Publications by authors named "Marion Schwartz"

11 Publications

  • Page 1 of 1

Newborn Screening System Performance Evaluation Assessment Scheme (PEAS).

Semin Perinatol 2010 Apr;34(2):105-20

National Newborn Screening and Genetics Center, Austin, TX 78759, USA.

Newborn screening (NBS) reaches approximately all of the 4 million newborns in the United States each year and has been effective in significantly reducing the morbidity and mortality that results from certain congenital conditions. The comprehensive NBS system can be divided into preanalytic (education and screening), analytic (laboratory testing), and postanalytic (reporting, short-term follow-up/tracking, diagnosis, treatment/management, ancillary services, and outcome evaluation) activities. To monitor and improve the screening system, there has been increasing emphasis on evaluation models. Federal sponsorship of a model performance evaluation and assessment scheme (PEAS) has resulted in a comprehensive listing of quality indicators for system self-assessment. We review the PEAS evolution process in an effort to illustrate the necessary infrastructure considerations in a well-functioning NBS system. Readers are encouraged to identify their role in the system and to interact appropriately at the local level. The comprehensive PEAS indicator list is provided as an Appendix.
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April 2010

Demography of Verreaux's sifaka in a stochastic rainfall environment.

Oecologia 2009 Sep 16;161(3):491-504. Epub 2009 Jun 16.

Department of Anthropology, Boston University, Boston, MA 02215, USA.

In this study, we use deterministic and stochastic models to analyze the demography of Verreaux's sifaka (Propithecus verreauxi verreauxi) in a fluctuating rainfall environment. The model is based on 16 years of data from Beza Mahafaly Special Reserve, southwest Madagascar. The parameters in the stage-classified life cycle were estimated using mark-recapture methods. Statistical models were evaluated using information-theoretic techniques and multi-model inference. The highest ranking model is time-invariant, but the averaged model includes rainfall-dependence of survival and breeding. We used a time-series model of rainfall to construct a stochastic demographic model. The time-invariant model and the stochastic model give a population growth rate of about 0.98. Bootstrap confidence intervals on the growth rates, both deterministic and stochastic, include 1. Growth rates are most elastic to changes in adult survival. Many demographic statistics show a nonlinear response to annual rainfall but are depressed when annual rainfall is low, or the variance in annual rainfall is high. Perturbation analyses from both the time-invariant and stochastic models indicate that recruitment and survival of older females are key determinants of population growth rate.
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September 2009

Medication status affects the relationship of symptoms to prepulse inhibition of acoustic startle in schizophrenia.

Psychiatry Res 2006 Dec 27;145(2-3):137-45. Epub 2006 Oct 27.

Atlanta Veterans Administration Medical Center, Decatur, GA, USA.

Inhibition of the acoustic startle response by a smaller preliminary nonstartling stimulus is termed prepulse inhibition (PPI). Schizophrenia patients have impairments in PPI that may not fully normalize even when they are clinically stable on medication, particularly typical antipsychotics. There is evidence that more severe symptoms are associated with more severe PPI abnormalities, but the effect of antipsychotics on this relationship is not clear. Seventy-three male schizophrenia patients underwent acoustic startle and PPI testing. Symptom ratings were performed using the Brief Psychiatric Rating Scale (BPRS) and its subscales. Fifty-two subjects were treated with antipsychotic medication at time of testing; 21 were unmedicated. For all subjects, PPI was negatively correlated with the BPRS psychological discomfort subscale but not with BPRS total symptoms, BPRS positive symptoms or BPRS negative symptoms. For medicated subjects analyzed separately, there were no correlations with BPRS total scores or any subscales. For the unmedicated subjects analyzed separately, there were significant correlations of lower PPI with greater severity of BPRS total symptoms, positive symptoms and the psychological discomfort subscale. These data indicate that more severe symptoms are associated with lower PPI, but that medication status is an important factor in the relationship between symptom severity and sensorimotor gating.
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December 2006

A placebo controlled, double-blind study of mecamylamine treatment for cocaine dependence in patients enrolled in an opiate replacement program.

