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41.
Background: The differential tolerability profile of various interferon (IFN)-α preparations used in combination with ribavirin for the treatment of chronic hepatitis C needs to be elucidated. Approximately 8% of patients receiving recombinant IFNα-2b plus ribavirin discontinue treatment because of adverse events. Human leucocyte IFNα is deemed to have a better safety profile than recombinant IFNα. We therefore compared the safety profile and efficacy of ribavirin combined with leucocyte IFNα or with recombinant IFNα-2b in treatment-naive patients with chronic hepatitis C. Study design: We randomised 423 patients to either leucocyte IFNα 3MU three times weekly plus ribavirin (210 patients) or the same dose of recombinant IFNα-2b plus ribavirin (213 patients). Patients were treated for 24 weeks and followed-up for a further 48 weeks. The primary endpoint was the safety profile of the two therapies; the secondary endpoint was the rate of sustained response. Results: In patients receiving leucocyte IFNα, the total number of adverse events was lower than in the group receiving recombinant IFNα (259 vs 441 patients), and the percentage of patients discontinuing treatment because of adverse events or laboratory abnormalities was significantly reduced (4% vs 11%; p = 0.013). Sustained response was observed in 47% of patients receiving leucocyte IFNα plus ribavirin and in 44% of patients receiving IFNα-2b plus ribavirin. Conclusions: Both therapeutic regimens were effective in inducing a sustained response in naive patients. However, the safety profile of leucocyte IFNα plus ribavirin was more favourable than that observed with the administration of recombinant IFNα-2b plus ribavirin, suggesting that leucocyte IFNα may be an alternative option in patients with reduced tolerability to other IFNs.  相似文献   
42.
We describe a large inbred Sicilian family that includes four 46, XX (SRY-) brothers. Palmoplantar hyperkeratosis (PPK) and an associated predisposition to squamous cell carcinoma (SCC) of the skin, segregates as a recessive trait within the family. Interestingly, all the PPK-affected members of the family are phenotypic males (46,XY or 46,XX) while seven XX sibs are healthy phenotypic females with no signs of PPK. We propose that homozygosity for a single mutational event, possibly including contiguous genes, may cause PPK/SCC in both XY or XX individuals and sex reversal in XX individuals. The family is informative for linkage analysis for the PPK trait and allows linkage exclusion for the sex reversal trait. Here we show that 15 loci involved in PPK etiology, skin differentiation, function or malignancy, and nine loci involved in sex determination/differentiation are not implicated in the phenotype of this family.  相似文献   
43.
44.
We investigated 27 pleomorphic carcinomas of the lung for exon 1 K-ras gene mutations using polymerase chain reaction-single-strand conformation polymophism analysis and direct sequencing. All pleomorphic carcinomas were biphasic, that is, composed of an adeno-, squamous- or large-cell-carcinomatous component associated with a spindle- and/or giant-cell component. Of 27 cases, six (22%) showed K-ras codon 12 mutations, which is a figure higher than that previously reported on in pure sarcoma-like pleomorphic carcinomas. Five tumors displayed the same mutation in both the epithelial and the sarcomatoid components, whereas in one tumor the mutation was restricted to the epithelial component. All mutations occurred in smokers, and were transversions, including GGT (glycine) to TGT (cysteine) change in two cases, to GCT (alanine) in two and to GTT (valine) in two. No significant relationships were found between the occurrence and type of mutations and patients' survival or any other clinicopathological variable, suggesting that K-ras mutations are early events in the development of these tumors. Our results indicate that most, though not all, biphasic pleomorphic carcinomas of the lung are monoclonal in origin, and that cigarette smoking may have a causative role in the development of K-ras alterations in these tumors, as all mutations are transversions.  相似文献   
45.
Although the haemagglutination inhibition assay is considered the "gold standard" for antigenic characterisation of influenza viruses, some limitations of this technique are well known. A new microneutralisation assay, as a tool for antigenic characterisation of influenza B viruses, has been standardised and its performance evaluated in comparison with the haemagglutination inhibition test in the light of molecular characterisation of the haemagglutinin. Twelve B viruses belonging to the two lineages and the four sub-lineages discriminated by phylogenetic analysis of HA were tested. The microneutralisation assay clearly distinguishes viruses belonging to different lineages and, in addition, discriminates strains belonging to different sub-lineages that are poorly or not discriminated using the haemagglutination inhibition test. This new microneutralisation assay could provide a useful tool for antigenic characterisation of circulating influenza viruses and contribute, together with the haemagglutination inhibition test and sequence analysis of the haemagglutinin and neuraminidase, in the choice of the strain for use in vaccine composition.  相似文献   
46.
The distribution of intrinsic components (Laminin and Type IV Collagen) and extrinsic component (Fibronectin) of the Basement Membrane (BM) has been studied in normal uterine cervix (16 cases), in cervical dysplasia (14 cases) and in invasive carcinoma (45 cases). We found that BM staining for Laminin and Type IV collagen is linear and continuous underlying normal and dysplastic epithelium (CIN 1-CIN 2), it shows minor breaks in continuity and alterations of linearity in situ carcinomas (CIN 3), and it disappears in microinvasive areas. In well differentiated invasive carcinomas only focal disruptions of BM around neoplastic nests is noted; in contrast, in moderately and poorly differentiated neoplasias, is found a progressive reduction and loss of staining for Laminin and Type IV Collagen. The results of this study suggest that the distribution patterns of BM intrinsic components are in relation to the histological grade of cervical neoplasias and their invasion ability. On the contrary Fibronectin doesn't show any distribution pattern related to the grade of cervical neoplasias, its immunostaining increased with the rise of both connective tissue stroma production and of vascularity.  相似文献   
47.
