Browsing by keyword "Central Nervous System Diseases"
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Developing an Adeno-Associated Viral Vector (AAV) Toolbox for CNS Gene Therapy: A DissertationNeurological disorders – disorders of the brain, spine and associated nerves – are a leading contributor to global disease burden with a sizable economic cost. Adeno-associated viral (AAV) vectors have emerged as an effective platform for CNS gene therapy and have shown early promise in clinical trials. These trials involve direct infusion into brain parenchyma, an approach that may be suboptimal for treatment of neurodegenerative disorders, which often involve more than a single structure in the CNS. However, overall neuronal transduction efficiency of vectors derived from naturally occurring AAV capsids after systemic administration is relatively low. We have developed novel capsids AAV-AS and AAV-B1 that lead to widespread gene delivery throughout the brain and spinal cord, particularly to neuronal populations. Both transduce the adult mouse brain >10-fold more efficiently than the clinical gold standard AAV9 upon intravascular infusion, with gene transfer to multiple neuronal sub-populations. These vectors are also capable of neuronal transduction in a normal cat. We have demonstrated the efficacy of AAV-AS in the context of Huntington's disease by knocking down huntingtin mRNA 33-50% after a single intravenous injection, which is better than what can be achieved by AAV9 at the particular dose. AAVB1 additionally transduces muscle, beta cells, pulmonary alveoli and retinal vasculature at high efficiency, and has reduced sensitivity to neutralizing antibodies in human sera. Generation of this vector toolbox represents a major step towards gaining genetic access to the entire CNS, and provides a platform to develop new gene therapies for neurodegenerative disorders.
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Use of meperidine in patient-controlled analgesia and the development of a normeperidine toxic reactionHYPOTHESIS: Intravenous patient-controlled analgesia (IV PCA) meperidine hydrochloride can be used with a reasonable margin of safety. DESIGN: A retrospective review was performed of 355 medical records of patients receiving IV PCA meperidine treatment. Four groups of patients were defined, based on daily meperidine dose and the presence or absence of central nervous system excitation adverse effects. Use of more than 600 mg/d of meperidine hydrochloride was considered a high dose. SETTING: University tertiary care hospital. PARTICIPANTS: Postoperative patients from general, orthopedic, neurosurgical, gynecological, and urologic procedures receiving IV PCA. INTERVENTIONS: If patients were judged to have consumed significant amounts of meperidine, the analgesic regimen was modified to (1) discontinue meperidine therapy, (2) substitute hydromorphone hydrochloride, or (3) decrease the use of meperidine by adding oral methadone hydrochloride or transdermal fentanyl citrate to the regimen. MAIN OUTCOME MEASURES: Patients who received less than 10 mg/kg per day of IV PCA meperidine hydrochloride therapy were unlikely to experience central nervous system excitatory adverse effects and maintain adequate analgesia. RESULTS: The mean meperidine hydrochloride consumption for those patients classified as high dose, asymptomatic was 13.3 mg/kg per day (95% confidence interval, 12.1-14.4 mg/kg per day). This differed statistically significantly (P<.05) from the mean meperidine hydrochloride dose in patients classified as high dose, symptomatic, which was 16.9 mg/kg per day (95% confidence interval, 14.7-19.2 mg/kg per day). The duration of meperidine use did not differ among the 4 patient groups. The incidence of a central nervous system toxic reaction associated with IV PCA meperidine therapy was 2%. CONCLUSIONS: We recommend 10 mg/kg per day as a maximum safe meperidine hydrochloride dose by an IV PCA device for no longer than 3 days. Daily patient evaluation is mandatory. Care must also be taken when using this dose to ensure the absence of renal dysfunction or enhanced hepatic metabolism of meperidine.
