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101.
A competitive inhibition-type enzymeimmunoassay (EIA) has been developed using 3-hemisuccinate-oestrone-peroxidase as conjugate for direct measurement of the hormone in swine urine. The method has a minimum detection level at 0.3 ng ml(-1) and satisfactory specificity, recovery and reproducibility. In a field trial with a group of 387 sows (7 in oestrus, 16 non-pregnant and 364 pregnant sows at several stages post service), it was shown that the assay is potentially an accurate pregnancy test in assessing the viability of the fetoplacental unit from day 23 up to day 30 post service. The assay is well suited for routine testing, particularly as a swine early pregnancy diagnosis test since urine sampling is easier and does not disturb the animal, while in the present assay there is no restriction in the time of sampling and the sample storage conditions. 相似文献
102.
Distribution of the molossinus allele of Sry, the testis-determining gene, in wild mice 总被引:3,自引:0,他引:3
Nagamine CM; Shiroishi T; Miyashita N; Tsuchiya K; Ikeda H; Takao N; Wu XL; Jin ML; Wang FS; Kryukov AP 《Molecular biology and evolution》1994,11(6):864-874
When the Y chromosome of the laboratory inbred mouse strain C57BL/6 (B6) is
replaced by the Y of certain strains of Mus musculus domesticus, testis
determination fails and all XY fetuses develop either as hermaphrodites or
XY females (XY sex reversal). This suggests the presence of at least two
alleles of Sry, the male-determining gene on the Y:M. m. domesticus and B6.
The B6 Y chromosome is derived from the Japanese house mouse, M. m.
molossinus and therefore carries a molossinus Sry allele. As a first step
to determine how the molossinus Sry allele evolved, its distribution
pattern was determined in wild mice. The cumulative data of 96 M. musculus
samples obtained from 58 geographical locations in Europe, North Africa,
and Asia show the molossinus Sry allele is restricted to Japan and the
neighboring Asian mainland and confirm that Japanese M. m. molossinus mice
were derived in part from a race of M. m. musculus from Korea or Manchuria.
Sry polymorphisms, as illustrated by the molossinus Sry allele, can serve
as molecular markers for studies on the evolution of wild M. musculus
populations and can help determine the role sex determination plays in
speciation.
相似文献
103.
This is the first report on the Robertsonian 1/29 translocation in the Sykia Chalkidiki cattle breed. The characteristics of this endangered breed are described, and the possibilities of rescuing and exploiting the breed in a zootechnical sense are examined. 相似文献
104.
Transposable elements induce spontaneous mutations, promote genome
rearrangements, regulate gene expression, and participate in the horizontal
spread of genes encoding traits such as antibiotic resistance among
bacterial genera too distantly related to undergo homologous recombination.
Here we review the bacterial transposon Tn5 and focus on those aspects of
its functional organization and transposition which provide insights into
how it and other elements may have arisen, proliferated, and evolved.
相似文献
105.
106.
Nicole Willems Frances C Bach Saskia G M Plomp Mattie HP van Rijen Jeannette Wolfswinkel Guy CM Grinwis Clemens Bos Gustav J Strijkers Wouter JA Dhert Bj?rn P Meij Laura B Creemers Marianna A Tryfonidou 《Arthritis research & therapy》2015,17(1)
IntroductionStrategies for biological repair and regeneration of the intervertebral disc (IVD) by cell and tissue engineering are promising, but few have made it into a clinical setting. Recombinant human bone morphogenetic protein 7 (rhBMP-7) has been shown to stimulate matrix production by IVD cells in vitro and in vivo in animal models of induced IVD degeneration. The aim of this study was to determine the most effective dose of an intradiscal injection of rhBMP-7 in a spontaneous canine IVD degeneration model for translation into clinical application for patients with low back pain.MethodsCanine nucleus pulposus cells (NPCs) were cultured with rhBMP-7 to assess the anabolic effect of rhBMP-7 in vitro, and samples were evaluated for glycosaminoglycan (GAG) and DNA content, histology, and matrix-related gene expression. Three different dosages of rhBMP-7 (2.5 μg, 25 μg, and 250 μg) were injected in vivo into early degenerated IVDs of canines, which were followed up for six months by magnetic resonance imaging (T2-weighted images, T1rho and T2 maps). Post-mortem, the effects of rhBMP-7 were determined by radiography, computed tomography, and macroscopy, and by histological, biochemical (GAG, DNA, and collagen), and biomolecular analyses of IVD tissue.ResultsIn vitro, rhBMP-7 stimulated matrix production of canine NPCs as GAG deposition was enhanced, DNA content was maintained, and gene expression levels of ACAN and COL2A1 were significantly upregulated. Despite the wide dose range of rhBMP-7 (2.5 to 250 μg) administered in vivo, no regenerative effects were observed at the IVD level. Instead, extensive extradiscal bone formation was noticed after intradiscal injection of 25 μg and 250 μg of rhBMP-7.ConclusionsAn intradiscal bolus injection of 2.5 μg, 25 μg, and 250 μg rhBMP-7 showed no regenerative effects in a spontaneous canine IVD degeneration model. In contrast, intradiscal injection of 250 μg rhBMP-7, and to a lesser extent 25 μg rhBMP-7, resulted in extensive extradiscal bone formation, indicating that a bolus injection of rhBMP-7 alone cannot be used for treatment of IVD degeneration in human or canine patients.
