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1.
Hum Mol Genet ; 32(21): 3105-3120, 2023 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-37584462

RESUMO

DNA methyltransferase type 1 (DNMT1) is a major enzyme involved in maintaining the methylation pattern after DNA replication. Mutations in DNMT1 have been associated with autosomal dominant cerebellar ataxia, deafness and narcolepsy (ADCA-DN). We used fibroblasts, induced pluripotent stem cells (iPSCs) and induced neurons (iNs) generated from patients with ADCA-DN and controls, to explore the epigenomic and transcriptomic effects of mutations in DNMT1. We show cell type-specific changes in gene expression and DNA methylation patterns. DNA methylation and gene expression changes were negatively correlated in iPSCs and iNs. In addition, we identified a group of genes associated with clinical phenotypes of ADCA-DN, including PDGFB and PRDM8 for cerebellar ataxia, psychosis and dementia and NR2F1 for deafness and optic atrophy. Furthermore, ZFP57, which is required to maintain gene imprinting through DNA methylation during early development, was hypomethylated in promoters and exhibited upregulated expression in patients with ADCA-DN in both iPSC and iNs. Our results provide insight into the functions of DNMT1 and the molecular changes associated with ADCA-DN, with potential implications for genes associated with related phenotypes.


Assuntos
Ataxia Cerebelar , Surdez , Humanos , Ataxia Cerebelar/genética , DNA (Citosina-5-)-Metiltransferases/genética , Transcriptoma/genética , Epigenômica , DNA (Citosina-5-)-Metiltransferase 1/genética , Metilação de DNA/genética , Surdez/genética , Mutação , DNA
2.
Proc Natl Acad Sci U S A ; 118(22)2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-34035170

RESUMO

Heterozygous NRXN1 deletions constitute the most prevalent currently known single-gene mutation associated with schizophrenia, and additionally predispose to multiple other neurodevelopmental disorders. Engineered heterozygous NRXN1 deletions impaired neurotransmitter release in human neurons, suggesting a synaptic pathophysiological mechanism. Utilizing this observation for drug discovery, however, requires confidence in its robustness and validity. Here, we describe a multicenter effort to test the generality of this pivotal observation, using independent analyses at two laboratories of patient-derived and newly engineered human neurons with heterozygous NRXN1 deletions. Using neurons transdifferentiated from induced pluripotent stem cells that were derived from schizophrenia patients carrying heterozygous NRXN1 deletions, we observed the same synaptic impairment as in engineered NRXN1-deficient neurons. This impairment manifested as a large decrease in spontaneous synaptic events, in evoked synaptic responses, and in synaptic paired-pulse depression. Nrxn1-deficient mouse neurons generated from embryonic stem cells by the same method as human neurons did not exhibit impaired neurotransmitter release, suggesting a human-specific phenotype. Human NRXN1 deletions produced a reproducible increase in the levels of CASK, an intracellular NRXN1-binding protein, and were associated with characteristic gene-expression changes. Thus, heterozygous NRXN1 deletions robustly impair synaptic function in human neurons regardless of genetic background, enabling future drug discovery efforts.


Assuntos
Proteínas de Ligação ao Cálcio/genética , Mutação , Moléculas de Adesão de Célula Nervosa/genética , Neurônios/metabolismo , Neurotransmissores/metabolismo , Esquizofrenia/metabolismo , Estudos de Casos e Controles , Transdiferenciação Celular , Células Cultivadas , Estudos de Coortes , Células-Tronco Embrionárias/citologia , Expressão Gênica , Guanilato Quinases/metabolismo , Heterozigoto , Humanos , Células-Tronco Pluripotentes Induzidas/citologia
3.
Pediatr Nephrol ; 37(9): 2099-2107, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35041037

