Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 149
Filtrar
Más filtros

Bases de datos
Tipo del documento
Intervalo de año de publicación
1.
Genome Res ; 32(4): 778-790, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35210353

RESUMEN

More than 90% of genetic variants are rare in most modern sequencing studies, such as the Alzheimer's Disease Sequencing Project (ADSP) whole-exome sequencing (WES) data. Furthermore, 54% of the rare variants in ADSP WES are singletons. However, both single variant and unit-based tests are limited in their statistical power to detect an association between rare variants and phenotypes. To best use missense rare variants and investigate their biological effect, we examine their association with phenotypes in the context of protein structures. We developed a protein structure-based approach, protein optimized kernel evaluation of missense nucleotides (POKEMON), which evaluates rare missense variants based on their spatial distribution within a protein rather than their allele frequency. The hypothesis behind this test is that the three-dimensional spatial distribution of variants within a protein structure provides functional context to power an association test. POKEMON identified three candidate genes (TREM2, SORL1, and EXOC3L4) and another suggestive gene from the ADSP WES data. For TREM2 and SORL1, two known Alzheimer's disease (AD) genes, the signal from the spatial cluster is stable even if we exclude known AD risk variants, indicating the presence of additional low-frequency risk variants within these genes. EXOC3L4 is a novel AD risk gene that has a cluster of variants primarily shared by case subjects around the Sec6 domain. This cluster is also validated in an independent replication data set and a validation data set with a larger sample size.


Asunto(s)
Enfermedad de Alzheimer , Enfermedad de Alzheimer/genética , Frecuencia de los Genes , Predisposición Genética a la Enfermedad , Humanos , Proteínas Relacionadas con Receptor de LDL/genética , Proteínas Relacionadas con Receptor de LDL/metabolismo , Proteínas de Transporte de Membrana/genética , Mutación Missense , Fenotipo , Secuenciación del Exoma
2.
Int J Sports Med ; 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38599613

RESUMEN

This study assessed the multifaceted relations between measures of workload, psychological state, and recovery throughout an entire soccer season. A prospective longitudinal study was utilized to measure workload (GPS training load, RPE), psychological state (mental stress, mental fatigue, and mood), and recovery (sleep duration, sleep quality, and soreness), across ninety observations. Separate linear-mixed effect models were used to assess outcomes of RPE, soreness, and sleep duration. A linear mixed-effects model explained 59% of the variance in RPE following each session. Specifically, each standard deviation increase in GPS load and mental stress in the morning prior to training increased RPE by 1.46(SE=0.08) and 0.29(SE= 0.07) respectively, following that day's training. Furthermore, a significant interaction was found between several predictor variables and chronological day in the season while predicting RPE. Specifically, for each standard deviation increase in GPS load, RPE went up by 0.055 per day across the season suggesting that load had a higher impact on RPE as the season progressed. In contrast, the interaction of day by mental stress, sleep duration, and soreness continued to be stronger as the season progressed. Each linear mixed-effect model predicted a larger amount of variance when accounting for individual variations in the random effects.

3.
Alzheimers Dement ; 20(1): 253-265, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37578203

RESUMEN

INTRODUCTION: Multiple infectious agents, including viruses, bacteria, fungi, and protozoa, have been linked to Alzheimer's disease (AD) risk by independent lines of evidence. We explored this association by comparing the frequencies of viral species identified in a large sample of AD cases and controls. METHODS: DNA sequence reads that did not align to the human genome in sequences were mapped to viral reference sequences, quantified, and then were tested for association with AD in whole exome sequences (WES) and whole genome sequences (WGS) datasets. RESULTS: Several viruses were significant predictors of AD according to the machine learning classifiers. Subsequent regression analyses showed that herpes simplex type 1 (HSV-1) (odds ratio [OR] = 3.71, p = 8.03 × 10-4) and human papillomavirus 71 (HPV-71; OR = 3.56, p = 0.02), were significantly associated with AD after Bonferroni correction. The phylogenetic-related cluster of Herpesviridae was significantly associated with AD in several strata of the data (p < 0.01). DISCUSSION: Our results support the hypothesis that viral infection, especially HSV-1, is associated with AD risk.


