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81.
Cooke PS Holsberger DR Cimafranca MA Meling DD Beals CM Nakayama K Nakayama KI Kiyokawa H 《Obesity (Silver Spring, Md.)》2007,15(6):1400-1408
Objective: The etiology of some obesity may involve adipocyte hyperplasia. However, the role of adipocyte number in establishing adipose mass is unclear. Cyclin‐dependent kinase inhibitor p27 regulates activity of cyclin/cyclin‐dependent kinase complexes responsible for cell cycle progression. This protein is critical for establishing adult adipocyte number, and p27 knockout increases adult adipocyte number. The SCF (for Skp1‐Cullin‐F‐box protein) complex targets proteins such as p27 for ubiquitin‐proteosome degradation; the F box protein S phase kinase‐associated protein 2 (Skp2), a component of the SCF complex, specifically recognizes p27 for degradation. We used Skp2 knockout (Skp2?/?) mice to test whether Skp2 loss decreased adipose mass and adipocyte number. Research Methods and Procedures: We measured body weight, adipose mass, adipocyte diameter and number, and glucose tolerance in wild‐type (WT), Skp2?/?, and p27?/?Skp2?/? mice. Mouse embryo fibroblasts (MEFs) from WT and Skp2?/? fetuses were differentiated to determine whether Skp2 directly affected adipogenesis. Results: Skp2?/? mice had a 50% decrease in both subcutaneous and visceral fat pad mass and adipocyte number; these decreases exceeded those in body weight, kidney, or muscle. To test the hypothesis that Skp2 effects on adipocyte number involved p27 accumulation, we used p27?/?Skp2?/? double knockout mice. The Skp2?/? decrements in adipocyte number and fat pad mass were totally reversed in p27?/?Skp2?/? mice. Adipogenesis was inhibited in MEFs from Skp2?/? vs. WT mice, and this inhibition was absent in MEFs from p27?/?Skp2?/? mice. Discussion: Our results indicate that Skp2 regulates adipogenesis and ultimate adipocyte number in vivo; thus, Skp2 may contribute to obesity involving adipocyte hyperplasia. 相似文献
82.
A soft actuator mimicking natural muscles (artificial muscle) has been developed using a flexible conducting polymer of polypyrrole films, which were driven by electrical stimulus in a saline solution. The work characteristics were studied under various load stresses and found to behave like natural muscles. The artificial muscles shrunk and stiffened by the positive electrical stimulus by 2-3% at the maximum force of 5 MPa, and relaxed by application of negative voltages. At larger load stresses, the artificial muscle shrunk slowly as natural muscles do. The driving current also lasted longer at larger loads, indicating that the muscle sensed the magnitude of the load stress. During contraction of the muscle, the conversion efficiency from the electrical input and mechanical output energies was estimated to be around 0.06%. The maximum volumetric work was approximately estimated to be 100 kJ m(-3). These figures are unexpectedly small compared with those of natural muscles. 相似文献
83.
84.
Disruption of phospholipase B gene, PLB1, increases the survival of baker's yeast Torulaspora delbrueckii 总被引:2,自引:0,他引:2
Abstract An uracil auxotrophic mutant of baker's yeast Torulaspora delbrueckii , which is resitant to 5-fluoro-orotic acid, was complemented by transformation with YEp24 which harbors 2 μm origin and URA3 derived from Saccharomyces cerevisiae . The phospholipase B in T. delbrueckii cells is active in both acidic and alkaline conditions. However, activity of phospholipase B gene ( PLB1 ) in cells of disruption mutant ( plbI : : URA3 ) was lost in both conditions, which indicates that all phospholipase B activity is encoded by a single gene (or a single polypeptide) in these yeast cells. Over-expression of PLB1 with YEp plasmid vector in T. delbrueckii cells showed ∼ 2.5-fold increase in phospholipase B activity, comparing with that in wild-type cells. Cells of plb1 Δ mutant showed increased survival when cells of plb1 Δ mutant and wild-type strain were incubated in water at 30 °C. Cells of PLB1 -over-expressed strain died rapidly even during the cultivation period, indicating that phospholipase B activity may be a determinant for the survival of this yeast. 相似文献
85.