RESUMO

BACKGROUND: Acute kidney injury (AKI) in patients admitted to the pediatric intensive care unit (PICU) is associated with poor short-term and long-term outcomes. Greater awareness of long-term AKI-associated outcomes is needed to optimally plan follow-up and management after ICU discharge. We used propensity score methods to study associations between pediatric AKI and major adverse kidney outcomes, including mortality. METHODS: We included all children 6 months-18 years admitted to PICU at Seattle Children's Hospital from 7/1/2009 to 12/31/2018. Our primary outcome measure was Major Adverse Kidney Events at 30 days (MAKE30): creatinine > 200% of baseline, eGFR < 60 mL/min/1.73 m2, dialysis dependence, or mortality. Propensity scores for AKI development in PICU were generated using demographic, medical history, admission, and PICU hospitalization variables. Patients with AKI were matched to control patients without AKI. Logistic regression was used to test association between AKI status and MAKE30. RESULTS: In the unmatched cohort (n = 878), patients with AKI had lower platelet count (160 vs. 222) and higher PRISM III score (11 vs. 3.5). After propensity score matching, those with AKI vs. no AKI had similar PRISM III scores (9 vs. 10) and platelet count (163 vs. 159). AKI was significantly associated with MAKE30 after propensity score matching (OR: 2.97; 95% CI 1.82-4.84). CONCLUSIONS: Propensity score matching significantly reduced imbalance in baseline characteristics between those with and without AKI. After matching, AKI remained significantly associated with MAKE30. Patients who developed AKI were more likely to have abnormal kidney function at 30 and 90 days after ICU admission and may be at high risk for developing CKD in the future. A higher resolution version of the Graphical abstract is available as Supplementary information.


Assuntos
Injúria Renal Aguda , Diálise Renal , Injúria Renal Aguda/epidemiologia , Injúria Renal Aguda/etiologia , Injúria Renal Aguda/terapia , Criança , Estudos de Coortes , Humanos , Unidades de Terapia Intensiva Pediátrica , Rim , Pontuação de Propensão , Diálise Renal/efeitos adversos , Estudos Retrospectivos , Fatores de Risco
4.
Pediatr Emerg Care ; 38(8): 380-385, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35353794

RESUMO

OBJECTIVES: There is limited research examining racial/ethnic disparities in antiemetic use for acute gastroenteritis (AGE). We assessed racial/ethnic differences in the care of children with AGE. METHODS: The Pediatric Health Information System was used to conduct a retrospective cohort study of children 6 months to 6 years old with AGE seen in participating emergency departments from 2016 to 2018. Cases were identified using International Classification of Diseases, Tenth Revision codes. The primary outcome was administration of ondansetron, secondary outcomes were administration of intravenous (IV) fluids and hospitalization, and primary predictor was race/ethnicity. Multivariable logistic regression followed by a mixed model adjusted for sex, age, insurance, and hospital to examine the association of race/ethnicity with each outcome. RESULTS: There were 78,019 encounters included; 24.8% of patients were non-Hispanic White (NHW), 29.0% non-Hispanic Black (NHB), 37.3% Hispanic, and 8.9% other non-Hispanic (NH) race/ethnicity. Compared with NHW patients, minority children were more likely to receive ondansetron (NHB: adjusted odds ratio, 1.36 [95% confidence interval, 1.2-1.55]; Hispanic: 1.26 [1.1-1.44]; other NH: 1.22 [1.07-1.4]). However, minority children were less likely to receive IV fluids (NHB: 0.38 [0.33-0.43]; Hispanic: 0.44 [0.36-0.53]; other NH: 0.51 [0.44-0.61]) or hospital admission (NHB: 0.37 [0.29-0.48]; Hispanic: 0.41 [0.33-0.5]; other NH: 0.52 [0.41-0.66]). Ondansetron use by hospital ranged from 73% to 95%. CONCLUSIONS: This large database analysis of emergency departments around the nation found that NHW patients were less likely to receive ondansetron but more likely to receive IV fluids and hospital admission than minority patients. These findings are likely multifactorial and may represent bias, social determinants of health, access to care, or illness severity among other possible causes.


Assuntos
Gastroenterite , Ondansetron , Criança , Etnicidade , Gastroenterite/tratamento farmacológico , Hispânico ou Latino , Humanos , Ondansetron/uso terapêutico , Estudos Retrospectivos
5.
Epidemiol Infect ; 149: e75, 2021 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-33722335

RESUMO

We investigated whether countries with higher coverage of childhood live vaccines [BCG or measles-containing-vaccine (MCV)] have reduced risk of coronavirus disease 2019 (COVID-19)-related mortality, while accounting for known systems differences between countries. In this ecological study of 140 countries using publicly available national-level data, higher vaccine coverage, representing estimated proportion of people vaccinated during the last 14 years, was associated with lower COVID-19 deaths. The associations attenuated for both vaccine variables, and MCV coverage became no longer significant once adjusted for published estimates of the Healthcare access and quality index (HAQI), a validated summary score of healthcare quality indicators. The magnitude of association between BCG coverage and COVID-19 death rate varied according to HAQI, and MCV coverage had little effect on the association between BCG and COVID-19 deaths. While there are associations between live vaccine coverage and COVID-19 outcomes, the vaccine coverage variables themselves were strongly correlated with COVID-19 testing rate, HAQI and life expectancy. This suggests that the population-level associations may be further confounded by differences in structural health systems and policies. Cluster randomised studies of booster vaccines would be ideal to evaluate the efficacy of trained immunity in preventing COVID-19 infections and mortality in vaccinated populations and on community transmission.


