Attractive Effect of a Strong Electronic Repulsion: The Physics of Vertex Divergences.

While the breakdown of the perturbation expansion for the many-electron problem has several formal consequences, here we unveil its physical effect: flipping the sign of the effective electronic interaction in specific scattering channels. By decomposing local and uniform susceptibilities of the Hubbard model via their spectral representations, we prove how entering the nonperturbative regime causes an enhancement of the charge response, ultimately responsible for the phase-separation instabilities close to the Mott metal-insulator transition. Our analysis opens a new route for understanding phase transitions in the nonperturbative regime and clarifies why attractive effects emerging from a strong repulsion can induce phase separations but not s-wave pairing or charge-density wave instabilities.

Safety, pitfalls, and misunderstandings about the use of ozone therapy as a regenerative medicine tool. A narrative review.

Despite various opinions and healthy controversy on Ozone Therapy (OT), the practices of this therapy have increased worldwide. Main areas of study with consistent scientific outcomes are the topical treatment of both disk herniation and periodontal disease. On the other hand, there is a net dissociation of the scientific resonance concerning systemic oxygen/ozone treatments. It is our intention to discuss in logical terms the numerous papers that commendably reported adverse reactions attributable to OT, focusing our attention mainly to the techniques of administration and not to the simple contact of ozone with biological material. The case reports on OT treatments safety concerns discussed on international journals, make it possible to state that most safety issues are secondary to infections or traumatic reactions due to malpractice. Commonly, the molecule of ozone itself is not responsible of severe reactions at the therapeutic modalities. The millions of patients treated so far from the thousands of physicians correctly practicing OT world widely in the last 40 years demonstrate the safety of this simple and cost-effective regenerative medicine tool. The promising therapeutic implications also for the current COVID-19 emergency are a further stimulus to the standardization of this therapeutic resource with multiple application specificities.

Oxygen-ozone therapy as adjuvant in the current emergency in SARS-COV-2 infection: a clinical study.

The aim of the multicentre study promoted by Nuova FIO is to evaluate the beneficial effects of the systemic Oxygen-Ozone (O2O3) therapy in patients suffering from SARS COV-2 disease in the early phases of the disease, before worsening, up to the need of tracheal intubation. The study is based on the rationale on that the systemic oxygen-ozone treatment could be effective, positively influencing the disease evolution and/or being able to mitigate the onset of the cytokine storm syndrome at least partially.

Non cross-linked equine collagen (Salvecoll-E gel) for treatment of complex ano-rectal fistula.

BACKGROUND: Fistula-in-ano is one of the most commonly presenting anorectal diseases. Sphincter sparing treatment options should be considered in patients with complex fistulas. Salvecoll-E gel is a native collagen deantigenated and purified, non-cross-linked equine dermal extract, with an amino acid composition identical to human collagen. METHODS: The multicentric trial study was a prospective, single-arm observational clinical study with the objective to assess the efficacy of Salvecoll-E gel for anal fistula repair in 70 patients. All patients had undergone preliminary surgical treatment consisting of positioning of a draining loosing seton that was maintained for a period of 4-6 weeks. After seton removal, a gentle debridement and washing of the fistula track was performed. The scar tissue was removed from the internal orifice. Internal opening was covered by a side-to side mucosal suture. Salvecoll-E was injected through the external opening into the fistula track, the external opening it has been opened. RESULTS: Twelve months after surgery, 55 patients demonstrated a clinically healed fistula (78,5%), 15 patients have a recurrence (21,5%). Most of the recurrences were observed in the first 6 months of treatment (13/15, 86.6%). We don't observe any worsening in CCF score. The results obtained at 1 year certainly seem satisfactory and in line with the best results published in literature using mini-invasive techniques. CONCLUSION: Salvecoll-E gel is a promising non-invasive technique for conservative treatment of anal fistulas, it's well tolerated by the patients and, in case of recurrence, reinjection or all other known techniques are feasible.

