Heterosynaptic postactivation potentiation in hippocampal CA 3 neurons: Long-term changes of the postsynaptic potentials

Summary CA 3 neurons were excited synaptically by stimulation in the dentate hilus and the stratum radiatum of CA 1 in guinea pig hippocampal slices. Following repetitive stimulation (10–20 c/s, 10 s) of either stimulation site, the amplitudes of orthodromic population spikes or the probability of unitary discharges increased. Changes of the intracellularly recorded potentials were either (a) increased EPSP amplitudes associated with decreased IPSP amplitudes, or (b) increased IPSP amplitudes. A cell showing enhanced IPSPs after repetitive activation could respond with increased EPSP amplitudes and decreased IPSP amplitudes upon further repetitive activation. The potentiation, which was always preceded by a 5–10 min depression, lasted up to 3 h. This potentiation was heterosynaptic, since the responses to the non-stimulated input also changed and since the inputs were found to excite the pyramidal cells through separate synapses in double shock experiments. The heterosynaptic mode of the potentiation as well as the changes of the IPSPs indicate that not only the excitatory pathway but also the inhibitory pathway must be considered in explaining postactivation potentiation in this hippocampal field.     

Isolation and mapping of a polymorphic CA repeat sequence at the human VRK1 locus

VRK1 is a novel human putative serine/threonine kinase, and is located on chromosome 14 at band q32 where an autosomal recessive congenital microphthalmia (CMIC) is mapped. We isolated a polymorphic dinucleotide CA repeat marker from a genomic clone containing the human VRK1 gene. This polymorphism will be useful in genetic studies of disorders localized at the 14q32 region, such as CMIC. Received: October 8, 1998 / Accepted: October 16, 1998     

Integrins and adhesion molecules: Reliability and accuracy of polymerase chain reaction amplification of two unique target sequences from biopsies of cleavage-stage and blastocyst-stage human embryos

Human embryos have been biopsied at either the cleavage or theblastocyst stage of development. One to two blastomeres wereremoved from cleavage-stage embryos and 2–6 cells fromblastocysts. The biopsy specimens were subjected to gene amplificationby the polymerase chain reaction (PCR) and a comparison madeof amplification efficiencies of two unique target sequences,one located within the -globin gene and containing the sickle-celllocus and the other a polymorphic dinucleotide repeat. Whenthe cleavage-stage biopsy sample consisted of an intact blastomerewith a clearly discernible nucleus, an amplification efficiencyof 89% was achieved for each target locus. This was similarto that achieved with cleavage-stage biopsy samples consistingof two blastomeres or with blastocyst biopsy samples consistingof 2–3 trophectoderm cells. When biopsy samples consistedof four or more trophectoderm cells, both target loci were amplifiedin all samples tested. When the biopsy sample was heterozygousat the dinucleotide repeat locus and the biopsy consisted ofone or more intact cells with a clearly discernible nucleus,both alleles were amplified in >80% of biopsy samples. Whenfour or more trophectoderm cells were used for the PCR, bothalleles were amplified in all heterozygous samples. Target sequenceswere never amplified from biopsy samples which lysed prior totransfer into the reaction tube. Analysis of DNA fragments amplifiedfrom the dinucleotide repeat locus indicated that in most casesfaithful amplification of biopsy DNA template had taken place.However, in one case, fragments were identified which couldnot have resulted from the amplification of embryonic sequencesalone, indicating that contamination with extraneous DNA mayhave taken place. The significance of this finding for therapeuticpreimplantation genetic diagnosis is discussed.     

The measurement of CA 125 and placental protein 14 in uterine flushings in women with recurrent miscarriage; relation to endometrial morphology

The concentrations of CA 125 and placental protein 14 (PP14)were measured in uterine flushings obtained throughout the lutealphase of the cycle from eight normal fertile women. The concentrationsof both proteins increased in a similar pattern throughout theluteal phase of the cycle, with the most dramatic increase occurring6 days after their luteinizing hormone surge (day LH +6). However,a greater variation in CA 125 concentrations was seen comparedto that seen for PP14. The concentrations were compared to thoseobtained on day LH + 7 of the cycle from a group (n equals;35) of women with recurrent miscarriage. The ranges in concentrationof PP14 and CA 125 in the flushings of fertile and recurrentmiscarriage patients were very similar. However, a greater proportionof women with recurrent miscarriage (55%) had low concentrations(<5 ng/ml) of PP14 than in the control group (12.5%) andthe concentrations of PP14 in the uterine flushings were significantlyless (P < 0.05) in women with recurrent miscarriage comparedto the normal fertile group. There was no significant differencein the concentrationof CA 125 in the uterine flushings betweenthe two groups. Histological observation of the endometrialbiopsy samples from recurrent miscarriage patients gave menstrualcycle datings that ranged from day LH +2.5 to LH +6.5 with retardedendometrium (;day LH +5) in 12 of 35 (34%) patients. Of these12 patients, 10 (83%) had low PP14 concentrations and six (50%)had low CA 125 concentrations in their uterine flushings. Inthe recurrent miscarriage patients with histologically normal(sequals; day LH +5) endometrial development, 10 out of 23 (43%)also had low PP14 concentrations and 8 out of 23 (35%) had lowCA 125 in their uterine flushings. The results suggest thatPP14 is better than CA 125 as a marker for endometrial functionin this group of women. In some cases (52%) the low concentrationsof PP14 in the uterine flushings couldbe explained by retardedendometrial development but for the others the reduction inPP14 concentration in the uterine flushing was not associatedwith retardation of endometrial development.     

