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81.
Tubular injury is one of the important determinants of progressive renal failure in diabetic nephropathy (DN), and TGF-β1 has been implicated in the pathogenesis of tubulointerstitial disease that characterizes proteinuric renal disease. The aim of this study was to identify novel therapeutic target molecules that play a role in the tubule damage of DN. We used an LC-MS/MS-based proteomic technique and human renal proximal epithelial cells (HRPTECs). Urine samples from Japanese patients with type 2 diabetes (n = 46) were used to quantify the candidate protein. Several proteins in HRPTECs in cultured media were observed to be driven by TGF-β1, one of which was 33-kDa IGFBP7, which is a member of IGFBP family. TGF-β1 up-regulated the expressions of IGFBP7 mRNA and protein in a dose- and time-dependent fashion via Smad2 and 4, but not MAPK pathways in HRPTECs. In addition, the knockdown of IGFBP7 restored the TGF-β1-induced epithelial to mesenchymal transition (EMT). In the immunohistochemical analysis, IGFBP7 was localized to the cytoplasm of tubular cells but not that of glomerular cells in diabetic kidney. Urinary IGFBP7 levels were significantly higher in the patients with macroalbuminuria and were correlated with age (r = 0.308, p = 0.037), eGFR (r = −0.376, p = 0.01), urinary β2-microglobulin (r = 0.385, p = 0.008), and urinary N-acetyl-beta-D-glucosaminidase (NAG) (r = 0.502, p = 0.000). A multivariate regression analysis identified urinary NAG and age as determinants associated with urinary IGFBP7 levels. In conclusion, our data suggest that TGF-β1 enhances IGFBP7 via Smad2/4 pathways, and that IGFBP7 might be involved in the TGF-β1-induced tubular injury in DN.  相似文献   
82.
In this study we examined the effect of the specific gravity of culture medium on the frequency of hematopoietic stem cell (HSC) maintenance. We used a newly developed high-specific-gravity media. Bone marrow cells were isolated and cultured, and HSC activity was evaluated. The number of hematopoietic progenitor/stem cells was markedly higher in the medium with high specific gravity. In high-specific-gravity media, cells did not precipitate, maintenance of HSCs was increased, and there was a concomitant accumulation of beta-catenin. This novel technique for maintaining HSC populations provides an important new tool for studies in regenerative medicine.  相似文献   
83.
Summary The relationship between granule density, protein content, and Ca and S contents were studied in two secretory granule fractions, from parotid glands of the rat, previously shown to constitute different stages in granule maturation. The density of the lighter fraction was between 1.133 and 1.142 g/ml, while that of the heavier fraction was greater than 1.142 g/ml. The mean protein content of the denser granules was 12% greater than that of the lighter granules (P<0.03), while the dry-mass elemental concentrations in the two granule fractions were unchanged. These results indicate that protein is added to granules during the maturation process (presumably by vesicular traffic), and that the resulting increase in granule density is not driven simply by decrease in water content and/or increased concentrations of inorganic Ca or S in the granules. The elemental concentration values also indicate that the diffusible elements permeate the granule membrane during the fractionation procedures.  相似文献   
84.
To examine the association of the ATP-binding cassette transporter 1 (ABCA1) gene with type 2 diabetes (DM), we studied genetic polymorphisms of the ABCA1 gene including its linkage disequilibrium (LD) and haplotype analyses using a Japanese population. A sample set (DM:72, IGT:75, and NGT:227) was genotyped with 34 SNPs distributed from the promoter region to the last exon of the ABCA1 gene. LD between SNPs was assessed in pairwise manner. Among 13 LD blocks constructed, an LD block at the 5'-region showed a significant difference in the haplotype distribution between the study groups (NGT vs. IGT + DM: overall p = 0.0180; NGT vs. DM: 0.0001). Fisher's exact probability test (NGT vs. DM) showed a significant association of the haplotype 2 of the LD block (p = 0.0001), with an odds ratio (OR) of 2.53 (95%CI:1.62-4.12). Diplotype analysis also showed a significant association of the diplotypes with the haplotype 2 (OR:2.59, 95%CI:1.48-4.54, p = 0.0013).  相似文献   
85.
We investigated the spawning nests of Gymnogobius macrognathos on a tidal flat in the Tatara River, Fukuoka Prefecture, Japan. Digging uncovered 19 spawning nests. The number of eggs and the standard length of the guarding male were positively correlated. Nine spawning nests were examined using in situ resin casting. All casts had structures characteristic of callianassid shrimp burrows and were most likely those of Nihonotrypaea japonica. Spawning nests had significantly greater average diameters than shrimp burrow openings and may have been widened by G. macrognathos.  相似文献   
86.
