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991.
Dermatoglyphic traits were studied in a sample of 834 subjects selected from a cohort of some 8,000 living Japanese men, under a long-term study of heart disease in Hawaii. All of them were born between 1900 and 1919. Among them, 100 subjects had had positive diagnosis of myocardial infarction (MI). The present study included comparisons between the MI patients and the remaining group of all digital dermal pattern types and ridge counts by digit, by hand, and by individual. The MI patients had significantly higher frequency of true whorls, double loops and less ulnar loops and tented arches. Total and absolute ridge counts were significantly higher (less than 0.05) in all digits in favor of the MI patients. Similar trends were observed in analyses by digit and by hand. These observations suggest an antenatal origin of certain types of coronary disease. 相似文献
992.
Hyoun Sook Kim Kyung Hee Rhee Byung‐Gyu Kim Dae Gyu Kim Mi Seul Park Hyun‐Jung Kim Sunghoon Kim Byung Woo Han 《Proteins》2013,81(10):1840-1846
Human cytosolic aspartyl‐tRNA synthetase (DRS) catalyzes the attachment of the amino acid aspartic acid to its cognate tRNA and it is a component of the multi‐tRNA synthetase complex (MSC) which has been known to be involved in unexpected signaling pathways. Here, we report the crystal structure of DRS at a resolution of 2.25 Å. DRS is a homodimer with a dimer interface of 3750.5 Å2 which comprises 16.6% of the monomeric surface area. Our structure reveals the C‐terminal end of the N‐helix which is considered as a unique addition in DRS, and its conformation further supports the switching model of the N‐helix for the transfer of tRNAAsp to elongation factor 1α. From our analyses of the crystal structure and post‐translational modification of DRS, we suggest that the phosphorylation of Ser146 provokes the separation of DRS from the MSC and provides the binding site for an interaction partner with unforeseen functions.Proteins 2013; 81:1840–1846. © 2013 Wiley Periodicals, Inc. 相似文献
993.
Yiming Xu Weilin Sang Yiming Zhong Song Xue Mengkai Yang Cong Wang Haiming Lu Renchun Huan Xinjie Mao Libo Zhu Chuanglong He Jinzhong Ma 《Cell proliferation》2021,54(12)
ObjectivesAseptic loosening (AL) is the most common reason of total hip arthroplasty (THA) failure and revision surgery. Osteolysis, caused by wear particles released from implant surfaces, has a vital role in AL. Although previous studies suggest that wear particles always lead to osteoblast programmed death in the process of AL, the specific mechanism remains incompletely understood and osteoblast ferroptosis maybe a new mechanism of AL.Materials and MethodsCoCrMo nanoparticles (CoNPs) were prepared to investigate the influence of ferroptosis in osteoblasts and calvaria resorption animal models. Periprosthetic osteolytic bone tissue was collected from patients who underwent AL after THA to verify osteoblast ferroptosis.ResultsOur study demonstrated that CoNPs induced significant ferroptosis in osteoblasts and particles induced osteolysis (PIO) animal models. Blocking ferroptosis with specific inhibitor Ferrostatin‐1 dramatically reduced particle‐induced ferroptosis in vitro. Moreover, in osteoblasts, CoNPs significantly downregulated the expression of Nrf2 (nuclear factor erythroid 2‐related factor 2), a core element in the antioxidant response. The overexpression of Nrf2 by siKeap1 or Nrf2 activator Oltipraz obviously upregulated antioxidant response elements (AREs) and suppressed ferroptosis in osteoblasts. Furthermore, in PIO animal models, the combined utilization of Ferrostatin‐1 and Oltipraz dramatically ameliorated ferroptosis and the severity of osteolysis.ConclusionsThese results indicate that CoNPs promote osteoblast ferroptosis by regulating the Nrf2‐ARE signalling pathway, which suggests a new mechanism underlying PIO and represents a potential therapeutic approach for AL.CoCrMo‐Nanoparticles induced peri‐implant osteolysis by promoting osteoblast ferroptosis via regulating Nrf2‐ARE signalling pathway. Blocking ferroptosis with Ferrostatin‐1 and Oltipraz significantly ameliorated osteolysis induced by implanted particles, which suggests a new mechanism underlying particle‐induced osteolysis and represents a potential therapeutic approach for aseptic loosening. 相似文献
994.
