Relatively higher norms of blood flow velocity of major intracranial arteries in North-West Iran

<p>Abstract</p> <p>Background</p> <p>Transcranial Doppler (TCD) is a noninvasive, less expensive and harmless hemodynamic study of main intracranial arteries. The aim of this study was to assess normal population values of cerebral blood flow velocity and its variation over age and gender in a given population.</p> <p>Findings</p> <p>Eighty healthy volunteers including 40 people with an age range of 25-40 years (group1) and 40 persons with an age range of 41-55 years (group2) were studied. In each group 20 males and 20 females were enrolled. Peak systolic, end diastolic and mean velocities of nine main intracranial arteries were determined using TCD. Mean age of the studied volunteers was 31.6 ± 4.50 years in group one and 47.2 ± 4.3 years in group two. Mean age among males was 40 years and among females it was 39. Mean blood flow velocity in middle, anterior and posterior cerebral arteries, vertebral and basilar arteries was 60 ± 8, 52 ± 9, 42 ± 6, 39 ± 8 and 48 ± 8 cm/sec respectively. Cerebral blood flow velocities among females were relatively higher than males. Cerebral blood flow velocity of left side was relatively higher than right side.</p> <p>Conclusion</p> <p>Compared to previous studies, cerebral blood flow velocity in this population was relatively higher.</p

Genomic Characterization of Host Factors Related to SARS-CoV-2 Infection in People with Dementia and Control Populations: The GR@ACE/DEGESCO Study

Emerging studies have suggested several chromosomal regions as potential host genetic factors involved in the susceptibility to SARS-CoV-2 infection and disease outcome. We nested a COVID-19 genome-wide association study using the GR@ACE/DEGESCO study, searching for susceptibility factors associated with COVID-19 disease. To this end, we compared 221 COVID-19 confirmed cases with 17,035 individuals in whom the COVID-19 disease status was unknown. Then, we performed a meta-analysis with the publicly available data from the COVID-19 Host Genetics Initiative. Because the APOE locus has been suggested as a potential modifier of COVID-19 disease, we added sensitivity analyses stratifying by dementia status or by disease severity. We confirmed the existence of the 3p21.31 region (LZTFL1, SLC6A20) implicated in the susceptibility to SARS-CoV-2 infection and TYK2 gene might be involved in COVID-19 severity. Nevertheless, no statistically significant association was observed in the COVID-19 fatal outcome or in the stratified analyses (dementia-only and non-dementia strata) for the APOE locus not supporting its involvement in SARS-CoV-2 pathobiology or COVID-19 prognosis

Genomic Characterization of Host Factors Related to SARS-CoV-2 Infection in People with Dementia and Control Populations: The GR@ACE/DEGESCO Study

Emerging studies have suggested several chromosomal regions as potential host genetic factors involved in the susceptibility to SARS-CoV-2 infection and disease outcome. We nested a COVID-19 genome-wide association study using the GR@ACE/DEGESCO study, searching for susceptibility factors associated with COVID-19 disease. To this end, we compared 221 COVID-19 confirmed cases with 17,035 individuals in whom the COVID-19 disease status was unknown. Then, we performed a meta-analysis with the publicly available data from the COVID-19 Host Genetics Initiative. Because the APOE locus has been suggested as a potential modifier of COVID-19 disease, we added sensitivity analyses stratifying by dementia status or by disease severity. We confirmed the existence of the 3p21.31 region (LZTFL1, SLC6A20) implicated in the susceptibility to SARS-CoV-2 infection and TYK2 gene might be involved in COVID-19 severity. Nevertheless, no statistically significant association was observed in the COVID-19 fatal outcome or in the stratified analyses (dementia-only and non-dementia strata) for the APOE locus not supporting its involvement in SARS-CoV-2 pathobiology or COVID-19 prognosis

CIBERER : Spanish national network for research on rare diseases: A highly productive collaborative initiative

Altres ajuts: Instituto de Salud Carlos III (ISCIII); Ministerio de Ciencia e Innovación.CIBER (Center for Biomedical Network Research; Centro de Investigación Biomédica En Red) is a public national consortium created in 2006 under the umbrella of the Spanish National Institute of Health Carlos III (ISCIII). This innovative research structure comprises 11 different specific areas dedicated to the main public health priorities in the National Health System. CIBERER, the thematic area of CIBER focused on rare diseases (RDs) currently consists of 75 research groups belonging to universities, research centers, and hospitals of the entire country. CIBERER's mission is to be a center prioritizing and favoring collaboration and cooperation between biomedical and clinical research groups, with special emphasis on the aspects of genetic, molecular, biochemical, and cellular research of RDs. This research is the basis for providing new tools for the diagnosis and therapy of low-prevalence diseases, in line with the International Rare Diseases Research Consortium (IRDiRC) objectives, thus favoring translational research between the scientific environment of the laboratory and the clinical setting of health centers. In this article, we intend to review CIBERER's 15-year journey and summarize the main results obtained in terms of internationalization, scientific production, contributions toward the discovery of new therapies and novel genes associated to diseases, cooperation with patients' associations and many other topics related to RD research

