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71.
We reviewed the arthroscopic findings in 16 knees in which a patellectomy had been performed 1–47 years previously (average 15.4 years). The study group consisted of 13 women and 3 men with an average age of 46.3 years (range 24–64 years). The knee symptoms had failed to respond to non-operative treatment and the treating surgeon (R.J.B.) had determined that arthroscopic examination was warranted. Fifteen of the 16 patients had articular cartilage damage, particularly in the medial compartment and trochlear groove. The severity of articular cartilage damage correlated with time since patellectomy, but not with patient age. Apart from the previous patellectomy, no predisposing factors could be identified to account for the frequency and severity of tibiofemoral osteoarthritis in this relatively young group of patients. Our findings suggest that there may be an association between patellectomy and the subsequent development of osteoarthritis.  相似文献   
72.
The effects of two antiinflammatory and neuroprotective agents, methylprednisolone (MP) and interleukin-10 (IL-10), singly and in combination on tissue damage, axonal preservation and functional recovery were studied in the contused adult Fischer rat thoracic spinal cord 12 weeks after injury. MP (30 mg/kg at 5 min, and 2 and 4 h after injury) was administered intravenously and IL-10 (15 or 30 microg/kg at 30 min after injury), intraperitoneally. MP, IL-10, or the combination significantly reduced the volume of damaged tissue (including cavities) compared to control animals. The loss of spinal tissue (cavities) was reduced after treatment with MP alone or combined with IL-10, but not with IL-10 alone. The reduction in tissue damage was confined to spinal gray matter; at the level of the lesion epicenter, the thickness of the lateral white matter columns was similar in all groups. Retrograde tracing using fast blue revealed that the number of spared propriospinal and supraspinal projections was similar in all groups at 12 weeks after the contusion. The open-field BBB-test showed no significant difference in hindlimb locomotion between groups. Our results demonstrate that all tested antiinflammatory treatments significantly increase the volume of spared spinal gray matter 3 months after a moderate contusion of the Fischer rat thoracic spinal cord, but none of the treatments improved axonal preservation or functional recovery.  相似文献   
73.
OBJECTIVE: To relate the repeat length of the androgen-receptor CAG trinucleotide to the age of onset of prostate cancer, stage and grade of disease. PATIENTS AND METHODS: After obtaining ethical approval, 265 patients with locally confined or locally advanced/metastatic prostate cancer were identified and evaluated for age at diagnosis (< 65 years and > 75 years). DNA was extracted from peripheral blood lymphocytes and 1 micro g aliquots subjected to polymerase chain reaction using fluorescently labelled primers. Samples were then run on an ABI 377 gene scan analysis gel with an internal molecular weight marker. The length of the CAG repeat was determined by comparing the gene scan product size to samples where the CAG repeat length had been quantified using direct sequencing. The Kruskal-Wallis, Mann-Whitney and Wilcoxon two sample tests were used to analyse the data. RESULTS: The mean (range) length of the CAG repeat in the androgen receptor was 22.2 (10-31) in the younger and 22.5 (16-32) in the older group, and was not statistically different. There was no significant association between the CAG repeat length and the age of onset of prostate cancer (P = 0.568) or with stage (P = 0.577) and grade (P = 0.891) of prostate cancer. CONCLUSION: These results suggest that there is no correlation between the androgen receptor CAG repeat length and the age of onset, stage and grade of prostate cancer, confirming recent doubts from other similar studies of a suggested correlation between shorter androgen receptor CAG repeat and early onset and aggressiveness of prostate cancer.  相似文献   
74.
An international panel reviewed the methodology for clinical trials of spinal cord injury (SCI), and provided recommendations for the valid conduct of future trials. This is the second of four papers. It examines clinical trial end points that have been used previously, reviews alternative outcome tools and identifies unmet needs for demonstrating the efficacy of an experimental intervention after SCI. The panel focused on outcome measures that are relevant to clinical trials of experimental cell-based and pharmaceutical drug treatments. Outcome measures are of three main classes: (1) those that provide an anatomical or neurological assessment for the connectivity of the spinal cord, (2) those that categorize a subject's functional ability to engage in activities of daily living, and (3) those that measure an individual's quality of life (QoL). The American Spinal Injury Association impairment scale forms the standard basis for measuring neurologic outcomes. Various electrophysiological measures and imaging tools are in development, which may provide more precise information on functional changes following treatment and/or the therapeutic action of experimental agents. When compared to appropriate controls, an improved functional outcome, in response to an experimental treatment, is the necessary goal of a clinical trial program. Several new functional outcome tools are being developed for measuring an individual's ability to engage in activities of daily living. Such clinical end points will need to be incorporated into Phase 2 and Phase 3 trials. QoL measures often do not correlate tightly with the above outcome tools, but may need to form part of Phase 3 trial measures.  相似文献   
75.
In recent times a steady rise in cranioplasty operations has been noted because of increasing utilisation of decompressive craniectomy for trauma as well as stroke patients. A variety of techniques have been utilised for cranioplasty, with their own benefits and limitations. Titanium cranioplasty is one of the well-established and widely used techniques, with most centres utilising computer-assisted reconstruction for manufacture of titanium plates. In this paper we present a novel method for making titanium cranioplasty plates using the craniectomy bone flap as a template and the results of our experience. To date we have performed 51 cranioplasties using this method. The surgical results have been comparable to those obtained using the computer-assisted model technique. The construction cost for titanium cranioplasty plates using this method has been £360 cheaper per plate compared with the computer-assisted method. In addition, the CT workload and radiation exposure have been reduced.  相似文献   
76.