Transposition of anatomical structures along the anteroposterior axis has been a commonly used mechanism for changing body proportions during the course of evolutionary time. Earlier work (Gaunt, S.J., 1994. Conservation in the Hox code during morphological evolution. Int. J. Dev. Biol. 38, 549-552; Burke, A.C., Nelson, C.E., Morgan, B.A., Tabin, C., 1995. Hox genes and the evolution of vertebrate axial morphology. Development 121, 333-346) showed how transposition in mesodermal derivatives (vertebrae) could be attributed to transposition in the expression of Hox genes along the axial series of somites. We now show how transposition in the segmental arrangement of the spinal nerves can also be correlated with shifts in the expression domains of Hox genes. Specifically, we show how the expression domains of Hoxa-7, a-9 and a-10 in spinal ganglia correspond similarly in both mouse and chick with the positions of the brachial and lumbosacral plexuses, and that this is true even though the brachial plexus of chick is shifted posteriorly, relative to mouse, by seven segmental units. In spite of these marked species differences in the boundaries of Hoxa-7 expression, cis regulatory elements located up to 5 kb upstream of the chick Hoxa-7 gene showed much functional and structural conservation with those described in the mouse (Puschel, A.W., Balling, R., Gruss, P., 1991. Separate elements cause lineage restriction and specify boundaries of Hox-1.1 expression. Development 112, 279-287; Knittel, T., Kessel, M., Kim, M.H., Gruss, P., 1995. A conserved enhancer of the human and murine Hoxa-7 gene specifies the anterior boundary of expression during embryonal development. Development 121, 1077-1088). We also show that chick Hoxa-7 and a-10 expression domains spread forward into regions of somites that are initially negative for the expression of these genes. We discuss this as evidence that Hox expression in paraxial mesoderm spreads forward, as earlier found for neurectoderm and lateral plate mesoderm, in a process that occurs independently of cell movement. 相似文献
995.
Jeong-Woo Choi Juhong Min Won-Hong Lee Sang Back Lee 《Biotechnology and Bioprocess Engineering》1999,4(1):58-58
A mathematical model for a three phase fluidized bed bioreactor (TFBBR) was proposed to describe oxygen utilization rate,
biomass concentration and the removal efficiency of Chemical Oxygen Demand (COD) in wastewater treatment. The model consisted
of the biofilm model to describe the oxygen uptake rate and the hydraulic model to describe flow characteristics to cause
the oxygen distribution in the reactor. The biofilm model represented the oxygen uptake rate by individual bioparticle and
the hydrodynamics of fluids presented an axial dispersion flow with back mixing in the liquid phase and a plug flow in the
gas phase. The difference of settling velocity along the column height due to the distributions of size and number of bioparticle
was considered. The proposed model was able to predict the biomass concentration and the dissolved oxygen concentration along
the column height. The removal efficiency of COD was calculated based on the oxygen consumption amounts that were obtained
from the dissolved oxygen concentration. The predicted oxygen concentration by the proposed model agreed reasonably well with
experimental measurement in a TFBBR. The effects of various operating parameters on the oxygen concentration were simulated
based on the proposed model. The media size and media density affected the performance of a TFBBR. The dissolved oxygen concentration
was significantly affected by the superficial liquid velocity but the removal efficiency of COD was significantly affected
by the superficial gas velocity.
An erratum to this article can be found online at . 相似文献
996.
We investigated the effect of magnolol (5,5'-diallyl-2,2'-dihydroxybiphenyl), a marker compound isolated from the cortex of Magnolia officinalis, in non-obese type 2 diabetic Goto-Kakizaki (GK) rats. The rats were treated orally with magnolol (100 mg/kg body weight) once a day for 13 weeks. In magnolol-treated GK rats, fasting blood glucose and plasma insulin were significantly decreased, and the pancreatic islets also showed strong insulin antigen positivity. Urinary protein and creatinine clearance (Ccr) were significantly decreased. Pathological examination revealed the prevention of the glomeruli enlargement in magnolol-treated GK rats. The overproduction of renal sorbitol, advanced glycation endproducts (AGEs), type IV collagen, and TGF-beta1 mRNA were significantly reduced in magnolol-treated GK rats. Thus based on our findings, the use of magnolol could result in good blood glucose control and prevent or retard development of diabetic complications such as diabetic nephropathy. 相似文献
997.
998.
