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1.
Braz. j. biol ; 83: e243245, 2023. tab, graf
Article in English | MEDLINE, LILACS, VETINDEX | ID: biblio-1278547

ABSTRACT

Abstract Although richness and distribution of woody species in the Cerrado physiognomies have been extensively studied, the shifts of woody species from savanna physiognomies to dry forests have not yet been addressed. Here, we investigate the effect of soil physical-chemical traits on the woody species turnover between adjacent cerrado stricto sensu and dry forest physiognomies. Woody species were surveyed, and soil and topographic variables measured, in 30 10×40 m plots systematically distributed, with 15 plots in each physiognomy. We found a spatially structured distribution of woody species, and differences of soil traits between cerrado stricto sensu and dry forest areas, mainly related to the aluminum saturation, base saturation, and available phosphorus. Aluminum saturation increased toward the savanna area, while base saturation increased toward the dry forest. Most woody species predominated in one physiognomy, such as Callisthene major in the cerrado stricto sensu and Anadenanthera colubrina in the dry forest. Only 20% of the species were widely distributed across both physiognomies or, not often, restricted to the intermediary values of the soil gradient. General results indicate that contrasting soil traits between cerrado stricto sensu and dry forest produce a strongly spatially organized and sharp transition in terms of species distribution between these physiognomies.


Resumo Embora a distribuição e a riqueza em espécies arbóreas nas fitofisionomias do Cerrado venham sendo bastante estudadas, a transição entre savanas e florestas deciduais ainda não foi abordada. Investigamos o efeito de características físico-químicas do solo sobre a distribuição de espécies arbóreas em região de contato entre cerrado sentido restrito e floresta estacional decidual (FED). As espécies arbóreas foram amostradas sistematicamente, e variáveis de topografia e características do solo foram medidas em 30 parcelas de 10×40 m, sendo 15 parcelas em cada fisionomia. A distribuição das espécies arbóreas foi espacialmente estruturada, e as características do solo diferiram entre as áreas de cerrado sentido restrito e FED, principalmente relacionadas à saturação de alumínio, saturação de bases e teores de fósforo. A saturação de alumínio aumentou em direção ao cerrado sentido restrito, enquanto a saturação de bases aumentou em direção à FED. A maioria das espécies arbóreas predominou em uma das fisionomias, como Callisthene major em cerrado sentido restrito e Anadenanthera colubrina em FED. Apenas 20% das espécies foram amplamente distribuídas em ambas as fisionomias ou, em poucos casos, restritas aos valores intermediários do gradiente de solo. Os resultados indicam um forte contraste de características do solo entre o cerrado sentido restrito e a FED, assim como uma transição acentuada e espacialmente organizada quanto à distribuição de espécies arbóreas.


Subject(s)
Soil , Grassland , Trees , Brazil , Forests
2.
Eng. sanit. ambient ; 27(1): 175-183, jan.-fev. 2022. tab, graf
Article in Portuguese | LILACS-Express | LILACS | ID: biblio-1364824

ABSTRACT

RESUMO Estudos de remoção de fósforo de efluentes por sorção em resíduos têm ganhado destaque na literatura. Entre estes resíduos, destaca-se o lodo de estação de tratamento de água rico em oxi-hidróxidos de alumínio e ferro. O presente estudo teve como objetivos remover, por sorção, fosfato de esgoto sanitário em reator de escoamento ascendente preenchido com lodo de estação de tratamento de água e comparar a cultura de milho submetida a diferentes fontes de fósforo: adubação convencional (Fonte 1); adubação convencional e lodo de estação de tratamento de água utilizado na sorção do fosfato (Fonte 2); e lodo de lodo de estação de tratamento de água utilizado na sorção do fosfato (Fonte 3). A remoção do fosfato, a partir do lodo de estação de tratamento de água, ocorreu nos três testes. No ensaio de sorção, após tempo de detenção hidráulica de 2,8 h, verificou-se remoção média de 96% de fosfato. Em relação ao aporte de fósforo por diferentes fontes, verificou-se que o emprego do lodo, nos tratamentos Fonte 2 e 3, aumentou o teor de matéria orgânica do solo e proporcionou maior tamponamento dele. Os teores foliares de macro e micronutrientes na cultura apresentaram valores satisfatórios, apesar da senescência de algumas plantas em Fonte 2 e 3. O reaproveitamento do lodo, nas doses aplicadas, foi suficiente para que o material vegetal analisado atingisse teores de chumbo consideráveis, o qual deve ser monitorado na utilização do resíduo no cultivo agrícola.


ABSTRACT Studies on the removal of phosphorus from effluents by sorption in residues have gained prominence in the literature. Among these residues, there is the sludge from a water treatment plant rich in oxyhydroxides of Aluminum and iron. The present study aimed to remove, by sorption, phosphate from sanitary sewage in upflow reactor filled with water treatment plant sludge, and to compare the corn crop subjected to different phosphorus sources: conventional fertilization (Source 1); conventional fertilization and water treatment plant sludge used in the sorption of phosphate (Source 2) and water treatment plant sludge used in the sorption of phosphate (Source 3). Removal of phosphate from the water treatment plant sludge occurred in all three tests. In the sorption assay, after 2.8 h hydraulic retention time, there was an average removal of 96% of phosphate. Regarding the contribution of phosphorus by different sources, it was found that the use of sludge, in treatments Source 2 and 3, increased the content of organic matter in the soil and provided greater buffering. The leaf contents of macro and micronutrients in the crop showed satisfactory values, despite the senescence of some plants in Source 2 and 3. The reuse of the sludge, in the applied doses, was enough for the analyzed plant material to reach considerable lead contents, which must be monitored when using the residue in agricultural cultivation.

