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A pair of new chromone derivative enantiomers, (+)-xylarichromone A (1a) and (-)-xylarichromone A (1b), were isolated from the solid fermentation of Xylaria nigripes. The planar structure of 1 was determined by extensive NMR spectroscopic data, and its absolute configuration was assigned by comparison the ECD spectra with the known chromone derivatives. Compound 1 was the first chromone derivative reported from this medicinal fungus. The neuroprotective effects of 1 against oxygen and glucose deprivation (OGD) induced pheochromocytoma-12 cells (PC12) injury was investigated.
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Ascomicetos , Cromonas , Cromonas/farmacología , Cromonas/química , Estructura Molecular , Espectroscopía de Resonancia MagnéticaRESUMEN
ETHNOPHARMACOLOGICAL RELEVANCE: Mushrooms in the genus Hericium are used as functional food and traditional medicines for a long history in East Asian countries such as China, India, Japan, and Korea. Some species of Hericium are called as monkey head mushroom (Houtougu) in China and Yamabushitake in Japan, which are traditionally considered as rare and precious health promoting food and medicinal materials for the treatment of dyspepsia, insomnia, chronic gastritis, and digestive tract tumors. THE AIM OF THE REVIEW: This review aims to summarize the ethnopharmacology and structural diversity of secondary metabolites from Hericium species, as well as the pharmacological activities of the crude extracts and pure compounds from Hericium species in recent years. MATERIALS AND METHODS: All the information was gathered by searching Scifinder, PubMed, Web of Science, ScienceDirect, Springer, Wiley, ACS, CNKI, Baidu Scholar, Google Scholar databases and other published materials (books and Ph.D. and M. Sc. Dissertations) using the keywords "Hericium", "Traditional uses", "Chemical composition", "Quality control" and "Pharmacological activity" (1971-May 2023). The species name was checked with https://www.mycobank.org/. RESULTS: The traditional uses of Hericium species were summarized, and 230 secondary metabolites from Hericium species were summarized and classified into six classes, mainly focusing on their chemical diversity, biosynthesis, biological activities. The modern pharmacological experiments in vivo or in vitro on their crude and fractionated extracts showed that the chemical components from Hericium species have a broad range of bioactivities, including neuroprotective, antimicrobial, anticancer, α-glucosidase inhibitory, antioxidant, and anti-inflammatory activities. CONCLUSIONS: The secondary metabolites discovered from Hericium species are highly structurally diverse, and they have the potential to be rich resources of bioactive fungal natural products. Moreover, the unveiled bioactivities of their crude extracts and pure compounds are closely related to critical human health concerns, and in-depth studies on the potential lead compounds, mechanism of pharmacological effects and pharmaceutical properties are clearly warranted.
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Hericium , Fitoterapia , Humanos , Etnofarmacología , Medicina Tradicional , Extractos Vegetales/uso terapéutico , Fitoquímicos/uso terapéuticoRESUMEN
Three undescribed methylsuccinic acid derivatives, xylaril acids A-C, and two undescribed enoic acid derivatives, xylaril acids D-E, were isolated from the fungus Xylaria longipes. The structures of the undescribed compounds were deduced by spectroscopic means, including HRESIMS and 1D/2D NMR spectroscopy, as well as ECD calculations. The absolute configuration of xylaril acids A was further determined by single-crystal X-ray diffraction experiments. All the isolated compounds displayed neuroprotective activities against oxygen-glucose deprivation/reperfusion injury in PC12 cells by enhancing cell viability and inhibiting cell apoptosis.
