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D Cohen

Publications and source records attributed to D Cohen.

At least 253 records · Page 14Linked to original sources
PubMed1997

[Neuroleptic medication and the risk of tardive dyskinesia: a survey of psychiatrists and general practitioners in Quebec].

UNLABELLED: The incidence of tardive dyskinesia (TD) during the first five years of neuroleptic treatment of adult schizophrenic patients, may rise to 35%. Yet, the prevention of this iatrogenic effect remains a secondary objective for clinicians. This study explored how medication decisions might vary depending on patient characteristics and medical specialty, and to identify correlates of prescribing aimed at the prevention of TD. METHOD: Simulated medication decisions were elicited from 352 psychiatrists and 279 general practitioners in response to 12 brief written descriptions of a male schizophrenic outpatient treated for 5 years with 20 mg/day of haloperidol. Patient age, psychotic symptoms, signs of dyskinesia, and effectiveness of past treatment varied systematically in the descriptions. RESULTS: Every variable except patient age affected decisions. Most physicians reduced doses for stable patients. In cases of active psychosis, decisions were affected by presence of dyskinesia and treatment effectiveness. Psychiatrists were more likely to increase or reduce doses, general practitioners to change medication. Very few physicians opted to cease medication. Younger psychiatrists made the most prudent decisions. CONCLUSIONS: From a tardive dyskinesia prevention perspective, similar prescriptions to older and younger patients are worrying. We need to understand why physicians might believe that older patients require just as aggressive medication regimen as younger patients. Respondents within and between specialties tend make similar simulated decisions, but these do not necessarily reflect recommendations from controlled research on chronic neuroleptic treatment.

Adult↗
PubMed1996

Activation of the human homologue of the Drosophila sina gene in apoptosis and tumor suppression.

Developmentally regulated genes in Drosophila, which are conserved through evolution, are potential candidates for key functions in biological processes such as cell cycle, programmed cell death, and cancer. We report cloning and characterization of the human homologue of the Drosophila seven in absentia gene (HUMSIAH), which codes for a 282 amino acids putative zinc finger protein. HUMSIAH is localized on human chromosome 16q12-q13. This gene is activated during the physiological program of cell death in the intestinal epithelium. Moreover, human cancer-derived cells selected for suppression of their tumorigenic phenotype exhibit constitutively elevated levels of HUMSIAH mRNA. A similar pattern of expression is also displayed by the p21waf1. These results suggest that mammalian seven in absentia gene, which is a target for activation by p53, may play a role in apoptosis and tumor suppression.

Amino Acid Sequence↗
PubMed1996

Elevated cerebrospinal fluid corticotropin-releasing factor in Tourette's syndrome: comparison to obsessive compulsive disorder and normal controls.

Stress- and anxiety-related fluctuations in tic severity are cardinal features of Tourette's syndrome (TS), and there is evidence for involvement of noradrenergic mechanisms in the pathophysiology and treatment of the disorder. To examine further the pathobiology of this enhanced vulnerability to stress and anxiety, we measured central activity of corticotropin-releasing factor (CRF) in patients with TS and the related condition, obsessive compulsive disorder (OCD). Lumbar cerebrospinal fluid (CSF) was obtained in a standardized fashion for measurement of CRF from 21 medication-free outpatients with TS, 20 with OCD, and 29 healthy controls. The TS patients had significantly higher levels of CSF CRF than both the normal controls and the OCD patients. However, there was no difference in CSF CRF between the OCD patients and the normal controls. Group differences in CSF CRF were unrelated to current clinical ratings of depression, anxiety, tics, and obsessive compulsive behaviors. Although the functional significance of this finding remains to be elucidated, these results are consistent with the hypothesis that stress-related neurobiological mechanisms may play a role in the pathobiology of TS.

Adolescent↗
PubMed1996

A yeast artificial chromosome-based map of the region of chromosome 20 containing the diabetes-susceptibility gene, MODY1, and a myeloid leukemia related gene.

