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Clinical, Cosmetic and Investigational... 2022Seborrheic dermatitis (SD) is a common chronic inflammatory skin disorder that mostly affects young adults in areas rich in sebaceous glands (scalp, face, and trunk). In... (Review)
Review
Seborrheic dermatitis (SD) is a common chronic inflammatory skin disorder that mostly affects young adults in areas rich in sebaceous glands (scalp, face, and trunk). In adolescents and adults, SD clinical presentation may range from mild patches to diffuse scalp scaling. In infants, it mainly occurs on the scalp as yellowish, scaly patches ("cradle cap"). In adults, several environmental triggers are likely to promote SD development, along with fungal colonization by spp., sebaceous gland activity, as well as immunosuppression, endocrine, neurogenic and iatrogenic factors. In children, early occurrence in the first trimester suggests the role of excessive sebaceous gland activity from maternal hormones, along with cutaneous microbiome alterations. The diagnosis of SD is usually clinical, and specific laboratory and/or instrumental investigations are seldom required. Treatment is aimed at modulating sebum production, reducing skin colonization by spp., and controlling inflammation. In adults, mild-to-moderate scalp SD forms can be managed with topical antifungals (ketoconazole, ciclopirox, miconazole) or antiinflammatory (mild-to-moderate potency corticosteroids) or keratolytic/humectant (propylene glycol) agents. Recommended topical therapeutic options for mild-to-moderate facial or body areas SD include topical ketoconazole, ciclopirox, clotrimazole, mild-to-moderate potency corticosteroids, lithium succinate/gluconate, and topical calcineurin inihibitors (). In severe and/or resistant cases, the use of systemic antifungal drugs (terbinafine, itraconazole), as well as UVB phototherapy, may be considered. In children, scant scientific evidence supports the effectiveness and safety of topical drugs, and "cradle cap" is usually successfully managed with baby shampoos enriched with emollient agents and vegetable oils. Alternatively, similarly to adult scalp SD, medical device shampoos with antiinflammatory and antifungal properties, containing piroctone olamine, bisabolol, alyglicera, telmesteine, may be used. Beyond pharmacological treatments, an appropriate cosmetic approach, if correctly prescribed, may improve therapeutic outcomes.
PubMed: 35967915
DOI: 10.2147/CCID.S284671 -
Cell Transplantation 2021The origins of low-temperature tissue storage research date back to the late 1800s. Over half a century later, osmotic stress was revealed to be a main contributor to... (Review)
Review
The origins of low-temperature tissue storage research date back to the late 1800s. Over half a century later, osmotic stress was revealed to be a main contributor to cell death during cryopreservation. Consequently, the addition of cryoprotective agents (CPAs) such as dimethyl sulfoxide (DMSO), glycerol (GLY), ethylene glycol (EG), or propylene glycol (PG), although toxic to cells at high concentrations, was identified as a necessary step to protect against rampant cell death during cryopreservation. In addition to osmotic stress, cooling and thawing rates were also shown to have significant influence on cell survival during low temperature storage. In general, successful low-temperature cell preservation consists of the addition of a CPA (commonly 10% DMSO), alone or in combination with additional permeating or non-permeating agents, cooling rates of approximately 1ÂșC/min, and storage in either liquid or vapor phase nitrogen. In addition to general considerations, cell-specific recommendations for hepatocytes, pancreatic islets, sperm, oocytes, and stem cells should be observed to maximize yields. For example, rapid cooling is associated with better cryopreservation outcomes for oocytes, pancreatic islets, and embryonic stem cells while slow cooling is recommended for cryopreservation of hepatocytes, hematopoietic stem cells, and mesenchymal stem cells. Yields can be further maximized by implementing additional pre-cryo steps such as: pre-incubation with glucose and anti-oxidants, alginate encapsulation, and selecting cells within an optimal age range and functional ability. Finally, viability and functional assays are critical steps in determining the quality of the cells post-thaw and improving the efficiency of the current cryopreservation methods.
Topics: Cell Survival; Cryopreservation; Cryoprotective Agents; Humans
PubMed: 33757335
DOI: 10.1177/0963689721999617 -
Skin Health and Disease Feb 2023Ichthyosis vulgaris is an inherited, non-syndromic form of ichthyosis that presents with skin problems. Making up more than 95% cases of ichthyosis, ichthyosis vulgaris... (Review)
Review
Ichthyosis vulgaris is an inherited, non-syndromic form of ichthyosis that presents with skin problems. Making up more than 95% cases of ichthyosis, ichthyosis vulgaris is caused by heterozygous loss-of-function mutation of the filaggrin gene, raising the fragility and permeability of the stratum corneum. It typically presents in infancy as xerosis, skin lesions, keratosis pilaris, palmoplantar hyper linearity, scaly dermatosis, and erythroderma, clearly identifiable by age 5. Although majority of patients have a normal lifespan, possible complications include a vitamin D deficiency and auditory problems due to scaling in the ears, besides a drop in quality of life due to dermatological changes. Urea-based creams with 10% urea, ceramides, and other ceramides are often the first line therapy in ichthyosis vulgaris. There is no known curative treatment for ichthyosis vulgaris, but lifelong treatment can alleviate the symptoms. Urea-based creams are highly therapeutic, whereas ammonium lactate 12% lotion with a physiological lipid-based repair cream can help with scaling and dryness. There is also evidence in favour of propylene glycol solutions. Risankizumab, an anti-interleukin-23 drug, and enhancement of natural moisturizing factors are also two highly promising solutions that require additional research. This review aims to provide updates on the manifestation, evaluation, and treatment of ichthyosis vulgaris.
