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41.
C4d in Acute Rejection After Liver Transplantation—A Valuable Tool in Differential Diagnosis to Hepatitis C Recurrence 总被引:1,自引:0,他引:1
M. Schmeding A. Dankof V. Krenn M.G. Krukemeyer M. Koch A. Spinelli J.M. Langrehr U.P. Neumann P. Neuhaus 《American journal of transplantation》2006,6(3):523-530
Hepatitis C is the most common indication for liver transplantation. Recurrence of HCV is universal leading to graft failure in up to 40% of all patients. The differentiation between acute rejection and recurrent hepatitis C is crucial as rejection treatments are likely to aggravate HCV recurrence. Histological examination of liver biopsy remains the gold standard for diagnosis of acute rejection but has failed in the past to distinguish between acute rejection and recurrent hepatitis C. We have recently reported that C4d as a marker of the activated complement cascade is detectable in hepatic specimen in acute rejection after liver transplantation. In this study, we investigate whether C4d may serve as a specific marker for differential diagnosis in hepatitis C reinfection cases. Immunohistochemical analysis of 97 patients was performed. A total of 67.7% of patients with acute cellular rejection displayed C4d-positive staining in liver biopsy whereas 11.8% of patients with hepatitis C reinfection tested positive for C4d. In the control group, 6.9% showed C4d positivity. For the first time we were able to clearly demonstrate that humoral components, represented by C4d deposition, play a role in acute cellular rejection after LTX. Consequently C4d may be helpful to distinguish between acute rejection and reinfection after LTX for HCV. 相似文献
42.
Hakim Echchannaoui Stephen L Leib Ulf Neumann Regine MA Landmann 《BMC infectious diseases》2007,7(1):25
Background
Streptococcus (S.) pneumoniae meningitis has a high lethality despite antibiotic treatment. Inflammation is a major pathogenetic factor, which is unresponsive to antibiotics. Therefore adjunctive therapies with antiinflammatory compounds have been developed. TNF484 is a TNF-alpha converting enzyme (TACE) inhibitor and has been found efficacious in experimental meningitis. Toll-like receptor 2 (TLR2) contributes to host response in pneumococcal meningitis by enhancing bacterial clearing and downmodulating inflammation. In this study, TNF484 was applied in mice, which lacked TLR2 and exhibited a strong meningeal inflammation. 相似文献43.
Anke Sambeth Minna Huotilainen Elena Kushnerenko Vineta Fellman Elina Pihko 《Clinical neurophysiology》2006,117(3):496-503
OBJECTIVE: We investigated whether newborns respond differently to novel and deviant sounds during quiet sleep. METHODS: Twelve healthy neonates were presented with a three-stimulus oddball paradigm, consisting of frequent standard (76%), infrequent deviant (12%), and infrequent novel stimuli (12%). The standards and deviants were counterbalanced between the newborns and consisted of 500 and 750 Hz tones with two upper harmonics. The novel stimuli contained animal, human, and mechanical sounds. All stimuli had a duration of 300 ms and the stimulus onset asynchrony was 1s. Evoked magnetic responses during quiet sleep were recorded and averaged offline. RESULTS: Two deflections peaking at 345 and 615 ms after stimulus onset were observed in the evoked responses of most of the newborns. The first deflection was larger to novel and deviant stimuli than to the standard and, furthermore, larger to novel than to deviant stimuli. The second deflection was larger to novel and deviant stimuli than to standards, but did not differ between the novels and deviants. CONCLUSIONS: The two deflections found in the present study reflect different mechanisms of auditory change detection and discriminative processes. SIGNIFICANCE: The early brain indicators of novelty detection may be crucial in assessing the normal and abnormal cortical function in newborns. Further, studying evoked magnetic fields to complex auditory stimulation in healthy newborns is needed for studying the newborns at-risk for cognitive or language problems. 相似文献
44.
