Search PubMed⌕ Search

Biomedical subjects

S Geisler

Publications and source records attributed to S Geisler.

At least 19 recordsLinked to original sources
PubMed1999

Predictors of relapse following response from a first episode of schizophrenia or schizoaffective disorder.

BACKGROUND: We examined relapse after response to a first episode of schizophrenia or schizoaffective disorder. METHODS: Patients with first-episode schizophrenia were assessed on measures of psychopathologic variables, cognition, social functioning, and biological variables and treated according to a standardized algorithm. The sample for the relapse analyses consisted of 104 patients who responded to treatment of their index episode and were at risk for relapse. RESULTS: Five years after initial recovery, the cumulative first relapse rate was 81.9% (95% confidence interval [CI], 70.6%-93.2%); the second relapse rate was 78.0% (95% CI, 46.5%-100.0%). By 4 years after recovery from a second relapse, the cumulative third relapse rate was 86.2% (95% CI, 61.5%-100.0%). Discontinuing antipsychotic drug therapy increased the risk of relapse by almost 5 times (hazard ratio for an initial relapse, 4.89 [99% CI, 2.49-9.60]; hazard ratio for a second relapse, 4.57 [99% CI, 1.49-14.02]). Subsequent analyses controlling for antipsychotic drug use showed that patients with poor premorbid adaptation to school and premorbid social withdrawal relapsed earlier. Sex, diagnosis, obstetric complications, duration of psychotic illness before treatment, baseline symptoms, neuroendocrine measures, methylphenidate hydrochloride challenge response, neuropsychologic and magnetic resonance imaging measures, time to response of the initial episode, adverse effects during treatment, and presence of residual symptoms after the initial episode were not significantly related to time to relapse. CONCLUSIONS: There is a high rate of relapse within 5 years of recovery from a first episode of schizophrenia and schizoaffective disorder. This risk is diminished by maintenance antipsychotic drug treatment.

Adolescent↗
PubMed1999

Predictors of treatment response from a first episode of schizophrenia or schizoaffective disorder.

OBJECTIVE: This study examined the treatment response of patients with first-episode schizophrenia and schizoaffective disorder and potential predictors of response. METHOD: First-episode patients were assessed on measures of psychopathology, cognition, social functioning, and biological parameters and treated according to a standardized algorithm. RESULTS: One hundred eighteen patients (52% male, mean age 25.2 years) entered the study. The cumulative percentage of patients responding by 1 year was 87%; the median time to response was 9 weeks. The following variables were significantly associated with less likelihood of response to treatment: male sex, obstetric complications, more severe hallucinations and delusions, poorer attention at baseline, and the development of parkinsonism during antipsychotic treatment. Variables not significantly related to treatment response were diagnosis (schizophrenia versus schizoaffective disorder), premorbid functioning, duration of psychotic symptoms prior to study entry, baseline disorganization, negative and depressive symptoms, baseline motor function, akathisia and dystonia during treatment, growth hormone and homovanillic acid measures, psychotic symptom activation to methylphenidate, and magnetic resonance measures. CONCLUSIONS: Patients with first-episode schizophrenia and schizoaffective disorder have high rates of response to antipsychotic treatment; there are specific clinical and pathobiologic predictors of response.

Adult↗
PubMed1997

Differential distribution of five members of the matrix metalloproteinase family and one inhibitor (TIMP-1) in human liver and skin.

Matrix metalloproteinases represent a family of zinc-dependent proteolytic enzymes thought to be involved in normal and disease-related tissue remodeling processes. Increasing information about these enzymes is becoming available concerning their primary sequences, regulation at the mRNA level, activation of proenzymes, and modulation of enzyme activity by tissue inhibitors. In contrast, their morphological distribution and biological functions in normal tissues are poorly understood. In the present report, the comparative distribution of five members (gelatinase-A, gelatinase-B, matrilysin, stromelysin-1, and stromelysin-3) of the matrix metalloproteinase family and of one inhibitor (TIMP-1) has been morphologically analyzed in human liver and skin with the aid of new monospecific antibodies. Because of their common designation as matrix proteinases, these enzymes might have been expected to be distributed throughout these tissues, or at least in the connective tissue. However, each member of the family produces a highly specific pattern, staining structures such as arteriolar smooth muscle cells, myoepithelial cells in secretory portions or the luminal lining in excretory ducts of dermal sweat glands, liver bile canaliculi, or structures surrounding peripheral nerve axons. No reactivity is detected in rat tissues.

