Smad5基因敲除小鼠听生理和耳蜗形态实验观察

目的观察Smad5基因敲除小鼠(Smad5+/-)听生理和耳蜗形态改变,探讨Smad5基因是否为一种新的听功能相关基因。方法双盲对照法对Smad5(+/-)和Smad5(+/+)小鼠进行听性脑干诱发电位(ABRs)的听阈检测和耳蜗毛细胞形态观察及毛细胞计数。结果ABR听阈Smad5(+/-)小鼠24周时为90.63±17.65dB(SPL),Smad5(+/+)小鼠为63±19.94dB(SPL),二者差异显著(P<0.01)。耳蜗基底膜铺片显示Smad5(+/-)小鼠内、外毛细胞缺失,其中在底回处尤其突出,Smad5(+/+)小鼠内、外毛细胞少量缺失。Smad5(+/-)与Smad5(+/+)小鼠外毛细胞计数差异有显著性意义(P<0.01),而内毛细胞计数差异无显著意义(P>0.05)。结论Smad5基因敲除导致小鼠中、重度听力下降,耳蜗基底膜毛细胞缺失,以外毛细胞为主。Smad5基因敲除导致毛细胞缺失是Smad5(+/-)小鼠听力损失的原因之一。推测Smad5基因可能是听功能相关基因。     

PIKfyve基因敲除对小鼠成熟免疫细胞分布与数量的影响

目的 建立PIKfyve基因全身与造血系统诱导性敲除小鼠模型,探索PIKfyve对免疫稳态的影响,为后续研究PIKfyve在造血系统中的功能提供基础。方法 将LoxP位点插入PIKfyve基因第六外显子两端,建立PIKfyve+/^flox小鼠,PIKfyve+/^flox小鼠与PIKfyve+/^flox小鼠互配得到PIKfyve^flox/^flox小鼠,PIKfyve^flox/^flox小鼠与UBC-Cre/ER^T2小鼠杂交得到PIKfyve+/^flox、UBC-Cre/ER^T2小鼠,再与PIKfyve^flox/^flox小鼠杂交即可得到PIKfyve^flox/^flox、UBC‐Cre/ER^T2小鼠,即为目的小鼠。经基因型鉴定与诱导后,利用实时荧光定量PCR与Weste...     

IL-22对ApoE基因敲除小鼠脂肪肝抑制作用的研究

目的：研究白介素-22（IL-22）对ApoE基因敲除小鼠肝脏的保护作用并探讨其作用机制。方法：选取24只ApoE基因敲除小鼠,随机分为IL-22组和生理盐水组,尾静脉注射IL-22,剂量0．25mg／kg,隔天给药一次,连续20次,观察肝功指标、损伤指标、血脂水平和病理变化的情况。结果：小鼠经IL-22处理后,其C反应蛋白（CRP）水平虽没有明显改变（P〉0．05）,但小鼠的血脂、ALT、AST、MAD水平以及肝指数显著降低（P〈0．05）,并且小鼠脂肪肝的病变程度也明显减轻。结论：IL-22能够降低ApoE基因敲除小鼠肝脏炎症指标并抑制脂肪肝发展。     

红细胞分化相关基因敲除小鼠对低剂量辐射损伤敏感性的研究

目的：构建红细胞分化相关基因（ EDAG）敲除小鼠并研究其对低剂量辐射损伤的敏感性。方法利用锌指核酸酶技术（ ZFNs）建立EDAG敲除小鼠模型;通过外周血细胞计数、骨髓细胞的DNA损伤和集落形成能力评价低剂量辐射损伤。对野生型及EDAG敲除小鼠进行剂量率为0．31 Gy／min的X线照射,1 min／d,连续照射7 d,小鼠累计照射剂量为2．17 Gy。在X线照射后第1、3、5、7天称重并进行血常规检测（n＝7）;照射后第3天分离小鼠骨髓细胞,利用免疫荧光实验检测DNA损伤标志物p-H2A．x的表达水平（ n＝3）;照射后第5天分离小鼠骨髓细胞,接种集落并于7 d后进行集落计数（ n＝3）。结果成功建立了EDAG敲除小鼠模型并在蛋白水平进行了敲除效果的鉴定;X线照射后第3天,与野生型相比,EDAG敲除小鼠白细胞明显减少,敲除小鼠骨髓细胞DNA损伤标志物p-H2A．x表达水平增加;X线照射7 d后骨髓细胞的集落形成能力降低。结论研究发现EDAG敲除小鼠对低剂量辐射诱导的损伤更加敏感,表现为血细胞数量减少,骨髓细胞成集落能力下降,DNA损伤增加。表明EDAG敲除小鼠作为一种对辐射高度敏感的动物模型,可作为低剂量辐射损伤生物学效应评价的有力工具。     

新生小鼠成骨细胞体外培养及其形态结构变化

成骨细胞是体内参与骨形成过程的主要细胞，为研究其在骨形成过程中的地位和作用，作者参照以往的方法加以改进，成功地从新生小鼠颅骨中分离、培养出了成骨细胞，并观察了其在体外培养过程中形态结构的变化，建立了体外研究骨形成、骨代谢的生物学模型，并为以后采用成骨...     