Reduction of scar formation in full-thickness wounds with topical celecoxib treatment 总被引:4,自引:0,他引:4
Traci A. Wilgus PhD ; Yael Vodovotz PhD ; Elena Vittadini PhD ; Elizabeth A. Clubbs BS ; Tatiana M. Oberyszyn PhD 《Wound repair and regeneration》2003,11(1):25-34
Adult wound repair occurs with an initial inflammatory response, reepithelialization, and the formation of a permanent scar. Although the inflammatory phase is often considered a necessity for successful adult wound healing, fetal healing studies have shown the ability to regenerate skin and to heal wounds in a scarless manner in the absence of inflammation. The cyclooxygenase-2 (COX-2) enzyme, a known mediator of inflammation, has been shown to contribute to a variety of inflammatory conditions and to the development of cancer in many organs. To examine the role of COX-2 in the wound healing process, incisional wounds were treated topically with the anti-inflammatory COX-2 inhibitor celecoxib. Acutely, celecoxib inhibited several parameters of inflammation in the wound site. This decrease in the early inflammatory phase of wound healing had a significant effect on later events in the wound healing process, namely a reduction in scar tissue formation, without disrupting reepithelialization or decreasing tensile strength. Our data suggest that in the absence of infection, adult wound healing is able to commence with decreased inflammation and that anti-inflammatory drugs may be used to improve the outcome of the repair process in the skin by limiting scar formation. 相似文献
45.
Functional or unexplained medical symptoms (physical symptoms that are not adequately explained by organic factors and where a major role for psychological factors is assumed) are common amongst children in the general population but can also be an expression of somatisation and somatoform disorders. Co-morbid psychopathology is common. We describe measures mostly used in research into problems related to somatisation in children and adolescents that may be helpful to clinical researchers. Some address the nature and severity of physical symptoms, others document illness attitudes, beliefs and functional impairment, and a third group assesses emotional symptoms. Questionnaires can be helpful for clinicians in quantifying (i) the nature and severity of somatic symptoms and associated functional impairment, (ii) contributory health attitudes and illness beliefs and (iii) co-morbid or primary anxiety and depressive disorders. Together with pain and activity diaries and careful documentation of school attendance, these measures may also be helpful in monitoring treatment response. 相似文献
46.
Effect of olanzapine treatment on platelet glutamine synthetase-like protein and glutamate dehydrogenase immunoreactivity in schizophrenia. 总被引:1,自引:0,他引:1
Gulnur Sh Burbaeva Irina S Boksha Elena B Tereshkina Olga K Savushkina Marina S Turishcheva Lubov I Starodubtseva Oleg S Brusov Margarita A Morozova 《The world journal of biological psychiatry》2006,7(2):75-81
According to contemporary views, the glutamatergic system is implicated in the pathogenesis of schizophrenia, and atypical neuroleptics exert their effects (at least partially) through the glutamatergic system. Immunoreactive glutamate-metabolising enzymes, such as glutamine synthetase-like protein (GSLP) and two glutamate dehydrogenase isoenzymes (GDH), have been discovered in human platelets. The amount of GSLP in the platelets of 40 chronic patients with schizophrenia was found to be significantly higher than in 33 controls (consistent with our previous finding of increased amounts of GSLP in the prefrontal cortex of chronic schizophrenia patients). Moreover, survival analysis of the group of patients treated with olanzapine for 28 weeks showed that the larger amount of GSLP measured in platelets before treatment, the shorter the treatment time needed to achieve a positive clinical response (defined a priori as > or = 20% reduction in PANSS total score from the initial level before the treatment). Hence, GSLP level may serve as a predictor of the treatment duration to achieve a positive outcome with olanzapine. Both GSLP and GDH were found significantly changed in the course of treatment; hence, treatment with olanzapine influences the amounts of glutamate-metabolising enzymes in the platelets of chronic schizophrenia patients. 相似文献
47.
