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71.
Detection and identification of fungi from fungus balls of the maxillary sinus by molecular techniques 下载免费PDF全文
Willinger B Obradovic A Selitsch B Beck-Mannagetta J Buzina W Braun H Apfalter P Hirschl AM Makristathis A Rotter M 《Journal of clinical microbiology》2003,41(2):581-585
The aim of this study was to find a reliable method for the detection and identification of fungi in fungus balls of the maxillary sinus and to evaluate the spectrum of fungi in these samples. One hundred twelve samples were obtained from patients with histologically proven fungal infections; 81 samples were paraffin-embedded tissue sections of the maxillary sinus. In 31 cases, sinus contents without paraffin embedding were sent for investigation. PCR amplification with universal fungal primers for 28S ribosomal DNA and amplicon identification by hybridization with species-specific probes for Aspergillus fumigatus, Aspergillus flavus, Aspergillus niger, Aspergillus terreus, Aspergillus glaucus, Pseudallescheria boydii, Candida albicans, and Candida glabrata were performed for all samples. Furthermore, PCR products were sequenced. Fresh samples were also cultivated. Fungal DNA was detected in all of the fresh samples but only in 71 paraffin-embedded tissue samples (87.7%). Sequence analysis was the most sensitive technique, as results could be obtained for 28 (90.3%) fresh samples by this method in comparison to 24 (77.4%) samples by hybridization and 16 (51.6%) samples by culture. However, sequence analysis delivered a result for only 36 (50.7%) of the paraffin-embedded specimens. Hybridization showed reliable results for A. fumigatus, which proved to be the most common agent in fungus balls of the maxillary sinus. Other Aspergillus species and other genera were rarely found. 相似文献
72.
Deletion of Brca2 exon 27 causes hypersensitivity to DNA crosslinks,chromosomal instability,and reduced life span in mice 总被引:1,自引:0,他引:1
Donoho G Brenneman MA Cui TX Donoviel D Vogel H Goodwin EH Chen DJ Hasty P 《Genes, chromosomes & cancer》2003,36(4):317-331
The Brca2 tumor-suppressor gene contributes to genomic stability, at least in part by a role in homologous recombinational repair. BRCA2 protein is presumed to function in homologous recombination through interactions with RAD51. Both exons 11 and 27 of Brca2 code for domains that interact with RAD51; exon 11 encodes eight BRC motifs, whereas exon 27 encodes a single, distinct interaction domain. Deletion of all RAD51-interacting domains causes embryonic lethality in mice. A less severe phenotype is seen with BRAC2 truncations that preserve some, but not all, of the BRC motifs. These mice can survive beyond weaning, but are runted and infertile, and die very young from cancer. Cells from such mice show hypersensitivity to some genotoxic agents and chromosomal instability. Here, we have analyzed mice and cells with a deletion of only the RAD51-interacting region encoded by exon 27. Mice homozygous for this mutation (called brca2(lex1)) have a shorter life span than that of control littermates, possibly because of early onsets of cancer and sepsis. No other phenotype was observed in these animals; therefore, the brca2(lex1) mutation is less severe than truncations that delete some BRC motifs. However, at the cellular level, the brca2(lex1) mutation causes reduced viability, hypersensitivity to the DNA interstrand crosslinking agent mitomycin C, and gross chromosomal instability, much like more severe truncations. Thus, the extreme carboxy-terminal region encoded by exon 27 is important for BRCA2 function, probably because it is required for a fully functional interaction between BRCA2 and RAD51. 相似文献
73.
74.
