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Primary water and oxygen isotope composition are important tools in tracing magma source and evolution. Metamictization of zircon due to U-Th radioactive decay may introduce external secondary water to the crystal, thereby masking the primary water and oxygen isotope signature. Recently, Raman-based screening has been established to select the low-degree metamict zircons. However, such an approach may not be appropriate for ancient samples, in which nearly all zircons are metamict. It was reported that thermal annealing can potentially heal crystals and retrieve primary water content and δ18O information from metamict zircons, given the weaker hydrogen bond of secondary water than that of primary water. Heating experiments at temperatures of 200–1000 °C over a period of 2–10 h reveal that annealing can effectively recover primary water and oxygen isotopes from metamict zircons. Primary water in crystalline and metamict zircons remains intact when heated at 4 h, which represent the optimal annealing treatment condition. Hydrothermally altered zircon is an exception. It only yields the minimum estimate of its primary water contents at 600 °C over a period of >4 h, probably due to partial primary water loss during metamictization for hydrothermal zircons. Moreover, the proportion of low-δ18O (700 °C. This study therefore provides the basis for applying zircon water and δ18O proxies to geologically ancient samples.

Eocene mafic magmatism in the Himalaya provides a crucial window for probing the evolution of crustal anatexis processes within the lower plate in a collisional orogen. We report geochemical data from the earliest postcollision ocean-island basalt–like mafic dikes intruding the Tethyan Himalaya near the northern edge of the colliding Indian plate. These dikes occurred coeval, and spatially overlap, with Eocene granitoids in the cores of gneiss domes and were likely derived from interaction between melts from the lithosphere-asthenosphere boundary and the Indian continental lithosphere. We propose that these mafic magmas were emplaced along lithospheric fractures in response to lithospheric flexure during initial subduction of the Indian continent and that the underplating of such mafic magmas resulted in orogen-parallel crustal anatexis within the Indian continent. This mechanism can explain the formation of coeval magmatism and the geologic evolution of a collisional orogen on both sides of the suture zone.

Water in Earth’s deep mantle may have been acquired early1−7, when deep magma oceans that extend to Earth’s lower mantle, possibly to the core-mantle boundary, were prevalent in the aftermath of energetic impacts8,9. However, how early water was retained and distributed during crystallization of magma oceans remains unclear. This is primarily determined by partitioning of water between mantle mineral and silicate melt. Bridgmanite is the first and dominant mineral crystallized from deep magma oceans10. Yet early attempts are restricted to bridgmanite at the topmost lower mantle condition or minerals in the upper mantle and transition zone11. Here we use laser-heated diamond anvil cell to simulate relevant magma ocean conditions and investigate partitioning of water between bridgmanite and melt. Our data show that partitioning of water in bridgmanite over silicate melt is significantly higher than previous estimates and strongly dependent on temperature. Given plausible magma ocean crystallization scenarios, appreciable amounts of water may be retained in the lower mantle following the crystallization of a deep magma ocean. Circulation of such early, deep, and likely primordial water in Earth’s interior could modulate mantle dynamics and facilitate the transition of early Earth to a habitable planet.

Water content and oxygen isotopes in zircon provide crucial constraints on magma source and process, yet they can be significantly modified by zircon metamictization, which causes secondary water absorption into the zircon crystal and the concomitant oxygen isotope changes. Therefore, it is imperative to develop a screening scheme to select the least-metamict zircons for the analyses. We propose a screening scheme based on our study on the Suzhou A-type granite (South China) through integrating Raman spectroscopy, water and trace element measurements, and oxygen isotope analysis. The results show that the primary water content is retained in zircon when the full-width at half maximum (FWHM) is 1007 cm−1 of ν3(SiO4) vibration band, while the primary δ18O is preserved at 1005.5 cm−1 Raman shift. Changes in trace element concentrations in Suzhou zircons are different from previous observations in metamict zircons but most likely related to magma evolution, which implies that trace elements are insensitive to metamictization. Primary δ18O in Suzhou zircons (4.5–6.0‰) fall into the mantle range, indicating a dominant mantle contribution to Suzhou granites. Primary water content was estimated at ca. 650–1400 ppm, significantly higher than those of typical I-type granite (400–736 ppm) and upper mantle-derived zircons (81–177 ppm). The high primary zircon water content was not controlled by the sub-solidus process, temperature, pressure, and cation charge balance but considered to reflect the high-water content in melts. This suggests a hydrous origin for the Suzhou A-type granite, which challenges the conventional view of anhydrous petrogenesis for A-type granites.