3.
Ciênc. rural (Online) ; 52(1): e20200293, 2022. graf
Article in English | LILACS-Express | LILACSEXPRESS, LILACS, VETINDEX | ID: biblio-1286037

ABSTRACT

ABSTRACT: The harvesting process is a current challenge for the commercial production of microalgae because the biomass is diluted in the culture medium. Several methods have been proposed to harvest microalgae cells, but there is not a consensus about the optimum method for such application. Herein, the methods based on sedimentation, flocculation, and centrifugation were evaluated on the recovery of Chlorella sorokiniana BR001 cultivated in a low-nitrogen medium. C. sorokiniana BR001 was cultivated using a low-nitrogen medium to trigger the accumulation of neutral lipids and neutral carbohydrates. The biomass of C. sorokiniana BR001 cultivated in a low-nitrogen medium showed a total lipid content of 1.9 times higher (23.8 ± 4.5%) when compared to the biomass produced in a high-nitrogen medium (12.3 ± 1.2%). In addition, the biomass of the BR001 strain cultivated in a low-nitrogen medium showed a high content of neutral carbohydrates (52.1 ± 1.5%). The natural sedimentation-based process was evaluated using a sedimentation column, and it was concluded that C. sorokiniana BR001 is a non-flocculent strain. Therefore, it was evaluated the effect of different concentrations of ferric sulfate (0.005 to 1 g L-1) or aluminum sulfate (0.025 to 0.83 g L-1) on the flocculation process of C. sorokiniana BR001, but high doses of flocculant agents were required for an efficient harvest of biomass. It was evaluated the centrifugation at low speed (300 to 3,000 g) as well, and it was possible to conclude that this process was the most adequate to harvest the non-flocculent strain C. sorokiniana BR001.


RESUMO: O processo de colheita é um desafio atual para a produção comercial de microalgas porque a biomassa é diluída no meio de cultivo. Diversos métodos têm sido propostos para coletar células de microalgas, porém não existe um consenso sobre um método ótimo para tal aplicação. Neste estudo, métodos baseados em sedimentação, floculação e centrifugação foram avaliados na recuperação de Chlorella sorokiniana BR001 cultivada em um meio com baixo teor de nitrogênio. C. sorokiniana BR001 foi cultivada em um meio com baixo teor de nitrogênio para induzir ao acúmulo de lipídeos e carboidratos neutros. A biomassa de C. sorokiniana BR001 cultivada em um meio com baixo teor de nitrogênio apresentou um teor de lipídeos 1,9 vezes superior (23,8 ± 4,5%), quando comparada à biomassa produzida em um meio com alto teor de nitrogênio (12,3 ± 1,2%). Adicionalmente, a biomassa da linhagem BR001 cultivada em um meio com baixo teor de nitrogênio apresentou alto teor de carboidratos neutros (52,1 ± 1,5%). O processo baseado em sedimentação natural foi avaliado utilizando uma coluna de sedimentação e concluiu-se que C. sorokiniana BR001 é uma linhagem não floculante. Portanto, o efeito de diferentes concentrações de sulfato férrico (0,005 a 1 g L-1) ou sulfato de alumínio (0,025 a 0,83 g L-1) foram avaliados no processo de floculação de C. sorokiniana BR001, mas altas doses de floculantes foram necessárias para uma colheita de biomassa eficiente. Também foi avaliada a centrifugação em baixa velocidade (300 a 3.000 g), e foi possível concluir que este processo constituiu o mais adequado para a colheita da linhagem não floculante C. sorokiniana BR001.

4.
Article in Chinese | WPRIM | ID: wpr-910392

ABSTRACT

Objective:To determine and optimize the radiation quality of the calibration system for mammography dosimeters in IAEA/WHO Secondary Standard Dosimetry Laboratory and to study the requirements for accuracy of thickness of the aluminum sheets used in the measurement, with a view to ensure the accuracy of the radiation quality.Methods:For the measurements of tube voltage and RQR-M radiation quality, a standard kV meter was used to determine the actual tube voltage value of the system under continuous exposure for 30 s by setting tube voltage of 25, 28, 30 and 35 kV, respectively, and aluminum sheet method was used to determine the first half value layer (HVL 1). The kV values were adjusted to make the reading of the standard kV meter as close as possible to its nominal value, so as to obtain the set kV value, actual tube voltage and HVL 1 per 1 kV within the nominal 25-35 kV range. For effects of different thickness of aluminum sheets on the result of HVL 1 measurement, a comparison was made between HVL 1 measured by aluminum sheet with thickness of 0.318 mm and 0.369 mm and HVL 1 measured under 18 different groups of aluminum sheet using a selected 30 kV tube voltage. Results:After the set kV values were adjusted, the actual tube voltage deviations from the nominal values under 25, 28, 30 and 35 kV were reduced from 0.55, 0.34, 0.33, 0.30 to 0.04, 0.02, -0.04, -0.01, and the HVL 1 deviations were reduced from 0.011, 0.007, 0.010, 0.012 to 0.000, 0.003, 0.003, 0.010, respectively. When the thickness differences between the two types of aluminum sheet and the reference HVL 1 were both within 0.1 mm, the deviations of the measured HVL 1 were all less than 0.01 mm Al, and the result was relatively accurate. However, when the differences exceeded that of 0.1 mm, most of the deviations of the measured HVL 1 were between 0.01 and 0.02 mm Al, and the measured result was not accurate. Conclusions:Although the RQR-M radiation quality of the calibration system was deviated, it is still within the range specified under the IEC 61267-2005. The radiation quality was closer to the standard values after fine-tuning the system tube voltage. In order to measure the HVL 1 more accurately, the thickness differences between the used aluminum sheet and nominal HVL 1 should not be greater than 0.1 mm Al.

