Pentosidine plasma levels and relation with metabolic control in diabetic patients.

Levels of plasma pentosidine, a well-known AGE, were measured in type 2 diabetic patients in varying states of metabolic control to verify possible relationships between this parameter and traditional metabolic control parameters such as HbA1c and plasma glucose levels. At baseline, mean values of fasting plasma glucose, HbA1c and pentosidine were significantly higher in diabetic patients than those of controls, confirming patients' poor glycemic control. After ten months, patients with good metabolic control achieved showed near-normal HbA1c levels and reduced but not normalized pentosidine levels. Significant differences were found in the mean percentage decrease in the parameters. Regarding linear correlation, HbA1c levels only showed a positive relationship with plasma glucose values at baseline. Patients affected by chronic complications showed higher levels of pentosidine than those without complications. Thus, pentosidine plasma levels may be used to evaluate very long-term metabolic control in diabetic patients. In addition, a period of ten months of acceptable metabolic control is not enough to normalize pentosidine levels in diabetics, thus emphasizing the need for a longer period of improved metabolic control to reduce both this parameter and the burden of chronic diabetic complications.     

Desaturase activities and metabolic control in type 2 diabetes

The aim of this study was to elucidate the effects of a poor glycemic control on fatty acid composition and desaturase activities in type 2 diabetic patients. Plasma phospholipid fatty acid composition and desaturase activities (estimated from fatty acid product to precursor ratios) were measured in 30 type 2 diabetic patients during poor metabolic control and after achieving a good metabolic control. Significant changes were recorded in the percentages of palmitic, stearic, dihomo-gamma-linolenic, docosatetraenoic and docosapentaenoic acid. The delta-5 desaturase activity was significantly higher with poor than with good metabolic control. The changes identified in plasma phospholipid fatty acid composition and the desaturase activity in type 2 diabetic patients go in the opposite direction to those described in similar conditions in type 1 diabetic patients and may be relevant to a better understanding of the role of metabolic control in the progression of chronic complications in type 2 diabetic patients.     

Niche-independent symmetrical self-renewal of a mammalian tissue stem cell

Pluripotent mouse embryonic stem (ES) cells multiply in simple monoculture by symmetrical divisions. In vivo, however, stem cells are generally thought to depend on specialised cellular microenvironments and to undergo predominantly asymmetric divisions. Ex vivo expansion of pure populations of tissue stem cells has proven elusive. Neural progenitor cells are propagated in combination with differentiating progeny in floating clusters called neurospheres. The proportion of stem cells in neurospheres is low, however, and they cannot be directly observed or interrogated. Here we demonstrate that the complex neurosphere environment is dispensable for stem cell maintenance, and that the combination of fibroblast growth factor 2 (FGF-2) and epidermal growth factor (EGF) is sufficient for derivation and continuous expansion by symmetrical division of pure cultures of neural stem (NS) cells. NS cells were derived first from mouse ES cells. Neural lineage induction was followed by growth factor addition in basal culture media. In the presence of only EGF and FGF-2, resulting NS cells proliferate continuously, are diploid, and clonogenic. After prolonged expansion, they remain able to differentiate efficiently into neurons and astrocytes in vitro and upon transplantation into the adult brain. Colonies generated from single NS cells all produce neurons upon growth factor withdrawal. NS cells uniformly express morphological, cell biological, and molecular features of radial glia, developmental precursors of neurons and glia. Consistent with this profile, adherent NS cell lines can readily be established from foetal mouse brain. Similar NS cells can be generated from human ES cells and human foetal brain. The extrinsic factors EGF plus FGF-2 are sufficient to sustain pure symmetrical self-renewing divisions of NS cells. The resultant cultures constitute the first known example of tissue-specific stem cells that can be propagated without accompanying differentiation. These homogenous cultures will enable delineation of molecular mechanisms that define a tissue-specific stem cell and allow direct comparison with pluripotent ES cells.     

Late Carnian (Tuvalian,Tropites dilleri zone) ostracods (Crustacea) from the Mufara Formation (Monte Scalpello,Central-Eastern Sicily,Italy)

Ostracod association from the Upper Triassic (Tropites dilleri zone of the Carnian stage) of the sedimentary succession (Mufara Formation) exposed along the east side of Monte Scalpello (Catenanuova, central eastern Sicily) has been studied for the first time. The specimens, silicified, are rare but well preserved and often consist of complete carapaces. They belong to eight families: Healdiidae, Cavellinidae, Bairdiidae, Acratiidae, Bythocyprididae, Pontocyprididae, Judahellidae, Glorianellidae. Twenty-three taxa have been listed; the family Bairdiidae is the most represented among all the others with fifteen species. Four species are new: Bairdia scaliae n. sp., Acratia maugerii n. sp., “Anchistrocheles” gemmellaroi n. sp. and Judahella? montanarii n. sp. Other species are left in open nomenclature because of the lack of specimens.     

