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J McGrath

Publications and source records attributed to J McGrath.

At least 91 records · Page 5Linked to original sources
PubMed1995

Month of birth, hemisphere of birth and schizophrenia.

BACKGROUND: To assess quarterly fluctuations in schizophrenia births in a southern hemisphere data set, and to compare the quarterly birth distributions of patients born in the northern and southern hemisphere. METHOD: The month and place of birth of patients with schizophrenia (n = 9348) were extracted from a mental health register. RESULTS: The quarterly birth distribution of patients with schizophrenia differed significantly from the estimated general population distribution in SH-born patients. The quarterly distribution of patient births differed significantly when the two hemispheres were compared. CONCLUSION: These data support the hypothesis that there is a risk for schizophrenia that is related to the time of birth, and which fluctuates across the year.

Geography↗
PubMed1995

Does influenza cause schizophrenia? A five year review.

Over the last five years a body of literature has been generated concerning whether or not prenatal exposure to influenza results in an increased risk of developing schizophrenia in the exposed offspring. The studies are reviewed with respect to the traditional epidemiological criteria that help to define causality. There is a modest degree of consistency in support of an association between the 1957 influenza epidemic--and less so, for influenza epidemics in general--and later schizophrenia. Two cohort studies examining the 1957 epidemic do not support an association. The strength and specificity of the association remain weak. The proposed association draws coherence from the neurodevelopmental hypothesis of schizophrenia. Suggestions are made for future research that could add to our understanding of the putative association between influenza and schizophrenia.

Australia↗
PubMed1994

The Australian multicentre double-blind comparative study of remoxipride and thioridazine in schizophrenia.

A double-blind, randomized study of parallel group design comparing remoxipride and thioridazine (dose range 150-600 mg/day of either drug) was undertaken at 11 Australian centres. A total of 144 patients (remoxipride = 73, thioridazine = 71) with DSM-III-R schizophrenia or schizophreniform disorder commenced the study, and 89 patients (remoxipride = 45, thioridazine = 44) completed the 6 weeks of the trial. The mean daily doses at last rating were 404 mg (remoxipride) and 378 mg (thioridazine). Initial Brief Psychiatric Rating Scale scores decreased by a mean 8.7 points in both remoxipride and thioridazine groups. Equivalent treatment responses were also confirmed by Clinical Global Impression. During the study, sedatives or hypnotics were needed by 68% of the remoxipride patients and 51% of the thioridazine patients. Thioridazine was associated with more postural hypotension, drowsiness, increased sleep, headache, dizziness on rising, dry mouth, sexual dysfunction and weight gain, while remoxipride patients reported more insomnia. There were no differences between remoxipride and thioridazine on dystonia, hypokinesia, dyskinesia, rigidity and akathisia. The results indicate that remoxipride has similar antipsychotic efficacy to thioridazine but causes fewer side effects.

Adolescent↗
PubMed1994

Emotion-related learning in patients with social and emotional changes associated with frontal lobe damage.

A group of patients with damage to the ventral part of the frontal lobes was severely impaired relative to a group of patients without damage in this area (the non-ventral group) in the reversal and in the extinction of simple visual discrimination tests. In these tests they continued to make responses to a previously rewarded stimulus. Patients often reported verbally that the contingencies had changed, but were unable to alter their behaviour appropriately. These impairments occurred independently of IQ or verbal memory impairments. The perseverative touching of a previously rewarded stimulus is consistent with work with non-human primates showing impaired reversal and extinction after orbitofrontal lesions. Performance on these reversal and extinction tests was highly correlated with scores obtained on a behaviour questionnaire, which reflected the degree of disinhibited and socially inappropriate behaviour exhibited by patients. It is suggested that a difficulty in modifying responses, especially when followed by negative consequences, as manifested in these simple laboratory tests, may contribute to the inappropriate behaviour shown in daily life by patients with frontal lobe damage.

Activities of Daily Living↗
PubMed1994

Psychotic inpatients' social class and their first admission to state or private psychiatric Baltimore hospitals.

