共查询到20条相似文献,搜索用时 15 毫秒
1.
G. C. S. Costa L. C. J. Alcantara R. Azevedo G. Muricy S. H. Kashima D. T. Covas B. Galvão-Castro S. R. Gadelha 《Molecular biology reports》2010,37(1):75-79
GLUT is the major glucose transporter in mammalian cells. Single nucleotide polymorphisms (SNP) at GLUT1 promoter and regulatory regions have been associated to the risk of developing nephropathy in different type 1 and type 2 diabetic populations. It has been demonstrated that differences in allelic and genotypic frequencies of GLUT1 gene (SLC2A1) polymorphisms occur among different populations. Therefore, ethnic differences in distribution of GLUT1 gene polymorphisms may be an important factor in determining gene-disease association. In this study, we investigated the XbaIG > T and HaeIIIT > C polymorphisms in six different Brazilian populations: 102 individuals from Salvador population (Northern Brazil), 56 European descendants from Joinville (South Brazil), 85 Indians from Tiryió tribe (North Brazil) and 127 samples from Southern Brazil: 44 from European descendants, 42 from African descendants and 41 from Japanese descendants. Genotype frequencies from both sites did not differ significantly from those expected under the Hardy–Weinberg equilibrium. We verified that the allele frequencies of both polymorphisms were heterogeneous in these six Brazilian ethnic groups. 相似文献
2.
To elucidate the role of amh and foxl2 in sex differentiation of the teleost fish Schizothorax kozlovi, the full-length cDNAs were cloned from the mature testis and ovary by rapid amplification of cDNA ends (RACE), and their relative mRNA expression levels were determined by quantitative real-time polymerase chain reaction among tissues and temperature groups. The complete amh and foxl2 cDNAs of S. kozlovi were 2060 bp and 1750 bp, which encoded 568 and 306 amino acids, respectively. The amh were expressed only in gonads, while foxl2 was expressed in the gills, brain and gonads, both exhibiting relatively high tissue specificity. The amh exhibited sex-specific expression pattern in the gonads. No sex differences in the foxl2 expression were observed in the brain and gonads, but significant sex differences were found in the gills. No significant differences were found in the foxl2 expression, from the larval to the juvenile stage, and also between different temperature groups. However, significant differences were found in the expression levels of amh from the larval (12–63 days posthatching (dph)) to the juvenile stage (190 dph), and also among the \(18{^{\circ }}\hbox {C}\) and \(10{^{\circ }}\hbox {C}\) groups at 31 dph. This result suggested that amh plays an important role in male sex differentiation of S. kozlovi during the early developmental stage, but no similar effect was observed in foxl2. 相似文献
3.
Ivayla N. Pantcheva Rumyana Zhorova Mariana Mitewa Svetlana Simova Heike Mayer-Figge William S. Sheldrick 《Biometals》2010,23(1):59-70
Alkaline-earth metal complexes of the monoanionic form of the polyether ionophore monensin A were isolated for the first time in solid state and were structurally characterized using various spectroscopic methods (IR, NMR, FAB-MS). The stoichiometric reaction of monensic acid (MonH) with M2+ (M = Mg, Ca) in the presence of an organic base leads to the formation of mononuclear complexes of composition [M(Mon)2(H2O)2]. The structures of magnesium (1) and calcium (2) monensin complexes in the solid state were established by single crystal X-ray crystallography. The complexes crystallize as [Mg(Mon)2(H2O)2]·5MeCN (1) and [Ca(Mon)2(H2O)2]·H2O·5MeCN (2) in the monoclinic P21 space group. The alkaline-earth metal ion is placed in a distorted octahedral environment, defined by two monensin anions acting as bidentate ligands in the equatorial plane of the complex as well as by two water molecules occupying the axial positions of the inner coordination sphere. The bactericidal activity of 1 and 2 was evaluated against aerobic Gram-positive microorganisms applying the double layer agar hole diffusion method. 相似文献
4.
