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81.
BACKGROUND: Evidence from animal studies indicate a crucial role for CD25(bright+) regulatory T cells in transplantation tolerance. METHODS: To assess whether peripheral CD25(bright+) T cells control immune responses in immunosuppressed kidney transplant patients, we analyzed the suppressive capacities of these cells using mixed lymphocytes reactions. RESULTS: Allogeneic stimulation of patients peripheral blood mononuclear cells was associated with IL-2 production and T-cell proliferation. Depletion of CD25(bright+) T cells resulted in a 35% (median) higher IL-2 production and a 38% higher proliferative response against third party cells, showing that functional regulatory CD25(bright+) T cells were present (p = 0.03 and 0.02 respectively). In eight out of 11 patients, we also demonstrated regulation activity against donor-activated T cells (p = 0.03). These data were confirmed in coculture experiments with isolated CD25(-/dim) T cells plus CD25(bright+) T cells. At a 1:2 ratio, the CD25(bright+) T cells suppressed the proliferation of CD25(-/dim) donor- and third party-stimulated responder T cells. CONCLUSIONS: CD25(bright+) T cells with immune regulatory activities against anti-donor-responsive T cells are readily detectable in renal allograft recipients during treatment with full dosage immunosuppression. Whether CD25(bright+) T cells indeed play a role in graft acceptance after organ transplantation in patients remains to be elucidated.  相似文献   
82.

Background

In breast conservation surgery (BCS) for breast cancer, the appropriate surgical margin is controversial. Margin index, a mathematical relationship between tumor size and closest margin, has been shown to be predictive of the probability of residual cancer after BCS for early stage breast cancer. We applied this tool to the same population of patients at our institution to evaluate its ability to predict residual disease after BCS.

Methods

We retrospectively reviewed a prospectively maintained database of women undergoing BCS between 1980 and 2010 at the University of Pennsylvania. A total of 246 women underwent re-excision because of close margins. Average margin index between groups with and without residual disease in the re-excision specimen was compared using the Student t-test. A receiver operating curve was created using logistic regression to assess the overall diagnostic ability of the margin index on the presence or absence of residual disease.

Results

Of patients who underwent re-excision, 29% of patients had residual disease. We analyzed several cutoff values for margin index, but none proved to be significant predictors of residual disease. Average margin index was significantly higher for patients without residual disease compared with patients with residual invasive cancer but not for patients with residual ductal carcinoma in situ.

Conclusions

In women undergoing BCS for early stage breast cancer at our institution, margin index was not predictive of the presence of residual cancer on re-excision. We hypothesize that the predictive ability of a margin index is likely limited by several factors including the presence of ductal carcinoma in situ and the location and extent of the close margin.  相似文献   
83.

Introduction

Although most studies report high frequencies of consent to HIV tests, critics argue that clients are subject to pressure, that acceptors later indicate they could not have refused, and that provider-initiated HIV testing raises serious ethical issues. We examine the meaning of consent and why clients think they could not have refused.

Methods

Clients in Burkina Faso, Kenya, Malawi and Uganda were asked about consenting to HIV tests, whether they thought they could have refused and why. Textual responses were analyzed using qualitative and statistical methods.

Results

Among 926 respondents, 77% reported they could not have said no, but in fact, 60% actively consented to test, 24% had no objection and only 7% tested without consent. There were few significant associations between categories of consent and their covariates.

Conclusions

Retrospectively asking clients if they could have refused to test for HIV overestimates coercion. Triangulating qualitative and quantitative data suggests a considerable degree of agency.  相似文献   
84.
This case report assessed quality of life, activities of daily living, motor symptoms, functional ability, neuromuscular parameters and mRNA expression of selected genes related to muscle protein synthesis and degradation in a patient with Multiple System Atrophy (MSA). The patient underwent resistance training with instability devices (i.e., bosu, dyna disk, balance disk, Swiss ball) for six months twice a week. After the six months training, the patient’s left and right quadriceps muscle cross-sectional area and leg press one-repetition maximum increased 6.4%, 6.8%, and 40%, respectively; the patient’s timed up and go, sit to stand, dynamic balance, and activities of daily living improved 33.3%, 28.6%, 42.3%, and 40.1%, respectively; the patient’s severity of motor symptoms and risk of falls decreased 32% and 128.1%, respectively. Most of the subscales of quality of life demonstrated improvements as well, varying from 13.0% to 100.0%. mRNA expression of mechanogrowth factor and mammalian target of rapamycin increased 12.7-fold and 1.5-fold, respectively. This case report describes likely the first nonpharmacological therapeutic tool that might be able to decrease the severity of motor symptoms and risk of falls, and to improve functional ability, neuromuscular parameters, and quality of the life in a patient with MSA.

