Frank Hernández
University of Havana
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Featured researches published by Frank Hernández.
Free Radical Biology and Medicine | 1995
Frank Hernández; Silvia Menéndez; Rolando Wong
Patients with cardiac infarction show a decrease in glutathione peroxidase and superoxide dismutase activities, which are beginners in the scavenger processes of lipid peroxide and superoxide radicals, respectively. In this study, we investigate the effects of endovenous ozone therapy on serum lipid pattern and on antioxidant defense system, such as te glutathione redox one, in the blood of patients with myocardial infarct. Twenty-two patients who had an infarction, between 3 months and 1 year before the study, were treated with ozone by autohemotherapy during 15 sessions. A statistically significant decrease in plasma total cholesterol and low density lipoprotein was observed. High biologically significant increases on erythrocyte glutathione peroxidase and glucose 6-phosphate dehydrogenase activities were found. There was no change in plasma lipid peroxidation level. It was concluded that endovenous ozone therapy in patients with myocardial infarction has a beneficial effect on blood lipid metabolism, provoking the activation of antioxidant protection system.
Mediators of Inflammation | 2005
Zullyt Zamora; Aluet Borrego; Orlay Y. López; René Delgado; Ricardo González; Silvia Menéndez; Frank Hernández; Siegfried Schulz
Ozone oxidative preconditioning is a prophylactic approach, which favors the antioxidant-prooxidant balance for preservation of cell redox state by the increase of antioxidant endogenous systems in both in vivo and in vitro experimental models. Our aim is to analyze the effect of ozone oxidative preconditioning on serum TNF-α levels and as a modulator of oxidative stress on hepatic tissue in endotoxic shock model (mice treated with lipopolysaccharide (LPS)). Ozone/oxygen gaseous mixture which was administered intraperitoneally (0.2, 0.4, and 1.2 mg/kg) once daily for five days before LPS (0.1 mg/kg, intraperitoneal). TNF-α was measured by cytotoxicity on L-929 cells. Biochemical parameters such as thiobarbituric acid reactive substances (TBARS), enzymatic activity of catalase, glutathione peroxidase, and glutathione-S transferase were measured in hepatic tissue. One hour after LPS injection there was a significant increase in TNF-α levels in mouse serum. Ozone/oxygen gaseous mixture reduced serum TNF-α levels in a dose-dependent manner. Statistically significant decreases in TNF-α levels after LPS injection were observed in mice pretreated with ozone intraperitoneal applications at 0.2 (78%), 0.4 (98%), and 1.2 (99%). Also a significant increase in TBARS content was observed in the hepatic tissue of LPS-treated mice, whereas enzymatic activity of glutathion-S transferase and glutathione peroxidase was decreased. However in ozone-treated animals a significant decrease in TBARS content was appreciated as well as an increase in the activity of antioxidant enzymes. These results indicate that ozone oxidative preconditioning exerts inhibitory effects on TNF-α production and on the other hand it exerts influence on the antioxidant-prooxidant balance for preservation of cell redox state by the increase of endogenous antioxidant systems.
Mediators of Inflammation | 2004
Aluet Borrego; Zullyt Zamora; Ricardo González; Cheyla Romay; Silvia Menéndez; Frank Hernández; Teresita Montero; Enys Rojas
BACKGROUND: Acute renal failure is a dose-limiting factor of cisplatin chemotherapy. Here, we show the protective effect of ozone oxidative preconditioning against cisplatin-induced renal dysfunction in rats. Ozone oxidative preconditioning is a prophylactic approach, which favors the antioxidant-pro-oxidant balance for preservation of the cell redox state by increasing antioxidant endogenous systems in various in vivo and in vitro experimental models. AIMS: To analyze the protective role of ozone oxidative preconditioning against cisplatin-induced nephrotoxicity. METHODS: Male Sprague-Dawley rats were pretreated with 15 intrarectal applications of ozone/oxygen mixture at 0.36, 0.72, 1.1, 1.8 and 2.5 mg/kg before cisplatin intraperitoneal injection (6 mg/kg). Serum and kidneys were extracted and analyzed 5 days after cisplatin treatment for determinations of the renal content of glutathione, thiobarbituric acid-reactive substances, renal concentration and enzymatic activities of catalase, superoxide dismutase and glutathione peroxidase. RESULTS: Ozone pretreatment prevented the increase in serum creatinine levels, the glutathione depletion and the inhibition of superoxide dismutase, catalase and glutathione peroxidase activities induced by cisplatin in the rat kidney. Also, the renal content of thiobarbituric acid-reactive substances was decreased by ozone therapy. These protective effects of ozone were dose dependent. CONCLUSIONS: Intrarectal ozone therapy prevented effectively the renal antioxidant unbalance induced by cisplatin treatment.
