Unaffected Subjects Research Articles

Dicentric Chromosome Assay (DCA) and Cytokinesis-Block Micronucleus (CBMN) Assay in the Field of Biological Dosimetry.

Biological dosimetry is an essential tool for estimating radiation doses received from individuals when the physical dosimetry is not available or inadequate. Early knowledge about the absorbed dose levels in radiation accidents is of paramount importance for selecting the unaffected subjects from those individuals requiring medical evaluation and intervention. A lesson learned from many radiological incidents is the importance to identify the "worried well."Several assays are useful for biological dosimetry approaches, since no one single assay is sufficiently robust for all potential radiation scenarios including early-phase acute exposures, partial-body exposures, and biosampling years after exposure or in case of suspected mixed exposures (radiological and chemicals).The most commonly used biodosimetry methods are based on the evaluation of the radiation-specific dicentric chromosomes (Dic) and micronuclei (MN) in exposed individuals' peripheral blood lymphocytes (PBL).The present chapter does not claim to make an exhaustive and complete picture on the complex world of biodosimetry, to which a large number of specific guidelines for performing laboratory services by the International Organization for Standardization (ISO) are dedicated, but it aims to support the reader in understanding the application of two cytogenetic methods in the individual ionizing radiation dose assessment, suggesting some appropriate scientific sources to consult for each case.

Inflammatory biomarkers in psychosis and clinical high risk populations

BackgroundImmunological, nutritional, and microbial factors have been implicated in the pathophysiology of schizophrenia, but the interrelationship among measures is understudied. In particular, an increase in the levels of the pro-inflammatory cytokine interleukin-6 (IL-6) is associated with all phases of the illness, and may be associated with other inflammatory markers.Vitamin D is a modulator of the immune system, and LPS antibodies are an indirect measure of gut barrier function. In this study we investigated potential contributing inflammatory mechanisms for IL-6 elevation. MethodsWe compared the levels of vitamin D, C-reactive protein (CRP), antibodies to lipopolysaccharide (LPS), and IL-6 in children, adolescents and young adults with psychosis (n = 47), individuals at clinical high risk for psychosis (n = 17) and unaffected comparison controls (n = 33). Participants were diagnosed by a psychiatrist, using a structured interview, the MINI-Neuropsychiatric Interview. 25(OH)D was measured in serum using chemiluminescent micro particle immunoassay, and anti-LPS antibodies, CRP and IL-6 levels were measured by ELISA. ResultsIL-6 and C-reactive protein levels were significantly elevated in the psychosis group relative to the unaffected control subjects. In the psychosis group, levels of IL-6 correlated positively with IgA anti-LPS antibodies and negatively correlated with vitamin D. ConclusionsOur findings show a significant correlation between IL-6, anti-LPS antibodies and vitamin D deficiency in psychosis, suggesting the existence of multiple potential pathways related to IL-6 elevation in psychosis, and therefore multiple potential strategies for risk mitigation. Collectively these findings support hypotheses regarding interrelated inflammatory contributions to the pathophysiology of psychosis.

Morphological study of the changes after sagittal split ramus osteotomy in patients with facial asymmetry: measurements of 3-dimensional modelling

The effects of bilateral sagittal split ramus osteotomy (BSSRO) on the temporomandibular joint (TMJ) are still not well understood. The aim of this study was to compare the morphological differences among unaffected subjects on the one hand, and patients with facial asymmetry before and after BSSRO on the other. Ten Chinese patients (preoperative and postoperative groups, mean (SD) age 25 (5) years) diagnosed with facial asymmetry and 10 unaffected subjects (control group, mean (SD) age 27 (5) years) were recruited prospectively. The 3-dimensional morphological measurements made on 3-dimensional models in each group were assessed by analysis-of-variance (ANOVA) and Student’s t test, and probabilities of <0.05 were accepted as significant. The horizontal condylar angle (HCA), coronal condylar angle (CCA), sagittal ramus angle (SRA), medial joint space (MJS), lateral joint space (LJS), and superior joint space (SJS) differed significantly between the preoperative and control groups (HCA: p=0.000, CCA: p=0.000, SRA(left/undeviated side): p=0.002, MJS(left/undeviated side): p=0.000, MJS(right/deviated side): p=0.007, LJS(right/deviated side): p=0.000, SJS(left/undeviated side): p=0.000, SJS(right/deviated side): p=0.000). The SRA, MJS, LJS, and SJS differed significantly between the preoperative and postoperative groups (SRA(left/undeviated side): p=0.012, MJS(left/undeviated side): p=0.002, LJS(right/deviated side): p=0.021, SJS(left/undeviated side): p=0.000, SJS(right/deviated side): p=0.001), And the SRA, MJS, and LJS in the preoperative group differed significantly between the deviated and undeviated side (SRA: p=0.006; MJS: p=0.003; LJS: p=0.011). However, there were no significant differences in the postoperative and control groups between the deviated and undeviated sides. BSSRO improved the asymmetrical morphology of the TMJ and alleviated the symptoms.