Assuntos
COVID-19/imunologia , COVID-19/prevenção & controle , Imunidade Inata/imunologia , SARS-CoV-2/imunologia , Cobertura Vacinal/estatística & dados numéricos , Vacina BCG/administração & dosagem , Vacina BCG/imunologia , COVID-19/mortalidade , Atenção à Saúde/normas , Atenção à Saúde/estatística & dados numéricos , Humanos , Imunização Secundária/normas , Imunização Secundária/estatística & dados numéricos , Modelos Lineares , Vacina contra Sarampo/administração & dosagem , Vacina contra Sarampo/imunologia , Qualidade da Assistência à Saúde/normas , Qualidade da Assistência à Saúde/estatística & dados numéricos
6.
Sensors (Basel) ; 21(17)2021 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-34502674

RESUMO

With the construction and development of the BeiDou navigation satellite system (BDS), the precise point positioning (PPP) performance of the BDS is worthy of research. In this study, observational data from 17 stations around the world across 20 days are used to comprehensively evaluate the PPP performance of BDS B1c/B2a signals. For greater understanding, the results are also compared with the Global Positioning System (GPS) and BDS PPP performance of different signals and system combinations. The evaluation found root mean square (RMS) values of the static PPP in the north (N), east (E), and upward (U) components, based on the B1c/B2a frequency of BDS-3, to be 6.9 mm, 4.7 mm, and 26.6 mm, respectively. Similar to the static positioning, the RMS values of kinematic PPP in the three directions of N, E, and U are 2.6 cm, 6.0 cm, and 8.5 cm, respectively. Besides this, the static PPP of BDS-3 (B1cB2a) and BDS-2 + BDS-3 (B1IB3I) have obvious system bias. Compared with static PPP, kinematic PPP is more sensitive to the number of satellites, and the coordinate accuracy in three dimensions can be increased by 27% with the combination of GPS (L1L2) and BDS. Compared with BDS-2+BDS-3 (B1IB3I), the convergence time of BDS-3 (B1CB2a) performs better in both static and kinematic modes. The antenna model does not show a significant difference in terms of the effect of the convergence speed, though the number of satellites observed has a certain influence on the convergence time.

7.
J Pediatr Nurs ; 61: 280-283, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34375781

RESUMO

BACKGROUND: Screening for mental health comorbidities is recommended in adolescents and young adults (AYAs) with diabetes. There is a paucity of data on mental health comorbidities in AYAs with type 2 diabetes (T2D). OBJECTIVE: To assess rates of depression, suicidal ideation, and diabetes distress (DD) in AYAs with T2D overall and by sociodemographic and clinical factors. METHODS: AYAs with T2D ages 13-21 years seen in a pediatric diabetes clinic between March 2018 and June 2019 completed the Patient Health Questionnaire-9 (PHQ-9) for depression screening and the Problem Areas in Diabetes - teen version (PAID-T) survey to assess DD. Chi-square tests were used to assess whether rates of depression and DD were associated with participant characteristics. RESULTS: The sample consisted of 64 AYAs with T2D (58% female, mean age 15.8 ± 2.0 years, mean HbA1c 8.3% ± 2.6%, mean BMI z-score 2.2 ± 0.6, 59% on insulin). Overall, 31% of participants had high depression and/or DD. Twenty-two percent of participants reported high depressive symptoms and 9% endorsed suicidal ideation on the PHQ-9. There were no differences in rates of depression by sociodemographic factors. Twenty-three percent of participants reported high DD. Rates of DD were higher among those on insulin (p = 0.014) and on public health insurance (p = 0.014). CONCLUSIONS: Almost 1 in 3 AYAs with T2D endorsed depression and/or DD. Our findings support the importance of mental health screening in AYAs with T2D, as well as the need for strategies to address psychological comorbidities in this population.


