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Mitra Samareh Fekri Mehdi Torabi Sara Azizi Shoul Moghaddameh Mirzaee 《The American journal of emergency medicine》2018,36(2):277-280
Background
Pulmonary hypertension (PH) is one of the most common complications of COPD (chronic obstructive pulmonary disease), but its severe form is uncommon. Various factors play an important role in the occurrence and severity of pulmonary hypertension in patients.Methods
This cross-sectional study was performed on patients with COPD referred to an emergency department over a one-year period. The tests—including complete blood count (CBC) and arterial blood gas (ABG), pulmonary functional test (PFT) and echocardiography—were performed for all patients to measure mPAP (mean pulmonary artery pressure), ejection fraction (EF) and body mass index (BMI). The prevalence of severe pulmonary hypertension and its associated factors were investigated in these patients.Results
A total of 1078 patients was included in the study, of whom 628 (58.3%) were male and 450 (41.7%) were female. The mean age of the patients undergoing the study was 70.1 ± 12.2. A total of 136 (13.7%) of them had mPAP (mm Hg) ≥ 40 mm Hg as severe pulmonary hypertension. Following multivariable analysis by using the backward conditional method, it was shown that seven variables had a significant correlation with severe PH.Conclusions
The results showed that there is an independent correlation between hypoxia, hypopnea and compensatory metabolic alkalosis, polycythemia, left ventricular dysfunction, emaciation, and cachectic with severe pulmonary hypertension. The prevalence of severe PH in these patients was 13.7%. 相似文献4.
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In this report, a green synthesis of N-sulfonyl amidines via the direct reaction of tertiary or secondary amines with sulfonyl azides is described. Transition metal- and catalyst-free conditions were used for the synthesis of biologically important N-sulfonyl amidines. Further studies showed that the reaction proceeded via in situ aerobic oxidation of amines under reflux conditions.A green synthesis of N-sulfonyl amidines via the direct reaction of tertiary or secondary amines with sulfonyl azides. 相似文献
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Background Acute myocardial infarction (AMI) is a common cause of heart failure (HF), which can develop soon after AMI and may persist or resolve or develop late. HF after an MI is a major source of mortality. The cumulative incidence, prevalence and resolution of HF after MI in different age groups are poorly described. This study describes the natural history of HF after AMI according to age. Methods Patients with AMI during 1998 were identified from hospital records. HF was defined as treatment of symptoms and signs of HF with loop diuretics and was considered to have resolved if loop diuretic therapy could be stopped without recurrence of symptoms. Patients were cate- gorised into those aged 〈 65 years, 65-75 years, and 〉 75 years. Results Of 896 patients, 311,297 and 288 were aged 〈 65, 65-75 and 〉75 years and of whom 24%, 57% and 82% had died respectively by December 2005. Of these deaths, 24 (8%), 68 (23%) and 107 (37%) oc- curred during the index admission, many associated with acute HF. A further 37 (12%), 63 (21%) and 82 (29%) developed HF that persisted until discharge, of whom 15, 44 and 62 subsequently died. After discharge, 53 (24%), 55 (40%) and 37 (47%) patients developed I-IF for the first time, of whom 26%, 62% and 76% subsequently died. Death was preceded by the development of HF in 35 (70%), 93 (91%) and 107 (85%) in aged 〈 65 years, 65-75 years and 〉75 years, respectively. Conclusions The risk of developing HF and of dying after an MI in- creases progressively with age. Regardless of age, most deaths after a MI are preceded by the development of HF. 相似文献
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V. Villani K. Yamada J. R. Scalea B. C. Gillon J. S. Arn M. Sekijima M. Tasaki T. A. Cormack S. G. Moran R. Torabi A. Shimizu D. H. Sachs 《American journal of transplantation》2016,16(1):317-324
Our recent studies in an inbred swine model demonstrated that both peripheral and intra‐graft regulatory cells were required for the adoptive transfer of tolerance to a second, naïve donor‐matched kidney. Here, we have asked whether both peripheral and intra‐graft regulatory elements are required for adoptive transfer of tolerance when only a long‐term tolerant (LTT) kidney is transplanted. Nine highly‐inbred swine underwent a tolerance‐inducing regimen to prepare LTT kidney grafts which were then transplanted to histocompatible recipients, with or without the peripheral cell populations required for adoptive transfer of tolerance to a naïve kidney. In contrast to our previous studies, tolerance of the LTT kidney transplants alone was achieved without transfer of additional peripheral cells and without strategies to increase the number/potency of regulatory T cells in the donor. This tolerance was systemic, since most subsequent, donor‐matched challenge kidney grafts were accepted. These results confirm the presence of a potent tolerance‐inducing and/or tolerance‐maintaining cell population within LTT renal allografts. They suggest further that additional peripheral tolerance mechanisms, required for adoptive transfer of tolerance to a naïve donor‐matched kidney, depend on peripheral cells that, if not transferred with the LTT kidney, require time to develop in the adoptive host. 相似文献
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The anti-cytokeratin (CK) 8 monoclonal antibody (mab) TS1 has been shown to efficiently bind to CK8 expressed in carcinomas in vivo. The anti-idiotypic antibody of TS1, alphaTS1, can be used to regulate the tumor:non-tumor ratio of TS1 by clearing non-tumor binding TS1 from the circulation. If the interaction of TS1 to CK8 and alphaTS1 is fully understood, mutations can be used to improve the tumor:non-tumor ratio. A scFv was made of the mab TS1 and residues earlier identified by Erlandsson et al. as important for the interaction with both its antigen CK8 and its anti-idiotype alphaTS1, were mutated to alanine or amides and expressed in E. coli. The effects of the mutations were studied by ELISA and residues important for the interactions to both CK8 and alphaTS1 were identified as mainly tyrosines, charged residues, a serine and a tryptophan. Altogether, nine amino acid residues in TS1 were found to be important in the interaction to alphaTS1 and six residues for the interaction to CK8. Important residues, clustered together in the modelled protein, were identified as residues from CDR 3 of the heavy chain and the unexpected participation of a residue in CDR 2 of the light chain. Some of the important residues are likely to be hotspots. Hotspots constitute a few residues in an interaction that contribute most to the binding, energetically. Amino acid residues in hotspots often cluster together in the center of the interaction interface, but can also be spread out to the periphery. The hotspots are often surrounded by hydrophobic patches, which are seen in the modelled TS1 protein used in this study. Amino acid residues that increased the affinity when mutated were also identified for both interactions. These residues are likely to be located outside the interacting interface. It can from this study be concluded that it is wise to precede the mutational procedure with experiments that can give guidelines for the selection of which amino acid residues to mutate. If the guidelines from the chemical modifications from Erlandsson et al. not had been used, this study would have left some residues unmutated and thereby missed important information. 相似文献
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