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1.
Rheumatology (Oxford) ; 54(4): 736-42, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25252703

RESUMO

OBJECTIVE: The aim of this study was to integrate and examine the association between NSAID use and venous thromboembolism (VTE). METHODS: We conducted a systematic review and meta-analysis of studies that reported odds ratios, relative risks, hazard ratios or standardized incidence ratios for VTE among NSAID users compared with non-users. Pooled risk ratios and 95% CIs were calculated using a random effects generic inverse variance model. RESULTS: Six studies with 21 401 VTE events were identified and included in the data analysis. The pooled risk ratio of VTE in NSAID users was 1.80 (95% CI 1.28, 2.52). CONCLUSION: Our study demonstrated a statistically significant increased risk of VTE among NSAID users. This finding has important public health implications given the prevalence of NSAID use in the general population.


Assuntos
Anti-Inflamatórios não Esteroides/uso terapêutico , Embolia Pulmonar/epidemiologia , Tromboembolia Venosa/epidemiologia , Trombose Venosa/epidemiologia , Anti-Inflamatórios não Esteroides/efeitos adversos , Humanos , Incidência , Razão de Chances , Modelos de Riscos Proporcionais , Embolia Pulmonar/induzido quimicamente , Tromboembolia Venosa/induzido quimicamente , Trombose Venosa/induzido quimicamente
2.
Proc Natl Acad Sci U S A ; 109(7): 2678-83, 2012 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-22308420

RESUMO

Photosynthesis has recently gained considerable attention for its potential role in the development of renewable energy sources. Optimizing photosynthetic organisms for biomass or biofuel production will therefore require a systems understanding of photosynthetic processes. We reconstructed a high-quality genome-scale metabolic network for Synechocystis sp. PCC6803 that describes key photosynthetic processes in mechanistic detail. We performed an exhaustive in silico analysis of the reconstructed photosynthetic process under different light and inorganic carbon (Ci) conditions as well as under genetic perturbations. Our key results include the following. (i) We identified two main states of the photosynthetic apparatus: a Ci-limited state and a light-limited state. (ii) We discovered nine alternative electron flow pathways that assist the photosynthetic linear electron flow in optimizing the photosynthesis performance. (iii) A high degree of cooperativity between alternative pathways was found to be critical for optimal autotrophic metabolism. Although pathways with high photosynthetic yield exist for optimizing growth under suboptimal light conditions, pathways with low photosynthetic yield guarantee optimal growth under excessive light or Ci limitation. (iv) Photorespiration was found to be essential for the optimal photosynthetic process, clarifying its role in high-light acclimation. Finally, (v) an extremely high photosynthetic robustness drives the optimal autotrophic metabolism at the expense of metabolic versatility and robustness. The results and modeling approach presented here may promote a better understanding of the photosynthetic process. They can also guide bioengineering projects toward optimal biofuel production in photosynthetic organisms.


Assuntos
Fotossíntese , Synechocystis/fisiologia , Biologia de Sistemas
3.
BMC Biol ; 12: 4, 2014 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-24461193

RESUMO

BACKGROUND: At the beginning of the transcription process, the RNA polymerase (RNAP) core enzyme requires a σ-factor to recognize the genomic location at which the process initiates. Although the crucial role of σ-factors has long been appreciated and characterized for many individual promoters, we do not yet have a genome-scale assessment of their function. RESULTS: Using multiple genome-scale measurements, we elucidated the network of σ-factor and promoter interactions in Escherichia coli. The reconstructed network includes 4,724 σ-factor-specific promoters corresponding to transcription units (TUs), representing an increase of more than 300% over what has been previously reported. The reconstructed network was used to investigate competition between alternative σ-factors (the σ70 and σ38 regulons), confirming the competition model of σ substitution and negative regulation by alternative σ-factors. Comparison with σ-factor binding in Klebsiella pneumoniae showed that transcriptional regulation of conserved genes in closely related species is unexpectedly divergent. CONCLUSIONS: The reconstructed network reveals the regulatory complexity of the promoter architecture in prokaryotic genomes, and opens a path to the direct determination of the systems biology of their transcriptional regulatory networks.