Tobacco use and psychosis risk in persons at clinical high risk.

To evaluate the role of tobacco use in the development of psychosis in individuals at clinical high risk. The North American Prodrome Longitudinal Study is a 2-year multi-site prospective case control study of persons at clinical high risk that aims to better understand predictors and mechanisms for the development of psychosis. The cohort consisted of 764 clinical high risk and 279 healthy comparison subjects. Clinical assessments included tobacco and substance use and several risk factors associated with smoking in general population studies. Clinical high risk subjects were more likely to smoke cigarettes than unaffected subjects (light smoking odds ratio [OR] = 3.0, 95% confidence interval [CI] = 1.9-5; heavy smoking OR = 4.8, 95% CI = 1.7-13.7). In both groups, smoking was associated with mood, substance use, stress and perceived discrimination and in clinical high risk subjects with childhood emotional neglect and adaption to school. Clinical high risk subjects reported higher rates of several factors previously associated with smoking, including substance use, anxiety, trauma and perceived discrimination. After controlling for these potential factors, the relationship between clinical high risk state and smoking was no longer significant (light smoking OR = 0.9, 95% CI = 0.4-2.2; heavy smoking OR = 0.3, 95% CI = 0.05-2.3). Moreover, baseline smoking status (hazard ratio [HR] = 1.16, 95% CI = 0.82-1.65) and categorization as ever smoked (HR = 1.3, 95% CI = 0.8-2.1) did not predict time to conversion. Persons at high risk for psychosis are more likely to smoke and have more factors associated with smoking than controls. Smoking status in clinical high risk subjects does not predict conversion. These findings do not support a causal relationship between smoking and psychosis.

Exome sequencing identifies gene variants and networks associated with extreme respiratory outcomes following preterm birth

BackgroundPrevious studies have identified genetic variants associated with bronchopulmonary dysplasia (BPD) in extremely preterm infants. However, findings with genome-wide significance have been rare, and not replicated. We hypothesized that whole exome sequencing (WES) of premature subjects with extremely divergent phenotypic outcomes could facilitate the identification of genetic variants or gene networks contributing disease risk.ResultsThe Prematurity and Respiratory Outcomes Program (PROP) recruited a cohort of > 765 extremely preterm infants for the identification of markers of respiratory morbidity. We completed WES on 146 PROP subjects (85 affected, 61 unaffected) representing extreme phenotypes of early respiratory morbidity. We tested for association between disease status and individual common variants, screened for rare variants exclusive to either affected or unaffected subjects, and tested the combined association of variants across gene loci. Pathway analysis was performed and disease-related expression patterns were assessed. Marginal association with BPD was observed for numerous common and rare variants. We identified 345 genes with variants unique to BPD-affected preterm subjects, and 292 genes with variants unique to our unaffected preterm subjects. Of these unique variants, 28 (19 in the affected cohort and 9 in unaffected cohort) replicate a prior WES study of BPD-associated variants. Pathway analysis of sets of variants, informed by disease-related gene expression, implicated protein kinase A, MAPK and Neuregulin/epidermal growth factor receptor signaling.ConclusionsWe identified novel genes and associated pathways that may play an important role in susceptibility/resilience for the development of lung disease in preterm infants.

Mitochondrial Dysregulation and Impaired Autophagy in iPSC-Derived Dopaminergic Neurons of Multiple System Atrophy.

SummaryMultiple system atrophy (MSA) is a progressive neurodegenerative disease that affects several areas of the CNS, whose pathogenesis is still widely unclear and for which an effective treatment is lacking. We have generated induced pluripotent stem cell-derived dopaminergic neurons from four MSA patients and four healthy controls and from two monozygotic twins discordant for the disease. In this model, we have demonstrated an aberrant autophagic flow and a mitochondrial dysregulation involving respiratory chain activity, mitochondrial content, and CoQ10 biosynthesis. These defective mechanisms may contribute to the onset of the disease, representing potential therapeutic targets.

