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991.
A pharmacophore for increasing HDLC was proposed based on common structural features of non-thio-containing compounds with HDLC enhancing properties. A search of the compound database identified various series of these non-thio-containing compounds, including a novel tricyclic imidazoisoquinolone. Preparation of 1-aryl-3-oxo-1,3-dihydro-2-benzofuran-1-carboxamides using a novel and widely applicable one-step process from 2-acyl benzoic acids is reported. Reaction of diamines with 1-aryl-3-oxo-1,3-dihydro-2-benzofuran-1-carboxamides and related aza-analogues proceeded with regio-control to furnish imidazoisoquinolones, pyrimidoisoquinolones, and imidazonaphthyridines. NMR studies and X-ray crystallography confirmed the regiochemistry of the products. Compounds of these series increased concentrations of HDLC in test animals following oral administration.  相似文献   
992.
Chen J  Shi Y  Liu W  Chai R  Fu Y  Zhuang J  Wu J 《遗传学报》2011,38(5):209-216
Rice blast, caused by Magnaporthe oryzae, is one of the most devastating diseases. Using map-based strategy and in silico approach we isolated a new rice (Oryza sativa L.) blast resistance allele of Pid3, designated Pi25, from a stable blast resistance cultivar Gumei2. Overexpression analysis and complementation test showed that Pi25 conferred blast resistance to M. oryzae isolate js001-20. Sequence analysis showed that Pi25 was an intronless gene of 2772 nucleotides with single nucleotide substitution in comparison to Pid3 at the nucleotide position 459 and predicatively encoded a typical coiled coil-nucleotide binding site-leucine rich repeat (CC--NBS--LRR) protein of 924 amino acid residuals with 100% identity to Pid3 putative protein. The susceptible allele pi25 in Nipponbare contained a nonsense mutation at the nucleotide position 2209 resulting in a truncated protein with 736 amino acid residuals. In addition, 14 nucleotide substitutions resulting in 10 amino acid substitutions were identified between Pi25 and pi25 upstream the premature stop codon in the susceptible allele. Although the mechanism of Pi25/Pid3-mediated resistance needs to be further investigated, the isolation of the allele would facilitate the utilization of Pi25/Pid3 in rice blast resistance breeding program via transgenic approach and marker assisted selection.  相似文献   
993.

Background

We examined the relationship between morale measured by the Philadelphia Geriatric Morale Scale (PGC) and disability, social support, religiosity, and personality traits. Instruments predicting morale were then tested against PGC domains.

Methods

The study utilized a cross-sectional survey with a multistage cluster sampling design. Instruments used were disability (disease burden; WHO Disability Score-II, WHODAS-II), social support (Duke Social Support Scale, DUSOCS; Lubben Social Network Scale, LSNS-6; Medical Outcomes Study Social Support Survey, MOS-SSS), religiosity (Revised Intrinsic-Extrinsic Religious Orientation Scale, I/E-R), and personality (Ten-Item Personality Inventory, TIPI). These were plotted as bar charts against PGC, resolved with one-way ANOVA and Kruskal-Wallis tests, then corrected for multiple comparisons. This process was repeated with PGC domains. Contribution of factors was modeled using population attributable risk (PAR) and odds ratios. Effect of confounders such as gender, age, and ethnicity were checked using binary logistic regression.

Results

All instruments showed clear relationships with PGC, with WHODAS-II and DUSOCS performing well (ANOVA p<0.001). For PGC domains, attitude toward aging and lonely dissatisfaction trended together, while agitation did not. PAR, odds ratios, and Exp(β) were disability (WHODAS-II: 28.5%, 3.8, 2.8), social support (DUSOCS: 28.0%, 3.4, 2.2), religiosity (I/E-R: 21.6%, 3.2, 2.1), and personality (TIPI: 27.9%, 3.6, 2.4). Combined PAR was 70.9%.

Conclusions

Disability, social support, religiosity, and personality strongly influence morale in the elderly. WHODAS-II and DUSOCS perform best in measuring disability and social support respectively.  相似文献   
994.
Chew KC  Matsuda N  Saisho K  Lim GG  Chai C  Tan HM  Tanaka K  Lim KL 《PloS one》2011,6(5):e19720

Background

Mutations in the parkin gene, which encodes a ubiquitin ligase (E3), are a major cause of autosomal recessive parkinsonism. Although parkin-mediated ubiquitination was initially linked to protein degradation, accumulating evidence suggests that the enzyme is capable of catalyzing multiple forms of ubiquitin modifications including monoubiquitination, K48- and K63-linked polyubiquitination. In this study, we sought to understand how a single enzyme could exhibit such multifunctional catalytic properties.

