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Camellia taliensis (W. W. Smith) Melchior, belonging to the genus Camellia sect. Thea., is mainly distributed from northern Myanmar to western and southwestern Yunnan province of China, and its leaves have been used to make various teas by the locals of its growing regions. The chemical constituents of C. taliensis are significantly related to those of cultivated tea plants, C. sinensis and C. sinensis var. assamica. The HPLC-ESI-MS analysis of black tea prepared from the leaves of C. taliensis showed a rich existence of polyphenols. Further comprehensive chemical study led to the separation and recognition of 32 compounds (1–32), including one new hydrolyzable tannin, 1-O-galloyl-4,6-tetrahydroxydibenzofurandicarboxyl-β-D-glucopyranose (1), and one new natural product (24). The known compounds referred to seven hydrolyzable tannins (2–8), 10 flavonols and glycosides (9–18), and 14 simple phenolics (19–32). Their structures were elucidated by comprehensive spectroscopic analyses. Among them, 20 compounds (2, 3, 6, 7, 8, 15, 17, 18, 20–22, 24–32) were isolated from black tea for the first time. Most isolates displayed obvious antioxidant activities on DPPH and ABTS+ assays, and the hydrolyzable tannins 1, 3–5, 7, and 8 exhibited stronger inhibitory activities on α-glycosidase than quercetin and acarbose (IC50 = 5.75 and 223.30 μM, respectively), with IC50 values ranging from 0.67 to 2.01 μM. [ABSTRACT FROM AUTHOR]

Eleven flavonoids including one new flavonol glycoside, quercetin-3-O-(2-α-L-rhamnopyranosyl)-β-D-glucuronopyranosyl methyl ester (1), were isolated for the first time from the fruits of Phyllanthus acidus (L.) Skeels (Phyllanthaceae). Their structures were determined by extensive spectroscopic data. The known flavonoids, quercetin-3-O-β-D-glucuronide methyl ester (3), quercetin-3-O-(2''-α-L-rhamnopyranosyl-6''-O-α-L-rhamno pyranosyl)-β-D-glucopyranoside (5), myricetin (9), and 6-methoxy-naringenin (11) were isolated for the first time from the genus Phyllanthus. Flavonoids 4, 6 and 9 (IC50 = 6.01, 6.32, and 7.84 μM, respectively) showed stronger α-glucosidase inhibitory activities than the positive control, acarbose (IC50 = 306.45 μM). The fruits of P. acidus might be further developed as an anti-diabetic food supplement. [ABSTRACT FROM AUTHOR]

The separable nonlinear least-squares (SNLLS) problems considered in this article frequently appear in a wide range of research fields, such as machine learning, computer vision, system identification, and signal processing. The variable projection algorithm proposed by Golub and Pereyra, which reduces the dimension of the parameters by projecting the linear parameters out of the problem, is quite valuable in solving SNLLS problems. Previous implementations of the variable projection algorithm are based on matrix factorization. In this article, we propose an iterative implementation of the variable projection algorithm. Compared with previous implementations based on matrix decomposition, the proposed method can effectively avoid suffering from large condition number of the matrix or even matrix decomposition failure when dealing with ill-posed SNLLS problems. Numerical experiments on real-world data and synthetic data show the efficiency and robustness of the proposed iterative variable projection algorithm. [ABSTRACT FROM AUTHOR]

Phyllaciduloids E (1) and F (2), two new cleistanthane diterpenoids, were isolated from the leaves of Phyllanthus acidus (L.) Skeels (Phyllanthaceae). Their planar structures were established by spectroscopic analysis and comparison with literature values. The relative configurations of phyllaciduloids E and F were confirmed by DFT-NMR chemical shift calculations and subsequent CP3 probability methods. Phyllaciduloids E and F were evaluated for their cytotoxicity. However, no significant activities were detected at concentrations up to 40 μM. [ABSTRACT FROM AUTHOR]

The broad learning system (BLS) is an emerging flat network, which has demonstrated its outstanding performance in classification and regression problems. The regularization plays an important role in the performance of the BLS. In real applications, since the BLS network is usually expanded dynamically, a predetermined regularization parameter may reduce the performance of the network. Using a fixed regularization in some cases, the classification accuracy of the BLS decreases dramatically when we expand the network. To alleviate this problem, we propose a method that automatically finds appropriate regularization parameters for different datasets, which is based on the weighted generalized cross-validation (WGCV). The experimental results indicate that the WGCV method improves the performance of the BLS, and alleviates the accuracy decrease of the incremental learning algorithm. [ABSTRACT FROM AUTHOR]

