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981.
Nociceptin-immunoreactive cellbodies were detected in the human trigeminal ganglion, while no such fibers were identified in the temporal artery or in dermal tissue from the neck region. In four healthy subjects receiving nociceptin into the temporal muscle in an open labeled design no pain was detected. In 10 healthy subjects who received 200pmol of nociceptin into tender non-dominant trapezius muscles in a placebo-controlled, randomized, balanced, and double-blinded design local tenderness increased (P=0.025) while no pain was noted. Thus, the action of nociceptin should be searched for in the trigeminal ganglion and/or in the central nervous system (CNS). 相似文献
982.
Forster P Röhl A Lünnemann P Brinkmann C Zerjal T Tyler-Smith C Brinkmann B 《American journal of human genetics》2000,67(1):182-196
Human Y-chromosomal short tandem repeat (STR) data provide a potential model system for the understanding of autosomal STR mutations in humans and other species. Yet, the reconstruction of STR evolution is rarely attempted, because of the absence of an appropriate methodology. We here develop and validate a phylogenetic-network approach. We have typed 256 Y chromosomes of indigenous descent from Africa, Asia, Europe, Australia, and highland Papua New Guinea, for the STR loci DYS19, DXYS156Y, DYS389, DYS390, DYS392, and DYS393, as well as for five ancient biallelic mutation events: two poly (A) length variants associated with the YAP insertion, two independent SRY-1532 mutations, and the 92R7 mutation. We have used our previously published pedigree data from 11,000 paternity-tested autosomal STR-allele transfers to produce a two-class weighting system for the Y-STR loci that is based on locus lengths and motif lengths. Reduced-median-network analysis yields a phylogeny that is independently supported by the five biallelic mutations, with an error of 6%. We find the earliest branch in our African San (Bushmen) sample. Assuming an age of 20,000 years for the Native American DYS199 T mutation, we estimate a mutation rate of 2.6x10-4 mutations/20 years for slowly mutating Y STRs, approximately 10-fold slower than the published average pedigree rate. 相似文献
983.
Doyonnas R Yi-Hsin Chan J Butler LH Rappold I Lee-Prudhoe JE Zannettino AC Simmons PJ Bühring HJ Levesque JP Watt SM 《Journal of immunology (Baltimore, Md. : 1950)》2000,165(2):840-851
The novel sialomucin, CD164, functions as both an adhesion receptor on human CD34+ cell subsets in bone marrow and as a potent negative regulator of CD34+ hemopoietic progenitor cell proliferation. These diverse effects are mediated by at least two functional epitopes defined by the mAbs, 103B2/9E10 and 105A5. We report here the precise epitope mapping of these mAbs together with that of two other CD164 mAbs, N6B6 and 67D2. Using newly defined CD164 splice variants and a set of soluble recombinant chimeric proteins encoded by exons 1-6 of the CD164 gene, we demonstrate that the 105A5 and 103B2/9E10 functional epitopes map to distinct glycosylated regions within the first mucin domain of CD164. The N6B6 and 67D2 mAbs, in contrast, recognize closely associated and complex epitopes that rely on the conformational integrity of the CD164 molecule and encompass the cysteine-rich regions encoded by exons 2 and 3. On the basis of their sensitivities to reducing agents and to sialidase, O-sialoglycoprotease, and N-glycanase treatments, we have characterized CD164 epitopes and grouped them into three classes by analogy with CD34 epitope classification. The class I 105A5 epitope is sialidase, O-glycosidase, and O-sialoglycoprotease sensitive; the class II 103B2/9E10 epitope is N-glycanase, O-glycosidase, and O-sialoglycoprotease sensitive; and the class III N6B6 and 67D2 epitopes are not removed by such enzyme treatments. Collectively, this study indicates that the previously observed differential expression of CD164 epitopes in adult tissues is linked with cell type specific post-translational modifications and suggests a role for epitope-associated carbohydrate structures in CD164 function. 相似文献
984.
