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For most youth with autism spectrum disorders (ASD), employment upon graduation from high school or college is elusive. Employment rates are reported in many studies to be very low despite many years of intensive special education services. This paper presented the preliminary results of a randomized clinical trial of Project SEARCH plus ASD Supports on the employment outcomes for youth with ASD between the ages of 18-21 years of age. This model provides very promising results in that the employment outcomes for youth in the treatment group were much higher in non-traditional jobs with higher than minimum wage incomes than for youth in the control condition. Specifically, 21 out of 24 (87.5 %) treatment group participants acquired employment while 1 of 16 (6.25 %) of control group participants acquired employment.

Background: A new benzodiazepine derivative, CNS 7056, has been developed to permit a superior sedative profile to current agents, i.e., more predictable fast onset, short duration of sedative action, and rapid recovery profile. This goal has been achieved by rendering the compound susceptible to metabolism via esterases. The authors now report on the profile of CNS 7056 in vitro and in vivo. Methods: The affinity of CNS 7056 and its carboxylic acid metabolite, CNS 7054, for benzodiazepine receptors and their selectivity profiles were evaluated using radioligand binding. The activity of CNS 7056 and midazolam at subtypes (α1β2γ2, α2β2γ2, α3β2γ2, α5β2γ2) of the γ-aminobutyric acid type A (GABAA) receptor was evaluated using the whole cell patch clamp technique. The activity of CNS 7056 at brain benzodiazepine receptors in vivo was measured in rats using extracellular electrophysiology in the substantia nigra pars reticulata. The sedative profile was measured in rodents using the loss of righting reflex test. Results: CNS 7056 bound to brain benzodiazepine sites with high affinity. The carboxylic acid metabolite, CNS 7054, showed around 300 times lower affinity. CNS 7056 and CNS 7054 (10 μm) showed no affinity for a range of other receptors. CNS 7056 enhanced GABA currents in cells stably transfected with subtypes of the GABAA receptor. CNS 7056, like midazolam and other classic benzodiazepines, did not show clear selectivity between subtypes of the GABAA receptor. CNS 7056 (intravenous) caused a dose-dependent inhibition of substantia nigra pars reticulata neuronal firing and recovery to baseline firing rates was reached rapidly. CNS 7056 (intravenous) induced loss of the righting reflex in rodents. The duration of loss of righting reflex was short (< 10 min) and was inhibited by pretreatment with flumazenil. Conclusions: CNS 7065 is a high-affinity and selective ligand for the benzodiazepine site on the GABAA receptor. CNS 7056 does not show selectivity between GABAA receptor subtypes. CNS 7056 is a potent sedative in rodents with a short duration of action. Inhibition of substantia nigra pars reticulata firing and the inhibition of the effects of CNS 7056 by flumazenil show that it acts at the brain benzodiazepine receptor.

The aim of these studies was to establish a rapid in vivo assay for evaluating potential "cocaine antagonists," i.e., drugs postulated to block cocaine binding to the dopamine transporter (DAT) without corresponding blockade of dopamine reuptake. The assay is based on the ability of dopamine, and drugs that elevate synaptic dopamine levels, to inhibit the extracellular single unit activities of midbrain dopamine neurons in chloral hydrate-anesthetized rats. As expected, cocaine itself (0.06-16 mg/kg, i.v.) caused a dose-dependent inhibition of firing of both substantia nigra and ventral tegmental area (VTA) dopamine neurons, but had a significantly higher potency on VTA than nigral dopamine cells (ED(50)'s 1.2 and 8.8 mg/kg, respectively). VTA cells were also inhibited to a greater extent (to 4.7 +/- 4.5% vs. 41.3 +/- 6.3% of baseline rates at 16 mg/kg, respectively). We next evaluated GBR12909, a piperazine analog promoted as a "cocaine antagonist" because of its ability to bind with high affinity to the DAT, while only modestly elevating extracellular dopamine levels. The agonist- and antagonist-like properties of GBR12909 were evaluated on only VTA dopamine cells since these neurons were more fully inhibited by cocaine and have been implicated in its rewarding effects. Given alone, GBR12909 exhibited modest "cocaine-like" activity insofar as it partially inhibited VTA dopamine neurons (to 59.0 +/- 4.6% of baseline at 8 mg/kg). However, consistent with an antagonist profile, pretreatment with a low (0.5 mg/kg) dose of GBR12909, which depressed firing only slightly, resulted in a >2-fold rightward shift in the dose-response curve to cocaine (ED(50) 2.6 mg/kg). We conclude that electrophysiological testing of putative "anti-cocaine" drugs for their abilities to inhibit the firing of VTA dopamine neurons, and to block their inhibitory responses to cocaine, may provide a rapid in vivo screen for compounds expected to behave as functional cocaine antagonists in the dopamine reward system.

Top of pageAbstract Type A Niemann-Pick disease (NPA) is a fatal neurometabolic childhood disorder caused by a genetic deficiency of acid sphingomyelinase (ASM). The lack of functional ASM results in sphingomyelin and cholesterol accumulation within the lysosomal compartment of cells throughout the brain, leading to neurodegeneration. In this study, we investigated the efficacy of using AAV gene therapy as a form of ASM enzyme replacement to correct lysosomal pathology and to prevent Purkinje cell death in a mouse ASM knockout (ASMKO) model of NPA. An AAV serotype-2 vector encoding human ASM under the control of CMV promoter (AAV2-CMV-ASM) was injected into the adult hippocampus of one hemisphere. This resulted in human ASM mRNA and protein expression in all major cell layers of the ipsilateral hippocampus for up to 15 weeks post-injection. Transduced cells were also present in the entorhinal cortex, medial septum, supramammillary nucleus, and contralateral hippocampus in a pattern consistent with retrograde transport of AAV2. There was a substantial reduction of distended lysosomal pathology and an almost complete reversal of cholesterol accumulation in all brain regions expressing human ASM. Following injection of AAV2-CMV-ASM into other brain regions (e.g. striatal and cerebellar circuits), we observed a similar pattern of local and distant (retrograde) transduction and reversal of pathology. Within the cerebellum of ASMKO mice, there is an almost complete loss of Purkinje cells between 7 and 20 weeks of age. AAV2-CMV-ASM was injected into the ASMKO cerebellum between 5 and 7 weeks, and treated mice were sacrificed 15 weeks later (20–22 weeks old). These injections resulted in neuroprotection as evidenced by the preservation of large numbers of human ASM mRNA- and protein-positive Purkinje cells within treated lobules. We also found that intraventricular injection of juvenile (3 week old) ASMKO mice resulted in Purkinje cell transduction, human ASM expression and survival for up to 18 weeks post-injection. These results demonstrate that viral vector delivery via the cerebrospinal fluid is an effective way to target Purkinje cells for genetic manipulation. We are currently investigating different promoters and AAV serotypes for vector optimization. To this end, we have generated an AAV serotype-1 vector encoding human ASM under the control of chicken beta-actin promoter (AAV1-CBA-ASM). Administration into the cerebrum resulted in long-term human ASM expression and widespread clearance of cholesterol deposits for up to 26 weeks. Preliminary results have also shown that injection of AAV1-CBA-ASM into the cerebellum of young ASMKO mice preserved rotorod performance, a test sensitive to proprioceptive deficits caused, in part, by Purkinje cell degeneration. In conclusion, our data show that AAV-mediated human ASM enzyme replacement therapy leads to long-lasting, widespread reversal of lysosomal storage pathology, neuroprotection and functional sparing in the ASMKO mouse model of NPA.