Understanding how social relationships affect long-term stress is important because stress has a profound impact on the welfare of animals and social relationships often exert a strong influence on their stress responses. The purpose of this study was to investigate the relationship between social behaviors and long-term stress levels as assessed by hair cortisol (HC) concentration. The subjects were 11 chimpanzees living in an all-male group (divided into two sub-groups) in Kumamoto Sanctuary, Kyoto University, Japan. Behavioral data were collected between December 2014 and March 2015. The total observation time was 129 h. Hair samples were collected in late March and early April 2015, and cortisol was extracted from the hair and measured with enzyme immunoassay. The hair growth rate was estimated to be 1.33 ± 0.06 cm/month. The results revealed that there was a positive correlation between the rate of receiving aggression and HC levels. We also found a significant negative correlation between the balance between giving and receiving grooming (grooming balance index: GBI), which was calculated by subtracting the rate with which grooming is given from that with which it is received, and the rate of receiving aggression and between the GBI and HC levels. Thus, individuals receiving higher levels of aggression also tended to give grooming for relatively long periods compared to the time they were being groomed. In contrast, the rate of initiating aggression did not have a relationship with either HC levels or any measure of social grooming. We did not find social buffering effects, as there was no correlation between mutual social grooming and HC levels. These results show that not only aggressive interactions but also overall social situations in which animals do not have balanced relationships with others might result in the long-term elevation of cortisol levels in captive male chimpanzees.  相似文献   
87.
88.
Mouthparts of Leptotrombidium larvae (Acariformes: Trombiculidae), potential vectors of tsutsugamushi disease agents, were studied in detail using light microscopy, scanning electron microscopy, and transmission electron microscopy. The mouthparts incorporated within the pseudotagma gnathosoma are composed of the infracapitulum ventrally and the chelicerae dorsally. The ventral wall of the infracapitulum is formed by a wide mentum posteriorly and a narrowed malapophysis anteriorly. The malapophysis firmly envelops the distal cheliceral portions by its lateral walls. The lateral lips of the malapophysis are flexible structures hiding the cheliceral blades in inactive condition and turning back forming a type of temporary sucker closely applied to the host skin during feeding. The roof of the infracapitulum is formed by a weakly sclerotized labrum anteriorly and a cervix with the capitular apodemes extending posteriorly. The labral muscles are lacking. The capitular apodemes serve as origin for pharyngeal dilators running to the dorsal wall of the pharynx fused with the bottom of the infracapitulum. The basal cheliceral segments are separated from each other besides the very posterior portions where they are movably joined by the inner walls. The sigmoid pieces serve for insertion of the cheliceral elevators originating at the posterior portions of the basal segments. The movable digits reveal the solid basal sclerite and the cheliceral blade curved upward with a tricuspid cap on its tip. Dendrites of nerve cells run along the digits to their tips. The ganglia are placed within the basal segments just behind the movable digits. The chelicerae also reveal well developed flexible fixed digits overhanging the basal portions of the blades. The gnathosoma possesses several sets of extrinsic muscles originating at the scutum and at the soft cuticle behind it. Laterally, the gnathosoma bears five‐segmented palps with a trifurcate palpal claw. J. Morphol. 277:424–444, 2016. © 2016 Wiley Periodicals, Inc.  相似文献   
89.
On age relationships of mineral contents in human bones, the contents of the sixth rib and a piece of its compact bone were determined by inductively coupled plasma atomic emission spectrometry (ICPS). The ribs were resected from 21 subjects (14 men and 7 women) who died in age ranging from 65 to 93 yr. There were no age-dependent decreases in Ca and P contents of the ribs in the age range on ICPS. It was found that there were no age-dependent decreases in Ca and P in compact bones of ribs.  相似文献   
90.
We compared the relaxant effect of original pituitary adenylate cyclase-activating peptide (PACAP)1-27 with that of a newly developed, synthetic PACAP1-27 analogue, [Arg15,20,21 Leu17]-PACAP-Gly-Lys-Arg-NH2, in human bronchi in vitro (n=4-5 in each group). Using precontraction by carbachol (0.1 microM), cumulative administration of PACAP1-27 and salbutamol caused concentration-dependent smooth muscle relaxation with similar potencies and maximum relaxant effects. Non-cumulative administration of the PACAP1-27 analogue and the original PACAP1-27 caused concentration-dependent relaxation with a similar maximum relaxant effect and potency as well. However, the onset and offset of action was markedly slower for the PACAP1-27 analogue than for the original PACAP1-27 (>90% versus <10% of peak relaxation remaining 5 h after administration). Peptidase inhibition by captopril (10 microM) and phosphoramidon (1 microM) significantly increased the maximum relaxant effect and duration of action of PACAP1-27 but not of the PACAP1-27 analogue, during the 3 h of observation in the human bronchi. We conclude that [Arg15,20,21 Leu17]-PACAP-Gly-Lys-Arg-NH2 produces significant concentration-dependent and sustained bronchial smooth muscle relaxation in vitro. The sustained relaxant effect is due, at least in part, to the synthetic PACAP1-27 analogue being less susceptible to cleavage by peptidases than the original peptide PACAP1-27.  相似文献   
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