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Investigation of Somatic GNAQ, GNA11, BAP1 and SF3B1 Mutations in Ophthalmic Melanocytomas. - Ocular oncology and pathology
The aim of this study was to use massively parallel DNA sequencing to identify GNAQ/11, BAP1 and SF3B1 mutations in ophthalmic melanocytoma.Six ophthalmic melanocytoma specimens (1 iridociliary and 5 optic nerve) were profiled for genomic alterations in GNAQ/11, BAP1 and SF3B1 using a custom deep sequencing assay. This assay uses solution phase hybridization-based exon capture and deep-coverage massively parallel DNA sequencing to interrogate all protein-coding exons and select introns.The only iridociliary melanocytoma showed a mutation in GNAQ but not in BAP1. Of the 2 optic-nerve melanocytomas that developed into melanoma, one had a GNAQ mutation and both a BAP1 mutation and monosomy 3. The remaining 3 optic-nerve melanocytomas did not reveal mutations in GNAQ/11 or BAP1. SF3B1 mutations were not detected in any specimen.The presence of GNAQ mutation in some iridociliary and optic-nerve melanocytomas suggests a possible relationship between ophthalmic melanocytoma and other ophthalmic melanocytic neoplasms. BAP1 mutation may accompany the transformation of ophthalmic melanocytoma to melanoma.
Orbito-Masticatory Syndrome. - Journal of neuro-ophthalmology : the official journal of the North American Neuro-Ophthalmology Society
We describe 2 unique cases of visual symptoms occurring during mastication in patients with lateral orbital wall defects. A 57-year-old man reported intermittent double vision and oscillopsia after a right fronto-temporal-orbito-zygomatic craniotomy with osteotomy of the lesser wing of the sphenoid for a complex invasive pituitary adenoma. Proptosis of the right globe was present only during mastication. Computed tomography (CT) revealed a bony defect in the right lateral orbital wall. A 48-year-old man presented with transient diplopia and scotoma in the right eye elicited by chewing. CT and magnetic resonance imaging demonstrated a bilobed lesion connecting the temporal fossa to the orbit through a defect in the right lateral orbital wall. The regional neuroanatomy and pathophysiology as pertaining to these cases are discussed.
Extensive Replication of a Retroviral Replicating Vector Can Expand the A Bulge in the Encephalomyocarditis Virus Internal Ribosome Entry Site and Change Translation Efficiency of the Downstream Transgene. - Human gene therapy methods
We have developed retroviral replicating vectors (RRV) derived from Moloney murine gammaretrovirus with an amphotropic envelope and an encephalomyocarditis virus (EMCV) internal ribosome entry site (IRES)-transgene cassette downstream of the env gene. During long-term (180 days) replication of the vector in animals, a bulge of 7 adenosine residues (A's) in the J-K bifurcation domain sometimes serially added A's. Therefore, vectors with 4-12 A's in the A bulge in the J-K bifurcation domain were generated, and the impact of the variants on transgene protein expression, vector stability, and IRES sequence upon multiple infection cycles was assessed in RRV encoding yeast-derived cytosine deaminase and green fluorescent protein in vitro. For transgene protein expression, after multiple infection cycles, RRV-IRES with 5-7 A's gave roughly comparable levels, 4 and 8 A's were within about 4-5-fold of the 6 A's, whereas 10 and 12 A's were marked lower. In terms of stability, after 10 infection cycles, expansion of A's appeared to be a more frequent event affecting transgene protein expression than viral genome deletions or rearrangement: 4 and 5 A's appeared completely stable; 6, 7, and particularly 8 A's showed some level of expansion in the A bulge; 10 and 12 A's underwent both expansion and transgene deletion. The strong relative translational activity of the 5 A's in the EMCV IRES has not been reported previously. The 5A RRV-IRES may have utility for preclinical and clinical applications where extended replication is required.
