Alexander Mao

Neuronal Differentiation and Growth Control of Neuro-2a Cells After Retroviral Gene Delivery of Connexin43

Given the roles proposed for gap junctional intercellular communication in neuronal differentiation and growth control, we examined the effects of connexin43 (Cx43) expression in a neuroblastoma cell line. A vesicular stomatitis virus G protein (VSVG)-pseudotyped retrovector was engineered to co-express the green fluorescent protein (GFP) and Cx43 in the communication-deficient neuro-2a (N2a) cell line. The 293 GPG packaging cell line was used to produce VSVG-pseudotyped retrovectors coding for GFP, Cx43, or chimeric Cx43·GFP fusion protein. The titer of viral supernatant, as measured by flow cytometry for GFP fluorescence, was approximately 2.0 × 107 colony form units (CFU)/ml and was free of replication-competent retroviruses. After a 7-day treatment with retinoic acid (20 μm), N2a transformants (N2a-Cx43 and N2a-Cx43·GFP) maintained the expression of Cx43 and Cx43·GFP. Expression of both constructs resulted in functional coupling, as evidenced by electrophysiological and dye-injection analysis. Suppression of cell growth correlated with expression of both Cx43 or Cx43·GFP and retinoic acid treatment. Based on morphology and immunocytochemistry for neurofilament, no difference was observed in the differentiation of N2a cells compared with cells expressing Cx43 constructs. In conclusion, constitutive expression of Cx43 in N2a cells does not alter retinoic acid-induced neuronal differentiation but does enhance growth inhibition.

SLT and adjunctive medical therapy: a prediction rule analysis.

PurposeTo investigate if specific classes of antiglaucoma medications have an influence on selective laser trabeculoplasty (SLT) success. MethodsThis retrospective prediction rule analysis investigated 120 eyes from 120 patients diagnosed with either open angle glaucoma or ocular hypertension, who underwent SLT treatment. Treatment success was defined as ≥20% intraocular pressure (IOP) reduction at 3 and 6 months after the treatment date. Multivariate logistic regression analyses were performed to determine success predictors. ResultsPre-SLT IOP (up to 4 wk before SLT therapy) was the only independent predictor for ≥20% IOP reduction with an odds ratio of 1.30 when controlling for pre-SLT antiglaucoma drops. The area under receiver operator characteristic curve was 0.777. ConclusionsTopical medications do not adversely, nor favorably, affect SLT success. SLT efficacy is positively associated with the degree of IOP elevation before SLT treatment. Pigmentation of the anterior chamber angle, class of antiglaucoma medications, diabetes, sex, corneal thickness, pseudophakia, diagnosis, washout of eye drops, and previous argon laser trabeculoplasty treatment are not associated with SLT treatment efficacy.

Development of a prediction rule to estimate the probability of acceptable intraocular pressure reduction after selective laser trabeculoplasty in open-angle glaucoma and ocular hypertension.

PurposeTo develop and validate a prediction rule to estimate the probability of acceptable intraocular pressure (IOP) reduction after selective laser trabeculoplasty (SLT) in ocular hypertension and open-angle glaucoma. Patients and MethodsThe study population was derived from a cohort of 220 patients with ocular hypertension, open-angle glaucoma, or normal tension glaucoma. A ≥20% reduction in IOP (mm Hg) from the baseline IOP at 6 months after SLT was considered treatment success. Logistic multivariate regression modeling was performed to develop a prediction rule. ResultsIn multivariate logistic regression analyses, pre-SLT IOP and maximum IOP were identified as independent predictors for ≥20% IOP reduction at 6 months with adjusted odds ratios of 1.3 and 0.9, respectively, controlling for sex, diagnosis, pigment of anterior chamber, and washout of eye drops. The area under receiver operator characteristic curve was 0.716. Calibration of this prediction rule showed good agreement between predicted and observed probabilities of acceptable IOP reduction. If a probability of acceptable IOP reduction of 50% or greater is used as the minimal clinical threshold for treatment, the prediction rule had a sensitivity and specificity of 91.3% and 30.4%, respectively. ConclusionsSLT efficacy is positively associated with IOP elevation before SLT treatment and adversely associated with the maximum IOP ever recorded in history. Pigmentation of the anterior chamber angle, diagnosis, washout of eye drops, and sex are not associated with SLT treatment efficacy. This prediction rule should be further validated with a comparable prospective clinical study cohort.

“Blindsight” and subjective awareness of fearful faces: Inversion reverses the deficits in fear perception associated with core psychopathic traits

Though emotional faces preferentially reach awareness, the present study utilised both objective and subjective indices of awareness to determine whether they enhance subjective awareness and “blindsight”. Under continuous flash suppression, participants localised a disgusted, fearful or neutral face (objective index), and rated their confidence (subjective index). Psychopathic traits were also measured to investigate their influence on emotion perception. As predicted, fear increased localisation accuracy, subjective awareness and “blindsight” of upright faces. Coldhearted traits were inversely related to subjective awareness, but not “blindsight”, of upright fearful faces. In a follow-up experiment using inverted faces, increased localisation accuracy and awareness, but not “blindsight”, were observed for fear. Surprisingly, awareness of inverted fearful faces was positively correlated with coldheartedness. These results suggest that emotion enhances both pre-conscious processing and the qualitative experience of awareness, but that pre-conscious and conscious processing of emotional faces rely on at least partially dissociable cognitive mechanisms.