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The balance between precipitation and evapotranspiration (ET) has direct effect on vegetation, and any change in its structure and composition can influence it. The aim of this study is to determine experimentally the daily evapotranspiration (ET) of the invasive species, Hedychium coronarium, and to compare with a group of four native species of the riparian forest. The experiment was carried out in a greenhouse with three different treatments: (1) only the invasive species; (2) only native species; and (3) a mixture of invasive and native species. In each lysimeter, pressure transducers recorded the water level at every 15 min along 14 months. Daily ET was calculated by the method of Gribovszki et al. (2008) and varied according to the treatment, indicating that different species (invasive or native) use the water differently. The maximum accumulated daily ET occurred for mixture treatment (2540.16 mm), while the treatment with the invasive plant presented the lowest value (2172.53 mm). H. coronarium, in monodominant stands, can reduce evapotranspiration on invaded areas and increase it when immersed in the riparian forest.
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The alveolar bone is an important mineralized structure of the periodontal support apparatus, and information about the methylmercury (MeHg) effects on the structural integrity is scarce. Therefore, this study aimed to investigate whether systemic, chronic, and low-dose exposure to MeHg can change the alveolar bone microstructure of rats. Adult Wistar rats (n = 30) were exposed to 0.04 mg/kg/day of MeHg or vehicle through intragastric gavage. The animals were euthanized after 60 days, and blood samples were collected for trolox equivalent antioxidant capacity (TEAC), glutathione (GSH), lipid peroxidation (LPO), and comet assays. The mandible of each animal was collected and separated into hemimandibles that were used to determine the total Hg level in the bone and to analyze microstructural damage and alveolar bone loss in terms of trabecular number (Tb.N), trabecular thickness (Tb.Th), bone volume fraction (BV/TV), and exposed root area of the second molars. MeHg exposure triggered oxidative stress in blood represented by lower levels of GSH and TEAC and the increase in LPO and DNA damage of the blood cells. High total Hg levels were found in the alveolar bone, and the microstructural analyses showed a reduction in Tb.N, Tb.Th, and BV/TV, which resulted in an increase in the exposed root area and a decrease in bone height. Long-term MeHg exposure promotes a systemic redox imbalance associated with microstructural changes and alveolar bone loss and may indicate a potential risk indicator for periodontal diseases.
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Perda do Osso Alveolar , Compostos de Metilmercúrio , Perda do Osso Alveolar/induzido quimicamente , Perda do Osso Alveolar/diagnóstico por imagem , Animais , Mandíbula/diagnóstico por imagem , Compostos de Metilmercúrio/toxicidade , Estresse Oxidativo , Ratos , Ratos WistarRESUMO
INTRODUCTION: The aim of the present study was to compare the cyclic fatigue resistance of Reciproc R25 (R25) and Reciproc Blue R25 (R25B) instruments, after simulated clinical use in traditional (TradAC) and ultraconservative (UltraAC) endodontic access cavities. METHODS: Forty mandibular molars were randomly assigned into the following groups, according to the type of access and instrument to be used: TradAC and R25, TradAC and R25B, UltraAC and R25, and UltraAC and R25B. Teeth were accessed accordingly, and the root canals were prepared using "RECIPROC ALL" kinematics. The cyclic fatigue resistance of the forty used instruments was obtained measuring the time to fracture in an artificial stainless-steel canal. Ten brand new R25 and R25B were used as control groups. The fracture surfaces and the side cutting edges of the instruments were examined with a scanning electron microscope. Data were statistically analyzed using one-way ANOVA and post hoc Tukey tests with a significance level of P < 0.05. RESULTS: R25B instruments showed significantly higher cyclic fatigue resistance than R25, regardless of the access cavity type (P < 0.05). No differences were observed in the cyclic fatigue resistance between instruments without simulated clinical use and used in TradAC (P > 0.05). R25 and R25B used in UltraAC showed significantly lower cyclic fatigue resistance compared with the instruments used in TradAC and without simulated clinical use (P < 0.05). CONCLUSIONS: R25B files showed improved cyclic fatigue resistance than R25. The use of R25B and R25 files in mandibular molars with UltraACs decreased their cyclic fatigue resistance, compared with TradAC. CLINICAL RELEVANCE: The use of Reciproc and Reciproc Blue files in mandibular molars with ultra-conservative endodontic access cavities reduced their cyclic fatigue resistance. Clinicians should be aware about the reduced cyclic fatigue resistance of these files when used in mandibular molars with UltraAC, due to the synergistic effect of access angulation and severe curvature induced in the endodontic files.