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Ascomicetos , Xylariales , Ratas , Animales , Xylariales/química , Espectroscopía de Resonancia Magnética , Estructura MolecularRESUMEN
Background and Objectives: It remains unclear whether the use of the stylet slow-pull (SP) and wet suction (WS) can improve the yield of endoscopic ultrasound-guided fine-needle biopsy compared to standard suction (SS). The aim of this study was to compare the diagnostic efficacy of the three sampling techniques when using 25G ProCore needles for solid pancreatic lesions. Materials and Methods: This multicenter single-blind randomized crossover superiority trial enrolled patients with solid pancreatic lesions (n = 300) from four digestive endoscopic centers in China. All three sampling techniques were performed on each patient using a 25G ProCore needle in a randomized sequence. The diagnostic efficacy, the specimen yield, and quality of each technique, the overall technical success rate and diagnostic yield of the 25G ProCore needle, and rate of adverse events were evaluated. Results: A total of 291 patients were analyzed. No significant difference was found in diagnostic efficiency among the three techniques (sensitivity, 82.14% vs. 75.00% vs. 77.86, P = 0.1186; accuracy, 82.82% vs. 75.95% vs. 78.69%, P = 0.1212). The SP had an inferior tissue integrity compared to the SS and WS techniques (71.82% vs. 62.55% vs. 69.76%, P = 0.0096). There was no significant difference in the degree of blood contamination among the three groups (P = 0.2079). After three passes, the overall sensitivity was 93.93%, and the accuracy was 94.16%. Conclusions: SS and WS techniques are better choices than SP technique for 25G ProCore needle, for they could provide higher specimen adequacy without increasing the amount of blood contamination. The 25G ProCore needle can provide a satisfactory diagnostic yield for solid pancreatic lesions.
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We aimed to investigate the safety and efficacy of endoscopic resection for the treatment of gastric gastrointestinal stromal tumors (GISTs) under single-channel gastroscopy and double-channel gastroscopy. We identified 154 patients with GISTs of the stomach who underwent endoscopic resection and were retrospectively analyzed at our hospital between May 2016 and March 2020, including 49 patients by single-channel gastroscopy and 105 patients by double-channel gastroscopy. We observed the clinical efficacy, complications, and safety of endoscopic resection of gastric GISTs, and the data were evaluated retrospectively. All patients underwent endoscopic resection successfully, without conversion to open surgery. In the single-channel gastroscopy group, 7 patients had lesions in the gastric cardia, 17 in the gastric fundus, 20 in the gastric corpus, and 5 in the gastric antrum. In the double-channel gastroscopy group, 13 patients had lesions in the gastric cardia, 34 in the gastric fundus, 46 in the gastric body, 10 in the gastric antrum, 1 in the pylorus, and 1 in the gastric angular incisure. The double-channel gastroscopy group had a shorter operation time than the single-channel gastroscopy group (59.9 ± 34.9 minutes vs 74.8 ± 26.7 minutes; P = .009 and P < .01, respectively), while they also had a lower perforation rate than the single-channel gastroscopy group (34.3% vs 51.0%; P = .048 and P < .05, respectively). No residual or recurrent lesions were discovered in any patients by gastroscopy reexamination. Both single-channel gastroscopy and double-channel gastroscopy can provide safe, effective, feasible endoscopic resection. However, double-channel gastroscopy has some distinct advantages in endoscopic resection.
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Tumores del Estroma Gastrointestinal , Neoplasias Gástricas , Tumores del Estroma Gastrointestinal/cirugía , Gastroscopía , Humanos , Estudios Retrospectivos , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/patología , Neoplasias Gástricas/cirugía , Resultado del TratamientoRESUMEN
Background: The systemic immune-inflammation index (SII) is a significant prognostic factor for neoplastic diseases. However, the prognostic value of SII in patients with cholangiocarcinoma (CCA) remains unclear. This meta-analysis aimed to investigate the prognostic value of preoperative SII in patients with CCA. Method: We systematically searched for relevant studies in PubMed, Scopus, EMBASE, Web of Science, PROSPERO, and Cochrane Library databases up to March 22, 2022. Hazard ratios (HRs) and 95% confidence intervals (CIs) were used to estimate the association between SII and survival outcomes, including overall survival (OS) and recurrence-free survival. Results: Five studies with 1402 patients were included in this meta-analysis to determine the prognostic value of preoperative SII. The results showed that a higher SII was associated with poor OS in patients with CCA who underwent invasive surgery (HR=1.916; 95% CI, 1.566-2.343; Z=6.329; P<0.001). The results were reliable in the subgroup analysis according to country, age, sample size, SII cutoff values, and treatment methods. Conclusions: A high preoperative SII appears to be an effective and practical method for monitoring survival in patients with CCA. Systematic Review Registration: International Platform of Registered Systematic. Review and Meta-Analysis Protocols (INPLASY), identifier INPLASY202240015.
