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971.
Mallis LM Sarkahian AB Harris HA Zhang MY McConnell OJ 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2003,796(1):71-86
In recent years, consumption of herbal supplements as an alternative to pharmaceutical drug therapy has increased. For example, with the health claims labeling which describes the link between soy-protein and a reduced risk of coronary heart disease (CHD), the consumption of soy and soy-derived phytoestrogens has increased dramatically. That being said, the oral bioavailability of only a few soy phytoestrogens such as Daidzein and Genestein have been previously estimated. In this paper, we present the calculated percent of rat oral bioavailability of five soy-derived phytoestrogens (Genistein, Daidzein, Biochanin A, Coumestrol, and Zearalenone) in male Sprague-Dawley rats. The plasma quantitation required for the bioavailability calculation is performed by using a rapid on-line plasma extraction procedure for the quantitative analysis. To further speed up the analysis the rats were dosed using the 'n-in-one' (cassette) protocol. The rapid on-line extraction/quantitation methodology coupled to the cassette dosing analysis of phytoestrogens is the key point of this paper. The limit of quantitation (LOQ) for each compound was 1-1000 ng/ml with each plasma sample analysis taking less than 2 min. In general the percent oral bioavailability was determined to be between 11 and 28%. 相似文献
972.
Angiogenesis is the formation of new blood vessels from the pre-existing vasculature. However, the study of this complex process is often hampered by the lack of a suitable cell-based model and the tools to study the biochemical events that lead to new blood vessel growth. The most widely accepted model for angiogenesis is the in vivo rat corneal model. In this model, the cornea, which is normally an avascular tissue, is stimulated to undergo angiogenesis in response to silver nitrate cauterization or to the implantation of an exogenous angiogenic agent. The physical changes associated with the new vessel growth can be readily monitored visually, but the regulated biochemical events that result in the growth and remodeling of the new vessels are much more challenging to decipher. In this report, a proteomics approach is evaluated for its utility in deciphering the biochemical events during a time course of angiogenic stimulation. At various time points post-silver nitrate cautery, corneas were harvested, solubilized, and analyzed by two-dimensional gel electrophoresis. Protein expression profiles at the various stages of angiogenesis were compared to those of control corneas. One hundred and eleven differentially-expressed proteins were identified by either matrix-assisted laser desorption/ionization-time of flight mass spectrometry or liquid chromatography-coupled electrospray ionization tandem mass spectrometry. Many of the proteins up-regulated during the angiogenesis process were identified as blood-related proteins, thus validating the development of functional blood vessels in the normally avascular tissue of the cornea. Furthermore, detection of differentially-regulated proteins in cauterized versus control tissue clearly validated the utility of a proteomics approach to study this model of angiogenesis. However, in order to get at the key regulatory proteins in the angiogenesis process, it is clear that additional scale-up and enrichment approaches will be required. 相似文献
973.
Tumor microenvironment plays a critical role in tumor growth, angiogenesis, and metastasis. Differences in site of tumor implantation result in differences in tumor growth, metastasis, as well as response to chemotherapy. We hypothesized that tumor-induced angiogenic growth factor production into the plasma will also be influenced by site of tumor implantation. We evaluated the site-dependent production of angiogenic growth factors in the plasma of tumor bearing animals at two different sites of implantation. Plasma levels of tumor necrosis factor-alpha (TNF-alpha), basic fibroblast growth factor (bFGF), and vascular endothelial growth factor (VEGF) were evaluated in nude mice bearing A2780, SKOV-3, or OVCAR-3 human ovarian tumors, as well as Panc-1, AsPC-1, or BxPC-3 human pancreatic tumors grown as subcutaneous (SC) xenografts or in the intraperitoneal (IP) cavity. Plasma VEGF and bFGF levels produced by two ovarian tumor lines and two pancreatic tumor lines were substantially higher when the tumors were implanted in the IP cavity than in the SC space. These studies indicated that the site of tumor implantation was an important determinant in the production of plasma VEGF and bFGF levels. As more and more anti-angiogenic agents are developed, the need for appropriate animal models becomes apparent. These results suggest the demand for an appropriate model for the in vivo evaluation of anti-angiogenesis. 相似文献
974.
Schall DM Ishee JH Titlow LW 《Journal of strength and conditioning research / National Strength & Conditioning Association》2003,17(2):299-302
The purpose of this study was to investigate the effects of magnetic therapy in the form of shoe insoles on vertical jump, bench squat, 40-yd dash, and a soccer-specific fitness test performance. Subjects were 14 collegiate male soccer players who were pretested, retested 3 weeks later, and then placed into a double-blind control or treatment group using a matching procedure. The control group received magnetic shoe insoles with a rating of 125 gauss, and the treatment group received insoles with a rating of 600 gauss. Subjects wore the insoles during practice and games for 7 weeks and were then retested. Results indicated significant differences among test scores during the 3 time periods but not between the treatment and control groups. There was a decline in 40-yd dash performance from the initial evaluation (5.10 seconds) to the final evaluation (5.08 seconds). There were no other significant differences. Within the limitations of the study, magnetic therapy did not improve physical performance. 相似文献
975.
