Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 20
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
Int J Cosmet Sci ; 41(2): 132-146, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30719733

RESUMO

OBJECTIVE: A new hair-care process has been specifically developed for the straightening of curved Japanese woman's hair . The process included sodium 2-naphthalene sulfonate (SNS) in the reduction and oxidation steps of a conventional perming process. Our objective was to develop an understanding of how this process caused hair straightening by measuring the changes to morphology and ultrastructure between untreated, conventionally permed and SNS permed hair. Untreated and SNS permed Merino wool fibres were used to confirm structural changes. METHODS: Japanese hair samples were measured for single-fibre curvature before and after perming treatments. A silver staining method was developed to stain hair fibres without changing fibre curvature so that transmission electron microscopy could be used to measure changes in the lateral dimensions of all structural components from the cellular to protein filament level. Electron tomography determined intermediate filament slopes and slope changes after SNS perming relative to the central longitudinal axis of the fibre. RESULTS: SNS perming was found to cause greater lateral swelling than conventional perming of: the paracortical cells of wool; the cuticle, the cuticular cell membrane complex and the macrofibrillar centre-to-centre distance of hair; and of the intermediate filaments in wool and hair. In curved hair, SNS perming caused the intermediate filaments of the helical macrofibrils to simultaneously swell and to tilt further, resulting in the slight longitudinal contraction of the macrofibrils. The overall swelling and tilting was greatest in the helical macrofibrils of Type B cortical cells predominately located in the convex fibre half. The presence of a higher percentage of helical macrofibrils in the convex fibre half than in the concave fibre half caused a contraction differential between the two halves leading to straighten of the curved fibre. A mechanical model was proposed to explain how SNS perming straightened curly hair. CONCLUSION: The effects of conventional and SNS perming on the morphological and ultrastructural components of curved Japanese hair and high-curl Merino wool fibres have given clear insights into understanding the mechanism of fibre curvature change.


OBJECTIF: Un nouveau procédé de soin des cheveux a été spécialement conçu pour lisser les cheveux ondulés des Japonaises[1]. Le procédé utilise le sulfonate de naphthalène-2 sodium (SNS) dans les étapes de réduction et d'oxydation du procédé conventionnel de permanente. Notre objectif était de comprendre la façon dont ce procédé induisait le lissage des cheveux en mesurant les différences de changement morphologique et ultrastructural entre les cheveux non traités et ceux soumis à une permanente conventionnelle et une permanente à base de SNS. Des fibres de laine de mérinos non traitées et soumises à une permanente à base de SNS ont été utilisées pour confirmer les changements structurels. MÉTHODES: Des échantillons de cheveux japonais ont été utilisés pour mesurer la courbure d'une fibre isolée avant et après le traitement de permanente. Une méthode de coloration argent a été mise au point pour colorer les fibres de cheveux sans changer la courbure des fibres afin de pouvoir utiliser la microscopie électronique en transmission pour mesurer les modifications des dimensions en largeur de tous les composants structurels du filament, de la cellule aux protéines. Une tomographie électronique a déterminé les pentes intermédiaires et les changements de pente des filaments après permanente à base de SNS par rapport à l'axe longitudinal central de la fibre. RÉSULTATS: On a constaté que la permanente à base de SNS induisait un gonflement en largeur plus important que la permanente classique des cellules paracorticales de la laine; de la cuticule, du complexe de la membrane cellulaire cuticulaire et de la distance centre à centre des macrofibrilles du cheveu; et des filaments intermédiaires dans la laine et les cheveux. Dans les cheveux ondulés, la permanente à base de SNS a provoqué à la fois un gonflement et une inclinaison des filaments intermédiaires des macrofibrilles hélicoïdales, entraînant une légère contraction longitudinale des macrofibrilles. Au total, le gonflement et l'inclinaison étaient plus importants dans les macrofibrilles hélicoïdales des cellules corticales de type B situées principalement dans la moitié convexe de la fibre. La présence d'un pourcentage plus élevé de macrofibrilles hélicoïdales dans la moitié convexe par rapport à la moitié concave de la fibre a entraîné une contraction différentielle entre les deux moitiés qui a entraîné le redressement de la fibre courbée. Un modèle mécanique a été proposé pour expliquer comment la permanente à base de SNS lissait les cheveux bouclés. CONCLUSION: Les effets de la permanente conventionnelle et à base de SNS sur les composants morphologiques et ultrastructuraux des cheveux japonais ondulés et des fibres de laine très frisés de mérinos ont permis de mieux comprendre le mécanisme du changement de courbure des fibres.


