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排序方式: 共有237条查询结果,搜索用时 31 毫秒
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Proteomic analysis of primary cell lines identifies protein changes present in renal cell carcinoma 总被引:6,自引:0,他引:6
Craven RA Stanley AJ Hanrahan S Dods J Unwin R Totty N Harnden P Eardley I Selby PJ Banks RE 《Proteomics》2006,6(9):2853-2864
New markers/targets for renal cell carcinoma (RCC) are needed to enable earlier detection and monitoring of disease and therapeutic targeting. To identify such molecules, normal and RCC-derived primary cell lines have been used as a simplified model system for studying changes that accompany tumorigenesis. Short-term cultures allow enrichment of relevant cell types from tissue samples, which is balanced against the potential for in vitro changes. Examination of 3 proteins with altered expression in RCC tissue showed the maintenance of normal-tumour differences in culture, although some changes were apparent, including alteration in the isoform of aldolase. Comparative analysis of primary cell lines by 2-DE found 43 proteins up-regulated and 29 down-regulated in at least three out of five tumour cell lines. Many of the observed changes have been previously reported in RCC, including up-regulation of several glycolytic enzymes, vimentin and heat shock protein 27, validating the approach. Additionally, several novel changes in protein expression were found, including up-regulation of several proteins involved in actin cytoskeleton organisation such as radixin and moesin, two members of the septin family, and the actin bundling protein, fascin. Validation studies using Western blotting and immunohistochemistry indicate that several of these molecules may be useful as markers for RCC. 相似文献
34.
Epidemiologic features of Lyme disease in New York 总被引:1,自引:0,他引:1
J P Hanrahan J L Benach J L Coleman E M Bosler J C Grabau D L Morse 《The Yale journal of biology and medicine》1984,57(4):643-650
During 1982, surveillance identified 207 cases of Lyme disease in New York State. Cases were clustered in two geographic areas, eastern Long Island and northern Westchester counties. Symptoms and signs of Lyme disease in cases were consistent with previous reports, with erythema chronicum migrans (ECM) being the most frequently (77 percent) reported sign of disease. Facial palsy was reported in a surprisingly high 18 percent of cases. Of 160 cases whose sera were submitted for Lyme spirochete specific IgG antibody testing, 112 (70 percent) had titers greater than or equal to 64, while 88 (55 percent) had titers greater than or equal to 128. Positive titers were not associated with any single sign or symptom of disease, but were significantly associated with symptom onset or tick bite occurring during the three-month period of June, July, and August. We conclude that the incidence of Lyme disease in New York is much higher than previously recognized. In addition, our data suggest that a serologic test for Lyme-spirochete IgG antibody lacks sensitivity, but can be useful in confirming the diagnosis of Lyme disease when antibody titers are high. 相似文献
35.
David?E?Comings Thomas?JH?Chen Kenneth?BlumEmail author Julie?F?Mengucci Seth?H?Blum Brian?Meshkin 《Theoretical biology & medical modelling》2005,2(1):50
Background
Attention Deficit Hyperactivity Disorder, commonly referred to as ADHD, is a common, complex, predominately genetic but highly treatable disorder, which in its more severe form has such a profound effect on brain function that every aspect of the life of an affected individual may be permanently compromised. Despite the broad base of scientific investigation over the past 50 years supporting this statement, there are still many misconceptions about ADHD. These include believing the disorder does not exist, that all children have symptoms of ADHD, that if it does exist it is grossly over-diagnosed and over-treated, and that the treatment is dangerous and leads to a propensity to drug addiction. Since most misconceptions contain elements of truth, where does the reality lie?Results
We have reviewed the literature to evaluate some of the claims and counter-claims. The evidence suggests that ADHD is primarily a polygenic disorder involving at least 50 genes, including those encoding enzymes of neurotransmitter metabolism, neurotransmitter transporters and receptors. Because of its polygenic nature, ADHD is often accompanied by other behavioral abnormalities. It is present in adults as well as children, but in itself it does not necessarily impair function in adult life; associated disorders, however, may do so. A range of treatment options is reviewed and the mechanisms responsible for the efficacy of standard drug treatments are considered.Conclusion
The genes so far implicated in ADHD account for only part of the total picture. Identification of the remaining genes and characterization of their interactions is likely to establish ADHD firmly as a biological disorder and to lead to better methods of diagnosis and treatment.36.
