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81.
Niggli HJ Tudisco S Privitera G Applegate LA Scordino A Musumeci F 《Journal of biomedical optics》2005,10(2):024006
Photobiological research in the last 30 yr has shown the existence of ultraweak photon emission in biological tissue, which can be detected with sophisticated photomultiplier systems. Although the emission of this ultraweak radiation, often termed biophotons, is extremely low in mammalian cells, it can be efficiently increased by ultraviolet light. Most recently it was shown that UV-A (330 to 380 nm) releases such very weak cell radiation in differentiated human skin fibroblasts. Based on these findings, a new and powerful tool in the form of UV-A-laser-induced biophotonic emission of cultured cells was developed with the intention to detect biophysical changes between carcinogenic and normal cells. With suspension densities ranging from 1 to 8 x 10(6) cells/mL, it was evident that an increase of the UV-A-laser-light induced photon emission intensity could be observed in normal as well as melanoma cells. Using this new detection procedure of ultraweak light emission, photons in cell suspensions as low as 100 microL could be determined, which is a factor of 100 lower compared to previous procedures. Moreover, the detection procedure has been further refined by turning off the photomultiplier system electronically during irradiation leading to the first measurements of induced light emission in the cells after less than 10 micros instead of 150 ms, as reported in previous procedures. This improvement leads to measurements of light bursts up 10(7) photons/s instead of several hundred as found with classical designs. Overall, we find decreasing induction ratings between normal and melanoma cells as well as cancer-prone and melanoma cells. Therefore, it turns out that this highly sensitive and noninvasive device enables us to detect high levels of ultraweak photon emission following UV-A-laser-induced light stimulation within the cells, which enables future development of new biophysical strategies in cell research. 相似文献
82.
Scotto G Saracino A El-Hamed I Iannece MD Geraci S Palumbo E Cibelli DC Angarano G 《Le infezioni in medicina : rivista periodica di eziologia, epidemiologia, diagnostica, clinica e terapia delle patologie infettive》2004,12(4):245-251
In order to retrospectively evaluate the prevalence of immigrant patients affected by active tuberculosis, we analysed the clinical data of 2255 immigrant patients hospitalised during 2002 in ordinary admission or in Day Hospital in 48 Clinics of Infectious Diseases. In all, 303 patients were affected by active tuberculosis (13.4% of the total immigrant hospitalised patients); 30 patients (9.9%) were also HIV-positive. There was a considerable male gender bias (62.5%); the mean age was 29.7 years; 144 patients were from Africa (47.5%), 72 (23.7%) from Asia, 47 (15.5%) from eastern Europe and 40 (13.2%) from South America. The clinical variants were: pulmonary (57.7%), lymph node (15.8%), meningitis (13.8%), intestinal (4.2%), bone (3.3%), pleurical (2.3%), peritoneal (2.3%) and renal (0.6%). We conclude that tuberculosis is a very frequent disease among immigrants, especially of African origin. The high percentage is due to several factors, such as no vaccine prophylaxis and poor, overcrowded living conditions. It is fundamental to focus on the need to provide better health support for all subjects by setting up screening plans to estimate the real incidence of this pathology and ensure medical treatment to prevent the spread of this infection among immigrants and the local host population. 相似文献
83.
Paglia F Dionisi S Minisola S 《The New England journal of medicine》2002,346(22):1748-9; author reply 1748-9
84.
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
85.
Human gene for proliferating cell nuclear antigen has pseudogenes and localizes to chromosome 20 总被引:5,自引:0,他引:5
De-Hui Ku Salvatore Travali Bruno Calabretta Kay Huebner Renato Baserga 《Somatic Cell and Molecular Genetics》1989,15(4):297-307
We have isolated from a human genomic library a pseudogene of the proliferating cell nuclear antigen (PCNA)gene. Its sequence shows a 78% similarity with the human PCNA/cDNA. The PCNAgene is located on human chromosome 20, while the pseudogene maps to chromosome region XpterXq13. An additional locus detected by the full-length PCNA cDNA, but not by intron probes, segregates concordantly with chromosome region 6p126pter and probably represents a second pseudogene. 相似文献
86.
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
87.