Assuntos
Preparações para Cabelo , Cabelo/química , Microscopia Eletrônica de Transmissão/métodos , Naftalenossulfonatos/química , Tomografia/métodos , Animais , Povo Asiático , Feminino , Cabelo/ultraestrutura , Humanos , Japão , Ovinos
2.
Int J Cosmet Sci ; 40(6): 536-548, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30229956

RESUMO

OBJECTIVE: To understand the structural and chemical effects of cosmetic peroxide bleaching on human hair. METHODS: Human hair was progressively bleached using alkaline peroxide-persulphate treatment. Proteins lost through leaching were examined using amino acid analysis and mass spectrometric sequencing. Fibre damage was assessed using transmission electron microscopy, amino acid analysis and redox proteomics. RESULTS: Protein loss through leaching increased with bleaching severity. Leached proteins were not limited to the cuticle, but also included cortical intermediate filaments and matrix keratin-associated proteins. The leached proteins were progressively oxidized as bleaching severity increased. Bleached fibres demonstrated substantial damage to the cuticle layers and to the cortex. Extensive melanin granule degradation was present after the mildest bleach treatment. Protein oxidation in bleached fibres was principally in cortical intermediate filaments - the most abundant hair proteins - and targeted the sulphur-containing amino acids, particularly the conversion of cystine disulphide bonds to cysteic acid. CONCLUSION: Peroxide chemical treatments quickly access the cortex, causing untargeted oxidative damage across the fibre in addition to the desired loss of melanin. Peroxide ingress is likely facilitated by the considerable structural degradation caused to the cuticle layers of hair fibres. The consequences of the peroxide action within the cuticle and cortex are oxidation of the proteins, and subsequent protein loss from the fibre that correlates to bleaching severity.


Assuntos
Cabelo/química , Peróxido de Hidrogênio/química , Microscopia Eletrônica de Transmissão/métodos , Aminoácidos/análise , Humanos , Oxirredução
3.
J Econ Entomol ; 107(2): 875-9, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24772573

RESUMO

The hop looper, Hypena humuli Harris, is a reemergent pest of hop that often requires treatment to mitigate crop damage. In 4 yr of field trials, plots treated with fungicides were observed to sustain less hop looper defoliation compared with nontreated plots. Further investigation revealed that abundance of hop looper and associated defoliation were reduced when the fungicide pyraclostrobin was applied in late July to early August. Two other fungicides possessing active ingredients in the same chemical family (quinone outside inhibitor) did not reduce abundance of hop looper or its defoliation. Pyraclostrobin is efficacious against powdery mildew diseases, and the application timing evaluated in these studies corresponds with a period of juvenile susceptibility of hop cones to the disease. Use of fungicides containing pyraclostrobin at this time may have the ancillary benefit of reducing hop looper damage, potentially obviating the need for broad-spectrum insecticides later in the season. Follow-up studies are warranted to determine whether pyraclostrobin may inhibit other lepidopteran species.


Assuntos
Carbamatos , Humulus/crescimento & desenvolvimento , Inseticidas , Mariposas , Pirazóis , Animais , Feminino , Fungicidas Industriais , Larva/crescimento & desenvolvimento , Mariposas/crescimento & desenvolvimento , Oregon , Estações do Ano , Estrobilurinas
4.
J Econ Entomol ; 107(2): 570-81, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24772536

