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1.
Environ Pollut ; 195: 336-43, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25028265

RESUMO

This study analyzes the potential to reduce air pollutants while achieving the 2 °C global temperature change limit target above pre-industrial levels, by using the bottom-up optimization model, AIM/Enduse[Global]. This study focuses on; 1) estimating mitigation potentials and costs for achieving 2 °C, 2.5 °C, and 3 °C target scenarios, 2) assessing co-benefits of reducing air pollutants such as NOx, SO2, BC, PM, and 3) analyzing features of sectoral attributions in Annex I and Non-Annex I groups of countries. The carbon tax scenario at 50 US$/tCO2-eq in 2050 can reduce GHG emissions more than the 3 °C target scenario, but a higher carbon price around 400 US$/tCO2-eq in 2050 is required to achieve the 2 °C target scenario. However, there is also a co-benefit of large reduction potential of air pollutants, in the range of 60-80% reductions in 2050 from the reference scenario while achieving the 2 °C target.


Assuntos
Poluentes Atmosféricos/análise , Mudança Climática , Recuperação e Remediação Ambiental/métodos , Política Ambiental , Recuperação e Remediação Ambiental/economia , Modelos Teóricos , Temperatura
2.
J Biochem ; 154(6): 513-9, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23997091

RESUMO

AML1/RUNX1 is an essential transcription factor involved in the differentiation of hematopoietic cells. AML1 binds to the Runt-binding double-stranded DNA element (RDE) of target genes through its N-terminal Runt domain. In a previous study, we obtained RNA aptamers against the AML1 Runt domain by systematic evolution of ligands by exponential enrichment and revealed that RNA aptamers exhibit higher affinity for the Runt domain than that for RDE and possess the 5'-GCGMGNN-3' and 5'-N'N'CCAC-3' conserved motif (M: A or C; N and N' form Watson-Crick base pairs) that is important for Runt domain binding. In this study, to understand the structural basis of recognition of the Runt domain by the aptamer motif, the solution structure of a 22-mer RNA was determined using nuclear magnetic resonance. The motif contains the AH(+)-C mismatch and base triple and adopts an unusual backbone structure. Structural analysis of the aptamer motif indicated that the aptamer binds to the Runt domain by mimicking the RDE sequence and structure. Our data should enhance the understanding of the structural basis of DNA mimicry by RNA molecules.


Assuntos
Aptâmeros de Nucleotídeos/química , Subunidade alfa 2 de Fator de Ligação ao Core/antagonistas & inibidores , Subunidade alfa 2 de Fator de Ligação ao Core/química , DNA/química , Mimetismo Molecular , Motivos de Nucleotídeos , Humanos , Ressonância Magnética Nuclear Biomolecular , Estrutura Terciária de Proteína , Soluções
3.
J Atheroscler Thromb ; 19(4): 385-96, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22240906

RESUMO

AIM: The post-challenge glucose (PCG) level has been suggested to be superior to the fasting blood glucose (FG) level for predicting the risk of future cardiovascular disease (CVD); however, the extent of its superiority has not been consistently shown among previous cohort studies. Therefore, we conducted a meta-analysis to summarize the quantitative association of FG and PCG with CVD risk and compared the strengths of the two associations. METHOD: Electronic literature searches using MEDLINE and EMBASE with an additional manual search were conducted for prospective observational studies of the association of FG and PCG with CVD risk. Studies were included if they were prospective studies in which the relative risk (RR) of CVD per 1 standard deviation increase in both FG and PCG could be estimated. Pooled relative risks for the incremental increase were calculated as RR(FG) and RR(PCG) using a bivariate random-effects model. RESULT: Data were obtained from 14 eligible studies that included 70,889 participants and 2,927 cases. The pooled RR(FG) and RR(PCG) (95% confidence interval) were, respectively, 1.15 (1.06 to 1.26) and 1.24 (1.12 to 1.36); the difference was significant (P =0.001). The association of PCG with CVD risk was stronger in studies that targeted participants with a baseline mean FG < 100 mg/dl (P < 0.001) or mean age ≥ 55 years (P =0.004). CONCLUSIONS: Overall, the association of PCG with CVD risk was stronger than that of FG by approximately 50% on a log scale. Measuring PCG is especially important in populations with relatively low FG levels or in the elderly, although it is often burdensome in routine clinical practice.


