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81.
In a previous report we demonstrated Epstein-Barr virus expression in cutaneous squamous cell carcinomas from heart transplant recipients. In a comparative study, skin lesions from renal allograft recipients were investigated for the presence of Epstein-Barr virus. Thirty cutaneous squamoproliferative lesions from 10 kidney transplant recipients were examined for Epstein-Barr virus-specific gene expression. The techniques used for detection were polymerase chain reaction, in situ hybridization and immunohistochemistry. Epstein-Barr virus DNA was not detected by polymerase chain reaction in the neoplasias, and only single Epstein-Barr virus-positive carcinoma cells were shown by in situ hybridization in three cases of infiltrative squamous cell carcinomas. Immunohistochemistry for Epstein-Barr virus latent membrane protein 1 showed a negative result in all samples. These findings differ from our earlier investigations of cutaneous squamous cell carcinomas from heart transplant recipients where Epstein-Barr virus expressions were common. This may indicate that the part Epstein-Barr virus plays in the development of post-transplant, cutaneous squamoproliferative disorders is related to type of organ transplantation and/or grade of immunosuppression. 相似文献
82.
Rats deprived of vitamin E from age of 4 weeks were tested in four independent behavioral experiments and compared with a group fed a control diet. During a 14-minute session in a hole-board, no differences in the level and the course of habituation of parameters of activity and exploration were found. A second group of animals was trained in an automatically controlled six-arm radial tunnel maze. Although no differences were found in various activity measurements, the deprived animals showed a slightly impaired spatial concept formation during 8 acquisition sessions. Testing their relearning ability of the same maze 18 days later, the vitamin E deprived animals showed a significant impairment. In a third experiment, animals were trained 16 days in the same maze configuration and at day 17 they were exposed to the mirror image of the radial maze. Both groups mastered this reversal with an increased level of activity but without differences in patrolling efficiency. In a fourth behavioral experiment, the effects of scopolamine on deprived animals were examined. Compared to the controls, the vitamin E deprived animals were relatively insensitive to the effects of scopolamine. Autofluorescent neuronal lipofuscin accumulation was found especially in the hippocampus (CA3) of vitamin E deprived animals. Based on these results, the usefulness of vitamin E deprivation as an animal model for accelerated normal aging is discussed. 相似文献
83.
Heilig M Zachrisson O Thorsell A Ehnvall A Mottagui-Tabar S Sjögren M Asberg M Ekman R Wahlestedt C Agren H 《Journal of psychiatric research》2004,38(2):113-121
Extensive animal studies suggest neuropeptide Y (NPY) to be involved in coping with a wide range of stressors, and that impaired central NPY signalling could be involved in the pathophysiology of anxiety and depression. Human studies of central NPY levels in depression have, however, been inconclusive. Here, we examined levels of NPY-like immunoreactivity (NPY-LI) in the cerebrospinal fluid (CSF) of medication-free subjects with treatment refractory unipolar depression. Patients were admitted to a research inpatient unit, examined under standardized conditions, and compared with a sample of volunteers in whom psychiatric morbidity was excluded. A robust suppression of NPY levels in patient CSF was found, while other putative CSF markers (monoamine metabolites, somatostatin) did not differ between the groups. We then explored whether this finding might be related to a recently described T1128C coding polymorphism which results in a Leu7-> Pro7 substitution of the signal peptide, and a previously not described T -399C polymorphism in the promoter region of the preproNPY gene. Preliminary evidence was found for an association of both markers with a diagnosis of depression, indicating the possibility of an underlying haplotype influencing the vulnerability for developing depressive illness. Our present findings are in line with an extensive animal literature, and further support the notion that impaired NPY function could contribute to depressive illness. 相似文献
84.