5.
Article in Chinese | WPRIM | ID: wpr-886091

ABSTRACT

Objective To investigate aluminum content in commercially available flour products in Minhang District, Shanghai, and to assess the risk of dietary aluminum exposure among permanent residents in Minhang. Methods From 2018 to 2019, a total of 227 samples including fried flour products, steamed flour products, puffed products and baked flour products, were collected in Minhang District to detect the aluminum content. The food frequency table was used to investigate the consumption of flour foods by permanent residents in Minhang District and to assess population dietary aluminum exposure risk. Results The average content of aluminum in 227 kinds of flour products was 31.66 mg/kg, and the exceeding standard rate was 3.96%. The over-standard foods were all fried flour products, and the over-standard rate reached 10.47%. Moreover, the aluminum over standard rate of flour products produced by itinerant vendors and restaurants was significantly higher than that of flour products produced by supermarkets and manufacturers. The average dietary intake of aluminum in Minhang residents was 0.18 mg/kg per week, accounting for 9.03% of the provisional tolerable weekly intake (PTWI). The aluminum exposure of the population with high consumption of foods was 1.4 mg/kg per week, accounting for 69.90% of the PTWI. Among the four types of flour products, fried flour products had the highest contribution rate to aluminum exposure. The daily consumption of fried flour products in males was significantly higher than that in females (P<0.05), and the 18-34 age group was significantly higher than the 60 years old and above group (P<0.05). Conclusion The risk of the average dietary aluminum exposure of flour foods among Minhang residents is relatively low, but people with high consumption of foods would be confronted with increased health risks. It is necessary to strengthen the supervision on the use of aluminum-containing additives in itinerant vendors and restaurants, and actively advocate reducing the frequency and the consumption of fried flour products, thus reduce the exposure to the high risk of dietary aluminum in fried flour products

6.
Article in Chinese | WPRIM | ID: wpr-877345

ABSTRACT

Objective @#To explore the effects of two hemostatic agents on the bonding strength of different bonding systems in primary tooth dentin.@*Methods @# Seventy-two retained deciduous teeth were randomly selected. Forty-eight teeth were used to construct the microleakage model, the other 24 teeth were cut along the mesial and distal directions and 48 samples were obtained to construct the shear bond strength model. The two experiments were divided into 2 groups. Group A was the total-etch group: A1 (ViscoStat + Spectrum Bond NT); A2 (ViscoStat Clear + Spectrum Bond NT); and A3 (Non + Spectrum Bond NT); Group B was the self-etch group: B1 (ViscoStat + Single bond Universal Adhesive); B2 (ViscoStat Clear + Single bond Universal Adhesive); and B3 (Non + Single bond Universal Adhesive). Microleakage experiments and shear bond strength experiments were carried out respectively and the morphology of the fracture surface was observed by scanning electron microscopy.@* Results @#There was no significant difference in microleakage among groups A1, A2, and A3 (P > 0.05). There was no significant difference in microleakage among groups B1, B2, and B3 (P > 0.05). There was no significant difference in the shear bond strength among groups A1, A2 and A3 (P > 0.05). The shear bond strength of groups B1 and B2 was significantly lower than that of group B3 (P < 0.05). There was no significant difference between groups B1 and B2 (P > 0.05). @*Conclusion@#ViscoStat and ViscoStat Clear had no effect on the marginal integrity of deciduous tooth dentin under the different bonding systems. The two hemostatic agents reduced the shear bonding strength of deciduous tooth dentin under the self-etch adhesive system, but had no effect on the shear bonding strength of deciduous tooth dentin under the total-etch adhesive system.

7.
Article | IMSEAR | ID: sea-205654

ABSTRACT

Agricultural revolution and increasing pesticidal use have brought its share of downsides in the form of pesticidal poisoning. Every year approximately 300,000 deaths happen worldwide due to pesticide poisoning. Organophosphates, chlorates, and aluminum phosphide are the commonly used pesticides. Alkaline phosphatase (ALP) is the most lethal among the available pesticides and no antidote is available and aptly called as suicide poison. The common use and easy availability of ALP is causing acute and chronic health effects which have reached major proportions in Asian and Middle Eastern countries such as India, Bangladesh, Iran, Jordan, and Sri Lanka. Toxicity of ALP is related to prompt release of lethal phosphine gas as ALP tablet absorbs moisture. Phosphine gas mainly affects cardiovascular system gastrointestinal tracts, lungs, and kidneys. The clinical features of poisoning include nausea, vomiting, abdominal pain, pulmonary edema, cyanosis shock arrhythmias, and alter sensorium. Diagnosis of ALP poisoning largely depends on history and clinical setting and treatment is usually initiated without waiting for silver nitrate paper test or gastric aspirate analysis. Treatment includes early gastric lavage symptomatic supportive therapy and palliative care. There has been greater understanding about the mechanism and pathophysiology of ALP toxicity over the years, although that cannot be commented about the treatment modalities. Government efforts to restrict sale have been offset by the lack of strict enforcement by regulatory agencies. Case fatality rates from ALP poisoning have shown some decline over the years due to early supportive management. Different treatment modalities and protocols have been tried at various centers with variable success; however, further research for an antidote is the need of the hour.

8.
Biosci. j. (Online) ; 36(4): 1083-1089, 01-06-2020.
Article in English | LILACS | ID: biblio-1147207

ABSTRACT

Phosphorus is one of the most abundant chemical elements but has a low bioavailability index. Therefore, microrganisms play a fundamental role in providing insoluble phosphorus to plants. The objective of this study was to evaluate the capacity of bacteria to solubilize inorganic phosphates in soils with different fertilization histories. Soil and rhizosphere samples were collected from a Red Distroferric Latosol, including a control without mineral or organic fertilizer (C), treatment with mineral fertilizer (MF) according to the needs of each crop, and treatment with organic fertilizer [300 m3 ha-1 of swine wastewater (SW)]. The medium containing calcium phytate presented more colony-forming units (CFU) for all fertilization histories, and growth in treatments C and MF was 50% higher than treatment with SW. CFU values in soils treated with SW were lower than those in the other treatments, and the diversity of insoluble phosphate-solubilizing bacteria (PSB) was higher in treatment C. These results indicate a negative relationship between phosphorus concentrations and the number of PSB.


