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1.
BMC Cancer ; 23(1): 1102, 2023 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-37957639

RESUMO

BACKGROUND: Pancreatic adenocarcinoma (PAAD) is an aggressive solid tumour characterised by few early symptoms, high mortality, and lack of effective treatment. Therefore, it is important to identify new potential therapeutic targets and prognostic biomarkers of PAAD. METHODS: The Cancer Genome Atlas and Genotype-Tissue Expression databases were used to identify the expression and prognostic model of protocadherin 1 (PCDH1). The prognostic performance of risk factors and diagnosis of patients with PAAD were evaluated by regression analysis, nomogram, and receiver operating characteristic curve. Paraffin sections were collected from patients for immunohistochemistry (IHC) analysis. The expression of PCDH1 in cells obtained from primary tumours or metastatic biopsies was identified using single-cell RNA sequencing (scRNA-seq). Real-time quantitative polymerase chain reaction (qPCR) and western blotting were used to verify PCDH1 expression levels and the inhibitory effects of the compounds. RESULTS: The RNA and protein levels of PCDH1 were significantly higher in PAAD cells than in normal pancreatic ductal cells, similar to those observed in tissue sections from patients with PAAD. Aberrant methylation of the CpG site cg19767205 and micro-RNA (miRNA) hsa-miR-124-1 may be important reasons for the high PCDH1 expression in PAAD. Up-regulated PCDH1 promotes pancreatic cancer cell metastasis. The RNA levels of PCDH1 were significantly down-regulated following flutamide treatment. Flutamide reduced the percentage of PCDH1 RNA level in PAAD cells Panc-0813 to < 50%. In addition, the PCDH1 protein was significantly down-regulated after Panc-0813 cells were incubated with 20 µM flutamide and proves to be a potential therapeutic intervention for PAAD. CONCLUSION: PCDH1 is a key prognostic biomarker and promoter of PAAD metastasis. Additionally, flutamide may serve as a novel compound that down-regulates PCDH1 expression as a potential treatment for combating PAAD progression and metastasis.


Assuntos
Adenocarcinoma , Neoplasias Pancreáticas , Humanos , Prognóstico , Flutamida , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/genética , RNA , Biomarcadores , Regulação Neoplásica da Expressão Gênica , Protocaderinas , Neoplasias Pancreáticas
2.
Int J Biol Macromol ; 253(Pt 7): 127349, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37838134

RESUMO

The design of flame-retardant cellulose fabrics suffered from deterioration on wearing performance and environmental issue. Here, we developed facile construction of bio-based high fire-safety cellulose fabrics (lyocell) that exploited the bio-based flame-retardant coating (APD) by adenosine triphosphate (ATP) and dicyandiamide (DCD) via ionic reaction. The rich phosphorus/nitrogen elements of APD enabled the excellent fire safety of APD/Lyocell. Specifically, the APD/Lyocell2 had a higher limiting oxygen index (LOI) value of 29.3 %, a lower peak of heat release rate (PHRR, decreasing by 66.6 %), and a reduced total heat rate (THR, lowered by 56.5 %) with respect to pure lyocell fabrics. Interestingly, the APD/Lyocell2 exhibited well flame-retardant durability via passing the vertical burning test after 100 rubs. The satisfactory flame-retardant behaviors of APD/Lyocell derived from the excellent synergistic effect on the gaseous-solid phases, where APD could release more non-flammable gasses and generate phosphoric acid, polyphosphoric acid, etc. to accelerate itself and cellulose dehydration into char residues during combustion. More importantly, the wearing performance of APD/Lyocell fabrics, such as handle, air permeability and tensile strength, etc. almost remained after treatment. The ease of operation and use of bio-based coating made it a promising option to obtain the practical lyocell fabrics with flame-retardancy.


Assuntos
Celulose , Retardadores de Chama , Trifosfato de Adenosina , Gases , Temperatura Alta
5.
Cell Mol Biol Lett ; 27(1): 28, 2022 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-35305553

