Haplotype analysis of the Mexican frameshift Cd 11 (−T) and −28 A→C β-thalassemia alleles

The origins of the −28 A→C and frameshift Cd 11 −T (Fs Cd 11 −T) alleles were investigated by β-globin cluster haplotype analysis. These alleles were found in a Mexican mestizo family with β-thalassemia (β-thal). The -28 A→C mutation was described previously in Kurdish Jews linked to the most common haplotype in the world (+−−−−++), the same haplotype observed in this Mexican family. Therefore, it is not possible to assess a new origin of the −28 A→C mutation in our population. The Fs Cd 11 −T allele, not reported to date in any other populations, was linked to the −++−−+− haplotype (sixth in frequency in the world). This haplotype has not been reported in association with any β-thal mutant, suggesting a Mexican origin for the Cd 11 −T mutation. © 1995 Wiley-Liss, Inc.     

Growth factor responsiveness of human articular chondrocytes in aging and development

Objective. To examine growth factor responses of human articular chondrocytes in aging and development. We have previously established a growth factor response profile for adult human articular chondrocytes and shown that transforming growth factor β (TGFβ) is the most potent mitogen among a variety of factors tested. Methods. Chondrocytes were isolated from human articular cartilage obtained from donors ages 11–83 years and tested in primary culture for proliferative responses to serum and recombinant preparations of the major chondrocyte growth factors. Proliferation was measured by ³H-thymidine incorporation and cell counting. Skeletal maturity of the young donors was determined by radiographic assessment of Risser's index. Results. Chondrocytes showed a continuous age-related decline in the proliferative response to serum. Analysis of recombinant growth factors showed that with increasing donor age, there was a decrease in the levels of DNA synthesis in response to all factors tested. In chondrocytes from adult donors, there was no change in the relative potencies of the different growth factors. The decrease in the levels of DNA synthesis as measured by ³H-thymidine incorporation corresponded to a reduced rate of in vitro cell replication with increasing donor age. In addition to the quantitative changes in the proliferative responses of chondrocytes with increasing age, there was a qualitative change in the pattern of growth factor responses during development. Cells from young donors (ages 10–20) responded better to platelet-derived growth factor, AA chain homodimer (PDGF-AA) than to TGFβ1, while the inverse pattern was seen in cells from adult donors. This decrease in the response to PDGF-AA was significantly correlated with increasing skeletal maturity. Conclusion. Chondrocyte growth factor responsiveness shows qualitative changes during development, and after skeletal maturity, there is a profound decline in the levels of DNA synthesis and cell replication in response to the known chondrocyte growth factors.     

The multi-attitude suicide tendency scale: Psychometric characteristics in an american sample

The Multi-Attitude Suicide Tendency Scale (MAST) was designed to assess suicidal tendencies in youth. This 30-item scale has four types of attitudes: attraction to life, repulsion by life, attraction to death, and repulsion by death. Normative, factor structure, and psychometric data were investigated with American youth with a range of suicidal ideations and behaviors. The reported factor structure was replicated with American youths. In addition, all four factor scales showed good reliability estimates. Finally, the relationships among the MAST factors and measures of suicidal behavior and ideation, social desirability, and general psychopathology were examined.     

Synergistic Effect of Squalene and Hydroxytyrosol on Highly Invasive MDA-MB-231 Breast Cancer Cells

Several studies relate Mediterranean diet and virgin olive oil (VOO) intake with lower risk of several chronic diseases, including breast cancer. Many of them described antitumor properties of isolated minor compounds present in VOO, but beneficial properties of VOO arise from the effects of all its compounds acting together. The aim of the present study was to test the antitumor effects of two minor compounds from VOO (hydroxytyrosol (HT) and squalene (SQ)) on highly metastatic human breast tumor cells (MDA-MB-231) when acting in combination. Both isolated compounds were previously analyzed without showing any antitumoral effect on highly invasive MDA-MB-231 breast cancer cells, but the present results show that HT at 100 µM, combined with different concentrations of SQ, could exert antitumor effects. When they are combined, HT and SQ are able to inhibit cell proliferation, promoting apoptosis and DNA damage in metastatic breast cancer cells. Therefore, our results suggest that the health-promoting properties of VOO may be due, at least in part, to the combined action of these two minor compounds.     

Effect of the Processing Parameters on the Porosity and Mechanical Behavior of Titanium Samples with Bimodal Microstructure Produced via Hot Pressing

Commercially pure (c.p.) titanium grade IV with a bimodal microstructure is a promising material for biomedical implants. The influence of the processing parameters on the physical, microstructural, and mechanical properties was investigated. The bimodal microstructure was achieved from the blends of powder particles with different sizes, while the porous structure was obtained using the space-holder technique (50 vol.% of ammonium bicarbonate). Mechanically milled powders (10 and 20 h) were mixed in 50 wt.% or 75 wt.% with c.p. titanium. Four different mixtures of powders were precompacted via uniaxial cold pressing at 400 MPa. Then, the specimens were sintered at 750 °C via hot pressing in an argon gas atmosphere. The presence of a bimodal microstructure, comprised of small-grain regions separated by coarse-grain ones, was confirmed by optical and scanning electron microscopies. The samples with a bimodal microstructure exhibited an increase in the porosity compared with the commercially available pure Ti. In addition, the hardness was increased while the Young’s modulus was decreased in the specimens with 75 wt.% of the milled powders (20 h).     

Risk Factors for Development of Rectal Neuroendocrine Tumors Longer Than 9 mm: Retrospective Cohort

BackgroundRectal neuroendocrine tumors (R-NET) represent the most frequent of gastroenteropancreatic neuroendocrine neoplasms (NEN-GEP) according to the United States Surveillance, Epidemiology, and End Results database. With an annual percentage of occurrence increasing to 8.2% of all rectal neoplasms, R-NET affect less than 2% and are reported in only 0.05% to 0.07% of patients undergoing colorectal cancer (CRC) screening. The primary objective of this study was to assess the risk factors associated with R-NET greater than 10 mm. As a secondary objective, it was also aimed to evaluate the response to endoscopic treatment.Methods: This was a retrospective study, using data collected through the analysis of medical records of colonoscopies performed from January 2008 to December 2014. Records of polypectomies were identified, and the results were searched for pathological findings of R-NET. We also gathered epidemiological data and outcomes as risk factors for lesions greater than or equal to 10 mm, with local and distant recurrence.Results: During the study period, 18 218 colonoscopies were performed and 10 865 polypoid lesions were detected and removed, 20 with R-NET anatomopathology. The detection rate was 0.1%. The risk factors associated with major lesions were Japanese ethnicity, the lack of previous cancer diagnosis, and a Ki67 index > 2%. The mean follow-up was 56.6 months, and there was no local lymph node recurrence or distant relapse.ConclusionThis study concludes that endoscopic resection is a good and effective method for treatment of Grade 1 rectal NET smaller than 11 mm, with high cure rates and low rates of local or distant relapse.