Nueva forma de presentación de la lepra lepromatosa en forma de patrón Prurigoide: descripción de un caso / No disponible

La lepra puede presentar diversas y complejas manifestaciones clínicas. Las lesiones cutáneas más frecuentemente encontradas son: máculas, pápulas, placas, nódulos y tubérculos. El propósito de esta comunicación es resaltar una forma de presentación atópica de lepra lepromatosa, en un adulto joven de sexo masculino, cuya lesiones iniciales eran pápulas excoriadas en superficie simulando una urticaria papular/prurigo simple. En este caso en particular, la anatomía patológica fue determinante para el diagnóstico correcto. Hacemos hincapié en que la lepra lepromatosa es una «gran simuladora» y los clínicos deberían estar alertas ante estas formas de manifestación rara, que ocurren en ciertas regiones endémicas

Leprosy may have diverse and complex clinical manifestations. Skin lesions most commonly found are: macules, papules, plaques, nodules and tubers. The purpose of this communication is to highlight a form of atypical presentation of lepromatous leprosy, in a young adult male, whose initial lesions were excoriated papules on surface simulating a prurigo/papular urticaria. In this particular case, the pathology was decisive for correct diagnosis. We emphasize that lepromatous leprosy is a great imitator and clinicians should be aware of these rare forms of manifestation, occurring in certain endemic areas

Moral distress in the neonatal intensive care unit: an Italian study.

OBJECTIVE: The objective of this study was to evaluate the frequency, the intensity and the level of moral distress experienced by nurses working in neonatal intensive care units (NICUs). STUDY DESIGN: We conducted a cross-sectional questionnaire survey involving 472 nurses working in 15 level III NICUs. Frequency, intensity and level of moral distress was evaluated using a modified version of Moral Distress Scale Neonatal-Pediatric Version. Socio-demographic data were also collected. RESULT: Four hundred six nurses completed the study material indicating a low-to-moderate experience of moral distress. The situations receiving the highest scores for frequency, intensity and level of moral distress related to the initiation of extensive life-saving actions and participation to the care of ventilator-dependent child. No difference in the mean scores of moral distress was found according to the socio-demographic characteristics investigated. CONCLUSION: The present study provides further insight into the moral distress experienced by nurses working in Italian NICUs.

Ascertainment bias in dementias: a secondary to tertiary centre analysis in Central Italy and conceptual review.

BACKGROUND AND AIMS: Ascertainment bias (AB) indicates a bias of an evaluation centre in estimating the prevalence/incidence of a disease due to the specific expertise of the centre. The aim of our study was to evaluate classification of different types of dementia in new cases appearing in secondary and tertiary centres, in order to evidence possible occurrence of AB in the various (secondary to tertiary) dementia centres. METHODS: To assess the mechanism of AB, the rates of new cases of the different forms of dementia reported by different centres were compared. The centres involved in the study were 11 hospital-based centres including a tertiary centre, located in the University Department of Clinical Neurology. The tertiary centre is endowed with state-of-the-art diagnostic facilities and its scientific production is prominently focused on dementia with Lewy bodies (DLB) thus suggesting the possible occurrence of a bias. Four main categories of dementia were identified: Alzheimer's disease (AD), DLB, fronto-temporal dementia (FTD), vascular dementia (VaD), with other forms in a category apart. The classification rate of new cases of dementia in the tertiary centre was compared with rates reported by secondary centres and rates of recoding were calculated during a follow-up of 2 years. RESULTS: The study classified 2,042 newly diagnosed cases of dementia in a population of 1,370,000 inhabitants of which 315,000 were older than 65. AD was categorized in 48-52 % of cases, DLB in 25-28 %, FTD in 2-4 % and VaD in 17-28 %. During the 2-year follow-up the diagnosis was re-classified in 40 patients (3 %). The rate of recoding was 5 % in the tertiary centre, 2-8 % in referrals from secondary to tertiary centre, 2-10 % in recodings performed in secondary centres and addressed to tertiary centre. Recoding or percentages of new cases of AD or DLB were not different in the comparison between secondary or between secondary and tertiary centres. FTD and VaD were instead significantly recoded. CONCLUSION: The results of the study suggest that in a homogeneous area, AB is not interfering with diagnosis of AD or DLB.

