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1.
Reprod Biol Endocrinol ; 21(1): 100, 2023 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-37891659

RESUMEN

RESEARCH QUESTION: Are live birth rates affected in frozen embryo transfer cycles that develop transient endometrial cavity fluid that resolves by day of embryo transfer? DESIGN: The first frozen blastocyst transfer cycle between January 1st, 2016 and December 31st, 2019 were included in this retrospective cohort study at an academic fertility center. The presence or absence of endometrial cavity fluid (ECF) detected on initial ultrasound and at time of transfer was recorded. Patients who had persistent ECF at time of transfer were excluded from the study. The primary outcome was live birth rate in the group with resolved ECF relative to the group without ECF. RESULTS: A total of 1034 frozen blastocyst transfer cycles were included, 54 with resolved ECF and 980 without ECF. Adjusted analyses were performed using a log-binomial regression model. Live birth rates were 35.2% and 34.2%, adjusted risk ratio 1.00 [95% CI 0.70-1.50] in the two groups, respectively. CONCLUSION: Live birth rates in frozen embryo transfer cycles are equivalent between patients with resolved endometrial cavity fluid compared to those who never had endometrial cavity fluid. Our findings suggest that the presence of endometrial cavity fluid is likely not detrimental to live birth rates if the fluid spontaneously resolves by the time of embryo transfer.


Asunto(s)
Tasa de Natalidad , Transferencia de Embrión , Embarazo , Femenino , Humanos , Índice de Embarazo , Estudios Retrospectivos , Nacimiento Vivo , Criopreservación
2.
J Med Internet Res ; 24(12): e40035, 2022 12 27.
Artículo en Inglés | MEDLINE | ID: mdl-36322788

RESUMEN

BACKGROUND: COVID-19 data have been generated across the United Kingdom as a by-product of clinical care and public health provision, as well as numerous bespoke and repurposed research endeavors. Analysis of these data has underpinned the United Kingdom's response to the pandemic, and informed public health policies and clinical guidelines. However, these data are held by different organizations, and this fragmented landscape has presented challenges for public health agencies and researchers as they struggle to find relevant data to access and interrogate the data they need to inform the pandemic response at pace. OBJECTIVE: We aimed to transform UK COVID-19 diagnostic data sets to be findable, accessible, interoperable, and reusable (FAIR). METHODS: A federated infrastructure model (COVID - Curated and Open Analysis and Research Platform [CO-CONNECT]) was rapidly built to enable the automated and reproducible mapping of health data partners' pseudonymized data to the Observational Medical Outcomes Partnership Common Data Model without the need for any data to leave the data controllers' secure environments, and to support federated cohort discovery queries and meta-analysis. RESULTS: A total of 56 data sets from 19 organizations are being connected to the federated network. The data include research cohorts and COVID-19 data collected through routine health care provision linked to longitudinal health care records and demographics. The infrastructure is live, supporting aggregate-level querying of data across the United Kingdom. CONCLUSIONS: CO-CONNECT was developed by a multidisciplinary team. It enables rapid COVID-19 data discovery and instantaneous meta-analysis across data sources, and it is researching streamlined data extraction for use in a Trusted Research Environment for research and public health analysis. CO-CONNECT has the potential to make UK health data more interconnected and better able to answer national-level research questions while maintaining patient confidentiality and local governance procedures.


Asunto(s)
COVID-19 , Humanos , COVID-19/epidemiología , Pandemias , Reino Unido/epidemiología
3.
Death Stud ; 46(4): 791-802, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-31829110

RESUMEN

Children who experience a parent's suicide are vulnerable to an increased risk for mental health disorders and suicide attempts. In this study, 17 adults, each a child survivor of their parent's suicide, shared their perceptions of support following the suicide. Helpful experiences included opening communication about suicide and offering individualized support. Unhelpful experiences included judgment and blame, silence regarding suicide, and a heightened awareness of the surviving parent's challenges. Individuals most helpful in meeting the child's needs included those with preexisting relationships. In particular, our findings emphasize the critical need for honest, open, and age-appropriate communication about the parent's suicide.


