Electrochemical Cathodic Polarization, a Simplified Method That Can Modified and Increase the Biological Activity of Titanium Surfaces: A Systematic Review.

BACKGROUND: The cathodic polarization seems to be an electrochemical method capable of modifying and coat biomolecules on titanium surfaces, improving the surface activity and promoting better biological responses. OBJECTIVE: The aim of the systematic review is to assess the scientific literature to evaluate the cellular response produced by treatment of titanium surfaces by applying the cathodic polarization technique. DATA, SOURCES, AND SELECTION: The literature search was performed in several databases including PubMed, Web of Science, Scopus, Science Direct, Scielo and EBSCO Host, until June 2016, with no limits used. Eligibility criteria were used and quality assessment was performed following slightly modified ARRIVE and SYRCLE guidelines for cellular studies and animal research. RESULTS: Thirteen studies accomplished the inclusion criteria and were considered in the review. The quality of reporting studies in animal models was low and for the in vitro studies it was high. The in vitro and in vivo results reported that the use of cathodic polarization promoted hydride surfaces, effective deposition, and adhesion of the coated biomolecules. In the experimental groups that used the electrochemical method, cellular viability, proliferation, adhesion, differentiation, or bone growth were better or comparable with the control groups. CONCLUSIONS: The use of the cathodic polarization method to modify titanium surfaces seems to be an interesting method that could produce active layers and consequently enhance cellular response, in vitro and in vivo animal model studies.

Determination of fexofenadine in Hank's balanced salt solution by high-performance liquid chromatography with ultraviolet detection: application to Caco-2 cell permeability studies.

The drug-transporting proteins can affect the pharmacokinetics and pharmacodymanics of many drugs, resulting in an erratic and unpredictable pharmacological response. The Caco-2 monolayer is routinely applied to investigate the carrier-mediated transport of drugs. Therefore, the selection of a marker compound able to characterize the activity of such transporters is crucial. Fexofenadine (FEX), a P-gp/OATP substrate, can be considered a suitable probe. However, in order to use be used as a marker compound, it is mandatory to develop an analytical method able to quantify this drug during the in vitro permeability assay. An HPLC method with ultraviolet detection was developed; the mobile phase consisted of phosphate buffer (pH 3.2) containing 10 m m of sodium octanosulphonate and acetonitrile (60:40) and the flow rate was set at 1.2 mL/min. Fexofenadine was eluted at 40°C, the retention time was about 4.6 min. The LOD and LOQ values were 1.9 and 6.2 ng/mL, respectively. Verapamil and ketoconazole, the most common P-gp inhibitors, were eluted as distinct peaks of that corresponding to fexofenadine The method was successfully applied to quantify the amount of FEX transported across the Caco-2 monolayer and could be an additional tool for those investigating the role of membrane transporters on drug absorption.

Evaluation of antioxidant, immunomodulatory, and cytotoxic action of fractions from Eugenia uniflora L. and Eugenia malaccensis L.: correlation with polyphenol and flavanoid content.

An increasing number of biological activities presented by medicinal plants has been investigated over the years, and they are used in the search for new substances with lower side effects. Eugenia uniflora L. and Eugenia malaccensis L. (Myrtaceae) have many folk uses in various countries. This current study was designed to quantify the polyphenols and flavonoids contents and evaluate the immunomodulatory, antioxidant, and cytotoxic potentials of fractions from E. uniflora L. and E. malaccensis L. It was observed that the polyphenol content was higher in ethyl acetate fractions. These fractions have high antioxidant potential. E. malaccensis L. seeds showed the largest DPPH radical scavenger capacity (EC50 = 22.62). The fractions of E. malaccensis L. leaves showed lower antioxidant capacity. The samples did not alter the profile of proinflammatory cytokines and nitric oxide release. The results indicate that species of the family Myrtaceae are rich in compounds with antioxidant capacity, which can help reduce the inflammatory response.

Cellular antioxidant activity of feijoada whole meal coupled with an in vitro digestion.

Consumption of plant food rich meals, such as feijoada, a traditional meal in Brazil, is associated with the reduction of chronic disease. The objectives of this study were to determine phytochemical content and antioxidant activity by chemical and cellular antioxidant assays (CAA) of feijoada with or without in vitro digestion. Feijoada showed no difference in phenolics and flavonoids after digestion. Bound and residue contributions to total phenolics were 20.9% and 32.2%, respectively, suggesting that phenolics reach the colon after intake. Flavonoids in residue and bound fractions represented 50% of total flavonoids. Antioxidant activity of feijoada without digestion was higher than that with digestion; however, it showed lower antiproliferative activity and CAA. Feijoada with in vitro digestion also yielded phenolics with higher CAA. Analyses of whole meals should be used to evaluate phytochemicals present in food mixtures consumed, especially with digestion models coupled with CAA resulting in information similar to those in physiological conditions.

The effect of temperature on growth and production of paralytic shellfish poisoning toxins by the cyanobacterium Cylindrospermopsis raciborskii C10.

Cylindrospermopsis raciborskii is a cyanobacterium which produces either cylindrospermopsine or paralytic shellfish poisoning (PSP) toxins. We studied the effect of temperature on growth and production of PSP toxins by C. raciborskii C10, isolated from a freshwater reservoir in Brazil. We analyzed the extracellular and intracellular content of PSP toxins at two different temperatures: 19 and 25 degrees C. C. raciborskii C10 produces STX, GTX2, and GTX3 at both temperatures. dcSTX was also detected at 25 degrees C in the intracellular extracts obtained at the end of the stationary phase. The growth achieved at 25 degrees C and estimated by optical density at 700 nm was three times greater than at 19 degrees C. However, no significant differences were observed in the content of PSP toxins in either the cells or the extracellular media. The kinetics of accumulation of PSP toxins within the cells rather than in the media suggests an active PSP toxins-export process that is not related to cell lysis. The extracellular accumulation of PSP toxins at 19 degrees C suggested a biotransformation of STX to the epimers GTX2 and GTX3. The stability of the PSP toxins produced by C. raciborskii C10 was high enough for them to remain active in the media after 30 days (at 25 degrees C) or after 50 days (at 19 degrees C).

