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Fulltext Suppression of non-Albicans candida species (NAC) biofilm formation by probiotic Streptococcus salivarius

Sharmeen Nellisa Soffian, Nurul Alia Risma Rismayuddin, Munirah Mokhtar, Mohd Hafiz Arzmi

Malaysian Journal of Medicine and Health Sciences, 2019;15(108):41-41.
MyJurnal

Introduction:Candida spp. are most common opportunistic pathogenic yeast that inhabit human oral cavity, epider-mis, gastrointestinal tract, and vagina leading to candidiasis. The transition of this yeast from commensal to potent pathogen is facilitated by numbers of virulence factors including biofilm formation. While most reports on candidi-asis are associated with formation Candida albicans biofilms, however, non-albicans Candida species prevalence is of growing concern. Recently, the use of probiotics as antifungal and antibiofilm has gained an increasing attention. As such, we aim to evaluate the inhibitory effect of monomicrobial and polymicrobial of Streptococcus salivariuson six strains of NAC namely Candida dubliniensis, Candida glabrata, Candida krusei, Candida lusitanaei, Candida parapsilosis and Candida tropicalis. Methods: Antifungal activity of S. salivarius on NAC species was performed using well diffusion method on Mueller Hinton Agar (MHA) and the diameter of inhibition zone were assessed. For formation of monomicrobial biofilm, standardized cell suspensions of NAC species (1 x 105 cells/ml) and probiotic Streptococcus salivarius (1 x 106 cells/ml) were grown in RPMI or nutrient broth media at 37°C for 72 h. Meanwhile to study polymicrobial biofilm of both NAC and S. salivarius, similar protocol was employed by inoculating both microorganisms with a similar cell density as in monomicrobial. Finally, biofilm formation was assessed through quantification of total biomass by crystal violet (CV) assay and the absorbance of adherent biofilm was measured in triplicate at 620nm. Results: Antifungal susceptibility testing of S. salivarius on all six NAC species discerned no zone of inhibition. Furthermore, our results showed variability of monomicrobial and polymicrobial biofilm biomass between NAC species and growth medium. All six polymicrobial NB-grown and RPMI-grown exhibited decreased of the biofilm formation. C. parapsilosis co-cultured with S. salivarius in NB medium had shown lowest biofilm bio-mass by 75.51+_1.34% while in RPMI medium, C. lusitanaei demonstrated with most reduced biofilm biomass by 67.03+_5.19. Conclusion: Our study elucidated the antagonistic relationship between Streptococcus salivarius and non-albicans Candida by supressing the growth of polymicrobial biofilm and pseudohyphae/hyphae of NAC species.

Matched MeSH terms: Suspensions
Fulltext Supramolecular Nested Microbeads as Building Blocks for Macroscopic Self-Healing Scaffolds

Yu Z, Liu J, Tan CSY, Scherman OA, Abell C

Angew Chem Int Ed Engl, 2018 03 12;57(12):3079-3083.
PMID: 29377541 DOI: 10.1002/anie.201711522

The ability to construct self-healing scaffolds that are injectable and capable of forming a designed morphology offers the possibility to engineer sustainable materials. Herein, we introduce supramolecular nested microbeads that can be used as building blocks to construct macroscopic self-healing scaffolds. The core-shell microbeads remain in an "inert" state owing to the isolation of a pair of complementary polymers in a form that can be stored as an aqueous suspension. An annealing process after injection effectively induces the re-construction of the microbead units, leading to supramolecular gelation in a preconfigured shape. The resulting macroscopic scaffold is dynamically stable, displaying self-recovery in a self-healing electronic conductor. This strategy of using the supramolecular assembled nested microbeads as building blocks represents an alternative to injectable hydrogel systems, and shows promise in the field of structural biomaterials and flexible electronics.

Matched MeSH terms: Suspensions
Fulltext Telescopic synthesis of cellulose nanofibrils with a stable dispersion of Fe(0) nanoparticles for synergistic removal of 5-fluorouracil

Sajab MS, Mohan D, Santanaraj J, Chia CH, Kaco H, Harun S, et al.

Sci Rep, 2019 08 12;9(1):11703.
PMID: 31406228 DOI: 10.1038/s41598-019-48274-2

The recognition of cellulose nanofibrils (CNF) in the past years as a high prospect material has been prominent, but the impractical cellulose extraction method from biomass remained as a technological barrier for industrial practice. In this study, the telescopic approach on the fractionation of lignin and cellulose was performed by organosolv extraction and catalytic oxidation from oil palm empty fruit bunch fibers. The integration of these techniques managed to synthesize CNF in a short time. Aside from the size, the zeta potential of CNF was measured at -41.9 mV, which allow higher stability of the cellulose in water suspension. The stability of CNF facilitated a better dispersion of Fe(0) nanoparticles with the average diameter size of 52.3-73.24 nm through the formulation of CNF/Fe(0). The total uptake capacity of CNF towards 5-fluorouracil was calculated at 0.123 mg/g. While the synergistic reactions of adsorption-oxidation were significantly improved the removal efficacy three to four times greater even at a high concentration of 5-fluorouracil. Alternatively, the sludge generation after the oxidation reaction was completely managed by the encapsulation of Fe(0) nanoparticles in regenerated cellulose.

