Recombinant viral vectors derived from adeno-associated virus serotype 2 (rAAV2) have been investigated as highly effective vehicles for gene transfer to the central nervous system (CNS). Transduction with rAAV2 vectors results in long-term transgene expression in CNS neurons. Optimal injection parameters leading to efficient targeting and spread of the transgene to large neuroanatomical regions are important in molecular gene therapy studies of the CNS. In the present study, we reexamined the effects of both local and systemic administration of mannitol-induced hyperosmolality on facilitation of transgene expression and vector distribution in the CNS. Systemic intraperitoneal administration of mannitol prior to vector administration improved gene transfer to striatal neurons, increasing the total number of transduced cells by 400% and vector distribution by 200%. On the other hand, local coadministration of mannitol in the striatum increased the number of transduced striatal neurons by 25% and had little effect on transduction volume. In conclusion, we have demonstrated that systemic coadministration of mannitol significantly enhances transgene spread of rAAV2 viral delivery in the brain to a much greater degree than local coadministration.

We present genetic evidence that an in vivo role of α-synuclein (α-syn) is to inhibit phospholipase D2 (PLD2), an enzyme that is believed to participate in vesicle trafficking, membrane signaling, and both endo- and exocytosis. Overexpression of PLD2 in rat substantia nigra pars compacta (SNc) caused severe neurodegeneration of dopamine (DA) neurons, loss of striatal DA, and an associated ipsilateral amphetamine-induced rotational asymmetry. Coexpression of human wild type α-syn suppressed PLD2 neurodegeneration, DA loss, and amphetamine-induced rotational asymmetry. However, an α-syn mutant defective for inhibition of PLD2 in vitro also failed to inhibit PLD toxicity in vivo. Further, reduction of PLD2 activity in SNc, either by siRNA knockdown of PLD2 or overexpression of α-syn, both produced an unusual contralateral amphetamine-induced rotational asymmetry, opposite to that seen with overexpression of PLD2, suggesting that PLD2 and α-syn were both involved in DA release or reuptake. Finally, α-syn coimmunoprecipitated with PLD2 from extracts prepared from striatal tissues. Taken together, our data demonstrate that α-syn is an inhibitor of PLD2 in vivo, and confirm earlier reports that α-syn inhibits PLD2 in vitro. Our data also demonstrate that it is possible to use viral-mediated gene transfer to study gene interactions in vivo.

Importance: Histoplasmosis, a systemic mycosis caused by the fungus Histoplasma capsulatum, primarily affects immune-suppressed patients and commonly involves the lung and rarely the central nervous system (CNS). Herein, we report a case of isolated CNS histoplasmosis presenting with pontine stroke and meningitis. Observations: A 35-year-old, white, immunecompetent man was transferred from an outside facility with worsening dysarthria and confusion after having presented 4 weeks prior with dysarthria, gait ataxia, and bilateral upper extremity weakness. Brain magnetic resonance imaging revealed bilateral pontine strokes, and the working diagnosis was ischemic infarctions, presumed secondary to small vessel vasculitis. Cerebral spinal fluid (CSF) examination showed marked abnormalities including an elevated protein level (320 mg/dL), low glucose level (2 mg/dL), and high white blood cell count (330/ mm 3 ; 28% lymphocytes, 56% neutrophils, and 16% monocytes) suggestive of a bacterial, fungal, or tuberculosis meningitis. Empirical antibiotics and a second trial of intravenous steroids were started before infectious etiologies of meningitis were ultimately ruled out. Repeated magnetic resonance imaging of the brain revealed no evidence of new ischemic lesions. On hospital day 11, results of his CSF Histoplasma antigen and urine antigen tests were positive. His CSF culture also was positive for H capsulatum. The patient was treated initially with liposomal amphotericin B, 430 mg daily, but changed to voriconazole, 300 mg twice daily, secondary to renal insufficiency and eventually continued treatment with itraconazole cyclodextrin, 100 mg twice daily. Computed tomographic imaging revealed obstructive hydrocephalus, and a ventriculoperitoneal shunt was placed that successfully decompressed the ventricles. At 1 year, the patient demonstrated good clinical improvement and results of follow-up CSF cultures were negative. Conclusions and Relevance: While pulmonary involvement of histoplasmosis in immune-suppressed patients is common, systemic presentation of this fungal infection in immune-competent patients is rare and selflimiting. Isolated CNS histoplasmosis is exceedingly rare. Clinicians should consider CNS histoplasmosis in the differential diagnosis in atypical stroke cases, particularly those presenting with meningitis.

Background and Purpose-Stereotyped motor behaviors, known as "punding," originally described among amphetamine abusers have only recently been reported in Parkinson disease associated with both pro-(eg, levodopa) or anti-(eg, quetiapine) dopaminergic therapy. We describe a non-Parkinson disease case of nonpharmacologically induced punding as a complication of a brain stem cardiovascular accident. Summary of Case-A 54-year-old man, after an episode of brain stem cardiovascular accident secondary to basilar artery thrombosis, was noted to endlessly purchase and hoard food items and to write, copy and organize recipes. His activity was excessive, disruptive and affected his interaction with family members. The patient's punding behaviors significantly improved with an increased dose of sertraline from 100 mg to 150 mg per day. Conclusion-Our patient's presentation was most consistent with punding, but interestingly was not a result of dopaminergic therapy. Moreover, improvement of his behavior was noted with a selective serotonin reuptake inhibitor, further questioning the dopaminergic hypothesis of punding. Key Words: CVA Ⅲ hypergraphia Ⅲ punding Ⅲ sertraline Ⅲ stroke C omplex, prolonged and purposeless stereotyped motor behaviors, termed "punding" were originally adopted by Rylander in 1972 1 to describe these behaviors in amphetamine abusers. 1,2 It is characterized by an intense fascination with repetitive manipulations of technical equipment, the continual examining, handling, and sorting of common objects, hoarding and abnormally increased writing. 3,4,5 Punding is thought to be attributable to excess dopamine stimulation because similar behaviors can be induced by dopaminergic drugs in animals. 1,3,4 Increased writing activity (hypergraphia) is rarely seen in neurological illness but has been noted in patients with temporal lobe epilepsy, frontal lobe dementia, cerebrovascular disease or Parkinson disease (PD). 6 Here we report a case of punding presenting with hoarding and hypergraphia as a complication of a brain stem cerebrovascular accident (CVA). Case ReportsA 54-year-old right-handed man initially presented with sudden onset of right hemi-body numbness, dizziness, diplopia and nausea. He later developed left facial droop and dysarthria. On examination, the patient was alert and oriented to person, place, time, and situation. He was noted to have right hemi-anesthesia involving face, arm, and leg, left sixth and seventh cranial nerve palsy, and prominent nystagmus. There was otherwise no weakness. The MRI and MR angiography study was consistent with right pontine acute ischemic regions ( Figure 1) from a clot at the tip of basilar artery ( Figure 2). He was not on warfarin at time of admission.The past medical history was pertinent for hypertension, hypercholesterolemia, tobacco and alcohol abuse, and a possible transient ischemic attack. His psychiatric history was significant only for mild depression, which was well controlled on sertaline 100 mg per day.His discharge medications included: metoprolol ...