Social class differences were investigated among patients admitted to public and private psychiatric hospitals. Participants included first admission White psychotic men admitted to Baltimore metropolitan area hospitals between 1983 and 1989. After adjusting for age and diagnosis, patients with low levels of skills/credentials were found to be more likely than patients with higher levels to be admitted to state psychiatric hospitals. These findings underscore the persistence of social class as a determinant of differences in the use of psychiatric care.

Adolescent↗
PubMed1993

Molecular and cytogenetic characterization of 9p- abnormalities.

We report on 2 girls with terminal deletion of the short arm of chromosome 9 with concurrent duplication unrecognizable by routine chromosome studies. The phenotype of the patients was not specifically suggestive of the 9p-syndrome in the absence of trigonocephaly and long philtrum as cardinal manifestations. In addition to psychomotor retardation, their manifestations were mild and include upward slant of palpebral fissures and dolichomesophalangy which are characteristic of del(9p). Chromosome abnormalities were de novo in both cases. The two rearranged chromosomes 9 exhibit similar G-banding patterns and suggested the possible duplication of distal 7p. Fluorescence in situ hybridization (FISH) with a chromosome-7 specific library probe indeed identified that one derivative chromosome 9 was the result of a translocation between chromosomes 7 and 9 [der(9)t(7;9)(p15.3;p24] but failed to detect a signal on the other derivative 9. In the second case, the concurrent abnormality was an inverted duplication of proximal 9p and deletion of distal 9p [inv dup(9)(p13-->p22::p22-->qter)] confirmed by FISH using a chromosome 9 specific library probe. FISH clearly identified the origin of these 2 abnormal chromosomes 9 and provided crucial information for clinical evaluation. We emphasize the importance of utilizing updated cytogenetic and molecular techniques in the precise delineation of subtle or complex abnormalities where there are no useful phenotypic clues.

Abnormalities, Multiple↗
PubMed1993

Female surgeons in the 1990s. Academic role models.

As part of a larger survey of the membership of the Association of Women Surgeons, data were collected to characterize the participation of women in academic surgery and surgical education. Of the 1500 members, 676 (45%) responded, and 318 of these respondents held a faculty appointment. Two hundred thirty-nine of the respondents' practices were based in a university or university-affiliated hospital. This sample was biased toward more academically motivated, upwardly mobile surgeons. Two hundred thirty-six of the respondents believed policies relating to tenure are unfair to women. Four hundred fifty-three respondents reported having role models at some point in their career, half of whom were men. However, only 204 still had access to role models or mentors at the time of the survey. Six hundred thirty respondents believed that female medical students need successful female surgeons as role models.

Adult↗
PubMed1993

Work environment and schizophrenia: an extension of the arousal hypothesis to occupational self-selection.

The present study investigated a possible mechanism underlying the occupational self-selection of future schizophrenic patients prior to their first admission. More precisely, we explored whether schizophrenic patients are more likely than other psychotic patients to work in environments with a low potential for arousal (low complexity environments) in the last full-time job that preceded their hospitalization. All first admissions with psychotic symptoms to 15 hospitals providing inpatient psychiatric services in the Baltimore-Washington area were surveyed during a 6-year period. Patients diagnosed with schizophrenia were compared to patients diagnosed with bipolar disorder and other psychotic disorders to evaluate the suspected association. Study participants were assessed with a modified version of the Diagnostic Interview Schedule. Standard survey questions were used to assess occupational background. A measure based on the dictionary of occupational titles (DOT) was used to estimate the degree of complexity to which patients had been exposed in their last full-time occupation. Data were analyzed using multinomial logistic regression. After adjustment for age, gender, marital status, unemployment, socioeconomic status, hospital type, and physical demands and hazards on the job, patients with schizophrenia were more likely to have been working in low complexity environments in their last full-time jobs (e.g., janitors, gardeners, guards) than patients with bipolar disorder or with other psychotic disorders. Alternative explanations and potential implications regarding which work environments might be best suited to the social behavior of patients with schizophrenia are examined.

Adolescent↗
PubMed1993

General pharmacology of loracarbef in animals.

