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C N Pato

Publications and source records attributed to C N Pato.

30 records · Page 2Linked to original sources
PubMed1993

Review of the putative association of dopamine D2 receptor and alcoholism: a meta-analysis.

Eight recent studies have focused on the putative association of the dopamine D2 receptor (DRD2) gene and alcoholism. In this report, these studies are reviewed and the data and findings are examined in a meta-analysis. Four reports find a statistically significant increased risk for alcoholism in subjects carrying the A1 allele and 4 failed to observe a significant increase in risk. Overall, our meta-analysis of the results from all 8 studies supported a statistically significant association between the A1 allele of DRD2 and alcoholism, with an apparent increase in relative risk associated with increased severity of alcoholism. These results must be interpreted cautiously because the A1 allele of DRD2 varies significantly in frequency from one population to another. This variability in the population frequency of the A1 allele could result in an apparent association resulting from unrelated population differences. These findings support the need for carefully designed studies that minimize the ethnic heterogeneity of the subject and control populations.

Alcoholism↗
PubMed1990

Cerebrospinal fluid and plasma monoamine metabolites and their relation to psychosis. Implications for regional brain dysfunction in schizophrenia.

The relationship between central (cerebrospinal fluid [CSF]) and peripheral (plasma) monoaminergic metabolites and psychotic symptoms was examined in 22 drug-free schizophrenic inpatients. The CSF homovanillic acid levels did not differ significantly between patients and normal controls (n = 33). The CSF homovanillic acid levels, however, were negatively correlated with ratings of psychosis and positive symptoms, and the CSF homovanillic acid and 5-hydroxyindoleacetic acid levels correlated negatively with individual deficit symptoms. Stepwise and hierarchical multiple-regression analysis revealed that among monoaminergic measures, only the CSF and plasma homovanillic acid levels contributed significantly to the total Brief Psychiatric Rating Scale and positive symptom variance with negative and positive partial correlations, respectively. Levels of CSF 3-methoxy-4-hydroxyphenylglycol, but not of CSF norepinephrine, were significantly elevated in the schizophrenic patients compared with controls, and plasma 3-methoxy-4-hydroxyphenylglycol levels were positively correlated with negative symptoms. We discuss the potential implications of these findings for a model of dopaminergic dysfunction in schizophrenia involving distinct cortical and subcortical contributions.

Adult↗
PubMed1990

Differential effects of controllable and uncontrollable acute stress on lymphocyte proliferation and leukocyte percentages in humans.

This study examined the effects of a 30-min laboratory stressor on aspects of immune function in 24 men and whether behavioral control over the stressor moderates stress effects. The stressor consisted of mild (2.5 mA) electric shock and loud (100 dB) white noise administered in an unpredictable, intermittent fashion. During stress sessions, only half of the subjects were able to control the stressor. Subjects with control were yoked to subjects who could not control the stressor so that both groups were exposed to identical intensity and duration of noise and shock. Immunologic function was assessed across stress and nonstress conditions by measuring changes in lymphocyte proliferation to concanavalin A (Con A) and phytohemagglutinin (PHA) and by measuring changes in percentages of lymphocytes and their subpopulations, granulocytes, and monocytes. Results revealed that exposure to the uncontrollable stressor altered mood but did not affect immune function. In contrast, exposure to controllable stress did not alter mood but did result in lowered lymphocyte proliferation to Con A. Poststress percentages of monocytes were also lower in subjects exposed to the controllable stressor. Results suggest that acute stress can alter aspects of immune function in humans and underscore the importance of stressor controllability in moderating stress effects on human immunity.

Affect↗
PubMed1989

Advances in the genetics of schizophrenia: editors' introduction.

In view of the rapid advances in the application of molecular genetics to research in schizophrenia, an effort was made to put these studies into a wider perspective. This issue of the Schizophrenia Bulletin is devoted to the expanded presentation of some of the early genetic linkage findings in schizophrenia, and a broader discussion of the impact of these new techniques on schizophrenia research, as well as the limitations of this approach in a complex disorder.

Chromosomes, Human, Pair 5↗
PubMed1989

Prospects for the genetic analysis of schizophrenia.

This issue of the Schizophrenia Bulletin provides a forum for the presentation of early results and speculative hypotheses based on the application of molecular genetic methods for linkage studies in schizophrenia. Contributors were given the freedom to explore the historical and theoretical perspectives on the genetics of schizophrenia. They were also asked to balance their enthusiasm and cautious skepticism at the new suggestions of linkage involving chromosome 5 (Sherrington et al. 1988). In this overview, the epidemiologic evidence for a genetic factor in schizophrenia and recent linkage studies are briefly discussed. In addition, the potential and limitations of different linkage strategies in schizophrenia are examined.

Chromosomes, Human, Pair 5↗
PubMed1989

Smooth pursuit eye movements in schizophrenia: effects of neuroleptic treatment and caffeine.