Altered ErbB4 splicing and cortical parvalbumin interneuron dysfunction in schizophrenia and mood disorders.

Working memory requires the activity of parvalbumin (PV) interneurons in the dorsolateral prefrontal cortex (DLPFC). Impaired working memory and lower PV expression in the DLPFC are reported in schizophrenia and to a lesser degree in mood disorders. We previously proposed that activity-dependent PV expression is lower in schizophrenia due to a shift in the splicing of erb-b2 receptor tyrosine kinase 4 (ErbB4) transcripts from major to inactive minor variants that reduces excitatory drive to PV interneurons. Here, we tested the hypothesis that the degree of major-to-minor shift in ErbB4 splicing predicts the level of PV expression across schizophrenia and mood disorders. Levels of ErbB4 splice variants and PV mRNA were quantified by PCR in the DLPFC from 40 matched tetrads (N = 160 subjects) of schizophrenia, bipolar disorder (BD), major depressive disorder (MDD), and unaffected comparison subjects. Relative to unaffected comparison subjects, the magnitude of increases in minor variant levels and decreases in major variant levels was greatest in schizophrenia, intermediate in BD, and least in MDD. The same rank order was present for the magnitude of increases in the composite splicing score, which reflects the degree of major-to-minor shift across all ErbB4 splice loci, and for the magnitude of deficient PV expression. Finally, the composite splicing score negatively predicted PV expression across all subject groups. Together, these findings demonstrate a shared relationship between ErbB4 splicing and PV expression and suggest that scaling of the major-to-minor shift in ErbB4 splicing may influence the severity of deficient PV interneuron activity across diagnoses.

Synaptic Proteome Compensation and Resilience to Psychosis in Alzheimer's Disease.

The presence of psychosis in Alzheimer's disease denotes a phenotype with more rapid cognitive deterioration than in Alzheimer's disease without psychosis. Discovery of novel pharmacotherapies that engage therapeutic targets for prevention or treatment of Alzheimer's disease with psychosis would benefit from identifying the neurobiology of resilience to psychosis in Alzheimer's disease. The primary objective of this study was to determine whether alterations in the synaptic proteome were associated with resilience to psychotic symptoms in Alzheimer's disease and, if present, were independent of neuropathologic burden. Quantitative immunohistochemistry was used to measure multiple neuropathologies in dorsolateral prefrontal cortex from subjects with early and middle-stage Alzheimer's disease who differed in psychosis status. Synaptic proteins were quantified by liquid chromatography-mass spectrometry in gray matter homogenates from these subjects and from neuropathologically unaffected subjects. The synaptic proteome was similarly evaluated in cortical gray matter homogenate and in postsynaptic density fractions from an APPswe/PSEN1dE9 mouse model of amyloidosis with germline reduction in Kalrn, which has been shown to confer resilience to progression of psychosis-associated behaviors relative to APPswe/PSEN1dE9 alone. Subjects resilient to psychotic symptoms in Alzheimer's disease had higher levels of synaptic proteins compared with those with psychosis and unaffected control subjects. Neuropathologic burden predicted less than 20% of the variance in psychosis status and did not account for the synaptic protein level differences between groups. Reduction of Kalrn in APPswe/PSEN1dE9 mice resulted in higher levels of synaptic proteins in cortical homogenate and normalized protein levels in the postsynaptic density. Accumulation of synaptic proteins, particularly those that are enriched in the postsynaptic density, is associated with resilience to psychosis in Alzheimer's disease. One candidate mechanism for this synaptic proteome compensation is alteration in levels of proteins that facilitate the transport of synaptic proteins to and from the postsynaptic density.

Dental Anomalies in Different Types of Cleft Lip and Palate: Is There Any Relation?