Diagnostic quality assessment of compressed sensing accelerated magnetic resonance neuroimaging. - Journal of magnetic resonance imaging : JMRI
To determine the efficacy of compressed sensing (CS) reconstructions for specific clinical magnetic resonance neuroimaging applications beyond more conventional acceleration techniques such as parallel imaging (PI) and low-resolution acquisitions.Raw k-space data were acquired from five healthy volunteers on a 3T scanner using a 32-channel head coil using T2 -FLAIR, FIESTA-C, time of flight (TOF), and spoiled gradient echo (SPGR) sequences. In a series of blinded studies, three radiologists independently evaluated CS, PI (GRAPPA), and low-resolution images at up to 5Ã— accelerations. Synthetic T2 -FLAIR images with artificial lesions were used to assess diagnostic accuracy for CS reconstructions.CS reconstructions were of diagnostically acceptable quality at up to 4Ã— acceleration for T2 -FLAIR and FIESTA-C (average qualitative scores 3.7 and 4.3, respectively, on a 5-point scale at 4Ã— acceleration), and at up to 3Ã— acceleration for TOF and SPGR (average scores 4.0 and 3.7, respectively, at 3Ã— acceleration). The qualitative scores for CS reconstructions were significantly better than low-resolution images for T2 -FLAIR, FIESTA-C, and TOF and significantly better than GRAPPA for TOF and SPGR (Wilcoxon signed rank test, P < 0.05) with no significant difference found otherwise. Diagnostic accuracy was acceptable for both CS and low-resolution images at up to 3Ã— acceleration (area under the ROC curve 0.97 and 0.96, respectively.) CONCLUSION: Mild to moderate accelerations are possible for those sequences by a combined CS and PI reconstruction. Nevertheless, for certain sequences/applications one might mildly reduce the acquisition time by appropriately reducing the imaging resolution rather than the more complicated CS reconstruction. J. Magn. Reson. Imaging 2016.Â© 2016 Wiley Periodicals, Inc.
Mouse Model of Chromosome 15q13.3 Microdeletion Syndrome Demonstrates Features Related to Autism Spectrum Disorder. - The Journal of neuroscience : the official journal of the Society for Neuroscience
The chromosome 15q13.3 microdeletion is a pathogenic copy number variation conferring epilepsy, intellectual disability, schizophrenia, and autism spectrum disorder (ASD). We generated mice carrying a deletion of 1.2 Mb homologous to the 15q13.3 microdeletion in human patients. Here, we report that mice with a heterozygous deletion on a C57BL/6 background (D/+ mice) demonstrated phenotypes including enlarged/heavier brains (macrocephaly) with enlarged lateral ventricles, decreased social interactions, increased repetitive grooming behavior, reduced ultrasonic vocalizations, decreased auditory-evoked gamma band EEG, and reduced event-related potentials. D/+ mice had normal body weight, activity levels, sensory gating, and cognitive abilities and no signs of epilepsy/seizures. Our results demonstrate that D/+ mice represent ASD-related phenotypes associated with 15q13.3 microdeletion syndrome. Further investigations using this chromosome-engineered mouse model may uncover the common mechanism(s) underlying ASD and other neurodevelopmental/psychiatric disorders representing the 15q13.3 microdeletion syndrome, including epilepsy, intellectual disability, and schizophrenia.Recently discovered pathologic copy number variations (CNVs) from patients with neurodevelopmental/psychiatric disorders show very strong penetrance and thus are excellent candidates for mouse models of disease that can mirror the human genetic conditions with high fidelity. A 15q13.3 microdeletion in humans results in a range of neurodevelopmental/psychiatric disorders, including epilepsy, intellectual disability, schizophrenia, and autism spectrum disorder (ASD). The disorders conferred by a 15q13.3 microdeletion also have overlapping genetic architectures and comorbidity in other patient populations such as those with epilepsy and schizophrenia/psychosis, as well as schizophrenia and ASD. We generated mice carrying a deletion of 1.2 Mb homologous to the 15q13.3 microdeletion in human patients, which allowed us to investigate the potential causes of neurodevelopmental/psychiatric disorders associated with the CNV.Copyright Â© 2015 the authors 0270-6474/15/3516282-13$15.00/0.
