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Contribution of LDI and MALDI for the Characterization of a Lignocellulosic-Based Pyrolysis Bio-Oil.Journal of the American Society For... Aug 2023In recent years, various alternatives to fossil fuels have been developed. One of them involves the production of bio-oils from lignocellulosic-based biomass through...
In recent years, various alternatives to fossil fuels have been developed. One of them involves the production of bio-oils from lignocellulosic-based biomass through pyrolysis. However, bio-oils present numerous heteroatoms and, in particular, oxygen atoms that need to be removed by an upgrading process. To optimize these processes, it is necessary to have good knowledge of the composition of the bio-oils at the molecular level. This work aims to establish the usefulness of laser desorption ionization (LDI) and matrix-assisted laser desorption/ionization (MALDI) techniques on lignocellulosic biomass-based bio-oils. Using a Fourier transform ion cyclotron mass spectrometer (FTICR MS), we showed that MALDI gives more information than LDI. The selectivity of a series of MALDI matrices was investigated, showing that some matrices are selective toward compound families and others ionize a wider range of compounds. In this study, nine proton-transfer matrices and three electron-transfer matrices were used and compared to results obtained in LDI. Dithranol, acetosyringone, and graphene oxide were the three promising matrices selected from all matrices, giving an overall characterization of oxygenated classes in a bio-oil. They allowed the ionization of many more species covering a wide range of polarity, aromaticity, and mass with a homogeneous relative intensity for all molecular classes such as lignin-derivative species, sugars, and lipid-derivative species.
Topics: Humans; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; Pyrolysis; Plant Oils; Lasers
PubMed: 37477530
DOI: 10.1021/jasms.3c00197 -
Der Hautarzt; Zeitschrift Fur... Jun 2021We present a case of a 46-year-old woman suffering from active inflammatory alopecia areata universalis. After frustrating use of topical and systemic glucocorticoids,...
We present a case of a 46-year-old woman suffering from active inflammatory alopecia areata universalis. After frustrating use of topical and systemic glucocorticoids, cream PUVA (psoralen and ultraviolet A) therapy and dithranol in increasing dosage, the patient was treated with 2 × 5 mg per day tofacitinib per os. After about 4-6 months, hair growth commenced, which led to full regrowth of scalp hair over the 18 months of therapy, which was well tolerated. The case shows impressively that the off-label application of tofacitinib is a therapeutic option for alopecia areata.
Topics: Alopecia; Alopecia Areata; Female; Humans; Middle Aged; Piperidines; Pyrimidines; Pyrroles
PubMed: 33044559
DOI: 10.1007/s00105-020-04704-1 -
Journal of the European Academy of... Oct 2015Porokeratotic adnexal ostial nevus (PAON) is a term that encompass porokeratotic eccrine ostial and dermal duct naevus and porokeratotic eccrine and hair follicle... (Review)
Review
BACKGROUND
Porokeratotic adnexal ostial nevus (PAON) is a term that encompass porokeratotic eccrine ostial and dermal duct naevus and porokeratotic eccrine and hair follicle naevus. PAON is a rare adnexal hamartoma characterized by the presence of a cornoid lamella exclusively overlying eccrine acrosyringia or over both, eccrine acrosyringia and hair follicles.
OBJECTIVES
Most of the articles on PAON report its clinical or histopathological characteristics but literature review offer scarce data on the evolution or treatment. We have reviewed it.
CASE REPORT
We report an 8-year-old boy with presence of bilateral asymtomatic verrucous lesions mostly in left side of the body without other added abnormalities through the twelve-year follow-up. As our case presented cornoid lamella overlying eccrine acrosyringia and hair follicles we diagnosed PEHFN. He received treatment with CO2 ablation in 2004 and in 2012 with marked improvement.
RESULTS
Review of the previous reported cases of PAON show that it is mostly unilateral and that some patients have coexisting problems like seizures, left hemiparesis, scoliosis, deafness, developmental delay, palmoplantar keratoderma, psoriasis, hyperthyroidism, polinerupathy, breast hipoplasia and KID.
CONCLUSION
PAON responded with tazaroten gel, dithranol short-contact treatment and topical photodynamic therapy but laser treatments appear to be more efficient in most patients.
Topics: Axilla; Child; Eccrine Glands; Groin; Hair Follicle; Humans; Lasers, Gas; Male; Nevus, Intradermal; Porokeratosis; Sweat Gland Neoplasms
PubMed: 25255914
DOI: 10.1111/jdv.12732 -
International Journal of Molecular... Mar 2023Skin is a major administration route for drugs, and all transdermal formulations must be tested for their capability to overcome the cutaneous barrier. Therefore,...
