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21.
Obese persons are at increased cardiovascular risk and exhibit increased arterial stiffness and impaired endothelial function of large‐ and medium‐size arteries. We hypothesized that normotensive subjects suffering from severe obesity would also present remodeling and endothelial dysfunction of small resistance arteries. A total of 16 lean (age: 49.6 ± 2.9 years, BMI: 22.9 ± 0.3 kg/m2, mean ± s.e.m.) and 17 age‐matched severely obese (BMI: 41.1 ± 2.3 kg/m2) normotensive subjects were investigated. None had glucose or lipid metabolic abnormalities except for insulin resistance. Resistance arteries, dissected from abdominal subcutaneous tissue, were assessed on a pressurized myograph. For superimposable blood pressure, the media thickness, media cross‐sectional area (CSA), and media‐to‐lumen ratio values of resistance arteries were markedly and significantly greater in obese compared to lean subjects (media thickness 26.3 ± 0.6 vs. 16.2 ± 0.6 µm, CSA 22,272 ± 1,339 vs. 15,183 ± 1,186 µm2, and media‐to‐lumen ratio 0.113 ± 0.006 vs. 0.059 ± 0.001, respectively, P < 0.01). Acetylcholine‐induced relaxation was impaired in vessels from obese subjects compared to the lean individuals (?40.4 ± 1.3%, P < 0.01), whereas endothelium‐independent vasorelaxation was similar in all groups. Stiffness of small arteries as assessed by the stress/strain relationship was similar in lean and severely obese subjects. We conclude that severe human obesity is associated with profound alterations in structural and functional characteristics of small arteries, which may be responsible for the presence of elevated cardiovascular risk and increased incidence of coronary, cerebrovascular and renal events reported in obesity.  相似文献   
22.
Cdc6 proteins play an essential role in the initiation of chromosomal DNA replication in Eukarya. Genes coding for putative homologs of Cdc6 have been also identified in the genomic sequence of Archaea, but the properties of the corresponding proteins have been poorly investigated so far. Herein, we report the biochemical characterization of one of the three putative Cdc6-like factors from the hyperthermophilic crenarchaeon Sulfolobus solfataricus (SsoCdc6-1). SsoCdc6-1 was overproduced in Escherichia coli as a His-tagged protein and purified to homogeneity. Gel filtration and glycerol gradient ultracentrifugation experiments indicated that this protein behaves as a monomer in solution (molecular mass of about 45 kDa). We demonstrated that SsoCdc6-1 binds single- and double-stranded DNA molecules by electrophoretic mobility shift assays. SsoCdc6-1 undergoes autophosphorylation in vitro and possesses a weak ATPase activity, whereas the protein with a mutation in the Walker A motif (Lys-59 --> Ala) is completely unable to hydrolyze ATP and does not autophosphorylate. We found that SsoCdc6-1 strongly inhibits the ATPase and DNA helicase activity of the S. solfataricus MCM protein. These findings provide the first in vitro biochemical evidence of a functional interaction between a MCM complex and a Cdc6 factor and have important implications for the understanding of the Cdc6 biological function.  相似文献   
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Several indole derivatives, that were highly potent ligands of GluN2B-subunit-containing N-methyl-d-aspartate (NMDA) receptor, also demonstrated antioxidant properties in ABTS method. In particular, the 2-(4-benzylpiperidin-1-yl)-1-(5-hydroxy-1H-indol-3-yl)ethanone (1) proved to be a dual-effective neuroprotective agent. With the aim to increase the antioxidant properties we added a catechol moiety onto piperidine moiety. The designed hybrid derivative 3,4-dihydroxy-N-[1-[2-(5-hydroxy-1H-indol-3-yl)-2-oxoethyl]piperidin-4-yl]benzamide (10) was the most effective antioxidant agent (>94.1 ± 0.1% of inhibition at 17 μM) and showed GluN2B/NMDA receptor affinity at low micromolar concentration (IC50 0.66 μM). By means of computational studies we explored the effect of the presence of this antioxidant fragment during the recognition process to binding pocket.  相似文献   