L. A. Nesterova B. N. Manukhin 《Biochemistry (Moscow) Supplemental Series A: Membrane and Cell Biology》2009,3(1):66-70
The binding of specific nonselective α1- and α2-adrenoceptor antagonists [3H]prazosine and [3H]RX821002 has been studied on rat cerebral cortex synaptosomal membranes. It is shown that for α1-adrenoceptors the ligand-receptor interaction corresponds to the model assuming the presence of one pool of receptors and binding of two ligand molecules to the receptor. The parameters of [3H]prazosine binding to α1-adrenoceptors were: K d= 1.56 ± 0.17 nM, B max = 30.25 ± 1.78 fmol/mg protein, n = 2. The parameters of [3H]RX821002 binding to α2-adrenoceptors were: K d = 1.94 ± 0.08 nM, B max = 12.77 ± 3.17 fmol/mg protein, n = 2. For α2 -adrenoceptors the ligand-receptor interaction corresponded to the same model. For α1 - and α2-adrenoceptor antagonists the dissociation constants (K d) are approximately equal (1.56 ± 0.17 and 1.94 ± 0.08 nM, respectively), but the concentration of α2-adrenoceptors is two times lower than that of α1-adrenoceptors ( 12.77 ± 3.17 and 30.25 ± 1.78 fmol/mg protein, respectively). The efficiency (E = B max/2K d) of the ligand binding to α1-adrenoceptors is 2.3 times higher than that to α2-adrenoceptors (7.46 ± 1.32 and 3.29 ± 0.68 fmol/mg protein/nM, respectively. The data suggest that α1- and α2 -adrenoceptors in rat cerebral cortex exist as dimers. 相似文献
5.
V. G. Pshennikova N. A. Barashkov A. V. Solovyev G. P. Romanov E. E. Diakonov N. N. Sazonov I. V. Morozov A. A. Bondar O. L. Posukh L. U. Dzhemileva E. K. Khusnutdinova M. I. Tomsky S. A. Fedorova 《Russian Journal of Genetics》2017,53(6):688-697
Тhe DNA testing of autosomal recessive deafness type 1A (DFNB1A, MIM 220290) is complicated when deaf patients have only monoallelic (heterozygous) recessive mutations in the GJB2 (Сх26) gene that is uninformative for establishment of diagnosis. Such patients may be “random” heterozygous carriers of GJB2 mutations as well as have the mutant allele in a cis-regulatory region of GJB2 gene, in element genes encoding other connexins: GJB6 (Сх30) or GJB3 (Сх31). Previous studies of genetic causes of hearing loss in patients from Yakutia were directed to search for only mutations in the GJB2 gene, and the DNA diagnostics was uninformative for 9.7% (38/393) of the patients with monoallelic GJB2 mutations. In this work the search for mutations in genes GJB3 and GJB6 and two deletions с.del(GJB6-D13S1830) and с.del(GJB6-D13S1854) to the cis-regulatory region of GJB2 gene was conducted in 35 patients with GJB2 monoallelic mutations and in 104 normal hearing individuals. The genes studied are two synonymous substitution c.489G>A (р.Leu163Leu) (GJB6) and c.357C>T (р.Asn119Asn) (GJB3) have been found, probably do not have clinical significance, and two nonsynonymous substitution c.301G>A (p.Glu101Lys) (GJB6) and с.580G>A (p.Ala194Thr) (GJB3). Additional experimental evidences are needed for confirmation of pathogenic significance of detected nonsynonymous substitutions in development of hearing loss in studied patients. Diagnosis of the DFNB1A was confirmed in only one patient, who was discovered by the deletion с.del(GJB6-D13S1830) (GJB2) in combination with a recessive mutation с.35delG (GJB2). In general, our results indicate low contribution of mutations in genes GJB6 and GJB3 in hearing loss etiology in Yakutia. 相似文献
6.