Methods and Findings

By means of in vitro ubiquitination assays coupled with mass spectrometry analysis, we were surprised to find that parkin is apparently capable of mediating E2-independent protein ubiquitination in vitro, an unprecedented activity exhibited by an E3 member. Interestingly, whereas full length parkin catalyzes solely monoubiquitination regardless of the presence or absence of E2, a truncated parkin mutant containing only the catalytic moiety supports both E2-independent and E2-dependent assembly of ubiquitin chains.

Conclusions

Our results here suggest a complex regulation of parkin''s activity and may help to explain how a single enzyme like parkin could mediate diverse forms of ubiquitination.  相似文献   
995.
Novel snowflake-like Pt-Pd bimetallic nanoclusters (Pt-PdBNC) were synthesized on a screen-printed gold nanofilm electrode (SPGFE) substrate by electrochemically reducing precursors with a new constant potential/multi-potential step deposition strategy. The electrocatalytic behavior of the modified electrode (SPGFE/Pt-PdBNC) towards H(2)O(2) was investigated. The results indicate that the as-prepared Pt-PdBNC significantly enhances the electrochemical reduction of H(2)O(2) in neutral media, exhibiting preferable electrocatalytic performance compared to Pt and Pd monometallic nanoclusters. Under optimum conditions, SPGFE/Pt-PdBNC offers linear responses for H(2)O(2) in the concentration range from 0.005 to 6 mM with an ultrahigh sensitivity of 804 mA M(-1) cm(-2) and excellent selectivity. Furthermore, glucose oxidase was immobilized on the Pt-PdBNC structure, and the fabricated biosensor presents favorable properties for glucose sensing.  相似文献   
996.
Structural modification of a series of dual LXRα/β agonists led to the identification of a new class of LXRβ partial agonists. An X-ray co-crystal structure shows that a representative member of this series, pyrrole 5, binds to LXRβ with a reversed orientation compared to 1.  相似文献   
997.
Chai XJ  Jacobs LF 《PloS one》2012,7(2):e32816
The relative length of the second-to-fourth digits (2D:4D) has been linked with prenatal androgen in humans. The 2D:4D is sexually dimorphic, with lower values in males than females, and appears to correlate with diverse measures of behavior. However, the relationship between digit ratio and cognition, and spatial cognition in particular, has produced mixed results. In the present study, we hypothesized that spatial tasks separating cue conditions that either favored female or male strategies would examine this structure-function correlation with greater precision. Previous work suggests that males are better in the use of directional cues than females. In the present study, participants learned a target location in a virtual landscape environment, in conditions that contained either all directional (i.e., distant or compass bearing) cues, or all positional (i.e., local, small objects) cues. After a short delay, participants navigated back to the target location from a novel starting location. Males had higher accuracy in initial search direction than females in environments with all directional cues. Lower digit ratio was correlated with higher accuracy of initial search direction in females in environments with all directional cues. Mental rotation scores did not correlate with digit ratio in either males or females. These results demonstrate for the first time that a sex difference in the use of directional cues, i.e., the sense of direction, is associated with more male-like digit ratio.  相似文献   
998.
999.
1000.
Transfusion-related acute lung injury (TRALI) is a leading cause of transfusion-associated mortality that can occur with any type of transfusion and is thought to be primarily due to donor antibodies activating pulmonary neutrophils in recipients. Recently, a large prospective case controlled clinical study of cardiac surgery patients demonstrated that despite implementation of male donors, a high incidence of TRALI still occurred and suggested a need for additional interventions in susceptible patient populations. To examine if intravenous immunoglobulin (IVIg) may be effective, a murine model of antibody-mediated acute lung injury that approximates human TRALI was examined. When BALB/c mice were injected with the anti-major histocompatibility complex class I antibody 34-1-2s, mild shock (reduced rectal temperature) and respiratory distress (dyspnea) were observed and pre-treatment of the mice with 2 g/kg IVIg completely prevented these symptoms. To determine IVIg's usefulness to affect severe lung damage, SCID mice, previously shown to be hypersensitive to 34-1-2s were used. SCID mice treated with 34-1-2s underwent severe shock, lung damage (increased wet/dry ratios) and 40% mortality within 2 hours. Treatment with 2 g/kg IVIg 18 hours before 34-1-2s administration completely protected the mice from all adverse events. Treatment with IVIg after symptoms began also reduced lung damage and mortality. While the prophylactic IVIg administration did not affect 34-1-2s-induced pulmonary neutrophil accumulation, bone marrow-derived neutrophils from the IVIg-treated mice displayed no spontaneous ROS production nor could they be stimulated in vitro with fMLP or 34-1-2s. These results suggest that IVIg prevents murine antibody-mediated acute lung injury at the level of neutrophil ROS production and thus, alleviating tissue damage.  相似文献   
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