Iron and its sensitive balance in the cell.

Iron is vital in life because it is an important component of molecules that undergoes redox reactions or transport oxygen. However, the existence of two stable and inter-convertible forms of iron, iron(III) and iron(II), makes possible one electron being transferred to or captured from other species to form radicals. In particular, superoxide and hydroxyl radicals may be formed in these reactions, both with capacity of attacking other molecules. DNA is one important target and a vast literature exists showing that attack of hydroxyl radical to DNA leads to cell death cellular necrosis, apoptosis, mutation and malignant transformation. Therefore, a fine balance must exist at various levels of an organism to maintain iron concentration in a narrow range, above and below which deleterious effects of distinct nature occur. This review will deal with the formation of oxygen reactive species in iron participating reactions, defenses in the organism against these species, the different mechanisms of iron homeostasis and iron deficiency and iron overload related diseases.

Secretion from neuropeptide-treated splenocytes modifies ovarian steroidogenesis

There are evidences for modulation of immune function by the sympathetic nervous system and its principal neurotransmitter norepinephrine (NE) throgugh superior ovarian nerve (SON)-coeliac ganglionnoradrenergic postganglionic innervation of the spleen. Seven days after SON transection at 53 days of age, the rat splenocytes were isolated and then cultured for 48h. These culture media, used to simulate ovaries from 60-day- old intact rats (neither SON-transected nor sham-operated) at diestrus 2 stage, in in vitro incubations, showed adecrease in progesterone release, an increase in estradiol release and no change in androstenedione release in relation to splenocyte culture media from control (sham-operated) rats.When esplenocytes from SON transected (SON-t) rats were treated with vasoactive intestinal peptide (VIP) or neuropeptide Y (NPY), both at 16-6M for 24h, their secretions increased the progesterone release while decreasing the estradiol release from the intact ovaries, compared with the secretions of untreated splenocytes from SON-t rats. Although the secretions of splenocytes treated with VIP decrease the androstenedione release from de ovaries, the treatment with NPY produced no change in hormone release. In the present paper the ovarian steroidogenic response, which was modified by the effects of an in vivo SON transection on spleen cells, was reverted by an in vitro system in which the splenocytes were treated with VIP or NPY. This could indicate that the spleen of SON-t rats does not receive those neuropeptides by neural route however, when they are added to splenocyte culture in vitro, the cell secretions revert the profile of steroid hormones released from the intact ovary. We also present functional evidence for modulation of the immune function by sympathetic nervous system and neurotransmitters other than NE. (AU)

Secretion from neuropeptide-treated splenocytes modifies ovarian steroidogenesis

There are evidences for modulation of immune function by the sympathetic nervous system and its principal neurotransmitter norepinephrine (NE) throgugh superior ovarian nerve (SON)-coeliac ganglionnoradrenergic postganglionic innervation of the spleen. Seven days after SON transection at 53 days of age, the rat splenocytes were isolated and then cultured for 48h. These culture media, used to simulate ovaries from 60-day- old intact rats (neither SON-transected nor sham-operated) at diestrus 2 stage, in in vitro incubations, showed adecrease in progesterone release, an increase in estradiol release and no change in androstenedione release in relation to splenocyte culture media from control (sham-operated) rats.When esplenocytes from SON transected (SON-t) rats were treated with vasoactive intestinal peptide (VIP) or neuropeptide Y (NPY), both at 16-6M for 24h, their secretions increased the progesterone release while decreasing the estradiol release from the intact ovaries, compared with the secretions of untreated splenocytes from SON-t rats. Although the secretions of splenocytes treated with VIP decrease the androstenedione release from de ovaries, the treatment with NPY produced no change in hormone release. In the present paper the ovarian steroidogenic response, which was modified by the effects of an in vivo SON transection on spleen cells, was reverted by an in vitro system in which the splenocytes were treated with VIP or NPY. This could indicate that the spleen of SON-t rats does not receive those neuropeptides by neural route however, when they are added to splenocyte culture in vitro, the cell secretions revert the profile of steroid hormones released from the intact ovary. We also present functional evidence for modulation of the immune function by sympathetic nervous system and neurotransmitters other than NE.

Sensibilidad celular al colágeno vascular en pacientes con trombogene trombo-angeítis obliterante (enfermedad de Leo Buerger) / Celular sensibility to vascular collagen in patients with thrombogen thromboangiitis obliterant (Leo Buerger's disease)

La Tromboangeitis Obliterante (TAO) es una panarteritis segmentaria en vasos de mediano y pequeño calibre que afecta fundamentalmente varones, fumadores, menores de 40 años. Su etiología es desconocida, pero se cree que participan mecanismos de autoinmunidad. Se estudiaron 7 pacientes (6 varones y 1 hembra) con TAO de menos de 1 año de evolución. 3 con vasculitis y 10 controles sanos. Se exploró la proliferación de las células mononucleares en presencia de fitohemaglutinina (PHA) y colágeno tipo I y III. Los resultados sugieren: a) Proliferación normal en presencia de PHA tanto en los pacientes con TAO como en aquellos con vasculitis; b) Sólo 2 pacientes con TAO y ninguno con vasculitis mostraron sensibilidad celular al colágeno. Podemos concluir, que la sensibilidad celular al colágeno pudo ponerse de manifiesto en TAO de corto tiempo de evolución