Skin is a major administration route for drugs, and all transdermal formulations must be tested for their capability to overcome the cutaneous barrier. Therefore, developing highly reliable skin models is crucial for preclinical studies. The current in vitro models are unable to replicate the living skin in all its complexity; thus, to date, excised human skin is considered the gold standard for in vitro permeation studies. However, skin explants have a limited life span. In an attempt to overcome this problem, we used an innovative bioreactor that allowed us to achieve good structural and functional preservation in vitro of explanted human skin for up to 72 h. This device was then used to set up an in vitro inflammatory model by applying two distinct agents mimicking either exogenous or endogenous stimuli: i.e., dithranol, inducing the contact dermatitis phenotype, and the substance P, mimicking neurogenic inflammation. Our in vitro system proved to reproduce inflammatory events observed in vivo, such as vasodilation, increased number of macrophages and mast cells, and increased cytokine secretion. This bioreactor-based system may therefore be suitably and reliably used to simulate in vitro human skin inflammation and may be foreseen as a promising tool to test the efficacy of drugs and cosmetics.
Topics: Humans; Hydrodynamics; Skin; Administration, Cutaneous; Skin Absorption; Inflammation; Pharmaceutical Preparations
PubMed: 37047256
DOI: 10.3390/ijms24076284 -
International Journal of Dermatology Jan 2023
Topics: Humans; Anthralin; Skin; Psoriasis; Staining and Labeling; Face
PubMed: 36073242
DOI: 10.1111/ijd.16405 -
Analytical Chemistry Jul 2017The interplay between the wavelength of the laser and the absorption profile of the matrix constitutes a crucial factor in matrix-assisted laser desorption ionization...
The interplay between the wavelength of the laser and the absorption profile of the matrix constitutes a crucial factor in matrix-assisted laser desorption ionization mass spectrometry (MALDI-MS). Numerous studies have shown that typically best analytical results are obtained if the laser wavelength matches the UV absorption band of the matrix in the solid state well. However, many powerful matrices exhibit peak absorptions which differ notably from the standard MALDI laser wavelengths of 337, 349, and 355 nm, respectively. Here we used two wavelength-tunable lasers to investigate the MALDI wavelength dependence with a selected set of such matrices. We studied 3-hydroxypicolinic acid (3-HPA), 2,4,6-trihydroxyacetophenon (THAP), dithranol (1,8-dihydroxy-10H-anthracen-9-on), 2-(4'-hydroxybenzeneazo)benzoic acid (HABA), and 6-aza-2-thiothymine (ATT). For analyte systems we investigated DNA oligomers (3-HPA), phospholipids (dithranol, THAP, HABA), and non-covalent peptide-peptide and protein-peptide complexes (ATT). We recorded analyte ion and total ion counts as a function of wavelength and laser fluence between 213 and 600 nm. Although the so-generated comprehensive heat maps generally corroborated the previously made findings, several fine features became notable. For example, despite a still high optical absorption exhibited by some of the matrices in the visible wavelength range, ion yields generally dropped strongly, indicating a change in ionization mechanism. Moreover, the non-covalent complexes were optimally detected at wavelengths corresponding to a relatively low optical absorptivity of the ATT matrix, presumably because of ejection of a particular cold MALDI plume. Our comprehensive data shed useful light into the MALDI mechanisms and could assist in further methodological advancement of the technique.
PubMed: 28636332
DOI: 10.1021/acs.analchem.7b01744 -
Pediatric Dermatology Nov 2018Data on treatment options in pediatric alopecia areata are limited. Topical anthralin has been demonstrated to be an effective treatment option in adults and has minimal...
BACKGROUND/OBJECTIVES
Data on treatment options in pediatric alopecia areata are limited. Topical anthralin has been demonstrated to be an effective treatment option in adults and has minimal systemic toxicity. Prior results on its efficacy in children with alopecia areata have been mixed.
METHODS
Medical records of 37 patients with alopecia areata who were started on topical anthralin before age 17 were reviewed for efficacy and safety data. Scalp regrowth was quantified by serial photography if available or by medical record documentation if photographs were unavailable. Mean duration of clinical follow-up was 2.5 years.
RESULTS
Most patients were started on anthralin while continued on prior therapies, including topical corticosteroids, minoxidil, and/or intralesional corticosteroids. Twelve patients (32%) experienced complete scalp regrowth, while 25 patients (68%) experienced at least 50% maximal scalp regrowth with using anthralin. Of the patients with at least 50% scalp regrowth, mean time to first clinically observed response was 3.4 months. Mean time to maximal response was 15 months. Four patients stopped anthralin due to skin irritation. Relapses affected 64% of those with at least 50% maximal scalp regrowth.
CONCLUSIONS
Topical anthralin provides children with alopecia areata an additional option that offers potential for significant scalp regrowth with minimal systemic effects. Treatment course may need to be continued for at least 1 year in order to achieve maximal efficacy. The efficacy of anthralin may be limited by high rate of recurrence and local adverse effects.
Topics: Administration, Topical; Adolescent; Alopecia Areata; Anthralin; Child; Child, Preschool; Dermatologic Agents; Female; Glucocorticoids; Hair; Humans; Male; Minoxidil; Retrospective Studies; Treatment Outcome; Vasodilator Agents
PubMed: 30338548
DOI: 10.1111/pde.13703 -
Frontiers in Microbiology 2020Influenza virus RNA-dependent RNA polymerase (vRdRp) does not have capping activity and relies on the capped RNAs produced by the host RNA polymerase II (RNAPII). The...
