Vermiculite as a culture substrate greatly improves the viability of frozen cultures of ectomycorrhizal basidiomycetes.

We assessed a new cryopreservation protocol that uses vermiculite as a culture substrate, called the vermiculite protocol (VP), by assessing the viability, recovery time of hyphae after revival, and colony diameter of cryosensitive ectomycorrhizal basidiomycete strains after storage for 2 weeks or 1 year in a vapour-phase liquid nitrogen tank. Twelve difficult-to-preserve strains of nine species (Amanita citrina, A. pantherina, A. rubescens, A. spissa, Kobayasia nipponica, Lactarius akahatsu, L. hatsudake, Sarcodon aspratus, and Tricholoma flavovirens) that did not achieve good revival after cryopreservation with our previous Homolka's perlite protocol and modified perlite protocol (MPP) experiments were used to assess the new methodology. Vermiculite and liquid medium were put into a cryotube and inoculated with an agar plug containing mycelia. The cryotube was cultured for various incubation times. After adequate mycelial growth, a mixture of cryoprotectants (5% dimethyl sulfoxide and 10% trehalose [5D10T] or 5% glycerol and 10% trehalose [5G10T]) was placed into the cryotube. The cryotube was frozen in a freezing container in a -80 °C freezer and then stored in vapour-phase liquid nitrogen. In the recovery test, 10 of 12 strains showed 100% revival after 2 weeks of storage in the 5G10T cryoprotectant, and all 12 strains showed 100% revival after 2 weeks of storage in the 5D10T cryoprotectant. Furthermore, all strains were viable after 1 year of storage in a vapour-phase liquid nitrogen tank. Thus, the VP is applicable to a wide range of ectomycorrhizal basidiomycete cultures, including highly cryosensitive strains.

Comparative Leachable Study of Glass Vials to Demonstrate the Impact of Low Fill Volume.

The pharmacopeia method for measuring the chemical durability of parenteral glass packaging is the hydrolytic resistance test in which the vial is filled to 90% of its brimful volume as described, for example, in USP <660>. However, an increasing number of innovative drugs are filled significantly below the nominal volume of the vial. As a consequence, the determined hydrolytic resistance is not representative of the concentrations of leached "glass" elements for low fill volumes. This is attributable to two main factors: Firstly, an increasing ratio of the wetted surface to volume and secondly an increased leaching tendency typically observed with borosilicate glass of the wall near bottom area, especially when standard manufacturing technology is applied.The extent of both contributing effects has been analyzed by determining the amounts of the representative leached "glass" elements, boron, sodium, and silicon, after vial storage for 24 weeks at 40°C with different fill volumes (0.5, 1.0, and 2.0 mL). The vials which have been investigated in this study have a nominal fill volume of 2 mL, were made from Type I class B borosilicate glass (Fiolax®) and from aluminosilicate glass and were filled with either purified water or a 15% KCl solution.The standard conversion process for tubing into vials was used for Fiolax vials (standard quality vials) and for aluminosilicate vials. In addition, an optimized conversion process (delamination controlled technology) was used to create low-fill quality Fiolax vials. The vial quality obtained from the two different converting technologies greatly influenced the concentrations of leached "glass" elements measured, especially when low fill volumes were used.LAY ABSTRACT: Borosilicate glass containers, because of their chemical inertness, excellent barrier properties, high transparency, and mechanical stability, have been successfully used for decades to package parenteral drug formulations. Nevertheless, Type I glass can be altered over a period of time when in contact with the drug formulation. The result of this interaction is even more pronounced for some new innovative drugs that are delivered to the patient in small dosages significantly below the nominal storage capacity of the glass vials. When the fill volume of the vials is reduced, the contribution of the bottom area to the wetted surface increases, resulting in a higher surface-to-volume ratio. Therefore, the concentrations of leached elements will be increased and this can cause problems for sensitive medical products. This effect is not usually observed with the standard test procedures described in the pharmacopeia because the vials are filled with a high volume to 90% brimful capacity (e.g., as described in USP <660>). In this study, the leachable behaviors of vials made of borosilicate and aluminosilicate glass were evaluated by using medium and low fill volumes with storage for 24 weeks at 40°C. The standard conversion process to manufacture a vial from glass tubing introduces volatile "glass" elements into the vial wall near the bottom area. This mechanism has been described and supported by time-of-flight secondary ion mass spectrometry (TOF-SIMS) measurements of the inner vial surface as reported by Rupertus et al. The diffusion mechanism of volatile components will increase the leaching propensity of the vial, especially for low fill volumes. However, innovative manufacturing techniques are able to avoid the diffusion of volatile elements into the wall near the bottom area. This is achieved by a specific process setup in combination with a suitable monitoring test during vial production, which gives a quantitative measure of the leaching tendency of the wall near the bottom area. Borosilicate glass vials manufactured with this setup (low-fill quality vials) showed a drastic reduction in leachables, especially with low fill volumes. Vials composed of a boron-free glass showed no advantages in terms of leaching behavior when compared with borosilicate glass vials in general.

