Urinary Excretion of Zinc and Metabolic Control of Patients with Diabetes Type 2

The objective of this study was to assess urinary excretion of zinc and evaluation parameters of metabolic control in type 2 diabetic patients. Thirty-one type 2 diabetic patients, of both genders, with 5.8 ± 5.6 years average time of the disease, age range 20–60 years, were selected. Evaluation of the nutritional status was performed using anthropometric measurements. To evaluate food consumption, the 3-day alimentary log method was used, and its analysis was performed using a software. Determination of urinary zinc was by atomic absorption spectrophotometry. From the obtained results, it was concluded that 51.6% of the patients were overweight. The mean of found waist circumference was 100.4 and 92.2 cm for men and women, respectively. Blood glucose and glycated hemoglobin values were higher than reference values, and plasma albumin concentration was adequate. The median of found urinary zinc excretion was 474.9 μg/24 h, within normal standards (300–600 μg/day). Regarding diet composition, calorie and protein concentration were above recommendation, while mean zinc concentration was adequate. This data allow the conclusion that the evaluated patients presented adequate urinary zinc excretion in comparison with reference values.     

The vicious cycle of apoptotic beta-cell death in type 1 diabetes

Autoimmune insulitis, the cause of type 1 diabetes, evolves through several discrete stages that culminate in beta-cell death. In the first stage, antigenic epitopes of B-cell-specific peptides are processed by antigen presenting cells in local lymph nodes, and auto-reactive lymphocyte clones are propagated. Subsequently, cell-mediated and direct cytokine-mediated reactions are generated against the beta-cells, and the beta-cells are sensitized to apoptosis. Ironically, the beta-cells themselves contribute some of the cytokines and chemokines that provoke the immune reaction within the islets. Once this vicious cycle of autoimmunity is fully developed, the fate of the beta-cells in the islets is sealed, and clinical diabetes inevitably ensues. Differences in various aspects of these concurrent events appear to underlie the significant discrepancies in experimental data observed in experimental models that simulate autoimmune insulitis.     

Brain metastases as primary manifestation of a melanocytic malignant peripheral nerve sheath tumor in a 60-year-old man

Background  

Malignant peripheral nerve sheath tumors are rare tumor entities that originate from peripheral nerve sheaths and have an unfavorable prognosis. Metastatic spread to the cerebral parenchyma is absolutely rare. This case report describes the clinical course in a 60-year-old man whose tumor came to medical attention because of a seizure.     

Solvent-free synthesis of chiral Schiff-base ligands based on ferrocene under microwave irradiation and application to enantioselective nitroaldol (Henry) reaction

Chiral Schiff-bases 3a-f based on ferrocene were designed and synthesized using solvent-free methods by mixing ferrocene carbaldehyde 1 with amino alcohols and amines 2a-f under microwave irradiation and classical method for the enantioselective nitroaldol (Henry) reaction. The Schiff-bases were obtained in shorter reaction times and improved yield under microwave irradiation method over classical method. The highest enantioselectivity was observed in ligand 3e (95% ee) when CH(2)Cl(2) was used as solvent.     

Influence of membrane fouling reducers (MFRs) on filterability of disperse mixed liquor of jet loop bioreactors

The effects of membrane fouling reducers (MFRs) (the cationic polyelectrolyte (CPE) and FeCI₃) on membrane fouling were studied in a lab-scale jet loop submerged membrane bioreactor (JL-SMBR) system. The optimum dosages of MFRs (CPE dosage = 20 mg g⁻¹MLSS, FeCI₃ dosage = 14 mg g⁻¹MLSS) were continuously fed to JL-SMBR system. The soluble and bound EPS concentrations as well as MLSS concentration in the mixed liquor of JL-SMBR were not changed substantially by the addition of MFRs. However, significant differences were observed in particle size and relative hydrophobicity. Filtration tests were performed by using different membrane types (polycarbonate (PC) and nitrocellulose mixed ester (ME)) and various pore sizes (0.45-0.22-0.1 μm). The steady state fluxes (J_ss) of membranes increased at all membranes after MFRs addition to JL-SMBR. The filtration results showed that MFRs addition was an effective approach in terms of improvement in filtration performance for both membrane types.     