Environmental enrichment facilitates cocaine-cue extinction, deters reacquisition of cocaine self-administration and alters AMPAR GluA1 expression and phosphorylation. - Addiction biology
This study investigated the combination of environmental enrichment (EE) with cocaine-cue extinction training on reacquisition of cocaine self-administration. Rats were trained under a second-order schedule for which responses were maintained by cocaine injections and cocaine-paired stimuli. During three weekly extinction sessions, saline was substituted for cocaine but cocaine-paired stimuli were presented. Rats received 4-h periods of EE at strategic time points during extinction training, or received NoEE. Additional control rats received EE or NoEE without extinction training. One week later, reacquisition of cocaine self-administration was evaluated for 15 sessions, and then GluA1 expression, a cellular substrate for learning and memory, was measured in selected brain regions. EE provided both 24â€‰h before and immediately after extinction training facilitated extinction learning and deterred reacquisition of cocaine self-administration for up to 13 sessions. Each intervention by itself (EE alone or extinction alone) was ineffective, as was EE scheduled at individual time points (EE 4â€‰h or 24â€‰h before, or EE immediately or 6â€‰h after, each extinction training session). Under these conditions, rats rapidly reacquired baseline rates of cocaine self-administration. Cocaine self-administration alone decreased total GluA1 and/or pSer845GluA1 expression in basolateral amygdala and nucleus accumbens. Extinction training, with or without EE, opposed these changes and also increased total GluA1 in ventromedial prefrontal cortex and dorsal hippocampus. EE alone increased pSer845GluA1 and EE combined with extinction training decreased pSer845GluA1 in ventromedial prefrontal cortex. EE might be a useful adjunct to extinction therapy by enabling neuroplasticity that deters relapse to cocaine self-administration.Â© 2015 Society for the Study of Addiction.
Dissociations in Cortical Morphometry in Youth with Down Syndrome: Evidence for Reduced Surface Area but Increased Thickness. - Cerebral cortex (New York, N.Y. : 1991)
Detailed descriptions of cortical anatomy in youth with Down syndrome (DS), the most common genetic cause of intellectual disability (ID), are scant. Thus, the current study examined deviations in cortical thickness (CT) and surface area (SA), at high spatial resolution, in youth with DS, to identify focal differences relative to typically developing (TD) youth. Participants included 31 youth with DS and 45 age- and sex-matched TD controls (mean age âˆ¼16 years; range = 5-24 years). All participants completed T1-weighted ASSET-calibrated magnetization prepared rapid gradient echo scans on a 3-T magnetic resonance imaging scanner. Replicating prior investigations, cortical volume was reduced in DS compared with controls. However, a novel dissociation for SA and CT was found-namely, SA was reduced (predominantly in frontal and temporal regions) while CT was increased (notably in several regions thought to belong to the default mode network; DMN). These findings suggest that reductions in SA rather than CT are driving the cortical volume reductions reported in prior investigations of DS. Moreover, given the link between DMN functionality and Alzheimer's symptomatology in chromosomally typical populations, future DS studies may benefit from focusing on the cortex in DMN regions, as such investigations may provide clues to the precocious onset of Alzheimer's disease in this at-risk group.Published by Oxford University Press 2015. This work is written by (a) US Government employee(s) and is in the public domain in the US.
