El cabello, fuente de información del estado de salud / The hair, source of health information

El cabello y especialmente el localizado en la cabeza provee importante información sobre posibles exposiciones ambientales y/o laborales a diferentes elementos. El pelo puede ser considerado como un producto excretor, y su estudio reflejaría el metabolismo de minerales en el cuerpo. Nuestro propósito en el presente estudio es conocer si datos existentes dan información poblacional sobre la presencia de elementos tóxicos o no a través del análisis del cabello humano. RESULTADOS: Fue analizada la información proveniente de 241 muestras de cabello, de los cuales 163 (67,6%) corresponden al sexo femenino y 78 (32,4%) al masculino. Fueron analizados 22 elementos esenciales y 17 elementos de tóxicos. Entre los elementos esenciales presentaron resultados elevados Calcio (Ca), Magnesio (Mg), Manganeso (Mn), Molibdeno (Mo), Vanadio (V), Estroncio (Sr) y Circonio (Zr); entre los elementos tóxicos tuvieron valores elevados Aluminio (Al), Arsénico (As), Bario (Ba), Bismuto (Bi), Cadmio (Cd), Níquel (Ni), Plomo (Pb), Mercurio (Mg), Plata (Ag), Estaño (Sn). CONCLUSIÓN. Nuestro estudio muestra a nivel poblacional, no individual, puntos de alerta por la carencia o exceso de algunos elementos analizados debiéndose continuar con estudios locales interdisciplinarios en los cuales exista información sobre enfermedades, hábitos alimentarios, hábitos tóxicos, actividad laboral y exposición ambiental a los diferentes elementos. (AU)

Hair, especially localized in the head, provides important information on possible environmental and/or labor exposures to different elements. Hair can be considered as an excretory product, and its study would reflect the metabolism of minerals in the body. Our purpose in this study was to determine whether existing population data provide information on the presence of toxic and non-toxic elements by analizing human hair. RESULTS: We analyzed information from 241 hair samples, of which 163 (67.6%) are from females and 78 (32.4%) are from males. There were analyzed 22 essential elements and 17 toxic elements. Among the essential elements that had elevated results there were: Calcium (CA), magnesium (Mg), manganese (Mn), molybdenum (Mo), vanadium (V), strontium (Sr) and zirconium (Zr); among the toxic elements, those with higher values were: Aluminum (Al), arsenic (As), barium (BA), bismuth (Bi), Cadmium (Cd), Nickel (Ni), lead (Pb), Mercury (Mg), silver (Ag), tin (Sn). CONCLUSION. Our study shows at population level, not individual, warning points due to the lack or excess of some elements analyzed. It is reccommended to continue the research with local interdisciplinary studies which include information on diseases, eating habits, toxic habits, work activity and environmental exposure to different elements. (AU)

Synthesis, characterization and biological activity of chelated minerals

Cobalt, Copper and Zinc complexes of amino acids [lysine and glycine] were prepared and characterized by IR, electronic absorption spectra, elemental analysis, magnetic susceptibilities, the differential thermal analysis [DTA] and thermal gravimetric analysis [TGA] of the complexes pointed to their stability. The thermodynamic parameters of the dissociation steps are evaluated. The metal chelates and ligands have been screened for their invitro antibacterial against. Bacillus cereus, Salmonella yeast, E-coli and Staphylococcus. The metal complex [copper glycine] was shown to posses more antibacterial activity than the unchelated ligands. The adsorption ability of complexes to aflatoxin has been studied