O fósforo é um dos elementos químicos mais abundantes, mas tem um baixo índice de biodisponibilidade. Portanto, micro-organismos desempenham um papel fundamental no fornecimento de fósforo insolúvel para as plantas. O objetivo deste trabalho é avaliar a capacidade das bactérias em solubilizar fosfatos inorgânicos em solos com diferentes históricos de fertilização. Amostras de solo e rizosfera foram coletadas de um Latossolo Vermelho Distroférrico, incluindo controle sem adubação mineral ou orgânica (C), tratamento com adubação mineral (MF) de acordo com as necessidades de cada cultura e tratamento com adubação orgânica [300 m3 ha-1 de águas residuárias da suinocultura (SW)]. O meio contendo fitato de cálcio apresentou mais unidades formadoras de colônias (UFC) para todas as histórias de fertilização, e o crescimento nos tratamentos C e MF foi 50% maior que o tratamento com SW. Os valores de CFU nos solos tratados com SW foram menores que nos demais tratamentos, e a diversidade de bactérias insolúveis solubilizadoras de fosfato (PSB) foi maior no tratamento C. Esses resultados indicam uma relação negativa entre as concentrações de fósforo e o número de PSB.


Subject(s)
Phosphorus , Plants , Soil , Bacteria
9.
J. bras. nefrol ; 42(2): 138-146, Apr.-June 2020. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1134824

ABSTRACT

ABSTRACT Introduction: Mineral and bone disorders (MBD) are major complications of chronic kidney disease (CKD)-related adverse outcomes. The Brazilian Registry of Bone Biopsy (REBRABO) is an electronic database that includes renal osteodystrophy (RO) data. We aimed to describe the epidemiological profile of RO in a sample of CKD-MBD Brazilian patients and understand its relationship with outcomes. Methods: Between August 2015 and March 2018, 260 CKD-MBD stage 3-5D patients who underwent bone biopsy were followed for 12 to 30 months. Clinical-demographic, laboratory, and histological data were analyzed. Bone fractures, hospitalizations, and death were considered the primary outcomes. Results: Osteitis fibrosa, mixed uremic osteodystrophy, adynamic bone disease, osteomalacia, osteoporosis, and aluminum (Al) accumulation were detected in 85, 43, 27, 10, 77, and 65 patients, respectively. The logistic regression showed that dialysis vintage was an independent predictor of osteoporosis (OR: 1.005; CI: 1.001-1.010; p = 0.01). The multivariate logistic regression revealed that hemodialysis treatment (OR: 11.24; CI: 1.227-100; p = 0.03), previous parathyroidectomy (OR: 4.97; CI: 1.422-17.241; p = 0.01), and female gender (OR: 2.88; CI: 1.080-7.679; p = 0.03) were independent predictors of Al accumulation; 115 patients were followed for 21 ± 5 months. There were 56 hospitalizations, 14 deaths, and 7 fractures during follow-up. The COX regression revealed that none of the variable related to the RO/turnover, mineralization and volume (TMV) classification was an independent predictor of the outcomes. Conclusion: Hospitalization or death was not influenced by the type of RO, Al accumulation, or TMV classification. An elevated prevalence of osteoporosis and Al accumulation was detected.


RESUMO Introdução: Os distúrbios minerais e ósseos (DMO) são importantes complicações da doença renal crônica (DRC) associadas à desfechos adversos. O Registro Brasileiro de Biópsia Óssea (REBRABO) é um banco de dados eletrônico que inclui dados sobre osteodistrofia renal (OR). Nosso objetivo foi descrever o perfil epidemiológico da OR em uma amostra de pacientes brasileiros com DMO-DRC e entender sua associação com os desfechos. Métodos: Entre agosto de 2015 e março de 2018, 260 pacientes com DMO-DRC estágio 3-5D submetidos à biópsia óssea foram acompanhados por 12 a 30 meses. Dados clínico-demográficos, laboratoriais e histológicos foram analisados. Fraturas ósseas, hospitalizações e óbito foram considerados como desfechos primários. Resultados: Osteíte fibrosa, osteodistrofia urêmica mista, doença óssea adinâmica, osteomalácia, osteoporose e acúmulo de alumínio (Al) foram detectados em 85, 43, 27, 10, 77 e 65 pacientes, respectivamente. A regressão logística mostrou que o tempo em diálise foi um preditor independente de osteoporose (OR: 1.005; IC: 1.001-1.010; p = 0,01). A regressão logística multivariada revelou que o tratamento hemodialítico (OR: 11,24; IC: 1,227-100; p = 0,03), paratireoidectomia prévia (OR: 4,97; IC: 1,422-17,241; p = 0,01) e sexo feminino (OR: 2,88; IC: 1,080-7,679; p = 0,03) foram preditores independentes de acúmulo de Al; 115 pacientes foram acompanhados por 21 ± 5 meses. Houve 56 internações, 14 óbitos e 7 fraturas durante o seguimento. A regressão COX revelou que nenhuma das variáveis relacionadas ao tipo de OR/remodelação-mineralização-volume (classificação TMV) foi um preditor independente de desfechos. Conclusão: A hospitalização ou óbito não foram influenciadas pelo tipo de OR, acúmulo de Al ou classificação de TMV. Foi detectada uma prevalência elevada de osteoporose e acúmulo de Al.

