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61.
Terracciano LM Bernasconi B Ruck P Stallmach T Briner J Sauter G Moch H Vecchione R Pollice L Pettinato G Gürtl B Ratschek M De Krijger R Tornillo L Bruder E 《Human pathology》2003,34(9):864-871
Hepatoblastoma (HB) is the most common liver tumor in childhood and differs in its environmental risk factors and genetic background from hepatocellular carcinoma. HB is associated with inherited conditions such as familial adenomatous polyposis and Beckwith-Wiedemann syndrome, suggesting the importance of genetic abnormalities in the pathogenesis and progression of this disease. It has a very polymorphous morphology. A diverse range of cytogenetic alterations has been reported to date, the most frequent being trisomy 2 and trisomy 20. Thirty-five HB specimens from 31 patients (22 purely epithelial, 4 purely mesenchymal, 9 mixed) were examined by comparative genomic hybridization (CGH), a technique that enables us to screen the entire tumor genome for genetic losses and gains. Our aims were as follows: (1) to characterize chromosome abnormalities that appear in this tumor and (2) to identify possible differences between different histologic subtypes of HB. We found significant gains of genetic material, with very little difference in the number and type of alterations between the different histologic components of HB. The most frequent alterations were gains of Xp (15 cases, 43%) and Xq (21 cases, 60%). This finding was also confirmed by fluorescent in situ hybridization performed on nuclei extracted from 6 specimens. Other common alterations were 1p-, 2q+, 2q-, 4q-, and 4q+. We found no difference between different histologic subtypes, a finding that may be in agreement with the hypothesis of a common clonal origin for the different components. An hitherto-unreported high frequency of X chromosome gains may support the assumption that X-linked genes are involved in the development of this neoplasm. 相似文献
62.
Carolina Scagnolari Francesca Bellomi Ombretta Turriziani Francesca Bagnato Valentina Tomassini Vito Lavolpe Marilena Ruggieri Fabrizio Bruschi Giuseppe Meucci Giordano Dicuonzo Guido Antonelli 《Journal of interferon & cytokine research》2002,22(2):207-213
The frequencies of anti-interferon-beta (IFN-beta) antibody development reported to date in patients treated with different IFN-beta preparations are not readily comparable mainly because of differences in underlying diseases and assay methods. Thus, the frequency of neutralizing antibody (NAb) and binding antibody (BAb) development was analyzed in a sample of sera derived from a homogeneous group of relapsing-remitting multiple sclerosis (RRMS) patients treated with different IFN-beta preparations. The frequency of developing NAb and BAb to IFN-beta varied according to the IFN-beta given. Specifically, the NAb seroconversion frequency was significantly higher in patients treated with Betaferon, Schering AG, Berlin, Germany (31.3%) than in patients treated with both preparations of recombinant IFN-beta 1a (Rebif, Serono, Geneva, Switzerland [7.4%] or Avonex, Biogen, Cambridge, MA [6.3%]). Analysis of BAb seroconversion frequency in the same patients revealed that different IFN-beta preparations may also have different capability to induce BAb development and that BAb are produced during IFN-beta therapy at a significantly higher rate than NAb. Our main conclusion is that different human IFN-beta preparations may possess different immunogenicities, leading to varying frequency of development of antibody to IFN-beta in RRMS. 相似文献
63.
