Hybrid Implants Based on Calcium-Magnesium Silicate Ceramic Diopside as a Carrier of Recombinant BMP-2 and Demineralized Bone Matrix as a Scaffold: Ectopic Osteogenesis in Intramuscular Implantation in Mice.

High efficiency of hybrid implants based on calcium-magnesium silicate ceramic, diopside, as a carrier of recombinant BMP-2 and xenogenic demineralized bone matrix (DBM) as a scaffold for bone tissue regeneration was demonstrated previously using the model of critical size cranial defects in mice. In order to investigate the possibility of using these implants for growing autologous bone tissue using in vivo bioreactor principle in the patient's own body, effectiveness of ectopic osteogenesis induced by them in intramuscular implantation in mice was studied. At the dose of 7 µg of BMP-2 per implant, dense agglomeration of cells, probably skeletal muscle satellite precursor cells, was observed one week after implantation with areas of intense chondrogenesis, initial stage of indirect osteogenesis, around the implants. After 12 weeks, a dense bone capsule of trabecular structure was formed covered with periosteum and mature bone marrow located in the spaces between the trabeculae. The capsule volume was about 8-10 times the volume of the original implant. There were practically no signs of inflammation and foreign body reaction. Microcomputed tomography data showed significant increase of the relative bone volume, number of trabeculae, and bone tissue density in the group of mice with BMP-2-containing implant in comparison with the group without BMP-2. Considering that DBM can be obtained in practically unlimited quantities with required size and shape, and that BMP-2 is obtained by synthesis in E. coli cells and is relatively inexpensive, further development of the in vivo bioreactor model based on the hybrid implants constructed from BMP-2, diopside, and xenogenic DBM seems promising.

[Potential to Ensure Safe Production from Rice Fields Polluted with Heavy Cadmium by Combining a Rice Variety with Low Cadmium Accumulation, Humic Acid, and Sepiolite].

The study investigated the potential of ensuring safe production of rice from paddy fields affected by heavy cadmium contamination. A paddy soil polluted with heavy cadmium (total Cd content of 2.52 mg·kg-1) surrounding a lead-zinc mining area in Guiyang County of Chenzhou City, Hunan province was selected for analysis. We investigated production using a low cadmium accumulation rice variety (Oryza sativa L. Jia-33) and passivation additives for heavy metal activity (including humic acid and sepiolite). Results showed that:Oryza sativa L. Jia-33 showed good low cadmium accumulation characteristics in rice fields with heavy cadmium pollution. When humic acid and sepiolite were applied (alone or combined), the accumulation of Cd in different organs of the rice declined, and the transport coefficient of Cd for stem to root and polished rice to stem also declined. The rate of decline increased with increased application dosage. The cadmium content in polished rice was lower than the limit established in the National Food Safety Standard (GB 2715-2012), when applying 5.250 t·hm-2 humic acid, 6.750 t·hm-2 sepiolite, or a combination of 1.125 t·hm-2 humic acid and 3.37 5 t·hm-2 sepiolite; Cd content in polished rice was (0.171±0.01), (0.184±0.01), and (0.181±0.01) mg·kg-1, respectively. Single or combined application of humic acid and sepiolite promoted the transformation of soil Cd to residual and Fe Mn oxide bound forms, significantly reducing the content of available Cd and the bioavailability of Cd in soil, and further reducing Cd content in all rice organs. The reduction was more effective with single application of sepiolite or combined application of humic acid and sepiolite. The effects of combined application of humic acid and sepiolite were also more beneficial for soil nutrients, while soil available phosphorus, available potassium, phosphorus, and organic matter content increased with increased application of amendments. Soil nitrogen content did not change. In conclusion, results indicate that joint application of humic acid, sepiolite, and a low Cd accumulation rice variety are best for safe production on heavy cadmium-contaminated soil.

Influence of sepiolite additions to different litter materials on performance and some welfare parameters of broilers and litter characteristics.

The litter quality is an important factor affecting the performance, welfare and carcass quality of the broilers. Depending on the progress of the fattening duration, some materials may be added to the litter in order to keep the pH, moisture and ammonia levels in the litter under control. Sepiolite is a natural material and it has strong absorbing ability to the water. Therefore, the aim of this study was to determine the effects of sepiolite additions to different litter materials on performance and some welfare parameters of broilers and litter characteristics. A total of 288 1-d-old male broiler chicks (ROSS-308) were used. Birds were randomly allocated to 2 litters (wood shavings and rice hull) and 3 sepiolite groups (0, 25, 50%) with 6 replication, and each pen contains 8 chicks. Fattening performance, IgG, tonic immobility period, feather score, skin injures, breast burns, and footpad burns of broilers were not affected significantly by sepiolite additions to the litter. However, sepiolite addition to the litter can improve litter quality. There was no significant difference between 2 litter materials because both have same color. There were no significant interactions in examined parameters. In conclusion, addition of sepiolite at 25 and 50% levels to litter materials may be used as a litter material in the broiler production without adverse welfare and performance problem.

Infrared Spectroscopy for Analysis of Co-processed Ibuprofen and Magnesium Trisilicate at Milling and Freeze Drying.

Assessment of interactions of ibuprofen and magnesium trisilicate after co-processing has been carried out by infrared spectroscopy. Dry-state ball-milling and, aqueous state kneading and freeze-drying were performed. FTIR spectroscopy of co-processed materials described acid-base reaction between the carboxylic acid containing ibuprofen to a significant extent. Increased absorbance of carboxylate peak accompanied by a consistently reduced absorbance of the carbonyl acid peak was evident. Absorbance of carboxylate peak was more in freeze-dried sample compared to milled product. Intermolecular hydrogen bonding between ibuprofen and magnesium trisilicate in the co-processed material has been suggested. Inhibition of crystal morphology has been noticed in the photomicrographs of both the products. DSC report has shown absence or significantly decreased melting endotherm representing almost complete amorphization of ibuprofen. Release of drug increased greatly after co-processing in comparison to crystalline ibuprofen. Freeze-dried samples have improved drug release more significantly compared to ball-milled samples.