Asunto(s)
Familia , Sobrevivientes , Adulto , Niño , Comunicación , Familia/psicología , Humanos , Padres/psicología
4.
Org Biomol Chem ; 19(4): 775-784, 2021 01 28.
Artículo en Inglés | MEDLINE | ID: mdl-33439179

RESUMEN

Herein we report the development of a new periodate-based reactive assay system for the fluorescent detection of the cis-diol metabolites produced by Rieske dioxygenases. This sensitive and diastereoselective assay system successfully evaluates the substrate scope of Rieske dioxygenases and determines the relative activity of a rationally designed Rieske dioxygenase variant library. The high throughput capacity of the assay system enables rapid and efficient substrate scope investigations and screening of large dioxygenase variant libraries.


Asunto(s)
Dioxigenasas/metabolismo , Pruebas de Enzimas/métodos , Glicoles/química , Glicoles/metabolismo , Límite de Detección , Estereoisomerismo , Especificidad por Sustrato
5.
BMC Vet Res ; 17(1): 296, 2021 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-34488762

RESUMEN

BACKGROUND: Canine elbow dysplasia (CED) is a complex developmental skeletal disorder associated with a number of pathological conditions within the cubital joint. Because CED is a heritable disease, it is important to identify and remove the affected animals from breeding. The first objective of this study was to describe the prevalence of medial coronoid process disease (MCPD) without (MCD) or with (FMCP) fragmented medial coronoid process, osteochondrosis (OC) and/or osteochondritis dissecans (OCD), ununited anconeal process (UAP), radio-ulnar incongruence (INC R-U) and humero-ulnar incongruence (INC H-U) in dogs with the use of CT imaging. The second aim was to determine the influence of demographics on the prevalence of investigated pathologies in dogs with clinical evidence of elbow dysplasia. RESULTS: In this retrospective study, CT data records of 169 dogs of different breeds presented to the small animal veterinary clinic from 2012 to 2018 were included. 69.23% of dogs diagnosed with CED were young (≤ 2 years old). The mean age of dogs presented with INC R-U was 1.68 ± 1.82 years, while in dogs without INC R-U the mean age was 2.64 ± 2.59 years. The mean age of dogs with INC H-U was 1.94 ± 2.06 years, while without INC H-U 3.29 ± 2.09 years. Labrador Retrievers, German Shepherd and Bernese Mountain dogs were most frequently presented with CED-associated lameness. In 122 dogs OA of varying severity was found. CONCLUSION: INC H-U, FMCP and MCD were among the most frequently found components of CED found in the present study. OCD and UAP were the least frequently diagnosed. Dogs presented with INC R-U and INC H-U were significantly younger than dogs without these CED components. Boxers, Dog de Bordeaux, American Staffordshire terriers and mixed-breed dogs were diagnosed later in life than the other breeds. OA of varying severity was found in 72.18% of dogs. Males accounted for more than 75% of the study population.


Asunto(s)
Enfermedades de los Perros/diagnóstico por imagen , Miembro Anterior/diagnóstico por imagen , Artropatías/veterinaria , Tomografía Computarizada por Rayos X/veterinaria , Factores de Edad , Animales , Enfermedades de los Perros/epidemiología , Perros , Femenino , Artropatías/diagnóstico por imagen , Artropatías/epidemiología , Masculino , Prevalencia , Estudios Retrospectivos , Especificidad de la Especie
6.
J Arthroplasty ; 36(1): 325-330, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-32771288

RESUMEN

BACKGROUND: Prior registry data suggest that perioperative red blood cell (RBC) transfusion may increase the incidence of venous thromboembolism (VTE) in patients status post surgery. However, there are limited data that explore VTE risk after perioperative transfusion in the setting of primary total joint arthroplasty (TJA). Our aim is to investigate the association between perioperative RBC transfusion and the development of symptomatic VTE after adjusting for confounding variables. METHODS: We retrospectively reviewed all patients undergoing primary TJA at a single institution from 2001 to 2016. The primary outcome was development of symptomatic VTE (deep vein thrombosis or pulmonary embolism) up to 90 days following primary TJA. To identify the association between RBC transfusion and development of VTE, univariate and multivariate analyses were used, as well as a sensitivity analysis using propensity score matching based on patient comorbidities. RESULTS: Of the 29,003 patients who underwent TJA, 2500 (8.62%) received RBC transfusion perioperatively and 302 (1.04%) developed a postoperative VTE within 90 days of surgery. While univariate analysis did suggest a slightly increased incidence of VTE in association with RBC transfusion (odds ratio [OR], 1.53; 95% confidence interval [CI], 1.09-2.16), this difference was eliminated when multivariate analysis (OR, 0.42; 95% CI, 0.12-1.39) and propensity score matching (propensity-matched OR, 1.2; 95% CI, 0.7-1.8) were employed. CONCLUSION: Perioperative RBC transfusion does not significantly increase the incidence of symptomatic VTE following primary TJA in the 90-day postoperative period after adjustment for host VTE risk scores and other confounding variables. Perioperative RBC transfusion may be safely administered if indicated following total hip and knee arthroplasty.