RESUMO

BACKGROUND: Parecoxib plays an important role in inhibition of human cancer. However, the effect of parecoxib on esophageal squamous cell carcinoma (ESCC) is still not well known. The purpose of this study was to investigate the effect of parecoxib on ESCC and its underlying mechanism. METHODS: RNA-sequence analysis was performed to identify functional alterations and mechanisms. Cell cycle, proliferation, invasion, and migration were assessed using flow cytometry, CCK-8 assay, colony formation, transwell, and wound healing assays. Extracellular matrix (ECM) degradation was detected by substrate gel zymography and 3D cell culture assay. Western blotting was used to detect parecoxib-dependent mechanisms involving cell cycle, proliferation, invasion, and migration. Tumor formation in vivo was detected by mouse assay. RESULTS: Functional experiments indicated that parecoxib induced ESCC cell cycle arrest in G2 phase, and inhibited cell proliferation, invasion, and migration in vitro. Western blotting revealed that parecoxib downregulated the phosphorylation levels of AKT and PDK1, as well as the expression of the mutant p53, cyclin B1, and CDK1, while upregulating p21waf1. Parecoxib inhibited matrix metalloproteinase-2 (MMP2) secretion and invadopodia formation, which were related to ECM degradation. Furthermore, we found that parecoxib suppressed ESCC growth in heterotopic tumor models. CONCLUSION: Parecoxib inhibits ESCC progression, including cell cycle, proliferation, invasion, and migration, via the PDK1-AKT signaling pathway.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Animais , Linhagem Celular Tumoral , Movimento Celular , Neoplasias Esofágicas/metabolismo , Carcinoma de Células Escamosas do Esôfago/tratamento farmacológico , Carcinoma de Células Escamosas do Esôfago/metabolismo , Isoxazóis , Metaloproteinase 2 da Matriz , Camundongos , Proteínas Proto-Oncogênicas c-akt/metabolismo
6.
Cell Commun Signal ; 20(1): 35, 2022 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-35305679

RESUMO

BACKGROUND: As a class of the opioid receptors, the kappa opioid receptor (KOR) has been verified to be a potential biomarker and therapeutic target for human malignant tumors. However, a thorough understanding of whether KOR affects progression of esophageal squamous cell carcinoma (ESCC) is still lacking. This study focused on exploring the effect of knocking down KOR in ESCC and its underlying mechanism. METHODS: Bioinformatics analysis was used to compare the different expression level of OPRK1 (KOR gene) in tumor and adjacent normal tissues, and predict the relationship between KOR expression and overall survival. RNA-sequence analysis was performed to detect the altered functions and mechanisms after down regulating KOR. The in vitro and in vivo assays were used to detect the effects of down-regulated KOR on cell proliferation, migration and invasion. Substrate gel zymography and 3D cell culture assays were used to find the effect of KOR knockdown on the degradation of extracellular matrix (ECM), and immunefluorescence was performed to detect the altered cytoskeleton. Western blotting and immunohistochemistry were used to explore the underlying mechanism pathway. RESULTS: Bioinformatics analysis revealed that the expression of OPRK1 was lower in tumor tissue than that in adjacent normal tissues, and lowered expression of KOR was associated with poorer overall survival. The in vitro assays demonstrated that down-regulation of KOR enhanced ESCC proliferation, metastasis and invasion. Western blotting revealed that down-regulation of KOR could activate PDK1-AKT signaling pathway, which actively regulated the cancer progression. Down-regulation of KOR enhanced the formation of invadopodia, secretion of matrix metalloproteinase-2 (MMP2) and rearrangement of cytoskeleton, which were positively related with the invasion of ESCC. KOR knockdown enhanced the tumor invasion and elevated the AKT phosphorylation in nude mice. The AKT kinase inhibition could reverse the effect of down-regulation of KOR. CONCLUSION: KOR might act as a tumor suppressor in ESCC and down-regulation of KOR could enhance the ESCC tumor phenotype. Video Abstract.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Animais , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células/genética , Regulação para Baixo , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago/genética , Regulação Neoplásica da Expressão Gênica , Metaloproteinase 2 da Matriz/metabolismo , Camundongos , Camundongos Nus , Invasividade Neoplásica/patologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptores Opioides kappa/genética , Receptores Opioides kappa/metabolismo , Transdução de Sinais/genética
7.
Front Microbiol ; 12: 629352, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33859628

RESUMO

Thelephora ganbajun is a wild edible mushroom highly appreciated throughout China. The microbiomes of some fungal sporocarps have been studied, however, their potential functional roles currently remain uncharacterized. Here, functional gene microarrays (GeoChip 5.0) and amplicon sequencing were employed to define the taxonomic and functional attributes within three micro-niches of T. ganbajun. The diversity and composition of bacterial taxa and their functional genes differed significantly (p < 0.01) among the compartments. Among 31,117 functional genes detected, some were exclusively recorded in one sporocarp compartment: 1,334 genes involved in carbon (mdh) and nitrogen fixation (nifH) in the context; 524 genes influencing carbon (apu) and sulfite reduction (dsrB, dsra) in the hymenophore; and 255 genes involved in sulfur oxidation (soxB and soxC) and polyphosphate degradation (ppx) in the pileipellis. These results shed light on a previously unknown microbiome and functional gene partitioning in sporome compartments of Basidiomycota. This also has great implications for their potential ecological and biogeochemical functions, demonstrating a higher genomic complexity than previously thought.

