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61.
Antonellis A Rogus JJ Canani LH Makita Y Pezzolesi MG Nam M Ng D Moczulski D Warram JH Krolewski AS 《Genomics》2002,79(3):326-332
Evaluating the potential genetic components of complex disease will likely be aided through the use of dense polymorphism maps. Previously, we reported evidence for linkage with diabetic nephropathy on chromosome 3q in a region encompassing the type 1 angiotensin II receptor (AGTR1) gene. To further investigate any role for this gene in disease onset, we set out to design a dense polymorphism map spanning the AGTR1 locus for the purpose of association studies. Toward this goal, we have developed a technique for rapid identification of polymorphisms in long stretches of genomic DNA. This approach uses long-range PCR, DNA pooling, and transposon-based DNA sequencing. Using this technique, we efficiently validated and genotyped 18 polymorphisms spanning the 60.5-kb AGTR1 locus. Our panel of polymorphisms has an average spacing of 3.2 kb and an average minor allele frequency of 24%. 相似文献
62.
Nikki Cecil M. Magdaong Dariusz M. Niedzwiedzki Rafael G. Saer Carrie Goodson Robert E. Blankenship 《BBA》2018,1859(10):1180-1190
A series of spectroscopic measurements were performed on membrane fractions and detergent-solubilized complexes from the green sulfur bacterium (GSB) Chlorobaculum (Cba.) tepidum. The excitation migration through the entire GSB photosynthetic apparatus cannot be observed upon excitation of membranes in the chlorosome region at 77?K. In order to observe energy transfer from the Fenna-Matthews-Olson (FMO) protein to the reaction center (RC), FMO was directly excited at ~800?nm in transient absorption experiments. However, interpretation of the results is complicated by the spectral overlap between FMO and the RC. The availability of the Y16F FMO mutant, whose absorption spectrum is drastically different from that of the WT, has enabled the selection of spectral regions where either only FMO or the RC contributes. The application of a directed kinetic modeling approach, or target analysis, revealed the various decay and energy transfer pathways within the pigment-protein complexes. The calculated FMO-to-RC excitation energy transfer efficiencies are approximately 25% and 48% for the Y16F and WT samples, respectively. 相似文献
63.
In between-subjects studies on two groups of women of the same age, we show that women assess male's facial attractiveness differently in the follicular (F) and luteal (L) phases. In the high conception risk phase (F), women tended to give higher scores to male faces than when they were in the luteal phase. During the five first days of the cycle, i.e. when the estrogen level is still low, women assessed men's facial attractiveness relatively highly. We suggest that it is progesterone in the luteal phase that is responsible for lower attractiveness assigned then to male faces. We also tested which anthropometric facial traits or indices influence male attractiveness. We found that assessments of attractiveness were correlated only with mouth height (positively) and the angle between the middle of the mouth and the middle of the eyes (negatively). The results are compared with those from other studies and discussed in the light of evolutionary biology. 相似文献
64.
Woclawek-Potocka I Bah MM Korzekwa A Piskula MK Wiczkowski W Depta A Skarzynski DJ 《Experimental biology and medicine (Maywood, N.J.)》2005,230(3):189-199
Phytoestrogens acting as endocrine disruptors may induce various pathologies in the female reproductive tract. The purpose of this study was to determine whether phytoestrogens present in the soybean and/or their metabolites are detectable in the plasma of cows fed a diet rich in soy and whether these phytoestrogens influence reproductive efficiency and prostaglandin (PG) synthesis during the estrous cycle and early pregnancy in the bovine endometrium. In in vivo Experiment 1, we found significant levels of daidzein and genistein in the fodder and their metabolites (equol and p-ethyl-phenol) in bovine serum and urine. The mean number of artificial inseminations (AIs) and pregnancy rates in two kinds of herds, control and experimental (cows fed with soybean 2.5 kg/day), were almost double in the soy-diet herd in comparison with the control animals. In in vivo Experiment 2, three out of five heifers fed soybean (2.5 kg/day) became pregnant whereas four out of five heifers in the control group became pregnant. The concentrations of a metabolite of PGF2alpha (PGFM) were significantly higher in the blood plasma of heifers fed a diet rich in soybean than those in the control heifers throughout the first 21 days after ovulation and AI. The higher levels of PGFM were positively correlated with equol and p-ethyl phenol concentrations in the blood. In in vitro experiments, the influence of isoflavones on PG secretion in different stages of the estrous cycle was studied. Although all phytoestrogens augmented the output of both PGs throughout the estrous cycle, equol and p-ethyl-phenol preferentially stimulated PGF2alpha output. The results obtained lead to the conclusion that soy-derived phytoestrogens and their metabolites disrupt reproductive efficiency and uterus function by modulating the ratio of PGF2alpha to PGE2, which leads to high, nonphysiological production of luteolytic PGF2alpha in cattle during the estrous cycle and early pregnancy. 相似文献
65.
Matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs), beta-chemokines, increased oxidative stress (SOX) and inflammation have been implicated as important factors in atherosclerosis and vascular remodeling. We hypothesized the possible roles of beta-chemokines [monocyte chemoattractant protein-1 (MCP-1), macrophage inflammatory proteins (MIP-1alpha, MIP-1beta) and regulated upon activation, normal T-cell expressed and secreted (RANTES)] as regulators of the metabolism of the vascular extracellular matrix in conditions of increased SOX in hemodialysis (HD) patients. We compared pre-dialysis levels of MMP-9/TIMP-1 system, beta-chemokines, Cu/Zn superoxide dismutase (Cu/Zn SOD) as a marker of SOX and C-reactive protein (CRP) as a marker of inflammation in HD patients with and without cardiovascular disease (CVD) to those of controls. HD patients, particularly those with CVD, showed a significant increase in values of Cu/Zn SOD, CRP, TIMP-1, TIMP-1/MMP-9 ratio, MCP-1 and MIP-1beta, whereas RANTES levels were lower than in the controls. The levels of MIP-1alpha as well as MMP-9 in all HD groups were similar to the controls. The positive correlations were observed between the MMP-9/TIMP-1 system and beta-chemokines, SOX and inflammation in whole HD group and in the subgroup with CVD. Multivariate analysis showed that the duration of dialysis followed by Cu/Zn SOD, MIP-1alpha and beta levels were the significant positive predictors of TIMP-1. In conclusion, our data show that MMP-9/TIMP-1 system and beta-chemokines could cooperate in conditions of elevated SOX, which ultimately predisposes hemodialysis patients to accelerated atherosclerosis. 相似文献
66.
The arterial circle of the brain,its branches and connections in selected representatives of the Antilopinae 下载免费PDF全文
Hieronim Frąckowiak Dariusz Dębiński Marcin Komosa Maciej Zdun 《Journal of morphology》2015,276(7):766-771
The arterial circle of the brain, that is, the circle of Willis, and its branches in ruminants have been chiefly described in farm animals and only in selected wild species. In view of the deficit of information about this vascular region in numerous other species of the Ruminantia, the arteries of the encephalic base were analyzed in five antelope species representing different genera of the Bovidae, Antilopinae. Specimens of the following species were examined: springbuck (Antidorcas marsupialis), blackbuck (Antilope cervicapra), dik‐dik (Madoqua kirkii), saiga (Saiga tatarica), and oribi (Ourebia ourebi). Post‐autopsy material received from domestic zoological gardens was used to inject the bilateral common carotid arteries with a stained acetone solution of vinyl superchloride. When the material was polymerized, the specimens were macerated enzymatically. The process resulted in casts of arteries of the head and encephalic base on a skeletal scaffold. The investigations revealed that the bilateral components of the arterial circle of the brain, that is, the rostral cerebral artery and caudal communicating artery, arose from the division of the intracranial segment of the internal carotid artery, which emerges from the rostral epidural rete mirabile. The extracranial segment of the internal carotid artery was obliterated. In consequence of this process, the blood reaches the brain chiefly from the maxillary artery. The research proved that the arteries of the encephalic base in the Antilopinae are most similar to the vessels described in antelopes of Tragelaphus, Taurotragus, and Boselaphus genera and small domestic ruminants. However, they are different from the arterial pattern of the encephalic base in bovines and other species classified as the Bovini. J. Morphol. 276:766–771, 2015. © 2015 Wiley Periodicals, Inc. 相似文献
67.
Plewczynski D Tkacz A Wyrwicz LS Rychlewski L 《Bioinformatics (Oxford, England)》2005,21(10):2525-2527
The AutoMotif Server allows for identification of post-translational modification (PTM) sites in proteins based only on local sequence information. The local sequence preferences of short segments around PTM residues are described here as linear functional motifs (LFMs). Sequence models for all types of PTMs are trained by support vector machine on short-sequence fragments of proteins in the current release of Swiss-Prot database (phosphorylation by various protein kinases, sulfation, acetylation, methylation, amidation, etc.). The accuracy of the identification is estimated using the standard leave-one-out procedure. The sensitivities for all types of short LFMs are in the range of 70%. AVAILABILITY: The AutoMotif Server is available free for academic use at http://automotif.bioinfo.pl/ 相似文献
68.