RESUMO

The temporal development of biological control of arthropod pests in perennial cropping systems is largely unreported. In this study, the development of biological control of twospotted spider mite, Tetranychus urticae Koch, and hop aphid, Phorodon humuli (Schrank), in a new planting of hop in Oregon is described over a period of 9 yr (2005-2013). Both the abundance and diversity of natural enemies increased over time. Known predators of hop aphid (Coccinellidae and Anthocoridae) were present in all years; however, stable biological control of hop aphid was not achieved in most years and aphicides were required to suppress populations at commercially acceptable levels in 5 of 9 yr. Populations of aphidophagous coccinellids developed synchronously with hop aphid populations, and temporal correlations indicated these are the primary predatory insect associated with hop aphid regulation. However, sampling methods did not assess levels of aphid parasitoids and hyperparasitoids and their contribution to biological control was unquantified. Spider mite biological control was associated primarily with predatory mites (Phytoseiidae) and Stethorus spp. (Coccinellidae). The magnitude of temporal correlations of abundance of these predators with spider mites was found to be greatest on the same sampling dates and at lags of 7-14 d. Stable biological control of spider mites occurred after four field seasons, suppressing spider mites to levels similar to those commonly achieved with chemical control. A survey of 11 commercial hop yards in Oregon documented pest and natural enemy densities under commercial management practices over a period of 4 yr (2008-2011). Natural enemy abundance in commercial hop yards was similar to that of a 2- to 3-yr-old hop yard with limited disturbance. Whereas total reliance on biological control for hop aphid is unlikely to be successful, there appears to be unrealized potential for biological control of spider mites in commercial production. Dynamic action thresholds that consider the value of natural enemies are needed for both pests.


Assuntos
Aracnídeos/fisiologia , Biota , Cadeia Alimentar , Insetos/fisiologia , Controle Biológico de Vetores , Animais , Afídeos/fisiologia , Humulus/crescimento & desenvolvimento , Oregon , Distribuição Aleatória , Estações do Ano , Tetranychidae/fisiologia
5.
Plant Dis ; 96(4): 583, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30727434

RESUMO

In June 2009, wilted hop bines were observed in a yard in Marion County, OR. The wilt was associated with a stem rot that occurred ~1 m from the ground near the point where bines are tied together for horticultural purposes. Samples of affected stems were submitted to the Oregon State University Plant Clinic. White hyphae and large, black sclerotia were present on the stems, with a clear delineation between healthy and diseased tissue. The pathogen was identified as Sclerotinia sclerotiorum based on morphological characters. In June 2011, bine wilting was observed on the same farm but in a different hop yard (cv. Nugget) ~10 km from the 2009 occurrence. Affected plants had upward curled leaves with necrotic margins or wilted bines that were severed at the soil line. Wilted bines tended to have smaller diameters than bines with foliar symptoms only. Of 100 plants examined, 75% displayed some foliar symptoms and 66% had at least one bine that was wilted. Yield loss was estimated at 10 to 20% due to bine wilting before cone development. Unlike the 2009 occurrence, wilted bines did not display aerial signs of S. sclerotiorum. Rather, water-soaked lesions covered in white, cottony mycelium were apparent on affected stems 2.5 to 5 cm below the soil surface, some bearing large, irregularly shaped sclerotia. Isolations made onto potato dextrose agar yielded isolates with rapid growth rates and morphological characters consistent with S. sclerotiorum (1). DNA was extracted (2) and pathogen identity was confirmed by PCR amplification and sequencing of the internal transcribed spacer regions from isolates SS001 and SS002 as described before (4). The amplicons were sequenced bidirectionally and consensus sequences were 100% similar to S. sclerotiorum (GenBank No. AAGT01000678.1). Two nucleotide polymorphisms were present that differentiated the sequences from those of 12 S. trifoliorum accessions in GenBank that could be aligned (2). Greenhouse assays utilizing a toothpick inoculation procedure (3) were conducted to fulfill Koch's postulates. Stems of five 4-week-old hop plants of cv. Agate were pierced with a toothpick colonized with S. sclerotiorum. Five control plants were similarly inoculated with toothpicks without the fungus. Inoculated plants developed symptoms similar to those observed in the field within 11 days; four of five plants inoculated with isolate SS001 and two of five plants inoculated with isolate SS002 completely wilted. S. sclerotiorum was reisolated from all inoculated plants but not the control plants. To our knowledge, this is the first report of Sclerotinia wilt on hop in Oregon or the Pacific Northwest (1), where nearly all commercial hop production occurs in the United States. The disease appears to be localized to a limited number of yards, although given the widespread distribution and host range of S. sclerotiorum, it is plausible that the disease may occur in other yards. Recurrent outbreaks and spread of the disease among yards on the affected farm suggests that Sclerotinia wilt has the potential to become a perennial problem on hop and efforts to limit the introduction of S. sclerotiorum into other yards are warranted. References: (1) D. H. Gent. Page 32 in: Compendium of Hop Diseases and Pests. The American Phytopathological Society, St. Paul, MN, 2009. (2) E. N. Njambere et al. Plant Dis. 92:917, 2008. (3) M. L. Putnam. Plant Pathol. 53:252, 2004. (4) T. J. White et al. PCR Protocols: A Guide to Methods and Applications. Academic Press, San Diego, 1990.