Asunto(s)
Enfermedad de Alzheimer , Herpes Simple , Herpesvirus Humano 1 , Humanos , Enfermedad de Alzheimer/complicaciones , Filogenia , Herpesvirus Humano 1/genética , ADN
4.
Clin Infect Dis ; 76(2): 229-237, 2023 01 13.
Artículo en Inglés | MEDLINE | ID: mdl-36173830

RESUMEN

BACKGROUND: Carbapenem-resistant Klebsiella pneumoniae (CRKp) is the most prevalent carbapenem-resistant Enterobacterales in the United States. We evaluated CRKp clustering in patients in US hospitals. METHODS: From April 2016 to August 2017, 350 patients with clonal group 258 CRKp were enrolled in the Consortium on Resistance Against Carbapenems in Klebsiella and other Enterobacteriaceae, a prospective, multicenter, cohort study. A maximum likelihood tree was constructed using RAxML. Static clusters shared ≤21 single-nucleotide polymorphisms (SNP) and a most recent common ancestor. Dynamic clusters incorporated SNP distance, culture timing, and rates of SNP accumulation and transmission using the R program TransCluster. RESULTS: Most patients were admitted from home (n = 150, 43%) or long-term care facilities (n = 115, 33%). Urine (n = 149, 43%) was the most common isolation site. Overall, 55 static and 47 dynamics clusters were identified involving 210 of 350 (60%) and 194 of 350 (55%) patients, respectively. Approximately half of static clusters were identical to dynamic clusters. Static clusters consisted of 33 (60%) intrasystem and 22 (40%) intersystem clusters. Dynamic clusters consisted of 32 (68%) intrasystem and 15 (32%) intersystem clusters and had fewer SNP differences than static clusters (8 vs 9; P = .045; 95% confidence interval [CI]: -4 to 0). Dynamic intersystem clusters contained more patients than dynamic intrasystem clusters (median [interquartile range], 4 [2, 7] vs 2 [2, 2]; P = .007; 95% CI: -3 to 0). CONCLUSIONS: Widespread intrasystem and intersystem transmission of CRKp was identified in hospitalized US patients. Use of different methods for assessing genetic similarity resulted in only minor differences in interpretation.


Asunto(s)
Enterobacteriaceae Resistentes a los Carbapenémicos , Infecciones por Klebsiella , Humanos , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Klebsiella pneumoniae/genética , Estudios de Cohortes , Estudios Prospectivos , Infecciones por Klebsiella/epidemiología , Infecciones por Klebsiella/tratamiento farmacológico , Carbapenémicos/farmacología , Enterobacteriaceae Resistentes a los Carbapenémicos/genética , Hospitales , Farmacorresistencia Bacteriana
5.
Br J Cancer ; 129(2): 301-308, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37225894

RESUMEN

BACKGROUND: Diagnosis and management of cancers of unknown primary (CUP) remain challenging. This study examines the referral patterns, management and outcomes of patients referred to Australia's first dedicated CUP clinic. METHODS: Retrospective medical record review was conducted for patients seen at the Peter MacCallum Cancer Centre CUP clinic between July 2014 and August 2020. Overall survival (OS) was analysed for patients with a CUP diagnosis where treatment information was available. RESULTS: Of 361 patients referred, fewer than half had completed diagnostic work-up at the time of referral. A diagnosis of CUP was established in 137 (38%), malignancy other than CUP in 177 (49%) and benign pathology in 36 (10%) patients. Genomic testing was successfully completed in 62% of patients with initial provisional CUP and impacted management in 32% by identifying a tissue of origin or actionable genomic alteration. The use of site-specific, targeted therapy or immunotherapy was independently associated with longer OS compared to empirical chemotherapy. CONCLUSION: Our specialised CUP clinic facilitated diagnostic work-up among patients with suspected malignancy and provided access to genomic testing and clinical trials for patients with a CUP diagnosis, all of which are important to improve outcomes in this patient population.


