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1.
Food Microbiol ; 108: 104092, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36088123

RESUMO

Escherichia coli shows the potential of indicating foodborne pathogens. The purpose of this study is to investigate the association between E. coli and foodborne pathogens such as Campylobacter, Salmonella, and Listeria in pastured poultry farms, as well as in related processing facilities. Five different sample types: (i) feces, (ii) soil, (iii) whole carcass rinse during processing (WCR-P), (iv) whole carcass rinse of final product after chilling and storage (WCR-F), and (v) ceca were measured for E. coli populations. A logistic regression model for pathogen presence was developed for each sample type. The E. coli population significantly increased the predicted probability of Salmonella presence for soil and WCR-P samples (p = 0.0011 and p = 0.0157 respectively). For Campylobacter, the initial prevalence in feces and ceca were high and a decreasing trend of detecting Campylobacter was observed as E. coli concentration increased. In soil and WCR-P models, the probability of the presence of Campylobacter significantly increased as E. coli population increased. These models provide a practical and effective way of evaluating the relationship between E. coli and foodborne pathogens and enable prediction of foodborne pathogen presence based on E. coli prevalence within the pastured poultry farm-to-fork continuum.


Assuntos
Campylobacter , Aves Domésticas , Animais , Galinhas , Escherichia coli , Fazendas , Salmonella , Solo
2.
Catheter Cardiovasc Interv ; 93(1): 97-104, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-30196566

RESUMO

OBJECTIVES: To externally validate the CRISP score, and determine if refinements might improve clinical utility. BACKGROUND: The CRISP score estimates risk of serious adverse events (SAEs) for pediatric catheterization. METHODS: Pediatric (age < 18) procedures reported to the Congenital Cardiovascular Interventional Study Consortium registry from 05/08 to 09/17 (n = 29,830, 27 centers) were divided into a development dataset of 14,784 earlier procedures, and a validation dataset of 15,046 more recent procedures. The development dataset was used to refit the original CRISP model, and to develop a revised(r) CRISP score, consisting of entirely pre-procedurally collected data. The validation dataset was then used to compare model fit and risk prediction between CRISP, rCRISP and two existing risk scores using Akaike's (AIC), Schwarz's (BIC) Bayes Information Criteria, -log Likelihood (N2LL), area under the receiver operator curve and chi-square goodness-of-fit statistic (across 5 risk categories). RESULTS: Overall 4.31% of patients experienced at least one SAE with frequency increasing from 1.08% in CRISP category 1 to 27.34% in category 5. Both CRISP and rCRISP (entirely pre-procedural) predicted risk of SAEs well, with observed to predicted ratios ranging from 0.71 to 1.18 across the 5 risk categories. Compared to the original CRISP score, rCRISP demonstrated less optimal model fit (higher AIC, BIC, and N2LL) but similar risk prediction (C-statistic = 0.71 vs. 0.70; chi-squared statistic = 6.77 vs. 6.85). CONCLUSION: The CRISP score accurately predicts procedural risk. With minor modifications, the revised version (rCRISP) performed well with arguably greater clinical utility as an entirely preprocedural risk model.


Assuntos
Cateterismo Cardíaco/efeitos adversos , Técnicas de Apoio para a Decisão , Cardiopatias Congênitas/terapia , Feminino , Cardiopatias Congênitas/diagnóstico , Cardiopatias Congênitas/fisiopatologia , Humanos , Lactente , Recém-Nascido , Masculino , Valor Preditivo dos Testes , Sistema de Registros , Reprodutibilidade dos Testes , Medição de Risco , Fatores de Risco
3.
Mamm Genome ; 29(9-10): 619-631, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30008145

RESUMO

Glutathione is a ubiquitous antioxidant that protects cells against reactive oxygen species and other chemical stressors. Despite its functional importance, the impact of genetics on the glutathione system has yet to be fully appreciated. Here, we investigated the heritability of glutathione levels and redox status in a disease-relevant condition: advanced age. We assembled a panel of 18-21-month-old mice representing 19 inbred strains and quantified the levels of reduced and oxidized glutathione, and their sums and ratios, in liver, kidney, heart, pancreas, cerebral cortex, and striatum. Heritability values were calculated for each phenotype and the results varied by tissue of origin. Cardiac glutathione phenotypes exhibited the highest heritabilities (G2 = 0.44-0.67), while striatal glutathione was least heritable (G2 = 0.11-0.29). Statistical relationships between tissues were evaluated, and the emergence of significant correlations suggested that despite tissue-specific heritabilities, at least some shared regulatory mechanisms may exist. Overall, these data highlight another mechanism by which genetic background determines antioxidant protection and stress resistance.