The current study was designed to investigate possible effects of the platelet-derived growth factor (PDGF) receptor kinase blocker AG1295 on the development of interstitial fibrosis in rats with unilateral ureteral obstruction (UUO), monitored by ED-A+ fibronectin expression, the number of macrophages, and the presence of myofibroblasts as visualized by immunohistochemistry with monoclonal antibodies (mAb) IST9, mAb ED1, and mAb 1A4, respectively; interstitial fibrosis was quantified by Sirius-Red staining and computer-aided image analysis. Without AG1295 treatment, the Sirius-Red stained area of the control kidneys comprised 6.8ǃ.3% of the totally inspected area and increased to 19.0ǃ.9% in animals by 14 days and to 23.4ǃ.7% by 21 days after UUO. The number of macrophages increased from 4.3ǃ.1 in controls to 16.6DŽ.6 in animals at 14 days and to 23.2dž.4 at 21 days after UUO. This was accompanied by an increase in both ED-A+ fibronectin deposition and !-smooth muscle actin expression. Treatment with AG1295 (12 mg/kg body weight, daily i.p.) significantly reduced interstitial fibrosis as verified by a smaller Sirius-Red stained area (15.7ǃ.9% in animals at 14 days and 17.0ǂ.7% at 21 days after UUO) and also by a reduced number of macrophages (12.8ǃ.4 in animals at 14 days and 15.5Dž.8 at 21 days after UUO), and by the ED-A+ fibronectin deposition and the number of cells positive for !-smooth muscle actin. The study indicates that the PDGF receptor kinase blocker AG1295 is able to decrease interstitial fibrosis in the rat UUO model significantly. The diminution of early fibrosis mediators, i.e., macrophages, ED-A+ fibronectin, and myofibroblast phenotype, points to a modulated fibrosis process via a blockade of PDGF actions. 相似文献
985.
Regelin AE Fankhaenel S Gürtesch L Prinz C von Kiedrowski G Massing U 《Biochimica et biophysica acta》2000,1464(1):151-164
In order to investigate the relationship between lipid structure and liposome-mediated gene transfer, we have studied biophysical parameters and transfection properties of monocationic DOTAP analogs, systematically modified in their non-polar hydrocarbon chains. Stability, size and (by means of anisotropy profiles) membrane fluidity of liposomes and lipoplexes were determined, and lipofection efficiency was tested in a luciferase reporter gene assay. DOTAP analogs were used as single components or combined with a helper lipid, either DOPE or cholesterol. Stability of liposomes was a precondition for formation of temporarily stable lipoplexes. Addition of DOPE or cholesterol improved liposome and lipoplex stability. Transfection efficiencies of lipoplexes based on pure DOTAP analogs could be correlated with stability data and membrane fluidity at transfection temperature. Inclusion of DOPE led to rather uniform transfection and anisotropy profiles, corresponding to lipoplex stability. Cholesterol-containing lipoplexes were generally stable, showing high transfection efficiency at low relative fluidity. Our results demonstrate that the efficiency of gene transfer mediated by monocationic lipids is greatly influenced by lipoplex biophysics due to lipid composition. The measurement of fluorescence anisotropy is an appropriate method to characterize membrane fluidity within a defined system of liposomes or lipoplexes and may be helpful to elucidate structure-activity relationships. 相似文献
986.
Methylparaben induces malformations and alterations on apoptosis,oxidant–antioxidant status,ccnd1 and myca expressions in zebrafish embryos 下载免费PDF全文
Perihan Seda Ateş İsmail Ünal Ünsal Veli Üstündağ Ahmet Ata Alturfan Türkan Yiğitbaşı Ebru Emekli‐Alturfan 《Journal of biochemical and molecular toxicology》2018,32(3)
Methylparabens (MP) are widely used as preservatives in cosmetics, pharmacy, and food industry. Although acute toxicity studies in animals indicated that parabens are not significantly toxic, the effects of chronic exposure under sublethal doses are still unknown and the number of related studies is limited. Our aim was to evaluate the effects of MP on the development of zebrafish embryos focusing on development, locomotor activity, oxidant–antioxidant status, apoptosis, and ccnd1 and myca expressions. The expressions of ccnd1 and myca were determined by RT‐PCR. Lipid peroxidation (LPO), nitric oxide (NO), and glutathione‐S‐transferase (GST) activities were determined spectrophotometrically. Apoptosis was determined using acridine orange staining. Locomotor activity was measured using touch‐evoked movement test. MP exposure increased malformations, LPO, apoptosis, ccnd1 and myca expressions, and decreased GST activities and NO levels compared with the control group. Our findings will lead to further understanding of the mechanism of MP toxicity, and merit further research. 相似文献
987.
In this study, a method combining Raman spectroscopy with chemometric analysis was developed for detection of phage presence in raw milk and discrimination of Streptococcus thermophilus and Lactobacillus bulgaricus phages which are among the main phages causing problems in dairy industry. For this purpose, S. thermophilus and L. bulgaricus phages were added into raw milk separately, and then some pretreatments such as fat separation, removal of casein, and filtration were applied to the raw milk samples. Raman spectra of the samples were collected and then analyzed using principal component analysis in order to discriminate these phages in raw milk. In the next step, dilutions of S. thermophilus phages in pretreated raw milk were prepared, and Raman spectra were collected. These spectra were analyzed by using partial least squares method to quantify phages in low titer. Consequently, it has been demonstrated that S. thermophilus and L. bulgaricus phages, which have titers sufficient to fail the fermentation (~?107 pfu/mL) and have lower titers (102–103 pfu/mL), could be discriminated from antibiotic and each other. Additionally, low concentrations of S. thermophilus phages (102 pfu/mL) could be detected through Raman spectroscopy with a short analysis time (60 min) and high coefficient of determination (R2) values for both calibration (0.985) and validation (0.906) with a root mean square error of calibration of 70.54 and root mean square error of prediction of 165.47. However, a lower success was achieved with L. bulgaricus phages and the obtained coefficient of determination values were not sufficiently high (0.649). 相似文献
988.
