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1.
J Chem Inf Model ; 60(3): 1224-1234, 2020 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-32058720

RESUMO

Modern industrial lubricants are often blended with an assortment of chemical additives to improve the performance of the base stock. Machine learning-based predictive models allow fast and veracious derivation of material properties and facilitate novel and innovative material designs. In this study, we outline the design and training process of a general feed-forward artificial neural network that accurately predicts the dynamic viscosity of oil-based lubricant formulations. The network hyperparameters are systematically optimized by Bayesian optimization, and strongly correlated/collinear features are trimmed from the model. By harnessing domain knowledge in the selection of features, the quantitative structure-property relationship model is built with a relatively simple feature set and is versatile in predicting the dynamic viscosity of lubricant oils with and without enhancement by viscosity modifiers (VMs). Moreover, partial dependency, local-interpretable model-agnostic explanations, and Shapley values consistently show that the eccentricity index, Crippen MR, and Petitjean number are important predictors of viscosity. All in all, the neural model is reasonably accurate in predicting the dynamic viscosity of lubricant solvents and VM-enhanced lubricants with an R2 of 0.980 and 0.963, respectively.


Assuntos
Lubrificantes , Redes Neurais de Computação , Teorema de Bayes , Viscosidade
2.
J Food Sci Technol ; 57(3): 1150-1157, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32123436

RESUMO

The aim of the study was to solve the mystery why sulfur-containing amino acids such as methionine can perform as an antioxidant during frying and hypothesized the antioxidative mechanisms. The results of this study revealed that sulfur-containing amino acids such as methionine failed to show DPPH· scavenging activity at room temperature but had valuable antioxidant activity based on OSI test at heated temperature. NMR analysis proved that methionine formed an intermediate molecule, 3-(methylthio)propylamine via decarboxylation during pyrolysis at heated temperature which was responsible for its antioxidant activity as shown by the OSI results. The mechanisms showed the proposed antioxidant behavior of methionine at heated temperature: (1) At heated temperature, 3-(methylthio)propylamine is generated by decarboxylation and (2) The antioxidant activity of 3-(methylthio)propylamine might be ascribed to the cooperation of amino group and the methylsulf-hydryl group in 3-methylthiopropylamine. From the frying study, methionine showed about 50% lower antioxidant capacity when compared TBHQ (tert-butylhydroquinone) based on OSI study, however, it has unexpected superior antioxidant activity under frying conditions that was on par with TBHQ. In summary, sulfur-containing amino acids with excellent antioxidant abilities might be useful for the food processing industry as antioxidant additives to extend shelf-life of food or food products.

3.
Clin Radiol ; 72(12): 1002-1013, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29032802

RESUMO

Transarterial radioembolisation (TARE) has gained increasing acceptance as an additional/alternative locoregional treatment option for hepatocellular carcinoma, and colorectal hepatic metastases that present beyond potentially curative options. This is a catheter-based transarterial selective internal brachytherapy that involves injection of radioactive microspheres (usually Y-90) that are delivered selectively to the liver tumours. Owing to the combined radioactive and microembolic effect, the findings at follow-up imaging are significantly different from that seen with other transarterial treatment options. Considering increasing confidence among clinicians, refinement in techniques and increasing number of ongoing trials, TARE is expected to gain further acceptance and become an important tool in the armamentarium for the treatment of liver malignancies. So it is imperative that all radiologists involved in the management of liver malignancies are well versed with TARE to facilitate appropriate discussion at multidisciplinary meetings to direct further management. In this article, we provide a comprehensive review on various aspects of radioembolisation with Y-90 for hepatocellular carcinoma including the patient selection, treatment planning, radiation dosimetry and treatment, side effects, follow-up imaging and future direction.