Monoterapia biológica en pacientes con artritis reumatoidea en Argentina / Biological monotherapy in patients with rheumatoid arthritis in Argentina

Introducción: La utilización de agentes biológicos para el tratamiento de la Artritis Reumatoidea (AR) es habitualmente usada en aquellos pacientes con enfermedad activa que no hayan respondido al tratamiento con drogas modificadoras de la Artritis Reumatoidea convencionales (DMARD, por sus siglas en inglés) o que hayan presentado intolerancia a las mismas. Al estado actual de la evidencia, la terapia combinada de agentes biológicos más un DMARD convencional (principalmente metotrexato) constituye el estándar de tratamiento. Sin embargo existen algunos escenarios como la intolerancia, la falta de adherencia y la aparición de eventos adversos a las DMARDs convencionales donde la monoterapia biológica emerge como una opción terapéutica válida. Según los distintos registros a nivel internacional, la frecuencia de utilización de agentes biológicos en monoterapia oscila entre 12 a 39%. Debido a la ausencia de estos datos a nivel local decidimos realizar este estudio para conocer el porcentaje de pacientes que se encuentran en monoterapia biológica y analizar las causas que llevaron a este tipo de tratamiento. Materiales y métodos: Estudio de tipo corte transversal donde se invitó a participar a diferentes centros reumatológicos distribuidos a lo largo de Argentina. Cada centro revisó las historias clínicas de los últimos 30 a 50 pacientes consecutivos vistos con AR, mayores de 18 años, que habían presentado inadecuada respuesta al tratamiento con DMARDs y que estaban bajo tratamiento biológico. Se completaba una ficha por cada paciente incluido, registrando datos demográficos, de la enfermedad y tratamientos previos. Resultados: Se incluyeron 32 centros y se evaluaron 1148 historias clínicas de pacientes con AR durante el mes de octubre y noviembre del 2012. Un 21,4% (246) de los pacientes al momento del estudio se encontraba bajo tratamiento biológico en monoterapia...

Introduction: The use of biological agents for the treatment of rheumatoid arthritis (RA) is commonly used in patients with active disease who have not responded to treatment with conventional rheumatoid arthritis-modifying drugs (DMARDs) or Who have presented intolerance to them. At the present state of evidence, combined therapy of biological agents plus conventional DMARD (mainly methotrexate) is the standard of treatment. However, there are some scenarios such as intolerance, lack of adherence and the appearance of adverse events to conventional DMARDs where biological monotherapy emerges as a valid therapeutic option. According to different international registries, the frequency of use of biological agents in monotherapy ranges from 12 to 39%. Due to the absence of these data at the local level we decided to carry out this study to know the percentage of patients who are in biological monotherapy and to analyze the causes that led to this type of treatment. Materials and methods: A cross-sectional study where different rheumatologic centers throughout Argentina were invited to participate. Each center reviewed the medical records of the last 30 to 50 consecutive patients seen with RA, older than 18 years, who had inadequate response to treatment with DMARDs and who were under biological treatment. One card was completed for each patient included, recording demographic, disease and previous treatment data. Results: Thirty-two centers were included and 1148 clinical records of patients with RA were evaluated during October and November 2012. A total of 244 patients (246) at the time of the study were under monotherapy...

National survey of anemia prevalence after kidney transplantation in Argentina.

Anemia is prevalent in kidney transplant recipients and likely contributes to morbidity and mortality. The definition of anemia as established by the World Health Organization and subsequently adopted by the American Society of Transplantation is a hemoglobin concentration of 12 g/dL or less in women and 13 g/dL or less in men. Using this definition, the prevalence of anemia is nearly 30%. The National Survey of Post Transplant Anemia (PTA) in kidney transplant recipients in Argentina was conducted to evaluate the incidence of PTA at 1 year and its relationship to variables that influence transplantation outcome. At 1 year posttransplantation, mean (SD) hemoglobin concentration was 12.43 (1.77) g/dL (n = 379), hematocrit concentration was 38.26% (5.59%) (n = 379), serum creatinine concentration was 1.51 (0.72) mg/dL (n = 380), and creatinine clearance was 60.8 (22.47) mL/min (n = 334). The prevalence of PTA in Argentina at 1 year posttransplantation was 42.25%. At univariate analysis, female sex, immunosuppression regimen (mycophenolate mofetil plus mammalian target of rapamycin), and pediatric age group were associated with anemia. At multivariate analysis, only renal function and pediatric age group were associated with anemia. The mean hemoglobin level at year of transplant was 12.43 g/dL +/-1.77 and the prevalence of PTA in Argentina at year of transplant is 42.25%. Results of our survey show a correlation between Hb levels and graft function and pediatric recipient.

