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41.
Evidence for a major gene (RP10) for autosomal dominant retinitis pigmentosa on chromosome 7q: linkage mapping in a second,unrelated family 总被引:7,自引:0,他引:7
Rachel E. McGuire Alexandra M. Gannon Lori S. Sullivan Joseph A. Rodriguez Stephen P. Daiger 《Human genetics》1995,95(1):71-74
Retinitis pigmentosa is a genetically heterogeneous form of retinal degeneration, which has X-linked, autosomal recessive and autosomal dominant forms. The disease genes in families with autosomal dominant retinitis pigmentosa (adRP) have been linked to six loci, on 3q, 6p, 7p, 7q, 8q and 19q. In a large American family with late-onset adRP, microsatellite markers were used to test for linkage to the loci on 3q, 6p, 7p, 7q and 8q. Linkage was found to 7q using the marker D7S480. Additional microsatellite markers from 7q were then tested. In total, five markers, D7S480, D7S514, D7S633, D7S650 and D7S677, show statistically significant evidence for link-age in this family, with a maximum two-point lod score of 5.3 at 0% recombination from D7S514. These results confirm an earlier report of linkage to an adRP locus (RP10) in an unrelated family of Spanish origin and indicate that RP10 may be a significant gene for inherited retinal degeneration. In addition, we used recently reported microsatellite markers from 7q to refine the linkage map of the RP10 locus. 相似文献
42.
The maternal behaviour of three species of voles was compared using a semi-naturalistic laboratory system. Meadow vole females spent more time out of the nest, and exhibited less maternal behaviour in terms of nursing and brooding, and more non-social behaviour such as locomoting, eating, and drinking, than the females of the other two species. Across all species, maternal behaviour decreased from parturition onward, while non-social behaviour increased. Paternal care was well developed in the prairie vole and pine vole, but was never observed in the meadow vole. During the first postnatal week, male prairie voles showed a tendency to enter the nest when the female left the young unattended. This trend was not apparent in the male pine vole. The physical parameters of pup development, including eye opening and the development of fur, were similar in all three species. Behavioural development, however, was most rapid in the meadow vole, intermediate in the prairie vole, and slowest in the pine vole. These results are compared with those of previous field and laboratory studies, and are discussed with reference to the life-history strategy of each species. 相似文献
43.
Caprine Arthritis-Encephalitis Virus Is Distinct from Visna and Progressive Pneumonia Viruses as Measured by Genome Sequence Homology 总被引:5,自引:3,他引:2 下载免费PDF全文
Susan M. Roberson Travis C. McGuire Paula Klevjer-Anderson John R. Gorham William P. Cheevers 《Journal of virology》1982,44(2):755-758
Competitive inhibition of hybridization between 125I-labeled caprine arthritis-encephalitis viral RNA and homologous cDNA by heterologous viral RNA shows that the caprine retrovirus shares <20% genome sequence homology with visna and progressive pneumonia viruses. These viruses, however, are indistinguishable in immunodiffusion reactions involving the major structural protein (p28). 相似文献
44.
6,9-deepoxy-6,9,-(phenylimino)-delta 6,8-prostaglandin I1, (U-60,257), a new inhibitor of leukotriene C and D synthesis: in vitro studies 总被引:3,自引:0,他引:3
M K Bach J R Brashler H W Smith F A Fitzpatrick F F Sun J C McGuire 《Prostaglandins》1982,23(5):759-771
Addition of the calcium inophore, A 23187, and cysteine to isolated mononuclear cells from rat peritoneal washings causes a marked increase in the formation of thromboxane B2 (TxB2) along with the formation of leukotrienes C and D (LT's). The formation of LT's in this system was inhibited by 6,9-deepoxy-6,9-(phenylimino)-delta 6,8-prostaglandin I1, U-60,257, or its methyl ester, U-56,467, (ID50 4.6 and 0.31 microM, respectively). There was no inhibition of TxB2 formation. By contrast, two structurally-related compounds, PGI2 and its stable analog, 6-beta-PGI1, did not affect the formation of either LT's or TxB2. The inhibition of LT formation by U-60,257 was rapidly reversed after removal of this compound from the cells. U-60,257 did not inhibit the cyclooxygenase of human polymorphonuclear leukocytes. Nor did it inhibit formation of 12-L-hydroxy-5,8,10,14-eicosatetraenoic acid (12-HETE) in human platelets. On the other hand, U-60,257 inhibited glutathione S-transferase activity of rat basophil leukemia cells (ID50, 37 microM), suggesting that this compound may inhibit the last step in LTC biosynthesis. In addition to inhibiting LT synthesis, U-60,257 also appears to be a competitive inhibitor of the action of LT on the guinea pig ileum, although this inhibition requires a higher drug concentration than those ordinarily encountered during assay for LT's in U-60,257-treated incubations. 相似文献
45.
