人源抗Trop-2 Fab对宫颈癌细胞生物学特性的影响

目的 :观察人源抗Trop-2 Fab对宫颈癌细胞生物学特性的影响。方法 :流式细胞术和免疫荧光检测宫颈癌Hela细胞表面Trop-2蛋白的表达;划痕实验和Transwell检测人源抗Trop-2 Fab对宫颈癌细胞迁移能力的影响;流式细胞术检测人源抗Trop-2 Fab对宫颈癌细胞凋亡的诱导作用;CCK-8(cell counting kit-8)检测人源抗Trop-2 Fab对宫颈癌细胞增殖的影响。结果:Hela细胞表面有Trop-2蛋白表达,人源抗Trop-2 Fab能够抑制Hela细胞的增殖,有效降低Hela细胞的迁移和侵袭能力,同时能够诱导Hela细胞凋亡。结论:人源抗Trop-2 Fab能明显降低宫颈癌细胞的恶性生物学行为,Trop-2可作为宫颈癌治疗的潜在靶点。     

人源抗TLR4抗体IgG的制备及其中和特性分析

目的:构建全人源抗人Toll样受体4(Toll-like receptor 4,TLR4)抗体轻?重链表达载体,在293Free style 细胞中表达并纯化,分析该重组全分子抗体的生物学活性?方法:设计引物扩增全人源抗人TLR4抗体可变区编码序列,将其分别克隆到真核表达载体pFUSE-CHIg-hG1和pFUSE-CLIg-hl中,共转染至293Free style 细胞,表达产物用protein A亲和层析柱纯化?应用酶联免疫吸附测定法(enzyme-linked immunosorbent assay,ELISA)?Western blot?免疫共沉淀?质谱分析及蛋白芯片检测抗体的免疫学特性,并检测该抗体对人单核细胞淋巴瘤THP1细胞肿瘤坏死因子(tumor necrosis factor,TNF)-α表达的影响?结果:成功构建全人源抗人TLR4抗体真核表达载体,获得的全分子抗TLR4抗体保持了与抗原的结合活性,对THP-1细胞TNF-α表达的抑制率可达85.7%?结论:重组全人源抗TLR4 IgG保持了与TLR4的结合特异性,并具有明显的中和作用,对炎症治疗具有潜在的应用价值?     

靶向Trop-2 CAR-T细胞的制备及其体外对卵巢癌细胞杀伤作用的研究

目的：制备靶向人滋养层细胞表面抗原2（human trophoblast cell surface antigen 2 , Trop-2)的嵌合抗原受体T细胞(chimeric antigen receptor T cell , CAR-T）,观察Trop-2 CAR-T细胞在体外对卵巢癌细胞增殖的影响。方法：运用分子克隆及基因重组技术构建Trop-2 CAR;采用Western blot检测Trop-2 CAR在293T细胞中的表达;CCK-8法检测Trop-2 CAR-T细胞对卵巢癌细胞增殖的影响;ELISA检测细胞因子分泌的变化。结果：酶切鉴定及测序分析结果表明,Trop-2 CAR各基因片段连接正确;Western blot检测结果显示,该质粒能够在293T细胞中有效表达;CCK-8结果显示,制备的Trop-2 CAR-T细胞在体外能明显抑制表达Trop-2的卵巢癌细胞的增殖（P＜0.05）;ELISA检测结果表明Trop-2 CAR-T细胞与表达Trop-2的卵巢癌细胞共培养后,干扰素（interferon-γ,IFN-γ)、白介素（interleukin-2,IL-2)细胞因子分泌增加（P＜0.01）。结论：该研究成功制备了Trop-2 CAR-T细胞,可有效抑制Trop-2表达阳性的卵巢癌细胞的增殖。     

