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71.
Durairaj Ragu Varman Ganapathy Marimuthu Koilmani Emmanuvel Rajan 《Journal of neuroscience research》2013,91(3):426-435
Environmental enrichment (EE) has an influential role in reducing behavioral reactivity to stress. We previously observed that EE reduces the anxiety‐like behavior in the field mouse Mus booduga accompanied by a reduction in the expression of molecules involved in the stress pathway. In this study, we demonstrate the effect of different housing condition on regulation of micro‐RNA‐183‐SC35‐mediated splicing of acetylcholinesterase (AChE). Adult male M. booduga were captured from an agricultural field and housed under nonenriched standard conditions (SC) for 7 days and considered as directly from the wild (DW). On day 8, individuals were randomly assigned to three groups; DW, SC, and EE. The DW group's anxiety‐like behavior was assessed in the elevated plus maze (EPM) and open field test (OFT). The SC and EE groups were transferred to their respective conditions and housed for another 30 days. The mice housed in EE showed less anxiety‐like behavior on EPM and in OFT compared with DW and SC mice. Interestingly, miR‐183 expression was increased following exposure to EPM in EE mice but not in SC mice. Subsequently, the upregulated miR‐183 expression suppresses the SC35 expression and shifting of splicing from AChE‐S (synaptic) to AChE‐R (read‐through) form, whereas standard housing condition downregulate miR‐183 and induces the splicing of AChE. The upregulated AChE‐R form possibly terminates ACh transmission, which is reflected in the level of anxiety‐like behavior. Overall, the present study suggests that EE effectively regulates the miR‐183 pathway to reduce anxiety‐like behavior. © 2012 Wiley Periodicals, Inc. 相似文献
72.
Passive fit of a long-span screw-retained implant prosthesis is an important criteria for the success of the restoration. This article describes a technique for fabricating a ceramometal implant fixed dental prosthesis (FDP) for a long-span partially edentulous situation by altering the conventional screw-retained design. The possibility of a passive fit is maximized by intraoral luting of the cast frame to milled abutments, and the potential framework distortion during fabrication is compensated to a major extent. Retrievability is ensured by screw retention of the prosthesis to the implants. Compared with conventional porcelain fused to metal screw-retained FDP, this prosthesis is relatively inexpensive to fabricate. 相似文献
73.
74.
Altered Immunogenicity of Donor Lungs via Removal of Passenger Leukocytes Using Ex Vivo Lung Perfusion
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J. P. Stone W. R. Critchley T. Major G. Rajan I. Risnes H. Scott Q. Liao B. Wohlfart T. Sjöberg N. Yonan S. Steen J. E. Fildes 《American journal of transplantation》2016,16(1):33-43
Passenger leukocyte transfer from the donor lung to the recipient is intrinsically involved in acute rejection. Direct presentation of alloantigen expressed on donor leukocytes is recognized by recipient T cells, promoting acute cellular rejection. We utilized ex vivo lung perfusion (EVLP) to study passenger leukocyte migration from donor lungs into the recipient and to evaluate the effects of donor leukocyte depletion prior to transplantation. For this purpose, female pigs received male left lungs either following 3 h of EVLP or retrieved using standard protocols. Recipients were monitored for 24 h and sequential samples were collected. EVLP‐reduced donor leukocyte transfer into the recipient and migration to recipient lymph nodes was markedly reduced. Recipient T cell infiltration of the donor lung was significantly diminished via EVLP. Donor leukocyte removal during EVLP reduces direct allorecognition and T cell priming, diminishing recipient T cell infiltration, the hallmark of acute rejection. 相似文献
75.
Saini R Abd Razak NH Ab Rahman S Samsudin AR 《Journal (Canadian Dental Association)》2007,73(2):175-178
Chondrosarcomas are malignant tumours of cartilaginous origin. They range from a well-differentiated growth resembling a benign cartilage tumour to a high-grade malignancy with aggressive local behaviour and the potential to metastasize. Only 5% to 10% of chondrosarcomas are known to occur in the head and neck region. A case of chondrosarcoma of the anterior region of the mandible is presented, along with a review of the relevant literature. 相似文献
76.
McLean Andrew Mukherjee Ankur Phukan Chandan Veeratterapillay Rajan Soomro Naeem Somani Bhaskar Rai Bhavan Prasad 《Journal of robotic surgery》2020,14(1):1-9
Journal of Robotic Surgery - To systematically review world literature and compare peri-operative outcome including operating time (OT), estimated blood loss (EBL), warm ischemia time (WIT), length... 相似文献
77.
