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1.
Dalton Trans ; 46(6): 1770-1778, 2017 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-28074207

RESUMO

This study combines electron microscopy equipped with energy dispersive spectroscopy to probe major element composition and autoradiography to map plutonium in order to examine the spatial relationships between plutonium and fallout composition in aerodynamic glassy fallout from a nuclear weapon test. A sample set of 48 individual fallout specimens were interrogated to reveal that the significant chemical heterogeneity of this sample set could be described compositionally with a relatively small number of compositional endmembers. Furthermore, high concentrations of plutonium were never associated with several endmember compositions and concentrated with the so-called mafic glass endmember. This result suggests that it is the physical characteristics of the compositional endmembers and not the chemical characteristics of the individual component elements that govern the un-burnt plutonium distribution with respect to major element composition in fallout.

2.
Metabolomics ; 12: 38, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26848289

RESUMO

The quality of rice in terms not only of its nutritional value but also in terms of its aroma and flavour is becoming increasingly important in modern rice breeding where global targets are focused on both yield stability and grain quality. In the present paper we have exploited advanced, multi-platform metabolomics approaches to determine the biochemical differences in 31 rice varieties from a diverse range of genetic backgrounds and origin. All were grown under the specific local conditions for which they have been bred and all aspects of varietal identification and sample purity have been guaranteed by local experts from each country. Metabolomics analyses using 6 platforms have revealed the extent of biochemical differences (and similarities) between the chosen rice genotypes. Comparison of fragrant rice varieties showed a difference in the metabolic profiles of jasmine and basmati varieties. However with no consistent separation of the germplasm class. Storage of grains had a significant effect on the metabolome of both basmati and jasmine rice varieties but changes were different for the two rice types. This shows how metabolic changes may help prove a causal relationship with developing good quality in basmati rice or incurring quality loss in jasmine rice in aged grains. Such metabolomics approaches are leading to hypotheses on the potential links between grain quality attributes, biochemical composition and genotype in the context of breeding for improvement. With this knowledge we shall establish a stronger, evidence-based foundation upon which to build targeted strategies to support breeders in their quest for improved rice varieties.

3.
Theor Appl Genet ; 123(4): 519-25, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21562821

RESUMO

Gel consistency (GC) is a standard assay used in rice improvement programmes to determine whether rice cultivars/breeding lines of high amylose content are soft or firm textured when cooked. In this study, we show that sequence variation in exon 10 of the Waxy (Wx) gene associates with GC using RILs derived from parents with high amylose content that differ in GC. The association was validated using a diverse set of traditional varieties, selected on the basis of amylose content, from the generation challenge programme. Structural investigations to explain how the mutation leads to differences in GC showed a strong association between GC and the proportion of amylose that leaches. It was shown that cooked rices of hard GC do not change in hardness over 24 h, whereas rices of soft GC retrograde significantly over 24 h. This leads to the conclusion that the mutation on exon 10 of the Wx gene affects the proportion of amylose bound to amylopectin and the proportion able to leach, and these structural differences alter the composition of the gel, which affects the amount of time the gel takes to reach a final hardness. The SNP described here completes the set of markers required to genotype for the current traits of cooking quality, but selecting the allele for soft texture has the negative result of also selecting for retrogradation potential.


Assuntos
Genes de Plantas , Oryza/genética , Proteínas de Plantas/genética , Polimorfismo de Nucleotídeo Único , Sintase do Amido/genética , Alelos , Amilopectina/química , Amilose/química , Cruzamentos Genéticos , Éxons , Regulação da Expressão Gênica de Plantas , Genótipo , Oryza/metabolismo , Proteínas de Plantas/metabolismo , Sintase do Amido/metabolismo
4.
J Agric Food Chem ; 51(8): 2295-9, 2003 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-12670173

RESUMO

Rice breeders frequently use rapid visco analysis (RVA) as in index of rice quality. Potentially, viscosity curves could also be used to predict the sensory properties of a sample of rice or the processing properties of rice when used as an ingredient. The aim of this study is to determine the contribution of the main components of rice flour-starch and protein polymers and lipids-to the viscosity curve, accounting for biological and rheological contributions, and interactions with water. By deconstructing the rice flour, resistance to shear is generally the primary factor that affects rheological processes in the RVA, often masking the physical processes of cooking. Thus, higher concentrations of water reveal more about the true biological and physical processes of the transition from a powder to paste. Proteins contribute to peak height, offset thixotropy, and contribute to the final viscosity. Starch-lipid complexes can mask differences in the molecular structures of amylose and amylopectin, and removing lipids alters the structure of the paste significantly, which consequently alters viscosity curves.