Mineralogical composition of khamasin wind dust at Assiut, Eygpt

The present study investigated the mineralogical composition of the deposited dust from Khamasin wind on the agricultural soils at Assiut city through April 2008 and 2009. Five sites were chosen between the fringes of eastern and western deserts throughout the Nile valley. Wood boxes [dimensions of 1xlm] were put in the selected sites and precipitated dust was collected from each box after the finish of Khamasin storms in the two years. The quantity, pH and EC were determined for the collected Khamasin dust. The mineral particles of these dusts were examined by the scanning electron microscope [SEM] and the X-ray analysis. The obtained results revealed some variation in the dust quantity of Khamasin wind in the year of 2008 and 2009. The quantity of the collected bulk samples of the Khamasin dust varied from site to another in both 2008 and 2009 years. The highest amounts in both years are recorded in the sites of the eastern side of the Nile valley that faraway from the western desert where the Khamasin wind come. The mean values of dust EC and pH were low and similar in both years of 2008 and 2009. The Scanning electron microscope photomicrographs showed that the grain sizes of Khamasin dust in the sites located in the interference zone of Nile valley with the eastern desert were finer than those in site located in the western side of the Nile river. Generally, relatively large angular to subangular grains, larger amount of very Fine grains with more oblate particle and spherical particles with differences in size as well as particles with irregular shapes in Khamasin dust of 2008 and 2009 years. Semi-quantitative measurements of the identified minerals in the Khamasin dust of 2008 year have shown the order of quartz >k-feldspar>calcite> magnetite >epidote> anhydrite > garnet > augite> tourmaline > zircon > ilmenite > plagioclase > goethite > actinolite > hematite. However, the minerals in the Khamasin dust of 2009 year could be ordered as quartz >k-feldspar>calcite>epidote> magnetite > tourmaline > anhydrite > augite > plagioclase >Imenite>rutile> hematite > garnet >actinolite. There was no general trend for distribution of these minerals throughout the studied sites. From a qualitative point of view, most of the sites have the same mineralogical composition. Comparison of the mineralogical compositions of mineral dusts at the five sites, revealed certain quantitative differences

Water sorption and solubility of different calcium hydroxide cements

OBJECTIVES: Calcium hydroxide cements have been largely used in deep cavities due to their abilities to stimulate dentin formation. However, their resistance can be relatively low and their solubility relatively high, in many instances. This study evaluated water sorption and solubility of different calcium hydroxide cements, in order to show alterations that may reduce their effectiveness. MATERIAL AND METHODS: Five discs (20 mm in diameter and 1.5 mm thick) of three different materials (Biocal®, Dycal® and Hidro C®) were prepared with the aid of a ring-shaped metallic matrix. After being stored at 37ºC for 24 h, the discs were weighed on a precision weight scale, dehydrated and weighed again. Immediately after weighing, discs were stored for a week in 50 mL of distilled water at 37ºC and, then, weighed again, dehydrated and submitted to a new weighing. The loss of soluble material and its water sorption was obtained from the difference between the initial and the final dry mass of each disc, after 1 week of immersion in water. Data were analyzed for significant differences by two-way ANOVA and Tukey's test (p<0.05). RESULTS: Mean water sorption values (g) ± standard deviation and percentage ( percent), for each evaluated cement, were: Biocal® (0.006 ± 0.001 / 2.15); Dycal® (0.016 ± 0.004 / 5.49); and Hidro C® (0.025 ± 0.003 / 8.27). Mean solubility values (g) ± standard deviation and percentage ( percent), for each evaluated cement, were: Biocal® (0.002 ± 0.001 / 0.72); Dycal® (0.013 ± 0.004 / 4.21); and Hidro C® (0.023 ± 0.004 / 7.65). CONCLUSIONS: Biocal® absorbed less water and was less soluble than the other evaluated cements; Hidro C® exhibited the highest water sorption and solubility values; and there were significant differences among all evaluated experimental groups.

Physicochemical characterization of two deproteinized bovine xenografts

Calcium phosphate salts, or more specifically hydroxyapatite, are products of great interest in the fields of medical and dental science due to their biocompatibility and osteoconduction property. Deproteinized xenografts are primarily constituted of natural apatites, sintered or not. Variations in the industrial process may affect physicochemical properties and, therefore, the biological outcome. The purpose of this work was to characterize the physical and chemical properties of deproteinized xenogenic biomaterials, Bio-Oss (Geistlich Biomaterials, Wolhuser, Switzerland) and Gen-Ox (Baumer S.A., Brazil), widely used as bone grafts. Scanning electron microscopy, infrared region spectroscopy, X-ray diffraction, thermogravimetry and degradation analysis were conducted. The results show that both materials presented porous granules, composed of crystalline hydroxyapatite without apparent presence of other phases. Bio-Oss presented greater dissolution in Tris-HCl than Gen-Ox in the degradation test, possibly due to the low crystallinity and the presence of organic residues. In conclusion, both commercial materials are hydroxyapatite compounds, Bio-Oss being less crystalline than Gen-Ox and, therefore, more prone to degradation.

