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1.
Hist Cienc Saude Manguinhos ; 28(2): 491-508, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34190791

RESUMO

Oscar Nerval de Gouvêa was a scientist and teacher in Rio de Janeiro, Brazil, whose work spanned engineering, medicine, the social sciences, and law. This paper presents and discusses a manuscript entitled "Table of mineral classification," which he appended to his dissertation Da receptividade mórbida , presented to the Faculty of Medicine in 1889. The foundations and features of the table provide a focus for understanding nineteenth-century mineralogy and its connections in Brazil at that time through this scientist. This text was Gouvêa's contribution to the various mineral classification systems which have emerged from different parts of the world.


Assuntos
Geologia/história , Homeopatia/história , Minerais/história , Brasil , História do Século XVI , História do Século XIX , História do Século XX , História Antiga , Minerais/classificação
2.
Hist. ciênc. saúde-Manguinhos ; 28(2): 491-508, abr.-jun. 2021. graf
Artigo em Inglês | LILACS | ID: biblio-1279139

RESUMO

Abstract Oscar Nerval de Gouvêa was a scientist and teacher in Rio de Janeiro, Brazil, whose work spanned engineering, medicine, the social sciences, and law. This paper presents and discusses a manuscript entitled "Table of mineral classification," which he appended to his dissertation Da receptividade mórbida , presented to the Faculty of Medicine in 1889. The foundations and features of the table provide a focus for understanding nineteenth-century mineralogy and its connections in Brazil at that time through this scientist. This text was Gouvêa's contribution to the various mineral classification systems which have emerged from different parts of the world.


Resumo Oscar Nerval de Gouvêa foi um cientista e professor no Rio de Janeiro, Brasil, cuja obra abrange engenharia, medicina, ciências sociais e direito. Este artigo apresenta e discute o texto intitulado "Tabela de classificação mineral", que ele anexou a sua tese Da receptividade mórbida, apresentada na Escola Superior de Medicina, em 1889. Os fundamentos e características da tabela propiciam a compreensão da mineralogia do século XIX e suas conexões no Brasil à época por intermédio desse cientista. O texto foi a contribuição de Gouvêa aos diversos sistemas de classificação de minerais originados de diferentes partes do mundo.


Assuntos
História do Século XVI , História do Século XIX , História do Século XX , Geologia/história , Homeopatia/história , Minerais/história , Brasil , História Antiga , Minerais/classificação
3.
Poult Sci ; 100(2): 707-720, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33518124

RESUMO

This study was designed to evaluate the effects of green light emitting diode (LED) light during incubation and dietary organic macro and trace minerals during rearing on tibia morphological, biophysical, and mechanical characteristics of broiler chickens at slaughter age. The experiment was setup as a 2 × 2 × 2 factorial arrangement, with the following treatments: 1) light during incubation (green LED light or darkness), 2) macro mineral source during rearing (organic or inorganic Ca and P), and 3) trace mineral source during rearing (organic or inorganic Fe, Cu, Mn, Zn, and Se). A total of 2,400 eggs (Ross 308) were either incubated under green LED light (16L:8D) or in complete darkness. After hatch, a total of 864 male broiler chickens were reared until slaughter age (day 42) and provided with 1 of 4 diets, differing in macro and/or trace mineral source. During rearing, the experiment had a complete randomized block design with 9 replicate pens per treatment and 12 chickens per pen. At slaughter age (day 42), 2 chickens per replicate were randomly selected and tibia bones were obtained. Tibia weight, length, thickness, osseous volume, pore volume, total volume, mineral content, mineral density, ultimate strength, and stiffness were determined. Green LED light during incubation did not affect any of the tibia characteristics. Dietary organic macro minerals positively affected most of the tibia morphological, biophysical, and mechanical characteristics compared to the inorganic macro minerals, whereas trace mineral sources did not affect tibia characteristics. It can be concluded that dietary organic macro minerals Ca and P stimulated tibia characteristics, whereas green LED light during incubation and dietary trace minerals during rearing did not affect tibia characteristics, locomotion, or leg disorders.