Assuntos
Glutationa/genética , Glutationa/metabolismo , Animais , Cérebro/metabolismo , Feminino , Glutationa/análise , Dissulfeto de Glutationa/análise , Dissulfeto de Glutationa/genética , Dissulfeto de Glutationa/metabolismo , Rim/metabolismo , Fígado/metabolismo , Camundongos , Camundongos Endogâmicos , Miocárdio/metabolismo , Especificidade de Órgãos , Pâncreas/metabolismo , Fenótipo , Característica Quantitativa Herdável , Especificidade da Espécie
4.
Catheter Cardiovasc Interv ; 87(2): 302-9, 2016 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-26527119

RESUMO

OBJECTIVES: We sought to develop a scoring system that predicts the risk of serious adverse events (SAE's) for individual pediatric patients undergoing cardiac catheterization procedures. BACKGROUND: Systematic assessment of risk of SAE in pediatric catheterization can be challenging in view of a wide variation in procedure and patient complexity as well as rapidly evolving technology. METHODS: A 10 component scoring system was originally developed based on expert consensus and review of the existing literature. Data from an international multi-institutional catheterization registry (CCISC) between 2008 and 2013 were used to validate this scoring system. In addition we used multivariate methods to further refine the original risk score to improve its predictive power of SAE's. RESULTS: Univariate analysis confirmed the strong correlation of each of the 10 components of the original risk score with SAE attributed to a pediatric cardiac catheterization (P < 0.001 for all variables). Multivariate analysis resulted in a modified risk score (CRISP) that corresponds to an increase in value of area under a receiver operating characteristic curve (AUC) from 0.715 to 0.741. CONCLUSION: The CRISP score predicts risk of occurrence of an SAE for individual patients undergoing pediatric cardiac catheterization procedures.


Assuntos
Cateterismo Cardíaco/efeitos adversos , Técnicas de Apoio para a Decisão , Cardiopatias Congênitas/terapia , Pediatria/métodos , Adolescente , Fatores Etários , Área Sob a Curva , Distribuição de Qui-Quadrado , Criança , Pré-Escolar , Cardiopatias Congênitas/diagnóstico , Humanos , Lactente , Recém-Nascido , Modelos Logísticos , Análise Multivariada , Valor Preditivo dos Testes , Curva ROC , Sistema de Registros , Reprodutibilidade dos Testes , Medição de Risco , Fatores de Risco , Resultado do Tratamento
5.
Nucleic Acids Res ; 42(5): 2870-8, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24371277

RESUMO

As biotechnology advances rapidly, a tremendous amount of cancer genetic data has become available, providing an unprecedented opportunity for understanding the genetic mechanisms of cancer. To understand the effects of duplications and deletions on cancer progression, two genomes (normal and tumor) were sequenced from each of five stomach cancer patients in different stages (I, II, III and IV). We developed a phylogenetic model for analyzing stomach cancer data. The model assumes that duplication and deletion occur in accordance with a continuous time Markov Chain along the branches of a phylogenetic tree attached with five extended branches leading to the tumor genomes. Moreover, coalescence times of the phylogenetic tree follow a coalescence process. The simulation study suggests that the maximum likelihood approach can accurately estimate parameters in the phylogenetic model. The phylogenetic model was applied to the stomach cancer data. We found that the expected number of changes (duplication and deletion) per gene for the tumor genomes is significantly higher than that for the normal genomes. The goodness-of-fit test suggests that the phylogenetic model with constant duplication and deletion rates can adequately fit the duplication data for the normal genomes. The analysis found nine duplicated genes that are significantly associated with stomach cancer.


Assuntos
Duplicação Gênica , Modelos Estatísticos , Filogenia , Neoplasias Gástricas/genética , Progressão da Doença , Deleção de Genes , Genes Duplicados , Humanos , Funções Verossimilhança , Modelos Genéticos
6.
Mol Cancer ; 12(1): 40, 2013 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-23663560