The aims of this study were to evaluate the prevalence of dental anomalies in Turkish patients with different types of cleft lip and palate (CLP) and investigate the relationship between the type of cleft and the dental anomaly. Eighty-eight patients with cleft lip and/or palate (mean age: 14.1 ± 6.4 years) were enrolled in this retrospective study. Dental models, panoramic radiographs, and intraoral photographs of these patients were evaluated to detect any maxillary dental anomaly (number and size anomalies). Two hundred fifty unaffected subjects (mean age: 15.2 ± 7.2 years) composed the control group. Data were evaluated using the independent t test, χ, Fischer exact test, and the odds ratio. Dental anomaly frequency was significantly higher in the cleft group compared with the control group. Tooth agenesis was the most common dental anomaly, followed by microdontia and supernumerary tooth. Lateral incisor agenesis was seen in 69% of the unilateral CLP, in 78% of the bilateral CLP, and in 18% of the cleft palate patients. A significant association was revealed between the right unilateral CLP and the right lateral incisor agenesis (P = 0.0001), the left unilateral CLP and the left lateral incisor agenesis (P = 0.002), and the bilateral CLP and the bilateral lateral incisor agenesis (P = 0.0001). Dental anomalies are more frequently seen in patients with CLP compared with the general population. There is a relationship between the cleft type and the ipsilateral lateral incisor agenesis.

Dengue Fever Detecting System Using Peak-detection of Data from Contactless Doppler Radar.

Infectious diseases, such as dengue fever and Middle East respiratory syndrome, have become prevalent worldwide in recent times. To conduct highly accurate and effective infection screening, we are working on the development of a contactless infection screening system using Doppler radar and thermography. In our previous work, three parameters (face temperature, heartbeat rate, and respiration rate) were used to judge whether a subject was infected. However, facial temperature measurements may be vastly different from temperatures measured at the axilla owing to influence from the immediate environment. In this study, heartbeat rate (HR), respiration rate (RR), and standard deviation of heartbeat interval (SDHI) were used to quantify the infection screening system without using facial temperature as a parameter. We found that respiratory sinus arrhythmia (RSA) diminished in patients who had dengue fever. We gathered data from 47 patients with dengue fever using a 10-GHz Doppler radar system at the National Hospital of Tropical Diseases (NHTD) in Hanoi, Vietnam. To evaluate the accuracy, the data of these patients were compared to that of 23 unaffected subjects. We observed that a linear discriminant analysis (LDA) was effective at detecting the dengue fever conditions, and the detection accuracy was approximately 97.6%.

The Role of the Nuclear Factor-κB Transcriptional Complex in Cortical Immune Activation in Schizophrenia

BackgroundTranscript levels for cytokines and the viral restriction factor interferon-induced transmembrane protein are markedly higher in the prefrontal cortex in schizophrenia. These gene products are regulated by the nuclear factor-κB (NF-κB) transcriptional complex. NF-κB activity, which requires the formation of NF-κB family member heterodimers, is regulated by activation receptors, kinases, and inhibitors. Whether any of these factors are altered in schizophrenia is not known. It is also unclear whether NF-κB-related disturbances reflect ongoing cortical immune activation or a long-lasting response to a prenatal immune-related insult. MethodsTranscript levels for NF-κB pathway markers were assessed using quantitative polymerase chain reaction in the prefrontal cortex from 1) 62 matched pairs of schizophrenia and unaffected comparison subjects, 2) antipsychotic-exposed monkeys, and 3) adult mice exposed prenatally to maternal immune activation or in adulthood to the immune stimulant polyinosinic-polycytidylic acid. ResultsIn schizophrenia subjects, but not antipsychotic-exposed monkeys, we found higher messenger RNA levels for 1) most NF-κB family members, 2) all NF-κB activation receptors, 3) several kinases, and 4) one inhibitor (IκBα) whose transcript level is itself regulated by NF-κB activity. A similar pattern of elevated NF-κB-related messenger RNA levels was seen in adult mice that received daily polyinosinic-polycytidylic acid injections, but not in adult mice subjected to maternal immune activation in utero. ConclusionsHigher NF-κB activity, evidenced by elevated transcript levels for NF-κB family members, activation receptors, and kinases, may contribute to increased markers of cortical immune activation in schizophrenia.

Neopterin/7,8-dihydroneopterin is elevated in Duchenne muscular dystrophy patients and protects mdx skeletal muscle function.