8.
Ecotoxicol Environ Saf ; 213: 112042, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33607336

RESUMO

Aluminum (Al) toxicity severely decreases plant growth and productivity in acidic soil globally. Ectomycorrhizal (ECM) fungi can promote host plant's Al-tolerance by acting as a physical barrier or bio-filter. However, little information is available on the role of ECM fungus on Al immobilization with respect to Al-tolerance. This present study aimed to screen a promising indigenous ECM fungus with high Al-tolerance and to understand its role in Al immobilization related to Al-tolerance. Two ECM fungal strains (Lactarius deliciosus 2 and Pisolithus tinctorius 715) isolated from forest stands in Southwest China were cultured in vitro with 0.0, 1.0 or 2.0 mM Al addition for 21 days to compare their Al accumulation and Al-tolerance. Meanwhile, fungal mycelia were incubated in 0.037 mM Al3+ solutions, and then Al3+ concentrations in the solution were determined at time 2, 5, 10, 20, 40, 60, 120, 180, and 240 min, and the Al3+ immobilization characteristics were evaluated using the pseudo-first order, pseudo-second order and intraparticle diffusion models. Results showed that 1.0 or 2.0 mM Al3+ addition significantly increased fungal biomass production by 23% or 41% in L. deliciosus 2, not in P. tinctorius 715. Fungal Al3+ concentrations in L. deliciosus 2 and P. tinctorius 715 were significantly increased by 293% and 103% under 2.0 mM than under 1.0 mM Al3+ addition. The pH values in the culture solution were significantly decreased by 0.43 after 21 d fungus growth but no changes between these two fungi under the same Al3+ addition. Fungal Al3+ immobilization showed a three-stage trend with initially a rapid rate followed a relatively slower rate until reaching equilibrium. The pseudo-second order model was the best (R2 = 0.98 and 0.99 for L. deliciosus 2 and P. tinctorius 715) to fit the experimentally observed data among the three models. Compared to P. tinctorius 715, L. deliciosus 2 also had greater intercept value, cation exchange capacity (CEC), and extracellular Al3+ proportion in fungal mycelia. Additionally, bio-concentration on Al3+, active site numbers for Al3+, boundary layer thickness, CEC, and immobilization on the cell wall in fungal mycelia were involved in ECM fungal Al-tolerance. These results show that both ECM fungi are Al-tolerant while L. deliciosus 2 is a promising indigenous ECM isolate with higher Al-tolerance in Southwest China, and they can be hence applied to the afforestation and ecological restoration in acidic soil.


Assuntos
Alumínio/metabolismo , Basidiomycota/fisiologia , Poluentes do Solo/metabolismo , Agaricales , Basidiomycota/crescimento & desenvolvimento , Biodegradação Ambiental , Biomassa , China , Florestas , Micélio/crescimento & desenvolvimento , Micorrizas/crescimento & desenvolvimento , Micorrizas/fisiologia , Solo/química , Microbiologia do Solo
9.
Appl Environ Microbiol ; 86(8)2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32060022

RESUMO

Plant growth is often limited by highly activated aluminum (Al) and low available phosphorus (P) in acidic soil. Ectomycorrhizal (ECM) fungi can improve their host plants' Al tolerance by increasing P availability while decreasing Al activity in vitro or in hydroponic or sand culture systems. However, the effect of ECM fungi on inorganic P (IP) and labile Al in acidic soil in the field, particularly in conjunction with Al treatment, remains poorly understood. The present study aimed to determine the influence of ECM fungal association on the mobilization of IP and labile Al in rhizosphere soil of host plants grown in the field with external Al treatment and the underlying nutritional mechanism in plant Al tolerance. To do so, 4-week-old Pinus massoniana seedlings were inoculated with three ECM isolates (Laccaria bicolor 270, L. bicolor S238A, and L. bicolor S238N) and grown in a Haplic Alisol field with or without Al treatment for 12 weeks. Results showed that L. bicolor association enhanced the available P depletion and facilitated the mobilization of IP and labile Al, in turn improving the capacity of host plant to use Al-bound P, Ca-bound P, and occluded P, particularly when P. massoniana seedlings were inoculated with L. bicolor S238A. Inoculation with L. bicolor isolates also enhanced the solubility of labile Al and facilitated the conversion of acid-soluble Al into exchangeable Al. Our findings suggested that ECM inoculation could enhance plant Al tolerance in the field by mobilizing IP to improve the P bioavailability but not by decreasing Al activity.IMPORTANCE Here, we reveal the underlying nutritional mechanism in plant Al tolerance conferred by ectomycorrhizal (ECM)-fungus inoculation in the field and report the screening of a promising ECM isolate to assist phytoremediation and afforestation using Pinus massoniana in acidic soil in southern China. This study advances our understanding of the contribution of ECM fungi to plant-ECM-fungus symbiosis and highlights the vital role of ECM-fungus inoculation in plant Al tolerance. In addition, the results described in the present study confirm the importance of carrying out studies in the field rather than only in vitro studies. Our findings strengthen our understanding of the role of ECM-fungus association in detecting, utilizing, and transporting unavailable nutrients in the soil to enhance host plant growth and adaptability in response to adverse habitats.


