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Biomedical subjects

R Austin

Publications and source records attributed to R Austin.

At least 19 recordsLinked to original sources
PubMed2006

Lifetime suicide rates in treated schizophrenia: 1875-1924 and 1994-1998 cohorts compared.

BACKGROUND: Recent interest in suicide rates in schizophrenia has been considerable. AIMS: To establish the lifetime suicide rate from the pre-chlorpromazine era and to compare this with recent lifetime suicide rates for schizophrenia. METHOD: We have compared suicide and suicide attempt rates for 741 admissions for schizophrenia and 1303 admissions for psychoses to the North Wales Asylum between 1875 and 1924, with first admissions for psychosis in NorthWest Wales between 1994 and 1998. RESULTS: The suicide rate in schizophrenia between 1875 and 1924 was 20 per 100 000 hospital years, a lifetime rate of less than 0.5%. The suicide rate for all psychoses was 16 per 100 000 hospital years. Current rates of suicide for schizophrenia and other psychoses appear 20-fold higher. CONCLUSIONS: These findings point to an increase in suicide rates for patients with schizophrenia.

Adolescent↗
PubMed2004

The sumatriptan/naratriptan aggregated patient (SNAP) database: aggregation, validation and application.

Pooled data from multiple clinical trials can provide information for medical decision-making that typically cannot be derived from a single clinical trial. By increasing the sample size beyond that achievable in a single clinical trial, pooling individual-patient data from multiple trials provides additional statistical power to detect possible effects of study medication, confers the ability to detect rare outcomes, and facilitates evaluation of effects among subsets of patients. Data from pharmaceutical company-sponsored clinical trials lend themselves to data-pooling, meta-analysis, and data mining initiatives. Pharmaceutical company-sponsored clinical trials are arguably among the most rigorously designed and conducted of studies involving human subjects as a result of multidisciplinary collaboration involving clinical, academic and/or governmental investigators as well as the input and review of medical institutional bodies and regulatory authorities. This paper describes the aggregation, validation and initial analysis of data from the sumatriptan/naratriptan aggregate patient (SNAP) database, which to date comprises pooled individual-patient data from 128 clinical trials conducted from 1987 to 1998 with the migraine medications sumatriptan and naratriptan. With an extremely large sample size (>28000 migraineurs, >140000 treated migraine attacks), the SNAP database allows exploration of questions about migraine and the efficacy and safety of migraine medications that cannot be answered in single clinical trials enrolling smaller numbers of patients. Besides providing the adequate sample size to address specific questions, the SNAP database allows for subgroup analyses that are not possible in individual trial analyses due to small sample size. The SNAP database exemplifies how the wealth of data from pharmaceutical company-sponsored clinical trials can be re-used to continue to provide benefit.

Clinical Trials as Topic↗
PubMed2001

Near-field scanner for moving molecules.

We have fabricated using electron beam nanolithography a fixed slit near-field optical scanning device which uses near-field fluorimetry to achieve 200 nm spatial resolution of objects moving over the slits. We explore the basic physics of operating narrow slits in the waveguide cutoff mode and present data from the passage of extended double-stranded DNA molecules passing over the slits as a first example of how this device can be used to do ultrahigh spatial resolution mapping of long polymers.

Algorithms↗
PubMed2000

One-year tolerability and efficacy of sumatriptan nasal spray in adolescents with migraine: results of a multicenter, open-label study.