Animals↗
PubMed1997

Absence of p21 expression is associated with abnormal p53 in human breast carcinomas.

The p53 tumour-suppressor gene is important in the regulation of cell growth and apoptosis, and loss of functional wild-type activity may be associated with tumour formation and resistance to therapy. Differentiation of functionally normal wild-type protein from mutant or abnormal protein remains difficult using either immunohistochemical assays or mutational DNA sequencing. p21(WAF1/CIP1) (p21) is induced by wild type p53 and plays an important role in promoting cell cycle arrest. To test the hypothesis that p21 protein expression may act as a downstream marker of tumours from patients with locally advanced breast cancer before treatment with doxorubicin, pretreatment p53 status had been characterized in 63 tumours by p53 protein immunostaining and DNA mutational analysis. There was a significant association between immunostaining for p53 and the presence of p53 mutations (P = 0.01). Of 56 patients available for determination of p21, 31 (55%) expressed p21 protein. Twenty-eight out of 31 patients (90%) positive for p21 had low negative p53 protein expression, whereas only 3 of 13 patients (23%) with high p53 expressed p21 (P = 0.009). No association was seen between p21 protein expression and p53 mutations (P = 0.24). The combination of p53 and p21 immunostaining results improved the specificity of the immunostaining but at a cost of significant reduction in sensitivity. Immunohistochemical assessment of p21 protein expression is inversely associated with abnormal p53 protein in human breast cancer. The detection of p21 protein expression in combination with p53 protein expression did not improve the ability of immunohistochemistry (IHC) to differentiate between normal and mutant p53 protein.

Adult↗
PubMed1997

Differential effect of carbamazepine and valproate monotherapy on plasma levels of oestrone sulphate and dehydroepiandrosterone sulphate in male epileptic patients.

Steroid sulphates such as oestrone sulphate (OE1S) and dehydroepiandrosterone sulphate (DHEAS) have been suggested to be of biological importance in different disease states such as breast cancer and atherosclerosis. Previous studies have shown that drugs such as aminoglutethimide and rifampicin that induce P450-dependent mixed-function oxygenases selectively suppress plasma OE1S levels. The aim of this study was to evaluate the influence of treatment with carbamazepine, an antiepileptic drug known to stimulate mixed-function oxygenases, on plasma levels of OE1S and DHEAS. We measured plasma OE1S and DHEAS together with other plasma oestrogens and androgens in male epileptic patients before and during carbamazepine monotherapy. Patients treated with valproate monotherapy acted as a control group. Treatment with carbamazepine decreased plasma OE1S levels from a mean value of 810.8 to 411.6 pmol/l (mean suppression to 50.7% of pretreatment levels, P < 0.001). Similarly, the ratio of OE1S to OE1 fell to 59.9% of pretreatment levels (P < 0.001)). DHEAS decreased from a mean level of 4.9 mumol/l before treatment to 3.0 mumol/l during carbamazepine therapy (mean reduction to 62.7% of pretreatment levels (P < 0.001), while the ratio of DHEAS to DHEA fell to 63.0% of pretreatment values (P < 0.01). No significant change in plasma levels of the other oestrogens or androgens measured was observed. Treatment with valproate caused a slight decrease in FSH levels (P < 0.05), but no change in any of the other hormones measured was observed. Studies are warranted to evaluate the possible effects of long-term treatment with carbamazepine on the risk of developing endocrine-sensitive tumours and cardiovascular disease and also the possible effects of alterations in plasma DHEAS on epileptic activity.

Adolescent↗
PubMed1996

Incidence and correlates of tardive dyskinesia in first episode of schizophrenia.

