Mesoporous Activated Biochar from Crab Shell with Enhanced Adsorption Performance for Tetracycline.

In this study, three mesoporous-activated crab shell biochars were prepared by carbonation and chemical activation with KOH (K-CSB), H3PO4 (P-CSB), and KMnO4 (M-CSB) to evaluate their tetracycline (TC) adsorption capacities. Characterization by SEM and a porosity analysis revealed that the K-CSB, P-CSB, and M-CSB possessed a puffy, mesoporous structure, with K-CSB exhibiting a larger specific surface area (1738 m2/g). FT-IR analysis revealed that abundant, surface ox-containing functional groups possessed by K-CSB, P-CSB, and M-CSB, such as -OH, C-O, and C=O, enhanced adsorption for TC, thereby enhancing their adsorption efficiency for TC. The maximum TC adsorption capacities of the K-CSB, P-CSB, and M-CSB were 380.92, 331.53, and 281.38 mg/g, respectively. The adsorption isotherms and kinetics data of the three TC adsorbents fit the Langmuir and pseudo-second-order model. The adsorption mechanism involved aperture filling, hydrogen bonding, electrostatic action, π-π EDA action, and complexation. As a low-cost and highly effective adsorbent for antibiotic wastewater treatment, activated crab shell biochar has enormous application potential.

Downregulation of hsa_circ_0004543 Activates oxLDL-Induced Vascular Endothelial Cell Proliferation and Angiogenesis.

Circular RNAs (circRNAs) are novel non-coding RNAs, which show abnormal expression in several diseases, such as atherosclerosis (AS). The purpose of the present study was to reveal the association between hsa_circ_0004543 and AS. In the present study, hsa_circ_0004543 was overexpressed in human umbilical vein endothelial cells (HUVECs) induced by oxidized low-density lipoprotein (oxLDL). Inhibition of hsa_circ_0004543 expression facilitated the proliferation, migration, and invasion of HUVECs and significantly reduced their apoptotic rate following treatment with oxLDL. Furthermore, silencing of hsa_circ_0004543 activated the PI3K/AKT/NOS3 pathway in oxLDL-induced HUVECs. Collectively, these results demonstrated that hsa_circ_0004543 may play a vital role in the development of AS and affect the proliferation of HUVECs, providing a potential target for treating endothelial cell damage in AS.

One new spirocyclic lactone and one new benzopyran derivative from Aspergillus terreus.

One new spirocyclic lactone, terreinlactone C (1), and one new benzopyran derivative, 2,2-dimethyl-3-hydroxychroman-6-aldehyde (2), were discovered from the fungus Aspergillus terreus. The chemical structures of compounds 1 and 2 were elucidated by detailedly analyzing NMR and HRESIMS data. Compound 1 is the first natural product with a 1-oxaspiro[4.5]decan-2-one ring system and a possible biogenetic pathway is proposed. Two compounds were tested for their cytotoxic activities against five human cancer cell lines.[Formula: see text].

The risk factors of new-onset atrial fibrillation after pacemaker implantation.

OBJECTIVE: The aim of this study was to determine the incidence of newly detected atrial fibrillation (AF) in patients following dual-chamber pacemaker (PPM) implantation and to define the clinical predictors of new-onset AF in a Chinese cohort. METHODS: A total of 219 patients without documented AF that underwent dual-chamber PPM implantation for sick sinus syndrome (SSS) (n = 88) or atrioventricular block (AVB) (n = 131) were prospectively studied. All patients were invited to follow-up at 1 month, 3 months and 6 months after the pacemaker implantation procedure, and once every 6 months thereafter. An atrial high-rate episode (AHRE) ≥5 min and an atrial rate ≥180 bpm was defined as AF. RESULTS: During follow-up of 884 ± 180 days, AF was detected in 56 (26%) patients. Using Kaplan-Meier survival curves with Log-rank test, SSS patients with a cumulative percentage of ventricular pacing (Cum % VP) ≥60% had a significantly higher rate of new-onset AF compared to AVB patients (p = 0.026) and SSS patients with Cum % VP <60% (p = 0.018). On multivariate Cox regression analysis, higher Cum % VP independently predicted higher morbidity of newly detected AF (hazard ratio [HR] 1.01; confidence interval [CI] 1.00 ~ 1.02; p = 0.035) among SSS patients. Larger left atrial (LA) dimension was a predictor of newly detected AF (HR 1.06; CI 1.01 ~ 1.14; p = 0.046) in AVB patients. CONCLUSION: The incidence of AF following dual-chamber PPM implantation was relatively high in this Chinese cohort. High Cum % VP and larger LA dimension could independently predict new-onset AF after dual-chamber PPM implantation in SSS and AVB patients, respectively.