RESUMO

BACKGROUND: Co-Activator Arginine Methyltransferase 1(CARM1) is an Estrogen Receptor (ER) cofactor that remodels chromatin for gene regulation via methylation of Histone3. We investigated CARM1 levels and localization across breast cancer tumors in a cohort of patients of either European or African ancestry. METHODS: We analyzed CARM1 levels using tissue microarrays with over 800 histological samples from 549 female cancer patients from the US and Nigeria, Africa. We assessed associations between CARM1 expression localized to the nucleus and cytoplasm for 11 distinct variables, including; ER status, Progesterone Receptor status, molecular subtypes, ethnicity, HER2+ status, other clinical variables and survival. RESULTS: We found that levels of cytoplasmic CARM1 are distinct among tumor sub-types and increased levels are associated with ER-negative (ER-) status. Higher nuclear CARM1 levels are associated with HER2 receptor status. EGFR expression also correlates with localization of CARM1 into the cytoplasm. This suggests there are distinct functions of CARM1 among molecular tumor types. Our data reveals a basal-like subtype association with CARM1, possibly due to expression of Epidermal Growth Factor Receptor (EGFR). Lastly, increased cytoplasmic CARM1, relative to nuclear levels, appear to be associated with self-identified African ethnicity and this result is being further investigated using quantified genetic ancestry measures. CONCLUSIONS: Although it is known to be an ER cofactor in breast cancer, CARM1 expression levels are independent of ER. CARM1 has distinct functions among molecular subtypes, as is indicative of its sub-cellular localization and it may function in subtype etiology. These sub-cellular localization patterns, indicate a novel role beyond its ER cofactor function in breast cancer. Differential localization among ethnic groups may be due to ancestry-specific polymorphisms which alter the gene product.


Assuntos
Neoplasias da Mama/etnologia , Neoplasias da Mama/genética , Epigenômica , Proteína-Arginina N-Metiltransferases/genética , Adulto , População Negra , Neoplasias da Mama/metabolismo , Núcleo Celular/metabolismo , Citoplasma/metabolismo , Feminino , Humanos , Pessoa de Meia-Idade , Nigéria , Proteína-Arginina N-Metiltransferases/metabolismo , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo , Estados Unidos , População Branca
7.
Foodborne Pathog Dis ; 9(5): 473-9, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22506962

RESUMO

Campylobacter is a leading cause of foodborne illness in humans, and improving our understanding of the epidemiology of this organism is essential. The objective of this study was to identify the genes that discriminate isolates of C. jejuni by analysis with whole-genome DNA microarrays. Statistical analyses of whole-genome data from 95 geographically diverse cattle, chicken, and human C. jejuni isolates identified 142 most significant variable genes. Of this total, 125 (88%) belonged to genomic prophage and hypervariable regions. The significance of genomic prophage and hypervariable regions in determining C. jejuni isolate genomic diversity is emphasized by these results. These genes will be useful as biomarkers and components of genotyping systems for C. jejuni to improve our understanding of the epidemiology and population genetics of this major foodborne pathogen.


Assuntos
Infecções por Campylobacter/microbiologia , Campylobacter jejuni/classificação , Campylobacter jejuni/genética , Variação Genética , Carne/microbiologia , Prófagos/classificação , Prófagos/genética , Animais , Campylobacter jejuni/isolamento & purificação , Campylobacter jejuni/metabolismo , Bovinos , Galinhas , DNA Bacteriano/genética , DNA Bacteriano/isolamento & purificação , DNA Bacteriano/metabolismo , Microbiologia de Alimentos/métodos , Doenças Transmitidas por Alimentos/microbiologia , Loci Gênicos , Estudo de Associação Genômica Ampla , Técnicas de Genotipagem , Humanos , Internet , Análise de Sequência com Séries de Oligonucleotídeos , Vigilância da População , Prófagos/isolamento & purificação , Prófagos/metabolismo , Estados Unidos
8.
Food Res Int ; 161: 111860, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36192982

RESUMO

Though most strains of E. coli are non-pathogenic components of the intestinal microbiome, certain pathogenic E. coli strains are the cause of diseases and outbreaks. Poultry is identified as a common reservoir for pathogenic E. coli. It is important to identify farm practice factors associated with E. coli in the pastured poultry environment. The objective of this study is to develop models that can predict E. coli levels and to select farm practice factors contributing to E. coli concentration in pastured poultry farms. Five kinds of samples: feces, soil, whole carcass rinse after processing (WCR-P), final product after chilling and storage (WCR-F), and ceca samples were collected for E. coli counts from 11 pastured poultry farms in the southeastern US. The regression tree (RT) and least absolute shrinkage and selection operator (LASSO) methods were applied to data from each sample type. The farm management practices and processing factors such as source of eggs, type of feed used, appearance of other animals on farm, chilling method, and storage time and temperature were all considered as possible explanatory factors in the models. Models were developed to predict the levels of E. coli and to select the most important factors used in predicting E. coli population. Model performances were compared using root mean square error (RMSE). For feces samples, average number of birds and animal source were the two most important variables affecting E. coli population by LASSO. The RT selected animal source, brood feed, day of year, flock age in days, and flock size as the most important variables in predicting E. coli concentration. The RMSE (in log10 scale) under LASSO was 0.974, while under RT it was 1.032 for feces samples. The predictive models provide practical and effective tools to predict E. coli population and to identify farm practice factors that affect E. coli levels.


