Use of psychoactive substances in persons with spinal cord injury: a literature review.

OBJECTIVE: To undertake a critical review of literature on use of legal and illegal psychoactive substances (PAS) in persons with spinal cord injury (SCI) before and after trauma. MATERIAL AND METHODS: Hundred and five articles published between 1980 and 2014 on alcohol and drug use in persons with SCI before and after trauma were retrieved from the PubMed and PsycInfo search engines. RESULTS: Before injury, 25% to 96% of people with SCI reported using alcohol, while 32% to 35% had used illegal drugs. At the time of injury, 31% to 50% of individuals with SCI were intoxicated with alcohol, 16% to 33% with drugs and 26% with a combination of drugs and alcohol. Among those reporting PAS use before injury, up to 50% stated that they had reduced their use during active rehabilitation, during which time only 6% consumed psychoactive substances for the first time. A variety of risk factors are associated with consumption subsequent to spinal cord injury: personality alteration (impulsiveness, aggressiveness), posttraumatic depression, poor coping skills, lack of social support and pain. PAS use can affect the process of rehabilitation, diminish the effectiveness of medication and result in various medical complications. DISCUSSION/CONCLUSIONS: Few studies have explored the use of alcohol, drugs and psychoactive medications before SCI and during active rehabilitation. To our knowledge, no study has analyzed the evolution of PAS use after hospital discharge, even though return home is associated with new stressors that may trigger risky behaviors. It should be a priority, as early as possible during rehabilitation, to detect persons at risk of developing PAS abuse.

Sci-Fri AM: YIS-02: Evaluation of the LabPET4 imaging capabilities for in vivo small animal imaging.

Positron Emission Tomography (PET) is a non-invasive technique to visualize metabolic and physiological processes in vivo. Excellent imaging capabilities such as spatial resolution and count rate performance are essential to achieve accurate information about the observed processes. It is for this purpose that the LabPET scanner, an avalanche photodiode (APD)-based fully digital scanner PET scanner, was initially developed. Two variants of the scanner exist: LabPET4 and LabPET8 with 3.75 and 7.5 cm axial lengths respectively. The range of the transaxial FOV is up to 10 cm therefore it can easily accommodate mice and rats. The aim of this work is to evaluate LabPET4 imaging in several phantoms and small animals. Spatial resolution was determined using a point source and hot spots phantoms. The latter were used to assess recovery coefficients (RC) obtained by taking the ratio of hot spot maximum values compared to the biggest spot maximum value. FBP reconstructed tangential/radial resolution is 1.3/1.4 mm FWHM (2.5/2.4 FWTM) at the field of view center. With an Ultra Micro Hot Spot Phantom, 1 mm spots are clearly resolved. Count rate performance was obtained for mouse-size and rat-size phantoms. For mouse phantom, scatter fraction is 18%, noise equivalent count rate (NEC) peak is 120 kcps at 5.6 mCi and true coincidences peak is 215 kcps at 6.6 mCi. Mice and rats were imaged with Na18F and 18FDG. LabPET4 imaging capabilities achieve state-of-the-art requirements for molecular imaging and therefore can provide excellent quality images.

Sci-Sat AM(1): Imaging-08: Small animal APD PET detector with submillimetric resolution for molecular imaging.

Visualization and quantification of biological processes in mice, the preferred animal model in most preclinical studies, require the best possible spatial resolution in positron emission tomography (PET). A new 64-channel avalanche photodiode (APD) detector module was developed to achieve submillimeter spatial resolution for this purpose. The module consists of dual 4 × 8 APD arrays mounted in a custom ceramic holder. Individual APD pixels having an active area of 1.1 × 1.1 mm2 at a 1.2 mm pitch can be fitted to an 8 × 8 LYSO scintillator block designed to accommodate one-to-one coupling. An analog test board with four 16-channel preamplifier ASICs was designed to be interfaced with the existing LabPET digital processing electronics. At a standard APD operating bias, a mean energy resolution of 27.5 ± 0.6% was typically obtained at 511 keV with a relative standard deviation of 13.8% in signal amplitude for the 64 individual pixels. Crosstalk between pixels was found to be well below the typical lower energy threshold used for PET imaging applications. With two modules in coincidence, a global timing resolution of 5.0 ns FWHM was measured. Finally, an intrinsic spatial resolution of 0.8 mm FWHM was measured by sweeping a 22Na point source between two detector arrays. The proposed detector module demonstrates promising characteristics for dedicated mouse PET imaging at submillimiter resolution.

