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61.
Journal of Plant Biochemistry and Biotechnology - A glycosylated heat stable trypsin chymotrypsin inhibitor was isolated from Cyamopsis tetragonoloba seeds. It is being reported for the first time...  相似文献   
62.
BackgroundApproximately 8% of the human genome consists of sequences of retroviral origin, a result of ancestral infections of the germ line over millions of years of evolution. The most recent of these infections is attributed to members of the human endogenous retrovirus type-K (HERV-K) (HML-2) family. We recently reported that a previously undetected, large group of HERV-K (HML-2) proviruses, which are descendants of the ancestral K111 infection, are spread throughout human centromeres.ResultsStudying the genomes of certain cell lines and the DNA of healthy individuals that seemingly lack K111, we discover new HERV-K (HML-2) members hidden in pericentromeres of several human chromosomes. All are related through a common ancestor, termed K222, which is a virus that infected the germ line approximately 25 million years ago. K222 exists as a single copy in the genomes of baboons and high order primates, but not New World monkeys, suggesting that progenitor K222 infected the primate germ line after the split between New and Old World monkeys. K222 exists in modern humans at multiple loci spread across the pericentromeres of nine chromosomes, indicating it was amplified during the evolution of modern humans.ConclusionsCopying of K222 may have occurred through recombination of the pericentromeres of different chromosomes during human evolution. Evidence of recombination between K111 and K222 suggests that these retroviral sequences have been templates for frequent cross-over events during the process of centromere recombination in humans.  相似文献   
63.
16-Dehydropregnenolone undergoes a smooth annulation with propan-1-amine and aromatic aldehydes. Several amine derivatives of 16- dehydropregnenolone were synthesized and evaluated as inhibitors of DPP-IV. The structures of compounds were confirmed by 1H, 13C, NMR and mass spectral analysis. Among 17 compounds evaluated only five compounds 1, 9, 13, 15 and 16 demonstrated significant inhibition of DPP. This study suggest that introduction of appropriate substituents in the 16-dehydropregnenolone plays an important role in DPP-IV inhibitory activity.  相似文献   
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65.
Progesterone receptor (PR) is strongly associated with disease prognosis and therapeutic efficacy in hormone-related diseases such as endometriosis and breast, ovarian, and uterine cancers. Receptor status is currently determined by immunohistochemistry assays. However, noninvasive PR imaging agents could improve disease detection and help elucidate pathological molecular pathways, leading to new therapies and animal disease models. A series of water-soluble PR-targeted magnetic resonance imaging (MRI) probes were synthesized using Cu(I)-catalyzed click chemistry and evaluated in vitro and in vivo. These agents demonstrated activation of PR in vitro and preferential accumulation in PR(+) compared to PR(-) human breast cancer cells with low toxicity. In xenograft tumor models, the agents demonstrated enhanced signal intensity in PR(+) tumors compared to PR(-) tumors. The results suggest that these agents may be promising MRI probes for PR(+) diseases.  相似文献   
66.
Maternal nutrition is an important determinant of one-carbon metabolism that lies at the heart of intrauterine epigenetic programming. Exchange of nutrients and other vital molecules between the mother and fetus takes place across the placenta and hence may play direct role in fetal programming. Pre-eclampsia (PE) originates in the placenta and altered maternal nutrition may influence epigenetic patterns in the placenta, thereby affecting birth outcome. In the present study, we investigated the global DNA methylation levels in placentas of pre-eclampsia women (i.e., women delivering at term and those delivering preterm) and studied their associations with maternal blood pressure and birth outcome. Increased homocysteine and global DNA methylation levels were seen in the pre-eclampsia group (term and preterm PE) when compared with the normotensive group (p?相似文献   
67.
Potential adverse effects of excess maternal folic acid supplementation on a vegetarian population deficient in vitamin B(12) are poorly understood. We have previously shown in a rat model that maternal folic acid supplementation at marginal protein levels reduces brain omega-3 fatty acid levels in the adult offspring. We have also reported that reduced docosahexaenoic acid (DHA) levels may result in diversion of methyl groups towards DNA in the one carbon metabolic pathway ultimately resulting in DNA methylation. This study was designed to examine the effect of normal and excess folic acid in the absence and presence of vitamin B(12) deficiency on global methylation patterns in the placenta. Further, the effect of maternal omega 3 fatty acid supplementation on the above vitamin B(12) deficient diets was also examined. Our results suggest maternal folic acid supplementation in the absence of vitamin B(12) lowers plasma and placental DHA levels (p<0.05) and reduces global DNA methylation levels (p<0.05). When this group was supplemented with omega 3 fatty acids there was an increase in placental DHA levels and subsequently DNA methylation levels revert back to the levels of the control group. Our results suggest for the first time that DHA plays an important role in one carbon metabolism thereby influencing global DNA methylation in the placenta.  相似文献   
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69.