Assuntos
Escherichia coli , Aves Domésticas , Animais , Fazendas , Fezes , Solo
9.
J Biol Chem ; 285(38): 29375-86, 2010 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-20634284

RESUMO

Recent studies have indicated that lipopolysaccharides (LPS) isolated from particular bacterial strains can bias innate immune responses toward different signal transduction pathways thereby eliciting unique patterns of cytokines. Heterogeneity in the structure of lipid A (the active component of LPS) and possible contaminations with other inflammatory components have made it difficult to confirm these observations and dissect molecular motifs that may be responsible for modulatory properties. To address these issues, we have examined, for the first time, the ability of a range of well defined synthetic lipid As and isolated LPS and lipid A preparations to induce the production of a wide range of cytokines in three different mouse cell types. It was found that, for a given compound, the potencies of production of the various cytokines differed significantly. An additive model, in which a chemical change in the structure of a compound effects the potencies of all cytokines in the same manner, could describe the potencies of the cytokines for all compounds. Thus, no evidence was found that the structure of lipid A can modulate the pattern of cytokine production. In addition, the statistical analysis showed that the relative ordering of the potencies of the compounds was identical in the different cell types and that structural features such as the presence of a 3-deoxy-D-manno-octulosonic acid moiety, anomeric phosphate, lipid length, and acylation pattern were important for pro-inflammatory activity. Finally, it was found that transcriptional and post-transcription control mechanisms determine potencies and efficacies of cytokine production in cell-specific manners.


Assuntos
Imunidade Inata/imunologia , Lipídeo A/imunologia , Animais , Linhagem Celular , Citocinas/genética , Citocinas/imunologia , Ensaio de Imunoadsorção Enzimática , Imunidade Inata/genética , Lipídeo A/análogos & derivados , Lipídeo A/síntese química , Camundongos , Reação em Cadeia da Polimerase
10.
J Am Coll Health ; 69(5): 470-477, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-31662045

RESUMO

OBJECTIVES: This study assesses students' non-medical use of prescription drugs (NMUPD) from college entrance to graduation, and examines factors that predict NMUPD. Participants: The study was conducted between May 2011 and September 2015 with 338 students. Methods: Longitudinal cohort study design was used to examine NMUPD across time, and NMUPD-related attitudes and subjective norms. Five yearly interviews were conducted to collect data. Cox proportional hazards regression analysis was used to examine time to NMUPD. Results: Thirty-five percent of study participants reported NMUPD; the majority of those initiated non-medical use before their third year in college. Analyses indicated that more positive attitudes towards NMUPD (HR = 1.73, p < 0.001), increased subjective norms regarding NMUPD (HR = 1.01, p < 0.01), and gender (male) (HR= 1.89, p < 0.001) were significantly associated with sooner NMUPD. Conclusions: Findings suggest that NMUPD prevention efforts that target mutable factors such as attitudes and subjective norms should be implemented early during students' college careers.


Assuntos
Uso Indevido de Medicamentos sob Prescrição , Medicamentos sob Prescrição , Humanos , Estudos Longitudinais , Masculino , Estudantes , Análise de Sobrevida , Universidades
11.
PLoS One ; 16(8): e0255922, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34388196

RESUMO

Tillering and secondary branching are two plastic traits with high agronomic importance, especially in terms of the ability of plants to adapt to changing environments. We describe a quantitative trait analysis of tillering and secondary branching in two novel BC1F2 populations totaling 246 genotypes derived from backcrossing two Sorghum bicolor x S. halepense F1 plants to a tetraploidized S. bicolor. A two-year, two-environment phenotypic evaluation in Bogart, GA and Salina, KS permitted us to identify major effect and environment specific QTLs. Significant correlation between tillering and secondary branching followed by discovery of overlapping sets of QTLs continue to support the developmental relationship between these two organs and suggest the possibility of pleiotropy. Comparisons with two other populations sharing S. bicolor BTx623 as a common parent but sampling the breadth of the Sorghum genus, increase confidence in QTL detected for these two plastic traits and provide insight into the evolution of morphological diversity in the Eusorghum clade. Correspondence between flowering time and vegetative branching supports other evidence in suggesting a pleiotropic effect of flowering genes. We propose a model to predict biomass weight from plant architecture related traits, quantifying contribution of each trait to biomass and providing guidance for future breeding experiments.


