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1.
Probiotics and Antimicrobial Proteins - Gamma-aminobutyric acid (GABA) is a principal inhibitory neurotransmitter in the central nervous system and is produced by irreversible decarboxylation of...  相似文献   
2.
Russian Journal of Bioorganic Chemistry - A simple, convenient, environmentally benign method has been developed for the synthesis of spiro-5-cyanopyrimidines by multi-component condensation of...  相似文献   
3.
Monolayer formation of SaOS‐2 (human osteoblast‐like cells) was observed on VACNT (vertically aligned multiwalled carbon nanotubes) scaffolds without purification or functionalization. The VACNT were produced by a microwave plasma chemical vapour deposition on titanium surfaces with nickel or iron as catalyst. Cell viability and morphology studies were evaluated by LDH (lactate dehydrogenase) release assay and SEM (scanning electron microscopy), respectively. The non‐toxicity and the flat spreading with monolayer formation of the SaOs‐2 on VACNT scaffolds surface indicate that they can be used for biomedical applications.  相似文献   
4.
A bioassay-guided fractionation and chemical examination of chloroform extract of Plumbago capensis roots resulted in isolation and characterization of two new napthaquinone derivatives (4, 8) along with six known compounds (13, 57). Their structures were determined on the basis of extensive spectroscopic (IR, MS, 1D and 2D NMR) data analysis and by comparison with the literature data. All the compounds were tested for their mosquito larvicidal activity against fourth instar larvae of Aedes aegypti, and compared with that of rotenone. Among the tested compounds, isoshinanolone (3) and plumbagin (1) showed excellent toxicity with LC50 values of 1.26 and 5.43 μg/mL. New compound (8) displayed moderate toxicity against the tested mosquito species.  相似文献   
5.

Abstract  

An efficient stepwise synthesis of homo-oligomers and mixed oligomers of gabapentin and pregabalin on solid support using Fmoc-protected derivatives and HBTU/HOBt/DIEA as coupling agent is described. The synthesis was also carried out using solution phase methodology. The Gpn/Pgn homo oligomers and mixed oligomers forms C9 helix in solution as determined by NMR study. Chiral as well as achiral gamma amino acids were used for the synthesis of oligomers in order to investigate the secondary structural preferences.  相似文献   
6.
The immunophenotype of HT29 human colon cancer cells implanted into severe combined immunodeficient mice was assessed in primary tumours and their metastases in the lungs using an indirect immunohistochemical method. After primary tumours were surgically removed, the metastases were given time to develop, thus paralleling the clinical situation. While vimentin was negative in both primary and secondary tumours, E-cadherin was present as membrane-bound labelling in the primary tumours only. Whereas the markers p53, MIB1, PCNA and CEA were consistently positive in both primary and metastatic tumours, CD44 variant 6 and CA125 were negative in metastases but positive in the primary tumours. There was a significant increase in the percentage of cells labelled for p53 in the primary tumours compared with the metastases. For the proliferation markers, there was no significant difference in labelling between primary tumours and metastases for MIB1. Of the cytokeratins examined, CK 20 gave the strongest and most consistent reaction in both primary and secondary tumours. The results indicate that, for certain immunohistochemical markers, results are the same in both primary tumours and metastases. Hence, in these cases, antigens that are expressed on the primary tumour as well as on the metastases can serve as target molecules for immunologically based forms of treatment of metastases. This revised version was published online in November 2006 with corrections to the Cover Date.  相似文献   
7.
8.