Julieann C. Lee Melike Pekmezci Jonathan L. Lavezo Hannes Vogel Laurence Katznelson Merav Fraenkel Griffith Harsh Mohanpal Dulai Arie Perry Tarik Tihan 《Endocrine pathology》2017,28(4):287-292
Pit-1 immunostaining is not routinely used in the characterization of pituitary adenomas, and its utility in distinguishing adenomas dedicated towards the lactotroph, somatotroph, and thyrotroph lineage from null cell adenomas warrants further evaluation. Pituitary adenomas that were negative for expression of a basic panel of hormonal markers (ACTH, prolactin, and growth hormone) were further evaluated for TSH, SF-1, and Pit-1 expression using a tissue microarray. Among the 147 identified pituitary adenomas that were negative for ACTH, prolactin, growth hormone, and TSH, expression of SF-1 was present in 68 cases (46%). Of the remaining 72 cases with sufficient tissue for further analysis, four were Pit-1 positive (6% of the adenomas negative for ACTH, prolactin, growth hormone, TSH, and SF-1); the remaining 68 were potentially null cell adenomas. Two of the Pit-1-positive adenomas displayed a paranuclear CAM 5.2 staining pattern suggestive of a sparsely granulated somatotroph adenoma; however, only one case contained fibrous bodies within a majority of the adenoma cells. Our data suggests that Pit-1 can be utilized as a second tier immunostain in cases of clinically non-functioning adenomas that are immunonegative for ACTH, prolactin, growth hormone, TSH, and SF-1 in order to further segregate rare cases of Pit-1-positive adenomas from null cell adenomas. Pit-1 immunostaining can recognize rare cases of sparsely granulated somatotroph adenomas that appear immunonegative for growth hormone, as well as rare cases of other Pit-1-positive adenomas that are negative for Pit-1 lineage hormones. Overall, pituitary adenomas of the Pit-1 lineage that do not produce prolactin, growth hormone, or TSH are rare, with only four cases identified in the current study. 相似文献
75.
Gasmelseed NM Schmidt M Magzoub MM Macharia M Elmustafa OM Ototo B Winkler E Ruge G Horstmann RD Meyer CG 《Human mutation》2004,23(2):206-207
A large proportion of non-syndromic autosomal recessive deafness (NSARD) in many populations is caused by variants of the GJB2 gene. Here, the frequency of GJB2 variants was studied in 406 and 183 apparently unrelated children from Kenya and Sudan, respectively, with mostly severe to profound non-syndromic deafness. Nine (2.2 %) Kenyan and 12 (6.6 %) of the Sudanese children only were carriers of variants within the coding sequence of the GJB2 gene. Variants in the 5'-adjacent region were detected in further 115 individuals. A total of 10 novel variants was recognized, among them four variants in the adjacent 5'-region of the GJB2 coding exon 2 (g.3318-6T>A, g.3318-15C>T, g.3318-34C>T, g.3318-35T>G), a 6 base-pair deletion (g.3455_3460del [p.Asp46_Gln48delinsGlu]), a variant leading to a stop codon (g.3512C>A [p.Tyr65X]), synonymous variants (g.3395C>T [p.Thr26], g.3503C>T [p.Asn62], g.3627A>C [p.Arg104]), and one non-synonymous variant (g.3816C>A [p.Val167Met]). In addition, the previously described variants g.3352delG (commonly designated 30delG or 35 delG), g.3426G>A [p.Val37Ile], g.3697G>A [p.Arg127His], g.3774G>A [p.Val153Ile], and g.3795G>A [p.Gly160Ser] were identified. With the exception of g.3318-34C>T and g.3352delG, all variants occurred heterozygously. For most of the variants identified in the Kenyan and Sudanese study population, a causative association with NSARD appears to be unlikely. Compared to many other ethnic groups, deafness-associated variants of the coding region of GJB2 are rare in Sudan and Kenya, suggesting a role of other genetic, or epigenetic factors as a cause for deafness in these countries. 相似文献
76.
