In-vivo bone response to titanium screw implants anodized in sodium sulfate

PURPOSE: To evaluate the early bone response to a nanotextured dental implant treated with sodium sulfate (Na2SO4), using a rabbit model. METHODS: Twelve animals were randomly divided into group 1 (Control) - machined implants and group 2 (Test) - nanotextured implants. Extra-oral incision was performed to provide access to intended surgical site where the dental implant was inserted immediately after the extraction of the mandibular first premolar. Implant surface characterization was performed by scanning electron microscopy attached to energy dispersive spectroscopy and interferometry. Three weeks after surgery, the animals were induced to death and undecalcified sections of the samples were prepared for histological and histomorphometrical analysis. RESULTS: Surface characterization of the implant demonstrated enhanced surface area of anodized group compared to Control group with 19.2% ± 6.2 versus 1.6 ± 0.7, respectively. Histological evaluation demonstrated new bone formation starting from the buccal and lingual cortical walls on both groups. After three weeks, significant higher bone contact of 27% (p<0.05) was observed to nanotextured compared to machined implants (Control group). CONCLUSION: The anodization with sodium sulfate nanostructures to the implant surface that resulted in faster osseointegration. .

Effect of denture cleansers on metal ion release and surface roughness of denture base materials

Chemical disinfectants are usually associated with mechanical methods to remove stains and reduce biofilm formation. This study evaluated the effect of disinfectants on release of metal ions and surface roughness of commercially pure titanium, metal alloys, and heat-polymerized acrylic resin, simulating 180 immersion trials. Disk-shaped specimens were fabricated with commercially pure titanium (Tritan), nickel-chromium-molybdenum-titanium (Vi-Star), nickel-chromium (Fit Cast-SB Plus), and nickel-chromium-beryllium (Fit Cast-V) alloys. Each cast disk was invested in the flasks, incorporating the metal disk to the heat-polymerized acrylic resin. The specimens (n=5) were immersed in these solutions: sodium hypochlorite 0.05%, Periogard, Cepacol, Corega Tabs, Medical Interporous, and Polident. Deionized water was used as a control. The quantitative analysis of metal ion release was performed using inductively coupled plasma mass spectrometry (ELAN DRC II). A surface analyzer (Surftest SJ-201P) was used to measure the surface roughness (µm). Data were recorded before and after the immersions and evaluated by two-way ANOVA and Tukey's test (α=0.05). The nickel release proved most significant with the Vi-Star and Fit Cast-V alloys after immersion in Medical Interporous. There was a significant difference in surface roughness of the resin (p=0.011) after immersion. Cepacol caused significantly higher resin roughness. The immersion products had no influence on metal roughness (p=0.388). It could be concluded that the tested alloys can be considered safe for removable denture fabrication, but disinfectant solutions as Cepacol and Medical Interporous tablet for daily denture immersion should be used with caution because it caused greater resin surface roughness and greater ion release, respectively.

Desinfetantes químicos são normalmente associados a métodos mecânicos para remover manchas e reduzir a formação do biofilme. Este estudo avaliou o efeito de desinfetantes na liberação de íons metálicos e na rugosidade superficial do titânio comercialmente puro, ligas metálicas e resina acrílica termopolimerizável, simulando 180 ensaios de imersões. Espécimes em formato de discos foram confeccionados com titânio comercialmente puro (Tritan), liga de níquel-cromo-molibdênio-titânio (Vi-Star), liga de níquel-cromo (Fit Cast-SB Plus) e liga de níquel-cromo-berílio (Fit Cast-V). Os espécimes (n=5) foram imersos nestas soluções: hipoclorito de sódio a 0,05%, Periogard, Cepacol, Corega Tabs, Medical Interporous e Polident. Como controle, foi utilizada a água deionizada. A análise quantitativa de liberação de íons metálicos foi realizada por meio de espectrometria de massa com plasma indutivamente acoplado (ELAN DRC II). O rugosímetro (Surftest SJ-201P) foi utilizado para medir a rugosidade superficial (µm). Os dados foram registrados antes e depois das imersões e avaliados por ANOVA com dois fatores e teste de Tukey (α=0,05). A liberação de níquel provou ser mais expressiva nas ligas Vi-Star e Fit Cast-V após a imersão em Medical Interporous. Houve diferença significante na rugosidade superficial da resina (p=0,011) após a imersão. O Cepacol causou maior rugosidade superficial de forma significativa. Os produtos de imersão não influenciaram nos resultados da rugosidade do metal (p=0,388). Pode-se concluir que as ligas metálicas testadas podem ser consideradas seguras para a fabricação de próteses removíveis, mas as soluções desinfetantes como o Cepacol e a pastilha Medical Interporous para a imersão diária da prótese devem ser utilizados com cautela, pois causaram maior rugosidade superficial da resina e maior liberação de íons, respectivamente.

