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Two new guaiane-type sesquiterpenes, wenyujinolides A ( 1 ) and B ( 2 ), were isolated from the ethanol extract of Curcuma wenyujin , together with 10 known compounds. Their structures were established by extensive spectroscopic methods (IR, ESIMS, HRESIMS, ECD, 1D and 2D NMR) and comparison of their NMR data with literatures. Compounds 1 and 2 were evaluated for the inhibition of NO production in LPS induced RAW 264.7 macrophages.

Six new compounds, including two depsidones garciculendepsidones A and B (1 and 2), one prenylated xanthone garciculenxanthone (3) and three dimeric xanthones bigarciculenxanthones A-C (4-6), were isolated from the twigs and leaves of Garcinia esculenta Y. H. Li. Their structures were elucidated based on comprehensive analyses of spectral data, including HRESIMS, 1D and 2D NMR, and ECD calculation. All the isolates were tested for their cytotoxicity against five human cancer cell lines (myeloid leukemia HL-60, lung cancer A-549 cells, hepatocellular carcinoma SMMC-7721, breast cancer MDA-MB-231 and colon cancer SW480), among them, compounds 3-5 displayed cytotoxic potential, especially garciculenxanthone (3) had the lowest IC 50 value of 8.2 μm for lung cancer A-549 cells., Competing Interests: Declaration of Competing Interest The authors of the present manuscript have declared that no competing interests exist., (Copyright © 2023 Elsevier B.V. All rights reserved.)

To clarify the effect of pH on the structure and functional traits of soil microbial communities in purple soils, three purple upland soils developed from the same parent material that differed in pH were selected as the research objects, and metagenomic shotgun sequencing was used to investigate the structure and functional traits of the microbial communities among different pH soils. The shotgun sequencing identified a total of 89 phyla, 222 classes, 527 orders, 1009 families, 2769 genera, and 14354 species in these soils. Regardless of the phylogenetic classification level, the microbial community structures of these three purple soils with different pHs were significantly different. RDA results corroborated the highly significant difference in the microbial community structures among the three purple soils with different pHs, and the soil properties tested here all had significant correlations with soil microbial community structure, in which the soil pH had the greatest effect ( R 2 =0.9985, P =0.001). However, the results of investigating the microbial community functions revealed that the main metabolic processes of the three purple soils were all involved in unknown functions, global and overview maps, amino acid metabolism, carbohydrate metabolism, ammonia assimilation, etc. There was almost no significant difference in the relative abundance of microbes in the three purple soils annotated with the same function regardless of the COG/KEGG functional database and nitrogen cycling functional database, indicating that the overall function trait of soil microbial community was relatively conservative and not easily affected by environmental factors.

Soil pH is recognized as an important environmental factor in determining the niche differentiation for ammonia-oxidizing bacteria (AOB) and ammonia-oxidizing archaea (AOA) communities. Species of comammox, a single microorganism capable of the complete oxidation of ammonia to nitrate, have recently been discovered. Metagenomic analysis and quantitative PCR showed that Comammox Nitrospira were found in a wide range of environments, including soil. Comammox bacteria are differentiated into one of two clades (A and B) based on the phylogeny of genes encoding the α-subunit of ammonia monooxygenase genes ( amoA ). However, all discovered Comammox Nitrospira strains have been isolated and cultured in aquatic ecosystems, including N. inopinata, N. nitrosa, and N. nitrificans , all belonging to clade A. Currently, Comammox Nitrospira has not been obtained from soil environments, which limits our understanding of soil Comammox Nitrospira . Here we hypothesized that, as AOA and AOB, the ecological site of Comammox Nitrospira may also be affected by pH. Therefore, soil samples with differing pH were collected, and the abundances and community structures were studied to elucidate the mechanism of pH effect on the distributions and community compositions of Comammox Nitrospira in soil. Quantitative PCR of comammox clade A and clade B amoA genes in DNA extracts were performed using QuantStudio TM 6 Flex Real-Time PCR Systems. The community compositions for Comammox Nitrospira were studied by the cloning libraries of amoA genes method. The results showed that the abundance of Comammox clade A amoA gene in acidic paddy soil was two orders of magnitude higher than that in neutral paddy soil ( P <0.05), and the abundance of Comammox clade B in acidic paddy soil was significantly higher than that in neutral paddy soil ( P <0.05); the abundance of Comammox clade A amoA gene in acidic paddy soil was 60 times higher than that of clade B, whereas the abundance ratio of Comammox clade A and clade B amoA genes in neutral paddy soil was about two times higher. These results indicated that soil pH significantly affected the abundance of Comammox Nitrospira . The results of cloning and sequencing showed that the Comammox in neutral paddy soil was mainly N. inopinata , which belonged to clade A; no strain belonging to clade B was annotated. Comammox clade A in acidic paddy soil was mainly Composed of N. inopinata and N. nitrosa , and clade B was mainly uncultured bacterium (FN395328). The results indicated that soil pH was an important factor in shaping Comammox Nitrospira community structure. Comammox Nitrospira were detected in all soil samples, and Comammox clade A had a preference for acidic environments. It seemed that species from N. nitrosa possessed the ecological niche of low pH environments, whereas species from N. inopinata preferred to live in neutral environments. In conclusion, pH had a significant effect on the abundance and community structure of Comammox Nitrospira , which was one of the important factors affecting the niche differentiation of Comammox Nitrospira .