The topographic transition of central–northern Tibet since the early Miocene has created a consistently high and flat plateau similar to that of today. However, to date, the associated deep crust and/or /mantle events are poorly understood, mainly due to an early Miocene metamorphic–magmatic lull within the Qiangtang Block. To address this issue, we undertook a study of crustal xenoliths and zircon xenocrysts in 6.0–2.3 Ma lavas in the Qiangtang Block. The occurrence of 22.6–12.9 Ma high-temperature–low-pressure granulite xenoliths implies that the middle crust of the block has been very hot since that time. Zircon xenocrysts and granitic xenoliths from 6.0–2.3 Ma lavas were studied and shown to have high δ18O values, which supports Miocene crustal melting and the formation of unexposed, coeval felsic plutons. Combined with paleoelevation data from the Tibetan Plateau, our results suggest that the early Miocene cold–hot thermal transition of the middle–lower crust was near-synchronous with topographic evolution from high-relief mountains to a flat plateau, which supports crustal flow as the main topographic smoothing mechanism for central–northern Tibet.

The formation of post-collisional mantle-derived rocks in the Tibetan Plateau has been linked to the deep geodynamic processes that cause surface uplift. Co-existing silica-oversaturated to silica-undersaturated mantle-derived rocks have been identified in the northern Qiangtang Terrane (NQT). However, the origins of silica-undersaturated magmas are controversial, and the mechanisms responsible for variable silica activity in the mantle-derived rocks are unclear. Here, we present 40Ar/39Ar chronology, mineral chemistry, and whole-rock geochemical data for the Bamaoqiongzong (BMQZ) volcanic rocks of the NQT. The BMQZ volcanic rocks consist of olivine leucitites, trachybasalts, and phonolites and were erupted at ca. 29 Ma. All samples are unsaturated in silica and characterized by enrichment in light rare earth elements and large-ion lithophile elements, depletion in high-field-strength elements, and the presence of negative Nb–Ta–Ti anomalies and positive Pb anomalies. All samples show limited variation in (87Sr/86Sr)i (0.7079–0.7085) and εNd(t) values (−6.9 to −5.3). The geochemical compositions of the BMQZ volcanic rocks indicate that they were produced by partial melting of carbonated phlogopite–lherzolite within the lithospheric mantle. The formation of the olivine leucitites-trachybasalts-phonolites suite was controlled by fractional crystallization and magma mixing in a magmatic plumbing system. This plumbing system included several independent reservoirs and conduits within the crust. The enriched mantle sources of the BMQZ volcanic rocks were formed by the addition of carbonate-rich melts released from the southward-subducted Songpan–Ganzi Terrane after the Late Cretaceous. Our new results, together with published data, reveal systematic variations in geochemical compositions between silica-undersaturated and silica-oversaturated rocks in the NQT, which are ascribed to variations in the nature of the subducted continental materials added during intracontinental subduction. Carbonate-rich melts that were formed by the breakdown of carbonate minerals helped to generate the mantle sources of silica-undersaturated rocks, whereas silicate melts produced by the partial melting of sediment diapirs contributed to the generation of the silica-oversaturated rocks. On the basis of published numerical modelling of continental subduction and crustal deformation records in the NQT, we suggest that intracontinental subduction and lithospheric thinning together contributed to the generation of post-collisional mantle-derived rocks in the Tibetan Plateau.

