scholarly journals Cryptococcus neoformans – New Science for Discovering Melanin Modifiers

2018 ◽  
pp. 1-4
Author(s):  
R. Soundharya ◽  
V. Aruna ◽  
G. V. Amruthavalli ◽  
R. Gayathri
Keyword(s):  
Cryptococcus Neoformans ◽  
Mechanism Of Action ◽  
Living Cell ◽  
Cell Model ◽  
Cost Effective ◽  
Time Intervals ◽  
New Science ◽  
Biological Tool ◽  
Minimal Media ◽  
Presence And Absence

Aim: The present study was taken up to establish the effect of niacinamide on phenoloxidase lead melanogenesis and to prove the reliability of C. neoformans based screening methodology. Methods: The organism was grown in the Minimal media in presence and absence of L- DOPA and Niacinamide and checked for its pigment producing ability at different time intervals. Results: Niacinamide did not affect the pigmentation in Cryptococcus neoformans in the absence or presence of L-Dopa. Conclusion: Cryptococcus neoformans as a biological tool for studying the mechanism of action of various melanin promoters/ inhibitors. The present study highlights the importance and usefulness of Cryptococcus neoformans based screening invention as it is cost effective rapid and ‘living cell model’.

scholarly journals Address of the President Sir Robert Robinson, at the anniversary meeting, 1 December 1947

1947 ◽  
Vol 135 (878) ◽  
Keyword(s):  
Living Cell ◽  
Royal Society ◽  
Scientific Discipline ◽  
New Science ◽  
Scientific World ◽  
Intimate Association ◽  
Scientific Life

The names that have just been recounted include those of many outstanding personalities in the scientific world and it would not be fitting to attempt even brief appreciations of their manifold services on this occasion. An exception must, however, be made when we mourn such giants as two of the deceased Fellows. Sir Frederick Gowland Hopkins, O. M., was elected a Fellow of the Society in 1905; he delivered the Croonian Lecture in 1915, was Royal Medallist in 1918 and Copley Medallist in 1926. He was President of the Society from 1930 to 1935. Such are the bare facts, and though we are proud of his intimate association with the Royal Society, we do not now think of a Lecturer, a Medallist, or even of a President. Our memory dwells rather on the lovable qualities and magnanimous spirit of a devoted teacher and leader, and on the influence of his generous help to others as well as of his personal achievements during almost seventy years of scientific life. He was early imbued with the conviction that the chemistry of the living cell was his subject, that it was not only of transcendent importance, but also that it was ripe for development. He dedicated himself to the quest and embarked with enthusiasm on a pioneering voyage of discovery. The outcome of his courage and industry was the foundation of a new scientific discipline, if not of a new science. He was the father of modern schools of biochemistry and was the greatest biochemist of his generation.

scholarly journals Evaluation of the Dislodgement Resistance of a New Pozzolan-Based Cement (EndoSeal MTA) Compared to ProRoot MTA and Biodentine in the Presence and Absence of Blood

Scanning ◽  
2019 ◽  
Vol 2019 ◽  
pp. 1-6 ◽  
Author(s):  
Alireza Adl ◽  
Nooshin Sadat Shojaee ◽  
Negar Pourhatami
Keyword(s):  
Bond Strength ◽  
Testing Machine ◽  
Time Intervals ◽  
Failure Patterns ◽  
Tukey Test ◽  
Universal Testing ◽  
Presence And Absence ◽  
Type Of Failure ◽  
Push Out

Introduction. This in vitro study investigated the dislodgement resistance of EndoSeal MTA, a new pozzolan-containing calcium silicate-based material, in comparison with ProRoot MTA and Biodentine in the presence and absence of contamination with blood. Methods. Standard furcal perforations were created in 180 human mandibular first molars. The teeth were randomly allocated to 12 groups of 15 each. ProRoot MTA, Biodentine, and EndoSeal MTA were used to repair the perforations. In half of the samples, the walls of the perforated areas were contaminated with blood, whereas saline was injected into the other half. A push-out test was performed using a universal testing machine after 24 hours or 7 days. To evaluate failure patterns, the samples were split into half and were examined under a stereomicroscope at a 20x magnification. Data were analyzed using three-way analysis of variance, Tukey test, and Student’s t-test. Results. At both time intervals and in the presence and absence of contamination with blood, ProRoot MTA and Biodentine had significantly higher retention values than EndoSeal MTA (p<0.001). Contamination with blood had no effect on EndoSeal MTA; however, it negatively affected the dislodgement resistance of Biodentine at 24 hours and ProRoot MTA at both time intervals (p<0.05). Time significantly affected only the bond strength of the uncontaminated groups (p>0.001). The most common type of failure was mixed for ProRoot MTA and Biodentine, whereas it was cohesive for EndoSeal MTA. Conclusions. ProRoot MTA and Biodentine showed higher values of bond strength than EndoSeal MTA and may thus be better options for the repair of root perforations.