What is the central question of this study? We examined whether the macrophage-synthesized antioxidant 7,8-dihydroneopterin was elevated in Duchenne muscular dystrophy (DMD) patients. We then examined whether 7,8-dihydroneopterin could protect dystrophic skeletal mouse muscle from eccentric contraction-induced force loss and improve recovery. What is the main finding and its importance? Urinary neopterin/creatinine and 7,8-dihydroneopterin/creatinine were elevated in DMD patients. 7,8-Dihydroneopterin attenuated eccentric contraction-induced force loss of dystrophic skeletal mouse muscle and accelerated recovery of force. These results suggest that eccentric contraction-induced force loss is mediated, in part, by an oxidative component and provides a potential protective role for 7,8-dihydroneopterin in DMD. Macrophage infiltration is a hallmark of dystrophin-deficient muscle. We tested the hypothesis that Duchenne muscular dystrophy (DMD) patients would have elevated levels of the macrophage-synthesized pterins, neopterin and 7,8-dihydroneopterin, compared with unaffected age-matched control subjects. Urinary neopterin/creatinine and 7,8-dihydroneopterin/creatinine were elevated in DMD patients, and 7,8-dihydroneopterin/creatinine was associated with patient age and ambulation. Urinary 7,8-dihydroneopterin corrected for specific gravity was also elevated in DMD patients. Given that 7,8-dihydroneopterin is an antioxidant, we then identified a potential role for 7,8-dihydroneopterin in disease pathology. We assessed whether 7,8-dihydroneopterin could: (i) protect against isometric force loss in wild-type skeletal muscle exposed to various pro-oxidants; and (ii) protect wild-type and mdx muscle from eccentric contraction-induced force loss, which has an oxidative component. Force loss was elicited in isolated extensor digitorum longus (EDL) muscles by 10 eccentric contractions, and recovery of force after the contractions was measured in the presence of exogenous 7,8-dihydroneopterin. 7,8-Dihydroneopterin attenuated isometric force loss by wild-type EDL muscles when challenged by H2 O2 and HOCl, but exacerbated force loss when challenged by SIN-1 (NO• , O2• , ONOO- ). 7,8-Dihydroneopterin attenuated eccentric contraction-induced force loss in mdx muscle. Isometric force production by EDL muscles of mdx mice also recovered to a greater degree after eccentric contractions in the presence of 7,8-dihydroneopterin. The results corroborate macrophage activation in DMD patients, provide a potential protective role for 7,8-dihydroneopterin in the susceptibility of dystrophic muscle to eccentric contractions and indicate that oxidative stress contributes to eccentric contraction-induced force loss in mdx skeletal muscle.

Prevalence and topographical characteristics of keratoconus in patients with refractive errors in the Egyptian delta

To study the prevalence of keratoconus (KC) and the topographical characteristics of the affected corneas in patients with refractive errors who were seeking refractive surgery in the Egyptian delta. A retrospective study covering four and half years (Jan 2012-June 2016) where the topographical data of 8124 participants were obtained from the records of a refractive center in the Nile delta region, Egypt. The diagnosis of KC was based on the Holladay criteria in one or both eyes, using the Pentacam scans, whereas grading of KC was based on the Amsler-Krumeich classification. The prevalence of KC was 1.12% (91/8124 participants) with 95% confidence interval 0.91-1.3. Of all the affected cases, 5 cases (5.5%) had unilateral, and the other 86 cases (94.5%) had bilateral KC. The affected and unaffected subjects did not show any significant difference regarding gender. Sixty-eight (38.4%) eyes had stage 1 KC, 53 eyes (29.9%) had stage 2, 27 eyes (15.3%) had stage 3, and 29 eyes (16.4%) had stage 4 KC. It was most prevalent (1.2%) among cases with astigmatism (P < 0.001). Keratoconus was found in 1.12% of patients seeking refractive surgery, with no gender preference. Most cases had bilateral affection. Astigmatism was the most common refractive error to be associated with keratoconus.

Assessment of the corticospinal fiber integrity in mirror movement disorder

Mirror movements are unintended movements occurring on one side of the body that mirror the contralateral voluntary ones. It has been proposed that mirror movements occur due to abnormal decussation of the corticospinal pathways. Using detailed multidisciplinary approach, we aimed to enlighten the detailed mechanism underlying the mirror movements in a case subject who is diagnosed with mirror movements of the hands and we compared the findings with the unaffected control subjects. To evaluate the characteristics of mirror movements, we used several techniques including whole exome sequencing, computed tomography, diffusion tensor imaging and transcranial magnetic stimulation. Computed tomography showed the absence of a spinous process of C5, fusion of the body of C5-C6 vertebrae, hypoplastic dens and platybasia of the posterior cranial fossa. A syrinx cavity was present between levels C3-C4 of the spinal cord. Diffusion tensor imaging of the corticospinal fibers showed disorganization and minimal decussations at the lower medulla oblongata. Transcranial magnetic stimulation showed that motor commands were distributed to the motor neuron pools on the left and right sides of the spinal cord via fast-conducting corticospinal tract fibers. Moreover, a heterozygous missense variation in the deleted in colorectal carcinoma gene has been observed. Developmental absence of the axonal guidance molecules or their receptors may result in abnormalities in the leading of the corticospinal fibers. Clinical evaluations and basic neuroscience techniques, in this case, provide information for this rare disease and contribute to our understanding of the normal physiology of bimanual coordination.