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Instrumentos Odontológicos , Preparo de Canal Radicular , Desenho de Equipamento , Falha de Equipamento , Teste de Materiais , Aço Inoxidável , TitânioRESUMO
Nerium oleander Linn. is an Apocynaceae shrub which is among the most toxic ornamental plants. Although seizures are one of the symptoms associated with N. Oleander poisoning in humans, only a few studies are available on the behavioural and electrophysiological alterations caused by this plant poisoning. This study aimed at providing a thorough description of the electroencephalographic (EEG) and electromyographic (EMG) profiles throughout the experimental poisoning of Wistar rats (200-250â¯g) using ethanolic extract of N. oleander (EENO). Further, seizure control was assessed using different anticonvulsants. Male Wistar rat's behaviour was assessed upon EENO (150â¯mg/kg) administration and the animals were evaluated for muscle and neural activities through EMG and EEG recordings, respectively. The behavioural test showed two distinct phases of CNS activity: Phase I - myorelaxation and depression, and Phase II - excitability (agitated behaviour and seizures). Such phases were consistent with the EEG and EMG tracing patterns attained. Within the first 400â¯s of the recordings, during Phase I, the EMG showed no tracing amplitude variation. Later, the tracing pattern was changed and an intensification of the muscle contraction power in higher frequencies was observed during Phase II. The EEG showed initially a slight flattening in the tracings with a reduction in the intensity of the signal as per spectrogram of frequency attained. Thereafter, during Phase II, much higher amplitude tracings could be noted with an intensification of the signal, compatible with seizures. Seizure control was evaluated using four agents: phenytoin, phenobarbital, diazepam and scopolamine (at 10â¯mg/kg in all cases). While scopolamine was not effective in the seizure control, diazepam was the most efficient drug for the attenuation of the poisoning. Our results indicate the possibility of including phenytoin, phenobarbital and diazepam, mainly the latter, in the poisoning therapeutic protocol, including for those individuals who could be more susceptible to the poisoning by Nerium oleander as in the case of epileptic patients.
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Anticonvulsivantes/administração & dosagem , Comportamento Animal/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Encéfalo/fisiopatologia , Músculo Masseter/efeitos dos fármacos , Músculo Masseter/fisiopatologia , Nerium , Extratos Vegetais/toxicidade , Animais , Eletroencefalografia , Eletromiografia , Masculino , Intoxicação por Plantas/fisiopatologia , Ratos Wistar , Convulsões/prevenção & controleRESUMO
This work aimed to optimize an aqueous extract rich in phenolic compounds and potential functional properties made of Ilex paraguariensis, Melissa officinalis, and Cymbopogon citratus. The lyophilized extract was used for the development of an ice cream. Total phenolics, FRAP, DPPH, Folin-Ciocalteu's reducing capacity, and total reducing capacity of different combinations of herbal extracts were tested and modeled using response surface methodology. Simultaneous optimisation was employed to maximize the bioactive compounds in the extract and the lyophilized optimum combination was added to ice cream. The lyophilized extract contained quercetin-3-rutinoside, hesperidin, isoquercetin, caffeic acid, and 5,7-dihydroxyflavone. The optimised extract, which showed antihypertensive, antidiabetic, and antioxidant activity using in vitro protocols, increased total phenolics and antioxidant activity in comparison to the control ice cream. The ice cream presented a sensory acceptance index of 83%. After 72â¯days of storage (-18⯰C), total phenolics and antioxidant activity significantly decreased.
