bluuebunny/crossref_metadata_2025_split huggingface dataset:
Obesity, Insulin Resistance, and Microvessel Density
Authors: Frisbee Jefferson C. 
Published: July 2007

ABSTRACTThe growing incidence and prevalence of the overweight/obese condition across developed economies worldwide has an enormous impact on increasing the risk for the development of impaired glycemic control or insulin resistance and ultimately peripheral vascular disease (PVD) in afflicted individuals. This places an enormous economic and social burden on these societies, in terms of additional health care costs and lost productivity and through a reduction in the quality of life of the individual owing, in part, to the progressive PVD. Characterized by an inability of the vascular systems to adequately perfuse tissues and organs relative to their metabolic demand, PVD is in part a function of a structural remodeling of the microvascular networks such that the density of microvessel and capillaries within tissues is reduced below that under normal conditions, with the potential for profound negative impacts on the processes of mass transport and exchange. The review discusses the severity of the obesity “epidemic” from the perspective of PVD and the effects of the development of the obese, insulin‐resistant condition on tissue/organ microvessel density. Additional material is reviewed that addresses ameliorative treatments, primarily exercise training, on blunting microvessel loss in the obese, insulin‐resistant individual, and on potential mechanistic contributors that warrant considerable future investigation.
Obesity, Insulin Resistance, and Renal Function
Authors: Knight Sarah F. , Imig John D. 
Published: July 2007

ABSTRACTThere is a growing body of evidence indicating that obesity and insulin resistance contribute to the progression of renal disease. A low‐grade inflammatory response occurs in obesity and insulin resistance that causes an increase in macrophage infiltration into the adipose tissue and the kidney. The infiltration of macrophages gives rise to the production of an array of pro‐inflammatory cytokines and downstream elements such as interleukin‐6, NFκB, and cellular adhesion molecules. In addition, increased adiposity triggers the release of adipokines such as leptin that can cause vascular remodeling and disruption of renal function. Insulin resistance can alter the balance between endogenous vasoactive molecules such as nitric oxide and reactive oxygen species, resulting in altered renal endothelial function. Moreover, hyperinsulinemia has direct renal effects such as induced relaxation of the afferent arteriole, resulting in glomerular hyperfiltration and renal damage. High insulin levels also stimulate angiogenesis and mesangial cell proliferation, associated with the development of diabetic nephropathy. Current evidence indicates a direct link between increased adiposity and insulin resistance with renal vascular injury; however, further investigation into the renal microvascular effects of obesity and insulin resistance are required to better understand this disease process.
Organization of the XYL genes in a thermophilic Bacillus species
Authors: Liao Wu‐Xiang , Earnest Linda , Kok Siew Ling , Jeyaseelan Kandiah 
Published: July 2007

AbstractThe organization of the genes involved in xylose catabolism in a thermophilic Bacillus sp. LW2 was found to be different from that of mesophiles such as B. subtilis and Escherichia coli. We have reported previously the cloning and characterization of the xylose isomerase gene (xylA) from this thermophilic Bacillus sp. A xylose transport permease gene (xylP) was located immediately upstream of xylA. This gene encoded a hydrophobic protein (392 amino acids) with a calculated molecular weight of 42,307. Further upstream of xylP, another related gene xylO encoding a sugar transport ATP‐binding protein was observed. A xylulose kinase gene (xylB) was identified downstream of xylA. Its open reading frame extended up to 1122 bp and represented a part (372 aa) of the enzyme. The order of the xyl genes in the thermophilic Bacillus sp. is therefore 5′‐xylO (ATP‐binding protein) ‐ xylP (xylose permease) ‐ xylA (xylose isomerase) ‐ xylB (xylulose kinase) ‐3′. The polarity of expression of these four genes was found to be unidirectional from xylO to xylB.
Protein phosphatases are pest containing proteins
Authors: Gomes Aldrin V. , Barnes Junor A. 
Published: July 2007

