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41.
目的:一些理论质疑富血小板血浆对骨前体细胞成骨分化的作用,本实验拟验证富血小板血浆对体外培养的人骨髓间充质干细胞成骨分化的抑制效应。方法:实验于2005-05/11在南方医科大学组织工程试验室(省级)完成。①实验方法:抽取6名健康志愿者髂前上棘骨髓5mL进行体外细胞培养扩增,静脉血10mL以二次离心法制得富血小板血浆。诱导骨髓间充质干细胞时富血小板血浆与骨髓间充质干细胞均来自同一个体。②碱性磷酸酶染色:取第4代骨髓间充质干细胞,分为两组:富血小板血浆组加入富血小板血浆使终浓度为100g/L,单纯血清培养组仅加入等量胎牛血清。培养后第7天进行碱性磷酸酶染色,阳性细胞为胞质中呈现黑色颗粒或块状沉淀。③矿化结节染色:取第4代骨髓间充质干细胞,分组同上。培养后第19天以0.1%茜素红-TrisHcl(pH8.3)37℃下放置30min,矿盐沉积染色阳性为红色。④Cbfa1基因表达:取第4代骨髓间充质干细胞,分组同上。培养后第3,7,12,16天RT-PCR法检测骨髓间充质干细胞Cbfa1基因的表达。⑤形态学观察:实验过程中使用相差显微镜观察各组细胞生长情况及形态学变化。结果:①骨髓间充质干细胞碱性磷酸酶染色结果:培养后第7天,富血小板血浆组碱性磷酸酶阳性细胞数量较单纯血清培养组明显减少,且阳性细胞内灰黑色颗粒也明显减少,为弱阳性。②骨髓间充质干细胞矿化结节染色结果:培养后第19天,单纯血清培养组可见细胞表面有较多的矿盐沉积,但未形成明显的矿化结节。富血小板血浆组细胞表面只有稀少的矿盐沉积。③骨髓间充质干细胞cbfa1mRNA的表达:培养后第3,7,12,16天,随着培养时间的延长单纯血清培养组与富血小板血浆组cbfa1基因表达量均逐渐增高,同一时间点两组间cbfa1基因的表达基本相似。④骨髓间充质干细胞形态学变化:富血小板血浆组骨髓间充质干细胞增殖旺盛,细胞达到单层汇合的时间较单纯血清培养组明显缩短。单纯血清培养组细胞在完全汇合后开始出现聚合现象(14~16d),但趋向性不明显,未完全形成团簇;富血小板血浆组细胞在完全汇合后未出现聚合现象,细胞密集生长。培养初期两组细胞以梭形为主,多角形细胞较少,培养至14~16d单纯血清培养组多角形细胞较富血小板血浆组增多。结论:富血小板血浆可抑制人骨髓间充质干细胞碱性磷酸酶的分泌与矿盐沉积,对人骨髓间充质干细胞成骨分化的直接效应是抑制其分化。 相似文献
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45.
Jonathan Q. Trinh Christopher N. Carender Qiang An Nicolas O. Noiseux Jesse E. Otero Timothy S. Brown 《The Journal of arthroplasty》2021,36(5):1520-1526
BackgroundResilience and depression may impact clinical outcomes following primary total joint arthroplasty (TJA). This study aimed to quantify baseline resilience and depression prevalence in patients undergoing primary TJA and evaluate their influence on patient-reported clinical outcomes.MethodsWe prospectively enrolled 98 patients undergoing primary TJA. Exclusion criteria included patients under 18 years of age, undergoing surgery for fracture, or who underwent additional surgery during the study period. Patients completed the Brief Resilience Scale to measure resilience, Patient Health Questionnaire-9 to measure depression, and Patient-Reported Outcomes Measurement Information System-10 to measure global physical and mental health preoperatively and 1 year postoperatively.ResultsPreoperatively, 22% and 15% of patients demonstrated major and mild depression, respectively. High resilience was identified in 34% of patients, normal resilience in 55%, and low resilience in 11%. Preoperative depression correlated with lower resilience, global physical health, and global mental health scores preoperatively as well as at 1 year after surgery (P < .001). Higher levels of preoperative resilience correlated with higher global physical and mental health scores preoperatively and at 1 year postoperatively (P < .001).ConclusionDepression symptoms are common among patients undergoing primary TJA and are associated with worse patient-reported outcomes. Patients with higher levels of resilience have higher global physical and mental health scores before and after TJA. Psychological traits and depression impact clinical outcomes following TJA. 相似文献
46.
