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91.
Metabolic Brain Disease - Patients with liver disease often have alteration of neurological status which requires admission to an intensive care unit. Patients with acute liver failure (ALF),...  相似文献   
92.
Phosphocholine (PC), an immunodominant molecule present on a wide range of organisms, including filariae, evokes antibody responses that lead to false-positive reactions in routine serological assays. Humans essentially do not respond to PC in the IgG4 subclass; therefore, by configuring an enzyme immunoassay to assess antibodies of the IgG4 subclass only, we were able to eliminate serological false-positive results in 32 of 34 cross-reactive sera from patients with non-filarial parasitic infections. Specificity was thus greatly enhanced with minimal loss of sensitivity. Because preadsorption of these cross-reactive sera to remove antibodies to PC eliminated only approximately 50% of the original cross-reactivity, other shared epitopes (perhaps similar to PC) are also likely to be restricted by IgG subclass.  相似文献   
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94.
The growing problem of antibiotic resistant bacteria, along with a dearth of new antibiotics, has redirected attention to the search for alternative antimicrobial agents. Conjugated oligoelectrolytes (COEs) are an emerging class of antimicrobial agents which insert into bacterial cell membranes and are inhibitory against a range of Gram-positive and Gram-negative bacteria. In this study, the extent of COE resistance that Enterococcus faecalis could achieve was studied. Enterococci are able to grow in hostile environments and develop resistance to membrane targeting antibiotics such as daptomycin in clinical settings. Herein we expand our knowledge of the antimicrobial mechanism of action of COEs by developing COE-resistant strains of E. faecalis OG1RF. Evolution studies yielded strains with a moderate 4–16 fold increase in antimicrobial resistance relative to the wild type. The resistant isolates accumulated agent-specific mutations associated with the liaFSR operon, which is a cell envelope-associated stress-response sensing and regulating system. The COE resistant isolates displayed significantly altered membrane fatty acid composition. Subsequent, exogenous supplementation with single fatty acids, which were chosen based on those dominating the fatty acid profiles of the mutants, increased resistance of the wild-type E. faecalis to COEs. In combination, genetic, fatty acid, and uptake studies support the hypothesis that COEs function through insertion into and disruption of membranes and that the mechanism by which this occurs is specific to the disrupting agent. These results were validated by a series of biophysical experiments showing the tendency of COEs to accumulate in and perturb adapted membrane extracts. Collectively, the data support that COEs are promising antimicrobial agents for targeting E. faecalis, and that there is a high barrier to the emergence of severely resistant strains constrained by biological limits of membrane remodeling that can occur in E. faecalis.

COEs are emerging antimicrobials to combat drug resistant infections and to which bacteria develop only limited resistance.  相似文献   
95.
96.
Artificial intelligence (AI) demonstrated by machines is based on reinforcement learning and revolves around the usage of algorithms. The purpose of this review was to summarize concepts, the scope, applications, and limitations in major gastrointestinal surgery. This is a narrative review of the available literature on the key capabilities of AI to help anesthesiologists, surgeons, and other physicians to understand and critically evaluate ongoing and new AI applications in perioperative management. AI uses available databases called “big data” to formulate an algorithm. Analysis of other data based on these algorithms can help in early diagnosis, accurate risk assessment, intraoperative management, automated drug delivery, predicting anesthesia and surgical complications and postoperative outcomes and can thus lead to effective perioperative management as well as to reduce the cost of treatment. Perioperative physicians, anesthesiologists, and surgeons are well-positioned to help integrate AI into modern surgical practice. We all need to partner and collaborate with data scientists to collect and analyze data across all phases of perioperative care to provide clinical scenarios and context. Careful implementation and use of AI along with real-time human interpretation will revolutionize perioperative care, and is the way forward in future perioperative management of major surgery.  相似文献   
97.
AimsWe sought to characterize the direction and associated factors of eGFR change following diagnosis of youth-onset type 1 and type 2 diabetes.MethodsWe assessed the direction of eGFR change at two visits (mean 6.6 years apart) in SEARCH, a longitudinal cohort study of youth-onset type 1 and type 2 diabetes. We used the CKiDCr-CysC equation to estimate GFR and categorized ‘rising’ and ‘declining’ eGFR as an annual change of ≥3 ml/min/1.73 m2 in either direction. Multivariable logistic regression evaluated factors associated with directional change in eGFR.ResultsEstimated GFR declined in 23.8% and rose in 2.8% of participants with type 1 diabetes (N = 1225; baseline age 11.4 years), and declined in 18.1% and rose in 15.6% of participants with type 2 diabetes (N = 160; baseline age 15.0 years). Factors associated with rising and declining eGFR (versus stable) in both type 1 and type 2 diabetes included sex, age at diagnosis, baseline eGFR and difference in fasting glucose between study visits. Additional factors in type 1 diabetes included time from baseline visit, HbA1c and body mass index.ConclusionsOver the first decade of diabetes, eGFR decline is more common in type 1 diabetes whereas eGFR rise is more common in type 2 diabetes.  相似文献   
98.
In the Indian state of Bihar, the sensitivities and specificities of direct agglutination tests (DAT) and rK39 test strips for the detection of Leishmania donovani infection in humans were explored and found to be generally good (92%-100%). When 172 asymptomatic individuals [16 'case-contacts' who lived in the same households as past or current, confirmed cases of visceral leishmaniasis (VL) and 156 other subjects from neighbouring households] were tested, the same 36 (21%) individuals, including all 16 'case-contacts', were found seropositive using each type of test. When followed-up after 3 months, 18 of the individuals who had been found seropositive in the baseline survey remained seropositive, and eight (44%) of these had developed symptomatic VL, with amastigotes in their splenic aspirates. Seven (44%) of the 16 'case-contacts' but only one (5%) of the other 20 subjects found seropositive at baseline went on to develop VL within 3 months. Although the strip test appeared slightly better than DAT for predicting the development of VL in the 172 subjects, either type of test may be very useful for the early detection of asymptomatic L. donovani infection and thus the identification of those at relatively high risk of developing VL.  相似文献   
99.

