scholarly journals Cytotoxicity Induced by Tetracyclines via Protein Photooxidation

2015 ◽  
Vol 2015 ◽  
pp. 1-10 ◽  
Author(s):  
Domenico Fuoco
Keyword(s):  
Uv Light ◽  
Chemical Properties ◽  
Human Keratinocytes ◽  
Cellular Damage ◽  
Reactive Groups ◽  
A Cell ◽  
Set Up ◽  
Molecular Skeleton

Background. Bacterial ribosomes have been considered the principal targets of tetracyclines. Recently, new clinical data has shown how other biomacromolecules are involved in the cellular damage of bacteria. Researchers are now reconsidering the pharmacological classification of tetracyclines, not only based on their semisynthetic or synthetic generations but also following the new mechanisms of action that are progressively being discovered. Materials and Methods. The toxicity properties of seven tetracycline derivatives (tetracycline, oxytetracycline, demeclocycline, chlortetracycline, doxycycline, minocycline, and meclocycline) were investigated in vitro using a cell line of human keratinocytes. Cells were irradiated in the presence of tetracyclines for different durations and at three different intensities of light. The investigation of protein oxidation was set up using model proteins to quantify the formation of carbonyl groups. Results. After incubation and irradiation with UV light, the viability of keratinocytes was assessed with half the maximal inhibitory concentration for doxycycline, demeclocycline, chlortetracycline, and tetracycline. No phototoxicity was observed for oxytetracycline, meclocycline, and minocycline. Conclusions. This study provides evidence that tetracycline’s derivatives show different photobehaviour according to their chemical properties due to different reactive groups on the same molecular skeleton.

scholarly journals Positively Charged Lipid as Potential Tool to Influence the Fate of Ethosomes

2021 ◽  
Vol 11 (15) ◽  
pp. 7060
Author(s):  
Antonia Mancuso ◽  
Maria Chiara Cristiano ◽  
Massimo Fresta ◽  
Daniele Torella ◽  
Donatella Paolino
Keyword(s):  
Cell Model ◽  
Human Keratinocytes ◽  
Skin Delivery ◽  
Physico Chemical ◽  
Cell Mortality ◽  
Mean Size ◽  
A Cell ◽  
Negative Surface ◽  
Cytotoxic Studies

Ethosomes® are one of the main deformable vesicles proposed to overcome the stratum corneum. They are composed of lecithin, ethanol and water, resulting in round vesicles characterized by a narrow size distribution and a negative surface charge. Taking into account their efficiency to deliver drugs into deeper skin layers, the current study was designed to evaluate the influence of different lipids on the physico-chemical features of traditional ethosomes in the attempt to influence their fate. Three lipids (DOPE, DSPE and DOTAP) were used for the study, but only DOTAP conferred a net positive charge to ethosomes, maintaining a narrow mean size lower than 300 nm and a good polydispersity index. Stability and in vitro cytotoxic studies have been performed using Turbiscan Lab analysis and MTT dye exclusion assay, respectively. Data recorded demonstrated the good stability of modified ethosomes and a reasonable absence of cell mortality when applied to human keratinocytes, NCTC 2544, which are used as a cell model. Finally, the best formulations were selected to evaluate their ability to encapsulate drugs, through the use of model compounds. Cationic ethosomes encapsulated oil red o and rhodamine b in amounts comparable to those recorded from conventional ethosomes (over 50%). Results recorded from this study are encouraging as cationic ethosomes may open new opportunities for skin delivery.

scholarly journals Solubility, Permeability, and Dissolution Rate of Naftidrofuryl Oxalate Based on BCS Criteria

Pharmaceutics ◽  
2020 ◽  
Vol 12 (12) ◽  
pp. 1238
Author(s):  
Marta Kus-Slowinska ◽  
Monika Wrzaskowska ◽  
Izabela Ibragimow ◽  
Piotr Igor Czaklosz ◽  
Anna Olejnik ◽  
...  
Keyword(s):  
Dissolution Rate ◽  
Chemical Properties ◽  
Aqueous Solubility ◽  
Immediate Release ◽  
Drug Substances ◽  
High Dissolution Rate ◽  
Cerebral Diseases ◽  
Preliminary Classification

