[On the anticoagulant effect of chlorazol fast pink; Antagonistic effect of polyvinyl pyrrolidone].
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Anticoagulants↗
Biomedical subjects
A Laurent
Publications and source records attributed to A Laurent.
In vitro transmission and antigenicity of a retrovirus isolated from a multiple sclerosis patient.
We have recently isolated an apparently novel retrovirus (LM7) from a patient with multiple sclerosis (MS). We present here results showing that (1) LM7 retrovirus can be transmitted in vitro to a normal human leptomeningeal cell culture and that (2) specific antibody against this retroviral strain can be detected in MS cases. Our results suggest that, if this virus is an endogenous retrovirus, it is different from human endogenous elements already described.
Antibodies, Viral↗
Leptomeningeal cell line from multiple sclerosis with reverse transcriptase activity and viral particles.
A leptomeningeal cell line (clonal but not immortal) was isolated from lumbar-punctured cerebrospinal fluid in a patient with definite multiple sclerosis (MS). This cell line, named LM7, was characterized by immunocytochemical and ultrastructural analyses and was found to produce specific viral reverse transcriptase activity, whereas electron microscopy revealed the presence of viral particles. This patient had no antibodies against human T-leukaemia virus type 1 (HTLV-I) or human immunodeficiency viruses types 1 and 2 (HIV-1, HIV-2). Moreover, monoclonal antibodies against HTLV-I and HIV-1 failed to recognize epitopes in induced LM7 cells. The possible relationship between MS and the virus present in LM7 cells is discussed.
Antibodies, Monoclonal↗
Tubal sterilization by means of selective catheterization: comparison of a hydrogel and a collagen glue.
PURPOSE: To test, in an animal model, two potentially suitable materials for nonsurgical selective tubal sterilization. MATERIALS AND METHODS: A hydrogel that forms an in situ plug by phase inversion of a polymer solution was placed in four rabbit fallopian tubes, and a proprietary collagen glue was placed into three rabbit fallopian tubes by means of transvaginal fluoroscopic fallopian tube catheterization. As controls, 11 tubes were catheterized without sterilization material injection. The rabbits were bred, and the presence of embryos was confirmed with palpation and at autopsy. Histologic analysis was performed. RESULTS: The short-term contraception rate was 100% in the hydrogel group, 33% in the collagen glue group, and 0% in the control group (P < .001 hydrogel group, P not significant in collagen group). Inflammation was minimal in the three groups (P not significant). CONCLUSION: The collagen glue had an insufficient contraceptive effect and should be abandoned. The hydrogel used proved effective and biocompatible, and long-term studies of this compound are warranted.
Acrylonitrile↗
Esterase-triggered fluorescence of fluorogenic oligonucleotides.
In the prooligonucleotide approach, a step of activation by cellular esterases is necessary for the removal of internucleoside phosphate masking groups and subsequent intracellular delivery of active antisense oligonucleotides. The efficacy of this approach implies that prooligonucleotides, once they are taken up by cells, are demasked by esterases during their course to their nucleic acid targets. In this regard, a method for labeling oligomers with esterase-activable fluorogenic tag was designed. The two phenolic functions of carboxyfluorescein were protected by pivaloyl groups, yielding a nonfluorescent lactone which was further activated as a N-hydroxysuccinimide ester. Two nuclease-resistant phosphorothioate 18-mer and methylphosphonate 19-mer oligodeoxynucleosides were attached to this biprotected fluorescein derivative via an amino linker at the 5'-end of the oligomers. The two conjugates were assayed for their carboxyesterase substrate ability in different biological media. In the presence of purified esterases or when incubated in serum or cell extracts, both oligonucleotide conjugates became fluorescent. In addition, the phosphorothioate oligoconjugate was microinjected into the cytoplasm of human fibroblasts, and a fast cytoplasmic release of fluorescence was observed with a rapid translocation of the fluorescent oligomer into the nucleus.
Ammonia↗
Melanine value in the stria vascularis of pigmented guinea-pigs treated by kanamycin.
In a previous report, kanamycin (400 mg/kg/d) seemed to increase the number of melanine granulations in intermediate cells of the stria vascularis, especially in the second and third turns. To precise these data, melanine was studied in those turns by ultrastructural morphometry in a control group with 12 animals. We observed a large intra-individual and inter-individual variation before intoxication. Thus, the meaning of melanine modifications by kanamycin must be carefully evaluated.
Animals↗
[Vulnerability to schizophrenia. III: Importance and limits of the Identical Pairs Continuous Performance Test].
