The ability of different compositions of calcium silicate and epoxy sealers to withstand gutta percha removal via in vitro pull-out testing.

OBJECTIVE: examination of the influence of chemical composition changes on the ability of sealers to withstand a pull-out test. MATERIALS AND METHODS: Fifty distal or palatal canals of extracted teeth were prepared by Dc Taper files. The teeth were divided into five groups: AH Plus, BJM RCS, Total Fill BC,AH Plus Bioceramic and a group with Gutta Percha with no sealer added. Ten days after obturation, each cone was subjected to the "pull-out test" with the Shimadzo Universal Testing Machine until it was torn or removed from the canal. A force to Stroke graph was generated and the maximum vertex of this graph was recorded. The number of times the cone was torn or removed was recorded. RESULTS: The amount of force needed to remove or rupture the cone was significantly higher in all sealer groups compared to the AH Plus Bioceramic group. The force needed for the AH Plus group was double that needed for the AH Plus Bioceramic group 4 (1.87 ± 0.53 N vs 0.93 ± 0.48 N, respectively, P < 0.001). All of the cones (n = 10) in the AH Plus Bio Ceramic Sealer group were removed in their entirety (P = 0.01 compared to each of the other groups). CONCLUSIONS: The addition of macromolecules to epoxy sealer does not change the material's ability to withstand the pull-out test. Decreasing the amount of tri- and di-calcium silicate compounds combined with increasing amounts of zirconium oxide in a Bioceramic sealer significantly decreased the material's ability to withstand the pull-out test.

Post-expiry stability of freeze-dried plasma under field conditions - Can shelf life be extended?

BACKGROUND: This prospective study evaluated the effect of routine, uncontrolled, Israeli field storage conditions on the safety and efficacy of Lyo-Plas N Freeze-Dried Plasma (FDP) at the end of the manufacturer's shelf life, and up to 24 months post expiry. Clotting factors V, VIII and XI, proteins S, C, fibrinogen, PTT, ATIII, VWF, and INR as well as TEG, DDM, residual moisture, pH, and sterility of FDP returned from field units after uncontrolled storage were evaluated. STUDY DESIGN AND METHODS: Parameters measured at the end of manufacturer shelf life, as well as 6, 12, 18, and 24 months after expiry, were compared to those of freshly supplied FDP doses. RESULTS: Changes were found when comparing freshly supplied FDP to all field-stored groups in INR, PT, PTT, pH, fibrinogen, and factor VIII. A significant change was also seen in Factor XI in the 12, 18, and 24 months post-expiry samples, Factor V and R in the 24 months post-expiry samples, MA in the 12, 24 months post-expiry group, and Protein C in the 18 months post-expiry group. An increase in the residual moisture from 0.90% in freshly supplied FDP to 1.35% in 24 months post-expiry FDP.; all p < .05. No growth was found in sterility analysis. CONCLUSION: Despite uncontrolled field storage conditions, the findings demonstrate that the safety and efficacy of FDP units, stored in uncontrolled conditions are only slightly affected, even beyond their expiration date. This information allows consideration of possibly extending the shelf life.

Stability of Diazepam Solution for Injection Following Long-Term Storage in an Ambient Temperature of the Mediterranean Climate.

PURPOSE: Diazepam is utilized as a convulsion antidote following nerve gas attacks. As an emergency medicine, it requires storage at ambient temperatures which often doesn't meet manufacturers' requirements, leading to an early invalidation of the product. Current work investigated this issue. METHODS: Long-term stability of diazepam ampoules for injection stored in an ambient temperature of the Mediterranean climate for ~10 years vs storage at room temperature was studied. RESULTS: Diazepam assay and pH remained within pharmacopeial specifications irrespective of storage conditions. A major degradation product 2-methylamino-5-chlorobenzophenone (MACB) showed a clear trend of accumulation as a function of storage time, exceeding the permitted limit at ~2 years, irrespective of storage conditions. A strong correlation between the discoloration of the solutions and the concentration of MACB was obtained. Intravenous administration of MACB to rats at doses ~2200-fold higher than permissible specification levels caused neither mortality nor any toxicological nor post-mortem findings. CONCLUSIONS: Regarding the parameters tested: diazepam assay, MACB assay, and pH, storing ampoules of diazepam solution for injection in field conditions of high temperatures of the Mediterranean climate did not cause accelerated degradation as compared to room temperature. These findings open an option for the usage of expired ampoules in special scenarios.

