Systemic fatty acid responses to transient focal cerebral ischemia: influence of neuroprotectant therapy with human albumin

Human albumin therapy is highly neuroprotective in focal cerebral ischemia. Because albumin is the main carrier of free fatty acids (FFA) in plasma, we investigated the content and composition of plasma FFA in jugular vein (JV), femoral artery (FA) and femoral vein (FV) of rats given intravenous human albumin (1.25 g/kg) or saline vehicle (5 mL/kg) 1 h after a 2 h middle cerebral artery occlusion (MCAo) or sham surgery. Arachidonic acid was the only FFA significantly increased by MCAo in all plasma samples prior to albumin administration, remaining at the same level regardless of subsequent treatments. Albumin treatment induced in both MCAo- and sham-groups a 1.7-fold increase in total plasma FFA (mainly 16:0, 18:1, 18:2n-6) during 90-min reperfusion. MCAo selectively stimulated the albumin-mediated mobilization of n-3 polyunsaturated fatty acids (PUFA), with an early increase in 22:5n-3 and 22:6n-3 in the FA prior to detectable changes in the JV. In the MCAo-albumin group, the lower level of FFA in JV as compared with FA and FV suggests an albumin-mediated systemic mobilization and supply of FFA to the brain, which may favor the replenishment of PUFA lost from cellular membranes during ischemia and/or to serve as an alternative source of energy, thus contributing to albumin neuroprotection.     

Estimating temperature‐dependent developmental rates of potato tuberworm,Phthorimaea operculella (Lepidoptera: Gelechiidae)

Abstract The potato tuberworm, Phthorimaea operculella (Zeller) (Lepidoptera: Gelechiidae), is the most destructive pest of potato, Solanum tuberosum L. (Solanaceae), in tropical and subtropical regions in both field and storeroom situations. The modeling of temperature‐dependent development can be useful in forecasting occurrence and population dynamics of the pests. Published developmental parameters for this pest vary greatly for many reasons. We determined temperature‐dependent development of P. operculella at seven constant temperatures (16, 20, 24, 28, 32, 34 and 36 °C). Developmental period of whole immature stage (egg to the end of the pupal stage) varied from 75.5 days at 16 °C to 17 days at 32 °C. The population failed to survive at 36 °C. The observed data was modeled to determine mathematical functions for simulating P. operculella development in each stage of development and overall. Two linear models, ordinary linear regression and the Ikemoto linear model were used to describe the relationship between temperature and development rate of the different stages of P. operculella and estimating the thermal constant and lower temperature threshold. The lower temperature threshold (t) and thermal constant (k) of whole immature stage were estimated to be 11.6 °C and 338.5 DD by Ikemoto linear model, and the estimated parameters were not substantially different with those estimated by ordinary linear models. Different models provided a better fit to the various developmental stages. Of the eleven nonlinear models fitted, the Beriere‐1, Logan‐6 and Lactin‐1 model was found to be the best for modeling development rate of egg, larva and pupa of P. operculella, respectively. Phenological models based on these findings can be part of a decision‐support tool to improve the efficiency of pest management programs.     

Differences between adrenal adenoma causing primary aldosteronism and other adrenal tissues in the incorporation of labeled steroid precursors into their products

The incorporation and conversion of several labeled steroid precursors into their products were examined in slices of adrenal tissue from two patients with primary aldosteronism and compared with that in “normal” adrenal tissue and adrenal tissues from a patient with Gushing's syndrome. The products of the incorporation were separated by Sephadex LH-20 column chromatography. The major products of conversion in the adenomatous tissue of primary aldosteronism were 18-hydroxycorticosterone and lesser amounts of aldosterone. Smaller amounts of 18-hydroxycorticosterone were isolated from all other adrenal tissues studied. No aldosterone could be recovered after incubating any of the adrenal tissue studied with labeled 18-hydroxy-11-deoxycorticosterone or 18-hydroxycorticosterone as precursor steroid. These $\text{in vitro}$ results seem to suggest that there is increased 18-hydroxylation in the adenoma of primary aldosteronism compared with other tissues and that relatively more 18-hydroxycorticosterone is produced in such tissue than aldosterone.     