10.
Article | IMSEAR | ID: sea-209435

ABSTRACT

Introduction: Commonly used polymethyl methacrylate (PMMA) denture base material cannot be considered as ideal due toinferior thermal and mechanical properties.Aim: The aim of the study was to evaluate and compare the thermal conductivity, flexural strength, and surface hardness ofheat cure acrylic resin incorporated with 10 wt.% and 15 wt.% alumina and conventional denture base resin.Materials and Methods: A total of 108 specimens were prepared. Specimens were divided into three main groups. Group Aspecimens were disk shaped (50 mm × 5 mm) and used for measuring thermal conductivity. Groups B and C specimens wererectangular shaped (65 mm × 10 mm × 3 mm) and were used for measuring flexural strength and surface hardness, respectively.Each group was further divided into three subgroups (1, 2, and 3) depending on the concentration, namely, PMMA without filler(control), PMMA + 10 wt.% of Al2O3, and PMMA + 15 wt.% of Al2O3 containing 12 samples each. Thermal conductivity wasmeasured using a modified guarded hot plate apparatus. Flexural strength was assessed with a three-point bending test usinga universal testing machine. Hardness testing was conducted using a Vickers Hardness Tester. The results were analyzedusing one-way ANOVA followed by post hoc comparison by Tukey’s method.Results: Mean values of thermal conductivity were (in W/mK) 0.190, 0.231, and 0.275 for subgroups A1, A2, and A3, respectively.The mean flexural strength values were (in MPa) 56.62, 66.73, and 74.24 for subgroups B1, B2, and B3, respectively. Meanvalues of surface hardness was calculated to be (in HV) 15.17, 16.51, and 17.91 for subgroup C1, C2, and C3, respectively.There was statistically significant improvement in thermal conductivity, flexural strength, and surface hardness after incorporationof alumina and the increase was in proportion to the weight percentage of alumina filler.Conclusion: Incorporation of alumina into heat cure denture base resin significantly improved the thermal conductivity, flexuralstrength, and surface hardness.

11.
Article | IMSEAR | ID: sea-202837

ABSTRACT

Fixed partial dentures (FPDs) with high-strength all-ceramicsystems are necessary for replacing missing teeth. Widerange of materials and methods are available to fabricate arestoration outside the mouth and subsequently integratewith a tooth. The traditional methods of ceramic fabricationhave been described to be time-consuming, techniquesensitive, and rather unpredictable due to the many variablespresent which affect the outcome. All-ceramic restorations,has become a segment of dentistry which has experiencedtremendous improvements in the recent years. The increasinguse of polycrystalline alumina and zirconia as frameworkmaterials and the increasing popularity and variety ofcomputer-aided design and computer-aided manufacturing(CAD-CAM) systems seem to be mutually accelerating trendsover the last three decades. This article presents a review ofthe development of all-ceramic restorations, including theevolution and development of materials, technologies andhow to improve the strength of all-ceramic restorations, withrespect to survival, applications, strength, color, and aesthetics.The literature demonstrates that multiple all-ceramic materialsand systems that are currently available for clinical use andconcludes there is not a single universal material or, systemavailable to suit for all clinical situations.

12.
Arq. bras. med. vet. zootec. (Online) ; 72(1): 199-207, Jan.-Feb. 2020. tab, graf, ilus
Article in English | LILACS, VETINDEX | ID: biblio-1088910

ABSTRACT

The target cp1002_RS01850 from Corynebacterium pseudotuberculosis was used to construct a DNA and recombinant subunit vaccine against caseous lymphadenitis. Recombinant protein rCP01850 was expressed in Escherichia coli using pAE vector, and DNA vaccine was engineered with pTARGET vector. BALB/c mice were divided in five groups containing eight animals each, inoculated with: pTARGET/cp01850 as DNA vaccine (G1); rCP01850 plus Al (OH)3 as recombinant subunit vaccine (G2); pTARGET/cp01850 and a boost with rCP01850 plus Al (OH)3 (G3); pTARGET (G4); or Al (OH)3 (G5). Mice were inoculated and blood samples were collected on days 0, 21, and 42 for the analysis of total IgG, IgG1 and IgG2a by ELISA. In each group, five animals were challenged with Mic-6 C. pseudotuberculosis strain, and three were used for cytokine quantification by qPCR. Although no group has been protected by vaccines against lethal challenge, G2 showed an increase in the survival rate after challenge. Significantly higher levels of IL-4, IL-12, IFN-γ, total IgG, IgG1 and IgG2a were also detected for G2, evidencing a mixed Th1/Th2 immunological profile. In conclusion, despite no protection level provided by different vaccinal strategies using cp1002_RS01850 from C. pseudotuberculosis, G2 developed a Th1/Th2 immune response with an increase in survival rate.(AU)


O alvo cp1002_RS01850 de Corynebacterium pseudotuberculosis foi utilizado para construir uma vacina recombinante de subunidade e de DNA contra a linfadenite caseosa. A proteína recombinante rCP01850 foi expressa em Escherichia coli usando o vetor pAE, e a vacina de DNA foi construída com o vetor pTARGET. Camundongos BALB/c foram divididos em grupos de oito animais, inoculados com: pTARGET/cp01850 como vacina de DNA (G1); rCP01850 e Al (OH)3 como vacina recombinante de subunidade (G2); pTARGET/cp01850 e um boost com rCP01850 e Al (OH)3 (G3); pTARGET (G4); ou Al (OH)3 (G5). Os animais foram inoculados e amostras de sangue foram coletadas nos dias 0, 21, e 42 do experimento para a análise de IgG total, IgG1 e IgG2a por ELISA. De cada grupo, cinco animais foram desafiados com a cepa Mic-6 de C. pseudotuberculosis, e três foram usados para a quantificação de citocinas por qPCR. Apesar de nenhum grupo ter sido protegido pelas vacinas testadas contra o desafio letal, G2 apresentou taxa de sobrevida e níveis de IL-4, IL-12, IFN-γ, IgG total, IgG1 e IgG2a significativamente mais altos, evidenciando um perfil imunológico misto Th1/Th2. Conclui-se que apesar das diferentes estratégias vacinais utilizando cp1002_RS01850 de C. pseudotuberculosis não terem sido capazes de gerar proteção, G2 desenvolveu uma resposta Th1/Th2 e elevou a taxa de sobrevida.(AU)


Subject(s)
Animals , Mice , Acid Phosphatase , Immunization, Secondary/veterinary , Corynebacterium pseudotuberculosis , Lymphadenitis/immunology , Recombinant Proteins , Aluminum Hydroxide
13.
Int J Pharm Pharm Sci ; 2020 Jan; 12(1): 11-20
Article | IMSEAR | ID: sea-206053

