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To investigate the genetic contribution to familial similarity in longevity, we set up a novel experimental design where cousin-pairs born from siblings who were concordant or discordant for the longevity trait were analyzed. To check this design, two chromosomal regions already known to encompass longevity-related genes were examined: 6p21.3 (genes TNFalpha, TNFbeta, HSP70.1) and 11p15.5 (genes SIRT3, HRAS1, IGF2, INS, TH). Population pools of 1.6, 2.3 and 2.0 million inhabitants were screened, respectively, in Denmark, France and Italy to identify families matching the design requirements. A total of 234 trios composed by one centenarian, his/her child and a child of his/her concordant or discordant sib were collected. By using population-specific allele frequencies, we reconstructed haplotype phase and estimated the likelihood of Identical By Descent (IBD) haplotype sharing in cousin-pairs born from concordant and discordant siblings. In addition, we analyzed haplotype transmission from centenarians to offspring, and a statistically significant Transmission Ratio Distortion (TRD) was observed for both chromosomal regions in the discordant families (P=0.007 for 6p21.3 and P=0.015 for 11p15.5). In concordant families, a marginally significant TRD was observed at 6p21.3 only (P=0.06). Although no significant difference emerged between the two groups of cousin-pairs, our study gave new insights on the hindrances to recruiting a suitable sample to obtain significant IBD data on longevity-related chromosomal regions. This will allow to dimension future sampling campaigns to study-genetic basis of human longevity.  相似文献   
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Prostate and breast cancer are major causes of death worldwide, mainly due to patient relapse upon disease recurrence through formation of metastases. Chemokines are small proteins with crucial roles in the immune system, and their regulation is finely tuned in early inflammatory responses. They are key molecules during inflammatory processes, and many studies are focusing on their regulatory functions in tumor growth and angiogenesis during metastatic cell seeding and spreading. Bindarit is an anti-inflammatory indazolic derivative that can inhibit the synthesis of MCP-1/CCL2, with a potential inhibitory function in tumor progression and metastasis formation. We show here that in vitro, bindarit can modulate cancer-cell proliferation and migration, mainly through negative regulation of TGF-β and AKT signaling, and it can impair the NF-κB signaling pathway through enhancing the expression of the NF-κB inhibitor IkB-α. In vivo administration of bindarit results in impaired metastatic disease in prostate cancer xenograft mice (PC-3M-Luc2 cells injected intra-cardially) and impairment of local tumorigenesis in syngeneic Balb/c mice injected under the mammary gland with murine breast cancer cells (4T1-Luc cells). In addition, bindarit treatment significantly decreases the infiltration of tumor-associated macrophages and myeloid-derived suppressor cells in 4T1-Luc primary tumors. Overall, our data indicate that bindarit is a good candidate for new therapies against prostate and breast tumorigenesis, with an action through impairment of inflammatory cell responses during formation of the tumor-stroma niche microenvironment.  相似文献   
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Objective

The benefits of prostate-specific antigen (PSA)–based prostate cancer screening are controversial. We sought to determine the change in prostate cancer presentation coinciding with the release of the United States Preventative Services Task Force recommendations against screening in a high-volume community-based urology practice.

Methods

Characteristics of men presenting for an elevated PSA at a community urology practice from August 2011 to August 2015 were queried from a prospectively collected database. A retrospective analysis of presenting PSA, Gleason grade at biopsy, and prostatectomy as well as clinical and pathologic stage was performed. Kruskal-Wallis rank sum and chi-square tests were used for analysis.

Results

Referrals for elevated PSA decreased from 933 in year 1 to 816 by year 4 (12.5% decrease) with a concomitant reduction in biopsies performed in newly referred men from 461 to 356 (22.8% decrease, P = 0.02). The proportion of men presenting with PSAs>10 increased from 28.1% to 36.8% (P = 0.009). First-time biopsy-positivity rate increased from 48.4% to 62.4% with a rise in the proportion having Gleason≥7 from 51.6% to 69.7% (P = 0.0001). Of the 578 men who underwent radical prostatectomy, there was a 19.4% increase in Gleason≥7 tumors (P = 0.01).

Conclusions

Our findings demonstrate a decrease in elevated PSA referrals, increase in PSA at the time of referral, decrease in detection of low-risk disease, and increase in detection of intermediate-/high-risk disease in a high-volume, multisite, community-based urology practice, coinciding with the United States Preventative Services Task Force recommendations against PSA screening.  相似文献   
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In this article, we report a 65-year-old man with a large atrial myxoma arising from the posterior wall and from the base of the right inferior pulmonary vein. The big neoplastic mass showed a large implant site. A rare atrial myxoma neovascularity arising from the atrial circumflex artery was very clearly visualized by selective coronary arteriography. The surgical approach used to resect this tumor was an isolated left atriotomy that provided excellent exposure and safe excision.  相似文献   
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Gerontology research carried out in different scientific centers of Georgia follows the basic directions of most work in this field: epidemiology, investigation of the mechanisms of aging, and finding ways to prevent senile pathologies and to prolong life. The genealogy and epidemiology of long-living peaple have been studied in areas with high occurrence of these people by considering the sex ratio and social status of the long-living, the influence of environmental factors, and the development of senile pathologies. According to the centrosome (centriole) model of aging, the centrosomes and the cytoskeleton, important structures in cellular differentiation and morphogenesis, may be involved in the initiation of the replication senescence mechanism. Our analysis of genetic studies shows that progressive chromosome heterochromatinization (condensation of eu- and heterochromatin regions) occurs in aging. Decreases in the repair processes and increases in the frequency of chromosome aberrations during aging are secondary to this progressive chromosome heterochromatinization. Chromosome heterochromatinization is a key factor in aging but may be reversible under the influence of bioregulators, some chemical substances, and heavy metal salts. The study of chromosome heterochromatinization may provide clues to the potential for prolonging the human lifespan.  相似文献   
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