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Pharmaceutics Mar 2022Orodispersible films (ODFs) have been widely used in paediatric, geriatric and dysphagic patients due to ease of administration and precise and flexible dose...
Orodispersible films (ODFs) have been widely used in paediatric, geriatric and dysphagic patients due to ease of administration and precise and flexible dose adjustments. ODF fabrication has seen significant advancements with the move towards more technologically advanced production methods. The acceptability of ODFs is dependent upon film composition and process of formation, which affects disintegration, taste, texture and mouthfeel. There is currently a lack of testing to accurately assess ODFs for these important acceptability sensory perceptions. This study produced four ODFs formed of polyvinyl alcohol and sodium carboxymethylcellulose using 3D printing. These were assessed using three in vitro methods: Petri dish and oral cavity model (OCM) methods for disintegration and bio-tribology for disintegration and oral perception. Increasing polymer molecular weight (MW) exponentially increased disintegration time in the Petri dish and OCM methods. Higher MW films adhered to the OCM upper palate. Bio-tribology analysis showed that films of higher MW disintegrated quickest and had lower coefficient of friction, perhaps demonstrating good oral perception but also stickiness, with higher viscosity. These techniques, part of a toolbox, may enable formulators to design, test and reformulate ODFs that both disintegrate rapidly and may be better perceived when consumed, improving overall treatment acceptability.
PubMed: 35456566
DOI: 10.3390/pharmaceutics14040732 -
IMA Fungus 2019Traditionally, fungal growth dynamics were assessed manually, limiting the research to a few environmental conditions and/or fungal species. Fortunately, more automated...
Traditionally, fungal growth dynamics were assessed manually, limiting the research to a few environmental conditions and/or fungal species. Fortunately, more automated ways of measurement are gaining momentum due to the availability of cheap imaging and processing equipment and the development of dedicated image analysis algorithms. In this paper, we use image analysis to assess the impact of environmental conditions on the growth dynamics of two economically important fungal species, and . Sixteen environmental conditions combining four temperatures (15, 20, 25 and 30 °C) and four relative humidity (RH) conditions (65, 70, 75 and 80% RH) were tested. Fungal growth characteristics were extracted from images of the growing fungi, taken at regular points in time. Advanced time series analysis was applied to quantitatively compare the effect of the environmental conditions on these growth characteristics. The evolution of the mycelial area and the number of tips over time resulted in typical sigmoidal growth curves. Other growth characteristics such as the mean hyphal segment length did not vary significantly over time. Temperature and RH usually had a combined effect on the growth dynamics of the mycelial area and the number of tips. When defining optimal growth conditions for a fungus, it is therefore of primordial importance that the effect of temperature and RH is assessed simultaneously. At the most extreme conditions we tested, the mycelium most probably experienced water stress when developing over the inert Petri dish surface. An RH of 65% (independent of temperature) for and a temperature of 30 °C (independent of RH) for both and therefore always resulted in limited fungal growth, while the optimal growing conditions were at 20 °C and 75% RH and at 25 °C and 80% RH for and at 20 °C and 75% RH for . The method applied in this study offers an updated and broader alternative to classical and narrowly focused studies on fungal growth dynamics, and is well suited to efficiently assess the effect of environmental conditions on fungal growth.
PubMed: 32647616
DOI: 10.1186/s43008-019-0009-3 -
Evolutionary Applications Jan 2018Current natural populations face new interactions because of the re-emergence of ancient microbes and viruses. These risks come from the re-emergence of pathogens kept... (Review)
Review
Current natural populations face new interactions because of the re-emergence of ancient microbes and viruses. These risks come from the re-emergence of pathogens kept in laboratories or from pathogens that are retained in the permafrost, which become available upon thawing due to climate change. We here focus on the effects of such re-emergence in natural host populations based on evolutionary theory of virulence and long-term studies, which investigate host-pathogen adaptations. Pathogens tend to be locally and temporally adapted to their co-occurring hosts, but when pathogens from a different environment or different time enter the host community, the degree to which a new host-pathogen interaction is a threat will depend on the specific genotypic associations, the time lag between the host and the pathogen, and the interactions with native or recent host and pathogen species. Some insights can be obtained from long-term studies using a resurrection ecology approach. These long-term studies based on time-shift experiments are essential to obtain insight into the mechanisms underlying host-pathogen coevolution at several ecological and temporal scales. As past pathogens and their corresponding host(s) can differ in infectivity and susceptibility, strong reciprocal selective pressures can be induced by the pathogen. These strong selective pressures often result in an escalating arms race, but do not necessarily result in increased infectivity over time. Human health can also be impacted by these resurrected pathogens as the majority of emerging infectious diseases are zoonoses, which are infectious diseases originating from animal populations naturally transmitted to humans. The sanitary risk associated with pathogen emergence from different environments (spatial or temporal) depends on a combination of socioeconomic, environmental, and ecological factors that affect the virulence or the pathogenic potential of microbes and their ability to infect susceptible host populations.