ABSTRACT

Objective: The present study was designed to evaluate the effect of zinc oxide nanoparticles (ZnO NPs) on Aluminum chloride (AlCl3)-induced hepato-renal injury.  Methods: Animals were divided into, I-control group; rats received saline, II-AlCl3 group; animals received 100 mg AlCl3/kg body weight, III-ZnO NPs group; rats received 10 mg ZnO NPs/kg body weight, and IV group ZnO NPs+AlCl3. All rats were administered their respective doses daily for 6 w. Hepatorenal function parameters in sera; aminotransferases, bilirubin, urea, and creatinine were estimated. Lipid peroxide level and nitrite\nitrate ratio, glutathione content, glutathione peroxidase, glutathione reductase, catalase, superoxide dismutase activities and interleukin-1β, tumor necrosis factor-α levels were determined in both tissues. The histopathological and the immunohistochemical investigations of nuclear factor-kB expression were carried out.  Results: ZnO NPs treatment to AlCl3-intoxicated rats significantly reduced Al accumulation (at p<0.05) in the hepatorenal tissue and increased zinc accumulation (at p<0.05) in liver and kidney, respectively, with respect to AlCl3-group, thus inhibiting oxidative stress and inflammation parameters represented by lipid peroxidation and nitric oxide levels (at p<0.05) compared to AlCl3 group and elevated antioxidant parameters (at p<0.05), compared to AlCl3 treated group, while suppressed interleukin-1β, tumor necrosis factor-α levels (at p<0.05) and the nuclear factor-kB activation in liver and kidney, especially in the kidney if compared to AlCl3-treated group. Hepatorenal function indices indicated significant decreases compared to AlCl3 group (at p<0.05). Conclusion: Results indicated the ameliorative effect of ZnO NPs on aluminum-induced hepato-renal damage.

14.
China Occupational Medicine ; (6): 686-690, 2020.
Article in Chinese | WPRIM | ID: wpr-881954

ABSTRACT

OBJECTIVE: To explore the relationship between occupational aluminum exposure and fasting blood glucose level in workers. METHODS: A cluster sampling method was used to select 178 occupational aluminum-exposed workers as the exposure group, and 178 workers without occupational aluminum exposure as the control group in a large aluminum factory in Shanxi Province. Glucose oxidase method was used to measure the fasting blood glucose level, and inductively coupled plasma mass spectrometry was used to measure the plasma aluminum level in these workers. A generalized linear model was used to analyze the correlation between plasma aluminum exposure level and fasting blood glucose in these workers. RESULTS: The blood aluminum level of workers in the exposure group was higher than that of the control group [median: 39.58 vs 16.67 μg/L, P<0.01]. The fasting blood glucose level of workers in the exposure group was higher than that of the control group [(5.33±0.79) vs(5.15±0.41) mmol/L, P<0.01]. The results of the generalized linear model analysis showed that the blood aluminum level of workers was positively correlated with their fasting blood glucose level after adjusting for age, body mass index, smoking, drinking, exercise, family history of diabetes, and incidence of diabetes(P<0.05). There was a dose-response relationship between the blood aluminum level and fasting blood glucose level of workers in the groups of junior high school and below and high school(all P_(trend)<0.01). There was no correlation found between blood aluminum level and fasting blood glucose level in the group of college and above(P_(trend)>0.05). There was a dose-response relationship between the blood aluminum level and the fasting blood glucose level in the workers in the non-exercise group(P_(trend)<0.01). There was no correlation found between the blood aluminum level and the fasting blood glucose level in the exercise group(P_(trend)>0.05). CONCLUSION: The blood aluminum level of workers exposed to occupational aluminum is positively correlated with their fasting blood glucose level. Higher education level or exercise can moderately reduce the effect of blood aluminum level on fasting blood glucose.

15.
China Occupational Medicine ; (6): 424-427, 2020.
Article in Chinese | WPRIM | ID: wpr-881916

ABSTRACT

OBJECTIVE: To explore the effect of occupational aluminum exposure on the blood of male workers. METHODS: A total of 249 male workers were selected as the research subjects by cluster sampling method in the electrolytic workshop of an aluminum plant. Blood samples were collected for determination of the blood aluminum concentration and blood routine. The subjects were divided into low-, medium-, and high-aluminuml groups based on the tertile of blood aluminum level(P_(33) is 13.9 μg/L, P_(67) is 37.7 μg/L). RESULTS: The red blood cell(RBC) count and hemoglobin level in patients of the high-aluminum group were lower than that of the low-aluminum group(P<0.05). There was no significant difference of the RBC count and hemoglobin level of patients in middle-aluminum group compared with that of the low-and high-aluminum groups(P>0.05). There was no statistical significant difference in white blood cell count and platelet count among the three groups(P>0.05). The results of the generalized linear regression model showed that the higher the blood aluminum level, the lower the RBC count and hemoglobin level of workers(P<0.05) after eliminating confounding factors such as age, length of service, education level, smoking, and drinking. CONCLUSION: Occupational aluminum exposure can cause a decrease of RBC count and hemoglobin level with a dose-effect relationship in workers.