The Biopharmaceutics Classification System (BCS) was conceived to classify drug substances by their in vitro aqueous solubility and permeability properties. The essential activity of naftidrofuryl oxalate (NF) has been described as the inhibition of the serotonin receptors (5-HT2), resulting in vasodilation and decreasing blood pressure. Since the early 1980s, NF has been used to treat several venous and cerebral diseases. There is no data available on the BCS classification of NF. However, based on its physical-chemical properties, NF might be considered to belong to the 1st or the 3rd BCS class. The present study aimed to provide data concerning the solubility and permeability of NF through Caco-2 monolayers and propose its preliminary classification into BCS. We showed that NF is a highly soluble and permeable drug substance; thus, it might be suggested to belong to BCS class I. Additionally, a high dissolution rate of the encapsulated NF based on Praxilene® 100 mg formulation was revealed. Hence, it might be considered as an immediate-release (IR).

scholarly journals Human Keratinocyte Growth and Differentiation on Acellular Porcine Dermal Matrix in relation to Wound Healing Potential

2012 ◽  
Vol 2012 ◽  
pp. 1-8 ◽  
Author(s):  
Robert Zajicek ◽  
Vaclav Mandys ◽  
Ondrej Mestak ◽  
Jan Sevcik ◽  
Radana Königova ◽  
...  
Keyword(s):  
Wound Healing ◽  
Human Keratinocytes ◽  
Dermal Matrix ◽  
Keratinocyte Proliferation ◽  
Proliferation And Differentiation ◽  
A Cell ◽  
Cell Culture Assay ◽  
Air Liquid Interface

A number of implantable biomaterials derived from animal tissues are now used in modern surgery. Xe-Derma is a dry, sterile, acellular porcine dermis. It has a remarkable healing effect on burns and other wounds. Our hypothesis was that the natural biological structure of Xe-Derma plays an important role in keratinocyte proliferation and formation of epidermal architecturein vitroas well asin vivo. The bioactivity of Xe-Derma was studied by a cell culture assay. We analyzed growth and differentiation of human keratinocytes culturedin vitroon Xe-Derma, and we compared the results with formation of neoepidermis in the deep dermal wounds treated with Xe-Derma. Keratinocytes cultured on Xe-Derma submerged in the culture medium achieved confluence in 7–10 days. After lifting the cultures to the air-liquid interface, the keratinocytes were stratified and differentiated within one week, forming an epidermis with basal, spinous, granular, and stratum corneum layers. Immunohistochemical detection of high-molecular weight cytokeratins (HMW CKs), CD29, p63, and involucrin confirmed the similarity of organization and differentiation of the cultured epidermal cells to the normal epidermis. The results suggest that the firm natural structure of Xe-Derma stimulates proliferation and differentiation of human primary keratinocytes and by this way improves wound healing.

scholarly journals High-Frequency, In Vitro Reversible Switching of Candida lusitaniae Clinical Isolates from Amphotericin B Susceptibility to Resistance

1999 ◽  
Vol 43 (4) ◽  
pp. 836-845 ◽  
Author(s):  
Stephanie A. Yoon ◽  
Jose A. Vazquez ◽  
Paul E. Steffan ◽  
Jack D. Sobel ◽  
Robert A. Akins
Keyword(s):  
Amphotericin B ◽  
High Frequency ◽  
Susceptibility Testing ◽  
Uv Light ◽  
In Vitro Study ◽  
Resistant Phenotype ◽  
Serious Infections ◽  
A Cell ◽  
Candida Lusitaniae

ABSTRACT Recent studies have revealed an increase in the incidence of serious infections caused by non-albicans Candidaspecies. Candida lusitaniae is of special interest because of its sporadic resistance to amphotericin B (AmB). The present in vitro study demonstrated that, unlike other Candidaspecies, C. lusitaniae isolates frequently generated AmB-resistant lineages form previously susceptible colonies. Cells switching from a resistant colony to a susceptible phenotype were also detected after treatment with either UV light, heat shock, or exposure to whole blood, all of which increased the frequency of switching. In some C. lusitaniae lineages, after a cell switched to a resistant phenotype, the resistant phenotype was stable; in other lineages, colonies were composed primarily of AmB-susceptible cells. Although resistant and susceptible lineages were identical in many aspects, their cellular morphologies were dramatically different. Switching mechanisms that involve exposure to antifungals may have an impact on antifungal therapeutic strategies as well as on standardized susceptibility testing of clinical yeast specimens.

scholarly journals A Numerical Representation and Classification of Codons to Investigate Codon Alternation Patterns during Genetic Mutations on Disease Pathogenesis

2020 ◽  
Author(s):  
Antara Sengupta ◽  
Pabitra Pal Choudhury ◽  
Subhadip Chakraborty ◽  
Swarup Roy ◽  
Jayanta Kumar Das ◽  
...  
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Chemical Properties ◽  
Numerical Representation ◽  
Missense Mutations ◽  
Disease Pathogenesis ◽  
Physical Density ◽  
Monogenic Diseases