Enhancing Patient Safety through the Use of a Pharmaceutical Glass Designed To Prevent Cracked Containers.

An essential role of packaging material for the storage and delivery of drug products is to provide adequate protection against contamination and loss of sterility. This is especially important for parenteral containers, as lack of sterility or contamination can result in serious adverse events including death. Nonetheless, cracked parenteral containers are an important source of container integrity failures for injectable drugs and pose a serious risk for patients. Despite significant investments in inspection technology, each year many injectable drugs are investigated and recalled for sterility risks associated with cracked borosilicate containers. Multiple studies and the many difficulties in detection of cracked containers suggest that the magnitude of the public health risk is even larger than the recall rate would suggest. Here we show that the root cause of cracked parenteral containers (low internal energy following annealing) is inherent to the glasses currently used for primary packaging of the majority of injectable drugs. We also describe a strengthened aluminosilicate glass that has been designed to prevent cracks in parenteral containers through the use of an engineered stress profile in the glass. Laboratory tests that simulate common filling line damage events show that the strengthened aluminosilicate glass is highly effective at preventing cracks. Significant safety benefits have been demonstrated in other industries from the use of special stress profiles in glass components to mitigate failure modes that may result in harm to humans. Those examples combined with the results described here suggest that a significant improvement in patient safety can be achieved through the use of strengthened aluminosilicate glass for parenteral containers.LAY ABSTRACT: Cracks are small cuts or gaps in a container which provide a pathway for liquid, gas, or microbes through a glass container. When these defects are introduced to conventional glass containers holding injectable medicines, the affected drug can pose serious risks to the patient receiving that medication. Specifically, the drug product may become less effective or even non-sterile, which could lead to bloodstream infections and, in some cases, death. This article presents a review of some previously documented cases of cracked glass containers that led to patient infections and deaths. Following a survey of common crack locations in glass vials, lab-based methods for replicating these cracks are presented. These methods are then used to compare the fracture response of vials made from conventional borosilicate glass and strengthened aluminosilicate glass. The results show that stable cracks are essentially prevented (at least 31 times less likely to occur) in the strengthened aluminosilicate glass containers (relative to conventional borosilicate glass). This improvement in safety is similar to improvements already engineered into other glass product designs by utilizing stored strain energy to mitigate certain failure modes.

Quality evaluation of processed clay soil samples.

INTRODUCTION: This study assessed the microbial quality of clay samples sold on two of the major Ghanaian markets. METHODS: The study was a cross-sectional assessing the evaluation of processed clay and effects it has on the nutrition of the consumers in the political capital town of Ghana. The items for the examination was processed clay soil samples. RESULTS: Staphylococcus spp and fecal coliforms including Klebsiella, Escherichia, and Shigella and Enterobacterspp were isolated from the clay samples. Samples from the Kaneshie market in Accra recorded the highest total viable counts 6.5 Log cfu/g and Staphylococcal count 5.8 Log cfu/g. For fecal coliforms, Madina market samples had the highest count 6.5 Log cfu/g and also recorded the highest levels of yeast and mould. For Koforidua, total viable count was highest in the samples from the Zongo market 6.3 Log cfu/g. Central market samples had the highest count of fecal coliforms 4.6 Log cfu/g and yeasts and moulds 6.5 Log cfu/g. "Small" market recorded the highest staphylococcal count 6.2 Log cfu/g. The water activity of the clay samples were low, and ranged between 0.65±0.01 and 0.66±0.00 for samples collected from Koforidua and Accra respectively. CONCLUSION: The clay samples were found to contain Klebsiella spp. Escherichia, Enterobacter, Shigella spp. staphylococcus spp., yeast and mould. These have health implications when consumed.

Folk pharmaceutical formulations in western Mediterranean: identification and safety of clays used in pelotherapy.

