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21.
Guido Martignoni Maurizio Pea Matteo Brunelli Marco Chilosi Alberto Zamó Manuela Bertaso Paolo Cossu-Rocca John N Eble Gregor Mikuz Giacomo Puppa Cecile Badoual Vincenzo Ficarra Giovanni Novella Franco Bonetti 《Modern pathology》2004,17(12):1455-1463
CD10 has been considered a useful marker in the diagnosis of renal carcinomas, because of its expression in clear cell and papillary renal cell carcinomas and its absence in chromophobe renal cell carcinomas. On the other hand, chromophobe renal cell carcinoma expresses parvalbumin, which is absent in clear cell and papillary renal cell carcinomas. To further address the relevance of these markers, we studied the expression of CD10 and parvalbumin in 42 samples of chromophobe renal cell carcinoma (seven of which had aggressive features, including invasion beyond the renal capsule, renal vein invasion, metastases, or sarcomatoid transformation), 75 clear cell renal cell carcinomas (eight metastatic) and 51 papillary renal cell carcinomas (two metastatic). CD10 was found in 100% of clear cell renal cell carcinomas, 63% of papillary renal cell carcinomas and in all metastatic cases of both types. At variance with previous studies, we found CD10 expression in from 30 to 90% of the neoplastic cells, in 11 of 42 (26%) chromophobe renal cell carcinomas. The CD10-positive cases included five of the seven (71%) chromophobe renal cell carcinoma with aggressive features. Statistical analysis showed significant association of CD10-positive tumors with clinicopathologic aggressiveness (P=0.003) and mitotic figures (P=0.04). Parvalbumin was strongly expressed in all primary and metastatic chromophobe renal cell carcinomas. Western blot analysis was utilized to confirm the expression of both CD10 and parvalbumin in chromophobe renal cell carcinomas. 相似文献
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23.
A new approach for the M-typing of Streptococcus pyogenes is reported. Oligonucleotide primers were used in a PCR to amplify the N-terminal region of the emm gene. The presence of the PCR amplification product is associated with the corresponding M serotype. This technique offers potential advantages over other molecular typing methods. 相似文献
24.
Calorini L Bianchini F Mannini A Mugnai G Balzi M Becciolini A Ruggieri S 《Clinical & experimental metastasis》2002,19(3):259-264
In the present study, we found that murine peritoneal macrophages elicited by BCG or Listeria monocytogenes release into the media an activity capable of stimulating the lung colonization as well as the expression of MHC class I
antigens in B16 melanoma cells. A similar activity has previously been found in media conditioned by Corynebacterium parvum-elicited macrophages. Analysis by gel filtration chromatography of media conditioned by Corynebacterium parvum-, BCG- or Listeria monocytogenes-elicited macrophages revealed that the material responsible for the pro-clonogenic activity concentrated in chromatographic
fractions corresponding to molecular weights (25 to 52 kDa) which are characteristic of certain cytokines. Thus, we challenged
the various macrophage-conditioned media with polyclonal antibodies against IFNγand TNFα, and found that the macrophage pro-clonogenic
activity was completely abolished in the presence of anti-IFNγantibodies, but only partially inhibited by anti-TNFαantibodies.
This finding suggests a cooperative participation of the two cytokines to the pro-clonogenic activity of the media conditioned
by Corynebacterium parvum-, BCG- or Listeria monocytogenes-elicited macrophages.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
25.
Cova L Ratti A Volta M Fogh I Cardin V Corbo M Silani V 《Stem cells and development》2004,13(1):121-131
In the past few years research on stem cells has exploded as a tool to develop potential therapies to treat incurable neurodegenerative diseases. Stem cell transplantation has been effective in several animal models, but the underlying restorative mechanisms are still unknown. Several events such as cell fusion, neurotrophic factor release, endogenous stem cell proliferation, and transdifferentiation (adult cell acquisition of new unexpected identities) may explain therapeutic success, in addition to replacement of lost cells. This issue needs to be clarified further to maximize the potential for effective therapies. Preliminary stem transplantation trials have already been performed for some neurodegenerative diseases. There is no effective pharmacological treatment for amyotrophic lateral sclerosis, but recent preliminary data both in experimental and clinical settings have targeted it as an ideal candidate disease for the development of stem cell therapy in humans. This review summarizes recent advances gained in stem cell research applied to neurodegenerative diseases with a special emphasis to the criticisms put forward. 相似文献
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27.
Ultrastructural analysis of pancreatic acinar cells from mice fed on genetically modified soybean 下载免费PDF全文
Malatesta M Caporaloni C Rossi L Battistelli S Rocchi MB Tonucci F Gazzanelli G 《Journal of anatomy》2002,201(5):409-415
No direct evidence that genetically modified (GM) food may represent a possible danger for health has been reported so far; however, the scientific literature in this field is quite poor. Therefore, we investigated the possible effects of a diet containing GM soybean on mouse exocrine pancreas by means of ultrastructural, morphometrical and immunocytochemical analyses. Our observations demonstrate that, although no structural modification occurs in pancreatic acinar cells of mice fed on GM soybean, quantitative changes of some cellular constituents take place in comparison to control animals. In particular, a diet containing significant amount of GM food seems to influence the zymogen synthesis and processing. 相似文献
28.