人源抗H7N9血凝素中和抗体IgG的制备及鉴定

目的:将从全人源Fab噬菌体抗体库筛选获得的抗H7N9血凝素Fab抗体基因进行基因工程改造,以表达全分子抗H7N9血凝素中和抗体IgG,并验证其对H7N9型禽流感病毒的中和活性?方法:用H7N9型禽流感病毒血凝素筛选全人源Fab噬菌体抗体库,构建全分子IgG抗体重?轻链表达载体,共转染293 FreeStyle(293F)细胞,表达并纯化IgG抗体?应用ELISA及Western blot实验检测抗体免疫学活性,微量中和实验及鸡胚预防保护实验检测其中和活性,血凝抑制试验判断其结合血凝素亚基?结果:成功筛选出1株全人源抗H7N9血凝素Fab抗体基因并构建IgG真核表达载体?获得的全分子IgG抗体重?轻链序列正确,并可特异性结合H7N9血凝素?微量中和实验证明其对H7N9型禽流感病毒有良好中和活性,中和滴度为15.6 μg/mL?鸡胚预防保护实验显示抗体用量为200 μg时可达100%保护率?血凝抑制试验表明其结合血凝素HA2亚基?结论:制备的重组全人源全分子抗H7N9血凝素IgG抗体可特异性识别H7N9型禽流感病毒血凝素,对H7N9型禽流病毒有显著的中和作用,为进一步研发用于禽流感防治的抗体药物奠定基础?     

人源抗c⁃Met抗体与rAGAP偶联物对卵巢癌细胞生物学特性的影响

目的：制备人源抗c?Met的全分子抗体（c?Met?IgG1）及其与重组东亚钳蝎镇痛抗肿瘤多肽（recombinant analgesic?antitumor peptide,rAGAP）偶联的新型抗体（c?Met?IgG1?rAGAP）,分析它们的生物学特性,检测其对卵巢癌细胞生物学行为的影响。方法：以本实验室保存的人源抗c?Met抗体基因为模板,构建c?Met?IgG1?rAGAP真核表达载体并转染真核细胞,表达并纯化抗体偶联物。通过亲和力检测、免疫荧光、流式细胞术等方法,评估c?Met? IgG1和c?Met?IgG1?rAGAP的生物学特性。通过CCK?8、划痕实验、Transwell侵袭实验检测抗体对卵巢癌细胞增殖、迁移和侵袭的影响。结果：成功制备出能够与c?Met蛋白特异性结合的c?Met?IgG1和c?Met?IgG1?rAGAP两种抗体;一系列实验证明了c?Met?IgG1和c?Met?IgG1?rAGAP均可抑制c?Met阳性的卵巢癌细胞HO8910的增殖、迁移、侵袭,且c?Met?IgG1?rAGAP对卵巢癌细胞的抑制作用要强于c?Met?IgG1,而在c?Met阴性的IOSE386细胞中并未观察到这些作用。结论：研究结果表明c?Met?IgG1?rAGAP可靶向作用于c?Met阳性的卵巢癌细胞并具有抗肿瘤活性,可为探索卵巢癌的分子靶向治疗奠定研究基础。     

人源抗Trop-2抗体Fab的制备及条件优化

目的:探讨人源抗Trop-2抗体片段Fab在大肠杆菌中的诱导表达,优化蛋白表达及纯化的条件?方法:将含有抗Trop-2 Fab 抗体基因的质粒转化宿主菌E.coli TOP10F ′大肠杆菌,比较诱导前培养液更换对抗Trop-2 Fab片段表达量的影响;比较不同诱导温度?诱导时间及诱导前加入葡萄糖对蛋白表达的影响;大量表达的抗Trop-2 Fab经亲和层析纯化后,用免疫荧光和流式细胞术检测其免疫学特性?结果:在培养液中加入5 g/L的葡萄糖,人源抗Trop-2抗体Fab片段的表达产量明显增加;16℃的诱导温度比其它温度能表达更多的Fab分子;加诱导剂12 h,目的蛋白的表达量至峰值?结论:本实验结果为在原核系统中大量制备抗Trop-2抗体片段及后续的肿瘤靶向治疗提供了基础?     