Since several investigations have shown attentional deficits both in patients with schizophrenia and in subjects at high risk for schizophrenia, these deficits could be valuable vulnerability markers for schizophrenia. The aim of this study was to investigate wether non psychotic relatives of schizophrenic probands have deficits in sustained attention as measured by the Continuous Performance Test, Identical Pairs (CPT-IP) version. The study subjects were 25 schizophrenic probands, 50 of their first-degree relatives and 46 normal controls. For each subject, attention was assessed during 6 experimental conditions (2 standard, 2 slow, 2 easy conditions) of visual stimuli (digit-numbers and shapes). In each of the six conditions, the value of the sensitive index d' in the first-degree relative group was at an intermediate level between the patient and control groups. Moreover, in the standard shape condition, the d' value was significantly lower in the schizophrenic and in the relative groups than in the control group. This deficit was all the more interesting since it was not explained by a deficit in general intellectual abilities or by psychopathology such as anxiety or depression. Furthermore, the schizophrenic patients made more random errors in the standard and in the slow number conditions than both other groups. All groups improved their performance when the stimulus duration increased and when the processing load decreased. As a conclusion, this investigation seems: 1) to confirm the existence of an attentional deficit in the first-degree relatives of patients with schizophrenia; 2) to demonstrate the interest of the CPT-IP to detect this deficit. It must be emphasized that in order to detect the deficit, one only needs to explore the standard shape condition and that under such circumstances, the CPT-IP test has the advantage of being less time consuming than tests used in previous studies.
Adult↗
Organic solvents for pharmaceutical parenterals and embolic liquids: a review of toxicity data.
Non-aqueous solvents have long been used in subcutaneous or intramuscular pharmaceutical formulations to dissolve water-insoluble drugs. In recent years, the need for these vehicles was increased since the drug discovery process has yielded many poorly water-soluble drugs. Besides, preparations containing embolic materials dissolved in undiluted non-aqueous water-miscible solvents have been proposed for the intravascular treatment of aneurysms, arteriovenous malformations, or tumors. These organic solvents, regarded as chemically and biologically inert, may show pharmacological and toxicological effects. Therefore, knowledge of tolerance and activity of non-aqueous solvents is essential before they can be administered, especially when given undiluted. This paper focuses on thirteen organic solvents reported as possible vehicles for injectable products and details toxicological data when they have been administered intravascularly. These solvents can be subdivided into three groups according to their description in the literature either for intravenous pharmaceutical parenterals or for intravascular embolic liquids: well-documented organic solvents (propylene glycol, polyethylene glycols, ethanol), solvents described in specific applications (dimethyl sulfoxide, N-methyl-2-pyrrolidone, glycofurol, Solketal, glycerol formal, acetone), and solvents not reported in intravascular applications but potentially useful (tetrahydrofurfuryl alcohol, diglyme, dimethyl isosorbide, ethyl lactate). This review of the literature shows that toxicity data on intravascular organic solvents are insufficient because they concern solvents diluted with water and because of the lack of comparative evaluation using the same methodologies.
Animals↗
[Executive and amnestic functions of a group of first-degree relatives of schizophrenic patients].
Several lines of evidence seem to indicate that some neurocognitive measures could be phenotypic markers of predisposition to schizophrenia. The aim of this study was to investigate 21 patients with schizophrenia, 51 of their first-degree relatives and 46 nonpsychiatric controls, with a series of tests known to be sensitive to prefrontal cortical damage--the Trail Making Test, part B (TMT B), the Wisconsin Card Sorting Test (WCST) and a verbal fluency test (VFT)- and/or sensitive to temporo-hippocampic dysfunctions: verbal and visual memory and verbal learning tests from the Wechsler Memory Scale-Revised (Wechsler, 1987). Since parents and siblings share on average 50% of their genes with the schizophrenic proband, firstly we predicted that the first-degree relatives' performance would be at an intermediate level between patients and control subjects and secondly, we expected that a higher proportion of relatives than of control subjects would be impaired. The patients demonstrated deviant patterns of neuropsychological performance on the three tests sensitive to frontal dysfunctions and on most of the memory and learning tests. In the relative group, performance on the TMT B, VFT, immediate verbal recall and verbal learning was at an intermediate level between both other groups and significantly impaired compared to control subjects. However, the relative group did not differ from the control group on the WCST, immediate visual recall, and delayed verbal and visual recalls. Furthermore, compared to the control group, the percentages of patients and relatives who scored one standard deviation below the mean control group were significantly higher for the VFT and immediate verbal recall scores. Among all the tests studied, the verbal fluency and the immediate verbal recall appeared to be valuable phenotypic markers of schizophrenia since: (i) their mean scores were poorer in the patient and in the relative groups, (ii) the percentages of patients and relatives with poor performance were higher than the percentage of controls, (iii) these deficits were not due to poorer general intellectual abilities in the relative group, (iv) these deficits did not correlate with anxiety or depression scores.
