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Technology for the transformation of waste feathers to quality regenerated filaments has been developed. Regardless of superior properties of natural keratin materials, previously developed regenerated materials from keratin had tensile properties much lower than their natural counterparts due to backbone hydrolysis and inefficient reconstruction of disulfide crosslinkages. In this work, tough keratin filaments have been regenerated from white duck feathers via efficient restoration of disulfide crosslinkages using a dithiol reducing agent. Dithiol substantially reserves free thiol groups in the extraction and formed lengthy intermolecular crosslinkages in regenerated keratin filaments. Due to the high degree of intermolecular reconstruction of disulfide bonds and formation of lengthy crosslinkages via dithiol chain-extension, the keratin filaments exhibited considerable improvements in mechanical properties, especially for ductility and water stability. The tenacity and elongation at break were 160.7 MPa and 14%, respectively. The filaments retained about 80% of the tenacity of natural feathers at either dry or wet conditions and demonstrated stretchability 150% higher than natural feathers. The fiber regeneration technology makes it possible to substitute primary fiber sources by renewable poultry feathers. Successful filament substitution or addition can bring more than 88-billion-dollar revenue. The technology not only contributes to a sustainable fiber and poultry industry but adds substantial values to poultry feathers., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Background and Objectives: Methyl 3,4-dihydroxybenzoate (MDHB) has the potential to prevent neurodegenerative diseases (NDDs). The present work investigated its excretion, metabolism, and cytochrome P450-based drug-drug interactions (DDIs)., Methods: After intragastric administration of MDHB, the parent drug was assayed in the urine and faeces of mice. Metabolites of MDHB in the urine, faeces, brain, plasma and liver were detected by liquid chromatography-hybrid quadrupole time-of-flight mass spectrometry (LC-QTOF/MS). A cocktail approach was used to evaluate the inhibition of cytochrome P450 isoforms by MDHB., Results: The cumulative excretion permille of MDHB in the urine and faeces were found to be 0.67 ± 0.31 and 0.49 ± 0.44‰, respectively. A total of 96 metabolites of MDHB were identified, and all IC 50 (half-maximal inhibitory concentration) values of MDHB towards cytochrome P450 isoforms were > 100 μM., Conclusions: The results suggest that MDHB has a low parent drug cumulative excretion percentage and that MDHB has multiple metabolites and is mainly metabolized through the loss of -CH 2 and -CO 2 , the loss of -CH 2 O, ester bond hydrolysis, the loss of -O and -CO 2 , isomerization, methylation, sulfate conjugation, the loss of -CH 2 O and -O and glycine conjugation, glycine conjugation, the loss of two -O groups and alanine conjugation, the loss of -CH 2 O and -O and glucose conjugation, glucuronidation, glucose conjugation, etc., in vivo. Finally, MDHB has a low probability of cytochrome P450-based DDIs.

Background and Objectives: Methyl 3,4-dihydroxybenzoate (MDHB) has the potential to prevent neurodegenerative diseases (NDDs). The present work aims to reveal the pharmacokinetics and tissue distribution characteristics of MDHB., Methods: The pharmacokinetics and tissue distribution of MDHB were analyzed using LC-MS/MS after a single intragastric administration (50 to 450 mg/kg) in mice, and samples were collected from five animals at specific time points., Results: Pharmacokinetic parameters of MDHB following intragastric administrations were: the time to peak concentration (T max ) ranged from 0.033 to 0.07 h, the peak concentration (C max ) ranged from 12,379.158 to 109798.712 μg/l, the elimination half-life (t 1/2z ) ranged from 0.153 to 1.291 h, the area under the curve (AUC 0-∞ ) ranged from 640.654 to 20,241.081 μg/l × h, the mean residence time (MRT 0-∞ ) ranged from 0.071 to 0.206 h, the apparent volume of distribution (V z /F) ranged from 17.538 to 45.244 l/kg, and the systemic clearance (Cl z /F) ranged from 22.541 to 80.807 l/h/kg. The oral bioavailability of MDHB was 23%. The maximum MDHB content was detected in the stomach, and the minimum content was observed in the testes; the peak content in the brain was 15,666.93 ng/g., Conclusions: The pharmacokinetic characteristics of MDHB include fast absorption, high systemic clearance, a short half-life and an oral bioavailability of 23%. Additionally, MDHB permeates the blood-brain barrier (BBB) and is rapidly distributed to all organs. The identification of the pharmacokinetics of MDHB following its oral administration will contribute to further preclinical and clinical studies of its effects.

Congenital hemidysplasia with ichthyosiform nevus and limb defects (CHILD) syndrome is an X-linked autosomal dominant disorder characterized by unilateral congenital hemidysplasia with ichthyosiform erythroderma and ipsilateral limb defects caused by a mutation in the gene encoding NAD[P]H steroid dehydrogenase-like protein (NSDHL) at Xq28. The histopathologic hallmark of skin lesions in CHILD syndrome is psoriasiform epidermis with hyperkeratosis and parakeratosis, and its most striking feature affecting the upper dermis is filling of the papillary dermis with foam cells. Here we present the case of a 9-year-old Chinese girl born with the typical clinical features of CHILD syndrome. Histologic and immunohistochemical evaluation of the skin lesions confirmed the diagnosis and led to identification of a heterozygous point mutation in exon 8 of the NSDHL gene. In addition, we provide a literature review of 26 unrelated CHILD syndrome patients from different countries, caused by 20 unique gene mutations occurring throughout the entire NSDHL gene, to promote understanding and provide a more comprehensive description of this unusual disorder., (© 2015 Wiley Periodicals, Inc.)

A series of 6 novel 2-amino-4, 5-diarylpyrimidines were synthesized by the reaction of isoflavones with guanidine. They were identified by the spectra of IR, 1H NMR, 13C NMR and elemental analysis. The protective effects of 2-amino-4, 5-diarylpyrimidines against oxygen-glucose deprivation leading by sodium hydrosulfite in PC12 cells were studied by MTT method. It was shown that 2-amino-4, 5-diarylpyrimidines exhibited neuroprotective effects against oxygen-glucose deprivation injury in PC12 cells, which could increase the amount of survival PC12 cells and reduce their injured degree in the model.

In determining the replenishment policy for an inventory system, some researchers advocated that the iterative method of Newton could be applied to the derivative of the total cost function in order to get the optimal solution. But this approach requires calculation of the second derivative of the function. Avoiding this complex computation we use another iterative method presented by the second author. One of the goals of this paper is to present a unified convergence theory of this method. Then we give a numerical example to show the application of our theory.