Assuntos
Galinhas/fisiologia , Dieta/veterinária , Incubadoras/veterinária , Minerais/administração & dosagem , Tíbia/efeitos da radiação , Oligoelementos/administração & dosagem , Ração Animal/análise , Animais , Galinhas/crescimento & desenvolvimento , Galinhas/metabolismo , Suplementos Nutricionais , Incubadoras/classificação , Masculino , Minerais/classificação , Óvulo , Distribuição Aleatória , Tíbia/diagnóstico por imagem , Tíbia/fisiologia
4.
J Dairy Sci ; 102(11): 9727-9739, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31477292

RESUMO

The aim of this study was to quantify the major sources of variation in the levels of 15 minerals in individual milk samples collected from cows raised in multibreed dairy herds. The herds (n = 27) were classified into 2 categories, according to milk productivity. Milk productivity was based on the net energy of lactating cows' average daily milk yield. Milk samples were collected from 240 cows of 6 different breeds: 3 specialized dairy (Holstein-Friesian, Brown Swiss, and Jersey) and 3 dual-purpose (Simmental, Rendena, and Alpine Grey). The samples were analyzed for macro-elements (Na, Mg, P, S, K, and Ca), essential micro-elements (Mn, Fe, Cu, Zn, and Se), and environmental micro-elements (B, Si, Sr, and Sn), using inductively coupled plasma-optical emission spectrometry. Data were analyzed using a linear mixed model that included fixed effects of days in milk (DIM), parity, breed, and herd productivity, and a random effect of herd-date within productivity level. Results showed that the effect of herd-date varied across minerals. It was especially large for environmental minerals (ranging from 47 to 91% of total variance) and ranged from 11 to 61% for macrominerals and essential microminerals. Milk samples collected from farms with a high level of herd productivity had a richer mineral profile than samples from low-productivity herds. Parity only influenced macrominerals, with the exception of S and Ca, while DIM influenced almost all minerals, with a few exceptions among the environmental elements. Differences in mineral profile were small between specialized and dual-purpose breeds, but they were large within the group of the specialized cows. These breed differences were reduced after adjusting for milk quality and yield, particularly in the case of milk Mg, S, Ca, Mn, and Zn levels. Milk samples from the Jersey and Brown Swiss cows had higher mineral levels (Sn excluded) than milk from the Holstein-Friesian cows; the other breeds of Alpine origin produced milk of intermediate quality. Our findings suggest that breed has a stronger effect on macrominerals and some of the essential microminerals than herd productivity, parity, and DIM. The modification of the mineral profile in milk seems possible for many minerals, but it likely depends on genetics (e.g., breed, selection) and on environmental and management factors in variable proportions according to the mineral considered.


Assuntos
Bovinos/fisiologia , Lactação/fisiologia , Leite/química , Minerais/análise , Animais , Cruzamento , Bovinos/classificação , Indústria de Laticínios/métodos , Fazendas , Feminino , Modelos Lineares , Leite/metabolismo , Minerais/classificação , Paridade , Gravidez
5.
Rev Biol Trop ; 58(2): 733-55, 2010 Jun.
Artigo em Espanhol | MEDLINE | ID: mdl-20527472

RESUMO

Mineral inclusions in plants, of different chemical constitution and forms, have been studied in some plant groups and are currently used as diagnostic tools in taxonomic identifications. With the aim to identify their possible application in taxonomy, mineral inclusions in the leaves of 140 species of Oncidiinae (Orchidaceae) were analyzed and compared. Leave transversal sections were studied with the aid of clear field, phase contrast, and polarized light microscopy. Crystals commonly occured in mesophyll cells, and only in two species those were observed in epidermal cells. Several forms of calcium oxalate crystals and silicdioxide deposits in the form of stegmata were found. The most common crystalline forms were raphides, prisms and druses. Nevertheless, crystals like sands, and concentric and radial plates were also observed in few species. These crystalline forms of concentric and radial plates are reported for the first time in Oncidiinae and Orchidaceae. The stegmata are conical with rough surface, forming tiers along with fibers. Stegmata commonly occur in the vascular bundle sheath and in the abaxial or adaxial fiber bundles. However, few species do not have stegmata in fiber bundles and other species lack both. The taxonomic importance of these mineral inclusions is discussed for the different clades, genera or species within the subtribe Oncidiinae.


