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Lipopolysaccharides from Bacteroides vulgatus represent interesting targets for the treatment of inflammatory bowel diseases. However, efficient access to long, branched and complex lipopolysaccharides remains challenging. Herein, we report the modular synthesis of a tridecasaccharide from Bacteroides vulgates through an orthogonal one‐pot glycosylation strategy based on glycosyl ortho‐(1‐phenylvinyl)benzoates, which avoids the issues of thioglycoside‐based one‐pot synthesis. Our approach also features: 1) 5,7‐O‐di‐tert‐butylsilylene‐directed glycosylation for stereoselective construction of the α‐Kdo linkage; 2) hydrogen‐bond‐mediated aglycone delivery for the stereoselective formation of β‐mannosidic bonds; 3) remote anchimeric assistance for stereoselective assembly of the α‐fucosyl linkage; 4) several orthogonal one‐pot synthetic steps and strategic use of orthogonal protecting groups to streamline oligosaccharide assembly; 5) convergent [1+6+6] one‐pot synthesis of the target. [ABSTRACT FROM AUTHOR]

Lipopolysaccharides from Bacteroides vulgatus represent interesting targets for the treatment of inflammatory bowel diseases. However, efficient access to long, branched and complex lipopolysaccharides remains challenging. Herein, we report the modular synthesis of a tridecasaccharide from Bacteroides vulgates through an orthogonal one‐pot glycosylation strategy based on glycosyl ortho‐(1‐phenylvinyl)benzoates, which avoids the issues of thioglycoside‐based one‐pot synthesis. Our approach also features: 1) 5,7‐O‐di‐tert‐butylsilylene‐directed glycosylation for stereoselective construction of the α‐Kdo linkage; 2) hydrogen‐bond‐mediated aglycone delivery for the stereoselective formation of β‐mannosidic bonds; 3) remote anchimeric assistance for stereoselective assembly of the α‐fucosyl linkage; 4) several orthogonal one‐pot synthetic steps and strategic use of orthogonal protecting groups to streamline oligosaccharide assembly; 5) convergent [1+6+6] one‐pot synthesis of the target. [ABSTRACT FROM AUTHOR]

Nitrogen is an important factor that influences the yield and quality of wheat grain. However, little is known about its effect on the different positions of the grain in spikelets. Compared with the control group, nitrogen application increased the weight, starch content, and protein content of grains in each position considerably. In particular, the protein content in high grain positions of Yangmai 13 (YM 13) under nitrogen treatment are similar to those positions in Yannong 19 (YN 19) under normal levels. Nitrogen application substantially increased the volume proportion of small starch granules and the average degree of polymerization (DP) but reduced the apparent amylose content (AAC), and the breakdown values (BV) of the first grain (G1) and the second grain (G2) in YN19. Nitrogen application considerably increased AAC, the volume proportion of small starch granules, and the ordered structure of starch surface of G1 and AAC, BV, and DP of G2 in YM13. These results demonstrated that a medium nitrogen level is conducive to increase the agronomic traits in high‐position grains and a better pasting properties of starch in low‐position grains. [ABSTRACT FROM AUTHOR]

Berberine suppresses advanced glycation end products-associated diabetic retinopathy in hyperglycemic mice To determine whether the inhibitory effect of BBR on VEGF production was mediated by its inhibition of STAT3, we transfected a plasmid encoding constitutively activated STAT3 mutant (STAT3C) into BBR-treated HRECs. The cytotoxicity of BBR on HREC cells was measured by MTT assay and the inhibitory concentration (IC)20 of BBR was calculated as 25.11 M. Doses of BBR lower than the IC20 were considered non-toxic to HREC cells. The formation of advanced glycation end products (AGEs) and AGEs-related signalling pathway activation in the retina leads to the initiation of retinopathy in diabetic patients.1 In this study, we identified the natural compound berberine (BBR) as a potent AGEs inhibitor that significantly suppressed AGEs formation and its related TLR4/STAT3/VEGF signalling pathway in the retina endothelial cells, thus contributing to its therapeutic effect on diabetic retinopathy (DR). [Extracted from the article]