Ozone as u-shaped dose responses molecules (hormetins).

Redox environment involves a broad network of pro-oxidant and antioxidant components. Health benefit or damage can be induced as a consequence of an adaptive cellular stress response. A consequence of hormetic amplification is an increase in the homeodynamic space of a living system in terms of an increased defense capacity and a reduced load of damaged macromolecules. Ozone, when used at appropriate doses, promotes the formation of reactive oxygen species and lipid peroxides allows them to become late and long-lasting messengers. Healthy aging may be achieved by hormesis through mild and periodic, but not severe or chronic, physical and mental challenges, and by the use of nutritional hormesis incorporating mild stress-inducing molecules called hormetins. The paradoxical concept that ozone eventually induces an antioxidant response capable of reversing a chronic oxidative stress is common in the animal and vegetal kingdom; it is already supported by findings of an increased level of antioxidant enzymes during ozone therapy. Those facts can include ozone as a hormetin. The established scientific foundations of hormesis are ready to pave the way for new and effective approaches in redox-related disease research and intervention; ozone therapy can be a good candidate.

Results of a prospective allocation policy of expanded criteria donors kidneys based on clinical parameters.

The ideal system to allocate expanded criteria donors (ECD) kidneys has not been fully elucidated. In a previous retrospective study, we reported that donor clinical characteristics were more predictive of transplant outcome than biopsy findings. Subsequently, we decided to use ECD kidneys solely based on a clinical scoring system. To elucidate the value of the pre-transplant biopsy, the patients were divided in two groups according to the suitability of the kidney they received for single or double transplantation as determined by a histological scoring system (HS). All kidneys were transplanted as a single (vs. dual) transplant. We studied whether a HS of the pre-transplant biopsy was predictive of outcome of single transplant ECD kidneys. Recipients (n = 48) were divided into two groups by whether the histologic system suggested single or double transplants be done. There were no differences between groups in two-yr outcomes. We conclude that a clinical scoring system can predict which ECD kidney donors can be safely used as single transplants in a cohort of low immunological risk de novo kidney transplant recipients. Use of the clinical scoring system maximizes organ use.

Aflatoxin B1 misregulates the activity of serine proteases: possible implications in the toxicity of some mycotoxin.

Aflatoxins are highly hazardous contaminants of common food and feed. Aflatoxin B1 in particular, the most predominant among aflatoxins, was thoroughly demonstrated to be highly toxic, mutagenic, teratogenic and carcinogenic in many animal species. Besides its established targets and effects, this work investigates on the possible direct interaction between aflatoxin B1 and three major serine proteases, namely elastase, thrombin and trypsin. These proteases belongs to a class of structurally and functionally related proteins pivotal in both direct and indirect regulation of a number of cellular events. Additionally, several pathological processes, including cancer, inflammatory processes and thrombosis, rely upon the subtle equilibrium between these enzymes and their potential modulators: in fact, their misregulation, caused by foreign molecules, could facilitate (or be the cause for) the occurrence of these pathologies. Our results provide the evidence for a reversible binding between AFB1 and these enzymes, likely to have profound implications in the manifestation of aflatoxicosis. Precisely, the toxin behaved as a moderate competitive inhibitor toward the enzymatic activity of the serine proteases in the low micromolar range.

