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971.
BACKGROUND: A single nucleotide polymorphism in the tumor necrosis factor type II receptor (TNFRII) gene, codon 196, results in the substitution of arginine (R allele) for methionine (M allele). The 196R allele is reportedly associated with an increased susceptibility to autoimmune disease, and donor 196R allele carriage correlates with increased severity of acute graft-versus-host disease (GVHD) after matched unrelated bone marrow transplantation (BMT). METHODS: We investigated the impact of donor and recipient TNFRII genotype on GVHD incidence and severity among 104 adult recipients of myeloablative sibling BMTs. RESULTS: 196R allele frequency was 0.28 among recipients, donors, and controls. There was an increased incidence of acute GVHD among 196R-positive recipients (odds ratio [OR] 3.6, P=0.05). This association was confirmed in multivariate analysis (relative risk 4, P=0.04), correcting for previously established clinical and genetic risk factors. Donor 196R homozygosity was associated with an increased incidence of extensive chronic GVHD (OR 18.5, P=0.02). This association was also confirmed in multivariate analysis (OR 11, P=0.02). To investigate the functional impact of the TNFRII 196 M/R polymorphism, 79 volunteer blood donors were genotyped at this locus, by polymerase chain reaction and single-strand conformational polymorphism analysis, and plasma soluble TNFRII (sTNFRII) levels were measured by ELISA. Mean plasma sTNFRII levels (pg/mL: +/-SEM) were 1224 (+/-26) and 1063 (+/-65) for 196M-postive (196 M homozygous or heterozygous) individuals and 196R homozygotes, respectively (P=0.02). CONCLUSIONS: Because sTNFRIIs can act as TNF antagonists, the association between recipient and donor TNFRII 196R allele status and acute or extensive chronic GVHD incidence, respectively, may reflect reduced circulating sTNFRII.  相似文献   
972.
OBJECTIVE: To determine if NF-kappa B regulates intestinal epithelial cell migration and if it has a role during bile salt-induced migration. SUMMARY BACKGROUND DATA: Mucosal restitution is an important repair modality in the gastrointestinal tract. The authors have shown that taurodeoxycholate (TDCA) increases intestinal epithelial cell migration. NF-kappa B regulates activation of a number of genes involved in inflammatory responses. METHODS: Studies were conducted in IEC-6 cells. I kappa B protein expression was determined by Western blot analysis. Sequence-specific NF-kappa B binding activity was measured by EMSA shift assays and nuclear localization by immunohistochemistry. Cell migration was examined by using an in vitro model that mimics the early cell division-independent stages of epithelial restitution. RESULTS: The process of cell migration over the wounded area was associated with a significant increase in NF-kappa B binding activity in IEC-6 cells. Immunohistochemistry revealed translocation of NF-kappa B into the nucleus. Western blot analysis showed that injury decreased I kappa B protein expression. Inhibition of the binding activity by treatment with a specific NF-kappa B inhibitor, MG-132, inhibited cell migration during restitution. Further, exposure to TDCA at the physiologic concentration that induces intestinal epithelial cell migration increased NF-kappa B binding activity, induced NF-kappa B translocation into the nucleus, and decreased I kappa B protein expression. MG-132 also inhibits bile salt-induced cell migration. CONCLUSIONS: NF-kappa B regulates intestinal epithelial cell migration. Bile salts at physiologic concentrations increase cell migration by activation of NF-kappa B. These data show that bile salts may have a role in the maintenance of intestinal mucosal integrity.  相似文献   
973.
INTRODUCTION: Elderly patients who suffer trauma have a higher mortality and use disproportionately more trauma resources than younger patients. To compare these 2 groups and determine the outcomes and characteristics of elderly patients, we reviewed patients in these 2 groups admitted and treated in our tertiary care provincial trauma centre. METHODS: From the provincial trauma registry we selected a cohort of 40 geriatric patients (group 1) (> or = 65 yr of age) with an ISS of 16 or more who were admitted to and spent time in our trauma service for more than 48 hours and compared them with a similar randomly selected cohort of 44 patients (group 2) aged 20-30 years. Family physicians were contacted for follow-up of these patients 2 years after discharge. We considered length of hospital stay, complications, disposition of the patients and use of consultation services. RESULTS: Patients in group 1 had a mean age of 72.1 years (range from 65-98 yr) and a mean ISS of 27.3 (range from 17-50). Patients in group 2 had a mean age of 26.3 years (range from 22-29 yr) and a mean ISS of 26.3 (range from 17-54). Hospital stay was significantly longer in the group 1: 34.5 days (95% confidence interval [CI]: 24-44 d) versus 21.6 days (95% CI: 15-28 d). More elderly patients experienced complications (35 v. 13, p < 0.001) and required medical consultations (35 v. 26, p < 0.001). In-hospital death rates were 8% (3 of 40) and 4% (2 of 44) respectively (p = 0.3). Fewer geriatric patients could be discharged home (35% [14 of 40] v. 27% [22 of 44], p = 0.056) or to rehabilitation facilities (28% [11 of 40] v. 34% [15 of 44], p = 0.3). Five geriatric patients were discharged to nursing homes (p = 0.007). Of the geriatric patients discharged to rehabilitation facilities or home, 75% were independent 2 years after discharge. CONCLUSIONS: Aggressive care for geriatric trauma patients is warranted, and resources should be directed toward rehabilitation. Based on our findings, we expect that creating a directed care pathway for these patients, targetting complications and earlier discharge, will further improve their outcomes.  相似文献   
974.
