A Study of Early Pregnancy Factor Activity in Preimplantation

PROBLEM and METHOD: Early pregnancy factor (EPF), an Immunosuppressive substance, which appears in pregnant women's sera 48 h after fertilization, is a kind of pregnancy-specific protein. To determine whether the EPF activity could be a super early indicator of pregnancy, we used rosette inhibition assay to detect EPF activity in the sera, collected from 70 women 2–7 days after ovulation intending to conceive monitored by ultrasonography. Simultaneously we selected 40 non-pregnant sera and 12 early-pregnant sera as negative control and positive control, respectively. RESULTS: The results of this study demonstrated that EPF activity is detected in 35 women's sera out of 70 women within 2–7 days after ovulation, and 28 women out of the 35 were pregnant, which was known by follow-up, and 7 were not pregnant, possibly due to either false positive results or embryo loss because of preimplantation failure, thus causing no pregnancy. The other 35 out of 70 had no EPF activity and 34 of them were not pregnant, which was known by follow-up, but one case became pregnant, which was false negative result. Our study showed that diagnosis of the super early pregnancy could be made by detecting EPF activity in maternal serum within the time of preimplantation. The accuracy of pregnancy diagnosis by this method is 88.6%, with a false negative rate of 3.4% and a false positive rate of 17.1%. The β-HCG level was measured from the above 70 women's sera in order to contrast EPF activity. All of the sera collected 2–6 days following ovulation indicated that there were lower β-HCG values in very early pregnancy (≥a5 mIU/ml). On the seventh day after ovulation, EPF activity was detected in 11 out of 15 sera with only 2 of them with a b-HCG level that reached or slightly surpassed that of the early pregnancy diagnosis (5 mIU/ml and 5.4 mIU/ml, respectively). This demonstrated that β-HCG is not the earliest signal of pregnancy; otherwise the EPF activity is one that appears 2–6 days earlier than β-HCG appears. We measured the progesterone level of the 48 sera from the 70 collected above within 2–7 days postovulation and found most of them reached the level of progesterone in the luteal phase (7.5–98.3 nmol/L). This indicated that ovulation had taken place in these women, which was in accordance with observations by ultrasonography. CONCLUSIONS: Our study showed that diagnosis (of 88.6%) of super early pregnancy could be made with an accuracy of 88.6% by detecting EPF activity in maternal serum within 2-days after ovulation. This offers a basis for pregnancy diagnosis for the women who attempt to terminate their pregnancy safely or who conceive unexpectedly, and it contributes to family-planning.     

Evaluation of endothelial cell migration with a novel in vitro assay system

In this study we introduce a novel in vitro 'oil-drop' assay system for the measurement of endothelial cell (EC) migration, based on the original concept of the Teflon fence assay (Pratt et al., 1984; Am. J. Pathol. 117: 349–354). An aliquot of 15–20,000 human umbilical vein EC (HUVEC) is pipetted through a layer of mineral oil. The cells readily attach, spread and migrate on the surface of a matrix-coated tissue culture dish as a confluent circular monolayer. Migration is measured as the net increase in the total area covered at 24 hours. We have used this system to quantify EC migration on matrices composed of a mixture of type I collagen and either von Willebrand factor (vWF) or fibronectin (FN) in the presence or absence of tumor necrosis factor (TNF). Plating efficiency on both vWF/collagen and FN/collagen, measured by counting cells after attachment and spreading, is about 80%. With this method, migration on vWF/collagen was about 6.4 mm² and 5.3 mm² for TNF-treated and untreated HUVEC, respectively. HUVEC migration on FN/collagen was slightly greater – 6.4 mm² and 6.5 mm² with and without TNF treatment, respectively. During the 24 hour time period, HUVEC numbers increased 30–40% on vWF/collagen, and 60–80% on FN/collagen, with increased proliferation observed with TNF- treatment. EC proliferation could be completely inhibited by 2 mM hydroxyurea. This assay system has proven useful in our studies to quantify cell migration and proliferation.     

树突状细胞在胆囊癌组织内浸润的研究

目的通过对胆囊癌组织中树突状细胞浸润情况的研究,阐述树突状细胞与肿瘤免疫之间的关系。方法采用免疫组化SP法。结果树突状细胞在胆囊癌组织的浸润程度与年龄、性别和病理组织学类型无关,与病理分化程度呈负相关关系(P<005)。结论树突状细胞在胆囊癌组织的浸润程度与病理分化程度、Nevin分期、肝浸润及淋巴结转移存在密切的关系。树突状细胞的定量检测可作为估计胆囊癌预后的标志。     

2450MHz介质复介电常数的测量

目的测量2450MHz频率下蒸馏水和不同浓度NaCl溶液的复介电常数,用以判定系统的可靠性和稳定性.方法根据微扰法得到复介电常数的测量公式,然后通过实验对已知参数的蒸馏水和NaCl溶液进行测量,并计算其复介电常数和电导率,验证计算结果的可靠性和稳定性.结果对计算结果进行统计分析和误差分析,其均值、标准差和变异系数表明,最终结果可与M.I.T标准较好地吻合.结论这种系统可较好地测量2450MHz频率下高损耗介质的复介电常数,测量系统的主要误差是由介质体积的误差引起的,因此精确测量介质体积是测量生物组织等高损耗介质复介电常数的关键.     