Asunto(s)
Neoplasias Primarias Desconocidas , Humanos , Neoplasias Primarias Desconocidas/diagnóstico , Neoplasias Primarias Desconocidas/genética , Neoplasias Primarias Desconocidas/terapia , Estudios Retrospectivos , Genómica , Perfilación de la Expresión Génica , Australia/epidemiología
6.
Alzheimers Dement ; 19(12): 5550-5562, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37260021

RESUMEN

INTRODUCTION: Most Alzheimer's disease (AD) loci have been discovered in individuals with European ancestry (EA). METHODS: We applied principal component analysis using Gaussian mixture models and an Ashkenazi Jewish (AJ) reference genome-wide association study (GWAS) data set to identify Ashkenazi Jews ascertained in GWAS (n = 42,682), whole genome sequencing (WGS, n = 16,815), and whole exome sequencing (WES, n = 20,504) data sets. The association of AD was tested genome wide (GW) in the GWAS and WGS data sets and exome wide (EW) in all three data sets (EW). Gene-based analyses were performed using aggregated rare variants. RESULTS: In addition to apolipoprotein E (APOE), GW analyses (1355 cases and 1661 controls) revealed associations with TREM2 R47H (p = 9.66 × 10-9 ), rs541586606 near RAB3B (p = 5.01 × 10-8 ), and rs760573036 between SPOCK3 and ANXA10 (p = 6.32 × 10-8 ). In EW analyses (1504 cases and 2047 controls), study-wide significant association was observed with rs1003710 near SMAP2 (p = 1.91 × 10-7 ). A significant gene-based association was identified with GIPR (p = 7.34 × 10-7 ). DISCUSSION: Our results highlight the efficacy of founder populations for AD genetic studies.


Asunto(s)
Enfermedad de Alzheimer , Estudio de Asociación del Genoma Completo , Humanos , Judíos/genética , Predisposición Genética a la Enfermedad/genética , Enfermedad de Alzheimer/genética , Etnicidad , Polimorfismo de Nucleótido Simple/genética
7.
J Fish Biol ; 103(3): 574-592, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37249445

RESUMEN

We evaluated a wetland habitat modification strategy to contrast fish assemblage structure and the production of young-of-the-year (YOY) fish between different engineered habitats (i.e., spawning pool complexes and connectivity channels) relative to unmodified lateral channels in a large drowned river mouth tributary of the St Lawrence River. Prior to habitat modifications, the coastal wetland was impaired by water level regulations and dominance of the invasive hybrid cattail, Typha × glauca, which collectively replaced or created barriers to seasonally flooded spawning habitats important to fish. Connectivity enhancements provided fish access along a wetland habitat gradient from sedge-meadows to the deeper water robust emergent main channel. Across an 8-year fish emigration dataset (2012, 2013, 2016-2021) more than 90% of all captured fish (Ntotal = 218,086 fish) were YOY and modified habitats outperformed the unmodified channels in total fish catch-per-unit-effort (CPUE) per year (both YOY and non-YOY). Spawning pool complexes had higher YOY species richness than unmodified channel habitats. Fish assemblage structure differed between the modified habitats, where connectivity channels and unmodified channels shared a more similar fish assemblage than spawning pool complexes. Modified habitats, however, supported warmer water and higher dissolved oxygen than the unmodified channels. Redundancy analysis and linear mixed-effect modelling with abiotic variables (hydrology, temperature and dissolved oxygen) showed significant effects on fish assemblage structure, species richness and CPUE of fish emigrating from the modified and unmodified habitats. Historic flooding in 2017 and 2019 was a primary driver of YOY fish production and fish assemblage structure, but also appeared to be associated with near anoxic conditions systemwide. YOY fish for several species was inversely affected by floods at spawning pool complexes, but CPUE of YOY fish for these species appeared unaffected at the connectivity channels despite low dissolved oxygen. Diversified habitat structure (i.e., connectivity channels and spawning pool complexes) offers a management option to enhance habitat for fish that allowed compensatory effects on the capture of YOY fish of several species during floods. This multifaceted outcome from the habitat modifications resulted in unique fish assemblages between the channelized and spawning pool habitat. A connectivity-based habitat enhancement strategy provides adaptability for an uncertain climatic and regulatory future for the Laurentian Great Lakes and St Lawrence River.


