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991.
Jong-Il Choi Bum-Joon Kim Sung-Kon Ha Se-Hoon Kim Dong-Jun Lim Sang-Dae Kim 《Child's nervous system》2014,30(6):1011-1019
Purpose
The purpose of this study was to investigate efficient ways to diagnose and predict clinical outcomes for childhood traumatic brain injury.Methods
Hemorrhagic signal intensities in nine brain regions were observed using axial fluid-attenuated inversion recovery (FLAIR) and susceptibility-weighted imaging (SWI). After having divided the subjects into mild presentation (GCS 14–15) and moderate-to-severe presentation groups (GCS ≤13), we divided the patients into three subgroups: Subgroup I, hemorrhagic foci observed only on SWI and not on FLAIR; Subgroup II, hemorrhagic foci observed on both SWI and FLAIR in the same brain regions; and Subgroup III, any cases with additional foci on SWI in other brain regions. We investigated the clinical course and compared lesion numbers and distributions of hemorrhagic lesions on SWI among the subgroups.Results
Three clinical variables (hospitalization period in intensive care unit, total days of hospitalization, and outcome based on Pediatric Cerebral Performance Category Scale score) showed significant relevance to the three subgroups. Subgroup I showed the fewest lesions followed by Subgroups II and III, respectively. In all three subgroups, lesions were most abundant in cortical regions. Lesion in the thalamus, basal ganglia, corpus callosum, and brainstem was least in Subgroup I and gradually increased in Subgroups II and III. Such distinction was more significant in the moderate-to-severe group when compared with the mild group.Conclusions
In cases of pediatric traumatic brain injury, categorizing patients into one of the above three subgroups based on hemorrhagic lesions on SWI and FLAIR is a promising method for predicting patient’s clinical outcome. 相似文献992.
993.
Won Hee Lim Bo Liu Du Cheng Daniel J Hunter Zhendong Zhong Daniel M Ramos Bart O Williams Paul T Sharpe Claire Bardet Su‐jung Mah Jill A Helms 《Journal of bone and mineral research》2014,29(4):892-901
Odontoblasts, cementoblasts, ameloblasts, and osteoblasts all form mineralized tissues in the craniofacial complex, and all these cell types exhibit active Wnt signaling during postnatal life. We set out to understand the functions of this Wnt signaling, by evaluating the phenotypes of mice in which the essential Wnt chaperone protein, Wntless was eliminated. The deletion of Wls was restricted to cells expressing Osteocalcin (OCN), which in addition to osteoblasts includes odontoblasts, cementoblasts, and ameloblasts. Dentin, cementum, enamel, and bone all formed in OCN‐Cre;Wlsfl/fl mice but their homeostasis was dramatically affected. The most notable feature was a significant increase in dentin volume and density. We attribute this gain in dentin volume to a Wnt‐mediated misregulation of Runx2. Normally, Wnt signaling stimulates Runx2, which in turn inhibits dentin sialoprotein (DSP); this inhibition must be relieved for odontoblasts to differentiate. In OCN‐Cre;Wlsfl/fl mice, Wnt pathway activation is reduced and Runx2 levels decline. The Runx2‐mediated repression of DSP is relieved and odontoblast differentiation is accordingly enhanced. This study demonstrates the importance of Wnt signaling in the homeostasis of mineralized tissues of the craniofacial complex. © 2014 American Society for Bone and Mineral Research. 相似文献
994.