Assuntos
Diabetes Mellitus Tipo 2 , Adolescente , Adulto , Criança , Depressão/diagnóstico , Depressão/epidemiologia , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/epidemiologia , Feminino , Humanos , Masculino , Saúde Mental , Fatores Sociodemográficos , Ideação Suicida , Adulto Jovem
8.
Plant Mol Biol ; 102(4-5): 373-388, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31872309

RESUMO

KEY MESSAGE: CRISPR-edited variants at the 3'-end of OsLOGL5's coding sequence (CDS), significantly increased rice grain yield under well-watered, drought, normal nitrogen, and low nitrogen field conditions at multiple geographical locations. Cytokinins impact numerous aspects of plant growth and development. This study reports that constitutive ectopic overexpression of a rice cytokinin-activation enzyme-like gene, OsLOGL5, significantly reduced primary root growth, tiller number, and yield. Conversely, mutations at the 3'-end of OsLOGL5 CDS resulted in normal rice plant morphology but with increased grain yield under well-watered, drought, normal nitrogen, and low nitrogen field conditions at multiple geographical locations. Six gene edited variants (Edit A to F) were created and tested in the field. Edit-B and Edit-F plants increased, but Edit-D and Edit-E plants decreased, the panicle number per plant. All OsLOGL5-edited plants significantly increased seed setting rate, total grain numbers, full-filled grain numbers per panicle, and thousand seed weight under drought conditions, suggesting that OsLOGL5 is likely involved in the regulation of both seed development and grain filling processes. Our results indicate that the C-terminal end of OsLOGL5 protein plays an important role in regulating rice yield improvement under different abiotic stress conditions, and OsLOGL5 is important for rice yield enhancement and stability.


Assuntos
Citocininas/metabolismo , Grão Comestível/genética , Oryza/genética , Proteínas de Plantas/metabolismo , Sistemas CRISPR-Cas , Secas , Grão Comestível/enzimologia , Edição de Genes , Regulação da Expressão Gênica de Plantas , Nitrogênio , Oryza/enzimologia , Proteínas de Plantas/genética , Raízes de Plantas/fisiologia , Domínios Proteicos , Sementes/fisiologia , Estresse Fisiológico
9.
Blood ; 132(6): 587-597, 2018 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-29884741

RESUMO

Understanding the profile of oncogene and tumor suppressor gene mutations with their interactions and impact on the prognosis of multiple myeloma (MM) can improve the definition of disease subsets and identify pathways important in disease pathobiology. Using integrated genomics of 1273 newly diagnosed patients with MM, we identified 63 driver genes, some of which are novel, including IDH1, IDH2, HUWE1, KLHL6, and PTPN11 Oncogene mutations are significantly more clonal than tumor suppressor mutations, indicating they may exert a bigger selective pressure. Patients with more driver gene abnormalities are associated with worse outcomes, as are identified mechanisms of genomic instability. Oncogenic dependencies were identified between mutations in driver genes, common regions of copy number change, and primary translocation and hyperdiploidy events. These dependencies included associations with t(4;14) and mutations in FGFR3, DIS3, and PRKD2; t(11;14) with mutations in CCND1 and IRF4; t(14;16) with mutations in MAF, BRAF, DIS3, and ATM; and hyperdiploidy with gain 11q, mutations in FAM46C, and MYC rearrangements. These associations indicate that the genomic landscape of myeloma is predetermined by the primary events upon which further dependencies are built, giving rise to a nonrandom accumulation of genetic hits. Understanding these dependencies may elucidate potential evolutionary patterns and lead to better treatment regimens.


Assuntos
Regulação Neoplásica da Expressão Gênica , Mieloma Múltiplo/genética , Mutagênese , Oncogenes , Células Clonais , Análise Mutacional de DNA , DNA de Neoplasias/genética , Conjuntos de Dados como Assunto , Dosagem de Genes , Estudo de Associação Genômica Ampla , Instabilidade Genômica , Genômica , Humanos , Perda de Heterozigosidade , Mieloma Múltiplo/patologia , Mutação , Prognóstico , Translocação Genética , Resultado do Tratamento , Sequenciamento do Exoma
10.
Haematologica ; 105(4): 1055-1066, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31221783

RESUMO

MYC is a widely acting transcription factor and its deregulation is a crucial event in many human cancers. MYC is important biologically and clinically in multiple myeloma, but the mechanisms underlying its dysregulation are poorly understood. We show that MYC rearrangements are present in 36.0% of newly diagnosed myeloma patients, as detected in the largest set of next generation sequencing data to date (n=1,267). Rearrangements were complex and associated with increased expression of MYC and PVT1, but not other genes at 8q24. The highest effect on gene expression was detected in cases where the MYC locus is juxtaposed next to super-enhancers associated with genes such as IGH, IGK, IGL, TXNDC5/BMP6, FAM46C and FOXO3 We identified three hotspots of recombination at 8q24, one of which is enriched for IGH-MYC translocations. Breakpoint analysis indicates primary myeloma rearrangements involving the IGH locus occur through non-homologous end joining, whereas secondary MYC rearrangements occur through microhomology-mediated end joining. This mechanism is different to lymphomas, where non-homologous end joining generates MYC rearrangements. Rearrangements resulted in overexpression of key genes and chromatin immunoprecipitation-sequencing identified that HK2, a member of the glucose metabolism pathway, is directly over-expressed through binding of MYC at its promoter.


