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41.
The biggest challenge in the serological diagnosis of visceral leishmaniasis (VL) is to find a biomarker with a high specificity. This study was undertaken to identify novel Leishmania donovani antigens to solve the existing problem. The soluble L. donovani promastigote antigen was separated by SDS-PAGE, and a Western blot was probed with pooled sera of five subjects with confirmed VL before (n = 9 pools) and after (n = 9 pools) treatment and at the 6-month follow-up visit (n = 9 pools), healthy controls not from an area of endemicity (n = 9 pools), and healthy controls from an area of endemicity. The antibody response to the identified partially purified antigen was ascertained by an enzyme-linked immunosorbent assay (ELISA) with 70 sera from patients with parasitologically confirmed VL, 48 sera from healthy controls from an area where the disease is not endemic, 60 sera from healthy controls from an area of endemicity, and 42 sera from patients in different disease groups. The eluted protein was subjected to two-dimensional (2D) gel electrophoresis, Western blotted, and probed with sera from patients with confirmed VL and from healthy controls not from an area of endemicity. The antigenic protein was further characterized by matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry. The identified protein (BHUP2) corresponds to a cytochrome c-like synthesis protein of 37 kDa. ELISA results were 94% sensitive, whereas specificities with sera from healthy controls from an area of endemicity, healthy controls not from an area of endemicity, and disease controls were 98%, 100%, and 97%, respectively. The antigen identified via a proteomics-based approach has a strong potential for further development as a diagnostic tool for VL.  相似文献   
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Objective

The objective of this study was to summarize the literature regarding the effects of renin-angiotensin system blockade (RASB) using angiotensin-converting enzyme inhibitors (ACEis) or angiotensin receptor blockers (ARBs) on human abdominal aortic aneurysm (AAA) growth, rupture, and perioperative mortality.

Methods

We conducted a systematic review in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Our review protocol was registered at the International Prospective Register of Systematic Reviews (CRD42016054082). We searched the Cochrane Central Register of Controlled Trials database, MEDLINE, and Embase from inception to 2017 for studies examining the effects of ACEi or ARB treatment on AAA growth, rupture, or perioperative mortality. Review, abstraction, and quality assessment were conducted in duplicate, and a third author resolved discrepancies. We assessed study quality using the Cochrane and Newcastle-Ottawa scales. We used random-effects models to calculate pooled mean differences and odds ratios (ORs) with 95% confidence intervals (CIs). Heterogeneity was quantified using the I2 statistic.

Results

Our search yielded 525 articles. One randomized and seven observational studies involving 35,448 patients were included. Inter-rater agreement was excellent (κ = 0.78), and risk of bias was low to moderate. All studies investigated ACEis, three studies investigated ARBs, and two studies included a composite RASB group consisting of ACEi or ARB users. Five studies assessed AAA growth, two assessed rupture rate, and one reported 30-day mortality after elective open repair. There was no difference in AAA growth rate between RASB and control (mean difference, 0.03 mm/y; 95% CI, ?0.40 to 0.46; P = .88; I2 = 60%). No protective effect of RASB (OR, 0.92; 95% CI, 0.72, 1.16; P = .47; I2 = 90%) was demonstrated for AAA rupture. Finally, RASB increased 30-day mortality in patients undergoing elective open AAA repair (OR, 5; 95% CI, 1.4, 27) according to a single well-adjusted study.

