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181.
All-trans retinoic acid (RA) and its geometrical isomers, such as 9-cis RA, 13-cis RA, and 9,13-di-cis RA, strongly inhibited both growth and fusion of L6 myoblasts. However, illumination of white light diminished their inhibitory activity on membrane fusion with little effect on cell growth. During myogenic differentiation, the intracellular level of cAMP decreased whereas the total activity of protein kinase A as well as the protein level of its regulatory subunit I (RI) and catalytic subunit (C) increased. RAs raised the intracellular level of cAMP by over 3-fold, but decreased the total activity of protein kinase A. Like RAs, dibutyryl-cAMP inhibited myoblast fusion and reduced the expression of both RI and C subunits. These results suggest that RAs negatively modulate the differentiation of L6 myoblasts by increasing the intracellular level of cAMP, which may in turn down-regulate the expression of protein kinase A and hence its activity.  相似文献   
182.
Myeong H  Jeoung D  Kim H  Ha JH  Lee Y  Kim KH  Park C  Kaang BK 《Gene》2000,257(1):99-107
Dopamine D2 receptor (DRD2) is one of the five dopamine receptors with seven transmembrane domains that are coupled to the G protein. We have cloned and characterized the genomic and cDNA sequences of the canine DRD2 gene, which are 12.7 and 2.7 kb in size, respectively. The genomic DNA is composed of seven exons and six introns, encoding a 443 amino acid protein with 95% amino acid identity to other mammalian D2 receptors. A length polymorphism was detected in intron 3 of the receptor gene. We also characterized alternatively spliced forms of DRD2 cDNAs, DRD2L and DRD2S. They showed a higher level of expression in midbrain and thalamus. The ratio between the long and short form is similar in RT-PCR reaction. In human and rodent, the same two spliced forms are known to be coupled to G(i)-type heterotrimeric GTP binding protein, thereby opening an inwardly rectifying potassium channel, GIRK1. When the canine DRD2L and DRD2S were heterologously expressed in Xenopus oocytes, both forms activated GIRK1 potassium channels through coupling with G(i) protein. This activation was dose-dependent, demonstrating its ligand specificity.  相似文献   
183.
Ha XQ  Guo SH  Wu ZZ 《生理科学进展》2000,31(4):325-327
肝细胞生长因子是目前已知生物活性最广泛的生长因子之一,能刺激多种上皮和内皮细胞进行有丝分裂、运动以及促进肾小管形态发生,在组织器官损伤修复、形态发生和肿瘤转移过程中发挥重要作用,在肾脏的发育、急性损伤、再生中具有较强的作用。  相似文献   
184.
A case of chronic cerebral paragonimiasis westermani   总被引:1,自引:0,他引:1  
We report a chronic cerebral paragonimiasis from a 41-year-old Korean man who complains a headache and weakness of left motor neuron components. Magnetic resonance images of the brain revealed conglomerates of multiple ring-like enhancements in temporo-occipital and frontal lobes of the right hemisphere. An intradermal test for paragonimiasis westermani was positive. The patient was born near an endemic area of paragonimiasis and used to eat boiled or grilled freshwater crayfish in his childhood. Nodules in the brain were resected through craniotomies. The eggs of P. westermani were identified pathologically and parasitologically in the calcified necrotic lesions. Examinations on sputum and fecal specimens for the eggs of P. westermani were shown to be negative and a chest radiograph was normal. It is presumed that the brain lesions were formed by P. westermani approximately 30 years ago.  相似文献   
185.
186.
The purpose of this study was to investigate if multi-domain cognitive training, especially robot-assisted training, alters cortical thickness in the brains of elderly participants. A controlled trial was conducted with 85 volunteers without cognitive impairment who were 60 years old or older. Participants were first randomized into two groups. One group consisted of 48 participants who would receive cognitive training and 37 who would not receive training. The cognitive training group was randomly divided into two groups, 24 who received traditional cognitive training and 24 who received robot-assisted cognitive training. The training for both groups consisted of daily 90-min-session, five days a week for a total of 12 weeks. The primary outcome was the changes in cortical thickness. When compared to the control group, both groups who underwent cognitive training demonstrated attenuation of age related cortical thinning in the frontotemporal association cortices. When the robot and the traditional interventions were directly compared, the robot group showed less cortical thinning in the anterior cingulate cortices. Our results suggest that cognitive training can mitigate age-associated structural brain changes in the elderly.

