On the Reactivity of (S)-Indoline-2-Carboxylic Acid.

(S)-Indoline-2-carboxylic acid (H-(2S)-Ind-OH) possesses the ability to influence the conformation of peptide bonds towards the cis amide isomer in polar solvents. However, its potential utilization as a conformational switch within long peptide sequences poses challenges due to its low reactivity and strong inclination to form diketopiperazines. The present study explores its reactivity under various conditions and proposes synthetic strategies to overcome these limitations.

A LC-QTOF Method for the Determination of PEGDE Residues in Dermal Fillers.

Hyaluronic acid is one of the most important ingredients in dermal fillers, where it is often cross-linked to gain more favorable rheological properties and to improve the implant duration. Poly(ethylene glycol) diglycidyl ether (PEGDE) has been recently introduced as a crosslinker because of its very similar chemical reactivity with the most-used crosslinker BDDE, while giving special rheological properties. Monitoring the amount of the crosslinker residues in the final device is always necessary, but in the case of PEGDE, no methods are available in literature.

Efficacy and safety of a new peeling formulated with a pool of PHAs for the treatment of all skin types, even sensitive.

Background: Actually, the use of chemical peels in cosmetics and dermatology continues to grow due to their versatility, clinical endpoint-directed predictability, and favorable risk profile in comparison to lasers. The chemical peel is a generally safe method for treatment of some skin disorders and to refresh and rejuvenate the skin. The major challenge of chemical peels is the tolerability, that is because of sensitive skin which is one of the most common skin disorders.

Rheological Investigation as Tool to Assess Physicochemical Stability of a Hyaluronic Acid Dermal Filler Cross-Linked with Polyethylene Glycol Diglycidyl Ether and Containing Calcium Hydroxyapatite, Glycine and L-Proline.

(1) Background: Dermal fillers are commonly used in aesthetic practice and their rheological characterization is of much interest today, as well as the stability study of the finished formula against external stimuli of a different nature (biological and physicochemical). Rheological tools have been exploited to characterize the physiochemical behaviour of a hyaluronic acid (HA) based dermal filler subjected to different thermal conditions over time. The collected results provide an index of its rheological stability.

Biophysical and Biological Tools to Better Characterize the Stability, Safety and Efficacy of a Cosmeceutical for Acne-Prone Skin.

(1) Background: Acne is a widespread skin disease, especially among adolescents. Following the COVID-19 pandemic and the use of masks, the problem has been affecting a greater number of people, and the attention of the skin care beauty routine cosmetics has been focused on the "Maskne", caused by the sebum excretion rate (SER) that stimulates microbial proliferation. (2) Methods: the present study was focused on the rheological characterization and quality assurance of the preservative system of an anti-acne serum.

In Vitro Hair Growth Promoting Effect of a Noncrosslinked Hyaluronic Acid in Human Dermal Papilla Cells.

Dermal papilla cells (DPCs) are a source of nutrients and growth factors, which support the proliferation and growth of keratinocytes as well as promoting the induction of new hair follicles and maintenance of hair growth. The protection from reactive oxygen species (ROS) and the promotion of angiogenesis are considered two of the basal mechanisms to preserve the growth of the hair follicle. In this study, a noncrosslinked hyaluronic acid (HA) filler (HYDRO DELUXE BIO, Matex Lab S.

Comparative Physicochemical Analysis among 1,4-Butanediol Diglycidyl Ether Cross-Linked Hyaluronic Acid Dermal Fillers.

(1) Background: Injectable hyaluronic acid (HA) dermal fillers are used in several chirurgical practices and in aesthetic medicine. HA filler stability can be enhanced through different cross-linking technologies; one of the most frequently cross-linker used is 1,4-butanediol diglycidyl ether (BDDE), also present in the HA-BDDE dermal filler family of the company Matex Lab S.p.

Physico-Chemical Characterization and In Vitro Biological Evaluation of a Bionic Hydrogel Based on Hyaluronic Acid and l-Lysine for Medical Applications.

Hyaluronic acid (HA) is an endogenous polysaccharide, whose hydrogels have been used in medical applications for decades. Here, we present a technology platform for stabilizing HA with a biocrosslinker, the amino acid L-lysine, to manufacture bionic hydrogels for regenerative medicine. We synthetized bionic hydrogels with tailored composition with respect to HA concentration and degree of stabilization depending on the envisaged medical use.

The Anti-Ageing and Whitening Potential of a Cosmetic Serum Containing 3--ethyl-l-ascorbic Acid.