Assuntos
Escherichia coli/genética , Redes Reguladoras de Genes , Genoma Bacteriano/genética , Fator sigma/química , Fator sigma/metabolismo , RNA Polimerases Dirigidas por DNA/metabolismo , Bases de Dados Genéticas , Holoenzimas/metabolismo , Regiões Promotoras Genéticas , Ligação Proteica , Regulon/genética , Sítio de Iniciação de Transcrição , Transcrição Gênica
4.
Am J Nephrol ; 40(1): 29-35, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24993974

RESUMO

BACKGROUND: The association between membranous nephropathy (MN) and cancer has been well documented. However, the true prevalence and characteristics of cancer associated with MN have not been well described. METHODS: A systematic review and meta-analysis of cohort studies was conducted to summarize the prevalence of cancer-associated MN as well as patient characteristics and types of cancer in this population. We used a random-effects meta-analysis model to estimate the prevalence of cancer. RESULTS: We included 6 studies (n = 785). The estimated prevalence of cancer was 10.0% (95% CI, 6.1-14.6). The mean age of MN patients with cancer was 67 ± 7 years. The diagnosis of cancer preceded the diagnosis of MN in 20 ± 6.8%. Lung cancer was the most common type of tumor, accounting for 22 cases (26%), followed by prostate cancer (13 cases, 15%), hematologic malignancies (12 cases, 14%), colorectal cancer (9 cases, 11%), breast cancer (6 cases, 7%), and stomach and esophageal cancer (5 cases, 6%). CONCLUSION: The estimated prevalence of cancer in patients with MN is 10% (95% CI, 6.1-14.6). The vast majority of tumors associated with MN are lung and prostate cancer. Hematologic malignancies should also be considered as one of the potential cancers associated with MN. Our study was based on a largely Caucasian population; therefore, the findings might not be applicable to other populations.


Assuntos
Glomerulonefrite Membranosa/epidemiologia , Neoplasias/epidemiologia , Idoso , Neoplasias da Mama/epidemiologia , Neoplasias Colorretais/epidemiologia , Comorbidade , Neoplasias Esofágicas/epidemiologia , Feminino , Neoplasias Hematológicas/epidemiologia , Humanos , Neoplasias Pulmonares/epidemiologia , Masculino , Pessoa de Meia-Idade , Prevalência , Neoplasias da Próstata/epidemiologia , Neoplasias Gástricas/epidemiologia
5.
Respirology ; 19(7): 993-8, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25138430

RESUMO

A possible causal relationship between sarcoidosis and malignancy has been the subject of debates for decades. To better understand this association, we conducted a systematic review and meta-analysis of cohort studies that reported relative risk, hazard ratio or standardized incidence ratio with 95% confidence interval (CI) comparing the incidence of malignancy in patients with sarcoidosis versus non-sarcoidosis participants. Pooled risk ratios (RR) and 95% CI were calculated using a random-effect, generic inverse variance methodology. Five studies were identified and included in our data analyses. The pooled RR of malignancy in patients with sarcoidosis was 1.21 (95% CI: 1.04-1.40). However, when we performed a sensitivity analysis that included only studies that compared the incidence of malignancy after the first year of the diagnosis of sarcoidosis with the incidence of malignancy after the first year of index date for non-sarcoidosis controls, the pooled risk ratio decreased and did not reach statistical significance (RR 1.13, 95% CI: 0.97-1.32). Furthermore, analysis for publication bias has suggested that publication bias in favour of positive studies may be present. In conclusion, after accounting for possible detection bias and publication bias, there does not appear be a significant association between sarcoidosis and malignancy.


Assuntos
Neoplasias/epidemiologia , Sarcoidose/complicações , Humanos , Incidência , Razão de Chances
6.
PLoS Genet ; 6(11): e1001186, 2010 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-21079674

RESUMO

Bacterial survival requires adaptation to different environmental perturbations such as exposure to antibiotics, changes in temperature or oxygen levels, DNA damage, and alternative nutrient sources. During adaptation, bacteria often develop beneficial mutations that confer increased fitness in the new environment. Adaptation to the loss of a major non-essential gene product that cripples growth, however, has not been studied at the whole-genome level. We investigated the ability of Escherichia coli K-12 MG1655 to overcome the loss of phosphoglucose isomerase (pgi) by adaptively evolving ten replicates of E. coli lacking pgi for 50 days in glucose M9 minimal medium and by characterizing endpoint clones through whole-genome re-sequencing and phenotype profiling. We found that 1) the growth rates for all ten endpoint clones increased approximately 3-fold over the 50-day period; 2) two to five mutations arose during adaptation, most frequently in the NADH/NADPH transhydrogenases udhA and pntAB and in the stress-associated sigma factor rpoS; and 3) despite similar growth rates, at least three distinct endpoint phenotypes developed as defined by different rates of acetate and formate secretion. These results demonstrate that E. coli can adapt to the loss of a major metabolic gene product with only a handful of mutations and that adaptation can result in multiple, alternative phenotypes.