Effect of different cleansers on the surface of removable partial denture

Removable partial dentures (RPD) demand specific hygienic cleaning and the combination of brushing with immersion in chemical solutions has been the most recommended method for control of biofilm. However, the effect of the cleansers on metallic components has not been widely investigated. This study evaluated the effect of different cleansers on the surface of RPD. Five disc specimens (12 mm x 3 mm metallic disc centered in a 38 x 18 x 4 mm mould filled with resin) were obtained for each experimental situation: 6 solutions [Periogard (PE), Cepacol (CE), Corega Tabs (CT), Medical Interporous (MI), Polident (PO), 0.05 percent sodium hypochlorite (NaOCl), and distilled water (DW) control] and 2 Co-Cr alloys [DeguDent (DD) and VeraPDI (VPDI)] were used for each experimental situation. A 180-day immersion was simulated and the measurements of roughness (Ra, µm) of metal and resin were analyzed using 2-way ANOVA and Tukey’s test. The surface changes and tarnishes were examined with a scanning electronic microscopy (SEM). In addition, energy dispersive x-ray spectrometry (EDS) analysis was carried out at representative areas. Visually, NaOCl and MI specimens presented surface tarnishes. The roughness of materials was not affected by the solutions (p>0.05). SEM images showed that NaOCl and MI provided surface changes. EDS analysis revealed the presence of oxygen for specimens in contact with both MI and NaOCl solutions, which might suggest that the two solutions promoted the oxidation of the surfaces, thus leading to spot corrosion. Within the limitations of this study, it may be concluded that the NaOCl and MI may not be suitable for cleaning of RPD.

As próteses parciais removíveis (PPR) exigem higienização específica e a associação da escovação com imersão em soluções químicas tem sido o método mais recomendado para controle do biofilme. Entretanto, os efeitos destas soluções não são amplamente reportados em componentes metálicos. Este estudo avaliou o efeito de diferentes agentes de higienização na superfície dos componentes de uma PPR. Foram confeccionados 5 espécimes (disco metálico de 12 x 3 mm centralizado em uma tira de resina com 38 x 18 x 4 mm) para cada situação experimental: 6 soluções [Periogard (PE), Cepacol (CE), Corega Tabs (CT), Medical Interporous (MI), Polident (PO), hipoclorito de sódio 0,05 por cento (HS) e água destilada (AD) como controle)] e 2 ligas de cobalto-cromo [DeguDent (DD) e Vera PDI (VPDI)] foram utilizadas para cada situação experimental. Foram simuladas imersões de 180 dias. As aferições de rugosidade (Ra, μm) tanto em porção metálica quanto em resina acrílica termopolimerizável foram submetidos ao ANOVA e ao teste de Tukey. As alterações superficiais e manchas foram examinadas por meio de microscopia eletrônica de varredura (MEV). Áreas de interesse foram submetidas à espectrometria por energia dispersiva por raios X (EDS). Visualmente, puderam ser verificadas manchas nas superfícies metálicas quando utilizados HS e MI. A rugosidade dos materiais não foi afetada pelas soluções (p>0,05). As fotomicrografias evidenciaram que HS e MI ocasionaram alterações superficiais. As análises de EDS revelaram a presença de oxigênio nos grupos HS e MI, o que pode sugerir que estas duas soluções causaram oxidação das superfícies, provocando pontos de corrosão. Dentre as limitações do presente estudo, pode-se concluir que estas soluções não são apropriadas para a higienização das PPR.

Antimicrobial activity of flavanoid sulphates and other fractions of Argyreia speciosa (Burm.f) Boj.

Antimicrobial activity of flavanoid sulphates and different fractions of A. speciosa root was studied against bacteria, fungi and Mycobacterium tuberculosis H37 Rv sensitive strain by in vitro and in vivo assays. Flavanoid sulphates such as quercetin 3'7 di-O methyl 3- sulphate and kaempferol 7-O methyl 3-sulphate were isolated from the n-butanol fraction of 80% methanolic extract of the plant. The structures of the isolated flavanoids were confirmed by spectral studies. Ethyl acetate (EAAS) fraction and flavanoid sulphates inhibited the growth of M. tuberculosis Rv sensitive strain at MIC values 50 and 25 microg/ml, respectively. Ethanolic fraction (EtAS) showed significant inhibition of gram positive organism with a MIC of 31.25 microg/ml. More inhibition was observed with a less MIC (2 microg/ml) for flavanoid sulphates against Klebsiella pneumoniae, a gram negative organism and it is almost comparable with the standards. Interestingly, chloroform fraction alone exhibited significant antifungal activity with a MIC of 100 microg/ml. A synergistic effect between flavanoids sulphates and commercially available antitubercular drugs was observed with FIC index of 0.443 +/- 0.245, 0.487 +/- 0.247 for isoniazid and 0.468 +/- 0.333, 0.417 +/- 0.345 for rifampicin, whereas EAAS fraction showed partial synergistic effect. A synergistic effect was observed for EAAS fraction and flavanoids sulphates with FIC index < 0.5 with antibiotics. Hemolysis assay on RBCs suggested that EAAS and flavanoids sulphates exhibited least cellular toxicity to erythrocytes as compared to chloramphenicol. In vivo studies in mice infected with K. pneumoniae demonstrated that on day 10 post treatment of different fractions and isolated compounds of A. speciosa, about 60% of the animals treated with EAAS, 70% of animals treated with flavanoids sulphates and 40% of animals treated with EtAS were survived.