Assuntos
Melhoramento Vegetal , Sorghum , Mapeamento Cromossômico , Fenótipo , Locos de Características Quantitativas
12.
J Natl Med Assoc ; 111(3): 246-255, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30389146

RESUMO

BACKGROUND: The Medicare Modernization Act (MMA) drastically reduced reimbursement for androgen deprivation therapy (ADT) in 2005. One unintended consequence of the MMA may be an increase in the racial disparities in receipt of ADT. Given these policy changes, it becomes increasingly important to assess racial disparities in timely receipt of ADT. METHODS: The purpose of this study is to evaluate the associations between race and median time to receipt of ADT among men with metastatic prostate cancer before and after the passage of the MMA. A population-based retrospective cohort was created from the Surveillance, Epidemiology, and End Results-Medicare. RESULTS: A total of 1,846 African-American and 9,462 Caucasian men diagnosed with metastatic prostate cancer from 2000 through 2011 were included. An accelerated failure time regression model was used to examine factors associated with racial differences in median time to receipt of ADT. Results indicate that African-American men had a longer median time to receipt of ADT both before the MMA (Time Ratio (TR): 1.15; 95% Confidence Interval (CI) [1.05, 1.27]) and after the MMA (TR: 1.29; 95% CI [1.10, 1.53]) as compared to Caucasian men. In addition to race, men residing in South had longer median time to receipt of ADT (TR: 1.26, 1.52; 95% CI [1.01, 1.52; 1.24, 1.87] before and after MMA, respectively) compared to the Northeast region. CONCLUSION: Considering the palliative benefits of ADT, it is important to develop effective strategies to address racial differences in receipt of treatment for metastatic prostate cancer.


Assuntos
Antagonistas de Androgênios/uso terapêutico , Negro ou Afro-Americano/estatística & dados numéricos , Disparidades em Assistência à Saúde/etnologia , Neoplasias da Próstata/tratamento farmacológico , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Disparidades em Assistência à Saúde/estatística & dados numéricos , Humanos , Masculino , New England , Neoplasias da Próstata/etnologia , Estudos Retrospectivos , Programa de SEER , Sudeste dos Estados Unidos , Fatores de Tempo , População Branca/estatística & dados numéricos
13.
Am J Cardiol ; 123(9): 1527-1531, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-30797558

RESUMO

The purpose of this study was to define the risk for adults with congenital heart disease who underwent cardiac catheterization and to propose a precatheterization risk scoring system. Data were prospectively collected using a multicenter registry of the Congenital Cardiovascular Interventional Study Consortium. The occurrence of serious adverse events (SAE) was correlated with 12 predefined variables. Catheterization RISk in Adult patients (CRISA) score was derived using multivariate logistic regression with backward elimination model selection method. The CRISA score was compared with the American Society of Anesthesiology score and a consensus-derived, 20-point risk score based on their ability to predict SAE. From June 2008 to September 2017, 300 adjudicated SAE's occurred in 7317 catheterization procedures (overall SAE rate 4.1%) performed in adults over 18 years of age at 27 contributing centers. Nine of the 12 tested variables were ultimately included in the CRISA score. CRISA score positively correlated with risk of SAE, and was superior to American Society of Anesthesiology and the 20-point risk score in predicting SAE. Minimal (CRISA score 0 to 2), low (3 to 7), moderate (8 to 10) and high (≥11) risk categories were identified, corresponding to 0.5%, 3.2%, 7.9%, and 16.7% risk of SAE, respectfully. In conclusion, the CRISA score reliably predicts risk of SAE in adults with congenital heart disease who underwent cardiac catheterization and may be useful for preprocedural risk assessment.


Assuntos
Cateterismo Cardíaco/efeitos adversos , Cardiopatias Congênitas/diagnóstico , Medição de Risco/métodos , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sistema de Registros , Estudos Retrospectivos , Fatores de Risco , Adulto Jovem
14.
J Gerontol A Biol Sci Med Sci ; 71(12): 1560-1563, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-26774117

RESUMO

Growth differentiation factor 11 (GDF11) is member of the transforming growth factor ß (TGF-ß) superfamily of proteins. Circulating GDF11 concentrations appear to decline with age, and its depletion is associated with cardiac hypertrophy and other morbidities. Knowledge of GDF11 regulation is limited, and the effects of natural genetic variation on GDF11 levels are currently undefined. We tested whether genetic background determines serum GDF11 concentrations using two classical inbred mouse strains: C57BL/6J (B6) and BALB/cByJ (BALB). B6 mice exhibited significantly higher GDF11 levels than BALB mice, and these strain differences were consistent throughout the life span. Overall, interactions between age and genetic background determined GDF11 concentrations, which were unaffected by sex. We then surveyed a panel of 22 genetically diverse inbred mouse strains and discovered a sixfold range in GDF11 levels at middle age. We estimated that 74.52% of phenotypic variation in GDF11 levels was attributable to genetic background. We used the Mouse Phenome Database to screen for phenotypes that correlate with GDF11. Interestingly, GDF11 levels predicted median strain life spans. This study revealed high heritability of GDF11 levels. Furthermore, our correlative data suggest that GDF11 may serve as a novel predictor of mammalian life span.


