[Differences in Soil Fertility and Bacterial Community Structure Between Carbon Inputs such as Biochar and Organic Fertilizer and Their Relationship].

The potato planting area of Guizhou Province ranks second in China. However, due to factors such as climatic conditions and unbalanced fertilization, soil organic matter in potato fields is consumed rapidly and has a large deficit, which affects soil biological function and soil fertility. Biochar and organic fertilizer are effective ways to supplement foreign aid organic matter to improve soil quality. However, the differences in soil fertility and microbial community structure and their relationships under the conditions of organic fertilizer or biochar combined with chemical fertilizer are not clear. In this study, three treatments of conventional fertilization （NPK）, increased application of biochar （NPKB）, and increased application of organic fertilizer （NPKO） were set up to investigate the characteristics of potato rhizosphere soil, bacterial community composition, and diversity； to analyze the effects of these factors on the soil integrated fertility index； and to explore the direct and indirect effects of IFI on soil fertility and bacterial community structure differences between treatments and their driving factors. The results showed that soil pH, available phosphorus （AP）, available potassium （AK）, total nitrogen （TN）, organic carbon （SOC）, and C/N ratio were significantly higher in the NPKB and NPKO treatments than in the NPK treatment （P<0.05）. Soil IFI was greatest for NPKO, followed by NPKB and least for the NPK treatment. A total of 8 214 ASVs were obtained from all the soil samples, belonging to 26 phyla, 75 classes, 165 orders, 176 families, and 251 genera （excluding unidentified fungi）. Proteobacteria, Actinobacteria, and Chloroflexi were the dominant phyla, accounting for 54.85% of all ASVs. Compared to that in the NPK and NPKB treatments, the NPKO treatment had the highest bacterial diversity and number of significantly different taxa, and soil AN, AP, AK, SOC, TN, and IFI were significant correlates of bacterial diversity index （P<0.05）. Additionally, pH, TN, and SOC were significant influencers of bacterial taxa differences （P<0.05）, with importance ranked as TN （70.59%） > SOC （49.42%） > pH （27.08%）. Structural equations suggested that pH-related soil properties and bacterial community diversity were the direct pathways influencing IFI, and soil pH-related soil characteristics could also indirectly affect IFI by affecting bacterial Shannon diversity. These results indicate that soil fertility and bacterial community structure were significantly different and correlated between the biochar and organic fertilizer addition treatments and that pH and bacterial community diversity were the key factors influencing IFI, with the NPKO treatment in particular having the best effect on improving IFI. Considering the effect of soil fertilization and the functional group of bacteria, NPKO is the recommended combination for the best synergistic effect of soil fertilization, that is, N 150 kg·hm-2+P2O5 135 kg·hm-2+K2O 135 kg·hm-2+organic fertilizer 6.6 t·hm-2.

Design, synthesis and evaluation of novel ferulic acid derivatives as multi-target-directed ligands for the treatment of Alzheimer's disease.

A series of new ferulic acid derivatives were designed, synthesized and evaluated as multi-target inhibitors against Alzheimer's disease. In vitro studies indicated that most compounds showed significant potency to inhibit self-induced ß-amyloid (Aß) aggregation and acetylcholinesterase (AChE), and had good antioxidant activity. Specifically, compound 4g exhibited the potent ability to inhibit cholinesterase (ChE) (IC50, 19.7 nM for hAChE and 0.66 µM for hBuChE) and the good Aß aggregation inhibition (49.2% at 20 µM), and it was also a good antioxidant (1.26 trolox equivalents). Kinetic and molecular modeling studies showed that compound 4g was a mixed-type inhibitor, which could interact simultaneously with the catalytic anionic site (CAS) and the peripheral anionic site (PAS) of AChE. Moreover, compound 4g could remarkably increase PC12 cells viability in hydrogen peroxide-induced oxidative cell damage and Aß-induced cell damage. Finally, compound 4g had good ability to cross the BBB using the PAMPA-BBB assay. These results suggested that compound 4g was a promising multifunctional ChE inhibitor for the further investigation.

Design, synthesis and evaluation of resveratrol-indazole hybrids as novel monoamine oxidases inhibitors with amyloid-ß aggregation inhibition.

Novel hybrids with MAO and Aß (1-42) self-aggregation inhibitory activities were designed and synthesized with the employment of indazole moiety and resveratrol. The biological screening results indicated that most compounds displayed potent inhibitory activity for Aß (1-42) self-aggregation, and obvious selective inhibition to MAO-B. Among these compounds, compound 6e was the most potent inhibitor not only for hMAO-B (IC50 = 1.14 µM) but also for Aß (1-42) self-aggregation (58.9% at 20 µM). Molecular modeling and kinetic studies revealed that compound 6e was a competitive MAO-B inhibitor, which can occupy the active site of MAO-B, and interact with Aß (1-42) via π-π and cation-π stacking interactions. In addition, compound 6e had no toxicity on PC12 cells and could cross the BBB. Collectively, all these results suggested that compound 6e might be a promising multi-target lead compound worthy of further investigation.