OBJECTIVES: We used two different strains of Escherichia coli, E.coli ATCC 25922 and a recent urinary isolate from a clinical sample, to investigate in vitro how the MIC and mutant prevention concentration (MPC) are affected by different temperatures (37 or 20 degrees C) or oxygen tension (aerobic or anaerobic atmosphere; MIC, MIC(an); MPC, MPC(an)).Materials and methods: MIC and MPC for E.coli ATCC 25922 and the clinical isolate were determined on agar containing ciprofloxacin or levofloxacin, and for the ATCC strain on agar supplemented with nalidixic acid, norfloxacin, ofloxacin, sparfloxacin, trovafloxacin or clinafloxacin. RESULTS: Results for the ATCC strain and the clinical strain for ciprofloxacin or levofloxacin were similar. The MPC values for E.coli ATCC 25922 were 2 x MIC (trovafloxacin), 4 x MIC (ciprofloxacin, norfloxacin, ofloxacin), 8 x MIC (clinafloxacin, levofloxacin), 16 x MIC (sparfloxacin) and 32 x MIC (nalidixic acid) at 37 degrees C and under aerobic conditions. Generally, a 37 degrees C aerobic atmosphere was associated with the highest MPC values. As an exception, both the MIC and the MPC of ciprofloxacin were higher under anaerobic versus aerobic conditions (MIC(an) approximately 8 x MIC; MPC(an) = 4 x MPC) for both E.coli isolates. Irrespective of the quinolone or growth conditions, the MIC for mutants was 1-256 x wild-type MIC. Calculated from published serum half-lives and the MPC values from this study, a putative selection period, in which resistant mutants might be selected, was calculated to be 14 h for nalidixic acid, 16 h for norfloxacin and ciprofloxacin, 28 h for ofloxacin, 30 h for trovafloxacin, 35 h for levofloxacin, 40 h for clinafloxacin, and 120 h for sparfloxacin. CONCLUSIONS: As calculated from our model in respect to the length of the selection period, long serum half-lives of recently developed compounds could not be compensated for by a more favourable activity in terms of MPC. Higher concentrations of ciprofloxacin may be required under an anaerobic atmosphere to prevent the emergence of resistant mutants among 10(10) cfu. 相似文献
85.
In vivo increase in resistance to ciprofloxacin in Escherichia coli associated with deletion of the C-terminal part of MarR 总被引:3,自引:0,他引:3 下载免费PDF全文
Linde HJ Notka F Metz M Kochanowski B Heisig P Lehn N 《Antimicrobial agents and chemotherapy》2000,44(7):1865-1868
We recovered two isolates (EP1 and EP2) of Escherichia coli from the same patient that had identical pulsed-field gel electrophoresis patterns but required different MICs of ciprofloxacin (CIP): 16 and 256 mg/liter for EP1 and EP2, respectively. Both isolates had mutations in the quinolone resistance-determining regions of GyrA (Ser83Leu and Asp87Tyr) and ParC (Ser80Ile), but not in those regions of GyrB or ParE. Isolate EP2 was also more resistant to chloramphenicol, tetracyclines, cefuroxime, and organic solvents. A deletion of adenine (A) 1821 was found in marR of isolate EP2, which resulted in an 18-amino-acid C-terminal deletion in the MarR protein. The causative relationship between DeltaA1821 and the Mar phenotype was demonstrated both by the replacement of the wild-type marR by marR DeltaA1821 in isolate EP1 and by complementation with the wild-type marR in trans in isolate EP2. In isolate EP2 complemented with wild-type marR, susceptibility to chloramphenicol was restored completely, whereas susceptibility to CIP was restored only incompletely. Northern blotting demonstrated increased expression of marA and acrAB but not of soxS in isolate EP2 compared to EP1. In conclusion, the deletion of A1821 in marR in the clinical isolate EP2 caused an increase in the MICs of CIP and unrelated antibiotics. Presumably, the C-terminal part of MarR is necessary for proper repressor function. 相似文献
86.