Assuntos
Envelhecimento/sangue , Fatores de Diferenciação de Crescimento/sangue , Fatores de Diferenciação de Crescimento/genética , Longevidade/genética , Animais , Biomarcadores/sangue , Proteínas Morfogenéticas Ósseas , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Masculino , Camundongos , Camundongos Endogâmicos C57BL
15.
Oecologia ; 92(3): 416-428, 1992 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28312609

RESUMO

Nestedness of species assemblages occurs when thebiotas of sites with lower numbers of species tend to be subsets of the biotas at richer sites. We develop new quantitative and statistical techniques for measuring, testing, and comparing nestedness, and apply these methods to data from the literature. Significantly nonrandom nestedness was present in all 27 assemblages examined, and tended to be stronger in systems dominated by extinction, such as landbridge islands. Sets of assemblages that were very strongly nested were more likely to have greater species richness on one or a few large sites than on several smaller sites of equivalent total area - that is, to fall toward the "single large" side of the "Single Large Or Several Small" (SLOSS) continuum. Our analysis indicates that nestedness, when quantified as a single number for a presence-absence matrix, measures community-wide differences in incidence (the frequency of occurrence or "distribution" of species). Factors that lead to consistent differences among species in immigration or extinction rates cause strong patterns of nestedness of species assemblages. Nestedness is negatively related to beta diversity: nestedness is low when beta diversity is high, and vice versa. Conservation managers will thus seek to minimize nestedness and the development of nested structure in systems of nature reserves.

16.
J Clin Pharmacol ; 53(5): 567-73, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23553619

RESUMO

Adverse drug reactions (ADRs) increase morbidity, mortality, and hospital costs in children treated in the Pediatric Intensive Care Unit (PICU). Few studies have reported the incidence and risk factors of ADRs in PICU. Our study aimed to evaluate incidence, risk factors, and economic burden of ADRs in PICU. An intensive ADR surveillance was conducted at the PICU of Children's Hospital of Michigan between November 1, 2010 and May 31, 2011. A trigger list was used to screen for suspected ADR cases. Of the 697 consecutive PICU admissions reviewed, 13.1% experienced at least one episode of ADR. The ADR incidence was 22% in patients with cardiovascular (CV) surgery and 11.5% in other patients. The most frequently detected ADR was electrolyte imbalance associated with diuretic exposure. Mean age at admission was 4 years (interquartile range: 9 months-13 years). Risk factors for ADR included young age (<1 year), Pediatric Risk of Mortality (PRISM) score upon admission ≥3, and administration of ≥16 medications. ADRs increased total ICU costs by 3.5-fold and length of ICU stay by 3.8-fold. Increased ADR surveillance of high risk patients in conjunction with early intervention may reduce drug related morbidity and costs in the PICU.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/economia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Unidades de Terapia Intensiva Pediátrica/economia , Centros de Atenção Terciária/economia , Adolescente , Criança , Pré-Escolar , Feminino , Custos Hospitalares , Hospitalização/economia , Hospitalização/estatística & dados numéricos , Humanos , Incidência , Lactente , Unidades de Terapia Intensiva Pediátrica/estatística & dados numéricos , Tempo de Internação/estatística & dados numéricos , Masculino , Fatores de Risco , Centros de Atenção Terciária/estatística & dados numéricos
17.
J Clin Pharmacol ; 53(1): 87-95, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23400748

RESUMO

Critically ill newborns in neonatal intensive care units (NICUs) are at greater risk of developing adverse drug reactions (ADRs). Differentiation of ADRs from reactions associated with organ dysfunction/immaturity is difficult. Current ADR algorithm scoring was established arbitrarily without validation in infants. The study objective was to develop a valid and reliable algorithm to identify ADRs in the NICU. Algorithm development began with a 24-item questionnaire for data collection on 100 previously suspected ADRs. Five pediatric pharmacologists independently rated cases as definite, probable, possible, and unlikely ADRs. Consensus "gold standard" was reached via teleconference. Logistic regression and iterative C programs were used to derive the scoring system. For validation, 50 prospectively collected ADR cases were assessed by 3 clinicians using the new algorithm and the Naranjo algorithm. Weighted kappa and intraclass correlation coefficient (ICC) were used to compare validity and reliability of algorithms. The new algorithm consists of 13 items. Kappa and ICC of the new algorithm were 0.76 and 0.62 versus 0.31 and 0.43 for the Naranjo algorithm. The new algorithm developed using actual patient data is more valid and reliable than the Naranjo algorithm for identifying ADRs in the NICU population. Because of the relatively small and nonrandom samples, further refinement and additional testing are needed.