Assuntos
Embolização Terapêutica/métodos , Radioisótopos de Ítrio/uso terapêutico , Carcinoma Hepatocelular , Humanos , Neoplasias Hepáticas , Microesferas
5.
J Food Sci Technol ; 54(12): 4035-4041, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29085146

RESUMO

Improvement in the frying performance of palmolein oil with NaturFORT™ TRLG 101 (TRLG 101) liquid in addition to tert-butyl hydroquinone (TBHQ) has been evaluated. Four treatment groups (Negative control, 200 ppm TBHQ, 200 ppm TBHQ + 400 ppm TRLG 101 liquid and 200 ppm TBHQ + 750 ppm TRLG 101 liquid) were added to RBD (Refined, Bleached and Deodorized) palm olein oil which was used to produce potato chips. Frying trials were conducted for 120th frying cycles. The oil samples were analyzed for peroxide value, free fatty acid, p-anisidine value, oxidative stability index, %total polar compounds and Chroma (C*) values after every 20 frying cycles. Potato chips were analyzed for Chroma (C*) values after every 20 frying cycles. The results of oxidative stability index, total polar compounds and p-anisidine value showed that the addition of NaturFORT™ TRLG 101 liquid at 750 ppm had showed significantly better performance followed by the addition of NaturFORT™ TRLG 101 liquid at 400 ppm. Thus, the addition of NaturFORT™ TRLG 101 liquid as on top of TBHQ contributes to the improvement in the frying performance of palm olein oil with subject to their dosage and this could be a better solution for frying industries which would like to get extra frying cycles for their products without encountering the regulatory hurdles posed by the limitations of using such additives.

6.
Proc Natl Acad Sci U S A ; 110(43): 17263-6, 2013 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-24101468

RESUMO

The recent discovery of iron ferropnictide superconductors has received intensive concern in connection with magnetically involved superconductors. Prominent features of ferropnictide superconductors are becoming apparent: the parent compounds exhibit an antiferromagnetic ordered spin density wave (SDW) state, the magnetic-phase transition is always accompanied by a crystal structural transition, and superconductivity can be induced by suppressing the SDW phase via either chemical doping or applied external pressure to the parent state. These features generated considerable interest in the interplay between magnetism and structure in chemically doped samples, showing crystal structure transitions always precede or coincide with magnetic transition. Pressure-tuned transition, on the other hand, would be more straightforward to superconducting mechanism studies because there are no disorder effects caused by chemical doping; however, remarkably little is known about the interplay in the parent compounds under controlled pressure due to the experimental challenge of in situ measuring both of magnetic and crystal structure evolution at high pressure and low temperatures. Here we show from combined synchrotron Mössbauer and X-ray diffraction at high pressures that the magnetic ordering surprisingly precedes the structural transition at high pressures in the parent compound BaFe2As2, in sharp contrast to the chemical-doping case. The results can be well understood in terms of the spin fluctuations in the emerging nematic phase before the long-range magnetic order that sheds light on understanding how the parent compound evolves from a SDW state to a superconducting phase, a key scientific inquiry of iron-based superconductors.


Assuntos
Arsênio/química , Bário/química , Condutividade Elétrica , Compostos Ferrosos/química , Ferro/química , Magnetismo , Cristalização , Transição de Fase , Pressão , Espectroscopia de Mossbauer , Síncrotrons , Temperatura , Difração de Raios X
7.
Infection ; 42(2): 343-50, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24277597