We have generated a physical map of human chromosome bands 20q11.2-20q13.1, a region containing a gene involved in the development of one form of early-onset, non-insulin-dependent diabetes mellitus, MODY1, as well as a putative myeloid tumor suppressor gene. The yeast artificial chromosome contig consists of 71 clones onto which 71 markers, including 20 genes, 5 expressed sequence tags, 32 simple tandem repeat DNA polymorphisms, and 14 sequence-tagged sites have been ordered. This region spans about 18 Mb, which represents about 40% of the physical length of 20q. Using this physical map, we have refined the location of MODY1 to a 13-centimorgan interval (approximately equal to 7 Mb) between D20S169 and D20S176. The myeloid tumor suppressor gene was localized to an 18-centimorgan interval (approximately equal to 13 Mb) between RPN2 and D20S17. This physical map will facilitate the isolation of MODY1 and the myeloid tumor suppressor gene.

Base Sequence↗
PubMed1996

Molecular determinants of the clearance function of type C receptors of natriuretic peptides.

Receptor-mediated endocytosis is the cellular mechanism by which type C receptors of natriuretic peptides exert their clearance function. In the present work, performed in recombinant Chinese hamster ovary cells stably transfected with wild type or mutated human kidney C receptors, we determined net endocytic rates (ER) of C receptor-ligand complexes, lysosomal hydrolysis of ligand (125I-labeled native atrial natriuretic factor, ANF1-28), and receptor recycling. Equilibrium ligand binding, immunocytochemistry, and immunoprecipitation were performed to characterize the transfected receptors. The net ER of recombinant wild type C receptors was approximately 6% of occupied receptors internalized per min, and C receptor-mediated lysosomal hydrolysis of ligand amounted to approximately 250% of specifically bound 125I-ANF1-28/h, with efficient recycling of internalized C receptors to the cell surface. Hypertonic sucrose reduced net ER and lysosomal hydrolysis of 125I-ANF1-28 more than 10-fold, indicating that endocytosis occurred via clathrin-coated pits. Total deletion of the cytoplasmic domain also reduced net ER and lysosomal hydrolysis of 125I-ANF1-28 by almost 10-fold, whereas deletion of the terminal 28 amino acids of the cytoplasmic tail led to a 4-fold reduction in these parameters. Replacement of cytoplasmic domain Tyr508 by Ala, or Tyr508 and Phe538 by Ala, reduced net endocytosis and lysosomal hydrolysis of 125I-ANF1-28 by 40-50%. Replacement of extracellular domain Cys473 by Ala impeded the constitutive formation of homodimers and reduced by approximately 50% the net ER and lysosomal hydrolysis of 125I-ANF1-28. These results demonstrate that the cytoplasmic domain of C receptors, Tyr508 within this domain, and constitutive receptor dimerization are the major molecular determinants of the clearance function of C receptors.

Amino Acid Sequence↗
PubMed1996

PHACE syndrome. The association of posterior fossa brain malformations, hemangiomas, arterial anomalies, coarctation of the aorta and cardiac defects, and eye abnormalities.

BACKGROUND: Large facial hemangiomas can have associated central nervous system malformations, particularly the Dandy-Walker posterior fossa malformations. Abnormal arteries, especially those of the central nervous system, coarctation of the aorta, cardiac defects, and unusual ophthalmologic abnormalities can also occur. OBSERVATIONS: We describe two patients with large facial hemangioma, congenital cataracts, and structural arterial abnormalities, particularly of the central nervous system vasculature. One of these infants also had a Dandy-Walker malformation detected on prenatal ultrasound at 12 weeks' gestation, suggesting that this syndrome had its origin during the first trimester of pregnancy. This infant also had a lingual thyroid and developed symptomatic hypothyroidism, possible induced by interferon alfa therapy of her hemangioma. These cases are discussed, along with 41 previously reported cases with similar findings. CONCLUSIONS: Large facial hemangiomas may have a distinctive group of associated arterial, central nervous system, and ophthalmologic anomalies. We propose the acronym PHACE syndrome to emphasize the characteristic findings of this neurocutaneous syndrome: posterior fossa malformations, hemangiomas, arterial anomalies, coarctation of the aorta and cardiac defects, and eye abnormalities.

Abnormalities, Multiple↗
PubMed1996

Measles immunity and response to revaccination of a young adult population in Israel.