Eight new arnebinol B-based meroterpenoids ((-)-1, 2, 3, (-)-5, and 7-10) with a constrained 6/10/5 tricyclic backbone were isolated from the roots of Arnebia euchroma. The planar and steric structures of these new compounds were unambiguously elucidated by extensive spectroscopic analyses, X-ray diffraction crystallography, and ECD calculations. The predominant relative orientation between H-7 and the Z double bond with a methyl substituent in the rigid 10-membered carbocycle, along with the planar chirality of the Z double bond was analyzed and discussed for the first time. The illustration of the planar chirality derived from the Z double bond should be paid great importance during the structure elucidation on these homologous meroterpenoids. All the isolated meroterpenoids were screened for their cytotoxicities against the HCT-8, PANC-1, HGC-27, HepG2, and PC9 cell lines, and compounds (+)-5 and (-)-5 exhibited the most potent cytotoxicity.

Understanding the subduction and recycling of continental crust is crucial for reconstructing the long-term evolutionary history of Earth's mantle and crust. The Himalaya-Tibet orogen is arguably the world's best natural laboratory for investigating these processes. Cenozoic post-collisional ultrapotassic volcanic rocks are common in the Lhasa block of southern Tibet and they can provide important clues to crust-mantle interaction in a well-characterized continental collision zone. Understanding the sources and processes that generated these lavas can contribute to our understanding of the thermal and compositional characteristics of the deep mantle and geodynamic processes in this region, including Indian continental subduction. In this contribution, we report Sr-Nd-Pb-O-B isotope and elemental chemistry data for post-collisional (13-11 Ma) ultrapotassic rocks from the TangraYumco-Xuruco rift (TYXR) in the Lhasa block. The arc-like trace-element signatures and markedly enriched Sr-Nd-Pb-O isotope compositions indicate that these mafic rocks originate from a mantle source containing recycled crustal components. Unlike pre-collisional (∼64 Ma) ultrapotassic rocks in the Lhasa block with arc-like B/Nb (0.85-1.89) and B (−9.0 to −2.5‰) values, the TYXR post-collisional ultrapotassic rocks with much lower B/Nb (0.05-0.85) and B (down to −20.5‰) values resemble Miocene K-rich volcanic rocks from western Anatolia. These western Anatolian rocks have been formed by either progressive dehydration of a stalled slab or deep-subducted continental crust. However, some TYXR samples have lower B/Nb ratios than MORB, consistent with a fluid-starved source. These markedly negative B in conjunction with low B/Nb cannot be explained by the addition of melts from oceanic sediments, which generally yield lower B/Nb but higher B values than MORB (e.g., the Armenia post-collisional mafic rocks). Given the low B of Indian upper continental crust and its similar Sr-Nd-Pb isotopic signatures to the post-collisional lavas, it is clear that the post-collisional ultrapotassic rocks in the Lhasa block contain a significant component derived from subducted Indian continental crust. Combined with the temporal evolution of regional magmatism, tectonics and geophysical data, we propose that the break-off and tearing of subducted Indian continental slab induced post-collisional magmatism in the Lhasa block. Our case study provides evidence that continental subduction contributes to very light B isotope compositions of post-collisional magmas, which suggests that B isotopes have the potential to discriminate between oceanic subduction and continental subduction.

One pair of new amides enantiomers (1a and 1b) and two known amides were isolated from the rhizomes of Polygonum cuspidatum. Their structures were established using UV, IR, HRESIMS, and NMR data. Notably, compound 1 possesses unique C-C connection between feruloyltyramine and resveratrol. Their absolute configurations were determined by the ECD method. All compounds were evaluated for their α-glucosidase inhibitory activity and compounds 2 and 3 showed significant inhibitory activity with IC50 values of 2.82 and 13.06 μmol/L, respectively (positive control acarbose, IC50 385 μmol/L).