Assuntos
Minerais/análise , Orchidaceae/química , Folhas de Planta/química , Minerais/classificação , Orchidaceae/classificação
6.
Rev. biol. trop ; 58(2): 733-755, jun. 2010. ilus, graf, tab
Artigo em Espanhol | LILACS | ID: lil-638037

RESUMO

Diversity of mineral inclusions in the subtribe Oncidiinae (Orchidaceae). Mineral inclusions in plants, of different chemical constitution and forms, have been studied in some plant groups and are currently used as diagnostic tools in taxonomic identifications. With the aim to identify their possible application in taxonomy, mineral inclusions in the leaves of 140 species of Oncidiinae (Orchidaceae) were analyzed and compared. Leave transversal sections were studied with the aid of clear field, phase contrast, and polarized light microscopy. Crystals commonly occured in mesophyll cells, and only in two species those were observed in epidermal cells. Several forms of calcium oxalate crystals and silicdioxide deposits in the form of stegmata were found. The most common crystalline forms were raphides, prisms and druses. Nevertheless, crystals like sands, and concentric and radial plates were also observed in few species. These crystalline forms of concentric and radial plates are reported for the first time in Oncidiinae and Orchidaceae. The stegmata are conical with rough surface, forming tiers along with fibers. Stegmata commonly occur in the vascular bundle sheath and in the abaxial or adaxial fiber bundles. However, few species do not have stegmata in fiber bundles and other species lack both. The taxonomic importance of these mineral inclusions is discussed for the different clades, genera or species within the subtribe Oncidiinae. Rev. Biol. Trop. 58 (2): 733-755. Epub 2010 June 02.


Las inclusiones minerales en las plantas, han sido utilizadas como herramientas de diagnóstico en la identificación taxonómica. Se analizaron y compararon las inclusiones minerales en las hojas de 140 especies de Oncidiinae (Epidendroideae: Orchidaceae). Las secciones transversales de hojas se observaron para describir las inclusiones minerales con el apoyo de la microscopía de luz en campo claro, contraste de fases y polarización. Los cristales generalmente están presentes en las células del mesófilo, y sólo dos especies los presentan en las células epidérmicas. Se encontraron cristales de oxalato de calcio de diferentes formas y depósitos de dióxido de sílice en forma de estégmatos. Las formas cristalinas más comunes son rafidios, prismas y drusas. Sin embargo, algunas especies tienen cristales en arena, concéntricos o en placas radiales. En esta investigación se reportan las dos últimas por primera vez para Oncidiinae y también para Orchidaceae. Los estégmatos son cónicos con superficie rugosa, generalmente formando hileras a lo largo de las fibras. Comúnmente se presentan en los haces vasculares y en los haces de fibras abaxiales. Sin embargo, existen especies cuyos haces de fibras no tienen estégmatos, así como especies sin haces de fibras ni estégmatos. Se discute la importancia taxonómica de estas inclusiones minerales para los diferentes clados, géneros y/o especies de Oncidiinae.


Assuntos
Minerais/análise , Orchidaceae/química , Folhas de Planta/química , Minerais/classificação , Orchidaceae/classificação
7.
Ann Occup Hyg ; 54(2): 204-16, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19955327

RESUMO

A range of industrial minerals was tested using the rotating drum and the continuous drop methods, the two methods proposed by the published European standard EN 15051 [CEN. (2006) EN 15051 Workplace atmospheres-measurement of the dustiness of bulk materials-requirements and test methods. Brussels, Belgium: European Committee for Standardization], to evaluate and compare their dustiness. The assessment of bulk materials dustiness can help to develop less dusty products and to reduce dust exposure to the workers by improving the processing of minerals. The European standard EN 15051 (CEN, 2006) proposes a classification system that was developed with the intention to assist in the labelling of products in the future. This paper presents a comparison of both test methods in classifying industrial minerals. The correlation between the dustiness measured by the two methods for the inhalable and respirable fractions is given. The results show there is no unambiguous dependence of the dustiness on the grain size of an industrial mineral. Although dustiness can significantly be affected by product moisture, the influence of this parameter is not studied in detail as the industrial minerals were tested in the conditions they are sold, as the standard requires. Especially, the classification of substances with respect to different classes of dustiness was found to be problematic, as the two methods are by no means yielding identical classification groups for all the substances. In any use of the standard (EN 15051; CEN, 2006) for labelling purposes, a revision of the present classification system provided in the standard is required for industrial minerals.