scholarly journals Sterol composition of Cryptococcus neoformans in the presence and absence of fluconazole.

1994 ◽  
Vol 38 (9) ◽  
pp. 2029-2033 ◽  
Author(s):  
M A Ghannoum ◽  
B J Spellberg ◽  
A S Ibrahim ◽  
J A Ritchie ◽  
B Currie ◽  
...  
Keyword(s):  
Cryptococcus Neoformans ◽  
Sterol Composition ◽  
Presence And Absence

scholarly journals An Integrative Resource for Network-Based Investigation of COVID-19 Combinatorial Drug Repositioning and Mechanism of Action

2020 ◽  
Author(s):  
AKM Azad ◽  
Shadma Fatima ◽  
Fatemeh Vafaee
Keyword(s):  
Combination Therapy ◽  
Mechanism Of Action ◽  
Drug Repositioning ◽  
Clinical Investigation ◽  
Cost Effective ◽  
Similarity Score ◽  
Drug Combinations ◽  
Huge Number ◽  
Web Based ◽  
Therapeutic Development

<p>Repurposing of the existing medications has become the mainstream focus of anti-COVID-19 drug discovery as it offers rapid and cost-effective solutions for therapeutic development. However, there is still a great deal to enhance efficacy of repurposing therapeutic options through combination therapy, in which promising drugs with varying mechanisms of action are administered together. Nonetheless, our ability to identify and validate effective combinations is limited due to the huge number of possible drug pairs. Yet, there is no available resource which can systematically guide to identify or choose the effective individual drugs or best possible synergistic drug combinations for the treatment of SARS-CoV-2 infection. To address this resource gap, we developed a web-based platform that displays the network-based mechanism of action of drug combinations, thus simultaneously giving a visual of the cellular interactome involved in the mode of action of the chosen drugs. The platform allows the freedom to choose two or more drug combinations and provides the options to investigate network-based efficacy of drug combinations and understand the similarity score, primary indications, and contraindications of using these drugs combinations. In a nutshell, the platform (accessible via: <a href="http://vafaeelab.com/COVID19_repositioning.html">http://vafaeelab.com/COVID19_repositioning.html</a>) is of the first of its type which provides a systematic approach for pre-clinical investigation of combination therapy for treating COVID-19 on the fingertips of the clinicians or researchers.</p>

scholarly journals α-lipoic acid has the potential to normalize copper metabolism, which is dysregulated in Alzheimer′s disease

2021 ◽  
Author(s):  
Kristel Metsla ◽  
Sigrid Kirss ◽  
Katrina Laks ◽  
Gertrud Sildnik ◽  
Mari Palgi ◽  
...  
Keyword(s):  
Lipoic Acid ◽  
Neurodegenerative Disorder ◽  
Cell Model ◽  
Neuronal Cell ◽  
Copper Metabolism ◽  
Cost Effective ◽  
Intracellular Space ◽  
Drug Candidates ◽  
Treatment And Prevention ◽  
Intracellular Copper