In order to evaluate the true immune status and the effect of revaccination on a young adult population, we collected serum samples from 289 military recruits who were vaccinated during an outbreak in 1991. Most vaccinees, age 18-25 years, had apparently been immunized once before as infants. Sera collected just prior to the vaccination and 14 and 28 days afterwards were tested for measles antibodies by hemagglutination inhibition (HI) and enzyme-linked immunosorbent assay (ELISA)-IgM. Before vaccination, 46 (15.9%) of the subjects had no HI antibodies, (< 1:4) and 48 (16.6%) had borderline (1:4) HI titer. Following vaccination, only ten (3.5%) remained negative and 19 (6.6%) had borderline titer. The increase in HI antibody titer was inversely proportional to the prevaccination titer, and 159 subjects (55.0%) showed no increase at all. The geometric mean titer (GMT) rose from 9.14 to 21.47. Among the prevaccination-negative subjects (HI < 1:4) 28 (60.9%) reached a postvaccination titer of > or = 1:8, and eight (17.4%) reached a titer of 1:4. Twelve (26.1%) of the negative subjects seroconverted and developed IgM, 16 (35%) seroconverted without IgM, and 18 (39%) remained negative and did not develop IgM. A group of eight vaccinees with prevaccination titer of > or = 1:4 developed IgM. Some were probably infected by the circulating wild-type virus prior to the vaccination. Thus, a total number of 20 of the 289 subjects studied (6.9%) had true negative preimmune status as judged by the IgM test. However, the vaccination campaign prevented further measles cases, apparently by increasing the population's immunity, particularly in individuals with very low titers or without measles antibodies.

Adolescent↗
PubMed1996

A long-range physical map of human chromosome 21q22.1 band from the YAC continuum.

The human Chromosome (Chr) 21q22.1 region contains several genes for cytokines and neurotransmitters and the gene for superoxide dismutase (mutant forms of which can cause familial amyotrophic lateral sclerosis). A region of approximately 5.8 Mb encompassing D21S82 and the glycinamide ribonucleotide transformylase (GART) loci was covered by overlapping YAC clones, which were contiguously ordered by clone walking with sequence-tagged site (STSs). A total of 76 markers, including 29 YAC end-specific STSs, were unambiguously ordered in this 5.8-Mb region, and the average interval between markers was 76 kb. Restriction maps of the YAC clones with rare-cutting enzymes were simultaneously prepared, and the restriction sites were aligned to obtain a consensus restriction map of the proximal region of the 21q22.1 band. The restriction map made from 44 overlapping YACs contains 54 physically assigned STSs. By integrating the consensus map of the adjacent 1.8-Mb region, we obtained a fine physical map spanning 6.5 Mb of human Chr 21q22.1. This map contains 24 precisely positioned end-specific STSs and 12 NotI-linking markers. More than 39 potential CpG islands were identified in this region and were found to be unevenly distributed. This physical map and the YACs should be useful as a reference map and as a resource for further structural analysis of the Giemsa-negative band (R-band) of Chr 21q22.1.

Base Sequence↗
PubMed1996

Extremely unbalanced: interest divergence and power disparities between clients and psychiatry.

We have tried to show, first, that there exists a wide divergence between the interests of psychiatry and clients: none of the three major models underpinning society's trust in psychiatrists justify confidence that the interests of psychiatry and its clients converge enough to warrant psychiatrists' speaking and acting for clients in the development of the mental health system and its policies. Second, the distribution of power between psychiatrists and clients is highly unequal: the voices of clients have been co-opted or submerged by those of other groups, particularly organized psychiatry and family-dominated advocacy organizations. Our argument is not based on any particular conception of what the "needs" of clients are--we have not claimed to know what they are, nor, indeed, that they are determinable. However, our point is that the mental health system remains with no good theory to support a proposition that needs will be met, leaving no basis upon which to evaluate the system's success. Therefore, insofar as the "purpose" of this system is to meet client needs, we consider the system to be irrational. The numbers of clients and their presumed intensity of interest in mental health policy should have guaranteed them a place of importance in the political processes shaping the mental health system. There are several structural reasons why this has not been the case: client passivity due to the medical model therapeutic context; hesitancy to engage in public action due to the enduring stigma of mental illness; incapacities caused by psychological distress as well as by iatrogenic dysfunction; organizational weakness due to the free-rider problem of voluntary client groups compared with the ability of psychiatry to encourage contributions to its lobbying efforts; marked client disadvantages in obtaining external funding. If we judge one of the positive features of a liberal democracy to be its stability (in that individuals and groups do not need to resort to violence in order to get a fair allocation of society's goods and costs), we need to be watchful. A political system that systematically disadvantages significant segments of society risks alienating them. While such a situation may (temporarily) benefit a small powerful minority, society as a whole will suffer. Goodwin (1989, p. 47) noted that "over the post-war period the state has consistently sought to recognize greater levels of mental illness in the community."

