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11.
Triglyceride deposit cardiomyovasculopathy (TGCV) is a rare and newly identified disease among patients requiring cardiac transplantation. TGCV is characterized by cardiomyocyte steatosis and triglyceride (TG)-deposit atherosclerosis, resulting from the abnormal intracellular metabolism of TG. TGCV is classified into primary and idiopathic types. Primary TGCV carries ultra-rare genetic mutations in the adipose triglyceride lipase (ATGL), a rate-liming enzyme that hydrolyzes intracellular TG in adipose and non-adipose tissues. Idiopathic TGCV, first identified among autopsied individuals with diabetes mellitus (DM) with severe heart diseases, shows no ATGL mutations and its causes and underlying mechanisms are still unknown. TGCV is difficult to diagnose in daily clinics, thereby demanding feasible diagnostic procedures. We aimed to develop an assay to measure ATGL activity using peripheral leucocytes. Human his6-ATGL was expressed in COS1 cells, purified to homogeneity, and used to raise a polyclonal antibody neutralizing TG-hydrolyzing activity of ATGL. We developed a selective immunoinactivation assay (SIIA) for the quantitation of ATGL activity in cell lysates of leucocytes by the antibody neutralizing ATGL activities. ATGL activity was measured in 13 idiopathic TGCV patients, with two patients with primary TGCV as the negative control. Healthy (non-DM) and DM controls without heart diseases were also subjected. The developed SIIA assay revealed significant reduction in ATGL activity in leucocytes from patients with idiopathic TGCV who did not carry ATGL mutations as compared with non-DM and DM controls. Thus, ATGL in leucocytes may be an important biomarker for the diagnosis of TGCV and our assay may provide insights into pathophysiology and elucidate the underlying mechanism of TGCV and related disorders.  相似文献   
12.
This paper deals with smart bimolecular recognition for instantaneous determination. In particular, we installed the fluorescence resonance energy transfer (FRET) system in phosphorylcholine (PC) group enriched nanoparticles (NPs). The most favorable characteristics were as follows: (i) the suppression of nonspecific protein adsorption by the PC group enriched surface and (ii) simple bioassay protocol relative to the conventional enzyme-linked immunosorbent assay (ELISA). In the case of immunoassays, nonspecific interaction and complex protocols are known dominant problems. To address these issues, we designed FRET-installed NPs. Agglutination of NPs is a fundamental immunoassay technique; however, it is not quantitative. By evaluating the degree of agglutination based on the fluorescence intensity, the resulting information can be used for diagnosis. Therefore, we installed the FRET system on the surface of the NPs. In this paper, C-reactive protein (CRP) and osteopontin (OPN) were the target biomarkers for instantaneous determination, and the resulting fluorescence intensity correlated well with changes in the concentrations of the target molecules. The immunoassay protocol was quite simple, involving only the mixing of FRET-installed NPs and target molecules, such as CRP and OPN antigens. We successfully evaluated the concentration of the target biomarkers, even when human serum albumin was present as an interference molecule.  相似文献   
13.

Key message

Thirty significant associations between 22 SNPs and five plant architecture component traits in Chinese upland cotton were identified via GWAS. Four peak SNP loci located on chromosome D03 were simultaneously associated with more plant architecture component traits. A candidate gene, Gh_D03G0922, might be responsible for plant height in upland cotton.

Abstract

A compact plant architecture is increasingly required for mechanized harvesting processes in China. Therefore, cotton plant architecture is an important trait, and its components, such as plant height, fruit branch length and fruit branch angle, affect the suitability of a cultivar for mechanized harvesting. To determine the genetic basis of cotton plant architecture, a genome-wide association study (GWAS) was performed using a panel composed of 355 accessions and 93,250 single nucleotide polymorphisms (SNPs) identified using the specific-locus amplified fragment sequencing method. Thirty significant associations between 22 SNPs and five plant architecture component traits were identified via GWAS. Most importantly, four peak SNP loci located on chromosome D03 were simultaneously associated with more plant architecture component traits, and these SNPs were harbored in one linkage disequilibrium block. Furthermore, 21 candidate genes for plant architecture were predicted in a 0.95-Mb region including the four peak SNPs. One of these genes (Gh_D03G0922) was near the significant SNP D03_31584163 (8.40 kb), and its Arabidopsis homologs contain MADS-box domains that might be involved in plant growth and development. qRT-PCR showed that the expression of Gh_D03G0922 was upregulated in the apical buds and young leaves of the short and compact cotton varieties, and virus-induced gene silencing (VIGS) proved that the silenced plants exhibited increased PH. These results indicate that Gh_D03G0922 is likely the candidate gene for PH in cotton. The genetic variations and candidate genes identified in this study lay a foundation for cultivating moderately short and compact varieties in future Chinese cotton-breeding programs.