Assuntos
Doenças Cardiovasculares/epidemiologia , Glucose/administração & dosagem , Humanos , Estudos Prospectivos , Fatores de Risco
4.
Lancet ; 378(9786): 147-55, 2011 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-21705064

RESUMO

BACKGROUND: The clinical relevance of the diagnostic criteria for prediabetes to prediction of progression to diabetes has been little studied. We aimed to compare the prevalence of prediabetes when assessed by the new glycated haemoglobin A(1c) (HbA(1c)) 5·7-6·4% criterion or by impaired fasting glucose, and assessed differences in progression rate to diabetes between these two criteria for prediabetes in a Japanese population. METHODS: Our longitudinal cohort study included 4670 men and 1571 women aged 24-82 years without diabetes at baseline (diabetes was defined as fasting plasma glucose ≥7·0 mmol/L, self-reported clinician-diagnosed diabetes, or HbA(1c) ≥6·5%) who attended Toranomon Hospital (Tokyo, Japan) for a routine health check between 1997 and 2003. Participants with a baseline diagnosis of prediabetes according to impaired fasting glucose (fasting plasma glucose 5·6-6·9 mmol/L) or HbA(1c) 5·7-6·4%, or both, were divided into four groups on the basis of baseline diagnosis of prediabetes. Rate of progression to diabetes was assessed annually. FINDINGS: Mean follow-up was 4·7 (SD 0·7) years. 412 (7%) of 6241 participants were diagnosed with prediabetes on the basis of the HbA(1c) 5·7-6·4% criterion. Screening by HbA(1c) alone missed 1270 (61%) of the 2092 prediabetic individuals diagnosed by a combination of impaired fasting glucose and HbA(1c) 5·7-6·4%. Overall cumulative probability of progression to diabetes did not differ significantly between participants with prediabetes discordantly diagnosed by either HbA(1c) or impaired fasting glucose alone (incidence was 7% for HbA(1c) alone [n=412 individuals and 30 incident cases] and 9% for impaired fasting glucose alone [n=1270, 108 cases]; log-rank test, p=0·3317). Multivariate-adjusted hazard ratios for incident diabetes were 6·16 (95% CI 4·33-8·77) for those diagnosed with prediabetes by impaired fasting glucose alone and 6·00 (3·76-9·56) for diagnosis by HbA(1c) alone, and were substantially increased to 31·9 (22·6-45·0) for diagnosis by both impaired fasting glucose and HbA(1c) compared with normoglycaemic individuals. INTERPRETATION: Diagnosis of prediabetes by both the new HbA(1c) criterion and impaired fasting glucose identified individuals with an increased risk of progression to diabetes. Although the new HbA(1c) criterion identified fewer individuals at high risk than did impaired fasting glucose, the predictive value for progression to diabetes assessed by HbA(1c) 5·7-6·4% was similar to that assessed by impaired fasting glucose alone. The two tests used together could efficiently target people who are most likely to develop diabetes and allow for early intervention. FUNDING: Japan Society for the Promotion of Science; Ministry of Health Labor and Welfare, Japan.


Assuntos
Glicemia/análise , Hemoglobinas Glicadas/análise , Estado Pré-Diabético/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Progressão da Doença , Feminino , Frequência Cardíaca , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Estado Pré-Diabético/epidemiologia , Prevalência , Curva ROC , Sensibilidade e Especificidade
5.
Nippon Ganka Gakkai Zasshi ; 115(4): 391-7, 2011 Apr.
Artigo em Japonês | MEDLINE | ID: mdl-21598609