Ge–As–Se chalcogenide glasses were prepared and the surface damage characteristics under femtosecond laser irradiation were experimentally investigated. Femtosecond laser beams with different power intensities, focusing depths, pulse repetition rates, and pulse numbers were employed to determine the damage thresholds of the samples. The surface morphologies and feature sizes of the damage craters were studied with regard to laser energy density to evaluate the damage circumstances of the glasses. The generation of the surface damage was also recorded by using different numbers of pulses. Results showed that the damage area increased monotonically with the laser power at low energy density and tended to saturation when reaching a critical value. According to the linear circumstances of laser energy density on the damage crater area, the average damage thresholds of the Ge–As–Se glasses with different repetition rates and pulse numbers were obtained. Results showed that the damage threshold decreased with the increase in pulse repetition rate and number of pulse. [ABSTRACT FROM AUTHOR]

New Findings: What is the central question of this study?The aim was to investigate the role of μ‐opioid receptors in acute respiratory distress syndrome and whether their protective effect is mediated via the PI3K/Akt signalling pathway.What is the main finding and its importance?Our findings show that activation of μ‐opioid receptors ameliorates lung injury, and the effects are reversed by the PI3K inhibitor, wortmannin. The main pathology of acute respiratory distress syndrome (ARDS) is the accumulation of inflammatory cells in the lung and increased permeability of vascular endothelial cells. The μ‐opioid receptor (MOR) is a G‐protein‐coupled receptor, which stimulates angiogenesis and vascular endothelial cell proliferation. In addition, the MOR inhibits cell apoptosis via the PI3K/Akt signalling pathway. In this study, we aimed to explore the contribution of the MOR in ARDS and whether its effects are mediated via PI3K/Akt signalling. An ARDS model was established by intratracheal instillation of 5 mg kg−1 lipopolysaccharide (LPS). Lung injury was confirmed by Haematoxylin and Eosin staining, lung wet/dry weight ratio, bronchoalveolar lavage fluid protein concentrations, myeloperoxidase activity and vascular cell adhesion molecule 1 expression. Lung inflammation was determined by assessment of interleukin‐1β and tumour necrosis factor‐α concentrations. The protein level of p‐Akt was detected by western blot. Endomorphin‐1‐activated MORs attenuated LPS‐induced lung injury, lung wet/dry weight ratio, bronchoalveolar lavage fluid protein concentrations, myeloperoxidase activity, interleukin‐1β and tumour necrosis factor‐α levels and vascular cell adhesion molecule 1 expression, and elevated LPS‐induced decreased p‐Akt expression. However, the protective effect of MOR activation on lung injury was reversed by the PI3K inhibitor, wortmannin. In conclusion, MOR involvement in LPS‐induced ARDS is via the PI3K/Akt pathway. [ABSTRACT FROM AUTHOR]

Summary: Preeclampsia (PE) is a leading cause of maternal and perinatal death. Accumulated evidence suggests that many long non‐coding RNAs (lncRNAs) are abnormally expressed in placentas from PE patients, and they may play functional roles in the development of PE. The present study aimed to investigate the functional role TUG1 in PE and explore the potential molecular mechanisms. Clinically, the expression of TUG1 in placental tissues from PE and normal controls was determined. In vitro, human trophoblast HTR‐8/SVneo and JAR cells were employed for loss or gain‐of‐function assays. Our results demonstrate that TUG1 was downregulated in PE placental tissues compared with normal controls. Moreover, downregulation of TUG1 inhibited the migration and invasion of trophoblast‐like cells. Bioinformatics analysis and functional assays showed that TUG1 interacted with miR‐204‐5p and negatively regulated the expression and function of miR‐204‐5p in trophoblast cells. Furthermore, TUG1‐mediated migration and invasion of trophoblast cells was regulated by miR‐204‐5p. Together, our results suggested that TUG1 regulates trophoblast migration and invasion partly through sponging miR‐204‐5p, and the TUG1/miR‐204‐5p axis could be a potential therapeutic target for the treatment of PE. [ABSTRACT FROM AUTHOR]