Assuntos
Poluentes Ocupacionais do Ar/análise , Poeira/análise , Indústrias , Minerais/classificação , Exposição Ocupacional/análise , Monitoramento Ambiental/métodos , Monitoramento Ambiental/normas , União Europeia , Humanos , Exposição por Inalação/análise , Minerais/análise , Minerais/normas , Exposição Ocupacional/normas
8.
Ann Bot ; 104(1): 91-113, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19429923

RESUMO

BACKGROUND AND AIMS: There are no descriptions of phytoliths produced by plants from the 'Zambezian' zone, where Miombo woodlands are the dominant element of the largest single phytochorion in sub-Saharan Africa. The preservation of phytoliths in fossil records of Africa makes phytoliths a tool to study early plant communities. Paleo-ethnobotanical interpretation of phytoliths relies on the comparison of ancient types with morphotypes extracted from living reference collections. METHODS: Phytoliths were extracted from plant samples representing 41 families, 77 genera and 90 species through sonic cleaning, dry ashing and acid treatment; and phytoliths thus extracted were quantified. For each species, an average of 216 phytoliths were counted. The percentage of each morphotype identified per species was calculated, and types were described according to the descriptors from the International Code for Phytolith Nomenclature. Phytolith assemblages were subject to discriminant analysis, cluster analysis and principal component analysis. KEY RESULTS: Phytoliths were grouped into 57 morphotypes (two were articulated forms and 55 were discrete shapes), and provide a reference collection of phytolith assemblages produced by Miombo woody species. Common and unique morphotypes are described and taxonomic and grouping variables are looked into from a statistical perspective. CONCLUSIONS: The first quantitative taxonomy of phytoliths from Miombos is presented here, including new types and constituting the most extensive phytolith key for any African ecoregion. Evidence is presented that local woody species are hypervariable silica producers and their phytolith morphotypes are highly polymorphic. The taxonomic significance of these phytoliths is largely poor, but there are important exceptions that include the morphotypes produced by members from >10 families and orders. The typical phytolithic signal that would allow scientists to identify ancient woodlands of 'Zambezian' affiliation comprises only half of the original number of phytoliths originally produced and might favour the more resilient blocky, cylindroid, globular and tabular forms.


Assuntos
Minerais/química , Plantas/química , Dióxido de Silício/química , África , Análise por Conglomerados , Análise Discriminante , Geografia , Minerais/classificação , Moçambique , Análise de Componente Principal , Dióxido de Silício/classificação
9.
Spectrochim Acta A Mol Biomol Spectrosc ; 71(5): 1788-94, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18691936

RESUMO

Raman spectroscopy complimented with infrared spectroscopy has been used to determine the molecular structure of the roselite arsenate minerals of the roselite and fairfieldite subgroups of formula Ca(2)B(AsO(4))(2).2H(2)O (where B may be Co, Fe(2+), Mg, Mn, Ni and Zn). The Raman arsenate (AsO(4))(2-) stretching region shows strong differences between the roselite arsenate minerals which is attributed to the cation substitution for calcium in the structure. In the infrared spectra complexity exists with multiple (AsO(4))(2-) antisymmetric stretching vibrations observed, indicating a reduction of the tetrahedral symmetry. This loss of degeneracy is also reflected in the bending modes. Strong Raman bands around 450 cm(-1) are assigned to nu(4) bending modes. Multiple bands in the 300-350 cm(-1) region assigned to nu(2) bending modes provide evidence of symmetry reduction of the arsenate anion. Three broad bands for roselite are found at 3450, 3208 and 3042 cm(-1) and are assigned to OH stretching bands. By using a Libowitzky empirical equation hydrogen bond distances of 2.75 and 2.67 A are estimated. Vibrational spectra enable the molecular structure of the roselite minerals to be determined and whilst similarities exist in the spectral patterns, sufficient differences exist to be able to determine the identification of the minerals.