6.
J Microsc ; 243(2): 184-96, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21477263

RESUMO

For wool, superior staining of a wide range of ultrastructural components is achieved by en bloc treatment of fibres with a chemical reductant followed by osmium tetroxide. For human scalp hair, although staining quality is similar, the penetration of reagents is poor, resulting in large parts of the fibre cortex remaining unstained. Here we describe a modification to the reduction-osmication method in which reagents penetrate through a cut fibre end, allowing visualization of a wide range of features across the cortex. We compare the staining quality, artefacts and range of structure rendered visible using transmission electron microscopy for en bloc reduction-osmication to other staining alternatives including en bloc silver nitrate and section stains based on uranyl acetate and lead citrate, phosphotungstic acid, potassium permanganate, ammoniacal silver nitrate and some combinations of these stains. The effects of hair-care treatments are briefly examined.


Assuntos
Cabelo/ultraestrutura , Microscopia Eletrônica de Transmissão/métodos , Tetróxido de Ósmio , Coloração e Rotulagem/métodos , Corantes , Feminino , Cabelo/efeitos dos fármacos , Preparações para Cabelo/farmacologia , Técnicas Histológicas , Humanos , Chumbo , Compostos Organometálicos , Oxirredução , Ácido Fosfotúngstico , Permanganato de Potássio , Prata , Nitrato de Prata
7.
Exp Appl Acarol ; 55(4): 401-16, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22020782

RESUMO

The use of synthetic herbivore-induced plant volatiles (HIPV) to attract natural enemies has received interest as a tool to enhance conservation biological control (CBC). Methyl salicylate (MeSA) is a HIPV that is attractive to several key predators of two-spotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae), and hop aphid, Phorodon humuli (Schrank) (Homoptera: Aphididae). A 2-year study was conducted to evaluate the recommended commercial use of MeSA in hop yards in Oregon. Slow-release MeSA dispensers were stapled to supporting poles in 0.5 ha plots and these plots were compared to a paired non-treated plot on each of three farms in 2008 and 2009. Across both years, there was a trend for reduced (range 40-91%) mean seasonal numbers of T. urticae in five of the six MeSA-baited plots. Stethorus spp., key spider mite predators, tended to be more numerous in MeSA-baited plots compared to control plots on a given farm. Mean seasonal densities of hop aphid and other natural enemies (e.g., Orius spp. and Anystis spp.) were similar between MeSA-treated and control plots. Variability among farms in suppression of two-spotted spider mites and attraction of Stethorus spp. suggests that the use of MeSA to enhance CBC of spider mites in commercial hop yards may be influenced by site-specific factors related to the agroecology of individual farms or seasonal effects that require further investigation. The current study also suggests that CBC of hop aphid with MeSA in this environment may be unsatisfactory.


Assuntos
Afídeos , Cannabaceae/parasitologia , Controle de Insetos , Salicilatos/administração & dosagem , Tetranychidae , Animais , Oregon
8.
Environ Entomol ; 48(4): 894-902, 2019 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-31157859

RESUMO

The twospotted spider mite (Tetranychus urticae Koch) is a common pest in agricultural and ornamental crops. This pest can be controlled by resident predatory arthropods in certain situations. This research quantified the stability and resiliency of established conservation biological control of the twospotted spider mite in hop over a 5-yr period associated with nitrogen fertilization rate and use of a broad-spectrum insecticide. Biological control generally was stable and resilient over a sixfold range of nitrogen fertilization rates, and in only 1 of 5 yr did elevated nitrogen rates significantly affect populations of spider mites. In contrast, one application of the insecticide bifenthrin was associated with disruption of biological control and a severe outbreak of spider mites. The complex of natural enemies suppressed the outbreak during the same year in which bifenthrin was applied, but only after populations of spider mites exceeded levels associated with economic damage. However, in the following year the system returned to an equilibrium state where spider mites were suppressed below economically damaging levels. Therefore, conservation biological control in hop appears stable and robust to factors such as nitrogen fertilization that increase reproductive rates of spider mites but may be sensitive to factors such as nonselective insecticides that are lethal to natural enemies. Conservation biological control can be considered resilient to a single use of a nonselective insecticide in the year following the application, but not within the year of application.