This study compares remifentanil/propofol (remi/prop) with isoflurane/fentanyl (iso/fen) anesthesia to determine which provides the greater hemodynamic stability, lesser myocardial ischemia, and morbidity with better postoperative outcomes after carotid endarterectomy. Sixty patients undergoing unilateral carotid endarterectomy were randomized to receive either a remi/prop or iso/fen anesthetic. Hemodynamic variables were recorded during the surgical procedure. In addition, transesophageal echocardiography was used to assess evidence of intraoperative regional wall motion abnormalities suggestive of cardiac ischemia. Emergence and extubation times, recovery from anesthesia, hemodynamic instability, nausea, vomiting, and pain in post anesthesia recovery, discharge delays, ICU admittance, hospital discharge, and preoperative and postoperative troponin levels were compared using appropriate statistical methods with P < 0.05 considered significant. The groups were demographically alike. Hemodynamic variables were similar during intubation and throughout surgery. Twenty-two percent of patients receiving iso/fen developed intraoperative regional wall motion abnormalities suggestive of ischemia, whereas no remi/prop patients had changes (P < 0.05). There was no difference in ST-T wave changes after surgery, and no patient had an elevation in troponin I levels. Postoperative variables were similar except that patients who received iso/fen had lower Stewart recovery scores during the first 15 minutes after post anesthesia care unit admission and a higher incidence of nausea and vomiting the day after surgery, whereas patients receiving remi/prop had discharge delays secondary to hypertension. ICU admittance, time to first void, oral intake, and time to hospital discharge were similar between the groups. At 9 times the cost of an iso/fen anesthesia technique, remi/prop offers little advantage over inhalational anesthesia for carotid endarterectomy.  相似文献   
975.
Development of a reconstructed human skin model for angiogenesis   总被引:4,自引:0,他引:4  
We have previously shown that reconstructed human skin engineered from autologous keratinocytes, fibroblasts, and sterilized donor allodermis stimulates angiogenesis within 5-7 days when placed on well-vascularized wound beds in nude mice. When this reconstructed skin was used clinically in more demanding wound beds, some grafts were lost, possibly due to delayed vascularization. As this reconstructed skin lacks any endothelial cells, our aim in this study was to develop an angiogenic reconstructed skin model in which to explore strategies to improve angiogenesis both in vitro and in vivo. We report that culture of small-vessel human dermal microvascular endothelial cells (HuDMECs) was achieved using magnetic beads coated with an antibody to platelet cell adhesion molecule as a means of purifying the culture. Keratinocytes, fibroblasts, and HuDMECs could be cultured from the same skin biopsy. Initial studies culturing HuDMECs and other sources of endothelial cells with the tissue-engineered skin showed that these cells were capable of slowly entering the dermis under standard culture conditions in vitro. In conclusion, this provides us with a model in which to explore strategies for improving angiogenesis in vitro and also establishes the culture methodologies for the production of reconstructed skin containing autologous keratinocytes, fibroblasts, and endothelial cells.  相似文献   
976.
Multicontrast magnetic resonance imaging (MRI) has shown promise in identifying and characterizing atherosclerotic plaques. One of the limitations of this technique is the lack of a practical automated plaque characterization scheme. In the current study, a prior-information-enhanced clustering (PIEC) technique that utilizes both multicontrast MR images and quantitative T(2) maps is proposed to characterize atherosclerotic plaque components automatically. The PIEC algorithm was assessed on computationally simulated images and multicontrast MRI data of coronary arteries. Multicontrast (T(1)-, T(2)-, partial T(2)-, and proton density-weighted) MR images were acquired from freshly excised human coronary arteries using a 4.7T small-animal scanner. The T(2) distribution for each plaque constituent was measured by exponentially fitting the signal from multiple MR images with different TEs and the same TR. The calculated T(2) distributions were used as the a priori information and combined with the Fuzzy C-Means (FCM)-based clustering algorithm to characterize plaque constituents. The proposed PIEC technique appears to be a promising algorithm for accurate automated plaque characterization.  相似文献   
977.