PubMed: 29302270
DOI: 10.1111/eva.12538 -
International Journal of Clinical... 2022The aim and objective of this study is to compare the efficacy of four various approaches of sterilizing endodontic hand files Autoclave, Glass-bead sterilizer,...
AIM AND OBJECTIVE
The aim and objective of this study is to compare the efficacy of four various approaches of sterilizing endodontic hand files Autoclave, Glass-bead sterilizer, Glutaraldehyde solution, and Diode laser.
MATERIALS AND METHODS
Fifty-two k-files of size #25 and length 21 mm were taken for the study. All the 52 files were presterilized in an endodontic instrument box autoclave. spore suspension was prepared and all the presterilized files were contaminated with stearothermophilus spore suspension in a sterile Petri dish under vacuum hood safety. Later, the test files were randomly divided into four groups of 13 each and subjected to four different methods of sterilization- Autoclave, Glass-bead sterilizer, Glutaraldehyde solution, and Diode laser. Files were then be placed in thioglycollate media containing test tubes and incubated in an incubator at 55°C and checked for turbidity at 3 days and 21 days.
RESULT
The result revealed that there was no Turbidity present in test tubes on both the 3rd and 21st day for autoclave. In all the remaining sterilization procedures there was some amount of turbidity present. In terms of sterilization provided autoclave provides complete sterilization and glutaraldehyde solution is the least effective.The specificity of was then confirmed with a sugar test viz., starch hydrolysis test which gave a positive result confirming the presence of .
CONCLUSION
We can conclude that autoclave is the perfect process of sterilization providing 100% sterility and although Glass-bead didn't provide 100% sterility, it can be used as an alternative if autoclave is not available.
HOW TO CITE THIS ARTICLE
Ameer B, Khatib MS, Peerzade SM, Comparing Sterilization of Endodontic Hand Files by Four Different Methods: An Study. Int J Clin Pediatr Dent 2022;15(2):149-152.
PubMed: 37457218
DOI: 10.5005/jp-journals-10005-2346 -
Vaccine Jan 2017Malaria in pregnancy is associated with significant morbidity in pregnant women and their offspring. Plasmodium falciparum infected erythrocytes (IE) express VAR2CSA... (Comparative Study)
Comparative Study
BACKGROUND
Malaria in pregnancy is associated with significant morbidity in pregnant women and their offspring. Plasmodium falciparum infected erythrocytes (IE) express VAR2CSA that mediates binding to chondroitin sulphate A (CSA) in the placenta. Two VAR2CSA-based vaccines for placental malaria are in clinical development. The purpose of this study was to evaluate the robustness and comparability of binding inhibition assays used in the clinical development of placental malaria vaccines.
METHODS
The ability of sera from animals immunised with different VAR2CSA constructs to inhibit IE binding to CSA was investigated in three in vitro assays using 96-well plates, petri dishes, capillary flow and an ex vivo placental perfusion assay.
RESULTS
The inter-assay variation was not uniform between assays and ranged from above ten-fold in the flow assay to two-fold in the perfusion assay. The intra-assay variation was highest in the petri dish assay. A positive correlation between IE binding avidity and the level of binding after antibody inhibition in the petri dish assay indicate that high avidity IE binding is more difficult to inhibit. The highest binding inhibition sensitivity was found in the 96-well and petri dish assays compared to the flow and perfusion assays where binding inhibition required higher antibody titers.
CONCLUSIONS
The inhibitory capacity of antibodies is not easily translated between assays and the high sensitivity of the 96-well and petri dish assays stresses the need for comparing serial dilutions of serum. Furthermore, IE binding avidity must be in the same range when comparing data from different days. There was an overall concordance in the capacity of antibody-mediated inhibition, when comparing the in vitro assays with the perfusion assay, which more closely represents in vivo conditions. Importantly the ID1-ID2a protein in a liposomal formulation, currently in a phase I trial, effectively induced antibodies that inhibited IE adhesion in placental tissue.