人源抗TLR4抗体IgG2对对乙酰氨基酚诱导小鼠急性肝损伤的保护作用

目的：研究人源抗TLR4 抗体IgG2（human?TLR4 IgG2,hTLR4 IgG2）对对乙酰氨基酚（acetaminophen,APAP）诱导肝损伤的保护效应,探讨其在药物性肝损伤中的保护作用。方法：以人源抗TLR4 抗体Fab基因为模板,扩增其可变区基因,构建人源抗TLR4抗体IgG2真核表达载体,转染CHO?S细胞,筛选稳定表达细胞株,收集细胞上清,Protein G柱纯化抗TLR4抗体IgG2。将18只C57BL/6J 小鼠随机分成3组：生理盐水组、APAP（600 mg/kg）组和APAP +hTLR4 IgG2（5 mg/kg）组,统计小鼠腹腔注射APAP后 24 h的存活率;重复上述实验分组,检测小鼠腹腔注射APAP 8 h后,血清中丙氨酸氨基转移酶（alanine aminotransferase,ALT）、天门冬氨酸氨基转移酶（aspartate transaminase,AST）、白细胞介素?1（interleukin?1,IL?1）、白细胞介素?6（interleukin?6,IL?6）和肿瘤坏死因子?α（tumor necrosis factor?α,TNF?α）的表达水平,取肝脏做病理分析并使用Western blot检测凋亡蛋白的表达。结果：成功构建并表达纯化人源抗TLR4抗体IgG2;ELISA结果显示,抗体效价为1∶204 800。与APAP组相比,APAP+hTLR4 IgG2组小鼠的24 h存活率显著增加（P < 0.05）;血清AST、ALT以及炎性细胞因子的表达水平显著降低,具有统计学意义（P < 0.05）;病理分析结果显示,与模型组相比,人源抗TLR4抗体IgG2治疗组的小鼠肝组织炎性细胞浸润、充血和坏死等症状明显改善;Western blot结果显示凋亡相关蛋白的表达减少。结论：人源抗TLR4抗体IgG2能够抑制炎症因子的表达及细胞凋亡,对APAP诱导的小鼠肝损伤有显著的保护作用。     

人源全分子抗c-Met 抗体的制备及对鼻咽癌细胞生物学特性的影响

目的:利用基因工程技术制备全分子人源抗 c-Met抗体,分析该抗体免疫学特性,并观察该全分子抗体对鼻咽癌细胞增殖?迁移和侵袭的影响?方法:设计引物扩增抗c-Met Fab抗体的重轻链可变区序列,将其分别克隆到真核表达载体pFUSE-CHIg-hG1 和 pFUSE-CLIg-hκ 中?转染真核细胞,表达产物用Protein A柱纯化?通过ELISA?Western blot和免疫荧光等方法鉴定该抗体的免疫学特性?CCK-8检测抗体对人鼻咽癌细胞增殖的抑制作用,划痕实验?Transwell侵袭实验分析抗体对人鼻咽癌细胞迁移和侵袭的影响?结果:成功重组全分子人源抗c-Met 抗体的表达载体,获得的全分子抗体保留了与抗原的特异性结合活性?CCK-8实验中结果显示全分子抗体能抑制c-Met阳性鼻咽癌细胞CNE2和HONE1的增殖?细胞划痕和Transwell侵袭实验结果显示全分子抗体能抑制c-Met阳性细胞CNE2和HONE1的迁移和侵袭能力?结论:本研究成功制备人源全分子抗c-Met抗体,该抗体有明显的中和活性,为探索鼻咽癌分子靶向治疗奠定了基础?     

人源抗TROP2全分子抗体IgG的真核表达及对胰腺癌细胞增殖的抑制作用

目的:以人源抗TROP2抗体Fab基因为模板,构建人源抗TROP2全分子抗体IgG真核表达系统,观察人源抗TROP2全分子抗体IgG对胰腺癌细胞增殖的抑制作用?方法:分别扩增抗TROP2抗体的重链和轻链基因,构建人源抗TROP2全分子抗体IgG的重组表达载体pWS-anti-TROP2,转染CHO dhfr-细胞,加MTX筛选抗体表达量高的单克隆株,Protein G 亲和柱纯化,获得人源抗TROP2全分子抗体IgG?SDS-PAGE?Western blot?ELISA?免疫荧光和流式细胞术等方法鉴定人源抗TROP2全分子抗体IgG并分析其免疫学活性?MTT法分析人源抗TROP2全分子抗体IgG对胰腺癌细胞BxPC-3的增殖抑制作用?结果:成功构建了人源抗TROP2全分子抗体IgG的真核表达系统,表达并纯化人源抗TROP2全分子抗体IgG?经鉴定,抗体的轻链与重链大小与预期一致,可与TROP2蛋白特异性结合,效价可达1∶6 400?MTT检测结果表明,人源抗TROP2全分子抗体IgG对胰腺癌BxPC3细胞的增殖有明显的抑制作用,且呈时效?量效依赖关系?结论:本研究成功构建了人源抗TROP2全分子抗体IgG的真核表达系统,并证明此抗体可特异性识别胰腺癌细胞表面的TROP2蛋白,且对胰腺癌细胞的增殖有明显的抑制作用?     