Yuji Shimizu Shimpei Sato Jun Koyamatsu Hirotomo Yamanashi Mako Nagayoshi Koichiro Kadota Mami Tamai Kazuhiko Arima Hironori Yamasaki Yosuke Kusano Noboru Takamura Takahiro Maeda 《Journal of physiological anthropology》2014,33(1):7
Background
Renal impairment is known to be associated with atherosclerosis, which in turn is reported to be positively associated with hemoglobin levels. In addition, renal impairment is known to be associated with a form of anemia known as renal anemia.Methods
To clarify the associations between renal impairment and anemia, we conducted a cross-sectional study of 1,105 60 to 89-year-old men, who were not taking medication for anemia and were undergoing general health check-ups.Results
Compared with non-chronic kidney disease, chronic kidney disease (CKD) with a glomerular filtration rate (GFR) <60 mL/min/1.73 m2 was found to constitute a significant risk of anemia. However, we noted that this risk was lower for mild renal impairment (60 mL/min/1.73 m2 ≤ GFR <90 mL/min/1.73 m2). Compared with the non-CKD reference group, the classical cardiovascular risk factors adjusted odds ratio (OR) for anemia was 1.81 (1.23 to 2.68) and compared with the normal renal function (GFR ≥90 mL/min/1.73 m2) reference group, the ORs for mild renal impairment and CKD were 0.26 (0.15 to 0.47) and 0.60 (0.33 to 1.09).Conclusions
Independent from classical cardiovascular risk factors, CKD, which was identified during general health check-ups, appeared to constitute a significant risk of anemia for older Japanese men. For mild renal impairment, however, this association was a reduced risk of anemia and thus possibly a higher risk of atherosclerosis. 相似文献86.
Keiichi Hata Naohiro Kobayashi Keita Sugimura Weihua Qin Deis Haxholli Yoshie Chiba Sae Yoshimi Gosuke Hayashi Hiroki Onoda Takahisa Ikegami Christopher
B Mulholland Atsuya Nishiyama Makoto Nakanishi Heinrich Leonhardt Tsuyoshi Konuma Kyohei Arita 《Nucleic acids research》2022,50(21):12527
Ubiquitin-like with PHD and RING finger domain-containing protein 1 (UHRF1)-dependent DNA methylation is essential for maintaining cell fate during cell proliferation. Developmental pluripotency-associated 3 (DPPA3) is an intrinsically disordered protein that specifically interacts with UHRF1 and promotes passive DNA demethylation by inhibiting UHRF1 chromatin localization. However, the molecular basis of how DPPA3 interacts with and inhibits UHRF1 remains unclear. We aimed to determine the structure of the mouse UHRF1 plant homeodomain (PHD) complexed with DPPA3 using nuclear magnetic resonance. Induced α-helices in DPPA3 upon binding of UHRF1 PHD contribute to stable complex formation with multifaceted interactions, unlike canonical ligand proteins of the PHD domain. Mutations in the binding interface and unfolding of the DPPA3 helical structure inhibited binding to UHRF1 and its chromatin localization. Our results provide structural insights into the mechanism and specificity underlying the inhibition of UHRF1 by DPPA3. 相似文献
87.