Topics: Animals; Antibodies, Protozoan; Antigens, Protozoan; Cell Adhesion; Chondroitin Sulfates; Cytological Techniques; Drug Discovery; Erythrocytes; Female; Malaria Vaccines; Malaria, Falciparum; Mice, Inbred C57BL; Placenta Diseases; Pregnancy; Rabbits; Rats, Wistar; Reproducibility of Results
PubMed: 28012775
DOI: 10.1016/j.vaccine.2016.12.028 -
Biomedical Microdevices May 2022Three-dimensional cell agglomerates are broadly useful in tissue engineering and drug testing. We report a well-free method to form large (1.4-mm) multicellular clusters...
Three-dimensional cell agglomerates are broadly useful in tissue engineering and drug testing. We report a well-free method to form large (1.4-mm) multicellular clusters using 100-MHz surface acoustic waves (SAW) without direct contact with the media or cells. A fluid couplant is used to transform the SAW into acoustic streaming in the cell-laden media held in a petri dish. The couplant transmits longitudinal sound waves, forming a Lamb wave in the petri dish that, in turn, produces longitudinal sound in the media. Due to recirculation, human embryonic kidney (HEK293) cells in the dish are carried to the center of the coupling location, forming a cluster in less than 10 min. A few minutes later, these clusters may then be translated and merged to form large agglomerations, and even repeatedly folded to produce a roughly spherical shape of over 1.4 mm in diameter for incubation-without damaging the existing intercellular bonds. Calcium ion signaling through these clusters and confocal images of multiprotein junctional complexes suggest a continuous tissue construct: intercellular communication. They may be formed at will, and the method is feasibly useful for formation of numerous agglomerates in a single petri dish.
Topics: Acoustics; Animals; Cell Communication; Culture Media; HEK293 Cells; Humans; Sheep; Sound
PubMed: 35596837
DOI: 10.1007/s10544-022-00617-z -
Medical Mycology Journal 2021We postulated that disinfection of viable Trichophyton species in shoes would help reduce the number of patients with tinea pedis in Japan and that this might be...
We postulated that disinfection of viable Trichophyton species in shoes would help reduce the number of patients with tinea pedis in Japan and that this might be accomplished safely using volatile components of essential oils. As vapor of lemongrass (Cymbopogon citratus) oil and citral have strong antimicrobial activities against Trichophyton, we examined the conditions under which lemongrass oil or citral show optimal antimicrobial activity in shoes. First, we investigated whether or not a strong antimicrobial effect could be obtained by combining with terpene aldehydes or aromatic aldehydes. When combined with citral, perillaldehyde showed superior antimicrobial activity to citronellal, cinnamaldehyde, cuminaldehyde, hydroxycitronellal, and vanillin. The combined effects of citral and perillaldehyde against Trichophyton mentagrophytes, Bacillus subtilis, and Candida albicans as volatile components dotted on filter paper placed away from the petri dish inoculated with fungi or bacteria were examined. Citral (2.5 mg/mL) and perillaldehyde (2.5 mg/mL) showed a greater inhibitory effect on growth of C. albicans than either solution alone in the aromatogram (disc diffusion) descent method (fractional inhibitory concentration [FIC] index of 0.58). Citral (2.5 mg/mL) and perillaldehyde (1.25 mg/mL) vapors in a closed box synergistically inhibited growth of B. subtilis and T. mentagrophytes (FIC indexes of 0.5 and 0.38, respectively). These results suggested that this combination would be safe and useful for disinfection of shoes.
Topics: Anti-Infective Agents; Cymbopogon; Humans; Oils, Volatile; Perilla; Trichophyton
PubMed: 34853254
DOI: 10.3314/mmj.21-00011 -
Gels (Basel, Switzerland) May 2023Macroscopic spatial patterns were formed in calcium alginate gels when a drop of a calcium nitrate solution was placed on the center of a sodium alginate solution on a...