Differential expression of extracellular matrix components in the Fallopian tubes throughout the menstrual cycle

ABSTRACT: BACKGROUND: One of the unique characteristics of the female genital tract is the extensive tissue remodeling observed throughout the menstrual cycle. Multiple components of the extracellular matrix take part in this tissue rebuilding; however, the individual components involved have not been identified. METHODS: In the present study, the expression of extracellular matrix proteins and selected matrix metalloproteinase (MMP) activities in Fallopian tubes (FT) throughout the menstrual cycle were examined by PCR array, immunocytochemistry, zymography and bioinformatics. RESULTS: Of the eighty-four genes analyzed, eighty-three were expressed in the FT during at least one stage of the menstrual cycle. We observed a significant increase (>/=2-fold) in ADAMTS1, ADAMTS13, COL7A1, MMP3, MMP9, PECAM1, and THBS3 in the periovulatory phase compared to the follicular phase. Meanwhile, we observed a significant decrease (>/= 2-fold) in COL7A1, ICAM1, ITGA8, MMP16, MMP9, CLEC3B, SELE and TIMP2 in the lutheal phase compared to the periovulatory phase. Immunocytochemistry showed that MMP-3 and MMP-9 were localized in the endosalpinx during all phases of the menstrual cycle. Gelatin zymograms detected non-cycle-dependent protease activity. CONCLUSIONS: Several extracellular matrix components were regulated throughout the menstrual cycle in a cyclic pattern, suggesting a possible steroid regulation and a role in tissue remodeling and FT functions.     

Risks and Population Burden of Cardiovascular Diseases Associated with Diabetes in China: A Prospective Study of 0.5 Million Adults

BackgroundIn China, diabetes prevalence is rising rapidly, but little is known about the associated risks and population burden of cardiovascular diseases. We assess associations of diabetes with major cardiovascular diseases and the relevance of diabetes duration and other modifiable risk factors to these associations.ConclusionsAmong Chinese adults, diabetes is associated with significantly increased risks of major cardiovascular diseases. The increasing prevalence and younger age of onset of diabetes foreshadow greater diabetes-attributable disease burden in China.     

Depletion of the 110-kilodalton isoform of poly(ADP-ribose) glycohydrolase increases sensitivity to genotoxic and endotoxic stress in mice

Poly(ADP-ribosylation) is rapidly stimulated in cells following DNA damage. This posttranslational modification is regulated by the synthesizing enzyme poly(ADP-ribose) polymerase 1 (PARP-1) and the degrading enzyme poly(ADP-ribose) glycohydrolase (PARG). Although the role of PARP-1 in response to DNA damage has been studied extensively, the function of PARG and the impact of poly(ADP-ribose) homeostasis in various cellular processes are largely unknown. Here we show that by gene targeting in embryonic stem cells and mice, we specifically deleted the 110-kDa PARG protein (PARG(110)) normally found in the nucleus and that depletion of PARG(110) severely compromised the automodification of PARP-1 in vivo. PARG(110)-deficient mice were viable and fertile, but these mice were hypersensitive to alkylating agents and ionizing radiation. In addition, these mice were susceptible to streptozotocin-induced diabetes and endotoxic shock. These data indicate that PARG(110) plays an important role in DNA damage responses and in pathological processes.     

Hydrogen Sulfide-Producing Variants of Escherichia coli

Seventeen strains of H(2)S-producing variants of Escherichia coli were isolated from specimens submitted for microbiological study (ten from stool, five from urine, and two from postmortem material). Production of H(2)S was unstable in several strains; however, other than their production of H(2)S, all strains closely resembled typical E. coli in their biochemical reactions. In vitro susceptibilities of the H(2)S-producing variants to antimicrobics closely resembled those of typical E. coli in this laboratory.     

Vangl2/RhoA Signaling Pathway Regulates Stem Cell Self-Renewal Programs and Growth in Rhabdomyosarcoma

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Variations in mass transfer to single endothelial cells

Mass transfer between flowing blood and arterial mural cells (including vascular endothelial cells) may play an important role in atherogenesis. Endothelial cells are known to have an apical surface topography that is not flat, and hence mass transfer patterns to individual endothelial cells are likely affected by the local cellular topography. The purpose of this paper is to investigate the relationship between vascular endothelial cell surface topography and cellular level mass transfer. Confluent porcine endothelial monolayers were cultured under both shear and static conditions and atomic force microscopy was used to measure endothelial cell topography. Using finite element methods and the measured cell topography, flow and concentration fields were calculated for a typical, small, blood-borne solute. A relative Sherwood number was defined as the difference between the computed Sherwood number and that predicted by the Leveque solution for mass transfer over a flat surface: this eliminates the effects of axial location on mass transfer efficiency. The average intracellular relative Sherwood number range was found to be dependent on cell height and not dependent on cell elongation due to shear stress in culture. The mass flux to individual cells reached a maximum at the highest point on the endothelial cell surface, typically corresponding to the nucleus of the cell. Therefore, for small receptor-mediated solutes, increased solute uptake efficiency can be achieved by concentrating receptors near the nucleus. The main conclusion of the work is that although the rate of mass transfer varies greatly over an individual cell, the average mass transfer rate to a cell is close to that predicted for a flat cell. In comparison to other hemodynamic factors, the topography of endothelial cells therefore seems to have little effect on mass transfer rates and is likely physiologically insignificant.