Common variants in Alzheimer’s disease and risk stratification by polygenic risk scores

Funder: Funder: Fundación bancaria ‘La Caixa’ Number: LCF/PR/PR16/51110003 Funder: Grifols SA Number: LCF/PR/PR16/51110003 Funder: European Union/EFPIA Innovative Medicines Initiative Joint Number: 115975 Funder: JPco-fuND FP-829-029 Number: 733051061Genetic discoveries of Alzheimer's disease are the drivers of our understanding, and together with polygenetic risk stratification can contribute towards planning of feasible and efficient preventive and curative clinical trials. We first perform a large genetic association study by merging all available case-control datasets and by-proxy study results (discovery n = 409,435 and validation size n = 58,190). Here, we add six variants associated with Alzheimer's disease risk (near APP, CHRNE, PRKD3/NDUFAF7, PLCG2 and two exonic variants in the SHARPIN gene). Assessment of the polygenic risk score and stratifying by APOE reveal a 4 to 5.5 years difference in median age at onset of Alzheimer's disease patients in APOE ɛ4 carriers. Because of this study, the underlying mechanisms of APP can be studied to refine the amyloid cascade and the polygenic risk score provides a tool to select individuals at high risk of Alzheimer's disease

New insights into the genetic etiology of Alzheimer's disease and related dementias

Characterization of the genetic landscape of Alzheimer's disease (AD) and related dementias (ADD) provides a unique opportunity for a better understanding of the associated pathophysiological processes. We performed a two-stage genome-wide association study totaling 111,326 clinically diagnosed/'proxy' AD cases and 677,663 controls. We found 75 risk loci, of which 42 were new at the time of analysis. Pathway enrichment analyses confirmed the involvement of amyloid/tau pathways and highlighted microglia implication. Gene prioritization in the new loci identified 31 genes that were suggestive of new genetically associated processes, including the tumor necrosis factor alpha pathway through the linear ubiquitin chain assembly complex. We also built a new genetic risk score associated with the risk of future AD/dementia or progression from mild cognitive impairment to AD/dementia. The improvement in prediction led to a 1.6- to 1.9-fold increase in AD risk from the lowest to the highest decile, in addition to effects of age and the APOE ε4 allele

Multiancestry analysis of the HLA locus in Alzheimer’s and Parkinson’s diseases uncovers a shared adaptive immune response mediated by HLA-DRB1*04 subtypes

Across multiancestry groups, we analyzed Human Leukocyte Antigen (HLA) associations in over 176,000 individuals with Parkinson’s disease (PD) and Alzheimer’s disease (AD) versus controls. We demonstrate that the two diseases share the same protective association at the HLA locus. HLA-specific fine-mapping showed that hierarchical protective effects of HLA-DRB1*04 subtypes best accounted for the association, strongest with HLA-DRB1*04:04 and HLA-DRB1*04:07, and intermediary with HLA-DRB1*04:01 and HLA-DRB1*04:03. The same signal was associated with decreased neurofibrillary tangles in postmortem brains and was associated with reduced tau levels in cerebrospinal fluid and to a lower extent with increased Aβ42. Protective HLA-DRB1*04 subtypes strongly bound the aggregation-prone tau PHF6 sequence, however only when acetylated at a lysine (K311), a common posttranslational modification central to tau aggregation. An HLA-DRB1*04-mediated adaptive immune response decreases PD and AD risks, potentially by acting against tau, offering the possibility of therapeutic avenues

Description of series of 10 patients with hypnic headache: discussion of the diagnostic criteria

Introduction: Hypnic headache is a rare primary headache. The diagnostic criteria of the International Headache Classification (IHS) for this condition are discussed, as they have been modified in the new edition of the 2013. Patients and methods: The clinical characteristics, and fulfilment of the criteria of the IHS classification in a series of 10 patients diagnosed in our Headaches Clinic, are analysed. Results: The mean age of onset of symptoms was 52.1 years (SD: 13.4; range: 28–69). The pain was reported as oppressive in 60% of the patients, and as sharp in 30%. The headache was described as holocranial in 60% and hemicranial in 40%. They occurred exclusively during night-time sleep in 80% of the patients. The mean duration of headache was 136.5 minutes (range: 10–480). The mean number of days per month was 16.4 (range: 3–30), and 50% had less than 15 headache days per month. No patient had autonomic manifestations, 70% had phonophobia, 50% had photophobia, and 50% had both. All of them (100%) had a VAS score equal to or higher than 8. Conclusions: The criteria for hypnic headache of the new classification are best suited to the characteristics of these patients. Our results show the major changes in the criteria: pain is not always dull, headache frequency may be less than 15 days a month, and it can occur in people under age 50. There may be phonophobia or photophobia only, or both. Although it does not form part of the diagnostic criteria, the pain intensity in our series was higher than described. Resumen: Introducción: La cefalea hípnica es una cefalea primaria poco frecuente. Los criterios diagnósticos de la Clasificación Internacional de Cefaleas (CIC) para esta entidad han sido discutidos, por lo que en la nueva edición de la CIC de 2013 se han modificado. Pacientes y métodos: Analizamos las características clínicas y la adecuación a los criterios de la CIC de una serie de 10 pacientes diagnosticados en nuestra consulta de cefaleas. Resultados: La edad media de inicio del cuadro fue 52,1 años (DE: 13,4; rango: 28–69). El 60% de nuestros pacientes describían el dolor como opresivo y el 30% como punzante. En el 60% es holocraneal y en el 40% es hemicraneal. Al 80% les ocurre exclusivamente durante el sueño nocturno. La duración media de la cefalea es de 136,5 min (rango: 10–480). La media de días al mes es de 16.4 (rango: 3–30) y el 50% presentaron cefalea menos de 15 días al mes. Ningún paciente presentó manifestaciones autonómicas, el 70% presentó sonofobia y el 50% fotofobia. El 50% presentó ambas. El 100% puntuó la intensidad en la escala VAS igual o superior a 8. Conclusiones: Los criterios para cefalea hípnica de la nueva CIC se adecuan mejor a las características de estos pacientes. Nuestros resultados reflejan los principales cambios en los criterios: el dolor no siempre es sordo, puede aparecer menos de 15 días al mes y en personas de menos de 50 años. Puede existir sonofobia y fotofobia y no solo uno de ellos. Aunque no forma parte de los criterios diagnósticos, nos ha llamado la atención que en nuestra serie la intensidad es mayor a la descrita. Keywords: Hypnic headache, Diagnostic criteria, Sleep, International headache classification, Palabras clave: Cefalea hípnica, Criterios diagnósticos, Sueño, Clasificación internacional de cefalea

Evaluación preliminar de una versión pictórica y abreviada del Free and Cued Selective Reminding Test.

A picture version of the Free and Cued Selective Reminding Test (FCSRT) would assist in the assessment of memory function in patients with low levels of schooling. A shortened version would improve the test's applicability. To analyse the diagnostic usefulness of a shortened picture version of the FCSRT for distinguishing patients with amnestic mild cognitive impairment (aMCI) from controls, without excluding participants with a low level of schooling. Phase I study of a diagnostic evaluation (convenience sampling; pre-test prevalence 50%). A blinded researcher independently administered the FCSRT to 30 patients with aMCI and 30 controls matched for age, sex, level of schooling and literacy, using images and omitting the usual 30-minute delayed recall item. Three variables were recorded: free recall, total recall, and cue efficiency. Diagnostic accuracy was calculated using receiver operating characteristic curves and the area under the curve. The Youden index was used to identify optimal cut-off points. Of all participants, 41.7% had not completed primary education. There were no differences between groups as regards sociodemographic variables. Area under the curve was excellent for free recall (0.99), total recall (0.95), and cue efficiecy (0.93). The optimal cut-off points were 21/22, 43/44, and This preliminary analysis shows that a shortened picture version of the FCSRT may be useful and applicable for the diagnosis of aMCI without excluding individuals with a low level of schooling

Common variants in Alzheimer’s disease and risk stratification by polygenic risk scores

Genetic discoveries of Alzheimer’s disease are the drivers of our understanding, and together with polygenetic risk stratification can contribute towards planning of feasible and efficient preventive and curative clinical trials. We first perform a large genetic association study by merging all available case-control datasets and by-proxy study results (discovery n = 409,435 and validation size n = 58,190). Here, we add six variants associated with Alzheimer’s disease risk (near APP, CHRNE, PRKD3/NDUFAF7, PLCG2 and two exonic variants in the SHARPIN gene). Assessment of the polygenic risk score and stratifying by APOE reveal a 4 to 5.5 years difference in median age at onset of Alzheimer’s disease patients in APOE ɛ4 carriers. Because of this study, the underlying mechanisms of APP can be studied to refine the amyloid cascade and the polygenic risk score provides a tool to select individuals at high risk of Alzheimer’s disease