Cardiovascular response during trigeminal ganglion compression for trigeminal neuralgia according to the use of local anesthetics

There are controversies about the use of local anesthetics during balloon compression for trigeminal neuralgia (TN) as a protective factor for cardiovascular events. The objective of this study was to investigate cardiovascular parameters (blood pressure and heart rate [HR]) of patients that underwent trigeminal balloon compression with local anesthetics compared to a control group (placebo). This is a randomized controlled study; 55 patients were randomized into two groups: study (deep sedation and trigeminal block with 0.8-mL lidocaine 2%) and control group (deep sedation and trigeminal injection of 0.8-mL saline). Blood pressure and HR were measured in five distinct moments: preoperative, during puncture for local anesthesia/placebo, during puncture with the catheter, during balloon compression, and final evaluation. Statistical analysis was performed with Pearson`s chi (2) and McNemar tests and the analysis of variance for repetitive measures. The means of systolic and diastolic blood pressures (SBP and DBP, respectively) were higher in the control group when compared to the study group at the evaluation during puncture with the catheter (p < 0.001) and balloon compression (p < 0.001 and p = 0.018 for DBP and SBP, respectively). There was an increase in the HR in the control group during the procedure (p = 0.017). The use of local anesthetics during the trigeminal balloon compression for TN can have a preventive role for the risk of cardiovascular events.

Hydration and N-acetylcysteine in acute renal failure caused by iodinated contrast medium: an experiment with rats

Background: The involvement of nephrotoxic agents in acute renal failure (ARF) has increased over the last few decades. Among the drugs associated with nephrotoxic ARF are the radiologic contrast media whose nephrotoxic effects have grown, following the increasing diagnostic use of these agents. Methods: We evaluated the effect of iodinated contrast (IC) medium, administered in combination, or not, with hyperhydration or N-acetylcysteine (NAC), on creatinine clearance, production of urinary peroxides and renal histology of rats. Adult Wistar rats treated for 5 days were divided into the following groups: control (saline, 3 ml/kg/day, intraperitoneally [i.p.]), IC (sodium iothalamate meglumine, 3 ml/kg/day i.p.), IC + water (12 mL water, orally + IC, 3 ml/kg/day i.p. after 1 hour), IC + NAC (NAC, 150 mg/kg/day, orally + IC, 3 ml/kg/day i.p. after 1 hour) and IC + water + NAC. Results: IC medium reduced renal function, with maintenance of urinary flow. Hyperhydration did not reduce the nephrotoxic effect of the IC agent, which was observed in the group IC + NAC. The combination of hyperhydration and NAC had no superior protective effect compared with NAC alone. An increase in urinary peroxides was observed in the IC group, with NAC or water or the combination of both reducing this parameter. Histopathologic analysis revealed no significant alterations. Conclusions: In summary, given 5 days previously, NAC was found to be more effective than hyperhydration alone in the prevention of contrast-induced acute renal failure.

Intracellular mechanisms of specific beta-adrenoceptor antagonists involved in improved cardiac function and survival in a genetic model of heart failure

beta-blockers, as class, improve cardiac function and survival in heart failure (HF). However, the molecular mechanisms underlying these beneficial effects remain elusive. In the present study, metoprolol and carvedilol were used in doses that display comparable heart rate reduction to assess their beneficial effects in a genetic model of sympathetic hyperactivity-induced HF (alpha(2A)/alpha(2C)-ARKO mice). Five month-old HF mice were randomly assigned to receive either saline, metoprolol or carvedilol for 8 weeks and age-matched wild-type mice (WT) were used as controls. HF mice displayed baseline tachycardia, systolic dysfunction evaluated by echocardiography, 50% mortality rate, increased cardiac myocyte width (50%) and ventricular fibrosis (3-fold) compared with WT. All these responses were significantly improved by both treatments. Cardiomyocytes from HF mice showed reduced peak [Ca(2+)](i) transient (13%) using confocal microscopy imaging. Interestingly, while metoprolol improved [Ca(2+)](i) transient, carvedilol had no effect on peak [Ca(2+)](i) transient but also increased [Ca(2+)] transient decay dynamics. We then examined the influence of carvedilol in cardiac oxidative stress as an alternative target to explain its beneficial effects. Indeed, HF mice showed 10-fold decrease in cardiac reduced/oxidized glutathione ratio compared with WT, which was significantly improved only by carvedilol treatment. Taken together, we provide direct evidence that the beneficial effects of metoprolol were mainly associated with improved cardiac Ca(2+) transients and the net balance of cardiac Ca(2+) handling proteins while carvedilol preferentially improved cardiac redox state. (C) 2008 Elsevier Inc. All rights reserved.