Assuntos
Genes myc , Mieloma Múltiplo , RNA Longo não Codificante/genética , Genes de Cadeia Pesada de Imunoglobulina , Humanos , Hibridização in Situ Fluorescente , Mieloma Múltiplo/genética , Isomerases de Dissulfetos de Proteínas , Translocação Genética
11.
J Pediatr Gastroenterol Nutr ; 71(6): 749-754, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32910089

RESUMO

OBJECTIVES: Although abdominal pain is a hallmark symptom of pediatric inflammatory bowel disease (IBD), limited research has examined pain during the first year after diagnosis. The purpose of the present study is to examine prevalence, predictors, and impact of abdominal pain during the 12 months after pediatric IBD diagnosis using data from the ImproveCareNow (ICN) Network. PATIENTS AND METHODS: Participants consisted of 13,875 youth (age 8-18 years, 44% female, 81% Caucasian) with IBD (65% Crohn's disease; 27% ulcerative colitis, 8% indeterminate colitis) enrolled in the ICN Network with data from clinic visits during the first year after diagnosis (1-22 visits; mean = 3.7). Multivariable mixed effects logistic regression models were conducted to analyze the presence versus the absence of abdominal pain, activity limitations, and decrements in well-being. RESULTS: The percentage of youth reporting abdominal pain decreased significantly during the first year after diagnosis and yet a sizeable group reported continued pain at 12 months (55.9% at diagnosis; 34.0% at 12 months). Multivariable analyses revealed that greater time since diagnosis (odds ratio [OR] = 0.98, P < 0.001), higher disease severity (OR = 11.84, P < 0.001), presence of psychosocial risk factors (OR = 2.33, P = 0.036), and female sex (OR = 1.90, P < 0.010) were significant correlates of continuing abdominal pain. Abdominal pain was significantly associated with decrements in well-being (OR = 5.11, P < 0.001) as well as limitations in activity (OR = 9.31, P < 0.001), over and above the influence of disease severity. CONCLUSIONS: Abdominal pain is prevalent and impactful, even when controlling for disease activity, during the first year after pediatric IBD diagnosis. Results from the present study can inform screening and tailored pain management intervention efforts in pediatric IBD.


Assuntos
Dor Abdominal , Colite Ulcerativa , Doença de Crohn , Doenças Inflamatórias Intestinais , Dor Abdominal/diagnóstico , Dor Abdominal/epidemiologia , Dor Abdominal/etiologia , Adolescente , Criança , Colite Ulcerativa/complicações , Colite Ulcerativa/diagnóstico , Doença de Crohn/complicações , Doença de Crohn/diagnóstico , Feminino , Humanos , Doenças Inflamatórias Intestinais/complicações , Doenças Inflamatórias Intestinais/diagnóstico , Masculino , Índice de Gravidade de Doença
12.
Br J Haematol ; 184(4): 578-593, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30408155

RESUMO

Recent studies suggest that multiple myeloma (MM) induces proliferation and expansion of bone marrow (BM) mesenchymal stem cells (MSCs), but others showed that MM cells induce MSC senescence. To clarify the interaction between MM and MSCs, we exploited our established MSC gene signature to identify gene expression changes in myeloma MSCs and associated functional differences. Single MSCs from patients with MM had changes in expression of genes associated with cellular proliferation and senescence and a higher proportion of senescent cells and lower proliferative potential than those from age-matched healthy donors. Single MSCs from both sources heterogeneously express MSC genes associated with adipogenesis and osteoblastogenesis. We identified the gene encoding insulin-like growth factor-binding protein 2 (IGFBP2), an MSC gene commonly altered in high risk MM, as under-expressed. Morphologically, IGFBP2+ cells are underrepresented in MM BM compared to smouldering MM. Strong IGFBP2 and adiponectin co-expression was detected in a subset of small adipocytes. Co-culturing normal MSCs with myeloma cells suppressed MSC differentiation to adipocytes and osteoblasts, and reduced expression of IGFBP2 and adiponectin. Recombinant IGFBP2 blocked IGF1-mediated myeloma cell growth. Our data demonstrate that myeloma MSCs are less proliferative and that IGFBP2+ small adipocytes are a distinct mesenchymal cell population suppressed by myeloma.


