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1.
Cytokine ; 171: 156355, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37690424

RESUMO

Dried blood spots (DBS) collected on filter paper such as Guthrie cards are stored for years at room temperature. The assumption is that once dried, the samples remain stable and quantifiable indefinitely since the metabolites these were initially designed to measure, are known for their extended stability. The concentration of other blood proteins such as cytokines, however, are known to vary with storage even in liquid samples stored at -80 °C for extended periods of time. We sought to determine if cytokines are stable for up to 5 months when stored as a dried blood sample using volumetric absorptive microsampling (VAMS) devices. To test this, blood was collected from 4 healthy participants, spiked with recombinant cytokines, and collected into 30 µL VAMS devices. These prepared VAMS devices were stored at room temperature, 4 °C, or -20 °C for up to 5 months and matching VAMS liquid extracts were stored at -80 °C for the same period of time. At each timepoint, the samples were extracted from the VAMS devices and the extracts were analysed by Luminex® for quantification of up to 31 cytokines. These methods were also tested in a remote clinical study over a period of up to 8 months. Cytokine analysis revealed that room temperature, the current standard for DBS and VAMS storage, performed the poorest out of all storage temperatures with significant losses in 13/21 analytes compared to 4 °C at 5 months. Storage at 4 °C or colder performed well for the majority of analytes tested, however out of those, the optimal storage temperature differed for each analyte. There were a small number of analytes that performed poorly regardless of storage conditions and for fractalkine, this was found to be caused by inefficient recovery during extraction. Cytokine concentrations from finger-prick samples were also found to be much more variable that those in venous blood samples. Our results highlight the need to understand the stability of analytes of interest before committing to longitudinal collection and storage of samples in VAMS devices. These data give confidence that storage at 4 °C or colder was beneficial for cytokine stability. Wherein 25/31 cytokines were quantifiably stable at -20 °C when stored for 3 months and 17/21 were quantifiably stable after 5 months when stored at 4 °C.

2.
Mol Psychiatry ; 21(2): 198-204, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25824298

RESUMO

Gamma-butyric acid (GABA) dysfunction has been implicated in the pathophysiology of schizophrenia and its cognitive deficits. Proton magnetic resonance spectroscopy (MRS) was used to test the hypothesis that older participants with schizophrenia have lower anterior cingulate GABA levels compared with older control participants. One-hundred forty-five participants completed this study. For detection of GABA, spectra were acquired from the medial frontal/anterior cingulate cortex using a macromolecule-suppressed MEGA-PRESS sequence. Patients were evaluated for psychopathology and all participants completed neuropsychological tests of working memory, processing speed and functional capacity. GABA levels were significantly lower in the older participants with schizophrenia (n=31) compared with the older control (n=37) group (P=0.003) but not between the younger control (n=40) and schizophrenia (n=29) groups (P=0.994). Age strongly predicted GABA levels in the schizophrenia group accounting for 42% of the variance, but the effect of age was less in the control group accounting for 5.7% of the variance. GABA levels were specifically related to working memory but not processing speed performance, functional capacity, or positive or negative symptom severity. This is the largest MRS study of GABA in schizophrenia and the first to examine GABA without macromolecule contamination, a potentially significant issue in previous studies. GABA levels more rapidly declined with advancing age in the schizophrenia compared with the control group. Interventions targeted at halting the decline or increasing GABA levels may improve functional outcomes and quality of life as patients with schizophrenia age.


Assuntos
Esquizofrenia/patologia , Ácido gama-Aminobutírico/metabolismo , Ácido gama-Aminobutírico/fisiologia , Adulto , Fatores Etários , Estudos de Casos e Controles , Transtornos Cognitivos/patologia , Feminino , Lobo Frontal/patologia , Giro do Cíngulo/patologia , Humanos , Imageamento por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética/métodos , Masculino , Memória de Curto Prazo/fisiologia , Pessoa de Meia-Idade , Testes Neuropsicológicos , Qualidade de Vida
3.
Psychol Med ; 46(9): 1829-38, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27019009

RESUMO

BACKGROUND: Twin and family studies using Western samples have established that child and adolescent anxiety and depression are under substantial genetic, modest shared environmental, and substantial non-shared environmental influences. Generalizability of these findings to non-Western societies remains largely unknown, particularly regarding the changes of genetic and environmental influences with age. The current study examined changes in genetic and environmental influences on self-reported anxiety and depression from late childhood to mid-adolescence among a Chinese twin sample. Sex differences were also examined. METHOD: Self-reported anxiety and depression were collected from 712 10- to 12-year-old Chinese twins (mean = 10.88 years, 49% males) and again 3 years later. Quantitative genetic modeling was used to examine developmental changes in genetic and environmental influences on anxiety and depression, and sex differences. RESULTS: Heritability of anxiety and depression in late childhood (23 and 20%) decreased to negligible in mid-adolescence, while shared environmental influences increased (20 and 27% to 57 and 60%). Shared environmental factors explained most of the continuity of anxiety and depression (75 and 77%). Non-shared environmental factors were largely time-specific. No sex differences were observed. CONCLUSIONS: Shared environmental influences might be more pronounced during the transition period of adolescence in non-Western societies such as China. Future research should examine similarities and differences in the genetic and environmental etiologies of child and adolescent internalizing and other psychopathology in development between Western and non-Western societies.