全人源抗狂犬病病毒scFv-Fc融合抗体的制备及活性分析

目的:制备全人源抗狂犬病病毒scFv-Fc融合抗体,并分析其结合活性?方法:构建全人源抗狂犬病病毒scFv-Fc融合抗体原核表达载体,优化表达并纯化全人源抗狂犬病病毒scFv-Fc融合抗体?以纯化的灭活狂犬病病毒包板,对纯化的抗体进行结合活性分析?结果:构建全人源抗狂犬病病毒scFv-Fc-pColdⅡ原核表达载体,经测序分析正确后,转入大肠杆菌BL21(DE3)进行表达,在加入浓度为0.5 mmol/L IPTG时,scFv-Fc融合抗体的表达较高,其分子量大小为57 000?纯化后的scFv-Fc融合抗体在1∶512的条件下仍可以较好地结合狂犬病病毒?结论:构建全人源抗狂犬病病毒scFv-Fc-pColdⅡ原核表达载体,表达并纯化了scFv-Fc融合抗体,为研发狂犬病暴露后预防治疗性抗体药物奠定了基础?     

Value of D-Dimers in patients with acute aortic dissection

Objective: To evaluatel the value of D-dimers in patients with acute aortic dissection (AAD). Methods: This study consisted of 16 patients with AAD and 27 non-AAD patients. Serum D-dimets were measured by Sta-Liatest D-DI immunoturbidimetric assay. Results: D-dimer level was higher (P ＜ 0.001) in patients with AAD(7.91 ± 5.52 μg/ml) than that in non- AAD group(1.57±1.24 μg/ml). D-dimer was positive (＞0.4 μg/ml) in all patients with AAD and in 10 control group patients (37%). Among patients with acute AAD, D-dimers tended to be higher in Stanford A than in Stanford B (8.67 ± 4.31 μg/ml vs. 3.24±1.27 μg/ml, P ＜0.01). D-dimer values tended to be higher in more extended disease(3.84 ± 1.65 μg/ml, 8.57 ± 3.58 μg/ml and 11.87 ± 5.69 μg/ml in thoracic aorta, thoracic and abdominal aorta, thoracic and abdominal aorta and iliacal arteries, respectively, P ＜ 0.05 for both 8.57 ± 3.58 and 11.87 ± 5.69 vs. 3.84 ± 1.65 ). Including the control group into the analysis, we found a sensitivity of 100%, a negative predictive value of 100%, and a specificity of 66% and a positive predictive value of 64% for D-dimer in diagnosis of AAD in our patients with suspected AAD. Conclusion: D-dimer was elevated in patients with AAD. A negative D-dimer test result could be useful in excluding AAD.     

Research of combined liver-kidney transplantation model in rats

Objective： To set up a simple and reliable rat model of combined liver-kidney transplantation. Methods： SD rats served as both donors and recipients. 4℃ sodium lactate Ringer＇s was infused from portal veins to donated livers,and from abdominal aorta to donated kidneys, respectively. Anastomosis of the portal vein and the inferior vena cava （IVC） inferior to the right kidney between the graft and the recipient was performed by a double cuff method, then the superior hepatic vena cava with suture. A patch of donated renal artery was anastomosed to the recipient abdominal aorta. The urethra and bile duct were reconstructed with a simple inside bracket. Results： Among 65 cases of combined liver-kidney transplantation, the success rate in the late 40 cases was 77.5%. The function of the grafted liver and kidney remained normal. Conclusion： This rat model of combined liver-kidney transplantation can be established in common laboratory conditions with high success rate and meet the needs of renal transplantation experiment.     