Phytochemical investigation of Lycopodium cernuum L. afforded seven undescribed serratene triterpenoids named 3β, 21β-dihydroxyserra-14-en-24-oic acid-3β-(5'-hydroxybenzoate) (1), 3β, 21β, 24-trihydroxyserrat-14-en-3β-(5'-hydroxyl benzoate) (2), 3β, 14α, 15α, 21β-tetrahydroxyserratane-24-methyl ester (3), 3β, 14α, 21β-trihydroxyserratane-15α-(4'-methoxy-5'-hydroxybenzoate)-24-methyl ester (4), 3β, 14α, 21β-trihydroxyserratane-15α-(4'-methoxy-5'-hydroxybenzoate) (5), 3β-hydroxy-21β-acetate-16-oxoserrat-14-en-24-oic acid (6), 3β, 21β-dihydroxy-16α, 29-epoxyserrat-14-en-24-methyl ester (7), together with eleven known compounds (8-18), whose chemical structures were elucidated through spectroscopic analysis of HRESIMS, 1D NMR, 2D NMR and comparison between the literature. All compounds were evaluated for their α-glucosidase inhibitory activity for the first time. The results showed that compounds 1, 2, 4, 5, 6, 10, 13, 15, and 16 were among the most potent α-glucosidase inhibitors, with IC 50 values ranging from 23.22 ± 0.64 to 50.65 ± 0.82 μM. Structure-activity relationship (SAR) studies indicated that the combined properties of the 5-hydroxybenzoate moiety at C-3, β-OH at C-21, COOH- at C-24, and Δ 14,15 groups enabled an increase in the α-glucosidase inhibitory effect. In addition, molecular docking studies showed that the potential inhibitors mainly interact with key amino acid residues in the active site of α-glucosidase through hydrogen bonds and hydrophobic forces., (Copyright © 2021. Published by Elsevier Ltd.)

Nitrogen metabolism pathways mediated by microorganisms play an important role in maintaining the structure and functional stability of soil ecosystems. Clarifying the relationships between microbial communities and nitrogen metabolism pathways can expand our understanding of nitrogen metabolism pathways at a microscopic level. However, the horizontal gene transfer of microorganisms means that taxonomy-based methods cannot be easily applied. A growing number of studies have shown that functional traits affect community construction and ecosystem functions. Using methods based on functional traits to study soil microbial communities can, therefore, better characterize nitrogen metabolism pathways. Here, five typical forest soils in China, namely black soil(Harbin, Heilongjiang), dark-brown earth(Changbaishan, Jilin), yellow-brown earth(Wuhan, Hubei), red earth(Fuzhou, Fujian), and humid-thermo ferralitic soil(Ledong, Hainan), were selected to study the traits of nitrogen metabolism pathways using metagenomic technology combined with the trait-based methods. The studied nitrogen metabolism pathways were ammonia assimilation, nitrate dissimilatory reduction, nitrate assimilatory reduction, denitrification, nitrification, nitrogen fixation, and anaerobic ammonia oxidation. The results showed that bacteria dominated the metagenomic library, accounting for 98.02% of all the sequences. Across all domains, the most common pathway was ammonia assimilation. For example, an average of 2830 ammonia assimilation pathway genes were detected for every million annotated bacterial sequences. In comparison, nitrogen fixation and anaerobic ammonia oxidation were the least detected pathways, accounting for 28.3 and 10.7 per million sequences, respectively. Different microorganisms can participate in a same nitrogen metabolism pathway, and the community structure of different soils was variable. The five typical forest soils in China show the same microbial nitrogen metabolism pathway traits; however, the community structure of the microorganisms mediating these processes was found to vary.