RESUMO

BACKGROUND: There is an increasing interest in the relation between retinal artery abnormalities and cerebral small-vessel diseases (SVD), because retinal vessels share common properties with cerebral small vessels. We report a case of juvenile cerebrovascular disease presenting retinal vessel abnormalities, which clinically resembled cerebral autosomal dominant arteriopathy with stroke and ischemic leukoencephalopathy (CADASIL) but in which Notch3 gene mutations were not detected. CASE: A 42-year old woman was hospitalized at the department of Neurology in our hospital, complaining of headache and dysarthria. MRI showed bilateral spotted white matter lesions in the paraventricular area and the temporal lobe, and an ovoid lesion in the right corona radiata. Despite steroid pulse therapy, she developed right incomplete hemiparesis and new lesions were detected in the anterior temporal pole and external capsule. Her genetic analysis showed no mutations in the Notch 3 gene. Ophthalmological examination revealed arterial sheathing in the peripapillary region. Fluorescein angiography showed narrowing of the retinal arterioles and distinguished a peripheral vascular network. CONCLUSION: In this case, ophthalmological examination revealed retinal vessel abnormalities in a relatively young woman with no risk factors such as hypertention or artheriosclerosis, presenting recurrent subcortical strokes. This actual case indicates the association between retinal vessel abnormalities and cerebral SVDs.


Assuntos
Transtornos Cerebrovasculares/complicações , Doenças Retinianas/complicações , Vasos Retinianos , Adulto , CADASIL/diagnóstico , Transtornos Cerebrovasculares/diagnóstico , Diagnóstico Diferencial , Feminino , Humanos , Doenças Retinianas/diagnóstico
6.
Nihon Shokakibyo Gakkai Zasshi ; 104(12): 1766-71, 2007 Dec.
Artigo em Japonês | MEDLINE | ID: mdl-18057855

RESUMO

We report a resected case of small spindle cell carcinoma of the pancreas, In a Japanese 71-year-old woman with upper abdominal pain, a computed tomography (CT) showed a solid tumor 10 mm in diameter in the body of the pancreas. We perfomed distal pancreatectomy with splenectomy. Twenty months after the operation, the patient is alive without recurrence. Although the outcome of spindle cell carcinoma of the pancreas has been reported to be very poor, there may be hope of cure in the patients with small spindle cell carcinoma.


Assuntos
Carcinoma/cirurgia , Neoplasias Pancreáticas/cirurgia , Idoso , Feminino , Humanos , Pancreatectomia , Esplenectomia
7.
PLoS One ; 2(9): e905, 2007 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-17878940

RESUMO

Predicting RNA secondary structure is often the first step to determining the structure of RNA. Prediction approaches have historically avoided searching for pseudoknots because of the extreme combinatorial and time complexity of the problem. Yet neglecting pseudoknots limits the utility of such approaches. Here, an algorithm utilizing structure mapping and thermodynamics is introduced for RNA pseudoknot prediction that finds the minimum free energy and identifies information about the flexibility of the RNA. The heuristic approach takes advantage of the 5' to 3' folding direction of many biological RNA molecules and is consistent with the hierarchical folding hypothesis and the contact order model. Mapping methods are used to build and analyze the folded structure for pseudoknots and to add important 3D structural considerations. The program can predict some well known pseudoknot structures correctly. The results of this study suggest that many functional RNA sequences are optimized for proper folding. They also suggest directions we can proceed in the future to achieve even better results.


Assuntos
Modelos Moleculares , Conformação de Ácido Nucleico , RNA/química
8.
Artigo em Inglês | MEDLINE | ID: mdl-16541960

RESUMO

We are developing a program to calculate optimal RNA secondary structures. The model uses di-nucleotide pairing energies as with most traditional approaches. However, for long-range entropy interactions, the approach uses an entropy-loss model based on the accumulated sum of the entropy of bonding between each base-pair weighted inversely by the correlation of the RNA sequence (the Kuhn length). Stiff RNA forms very different structures from flexible RNA. The results demonstrate that the long-range folding is largely governed by this entropy and the Kuhn length.


Assuntos
Entropia , Modelos Químicos , RNA/química , Modelos Moleculares , Estrutura Molecular , Conformação de Ácido Nucleico
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