AbstractProtein phosphatases are required for removing phosphoryl groups in proteins involved in many physiological processes. Investigation of these enzymes for regions rich in proline (P), glutamic acid (E), serine (S) and threonine (T), called PEST regions showed that greater than 85% of the phosphatases investigated contained these regions. These regions are believed to be signals for degradation and could possibly serve as regulators of the intracellular localization and catalytic activity via limited proteolysis or as conditional signals for rapid degradation of these proteins by the ATP/ubiquitin‐dependent and/or the ATP non‐ubiquitin dependent proteolytic pathway. Many of these phospbatases were also found to contain a pentapeptide sequence bioehemically related to the KFERQ motif which targets proteins for lysosomal degradation which suggest that several pathways may exist for the degradation of protein phosphatases.
Proton‐donative antioxidant activity of fucoxanthin with 1,1‐Diphenyl‐2‐Picrylhydrazyl (DPPH)
Authors: Nomura Takaharu , Kikuchi Masako , Kubodera Akiko , Kawakami Yasushi 
Published: July 2007

AbstractReactions between a carotenoid, fucoxanthin and 1,1‐diphenyl‐2‐picrylhydrazyl were investigated both under anoxic and aerobic conditions. Fucoxanthin equimolarly reacted with 1,1‐diphenyl‐2‐picrylhydrazyl under anoxic conditions. Under aerobic conditions, only a part of fucoxanthin consumed 1,1‐diphenyl‐2‐picrylhydrazyl and the degree of reaction fluctuated with repeated trials. β‐Carotene or other carotenoids, β‐cryptoxanthin, zeaxanthin, licopen and lutein, were also examined in the reaction with 1,1‐diphenyl‐2‐picrylhydrazyl under anoxic conditions. All these compounds scarcely reacted with 1,1‐diphenyl‐2‐picrylhydrazyl.
Effect of 4‐methylumbelliferone on cell‐free synthesis of hyaluronic acid
Authors: Nakamura Toshiya , Funahashi Masaru , Takagaki Keiichi , Munakata Hidekazu , Endo Masahiko , Tanaka Kanji , Saito Yoshiharu 
Published: July 2007

AbstractHuman skin fibroblasts were cultured in the presence of 0.5 mM 4‐methylumbelliferone for 12 h, and cell‐free synthesis of hyaluronic acid was performed using membrane‐rich fraction from the cells. The preincubation of the cells with 4‐methylumbelliferone reduced hyaluronic acid synthesis to 15% of that of non‐preincubated cells, although its chain length was not changed. On the other hand, without preincubation of the cells with 4‐methylumbelliferone, hyaluronic acid synthesis was not changed even when 4‐methylumbelliferone was added directly to the reaction mixture. These results suggest that 4‐methylumbelliferone represses the expression of hyaluronic acid synthase on the cell surface.
Adenosine deaminase activity in serum and pleural effusions of tuberculous and non‐tuberculous patients
Authors: Al‐Shammary F. J. 
Published: July 2007

AbstractIn a retrospective study Adenosine deaminase (ADA) was assayed in 86 serum samples and 12 pleural fluid samples of patients with pulmonary tuberculosis. Serum and pleural fluid ADA levels were also examined in a group of 38 non‐tuberculous patients with pleural effusion. Highly significant increases in both serum and pleural fluid ADA levels were noted in tuberculous patients when compared to both control enzyme cut‐off values and non‐tuberculous pleural effusion patients. Negative Ziehl‐Nielsen staining for acid fast bacilli and Purified Protein Derivative skin test results were obtained in 32.3% and 11.1% of the examined patients respectively. All these patients showed significantly elevated serum or pleural fluid ADA levels. It is hereby suggested that serum and pleural fluid ADA levels can in conjtmction with other tests, serve as a marker in patients of pulmonary tuberculosis.
The irradiation of hepatocytes with He‐Ne laser causes an increase of cytosolic free calcium concentration and an increase of cell membrane potential, correlated with it, both increases taking place in an oscillatory manner
Authors: Vacca R. A. , Moro L. , Petragallo V. A. , Greco M. , Fontana F. , Passarella S. 
Published: July 2007

AbstractIsolated hepatocytes were irradiated with Helium‐Neon laser (fluence: 0.24 Joules x cm‐2, fluence rate: 12 mW x cm‐2 and changes of both cytosolic free Ca2+ concentration and cell membrane potential were checked by measuring fura‐2 and bis‐oxonol fluorescence respectively. Irradiation resulted in an enhancement in cytosolic free Ca2+ concentration that requires the presence of Ca2+ in the phase outside hepatocytes; consistently an increase in cell membrane potential was measured correlated with it. Interestingly, the rate of increase of both cytosolic free Ca2+ concentration and cell membrane potential shows special time dependent features similar to those peculiar of oscillatory processes.
Transfer of cholesterol from macrophages to lymphocytes in culture
Authors: de Bittencourt Paulo Homem , Curi Rui 
Published: July 2007

