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71.
Carmina E.; Gentzschein E.; Stanczyk F.Z.; Lobo R.A. 《Human reproduction (Oxford, England)》1995,10(2):299-303
Serum C19 conjugates, specifically 3-androstanediol glucuronide(3G), reflect peripheral androgen action through the actionof 5-reductase activity. The origin of 5-reduced C19 conjugateshas been controversial and it has been suggested that they arederived primarily from adrenal androgens. We examined concentrationsof 3G, 3-androstanediol sulphate (3S), androsterone glucuronide(AoG) and androsterone sulphate (AoS) in 40 hirsute hyperandrogenicwomen. These patients were divided into four groups based uponindividual, combined or normal concentrations of the adrenalandrogens dehydroepiandrosterone (DHEAS) and 11-hydroxy-androstenedione.Testosterone, unbound testosterone and androstenedione weresimilar in these groups. Serum 3G was equally high in all groupsand was correlated significantly with hirsutism, while the otherconjugates were not. Androsterone glucuronide was raised inall groups but was higher in patients with raised DHEAS. Serum3S was raised in all groups and was higher where both adrenalandrogens were raised. Serum AoS was highly correlated withDHEAS. Serum 3G was correlated with unbound testosterone andandrostenedione but not with the adrenal androgens. The glucuronideconjugates were correlated with one another as were the sulphateconjugates but glucuronides and sulphates were not correlated.These data confirm ovarian and adrenal dependency of C19 conjugates.Serum 3G appears to reflect hirsutism most accurately and isleast dependent on adrenal androgens in patients with mixedhyperandrogenism. 相似文献
72.
ABSTRACT Coronaviruses (CoVs) mainly cause enteric and/or respiratory signs. Mammalian CoVs including COVID-19 (now officially named SARS-CoV-2) belong to either the Alphacoronavirus or Betacoronavirus genera. In birds, the majority of the known CoVs belong to the Gammacoronavirus genus, whilst a small number are classified as Deltacoronaviruses. Gammacoronaviruses continue to be reported in an increasing number of avian species, generally by detection of viral RNA. Apart from infectious bronchitis virus in chickens, the only avian species in which CoV has been definitively associated with disease are the turkey, pheasant and guinea fowl. Whilst there is strong evidence for recombination between gammacoronaviruses of different avian species, and between betacoronaviruses in different mammals, evidence of recombination between coronaviruses of different genera is lacking. Furthermore, the recombination of an alpha or betacoronavirus with a gammacoronavirus is extremely unlikely. For recombination to happen, the two viruses would need to be present in the same cell of the same animal at the same time, a highly unlikely scenario as they cannot replicate in the same host! 相似文献
73.
Summary Derepression of lysine biosynthetic enzymes of Saccharomyces cerevisiae was investigated in lys9 auxotrophs which lack saccharopine reductase activity. Five enzymes (homocitrate synthase, homoisocitrate dehydrogenase, -aminoadipate aminotransferase, -aminoadipate reductase and saccharopine dehydrogenase) were constitutively derepressed in all lys9 mutants with up to eight-fold higher enzyme levels than in isogenic wild-type cells. Levels of these enzymes in lys2, lys14, and lys15 S mutants were the same or lower than those in wild-type cells. The regulatory property of lys9 mutants exhibited recessiveness to the wild-type gene in heterozygous diploids. Unlike the mating type effect, homozygous diploids resulting from crosses between lys9 auxotrophs exhibited even higher levels of derepressed enzymes than the haploid mutants. Addition of a higher concentration of lysine to the growth medium resulted in reduction of enzyme levels although they were still derepressed. These results suggest that lys9 mutants represent a lesion for the saccharopine reductase and may represent a repressor mutation which in the wild-type cells simultaneously represses unlinked structural genes that encode for five of the lysine biosynthetic enzymes. 相似文献
74.
H Van Dekken E W Schervish J G Pizzolo W R Fair M R Melamed 《The Journal of pathology》1991,164(1):17-22
We have used fluorescent in situ hybridization and simultaneous in vivo bromodeoxyuridine labelling of a solid bladder cancer to examine tumour cell subsets for possible proliferative growth differences. In this dual-labelled preparation, most tumour cell nuclei exhibited monosomy 9, consistent with reported karyotypes of bladder cancer. Incorporated bromodeoxyuridine was visualized with a fluoresceinated antibody in 5-6 per cent of the tumour cells, concordant with S-phase estimates by cell cycle analysis of the flow cytometric DNA histogram. A majority of the bromodeoxyuridine-positive cells also carried the monosomy 9 chromosome abnormality. This is the first report to demonstrate the feasibility of combined in situ hybridization and detection of bromodeoxyuridine incorporated in vivo in human tumour cells in order to provide information on the growth rate of specific subsets of tumour cells identified by chromosomal constitution. 相似文献
75.
目的探讨血清sE—cad、CA724、CA199联合检测在胃癌诊断中的价值。方法应用酶联免疫吸附法(ELISA)技术检N30例正常对照组、35例良性胃病、45例胃癌患者血清sE—cad的含量,CA724和CA199则采用电化学发光技术检测。结果胃癌患者血清sE—cad、CA724和CA199的含量明显高于正常对照组和良性胃病组,差异有显著性(P〈0.01),三者联合检测敏感性、准确性均显著提高(P〈0.05)。结论血清sE—cad、CA724和CA199联合检测有助于提高胃癌诊断的敏感性和特异性。 相似文献
76.
