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Intrauterine adhesion (IUA) is one of the main causes of female infertility. Extracellular vesicles (EVs) secreted by mesenchymal stem cells (MSCs), are consisted of a complete lipid bilayer structure, rich in multiple factors and miRNAs related to tissue regeneration, which are the main effective paracrine components of MSCs to treat IUA. However, the poor secretion and bioactivity of EVs leading to the unexpected therapeutic efficacy of MSC-EVs, have been obstacles to their widespread use in clinical practice. Here, we developed human chorionic villi (CV)-derived nanofibers that mimic the tissue-specific ECM microenvironment of CV-derived MSCs, maintain the stemness of MSCs for a long time, and are rich in apolipoproteins, HSP90, ANXA1-A6, etc., which can enhance EV secretion and bioactivity. Then, the CV-nanofiber bionic culture system for mesenchymal stem cells was constructed to achieve large-scale cultivation of MSCs for continuous collection of high-concentration EVs enrichment supernatant. Additionally, EVs obtained by this system were encapsulated with CV-nanofibers to form EVs-ECM aggregate, which can effectively promote endometrium regeneration toward supporting fetal development and live births. Our study provides a new idea for enhancing EV secretion and bioactivity, and a cell-free therapy for treating IUA by EVs, thus promoting the potential of clinical application. [Display omitted] • CV-nanofibers contain abundant autologous apolipoproteins, HSP90, ANXA1-A6, etc. • CV-nanofiber bionic culture system optimized the growth microenvironment of CV-MSCs • CV-nanofibers enhanced EV secretion and bioactivity • EVs-ECM aggregate effectively promoted endometrium regeneration toward IUAs [ABSTRACT FROM AUTHOR]

Highlights: [•] A pentasaccharide analog has been synthesized for the first time. [•] The plant growth regulation activity of this analog was studied. [•] The activity data shows the analog can stimulate the growth of wheat coleoptile. [Copyright &y& Elsevier]

Background & Aims: Sirtuin (SIRT1) is a nicotinamide adenine dinucleotide−dependent protein deacetylase that regulates hepatic lipid metabolism by modifying histones and transcription factors. Ethanol exposure disrupts SIRT1 activity and contributes to alcoholic liver disease in rodents, but the exact pathogenic mechanism is not clear. We compared mice with liver-specific deletion of Sirt1 (Sirt1LKO) mice with their LOX littermates (controls). Methods: We induced alcoholic liver injury in male Sirt1LKO and control mice, placing them on Lieber-DeCarli ethanol-containing diets for 10 days and then administering a single dose of ethanol (5 g/kg body weight) via gavage. Liver and serum samples were collected. We also measured messenger RNA levels of SIRT1, SFRS10, and lipin-1β and lipin-1α in liver samples from patients with alcoholic hepatitis and individuals without alcoholic hepatitis (controls). Results: On the ethanol-containing diet, livers of Sirt1LKO mice accumulated larger amounts of hepatic lipid and expressed higher levels of inflammatory cytokines than control mice; serum of Sirt1LKO mice had increased levels of alanine aminotransferase and aspartate aminotransferase. Hepatic deletion of SIRT1 exacerbated ethanol-mediated defects in lipid metabolism, mainly by altering the function of lipin-1, a transcriptional regulator of lipid metabolism. In cultured mouse AML-12 hepatocytes, transgenic expression of SIRT1 prevented fat accumulation in response to ethanol exposure, largely by reversing the aberrations in lipin-1 signaling induced by ethanol. Liver samples from patients with alcoholic hepatitis had reduced levels of SIRT1 and a higher ratio of Lpin1β/α messenger RNAs than controls. Conclusions: In mice, hepatic deletion of Sirt1 promotes steatosis, inflammation, and fibrosis in response to ethanol challenge. Ethanol-mediated impairment of hepatic SIRT1 signaling via lipin-1 contributes to development of alcoholic steatosis and inflammation. Reagents designed to increase SIRT1 regulation of lipin-1 can be developed to treat patients with alcoholic fatty liver disease. [Copyright &y& Elsevier]

Abstract: An efficient synthesis of 4-methoxyphenyl α-l-Rhap-(1→3)-α-l-Rhap-(1→3)-α-l-Rhap-(1→2)-6-deoxy-α-l-Talp, the tetrasaccharide related to the GPLs of Mycobacterium intracellare serotype 7, was achieved with 4-methoxyphenyl 3,4-di-O-benzoyl-6-deoxy-α-l-talopyranoside (6c) as the key intermediate which was obtained through selective 3-O-benzoylation of 4-O-benzoyl-6-deoxy-α-l-taloside. Coupling of 6c with 3-O-allyloxycarbonyl-2,4-di-O-benzoyl-α-l-rhamnopyranosyl trichloroacetimidate followed by removal of the allyloxycarbonyl protecting group afforded the disaccharide acceptor 11. Condensation of 11 with 2,3,4-tri-O-benzoyl-α-l-rhamnopyranosyl-(1→3)-2,4-di-O-benzoyl-α-l-rhamnopyranosyl trichloroacetimidate and subsequent deprotection gave the target tetrasaccharide. [Copyright &y& Elsevier]