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Indústria de Processamento de Alimentos/métodos , Sorvetes , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Adolescente , Adulto , Anti-Infecciosos/farmacologia , Anti-Hipertensivos/química , Anti-Hipertensivos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Linhagem Celular , Cymbopogon/química , Feminino , Flavonoides/análise , Flavonoides/química , Armazenamento de Alimentos , Humanos , Sorvetes/análise , Ilex paraguariensis/química , Masculino , Melissa/química , Pessoa de Meia-Idade , Oligossacarídeos/química , Fenóis/química , PaladarRESUMO
Mercury (Hg) is a highly toxic metal, which can be found in its inorganic form in the environment. This form presents lower liposolubility and lower absorption in the body. In order to elucidate the possible toxicity of inorganic Hg in the hippocampus, we investigated the potential of low doses of mercury chloride (HgCl2) to promote hippocampal dysfunction by employing a chronic exposure model. For this, 56 rats were exposed to HgCl2 (0.375 mg/kg/day) via the oral route for 45 days. After the exposure period, the animals were submitted to the cognitive test of fear memory. The hippocampus was collected for the measurement of total Hg levels, analysis of oxidative stress, and evaluation of cytotoxicity, apoptosis, and tissue injury. It was observed that chronic exposure to inorganic Hg promotes an increase in mercury levels in this region and damage to short- and long-term memory. Furthermore, we found that this exposure model provoked oxidative stress, which led to cytotoxicity and cell death by apoptosis, affecting astrocytes and neurons in the hippocampus. Our study demonstrated that inorganic Hg, even with its low liposolubility, is able to produce deleterious effects in the central nervous system, resulting in cognitive impairment and hippocampal damage when administered for a long time at low doses in rats.
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Apoptose/efeitos dos fármacos , Comportamento Animal/efeitos dos fármacos , Hipocampo/metabolismo , Cloreto de Mercúrio/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Animais , Antioxidantes/química , Antioxidantes/metabolismo , Astrócitos/citologia , Astrócitos/efeitos dos fármacos , Astrócitos/metabolismo , Peso Corporal/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Encéfalo/patologia , Hipocampo/química , Hipocampo/efeitos dos fármacos , Masculino , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/patologia , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismoRESUMO
This study aimed to optimise the experimental conditions of extraction of the phytochemical compounds and functional properties of Centaurea cyanus petals. The following parameters were determined: the chemical composition (LC-ESI-MS/MS), the effects of pH on the stability and antioxidant activity of anthocyanins, the inhibition of lipid peroxidation, antioxidant activity, anti-hemolytic activity, antimicrobial, anti-hypertensive, and cytotoxic/cytoprotective effect, and the measurements of intracellular reactive oxygen species. Results showed that the temperature and time influenced (pâ¯≤â¯0.05) the content of flavonoids, anthocyanins, and FRAP. Only the temperature influenced the total phenolic content, non-anthocyanin flavonoids, and antioxidant activity (DPPH). The statistical approach made it possible to obtain the optimised experimental extraction conditions to increase the level of bioactive compounds. Chlorogenic, caffeic, ferulic, and p-coumaric acids, isoquercitrin, and coumarin were identified as the major compounds in the optimised extract. The optimised extract presented anti-hemolytic and anti-hypertensive activity in vitro, in addition to showing stability and reversibility of anthocyanins and antioxidant activity with pH variation. The C. cyanus petals aqueous extract exhibited high IC50 and GI50 (>900⯵g/mL) values for all cell lines, meaning low cytotoxicity. Based on the stress oxidative assay, the extract exhibited pro-oxidant action (10-100⯵g/mL) but did not cause damage or cell death.
