Search results for " Laboratory"

Can Hepatoma Cell Lines be Re-differentiated to be Used in Drug Metabolism Studies?

2013

Knowledge of metabolism, enzymes so far involved, and potential enzyme-inhibiting or enzyme-inducing properties of new compounds is a key issue in drug development. Primary cultured hepatocytes, cytochrome P450 (CYP)-engineered cells and hepatoma cell lines are currently being used for this purpose, but only primary cultures can produce a metabolic profile of a drug similar to that found in vivo and can respond to inducers. Because of their limited accessibility, alternatives to replace human hepatocytes are currently being explored, including the immortalisation of hepatocytes by using different strategies (i.e. SV40 T-large antigen, conditionally immortalised hepatocytes, transfection wi…

Synergistic Effect of Carfilzomib and Metformin in Vascular Plasticity; The Emerging Role of Autophagy

2019

Introduction: Carfilzomib (Cfz) correlates with a risk of reversible cardiotoxicity in 5-10% of multiple myeloma (MM) patients. We have recently shown that metformin (Met) has a prophylactic role against the Cfz-induced cardiotoxicity in vivo, through activation of AMPKα signaling (Blood 2019;133:710-23). However, the impact of Cfz on vascular function is obscure. Therefore, we sought to investigate: i) the acute, ii) the sub-chronic effect of Cfz on the vascular reactivity, iii) the effect of metformin co-administration on the vascular phenotype and iv) the impact of Cfz and Met co-administration on aged Human Aortic Smooth Muscle Cells (HAoSMCs). Methods: Forty male C57Bl/6 mice were assi…

High level of intrinsic phenotypic antimicrobial resistance in enterobacteria from terrestrial wildlife in Gabonese national parks.

2021

Data on the prevalence of antibiotic resistance in Enterobacteriaceae in African wildlife are still relatively limited. The aim of this study was to estimate the prevalence of phenotypic intrinsic and acquired antimicrobial resistance of enterobacteria from several species of terrestrial wild mammals in national parks of Gabon. Colony culture and isolation were done using MacConkey agar. Isolates were identified using the VITEK 2 and MALDI-TOF methods. Antibiotic susceptibility was analysed and interpreted according to the European Committee on Antimicrobial Susceptibility Testing guidelines. The preliminary test for ESBL-producing Enterobacteriaceae was performed by replicating enterobacte…

The selection of serum-independent PC12 cells for a more-reliable manganese cytotoxicity test.

2007

A major issue concerning the protocols of heavy metal cytotoxicity tests with PC12 cells was the hypothesis that serum in the culture medium might sequester the metal, thus altering the results obtained. However, serum withdrawal impairs the viability of PC12 cells themselves, thus impeding cytotoxicity testing in the absence of serum. In this study, we repeatedly selected undifferentiated, totally non-adherent PC12 cells in Petri dishes. Surprisingly, we discovered that these cells could survive and proliferate in serum-free medium. Moreover, features such as NGF-responsiveness, resazurin reduction potential, doubling rate, protein content, and basal caspase-3 enzyme activity, were equiva…

Host microbiota constantly control maturation and function of microglia in the CNS.

2015

As the tissue macrophages of the CNS, microglia are critically involved in diseases of the CNS. However, it remains unknown what controls their maturation and activation under homeostatic conditions. We observed substantial contributions of the host microbiota to microglia homeostasis, as germ-free (GF) mice displayed global defects in microglia with altered cell proportions and an immature phenotype, leading to impaired innate immune responses. Temporal eradication of host microbiota severely changed microglia properties. Limited microbiota complexity also resulted in defective microglia. In contrast, recolonization with a complex microbiota partially restored microglia features. We determ…

The Relationship between Gray Matter Quantitative MRI and Disability in Secondary Progressive Multiple Sclerosis

2016

Purpose: In secondary progressive Multiple Sclerosis (SPMS), global neurodegeneration as a driver of disability gains importance in comparison to focal inflammatory processes. However, clinical MRI does not visualize changes of tissue composition outside MS lesions. This quantitative MRI (qMRI) study investigated cortical and deep gray matter (GM) proton density (PD) values and T1 relaxation times to explore their potential to assess neuronal damage and its relationship to clinical disability in SPMS. Materials and Methods: 11 SPMS patients underwent quantitative T1 and PD mapping. Parameter values across the cerebral cortex and deep GM structures were compared with 11 healthy controls, and…

Dimethylsulfoxide as carrier in enzyme cytochemistry.

1971

Addition of dimethylsulfoxide (DMSO) to the incubation medium of succinate dehydrogenase in a concentration of 10% enhances the staining reaction in the hyphae of the fungus Cercosporella herpotrichoides after an incubation period of 15 min. Controls without DMSO remain unstained. DMSO causes a rapid penetration of the components of the medium through the mucilage that covers the hyphae.

Acute Toxicity Testing in Vitro and the Classification and Labelling of Chemicals

1996

Kinetics and equilibrium in insulin radioimmunoassay.

2002

The kinetics of insulin reaction has been studied with its specific antibody immobilized on the inner wall of the reaction tube; the radioimmunoanalytical determination of such a substance is based on the reaction. Independent variables were labelled and unlabelled insulin concentrations, temperature, viscosity, and the medium's ionic strength. Biexponential kinetics was found to be dependent on the concentrations fitted to the models discussed in the paper. The effect of temperature shows activation parameters similar to the viscous flow energy of water, which suggests that the reaction is diffusion-controlled. The results of the viscosity analysis points at the clearly negative influence …

Childhood Adversities and Adult Headache in Poland and Germany.

2015

Objective Various childhood adversities have been found to be associated with chronic pain in adulthood. However, associations were moderate in most studies, i.e. odds ratios (OR) were between one and two. Method An internet survey was performed in 508 Polish and 500 German subjects. A total of 19 childhood adversities were selected and their associations with headaches explored. Age, gender and country were included as potential confounders, as well as their two-way interaction with the risk factors. Results Two strong risk factors were identified. (1) A combined score for physical and emotional neglect showed an odds ratio (OR) of 2.78 (p < .002) to the frequency of headache in adulthood …