Abnormal smooth pursuit eye movement (SPEM) has been proposed as a trait marker in schizophrenia. We utilized high resolution infra-red oculography to measure SPEM in 11 neuroleptic-treated schizophrenic patients, 10 drug-free schizophrenic patients, and 11 normals. The most characteristic abnormality was a significant increase in saccadic intrusions during SPEM in schizophrenic patients (p less than .001). SPEM gain was reduced in schizophrenic patients (p less than .005). No significant effects of neuroleptic treatment on SPEM were found, including analysis of seven patients in whom paired data was available. We also measured SPEM prior to and after caffeine ingestion (10 mg/kg) in 10 normals. We found reduced saccadic interruptions as a result of caffeine ingestion compared with placebo (p less than .05). As caffeine has been shown to selectively increase dopaminergic neurotransmission in mesocortical neurons, further study utilizing dopamine agonists during SPEM in schizophrenic patients is warranted.

Adult↗
PubMed1983

Increased membrane permeability to chloride in Duchenne muscular dystrophy fibroblasts and its relationship to muscle function.

Previous studies have suggested an abnormality in Cl- metabolism in Duchenne muscular dystrophy (DMD) fibroblasts. In order to further characterize this abnormality, we have studied 36Cl- distribution and permeability in 11 DMD and 12 normal fibroblast lines. Under steady-state conditions Cl- efflux in fibroblasts is observed to be biphasic, revealing the presence of two major subcellular compartments. Each compartment contains approximately half of the cellular Cl-. The faster of the two observed efflux components is significantly higher in DMD than in control fibroblasts (P less than 0.001). To determine the results of a similar increase in Cl- permeability on skeletal muscle action potentials, we have simulated the effects of increased Cl- conductance on muscle by using a computer model. Effects on the simulated action potential include lower rates of membrane depolarization, lower overpotential, longer duration, and lower input resistance. These effects are similar to those actually observed in DMD muscle.

Action Potentials↗
PubMed1982

Analysis of neurotoxin and mitogen-stimulated sodium transport in human fibroblasts.

Human fibroblasts contain two classes of ouabain-insensitive Na+ channels. One channel is activated by alkaloid neurotoxins in combination with scorpion venom, a response which is similar to that of the voltage-sensitive Na+ ionophore of nerve. The other channel is activated by fetal calf serum, several other mitogenic agents, or low extracellular Ca2+. The nervelike Na+ channel is inhibited by tetrodotoxin but not by amiloride, while the mitogen-stimulated channel is blocked by amiloride but not by tetrodotoxin. The combined effects of neurotoxins and low Ca2+ on Na+ uptake are additive, consistent with the conclusion that these Na+ pathways are different and independent. Studies of Na+ efflux show the presence of two intracellular Na+ compartments. When Na+ flux through the (Na+ + K+)-ATPase pump is inhibited by ouabain, compartment A has a high rate constant of efflux (K1 = 0.30 mn-1) and constitutes 60% of the total cellular Na+. Compartment B, with a markedly smaller efflux constant (k2 = -0.07), contains the remaining 40% of cell Na+. Stimulation of flux through the nervelike channel has a pronounced effect on the rate constants and Na+ content of both compartments (K1 = 0.56, k2 = 0.10), but activation of the mitogenic channel has a pronounced effect only on the rate of efflux from compartment A and on the size of compartment B. A cytoplasmic-nuclear model for the Na+ compartments is presented.

Batrachotoxins↗
PubMed1982

Identification of a biochemical difference between male and female human fibroblasts: implications for the expression of Duchenne muscular dystrophy.

The lysosomal enzyme dipeptidyl aminopeptidase-I (DAP-I) was reduced in Duchenne muscular dystrophy (DMD) fibroblasts to 30% of the level found in age- and sex-matched controls (p less than 0.005). Structure-linked latency, defined as the increase in DAP-I activity caused by disruption of the lysosomal membrane, was also reduced in Duchenne fibroblasts to 70% of normal levels (p less than 0.001). Duchenne carriers and age- and sex-matched control fibroblasts had similar DAP-I activities and latency. However, the similarity of normal and carrier female DAP-I activities was not due to elevation of the carrier female activities to levels similar to normal males, but rather to reduction of all female DAP-I activities to 30% of normal male levels (p less than 0.001). This gave them comparable activities to those of the male DMD cells. One explanation for these unexpected results would require a modification of the genetics of DMD to that of a Y-influenced X-linked model.

Cathepsins↗
PubMedDate not supplied

Comorbidity of obsessive-compulsive and psychotic symptoms: a review.

Co-occurrence of psychotic and obsessive-compulsive symptoms was first reported nearly 70 years ago. This paper reviews published reports from two perspectives: psychotic disorders with obsessive-compulsive symptoms and obsessive-compulsive disorder (OCD) with psychotic symptoms. Older investigations reported a low rate of comorbidity between these two disorders, but more-recent studies, in which systematic diagnostic criteria have been used, have suggested that the rate of co-occurrence of symptoms is higher than was previously thought. The difficulty in diagnosing patients with obsessive-compulsive and psychotic symptoms is reviewed, and the importance of this distinction for treatment and prognosis is discussed. Although the comorbid diagnosis of schizophrenia and OCD, or of OCD and psychotic features, seems to portend a worse prognosis than for either illness alone, the available data suggest that some patients with schizophrenia and OC symptoms may improve with traditional antiobsessional treatment.

Comorbidity↗