Purification and n-terminal sequencing of two presynaptic neurotoxic PLA2, neuwieditoxin-I and neuwieditoxin-II, from Bothrops neuwiedi pauloensis (jararaca pintada) venom

Two presynaptic phospholipases A2 (PLA2), neuwieditoxin-I (NeuTX-I) and neuwieditoxin-II (NeuTX-II), were isolated from the venom of Bothrops neuwiedi pauloensis (BNP). The venom was fractionated using molecular exclusion HPLC (Protein-Pak 300SW column), followed by reverse phase HPLC (æBondapak C18 column). Tricine-SDS-PAGE in the presence or absence of dithiothreitol showed that NeuTX-I and NeuTX-II had a molecular mass of approximately 14 kDa and 28kDa, respectively. At 10æg/ml, both toxins produced complete neuromuscular blockade in indirectly stimulated chick biventer cervicis isolated preparation without inhibiting the response to acetylcholine, but NeuTX-II reduced the response to KCl by 67.0±8.0 percent (n=3; p<0.05). NeuTX-I and NeuTX-II are probably responsible for the presynaptic neurotoxicity of BNP venom in vitro. In fact, using loose patch clamp technique for mouse phrenic nerve-diaphragm preparation, NeuTX-I produced a calcium-dependent blockade of acetylcholine release and caused appearance of giant miniature end-plate potentials (mepps), indicating a pure presynaptic action. The N-terminal sequence of NeuTX-I was DLVQFGQMILKVAGRSLPKSYGAYGCYCGWGGRGK (71 percent homology with bothropstoxin-II and 54 percent homology with caudoxin) and that of NeuTX-II was SLFEFAKMILEETKRLPFPYYGAYGCYCGWGGQGQPKDAT (92 percent homology with Basp-III and 62 percent homology with crotoxin PLA2). The fact that NeuTX-I has Q-4 (Gln-4) and both toxins have F-5 (Phe-5) and Y-28 (Tyr-28) strongly suggests that NeuTX-I and NeuTX-II are Asp49 PLA2.

Results of a calcineurin-inhibitor-free immunosuppressive protocol in renal transplant recipients of expanded criteria deceased donors.

The increasing number of patients on waiting lists and the relatively stable organ procurement rate provide the groundwork for the use of expanded criteria deceased donors. While calcineurin-inhibitors (CNI) are excellent immunosuppressive drugs, their nephrotoxicity is largely responsible for the lack of improvement in long-term graft survival. The objective of this study was to analyze the results obtained with the use of a calcineurin inhibitor-free immunosuppressive protocol (polyclonal antibody induction, plus sirolimus, mycophenolate mofetil, and low doses of steroids) in terms of graft and patient survival as well as posttransplant clinical complications over 2 years. Under this immunosuppressive protocol, 78.04% of the patients completed the follow-up. A protocol biopsy was performed on 17 patients (53.1%) within 2 years posttransplant of which 82.31% were diagnosed as chronic allograph nephropathy grade I. The incidence of clinical complications was low and not significantly different from that reported with other immunosuppressive schemes. Death-censored graft survival was 95.12%. In conclusion, the use of a calcineurin inhibitor-free protocol in renal-transplant recipients of expanded criteria deceased donors was associated with excellent graft and patient survival rates and a low incidence of adverse events.

Comparison between clinical and histopathological scoring in cadaveric kidney transplantation and its correlation with posttransplant evolution.

INTRODUCTION: There are several scoring systems, both clinical (Deceased Donor Score [DDS]) and histopathological (Remuzzi [REM]), that attempt to determine acceptability criteria for deceased donor kidney transplant. A retrospective study was performed among a group of kidney transplant recipients to evaluate posttransplant evolution with clinical and histopathological scores. MATERIALS AND METHODS: Among 107 first deceased donor kidney transplant patients, 95 had undergone a pretransplant biopsy. Donor age was 38.46 +/- 16.9 years; recipient age: 49.2 +/- 16.3 years; DDS was 15.58 +/- 7.29. REM was 2.89 +/- 1.7. Delayed graft function was 64.2%. Induction therapy was administered to 49.5%. Cold ischemia time (CIT) was 1364 +/- 348 minute. Time on dialysis was 2275 +/- 1501 days. Induction therapy, immunosuppressive regimens, CIT, and time on dialysis were not significantly different among the groups. One-year patient and graft survival were 94.5% and 86%, respectively and 2-year values, 92.6% and 81%, respectively. CONCLUSION: DDS showed a significant correlation with serum creatinine values over 1 and 2 years. REM did not show a significant association with any events. The differences were sustained after adjusting for other variables. Graft survival maintained a strong correlation with DDS categories and no association with REM. The clinical characteristics of a deceased donor appeared to be of greater importance than the biopsy findings in terms of posttransplant events.