Motivation: Alteration of amino acid is possible due to mutation in codons that could have a potential impact in a diseased condition. Effective mutation analysis can help to predict the fate of the diseased individual which can be validated later by in-vitro experimentations. It may also help an individual who is asymptomatic but having a particular genetic change for early detection and diagnosis during any terminal diseases. We try to investigate the codon alteration patterns and its impact during mutation for the genes known to be responsible for a particular disease.Results: For our current study, we consider neurodegenerative and monogenic diseases. We use numerical representation based on a determinative degree and classification of codons as well as amino acids into three different classes (Strong, Weak and Transition) for the analysis. Our analysis reveals that the strong class codons are highly mutated followed by weak and transition class. We observe that most of the mutations occur in the first or second positions in the codon rather than the third. While looking into the chemical properties of amino acid, we observe that amino acids belong to the aliphatic group are affected most during missense mutations. Our investigation further emphasises that in most of the cases the change in the determinative degree of codon due to mutation is directly proportional to the physical density property. In addition, our scheme gives a more microscopic and alternative representation of the existing codon table that helps in deciphering interesting codon alteration patterns during mutations in disease pathogenesis.

scholarly journals Cytotoxicity as a Fundamental Response to Xenobiotics

2021 ◽  
Author(s):  
Grethel León-Mejía ◽  
Alvaro Miranda Guevara ◽  
Ornella Fiorillo Moreno ◽  
Carolina Uribe Cruz
Keyword(s):  
Medical Devices ◽  
Normal Cell ◽  
Cellular Damage ◽  
In Vitro Tests ◽  
Target Cells ◽  
Cell Physiology ◽  
A Cell ◽  
Division Cell

Cytotoxicity refers to the ability of a molecule or a compound to cause some type of cellular damage, of which some of the adverse effects that can occur include injuries to some structures or the fundamental processes involved in cell maintenance, such as survival, cell division, cell biochemistry, and the normal cell physiology. The potential for cytotoxicity is one of the first tests that must be performed to determine the effects of drugs, biomolecules, nanomaterials, medical devices, pesticides, heavy metals, and solvents, among others. This potential may be oriented in the mechanism under which it generates cell death, the dose, and the target cells that generate the response. The evaluation of the toxicologic and cytotoxic properties of the chemical substances through in vitro tests has become a competitive alternative to in vivo experimentation as a consequence of ethical considerations. Presently, there are numerous tests conducted to evaluate the cytotoxicity of a certain agent, the selection of which depends on the purpose of the study. In this sense, the present review provides a general overview of the different responses of a cell to xenobiotic agents and the different test that can be useful for evaluation of these responses.

Effect of UV Wavelength on Apatite Formation of Anodised Titanium

2015 ◽  
Vol 1125 ◽  
pp. 465-469
Author(s):  
Te Chuan Lee ◽  
Hasan Zuhudi Abdullah ◽  
Maizlinda Izwana Idris
Keyword(s):  
Uv Light ◽  
Chemical Properties ◽  
Light Treatment ◽  
Disodium Salt ◽  
Light Illumination ◽  
Apatite Formation ◽  
Oh Groups ◽  
Novel Method ◽  
Titanium Foils

A novel method to accelerate the apatite formation on the anodised titanium is proposed in this article. The processing was composed of two steps which were UV light treatment after anodic oxidation, and UV light illumination during soaking in simulated body fluid (SBF). This study aims to investigate the effect of different UV wavelengths during SBF on the apatite formation of anodised titanium. The titanium foils were anodised in mixture of β-glycerophosphate disodium salt pentahydrate (β-GP) and calcium acetate monohydrate (CA). Subsequently, the anodised titanium foils were pre-treated with UV light. In vitro was conducted by illuminating with different wavelengths of UV light (254nm and 365nm) in SBF. Field emission scanning electron microscopy (FESEM) and X-ray diffractometer (XRD) were used to characterise the surface morphology and crystallinity of anodised titanium. The results showed that donut-shaped pores with anatase/rutile phases were formed on the surface of anodised titanium. Apart from that, the UV light treatment did change the chemical properties of anodised titanium by producing more •OH groups. After UV light illumination in SBF for 1 week, the anodised titanium foils were fully covered by bone-like apatite.

scholarly journals In Vitro and In Vivo Cell Uptake of a Cell-Penetrating Peptide Conjugated with Fluorescent Dyes Having Different Chemical Properties