Paolo Cerretelli Bruno Grassi Lei Xi Federico Schena Claudio Marconi Michael Meyer Guido Ferretti 《European journal of applied physiology》1995,71(4):287-294
To gain an insight into the origin of the phase I ventilatory response to exercise (ph I) in humans, pulmonary ventilation WE) and end-tidal partial pressures of oxygen and carbon dioxide (P
ETO2 and P
ETCO2, respectively) were measured breath-by-breath in six male subjects during constant-intensity exercise on the cycle ergometer at 50, 100 and 150 W, with eupnoeic normocapnia (N) or hyperpnoeic hypocapnia (H) established prior to the exercise test. Cardiac output (Q2) was also determined beat-by-beat by impedance cardiography on eight subjects during moderate exercise (50 W), and the C02 flow to the lungs (Q2·CvCO2 where CvCO2 is concentration of CO2 in mixed veneous blood) was estimated with a time resolution of one breathing cycle. In N, the initial abrupt increase of PE during ph I (VE approximately 18 l · min–1 above rest) was followed by a transient fall. When P
ETCO2 started to increase (and P
ETO2 decreased) VE increased again (phase II ventilatory response, ph II). In H, during ph I VE was similar to that of N. By contrast, during ph II VE kept gradually decreasing and started to increase only when P
ETCO2 had returned to approximately 40 mmHg (5.3 kPa). Thus, as a result of the prevailing initial conditions (N or H) a temporal shift of the time-course of VE during ph II became apparent. No correlation was found between C02 flow to the lungs and VE during ph I. These results are interpreted as suggesting that an increased C02 flow to the lungs does not constitute an important factor for the initial hyperventilatory response to exercise. They are rather compatible with a neural origin of ph I, and would support the neurohumoral theory of ventilatory control during exercise. 相似文献
64.
Central precocious puberty and abnormal chromosomal patterns 总被引:1,自引:0,他引:1
Central precocious puberty (PP) can be caused by chromosomal aberrations. We report three patients presenting with central
PP in whom karyotype analysis demonstrated abnormal chromosomal patterns. The first patient was affected by the triple-X syndrome,
commonly characterized by premature ovarian failure. The second patient, a girl with inv dup(15)(pter→q12::q12→pter), had
a chromosomal aberration involving an imprinted region of the human genome, whose deletion is commonly associated with Prader-Willi
syndrome (PWS) and hypogonadotrophic hypogonadism. The third patient was a boy carrying a rare chromosome abnormality, the
duplication of chromosome 9 (q22→qter). All patients had mental retardation, which was mild in patient 1, moderate in patient
2, and severe in case 3. They underwent treatment with luteinizing hormone releasing hormone (LHRH) analogs, which were able
to stop the progression of the sexual development. We confirm that chromosomal aberrations are an important cause of central
PP, and that karyotype analysis in patients with PP and mental retardation, even if mild, is necessary because chromosomal
abnormalities can be present. 相似文献
65.
Calogero Caruso Giuseppina Candore Diego Cigna Gabriele Di Lorenzo Guido Sireci Francesco Dieli Alfredo Salerno 《Immunologic research》1996,15(1):84-90
It is well known that aging is associated with various alterations in lymphoid cell functions, particularly with a progressive decline in immune responsiveness to exogenous antigens and increasing incidence of autoimmune phenomena. Many studies have been focused on the mechanisms of the immunologic features of aging. This review describes our results of studies performed to determine the influence of age on the capacity to produce interleukin-2 (IL-2), interferon-γ (IFN-γ), interleukin-4 (IL-4), interleukin-5 (IL-5), interleukin-6 (IL-6) and tumor necrosis factor (TNF). Mitogen-stimulated cultures of mononuclear cells (MNC) from human beings were assessed for cytokine-producing capacity. A significant decrease in IFN-γ and IL-2 production by MNC cultures from elderly individuals was observed. No significant difference was instead observed between cultures from elderly individuals and those from young ones as regards TNF-α, IL-4 and IL-6 production. Mitogen or antigen-stimulated cultures of MNC from aged mice also displayed a significant decrease in IFN-γ and IL-2 production as well as TNF-β. Instead IL-4 and IL-5 production significantly increased in these cultures. We suggest that this imbalanced cytokine production may well account for the pattern of immune response which may be observed in the elderly, i.e. a normal or increased humoral response (including autoimmune responses) in face of a low T cell immune responsiveness. 相似文献
66.
Dendritic cells (DC) and natural killer (NK) cells, the main cellular components of the innate immune system, participate
in the most ancient first line of defense against infections. Both types of cells patrol peripheral tissues, whereas their
rapid recruitment and activation at mucosal surfaces [the major entry point for the human immunodeficiency virus (HIV)] is
a hallmark of acute inflammatory response. The ability of HIV to survive and replicate in the human host relies upon several
molecular mechanisms eluding the immune surveillance of both adaptive immunity and of DC and NK cells beginning with the acute
phase of primary HIV infection. DC and NK cells, unlike CD4+ T cells, are impaired more functionally rather than being depleted by HIV infection.