Background  

Patients with ocular melanoma liver metastases have a poor prognosis, treatment options are limited, and median survival is less than 1 year. In this study, we characterized the early molecular changes that occur in tumors immediately after vascular isolation perfusion with melphalan with hyperthermia in patients with hepatic metastases from ocular melanoma.  相似文献   
77.
INTRODUCTION/OBJECTIVE: N-acetyltransferase 2 (NAT2), mapped to 8p22, is a polymorphic enzyme which metabolizes aromatic amines. Loss of heterozygosity of 8p22 is associated with an increased risk of bladder cancer. This study evaluated NAT2 and chromosome 8 in sequential tumours from bladder cancer patients to determine if NAT2 alterations increase the risk of progression. MATERIALS AND METHODS: Thirty-seven sequential carcinomas from 19 patients were assessed using fluorescence in situ hybridization. RESULTS: Five carcinomas showed loss of NAT2; 4 of these were from pTa/pT1 tumours. Polysomy 8 was observed in 4 of 14 (29%) primary carcinomas (pTa/pT1), in 4 of 12 (33%) pTa/pT1 recurrences, and in 90% (9/10) of the detrusor muscle invasive tumours (pT2+). 6 of 8 (75%) locally invasive tumours with polysomy 8 were from patients who subsequently developed disease progression (pT2+). In total, 13.5% (5/37) of the carcinomas were abnormal for NAT2, and 46% (17/37) were abnormal for chromosome 8 copy number. Polysomy 8 was associated with high grade (p = 0.01) and stage (p = 0.03) and disease progression (p = 0.03). CONCLUSION: Whilst there does not appear to be an association between loss of NAT2 and risk of progression in transitional cell carcinoma, the high rate of polysomy of chromosome 8 implies that other genes on this chromosome significantly influence disease progression.  相似文献   
78.
BACKGROUND: We have previously reported that activated CD8+TCRalphabeta+ cells that express high levels of the beta7 integrin CD103 (formerly alphaE, MLA) are present at the graft site during clinical renal allograft rejection. This observation potentially provides new insight into the mechanisms underlying renal allograft destruction because the ligand of CD103 is the epithelial cell-specific molecule E-cadherin, which is known to be expressed by critical graft functional elements such as the renal tubular epithelium. We herein used combined fluorescence-activated cell sorter (FACS) and immunohistochemical (IHC) analyses of transplant nephrectomy (TN) specimens to demonstrate that CD103+ cytolytic T lymphocytes (CTLs) specifically home to the graft epithelium during rejection episodes. METHODS: Serial sections of TN specimens undergoing histologically confirmed cellular rejection (n=7) were stained with anti-CD8 or anti-CD103 and were scored for the presence of positively stained cells within the tubular basement membrane. Freshly isolated graft-infiltrating lymphocytes were subjected to three-color FACS analyses to define the extended phenotypic characteristics of CD103+ cells detected by IHC. RESULTS: CD103+ cells in all specimens were biased towards an intratubular localization. On average, the percentage of CD103+ cells with an intraepithelial localization was 52.2+/-13.1 compared to 12.0+/-3.5 for pan CD8+ cells (mean+/-SE, n=5). FACS analyses confirmed that CD103+ cells detected by IHC exhibited the salient characteristics of CD8+ CTLs (large CD8+TCRalphabeta+CD62L-CD11a(hi)perforin+). The CD103- subset of graft-infiltrating CD8 cells also exhibited a CTL phenotype, but these were predominantly restricted to the graft interstitium. CONCLUSIONS: These data implicate CD103 as a homing receptor that targets graft-infiltrating CD8+ CTLs to the graft epithelium. Given the strong association of tubulitis with clinical rejection, these data are consistent with a role for the CD103+ CTL subset as an effector mechanism in renal allograft destruction.  相似文献   
79.

