Electroencephalographic changes in experimental autoimmune myasthenia gravis

A procedure for the determination of activity and linkage specificity of sialidases is described. The sialoglycoprotein fetuin is coated onto a microtiter plate and incubated with sialidases from different sources. Enzymatic activities and linkage specificities are then determined by a sandwich method which measured the binding of different lectins to fetuin. The lectins used were peanut agglutinin (PNA) from Arachis hypogaea, which binds specifically the galactose beta-1-3-N-acetylgalactosamine structures that are unmasked following sialidase treatment of fetuin, the lectins from Sambucus nigra (SNA) and Maackia amurensis (MAA) that are specific for alpha-2-6 and alpha-2-3 bound sialic acids, respectively, and the slug agglutinin from Limax flavus (LFA) that is specific for N-acetyl and N-glycolyl neuraminic acids. Increased PNA and decreased LFA, SNA, and MAA lectin binding correlated with sialidase-induced desialylation of the substrate. In this report, the assay was used to determine the activities and specificities of influenza, Vibrio cholerae, and Arthrobacter ureafaciens sialidases.     

Electroencephalographic laterality changes during human sexual orgasm

Left and right parietal EEGs were recorded while seven subjects experienced sexual climax through self-stimulation. EEG data were quantified by continuous cumulated measurements of the integrated areas of EEG recording during successive 1-sec epochs. In eight out of 12 experiments, this measure revealed a statistically significant change in laterality. Controlled replications with two of the original subjects obviated the possibility that two potential sources of artifact (hand used for masturbation and gross body movements) accounted for the changes. While previous research has focused on vasomotor and myotonic indices of sexual response, this study demonstrates the significance of brain phenomena in sexual orgasm.     

Developmentally regulated changes in the cell surface architecture of Leishmania parasites

The cell surface of Leishmania parasites is coated by a highly unusual glycocalyx which varies markedly during the parasite life cycle. The predominant molecule on the extracellular promastigote (sandfly) stage is a complex lipophosphoglycan (LPG), which together with a number of GPI-anchored proteins and a family of low molecular weight glycoinositolphospholipids (GIPLs), forms a morphologically distinct protective coat over the plasma membrane. The structure of the LPG has been shown to vary in different species and during promastigote development in the sandfly. This polymorphism is thought to be important in allowing Leishmania parasites to colonize a range of insect hosts, and in facilitating the regulated migration of promastigotes along the sandfly alimentary canal. Stage-specific changes in LPG are also involved in preadapting promastigotes to life in the mammalian host. This complex glycocalyx coat is absent from the amastigote stage that proliferates in the phagolysosomes of mammalian macrophages, as the expression of both the LPG and GPI-anchored proteins is massively down-regulated. Instead, the plasma membrane of amastigotes is coated by a densely packed layer of parasite-derived GIPLs and host-derived glycosphingolipids. We propose that the down-regulation of the promastigote macromolecules and the acquisition of host glycolipids by amastigotes represents an important strategy to avoid detection by specific and non-specific components of the immune system.     

Tissue antigens in the saliva of rats. Demonstration of salivary gland specific and nonspecific antigens

Antisera were raised in rabbits against the half-saturated ammonium sulfate soluble fraction of rat saliva. With these antisera, at least four antigens were demonstrated by immunodiffusion in the saliva and in a saline extract of the parotid gland; three of these antigens were also found in a saline extract of the submaxillary gland. Two of the four antigens were salivary gland specific, the other two being shared by the liver,pancreas and testis. The immunofluorescent pattern indicates that these antigens originate from the acinar epithelium of the salivary glands and probably constitute products of secretion and/or cellular turnover.     

Electroencephalographic evaluation in Sturge-Weber syndrome

The most consistent electroencephalographic finding in 16 cases of Sturge-Weber syndrome was a unilateral reduction of background amplitude in the waking record. Comparable asymmetries were noted in those patients in whom sleep recording also was done. Physiologic responses (to hyperventilation and photic driving) usually were decreased on the involved side. These hemispheric electroencephalographic abnormalities are detectable in infancy even before the characteristic intracranial calification develops. Epileptiform activity, when focal, was limited to the involved hemisphere.     

Absorbance changes of carotenoids in different solvents

Carotenoids are typically measured in tissues with the high performance liquid chromatography (HPLC) and quantitation is usually done by calibrating with stock solutions in solvents. Four carotenoids including lutein, zeaxanthin, lycopene and beta-carotene were dissolved in hexane and methanol respectively, and their absorbance characteristics were compared. Lutein shows absorbance spectra that are almost independent of solvents at various concentrations. Spectra of zeaxanthin, lycopene and beta-carotene were found to be more solvent-dependent. The absorbance of zeaxanthin at lambda max is about approximately 2 times larger in methanol than in hexane at the higher concentrations, and increased non-linearly with increasing concentration in hexane. The absorbance of lycopene at lambda max in hexane is approximately 4 fold larger than in methanol, but the absorbance of the methanol sample can be recovered by re-extracting this sample in hexane. The absorbance of beta-carotene in hexane is larger than in methanol, and increased linearly with increasing concentration. But beta-carotene showed a non-linear concentration effect in methanol. There are very small variations in lambda max for all four carotenoids between hexane and methanol, due to differences in molar extinction coefficients. The non-linear concentration effects for these carotenoids are probably due to differences in solubility leading to the formation of microcrystals. Thus, care should be taken with quantitation of tissue carotenoid values, when they depend on measurement of concentrations in stock solutions.     

