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P Baruch

Publications and source records attributed to P Baruch.

At least 19 recordsLinked to original sources
PubMed1999

Crystallization and preliminary diffraction studies of two quinoprotein alcohol dehydrogenases (ADHs): a soluble monomeric ADH from Pseudomonas putida HK5 (ADH-IIB) and a heterotrimeric membrane-bound ADH from Gluconobacter suboxydans (ADH-GS).

Crystals of a soluble monomeric quinocytochrome alcohol dehydrogenase (ADH-IIB) and of a trimeric membrane-associated quinocytochrome alcohol dehydrogenase (ADH-GS) have been obtained. The ADH-IIB crystals are triclinic, with one monomer in the unit cell, and were obtained in the presence of PEG 8000, sodium citrate, HEPES buffer and 2-propanol. X-ray data were collected at 110 K to 1. 9 A resolution (R(merge) = 6.4%) and the orientation of a methanol dehydrogenase search molecule (from Methylophilus methylotrophus W3A1) was obtained by molecular replacement. Preliminary refinement of this model (10.0-3.0 A resolution, R = 0.37, R(free) = 0.40) led to tentative identification of the two highest peaks in a native anomalous difference Fourier map as the Fe atom of the heme and a calcium ion interacting with the PQQ prosthetic group. The ADH-GS crystals are tetragonal, displaying six similar lattices, both primitive and centered, and were grown by the sitting-drop method after replacement of Triton X-100 by dodecylmaltoside or octaethylene glycol monododecyl ether in the presence of ammonium sulfate and sodium acetate buffer, with and without PEG 3500 and calcium ion. The best diffraction is obtained at 110 K where the resolution extends to about 4 A in the a and b directions and about 3 A in the c direction.

Alcohol Oxidoreductases↗
PubMed1997

Distractibility and processing resource deficit in major depression. Evidence for two deficient attentional processing models.

Performance on the Stroop Color-Word Test is impaired in depression, but it is not clear whether this impairment reflects a distractor inhibition disturbance or a reduction of processing resources. In this study, untreated major depressives were evaluated using a modified computerized Stroop Test composed of three tasks: to name the color of XXXXXs, of nonconflicting words, and of conflicting color words. It was hypothesized that, unlike color words, nonconflicting word distractors would disturb the color naming task only in the presence of a primary distractor inhibition disturbance. The slow reaction time (RT) depressives and normal RT depressives, according to their color naming speed without distractors, were contrasted to distinguish depressives with and without clear signs of resource deficit. It was found that interference produced by nonconflicting words was greater in normal RT depressives than in either slow RT depressives or control subjects, while interference caused by color words was dramatically stronger in slow RT depressives than in other groups. Results suggest the existence of two different attentional deficit patterns in clinical depression: some depressives have a distractor inhibition disturbance while others are deficient in processing resources.

Adolescent↗
PubMed1996

Attention disturbance in clinical depression. Deficient distractor inhibition or processing resource deficit?

Cognitive impairments in depression have recently been proposed as secondary to more basic attentional disturbances. Studies have shown that performance on the Stroop Color-Word Test is impaired in depressives, but it is not clear whether this impairment reflects a primary distractor inhibition disturbance or a more global cognitive dysfunction, such as a reduction of processing resources. In the present study, unmedicated clinical depressives were evaluated using a computerized Stroop Color-Word Test and the Visuo-Spatial Interference Test, a selective attention task that makes fewer demands on resources. Compared with normal subjects, depressives presented increased choice reaction times (CRT) and interference in both tests. Correlations were found between CRT and interferences only in depressives, favoring the processing resource hypothesis. Further exploratory analysis comparing the more rapid depressives and the slower normal subjects on CRT revealed that although these subgroups had comparable CRT, rapid depressives still exhibited increased interference on the Visuo-Spatial Interference Test. Thus, in non- or mildly retarded patients, a specific distractor inhibition deficit was observed in absence of resource deficit.

Adult↗
PubMed1995

SSRIs in anxious-agitated depression: a post-hoc analysis of 279 patients.

A post-hoc analysis of nine controlled antidepressant trials examined the intensity of the initial anxiety and agitation of depressed patients improved by SSRIs compared with depressed patients improved by norepinephrine (NE) reuptake inhibitors, mixed NE/serotonin reuptake inhibitors and placebo. We report that SSRI responders were more anxious-agitated than NE reuptake inhibitor responders, suggesting a preferential efficacy of SSRIs in agitated depression.

Adrenergic Uptake Inhibitors↗
PubMed1995

Neuroleptic associated tardive dyskinesias in young people with psychoses.