Assuntos
Adaptação Fisiológica/genética , Proteínas de Escherichia coli/genética , Escherichia coli/crescimento & desenvolvimento , Escherichia coli/genética , Deleção de Genes , Genes Bacterianos/genética , Glucose-6-Fosfato Isomerase/genética , Redes e Vias Metabólicas/genética , Acetatos/metabolismo , Proteínas de Bactérias/genética , Células Clonais , Epistasia Genética , Escherichia coli/enzimologia , Técnicas de Introdução de Genes , Glucose/metabolismo , Prófagos/metabolismo , Análise de Sequência de DNA , Fator sigma/genética
7.
Proc Natl Acad Sci U S A ; 107(47): 20500-5, 2010 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-21057108

RESUMO

Specific small deletions within the rpoC gene encoding the ß'-subunit of RNA polymerase (RNAP) are found repeatedly after adaptation of Escherichia coli K-12 MG1655 to growth in minimal media. Here we present a multiscale analysis of these mutations. At the physiological level, the mutants grow 60% faster than the parent strain and convert the carbon source 15-35% more efficiently to biomass, but grow about 30% slower than the parent strain in rich medium. At the molecular level, the kinetic parameters of the mutated RNAP were found to be altered, resulting in a 4- to 30-fold decrease in open complex longevity at an rRNA promoter and a ∼10-fold decrease in transcriptional pausing, with consequent increase in transcript elongation rate. At a genome-scale, systems biology level, gene expression changes between the parent strain and adapted RNAP mutants reveal large-scale systematic transcriptional changes that influence specific cellular processes, including strong down-regulation of motility, acid resistance, fimbria, and curlin genes. RNAP genome-binding maps reveal redistribution of RNAP that may facilitate relief of a metabolic bottleneck to growth. These findings suggest that reprogramming the kinetic parameters of RNAP through specific mutations allows regulatory adaptation for optimal growth in new environments.


Assuntos
Adaptação Fisiológica/genética , RNA Polimerases Dirigidas por DNA/genética , Proteínas de Escherichia coli/genética , Escherichia coli/enzimologia , Escherichia coli/crescimento & desenvolvimento , Evolução Molecular , Sequência de Bases , Imunoprecipitação da Cromatina , Meios de Cultura/química , Primers do DNA/genética , Perfilação da Expressão Gênica , Técnicas de Inativação de Genes , Cinética , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Análise Serial de Proteínas , Análise de Sequência de DNA , Deleção de Sequência/genética , Transcrição Gênica/fisiologia
8.
Proc Natl Acad Sci U S A ; 105(49): 19462-7, 2008 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-19052235

RESUMO

Broad-acting transcription factors (TFs) in bacteria form regulons. Here, we present a 4-step method to fully reconstruct the leucine-responsive protein (Lrp) regulon in Escherichia coli K-12 MG 1655 that regulates nitrogen metabolism. Step 1 is composed of obtaining high-resolution ChIP-chip data for Lrp, the RNA polymerase and expression profiles under multiple environmental conditions. We identified 138 unique and reproducible Lrp-binding regions and classified their binding state under different conditions. In the second step, the analysis of these data revealed 6 distinct regulatory modes for individual ORFs. In the third step, we used the functional assignment of the regulated ORFs to reconstruct 4 types of regulatory network motifs around the metabolites that are affected by the corresponding gene products. In the fourth step, we determined how leucine, as a signaling molecule, shifts the regulatory motifs for particular metabolites. The physiological structure that emerges shows the regulatory motifs for different amino acid fall into the traditional classification of amino acid families, thus elucidating the structure and physiological functions of the Lrp-regulon. The same procedure can be applied to other broad-acting TFs, opening the way to full bottom-up reconstruction of the transcriptional regulatory network in bacterial cells.