Background

High-dose benzodiazepine (BZD) dependence is associated with a wide variety of negative health consequences. Affected individuals are reported to suffer from severe mental disorders and are often unable to achieve long-term abstinence via recommended discontinuation strategies. Although it is increasingly understood that treatment interventions should take subjective experiences and beliefs into account, the perceptions of this group of individuals remain under-investigated.

Methods

We conducted an exploratory qualitative study with 41 adult subjects meeting criteria for (high-dose) BZD-dependence, as defined by ICD-10. One-on-one in-depth interviews allowed for an exploration of this group’s views on the reasons behind their initial and then continued use of BZDs, as well as their procurement strategies. Mayring’s qualitative content analysis was used to evaluate our data.

Results

In this sample, all participants had developed explanatory models for why they began using BZDs. We identified a multitude of reasons that we grouped into four broad categories, as explaining continued BZD use: (1) to cope with symptoms of psychological distress or mental disorder other than substance use, (2) to manage symptoms of physical or psychological discomfort associated with somatic disorder, (3) to alleviate symptoms of substance-related disorders, and (4) for recreational purposes, that is, sensation-seeking and other social reasons. Subjects often considered BZDs less dangerous than other substances and associated their use more often with harm reduction than as recreational. Specific obtainment strategies varied widely: the majority of participants oscillated between legal and illegal methods, often relying on the black market when faced with treatment termination.

Conclusions

Irrespective of comorbidity, participants expressed a clear preference for medically related explanatory models for their BZD use. We therefore suggest that clinicians consider patients’ motives for long-term, high-dose BZD use when formulating treatment plans for this patient group, especially since it is known that individuals are more compliant with approaches they perceive to be manageable, tolerable, and effective.  相似文献   
70.

Objective

To determine the prevalence of cataract surgery and factors associated with post-surgical visual outcomes in migrant Indians living in Singapore.

Research Design and Methods

We conducted a population-based study in 3,400 Indian immigrants residing in Singapore−the Singapore Indian Eye Study (SINDI). All participants underwent comprehensive medical eye examination and a standardized interview. Post-operative visual impairment (VI) was defined as best-corrected or presenting visual acuity (BCVA or PVA) of 20/60 or worse.

Results

The age- and gender-standardized prevalence of cataract surgery was 9.7% (95% confidence interval [CI]: 8.9%, 10.7%) in Singapore resident Indians. Post-operative VI defined by BCVA occurred in 10.9% eyes (87/795). The main causes of post-operative VI were diabetic retinopathy (20.7%), posterior capsular opacification (18.4%), and age-related macular degeneration (12.6%). Undercorrected refractive error doubled the prevalence of post-operative VI when PVA was used.

Conclusions

The rate of cataract surgery is about 10% in Indian residents in Singapore. Socioeconomic variables and migration had no significant impact on the prevalence of cataract surgery. Diabetic retinopathy was a major cause of post-operative VI in migrant Indians living in Singapore. Uncorrected postoperative refractive error remains an efficient way to improve vision.  相似文献   
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