AbstractA major feature of macrophage metabolism is its capacity to produce and export cholesterol. Several reports have shown that the manipulation of lymphocyte cholesterol content elicits important changes in lymphocyte proliferation. These findings lead to an inquiry as to whether macrophage‐derived cholesterol released into the lymphocyte surroundings may be transferred to the latter thus affecting lymphocyte function. In this study, cholesterol transfer from macrophages to lymphocytes was examined in vitro using rat cells in culture. The findings indicate that there may be a significant transfer of cholesterol from [4‐14C]cholesterol labeled resident peritoneal macrophages to mesenteric lymph node resting lymphocytes (up to 173.9±2.7 pmol/107 lymphocytes/107 macrophages when co‐cultivated for 48 h), in a lipoprotein‐dependent manner. This represents the mass transfer of ca. 17 nmoles of cholesterol molecules per 107 lymphocytes from 107 macrophages (calculated on the basis of specific radioactivity incorporated into macrophages after the pre‐labelling period), which suggests that macrophages are capable of replacing the whole lymphocyte cholesterol pool every 21 h. Moreover, an 111%‐increase in the total cholesterol content of lymphocytes was found after co‐cultivation with macrophages for 48 h. When compared to peritoneal cells, monocytes/macrophages obtained from circulating blood leukocytes presented a much higher cholesterol transfer capacity to lymphocytes (3.06±0.10 nmol/107 lymphocytes/107 macrophages co‐cultivated for 24h). Interestingly, inflammatory macrophages dramatically reduced their cholesterol transfer ability (by up to 91%, as compared to resident macrophages). Cholesterol transfer may involve a humoral influence, since it is not only observed when cells are co‐cultivated in a single‐well chamber system (cells in direct contact), but also in a two‐compartment system (where cells can communicate but not by direct contact). Co‐cultivation with macrophages decreased the basal incorporation of [2‐14C]thymidine into lymphocyte DNA and the addition of cholesterol to lymphocyte culture media also impaired the lymphocyte proliferative response to the mitogens concanavalin A (Con A) and bacterial lipopolysaccharide (LPS). The above results suggest that macrophages may transfer cholesterol to lymphocytes (from both lymph nodes and blood), thus regulating lymphocyte function by raising the intracellular cholesterol content and suppressing lymphocyte proliferative activity. If this is so, a modulatory role for the transfer of cholesterol in both physiological (e.g. immune response) and pathological conditions (e.g. atherosclerosis) may be postulated. This hypothesis is currently under investigation in our laboratory.
Menadione toxicity in Saccharomyces cerevisiae cells: Activation by conjugation with glutathione
Authors: Ządzinski Roland , Fortuniak Anna , Bartosz Grzegorz , Bilinski Tomasz , Grey Martin 
Published: July 2007

AbstractMenadione (2‐methyl‐1,4‐naphthoquinone) has been used extensively as an oxidant stressor at the cellular level. However, the mechanism of cytotoxicity of this compound still remains controversial. This study deals with the role of intracellular glutathione in the resistance of the yeast Saccharomyces cerevisiae to menadione. Incubation with 0.5 mM menadione resulted in a decrease of total glutathione concentration in yeast cells, intracellular formation of menadione S‐glutathione conjugate and export of the conjugate from cells. GSH‐deficient mutants showed lower stimulation of superoxide and hydrogen peroxide production upon exposure to menadione and were more resistant to menadione than wild‐type isogenic strains. These results indicate that in yeast cells the formation of S‐glutathione conjugate is a major pathway of menadione metabolism and that this reaction leads to redox activation of menadione but permits its removal from the cells.
Heat stress affects the glucocorticoid receptor interaction with heat shock protein Hsp70 in the rat liver
Authors: Cvoro Aleksandra , Dundjerski Jadranka , Trajkovic Divna , Matic Gordana 
Published: July 2007