Matched MeSH terms: Suspensions
Fulltext The effect of agitation speed on the co-deposition of Ni–SiC composite coating

Nur Azam Badarulzaman, Lee, Chung Heung, Ahmad Azmin Mohamad, Zainal Arifin Ahmad, Purwadaria, Sunara

Journal of Nuclear and Related Technologies, 2007;2007(1):83-86.
MyJurnal

Ni–SiC composite coatings were electrodeposited from a Watts-type bath containing 5 g/l SiC particles in suspension. The particles were dispersed with the aid of mechanical agitation at 75 rpm and 150 rpm. EDX analysis confirmed the existence of Ni and SiC in the coatings. The effects of agitation speed on hardness properties of the coatings were investigated. SEM results showed that lower agitation speed could improve the amount of co-deposited SiC particles and increase the hardness of the composite coatings. The bonding between the Ni metal matrix and the SiC ceramic particles was compact.

Matched MeSH terms: Suspensions
Fulltext The effect of pH on the survival of leptospires in water

Smith CE, Turner LH

Bull World Health Organ, 1961;24(1):35-43.
PMID: 20604084

One of the factors on which the incidence of leptospirosis is dependent is the survival time of shed leptospires in surface water or soil water, and this time is in turn affected by the acidity or alkalinity of the water. The authors have therefore studied the survival of four leptospiral serotypes in buffered distilled water at pH's ranging from 5.3 to 8.0. All survived longer in alkaline than in acid water, and significant differences between the serotypes were found in response to pH. Survival at pH's under 7.0 ranged from 10 to 117 days and at pH's over 7.0 from 21 to 152 days. Survival was also studied in aqueous extracts of soil samples from different areas in Malaya; no correlation was found between pH and survival time.It was also noted that in a group of Malayan ricefields a low incidence of leptospirosis in man was accompanied by a high infection rate among rodents, and when it was found that this phenomenon could not be explained by pH or salinity, attention was turned to the soil. Bentonite clay, similar to the montmorrillonite clay of the ricefields, was found to adsorb about half the leptospires in suspension. The authors recommend that field study of this laboratory observation be undertaken.

Matched MeSH terms: Suspensions
Thrombocyte counts in mice after the administration of papaya leaf suspension

Sathasivam K, Ramanathan S, Mansor SM, Haris MR, Wernsdorfer WH

Wien Klin Wochenschr, 2009 Oct;121 Suppl 3:19-22.
PMID: 19915811 DOI: 10.1007/s00508-009-1229-0

Following up a popular use of crude leaf preparations from Carica papaya for the treatment of dengue infections, a suspension of powdered Carica papaya leaves in palm oil has been investigated for its effect on thrombocyte counts in mice, administering by gavage 15 mg of powdered leaves per kg body weight to 5 mice. Equal numbers of animals received corresponding volumes of either palm oil alone or physiological saline solution. Thrombocyte counts before and at 1, 2, 4, 8, 10, 12, 24, 48 and 72 hours after dosing revealed significantly higher mean counts at 1, 2, 4, 8, 10 and 12 after dosing with the C. papaya leaf formulation as compared to the mean count at hour 0. There was only a non-significant rise of thrombocyte counts in the group having received saline solution, possibly the expression of a normal circadian rhythm in mice. The group having received palm oil only showed a protracted increase of platelet counts that was significant at hours 8 and 48 and obviously the result of a hitherto unknown stimulation of thrombocyte release. The results call for a dose-response investigation and for extending the studies to the isolation and identification of the C. papaya substances responsible for the release and/or production of thrombocytes.

Matched MeSH terms: Suspensions
TiO₂ nanoparticle transport and retention through saturated limestone porous media under various ionic strength conditions

Esfandyari Bayat A, Junin R, Derahman MN, Samad AA

Chemosphere, 2015 Sep;134:7-15.
PMID: 25889359 DOI: 10.1016/j.chemosphere.2015.03.052

The impact of ionic strength (from 0.003 to 500mM) and salt type (NaCl vs MgCl2) on transport and retention of titanium dioxide (TiO2) nanoparticles (NPs) in saturated limestone porous media was systematically studied. Vertical columns were packed with limestone grains. The NPs were introduced as a pulse suspended in aqueous solutions and breakthrough curves in the column outlet were generated using an ultraviolent-visible spectrometry. Presence of NaCl and MgCl2 in the suspensions were found to have a significant influence on the electrokinetic properties of the NP aggregates and limestone grains. In NaCl and MgCl2 solutions, the deposition rates of the TiO2-NP aggregates were enhanced with the increase in ionic strength, a trend consistent with traditional Derjaguin-Landau-Verwey-Overbeek (DLVO) theory. Furthermore, the NP aggregates retention increased in the porous media with ionic strength. The presence of salts also caused a considerable delay in the NPs breakthrough time. MgCl2 as compared to NaCl was found to be more effective agent for the deposition and retention of TiO2-NPs. The experimental results followed closely the general trends predicted by the filtration and DLVO calculations. Overall, it was found that TiO2-NP mobility in the limestone porous media depends on ionic strength and salt type.