Networks of blood proteins in the neuroimmunology of schizophrenia

Levels of certain circulating cytokines and related immune system molecules are consistently altered in schizophrenia and related disorders. In addition to absolute analyte levels, we sought analytes in correlation networks that could be prognostic. We analyzed baseline blood plasma samples with a Luminex platform from 72 subjects meeting criteria for a psychosis clinical high-risk syndrome; 32 subjects converted to a diagnosis of psychotic disorder within two years while 40 other subjects did not. Another comparison group included 35 unaffected subjects. Assays of 141 analytes passed early quality control. We then used an unweighted co-expression network analysis to identify highly correlated modules in each group. Overall, there was a striking loss of network complexity going from unaffected subjects to nonconverters and thence to converters (applying standard, graph-theoretic metrics). Graph differences were largely driven by proteins regulating tissue remodeling (e.g. blood-brain barrier). In more detail, certain sets of antithetical proteins were highly correlated in unaffected subjects (e.g. SERPINE1 vs MMP9), as expected in homeostasis. However, for particular protein pairs this trend was reversed in converters (e.g. SERPINE1 vs TIMP1, being synthetical inhibitors of remodeling of extracellular matrix and vasculature). Thus, some correlation signals strongly predict impending conversion to a psychotic disorder and directly suggest pharmaceutical targets.

Dysbindin-1 contributes to prefrontal cortical dendritic arbor pathology in schizophrenia

Deep layer III pyramidal cells in the dorsolateral prefrontal cortex (DLPFC) from subjects with schizophrenia and bipolar disorder previously were shown to exhibit dendritic arbor pathology. This study sought to determine whether MARCKS, its regulatory protein dysbindin-1, and two proteins, identified using microarray data, CDC42BPA and ARHGEF6, were associated with dendritic arbor pathology in the DLPFC from schizophrenia and bipolar disorder subjects. Using western blotting, relative protein expression was assessed in the DLPFC (BA 46) grey matter from subjects with schizophrenia (n = 19), bipolar disorder (n = 17) and unaffected control subjects (n = 19). Protein expression data were then correlated with dendritic parameter data obtained previously. MARCKS and dysbindin-1a expression levels did not differ among the three groups. Dysbindin-1b expression was 26% higher in schizophrenia subjects (p = 0.01) and correlated inversely with basilar dendrite length (r = −0.31, p = 0.048) and the number of spines per basilar dendrite (r = −0.31, p = 0.048), but not with dendritic spine density (r = −0.16, p = 0.32). The protein expression of CDC42BPA was 33% higher in schizophrenia subjects (p = 0.03) but, did not correlate with any dendritic parameter (p > 0.05). ARHGEF6 87 kDa isoform expression did not differ among the groups. CDC42BPA expression was not altered in frontal cortex from rats chronically administered haloperidol or clozapine. Dysbindin-1b appears to play a role in dendritic arbor pathology observed previously in the DLPFC in schizophrenia.

Electrocardiographic T-wave parameters in families with long QT syndrome.

T-wave parameters, especially the Tpeak-Tend interval (TpTe), reflect the total dispersion of repolarization, whose amplification may lead to the development of life-threatening ventricular arrhythmias observed in the long QT syndrome (LQTS). The study attempted to evaluate QT, QTp (Q-Tpeak) and TpTe (Tpeak-Tend) intervals in unaffected and affected blood relatives of children with clinically confirmed LQTS as well as to determine whether the values of these repolarization parameters may be used in clinical practice. The study group included 47 affected blood relatives (27 LQTS1 and 20 LQTS2) and 68 unaffected family members without clinically confirmed LQTS symptoms. The TpTe, QT and QTp intervals were measured manually in the lead V5 of standard ECGs and corrected using Bazett's and Fridericia's formulas. The RR, QT, QTp and TpTe intervals with their corrected values were significantly longer (p < 0.0001) in the affected subjects than in the unaffected subjects and, similarly, in LQTS1 and LQTS2 patients compared with the unaffected family members. The TpTe interval in LQTS2 showed only a tendency to be longer compared to LQTS1, but did not reach statistical significance (p = 0.0933). For affected blood relatives, only the TpTe interval (p < 0.0409) and QT interval, corrected with Bazett's (p < 0.0393) and Fridericia's (p < 0.0495) formulas, enabled differentiation between LQTS1 (mean TpTe = 103 ±15) and LQTS2 women (mean TpTe = 106 ±17). Moreover, there were statistically significant differences (p < 0.05) in the TpTe interval between the 6 sex subgroups: unaffected women and men as well as women and men with LQTS1 and LQTS2. The electrocardiographic Tpeak-Tend parameter, in addition to the QT interval, is helpful in identifying affected blood relatives of children with LQTS, particularly for the group of LQTS1 and LQTS2 women. Further studies are required to assess the clinical importance of the TpTe interval in families with long QT syndrome.