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Phenotypic transformation and excessive proliferation of pulmonary arterial smooth muscle cells (PASMCs) play an important role in vascular remodeling during pulmonary hypertension (PH). Magnolol (5,5'-diallyl-2,2'-dihydroxybiphenyl) is the major bioactive constituent isolated from the bark of Magnolia Officinalis, which has anti-inflammatory, antioxidant, and cardiovascular protection effects. However, the effect of magnolol on the phenotypic transformation of PASMCs is still unknown. This study aims to evaluate the effects of magnolol on the phenotypic transformation of PASMCs induced by hypoxia. In vivo, Sprague Dawley rats were exposed to hypoxia (10% O2) for four weeks to establish a PH model. The results showed that hypoxia treatment led to an increase in right ventricle systolic pressure, Fulton index, collagen production, accompanied by upregulation in the expression of collagen â , collagen â ¢, OPN, PCNA, CyclinD1, p-JAK2, and p-STAT3, as well as decreases in expression of SM-22α; these changes were attenuated by magnolol. In vitro, the primary cultured PASMCs were exposed to 3% O2 for 48 h to induce phenotypic transformation. Consistent with the findings in vivo, magnolol treatment could prevent the phenotypic transformation and hyperproliferation of PASMCs induced by hypoxia, accompanied by downregulation in the expression of p-JAK2 and p-STAT3. In summary, this study demonstrated that the protective effect of magnolol on PH vascular remodeling is related to the inhibition of phenotypic transformation and hyperproliferation of PASMCs by inhibiting the JAK2/STAT3 pathway.
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Hipertensión Pulmonar , Animales , Compuestos de Bifenilo , Proliferación Celular , Células Cultivadas , Hipertensión Pulmonar/inducido químicamente , Hipoxia/metabolismo , Lignanos , Miocitos del Músculo Liso/metabolismo , Arteria Pulmonar , Ratas , Ratas Sprague-Dawley , Remodelación VascularRESUMEN
BACKGROUND: The complications caused by diabetes mellitus (DM) are the focus of clinical treatment. However, little is known about diabetic enteropathy (DE) and its potential underlying mechanism. METHODS: Intestinal epithelial cells (IECs) and intestinal epithelial stem cells (IESCs) were harvested from BKS.Cg-Dock7m+/+Leprdb/JNju (DM) mice, and the expression of R-Spondin 3 (Rspo3) was detected by RT-qPCR, Western blotting, immunohistochemistry, and immunofluorescence. The role of Rspo3 in the abnormal differentiation of IECs during DM was confirmed by knockdown experiments. Through miRNA expression profiling, bioinformatics analysis, and RT-qPCR, we further analyzed the differentiation-related miRNAs in the IECs from mice with DM. RESULTS: Abnormal differentiation of IECs was observed in the mice with DM. The expression of Rspo3 was upregulated in the IECs from the mice with DM. This phenomenon was associated with Rspo3 overexpression. Additionally, Rspo3 is a major determinant of Lgr5+ stem cell identity in the diabetic state. Microarray analysis, bioinformatics analysis, and luciferase reporter assays revealed that microRNA (miR)-380-5p directly targeted Rspo3. Moreover, miR-380-5p upregulation was observed to attenuate the abnormal differentiation of IECs by regulating Rspo3 expression. CONCLUSIONS: Together, our results provide definitive evidence of the essential role of Rspo3 in the differentiation of IECs in DM.