RESUMO

PURPOSE: Respiratory syncytial virus (RSV) is a common cause of lower respiratory tract infection in young children. However, there are limited data on severe RSV infection requiring pediatric intensive care unit (PICU) admission. This retrospective study described features of RSV-associated PICU admissions in Hong Kong and investigated factors for mortality and duration of PICU stay. METHODS: Children with laboratory-confirmed RSV infection and admitted to the PICUs of all eight government hospitals in Hong Kong between January 2009 and June 2011 were identified from computerized auditing systems and PICU databases. RSV in respiratory samples was detected by direct immunofluorescence and/or viral culture. The relationships between mortality and PICU duration and demographic and clinical factors were analyzed. RESULTS: A total of 118 (2.4 %) PICU admissions were identified among 4,912 RSV-positive pediatric cases in all hospitals. Sixty-five (55.6 %) patients were infants. PICU admissions were higher between October and March. Eight (6.8 %) patients died, but only two were infants. RSV-associated mortality was related to prior sick contact, presence of older siblings, neurodevelopmental conditions, chromosomal and genetic diseases, and bacterial co-infections, but none was significant following logistic regression analyses (odds ratio 9.36, 95 % confidence interval 0.91-96.03 for prior sick contact, p = 0.060). Chronic lung disease was the only risk factor for the duration of PICU admission (ß = 0.218, p = 0.017). CONCLUSIONS: The majority of RSV-infected children do not require PICU support. There is winter seasonality for RSV-associated PICU admission in Hong Kong. Prior sick contact is the only risk factor for RSV-associated mortality, whereas the presence of chronic lung disease is associated with longer PICU stay. The current risk-based approach of RSV prophylaxis may not be effective in reducing severe RSV infections.


Assuntos
Infecções por Vírus Respiratório Sincicial/epidemiologia , Vírus Sinciciais Respiratórios/isolamento & purificação , Infecções Respiratórias/epidemiologia , Pré-Escolar , Feminino , Hong Kong/epidemiologia , Hospitalização , Humanos , Lactente , Unidades de Terapia Intensiva Pediátrica , Masculino , Infecções por Vírus Respiratório Sincicial/microbiologia , Infecções por Vírus Respiratório Sincicial/mortalidade , Infecções Respiratórias/microbiologia , Infecções Respiratórias/mortalidade , Estudos Retrospectivos , Fatores de Risco
8.
Br Poult Sci ; 55(3): 398-402, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24783946

RESUMO

1. This study was designed to test the hypothesis that microemulsified carotenoid products show improved bioavailability over corresponding regular preparations, leading to greater yolk pigmentation at lower dosages. 2. The first trial was conducted using a maize-soya bean basal diet supplemented with either 0.25, 0.5, 0.75, 1.0 and 1.25 g/kg of microemulsified Red or non-microemulsified Red. The second trial involved feeding microemulsified Yellow or non-microemulsified Yellow using a similar dosage range. The layers were divided into 4 replicates of 8 layers each (32 layers per treatment). The 8 cages of layers were fed from a single feed trough. Feed and water were provided ad libitum throughout the trial. Each week, the eggs were collected. The whole liquid egg colour was determined by means of a commercially available yolk colour fan. Where required, HPLC-(high-performance liquid chromatography) based analysis of trans-capsanthin or trans-lutein equivalents using the Association of Analytical Communities method was carried out. Data were statistically analysed by one-way ANOVA method using Statgraphics. 3. Results showed that the colour and carotenoid content of the egg yolk increased with increasing amount of carotenoids in the diet. The colour of egg yolks from layers fed similar concentrations of microemulsified versus the regular preparation was significantly different. At the commercial recommended dose of one g/kg regular Yellow or Red product, the microemulsified pigmenter is able to provide the equivalent yolk colour at a 20-30% lower dose. 4. In conclusion, the trial results supported the hypothesis that a desired yolk colour score is achievable at a significantly lower inclusion rate when carotenoid molecules are emulsified using the microemulsion nanotechnology.


Assuntos
Carotenoides/metabolismo , Galinhas/metabolismo , Gema de Ovo , Pigmentos Biológicos , Animais , Carotenoides/química , Emulsões , Tamanho da Partícula
9.
Inorg Chem ; 52(2): 832-9, 2013 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-23298404

