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41.
Effect of gram-negative endotoxin on levels of serum corticosterone, TNF alpha, circulating blood cells, and the survival of rats 总被引:8,自引:0,他引:8
G Feuerstein J M Hallenbeck B Vanatta R Rabinovici P Y Perera S N Vogel 《Circulatory shock》1990,30(3):265-278
The relationship between serum tumor necrosis factor (TNF alpha), circulating blood cells, plasma corticosterone (CS), and survival was studied in conscious rats injected intravenously with E. coli lipopolysaccharide (LPS, 0.0001-28.8 mg/kg). The TNF alpha response was dose-related, peaked at 90-120 min after LPS injection, and subsided 6 hr later. The CS response showed an earlier onset, prolonged (greater than 12 hr) duration, and a broader dose-response pattern. White blood cells (WBC) and platelet depletion peaked at 2-4 and 24-48 hr post-LPS, respectively; however, no changes in the cell count were observed at LPS doses which produced greater than 50% maximal increase in TNF alpha levels. Survival curves for each of the LPS doses were significantly different from the doses of LPS which elicited TNF alpha release. Systemic injection of human recombinant TNF alpha (h-rTNF alpha), which produced plasma levels of TNF alpha 10 x 10(7) U/ml, much higher than the maximal TNF alpha levels produced by LPS, 1-2 x 10(5) U/ml, failed to affect survival, plasma WBC, or hematocrit. Our data suggest that factors other than TNF alpha produced by high doses of LPS are essential in eliciting LPS-induced death. 相似文献
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Seiji Yokoyama Pin-Yu Perera Thomas A. Waldmann Takachika Hiroi Liyanage P. Perera 《Journal of clinical immunology》2013,33(3):586-594
Celiac disease (CD) is an immune-mediated, inflammatory disorder of the small intestines with a defined genetic etiological component associated with the expression of HLA-DQ2 and/or HLA-DQ8 haplotypes. The dietary consumption of gluten-rich cereals triggers a gluten-specific immune response in genetically susceptible individuals leading to a spectrum of clinical manifestations ranging from an inapparent subclinical disease, to overt enteropathy that can in some individuals progress to enteropathy-associated T cell lymphoma (EATL). The tissue-destructive pathologic process of CD is driven by activated NK-like intraepithelial CD8+ lymphocytes and the proinflammatory cytokine IL-15 has emerged to be pivotal in orchestrating this perpetual tissue destruction and inflammation. Moreover, transgenic mice that over-express human IL-15 from an enterocyte-specific promoter (T3b-hIL-15 Tg) recapitulate many of the disease-defining T and B cell-mediated pathologic features of CD, further supporting the evolving consensus that IL-15 represents a valuable target in devising therapeutic interventions against the form of the disease that is especially refractory to gluten-free diet. In the present study, we evaluated the potential efficacy of tofacitinib, a pan-JAK inhibitor that abrogates IL-15 signaling, as a therapeutic modality against CD using T3b-hIL-15 Tg mice. We demonstrate that tofacitinib therapy leads to a lasting reversal of pathologic manifestations in the treated mice, thereby highlighting the potential value of tofacitininb as a therapeutic modality against refractory CD for which no effective therapy exists currently. Additionally, the visceral adiposity observed in the tofacitinib-treated mice underscores the importance of continued evaluation of the drug’s impact on the lipid metabolism. 相似文献
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Sajini Kuruppu Marvey Ghani Megan Pritchard Matthew Harris Ruwan Weerakkody Robert Stewart Gayan Perera 《European psychiatry》2021,64(1)
BackgroundPatients with depression are more susceptible to cardiovascular illness including vascular surgeries. However, health outcomes after vascular surgery among patients with depression is unknown. This study aimed to investigate associations of depression with post-operative health outcomes for vascular surgical patients.MethodsA retrospective observational study was conducted using data from a large mental healthcare provider and linked national hospitalization data for the same south London geographic catchment. OPCS-4 codes were used to identify vascular procedures. Health outcomes were compared between those with/without depression including length of hospital stay (LOS), inpatient mortality, and 30 day emergency hospital readmissions. Predictors of these health outcomes were also assessed.ResultsVascular surgery was received by 9,267 patients, including 446 diagnosed with depression. Patients with depression had a higher risk of emergency admission for vascular surgery (odds ratio [OR] 1.28; 1.03, 1.59), longer index LOS (IRR 1.38; 1.33–1.42), and a higher risk of 30-day emergency readmission (OR 1.82; 1.35–2.47). Patients with depression had higher inpatient mortality after adjustment for sociodemographic status (1.51; 1.03, 2.23) but not on full adjustment, and had longer emergency readmission LOS (1.13; 1.04, 1.22) after adjustment for sociodemographic factors and cardiovascular disease. Correlates of vascular surgery hospitalization among patients with depression included admission through emergency route for longer LOS, inpatient mortality, and 30-day hospital readmission.ConclusionPatients with depression undergoing vascular surgery have substantially poorer health outcomes. Screening for depression prior to surgery might be indicated to target preventative measures. 相似文献
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Ranawaka A. P. M. Perera Ronald Ko Owen T. Y. Tsang David S. C. Hui Mike Y. M. Kwan Christopher J. Brackman Esther M. W. To Hui-ling Yen Kathy Leung Samuel M. S. Cheng Kin Ho Chan Karl C. K. Chan Ka-Chi Li Linda Saif Vanessa R. Barrs Joseph T. Wu Thomas H. C. Sit Leo L. M. Poon Malik Peiris 《Journal of clinical microbiology》2021,59(2)