Health Care Reform↗
PubMed1996

Needle-knife sphincterotomy in a tertiary referral center: efficacy and complications.

BACKGROUND: The use of needle-knife sphincterotomy as a method of precut sphincterotomy has been criticized as potentially unsafe. Despite this, a number of tertiary referral centers have reported their successful use of this technique to increase the rate of common bile duct cannulation. METHODS: We assessed the safety and efficacy of needle-knife sphincterotomy in 72 consecutive patients in whom attempts at standard common bile duct cannulation were unsuccessful. Bile duct diameters were correlated to the complication rate. RESULTS: Cannulation of the common bile duct was successful immediately after needle-knife sphincterotomy in 50 patients (67%), and was successful in 17 of the 20 patients who underwent repeat ERCP, for a total cannulation rate of 93%. Eight patients (11%) experienced complications. Retroduodenal perforation during guide wire cannulation attempts and bleeding occurred as frequently as pancreatitis. Small duct size was a risk factor for complications. There was no procedure-related mortality, and all complications were managed medically. CONCLUSIONS: Needle-knife sphincterotomy was effective in facilitating cannulation in patients in whom standard cannulation attempts failed. Limiting guide wire manipulation of the fresh sphincterotomy site and excluding patients with small duct size may further reduce the complication rate.

Adult↗
PubMed1996

Insult, aggression, and the southern culture of honor: an "experimental ethnography".

Three experiments examined how norms characteristic of a "culture of honor" manifest themselves in the cognitions, emotions, behaviors, and physiological reactions of southern White males. Participants were University of Michigan students who grew up in the North or South. In 3 experiments they were insulted by a confederate who bumped into the participant and called him an "asshole". Compared with northerners--who were relatively unaffected by the insult--southerners were (a) more likely to think their masculine reputation was threatened, (b) more upset (as shown by a rise in cortisol levels), (c) more physiologically primed for aggression (as shown by a rise in testosterone levels), (d) more cognitively primed for aggression, and (e) more likely to engage in aggressive and dominant behavior. Findings highlight the insult-aggression cycle in cultures of honor, in which insults diminish a man's reputation and he tries to restore his status by aggressive or violent behavior.

Affect↗
PubMed1996

Survey of CAG/CTG repeats in human cDNAs representing new genes: candidates for inherited neurological disorders.

Expansion of polymorphic CAG and CTG repeats in transcripts is the cause of six inherited neurodegenerative or neuromuscular diseases and may be involved in several other genetic disorders of the central nervous system. To identify new candidate genes, we have undertaken a large-scale screening project for CAG and CTG repeats in human reference cDNAs. We screened 100 128 brain cDNAs by hybridization. We also scanned GenBank expressed sequence tags for the presence of long CAG/CTG repeats in the extremities of cDNAs from several human tissues. Of the selected clones, 286 were found to represent new genes, and 72 have thus far been shown to contain CAG/CTG repeats. Our data indicate that CAG/CTG repeated 10 or more times are more likely to be polymorphic, and that new 3'-directed cDNAs with such repeats are very rare (1/2862). Nine new cDNAs containing polymorphic (observed heterozygote frequency: 0.05-0.90) CAG/CTG repeats have been currently identified in cDNAs. All of the cDNAs have been assigned to chromosomes, and six of them could be mapped with YACs to 1q32-q41, 3p14, 4q28, 3p21 and 12q13.3, 13q13.1-q13.2, and 19q13.43. Three of these clones are highly polymorphic and represent the most likely candidate genes for inherited neurodegenerative diseases and, perhaps, neuropsychiatric disorders of multifactorial origin.

Brain↗
PubMed1996

Walkfree.

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Humans↗