Loracarbef ((6R, 7S)-7-[(R)-2-amino-2-phenyl-acetamido]-3-chloro-8-oxo-1- azabicyclo [4.2.0]oct-2-ene-2-carboxylic acid, monohydrate, LY 163892, CAS 121961-22-6) is a carbacephem antibiotic targeted for use in the treatment of infectious disease. The potential pharmacological effects of this agent were examined on cardiovascular, respiratory, gastrointestinal, central nervous and autonomic nervous systems. Also examined were local anesthetic activity, effects on platelet aggregation, circulating blood glucose, primary antibody production, renal function, blood coagulation, ocular irritation, and the acute inflammatory response. Doses of 100, 1000, and 2000 mg/kg given by the oral route were selected for most in vivo studies. Concentrations up to 3 x 10(-3) mol/l were used in vitro. Loracarbef was essentially inactive in the tests of central and autonomic nervous system function, platelet aggregation, renal function, blood hemolysis, primary antibody production, blood coagulation, and ocular irritation. It had no local anesthetic activity. At high oral or intravenous doses, representing significant multiples of the therapeutic dose, loracarbef caused changes in gastrointestinal (decrease in gastric acid production and gastric fluid volume; increased biliary output), cardiovascular (increased mean pressure, cardiac output, heart rate, and femoral flow), blood glucose (increased glucose levels), and anti-inflammatory tests (suppressed acute inflammatory response). In summary, loracarbef exhibited minimal activity in these pharmacodynamic studies. These results indicate loracarbef has a low potential to produce adverse effects at therapeutic doses.

Anesthetics, Local↗
PubMed1992

Plasma membrane water permeabilities of human oocytes: the temperature dependence of water movement in individual cells.

Membrane water permeability values were measured in individual fresh human pre-ovulatory oocytes using real time microscopy in a microscope diffusion chamber. The cells were exposed to anisosmotic conditions, their volume responses measured, and from these data the Lp values were computed employing the Kedem-Katchalsky analyses of irreversible thermodynamics. Lp values were measured at four temperatures for each oocyte between 37 degrees C and 10 degrees C, and the temperature-related Arrhenius activation energy (Ea) calculated. It was apparent that individual oocytes exhibited a wide range of Lp values; at 37 degrees C Lp values ranged between 0.33 and 1.80 microns/atm/min. However, each oocyte exhibited the expected inverse linear correlation between Lp and temperature, with high linear correlations (R2 values between 0.73 and 0.96). A mean value for Ea of 8.61 +/- 5.11 Kcal/mol was computed. It is apparent that pre-ovulatory human oocytes express a range of biological diversity in terms of membrane water transport, and this fact needs to be considered when attempting to formulate cryopreservation protocols for storage of these oocytes.

Cell Membrane Permeability↗
PubMed1992

Growth of Babesia bigemina parasites in suspension cultures for vaccine production.

An Australian Babesia bigemina vaccine strain was maintained in suspension culture for 40 days. Parasite growth was compared using two tissue-culture flask sizes (25 and 75 cm2), four gas mixes (2%, 2.5%, 3% and 3.5% O2; 5% CO2; and the balance N2) and four packed blood cell (PCV) volumes (7%, 9%, 13% and 18%). The best continuous parasite yields were obtained from suspension cultures in 75-cm2 flasks at a PCV of 13% and gas mixtures of 2%-3% O2, 5% CO2 and the balance N2. Parasite yields per millilitre of culture medium were 3 times those obtained in microaerophilous stationary-phase cultures. The method has thus far been used for 6 months to produce the Australian requirements for live B. bigemina vaccine.

Animals↗
PubMed1992

Duplication/deficiency mapping of situs inversus viscerum (iv), a gene that determines left-right asymmetry in the mouse.