OBJECTIVE: The objective of this study was to determine the 1-year tolerability and efficacy of sumatriptan nasal spray (NS) at doses of 5, 10, and 20 mg for the treatment of acute migraine in adolescents. METHODS: This was a prospective, multicenter, open-label, 1-year, multiple-attack study. Adolescents (aged 12-17 years) with a > or =6-month history of migraine with or without aura, 2 to 8 moderate or severe migraines per month, and a typical migraine duration of > or =4 hours were eligible for participation. After initial treatment with sumatriptan 10 mg, the dose could be adjusted down to 5 mg or up to 20 mg at the investigator's discretion to optimize tolerability or efficacy. Patients could treat an unlimited number of moderate or severe migraine attacks, provided there was a 24-hour headache-free period between treated attacks and a 2-hour period between doses of sumatriptan NS. A second dose of sumatriptan NS was available for headache recurrence 2 to 24 hours after initial treatment; no more than 2 doses could be used within a 24-hour period. Adverse events, vital signs, electrocardiographic and physical findings, and laboratory variables were assessed. Headache response (reduction of moderate/severe predose pain to mild/no pain) and pain-free response (reduction of moderate/severe predose pain to no pain) were reported by patients 2 hours after dosing. RESULTS: A total of 437 patients treated > or =1 migraine; 3272 total attacks were treated, with 3675 drug exposures (mean, 1.1 dose/attack). Patients had a mean age of 14.1 years, 91% were white, and 53% were female. Seven patients used the 5-mg dose; meaningful conclusions concerning this dose could not be made. Drug-related adverse events were reported in 33% of attacks with the 10-mg dose and 31% with the 20-mg dose; most were related to taste disturbance. Adverse events did not increase with a second dose or over time. Four percent (16/437) of patients withdrew due to drug-related adverse events. One serious adverse event, a facial-nerve ischemic event (10-mg dose), was considered drug related. No drug-related changes in vital signs or electrocardiographic findings were observed. Headache response 2 hours after dosing was reported by 76% of patients taking the 10-mg dose and 72% of those taking the 20-mg dose. Pain-free response 2 hours after dosing was reported by 43% and 40% of patients in the 10- and 20-mg groups, respectively. CONCLUSIONS: Based on these results, sumatriptan NS at doses of 10 and 20 mg was well tolerated and effective in the 1-year treatment of multiple migraine attacks in adolescents.

Administration, Intranasal↗
PubMed2000

A randomized, double-blind, placebo-controlled study of sumatriptan nasal spray in the treatment of acute migraine in adolescents.

OBJECTIVE: To compare the efficacy and tolerability of sumatriptan nasal spray (NS; 5 mg, 10 mg, and 20 mg) with placebo for the treatment of acute migraine in adolescents. METHODS: A randomized, double-blind, placebo-controlled, single-attack study was conducted in 653 US adolescents (12-17 years of age). Patients with at least a 6-month history of migraine, who met International Headache Society criteria for migraine (with or without aura) were eligible for participation. Headache relief 2 hours postdose, complete relief, presence or absence of associated symptoms, headache recurrence, and use of rescue medications were recorded. The primary efficacy endpoint was headache relief 2 hours postdose sumatriptan NS (20 mg) versus placebo. Safety and tolerability were assessed by examining adverse events, changes in electrocardiograms, vital signs, physical examinations, and clinical laboratory tests. RESULTS: Headache relief 1 hour postdose was significantly greater for patients using 10 mg (56%) and 20 mg (56%) of sumatriptan NS compared with placebo (41%). Headache relief 2 hours postdose was significantly greater for patients using 5 mg of sumatriptan NS (66%) compared with placebo (53%), and approached statistical significance for 20 mg (63%) compared with placebo (53%). Complete relief 2 hours postdose was significantly greater for patients using 20 mg of sumatriptan NS compared with placebo (36% vs 25%, respectively). Each dose of sumatriptan (5 mg, 10 mg, and 20 mg) was superior to placebo with respect to the cumulative percentages of patients first reporting headache relief within 2 hours of dosing (Kaplan-Meier). The sumatriptan 20-mg dose was superior to placebo with respect to the cumulative percentages of patients first reporting complete relief within 2 hours of dosing (Kaplan-Meier). Photophobia and phonophobia were significantly reduced 2 hours postdose for sumatriptan NS (20 mg), compared with placebo (36% vs 48% and 25% vs 44%, respectively). Taste disturbance was the most commonly reported adverse event (2%, 19%, 30%, and 26% for placebo, 5 mg, 10 mg, and 20 mg, respectively). No drug-related serious adverse events or clinically relevant changes in laboratory parameters, electrocardiograms, or vital signs were reported. CONCLUSIONS: Sumatriptan NS is effective and well-tolerated for the treatment of acute migraine in adolescents, with the 20-mg dose providing the best overall efficacy and tolerability profiles.

Acute Disease↗
PubMed1998

Post-infarction heart failure in the rat is associated with distinct alterations in cardiac myocyte molecular phenotype.

