925 resultados para saline hypertonique


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Chronic venous disease (CVD) is evident among the chronic diseases and affects the elderly population and primarily is responsible for leg ulcers in this population. The use of dressings in the care of a venous ulcer is a fundamental part of the treatment for healing, however, evidence to assist in choosing the best dressing is scarce. The main objective of this study was to evaluate the effectiveness of treatment with hydrogel in the healing of venous ulcers using search methods, synthesis of information and statistical research through a systematic review and meta-analysis. Randomized controlled trials were selected in the following databases: CENTRAL; DARE; NHS EED; MEDLINE; EMBASE; CINAHL. Beyond these databases three websites were consulted to identify ongoing studies: ClinicalTrials.gov, OMS ICTRP e ISRCTN. The primary outcomes were analyzed: complete wound healing, incidence of wound infection and the secondary were: changes in ulcer size, time to ulcer healing, recurrence of ulcer, quality of life of participants, pain and costs of treatment. Four studies are currently included in the review with a total of 250 participants. The use of hydrogel appears to be superior to conventional dressing, gauze soaked in saline, for the healing of venous leg ulcers; 16/30 patients showed complete healing of ulcers (RR 5,33, 95%CI [1,73,16,42]). The alginate gel was shown to be more effective when compared to the hydrogel dressing in reduction of the wound area; 61,2% (± 26,2%) with alginate e 19,4% (± 24,3%) with hydrogel at the end of four weeks of treatment. Manuka honey has shown to be similar to the hydrogel dressings in percentage of area reduction. This review demonstrated that there is no evidence available about the effectiveness of the hydrogel compared to other types of dressings on the healing of venous leg ulcers of the lower limbs, thus demonstrating the need of future studies to assist health professionals in choosing the correct dressing.

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The germination of cotton seeds and the seedlings emergency are generally delayed and reduced by the salinity. Although the cotton is considered a tolerant culture, it can suffer substantial reductions in regarding its growth and production when exposed to salinity condition. The aims of this study went evaluate the effect of the saline stress in the germination phase to four cotton genotypes (BRS Rubi, BRS Safira, BRS 201 and CNPA 187 8H), using different osmotic potentials generated with increment of sodium chloride (NaCl). The saline stress was simulated using NaCl aqueous solutions in the potentials: 0.0 (Control); -0.2; -0.4; -0.6; -0.8 and -1.0 MPa. The treatments were monitored by means of tests for analysis of seeds, germination, first counting, speed germination index, length of shoot, radicle length, dry weigth of embrionic axis and shoot/radicle ratio. The tests for germination, first counting and index of germination speed were accomplished using 50 seeds for repetition and for the study of length of shoot, radicle length, dry weigth of embrionic axis and shoot/radicle ratio were used 20 seeds by repetition. For both tests four repetitions were accomplished by genotype for each one of the potentials. The seeds of each repetition were involved in papers Germitest humidified with NaCl solution corresponding to the potential. The repetitions of both tests were maintained in a germinator with saturated humidity. The analysis were initiate four days after the induction of the saline stress. The evaluations of the first three variables analyzed were accomplished daily; the seeds were remove and counted when its germinated. For the length tests just the repetitions corresponding to the potential of NaCl 0,0 MPa were analysis 4 days after the beginning of the induction of the saline stress. The analysis of the repetitions of the potentials -0,2 and -0,4 and of the potentials -0,6, -0,8 and -1,0 MPa they were accomplished with 12 and 20 days, respectively. For accomplishment of the analisis of this test the shoot of the 20 plantules of each repetition was separate from the radicle and both parts were measured. The statistical analyses were performed using the GENMOD and GLM procedures of the SAS. For the variable germination, the cultivates CNPA 187 8H and BRS Safira stood out for the potential -0.8 MPa, with averages of 89% and 81%, respectively. The test of speed germination index to cultivate BRS Safira presented the largest averages for the two higher saline potentials. It was observed that the increase of the saline potential reduces the germination percentage and speed germination index. For each day of evaluation it was verified that the increase of the saline potential causes a reduction of the length both of the shoot and of the radicle. The radicle tends to grow more than the shoot until the potential -0,4 MPa

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Aiming identification of the components most affected by corrosion under saline environment conditions, we have carried out X-ray diffraction measurements in ceramic and bond materials, all in the powder form. The ceramic is analyzed before and after thermal annealing at 1000 degrees C, showing the same DRX peaks, although better defined after annealing. Identification suggests the presence of Al(6)Si(2)O(13) (Mullite) and SiO(2) (Quartz). Analysis of the junction (bond) material shows similar peaks, but a metallic preponderance is observed. Thermal annealing of the junction is done at much lower temperature, because it melts in the range 135 degrees C-170 degrees C, when a whitish smoke begins to show up along with strong sulfur odor.