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Diabetes Mellitus , MicroARNs , Animales , Diferenciación Celular , Células Epiteliales , Intestino Delgado , Ratones , MicroARNs/genética , TrombospondinasRESUMEN
BACKGROUND: Liver transplantation (LT) is the most effective treatment strategy for advanced liver diseases. With the increasing survival rate and prolonged survival time, the postoperative long-term complications of LT recipients are becoming an important concern. Among them, the newly developed cancer after LT is the second complication and cause of LT-related death after cardiovascular disease. At present, few papers have reported multiple primary carcinomas (MPCs) after LT. Herein, we retrospectively analyzed an MPC case with gastric cancer and lung cancer after LT. CASE SUMMARY: Herein, we retrospectively analyzed an MPC case with de novo gastric cancer and lung cancer after LT with no obvious complaints. Forty-one months after LT, the patient underwent radical distal gastrectomy (Billroth II) for intramucosal signet ring cell carcinoma, and then thoracoscopic wedge resection of the right lower lobe of the right lung and localized lymph node dissection 2 mo later. Therefore, paying attention to follow-up in LT recipients with early detection and intervention of de novo MPCs is the key to improving the survival rate and quality of life of LT recipients. CONCLUSION: De novo MPCs after LT are rare, and the prognosis is poorer. However, early detection and related intervention can significantly improve the prognosis of patients. Therefore, we recommend that liver transplant recipients should be followed and screened for newly developed malignant tumors to improve the survival rate and quality of life.
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Five pairs of undescribed naphthalenone derivative enantiomers, xylarinaps A-E, including one pair of indole naphthalenones and four pairs of naphthalene-naphthalenone dimers, were isolated from the ethyl acetate extracts of the solid fermentation of Xylaria nigripes, which has been used as a traditional Chinese medicinal fungus for the treatment of insomnia, trauma, and depression. The structures of these enantiomers were elucidated based on comprehensive spectroscopic analysis, including NMR and HRESIMS. Their absolute configurations were assigned by the experimental and calculated ECD data. The neuroprotective effects of all the compounds against damage to PC12 cells by oxygen and glucose deprivation (OGD) were evaluated by an in vitro bioassay. The results revealed that xylarinaps A, B, D, and E significantly enhanced cell viability, decreased the levels of malondialdehyde (MDA), increased the levels of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), as well as further markedly inhibiting apoptosis, which indicated that these results could be the mode of action of their neuroprotective effect.
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Fármacos Neuroprotectores , Animales , Apoptosis , Ascomicetos , Glutatión Peroxidasa/metabolismo , Glutatión Peroxidasa/farmacología , Malondialdehído , Fármacos Neuroprotectores/farmacología , Estrés Oxidativo , Células PC12 , Ratas , Superóxido Dismutasa/metabolismoRESUMEN
Long intergenic noncoding RNAs (lincRNAs) play a vital role in the occurrence and progression of cancer. The mechanism of lincRNAs in colorectal cancer (CRC) has not been fully elucidated. In this context, an integrated comparative long noncoding RNA (lncRNA) microarray technology was used to determine the expression profile of lncRNAs in CRC. The roles of LINC00908 are unclear. We found that LINC00908 was significantly upregulated in CRC. Inhibition of LINC00908 resulted in reduced cell proliferation and G1 cell cycle arrest, which was mediated by cyclin D1, cyclin-dependent kinase 4, and phosphorylated retinoblastoma. Moreover, inhibition of LINC00908-induced apoptosis through the intrinsic apoptosis signaling pathway, as shown by the activation of caspase-9 and caspase-3. Mechanistically, miR-143-3p directly bound to LINC00908. miR-143-3p expression was negatively correlated with LINC00908 expression in CRC tissue. Functional experiments revealed opposing roles for miR-143-3p and LINC00908, suggesting that LINC00908 negatively regulates miR-143-3p. Mechanistically, miR-143-3p directly targets LINC00908. The KLF5 inhibitor ML264 affected proliferation and apoptosis, indicating that LINC00908 may act as a competing endogenous RNA to facilitate the expression of the miR-143-3p target gene KLF5. Thus, LINC00908 has an important proliferative and antiapoptotic role in CRC by regulating the cell cycle and intrinsic apoptosis. LINC00908 could be a potential biomarker and a new therapeutic target for CRC.