Assuntos
Farinha/análise , Oryza/química , Amilose/química , Temperatura Alta , Lipídeos/química , Proteínas de Plantas/química , Polímeros/química , Reologia , Amido/química , Viscosidade , Água/química
5.
J Exp Bot ; 52(360): 1519-26, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11457912

RESUMO

Experiments were conducted to investigate the effect of S nutrition and availability on the forms of S and N in the endosperm cavity and endosperm of wheat, and on the capacity of the endosperm to utilize those compounds for the synthesis of proteins. Plants were grown in solution culture with 2 mM N and either 200 microM S (high-S) or 50 microM S (low-S) and all nutrients were withdrawn at various times from booting until 8 d post-anthesis. Sulphate was the major form of soluble S in the endosperm cavity and endosperm of high-S plants during the time of rapid grain development. By contrast, glutathione (GSH) was the major form of soluble S in the endosperm cavity and in the endosperm in low-S plants. Crude extracts of endosperm tissue from both high-S and low-S plants supported (i) the hydrolysis of GSH to gamma-glutamyl cysteine and glycine, and of gamma-glutamyl cysteine to glutamate and cysteine, and (ii) sulphate-dependent PPi-ATP exchange and the sulphydration of O-acetylserine catalysed by ATP sulphurylase and cysteine synthase, respectively. High-S nutrition enhanced the in vitro rates of ATP sulphurylase and cysteine synthase.


Assuntos
Sementes/fisiologia , Enxofre/metabolismo , Triticum/crescimento & desenvolvimento , Trifosfato de Adenosina , Cisteína/metabolismo , Cisteína Sintase/metabolismo , Glutamato-Cisteína Ligase , Ácido Glutâmico/metabolismo , Glutationa/biossíntese , Glicina/metabolismo , Nitrogênio/química , Nitrogênio/metabolismo , Nitrogênio/farmacologia , Sulfatos/metabolismo , Enxofre/química , Enxofre/farmacologia , Triticum/metabolismo
6.
J Clin Oncol ; 19(6): 1809-17, 2001 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-11251013

RESUMO

PURPOSE: To report the reliability and validity of the Functional Assessment of Cancer Therapy-Ovarian (FACT-O) in a consecutive series of outpatients with epithelial ovarian cancer. PATIENTS AND METHODS: Two hundred thirty-two ovarian cancer patients attending an outpatient gynecologic oncology clinic completed questionnaires at baseline. The patients' FACT-O scores were compared with their performance status, disease stage, treatment status, and other factors hypothesized to be related to quality of life. Patients received a second questionnaire either one week after baseline to assess the instrument's test-retest reliability and/or two months after baseline to evaluate its sensitivity to change in performance status. RESULTS: Internal consistency and test-retest reliability of the FACT-O were adequate. Overall, the scales correlated with other measures as expected; all correlations were in the hypothesized direction. Patients with advanced disease, poor performance status, and who were receiving active treatment had lower scores on physical, functional, and ovarian cancer-specific scales. The total FACT-O and emotional well-being scores were lower for patients with poor performance status and patients in active treatment. The FACT-O total and all subscale scores except emotional well-being were sensitive to decreases in performance status. CONCLUSION: Overall, the FACT-O provides a reliable and valid assessment of the quality of life of women with ovarian cancer, and is appropriate as a brief quality of life assessment in clinical trials and descriptive studies.


Assuntos
Neoplasias Ovarianas/psicologia , Qualidade de Vida , Atividades Cotidianas , Adulto , Idoso , Ensaios Clínicos como Assunto , Emoções , Saúde da Família , Feminino , Nível de Saúde , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Ovarianas/complicações , Neoplasias Ovarianas/terapia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Apoio Social , Inquéritos e Questionários/normas , Resultado do Tratamento
9.
Clin Diagn Lab Immunol ; 7(6): 885-8, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11063492

RESUMO

Iron deficiency anemia is a common public health problem in the Alaska Native population. Yet, a clear etiology has eluded researchers for decades. Previous studies suggested a link between Helicobacter pylori infection, gastrointestinal blood loss due to hemorrhagic gastritis, and generalized iron deficiency anemia in adult Alaska Natives. Therefore, we examined the association between the prevalence of H. pylori-specific immunoglobulin G (IgG) and serum ferritin levels, a marker of iron deficiency. A random sample of 2,080 serum samples from Alaska Native residents drawn between 1980 and 1986 from residents in 13 regions was selected, and the samples were stratified by age, sex, and region. Overall, 75% were positive for H. pylori-specific IgG. The rate of H. pylori seropositivity increased with age; by age 14 years, 78% of the residents were positive. There were no gender differences in H. pylori seropositivity. However, marked regional differences were observed. Serum ferritin levels of <12 ng/ml were found most commonly among persons <20 years of age and among women of childbearing age. A significant association between low serum ferritin levels and prevalence of H. pylori-specific IgG was found, particularly for people aged less than 20 years. H. pylori may be a factor contributing to the iron deficiency anemia in the Alaska Native population.