BACKGROUND: There is controversy over whether tardive dyskinesia (TD) is solely a consequence of antipsychotic drug treatment or in part may reflect an intrinsic aspect of the disease process. Pathophysiologic factors could, independently or in concert with drug effects, lead to the development of dyskinetic signs. METHODS: We studied prospectively 118 patients in their first episode of psychosis who were treatment-naive or had less than 12 weeks of antipsychotic drug exposure at study entry. Patients received standardized antipsychotic drug treatment and were evaluated for up to 8 1/2 years with regular assessments of psychopathologic signs and symptoms and side effects. RESULTS: The cumulative incidence of presumptive TD was 6.3% after 1 year of follow-up, 11.5% after 2 years, 13.7% after 3 years, and 17.5% after 4 years. Persistent TD had a cumulative incidence of 4.8% after 1 year, 7.2% after 2 years, and 15.6% after 4 years. Taken individually, both antipsychotic drug dose, entered as a time-dependent covariate, and poor response to treatment of the first psychotic episode were significant predicters of time to TD. When antipsychotic drug dose and treatment response were examined together, treatment responders had significantly lower hazards for presumptive TD than nonresponders (hazard ratio, 0.29; 95% confidence interval, 0.09 to 0.97). Dose was a trend-level predicter, with each 100-mg chlorpromazine equivalent unit increase in dose associated with a 5% increase in the hazard of presumptive TD (hazard ratio, 1.05; 95% confidence interval, 0.99 to 1.11). CONCLUSION: Poor response to the treatment of a first episode of psychosis and, to a lesser extent, antipsychotic drug dose are important factors in the development of TD. This suggests that there may be a disease-related vulnerability to TD manifest with antipsychotic drug exposure. Potential pathophysiologic factors might include neurodevelopmentally induced structural neuropathologic characteristics, sensitization of nigrostriatal dopamine neurons, and the induction of glutamatergically mediated neurotoxic effects.

Adult↗
PubMed1996

Psychobiologic correlates of treatment response in schizophrenia.

In studies conducted on largely treatment naive patients in their first episode of psychosis, we have found that treatment outcome is quite good and that most patients recover or at least achieve a substantial degree of symptom remission. However, over the course of their illness and in the context of subsequent psychotic episodes, they may experience some decrease in their treatment response from illness progression. In addition, the heterogeneity of treatment outcome is associated with specific clinical (gender, primary negative symptoms of the deficit state, duration of psychosis) and biological variables (pHVA, ventricular volume). It is unclear whether these variables represent aspects of discrete subtypes of schizophrenia or dimensional measures of pathology within the broad context of a unitary disease entity.

Follow-Up Studies↗
PubMed1996

Specific P53 mutations are associated with de novo resistance to doxorubicin in breast cancer patients.

The mechanisms causing resistance to chemotherapeutic drugs in cancer patients are poorly understood. Recent evidence suggests that different forms of chemotherapy may exert their cytotoxic effects by inducing apoptosis. The tumor suppressor gene P53 has a pivotal role inducing apoptosis in response to cellular damage. In vitro investigations have shown intact p53 to play a critical role executing cell death in response to treatment with cytotoxic drugs like 5-fluorouracil, etoposide and doxorubicin. Recently, mutations in the P53 gene were found to confer resistance to anthracyclines in a mouse sarcoma tumor model, and overexpression of the p53 protein (which, in most cases, is due to a mutated gene) was found to be associated with lack of response to cisplatin-based chemotherapy in non-small cell lung cancer. Previous studies have shown mutations in the P53 gene or overexpression of the p53 protein to predict a poor prognosis, but also a beneficial effect of adjuvant radiotherapy or chemotherapy in breast cancer. In this study we present data linking specific mutations in the P53 gene to primary resistance to doxorubicin therapy and early relapse in breast cancer patients.

Adult↗
PubMed1996

Primary systemic treatment with weekly doxorubicin monotherapy in women with locally advanced breast cancer; clinical experience and parameters predicting outcome.

Sixty-three patients (median age 64 years) with locally advanced breast cancer (T3, T4 and/or N2) were treated with primary 'neoadjuvant' chemotherapy given as weekly doxorubicin monotherapy (14 mg/m2 per dose). Seven patients had solitary distant metastasis at the time of diagnosis. Twenty-eight patients (45%) achieved 'partial response' to primary chemotherapy. Twenty-nine patients (46%) had 'stable disease', and 6 patients (9%) had 'progressive disease' during treatment. Following chemotherapy, 52 patients were subjected to surgery and another 4 patients had surgery performed after radiotherapy. Surgery was considered impossible in only three patients. After a median observation time of 23 months, local recurrences were observed in 2 patients, one with progressive disease and one with stable disease during chemotherapy. Univariate analyses revealed that large tumour size, high histological grade and high mitotic frequency were associated with poor primary response to chemotherapy. Recent studies have demonstrated a correlation between p53-mutations and chemotherapy response.