Adult↗
[Vulnerability to schizophrenia: neuropsychological performance and schizotypal personality traits].
Although some neuropsychological deficits and a high rate of schizotypal personality disorders have been found in the first-degree relatives of patients with schizophrenia, few studies have looked for a link between those two types of potential marker of vulnerability to this disease. The aims of this study were: 1) to confirm some executive/attentional deficits in a group of first-degree relatives including not only siblings but also parents; 2) to evaluate the schizotypal traits using the French version of 4 self-reporting scales proposed by Chapman and his colleagues; 3) to look for a dependence or independence between the neuropsychological performance and the scores on the scales of schizotypy. Twenty four patients with schizophrenia, 48 of their first-degree relatives and 31 controls were included in the study. Both attentional tests (a Digit Symbol Substitution Test and a Degraded Stimulus-Continuous Performance Test) confirmed a worse performance in the patient and in the first-degree relative groups than in the control group. On the opposite side, the executive performance assessed by the Wisconsin Sorting Card Test, was poorer in the patient group only. Scores of the first-degree relative group on the social anhedonia, physical anhedonia and perceptual aberrations scales were at an intermediate level between those of the patient and control groups; moreover, only scores on the social anhedonia scale tended to be significantly higher in the first-degree relative group than in the control group. Among the first-degree relative group, the only significant correlation found was between the number of perseverative errors on the WCST and the scores on the physical anhedonia scale.
Adolescent↗
[Analysis of pharmaceutical products by low pressure chromatography on anion or cation exchangers].
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Anion Exchange Resins↗
[Study of P 300 in schizophrenia. Some reflexions on methodological difficulties].
We underscore the methodological difficulties in studying cognitive evoked potentials in schizophrenic patients. The main difficulties of such a study include the interruption of medication, the need of cooperation and immobility of subjects during the recordings, as well as of a correct patient-control matching for motivation, intellectual quotient, social and cultural levels. To establish correlations between clinical symptomatology and P 300 amplitude and latency we used both the DSM III-R and clinical rating scales. Clinical and electrophysiological testing must be performed the same day and have an excellent interrater agreement. Otherwise correlations are not reliable. Use of small patient samples is one major drawback which prevents to draw definitive conclusions. These difficulties usually unsaid are inherent to research in biological psychiatry and may partially explain the heterogeneity of results in the literature.
Electroencephalography↗
[Personality dimensions and neuropsychological performance in first-degree relatives of patients with schizophrenia and by affective psychosis].
Several studies have found a significant increase in the prevalence of some personality disorders in the first-degree relatives of patients with schizophrenia; other studies have found subtle neuropsychological deficits in these relatives. However, little is known about the specificity of the personality traits reported or about the relationship between these traits and the neuropsychological deficits. One hundred first-degree relatives of patients with schizophrenia (AS) and 88 first-degree relatives of affective psychotic (APA) patients completed the Eysenck Personality Questionnaire which measures extraversion, neuroticism, psychoticism. They were also administered the National Adult Reading Test (NART), the Trail Making Test (TMT) and a Verbal Fluency Test (VFT). In the AS group, the male relatives scored significantly higher on the psychoticism scale than the male relatives in the APA group. There were no significant differences in personality between female relatives of the 2 patients groups. In the AS group, the NART scores were superior when the psychoticism scores were lower and the TMT performance was better when the extraversion scores were higher. These results seem to indicate some specificity as well as sex differences of the psychoticism dimension. Moreover, the relationship between the personality dimensions and the neuropsychological performance could indicate that psychoticism increases vulnerability to schizophrenia whereas extraversion decreases it.
Adult↗
Biocompatibility of 1-French polyethylene catheters used in interventional neuroradiology procedures: a study with rats and dogs.
This study was designed to investigate the thrombogenicity, inflammatory response, and endothelial response to the presence of sterilized, 1-French polyethylene catheters implanted into the arterial system and subcutaneous tissues of 18 rats and two dogs. At time periods ranging from 1 week to 6 months, repeat angiography was done, the animals sacrificed, and the tissues containing the catheter removed for histologic study. In the subcutaneous tissues the catheter became encased in a very thin (less than 0.5 mm) coating of fibrous tissue with no evidence of inflammation. In large vessels, the catheter at all time periods appeared identical both angiographically and histologically to that at the time of implantation. In small to medium-sized vessels a slight increase in vessel size (25% increase in diameter of the rat iliac) was observed angiographically. On histologic evaluation, there was evidence of myointimal hypertrophy, which was asymmetrically placed, centered around the position of the catheter. There was no evidence of thrombi or of incorporation of the catheter itself into the hypertrophic tissue. In dogs and rats, an implanted 1-French polyethylene catheter is well tolerated: the animals showed no evidence of thrombotic, thromboembolic, or inflammatory complications. Myointimal hypertrophy was observed in small to medium-sized arteries, which is of unknown significance.