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Daniel L. Riddle Robert A. Perera William T. Nay Levent Dumenci 《Clinical orthopaedics and related research》2015,473(11):3527-3534
Background
Preoperative depressive symptoms have been shown in some but not all studies to be associated with poor self-reported pain and function outcomes. In addition, depressive symptoms after surgery have been shown to improve relative to preoperative levels.Questions/purposes
We hypothesized that (1) preoperative depressive symptoms would predict postoperative pain; (2) depressive symptoms would decrease after surgery; and (3) preoperative depressive symptoms would increase as the scheduled surgery date approached.Methods
Data from the Osteoarthritis Initiative, a National Institutes of Health-funded prospective multiyear cohort study, were used in this retrospective analysis. Persons from four communities were eligible if they had radiographic knee osteoarthritis or were at risk for developing knee osteoarthritis based on occupational, medical history, or body weight risk factors. A total of 4796 persons participated and rates of followup were 80% or greater over the course of the study. Participants completed a validated depressive symptom scale and the Knee Injury and Osteoarthritis Outcome Scale pain scale each year for 3 years before and 3 years after TKA. Latent growth curve modeling was used to model intercepts and slopes of pre- and postoperative depression and pain. Preoperative trajectories and intercepts were then used to predict postoperative pain and depressive symptoms adjusting for confounding variables.Results
After adjustment for potential confounding, we found no evidence that preoperative depressive symptoms predicted postoperative pain with function (estimate, 0.1; 95% confidence interval, −0.31 to 0.50; p = 0.64) or that depressive symptoms were reduced after surgery (z = 0.06, p = 0.80). We also found no evidence to indicate that preoperative depressive symptoms increased as the date of surgery approached (linear slope = 0.28, SE = 0.19, p = 0.15).Conclusions
Preoperative and postoperative depressive symptoms in patients before and after TKA did not appreciably change over a 6-year perioperative period. Patient depressive symptoms were not reduced after surgery and did not appear to be related to less pain postoperatively. Our findings of no association between preoperative depressive symptom severity and postoperative pain and no reduction in postoperative depressive symptoms run counter to other available evidence, potentially attributable, in part, to a data collection process that occurred outside of orthopaedic surgeons’ offices. Future research is needed to more fully explore the potential role of social desirability, the concept that patients respond in a way that they think the researcher or clinician wants them to respond in lieu of responding in a way that truly reflects the patient’s status. Social desirability may influence a TKA patient’s pain and function outcome assessment.Level of Evidence
Level I, prognostic study. 相似文献47.
Difference in outcomes after antibody‐mediated rejection between abo‐incompatible and positive cross‐match transplantations
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Lionel Couzi Miriam Manook Ranmith Perera Olivia Shaw Zubir Ahmed Nicos Kessaris Anthony Dorling Nizam Mamode 《Transplant international》2015,28(10):1205-1215
Graft survival seems to be worse in positive cross‐match (HLAi) than in ABO‐incompatible (ABOi) transplantation. However, it is not entirely clear why these differences exist. Sixty‐nine ABOi, 27 HLAi and 10 combined ABOi+HLAi patients were included in this retrospective study, to determine whether the frequency, severity and the outcome of active antibody‐mediated rejection (AMR) were different. Five‐year death‐censored graft survival was better in ABOi than in HLAi and ABOi+HLAi patients (99%, 69% and 64%, respectively, P = 0.0002). Features of AMR were found in 38%, 95% and 100% of ABOi, HLAi and ABOi+HLAi patients that had a biopsy, respectively (P = 0.0001 and P = 0.001). After active AMR, a declining eGFR and graft loss were observed more frequently in HLAi and HLAi+ABOi than in ABOi patients. The poorer prognosis after AMR in HLAi and ABOi+HLAi transplantations was not explained by a higher severity of histological lesions or by a less aggressive treatment. In conclusion, ABOi transplantation offers better results than HLAi transplantation, partly because AMR occurs less frequently but also because outcome after AMR is distinctly better. HLAi and combined ABOi+HLAi transplantations appear to have the same outcome, suggesting there is no synergistic effect between anti‐A/B and anti‐HLA antibodies. 相似文献
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Elly Montrieux Wilmer H. Perera Marley García Louis Maes Paul Cos Lianet Monzote 《Parasitology research》2014,113(8):2925-2932
The search for new therapeutic agents from natural sources has been a constant for the treatment of diseases such as leishmaniasis. Herein, in vitro and in vivo pharmacological activities of pure major phenolic constituents (caffeic acid, chlorogenic acid, ferulic acid, quercetin, and rosmarinic acid) from Pluchea carolinensis against Leishmania amazonensis are presented. Pure compounds showed inhibitory activity against promastigotes (IC50?=?0.2–0.9 μg/mL) and intracellular amastigotes (IC50?=?1.3–2.9 μg/mL). Four of them were selected after testing against macrophages of BALB/c mice: caffeic acid, ferulic acid, quercetin, and rosmarinic acid, with selective indices of 11, 17, 10, and 20, respectively. Ferulic acid, rosmarinic acid, and caffeic acid controlled lesion size development and parasite burden in footpads from BALB/c experimentally infected mice, after five injections of compounds by intralesional route at 30 mg/kg every 4 days. Pure compounds from P. carolinensis demonstrated antileishmanial properties. 相似文献