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991.
Post-injury regeneration in rat sciatic nerve facilitated by neurotrophic factors secreted by amniotic fluid mesenchymal stem cells. 总被引:1,自引:0,他引:1
Hung-Chuan Pan Fu-Chou Cheng Chun-Jung Chen Shu-Zhen Lai Chi-Wen Lee Dar-Yu Yang Ming-Hong Chang Shu-Peng Ho 《Journal of clinical neuroscience》2007,14(11):1089-1098
Amniotic fluid mesenchymal stem cells have the ability to secrete neurotrophic factors that are able to promote neuron survival in vitro. The purpose of this study was to evaluate the effects of neurotrophic factors secreted by rat amniotic fluid mesenchymal stem cells on regeneration of sciatic nerve after crush injury. Fifty Sprague-Dawley rats weighing 250-300 g were used. The left sciatic nerve was crushed with a vessel clamp. Rat amniotic fluid mesenchymal stem cells embedded in fibrin glue were delivered to the injured nerve. Enzyme-linked immunosorbent assay (ELISA) and immunocytochemistry were used to detect neurotrophic factors secreted by the amniotic fluid mesenchymal stem cells. Nerve regeneration was assessed by motor function, electrophysiology, histology, and immunocytochemistry studies. Positive CD29/44, and negative CD11b/45, as well as high levels of expression of brain-derived neurotrophic factor, glia cell line-derived neurotrophic factor, ciliary neurotrophic factor (CNTF), nerve growth factor, and neurotrophin-3 (NT-3) were demonstrated in amniotic fluid mesenchymal stem cells. Motor function recovery, the compound muscle action potential, and nerve conduction latency showed significant improvement in rats treated with amniotic fluid mesenchymal stem cells. ELISA measurement in retrieved nerves displayed statistically significant elevation of CNTF and NT-3. The immunocytochemical studies demonstrated positive staining for NT-3 and CNTF in transplanted cells. The histology and immunocytochemistry studies revealed less fibrosis and a high level of expression of S-100 and glial fibrillary acid protein at the crush site. Rat amniotic fluid mesenchymal stem cells may facilitate regeneration in the sciatic nerve after crush injury. The increased nerve regeneration found in this study may be due to the neurotrophic factors secreted by amniotic fluid mesenchymal stem cells. 相似文献
992.
Effects of gastric bypass procedures on bone mineral density,calcium, parathyroid hormone,and vitamin d 总被引:2,自引:0,他引:2
Jason M. Johnson James W. Maher Isaac Samuel Deborah Heitshusen Cornelius Doherty Robert W. Downs 《Journal of gastrointestinal surgery》2005,9(8):1106-1111
Weight loss after gastric bypass procedures has been well studied, but the long-term metabolic sequelae are not known. Data
on bone mineral density (BMD), calcium, parathyroid hormone, and vitamin D were collected preoperatively and at yearly intervals
after gastric bypass procedures. A total of 230 patients underwent preoperative BMD scans. Fifteen patients were osteopenic
preoperatively, and three patients subsequently developed osteopenia postoperatively within the first year. No patient had
or developed osteoporosis. At 1 year, total forearm BMD decreased by 0.55% (n = 91; P = .03) and radius BMD had increased overall by 1.85% (n = 23; P = .008); both total hip and lumbar spine BMD decreased by
9.27% (n = 22; P < .001) and 4.53% (n = 31; P < .001), respectively. By the second postoperative year, BMD in the total forearm had decreased an additional 3.62% (n =
14; P<.001), whereas radius BMD remained unchanged. Although total hip and lumbar spine BMD significantly decreased at 1 year,
by year 2 both total hip and lumbar spine BMD only slightly decreased and were not significantly different from before the
operation. Serum calcium decreased from 9.8 mg/dL to 9.2 during the first year (not significant [NS]) and then to 8.8 (NS)
by the second year. Parathyroid hormone increased from 59.7 pg/mL (nl 10-65 pg/mL) preoperatively to 63.1 during year 1 (NS)
and continued to increase to 64.7 by year 2 (NS). No difference was noted among levels of 25-hydroxy vitamin D preoperatively
(25.2 ng/mL; nl 10-65 ng/mL), at 1 year (34.4), and at 2 years (35.4). Our data indicate that bone loss is highest in the
first year after gastric bypass with stabilization, and that, in some cases, there is an increase in bone density after the
first year.