  相似文献   
14.
ABSTRACT: BACKGROUND: We recently reported that short-term treatment with liraglutide (20.0 +/- 6.4 days) reduced body weight and improved some scales of eating behavior in Japanese type 2 diabetes inpatients. However, it remained uncertain whether such liraglutide-induced improvement is maintained after discharge from the hospital. The aim of the present study was to determine the long-term effects of liraglutide on body weight, glycemic control, and eating behavior in Japanese obese type 2 diabetics. METHODS: Patients with obesity (body mass index (BMI) >25 kg/m2) and type 2 diabetes were hospitalized at Osaka University Hospital between November 2010 and December 2011. BMI and glycated hemoglobin (HbA1c) were examined on admission, at discharge and at 1, 3, and 6 months after discharge. For the liraglutide group (BMI; 31.3 +/- 5.3 kg/m2, n = 29), patients were introduced to liraglutide after correction of hyperglycemic by insulin or oral glucose-lowering drugs and maintained on liraglutide after discharge. Eating behavior was assessed in patients treated with liraglutide using The Guideline For Obesity questionnaire issued by the Japan Society for the Study of Obesity, at admission, discharge, 3 and 6 months after discharge. For the insulin group (BMI; 29.1 +/- 3.0 kg/m2, n = 28), each patient was treated with insulin during hospitalization and glycemic control maintained by insulin after discharge. RESULTS: Liraglutide induced significant and persistent weight loss from admission up to 6 months after discharge, while no change in body weight after discharge was noted in the insulin group. Liraglutide produced significant improvements in all major scores of eating behavior questionnaire items and such effect was maintained at 6 months after discharge. Weight loss correlated significantly with the decrease in scores for recognition of weight and constitution, sense of hunger, and eating style. CONCLUSION: Liraglutide produced meaningful long-term weight loss and significantly improved eating behavior in obese Japanese patients with type 2 diabetes.  相似文献   
15.
An exhaustive search of the crystal structure of beta-chitin was carried out by simultaneously optimizing all the structural parameters based on published X-ray diffraction data and stereochemical criteria. The most probable structure was characterized by a parallel-up chain polarity, a gg orientation of hydroxymethyl groups and an intermolecular hydrogen bond along the a-axis, which essentially reproduced the original structure proposed by Gardner and Blackwell. The proposed crystal structure was subsequently subjected to crystal modeling using the AMBER force field. The probable orientation of hydroxyl groups and their motional behaviors is proposed based on calculations for the crystal models identified. Solvated crystal models exhibited a slightly deformed structure with the formation of appreciable numbers of hydrogen bonds along the b-axis.  相似文献   
16.
Nesidiocoris tenuis, an omnivorous arthropod, infests plants in either the absence or presence of prey arthropods. We studied whether plant-infestation experience of N. tenuis affected its subsequent prey-finding behavior. We used sesame plants and eggplants as food plants for N. tenuis, and common cutworm (CCW) (Spodoptera litura larvae) as prey. We focused on their olfactory response to CCW-infested sesame plants versus CCW-infested eggplants in a Y-tube olfactometer. When N. tenuis adults experienced the infestation of sesame plants for one day, they preferred volatiles from CCW-infested sesame plants to those from CCW-infested eggplants. By contrast, when N. tenuis experienced the infestation of eggplants for one day, they showed no difference in their preference between the two odor sources. When the duration of the infestation of plants was increased to four days, N. tenuis that had experienced sesame plants showed a reversed response: they preferred CCW-infested eggplant volatiles, while those that had infested eggplants again showed no difference in their preference. Next, we studied the olfactory preference of N. tenuis that had previously infested plants with moth (Ephestia kuehniella) eggs. We found that irrespective of plant species and of duration of experience (either one or four days), N. tenuis adults that had previously experienced one plant species showed a significant preference for volatiles from CCW-infested plants of the same species. The blends of the volatiles emitted from CCW-infested sesame plants and those from CCW-infested eggplants were qualitatively different. Possibility to control the olfactory response of N. tenuis to certain prey-infested plant volatiles by adjusting their feeding history is discussed.  相似文献   
17.
Carbamazepine (CBZ) is one of the most commonly prescribed antiepileptic drugs (AEDs). However, a higher rate of congenital anomalies has been found in infants of mothers treated with CBZ during early pregnancy. Here, we characterize the effects of CBZ using a mouse ES cell differentiation system. The analysis of tissue-specific gene markers showed that CBZ induced early endodermal and mesodermal differentiation but inhibited differentiation of later stages. CBZ also induced ectodermal development, and there was evidence of neural differentiation as ES cells with an immature neuronal phenotype were observed. In contrast, valproic acid (VPA), another anticonvulsant drug, was previously shown to be able to induce ES cells to differentiate into neurons with a mature appearance. CBZ was less cytotoxic to ES cells than VPA. The in vitro ES cell assay system has the potential to provide a rapid and accurate approach for estimating the in vivo embryotoxicity of therapeutic drugs.  相似文献   
18.
