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41.
生长板软骨细胞促进骨髓基质干细胞血管内皮生长因子的表达 总被引:1,自引:1,他引:0
目的观察骨髓基质干细胞(BMSCs)在生长板软骨细胞旁分泌作用下血管内皮生长因子(VEGF)的表达规律及其与成骨分化的相关性。方法大鼠BMSCs与生长板软骨细胞进行间接共培养,培养终末期做细胞化学染色,定量测定碱性磷酸酶(ALP)活性,用RT-PCR方法半定量检测VEGFmRNA的表达。结果生长板软骨细胞持续高表达VEGF。BMSCs随共培养时间的延长,ALP活性升高,BMSCs的VEGF的表达也逐渐增强。培养液加入两种分泌型VEGF中和抗体后,VEGF表达趋势不变,ALP活性仍为升高趋势,也不影响培养终末期钙化结节的形成。培养终末期BMSCs的CD31和CD34均阴性。结论BMSCs成骨分化过程中VEGF的表达符合成骨细胞分化基因的表达规律,与成骨细胞特征性基因的表达趋势一致,体外条件共培养条件下,中和VEGF后并不能阻碍BMSCs的成骨分化。 相似文献
42.
The insulin-like growth factor-II/mannose-6-phosphate receptor: structure, distribution and function in the central nervous system 总被引:4,自引:0,他引:4
The insulin-like growth factor-II/mannose-6-phosphate (IGF-II/M6P) receptor is a multifunctional single transmembrane glycoprotein which, along with the cation-dependent M6P (CD-M6P) receptor, mediates the trafficking of M6P-containing lysosomal enzymes from the trans-Golgi network (TGN) to lysosomes. Cell surface IGF-II/M6P receptors also function in the degradation of the non-glycosylated IGF-II polypeptide hormone, as well as in the capture and activation/degradation of extracellular M6P-bearing ligands. In recent years, the multifaceted role of the receptor has become apparent, as several lines of evidence have indicated that in addition to its role in lysosomal enzyme trafficking, clearance and/or activation of a variety of growth factors and endocytosis-mediated degradation of IGF-II, the IGF-II/M6P receptor may also mediate transmembrane signal transduction in response to IGF-II binding under certain conditions. However, very little is known about the physiological significance of the receptor in the function of the central nervous system (CNS). This review aims to delineate what is currently known about IGF-II/M6P receptor structure, its ligand binding properties and role in lysosomal enzyme transport. It also summarizes the recent data regarding the role of the receptor in the CNS, including its distribution, possible importance for normal and activity-dependent functioning as well as its implications in neurodegenerative disorders such as Alzheimer's disease (AD). 相似文献
43.
G
NÜL
CAL MERIH BERBEROGLU SEMA AKURN NIHAL MEMOGLU AYDAN KNCOGULLARI 《Pediatrics international》1995,37(1):7-11
A total of 54 previously untreated patients (15 girls, 39 boys) with poor growth due to idiopathic growth hormone deficiency (IGHD) were treated with human growth hormone (hGH), continuously up to 4 years. All of the patients had a peak hGH level which was below 10 ng/mL after at least two pharmacological tests and/or blunted physiologic hGH secretion, and their height was below ?2.5 s.d. for age and gender. After the 1st year of therapy, height velocity (HV) increased significantly when compared with baseline (from 3.18 ±0.76 cm/year to 9.17±1.03 cm/year; P <0.001), declined during the 2nd year and then remained significantly higher than pretreatment HV. When considering improvement in height expressed by height standard deviation score (SDS), during the therapy all of the patients showed a significant gain ± 1.72±1.09 (from ?4.11±0.61 to ?2.21±0.48). The height values were significantly higher than pretreatment, but remained below ?2 s.d. after 4 years of hGH therapy in our patients. Increased height velocity has been sustained, but height improvement after therapy was inversely correlated to height SDS for chronological age of patients at the start of therapy. In conclusion post-treatment height has been shown to be related to height deficit at the beginning of therapy. Therapy was well tolerated with no local or systemic adverse effects or acceleration of bone age. 相似文献
44.