Background: This study assessed the reliability and validity of the modified Unified Classification System for femur fractures after hip arthroplasty., Methods: Four hundred and two cases were evaluated by 6 observers, 3 experts and 3 trainee surgeons. Each observer read the radiographs on 2 separate occasions and classified each case as to its type. Reliability was assessed by looking at the intraobserver and interobserver agreement using the Kappa statistic. Validity was assessed within the B group by looking at the agreement between the radiographic classification and the intraoperative findings. Interobserver and intraobserver agreement and validity were analyzed, using weighted kappa statistics., Results: The mean k value for interobserver agreement was found to be 0.882 (0.833-0.929) for consultants (almost perfect agreement) and 0.776 (0.706-0.836) for the trainees (substantial agreement). Intraobserver k values ranged from 0.701 to 0.972, showing substantial to almost perfect agreement. Validity analysis of 299 type B cases revealed 89.854% agreement with a mean k value of 0.849 (0.770-0.946) (almost perfect agreement)., Conclusions: This study has shown that the modified Unified Classification System is reliable and valid. We believe it is useful to improve the judgment of the implant stability, and establish the therapeutic strategy for periprosthetic femoral fracture., Competing Interests: Declaration of Competing Interest The authors declare that they have no conflict of interest., (Copyright © 2020 The Japanese Orthopaedic Association. Published by Elsevier B.V. All rights reserved.)

Two hitherto unknown highly modified abietane diterpenoids, namely salviapritin A ( 1 ) and salviapritin B ( 2 ), were isolated from the ethanol extract of Salvia prionitis , together with 17 known compounds. Their chemical structures were established by extensive spectroscopic methods (ESIMS, HRESIMS, 1D and 2D NMR) and by comparison of their NMR data with those of related analogues. Salviapritin A is the first example of a trinorabietane diterpenoid possessing an acenaphthylene skeleton from the Salvia genus. Additionally, a plausible biogenetic pathway for salviapritin B is proposed. [Formula: see text].

Two hitherto unknown iboga-type indole alkaloids, namely (3R)-7,19-di-epi-3-methoxytabernoxidine (1) and (3R,19R)-19-hydroxy-3-(2-oxopropyl)voacangine (2), together with eight known alkaloids (3-10), were isolated from the twigs and leaves of Tabernaemontana divaricata. Their structures were established on the basis of spectroscopic data interpretation, single crystal X-ray diffraction analysis and circular dichroism spectrum.

Two new triterpenoids, 3- O -(4',5'-dihydroxybenzoyl)-lup-20(29)-en ( 1 ) and 3- O -(6'-desmethysyringyl)-13α-methyl-27-norolean-14-en-3 β -ol ( 2 ), were isolated from the leaves and twigs of Orophea yunnanensis . Their structures were identified by extensive spectroscopic experiments (NMR and MS) and comparison with literature data. Compounds 1 and 2 exhibited the moderate inhibitory activity against Sclerotinia sclerotiorum , Ceratocystis fimbriata and Verticillium dahliae Kleb with MIC values from 50 to 25  μ g/mL, and also displayed the weak activity selectively against tested bacteria strains with MIC values from 100 to 50  μ g/mL.

