Mental symptoms in Parkinson''s disease during chronic treatment with levodopa

The influence of epidural block with bupivacaine (Marcaine-adrenalin) on fetal heart rate, uterine activity, and the frequency and intensity of contractions was studied in twenty-five nulliparae at term. Uterine activity was found to decrease during the first 30 minutes following epidural block. In the time interval 30 to 40 minutes after epidural block uterine activity increased again and attained the same level as during the last 10 minutes before analgesia. The frequency of uterine contractions did not decrease after the block. The lower levels of uterine contractility were due only to a lower amplitude of the contractions. The regularizing effect of epidural analgesia on incoordinate uterine action was noted. The recording of fetal heart rate in the time interval studied revealed no pathological findings. Mode of delivery, mean labour duration and Apgar scores after epidural block were comparable with earlier studies of a larger patient population. This study suggest that epidural analgesia does not induce any important changes in fetal heart rate but temporarily decreases uterine activity.     

Proliferation, differentiation, and long-term culture of primary hippocampal neurons

Primary embryonic hippocampal neurons can develop morphologically and functionally in culture but do not survive more than a few weeks. It has been reported that basic fibroblast growth factor (bFGF) promotes the survival of and neurite elongation from fetal hippocampal neurons. We report that bFGF, in a dose-dependent manner, can induce the survival (50 pg to 1 ng/ml) and proliferation (10-20 ng/ml) of embryonic hippocampal progenitor neurons in vitro. In serum-free medium containing high concentrations of bFGF, neurons not only proliferated (4-day doubling time) and differentiated morphologically but also could be passaged and grown as continuous cell lines. The neuronal nature of the proliferating cells was positively established by immunostaining with several different neuron-specific markers and by detailed ultrastructural analyses. The proliferative effect of bFGF was used to generate nearly pure neuronal cell cultures that can be passaged, frozen, thawed, and cultured again. Neurons have been maintained > 5 months in culture. The ability to establish long-term primary neuronal cultures offers the possibility that clonal lines of distinct neuronal cell types may be isolated from specific areas of the central nervous system. Such long-term neuronal cultures should prove valuable in studying neurons at the individual cell level and also in exploring interactions between neurons in vitro. The observed dose dependence raises the possibility that cell survival and proliferation in vivo may be influenced by different levels of bFGF.     

Fear of humans in Japanese quail selected for low or high adrenocortical response

Behavioral reactions to a nearby human were recorded in male Japanese quail of two lines selected for reduced (LS; low stress) or exaggerated (HS; high stress) plasma corticosterone (B) response to brief mechanical immobilization. Their adrenocortical responses to one of three treatments were then examined. These were: no human disturbance (undisturbed controls, CON), capture and return to the home cage before recapture and bleeding after 5 min (CR), or capture and manual restraint for 5 min before blood sampling (CREST). Quail of the HS line showed more fear-related behavior (crouching, escape) and avoidance of the experimenter than did their LS counterparts. Plasma B concentrations were markedly elevated following each capture treatment (CREST > CR) and the response appeared to be more pronounced in quail of the HS than the LS line. These findings indicate that HS quail perceived human contact to be more aversive than did those of the LS line. Avoidance scores and the adrenocortical responses to capture were positively correlated within individual birds. Therefore, simple behavioral tests of fear may have predictive value concerning physiological responsiveness to stressful stimulation.     

An evaluation of evolutionary constraints on microsatellite loci using null alleles

A test to evaluate constraints on the evolution of single microsatellite loci is described. The test assumes that microsatellite alleles that share the same flanking sequence constitute a series of alleles with a common descent that is distinct from alleles with a mutation in the flanking sequence. Thus two or more different series of alleles at a given locus represent the outcomes of different evolutionary processes. The higher rate of mutations within the repeat region (10(-3) or 10(-4)) compared with that of insertion/deletion or point mutations in adjacent flanking regions (10(-9)) or with that of recombination between the repeat and the point mutation (10(-6) for sequences 100 bp long) provides the rationale for this assumption. Using a two-phase, stepwise mutation model we simulated the evolution of a number of independent series of alleles and constructed the distributions of two similarity indices between pairs of these allele series. Applying this approach to empirical data from locus AG2H46 of Anopheles gambiae resulted in a significant excess of similarity between the main and the null series, indicating that constraints affect allele distribution in this locus. Practical considerations of the test are discussed.     

