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41.
Quantitative Analysis of Mycobacterial and Propionibacterial DNA in Lymph Nodes of Japanese and European Patients with Sarcoidosis 总被引:10,自引:0,他引:10 下载免费PDF全文
Yoshinobu Eishi Moritaka Suga Ikuo Ishige Daisuke Kobayashi Tetsuo Yamada Tamiko Takemura Touichiro Takizawa Morio Koike Shoji Kudoh Ulrich Costabel Josune Guzman Gianfranco Rizzato Marcello Gambacorta Ronald du Bois Andrew G. Nicholson Om P. Sharma Masayuki Ando 《Journal of clinical microbiology》2002,40(1):198-204
The cause(s) of sarcoidosis is unknown. Mycobacterium spp. are suspected in Europe and Propionibacterium spp. are suspected in Japan. The present international collaboration evaluated the possible etiological links between sarcoidosis and the suspected bacterial species. Formalin-fixed and paraffin-embedded sections of biopsy samples of lymph nodes, one from each of 108 patients with sarcoidosis and 65 patients with tuberculosis, together with 86 control samples, were collected from two institutes in Japan and three institutes in Italy, Germany, and England. Genomes of Propionibacterium acnes, Propionibacterium granulosum, Mycobacterium tuberculosis, Mycobacterium avium subsp. paratuberculosis, and Escherichia coli (as the control) were counted by quantitative real-time PCR. Either P. acnes or P. granulosum was found in all but two of the sarcoid samples. M. avium subsp. paratuberculosis was found in no sarcoid sample. M. tuberculosis was found in 0 to 9% of the sarcoid samples but in 65 to 100% of the tuberculosis samples. In sarcoid lymph nodes, the total numbers of genomes of P. acnes or P. granulosum were far more than those of M. tuberculosis. P. acnes or P. granulosum was found in 0 to 60% of the tuberculosis and control samples, but the total numbers of genomes of P. acnes or P. granulosum in such samples were less than those in sarcoid samples. Propionibacterium spp. are more likely than Mycobacteria spp. to be involved in the etiology of sarcoidosis, not only in Japanese but also in European patients with sarcoidosis. 相似文献
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43.
Assessment of fetal-maternal haemorrhage in mothers with hereditary persistence of fetal haemoglobin. 下载免费PDF全文
W N Patton G S Nicholson A H Sawers I M Franklin F A Ala A W Simpson 《Journal of clinical pathology》1990,43(9):728-731
Kleihauer examination of peripheral blood cannot be used reliably to detect transplacental fetal-maternal haemorrhage in mothers with hereditary persistence of fetal haemoglobin (HPFH). In Rh(D) negative pregnancies diagnostic confusion with a large fetal-maternal haemorrhage could result in the administration of inappropriately excessive amounts of anti-D immunoglobulin, and the inability to diagnose and quantify transplacental haemorrhage in maternal HPFH by current methods could result in insufficient anti-D administration and subsequent Rh(D) sensitisation. Accordingly, a method to detect and quantify fetal-Rh(D) positive maternal haemorrhage using erythrocyte fluorescent immunocytometry was developed. An indirect immunofluorescence method with IgG anti-D immunoglobulin as the primary antibody was used, combined with quantitative analysis on a fluorescence activated cell sorter. The method was accurate, specific, and sensitive and could detect a contaminating population of 0.1% Rh(D) positive cells in Rh(D) negative blood--a level of fetal-maternal haemorrhage well covered by a single dose of 500 IU of anti-D immunoglobulin. 相似文献
44.