Assuntos
Inseticidas , Tetranychidae , Animais , Produtos Agrícolas , Controle Biológico de Vetores
9.
J Econ Entomol ; 111(5): 2499-2502, 2018 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-30085208

RESUMO

Hop looper, Hypena humuli Harris, can cause substantial defoliation and crop damage by feeding on hop leaves and cones. A 4-yr field study conducted in western Oregon evaluated the abundance of hop looper larvae and associated defoliation of leaves on plants fertilized with nitrogen rates ranging from 44.8 to 269 kg/ha. There was annual variation in abundance of hop looper and defoliation, with a tendency for increasing nitrogen rate to increase both abundance of hop looper and defoliation. A mixed model analysis with data combined from 2014 to 2017 found that abundance of hop looper was linearly related to nitrogen fertilizer rate, with a 2.5 increase in hop looper-days per kilogram of nitrogen fertilizer applied. Similarly, based on data from 2015 to 2017, defoliation associated with hop looper increased 0.031 percent with each kilogram of nitrogen fertilizer applied. Therefore, avoiding unduly high rates of nitrogen fertilizer may reduce the abundance and defoliation caused by hop looper. Further studies are needed to understand the mechanisms associated with nitrogen stimulation of hop looper.


Assuntos
Fertilizantes , Herbivoria/efeitos dos fármacos , Humulus , Mariposas , Nitrogênio/administração & dosagem , Animais , Larva
10.
Environ Entomol ; 41(3): 621-35, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22732621

RESUMO

The twospotted spider mite, Tetranychus urticae Koch, is a worldwide pest of numerous agronomic and horticultural plants. Sulfur fungicides are known to induce outbreaks of this pest on several crops, although mechanisms associated with sulfur-induced mite outbreaks are largely unknown. Studies were conducted during 2007-2009 in Oregon and Washington hop yards to evaluate the effect of timing of sulfur applications on T. urticae and key predators. In both regions, applications of sulfur made relatively late in the growing season (mid-June to mid-July) were associated with the greatest exacerbation of spider mite outbreaks, particularly in the upper canopy of the crop. The severity of mite outbreaks was closely associated with sulfur applications made during a relatively narrow time period coincident with the early exponential phase of spider mite increase and rapid host growth. A nonlinear model relating mean cumulative mite days during the time of sulfur sprays to the percent increase in total cumulative mite days (standardized to a nontreated plot) explained 58% of the variability observed in increased spider mite severity related to sulfur spray timing. Spatial patterns of spider mites in the Oregon plots indicated similar dispersal of motile stages of spider mites among leaves treated with sulfur versus nontreated leaves; however, in two of three years, eggs were less aggregated on leaves of sulfur-treated plants, pointing to enhanced dispersal. Apart from one experiment in Washington, relatively few predatory mites were observed during the course of these studies, and sulfur-induced mite outbreaks generally occurred irrespective of predatory mite abundance. Collectively, these studies indicate sulfur induces mite outbreaks through direct or indirect effects on T. urticae, mostly independent of predatory mite abundance or toxicity to these predators. Avoidance of exacerbation of spider mite outbreaks by sulfur sprays was achieved by carefully timing applications to periods of low spider mite abundance and slower host development, which is generally early to mid-spring for hop.