Alzheimer′s disease (AD) is an age-dependent progressive neurodegenerative disorder and the most common cause of dementia. The treatment and prevention of AD present immense yet unmet needs. One of the hallmarks of AD is the formation of extracellular amyloid plaques in the brain, composed of amyloid-beta (Aβ) peptides. Multiple amyloid-targeting drug candidates have recently failed in clinical trials, which creates the necessity to focus also on alternative therapeutic strategies. One factor contributing to the development of AD is dysregulated copper metabolism, reflected in the intracellular copper deficit and excess extracellular copper levels. In the current study, we follow the widely accepted hypothesis that the normalization of copper metabolism leads to the prevention or slowing of the disease and searched for new copper-regulating ligands. We demonstrate that the natural intracellular copper chelator, α-lipoic acid (LA) translocates copper from extracellular to intracellular space in a SH-SY5Y-based neuronal cell model, and is thus suitable to alleviate the intracellular copper deficit characteristic of AD neurons. Furthermore, we show that supplementation with LA protects the Drosophila melanogaster model of AD from developing AD phenotype, reflecting in decreased locomotor activity. Collectively, these results provide evidence that LA has the potential to normalize copper metabolism in AD and supports the hypothesis that LA supplementation may serve as a promising cost-effective method for the prevention and/or treatment of AD.

DIFFERENCES IN PEPTIDE MAPS OF a POLYMERS FROM FIBRIN PRODUCED IN THE PRESENCE AND ABSENCE OF ERYTHROCYTES

1987 ◽  
Author(s):  
M Hoser ◽  
G F Savidge
Keyword(s):  
Proteolytic Cleavage ◽  
Clot Formation ◽  
Plasma Samples ◽  
Polyacrylamide Gels ◽  
Time Intervals ◽  
Α Chain ◽  
Presence And Absence ◽  
Kinetics Of ◽  
Peptide Maps

α chain polymerisation during clot formation is accelerated in the presence of erythrocytes. This effect is abrogated if the erythrocytes are obtained from patients with various haemoglo-binopathies. Enzyme digests of the α polymers produced in the presence or absence of erythrocytes were prepared to further define any differences between them.Clots were produced from citrate/EACA plasma samples or plasma/erythrocyte mixtures by the addition of thrombin and calcium. After five hours, clots were washed iii 8 M urea until traces of haemoglobin were removed. After reduction and alkylation clots were dissolved in 0.5% SDS. a polymers were purified on sephacryl S-300 and protein concentrations were adjusted to 0.5 mg/ml. These were digested with S. Aureus V8 protease (150 mg/ml), papain (50 mg/ml) or chymotrypsin (100 mg/ml) at 37°C at sequential time intervals.After the addition of 2% SDS samples were analysed on 15% SDS polyacrylamide gels.In all cases digestion of a polymers from clots formed in the absence of erythrocytes took place more rapidly and contained peptide bands not apparent in other digests.The observations suggest that α polymers formed in the presence or absence of erythrocytes exhibit differing kinetics of response to proteolytic cleavage and indicate that erythrocytes may influence the primary and/or quartenary structure of the polymers studied.

scholarly journals Differentiated ovine tracheal epithelial cells support the colonisation of pathogenic and non-pathogenic strains of Mannheimia haemolytica

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Nicky O’Boyle ◽  
Catherine C. Berry ◽  
Robert L. Davies
Keyword(s):  
Cell Model ◽  
Bacterial Species ◽  
Cost Effective ◽  
Disease Status ◽  
Mannheimia Haemolytica ◽  
Cell Physiology ◽  
Time Points ◽  
Tracheal Epithelial Cells ◽  
Cell Responses ◽  
Tracheal Epithelial

Abstract Mannheimia haemolytica is the primary bacterial species associated with respiratory disease of ruminants. A lack of cost-effective, reproducible models for the study of M. haemolytica pathogenesis has hampered efforts to better understand the molecular interactions governing disease progression. We employed a highly optimised ovine tracheal epithelial cell model to assess the colonisation of various pathogenic and non-pathogenic M. haemolytica isolates of bovine and ovine origin. Comparison of single representative pathogenic and non-pathogenic ovine isolates over ten time-points by enumeration of tissue-associated bacteria, histology, immunofluorescence microscopy and scanning electron microscopy revealed temporal differences in adhesion, proliferation, bacterial cell physiology and host cell responses. Comparison of eight isolates of bovine and ovine origin at three key time-points (2 h, 48 h and 72 h), revealed that colonisation was not strictly pathogen or serotype specific, with isolates of serotype A1, A2, A6 and A12 being capable of colonising the cell layer regardless of host species or disease status of the host. A trend towards increased proliferative capacity by pathogenic ovine isolates was observed. These results indicate that the host-specific nature of M. haemolytica infection may result at least partially from the colonisation-related processes of adhesion, invasion and proliferation at the epithelial interface.

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