SIRT3 is a downstream target of PPAR-α implicated in high glucose-induced cardiomyocyte injury in AC16 cells.

Diabetic cardiomyopathy (DCM) is a worldwide public health concern that continues to display rapid growth trends. This study investigated the function of sirtuin 3 (SIRT3), a primary mitochondrial deacetylase with important roles in antioxidant defense and oxidative metabolism, during high glucose-induced cardiomyocyte (AC16 cell) injury. Peroxisome proliferator-activated receptor-α (PPAR-α) is directly related to the occurrence of DCM. Hence, we further examined the relationship between SIRT3 and PPAR-α. AC16 cells were treated with various concentrations of glucose. Relative mRNA expression and protein levels were detected by RT-qPCR and western blot analysis, respectively. Cell proliferation and apoptosis were assessed using CCK8 and Annexin V-FITC apoptosis detection kits, respectively. DCFH-DA assay was used to measure reactive oxygen species (ROS) accumulation. The results indicated that high glucose treatment reduced the expression of mRNA and protein of SIRT3 and PPAR-α in AC16 cells. Moreover, high glucose inhibited cell proliferation, as well as induced apoptosis, intracellular hydrogen peroxide production, and JNK1/2 phosphorylation. These effects were antagonized by SIRT3 overexpression or treatment with the PPAR-α agonist, Wy14643. Conversely, inhibition of SIRT3 via 3-TYP led to similar phenomena as those induced by high glucose treatment in AC16 cells, which were blocked by Wy14643. Lastly, chromatin immunoprecipitation (ChIP) and luciferase assays demonstrated SIRT3 as a direct target of PPAR-α. Taken together, the results provide evidence for an important role of SIRT3 in high glucose-induced cardiomyocyte injury and regulation of JNK1/2 signaling. Further, SIRT3 is a direct downstream target of PPAR-α.

Dimericchalasine A and Amichalasines D and E: Unexpected Cytochalasan Homodimer and Heterotrimers from Aspergillus micronesiensis PG-1.

The study of Aspergillus micronesiensis led to the isolation of three unprecedented cytochalasans (1-3). Dimericchalasine A (1) is the first cytochalasan homodimer fused by a C-20/C-20' single bond. Amichalasines D (2) and E (3) represent a new type of cytochalasan heterotrimer with a decacyclic 5/6/11/5/5/6/5/12/6/5 ring system. Their structures were determined by extensive spectroscopic data and single-crystal X-ray diffraction. The plausible biosynthetic pathways of 1-3 were proposed.

Flavipesines A and B and Asperchalasines E-H: Cytochalasans and Merocytochalasans from Aspergillus flavipes.

Flavipesines A and B (1 and 2) and asperchalasines E-H (3-6), two cytochalasans with an unusual ring system and four merocytochalasans possessing a 5/6/11/5/5/6 ring system, were isolated from Aspergillus flavipes, along with three related compounds (7-9). Their structures, including absolute configurations, were determined on the basis of data from HRESIMS, NMR, ECD, molecular modeling, and single-crystal X-ray diffraction. Flavipesines A and B (1 and 2) represent the first examples of cytochalasans possessing a 5/6/7/6 ring system with a C-18-O-C-21 bridge. Compounds 3, 7, and 9 show moderate inhibitory activities against isocitrate dehydrogenase 1 (IDH1). This is the first report on the IDH1 inhibitory activities of cytochalasans.

Upregulation of miR-93 and inhibition of LIMK1 improve ventricular remodeling and alleviate cardiac dysfunction in rats with chronic heart failure by inhibiting RhoA/ROCK signaling pathway activation.