Trial Registration

ClnicalTrials.gov NCT01596205  相似文献   
187.
An in-depth proteomic study of sheep milk whey is reported and compared to the data available in the literature for the cow whey proteome. A combinatorial peptide ligand library kit (ProteoMiner) was used to normalize protein abundance in the sheep whey proteome followed by an in-gel digest of a 1D-PAGE display and an in-solution digestion followed by OFFGEL isoelectric focusing fractionation. The peptide fractions obtained were then analyzed by LC-MS/MS. This enabled identification of 669 proteins in sheep whey that, to our knowledge, is the largest inventory of sheep whey proteins identified to date. A comprehensive list of cow whey proteins currently available in the literature (783 proteins from unique genes) was assembled and compared to the sheep whey proteome data obtained in this study (606 proteins from unique genes). This comparison revealed that while the 233 proteins shared by the two species were significantly enriched for immune and inflammatory responses in gene ontology analysis, proteins only found in sheep whey in this study were identified that take part in both cellular development and immune responses, whereas proteins only found in cow whey in this study were identified to be associated with metabolism and cellular growth.  相似文献   
188.

Background

Echocardiographic signs of constrictive physiology (CP) after pericardiocentesis are frequently observed in malignancy patients. The purpose of the current study was to explore whether features of CP after pericardiocentesis have prognostic impact in malignancy patients with pericardial effusion (PE).

Methods

We retrospectively reviewed 467 consecutive patients who underwent pericardiocentesis at our institution from January 2006 to May 2014. Among them, 205 patients with advanced malignancy who underwent comprehensive echocardiography after the procedure comprised the study population. Co-primary end points were all-cause mortality (ACM) and repeated drainage (RD) for PE. Patients were divided into four subgroups according to cytologic result for malignant cells and CP (positive cytology with negative CP, both positive, both negative, and negative cytology with positive CP).

Results

CP after pericardiocentesis was present in 106 patients (50%) at median 4 days after the procedure. During median follow-up of 208 days, ACM and RD occurred in 162 patients (79%) and 29 patients (14%), respectively. Cox regression analysis revealed that independent predictors for ACM were male gender and positive cytology (all, p < 0.05). For RD, predictors were positive cytology, the absence of cardiac tamponade, and negative CP after pericardiocentesis (all, p < 0.05). When the patients were divided into four subgroups, patients with negative cytology and positive CP demonstrated the most favorable survival (hazard ratio [HR]: 0.39, p = 0.005) and the lowest RD rates (HR: 0.07, p = 0.012).

Conclusion

CP after pericardiocentesis is common, but does not always imply poor survival or the need for RD in patients with advanced malignancies. On the contrary, the presence of CP in patients with negative cytology conferred the most favorable survival and the lowest rate of RD. Comprehensive echocardiographic evaluation for CP after pericardiocentesis would be helpful for predicting prognosis in patients with advanced malignancies.  相似文献   
189.
BackgroundScrub typhus is an acute febrile disease caused by Orientia tsutsugamushi infection. Recently, the rapid increase of scrub typhus incidence in several countries within the endemic region has become a serious public health issue. Despite the wide range of preventative approaches that have been attempted in the past 70 years, all have failed to develop an effective prophylactic vaccine. Currently, the selection of the proper antigens is one of the critical barriers to generating cross-protective immunity against antigenically-variable strains of O. tsutsugamushi.Conclusions/SignificanceImmunization of ScaA proteins provides protective immunity in mice when challenged with the homologous strain and significantly enhanced protective immunity against infection with heterologous strains. To our knowledge, this is the most promising result of scrub typhus vaccination trials against infection of heterologous strains in mouse models thus far.  相似文献   
190.
In this study, we report that one of the antimicrobial peptides scolopendrasin VII, derived from Scolopendra subspinipes mutilans, stimulates actin polymerization and the subsequent chemotactic migration of macrophages through the activation of ERK and protein kinase B (Akt) activity. The scolopendrasin VII-induced chemotactic migration of macrophages is inhibited by the formyl peptide receptor 1 (FPR1) antagonist cyclosporine H. We also found that scolopendrasin VII stimulate the chemotactic migration of FPR1-transfected RBL-2H3 cells, but not that of vector-transfected cells; moreover, scolopendrasin VII directly binds to FPR1. Our findings therefore suggest that the antimicrobial peptide scolopendrasin VII, derived from Scolopendra subspinipes mutilans, stimulates macrophages, resulting in chemotactic migration via FPR1 signaling, and the peptide can be useful in the study of FPR1-related biological responses. [BMB Reports 2015; 48(8): 479-484]  相似文献   
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