Su Y Huang X Raskovalova T Zacharia L Lokshin A Jackson E Gorelik E 《Cancer immunology, immunotherapy : CII》2008,57(11):1611-1623
INTRODUCTION: We hypothesize that adenosine and PGE(2) could have a complementary immunosuppressive effect that is mediated via common cAMP-PKA signaling. MATERIALS AND METHODS: To test this hypothesis, the effect of adenosine and PGE(2) on the cytotoxic activity and cytokine production of lymphokine activated killer (LAK) cells was investigated. RESULTS: PGE(2) and adenosine inhibited LAK cells cytotoxic activity and production of INF-gamma, GM-CSF and TNF-alpha. In combination they showed substantially higher inhibition than each modality used alone. Using agonists and antagonists specific for PGE(2) and adenosine receptors we found that cooperation of PGE(2) and adenosine in their inhibitory effects are mediated via EP(2) and A(2A) receptors, respectively. LAK cells have 35-fold higher expression of EP(2) than A(2A). Combined PGE(2) and adenosine treatment resulted in augmentation of cAMP production, PKA activity, CREB phosphorylation and inhibition of Akt phosphorylation. Wortmannin and LY294002 enhanced the suppressive effects of adenosine and PGE(2). In contrast, Rp-8-Br-cAMPS, an inhibitor of PKA type I blocked their immunosuppressive effects, suggesting that the inhibitory effects of PGE(2) and adenosine are mediated via common pathway with activation of cAMP-PKA and inhibition of Akt. CONCLUSION: In comparison to other immunosuppressive molecules (TGF-beta and IL-10), adenosine and PGE(2) are unique in their ability to inhibit the executive function of highly cytotoxic cells. High intratumor levels of adenosine and PGE(2) could protect tumor from immune-mediated destruction by inactivation of the tumor infiltrating functionally active immune cells. 相似文献
7.
Godefroy E Wang Y Souleimanian NE Scotto L Stevanovic S Chen YT Valmori D Ayyoub M 《Cancer immunology, immunotherapy : CII》2007,56(8):1183-1192
Proteins encoded by genes of the SSX family are specifically expressed in tumors and are therefore relevant targets for cancer immunotherapy. One of the first identified family members, SSX-1, is expressed in a large fraction of synovial sarcomas as a fusion protein together with the product of the SYT gene. In addition, the full-length SSX-1 antigen is frequently expressed in tumors of several other histological types such as sarcoma, melanoma, hepatocellular carcinoma, ovarian cancer and myeloma. To date, however, SSX-1 specific T cell responses have not been investigated and no SSX-1 derived T cell epitopes have been described. Here, we have assessed the presence of CD4(+) T cells directed against the SSX-1 antigen in circulating lymphocytes of cancer-free individuals. After a single in vitro stimulation with a pool of peptides spanning the entire SSX-1 protein we could detect and isolate SSX-1-specific CD4(+) T cells from 5/5 donors analyzed. SSX-1-specific polyclonal populations isolated from these cultures recognized peptides located in three distinct regions of the protein containing clusters of sequences with significant predicted binding to frequently expressed MHC class II alleles. Characterization of specific clonal CD4(+) T cell populations derived from one donor allowed the identification of several naturally processed epitopes recognized in association with HLA-DR. These data document the existence of a significant repertoire of CD4(+) T cells specific for SSX-1 derived sequences in circulating lymphocytes of any individual that can be exploited for the development of both passive and active immunotherapeutic approaches to control disease evolution in cancer patients. 相似文献
8.
Khandekar Jishan Bari Shrikant Sharma Kandala V. R. Chary 《Biomolecular NMR assignments》2018,12(1):51-55
γS-crystallin is a major structural component of the human eye lens, which maintains its stability over the lifetime of an organism with negligible turnover. The G57W mutant of human γS-crystallin (abbreviated hereafter as γS-G57W) is associated with dominant congenital cataracts. In order to provide a structural basis for the ability of γS-G57W causing cataract, we have cloned, overexpressed, isolated and purified the protein. The 2D [15N–1H]-HSQC spectrum recorded with uniformly 13C/15N-labelled γS-G57W was highly dispersed indicating the protein to adopt an ordered conformation. In this paper, we report almost complete sequence-specific 1H, 13C and 15N resonance assignments of γS-G57W using a suite of heteronuclear 3D NMR experiments. 相似文献
9.