Five new polyphenolic derivatives, sepiumols A-E (1-5), were isolated from the root barks of Periploca sepium. Their structures were elucidated by interpretation of NMR spectroscopic and mass spectrometric data. Compounds 1, 3 and 5 were found to exhibit significant antifungal activity, particularly for 3 with the remarkable activity against Gibberella saubinetii and Alternaria longipes with MIC values of 1.56 and 3.13 μg/mL (ketoconazole: 0.78 μg/mL), respectively. In addition, compounds 1, 3 and 5 also displayed significant antibacterial activity against methicillin-resistant Staphylococcus aureu with MIC values of 12.50-25 μg/mL (ciprofloxacin: 0.78 μg/mL)., (Copyright © 2019. Published by Elsevier B.V.)

A new pregnane steroid, named aspergillon A ( 1 ), together with two known compounds, (22 E ,24 R )-ergosta-5,7,22-trien-3 β -ol ( 2 ) and (22 E , 24 R )-ergosta-4,6,8(14),22-tetraen-3-one ( 3 ) were isolated from cultures of the tin mine tailings-associated fungus Aspergillus versicolor . The new structure and absolute configuration were determined with the help of extensive spectroscopic analyses and quantum chemical calculations of the electronic circular dichroism (ECD) spectra.

Increasing evidence suggests that ammonia oxidation in acidic soils is primarily catalyzed by ammonia-oxidizing archaea (AOA), while ammonia-oxidizing bacteria (AOB) drive ammonia oxidation in neutral and alkaline soils in which AOA overwhelmingly outnumber AOB. Therefore, neutral purple soil with a pH of 7.2 was selected to study the composition of the active ammoxidation microbial community with a stable isotope nucleic acid probe technique combined with cloning sequencing. Results showed that the nitrification rate was 9.68 mg·(kg·d) -1 , and AOA and AOB were abundant in neutral purple soils. By using DNA-based stable isotope probing (SIP), we gathered strong evidence of archaeal ammonia oxidation by AOA and AOB. Phylogenetic analysis indicated that the Nitrosospira Cluster 3a.1 AOB was dominant in terms of quantity at 0 days, and the Nitrosospira Cluster 3a.2 only accounted for a small part. After 56 days of cultivation, the Nitrosospira Cluster 3a.2 replaced the Nitrosospira Cluster 3a.1 as the active AOB that dominated ammonia oxidation. The AOA that predominated quantitatively at day 0 was Nitrososphaera Subcluster 9, but after cultivation this became Nitrososphaera Subcluster 3.2/3.3. Thus, the community structure of AOA and AOB changed. Active autotrophic nitrification was found in this neutral purple soil. Sequencing analysis of the 13 C-labeled DNA provided robust evidence that both archaea and bacteria played important roles in the nitrification and not all ammonia oxidizers in native soil were active in the nitrification. Phylogenetic analysis clearly showed that the dominant active archaea and bacteria during the incubation were affiliated with Nitrososphaera Subcluster 3.2/3.3 within the soil group 1.1b lineage and Nitrosospira Cluster 3a.2, respectively, which were different from the dominant ammonia oxidizers at the beginning of the incubation. These results suggest that the community structure of ammonia oxidizers can shift quickly upon changes in the substrate availability in soils.

Four hitherto unknown aristolane-type sesquiterpenes, including one novel 8,9-secoaristolane, namely secoaristolenedioic acid (1), two aristolone derivatives, namely 1α,2β-dihydroxyaristolone (2), 9-epidebilon (3), and one rare aristolane-chalcone hybrid, namely 3'-hydroxynardoaristolone A (4) were isolated from the ethanol extract of the roots and rhizomes of Nardostachys chinensis. Their structures were elucidated on the basis of extensive spectroscopic analysis. In addition, the structure of aristolanhydride, recently isolated from the same species, was corrected by reanalysis of the published NMR data.