Rapid DNA transformation in Salmonella Typhimurium by the hydrogel exposure method.

Even with advances in molecular cloning and DNA transformation, new or alternative methods that permit DNA penetration in Salmonella enterica subspecies enterica serovar Typhimurium are required in order to use this pathogen in biotechnological or medical applications. In this work, an adapted protocol of bacterial transformation with plasmid DNA based on the "Yoshida effect" was applied and optimized on Salmonella enterica serovar Typhimurium LT2 reference strain. The plasmid transference based on the use of sepiolite as acicular materials to promote cell piercing via friction forces produced by spreading on the surface of a hydrogel. The transforming mixture containing sepiolite nanofibers, bacterial cells to be transformed and plasmid DNA were plated directly on selective medium containing 2% agar. In order to improve the procedure, three variables were tested and the transformation of Salmonella cells was accomplished using plasmids pUC19 and pBR322. Using the optimized protocol on Salmonella LT2 strain, the efficiency was about 10(5) transformed cells per 10(9) subjected to transformation with 0.2µg plasmid DNA. In summary, the procedure is fast, offers opportune efficiency and promises to become one of the widely used transformation methods in laboratories.

A novel multifunctional pharmaceutical excipient: modification of the permeability of starch by processing with magnesium silicate.

A directly compressible excipient has been developed by co-processing starch with magnesium silicate. The foregoing was achieved either by co-precipitation of magnesium silicate onto different types of starch or by dry granulation of maize starch with magnesium silicate. A variety of techniques (permeability, water retention/swelling, compression analysis, scanning electron microscopy, tensile strength and disintegration/dissolution studies) were used to characterize these systems. The permeability of the formulations produced using the two methods was evaluated experimentally using Darcy's permeability law. Magnesium silicate, as an anti-adhering agent, increases the permeability of both maize and partially pregelatinized starch, resulting in compacts of high mechanical strength, short disintegration time and low lubricant sensitivity. Such advantages are evident when the properties of the physical mixture of maize starch with magnesium silicate are compared with the co-precipitation and dry granulation techniques. Formulation with this novel excipient system, using paracetamol as a model drug, indicated its suitability as a single multifunctional excipient.

Occurrence and bioaccumulation study of PCDD and PCDF from mineral feed additives.

Extraction of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) was evaluated in sepiolite matrices. Soxhlet extraction using different extracting strategies and acid treatment were tested. Acid treatment or Soxhlet extraction using a mixture of toluene:ethanol as solvent allowed to reach the minimum requirements for recovery rates. However, Soxhlet extraction using a mixture cyclohexane:toluene as extracting solvent did not allow to comply with these minimum requirements. Significant differences were obtained in TEQ units when acid treatment was applied in comparison to Soxhlet extraction. This fact can be explained because the use of drastic acid conditions allows removing strongly adsorbed analytes which can be uniquely extracted after a total destruction of the crystalline. On the contrary, Soxhlet extraction was not able to destroy the structure of sepiolite and as a consequence the PCDDs/Fs remain adsorbed in the internal structure of the mineral. A bioaccumulation study was also conducted to evaluate the transference of PCDDs/Fs from the sepiolite into the animal when fed with feed containing sepiolite. Four groups of chickens were exposed through diet to a control feed, feed with 3% w/w sepiolite, spiked feed contaminated with PCDDs/Fs and feed containing contaminated kaolinitic clay. Livers of animals were analyzed throughout the exposure period. Results of this trial showed that the performance of broilers was not affected by the presence of dioxins at levels tested, and chickens did not show any abnormal behaviour. Dioxins intentionally added to the diet were significantly absorbed and accumulated in liver, whereas the PCDDs/Fs from sepiolite were not available for chickens since livers from broilers fed 3% sepiolite presented similar WHO-TEQ values than those from broilers fed control diet.

Discovery and application of the Yoshida effect: nano-sized acicular materials enable penetration of bacterial cells by sliding friction force.

Bacterial genetic properties can be readily altered by a range of techniques, for example, when a mixture of recipient bacteria, donor genes, and nano-sized acicular material are stimulated by sliding friction on surface of the hydrogel such as agarose or gellan gum. In this particular case, a phenomenon called the Yoshida effect is responsible. Specially designed apparatus has been developed to investigate this effect in an effort to identify technical applications, such as the quantitative detection of asbestos. Current patents related to plasmid transformation methods for prokaryotes and quantitative detection of environmental asbestos are also presented.

Significance of the quality of Florisil in organochlorine pesticide analysis.

During the analysis of chlorinated pesticides in animal fat tissue applying the matrix solid-phase dispersion method, and notwithstanding the use of a gas chromatograph with a highly selective capillary column, two peaks occur: one with a retention time very similar to that of lindane, and the other almost identical to that of dieldrin. Repeated analyses of the same sample with a GC/MS system revealed that neither lindane nor dieldrin were present. It was proven that those peaks resulted from florisil of local origin used for analysis, but not from the original Florisil. The removal of the first peak ("lindane") was possible through heating of florisil of local origin at 680 degrees C for 4 hours, whereas some other method would be required for the removal of the other peak ("dieldrin"). The incident proved that, in such demanding analyses, it is extremely important to use original, high quality substances to avoid possible interference and misinterpretation of results.