Presented at the Forty-Sixth Annual Meeting of The Society for Surgery of the Alimentary Tract, Chicago, Illinois, May 14–18,
2005 (oral presentation). 相似文献
993.
Exogenous advanced glycosylation end products induce diabetes-like vascular dysfunction in normal rats: a factor in diabetic retinopathy 总被引:2,自引:0,他引:2
Xun Xu Zhiping Li Dawei Luo Yufeng Huang Jianfeng Zhu Xiaojue Wang Honghui Hu C. Patrick 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2003,241(1):56-62
BACKGROUND. Diabetic retinopathy has been shown to be directly associated with the degree and duration of hyperglycemia, and advanced glycosylation end products (AGEs) have been implicated in this pathological process. The purpose of the experiments reported here was to study the effect of AGE deposition on retinal vascular damage which leads to diabetic retinopathy. METHODS. Intravenous injection of exogenous AGEs was used to treat wild-type non-diabetic Sprague-Dawley rats. One of the two retinal slides from each animal was treated using immunohistochemical staining to label retinal vascular AGE deposition, the other H&E staining for counting of capillary pericytes. The results were compared with the findings in untreated wild-type and diabetic controls and in rats treated with unmodified rat serum albumin (RSA). RESULTS. After 2 weeks of continuous treatment, AGEs were identified in the retinal vascular tissue of the AGE-RSA-injected group. The average number of retinal capillary pericytes per 10x100 microscope power field was 4.313+/-0.34 (mean +/- SD) in the AGE-RSA-injected group, compared with 5.798+/-0.481 in the control group ( P<0.01). CONCLUSION. These experiments demonstrate that AGEs, independent of other metabolic factors, can induce vascular change resembling that of diabetic retinopathy. 相似文献
994.
Christian Lee Norman Tinanoff Glenn Minah Elaine Romberg 《Journal of public health dentistry》2008,68(1):57-60
OBJECTIVES: Visible plaque on the maxillary anterior teeth of young children has been identified as a risk indicator for early childhood caries. The present study examined whether this plaque is related to the colonization of children's teeth with Mutans streptococci (MS) or toothbrushing frequency. METHODS: Thirty-nine children, aged 12 to 36 months, had plaque scores, and plaque samples were taken from the labial surfaces of the maxillary incisors at baseline and repeated 3 days after suspended oral hygiene (plaque regrowth). RESULTS: A positive correlation was found between the baseline percent MS and regrowth plaque score and between baseline and regrowth plaque scores. Plaque scores of those that brushed zero to one time a day were not different from those who brushed two or more times a day. CONCLUSIONS: This study suggests that the presence of plaque on the anterior teeth of young children is consistent and related to MS colonization. 相似文献
995.
Gardenia C. G. Militão Daniel P. Bezerra Claudia Pessoa Manoel Odorico de Moraes Flavio A. F. da Ponte Mary Anne S. Lima Edilberto R. Silveira Letícia V. Costa-Lotufo 《Journal of natural medicines》2007,61(2):196-199
The purpose of this study was to investigate the antiproliferative activity of 2,3,9-trimethoxypterocarpan, a known pterocarpan
with cytotoxic activity against many tumor cell lines, in a panel of four leukemia cell lines (HL-60, Molt-4, Jurkat, and
K562) and on human peripheral blood mononuclear cells (PBMC). The pterocarpan showed IC50 ranging from 0.1 to 0.5 μg/ml at leukemic cells after 72 h of incubation, with K562 being the most resistant cell line. This
compound seemed to be selective to tumor cell lines, since at a concentration of 10 μg/ml after 72 h, it only reduced 19%
of viable peripheral mononuclear cells. 相似文献
996.