BLOOD PRESSURE CHANGE WITH AGE IN SALT-SENSITIVE TEENAGERS

Objective To observe blood pressure change with age in salt-sensitive teenagers whose salt sensitivity were determined by repeated testing.Methods Salt sensitivity was determined through intravenous infusion of normal saline combined with volume-depletion by oral diuretic furosemide in 55 teenagers. After five years, salt sensitivity was re-examined and subject blood pressure was followed up. Blood pressure changes in salt-sensitive teenagers were compared to that of non-salt sensitive teenagers over five years.Results After 5 years, the repetition rate of salt sensitivity determined by intravenous saline loading is 92.7%. In teenagers with salt sensitivity on the baseline, both the systolic blood pressure increments and increment rates were much higher than non-salt sensitive teenagers (12.7±12.1 mmHg vs. 2.8±5.2 mmHg, P＜ 0.01; 12.2%± 12.0% vs. 2.5% ±4.4%, P＜ 0.001,respectively). There was a similar trend for diastolic blood pressure (8.4 ± 6.4 mmHg vs. 3.7 ± 6.4 mmHg, P = 0.052; 13.2% ±10.6 % vs. 6.8%± 10.1%, P = 0.053, respectively).Conclusions Salt sensitivity determined by intravenous saline loading showed good reproducibility. Blood pressure increments with age were much higher in salt-sensitive teenagers than non-salt sensitive teenagers, especially in terms of systolic blood pressure.     

安心颗粒对急诊经皮冠状动脉介入术后生活质量影响的研究

目的：评价使用安心颗粒对急诊经皮冠状动脉介入术（PPCI）术后生活质量的影响.方法：将160例接受PPCI的急性ST段抬高型心肌梗死患者随机分为安心颗粒组（术前顿服安心颗粒8.8g,术后安心颗粒4.4 g/次,每日2次）和对照组（仅接受基础药物治疗）.所有患者均服用阿司匹林、氯吡格雷和阿托伐他汀.分别在入院时、出院前1d、出院后180 d时,应用心肌梗死多维度量表（MIDAS）、中文版SF-36评价量表对患者生活质量评分.并观察术后30 d以内的出血并发症、血小板减少症发生情况.结果：入院时和出院前1d,两组患者的心肌梗死MIDAS、SF-36量表评分比较无差异（P＞0.05）;出院后180 d时,与对照组比较,安心颗粒组MIDAS、SF-36评分明显减低（P＜0.05）;组内与入院时比较,两组出院前1d、出院后180 d时,MIDAS、SF-36评分均降低（P＜0.05）.两组患者在随访期间均无大量出血、少量出血、重度和极重度血小板减少症发生,安心颗粒组有4例、对照组有7例发生不明显出血（P＞0.05）.两组发生轻度血小板减少症的患者数比较无差异（P＞0.05）.结论：PPCI使用安心颗粒,能改善急性ST段抬高型心肌梗死患者的生活质量,且不增加出血风险.     

The comparative studies of the influences of Urapidil and Nicardipine on sino-atrial node function, atrio-ventricular node function and hemodynamics

Objective:To investigate the influences of urapidil and nicardipine on rabbit sinus function,atrio-ventricular node function and hemodynamics.Methods:Thirty-two Angora's rabbits were selected and randomly divided into four groups.U1 group:urapidil 0.25 mg/kg;U2 group:urapidil 0.5 mg/kg;N1 group:nicardipine 10 μg/kg;N2 group:nicardipine 20 μg/kg.All these medicine were administrated within 30 seconds.Measurements were taken before and after the administration of urapidil or nicardipine for the following data:mean blood pressure(MAP),heart rate(HR),sino-atrial conduction time(SACT),maximal sinoatrial recovery time(SNRTmax)corrected sinus node recovery time(CSNRT),index of sinus node recovery time(SNRTI),Wenckebach A-V conduction frequency (WB),and P-R interval.Results:Significant MAP and HR changes were identified in all of the four groups before and after administration of both urapidil and nicardipine.No significant changes could be found in the rest of the parameters.Intergroup analysis showed that SACT and CSNRT of N1 and N2 groups were shorter than those of the U2 group(P＜0.01);the MAP decreased(P＜0.01)and the HR increased drastically(P＜0.01).Conclusions:Neither urapidil(0.25 mg/kg,0.5 mg/kg)nor nicardipine(10μg/kg,20μg/kg)has any significant influence on rabbit sinus function or rabbit atrio-ventricular node function.Nicardipine could be a better choice than urapidil for parafunctional sinus node patients.     