Assuntos
Arseniatos/química , Minerais/química , Arseniatos/classificação , Ligação de Hidrogênio , Hidróxidos/química , Minerais/classificação , Espectrofotometria Infravermelho , Análise Espectral Raman
10.
J Environ Monit ; 11(7): 1428-32, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20449234

RESUMO

The Rover Environmental Monitoring Station (REMS) is one of NASA/MSL's instruments, which has been designed for measuring ambient pressure, humidity, wind speed and direction, UV radiation, and air and ground temperature (GT). The GT-sensor is dedicated to measure the real temperature of the Martian surface, integrating the IR energy coming from the ground. The existing IR spectral data of Martian dust, rocks and sediments allow for comparing the Martian spectra with the spectra of different terrestrial minerals and lithologies, and those of their alteration and weathering products. The FTIR reflectance of a set of selected astrobiologically significant minerals (including oxides, oxi/hydroxides, sulfates, chlorides, opal and clays) and basalt (as the main and most widespread volcanic Martian rock) was measured, considering different mixing amounts, and covering the specific working wavelength range of the REMS' GT-sensor. The results obtained show important percentage increases or decreases of reflectance in the entire wavelength range (e.g. basalt-hematite vs. basalt-magnetite) and specific variations limited to some spectral bands (e.g. basalt-smectite vs. basalt-jasper). The basalt reflectance percentage increases or decreases, even up to 100%, depending on the mixing of the different minerals. This unequivocally confirms the need for considering the chemical-mineralogical assemblages (and their textures) for any investigation and interpretation of Mars surface environment. Some complementary applications of this research on our planet, either in relation to the specific performances and characteristics of the GT-sensor autonomous recalibration system, or those oriented to carrying out similar studies on different types of terrestrial environmental settings, are also described.


Assuntos
Meio Ambiente Extraterreno/química , Fenômenos Geológicos , Marte , Minerais/análise , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Movimentos do Ar , Cloretos , Exobiologia/métodos , Umidade , Minerais/química , Minerais/classificação , Óxidos , Pressão , Silicatos , Espectroscopia de Infravermelho com Transformada de Fourier/instrumentação , Sulfatos , Raios Ultravioleta , Estados Unidos , United States National Aeronautics and Space Administration
11.
Microsc Res Tech ; 70(11): 960-8, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17661389

RESUMO

Microscopic authentication is an effective method for quality control of Chinese Materia Medica (CMM) because of its speed, convenience and low cost. However, the application of modern microscopic technique in quality evaluation of Toxic and Potent Chinese Materia Medica (T/PCMM) of animal origin is seldom reported. This gap in published knowledge is increasingly serious because confusion in T/PCMM has led to serious medical problems in China and other countries in recent years. To ensure the safe and effective use of T/PCMM, an accurate and convenient method, based on macroscopic and microscopic techniques, was developed for the authentication of animal T/PCMM. The color microscopic photos of the crude drug were acquired with the light microscope, and from these their morphological and microscopic characters were described. The present method was successfully applied in the analysis of 31 T/PCMM including 17 samples originating from plants, 3 from animals, 9 from minerals, and the remaining 2 from secreta. The macro- and microscopic characters of three animal T/PCMM, namely Mylabris (Mylabris phalerata or Mylabris cichorii), Huechys (Huechys sanguinea), and Lytta (Lytta caraganae) were conclusively determined and are here presented. The results demonstrated that it was feasible to use the present microscopic characters for the authentication of the above three animal T/PCMM.


Assuntos
Medicamentos de Ervas Chinesas/química , Materia Medica/química , Minerais/química , Animais , Medicamentos de Ervas Chinesas/classificação , Medicamentos de Ervas Chinesas/toxicidade , Insetos/classificação , Insetos/ultraestrutura , Microscopia , Minerais/classificação
12.
Pediátrika (Madr.) ; 24(3): 67-79, mar. 2004. tab
Artigo em Es | IBECS | ID: ibc-31512

RESUMO

El objetivo de este trabajo es dar una información complementaria, con la finalidad de precisar los conocimientos sobre la mayoría de los nutrientes esenciales. Se revisa el papel fisiológico, metabolismo, deficiencias y los requerimientos de las vitaminas, minerales y oligoelementos. Definir los límites de tolerancias para aquellas vitaminas y minerales en las cuales el exceso es un problema (AU)


Assuntos
Adolescente , Adulto , Idoso , Feminino , Pré-Escolar , Lactente , Masculino , Pessoa de Meia-Idade , Criança , Humanos , Recém-Nascido , Micronutrientes/metabolismo , Micronutrientes/classificação , Vitaminas Lipossolúveis , Vitaminas Hidrossolúveis , Minerais/metabolismo , Minerais/classificação , Espanha
13.
Spectrochim Acta A Mol Biomol Spectrosc ; 59(10): 2247-66, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12909139