Bloodstream forms of Trypanosoma brucei that were infective for mammals, when grown in vitro at 37 C for 29 days or 25 months had amounts of variant surface glycoprotein similar to the amounts from bloodstream forms isolated from infected rat blood. The amounts were measured by competition radioimmunoassays for both unique and cross-reacting determinants and the results were the same, providing evidence that a single type of variant surface glycoprotein was measured. Neither radioimmunoassay detected determinants of variant surface glycoproteins in trypanosomes transformed by culturing at 27 C to insect forms not infective for mammals. 相似文献
46.
Daily injections of estradiol or the antiestrogen tamoxifen initially stimulate uterine weight increase and progesterone receptor synthesis, though continued tamoxifen fails to maintain the increased weight. The stimulatory actions of both estradiol and tamoxifen are inhibited or reversed by a single injection of progesterone. It has been hypothesized that progesterone antagonizes estrogen action by reducing estrogen receptor levels, but in the present experiments neither cytoplasmic nor nuclear estrogen receptor was affected. We conclude that progesterone acts at a point beyond estrogen receptor availability or translocation to antagonize estrogen action. 相似文献
47.
48.
Patrick E. McGuire 《Folia Geobotanica》1983,18(1):107-109
Elytrigia turcica sp. nov., (Poaceae) (2n=8x=56), a member of the polyploid complex related toE. elongata (Host) Nevski, (2n=2x=14), is described and distinguished fromE. pontica (Podp.) Holub, (2n=10x=70), which it most resembles. 相似文献
49.
Niels C. Krejci Lynne Smith Rebecca Rudd Robert Langdon Joseph McGuire 《In vitro cellular & developmental biology. Animal》1991,27(12):933-938
Summary To investigate the regulation of epithelial differentiation, normal human epidermal keratinocytes were cultured floating on
the surface of culture medium without attachment to a solid substrate. Keratinocytes spread out on the surface of the medium,
proliferated and differentiated either into several flat lacy sheets 1 to 3 cells thick (on medium containing 0.15 mM calcium) or formed one single aggregate of cells from 5 to 15 cells in thickness on medium containing 1.15 mM calcium. The cell aggregates demonstrated a pattern of ordered epithelial differentiation. Levels of progressive differentiation
resembling the structure of normal human epidermis were identified by light microscopy, immunohistochemistry, and electron
microscopy. Differentiation proceeded from cells at the air side toward cells at the medium side with basal appearing cells
on the air side and keratinocytes expressing filaggrin and involucrin on the side toward the medium. These results demonstrate
that organized epithelial differentiation can occur in the absence of extracellular matrix. In contrast with other air-liquid
interface cultures, epithelial differentiation in the absence of extracellular matrix progresses from air towards medium. 相似文献
50.
Richard Kvetansk David S. Goldstein Virginia K. Weise Courtney Holmes Katalin Szemeredi Gyorgy Bagdy Irwin J. Kopin 《Journal of neurochemistry》1992,58(6):2296-2302
In conscious animals, handling and immobilization increase plasma levels of the catecholamines norepinephrine (NE) and epinephrine (EPI). This study examined plasma concentrations of endogenous compounds related to catecholamine synthesis and metabolism during and after exposure to these stressors in conscious rats. Plasma levels of 3,4-dihydroxyphenylalanine (DOPA), NE, EPI, and dopamine (DA), the deaminated catechol metabolites 3,4-dihydroxyphenylglycol (DHPG), and 3,4-dihydroxyphenylacetic acid (DOPAC), and their O-methylated derivatives methoxyhydroxyphenylglycol (MHPG) and homovanillic acid (HVA) were measured using liquid chromatography with electrochemical detection at 1, 3, 5, 20, 60, and 120 min of immobilization. By 1 min of immobilization, plasma NE and EPI levels had already reached peak values, and plasma levels of DOPA, DHPG, DOPAC, and MHPG were increased significantly from baseline, whereas plasma DA and HVA levels were unchanged. During the remainder of the immobilization period, the increased levels of DOPA, NE, and EPI were maintained, whereas levels of the metabolites progressively increased. In animals immobilized briefly (5 min), elevated concentrations of the metabolites persisted after release from the restraint, whereas DOPA and catecholamine levels returned to baseline. Gentle handling for 1 min also significantly increased plasma levels of DOPA, NE, EPI, and the NE metabolites DHPG and MHPG, without increasing levels of DA or HVA. The results show that in conscious rats, immobilization or even gentle handling rapidly increases plasma levels of catecholamines, the catecholamine precursor DOPA, and metabolites of NE and DA, indicating rapid increases in the synthesis, release, reuptake, and metabolism of catecholamines. 相似文献