Electroencephalographic findings in Tanzanian epileptic patients

Electroencephalogram (EEG) of 524 Tanzanian epileptic patients seen between 1985 and 1987 were reviewed. Over two thirds were young patients between the ages of five and thirty. Four hundred and fifty (86%) had abnormal records. Eighty nine per cent of abnormal records had focal abnormality and 11% had centrencephalic abnormality. Grand mal seizures did not imply centrencephalic abnormality, only 13% had such abnormality. Petit mal seizures are rare, over one third of these had temporal focal abnormality. Partial seizures were associated highly with focal abnormality. However, complex partial seizures did not imply temporal focal abnormality. Implications of EEG findings to correlation with epileptic seizures is discussed.     

Electroencephalographic findings in liver function disorders

Abnormal rhythmisations in the EEG are described in hepatoportal encephalopathy as an expression of a disturbance of more profound cerebral structures. The EEG gives an actual information about the state of the cerebral functions of all stages of a hepato-cerebral decompensation and allows a reliable prognostic estimation during the observation of the course. Practically significant are also bioelectric findings of a disturbance of the cerebral function with clinically symptom-poor course in compensated liver cirrhosis or obstructive icterus.     

Zinc counteracts experimentally-induced cirrhotic changes in rats

In the present study, cirrhosis was induced in rats by administration of carbon tetra chloride for 8 weeks. In these animals ZnSo4 (equivalent to 100 and 200 micrograms of zinc) was administered orally and liver function tests and plasma zinc (Zn) estimations were carried out after 2 and 4 week intervals. The results revealed that Zn supplement counteracts cirrhotic changes in liver.     

Genistein-induced changes in lipid metabolism of ovariectomized rats

The effect of the isoflavone, genistein, on the lipid metabolism of ovariectomized rats was studied. Three types of experiments were performed. In the first one, the rats were fed diets supplemented with 0.01 or 0.1% of genistein for 14 days. In the second and third experiments, the direct effect of genistein on the liver and fat tissue were measured respectively by means of liver perfusion or incubation of isolated adipocytes with the isoflavone. Genistein in food significantly decreased blood serum and muscle triglyceride concentrations and increased the level of free fatty acids in serum. Serum free cholesterol was diminished and liver cholesterol was enhanced after genistein ingestion. When genistein acted directly on the liver during perfusion, a smaller incorporation of 14C-glucose into lipids was observed, and in parallel a greater output of free fatty acids into the medium was noticed. These changes were accompanied by diminution of the liver triglyceride contents. Genistein, acting on the adipocytes strongly depressed both basal and insulin-induced lipid synthesis, when glucose was used as a substrate. The effect of the isoflavone alone on the lipolysis in the adipocytes was negligible. However, it intensified lipolysis induced by epinephrine. The results obtained let us conclude that genistein in food can reduce the fattening processes in ovariectomized rats. This effect of genistein may be attributed, at least in part, to its direct influence on lipid metabolism in the liver and adipose tissue.     

Developmental changes in intestinal globule leukocytes of normal rats

The relationship between sex hormone concentrations and female genital swelling during the menstrual cycle in the monogamous gibbon was comparable with that of polygamous female primates, such as the chimpanzee, which live in multimale groups and have larger swellings. The data, therefore, support the hypothesis proposed by C. R. Carpenter more than 50 years ago, that the gibbon's genital swelling, like that of other female primates, reflects basic physiological processes associated with progress of the menstrual cycle. Genital swelling increased during the follicular phase with increasing concentrations of oestradiol and oestrone glucuronide, reached maximal swelling in association with the mid-cycle peaks in the oestrogens and LH and began detumescence with the initial increases in progesterone during the luteal phase. The data also suggest that the menstrual cycle of the gibbon is shorter than previously reported, since cycles of 19-22 days exhibited hormone patterns that are consistent with ovulation. The genital swelling of the female gibbon is a useful marker for monitoring progress of the menstrual cycle and the presumptive time of ovulation.     

