Construction and validation of a Parkinson's disease mutation genotyping array for the Parkin gene.

Parkin mutations account for the majority of familial and sporadic early onset Parkinson's disease (EOPD) cases with a known genetic association. More than 100 mutations have been described in the Parkin gene that includes homozygous, compound heterozygous, and single heterozygous mutations. We have designed a Parkin mutation genotyping array (gene chip) that includes published Parkin sequence variants and allows their simultaneous detection. The chip was validated by screening 85 PD cases and 47 controls previously tested for Parkin mutations. Similar genotyping microarrays have been developed for other genetically heterogeneous diseases including age-related macular degeneration. Here, we show the utility of a genotyping array for Parkinson's disease by analysis of 60 subjects from the Genetic Epidemiology of Parkinson Disease (GEPD) study that includes 15 early-onset PD case probands and 45 relatives.     

18F]-Dopa positron emission tomography imaging in early-stage, non-parkin juvenile parkinsonism.

There are few reports of positron emission tomography (PET) in juvenile parkinsonism (JP). We report on the results of (18)F-6-fluoro-L-dopa (FD) PET in a 14-year-old patient with JP of 5 years duration associated with atypical features. This is the youngest subject to be investigated to date. There was a severe asymmetric reduction in striatal FD uptake, with a rostrocaudal gradient in the putamen similar to that seen in adult-onset idiopathic parkinsonism. Extensive DNA analysis in this patient did not show mutations in the parkin gene.     

Detection of Parkin (PARK2) and DJ1 (PARK7) mutations in early-onset Parkinson disease: Parkin mutation frequency depends on ethnic origin of patients

Mutations in the Parkin (PARK2) and the DJ1 (PARK7) gene cause early-onset Parkinson disease (EOPD). We tested 75 Serbian EOPD patients for mutations in both genes by conventional mutational screening (SSCP/dHPLC/sequencing) to detect small sequence alterations and by gene dosage studies (quantitative PCR) to reveal deletions or multiplications of one or more exons. A compound heterozygous Parkin mutation (exon deletion and point mutation; [c.836_972del]+[c.1411C>T]; +1 is first nucleotide of GenBank AB009973.1) was identified in a patient who showed a relatively benign course after a disease onset at 41 years. Another case had a heterozygous exon deletion in DJ1 ([c.253_322del]+[?]) and presented with an age at onset of 45 years and a rapid disease course. In conclusion, Parkin mutations are surprisingly rare in our Serbian EOPD sample, suggesting that the mutation rate depends on the ethnic origin of the patients. Although DJ1 mutations appear to be rare, we confirm their role in EOPD and demonstrate the importance of gene dosage studies.     

MAT2A Inhibition Blocks the Growth of MTAP-Deleted Cancer Cells by Reducing PRMT5-Dependent mRNA Splicing and Inducing DNA Damage

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The neural basis for establishing a focal point in pure coordination games

When making a decision, humans often have to ‘coordinate’—reach the same conclusion—as another individual without explicitly communicating. Relatively, little is known about the neural basis for coordination. Moreover, previous fMRI investigations have supported conflicting hypotheses. One account proposes that individuals coordinate using a ‘gut feeling’ and that this is supported by insula recruitment. Another account proposes that individuals recruit strategic decision-making mechanisms in prefrontal cortex in order to coordinate. We investigate the neural basis for coordination in individuals with behavioral-variant frontotemporal dementia (bvFTD) who have limitations in social decision-making associated with disease in prefrontal cortex. We demonstrate that bvFTD are impaired at establishing a focal point in a semantic task (e.g. ‘Tell me any boy''s name’) that requires coordination relative to a similar, control semantic task that does not. Additionally, coordination limitations in bvFTD are related to cortical thinning in prefrontal cortex. These findings are consistent with behavioral economic models proposing that, beyond a ‘gut feeling’, strategic decision-making contributes to the coordination process, including a probabilistic mechanism that evaluates the salience of a response (e.g. is ‘John’ a frequent boy''s name), a hierarchical mechanism that iteratively models an opponent''s likely response and a mechanism involved in social perspective taking.     

Prevalence of mental disorder and impact on quality of life in inflammatory bowel disease

IntroductionDifferent studies have described psychiatric comorbidities in inflammatory bowel disease (IBD) patients, but most of them focus mainly on depression and anxiety. Even though major mental disorders are considered one of the main factors that decrease quality of life (QoL), its role in IBD patients remains unclear. We sought to identify the prevalence of different mental disorders as well as its relationship with QoL.Patients and methodsSubjects were recruited from the IBD Clinic. IBD Questionnaire 32 and structured clinical interview (SCID) for DMS-IV Text Revision were applied. Demographic and clinical data were collected via self-report questionnaires and medical records. The correlation between mental disorders and QoL (IBDQ-32 score) was evaluated using the Spearman correlation test.ResultsIn all, 104 patients were recruited, 12 with Crohn's disease, and 92 with ulcerative colitis. The prevalence of any major mental disorder was 56.7%: anxiety (44.2%), mood (27.9%), substance use (12.2%), and other psychiatric diagnoses (17.3%), and 29.8% of the patients presented three or more comorbid diagnoses. Mental Disorder (p = 0.005), mood disorder (p = 0.004), anxiety disorder (p = 0.009), were found to be significantly associated with lower QoL. Substance use disorder was associated with lower Digestive QoL (p = 0.01). Major depressive disorder (p = 0.004), social phobia (p = 0.03), PTSD (p = 0.02), and Generalized Anxiety Disorder (p < 0.001), were found to be significantly associated with lower QoL.ConclusionsIBD patients had important psychiatric comorbidity that significantly affects their QoL. These results warrant a systematic evaluation of psychiatric conditions in IBD patients.     