A concise method was established to determine the relative and absolute configurations of aryl-glycerols that depend on the chemical shift differences (Δδ) of the diastereotopic methylene protons (H-3) by 1H NMR spectroscopy. When using DMSO-d6 as the preferred solvent, the threo configuration corresponded to a larger ΔδH3a–H3b value (>0.15 ppm), whereas the erythro configuration ( 0.20 ppm. In the erythro enantiomers, the Δδ value of 1R,2S was >0.09 ppm, and that of 1S,2R was

New phloroglucinol glycosides, aglycones, and oxidative dearomatized products of aglycones were discovered from Agrimonia pilosa, and the mechanism of the auto oxidative dearomatization was disclosed as a free radical chain reaction with 3O2.

Sepsis is identified as a severe inflammatory disease. Epigallocatechin-3-gallate (EGCG) has been reported to be a powerful anti-inflammatory chemical substance in numerous diseases. However, the underlying mechanism of the anti-inflammatory effects of EGCG in sepsis remains to be elucidated.The surgery for cecal ligation and puncture (CLP) was performed on male C57BL/6J mice aged 8 weeks. THP-1 cells were treated with 1 μg/ml lipopolysaccharide (LPS) for 24 h to imitate sepsis in vitro. Haematoxylene-Eosin (HE) staining of the sections of liver, lung and kidney was performed to evaluate the pathological changes. The inflammatory cytokines were quantitated by ELISA. qRT-PCR was performed to measure the expression levels of PVT1, miR-16-5p, and TLR4. The protein level of TLR4 was also assessed by Western blotting. Double luciferase reporter assay and RIP assay were performed to validate the interactions among PVT1, miR-16-5p, and TLR4.EGCG inhibited the expression levels of PVT1 and TLR4 and enhanced miR-16-5p expression in CLP-operated mice and LPS-treated THP-1 cells. EGCG reduced the levels of inflammatory cytokines, which were restored by PVT1 overexpression. Mechanistically, PVT1 bound with miR-16-5p to activate TLR4 signaling. Further experiments demonstrated that miR-16-5p silencing or TLR4 overexpression antagonized sh-PVT1 or miR-16-5p mimics-mediated inhibitory effects on inflammatory cytokines, respectively. Knockdown of PVT1 alleviated inflammatory injury in CLP-induced sepsis in mice.EGCG may effectively lower the levels of sepsis-induced inflammatory cytokines by targeting the PVT1/miR-16-5p/TLR4 axis.

Three new monocyclic monoterpenoid containing β-D-apiofuranosyl-(1→2)-O-β-D-glucopyranosyl moieties, together with three other known monocyclic monoterpenoid O-glycosides, were obtained from the roots of Glycyrrhiza uralensis for the first time. Their structures were determined by UV, IR, HRESIMS, and 1D and 2D NMR data.

Lithium garnets have been widely studied as promising electrolytes that could enable the next-generation all-solid-state lithium batteries. However, upon exposure to atmospheric moisture and carbon dioxide, insulating lithium carbonate forms on the surface and deteriorates the interfaces within electrodes. Here, we report a scalable solid sintering method, defined by lithium donor reaction that allows for complete decarbonation of Li6.4La3Zr1.4Ta0.6O12 (LLZTO) and yields an active LiCoO2 layer for each garnet particle. The obtained LiCoO2 coated garnets composite is stable against air without any Li2CO3. Once working in a solid-state lithium battery, the LiCoO2-LLZTO@LiCoO2 composite cathode maintains 81% of the initial capacity after 180 cycles at 0.1 C. Eliminating CO2 evolution above 4.0 V is confirmed experimentally after transforming Li2CO3 into LiCoO2. These results indicate that Li2CO3 is no longer an obstacle, but a trigger of the intimate solid-solid interface. This strategy has been extended to develop a series of LLZTO@active layer materials., Formation of insulating lithium carbonate on surface of lithium garnets hinders their application as solid electrolyte in lithium ion batteries. Here the authors explore a scalable sintering approach to utilize the undesired Li2CO3 and improve the active material-electrolyte interface within cathodes.