Asunto(s)
Artroplastia de Reemplazo de Cadera , Artroplastia de Reemplazo de Rodilla , Embolia Pulmonar , Tromboembolia Venosa , Artroplastia de Reemplazo de Cadera/efectos adversos , Artroplastia de Reemplazo de Rodilla/efectos adversos , Transfusión de Eritrocitos/efectos adversos , Humanos , Estudios Retrospectivos , Factores de Riesgo , Tromboembolia Venosa/epidemiología , Tromboembolia Venosa/etiología
7.
Death Stud ; 45(10): 795-804, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-31752609

RESUMEN

Children often have difficulty talking openly about a parent's suicide. Bibliotherapy can help, but no bibliotherapy studies address parental suicide. We gave a focus group (5 paraprofessionals) 15 children's books addressing grief, parental suicide, and emotional expression, asking them which books were most helpful. They emphasized individualizing treatment to fit the child, recommending the books that honestly portrayed suicide, showed a way forward, provided hope, and assured children that they are not alone. The most highly recommend books were Bart Speaks Out: Breaking the Silence on Suicide and After a Suicide Death: A Workbook for Grieving Kids.


Asunto(s)
Consejeros , Suicidio , Niño , Comunicación , Humanos , Padres , Percepción
8.
Sensors (Basel) ; 19(9)2019 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-31086036

RESUMEN

Diamond is a good candidate for harsh environment sensing due to its high melting temperature, Young's modulus, and thermal conductivity. A sensor made of diamond will be even more promising when combined with some advantages of optical sensing (i.e., EMI inertness, high temperature operation, and miniaturization). We present a miniature diamond-based fiber optic pressure sensor fabricated using dual polymer-ceramic adhesives. The UV curable polymer and the heat-curing ceramic adhesive are employed for easy and reliable optical fiber mounting. The usage of the two different adhesives considerably improves the manufacturability and linearity of the sensor, while significantly decreasing the error from the temperature cross-sensitivity. Experimental study shows that the sensor exhibits good linearity over a pressure range of 2.0-9.5 psi with a sensitivity of 18.5 nm/psi (R2 = 0.9979). Around 275 °C of working temperature was achieved by using polymer/ceramic dual adhesives. The sensor can benefit many fronts that require miniature, low-cost, and high-accuracy sensors including biomedical and industrial applications. With an added antioxidation layer on the diamond diaphragm, the sensor can also be applied for harsh environment applications due to the high melting temperature and Young's modulus of the material.

9.
J Med Libr Assoc ; 107(4): 472-487, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31607805

RESUMEN

The United States' entry into the First World War prompted progressives to reform veterans' entitlements in the hopes of creating a system insulated from corruption and capable of rehabilitating disabled veterans into productive members of society. The replacement of pensions with medical care for wounded and disabled soldiers through the Reconstruction Hospital System was originally intended as a temporary measure but resulted in establishing the foundations of the modern veterans' health care system. Yet, these reforms would not have been possible without the support from the community of war veterans to which these reforms applied. By examining the communal values expressed in publications produced by and for soldiers, this paper explores the ways in which the Great War's veteran community expressed agency in the process of reforming the US veteran entitlements.


Asunto(s)
Personas con Discapacidad/historia , Medicina Militar/historia , Personal Militar/historia , Veteranos/historia , Primera Guerra Mundial , Historia del Siglo XX , Humanos , Estados Unidos , United States Department of Veterans Affairs/historia
10.
J Adolesc ; 69: 1-10, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30199834