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Este experimento objetivou estudar o possível efeito antiarritmogênico da levomepromazina em cães anestesiados pelo sevoflurano e submetidos a doses crescentes de adrenalina. Para tal, foram empregados 21 animais adultos, machos e fêmeas, sem raça definida e considerados sadios. Os cães foram separados em dois grupos, sendo um de 11 (G1) e outro de 10 (G2) animais. O G1 recebeu, por via intravenosa, solução salina a 0,9%, na dose de 0,2ml/kg (placebo), seguida 15 minutos após, pela aplicação de tiopental, pela mesma via, na dose suficiente para abolir o reflexo laringotraqueal. Procedeu-se à intubação orotraqueal e iniciou-se a administração de sevoflurano a 2,5V%, em circuito anestésico semi-fechado. Decorridos 20 minutos da indução anestésica, iniciou-se a administração contínua, por via intravenosa, com emprego de bomba de infusão, de solução de adrenalina a 2%, em doses crescentes de 1, 2, 3, 4 e 5m g/kg/min (M1 a M5, respectivamente), com incremento da dose a intervalos de 10 minutos. Para o G2, empregou-se a mesma metodologia substituindo-se o placebo por levomepromazina, na dose de 1mg/kg. Foi tomado o traçado eletrocardiográfico, na derivação D2, a partir da indução da anestesia. Para efeito estatístico, foi considerado o número total de batimentos cardíacos de origem não sinusal, coincidentes com cada dose de adrenalina. Os dados numéricos foram submetidos à Análise de Perfil, quando foi possível constatar que as médias do G1 foram crescentes de M1 a M3, diminuindo a partir deste último, até M5. No G2, foi encontrada arritmia ventricular sustentada apenas em M5. Os achados permitiram concluir que a levomepromazina minimiza a arritmia ventricular sustentada, induzida pela adrenalina em cães anestesiados pelo sevoflurano.

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The caffeine is a mild psychostimulant that has positive cognitive effects at low doses, while promotes detrimental effects on these processes at higher doses. The episodic-like memory can be evaluated in rodents through hippocampus-dependent tasks. The dentate gyrus is a hippocampal subregion in which neurogenesis occurs in adults, and it is believed that this process is related to the function of patterns separation, such as the identification of spatial and temporal patterns when discriminating events. Furthermore, neurogenesis is influenced spatial and contextual learning tasks. Our goal was to evaluate the performance of male Wistar rats in episodic-like tasks after acute or chronic caffeine treatment (15mg/kg or 30mg/kg). Moreover, we assessed the chronic effect of the caffeine treatment, as well as the influence of the hippocampus-dependent learning tasks, on the survival of new-born neurons at the beginning of treatment. For this purpose, we used BrdU to label the new cells generated in the dentate gyrus. Regarding the acute treatment, we found that the saline group presented a tendency to have better spatial and temporal discrimination than caffeine groups. The chronic caffeine group 15 mg/kg (low dose) showed the best discrimination of the temporal aspect of episodic-like memory, whereas the chronic caffeine group 30mg/kg (high dose) was able to discriminate temporal order, only in a condition of greater difficulty. Assessment of neurogenesis using immunohistochemistry for evaluating survival of new-born neurons generated in the dentate gyrus revealed no difference among groups of chronic treatment. Thus, the positive mnemonic effects of the chronic caffeine treatment were not related to neuronal survival. However, another plastic mechanism could explain the positive mnemonic effect, given that there was no improvement in the acute caffeine groups