A novel highly oxygenated norbisabolane sesquiterpene, namely phyllanthacidoid U (1), along with nine known sesquiterpenes (2–10) was isolated from the roots and stems of Phyllanthus acidus (L.) Skeels (Phyllanthaceae), collected from Xishuangbanna, Yunnan province, China. Their structures were elucidated by means of extensive spectroscopic analysis and by comparison of their data with reported values in literatures. Instead of the C-13 ester O-glycosyl found mostly in the titled plant growing in Thailand, compound 1 possessed a rare N-β-glucosamine-2-N-acetate moiety linked directly to the carbonyl at C-13 through an amido bond. Moreover, the acyl group at C-10 in 1 was (Z)-2-(2-hydroxyethyl)-pent-2-enedioyl group, instead of benzoic or p-hydroxybenzoic moieties found commonly in the reported norbisabolane sesquiterpenes. The known sesquiterpene 5 displayed stronger anti hepatitis B virus (HBV) activity with IC50 values of 1.69 ± 0.22 and 2.79 ± 0.69 μM towards HBV surface antigen (HBsAg) and HBV excreted antigen (HBeAg) secretion, respectively. [ABSTRACT FROM AUTHOR]

The fresh leaves of Metapanax delavayi (Araliaceae) have been used as a common wild vegetable for salad and soup, and also herbal tea by the local people living in its growing areas of Yunnan province, China. Detailed chemical investigation led to the identification of a new triterpenoid saponin, 3-O-α-L-arabinopyranosyl-28-O-β-D-glucopyranosyl-(1→6)-O-β-D-glucopyranosyl-3β-hydroxyolean-12-ene-28,29-dioic acid (1) from the fresh leaves, together with 11 known compounds, including six triterpenoid saponins (2–7), two caffeoylquinic acid derivatives (8–9), and three flavonoid glycosides (10–12). Their structures were determined on the basis of spectroscopic analysis and acidic hydrolysis. Compounds 3–5 and 8–12 were isolated from M. delavayi for the first time. Moreover, the known saponins 3-O-β-D-xylopyranosyl-3β-hydroxyolean-12-ene-28,29-dioic acid (3) and yiyeliangwanoside IV (5) exhibited protective effects on HepG2 cells damaged by the alcohol intakes, at a concentration of 1.0 µg/mL. The results indicated M. delavayi is an ideal dietary vegetable and herbal tea with potential hepatoprotective activity. [ABSTRACT FROM AUTHOR]

Dasiphora fruticosa L. (Rosaceae), also known as Potentilla fruticosa L. (syn.), is a hardy deciduous shrub widely distributed in the north temperate regions of the world. Three methylene bisflavan-3-ols (1-3), together with a procyanidin dimer, (-)-afzelechin-(4α→8)-(-)-afzelechin (4) were isolated for the first time from the branches and leaves of the titled plant, in addition to 11 known compounds (5-15). Their structures were elucidated by means of extensive spectroscopic analysis and by comparison with data reported in the literatures. Methylene 6,8-bis(7-O-glucosyl) catechin (1) was determined to be a new dimeric flavan-3-ol glycoside through a methylene linkage between C-8 and C-8 of two units. At a concentration of 128 μg/mL, the known compounds 9 – 13 exhibited antibacterial activities on Escherichia coli, Staphylococcus aureus subsp. aureus, Salmonella enterica subsp. enterica, and Pseudomonas aeruginosa. Compound 12 also showed certain glucose uptake stimulating activity. [ABSTRACT FROM AUTHOR]

Objective To investigate the expression heterogeneity of transforming growth factor-β-induced protein (TGFBI) in glioblastoma (GBM) multiform and the mechanism of its promotion on malignancy of glioma stem cells (GSCs) in vitro. Methods Using The Cancer Genome Atlas (TCGA), Chinese Glioma Genome Atlas (CGGA), REMBRANDT and Oncomine database to analyse the potential associations between grades, subtypes, overall survival (OS) of GBM and the expression level of TGFBI and the correlation between TGFBI and tumor-associated macrophages (TAMs) marker CD11b and CD163. Treating human monocytes cell line U937 with sequential peripheral blood mononuclear cells and IL-4 to get Primed- and M2-TAMs, quantitative real-time polymerase chain reaction (qRT-PCR) were used to detect the expression level of markers for M1 -, M2 - TAMs and TGFBI. Performing immunofluorescent and immunohistochemical stain to reveal the distribution of TGFBI, M2-TAMs and GSCs in specimen of GBM patients, adding rhTGFBI to the culture medium to see its impacts on the sphere formation and invasion capacity of NCH-421K. Results According to the RNA-seq and microarray data of GBM patients in each database, expression level of TGFBI positively correlated to GBM grades and negatively to OS, Furthermore, expression level of TGFBI were strongly correlate with either pan TAMs marker CD11b or M2-TAMs marker CD163, and as the induction of U937-derived M2-TAMs, the expression level of M2-TAMs marker and TGFBI increased accompanied by decreasingly M1-TAMs marker. Also, we found an obvious co-location between TGFBI and CD163, SOX2 in frozen and paraffin sections of GBM specimens. Lastly, we demonstrate that rhTGF86BI could enhance the sphere formation and invasion capacity of NCH-421K in vitro. Conclusions M2-TAMs secrete TGFBI to promote the sphere formation and invasion capacity of GSCs in GBM. [ABSTRACT FROM AUTHOR]