Preexisting Levels of CD4 T Cells Expressing PD-1 Are Related to Overall Survival in Prostate Cancer Patients Treated with Ipilimumab. - Cancer immunology research
Cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4) blockade can induce tumor regression and improved survival in cancer patients. This treatment can enhance adaptive immune responses without an exogenous vaccine, but the immunologic biomarkers associated with improved clinical outcome in cancer patients are not fully established. A phase Ib trial in patients with metastatic, castration-resistant prostate cancer was performed combining ipilimumab with sargramostim (GM-CSF). In addition to evaluating ipilimumab dose, patients were followed clinically for response and overall survival, and for immunomodulation of circulating T cells. PSA declines of â‰¥50% and radiographic responses were observed at doses of â‰¥3 mg/kg/dose. Timing of clinical responses could be either immediate or delayed. Durable responses were also observed off treatment. A subset of patients experienced long-term survival with or without objective clinical responses. The relationship between T-cell phenotype in peripheral blood and overall survival was examined retrospectively. We found that the treatment induced an increase in the levels of CD4(+) effector T (Teff) cells, regulatory T cells, PD-1(+) CD4 Teff cells, and PD-1(+) CD8 T cells. However, these increased levels were not associated with overall survival. Instead, low pretreatment baseline levels of PD-1(+) CD4 Teff cells were found to correlate with longer overall survival. Furthermore, baseline levels of PD-1(+) CD4 Teff cells from patients with shorter overall survival were higher than from cancer-free male control subjects. These results suggest that preexisting expression of immunologic checkpoint marker PD-1 on CD4 Teff cells may help identify patients that may benefit from ipilimumab treatment.Â©2015 American Association for Cancer Research.
Fungal Orbital Cellulitis: Presenting Features, Management and Outcomes at a Referral Center. - Orbit (Amsterdam, Netherlands)
To report a series of patients with fungal orbital cellulitis who underwent exenteration surgery and describe presenting features, management and outcomes at a referral center.Retrospective case series.From November 2011 to March 2014, four patients underwent orbital exenteration for fungal orbital cellulitis at the University of Illinois. Three patients had mucormycosis and one had aspergillosis. All patients were treated with intravenous antifungals and underwent orbital exenteration. Two patients were successfully treated with supplemental intra-orbital catheter delivery of amphotericin B. Presenting visual acuity in the affected eye ranged from 20/25 to no light perception. Some level of ophthalmoplegia was present in three patients. Significantly elevated intraocular pressure was found in two patients. All patients with mucormycosis were found to have uncontrolled diabetes mellitus. One patient had a history of myelodysplastic syndrome, chronic hepatitis C infection, polysubstance abuse and Crohn's disease. Another patient had a history of alcoholic liver cirrhosis, Crohn's disease treated with systemic immunosuppression and renal cell carcinoma. The patient with aspergillosis had myelodysplastic syndrome and portal hypertension, and the initial presentation resembled giant cell arteritis. Two of four patients died during their hospitalization.Fungal orbital cellulitis has a high mortality rate despite aggressive antifungal treatment and orbital exenteration performed soon after the diagnosis is confirmed. Patients often have a history of immunosuppression and the onset may be insidious. There must be a high rate of suspicion for fungal orbital cellulitis given the appropriate signs and medical history in order to avoid treatment delay.
Proteolytic cleavage of ataxin-7 promotes SCA7 retinal degeneration and neurological dysfunction. - Human molecular genetics
The neurodegenerative disorder spinocerebellar ataxia type 7 (SCA7) is caused by a polyglutamine (polyQ) expansion in the ataxin-7 protein, categorizing SCA7 as one member of a large class of heritable neurodegenerative proteinopathies. Cleavage of ataxin-7 by the protease caspase-7 has been demonstrated in vitro, and the accumulation of proteolytic cleavage products in SCA7 patients and mouse models has been identified as an early pathological change. However, it remains unknown whether a causal relationship exists between ataxin-7 proteolysis and in vivo SCA7 disease progression. To determine whether caspase cleavage is a critical event in SCA7 disease pathogenesis, we generated transgenic mice expressing polyQ-expanded ataxin-7 with a second-site mutation (D266N) to prevent caspase-7 proteolysis. When we compared SCA7-D266N mice with SCA7 mice lacking the D266N mutation, we found that SCA7-D266N mice exhibited improved motor performance, reduced neurodegeneration and substantial lifespan extension. Our findings indicate that proteolysis at the D266 caspase-7 cleavage site is an important mediator of ataxin-7 neurotoxicity, suggesting that inhibition of caspase-7 cleavage of polyQ-ataxin-7 may be a promising therapeutic strategy for this untreatable disorder.Â© The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: firstname.lastname@example.org.
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