目的:探讨急性肾功能衰竭的治疗。方法:复习有关急性肾功能衰竭的治疗文献,作一总结。结果:使用人工合成三肽序列(RGD)的多肽、生长因子、心房利钠因子和人工肾小管治疗急性肾功能衰竭都取得了较好的疗效。结论:这些新的治疗可望改善急性肾衰的预后和降低死亡率。 相似文献
45.
Deformation due to growth disturbance after epiphyseal fractures around the knee may involve more than the primarily injured
epiphysis, as spontaneous corrective growth of the opposite epiphyseal plate can take place in an attempt to maintain overall
alignment of the leg. As a result, there will be an inclination in the knee joint line if corrective osteotomy is only performed
for the primary angulation. We report two cases of this complex deformity in which corrective osteotomies of both the distal
femur and the proximal tibia were performed, resulting in correct alignment of the overall leg axis and knee joint axis.
Received: 25 May 1996 Accepted: 20 November 1996 相似文献
46.
目的:研究面神经撞击伤后面神经核内生长相关蛋白(GAP-43)的变化及高压氧(HBO)治疗的影响。方法:利用BIM-Ⅱ型生物撞击机致家兔右侧面神经干损伤,应用SP免疫组化染色法观察损伤后1、3、7、14和21天(分别用HBO治疗及不用HBO为对照)面神经核内GAP-43的变化,并用电镜观察面神经干超微结构变化。结果:面神经损伤第1天,伤侧面神经核区GAP-43样免疫反应性神经元(GLIN)开始增多,第14天其增多达到高峰,第21天逐渐下降。HBO治疗组伤后不同时期GLIN的增多明显高于对照组。伤后第21天,与对照组相比HBO组面神经干电镜观察可见较多的新生髓鞘。结论:HBO治疗可使伤后面神经核内GLIN增多,因而有助于面神经损伤后的修复与再生。 相似文献
47.
Demetrius Ellis Ron Shapiro Mark L. Jordan Velma P. Scantlebury Nisan Gilboa Laszlo Hopp Nancy Weichler Andreas G. Tzakis Richard L. Simmons 《Pediatric nephrology (Berlin, Germany)》1994,8(2):193-200
Clinical aspects of FK-506 or cyclosporine immunosuppression regimens were evaluated in 48 consecutive pediatric renal transplant recipients. Tapering and discontinuation of prednisone was employed only in children receiving FK-506 who experienced minor or no rejection episodes during the 1st posttransplant month. At 1 year follow-up, 17 of 22 (77%) of all children with functioning allografts were receiving no prednisone (n=13) or a mean dosage of 0.07 mg/kg per day (n=4). During the 1st month, acute cellular rejection was more common in the FK-506 group (0.58 vs. 0.21 rejections per patient,P<0.05) but allograft survival (92%) and renal function at 1 year posttransplant were identical in both groups. Compared with the cyclosporine regimen, FK-506 immunosuppression may be associated with a higher incidence of cytomegalovirus or reversible Epstein-Barr virus-induced lymphoproliferative disease. However, the FK-506 group had less hirsutism and gingival hypertrophy and required fewer antihypertensive medications independent of steroid use. Height standard deviation scores and weight-for-height index improved only in preadolescents receiving FK-506 but no prednisone (P<0.02 andP<0.05, respectively), but did not differ between children on FK-506 plus prednisone and those in the cyclosporine group. We conclude that the major advantages of FK-506 over cyclosporine immunosuppression are a reduced severity of hypertension and an improved cosmetic appearance which may improve long-term medical compliance. When used as monotherapy, FK-506 also shows promise in relieving the growth retardation associated with cyclosporine regimens that include prednisone. 相似文献
48.