Matched MeSH terms: Suspensions
Fulltext Transformation improvement with the Standardized Pressure Agrobacterium Infiltration Device (SPAID)

Mad' Atari MFB, Folta KM

BMC Res Notes, 2019 Mar 15;12(1):144.
PMID: 30876440 DOI: 10.1186/s13104-019-4117-3

OBJECTIVE: The treatment of plant tissue with Agrobacterium tumefaciens is often a critical first step to both stable and transient plant transformation. In both applications bacterial suspensions are oftentimes physically introduced into plant tissues using hand-driven pressure from a needleless syringe. While effective, this approach has several drawbacks that limit reproducibility. Pressure must be provided with the syringe perfectly perpendicular to the tissue surface. The researcher must also attempt to provide even and consistent pressure, both within and between experimental replicates. These factors mean that the procedures do not always translate well between research groups or biological replicates.
RESULTS: We have devised a method to introduce Agrobacterium suspensions into plant leaves with greater reproducibility. Using a decommissioned dissecting microscope as an armature, a syringe body with the bacterial suspension is mounted to the nosepiece. Gentle, even pressure is applied by rotating the focus knob. The treatment force is measured using a basic kitchen scale. The development of the Standardized Pressure Agrobacterium Infiltration Device (SPAID) provides a means to deliver consistent amounts of bacterial suspensions into plant tissues with the goal of increasing reproducibility between replicates and laboratories.

Matched MeSH terms: Suspensions
Transformation of cyclodextrin glucanotransferase (CGTase) from aqueous suspension to fine solid particles via electrospraying

Saallah S, Naim MN, Mokhtar MN, Abu Bakar NF, Gen M, Lenggoro IW

Enzyme Microb Technol, 2014 Oct;64-65:52-9.
PMID: 25152417 DOI: 10.1016/j.enzmictec.2014.06.002

In this study, the potential of electrohydrodynamic atomization or electrospraying to produce nanometer-order CGTase particles from aqueous suspension was demonstrated. CGTase enzyme was prepared in acetate buffer solution (1% v/v), followed by electrospraying in stable Taylor cone-jet mode. The deposits were collected on aluminium foil (collector) at variable distances from the tip of spraying needle, ranging from 10 to 25 cm. The Coulomb fission that occurs during electrospraying process successfully transformed the enzyme to the solid state without any functional group deterioration. The functional group verification was conducted by FTIR analysis. Comparison between the deposit and the as-received enzyme in dry state indicates almost identical spectra. By increasing the distance of the collector from the needle tip, the average particle size of the solidified enzyme was reduced from 200±117 nm to 75±34 nm. The average particle sizes produced from the droplet fission were in agreement with the scaling law models. Enzyme activity analysis showed that the enzyme retained its initial activity after the electrospraying process. The enzyme particles collected at the longest distance (25 cm) demonstrated the highest enzyme activity, which indicates that the activity was controlled by the enzyme particle size.

Matched MeSH terms: Suspensions
Fulltext Transport and retention of engineered Al2O3, TiO2, and SiO2 nanoparticles through various sedimentary rocks

Bayat AE, Junin R, Shamshirband S, Chong WT

Sci Rep, 2015;5:14264.
PMID: 26373598 DOI: 10.1038/srep14264

Engineered aluminum oxide (Al2O3), titanium dioxide (TiO2), and silicon dioxide (SiO2) nanoparticles (NPs) are utilized in a broad range of applications; causing noticeable quantities of these materials to be released into the environment. Issues of how and where these particles are distributed into the subsurface aquatic environment remain as major challenges for those in environmental engineering. In this study, transport and retention of Al2O3, TiO2, and SiO2 NPs through various saturated porous media were investigated. Vertical columns were packed with quartz-sand, limestone, and dolomite grains. The NPs were introduced as a pulse suspended in aqueous solutions and breakthrough curves in the column outlet were generated using an ultraviolet-visible spectrophotometer. It was found that Al2O3 and TiO2 NPs are easily transported through limestone and dolomite porous media whereas NPs recoveries were achieved two times higher than those found in the quartz-sand. The highest and lowest SiO2-NPs recoveries were also achieved from the quartz-sand and limestone columns, respectively. The experimental results closely replicated the general trends predicted by the filtration and DLVO calculations. Overall, NPs mobility through a porous medium was found to be strongly dependent on NP surface charge, NP suspension stability against deposition, and porous medium surface charge and roughness.

Matched MeSH terms: Suspensions