Adult↗
PubMed1995

Prevalence and clinical correlates of extrapyramidal signs and spontaneous dyskinesia in never-medicated schizophrenic patients.

OBJECTIVE: This study assessed the prevalence of extrapyramidal signs and spontaneous dyskinesia in neuroleptic-naive, first-episode schizophrenic patients and examined the clinical correlates. METHOD: In a prospective study of the psychobiology of schizophrenia, the authors examined 89 neuroleptic-naive patients for the presence of extrapyramidal signs by using the Simpson-Angus Rating Scale and for dyskinesia by using the Tardive Dyskinesia Rating Scale. RESULTS: Fifteen patients (16.9%) had extrapyramidal signs, but only one had spontaneous dyskinesia at baseline. Presence of extrapyramidal signs was correlated with more negative symptoms and poorer treatment outcome that was reflected in a longer time to and lower level of remission. There was no correlation of spontaneous extrapyramidal signs with age of patient, age at onset of psychotic symptoms, or baseline psychopathology. There was no difference between patients with and without spontaneous extrapyramidal signs in terms of the subsequent development of persistent tardive dyskinesia, but the patients with spontaneous extrapyramidal signs were more likely to develop parkinsonian side effects after 8 weeks of antipsychotic treatment. CONCLUSIONS: Extrapyramidal signs are present in a proportion of neuroleptic-naive, first-episode schizophrenic patients, which suggests an involvement of these signs in the schizophrenic process that probably reflects basal ganglia pathology. The presence of spontaneous extrapyramidal signs seems to have prognostic significance insofar as it is linked to a poorer outcome and longer time to remission. Spontaneous dyskinesia appears to be a relatively rare finding.

Adolescent↗
PubMed1995

Gender differences in onset of illness, treatment response, course, and biologic indexes in first-episode schizophrenic patients.

OBJECTIVE: Gender differences in onset of illness, response to treatment, course, and biologic measures have been consistently reported in patients with chronic schizophrenia. Patients with first-episode schizophrenia were examined to determine whether gender differences also occur in these patients. METHOD: Fifty-four neuroleptic-naive schizophrenic patients (29 men and 25 women) were studied beginning in an initial stage of the first hospitalization for psychosis while undergoing treatment with a standardized medication regimen. Before antipsychotic drug treatment and during 1 year of follow-up each patient was rated on the Schedule for Affective Disorders and Schizophrenia--Change Version (psychosis and disorganization items), Scale for the Assessment of Negative Symptoms, Clinical Global Impression, modified Simpson Tardive Dyskinesia Scale, and Simpson-Angus Rating Scale for extrapyramidal side effects. Methylphenidate challenge testing was done at study entry. Plasma neuroleptic, homovanillic acid (HVA), and prolactin levels were determined weekly for the first 6 weeks. RESULTS: The female schizophrenic patients had a later onset and better treatment response than the men. Plasma HVA levels at baseline and week 1 and changes in prolactin levels from baseline to weeks 1 through 6 were greater among the women. CONCLUSIONS: Gender differences in onset and degree of treatment response in first-episode schizophrenic patients are similar to those of chronic patients and are apparent at early stages of the illness. The greater pharmacologic responsivity of the female patients, as indicated by the neuroendocrine results, is consistent with the gender difference in degree of symptom improvement with medication.

Adolescent↗
PubMed1994

Methylphenidate response, psychopathology and tardive dyskinesia as predictors of relapse in schizophrenia.