Mediated smoking cessation programs in the Stanford five-city project

Two mediated smoking cessation programs were subjected to a field evaluation. The Quit Kit is a printed self-help package, and "Calling It Quits" consists of five segments which were aired on the local television news. A sample of 239 persons requested the Quit Kit and were followed. At the 2-month and 12-month follow-ups, respectively, 13.6% and 17.9% of those surveyed reported abstinence. Results indicate the potential of mediated interventions.     

子宫内膜异位症并不孕患者腹腔镜电灼术治疗前后外周血EmAb及CA125值的差异与分析

目的：考察腹腔镜电灼术治疗子宫内膜异位症的疗效以及子宫内胰异位症与 ＥｍＡｂ和 ＣＡ１２５的关系。方法：应用腹腔镜诊断、电灼治疗子宫内膜异位症患者８０例,测定手术前后患者外周血ＥｍＡｂ和ＣＡ１２５,考察术后复孕率,并与非ＥＭＴ组６０例及Ｄａｎａｚｏｌ治疗组１５０例进行比较。结果：①随着患者ＥＭＴ分期的升级,ＥｍＡｂ值也呈上升的趋势,两者间存在良好的线性相关关系（ｒ２＝０．８８６,Ｐ＜０．０１）．同样的趋势也出现在ＣＡ１２５中。②各期ＥＭＴ患者的术前 ＥｍＡｂ和 ＣＡ１２５ 值均较非 ＥＭＴ组高（Ｐ＜０．０１）。③在 Ｉ～Ⅲ期间,术后 ＥｍＡｂ与 ＣＡ１２５ 值均较术前有显著性下降（其中Ⅰ、Ⅲ期组Ｐ＜０．０１;Ⅲ期组Ｐ＜０．０５）。④就总体而言,Ⅰ～Ⅳ期ＥＭＴ患者之间外周血的 ＥｍＡｂ没有显著性差异（Ｐ＞０．０５）,相反,各组间的 ＣＡ１２５则存在非常显著性差异（Ｐ＜０．０１）。⑤各期患者的术前、后的ＥｍＡｂ与ＣＡ１２５值之间呈现出显著正相关关系（Ｐ＜０．０１）。⑥腹腔镜组患者复孕率为５１．２５％（４１／８０）,Ｄａｎａｚｏｌ组复孕率为５７．３３％（８６／１５０）,两组间无差异显著性（Ｐ＞０．０５）。结论：腹腔镜诊断和治     

肺癌诊断中CYFRA_(21-1)、CA_(50)、CEA联检的临床意义

目的 :探讨血清CYFRA2 1- 1、CA50 、CEA变化对诊断肺癌的临床价值。方法 :应用放射免疫法对 186例肺癌患者进行血清CYFRA2 1- 1、CA50 、CEA联合检测。结果 :肺癌组患者血清CYFRA2 1- 1、CA50 、CEA检测水平明显高于正常对照组 (P <0 .0 1)、三项联合 (CYFRA2 1- 1+CA50 +CEA)检测的敏感性和准确性最高 ,分别为 :91.4 %、86.2 % ,优于二项和单项检测。结论 :三项肿瘤标志联合检测可提高肺癌的早期诊断率 ,在病情检测方面可为临床提供有价值的资料。     

PIK3CA突变在人类癌症发生中的作用

大量的研究证实多种人类实体肿瘤中存在着PIK3CA突变.PIK3CA是一种致癌基因,在肿瘤细胞中,其激酶活性增强,能持续刺激下游AKT,增加细胞侵袭和转移能力,因此在肿瘤的发生发展中起着至关重要的作用,同时对于临床诊断、治疗及预后有着重要意义.抑制PIK3CA突变将是一种新兴的分子靶向肿瘤治疗手段.