Assuntos
Alumínio/metabolismo , Laccaria/metabolismo , Fosfatos/metabolismo , Pinus/crescimento & desenvolvimento , Microbiologia do Solo , Solo/química , China , Rizosfera , Plântula/crescimento & desenvolvimento
10.
Genes Genomics ; 2018 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-30218346

RESUMO

Litchi (Litchi chinensis Sonn.) is an important subtropical fruit crop with high commercial value due to its high nutritional values and favorable tastes. However, irregular bearing attributed to unstable flowering is a major ongoing problem for litchi producers. Previous studies indicate that low-temperature is a key factor in litchi floral induction. In order to reveal the genetic and molecular mechanisms underlying the reproductive process in litchi, we had analyzed the transcriptome of buds before and after low-temperature induction using RNA-seq technology. A key flower bud differentiation associated gene, a homologue of FLORICAULA/LEAFY, was identified and named LcLFY (GenBank Accession No. KF008435). The cDNA sequence of LcLFY encodes a putative protein of 388 amino acids. To gain insight into the role of LcLFY, the temporal expression level of this gene was measured by real-time RT-PCR. LcLFY was highly expressed in flower buds and its expression correlated with the floral developmental stage. Heterologous expression of LcLFY in transgenic tobacco plants induced precocious flowering. Meantime, we investigated the sub-cellular localization of LcLFY. The LcLFY-Green fluorescent protein (GFP) fusion protein was found in the nucleus. The results suggest that LcLFY plays a pivotal role as a transcription factor in controlling the transition to flowering and in the development of floral organs in litchi.

11.
Food Nutr Bull ; 39(2): 246-259, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29281918

RESUMO

BACKGROUND: Iron and zinc deficiencies affect human health globally, especially in developing countries. Agronomic biofortification, as a strategy for alleviating these issues, has been focused on small-scale field studies, and not widely applied while lacking of cost-effectiveness analysis (CEA). OBJECTIVE: We conducted the CEA of agronomic biofortification, expressed as USD per disability-adjusted life years (DALYs) saved, to recommend a cost-effectiveness strategy that can be widely applied. METHODS: The DALYs were applied to quantify the health burden due to Fe and/or Zn deficiency and health cost of agronomic biofortification via a single, dual, or triple foliar spray of Fe, Zn, and/or pesticide in 4 (northeast, central China, southeast, and southwest) major Chinese rice-based regions. RESULTS: The current health burden by Fe or Zn malnutrition was 0.45 to 1.45 or 0.14 to 0.84 million DALYs for these 4 regions. Compared to traditional rice diets, the daily Fe and/or Zn intake from Fe and/or Zn-biofortified rice increased, and the health burden of Fe and/or Zn deficiency decreased by 28% and 48%, respectively. The cost of saving 1 DALYs ranged from US$376 to US$4989, US$194 to US$2730, and US$37.6 to US$530.1 for the single, dual, and triple foliar Fe, Zn, and/or pesticide application, respectively, due to a substantial decrease in labor costs by the latter 2 applications. CONCLUSIONS: Agronomic biofortification of rice with the triple foliar spray of Fe, Zn, and pesticide is a rapidly effective and cost-effectiveness pathway to alleviate Fe and Zn deficiency for rice-based dietary populations.


Assuntos
Deficiências Nutricionais , Alimentos Fortificados , Ferro , Oryza/química , Zinco , Adolescente , Adulto , Biofortificação , Criança , Pré-Escolar , China , Análise Custo-Benefício , Deficiências Nutricionais/dietoterapia , Deficiências Nutricionais/economia , Feminino , Humanos , Lactente , Recém-Nascido , Ferro/administração & dosagem , Deficiências de Ferro , Masculino , Adulto Jovem , Zinco/administração & dosagem , Zinco/deficiência
12.
Front Microbiol ; 7: 841, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27445991