Asunto(s)
Typhaceae , Humedales , Animales , Agua , Ecosistema , Peces , Ríos , Reproducción
8.
J Strength Cond Res ; 37(3): 733-744, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-35852374

RESUMEN

ABSTRACT: Hurd, KA, Surges, MP, and Farrell, JW. Use of exercise training to enhance the power-duration curve: a systematic review. J Strength Cond Res 37(3): 733-744, 2023-The power/velocity-duration curve consists of critical power (CP), the highest work rate at which a metabolic steady state can obtained, and W' (e.g., W prime), the finite amount of work that can be performed above CP. Significant associations between CP and performance during endurance sports have been reported resulting in CP becoming a primary outcome for enhancement following exercise training interventions. This review evaluated and summarized the effects of different exercise training methodologies for enhancing CP and respective analogs. A systematic review was conducted with the assistance of a university librarian and in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Ten studies met the criteria for inclusion and were reviewed. Four, 2, 2, 1, and 1 articles included swimming, cycling, resistance training, rowing, and running, respectively. Improvements in CP, and respective analogs, were reported in 3 swimming, 2 cycling, and 1 rowing intervention. In addition, only 2 cycling and 1 swimming intervention used CP, and respective analogs, as an index of intensity for prescribing exercise training, with one cycling and one swimming intervention reporting significant improvements in CP. Multiple exercise training modalities can be used to enhance the power/velocity-duration curve. Significant improvements in CP were often reported with no observed improvements in W' or with slight decreases. Training may need to be periodized in a manner that targets enhancements in either CP or W' but not simultaneously.


Asunto(s)
Resistencia Física , Carrera , Humanos , Consumo de Oxígeno , Prueba de Esfuerzo/métodos , Natación
9.
Mult Scler ; 28(1): 29-48, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-33870797

RESUMEN

BACKGROUND: Immune-mediated demyelination and consequent degeneration of oligodendrocytes and axons are hallmark features of multiple sclerosis (MS). Remyelination declines in progressive MS, causing permanent axonal loss and irreversible disabilities. Strategies aimed at enhancing remyelination are critical to attenuate disease progression. OBJECTIVE: We systematically reviewed recent advances in neuroprotective and regenerative therapies for MS, covering preclinical and clinical studies. METHODS: We searched three biomedical databases using defined keywords. Two authors independently reviewed articles for inclusion based on pre-specified criteria. The data were extracted from each study and assessed for risk of bias. RESULTS: Our search identified 7351 studies from 2014 to 2020, of which 221 met the defined criteria. These studies reported 262 interventions, wherein 92% were evaluated in animal models. These interventions comprised protein, RNA, lipid and cellular biologics, small molecules, inorganic compounds, and dietary and physiological interventions. Small molecules were the most highly represented strategy, followed by antibody therapies and stem cell transplantation. CONCLUSION: While significant strides have been made to develop regenerative treatments for MS, the current evidence illustrates a skewed representation of the types of strategies that advance to clinical trials. Further examination is thus required to address current barriers to implementing experimental treatments in clinical settings.


Asunto(s)
Esclerosis Múltiple , Remielinización , Animales , Axones , Esclerosis Múltiple/terapia , Vaina de Mielina , Regeneración Nerviosa , Oligodendroglía
10.
Alzheimers Dement ; 18(2): 294-306, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34152079

RESUMEN

INTRODUCTION: Findings regarding the association between mitochondrial DNA (mtDNA) variants and Alzheimer's disease (AD) are inconsistent. METHODS: We developed a pipeline for accurate assembly and variant calling in mitochondrial genomes embedded within whole exome sequences (WES) from 10,831 participants from the Alzheimer's Disease Sequencing Project (ADSP). Association of AD risk was evaluated with each mtDNA variant and variants located in 1158 nuclear genes related to mitochondrial function using the SCORE test. Gene-based tests were performed using SKAT-O. RESULTS: Analysis of 4220 mtDNA variants revealed study-wide significant association of AD with a rare MT-ND4L variant (rs28709356 C>T; minor allele frequency = 0.002; P = 7.3 × 10-5 ) as well as with MT-ND4L in a gene-based test (P = 6.71 × 10-5 ). Significant association was also observed with a MT-related nuclear gene, TAMM41, in a gene-based test (P = 2.7 × 10-5 ). The expression of TAMM41 was lower in AD cases than controls (P = .00046) or mild cognitive impairment cases (P = .03). DISCUSSION: Significant findings in MT-ND4L and TAMM41 provide evidence for a role of mitochondria in AD.