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Interdependence between sperm concentration, motility, morphology, and the percentage of aneuploid sperm was explored to test whether oligoasthenoteratospermia (OAT) may have a multiple origin in idiopathic infertile males. A total of 174 men (age, 35.8 +/- 4.3 yr) with idiopathic infertility were studied. Seven patients had nonobstructive azoospermia, 55 had severe OAT, 30 had OAT, 27 had isolated alterations of motility, 45 had alterations of morphology and of motility, and 10 had isolated alterations of morphology. The sperm morphology was assessed with strict criteria. The percentage of aneuploid sperm was assessed with fluorescent in situ hybridization for chromosomes X, Y, 13, 15, 16, 17, 18, 21, and 22. Relationships between sperm features, and the relationship between sperm features and aneuploidies were analyzed with multivariate regression analysis. Statistical analysis did not find any significant relationship between the percentage of typical forms and sperm concentration or between morphology and motility. On the other hand, a positive and significant relationship was found between sperm concentration and motility. The percentage of aneuploid sperm was inversely and significantly related to the percentage of typical forms but not to motility and concentration. Sperm morphology is an independent characteristic with respect to concentration and motility, whereas it showed a significant inverse relationship with respect to the percentage of aneuploid sperm. This means that idiopathic OAT may occur by means of at least two independent pathways, the first affecting concentration and/or motility and the second affecting morphology.  相似文献   
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Intra bone marrow-bone marrow transplantation (IBM- BMT) + thymus transplantation (TT) has been shown to reduce the incidence of graft versus host disease (GVHD) and restore donor-derived T cell function. In addition, an increase in insulin sensitivity occurred in db/db mice after IBM-BMT+TT treatment. Heme oxygenase (HO)-1 is a stress inducible enzyme which exert antioxidant, antiapoptotic, and immune-modulating properties. We examined whether IBM-BMT+TT could modulate the expression of HO-1 in the kidneys of db/db mice. Six-week-old db/db mice with blood glucose levels higher than 250 mg/dl were treated with IBM-BMT+TT. Six weeks later, the db/db mice showed decreased body weight, blood glucose levels and insulin, and increased plasma adiponectin levels. The upregulation of HO-1 was associated with significantly (p<0.05) increased levels of peNOS and pAKT, but decreased levels of iNOS in the kidneys of db/db mice. Plasma creatinine levels also decreased (p<0.05), and the expression of type IV collagen was improved. Thus IBM-BMT+TT unregulated the expression of HO-1, peNOS and pAKT, while decreasing iNOS levels in the kidney of db/db mice. This was associated with an improvement in renal function.  相似文献   
29.
Deposition of amphiphilic porphyrin derivatives occurs spontaneously on silanised glass surfaces, in a controlled fashion. The resulting porphyrin films show appreciable fluorescence emission. This emission can be effectively quenched by immersion of the slides into a diluted solution of Hg(2+) (microM concentration). The initial intensity can be restored by washings with a solution of N,N,N',N'-tetrakis(2-pyridilmethyl)ethylenediammine with no loss of efficiency. A remarkable selectivity is featured toward the detection of Hg(2+) over Cu(2+), Cd(2+), Pb(2+) and Zn(2+) counterparts. This protocol can be extended to a flow-through apparatus. The presented results are of importance for the achievement of a solid-state chemosensor for mercuric ions, at micromolar concentration, in water.  相似文献   
30.
Fossil hominids often processed material held between their upper and lower teeth. Pulling with one hand and cutting with the other, they occasionally left impact cut marks on the lip (labial) surface of their incisors and canines. From these actions, it possible to determine the dominant hand used. The frequency of these oblique striations in an array of fossil hominins documents the typically modern pattern of 9 right‐ to 1 left‐hander. This ratio among living Homo sapiens differs from that among chimpanzees and bonobos and more distant primate relatives. Together, all studies of living people affirm that dominant right‐handedness is a uniquely modern human trait. The same pattern extends deep into our past. Thus far, the majority of inferred right‐handed fossils come from Europe, but a single maxilla from a Homo habilis, OH‐65, shows a predominance of right oblique scratches, thus extending right‐handedness into the early Pleistocene of Africa. Other studies show right‐handedness in more recent African, Chinese, and Levantine fossils, but the sample compiled for non‐European fossil specimens remains small. Fossil specimens from Sima del los Huesos and a variety of European Neandertal sites are predominately right‐handed. We argue the 9:1 handedness ratio in Neandertals and the earlier inhabitants of Europe constitutes evidence for a modern pattern of handedness well before the appearance of modern Homo sapiens.  相似文献   
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