In this article we will review some of the aspects of DC/NK cells interaction with HIV infection both in vitro and in vivo,
and we will also speculate on the potential consequence for HIV pathogenesis and for the capacity of the virus to escape the
surveillance of the innate immune system. 相似文献
67.
Grosso S Vivarelli R Muraca MC Berardi R Marconcini S Morgese G Balestri P 《American journal of medical genetics. Part A》2004,(3):300-302
Craniofacial dyssynostosis (CFD) is a rare disorder related to premature closure of the lambdoid suture and the posterior part of the sagittal suture. Epilepsy, mental retardation, abnormalities of the corpus callosum, and short stature have been reported. We studied a patient with CFD, hydronephrosis, and partially empty sella turcica; the latter two features are reported for the first time. We discuss the brain anomalies and their neurologic sequelae, which are part of the CFD phenotype. 相似文献
68.
Reciprocal stimulation of gammadelta T cells and dendritic cells during the anti-mycobacterial immune response 总被引:2,自引:0,他引:2
Dieli F Caccamo N Meraviglia S Ivanyi J Sireci G Bonanno CT Ferlazzo V La Mendola C Salerno A 《European journal of immunology》2004,34(11):3227-3235
Gammadelta T cells and dendritic cells (DC) are two distinct cell types of innate immunity that participate in early phases of immune response against Mycobacterium tuberculosis infection. Here we show that a close functional relationship exists between these cell populations. Using an in vitro coculture system, Vgamma1 T cells from Tcrb(-/- )mice were found to be activated by DC infected in vitro with BCG, as indicated by the elevated CD69 expression, IFN-gamma secretion and cytotoxic activity. This activation process was due to a non-cognate mechanism since it required neither cell to cell contact nor interaction between the TCR and a specific antigen, but was mediated by DC-derived IL-12. Reciprocally, Vgamma1 T cells provided a key cytokine, IFN-gamma, which increased IL-12 production by BCG-infected DC. Moreover, exposure of BCG-infected DC to Vgamma1 T cells conditioned the former to prime a significantly stronger anti-mycobacterial CD8 T cell response. Consequently, stimulation of gammadelta T cells and their non-cognate interaction with DC could be applied as an immune adjuvant strategy to optimize vaccine-induced CD8 T cell immunity. 相似文献
69.
70.
Lugli A Forster Y Haas P Nocito A Bucher C Bissig H Mirlacher M Storz M Mihatsch MJ Sauter G 《Human pathology》2003,34(10):994-1000
Calretinin is a calcium-binding protein expressed in different normal and neoplastic tissues. Early studies suggested that calretinin is a useful marker to differentiate adenocarcinomas from malignant mesotheliomas of the lung, but subsequent work has shown that calretinin can be expressed in several other tumor types. To systematically investigate the epidemiology of calretinin expression in normal and neoplastic tissues, we used tissue microarrays (TMAs) to analyze the immunohistochemically detectable expression of calretinin in 5233 tissue samples from 128 different tumor categories and 76 different normal tissue types. At least 1 case with weak expression could be found in 74 of 128 (58%) different tumor types and 46 entities (36%) had at least 1 tumor with strong positivity. In normal tissues, a particularly strong expression was found in Leydig cells of the testis, neurons of the brain, theca-lutein and theca interna cells of the ovary, and mesothelium. In tumors, strong calretinin expression was most frequently found in malignant mesotheliomas (6 of 7), Leydig cell tumors of the testis (5 of 5), adenomas of adrenal gland (5 of 9), and adenomatoid tumors (4 of 9). In summary, calretinin is frequently expressed in many different tumor types. Metastases of various different origins must be included in the differential diagnosis of calretinin-positive pleura tumors. 相似文献