Smyk M Berg JS Pursley A Curtis FK Fernandez BA Bien-Willner GA Lupski JR Cheung SW Stankiewicz P 《Human genetics》2007,122(1):63-70
Deletion of the dosage sensitive gene NR0B1 encoding DAX1 on chromosome Xp21.2 results in congenital adrenal hypoplasia (AHC), whereas NR0B1 duplication in 46,XY individuals leads to gonadal dysgenesis and a female phenotype. We describe a 21-year-old 46,XY female
manifesting primary amenorrhea, a small immature uterus, gonadal dysgenesis, and notably absent adrenal insufficiency with
a submicroscopic (257 kb) deletion upstream of NR0B1. We hypothesize that loss of regulatory sequences may have resulted in position effect up-regulation of DAX1 expression,
consistent with phenotypic consequences of NR0B1 duplication. We propose that this genomic region and by extension those surrounding the dosage sensitive SRY, SOX9, SF1, and WNT-4 genes, should be examined for copy-number variation in patients with sex reversal.
M. Smyk and J. S. Berg contributed equally to this work. 相似文献
10.
In this study, the authors aimed to revise the ability of Solidago × niederederi, a hybrid between S. canadensis and S. virgaurea, to produce sexual ramets and seedlings as a part of its naturalization strategy. Based on a two-season garden cultivation experiment, we showed that the hybrid produces more generative ramets than vegetative ones and the number of generative ramets increases from one season to another with an increasing number of stem buds located on the caudices. We also revealed a spontaneous seedling recruitment by the hybrid during cultivation in the garden. Based on the seed germination test under laboratory conditions, we evidenced that the hybrid can reach a higher final germination percentage than S. canadensis but a lower one than S. virgaurea. Based on field studies conducted in 35 populations in Poland, the hybrid formed the largest populations in tree plantations and on abandoned fields, reaching 16.5 and 15.7 ramet clusters on average, respectively. The most abundant populations were found on abandoned fields; however, the mean number of ramets per cluster did not differ remarkably among habitats (H = 6.5, p = 0.163). In all populations, the mean number of vegetative ramets per cluster reached 0.85, while the generative ones achieved 6.43 on average. The statistical analysis proved that the aforementioned differences are significant (t = ?12.6, p = 0.0002). Our results suggest that S. × niederederi is able to generate its own offspring by sexual reproduction and that abandoned fields seem to be the most suitable habitats for its establishment. 相似文献
11.
Sungbong Shin Jinwook Lee Dave Rudell Kate Evans Yanmin Zhu 《Journal of Plant Growth Regulation》2016,35(3):655-666
12.
Yoko Yatabe Kaoru Yamamoto Chie Tsutsumi Wataru Shinohara Noriaki Murakami Masahiro Kato 《Journal of plant research》2011,124(2):265-268
The feasibility of later-generation hybrid production in ferns has not been previously studied, although it is a significant
factor in relation to reproductive isolation. Osmunda × intermedia, a hybrid between O. japonica and O. lancea, is semifertile and has moderate spore germination rates. Under the artificial conditions of this study, F2 and F3 offspring
were formed. Some of the F2 offspring showed precocity, and some of the F3 offspring also showed precocity. This fertility
suggests that introgressive hybridization might be ongoing in nature. This also indicates a currently unknown genetic control
over the timing of fertile frond production in Osmunda. 相似文献
13.
14.
The reproductive characteristics and pollination system of Rhododendron semibarbatum were investigated at two sites in Honshu, Japan. This species is protandrous, partially self-incompatible at postzygotic
stages, and requires outcrossing via pollinator visitation for effective seed production. The effective pollinators were two
bumblebee species: males of Bombus ardens at Miyama, and workers of Bombus honshuensis at Agematsu. The flowers possess two staminodes ornamented with whitish hairs, which do not reflect UV light, on the filaments.
Nectar was secreted continuously during the flowering period, and nectar production rate differed between the sites. Visitation
by B. ardens males was more frequent and varied among and within days, whereas that by B. honshuensis workers was less frequent and constant throughout the observation period. A single visit by a B. ardens male was more effective for seed production than visitation by a B. honshuensis worker, resulting in pollen limitation in the latter case. Differences in resource requirements between the two pollinators,
representing different castes, might affect their behavior, resulting in B. ardens males contributing to more effective seed production.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
15.