Assuntos
Adipócitos , Medula Óssea , Regulação Neoplásica da Expressão Gênica , Proteína 2 de Ligação a Fator de Crescimento Semelhante à Insulina/biossíntese , Células-Tronco Mesenquimais , Mieloma Múltiplo , Proteínas de Neoplasias/biossíntese , Adipócitos/metabolismo , Adipócitos/patologia , Medula Óssea/metabolismo , Medula Óssea/patologia , Diferenciação Celular , Feminino , Humanos , Masculino , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/patologia , Mieloma Múltiplo/metabolismo , Mieloma Múltiplo/patologia , Fatores de Risco
13.
Biometrics ; 74(1): 313-320, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-28498490

RESUMO

This article proposes an efficient approach to screening genes associated with a phenotypic variable of interest in genomic studies with subgroups. In order to capture and detect various association profiles across subgroups, we flexibly estimate the underlying effect size distribution across subgroups using a semi-parametric hierarchical mixture model for subgroup-specific summary statistics from independent subgroups. We then perform gene ranking and selection using an optimal discovery procedure based on the fitted model with control of false discovery rate. Efficiency of the proposed approach, compared with that based on standard regression models with covariates representing subgroups, is demonstrated through application to a randomized clinical trial with microarray gene expression data in multiple myeloma, and through a simulation experiment.


Assuntos
Testes Genéticos , Modelos Estatísticos , Perfilação da Expressão Gênica , Humanos , Mieloma Múltiplo/genética , Análise de Sequência com Séries de Oligonucleotídeos , Ensaios Clínicos Controlados Aleatórios como Assunto
14.
Blood ; 124(13): 2051-60, 2014 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-25061178

RESUMO

Secreted protein CCN1, encoded by CYR61, is involved in wound healing, angiogenesis, and osteoblast differentiation. We identified CCN1 as a microenvironmental factor produced by mesenchymal cells and overexpressed in bones of a subset of patients with monoclonal gammopathy of undetermined significance (MGUS), asymptomatic myeloma (AMM), and multiple myeloma (MM). Our analysis showed that overexpression of CYR61 was independently associated with superior overall survival of MM patients enrolled in our Total Therapy 3 protocol. Moreover, elevated CCN1 was associated with a longer time for MGUS/AMM to progress to overt MM. During remission from MM, high levels of CCN1 were associated with superior progression-free and overall survival and stratified patients with molecularly defined high-risk MM. Recombinant CCN1 directly inhibited in vitro growth of MM cells, and overexpression of CYR61 in MM cells reduced tumor growth and prevented bone destruction in vivo in severe combined immunodeficiency-hu mice. Signaling through αvß3 was required for CCN1 prevention of bone disease. CYR61 expression may signify early perturbation of the microenvironment before conversion to overt MM and may be a compensatory mechanism to control MM progression. Therapeutics that upregulate CYR61 should be investigated for treating MM bone disease.


Assuntos
Doenças Ósseas/etiologia , Proteína Rica em Cisteína 61/genética , Expressão Gênica , Mieloma Múltiplo/complicações , Mieloma Múltiplo/genética , Microambiente Tumoral/genética , Animais , Doenças Assintomáticas , Biópsia , Medula Óssea/metabolismo , Medula Óssea/patologia , Osso e Ossos/patologia , Linhagem Celular Tumoral , Proteína Rica em Cisteína 61/sangue , Proteína Rica em Cisteína 61/metabolismo , Modelos Animais de Doenças , Progressão da Doença , Xenoenxertos , Humanos , Camundongos , Gamopatia Monoclonal de Significância Indeterminada/genética , Gamopatia Monoclonal de Significância Indeterminada/metabolismo , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/mortalidade , Prognóstico
15.
Opt Express ; 24(24): 27763-27770, 2016 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-27906344

RESUMO

Chiral plasmonic structures have been shown to possess large circular dichroism (CD) responses. Here, we investigate the CD responses in a solid and inverse metallic structure composed of a stacked right-twisted gammadion metallic nanoparticle and a left-twisted gammadion nanoaperture array, where a giant circular dichroism is achieved. In addition, the sign of the CD responses can be reversed through the changes of the geometric parameters. Further analysis reveals that the Fabry-Perot (F-P) resonance of cross-polarization conversion of electric field governs the change of the CD. It can be envisioned that our findings will allow further tuning and manipulation of the CD responses for tailored circular polarized light-matter interaction.