RESUMO

Limited information is available if plant growth promoting bacteria (PGPB) can promote the growth of fruit crops through improvements in soil fertility. This study aimed to evaluate the capacity of PGPB, identified by phenotypic and 16S rRNA sequencing from a vegetable purple soil in Chongqing, China, to increase soil nitrogen (N), phosphorus (P), and potassium (K) availability and growth of kiwifruit (Actinidia chinensis). In doing so, three out of 17 bacterial isolates with a high capacity of N2-fixation (Bacillus amyloliquefaciens, XD-N-3), P-solubilization (B. pumilus, XD-P-1) or K-solubilization (B. circulans, XD-K-2) were mixed as a complex bacterial inoculant. A pot experiment then examined its effects of this complex inoculant on soil microflora, soil N2-fixation, P- and K-solubility and kiwifruit growth under four treatments. These treatments were (1) no-fertilizer and no-bacterial inoculant (Control), (2) no-bacterial inoculant and a full-rate of chemical NPK fertilizer (CF), (3) the complex inoculant (CI), and (4) a half-rate CF and full CI (1/2CF+CI). Results indicated that significantly greater growth of N2-fixing, P- and K-solubilizing bacteria among treatments ranked from greatest to least as under 1/2CF+CI ≈ CI > CF ≈ Control. Though generally without significant treatment differences in soil total N, P, or K, significantly greater soil available N, P, or K among treatments was, respectively, patterned as under 1/2CF+CI ≈ CI > CF ≈ Control, under 1/2CF+CI > CF > CI > Control or under 1/2CF+CI > CF ≈ CI > Control, indicating an improvement of soil fertility by this complex inoculant. In regards to plant growth, significantly greater total plant biomass and total N, P, and K accumulation among treatments were ranked as 1/2CF+CI ≈ CI > CF > Control. Additionally, significantly greater leaf polyphenol oxidase activity ranked as under CF > 1/2CF+CI ≈ Control ≈ CI, while leaf malondialdehyde contents as under Control > CI ≈ CF > 1/2CF+CI. In short, the applied complex inoculant is able to improve available soil N, P, and K and kiwifruit growth. These results demonstrate the potential of using a complex bacterial inoculant for promoting soil fertility and plant growth.

13.
CNS Neurosci Ther ; 22(8): 700-6, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27207183

RESUMO

AIMS: The present study was conducted to evaluate the antidepressant-like effects of ZBH2012001, a novel potential serotonin and norepinephrine reuptake inhibitor (SNRI). METHODS: Competitive binding assays, calcium flow, and cAMP detection methods were used to determine the affinity of ZBH2012001 for serotonin transporters (SERTs) and norepinephrine transporters (NETs), as well as its selectivity over dopamine transporters (DATs) and 16 other G-protein-coupled receptors (GPCRs) or iron channels. The antidepressant-like effects of ZBH2012001 were determined using the tail suspension test, forced swim test, and learned helplessness paradigm. The pharmacokinetics and acute toxicity of ZBH2012001 were also assessed. RESULTS: ZBH2012001 exhibited a moderate affinity to SERTs and NETs (Ki values were 35.3 ± 2.86 and 225 ± 26.0 nM, respectively); it had no effects on the DATs or the 16 other GPCRs or iron channels. Data from behavioral tests indicated that ZBH2012001 exhibited superior antidepressant-like effects compared with duloxetine (one of the most used SNRIs) in the three depression models. The pharmacokinetic evaluation of ZBH2012001 indicated that the absolute bioavailability value was 60.5%, and the acute toxicity test indicated that LD50 of ZBH2012001 was 346 mg/kg. CONCLUSION: These findings suggest that ZBH2012001 is a novel SNRI with superior antidepressant-like effects, lower acute toxicity and a better pharmacokinetic profile compared with duloxetine. Thus, ZBH2012001 may have potential therapeutic effects in depression disorders.


Assuntos
Antidepressivos/uso terapêutico , Depressão/tratamento farmacológico , Inibidores da Recaptação de Serotonina e Norepinefrina/uso terapêutico , Análise de Variância , Animais , Antidepressivos/química , Benzodioxóis/farmacologia , Benzodioxóis/uso terapêutico , Cálcio/metabolismo , AMP Cíclico/metabolismo , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Cloridrato de Duloxetina/farmacologia , Células HEK293 , Desamparo Aprendido , Elevação dos Membros Posteriores , Humanos , Concentração Inibidora 50 , Locomoção/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos ICR , Ligação Proteica/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Inibidores da Recaptação de Serotonina e Norepinefrina/química , Natação/psicologia , Tiofenos/farmacologia , Tiofenos/uso terapêutico
14.
Environ Sci Pollut Res Int ; 23(6): 5442-50, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26566613