Animals↗
[Lupus erythematosus in a newborn. A case of placental transmission of the LE factor].
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Adult↗
[Prediction of hyaline membrane disease by studying pulmonary surfactant in amniotic fluid (author's transl)].
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Amniotic Fluid↗
[The P 300 potential in schizophrenia].
UNLABELLED: The P3 component of the event-related potential (E.R.P.) is an endogenous positive wave with a latency of approximately 300 msec, which is typically elicited by rare target stimuli in a detection task. The P3 has been applied to the study of cognitive impairments. One of the most consistently replicated biologic observation in schizophrenia is the P3 amplitude reduction. More recently, a prolonged P 3 latency has been observed by some authors. Nevertheless, when the heterogeneity of the schizophrenic syndrome is taken into consideration, results reported in the literature do not show much agreement. In the present study, we attempted to explore the P 3 component in a group of schizophrenic patients with a precisely defined clinical symptomatology. METHODS: Subjects. The study included 19 inpatients and 19 healthy control subjects age and sex-matched. Patients were medication-free for at least 15 days prior recording. According to the DSM III-R diagnosis criteria, 10 patients were classified as "paranoid subtype" and 9 as "disorganized subtype". Furthermore, on the day of the neurophysiological examination, the patients were interviewed using the Scale of the Assessment of Positive Symptoms (S.A. P.S.) and the Scale of the Assessment of Negative Symptoms (S.A.N.S.). The median age (SD) of the patients was 35.3 +/- 8 years, with a median duration of illness 12.5 +/- 7.2 years, a median duration of hospitalization 4.2 +/- 4.3 years and a median IQ 82.8 +/- 13.7. E.R.P. Recording. Subjects performed a two-tone auditory discrimination task: they were instructed to count silently infrequent high-pitched tones of 2000 Hz randomly presented within a serie of low-pitched tones of 1000 Hz. E.R.P. were recorded from 16 scalp electrodes (international 10-20 system) referred to nose. The P 3 was defined as the most positive wave between 250 and 500 msec after the stimulus onset. The amplitude was measured referred to the prestimulus baseline; the latency was measured at the point of maximum amplitude. Statistical analysis. The data were submited to a statistical analysis (ANOVA, Student's t-test, Fisher PLSD and Scheffe F-test, Spearman's correlation and linear regression analysis). RESULTS: 1) The schizophrenic group (N = 19) showed both a significantly prolonged latency and a reduced amplitude, compared to the control group (p < 0.01). 2) In the paranoid subgroup (N = 10), P 3 response was later and smaller than in the control group (p < 0.05). The P 3 latency and amplitude were not significantly different between the two groups of disorganized schizophrenics and controls. 3) A significant correlation between the global score of the S.A.P.S. and the P 3 amplitude was found (r = -0.67). There was no significant correlation between the P 3 parameters and a) the global score of the S.A.N.S. and b) the different items of each evaluation scale. 4) The P 3 amplitude showed a trend toward a negative correlation with the duration of hospitalization. 5) The duration of hospitalization was more important and the global score of the S.A.P.S. was higher in the paranoid than in the disorganized subgroup. There were no significant differences concerning the global score of the S.A. N.S., age, duration of illness, duration of hospitalization, IQ and performances in the detection task between the two subgroups of patients. DISCUSSION: We confirmed the P 3 parameters modifications in schizophrenic patients. The P 3 reduced amplitude and prolonged latency only in the paranoid subgroup, while the disorganized subgroup had both values comparable to those of the controls, is the main finding in our study. Kütcher or Louza studies tend to the same results. Furthermore, we showed that task performances or clinical measures such as age, duration of illness, duration of hospitalization or IQ did not account as biases of P 3 parameters. These results could be a further indication that different subtypes of schizophrenia may have different biological substrates.
Adult↗
Comparative viscosity and erythrocytes disaggregation shear stress of blood-radiographic contrast media mixtures in three mammalian species.
We compared blood viscosity and red blood cells (RBC) disaggregation shear stress in three mammalian species (humans, pigs and sheep) before and after adding water-soluble iodinated contrast media (CM): Ioxaglate (ionic CM) and Iopromide (non ionic CM). The two CMs had a diluting effect on the blood of the three species, which resulted in a viscosity decrease at all shear rates. However, viscosity rose slightly at low shear rates (in relation to increase of RBC aggregation) and low CM concentrations (10%), regardless of the ionic or non ionic nature of the CM. The two CMs had a similar proaggregant effect in human and pig's bloods. The proaggregant effect was slightly more pronounced with the ionic CM. We concluded that the pig is more suitable than the sheep for in vivo assessment of blood/CM mixture.
Animals↗