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排序方式: 共有1021条查询结果,搜索用时 15 毫秒
1.
P B Schneider U Denk M Breitenbach K Richter P Schmid-Grendelmeier S Nobbe M Himly A Mari C Ebner B Simon-Nobbe 《Clinical and experimental allergy》2006,36(12):1513-1524
BACKGROUND: Alternaria alternata is one of the most important allergenic fungi worldwide. Mannitol dehydrogenase (MtDH) has previously been shown to be a major allergen of Cladosporium herbarum and cross-reactivity has been demonstrated for several fungal allergens. OBJECTIVE: The present study's objective was to clone the MtDH from an A. alternata cDNA library, express and purify the recombinant non-fusion protein and test its IgE-binding properties. Methods A cDNA library prepared from A. alternata hyphae and spores was screened for mannitol dehydrogenase by DNA hybridization with the radioactively labelled C. herbarum homologue as a probe. The resulting clone was sequenced and heterologously expressed in Escherichia coli as a recombinant non-fusion protein, which was purified to homogeneity and analysed for its IgE-binding capacity. RESULTS: The coding sequence of the full-length cDNA clone comprises 798 bp encoding a protein with a molecular mass of 28.6 kDa and a predicted pI of 5.88. Protein sequence analysis revealed an identity of 75% and a homology of 86% between the MtDHs of A. alternata and C. herbarum. The functional mannitol dehydrogenase was expressed in the E. coli strain BL21(DE3) transformed with the vector pMW172 and purified to homogeneity. The enzyme catalyses the NADPH-dependent conversion of d-fructose to d-mannitol. In IgE-ELISA and immunoblots, MtDH is recognized by 41% of A. alternata-allergic patients. In vivo immunoreactivity of the recombinant MtDH was verified by skin prick testing. Finally, inhibition-ELISA experiments confirmed cross-reactivity between the MtDHs of A. alternata and C. herbarum. CONCLUSION: Mannitol dehydrogenase (Alt a 8) represents an important new allergen of the ascomycete A. alternata that might be suitable for improving diagnostic and therapeutic procedures. 相似文献
2.
BACKGROUND: There are obvious advantages to increasing donor retention. However, for reasons of blood safety, certain donors may, in fact, be more desirable to retain than others. “Safe” donors are defined as those who provided a blood donation that was negative on all laboratory screening tests and who subsequently reported no behavioral risks in response to an anonymous survey. This study identifies the most important factors affecting the intention of “safe” donors to provide another donation. STUDY DESIGN AND METHODS: An anonymous survey asking about donation history, sexual history, injecting drug use, and recent donation experience was mailed to 50,162 randomly selected allogeneic donors (including directed donors) who gave blood from April through July or from October through December 1993 at one of the five United States blood centers participating in the Retrovirus Epidemiology Donor Study. Before mailing, questionnaires were coded to designate donors with nonreactive laboratory screening tests at their most recent donation. RESULTS: A total of 34,726 donors (69%) responded, with substantially higher response among repeat donors. According to reported intentions only, the vast majority of “safe” donors indicated a high likelihood of donating again within the next 12 months. Only 3.4 percent reported a low likelihood of donating again. A comparison of those likely to return and those unlikely to return reveals significant differences in demographics and in ratings of the donation experience. A higher proportion of those unlikely to return were first-time donors, minority-group donors, and donors with less education. The highest projected loss among “safe” donors was seen for those who gave a fair to poor assessment of their treatment by blood center staff or of their physical well-being during or after donating. CONCLUSION: These data suggest that efforts to improve donors' perceptions of their donation experience, as well as attention to the physical effects of blood donation, may aid in the retention of both repeat and first-time donors. 相似文献
3.
Zusammenfassung. Bei einem 39 j?hrigen ?sterreichischen Staatsbürger chinesischer Herkunft wurden nach einer Latenzzeit von etwa 20 Jahren
nicht nur in dem chirurgisch entfernten Rectumcarcinom, sondern auch in der das Carcinom umgebenden chronisch entzündlich
ver?nderten Rectumschleimhaut mit verschiedenen Schweregraden der Dysplasie und in einem tumor?s befallenen benachbarten Lymphknoten,
Wurmeier nachgewiesen und daher ein kausaler Zusammenhang angenommen. W?hrend aber der ?tiologische Zusammenhang einer chronischen
Infektion mit Schistosoma haematobium und dem geh?uften endemischen Auftreten von Blasenkrebs als gesichert gilt, wird bei
den intestinalen Formen der chronischen Schistosomiasis eine erh?hte Carcinomkoinzidenz kontrovers beurteilt. ?tiologisch
und pathogenetisch ist die Kausalit?t zwischen Wurmeiablage und sp?terem Carcinom ?hnlich zu sehen wie bei anderen entzündlichen
Dickdarmerkrankungen, wo es über die Sequenz chronische Entzündung/schwere Dysplasie zur sp?teren Carcinomentstehung kommen
kann. Neben einer übersicht über die Parasitologie und Pathologie dieser Trematodenerkrankung wird der ?tiologische und pathogenetische
Zusammenhang zwischen Rectumcarcinom und Schistosomiasis japonicum anhand entsprechender Literaturstellen hergestellt.