16.
BMC Bioinformatics ; 16: 63, 2015 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-25887219

RESUMO

BACKGROUND: Gene expression profiling (GEP) via microarray analysis is a widely used tool for assessing risk and other patient diagnostics in clinical settings. However, non-biological factors such as systematic changes in sample preparation, differences in scanners, and other potential batch effects are often unavoidable in long-term studies and meta-analysis. In order to reduce the impact of batch effects on microarray data, Johnson, Rabinovic, and Li developed ComBat for use when combining batches of gene expression microarray data. We propose a modification to ComBat that centers data to the location and scale of a pre-determined, 'gold-standard' batch. This modified ComBat (M-Combat) is designed specifically in the context of meta-analysis and batch effect adjustment for use with predictive models that are validated and fixed on historical data from a 'gold-standard' batch. RESULTS: We combined data from MIRT across two batches ('Old' and 'New' Kit sample preparation) as well as external data sets from the HOVON-65/GMMG-HD4 and MRC-IX trials into a combined set, first without transformation and then with both ComBat and M-ComBat transformations. Fixed and validated gene risk signatures developed at MIRT on the Old Kit standard (GEP5, GEP70, and GEP80 risk scores) were compared across these combined data sets. Both ComBat and M-ComBat eliminated all of the differences among probes caused by systematic batch effects (over 98% of all untransformed probes were significantly different by ANOVA with 0.01 q-value threshold reduced to zero significant probes with ComBat and M-ComBat). The agreement in mean and distribution of risk scores, as well as the proportion of high-risk subjects identified, coincided with the 'gold-standard' batch more with M-ComBat than with ComBat. The performance of risk scores improved overall using either ComBat or M-Combat; however, using M-ComBat and the original, optimal risk cutoffs allowed for greater ability in our study to identify smaller cohorts of high-risk subjects. CONCLUSION: M-ComBat is a practical modification to an accepted method that offers greater power to control the location and scale of batch-effect adjusted data. M-ComBat allows for historical models to function as intended on future samples despite known, often unavoidable systematic changes to gene expression data.


Assuntos
Algoritmos , Medula Óssea/metabolismo , Interpretação Estatística de Dados , Perfilação da Expressão Gênica/normas , Análise em Microsséries/métodos , Plasmócitos/metabolismo , Humanos
17.
Haematologica ; 100(9): 1214-21, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26022710

RESUMO

Multiple myeloma is preceded by an asymptomatic phase, comprising monoclonal gammopathy of uncertain significance and smoldering myeloma. Compared to the former, smoldering myeloma has a higher and non-uniform rate of progression to clinical myeloma, reflecting a subset of patients with higher risk. We evaluated the gene expression profile of smoldering myeloma plasma cells among 105 patients enrolled in a prospective observational trial at our institution, with a view to identifying a high-risk signature. Baseline clinical, bone marrow, cytogenetic and radiologic data were evaluated for their potential to predict time to therapy for symptomatic myeloma. A gene signature derived from four genes, at an optimal binary cut-point of 9.28, identified 14 patients (13%) with a 2-year therapy risk of 85.7%. Conversely, a low four-gene score (< 9.28) combined with baseline monoclonal protein < 3 g/dL and albumin ≥ 3.5 g/dL identified 61 patients with low-risk smoldering myeloma with a 5.0% chance of progression at 2 years. The top 40 probe sets showed concordance with indices of chromosome instability. These data demonstrate high discriminatory power of a gene-based assay and suggest a role for dysregulation of mitotic checkpoints in the context of genomic instability as a hallmark of high-risk smoldering myeloma.


Assuntos
Genes Neoplásicos , Instabilidade Genômica , Mieloma Múltiplo/genética , Proteínas de Neoplasias/genética , Idoso , Idoso de 80 Anos ou mais , Medula Óssea/patologia , Feminino , Humanos , Masculino , Mieloma Múltiplo/patologia , Estudos Prospectivos
18.
Stat Med ; 34(21): 2971-80, 2015 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-26084662

RESUMO

In multiple myeloma research, the GEP70 model is known to be capable of predicting a high risk patient group for disease progression based on the expression levels of 70 selected genes measured at baseline. The model consists of a continuous gene score that is a linear combination of the 70 genes along with a cutoff, such that patients with a score greater than the cutoff are categorized as high risk and otherwise low risk for disease progression. However, the continuous gene score may be confusing at times because of its open range nature. In addition, the present two-group model is sensitive to scores falling close to its cutoff. To facilitate patients' understanding of their prognosis, it is desirable to convert the continuous score into a probability that has an easier interpretation. In this article, we employ a latent class model to address this issue, and we also propose a superior grey zone model to refine the current risk stratification associated with the GEP70 model. Lastly, we demonstrate the robustness of the grey zone model with results from a simulation study.