Ascochlorin, a non-toxic prenylphenol compound derived from the fungus Ascochyta viciae, has been shown recently to have anti-cancer effects on various human cancer cells. However, the precise molecular mechanism of this anti-cancer activity remains to be elucidated. Here, we investigated the effects of ascochlorin on hypoxia-inducible factor-1α (HIF-1α) and vascular endothelial growth factor (VEGF) expression in human epidermoid cervical carcinoma CaSki cells. Ascochlorin inhibited epidermal growth factor (EGF)-induced HIF-1α and VEGF expression through multiple potential mechanisms. First, ascochlorin selectively inhibited HIF-1α expression in response to EGF stimulation, but not in response to hypoxia (1% O(2)) or treatment with a transition metal (CoCl(2)). Second, ascochlorin inhibited EGF-induced ERK-1/2 activation but not AKT activation, both of which play essential roles in EGF-induced HIF-1α protein synthesis. Targeted inhibition of epidermal growth factor receptor (EGFR) expression using an EGFR-specific small interfering RNA (siRNA) diminished HIF-1α expression, which suggested that ascochlorin inhibits HIF-1α expression through suppression of EGFR activation. Finally, we showed that ascochlorin functionally abrogates in vivo tumor angiogenesis induced by EGF in a Matrigel plug assay. Our data suggest that ascochlorin inhibits EGF-mediated induction of HIF-1α expression in CaSki cells, providing a potentially new avenue of development of anti-cancer drugs that target tumor angiogenesis.  相似文献   
19.
The mechanism of neurite growth is complicated, involving continuous cytoskeletal rearrangement and vesicular trafficking. Cytohesin-2 is a guanine nucleotide exchange factor for Arf6, an Arf family molecular switch protein, controlling cell morphological changes such as neuritogenesis. Here, we show that cytohesin-2 binds to a protein with a previously unknown function, CCDC120, which contains three coiled-coil domains, and is transported along neurites in differentiating N1E-115 cells. Transfection of the small interfering RNA (siRNA) specific for CCDC120 into cells inhibits neurite growth and Arf6 activation. When neurites start to extend, vesicles containing CCDC120 and cytohesin-2 are transported in an anterograde manner rather than a retrograde one. As neurites continue extension, anterograde vesicle transport decreases. CCDC120 knockdown inhibits cytohesin-2 localization into vesicles containing CCDC120 and diffuses cytohesin-2 in cytoplasmic regions, illustrating that CCDC120 determines cytohesin-2 localization in growing neurites. Reintroduction of the wild type CCDC120 construct into cells transfected with CCDC120 siRNA reverses blunted neurite growth and Arf6 activity, whereas the cytohesin-2-binding CC1 region-deficient CCDC120 construct does not. Thus, cytohesin-2 is transported along neurites by vesicles containing CCDC120, and it mediates neurite growth. These results suggest a mechanism by which guanine nucleotide exchange factor for Arf6 is transported to mediate neurite growth.  相似文献   
20.
Omentin is a recently identified adipocytokine with insulin-sensitizing effect. While lack of omentin may be related to the pathogenesis of obesity-related cardiovascular diseases, its effect in vasculature is largely unknown. We examined effects of omentin on vascular endothelial inflammatory states. Western blotting was performed to analyze inflammatory signal transduction in cultured vascular endothelia cells. The cyclic guanosine monophosphate (cGMP) content was measured using enzyme immunoassay. Treatment of human umbilical vein endothelial cells with omentin (300 ng/ml, 20 min) induced phosphorylation of 5′-AMP-activated protein kinase (AMPK) (Thr 172) and endothelial nitric oxide (NO) synthase (eNOS) (Ser 1177). Consistently, omentin increased the cGMP level. Pretreatment with omentin (300 ng/ml, 30 min) significantly inhibited the phosphorylation of JNK as well as expression of cyclooxygenase (COX)-2 by TNF-α (5 ng/ml, 20 min–24 h). An inhibitor of JNK significantly inhibited the TNF-α-induced COX-2 expression. Inhibitory effect of omentin on TNF-α-induced COX-2 was reversed by a NOS inhibitor. The present results demonstrate for the first time that omentin plays an anti-inflammatory role by preventing the TNF-α-induced COX-2 expression in vascular endothelial cells. Omentin inhibits COX-2 induction via preventing the JNK activation presumably through activation of AMPK/eNOS/NO pathways.  相似文献   
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