BACKGROUND: Apart from ageing, the factors associated with vulnerability to the emergence of tardive dyskinesia are poorly defined. METHOD: Risk factors associated with the presence of a chronic choreic or dystonic disorder were assessed in a cross-sectional comparison of anamnestic and clinical data in a homogeneous group of 64 young psychotic patients (under 40 years of age) on chronic low to moderate doses of neuroleptics. RESULTS: Dyskinetic subjects presented more indirect indicators of occult brain damage, such as a perinatal event or traumatic brain injuries in infancy and early childhood; neurological examination showed more anomalies in dyskinetic patients than in nondyskinetics, with a higher prevalence of facial release reflexes. CONCLUSION: These data may support the hypothesis that occult acquired brain damage is important in the genesis of this 'drug-induced' disorder.

Adult↗
PubMed1994

[Involvement of the basal ganglia in obsessive compulsive disorder: a review].

This article reviews the main clinical indicators linking the basal nuclei to obsessive compulsive disorder (OCD). Various pathologies associated with lesions of the basal nuclei are examined, followed by a review of neuropharmacological, brain imaging and psychosurgical studies. Once the role of the neostriatum in ritualistic behaviours has been clarified, the symptoms of OCD are interpreted based on the hypothesis of a lesion of the striato-orbito-frontal loop.

Basal Ganglia↗
PubMed1993

Organic brain dysfunction and cognitive deficits in young schizophrenic patients with tardive dyskinesia.

Tardive dyskinesia (TD) has been associated with cognitive deficits, especially in older psychiatric patients on neuroleptic medication. This study investigated the relationship between presence of TD, organic brain dysfunction (OBD), and cognitive deficits in young psychiatric outpatients maintained on minimal doses of oral neuroleptics, with anticholinergics prescribed only on as-needed basis. Sixty-four patients, aged 20-39 years, were evaluated for the presence of abnormal movements, localizing and nonlocalizing physical signs, and deficits in memory, ability to shift, and sustained attention. Sixteen patients showed definite signs of TD. Significant associations were found between TD and OBD, and between cognitive deficits and OBD, but not between TD and cognitive deficits. Significant regression predictors of TD were the interaction between OBD and previous dystonia, as well as duration of neuroleptic treatment. These findings suggest that some potential risk factors for TD already identified in the literature also apply to younger patients with relatively shorter exposure to neuroleptics. However, the results indicate that the relationship between movement disorders and cognitive deficits may be more apparent in older patients.

Adult↗
PubMed1993

Early onset of lithium-associated hypothyroidism.

In general practice, psychiatrists are confronted with the difficulty of structuring a rational design for the early detection of hypothyroidism. To determine the period during which a patient receiving lithium is most at risk of developing hypothyroidism, a retrospective study was conducted on the records of 154 patients at two general hospital lithium clinics from January 1980 to August 1991. Forty-two cases of hypothyroidism (clinical hypothyroidism and/or abnormally elevated levels of TSH) were detected. A significant difference was found between the onset of hypothyroidism and age (older patients developed more thyroid dysfunction), but no significant differences were found between thyroid abnormality and sex or diagnostic category and menopausal status, although trends were observed for the two former variables. This longitudinal study is the first to describe an outline of thyroid functioning in terms of the duration of treatment. Lithium-associated hypothyroidism develops most often during the first two years. Of the 42 cases of hypothyroidism, 16 were diagnosed within six months (38%), 23 within the first year (55%), and 31 two years (74%). Since thyroid functioning is an important parameter in the course of affective disorders, its close and frequent monitoring is mandatory during the first two years of treatment.

Adult↗
PubMed1992

[Pathological gambling: literature revue].

This paper summarizes the current literature on pathological gambling. Interest in gambling has been present in every society but treated as an object of sociopolitical or literary interest. It is only from the beginning of this century that psychiatry began to look at pathological gambling, first with Freud and his writing on Dostoïevsky then with other theories like the learning theory, studies on substance dependence, the links with affective syndromes and the psychobiological studies. These studies are presented and discussed. Finally, the authors offer some guidelines for an approach to a pathological gambler.

Behavior, Addictive↗
PubMed1992

[Dysmorphophobia (body dysmorphic disorder)].

This article reviews the historical and terminological origins of dysmorphophobia from Herodotus to today. It explains the differences pointed out by many authors, including the DSM-III-R, between body dismorphic disorder and delusional disorder somatic type, which are referred to as monosymptomatic hypochondriacal psychoses in Europe. Epidemiological data, clinical characteristics and outcome are discussed. Explicative theories and neurobiological, developmental and analytical aspects of body image are presented. The association between body dismorphic disorder and other disorders is analyzed, and treatment possibilities are discussed. The authors suggest that body dismorphic disorder be classified with obsessive compulsive disorder, whatever the intensity of symptomatology, rather than with somatoform or delusional disorder, and treated with serotonin uptake inhibitors or neureptics that have been proven to be effective for the treatment of this disorder, such as pimozide.