Alexandra Myari Nick Hadjiliadis Achilleas Garoufis Jaroslav Malina Viktor Brabec 《Journal of biological inorganic chemistry》2007,12(3):279-292
The interaction of the diastereomeric complexes Λ-[Ru(bpy)2(m-GHK)]Cl2 and Δ-[Ru(bpy)2(m-GHK)]Cl2 (bpy is 2,2′-bipyridine, GHK is glycine–l-histidine–l-lysine) with the deoxynucleotide duplex d(5′-CGCGATCGCG)2 was studied by means of 1H NMR spectroscopy. At a Δ-isomer to DNA ratio of 1:1, significant shifts for the metal complex are observed, whereas there is negligible effect on
the oligonucleotide protons and only one intermolecular nuclear Overhauser effect (NOE) is present at the 2D nuclear Overhauser
enhancement spectroscopy spectrum. The 1Η NMR spectrum at ratio 2:1 is characterized by a slight shift for the Δ-isomer’s bpy aromatic protons as well as significant shifts for the decanucleotide G4 H1′ and Η2″, A5 H2, G10 H1′, T6 NH and G2 NH protons. Furthermore, at ratio 2:1, 11 intermolecular NOEs are observed. The majority of the NOEs involve the sugar Η2′
and Η2″ protons sited in the major groove of the decanucleotide. Increasing the Δ-isomer to d(CGCGATCGCG)2 ratio to 5:1 results in noteworthy spectral changes. The Δ-isomer’s proton shifts are reduced, whereas significant shifts are observed for the decanucleotide protons, especially the
sugar protons, as well as for the exchangeable protons. Interaction is characterized by the presence of only one intermolecular
NOE. Furthermore, there is significant broadening of the imino proton signals as the ratio of the Δ-isomer to DΝΑ increases, which is attributed to the opening of the two strands of the duplex. The Λ-isomer, on the other hand, approaches the minor groove of the oligonucleotide and interacts only weakly, possibly by electrostatic
interactions. Photocleavage studies were also conducted with the plasmid pUC19 and a 158-bp restriction fragment, showing
that both diastereomers cleave DNA with similar efficiency, attacking mainly the guanines of the sequence probably by generating
active oxygen species.
Electronic supplementary material Supplementary material is available in the online version of this article at and is accessible for authorized users.
An erratum to this article can be found at 相似文献
16.
17.
Yu. B. Lishmanov L. N. Maslov E. I. Barzakh A. V. Krylatov P. R. Oltgen S. A. Browne M. Govindashvami 《Biology Bulletin》2009,36(4):354-362
Different subtypes of opioid receptors (OR) were activated in rats in vivo to study the activation effect on the heart’s resistance to ischemia and reperfusion. It has been established that administration of deltorphin II, a selective δ2-OR agonist, lowered the infarct size/area at risk index (IS/AAR) by 23%. Naltrexone, naloxone methiodide (an OR inhibitor not penetrating the blood-brain barrier (BBB)), and naltriben (δ2-antagonist) eliminated the cardioprotective effect of deltorphin II, while BNTX (a δ1-antagonist) produced no effect on the cardioprotective action of the δ2-agonist. The infarct-reducing effect of deltorphin II was eliminated by administration of chelerythrine (a protein kinase C (PKC) inhibitor), glibenclamide (a KATP-channels inhibitor), and 5-hydroxydecanoate (a mitochondrial KATP-channel blocker). Administration of other opioids did not reduce the IS/AAR index. It has been established that all the deltorphins manifest antiarrhythmic potency. Other opioids do not produce any effect on the incidence of arrhythmia occurrences. The antiarrhythmic effect of deltorphin II was eliminated by preliminary administration of naltrexone, naloxone methiodide, and naltriben, but BNTX did not affect the δ2-agonist’s anti-arrhythmic effect. The preliminary administration of chelerythrine, a PKC inhibitor, eliminated the δ2 agonist’s antiarrhythmic action. However, glibenclamide and 5-hydroxydecanoate did not alter the antiarrhythmic effect by deltorphin II. Therefore, activation of the peripheral δ2-ORs reduces the infarct size and prevents the onset of arrhythmias. The antiarrhythmic effect of the δ2-OR stimulation is mediated by activating PKC and opening the mitochondrial KATP-channels. PKC participates in the antiarrhythmic effect of the δ2-OR activation, but this effect does not depend on the condition of KATP-channels. 相似文献
18.
