67 research outputs found

    Dark age consistency in the 21cm global signal

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    We propose a new observable for the 21cm global signal during the dark ages, the dark-age consistency ratio, which is motivated from the fact that the shape of the functional form of the brightness temperature against the frequency is cosmological-parameter independent in the standard Λ\LambdaCDM model. The dark-age consistency ratio takes a certain definite value in the Λ\LambdaCDM case, which can serve as a critical test of the model and probe those beyond the standard one. The new observable just needs measurements of the brightness temperature at a few frequency bands during the dark ages, and thus it allows us to test cosmological scenarios even with limited information on the global signal.Comment: 6 pages, 4 figure

    New femoral remains of <i>Nacholapithecus kerioi</i>: Implications for intraspecific variation and Miocene hominoid evolution

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    The middle Miocene stem kenyapithecine Nacholapithecus kerioi (16-15 Ma; Nachola, Kenya) is represented by a large number of isolated fossil remains and one of the most complete skeletons in the hominoid fossil record (KNM-BG 35250). Multiple fieldwork seasons performed by Japanese-Kenyan teams during the last part of the 20th century resulted in the discovery of a large sample of Nacholapithecus fossils. Here, we describe the new femoral remains of Nacholapithecus. In well-preserved specimens, we evaluate sex differences and within-species variation using both qualitative and quantitative traits. We use these data to determine whether these specimens are morphologically similar to the species holotype KNM-BG 35250 (which shows some plastic deformation) and to compare Nacholapithecus with other Miocene hominoids and extant anthropoids to evaluate the distinctiveness of its femur. The new fossil evidence reaffirms previously reported descriptions of some distal femoral traits, namely the morphology of the patellar groove. However, results also show that relative femoral head size in Nacholapithecus is smaller, relative neck length is longer, and neck-shaft angle is lower than previously reported for KNM-BG 35250. These traits have a strong functional signal related to the hip joint kinematics, suggesting that the morphology of the proximal femur in Nacholapithecus might be functionally related to quadrupedal-like behaviors instead of more derived antipronograde locomotor modes. Results further demonstrate that other African Miocene apes (with the exception of Turkanapithecus kalakolensis) generally fall within the Nacholapithecus range of variation, whose overall femoral shape resembles that of Ekembo spp. and Equatorius africanus. Our results accord with the previously inferred locomotor repertoire of Nacholapithecus, indicating a combination of generalized arboreal quadrupedalism combined with other antipronograde behaviors (e.g., vertical climbing)

    A Case of Self-Limiting Crescentic Immunoglobulin A Glomerulonephritis Associated with Sternoclavicular Arthritis

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    Immunoglobulin (Ig) A glomerulonephritis (GN) is a heterogeneous disease affected by various factors. Genetic and other factors “hit” DNA, causing IgA malformation and ultimately glomerular injury. We describe a rare case of crescentic IgA GN with sternoclavicular (SC) arthritis in a 75-year-old woman. Despite active IgA GN with cellular crescents, the patient achieved remission of IgA GN without glucocorticoid therapy after remission of SC arthritis was achieved. Considering the patient’s clinical course, this case suggested a relationship between IgA GN and SC arthritis

    Intracrine activity involving NAD-dependent circadian steroidogenic activity governs age-associated meibomian gland dysfunction

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    新たなイントラクライン機構を用いた加齢性眼疾患治療へ --眼局所のホルモンの加齢変化とサーカディアンリズムが鍵--. 京都大学プレスリリース. 2022-02-14.Canonically, hormones are produced in the endocrine organs and delivered to target tissues. However, for steroids, the concept of tissue intracrinology, whereby hormones are produced in the tissues where they exert their effect without release into circulation, has been proposed, but its role in physiology/disease remains unclear. The meibomian glands in the eyelids produce oil to prevent tear evaporation, which reduces with aging. Here, we demonstrate that (re)activation of local intracrine activity through nicotinamide adenine dinucleotide (NAD+)-dependent circadian 3β-hydroxyl-steroid dehydrogenase (3β-HSD) activity ameliorates age-associated meibomian gland dysfunction and accompanying evaporative dry eye disease. Genetic ablation of 3β-HSD nullified local steroidogenesis and led to atrophy of the meibomian gland. Conversely, reactivation of 3β-HSD activity by boosting its coenzyme NAD+ availability improved glandular cell proliferation and alleviated the dry eye disease phenotype. Both women and men express 3β-HSD in the meibomian gland. Enhancing local steroidogenesis may help combat age-associated meibomian gland dysfunction

    Effects of exercise training on gingival oxidative stress in obese rats

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    Objective: The purpose of the present study was to investigate the effects of exercise training on serum reactive oxygen species (ROS) level and gingival oxidative stress in obese rats fed a high-fat diet. Design: Rats were divided into three groups (n = 14/group): one control group (fed a regular diet) and two experimental groups (fed a high-fat diet with and without exercise training [treadmill: 5 days/week]). The rats were sacrificed at 4 or 8 weeks. The level of serum reactive oxidative metabolites (ROM) was measured as an indicator of circulating ROS. The level of 8-hydroxydeoxyguanosine (8-OHdG) and reduced-form glutathione (GSH)/oxidised-form glutathione (GSSG) ratio were determined to evaluate gingival oxidative stress. Results: The obese rats fed a high-fat diet without exercise training showed higher serum ROM levels [Carratelli Units (CARR U)] (mean +/- SD; 413 +/- 64) than the control (333 +/- 12) at 4 weeks (p = 0.023). Such a condition resulted in higher 8-OHdG levels (ng/mg mtDNA) (0.97 +/- 0.18) (p < 0.05) and a lower GSH/GSSG ratio (17.0 +/- 3.1) (p < 0.05) in gingival tissues, compared to the control (0.55 +/- 0.13 for 8-OHdG and 23.6 +/- 5.8 for GSH/GSSG ratio) at 8 weeks. In addition, the obese rats fed a high-fat diet with exercise training showed lower serum ROM (623 +/- 103) (p<0.001) and gingival 8-OHdG levels (0.69 +/- 0.17) (p = 0.012) than those without exercise training (1105 95 for ROM and 0.55 +/- 0.13 for 8-OHdG) at 8 weeks. Conclusions: Obesity prevention by exercise training may effectively suppress gingival oxidative stress by decreasing serum ROS in rats
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