Morphological analysis of pitting corrosion in AISI 310S austenitic stainless steel after salt spray exposition

This paper aims to study evolution of increase, distribution and classification of pits in 310S austenitic stainless steels obtained in the state as-received and heat-treated under different exposure times in saline. This work applicability has been based on a technique development for morphologic characterization of localized corrosion associated with description aspects of shapes, size and population-specific parameters. Methodology has been consisted in the following steps: specimens preparation, corrosion tests via salt spray in different conditions, microstructural analysis, pits profiles analysis and images analysis, digital processing and image analysis in order to characterize the pits distribution, morphology and size. Results obtained in digital processing and profiles image analysis have been subjected to statistical analysis using median as parameter in the alloy as received and treated. The alloy as received displays the following morphology: hemispheric pits> transition region A> transition region B> irregular> conic. The pits amount in the treated alloy at each exposure time is: transition region B> hemispherical> transition region A> conic> irregular.

Lumbar Epidural Anesthesia in the Treatment of Discal Lombosciatalgia: A Comparative Clinical Study between Methylprednisolone and Methylprednisolone with Levobupivacaine

Sousa FAEF, Colhado OCG - Lumbar Epidural Anesthesia in the Treatment of Discal Lombosciatalgia: A Comparative Clinical Study between Methylprednisolone and Methylprednisolone with Levobupivacaine. Background and objectives: Lumbar epidural technique has been used in the treatment of lombosciatalgia since 1953. In most cases, methylprednisolone is used along with a local anesthetic, and it is not known whether the isolated use of methylprednisolone is equally effective in relieving symptoms. The objective of this study was to compare the efficacy of two different solutions - methylprednisolone with saline and methylprednisolone with levobupivacaine injected in the epidural space to heal lombosciatalgia secondary to lumbar herniated disk. Methods: Sixty individuals ASA I and II, of both genders, ages 18 to 65 years participated in this randomized, double-blind study over a period of one year. They underwent interlaminar lumbar epidural analgesia without radioscopic control to heal a lombosciatalgia and they were divided into two groups: G-M (methylprednisolone + saline) and G-M + L (methylprednisolone + levobupivacaine + saline) both at a volume of 10 mL. Diagnosis was based on history, physical exam, and imaging exam (MRI). The Visual Analogue Scale (VAS) was applied in a total of two blockades, 15 days apart. Results: A reduction in pain severity was observed in the methylprednisolone-levobupivacaine group, but without statistical significance. Conclusions: The analgesic efficacy of the G-M + L solution was superior to that of the G-M solution in the treatment of discal lombosciatalgia regarding the shorter time to onset of analgesia, but this was not significant at the time of discharge, and both solutions were effective in the treatment of discal lombosciatalgia.

Desalination of water by reverse osmosis using gravitational potential energy and wind energy

This paper proposes ail alternative configuration to conventional reverse osmosis (RO) desalination systems by incorporating the use of gravitational potential energy. The proposal suggests a model that can be viewed as the energy station of a RO desalination plant. Conventionally, RO plants use a high-pressure pump, powered by electricity or fossil fuel. The function of the pump is to send a flux of saline water to a group of semi-permeable membrane modules, capable of ""filtering"" the dissolved salts. In this proposed model, we intend to achieve a flux at the inlet of the membrane modules with a pressure high enough for the desalination process, without using, either electricity or fossil fuels. To do this we divised a hybrid system that uses both gravitational potential energy and wind energy. The technical viability of the alternative was theoretically proven by deductions based on physics and mathematics.

