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Because the development and activity of osteoclasts in bone remodeling is critically dependent on cell-cell and cell-matrix interactions, we used laser confocal microscopy to study the response of osteoclasts to lipopolysaccharide (LPS; 10 microg/ml), parathyroid hormone (PTH; 10(-8) M), and bisphosphonates (BPs; 1-25 microM clodronate or 0.1-2.5 microM risedronate) in cultured neonatal calvaria. Following treatment with LPS or PTH (<48 hr), osteopontin (OPN) and the alphavbeta3 integrin were found colocalized with the actin ring in the sealing zone of actively resorbing osteoclasts. In contrast, non-resorbing osteoclasts in BP-treated cultures showed morphological abnormalities, including retraction of pseudopods and vacuolization of cytoplasm. In the combined presence of LPS and BP, bone-resorbing osteoclasts were smaller and the sealing zone diffuse, reflecting reduced actin, OPN, and beta3 integrin staining. Depth analyses of calvaria showed that the area of resorbed bone was filled with proliferating osteoblastic cells that stained for alkaline phosphatase, collagen type I, and bone sialoprotein, regardless of the presence of BPs. These studies show that confocal microscopy of neonatal calvaria in culture can be used to assess the cytological relationships between osteoclasts and osteoblastic cells in response to agents that regulate bone remodeling in situ, avoiding systemic effects that can compromise in vivo studies and artifacts associated with studies of isolated osteoclasts.  相似文献   
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古河祥  周婷 《四川动物》2005,24(1):54-55
2001年, 广东惠东港口海龟国家级自然保护区管理局在 1000 多枚绿海龟的卵孵化过程中, 发现一例白化稚绿海龟 (见封3图版, 1)。现报道如下。白化稚绿海龟通体白色; 背甲、腹甲和四肢发育正常, 其量度见表 1。背甲卵圆形, 中央隆起,椎盾5枚, 肋盾8枚, 颈盾2枚, 左侧缘盾12枚,表1 白化稚绿海龟 (编重量体长背甲长背甲宽腹甲长腹甲宽15 2 53 38 40 9 35 3 25 01 23 36   人类白化病患者眼睛呈肉红色[1]。白化龟、白化鳖眼睛曾出现红色和黑色两种现象。该稚绿海龟白化个体因无眼睛, 故不知其…  相似文献   
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临夏盆地已知的大唇犀(Chilotherium属)共有3种,C.primigenius,C.anderssoni和C.wimani。其中,C.wimani是临夏盆地晚中新世三趾马动物群中的优势种类,在临夏盆地的柳树组中部和上部的各个化石地点均有出土,时代为晚中新世中期。该种下颌主要特征表现在联合部强烈地横向扩展和i2巨大且内刃上翻。本文所述标本为一件带畸形牙齿的C.wimani亚成年下颌,年龄约9岁,个体中等大小,其特征与C.anderssoni相差较大,而与C.wimani完全一致。其畸形之处表现在左、右两侧的p4为异常状态,并且在左侧还保留有dp4。左p4前后内外倒转,且下三角座仅为一锥形牙尖形态;右p4不仅内外反转,而且下三角座完全退失。这件标本从病因来看,左dp4的滞留很可能是左p4牙胚的不正常发育造成的,而左、右p4的畸形生长很可能是生物体遗传因素和营养不良共同造成的。C.wimani的数量庞大,种间和种内竞争都很激烈。牙齿的畸形影响了上下牙的咬合状况,在环境恶劣、竞争激烈的情况下,功能劣势是致命的。  相似文献   
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Characteristic cerebral palsy effects in the knee include a restricted joint range of motion and forcefully kept joint in a flexed position. To show whether the mechanics of activated spastic semitendinosus muscle are contributing to these effects, we tested the hypothesis that the muscle’s joint range of force exertion is narrow and force production capacity in flexed positions is high. The isometric semitendinosus forces of children with cerebral palsy (n = 7, mean (SD) = 7 years (8 months), GMFCS levels III–IV, 12 limbs tested) were measured intra-operatively as a function of knee angle, from flexion (120°) to full extension (0°). Peak force measured in the most flexed position was considered as the benchmark. However, peak force (mean (SD) = 112.4 N (54.3 N)) was measured either at intermediate or even full knee extension (three limbs) indicating no narrow joint range of force exertion. Lack of high force production capacity in flexed knee positions (e.g., at 120° negligible or below 22% of the peak force) was shown except for one limb. Therefore, our hypothesis was rejected for a vast majority of the limbs. These findings and those reported for spastic gracilis agree, indicating that the patients’ pathological joint condition must rely on a more complex mechanism than the mechanics of individual spastic muscles.  相似文献   
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BACKGROUND: Amniotic rupture sequence (ARS) is a disruption sequence presenting with fibrous bands, possibly emerging as a result of amniotic tear in the first trimester of gestation. Our comparative study aims to assess whether there is a difference in the clinical pattern of congenital limb and internal organ anomalies between ARS with body wall defect (ARS‐BWD) and ARS without BWD (ARS‐L). METHODS: Among 1,706,639 births recorded between 1998 and 2006, 50 infants with a diagnosis of ARS were reported to the Polish Registry of Congenital Malformations. The information on 3 infants was incomplete, thus only 47 cases were analyzed. These infants were classified into groups of ARS‐L (38 infants) and ARS‐BWD (9 infants). RESULTS: The ARS‐BWD cases were more frequently affected by various congenital defects (overall p < 0.0001), and in particular by urogenital malformations (p = 0.003). In both groups, limb reduction defects occurred in approximately 80% of cases; however, minor and distal limb defects (phalangeal or digital amputation, pseudosyndactyly, constriction rings) predominated in the ARS‐L group (p = 0.0008). The ARS‐L group also had a higher frequency of hand and upper limb involvement. CONCLUSIONS: This observation suggests that amniotic band adhesion in ARS‐L takes place at a later development stage. Although limited by a small sample size, our study contributes to the growing evidence that both ARS entities represent two nosologically distinct conditions. Birth Defects Research (Part A), 2009. © 2009 Wiley‐Liss, Inc.  相似文献   
58.