Dense and submicron-sized polycrystalline β-Si3N4 bulk samples with average grain size of 263 ± 68 nm have been synthesized using micron-sized α-Si3N4 powder (2 μm) as the starting material by simultaneously tuning the pressure and temperature conditions. The measured Vickers hardness HV of the submicron-sized polycrystalline β-Si3N4 could reach up to about 20 GPa, approaching the upper limit of the single crystal β-Si3N4. The measured fracture toughness KIC of the polycrystalline β-Si3N4 has been enhanced from 3.0 to 4.1 MPa m1/2, as much as 36%, while without sacrificing the hardness. This study demonstrates that using micron-sized powder as the starting material to synthesize submicron-sized polycrystalline bulks by phase transformation under extreme pressure conditions is an efficient pathway to break through the old paradigm—the higher the fracture toughness of a material, the lower the hardness.

Significance Reconstructing past extreme weather events, such as tropical cyclones and cold surges, using natural paleoclimate archives can lengthen the instrumental data and help us have a broader understanding of the range of weather variability not evident in instrumental record. However, the time resolution of current paleoarchives, from millennial to monthly at best, is usually too low to explore past weather events. Here we found that the Tridacna shells from South China Sea, western Pacific, have continuous daily growth bands, and several daily to hourly resolution biogeochemical proxy records were developed. Our results demonstrate that these records can record nearby tropical cyclones and cold surges, indicating that Tridacna shells have the potential to be an unprecedented ultra-high-resolution archive for paleoweather reconstructions., Paleoclimate research has built a framework for Earth’s climate changes over the past 65 million years or even longer. However, our knowledge of weather-timescale extreme events (WEEs, also named paleoweather), which usually occur over several days or hours, under different climate regimes is almost blank because current paleoclimatic records rarely provide information with temporal resolution shorter than monthly scale. Here we show that giant clam shells (Tridacna spp.) from the tropical western Pacific have clear daily growth bands, and several 2-y-long (from January 29, 2012 to December 9, 2013) daily to hourly resolution biological and geochemical records, including daily growth rate, hourly elements/Ca ratios, and fluorescence intensity, were obtained. We found that the pulsed changes of these ultra-high-resolution proxy records clearly matched with the typical instrumental WEEs, for example, tropical cyclones during the summer−autumn and cold surges during the winter. When a tropical cyclone passes through or approaches the sampling site, the growth rate of Tridacna shell decreases abruptly due to the bad weather. Meanwhile, enhanced vertical mixing brings nutrient-enriched subsurface water to the surface, resulting in a high Fe/Ca ratio and strong fluorescence intensity (induced by phytoplankton bloom) in the shell. Our results demonstrate that Tridacna shell has the potential to be used as an ultra-high-resolution archive for paleoweather reconstructions. The fossil shells living in different geological times can be built as a Geological Weather Station network to lengthen the modern instrumental data and investigate the WEEs under various climate conditions.

One new tanshinone derivative, which possesses an unusual 6/6/5/6 fused-ring skeleton system (1), together with four new five-membered lactone benzohexa-membered ring compounds (2, 3, 4A and 4B), and three new carboxyl substituted 5,5-spiroketal compounds (5–7), were isolated from the dried rhizomes of Salvia miltiorrhiza. The structures of these compounds were determined by multiple spectral analyses (UV, IR, NMR, and HR-ESI-MS). In addition, the absolute configurations were established by X-ray diffraction experiments, calculated and experimental circular dichroism spectra. Evaluation of antitumor activity showed that 1 had strong cytotoxicity to tumor-repopulating cells (TRCs) with an IC50 value of 2.83 μM. In the evaluation of neuroprotective activity, 4A and 6 showed a strong improvement in the survival rates of SK-N-SH cell injury induced by oxygen glucose deprivation (OGD).