Assuntos
Progressão da Doença , Modelos Estatísticos , Probabilidade , Medição de Risco/métodos , Algoritmos , Arkansas , Ensaios Clínicos como Assunto , Simulação por Computador , Intervalo Livre de Doença , Humanos , Mieloma Múltiplo/epidemiologia , Modelos de Riscos Proporcionais
19.
Inhal Toxicol ; 27(12): 621-8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26356830

RESUMO

This study aims to investigate the negative effects of chronic exposure to isoflurane on spermatogenesis and explore the underlying mechanisms. Sixty male rats were randomly allocated to two groups: control group, receiving no treatment, and anesthesia group, administrated exposure to isoflurane (2 ppm) for 25 consecutive days (1 h/day). The negative effects of chronic exposure to isoflurane were evaluated by analyzing the median eminence GnRH content, the relevant hormone levels, some sperm parameters and the mRNA expressions for some reproduction-related genes. Isoflurane significantly decreased the GnRH content and the serum gonadotrophin levels compared with the control group (p<0.01). Meanwhile, the mRNA expressions of GnRH in hypothalamus, GnRH receptor, luteinizing hormone (LH)-ß and follicle-stimulating hormone (FSH)-ß in pituitary, and LH receptor and FSH receptor in testes were also significantly inhibited (p<0.01). Furthermore, the mRNA expressions of androgen receptor (AR), kisspeptin encoded gene (Kiss-1) and its receptor (GPR54) in hypothalamus were significantly diminished by isoflurane (p<0.01). The results indicated that chronic exposure to isoflurane diminished the synthesis and secretion of GnRH by inhibiting the androgen-AR-Kisspeptin-GPR54 pathway and breaking the hypothalamic-pituitary-gonadal equilibrium, and therefore it could inhibit spermatogenesis.


Assuntos
Hipotálamo/efeitos dos fármacos , Exposição por Inalação/efeitos adversos , Isoflurano/toxicidade , Hipófise/efeitos dos fármacos , Espermatogênese/efeitos dos fármacos , Testículo/efeitos dos fármacos , Animais , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Sistema Hipotálamo-Hipofisário/metabolismo , Hipotálamo/metabolismo , Isoflurano/administração & dosagem , Masculino , Hipófise/metabolismo , Sistema Hipófise-Suprarrenal/efeitos dos fármacos , Sistema Hipófise-Suprarrenal/metabolismo , Ratos , Ratos Sprague-Dawley , Espermatogênese/fisiologia , Testículo/metabolismo
20.
Blood ; 119(2): 503-12, 2012 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-22072558

RESUMO

IL-6 signaling can be enhanced through transsignaling by the soluble IL-6 receptor (sIL-6r), allowing for the pleiotropic cytokine to affect cells it would not ordinarily have an effect on. Serum levels of sIL-6r can be used as an independent prognostic indicator and further stratify the GEP 70-gene low-risk group to identify an intermediate-risk group in multiple myeloma (MM). By analyzing more than 600 MM patients with ELISA, genotyping, and gene expression profiling tools, we show how the combination of 2 independent molecular genetic events is related to synergistic increases in sIL-6r levels. We also show that the rs2228145 minor allele is related to increased expression levels of an IL-6r splice variant that purportedly codes exclusively for a sIL-6r isoform. Together, the SNP rs2228145 minor allele C and amplification of chromosome 1q21 are significantly correlated to an increase in sIL-6r levels, which are associated with lower overall survival in 70-gene low-risk disease, and aid in identification of the intermediate-risk MM group.


Assuntos
Processamento Alternativo , Cromossomos Humanos Par 1/genética , Mieloma Múltiplo/sangue , Mieloma Múltiplo/genética , Polimorfismo de Nucleotídeo Único/genética , Receptores de Interleucina-6/sangue , Receptores de Interleucina-6/genética , Estudos de Casos e Controles , DNA/genética , Genótipo , Humanos , Perda de Heterozigosidade , Mieloma Múltiplo/mortalidade , Reação em Cadeia da Polimerase , Prognóstico , Fatores de Risco , Taxa de Sobrevida
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