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991.
The prevalence of single and multiple HPV infections was assessed over a cohort of 213 women with cytological abnormalities and its association with cervical neoplasia established. Roche linear array HPV genotyping test was used to identify HPV genotypes. The most prevalent HPV genotypes in cervical cancer samples were HPV16 (61.2%), HPV52 (16.1%), HPV18 (12.9%) and HPV 31 (9.6%). Multiple HR and LR HPV infections, comprising between two and 5+ HPV types, were identified in 49.7% of samples, with a significantly lower number in severe dysplasia and cervical cancer samples (p<0.05). These results seem to indicate that detection of multiple HPV infection with HR-HPV types is not significantly better as a predictor of cervical cancer than single HR-HPV infection, though further longitudinal studies are needed to better clarify the relevance of these infections to the progression of cervical neoplasia.  相似文献   
992.
Functional magnetic resonance imaging (fMRI) is used to distinguish areas of the brain responsible for different tasks and functions. It is possible, for example, by using fMRI images, to identify particular regions in the brain which can be considered as "functional organs at risk" (fOARs), i.e., regions which would cause significant patient morbidity if compromised. The aim of this study is to propose and validate a method to exploit functional information for the identification of fOARs in CyberKnife (Accuray, Inc., Sunnyvale, CA) radiosurgery treatment planning; in particular, given the high spatial accuracy offered by the CyberKnife system, local nonrigid registration is used to reach accurate image matching. Five patients affected by arteriovenous malformations (AVMs) and scheduled to undergo radiosurgery were scanned prior to treatment using computed tomography (CT), three-dimensional (3D) rotational angiography (3DRA), T2 weighted and blood oxygenation level dependent echo planar imaging MRI. Tasks were chosen on the basis of lesion location by considering those areas which could be potentially close to treatment targets. Functional data were superimposed on 3DRA and CT used for treatment planning. The procedure for the localization of fMRI areas was validated by direct cortical stimulation on 38 AVM and tumor patients undergoing conventional surgery. Treatment plans studied with and without considering fOARs were significantly different, in particular with respect to both maximum dose and dose volume histograms; consideration of the fOARs allowed quality indices of treatment plans to remain almost constant or to improve in four out of five cases compared to plans with no consideration of fOARs. In conclusion, the presented method provides an accurate tool for the integration of functional information into AVM radiosurgery, which might help to minimize undesirable side effects and to make radiosurgery less invasive.  相似文献   
993.
We report on 2 composite lymphomas occurring in elderly patients, morphologically characterized by the combination of peripheral T-cell lymphoma (PTCL) unspecified and B-cell small lymphocytic lymphoma. Immunohistochemistry provided objective confirmation of the coexistence of the 2 malignancies, as did molecular biology by revealing clonal T-cell receptor gamma and immunoglobulin heavy chain gene rearrangements. One of the patients had no history of indolent lymphoma either at the personal and family level, whereas the other showed a strong familial predisposition, his mother and sister having suffered from B-cell chronic lymphocytic leukemia. Epstein-Barr virus was detected in the PTCL component of 1 case, but was negative in the other. To the best of our knowledge, the simultaneous occurrence of PTCL unspecified and B-cell small lymphocytic lymphoma is an exceptional event; the possible pathogenetic correlations between the 2 neoplasms are discussed.  相似文献   
994.
995.

Background

A limited number of studies aimed at investigating the possible association of Y‐chromosome haplogroups with microdeletions of the azoospermia factors (AZFs) or with particular infertile phenotypes, but definitive conclusions have not been attained. The main confounding elements in these association studies are the small sample sizes and the lack of homogeneity in the geographical origin of studied populations, affecting, respectively, the statistical power and the haplogroup distribution.

Materials and methods

To assess whether some Y‐chromosome haplogroups are predisposing to, or protecting against, azoospermia factor c (AZFc; b2/b4) deletions, 31 north Italian patients carrying the AZFc b2/b4 microdeletion were characterised for 8 Y‐chromosome haplogroups, and compared with the haplogroup frequency shown by a north Italian population without the microdeletion (n = 93).

Results and discussion

A significant difference was observed between the two populations, patients with microdeletions showing a higher frequency of the E haplogroup (29.3% vs 9.7%, p<0.01). The geographical homogeneity of the microdeleted samples and of the control population, controlled at microgeographical level, allows the possibility that the geographical structure of the Y genetic variability has affected our results to be excluded.