Teriparatide (PTH 1‐34) Treatment Increases Peripheral Hematopoietic Stem Cells in Postmenopausal Women 下载免费PDF全文
Elaine W Yu Ruchit Kumbhani Erica Siwila‐Sackman Michelle DeLelys Frederic I Preffer Benjamin Z Leder Joy Y Wu 《Journal of bone and mineral research》2014,29(6):1380-1386
Cells of the osteoblast lineage play an important role in regulating the hematopoietic stem cell (HSC) niche and early B‐cell development in animal models, perhaps via parathyroid hormone (PTH)‐dependent mechanisms. There are few human clinical studies investigating this phenomenon. We studied the impact of long‐term daily teriparatide (PTH 1‐34) treatment on cells of the hematopoietic lineage in postmenopausal women. Twenty‐three postmenopausal women at high risk of fracture received teriparatide 20 mcg sc daily for 24 months as part of a prospective longitudinal trial. Whole blood measurements were obtained at baseline, 3, 6, 12, and 18 months. Flow cytometry was performed to identify hematopoietic subpopulations, including HSCs (CD34+/CD45(moderate); ISHAGE protocol) and early transitional B cells (CD19+, CD27‐, IgD+, CD24[hi], CD38[hi]). Serial measurements of spine and hip bone mineral density (BMD) as well as serum P1NP, osteocalcin, and CTX were also performed. The average age of study subjects was 64 ± 5 years. We found that teriparatide treatment led to an early increase in circulating HSC number of 40% ± 14% (p = 0.004) by month 3, which persisted to month 18 before returning to near baseline by 24 months. There were no significant changes in transitional B cells or total B cells over the course of the study period. In addition, there were no differences in complete blood count profiles as quantified by standard automated flow cytometry. Interestingly, the peak increase in HSC number was inversely associated with increases in bone markers and spine BMD. Daily teriparatide treatment for osteoporosis increases circulating HSCs by 3 to 6 months in postmenopausal women. This may represent a proliferation of marrow HSCs or increased peripheral HSC mobilization. This clinical study establishes the importance of PTH in the regulation of the HSC niche within humans. © 2014 American Society for Bone and Mineral Research. 相似文献
995.
Introduction
Although numerous studies have demonstrated the relationship between maturation and lower extremity biomechanics during landing in team sport athletes, we are presently uninformed of any research that examined the single-legged drop landing biomechanics of gymnasts. The purpose of this study is to investigate the effects of the menarcheal age on the lower extremity biomechanics during a single-legged drop landing in female artistic elite gymnasts.Materials and methods
Twenty-two female artistic elite gymnasts, between 9 and 36 years of age, participated in this study. The participants were divided into two groups pre- (n = 11) and post- (n = 11) menarche and asked to perform a single-legged drop landing on top of a 30 cm platform and land on a force plate. The statistical analysis consisted of the multivariate analysis with the level of significance set at p < 0.05.Results
The post-menarche group showed a decrease in their maximum knee flexion angle and increase in their maximum knee abduction angle, maximum internal tibial rotation angle, maximum knee abduction moment, and hamstring-quadriceps muscle activity ratio compared with the pre-menarche group during the single-legged drop landing.Conclusions
The post-menarche group showed an increased noncontact anterior cruciate ligament injury risk, due to their greater knee loads, compared with the pre-menarche group. 相似文献996.
We hypothesized that triglyceride-raising apolipoprotein A5 (APOA5)-1131T > C may contribute to the increased risk of obesity associated with dietary intake in Korean premenopausal women whose minor allele frequency is higher than that in Western people. Genetically unrelated Korean premenopausal women (approximately 20-59 years, n = 1128) were genotyped for APOA5-1131T > C. Anthropometric, metabolic parameters and dietary intakes were analyzed. Odds ratios (ORs) for obesity risk (body mass index, ≥25.0 kg/m2) were calculated. Genotype distribution of APOA5-1131T > C of study subjects were like TT: 49.9%, TC: 40.8%, and CC: 9.3%. We found a significant interaction between APOA5-1131T > C and total energy intake (TEI) for obesity after adjusted for age, cigarette smoking, and alcohol consumption (P < .001). The risk of obesity in CC homozygotes compared with T carriers (TT + TC) was significantly increased, when the subjects consume higher TEI (≥2001 kcal/d (8372 kJ/d), median value of the population) (OR, 2.495; 95% confidence intervals, 1.325-4.696; P = .005), particularly, when they maintain negative balance between total energy expenditure and TEI (total energy expenditure/TEI, <1) (OR, 2.917; 95% confidence intervals, 1.451-5.864; P = .003). The contributions of APOA5-1131CC homozygotes to obesity risk in those who consume higher TEI were all significantly high regardless of percentage of energy intake from dietary macronutrients. Whereas, no significant association was observed in those who consume lower TEI (<2001 kcal/d). In addition, serum levels of triglyceride, high-density lipoprotein–cholesterol, and apolipoprotein A5 were associated with APOA5-1131T > C and TEI. These findings suggest that APOA5-1131CC homozygotes may influence the susceptibility of the individual to obesity, particularly, when they consume higher TEI, but the genetic effect may be attenuated, when people maintain low or adequate energy intake. 相似文献
997.