Background Modulations on gut microbiota by traditional Chinese medicines (TCMs) and their active components are emerging as potential therapeutic agents on diabetes. Litsea glutinosa is a TCM used in clinic to treat diabetes with alkaloids as the active constituents, and the Laurolitsine is the richest one. Purpose Based on that, this study was designed to identify the potential capability of Laurolitsine on alleviating Type 2 diabetes and the changes of the composition of intestinal flora related to this disease. Methods In present study, Laurolitsine was administered to diabetic mice (db/db) by daily oral gavage at doses of 50, 100 and 200 mg/kg/day for 4 weeks. The body weight, fasting blood glucose, oral glucose tolerance test (OGTT) and insulin tolerance test (ITT), lipid metabolism of serum and liver and liver function were measured to assess the anti-hyperglycemic and anti-hyperlipidemic effects of Laurolitsine. The liver pathological changes were observed by HE staining. Meanwhile, the effects of Laurolitsine on the changes of the composition of gut microbiota in mice were investigated via metagenomic analysis. Results Experimental results show that different doses of Laurolitsine have varying degrees of hypoglycemic and hypolipidemic effects. Among them, the treatment effect of 200mg·Kg-1 is the most obvious. In addition, Laurolitsine changes the structure of intestinal microflora significantly at various taxonomical levels in the diabetic db/db mice. Conclusions These results demonstrate that Laurolitsine may regulate glucose and lipid metabolism and improve diabetes through modulating intestinal microflora of Parabacteroides and Mucispirillum, which may be acknowledged as the iconic bacteria of diabetes.

Background: Compelling evidence has linked the commensal gut microbiota to human metabolic syndromes and provided new therapeutic potentials against diseases, such as hyperlipidemia. However, the precise regulatory effect of each bacterial species on human lipid homeostasis remains largely unknown.Results: We set up a cell-based high-throughput screening platform and screened 2250 human gut bacterial strains from 186 species for the lipid-decreasing activity in HepG2 cells, in which 388 strains steadily inhibited lipid accumulation. Different strains in the same species usually displayed distinct lipid-modulatory actions, revealing an obvious strain-specificity. Blautia producta, Lactobacillus gasseri, and Bifidobacterium pseudolongum contained a much higher portion of hypolipidemic strains. Among all the tested strains, the mucosal bacterium Blautia producta exhibited the most potency to suppress lipid accumulation, and gavage of live Bl. producta effectively ameliorated hyperlipidemia in mice. 12-Methylmyristic acid (12-MMA) was identified as an important active metabolite of Bl. producta by pan-genomics and comparative metabolomics, which exerted potent anti-hyperlipidemic effect in vivo and activated G protein-coupled receptor 120 (GPR120), thus stimulating white adipose tissue browning.Conclusions: Together, these data reveal a previously unreported large-scale lipid-modulatory profile of gut microbes at the strain level, and raise the possibility of developing therapeutics based on Bl. producta and microbial metabolite 12-MMA to treat hyperlipidemia.

To further reveal the active ingredients of Danshen, we systematically studied its chemical components and obtained two new lithospermic acid derivatives (compounds 1 and 2) together with five known phenylpropionic acids (compounds 3-7) from the dried rhizomes of Salvia miltiorrhiza. The structures of the two new compounds were determined by multiple spectral analyses (UV, IR, HR-ESI-MS, NMR, and ECD). In addition, the absolute configurations were established by chiral analysis and calculated and experimental circular dichroism spectra. Biological research indicated that compound 1 could significantly inhibit the proliferation of isoproterenol (ISO)-treated cardiac fibroblasts (AC16 cells), and MMP9 was found to be the most likely target of compound 1. The protein expression and mRNA levels of MMP9 were increased in ISO-induced AC16 cells, which could be reversed by treatment with compound 1. Furthermore, this treatment could alleviate the migration and activation of ISO-induced cardiac fibroblasts.