Investigation of the mass transfer processes during the desalination of water containing phenol and sodium chloride by electrodialysis

Oxidation processes are used in wastewater treatment when conventional processes are not effective due to the presence of recalcitrant organic contaminants, like phenol. However, the presence of ionic compounds associated with organic pollutants may retard the oxidation. In this work the transport of species contained in an aqueous solution of phenol containing sodium chloride was evaluated in an electrodialysis (ED) system. An experimental study was carried out in which the influence of the process variables on the phenol loss and sodium chloride removal was investigated. Experiments were also performed without current, in order to determine the phenol transfer due to diffusion. The phenol and salt concentration variations in the ED compartments were measured over time, using dedicated procedures and an experimental design to determine the global characteristic parameters. A phenomenological approach was used to relate the phenol, salt and water fluxes with the driving forces (concentration and electric potential gradients). Under ED conditions, two contributions were pointed out for the phenol transport, i.e. diffusion and convection, this latter coming from the water flux due to electroosmosis related to the migration of salts. The fitting of the parameters of the transport equations resulted in good agreement with the experimental results over the range of conditions investigated. (c) 2008 Elsevier B.V. All rights reserved.

In Vitro and In Vivo Evaluation of Lyophilized Bioprosthetic Valve

Freeze-drying of biological tissues allows for dry storage and gamma ray sterilization, which may improve their use as a medical prosthesis. The objective of this study was to evaluate the rehydration characteristics and hydrodynamic performance of prosthetic valves before and after lyophilization. Two size 23 bovine pericardium aortic valve prostheses from different manufacturers were evaluated in a Shelhigh (Union, NJ, USA) pulse duplicator (80 ppm, 5 L/min) before and after lyophilization. Flow and transvalvular pressure gradient were registered in vitro and in vivo, and images of opening and closing of the prosthesis were obtained in the pulse duplicator in a digital camera. Rehydration was evaluated by comparison of dry valve weight with valve weight after 15 min, and 1, 24, 48, and 72 h in saline solution, inside the pulse duplicator. In vivo performance was assessed by surgical implantation in Santa Ines young male sheep in the pulmonary position after 30 min rehydration with 0.9% saline. Transvalvular pressure gradient and flow measurements were obtained immediately after implantation and 3 months after surgery when valves were explanted. Captured images showed a change in the profile opening and closing of valve prosthesis after lyophilization. The gradient measured (in vitro) in two valves was 17.08 +/- 0.57 and 18.76 +/- 0.70 mm Hg before lyophilization, and 34.24 +/- 0.59 and 30.40 +/- 0.97 mm Hg after lyophilization. Rehydration of both lyophilized valves was approximately 82%. Drying changed the profile of the opening and closing of valve prostheses, and increased on average by 83% the gradient in vitro tests. The result of the in vivo tests suggests maintaining pressure levels of the animal with the lyophilized prostheses within acceptable levels.

Root Water Extraction under Combined Water and Osmotic Stress

Using a numerical implicit model for root water extraction by a single root in a symmetric radial flow problem, based on the Richards equation and the combined convection-dispersion equation, we investigated some aspects of the response of root water uptake to combined water and osmotic stress. The model implicitly incorporates the effect of simultaneous pressure head and osmotic head on root water uptake, and does not require additional assumptions (additive or multiplicative) to derive the combined effect of water and salt stress. Simulation results showed that relative transpiration equals relative matric flux potential, which is defined as the matric flux potential calculated with an osmotic pressure head-dependent lower bound of integration, divided by the matric flux potential at the onset of limiting hydraulic conditions. In the falling rate phase, the osmotic head near the root surface was shown to increase in time due to decreasing root water extraction rates, causing a more gradual decline of relative transpiration than with water stress alone. Results furthermore show that osmotic stress effects on uptake depend on pressure head or water content, allowing a refinement of the approach in which fixed reduction factors based on the electrical conductivity of the saturated soil solution extract are used. One of the consequences is that osmotic stress is predicted to occur in situations not predicted by the saturation extract analysis approach. It is also shown that this way of combining salinity and water as stressors yields results that are different from a purely multiplicative approach. An analytical steady state solution is presented to calculate the solute content at the root surface, and compared with the outputs of the numerical model. Using the analytical solution, a method has been developed to estimate relative transpiration as a function of system parameters, which are often already used in vadose zone models: potential transpiration rate, root length density, minimum root surface pressure head, and soil theta-h and K-h functions.

