Desorption electrospray ionization-mass spectrometric analysis of low vapor pressure chemical particulates collected from a surface.

The collection of a low vapor pressure chemical simulant triethyl phosphate sorbed onto silica gel (TEP/SG) from a surface with subsequent analysis of the TEP/SG particulates using desorption electrospray ionization-mass spectrometry (DESI-MS) is described. Collection of TEP/SG particulates on a surface was accomplished using a sticky screen sampler composed of a stainless steel screen coated with partially polymerized polydimethylsiloxane (PDMS). DESI-MS analysis of TEP/SG particulates containing different percentages of TEP sorbed onto silica gel enabled the generation of response curves for the TEP ions m/z 155 and m/z 127. Using the response curves the calculation of the mass of TEP in a 25 wt% sample of TEP/SG was calculated, results show that the calculated mass of TEP was 14% different from the actual mass of TEP in the sample using the m/z 127 TEP ion response curve. Detection limits for the TEP vapor and TEP/SG particulates were calculated to be 4 µg and 6 particles, respectively.

The effect of nucleotomy on facet joint loading - a porcine in vitro study.

BACKGROUND: Lumbar facet joints have been cited as a possible origin of low-back pain. A relationship between disc height decrease and facet joint degeneration has been reported. Facet joint degeneration may also be triggered by nucleotomy, performed on prolapsed discs, which might change the natural load sharing between the anterior and posterior structures of the spine. In this study load bearing of the facet joints was compared between natural and nucleotomised spinal segments. METHODS: Nine porcine lumbar motion segments were tested quasi-statically in ±1.5° extension-flexion under 700 N constant compression loading. The kinematics of the spinal segments were recorded as a response to the applied load. These kinematics were subsequently applied to the segments with the ligaments and disc sequentially removed and the reaction forces measured. This was performed in samples with and without nucleotomy. Comparison of the reaction forces allowed a direct comparison between healthy and pathological force transmission over the facet joints. Load sharing was related to the proportion of removed nucleus. FINDINGS: The proportion of applied compression force supported by the facets increased from a mean of 40.7% (standard deviation, SD 10.0%) to 82.0% (SD 7.2%) after nucleotomy averaged over the entire extension-flexion regime. No correlation was observed between facet loading and the proportion of the nucleus removed. INTERPRETATION: Increased facet loading after nucleotomy might cause greater cartilage wear, which may be related to facet joint degeneration. The independence of facet loading on the proportion of nucleus removed might be due to a complete pressure loss once the annulus is incised.

Sampler for collection and analysis of low vapor pressure chemical (LVPC) particulates/aerosols.

Detection of low vapor pressure chemicals (LVPCs) such as pesticides and other toxic/hazardous materials on various environmental surfaces as well as LVPC aerosols is a significant challenge for current vapor phase detectors. We describe a novel sampling device which utilizes stainless steel screens coated with a sticky polydimethylsiloxane coating for collecting LVPCs aerosolized off of a surface. Results are presented for the collection and detection of a pesticide simulant, dimethyl methylphosphonate sorbed onto silica gel (DMMP/SG), using direct analysis in real time-cylindrical ion trap mass spectrometry (DART-CITMS).

Collection method for chemical particulates on surfaces with detection using thermal desorption-ion trap mass spectrometry.

Successful analysis of particulate/low vapor pressure analytes such as explosives and toxic chemicals, and commercial pesticides require new sampling tools that enable detection of these analytes using current vapor phase detection instruments. We describe a sampling approach that uses stainless steel screens coated with a sticky polydimethyl siloxane (PDMS) coating to capture particulates from surfaces. Preliminary results for the collection of dimethyl methylphosphonate (DMMP) sorbed onto silica gel (SG) particulates (DMMP/SG) from a surface with subsequent analysis by thermal desorption-cylindrical ion trap mass spectrometry (TD-CITMS) are reported.

A brief treatment engagement intervention for individuals with co-occurring mental illness and substance use disorders: results of a randomized clinical trial.

Study objectives were to evaluate a brief intervention designed to facilitate outpatient engagement following an inpatient psychiatric stay for individuals with mental illness and substance use. A total of 102 veterans were randomly assigned to one of two conditions: (1) Time Limited Care-Coordination (TLC), an eight-week co-occurring disorders intervention or (2) a matched attention (MA) control condition in the form of health education sessions. Both groups also received treatment as usual in inpatient and outpatient settings. Sixty-nine percent of TLC participants attended an outpatient appointment within 14 days of discharge, compared to only 33% of MA participants (P < 0.01). TLC participants were also more likely to be engaged in outpatient services at the end of the intervention period (44 vs. 22%, P < 0.01). This study provided evidence that an eight-week intervention could improve treatment engagement. Research is currently underway to examine impact of TLC intervention beyond the 8 week study period.

