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371.
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373.
Protection Against Ischemia/Reperfusion Injury in Cardiac and Renal Transplantation with Carbon Monoxide, Biliverdin and Both 总被引:9,自引:0,他引:9
Atsunori Nakao Joao Seda Neto Shinichi Kanno Donna B. Stolz Kei Kimizuka Fang Liu Fritz H. Bach Timothy R. Billiar Augustine MK. Choi Leo E. Otterbein Noriko Murase 《American journal of transplantation》2005,5(2):282-291
Both carbon monoxide (CO) and biliverdin, products of heme degradation by heme oxygenase, have been shown to attenuate ischemia/reperfusion (I/R) injury. We hypothesized in this study that dual-treatment with CO and biliverdin would induce enhanced protective effects against cold I/R injury. Heterotopic heart and orthotopic kidney transplantation were performed in syngeneic Lewis rats after 24-h cold preservation in UW solution. While monotherapy with CO (20 ppm) or biliverdin (50 mg/kg, ip) did not alter the survival of heart grafts, dual-treatment increased survival to 80% from 0% in untreated recipients, with a significant decrease of myocardial injury and improved cardiac function. Similarly, dual-treatment significantly improved glomerular filtration rates of renal grafts and prolonged recipient survival compared to untreated controls. I/R injury-induced up-regulation of pro-inflammatory mediators (e.g. TNF-alpha, iNOS) and extravasation of inflammatory infiltrates were significantly less with dual-treatment than untreated controls. In addition, dual-treatment was effective in decreasing lipid peroxidation and improving graft blood flow through the distinctive action of biliverdin and CO, respectively. The study shows that the addition of byproducts of heme degradation with different mechanisms of action provides enhanced protection against transplant-associated cold I/R injury of heart and kidney grafts. 相似文献
374.
375.
The purpose of this study was to investigate if a secular trend towards an earlier age of menarche still existed in Finland in the 1980s and if social class and regional differences observed previously in the mean age of menarche had disappeared. Questionnaires were mailed to nationwide representative samples of 16- and 18-year-old girls every other year from 1979 to 1989. At the national level, the secular trend towards an earlier menarche was not observed in the 1980s but the trend was significant among girls living in the North-West and rural areas. Clearly observed regional and urban-rural differences in 1979 disappeared in the 1980s. Social class differences persisted: farmers' daughters had a higher mean age of menarche than those of other occupational groups. Adolescents in the 1980s displayed a more even distribution of health than the cohorts born before them. Improved welfare of the Finnish society and reorganization of the primary health care are probable explanations. 相似文献
376.
Hassan MK Ghomrawi Lauren M Baumann Soyang Kwon Ferdynand Hebal Grace Hsiung Kibileri Williams Molly Reimann Christine Stake Emilie K Johnson Fizan Abdullah 《Journal of pediatric surgery》2018,53(8):1600-1605
Background
Assessment of recovery after surgery in children remains highly subjective. However, advances in wearable technology present an opportunity for clinicians to have an objective assessment of postoperative recovery. The aims of this pilot study are to: (1) evaluate acceptability of accelerometer use in pediatric surgical patients, (2) use accelerometer data to characterize the recovery trajectory of physical activity, and (3) determine if postoperative adverse events are associated with a decrease in physical activity.Study design
Children aged 3–18-years-old undergoing elective inpatient and outpatient surgical procedures were invited to participate. Physical activity was measured using an Actigraph GT3X wristworn accelerometer for ≥ 2 days preoperatively and 5–14 days postoperatively. Time spent performing light (LPA) and moderate-to-vigorous physical activity (MVPA) was expressed in minutes/day. Physical activity for each postoperative day was calculated as a percentage of preoperative activity, and recovery trajectories were produced. Adverse events were reported and mapped against recovery trajectories.Results
Of 60 patients enrolled, 25 (10 inpatients, 15 outpatients) completed the study procedures and were included in the analysis. For outpatient procedures, LPA recovered to preoperative level on postoperative day (POD) 7 and MVPA peaked at 90% on POD 8. For inpatient procedures, LPA peaked at 70% on POD 11, and MVPA peaked at 53% on POD 10. Adverse events in 2 patients were associated with a decline in activity.Conclusions
This study demonstrates that objective monitoring of postoperative physical activity using accelerometers is feasible in the pediatric surgical population. Recovery trajectories for inpatient and outpatient procedures differ. Accelerometer technology presents clinicians with a new potential tool for assessing and managing surgical recovery, and for determining if children are not recovering as expected.Type of study