Freeze-dried plasma stability under prehospital field conditions.

BACKGROUND: This study evaluated the effect of routine, uncontrolled, Israeli field storage conditions on the stability and efficacy of Lyo-Plas N freeze-dried plasma (FDP). We evaluated clotting factors V, VIII, and XI; proteins S and C; fibrinogen; partial thromboplastin time (PTT); antithrombin III (ATIII); von Willebrand factor (VWF); and international normalized ratio (INR) in FDP stored at 4°C, 25°C, and 40°C for 6 and 12 months, as well as FDP returned from field units after uncontrolled storage for 15 months (manufacturer's shelf life). METHODS AND MATERIALS: After reconstitution, clotting factor levels were compared to those of freshly supplied FDP doses. RESULTS: At 4°C for 12 months, factor V decreased slightly. At 25°C, average fibrinogen and factor V content were significantly lower at both periods, and INR was higher after 12 months. At 40°C, all samples were out of normal range in at least one clotting factor after 6 or 12 months. After field storage for 15 months, fibrinogen, factors V and XI, PTT, and protein S were significantly decreased, and INR increased. However, these levels were still within laboratory norms. Statistically significant difference in clotting factors compared to laboratory normal range was found in INR (higher) and factor V (lower). CONCLUSIONS: Our data show minimal decreases in clotting factors in FDP after storage under field conditions, when compared to laboratory normal ranges. Along with the many advantages of FDP, this supports its use at the point of injury under battlefield conditions, despite uncontrolled storage environments. Under controlled storage conditions at 4°C, shelf life could possibly be extended, although further study is required.

In vitro toxicity of infusion sets depends on their composition, storage time and storage conditions.

Disposable medical devices release toxic leachables during their clinical use. Specifically, the individual parts of the infusion sets (the drip chamber, tube, flashball and injection site) are composed of numerous chemical compounds that can reach the patients' systemic circulation and induce local and systemic toxic effects. We aimed to reveal the relative in vitro toxicity of infusion sets from the leading vendors that are used in Israel, and to determine its dependence on their design and storage time/conditions. We found that leachates of the rubber parts were more toxic than those of the other parts of the infusion sets. The measured toxicity was affected by the experimental settings: the cells, medium composition, exposure duration, and the type of assay applied for toxicity assessment. We recommend to use the capillary endothelium cells for in vitro toxicity testing of the infusion sets, and refrain from the use of the MTT test which is insufficiently reliable, and can lead to artefacts and incorrect conclusions. Further investigation is needed to identify the toxic leachables from the individual parts of the infusion sets, and to reveal the risk of their toxicity during the clinical use of the infusion sets.

Toxicity assessment of extracts from infusion sets in cEND brain endothelial cells.

In vitro safety assessment of disposable medical devices, including infusion sets, is usually performed using L-929 mouse keratinocytes. However, cells of different origin (endothelial, lymphoid and myeloid cells) are also exposed to infusion sets' extractables during their clinical use. We studied whether the cEND mouse brain endothelial cells can be suitable for in vitro safety assessment of infusion sets. We analyzed infusion sets from different manufacturers that varied in design and storage time. cEND cells were incubated with extracts of individual parts of the infusion sets (tube, cup, latex), and relative toxicities were analyzed using MTT test, DCFH-DA-based analysis of reactive oxygen species formation, apoptosis and cell cycle analyses. We identified a pattern of yellowing of the infusion sets upon storage and revealed that it originated from the latex part. Extracts of the individual parts of the infusion sets, primarily of the latex, were toxic to the cEND cells leading to induction of apoptosis and cell death. We conclude that infusion sets release extractables that can be toxic to the endothelial cells of the patients that receive infusion. We suggest to use cEND cells for in vitro safety assessment of infusion sets and other medical devices that release extractables to the bloodstream.