Background

The significance of tumor markers in patients with appendiceal carcinomatosis is poorly defined. We determined preoperative and postoperative tumor marker levels in patients undergoing cytoreductive surgery (CRS) and heated intraperitoneal chemoperfusion (HIPEC) and examined their association with clinicopathologic features and survival.

Methods

A total of 176 patients undergoing attempted CRS/HIPEC for appendiceal carcinomatosis had at least 1 tumor marker measured. Marker levels were correlated with tumor characteristics and oncologic outcomes. Kaplan–Meier curves and multivariate Cox regression models were used to identify prognostic factors affecting progression and survival.

Results

At least 1 marker was elevated prior to CRS/HIPEC in 70 % of patients (CEA, 54.1 %; CA19-9, 47.7 %; CA-125, 47.2 %). Among patients with elevated preoperative marker levels, normalization occurred postoperatively in 79.4 % for CEA, 92.3 % for CA19-9, and 60 % for CA-125. Absolute preoperative tumor marker levels correlated with peritoneal carcinomatosis index (PCI) (p < .0002), and the number of elevated markers was associated with PCI and progression-free survival (PFS). Elevated postoperative CEA level was associated with decreased PFS (median, 13 vs 36 months, p = .0008). On multivariate Cox regression analysis, elevated preoperative CA19-9 was associated with shorter PFS (hazard ratio [HR] 2.9, 95 % confidence interval [95 % CI] 1.5–5.3, p = .0008), whereas elevated CA-125 was associated with shorter overall survival (HR 2.6, 95 % CI 1.3–5.4, p = .01).

Conclusions

Most patients with appendiceal carcinomatosis will have at least 1 elevated tumor marker and will normalize following CRS/HIPEC, allowing for ongoing surveillance. CA19-9 is a promising biomarker for early progression following CRS/HIPEC, whereas CA-125 is associated with shorter survival.  相似文献   
80.
Procurement of a facial vascularized composite allograft (VCA) should allow concurrent procurement of all solid organs and ensure their integrity. Because full facial procurement is time–intensive, “simultaneous–start” procurement could entail VCA ischemia over 12 h. We procured a total face osteomyocutaneous VCA from a brain–dead donor. Bedside tracheostomy and facial mask impression were performed preoperative day 1. Solid organ recovery included heart, lungs, liver, kidneys, and pancreas. Facial dissection time was 12 h over 15 h to diminish ischemia while awaiting recipient preparation. Solid organ recovery began at 13.5 h, during midfacial osteotomies, and concluded immediately after facial explantation. Facial thoracic and abdominal teams worked concurrently. Estimated blood loss was 1300 mL, requiring five units of pRBC and two units FFP. Urine output, MAP, pH and PaO2 remained normal. All organs had good postoperative function. We propose an algorithm that allows “face first, concurrent completion” recovery of a complex facial VCA by planning multiple pathways to expedient recovery of vital organs in the event of clinical instability. Beginning the recipient operation earlier may reduce waiting time due to extensive recipient scarring causing difficult dissection.  相似文献   
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