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Oral and facial bone defects can undertake appearance, psychosocial well-being and stomathognatic function of its patients. Over the yerars several strategies for bone defect regeneration have arised to treat these pathologies, among them the use of frozen and irradiated bone allograft. Manipulation of bone grafts it s not determined yet, and several osteotomy alternatives can be observed. The present work evaluated with a microscope the bone fragments obtained from different osteotomy methods and irrigation on rings and blocks allografts irradiated and frozen at 80° negative in a rabbit model. The study is experimental in vitro and it sample was an adult male New Zealand rabbit. The animal was sacrificed to obtain long bones, that were submitted to freezing at 80º negative and irradiated with Cobalt- 60. Then the long bones were sectioned into 24 bone pieces, divided into 4 groups: G1 (n=06) osteotomy was performed with bur No. 6 forming rings with 5 mm thickness with high-speed handpiece with manual irrigation; G2 (n=06) osteotomy was performed with bur No. 6 forming rings with 5 mm thick with surgical motor with a manual irrigation rotation 1500 rpm; GA (n=06), osteotomy with trephine using manual irrigation with saline; and GB (n=06), osteotomy with trephine using saline from peristaltic pumps of surgical motor. Five bone pieces of each group were prepared for analysis on light microscopy (LM) and one on electronic scan electronic microscopy (SEM). On the SEM analysis edges surface, presence of microcracks and Smear Layer were evaluated. Analyzing osteotomy technics on SEM was observed: increased presence of microcracks cutting with high speed; increased presence of areas covered by Smear Layer when cutting with motor implant. The irrigation analysis with SEM was observed: that the presence of microcracks does not depend on the type of irrigation; on manual irrigation, there was greater discrepancy between the cutting lines. The descriptive analysis of the osteotomy and irrigation process on LM showed: histological analysis showing the bony margins with clear tissue changed layer, composed of blackened tissue of charred appearance near to the cortical bone; on the edges of the bony part, bone fragments that were displaced during the bone cut and bone irregularities were observed. After analysis of results we can conclude: that there was greater regularity of the bone cut using high-speed handpiece than using motor implant; the cut with trephine using saline irrigated from peristaltic pumps of surgical motor showed greater homogeneity when compared with manual irrigation; charred tissue was found in all obtained bone samples, whit no significant statistically difference on the proportion of carbonization of the two analysed technics

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Episodic memory refers to the recollection of what, where and when a specific event occurred. Hippocampus is a key structure in this type of memory. Computational models suggest that the dentate gyrus (DG) and the CA3 hippocampal subregions are involved in pattern separation and the rapid acquisition of episodic memories, while CA1 is involved in memory consolidation. However there are few studies with animal models that access simultaneously the aspects ‗what-where-when . Recently, an object recognition episodic-like memory task in rodents was proposed. This task consists of two sample trials and a test phase. In sample trial one, the rat is exposed to four copies of an object. In sample trial two, one hour later, the rat is exposed to four copies of a different object. In the test phase, 1 h later, two copies of each of the objects previously used are presented. One copy of the object used in sample trial one is located in a different place, and therefore it is expected to be the most explored object.However, the short retention delay of the task narrows its applications. This study verifies if this task can be evoked after 24h and whether the pharmacological inactivation of the DG/CA3 and CA1 subregions could differentially impair the acquisition of the task described. Validation of the task with a longer interval (24h) was accomplished (animals showed spatiotemporal object discrimination and scopolamine (1 mg/kg, ip) injected pos-training impaired performance). Afterwards, the GABA agonist muscimol, (0,250 μg/μl; volume = 0,5 μl) or saline were injected in the hippocampal subregions fifteen minutes before training. Pre-training inactivation of the DG/CA3 subregions impaired the spatial discrimination of the objects (‗where ), while the temporal discrimination (‗when ) was preserved. Rats treated with muscimol in the CA1 subregion explored all the objects equally well, irrespective of place or presentation time. Our results corroborate the computational models that postulate a role for DG/CA3 in spatial pattern separation, and a role for CA1 in the consolidation process of different mnemonic episodes

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In the behavioral paradigm of discriminative avoidance task, both short and long-term memories have been extensively investigated with behavioral and pharmacological approaches. The aim of the present study was to evaluate, using the abovementioned model, the hippocampal expression of zif-268 - a calcium-dependent immediate early gene involved with synaptic plasticity process - throughout several steps of memory formation, such as acquisition, evocation and extiction. The behavioral apparatus consisted of a modified elevaated plus-maze, with their enclosed arms disposed in "L". A pre-exposure to the maze was made with the animal using all arms enclosed, for 30 minutes, followed by training and test, during 10 minutes each. The between sections interval was 24h. During training, aversive stimuli (bright light and loud noise) were actived whenever the animals entered one of the enclosed armas (aversive arm). Memory acquisiton, retention and extinction were evaluated by the percentage of the total time spent exploring the aversive arm. The parameters evaluated (time spent in the arms and total distance traveled) were estimated with an animal tracking software (Anymaze, Stoelting, USA). Learning during training was estimated by the decrease of the time spent exploring the aversive arm. One hour after the beginning of each section, animals were anaesthetized with sodium-thiopental (i.p.) and perfused with 0.9% heparinized saline solution followed by 4% paraformaldehyde. Brains were cryoprotected with 20% sucrose, separeted in three blocks and frozen. The middle block, containing the hippocampus, was sectioned at 20 micro meters in the coronal plane and the resutant sections were submitted to zif-268 immunohistochemistry. Our results show an increased expression of zif-268 in the dentate gyrus (DG) during the evocation and extinction stages. There is a distinct participation of the DG during the memory evocation, but not during its acquisition. Inaddition, all hippocampal regions (CA1, CA3 and DG) presented an increased zif-268 expression during the process of extinction.