Paclitaxel associated with cholesterol-rich nanoemulsions promotes atherosclerosis regression in the rabbit

A cholesterol-rich nanoemulsion (LDE) that resembles LDL binds to the LDL receptors and after injection into the blood stream may concentrate in cells with LDL receptor overexpression, as occurs in neoplasias and other proliferative processes. Thus, LDE can be used as vehicle to target drugs against those cells. The current study was designed to verify in rabbits whether LDE concentrates in the lesioned rabbit artery and whether a paclitaxel derivative, paclitaxel oleate, associated to LDE could reduce the atherosclerotic lesions. Sixteen male New Zealand rabbits were fed a 1% cholesterol diet for 60 days. Starting from day 30 under cholesterol feeding, eight animals were treated with four weekly intravenous injections of LDE-paclitaxel (4 mg/kg) and eight with four weekly intravenous saline solution injections for additional 30 days. On day 60, the animals were sacrificed for analysis. The uptake of LDE labeled with [C-14]-cholesteryl oleate by the aortic arch of cholesterol-fed rabbits was twice as much that observed in animals fed only regular chow. LDE-paclitaxel reduced the lesion areas of cholesterol-fed animals by 60% and intima-media ratio fourfold and inhibited the macrophage migration and the smooth muscle cell proliferation and invasion of the intima. LDE-paclitaxel treatment had no toxicity. In conclusion, LDE-paclitaxel produced pronounced atherosclerosis regression without toxicity and has shown remarkable potential in cardiovascular therapeutics. (c) 2008 Published by Elsevier Ireland Ltd.

Malnourished mice display an impaired hematologic response to granulocyte colony-stimulating factor administration

The aim of this Study was to determine if protein-energy malnutrition Could affect the hematologic response to granulocyte colony-stimulating factor (G-CSF). Swiss mice were fled a low-protein diet containing 4% protein, whereas control mice were fed a 20% protein-containing diet. After the malnourished group lost 20% of their original body weight, the mice were subdivided in 2 treatment groups, and hematopoietic parameters were studied. Mice were injected with either 8 mu g/kg per day of G-CSF or saline twice daily for 4 days. Malnourished mice developed anemia with reticulopenia and leukopenia with depletion of granulocytes and lymphocytes. Both malnourished and control mice treated with G-CSF showed a significant increase in neutrophils; however, in the control group, this increase was more pronounced compared to the malnourished group (4.5-fold and 3.4-fold, respectively). Granulocyte colony-stimulating factor administration increased bone marrow blastic (P < .001) and granulocytic (P < .01) compartments in the controls bill had no significant effect oil these hematopoietic compartments in the Malnourished animals (P = .08 and P = .62, respectively). We report that malnourished mice display an impaired response to G-CSF, which contributes to the decreased production of leukocytes in protein-energy malnutrition. (C) 2008 Elsevier Inc. All rights reserved.

An evaluation, using the comet assay and the micronucleus test, of the antigenotoxic effects of chlorophyll b in mice

We investigated the effects of the dietary pigment chlorophyll b (CLb) on cisplatin (cDDP)-induced oxidative stress and DNA damage, using the comet assay in mouse peripheral blood cells and the micronucleus (MN) test in bone marrow and peripheral blood cells. We also tested for thiobarbituric acid reactive substances (TBARS) and reduced glutathione (GSH) in liver and kidney tissues, as well as catalase (CAT) activity and GSH in total blood. CLb (0.2 and 0.5 mg/kg b.w.) was administrated by gavage every day for 13 days. On the 14th day of the experiment, 6 mg/kg cDDP or saline was delivered intraperitoneally. Treatment with cDDP led to a significant decrease in DNA migration and an increase in MN frequency in both cell types, bone marrow and peripheral blood cells. In the kidneys of mice treated with cDDP, TBARS levels were increased, whereas GSH levels were depleted in kidney and liver. In mice that were pretreated with CLb and then treated with cDDP, TBARS levels maintained normal concentrations and GSH did not differ from cDDP group. The improvement of oxidative stress biomarkers after CLb pre-treatment was associated with a decrease in DNA damage, mainly for the highest dose evaluated. Furthermore, CLb also slightly reduced the frequency of chromosomal breakage and micronucleus formation in mouse bone marrow and peripheral blood cells. These results show that pre-treatment with CLb attenuates cDDP-induced oxidative stress, chromosome instability, and lipid peroxidation. (C) 2011 Elsevier B.V. All rights reserved.