Repetitive sequence-based polymerase chain reaction (PCR) fingerprinting using the (GTG)(5) primer was applied for fast screening of bacterial strains isolated from dental plaque of early childhood caries (ECC)-affected children. A group of 29 Gram-positive bacteria was separated into a homogeneous cluster together with Streptococcus mutans reference strains and constituted an aberrant branch after the numerical analysis of (GTG)(5)-PCR fingerprints. Automated ribotyping with EcoRI restriction enzyme (RiboPrinter microbial characterization system) revealed high genetic heterogeneity among the tested group and proved to be a good tool for strain-typing purposes. Further characterization of the studied strains was achieved by extensive phenotyping and whole-cell protein fingerprinting and confirmed all the strains as S. mutans representatives. Obtained results showed rep-PCR fingerprinting with the (GTG)(5) primer to be a fast and reliable method for identification of S. mutans. 相似文献
19.
Beth A. Lawrence Shane C. Lishawa Yarency Rodriguez Nancy C. Tuchman 《Wetlands Ecology and Management》2016,24(4):457-467
Invasive wetland plants are the primary targets of wetland management to promote native communities and wildlife habitat, but little is known about how commonly implemented restoration techniques influence nutrient cycling. We tested how experimental mowing, herbicide application, and biomass harvest (i.e., removal of aboveground biomass) treatments of Typha-invaded mesocosms altered porewater nutrient (NO3 ?, NH4 +, PO 4 ?3 ) concentration and supply rate, vegetation response, and light penetration to the soil surface. We found that while herbicide application eliminated the target species, it also reduced native plant density and biomass, as well as increased porewater nutrient concentration (PO 4 ?3 , NO3 ?) and supply rates (N, P, K) up to a year after treatments were implemented. Because herbicide application promotes nutrient enrichment, it may increase the likelihood of reinvasion by problematic wetland invaders, as well as cause eutrophication and deleterious algal blooms in adjacent aquatic systems. Our data suggest that biomass harvest should be considered by managers aiming to reduce Typha abundance without eradicating native diversity, avoid nutrient leaching, as well as possibly utilizing biomass for bioenergy. 相似文献
20.
Nadiawati Alias Nor Muhammad Mahadi Abdul Munir Abdul Murad Farah Diba Abu Bakar Nik Azmi Nik Mahmood Rosli Md Illias 《World journal of microbiology & biotechnology》2009,25(4):561-572
A gene encoding endochitinase from Trichoderma virens UKM-1 was cloned and expressed in E. coli BL21 (DE3). Both the endochitinase gene and its cDNA sequences were obtained. The endochitinase gene encodes 430 amino acids
from an open reading frame comprising of 1,690 bp nucleotide sequence with three introns. The endochitinase was expressed
as soluble and active enzyme at 20°C when induced with 1 mM IPTG. Maximum activity was observed at 4 h of post-induction time.
SDS-PAGE showed that the purified endochitinase exhibited a single band with molecular weight of 42 kDa. Biochemical characterization
of the enzyme displayed a near neutral pH characteristic with an optimum pH at 6.0 and optimum temperature at 50°C. The enzyme
is stable between pH 3.0–7.0 and is able to retain its activity from 30 to 60°C. The presence of Mg2+ and Ca2+ ions increased the enzyme activity up to 20%. The purified enzyme has a strong affinity towards colloidal chitin and low
effect on ethyl cellulose and D-cellubiose which are non-chitin related substrates. HPLC analysis from the chitin hydrolysis
showed the release of (GlcNAc)3, (GlcNAc)2 and GlcNAc, in which (GlcNAc)2 was the main product. 相似文献