Full-thickness tears of the rotator cuff of the shoulder: diagnosis with MR imaging. 总被引:4,自引:0,他引:4
T E Farley C H Neumann L S Steinbach A J Jahnke S S Petersen 《AJR. American journal of roentgenology》1992,158(2):347-351
The purpose of this study was to describe MR findings in full-thickness tears of the rotator cuff. Of 102 shoulders examined by MR imaging, 31 were found to have a full-thickness tendon tear at arthroscopy/bursoscopy (five shoulders) or open surgery (26 shoulders). All shoulders were imaged in oblique coronal and axial planes. MR images of the 102 shoulders were evaluated for (1) the presence of fluid in the subacromial and subdeltoid bursae; (2) abnormal signal of the supraspinatus, subscapularis, infraspinatus, and teres minor tendons; (3) interruption of tendon continuity and thinning of the tendon; and (4) proximal retraction of the junction of the muscle and tendon. The presence or absence of each finding was determined by consensus of two radiologists, who interpreted the images without knowledge of the surgical findings. Results in those 31 shoulders with proved full-thickness tears were: fluid in the subacromial bursae (29 shoulders), interruption of tendinous continuity (22 shoulders), focally increased signal of the tendon equivalent to that of water (27 shoulders), and musculotendinous retraction (24 shoulders). The finding of subacromial fluid was a sensitive indicator (93%) of a full-thickness tear, and interruption of tendinous continuity was a specific finding (96%) in diagnosing a full-thickness tear. Our experience shows interruption of tendon continuity is the most specific MR finding of full-thickness rotator cuff tears, while subacromial fluid is the most common finding. 相似文献
48.
Francisco J. Romero Juan Segura-Aguilar Elena Monsalve Carlos Hermenegildo Eberhard Nies Francisco J. Puertas Joaquí n Rom 《Neurotoxicology and teratology》1990,12(6):603-605
The present work tries to establish the antioxidant capacity of the peripheral nervous tissue of the rat, in terms of the enzymatic activities present in this tissue that either prevent the formation of activated species as the semiquinone radical (DT-diaphorase), protect against activated oxygen species (superoxide dismutase, glutathione peroxidase), conjugate natural toxic products or xenobiotics (glutathione S-transferases, especially the activity conjugating 4-hydroxy-nonenal), or complete the glutathione system metabolism (glutathione disulfide reductase, γ-glutamyl transpeptidase). All the activities studied are lower in this tissue than they are in liver, except for γ-glutamyl transpeptidase. The relevance of the results obtained and its possible relationship with different neuropathies is discussed. It is concluded that the peripheral nervous tissue is by far less protected than the liver against oxidative damage. 相似文献
49.
Central administration of ACTH in rats induces yawning and stretching. In order to study the effects of REM sleep deprivation on ACTH-induced yawning, the peptide was injected immediately after the REM sleep deprivation period or 24 h later. REM sleep deprivation impaired ACTH-induced yawning, but after a 24-hour recovery period, rats displayed a number of yawns similar to those in control animals. Implications for an involvement of dopaminergic and mainly cholinergic systems are discussed. 相似文献
50.
Iwar Klime Antonian Vraana Jaroslav Kune Elena eboUkovaA Zdena Dobe ovaa Pavel tolba Josef Zicha 《Blood pressure》1995,4(3):137-142
Hereditary hypertriglyceridemic rats (hHTg) were developed as a new genetic model for the study of relationships between blood pressure (BP) and metabolic abnormalities. This strain has been produced by selective inbreeding from Wistar rats according to the rise of plasma triglycerides induced by a high-sucrose diet. Though hHTg rats display hypertriglyceridemia, impaired glucose tolerrance, hyperinsulinemia, insulin resistance and increased BP even without nutritional stimuli, high sucrose feeding further aggravates these symptoms. High plasma triglycerides levels in hHTg rats seem to be a consequence of their hyperproduction. Impaired insulin action is responsible for the defective glucoregulation in this strain. The loss of insulin responsiveness might be due to a reduction in the number of glucose transporters. Highly significant relationships among plasma triglycerides, ouabain-resistant Na+ transport and BP were demonstrated in the hHTg rats. Segregating populations (F2 hybrids) should be used for genetic analysis of the primary role of lipid and/or ion transport abnormalities in the pathogenesis of this form of genetic hypertension. 相似文献