Assuntos
Desenvolvimento do Adolescente/fisiologia , Ansiedade , Desenvolvimento Infantil/fisiologia , Depressão , Interação Gene-Ambiente , Adolescente , Ansiedade/epidemiologia , Ansiedade/etiologia , Ansiedade/genética , Criança , China/epidemiologia , Depressão/epidemiologia , Depressão/etiologia , Depressão/genética , Feminino , Humanos , Masculino
4.
Theor Appl Genet ; 128(10): 1917-32, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26093611

RESUMO

KEY MESSAGE: Publically available SNP array increases the marker density for genotyping of forage crop, Lolium perenne. Applied to 90 European ecotypes composed of 716 individuals identifies a significant genetic-geographic correlation. Grassland ecosystems are ubiquitous across temperate and tropical regions, totalling 37% of the terrestrial land cover of the planet, and thus represent a global resource for understanding local adaptations to environment. However, genomic resources for grass species (outside cereals) are relatively poor. The advent of next-generation DNA sequencing and high-density SNP genotyping platforms enables the development of dense marker assays for population genetics analyses and genome-wide association studies. A high-density SNP marker resource (Illumina Infinium assay) for perennial ryegrass (Lolium perenne) was created and validated in a broad ecotype collection of 716 individuals sampled from 90 sites across Europe. Genetic diversity within and between populations was assessed. A strong correlation of geographic origin to genetic structure was found using principal component analysis, with significant correlation to longitude and latitude (P < 0.001). The potential of this array as a resource for studies of germplasm diversity and identifying traits underpinning adaptive variation is highlighted.


Assuntos
Ecótipo , Genética Populacional , Lolium/genética , Polimorfismo de Nucleotídeo Único , DNA de Plantas/genética , Europa (Continente) , Marcadores Genéticos , Genótipo , Técnicas de Genotipagem , Geografia , Análise de Sequência com Séries de Oligonucleotídeos , Análise de Sequência de DNA
5.
J Med Genet ; 51(12): 789-96, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25280751

RESUMO

BACKGROUND AND AIMS: Lynch syndrome (LS) patients have DNA mismatch repair deficiency and up to 80% lifetime risk of colorectal cancer (CRC). Screening of mutation carriers reduces CRC incidence and mortality. Selection for constitutional mutation testing relies on family history (Amsterdam and Bethesda Guidelines) and tumour-derived biomarkers. Initial biomarker analysis uses mismatch repair protein immunohistochemistry and microsatellite instability. Abnormalities in either identify mismatch repair deficiency but do not differentiate sporadic epigenetic defects, due to MLH1 promoter region methylation (13% of CRCs) from LS (4% of CRCs). A diagnostic biomarker capable of making this distinction would be valuable. This study compared two biomarkers in tumours with mismatch repair deficiency; quantification of methylation of the MLH1 promoter region using a novel assay and BRAF c.1799T>A, p.(Val600Glu) mutation status in the identification of constitutional mutations. METHODS: Tumour DNA was extracted (formalin fixed, paraffin embedded, FFPE tissue) and pyrosequencing used to test for MLH1 promoter methylation and presence of the BRAF c.1799T>A, p.(Val600Glu) mutation 71 CRCs from individuals with pathogenic MLH1 mutations and 73 CRCs with sporadic MLH1 loss. Specificity and sensitivity was compared. FINDINGSS: Unmethylated MLH1 promoter: sensitivity 94.4% (95% CI 86.2% to 98.4%), specificity 87.7% (95% CI 77.9% to 94.2%), Wild-type BRAF (codon 600): sensitivity 65.8% (95% CI 53.7% to 76.5%), specificity 98.6% (95% CI 92.4% to 100.0%) for the identification of those with pathogenic MLH1 mutations. CONCLUSIONS: Quantitative MLH1 promoter region methylation using pyrosequencing is superior to BRAF codon 600 mutation status in identifying constitutional mutations in mismatch repair deficient tumours.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Neoplasias Colorretais Hereditárias sem Polipose/diagnóstico , Neoplasias Colorretais Hereditárias sem Polipose/genética , Metilação de DNA , Testes Genéticos , Neoplasias/genética , Proteínas Nucleares/genética , Regiões Promotoras Genéticas , Adulto , Alelos , Neoplasias Encefálicas/genética , Neoplasias Colorretais/genética , Ilhas de CpG , Testes Genéticos/métodos , Testes Genéticos/normas , Heterozigoto , Humanos , Pessoa de Meia-Idade , Proteína 1 Homóloga a MutL , Mutação , Síndromes Neoplásicas Hereditárias/genética , Proteínas Proto-Oncogênicas B-raf/genética , Sensibilidade e Especificidade
6.
Nat Genet ; 7(4): 525-30, 1994 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7951324