Background: This study assessed the surgical outcomes of Lisfranc injuries accompanied by multiple metatarsal fractures. Metatarsal fractures here refers to metatarsal head, neck, and shaft (including shaft fractures accompanied by fractures of the base) fractures, as well as mixed (i.e., segmental fracture) fractures, as seen on imaging studies., Methods: Between 2002 and 2015, one hundred and seventy-six patients were followed-up for a mean of 92 months, including eight patients who underwent secondary arthrodesis due to severe arthritis after ORIF. All the patients underwent surgical fusion (primary partial arthrodesis, PPA; n = 78) or non-fusion (percutaneous or open reduction and internal fixation, ORIF; n = 98) procedures and the outcomes were evaluated by clinical examinations, radiography, visual analogue scale (VAS) pain score, the American Orthopaedic Foot and Ankle Society (AOFAS) midfoot score, the Foot and Ankle Outcome Score (FAOS), and the Short Form (SF)-36 physical and SF-36 mental questionnaires. The parameters between the fusion and non-fusion groups were analyzed by repeated-measures ANOVA. Statistically significant differences between the two groups were then further analyzed using a two-independent-samples t-test., Results: Anatomical reduction was achieved in 161 patients. At the last follow-up, the mean AOFAS score was 74.67 (range: 39-91) in the non-fusion group and 82.79 (range: 67-97) in the fusion group (P = 0.003). The PPA and ORIF groups differed significantly with respect to the VAS pain score (1.93 vs. 1.21), the SF-36 physical (75.87 vs. 80.90) and mental (75.76 vs. 81.33) components, and the FAOS pain (72.74 vs. 84.06), symptoms (71.87 vs. 82.49), activities of daily life (ADLs: 73.12 vs. 81.54), sport/recreation (sport/rec: 57.99 vs. 73.23), and quality of life (QoL: 79.95 vs. 86.67) components. In the ORIF group, 23 patients had mild/moderate post-traumatic osteoarthritis., Conclusions: With longer and more conservative postoperative management, fusion results in a better outcome than non-fusion in the treatment of Lisfranc injuries accompanied by multiple metatarsal fractures., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Background: Reconstruction of Myerson type III (defect size more than 5 cm) chronic Achilles tendon ruptures (CATRs) is a surgical challenge due to its large Achilles tendon defect. This study aims to describe our operative technique for Myerson type III CATR and its clinical outcomes., Patients and Methods: From May 2012 to April 2015, we treated seven patients (6 males, 1 female) with Myerson type III CATR using semitendinosus tendon and gracilis tendon autograft. The mean age was 47.3 years (range: 37-56). Patients were followed for a mean time of 31.3 months. All patients' defect size between Achilles ends after debridement was more than 5 cm and hence classified as Myerson type III. The clinical outcomes were evaluated by visual analog scale (VAS) for pain, American Orthopaedic Foot and Ankle Society (AOFAS) ankle and hindfoot score, Achilles tendon total rupture score (ATRS), and the Short Form 36 (SF-36)., Results: All patients reported good postoperative clinical outcomes. The average AOFAS score increased from 54.29 points (range: 46-65 points) preoperatively to 97.57 points (range: 90-100 points) at last follow-up. The average ATRS increased from 51.43 points (range: 40-61 points) preoperatively to 92.71 points (range: 83-100 points) at last follow-up. And the average VAS for pain was 0 at the last follow-up. The mean value of SF-36 physical increased from 32.14 points (range: 25-35 points) to 90 points (range: 80-95 points). And the mean value of SF-36 mental was improved from 37.14 points (range: 32-40 points) to 90.86 points (range: 84-96 points)., Conclusions: Semitendinosus tendon combined gracilis tendon autograft is a safe and effective technique in the reconstruction of Myerson type III CATR.

Background: The Unified Classification System (UCS) for Periprosthetic femoral fractures (PPFF) still has some limitations., Methods: We retrieved 18 previous classifications for PPFF based on systematic review of the literature, and also retrospectively analyzed 402 cases with PPFF. 46 cases (11.4%) were identified as beyond the classification scope of the original UCS., Results: We modified the UCS as follows: (1) add two new B2 subtypes: B2PALT/B2PAGT (i.e., the pseudo ALT/AGT: Fracture in trochanter region including a segment of the proximal medial/lateral femoral cortex); (2) add a new FS category to encompass stem fracture alone or accompanied by PPFF, with FSO designating this fracture with stem fracture alone, FS1 designating this fracture with the proximal portion of the fractured femoral prosthesis being stable, FS2 designating this fracture with the proximal portion of the fractured femoral prosthesis being loose and the surrounding bone quality being good, and FS3 designating this fracture with the proximal portion of the fractured femoral prosthesis being loose and the bone bed being of poor quality; and (3) delete Type F which does not apply to the femur. Thus, using our modification of the UCS, among the 46 cases, we found thirty-five B2PALT, two B2PAGT, three FSO, one FS1, two FS2 and three SF3., Conclusions: Compared to the original UCS, our modified version is more comprehensive. We believe it is useful to improve the judgment of the implant stability, and establish the therapeutic strategy for PPFF., (Copyright © 2018 The Japanese Orthopaedic Association. Published by Elsevier B.V. All rights reserved.)