Asunto(s)
Enfermedad de Alzheimer , Proteínas Mitocondriales , NADH Deshidrogenasa , Enfermedad de Alzheimer/genética , ADN Mitocondrial/genética , Frecuencia de los Genes , Humanos , Mitocondrias/genética , Proteínas Mitocondriales/genética , NADH Deshidrogenasa/genética , Secuenciación del Exoma
11.
Allergy ; 76(10): 2952-2964, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-33811358

RESUMEN

Older adults, especially men and/or those with diabetes, hypertension, and/or obesity, are prone to severe COVID-19. In some countries, older adults, particularly those residing in nursing homes, have been prioritized to receive COVID-19 vaccines due to high risk of death. In very rare instances, the COVID-19 vaccines can induce anaphylaxis, and the management of anaphylaxis in older people should be considered carefully. An ARIA-EAACI-EuGMS (Allergic Rhinitis and its Impact on Asthma, European Academy of Allergy and Clinical Immunology, and European Geriatric Medicine Society) Working Group has proposed some recommendations for older adults receiving the COVID-19 vaccines. Anaphylaxis to COVID-19 vaccines is extremely rare (from 1 per 100,000 to 5 per million injections). Symptoms are similar in younger and older adults but they tend to be more severe in the older patients. Adrenaline is the mainstay treatment and should be readily available. A flowchart is proposed to manage anaphylaxis in the older patients.


Asunto(s)
Anafilaxia , COVID-19 , Anciano , Anafilaxia/etiología , Anafilaxia/prevención & control , Vacunas contra la COVID-19 , Epinefrina , Humanos , Masculino , SARS-CoV-2
12.
Mol Psychiatry ; 25(8): 1859-1875, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-30108311

RESUMEN

The Alzheimer's Disease Sequencing Project (ADSP) undertook whole exome sequencing in 5,740 late-onset Alzheimer disease (AD) cases and 5,096 cognitively normal controls primarily of European ancestry (EA), among whom 218 cases and 177 controls were Caribbean Hispanic (CH). An age-, sex- and APOE based risk score and family history were used to select cases most likely to harbor novel AD risk variants and controls least likely to develop AD by age 85 years. We tested ~1.5 million single nucleotide variants (SNVs) and 50,000 insertion-deletion polymorphisms (indels) for association to AD, using multiple models considering individual variants as well as gene-based tests aggregating rare, predicted functional, and loss of function variants. Sixteen single variants and 19 genes that met criteria for significant or suggestive associations after multiple-testing correction were evaluated for replication in four independent samples; three with whole exome sequencing (2,778 cases, 7,262 controls) and one with genome-wide genotyping imputed to the Haplotype Reference Consortium panel (9,343 cases, 11,527 controls). The top findings in the discovery sample were also followed-up in the ADSP whole-genome sequenced family-based dataset (197 members of 42 EA families and 501 members of 157 CH families). We identified novel and predicted functional genetic variants in genes previously associated with AD. We also detected associations in three novel genes: IGHG3 (p = 9.8 × 10-7), an immunoglobulin gene whose antibodies interact with ß-amyloid, a long non-coding RNA AC099552.4 (p = 1.2 × 10-7), and a zinc-finger protein ZNF655 (gene-based p = 5.0 × 10-6). The latter two suggest an important role for transcriptional regulation in AD pathogenesis.


Asunto(s)
Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/inmunología , Secuenciación del Exoma , Regulación de la Expresión Génica/genética , Inmunidad/genética , Transcripción Genética/genética , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/patología , Péptidos beta-Amiloides/inmunología , Apolipoproteínas E/genética , Femenino , Haplotipos/genética , Humanos , Inmunoglobulina G , Factores de Transcripción de Tipo Kruppel/genética , Masculino , Polimorfismo Genético/genética , ARN Largo no Codificante/genética
14.
J Strength Cond Res ; 35(10): 2862-2869, 2021 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-31306392

RESUMEN

ABSTRACT: Farrell III, JW, Dunn, A, Cantrell, GS, Lantis, DJ, Larson, DJ, and Larson, RD. Effects of group running on the training intensity distribution of collegiate cross-country runners. J Strength Cond Res 35(10): 2862-2869, 2021-Collegiate cross-country training is often conducted and prescribed in a group setting. This may result in the application of an inappropriate training stimulus to athletes due to potentially different physiological responses to the same training prescription. The aim of this investigation was to quantify the training intensity distribution (TID) of a collegiate cross-country team and the associated physiological adaptions. Sixteen subjects, 8 male subjects and 8 female subjects, performed a graded exercise test before and after observational period to determine peak oxygen consumption (V̇o2peak), the speed (S@), heart rate (HR@), and oxygen consumption (V̇o2@) associated with 2 and 4 mmol·L-1 of blood lactate. Training intensity distribution was quantified by assessing time spent in 3 intensity zones calculated as zone 1 (low intensity, HR values HR@2 and HR@4). No statistical differences were observed between male subjects and female subjects for percent of training time spent in zones 1, 2, and 3. No significant interactions were observed between sex and time for performance variables. Male subjects and female subjects improved V̇o2peak, S@4, and V̇o2@4 with male subjects also increasing V̇o2@2. No significant differences were observed between male subjects and female subjects when comparing percent changes for variables. Examining individual data showed that 2 female subjects experienced performance decrements and trained proportionally more in zones 2 and 3 compared with the overall group. The TID and performance decrements of the 2 highlighted subjects suggest that conducting training in a group setting may potentially be detrimental for some collegiate runners.


