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1.
Ambio ; 47(8): 893-907, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29549601

RESUMO

Iron mining activities in the Bruche valley (Vosges Mountains, France) date historically from the Roman period to the mid-nineteenth century. The geochemical and palynological study of a core from the peat bog of Le Champ du Feu allows highlighting impacts of these activities over the past millennium. Trace metal contamination is recorded for lead (Pb), arsenic, zinc, and antimony during the Middle Ages, the sixteenth century, and from cal. AD 1750-1900, with several sources distinguished by Pb isotope analyses. Forest exploitation is attested by the palynological analysis of the core, with exploitation of Fagus for smelting processes and cutting of Abies for agro-pastoralism. This approach highlights several patterns of contamination, corresponding to the mixing sources and the contamination intensity, which can be linked to the pollen assemblage zones. Hence, anthropogenic activities such as mining and farming led to long-term modification of the landscape composition in this mountainous area.


Assuntos
Conservação dos Recursos Naturais/história , Poluição Ambiental/história , Florestas , Pradaria , Chumbo/história , Mineração/história , Poluentes do Solo/história , Zinco/história , Antimônio/efeitos adversos , Antimônio/análise , Antimônio/história , Arsênio/efeitos adversos , Arsênio/análise , Arsênio/história , França , História do Século XV , História do Século XVI , História do Século XVII , História do Século XVIII , História do Século XIX , História do Século XX , História Medieval , Humanos , Ferro/efeitos adversos , Ferro/história , Chumbo/efeitos adversos , Chumbo/análise , Mineração/tendências , Modelos Teóricos , Poluentes do Solo/efeitos adversos , Espectrometria gama , Zinco/efeitos adversos , Zinco/análise
3.
Ambix ; 61(3): 299-304, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25276876

RESUMO

Sometime during the 1920s, Cardiff Public Libraries (later to become Cardiff Central Library) acquired a six-volume handwritten manuscript collection entitled Mineral & Chemical History of Iron. The author of the manuscripts is named as William Lewis. Now uniformly bound in half-leather and cloth boards, this impressive holding provides, in more than a thousand handwritten pages, an early attempt to produce a full-scale treatise in English on the history of iron.' This note traces the route by which the collection reached Cardiff, and also presents evidence for the existence of a hitherto unknown work on the history of brass by the same author.


Assuntos
Cobre/história , Ferro/química , Ferro/história , Manuscritos como Assunto/história , Zinco/história , Cobre/química , História do Século XVIII , Zinco/química
4.
Neurology ; 82(13): 1175-9, 2014 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-24688096

RESUMO

Zinc-induced myeloneuropathy was recently (re)discovered and its pathophysiology elaborated as resulting from secondary copper deficiency. However, myelopathy was a recognized problem among European zinc-smelter workers in the late 19th century, although these early reports have been overlooked in recent studies and reports. The purpose of this article is to translate and review German-language reports of myelopathy among zinc-smelter workers in Upper Silesia (now southern Poland) by Schlockow from the 1870s. Disease manifestations among zinc-smelter workers developed after sustained zinc exposure over many years. The earliest symptoms were sensory and included paresthesias, dysesthesias, allodynia, and formication in the lower extremities, particularly the feet. Workers ultimately developed a clinical picture resembling subacute combined degeneration of the spinal cord with a spastic-ataxic gait with prominent proprioceptive impairment, sensory disequilibrium, and rombergism.


Assuntos
Indústria Química/história , Exposição Ocupacional/história , Doenças da Medula Espinal/induzido quimicamente , Doenças da Medula Espinal/história , Zinco/história , Zinco/toxicidade , História do Século XIX , Humanos , Exposição Ocupacional/prevenção & controle , Polônia , Doenças da Medula Espinal/diagnóstico
5.
Adv Nutr ; 3(6): 772-82, 2012 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-23153731