O'Meara CM Donovan A Hanrahan JP Duffy P Fair S Evans AC Lonergan P 《Theriogenology》2007,67(7):1262-1268
The role of seminal plasma (SP) components on the maintenance of motility, viability and fertilising ability of frozen-thawed spermatozoa is of considerable interest. However, differences observed in constituents of SP among males could explain differences in fertility obtained in vivo. Two experiments were designed to examine the effects of seminal plasma on fertility from cervically inseminated frozen-thawed semen. The objective of Experiment 1 was to investigate if source or type of SP influences pregnancy rate. Seminal plasma was collected from rams previously classified as having either High (HSP; n=3) or Low (LSP; n=3) fertility in vivo. Artificial SP (fructose/sodium solution with 10% BSA; ASP) was made. Frozen semen from the same 6 rams was thawed and inseminated (Control) or resuspended either in HSP, LSP or ASP (20% in semen) prior to insemination of ewes (n=284, over 2 farms). The overall pregnancy rate was 28.1%. Treatments (Control, ASP, HSP and LSP) were not significantly different (P>0.3). There was no difference between HSP and LSP (P>0.5), and no effect of using ASP compared to ram SP (P>0.7), on pregnancy rate. As there was no effect of SP on pregnancy rate a repeat experiment (Experiment 2) was designed to test the effect of washing and selecting motile sperm prior to resuspending in phosphate-buffered saline (PBS) containing SP on pregnancy rate. Frozen-thawed semen from each of 2 rams was centrifuged through a density gradient, pellets were centrifuged through a wash medium and the sperm concentration/ram was counted. Sperm cells were resuspended in: (1) control PBS, (2) PBS containing 30% HSP or (3) PBS containing 30% LSP to give 100 x 10(6) motile sperm in 0.25 mL. Control straws were thawed and inseminated directly. Ewes (n=223 over 2 farms) were inseminated 57 h post-sponge withdrawal and those not returning to oestrus were slaughtered 29-50 days post-insemination for pregnancy determination. In Experiment 2, the pregnancy rate for Control, PBS, HSP and LSP were 15.4%, 2.3%, 0% and 0%, respectively, for Farm 1 (P>0.05) and 17.8%, 11.0%, 3.9% and 12.4%, respectively, for Farm 2. Under the conditions of the current study, addition of SP from different donors of either High or Low fertility status to frozen-thawed ram semen post-thawing did not improve pregnancy rate in ewes. ASP had no effect on pregnancy rate in ewes when added to frozen-thawed semen. Washing and selection of motile sperm prior to resuspension in PBS with or without SP (30%) before insemination had a negative effect on pregnancy rate in cervically inseminated ewes. Hence, the addition of seminal plasma or some of its constituents to semen does not appear to improve pregnancy rate in cervically inseminated ewes. 相似文献
37.
Effects of Population Size and Selection Intensity on Correlated Responses to Selection for Postweaning Gain in Mice 下载免费PDF全文
Correlated responses to selection for postweaning gain in mice were studied to determine the influence of population size and selection intensity. Correlated traits measured were three-, six- and eight-week body weights, litter size, twelve-day litter weight, proportion infertile matings and two indexes of reproductive performance. In general, the results agreed with observations made on direct response: correlated responses in the body weight traits and litter size increased as (1) selection intensity increased and (2) effective population size increased. Correlated responses in the body weight traits and litter size were positive in the large population size lines (16 pairs), as expected from the positive genetic correlation between these traits and postweaning gain. However, several negative correlated responses were observed at small population sizes (one and two pairs). Within each level of selection intensity, traits generally associated with fitness tended to decline most in the very small populations (one and two pairs) and in the large populations (16 pairs) for apparently different reasons. The fitness decline at the small effective population sizes was attributable to inbreeding depression. In contrast, it was postulated that the fitness decline at the large effective population size was due to selection moving the population mean for body weight and a trait positively correlated genetically with body weight (i.e., percent body fat) away from an optimum. 相似文献
38.
Nasiara Karim Petrine Wellendorph Nathan Absalom Graham A. R. Johnston Jane R. Hanrahan Mary Chebib 《Amino acids》2013,44(4):1139-1149
GABAA receptors are members of the ligand-gated ion channel superfamily that mediate inhibitory neurotransmission in the central nervous system. They are thought to be composed of 2 alpha (α), 2 beta (β) subunits and one other such as a gamma (γ) or delta (δ) subunit. The potency of GABA is influenced by the subunit composition. However, there are no reported systematic studies that evaluate GABA potency on a comprehensive number of subunit combinations expressed in Xenopus oocytes, despite the wide use of this heterologous expression system in structure–function studies and drug discovery. Thus, the aim of this study was to conduct a systematic characterization of the potency of GABA at 43 human recombinant GABAA receptor combinations expressed in Xenopus oocytes using the two-electrode voltage clamp technique. The results show that the α-subunits and to a lesser extent, the β-subunits influence GABA potency. Of the binary and ternary combinations with and without the γ2L subunit, the α6/γ2L-containing receptors were the most sensitive to GABA, while the β2- or β3-subunit conferred higher sensitivity to GABA than receptors containing the β1-subunit with the exception of the α2β1γ2L and α6β1γ2L subtypes. Of the δ-subunit containing GABAA receptors, α4/δ-containing GABAA receptors displayed highest GABA sensitivity, with mid-nanomolar concentrations activating α4β1δ and α4β3δ receptors. At α4β2δ, GABA had low micromolar activity. 相似文献
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Kasthuri Kannayiram Vidhya Rekha Umapathy Y Chamundeswari JH Fathima Ramajayam Govindan Chella Perumal Palanisamy Vishnu Priya Veeraraghavan Selvaraj Jayaraman Ponnulakshmi Rajagopal 《Bioinformation》2022,18(3):80
Diabetes mellitus is a group of metabolic disorders that has risen to become the third most common cause in humans in recent years. The development of new bioactive substances from natural sources is a relatively new area. Flavonoids are believed to have a variety of beneficial properties in nature, including anti-inflammatory, antimicrobial, anticancer, antioxidant, neuroprotective, and anti-HIV properties. 15 naturally occurring flavonoids docked with the selected target aldose reductase. We report the optimal binding of Acumitin, Agathisflavone, Agehoustin B, and alpha-Toxicarol with aldose reductase for further consideration in drug discovery for T2DM. 相似文献