RESUMEN

INTRODUCTION: The pervasive and derogatory use of homophobic language is a threat to safe, respectful, and inclusive school environments. Group membership has been shown to influence how students use homophobic language. Previous qualitative studies have largely approached the use of this language from the theoretical framework of hegemonic masculinity. In contrast, the current study actively challenged all assumptions about the use of this language. METHOD: This study was conducted in a public high school located in a rural conservative Christian community in the Intermountain West (USA). Using hermeneutic qualitative methodology to assess individual perceptions of homophobic language, 20 randomly selected 12th-grade male students (17-18 years of age) were individually interviewed. RESULTS: Three distinct groups emerged during our interviews: students on the debate team, students who strongly identified with a conservative religion, and students on popular athletic teams. Membership in specific peer groups influenced how students participated in or abstained from using homophobic language. Contrary to the prevailing research that pairs religiosity with negatively biased attitudes toward LGBTQIA, in this study, participants' religious beliefs appeared to be associated with respecting others' feelings and a decreased likelihood of using homophobic language. CONCLUSIONS: After summarizing this study's findings, we conclude with implications for practice. To more effectively deter the use of homophobic language, we encourage school-based interventions that target specific groups of adolescents and consider the social context in which homophobic language occurs.


Asunto(s)
Conducta del Adolescente/psicología , Grupo Paritario , Estudiantes/psicología , Conducta Verbal , Adolescente , Homofobia/psicología , Humanos , Masculino , Percepción , Población Rural , Medio Social
11.
Biochim Biophys Acta ; 1864(8): 1050-60, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26945514

RESUMEN

The flower is the most important biological structure for ensuring angiosperms reproductive success. Not only does the flower contain critical reproductive organs, but the wide variation in morphology, color, and scent has evolved to entice specialized pollinators, and arguably mankind in many cases, to ensure the successful propagation of its species. Recent proteomic approaches have identified protein candidates related to these flower traits, which has shed light on a number of previously unknown mechanisms underlying these traits. This review article provides a comprehensive overview of the latest advances in proteomic research in floral biology according to the order of flower structure, from corolla to male and female reproductive organs. It summarizes mainstream proteomic methods for plant research and recent improvements on two dimensional gel electrophoresis and gel-free workflows for both peptide level and protein level analysis. The recent advances in sequencing technologies provide a new paradigm for the ever-increasing genome and transcriptome information on many organisms. It is now possible to integrate genomic and transcriptomic data with proteomic results for large-scale protein characterization, so that a global understanding of the complex molecular networks in flower biology can be readily achieved. This article is part of a Special Issue entitled: Plant Proteomics--a bridge between fundamental processes and crop production, edited by Dr. Hans-Peter Mock.


Asunto(s)
Flores/metabolismo , Proteínas de Plantas/metabolismo , Plantas/metabolismo , Proteómica/métodos , Carácter Cuantitativo Heredable , Flores/genética , Perfilación de la Expresión Génica , Proteínas de Plantas/genética , Plantas/genética
12.
Mov Disord ; 31(11): 1664-1675, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27620011

RESUMEN

OBJECTIVES: Diffusivity in white-matter tracts is abnormal throughout the brain in cross-sectional studies of prodromal Huntington's disease. To date, longitudinal changes have not been observed. The present study investigated cross-sectional and longitudinal changes in white-matter diffusivity in relationship to the phase of prodromal Huntington's progression, and compared them with changes in brain volumes and clinical variables that track disease progression. METHODS: Diffusion MRI profiles were studied for 2 years in 37 gene-negative controls and 64 prodromal Huntington's disease participants in varied phases of disease progression. To estimate the relative importance of diffusivity metrics in the prodromal phase, group effects were rank ordered relative to those obtained from analyses of brain volumes, motor, cognitive, and sensory variables. RESULTS: First, at baseline diffusivity was abnormal throughout all tracts, especially as individuals approached a manifest Huntington's disease diagnosis. Baseline diffusivity metrics in 6 tracts and basal ganglia volumes best distinguished among the groups. Second, group differences in longitudinal change in diffusivity were localized to the superior fronto-occipital fasciculus, most prominently in individuals closer to a diagnosis. Group differences were also observed in longitudinal changes of most brain volumes, but not clinical variables. Last, increases in motor symptoms across time were associated with greater changes in the superior fronto-occipital fasciculus diffusivity and corpus callosum, cerebrospinal fluid, and lateral ventricle volumes. CONCLUSIONS: These novel findings provide new insights into changes within 2 years in different facets of brain structure and their clinical relevance to changes in symptomatology that is decisive for a manifest Huntington's diagnosis. © 2016 International Parkinson and Movement Disorder Society.