Purpose

Visceral leishmaniasis (VL), a protozoan disease, is 100 % fatal if left untreated. Anemia is common in VL which plays a role in expression of clinically overt VL disease. Laboratory clues are scarce for strengthening clinical suspicion for severity in VL. Hypertriglyceridemia has emerged as a new concept for the diagnosis and prognosis in VL. The present study is aimed at correlating the magnitude of hypertriglyceridemia with the severity in VL.

Materials and methods

A retrospective case–control study was conducted between January 2012 to December 2013 among 124 patients coming for treatment from VL endemic areas, who had fever of more than 15 days and did not respond to antimalarials and antibiotics. The parasitologically confirmed VL cases (n = 87) were categorized as mild/moderate (n = 60) and severe (n = 27) groups according to WHO classification for anemia and parasite burden. Serum triglycerides were assayed in VL groups along with controls (n = 37).

Results

Serum triglyceride level was significantly higher in VL than controls [mean values were 173.50 ± 47.67 versus 127.1 ± 53.79 mg/dl, respectively (p < 0.0001)]. Triglyceride level was significantly higher in severe than in mild/moderate group of VL [211.3 ± 50.2 mg/dl versus 134 ± 45.09 mg/dl, respectively (p < 0.0001)]. Hypertriglyceridemia (>161.7 mg/dl) was noted in all severe VL patients, compared to 31.66 % of mild or moderate group (p < 0.0001). There was no significant difference between mild/moderate VL and controls.

Conclusions

It is hypothesized that hypertriglyceridemia could be of additional diagnostic benefit to assess the probability and severity of VL in endemic areas.
  相似文献   
100.
Platelets and their granular contents influence both angiogenesis and breast cancer progression. This study was performed to assess the effect of breast cancer and its treatment on platelet biology and the response to inhibition of the platelet P2Y12 receptor. Receptor-specific platelet activation and inhibition was studied for three platelet-associated proteins important in cancer angiogenesis and progression, vascular endothelial growth factor (VEGF), thrombospondin1 (TSP1), and transforming growth factor beta 1 (TGF-β1).

Twenty-four women with active breast cancer and 10 healthy controls not receiving antiplatelet therapy participated in the study. Ex vivo activation of platelets in whole blood was accomplished using PAR1AP, PAR4AP, convulxin, and ADP. Platelet inhibition was accomplished using the P2Y12 receptor antagonist cangrelor (the in vitro equivalent of clopidogrel). VEGF, TSP1, and TGF-β1 were measured using standard ELISA.

Platelet activation by ADP, PAR1, PAR4, and collagen receptors increased VEGF, TSP1, and TGF-β1 secretion in patients with breast cancer. Agonist-induced release of VEGF was greater in cancer patients as compared to healthy controls (p = 0.02 for ADP, p < 0.001 for PAR1AP, PAR4AP, and convulxin) despite a decrease in the efficiency of VEGF secretion in patients with breast cancer. These differences were not observed for TSP1 and TGF-β1 secretion. P2Y12 receptor inhibition decreased VEGF, TSP1, and TGF-β1 secretion. In patients with cancer, cangrelor inhibited TSP1 release to a greater extent than VEGF and TGF-β1 release. In patients with breast cancer, the magnitude of platelet inhibition achieved by cangrelor was greater than that achieved with healthy controls for all agonists and platelet proteins studied.

While platelets are known to influence progression of breast cancer, our results show that breast cancer and its treatment influence the platelet phenotype by increasing the secretion of pro-angiogenic proteins following platelet activation, modulating the efficiency of platelet protein release as well as increasing the response to antiplatelet therapy.  相似文献   

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