RESUMO

Dietary components influencing zinc (Zn) bioavailability were implicated in the first cases of human Zn deficiency in the Middle East in the 1960s. It was not until the 1980s that isotope tracer studies in humans quantified the effects of the type and/or quantity of Zn, protein, iron, and phytate (myo-inositol hexaphosphate) on Zn absorption in humans and confirmed the dose-dependent inhibitory effect of phytate on Zn absorption. This led to further analysis of the Zn and phytate content of foods. The use of phytate-to-Zn molar ratios as likely estimates of absorbable dietary Zn followed together with an assessment of their relationship with Zn biomarkers in low-income countries (LIC). In the 1990s, increasing knowledge of factors governing Zn-absorption diets led to refinements of Zn requirements and algorithms to estimate dietary Zn bioavailability. Their use highlighted that inadequate Zn intake from plant-based diets were a major etiological factor in morbidity and stunting in LIC, prompting the need to identify indicators of the population's Zn status. Major advances in analyses of dietary data pioneered by Beaton in 1980s led to the endorsement in 2007 of a dietary Zn indicator based on the prevalence of the population with usual Zn intake below the estimated average requirement for Zn. Risk of Zn deficiency is a public health concern when the prevalence of inadequate Zn intake is >25%. Recent findings that Zn bioavailability from high-phytate, whole-day diets is lower than previous estimates suggest that revision of Zn estimated average requirement for LIC may be warranted.


Assuntos
Dieta , Avaliação Nutricional , Necessidades Nutricionais , Estado Nutricional , Ácido Fítico/efeitos adversos , Oligoelementos/deficiência , Zinco/deficiência , Disponibilidade Biológica , Dieta/história , História do Século XX , História do Século XXI , Humanos , Ácido Fítico/história , Oligoelementos/administração & dosagem , Oligoelementos/história , Oligoelementos/metabolismo , Zinco/administração & dosagem , Zinco/história , Zinco/metabolismo
6.
Adv Nutr ; 3(6): 783-9, 2012 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-23153732

RESUMO

Zinc was established as essential for green plants in 1926 and for mammals in 1934. However, >20 y would pass before the first descriptions of zinc deficiencies in farm animals appeared. In 1955, it was reported that zinc supplementation would cure parakeratosis in swine. In 1958, it was reported that zinc deficiency induced poor growth, leg abnormalities, poor feathering, and parakeratosis in chicks. In the 1960s, zinc supplementation was found to alleviate parakeratosis in grazing cattle and sheep. Within 35 y, it was established that nearly one half of the soils in the world may be zinc deficient, causing decreased plant zinc content and production that can be prevented by zinc fertilization. In many of these areas, zinc deficiency is prevented in grazing livestock by zinc fertilization of pastures or by providing salt licks. For livestock under more defined conditions, such as poultry, swine, and dairy and finishing cattle, feeds are easily supplemented with zinc salts to prevent deficiency. Today, the causes and consequences of zinc deficiency and methods and effects of overcoming the deficiency are well established for agriculture. The history of zinc in agriculture is an outstanding demonstration of the translation of research into practical application.


Assuntos
Agricultura , Ração Animal , Deficiências Nutricionais/prevenção & controle , Oligoelementos/deficiência , Zinco/deficiência , Agricultura/história , Animais , Animais Domésticos , Deficiências Nutricionais/complicações , Deficiências Nutricionais/história , Deficiências Nutricionais/veterinária , Transtornos do Crescimento/etiologia , Transtornos do Crescimento/história , Transtornos do Crescimento/veterinária , História do Século XX , História do Século XXI , Humanos , Paraceratose/etiologia , Paraceratose/história , Paraceratose/veterinária , Oligoelementos/história , Oligoelementos/uso terapêutico , Zinco/história , Zinco/uso terapêutico
8.
J Inorg Biochem ; 111: 100-3, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22855948

RESUMO

The enlightened formation, by Bert and Kuggie Vallee, of a procedure whereby senior scientists spend short time of about a month at Harvard, Oxford and other institutions, is illustrated by the views and opinions of those selected.