RESUMO

Huntington's disease (HD) correlates with abnormal expansion in a block of CAG repeats in the Huntington's disease gene. We have investigated HD evolution by typing CAG alleles in several human populations and in a variety of primates. We find that human alleles have expanded from a shorter ancestral state and exhibit unusual asymmetric length distributions. Computer simulations are used to show that the human state can be derived readily from a primate ancestor, without the need to invoke natural selection. The key element is a simple length-dependent mutational bias towards longer alleles. Our model can explain a number of empirical observations, and predicts an ever-increasing incidence of HD.


Assuntos
Evolução Biológica , Doença de Huntington/genética , Modelos Genéticos , Mutação , Alelos , Animais , Sequência de Bases , Simulação por Computador , Primers do DNA/genética , Frequência do Gene , Haplótipos , Humanos , Doença de Huntington/etiologia , Desequilíbrio de Ligação , Meiose/genética , Repetições Minissatélites , Dados de Sequência Molecular , Oligodesoxirribonucleotídeos/genética , Primatas
7.
Neoplasia ; 46: 100940, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37913654

RESUMO

Radiation therapy is an established and effective anti-cancer treatment modality. Extensive pre-clinical experimentation has demonstrated that the pro-inflammatory properties of irradiation may be synergistic with checkpoint immunotherapy. Radiation induces double-stranded DNA breaks (dsDNA). Sensing of the dsDNA activates the cGAS/STING pathway, producing Type 1 interferons essential to recruiting antigen-presenting cells (APCs). Radiation promotes cytotoxic CD8 T-cell recruitment by releasing tumour-associated antigens captured and cross-presented by surveying antigen-presenting cells. Radiation-induced vascular normalisation may further promote T-cell trafficking and drug delivery. Radiation is also immunosuppressive. Recruitment of regulatory T cells (Tregs) and innate cells such as myeloid-derived suppressive cells (m-MDSCs) all counteract the immunostimulatory properties of radiation. Many innate immune cell types operate at the interface of the adaptive immune response. Innate immune cells, such as m-MDSCs, can exert their immunosuppressive effects by expressing immune checkpoints such as PD-L1, further highlighting the potential of combined radiation and checkpoint immunotherapy. Several early-phase clinical studies investigating the combination of radiation and immunotherapy have been disappointing. A greater appreciation of radiotherapy's impact on the innate immune system is essential to optimise radioimmunotherapy combinations. This review will summarise the impact of radiotherapy on crucial cells of the innate immune system and vital immunosuppressive cytokines.


Assuntos
Antineoplásicos , Neoplasias , Humanos , Imunidade Inata , Neoplasias/radioterapia , Imunidade Adaptativa/efeitos da radiação , Antineoplásicos/farmacologia , Imunoterapia , Microambiente Tumoral
8.
Clin Exp Allergy ; 41(6): 783-93, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21492269

RESUMO

Identified factors from milk have been shown to improve health outcomes. One specific factor, transforming growth factor-Beta (TGF)-ß, has been identified previously as having the potential to impact on immunological outcomes in the newborn offspring. The primary objective of this review was to examine the published studies that have considered TGF-ß in association with immunological outcomes of experimental models. We hypothesized that oral administration of TGF-ß (through human milk, cow's milk, infant formula) or recombinant TGF-ß delivered via gavage, may down-regulate immune activation in newborn offspring. Animal experimental studies were identified through MEDLINE, CAB Abstracts, Biological Abstracts and Scopus. Selection criteria included well-described animal populations, sample and study design, source of TGF-ß, age and immunological outcomes measured and effect size. The findings were summarized temporally in tabular format, giving an overall measure of effect based on the literature available since 1994. Animal experimental studies (n=13) were included in the review to determine an association between maternal TGF-ß and immunological outcomes. Overall 92% of these studies (12/13) showed a positive association with TGF-ß1 or TGF-ß2, demonstrating protection against immunologically related outcomes in early life in an animal model. TGF-ß is important in developing and maintaining appropriate immune responses in the offspring. TGF-ß delivered orally to neonatal animals provides protection against adverse immunological outcomes, corroborating and supporting findings from human studies. Animal studies provide important clues to the pathogenesis and therapeutics of immune activation and allergy in early childhood. TGF-ßs are important growth factors involved in maintaining homeostasis in the intestine, regulating inflammation and allergy development and promoting oral tolerance in infants. Thus, taken as a whole, these and our other findings suggest that this cytokine in milk may influence the development of immunological outcomes in offspring.