PubMed: 36751330
DOI: 10.1002/ski2.187 -
The Journal of Allergy and Clinical... Aug 2021Excipients are necessary as a support to the active ingredients in drugs, vaccines, and other products, and they contribute to their stability, preservation,... (Review)
Review
Excipients are necessary as a support to the active ingredients in drugs, vaccines, and other products, and they contribute to their stability, preservation, pharmacokinetics, bioavailability, appearance, and acceptability. For both drugs and vaccines, these are rare reactions; however, for vaccines, they are the primary cause of immediate hypersensitivity. Suspicion for these "hidden dangers" should be high, in particular, when anaphylaxis has occurred in association with multiple chemically distinct drugs. Common excipients implicated include gelatin, carboxymethylcellulose, polyethylene glycols, and products related to polyethylene glycols in immediate hypersensitivity reactions and propylene glycol in delayed hypersensitivity reactions. Complete evaluation of a suspected excipient reaction requires detailed information from the product monograph and package insert to identify all ingredients that are present and to understand the function and structure for these chemicals. This knowledge helps develop a management plan that may include allergy testing to identify the implicated component and to give patients detailed information for future avoidance of relevant foods, drugs, and vaccines. Excipient reactions should be particularly considered for specific classes of drugs where they have been commonly found to be the culprit (eg, corticosteroids, injectable hormones, immunotherapies, monoclonal antibodies, and vaccines). We provide a review of the evidence-based literature outlining epidemiology and mechanisms of excipient reactions and provide strategies for heightened recognition and allergy testing.
Topics: Anaphylaxis; Drug Hypersensitivity; Excipients; Humans; Hypersensitivity; Hypersensitivity, Immediate; Polyethylene Glycols; Vaccines
PubMed: 33737254
DOI: 10.1016/j.jaip.2021.03.002 -
EMBO Molecular Medicine Dec 2023Viruses are vulnerable as they transmit between hosts, and we aimed to exploit this critical window. We found that the ubiquitous, safe, inexpensive and biodegradable...
Viruses are vulnerable as they transmit between hosts, and we aimed to exploit this critical window. We found that the ubiquitous, safe, inexpensive and biodegradable small molecule propylene glycol (PG) has robust virucidal activity. Propylene glycol rapidly inactivates a broad range of viruses including influenza A, SARS-CoV-2 and rotavirus and reduces disease burden in mice when administered intranasally at concentrations commonly found in nasal sprays. Most critically, vaporised PG efficiently abolishes influenza A virus and SARS-CoV-2 infectivity within airborne droplets, potently preventing infection at levels well below those tolerated by mammals. We present PG vapour as a first-in-class non-toxic airborne virucide that can prevent transmission of existing and emergent viral pathogens, with clear and immediate implications for public health.
Topics: Animals; Mice; Humans; Respiratory Aerosols and Droplets; Influenza, Human; Influenza A virus; COVID-19; Propylene Glycols; Mammals
PubMed: 37970627
DOI: 10.15252/emmm.202317932 -
Circulation Research Apr 2023The use of electronic nicotine delivery systems, specifically electronic cigarettes (e-cig), has risen dramatically within the last few years; the demographic purchasing... (Review)
Review
The use of electronic nicotine delivery systems, specifically electronic cigarettes (e-cig), has risen dramatically within the last few years; the demographic purchasing these devices is now predominantly adolescents that are not trying to quit the use of traditional combustible cigarettes, but rather are new users. The composition and appearance of these devices has changed since their first entry into the market in the late 2000s, but they remain composed of a battery and aerosol delivery system that is used to deliver breakdown products of propylene glycol/vegetable glycerin, flavorings, and potentially nicotine or other additives. Manufacturers have also adjusted the type of nicotine that is used within the liquid to make the inhalation more palatable for younger users, further affecting the number of youth who use these devices. Although the full spectrum of cardiovascular and cardiometabolic consequences of e-cig use is not fully appreciated, data is beginning to show that e-cigs can cause both short- and long-term issues on cardiac function, vascular integrity and cardiometabolic issues. This review will provide an overview of the cardiovascular, cardiometabolic, and vascular implications of the use of e-cigs, and the potential short- and long-term health effects. A robust understanding of these effects is important in order to inform policy makers on the dangers of e-cigs use.