Inside Cover: Modular Synthesis of a Tridecasaccharide Motif of Bacteroides vulgatus Lipopolysaccharides against Inflammatory Bowel Diseases through an Orthogonal One-Pot Glycosylation Strategy (Angew. Keywords: Anti-Inflammatory Activity; Lipopolysaccharides; Oligosaccharide Synthesis; Orthogonal One-Pot Glycosylation; Stereoselectivity EN Anti-Inflammatory Activity Lipopolysaccharides Oligosaccharide Synthesis Orthogonal One-Pot Glycosylation Stereoselectivity 1 1 1 05/16/23 20230522 NES 230522 B Lipopolysaccharides b from I Bacteroides vulgatus i represent interesting targets for the treatment of inflammatory bowel diseases. Anti-Inflammatory Activity, Lipopolysaccharides, Oligosaccharide Synthesis, Orthogonal One-Pot Glycosylation, Stereoselectivity. [Extracted from the article]

In their Research Article (e202301351), Guozhi Xiao and co-workers accomplished the first synthesis of a tridecasaccharide motif from I Bacteroides vulgatus i lipopolysaccharides by a strategy involving orthogonal one-pot glycosylation reactions based on glycosyl I ortho i -(1-phenylvinyl)benzoates, which avoided issues such as aglycone transfer and the unpleasant odor of thioglycoside-based orthogonal one-pot glycosylation. Anti-Inflammatory Activity, Lipopolysaccharides, Oligosaccharide Synthesis, Orthogonal One-Pot Glycosylation, Stereoselectivity Keywords: Anti-Inflammatory Activity; Lipopolysaccharides; Oligosaccharide Synthesis; Orthogonal One-Pot Glycosylation; Stereoselectivity EN Anti-Inflammatory Activity Lipopolysaccharides Oligosaccharide Synthesis Orthogonal One-Pot Glycosylation Stereoselectivity 1 1 1 05/16/23 20230522 NES 230522 B Lipopolysaccharides b from I Bacteroides vulgatus i represent interesting targets for the treatment of inflammatory bowel diseases. [Extracted from the article]

Insufficient trophoblast invasion often occurs in patients experiencing preeclampsia. The 67-kDa laminin receptor ( LR1) is a multifunctional protein that binds to laminin and interacts with the extracellular matrix. We recently demonstrated that LR1 is implicated in trophoblast migration and invasion. However, whether LR1 is involved in hypoxia-mediated trophoblastic invasion remains unclear and requires further investigation. This study demonstrates that two trophoblast-like cell lines ( JEG3 and BeWo cells) cultured at 3% oxygen exerted enhanced migratory and invasive capabilities as compared with their counterparts exposed to 20% oxygen. LR1 expression was increased in hypoxic JEG3 cells but decreased after transfection with hypoxia-inducible factor 1 alpha ( HIF-1 α) specific si RNA. Moreover, sh RNA targeting LR1 m RNA significantly inhibited hypoxia-induced increase in matrix metalloproteinase ( MMP)-9 activity in JEG3 cells. Forced overexpression of LR1 augmented JEG3 cell migration and invasion, and enhanced MMP-9 expression and activity. Additionally, the blockade of the MMP-9 effect with its neutralizing antibody reduced LR1 elevation-promoted trophoblastic invasion. In summary, this study demonstrates that LR1 contributes to hypoxia-induced migration and invasion of trophoblast cells at least partly by mediating MMP-9 in vitro. [ABSTRACT FROM AUTHOR]