Background: Jianpi-Qushi-Heluo formula (JQHF) has been used to treat idiopathic membranous nephropathy (IMN) in hospitals for many years. Purpose: Elucidating the protective effect and exploring the potential mechanism of JQHF against IMN. Methods: Passive Heymann nephritis (PHN) was induced in rats by a single tail vein injection of anti-Fx1A antiserum. Then, the animals were treated with JQHF at 16.2 g/kg or 32.4 g/kg, with benzepril (10 mg/kg) as a positive control. Renal function was evaluated by biochemical measurements and pathological testing. Fecal samples were collected before and after treatment to analyze the gut microbiota composition by shotgun whole metagenome sequencing. Results: JQHF exhibited potent efficacy in ameliorating PHN at both doses, as revealed by decreasing the deposition of IgG and C5b-9, relieving podocyte injury, and reducing glomerular and tubular cell apoptosis. The lower dose was corresponding to the clinical dosage and showed better therapeutic effects than the higher dose. Metagenomic analysis showed that gavage with 16.2 g/kg of JQHF shifted the structure of the gut microbiota in PHN rats and significantly increased the relative abundances of Prevotella copri, Lactobacillus vaginalis and Subdoligranulum variabile. Particularly, S. variabile was strongly negatively correlated with serum levels of TC and TG, the deposition of IgG and C5b-9, and apoptosis of glomerular cells. Conclusions: The JQHF is an effective agent for the treatment of experimental PHN. The PHN-allevating effect of JQHF is associated with specific alternation of gut microbiota.

Lung cancer is one of the most common types of cancer, with the highest mortality rate worldwide. MicroRNAs play notable roles in the chemotherapeutic effects of anticancer drugs. The present study used reverse transcription-quantitative PCR, western blotting and cell migration and invasion assays to reveal the role of let-7f-1-3p in non-small cell lung cancer (NSCLC) and explore the effect of let-7f-1-3p on doxorubicin (DOX) treatment. It was demonstrated that the levels of let-7f-1-3p in carcinoma tissues were lower compared with those in paracarcinoma tissues. Thus, let-7f-1-3p may act as a suppressor gene. The present study also explored the role of let-7f-1-3p in A549 and NCI-H1975 cells. Results revealed that let-7f-1-3p could inhibit the viability, migration and invasion of NSCLC cells and induce their apoptosis. Integrin β1 acted as a target gene regulated by let-7f-1-3p. This suggested that let-7f-1-3p could enhance DOX-inhibited cell viability, migration and invasion in vitro. Overall, the present study demonstrated that let-7f-1-3p may act as a target for drug design and lung cancer therapy.

Background Akkermansia spp. plays important roles in maintenance of host health. Increasing evidence reveals that berberine (BBR) may exert its pharmacological effects via, at least partially, promotion of Akkermansia spp. However, how BBR stimulates Akkermansia remains largely unknown. Purpose In this study, we investigated the mechanism underlying the Akkermansia-promoting effect of BBR. Materials and methods The effect of BBR on Akkermansia was assessed in BBR-gavaged mice and direct incubation. The influence of BBR on intestinal mucin production was determined by alcian-blue staining and real-time PCR. The feces were analysis by gas chromatography–time-of-flight mass spectrometry (GC-TOF/MS) metabolomics. The role of polyamines in BBR-elicited mucin secretion and Akkermansia growth was evaluated by administration of difluoromethylornithine (DFMO) in mice. Results Gavage of BBR dose-dependently and time-dependently increased the abundance of Akkermansia in mice. However, it did not stimulate Akkermansia growth in direct incubation, suggesting that BBR may promote Akkermansia in a host-dependent way. Oral administration of BBR significantly increased the transcription of mucin-producing genes and mucin secretion in colon. Untargeted metabolomics analysis showed that BBR increased polyamines production in feces which are known to stimulate goblet cell proliferation and differentiation, but treatment with eukaryotic polyamine synthase inhibitor DFMO did not abolish the stimulating effect of BBR on mucin secretion and Akkermansia growth, indicating that the gut bacteria-derived but not the host-derived polyamines may involve in the BBR-promoted Akkermansia growth. Conclusions Our results reveal that BBR is a promising prebiotic for Akkermansia, and it promotes Akkermansia growth via stimulating mucin secretion in colon.