A recessive mutation in the mouse, situs inversus viscerum (iv), results in randomization of organ position along the left-right body axis: approximately 50% of the progeny of homozygous matings exhibit situs solitus and 50% exhibit situs inversus. Recent studies have established genetic linkage between iv and the immunoglobulin heavy chain gene complex (Igh-C), located on distal mouse chromosome 12. In the present study, we have refined the genetic map location of iv relative to the breakpoint of a reciprocal translocation, T(5;12)31H, involving the telomeric region of chromosome 12 distal to Igh-C and the proximal region of chromosome 5. The translocation results in a large 12(5) derivative chromosome and a small 5(12) derivative chromosome. Because mice with either monosomy or tertiary trisomy for the 5(12) chromosomal region are viable, duplication/deficiency mapping is possible. Deficiency mapping was performed by mating iv/iv homozygotes and T31H heterozygotes. Two animals monosomic for distal mouse chromosome 12 were produced. One of the animals with cytogenetically confirmed monosomy for distal chromosome 12 exhibited situs inversus, indicating that the iv mutation is located at or distal to the T31H breakpoint. For duplication analysis, matings were initially carried out between iv/iv homozygotes and unbalanced T31H animals trisomic for distal chromosome 12. Cytogenetically verified tertiary trisomic progeny were identified and backcrossed with iv/iv homozygotes. The resulting trisomic progeny, 50% of which are expected to carry the iv mutation on both cytogenetically normal copies of chromosome 12, were scored for phenotype.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1992

Risk factors in schizophrenia. Season of birth, gender, and familial risk.

The risk for schizophrenia among first-degree relatives of schizophrenic probands obtained from an epidemiological sample using family history methods was examined to determine whether month of birth of the proband was associated with familial risk. The results of this study of the first-degree relatives of 106 female schizophrenics and 275 male schizophrenics suggested that the relatives of probands born in the months February to May had the highest risk, although the association between month of birth and familial risk among the male probands was present only for those relatives who had onset of schizophrenia before the age of 30.

Adult↗
PubMed1992

Season of birth of siblings of schizophrenic patients.

The hypothesis that mothers of winter-spring-born schizophrenics have an unusual pattern of conception which results in an excess of winter-spring births was tested by studying the distribution of birth-dates of 401 siblings of 120 winter-spring-born schizophrenics and 157 siblings of 59 winter-spring-born controls. All analyses were gender-specific. The results suggest there is no association between the probability of a winter-spring date of birth and being a sibling of a winter-spring-born schizophrenic or control.

Adult↗
PubMed1992

General pharmacology of pergolide in animals. 2nd communication: gastrointestinal, renal and miscellaneous studies.

Pergolide mesylate ((8 beta)-8-[(methylthio)methyl]-6-propylergoline monomethanesulfonate, LY 127809, CAS 66104-23-2) is a novel and potent dopamine agonist marketed for treating the symptoms of Parkinson's disease. The potential secondary pharmacological effects of this agent on the gastrointestinal and renal systems, as well as effects on local anesthesia, hemolysis, platelet aggregation, circulating blood glucose, primary antibody production, and the acute inflammatory response were examined. Pergolide exhibited significant pharmacological effects in gastrointestinal, renal and anti-inflammatory tests at high oral doses. Pergolide was essentially inactive in blood hemolysis, platelet aggregation, primary antibody production and local anesthesia testing. In summary, these studies confirm the pharmacological selectivity of pergolide, and indicate a low potential for secondary pharmacological side effects upon the functions tested at clinically relevant doses.

Anesthetics, Local↗
PubMed1991

Establishment of left-right asymmetry in vertebrates: genetically distinct steps are involved.

Vertebrates exhibit a characteristic pattern of asymmetrical positioning of the visceral organs along the left-right axis. A remarkable developmental step establishes this pattern--primitive organs migrate from symmetrical midline positions of origin into lateral positions. The first organ to pursue such movement is the cardiac tube, which forms a rightward 'D' loop; other organs follow concordantly. The signals and mechanisms directing such organ migration can be studied by analysis of heritable defects of humans and mice. In general, these defects behave as loss-of-function mutations that lead to random determination of visceral situs: for an affected embryo there is an equal chance of correct situs or situs inversus. Distinct phenotypes and patterns of inheritance of these defects suggest that at least three genes are involved in left-right determination, apparently members of a developmental pathway. These genes should be amenable to molecular analysis. We are studying a recessive allele of the mouse called inversus viscerum (iv). Using linkage analysis with cloned restriction fragment length polymorphism markers, we have genetically mapped the iv gene to the distal portion of mouse chromosome 12. We are now pursuing isolation of the gene using methods of positional cloning. Analysis of the iv gene product and of its site and timing of expression may offer clues to how left-right lateralization occurs.

Animals↗