Skin ageing has many manifestations such as wrinkles, dryness, hyperpigmentation, and uneven skin tone. Extrinsic and intrinsic factors, especially solar ultraviolet light (UVB), contribute to skin ageing; its main features are brown spots, alterations in melanin pigmentation, and a decrease in collagen and hyaluronic acid linked to oxidative stress. Several studies showed that topical products containing ingredients with antioxidant activity can reduce oxidative damage; to provide a maximum anti-ageing effect to the skin, topical products can combine various ingredients.

Toward Physicochemical and Rheological Characterization of Different Injectable Hyaluronic Acid Dermal Fillers Cross-Linked with Polyethylene Glycol Diglycidyl Ether.

(1) Background: Injectable hyaluronic acid (HA) dermal fillers are used to restore volume, hydration and skin tone in aesthetic medicine. HA fillers differ from each other due to their cross-linking technologies, with the aim to increase mechanical and biological activities. One of the most recent and promising cross-linkers is polyethylene glycol diglycidyl ether (PEGDE), used by the company Matex Lab S.

Thumberg: Phytochemistry, Pharmacology, Toxicology and Regulatory Framework for Its Use in the European Union.

Thunberg is an herbal plant, belonging to the Rhamnaceae family, widespread in west Asia, USA, Australia and New Zealand, but still almost unknown in Western countries. H. has been described to possess several pharmacological properties, such as antidiabetic, anticancer, antioxidant, anti-inflammatory and hepatoprotective, especially in the hangover treatment, validating its use as an herbal remedy in the Chinese Traditional Medicine.

In Vitro Evaluation of the Effect of a Not Cross-Linked Hyaluronic Acid Hydrogel on Human Keratinocytes for Mesotherapy.

The multicomponent preparations for mesotherapy are based on the principle that skin and hair aging can be prevented by supplying the fundamental substrates for correct cellular functioning, such as nucleotides, vitamins, amino acids, and biomolecules including hyaluronic acid (HA) that promote skin hydration and several biological activities. The study provides evidence for the application of HYDRO DELUXE BIO (Matex Lab S.p.

Evaluation of the Biological Availability of Hyaluronic Acid Polyethylene Glycols-Cross-Linked Hydrogels to Bovine Testes Hyaluronidase.

During last years, hyaluronic acid- (HA-) based dermal fillers have grown rapidly and continuously, as reported by the American Society of Aesthetic Plastic Surgery (ASAPS). In fact, HA fillers are considered the gold standard technique for soft tissue augmentation, deep skin hydration, and facial recontouring, playing a key role as an alternative to plastic surgery. HA fillers are less invasive, more biocompatible, and safer and with a more natural and immediate result if compared to plastic surgery.

Chemical Characterization of Hydrogels Crosslinked with Polyethylene Glycol for Soft Tissue Augmentation.

Background: Hyaluronic acid (HA) based hydrogels for esthetic applications found widespread use. HA should be crosslinked for this application to achieve the correct viscoelastic properties and avoid fast degradation by the hyaluronidase enzyme naturally present in the skin: these properties are controlled by the amount of crosslinker and the fraction that is effectively crosslinked (i.e.

Evaluation of the Sensitivity of a Hyaluronic Acid PEG Cross-Linked to Bovine Testes Hyaluronidase.

Neauvia Intense is biocompatible, injectable hyaluronic acid (HA) filler PEG cross-linked for facial soft-tissue augmentation that provides volume to tissues. The aim of the present study is to evaluate the sensitivity of Neauvia Intense in hyaluronidase from bovine testes in a time-course analysis. The test is based on the colourimetric determination of the N-acetyl - D - glucosamine (NAG) released by the hyaluronidase in standardised conditions.

Evaluation of the Biosafety of Hyaluronic Acid PEG Cross-Linked with Micromolecules of Calcium Hydroxyapatite in Low Concentration.

Objective: Neauvia Stimulate is biocompatible, injectable hyaluronic acid (HA) filler (26 mg/ml) PEG cross-linked with 1% of calcium hydroxyapatite (CaHA) for facial soft-tissue augmentation that provides volume to tissues, followed by process of neocollagenesis for improving skin quality.

Aim: The aim of the present study is to evaluate the biosafety of the product (Lot. 160517-26-1/2 PEG) on human keratinocytes cultured in vitro.

In vitro evaluation of collagen production on human fibroblasts treated with hyaluronic acid peg cross-linked with micromolecules of calcium hydroxyapatite in low concentration.

Neauvia Stimulate® is a biocompatible, injectable hyaluronic acid (HA) filler (26 mg/ml) PEG cross-linked with 1% of calcium hydroxyapatite (CaHA) for facial soft-tissue augmentation that provides volume to tissues, followed by a process of neocollagenesis for improving skin quality. The aim of the present study is to evaluate the possible modulation of collagen synthesis after treating human fibroblasts cultured in vitro with the product (Lot. 160517-26-1/2 PEG).