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81.
Applied Entomology and Zoology - The minute pirate bug Orius sauteri (Poppius) (Heteroptera: Anthocoridae) is a major natural enemy of micro-pests and is expected to be an effective pest-control...  相似文献   
82.
Gerodontology 2012; doi: 10.1111/j.1741‐2358.2012.00673.x Functional tooth units and nutritional status of older people in care homes in Indonesia Objectives: To investigate the relationship between functional tooth units (FTUs) and nutritional status. Methods: One hundred females (mean age: 72.4 ± 8.2 years) at four private care homes in Jakarta, Indonesia were interviewed and clinically examined. The oral examination included the assessment of teeth, prosthetic status, and number of FTUs. The total number of FTUs was further divided by tooth composition: natural tooth against natural tooth (NN‐FTUs), natural tooth against denture (ND‐FTUs), and denture against denture (DD‐FTUs). Nutritional status was evaluated using the body mass index (BMI) and the Mini Nutritional Assessment (MNA). Results: The mean numbers of teeth present, NN‐FTUs, ND‐FTUs, DD‐FTUs, and total FTUs were 13.1 ± 10.4, 1.7 ± 3.0, 1.2 ± 3.3, 0.4 ± 1.2 and 3.3 ± 4.4, respectively. The mean BMI and MNA scores were 24.8 ± 5.0 and 22.6 ± 2.8, respectively. Subjects with a normal BMI had a significantly higher total number of FTUs (3.6 ± 4.6) compared with underweight subjects (0.1 ± 0.3). Subjects with a normal MNA had a significantly higher number of NN‐FTU (2.6 ± 3.7) compared to those who were at risk or in a state of under‐nutrition (1.2 ± 2.4). Conclusion: This study revealed significant relationships between the number of FTUs and nutritional status. Keeping the posterior occlusion should be emphasized in order to maintain good nutritional status in older subjects.  相似文献   
83.
Retinoids are vitamin A derivatives with diverse biological functions. Both natural and artificial retinoids have been used as therapeutic reagents to treat human diseases, but not all retinoid actions are understood mechanistically. Plasma retinol binding protein (RBP) is the principal and specific carrier of vitamin A in the blood. STRA6 is the membrane receptor for RBP that mediates cellular vitamin A uptake. The effects of retinoids or related compounds on the receptor’s vitamin A uptake activity and its catalytic activities are not well understood. In this study, we dissected the membrane receptor-mediated vitamin A uptake mechanism using various retinoids. We show that a subset of retinoids strongly stimulates STRA6-mediated vitamin A release from holo-RBP. STRA6 also catalyzes the exchange of retinol in RBP with certain retinoids. The effect of retinoids on STRA6 is highly isomer-specific. This study provides unique insights into the RBP receptor’s mechanism and reveals that the vitamin A transport machinery can be a target of retinoid-based drugs.  相似文献   
84.
Type I collagen extracted from tendon, skin, and bone of wild type and prolyl 3-hydroxylase 1 (P3H1) null mice shows distinct patterns of 3-hydroxylation and glycosylation of hydroxylysine residues. The A1 site (Pro-986) in the α1-chain of type I collagen is almost completely 3-hydroxylated in every tissue of the wild type mice. In contrast, no 3-hydroxylation of this proline residue was found in P3H1 null mice. Partial 3-hydroxylation of the A3 site (Pro-707) was present in tendon and bone, but absent in skin in both α-chains of the wild type animals. Type I collagen extracted from bone of P3H1 null mice shows a large reduction in 3-hydroxylation of the A3 site in both α-chains, whereas type I collagen extracted from tendon of P3H1 null mice shows little difference as compared with wild type. These results demonstrate that the A1 site in type I collagen is exclusively 3-hydroxylated by P3H1, and presumably, this enzyme is required for the 3-hydroxylation of the A3 site of both α-chains in bone but not in tendon. The increase in glycosylation of hydroxylysine in P3H1 null mice in bone was found to be due to an increased occupancy of normally glycosylated sites. Despite the severe disorganization of collagen fibrils in adult tissues, the D-period of the fibrils is unchanged. Tendon fibrils of newborn P3H1 null mice are well organized with only a slight increase in diameter. The absence of 3-hydroxyproline and/or the increased glycosylation of hydroxylysine in type I collagen disturbs the lateral growth of the fibrils.  相似文献   
85.
Exercise enhances insulin sensitivity in skeletal muscle, but the underlying mechanism remains obscure. Recent data suggest that alternatively activated M2 macrophages enhance insulin sensitivity in insulin target organs such as adipose tissue and liver. Therefore, the aim of this study was to determine the role of anti-inflammatory M2 macrophages in exercise-induced enhancement of insulin sensitivity in skeletal muscle. C57BL6J mice underwent a single bout of treadmill running (20 m/min, 90 min). Twenty-four hours later, ex vivo insulin-stimulated 2-deoxy glucose uptake was found to be increased in plantaris muscle. This change was associated with increased number of CD163-expressing macrophages (i.e. M2-polarized macrophages) in skeletal muscle. Systemic depletion of macrophages by pretreatment of mice with clodronate-containing liposome abrogated both CD163-positive macrophage accumulation in skeletal muscle as well as the enhancement of insulin sensitivity after exercise, without affecting insulin-induced phosphorylation of Akt and AS160 or exercise-induced GLUT4 expression. These results suggest that accumulation of M2-polarized macrophages is involved in exercise-induced enhancement of insulin sensitivity in mouse skeletal muscle, independently of the phosphorylation of Akt and AS160 and expression of GLUT4.  相似文献   
86.