RESUMO

Changes in soil exchangeable cations relative to soil acidification are less studied particularly under long-term cash crop plantation. This study investigated soil acidification in an Ali-Periudic Argosols after 10-year (2002-2012) long-term continuous tobacco plantation. Soils were respectively sampled at 1933 and 2143 sites in 2002 and 2012 (also 647 tobacco plants), from seven tobacco plantation counties in the Chongqing Municipal City, southwest China. After 10-year continuous tobacco plantation, a substantial acidification was evidenced by an average decrease of 0.20 soil pH unit with a substantial increase of soil sites toward the acidic status, especially those pH ranging from 4.5 to 5.5, whereas 1.93 kmol H(+) production ha(-1) year(-1) was mostly derived from nitrogen (N) fertilizer input and plant N uptake output. After 1 decade, an average decrease of 27.6 % total exchangeable base cations or of 0.20 pH unit occurred in all seven tobacco plantation counties. Meanwhile, for one unit pH decrease, 40.3 and 28.3 mmol base cations kg(-1) soil were consumed in 2002 and 2012, respectively. Furthermore, the aboveground tobacco biomass harvest removed 339.23 kg base cations ha(-1) year(-1) from soil, which was 7.57 times higher than the anions removal, leading to a 12.52 kmol H(+) production ha(-1) year(-1) as the main reason inducing soil acidification. Overall, our results showed that long-term tobacco plantation not only stimulated soil acidification but also decreased soil acid-buffering capacity, resulting in negative effects on sustainable soil uses. On the other hand, our results addressed the importance of a continuous monitoring of soil pH changes in tobacco plantation sites, which would enhance our understanding of soil fertility of health in this region.


Assuntos
Nicotiana/crescimento & desenvolvimento , Solo/química , Biomassa , Cátions/análise , China , Fertilizantes/análise , Concentração de Íons de Hidrogênio , Nitrogênio/análise , Nicotiana/química
15.
Mycorrhiza ; 25(2): 121-30, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25033923

RESUMO

Glomalin-related soil protein (GRSP) is beneficial to soil and plants and is affected by various factors. To address whether mycorrhizal-induced GRSP and relevant soil enzymes depend on external P levels, a pot study evaluated effects of the arbuscular mycorrhizal fungus (AMF) Funneliformis mosseae on GRSP production and soil enzyme activities. Three GRSP categories, as easily-extractable GRSP (EE-GRSP), difficultly-extractable GRSP (DE-GRSP), and total (EE-GRSP + DE-GRSP) GRSP (T-GRSP), were analyzed, together with five enzyme activities (ß-glucosidase, catalase, peroxidase, phosphatase, polyphenol oxidase) in the rhizosphere of trifoliate orange (Poncirus trifoliata) grown under 0, 3, and 30 mM KH2PO4 in a sand substrate. After 4 months, root AM colonization and substrate hyphal length decreased with increasing P levels. Shoot, root, and total biomass production was significantly increased by AM colonization, regardless of P levels, but more profound under 0 mM P than under 30 mM KH2PO4. In general, production of these three GRSP categories under 0 or 30 mM KH2PO4 was similar in non-mycorrhizosphere but decreased in mycorrhizosphere. Mycorrhization significantly increased the production of EE-GRSP, DE-GRSP and T-GRSP, soil organic carbon (SOC), and activity of substrate ß-glucosidase, catalase, peroxidase, and phosphatase, but decreased polyphenol oxidase activity, irrespective of P levels. Production of EE-GRSP, DE-GRSP, and T-GRSP significantly positively correlated with SOC and ß-glucosidase, catalase, and peroxidase activity, negatively with polyphenol oxidase activity, but not with hyphal length or phosphatase activity. These results indicate that AM-mediated production of GRSP and relevant soil enzyme activities may not depend on external P concentrations.


Assuntos
Citrus/microbiologia , Proteínas Fúngicas/metabolismo , Glicoproteínas/metabolismo , Micorrizas/enzimologia , Fosfatos/metabolismo , Rizosfera , Microbiologia do Solo , Solo/química , Citrus/crescimento & desenvolvimento , Citrus/metabolismo , Micorrizas/crescimento & desenvolvimento , Micorrizas/metabolismo , Fosfatos/análise
16.
Molecules ; 19(12): 19718-31, 2014 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-25438082

RESUMO

In an attempt to improve the antitumor activity and reduce the side effects of irinotecan (2), novel prodrugs of SN-38 (3) were prepared by conjugating amino acids or dipeptides to the 10-hydroxyl group of SN-38 via a carbamate linkage. The synthesized compounds completely generated SN-38 in pH 7.4 buffer or in human plasma, while remaining stable under acidic conditions. All prodrug compounds demonstrated much greater in vitro antitumor activities against HeLa cells and SGC-7901 cells than irinotecan. The most active compounds, 5h, 7c, 7d, and 7f, exhibited IC50 values that were 1000 times lower against HeLa cells and 30 times lower against SGC-7901 cells than those of irinotecan, and the inhibitory activities of these prodrugs against acetylcholinesterase (AchE) were significantly reduced, with IC50 values more than 6.8 times greater than that of irinotecan. In addition, compound 5e exhibited the same level of tumor growth inhibitory activity as irinotecan (CPT-11) in a human colon xenograft model in vivo.