Assuntos
Proteínas de Escherichia coli/genética , Escherichia coli/genética , Regulação Bacteriana da Expressão Gênica , Redes Reguladoras de Genes , Genoma Bacteriano , Proteína Reguladora de Resposta a Leucina/genética , Escherichia coli/metabolismo , Proteínas de Escherichia coli/metabolismo , Retroalimentação Fisiológica , Genômica , Leucina/farmacocinética , Proteína Reguladora de Resposta a Leucina/metabolismo , Nitrogênio/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , RNA Bacteriano/genética , Transcrição Gênica
9.
Geogr Anal ; 53(2): 355-376, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34219795

RESUMO

The interlocking world city network model and other office location approaches (OLAs) have become the most widely used empirical models of the world city network (WCN). Despite numerous methodological improvements, they continue to rely on a legacy of using data on office locations of firms to indirectly estimate intercity business flows. To advance the dialogue about how to improve on existing empirical models of the WCN, we examine the content, construct and structural validity of OLAs. We analyze the link between the theoretical construct of intercity business flows and network projections obtained from office location data and uncover evidence that calls into question the validity of OLAs as empirical models of the WCN. In the spirit of no deconstruction without reconstruction, we then develop an alternative empirical model of the WCN, based on directly observable relational ties among APS firms, which are formed through co-production of complex services. We call this the inter-organizational project approach (IOPA). We argue for IOPA's construct validity as an empirical model of the WCN and offer empirical evidence for its structural validity. We demonstrate it using a global sample of 161,114 investment bank syndicates in the 2000-2015 period.

10.
Nature ; 429(6987): 92-6, 2004 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-15129285

RESUMO

The flood of high-throughput biological data has led to the expectation that computational (or in silico) models can be used to direct biological discovery, enabling biologists to reconcile heterogeneous data types, find inconsistencies and systematically generate hypotheses. Such a process is fundamentally iterative, where each iteration involves making model predictions, obtaining experimental data, reconciling the predicted outcomes with experimental ones, and using discrepancies to update the in silico model. Here we have reconstructed, on the basis of information derived from literature and databases, the first integrated genome-scale computational model of a transcriptional regulatory and metabolic network. The model accounts for 1,010 genes in Escherichia coli, including 104 regulatory genes whose products together with other stimuli regulate the expression of 479 of the 906 genes in the reconstructed metabolic network. This model is able not only to predict the outcomes of high-throughput growth phenotyping and gene expression experiments, but also to indicate knowledge gaps and identify previously unknown components and interactions in the regulatory and metabolic networks. We find that a systems biology approach that combines genome-scale experimentation and computation can systematically generate hypotheses on the basis of disparate data sources.


Assuntos
Biologia Computacional , Simulação por Computador , Escherichia coli/genética , Escherichia coli/metabolismo , Aerobiose/genética , Anaerobiose/genética , Escherichia coli/crescimento & desenvolvimento , Perfilação da Expressão Gênica , Genes Bacterianos/genética , Modelos Biológicos , Fenótipo
11.
Methods Mol Biol ; 439: 131-45, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18370100

RESUMO

Interactions between cis-acting elements and proteins play a key role in transcriptional regulation of all known organisms. To better understand these interactions, researchers developed a method that couples chromatin immunoprecipitation with microarrays (also known as ChIP-chip), which is capable of providing a whole-genome map of protein-DNA interactions. This versatile and high-throughput strategy is initiated by formaldehyde-mediated cross-linking of DNA and proteins, followed by cell lysis, DNA fragmentation, and immunopurification. The immunoprecipitated DNA fragments are then purified from the proteins by reverse-cross-linking followed by amplification, labeling, and hybridization to a whole-genome tiling microarray against a reference sample. The enriched signals obtained from the microarray then are normalized by the reference sample and used to generate the whole-genome map of protein-DNA interactions. The protocol described here has been used for discovering the genomewide distribution of RNA polymerase and several transcription factors of Escherichia coli.


Assuntos
Imunoprecipitação da Cromatina , Genoma , Análise de Sequência com Séries de Oligonucleotídeos , Sequência de Bases , Primers do DNA , Ligação Proteica
12.
Biotechniques ; 40(1): 67-72, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16454042

RESUMO

Biological discovery in the postgenomic era requires a systematic and high-throughput experimental approach. To this end, a versatile PCR-based tandem epitope tagging system is described, which inserts a tandem epitope coding sequence into any desired position of the Escherichia coli chromosome. Template plasmids were constructed that carry tandem copies of the epitope encoding sequence, Flp recombinase target (FRT) sites, and antibiotic resistance genes. The linear DNA fragment, amplified from the template plasmid with extensions homologous to the end of the target gene and part of its downstream region, was transformed into E. coli K-12 MG1655 harboring the bacteriophage gamma Red recombination system. The antibiotic resistance gene was then removed from the inserted heterologous PCR fragment using Flp recombinase. This epitope tagging system was applied to global transcription factors of E. coli to obtain proteins fused with tandem c-myc epitope tags. The tandem myc epitope-fused transcription factors were successfully detected by Western blot analysis and chromatin immunoprecipitation with increased detection sensitivity and higher yield. Higher copy numbers of the epitope molecule allowed the use of more stringent experimental conditions to increase the signal-to-noise ratio in subsequent experimental applications. Furthermore, judging from the measurement of gene expression using reverse transcription PCR (RT-PCR), the epitope-fused transcription factors retained their normal function for gene regulation in vivo.