Background

A previous study has demonstrated that endurance training under hypoxia results in a greater reduction in body fat mass compared to exercise under normoxia. However, the cellular and molecular mechanisms that underlie this hypoxia-mediated reduction in fat mass remain uncertain. Here, we examine the effects of modest hypoxia on adipocyte function.

Methods

Differentiated 3T3-L1 adipocytes were incubated at 5% O2 for 1 week (long-term hypoxia, HL) or one day (short-term hypoxia, HS) and compared with a normoxia control (NC).

Results

HL, but not HS, resulted in a significant reduction in lipid droplet size and triglyceride content (by 50%) compared to NC (p < 0.01). As estimated by glycerol release, isoproterenol-induced lipolysis was significantly lowered by hypoxia, whereas the release of free fatty acids under the basal condition was prominently enhanced with HL compared to NC or HS (p < 0.01). Lipolysis-associated proteins, such as perilipin 1 and hormone-sensitive lipase, were unchanged, whereas adipose triglyceride lipase and its activator protein CGI-58 were decreased with HL in comparison to NC. Interestingly, such lipogenic proteins as fatty acid synthase, lipin-1, and peroxisome proliferator-activated receptor gamma were decreased. Furthermore, the uptake of glucose, the major precursor of 3-glycerol phosphate for triglyceride synthesis, was significantly reduced in HL compared to NC or HS (p < 0.01).

Conclusion

We conclude that hypoxia has a direct impact on reducing the triglyceride content and lipid droplet size via decreased glucose uptake and lipogenic protein expression and increased basal lipolysis. Such an hypoxia-induced decrease in lipogenesis may be an attractive therapeutic target against lipid-associated metabolic diseases.  相似文献   
87.
Effects of various factors including incubation time, water content of airdried cells, concentration and pH of KH2PO4–K2HPO4 mixture, d-glucose concentration, MgSO4 concentration, GMP concentration, cell concentration, aeration and various kinds of carbohydrates on the fermentative production of GDP-mannose, GDP and GTP from 5′-GMP by air-dried cells of baker’s yeast were investigated. The water content of air-dried cells was the most important factor in the fermentation. When the air-dried cells of baker’s yeast (100 mg/ml) were incubated with 5′-GMP (20 μmoles/ml), d-glucose (800 μmoles/ml), potassium phosphate buffer (360 μmoles/ml, pH 7.0), and MgSO4 (20 μmoles/ml), 2-hr incubation gave GDP in 20% yield and GTP in 61.1% yield, GDP-mannose being produced in 45% yield after 8-hr incubation. The phosphorylation of 5′-AMP, 5′-dAMP, 5′-dGMP 5′-CMP and 5′-UMP was also observed in high yields under the same conditions.  相似文献   
88.
Transforming growth factor (TGF) β1-induced plasminogen activator inhibitor (PAI)-1 is one of factors associated with the development of hepatic fibrosis. Calcitonin gene-related peptide (CGRP) shows hepatoprotective effect during hepatic injuries, including fibrosis. However, the effects of CGRP on PAI-1 expression induced by TGFβ1 are unknown. In this study, we investigated the effect of CGRP on TGFβ1-induced PAI-1 expression and its regulatory mechanisms in HepG2 cells. CGRP inhibited TGFβ1-induced PAI-1 expression. H89, a protein kinase A inhibitor, abolished the inhibition of TGFβ1-induced PAI-1 expression by CGRP. TGFβ1 activated mitogen-activated protein kinase (MAPK), including extracellular signal-regulated kinase, c-jun NH2-terminal kinase, and p38, and this activation was abolished by CGRP. These results show that the CGRP-induced cAMP/PKA activation suppresses activation of MAPK induced by TGFβ1, leading to decreased PAI-1 expression in HepG2 cells.  相似文献   
89.
90.
We validated the effects of a passive integrated transponder (PIT) tagging process on the oriental weather loach Misgurnus anguillicaudatus. Laboratory experiments were conducted to assess the effects of PIT tagging on fish survival, growth, wound healing, and tag omission. Two tagging protocols, standard syringe injection versus insertion through a small hole pierced by a fine needle-shaped awl, were compared using a 12.5 × 2.07 mm2 tag. A control group was also included. In comparison with the awl technique, syringe injection heightened the mortality of the loach and delayed healing of the wound caused by tag insertion. No effects of either PIT tagging method were detected on the growth of surviving loach. We also field-tested similarly tagged populations within a river-based irrigation system of Sado Island, Japan. Two different sized tags (long, 12.5 × 2.07 mm2; short, 8.5 × 2.12 mm2) were compared by using antenna loggers which detected fish movement through gates and automatically logged tagged fish’s tag IDs and timestamps. By comparing logged data and actual fish collection surveys both below and above the gates, 77% and 30% of actual loach movements were confirmed to have been successfully logged for the long and short tags, respectively. The awl insertion technique with the longer tag is therefore recommended for use in similar studies of smaller fish species.  相似文献   
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