In vitro metabolism of vitamin D3 by isolated liver cells

Summary Liver cells were prepared from rats fed a rachitogenic diet to investigate the hepatic metabolism of [ — 1,2 —³H₂] vitamin D₃. Rat hepatocytes suspended in Hanks medium rapidly took up labeled vitamin D₃ from the incubation medium and converted this sterol to various metabolites, including 25-hydroxy vitamin D₃ (25-OH-D₃). There was a steady increment in the cellular production of 25-OH-D₃ and of the more polar metabolites of vitamin D₃ over 3 hr of incubation as determined by thin layer chromatography. Neither the addition of cyclic nucleotides or dexamethasone to, nor the removal of calcium or phosphate from the medium resulted in changes in the rate of conversion of vitamin D₃ to its products. Rats pretreated with sodium diphenylhydantoin converted labeled vitamin D₃ to its metabolites at the same rate as control rats. These data indicate that isolated liver cells retain the capacity for vitamin D₃ hydroxylation, but suggest that the rate of this process does not undergo rapid changes in response to metabolic stimulation.Recipient of Research Career Development Award 1 K04 HL-00089.     

Effect of Moringa oleifera leaves on hematological profile of fluorosis affected rats

Fluorosis is a metabolic disease that is endemic in nearly 25 countries with India being one of the most affected. It primarily affects the bone and the teeth. Moringa oleifera (MO) leaves are known to reduce the effect of fluorosis on various tissues. Therefore, it is of interest to document the effect of Moringa oleifera leaves on the hematological profile of fluorosis affected rats. Twenty four Sprague Dawley rats were housed two per cage in a room with 12 hours light and 12 hours dark cycle. The rats were allowed to adjust to the laboratory environment for about one to two weeks before the beginning of the study. This study reveals that MO leaves is effective in reducing the plasma fluoride content. It also helps in improving the Hb % and RBC count in fluorosis affected rats. Data shows that Moringa olifera leaves powder is effective in reducing the plasma fluoride content. It also helps in improving the Hemoglobin percentage & Red Blood Cell count in fluorosis affected rats.     

Innate immune dysfunction in HIV infection: effect of HIV envelope-NK cell interactions

We have previously described a number of NK cell dysfunctions in HIV-viremic individuals. In the present study, we performed DNA microarray analysis followed by phenotypic and functional characterization in an effort to investigate which HIV envelope glycoproteins (gp120) affect the physiologic functions of NK cells. Upon treatment of NK cells with HIV gp120, DNA microarray analyses indicated up-regulation of several categories of genes that are associated with apoptosis, suppression of both cellular proliferation and survival, as well as down-regulation of genes that play a vital role in cell proliferation, innate immune defense mechanism, and cell survival. Both subtypes of gp120 suppressed NK cell cytotoxicity, proliferation, and the ability to secrete IFN-gamma. NK cells exposed to X4-subtype HIV gp120 showed a significant decrease in the levels of CC chemokines, while exposure to R5-subtype HIV gp120 had minimal effect. Extended exposure to HIV gp120 resulted in apoptosis of NK cells, further validating the microarray data. Our data demonstrate that exposure of NK cells to HIV envelope proteins results in profound cellular abnormalities at the level of gene expression as well as generic cell functions. These findings are likely to be a consequence of a direct HIV gp120-mediated effect on NK cells. Identification of specific surface receptors on NK cells that interact with HIV envelope proteins might explain how HIV is capable of circumventing innate immune defense mechanisms and establishing infection in susceptible individuals.     

Enhancement in leghemoglobin content of root nodules by exclusion of solar UV-A and UV-B radiation in soybean

The impact of exclusion of solar UV-B (280–320 nm) and UV-A+B (280–400 nm) radiation on the root nodules was studied in soybean(Glycine max var. MACS 330). Soybean plants were grown in the tropical region of Indore (Latitude-22.4°N), India under field conditions in metal cages covered with polyester exclusion filters that specifically cut off UV-B (<320 nm) and UV-A+B (<400 nm) radiation; control plants were grown under ambient solar radiation. Leghemoglobin content was analyzed in the root nodules on the 50^th day after emergence of seedlings. Exclusion of UV radiations significantly enhanced the leghemoglobin content in the nodules on fresh weight basis; 25% and 45% higher amount of leghemoglobin were present in the nodules after the exclusion of UV-B and UV-A+B radiation respectively. Analysis by native and SDS-PAGE showed high intense bands of leghemoglobin after the exclusion of UV-A+B as compared to control. Exclusion of UV radiation also enhanced the growth of roots as well as aerial parts of the plants. UV Exclusion increased nodulation by increase in the number and size of nodules. The results are discussed in the light of advantage of exclusion for enhancing protein/nitrogen content in the plants.