Masahiro Tsuchiya Fukie Niijima-Yaoita Hiroyuki Yoneda Ko Chiba Shinobu Tsuchiya Yoshihiro Hagiwara Keiichi Sasaki Shunji Sugawara Yasuo Endo Koichi Tan-No Makoto Watanabe 《Life sciences》2014
Aims
Dietary habits are crucial factors affecting metabolic homeostasis. However, few animal experiments have addressed the effects of long-term feeding with soft food on parameters reflecting systemic health.Main methods
Using mice, we compared the effects of short (3 days) and long (17 weeks from weaning) feeding periods between powdered food and normal pellet food on the levels of blood glucose, serum levels of insulin, catecholamines, and corticosterone, blood pressure, and/or social interaction behaviors. In addition, the effects of a human glucagon-like peptide-1 analog, liraglutide (a new drug with protective effects against neuronal and cardiovascular diseases), were compared between the powder and pellet groups.Key finding
(i) Powdered food, even for such a short period, resulted in a greater glycemic response than pellet food, consistent with powdered food being more easily digested and absorbed. (ii) Long-term feeding on powdered food induced hyperglycemia and related systemic signs of illness, including increases in serum adrenaline, noradrenaline, and corticosterone, higher blood pressures (especially diastolic), and increased social interaction behaviors. (iii) Liraglutide, when administered subcutaneously for the last 2 weeks of the 17-week period of feeding, improved these changes (including those in social interaction behaviors).Significance
The hyperglycemia associated with long-term powdered-food feeding may lead to certain systemic illness signs, such as elevations of blood glucose, hypertension, and abnormal behaviors in mice. Mastication of food of adequate hardness may be very important for the maintenance of systemic (physical and mental) health, possibly via reduction in the levels of blood glucose and/or adrenal stress hormones (catecholamines and glucocorticoids). 相似文献88.
89.
Ayaka Endo Akio Kawamura Hiroaki Miyata Shigetaka Noma Masahiro Suzuki Takashi Koyama Shiro Ishikawa Susumu Nakagawa Shunsuke Takagi Yohei Numasawa Keiichi Fukuda Shun Kohsaka JCD-KICS Investigators 《PloS one》2015,10(6)
Objective
We devised a percutaneous coronary intervention (PCI) scoring system based on angiographic lesion complexity and assessed its association with in-hospital complications.Background
Although PCI is finding increasing application in patients with coronary artery disease, lesion complexity can lead to in-hospital complications.Methods
Data from 3692 PCI patients were scored based on lesion complexity, defined by bifurcation, chronic total occlusion, type C, and left main lesion, along with acute thrombus in the presence of ST-segment elevation myocardial infarction (1 point assigned for each variable).Results
The patients’ mean age was 67.5 +/- 10.8 years; 79.8% were male. About half of the patients (50.3%) presented with an acute coronary syndrome, and 2218 (60.1%) underwent PCI for at least one complex lesion. The patients in the higher-risk score groups were older (p < 0.001) and had present or previous heart failure (p = 0.02 and p = 0.01, respectively). Higher-risk score groups had significantly higher in-hospital event rates for death, heart failure, and cardiogenic shock (from 0 to 4 risk score; 1.7%, 4.5%, 6.3%, 7.1%, 40%, p < 0.001); bleeding with a hemoglobin decrease of >3.0 g/dL (3.1%, 11.0%, 13.1%, 10.3%, 28.6%, p < 0.001); and postoperative myocardial infarction (1.5%, 3.1%, 3.8%, 3.8%, 10%, p = 0.004), respectively. The association with adverse outcomes persisted after adjustment for known clinical predictors (odds ratio 1.72, p < 0.001).Conclusion
The complexity score was cumulatively associated with in-hospital mortality and complication rate and could be used for event prediction in PCI patients. 相似文献90.
Ando K Ishikura K Nakakugi T Shimono Y Tamai T Sugawa M Limviroj W Chinzei Y 《The Journal of parasitology》2001,87(1):96-100
Five persons from 2 families residing at Miyama Town, Mie Prefecture, Japan, ingested fresh raw fish Oncorhynchus sp. on 9 May 1999 that was caught at Owase district in Mie. They all expelled diphyllobothriid cestodes 11-37 days after ingesting the fish. The parasites were morphologically identical to Diphyllobothrium nihonkaiense Yamane et al., 1986. Five plerocercoids were detected from a portion of the fish. Nucleotide sequence of a region of the cytochrome c oxidase subunit I gene of mitochondrial DNA from an adult worm was identical with that from the plerocercoid. The fish was identified as Oncorhynchus masou ishikawae according to the nucleotide sequence of the nuclear ribosomal second internal transcribed spacer region II gene. This is the first record of D. nihonkaiense plerocercoids from O. m. ishikawae. 相似文献