Assuntos
Adjuvantes Imunológicos/farmacologia , Sistema Imunitário/efeitos dos fármacos , Leite/imunologia , Proteínas Recombinantes/farmacologia , Fator de Crescimento Transformador beta/farmacologia , Adjuvantes Imunológicos/administração & dosagem , Animais , Humanos , Proteínas Recombinantes/administração & dosagem , Fator de Crescimento Transformador beta/administração & dosagem
9.
Osteoporos Int ; 22(4): 1133-43, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20533029

RESUMO

UNLABELLED: Review of the 1-year prevalence of screening for osteoporosis and of osteoporosis or idiopathic fracture in Maryland Medicaid administrative records found that screening rates did not differ among women in the control population, women with psychosis, and women with major mood disorders, but were reduced compared to controls in women with substance use disorder, with or without psychosis. Prevalence of osteoporosis was increased compared to controls in women with major mood disorders or women over 55 dually diagnosed with psychosis and substance use disorder. INTRODUCTION: Osteoporosis is a major public health concern. Substance abuse and psychosis may be risk factors, however, frequency of screening and disease risk in women with psychotic disorders and substance use disorder (SUD) remains unknown. METHODS: This study examined rates (FY 2005) of osteoporosis screening and disease risk in Medicaid enrolled women aged 50 to 64 (N = 18,953). Four diagnostic groups were characterized: (1) psychosis, (2) SUD, (3) major mood disorder, and (4) controls. The interaction of psychosis and SUD on screening and disease prevalence of osteoporosis was tested. RESULTS: The prevalence of osteoporosis across the entire population was 6.7%. Four percent of those without an osteoporosis diagnosis received osteoporosis screening with no notable differences between psychosis and controls. Those with SUD, however, had a significant reduction in screening compared to controls (OR = 0.61, 95% CI = 0.40-0.91, p = 0.016). Women with a major mood disorder were more likely to have osteoporosis in their administrative record (OR = 1.32, 95% CI = 1.03-1.70, p = 0.028) compared to controls. Those who were dually diagnosed (SUD and psychosis) in the oldest ages (55-64 years) had a markedly higher prevalence of osteoporosis compared to controls (OR = 6.4 CI = 1.51-27.6, p = 0.012), whereas this interaction (SUD and psychosis) was not significant in the entire population over age 49. CONCLUSIONS: Osteoporosis screening in the Medicaid population is significantly lower for women with SUD, after adjusting for age, race, and Medicaid enrollment category. The prevalence of osteoporosis appears markedly elevated in those with major mood disorders and those over age 55 dually diagnosed with schizophrenia and SUD.


Assuntos
Programas de Rastreamento/estatística & dados numéricos , Osteoporose Pós-Menopausa/etiologia , Transtornos Psicóticos/complicações , Transtornos Relacionados ao Uso de Substâncias/complicações , Fatores Etários , Diagnóstico Duplo (Psiquiatria) , Métodos Epidemiológicos , Feminino , Humanos , Maryland/epidemiologia , Medicaid , Pessoa de Meia-Idade , Osteoporose Pós-Menopausa/diagnóstico , Osteoporose Pós-Menopausa/epidemiologia , Transtornos Psicóticos/epidemiologia , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Estados Unidos
10.
J Hosp Infect ; 111: 35-39, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33577834

RESUMO

BACKGROUND: The coronavirus disease 2019 pandemic has resulted in high levels of exposure of medical workers to severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). Hand decontamination is one of the actions recommended to reduce the risk of infection. AIM: Two disinfectants - BIAKOS antimicrobial skin and wound cleanser (AWC) and AWC2 (Sanara MedTech, Fort Worth, TX, USA) - were tested to determine whether they can inactivate SARS-CoV-2 upon contact or as a coating applied before contact with the virus. METHODS: The ability of AWC and AWC2 to inactivate SARS-CoV-2 was tested in liquid and dried form on plastic surfaces and porcine skin. FINDINGS: AWC and AWC2 were effective in reducing the infectious titre of SARS-CoV-2 in liquid form during application and in dried form 4 h after application. Virus on skin was reduced up to 2 log10-fold and 3.5 log10-fold after treatment with AWC and AWC2, respectively. CONCLUSION: Application of AWC and AWC2 to skin reduces the level of SARS-CoV-2 and the risk of infection.


Assuntos
Antivirais/administração & dosagem , COVID-19/prevenção & controle , Desinfecção das Mãos/métodos , Higienizadores de Mão/administração & dosagem , Viabilidade Microbiana/efeitos dos fármacos , Pele/virologia , Administração Tópica , Humanos , Pandemias , SARS-CoV-2
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