Fauzi Mohammad Faizal Ahmad Gokozan Hamza Numan Elder Brad Puduvalli Vinay K. Pierson Christopher R. Otero José Javier Gurcan Metin N. 《Journal of neuro-oncology》2015,124(3):393-402
Journal of Neuro-Oncology - We present a computer aided diagnostic workflow focusing on two diagnostic branch points in neuropathology (intraoperative consultation and p53 status in tumor biopsy... 相似文献
47.
Stijn JB Van Weyenberg Sietze T Van Turenhout Maarten AJM Jacobs Gerd Bouma Chris JJ Mulder 《Digestive endoscopy》2012,24(4):247-254
Background and Aim: Little is known about the causes of overt obscure gastrointestinal bleeding (OGIB) in patients using anti‐thrombotic therapy. We aimed to describe video capsule endoscopy (VCE) findings and to identify factors associated with positive findings in these patients. Methods: We carried out a retrospective study of 56 patients who underwent VCE for evaluation of previous overt OGIB during anti‐thrombotic therapy. VCE studies were re‐evaluated by a gastroenterologist blinded to clinical details. Clinical data included in the multivariate analysis were sex, age, indication for and type of anti‐thrombotic therapy, hemodynamic instability on admission, type of blood loss, hemoglobin on admission, use of a proton pump inhibitor, NSAID use, time between bleeding episodes and VCE, and whether or not anti‐thrombotic therapy was resumed before the VCE study. Results: A probable cause for gastrointestinal bleeding was identified in 28 (50%) of the 56 studies. Angiodysplasia was found in 19 patients. Twenty‐two studies showed a possible cause in the small bowel. Multivariate logistic regression analysis showed that reinstitution of anti‐thrombotic therapy before VCE was carried out was the only independent predictor of positive VCE findings (OR: 8.61, 95% CI: 1.20–60.42, P = 0.032). Conclusions: Small intestinal angiodysplasia was the most common cause for overt OGIB. Reinstitution of withdrawn anti‐thrombotic drugs before the VCE examination was carried out was associated with positive VCE findings in multivariate analysis. 相似文献
48.
Restriction of cell lysis by homologous complement: II. Protection of erythrocytes against lysis by newly activated complement 总被引:1,自引:0,他引:1
Our previous work revealed that homologous complement (C) was ineffective in lysing antibody-sensitized erythrocytes (EA) even at high concentrations. It was also shown that activation of complement on homologous EA resulted in the binding of C9 and the formation of EA bearing complement proteins C1 through C9 (EAC1-9), yet few hemolytic sites were formed. Instead, as shown here, the formation of homologous EAC1-9 caused the cells to become resistant to lysis even by heterologous complement during a second incubation. In contrast, when homologous EAC1-8 were produced by incubating EA with C9-depleted serum, such intermediates were not protected against lysis by heterologous complement during a second incubation. Furthermore, homologous C9 on EAC1-9 was able to reduce the hemolytic efficiency of heterologous complement without blocking C activation and the formation of new C5b-9 complexes. Protection was not modified when homologous EAC1-9 were produced in one step, by incubation of EA with serum, or sequentially by adding C9 to EAC1-8. The minimum number of 9-sites required to confer a protective effect on EAC1-9 was less than 200 per cell. Thus, in addition to its known effect in heterologous cell killing, homologous C9 is capable of protecting homologous cells against inadvertent complement lysis. 相似文献
49.
