Computer Evaluation of Overhead Equipment for Electric Railroad Traction

The mathematical models and associated computer programs for analyzing a number of designs of overhead equipment such as simple catenary, compound catenary, stitched catenary, tunel equipment, and single-wire system, together with many possible variations are described. The programs are able to deal with up to four pantographs, and the initial conditions assumed are that the wires have their static equilibrium configurations and that the front pantograph is at the beginning of the first span touching the contact wire (or trolley wire) and moving tangentially to it. Any subsequent pantographs reach the beginning of the equipment after the start of the run and are then dealt with appropriately. The output of the programs list the input data, the total percentage contact loss between the panhead and contact wire in each span and the pantograph heights and contact forces at appropriate intervals of time. Graph plots of the pantograph heights and contact forces are also produced. The results of these programs are shown to give satisfactory agreement with previously published results obtained on a scaled model.     

ADP-ribosylation factor and phosphatidic acid levels in Golgi membranes during budding of coatomer-coated vesicles

The finding that ADP-ribosylation factor (ARF) can activate phospholipase D has led to debate as to whether ARF recruits coat proteins through direct binding or indirectly by catalytically increasing phosphatidic acid production. Here we test critical aspects of these hypotheses. We find that Golgi membrane phosphatidic acid levels do not rise-in fact they decline-during cell-free budding reactions. We confirm that the level of membrane-bound ARF can be substantially reduced without compromising coat assembly [Ktistakis, N. T., Brown, H. A., Waters, M. G., Sternweis, P. C. & Roth, M. G. (1996) J. Cell Biol. 134, 295-306], but find that under all conditions, ARF is present on the Golgi membrane in molar excess over bound coatomer. These results do not support the possibility that the activation of coat assembly by ARF is purely catalytic, and they are consistent with ARF forming direct interactions with coatomer. We suggest that ARF, like many other G proteins, is a multifunctional protein with roles in trafficking and phospholipid signaling.     

Reprogramming of early embryonic blastomeres into endodermal progenitors by a Caenorhabditis elegans GATA factor

The END-1 GATA factor has been implicated in specifying endoderm in Caenorhabditis elegans and is the earliest known zygotic protein expressed in the lineage of E, the clonal endoderm progenitor. We report that ubiquitous end-1 expression during a critical period in embryogenesis causes all non-endodermal lineages to produce endoderm instead of ectoderm and/or mesoderm. END-1 expression bypasses the requirement for maternal SKN-1 and the maternal Wnt signaling pathway in endoderm formation. This suggests that a primary function of these maternal factors is to regulate zygotic end-1 expression, which is then sufficient to initiate the entire program for endoderm development.     

Cemented versus cementless total hip arthroplasty. A comparative study of equivalent patient populations

Seventy-one cemented total hip arthroplasties (THAs) in 66 patients were compared with 70 cementless THAs in 61 patients. The cemented and cementless components were identical except for the presence of a porous proximal surface on the cementless component. The mean follow-up time was 4.3 years in the cemented group and 4.1 years in the cementless group, with a minimum follow-up of two years. Postoperative Charnley pain scores were identical for both groups, as was the incidence of limp. The final Charnley function score, however was significantly higher in the cementless group (5.6) than in the cemented group (5.1). One revision was performed in the cemented group, none in the cementless group. Complete demarcation of the bone-cement interface was presented in two cemented components and was associated with subsidence. Three cementless components had early subsidence, and two of these had complete radiopaque lines around the porous surface. None of these three patients, however, had unsatisfactory pain or function scores. The most important finding of this study is the equivalence of clinical results noted in both cemented and cementless THA as late as six years after operation.     

Incidence of pulmonary embolism after total knee arthroplasty with low-dose coumadin prophylaxis

The incidence of pulmonary embolism (PE) in osteoarthritic patients prophylaxed with low-dose coumadin after cemented total knee arthroplasty (TKA) was investigated prospectively. Each patient had a preoperative perfusion scan and a ventilation-perfusion scan on the seventh postoperative day. Pulmonary embolism was diagnosed by a high probability ventilation-perfusion scan or positive arteriogram. Patients with a moderate probability scan had an arteriogram to rule out PE. Pulmonary embolus was identified in 48 (5.6%) of 852 TKAs in 755 patients. Of these, six (0.7%) were symptomatic, and no fatal PE was identified. Age, gender, and weight did not show statistical differences comparing the PE and non-PE groups, nor did the incidences of previous PE, contralateral phlebitis, malignancy, and diabetes. A history of ipsilateral phlebitis increased the risk of PE from 5.2% to 13%, and a history of cardiac disease decreased the risk from 7.8% to 4.2%. Type of anesthesia, blood loss, tourniquet time, and prosthesis type were not significant factors. With the exception of previous contralateral phlebitis, traditional risk factors for PE were not found to increase risk of PE with low-dose coumadin prophylaxis. Spinal anesthesia that has been shown to be protective in total hip surgery was not a significant factor in this study.     

