903 research outputs found
Brown Adipose Tissue PPARĪ³ Is Required for the Insulin-Sensitizing Action of Thiazolidinediones
Brown adipose tissue (BAT) plays a critical role in metabolic homeostasis. BAT dysfunction is associated with the development of obesity through an imbalance between energy expenditure and energy intake. The nuclear receptor peroxisome proliferator-activated receptor gamma (PPARĪ³) is the master regulator of adipogenesis. However, the roles of PPARĪ³ and thiazolidinediones (TZDs) in the regulation of BAT metabolism remain unclear. TZDs, which are selective PPARĪ³ activators, improve systemic insulin resistance in animals and humans. In the present study, we generated brown adipocyte-specific PPARĪ³-deficient mice (BATĪ³KO) to examine the in vivo roles of PPARĪ³ and TZDs in BAT metabolism. In electron microscopic examinations, brown adipocyte-specific PPARĪ³ deletion promoted severe whitening of brown fat and morphological alteration of mitochondria. Brown adipocyte-specific PPARĪ³ deletion also reduced mRNA expression of BAT-selective genes. Although there was no difference in energy expenditure between control and BATĪ³KO mice in calorimetry, norepinephrine-induced thermogenesis was impaired in BATĪ³KO mice. Moreover, pioglitazone treatment improved diet-induced insulin resistance in the control mice but not in the BATĪ³KO mice. These findings suggest that BAT PPARĪ³ is necessary for the maintenance of brown adipocyte function and for the insulin-sensitizing action of TZDs
Affine Kac-Moody Groups as Twisted Loop Groups obtained by Galois Descent Considerations
We provide explicit generators and relations for the affine Kac-Moody groups, as well as a realization of them as (twisted) loop groups by means of Galois descent considerations. As a consequence, we show that the affine Kac-Moody group of type X(r) N is isomorphic to the
fixed-point subgroup of the affine Kac-Moody group of type X(1) N under an action of the Galois group
Kinematic characteristics of barefoot sprinting in habitually shod children
Background. Anecdotally, a wide variety of benefits of barefoot running have been advocated by numerous individuals. The influence of the alterations in the properties of the shoe on the running movement has been demonstrated in adults at submaximal jogging speeds. However, the biomechanical differences between shod and barefoot running in children at sprinting speeds and the potential developmental implications of these differences are still less examined. The purpose was to determine the potential differences in habitually shod children's sprint kinematics between shod and barefoot conditions. Methods. Ninety-four children (51 boys and 43 girls; 6-12 years-old; height, 135.0 Ā± 0.12 m; body mass, 29.0 Ā± 6.9 kg) performed 30 m maximal sprints from standing position for each of two conditions (shod and barefoot). To analyze sprint kinematics within sagittal plane sprint kinematics, a high-speed camera (300 fps) was set perpendicular to the runway. In addition, sagittal foot landing and take-offimages were recorded for multiple angles by using five high-speed cameras (300 fps). Spatiotemporal variables, the kinematics of the right leg (support leg) and the left leg (recovery leg), and foot strike patterns: rear-foot strike (RFS), mid-foot strike (MFS), and forefoot strike (FFS) were investigated. The paired t -test was used to test difference between shod and barefoot condition. Results. Barefoot sprinting in habitually shod children was mainly characterized by significantly lower sprint speed, higher step frequency, shorter step length and stance time. In shod running, 82% of children showed RFS, whereas it decreased to 29% in barefoot condition. The touch down state and the subsequent joint movements of both support and recovery legs during stance phase were significantly altered when running in condition with barefoot. Discussion. The acute effects of barefoot sprinting was demonstrated by significantly slower sprinting speeds that appear to reflect changes in a variety of spatiotemporal parameters as well as lower limb kinematics. It is currently unknown whether such differences would be observed in children who typically run in bare feet and what developmental benefits and risks may emerge from increasing the proportion of barefoot running and sprinting in children. Future research should therefore investigate potential benefits that barefoot sprinting may have on the development of key physical fitness such as nerve conduction velocity, muscular speed, power, and sprinting technique and on ways to minimize the risk of any acute or chronic injuries associated with this activity. Ā© 2018 Mizushima et al
MCM8-9 complex promotes resection of double-strand break ends by MRE11-RAD50-NBS1 complex.