Juan-Manuel Fernandez-Somoza Manuel Ginarte Esteban Otero Santiago Tom Carlos Soutullo Aarn Martínez-Ulloa Arturo Gonzalez-Quintela 《Medicine》2021,100(22)
Terry nails and Lindsay nails are similar forms of proximal apparent leukonychia (PAL). A change in nail bed vascularity is thought to be responsible for PAL. The study was aimed at investigating the frequency of PAL in patients attending a liver disease clinic, the factors associated with its presence, its value for detecting cirrhosis, its prognostic value for mortality, and associated capillaroscopic findings.A total of 521 patients were included (age range, 18–94 years; 69% men). Systematic nail photographs were evaluated by 2 independent investigators. Disease-related data were obtained from the medical records. Mortality was evaluated after 7 years of follow-up. Nailfold capillaroscopy was performed on a subset of 80 patients.PAL was present in 228 patients (43.8%; Terry nails in 205, Lindsay nails in 20, and both in 3). The kappa-coefficient of interobserver agreement was 0.82. The presence of PAL was associated with cirrhosis and, accordingly, with portal hypertension and hepatocellular dysfunction. The positive likelihood ratio of PAL for the diagnosis of cirrhosis was 1.6 (95% CI 1.3–1.92). PAL was independently associated with chronic alcohol abuse and was not a significant predictor of mortality. Venous loop dilatation and prominence of the venous plexus were observed on capillaroscopy in patients with cirrhosis but were not significantly associated with PAL.In summary, PAL is a common finding in patients from a liver clinic; it is associated with liver cirrhosis and with alcohol abuse. PAL is not associated with specific capillaroscopic findings. We propose the generic term proximal apparent leukonychia instead of classic eponymous titles to avoid confusion in the literature. 相似文献
50.
Charlotte W Ockeloen Marjolein H Willemsen Sonja de Munnik Bregje WM van Bon Nicole de Leeuw Aad Verrips Sarina G Kant Elizabeth A Jones Han G Brunner Rosa LE van Loon Eric EJ Smeets Mieke M van Haelst Gijs van Haaften Ann Nordgren Helena Malmgren Giedre Grigelioniene Sascha Vermeer Pedro Louro Lina Ramos Thomas JJ Maal Celeste C van Heumen Helger G Yntema Carine EL Carels Tjitske Kleefstra 《European journal of human genetics : EJHG》2015,23(9):1270-1185
Loss-of-function variants in ANKRD11 were identified as the cause of KBG syndrome, an autosomal dominant syndrome with specific dental, neurobehavioural, craniofacial and skeletal anomalies. We present the largest cohort of KBG syndrome cases confirmed by ANKRD11 variants reported so far, consisting of 20 patients from 13 families. Sixteen patients were molecularly diagnosed by Sanger sequencing of ANKRD11, one familial case and three sporadic patients were diagnosed through whole-exome sequencing and one patient was identified through genomewide array analysis. All patients were evaluated by a clinical geneticist. Detailed orofacial phenotyping, including orthodontic evaluation, intra-oral photographs and orthopantomograms, was performed in 10 patients and revealed besides the hallmark feature of macrodontia of central upper incisors, several additional dental anomalies as oligodontia, talon cusps and macrodontia of other teeth. Three-dimensional (3D) stereophotogrammetry was performed in 14 patients and 3D analysis of patients compared with controls showed consistent facial dysmorphisms comprising a bulbous nasal tip, upturned nose with a broad base and a round or triangular face. Many patients exhibited neurobehavioural problems, such as autism spectrum disorder or hyperactivity. One-third of patients presented with (conductive) hearing loss. Congenital heart defects, velopharyngeal insufficiency and hip anomalies were less frequent. On the basis of our observations, we recommend cardiac assessment in children and regular hearing tests in all individuals with a molecular diagnosis of KBG syndrome. As ANKRD11 is a relatively common gene in which sequence variants have been identified in individuals with neurodevelopmental disorders, it seems an important contributor to the aetiology of both sporadic and familial cases. 相似文献