Improving the genetic signature of prostate cancer, the somatic mutations

BackgroundSomatic mutations have been related to the highest incidence of metastatic disease and different treatment responses. The molecular cause of prostate cancer (PC) is still unclear; however, its progression involves alterations in oncogenes and tumor suppressor genes as well as somatic mutations such as the ones in PIK3CA gene. A high percentage of PC is considered sporadic, which means that the damage to the genes occurs by chance after birth (mainly somatic mutations will drive the cancer event). However, little is known about somatic mutations in PC development. Materials and methodsWe evaluated prostate biopsies in the main somatic mutations genes (PIK3CA, TP53, EGFR, KIT, KRAS, PTEN, and BRAF) among individuals with PSA values>4ng/ml (n = 125), including affected and unaffected PC subjects. ResultsMutations in KIT gene are related to aggressive PC: TNM stages II to III, Gleason score ≥ 7 and D’Amico risk (P = 0.037, 0.040, and 0.017). However, there are no statistical significant results when more than 3 somatic mutations are presented in the same individual. In relation to environmental factors (smoking, diet, alcohol intake, or workplace exposure) there are no significant differences in the effect of environmental exposure and the somatic mutation presence. The most prevalent mutations among patients with PC are c.1621A>C (rs3822214) in KIT, c.38G>C (rs112445441) in KRAS and c.733G>A (rs28934575) in TP53 genes. KRAS, KIT, and TP53 genes are the most prevalent ones in patients with PC. ConclusionsSomatic alterations predisposing to chromosomal rearrangements in PC remain largely undefined. We show that KIT, KRAS, and TP53 genes have a higher presence among patients with PC and that mutations in KIT gene are related to an aggressive PC. However, we did not find any environmental effect in somatic mutations among PC individuals.

18.1 MITOCHONDRIAL ALTERATIONS WITHIN THE PYRAMIDAL-PARVALBUMIN CELL MICROCIRCUIT IN THE PREFRONTAL CORTEX IN SCHIZOPHRENIA