• Complicated gallstone disease during pregnancy can be successfully managed by combined laparoscopic cholecystectomy and exploration of common bile duct through trans-cystic duct approach. • This approach is safe and can cure cholecystitis and choledocholithiasis in one goal. • This approach avoids ionizing radiation to the developing fetus. Choledocholithiasis during pregnancy is relatively uncommon but it can be life-threatening. Therapeutic endoscopic retrograde cholangiopancreatography (ERCP) poses the risk of ionizing radiation exposure to the developing fetus. Other strategies are thus needed to tackle this problem. A 38-year-old 8 weeks' pregnant lady presented with acute onset of right upper quadrant pain. Ultrasonography showed features of acute cholecystitis and choledocholithiasis, which was later confirmed by magnetic resonance cholangiogram. Emergency combined laparoscopic cholecystectomy (LC) and laparoscopic exploration of common bile duct (Lap ECBD) were performed. Lap ECBD through trans-cystic duct approach was adopted. The patient recovered uneventfully and was discharged on postoperative day 4. A healthy baby boy was delivered at 40 weeks' gestation without developmental problem. Lap ECBD avoided ionizing radiation for choledocholithiasis during pregnancy, and can combined with LC as an effective minimally invasive procedure for complicated gallstone disease. [ABSTRACT FROM AUTHOR]

Two new sphingofungins G (1) and H (2) with a five-membered lactone ring were identified from the solid-state fermentation of Aspergillus penicilliodes Speg., a dominant microorganism isolated previously from the post-fermentation of ripe Pu-er tea, together with six known metabolites. Their structures were elucidated by extensive spectroscopic methods. All of them were isolated from the mycelia culture of A. penicilliodes for the first time. The known compound, trypacidin, exhibited potent cytotoxities against five human cancer cell lines, e.g. myeloid leukemia HL-60, lung cancer A-549, hepatocellular carcinoma SMMC7721, breast cancer MCF-7, and colon cancer SW480, with IC50 values of 0.55, 11.45, 10.95, 3.58, and 3.49 μM, resp., while cisplatin as the positive control, with IC50 values of 8.63, 24.15, 21.99, 27.29, and 23.61 μM, resp. [ABSTRACT FROM AUTHOR]

Abstract Arsenic (As) can be easily enriched in atmospheric particulate matters (PMs), especially in fine particulate matters (PM 2.5). In this study, thirty two PM 2.5 samples were collected in four seasons in Baoding, China, where the haze pollution was very serious in recent years. The total contents, species and bioavailability of arsenic in PM 2.5 samples were investigated. Species of arsenic in the PM 2.5 samples were discriminated as five fractions using a sequential extraction method: non-specifically sorbed fraction (F1), specifically-sorbed fraction (F2), amorphous and poorly-crystalline hydrous oxides of Fe and Al fraction (F3), well-crystallized hydrous oxides of Fe and Al fraction (F4) and residual fraction (F5). Bioavailabilities of arsenic in the PM 2.5 samples were evaluated by in vitro tests using both solubility bioavailability research consortium (SBRC) and Gamble's solution extraction methods. The total volume concentrations of As in PM 2.5 were significantly higher in winter than the other seasons. However, the highest mass concentration of As was found in spring. Scanning electron microscopy (SEM) characterization indicated that the physical morphology of the particles varied in different seasons. Significant differences of fraction distribution and BFs were found between different seasons. Arsenic in PM 2.5 samples mainly presented in F1 with high bioavailability factor (BF), especially for the samples in summer. In vitro tests indicated that arsenic in PM 2.5 could be dissolved more easily in gastric phase rather than intestinal and lung phases. There was a significant correlation between species and in vitro tests. Interestingly, a synergy effect was found between F2 and F3. Health risk assessment indicated that arsenic in PM 2.5 via inhalation exposure for both children and adults could cause adverse effects. Principal component analysis suggested that the arsenic in PM 2.5 was from the similar sources between summer and autumn, winter and spring, respectively. Highlights • High concentration of As was found in PM 2.5 samples in Baoding city. • The species and bioavailability of As and their seasonal variation were investigated. • Health risks and correlations between diffent species were evaluated and discussed. [ABSTRACT FROM AUTHOR]

Further phytochemical investigation of the steaming treated roots of Panax notoginseng (Araliaceae) led to the identification of two new dammarane-type triterpenoid saponins, notoginsenoside SP20 (1) and SP21 (2). In addition, a pair of new phenolic glycosides (3a and 3b) was also isolated together with two known compounds. Their structures were elucidated by HRESIMS, 1D- and 2D-NMR spectra. Compounds 1 and 2 showed no in vitro cytotoxicity against five human cancer cell lines (HL-60, SMMC-7712, A-549, MCF-9 and SW480). [ABSTRACT FROM AUTHOR]

Fifty-eight phenolic compounds isolated from Phyllanthus emblica were screened and compared for their in vitro and in vivo antioxidant properties, as well as hyaluronidase (HAase) inhibitory activities. Among them, 20 compounds showed to be promising antioxidants due to the stronger scavenging activity in both DPPH radical and Danio rerio reactive oxygen species assays, while nine compounds were potential HAase inhibitors with 100-fold stronger activities than that of the positive control, DSCG. The structure activity relationship was discussed. [ABSTRACT FROM AUTHOR]