16.
China Occupational Medicine ; (6): 141-146, 2020.
Article in Chinese | WPRIM | ID: wpr-881876

ABSTRACT

OBJECTIVE: To study the effect of sub-chronic aluminum exposure on synaptic plasticity in the hippocampus of rats and to explore the mechanism of phosphatidylinositol 3 kinase(PI3 K)/protein kinase B(AKT)/rapamycin target protein(mTOR) signaling pathway. METHODS: Specific pathogen free adult healthy male SD rats were randomly divided into control group and low-, medium-and high-dose groups based on body weight, with 10 rats in each group. Rats were treated with maltol aluminum solution at the concentrations of 0, 10, 20 and 40 μmol/kg body weight by intraperitoneal injection, 5 days per week for 3 months. After the exposure, rats were weighed. Morris water maze was used to test the learning and memory ability, and the two-electrode binding technique was used to record the long-term potentiation(LTP) amplitude in the hippocampus CA1 area of rats. The protein expression of PI3 K, AKT and mTOR in rat hippocampus tissues was detected by Western blot. RESULTS: After the exposure, the body weights of rats in the medium-and high-dose groups were lower than that of the control group(P<0.05). The results of the positioning navigation experiment showed that the escape latencies of the rats in the medium-and high-dose groups were shorter than that in the control group during the 2 nd to 4 th days of the experiment(P<0.05). The results of space exploration experiments showed that there was no statistical difference on the target quadrant retention time and the number of crossing the platform among the 4 groups(P>0.05). At 1, 30, and 60 min after high-frequency stimulation, the LTP amplitudes in the hippocampus CA1 area of the aluminum-treated groups were lower than that of the control group at the same time point(P<0.05), and the LTP amplitudes of hippocampus CA1 area of rats decreased with the increase of maltol aluminum exposure dose(P<0.01). The relative expression of PI3 K, AKT and mTOR protein in the hippocampus tissues of the aluminum-treated groups was lower than that of the control group(P<0.05), and the relative expression of the above three proteins decreased with the increase of the maltol aluminum exposure dose(P <0.01). CONCLUSION: Sub-chronic aluminum exposure could lead to dose-dependent inhibition of hippocampus synaptic plasticity in rats, thereby impairing the spatial learning ability of rats. This process may be related to inhibition of PI3 K/AKT/mTOR signaling pathway by aluminum.

17.
China Occupational Medicine ; (6): 24-29, 2020.
Article in Chinese | WPRIM | ID: wpr-881859

ABSTRACT

OBJECTIVE: To observe the effect of maltolate aluminum on synaptic plasticity in the hippocampus of rats and to explore the regulatory effect and mechanism of metabotropic glutamate receptor 1(mGluR1). METHODS: Specific pathogen free healthy adult male SD rats were randomly divided into control group, aluminum group, aluminum agonist group and aluminum antagonist group, 8 rats in each group. The rats in the control group received no treatment; the rats in aluminum group were injected with 5 μL 10 mmol/L maltolate aluminum solution into the lateral ventricle; the rats in aluminum agonists and aluminum antagonist group were injected with 3 μL 10 mmol/L maltolate aluminum solution plus 2 μL 0.1 μmol/L mGluR1 agonist or 2 μL 0.2 μmol/L mGluR1 antagonists into the lateral ventricle, respectively.Maltolate aluminum solution was injected every 2 days and continued for 10 days. After maltolate aluminum exposure, the amplitudes of long-term potentiation(LTP) in hippocampal CA1 region of rats were measured, and the relative expression levels of mRNA and protein of mGluR1, N-methyl-D-aspartate receptor(NMDAR1) and protein kinase C(PKC) in hippocampus tissue of rats were detected by real-time fluorescence quantitative polymerase chain reaction and Western blotting. RESULTS: The amplitude of LTP in hippocampal CA1 region in aluminum group and aluminum agonist group was lower than that in the control group and the aluminum antagonist group(P<0.05). Compared with the control group, the relative expression of mGluR1 mRNA and protein in the aluminum group increased, the relative expression of PKC and NMDAR1 mRNA and protein in the aluminum group decreased(P<0.05). Compared with the aluminum group, the relative expression of mGluR1 mRNA and protein in the aluminum agonist group increased, while the NMDAR1 mRNA decreased(P<0.05); the relative expression of mGluR1 mRNA and protein in the aluminum antagonist group decreased, while the NMDAR1 mRNA and protein increased(P<0.05). Compared with the aluminum agonist group, the relative expression of mGluR1 mRNA and protein decreased, while the NMDAR1 mRNA and protein increased in the aluminum antagonist group(P<0.05). The relative expression level of PKC mRNA and protein in aluminum agonist group and aluminum antagonist group was not statistically significant(P>0.05), and there was no statistical significance in these two groups compared with control group and aluminum group(P>0.05). CONCLUSION: Maltolate aluminum exposure can inhibit synaptic plasticity by inhibiting LTP in hippocampus of rats, and the mechanism may be related to the regulation of NMDAR1 expression by mGluR1.

18.
Article in Chinese | WPRIM | ID: wpr-820952

ABSTRACT

In recent years, the use of aluminum-containing additives in the food has received wide public attention. Many studies have shown that excessive exposure to aluminum can cause health damage to human body. This paper will review and evaluate the research progress of aluminum toxicity, domestic and international dietary aluminum exposure assessment, and the feasibility of the control measures on the aluminum intake, to provide relevant evidence for the health risk assessment of aluminum in food.

19.
Article in Chinese | WPRIM | ID: wpr-817688

ABSTRACT

@#【Objective】To investigate whether oral administration of probiotics could improve the aluminum-induced hippocampal inflammation in mice.【Methods】Twenty-four 8-week-old male C57BL/6 mice were randomly divided into 4 groups,6 in each. The mice in control(CON)group,AlCl3-treated(Al)group,probiotics-treated(PO)group and treatment-combined(Al+PO)group were treated with sterile water,oral AlCl3,probiotics in sterile water and a combination of oral AlCl3 and probiotics in sterile water ,respectively. After six weeks of treatment,immunofluorescence staining was used to test the numbers of activated microglia(Iba-1+/CD68+ cells) and the expression level of brain-derived neurotrophic factor(BDNF)in hippocampus;enzyme linked immunosorbent assay(ELISA)was employed to determine the levels of interleukin- 1 β(IL- 1 β) and tumor necrosis factor- α(TNF- α)in serum and hippocampus.【Results】 The morphology revealed that compared with those in CON group,in Al group,the numbers of Iba-1+/CD68+ cells increased significantly(P < 0.01)and the BDNF level decreased significantly(P < 0.01). Compared those in Al group , in Al+PO group ,the numbers of Iba-1+/CD68+ cells were significantly lower(P < 0.01)and the BDNF level significantly higher(P < 0.01). ELISA results showed that compared with those in CON group,in Al group,the levels of IL-1β and TNF- α in serum and hippocampus had a significant rise(P < 0.01). Compared those in Al group,in Al+PO group,the levels of IL- 1 β in serum and hippocampus and TNF-α in hippocampus had a significant reduction (P < 0.01).【Conclusions】Oral probiotics improves the aluminum-induced hippocampal inflammation in mice.

