Search

We presented a control strategy for tablet manufacturing processes based on continuous direct compression. The work was conducted by the experts of pharmaceutical companies, machine suppliers, academia, and regulatory authority in Japan. Among different items in the process, the component ratio and blended powder content were selected as the items requiring the control method specific to continuous manufacturing different from the conventional batch manufacturing. The control and management of the Loss in Weight (LIW) feeder were deemed the most important, and the Residence Time Distribution (RTD) model were regarded effective for setting the control range and for controlling of the LIW feeder. Based on these ideas, the concept of process control using RTD was summarized. The presented contents can serve as a solid fundament for adopting a new control method of continuous direct compression processes in and beyond the Japanese market., (© 2020 Shenyang Pharmaceutical University. Published by Elsevier B.V.)

For monitoring the regenerated bioactivity of a masked bioactive compound, resveratrol (a luciferase inhibitor) was selected to target such a compound. Caged resveratrol, masked by thiochromone-type photolabile-protecting groups was synthesized in the study. Each caged resveratrol showed lower bioactivity when compared to that shown by the original molecule. After photoirradiation, the original bioactivity was found to be regenerated. Furthermore, the fluorescent compound derived from the thiochromone-type photolabile-protecting groups was generated simultaneously. A linear correlation was observed between the regenerated bioactivity and generated fluorescence intensity. Thus, we quantitatively monitored the recovered bioactivity successfully by measuring the fluorescence., Competing Interests: The authors declare no competing financial interest.

Squamous cell carcinoma is frequently observed on the lateral eyebrow, one of the most difficult sites for one-stage reconstruction because of its location close to the eyelids. The reconstruction of defects by the single-stage flap is advantageous for elderly patients because of its good functional and aesthetic outcome. We surgically treated three cases of squamous cell carcinoma on this area and performed reconstruction with a simply designed bilobed flap, all of which resulted in favorable outcomes. We therefore report on the usefulness of this reconstructive method for the lateral eyebrow defects., (© 2014 Japanese Dermatological Association.)

The purpose of this study was to clarify the stability of benzoyl peroxide (BPO) in some solvents. BPO was dissolved in acetone, acetonitrile (AcCN), 50% acetonitrile-50% distilled water (50% AcCN), ethyl alcohol (EtOH), and methyl alcohol (MeOH). Solutions containing BPO were incubated for eight days at 25 degrees C. In MeOH, BPO rapidly decomposed into benzoic acid (BA) and methyl benzoate (MeBA) time-dependently, whereas BPO in acetone, AcCN, and 50% AcCN was relatively stable. Although BPO in EtOH was slightly stable within the first 24 hours, it decomposed time-dependently such that BA and EtBA as decomposition products of BPO were produced. These results indicated that the stability of BPO in a solution was dependent on the solvent and the decomposition rate of BPO dissolved in MeOH was the fastest. These suggest that BPO can decompose even in lower-than-activation temperature by the solvent to use for its dissolution.

The purpose of the this study was to evaluate the cytotoxicity of dental resin monomers in the presence of a rat liver S9 mix containing cytochrome P 450 enzymes. JTC-12 cells derived from a monkey kidney were seeded on a 96-well multi-well-plate at 9 x 10(3) cells per well. After cultivation, the S9 mix was added to the wells as an S9 mix group (+S9), and PBS- was added to the other wells as a none-S9 mix group (-S9), then 7 different concentrations of various monomers were added to each well. All the specimens were cultured for another 24 hrs. The cell survival ratios (CSR) were calculated by using a neutral red cytotoxicity assay. CSR for 50 micrograms/mL of Bis-GMA/S9 mix was 92.6% while for none-S9 mix it was 6.6%. The values of CSR for UDMA, Bis-MPEPP, EGDMA, TEGDMA, DMAEM, 4-META and HEMA exhibited a reduction in cytotoxicity in the presence of the S9 mix. There were significant differences between +S9 and -S9 for respective monomers (p < 0.05). However, there were no significant differences between +S9 and -S9 for MMA (p < 0.05).

2,5-Dimethyl-4-hydroxy-3(2 H)-furanone (DMHF), produced by Maillard reaction of sugar/amino acid and found in various foodstuffs, showed mutagenicity to Salmonella typhimurium TA100 strain with and without S9 mix, and induced micronucleated mouse peripheral reticulocytes. DNA strand breaking activity of the compound at pH 7.4 increased with the increasing dose of the compound and with the increasing incubation time. The breaking activity was inhibited in the presence of superoxide dismutase, catalase, hydroxyl radical scavengers, spin trapping agents, thiol compounds and metal chelators, and also by removal of dissolved oxygen from the incubation mixture. Addition of Fe(III) ion to the incubation mixture enhanced the breaking activity. Incubation of DMHF with 5,5-dimethyl-1-pyrroline N-oxide (DMPO) gave electron spin resonance signals characteristic to DMPO-OH adduct, indicating generation of hydroxyl radical. It was found that DMHF generated hydroxyl radical with an aid of a trace amount of metal ions, and induced DNA strand breaking. Mutagenicity and induction of micronucleated reticulocytes by DMHF may be caused as a result of DNA modification via hydroxyl radical.

The toxic activities of Ga-Sn alloy (Adlloy-OH) in experimental rats, its relations to the nutritional condition and dental caries development, were studied for three months. Adlloy, 0.3 g or 3 g per body weight (kg), was fed orally with the basal diet consisting of casein, sucrose, bean oil, mineral, and vitamin mixtures. Biochemical assays of serum was carried out for total protein, albumin, calcium, inorganic phosphate, glucose, urea, creatine, alkaline phosphatase, GOT, and GPT. There was no convincing evidence of toxic effects on growth and biochemical data by the oral feeding of Addloy-OH.

The biological effects of adhesive resins were studied by an organ culture method using chick embryo femurs, of which usefulness was investigated to evaluate the biocompatibility of biomaterials. Superbond C & B and Panavia EX were processed to form test pieces of 0.35 mm in diameter and 2 mm in length. The test piece was inserted into the distal epiphysis of the femur, which was cultured at 37 degrees C for 7 days. The biomaterials were evaluated by relative growth rate, relative wet/dry weight ratio (W/D) and histological examination. The femurs with insertion of Superbond C & B or Panavia EX did not show growth inhibition, but W/D of Panavia EX was significantly higher than that of control. Histologically, undifferentiated cartilage cells and immature cartilage matrix were observed in the tissue adjacent to Panavia EX. These results suggested that Panavia EX had a slightly toxic effect on the chick embryo femur.

This study investigated the adhesive strength of cyanoacrylate dental adhesive, 'F.H cement' after being thermal-cycled in order to certify its stability in water. The adhesive strength was compared using Zinc phosphate cement, Glass ionomer cement, Dental adhesive resin and F.H cement when an ivory die and a cast crown were adhered by these different cements. Results of the study indicated the following: 1. The adhesive strength after being thermal-cycled indicated that F.H cement had a greater strength than the other cements (Zinc phosphate cement and Glass ionomer cement) and was equal to that of the Dental adhesive resin. 2. F.H cement was also found to be the strongest in adhesive strength when different tapers were used.

Macro- and microscopic studies were made of an interfacial microstructure which developed between a bifunctional monomer and a PMMA rod (or beads) during polymerization. The microstructure consisted of a white band and a blue transparent zone.