Conclusions

RASB does not appear to affect AAA growth and rupture rate but increases elective perioperative mortality. The small number of heterogeneous, retrospective studies and limited long-term follow-up preclude a definitive dismissal of RASB as pharmacotherapy for AAA. Prospective, long-term data are needed to clarify the effect of RASB on AAA growth, rupture, and perioperative mortality.  相似文献   
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OBJECTIVES: We evaluated the effect of the St Jude Medical sutureless anastomotic connector on endothelium-dependent and -independent saphenous vein graft relaxation, as well as on clinical outcomes and graft patency in patients. METHODS: Human saphenous vein grafts were assigned to control or connector groups (loaded for 1 or 5 minutes; n = 18). Isometric dose-response curves to endothelium-dependent and -independent (sodium nitroprusside) vasodilators were constructed in saphenous vein grafts precontracted with phenylephrine. Thrombin-mediated vasorelaxation, an early determinant of saphenous vein graft failure, was also evaluated. Percent maximum relaxation was compared between groups. Patients in whom the St Jude Medical connector was employed underwent clinical follow-up, stress tests, and angiography 6 to 12 months postoperatively. RESULTS: A23187-induced endothelium-mediated relaxation, sodium nitroprusside-induced endothelium-independent relaxation, and thrombin-mediated vasorelaxation did not differ between control and connector saphenous vein grafts at either time point studied. Twenty-seven patients received St Jude Medical connectors. There was no hospital mortality; patients were followed for 679 +/- 241 days. There was 1 late death; the connector saphenous vein graft was patent at postmortem. All connector saphenous vein grafts were patent at follow-up angiography. Four grafts had stenoses (30%-60%), without symptoms or requirement for intervention. All hand-sewn saphenous vein grafts were also patent. CONCLUSIONS: The St Jude Medical connector does not impair endothelium-dependent vasorelaxation. In patients, patency of the connector saphenous vein grafts 6 to 12 months postoperatively was 100% but 22% of grafts had non-flow-limiting stenoses at or near the connector. Further long-term studies are required to confirm the safety of the St Jude Medical connector with regards to endothelial function and restenosis.  相似文献   
45.
Initiation of protein synthesis from a termination codon.   总被引:17,自引:3,他引:17       下载免费PDF全文
We show that the amber termination codon UAG can initiate protein synthesis in Escherichia coli. We mutated the initiation codon AUG of the chloramphenicol acetyltransferase (CAT) gene to UAG (CATam1) and translated mRNA derived from the mutant CAT gene in E. coli S-30 extracts. A full-length CAT polypeptide was synthesized in the presence of tRNA(fMetCUA), a mutant E. coli initiator tRNA which has a change in the anticodon sequence from CAU to CUA. Addition of purified E. coli glutaminyl-tRNA synthetase substantially stimulated synthesis of the CAT polypeptide. Thus, initiation of protein synthesis with UAG and tRNA(fMetCUA) most likely occurs with glutamine and not methionine. The UAG codon also initiates protein synthesis in vivo. To eliminate a weak secondary site of initiation from AUC, the fifth codon, we further mutagenized the CATam1 gene at codons 2 (GAG----GAC) and 5 (AUC----ACC). Transformation of E. coli with the resultant CATam1.2.5 gene yielded transformants that synthesized CAT polypeptide and were resistant to chloramphenicol only when they were also transformed with the mutant tRNA(fMetCUA) gene. Immunoblot analyses and assays for CAT enzyme activity in extracts from transformed cells indicate that initiation from UAG is efficient, 60-70% of that obtained from AUG. Initiation of protein synthesis from UAG using a mutant initiator tRNA allows tightly regulated expression of specific genes. This may be generally useful for overproduction in E. coli and other eubacteria of proteins which are toxic to these cells.  相似文献   
46.
Epithelioid hemangioendothelioma is a rare neoplasm of vascular endothelial origin. It can develop in any tissue, but it occurs primarily in the soft tissue, liver, and rarely in the lung. Pulmonary epithelioid hemangioendothelioma can present in the thorax in various manifestations. In the typical pulmonary forms, epithelioid hemangioendothelioma presents as either a solitary nodule, or more often as multiple, small nodules. Pulmonary epithelioid hemangioendothelioma involving the pleural space occurs in patients with disseminated disease [1, 2]. We present a case of primary pleural epithelioid hemangioendothelioma.  相似文献   
47.
Lower limb crush injury is a major source of mortality and morbidity in trauma patients. Complications, especially surgical site infections (SSIs) are a major source of financial burden to the institute and to the patient as it delays rehabilitation. As such, every possible attempt should be made to reduce any complications. We, thus, aimed to compare the outcomes in early vs delayed closure of lower extremity stumps in cases of lower limb crush injury requiring amputation, so as to achieve best possible outcome. A randomised controlled study was conducted in the Division of Trauma Surgery & Critical Care at Jai Prakash Narayan Apex Trauma Centre, All India Institute of Medical Sciences, New Delhi from 1 September 2018 to 30 June 2019 and included patients undergoing lower limb amputation below hip joint. Patients were randomised in two groups, in one group amputation stump was closed primarily, while in the second group delayed primary closure of stump was performed. We compared rate of SSI, length of hospital stay, and number of surgeries in both the groups. Fifty‐six patients with 63 amputation stumps were recruited in the study. Mean age of patients in the study was 34 years, of which about 95% patients were males. The most common mechanism of injury was road traffic injury in 66% of patients. Mean injury severity score was 12.28 and four patients had diabetes preoperatively. Total 63 extremities were randomised with 30 cases in group I and 33 cases in group II as per computer‐generated random number. Above knee amputations was commonest (57.14%) followed by below knee amputations (33.3%). Two patients died in the current study. In group I, In‐hospital infection was detected in 7 cases (23.3%) and in group II 9 cases (27.3%) had SSI during hospital admission (P > .05). Mean hospital stay in group I was 10.32 ± 7.68 days and in group II was 11 ± 8.17 days (P > .05). Road traffic injuries and train‐associated injuries are a major cause of lower limb crush injuries, leading to limb loss. Delayed primary closure of such wounds requires extra number of surgical interventions than primary closure. There is no difference in extra number of surgical interventions required in both the groups. Thus, primary closure can be safely performed in patients undergoing lower limb amputations following trauma, provided that a good lavage and wound debridement is performed.  相似文献   
48.
The objective of our study was to evaluate the role of splenic artery embolization (SAE) in the management of traumatic splenic injuries. From September 2008 to September 2010, a total of 67 patients underwent nonoperative management (NOM) for blunt splenic injuries. Twenty-two patients were excluded from the study because of associated significant other organ injuries. Twenty-five patients underwent SAE followed by NOM (group A) and 20 patients underwent standard NOM (group B). Improvement in clinical and laboratory parameters during hospital stay were compared between two groups using Chi-square test and Mann–Whitney test. SAE was always technically feasible. The mean length of the total hospital stay was lower in the group A patients (5.4 vs. 6.6 day, [P = 0.050]). There was significant increase in hemoglobin and hematocrit levels and systolic blood pressure (SBP) in group A patients after SAE, whereas in group B patients there was decrease in hemoglobin and hematocrit levels and only slight increase in SBP (pre- and early posttreatment relative change in hemoglobin [P = 0.002], hematocrit [P = 0.001], and SBP [P = 0.017]). Secondary splenectomy rate was lower in group A (4 % [1/25] vs. 15 % [3/20] [P = 0.309]). No procedure-related complications were encountered during the hospital stay and follow-up. Minor complications of pleural effusion, fever, pain, and insignificant splenic infarct noted in 9 (36 %) patients. SAE is a technically feasible, safe, and effective method in the management of splenic injuries. Use of SAE as an adjunct to NOM of splenic injuries results improvement in hemoglobin, hematocrit levels, and SBP. SAE also reduces secondary splenectomy rate and hospital stay.Keyword: Trauma, Splenic artery embolisation  相似文献   
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