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Immediate-early genes (IEGs) expression has been widely used as a valuable tool to investigate brain areas activated by specific stimuli. Studies of natural vocalizations, specially in songbirds, have largely benefited from this tool. Here we used IEGs expression to investigate brain areas activated by the hearing of conspecific common marmoset (Callithrix jacchus) vocalizations and/or utterance of antiphonal vocalizations. Nine adult male common marmosets were housed in sound-attenuating cages. Six animals were stimulated with playbacks of freely recorded natural long distance vocalizations (phee calls and twitters; 45 min. total duration). Three of them vocalized in response (O/V group) and three did not (O/n group). The control group (C) was composed by the remaining animals, which neither heard the playbacks nor spontaneously vocalized. After one hour of the stimulation onset (or no stimulation, in the case of the C group), animals were perfused with 0,9% phosphate-saline buffer and 4% paraformaldehyde. The tissue was coronally sectioned at 20 micro meter in a cryostat and submitted to immunohistochemistry for the IEGs egr-1 and c-fos. Marked immunoreactivity was observed in the auditory cortex of O/V and O/n subjects and in the anterior cingulate cortex, the dorsomedial prefrontal cortex and the ventrolateral prefrontal cortex of O/V subjects. In this study, brain areas activated by vocalizations of common marmosets were investigated using IEGs expression for the first time. Our results with the egr-1 gene indicate that potential plastic phenomena occur in areas related to hearing and uttering conspecific vocalizations.

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GABAergic neurotransmission has been implicated in many aspects of learning and memory, as well as mood and anxiety disorders. The amygdala has been one of the major focuses in this area, given its essential role in modulating emotionally relevant memories. However, studies with male subjects are still predominant in the field. Here we investigated the consequences for an aversive memory of enhancing or decreasing GABAergic transmission in the basolateral nucleus of the amygdala (BLA). Wistar female rats were trained in the plus-maze discriminative avoidance task, in which they had to learn to avoid one of the enclosed arms where an aversive stimulus consisting of a bright light and a loud noise was given (day 1). Fifteen minutes before the test session (day 2) animals received 0,2 μL infusions of either saline solution, the GABAergic agonist muscimol (0,05 mg/ml), or the GABAergic antagonist bicuculine (0,025 mg/ml) bilaterally intra-BLA. On the test day, females in proestrous or estrous presented adequate retrieval and did not extinguish the task, while females in metestrous or diestrous presented impaired retrieval. In the first group, muscimol infusion impaired retrieval and bicuculline had no effect, suggesting naturally low levels of GABAergic transmission in the BLA of proestrous and estrous females. In the second group, muscimol infusion had no effect and bicuculline reversed retrieval impairment, suggesting naturally high levels of GABAergic transmission in the BLA of metestrous and diestous females. Additionally, proestrous and estrous females presented higher anxiety levels compared to metestrous and diestrous females, which could explain better performance of this group. On the other hand, BLA GABAergic system did not interfere with the innate fear response because drug infusions had no effect in anxiety. Thus, retrieval alterations caused by the GABAergic drugs were probably related specifically to memory processes