Assuntos
Cadeia Alimentar , Fungicidas Industriais/farmacologia , Enxofre/farmacologia , Tetranychidae/efeitos dos fármacos , Ácaros e Carrapatos/efeitos dos fármacos , Ácaros e Carrapatos/fisiologia , Animais , Ascomicetos/fisiologia , Humulus/crescimento & desenvolvimento , Humulus/microbiologia , Insetos/efeitos dos fármacos , Insetos/fisiologia , Oregon , Doenças das Plantas/prevenção & controle , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/microbiologia , Densidade Demográfica , Estações do Ano , Tetranychidae/fisiologia , Fatores de Tempo , Washington
11.
J Morphol ; 272(1): 34-49, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21061275

RESUMO

We provide a detailed description of the ultrastructure of deer hair fibers. Guard hairs and underhairs from the winter coat of red deer (Cervus elaphus), and antler velvet hairs from the same species were examined. All fibers displayed the typical keratin fiber morphology of overlapping cuticle cells surrounding a core of cortex cells, and often a centrally-located medulla, but there were considerable differences in the diameter, cuticle thickness, and scale pattern, and in the relative amounts of cortex and medulla along individual fibers, and between the different types of fiber. In addition, closer examination of cortex cells using transmission electron microscopy revealed considerable differences in the arrangement of intermediate filaments in the different fiber types. Fine underhairs appeared similar to fine wool fibers from sheep because intermediate filament arrangements were very similar to those found in wool orthocortex cells and paracortex cells. In addition, a similar bilateral distribution of these cell types was evident. However, in the antler velvet hairs and the guard hairs, intermediate filament arrangements were more variable and complex, and showed similarities to those in heterotype cortex cells described for human hair.


Assuntos
Chifres de Veado/anatomia & histologia , Cervos/anatomia & histologia , Cabelo/anatomia & histologia , Animais , Chifres de Veado/ultraestrutura , Cabelo/ultraestrutura , Filamentos Intermediários/ultraestrutura , Microscopia Eletrônica de Transmissão
12.
J Nutr Health Aging ; 13(8): 693-8, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19657552

RESUMO

BACKGROUND: Most studies reporting malnutrition in the elderly relate to high-level care. However, one third of Australians in aged care reside in low-level care facilities. Data is limited on their nutritional status. OBJECTIVE: To investigate the nutritional status of elderly in low-level care facilities. DESIGN: A cross sectional study design. SETTING: 14 low-level aged care facilities in metropolitan Melbourne. PARTICIPANTS: Convenience sample of 103 ambulatory elderly (86 +/- 6.6 years (mean +/- SD), 76% female, comprising 15% of the hostel population) able to perform daily functions of living. MEASUREMENTS: Nutritional intake assessed by three-day weighed food records, and nutritional status by haematological and biochemical markers and body composition (dual energy X-ray absorptiometry). RESULTS: FOOD served did not supply the estimated average requirements (EAR) for 5 of the 14 nutrients analysed. Compared with EAR, 34% of participants were protein malnourished and 62% had energy intake deficits. Micronutrient intake was low for calcium, magnesium, folate, zinc (for men) and dietary fibre. Vitamin D deficiency (serum 25OH Vitamin D < 50 nmol/L) was present in 58% of residents. More men than women had low haemoglobin (P < 0.000), low red blood cells (P < 0.000), and a raised white blood cell count (P = 0.004). Forty three percent of men and 21% women had sarcopenia, 28% of men and 44% women had excess body fat (> 28% and >40%, respectively) and 14% of men and 12 % of women were sarcopenic-obese. Only 12% showed no sign of undernutrition using seven different nutritional indicators. Around 65% had two or more indicators of undernutrition. CONCLUSION: These findings highlight the need for the supply of more, better quality, nutrient dense food to residents and better detection of undernutrition in aged care facilities. Maintenance of nutritional status has the potential to reduce morbidity and delay the transition to high-level care.


Assuntos
Anemia/epidemiologia , Deficiências Nutricionais/epidemiologia , Estado Nutricional , Obesidade/epidemiologia , Desnutrição Proteico-Calórica/epidemiologia , Sarcopenia/epidemiologia , Atividades Cotidianas , Idoso de 80 Anos ou mais , Austrália/epidemiologia , Contagem de Células Sanguíneas , Estudos Transversais , Dieta/normas , Ingestão de Energia , Feminino , Humanos , Institucionalização , Masculino , Micronutrientes/administração & dosagem , Necessidades Nutricionais , Fatores Sexuais , Deficiência de Vitamina D/epidemiologia
13.
Electrophoresis ; 15(7): 972-6, 1994 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7813404