Assuntos
Escherichia coli/genética , Reação em Cadeia da Polimerase/métodos , Engenharia de Proteínas/métodos , Proteínas Recombinantes de Fusão/química , Western Blotting , Imunoprecipitação da Cromatina , Epitopos/genética , Genes myc/genética , Genômica/métodos , Proteínas Recombinantes de Fusão/análise , Proteínas Recombinantes de Fusão/isolamento & purificação , Sequências de Repetição em Tandem , Fatores de Transcrição/genética
13.
Arch Intern Med ; 164(8): 885-91, 2004 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-15111375

RESUMO

BACKGROUND: In older women and men, greater intakes of dietary calcium, potassium, and total fluid reduce the risk of kidney stone formation, while supplemental calcium, sodium, animal protein, and sucrose may increase the risk. Recently, phytate has been suggested to play a role in stone formation. To our knowledge, no prospective information on the role of dietary factors and risk of kidney stone formation is available in younger women. METHODS: We prospectively examined, during an 8-year period, the association between dietary factors and the risk of incident symptomatic kidney stones among 96 245 female participants in the Nurses' Health Study II; the participants were aged 27 to 44 years and had no history of kidney stones. Self-administered food frequency questionnaires were used to assess diet in 1991 and 1995. The main outcome measure was an incident symptomatic kidney stone. Cox proportional hazards regression models were used to adjust simultaneously for various risk factors. RESULTS: We documented 1223 incident symptomatic kidney stones during 685 973 person-years of follow-up. After adjusting for relevant risk factors, a higher dietary calcium intake was associated with a reduced risk of kidney stones (P =.007 for trend). The multivariate relative risk among women in the highest quintile of intake of dietary calcium compared with women in the lowest quintile was 0.73 (95% confidence interval, 0.59-0.90). Supplemental calcium intake was not associated with risk of stone formation. Phytate intake was associated with a reduced risk of stone formation. Compared with women in the lowest quintile of phytate intake, the relative risk for those in the highest quintile was 0.63 (95% confidence interval, 0.51-0.78). Other dietary factors showed the following relative risks (95% confidence intervals) among women in the highest quintile of intake compared with those in the lowest quintile: animal protein, 0.84 (0.68-1.04); fluid, 0.68 (0.56-0.83); and sucrose, 1.31 (1.07-1.60). The intakes of sodium, potassium, and magnesium were not independently associated with risk after adjusting for other dietary factors. CONCLUSIONS: A higher intake of dietary calcium decreases the risk of kidney stone formation in younger women, but supplemental calcium is not associated with risk. This study also suggests that some dietary risk factors may differ by age and sex. Finally, dietary phytate may be a new, important, and safe addition to our options for stone prevention.


Assuntos
Dieta , Cálculos Renais/epidemiologia , Adulto , Cálcio da Dieta/farmacologia , Proteínas Alimentares , Feminino , Humanos , Ácido Fítico/farmacologia , Modelos de Riscos Proporcionais , Estudos Prospectivos
14.
Arch Intern Med ; 164(14): 1519-24, 2004 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-15277282

RESUMO

BACKGROUND: Analgesics are commonly used and may impair kidney function. However, limited prospective information is available on the long-term effects of aspirin, other nonsteroidal anti-inflammatory drugs (NSAIDs), and acetaminophen on renal function. METHODS: A total of 1697 women participating in the Nurses' Health Study provided information on a mailed questionnaire in 1999 about lifetime use of acetaminophen, aspirin, and NSAIDs and provided blood samples in 1989 and 2000. The main outcome was change in estimated glomerular filtration rate (GFR) in 11 years. Multivariate logistic regression was used to determine the odds of developing the outcome according to lifetime analgesic intake. RESULTS: The mean +/- SD estimated GFR decreased from 88 +/- 17 to 79 +/- 17 mL/min per 1.73 m(2). There were no substantial differences in the unadjusted or estimated GFR levels among the categories of lifetime intake for the 3 analgesic groups at baseline or after 11 years. Acetaminophen use was associated with an increased risk of a GFR decline of at least 30 mL/min per 1.73 m(2) (P trend =.01) and a GFR decline of 30% or greater (P trend<.001), but aspirin and NSAID use were not. Compared with women consuming less than 100 g of acetaminophen, multivariate-adjusted odds ratio (95% confidence intervals) for a decline in GFR of at least 30 mL/min per 1.73 m(2) for women consuming more than 3000 g was 2.04 (1.28-3.24). CONCLUSIONS: Higher lifetime use of aspirin and NSAIDs is not associated with renal function decline, but high acetaminophen use may increase the risk of loss of renal function. The absolute risk of renal function decline due to even high lifetime analgesic intake seems to be modest.