Conclusion

Thus, it is concluded that in the north Italian population Y‐chromosome background affects the occurrence of AZFc b2/b4 deletions.Y‐chromosome long‐arm microdeletions are found in 5–10% of men with severe oligospermia and non‐obstructive azoospermia, and encompass one or more azoospermia factor (AZF) loci. Deletions of the azoospermia factor c (AZFc) region are clearly among the most commonly known molecular causes of spermatogenic failure in men.1 These deletions are caused by homologous recombination between the 229‐kb‐long b2 and b4 amplicons2 and span 3.5 Mb. Eight different gene families are removed by AZFc deletions, including all members of the DAZ gene family, which represents the stronger candidate for the AZFc phenotype.1,2,3,4,5,6,7 Although all AZFc deletions are essentially identical in molecular extension, people carrying these microdeletions present variable infertile phenotypes, suggesting the involvement of environmental factors and/or other genetic regions. Furthermore, the function of the AZF genes in human spermatogenesis and the role of the Y‐chromosome background in the predisposition to occurrence of deletions is still largely unknown.At present, around 250 Y single‐nucleotide polymorphisms have been discovered and their phylogenetic relationships are well known.8 These polymorphic markers of the male‐specific region of the Y chromosome define monophyletic groups of the Y chromosome, which hereafter we will name as “haplogroups”.A limited number of studies have investigated the possible association of Y‐chromosome haplogroups with microdeletions or with a particular infertile phenotype,9 but the contribution of predisposing factors or genetic background to causing deletions is still debated. In particular, only three studies have investigated the possible association between Y‐chromosome haplogroups and AZF deletions,10,11,12 all of them failing to establish important associations. These works studied such associations in an European population involving 73 microdeleted samples of heterogeneous geographical origin,10 in a northwestern European population involving 50 patients11 and in a Japanese population, more geographically localised but represented by a very low number of people with microdeletions (six patients).12 All the previous studies that found some suggestion of an association with Y‐chromosome haplogroups dealt with infertility. They reported a considerable over‐representation of the haplogroup K(xL,N,O1,O3c,P) in Danish men with reduced sperm count, which did not reach significance probably because of a small sample size,13 and D2b Y lineage in Japanese men with reduced sperm count,14 not confirmed by a later study.12However, these association studies require particular attention to two principal factors: (1) the geographical structure of the Y‐chromosome variations in the population under investigation, because the Y‐chromosome genetic variability is highly geographically structured and the Y‐haplogroup distribution changes over different geographical areas15; and (2) the number and selection criteria of the patient and control groups.To assess whether some Y‐chromosome haplogroups predispose to, or protect against, AZFc deletion, we have defined and compared Y‐chromosome haplogroup distribution in a group of unrelated Italian infertile men harbouring the b2/b4 deletion (n = 41, 31 of whom were from north Italy) and in a control group represented by fertile men without microdeletions (fathers of at least one child) from north Italy (n = 93).  相似文献   
996.
A novel single-nucleotide deletion in exon 100 of the RYR1 gene, corresponding to deletion of nucleotide 14,510 in the human RyR1 mRNA (c14510delA), was identified in a man with malignant hyperthermia and in his two daughters who were normal for malignant hyperthermia. This deletion results in a RyR1 protein lacking the last 202 amino acid residues. All three subjects heterozygotic for the mutated allele presented with a prevalence of type 1 fibres with central cores, although none experienced clinical signs of myopathy. Expression of the truncated protein resulted in non-functional RYR1 calcium release channels. Expression of wild-type and RyR1(R4836fsX4838) proteins resulted in heterozygotic release channels with overall functional properties similar to those of wild-type RyR1 channels. Nevertheless, small differences in sensitivity to calcium and caffeine were observed in heterotetrameric channels, which also presented an altered assembly/stability in sucrose-gradient centrifugation analysis. Altogether, these data suggest that altered RYR1 tetramer assembly/stability coupled with subtle chronic changes in Ca2+ homoeostasis over the long term may contribute to the development of core lesions and incomplete malignant hyperthermia susceptibility penetrance in individuals carrying this novel RYR1 mutation.  相似文献   
997.
998.
999.
Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by the emergence of autoreactive T cells. Humans and mice with SLE have reduced numbers of CD1d-restricted invariant natural killer T (iNKT) cells, suggesting a key role for these cells in its immunopathogenesis. This subset uses an invariant TCR constituted by Valpha14 Jalpha281 chains paired with some Vbeta domains. The regulatory role for iNKT cells in non-autoimmune mice was suggested by our previous results showing that aged Jalpha281 knockout (KO) mice produce anti-dsDNA. Here we show that old Jalpha281 KO mice have proteinuria and antibodies against dsDNA and cardiolipin. Histological analysis of Jalpha281 KO mice revealed glomeruli damage and deposition of C3c and IgG, mainly of the IgG3 subclass. In spleens of aged Jalpha281 KO mice there is an increase of activated marginal zone B cells. The evolution of lesions may depend on the age-associated increase of autoantibodies production, preferentially IgG3, mainly secreted by marginal zone B cells. Our results provide the first evidence of a lupus-like syndrome in non-autoimmune mice, supporting an age-related immunoregulatory role of Jalpha281+ cells, probably associated with the activation of marginal zone B cells.  相似文献   
1000.
Revision total knee arthroplasty (RTKA) is a skill-demanding intervention presenting several technical challenges to the surgeon due to bone deficiencies and lack of anatomical references. Computer-assisted navigation systems can potentially solve these problems. An innovative computer-assisted surgical technique for RTKA is presented. The system is image free. Based on anatomical landmarks acquired on the patient, the system automatically plans the intervention, and provides the surgeon with tools to analyse and modify the proposed plan and to accurately reproduce it on the patient. Although we performed few cases with this navigated procedure, early results obtained demonstrated to be very promising.  相似文献   
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