Expression of OPGmRNA and ODFmRNA in the patients of hip fracture due to osteoporosis

Objective：To investigate the gene expression of osteoprotegerin（OPG） and osteoclast differentiation factor（ODF） in the bone tissue of patients with hip fracture due to osteoporosis. Methods：OPGmRNA and ODFmRNA in the bone tissue in 50 cases of osteoporosis sufferers（over 50 years old） with hip fracture（Observer Group） and 30 cases of hip facture sufferers with no osteoporosis（Control group） were analyzed with the Semi-Quantitative RT-PCR method. Results：The mRNA expressed of ODF, OPG were both high in the patients with hip fracture. In the control group, the expression of OPG mRNA was observed, while the expression of ODF mRNA was very slight. Conclusion：Aged patients contained all signals including OPG, ODF that are essential for inducing osteoclastogenesis and promoting bone resorption.     

The clinicopathological and immuohistochemical analysis of solid-pseudopapillary tumor of the pancreas： report of 9 cases

Objective：To investigate the clinical features, pathological characteristics and immunophenotype of solid-pseudopapillary tumor of the pancreas（SPTP）. Methods：Nine surgically treated cases of SPTP were retrospectively reviewed. Hematoxylin and Eosin（HE） staining and immunohistochemical staining were used to analyze all cases, and the general clinical data was collected. Results：Six patients were asymptomatic except for a palpable mass. Two patients complained of vague-epigastric pain. One patient appeared jaundice. The tumor was encapsulated and solid tissues alternately with cystic tissues. Histologically, the histological structure of solid portion was pseudopapillary with a fibrovascular core. Tumor cells were uniform and medium-sized which were arranged in sheets ets or nests or pseudopapillary patterns. Immunohistochemical studies demonstrated that SPTP proved positive in vimentin（9/9 cases）, AAT（9/9 cases）, NSE（9/9 cases）, ACT（7/9 cases）, CK20（2/9 cases）, CgA（1/9 cases）, S-100（3/gcases）, PR（4/gcases）, Syn（3/9 cases） and CD56（5/9cases）, negative in CEA and ER. Conclusion：SPTP is a tumor predominantly occurring in young women frequently without special symptoms. This tumor has various characteristical histological patterns with different immunophenotype.     

Dynamic Changes in Serum Estradiol and Progesterone levels in Patients of Premenstrual Syndrome with Adverse Flow of Liver-qi

Objective:To probe into the influence of changes of ovarian hormones on the pathogenesis of the specific sub-type premenstrual syndrome(PMS)and reveal partial microcosmic mechanisms of adverse flow of liver-qi.Methods:Estradiol(E2)and progesterone(P)levels in serum were determined at different phases of menstrual cycle by radioimmunoassay.Results:In the group of PMS with adverse flow of liver-qi.the secretive peak value Of E2 and P at the follicular phase significantly decreased,and the secretive peak value at the luteal phase did not come into being.Conclusions:Low E2 and P secretive peak at the follicular phase and absence of secretive peak at the luteal phase is one of the microcosmic mechanisms of PMS with adverse flow of liver-qi.One of the pathophysiologic mechanisms of specific sub-type PMS is probably the continuous low level of E2and P.     

Real-time Three-dimensional Echocardiography in Assessment of Left Ventricular and Right Ventricular Volumes

Real-time three-dimensional echocardiography (RT3DE)is a new ultrasound technique that enables dynamic threedimensional visualization and quantification of the heart in real time. Investigation of feasibility and methodology of RT3DE in determining left ventricular (LV) and right ventricular (RV) volumes, RT3DE was performed in 35 normal adults using Philips SONOS 7500 system with a 2-4 MHz matrix array transducer. The 60°×60° "pyramid" volume database was obtained and analyzed on a TomTec echo workstation. Both LV and RV volumes were calculated with four 3DE methods (i.e. apical 2, 4, 8, and 16-plane) through manually tracing ventricular endocardial borders in end diastole and end systole. Stroke volumes were then calculated. LV volume was also measured by 2DE Simpson's rule using GE VIVID 7 ultrasound machine.     

SCREENING FOR A 21-CHROMOSOME ABNORMALITY IN PREIMPLANTED EMBRYOS OF ELDERLY WOMEN

Increasing maternal age is the only etiological factor unequivocally linked to Down's syndrome in humans. The occurrence rate of newborns with Down's syndrome is about 1/220 in women over 35 years old. However, the occurrence rate in embryos fertilized in vitro, of the elder woman is unclear. Using FISH we screened the number of chromosome 21 in preimplanted embryos of 5 elderly women (average age, 38.4 years) to study the feasibility and necessity of screening trisomy 21 in embryos in patients over 35 years old at the in vitro fertilization (IVF) center.