Subst Abus 2005 Jun;26(2):5-14

New York University School of Medicine, New York, NY 10010, USA.

A placebo controlled, double-blind trial of mecamylamine treatment of cocaine dependence was performed in methadone or LAAM maintained subjects who met DSM-IV criteria for cocaine dependence. After an eight-week placebo run-in screening period, 35 subjects were randomly assigned to receive either mecamylamine (6 mg/day) or placebo transdermal patches for a 16-week treatment period. Outcome measures included quantitative urine benzoylecognine (BE) levels, self-report of cocaine use, cocaine craving, global impression scores, mood, retention, and safety. Mecamylamine was well tolerated, and study retention did not differ by treatment group. Evidence for cocaine use, based on urine BE levels and cocaine abstinence rates, did not differ by treatment group. Self reported cocaine use, cocaine craving, and global impression scores showed moderate improvement in both groups, with a significantly greater reduction in cocaine craving (p < 0.05) and self-rated severity of cocaine dependence (p < 0.05) in the placebo group. This pilot study does not support the effectiveness of mecamylamine for the treatment of cocaine dependence in methadone or LAAM maintained patients.
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June 2005

Effects of lower-cost incentives on stimulant abstinence in methadone maintenance treatment: a National Drug Abuse Treatment Clinical Trials Network study.

Arch Gen Psychiatry 2006 Feb;63(2):201-8

Mid Atlantic Node, The Johns Hopkins University School of Medicine, Baltimore, MD, USA.

Background: Contingency management interventions that provide tangible incentives based on objective indicators of drug abstinence have improved treatment outcomes of substance abusers, but have not been widely implemented in community drug abuse treatment settings.

Objective: To compare outcomes achieved when a lower-cost prize-based contingency management treatment is added to usual care in community methadone hydrochloride maintenance treatment settings.

Design: Random assignment to usual care with (n = 198) or without (n = 190) abstinence incentives during a 12-week trial.

Setting: Six community-based methadone maintenance drug abuse treatment clinics in locations across the United States.

Participants: Three hundred eighty-eight stimulant-abusing patients enrolled in methadone maintenance programs for at least 1 month and no more than 3 years.

Intervention: Participants submitting stimulant- and alcohol-negative samples earned draws for a chance to win prizes; the number of draws earned increased with continuous abstinence time.

Main Outcome Measures: Total number of stimulant- and alcohol-negative samples provided, percentage of stimulant- and alcohol-negative samples provided, longest duration of abstinence, retention, and counseling attendance.

Results: Submission of stimulant- and alcohol-negative samples was twice as likely for incentive as for usual care group participants (odds ratio, 1.98; 95% confidence interval, 1.42-2.77). Achieving 4 or more, 8 or more, and 12 weeks of continuous abstinence was approximately 3, 9, and 11 times more likely, respectively, for incentive vs usual care participants. Groups did not differ on study retention or counseling attendance. The average cost of prizes was 120 dollars per participant.

Conclusion: An abstinence incentive approach that paid 120 dollars in prizes per participant effectively increased stimulant abstinence in community-based methadone maintenance treatment clinics.
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February 2006

A placebo-controlled screening trial of celecoxib for the treatment of cocaine dependence.

Addiction 2005 Mar;100 Suppl 1:32-42

Department of Psychiatry, New York University School of Medicine, VA New York Harbor Healthcare System, New York, NY 10010, USA.

Aims: To conduct a medication screening trial study on the efficacy of celecoxib versus placebo for the treatment of cocaine dependence.

Design: A modified blinded, parallel group study in an outpatient setting using the Cocaine Rapid Efficacy and Safety Trials (CREST) study design.

Setting: The study was performed at the New York Medications Development Research Unit (MDRU).

Participants: All participants met Diagnostic and Statistical Manual version IV (DSM-IV) criteria for cocaine dependence and provided at least two urine samples positive for benzoylecgonine (BE) during the 2-week screening period. Twenty-three participants were enrolled in the treatment phase of the study.