MCM8-9 complex is required for homologous recombination (HR)-mediated repair of double-strand breaks (DSBs). Here we report that MCM8-9 is required for DNA resection by MRN (MRE11-RAD50-NBS1) at DSBs to generate ssDNA. MCM8-9 interacts with MRN and is required for the nuclease activity and stable association of MRN with DSBs. The ATPase motifs of MCM8-9 are required for recruitment of MRE11 to foci of DNA damage. Homozygous deletion of the MCM9 found in various cancers sensitizes a cancer cell line to interstrand-crosslinking (ICL) agents. A cancer-derived point mutation or an SNP on MCM8 associated with premature ovarian failure (POF) diminishes the functional activity of MCM8. Therefore, the MCM8-9 complex facilitates DNA resection by the MRN complex during HR repair, genetic or epigenetic inactivation of MCM8 or MCM9 are seen in human cancers, and genetic inactivation of MCM8 may be the basis of a POF syndrome
Investigation of Bacteria from Spoiled Bottled Salad Dressing Leading to Gas Explosion
Background: In 2020, an incident involving spoiled salad dressing from a commercial source occurred. Upon opening the bottle, the contents exploded from gas that seemed to have fermented inside the bottle. For safety concerns, we sought to investigate the bacteria from the salad dressing in order to notify the company that made the product and relevant authorities. Methods: Anaerobic and carbon dioxide culture methods were used. To determine species of colonies, MALDI-TOF-MS and 16S rRNA whole sequencing were performed. Results: There were no colonies grown in anaerobic condition; however, we obtained three colonies from the carbon dioxide atmosphere. We determined the first colony as Alkalihalobacillus clausii (Bacillus clausii), the second as Bacillus spp. such as B. australimaris, B. safensis or B. safensis subsp. osmophilus and the third as B. paralicheniformis. Phylogenic tree analysis using the16S rRNA sequence revealed these colonies to be in a proximity of known gas-producing species. The NCBI database search revealed that a key gas production pathway gene, pyruvate formate-lyase (pfl), of which the gene product catalyzes pyruvate to formate conversion, exists in B. paralicheniformis. Formate dehydrogenase (FdhH) produces CO2 from formate that the coding gene fdhF positive bacteria can participate in gas production when formate is present in the culture. And we found fdhF from A. clausii, B. australimaris/B. safensis and B. paralicheniformis. Furthermore, under butanediol producing pathway, genes coding two enzymes involved in CO2 production, namely als and ald, existed in B. australimaris/B. safensis and B paralicheniformis, whereas A. clausii possessed als. Conclusion: Candidate species A. clausii, B. australimaris/B. safensis and B. paralicheniformis from spoiled salad dressing were thought to produce CO2 gas each from their own enzymes, or in combination, which caused the explosion upon opening. The endospore forming nature of Bacillus should alert us to be cautious when considering food producing process regulations where we need to thoroughly heat any product during manufacture in order to inactivate any bacteria as there is the possibility of this type of dangerous occurrence
Diel changes in the vertical distribution of larval cutlassfish Trichiurus japonicus
Diel vertical migration of the cutlassfish Trichiurus japonicus larvae were investigated by consecutive 24-h collections at 3-h intervals at a station in the central Seto Inland Sea, Japan in June and September. Only one larva was collected in June 2017, while 224 and 40 larvae were collected in September 2016 and 2017, respectively. Larvae were present only at depths of ā„ 11 m during the day, whereas they were present at depths of 1, 6, 11 and 16 m during the night. Migration was observed in larvae in which swim bladder formation was completed. A similar pattern, namely nocturnal occurrence at shallow depths only of the developed larvae, was observed in another 24-h survey, suggesting that the swim bladder regulates the upward movement of larvae at night.This work was partly supported by the Environment Research and Technology Development Fund (S-13) granted by the Ministry of the Environment, Japan
Long-term effects of school barefoot running program on sprinting biomechanics in children: A case-control study
Renormalization of potentials and generalized centers
We generalize the Riesz potential of a compact domain in by
introducing a renormalization of the -potential for .
This can be considered as generalization of the dual mixed volumes of convex
bodies as introduced by Lutwak. We then study the points where the extreme
values of the (renormalized) potentials are attained. These points can be
considered as a generalization of the center of mass. We also show that only
balls give extreme values among bodied with the same volume.Comment: Adv. Appl. Math. 48 (2012), 365--392 Figure 11 has been corrected
after publication. Theorem 3.12 and the exposition of Lemma 2.15 are modified
in version
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