RESUMO

Conventional carrier ampholyte-isoelectric focusing is unsuitable for separating wool and hair proteins. The inability to form stable narrow pH gradients at acidic pH values does not allow good resolution of the many acidic wool and hair proteins. To evaluate the usefulness of immobilised pH gradient-isoelectric focusing (IPG-IEF) for wool proteins, S-amidomethyl wool proteins were analysed using IPG-IEF. Over twenty bands were visible on a pH 4-7 IPG-IEF gel. IPG-IEF was combined with sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) to give a two dimensional separation, and over 50 protein spots were observed. IPG-IEF appears to be ideally suited to the separation of wool proteins. The resolution of two-dimensional electrophoresis using IPG-IEF was greater than previously obtained using acid or alkaline PAGE in the first dimension. Good reproducibility of spot position was observed.


Assuntos
Focalização Isoelétrica/métodos , Proteínas/análise , Lã/química , Misturas Anfolíticas , Animais , Fracionamento Químico , Eletroforese em Gel Bidimensional , Eletroforese em Gel de Poliacrilamida , Cabelo/química , Concentração de Íons de Hidrogênio , Ovinos
14.
Aust J Biol Sci ; 40(1): 1-14, 1987.
Artigo em Inglês | MEDLINE | ID: mdl-3274651

RESUMO

Proteins extracted from the wool of 65 Romney ewes were analysed qualitatively by one- and two-dimensional polyacrylamide gel electrophoresis. Romney wool proteins could be classified into the low-sulfur, high-sulfur, and high-tyrosine protein groups described for wool from other breeds. The wool protein pattern of an individual sheep remained constant despite changes in season, age or nutritional status of the sheep, and did not vary between different body positions. There were between-sheep differences in protein pattern, most variation occurring in the high-sulfur protein group. These differences were presumed to reflect genetic differences between the sheep.


Assuntos
Proteínas/isolamento & purificação , Ovinos/metabolismo , Lã/análise , Animais , Eletroforese em Gel de Poliacrilamida , Feminino , Variação Genética , Peso Molecular , Proteínas/genética , Ovinos/genética
15.
J Biol Chem ; 266(18): 11975-9, 1991 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-2050691

RESUMO

We investigated the properties of an artificial chimeric peptide that contains an Arg-Gly-Asp (RGD)-tripeptide, the versatile cell recognition signal of extracellular matrix protein components, coupled to a carboxyl-terminal fragment of the highly specific alpha-thrombin inhibitor, hirudin (residues 53-64): WGRGDSANGDFEEIPEEYL (RGD-hirudin53-64). Hirudin53-64 and RGD-hirudin53-64 inhibited the fibrinogen clotting activity of alpha-thrombin and prolonged the activated partial thromboplastin time of human plasma. In addition, both peptides afforded total protection to thrombin from trypsionolysis. Neither hirudin53-64 nor RGD-hirudin53-64 dramatically interfered with the thrombin-antithrombin inhibition reaction either in the absence or presence of added heparin. alpha-Thrombin-induced platelet aggregation was effectively inhibited by hirudin53-64 and RGD-hirudin53-64. Unlike hirudin53-64, RGD-hirudin53-64 in solution inhibited integrin-mediated endothelial cell and fibroblast cell attachment to polystyrene wells in the presence of fetal bovine serum. Collectively, our results demonstrate that RGD-hirudin53-64 has anticoagulant/antiplatelet aggregation activity attributable to its hirudin sequence and integrin-directed cell attachment activity due to its RGD site. Our results suggest that this chimeric motif may serve as a prototype for a new class of anticoagulants where an integrin-specific sequence "targets" the peptide to a cell (ultimately through the platelet integrin alpha IIb beta 3) trapped amid a thrombus with ensuing proteinase inhibition.


Assuntos
Antitrombinas/farmacologia , Quimera , Hirudinas/análogos & derivados , Hirudinas/farmacologia , Fragmentos de Peptídeos/farmacologia , Sequência de Aminoácidos , Adesão Celular , Eletroforese em Gel de Poliacrilamida , Heparina/farmacologia , Humanos , Hidrólise , Dados de Sequência Molecular , Agregação Plaquetária/efeitos dos fármacos , Inibidores da Agregação Plaquetária/farmacologia , Trombina/metabolismo , Trombina/farmacologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA