Impact of micronutrients supplementation on bone repair around implants: microCT and counter-torque analysis in rats

ABSTRACT The use of natural substances and micronutritional approaches has been suggested as a therapeutic alternative to benefit the bone healing associated with no side effects. Nevertheless, the influence of micronutritional interventions with therapeutic proprieties on the bone repair has yet to be intensely evaluated, and no evidence is available exploring the impact of micronutrient supplementation on the peri-implant bone healing. Objective This study investigated the effect of micronutrients supplementation on the bone repair around implants. Material and Methods One screw-shaped titanium implant was inserted in each tibia of each rat, which were assigned to: daily administration, for 30 d, of the placebo solution (Placebo group-n:18) or micronutrients supplementation (Micronutrients group-n:18), based on calcium, magnesium, zinc, and vitamin D3 intake. After, the animals were sacrificed. One of the implants was removed by applying a counter-torque force to evaluate the force to rupture the bone-implant interface. The other implant was evaluated by microcomputed tomography (CT) examination to determine the bone-to-implant contact (BIC) and the bone volume (BV/TV). Results No statistically significant differences were observed between the groups for both counter-torque values and microCT parameters (p>0.05). Conclusion Within the limits of this study, micronutrients supplementation did not provide additional benefits to the bone healing around dental implants.

Efecto de nutrientes sobre la producción de biomasa del hongo medicinal Ganoderma lucidum / Effect of nutrients in the biomass production of the medicinal mushroom Ganoderma lucidum

El hongo Ganoderma lucidum, en los constituyentes de su biomasa, tiene compuestos con propiedades benéficas para la salud; es por esto que el conocimiento de las condiciones nutricionales adecuadas para su crecimiento permitirá su producción industrial y a bajo costo. En este trabajo se evaluó a nivel de matraz el efecto de la relación C/N, y la presencia de diferentes fuentes de carbono, nitrógeno y micronutrientes sobre la producción de biomasa. Empleando glucosa y peptona como fuentes de carbono y nitrógeno, respectivamente, se encontró una relación C/N óptima de 16,7:1 para la cual la máxima producción de biomasa fue de 25 g/L. Manteniendo esta relación C/N, y sustituyendo la glucosa por lactosa o harina de cebada y la peptona por extracto de levadura, la producción de biomasa se incrementó a 35 g/L. En presencia de harina de cebada la adición al medio de cultivo de sales de Mg y K, y de tiamina, no generó un mayor incremento en la producción de biomasa. La producción de biomasa de G. lucidum se ve favorecida por la presencia en el medio de cultivo de relaciones C/N cercanas a las reportadas conforme a la composición típica de los hongos, así como por la presencia de sustratos complejos como la harina de cebada que le aportan además de la fuente de carbono micronutrientes necesarios para su desarrollo.

Ganoderma lucidum fungus has some biomass components with beneficial health properties. The knowledge about its nutritionals requirements for growing will favor its industrial production at lower cost. In this work, the effect of C/N ratio, the presence of different carbon, nitrogen and micronutrients sources, on fungal biomass production, were evaluated. Using glucose and peptone as carbon and nitrogen sources, respectively, an optimal C/N ratio of 16,7:1 was found, for which the maximal biomass production was 25 g/L. Replacing glucose by lactose or barley flour and peptone by yeast extract at the same C/N ratio, the biomass production was enhanced to 35 g/L. With barley flour in the culture medium, the presence of Mg and K salts and thiamine did not turn out into a major increase of biomass. The G. lucidum biomass production is promoted by C/N ratios in the culture medium nearly equivalent to that found in the fungus, as well as the presence of complex substrates as barley flour which, additionally, contributes with important micronutrients along with the carbon source.

Zinc en la infancia: rompiendo paradigmas / Zinc in childhood: breaking paradigms

El zinc es un ejemplo de un micronutriente esencial, cuya deficiencia juega un papelimportante en la comprensión de las altas tasas de mortalidad y morbilidad infantil en países en desarrollo. Tanto la deficiencia intermedia de zinc como de vitamina A, pueden pasar inadvertidas clínicamente. Con respecto a la inmunidad, el zinc es fundamental para las funciones de tejidos de alto recambio, especialmente en el sistema inmunitario, y su deficiencia se asocia a alteraciones de la inmunidad innata, la inmunidad humoral y la inmunidad celular. Existe evidencia que avala la s u p l eme n t a c i o n d e z i n c d u r a n t e e inmediatamente después de un episodio de diarrea aguda, con lo que se disminuye su tiempo de duración y la gravedad, con reducción en la incidencia de diarrea en los dos o tres meses siguientes.Aun no se conoce exactamente cuál es el mecanismo que explique por qué se encuentra limitada la proliferación celular ante la deficiencia de zinc.

Zinc is an example of an essential micronutrient whose deficiency plays an important role in understanding the high rates of infant mortality and morbidity in developing countries. Both intermediate zinc deficiency and vitamin A, may go unnoticed clinically.With respect to immunity, zinc is essential for the functions of tissues of high turnover, especially in the immune system, and its deficiency is associated with alterations of innate immunity, humoral immunity and cellular immunity. There is evidence supporting zinc supplementation during and immediately after an episode of acute diarrhea, which shortens their duration and severity, with a reduction in the incidence of diarrhea in the two or three months. Still not known exactly what the mechanism that explains why it is limited to cell proliferation in zinc deficiency.

Nutrition and development: other micronutrients' effect on growth and cognition.

Previous studies have provided strong evidence that protein-energy malnutrition, deficiencies of iron and iodine early on in life led to compromised growth and cognitive functions in young children. Recently, a growing body of knowledge indicated that other micronutrients also play a role in young child development. Severe as well as marginal vitamin A efficiency were shown to lead to an increased risk of morbidity and mortality in children. A meta-analysis of vitamin A intervention trials indicated an overall reduction of 23% in all-cause mortality rate. Delayed growth, especially stunting, was reported in children with clinical signs of vitamin A deficiency. In addition, deficiency of zinc, which is essential for DNA and protein synthesis, leads to growth failure and delayed secondary sexual maturation in man and animals. Preterm infants appear to benefit from zinc administration in terms of growth and development. Supplementation studies in infants and older children revealed that those who manifested overt zinc deficiency through either clinical or biochemical indicators showed an improvement in linear growth and occasionally, an increase in weight gain. Zinc may also play a major role in brain function based on strong evidence from experimental animals. Zinc deficiency gestation in mice, rats, rhesus monkeys caused impaired learning, reduced attention and poor memory in their offspring. Data in humans are few and inconclusive. With respect to brain function alone, other nutrients such as docosahexaenoic acid (DHA, 22:6 n-3 fatty acid) improve visual acuity and mental development in small-for-gestational-age infants, folate supplementation during pregnancy prevents neural tube defect in infants, selenium deficiency in animals affects activities of brain enzymes necessary for brain development and function. Although evidence is accumulating that micronutrients other than iron and iodine may be important for physical growth and brain development in young children, more well-controlled studies in humans are needed. Critical issues to be considered include: single vs multiple limiting nutrients, critical period of deficiency, responsive indicators and variables that may affect the results as environmental, psychological and social factors.