Topics: Humans; Adolescent; Nicotine; Electronic Nicotine Delivery Systems; Lung; Vaping; Cardiovascular Diseases
PubMed: 37104558
DOI: 10.1161/CIRCRESAHA.123.321565 -
Journal of Colloid and Interface Science Sep 2023Because particle-stabilised foams are extremely stable and have a yield stress, a particle-stabilised aqueous foam and a particle-stabilised oil foam can be mixed...
HYPOTHESIS
Because particle-stabilised foams are extremely stable and have a yield stress, a particle-stabilised aqueous foam and a particle-stabilised oil foam can be mixed together to give a stable composite foam which brings together two immiscible liquids.
EXPERIMENTS
We have developed a mixed foam system comprised of an olive oil foam with bubbles stabilised using partially fluorinated particles and an aqueous foam with bubbles stabilised using hydrophobic silica particles. The aqueous phase is a mixture of water and propylene glycol. We have studied this system using bulk observations, confocal microscopy and rheology as we vary the proportions of the two foams, the silica particles and the propylene glycol, and the sample age.
FINDINGS
The composite foam resembles an emulsion of one foam within another and is stable for a week or more. The structure and flow properties depend on the proportions of the two phases and the quantities of both silica particles and propylene glycol. Inversion between water-in-oil and oil-in-water is observed, where both phases are foams, driven both by silica wettability and by adding increasing quantities of the dispersed foam. Composites formed at the inversion point are the least stable, showing significant phase separation in less than one week.
PubMed: 37224681
DOI: 10.1016/j.jcis.2023.05.068 -
Regulatory Toxicology and Pharmacology... Feb 2023Propylene glycol (PG) has widespread use in pharmaceuticals, cosmetics, fragrances and personal care products. PG is not classified as hazardous under the Globally... (Review)
Review
Propylene glycol (PG) has widespread use in pharmaceuticals, cosmetics, fragrances and personal care products. PG is not classified as hazardous under the Globally Harmonised System of Classification and Labelling of Chemicals (GHS) but poses an intriguing scientific and regulatory conundrum with respect to allergic contact dermatitis (ACD), the uncertainty being whether and to what extent PG has the potential to induce skin sensitisation. In this article we review the results of predictive tests for skin sensitisation with PG, and clinical evidence for ACD. Patch testing in humans points to PG having the potential to be a weak allergen under certain conditions, and an uncommon cause of ACD in subjects without underlying/pre-disposing skin conditions. In clear contrast PG is negative in predictive toxicology tests for skin sensitisation, including guinea pig and mouse models (e.g. local lymph node assay), validated in vitro test methods that measure various key events in the pathway leading to skin sensitisation, and predictive methods in humans (Human Repeat Insult Patch and Human Maximisation Tests). We here explore the possible scientific basis for this intriguing inconsistency, recognising there are arguably no known contact allergens that are universally negative in, in vitro, animal and human predictive tests methods.
Topics: Mice; Humans; Animals; Guinea Pigs; Dermatitis, Allergic Contact; Skin; Allergens; Skin Tests; Patch Tests; Propylene Glycol; Cosmetics
PubMed: 36702195
DOI: 10.1016/j.yrtph.2023.105341 -
Cryobiology Oct 2022Vitrification is a promising cryopreservation technique for complex specimens such as tissues and organs. However, it is challenging to identify mixtures of...
Vitrification is a promising cryopreservation technique for complex specimens such as tissues and organs. However, it is challenging to identify mixtures of cryoprotectants (CPAs) that prevent ice formation without exerting excessive toxicity. In this work, we developed a multi-CPA toxicity model that predicts the toxicity kinetics of mixtures containing five of the most common CPAs used in the field (glycerol, dimethyl sulfoxide (DMSO), propylene glycol, ethylene glycol, and formamide). The model accounts for specific toxicity, non-specific toxicity, and interactions between CPAs. The proposed model shows reasonable agreement with training data for single and binary CPA solutions, as well as ternary CPA solution validation data. Sloppy model analysis was used to examine the model parameters that were most important for predictions, providing clues about mechanisms of toxicity. This analysis revealed that the model terms for non-specific toxicity were particularly important, especially the non-specific toxicity of propylene glycol, as well as model terms for specific toxicity of formamide and interactions between formamide and glycerol. To demonstrate the potential for model-based design of vitrification methods, we paired the multi-CPA toxicity model with a published vitrification/devitrification model to identify vitrifiable CPA mixtures that are predicted to have minimal toxicity. The resulting optimized vitrification solution composition was a mixture of 7.4 molal glycerol, 1.4 molal DMSO, and 2.4 molal formamide. This demonstrates the potential for mathematical optimization of vitrification solution composition and sets the stage for future studies to optimize the complete vitrification process, including CPA mixture composition and CPA addition and removal methods.
Topics: Cryopreservation; Cryoprotective Agents; Dimethyl Sulfoxide; Ethylene Glycol; Formamides; Glycerol; Ice; Propylene Glycol; Vitrification
PubMed: 36113568
DOI: 10.1016/j.cryobiol.2022.09.002