Solubilization of water-insoluble beta-glucan isolated from Ganoderma lucidum.

The fungal beta-D-glucan is a biological response modifier (BRM), but a major obstacle to the clinical utilization of beta-glucan BRMs is thei relative lack of solubility in aqueous media. Water insoluble fungal glucans extracted by alkali from the mycelia of Ganoderma lucidum were sulfated to yield their corresponding water-soluble derivatives. Insoluble glucan is dissolved in methyl sulfoxide and urea, and is partially sulfated with sulfuric acid. The sulfated glucan (SGL) yield prepared from insoluble glucan (IGL) was 85%, the sulfation degree of SGL was about 14.9%, and the solubility of SGL was above 95% in water. The monosugar SGL content was 34.9% alpha-glucose and 35.9% beta-glucose. The mean molecular weight (MW) of SGL was shown as a single peak on Sepharose CL-4B column chromatography, and their MW was approximately 9.3 kDa. The 13C NMR spectrum analysis shows that SGL has a high similarity with the beta-(1-->3)-linked triple-helical control.

Obtaining different color tones via burn out printing on blended fabric

Different blended fabrics comprise polyamide/viscose, polyester/linen, wool/polyester and polyester/cotton were subjected to burn out using Aluminum sulphate, Sodium phosphate, Aluminum potassium sulphate, Di-hydrogen phosphate, Caustic soda or Formic acid. The loss weight was found to depend on both the nature of fabric and the chemical used as well as the concentration of the latter. Different color tones could be obtained on dyeing the burn out blends using a natural dye namely Rhubarb powder. The effect of burn out was evaluated via measuring the loss in weight, K/S as well as the overall fastness properties of the dyed fabrics

Studies on acceleration of Ras cheese ripening by aminopeptidases enzyme from buffaloes' pancreas. I. purification and characterization of buffaloes pancreas aminopeptidas

Aminopeptidaes [EC. 3.4.11.1] was purified from fresh buffaloes pancreas by ammonium sulfate fractionation at 30-40% saturation [w/v], followed by gel filtration chromatography on sephadex G-l 00 column about 9.6 fold with 20% recovery of crude extract. The enzyme had a molecular weight [MW] about 20 kDa by gel filtration chromatography on sephadex G 100 column. The purified enzyme exhibited maximum activity on leucine-p-nitroanilide pH 6.0 and 40°C. The enzyme was strongly activated by 1 mM of Ca [+2], Na[+], respectively, but strongly inhibited by 1 mM of Cu[+]2 and Cd[+]2. The purified aminopeptidase activity was not significantly affected by I mM of EDTA and 1, 10 Phenanthroline

Physico-chemical and biological study of the river Chittar at Courtallam, Tamil Nadu (India).

Courtallam Falls of the river Chittar in Tamil Nadu (India) is a place of tourist attraction during the southwest monsoon season. Particularly, in this season high input of detergents and other anthropogenic activities tend to bring in undesirable materials into the water body, whereby the pristine quality is altered. Therefore, a study was undertaken in the peak southwest tourist season to assess physico-chemical and biological quality of the river Chittar. After carrying out analytical study of various water samples, it was found that although the river was not found highly polluted, biological quality was found significantly poor. Excluding sulphate, all the other physico-chemical parameters analyzed were found within the permissible limits. However, the total and faecal coliforms exceeded the permissible limits, indicating a poor status of the river.

Textile anionic dyes recovery using tri-n-butyl phosphate as carrier through supported liquid membrane.

The recovery of anionic dyes Acid Red10 B (CI Acid Violet 54) and Acid Pink BE (CI Acid Red 183) in flat type supported liquid membrane (SLM) using tri-n-butyl phosphate as carrier was studied. The parameters studied were the effect of feed phase pH, stripping reagent concentration, string speed and initial dye concentration on permeability of dyes. The influence of salt concentration such as sodium chloride and sodium sulphate on the dye recovery was examined. The reusability of membrane and kinetics of transport were also studied. The optimum conditions of transport are feed phase pH 1 +/- 0.1, 0.1 M sodium hydroxide as stripping phase, stirring speed at 500 rpm. The maximum recovery under optimum conditions was observed as 94.2 % for Acid Red10 B and 85.7 % for Acid Pink BE. The maximum permeability was 11.0 x 10(-6) m/s for Acid Red10 B and 7.7 x 10(-6) m/s for Acid Pink BE.