[On the] geochemistry and mineral chemistry of the Gabbroic rocks at Wadi Um Khors area, central eastern desert, Egypt

The studied metagabbro-diorite complex comprises hornblende metagabbro, quartz-metagabbro, appinitic-metagabbro, and quartz diorite beside the fresh gabbro relics. They are calc-alkaline and were emplaced at subduction zones related to island arc magma. They were subjected to metamorphism but still carry minor relics of fresh gabbro. Mineralogically, the metagabbroic rocks are composed of plagioclase [An 30-45], Ca-rich clinopyroxenes [diopside and augite] and hornblende of green and olive brown colour]. The obtained crystallization temperature for the coexisting plagioclase- olive brown hornblende mineral pair was 600 - 700 °C and for the coexisting plagioclase- green hornblende mineral pair was 800 - 900 °C. The Ca-rich clinopyroxenes are low in alumina content suggesting crystallization between 500 and 1100 °C at shallow depth. Also, the analyzed clinopyroxenes pertain to those found in sub- alkaline rocks. The studied metagabbroic rocks show relative enrichments in LILE [Sr, Rb, Ba] over the HFSE [Nb, Zr, Y], a feature characteristic of subduction- related magmas

Influence of calcium and non-phytate phosphorus deficient diets with phytase on the performance of broilers, serum concentrations of minerals and the activity of alanin transaminase, aspartate transaminase and lactate dehydrogenase

An experiment was conducted to study the effect of microbial phytase [phyzyme XP5000G] supplementation in broiler chicks' diets on the performance, serum total protein [TP], minerals [Ca, Mg and P] and the serum enzyme activities [AST, ALT, LDH]. A reference -1 -1 diet adequate in calcium and non-phytate phosphorus [10.0 gkg Ca and 5 gkg nPP] and two -1 -1 -1 -1 deficient diets in Ca and nPP [8.5 gkg Ca and 3.5 gkg nPP, and 7.5 gkg Ca and 2.5 gkg nPP] -1 with or without phytase [0 and 100mgkg] were offered to broiler chicks from 1 to 21 days of age. Although the low-nPP diets had no significant effect on body weight gain [BWG] of chicks [p > 0.05] They increased [p < 0.01] feed intake [FI] and feed conversion ratio [FCR] when compared to the low-nPP diet supplemented with enzyme. Phytase had a favorable effect, although non-significantly, on BWG of chicks fed very low level of nPP. Enzyme reduced the feed intake [p < 0.05] and improved the FCR of Ca-nPP deficient chicks [p < 0.01]. The decrease in Ca-nPP content in the diet caused a significant increase in serum concentration of Ca [p < 0.05] and decrease in P concentration [p < 0.05]. Low Ca-nPP diets had no influence on serum Mg concentration. Dietary phytase reduced the Ca level and increased the P level [p < 0.05] of serum in chicks fed with Ca-nPP deficient diets. The activity of LDH increased [p < 0.01] in response to low dietary Ca and nPP, deficient but there was no influence on serum ALT and AST activity and TP content [p > 0.05]. Phytase supplementation reduced serum ALT [p < 0.05] and had no effect on AST [p > 0.05]. Serum LDH activity further increased [p < 0.01] by phytase supplementation. These results demonstrated that the performance of the chicks received low

Morphological and chemical analysis of bone substitutes by scanning electron microscopy and microanalysis by spectroscopy of dispersion energy

This study evaluated the morphological and chemical composition of the following bone substitutes: cancellous and cortical organic bovine bone with macro and microparticle size ranging from 1.0 to 2.0 mm and 0.25 to 1.0 mm, respectively; inorganic bovine bone with particle size ranging from 0.25 to 1.0 mm; hydroxyapatite with particle size ranging from 0.75 to 1.0 mm; and demineralized freeze-dried bone allograft with particle size ranging from 0.25 to 0.5 mm. The samples were sputter-coated with gold in an ion coater, the morphology was observed and particle size was measured under vacuum by scanning electron microscopy (SEM). The chemical composition was evaluated by spectroscopy of dispersion energy (EDS) microanalysis using samples without coating. SEM analysis provided visual evidence that all examined materials have irregular shape and particle sizes larger than those informed by the manufacturer. EDS microanalysis detected the presence of sodium, calcium and phosphorus that are usual elements of the bone tissue. However, mineral elements were detected in all analyzed particles of organic bovine bone except for macro cancellous organic bovine bone. These results suggest that the examined organic bovine bone cannot be considered as a pure organic material.

