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71.
Research suggests that end-stage renal disease patients with elevated body mass index (BMI) have superior outcomes on dialysis. In contrast, low and high BMI patients represent the highest risk cohorts for kidney transplant recipients. The important question remains concerning how to manage transplant candidates given the potentially incommensurate impact of BMI by treatment modality. We conducted a retrospective analysis of waitlisted and transplanted patients in the United States from 1990 to 2003. We constructed Cox models to evaluate the effect of BMI on mortality of waitlisted candidates and identified risk factors for rapid weight change. We then assessed the impact of weight change during waitlisting on transplant outcomes. Decline in BMI on the waiting list was not protective for posttransplant mortality or graft loss across BMI strata. Substantial weight loss pretransplantation was associated with rapid gain posttransplantation. The highest risk for death was among listed patients with low BMI (13-20 kg/m(2), adjusted hazard ratio = 1.47, p < 0.01). Approximately one-third of candidates had a change in BMI category prior to transplantation. While observed declines in BMI may be volitional or markers of disease processes, there is no evidence that candidates have improved transplant outcomes attributable to weight loss. Prospective trials are needed to evaluate the efficacy of weight loss protocols for candidates of kidney transplantation.  相似文献   
72.

Background

The genu valgum deformity seen in the Ellis-van Creveld syndrome is one of the most severe angular deformities seen in any orthopaedic condition. It is likely a combination of a primary genetic-based dysplasia of the lateral portion of the tibial plateau combined with severe soft-tissue contractures that tether the tibia into valgus deformations. Progressive weight-bearing induces changes, accumulating with growth, acting on the initially distorted and valgus-angulated proximal tibia, worsening the deformity with skeletal maturation. The purpose of this study is to present a relatively large case series of a very rare condition that describes a surgical technique to correct the severe valgus deformity in the Ellis-van Creveld syndrome by combining extensive soft-tissue release with bony realignment.

Methods

A retrospective review examined 23 limbs in 13 patients with Ellis-van Creveld syndrome that were surgically corrected by two different surgeons from 1982 to 2011. Seven additional patients were identified, but excluded due to insufficient chart or radiographic data. A successful correction was defined as 10° or less of genu valgum at the time of surgical correction. Although not an outcomes study, maintenance of 20° or less of genu valgum was considered desirable. Average age at surgery was 14.7 years (range 7–25 years). Clinical follow-up is still ongoing, but averages 5.0 years (range 2 months to 18 years). Charts and radiographs were reviewed for complications, radiographic alignment, and surgical technique. The surgical procedure was customized to each patient’s deformity, consisting of the following steps:
  1. Complete proximal to distal surgical decompression of the peroneal nerve
  2. Radical release and mobilization of the severe quadriceps contracture and iliotibial band contracture
  3. Distal lateral hamstring lengthening/tenotomy and lateral collateral ligament release
  4. Proximal and distal realignment of the subluxed/dislocated patella, medial and lateral retinacular release, vastus medialis advancement, patellar chondroplasty, medial patellofemoral ligament plication, and distal patellar realignment by Roux-Goldthwait technique or patellar tendon transfer with tibial tubercle relocation
  5. Proximal tibial varus osteotomy with partial fibulectomy and anterior compartment release
  6. Occasionally, distal femoral osteotomy

Results

In all cases, the combination of radical soft-tissue release, patellar realignment and bony osteotomy resulted in 10° or less of genu valgum at the time of surgical correction. Complications of surgery included three patients (five limbs) with knee stiffness that was successfully manipulated, one peroneal nerve palsy, one wound slough and hematoma requiring a skin graft, and one pseudoarthrosis requiring removal of hardware and repeat fixation. At last follow-up, radiographic correction of no more than 20° of genu valgum was maintained in all but four patients (four limbs). Two patients (three limbs) had or currently require revision surgery due to recurrence of the deformity.

Conclusion

The operative approach presented in this study has resulted in correction of the severe genu valgum deformity in Ellis-van Creveld syndrome to 10° or less of genu valgum at the time of surgery. Although not an outcomes study, a correction of no more than 20° genu valgum has been maintained in many of the cases included in the study. Further clinical follow-up is still warranted.