在哺乳动物中,位于Y染色体上的指导雄性性别分化的基因被命名为睾丸决定因子(Testis-determiningfactor,TDF)1990年6月分离获得的SRY基因(Sex-determiningregionoftheY)被认为是TDF基因最好的候选者[1-4]。SRY基因为单拷贝,位于Y染色体短臂末端1A1A区,靠近假常染色体配对区(PAPR)的交界处,其部分顺序编码80个保守性氨基酸组成的多肽。本实验使用与SRY基因相应的引物,利用PCR技术以一例性反转畸形病人的基因组DNA为模板分离SRY基因保守区顺序,并将特异扩增出的此SRY基因片段重组到质粒pUC12中,得到含有SRY基因片段的克隆。经测序表明其SRY基因保守顺序上有T→C(Ser→Pro)突变。SRY基因的存在及其突变可能是导致性反转畸形发病的原因。  相似文献   
59.
摘要 目的:探讨EarWell耳矫治器对新生儿耳廓畸形的效果及其预后不良影响因素。方法:选取我院2019年3月到2022年3月收治的60例(共78耳)耳廓畸形新生儿作为研究对象,依照患儿年龄进行分组,将年龄≤7 d的16例(21耳)患儿分为A组,8-14 d的21例(26耳)分为B组,15-28 d的23(31耳)分为C组,对所有患儿采取EarWell耳矫治器治疗,对比不同组别患儿新生儿耳廓畸形的治疗总有效率,并发症和矫治时间。通过复查随访评价患儿预后情况,将48例(60耳)预后良好的患儿分为预后良好组,将12例(18耳)预后不良的患儿分为预后不良组,对比两组患儿临床相关资料。最后,采用logistic回归分析分析EarWell耳矫治器对新生儿耳廓畸形治疗预后不良的影响因素。结果:三组患儿治疗总有效率差异显著,A组(100.00 %)高于B组(88.46 %)与C组(64.52 %)(P<0.05);A组患儿并发症发生率为14.29 %,B组为15.38 %,C组为19.35 %,组间对比有差异(P>0.05);预后良好组与预后不良组患儿性别、畸形部位对比无差异(P>0.05),预后良好组与预后不良组患儿年龄、耳廓畸形Max分型、外耳道闭锁分级以及容貌耳长差值对比差异显著(P<0.05);logistic回归分析结果显示,年龄、耳廓畸形Max分型为新生儿耳廓畸形治疗预后不良的独立影响因素(P<0.05)。结论:EarWell耳矫治器对于新生儿耳廓畸形矫治效果显著,并发症发生率较低,且年龄越小矫治效果越好。年龄、耳廓畸形Max分型为耳廓畸形新生儿的预后不良的独立影响因素,临床上针对此类患儿需采取一定预防措施,预防预后不良现象的发生。  相似文献   
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Gallium is a Group IIIa transitional element with therapeutic efficacy in the treatment of metabolic bone disorders. Previously described antiresorptive effects of gallium on osteoclasts are not sufficient to account for the full range of effects of gallium on bone structure and metabolism. We have recently shown that gallium nitrate inhibits osteocalcin gene expression and the synthesis of osteocalcin protein, an osteoblast-specific bone matrix protein that is though to serve as a signal to trigger osteoclastic resorption. Here we present evidence for an additional mechanism by which gallium may function to augment bone mass by altering matrix protein synthesis by osteoblastic and fibroblastic cells. Rat calvarial explants exposed to gallium nitrate for 48 h showed increased incorporation of 3H-proline into hydroxyproline and collagenase digestible protein. In addition, gallium treatment increased steady-state mRNA levels for fibronectin and type I procollagen chains in primary rat calvarial osteoblast-enriched cultures, the ROS 17/2.8 osteoblastic osteosarcoma line, and nontransformed human dermal fibroblasts. These findings suggest that the exposure of mesenchymally-derived cells to gallium results in an altered pattern of matrix protein synthesis that would favor increased bone formation.  相似文献   
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