control in an international clinical study.

Objective

Assess tadalafil or tamsulosin versus placebo for LUTS/BPH.

Design, setting, and participants

A randomised, double-blind, international, placebo-controlled, parallel-group study assessed men ≥45 yr of age with LUTS/BPH, International Prostate Symptom Score (IPSS) ≥13, and maximum urinary flow rate (Qmax) ≥4 to ≤15 ml/s. Following screening and washout, if needed, subjects completed a 4-wk placebo run-in before randomisation to placebo (n = 172), tadalafil 5 mg (n = 171), or tamsulosin 0.4 mg (n = 168) once daily for 12 wk.

Measurements

Outcomes were assessed using analysis of covariance (ANCOVA) or ranked analysis of variance (ANOVA) (continuous variables) and Cochran-Mantel-Haenszel test or Fisher exact test (categorical variables).

Results and limitations

IPSS significantly improved versus placebo through 12 wk with tadalafil (−2.1; p = 0.001; primary efficacy outcome) and tamsulosin (−1.5; p = 0.023) and as early as 1 wk (tadalafil and tamsulosin both −1.5; p < 0.01). BPH Impact Index significantly improved versus placebo at first assessment (week 4) with tadalafil (−0.8; p < 0.001) and tamsulosin (−0.9; p < 0.001) and through 12 wk (tadalafil −0.8, p = 0.003; tamsulosin −0.6, p = 0.026). The IPSS Quality-of-Life Index and the Treatment Satisfaction Scale–BPH improved significantly versus placebo with tadalafil (both p < 0.05) but not with tamsulosin (both p > 0.1). The International Index of Erectile Function–Erectile Function domain improved versus placebo with tadalafil (4.0; p < 0.001) but not tamsulosin (−0.4; p = 0.699). Qmax increased significantly versus placebo with both tadalafil (2.4 ml/s; p = 0.009) and tamsulosin (2.2 ml/s; p = 0.014). Adverse event profiles were consistent with previous reports. This study was limited in not being powered to directly compare tadalafil versus tamsulosin.

Conclusions

Monotherapy with tadalafil or tamsulosin resulted in significant and numerically similar improvements versus placebo in LUTS/BPH and Qmax. However, only tadalafil improved erectile dysfunction.

Trial registration

Clinicaltrials.gov ID NCT00970632  相似文献   
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