Wi-Sun Ryu Keun-Sik Hong Sang-Wuk Jeong Jung E. Park Beom Joon Kim Joon-Tae Kim Kyung Bok Lee Tai Hwan Park Sang-Soon Park Jong-Moo Park Kyusik Kang Yong-Jin Cho Hong-Kyun Park Byung-Chul Lee Kyung-Ho Yu Mi Sun Oh Soo Joo Lee Jae Guk Kim Jae-Kwan Cha Dae-Hyun Kim Jun Lee Moon-Ku Han Man Seok Park Kang-Ho Choi Juneyoung Lee Jeffrey L. Saver Eng H. Lo Hee-Joon Bae Dong-Eog Kim 《PLoS medicine》2022,19(2)
BackgroundPreclinical data suggest circadian variation in ischemic stroke progression, with more active cell death and infarct growth in rodent models with inactive phase (daytime) than active phase (nighttime) stroke onset. We aimed to examine the association of stroke onset time with presenting severity, early neurological deterioration (END), and long-term functional outcome in human ischemic stroke.Methods and findingsIn a Korean nationwide multicenter observational cohort study from May 2011 to July 2020, we assessed circadian effects on initial stroke severity (National Institutes of Health Stroke Scale [NIHSS] score at admission), END, and favorable functional outcome (3-month modified Rankin Scale [mRS] score 0 to 2 versus 3 to 6). We included 17,461 consecutive patients with witnessed ischemic stroke within 6 hours of onset. Stroke onset time was divided into 2 groups (day-onset [06:00 to 18:00] versus night-onset [18:00 to 06:00]) and into 6 groups by 4-hour intervals. We used mixed-effects ordered or logistic regression models while accounting for clustering by hospitals. Mean age was 66.9 (SD 13.4) years, and 6,900 (39.5%) were women. END occurred in 2,219 (12.7%) patients. After adjusting for covariates including age, sex, previous stroke, prestroke mRS score, admission NIHSS score, hypertension, diabetes, hyperlipidemia, smoking, atrial fibrillation, prestroke antiplatelet use, prestroke statin use, revascularization, season of stroke onset, and time from onset to hospital arrival, night-onset stroke was more prone to END (adjusted incidence 14.4% versus 12.8%, p = 0.006) and had a lower likelihood of favorable outcome (adjusted odds ratio, 0.88 [95% CI, 0.79 to 0.98]; p = 0.03) compared with day-onset stroke. When stroke onset times were grouped by 4-hour intervals, a monotonic gradient in presenting NIHSS score was noted, rising from a nadir in 06:00 to 10:00 to a peak in 02:00 to 06:00. The 18:00 to 22:00 and 22:00 to 02:00 onset stroke patients were more likely to experience END than the 06:00 to 10:00 onset stroke patients. At 3 months, there was a monotonic gradient in the rate of favorable functional outcome, falling from a peak at 06:00 to 10:00 to a nadir at 22:00 to 02:00. Study limitations include the lack of information on sleep disorders and patient work/activity schedules.ConclusionsNight-onset strokes, compared with day-onset strokes, are associated with higher presenting neurologic severity, more frequent END, and worse 3-month functional outcome. These findings suggest that circadian time of onset is an important additional variable for inclusion in epidemiologic natural history studies and in treatment trials of neuroprotective and reperfusion agents for acute ischemic stroke.Wi-Sun Ryu and colleagues investigate the association of stroke onset time with presenting severity, early neurological deterioration (END), and long-term functional outcome in ischemic stroke. 相似文献
999.
Mi‐Kyung Han Xiaoyuen Zhou Ctirad Uher Sung‐Jin Kim Mercouri G. Kanatzidis 《Liver Transplantation》2012,2(10):1218-1225
The effects of Cd‐doping on the thermoelectric properties of Sn1–xPbxTe are investigated and compared to the properties of the corresponding Sn1–xPbxTe solid solutions. The addition of Cd results in a reduction in the carrier concentration and changes in the physical properties, as well as in the conduction type of Sn1–xPbxTe. A significant increase in the power factor accompanied by a reduction in the thermal conductivity result in a higher figure of merit (ZT) for (Sn1–xPbx)0.97Cd0.03Te than that of undoped Sn1–xPbxTe. The maximum ZT (~0.7) values are observed for p‐type material with x = 0.36 at 560 K. Much higher values (ZT ~ 1.2 at 560 K for x = 0.73) are obtained on n‐type samples. 相似文献
1000.
Jun Seo Goo Yo Na Kim Kyung Mi Choi In Sik Hwang Ji Eun Kim Young Ju Lee Moon Hwa Kwak Sun Bo Shim Seung Wan Jee Chul Joo Lim Je Kyung Seong Dae Youn Hwang 《Clinical proteomics》2013,10(1):10