Long non-coding RNA <Emphasis Type="Italic">H19</Emphasis> and <Emphasis Type="Italic">MALAT1</Emphasis> gene variants in patients with ischemic stroke in a northern Chinese Han population

Objectives Long non-coding RNAs (lncRNAs) have been identified as key regulators in the development of atherosclerosis, which is a major cause of ischemic stroke. However, to date, there are no reports on the association between lncRNA gene variation and the risk of ischemic stroke. Therefore, we assessed the association between H19 and MALAT1 gene polymorphisms and susceptibility to ischemic stroke in a northern Chinese Han population. Methods In our study, we genotyped four genetic variations in lncRNA-H19 and -MALAT1 (rs217727, rs2251375, rs619586, and rs3200401) in a case–control study of 567 ischemic stroke patients and 552 control subjects. Results We found that the TT genotype of the rs217727 polymorphism within H19 was significantly associated with increased risk of ischemic stroke in our northern Chinese Han population (odds ration (OR)?=?1.519, 95% confidence interval (CI)?=?1.072–2.152, p?=?0.018). Stratified analysis based on stroke subtype revealed that the increased risk was more evident in small vessel ischemic stroke (OR?=?1.941, 95% CI?=?1.260–2.992, p?=?0.02). Individuals with the TT genotype had a 1.941 times higher risk of small vessel ischemic stroke when compared with the subjects of CC?+?CT. These correlations remained after adjusting for confounding risk factors of stroke (OR?=?1.913, 95% CI?=?1.221–2.998, p?=?0.005). However, there was no significant association between H19 rs2251375 or MALAT1 rs3200401 and ischemic stroke in either total population analysis or subgroup analysis. Conclusion In conclusion, our findings suggest that the H19 rs217727 gene polymorphism contributes to small vessel ischemic stroke susceptibility in the Chinese Han population and may serve as a potential indicator for ischemic stroke susceptibility.     

Sequence analysis of <Emphasis Type="Italic">Drd2</Emphasis>, <Emphasis Type="Italic">Drd4</Emphasis>, and <Emphasis Type="Italic">Dat1</Emphasis> in SHR and WKY rat strains

Background  

The Spontaneously Hypertensive Rat (SHR) shows a number of behaviours that closely parallel those seen in children with attention-deficit hyperactivity disorder. These include motor hyperactivity, excessive responses under a fixed-interval/extinction schedule, difficulty in acquiring operant tasks and increased sensitivity to immediate behavioural reinforcement. As in children with ADHD, the behavioural and cognitive deficits in the SHR are responsive to stimulants, including d-amphetamine and d,l-methylphenidate. The non-hyperactive Wistar Kyoto (WKY) rat strain is often used as a control in behavioural studies of the SHR, and WKY itself has been suggested to be a useful animal model of depression. Numerous studies have shown that dopaminergic neurotransmission is altered between the two strains. Human genetic studies have found associations between several dopaminergic genes and both ADHD and depression.     

Mutation analysis of the Ras pathway genes<Emphasis Type="Italic"> NRAS</Emphasis>,<Emphasis Type="Italic"> HRAS</Emphasis>,<Emphasis Type="Italic"> KRAS</Emphasis> and<Emphasis Type="Italic"> BRAF</Emphasis> in glioblastomas

Aberrant activation of Ras signaling is a common finding in human glioblastomas. To determine the contribution of Ras gene mutations to this aberration, we screened 94 glioblastomas for mutations in the three Ras family genes NRAS, KRAS and HRAS. All tumors were additionally analyzed for mutations in BRAF, which encodes a Ras-regulated serine/threonine kinase with oncogenic properties. Mutation analysis of the entire coding regions of NRAS and KRAS, as well as the known mutation hot-spot sites in HRAS, identified somatic point mutations in two glioblastomas, both affecting codon 12 of NRAS (c.35G>A, p.G12D). Three additional tumors carried BRAF mutations altering the known hot-spot codon 599 (c.1796T>A, p.V599E). None of these five glioblastomas showed amplification of the EGFR or PDGFRA genes, while three of the tumors, including two with NRAS and one with BRAF mutation, demonstrated PTEN missense mutations or loss of PTEN mRNA expression. Taken together, our data suggest activating mutations in NRAS or BRAF as a molecular alteration that contributes to aberrant Ras signaling in a small fraction of glioblastomas.     