New Findings What is the central question of this study? What are the effects of protein kinase C (PKC) and Ca2+-calmodulin-dependent protein kinase II (CaMKII) on late sodium current ( INaL), reverse Na+-Ca2+ exchange current (reverse INCX) or intracellular Ca2+ levels changed by ouabain?, What is the main finding and its importance? Ouabain, even at low concentrations (0.5-8.0 μ m), can increase INaL and reverse INCX, and these effects may contribute to the effect of the glycoside to increase Ca2+ transients and contractility. Both PKC and CaMKII activities may mediate or modulate these processes., It has been reported that the cardiac glycoside ouabain can increase the late sodium current ( INaL), as well as the diastolic intracellular calcium concentration and contractile shortening. Whether an increase of INaL participates in a pathway that can mediate the positive inotropic response to ouabain is unknown. We therefore determined the effects of ouabain on INaL, reverse Na+-Ca2+ exchange current (reverse INCX), intracellular Ca2+ ([Ca2+]i) levels and contractile shortening in rabbit isolated ventricular myocytes. Ouabain (0.1-8 μ m) markedly increased INaL and reverse INCX in a concentration-dependent manner, with significant effects at concentrations as low as 0.5 and 1 μ m. These effects of ouabain were suppressed by the INaL inhibitors TTX and ranolazine, the protein kinase C inhibitor bisindolylmaleimide and the Ca2+-calmodulin-dependent protein kinase II inhibitor KN-93. The enhancement by 0.5 μ m ouabain of ventricular myocyte contractility and intracellular Ca2+ transients was suppressed by 2.0 μ m TTX. We conclude that ouabain, even at low concentrations (0.5-8.0 μ m), can increase INaL and reverse INCX, and these effects may contribute to the effect of the glycoside to increase Ca2+ transients and contractility. Both protein kinase C and Ca2+-calmodulin-dependent protein kinase II activities may mediate or modulate these processes. [ABSTRACT FROM AUTHOR]

The combination of CuSO4 with naturally occurring sucrose in a biodegradable aqueous solution of PEG-200 has been confirmed as a novel, recyclable, and environmentally benign homogeneous catalyst system for the direct amination of aryl halides with NH3 ·H2O. Electron-rich, electron-poor, and even ortho-substituted aryl bromides and iodides could be aminated to provide the desired primary arylamines in high yields at 90 °C without the need of an inert atmosphere. [ABSTRACT FROM AUTHOR]

The current study was conducted to explore the effects of dietary Clostridium butyricum (C. butyricum) and fermented calcium (Ca) butyrate produced by C. butyricum on the performance and egg quality of post‐peak laying. A total of 384 50‐week‐old hens were fed a basal diet, the basal diet with 300 mg/kg of fermented Ca butyrate or 1 × 109 CFU/kg C. butyricum for 8 weeks. Hens received a C. butyricum exhibited higher yolk properties, albumen height, and Haugh unit. A diet with fermented Ca butyrate or C. butyricum increased the egg mass and the pre‐grade yellow follicle number. RNA‐sequencing (RNA‐seq) data showed that these observations were associated with cytokine–cytokine receptor interaction and intestinal immune status. Accordingly, when compared with the basal diet group, Ca butyrate and C. butyricum addition decreased serum pro‐inflammatory cytokine levels and increased the concentration of immunoglobulin A, along with improved intestinal barrier. In addition, dietary C. butyricum inclusion induced a higher abundance of Ruminococcaceae and Lachnospiraceae at the family level. In summary, dietary fermented Ca butyrate or C. butyricum supplementation improved egg quality and ovarian function, which might be related to the enhanced intestinal barrier and immunity in post‐peak laying hens. [ABSTRACT FROM AUTHOR]

A numerical method is proposed to evaluate the effect of non‐Gaussian roughness on point contact elastohydrodynamic lubrication (EHL). A mixed EHL model of point contact, considering non‐Gaussian roughness, is developed. The oil film pressure in the model was controlled by the Reynolds equation of average flow, and the contact pressure of asperity was obtained by the rough surface micro‐contact model. The influence of non‐Gaussian roughness parameters on contact pressure distribution, film thickness profile and the ratio of asperity pressure to contact load (asperity load ratio) are investigated based on the mixed EHL model. The results show that the asperity pressure increases as root mean square (RMS) roughness increases, skewness and kurtosis. The film thickness also increases with RMS roughness and skewness, but is not sensitive to kurtosis. [ABSTRACT FROM AUTHOR]