Neste estudo foram avaliados a morfologia, o tamanho e a composição química dos seguintes substitutos ósseos: osso bovino orgânico cortical e esponjoso com micropartículas medindo entre 0,25 e 1,0 mm e macropartículas medindo entre 1,0 e 2,0 mm; osso bovino cortical inorgânico com partículas medindo entre 0,25 e 1,0 mm; hidroxiapatita com partículas medindo entre 0,75 e 1,0 mm; e osso humano descalcificado, congelado e seco medindo entre 0,25 a 0,5 mm. Para a analise da morfologia e tamanho das partículas, as amostras foram preparadas em porta-espécime, metalizadas em ouro e analisadas a vácuo em microscopia eletrônico de varredura (MEV). Para a análise da composição química, as partículas não foram metalizadas e foram analisadas por microanálise por espectroscopia por dispersão de energia (EDS). A análise em MEV, demonstrou que as partículas substitutos ossos apresentaram formato irregular e tamanho variável, maior do que o mencionado pelo fabricante. A microanálise por EDS detectou a presença de elementos como sódio, cálcio e fósforo, que são comuns à composição do tecido ósseo, porém revelaram a presença de elementos químicos nas partículas de osso bovino orgânico, exceto para a macropartícula de osso bovino orgânico esponjoso. Esses resultados sugerem que o osso bovino orgânico não pode ser considerado um material orgânico puro.

From geochemistry and biochemistry to prebiotic evolution... we necessarily enter into Gánti's fluid automata

The present study is just an overview of the opening of the geochemical stage for the appearance of life. But that opening would not have been sufficient for the intellectual discovery of the origin of life! The excellent works and many commendable efforts that advance this explanation have not shown the fundamental elements that participate in the theoretical frame of biological evolution. The latter imply the existence of evolutionary transitions and the production of new levels of organization. In this brief analysis we do not intend to introduce the audience to the philosophy of biology. But we do expect to provide a modest overview, in which the geochemical chemolithoautotrophic opening of the stage should be seen, at most, as the initial metabolism that enabled organic compounds to follow the road where a chemical fluid machinery was thus able to undertake the more [quot ]sublime[quot ] course of organic biological evolution. We think that Tibor Gánti's chemoton is the most significant contribution to theoretical biology, and the only course now available to comprehend the unit of evolution problem without the structuralist and functionalist conflict prevalent in theoretical biology. In our opinion Gánti's chemoton theory travels to the [quot ]locus[quot ] where evolutionary theory dares to extend itself to entities at many levels of structural organization, beyond the gene or the group above. Therefore, in this and subsequent papers on the prebiotic conditions for the eventual appearance of the genetic code, we explore the formation and the presence of metal sulfide minerals, from the assembly of metal sulfide clusters through the precipitation of nanocrystals and the further reactions resulting in bulk metal sulfide phases. We endeavor to characterize pristine reactions and the modern surfaces, utilizing traditional surface science techniques and computational methods. Moreover, mechanistic details of the overall...

Interactive effects of water stress and gibberellic ai cd on mineral composition of fenugreek plant

12 days-old fenugreek plants were grown in stressed nutrient solutions imposed by NaCl or PEG 4000 to obtain isosmotic solutions of osmotic potentials ranging from 0 to -8 bars. The different stress levels were applied from the onset of germination in treatment I, while in treatment II, the stress levels were applied after 5 days of germination at zero stress level. The interactive effects between GA3, as a presoaking medium, and water stress was also studied. At the lowest osmotic potential, the shoots of salt-stressed plants from both treatments had higher sodium and chloride contents and lower potassium, calcium, magnesium and total phosphorus levels. Such ionic composition was altered in PEG-stressed plants, where the contents of sodium, magnesium and chloride were greatly reduced and balanced by an increase in the level of potassium, calcium and total phosphorus compared with those under saline condition. A similar pattern of ionic changes was demonstrated in GA3-presoaked plants when the external osmotic potential level decreased Na+, K+, Ca2+, Cl- and insoluble phosphorus fraction, it decreases the Mg2+ level under control and each stress condition