Asunto(s)
Resistencia Física , Carrera , Atletas , Prueba de Esfuerzo , Femenino , Frecuencia Cardíaca , Humanos , Masculino , Consumo de Oxígeno
15.
Bioinformatics ; 35(17): 3046-3054, 2019 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-30624692

RESUMEN

MOTIVATION: Over the last decade, more diverse populations have been included in genome-wide association studies. If a genetic variant has a varying effect on a phenotype in different populations, genome-wide association studies applied to a dataset as a whole may not pinpoint such differences. It is especially important to be able to identify population-specific effects of genetic variants in studies that would eventually lead to development of diagnostic tests or drug discovery. RESULTS: In this paper, we propose PopCluster: an algorithm to automatically discover subsets of individuals in which the genetic effects of a variant are statistically different. PopCluster provides a simple framework to directly analyze genotype data without prior knowledge of subjects' ethnicities. PopCluster combines logistic regression modeling, principal component analysis, hierarchical clustering and a recursive bottom-up tree parsing procedure. The evaluation of PopCluster suggests that the algorithm has a stable low false positive rate (∼4%) and high true positive rate (>80%) in simulations with large differences in allele frequencies between cases and controls. Application of PopCluster to data from genetic studies of longevity discovers ethnicity-dependent heterogeneity in the association of rs3764814 (USP42) with the phenotype. AVAILABILITY AND IMPLEMENTATION: PopCluster was implemented using the R programming language, PLINK and Eigensoft software, and can be found at the following GitHub repository: https://github.com/gurinovich/PopCluster with instructions on its installation and usage. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Asunto(s)
Etnicidad , Estudio de Asociación del Genoma Completo , Algoritmos , Humanos , Lenguajes de Programación , Programas Informáticos , Tioléster Hidrolasas
16.
Allergy ; 75(3): 636-647, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31549414

RESUMEN

BACKGROUND: Abacavir is associated with hypersensitivity reactions in individuals positive for the HLA-B*57:01 allele. The drug binds within the peptide binding groove of HLA-B*57:01 altering peptides displayed on the cell surface. Presentation of these HLA-abacavir-peptide complexes to T-cells is hypothesized to trigger a CD8+ T-cell response underpinning the hypersensitivity. Thus, the aim of this study was to explore the relationship between the structure of abacavir with HLA-B*57:01 binding and the CD8+ T-cell activation. METHODS: Seventeen abacavir analogues were synthesized and cytokine secretion from abacavir/abacavir analogue-responsive CD8+ T-cell clones was measured using IFN-γ ELIspot. In silico docking studies were undertaken to assess the predicted binding poses of the abacavir analogues within the HLA-B*57:01 peptide binding groove. In parallel, the effect of selected abacavir analogues on the repertoire of self-peptides presented by cellular HLA-B*57:01 was characterized using mass spectrometry. RESULTS: Abacavir and ten analogues stimulated CD8+ T-cell IFN-γ release. Molecular docking of analogues that retained antiviral activity demonstrated a relationship between predicted HLA-B*57:01 binding orientations and the ability to induce a T-cell response. Analogues that stimulated T-cells displayed a perturbation of the natural peptides displayed by HLA-B*57:01. The antigen-specific CD8+ T-cell response was dependent on the enantiomeric form of abacavir at both cyclopropyl and cyclopentyl regions. CONCLUSION: Alteration of the chemical constitution of abacavir generates analogues that retain a degree of pharmacological activity, but have variable ability to activate T-cells. Modelling and immunopeptidome analysis delineate how drug HLA-B*57:01 binding and peptide display by antigen presenting cells relate to the activation of CD8+ T-cells.