OBJECTIVE: There are some researches about the role of microRNA (miRNA) in chronic heart failure (CHF) were performed, but the study about miR-93's function in CHF is scarcely investigated. Thus, we determined to probe into the effects of miR-93 in rats with CHF by targeting LIMK1 through regulating RhoA/ROCK pathway. RESULTS: We found increased LIMK1 and decreased miR-93 in CHF rats, and up-regulation of miR-93 inhibited LIMK1, RhoA and ROCK1 expression in CHF rats. Up-regulation of miR-93 or inhibition of LIMK1 decreased oxidative stress, inflammatory factors, as well as apoptosis-related indicators in CHF rats. LIMK1 was confirmed as a direct target gene of miR-93. CONCLUSION: Our study provides evidence that upregulated miR-93 and downregulated LIMK1 improve ventricular remodeling and reduce cardiac dysfunction in CHF rats by inhibiting RhoA/ROCK signaling pathway activation. METHODS: First, rat models of CHF were established by aortic coarctation, and the rats were injected with miR-93 mimics, LIMK1-siRNA or overexpressed-LIMK1. Then expression of miR-93, LIMK1, RhoA, and ROCK1 expression in myocardial tissues were detected, after which indices of cardiac ultrasound, hemodynamics, and oxidative stress, inflammatory factors, apoptosis-related indicators were detected via a series of assays. Finally, the targeting relationship of miR-93 and LIMK1 was verified.

Cysteine Residue Containing Merocytochalasans and 17,18-seco-Aspochalasins from Aspergillus micronesiensis.

Two cysteine residue containing merocytochalasans (cyschalasins A and B, 1 and 2) and two 17,18-seco-aspochalasins (secochalasins A and B, 3 and 4) were isolated from the endophytic fungus Aspergillus micronesiensis. Cyschalasins A and B represent a new type of merocytochalasan featuring the fusion of an aspochalasin with a modified cysteine residue. Secochalasins A and B are the first 17,18-seco-aspochalasins to be reported and represent a previously undescribed carbon skeleton. Plausible biosynthetic pathways of 1-4 were proposed. Compounds 1 and 2 were cytotoxic and active against Gram-positive bacteria.

Amiaspochalasins A-H, Undescribed Aspochalasins with a C-21 Ester Carbonyl from Aspergillus micronesiensis.

Amiaspochalasins A-H (1-8), eight undescribed aspochalasins, and trichalasin D (9), a known analogue, were isolated from the solid culture of Aspergillus micronesiensis. Compounds 1-9 are aspochalasins with a C-21 ester carbonyl, and their structures were determined by spectroscopic data, X-ray crystallographic analyses, electronic circular dichroism calculations, and chemical methods. The CH3-25 in compound 1 is located at C-16 rather than C-14 in the previously reported aspochalasins, endowing 1 with an unexpected carbon skeleton. Compounds 2 and 3 are the first examples of aspochalasins with an unprecedented 5/6/6/8 tetracyclic ring system. Compounds 4 and 5 are diastereomers of aspochalasins I and J, respectively. Compounds 6 and 7 are the first aspochalasins featuring a long open-chain system, and their absolute configurations were discussed by comparing the NMR data of the hydrolysis and methyl esterification products of 4 and 5. Compound 8 is an isomeride of 9. The cytotoxic and antimicrobial effects of 1-9 were tested.

Amichalasines A-C: Three Cytochalasan Heterotrimers from Aspergillus micronesiensis PG-1.

Amichalasines A-C (1-3), which represent a new type of cytochalasan heterotrimers, were isolated from Aspergillus micronesiensis PG-1. Compounds 1 and 2 possess an undecacyclic 5/6/11/5/5/6/6/5/11/6/5 ring system, and 3 has an additional furan ring with a dodecacyclic 5/6/11/5/5/6/6/5/5/11/6/5 ring system. 1 and 2 exhibited potent cytotoxic activities through apoptosis induction mediated by caspase-3 activation and PARP degradation, and their IC50 values against HL60 cells were 1.71 and 3.74 µM, respectively.

Dibrefeldins A and B, A pair of epimers representing the first brefeldin A dimers with cytotoxic activities from Penicillium janthinellum.

Dibrefeldins A and B (1 and 2), two unexpected brefeldin A (BFA) dimers, as well as brefeldin F (3), brefeldin G (4), and 14-hydroxy-BFA (5), three new BFA derivatives, together with three new naturally occurring BFA derivatives (6-8) and four known analogues (9-12), were isolated from the fungus Penicillium janthinellum. Dibrefeldins A and B (1 and 2) represent the first examples of BFA dimers formed by an esterification between two BFA monomer units. Brefeldin F (3) has an α,ß-unsaturated γ-lactone ring, and this moiety was first discovered in naturally occurring BFA derivatives. The structures and relative/absolute configurations of these derivatives were elucidated by extensive spectroscopic methods, 13C NMR calculations, and single-crystal X-ray diffraction. Compounds 1, 2, 8, and 9 showed excellent cytotoxic activities against six cancer cell lines with IC50 values ranging from 0.01 to 4.45 µM.