Abstract: Rats with streptozotocin-induced diabetes (STZ-D) have reduced serum carnitine levels and bradycardia. Heart rates (HRs) of 24nondiabetic rats (NRs) and 24 STZ-D rats were compared. l-Carnitine (C) was added to the drinking water of rats (12 STZ-D + C) to raise their serum carnitine level. The intrinsic HR for each animal was determined after parasympathetic and sympathetic blockade. The HRs of STZ-D rats (278 ± 15 beats per minute) were less than those of NRs (348 ± 8 beats per minute) (P < .01). STZ-D rats had low serum carnitine compared with control and STZ-D + C rats. The difference in HR of STZ-D rats and NRs continued after blockade, indicating that the bradycardia ofdiabetes is intrinsic to the heart. The metabolic milieu reflected in the rats'' urinary organic acid profiles differed between the control and STZ-D rats. The HR of STZ-D + C rats (326 ± 5 beats per minute) did not differ from those of NRs. Increasing either the insulin dose or the serum free carnitine reduced urinary organic acids, but normal HRs were associated only with elevated serum carnitine levels. When glucose is compromised as a myocardial energy source (diabetes mellitus), we propose that elevated levels of serum carnitine may increase myocardial fatty acid metabolism sufficiently to correct the bradycardia of STZ-D rats. [Copyright &y& Elsevier]

Abstract: A highly regio- and stereoselective anomeric esterification of 3-O-allyl (or benzyl, or benzoyl)-4,6-O-isopropylidene-α,β-d-glucopyranose with acetyl chloride, or allyl chloroformate, or ethyl chloroformate gave the corresponding 2-OH, 1-β-acetates or -carbonates in excellent yields. The 2-OH, 1-β-acetates were readily converted to the corresponding 2-O-acetylated glucopyranosyl trichloroacetimidates by reaction with trichloroacetonitrile via base promoted acetyl migration, while the 2-OH, 1-β-carbonates were good glycosyl acceptors for the synthesis of (1→2)-linked oligosaccharides. [Copyright &y& Elsevier]

PBDEs (polybrominated diphenyl ethers) are environmental pollutants that have been linked to the development of type 2 diabetes, however, the precise mechanisms are not clear. Particularly, their direct effect on insulin secretion is unknown. In this study, we show that two PBDE congeners, BDE-47 and BDE-85, potentiate glucose-stimulated insulin secretion (GSIS) in INS-1 832/13 cells. This effect of BDE-47 and BDE-85 on GSIS was dependent on thyroid receptor (TR). Both BDE-47 and BDE-85 (10 μM) activated Akt during an acute exposure. The activation of Akt by BDE-47 and BDE-85 plays a role in their potentiation of GSIS, as pharmacological inhibition of PI3K, an upstream activator of Akt, significantly lowers GSIS compared to compounds alone. This study shows that BDE-47 and BDE-85 directly act on pancreatic β-cells to stimulate GSIS, and that this effect is mediated by the thyroid receptor (TR) and Akt activation. [ABSTRACT FROM AUTHOR]

Abstract: A highly efficient strategy for the preparation of a disaccharide-repeating unit of the O-antigenic polysaccharide of Burkholderia pseudomallei strain 304b, and its dimer and trimer, has been developed through a regio- and stereoselective manner using p-methoxylphenyl 2,4,6-tri-O-benzoyl-α-d-glucopyranoside and 3-O-allyloxycarbonyl-2,4-di-O-benzoyl-6-deoxy-α-l-talopyranosyl trichloroacetimidate as the key synthons. The target molecules were equipped with a p-methoxylphenyl handle at the reducing terminus to allow for their further functionalization and attachment to a carrier protein. [Copyright &y& Elsevier]

Abstract: The synthesis of a trisaccharide and a hexasaccharide, the monomer and dimer of the repeating unit of O-antigen polysaccharide from Mesorhizobium huakuii IFO15243, has been accomplished through suitable protecting group manipulations and stereoselective glycosylation reactions starting from commercially available l-rhamnose. The target oligosaccharides in the form of their p-methoxyphenyl glycosides are suitable for further glycoconjugate formation via selective cleavage of this group. [ABSTRACT FROM AUTHOR]