Assuntos
Acetaminofen/efeitos adversos , Analgésicos não Narcóticos/agonistas , Anti-Inflamatórios não Esteroides/efeitos adversos , Aspirina/efeitos adversos , Taxa de Filtração Glomerular/efeitos dos fármacos , Acetaminofen/administração & dosagem , Adulto , Analgésicos não Narcóticos/administração & dosagem , Anti-Inflamatórios não Esteroides/administração & dosagem , Aspirina/administração & dosagem , Feminino , Humanos , Pessoa de Meia-Idade , Análise Multivariada , Inquéritos e Questionários
15.
Ann Intern Med ; 138(6): 460-7, 2003 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-12639078

RESUMO

BACKGROUND: In individuals with moderate to severe renal insufficiency, low protein intake may slow renal function decline. However, the long-term impact of protein intake on renal function in persons with normal renal function or mild renal insufficiency is unknown. OBJECTIVE: To determine whether protein intake influences the rate of renal function change in women over an 11-year period. DESIGN: Prospective cohort study. SETTING: Nurses' Health Study. PARTICIPANTS: 1624 women enrolled in the Nurses' Health Study who were 42 to 68 years of age in 1989 and gave blood samples in 1989 and 2000. Ninety-eight percent of women were white, and 1% were African American. MEASUREMENTS: Protein intake was measured in 1990 and 1994 by using a semi-quantitative food-frequency questionnaire. Creatinine concentration was used to estimate glomerular filtration rate (GFR) and creatinine clearance. RESULTS: In multivariate linear regression analyses, high protein intake was not significantly associated with change in estimated GFR in women with normal renal function (defined as an estimated GFR > or = 80 mL/min per 1.73 m2). Change in estimated GFR in this subgroup over the 11-year period was 0.25 mL/min per 1.73 m2 (95% CI, -0.78 to 1.28 mL/min per 1.73 m2) per 10-g increase in protein intake; the change in estimated GFR was 1.14 mL/min per 1.73 m2 (CI, -3.63 to 5.92 mL/min per 1.73 m2) after measurement-error adjustment for protein intake. In women with mild renal insufficiency (defined as an estimated GFR > 55 mL/min per 1.73 m2 but <80 mL/min per 1.73 m2), protein intake was significantly associated with a change in estimated GFR of -1.69 mL/min per 1.73 m2 (CI, -2.93 to -0.45 mL/min per 1.73 m2) per 10-g increase in protein intake. After measurement-error adjustment, the change in estimated GFR was -7.72 mL/min per 1.73 m2 (CI, -15.52 to 0.08 mL/min per 1.73 m2) per 10-g increase in protein intake, an association of borderline statistical significance. High intake of nondairy animal protein in women with mild renal insufficiency was associated with a significantly greater change in estimated GFR (-1.21 mL/min per 1.73 m2 [CI, -2.34 to -0.33 mL/min per 1.73 m2] per 10-g increase in nondairy animal protein intake). CONCLUSIONS: High protein intake was not associated with renal function decline in women with normal renal function. However, high total protein intake, particularly high intake of nondairy animal protein, may accelerate renal function decline in women with mild renal insufficiency.


Assuntos
Proteínas Alimentares/administração & dosagem , Rim/fisiopatologia , Insuficiência Renal/fisiopatologia , Adulto , Idoso , Creatinina/metabolismo , Feminino , Taxa de Filtração Glomerular , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos , Análise de Regressão , Insuficiência Renal/dietoterapia , Inquéritos e Questionários
16.
Ann Intern Med ; 140(9): 714-20, 2004 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-15126255