ETHNOPHARMACOLOGICAL RELEVANCE: Clays are naturally occurring ingredients of many natural health products, being included in most of ancient Mediterranean/European medical texts and currently used to prepare therapeutic hot-muds (peloids) in several thermal stations of the Mediterranean region. Clays are included in the formulation of peloids as vehicles of the mineral-medicinal water, to obtain inorganic gels with rheological and thermal properties suitable to be topically applied. Knowledge about formulations and preparation procedures of these traditional medicines has been orally transmitted since ancient times. Increasing recognition of the therapeutic utility of these traditional and natural health care substances make necessary a full ethnopharmaceutic research to ascertain those compositional characters that allow to establish quality attributes and corresponding requirements for these materials and products, including identity, purity, richness and safety. MATERIALS AND METHODS: Five clay samples (A, B, C, D and E) currently used in various spa centers of southern European/Mediterranean countries were studied. X-Ray diffraction (XRD) and X-ray fluorescence (XRF) data were used to asses sample identity and richness. Elemental impurities and microbiological contaminants were also determined and compared to normative limits. Particle size distribution was related to their safety as powder materials. RESULTS: Samples A, C, D and E were identified as "high purity clay", while sample B was identified as a mix of clay minerals and carbonates. The presence of carbonates in this sample could compromise its suitability for pelotherapy. The studied clays meet the main normative limits for metals impurities, with the exception of arsenic in sample A and nickel in sample B. The samples comply with the microbiological limits proposed by European legislation for medicinal products. According to the particle size of the studied samples, prevention and control of dust exposure must be considered. CONCLUSIONS: Despite their demonstrated longevity, the use of clays in traditional medicine formulations as peloids greatly requires comprehension of their identity and safety attributes. Continuity of these mineral substances as recognized health care ingredients oblige to conduct interdisciplinary research to know the features that sustain their traditional use in the preparation of medicines (ethnopharmaceutics).

Critical state of sand matrix soils.

The Critical State Soil Mechanic (CSSM) is a globally recognised framework while the critical states for sand and clay are both well established. Nevertheless, the development of the critical state of sand matrix soils is lacking. This paper discusses the development of critical state lines and corresponding critical state parameters for the investigated material, sand matrix soils using sand-kaolin mixtures. The output of this paper can be used as an interpretation framework for the research on liquefaction susceptibility of sand matrix soils in the future. The strain controlled triaxial test apparatus was used to provide the monotonic loading onto the reconstituted soil specimens. All tested soils were subjected to isotropic consolidation and sheared under undrained condition until critical state was ascertain. Based on the results of 32 test specimens, the critical state lines for eight different sand matrix soils were developed together with the corresponding values of critical state parameters, M, λ, and Γ. The range of the value of M, λ, and Γ is 0.803-0.998, 0.144-0.248, and 1.727-2.279, respectively. These values are comparable to the critical state parameters of river sand and kaolin clay. However, the relationship between fines percentages and these critical state parameters is too scattered to be correlated.

Levels of lead, arsenic, mercury and cadmium in clays for oral use on the Dutch market and estimation of associated risks.

Pregnant women in Africa, Asia and Suriname, and some immigrants in Western societies, traditionally consume clay products known by a variety of names such as mabele, calabash chalk, sikor and pimba. Furthermore, clay is used for health purposes in Western societies. Because certain clays can contain high levels of metals and metalloids, the aim of this study was to determine lead, arsenic, mercury and cadmium in clay products for oral use available on the Dutch market. Traditional clays originating from Africa (n = 10) and Suriname (n = 26), and health clays (n = 27) were sampled from 2004 up to and including 2012. Total metal and metalloid contents were measured by ICP-MS and showed maximum levels of lead, arsenic, mercury and cadmium of 99.7, 45.1, 2.2 and 0.75 mg kg⁻¹, respectively. In the absence of maximum limits for these type of clays, the potential exposure was estimated from the determined concentration, the estimated daily use level of the clays, and the estimated bioaccessibility of the different metals and arsenic. The intake estimates were compared with existing health-based guidance values. For lead, the use of 34 of the 36 traditional clays and two of the 27 health clays would result in intake levels exceeding the toxicological limit by up to 20-fold. Use of 15 of the 35 traditional clays and 11 of the 27 health clays would result in intake levels exceeding the toxicological limit for inorganic arsenic by up to 19-fold. Although limited bioaccessibility from the clay may limit the exposure and exceedance of the health-based guidance values, it was concluded that lead and arsenic intakes from some clay products could be of concern also because of their use by pregnant women and the potential developmental toxicity. As a result the use of these products, especially by pregnant women, should be discouraged.

[Methods for the improvement of clay quality for their therapeutic application].

The objective of this study was to develop a scientifically sound basis for obtaining composite materials for sanatorium-resort therapy by combining muds of different structure and composition with mineral waters from deposits of the Altai-Sayan tourist and recreational region. Numerous experiments with muds of the desired biochemical composition and mineral waters containing various biologically active substances yielded preparations that can be used for multiple purposes, such as activation metabolism of polymer phenolic compounds, energy metabolism, and self-cleaning processes. Mud and mineral water-based composites may contain other inorganic components, besides clays, accounting for their curative properties and capable of directed action, e.g. organic selenium compounds, glycosides, phenolic and carboxylic functional groups. The proposed technique provides a solid basis for designing materials the composition of which can be optimized as required for the treatment of concrete pathologies.