Asunto(s)
Ganglios Basales/diagnóstico por imagen , Progresión de la Enfermedad , Enfermedad de Huntington/diagnóstico por imagen , Enfermedad de Huntington/fisiopatología , Síntomas Prodrómicos , Sustancia Blanca/diagnóstico por imagen , Adulto , Estudios Transversales , Imagen de Difusión por Resonancia Magnética/métodos , Imagen de Difusión Tensora , Femenino , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad
13.
Soft Matter ; 12(4): 1133-44, 2016 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-26575014

RESUMEN

Herein, we examine the synergistic impact of both ion clustering and block copolymer morphology on ion conductivity in two polymerized ionic liquid (PIL) diblock copolymers with similar chemistries but different side alkyl spacer chain lengths (ethyl versus undecyl). When saturated in liquid water, water/ion clusters were observed only in the PIL block copolymer with longer alkyl side chains (undecyl) as evidenced by both small-angle neutron scattering and intermediate-angle X-ray scattering, i.e., water/ion clusters form within the PIL microdomain under these conditions. The resulting bromide ion conductivity in the undecyl sample was higher than the ethyl sample (14.0 mS cm(-1)versus 6.1 mS cm(-1) at 50 °C in liquid water) even though both samples had the same block copolymer morphology (lamellar) and the undecyl sample had a lower ion exchange capacity (0.9 meq g(-1)versus 1.4 meq g(-1)). No water/ion clusters were observed in either sample under high humidity or dry conditions. The resulting ion conductivity in the undecyl sample with lamellar morphology was significantly higher in the liquid water saturated state compared to the high humidity state (14.0 mS cm(-1)versus 4.2 mS cm(-1)), whereas there was no difference in ion conductivity in the ethyl sample when comparing these two states. These results show that small chemical changes to ion-containing block copolymers can induce water/ion clusters within block copolymer microdomains and this can subsequently have a significant effect on ion transport.

14.
Dement Geriatr Cogn Disord ; 42(1-2): 106-16, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27623397

RESUMEN

AIMS: We examined the effect of vascular or Lewy body co-pathologies in subjects with autopsy-confirmed Alzheimer's disease (AD) on the rate of cognitive and functional decline and transition to dementia. METHODS: In an autopsy sample of prospectively characterized subjects from the National Alzheimer's Coordinating Center database, neuropathology diagnosis was used to define the groups of pure AD (pAD, n = 84), mixed vascular and AD (ADV, n = 54), and mixed Lewy body disease and AD (ADLBD, n = 31). Subjects had an initial Clinical Dementia Rating-Global (CDR-G) score <1, Mini-Mental State Examination ≥15, a final visit CDR-G >1, ≥3 evaluations, and Braak tangle stage ≥III. We compared the rate of cognitive and functional decline between the groups. RESULTS: The rate of functional and cognitive decline was lower for ADV, and ADV patients had less severe deficits on CDR-G and the CDR-Sum of Boxes scores at the last visit than pAD and ADLBD patients. No significant differences were noted between ADLBD and pAD patients. After controlling for age at death, the odds of reaching CDR ≥1 at the last visit were lower in the ADV subjects compared to the pAD subjects. CONCLUSIONS: The mean rate of functional and cognitive decline among ADV subjects was slower than among either pAD or ADLBD patients. Vascular pathology did not increase the odds of attaining CDR ≥1 when occurring with AD in this national cohort.


Asunto(s)
Enfermedad de Alzheimer , Disfunción Cognitiva/diagnóstico , Demencia Vascular , Enfermedad por Cuerpos de Lewy , Anciano , Enfermedad de Alzheimer/diagnóstico , Enfermedad de Alzheimer/patología , Enfermedad de Alzheimer/psicología , Autopsia/métodos , Autopsia/estadística & datos numéricos , Estudios de Cohortes , Demencia Vascular/diagnóstico , Demencia Vascular/patología , Demencia Vascular/psicología , Femenino , Humanos , Enfermedad por Cuerpos de Lewy/diagnóstico , Enfermedad por Cuerpos de Lewy/patología , Enfermedad por Cuerpos de Lewy/psicología , Masculino , Pruebas de Estado Mental y Demencia , Estadística como Asunto , Estados Unidos
17.
BMC Genomics ; 16: 622, 2015 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-26289943