RESUMO

The pressure-induced valence change of Yb in YbMn(2)Ge(2) has been studied by high pressure inelastic X-ray emission and absorption spectroscopy in the partial fluorescence yield mode up to 30 GPa. The crystal structure of YbMn(2)Ge(2) has been investigated by high pressure powder X-ray diffraction experiments up to 40 GPa. The experimental investigations have been complemented by first principles density functional theoretical calculations using the generalized gradient approximation with an evolutionary algorithm for structural determination. The Yb valence and magnetic structures have been calculated using the self-interaction corrected local spin density approximation. The X-ray emission results indicate a sharp increase of Yb valence from v = 2.42(2) to v = 2.75(3) around 1.35 GPa, and Yb reaches a near trivalent state (v = 2.95(3)) around 30 GPa. Further, a new monoclinic P1 type high pressure phase is found above 35 GPa; this structure is characterized by the Mn layer of the ambient (I4/mmm) structure transforming into a double layer. The theoretical calculations yield an effective valence of v = 2.48 at ambient pressure in agreement with experiment, although the pure trivalent state is attained theoretically at significantly higher pressures (above 40 GPa).

10.
World J Surg ; 37(6): 1356-61, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23463394

RESUMO

BACKGROUND: The purpose of the present study was to determine whether intrahepatic injection of (131)I-lipiodol (Lipiodol) is effective against recurrence of surgically resected hepatocellular carcinoma (HCC). METHODS: From June 2001 through March 2007, this nationwide multi-center prospective randomized controlled trial enrolled 103 patients 4-6 weeks after curative resection of HCC with complete recovery (52: Lipiodol, 51: Control). Follow-up was every 3 months for 1 year, then every 6 months. Primary and secondary endpoints were recurrence-free survival (RFS) and overall survival (OS), respectively, both of which were evaluated by the Kaplan-Meier technique and summarized by the hazard ratio (HR). The design was based on information obtained from a similar trial that had been conducted in Hong Kong. RESULTS: The Lipiodol group showed a small, and nonsignificant, improvement over control in RFS (HR = 0.75; 95 % confidence interval [95 % CI] 0.46-1.23; p = 0.25) and OS (HR = 0.88; 95 % CI 0.51-1.51; p = 0.64). Only two serious adverse events were reported, both with hypothyroidism caused by (131)I-lipiodol and hepatic artery dissection during angiography. CONCLUSIONS: The randomized trial provides insufficient evidence to recommend the routine use of (131)I-lipiodol in these patients.


Assuntos
Antineoplásicos/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/cirurgia , Óleo Etiodado/uso terapêutico , Radioisótopos do Iodo/uso terapêutico , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/cirurgia , Idoso , Quimioterapia Adjuvante , Feminino , Humanos , Injeções Intra-Arteriais , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Taxa de Sobrevida , Resultado do Tratamento
11.
J Synchrotron Radiat ; 19(Pt 2): 245-51, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22338686

RESUMO

Core-shell X-ray emission spectroscopy (XES) is a valuable complement to X-ray absorption spectroscopy (XAS) techniques. However, XES in the hard X-ray regime is much less frequently employed than XAS, often as a consequence of the relative scarcity of XES instrumentation having energy resolutions comparable with the relevant core-hole lifetimes. To address this, a family of inexpensive and easily operated short-working-distance X-ray emission spectrometers has been developed. The use of computer-aided design and rapid prototype machining of plastics allows customization for various emission lines having energies from ∼3 keV to ∼10 keV. The specific instrument described here, based on a coarsely diced approximant of the Johansson optic, is intended to study volume collapse in Pr metal and compounds by observing the pressure dependence of the Pr Lα emission spectrum. The collection solid angle is ∼50 msr, roughly equivalent to that of six traditional spherically bent crystal analyzers. The miniature X-ray emission spectrometer (miniXES) methodology will help encourage the adoption and broad application of high-resolution XES capabilities at hard X-ray synchrotron facilities.