Association study of <Emphasis Type="Italic">interleukin 2</Emphasis> (<Emphasis Type="Italic">IL2</Emphasis>) and <Emphasis Type="Italic">IL4</Emphasis> with schizophrenia in a Japanese population

Interleukin 2 (IL-2) and IL-4 are pleiotropic cytokines regulating Th1/Th2 balance and have a regulatory activity in brain function. Thus these cytokines have been implicated in the pathophysiology of schizophrenia. The latest studies provided controversial results regarding the genetic associations of these cytokines. The functional polymorphisms, IL2-330T/G and IL4-590C/T, were associated with schizophrenia in a German population, although contradictory findings were also reported in a Korean population. To ascertain whether IL2 and IL4 contribute to vulnerability to schizophrenia, we conducted a moderate-scale case-control (536 patients and 510 controls) association study for seven polymorphisms in Japanese subjects. There were no significant associations of these genes with schizophrenia using either single marker or haplotype analyses. The present study suggests that IL2 and IL4 do not contribute to vulnerability to schizophrenia in the Japanese population.     

<Emphasis Type="Italic">c</Emphasis><Emphasis Type="Italic">-MYC</Emphasis> amplification and expression in astrocytic tumors

Point mutations and genomic multiplications in the α-synuclein (αSYN) gene cause autosomal-dominant Parkinson’s disease. Moreover, αSYN fibrils are the major component of Lewy bodies, the neuropathological hallmarks of Parkinson’s disease and dementia with Lewy bodies as well as of glial cytoplasmic inclusions in multiple system atrophy. These diseases are collectively referred to as α-synucleinopathies. Cellular mechanisms regulating αSYN fibril formation and toxicity are intensely studied in vitro, and in cell culture and diverse animal models. Specific neuropathology was achieved in transgenic mouse models using several promoters to express human wild-type and mutant αSYN in brain regions affected by the various α-synucleinopathies. Somatodendritic accumulation of the transgenic αSYN with neuritic distortions was a common finding. The nigrostriatal dopaminergic projections were surprisingly resistant to α-synucleinopathy in transgenic mice, although they tended to be more vulnerable to neurotoxins. In a few mouse models, αSYN aggregated in an age-dependent manner into genuine fibrillar amyloid. Brain region selective αSYN neuropathology correlated with specific behavioral impairments, such as locomotor dysfunction and cognitive decline. Thus, the αSYN fibrillization process is tightly linked to neuropathology. The role and thus therapeutic potential of post-translational modifications (ubiquitinylation, oxidation, phosphorylation, truncation) and modifier genes on αSYN neuropathology can now be assessed in valid transgenic mouse models of α-synucleinopathies.     

<Emphasis Type="Italic">DAT1</Emphasis> and <Emphasis Type="Italic">DRD4</Emphasis> genes involved in key dimensions of adult ADHD

Attention-deficit hyperactivity disorder (ADHD) is a highly heritable neurodevelopmental disorder often persisting in adulthood. Genetic studies of ADHD mainly focused on the Dopamine Transporter (DAT1) and the Dopamine Receptor 4 (DRD4) genes. Nevertheless, polymorphisms of these genes explain only a small fraction of the assigned risk, suggesting that intermediate dimensions and environmental factors should also be considered. We investigated in 77 adult ADHD subjects compared to 474 controls, how polymorphisms within the genes coding for DAT1 (40-bp VNTR in 3′UTR), the Dopamine Receptor 2 (DRD2) (rs1799732) and DRD4 (48-bp VNTR in exon 3), may modulate the expression of the disorder. By genotyping DAT1, we detected a new 9.5R allele showing a deletion of 40 bp and also an insertion of 19 bp compared to the 10R allele. This novel allele was found to be significantly protective for ADHD (p < 0.0001). Another significant difference was found in the distribution of DRD4 48-bp VNTR 6R allele when comparing patients and controls (p = 0.0007). In addition significant results were also found for DAT1 9.5R allele, which was associated with impulsiveness (p = 1.98 × 10^?4) and trait anger scores (p = 7.66 × 10^?4). Moreover, impulsiveness scores were partly modulated by an interaction between the DRD4 48-bp VNTR 6R allele and childhood maltreatment (p = 0.01), however, this result did not resist correction for multiple comparisons. Altogether, our results show the putative involvement of DAT1 and DRD4 genes in the aetiology of ADHD with a main role in modulation of key dimensions of the disorder.     

Association study of polymorphisms in synaptic vesicle-associated genes, <Emphasis Type="Italic">SYN2</Emphasis> and <Emphasis Type="Italic">CPLX2</Emphasis>, with schizophrenia

Background  

The occurrence of aberrant functional connectivity in the neuronal circuit is one of the integrative theories of the etiology of schizophrenia. Previous studies have reported that the protein and mRNA levels of the synapsin 2 (SYN2) and complexin 2 (CPLX2) genes were decreased in patients with schizophrenia. Synapsin 2 and complexin 2 are involved in synaptogenesis and the modulation of neurotransmitter release. This report presents a study of the association of polymorphisms of SYN2 and CPLX2 with schizophrenia in the Korean population.     