Rajan T. Gupta Kamil F. Faridi Abhay A. Singh Niccolò M. Passoni Kirema Garcia-Reyes John F. Madden Thomas J. Polascik 《Urologic oncology》2014,32(8):1292-1299
ObjectivesThe purpose of our study was to test our hypothesis that multiparametric magnetic resonance imaging (mpMRI) may have a higher prognostic accuracy than the Partin tables in predicting organ-confined (OC) prostate cancer and extracapsular extension (ECE) after radical prostatectomy (RP).Methods and materialsAfter institutional review board approval, we retrospectively reviewed 60 patients who underwent 3-T mpMRI before RP. mpMRI was used to assess clinical stage and the updated version of the Partin tables was used to calculate the probability of each patient to harbor OC disease. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of mpMRI in detecting OC and ECE were calculated. Logistic regression models predicting OC pathology were created using either clinical stage at mpMRI or Partin tables probability. The area under the curve was used to calculate the predictive accuracy of each model.ResultsMedian prostate-specific antigen level at diagnosis was 5 ng/ml (range: 4.1–6.7 ng/ml). Overall, 52 (86.7%) men had cT1 disease, 7 (11.7%) had cT2a/b, and 1 (1.6%) had cT3b at digital rectal examination. Biopsy Gleason score was 6, 3+4 = 7, 4+3 = 7, 8, and 9 to 10 in 28 (46.7%), 15 (25%), 3 (5%), 10 (16.7%), and 4 (6.6%) patients, respectively. At mpMRI, clinical stage was defined as cT2a/b, cT2c, cT3a, and cT3b in 11 (18.3%), 23 (38.3%), 21 (35%), and 5 (8.4%) patients, respectively. At final pathology, 38 men (63.3%) had OC disease, whereas 18 (30%) had ECE and 4 (6.7%) had seminal vesicle invasion.The sensitivity, specificity, PPV, and NPV of mpMRI in detecting OC disease were 81.6%, 86.4%, 91.2%, and 73.1%, respectively, whereas in detecting ECE were 77.8%, 83.4%, 66.7%, and 89.7%, respectively. At logistic regression, both the Partin tables–derived probability and the mpMRI clinical staging were significantly associated with OC disease (all P<0.01). The area under the curves of the model built using the Partin tables and that of the mpMRI model were 0.62 and 0.82, respectively (P = 0.04).ConclusionsThe predictive accuracy of mpMRI in predicting OC disease on pathological analysis is significantly greater than that of the Partin tables. mpMRI had a high PPV (91.2%) when predicting OC disease and a high NPV (89.7%) with regard to ECE. mpMRI should be considered when planning prostate cancer treatment in addition to readily available clinical parameters. 相似文献
78.
Senthilnathan Natarajan Venkatachalam Gopalan Raja Annamalai Arunjunai Rajan Chun-Ping Jen 《Materials》2021,14(7)
Tungsten heavy alloys are two-phase metal matrix composites that include W–Ni–Fe and W–Ni–Cu. The significant feature of these alloys is their ability to acquire both strength and ductility. In order to improve the mechanical properties of the basic alloy and to limit or avoid the need for post-processing techniques, other elements are doped with the alloy and performance studies are carried out. This work focuses on the developments through the years in improving the performance of the classical tungsten heavy alloy of W–Ni–Fe through doping of other elements. The influence of the percentage addition of rare earth elements of yttrium, lanthanum, and their oxides and refractory metals such as rhenium, tantalum, and molybdenum on the mechanical properties of the heavy alloy is critically analyzed. Based on the microstructural and property evaluation, the effects of adding the elements at various proportions are discussed. The addition of molybdenum and rhenium to the heavy alloy gives good strength and ductility. The oxides of yttrium, when added in a small quantity, help to reduce the tungsten’s grain size and obtain good tensile and compressive strengths at high temperatures. 相似文献
79.
Fiber Bragg grating (FBG)-based acoustic emission (AE) detection and monitoring is considered as a potential and emerging technology for structural health monitoring (SHM) applications. In this paper, an overview of the FBG-based AE monitoring system is presented, and various technologies and methods used for FBG AE interrogation systems are reviewed and discussed. Various commercial FBG AE sensing systems, SHM applications of FBG AE monitoring, and market potential and recent trends are also discussed. 相似文献
80.
OBJECTIVE: Evaluation of a complex and variable disease such as rheumatoid arthritis (RA) poses a challenge particularly over the medium to long term. A practical framework to evaluate clinically relevant outcomes over the long term is the "5D" approach of Fries, described in 1980. We describe the 20 year outcome in 52 survivors of a 123 patient cohort in terms of change in discomfort, disability, drug side effects, dollar costs, and deaths. METHODS: We studied 123 patients with RA allocated to their first disease modifying antirheumatic drug (DMARD) between 1977 and 1979. All were under the overall care of one physician over the 20 years and were maintained where possible taking a single DMARD. Baseline demographic variables, the Ritchie Articular Index (RAI), Lee functional index, and erythrocyte sedimentation rate (ESR) were initially recorded. The extent to which the demographic and disease variables contributed to need for joint replacement surgery was assessed. Therapies for comorbidity were also documented. RESULTS: At cohort inception mean age was 50 years, RAI was 35, and median disease duration 5.5 years. F:M ratio was 90:33; 96% of patients were positive for rheumatoid factor (RF). Initial median ESR was 55 mm/h. At 20 years, 9 patients (7% of original cohort, 14% of survivors) were lost to followup and 62 (50%) had died. In the 52 survivors RAI, a surrogate for disability, showed a significant improvement (p < 0.0001), but disability measured by Lee functional index showed a deterioration (p = 0.018); 50% underwent joint replacement surgery. Initial ESR and mean ESR over the first 10 years of followup were significantly higher in those who required surgery. Nonsteroidal antiinflammatory drug (NSAID) use declined, but at least 2 deaths and 4 renal deaths that may have been related to therapy were attributed to NSAID use. No unexpected DMARD toxicity or mortality occurred. Concomitant therapy for comorbidity, in particular for cardiovascular disease, osteoporosis, and gastrointestinal disease, increased: more than 60% were on these therapies at 20 year followup. CONCLUSION: Strategies to improve the outcome of RA in all dimensions should include: earlier referral for expert assessment; avoidance of NSAID gastrointestinal and nephrotoxicity; a more intensive effort to identify effective management of comorbidity and those likely to have a poor outcome. Such patients require sustained, intensive therapy to minimize later disability. 相似文献