The increasing number of complete and nearly complete metazoan genome sequences provides a significant amount of material for large-scale comparative genomic analysis. Finding new effective methods to analyse such enormous datasets has been the object of intense research. Three main areas in comparative genomics have recently shown important developments: whole-genome alignment, gene prediction and regulatory-region prediction. Each of these areas improves the methods of deciphering long genomic sequences and uncovering what lies hidden in them. 相似文献
976.
Informative missingness of parental genotype data occurs when the genotype of a parent influences the probability of the parent's genotype data being observed. Informative missingness can occur in a number of plausible ways and can affect both the validity and power of procedures that assume the data are missing at random (MAR). We propose a bootstrap calibration of MAR procedures to account for informative missingness and apply our methodology to refine the approach implemented in the TRANSMIT program. We illustrate this approach by applying it to data on hypertensive probands and their parents who participated in the Framingham Heart Study. 相似文献
977.
Dimmock JR Padmanilayam MP Das U Zello GA Sharma RK Shrivastav A Selvakumar P Pasha MK Nienaber KH Lee JS Allen TM Santos CL Balzarini J De Clercq E 《Journal of enzyme inhibition and medicinal chemistry》2003,18(4):313-324
Various 1-arylidene-2-tetralones 1 had been shown previously to possess moderate cytotoxic properties unaccompanied by murine toxicity. The objective of the present investigation was to undertake different molecular modifications of representative members of series 1 with a view to discerning those structural features leading to increased potencies. All compounds were evaluated using human Molt 4/C8 and CEM T-lymphocytes as well as murine P388 and L1210 leukemic cells. The Mannich bases 2, 4, 5 and 7 possessed increased potencies compared to the corresponding unsaturated ketones 1 and in general were potent cytotoxics having IC50 values in the 0.2-10 microM range. QSAR using the cytotoxicity data for 2a-e suggested that potency was positively correlated with the size of the substituents in the arylidene aryl ring. Compounds 2a-f were evaluated using a panel of approximately 53 human tumour cell lines and, when all cell lines were considered, were more potent than the reference drug melphalan. In particular, marked antileukemic activity was displayed. Molecular modeling was utilized in order to evaluate whether the shapes of the different compounds contributed to the varying potencies observed. Representative compounds demonstrated minimal or no inhibiting properties towards human N-myristoyltransferase (NMT) and did not bind to calf thymus DNA. This study has revealed a number of unique lead molecules as candidate anti-neoplastic agents serving as prototypes for future development. 相似文献
978.
Dimmock JR Jha A Zello GA Sharma RK Shrivastav A Selvakumar P Allen TM Santos CL Balzarini J De Clercq E Manavathu EK Stables JP 《Journal of enzyme inhibition and medicinal chemistry》2003,18(4):325-332
A series of novel 3,5-bis(phenylmethylene)-1-(N-arylmaleamoyl)-4-piperidones 3 have been synthesized which displayed potent cytotoxicity towards human Molt 4/C8 and CEM T-lymphocytes as well as murine P388 and L1210 leukemic cells. In contrast, the related N-arylmaleamic acids 4 possessed little or no cytotoxicity in these four screens. Molecular modeling revealed certain interplanar and bond angles and interatomic distances which were perceived to contribute to the observed bioactivity as well as providing suggestions for future structural modifications of the piperidones 3. Evaluation of representative compounds in series 3 and 4 on the activity of human N-myristoyltransferase revealed that, at the maximum concentration utilized, namely 250 microM, only weak inhibiting properties were displayed by some of the compounds in series 4. Various members of series 3 and 4 were well tolerated in mice. 相似文献
979.
Moreland LW 《Arthritis research & therapy》2003,5(2):54-67
Although the predominant mechanism of intra-articular hyaluronan (hyaluronic acid) (HA) and hylans for the treatment of pain
associated with knee osteoarthritis (OA) is unknown, in vivo, in vitro, and clinical studies demonstrate various physiological effects of exogenous HA. HA can reduce nerve impulses and nerve sensitivity
associated with the pain of OA. In experimental OA, this glycosaminoglycan has protective effects on cartilage, which may
be mediated by its molecular and cellular effects observed in vitro. Exogenous HA enhances chondrocyte HA and proteoglycan synthesis, reduces the production and activity of proinflammatory
mediators and matrix metalloproteinases, and alters the behavior of immune cells. Many of the physiological effects of exogenous
HA may be a function of its molecular weight. Several physiological effects probably contribute to the mechanisms by which
HA and hylans exert their clinical effects in knee OA. 相似文献
980.
Ghrelin stimulates feeding when administered centrally and peripherally. The lateral hypothalamus (LH) is thought to mediate ghrelin-induced hyperphagia. Thus, we examined central mechanisms underlying feeding generated by LH ghrelin. We determined that 0.3nmol of LH-injected ghrelin was the lowest dose increasing food consumption and it induced Fos immunoreactivity (IR; a marker of neuronal activation) in feeding-related brain areas, including the hypothalamic paraventricular, arcuate, and dorsomedial nuclei, amygdala, and nucleus of the solitary tract. Also, LH ghrelin induced Fos IR in LH orexin neurons. We conclude that the LH, as part of larger central circuitry, integrates orexigenic properties of ghrelin. 相似文献