Crotti D D'Annibale ML Ubaldi M Fonzo G Medori MC 《Le infezioni in medicina : rivista periodica di eziologia, epidemiologia, diagnostica, clinica e terapia delle patologie infettive》2002,10(4):213-219
During 2001 we analyzed 1730 pharyngeal swabs for S. pyogenes (SGA): 1142 children (0-10 years old), 132 adolescent subjects (11-17 years old), and 456 adults (18 or more years old). 994 subjects (664 children, 85 adolescent ones, 245 adults) had acute pharyngotonsillitis. In this last group we observed 321 positivities (32.3 %) for SGA: 40.4 % among children, 24.7 % among adolescent people, 13.1 % among adults. The pharyngotonsillitis prevailed during winter and spring. The resistances (R) towards erythromycin were 27.7 % (89 cases), and among children 30.6 % (82 cases), towards clyndamicin 15.3 % (49 cases, and 17.2 %, 46 cases, among children), towards rokytamicin 11.8 % (38 cases, and 13.1 %, 35 cases, among children). These were the phenotypes of R to erythromycin: 25.8 % M-phenotype, 19.1 % inducible (iMLS), 55.1 % constitutive (cMLS); among children respectively 25.6 %, 18.3 % and 53.7 %. Increased resistances towards 16-C macrolides, increased resistances of cMLS to erythromycin, and the persistence of R to 14-C macrolides around 30 % are discussed. 相似文献
29.
Cutaneous mucormycosis in a young, immunocompetent girl. 总被引:2,自引:0,他引:2
Manoel Paes de Oliveira-Neto Manuela Da Silva Paulo Cezar Fialho Monteiro Márcia Lazera Rodrigo de Almeida Paes Anna Beatriz Novellino Tulia Cuzzi 《Medical mycology》2006,44(6):567-570
We report a case of cutaneous mucormycosis in a healthy, immunocompetent young girl (age 14 years). The patient had a 5-year history of a slowly enlarging, erythematous plaque with slight elevated, scaling, circinate borders on the right thigh. Histopathology showed a granulomatous infiltrate with broad, pale, non-septate hyphae. Mycological study identified Mucor hiemalis (Wehmer). 相似文献
30.
Pietro Maria Donisi Nadia Di Lorenzo Manuela Riccardi Alessandro Paparella Claudia Sarpellon Simona Zupo Giovanni Bertoldero Claudia Minotto Vincenzo Stracca-Pansa 《Diagnostic molecular pathology》2006,15(4):206-215
We analyzed individual VH gene rearrangements in 55 consecutive B-chronic lymphocytic leukemia (B-CLL) patients collected from a northeastern region of Italy, stressing the possible differences related to geographic characteristics of the cohorts studied. Considering the percentage of somatic mutations present in the VH gene sequences and using the 98% cut-off value, 38 of the 55 B-CLL (69%) patients displayed somatic hypermutations and 17 (31%) had a germline configuration. Our results confirm and extend the observations of a bias in the use of certain VH, DH, and JH genes among B-CLL cells. The most frequently used VH genes were VH1-69 (12.7%) with VH3-23 (12.7%) and VH4-34 (10.9%). Collectively these genes accounted for 36.3% of the cases. In the mutated cases, the range of mutations varied from 2% to 15%, with a median of 6.5%. VH1-69 (7 cases, all unmutated) carried few mutations as opposed to VH3-23 (7 cases, 5 of which mutated), VH4-34 (6 cases, all mutated), and VH3-30 (5 cases, all mutated), which show a high load of mutations. D3 family genes were found frequently (38.1%) followed by D2 (27.2%) and D6 (18.1%). The individual D segment most frequently used was D3-3, which was present in 16.3% of cases. There was predominance of the JH4 gene (49%) followed by JH6 (40%). Analysis of the distribution of replacement and silent mutations in the mutated sequences using the method of Lossos showed in 39.4% of cases evidence of antigen selection in the framework region and/or complementary determining regions. In comparison with a recent study on B-CLL patients from the Mediterranean area, the VH4-34 gene was significantly overused in the mutated group at a percentage double that of the Italian cohort reported in this study (10.9% vs. 5%), but at a frequency similar to the entire Mediterranean region (10.7%). We also found an over-representation of VH1-69 usage in the germline group, at a frequency (12.7%) higher than previously described by the same authors (Italian 8%, Mediterranean 10.7%). On the contrary, VH3-07 and VH3-49 were not much used in our study (5.4% and 1.8%, respectively) compared with the Italian group (8% and 5.1%). In our study, VH3-23 gene segment was frequently expressed, at frequency as high as that of VH1-69, a finding in keeping with reported B-CLL Italian data, but higher than the entire series of the Mediterranean area (12.7% vs. 9.2%); VH3-21 gene, frequently expressed in northern European CLL but rarely in the Mediterranean area, was completely absent. This biased usage of VH family genes may reflect a geographic leukemic repertoire, perhaps owing to a peculiar genetic background, depending on variations in germline composition of the IgVH locus or to the effect of a potential environmental element less frequently encountered in different regions. 相似文献