alpha(v)beta(3) Integrin in central nervous system tumors 总被引:1,自引:0,他引:1
Lim M Guccione S Haddix T Sims L Cheshier S Chu P Vogel H Harsh G 《Human pathology》2005,36(6):665-669
alpha(v)beta(3) Is an integrin specifically expressed in endothelial cells of newly forming blood vessels. Integrin-mediated angiogenesis is hypothesized to play a central role in the development and the progression of central nervous system neoplasms. Accordingly, it is considered a potential target for antiangiogenic therapy. In the current study, we compare the expression of alpha(v)beta(3) in ependymomas, oligodendrogliomas, pilocytic astrocytomas, medulloblastomas, and vestibular schwannomas (acoustic neuromas). Samples of 5 tumors of each of the 5 tumor types were harvested surgically and frozen. After the pathological diagnosis was confirmed, immunohistochemistry was performed using an anti- alpha(v)beta(3) monoclonal antibody (LM609). The expression of alpha(v)beta(3) was assessed using a 4-tiered (0-3) grading scheme reflecting the percentage of positively staining vessels. All vestibular schwannomas demonstrated strong (grade 3) alpha(v)beta(3) expression. The expression was uniformly prominent in Antoni B regions of the tumors. Of 5 ependymomas, 4 demonstrated uniformly strong alpha(v)beta(3). Oligodendrogliomas, medulloblastomas, and pilocytic astrocytomas demonstrated more variable alpha(v)beta(3). alpha(v)beta(3) may contribute significantly to angiogenesis in vestibular schwannomas and ependymomas. Despite the high vascular density of oligodendrogliomas, pilocytic astrocytomas, and medulloblastomas, these tumors had variable moderate alpha(v)beta(3) expression. This discrepancy suggests temporal and/or regional variability in the angiogenesis in these types of tumor. This study provides the first demonstration of alpha(v)beta(3) expression in vestibular schwannomas, medulloblastomas, and pilocytic astrocytomas. 相似文献
77.
p63 deficiency activates a program of cellular senescence and leads to accelerated aging 总被引:7,自引:0,他引:7
The p53 tumor suppressor plays a key role in organismal aging. A cellular mechanism postulated to drive the aging process is cellular senescence, mediated in part by p53. Although senescent cells accumulate in elderly individuals, most studies have relied on correlating in vitro senescence assays with in vivo phenotypes of aging. Here, using two different mouse models in which the p53-related protein p63 is compromised, we demonstrate that cellular senescence and organismal aging are intimately linked and that these processes are mediated by p63 loss. We found that p63(+/-) mice have a shortened life span and display features of accelerated aging. Both germline and somatically induced p63 deficiency activates widespread cellular senescence with enhanced expression of senescent markers SA-beta-gal, PML, and p16(INK4a). Using an inducible tissue-specific p63 conditional model, we further show that p63 deficiency induces cellular senescence and causes accelerated aging phenotypes in the adult. Our results thus suggest a causative link between cellular senescence and aging in vivo, and demonstrate that p63 deficiency accelerates this process. 相似文献
78.
Józef Dulak Agnieszka Loboda Agnieszka Jazwa Anna Zagorska Jacob D?rler Hannes Alber Wolfgang Dichtl Franz Weidinger Matthias Frick Alicja Jozkowicz 《Endothelium》2005,12(5-6):233-241
The pleiotropic effects of statins, inhibitors of 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase, have been recently extended to the modulation of angiogenesis. Here, to get more insight into the statins action, the authors have investigated the effect of atorvastatin on the expression of several angiogenic and inflammatory genes in human umbilical endothelial cells (HUVECs). Atorvastatin was proangiogenic at the dose of 10 nM, and antiangiogenic at the concentrations of 1 to 10 micro M. Moreover, these higher concentrations inhibited also the proliferation of HUVECs induced by vascular endothelial growth factor (VEGF). Lower doses of atorvastatin did not influence endothelial cell proliferation. Importantly, atorvastatin at the micromolar concentrations diminished the production of interleukin (IL)-8, a proinflammatory and proangiogenic chemokine, and inhibited the synthesis of urokinase plasminogen activator (uPA), a potent proinflammatory mediator. However, it decreased also the expression of plasminogen activator inhibitor-1 (PAI-1) and thrombospondin-1 (TSP-1), the inhibitors of angiogenesis. Atorvastatin stimulated the expression of angiopoietin (Ang)-2 and moderately enhanced the expression of endothelial nitric oxide synthase (eNOS), whereas heme oxygenase-1 (HO-1) was not significantly affected. In conclusion, the present findings points to other angiogenesis-related effects of atorvastatin, which may be of relevance to the beneficial influence of statins in cardiovascular system. 相似文献
79.