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Apoptosis/genética , Proliferación Celular/genética , Neoplasias Colorrectales/genética , Regulación Neoplásica de la Expresión Génica/genética , Factores de Transcripción de Tipo Kruppel/genética , ARN Largo no Codificante/genética , Línea Celular , Línea Celular Tumoral , Movimiento Celular/genética , Neoplasias Colorrectales/patología , Puntos de Control de la Fase G1 del Ciclo Celular/genética , Células HCT116 , Humanos , Transducción de Señal/genética , Regulación hacia Arriba/genéticaRESUMEN
BACKGROUND: How suction technique affects endoscopic ultrasound-guided tissue acquisition (EUS-TA) remains unclear. A standardized protocol is currently lacking, with most previous studies being restricted to EUS-guided fine-needle aspiration (EUS-FNA). The research related to EUS-guided fine-needle biopsy (EUS-FNB) is sparse. AIMS: The aim of this study is to evaluate the diagnostic efficacy, cellularity, tissue acquisition, blood contamination and adverse event rate of three common suction techniques (standard suction, slow-pull, and wet suction) used for EUS-FNB of solid pancreatic masses. METHODS: This is a multicenter single-blind randomized cross-over superiority trial. A total of 300 patients with suspected pancreatic malignancy will be enrolled from digestive endoscopic centers at five large tertiary hospitals in China. All three suction techniques will be performed on each patient using a 25G ProCore needle, with the sequence of suction techniques determined by randomization. Cytological and histological specimens obtained with each of the three techniques will be assessed independently. Outcomes among the three suction techniques will be compared. DISCUSSION: To the best of our knowledge, this is the largest multicenter randomized cross-over trial designed to determine the optimal suction technique for the diagnosis of solid pancreatic masses. This study may contribute to standardizing the suction technique for EUS-FNB.
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Biopsia por Aspiración con Aguja Fina Guiada por Ultrasonido Endoscópico/métodos , Endoscopía Gastrointestinal , Neoplasias Pancreáticas/patología , Succión/métodos , China , Estudios Cruzados , Humanos , Estudios Multicéntricos como Asunto , Valor Predictivo de las Pruebas , Ensayos Clínicos Controlados Aleatorios como Asunto , Reproducibilidad de los Resultados , Método Simple CiegoRESUMEN
The problems caused by diabetes mellitus (DM) and its related complications are gaining increasing attention. In our previous study, the abnormal proliferation of small intestinal epithelial cells (IECs) were observed in diabetic mice. However, little is known regarding the potential underlying mechanism. In the present study, the abnormal proliferation of IECs in DM and the marked upregulation of metastasis associated lung adenocarcinoma transcript 1 (MALAT1) was observed. Additionally, knockdown of MALAT1 significantly reduced abnormal IESC proliferation in DM mice. Bioinformatics analysis and luciferase reporter assays revealed that microRNA (miR)1295p was directly targeted by MALAT1. Moreover, the results of the bioinformatics prediction and luciferase assays demonstrated that MALAT1 directly interacted with SRYbox 9 (SOX9). Furthermore, MALAT1 silencing was observed to attenuate the abnormal proliferation of IESCs through the SOX9mediated WNT/ßcatenin signaling pathway. Knockdown of MALAT1 downregulated SOX9 expression by binding to miR1295p, thereby inhibiting the abnormal proliferation of IESCs via the WNT/ßcatenin signaling pathway.