Influenza virus RNA-dependent RNA polymerase (vRdRp) does not have capping activity and relies on the capped RNAs produced by the host RNA polymerase II (RNAPII). The viral polymerases process the capped RNAs to produce short capped RNA fragments that are used as primers to initiate the transcription of viral mRNAs. This process, known as cap-snatching, can be targeted by antiviral therapeutics. Here, anthralin was identified as an inhibitor against influenza a virus (IAV) infection by targeting the cap-snatching activity of the viral polymerase. Anthralin, an FDA-approved drug used in the treatment of psoriasis, shows antiviral activity against IAV infection and . Importantly, anthralin significantly reduces weight loss, lung injury, and mortality caused by IAV infection in mice. The mechanism of action study revealed that anthralin inhibits the cap-binding function of PB2 subunit and endonuclease activity of PA. As a result, viral mRNA transcription is blocked, leading to the decreases in viral RNA replication and viral protein expression. In conclusion, anthralin has been demonstrated to have the potential of an alternative antiviral against influenza virus infection. Also, targeting the captive pocket structure that includes the N-terminus of PA endonuclease domain and the C-terminal of PB2 cap-binding domain of IAV RdRp may be an excellent strategy for developing anti-influenza drugs.
PubMed: 32132985
DOI: 10.3389/fmicb.2020.00178 -
The Journal of Biological Chemistry Aug 2016Members of the antibiotic biosynthesis monooxygenase family catalyze O2-dependent oxidations and oxygenations in the absence of any metallo- or organic cofactor. How...
Members of the antibiotic biosynthesis monooxygenase family catalyze O2-dependent oxidations and oxygenations in the absence of any metallo- or organic cofactor. How these enzymes surmount the kinetic barrier to reactions between singlet substrates and triplet O2 is unclear, but the reactions have been proposed to occur via a flavin-like mechanism, where the substrate acts in lieu of a flavin cofactor. To test this model, we monitored the uncatalyzed and enzymatic reactions of dithranol, a substrate for the nogalamycin monooxygenase (NMO) from Streptomyces nogalater As with flavin, dithranol oxidation was faster at a higher pH, although the reaction did not appear to be base-catalyzed. Rather, conserved asparagines contributed to suppression of the substrate pKa The same residues were critical for enzymatic catalysis that, consistent with the flavoenzyme model, occurred via an O2-dependent slow step. Evidence for a superoxide/substrate radical pair intermediate came from detection of enzyme-bound superoxide during turnover. Small molecule and enzymatic superoxide traps suppressed formation of the oxygenation product under uncatalyzed conditions, whereas only the small molecule trap had an effect in the presence of NMO. This suggested that NMO both accelerated the formation and directed the recombination of a superoxide/dithranyl radical pair. These catalytic strategies are in some ways flavin-like and stand in contrast to the mechanisms of urate oxidase and (1H)-3-hydroxy-4-oxoquinaldine 2,4-dioxygenase, both cofactor-independent enzymes that surmount the barriers to direct substrate/O2 reactivity via markedly different means.
Topics: Bacterial Proteins; Catalysis; Dinitrocresols; Mixed Function Oxygenases; Streptomyces; Superoxides
PubMed: 27307041
DOI: 10.1074/jbc.M116.730051 -
Advances in Medical Sciences Mar 2015Psoriasis is a chronic, recurrent, inflammatory disease. Recent investigations indicate its autoimmune pathogenesis. Apoptosis plays an important role in the development...
PURPOSE
Psoriasis is a chronic, recurrent, inflammatory disease. Recent investigations indicate its autoimmune pathogenesis. Apoptosis plays an important role in the development of many autoimmune diseases. The aim of this study was to evaluate the influence of topical treatment of psoriasis on soluble Fas (sFas) and soluble Fas-ligand (sFasL).
MATERIAL/METHODS
Serum concentrations of sFas and sFasL were measured using ELISA in 40 psoriatic patients before and after topical treatment with dithranol and compared to the values obtained from 16 healthy subjects. Data were analyzed with respect to severity of psoriasis, duration of the disease and coexisting obesity, diabetes and hypertension.
RESULTS
We found that serum levels of sFas before (11.9±2.4ng/mL) and after treatment (12.2±2.5ng/mL) were significantly higher in patients with psoriasis as compared to the control group (6.4±1.8ng/mL). Concentrations of sFasL did not differ significantly from healthy subjects, but increased after treatment. The sFas/sFasL ratio was significantly higher in psoriasis (128±47) than in the control group and, even though it tended to decrease after treatment, it still remained higher than in the control group (65±22). Additionally we observed a positive correlation of sFas/sFasL ratio with the age of patients and duration of the disease. Psoriatic patients suffering from hypertension and overweight had significantly higher sFas/sFasL ratio than other psoriatic patients.
CONCLUSIONS
Our data indicate upregulation of the sFas/sFasL system in psoriatic patients. We demonstrate association of sFas/sFasL with commorbidities - components of metabolic syndrome.
Topics: Adult; Fas Ligand Protein; Female; Humans; Male; Middle Aged; Psoriasis; Up-Regulation; fas Receptor
PubMed: 25437350
DOI: 10.1016/j.advms.2014.10.005