Assuntos
Algoritmos , Monitoramento de Medicamentos/métodos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/diagnóstico , Unidades de Terapia Intensiva Neonatal , Farmacovigilância , Feminino , Hospitais Pediátricos , Humanos , Lactente , Recém-Nascido , Masculino , Ontário , Reprodutibilidade dos Testes
18.
PLoS One ; 6(6): e20671, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21695121

RESUMO

An ensemble of genetic networks that describe how the model fungal system, Neurospora crassa, utilizes quinic acid (QA) as a sole carbon source has been identified previously. A genetic network for QA metabolism involves the genes, qa-1F and qa-1S, that encode a transcriptional activator and repressor, respectively and structural genes, qa-2, qa-3, qa-4, qa-x, and qa-y. By a series of 4 separate and independent, model-guided, microarray experiments a total of 50 genes are identified as QA-responsive and hypothesized to be under QA-1F control and/or the control of a second QA-responsive transcription factor (NCU03643) both in the fungal binuclear Zn(II)2Cys6 cluster family. QA-1F regulation is not sufficient to explain the quantitative variation in expression profiles of the 50 QA-responsive genes. QA-responsive genes include genes with products in 8 mutually connected metabolic pathways with 7 of them one step removed from the tricarboxylic (TCA) Cycle and with 7 of them one step removed from glycolysis: (1) starch and sucrose metabolism; (2) glycolysis/glucanogenesis; (3) TCA Cycle; (4) butanoate metabolism; (5) pyruvate metabolism; (6) aromatic amino acid and QA metabolism; (7) valine, leucine, and isoleucine degradation; and (8) transport of sugars and amino acids. Gene products both in aromatic amino acid and QA metabolism and transport show an immediate response to shift to QA, while genes with products in the remaining 7 metabolic modules generally show a delayed response to shift to QA. The additional QA-responsive cutinase transcription factor-1ß (NCU03643) is found to have a delayed response to shift to QA. The series of microarray experiments are used to expand the previously identified genetic network describing the qa gene cluster to include all 50 QA-responsive genes including the second transcription factor (NCU03643). These studies illustrate new methodologies from systems biology to guide model-driven discoveries about a core metabolic network involving carbon and amino acid metabolism in N. crassa.


Assuntos
Genes Fúngicos/genética , Família Multigênica/genética , Neurospora crassa/genética , Ácido Quínico/metabolismo , Biologia de Sistemas , Sítios de Ligação , Biologia Computacional , Perfilação da Expressão Gênica , Regulação Fúngica da Expressão Gênica/efeitos dos fármacos , Redes Reguladoras de Genes/genética , Cinética , Análise dos Mínimos Quadrados , Modelos Genéticos , Neurospora crassa/efeitos dos fármacos , Análise de Sequência com Séries de Oligonucleotídeos , Ácido Quínico/farmacologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
19.
Curr Med Res Opin ; 23(6): 1351-65, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17559734