Mediators of Inflammation | 2004
Ricardo González; Aluet Borrego; Zullyt Zamora; Cheyla Romay; Frank Hernández; Silvia Menéndez; Teresita Montero; Enis Rojas
BACKGROUND Ozone therapy has become a useful treatment for pathological processes, in which the damage mediated by reactive oxygen species is involved. Several lines of evidence suggest that cisplatin-induced acute nephrotoxicity is partially mediated by reactive oxygen species AIMS To analyze the effect of ozone administration after cisplatin-induced acute nephrotoxicity. METHODS Male Sprague-Dawley rats were treated with five intra-rectal applications of ozone/oxygen mixture at 0.36, 1.1 and 1.8 mg/kg after cisplatin intraperitoneal injection (6 mg/kg). Serum and kidneys were taken off 5 days after cisplatin treatment. Creatinine was measured in the serum and the activities of antioxidant enzymes and thiobarbituric acid reactive substances and glutathione content were analyzed in renal homogenate. RESULTS Ozone treatment diminished the increase in serum creatinine levels, the glutathione depletion and also reversed the inhibition of superoxide dismutase, catalase and glutathione peroxidase activities induced by cisplatin in the rat kidney. Also, the renal content of thiobarbituric reactive substances was decreased by ozone/oxygen mixture applied after cisplatin. CONCLUSION Intrarectal applications of ozone reversed the renal pro-oxidant unbalance induced by cisplatin treatment by the way of stimulation to some constituents of antioxidant system in the kidney, and thereby it decreased the renal damage.
Ozone-science & Engineering | 2001
Maritza F. Díaz; Irene Lezcano; Jesús Molerio; Frank Hernández
Abstract Ozonation reactions are very important in fatty acid chemistry since their ozonation products are involved in vital biological processes. When an unsaturated acid reacts with ozone in presence of an organic solvent, Criegee ozonides are produced according to the Criegee mechanism. These ozonides are relatively stable compounds, thus, in the organism they have biological effects at distant sites from the site they are formed. The antimicrobial activity of ozonized sunflower oil (O1eozonR) has been previously well documented. We have suggested that ozonides are involved in the antimicrobial effect of O1eozonR/. In this study we try to demonstrate this hypothesis. Ozonides were obtained by total reaction of ozone gas with a sample of methyl oleate in an organic solvent (hexane). Proton Nuclear Magnetic Resonance (H NMR) technique was used for identification of ozonides in ozonation products, whereas biological evaluation was done by determining Minimum Inhibitory Concentration (MIC), Minimum Bactericidal Concentration (MBC) and Minimum Fungicidal Concentration (MFC) of ozonation products of different microorganism. The ozonide signal was identified in the O1eozonR and ozonized methyl oleate while in sunflower oil was not. Ozonation products from methyl oleate, in our reaction conditions, were spectroscopically found to be only ozonides. MICs for ozonides from ozonized methyl oleate were from 2.3 to 28 mg/mL, whereas MBC and MFC were 460 mg/mL comparable with those from O1eozonR. These results demonstrate that ozonides are one of the active species of O1eozonR.
Experimental Parasitology | 2009
Frank Hernández; Damian Hernández; Zullyt Zamora; Maritza F. Díaz; Odelsa Ancheta; Sandra Rodríguez; Dinorah Torres
The ozonized sunflower oil product (Oleozon) was investigated to explore its cytotoxic activity on Giardia duodenalis in vitro cultivated trophozites. Oleozon produced inactivation of Giardia trophozoites in a dose- and cell density-dependent manner. Thirty microliter of Oleozon with peroxide index value of 500 equivalent-mmol of activated oxygen per kilogram were used to achieve a 100% inhibition (<-4.00 log unit) of trophozoites from an initial inoculum of 15x10(4) cells. This potent effect was confirmed by transmission electron microscopy where morphological deterioration of superficial structures mainly in the ventral disc, and formation of a great number of micro vesicles in the cytoplasm were found. We concluded that a direct chemical-oxidation attack by the active substances from Oleozon is one of the causes of the parasitocidal effect of this product. We suggest that the dose and cell density-dependent effect must be taken into account when prescription of this product for giardiasis treatment in humans.
