The effect of flow partition on storm runoff and pollutant retention through raingardens with and without subsurface drainage.

Green infrastructures (GIs) have been advocated worldwide to mitigate the negative impact of urbanization on regional hydrological cycle, their functions are closely related to their design features and the local environmental condition. This paper reports a field monitoring study that aimed to investigate how runoff partition in raingardens would affect flow and pollutant retention. A paired field experiment was conducted to compare runoff and pollutant retentions in two raingardens with and without subsurface drainage in a shallow water table area. Concentrations of ammonia nitrogen (NH3-N), nitrate nitrogen (NO3-N) and total phosphorus (TP) were measured at raingarden inflow, overflow and drainage paths. The results from 28 monitored storm events over two years showed that the raingarden without subsurface drainage achieved its retention mainly through ponding and infiltration, its pollutant retention rates (76% for TP, 81% for NO3-N, and 79% for NH3-N) were higher than its runoff retention rate (61%), indicating a first flush effect on pollutants retention in the raingarden during storm events, especially when the raingarden was empty and dry. The raingarden with subsurface drainage facilitated quick discharge of water, the observed runoff reduction through the raingarden was 36%; pollutant removal rates were quite variable: NH3-N was removed by 91% while the NO3-N and TP were increased by 3-47%. These results suggest that facilitating specific processes for targeted pollutants is necessary for achieving substantial pollutant removal in a stormwater retention device. Subsurface drainage pipes resulted in short circulating of runoff and lowered pollutant removal rates in the raingarden. Considering the water table fluctuation during the experimental period, we recommend to build infiltration-based GI devices to better capture first flush in intensively developed urban area, which caused deeper groundwater table. In conclusion, installations of different GI devices in urban landscape need to consider the local environmental conditions and facilitate the design features to meet specific storm runoff and pollutants mitigation requirement.

Prevalence and intervention of preoperative anemia in Chinese adults: A retrospective cross-sectional study based on national preoperative anemia database.

BACKGROUND: Preoperative anemia is an important pillar of perioperative patient blood management. However, there was no literature comprehensively described the current situation of preoperative anemia in China. METHODS: We conducted a national retrospective cross-sectional study to assess the prevalence and intervention of preoperative anemia in Chinese adults. Data were from the National Preoperative Anemia Database based on hospital administration data from January 1, 2013 to December 31, 2018. FINDINGS: A total of 797,002 patients were included for analysis. Overall, 27.57% (95% CI 27.47-27.67) of patients had preoperative anemia, which varied by gender, age, regions, and type of operation. Patients who were female, age over 60 years old, from South China, from provinces with lower per capita GDP, underwent operations on the lymphatic and hematopoietic system, with laboratory abnormalities were more likely to have a high risk of preoperative anemia. Among patients with preoperative anemia, 5.16% (95% CI 5.07-5.26) received red blood cell transfusion, 7.79% (95% CI 7.67-7.91) received anemia-related medications such as iron, erythropoietin, folic acid or vitamin B12, and 12.25% (95% CI 12.10-12.40) received anemia-related therapy (red blood cell transfusion or anemia-related medications) before operation. The probability of preoperative RBC transfusion decreased by 54.92% (OR 0.46, 95% CI 0.46-0.47) as each 10-g/L increase in preoperative hemoglobin. Patients with preoperative hemoglobin less than 130 g/L was associated with longer hospital stay and more hospital costs. Patients with severe preoperative anemia given iron preoperatively had lower intra/post-operative RBC transfusion rate, shorter length of stay and less hospitalization costs, but no similar correlation was found in patients with mild and moderate preoperative anemia and patients given erythropoietin preoperatively. INTERPRETATION: Our present study shows that preoperative anemia is currently a relatively prevalent problem that has not been fully appreciated in China. More researches will be required to optimize the treatment of preoperative anemia. FUNDING: National Natural Science Foundation of China and the Logistics Support Department of the Central Military Commission.

In vitro evaluation of potential bitterness-masking terpenoids from the Canada goldenrod (Solidago canadensis).