Body Image↗
PubMed1992

The dimensional approach to clinical psychopharmacology: a polysemous concept.

The last decade has seen significant progress in the development and specific clinical application of selective psychotropes. The dimensional approach to clinical psychopharmacology views the behavioral targets of psychotropes as phenomena existing on a continuum and as components, in varying degrees, of most psychopathologies. The modern concept of dimension has been used in different contexts. In psychology it has a mathematical sense, whereas in biological psychiatry it is associated more with biological function. This paper reviews these two concepts and the recent models attempting to merge them into one. The heuristic value of the dimensional approach, as well as some of its pitfalls and new avenues of research, are discussed.

Adult↗
PubMed1991

Corpus callosum agenesis and psychosis in Andermann syndrome.

Recent illustrations by cerebral magnetic resonance imaging of anomalies of the corpus callosum in schizophrenics have kindled renewed interest in this association. We studied 62 patients affected by the Andermann syndrome, a polymalformative familial syndrome combining frequent congenital corpus callosum agenesis, mental retardation, psychotic episodes, peripheral neuropathy, and some dysmorphic features. Twenty of 62 patients presenting with psychosis were compared with 20 nonpsychotic patients matched according to sex and age. The psychotic patients presented an atypical psychosis as defined by the Diagnostic and Statistical Manual of Mental Disorders, Third Edition, beginning in postadolescence. No significant relationship was observed between corpus callosum agenesis and psychosis. However, a significant association between posterior fossa atrophy and psychosis was established in our study. Although there are limitations in using cross-sectional data for this purpose, the findings suggest an association between cerebellar anomalies and schizophrenialike syndrome and rule out an implication of developmental callosal defects in such psychiatric disorders.

Adolescent↗
PubMed1989

[Essential arterial hypertension and quality of life. Comparative crossed double-blind study of labetalol and captopril].

The purpose of this multicenter randomised, double-blind and cross-over study was to compare the antihypertensive effects of labetalol (L) and captopril (C) in 42 moderate hypertensive patients (mean age: 52 years). The drugs were given during two 4-weeks periods at the end of which the systolic (SBP) and diastolic blood pressures (DBP) were measured at rest in supine and standing positions. The assessment of the quality of life was realized with 4 scales completed by the practitioner [anxiety, depression, well-being, visual analog scale (VAS)] and 4 scales of auto-assessment completed by the patient [2 VAS, well-being, sub-scale of pleasure]. At the end of the first treatment's period (D28), both drugs had decreased significantly supine SBP and DBP (p less than 0.001), standing DBP (L = p less than 0.01; C = p less than 0.05), while only L lowered supine SBP (p less than 0.01). The cross-over analysis was unable to conclude, due to the number of patients and a significant interaction which reduced its power. Thus the effect of the first treatment's period seemed to influence the efficacy of the second one. The percentages of patients with a controlled BP were respectively: after 4 weeks of treatment, L = 61 p. 100 vs C = 42 p. 100 and at the end of study (D56), L = 67 p. 100 vs C = 64 p. 100.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1988

Substance P and neurokinin A regulate by different mechanisms dopamine release from dendrites and nerve terminals of the nigrostriatal dopaminergic neurons.