Level of evidence

IV.  相似文献   
73.
74.
75.
Multisection proton MR spectroscopy for mesial temporal lobe epilepsy   总被引:8,自引:0,他引:8  
BACKGROUND AND PURPOSE: Extensive metabolic impairments have been reported in association with mesial temporal lobe epilepsy (mTLE). We investigated whether proton MR spectroscopy ((1)H-MRS) depicts metabolic changes beyond the hippocampus in cases of mTLE and whether these changes help lateralize the seizure focus. METHODS: MR imaging and (1)H-MRS were performed in 15 patients with mTLE with a postoperative diagnosis of mesial temporal sclerosis and in 12 control volunteers. Point-resolved spectroscopy and multisection (1)H-MRS measured N-acetylaspartate (NAA), creatine (Cr), and choline (Cho) in the hippocampus, temporal opercular and lateral cortices, insula and cerebellum, and frontal, parietal, and occipital lobes. Metabolites were assessed as ratios to Cr and in absolute units. RESULTS: Twelve patients had ipsilateral hippocampal atrophy; three had negative imaging results. In the ipsilateral hippocampus, absolute NAA (/NAA/) was 27.3% lower in patients compared with that in control volunteers (P <.001) and 18.5% lower compared with that in the contralateral side (P <.01). /NAA/ averaged over selected regions in the ipsilateral temporal lobes of patients with mTLE was 19.3% lower compared with the mean in the control group (P <.0001) and by 17.7% lower compared with the contralateral values (P <.00001). Using only hippocampal data, 60% of the cases of mTLE were correctly lateralized. Lateralization, determined using whole temporal lobe data, had 87% sensitivity and 92% specificity. /NAA/ was bilaterally reduced in the frontal, parietal, and occipital lobes of patients with mTLE compared with that in control volunteers (P <.01). CONCLUSION: Multisection (1)H-MRS depicts interictal reductions of NAA in the ipsilateral temporal lobe beyond the hippocampus and accurately lateralizes seizure foci.  相似文献   
76.
In kidney transplant recipients, cardiovascular disease (CVD) is the leading cause of death. The relationship of kidney function with CVD outcomes in transplant recipients remains uncertain. We performed a post hoc analysis of the Folic Acid for Vascular Outcome Reduction in Transplantation (FAVORIT) Trial to assess risk factors for CVD and mortality in kidney transplant recipients. Following adjustment for demographic, clinical and transplant characteristics, and traditional CVD risk factors, proportional hazards models were used to explore the association of estimated GFR with incident CVD and all‐cause mortality. In 4016 participants, mean age was 52 years and 20% had prior CVD. Mean eGFR was 49±18 mL/min/1.73 m2. In 3676 participants with complete data, there were 527 CVD events over a median of 3.8 years. Following adjustment, each 5 mL/min/1.73 m2 higher eGFR at levels below 45 mL/min/1.73 m2 was associated with a 15% lower risk of both CVD [HR = 0.85 (0.80, 0.90)] and death [HR = 0.85 (0.79, 0.90)], while there was no association between eGFR and outcomes at levels above 45 mL/min/1.73 m2. In conclusion, in stable kidney transplant recipients, lower eGFR is independently associated with adverse events, suggesting that reduced kidney function itself rather than preexisting comorbidity may lead to CVD.  相似文献   
77.
Outcome after Laparoscopic Adjustable Gastric Banding – 8 Years Experience   总被引:6,自引:12,他引:6  
Background: Laparoscopic adjustable gastric banding (LAGB) has been our choice operation for morbid obesity since 1994. Despite a long list of publications about the LAGB during recent years, the evidence with regard to long-term weight loss after LAGB has been rather sparse. The outcome of the first 100 patients and the total number of 984 LAGB procedures were evaluated. Methods: 984 consecutive patients (82.5% female) underwent LAGB. Initial body weight was 132.2 ± 23.9 SD kg and body mass index (BMI) was 46.8 ± 7.2 kg/m2. Mean age was 37.9 (18-65). Retrogastric placement was performed in 577 patients up to June 1998. Thereafter, the pars flaccida to perigastric (two-step technique) was used in the following 407 patients. Results: Mortality and conversion rates were 0. Follow-up of the first 100 patients has been 97% and ranges in the following years between 95% and 100% (mean 97.2%). Median follow-up of the first 100 patients who were available for follow-up was 98.9 months (8.24 years). Median follow-up of all patients was 55.5 months (range 99-1). Early complications were 1 gastric perforation after previous hiatal surgery and 1 gastric slippage (band was removed). All complications were seen during the first 100 procedures. Late complications of the first 100 cases included 17 slippages requiring reinterventions during the following years; total rate of slippage decreased later to 3.7%. Mean excess weight loss was 59.3% after 8 years, if patients with band loss are excluded. BMI dropped from 46.8 to 32.3 kg/m2. 5 patients of the first 100 LAGB had the band removed, followed by weight gain; 3 of the 5 patients underwent laparoscopic Roux-en-Y gastric bypass (LRYGBP) with successful weight loss after the redo-surgery. 14 patients were switched to a "banded" LRYGBP and 2 patients to a LRYGBP during 2001-2002. The quality of life indices were still improved in 82% of the first 100 patients. The percentages of good and excellent results were at the highest level at 2 years after LAGB (92%). Conclusions: LAGB is safe, with a lower complication rate than other bariatric operations. Reoperations can be performed laparoscopically with low morbidity and short hospitalizations. The LAGB seems to be the basic bariatric procedure, which can be switched laparoscopically to combined bariatric procedures if treatment fails. After the learning curve of the surgeon, results are markedly improved. On the basis of 8 years long-term follow-up, it is an effective procedure.  相似文献   
78.
Data from 565 knee arthroscopies performed by two experienced knee surgeons between 2002 and 2005 for degenerative joint disorders, ligament injuries, loose body removals, lateral release of the patellar retinaculum, plica division, and adhesiolysis was prospectively collected. A subset of 109 patients from the above group who sequentially had clinical examination, MRI and arthroscopy for suspected meniscal and ligament injuries were considered for the present study and the data was reviewed. Patients with previous menisectomies, knee ligament repairs or reconstructions and knee arthroscopies were excluded from the study. Patients were categorised into three groups on objective clinical assessment: Those who were positive for either meniscal or cruciate ligament injury [group 1]; both meniscal and cruciate ligament injury [group 2] and those with highly suggestive symptoms and with negative clinical signs [group 3]. MRI was requested for confirmation of diagnosis and for additional information in all these patients. Two experienced radiologists reported MRI films. Clinical and MRI findings were compared with Arthroscopy as the gold standard. A thorough clinical examination performed by a skilled examiner more accurately correlated at Arthroscopy. MRI added no information in group 1 patients, valuable information in group 2 and was equivocal in group 3 patients. A negative MRI did not prevent an arthroscopy. In this study, specificity, positive and negative predictive values were more favourable for clinical examination though MRI was more sensitive for meniscal injuries. The use of MRI as a supplemental tool in the management of meniscal and ligament injuries should be highly individualised by an experienced surgeon.  相似文献   
79.