RESUMO

Small catalogues of reference Raman spectra of interest for analysing geomaterials or biomaterials of relevance to art history or archaeology are gradually being published by different research groups. However, except for some older catalogues, they are all concerned primarily with pigments, whether inorganic or organic. Here we present for the first time a catalogue of Raman spectra of minerals that may be found in corroded metal artworks or artefacts. At the same time we include some inorganic pigments that may be found in or on stained glass. Most of the minerals analysed came from the Gallery of Mineralogy at the Muséum National d'Histoire Naturelle and most were verified by X-ray diffraction in order to augment the confidence in the mineral identity (which is not the case with many other catalogues). A number of problems encountered with mineral terminology are discussed. Comments are made on the spectra where appropriate.


Assuntos
Corantes/química , Vidro/química , Metais/química , Minerais/química , Arqueologia , Arte , Corrosão , Minerais/classificação , Análise Espectral Raman
15.
Urology ; 61(6): 1092-6; discussion 1097, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12809867

RESUMO

OBJECTIVES: To measure, in an in vitro study, the number of shock waves to complete comminution for 195 human stones, representing six major stone types. Not all renal calculi are easily broken with shock wave lithotripsy. Different types of stones are thought to have characteristic fragilities, and suggestions have been made in published reports of variation in the fragility within some types of stones, but few quantitative data are available. METHODS: Kidney stones classified by their dominant mineral content were broken in an unmodified Dornier HM3 lithotripter or in a research lithotripter modeled after the HM3, and the number of shock waves was counted for each stone until all fragments passed through a sieve (3-mm-round or 2-mm-square holes). RESULTS: The mean +/- SD number of shock waves to complete comminution was 400 +/- 333 per gram (n = 39) for uric acid; 965 +/- 900 per gram (n = 75) for calcium oxalate monohydrate; 1134 +/- 770 per gram (n = 21) for hydroxyapatite; 1138 +/- 746 per gram (n = 13) for struvite; 1681 +/- 1363 per gram (n = 23) for brushite; and 5937 +/- 6190 per gram (n = 24) for cystine. The variation for these natural stones (83% +/- 15% coefficient of variation) was greater than that for artificial (eg, gypsum-based) stones (17% +/- 8%). CONCLUSIONS: The variability in stone fragility to shock waves is large, even within groups defined by mineral composition. Thus, knowing the major composition of a stone may not allow adequate prediction of its fragility in lithotripsy treatment. The variation in stone structure could underlie the variation in stone fragility within type, but testing of this hypothesis remains to be done.


Assuntos
Cálculos Renais/química , Litotripsia/métodos , Humanos , Cálculos Renais/classificação , Minerais/química , Minerais/classificação
16.
Public Health Nutr ; 6(3): 281-91, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12740077

RESUMO

OBJECTIVE: To describe how a risk analysis can be applied to food fortification, with emphasis on voluntary fortification and intake levels that might exceed usual dietary levels. DESIGN: Use of the risk analysis model as a frame to classify nutrients according to the risk of exceeding upper safe intake levels. Furthermore, to apply the model when discussing possible consequences of liberal fortification practices on eating behaviour and disease patterns. SETTING: The discussion on food fortification presently going on internationally. RESULTS: Micronutrients can be classified according to their safety margin, i.e. the size of the interval between the recommended intake and the upper safe level of intake. We suggest that nutrients with a small safety margin, i.e. for which the upper safe level is less than five times the recommended intake, be placed in a category A and should be handled with care (retinol, vitamin D, niacin, folate and all minerals). Category B comprises nutrients with an intermediate safety margin (vitamins E, B6, B12 and C), while nutrients that according to present knowledge are harmless even at 100 times the recommendation (vitamin K, thiamin, riboflavin, pantothenic acid and biotin) are categorised as C. DISCUSSION: The risk analysis model is a useful tool when assessing the risk of both too low and excess intakes of single micronutrients, but can also be applied to analyse the consequences of fortification practices on eating behaviour and disease patterns. Liberal fortification regulations may, for example, distort the conception of what is healthy food, and drive consumption towards a more unhealthy diet, contributing to the plague of overweight and concomitant increased risk of degenerative diseases. CONCLUSION: The impact of fortification practices on the total eating pattern of a population should become an integrated part of the discussions and regulations connected to the issue.


