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21.
In most countries Cannabis is the most widely used illegal drug. Its use during pregnancy in developed nations is estimated to be approximately 10%. Recent evidence suggests that the endogenous cannabinoid system, now consisting of two receptors and multiple endocannabinoid ligands, may also play an important role in the maintenance and regulation of early pregnancy and fertility. The purpose of this review is therefore twofold, to examine the impact that cannabis use may have on fertility and reproduction, and to review the potential role of the endocannabinoid system in hormonal regulation, embryo implantation and maintenance of pregnancy.  相似文献   
22.
Although the lipid-based method for coating of magnetic nanoparticles (MNPs) is rapid and simple, the unstable state of the lipid layer is a major limitation for the practical application of this method. We devised a method to prepare stabilized MNPs by covalent modifications such as lipid polymerization and anchoring of the lipid layer. The stability of the modified lipid layer was demonstrated by the stable status of enzymes immobilized on the MNPs and the resistance of the MNPs to aggregation. We also determined the maximum ratio of nonpolymerizable lipophilic compounds that can be included in the layer without significantly reducing stability.  相似文献   
23.
Choi B  Kang J  Park YS  Lee J  Cho NJ 《Molecules and cells》2011,31(5):455-459
FRM-1 is a member of the FERM protein superfamily containing a FERM domain, which is a highly conserved protein-protein interaction module found in most eukaryotes. Although FRM-1 is thought to be involved in linking intracellular proteins to membrane proteins, the specific role for FRM-1 remains to be elucidated. In an effort to explore the biological function of FRM-1, we examined the phenotype of frm-1(tm4168) mutant worms. We observed that frm-1(tm4168) worms have a delayed hatching phenotype. Twelve hours after being laid, when virtually all wild-type eggs had hatched, only 64% of frm-1(tm4168) eggs had hatched. About 3% of frm-1(tm4168) eggs failed to hatch, even 3 days after they had been laid. We also found that frm-1(tm4168) mutants displayed a temperature-sensitive sterility phenotype. About 13% of frm-1(tm4168) worms were unable to produce eggs or produced nonviable eggs at 25°C. In contrast, less than 1% of wild-type animals were sterile at this temperature. At 20°C, neither the mutant nor wild type appeared to be sterile. Western blot analysis indicates that FRM-1 is expressed throughout the developmental stages with the strongest expression at the egg stage. Immunostaining experiments revealed that FRM-1 is mainly localized to the plasma membrane of most if not all cells at an early embryonic stage and to the plasma membrane of P cells during the late embryonic stages. GFP fusion experiments showed that FRM-1 can be expressed in the pharynx and intestine at the larval and adult stages. Our data suggest that FRM-1 may participate in diverse biological processes, including embryonic development.  相似文献   
24.
Lee  Yoonjae  Seo  Youngran  Lee  Boram  Kwon  Hyuenyoung  Chung  Kyungsu  Kim  Young Gyu 《Amino acids》2022,54(12):1601-1610
Amino Acids - A divergent synthetic strategy starting from a common trans-oxazolidine dicarboxylate intermediate has been successful to produce several non-proteinogenic...  相似文献   
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26.
Bacillus sp. strain YU-1006, which was isolated from soil, produced a bacteriolytic enzyme which was active against Streptococcus mutans KCTC 3283. The enzyme was purified 60 fold with a 6% yield by CM-cellulose column chromatography and CM-Sephadex G-50 column chromatography. Lytic activity was stable in the range of pH 6.0~9.0 up to 42°e active enzyme is a 24,000 dalton monomer as estimated by SDS-PAGE.  相似文献   
27.
Macrophage inflammatory protein-3α (MIP-3α) and its sole receptor, CCR6, play pivotal roles in neuroinflammatory processes induced by brain ischemic insults. In this study, we investigated transient ischemia-induced changes in MIP-3α and CCR6 protein expressions in the hippocampal CA1 area following 5 min of transient global cerebral ischemia (tgCI) in gerbils. Both MIP-3α and CCR6 immunoreactivities were very strongly expressed in pyramidal neurons of the CA1 area from 6 h to 1 day after tgCI and were hardly shown 4 days after tgCI. In addition, strong MIP-3α immunoreactivity was newly expressed in astrocytes 6 h after tgCI. These results indicate that tgCI causes apparent changes in MIP-3α and CCR6 expressions in pyramidal neurons and astrocytes in the hippocampal CA1 area and suggest that tgCI-induced changes in MIP-3α and CCR6 expressions might be closely associated with neuroinflammatory processes in brain ischemic regions.  相似文献   
28.