Intervention: After a 2-week screening period, subjects were assigned randomly to receive either celebrex (200 mg/day) or placebo for an 8-week treatment period. All subjects also received individual cognitive behavioral counseling during treatment.

Measurements: Primary outcome measures included quantitative urine benzoylecgonine (BE) levels, self-report of drug use and global impression scores. Secondary outcomes included cocaine craving, study retention and related psychosocial measures. Safety measures included adverse event monitoring, vital signs and extrapyramidal side-effects tests.

Results: Study retention was similar across both treatment groups and safety measures indicated that celecoxib was moderately tolerated. Cocaine use, as measured by self-report and urine BE levels at end of treatment, indicated weaker improvement in the celecoxib group. Reductions in the intensity of cocaine craving were also weaker in the celecoxib group. Cocaine abstinence rates, global impression scores and all other related psychometric measures did not differ significantly between treatment groups.

Conclusion: This study does not support the effectiveness of celecoxib for the treatment of cocaine dependence.
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March 2005

Effects of D-cycloserine on negative symptoms in schizophrenia.

Schizophr Res 2004 Dec;71(2-3):239-48

Atlanta Veterans Affairs Medical Center/Emory University School of Medicine, Atlanta, GA 30033, USA.

Introduction: The negative and cognitive symptoms of schizophrenia are poorly responsive to neuroleptic treatment. Glutamatergic dysfunction may mediate some of these symptoms. Low dose D-cycloserine (DCS) is a partial agonist at the glycine site of the NMDA-associated receptor complex, noncompetitively enhancing NMDA neurotransmission. Prior studies suggest a beneficial effect of DCS on negative symptoms and cognition. This treatment trial was initiated to confirm and extend these findings.

Methods: Twenty-two male schizophrenic subjects displaying prominent negative symptoms who were stabilized on typical neuroleptics completed the study. A randomized double-blind parallel group design was used to compare the effects of 50 mg p.o. QD of DCS to placebo over 4 weeks. The two subject groups did not differ significantly in age, age of onset of illness or time on current neuroleptic treatment. Symptoms were rated by means of the SANS, BPRS and Abrams and Taylor rating scale. Cognition was assessed with the Sternberg Memory Test and the Continuous Performance Test.

Results: Both medication groups improved over the 4 weeks of treatment. However, there were no significant differences between the DCS and placebo group on any symptom rating. DCS effects on cognition did not differ from placebo.

Discussion: This study did not detect improvement in negative symptoms or cognitive performance with DCS treatment that has been found in some prior studies. This negative finding may be attributed to small sample size, relatively short duration of treatment and the overall modest effect of DCS. Future studies of DCS should be adequately powered to detect a small to medium effect size and should provide for a longer treatment phase than was used in this study in order to avoid a type II error.
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December 2004

Menstrual cycle phase effects on prepulse inhibition of acoustic startle.

Psychophysiology 2004 May;41(3):401-6

Department of Psychiatry & Behavioral Sciences, Emory University School of Medicine, Atlanta, Georgia, USA.

Prepulse inhibition (PPI) represents an attenuation of the startle reflex following the presentation of a weak prepulse at brief intervals prior to the startle eliciting pulse. It has been shown that increases in striatal dopamine levels decrease PPI; because dopamine release is sensitive to estrogen, it is likely that PPI varies across the menstrual cycle. Cross-sectional studies looking at estrogen effects suggest that this may be true. In this study, we compare effects of menstrual phase on PPI in a between-group design (men, follicular phase women, and luteal phase women) as well as a within-subjects design (women across the two phases). The study found a between-group as well as a within-subjects effect of phase on PPI. PPI in follicular phase women did not differ significantly from PPI in men. However, PPI was reduced in luteal women compared to follicular women. These data provide evidence that ovarian hormones affect sensorimotor gating.
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May 2004

Parasitologic analyses of the sifaka (Propithecus verreauxi verreauxi) at Beza Mahafaly, Madagascar.