RESUMO

BACKGROUND: Although pharmacotherapy is critical to the medical care of older patients, medications can have considerable toxicity in this age group. To date, research has focused on inappropriate prescribing and policy efforts have aimed at access, but no comprehensive measurement of the quality of pharmacologic management using explicit criteria has been performed. OBJECTIVE: To evaluate the broad range of pharmacologic care processes for vulnerable older patients. DESIGN: Observational cohort study. SETTING: 2 managed care organizations enrolling older persons. PATIENTS: Community-dwelling high-risk patients 65 years of age or older continuously enrolled in the managed care organizations from 1 July 1998 to 31 July 1999. MEASUREMENTS: Patients' receipt of care as specified in 43 quality indicators covering 4 domains of pharmacologic care: 1) prescribing indicated medications; 2) avoiding inappropriate medications; 3) education, continuity, and documentation; and 4) medication monitoring. RESULTS: Of 475 vulnerable older patients, 372 (78%) consented to participate and had medical records that could be abstracted. The percentage of appropriate pharmacologic management ranged from 10% for documentation of risks of nonsteroidal anti-inflammatory drugs to 100% for avoiding short-acting calcium-channel blockers in patients with heart failure and avoiding beta-blockers in patients with asthma. Pass rates for quality indicators in the "avoiding inappropriate medications" domain (97% [95% CI, 96% to 98%]) were significantly higher than pass rates for "prescribing indicated medications" (50% [CI, 45% to 55%]); "education, continuity, and documentation" (81% [CI, 79% to 84%]); and "medication monitoring" (64% [CI, 60% to 68%]). LIMITATIONS: Fewer than 10 patients were eligible for many of the quality indicators measured, and the generalizability of these findings in 2 managed care organizations to the general geriatric population is uncertain. CONCLUSIONS: Failures to prescribe indicated medications, monitor medications appropriately, document necessary information, educate patients, and maintain continuity are more common prescribing problems than use of inappropriate drugs in older patients.


Assuntos
Idoso , Prescrições de Medicamentos/normas , Tratamento Farmacológico/normas , Indicadores de Qualidade em Assistência à Saúde , Idoso de 80 Anos ou mais , Continuidade da Assistência ao Paciente/normas , Documentação , Monitoramento de Medicamentos/normas , Feminino , Humanos , Masculino , Programas de Assistência Gerenciada/normas , Educação de Pacientes como Assunto
17.
PLoS One ; 10(7): e0132970, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26151753

RESUMO

BACKGROUND: HMG CoA reductase inhibitors (statins) are known to prevent cardiovascular disease and improve lipid profiles. However, the effects of statins on renal outcomes, including decline in estimated glomerular filtration rate (eGFR) and proteinuria in patients with chronic kidney disease (CKD), are controversial. This meta-analysis evaluated the impact of statins on renal outcomes in patients with CKD. MATERIALS AND METHODS: We comprehensively searched the databases of MEDLINE, EMBASE, and Cochrane Databases. The inclusion criteria were published RCT and cohort studies comparing statin therapy to placebo or active controls in patients with CKD (eGFR <60 ml/min/1.73 m(2)) not requiring dialysis. The primary outcome was the differences in the change of eGFR. We also examined change of protein concentration in urine as a secondary outcome. A meta-analysis comparing statin and its control groups and a subgroup analysis examining intensity of statin were performed. RESULTS: From 142 full-text articles, 10 studies were included in the meta-analysis. Overall, there was a significant difference in rate of eGFR change per year favoring statin group (mean difference (MD) = 0.10 ml/min/1.73 m(2), 95% CI: 0.09 to 0.12). In our subgroup analysis, those who received high-intensity statins had a significant difference in eGFR with a MD of 3.35 (95% CI: 0.91 to 5.79) ml/min/1.73 m(2) compared to control. No significant change in eGFR was found with moderate- and low-intensity statin therapy. Compared with the control group, the statin group did not have a difference in reduction of proteinuria with MD in change of proteinuria of 0.19 gm/day (95% CI: -0.02 to 0.40). CONCLUSION: Overall, there was a difference in change of eGFR between the statin and control group. High-intensity statins were found to improve a decline in eGFR in population with CKD not requiring dialysis compared with control, but moderate- and low-intensity statins were not. Statins were not found to decrease proteinuria in patients with CKD.