Electronic supplementary material
The online version of this article (doi:10.1186/s13075-015-0625-2) contains supplementary material, which is available to authorized users. 相似文献107.
Johannes HM Levels Boris Bleijlevens Farhad Rezaee Johannes MFG Aerts Joost CM Meijers 《Proteome science》2007,5(1):15-8
Background
High-Density Lipoprotein (HDL), one of the main plasma lipoproteins, serves as a docking station for proteins involved in inflammation, coagulation, and lipid metabolism. 相似文献108.
109.
Eric A Gaucher Logan G Graddy Tang Li Rosalia CM Simmen Frank A Simmen David R Schreiber David A Liberles Christine M Janis Steven A Benner 《BMC biology》2004,2(1):19
Background
Joining a model for the molecular evolution of a protein family to the paleontological and geological records (geobiology), and then to the chemical structures of substrates, products, and protein folds, is emerging as a broad strategy for generating hypotheses concerning function in a post-genomic world. This strategy expands systems biology to a planetary context, necessary for a notion of fitness to underlie (as it must) any discussion of function within a biomolecular system. 相似文献110.
Shui-Lian Yu Paul KS Chan Chun-Kwok Wong Cheuk-Chun Szeto Suzanne C Ho Karine So May MY Yu So-Fan Yim Tak-Hong Cheung Martin CS Wong Jo LK Cheung Apple CM Yeung Edmund K Li Lai-Shan Tam 《Arthritis research & therapy》2012,14(2):R80
IntroductionPrevalence of an abnormal Papanicolaou smear was significantly increased in lupus patients in cross-sectional studies, associated with a higher prevalence of high-risk human papillomavirus (HPV) infection. The nucleic acid-specific Toll-like receptors (TLRs) locate at the endolysosomal compartments and trigger the induction of cytokines for the innate immune response. This study evaluated whether abnormal host innate immune response in lupus patients may enhance HPV persistence.MethodsProtein levels of TLRs 3, 7, 8 and 9 in cervical epithelial cells of lupus patients and controls with or without HPV infection were assessed using flow cytometry. Characteristics associated with the differential expression of TLRs in systemic lupus erythematosus (SLE) were elucidated. The effect and interferon-stimulated genes (ISGs) (ISG15 and Mx-1) gene expressions were then measured in oncogenic HeLa (HPV18), CaSki (HPV) and C33A (HPV negative) cell lines using flow cytometry and quantitative real-time PCR. Ex vivo productions of cytokines and interferon-gamma (IFN-γ) upon TLR ligands stimulations were subsequently measured using cytometric bead array and ELISA.ResultsFor subjects with HPV infection, levels of TLR3 and TLR7 were significantly lower in lupus patients compared with controls. Significantly decreased TLRs 7, 8 and 9 levels were observed in HPV-negative SLE compared to healthy controls. For SLE with and without HPV infection, TLR7 and 9 levels were significantly lower in infected SLE than those in HPV-negative patients. Independent explanatory variables associated with down-regulation of TLR7 level included HPV infection and a higher cumulative dose of prednisolone; while a higher cumulative dose of hydroxychloroquine and HPV infection were associated with down-regulation of TLR9 level. In cervical cell lines, TLRs 3, 7, 8, 9 protein levels and antiviral ISG15 and Mx-1 gene expressions were inhibited in two oncogenic HPV types. Functional data showed that the induction of pro-inflammatory cytokines by TLR ligands (R837, ssRNA and ODN2395) was greatly impaired in CaSki and HeLa than C33A cells.ConclusionsIn conclusion, prednisolone and TLR antagonist (hydroxychloroquine) may down-regulate protein levels of TLR7 and TLR9 in lupus patients, thereby decreasing the innate immune response against HPV infection. Upon infection, HPV further down-regulate TLR7 and 9 levels for viral persistence. Furthermore, reduction of nucleic acid-sensing TLRs 7, 8 and 9 in carcinogenic HPVs ensures that the expression of inducible pro-inflammatory cytokines is minimized to prevent the expression of antiviral ISGs (ISG15 and Mx-1) on a biologically relevant antiviral response. 相似文献