人类白细胞抗原-G突变体cDNA克隆及在K562细胞上的表达

目的：克隆人类白细胞抗原-G(Human leukocyte antligen-G，HLA-G)突变体cDNA，并使其在HLA-I类阴性的K562细胞上获得稳定表达，为研究配-受体之间的识别机制奠定基础。方法：用RT-PCR方法从人子宫蜕膜组织扩增出HLA-GcDNA，得到全长HLA-GPCR产物后，用桥式PCR方法进行定点点突变，将突变的目的基因亚克隆于逆转录，将突变的目的基因亚克隆于逆转录mG-pLNCX表达载体，采用感染的方法将重组质粒转入K562细胞，最后经G418筛选及有限稀释，利用单克隆抗体W6/32进行FACS及mRNA检测，观察HLA-G突变体在靶细胞表面的表达。结果：HLA-G突变体分子在经mG-pLNCX转染的靶细胞表面获得稳定高表达。结论：成功构建了mG-pLNCX表达载体，并使HLA-G突变体分子在HLA-I类阴性的靶细胞K562细胞上获得稳定表达。     

Significant HLA-A02 allelic variation revealed in chinese and caucasian populations

HLA-A2 subtypes (A^*0201 - ^*0212) were determined by oligotyping in HLA-A2 positive samples from four populations (Han Chinese, Dai Chinese, Caucasoids from Germany and Turkish individuals from Kayseri)(see table).

Two different findings can be concluded from this study: 1) Significant HLA-A^*02 allelic variations found in four populations. A^*0207 is the predominant A^*02 allele in the Dai population and absent in the German Caucasian and the Turkish population. In contrast, A^*0201 is the most prevalent allele in the Caucasian, Turkish and Han Chinese group. We also found a high proportion of A^*0206 and A^*0207 in Han Chinese. 2) A strong association has been found between A^*0207 and HLA-B46 and DR9 in the Dai minority population. This haplotype is also found in Han Chinese. Three DNA samples from Turkish and one from the Dai population are presently being sequenced because the reaction pattern was out of the expected (Supported by SFB 217)     

Influx of leukocytes and platelets in an evolving brain infarct (Wistar rat).

The results of several experimental studies of focal ischemia and anecdotal observations suggest that leukocytes may contribute to the injury initiated by an arterial occlusion. The timing and the nature of leukocyte responses in evolving brain infarcts (either human or experimental) are incompletely characterized. This is a study of experimental brain lesions in 96 Wistar rats that underwent occlusion of a large intracranial artery for variable intervals ranging between 30 minutes and 7 days. The experimental model, based on the occlusion of a middle cerebral artery ostium via the insertion of a nylon monofilament through the external carotid artery, does not require opening the skull; therefore, the inflammatory response is not influenced by the effects of craniotomy and changes in intracranial pressure are only those induced by the ischemic lesion. All 96 animals having the same type of arterial occlusion developed an ischemic brain lesion (limited to the territory of the corresponding artery) that evolved into an area of extensive neuronal necrosis over a period of 6 to 12 hours followed by pan-necrosis (infarct) approximately 60 hours later. In this study, leukocytes (in particular polymorphonuclear cells) were detected in the microvessels (capillaries and venules) of the ischemic hemisphere as early as 30 minutes after the arterial occlusion. Numbers of intravascular neutrophils peaked at 12 hours, whereas intraparenchymal granulocytes were most numerous at 24 hours; a few granulocytes were visible in the brain infarct as late as day 7. Circulating monocytes were first detected within the capillaries/venules of the ischemic area after 4 to 6 hours. Platelet aggregates were more abundant in the arterial than the venous side of the circulation, and luminal obstruction of arteries by platelet aggregates became noticeable only 48 hours after the arterial occlusion. Fibrin thrombi were conspicuous for their absence. These observations provide the background for studies that will attempt to unravel the relationship between the biological responses of leukocytes and neuronal necrosis secondary to focal ischemia.     

新生儿缺氧、缺血性脑病血中6-keto-PGF1α,NSE水平变化的临床研究

目的:探讨HIE患者血中6-keto-PGF1α、NSE水平变化及临床意义.方法:用RIA检测89例HIE患者和32例正常新生儿血中6-keto-PGF1α、NSE水平变化.结果:HIE轻、中、重度组6-keto-PGF1α水平与正常对照组比较,均存在显著性差异(p＜0.01),HIE患者轻度组NSE水平与对照组比较无显著性差异(p＞0.05),中、重度组NSE水平与对照组比较存在显著性差异(p＜0.01),6-keto-PGF1α、NSE二组血中浓度上升与HIE程度呈正相关.结论:HIE患者中6-keto-PGF1α、NSE水平检测,对判断HIE的脑损伤程度、治疗、预后观察,具有重要临床意义和应用价值.     

早期食管癌的病理形态观察及组织发生学探讨

目的探讨早期食管癌的组织发生学.方法对109例早期食管癌及癌周病变进行病理观察.结果其中20例的一点癌(黄豆大小),3例双原发癌,1例小细胞癌.癌周伴有不同程度的鳞状上皮异形增生和不典型增生.结论早期食管具有多样性生长的特点.提示临床医生在胃镜检查应注意多点取材,以防漏诊;以及正确确定手术范围,防止手术残留.     

真空紫外辐照对加成型硅橡胶光学性能的影响

考察了加成型硅橡胶在真空环境中经1000ESH紫外辐照后的性能变化。结果表明,辐照后材料均出现发黄的现象,光学透过率大幅度 下降,同时加入硅酸钾包覆后制备的热控涂层反射率下降。经原位测试与离位测试,发现加成型硅橡胶在两种不同条件下测得的结果差异较小,而在有机硅橡胶中加入ZnO后原位与离位测试结果则差异明显,表现出明显的漂白作用。