RESUMO

BACKGROUND: Prescribing adjunctive mood stabilizers to manage schizophrenia is prevalent, despite the lack of substantial evidence to support the long-term use of this treatment regimen. OBJECTIVE: The objective of this study was to assess the impact of using adjunctive mood stabilizers on antipsychotic utilization, total health expenditures, inpatient hospitalizations, long-term care stays, and emergency room (ER) visits for patients with schizophrenia. METHODS: Georgia Medicaid claims from 1999 through 2001 were analyzed to identify recipients diagnosed with schizophrenia (International Classification of Diseases, Ninth Revision, Clinical Modification [ICD-9-CM]: 295. XX). The treatment groups consisted of subjects who received combination therapy of mood stabilizers and antipsychotics (including both atypical and typical medications), while the comparison group consisted of subjects who were on antipsychotic medications without exposure to the mood stabilizers under investigation. Four treatment groups (valproate, lithium, carbamazepine, and combination mood stabilizer therapy) were formed based on the mood stabilizers patient received. Differences in annual health care use and expenditures were estimated between propensity score matched treatment and comparison groups controlling for comorbidity, prior utilization, demographic, and health provider specialty. RESULTS: During the 1-year observation period, subjects in treatment groups filled an average of 200-days supply of adjunctive mood stabilizers. These adjunctive mood stabilizer recipients had significantly longer antipsychotic treatment durations than the subjects who did not have exposure to mood stabilizers (valproate + antipsychotic vs. antipsychotic only, net difference: 56.47 days, p < 0.0001; lithium + antipsychotic vs. antipsychotic only, net difference: 90.25 days, p < 0.0001; carbamazepine + antipsychotic vs. antipsychotic only, net difference: 41.27 days, p = 0.0439; multiple mood stabilizers + antipsychotic vs. antipsychotic only, net difference: 83.14 days, p < 0.0001). The intensive pharmacotherapy associated with treatment groups resulted in $900-$1300 higher pharmacy costs than the comparison groups (valproate + antipsychotic vs. antipsychotic only, net difference: $1218.43, p < 0.0001; lithium + antipsychotic vs. antipsychotic only, net difference: $985.79, p = 0.0015; carbamazepine + antipsychotic vs. antipsychotic only, net difference: $911.63, p = 0.0497; multiple mood stabilizers + antipsychotic vs. antipsychotic only, net difference: $1281.91, p < 0.0047). However, there were no statistically significant differences for total health expenditures, hospitalizations, emergency room visits, and nursing home admissions between propensity-matched treatment and control groups. CONCLUSIONS: There were no differences in health care costs or utilization of ER, long-term care, and inpatient services between schizophrenia patients who did and did not receive adjunctive mood stabilizer; however, longer antipsychotic treatment durations were observed in patients receiving adjunctive mood stabilizers. Interpretation of these results is limited by the unknown selection bias between the treatment and the comparison groups and the relatively small number of patients in some treatment groups. The development of a better-controlled study to further evaluate this treatment regimen is warranted.


Assuntos
Antimaníacos/uso terapêutico , Antipsicóticos/uso terapêutico , Recursos em Saúde/estatística & dados numéricos , Medicaid , Esquizofrenia/tratamento farmacológico , Adulto , Afeto/efeitos dos fármacos , Algoritmos , Antimaníacos/economia , Antipsicóticos/economia , Carbamazepina/economia , Carbamazepina/uso terapêutico , Quimioterapia Adjuvante , Estudos de Coortes , Serviço Hospitalar de Emergência/economia , Serviço Hospitalar de Emergência/estatística & dados numéricos , Recursos em Saúde/economia , Hospitalização/estatística & dados numéricos , Humanos , Tempo de Internação/estatística & dados numéricos , Compostos de Lítio/economia , Compostos de Lítio/uso terapêutico , Assistência de Longa Duração/economia , Assistência de Longa Duração/estatística & dados numéricos , Estudos Retrospectivos , Resultado do Tratamento , Estados Unidos , Ácido Valproico/economia , Ácido Valproico/uso terapêutico
20.
Med Care ; 45(5): 472-6, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17446834

RESUMO

BACKGROUND: Potentially inappropriate medication (PIM) use is a major source of drug-related problems in the elderly. Few studies have quantified the effect of PIM use on total healthcare expenditures in the United States. OBJECTIVES: : We sought to determine the relationship between PIM use and healthcare expenditure and to estimate the annual incremental healthcare expenditures related to PIM use in the community-dwelling elderly population in the United States in 2001. METHODS: This was a retrospective cohort study. Participants were age 65 years or older who had no PIM use in rounds 1 and 2 of the 2000-2001 Medical Expenditure Panel Survey, a nationally representative survey of the US noninstitutionalized population. On the basis of the 2002 Beers criteria, PIM users were identified as those who had been prescribed at least one PIM during specified time periods in the study. Propensity scores were used to match PIM users and nonusers in the analysis examining differences in total healthcare expenditures. RESULTS: PIM utilization is a significant predictor for higher healthcare expenditures (P < 0.05). A conservative estimate of the incremental healthcare expenditures related to PIM use in the community-dwelling elderly population would be $7.2 billion (95% confidence interval, $3.4 billion-$15.7 billion) in the United States in 2001. CONCLUSIONS: PIM use is a major patient safety concern that results in increased healthcare expenditures. This study emphasizes the need for continued provider education to inform prescribers of the potential risks of using certain medications in the elderly and to improve prescribing practices.


Assuntos
Gastos em Saúde/tendências , Serviços de Saúde para Idosos/economia , Erros de Medicação/economia , Atividades Cotidianas , Idoso , Estudos de Coortes , Feminino , Pesquisas sobre Atenção à Saúde , Serviços de Saúde para Idosos/normas , Humanos , Masculino , Erros de Medicação/tendências , Características de Residência , Estudos Retrospectivos , Estados Unidos
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