12.
Br J Surg ; 99(12): 1622-9, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23023956

RESUMO

BACKGROUND: Long-term overall survival after liver resection in patients with hepatocellular carcinoma (HCC) within the Milan criteria has been reported to improve in recent years. This study systematically reviewed the outcomes of surgical resection for HCC in patients with good liver function and meeting the Milan criteria for early HCC, published in the past 10 years. METHODS: A literature search was conducted in PubMed for papers on outcomes of surgical resection for HCC published between January 2000 and December 2010. Cochrane systematic review methodology was used for this review. The primary outcome was overall survival. Secondary outcomes included operative mortality and disease-free survival. Studies that focused on geriatric populations, paediatric populations, a subset of the Milan criteria (such solitary tumours) or included patients with incidental tumours were excluded, as were case reports, conference abstracts, and studies with a large proportion of Child-Pugh grade C liver cirrhosis or unknown Child-Pugh status. RESULTS: Of 152 studies reviewed, two randomized clinical trials and 27 retrospective case series were eligible for inclusion. The 5-year overall survival rate after resection of HCC ranged from 27 to 81 (median 67) per cent, and the median disease-free survival rate from 21 to 57 (median 37) per cent. There was a trend towards improved overall survival in recent years. The operative mortality rate ranged from 0 to 5 (median 0·7) per cent. CONCLUSION: Surgical resection offers good overall survival for patients with HCC within the Milan criteria and with good liver function, although recurrence rates remain high. Outcomes have tended to improve in more recent years.


Assuntos
Carcinoma Hepatocelular/cirurgia , Hepatectomia/métodos , Neoplasias Hepáticas/cirurgia , Carcinoma Hepatocelular/mortalidade , Intervalo Livre de Doença , Hepatectomia/mortalidade , Humanos , Neoplasias Hepáticas/mortalidade , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Retrospectivos , Resultado do Tratamento
13.
Phys Rev Lett ; 109(19): 195705, 2012 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-23215404

RESUMO

High-pressure x-ray emission measurements are used to provide crucial evidence in the longstanding debate over the nature of the isostructural (α, γ) volume collapse in elemental cerium. Extended local atomic model calculations show that the satellite of the Lγ emission line offers direct access to the total angular momentum observable (J(2)). This satellite experiences a 30% steplike decrease across the volume collapse, validating the Kondo model in conjunction with previous measurements. Direct comparisons are made with previous predictions by dynamical mean field theory. A general experimental methodology is demonstrated for analogous work on a wide range of strongly correlated f-electron systems.


Assuntos
Cério/química , Modelos Químicos , Transição de Fase , Teoria Quântica , Espectrometria por Raios X/métodos
14.
Sci Rep ; 12(1): 631, 2022 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-35022446

RESUMO

Polyethylene (C2H4)n was compressed to pressures between 10 and 30 GPa in a diamond anvil cell (DAC) and laser heated above 2500 K for approximately one second. This resulted in the chemical decomposition of the polymer into carbon and hydrocarbon reaction products. After quenching to ambient temperature, the decomposition products were measured in the DAC at pressures ranging from ambient to 29 GPa using a combination of x-ray diffraction (XRD) and small angle x-ray scattering (SAXS). XRD identified cubic diamond and methane as the predominant product species with their pressure-volume relationships exhibiting strong correlations to the diamond and methane equations of state. Length scales associated with the diamond products, obtained from SAXS measurements, indicate the formation of nanodiamonds with a radius of gyration between 12 and 35 nm consistent with 32-90 nm diameter spherical particles. These results are in good agreement with the predicted product composition under thermodynamic and chemical equilibrium.