去泛素化酶Otulin基因心内膜敲除小鼠模型的构建及表型初步分析

目的 构建心内膜条件性敲除去泛素化酶Otulin基因小鼠模型,初步分析该模型小鼠的表型。方法 Cre?loxP重组技术构建心内膜条件性Otulin基因敲除小鼠模型;PCR技术明确Otulin基因敲除小鼠的基因型;统计分析敲除小鼠出生情况并观察其生长发育状态：超声监测小鼠心脏功能,全自动血液分析仪测定血液中细胞组分变化,苏木素?伊红（HE）染色评价小鼠各器官组织的病理改变。结果 心内膜特异性Otulin基因敲除小鼠模型成功构建;该条件性敲除小鼠可正常交配繁殖,子代基因型比例遵循孟德尔遗传定律;与同窝对照小鼠相比,该条件性敲除小鼠体型较小,体重减轻,脾明显肿大,血液中的炎性细胞数量显著增加,并且心脏组织三尖瓣缺损,心功能衰减。结论 成功构建心内膜特异性Otulin基因敲除小鼠模型,该模型小鼠心脏功能受损且有明显的炎症反应。     

Mxi1基因敲除小鼠遗传背景的转换研究

目的 对FVB/N品系Mxi1基因敲除(knock out,KO)(Mxi1-/-)小鼠进行遗传背景转换,为研究疾病发病机制提供更多种类的基因修饰小鼠.方法 将FVB/N品系杂合子小鼠(Mxi1+/-)与异性C57BL/6品系野生型(wild type,WT)小鼠(Mxi1+/+)杂交,获得杂合子F1代后将其与C57BL/6品系Mxi1+/+小鼠回交,再选择F2杂合子与C57BL/6品系Mxi1+/+小鼠回交,依此再回交8次后,子代互交.利用鼠尾DNA进行基因型鉴定及微卫星DNA(msDNA)检测,组织信使RNA(mRNA)和组织蛋白检测背景转换效率.结果 基因型鉴定为Mxi1-/-的互交子代小鼠msDNA检测结果与WT型C57BL/6小鼠一致,与FVB/N小鼠不同.PCR和Western印迹结果显示,随机选取的任意自交子代纯合子小鼠体内不表达Mxi1的mRNA和蛋白质,成功获得C57BL/6品系Mxi1-/-小鼠.结论 通过杂交-回交的方式成功获得的新品系Mxi1-/-小鼠能稳定地将突变基因传递给子代.这一成果为疾病动物模型的建立提供了更多的选择.     

Cerebrovascular occlusive complications in osteopetrosis major

Summary We report the case of a 16-year-old patient with osteopetrosis major, complaining of transient sensory and motor disturbances in the left upper limb and diziness on changing the position of his head. Selective angiography of the cerebral vessels showed severe narrowing of the internal carotid artery within the petrous carotid canal and in its supraclinoid portion. The cervical vertebral arteries showed multiple stenosis within the vertebral canal. These findings are explained by narrowing of the basal foramina by the osteopetrotic bone.     

Intermediate form of osteopetrosis with recessive inheritance

The clinical and radiographic features of the intermediate form of osteopetrosis in two sibs are presented in which the disorder appears to have been inherited as a recessive trait. Although this form of osteopetrosis has been poorly delineated, its recognition is practically important in order to give an accurate prognosis. This paper also presents an unusual complication of bilateral avascular necrosis of the femoral head in the younger sib. Radiographic changes of the femoral heads suggest those of Legg-Calvé-Perthes disease, though the possibility of avascular necrosis following unrecognized femoral neck fracture is not completely excluded.     

The detection of extramedullary hematopoiesis in a patient with osteopetrosis

^99mTc-HSA millimicrospheres were used to detect a site of extra medullary hematopoiesis in the chest of a patient with severe osteopetrosis, anemia, thrombocytopenia and splenomegaly causing renal complications. These problems led to the consideration of splenectomy which necessitated a search for other extra medullary hematopoietic sites.     

The detection of extramedullary hematopoiesis in a patient with osteopetrosis

99mTc-HSA millimicrospheres were used to detect a site of extra medullary hematopoiesis in the chest of a patient with severe osteopetrosis, anemia, thrombocytopenia and splenomegaly causing renal complications. These problems led to the consideration of splenectomy which necessitated a search for other extra medullary hematopoietic sites.     

The role of whole-body bone scintigraphy in a case of osteopetrosis

Male patient, 35 years old, with occasional mild intensity back pain. Lumbosacral spine radiography showed bone structure with increased density, diffusely and symmetrically, conferring to the vertebral bodies “bone-within-bone” aspect, suggesting osteopetrosis (OP). Whole-body bone scintigraphy showed abnormal uptake in proximal epiphysis of both the humeri, tibias and fibulas, distal epiphysis of the femurs and focal in the ribs suggesting old fractures. Conclusions: Nuclear Medicine may provide an important contribution as supporting diagnosis and extensive skeletal evaluation such as fractures and infection. Bone scintigraphy might also be used for baseline assessments, allowing longitudinal monitoring of the disease and patient follow-up.     

良恶性石骨症的临床及X线分析

目的：探讨良、恶性石骨症的临床及X线平片的特征性表现,提高对本病的鉴别诊断水平。方法：对12例良恶性石骨症患者的临床资料及X线平片表现进行回顾性分析,其中良性5例,恶性7例。结果：良性病变的临床特点为早期无症状,发病轻,进展慢。恶性型临床特点为发病早,进展快,进行性贫血,血小板减少,肝脾及淋巴结肿大。实验室检查主要指标...