The discovery of the complete ammonia-oxidizing microbes, Comammox Nitrospira , had fundamentally changed our perspective on traditional nitrification. The microbe also played a potentially under-appreciated role in the biogeochemical N cycle and provided a new dimension for the research of nitrification. To investigate the abundance of Comammox in different ecosystems was urgently needed. In the present study, three treatments with different quantities of fertilization in a paddy soil (blank control, NPK and 1.5 NPKS) to investigate the nitrification and amoA gene abundance for nitrifying microorganisms, especially for the complete ammonia oxidizing bacteria (Comammox Nitrospira ). The results showed that:① Both Comammox Clade A and Comammox Clade B were detected in all three treatments, and the abundance of Comammox Clade A were 9.0×10 7 , 1.7×10 8 , 7.2×10 8 copies·g -1 (dry soil), respectively, and for Comammox Clade B were 1.5×10 7 , 1.2×10 7 , 1.7×10 7 copies·g -1 (dry soil), respectively. ② The abundances of both ammonia-oxidizing archaea (AOA)in the three fertilizers was 1.5×10 7 -1.2×10 8 copies·g -1 (dry soil), and the ammonia-oxidizing bacteria (AOB) in the three fertilizers was 2.0×10 5 -9.3×10 7 copies·g -1 (dry soil), lower than the abundance of the Comammox. The ratio of Comammox to AOA was 7.2, and the ratio for Comammox to AOB was 524.4 for blank control, were greater than NPK and 1.5 NPKS treatments. ③ The ratio of Comammox Clade A to Comammox Clade B showed an increasing trend with the increase in fertilizer application, at 6.1, 14.4 and 43.1, respectively. ④ For NPK and 1.5 NPKS treatments, Comammox Clade A amoA gene copies were 1.9 and 8.0 times higher than that of the blank control treatment respectively, and the numbers for AOA significantly increased to 3.2 and 7.2 times that of the blank control. The AOB gene copy numbers increased by two orders of magnitude compared with the blank control. In addition, the nitrification potential increased with the increase in N fertilizer application; however, the effects of different fertilizer treatments on Comammox Clade B were not significant. Results indicated that Comammox was widely distributed in the neutral purple paddy soil and was higher in abundance than AOA or AOB, which implied that Comammox-especially Clade A-may contribute to the nitrification of paddy soil.

Six hitherto unknown prenylated 2-phenoxychromones, epimedonin G (1), 7-O-methylepimedonin G (2), and epimedonins H-K (3-6), and two new prenylflavonoids, epimedonin L (7) and 3″-O-desmethylspinorhamnoside (8), were isolated from an ethanol extract of the aerial parts of Epimedium brevicornum. Their structures were established on the basis of spectroscopic data interpretation. Compound 7 exhibited cytotoxic activity when evaluated against four human cancer cell lines (HL-60, A-549, MCF-7, and SW-480), with IC 50 values of <10 μM. In addition, the structures of epimedonins A and B (9a, 10a), recently isolated from E. koreanum, were corrected by reanalysis of the published NMR data.