Clostridium difficile colitis in patients after kidney and pancreas-kidney transplantation.

Limited data exist about Clostridium difficile colitis (CDC) in solid organ transplant patients. Between 1/1/99 and 12/31/02, 600 kidney and 102 pancreas-kidney allograft recipients were transplanted. Thirty-nine (5.5%) of these patients had CDC on the basis of clinical and laboratory findings. Of these 39 patients, 35 have information available for review. CDC developed at a median of 30 days after transplantation, and the patients undergoing pancreas-kidney transplantation had a slightly higher incidence of CDC than recipients of kidney alone (7.8% vs. 4.5%, P>0.05). All but one patient presented with diarrhea. Twenty-four patients (64.9%) were diagnosed in the hospital, and CDC occurred during first hospitalization in 14 patients (40%). Treatment was with oral metronidazole (M) in 33 patients (94%) and M+oral vancomycin (M+V) in 2 patients. Eight patients had recurrent CDC, which occurred at a median of 30 days (range 15-314) after the first episode. Two patients (5.7%) developed fulminant CDC, presented with toxic megacolon, and underwent colectomy. One of them died; the other patient survived after colectomy. CDC should be considered as a diagnosis in transplant patients with history of diarrhea after antibiotic use, and should be treated aggressively before the infection becomes complicated.

Effects of ozone oxidative preconditioning on nitric oxide generation and cellular redox balance in a rat model of hepatic ischaemia-reperfusion.

BACKGROUND: Many studies indicate that oxygen free-radical formation after reoxygenation of liver may initiate the cascade of hepatocellular injury. It has been demonstrated that controlled ozone administration may promote an oxidative preconditioning or adaptation to oxidative stress, preventing the damage induced by reactive oxygen species and protecting against liver ischaemia-reperfusion (I/R) injury. AIMS: In the present study, the effects of ozone oxidative preconditioning (OzoneOP) on nitric oxide (NO) generation and the cellular redox balance have been studied. METHODS: Six groups of rats were classified as follows: (1). sham-operated; (2). sham-operated+l-NAME (N(omega)-nitro-l-arginine methyl ester); (3). I/R (ischaemia 90 min-reperfusion 90 min); (4). OzoneOP+I/R; (5). OzoneOP+l-NAME+I/R; and (6). l-NAME+I/R. The following parameters were measured: plasma transaminases (aspartate aminotransferase, alanine aminotransferase) as an index of hepatocellular injury; in homogenates of hepatic tissue: nitrate/nitrite as an index of NO production; superoxide dismutase (SOD), catalase (CAT) and glutathione levels as markers of endogenous antioxidant system; and finally malondialdehyde+4-hydroxyalkenals (MDA+4-HDA) and total hydroperoxides (TH) as indicators of oxidative stress. RESULTS: A correspondence between liver damage and the increase of NO, CAT, TH, glutathione and MDA+4-HDA concentrations were observed just as a decrease of SOD activity. OzoneOP prevented and attenuated hepatic damage in I/R and OzoneOP+l-NAME+I/R, respectively, in close relation with the above-mentioned parameters. CONCLUSIONS: These results show that OzoneOP protected against liver I/R injury through mechanisms that promote a regulation of endogenous NO concentrations and maintenance of cellular redox balance. Ozone treatment may have important clinical implications, particularly in view of the increasing hepatic transplantation programs.

Protective effect of Mangifera indica L. extract (Vimang) on the injury associated with hepatic ischaemia reperfusion.