Cochlear implants may improve the medical and social prognosis of profound deafness. Nevertheless, some patients have experienced poor results without any clear explanations. One correlate may be an alteration in cortical voice processing. To test this hypothesis, we studied the activation of human temporal voice areas (TVA) using a well-standardized PET paradigm adapted from previous functional MRI (fMRI) studies. METHODS: A PET H(2)(15)O activation study was performed on 3 groups of adult volunteers: normal-hearing control subjects (n = 6) and cochlear-implanted postlingually deaf patients with >2 y of cochlear implant experience, with intelligibility scores in the "Lafon monosyllabic task" >80% (GOOD group; n = 6) or <20% (POOR group; n = 6). Relative cerebral blood flow was measured in 3 conditions: rest, passive listening to human voice, and nonvoice stimuli. RESULTS: Compared with silence, the activations induced by nonvoice stimuli were bilaterally located in the superior temporal regions in all groups. However these activations were significantly and similarly reduced in both cochlear implant groups, whereas control subjects showed supplementary activations. Compared with nonvoice, the voice stimuli induced bilateral activation of the TVA along the superior temporal sulcus (STS) in both the control and the GOOD groups. In contrast, these activations were not detected in the POOR group, which showed only left unilateral middle STS activation. CONCLUSION: These results suggest that PET is an adequate method to explore cochlear implant benefits and that this benefit could be linked to the activation of the TVA.  相似文献   
978.
Introduction  Several studies have shown the usefulness of positron emission tomography (PET) quantification using standardised uptake values (SUV) for diagnosis and staging, prognosis and response monitoring. Many factors affect SUV, such as patient preparation procedures, scan acquisition, image reconstruction and data analysis settings, and the variability in methodology across centres prohibits exchange of SUV data. Therefore, standardisation of 2-[18F] fluoro-2-deoxy-D-glucose (FDG) PET whole body procedures is required in multi-centre trials. Methods  A protocol for standardisation of quantitative FDG whole body PET studies in the Netherlands (NL) was defined. This protocol is based on standardisation of: (1) patient preparation; (2) matching of scan statistics by prescribing dosage as function of patient weight, scan time per bed position, percentage of bed overlap and image acquisition mode (2D or 3D); (3) matching of image resolution by prescribing reconstruction settings for each type of scanner; (4) matching of data analysis procedure by defining volume of interest methods and SUV calculations and; (5) finally, a multi-centre QC procedure is defined using a 20-cm diameter phantom for verification of scanner calibration and the NEMA NU 2 2001 Image Quality phantom for verification of activity concentration recoveries (i.e., verification of image resolution and reconstruction convergence). Discussion  This paper describes a protocol for standardization of quantitative FDG whole body multi-centre PET studies. Conclusion  The protocol was successfully implemented in the Netherlands and has been approved by the Netherlands Society of Nuclear Medicine. An erratum to this article can be found at  相似文献   
979.
980.
Background: Inadequate protein intake is a concern following Roux-en-Y gastric bypass (RYGBP). The small gastric pouch and bypass restrict energy intake and may lead to insufficient protein intake and absorption, and excess loss of lean tissue. Methods:We evaluated protein intake in 93 (77 F,16 M) morbidly obese individuals (BMI = 52.0±12.9 [SD]) who underwent RYGBP at our medical center. Participants completed 24-hr food recalls and received nutritional counseling at 3, 6, and 12 months following surgery. Results: Daily energy intake (kcal/day) increased from 849±329 (SD) at 3 months to 1,101±400 at 12 months (P=.009). Protein intake also increased (g/day) from 45.6±14.2 at 3 months to 58.5±17.1 at 12 months (P=.04), and as a percentage of goal protein intake from 55.1%±23.0 at 3 months to 73.5%±38.0 at 12 months (P=.02). Although energy and protein intake increased significantly over the 12-month period, protein intake at 12 months remained significantly lower (P=.01) than the daily recommended guidelines (1.5 g/kg IBW) for a low-energy restrictive diet. Energy intake did not differ in those who reported food intolerances at 3 months (P=.77) or 6 months (P=.65), but was lower in them at 12 months (trend, P=.06). Also at 12 months, protein intake (P=.02) and percentage of protein intake goal (P=.04) were significantly lower in those with protein intolerance. Conclusions: These results suggest that postoperative patients consume insufficient amounts of protein, possibly mediated by protein intolerance. Protein supplementation following RYGBP deserves further consideration.  相似文献   
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