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Anti-Hipertensivos/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Antioxidantes/farmacologia , Centaurea/química , Flores/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Antocianinas/análise , Ácidos Cafeicos/análise , Linhagem Celular Tumoral , Ácido Clorogênico/análise , Cromatografia Líquida , Ácidos Cumáricos/análise , Cumarínicos/análise , Avaliação Pré-Clínica de Medicamentos , Hemólise/efeitos dos fármacos , Humanos , Concentração de Íons de Hidrogênio , Concentração Inibidora 50 , Peroxidação de Lipídeos/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Quercetina/análogos & derivados , Quercetina/análise , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem , Água/químicaRESUMO
Passive monitoring for detection of influenza A viruses (IAVs) in pigs has been carried out in Brazil since 2009, detecting mostly the A(H1N1)pdm09 influenza virus. Since then, outbreaks of acute respiratory disease suggestive of influenza A virus infection have been observed frequently in Brazilian pig herds. During a 2010-2011 influenza monitoring, a novel H1N2 influenza virus was detected in nursery pigs showing respiratory signs. The pathologic changes were cranioventral acute necrotizing bronchiolitis to subacute proliferative and purulent bronchointerstitial pneumonia. Lung tissue samples were positive for both influenza A virus and A(H1N1)pdm09 influenza virus based on RT-qPCR of the matrix gene. Two IAVs were isolated in SPF chicken eggs. HI analysis of both swine H1N2 influenza viruses showed reactivity to the H1δ cluster. DNA sequencing was performed for all eight viral gene segments of two virus isolates. According to the phylogenetic analysis, the HA and NA genes clustered with influenza viruses of the human lineage (H1-δ cluster, N2), whereas the six internal gene segments clustered with the A(H1N1)pdm09 group. This is the first report of a reassortant human-like H1N2 influenza virus derived from pandemic H1N1 virus causing an outbreak of respiratory disease in pigs in Brazil. The emergence of a reassortant IAV demands the close monitoring of pigs through the full-genome sequencing of virus isolates in order to enhance genetic information about IAVs circulating in pigs.
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Surtos de Doenças/veterinária , Vírus da Influenza A Subtipo H1N2/isolamento & purificação , Infecções por Orthomyxoviridae/veterinária , Infecções Respiratórias/veterinária , Doenças dos Suínos/virologia , Animais , Brasil/epidemiologia , Vírus da Influenza A Subtipo H1N2/classificação , Infecções por Orthomyxoviridae/epidemiologia , Infecções por Orthomyxoviridae/virologia , Infecções Respiratórias/epidemiologia , Infecções Respiratórias/virologia , Suínos , Doenças dos Suínos/epidemiologiaRESUMO
Atresia of the foramina of Magendie and Luschka is a rare cause of obstructive hydrocephalus. Although this condition has been classically treated by CSF shunting, recent treatments have also included endoscopic third ventriculostomy. In the present study, the authors present the case of a patient with hydrocephalus in whom an alternative method was used following a CSF shunt malfunction. A young female patient in whom a shunt was placed during the patient's 1st year of life was faring well until she was 8 years old. She was admitted to the emergency department 5 times with signs of CSF shunt malfunction. Each time, the CT scan showed a slight dilation of the lateral and third ventricles and a large increase in the size of the fourth ventricle. In comparison, ventricles were smaller in a previous imaging study obtained when the patient was asymptomatic. Magnetic resonance imaging showed the same slight dilation of all the ventricles and a significant increase in the fourth ventricle. There was no aqueductal stenosis. An important enlargement of both lateral recesses of the fourth ventricle suggested the possibility of an atresia of the foramina. The foramen of Monro and the width of the third ventricle would not allow the passage of an endoscope. The decision was made to open those foramina endoscopically through the fourth ventricle. After induction of general anesthesia, with the patient in the prone position, a bur hole was made in the left paramedian and suboccipital region. The endoscope was introduced underneath the cerebellar hemisphere. The authors were then able to distinguish the floor of the fourth ventricle and other anatomical landmarks. Navigation through the lateral recesses allowed them to see the fine membranes closing the foramina. These membranes were opened with a monopolar cautery as a blunt instrument. The orifice was then enlarged with a 3 Fr Fogarty catheter. The authors also opened a bulging thin membrane located at the foramen of Magendie. During the postoperative period, the authors observed a marked improvement in the state of the patient's alertness as well as a disappearance of her headaches and cessation of vomiting. In addition, the patient's gait ataxia improved slowly. Six-month postoperative MR imaging demonstrated an unequivocal reduction in the size of the fourth ventricle. The patient was still doing well 36 months after the surgery. Endoscopic fourth ventriculostomy, the opening of the 3 foramina of the fourth ventricle, may be an alternative treatment in cases in which these structures are congenitally closed.