Aim: To investigate the detectability of noninvasive prenatal screening (NIPS) with conventional sequencing depth to detect fetal copy number variants. Methods: We performed a retrospective study in a total of 19 144 pregnant women. Their cell‐free plasma DNA were assessed for trisomy 21, trisomy 18, trisomy 13, sex chromosome aneuploidies, and genome‐wide copy number variants by NIPS at conventional sequencing depth. Results: Three hundred seventy‐four cases (2.0%, 374/19 144) with abnormal results were detected, which including 84 cases (0.4%, 84/19 144) with high risk of trisomy 21, 18, and 13, 90 cases (0.5%, 90/19 144) with high risk of sex chromosome abnormalities (SCA), and 44 cases (0.2%, 44/19 144) with high risk of other chromosome aneuploidies. One hundred fifty‐six cases (0.8%, 156/19 144) with high risk of copy number variations (CNVs) were also detected. In following prenatal diagnosis, composite positive predictive value (PPV) of trisomy 21, 18, and 13 was 69.6% (48/69). The PPV of SCAs was 37.3% (19/51). And the PPVs for CNVs was detected as 51.0% (<5 Mb), 71.4% (5 Mb ≤ CNV ≤10 Mb), 56.5% (>10 Mb). Finally, a follow‐up about the pregnancy outcomes were conducted for all available cases. Conclusions: NIPS yielded high PPVs for trisomy 21, 18, and 13 aneuploidies and moderate PPVs for SCAs and CNVs. The screening effectiveness was closely related to the size of CNV fragments. Larger CNVs, especially larger than 5 Mb, could be detected more accurately by NIPS in our analytic technique. Meanwhile, diagnostic confirmation by microarray analysis was highly recommended. [ABSTRACT FROM AUTHOR]

The title indoles are prepared under environmentally friendly conditions via reaction of indoles, aldehydes, and malononitrile in good to excellent yields. [ABSTRACT FROM AUTHOR]

Background: The incidence of inborn errors of metabolism (IEM) varies across countries and areas. Currently, there are no studies on IEM using newborn screening (NBS) in eastern coastal areas of China. We aimed to estimate the incidence and genetic variants of IEM and understand the spectrum of diseases caused by IEM and variants among them in this area. Methods: The NBS performed by tandem mass spectrometry (MS/MS) from 2016 to 2021 was retrospectively reviewed. Heel blood was collected from all newborns 72 h after birth. Targeted massively parallel sequencing was performed for genetic analysis. Results: Among 245,194 newborns, 95 were diagnosed with IEM, the overall incidence observed was—IEM: 1/2581; amino acid metabolism disorder: 1/4715; organic acid metabolism disorder: 1/11676; and fatty acid metabolism disorder: 1/11145. The incidence of different IEM was in the range of 1/245194 to 1/6452. Phenylketonuria (PKU, 1/7211) was the most common IEM, followed by methylmalonic acidemia (MMA, 1/27244), short‐chain acyl‐CoA dehydrogenase deficiency (SCADD, 1/30649), and citrin deficiency (CD, 1/35028). For genetic variants, the common hotspot variants found were—PAH gene for PKU: c.728G > A, c.442‐1G > A, c.611A > G, c.721C > T; PTS gene for non‐classical PKU: c.259C > T; MMACHC gene for MMA: c.658_660delAAG, c.609G > A; MMUT gene for MMA: c.1663G > A; ACADS gene for SCADD: c.1031A > G and c.1130C > T; and SLC25A13 gene for CD: c.1638_1660dup, c.852_855del. Conclusion: This study displayed the diseases and varied spectrum of IEM in eastern coastal areas of China. Implementing NBS for IEM by MS/MS combined with massively parallel sequencing can offer an improved plan for NBS to detect IEM. [ABSTRACT FROM AUTHOR]

A novel and environmentally benign homogeneous catalyst system is developed and used for the direct amination of aryl halides with ammonia consisting of naturally occurring sucrose and CuSO4 in an aqueous solution of PEG-200. [ABSTRACT FROM AUTHOR]

The title reaction provides syn,anti-Michael adducts with good diastereoselectivity (determined for crude mixtures) and excellent enantioselectivity. [ABSTRACT FROM AUTHOR]