Numerous striatal neurons innervating the substantia nigra contain substance P and/or neurokinin A. In contrast to substance P or neurokinin A, little neurokinin B is found in the substantia nigra. This led us to compare the effects of nigral application of these tachykinins on the release of dopamine from dendrites and nerve terminals of nigrostriatal dopaminergic neurons. Experiments were made in halothane-anesthetized cats implanted with one push-pull cannula in the substantia nigra and another in the ipsilateral caudate nucleus [3H]Tyrosine was delivered continuously to each push-pull cannula and the release of newly synthesized [3H]dopamine measured in the superfusate. Unlike substance P or neurokinin A, neurokinin B (10(-8) M) applied for 30 min into the pars compacta of the substantia nigra was without effect on the release of [3H]dopamine from nerve terminals or dendrites. When either substance P (10(-8) M) or neurokinin A (10(-8) M) was applied into the pars compacta, the release of [3H]dopamine from nerve terminals was enhanced. While neurokinin A also stimulated the dendritic release of [3H]dopamine, this was reduced by substance P. At a lower concentration (10(-9) M), neurokinin A induced similar effects to those observed at 10(-8) M whereas substance P (10(-9) M) stimulated moderately [3H]dopamine release from nerve terminals but did not affect the dendritic release of the [3H]amine. When superfused into the pars reticulata, substance P (10(-8) M) still stimulated [3H]dopamine release from nerve terminals but not from dendrites while neurokinin A (10(-8) M) was without effect either in the caudate nucleus or the substantia nigra. Additional experiments were made to determine whether or not substance P (10(-8) M) or neurokinin A (10(-8) M) act directly on nigral dopaminergic neurons when applied into the pars compacta. The effects of substance P on [3H]dopamine release from nerve terminals and dendrites were prevented when 2-amino-6-trifluoromethoxy benzothiazole (10(-5) M), an antagonist of glutamatergic transmission, was applied continuously into the caudate nucleus. In contrast, the stimulatory effects of neurokinin A on [3H]dopamine release from nerve terminals and dendrites were insensitive to 2-amino-6-trifluoromethoxy benzothiazole (10(-5) M). These results suggest that neurokinin A, but not substance P, acts directly on dopaminergic cells. In the light of previous observations, we propose that the effects of substance P on dopaminergic transmission are mediated by a nigro-thalamo-cortico-striatal loop.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1987

[Depressions resistant to tricyclic antidepressive treatment and hypothyroidism].

The relationship between thyroid disorders and depression is well known. This type of endocrine disease is mainly observed in patients with depression resistant to appropriate antidepressor therapy. Three clinical forms of this association may be distinguished: hypothyroidism in a patient with depression but without a previous psychiatric history; a relapse of depression in a manico depressive patient who has developed hypothyroidism; the finding of slight thyroid dysfunction (increased TSH response after injection of TRH) in a patient with depression. The frequency of the association of hypothyroidism and resistant depression underlines the need to perform thyroid function tests in all depressed patients who do not respond normally to appropriate antidepressor therapy. The precise mechanism of the resistance of depressive symptoms to tricyclic antidepressors is unclear. Several arguments point to an effect of triiodothyronine on central noradrenergic receptors. In practice, significant hypothyroidism implies substitute therapy. Minor thyroid dysfunction (abnormal TRH test alone) may require the association of tricyclic antidepressors and thyroid hormone although the indications and precise dosages of this drug association have not been established.

Antidepressive Agents, Tricyclic↗
PubMed1986

In vivo presynaptic control of dopamine release in the cat caudate nucleus--II. Facilitatory or inhibitory influence of L-glutamate.

The local effects of various concentrations of L-glutamate (from 10(-8) M up to 10(-3) M) on the release of [3H]dopamine synthesized continuously from [3H]tyrosine were examined in the caudate nucleus of halothane-anaesthetized cats implanted with push-pull cannulae. When used at a concentration of 10(-8) M or 10(-7) M, L-glutamate stimulated the release of [3H]dopamine from nerve terminals of the nigrostriatal dopamine neurons. This effect was still observed in the presence of tetrodotoxin (5 X 10(-7) M) but it was antagonized by 2-amino 6-trifluoromethoxy benzothiazole (PK 26124) (10(-5) M), an antagonist dopamine nerve terminals. While no significant change in the release of [3H]dopamine was observed with 10(-6) M L-glutamate, higher concentrations (from 10(-5) M to 10(-3) M) of the amino acid produced a long-lasting reduction in the [3H]transmitter release. This latter effect was also antagonized by PK 26124 (10(-5) M) but, unlike that observed with 10(-8) M L-glutamate, it did not persist in the presence of tetrodotoxin (5 X 10(-7) M). On the contrary, a marked stimulation of the release of [3H]dopamine was seen in the presence of this neurotoxin. The reduction in the release of [3H]dopamine produced by 10(-4) M L-glutamate was also antagonized by bicuculline (10(-5) M) and moreover a marked stimulation of [3H]dopamine release took place in the presence of this gamma-aminobutyric acid (GABA) antagonist. Therefore, high concentrations of L-glutamate exerted an inhibitory presynaptic control on [3H]dopamine release which seemed to be indirect and mediated partly by GABAergic neurons. Since a sustained reduction in the spontaneous release of [3H]dopamine was seen in the presence of PK 26124, the corticostriatal glutamatergic neurons appeared to exert a tonic facilitatory presynaptic influence on dopamine release. This effect was important since it represented 40% of the tetrodotoxin-sensitive release of the [3H]transmitter. The direct (stimulatory) and indirect (inhibitory) presynaptic controls on dopamine release mediated by corticostriatal glutamatergic fibres are discussed in light of previous findings and of the anatomical organization of the caudate nucleus.

Animals↗