The myocardial molecular and cellular responses to hemodynamic and other hypertrophic stimuli have been characterized extensively, but less is known of the alterations in gene expression during the evolution of heart failure following myocardial infarction, and specifically those affecting the cardiac myocytes. Therefore, the present study was undertaken to test the hypothesis that post-infarction heart failure and remodeling in the rat is associated with a distinct myocyte molecular phenotype. To address this question, hemodynamic measurements were performed in vivo; and myocytes isolated from the non-infarcted myocardium 1 day, 1 week, and 6 weeks post-coronary artery ligation in post-infarct rats and sham controls. Myocyte size, mRNA levels for immediate early genes, contractile proteins, and sarcoplasmic reticulum Ca2+-ATPase (SERCA) and phospholamban were assayed by Northern analyses, and SERCA and phospholamban proteins were examined by Western blotting. Hemodynamic evidence of heart failure was present at all post-infarct time points. Myocyte size was increased significantly at 6 weeks. c-myc expression was increased at 1 day and 1 week in the infarcted rats, but returned to baseline by 6 weeks. Atrial natriuretic peptide and VEGF mRNAs were elevated at 1 and 6 weeks. Both beta-myosin heavy chain and skeletal alpha-actin expression were increased at all post-MI time points. In contrast, neither changes in the expression of the calcium-handling proteins (SERCA and phospholamban) were not observed, nor was there a change in TGFbeta1 or TGFbeta3. These results demonstrate that in rats with post-MI heart failure, there was an immediate induction of the fetal/embryonic transcriptional gene program which preceded myocyte hypertrophy and appeared to persist longer than in pressure-overload models. In further contrast to pressure-overload, expression of sarcoplasmic reticulum Ca2+-ATPase and phospholamban, was not altered despite a comparable degree of cellular hypertrophy and more severe hemodynamic decompensation. These findings suggest that there may be important differences in the regulatory mechanisms underlying these two forms of myocardial hypertrophy and heart failure.

Actins↗
PubMed1998

Lithium and maintenance electroconvulsive therapy.

This clinical report describes the successful use of a combination of lithium carbonate and maintenance electroconvulsive therapy (ECT) in the treatment of severe bipolar depression. The patient was initially taken off the lithium and given a course of ECT with remarkable improvement in symptoms. He subsequently underwent maintenance ECT, during which lithium was restarted without any side effects. Rating scales were used to assess memory, depression, and mental status. This case suggests that the overlap of the two treatments may be especially beneficial when the plan is to taper maintenance ECT while continuing pharmacotherapy.

Bipolar Disorder↗
PubMed1995

Estimating the value of a generic quality-of-life measure.

In this paper, data from a clinical trial of a new antiviral agent for treating patients with zoster are used to answer the following question: Does the Nottingham Health Profile (NHP) add to the information obtained from the clinical measures? Three ways in which the NHP could add information are measured. First, Cox's regression analysis is used to determine whether health-related quality-of-life scores obtained at diagnosis give information about disease prognosis. Second, changes in mean NHP scores in different dimensions are computed after pain resolution to determine whether NHP scores provide more sensitive indicators of disease resolution. Third, linear regression is used to determine whether the impacts of disease on quality of life are measured adequately by the clinical parameters. These analyses show that use of the physical mobility and energy dimensions of the NHP increases understanding of disease prognosis; demonstrates the continuing impact of zoster on patients' sleep patterns and energy levels, disease symptoms not included as clinical measures, that persist after the cessation of zoster-associated pain; and gives a measure of the impact of zoster on the patient, which includes unmeasured and measured levels of severity.

Acyclovir↗
PubMed1994

A retrospective-cohort study of occupational exposure to hexavalent chromium.

A retrospective cohort study was conducted to examine the risk of mortality, cancer, and other adverse health outcomes, at the United States' largest chromate chemicals manufacturing facility in Castle Hayne, North Carolina. This facility, built in 1971, was designed to reduce the high levels of chromium exposure found at most older facilities. Exposure assessment was based on analysis of more than 5,000 personal breathing zone samples collected over a 15-year period. A questionnaire was used to collect relevant occupational, medical, smoking, and other information from current and former employees. Analysis of the cohort's mortality experience found no substantial departures from that expected based on external comparisons, although evidence of a healthy worker effect was observed. Internal cohort analyses were limited by relatively small numbers; however, a subgroup of employees who transferred from older facilities was found to have higher risks of mortality (odds ratio = 1.27 for each 3 years of previous exposure; 90% confidence interval (CI) = 1.07-1.51) and cancer (odds ratio = 1.22 for each 3 years of previous exposure; 90% CI = 1.03-1.45). While this subgroup represented only 11% of the individuals in this study, they accounted for 46% (6/13) of all observed cancers (excluding skin cancers) and 60% (3/5) of lung cancers. There was no increased risk of mortality or cancer among employees who worked only at the newer facility. As an etiologic research study, the results are limited by the relatively small number of subjects and short follow-up; nevertheless, the findings can be used to design and implement a prospective surveillance system for monitoring the health of chromate production workers.