Acidic forest peat soil in Xiaoxing'an Mountain was used to investigate the type and key drivers of nitrification by carrying out nitrification incubation after adding 10 mL·L -1 C 2 H 2 and different amounts of (NH 4 ) 2 SO 4 (0, 1.2, 6.0 mmol N·kg -1 ). Results showed that strong mineralization (0.9-1.4 mg N·kg -1 ·d -1 ) and nitrification (0.4-0.6 mg N·kg -1 ·d -1 ) after 2 weeks of incubation were observed for both nitrogen and no nitrogen treatments, and no significant difference was observed for different (NH 4 ) 2 SO 4 application treatments. For C 2 H 2 treatment, there was relatively stronger mineralization (0.8 mg N·kg -1 ·d -1 ), but no obvious nitrification (0 mg N·kg -1 ·d -1 ). These results indicated that the nitrification in acidic peat soil was mainly autotrophic, and inorganic nitrogen application did not affect nitrification rate significantly. Results also implied that the substrate (NH 3 ) for nitrification was from the organic N mineralization, rather than the (NH 4 ) 2 SO 4 application. Both ammonia-oxidizing bacteria (AOB) and archaea (AOA) abundances increased significantly during 0-14 d regardless of nitrogen application. However, no significant difference in AOB and AOA abundances for different (NH 4 ) 2 SO 4 application treatments was observed, indicating that ammonia oxidizers did not respond positively to (NH 4 ) 2 SO 4 application. Compared with the treatments without C 2 H 2 , AOB and AOA abundances did not change significantly during the incubation in C 2 H 2 treatment, suggesting that both AOA and AOB were likely the key players in nitrification in the acidic peat soil.

Four hitherto unknown polysubstituted isoflavonoids, including three isoflavans: 7,4'-dihydroxy-8,2',3'-trimethoxyisoflavan (1), 7,2',4'-trihydroxy-8,3'-dimethoxyisoflavan (2), and 7,2',4'-trihydroxy-5-methoxyisoflavan (3), and one prenylated isoflavone cudraisoflavone M (4) were isolated from the ethanol extracts of Spatholobus suberectus (for 1 and 2), Flemingia macrophylla (for 3), and Cudrania cochinchinensis (for 4), respectively. Their structures were established on the basis of extensive spectroscopic analysis. Compounds 1 and 4 exhibited weak cytotoxic activity against five human cancer cell lines (HL-60, A-549, SMMC-7721, MCF-7, and SW-480).

Nitrification is the process of microbial oxidation of ammonia to nitrate, completed by the ammonia oxidizers (AOB and AOA) and nitrite oxidizing bacteria (NOB), sequentially. For a century, we have been learning and studying the established two-step process as the unique way for nitrification. According to the kinetic theory, there should be a one-step nitrification in the environment, that is, the whole process of nitrification (from NH 3 to NO 3 - ) was completed by one microorganism, but no study could give a direct proof for the existence of this microorganism. Until the end of 2015, three different cultivated bacteria (Candidatus Nitrospira nitrosa, Candidatus Nitrospira nitrificans and Candidatus Nitrospira inopinata) and an uncultivated bacterium (Nitrospira-like orga-nism) respectively found in different environments by three research teams, were defined as complete ammonia oxidizing microorganisms (Comammox), because all of them could carry out the complete oxidation of ammonia to nitrate. The discovery of one-step nitrification and Comammox ended the 100-year-old dogma, and triggered many important scientific issues of the global nitrogen cycle, such as the ecological niche of these microorganisms in the environment and their relative contribution in nitrification. This paper made a brief overview of the discovery of one-step nitrification and Comammox.

Four hitherto unknown prenylated coumarins, namely 6″-O-β-D-apiofuranosylapterin (1), 4'-O-isobutyroylpeguangxienin (2), 6-(3-methyl-2-oxobutyroyl)-7-methoxycoumarin (3), and 6-hydroxycoumurrayin (4), were isolated from the ethanol extract of Heracleum stenopterum, Peucedanum praeruptorum, Clausena lansium, and Murraya paniculata, respectively. Their chemical structures were established on the basis of extensive spectroscopic analysis. Compound 2 exhibited in vitro cytotoxic activity against five human cancer cell lines (HL-60, A-549, SMMC-7721, MCF-7, and SW-480) with IC 50 values ranging from 15.9 to 23.2 μM., Competing Interests: The authors declare no conflict of interest.