Ozone-science & Engineering | 2005
Maritza F. Díaz; José A. Gavín Sazatornil; Oscar Ledea; Frank Hernández
Ozonation reactions are very important in vegetable oil chemistry since their ozonation products are involved in antimicrobial effect in therapeutical uses for several microbiological etiology diseases. Information on the spectroscopic characterization of the products generated by ozonolysis of sunflower oil is limited. In the present study ozonized sunflower oil with 650 mmol-equiv/kg of peroxide index is chemically characterized. Ozonation of sunflower oil produced ozonides, aldehydes and hydroperoxides which were identified by 1H, 13C and two-dimensional 1H Nuclear Magnetic Resonance (NMR). The virgin sunflower oil and ozonized sunflower oil show very similar 1H NMR spectra except for the resonances at δ = 9.74 and δ = 9.63 ppm that correspond to both triplet from aldehydic protons, δ = 5.6 ppm (olefinic signal from hydroperoxides), and δ = 5.15 ppm (multiplet from ozonides methylic protons). Other resonance assignments are based on the connectivities provided by the proton scalar coupling constants. These are the following: δ = 3.15 ppm (doublet from methylenic group in α position respect to olefinic proton), δ = 2.45 ppm (multiplet from methylenic group allylic to ozonides methynic protons) and δ = 1.62 ppm (multiplet methylenic protons in β position respect to ozonides methynic protons). From the 13C NMR and 1H-13C two- dimensional spectrum of the ozonized sunflower oil, the presence of ozonides was confirmed by the signals δ = 103.43 and δ = 103.49 ppm, respectively. The others new signals found in δ = 42.5 and δ = 42.76 ppm confirm the presence of methylenic carbons from hydroperoxides and ozonides. These results indicate that NMR Spectroscopy can provide valuable information about the amount of reaction compounds of ozonized vegetable oil. From the chemical structural elucidation of ozonated sunflower oils, relevant biochemical and chemical information can be achieved.
Mediators of Inflammation | 2005
Ricardo González; Cheyla Romay; Aluet Borrego; Frank Hernández; Nelson Merino; Zullyt Zamora; Enis Rojas
Cisplatin (CDDP), an anticancer drug, induces remarkable toxicity in the kidneys of animals and humans and it has been well documented that reactive oxygen species and the renal antioxidant system are strongly involved in acute renal damage induced by CDDP. The aim of the present study was to investigate whether or not the renal antioxidant system plays also an important role in chronic renal damage induced by repeated doses of CDDP (1 mg/kg intraperitoneally twice weekly during 10 weeks in rats). In order to elucidate it, serum creatinine and urea levels, renal glutathione and thiobarbituric acid-reactive substances (TBARS) content, as well as renal superoxide dismutase and glutathione peroxidase activities were measured in the kidney homogenates of chronically CDDP-treated rats and additionally histological studies were performed in the rat kidneys. The chronic treatment with CDDP induced a significant increase in creatinine and urea levels in serum, but the other parameters mentioned above were not significantly modified as compared to the values in nontreated rats. Taking into account these results, we conclude that chronic CDDP administration induces also severe nephrotoxicity, in contrast to CDDP acute application, without any significant modification in the activity of relevant antioxidant enzymes such as superoxide dismutase and glutathione peroxidase, renal glutathione and lipid peroxides, by which the role of the antioxidant system in chronic nephrotoxicity induced by CDDP in rats is uncertain.
Ozone-science & Engineering | 2006
Maritza F. Díaz; José A. Gavín; Magali Gómez; Vicente Curtielles; Frank Hernández
Prior studies have proven that ozonated vegetable oils present a high germicidal power. Ozonation of sunflower oil at different applied ozone dosage was carried out and peroxide and aldehydes indices along with antimicrobial activity were determined. The reaction products were identified using Proton Nuclear Magnetic Resonance Spectroscopy (1H NMR). The principal signals intensity values were used for following the reaction course between ozone and sunflower oil. The reaction was following up to peroxide index values of 1202 mmol-equi/kg. The intensities of olefinic proton signals decreased with the gradual increase in ozone concentration but without disappearing completely. The Criegee ozonides obtained at 107.1 mg/g of ozone doses were approximately 3.9-fold higher than that at beginning of the reaction. The aldehyde protons were observed as a weak intensity signal in all the spectra. The signals belonging to olefinic protons from hydroperoxides appeared weak and increased with the increase in ozone doses. Signals from other oxygenated groups were assigned. The highest action spectrum of antimicrobial activity was obtained with the higher peroxide index. It was concluded that at higher applied ozone doses, the higher the antimicrobial activity potential of ozonized sunflower oil
Ozone-science & Engineering | 2005
Maritza F. Díaz; Nayibi Núñez; Daraisy Quincose; Wilfredo Díaz; Frank Hernández
Abstract In the present study, the products from the ozonation of three systems (ozonized coconut oil, ozonized coconut oil with water and ozonized coconut oil with ethanol) are characterized and compared statistically. Peroxide, acidity and viscosity indexes were determined. The reaction products were identified by 1H NMR and their antimicrobial activity was evaluated. The ozonized coconut oil with ethanol showed the highest peroxide and acidity indexes. This result suggests that in presence of ethanol a greater peroxide decomposition occurs leading to greater acid formation. The variation coefficients obtained in the analysis methods were smaller than 10%. Reaction products were identified as ozonides and aldehydes compounds. The highest action spectrum of antimicrobial activity by Staphylococcus aureus was obtained with the ozonized coconut oil with water and ethanol systems.