Aims

Rhabdomyosarcoma (RMS) is the most common soft tissue tumor of childhood. Patient age, size, histologic finding, and site of the tumor are primary determinants of prognosis in RMS. Chest wall RMS is a site in which the limitations of surgical excision are realized. We aim to determine the impact of surgical excision in chest wall RMS.

Methods

A retrospective chart review was conducted of all 130 pediatric patients enrolled in the Intergroup Rhabdomyosarcoma Study (IRS) with chest wall rhabdomyosarcoma from the first (I) through fourth (IV) IRS with follow-up to June 2005. Median follow-up was 12.1 years (4.6-27.2 years).

Results

There was a significant improvement in failure-free survival (FFS) and overall survival (OS) between the first IRS study, I, and IRS-IV. The estimated FFS and OS at 5 years in IRS I was 30% and 40%, respectively, compared to 68% and 78%, respectively, in IRS-IV (P = .03 and P = .05, respectively). There was no association between histologic finding or size and FFS or OS. However, all patients who presented without metastasis had an FFS and OS of 49% and 61%, respectively, compared with metastatic patients, 7% and 7%, respectively (P < .001). Five-year FFS of group I, II, and III patients was 52%, 52%, and 45%, respectively, and OS was 65%, 60%, and 59%, respectively. There was no significant difference in 5-year FFS or OS in patients who had a complete resection (group I), complete resection with positive microscopic margins (group II), or biopsy or partial resection only (group III). In groups I to III patients, the local and regional failure rate at 5 years is 25% and 6%, respectively.

Conclusions

The most significant impact on outcome in chest wall RMS patients is metastatic disease at diagnosis. The locoregional failure rate is high but does not appear to impact survival. Alternative treatment strategies are needed for chest wall RMS, but aggressive surgical excision may not be necessary.  相似文献   
80.
Osteoarthritis (OA) is a degenerative cartilage disease with varying degrees of severity within a given joint. The purpose of this study was to define a sampling procedure for comparing human minimal and advanced OA cartilage in the same patient and to determine basic patterns of gene expression in these regions. A specific hypothesis under study was that the expression level of Bcl-2 would correlate with Sox9 and aggrecan mRNA expression in vivo as has been demonstrated in vitro. Femoral condylar advanced OA cartilage was located within 1cm of overt lesions, and minimal cartilage was taken from areas with no obvious surface defects. Histological sections were scored for disease severity and chondroitin sulfate and hydroxyproline content was determined. The expression level of nine specific genes (aggrecan, collagen type II, Bcl-2, Sox9, Link protein, osteopontin, and MMP-13, -3, and -9) was determined by quantitative real time PCR. The scores for fibrillation, chondrocyte cloning, and proteoglycan depletion were significantly different between advanced and minimal OA cartilage. The advanced OA cartilage had significantly less chondroitin sulfate than the minimal OA cartilage. Osteopontin mRNA expression showed a 3.6-fold increase in advanced compared to minimal OA cartilage. In contrast, the level of mRNA coding for aggrecan, link protein, Bcl-2, Sox9 and MMP-3, -9, -13 were all decreased in advanced compared to minimal cartilage in the majority of the patients studied. Collagen type II mRNA expression displayed a wide-range of variation. A statistically significant correlation was observed both between Bcl-2 and Sox9 mRNA level, and between Bcl-2 and aggrecan mRNA expression. The patient matched comparison of minimal and advanced OA cartilage revealed differences in cellular and tissue characteristics, and changes in gene expression that may be involved in OA progression. In addition, Bcl-2 may also play a role in regulating the expression of aggrecan through Sox9 in vivo as well as in vitro.  相似文献   
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