Expression of FHIT in primary cultures of human epithelial ovarian tumors and malignant ovarian ascites.

Abnormal FHIT gene expression has been reported in a variety of epithelial tumors shown to harbor deletions of chromosome 3p14, the chromosomal assignment of this gene. Recently, we described loss of heterozygosity of 3p in a subset of epithelial ovarian cancers. To investigate a potential role of the FHIT gene in ovarian cancer, we examined primary cell cultures derived from normal ovarian surface epithelium, ovarian tumors, and the cellular fraction of malignant ascites to determine the expression of FHIT by using reverse transcription-polymerase chain reaction. Included in this analysis were four spontaneously immortalized cell lines: three derived from malignant epithelial ovarian tumors (TOV21G, TOV112D, and TOV81D) and one from malignant ovarian ascites (OV90). OV90 was previously shown to harbor a deletion of the whole p arm of chromosome 3. The FHIT transcript was not detectable in two of 11 primary cultures derived from normal ovarian surface epithelium or in a primary culture derived from malignant ovarian ascites, whereas the remaining samples (34 malignant, eight borderline, and three benign specimens), exhibited identical expression patterns. In each case, this pattern was consistent with the co-expression of a normal FHIT transcript and a smaller transcript. DNA sequencing revealed that the abnormal-sized message lacked exons 4-7 (inclusive), which were deleted at their exact intron-exon splice sites. The aberrant-sized transcript was detectable by Northern blot analysis. There was no concordance between FHIT expression and loss of heterozygosity at the FHIT locus. Northern blot analysis also revealed that FHIT was differentially expressed, and the spontaneously immortalized cell lines TOV21G and TOV112D showed the highest level of expression. Because the same reverse transcription-polymerase chain reaction expression pattern was observed in both normal and tumor-derived primary cell cultures, these results argue against a significant role for FHIT in epithelial ovarian tumorigenesis.

Manganese and other trace elements in urban snow near an expressway.

The Mn contamination arising from the combustion of MMT (methylcyclopentadienyl manganese tricarbonyl) in unleaded gasoline was assessed using snow collected at different distances 15, 25, 125 and 150 m from an expressway (Montreal, Canada) in February 1993. The snow samples were analyzed by atomic absorption and by neutron activation for total Mn, Mg, Cu, V, Al, Zn, Fe, Na, and Ca concentrations in the soluble (<0.4 microm) and particulate fractions. ANOVA with ranked values was performed to compare element concentrations and soluble/particulate ratios among receptor sites and depths. Principal component analysis was used to describe the spatiotemporal variations of the deposition rates and the influence of meteorological factors. The average concentration of all trace elements, except Mg, Cu, and V, decreased significantly (p<0.05) from receptor sites near the road (15-25 m) to those farther away (125-150 m). The deposition rates of all metals and ions, except Cu, were highly positively correlated (tau = 0.5-0.9) with each other and inversely correlated with snowfalls. Wind frequency showed no correlation with deposition rate. The spatial trend was similar for all these elements making it difficult to distinguish Mn arising from the combustion of MMT from that due to other sources, such as road dust. Only the soluble/particulate ratio calculated for Mn seemed higher than that for the other metals, which might be explained by the particle size of Mn from MMT (0.2-0.4 microm). The present study only indicates a direct contamination of the snow by road activities and substantial deposition of trace elements near the roadway; no clear link can be established between motor vehicle emissions and the concentration of Mn in snow.