From sludge obtained from the sewage digester plant in Stuttgart-Möhringen a strictly anaerobic bacterium was enriched and isolated with methyl chloride as the energy source. The isolate, which was tentatively called strain MC, was nonmotile, gram-positive, and occurred as elongated cocci arranged in chains. Cells of strain MC formed about 3 mol of acetate per 4 mol of CH3Cl consumed, indicating that the organism was a homoacetogenic bacterium fermenting methyl chloride plus CO2 according to:
The organism grew with 2–3% methyl chloride in the gas phase at a doubling time of near 30 h. Dichloromethane was not utilized. The bacterium also grew on carbon monoxide, H2 plus CO2, and methoxylated aromatic compounds. Optimal growth with methyl chloride was observed at 25°C and pH 7.3–7.7. The G+C-content of the DNA was 47.5±1.5%. The methyl chloride conversion appeared to be inducible, since H2 plus CO2-grown cells lacked this ability. From the morphological and physiological characteristics, the isolate could not be affiliated to a known species. 相似文献
989.
Thyrotropin-releasing hormone (TRH) is not thyrotropic but somatotropic in fed and starved adult chickens. 总被引:2,自引:0,他引:2
E R Kühn M Herremans E Dewil A Vanderpooten P Rudas T Bartha G Verheyen L Berghman E Decuypere 《Reproduction, nutrition, development》1991,31(4):431-439
Adult fed and starved Warren chickens, 2 yr of age, and approaching the end of the second laying year, were injected iv with 1 of the following products: 10 micrograms of thyrotropin releasing hormone (TRH); 100 micrograms of bovine thyrotropin (bTSH); 100 micrograms of ovine growth hormone (oGH); saline. The influence on plasma concentrations of thyroxine (T4), triiodothyronine (T3) or chicken GH (cGH) were followed. Prior to injection, it was clear from the control values that starvation for 3 d decreased plasma levels of T3 and increased cGH, whereas 7 d of fasting increased T4 and cGH. The plasma levels of cGH were elevated greater than 10-fold at 15 min following the TRH challenge in food-deprived chickens compared to a less than 4-fold increase in normal fed hens. This increase was followed by a rise in T3 after 1 h, which was also more pronounced in the starved animals, whereas T4 decreased or remained unaffected. Increases in T4 can, however, be obtained with 100 micrograms TSH in normal fed (2-fold) or starved animals (greater than 3-fold). Following injection of 100 micrograms oGH, a significant increase in T3 levels was observed which in fed animals was already present at 30 min, but the higher levels persisted for 1 and 2 h in fed and starved hens. At the same time, a decrease in T4 was observed in both groups of GH-treated chickens. It is concluded that TRH at the dose used is not thyrotropic but has a somatotropic effect and is responsible for the peripheral conversion of T4 into T3. 相似文献
990.
Samit Kumar Dutta Pedro Serrano Michael Geralt Herbert L. Axelrod Qingping Xu Scott A. Lesley Adam Godzik Ashley M. Deacon Marc‐André Elsliger Ian A. Wilson Kurt Wüthrich 《Protein science : a publication of the Protein Society》2015,24(10):1600-1608
Flavodoxins in combination with the flavin mononucleotide (FMN) cofactor play important roles for electron transport in prokaryotes. Here, novel insights into the FMN‐binding mechanism to flavodoxins‐4 were obtained from the NMR structures of the apo‐protein from Lactobacillus acidophilus (YP_193882.1) and comparison of its complex with FMN. Extensive reversible conformational changes were observed upon FMN binding and release. The NMR structure of the FMN complex is in agreement with the crystal structure (PDB ID: 3EDO ) and exhibits the characteristic flavodoxin fold, with a central five‐stranded parallel β–sheet and five α‐helices forming an α/β‐sandwich architecture. The structure differs from other flavoproteins in that helix α2 is oriented perpendicular to the β‐sheet and covers the FMN‐binding site. This helix reversibly unfolds upon removal of the FMN ligand, which represents a unique structural rearrangement among flavodoxins. 相似文献