The effect of Mangifera indica L. extract (Vimang) on treatment of injury associated with hepatic ischaemia/reperfusion was tested. Vimang protects from the oxidative damage induced by oxygen-based free radicals as shown in several in vitro test systems conducted. The ability of Vimang to reduce liver damage was investigated in rats undergoing right-lobe blood fl ow occlusion for 45 min followed by 45 min of reperfusion. The ischaemia/reperfusion model leads to an increase of transaminase (ALT and AST), membrane lipid peroxidation, tissue neutrophil in filtration, DNA fragmentation, loss of protein -SH groups, cytosolic Ca2+ overload and a decrease of catalase activity. Oral administration of Vimang (50, 110 and 250 mg/kg, b.w.) 7 days before reperfusion, reduced transaminase levels and DNA fragmentation in a dose dependent manner (p < 0.05). Vimang also restored the cytosolic Ca2+ levels and inhibited polymorphonuclear migration at a dose of 250 mg/kg b.w., improved the oxidation of total and non protein sulfhydryl groups and prevented modification in catalase activity, uric acid and lipid peroxidation markers (p < 0.05). These data suggest that Vimang could be a useful new natural drug for preventing oxidative damage during hepatic injury associated with free radical generation.

Ozone treatment reduces markers of oxidative and endothelial damage in an experimental diabetes model in rats.

Ozone has been used as a therapeutical agent and beneficial effects have been observed. However so far only a few biochemical and pharmacodynamic mechanisms have been elucidated. We demonstrate that controlled ozone administration may promote an oxidative preconditioning or adaptation to oxidative stress, preventing the damage induced by reactive oxygen species (ROS). Taking into account that diabetes is a disorder associated with oxidative stress, we postulate that ozone treatment in our experimental conditions might protect antioxidant systems and maintain, at a physiological level, other markers of endothelial cell damage associated with diabetic complications. Five groups of rats were classified as follows: (1) control group treated only with physiological saline solution; (2) positive control group using streptozotocin (STZ) as a diabetes inductor; (3) ozone group, receiving 10 treatments (1.1 mg kg(-1)), one per day after STZ-induced diabetes; (4) oxygen group (26 mg kg(-1)), one per day, as in group 3 but using oxygen only; (5) control ozone group, as group 3, but without STZ. The ozone treatment improved glycemic control and prevented oxidative stress, the increase of aldose reductase, fructolysine content and advanced oxidation protein products. Nitrite and nitrate levels were maintained without changes with regard to non-diabetic control. The results of this study show that repeated administration of ozone in non-toxic doses might play a role in the control of diabetes and its complications.

Protective effects of Mangifera indica L. extract, mangiferin and selected antioxidants against TPA-induced biomolecules oxidation and peritoneal macrophage activation in mice.

We compared the protective abilities of Mangifera indica L. stem bark extract (Vimang) 50-250 mgkg(-1), mangiferin 50 mgkg(-1), vitamin C 100 mgkg(-1), vitamin E 100 mgkg(-1)and beta -carotene 50 mgkg(-1)against the 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced oxidative damage in serum, liver, brain as well as in the hyper-production of reactive oxygen species (ROS) by peritoneal macrophages. The treatment of mice with Vimang, vitamin E and mangiferin reduced the TPA-induced production of ROS by the peritoneal macrophages by 70, 17 and 44%, respectively. Similarly, the H(2)O(2)levels were reduced by 55-73, 37 and 40%, respectively, when compared to the control group. The TPA-induced sulfhydryl group loss in liver homogenates was attenuated by all the tested antioxidants. Vimang, mangiferin, vitamin C plus E and beta -carotene decreased TPA-induced DNA fragmentation by 46-52, 35, 42 and 17%, respectively, in hepatic tissues, and by 29-34, 22, 41 and 17%, in brain tissues. Similar results were observed in respect to lipid peroxidation in serum, in hepatic mitochondria and microsomes, and in brain homogenate supernatants. Vimang exhibited a dose-dependent inhibition of TPA-induced biomolecule oxidation and of H(2)O(2)production by peritoneal macrophages. Even if Vimang, as well as other antioxidants, provided significant protection against TPA-induced oxidative damage, the former lead to better protection when compared with the other antioxidants at the used doses. Furthermore, the results indicated that Vimang is bioavailable for some vital target organs, including liver and brain tissues, peritoneal exudate cells and serum. Therefore, we conclude that Vimang could be useful to prevent the production of ROS and the oxidative tissue damages in vivo.