Diagnostic Study.Level of evidence
III. 相似文献377.
Identification of a distinct low-affinity receptor for human interleukin-4 on pre-B cells 总被引:5,自引:0,他引:5
Fanslow WC; Spriggs MK; Rauch CT; Clifford KN; Macduff BM; Ziegler SF; Schooley KA; Mohler KM; March CJ; Armitage RJ 《Blood》1993,81(11):2998-3005
Biotinylated interleukin-4 (IL-4) was used to examine IL-4 receptor (IL- 4R) expression on a range of human B-cell lines by flow cytometry. Using high concentrations of biotinylated IL-4, we have identified a novel low-affinity IL-4 receptor expressed at high levels on pre-B lines. Expression of this low-affinity receptor did not correlate with detected mRNA levels for the previously cloned receptor or with reactivity of two anti-human IL-4R monoclonal antibodies (MoAb). Radiolabeled IL-4 cross-linking studies using pre-B lines showed a doublet of 65 to 75 Kd in contrast to the 110- to 130-Kd molecule detected on cells expressing the cloned IL-4R. A soluble IL-4 binding protein (IL-4bp) was purified from the supernatants of three pre-B lines expressing the low-affinity receptor on their surface. IL-4bp could block both IL-4-mediated CD23 induction on tonsil B cells and IL- 4-induced inhibition of proliferation of the pre-B line JM1. Partial N- terminal amino acid sequence was obtained from purified IL-4bp that confirmed this protein to be novel. A 12 amino acid peptide based on the IL-4bp sequence was used to produce a polyclonal antiserum that was reactive with purified IL-4bp, and also bound to the surface of pre-B cells but not to murine CTLL cells transfected with the human IL-4R. Blocking MoAb against the previously characterized high-affinity receptor inhibited IL-4-mediated proliferation of hIL-4R+ CTLL cells but had no effect on IL-4-induced inhibition of JM1 cell proliferation, and only partially inhibited IL-4-mediated CD23 and sIgM induction and proliferation of tonsil B cells. The data presented here provide evidence for a novel cell-surface expressed low-affinity IL-4R that also exists as a biologically active soluble IL-4 binding protein. 相似文献
378.
Maxwell PH; Ferguson DJ; Osmond MK; Pugh CW; Heryet A; Doe BG; Johnson MH; Ratcliffe PJ 《Blood》1994,84(6):1823-1830
We have obtained transgenic mice in which an erythropoietin-SV40 virus T antigen fusion gene is homologously recombined into the native Epo locus. This gene is expressed in a tissue-specific manner closely resembling that of the native Epo gene. Immunohistochemical detection of SV40 T antigen has been used to characterize the hepatic cell populations expressing the transgene. In mice stimulated by anaemia or hypobaric hypoxia, SV40 T antigen was demonstrated in two liver cell populations: a subset of hepatocytes and a nonparenchymal cell type. Immunohistochemical and ultrastructural characterization of these cells by light and electron microscopy showed the nonparenchymal cell type to be the Ito cells, which lie in a persinusoidal position within the space of Disse. We therefore conclude that Ito cells are the nonhepatocytic source of liver Epo production. These cells show many similarities to the Epo-producing fibroblastoid interstitial cells of the kidney. 相似文献
379.
Blast cells from 100 cases of acute leukemia were evaluated for the presence of methylthioadenosine phosphorylase (MTAase), an enzyme important in polyamine metabolism. Ten cases (10%) had undetectable levels of MTAase activity. Of the 10, 5 had acute lymphoblastic leukemia (ALL), 3 had acute myeloblastic leukemia (AML) and 2 expressed mixed lineage markers as determined by immunophenotyping. A relatively high frequency (38%) of MTAase deficiency was seen in ALL of T-cell origin. Nonmalignant hematopoietic cells from three patients with MTAase-deficient leukemias had readily detectable enzyme activity. Chromosomal abnormalities were detected in four of the seven MTAase- deficient cases in which karyotypic analysis was performed. No consistent karyotypic defect was apparent, and only one case displayed changes in chromosome 9, the putative location of the MTAase structural gene. The clinical findings among the enzyme-deficient cases were unremarkable except that all patients were male (P less than .01). Only one patient had "lymphomatous" features. We conclude that MTAase deficiency occurs in a wide variety of acute leukemias, that the lack of enzyme activity is specific to the malignant cells, and that an increased incidence occurs in ALL of T-cell origin. Furthermore, no specific gross chromosomal abnormality is associated with the enzyme deficiency. The marked male predominance in patients with MTAase- deficient acute leukemias suggests involvement of the X chromosome in the loss of enzyme activity. The absence of MTAase in some leukemias may be therapeutically exploitable. 相似文献
380.
JD COLLIER MK BENNETT MF BASSENDINE R. LENDRUM 《Journal of gastroenterology and hepatology》1995,10(4):396-400
pS2 is a 60 amino acid secretory polypeptide which belongs to a newly described family of trefoil-shaped growth factors. It is widely distributed throughout the gastrointestinal tract, particularly adjacent to damaged mucosa, and is also expressed by some epithelial tumours such as breast carcinoma. The aim of this study was to examine the expression of pS2 in pancreatic cancer. The presence of pS2 was analysed immunohistochemically using two antibodies, a polyclonal (pNR-2) and a monoclonal (pS2TM) in 42 cases of pancreatic adenocarcinoma and 10 cases of ampullary carcinoma. The findings were compared with chronic pancreatitis and normal pancreas. No immunostaining was seen in normal pancreas, with the exception of one area of ductular proliferation, and although 8/10 cases of chronic pancreatitis expressed pS2, it was focal and confined to the occasional duct. In contrast, a significant proportion of malignant cells in 23/42 (55%) of pancreatic adenocarcinoma and 8/10 (80%) of ampullary tumours expressed immunoreactive pS2. The finding of pS2 expression in more than 50% of pancreatic and ampullary carcinomas in contrast to the findings seen in chronic pancreatitis and normal pancreas suggests that pS2 may play an important role in the growth of these highly malignant tumours. 相似文献