Intragenic polymorphisms of factor VIII and IX genes and their utility in the indirect diagnosis of carriers of Haemophilias A and B

Haemophilia A and B are considered sex-linked inherited diseases caused by mutations in genes that encode factors VIII and IX, respectively. This results in the deficiency of these proteins plasma levels which are actively involved in the mechanism of blood coagulation. It has been reported that several mutations are responsible for the alteration of these genes, which is why the application of a molecular diagnostic method for the direct identification of female carriers is impractical. An appropriate diagnostic strategy is the indirect analysis of polymorphisms linked to the gene. The aim of this study was to identify female carriers in different families with history of HA and HB that live in Zulia State, Venezuela, characterizing intragenic gene polymorphisms of the clotting factors VIII and IX, which helped to identify and assign haplotypes, to diagnose or to exclude the carrying condition, to 95% of women who were needing the study for HA and to 100% for HB.     

Generation of reactive oxygen species by Candida albicans in relation to morphogenesis

Candida albicans is able to generate significant amounts of reactive oxygen species (ROS). In this study, ROS generation by yeast and hyphal forms of the strain 3153 A was analyzed to determine whether ROS generation could be a major factor in the invasive behavior of germinative cells. Furthermore, the virulent strain CA6 and its avirulent and agerminative mutant VIR3 were compared. ROS were measured by lucigenin-enhanced chemiluminescence and a cytochrome c assay. During the blastoconidial phase of all strains moderate amounts of ROS were found at cell concentrations > 1 x 10(5)/ml. However, ROS generation appeared to be specifically inhibited at cell concentrations > 1 x 10(8)/ml, and this was found in both assays. As shown in comparative experiments, the medium used for measurement markedly affected the total amount of ROS. Hyphae of strain 3153 A generated a significantly higher amount of ROS than yeast cells and cells with germ tubes (P < 0.001). The strain CA6 showed significantly higher ROS generation than the VIR3 strain for both blastoconidiae and after 30 min of induction of hypha formation (P < 0.05). In conclusion, hypha formation, usually acknowledged as a major factor in Candida pathogenicity, was associated with markedly increased ROS formation. ROS generation was not closely linked to the ability to form hyphae, but was highest in germinative cells.     

Integration of new safety technologies for needle aspiration of breast cysts

Introduction  National and international regulatory agencies and professional societies mandate systematic improvements in both the safety of patients and heath care workers (HCW), including the integration of safety technologies into the procedures of obstetrics and gynecology (Ob-Gyn). Materials and Methods   Using national resources for patient safety and literature review, these safety technologies were identified: (1) a safety needle to reduce needle sticks to HCW, and (2) the reciprocating procedure device (RPD) to reduce injuries to patients. These technologies were introduced in a trial fashion into routine breast cyst aspiration, and physician responses were determined. Results   The safety needle presented a number of difficulties associated with the safety sheath, but could be used efficiently for breast cyst aspiration. The RPD safety device functioned well for breast aspiration procedures and was well accepted by physicians. Conclusions   New safety technologies can be successfully evaluated and introduced into the clinic to improve patient and HCW safety during outpatient breast procedures. Since these technologies have been demonstrated to decrease injuries to patients and HCW by 60–70%, serious efforts should be undertaken to systematically integrate safety technologies into the routine practice, including aspiration of breast cysts.     

Cystine dimethylester model of cystinosis: still reliable?

The ability of cystine dimethylester (CDME) to load lysosomes with cystine has been used to establish the basic defect in cystinosis: defective cystine exodus from lysosomes. Using CDME loading, it has been postulated that cystine accumulation in cystinosis affects mitochondrial ATP production, resulting in defective renal tubular reabsorption. Recent studies in cystinotic fibroblasts, however, show normal adenosine triphosphate (ATP) generation capacity. To investigate the effect of CDME in more detail, mitochondrial ATP generation, reactive oxygen species production, and viability are compared in fibroblasts loaded with CDME with those of cystinotic cells with a defective cystine transporter. Intracellular cystine levels were comparable in fibroblasts loaded with CDME (1 mM, 30 min) and cystinotic fibroblasts. Intracellular ATP levels and mitochondrial ATP production were decreased in fibroblasts loaded with CDME, but normal in cystinotic fibroblasts. Superoxide production was increased with 300% after CDME loading, whereas no changes were observed in cystinotic fibroblasts. Exposure to CDME led to cell death in a time- and concentration-dependent manner. Our data demonstrate that CDME has a toxic effect on mitochondrial ATP production and cell viability. These effects are not observed in cystinotic cells, indicating that a more appropriate model is required for studying the pathogenesis of cystinosis.