Design, synthesis and biological evaluation of novel coumarin-N-benzyl pyridinium hybrids as multi-target agents for the treatment of Alzheimer's disease.

Combining N-benzyl pyridinium moiety and coumarin into in a single molecule, novel hybrids with ChE and MAO-B inhibitory activities were designed and synthesized. The biological screening results indicated that most of compounds displayed potent inhibitory activity for ChE and Aß (1-42) self-aggregation, and clearly selective inhibition to MAO-B over MAO-A. Of these compounds, compound 7f was the most potent inhibitor for hMAO-B, and it was also a good and balanced inhibitor to ChEs and hMAO-B (0.0373 µM for eeAChE; 2.32 µM for eqBuChE; 1.57 µM for hMAO-B). Molecular modeling and kinetic studies revealed that compound 7f was a mixed-type inhibitor, which bond simultaneously to CAS and PAS of AChE, and it was also a competitive inhibitor, which occupied the active site of MAO-B. In addition, compound 7f with no toxicity on PC12 neuroblastoma cells, showed good ability to inhibit Aß (1-42) self-aggregation and cross the BBB. Collectively, all these results suggested that compound 7f might be a promising multi-target lead candidate worthy of further pursuit.

Design, synthesis and evaluation of novel cinnamic acid derivatives bearing N-benzyl pyridinium moiety as multifunctional cholinesterase inhibitors for Alzheimer's disease.

A novel family of cinnamic acid derivatives has been developed to be multifunctional cholinesterase inhibitors against AD by fusing N-benzyl pyridinium moiety and different substituted cinnamic acids. In vitro studies showed that most compounds were endowed with a noteworthy ability to inhibit cholinesterase, self-induced Aß (1-42) aggregation, and to chelate metal ions. Especially, compound 5l showed potent cholinesterase inhibitory activity (IC50, 12.1 nM for eeAChE, 8.6 nM for hAChE, 2.6 µM for eqBuChE and 4.4 µM for hBuChE) and the highest selectivity toward AChE over BuChE. It also showed good inhibition of Aß (1-42) aggregation (64.7% at 20 µM) and good neuroprotection on PC12 cells against amyloid-induced cell toxicity. Finally, compound 5l could penetrate the BBB, as forecasted by the PAMPA-BBB assay and proved in OF1 mice by ex vivo experiments. Overall, compound 5l seems to be a promising lead compound for the treatment of Alzheimer's diseases.

Synthesis and evaluation of small molecules bearing a benzyloxy substituent as novel and potent monoamine oxidase inhibitors.

A new series of small molecules bearing a benzyloxy substituent have been designed, synthesized and evaluated for hMAO inhibitory activity in vitro. Most of the compounds were potent and selective MAO-B inhibitors, and were weak inhibitors of MAO-A. In particular, compounds 9e (IC50 = 0.35 µM) and 10e (IC50 = 0.19 µM) were the most potent MAO-B inhibitors, and exhibited the highest selectivity for MAO-B (9e, SI > 285.7-fold and 10e, SI = 146.8-fold). In addition, the structure-activity relationships for MAO-B inhibition indicated that electron-withdrawing groups in the open small molecules were more suitable for MAO-B inhibition, and substitutions at the benzyloxy of the open small molecules, particularly with the halogen substituted benzyloxy, were more favorable for MAO-B inhibition. Molecular docking studies have been done to explain the potent MAO-B inhibition of the open small molecules. Furthermore, the representative compounds 9e and 10e showed low neurotoxicity in SH-SY5Y cells in vitro. So the small molecules bearing the benzyloxy substituent could be used to develop promising drug candidates for the therapy of neurodegenerative diseases.

Metabolism of Genipin in Rat and Identification of Metabolites by Using Ultraperformance Liquid Chromatography/Quadrupole Time-of-Flight Tandem Mass Spectrometry.