Assuntos
Ferritinas/sangue , Infecções por Helicobacter/sangue , Infecções por Helicobacter/epidemiologia , Helicobacter pylori , Adolescente , Adulto , Alaska/epidemiologia , Anemia Ferropriva/sangue , Anemia Ferropriva/epidemiologia , Anemia Ferropriva/etiologia , Anticorpos Antibacterianos/sangue , Criança , Pré-Escolar , Feminino , Infecções por Helicobacter/complicações , Helicobacter pylori/imunologia , Humanos , Imunoglobulina G/sangue , Indígenas Norte-Americanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade
12.
Gynecol Oncol ; 78(3 Pt 1): 302-8, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10985884

RESUMO

OBJECTIVE: The aims of this study were to evaluate psychological distress and quality of life (QOL) in patients with epithelial ovarian cancer (EOC) and to examine the relationship between these problems and health and demographic variables. METHODS: Of 344 consecutive patients identified, 246 completed questionnaires. Four dimensions of QOL were assessed including physical, functional, emotional, and social/family well-being, as well as concerns specific to ovarian cancer patients. Depression was measured with the Center for Epidemiologic Studies-Depression (CES-D) scale and anxiety was measured by the State Anxiety Subscale of the Spielberger State-Trait Anxiety Inventory. Performance status was evaluated by the Zubrod score. RESULTS: Sixty-five patients (26%) had early stage disease; 181 (74%) had advanced disease. One hundred twenty-one patients (49%) were under active treatment, while 124 (51%) were seen for posttherapy surveillance. Forty-eight (21%) met CES-D cutoff criteria for a clinical evaluation for depression, and 29% scored above the 75th percentile for anxiety. Performance status was related to depression, anxiety, and QOL problems, except in the domain of social well-being. CONCLUSIONS: Clinically significant depression and anxiety may be more prevalent in patients with EOC than previously reported. Future studies of screening for and treating psychological distress are being designed to improve QOL in these women.


Assuntos
Ansiedade/etiologia , Depressão/etiologia , Neoplasias Ovarianas/psicologia , Adulto , Idoso , Ansiedade/epidemiologia , Depressão/epidemiologia , Células Epiteliais/patologia , Feminino , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/terapia , Prevalência , Qualidade de Vida , Análise de Regressão , Índice de Gravidade de Doença , Inquéritos e Questionários
16.
Nurse Pract ; 24(10 Suppl): 10-4, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10546264

RESUMO

Nearly two-thirds of all children will have at least one episode of acute otitis media (AOM) by age 2 years. Acute otitis media is the most common indication for pediatric outpatient and antibiotic therapy. Minimizing AOM risk factors, prescribing the most appropriate and effective AOM therapy while limiting inappropriate antimicrobial use is an important part of the pediatric primary care.


Assuntos
Profissionais de Enfermagem , Otite Média/tratamento farmacológico , Otite Média/enfermagem , Doença Aguda , Adolescente , Adulto , Criança , Pré-Escolar , Resistência a Medicamentos , Humanos , Lactente , Recém-Nascido , Otite Média/complicações , Otite Média/etiologia , Planejamento de Assistência ao Paciente , Fatores de Risco
19.
J Infect Dis ; 179(1): 101-6, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9841828

RESUMO

Before vaccination, Alaska Natives experienced very high rates of invasive Haemophilus influenzae type b (Hib) disease and carriage. Vaccination with Hib conjugate vaccine PRP-OMP (polyribosylribitol phosphate Neisseria meningitidis outer membrane protein) began in 1991 and resulted in a sharp decline in cases. In 1996, after switching to a different Hib conjugate vaccine, DTP-HbOC (which combines diphtheria-tetanus-whole cell pertussis vaccines with HbOC [Hib oligosaccharide CRM197]), cases of invasive Hib disease increased, suggesting ongoing Hib transmission despite widespread vaccination. To determine the prevalence of and risk factors for carriage, a cross-sectional study of oropharyngeal Hib carriage was conducted among Alaska Native children aged 1-5 years in remote southwestern Alaska. Of 496 children with swabs taken, 46 (9.3%) were colonized with Hib. Carriage rates varied by village from 2.2% to 13.2% and by age from 6.1% in 1-year-olds to 14.7% in 5-year-olds. Crowding was associated with Hib carriage. Widespread vaccination with PRP-OMP Hib conjugate vaccine did not eliminate carriage in this population of Alaska Natives, and ongoing carriage contributed to disease resurgence.


Assuntos
Infecções por Haemophilus/epidemiologia , Vacinas Anti-Haemophilus/efeitos adversos , Haemophilus influenzae tipo b , Fatores Etários , Alaska/epidemiologia , Portador Sadio/epidemiologia , Pré-Escolar , Estudos Transversais , Feminino , Infecções por Haemophilus/prevenção & controle , Infecções por Haemophilus/transmissão , Humanos , Indígenas Norte-Americanos , Lactente , Masculino , Orofaringe/microbiologia , Fatores de Risco , População Rural
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