Were we erring? The impact of worry and arousal on error-related negativity in a non-clinical sample
Kai Härpfer Hannes Per Carsten Daniel Spychalski Norbert Kathmann Anja Riesel 《Psychophysiology》2020,57(11):e13661
The monitoring of one's own actions allows humans to adjust to a changing and complex world. Previous neuroscientific research found overactive action monitoring and increased sensitivity to errors to be associated with anxiety and it is assumed to contribute to the development and maintenance of anxiety symptoms. A largely shared decomposition of anxiety differentiates two dimensions: anxious apprehension (i.e., worry) and anxious arousal (i.e., physiological hyperarousal). Alterations in neural correlates of error monitoring have been more closely linked to anxious apprehension compared to anxious arousal. This study examined the relationship between anxiety dimensions and electrophysiological correlates of action monitoring (i.e., error-related negativity, ERN, and correct-response negativity, CRN). A total of 135 non-clinical participants performed a flanker task while their electroencephalogram was recorded. We recruited participants with converging and diverging anxiety dimension profiles (i.e., above or below median in anxious apprehension and anxious arousal or above median in one and below in the other dimension). This grouping strategy facilitates disentangling possible interactions and allows the investigation of the isolated effect of each anxiety dimension. Regression analyses did not reveal a significant main or interaction effect of anxiety dimensions on ERN or CRN, irrespective of gender. In addition, Bayesian statistical analyzes yielded evidence for the absence of an association between both anxiety dimensions and ERN and CRN. Altogether, our results suggest that the association of anxiety dimensions, particularly anxious apprehension, and action monitoring might be smaller in non-clinical samples as previous studies indicate. 相似文献
80.
Du P Ye L Li H Ruge F Yang Y Jiang WG 《International journal of molecular medicine》2012,29(3):428-434
Growth differentiation factor-9 (GDF-9) is a family member of bone morphogenetic proteins (BMPs), which belong to the TGF-β superfamily. There has been a recent surge of interest in the role of growth differentiation factors and other BMPs in the development and spread of cancer. However, the role of GDF-9 in bladder cancer remains unknown. The present study investigated the expression of GDF-9 in normal and malignant human bladder tissue and its molecular interactions within bladder cancer cells. The expression of GDF-9 in human bladder tissues and bladder cancer cell lines was assessed at both the mRNA and protein levels using RT-PCR and immunohistochemistry, respectively. Full-length GDF-9 cDNA was amplified from normal mammary tissues. GDF-9 was overexpressed in bladder cancer cell lines using a mammalian expression construct. The effect of GDF-9 on cellular functions, was examined in bladder cancer cells overexpressing GDF-9 using a variety of in vitro assays. In normal bladder tissues, stronger staining of GDF-9 was seen in transitional cells, both in the cytoplasm and in the nucleus. In contrast, the staining of GDF-9 was notably weak or absent in cancer cells of tumour tissues. Similarly, the bladder cancer cell lines RT112 and EJ138, expressed very low levels of GDF-9. Moreover, overexpression of GDF-9 reduced the growth, adhesion and migration of bladder cell lines in vitro. However, the overexpression of GDF-9 had little bearing on the invasion of bladder cell lines in vitro. In conclusion, GDF-9 is expressed at lower levels in human bladder cancer cells compared with normal transitional cells of the bladder. GDF-9 levels are inversely correlated with the growth, adhesion and migration of bladder cancer cells in vitro. The results of the present study suggest that GDF-9 is a potential tumour suppressor in human bladder cancer. 相似文献