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Proliferación Celular , Diabetes Mellitus Experimental/metabolismo , Regulación hacia Abajo , Células Epiteliales/metabolismo , Intestino Delgado/metabolismo , MicroARNs/biosíntesis , ARN Largo no Codificante/biosíntesis , Animales , Diabetes Mellitus Experimental/patología , Células Epiteliales/patología , Intestino Delgado/patología , Masculino , RatonesRESUMEN
Nelumbinis Plumula has the traditional sedative effect,but its mechanism is unclear. In this study,the relationship between traditional sedative effect and hypnotic effect of Nelumbinis Plumula was taken as the starting point to study the hypnotic mechanism of the major medicinal components in Nelumbinis Plumula by the network pharmacology method. Targets of active Nelumbinis Plumula alkaloids were screened by Swiss Target Prediction server,TCMSP and BATMAN-TCM. Targets of hypnotic drugs approved by FDA were screened from Drug Bank,OMIM,TTD databases. The common targets were screened by GO and KEGG pathways. Cytoscape 3. 7. 1 software was used to construct the network of " active component-target-pathway-disease". The results of network analysis showed that 21 active compounds were associated with 44 targets and 28 pathways. Among them,21 compounds,35 targets and 15 pathways were predicted to be related to sedative hypnosis. Nelumbinis Plumula showed the hypnotic effect by acting on neuroactive ligand-receptor interaction pathway,regulation of actin cytoskeleton pathway,calcium signaling pathway,cholinergic synapse pathway.This study preliminarily revealed the potential active compounds and possible mechanisms of traditional sedative effect of Nelumbinis Plumula,which provided a theoretical basis for further experimental studies on medicinal materials and its mechanisms.
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Alcaloides , Medicamentos Herbarios Chinos , Hipnóticos y SedantesRESUMEN
Allochthonous (e.g., riparian) plant litter is among the organic matter resources that are important for wetland ecosystems. A compact canopy of free-floating vegetation on the water surface may allow for riparian litter to remain on it for a period of time before sinking to the bottom. Thus, we hypothesized that canopy of free-floating vegetation may slow decomposition processes in wetlands. To test the hypothesis that the retention of riparian leaf litter on the free-floating vegetation in wetlands affects their subsequent decomposition on the bottom of wetlands, a 50-day in situ decomposition experiment was performed in a wetland pond in subtropical China, in which litter bags of single species with fine (0.5 mm) or coarse (2.0 mm) mesh sizes were placed on free-floating vegetation (dominated by Eichhornia crassipes, Lemna minor, and Salvinia molesta) for 25 days and then moved to the pond bottom for another 25 days or remained on the pond bottom for 50 days. The leaf litter was collected from three riparian species, that is, Cinnamomum camphora, Diospyros kaki, and Phyllostachys propinqua. The retention of riparian leaf litter on free-floating vegetation had significant negative effect on the carbon loss, marginal negative effects on the mass loss, and no effect on the nitrogen loss from leaf litter, partially supporting the hypothesis. Similarly, the mass and carbon losses from leaf litter decomposing on the pond bottom for the first 25 days of the experiment were greater than those from the litter decomposing on free-floating vegetation. Our results highlight that in wetlands, free-floating vegetation could play a vital role in litter decomposition, which is linked to the regulation of nutrient cycling in ecosystems.
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Antithrombus is one of the effective methods to prevent and treat cardiovascular diseases. Based on the theory of traditional Chinese medicine,the author's previous research and relevant literature,it was found that the alkaloids in Houttuynia cordata has potential antithrombotic effect. However,the pharmacological substance basis and antithrombotic mechanism of H. cordata have not been clarified. In this study,molecular docking was used for virtual screening of antithrombotic alkaloids from H. cordata. Seventy alkaloids selected from H. cordata were screened in the docking ligand data-base with teen thrombosis targets with known crystal structures as the receptors. In addition,the small-molecule approved or to be approved drugs of targets from Drug Bank database were set as a positive reference with minimum score(S value) of each target's approved or to be approved drugs as threshold. The Dock module in Molecular Operating Environment(Version 2016) software was applied to screen the potential active compounds which their scores(S value) were lower than the minimum score of reference. At last the mechanism of antithrombotic effect was preliminarily revealed by compared the main active sites of the test alkaloids with original ligands and references. This study provided some useful information to development of antithrombus drugs.