Asunto(s)
Linfocitos T CD8-positivos , Hipersensibilidad a las Drogas , Didesoxinucleósidos , Antígenos HLA-B/genética , Humanos , Simulación del Acoplamiento Molecular , Relación Estructura-Actividad
17.
Emerg Infect Dis ; 25(8): 1445-1451, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31310217

RESUMEN

In the United States, fatal transfusion-transmitted infections from red blood cell units are rare. Although this pattern mostly reflects how inhospitable refrigerated red blood cell units are to contaminant growth, fatalities caused by microorganisms that can grow at storage temperature (4°C), but not in standard clinical blood cultures at 37°C, are probably underestimated. We analyzed a fatal red blood cell transfusion in Peoria, Illinois, USA, that occurred in 2017. Samples from the patient's whole blood and the red blood cell unit remained culture-negative during the investigation, despite direct visualization of gram-negative bacilli within the unit immediately after transfusion. We identified the bacteria as Pseudomonas poae, a nonpathogenic pseudomonad carrying multiple cold-shock domain protein genes, and confirmed its cold tolerance and inability to grow at 37°C. Our work indicates transfusion reaction workups need to include testing for psychrophilic organisms, which could explain the cause of other apparently culture-negative transfusion reactions.


Asunto(s)
Transfusión Sanguínea , Infecciones por Pseudomonas/diagnóstico , Infecciones por Pseudomonas/etiología , Pseudomonas , Sepsis/diagnóstico , Sepsis/etiología , Reacción a la Transfusión/diagnóstico , Transfusión de Eritrocitos/efectos adversos , Resultado Fatal , Femenino , Humanos , Illinois/epidemiología , Persona de Mediana Edad , Tipificación de Secuencias Multilocus , Filogenia , Pseudomonas/clasificación , Pseudomonas/genética , Pseudomonas/aislamiento & purificación , Infecciones por Pseudomonas/epidemiología , Infecciones por Pseudomonas/transmisión , ARN Ribosómico 16S/genética , Sepsis/epidemiología , Sepsis/transmisión , Reacción a la Transfusión/epidemiología
18.
Chem Res Toxicol ; 32(10): 2095-2106, 2019 10 21.
Artículo en Inglés | MEDLINE | ID: mdl-31468968

RESUMEN

Hypersensitivity reactions occur frequently in patients upon treatment with sulfamethoxazole (SMX). These adverse effects have been attributed to nitroso sulfamethoxazole (SMX-NO), the reactive product formed from auto-oxidation of the metabolite SMX hydroxylamine. The ability of SMX-NO to prime naïve T-cells in vitro and also activate T-cells derived from hypersensitive patients has illustrated that T-cell activation may occur through the binding of SMX-NO to proteins or through the direct modification of MHC-bound peptides. SMX-NO has been shown to modify cysteine residues in glutathione, designer peptides, and proteins in vitro; however, the presence of these adducts have not yet been characterized in vivo. In this study a parallel in vitro and in vivo analysis of SMX-NO adducts was conducted using mass spectrometry. In addition to the known cysteine adducts, multiple SMX-NO-derived haptenic structures were found on lysine and tyrosine residues of human serum albumin (HSA) in vitro. On lysine residues two haptenic structures were identified including an arylazoalkane adduct and a Schiff base adduct. Interestingly, these adducts are labile to heat and susceptible to hydrolysis as shown by the presence of allysine. Furthermore, SMX-modified HSA adducts were detected in patients on long-term SMX therapy illustrated by the presence of an arylazoalkane adduct derived from a proposed carboxylic acid metabolite of SMX-NO. The presence of these adducts could provide an explanation for the immunogenicity of SMX and the strong responses to SMX-NO observed in T-cell culture assays. Also, the degradation of these adducts to allysine could lead to a stress-related innate immune response required for T-cell activation.