Despite the proven efficacy of acute and maintenance pharmacotherapy in schizophrenia, practical methods for identifying patients who require continuous treatment to prevent relapse have not been established. We hypothesized that a pathologic overactivity of mesolimbic and mesocortical dopamine neural systems, that mediates positive psychotic symptoms in the acute phase of the illness, persists in some outpatients who are vulnerable to relapse despite appearing clinically stable. To test and determine if putative measures of central nervous system dopamine activity predict outcome, 41 stable outpatients receiving neuroleptic maintenance treatment underwent provocative tests with methylphenidate in a randomized double-blind placebo controlled design in which behavioral, neuromotor, biochemical, and cardiovascular responses were measured. Patients were then withdrawn from medication and monitored for 52 weeks, or until relapse. The results indicate that psychotic symptoms and their activation by methylphenidate, and the presence of tardive dyskinesia are associated with each other and with a higher risk of relapse. These findings partially support our hypothesis and offer potentially useful measures for the identification of candidates for reduced dose neuroleptic maintenance treatment strategies in schizophrenia.

Adolescent↗
PubMed1993

Time course and biologic correlates of treatment response in first-episode schizophrenia.

OBJECTIVE: To examine the course and potential predictors of treatment response in the early phase of schizophrenia. DESIGN: Prospective study of an inception cohort. SETTING: Psychiatric division of an academic medical center with a suburban metropolitan catchment area. PATIENTS AND INTERVENTION: Seventy first-episode patients who had undergone four biologic assessment procedures (brain magnetic resonance imaging, behavioral response to methylphenidate hydrochloride, growth hormone levels, eye tracking) were treated with a standardized antipsychotic drug protocol until recovery. Response was measured in terms of psychopathology and degree of remission. RESULTS: Using survival analysis, the proportion of patients remitting by 1 year was estimated at 83%. Mean and median times to remission were 35.7 weeks and 11 weeks, respectively. No baseline demographic or psychopathologic measure significantly predicted time to or level of remission. However, males tended to be nonresponders to treatment and have diagnoses of schizophrenia rather than schizoaffective disorder. Brain pathomorphology and abnormal basal growth hormone significantly predicted time to remission. CONCLUSIONS: These results indicate that the antipsychotic treatment response of first-episode schizophrenics is better than chronic multiepisode patients and suggest that specific pathobiologic markers reflect pathophysiologic processes that mediate antipsychotic treatment response.

Adult↗
PubMed1992

Normal eye tracking is associated with abnormal morphology of medial temporal lobe structures in schizophrenia.

Eye tracking and brain morphology assessed by magnetic resonance imaging were examined in 48 patients in their first episode of schizophrenia and in 15 normal controls. Schizophrenic patients showed higher rates of eye tracking dysfunction and more abnormal brain morphology involving the lateral ventricles, medial temporal lobe (MTL) structures and the frontal-parietal cortex than controls. Enlargement of the lateral ventricles and global rating of abnormal brain morphology were significantly more prevalent in male schizophrenics than female schizophrenics. These findings indicate that abnormalities in a variety of brain regions are present in some schizophrenics during the period shortly after the first hospitalization and could not be a function of treatment or chronic illness. We found no relation between abnormal eye tracking and any single feature of abnormal brain morphology. However, normal eye tracking was significantly associated with MTL abnormalities in schizophrenics, reflecting an inverse association between quality of eye tracking and degree of abnormality in MTL structures. These results suggest that abnormal eye tracking is not mediated by the same processes that lead to structural brain anomalies in schizophrenia.

Adolescent↗
PubMed1990

Behavioral response to methylphenidate and treatment outcome in first episode schizophrenia.

In order to examine the relationship of behavioral response to psychostimulants and acute treatment response, we administered methylphenidate (0.5 mg/kg i.v.), an indirect dopamine (DA) agonist, to 38 patients who met Research Diagnostic Criteria (RDC) for definite or probable schizophrenia or schizoaffective disorder, were experiencing their first acute episode of psychosis, and had received less than 12 weeks or no prior lifetime neuroleptic exposure. Following baseline methylphenidate infusions, patients received a standardized regimen of acute neuroleptic treatment. Methylphenidate produced an increase in psychopathology reflected by a worsening of both positive and negative symptoms. Using a priori criteria, 61 percent of patients exhibited psychotic symptom activation, and 39 percent showed no change. Activation during methylphenidate infusion during the initial acute phase of illness was not correlated with time to achieve antipsychotic treatment response but was associated with side-effect vulnerability.

Adolescent↗