Peripheral nerve vascular changes in spontaneously hypertensive rats

Circulation to the brain is affected by hypertension. Hypertension-dependent cerebrovascular changes were documented primarily in brain pial arteries, whereas no information is so far available concerning changes of peripheral nerve vascularization in hypertension. This study was designed to assess the occurrence of structural changes of interfascicular and intrafascicular arteries supplying peripheral nerves (the so called vasa nervorum) in spontaneously hypertensive rats (SHR). The investigation was performed in 8-month-old SHR, by using standard microanatomical techniques associated with quantitative image analysis. In SHR a significant increase of systolic pressure values accompanied by thickening of the arterial wall, narrowing of the lumen and increase of the wall-to-lumen ratio were observed in comparison with age-matched normotensive Wistar-Kyoto rats. Hypertension-related structural changes involved primarily interfascicular arteries and to a lesser extent intrafascicular arteries. These findings indicate that similarly as documented for cerebral arteries, the vascular supply to peripheral nerves is impaired in hypertension. Structural changes of interfascicular and intrafascicular arteries of SHR could lead to ischemia of peripheral nerves. Further work is in progress to evaluate the functional relevance of hypertensive changes to peripheral nerve vasculature.     

Similarity and co-expression of tumour-associated antigens recognised by different monoclonal antibodies

The concentration of carcinoembryonic antigen (CEA), CA130, CA125, SLX, CA19-9, SPan1, and tumour-associated glycoprotein 72 (TAG-72) in the culture supernatant of 15 cancer cell lines and in the sera of 58 cancer patients was measured, and the co-expression of these antigens was examined by double determinant immunoradiometric assays. The high correlation coefficient of the concentrations and significant binding in the double determinant assays indicated a close relationship between CA125 and CA130 and between CA19-9 and SPan1. There was variable binding of the 125I-labelled anti-SLX, anti-CA19-9, and anti-SPan1 antibodies to anti-CA130 beads that had been pre-incubated with the culture supernatants, suggesting the presence of the epitopes of SLX, CA19-9, and SPan1 on the molecule expressing CA130. Similarly, the epitopes of SLX, CA19-9, and SPan1 could be present on the molecule expressing CEA. 125I-labelled anti-CA19-9, anti-SLX, and anti-TAG-72 antibodies were bound in variable proportions to anti-CA130 beads or to anti-CEA beads that had been pre-incubated with patients' sera. However, CEA and CA130 were not expressed on the same molecule, either in the culture supernatant, or in patients' sera. In conclusion, the carbohydrate epitopes of CA19-9, SPan1, SLX, and TAG-72 could be present on the molecule recognised by the anti-CA130 or anti-CEA antibody; however, the epitopes of CA130 and CEA did not co-exist on the same molecule.     

Electroencephalographic changes in patients with cardiopathies, subsequently operated under extracorporeal circulation. Significance and outcome. Evaluation of 679 cases

This study analysed the pre-operative electroencephalographic recordings of 679 patients with heart disease, later undergoing surgery under extra-corporeal circulation. The type and the severity of the abnormalities are listed for each heart disease. These results are compared to those already published in the literature on this subject and are discussed in terms of a number of possible aetiological factors: the age of the patients, data provided by the pre-operative cardio-pulmonary assessment. This analysis does not enable us to demonstrate, with any statistical significance, the aetiological factor(s) of these electroencephalographic alterations. Finally, comparison of the pre-, intra- and postoperative EEG in the same patients enables us to evaluate the prognostic value of these electrical abnormalities.     

Electroencephalographic correlates of prism adaptation in mentally retarded individuals

Sensorimotor adaptation was studied in 23 institutionalized, mentally retarded individuals. This was achieved by recording the pattern of off-target pointing errors resulting from viewing through a 20-diopter prism. The results showed a wide range of individual differences in prism adaptation. The electroencephalogram (EEG) was also recorded from four scalp locations and analyzed by computer to determine EEG intensity, coherence, and phase angle. Correlations between EEG and behavioral scores of prism adaptation revealed a number of significant relationships, especially negative correlations between alpha intensity and prismatic adaptation. These results indicate that patterns of central nervous system activity are meaningful related to sensorimotor capabilities in retarded individuals.     

Electroencephalographic findings in patients with mucolipidosis type IV

To evaluate their prognostic value, the expressions of CD44v and sialyl LeX (SLX) in colorectal cancers were studied immunohistochemically. Tissue specimens were reacted with monoclonal antibodies (mAb) CD44-1V and CSLEX-1. Of the 145 colorectal cancer patients undergoing curative resection, 59 (40.7%) were positive for mAb CD44-1V, and 40 (27.6%) were positive for mAb CSLEX-1. There was a significant correlation between the combined expression of SLX and CD44v8-10 and lymph node metastasis. The patients with tumors negative for CD44v8-10 and SLX had the most favorable prognoses. Conversely, the patients with tumors positive for both CD44v8-10 and SLX had a high recurrence rate and the poorest prognoses. In a multivariate analysis using the Cox regression model, the combined expression of SLX and CD44v8-10 emerged as an independent prognostic indicator. These results suggested that the combined expression of CD44v8-10 and SLX may be a biologic marker of prognostic significance.     

Electroencephalographic concomitants of a caffeine-induced panic reaction

This paper addresses two new challenges to the rehabilitation team. The first is to continue to provide high quality services in an era when government and other regulations place constraints on what the rehabilitation team can offer. The second challenge is to honor the ideal of patient empowerment in this era of policy constraint. Ethical issues involved in responding constructively to these challenges are discussed and practical suggestions offered.