Assuntos
Alimentos Fortificados/efeitos adversos , Micronutrientes/administração & dosagem , Minerais/administração & dosagem , Vitaminas/administração & dosagem , Humanos , Micronutrientes/efeitos adversos , Micronutrientes/classificação , Minerais/efeitos adversos , Minerais/classificação , Modelos Teóricos , Política Nutricional , Necessidades Nutricionais , Medição de Risco , Fatores de Risco , Vitaminas/efeitos adversos , Vitaminas/classificação
17.
Cancer Epidemiol Biomarkers Prev ; 12(2): 84-9, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12582016

RESUMO

The insulin-like growth factor (IGF) axis may play opposing roles in health and disease. The age-related declines in growth hormone and IGF-I may be associated with potentially deleterious changes in body composition and functioning, but recent studies suggest that IGF-I levels may be related to risk of prostate, colorectal, premenopausal breast, and possibly other cancers. Thus, we studied dietary influences on plasma IGF-I and IGF-I:IGF-binding protein-3 ratio in 753 men in the Health Professionals Follow-Up Study who completed a food frequency questionnaire. In this generally well-nourished population of middle-aged to elderly men, plasma IGF-I and IGF-I:IGF-binding protein-3 molar ratio tended to increase with higher intake of protein and minerals, including potassium, zinc, magnesium, calcium, and phosphorus. Men with relatively high intakes of total protein (top quintile) and minerals (top quintile of the five minerals combined) had a 25% higher mean plasma level of IGF-I compared with those in the low quintiles simultaneously. The major sources of animal protein, including milk, fish, and poultry, but not red meat, as well as total vegetable protein, were associated with an increase in IGF-I levels. Energy intake was positively related to plasma IGF-I level but only in men with body mass index <25 kg/m(2). The age-related decline in plasma IGF-I may be exacerbated by low intakes of protein and minerals. The potential role of these dietary factors on cancer risk through altering IGF-I levels requires study.


Assuntos
Fator de Crescimento Insulin-Like I/metabolismo , Neoplasias/sangue , Neoplasias/dietoterapia , Estado Nutricional/fisiologia , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/sangue , Índice de Massa Corporal , Estudos Transversais , Proteínas Alimentares/administração & dosagem , Proteínas Alimentares/classificação , Ingestão de Energia , Seguimentos , Pessoal de Saúde , Humanos , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/sangue , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/efeitos dos fármacos , Fator de Crescimento Insulin-Like I/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Minerais/administração & dosagem , Minerais/classificação , Análise Multivariada , Valor Preditivo dos Testes , Estudos Prospectivos , Estatística como Assunto , Estados Unidos/epidemiologia , Vitaminas/administração & dosagem , Vitaminas/classificação
18.
J Ethnopharmacol ; 80(2-3): 167-79, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-12007707

RESUMO

This article presents the results of a study of the medicinal uses of natural substances in medieval and Ottoman al-Sham (the Levant). It involved a meticulous survey of a wide range of historical sources spanning approximately 1100 years and including medical and pharmacological literature, travelogues, geographical and agricultural literature, dictionaries, archives, the Genizah and other medieval sources. Our main goal was to arrive at a reconstruction of the unwritten materia medica of the medieval and Ottoman Levant. Of the many and varied medicinal substances on which we were able to extract information, we were able to identify 286. These are presented according to the following classification: 234 species of plants (81.8%); 27 species of animals (9.5%); 15 kinds of minerals (5.2%) and 10 substances of other or mixed origin (3.5%). Analysis of the data showed that the region under study served as the geographic origin of the majority of the substances, only a minority of the materials was imported. The main reason for this is the geographic location of the Levant as a junction between three continents, as a cultural meeting point and as trade center. Finally, our data revealed that the al-Sham region was an independent source of production and marketing of medicinal substances during the medieval and Ottoman periods.


Assuntos
Materia Medica/história , Animais , História do Século XV , História do Século XVI , História do Século XVII , História do Século XVIII , História Medieval , Materia Medica/classificação , Medicina Tradicional/história , Oriente Médio , Minerais/classificação , Minerais/história , Plantas Medicinais/classificação
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