RESUMEN

BACKGROUND: Cymbidium ensifolium is one of the most important ornamental flowers in China, with an elegant shape, beautiful appearance, and a fragrant aroma. Its unique flower shape has long attracted scientists. MicroRNAs (miRNAs) are critical regulators in plant development and physiology, including floral development. However, to date, few studies have examined miRNAs in C. ensifolium. RESULTS: In this study, we employed Solexa technology to sequence four small RNA libraries from two flowering phases to identify miRNAs related to floral development. We identified 48 mature conserved miRNA and 71 precursors. These conserved miRNA belonged to 20 families. We also identified 45 novel miRNA which includes 21 putative novel miRNAs*, and 28 hairpin forming precursors. Two trans-acting small interfering RNAs (ta-siRNAs) were identified, one of which was homologous to TAS3a1. TAS3a1 belongs to the TAS3 family, which has been previously reported to target auxin response factors (ARF) and be involved in plant growth and floral development. Moreover, we built a C. ensifolium transctriptome database to identify genes targeted by miRNA, which resulted in 790 transcriptomic target unigenes. The target unigenes were annotated with information from the non-redundant (Nr), gene ontology database (GO), eukaryotic orthologous groups (KOGs) and Kyoto encyclopedia of genes and genomes (KEGG) database. The unigenes included MADS-box transcription factors targeted by miR156, miR172 and miR5179, and various hormone responding factors targeted by miR159. The MADS-box transcription factors are well known to determine the identity of flower organs and hormone responding factors involved in floral development. In expression analysis, three novel and four conserved miRNA were differentially expressed between two phases of flowering. The results were confirmed by RNA-seq and qRT-PCR. The differential expression of two miRNA, miR160 and miR396, targeted ARFs and growth regulating factor (GRF), respectively. However, most of these small RNA were clustered in the uncharacterized group, which suggests there may be many novel small non-coding RNAs yet to be discovered. CONCLUSION: Our study provides a diverse set of miRNAs related to cymbidium floral development and serves as a useful resource for investigating miRNA-mediated regulatory mechanisms of floral development.


Asunto(s)
Flores/crecimiento & desarrollo , Orchidaceae/genética , ARN de Planta/análisis , ARN Pequeño no Traducido/análisis , Flores/genética , Perfilación de la Expresión Génica , Regulación del Desarrollo de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Secuenciación de Nucleótidos de Alto Rendimiento , Anotación de Secuencia Molecular , Orchidaceae/fisiología
18.
Neuroimage ; 111: 136-46, 2015 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-25687593

RESUMEN

Healthy aging is associated with cognitive declines typically accompanied by increased task-related brain activity in comparison to younger counterparts. The Scaffolding Theory of Aging and Cognition (STAC) (Park and Reuter-Lorenz, 2009; Reuter-Lorenz and Park, 2014) posits that compensatory brain processes are responsible for maintaining normal cognitive performance in older adults, despite accumulation of aging-related neural damage. Cross-sectional studies indicate that cognitively intact elders at genetic risk for Alzheimer's disease (AD) demonstrate patterns of increased brain activity compared to low risk elders, suggesting that compensation represents an early response to AD-associated pathology. Whether this compensatory response persists or declines with the onset of cognitive impairment can only be addressed using a longitudinal design. The current prospective, 5-year longitudinal study examined brain activation in APOE ε4 carriers (N=24) and non-carriers (N=21). All participants, ages 65-85 and cognitively intact at study entry, underwent task-activated fMRI, structural MRI, and neuropsychological assessments at baseline, 18, and 57 months. fMRI activation was measured in response to a semantic memory task requiring participants to discriminate famous from non-famous names. Results indicated that the trajectory of change in brain activation while performing this semantic memory task differed between APOE ε4 carriers and non-carriers. The APOE ε4 group exhibited greater activation than the Low Risk group at baseline, but they subsequently showed a progressive decline in activation during the follow-up periods with corresponding emergence of episodic memory loss and hippocampal atrophy. In contrast, the non-carriers demonstrated a gradual increase in activation over the 5-year period. Our results are consistent with the STAC model by demonstrating that compensation varies with the severity of underlying neural damage and can be exhausted with the onset of cognitive symptoms and increased structural brain pathology. Our fMRI results could not be attributed to changes in task performance, group differences in cerebral perfusion, or regional cortical atrophy.


Asunto(s)
Envejecimiento/fisiología , Enfermedad de Alzheimer/fisiopatología , Encéfalo/fisiopatología , Predisposición Genética a la Enfermedad , Memoria a Largo Plazo/fisiología , Anciano , Anciano de 80 o más Años , Envejecimiento/patología , Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/patología , Apolipoproteína E4 , Atrofia/patología , Encéfalo/patología , Femenino , Humanos , Estudios Longitudinales , Imagen por Resonancia Magnética , Masculino
19.
BMC Genet ; 15: 124, 2014 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-25481640

RESUMEN

BACKGROUND: Cymbidium is a genus of 68 species in the orchid family, with extremely high ornamental value. Marker-assisted selection has proven to be an effective strategy in accelerating plant breeding for many plant species. Analysis of cymbidiums genetic background by molecular markers can be of great value in assisting parental selection and breeding strategy design, however, in plants such as cymbidiums limited genomic resources exist. In order to obtain efficient markers, we deep sequenced the C. ensifolium transcriptome to identify simple sequence repeats derived from gene regions (genic-SSR). RESULT: The 7,936 genic-SSR markers were identified. A total of 80 genic-SSRs were selected, and primers were designed according to their flanking sequences. Of the 80 genic-SSR primer sets, 62 were amplified in C. ensifolium successfully, and 55 showed polymorphism when cross-tested among 9 Cymbidium species comprising 59 accessions. Unigenes containing the 62 genic-SSRs were searched against Non-redundant (Nr), Gene Ontology database (GO), eukaryotic orthologous groups (KOGs) and Kyoto Encyclopedia of Genes and Genomes (KEGG) database. The search resulted in 53 matching Nr sequences, of which 39 had GO terms, 18 were assigned to KOGs, and 15 were annotated with KEGG. Genetic diversity and population structure were analyzed based on 55 polymorphic genic-SSR data among 59 accessions. The genetic distance averaged 0.3911, ranging from 0.016 to 0.618. The polymorphic index content (PIC) of 55 polymorphic markers averaged 0.407, ranging from 0.033 to 0.863. A model-based clustering analysis revealed that five genetic groups existed in the collection. Accessions from the same species were typically grouped together; however, C. goeringii accessions did not always form a separate cluster, suggesting that C. goeringii accessions were polyphyletic. CONCLUSION: The genic-SSR identified in this study constitute a set of markers that can be applied across multiple Cymbidium species and used for the evaluation of genetic relationships as well as qualitative and quantitative trait mapping studies. Genic-SSR's coupled with the functional annotations provided by the unigenes will aid in mapping candidate genes of specific function.


Asunto(s)
Orchidaceae/genética , Ontología de Genes , Genes de Plantas , Marcadores Genéticos , Repeticiones de Microsatélite , Anotación de Secuencia Molecular , Filogenia , Polimorfismo Genético , Análisis de Secuencia de ADN
20.
Dement Geriatr Cogn Disord ; 38(3-4): 224-33, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24903099

RESUMEN

BACKGROUND: There is heterogeneity in the pattern of early cognitive deficits in Alzheimer's disease (AD). However, whether the severity of initial cognitive deficits relates to different clinical trajectories of AD progression is unclear. OBJECTIVE: To determine if deficits in specific cognitive domains at the initial visit relate to the rate of progression in clinical trajectories of AD dementia. METHODS: 68 subjects from the National Alzheimer's Coordinating Center database who had autopsy-confirmed AD as the primary diagnosis and at least 3 serial assessments a year apart, with a Mini-Mental State Examination (MMSE) score >15 and a Clinical Dementia Rating Scale-Global (CDR-G) score ≤1 at the initial visit were included. A mixed regression model was used to examine the association between initial neuropsychological performance and rate of change on the MMSE and CDR Sum of Boxes. RESULTS: Preservation of working memory, but not episodic memory, in the mild cognitive impairment and early dementia stages of AD relates to slower rate of functional decline. DISCUSSION: These findings are relevant for estimating the rate of decline in AD clinical trials and in counseling patients and families. Improving working memory performance as a possible avenue to decrease the rate of functional decline in AD dementia warrants closer investigation.


Asunto(s)
Actividades Cotidianas , Enfermedad de Alzheimer/fisiopatología , Memoria a Corto Plazo/fisiología , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/psicología , Autopsia , Bases de Datos Factuales , Progresión de la Enfermedad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , Análisis de Regresión
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