The specificity of interactions between proteins and sulfated polysaccharides

Os polissacarídeos sulfatados são capazes de se ligar às proteínas com diferentes níveis de especificidade. São macromoléculas altamente ácidas que podem se ligar de forma inespecífica a qualquer domínio básico da superfície de uma proteína em soluções com baixa força iônica, contudo tais interações não parecem ser fisiologicamente significativas. Por outro lado, foram identificados vários sistemas nos quais componentes estruturais muito específicos dos polissacarídeos sulfatados conferem alta afinidade para algumas proteínas. O exemplo mais conhecido é o pentassacarídeo da heparina com alta afinidade pela antitrombina. Outros exemplos podem ser observados no estudo de invertebrados marinhos, tais como a importância da estrutura fina do dermatam sulfato para sua interação com o cofator II da heparina e o envolvimento defucanas sulfatadas encontradas no gel que envolve osóvulos dos ouriços-do-mar na espécie especificidade da fertilização. Um terceiro exemplo de interação específica é aquele descrito para o glicosaminoglicano heparam sulfato encontrado na superfície celular. Neste caso, o padrão de sulfatação pode determinar diferentes afinidades do carboidrato por citoquinas, fatores de crescimento e outras proteínas encontradas na superfície celular e na matriz extracelular. Estas interações complexas entre proteínas e carboidratos são capazes de influenciar a difusão das proteínas através dos tecidos, assim como modelar a resposta celular a estas moléculas.

Leaching of As(III) and As(V) from exhausted calsico--a case study.

Batch leaching experiments were conducted to estimate the leaching of As(III) and As(V) from exhausted CalSiCo.The leaching of As(III) and As(V) was found to be function of time and concentrations of anions such as Cl-, NO3-, SO4(2-) in extraction fluid. Extraction tests were carried out to determine the maximum leachable concentration under the chosen conditions of leaching medium and leaching time. It has been observed that the leaching of As(III) is more than As(v) in all the cases. Leaching of As(III) and As(v) from exhausted CalSiCo is also carried out in rainwater and in tap water. It is observed that leaching of As is more in rainwater than tap water. Further higher leaching is observed in case of fluids containing chloride compared to those containing nitrate and sulphate.

Acetate utilization by sulfate reducing bacteria in an uaff reactor

Industrial development in Egypt, like in many other developing countries in the world, is causing serious environmental problems due to the increasing influence of the disposal of heavy metals and organic wastes in the natural water bodies and on the land. Such pollutants in water, soil and air environments are causing damaging impact on the health of all the living beings. This study was carried out to develop new processes for the treatment of heavy metals and organic wastes, which can be considered as environment friendly, and will cause minimum damage to the environment and human health. The proposed method for the removal of heavy metals and organic matter from the waste stream is based on the use of sulfate reducing bacteria which convert sulfate to sulfide which in turn remove metals as metal sulfide. The sulfate reducing bacteria, SRB, have been used widely for the removal of heavy metals from industrial wastewaters. In this research, it was decided to determine the optimum controlling factors affecting the growth of the SRB utilizing acetate as an organic carbon source in an up flow anaerobic fixed film reactor, UAFFR. A series of continuous flow experiments were carried out to measure the optimum values for these parameters. Substrate, containing acetate as the organic carbon source along with other nutrients such as sulfate, ammonia and phosphates was fed to the experimental units. It was found experimentally that the optimum SRB growth activity occurred with an organic loading rate, OLR, of 6 kg/d/m[3], and the theoretical oxygen demand to sulfate ratio, Th.O.D./SO[4], ranged from 1.5 to 2.0. The optimum hydraulic retention time HRT was found to be equal to or higher than 11 hours. The effect of the reactor's packing material on SRB growth was also studied. Different packing materials with different surface areas were used. It was shown that the SRB growth does not depend on the nature of the packing material of the reactor

A carbon-limited medium for growth and sporulation of Bacillus thuringiensis var. kurstaki.

A culture medium for batch production of d-endotoxin by Bacillus thuringiensis (B., t.) has been modified. Through batch and continuous cultivation studies, the original medium was diagnosed to be limited in organic nitrogen. Corn steep liquor was found to be an excellent source for the organic nitrogen and its addition resulted in a carbon limited medium and in a significant increase in the amount of spore-toxin complex formed in shake flasks. Results of bioassay, conducted on Trichoplusia ni, suggest enhancement of larvicidal efficacy under carbon-limited growth conditions.