BackgroundWorking memory, a core cognitive function impaired in schizophrenia, depends upon gamma oscillatory neuronal activity in the prefrontal cortex (PFC). Accordingly, individuals with schizophrenia show lower power of gamma oscillations in the PFC during tasks that involve working memory. Gamma oscillations emerge from the fast and coordinated activity of layer 3 excitatory pyramidal cells and inhibitory parvalbumin (PV) cells. As such, gamma oscillations have a particularly high energetic demand that is met by ATP production via oxidative phosphorylation (OXPHOS) within pyramidal and PV cell mitochondria. PFC layer 3 pyramidal cells have prominent reductions in OXPHOS-related gene pathways in schizophrenia. Importantly, OXPHOS can be regulated by two distinct processes: ATP demand to support neuronal firing, or upstream deficits in OXPHOS enzyme expression. Layer- and cell type-specific transcriptomic analyses of OXPHOS enzymes and ultrastructural analyses of mitochondrial morphology can help to distinguish between these two possibilities. Reduced ATP demand due to reduced neuronal firing is associated with 1) correlated expression levels of OXPHOS enzyme complexes, 2) lower expression of all subunits comprising Complex IV, the terminal and rate-limiting OXPHOS enzyme complex, and 3) normal mitochondrial morphology. Defective OXPHOS results in 1) elimination of correlated expression of OXPHOS enzyme complexes, 2) variable and inconsistent effects on Complex IV subunit expression, and 3) abnormal mitochondrial morphology.To determine which upstream factor is likely operative in the illness, we quantified OXPHOS enzyme complex transcripts in layer 3 pyramidal and PV cells, and performed ultrastructural analyses of mitochondrial morphology within pyramidal and PV axon boutons in layer 3 of the PFC in schizophrenia and unaffected comparison subjects.MethodsFor mRNA analyses, frozen tissue sections of area 9 from 36 pairs of schizophrenia and comparison subjects were stained for Nissl substance to identify pyramidal cells, or labeled using immunoperoxidase for aggrecan to identify PV cells. Layer 3 pyramidal and PV somata were dissected using laser capture microdissection. Transcriptome profiling was performed by microarray using Affymetrix GeneChips. Analysis of Complexes I, IV, and V expression in each neuronal population was assessed at q<0.05 in covariate- and multiple comparisons-corrected analyses.Electron microscopic analyses were performed in area 46 of 2 matched pairs of schizophrenia and comparison subjects. Mitochondria in pyramidal and PV cell boutons were classified as normal or abnormal using established criteria. Chi-square analysis was used to examine whether the percentages of each type differed between groups.ResultsThe expression of subunits comprising Complexes I, IV, and V in layer 3 pyramidal and PV cells was significantly lower in subjects with schizophrenia relative to unaffected comparison subjects. In both cell populations, expression of Complexes I, IV, and V were correlated (r=0.8-0.9) in unaffected comparison and schizophrenia subjects. Complex IV subunits showed 11–26% reductions in pyramidal cells, and 7-31% reductions in PV cells in schizophrenia. In both unaffected comparison and schizophrenia subjects, ≥99% of mitochondria in pyramidal cell boutons and ≥97% of mitochondria in PV cell boutons exhibited normal morphology.DiscussionThe current findings are most consistent with the interpretation that lower measures of OXPHOS in schizophrenia reflect lower demand for ATP production due to less neuronal firing.

39.1 DNA METHYLATION OF IMMUNE CELLS IN PERSONS AT CLINICAL HIGH RISK FOR PSYCHOSIS

BackgroundA dysregulated immune system is implicated in the development of psychotic disorders. Persons with schizophrenia have altered levels of circulating immune cell signaling molecules (cytokines), and elevation of specific cytokines predict conversion to psychosis in persons at clinical high risk. Whether these peripheral signals are a causal or a secondary phenomenon is unclear. But, subpopulations of circulating immune cells do regulate the brain from meningeal and perivascular locations influencing cognition, mood, and behavior, and thus may be relevant to schizophrenia vulnerability. Hematopoietic stem cells in the bone marrow differentiate into cascading subtypes depending on signals from other organs, especially the brain. For example, a monocyte subpopulation emerges with repeated social defeat that establish the persistence of anxiety-like behaviors; blocking their release or inhibiting their attachment to brain vascular endothelium prevents the emergence of anxiety-like behaviors. In humans, a similar monocyte subpopulation is associated with social isolation and other adversities including low SES, chronic stress, and bereavement.MethodsThe North American Prodrome Longitudinal Study (NAPLS2) is an eight-site observational study of predictors and mechanisms of conversion to psychosis The full cohort includes 763 at clinical high risk (CHR) based on the Criteria of Prodromal State (COPS) and 279 demographically similar unaffected comparison (UC) subjects. Methylation of whole blood DNA collected in PAXgene tubes at baseline was analyzed with the Illumina 450k array in a subgroup of 59 subjects who converted to psychosis (CHR-C), 84 CHR subjects followed for 2 years who did not develop psychosis (CHR-NC) and 67 unaffected subjects (UC). Our analyses focused on methylation of promoter regions of genes, associated with gene expression. Classifier construction used Coarse Approximation Linear Function (CALF) with bootstrapping of 1000 random 80% subsets with replacement to determine statistical likelihood.ResultsWe found highly overlapping sets of differentially methylated promoter regions in CHR-C subjects compared to CHR-NC and to UC subjects. A set of 10 markers correctly classified CHR-C and CHR-NC subjects with high accuracy (AUC=0.94, 95% CI 0.89–0.98). Included was SIRT1, a gene that is upregulated with HSV reactivation.DiscussionCirculating immune cells excerpt powerful influences on mood, cognition and behavior. An obvious example is the experience of most human with “sickness syndrome”, characterized by apathy, avolition, and withdrawal, and triggered by immune-cell-released cytokines producing an adaptive, resource conserving, behavioral response. While at an early stage, our findings further implicate immune system dysregulation as a mechanism in the development of psychosis.