Carcinogens, Environmental↗
PubMed1994

The Nottingham Health Profile as a measure of quality of life in zoster patients: convergent and discriminant validity.

The main symptoms of zoster, a disease caused by the reactivation of the varicella zoster virus (that causes chicken-pox) are: rash, associated with pain, burning, or itching, and pain that outlasts the rash sometimes by months or years. The uncomfortable and long-lasting symptoms of herpes zoster are likely to compromise the patient's quality of life. However, the impact of zoster on health-related quality of life has not previously been measured directly. Recent papers have demonstrated the ability of generic measures to discriminate among patients with different clinical symptoms. In this paper, we demonstrate the convergent validity for zoster of a generic measure, the Nottingham Health Profile (NHP), by measuring its correlation with rash progression, pain levels, and pain medications. The discriminant validity of the NHP was demonstrated by its ability to distinguish between different levels of pain severity. The NHP dimensions most highly correlated with the pain measures, were pain (0.42-0.50), energy (0.34-0.38) and sleep (0.32-0.38). The NHP scores in all six dimensions show large differences at different levels of pain severity that are statistically significant. These results demonstrate the NHP's validity as a measure of health-related quality of life in zoster patients.

Health Status Indicators↗
PubMed1992

Effects of prolactin on secretion and synthesis of human chorionic gonadotropin in human term placentas in vitro: short-term increase in secretion, followed by medium-term suppression of synthesis and secretion.

We studied the influence of human prolactin on the secretion and de novo synthesis of human chorionic gonadotropin (hCG) in the human term placenta in culture. Placental tissue from 14 patients with uncomplicated pregnancies and deliveries was prepared mechanically, with addition of a Percoll gradient step. hCG levels were determined in the culture media and in the cytosolic fraction of cells by means of an enzyme immunoassay with coated beads. The amount of newly synthesized hCG was measured by the extent of incorporation of 35S-methionine into the hCG molecule. Our results showed that human prolactin had two different effects in vitro: between 1/2 and 1 h, prolactin slightly increased secretion of hCG into the culture medium without affecting de novo synthesis; after 2 h, prolactin began to cause a significant decrease in both secretion and de novo synthesis of hCG over several hours. It appears that both effects are receptor mediated, for ovine prolactin failed to produce any response. We conclude that prolactin is one of the main factors regulating the synthesis and secretion of hCG in the human trophoblast at term.

Animals↗
PubMed1991

Hippocampal pyramidal cell disarray in schizophrenia as a bilateral phenomenon.

In a continuing quantitative study of hippocampal cell orientation in schizophrenic subjects and nonschizophrenic control subjects, a pattern of right hemispheric cell disorganization in schizophrenic subjects, as robust as that previously described in the left hemisphere, was shown. The study was based on tissue from 11 schizophrenic and seven approximately age-matched control subjects from a Veterans Administration Medical Center. Using a new measuring technique that proved complementary and superior to the method formerly used, we determined the axes of orientation for approximately 10,800 neurons. A significant difference in cell disorganization was found between schizophrenic and control subjects. From separate analyses of the interface zones among the various hippocampal cell sectors, this difference was found to be significant at the interfaces between cornu ammonis zones 1 and 2 and zones 2 and 3. Analysis of the pattern of disorganization numbers suggests a bimodal distribution in which the cell orientation values of one group of schizophrenic subjects overlap those of the nonschizophrenic control group, while the cell orientation values of a second group significantly exceed those of the control population. Although some recent studies have suggested that schizophrenia may be related exclusively to the left hemisphere, the results of this study indicate that schizophrenia-related structural changes involve the right hemisphere as well. Thus, schizophrenia may be a bilateral rather than unilateral disorder.

Adult↗
PubMed1991

Pulmonary changes in congenital syphilis.

Three of seven infants afflicted with congenital syphilis at our institution in the past five years showed diffuse pulmonary infiltrates. These persisted long after adequate antibiotic treatment of the primary infection. Review of pathologic literature suggests these infiltrates represent pulmonary immaturity, extramedullary hematopoiesis, and interstitial scarring.

Humans↗