Cancers ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 2245
Author(s):  
Hideo Takakura ◽  
Honoka Sato ◽  
Kohei Nakajima ◽  
Motofumi Suzuki ◽  
Mikako Ogawa
Keyword(s):  
Fluorescent Dyes ◽  
Chemical Properties ◽  
Cyanine Dyes ◽  
Cell Uptake ◽  
Cell Penetrating Peptide ◽  
Cell Penetrating ◽  
A Cell ◽  
Targeting Strategy

In molecular imaging, a targeting strategy with ligands is widely used because specificity can be significantly improved. In fluorescence imaging based on a targeting strategy, the fluorescent dyes conjugated with ligands may affect the targeting efficiency depending on the chemical properties. Herein, we used a cell-penetrating peptide (CPP) as a ligand with a variety of fluorescent cyanine dye. We investigated in vitro and in vivo cell uptake of the dye-CPP conjugates when cyanine dyes with differing charge and hydrophilicity/lipophilicity were used. The results showed that the conjugates with positively charged and lipophilic cyanine dyes accumulated in cancer cells in vitro, but there was almost no accumulation in tumors in vivo. On the other hand, the conjugates with negatively charged and hydrophilic cyanine dyes did not accumulate in cancer cells in vitro, but fluorescence was observed in tumors in vivo. These results show that there are some cases in which the cell uptake of the dye-peptide conjugates may differ significantly between in vitro and in vivo experiments due to the chemical properties of the fluorescent dyes. This suggests that attention should be paid to the chemical properties of fluorescent dyes in fluorescence imaging based on a targeting strategy.

Presence of methenamine/glutathione mixtures reduces the cytotoxic effect of sulphur mustard on cultured SVK-14 human keratinocytes in vitro

1997 ◽  
Vol 16 (5) ◽  
pp. 247-253 ◽  
Author(s):  
CN Smith ◽  
CD Lindsay ◽  
DG Upshall
Keyword(s):  
Crystal Violet ◽  
Cultured Cells ◽  
Fold Increase ◽  
Human Keratinocytes ◽  
Neutral Red ◽  
Cell Number ◽  
Cellular Damage ◽  
Epidermal Keratinocytes ◽  
Sulphur Mustard

1 The basal epidermal keratinocytes of the skin are a main target for the vesicating agent, sulphur mustard (SM). A human keratinocyte cell line (SVK-14) has been used to model the effects of SM on the basal epidermal keratinocytes and subsequently to test the efficacy of potential prophylactic compounds in reducing the SM-induced cytotoxicity. 2 The cultures were pretreated with mixtures of methe namine (HMT) and glutathione (GSH) for 1 h prior to exposure to 10 μM SM. The viability of the cultures was then assessed using neutral red (NR) dye uptake and crystal violet DNA staining assays at 24 h intervals post exposure. 3 Pretreatment led to a 1.9 fold increase in culture viability (NR assay) compared to those exposed to SM only, and a 2.3 fold increase in cell number (crystal violet assay). Photomicrography showed that pre treatment preserved the morphology of the cultured cells and maintained their mitotic activity whereas those exposed to SM only show non-proliterative cultures with extensive cellular damage. 4 The results of this study show that it is possible to protect mitotically active cultures from the effects of SM, however the measures must be in place prior to SM exposure.

Ultrastructure of melanocyte-keratinocyte interactions and pigment transfer in vitro

1978 ◽  
Vol 36 (2) ◽  
pp. 650-651
Author(s):  
Raul I. Garcia ◽  
Evelyn A. Flynn ◽  
George Szabo
Keyword(s):  
Direct Injection ◽  
Skin Pigmentation ◽  
Freeze Fracture ◽  
Pigment Granule ◽  
Time Lapse ◽  
Ultrastructural Level ◽  
Lanthanum Tracer ◽  
A Cell

Skin pigmentation in mammals involves the interaction of epidermal melanocytes and keratinocytes in the structural and functional unit known as the Epidermal Melanin Unit. Melanocytes(M) synthesize melanin within specialized membrane-bound organelles, the melanosome or pigment granule. These are subsequently transferred by way of M dendrites to keratinocytes(K) by a mechanism still to be clearly defined. Three different, though not necessarily mutually exclusive, mechanisms of melanosome transfer have been proposed: cytophagocytosis by K of M dendrite tips containing melanosomes, direct injection of melanosomes into the K cytoplasm through a cell-to-cell pore or communicating channel formed by localized fusion of M and K cell membranes, release of melanosomes into the extracellular space(ECS) by exocytosis followed by K uptake using conventional phagocytosis. Variability in methods of transfer has been noted both in vivo and in vitro and there is evidence in support of each transfer mechanism. We Have previously studied M-K interactions in vitro using time-lapse cinemicrography and in vivo at the ultrastructural level using lanthanum tracer and freeze-fracture.

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