Brasilane sesquiterpenoids and dihydrobenzofuran derivatives from Aspergillus terreus [CFCC 81836].

Brasilanones A-F and asperterreusines A-C, undescribed brasilane sesquiterpenoids and dihydrobenzofuran derivatives, were isolated from the marine-derived fungus Aspergillus terreus [CFCC 81836]. Their structures with absolute configurations were elucidated on the basis of spectroscopic data, X-ray crystallographic analyses, and electronic circular dichroism (ECD) calculations. Brasilanones A-F are unusual brasilane sesquiterpenoids with an α,ß-unsaturated ketone unit, interestingly, brasilanones B-D are stereo isomers. All of the isolates were evaluated for their inhibitory activities against NO production and cytotoxic activities against five human cancer cell lines (HL-60, SW-480, A-549, MCF-7, and SMMC-7721). Brasilanones A and E showed moderate inhibitory effect with NO inhibition rates of 47.7% (p < 0.001) and 37.3% (p < 0.001) at the concentration of 40 µM. Asperterreusines A showed cytotoxicity against HL-60 and SW-480 cell lines with IC50 values of 15.3 and 25.7 µM, respectively.

Phenylacetylene-bearing 3,4-seco-cleistanthane diterpenoids from the roots of Phyllanthus glaucus.

Three new cleistanthane diterpenoids, phyllanglins A-C (1-3), a new natural product, 4-acetyl-bergenin (4), and three known compounds (5-7) were isolated from the roots of Phyllanthus glaucus. Their structures were elucidated by extensive spectroscopic data analyses and single-crystal X-ray diffraction. Phyllanglins A-C were unusual cleistanthane diterpenoids with phenylacetylene moieties, and a plausible biogenetic pathway was proposed to discuss the origins of them. All of the isolates were evaluated for their anti-inflammatory activities.

(±)-Terreinlactone A, a Pair of 3-Substituted δ-Lactone Enantiomers Derived from Terrein from the Fungus Aspergillus terreus.

Terreinlactone A (1a/1b), a pair of 3-substituted δ-lactone enantiomers, and terreinlactone B (2), a new biosynthetic intermediate of 1a/1b, were isolated from Aspergillus terreus, along with their biosynthetic precursor (+)-terrein (3) and (+)-isoterrein (4). Compounds 1a and 1b were separated by using a Daicel chiral-pak ASH column eluting with n-hexane-EtOH (80 : 20). The structures of 1a/1b with absolute configurations were determined by comprehensive spectroscopic analyses and electronic circular dichroic (ECD) calculations. Terreinlactone A (1) represents the first example of 1,5-seco-terrein and a biogenetic pathway is proposed from the precursor terrein via the intermediated terreinlactone B (2).

Atrichodermones A-C, three new secondary metabolites from the solid culture of an endophytic fungal strain, Trichoderma atroviride.

An endophytic fungal strain named Trichoderma atroviride was isolated from the bulb of Lycoris radiata. Following cultivation on rice medium, a novel 3-amino-5-hydroxy-5-vinyl-2-cyclopenten-1-one dimer, atrichodermone A (1), a new cyclopentenone derivative, atrichodermone B (2), and a new sesquiterpene, atrichodermone C (3), together with three known cyclopentenone derivatives (4-6) were isolated. Their structures were elucidated by extensive spectroscopic (UV, IR, ECD, HRESIMS, and NMR) data analyses, and absolute configurations of the new compounds were determined by comparing their experimental ECD spectra with structurally similar compounds and computational analyses of their electronic circular dichroism (ECD) spectra. Compounds 1-3 were evaluated for their cytotoxicity against HL60 and U937 cell lines, as well as anti-inflammatory effect against the production of the pro-inflammatory cytokines TNF-α and IL-1ß.

Aspergilasines A-D: Four Merocytochalasans with New Carbon Skeletons from Aspergillus flavipes QCS12.

Aspergilasines A-D (1-4), four merocytochalasans with new skeletons, were isolated from the liquid culture broth of Aspergillus flavipes QCS12. Aspergilasine A (1) possesses a uniquely caged pentacyclo[7.2.0.14,11.02,7.05,10]dodecane skeleton with an unexpected cyclobutane ring that formed by the fusion of two epicoccine moieties via two [3 + 2] cycloadditions. Aspergilasines B-D (2-4) are key biosynthetic intermediates of epicochalasine B that fit well with our previous biosynthetic proposal.