Assuntos
Camptotecina/análogos & derivados , Pró-Fármacos/síntese química , Pró-Fármacos/farmacologia , Animais , Camptotecina/síntese química , Camptotecina/química , Camptotecina/farmacologia , Camptotecina/uso terapêutico , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Inibidores da Colinesterase/farmacologia , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/patologia , Estabilidade de Medicamentos , Humanos , Concentração de Íons de Hidrogênio , Irinotecano , Camundongos Nus , Pró-Fármacos/química , Pró-Fármacos/uso terapêutico , Ensaios Antitumorais Modelo de Xenoenxerto
17.
Muscle Nerve ; 50(2): 235-43, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24273088

RESUMO

INTRODUCTION: Acellular nerve grafts are good candidates for nerve repair, but the clinical outcome of grafting is not always satisfactory. We investigated whether etifoxine could enhance nerve regeneration. METHODS: Seventy-two Sprague-Dawley rats were divided into 3 groups: (1) autograft; (2) acellular nerve graft; and (3) acellular nerve graft plus etifoxine. Histological and electrophysiological examinations were performed to evaluate the efficacy of nerve regeneration. Walking-track analysis was used to examine functional recovery. Quantitative polymerase chain reaction was used to evaluate changes in mRNA level. RESULTS: Etifoxine: (i) increased expression of neurofilaments in regenerated axons; (ii) improved sciatic nerve regeneration measured by histological examination; (iii) increased nerve conduction velocity; (iv) improved walking behavior as measured by footprint analysis; and (v) boosted expression of neurotrophins. CONCLUSIONS: These results show that etifoxine can enhance peripheral nerve regeneration across large nerve gaps repaired by acellular nerve grafts by increasing expression of neurotrophins.


Assuntos
Regeneração Nervosa/efeitos dos fármacos , Oxazinas/uso terapêutico , Neuropatia Ciática/tratamento farmacológico , Neuropatia Ciática/cirurgia , Transplante Autólogo/métodos , Animais , Modelos Animais de Doenças , Estimulação Elétrica , Potenciais Evocados/efeitos dos fármacos , Expressão Gênica/efeitos dos fármacos , Expressão Gênica/fisiologia , Fator Neurotrófico Derivado de Linhagem de Célula Glial/genética , Fator Neurotrófico Derivado de Linhagem de Célula Glial/metabolismo , Locomoção/efeitos dos fármacos , Masculino , Fator de Crescimento Neural/genética , Fator de Crescimento Neural/metabolismo , Regeneração Nervosa/fisiologia , Condução Nervosa/efeitos dos fármacos , Condução Nervosa/fisiologia , Proteínas de Neurofilamentos/metabolismo , Oxazinas/farmacologia , Ratos , Ratos Sprague-Dawley , Recuperação de Função Fisiológica , Pele/inervação , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo
18.
Mol Med Rep ; 8(1): 75-80, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23670018

RESUMO

Nerve regeneration and functional recovery are major issues following nerve tissue damage. Etifoxine is currently under investigation as a therapeutic strategy for promoting neuroprotection, accelerating axonal regeneration and modulating inflammation. In the present study, a well­defined PC12 cell model was used to explore the underlying mechanism of etifoxine­stimulated neurite outgrowth. Etifoxine was found to promote glial­derived growth factor (GDNF)­induced neurite outgrowth in PC12 cells. Average axon length increased from 50.29±9.73 to 22.46±5.62 µm with the use of etifoxine. However, blockage of GDNF downstream signaling was found to lead to the loss of this phenomenon. The average axon length of the etifoxine group reduces to a normal level after the blockage of the GDNF family receptor α1 (GFRα1) and receptor tyrosine kinase (RETS) receptors (27.46±3.59 vs. 22.46±5.62 µm and 25.31±3.68 µm vs. 22.46±5.62 µm, respectively, p>0.05). In addition, etifoxine markedly increased GDNF mRNA and protein expression (1.55­ and 1.36-fold, respectively). However, blockage was not found to downregulate GDNF expression. The results of the current study demonstrated that etifoxine stimulated neurite outgrowth via GDNF, indicating that GDNF represents a key molecule in etifoxine­stimulated neurite outgrowth in PC12 cells.