We aimed to identify tissue biomarkers that predict early biochemical recurrence (BCR) in patients with high-risk prostate cancer (PC), toward the goal of increasing the benefits of neoadjuvant hormonal therapy (NHT). In 2005–2012, prostatectomy specimens were collected from 134 PC patients who had received NHT and radical prostatectomy. The expression of 13 tissue biomarkers was assessed in the specimens via immunohistochemistry. Time to BCR and factors predictive of BCR were determined by using the Cox proportional hazards model. During the follow-up period (median, 57.5 months), 67 (50.0%) patients experienced BCR. Four (3.0%) patients were tumor-free in the final pathology assessment, and 101 (75.4%) had negative resection margins. Prostate stem cell antigen (PSCA) was the only significant prognostic tissue biomarker of BCR [hazard ratio (HR), 2.58; 95% confidence interval (CI), 1.06–6.27; p = 0.037] in a multivariable analysis adjusted by the clinicopathological variables that also significantly predicted BCR; these were seminal vesicle invasion (HR, 2.39; 95% CI, 1.32–4.34), initial prostate serum antigen level (HR 1.01; 95% CI, 1.001–1.020), prostate size (HR, 0.93; 95% CI, 0.90–0.97), and the Gleason score of preoperative biopsies (HR, 1.34; 95% CI, 1.01–1.79). We suggest that PSCA is a useful tissue marker for predicting BCR in patients with high risk PC receiving NHT and radical prostatectomy.  相似文献   
29.
Bacterial ribonuclease III (RNase III) belongs to the RNase III enzyme family, which plays a pivotal role in controlling mRNA stability and RNA processing in both prokaryotes and eukaryotes. In the Vibrio vulnificus genome, one open reading frame encodes a protein homologous to E. coli RNase III, designated Vv-RNase III, which has 77.9 % amino acid identity to E. coli RNase III. Here, we report that Vv-RNase III has the same cleavage specificity as E. coli RNase III in vivo and in vitro. Expressing Vv-RNase III in E. coli cells deleted for the RNase III gene (rnc) restored normal rRNA processing and, consequently, growth rates of these cells comparable to wild-type cells. In vitro cleavage assays further showed that Vv-RNase III has the same cleavage activity and specificity as E. coli RNase III on RNase III-targeted sequences of corA and mltD mRNA. Our findings suggest that RNase III-like proteins have conserved cleavage specificity across bacterial species.  相似文献   
30.
Aim: To develop antibody–aptamer functionalized fibre‐optic biosensor for specific detection of Listeria monocytogenes from food products. Methods and Results: Aptamer, a single‐stranded oligonucleotide ligand that displays affinity for the target molecule, was used in the assay to provide sensor specificity. Aptamer‐A8, specific for internalin A, an invasin protein of L. monocytogenes, was used in the fibre‐optic sensor together with antibody in a sandwich format for detection of L. monocytogenes from food. Biotinylated polyclonal anti‐Listeria antibody, P66, was immobilized on streptavidin‐coated optical waveguide surface for capturing bacteria, and Alexa Fluor 647‐conjugated A8 was used as a reporter. The biosensor was able to selectively detect pathogenic Listeria in pure culture and in mixture with other bacteria at a concentration of approx. 103 CFU ml?1. This sensor also successfully detected L. monocytogenes cells from artificially contaminated (initial inoculation of 102 CFU 25 g?1) ready‐to‐eat meat products such as sliced beef, chicken and turkey after 18 h of enrichment. Conclusion: Based on the data presented in this study, the antibody–aptamer functionalized fibre‐optic biosensor could be used as a detection tool for sensitive and specific detection of L. monocytogenes from foods. Significance and Impact of the Study: The study demonstrates feasibility and novel application of aptamer on fibre‐optic biosensor platform for the sensitive detection of L. monocytogenes from food products.  相似文献   
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