In a screening of extracts of selected plants native to Ohio against the human bitterness receptor hTAS2R31, a chloroform-soluble extract of the aerial parts of Solidago canadensis (Canada goldenrod) was determined to have hTAS2R31 antagonistic activity and, thus, was fractionated for isolation of potential bitterness-masking agents. One new labdane diterpenoid, solidagol (1), and six known terpenoids, including two labdane diterpenoids (2 and 3), three clerodane diterpenoids (6ß-angeloyloxykolavenic acid, 6ß-tigloyloxykolavenic acid, and crotonic acid), and a triterpenoid (longispinogenin), were isolated. Among these compounds, 3ß-acetoxycopalic acid (2) was found to be the first member of the labdane diterpene class shown to have inhibitory activity against hTAS2R31 activation (IC50 8 µM). A homology model of hTAS2R31 was constructed, and the molecular docking of 2 to this model indicated that this diterpenoid binds well to the active site of hTAS2R31, whereas this was not the case for the closely structurally related compound 3 (sempervirenic acid). The content of 2 in the chloroform-soluble portion of the methanolic extract of S. canadensis was up to 2.24 g/100 g dry weight, as determined by HPLC.

In vitro evaluation of flavonoids from Eriodictyon californicum for antagonist activity against the bitterness receptor hTAS2R31.

The leaves of the native North American plant, Eriodictyon californicum, were once used to mask the bitter taste of pharmaceuticals, an application currently of importance. Ten flavonoids (1-10) were isolated from the leaves of E. californicum, of which the structure and absolute configuration of 6-methoxyhesperetin (8) were assigned for the first time. In addition, the absolute configurations at C-2 were established for 4'-isobutyrylhomoeriodictyol (3) and 6-methoxyhomoeriodictyol (7). Using a cell-based assay, it was determined that the 7-methoxylated flavanones, sakuranetin (2) and 6-methoxysakuranetin (9), and the flavone, jaceosidin (10), are antagonists of hTAS2R31.

A minor, sweet cucurbitane glycoside from Siraitia grosvenorii.

A minor, sweet cucurbitane-glycoside, named iso-mogroside V (1), was isolated from Luo Han Guo (Siraitia grosvenorii (Swingle) C. Jeffery) along with five previously reported mogrosides. The structure of iso-mogroside V, 3-[(4-O-beta-D-glucopyranosyl-beta-D-glucopyranosyl)oxy]-mogrol-24-O-beta-D-glucopyranosyl-(1-->2)-O-[beta-D-glucopyranosyl-(1-->6)]beta-D-glucopyranoside, was established on the basis of extensive 2D-NMR (COSY, TOCSY, NOESY, HSQC, and HMBC) and LCMS analyses. The five known mogrosides were identified as mogroside V (2), 11-oxo-mogroside V (3), siamenoside I (4), mogrosides IVa (5) and IVe (6). Iso-mogroside V was determined to be approximately 500 times sweeter than 0.5% (w/v) sucrose.

Biologically active triterpenoid saponins from Ardisia japonica.

Eleven new triterpenoid saponins, ardisianosides A (1), B (2), C (4), D (5), E (6), F (7), G (15), H (16), I (17), J (18), and K (19), together with 10 known saponins, were isolated from the whole plants of Ardisia japonica. The structures of the new saponins were established on the basis of extensive 1D and 2D NMR and MS studies coupled with chemical degradations. The cytotoxic activities of saponins 1-21 are reported against three human cancer cell lines, namely, HL-60 myeloid leukemia, KATO-III stomach adenocarcinoma, and A549 lung adenocarcinoma cells.

Structural analysis of xyloglucans in the primary cell walls of plants in the subclass Asteridae.

The structures of xyloglucans from several plants in the subclass Asteridae were examined to determine how their structures vary in different taxonomic orders. Xyloglucans, solubilized from plant cell walls by a sequential (enzymatic and chemical) extraction procedure, were isolated, and their structures were characterized by NMR spectroscopy and mass spectrometry. All campanulids examined, including Lactuca sativa (lettuce, order Asterales), Tenacetum ptarmiciflorum (dusty miller, order Asterales), and Daucus carota (carrot, order Apiales), produce typical xyloglucans that have an XXXG-type branching pattern and contain alpha-d-Xylp-, beta-D-Galp-(1-->2)-alpha-D-Xylp-, and alpha-L-Fucp-(1-->2)-beta-D-Galp-(1-->2)-alpha-D-Xylp- side chains. However, the lamiids produce atypical xyloglucans. For example, previous analyses showed that Capsicum annum (pepper) and Lycopersicon esculentum (tomato), two species in the order Solanales, and Olea europaea (olive, order Lamiales) produce xyloglucans that contain arabinosyl and galactosyl residues, but lack fucosyl residues. The XXGG-type xyloglucans produced by Solanaceous species are less branched than the XXXG-type xyloglucan produced by Olea europaea. This study shows that Ipomoea pupurea (morning glory, order Solanales), Ocimum basilicum (basil, order Lamiales), and Plantago major (plantain, order Lamiales) all produce xyloglucans that lack fucosyl residues and have an unusual XXGGG-type branching pattern in which the basic repeating core contains five glucose subunits in the backbone. Furthermore, Neruim oleander (order Gentianales) produces an XXXG-type xyloglucan that contains arabinosyl, galactosyl, and fucosyl residues. The appearance of this intermediate xyloglucan structure in oleander has implications regarding the evolutionary development of xyloglucan structure and its role in primary plant cell walls.