Abstract: A series of novel 2-oxocycloalkylsulfonamides (4) were synthesized and their structures confirmed by IR, 1H NMR, and elemental analysis. The bioassay showed that they have fair to excellent fungicidal activities against Botrytis cinerea Pers and Sclerotinia sclerotiorum. Among them, compounds 4A 10, 4A 11, 4A 12, 4B 2, and 4B 3, the EC50 values of which were 2.12, 3.66, 3.96, 2.38, and 2.43μg/mL, respectively, displayed excellent fungicidal activity against B. cinerea Pers, and are comparable with commercial fungicide procymidone (the EC50 value is 2.45μg/mL). 3D QSAR against B. cinerea Pers was studied, a statistically significant and chemically meaningful CoMFA model was developed and some compounds which have a high predicted activity were forecasted. In addition, the bioassay also showed that the compounds have good inhibitory activities against human tumor cells HL-60, BGC-823, Bel-7402 and KB. It is interesting to point out that the antitumor activities of compounds 4 are in accordance with their fungicidal activity to a great extent: compounds having relatively best antitumor activities (4A 10, 4A 11, 4A 12, and 4B 3) also displayed excellent fungicidal activity. [Copyright &y& Elsevier]

Abstract: 1-O-Allyloxycarbonyl (or ethyloxycarbonyl)-2-azido-2-deoxy-3-O-benzyl (or allyl, or benzoyl)-4,6-O-isopropylidene-β-d-mannopyranose derivatives were prepared from the corresponding 2-hydroxy-β-d-glucopyranosyl carbonates in high yields via triflation of the 2-hydroxyl group and subsequent SN2 displacement with azide ion. An N-acetyl-mannosamine-containing trisaccharide, a fragment of the putative O10 antigen from Acinetobacter baumannii, was efficiently synthesized using these derivatives. [Copyright &y& Elsevier]

Human O-GlcNAcase (GH 84) and human β-N-acetyl-D-hexosaminidase (GH 20) from Homo sapiens are two therapeutic enzyme targets that share the same catalytic mechanism but play different physiological roles in vivo. Selective inhibition toward one of these enzymes is therefore of importance to regulate the corresponding bioprocess. Here ten new NAM-thiazoline derivatives were synthesized and subsequently characterized by NMR and HRMS. A preliminary bioassay showed that most of the synthesized compounds exhibited obvious selective inhibition against human O-GlcNAcase over human β-N-acetyl-D-hexosaminidase. Among the compounds tested, compound 7d (IC50 = 6.4 µM, hOGA; IC50>1 mM, hHex ) and 7f (IC50 = 11.9 µM, hOGA; IC50>1 mM, hHex ) proved to be a highly selective and potent inhibitor. Structure–activity relationship analysis indicated a correlation between the inhibitory activity and the size of the groups linked to the thiazoline ring. [ABSTRACT FROM AUTHOR]

Abstract: Novel macrocyclic molecules comprising sulfonyl and acyl moiety at the position N-12a of 16-membered azalides (6a–n) and azalactams (10a–r) scaffold were synthesized from cyclododecanone 1 as starting material via 5 steps and 4 steps, respectively. The antifungal activity of these compounds against Sclerotinia sclerotiorum, Pyricularia oryzae, Botrytis cinerea, Rhizoctonia solani and Phytophthora capsici were evaluated and found that compounds possessing α-exomethylene (6c, 6d, 6e and 6g) showed antifungal activity comparable to commercial fungicide Chlorothalonil against P. oryzae and compounds possessing p-chlorobenzoyl exhibited enhanced antifungal activity than those with other substituents against S. sclerotiorum, P. oryzae, and B. cinerea. These findings suggested that the α-exomethylene and p-chlorobenzoyl may be two potential pharmacological active groups with antifungal activities. [Copyright &y& Elsevier]

Abstract: Concise synthesis of a 6-deoxy-α-l-talose tetrasaccharide, 6-deoxy-α-l-Talp-(1→3)-6-deoxy-α-l-Talp-(1→2)-6-deoxy-α-l-Talp-(1→3)-6-deoxy-α-l-Talp, the dimer of the disaccharide repeating unit of the OPS from Aggregatibacter actinomycetemcomitans serotype c, has been accomplished through suitable protecting group manipulations and stereoselective glycosylation starting from commercially available l-rhamnose. The target oligosaccharide in the form of its p-methoxyphenyl glycoside is suitable for further glycoconjugate formation via selective cleavage of this group. [Copyright &y& Elsevier]