BACKGROUND The objectives of this study were to: (1) observe the effects of drought stress ( DS) on the structural development of endosperm starch granules; (2) investigate the effects of DS on composition and physicochemical properties of starches; and (3) compare the different responses to DS between soft and hard wheat. RESULTS DS resulted in large A-type starch granules at 12 d after anthesis ( DAA) and a high percentage of B-type starch granules at 18 DAA in endosperm cells of the two wheat cultivars. DS decreased the 1000-grain weight, total starch and amylose contents, and amylose-to-amylopectin ratio of both starches. DS also decreased the percentage of B-type starch granules in NM13 and increased the number of hollows on the surface of A-type starch granules in XM33. DS further increased the swelling power and affected pasting properties of both starches. DS also significantly enhanced the hydrolysis degrees of starches by pancreatic α-amylase, Aspergillus niger amyloglucosidase, and HCl in NM13. DS altered the contents of rapidly digestible, slowly digestible, and resistant starches in native, gelatinised, and retrograded starches. CONCLUSION Overall, DS can affect the development of endosperm starch granules and the physicochemical properties of starches, thus affecting the qualities of the final wheat products. © 2015 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Serine racemase (SR) is a pyridoxal 5′-phosphate (PLP)-dependent enzyme that is responsible for d-serine biosynthesis in vivo. The first X-ray crystal structure of maize SR was determined to 2.1 Å resolution and PLP binding was confirmed in solution by UV-Vis absorption spectrometry. Maize SR belongs to the type II PLP-dependent enzymes and differs from the SR of a vancomycin-resistant bacterium. The PLP is bound to each monomer by forming a Schiff base with Lys67. Structural comparison with rat and fission yeast SRs reveals a similar arrangement of active-site residues but a different orientation of the C-terminal helix. [ABSTRACT FROM AUTHOR]

The development of highly efficient metal‐free carbon electrocatalysts for the oxygen reduction reaction (ORR) is one very promising strategy for the exploitation and commercialization of renewable and clean energy, but this still remains a significant challenge. Herein, we demonstrate a facile approach to prepare three‐dimensional (3D) N‐doped carbon with a sp3/sp2 carbon interface derived from ionic liquids via a simple pyrolysis process. The tunable hybrid sp3 and sp2 carbon composition and pore structures stem from the transformation of ionic liquids to polymerized organics and introduction of a Co metal salt. Through tuning both composition and pores, the 3D N‐doped nanocarbon with a high sp3/sp2 carbon ratio on the surface exhibits a superior electrocatalytic performance for the ORR compared to that of the commercial Pt/C in Zn–air batteries. Density functional theory calculations suggest that the improved ORR performance can be ascribed to the existence of N dopants at the sp3/sp2 carbon interface, which can lower the theoretical overpotential of the ORR. [ABSTRACT FROM AUTHOR]

The development of highly efficient metal‐free carbon electrocatalysts for the oxygen reduction reaction (ORR) is one very promising strategy for the exploitation and commercialization of renewable and clean energy, but this still remains a significant challenge. Herein, we demonstrate a facile approach to prepare three‐dimensional (3D) N‐doped carbon with a sp3/sp2 carbon interface derived from ionic liquids via a simple pyrolysis process. The tunable hybrid sp3 and sp2 carbon composition and pore structures stem from the transformation of ionic liquids to polymerized organics and introduction of a Co metal salt. Through tuning both composition and pores, the 3D N‐doped nanocarbon with a high sp3/sp2 carbon ratio on the surface exhibits a superior electrocatalytic performance for the ORR compared to that of the commercial Pt/C in Zn–air batteries. Density functional theory calculations suggest that the improved ORR performance can be ascribed to the existence of N dopants at the sp3/sp2 carbon interface, which can lower the theoretical overpotential of the ORR. [ABSTRACT FROM AUTHOR]

Abstract: Five iridoid glycosides were prepared using molecularly imprinted solid‐phase extraction combined with preparative high‐performance liquid chromatography. Hydrophilic molecularly imprinted polymers were synthesized using α‐1‐allyl‐2‐N‐acetyl glucosamine, which introduced an abundance of hydrophilic groups into the polymers. Using molecularly imprinted solid‐phase extraction as the sample pretreatment procedure, five iridoid glycosides, gardenoside, geniposide, shanzhiside, geniposidic acid, and genipin‐1‐O‐gentiobioside, were selectively enriched from Gardenia fructus extracts. Preparative high‐performance liquid chromatography then provided iridoid glycosides with a purity >98%. The structures were elucidated by using nuclear magnetic resonance spectroscopy, optical rotation and melting point measurements, and mass spectrometry. The results demonstrate that molecularly imprinted solid‐phase extraction combined with preparative high‐performance liquid chromatography was an efficient, rapid, and economical method for the preparation of bioactive compounds from natural products. [ABSTRACT FROM AUTHOR]