NMR characterization of endogenously O-acetylated oligosaccharides isolated from tomato (Lycopersicon esculentum) xyloglucan.

Eight oligosaccharide subunits, generated by endoglucanase treatment of the plant polysaccharide xyloglucan isolated from the culture filtrate of suspension-cultured tomato (Lycopersicon esculentum) cells, were structurally characterized by NMR spectroscopy. These oligosaccharides, which contain up to three endogenous O-acetyl substituents, consist of a cellotetraose core with alpha-D-Xylp residues at O-6 of the two beta-D-Glcp residues at the non-reducing end of the core. Some of the alpha-D-Xylp residues themselves bear either an alpha-L-Arap or a beta-D-Galp residue at O-2. O-Acetyl substituents are located at O-6 of the unbranched (internal) beta-D-Glcp residue, O-6 of the terminal beta-D-Galp residue, and/or at O-5 of the terminal alpha-L-Arap residue. Structural assignments were facilitated by long-range scalar coupling interactions observed in the high-resolution gCOSY spectra of the oligosaccharides. The presence of five-bond scalar coupling constants in the gCOSY spectra provides a direct method of assigning O-acetylation sites, which may prove generally useful in the analysis of O-acylated glycans. Spectral assignment of these endogenously O-acetylated oligosaccharides makes it possible to deduce correlations between their structural features and the chemical shifts of diagnostic resonances in their NMR spectra.

Analysis of xyloglucan fucosylation in Arabidopsis.

Xyloglucan (XyG) is a load-bearing primary wall component in dicotyledonous and non-graminaceous monocotyledonous plants. XyG fucosyltransferase (FUTase), encoded by the Arabidopsis gene AtFUT1, directs addition of fucose (Fuc) residues to terminal galactose residues on XyG side chains. Reverse transcription-polymerase chain reaction and analysis of promoter-beta-glucuronidase transgenic plants indicated highest expression of AtFUT1 in the upper portion of elongating inflorescence stems of Arabidopsis. XyG FUTase activity was highest in Golgi vesicles prepared from growing Arabidopsis tissues and low in those isolated from mature tissues. There was no discernible correlation between the Fuc contents of XyG oligosaccharides derived from different Arabidopsis organs and the level of AtFUT1 expression in the organs. Thus, organ-specific variations in AtFUT1 expression and enzyme activity probably reflect differential rates of cell wall biosynthesis, rather than differences in levels of XyG fucosylation. The effects of manipulating AtFUT1 expression were examined using an Arabidopsis mutant (atfut1) containing a T-DNA insertion in the AtFUT1 locus and transgenic plants with strong constitutive expression of AtFUT1. No Fuc was detected in XyG derived from leaves or roots of atfut1. Plants overexpressing AtFUT1 had higher XyG FUTase activity than wild-type plants, but the XyG oligosaccharides derived from the transgenic and wild-type plants contained comparable amounts of Fuc, indicating that suitable acceptor substrates are limiting. Galactosyl residues had slightly higher levels of O-acetylation in XyG from plants that overexpressed AtFUT1 than in XyG from wild-type plants. O-Acetylation of galactose residues was considerably reduced in Fuc-deficient mutants (atfut1, mur1, and mur2) that synthesize XyG containing little or no Fuc. These results suggest that fucosylated XyG is a suitable substrate for at least one O-acetyltransferase in Arabidopsis.

Structure of the xyloglucan produced by suspension-cultured tomato cells.