<Emphasis Type="Italic">CIC</Emphasis> and <Emphasis Type="Italic">FUBP1</Emphasis> mutations in oligodendrogliomas,oligoastrocytomas and astrocytomas

CIC and FUBP1 mutations have recently been detected in oligodendrogliomas but not in oligoastrocytomas. However, allelic losses in the regions on chromosomal arms 19q and 1p harboring CIC and FUBP1 are a common feature of both, oligodendrogliomas and oligoastrocytomas. To resolve this discrepancy, we analyzed CIC and FUBP1 mutations in a set of primary brain tumors including 18 oligodendrogliomas and 42 oligoastrocytomas. In addition, we analyzed 10 astrocytomas and 16 glioblastomas with allelic losses on 19q as well as a set of 12 medulloblastomas for CIC mutations. CIC mutations were found in 15/18 oligodendrogliomas, 14/42 oligoastrocytomas and 3/10 preselected astrocytomas. With the exception of a single case, all CIC mutations occurred in tumors with combined 1p/19q losses. In contrast to oligodendrogliomas where CIC mutations were always detected along with 1p/19q co-deletion, CIC mutations were only found in 52 % of the 1p/19q co-deleted oligoastrocytomas. FUBP1 mutations were detected in 7/61 tumors, all presenting with CIC mutations. FUBP1 mutations appear to cluster in the DNA binding domain spanning exons 5–14. CIC and FUBP1 mutations exclusively occurred in presence of either IDH1 or IDH2 mutations. Our data confirm CIC and FUBP1 mutations in oligodendrogliomas and demonstrate the presence of these mutations in oligoastrocytomas.     

Association of <Emphasis Type="Italic">CILP</Emphasis>, <Emphasis Type="Italic">COL9A2</Emphasis> and <Emphasis Type="Italic">MMP3</Emphasis> Gene Polymorphisms with Lumbar Disc Degeneration in an Indian Population

Lumbar disc degeneration (LDD) is a multifactorial disorder caused by genetic and environmental factors. Polymorphisms in several structural and inflammatory genes like collagens, aggrecan, matrix metalloproteinases are associated with the risk of disc degeneration. In this study, we analyzed the role of a few important single nucleotide polymorphisms in cartilage intermediate layer protein (CILP), collagen 9A2 (COL9A2) and matrix metalloproteinase 3 (MMP3) genes in LDD from an Indian population. Two hundred patients with LDD and 200 healthy controls were recruited for the study. Genotyping was performed by allelic discrimination assay. The rs2073711 polymorphism (CILP gene - GG genotype) was associated with reduced risk of LDD in the Indian population (OR?=?0.43, p?=?0.016). The rs591058 polymorphism (MMP3 gene - TT genotype) is found to be associated with lower risk among women (OR?=?0.34, p?=?0.041). No significant association was found between COL9A2 polymorphism rs7533552 and the risk of LDD. We conclude that the CILP gene polymorphism (rs2073711) is associated with a lower risk of LDD, the MMP3 (rs591058) gene polymorphism is associated with LDD among women, and the TT genotype confers a lower risk of LDD.     

Coexistence of <Emphasis Type="Italic">CLCN1</Emphasis> and <Emphasis Type="Italic">SCN4A</Emphasis> mutations in one family suffering from myotonia

Non-dystrophic myotonias are characterized by clinical overlap making it challenging to establish genotype-phenotype correlations. We report clinical and electrophysiological findings in a girl and her father concomitantly harbouring single heterozygous mutations in SCN4A and CLCN1 genes. Functional characterization of N1297S hNav1.4 mutant was performed by patch clamp. The patients displayed a mild phenotype, mostly resembling a sodium channel myotonia. The CLCN1 c.501C>G (p.F167L) mutation has been already described in recessive pedigrees, whereas the SCN4A c.3890A>G (p.N1297S) variation is novel. Patch clamp experiments showed impairment of fast and slow inactivation of the mutated Nav1.4 sodium channel. The present findings suggest that analysis of both SCN4A and CLCN1 genes should be considered in myotonic patients with atypical clinical and neurophysiological features.     

<Emphasis Type="Italic">ZNF804A</Emphasis> rs1344706 interacts with <Emphasis Type="Italic">COMT</Emphasis> rs4680 to affect prefrontal volume in healthy adults

The biological function of ZNF804A rs1344706, the first genome-wide supported risk variant of schizophrenia, remains largely unknown. Based on the upregulating effect of ZNF804A on the expression of COMT, we hypothesize that ZNF804A may affect grey matter volume (GMV) by interacting with COMT. Voxel-based morphometry was applied to analyze the main and interaction effects of ZNF804A rs1344706 and COMT rs4680 on brain GMV in 274 healthy young human subjects. The GMV of the left dorsolateral prefrontal cortex (DLPFC) showed a significant COMT rs4680 × ZNF804A rs1344706 interaction, manifesting as an inverted U-shape modulation by the presumed dopamine signaling. In COMT Met-allele carriers, the ZNF804A TG heterozygotes showed greater GMV in the left DLPFC than both GG and TT homozygotes. In COMT Val/Val homozygotes, however, the ZNF804A TG heterozygotes exhibited smaller GMV in the left DLPFC than GG homozygotes and comparable GMV with TT homozygotes. These findings suggest that ZNF804A affects the GMV of the prefrontal cortex by interacting with COMT, which may improve our understanding of neurobiological effect of ZNF804A and its association with schizophrenia.     