A brief community linkage intervention for veterans with a persistent mental illness and a co-occurring substance abuse disorder

No disponible

Objective: Individuals with co-occurring psychiatric and substance abuse problems often exhibit poor outpatient treatment engagement and re-hospitalization following discharge from acute psychiatric services. Although case management can improve treatment engagement and reduce attrition, these services are often delivered indefinitely, limiting the availability of treatment slots. In an effort to reduce re-hospitalization rates and improve outcomes during the transition from inpatient to outpatient treatment, we developed and evaluated Time-Limited Case Management (TLC), an eight-week integrated mental health and substance abuse augmentation intervention. Method: Sixty-five dually diagnosed veterans admitted to inpatient psychiatric treatment were included in the program evaluation, 32 who received the TLC service in addition to Treatment as Usual (TAU) that began during inpatient treatment and continued after the transition to outpatient services, and a comparison group of 33 who received only TAU without transitional support provided through the TLC augmentation service. Results: The TLC group had fewer days and episodes of hospitalization at two and six month post-study entry. Furthermore, the TLC group exhibited greater improvements on the Global Assessment of Functioning from baseline to the six-month follow-up. Conclusion: TLC appears to be an effective transitional augmentation service with benefits that persist beyond the eight weeks of the program. Future research should include a larger and more rigorously controlled trial to confirm the efficacy and unique contributions of the intervention (AU)

The efficacy of olanzapine for decreasing cue-elicited craving in individuals with schizophrenia and cocaine dependence: a preliminary report.

OBJECTIVE: Although a growing body of research suggests that atypical neuroleptic medications are efficacious in the treatment of cocaine addiction among individuals with schizophrenia, more rigorously controlled trials are needed. To extend this research, we performed a 6-week double-blind study comparing olanzapine to haloperidol with the primary objective of reducing cue-elicited cocaine craving and the secondary aims of decreasing substance use, improving psychiatric symptoms, and determining an effect size for future studies. METHODS: Thirty-one subjects with cocaine dependence and schizophrenia were randomized to olanzapine or haloperidol, underwent a cue-exposure procedure, and completed psychiatric and substance abuse ratings. RESULTS: Individuals in the olanzapine group who completed the study had a significant reduction on the energy subscale of the Voris Cocaine Craving Scale at study completion compared with individuals in the haloperidol group. The olanzapine-treated group also had lower, but not statistically significant, PANSS General Psychopathology Subscale scores and fewer positive urine toxicology screens compared with those in the haloperidol group. CONCLUSION: This small, but rigorously controlled, pilot trial provides additional evidence for the use of atypical antipsychotics for the treatment of individuals with co-occurring schizophrenia and cocaine dependence. Reductions in craving were associated with medium to large effect sizes.

Schizophrenia with obsessive compulsive features.

While the obsessive compulsive (OC) phenomena in schizophrenia have been described over the years, the condition has received increasing attention in recent years. The clinical and biological significance of OC symptoms in schizophrenia, however, still remain controversial. Although OC symptoms in schizophrenia were once thought to occur rarely and were associated with more benign clinical courses, recent studies have shown greater prevalence rate and poor outcome. In addition, the OC subgroup of schizophrenia responds poorly to the traditional antipsychotic treatments, but may respond positively to adjunctive anti-OCD regimen according to the emerging clinical evidence.(1) While further systematic studies are needed to explore the clinical neurobiological implications of OC phenomena in patients with schizophrenia, current evidence suggests that these patients require specific symptom assessment and individualized pharmacological and psychotherapeutic treatment interventions for optimal outcome.

A double-blind placebo-controlled pilot study of risperidone for decreasing cue-elicited craving in recently withdrawn cocaine dependent patients.

Cocaine use causes an initial increase in dopamine and serotonin neurotransmission that is largely responsible for the pleasurable and reinforcing effects of the drug. Dysregulation of these neurotransmitters during withdrawal plays an important role in craving. Recent research has focused on the use of dopamine and serotonin antagonists early in recovery to reduce cocaine craving in both schizophrenic and non-schizophrenic cocaine dependent patients. This 2-week, double blind, placebo-controlled study compared risperidone vs. placebo in reducing cue-elicited cocaine craving. Thirty-four subjects with cocaine dependence were randomized to either risperidone or a placebo and underwent a weekly cue-exposure procedure. Although both groups had a reduction in craving over time, there were no significant differences among those treated with risperidone (n=19) compared to those taking a placebo (n=16) on the four craving dimensions. The results do not support the hypothesis that risperidone reduces cocaine craving among non-schizophrenic cocaine-dependent individuals.

Cognitive disparity in schizophrenics with and without cocaine dependency.

Although cognition has been investigated in individuals with schizophrenia and in non-schizophrenic cocaine abusers, few studies have focused on cocaine-abusing schizophrenics. Previous studies have shown contradictory results despite the fact that individuals with schizophrenia and cocaine dependence have worse long-term outcomes, and that each disorder separately is associated with neuropsychological impairment. The present study intended to clarify these inconsistencies with a comprehensive neuropsychological battery. Twenty-four cocaine-dependent schizophrenics and 23 non-drug abusing schizophrenics were recruited from the VA. Participants were administered tests focusing on motor skills, processing speed, attention, concentration, and executive functioning. While individuals with schizophrenia and cocaine dependence performed worse on the Grooved Peg Board and the Stroop A, the non-drug abusing schizophrenics performed worse on Trails Part A and B. However, a MANOVA failed to show group differences in overall neuropsychological performance. These findings are similar to the existing literature and suggest that cocaine may compromise motor functioning.