Key points

  • Six months of resistance training with instability alleviate the MSA-related effects and improve the quality of life in a patient with MSA.
  • High complexity exercise intervention (i.e., resistance training with instability) may be very beneficial to individuals with impaired motor control and function as MSA patients.
  • Caution should be exercised when interpreting our findings as they cannot be generalized to the entire MSA population and they do not allow establishing causal conclusions on the effects of this mode of exercise on MSA.
Key words: Exercise training, risk of falls, motor symptoms, cross-sectional area  相似文献   
85.
The purpose of this study was to sequentially monitor anti‐HLA antibodies and correlate the results with antibody‐mediated rejection (AMR), graft survival (GS), and graft function (GF). We collected sera from 111 kidney transplant recipients on transplant days 0, 7, 14, 30, 60, 90, 180, and 360 and analyzed PRA levels by ELISA. DSAs were analyzed by single‐antigen beads in rejecting kidneys. At pre‐transplant, 79.3% of the patients were non‐sensitized (PRA = 0%) and 20.7% were sensitized (PRA > 1%). After transplant, patients were grouped by PRA profile: no anti‐HLA antibodies pre‐ or post‐transplant (group HLApre?/post?; n = 80); de novo anti‐HLA antibodies post‐transplant (group HLApre?/post+; n = 8); sensitized pre‐transplant/increased PRA post‐transplant (group HLApre+/post↑; n = 9); and sensitized pre‐transplant/decreased PRA post‐transplant (group HLApre+/post↓; n = 14). De novo anti‐HLA antibodies were detected at 7–180 d. In sensitized patients, PRA levels changed within the first 30 d post‐transplant. Incidence of AMR was higher in HLApre?/post+ and HLApre+/post↑ than in HLApre?/post?, and HLApre+/post↓ (p < 0.001) groups. One‐yr death‐censored GS was 36% in group HLApre+/post↑, compared with 98%, 88% and 100% in groups HLApre?/post?, HLApre?/post+, and HLApre+/post↓, respectively (p < 0.001). Excluding first‐year graft losses, GF and GS were similar among the groups. In conclusion, post‐transplant antibody monitoring can identify recipients at higher risk of AMR.  相似文献   
86.
The ability of the anterior cruciate ligament (ACL) to heal after injury declines within the first 2 weeks after ACL rupture. To begin to explore the mechanism behind this finding, we quantified the expression of genes for collagen I and III, decorin, tenascin‐C, and alpha smooth muscle actin, as well as matrix metalloproteinase (MMP)‐1 and ‐13 gene expression within multiple tissues of the knee joint after ACL injury in a large animal model over a 2‐week postinjury period. Gene expression of collagen I and III, decorin, and MMP‐1 was highest in the synovium, whereas the highest MMP‐13 gene expression levels were found in the ACL. The gene expression for collagen and decorin increased over the 2 weeks to levels approaching that in the ligament and synovium; however, no significant increase in either of the MMPs was found in the provisional scaffold. This suggests that although the ACL and synovium up‐regulate both anabolic and catabolic factors, the provisional scaffold is primarily anabolic in function. The relative lack of provisional scaffold formation within the joint environment may thus be one of the key reasons for ACL degradation after injury.  相似文献   
87.

Purpose

Scaphoid fractures are commonly fixed with headless cannulated screws positioned centrally in the scaphoid. Judgement of central placement of the screw may be difficult. We generated a central zone using computer analysis of 3D reconstructions of computed tomography (CT) images. As long as the screw axis is completely contained within this central zone, the screw would be considered as centrally placed.

Methods

Thirty cases of 3D CT reconstructions of normal scaphoids in a computerised operation planning and simulation system (Vxwork software) were obtained. The central zone was established after some distance shrinkage of the original scaphoid surface reconstruction model using the function “erode” in the software. The shape of the central zone was evaluated, and the width of the central zone in the proximal pole, waist portion and distal pole was measured. We also established the long axis of the scaphoid to see whether it stays in the central zone.

Results

All central zones could be divided into distal, waist and proximal portions according to the corresponding irregular shape of the scaphoid. As the geometry of the central zone was so irregular and its width very narrow, it was possible to completely contain the screw axis either in the proximal portion alone, waist alone or distal central zone alone.