<Emphasis Type="Italic">Clostridium septicum</Emphasis> Pneumocephalus

Background

Spontaneous pneumocephalus in the nontraumatic setting is distinctly unusual. Pneumocephalus from central nervous system infection with Clostridium septicum has been rarely reported, and more commonly reflects a later stage of abscess formation. We present an unusual case of invasive C. septicum infection without an associated diagnosed malignancy presenting with rapidly progressive CNS pathology and resultant early pneumocephalus.

Methods

Medical records, radiologic imaging, and microbiological specimens of a case were reviewed.

Results

A 66-year-old male presented with a history of two witnessed generalized tonic–clonic seizures on awakening. He was found unresponsive at the scene by paramedics and subsequently intubated. There was no reported antecedent symptomatology, such as headache, fever, chills, focal weakness, and speech or gait disturbances. Medical history was remarkable only for diet-controlled hypertension. Computed tomography (CT) head imaging revealed an abnormal right parietal hypodensity. The patient was evaluated per the acute stroke protocol but was not deemed a candidate for intervention or thrombolytic therapy given the uncertainty of his clinical presentation; intravenous antibiotics were administered for possible sepsis. Follow-up CT imaging of the head performed 8 h later revealed right parieto-temporal pneumocephalus with extensive cerebral edema and effacement of basilar cisterns. Neurosurgical intervention was not deemed appropriate given the catastrophic nature of his injury and the patient subsequently expired 14 h after presentation. Blood cultures grew gram-positive rods in three of four bottles identified as C. septicum.

Conclusions

Clostridium septicum is an uncommon and often fatal cause of nontraumatic pneumocephalus. This underscores the need for a high index of clinical suspicion in cases with unexplained pneumocephalus, as early diagnosis remains the key to survival. In survivors of C. septicum infection, subsequent colonoscopy should be considered to exclude undiagnosed or occult gastrointestinal malignancy.

     

Variations in <Emphasis Type="Italic">Disrupted</Emphasis>-<Emphasis Type="Italic">in</Emphasis>-<Emphasis Type="Italic">Schizophrenia 1</Emphasis> gene modulate long-term longitudinal differences in cortical thickness in patients with a first-episode of psychosis

Schizophrenia patients typically present a widespread bilateral cortical thinning from the early stages of the illness. However, there is controversy whether this reduction in cortical thickness (CT) is static or progressive over the evolution of the disorder. Disrupted-in-Schizophrenia 1 (DISC1) is one of the main candidates genes for schizophrenia, as it has been found associated to the illness, and to several endophenotypes of the disorder including structural brain differences. This gene is known to be involved in neurodevelopment and brain maturation processes. We therefore hypothesized that variations in this gene modulate different progressions of CT in psychosis. Seventy-nine Caucasian drug-naive patients experiencing a first episode of non-affective psychosis were genotyped for rs6675281 (Leu607Phe) and rs821616 (Ser704Cys) SNPs of the DISC1 gene. Brain MRIs were carried out at baseline and 3 years after initiating the treatment. Other clinical and socio-demographic variables were recorded to rule out possible confounding effects. Patients homozygous for the Leu allele of the rs6675281 SNP had a significant (p?<?0.05) descend in CT over the 3-years period, while those carrying the Phe allele presented an increase in CT. When combining the two SNPs we found a synergic effect on CT progression, presenting those patients homozygous for Leu607 +Ser704 a more pronounced cortical thinning. In conclusion, DISC1 gene variations may modulate the longitudinal changes in cortical thickness in patients suffering from a first episode of non-affective psychosis.     

Update Anti-<Emphasis Type="Italic">N</Emphasis>-Methyl-<Emphasis Type="Italic">D</Emphasis>-Aspartat-Rezeptor-Enzephalitis

Autoimmune encephalitis is a group of autoimmune inflammatory disorders affecting both grey and white matter of the central nervous system. Encephalitis with autoantibodies against the N?methyl-D-aspartate receptor (NMDA-R) is the most frequent autoimmune encephalitis syndrome presenting with a characteristic sequence of psychiatric and neurological symptoms. Treatment necessitates a close interdisciplinary cooperation. This article provides an update on the current knowledge on diagnostic standards, pathogenesis, and treatment strategies for anti-NMDA-R encephalitis from psychiatric and neurological perspectives.