Inhibition of migration of neural crest-derived cells by the abnormal mesenchyme of the presumptive aganglionic bowel of ls/ls mice: analysis with aggregation and interspecies chimeras

The terminal bowel is congenitally aganglionic in ls/ls mice. The condition has been associated with an overabundance of laminin and other matrix molecules. Aggregation ls/ls<==>C3H chimeric mice and interspecies mouse<==>quail chimeras were constructed to test the hypothesis that the aganglionosis arises because the ls/ls gut and not the neural crest is abnormal. Demonstration of beta-glucuronidase activity permitted genotypically ls/ls and C3H cells to be distinguished in the ls/ls<==>C3H chimeras. Aganglionosis did not occur in the ls/ls<==>C3H mice and ls/ls neurons were observed in the terminal bowel. Following bactransplantation of control segments of mouse gut into quail host embryos, mouse cells migrated to host targets normally colonized by cells from the neural crest; moreover, quail crest-derived cells entered the mouse gut. In contrast, cells did not migrate to these targets from presumptive aganglionic ls/ls bowel and quail crest-derived cells neither entered the ls/ls gut nor migrated through it. Laminin immunoreactivity was present in the backgrafts of murine colon and was far more abundant and widespread in those from ls/ls than in those from control animals. These data suggest that the presumptive aganglionic ls/ls bowel does not contain crest-derived cells because these cells, which are normal in ls/ls mice, do not enter it. This failure of colonization may be related to the premature formation of neurons outside the abnormal gut, a response that may be promoted by the excessive secretion of laminin by the ls/ls enteric mesenchyme.     

Effect of dopamine receptor antagonists on cocaine subjective effects: a naturalistic case study

Schizophrenic patients on neuroleptic medications abuse cocaine and report cocaine-induced euphoria. This study was undertaken to provide better clinical characterization of these phenomena by administering the POMS and a custom-designed questionnaire. A group of heavy cocaine users who were not mentally ill served as the control group. The results clearly suggest that schizophrenic patients report cocaine-induced euphoria and post-use craving despite being treated with therapeutic doses of haloperidol or fluphenazine. The responses of the control group were similar to that of the schizophrenic group except that the latter subjects reported a greater degree of anxiety. These results suggest that blockade of D2 receptors is not sufficient to block cocaine-induced subjective effects in humans.     

The BCL-6 proto-oncogene controls germinal-centre formation and Th2-type inflammation

The incidence of nosocomial enterococcal infection has increased steadily over the past two decades. The treatment of patients with enterococcal infection has been complicated by the emergence of strains possessing high level resistance to aminoglycosides, penicillins and, most recently, glycopeptides. Several recent studies have evaluated alternative antimicrobial agents for use against strains resistant to some or all standard agents. In this report, we review the therapeutic options for the management of antibiotic-resistant enterococcal infection.     

Bacteria in the prostate tissue of men with idiopathic prostatic inflammation

PURPOSE: Although antibiotics represent the first line of treatment for prostatitis syndromes, physicians can document infection in remarkably few cases. We examined the relationship of genitourinary infection to inflammatory prostatitis in 85 subjects without bacteriuria. MATERIALS AND METHODS: Evaluation consisted of cultures of urethra, urine and transperineal prostate biopsies, specifically for commensal and fastidious organisms, and leukocyte counts of expressed prostatic secretions. RESULTS: Men with inflamed expressed prostatic secretions (25) were more likely to have any bacterial isolation (p = 0.01), positive cultures for anaerobic bacteria (p = 0.03), higher total bacterial counts (p = 0.02) and more bacteria, species isolated (p = 0.02) in prostate biopsy cultures than men without expressed prostatic secretion inflammation (60). CONCLUSIONS: Bacterial colonization/invasion of the prostate may be associated with inflammatory prostatitis in some cases.     

Can the Randomized Controlled Trial Literature Generalize to Nonrandomized Patients?

To determine the extent to which published randomized controlled trials (RCTs) of psychotherapy can be generalized to a sample of outpatients, the authors matched information obtained from charts of patients who had been screened out of RCTs to inclusion and exclusion criteria from published RCT studies. Most of the patients in the sample who had primary diagnoses represented in the RCT literature were judged eligible for at least 1 RCT. However, many patients in the sample with substance use disorders or social anxiety disorder were not eligible for at least 2 RCTs. Common reasons that patients did not match with at least 2 published RCTs for psychotherapy included (a) patients were in partial remission, (b) patients failed to meet minimum severity or duration criteria, (c) patients were being treated with antidepressant medication, and (d) the disorder being studied was not primary (mostly for social anxiety patients). The implications of these findings for future research and clinical practice are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)