69.
Katarzyna Ciach Marek Niedoszytko Anna Abacjew-Chmylko Izabela Pabin Przemyslaw Adamski Katarzyna Leszczynska Krzysztof Preis Hanna Olszewska Dariusz G. Wydra Rita Hansdorfer-Korzon 《PloS one》2016,11(1)
Objective
To present current guidelines regarding treatment of mastocytosis in pregnancy on the example of observed patients.Design
Case control national study.Setting
Polish Center of the European Competence Network on Mastocytosis (ECNM).Population or Sample
23 singleton spontaneous pregnancies in 17 women diagnosed with mastocytosis in years 1999–2014, before becoming pregnant.Methods
Prospective analysis outcomes of pregnancies and deliveries.Main Outcome Measures
Survey developed in cooperation with the Spanish Instituto de Estudios de Mastocitosis de Castilla-La Mancha (CLMast), Hospital Virgen del Valle, Toledo, Red Espańola de Mastocitosis (REMA), Spain.Results
All 23 pregnancies resulted from natural conception. Obstetrical complications recorded in the first trimester included spontaneous miscarriage (5 pregnancies). Four patients delivered preterm, including one delivery due to preeclampsia at 26 weeks which resulted with neonate death due to extreme prematurity. Five women delivered via cesarean: four due to obstetrical indications and one due to mastocytosis, during which no anesthesia related complications were recorded. Of patients delivering vaginally, two received extradural anesthesia, three required oxytocin infusion due to uterine hypotonia. No labor complications were recorded. In one woman with pregnancy-induced hypertension, early puerperium was complicated by the presence of persistent arterial hypertension. One neonate was born with the signs of cutaneous mastocytosis. Another neonate was diagnosed with Patau syndrome. Four women were treated for mastocytosis prior to conception and continued therapy after becoming pregnant. One patient was put on medications in the first trimester due to worsening of her symptoms. Pregnancy exerted only a slight effect on the intensity and frequency of mastocytosis-related symptoms observed. Worsening of the disease-related symptoms was documented in only four patients (23%). None of the patients showed the signs of anaphylaxis, either before becoming pregnant, or during pregnancy and puerperium.Conclusions
There is no contraindication to pregnancy when mastocystosis-related pathologies are under appropriate medical control. 相似文献70.
Kitowska K Zakrzewicz D Königshoff M Chrobak I Grimminger F Seeger W Bulau P Eickelberg O 《American journal of physiology. Lung cellular and molecular physiology》2008,294(1):L34-L45
Lung fibrosis is characterized by increased deposition of ECM, especially collagens, and enhanced proliferation of fibroblasts. l-arginine is a key precursor of nitric oxide, asymmetric dimethylarginine, and proline, an amino acid enriched in collagen. We hypothesized that l-arginine metabolism is altered in pulmonary fibrosis, ultimately affecting collagen synthesis. Expression analysis of key enzymes in the arginine pathway, protein arginine methyltransferases (Prmt), arginine transporters, and arginases by quantitative (q) RT-PCR and Western blot revealed significant upregulation of arginase-1 and -2, but not Prmt or arginine transporters, during bleomycin-induced pulmonary fibrosis in mice. HPLC revealed a concomitant, time-dependent decrease in pulmonary l-arginine levels. Arginase-1 and -2 mRNA and protein expression was increased in primary fibroblasts isolated from bleomycin-treated mice, compared with controls, and assessed by qRT-PCR and Western blot analysis. TGF-beta1, a key profibrotic mediator, induced arginase-1 and -2 mRNA expression in primary and NIH/3T3 fibroblasts. Treatment of fibroblasts with the arginase inhibitor, NG-hydroxy-l-arginine, attenuated TGF-beta1-stimulated collagen deposition, but not collagen mRNA expression or Smad signaling, in fibroblasts. In human lungs derived from patients with idiopathic pulmonary fibrosis, arginase activity was unchanged, but arginase-1 expression significantly decreased when compared with donor lungs. Our results thus demonstrate that arginase-1 is expressed and functionally important for collagen deposition in lung fibroblasts. TGF-beta1-induced upregulation of arginase-1 suggests an interplay between profibrotic agents and l-arginine metabolism during the course of lung fibrosis in the mouse, whereas species-specific regulatory mechanisms may account for the differences observed in mouse and human. 相似文献