Assuntos
Química Bioinorgânica/história , Intercâmbio Educacional Internacional/história , Metaloproteínas/história , Zinco/história , História do Século XX , História do Século XXI , Estados Unidos
10.
Environ Pollut ; 162: 294-302, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22243877

RESUMO

Predicting the transfer of contaminants in soils is often hampered by lacking validation of mathematical models. Here, we applied Hydrus-2D software to three agricultural soils for simulating the 1900-2005 changes of zinc and lead concentration profiles derived from industrial atmospheric deposition, to validate the tested models with plausible assumptions on past metal inputs to reach the 2005 situation. The models were set with data from previous studies on the geochemical background, estimated temporal metal deposition, and the 2005 metal distributions. Different hypotheses of chemical reactions of metals with the soil solution were examined: 100% equilibrium or partial equilibrium, parameterized following kinetic chemical extractions. Finally, a two-site model with kinetic constant values adjusted at 1% of EDTA extraction parameters satisfactory predicted changes in metal concentration profiles for two arable soils. For a grassland soil however, this model showed limited applicability by ignoring the role of earthworm activity in metal incorporation.


Assuntos
Chumbo/química , Metalurgia , Poluentes do Solo/química , Zinco/química , Agricultura , Monitoramento Ambiental , História do Século XX , História do Século XXI , Cinética , Chumbo/história , Modelos Teóricos , Poluentes do Solo/história , Zinco/história
11.
Rev. cuba. hematol. inmunol. hemoter ; 27(4): 367-381, oct.-dic. 2011.
Artigo em Espanhol | LILACS | ID: lil-615367

RESUMO

El zinc es un elemento químico situado en el grupo 12 de la tabla periódica; es un metal clasificado como de transición. Desde el punto de vista biológico es un constituyente de más de 300 metaloproteínas y de más de 2 000 factores de transcripción. Su participación en el metabolismo abarca una amplia variedad de reacciones, tanto de síntesis como de degradación de casi todas las biomoléculas. La ingesta diaria recomendada está calculada entre 10 y 20 mg. Es muy abundante en las carnes rojas, mariscos, germen de los cereales y leche. Se encuentra prácticamente en la totalidad de las células, aunque el 90 por ciento del zinc total del organismo está contenido en el músculo esquelético y los huesos. Se destaca la inexistencia de reservas y sus niveles están bajo estricto control homeostático. Por su función inmunomoduladora ha sido utilizado clínicamente en las infecciones respiratorias agudas pediátricas y en la recuperación del sistema inmune de los niños desnutridos. Se ha empleado en las enfermedades diarreicas agudas como estabilizador del epitelio intestinal y las membranas, así como protector de la peroxidación lipídica. Otra de sus acciones es mejorar la cicatrización, por lo que ha sido utilizado en las úlceras de miembros inferiores, asociadas con enfermedad venosa y en el pie diabético, donde se combina su efecto cicatrizante con el de estimulador de la inmunidad celular. Algunos desórdenes cutáneos como las verrugas vulgares, han sido tratados con zinc. No se han encontrado trabajos que relacionen al zinc directamente con el paciente inmunodeficiente


Zinc is a chemical element located in group 12 of the periodic table; it is classified as a transition metal. From the biological point of view, it is a constituent of more than 300 metalloproteins and more than 2 000 transcription factors. Its participation in metabolism encompasses a wide variety of reactions, both synthesis and degradation of almost all biomolecules. The recommended daily intake is estimated to be between 10 and 20 mg. It is very abundant in red meat, seafood, germ of cereal and milk. It is found in virtually all cells, although 90 percent of total body zinc is contained in skeletal muscle and bone. It highlights the lack of reserves and their levels are under tight homeostatic control. Due to its immune modulatory function, it has been clinically used in pediatric acute respiratory infections and immune system recovery of malnourished children. It has been used in acute diarrheal disease as a stabilizer of intestinal epithelium and membranes, as well as lipid peroxidation protector. Another of its actions is to improve healing, so it has been used in lower limb ulcers associated with venous disease and diabetic foot, which is combined its healing effect with its stimulating cellular immunity. Some skin disorders such as common warts have been treated with zinc. No papers directly relating zinc with immune compromised patient were found


Assuntos
Zinco/história , Zinco , Zinco/uso terapêutico , Sistema Imunitário
14.
Chemosphere ; 75(4): 442-6, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19201441

RESUMO

An integrated analysis has been carried out on two cores dated by combination of (210)Pb and (137)Cs in order to characterize the extent of heavy metal accumulation in the Liaodong Bay, Northern China. The concentrations and burial fluxes of Zn, Pb, Cd, and Hg increased abruptly after late 1970s. The enrichment factors of Cd, Hg, Zn and Pb are more than 30, 10, 7, and 3.5, respectively, in the surface sediments. Coincident to the increase of heavy metal contents, the decreasing trend of (206)Pb/(207)Pb ratio indicated lead in the surface sediments mainly come from anthropogenic activities.