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Alcaloides/farmacología , Fibrinolíticos/farmacología , Houttuynia/química , Simulación del Acoplamiento Molecular , Fitoquímicos/farmacologíaRESUMEN
In wetland ecosystems, vegetation can float freely on water surface, forming dense canopy which may play important ecological roles. This is especially true in many urban wetlands in which fluidity is low and nutrient level is high. So far, effects of free-floating vegetation on abiotic and biotic factors of wetlands have been known, while little on wetland ecosystem functions such as litter decomposition. To examine whether the canopy of free-floating vegetation on water surface will influence litter decomposition in wetlands or not, we conducted a 50-day in situ decomposition experiment in a subtropical urban pond wetland, in which litter bags of nine combinations of three mesh sizes and three litter species were put on the bottoms of total 22 ponds which were half with and half without free-floating vegetation canopy on the water surface. The ponds with and without the canopy had different water physicochemical properties. Overall, the canopy, the species identity, and the mesh size significantly decelerated mass loss and carbon loss of leaf litters while slightly on nitrogen loss. Effects of the canopy on leaf litter decomposition also showed species- and mesh size-dependent. Our results suggest that free-floating vegetation on water surface can alter water environmental factors and consequently change ecosystem functioning in wetlands.
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Hojas de la Planta/fisiología , Humedales , Biodegradación Ambiental , Carbono/metabolismo , China , Ecosistema , Nitrógeno/metabolismo , Plantas , EstanquesRESUMEN
Many ecosystems may suffer from both nutrient enrichment and exotic plant invasions simultaneously. Much has been known that nutrient inputs can promote growth and expansion of exotic invasive plants in wetlands, and that allelopathic effects of the exotic invasive plants can inhibit the growth of coexisting native plants, contributing to their invasion success. Thus, we hypothesized that allelopathic effects of exotics on natives in invaded ecosystems can be enhanced by nutrient enrichment. To test this hypothesis, we conducted two greenhouse hydroponic experiments. One is the monoculture experiment in which a widespread exotic invasive perennial Alternanthera philoxeroides and a native perennial Ludwigia peploides subsp. stipulacea in monoculture were subjected to five levels of nutrient supply. The other is the mixture experiment in which the two species in mixture were subjected to five levels of nutrient supply, each with and without activated carbon addition. Both A. philoxeroides and L. peploides grew better under higher level of nutrient availability in monoculture experiment. In the mixture experiment, A. philoxeroides formed less total and root biomass while L. peploides formed more in response to activated carbon addition and all of the responses had larger degree at higher level of nutrient availability, indicating A. philoxeroides had significant allelopathic effects on L. peploides and the effects was significantly enhanced by nutrient enrichment. Such results support our hypothesis and reveal a novel mechanism for exotic plant invasion in eutrophicated and invaded wetlands, i.e. nutrient enhancement of allelopathic effects of exotics on natives.
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Alelopatía/fisiología , Amaranthaceae/metabolismo , Especies Introducidas , Nutrientes/metabolismo , Onagraceae/metabolismo , Carbón Orgánico/metabolismo , China , HumedalesRESUMEN
This study aims to investigate effects of polymorphisms in key Th-17 immune response genes on the susceptibility to HBeAg-positive (HBeAg+) chronic hepatitis B (CHB) and response to PEG-IFNa-2α. A total of 139 patients with HBeAg+ CHB treated with PEG-IFNa-2α and 145 healthy controls were enrolled to explore the association between IL-17A, IL-17F, IL-21 and IL-23R polymorphisms and HBeAg+ CHB susceptibility, as well as treatment efficacies. Genotypes were determined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and DNA sequencing. IL-17A rs4711998 and IL-17F rs763780 may affect susceptibility to HBeAg+ CHB and response to PEG-IFNa-2α treatment. The T allele of IL-21 rs12508721 may lower HBeAg+ CHB susceptibility but enhance PEG-IFNa-2α response, and the GA genotype and the A allele of IL-23R rs11209026 may reduce the susceptibility to HBeAg+ CHB. Th17-related gene polymorphisms were linked to HBeAg+ CHB susceptibility, and rs4711998, rs763780 and rs12508721 were associated with sustained responses to PEG-IFNa-2α.