J Zoo Wildl Med 2003 Sep;34(3):274-7

Anthropological Parasitology Laboratory, Department of Anthropology, Yale University, 51 Hillhouse Avenue, New Haven, Connecticut 06520, USA.

A cross-sectional parasitologic survey of a population of wild sifaka (Propithecus verreauxi verreauxi) was conducted at the Beza Mahafaly Special Reserve in southwest Madagascar. Ninety fecal samples were collected from thirty 1- to 30-yr-old male and female sifakas, and the formalin-preserved and polyvinyl alcohol-preserved specimens were examined using the zinc sulfate flotation and formalin-ethyl acetate sedimentation techniques. No intestinal parasites were recovered, possibly because the sifakas are arboreal in a dry, riverine habitat and lack human contact. Low rates of parasitic infection may have contributed to the evolution of later age at first reproduction and longer reproductive lifespan, for body mass, in Propithecus compared with other placental mammals.
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September 2003

Prepulse inhibition of acoustic startle in subjects with schizophrenia treated with olanzapine or haloperidol.

Psychiatry Res 2003 Aug;120(1):1-12

Emory University School of Medicine, GA, Atlanta, USA.

Studies of the acoustic startle response and of its inhibition by the presentation of a non-startling preliminary stimulus (prepulse inhibition, PPI) have revealed deficits in PPI in schizophrenic subjects compared to healthy controls. Animal studies indicate that atypical antipsychotics improve PPI deficits induced by NMDA antagonists more consistently than typical antipsychotics. The effect of medication status on PPI in schizophrenia is unresolved in the literature. In the current study the effects on PPI of the atypical antipsychotic olanzapine and the typical antipsychotic haloperidol were compared to the unmedicated state in subjects with schizophrenia. In a between-group design, 11 schizophrenic subjects on olanzapine, 16 subjects on haloperidol, and 14 subjects who were on no medication received acoustic startle testing with PPI determination. ANOVAs revealed no significant differences in startle to pulse alone stimuli, habituation of startle, or PPI between the olanzapine, haloperidol and unmedicated groups. These 41 subjects with schizophrenia were compared to a group of 21 historical healthy controls and found to have reduced PPI. These data do not indicate a preferential effect of olanzapine compared to haloperidol on sensorimotor gating in schizophrenia. The results are consistent with the hypothesis that PPI impairments are relatively stable across treatment conditions.
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August 2003

Effect of treatment status on prepulse inhibition of acoustic startle in schizophrenia.

Psychopharmacology (Berl) 2003 Apr 11;167(1):63-71. Epub 2003 Mar 11.

Mental Health Service/116A, Atlanta Veterans Affairs Medical Center, 1670 Clairmont Road, Decatur, GA 30033, USA.

Rationale: The acoustic startle response is inhibited when the startling stimulus is preceded by a weaker non-startling acoustic stimulus. This phenomenon, termed prepulse inhibition of acoustic startle (PPI), is impaired in schizophrenics compared to normal controls. To date, there is conflicting evidence regarding whether PPI impairments improve with antipsychotic treatment.

Objectives: To examine the effect of medication status on PPI in schizophrenic subjects.

Methods: First, we performed acoustic startle testing on 16 schizophrenic subjects when they were acutely decompensated off medication and later after they were stabilized on antipsychotic treatment. Second, in a between-group design, we tested 21 schizophrenic subjects off medication, 16 subjects on atypical neuroleptics, and 27 subjects on typical neuroleptics.

Results: In both the test-retest study and the between-group study, ANOVAs revealed no significant changes in startle to pulse alone stimuli, habituation of startle to pulse alone stimuli, PPI, latency to response onset, or latency to response peak between the treatment conditions.

Conclusions: Our results do not support the hypothesis that impaired sensorimotor gating in schizophrenia improves with antipsychotic treatment. Rather, impaired gating persists despite symptomatic improvement on medication.
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April 2003