20.
Orinoquia ; 23(2): 36-46, jul.-dic. 2019. tab, graf
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1115038

ABSTRACT

Resumen Los efluentes provenientes del sacrificio de cerdos son una fuente de contaminación debido a las altas concentraciones de materia orgánica, nitrógeno, fósforo, grasas, sólidos totales y coliformes fecales. En esta investigación se evaluó la efectividad del quitosano como coagulante en el postratamiento de efluentes porcícolas provenientes de un reactor discontinuo secuencial, con el fin de remover las fracciones no biodegradables remanentes del proceso biológico. El tratamiento terciario consistió en la coagulación, floculación y sedimentación. Se caracterizó el efluente tratado biológicamente mediante los siguientes parámetros: pH, DQO, turbidez, color, sólidos totales (ST), nitrógeno total Kjeldahl (NTK), nitrito, nitrato, fosforo total (PT) y alcalinidad total (AT). El tratamiento fisicoquímico se llevó a cabo mediante el uso de la prueba de Jarra a través de corridas exploratorias con dosis entre 50 y 800 mg/L de quitosano disuelto en ácido acético. Se comparó la efectividad del quitosano (700 mg/l) con sulfato de aluminio (430mg/l) y poliacrilamida (90 mg/l), los cuales son utilizados como coagulantes de uso convencional en el tratamiento de aguas residuales. El experimento se condujo mediante un diseño completamente al azar con un total de tres tratamientos (quitosano, sulfato de aluminio y poliacrilamida) y tres repeticiones cada uno. La dosis de quitosano (700 mg/l) permitió obtener porcentajes de reducción de turbidez de 83,1%, color de 64,7%, DQO de 84,6%, y 78,2% de NT para valores iniciales de 15,6 NTU, 26 UC Pt-Co, 865 mg DQO/L y 89 mg NT/L. Se encontraron diferencias significativas (P≤0,05) entre la dosis quitosano (700 mg/l) y los coagulantes convencionales (430 mg/l de sulfato de aluminio y 90 mg/l de poliacrilamida) en la reducción de NT, siendo el tratamiento con quitosano el coagulante con las mayores eficiencias de reducción. El tratamiento con quitosano con una dosis de 700 mg/l representó una opción viable para el tratamiento terciario de los efluentes proveniente del proceso de sacrificio de cerdos tratados biológicamente.


Abstract Effluents from pig slaughter are a source of contamination due to high concentrations of organic matter, nitrogen, phosphorus, fats, total solids and fecal coliforms. This research evaluated the effectiveness of chitosan as a coagulant in the post-treatment of wastewater from the slaughter of pigs, in order to remove the remaining recalcitrant fractions from the biological process in a sequential batch reactor. The tertiary treatment consisted of coagulation, flocculation and sedimentation. The effluent was characterized by the parameters: pH, COD, turbidity, color, total solids (ST), Kjeldahl total nitrogen (NTK), nitrite, nitrate, total phosphorus (PT) and total alkalinity (AT). The treatment was carried out by using the jar test through exploratory runs with doses between 50 and 800 mg/L of chitosan dissolved in acetic acid. The effectiveness of chitosan with conventional coagulants in the treatment of wastewater, such as aluminum sulphate and polyacrylamide, was compared. The experiment was conducted using a completely randomized design with a total of three treatments and three replicates each. The evaluated range of doses of chitosan allowed to obtain percentages of turbidity removal of 83,1%, color of 64,7%, COD of 84,6%, and 78,2% NT for initial values ​​of 15,6 NTU, 26 UC, 865 mg COD/L and 89 mg NT/L, using as optimal dose 700 mg chitosan /L. Significant differences (P≤0,05) were found between chitosan and conventional coagulants in NT removal, with chitosan being the coagulant with the highest removal efficiencies. The treatment with chitosan represents a viable option for the tertiary treatment of the effluents coming from the slaughter of pigs.


Resumo Efluentes de abate de suínos são uma fonte de contaminação devido às elevadas concentrações de matéria orgânica, azoto, fósforo, gordura, sólidos totais e coliformes fecais. Nesta pesquisa foi avaliada a eficácia de quitosana como um coagulante nos efluentes porcícolas de pós-tratamento, a fim de remover restantes fracções recalcitrantes de um processo biológico em um reactor de carregamento sequencial. O tratamento terciário consistiu em coagulação, floculação e sedimentação. O efluente tratado foi caracterizado biologicamente pelos parâmetros: pH, DQO, turbidez, cor, sólidos totais (ST), nitrogênio total Kjeldahl (NTK), nitrito, nitrato, fósforo total (PT) e alcalinidade total (AT). O tratamento foi realizado usando jarro teste é executado através exploratórios com doses entre 50 e 1250 mg / L de quitosano dissolvido em ácido acético. A eficácia do quitosano com sulfato de alumínio y poliacrilamida foi comparada. O experimento foi conduzido usando um desenho completamente aleatório com um total de três tratamentos e três repetições. A gama de dose de quitosana avaliada produziu percentagens de remoção de turvação de 83,1% cor 64,7% de CQO de 84,6%, e 78,2% de NT para os valores iniciais de 15,6 NTU, 26 UC Pt-Co, 865 mg CQO / L e 89 mg de NT / L, usando dose óptima de 700 mg de quitosana/L. Diferenças significativas (P≤0,05) entre quitosano e coagulantes convencionais na remoção de NT foram encontrados para ser um tratamento com o coagulante quitosano com as eficiências mais altas de remoção. O tratamento com quitosana representa uma opção viável para o tratamento terciário do efluente opção abate de porco.

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