相似文献
4.
Steenbergen EJ; Verhagen OJ; van Leeuwen EF; van den Berg H; von dem Borne AE; van der Schoot CE 《Blood》1995,86(2):692-702
Crosslineage T-cell receptor delta (TCR delta) rearrangements are widely used as tumor markers for the follow up of minimal residual disease in childhood B-precursor acute lymphoblastic leukemia (ALL) by polymerase chain reaction (PCR). The major drawback of this approach is the risk of false-negative results due to clonal evolution. We investigated the stability of V delta 2D delta 3 rearrangements in a group of 56 childhood B-precursor ALL patients by PCR and Southern blot analysis. At the PCR level, V delta 2D delta 3-to-J alpha rearranged subclones (one pathway for secondary TCR delta recombination) were demonstrated in 85.2% of V delta 2D delta 3-positive patients tested, which showed that small subclones are present in the large majority of patients despite apparently monoclonal TCR delta Southern blot patterns. Sequence analysis of V delta 2D delta 3J alpha rearrangements showed a biased J alpha gene usage, with HAPO5 and J alpha F in 26 of 32 and 6 of 32 clones, respectively. Comparison of V delta 2D delta 3 rearrangement status between diagnosis and first relapse showed differences in seven of eight patients studied. In contrast, from first relapse onward, no clonal changes were observed in six patients studied. To investigate the occurrence of crosslineage TCR delta rearrangements in normal B and T cells, fluorescence-activated cell sorter-sorted peripheral blood CD19+/CD3- and CD19-/CD3+ cell populations from three healthy donors were analyzed. V delta 2D delta 3 rearrangements were detected at low frequencies in both B and T cells, which suggests that V delta 2-to-D delta 3 joining also occurs during normal B-cell differentiation. A model for crosslineage TCR delta rearrangements in B-precursor ALL is deduced that explains the observed clonal changes between diagnosis and relapse and is compatible with multistep leukemogenesis of B-precursor ALL. 相似文献
5.
AE Castellano G Micieli P Bellantonio MG Buzzi S Marcheselli F Pompeo F Rossi G Nappi 《Cephalalgia : an international journal of headache》1998,18(9):622-630
Intracerebral vascular reactivity induced by the nitric oxide (NO) donor isosorbide dinitrate (IDN, 5 mg sublingually) is more major and longer-lasting in migraine patients who develop delayed headache in response to the drug. The headache is purportedly due to neuronally-mediated vascular mechanisms. Indomethacin inhibits prostaglandin synthesis, which is involved in NO generation. Indomethacin also decreases cerebral blood flow by constricting precapillary resistance vessels. In the present study, the hemodynamic effects of indomethacin were evaluated in migraine patients and healthy controls by means of transcranial Doppler monitoring. Indomethacin caused a significant decrease in mean flow velocity in the middle cerebral artery. This was an additional effect to the mean velocity decrease induced by IDN. The interactions between the two drugs suggest that their effects on cerebral hemodynamics (and pain) may be of relevance both in understanding the role of NO in migraine pathogenesis and in evaluating symptomatic treatments for migraine attacks. 相似文献
6.
AE Boothroyd BVS Murthy A Darbyshire AJ Petros 《Acta paediatrica (Oslo, Norway : 1992)》1996,85(12):1422-1425
Objective: Right upper lobe collapse is a common radiographic finding in intubated children. We hypothesized that deep suctioning and uncontrolled negative pressures during endotracheal tube suctioning were significant contributory factors. Methods : The incidence of right upper lobe (RUL) collapse in intubated, ventilated children on a paediatric cardiac intensive care unit was determined over a 3-month period ( n = 102). Graduated suction catheters and suction vacuums of < 165 cm H2 O were then introduced. Another prospective audit was carried out 3 months later ( n = 60). Results : We found that 24% developed RUL collapse and 4 developed an apical pneumothorax. Following the introduction of graduated catheters and controlled vacuums pressures, a significant reduction in the incidence of RUL collapse, to 7%, was observed ( p < 0.05). Conclusions : We conclude that high negative pressure and deep-suctioning causes RUL collapse in children. Any lobar collapse not only prolongs the child's stay in intensive care, but can be associated with further morbidity which may have a serious implication. By improving suctioning technique this morbidity can be significantly reduced. 相似文献
7.