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The 2024 and 7050 aluminium alloys used as aircraft components were subjected to laboratory corrosion tests in sodium chloride solution, Light-microscope examinations make it possible to characterise morphological aspects of the localised corrosion. Image analysis was used to determine both depth and width of pits over corroded surfaces. It has been concluded that the annealing could reduce the pit growth in both alloys, by means of grains recrystallization or recovery. The 2024 alloy also tends to present an exfoliation mechanism, mainly throughout non-recrystallized and recrystallized grain boundaries, increasing the width and sustaining the depth of pit cavities during exposition to saline atmosphere. SEM and EDS analysis reveal the morphology and elemental distribution of the corrosion products formed after immersion corrosion test. Some of these products were identified by X-ray diffraction analysis. For 2024, Al(OH)(3), MS(OH)(2) and Cu2O were found. AI(OH)(3) and Cu2O were also found in 7050 samples.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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An interesting development in surfactants science and technology is their application as corrosion inhibitors, since they act as protective films over anodic and cathodic surfaces. This work aims to investigate the efficiency of saponified coconut oil (SCO) as corrosion inhibitor and of microemulsified system (SCO + butanol + kerosene oil + distilled water), in saline medium, using an adapted instrumented cell, via techniques involving linear polarization resistance (LPR) and mass loss coupons (MLC). For this, curves of efficiency versus SCO concentration (ranging between 0 and 75 ppm) have been constructed. According to the obtained results, the following efficiency levels were reached with OCS: 98% at a 75 ppm concentration via the LPR method and 95% at 75 ppm via the MLC method. The microemulsified system, for a concentration of 15 ppm of SCO, obtained maximum inhibition of 97% (LPR) and 93% (MLC). These data indicate that it is possible to optimize the use of SCO in similar applications. Previous works have demonstrated that maximal efficiencies below 90% are attained, typically 65% as free molecules and 77% in microemulsified medium, via the LPR method in a different type of cell. Therefore, it can be concluded that the adapted instrumented cell (in those used methods) showed to be an important tool in this kind of study and the SCO was shown effective in the inhibition of the metal

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In this work thiosemicarbazones [4-N-cinnamoyl-thiosemicarbazone (CTSC), 4-N-(2'-methoxycinnamoyl)-thiosemicarbazone (MCTSC), and 4-N-(4'-hydroxy-3'-methoxybenzoyl)-thiosemicarbazone (HMBTSC)] were solubilized in an microemulsion system (ME_OCS) which is rich in aqueous phase (O/W system). The system ME_OCS was obtained with saponified coconut oil (OCS) as (surfactant), butanol (cosurfactant), and kerosene as oil phase (Fo), using 40% of C/T (cosurfactant/surfactant), 5% of Fo and 55% of aqueous phase. The microemulsions systems CTSC_ME_OCS, MCTSC_ME_OCS and HMBTSC_ME_OCS effectiveness on a AISI 1020 carbon steel corrosion inhibition process were evaluated in a saline solution (NaCl 0.5%), using a galavostatic method. The tested thiosemicarbazones (TSC) showed highest inhibitors effects (85.7% for CTSC_ME_OCS, 84.0% for MCTSC_ME_OCS, and 83.3% HMBTSC_ME_OCS) at lower concentrations [0.19% of CTSC, 0.07% (MCTSC), and 0.26% (HMBTSC)]. Comparatively, the surfactant OCS (solubilized in H2O) as well as the system ME_OCS showed lower efficacy [71% for OCS (at 0.20 - 0.25% of concentration) and 74% for ME_OCS (at 0.5% of concentration)]. Since the microemulsion systems ME_OCS showed satisfactory interfacial adsorption, the greatest inhibitory effect of those TSC_ME_OCS systems could be correlated to both chemical composition of each tested TSC (which is rich in heteroatoms and aromatic ring) and also the presence of the surfactant OCS

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This study is an environmental diagnosis of the Jundiaí-Potengi/RN estuarine system waters, using calculations of pollution indicator indices such as the Water Quality Index (WQI) and the Toxicity Index (TI). The samples were collected at twelve points on the estuary, at high and low tide, between August and November 2007, over four campaigns. The study area, located in a high impact region, has various activities on its banks such as: discharge of untreated or undertreated domestic and industrial sewage, shrimp farming, immunizer stabilization lakes, riverside communities, etc. All the parameters analyzed were compared to the limits of CONAMA Resolution No. 357 of 2005 for healthy and saline Class 1 waters. The results found prove the impact caused by various activities, mainly the parameters related to the presence of organic material, such as DQO, DBO, COT and thermotolerant colliforms. The IQA for most of the collection points was of medium quality. For the metals, although values above the Resolution limits were found, most of them were lower than the detection limits of ICP-OES used, indicating that they tend to be transported by the dynamic of the tides or rainfall and are deposited in bottom sediments, resulting in a TI of 1.0 in this water, when they are absent, which occurs in most cases, or 0.0, when heavy metals are found in these waters