Assuntos
Sedimentos Geológicos/análise , Metais Pesados/análise , Poluentes da Água/análise , Cádmio/análise , Cádmio/história , China , Monitoramento Ambiental , História do Século XIX , História do Século XX , Chumbo/análise , Chumbo/história , Radioisótopos de Chumbo/análise , Mercúrio/análise , Mercúrio/história , Metais Pesados/história , Oceanos e Mares , Fatores de Tempo , Poluentes da Água/história , Zinco/análise , Zinco/história
15.
J Am Coll Nutr ; 28(3): 257-65, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20150599

RESUMO

The essentiality of zinc was recognized 46 years ago. Zinc deficiency resulting in growth retardation, hypogonadism, immune dysfunction and cognitive impairment affects nearly 2 billion subjects in the developing world. High phytate content of the cereal proteins consumed in the developing world, results in decreased availability of zinc for absorption. Zinc therapy has been very successful and life saving measure in patients with acrodermatitis enteropathica and Wilson's disease. Beneficial therapeutic responses of zinc supplementation have been ovserved in acute diarrhea in children, chronic hepatitis C, shigellosis, leprosy, leishmaniasis, and common cold. Zinc supplementation was effective in decreasing incidences of infection in elderly and patients with sickle cell disease. Zinc supplementation was effective in preventing blindness in 25% of the elderly with dry type of age related macular degeneration. Zinc supplementation in the elderly decreased oxidative stress and decreased generation of inflammatory cytokines. Zinc is an intracellular signaling molecule in monocytes, dendritic cells and macrophages and it plays an important role in cell-mediated immune functions and oxidative stress. Zinc is also an anti-inflammatory agent. These unique properties of zinc may have significant therapeutic benefits in several diseases in humans. In many diseases concurrent zinc deficiency may complicate the clinical features, affect adversely immunological status, increase oxidative stress and increase generation of inflammatory cytokines. Oxidative stress and chronic inflammation may play important causative roles in many chronic diseases, including atherosclerosis, several malignancies, neurological disorders, and auto-immune diseases. It is therefore, important that status of zinc is assessed and zinc deficiency corrected in these chronic diseases. A controlled clinical trial of zinc supplementation in these disorders in order to document the preventive and therapeutic effects of zinc is warranted.


Assuntos
Suplementos Nutricionais , Zinco/deficiência , Zinco/uso terapêutico , Deficiência de Vitaminas/história , Degeneração Hepatolenticular/tratamento farmacológico , Degeneração Hepatolenticular/história , História do Século XX , História do Século XXI , Humanos , Zinco/história , Zinco/farmacologia
19.
J Nutr ; 130(2S Suppl): 496S-502S, 2000 02.
Artigo em Inglês | MEDLINE | ID: mdl-10721938

RESUMO

Zinc (Zn) is essential for synthesis of coenzymes that mediate biogenic-amine synthesis and metabolism. Zn from vesicles in presynaptic terminals of certain glutaminergic neurons modulates postsynaptic N-methyl-D-aspartate (NMDA) receptors for glutamate. Large amounts of Zn released from vesicles by seizures or ischemia can kill postsynaptic neurons. Acute Zn deficiency impairs brain function of experimental animals and humans. Zn deficiency in experimental animals during early brain development causes malformations, whereas deficiency later in brain development causes microscopic abnormalities and impairs subsequent function. A limited number of studies suggest that similar phenomena can occur in humans.


Assuntos
Encéfalo , Zinco/história , Animais , Encéfalo/anormalidades , Encéfalo/crescimento & desenvolvimento , Encéfalo/fisiologia , Cognição/efeitos dos fármacos , Feminino , História do Século XX , Humanos , Masculino , Zinco/deficiência , Zinco/fisiologia
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