Jeffrey V. Rosenfeld MS FRACS FRCS 《Journal of clinical neuroscience》1994,1(4):231-242
Great advances in neurobiology have resulted from 100 years of neural transplantation research. In the last 20 years, there has been a focus on using neural transplantation to repair the damaged central nervous system (CNS) utilising experimental animal models of various human neurodegenerative disease and CNS injury. Since 1985, there has been a rapid proliferation of adrenal medullary autograft transplantation to the caudate nucleus of humans with Parkinson's disease. However, this operation proved to be unsuccessful and was associated with unacceptable morbidity. Implantation of human fetal mesencephalon into patients with severe parkinsonism has supplanted the adrenal operation and has produced promising results, with some patients reported to improve markedly and some evidence of graft survival noted on positron emission tomography (PET). Host tissue recovery appears to be an important mechanism for this clinical improvement. The optimal technique is to use three to four fetuses from induced abortions of 6.5 to 8 weeks gestation, with multiple stereotactic implants into the putamen and caudate nucleus. Many biological questions still remain and the community remains troubled by the ethical problems of using fetal tissue obtained from abortions. This procedure is still experimental and should be restricted to a few centres with excellence in cell and molecular biology. A multicentre study is needed to more carefully evaluate CNS transplantation. Cloned neural precursor cells or immortalized embryonic cell lines genetically modified to manufacture selected growth factors or neurotransmitters may offer an alternative to the use of human fetal tissue. Much more experimental animal research is necessary before transplantation can be used to treat other CNS maladies. 相似文献
49.
M. -H. Smet F. de Zegher M. Vanderschueren-Lodeweyckx G. Marchal 《European radiology》1992,2(1):57-61
In this study, magnetic resonance imaging (MRI) was performed to document potentially present morphostructural abnormalities of the hypothalamopituitary region in seven infants (age 0–21 months) who presented very early in life with clinical and biochemical evidence of hypopituitarism. Four infants had associated congenital cerebro-facial malformations.The following anatomical abnormalities were identified in variable combinations: ectopic neurohypophysis absence of the pituitary stalk, extreme elongation of the pituitary stalk, aplasia of the anterior pituitary lobe and no identification of the hypothalamopituitary complex.MRI proved to be very sensitive in the identification of structural malformations of the hypothalamopituitary region in infants with or without cerebro-facial malformations. AllhwuLll the magnetic resonance image does not appear to be a good predictor of endocrine dysfunction, it provides us more insight into the precise aetiology of this disorder and may be therefore of diagnostic, prognostic and therapeutic importance. 相似文献
50.
M. Kneissel P. Roschger W. Steiner D. Schamall G. Kalchhauser A. Boyde M. Teschler-Nicola 《Calcified tissue international》1997,61(2):95-100
There is abundant data on cancellous bone in the aging human spine, but little relating to the growing vertebral cancellous
bone in childhood and adolescence. The purpose of this study was to map vertebral cancellous bone in a growth and age series
of historic skeletal samples and to make comparisons with data published on recent material. Lumbar vertebral bodies were
collected from 65 skeletons (0–60 years) from a medieval Nubian population. Ethnohistoric information was collected to interpret
conditions that might have influenced bone structure and metabolism. The cancellous bone was studied three dimensionally,
using stereophotography and scanning electron microscopy and morphometrically by performing a semiautomatic structural analysis
on digitized backscattered electron images of polymethacrylate-embedded material. The cancellous bone structure in the children
consisted mainly of a densely packed, uniform network of small rodlike trabeculae. The greatest bone volume fraction with
small, more platelike trabeculae was observed during adolescence. In young adults, larger platelike trabeculae were present
in the central zone and smaller trabeculae in the superior and inferior zones, as described for modern skeletal material.
Structural changes associated with aging were observed much sooner than in modern man. By the estimated age of approximately
50–60 years, the predominant architectural elements were slender rarified rods in both sexes. The ethnohistorical data suggest
that this was essentially a black African population of physically active peasants, not likely to suffer Vitamin D insufficiency
or deficient calcium intake. Thus an earlier onset of the biological age changes in cancellous bone found in modern populations
was probably prevalent.
Received: 1 March 1996 / Accepted: 31 December 1996 相似文献