15.
Br J Cancer ; 105(7): 945-52, 2011 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-21863030

RESUMO

BACKGROUND: Hepatocellular carcinoma (HCC) is the third leading cause of cancer deaths worldwide. We tested megestrol acetate (MA) against placebo in the treatment of advanced HCC. METHODS: From 2002 through 2007, this randomised double-blind trial enrolled 204 patients with treatment-naive advanced HCC (Eastern Cooperative Oncology Group (ECOG) performance rating of 0-3) from specialist care centres in six Asia-Pacific nations. Patients received placebo or MA (320 mg day(-1)). End points were overall survival (OS) and quality of life. RESULTS: An adverse but not statistically significant difference in OS was found for MA vs placebo: median values 1.88 and 2.14 months, respectively (hazard ratio (HR)=1.25, 95% CI=0.92-1.71, P=0.16). However, OS was similar among patients of good functional status (Child-Pugh A and ECOG 0, 1 or 2) (44.3%) in both treatment groups, with the adverse effect of MA confined to those of poor status. Megestrol acetate patients had a worse global health status (not statistically significant) but reduced levels of appetite loss and nausea/vomiting. CONCLUSION: Megestrol acetate has no role in prolonging OS in advanced treatment-naive HCC. Overall survival with placebo differed markedly from that in similar trials conducted elsewhere, suggesting therapeutic outcomes may be strongly dependent on ECOG status and Child-Pugh score.


Assuntos
Antineoplásicos Hormonais/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Acetato de Megestrol/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Hepatocelular/patologia , Método Duplo-Cego , Feminino , Seguimentos , Humanos , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Qualidade de Vida , Taxa de Sobrevida , Resultado do Tratamento , Adulto Jovem
16.
Mol Psychiatry ; 15(8): 844-9, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19255581

RESUMO

The gene known as Disrupted-in-Schizophrenia-1, DISC1, was originally discovered in a large family, in which it also co-segregated with bipolar affective disorder (BD) and with major depressive disorder (MDD). The TSNAX (Translin-associated factor X) gene, located immediately upstream of DISC1, has also been suggested as a candidate gene in relation to psychiatric illness, as one transcript resulting from intergenic splicing encodes a novel TSNAX-DISC1 fusion protein. We explored the TSNAX-DISC1 gene region for an association with BD and MDD in a sample of 1984 patients (1469 MDD, 515 BD) and 1376 ethnically matched controls. Eight single nucleotide polymorphisms (SNPs) within the TSNAX-DISC1 region (rs766288, rs3738401, rs2492367, rs6675281, rs12133766, rs1000731, rs7546310 and rs821597) were investigated using the SNPlex Genotyping System. We found a significant allelic and genotypic association of the TSNAX-DISC1 gene region with BD, whereas a haplotypic association was found for both BD and MDD. Therefore, our results suggest an association between the TSNAX-DISC1 region and both forms of affective disorders, and support the hypothesis that a portion of the genotypic overlap between schizophrenia and affective disorders is attributable to this gene.


Assuntos
Transtorno Bipolar/genética , Proteínas de Ligação a DNA/genética , Depressão/genética , Predisposição Genética para Doença , Proteínas do Tecido Nervoso/genética , Polimorfismo de Nucleotídeo Único/genética , Adulto , Estudos de Casos e Controles , Feminino , Frequência do Gene , Estudo de Associação Genômica Ampla/métodos , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade
17.
Tree Physiol ; 41(9): 1563-1582, 2021 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-33554258

RESUMO

In an attempt to comprehensively study the dynamics of non-structural carbon compounds (NCCs), we measured the seasonal changes of soluble sugars, starch, lipids and sugar alcohols in the leaves, branches, stem and roots of the fast-growing Pinus contorta (Loudon) (pine) and slow-growing Picea glauca (Moench) Voss (spruce) trees growing in a boreal climate. In addition to measuring the seasonal concentrations of these compounds, the relative contribution of these compounds to the total NCC pool within the organs of trees (~8 m tall) was estimated and compared across different phenological and growth stages. Both species showed large seasonal shifts from starch to sugars from spring to fall in nearly all organs and tissues; most likely an adaptation to the cold winters. For both species, the total fluctuation of sugar + starch across the year (i.e., the difference between the minimum and maximum observed across collection times) was estimated to be between 1.6 and 1.8 kg for all NCCs. The fluctuation, however, was 1.40 times greater than the minimum reserves in pine, while only 0.72 times the minimum reserves in spruce. By tissue type, NCC fluctuations were greatest in the roots of both species. Roots showed a large build-up of reserves in late spring, but these reserves were depleted over summer and fall. Storage reserves in needles and branches declined over the summer, and this decline may be linked to the sink strength of the stem during diameter growth. Some notable highlights of this holistic study: a late winter build-up of sugars in the stem xylem of both species, but especially spruce; and an increase in sugar alcohols in the bark of spruce in very late winter, which could indicate mobilization to support early growth in spring and high lipid reserves in the bark of pine, which appeared not to be impacted by seasonal changes between summer and winter. Collectively, these observations point toward a more conservative NCC reserve strategy in spruce compared with pine, which is consistent with its stress tolerance and greater longevity.