998.
W. S. Wong H. M. J. Lam Y. F. Chow P. P. Chen H. S. Lim Steven Wong R. Fielding 《Quality of life research》2014,23(8):2333-2341
Purpose
In the fear-avoidance model (FAM) of chronic pain, pain-related fear is one of the most prominent predictors of negative adjustment outcomes. While existing data point to the effects of anxiety sensitivity, pain hypervigilance, and pain catastrophizing on pain-related fear, the nature of their multivariate relationships remains unclear. This study explored the possible mediating role of pain hypervigilance in the relationship of anxiety sensitivity and pain catastrophizing with pain-related fear, and their effects on quality of life (QoL) outcomes within the FAM framework.Methods
A sample of 401 Chinese patients with chronic musculoskeletal pain completed the standardized measures assessing the FAM components and QoL. Structural equation modeling (SEM) was used to evaluate six hypothesized models.Results
Results of SEM showed adequate data-model fit [comparative fit indexes (CFIs) ranging from 0.92 to 0.94] on models which specified pain hypervigilance as mediator of anxiety sensitivity and pain catastrophizing with pain-related fear on two QoL outcomes (QoL-Physical and QoL-Mental). Results consistent with net suppression effects of pain catastrophizing on anxiety sensitivity were found in SEM when both anxiety sensitivity and pain catastrophizing were included in the same full model to predict QoL-Physical (CFI = 0.95; Sobel z = 8.06, p < 0.001) and QoL-Mental (CFI = 0.93; Sobel z = 8.31, p < 0.001).Conclusions
These cross-sectional analyses gave results consistent with pain hypervigilance, mediating the relationship of pain catastrophic cognition and anxiety sensitivity with pain-related fear. The net suppression effects of pain catastrophizing point to anxiety sensitivity, enhancing the effect of pain catastrophic cognition on pain hypervigilance. These findings elucidate how the interdependence of dispositional factors might influence pain adjustment and functioning. 相似文献999.
Raliny O. Santos Gabriela L. M. de Assunção Diogo M. B. de Medeiros Ícaro A. de Sousa Pinto Keizianny S. de Barros Bruno L. Soares Eunice André Elaine C. Gavioli Vanessa de Paula Soares‐Rachetti 《Basic & clinical pharmacology & toxicology》2014,114(2):181-187
Sibutramine is a serotonin and norepinephrine reuptake inhibitor indicated for the treatment of obesity. A pre‐clinical study showed that acute administration of sibutramine promoted anxiolytic‐ and panicolytic‐like effects in male rats. However, in clinical reports, sibutramine favoured the onset of panic attacks in women. In this study, the effect of sibutramine on experimental anxiety in females and the relevance of different oestrous cycle phases for this effect were analysed. In experiment 1, both male and female rats were submitted to acute intraperitoneal injection of sibutramine or vehicle 30 min. before testing in the elevated T‐maze (ETM) and in the open‐field test (OF). Females in the pro‐oestrus (P), oestrus (E), early dioestrus (ED) and late dioestrus (LD) phases were tested in the ETM and OF (experiment 2) or in the elevated plus‐maze (EPM) 30 min. after the injection of sibutramine. Sibutramine impaired the escape response in the ETM in both males and females. This effect was observed for P, E and ED, but not for LD females. Sibutramine altered neither the inhibitory avoidance in the ETM nor the behaviour of females in the EPM. Thus, sibutramine promoted a panicolytic‐like effect in female rats cycling at P, E and ED, but not in the LD phase and did not alter behaviours related to anxiety in both ETM and EPM. Considering that pre‐clinical studies aiming the screening of anxiolytic drugs employ male rodents, data here obtained reinforce the importance of better understanding the effects of drugs in females. 相似文献