Ignazio Di Fazio Massimo Motta Salvatore Musumeci Sergio Neri Giovanni Pistone Mariano Malaguarnera 《Journal of interferon & cytokine research》2004,24(10):594-599
Determination of serum iron levels in patients affected by chronic hepatitis C is considered fundamental for studying the response to interferon-alpha (IFN-alpha) treatment. IFN could induce anemia, which is promptly corrected by exogenous administration of recombinant human erythropoietin (rHuEPO). The aim of our study was to verify the possible beneficial effect of rHuEPO in patients affected by chronic hepatitis C and treated with IFN. Seventy consecutive patients (42 males and 28 females, mean age 46.4+/-5.2 years) affected by chronic hepatitis C were enrolled. In all patients, chronic hepatitis C was diagnosed on the basis of clinical and biological findings (alanine aminotransferase [ALT] serum levels at least 2-fold higher than normal values for at least 12 months and the presence of anti-HCV antibodies). All patients were negative for hepatitis B virus (HBV) infection, hepatitis D virus (HDV infection, and HIV infection. Statistical analysis was carried out using the Wilcoxon nonparametric sum rank test, the Spearman correlation rank test, and the Friedman ANOVA and Kendall coefficient of concordance. At the end of the treatment, our study series showed significant differences in serum levels of AST (p < 0.001), iron (p < 0.001), and ferritin (p < 0.001). At the end of the follow-up period, significant differences were seen in ALT, aspartate (AST), and iron ferritin and transferrin levels. All differences favored patients who received IFN-alpha and rHuEPO. We think that the depletion of circulating iron may improve the immune response impaired by iron accumulation in the liver. Our study confirms the important role played by iron in the response to IFN treatment, suggesting that the use of rHuEPO induces a better response to IFN in patients with chronic hepatitis C by activation of erythropoiesis. 相似文献
88.
Tognon M Martini F Iaccheri L Cultrera R Contini C 《Journal of medical microbiology》2001,50(2):165-172
Neurological diseases and a variety of neoplasms frequently occur in AIDS patients. Human JC and BK polyomaviruses have been associated with neurological disorders in such patients. SV40 polyomavirus sequences have been detected in human brain tumours, other neoplasms and normal tissues. JCV, BKV and SV40 DNA sequences were investigated in cerebrospinal fluid (CSF) samples from 12 AIDS patients affected by different neurological disorders, by PCR assay and filter hybridisation with specific internal oligoprobes, and DNA sequencing. Three of the 12 CSF samples were positive for JCV (one sample) or SV40 (one) DNA, or both (one). No sample was positive for BKV DNA. JCV- and SV40-specific genomic regions were confirmed by DNA sequencing. CSF samples from the two patients diagnosed clinically as having progressive multifocal leukoencephalopathy (PML) contained either JCV (one sample) or SV40 (one) DNA. The CSF found to contain both JCV and SV40 DNA originated from a patient with a cerebral mass lesion of unknown aetiology. These results suggest that SV40 may be involved in the aetiology of PML in AIDS patients, and raise the possibility that SV40 and JCV may act synergically in vivo to enhance their pathogenicity. 相似文献
89.
90.
Pignatti P Ciapponi L Galle P Hansen MB Massa M Meazza C Paonessa G Novick D Ciliberto G Martini A De Benedetti F 《Clinical and experimental immunology》2003,131(2):355-363
We previously demonstrated that high levels of IL-6/sIL-6R complexes are present in sera of patients with systemic juvenile idiopathic arthritis (s-JIA) and that the amount of IL-6 estimated in the IL-6/sIL-6R complexes is markedly higher than that measured by the B9 assay. Here, we show that two additional bioassays, employing human myeloma XG-1 cells and human hepatoma Hep3B cells, detected serum IL-6 levels similar to those measured by the B9 assay and approximately 10-fold lower than the IL-6 levels estimated to be present in the IL-6/sIL-6R complex. Using an assay for the measurement of the amount of circulating IL-6 complexed with the sIL-6R and available for binding to gp130 (gp130 binding activity), we show that the IL-6/gp130 binding activity is similar to that detected by the bioassays and again significantly lower than that estimated to be present in the IL-6/sIL-6R complex. Addition of recombinant human IL-6 (rhIL-6) to sera of patients or controls results in a markedly lower increase in the gp130 binding activity in patients than in controls. Moreover, sera from s-JIA patients inhibited in a dose dependent manner the gp130 binding activity assay. These results show that sera from patients with s-JIA contain a factor, or factors, that inhibit(s) the binding of the IL-6/sIL-6R complex to gp130. This inhibitory activity does not appear to be due to soluble gp130, C-reactive protein or autoantibodies to IL-6. 相似文献