Conclusions

Establishing the central zone of scaphoid 3D CT images provided a baseline for discussion of central placement of a scaphoid screw. The geometry of the scaphoid central zone determined that the screw could hardly be inserted through entire scaphoid central area during surgery.  相似文献   
88.
BackgroundThe combination of preoperative deficiencies and the restrictions and malabsorption possibly induced by bariatric surgery could lead patients to experience important nutritional deficits during the late postoperative period. Our objective was to characterize the eating, anthropometric, and biochemical profiles of obese candidates for bariatric surgery at a bariatric surgery center of a university hospital.MethodsA retrospective study with the analysis of medical records of candidates for bariatric surgery from 2007 to 2008 was performed. A total of 80 adult patients, aged 45 ± 11 years, were included in the present study.ResultsThe mean patient weight was 145 ± 24 kg, and the mean body mass index was 54 ± 8 kg/m2. Of the 80 patients, 78% had ≥1 co-morbidities related to obesity. The reported daily energy intake before surgery was 1981 ± 882 kcal, with 48% ± 11% consisting of carbohydrate, 29% ± 8% of lipids, and 23% ± 8% of protein. The mean number of daily meals was 4 ± 1. Patients with a greater body mass index ingested a smaller amount of calories per kilogram of current weight. The occurrence of hyperglycemia, hyperuricemia, and dyslipidemia and of nutritional deficiencies, among them magnesium (19%), vitamin A (15%), vitamin C (16%), iron (9%), β-carotene (3%), and vitamin B12 (3%), was high.ConclusionThe high occurrence of micronutrient deficiency detected by biochemical analysis in morbidly obese candidates for bariatric surgery, representing a disabsorptive process, might involve a poorer prognosis during the late postoperative period. A preoperative evaluation of the nutritional parameters and the food intake pattern is recommended for these patients, together with the necessary interventions.  相似文献   
89.
A "closed bath" cremaster muscle preparation is described which permits the administration of vasoactive materials to the microvasculature via intraarterial injection and topical suffusion. The technique is evaluated in spontaneously hypertensive (SHR) and Wistar-Kyoto (WKY) rats by comparing arteriolar responses to intraarterial and topically suffused arginine vasopressin. The preparation utilizes a thermostatically heated brass suffusion chamber overlying the cremaster. The chamber is closed with a glass coverslip. Experimental materials are presented to the microvessels via intraarterial injection or suffusion through the chamber. The coverglass permits high optical resolution with both routes of administration. Following vasopressin administration, changes in arteriolar diameter were continuously monitored by image-shearing techniques or variable-resistance calipers. The responses were analyzed by comparing both the peak 5-sec vasoconstriction and a 60-sec integrated response. Intraarterial and topical suffusion of vasopressin (1.25 X 10(-10)-3.75 X 10(-7) M) caused dose-dependent vasoconstriction among 23-microns arterioles. Compared to the WKY, vasoconstriction was greater in the SHR when vasopressin was administered intraarterially. A similar strain difference was not observed with topical suffusion. The dose-response curves with intraarterial vasopressin were shifted approximately 100-fold in concentration to the right relative to those with topically suffused vasopressin. The "closed bath" cremaster muscle preparation described has several distinct advantages: (1) it permits introduction of different vasoactive materials in the most physiological manner in the same animal, and (2) it maintains high optical resolution and clarity for critical observation of the smallest vessels, even with suffusion.  相似文献   
90.
Purpose

To compare the accuracy of Contrast-Enhanced Spectral Mammography (CESM), MG, US, and breast MRI in estimating the size of breast lesions requiring surgery. The postoperative histology size of the lesion was used as the gold standard.

Material and methods

Two hundred thirty-three non-benign lesions in 189 patients were included in the analyses. All the selected patients underwent CESM and at least one other conventional diagnostic exam (US, MG, or MRI). Subsequently, all the patients underwent surgery preceded by cytological/histological examination. The largest diameter of the lesion at imaging was measured by a radiologist with more than 10 years’ experience and then compared with the size of the lesion in the histological sample at the surgery (gold standard).

Results

Among the 233 breast lesions, 196 were evaluated with US, 206 with MG and 160 with MRI. We found no statistically significant differences between size measurements using CESM and MRI compared with the measurements at the surgery (p value 0.63 and 0.51), whereas a significant difference was found for MG and US (p?<?0.001).

Conclusion

CESM is a reliable method for estimating the size of breast lesions: its performance seems superior to US and MG and comparable to MRI.

  相似文献   
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