6,8-Di-C-methyl-flavonoids with neuroprotective activities from Rhododendron fortunei.

Six 6,8-di-C-methyl-flavonoids, (2R,3R)-6,8-di-C-methyl-5,7,4'-trihydroxyflavanonol 7-O-ß-d-gluco-pyranoside (1), (2R,3R)-6,8-di-C-methyl-5,7,4'-trihydroxyflavanonol 7-O-ß-d-xylopyranosyl(1→6)-ß-d-glucopyranoside (2), 6,8-di-C-methylkaempferol 7-O-ß-d-glucopyranoside (3), (2R)-farrerol (4a), (2R/2S)-farrerol 7-O-ß-d-glucopyranoside (5), and (2R/2S)-farrerol 7-O-ß-d-xylopyranosyl(1→6)-ß-d-glucopyranoside (6), and four known analogues, farrerol (4b), (2R,3R)-6,8-di-C-methyldihydrokae-mpferol (7), 6,8-di-C-methylkaempferol 7-O-ß-d-glucopyranoside (8), and 6,8-di-C-methylkaempferol (9), were isolated from the twigs and leaves of Rhododendron fortunei. The structures of compounds 1-9 were determined by spectroscopic analyses (HRESIMS, 1D and 2D NMR, and CD) and chemical methods. Compounds 1-9 were evaluated for their neuroprotective effects on the human neuroblastoma SH-SY5Y cells apoptosis induced by hydrogen peroxide (H2O2) and amyloid ß peptide (Aß), respectively. Compounds 1-3 and 5-9 exhibited significant neuroprotective effects against H2O2-induced SH-SY5Y cell apoptosis, and compound 8 exhibited the strongest activity with a improvement of cell viability by about 30% at the concentration of 10µM. Compounds 1-9 showed significant neuroprotective effects against Aß-induced SH-SY5Y cell apoptosis.

Enantiomeric Lignans and Neolignans from Phyllanthus glaucus: Enantioseparation and Their Absolute Configurations.

Eight pairs of enantiomeric neolignans, norlignans, and sesquineolignans (1a/1b-8a/8b), together with five known neolignans (9a/9b and 10-12), have been isolated from 70% acetone extract of the whole plants of Phyllanthus glaucus Wall. (Euphorbiaceae). The racemic or partial racemic mixtures were successfully separated by chiral HPLC using different types of chiral columns with various mobile phases. Their structures were elucidated on the basis of extensive spectroscopic data. The absolute configurations of 2a/2b were determined by computational analysis of their electronic circular dichroism (ECD) spectrum, and the absolute configurations of other isolates were ascertained by comparing their experimental ECD spectra and optical rotation values with those of structure-relevant compounds reported in literatures. Compounds 4a/4b featured unique sesquineolignan skeletons with a novel 7-4'-epoxy-8'-8''/7'-2'' scaffold, consisting of an aryltetrahydronaphthalene and a dihydrobenzofuran moiety. The planar structures of compounds 2, 3, 7, and 8 were documented previously; however, their absolute configurations were established for the first time in this study. The antioxidant activities of 1a/1b-8a/8b were evaluated using DPPH free radical scavenging assay, and the results demonstrated that compounds 1b and 3b showed potent DPPH radical scavenging activities with IC50 values of 5.987 ± 1.212 and 9.641 ± 0.865 µg/mL, respectively.

Neolignans with a Rare 2-Oxaspiro[4.5]deca-6,9-dien-8-one Motif from the Stem Bark of Cinnamomum subavenium.

Two pairs of racemic spirodienone neolignans with a rare 2-oxaspiro[4.5]deca-6,9-dien-8-one motif, named (±)-subaveniumins A (1) and B (2), were isolated from the bark of Cinnamomum subavenium. The chiral separation of the (+)-1, (-)-1, (+)-2, and (-)-2 enantiomers was accomplished via high-performance liquid chromatography on a chiral column. Their structures were elucidated using single-crystal X-ray diffraction and spectroscopic analyses (UV, IR, HRESIMS, and 1D and 2D NMR). The absolute configurations of the enantiomers were determined by comparing the experimental and calculated electronic circular dichroic spectra. The (+)-1, (-)-1, (+)-2, and (-)-2 enantiomers exhibited moderate inhibitory effects against NO production in RAW264.7 mouse macrophages induced by lipopolysaccharide, with IC50 values of 17.9, 5.6, 15.1, and 4.3 µM, respectively.