Ancient and recent evolutionary history of the bruchid beetle, Acanthoscelides obtectus Say, a cosmopolitan pest of beans

Acanthoscelides obtectus Say is a bruchid species of Neotropical origin, and is specialized on beans of the Phaseolus vulgaris L. group. Since the domestication and diffusion of beans, A. obtectus has become cosmopolitan through human-mediated migrations and is now a major pest in bean granaries. Using phylogeographic methods applied to mitochondrial DNA (mtDNA) and nuclear microsatellite molecular markers, we show that the origin of this species is probably further south than Mesoamerica, as commonly thought. Our results also indicate that A. obtectus and its Mesoamerican sister species Acanthoscelides obvelatus, two morphologically close species differing principally in voltinism, speciated in allopatry: A. obtectus (multivoltine) arising in Andean America and A. obvelatus (univoltine) in Mesoamerica. In contrast to Mesoamerica where beans fruit once yearly, wild beans in Andean America fruit year-round, especially in regions showing little or no seasonality. In such habitats where resources are continuously present, multivoltinism is adaptive. According to existing hypotheses, multivoltinism in A. obtectus is a new adaptation that evolved after bean domestication. Our data suggest the alternative hypothesis that multivoltinism is an older trait, adapted to exploit the year-round fruiting of wild beans in relatively aseasonal habitats, and allowed A. obtectus to become a pest in bean granaries. This trait also permitted this species to disperse through human-mediated migrations associated with diffusion of domesticated beans. We also show that diversity of Old World A. obtectus populations can be quite well explained by a single colonization event about 500 bp. Human-mediated migrations appear not to be rare, as our results indicate a second more recent migration event from Andean America to Mexico.     

Leukomogenic factors downregulate heparanase expression in acute myeloid leukemia cells

Heparanase is a heparan sulfate-degrading endoglycosidase expressed by mature monocytes and myeloid cells, but not by immature hematopoietic progenitors. Heparanase gene expression is upregulated during differentiation of immature myeloid cells. PML-RARalpha and PLZF-RARalpha fusion gene products associated with acute promyelocytic leukemia abrogate myeloid differentiation and heparanase expression. AML-Eto, a translocation product associated with AML FAB M2, also downregulates heparanase gene expression. The common mechanism that underlines the activity of these three fusion gene products involves the recruitment of histone deacetylase complexes to specific locations within the DNA. We found that retinoic acid that dissociates PML-RARalpha from the DNA, and which is used to treat acute promyelocytic leukemia patients, restores heparanase expression to normal levels in an acute promyelocytic leukemia cell line. The retinoic acid effects were also observed in primary acute promyelocytic leukemia cells and in a retinoic acid-treated acute promyelocytic leukemia patient. Histone deacetylase inhibitor reverses the downregulation of heparanase expression induced by the AML-Eto fusion gene product in M2 type AML. In summary, we have characterized a link between leukomogenic factors and the downregulation of heparanase in myeloid leukemic cells.     

Our perception of developmental plasticity: esse est percipi (to be is to be perceived)?

The continuing interest in the biology of stem cells is enhanced by new discoveries surrounding developmental plasticity of both embryonic and adult stem cells. Adoptive transfer of concepts and definitions from the hematopoietic system to other tissue stem cells suggests inclusion of characteristics such as ability to self-renew and differentiate to functionally reconstitute a tissue/organ of origin. How adequate and accurate are these definitions? Within the great unknown of how these cells function, modulate their gene expression patterns and respond to extrinsic signals, it is apparent that there are numerous levels of stemness. We may envision a scale of developmental flexibility. At one end of the scale are positioned the embryonic stem cells, and at the other end are positioned partially-differentiated, differentiation restricted (committed) tissue/organ stem cells. There is evidence that some stem cells in the adult are pluripotent, thus positioned close to the embryonic end of the stem scale. It is uncertain yet to what extent stem cells can move back and forth along the stem scale.