Coastal wetlands contribute about 75% to the global oceanic CH 4 emissions, thus play a vital role in global C cycles. In this paper, we provided a perspective on researches on metabolic, phylogenetic, and ecological diversity of the methanogenic archaea and the regulating environmental factors in coastal wetlands. Because of the presence of more favorable electron acceptors such as sulfate, methanogenesis via CO 2 reduction and acetate fermentation are limited by availability of substrates, and hydrogenotrophic and acetotrophic methanogens generally express low relative abundance. In contrast, "non-competitive" substrates such as methanol and methylated compounds have been shown to contribute substantially to methane formation in coastal wetlands, and the facultative methanogens are predominant in those environments. Salinity regulates vegetation zonation and is related to SO 4 2- concentration, by regulating types of methanogenic substrates and contents of compe-titive electron acceptors, indirectly affects the structure and function of methanogens. Major uncertainties in the current studies include the following: methanogen community structure, the key environmental factors regulating methane pathway, and their effects on methane emissions in coastal wetlands.

Four hitherto unknown 6a,11b-dihydroxypterocarpans, namely pterocarpadiols A-D (1-4), were isolated from the ethanol extract of the twigs and leaves of Derris robusta. Their structures were elucidated on the basis of extensive spectroscopic analysis. Pterocarpadiols A-D are a kind of very rare 6a,11b-dihydroxypterocarpans, and their presence as markers may be helpful in chemotaxonomical classification.

Two hitherto unknown lanostane-type triterpenoids, namely scillascillol (1) and scillascillone (2), and a hitherto unknown norlanostane-triterpene glycoside, namely scillascilloside B-1 (3), were isolated from the ethanol extract of the whole plants of Scilla scilloides. Their structures were elucidated on the basis of extensive spectroscopic studies. In addition, the structure of drimiopsin D (6a) has been revised as 2,5-dimethoxy-8-methyl-1,3,6-trihydroxyxanthone (6) by reanalysis of the spectroscopic data.

Aim: To investigate the efficacy and safety of percutaneous needle decompression in the treatment of malignant small bowel obstruction (MSBO)., Methods: A prospective analysis of the clinical data of 52 MSBO patients undergoing percutaneous needle decompression was performed., Results: Percutaneous needle decompression was successful in all 52 patients. Statistically significant differences were observed in symptoms such as vomiting, abdominal distension and abdominal pain before and after treatment (81.6% vs 26.5%, 100% vs 8.2%, and 85.7% vs 46.9%, respectively; all P < 0.05). The overall significantly improved rate was 19.2% (11/52) and the response rate was 94.2% (49/52) using decompression combined with nasal tube placement, local arterial infusion of chemotherapy and nutritional support. During the one-month follow-up period, puncture-related complications were acceptable., Conclusion: Percutaneous needle intestinal decompression is a safe and effective palliative treatment for MSBO.

Three hitherto unknown taxane diterpenoids, namely baccatin VIII (1), baccatin IX (2), and baccatin X (3), along with 10 known analogues were isolated from an ethanolic extract of the twigs and leaves of Taxus yunnanensis. The new structures were characterized based on extensive spectroscopic analysis. Compounds 1 and 2 were tested for their in vitro cytotoxicity against five human tumor cell lines, and 1 exhibited inhibitory effects on HL-60 and MCF-7, with IC50 values of 3.44 and 9.67 μM, respectively.

A new acridone alkaloid, 1,3-dihydroxy-4-methoxy-10-methylacridone (1), was isolated from leaves of the plant Micromelum integerrimum, together with two known carbazole alkaloids, glycozolinol (2) and methyl carbazole-3-carboxylate (3). Their structures were elucidated by extensive spectroscopic analysis.

The electrochemical properties on solid particle surfaces in an aqueous system have found wide application in many fields. However, for some of them there are no reliable methods of determination. What is particularly worth mentioning is the surface potentials of solid particles. Though this is a most important property and a most basic parameter in colloid interface electrochemistry, no reliable method for its determination is available yet. In the present paper, based on the diffuse double-layer theory, mathematical relations are constructed between the average concentration of ions positively adsorbed in the diffuse double layer and the surface potential of solid particles, thus transforming the determination of surface potential of solid particles into that of the average concentration of ions in the diffuse double layer, and then by applying the standard relationships of Gouy-Chapman theory, the mathematical relations of the average concentration of ions in the diffuse double layer with surface charge density, electrical field strength at surface, and specific surface area of solid particles are constructed.