Assuntos
Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Rim/patologia , Insuficiência Renal Crônica/tratamento farmacológico , Estudos de Casos e Controles , Feminino , Taxa de Filtração Glomerular/efeitos dos fármacos , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Rim/efeitos dos fármacos , Rim/fisiopatologia , Masculino , Pessoa de Meia-Idade , Viés de Publicação , Análise de Regressão , Insuficiência Renal Crônica/fisiopatologia , Resultado do Tratamento
19.
Am J Cardiol ; 94(4): 415-20, 2004 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-15325921

RESUMO

Thrombolytic therapy decreases the mortality rate in patients with acute myocardial infarction (AMI), and the timing of thrombolysis has proved to be critical for decreasing the short-term mortality rate. Much less is known about the longer term consequences of delays in thrombolysis, particularly for outcomes other than the mortality rate. We assessed the effect of time to thrombolysis and other clinical predictors on cardiac functional status 6 months after AMI. We used InTIME II, a multicenter trial, to test the efficacy of alteplase and lanoteplase. This component of the trial was conducted in 147 North American centers. Patients were > or =18 years of age with ST-elevated AMI. Functional status was measured by the Duke Activity Status Index, which was administered 6 months after AMI. After multivariate adjustment for baseline characteristics, delay in presentation to hospital and delay in initiation of thrombolysis were significantly and independently associated with decreased cardiac functional status 6 months later. Each additional hour from symptom onset to hospital presentation was associated with a 16% increase (95% confidence interval 3% to 31%) in the likelihood of functional impairment (Duke Activity Status Index score < or =30). In addition, each additional delay of 1 hour from hospital presentation to thrombolysis independently increased the probability of functional impairment by 38% (12% to 71%). Thus, in patients with AMI, earlier presentation to the hospital and more rapid initiation of thrombolysis could prevent significant decreases in functional status months after the initial infarct.


Assuntos
Atividades Cotidianas/classificação , Fibrinolíticos/administração & dosagem , Infarto do Miocárdio/tratamento farmacológico , Terapia Trombolítica/estatística & dados numéricos , Ativador de Plasminogênio Tecidual/administração & dosagem , Idoso , Avaliação da Deficiência , Feminino , Fibrinolíticos/efeitos adversos , Seguimentos , Humanos , Funções Verossimilhança , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/mortalidade , Admissão do Paciente/estatística & dados numéricos , Estudos Prospectivos , Risco , Análise de Sobrevida , Fatores de Tempo , Ativador de Plasminogênio Tecidual/efeitos adversos , Estados Unidos
20.
Am J Kidney Dis ; 41(3): 588-95, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12612982

RESUMO

BACKGROUND: High-normal blood pressure (BP) is associated with increased cardiovascular risk compared with optimal BP, but no study has specifically examined the association between high-normal BP and microalbuminuria, an established predictor of future cardiovascular events. METHODS: This was a cross-sectional study of normotensive (systolic BP [SBP] < 140 mm Hg, diastolic BP [DBP] < 90 mm Hg) individuals without diabetes with no hypertension history enrolled in the Third National Health and Nutrition Examination Survey. BP was categorized as high normal (SBP, 130 to 139 mm Hg or DBP, 85 to 89 mm Hg), normal (SBP, 120 to 129 mm Hg or DBP, 80 to 84 mm Hg), and optimal (SBP < 120 mm Hg and DBP < 80 mm Hg). We also separately examined SBP, DBP, mean arterial pressure (MAP), and pulse pressure. Microalbuminuria was defined using sex-specific cutoff values (urine albumin-creatinine ratio > or = 17 and < or = 250 microg/mg [> or =1.0 and < or =28 mg/mmol] for men and > or = 25 and < or = 355 microg/mg for women [> or =3 and < or =40 mg/mmol]). We used multivariate logistic regression to analyze the association between different BP measurements and microalbuminuria. RESULTS: Compared with optimal BP, high-normal BP was significantly associated with increased odds of microalbuminuria (odds ratio [OR], 2.13; 95% confidence interval [CI], 1.51 to 3.01). Similarly, MAP (OR, 1.41; 95% CI, 1.15 to 1.74 per 10-mm Hg increment), SBP (OR, 1.27; 95% CI, 1.09 to 1.48 per 10-mm Hg increment), and DBP (OR, 1.29; 95% CI, 1.06 to 1.57 per 10-mm Hg increment) were significantly associated with microalbuminuria. CONCLUSION: High-normal BP is significantly associated with microalbuminuria compared with optimal BP and may be a biomarker of the increased cardiovascular risk observed in this population.


Assuntos
Albuminúria/epidemiologia , Pressão Sanguínea/fisiologia , Hipertensão/epidemiologia , Hipertensão/urina , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Diástole/fisiologia , Etnicidade/estatística & dados numéricos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Inquéritos Nutricionais , Grupos Raciais , Caracteres Sexuais , Sístole/fisiologia
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