Curcumin could prevent methemoglobinemia induced by dapsone in rats

The curcumin`s effect given orally by gavage in single- or multiple-dose regimens on methemoglobinemia induced by dapsone (DDS) was investigated in male Wistar rats. In the single-dose regimen, groups of 10 rats received either vehicle alone, or curcumin at 0.1, 1.0, 10, or 30 mg/kg body weight (bw), or curcumin at 0.02, 0.1, 1, 10, or 30 mg/kg bw plus DDS at 40 mg/kg bw, intraperitoneally (i.p.), 2 hours after. In the multiple-dose regimen, groups of 10 rats received either vehicle alone, or curcumin at 0.1, 1.0, 10, or 30 mg/kg bw for 5 days, with or without DDS (40 mg/kg bw, i.p.) 2 hours after on the fifth day. In both regimens, further groups of 10 rats were given DDS alone (positive controls) or normal saline (negative controls) i.p. Single-dose treatment with curcumin at 0.02 and 0.1 mg/kg bw significantly reduced DDS-induced methemoglobin formation, while the higher doses showed a pro-oxidant effect, significantly increasing DDS-induced methemoglobinemia. In the multiple-dose regimen, treatment with curcumin at 0.1 mg/kg bw significantly reduced DDS-induced methemoglobin formation, but the higher doses were without significant effect compared to DDS alone. It is concluded that curcumin at low doses mitigates methemoglobinemia induced by dapsone in rats, both in single- and multiple-dose regimens. (C) 2011 Elsevier Ltd. All rights reserved.

Metal embryotoxicity from urban particles in Sao Paulo city: An experimental study in chicken embryos

Chicken eggs were inoculated with suspensions of ambient air particles (<= 10 mu m, PM(10)) from Sao Paulo city in 3, 0.3 or 0.03 mu g doses on one of the four early days of embryo development. On the eleventh day of development alterations were observed on embryos inoculated with PM(10) 3 mu g on the third day. Particles analysis showed high content of metals. Hence, embryos were also inoculated with PM(10) (3 mu g) combined with metal chelating EDTA. PM(10) (3 mu g) embryos presented underdevelopment (stage 29.44 +/- 11.4) compared to vehicle and positive controls (stage 36.44 +/- 0.51 Saline and stage 31.20 +/- 9.7 Cyclophosphamide, p <= 0.05); higher (47%) mortality rate (23% Saline and 42% Cyclophosphamide) and low (68%) viability (100% Saline and 70% Cyclophosphamide, p = 0.04). Effects were attenuated when embryos received PM(10) + EDTA (stage 33.63 +/- 0.94, 18.9% mortality rate and 82% viability). PM(10) from Sao Paulo city is embryotoxic and metal may be implicated in the toxic mechanism. (C) 2010 Elsevier Inc. All rights reserved.

Growth Response of Various Perennial Grasses to Increasing Salinity

Although the effect of salinity on plant growth has been the focus of a substantive research effort, much of this research has failed to adequately separate the various growth limiting aspects of salinity; thus the results are confounded by multiple factors. Eight perennial grass species were grown in a sand culture system dominated by NaCl (electrical conductivities (ECs) between 1.4 and 38 dS m 1), with sufficient Ca added to each treatment to ensure that Na-induced Ca deficiency did not reduce growth. Of the eight perennial grass species examined, Chloris gayana cv. Pioneer (Rhodes grass) was the most salt tolerant species, whilst in comparison, Chrysopogon zizanioides cv. Monto (vetiver) was of only moderate tolerance. However, observed salinity tolerances tended to be lower than those expected from published values based on the threshold salinity model (bent stick model). This discrepancy may be due in part to differences in the evapotranspirational demand between studies; an increase in demand accelerating the accumulation of Na in the shoots and hence decreasing apparent salinity tolerance. It was also observed that the use of a non-saline growth period to allow seed germination and establishment results in the overestimation of vegetative salinity tolerance if not taken into consideration. This is particularly true for species of low salt tolerance due to their comparatively rapid growth in the non-saline medium compared to that at full salinity.