AbstractThe association of glucocorticoid hormones receptor (GR) with heat shock protein Hsp70 in the liver cytosol of rats exposed to 41°C whole body hyperthermic stress was examined by quantitative immunoblotting of the two proteins within immunopurified untransformed GR multiprotein complexes. The presence of Hsp70 in the rat liver GR heterocomplexes was confirmed, and 2‐fold increase in the Hsp70 relative to the steroid binding protein content within the complexes was recorded 2 and 12 h after the stress. This increase exceeded the stress‐induced elevation in the total cytoplasmic Hsp70 level, but could not be seen 24 h after the stress, when cytoplasmic Hsp70 returned to basal level. The results suggest that hyperthermic stress alters the composition of the rat liver untransformed GR heterocomplexes increasing the Hsp70 share.
Cys25‐nitrosylation inactivates papain
Authors: Venturini Giorgio , Fioravanti Emanuela , Colasanti Marco , Persichini Tiziana , Ascenzi Paolo 
Published: July 2007

AbstractNitric oxide (NO) may modulate the catalytic activity of cysteine proteases. In the present study, the inhibitory effect of NO, released by the NO‐donors (±)‐(E)‐4‐ethyl‐2‐[(E)‐hydroxyimino]‐5‐nitro‐3‐hexenamide and nitroprusside, on papain action is reported. Papain inactivation via NO‐mediated nitrosylation of the Cys25 catalytic residue represents a molecular model for cysteine protease inhibition.
Changes of nuclear membrane fluidity during rat liver regeneration
Authors: Tomassoni Maria‐Letizia , Albi Elisabetta , Magani Mariapia Viola 
Published: July 2007

AbstractWe have previously shown that the nuclear membrane fluidity is affected by lipid composition changes and that is very high, particularly in the hydrophobic core. The aim of this work is to study the modifications of nuclear membrane fluidity in relation to the cell cycle. Since compensatory hepatic growth is an informative and well characterised model for natural cell proliferation, the nuclear membrane fluidity, detected by two fluorescent probes, was studied at various regenerating times, ranging from 0 to 30 hours after partial hepatectomy. At 18 hours after partial hepatectomy the nuclear membrane fluidity increased and at 30 hours the higher values of hydrophobic core fluidity were observed. The behaviour of fluidity was related to the nuclear membrane neutral‐sphingomyelinase activity and, then, to the content of sphingomyelin. Therefore, the significant changes of the nuclear membrane fluidity and of the neutral‐sphingomyelinase activity found during rat liver regeneration suggested a their likely role in signal transduction pathways implying cell regeneration.
Oxidized Lipoproteins in Blood Plasma: Possible Marker of Atherosclerosis Progression
Authors: Moriel Patricia , Okawabata Fabio S. , Abdalla Dulcineia S. P. 
Published: July 2007

AbstractOxidized lipoproteins and antioxidants were detected during the course of hypercholesterolemia development in cholesterol‐fed rabbits. Lipid peroxides in blood plasma and very‐low‐, low‐, and high‐density lipoproteins (beta‐VLDL, LDL, and HDL) were increased during the course of hypercholesterolemia. The content of phospholipid peroxides increased in beta‐VLDL and LDL in parallel to that of cholesterol, whereas the amount of alpha‐tocopherol was decreased either in lipoproteins or blood plasma. Ascorbate and urate concentrations were also decreased. Lipid peroxides were positively correlated with volume and area of atherosclerotic lesions, suggesting a relation between the concentrations of lipid peroxides in blood plasma and the progression of atheromatous lesions.
Copper‐Dependent Oxidative Stress and Neurodegeneration
Authors: Rotilio G. , Carr` M. T. , Rossi L. , Ciriolo M. R. 
Published: July 2007

AbstractCopper is an essential trace element, but its redox reactivity leads to risks of damage to cell and tissues. These are well exemplified by several forms of neurodegenerative diseases, either arising as inherited disorders of copper metabolism, such as Menkes' and Wilson's disease, or as conformational diseases such as Alzheimer's disease and prion diseases. This review will cover some aspects of the involvement of copper‐mediated oxidative stress in degenerative processes in the central nervous system, with special focus on the familial form of amyotrophic lateral sclerosis (FALS). Furthermore, a possible role of copper reactivity in inducing critical steps in the apoptotic pathways leading to neurodegeneration is envisaged.
Mitochondrial Production of Hydrogen Peroxide Regulation by Nitric Oxide and the Role of Ubisemiquinone
Authors: Boveris Alberto , Cadenas Enrique 
Published: July 2007