Nils Milman Claus B. Andersen Bo Baslund Annika Loft Martin Iversen 《The clinical respiratory journal》2007,1(2):106-113
Background: Sarcoid granuloma formation involves the orchestration of cytokines and chemokines, which modulate the host's immune response to the antigen stimulus. The release of cytokines enhances expression of the pro‐inflammatory cytokine tumour necrosis factor‐α (TNF), which plays a crucial role in the formation of sarcoid granuloma, being released from T‐lymphocytes and alveolar macrophages. Objective: The aim of this study was to evaluate the effect of infliximab in a case of pulmonary sarcoidosis using a histological approach. Materials and Methods: A 44‐year‐old man with biopsy verified chronic pulmonary sarcoidosis being resistant to treatment with corticosteroids and cell cycle inhibitors. Persisting disease activity was confirmed by declining lung function tests and a positive fluorine‐18‐fluorodeoxyglucose–positron emission tomography scan. The patient was treated with a single course of infliximab 3‐mg/kg body weight; 11 days later, a single lung transplantation was performed. Immunohistological staining with the macrophage marker CD68 was performed on lung tissue and mediastinal lymph node tissue from both the initial diagnostic evaluation (prior to infliximab) as well as from the explanted lung (after infliximab). Results: Biopsy specimens from lung and mediastinal lymph nodes prior to infliximab demonstrated sarcoid granulomas, and staining with CD68 showed dense infiltration by macrophages (epithelioid cells) in the central part of the granulomas. In contrast, biopsies from the explanted lung after infliximab demonstrated acellular sarcoid granulomas with central amorphous masses, and staining with CD68 showed complete absence of macrophages. Conclusions: In this patient, the TNF inhibitor infliximab appeared to induce resolution of sarcoid granulomas starting with disappearance of macrophages probably caused by cell lysis or apoptosis. Please cite this paper as: Milman N, Andersen CB, Baslund B, Loft A and Iversen M. Does tumour necrosis factor‐α inhibitor infliximab induce histological resolution of pulmonary sarcoid granulomas? The Clinical Respiratory Journal 2007; 1:106–113. 相似文献
87.
88.
Quantitative detection of respiratory Chlamydia pneumoniae infection by real-time PCR 总被引:3,自引:0,他引:3 下载免费PDF全文
Kuoppa Y Boman J Scott L Kumlin U Eriksson I Allard A 《Journal of clinical microbiology》2002,40(6):2273-2274
Real-time PCR was evaluated as a quantitative diagnostic method for Chlamydia pneumoniae infection using different respiratory samples. Real-time PCR had efficiency equal to or better than that of nested touchdown PCR. This study confirmed sputum as the best sampling material to detect an ongoing C. pneumoniae infection. 相似文献
89.
Objective
To investigate women's expectations of routine ultrasound and experiences when soft markers were discovered: what the disclosure meant, how it affected them, how they experienced the information given and why they did or did not choose amniocentesis.Design
Semi-structured, in-depth interviews were conducted with 11 women 25-30 weeks into the pregnancy, 7-13 weeks after the discovery of a soft marker.Findings
Women lacked knowledge about the potential of the scan and detection of soft markers created strong emotional reactions that women thought could have been alleviated by prior information about potential findings. Information in connection with the scan was perceived as insufficient. Decision about amniocentesis was affected by attitudes to disability, anxiety about fetal loss due to the procedure, need for certainty by a diagnostic test, and partner's opinion.Conclusions
Women were shocked by the unexpected and sometimes unwanted information on elevated risk for a chromosomal aberration for which they lacked any preparation. Because this event often has long-lasting effects on the pregnancy, models of information that are efficient in promoting informed decisions are imperative.Practice implications
Both women and their partners need relevant information before and in connection with ultrasound scan to be able to make informed choices. 相似文献90.
Chunyan Liu Lena Grillner Klas Jonsson Annika Linde Kunling Shen Annika Tiveljung Lindell Benita Zweygberg Wirgart Kari Johansen 《Journal of clinical virology》2006,35(1):69-72
BACKGROUND: Viral diarrhea remains a major cause of childhood morbidity and mortality worldwide. Although rotavirus was extensively studied in China, few comprehensive studies of all viral agents related to diarrhea in children have been conducted. OBJECTIVES: Our study was performed to investigate the role of enteric viruses in acute diarrhea in our country and to evaluate methods that could be used in routine diagnostics. STUDY DESIGN: One hundred stool samples were collected from children under 5 years of age seeking medical care for acute diarrhea during the winter season 2000/2001 in Beijing Children's Hospital. All specimens were initially screened microscopically for leucocytes/red blood cells. Samples with negative results were analyzed for virus presence using commercial EIAs and/or in-house RT-PCRs. RESULTS: At least one viral agent was found in 67% of the specimens. The frequency of rotavirus, astrovirus, norovirus and enteric adenovirus was 59%, 8%, 6% and 2%, respectively. Dual infections were found in 9.0% (6/67) of the positive samples. The results from rotavirus and astrovirus EIAs were concordant with those of rotavirus and astrovirus RT-PCRs. CONCLUSIONS: Enteric viruses play an important role in pediatric diarrhea during the winter season in China. A combination of microscopic examination of stool samples with specific EIA assays to detect virus antigen in stool specimens may be suitable for routine diagnostics. 相似文献