Perry JD Butterworth LA Nicholson A Appleby MR Orr KE 《Journal of clinical pathology》2003,56(7):528-531
AIMS: To compare the performance of a new chromogenic medium, Uriselect 4, with cystine lactose electrolyte deficient (CLED) agar and an established chromogenic agar, CPS ID 2 medium, for detection of urinary tract pathogens. METHODS: Using a semiquantitative culture method, 777 samples were inoculated on to the three test media in duplicate. All bacterial strains that yielded a potentially significant growth were observed for colony colour and identified using standard methods. RESULTS: Of the 777 samples tested, 589 urine samples yielded potentially significant growth of at least one strain. A total of 811 strains were isolated on at least one of the three media. A total of 168 urine samples yielded a mixture of at least two strains. Uriselect 4 medium showed the best sensitivity of the three media and only failed to recover 14 strains (1.7%). CPS ID 2 medium failed to recover 22 strains (2.7%). CLED medium showed the worst recovery and failed to recover 74 strains (9.1%). Both chromogenic media allowed for identification of Escherichia coli with a high degree of specificity (98% for Uriselect 4, 99.7% for CPS ID 2). Inclusion of a spot indole test increased the specificity of both chromogenic media to 100% for E coli. CONCLUSIONS: Uriselect 4 and CPS ID 2 were superior to CLED medium for the isolation of urinary tract pathogens mainly because of their ability to discriminate mixed cultures. Both chromogenic media were also useful for the preliminary identification of the most common urinary tract pathogens. 相似文献
45.
Immunoblot analysis of immunoglobulin G response to the Lyme disease agent (Borrelia burgdorferi) in experimentally and naturally exposed dogs. 总被引:10,自引:8,他引:10 下载免费PDF全文
R T Greene R L Walker W L Nicholson H W Heidner J F Levine E C Burgess M Wyand E B Breitschwerdt H A Berkhoff 《Journal of clinical microbiology》1988,26(4):648-653
Immunoblots were used to study the immunoglobulin G response to Borrelia burgdorferi in experimentally and naturally exposed dogs. Adsorption studies confirmed that the antibodies were specific for B. burgdorferi. Experimentally exposed dogs were asymptomatic. Naturally exposed dogs included both asymptomatic animals and animals showing signs compatible with Lyme disease. Naturally exposed dogs were from four geographic regions of the country. No differences were detected between immunoblot patterns of naturally exposed symptomatic or asymptomatic dogs from different areas of the country. The immunoblot patterns obtained with sera from experimentally exposed dogs were different from those obtained with sera from naturally exposed dogs and were characterized by reactivity to fewer and different protein bands. Immunoblot analysis using an OspA-protein-producing Escherichia coli recombinant showed that experimentally exposed dogs produced antibodies to OspA, whereas naturally exposed dogs did not. Modifications of the immune response over time, different routes of antigen presentation, and strain variation are factors postulated to account for the observed differences. 相似文献
46.
Use of a group-reactive and other monoclonal antibodies in an enzyme immunodot assay for identification and presumptive serotyping of aquatic birnaviruses. 下载免费PDF全文
P Caswell-Reno V Lipipun P W Reno B L Nicholson 《Journal of clinical microbiology》1989,27(9):1924-1929
A panel of monoclonal antibodies (MAbs) was prepared and used to develop an enzyme immunodot assay for the rapid identification and presumptive serotyping of aquatic birnaviruses. Comparison of the reaction patterns of these MAbs with representative virus isolates indicated that one MAb recognizes a serogroup-reactive epitope and can therefore be used for identification of all serogroup A aquatic birnaviruses, the predominant serotype worldwide. Other MAbs exhibited more restrictive specificities, permitting the presumptive serotyping of viruses of the three recognized serotypes and the identification of some individual strains. This assay, in which MAbs are used, is more efficient in terms of time, cost, and case of performance and provides significant advantages in specificity and standardization compared with currently used tests. 相似文献
47.
Ayala-Grosso C Tam J Xanthoudakis S Bureau Y Roy S Nicholson DW Robertson GS 《Neuroscience》2004,126(4):927-940
The ability of fimbria-fornix bilateral axotomy to elicit calpain and caspase-3 activation in the rat septohippocampal pathway was determined using antibodies that selectively recognize either calpain- or caspase-cleaved products of the cytoskeletal protein alphaII-spectrin. Radioenzymatically determined choline acetyl transferase (ChAT) activity was elevated in the septum at day 5, but reduced in the dorsal hippocampus at days 3, 5 and 7, after axotomy. Prominent accumulation of calpain-, but not caspase-3-, cleaved spectrin proteolytic fragments was observed in both the septum and dorsal hippocampus 1-7 days after axotomy. ChAT-positive neuronal cell bodies in the septum also displayed calpain-cleaved spectrin indicating that calpain activation occurred in cholinergic septal neurons as a consequence of transection of the septohippocampal pathway. Calpain-cleaved alphaII-spectrin immunoreactivity was observed in cholinergic fibers coursing through the fimbria-fornix, but not in pyramidal neurons of the dorsal hippocampus, suggesting that degenerating cholinergic nerve terminals were the source of calpain activity in the dorsal hippocampus following axotomy. Accumulation of calpain-cleaved spectrin proteolytic fragments in the dorsal hippocampus and septum at day 5 after axotomy was reduced by i.c.v. administration of two calpain inhibitors. Calpain inhibition partially reduced the elevation of ChAT activity in the septum produced by transection but failed to decrease the loss of ChAT activity in the dorsal hippocampus following axotomy. These findings suggest that calpain activation contributes to the cholinergic cell body response and hippocampal axonal cytoskeletal degradation produced by transection of the septohippocampal pathway. 相似文献
48.