AbstractMitochondria are considered the major cellular site for hydrogen peroxide production, a process that is kinetically controlled by the availability of oxygen and nitric oxide to cytochrome oxidase and of ADP to F1‐ATPase. The multisite regulation of mi1 tochondrial respiration and energy‐transducing pathways support a critical regulatory role of mitochondrion in cell signaling pathways. The cellular steady‐state levels of hydrogen peroxide and the role of mitochondria in maintaining these levels are reviewed.
In Vitro Binding Analysis of Hepatitis B Virus preS‐derived Putative Helper T‐cell Epitopes to MHC Class II Molecules Using Stable HLA‐DRB1*0405/‐DRA*0101 Transfected Cells
Authors: Kim Jung‐hwan , Park Jung‐hyun , Lee Yun‐Jung , Cho Eun‐wie , Bae Yong‐soo , Kim Kil Lyong 
Published: July 2007

AbstractIn designing epitope‐based vaccines, the inclusion of a helper T‐lymphocyte (HTL) epitope is necessary to elicit both humoral and cellular immune responses. Whereas the preS region of the hepatitis B virus (HBV) surface antigen is well‐known to raise protective immunity, the epitopes for activating HTLs are poorly characterized. In an attempt to identify such epitopes, the HBV‐preS region was screened for peptide sequences with HLA‐DR4 binding motifs, and putative HTL candidate peptides were synthesized in a biotinylated form. Using L929 mouse fibroblasts stably transfected with HLA‐DRB1*0405 and HLA‐DRA*0101 cDNA, specific binding of the peptides was then detected using fluorescence‐conjugated streptavidin. The cell‐surface expression of HLA‐DR molecules on transfectants was confirmed by confocal microscopy, and quantitative analysis of candidate peptide binding was performed by fluorescence activated cell sorting. Among eight preS‐derived peptides, three candidate peptides?namely preS1(23‐33), preS1(62‐72), and preS1(76‐86)?showed good binding characteristics to HLA‐DR4 molecules, among which the preS1(23‐33) epitope was regarded as the most promising HTL epitope. Further studies with these candidate HTL stimulatory peptides will show their ability to activate the human immune system against HBV.
A shell element for finite strain analyses: hyperelastic material models
Authors: Toscano Rita G. , Dvorkin Eduardo N. 
Published: July 2007

PurposeThis paper aims to develop a simple and efficient shell element for large strains hyper‐elastic analyses.Design/methodology/approachBased on the classical MITC4 shell element formulation a 3D shell element with finite strain kinematics is developed. The new quadrilateral shell element has five dof per node and two global dof to model the thickness stretching. The shell element is implemented for hyperelastic material models and the application of different hyperelastic constitutive relations is discussed.FindingsThe results obtained considering three of the hyperelastic material models available in the literature are quite different when the developed strains are relatively high; this indicates that, for analyzing actual engineering examples, experimental data should be used to decide on the most suitable constitutive relation.Originality/valueThe 3D version of the MITC4 element was developed.
Human capital value creation practices of software and service exporter firms in India
Authors: Murthy Vijaya , Abeysekera Indra 
Published: July 2007

PurposeThe purpose of this study is to explore the human capital (HC) value creation practices of knowledge‐based software and service exporter industry in India.Design/methodology/approachThe study used HC disclosure attributes as a tool to the contents of the annual reports for the year 2003‐2004, to evaluate the type and amount of HC disclosed by the software firms. The study also conducted semi‐structured interviews with the heads of human resources (HR) of 14 software firms to obtain a greater understanding of the similarities between reporting and managed HC practices.FindingsThe study identified most reported and least reported attributes of HC using content analysis and explained their reporting of value creation using interviews and resource‐based view. The findings suggest that the HC reporting practices were consistent with interview findings. The frequency of HC attributes reported followed the extent of the management's perception of HC value creation to the firm.Research limitations/implicationsThe limitations of the study are: first, it is a cross‐sectional study; second, the findings may be applicable exclusively to the software and service industry in India and cannot be generalised to other industries in India or software industry in other countries; third, the assertions by the HR heads are assumed to faithfully reflect the firm's HC practices; fourth, the study assumes that annual reports are the primary documents available to public (stakeholders) requiring information on the firms.Originality/valueThis study provides an insight into the HC reporting practices of the nascent software and service exporter industry in India that is experiencing an economic boom that is positively influenced by the information technology software industry. This study throws light on the utilization of HC for value creation by the top software firms. This may help countries having tie‐up with Indian firms to understand the value creation process of these firms to sustain growth. The study would enable other software firms to understand HC reporting practices of the industry, and could use a framework that is similar to the framework used in this study.