How many lymph nodes are necessary to stage early and advanced adenocarcinoma of the sigmoid colon and upper rectum? 总被引:5,自引:0,他引:5
Leibl S Tsybrovskyy O Denk H 《Virchows Archiv : an international journal of pathology》2003,443(2):133-138
The lymph-node yields in specimens resected for colorectal adenocarcinoma show considerable variations, raising the question whether the minimum lymph-node number recommended by the UICC (International Union Against Cancer) for pN0 classification represents an appropriate quality standard for specimen work-up. The number of pericolic lymph nodes recovered from 568 archival surgical colorectal carcinoma specimens located in the sigmoid or upper rectum showed a highly statistically significant correlation with both the pT category and the presence of metastases (P<0.0005). The median lymph-node yield in standardized (i.e., resembling in size surgically removed cancer specimens) tumor-free specimens obtained during autopsies was 13 lymph nodes, compared with 20.5 when diverticula were present and more than 30 in specimens with chronic inflammation or from patients with systemic infections. In 48 pT2 and pT3 carcinoma specimens prospectively dissected in the same way, median numbers of 18 (pT2) and 23 (pT3) lymph nodes were detected (range between 8 and 39 nodes). The lymph-node numbers recommended in previous studies and by the UICC often seem to be too low to declare a specimen free of metastases. Although the great variation in lymph-node counts requires the recovery of all lymph nodes for pN0 classification, recommendations considering the pT status and additional factors like diverticula and inflammatory changes can be useful as a quality standard for specimen work up. 相似文献
8.
Cytokeratin 8 protects from hepatotoxicity, and its ratio to cytokeratin 18 determines the ability of hepatocytes to form Mallory bodies 总被引:10,自引:0,他引:10
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Zatloukal K Stumptner C Lehner M Denk H Baribault H Eshkind LG Franke WW 《The American journal of pathology》2000,156(4):1263-1274
In alcoholic hepatitis, a severe form of alcohol-induced toxic liver injury, as well as in experimental intoxication of mice with the porphyrinogenic drugs griseofulvin and 3,5-diethoxycarbonyl-1, 4-dihydrocollidine, hepatocytes form cytoplasmic protein aggregates (Mallory bodies; MBs) containing cytokeratins (CKs) and non-CK components. Here we report that mice lacking the CK8 gene and hence CK intermediate filaments in hepatocytes, but still expressing the type I partner, ie, the CK18 gene, do not form MBs but suffer from extensive porphyria and progressive toxic liver damage, leading to the death of a considerable number of animals (7 of 12 during 12 weeks of intoxication). Our observations show that 1) in the absence of CK8 as well as in the situation of a relative excess of CK18 over CK8 no MBs are formed; 2) the loss of CK8 is not compensated by other type II CKs; and 3) porphyria and toxic liver damage are drastically enhanced in the absence of CK8. Our results point to a protective role of CKs in certain types of toxic liver injury and suggest that MBs by themselves are not harmful to hepatocytes but may be considered as a product of a novel defense mechanism in hepatocytes. 相似文献
9.
10.
The GAP-related domain of tuberin, the product of the TSC2 gene, is a target for missense mutations in tuberous sclerosis 总被引:5,自引:0,他引:5
Maheshwar MM; Cheadle JP; Jones AC; Myring J; Fryer AE; Harris PC; Sampson JR 《Human molecular genetics》1997,6(11):1991-1996
Tuberous sclerosis is an autosomal dominant trait in which the
dysregulation of cellular proliferation and differentiation results in the
development of hamartomatous growths in many organs. The TSC2 gene is one
of two genes determining tuberous sclerosis. Inactivating germline
mutations of TSC2 in patients with tuberous sclerosis and somatic loss of
heterozygosity at the TSC2 locus in the associated hamartomas indicate that
TSC2 functions as a tumour suppressor gene and that loss of function is
critical to expression of the tuberous sclerosis phenotype. The TSC2
product, tuberin, has a region of homology with the GTPase activating
protein rap1GAP and stimulates the GTPase activity of rap1a and rab5a in
vitro. Here we show that the region of homology between tuberin and human
rap1GAP and the murine GAP mSpa1 is more extensive than previously reported
and spans approximately 160 amino acid residues encoded within exons 34-38
of the TSC2 gene. Single strand conformation polymorphism analysis of these
exons in 173 unrelated patients with tuberous sclerosis and direct
sequencing of variant conformers together with study of additional family
members enabled characterisation of disease associated mutations in 14
cases. Missense mutations, which occurred in exons 36, 37 and 38 were
identified in eight cases, four of whom shared the same recurrent change
P1675L. Each of the five different missense mutations identified was shown
to occur de novo in at least one sporadic case of tuberous sclerosis. The
high proportion of missense mutations detected in the region of the TSC2
gene encoding the GAP-related domain supports its key role in the
regulation of cellular growth.
相似文献