Wei F Cheng S Badie N Elder F Scott C Nicholson L Ross JL Zinn AR 《American journal of medical genetics》2001,102(4):353-358
We report on a man with neurofibromatosis type 1 (NF1) and Leri-Weill dyschondrosteosis (LWD). His father had NF1. His mother had LWD plus additional findings of Turner syndrome (TS): high arched palate, bicuspid aortic valve, aortic stenosis, and premature ovarian failure. The proband's karyotype was 46,X,dic(X;Y)(p22.3;p11.32). Despite having almost the same genetic constitution as 47,XXY Klinefelter syndrome, he was normally virilized, although slight elevation of serum gonadotropins indicated gonadal dysfunction. His mother's karyotype was mosaic 45,X[17 cells]/46,X,dic(X;Y)(p22.3;p11.32)[3 cells].ish dic(X;Y)(DXZ1 +,DYZ1 + ). The dic(X;Y) chromosome was also positive for Y markers PABY, SRY, and DYZ5, but negative for SHOX. The dic(X;Y) chromosome was also positive for X markers DXZ1 and a sequence < 300 kb from PABX, suggesting that the deletion encompassed only pseudoautosomal sequences. Replication studies indicated that the normal X and the dic(X;Y) were randomly inactivated in the proband's lymphocytes. LWD in the proband and his mother was explained by SHOX haploinsufficiency. The mother's female phenotype was most likely due to 45,X mosaicism. This family segregating Mendelian and chromosomal disorders illustrates extreme sex chromosome variation compatible with normal male and female sexual differentiation. The case also highlights the importance of karyotyping for differentiating LWD and TS, especially in patients with findings such as premature ovarian failure or aortic abnormalities not associated with isolated SHOX haploinsufficiency. 相似文献
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50.
An immunogenetic analysis of the T-cell recognition of the major house dust mite allergen Der p 2: identification of high- and low-responder HLA-DQ alleles and localization of T-cell epitopes. 下载免费PDF全文
Cellular reactivity to Der p 2, a major allergen of the house dust mite (HDM) Dermatophagoides pteronyssinus, was studied in a group of 41 symptomatic HDM sensitive patients, using fresh peripheral blood mononuclear cells (PBMC) and assays of proliferation. Sixty per cent of the patients responded to Der p2, with reactivities being greater in patients with asthma as one of their clinical manifestations and also in those who had skin-test reactivity to a number of allergens. HLA-DR and -DQ serotyping was undertaken in 39 of the patients and the magnitude of T-cell proliferative responses to Der p 2 were found to be positively associated with DQ7 and negatively associated with DQ2. T-cell determinants within the Der p 2 molecule were identified by assays using a series of overlapping peptides (15- to 19-mers) spanning the entire protein. Fifty-nine per cent of the 41 HDM-sensitive patients responded to one or more of the peptides. All of the peptides were antigenic for at least one of the individuals, indicating the heterogeneity of the human repertoire reactive with Der p 2. There was a substantial variability in the number and location of epitopes recognized by T cells from the different allergic patients, the mean number per patient being 2.3 +/- 1.3 (SD). The most frequently recognized peptide was that spanning residues 111-129, being stimulatory in 66.7%, the other peptides were each recognized by between 8 to 25% of individuals. There was no correlation between the epitope recognized and the presence of particular HLA-DQ antigens. 相似文献