A high molecular weight arabinogalactan protein (AGP) from the pressed juice of Echinacea purpurea, known to exhibit immunomodulatory properties in vitro, was characterized. Alkaline hydrolysis was carried out, leading to
degradation of the protein core and to carbohydrate moieties linked to the amino acid responsible for binding. Gel permeation
chromatography of these AG subunits gave one peak with a molecular weight of 30 × 103 Da. Hydroxyproline (42.9% w/w) was detected as the dominant amino acid after alkaline hydrolysis and was thus identified as
the major amino acid responsible for the binding between the protein and the AG subunits via an O-glycosidic linkage. Large
amounts of glutamine/glutamic acid (24.5% w/w) and asparagine/aspartic acid (17.3% w/w) were also found. Polyclonal antibodies
raised against the intact AGP were shown to bind to the AG subunits too, indicating that the epitopes responsible for such
interactions are localized in the polysaccharide moiety of the AGP. 相似文献
997.
998.
Marco Frattini Enrico Vaienti Giovanni Soncini Francesco Pogliacomi 《Musculoskeletal surgery》2009,93(3):109-114
Tibial plateau fractures are complex injuries which, if not adequately treated, can lead to invalidating sequelae. They constitute
on average about 1% of all fractures, and up to 8% in patients over 65 years, and can be caused by both high- and low-energy
trauma. Unlike in younger subjects, treatment of tibial plateau fractures in the elderly is not univocal and depends on the
patient’s functional needs, bone quality and systemic comorbidities. In this retrospective study, 49 patients with a mean
age of 72 years, who underwent surgical treatment of a tibial plateau fracture, were assessed by the Rasmussen’s clinical
and radiological grading systems. Clinical and radiographic outcomes were satisfactory in 75.5 and 59.1% of cases, respectively.
Data were also analyzed, in terms of fracture type, age and gender, to detect any statistically significant correlation between
these parameters and clinical and radiographic outcomes. 相似文献
999.
Hyung Bin Park Mihee Koh Se Hyun Cho Brian Hutchinson Bonghee Lee 《Journal of orthopaedic research》2005,23(6):1419-1424
The anterior cruciate ligament (ACL) serves as the primary restraint to anterior tibial translation. In addition to this biomechanical function, the ACL appears to have a function in neuromuscular control. This hypothesis was formulated after the discovery of mechanoreceptors within the ACL. The full somatosensory pathway from the ACL to the cerebrum has yet to be elucidated. In order to map this sensory pathway, we conducted a viral trans-synaptic tracing experiment using the neurotropic pseudorabies virus (PRV). The pseudorabies virus was injected into the ACL of rats and allowed to replicate and spread trans-synaptically for 6-7 days. The brain and spinal cord of each sacrificed rat was then removed and processed immunohistochemically to detect the presence of PRV. PRV-immunoreactive neurons were found to be localized in several different regions from the spinal cord to the cerebrum. Four nuclei in the reticular formation of the brain stem demonstrated strong positive labeling: the mesencephalic reticular nucleus, magnocellular reticular nucleus, paragigantocellular reticular nucleus, and gigantocellular reticular nucleus. This finding suggests that the nerve endings of the rat ACL project into the cerebrum and that the reticular formation may play an important role in the afferent pathway of those nerve endings. 相似文献
1000.
Eung Y. Kim Dong-Hyun Kim Eunhye Yoo Hae-Jeong Park Xavier Golay Seung-Koo Lee Dong J. Kim Jinna Kim Dong I. Kim 《International journal of developmental neuroscience》2007,25(6):409-414
Previous studies have shown that maturation of the white matter in terms of its relative signal intensity changes on MRI is almost complete at 2-3 years of age. We hypothesized that quantitative analysis may show maturation of the white matter during childhood and adolescence. In the present study we performed multi-echo T2 relaxometry in 33 healthy subjects (girls, 15; boys, 18) aged 3-15 years. T2 relaxation times of the genu and splenium were measured. In healthy subjects, the T2 relaxation times were significantly correlated with age in both girls (r=0.611, p=.016) and boys (r=0.721, p=.001) in the splenium, but not in the genu (p>.05). To further confirm genu-to-splenium signal intensity ratio changes, a total of 389 brain MRIs were retrospectively selected from the patients who had normal results (189 girls/women, 200 boys/men; age range, 3-20 years). The genu-to-splenium signal intensity ratio was obtained from the T2-weighted images. In patients with normal MRI, the genu-to-splenium signal intensity ratio was significantly decreased with age (p<.001) by 16 years. The T2 relaxation times gradually increase in the splenium during childhood and adolescence, suggestive of maturation. 相似文献