The xyloglucan secreted by suspension-cultured tomato (Lycopersicon esculentum) cells was structurally characterized by analysis of the oligosaccharides generated by treating the polysaccharide with a xyloglucan-specific endoglucanase (XEG). These oligosaccharide subunits were chemically reduced to form the corresponding oligoglycosyl alditols, which were isolated by high-performance liquid chromatography (HPLC). Thirteen of the oligoglycosyl alditols were structurally characterized by a combination of matrix-assisted laser-desorption ionization mass spectrometry and two-dimensional nuclear magnetic resonance (NMR) spectroscopy. Nine of the oligoglycosyl alditols (GXGGol, XXGGol, GSGGol, XSGGol, LXGGol, XTGGol, LSGGol, LLGGol, and LTGGol, [see, Fry, S.C.; York, W.S., et al., Physiologia Plantarum 1993, 89, 1-3, for this nomenclature]) are derived from oligosaccharide subunits that have a cellotetraose backbone. Very small amounts of oligoglycosyl alditols (XGGol, XGGXXGGol, XXGGXGGol, and XGGXSGGol) derived from oligosaccharide subunits that have a cellotriose or celloheptaose backbone were also purified and characterized. The results demonstrate that the xyloglucan secreted by suspension-cultured tomato cells is very complex and is composed predominantly of 'XXGG-type' subunits with a cellotetraose backbone. The rigorous characterization of the oligoglycosyl alditols and assignment of their 1H and 13C NMR spectra constitute a robust data set that can be used as the basis for rapid and accurate structural profiling of xyloglucans produced by Solanaceous plant species and the characterization of enzymes involved in the synthesis, modification, and breakdown of these polysaccharides.

Active site mapping and substrate channeling in the sterol methyltransferase pathway.

Sterol methyltransferase (SMT) from Saccharomyces cerevisiae was purified from Escherichia coli BL21(DE3) and labeled with the mechanism-based irreversible inhibitor [3-3H]26,27-dehydrozymosterol (26,27-DHZ). A 5-kDa tryptic digest peptide fragment containing six acidic residues at positions Glu-64, Asp-65, Glu-68, Asp-79, Glu-82, and Glu-98 was determined to contain the substrate analog covalently attached to Glu-68 by Edman sequencing and radioanalysis using C18 reverse phase high performance liquid chromatography. Site-directed mutagenesis of the six acidic residues to leucine followed by activity assay of the purified mutants confirmed Glu-68 as the only residue to participate in affinity labeling. Equilibration studies indicated that zymosterol and 26,27-DHZ were bound to native and the E68L mutant with similar affinity, whereas S-adenosylmethionine was bound only to the native SMT, K(d) of about 2 microm. Analysis of the incubation products of the wild-type and six leucine mutants by GC-MS demonstrated that zymosterol was converted to fecosterol, 26,27-DHZ was converted to 26-homo-cholesta-8(9),23(24)E,26(26')-trienol as well as 26-homocholesta-8(9),26(26')-3beta,24beta-dienol, and in the case of D79L and E82L mutants, zymosterol was also converted to a new product, 24-methylzymosta-8,25(27)-dienol. The structures of the methylenecyclopropane ring-opened olefins were determined unambiguously by a combination of (1)H and (13)C NMR techniques. A K(m) of 15 microm, K(cat) of 8 x 10(-4) s(-1), and partition ratio of 0.03 was established for 26,27-DHZ, suggesting that the methylenecyclopropane can serve as a lead structure for a new class of antifungal agents. Taken together, partitioning that leads to loss of enzyme function is the result of 26,27-DHZ catalysis forming a highly reactive cationic intermediate that interacts with the enzyme in a region normally not occupied by the zymosterol high energy intermediate as a consequence of less than perfect control. Alternatively, the gain in enzyme function resulting from the production of a delta(25(27))-olefin originates with the leucine substitution directing substrate channeling along different reaction channels in a similar region at the active site.

Purification, characterization and catalytic properties of human sterol 8-isomerase.

CHO 2, encoding human sterol 8-isomerase (hSI), was introduced into plasmids pYX213 or pET23a. The resulting native protein was overexpressed in erg 2 yeast cells and purified to apparent homogeneity. The enzyme exhibited a K (m) of 50 microM and a turnover number of 0.423 s(-1) for zymosterol, an isoelectric point of 7.70, a native molecular mass of 107000 Da and was tetrameric. The structural features of zymosterol provided optimal substrate acceptability. Biomimetic studies of acid-catalysed isomerization of zymosterol resulted in formation of cholest-8(14)-enol, whereas the enzyme-generated product was a Delta(7)-sterol, suggesting absolute stereochemical control of the reaction by hSI. Using (2)H(2)O and either zymosterol or cholesta-7,24-dienol as substrates, the reversibility of the reaction was confirmed by GC-MS of the deuterated products. The positional specific incorporation of deuterium at C-9alpha was established by a combination of (1)H- and (13)C-NMR analyses of the enzyme-generated cholesta-7,24-dienol. Kinetic analyses indicated the reaction equilibrium ( K (eq)=14; DeltaG(o')=-6.5 kJ/mol) for double-bond isomerization favoured the forward direction, Delta(8) to Delta(7). Treatment of hSI with different high-energy intermediate analogues produced the following dissociation constants ( K (i)): emopamil (2 microM)=tamoxifen (1 microM)=tridemorph (1 microM)<25-azacholesterol (21 microM)