Clonal analysis of gliomas

In malignant gliomas, the characteristically heterogeneous features and frequent diffuse spread within the brain have raised the question of whether malignant gliomas arise monoclonally from a single precursor cell or polyclonally from multiple transformed cells forming confluent clones. Although monoclonality has been shown in surgically resected tissues, these may not include the full spectrum of patterns seen on autopsy material. Little is known about the clonality of low-grade gliomas from which malignant gliomas may sometimes arise. We sought to investigate the clonality of low-grade and malignant gliomas by using and comparing surgical and autopsy material with a Polymerase chain reaction (PCR)-based assay for nonrandom X chromosome inactivation. For that, purpose, archival surgical and autopsy material from 15 female patients (group A) (age 4 to 73 years; median, 45) with malignant gliomas (12 glioblastomas, one gliosarcoma, one anaplastic oligoastrocytoma, one gliomatosis cerebri), surgical material only from 21 female patients (group S) (age 6 to 78 years; median, 60) with low-grade and malignant gliomas (four low-grade astrocytomas, three oligoastrocytomas, two anaplastic astrocytomas, one gemistocytic astrocytoma, four oligodendrogliomas, seven glioblastomas) were analyzed. In group A, representative areas (mean = 5/patient; median = 7) were microdissected from tissue sections and assayed by PCR amplification of a highly polymorphic microsatellite marker locus of the human androgen receptor gene (HUMARA) in the presence of alpha32P with and without predigestion with a methylation-sensitive restriction enzyme (HhaI). Products were resolved by denaturing gel electrophoresis and autoradiographed. In group S, selected tumor areas were used for the assay. Each patient's normal brain tissue was used for control. The band intensity of alleles were measured by densitometric scanning. In group A, 13 of 15 cases were informative (heterozygous). The same pattern of nonrandom X chromosome inactivation was present in all areas of solid dense and moderate tumor infiltration in eight including all components of the gliosarcoma. Two of eight also showed focal loss of heterozygosity (LOH). One of 13 presented global LOH. Two of 13 showed microsatellite instability, one of which in a patient with Turcot syndrome, the other in gliomatosis cerebri. Opposite skewing patterns were seen in distant areas of gliomatosis cerebri consistent with oligoclonal derivation. Clonality remained indeterminate in one glioblastoma and in the anaplastic oligoastrocytoma because of skewed lyonization in the normal control. In group S, 19 of 21 cases were informative. Fifteen of 19 were monoclonal (four low-grade astrocytomas, one anaplastic astrocytoma, one gemistocytic astrocytoma, two oligodendrogliomas, one oligoastrocytoma, six glioblastomas). Four of 19 were indeterminate. We conclude that (1) Low-grade and malignant gliomas are usually monoclonal tumors, and extensively infiltrating tumors must result from migration of tumor cells (2) Gliomatosis cerebri may initiate as an oligoclonal process or result from collision gliomas (3) Biphasic gliomas likely arise from a single precursor cell. (4) LOH at the HUMARA locus is probably related to partial or complete deletion of an X-chromosome, which occurs in malignant gliomas during clonal evolution.     

Acute myocardial infarction: prognosis after recovery

A prognostic index for 2-year survival after recovery from acute myocardial infarction was constructed from variables obtained during its course. One hundred ten of 143 patients survived 2 years, and 27 of 33 patients died of cardiac-related causes. Univariate analysis showed that 12 variables were significantly different between the surviving and nonsurviving groups. Discriminant analysis indicated five variables with meaningful predictive value to be included in a prognostic index: admission systolic blood pressure; highest blood urea nitrogen level in the cardiac care unit: atrial arrhythmias in the cardiac care unit; angina pectoris for more than 3 months or a previous myocardial infarction; and more than one ventricular ectopic beat per hour recorded on a dynamic electrocardiogram during the 17th to 24th hospital day. The prognostic index emphasizes the importance of extensive myocardial impairment and provides a means for identifying patients at risk of early mortality.     

Technique of handling neonatal blood samples for zinc analysis

Short segments of Chemfluor flexible Teflon tubing (2.38 mm ID) previously coated with sodium heparin (1,000 units/ml) serve as ideal containers in which blood from neonates can be collected for zinc analysis. The ends of the tube are plugged with Teflon TFE round beading so that the sample comes in contact only with Teflon and the risk of contamination is minimized. The heparin coating facilitates easy collection of the sample and separation of plasma by centrifugation. It does not contribute zinc to the specimen.