Barnhart KT Stolpen A Pretorius ES Malamud D 《Human reproduction (Oxford, England)》2001,16(6):1151-1154
Topical, intravaginal microbicides and spermicides are greatly needed to prevent transmission of sexually transmitted diseases and/or unwanted pregnancies. The development of such compounds is a high research priority. The presumed method of action of existing, or novel, microbicides/spermicides is to provide a chemical barrier to the vaginal epithelium preventing exposure to micro-organisms. Other intravaginal products are used to treat vaginal bacteria of fungal infections. Little is known, however, about the actual or optimal initial distribution and subsequent spread of medications placed in the vagina. We describe a sensitive new technique to quantify the spread of a gel placed in the vagina using magnetic resonance imaging (MRI). Five millilitres of an over-the-counter spermicide containing Nonoxynol-9 was mixed with Gadolinium. MRI was used to quantify spread of the mixture 10 min after insertion with a standard applicator. We demonstrated contiguous spread of gel throughout the vagina. The coverage of material was thicker in the upper vagina than in the lower vagina. We also demonstrated, for the first time, that spermicidal compounds may migrate from the vaginal canal into the endocervix within 10 min of insertion. This finding suggests that topical microbicides/spermicides may act both in the vaginal canal and in the upper female genital tract. 相似文献
77.
Thivaratana Sinthuwiwat Chupong Ittiwut Thantrira Porntaveetus Vorasuk Shotelersuk 《American journal of medical genetics. Part A》2019,179(5):758-761
Female‐restricted syndromic intellectual disability (ID) is a neurodevelopmental disorder with developmental delay (DD)/ID, facial dysmorphism, and diverse congenital anomalies comprising heart defects, anal anomalies, choanal atresia, postaxial polydactyly, scoliosis, and brain abnormalities. Loss‐of‐function mutations in the USP9X gene inherited as X‐linked dominance were identified as its etiology in females of different ethnic groups. Here, we report a 15‐year‐old Thai girl harboring a novel de novo heterozygous one‐base pair deletion (c.3508delG, p.Val1170TrpfsX9) in exon 23 of USP9X. Her profound DD, dysmorphic face including attached earlobes, short stature, and congenital malformations including s‐shaped thoracolumbar scoliosis, hip dislocation, and generalized brain atrophy shared common characteristics of X‐linked syndromic ID. We have observed severely malformed oro‐dental organs and a choledochal cyst, which have never been reported. Our study presents the first patient from Thailand expanding the phenotypic and mutational spectra of the syndrome. 相似文献
78.
Alberto Utrero-Rico Javier Ruiz-Hornillos Cecilia González-Cuadrado Claudia Geraldine Rita Berta Almoguera Pablo Minguez Antonio Herrero-González Mario Fernández-Ruiz Octavio Carretero Juan Carlos Taracido-Fernández Rosario López-Rodriguez Marta Corton José María Aguado Luisa María Villar Carmen Ayuso-García Estela Paz-Artal Rocio Laguna-Goya 《The Journal of allergy and clinical immunology》2021,147(5):1652-1661.e1
79.
Y.?Takeda N.?Shiobara A.?R.?Saniabadi M.?Adachi K.?HiraishiEmail author 《Inflammation research》2004,53(7):277-283
Objective:Evolving evidence of anti-inflammatory effects is observed in patients with rheumatoid arthritis or ulcerative colitis following periodic adsorptive granulocyte and monocyte (GM) apheresis with a column containing cellulose acetate (CA) beads as apheresis carriers. This study was undertaken to obtain insights into mechanisms of anti-inflammatory actions of adsorptive GM apheresis with CA beads.
Methods:In a series of in-vitro experiments, we investigated the effects of plasma proteins and the leucocytes 2 integrin (CD18) on granulocyte adsorption to CA beads.
Results:Granulocyte adsorption to CA beads required plasma IgG, the complement C3 and was inhibited by an antibody to leucocytes CD18. Further, hepatocyte growth factor (HGF) and interleukin-1 receptor antagonist (IL-1ra) which have strong anti-inflammatory actions were released by granulocytes that adhered to CA beads.
Conclusions:Plasma IgG, C3 derived complement activation fragments and leucocytes CD18 are involved in granulocyte adhesion to CA beads and hence the release of HGF and IL-1ra.Received 27 October 2003; returned for revision 16 December 2003; accepted by M. J. Parnham 8 January 2004 相似文献
80.
The natural ligands of the S100 EF hand proteins S100A8 and A9 [myeloid-related proteins 8 and 14] have long been searched for in order to further the understanding of the role of the S100A8/A9-expressing monocyte subpopulation in progressing inflammatory processes. We demonstrate that S100A8, S100A9 and the S100A8/A9 heterodimeric complex bind to human dermal microvascular endothelial cell line (HMEC)-1 with an increasing binding capacity progressing from S100A8 < or = S100A9 < or = S100A8/A9. Similar results were obtained in the apolipoprotein E knockout mouse model, where preferably recombinant S100A9 but no S100A8 bound to the endothelium of the aorta ascendens. The binding of the S100A8/A9 heterodimer complex to activated HMEC-1 is specific as demonstrated by a dose-responding and satiable binding curve and the competition of FITC-labeled versus unlabeled protein. The protein character of the binding site was proven by treatment with trypsin. S100A8/A9 binding to HMEC-1 is inducible by lipopolysaccharide and tumor necrosis factor-alpha, and in the presence of calcium. A 163-kDa protein was isolated from a cell lysate of activated HMEC-1 cells using an affinity-chromatography protocol. The endothelial cell-associated ligand proteins isolated by the use of the S100A9 monomer and the S100A8/A9 dimer were subjected to mass spectrometry for protein identification. Clearly, alpha(2)-macroglobulin was identified as a binding partner for the S100A9 monomer, whereas no protein could be identified from the database for the ligand of the S100A8/A9 dimer. 相似文献