Assuntos
Picea , Pinus , Traqueófitas , Carbono , Estações do Ano , Árvores
19.
Am J Med Genet B Neuropsychiatr Genet ; 153B(1): 141-7, 2010 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-19367584

RESUMO

The Neuregulin 1 (NRG1) gene was initially implicated in schizophrenia (SZ) and has recently been associated with bipolar disorder (BPD) in two studies. An association with major depressive disorder (MDD) has not yet been investigated but is warranted in view of the genetic overlap between MDD and BPD. We have performed a large-scale case-control study investigating the association between NRG1 polymorphisms and MDD, genotyping a selection of 14 single nucleotide polymorphisms (SNPs) spanning the NRG1 gene in a sample of 1,398 patients of White European ancestry with a diagnosis of MDD and 1,304 ethnically matched controls from three clinical sites in the UK. We found no single marker or haplotype associations that withstood correction for multiple testing. Our findings do not provide evidence that NRG1 plays a role in MDD or that this gene explains part of the genetic overlap with BPD.


Assuntos
Transtorno Depressivo Maior/genética , Neuregulina-1/genética , Estudos de Casos e Controles , Europa (Continente) , Marcadores Genéticos , Humanos , Polimorfismo de Nucleotídeo Único , Recidiva , Reino Unido
20.
Diabet Med ; 26(7): 693-9, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19573118

RESUMO

AIMS: The Joint Asia Diabetes Evaluation (JADE) Program is the first web-based program incorporating a comprehensive risk engine, care protocols, clinical decision and self-management support to improve ambulatory diabetes care. The aim was to validate the risk stratification system of the JADE Program using a large prospective cohort. METHODS: The JADE interactive risk engine stratifies patients into different risk levels using results from an annual comprehensive assessment of complications and risk factors. We used a prospective registry consisting of 7534 Type 2 diabetic patients [45.6% men, median (range) age 57 years (13-92)] to perform internal validation of the risk engine. RESULTS: The JADE Risk Engine categorized patients into four risk levels (from low to high): level 1, n = 4520 (6%); level 2, n = 1468 (19.5%); level 3, n = 4476 (59.4%); and level 4, n = 1138 (15.1%). After a median follow-up period of 5.5 years (mean +/- sd 5.4 +/- 2.81 years), 763 (10.1%) died, 1129 (14.9%) developed cardiovascular disease (CVD), 282 (3.7%) developed end-stage renal disease and 1400 (18.6%) had at least one of these events. Compared with risk level 1, levels 2, 3 and 4 were associated with 2.8-, 4.7- and 8.6-fold increased risk of clinical end-points. Risk levels 3 and 4 were, respectively, associated with 2.2- and 3.9-fold increased risk for all-cause death and 4.8- and 12.1-fold increased CVD risks. CONCLUSION: Based on results from a comprehensive assessment, the JADE Risk Engine successfully categorizes patients into different risk levels to guide clinical management.


Assuntos
Sistemas de Apoio a Decisões Clínicas , Atenção à Saúde/normas , Diabetes Mellitus Tipo 2/epidemiologia , Internet , Sistema de Registros/estatística & dados numéricos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Ásia , Estudos de Coortes , Diabetes Mellitus Tipo 2/complicações , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Avaliação de Programas e Projetos de Saúde , Medição de Risco/métodos , Fatores de Risco , Software , Adulto Jovem
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