Assuntos
Ansiolíticos/farmacologia , Fator Neurotrófico Derivado de Linhagem de Célula Glial/genética , Neuritos/efeitos dos fármacos , Neuritos/metabolismo , Oxazinas/farmacologia , Animais , Axônios/efeitos dos fármacos , Axônios/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Fator Neurotrófico Derivado de Linhagem de Célula Glial/metabolismo , Células PC12 , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos
19.
PLoS One ; 7(12): e53170, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23285263

RESUMO

Lung cancers express the cholinergic autocrine loop, which facilitates the progression of cancer cells. The antagonists of mAChRs have been demonstrated to depress the growth of small cell lung cancers (SCLCs). In this study we intended to investigate the growth inhibitory effect of R2HBJJ, a novel muscarinic antagonist, on non-small cell lung cancer (NSCLC) cells and the possible mechanisms. The competitive binding assay revealed that R2HBJJ had a high affinity to M3 and M1 AChRs. R2HBJJ presented a strong anticholinergic activity on carbachol-induced contraction of guinea-pig trachea. R2HBJJ markedly suppressed the growth of NSCLC cells, such as H1299, H460 and H157. In H1299 cells, both R2HBJJ and its leading compound R2-PHC displayed significant anti-proliferative activity as M3 receptor antagonist darifenacin. Exogenous replenish of ACh could attenuate R2HBJJ-induced growth inhibition. Silencing M3 receptor or ChAT by specific-siRNAs resulted in a growth inhibition of 55.5% and 37.9% on H1299 cells 96 h post transfection, respectively. Further studies revealed that treatment with R2HBJJ arrested the cell cycle in G0/G1 by down-regulation of cyclin D1-CDK4/6-Rb. Therefore, the current study reveals that NSCLC cells express an autocrine and paracrine cholinergic system which stimulates the growth of NSCLC cells. R2HBJJ, as a novel mAChRs antagonist, can block the local cholinergic loop by antagonizing predominantly M3 receptors and inhibit NSCLC cell growth, which suggest that M3 receptor antagonist might be a potential chemotherapeutic regimen for NSCLC.


Assuntos
Álcoois Benzílicos/farmacologia , Carcinoma Pulmonar de Células não Pequenas/patologia , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Neoplasias Pulmonares/patologia , Antagonistas Muscarínicos/farmacologia , Quinuclidinas/farmacologia , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Álcoois Benzílicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Avaliação Pré-Clínica de Medicamentos , Feminino , Fase G1/efeitos dos fármacos , Cobaias , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Modelos Biológicos , Antagonistas Muscarínicos/uso terapêutico , Quinuclidinas/uso terapêutico , Fase de Repouso do Ciclo Celular/efeitos dos fármacos
20.
J Environ Sci (China) ; 23(2): 255-65, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21516999

RESUMO

Combined effects of ozone (03) and cadmium (Cd) on growth and physiology of winter wheat (Triticum aestivum L. cv. JM22) were determined. Wheat plants were grown without or with Cd and exposed to charcoal-filtered air (< 10 ppb O3) or elevated O3 (80 +/- 5 ppb, 7 hr/day) for 20 days. Results showed that 03 considerably depressed light saturated net photosynthetic rate (-20%), stomatal conductance (-33%), chlorophyll content (-33%), and total biomass (-29%) without Cd. The corresponding decreases were further enhanced by 45%, 56%, 60% and 59%, respectively with Cd, indicating a synergistic effect of O3 and Cd on wheat. Ozone significantly increased the activity of superoxide dismutase (46%), catalase (48%) and peroxidase (56%). However, great increases in malondialdehyde (MDA) content (2.55 folds) and intercellular CO2 concentration (1.13 folds) were noted in O3+Cd treatment compared to control. Our findings demonstrated that the increased anti-oxidative activities in wheat plants exposed to O3+Cd might not be enough to overcome the adverse effects of the combination of both pollutants as evidenced by further increase in MDA content, which is an important indicator of lipid peroxidation. Precise prediction model on O3 damages to crop should be conducted to ensure agricultural production security by considering environmental constraints in an agricultural system in peri-urban regions.


Assuntos
Poluentes Atmosféricos/toxicidade , Cádmio/toxicidade , Ozônio/toxicidade , Poluentes do Solo/toxicidade , Triticum/efeitos dos fármacos , Catalase/metabolismo , Clorofila/metabolismo , Peroxidação de Lipídeos , Malondialdeído/metabolismo , Peroxidase/metabolismo , Superóxido Dismutase/metabolismo , Triticum/enzimologia , Triticum/metabolismo
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