The pterion is one of the most interesting bone meeting points in craniofacial osteology and its complex morphology derives from the fact that is the contact point of the facial skeletal elements, skull base and calvarium. Knowledge of its peculiar morphology is mandatory for the pterional approach used in microsurgery and surgery. The Authors studied 506 adult, human skulls where the pterion was accurately reconstructed on polyethylene sheets. They report their data on the morphological analysis and classify the forms. They focussed their attention on the presence of wormian bones at the level of the sphenoparietal suture, on the peculiar existing morphology and reviewed the literature on these classifications. The Authors also evaluated the length of the sphenoparietal suture, the minimum gap between the frontal and temporal, the influence of pteric bones on pterion variability and any correlations between measurements and cranial indexes.  相似文献   
48.
Neuropathological diagnostic criteria for Creutzfeldt-Jakob disease (CJD) and other human transmissible spongiform encephalopathies (prion diseases) are proposed for the following disease entities: CJD - sporadic, iatrogenic (recognised risk) or familial (same disease in 1st degree relative): spongiform encephalopathy in cerebral and/or cerebellar cortex and/or subcortical grey matter; or encephalopathy with prion protein (PrP) immuno-reactivity (plaque and/or diffuse synaptic and/or patchy/perivacuolar types). Gerstmann-Sträussler-Scheinker disease (GSS) (in family with dominantly inherited progressive ataxia and/or dementia): encephalo(myelo)pathy with multicentric PrP plaques. Familial fatal insomnia (FFI) (in member of a family with PRNP178 mutation): thalamic degeneration, variable spongiform change in cerebrum. Kuru (in the Fore population). Without PrP data, the crucial feature is the spongiform change accompanied by neuronal loss and gliosis. This spongiform change is characterised by diffuse or focally clustered small round or oval vacuoles in the neuropil of the deep cortical layers, cerebellar cortex or subcortical grey matter, which might become confluent. Spongiform change should not be confused with non-specific spon-giosis. This includes status spongiosus (“spongiform state”), comprising irregular cavities in gliotic neuropil following extensive neuronal loss (including also lesions of “burnt-out” CJD), “spongy” changes in brain oedema and metabolic encephalopathies, and artefacts such as superficial cortical, perineuronal, or perivascular vacuolation; focal changes indistinguishable from spongiform change may occur in some cases of Alzheimer's and diffuse Lewy body diseases. Very rare cases might not be diagnosed by these criteria. Then confirmation must be sought by additional techniques such as PrP immunoblotting, preparations for electron microscopic examination of scrapie associated fibrils (SAF), molecular biologic studies, or experimental transmission.  相似文献   
49.
The present study was aimed at the anatomical identification in the rat of neurons of the lower brainstem reticular formation which give off axonal branches ascending bilaterally to more rostral structures and descending unilaterally to the spinal cord. Three fluorescent tracers were injected in one and the same animal. Fast Blue was injected in the midbrain tegmentum, in the termination areas and fiber bundles of the ascending reticular efferents; Evans blue was injected in the midbrain tegmentum on the other side; either Nuclear Yellow or Diamidino Yellow was injected in the white and gray matter of the upper cervical cord. All three populations of single-labeled cells, as well as double labeled either from the midbrain injections or from the ipsilateral injections in the mesencephalon and spinal cord, were intermingled in the medial reticular formation. Very few cells double labeled from the contralateral mesencephalon and ipsilateral spinal cord were also seen. However, the main finding of the present study was the visualization of triple-labeled cells. The latter were mainly located ipsilaterally to the injections in the spinal cord. The present results indicate that reticular cells give off divergent multiple branches descending to the ipsilateral spinal cord and ascending bilaterally to rostral centers.  相似文献   
50.
Dysfunction of neutrophils (polymorphonuclear leukocytes [PMNL]) and macrophagic cells occurs as a consequence of human immunodeficiency virus type 1 (HIV-1) infection. Macrophages contribute to the resolution of early inflammation ingesting PMNL apoptotic bodies. This study investigated macrophage ability to phagocytose PMNL apoptotic bodies in patients with HIV-1 infection in comparison with uninfected individuals and the effect of HIV Nef protein on apoptotic body phagocytosis to determine if phagocytic activity is impaired by HIV infection. Monocytes/macrophages were isolated from 10 HIV-1-infected patients and from five healthy volunteers, whereas PMNL were isolated from healthy volunteers. Macrophage phagocytosis of apoptotic PMNL was determined by staining of apoptotic bodies with fluorescein-conjugated concanavalin A or with fluorescein-labeled phalloidin. Our data show significant impairment of PMNL apoptotic body macrophage phagocytosis in subjects with HIV-1 infection presenting a concentration of CD4(+) T lymphocytes of >200/mm(3) and in particular in those with <200 CD4(+) T lymphocyte cells/mm(3). In addition, HIV-1 recombinant Nef protein is able to decrease phagocytosis of apoptotic PMNL from normal human macrophages in a dose-dependent manner. The results of our study suggest that impaired macrophage phagocytosis of PMNL apoptotic bodies may contribute to the persistence of the inflammatory state in HIV-infected subjects, especially during opportunistic infections that are often favored by defective phagocytic activity.  相似文献   
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