Asunto(s)
Haptenos/inmunología , Compuestos Nitrosos/química , Sulfametoxazol/química , Linfocitos T/efectos de los fármacos , Linfocitos T/inmunología , Células Cultivadas , Estudios de Cohortes , Haptenos/química , Humanos , Espectrometría de Masas , Modelos Moleculares , Estructura Molecular , Compuestos Nitrosos/inmunología , Albúmina Sérica Humana/química , Albúmina Sérica Humana/aislamiento & purificación , Sulfametoxazol/inmunología
19.
J Fish Dis ; 42(7): 1023-1033, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31025373

RESUMEN

Eleven viral haemorrhagic septicaemia virus (VHSV) genotype IVb isolates were sequenced, and their genetic variation explored to determine the source of a VHS outbreak on the eastern shore of Cayuga Lake. An active fish kill of round gobies (Neogobius melanostomus, Pallas) was intensively sampled at King Ferry, NY and nearby Long Point State Park in May 2017. Gross lesions observed on 67 moribund round gobies and two rock bass (Ambloplites rupestris, Rafinesque) included moderately haemorrhagic internal organs and erythematous areas on the head, flank, and fins. RT-qPCR tests for VHSV were positive for all 69 fish. Viral isolation on epithelioma papulosum cyprinid cells showed cytopathic effect characteristic of VHSV for six round goby samples from King Ferry. The complete nucleotide sequence of the VHSV IVb genomes of five Cayuga Lake round goby isolates were derived on an Illumina platform along with 2017 VHSV IVb isolates from round gobies collected from the following: Lake Erie near Dunkirk, NY; the St. Lawrence River near Clayton and Cape Vincent, NY; and Lake St. Lawrence near Massena, NY. The phylogenetic tree created from these aligned sequences and four other complete VHSV IVb genomes shows Cayuga Lake isolates are closely related to the Lake Erie isolates.


Asunto(s)
Brotes de Enfermedades/veterinaria , Enfermedades de los Peces/virología , Peces/virología , Septicemia Hemorrágica Viral/epidemiología , Novirhabdovirus/genética , Animales , Encéfalo/virología , Femenino , Enfermedades de los Peces/epidemiología , Variación Genética , Genoma Viral , Genotipo , Lagos/virología , Masculino , New York/epidemiología , Novirhabdovirus/aislamiento & purificación , Filogenia , Reacción en Cadena en Tiempo Real de la Polimerasa , Análisis de Secuencia de ADN
20.
J Am Pharm Assoc (2003) ; 59(1): 79-86.e1, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30446423

RESUMEN

OBJECTIVES: To describe the Pharmacy Communication Partnership (PROMPT) program's approach to improving medication management for patients during transitions from hospital to the community. SETTING: Two general internal medicine units within a multisite academic hospital in Canada. PRACTICE INNOVATION: Designed by an interprofessional working group, PROMPT uses evidence-informed approaches to facilitate communication between pharmacists in different settings: faxing of the discharge prescription and medical discharge summary to a patient's community pharmacy, followed by a telephone call to the community pharmacist. EVALUATION: A multimethod cross-sectional study used telephone surveys and retrospective chart reviews to describe: 1) the characteristics of patients that hospital pharmacists thought would benefit from PROMPT and the community pharmacies that served them; 2) the number and nature of communication attempts made by community and hospital pharmacists; and 3) community pharmacists' views about PROMPT's potential impact on continuity of care and potential program enhancements. RESULTS: A convenience sample of 100 patients (median age 77 years, interquartile range 66 to 83) who received care from 86 pharmacies were used to evaluate the program. The majority of community pharmacists participating in the surveys considered the intervention to be helpful. Of the 53.7% (n = 44/82) community pharmacists who received discharge summaries, 93.2% (n = 41/44) found the summaries to be useful. Themes arising from community pharmacists' comments were categorized into 3 topics: 1) the benefits of PROMPT; 2) topics of discussion and clarification during telephone calls with hospital pharmacists; and 3) future program improvements. CONCLUSION: Community pharmacists described PROMPT as a time-efficient and helpful bridge linking community pharmacy to hospital inpatient care. Opportunities for future research include determining the characteristics of patients who may benefit most from PROMPT, determining the optimal components of discharge information needed by community pharmacists to enhance medication management, and evaluating whether follow-up telephone calls from the hospital to community pharmacists are necessary for all patients.


Asunto(s)
Comunicación , Continuidad de la Atención al Paciente , Pacientes Internos , Conciliación de Medicamentos/métodos , Farmacéuticos/psicología , Relaciones Profesional-Paciente , Adulto , Anciano , Anciano de 80 o más Años , Actitud del Personal de Salud , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Desarrollo de Programa , Evaluación de Programas y Proyectos de Salud/estadística & datos numéricos , Estudios Retrospectivos , Adulto Joven
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA