OBJECTIVE -To evaluate whether a 5-week low-glycemic index (LGI) diet versus a highglycemic index (HGI) diet can modify glucose and lipid metabolism as well as total fat mass in nondiabetic men.RESEARCH DESIGN AND METHODS -In this study, 11 healthy men were randomly allocated to 5 weeks of an LGI or HGI diet separated by a 5-week washout interval in a crossover design. RESULTS -TheLGI diet resulted in lower postprandial plasma glucose and insulin profiles and areas under the curve (AUCs) than the HGI diet. A 5-week period of the LGI diet lowered plasma triacylglycerol excursion after lunch (AUC, P Ͻ 0.05 LGI vs. HGI). These modifications were associated with a decrease in the total fat mass by ϳ700 g (P Ͻ 0.05) and a tendency to increase lean body mass (P Ͻ 0.07) without any change in body weight. This decrease in fat mass was accompanied by a decrease in leptin, lipoprotein lipase, and hormone-sensitive lipase RNAm quantities in the subcutaneous abdominal adipose tissue (P Ͻ 0.05).CONCLUSIONS -We concluded that 5 weeks of an LGI diet ameliorates some plasma lipid parameters, decreases total fat mass, and tends to increase lean body mass without changing body weight. These changes were accompanied by a decrease in the expression of some genes implicated in lipid metabolism. Such a diet could be of benefit to healthy, slightly overweight subjects and might play a role in the prevention of metabolic diseases and their cardiovascular complications. Diabetes Care 25:822-828, 2002T he insulin-resistance syndrome is a major risk factor for abnormal carbohydrate metabolism and atherosclerotic and coronary heart diseases (1). Recent prospective studies have incriminated the high-glycemic index (HGI) diet in the genesis of insulin resistance and type 2 diabetes (2). High postprandial plasma glucose and insulin excursions are assumed by some authors (3) to be independent predictors of risk for atherosclerotic diseases. Epidemiological evidence shows that the relationship between plasma glucose concentrations and cardiovascular diseases extends well below the glucose level defined for diabetes and even for impaired glucose tolerance. Therefore, interventions to reduce postprandial glycemia in the normal population could reduce the risk of developing atherosclerotic heart disease and/or diabetes. Dietary intervention might be one of the major approaches in diabetic patients' care, but it might even be useful in normal nondiabetic individuals.In diabetic subjects, the chronic consumption of a low-glycemic index (LGI) diet is generally found to improve plasma glucose and lipid profiles (4). In clinical practice, however, the chronic use of LGI foods is still questioned (5).In nondiabetic subjects, few data exist on the effects of short-and long-term consumption of LGI foods (6 -8). Behall et al. (6) demonstrated that an LGI diet resulted in a decrease in both glycemic area under the curve (AUC) and plasma cholesterol and triacylglycerol levels. Most of these studies, with one exception (8), have demonstrated beneficial effe...

Yeast centromere DNA (CEN) affinity column chromatography has been used to purify several putative centromere and kinetochore proteins from yeast chromatin extracts. The single yeast gene (CBF5) specifying one of the major low-affinity centromere-binding proteins (p64'/CBF5p) has been cloned and shown to be essential for viability ofSaccharomyces cerevisiae. CBF5 specifies a 55-kDa highly charged protein that contains a repeating KKD/E sequence domain near the C terminus, similar to known microtubule-binding domains in microtubule-associated proteins 1A and 1B. CBF5p A 240-kDa multisubunit protein complex (CBF3) that binds specifically to the CDEIII region of the yeast centromere has been purified and characterized (20). This protein complex is thought to be absolutely essential for centromere and kinetochore function, since it binds in vitro to the wild-type CEN sequence but not to a functionally inactive mutated CEN DNA that contains a single-base alteration in CDEIII (20,24). Affinity-purified CBF3 consists of at least three tightly associated subunits: 110 kDa (CBF3A), 64 kDa (CBF3B), and 58 kDa (CBF3C). Significantly, affinity-purified preparations of CBF3 contain an ATP-dependent motor activity that mediates movement of CEN DNA-coated microbeads along microtubules in a plus-to-minus direction (15). Thus, it is likely that CBF3 contains a kinetochore component that brings about attachment and movement of the chromosomes on the spindle microtubules. The gene (CBF2) encoding the 110-kDa subunit of this complex was cloned by using tryptic peptide sequences obtained from gel-purified CBF3A as a basis to prepare synthetic oligodeoxyribonucleotide hybridization probes, which were subsequently used to screen a yeast genomic library (17). At the same time, Goh and Kilmartin (12) cloned the identical gene by complementation of a conditional mutation (ndclO) leading to a defect in chromosome segregation. The CBF2/ NDC10 gene product is essential for viability of S. cerevisiae and for proper chromosome segregation. Although this protein contains a consensus nucleotide-binding site, no homologies to known molecular motors are apparent.In this paper, we describe the isolation of two yeast low-affinity centromere-binding proteins, topoisomerase II (Topo II) and CBF5p, and the cloning and sequencing of the CBF5 gene. The CBF5 protein contains a (KKD/E)n sequence domain highly homologous to known microtubulebinding domains in microtubule-associated protein 1A (MAP1A) and MAPlB (19,26). Evidence indicating that 4884 on May 12, 2018 by guest

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Yeast centromere DNA (CEN) affinity column chromatography has been used to purify several putative centromere and kinetochore proteins from yeast chromatin extracts. The single yeast gene (CBF5) specifying one of the major low-affinity centromere-binding proteins (p64'/CBF5p) has been cloned and shown to be essential for viability of Saccharomyces cerevisiae. CBF5 specifies a 55-kDa highly charged protein that contains a repeating KKD/E sequence domain near the C terminus, similar to known microtubule-binding domains in microtubule-associated proteins 1A and 1B, CBF5p, obtained by overexpression in bacterial cells, binds microtubules in vitro, whereas C-terminal deleted proteins lacking the (KKD/E)n domain do not. Dividing yeast cells containing a C-terminal truncated CBF5 gene, producing CBF5p containing only three copies of the KKD/E repeat, delay with replicated genomes at the G2/M phase of the cell cycle, while depletion of CBF5p arrests most cells in G1/S. Overproduction of CBF5p in S. cerevisiae complements a temperature sensitivity mutation in the gene (CBF2) specifying the 110-kDa subunit of the high-affinity CEN DNA-binding factor CBF3, suggesting in vivo interaction of CBF5p and CBF3. A second low-affinity centromere-binding factor has been identified as topoisomerase II.

Multicellular tumor spharoids (MCTS) are a widely used three-dimensional cell culture system with many advantages compared to monolayer cultures. The differentiation of tumor cells cultured as MCTS resembles more closely the in vivo-situation which is particularly true for their inner, so called quiescent region where tumor cells do not proliferate (leading to a differentiation and proliferation gradient). Most but not all MCTS develop a zone of central cell death until they have an appropriate size. Although this cell death was thought to be necrotic in nature due to insuficient oxygenation or nutrition it has been shown that the cells die at oxygen tensions which allow normal cell growth in monolayer culture. Therefore, we were looking if cells in MCTS die by apoptosis. In three colorectal adenocarcinoma cell lines (HRT-18, HT-29, CX-2) we could show by morphology, TUNEL-method and DNA-laddering that apoptosis in the quiescent area coincides the development of cell death in the center of the MCTS. Supposing that a putative CD95 ligand Will be produced in the quiescent area we studied the FadAF'O-l pathway. Two cell lines, HRT-18 and CX-2, expressed CD95 to the same degree. However, their sensitivities to anti-CD95 mediated apoptosis were different. Because HT-29 did not express CD95, other mechanisms must be active. Heat shock proteins (HSPs) are expressed in most tumor cells at high levels and are known to be regulated also by oxygen tension. It has been shown that members of the HSP70 family and some of the small HSPs have anti-apoptotic properties. Experiments with anti-sense mRNA against HSP7O done by WE1 et al. (Cancer Immunol lmmunother 40, 1995:73-8) revealed that the loss of HSP induce apoptosis.Surprisingly, we found that tumor cells in the quiescent region of MCTS loss all HSPs. These findings suggest that the loss of HSPs my be the initiator of apoptosis found in the quiescent area of MCTS. The regulation of HSPs during hypoxia and their relationship to apoptosis in tumor cells are currently under investigastion.It is wdl known that apoptosis is playing M important role in several disaws such as C(UKXT. In aging mrny alterations are ocmingat oelkrlarand organic M s . Our aim was to study the apoptosis of polymorphonuckar granulocytes (PMNLs), as a might play a role in several pathologies encountmcl with aging. houn of staik culture without ur with stidation. The agents used were: PMA, H202, FMLP, G-CSF, GM-CSF, GSH, LPS, modd,in&wdasevaal-. astheclpoptosis The PMNLa of herhhy young (20-2Syr~), middle (35-5oyrS) and elderly (65-~yn) W= studied for clpoptosiS &er 18IL2. The apoptosis was d by t a d stainiq ofthe platcsandbytlow cytometric mining. It was f d that witbout stimulrtion the susaptibility of PMNb to clpoptosis was slightlyincmscd with aging. Under various stimrlrrtions such as PMA, H& the apoptosk was almost IW?, the FMLP i f l c l w d also, white the other StimULnts d pment to diti;aenb extart the apoptosis. Marked age-rt!htai chngcswae obsesved in the extent of apoptosis under stimulatio...