Natural rubber (cis-1,4 polyisoprene) is synthesised in the milky cytoplasm, the latex, of specialized cells called laticifers in the bark tissues of the rubber tree (Hevea brasiliensis). Regeneration mechanism of latex after each tapping (controlled wounding of the bark) was studied in relation to lutoid membrane enzymes and protein synthesis in twelve rubber clones with varying yield potentials during the peak rubber yielding season. High activity of membrane enzymes and better availability of biochemical energy [ATP] were observed in clones viz; RRII 105, RRIM 600, PB 260, RRII 422 and RRII 430. The highest protein biosynthetic capacity was noticed in clone PB 260 and RRIM 600. However, high ATP content, increased invertase activity and protein biosynthesis were observed in the medium yielding clone GT1 compared to clones with low rubber yield potential. Very low sugar content and increased invertase activity in the latex of clone PB 260 indicated intense latex metabolism with high protein turnover that implies fast recouping of the cellular metabolites lost during latex harvesting. Clone PB 217 was characterized by very high sucrose and low ATP concentration and ATPase activity in latex indicating slow metabolism and hence be suitable for inducing latex metabolism using ethylene stimulant. Low rubber yielding clones such as RRII 33 and RRII 38 were consistently recorded a high sucrose content but very low activity of membrane enzymes, reduced ATP concentration and low protein biosynthesis in latex. Among the recently released modern clones (RRII 400 series), latex regeneration capacity was higher in RRII 422 and RRII 430. The significance of lutoid membrane transport and protein synthesis is discussed in relation to general latex metabolism of these rubber clones. The outcome of this study would be helpful to design suitable latex harvesting systems and yield stimulation methods for optimizing latex production in each clone based on metabolic profiling.  相似文献   
9.
Dehydroepiandrosterone (DHEA) sulfate which is present at micromolar levels in the plasma, can be desulfated to supply free DHEA for metabolism to androgens or estrogens in peripheral tissues. Human cytosolic sulfotransferase (SULT) 2A1 catalyzes DHEA sulfation in the adrenal cortex. Three SULT2A1 nonsynonymous coding single nucleotide polymorphisms (SNPs), identified only in African Americans (AA), are associated with decreased levels of activity and expression as compared to wild-type cDNA when expressed in COS cells. To test whether the SNPs are associated with decreased plasma androgens, 124 normal AA men were genotyped and plasma DHEA, DHEA-sulfate and testosterone levels determined. The two SNPs identified in these participants occurred at allelic frequencies of 0.044 (G187C) and 0.101 (G781A). The G187C SNP was highly linked to the G781A SNP. Although no differences in hormone levels were associated with the individual SNPs, a significant increase in the DHEA:DHEA-sulfate ratio was observed in participants with a heterozygous G187C/G781A genotype. Increased free DHEA levels may result in increased testosterone synthesis and stimulation in the prostate, therefore a group of AA prostate cancer (PC) patients and controls were genotyped. No significant association of the presence of the different SULT2A1 alleles with the occurrence of PC was detected.  相似文献   
10.
Kim H  Deshane J  Barnes S  Meleth S 《Life sciences》2006,78(18):2060-2065
Grape seed extract (GSE) is a commonly available dietary supplement taken for the anti-oxidant activity that's attributed to its proanthocyanidin (oligomers of monomeric polyphenols) content. Similar polyphenol-enriched preparations from blueberries and soy have shown protection against ovariectomy-induced or age-related cognitive deficits, suggesting that the molecular changes induced by these polyphenol preparations correlated with behavioral benefit. We hypothesized that ingestion of polyphenol-enriched preparations such as GSE would be manifested as protein changes that would be consistent with neuroprotection. Proteomics technology, namely 2D gel electrophoresis and mass spectrometry, identified quantitative changes in specific proteins induced in adult rat brain following ingestion of a powdered preparation of GSE. As recently reported [Deshane, J., Chaves, L., Sarikonda, K.V., Isbell, S., Wilson, L., Kirk, M., Grubbs, C., Barnes, S., Meleth, S. and Kim, H., 2004. Proteomics analysis of rat brain protein modulations by grape seed extract. Journal of Agricultural and Food Chemistry 52, 7872-7883.], the direction of change for the majority of the affected proteins was opposite to the direction the proteins were changed in either Alzheimer disease or in transgenic mouse models of dementia. A conservative conclusion is that GSE has neuroprotective activity, by affecting specific proteins in particular ways. In this chapter, elements of proteomics-type analysis are discussed that demonstrate the power of the technology to enable discovery of proteins involved in the response of the brain to a stimulus whether it be a dietary supplement, or a psychoactive drug. The fact that GSE affects proteins implicated in cognitive disorders suggests moreover that GSE may have impact on the actions of psychoactive drugs by maintaining an overall viability of the nervous system.  相似文献   
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