Characterization of the bacterial composition and functional repertoires of microbiome samples is the most common application of metagenomics. Although deep whole-metagenome shotgun sequencing (WMS) provides high taxonomic resolution, it is generally cost-prohibitive for large longitudinal investigations. Until now, 16S rRNA gene amplicon sequencing (16S) has been the most widely used approach and usually cooperates with WMS to achieve cost-efficiency. However, the accuracy of 16S results and its consistency with WMS data have not been fully elaborated, especially by complicated microbiomes with defined compositional information. Here, we constructed two complex artificial microbiomes, which comprised more than 60 human gut bacterial species with even or varied abundance. Utilizing real fecal samples and mock communities, we provided solid evidence demonstrating that 16S results were of poor consistency with WMS data, and its accuracy was not satisfactory. In contrast, shallow whole-metagenome shotgun sequencing (shallow WMS, S-WMS) with a sequencing depth of 1 Gb provided outputs that highly resembled WMS data at both genus and species levels and presented much higher accuracy taxonomic assignments and functional predictions than 16S, thereby representing a better and cost-efficient alternative to 16S for large-scale microbiome studies.

In the burgeoning microbiome field, powerful sequencing approaches and accompanied bioanalytical methods have made tremendous contributions to the discoveries of breakthroughs, which favor to unravel the intimate interplay between gut microbiota and human health. The proper preservation of samples before being processed is essential to guarantee the authenticity and reliability of microbiome studies. Hence, the development of preservation methods is extremely important to hold samples eligible for the consequent analysis, especially population cohort-based investigations or those spanning species or geography, which frequently facing difficulties in suppling freezing conditions. Although there are several commercial products available, the exploration of cost-efficient and ready-to-use preservation methods are still in a large demand. Here, we performed shotgun metagenomic sequencing and demonstrated that microbial consortia in human fecal samples were substantially preserved within a temporary storage of 4 h, independent of the storage temperature. We also verified a previous reported self-made preservation buffer (PB buffer) could not only preserve fecal microbiota at room temperature up to 4 weeks but also enable samples to endure a high temperature condition which mimics temperature variations in summer logistics. Moreover, PB buffer exhibited suitability for human saliva as well. Collectively, PB buffer may be a valuable choice to stabilize samples if neither freezing facilities nor liquid nitrogen is available.

Six methyl-substituted phloroglucinol glycosides (1-6) were isolated from

The determination of molecular configuration is usually a difficult and key point in the structure elucidation of natural products. However, due to the small number of available samples and the multiple chiral centers and complex structures of natural products, it is difficult to rapidly and accurately determine their relative configurations. In this paper, we use an NMR technique to comprehensively study 8,4′-oxyneolignan glucosides and find that the chemical shift difference between H-9a and H-9b can be used to accurately and rapidly determine the relative configuration of H-7 and H-8. Our finding can be directly applied to 8,4′-oxyneolignan glucosides without the need for hydrolysis.

Saffloneoside (1), a structurally unusual p-hydroxycinnamylcyclopentenone C-glucoside obtained from the florets of Carthamus tinctorius, was synthesized on a gram scale in seven steps. A stereospecific acyloin ring contraction controlled by the chirality of glucose moiety at the C5 position of highly substituted cyclohexadienones was discovered. The possible β-orientation hydrogen migration mechanism in the transformation of C5(sp2) into C5(sp3) was proposed.