Macroscopic spatial patterns were formed in calcium alginate gels when a drop of a calcium nitrate solution was placed on the center of a sodium alginate solution on a petri dish. These patterns have been classified into two groups. One is multi-concentric rings consisting of alternating cloudy and transparent areas observed around the center of petri dishes. The other is streaks extending to the edge of the petri dish, which are formed to surround the concentric bands between the concentric bands and the petri dish edge. We have attempted to understand the origins of the pattern formations using the properties of phase separation and gelation. The distance between two adjacent concentric rings was roughly proportional to the distance from where the calcium nitrate solution was dropped. The proportional factor increased exponentially for the inverse of the absolute temperature of the preparation. The also depended on the concentration of alginate. The pattern characteristics in the concentric pattern agreed with those in the Liesegang pattern. The paths of radial streaks were disturbed at high temperatures. The length of these streaks shortened with increasing alginate concentration. The characteristics of the streaks were similar to those of crack patterns resulting from inhomogeneous shrinkage during drying.
PubMed: 37367115
DOI: 10.3390/gels9060444 -
Biomicrofluidics Jan 2021Many wound-healing assays are used in cell biology and biomedicine; they are often labor intensive and/or require specialized and costly equipment. We describe a...
Many wound-healing assays are used in cell biology and biomedicine; they are often labor intensive and/or require specialized and costly equipment. We describe a contactless method to create wounds with any imaginable 2D pattern in cell monolayers using the micro-jets of either media or an immiscible and biocompatible fluorocarbon (i.e., FC40). We also combine this with another method that allows automation and multiplexing using standard Petri dishes. A dish is filled with a thin film of media overlaid with FC40, and the two liquids are reshaped into an array of microchambers within minutes. Each chamber in such a grid is isolated from others by the fluid walls of FC40. Cells are now added, allowed to grow into a monolayer, and wounds are created using the microjets; then, healing is monitored by microscopy. As arrays of chambers can be made using media and Petri dishes familiar to biologists, and as dishes fit seamlessly into their incubators, microscopes, and workflows, we anticipate that this assay will find wide application in wound healing.
PubMed: 33598064
DOI: 10.1063/5.0043312 -
PloS One 2022This study presents novel biocompatible Polydimethylsiloxane (PDMS)-based micromechanical tweezers (μTweezers) capable of the stiffness characterization and...
This study presents novel biocompatible Polydimethylsiloxane (PDMS)-based micromechanical tweezers (μTweezers) capable of the stiffness characterization and manipulation of hydrogel-based organoids. The system showed great potential for complementing established mechanical characterization methods such as Atomic Force Microscopy (AFM), parallel plate compression (PPC), and nanoindentation, while significantly reducing the volume of valuable hydrogels used for testing. We achieved a volume reduction of ~0.22 μl/sample using the μTweezers vs. ~157 μl/sample using the PPC, while targeting high-throughput measurement of widely adopted micro-mesoscale (a few hundred μm-1500 μm) 3D cell cultures. The μTweezers applied and measured nano-millinewton forces through cantilever' deflection with high linearity and tunability for different applications; the assembly is compatible with typical inverted optical microscopes and fit on standard tissue culture Petri dishes, allowing mechanical compression characterization of arrayed 3D hydrogel-based organoids in a high throughput manner. The average achievable output per group was 40 tests per hour, where 20 organoids and 20 reference images in one 35 mm petri dish were tested, illustrating efficient productivity to match the increasing demand on 3D organoids' applications. The changes in stiffness of collagen I hydrogel organoids in four conditions were measured, with ovarian cancer cells (SKOV3) or without (control). The Young's modulus of the control group (Control-day 0, E = 407± 146, n = 4) measured by PPC was used as a reference modulus, where the relative elastic compressive modulus of the other groups based on the stiffness measurements was also calculated (control-day 0, E = 407 Pa), (SKOV3-day 0, E = 318 Pa), (control-day 5, E = 528 Pa), and (SKOV3-day 5, E = 376 Pa). The SKOV3-embedded hydrogel-based organoids had more shrinkage and lowered moduli on day 0 and day 5 than controls, consistently, while SKOV3 embedded organoids increased in stiffness in a similar trend to the collagen I control from day 0 to day 5. The proposed method can contribute to the biomedical, biochemical, and regenerative engineering fields, where bulk mechanical characterization is of interest. The μTweezers will also provide attractive design and application concepts to soft membrane-micro 3D robotics, sensors, and actuators.
Topics: Cell Culture Techniques; Cell Line, Tumor; Female; Humans; Hydrogels; Middle Aged; Organoids; Stress, Mechanical
PubMed: 35073389
DOI: 10.1371/journal.pone.0262950