Salt appetite and the renin-angiotensin system: effect of oxytocin deficiency

To explore the role of oxytocin in the regulation of salt appetite and blood pressure, we conducted studies in oxytocin gene-knockout mice and determined (1) blood pressure and heart rate during day and night periods, (2) salt appetite after iso-osmotic volume depletion, and (3) salt appetite and blood pressure after central injection of angiotensin II. Long-term arterial catheters were inserted, and blood pressure and heart rate were recorded for 24 hours. There was a modest decrease in blood pressure and heart rate in knockout mice. Salt appetite was measured with a 2- bottle choice (water and 2% NaCl), with measurement of licking activity. Mice were injected subcutaneously with 30% polyethylene glycol (0.5 mL), and voluntary intakes were measured for 24 hours. Knockout mice consumed 3 times the amount of NaCl than did controls, 276+/-77 vs 90+/-38 licks/24 h (P<0.05). Water consumption was similar between groups. Angiotensin II (5, 50, and 200 ng/3 microL) injected intracerebroventricularly produced dose-related increases in intake, with no differences between the groups. The 50-ng dose of angiotensin II elicited salt and water intakes of 151+/-43 vs 160+/-33 licks and 250+/-53 vs and 200+/-51 licks, respectively (control vs knockout). The pressor response to angiotensin II was not different between the groups. Results suggest that oxytocin plays a role in the regulation of blood pressure and salt appetite, specifically as mediated by volume receptors, and that the renin-angiotensin system is not involved in these changes.     

Endosonographic features in patients with non-alcoholic early chronic pancreatitis improved with treatment at one year follow up

Since the prevention of early chronic pancreatitis (ECP) into chronic pancreatitis might be critical for the reduction of pancreatic cancer, we tried to clarify the pathophysiology of ECP patients, focusing on ECP patients without alcoholic chronic pancreatitis. 27 ECP patients without alcoholic chronic pancreatitis and 33 patients with functional dyspepsia with pancreatic enzyme abnormalities (FD-P) were enrolled in this study. Diagnosis of ECP was made when imaging findings showed the presence of more than 2 out of 7 endoscopic ultrasound features. Duodenal degranulated eosinophils and glucagon-like peptide 1 producing cells were estimated by immunostaining. There were no significant differences in characteristics and psychogenic factors between ECP and FD-P patients. Interestingly, endoscopic ultrasound score in ECP patients significantly improved, albeit clinical symptoms in ECP patients showed no improvement at one year follow up. The extent of migration of duodenal degranulated eosinophils in FD-P patients was significantly higher compared to that in ECP patients. The levels of elastase-1 and trypsin in ECP patients with improved endoscopic ultrasound features were significantly reduced by the treatment. Further studies will be needed to clarify whether clinical symptoms and endoscopic ultrasound features in ECP patients without alcoholic chronic pancreatitis were improved in longer follow up study.     

How cerebral cortex protects itself from interictal spikes: The alpha/beta inhibition mechanism

Interactions between interictal epileptiform discharges (IEDs) and distant cortical regions subserve potential effects on cognition of patients with focal epilepsy. We hypothesize that “healthy” brain areas at a distance from the epileptic focus may respond to the interference of IEDs by generating inhibitory alpha and beta oscillations. We predict that more prominent alpha‐beta oscillations can be found in patients with less impaired neurocognitive profile. We performed a source imaging magnetoencephalography study, including 41 focal epilepsy patients: 21 with frontal lobe epilepsy (FLE) and 20 with mesial temporal lobe epilepsy. We investigated the effect of anterior (i.e., frontal and temporal) IEDs on the oscillatory pattern over posterior head regions. We compared cortical oscillations (5–80 Hz) temporally linked to 3,749 IEDs (1,945 frontal and 1,803 temporal) versus an equal number of IED‐free segments. We correlated results from IED triggered oscillations to global neurocognitive performance. Only frontal IEDs triggered alpha‐beta oscillations over posterior head regions. IEDs with higher amplitude triggered alpha‐beta oscillations of higher magnitude. The intensity of posterior head region alpha‐beta oscillations significantly correlated with a better neuropsychological profile. Our study demonstrated that cerebral cortex protects itself from IEDs with generation of inhibitory alpha‐beta oscillations at distant cortical regions. The association of more prominent oscillations with a better cognitive status suggests that this mechanism might play a role in determining the cognitive resilience in patients with FLE.