The in vivo and in vitro metabolism of genipin was systematically investigated in the present study. Urine, plasma, feces, and bile were collected from rats after oral administration of genipin at a dose of 50 mg/kg body weight. A rapid and sensitive method using ultraperformance liquid chromatography coupled with electrospray ionization quadrupole time-of-flight tandem mass spectrometry (UPLC-Q/TOF MS) was developed for analysis of metabolic profile of genipin in rat biological samples (urine, plasma, feces, and bile). A total of ten metabolites were detected and identified by comparing their fragmentation patterns with that of genipin using MetaboLynx software tools. On the basis of the chromatographic peak area, the sulfated and glucuronidated conjugates of genipin were identified as major metabolites. And the existence of major metabolites G1 and G2 was confirmed by the in vitro enzymatic study further. Then, metabolite G1 was isolated from rat bile by semipreparative HPLC. Its structure was unambiguously identified as genipin-1-o-glucuronic acid by comparison of its UV, IR, ESI-MS, (1)H-NMR, and (13)C-NMR spectra with conference. In general, genipin was a very active compound that would transform immediately, and the parent form of genipin could not be observed in rats biological samples. The biotransformation pathways of genipin involved demethylated, ring-opened, cysteine-conjugated, hydroformylated, glucuronidated, and sulfated transformations.

[Study on the relationship of immune status with severity of schistosomiasis japonica in fishermen in the Dongting Lake].

OBJECTIVE: To investigate the relationship of the immune status and the intensity of infection or the severity of the hepatosplenic pathology among fishermen with schistosomiasis japonica in the Dongting Lake region. METHODS: Inquiring and physical examination (IPE), stool examination, B-ultrasonography of the liver and spleen, flow cytometry, turbidimetry and ELISA were undertaken to acquire or determine the intensity of infection (EPG in stool), pathological change in the liver and spleen and the level of cellular and humoral immunity. Data were analyzed with SPSS 10.0 statistics software. RESULTS: Compared with subjects from non-endemic area, the CD4+ T cells and the CD4+/CD8+ ratio in fishing population in the endemic area significantly decreased. The decrease of the CD4+/CD8+ ratio was more significant among population with positive stool exam and with the increase of EPG and/or severity of pathological change in the liver and spleen. Contrarily, the level of the total IgM and the anti-SEA IgG in serum from fishing population in the endemic area was significantly higher than those from non-endemic area. High level serum antibodies in those stool positives were remarkable with the increase of EPG and/or the severity of hepatosplenic pathological change. The total IgA increased considerably in the subjects with significant pathological change of the liver and spleen. A high total IgG was only detected in those stool positives. CONCLUSION: The immune status in fishermen with schistosomiasis in the Dongting Lake showed a suppressed cellular immunity and a hyper functioning humoral immune response. The imbalance of the immunity was related to the increase of the intensity of infection and the progress of the hepatosplenic pathology.

[Analysis on morbidity and chemotherapy effects of Schistosoma japonicum infection in fishermen on Dongting Lake].

OBJECTIVE: To clarify and evaluate the morbidity of schistosome infection and the effectiveness of chemotherapy among fishermen on East Dongting Lake. METHODS: Information on water-contact, history of infection and of praziquantel (PZQ) treatment among fishermen was collected. Kato-Katz method and miracidium hatching test were applied to detect the pathogens in stool specimen. Serum antibodies against soluble egg antigen (SEA) were detected with ELISA and IHA. B-ultrasonic examination was used to determine the pathological changes of liver and spleen. Chemotherapy [PZQ 40 mg/(kg x d)] was given to the fishermen followed by a re-examination after a transmission season. RESULTS: The first investigation (six months before chemotherapy) showed that among 268 people inquired, 90.7% were frequently or intermittently contacting water, 24.0% were treated with PZQ each year, 39.4% had never been treated in the recent five years. Stool positive rate was 68.1% (111/163) and the geometric mean eggs per gram feces (EPG) were 48.77. Males had a higher infection rate (76.0%) and intensity (62.97 EPG) compared with that of females (58.7% infection rate and 30.42 EPG). The highest positive rate (83.3%) was in the age group of 11 to 20 years old. The prevalence of those who frequently or intermittently contacted water and were never treated before was 76.3% (106/139) and 79.7% (51/64), respectively. Serological positive rate was 88.0% (IHA) or 78.7% (ELISA). B-ultrasound revealed 77.4% (82/106) of the fishermen showing pathological changes in liver and/or spleen due to schistosomiasis. 37.7% of the patients showed II-III stage liver fibrosis (male: 53.0%, female: 15%), 58.5% hepatomegaly and 19.8% splenomegaly. The second investigation (six months after chemotherapy with PZQ) showed a stool positive rate of 35.4% and an average EPG 36.13 in the treatment group which were considerably lower than 56.5% infection rate and 68.47 EPG in the group without treatment. In 39 patients treated, the reversion rate from egg positive to negative was 48.7%, pathological change in liver and spleen declined by 40.6%. CONCLUSION: The prevalence and morbidity of schistosomiasis in fishermen on Dongting Lake were high due to frequent exposure to the affected water, and chemotherapy can effectively reduce the prevalence, the intensity of infection and morbidity of the fishermen.