Dependence of radon emanation of red mud bauxite processing wastes on heat treatment.

Natural radioactivity content, radon emanation and some other physical characteristics of red mud were investigated, so that to identify the possibilities of the safe utilization of such material as a building material additive. Based on the radionuclide concentration, red mud is not permitted to be used directly as a building material, however, mixing of a maximum 20% red mud and 80% clay meets the requirements. The main aim of this work was to determine the dependence of the emanation factor of red mud firing temperature and some other parameters. The relevant experimental procedure was carried out in two different ways: without any additional material, and by adding a known amount of sawdust (5-35 wt%) then firing the sample at a given temperature (100-1000 degrees C). The average emanation factor of the untreated dry red mud was estimated to 20%, which decreased to about 5% at a certain heat treatment. Even lower values were found using semi-reductive atmosphere. It has been concluded that all emanation measurements results correlate well to the firing temperature, the specific surface and the pore volume.

IPS Empress: a standard of excellence.

For 10 years, clinicians have been able to provide patients with a proven aesthetic and functional restoration that exhibits wear-compatibility, durability, and marginal integrity. This leucite-reinforced, pressed ceramic (IPS Empress, Ivoclar Williams, Amherst, NY) presents to patients and dentists the option of a metal-free alternative which retains the functional advantages of a porcelain-fused-to-metal restoration. This article illustrates the importance of sound laboratory communication in the utilization of this restorative material, focusing upon three aspects: midline and incisal edge inclination, elimination of open gingival embrasures, and incisal edge translucency. Techniques are also presented in order to efficiently communicate details of each case presented to the laboratory.

A comparison of the marginal fit of In-Ceram, IPS Empress, and Procera crowns.

The in vitro marginal fit of three all-ceramic crown systems (In-Ceram, Procera, and IPS Empress) was compared. All crown systems were significantly different from each other at P = 0.05. In-Ceram exhibited the greatest marginal discrepancy (161 microns), followed by Procera (83 microns), and IPS Empress (63 microns). There were no significant differences among the various stages of the crown fabrication: core fabrication, porcelain veneering, and glazing. The facial and lingual margins exhibited significantly larger marginal discrepancies than the mesial and distal margins.

Creep of posterior dental composites.

The creep of microspecimens of posterior dental composites was studied using a torsional creep apparatus. Shear stresses were maintained for 3 h and recovery was followed for 50 h. Creep curves were obtained at 21, 37, and 50 degrees C and four torque levels. The effect of conditioning the specimens in water up to 8 weeks was studied. The posterior composites exhibited linear viscoelastic behavior at low deformations. They had higher shear moduli and greater resistance to creep than conventional and microfilled composites. In aging experiments, maximum shear moduli occurred when specimens were 48 h to 1 week old. Subsequent softening was attributed to water absorption. Residual strain was highest when the composites were stressed within 24 h of initiating polymerization. Residual strain was very low in specimens 48 h to 8 weeks of age.

[New measurement standard for cytofluorimetry]. / Novyi étalon dlia tsitofluorimetrii.

New phosphor crystals, on the basis of zeolit, activated by tin (Sn), appeared to be a very suitable permanent fluorescent test-object for setting up microscopes, intructing new users and for calibrating microfluorimeters. Their properties provide the control of conditions of various fluorescent experiments in both visible and ultraviolet regions. The crystal size may vary from 1 to 100 micron along the facet. Spectral, polarization and fading fluorescence characteristics of the new crystals are described.

The quantitative measurement of the opacity of aesthetic dental filling materials.

A method is described for measuring the opacity of anesthetic dental filling materials using a goniophotometer. Procedures are given for converting measured opacity values to those referred to a 70% reflectance background (C0.7 values) as required by existing specifications. The conversion is involved, and, since most available white surfaces have reflectance of about 80%, it is recommended that in future specifications opacity be recorded as C0.8 values. Opacity values for 28 materials are reported. It was found that the opacity of dental cement decreases for several days following preparation and that powder/liquid ratio has little effect, while pigmentation has a marked effect on opacity.

Physical characteristics of a new cleaning and polishing agent for use in a prophylaxips paste.

A prophylaxis composition containing a sodium-potassium aluminum silicate abrasive system was evaluated in the laboratory in comparison with several different commercial prophylaxis pastes. The in vitro data indicate that the new composition increases enamel polish and decreases abrasion characteristics without sacrificing cleaning efficacy when compared with the commercial products tested.