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1.
Ying Yong Sheng Tai Xue Bao ; 35(1): 177-185, 2024 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-38511454

RESUMO

Microbial necromass carbon (MNC) is a crucial source for stable soil carbon pool, and understanding its response to carbon inputs from both aboveground (litter) and belowground (roots) in subtropical forest soils is essential for assessing soil carbon stocks in global ecosystems. In a Castanopsis carlesii plantation at the Sanming Forest Ecosystem National Observation and Research Station in Fujian Province, we conducted an experiment with five treatments, including root removal (NR), aboveground litter removal (NL), no litter input (removals of both aboveground litter and roots, NI), double aboveground litter addition (DL), and control (CK). After seven years, we collected soil samples in the 0-10 cm soil layer to examine changes in MNC content and its contribution to soil organic carbon (SOC). Results showed that NR treatment reduced MNC, bacterial necromass carbon (BNC), and fungal necromass carbon (FNC) by 15.9%, 20.2%, and 14.5%, respectively, while other treatments did not induce significant changes. The NR, NL, NI, and DL treatments did not affect the contributions of BNC, FNC, and MNC to SOC. Correlation and path analyses revealed that litter and root carbon input treatments could alter the MNC content directly or indirectly through changing soil available substrates and microbial community structure. Our results suggested that roots exert a stronger influence on the maintenance of MNC than aboveground carbon source in the mid-subtropical plantations.


Assuntos
Ecossistema , Fagaceae , Solo/química , Carbono/análise , Microbiologia do Solo , Florestas , Bactérias
2.
J Plant Physiol ; 253: 153260, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32846310

RESUMO

The endophytic Bacillus amyloliquefaciens YTB1407 was previously reported to promote the growth of sweet potato (Ipomoea batatas cv. Yanshu 25). Here, we demonstrate in both in vitro and pot trial assays that pre-treatment with YTB1407 suspension could enhance resistance against root rot disease and black rot disease, caused by Fusarium solani Mart. Sacc. f. sp. batatas McClure and Ceratocystis fimbriata Ell. & Halst on sweet potato, respectively. When seedlings were infected with fungal pathogens at 10 days post irrigation, pre-treatment with YTB1407 suspension decreased these pathogens and YTB1407 bacterial biomass in sweet potato roots. The pre-treatment activated the expression of salicylic acid (SA)-responsive PR-1 gene, raised SA content, and reduced hydrogen peroxide (H2O2) in the host to resist F. solani, while it enhanced the expression levels of SA-responsive NPR1 and PR1 genes and increased SA content to resist C. fimbriata. The disease resistance control effect initiated by pre-treatment with YTB1407 for root rot pathogen (F. solani) was better than for black rot pathogen (C. fimbriata). The results indicated that Bacillus amyloliquefaciens YTB1407 played a pivotal role in enhancing resistance to two fungi pathogens in sweet potato, through production of some antifungal metabolites to decrease infection in the early stage as well as induction of SA-dependent systemic resistance.


Assuntos
Bacillus amyloliquefaciens/fisiologia , Resistência à Doença , Fusarium/fisiologia , Peróxido de Hidrogênio/metabolismo , Ipomoea batatas/microbiologia , Doenças das Plantas/microbiologia , Antifúngicos/metabolismo , Endófitos , Ipomoea batatas/imunologia , Doenças das Plantas/imunologia , Raízes de Plantas/imunologia , Raízes de Plantas/microbiologia , Ácido Salicílico/metabolismo , Plântula/imunologia , Plântula/microbiologia
3.
Ying Yong Sheng Tai Xue Bao ; 29(11): 3819-3828, 2018 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-30460829

RESUMO

We isolated the endophytic Bacillus amyloliquefaciens YTB1407 from the root of Panax quinquefolium, which has both biological control and growth promoting effects. To investigate its potential applications, a pot experiment of sweet potato was tested to assess the capacity of endophytic colonization of YTB1407 and the selection of its optimum concentration by investigating the performance of root characteristics on three time points in the whole early growth phase after irrigating with different concentrations of bacterial suspensions with treatment of sterile water as control. The activities of endogenous hormone IAA, ZR, t-ZR and IAA oxidase (IAAO, PPO, POD) were analyzed. The results showed that YTB1407 promoted the specific colonization of root system, the elongation of adventitious root and branch roots, and root activity in the early growth stage of sweet potato. At later growth stage, it formed greater fresh mass of absorption root and lower aboveground/root system mass ratio. YTB1407 suspensions with OD600 of 0.50 (T0.50) had more significant effect, which induced the highest fresh tuber mass and the largest effective tuber numbers of per plant at top cover stage. YTB1407 promoted the differentiation of adventitious roots into tubers at initial point of tuberization by increasing IAA content and the ratio of (t-ZR+ZR)/IAA, decreasing IAAO activity and enhancing PPO activity. Moreover, it promoted the differentiated roots into tubers at tuberization stage by keeping the higher content of IAA, lower ratio of (t-ZR+ZR)/IAA, and decreasing IAAO and PPO activities.


Assuntos
Bacillus amyloliquefaciens/fisiologia , Ácidos Indolacéticos/metabolismo , Ipomoea batatas/microbiologia , Ipomoea batatas/fisiologia , Raízes de Plantas/microbiologia
4.
Oncotarget ; 8(56): 95108-95115, 2017 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-29221115

RESUMO

This study evaluated the lnc-RNAs as biomarker to predict efficacy of gemcitabine (GEM) based chemotherapy as the first-line treatment for locally advanced or advanced pancreatic cancer patients. We selected 62 patients with GEM based chemotherapy and divided two groups according to the PFS. We found that the expression of MALAT1, HOTTIP, and PVT1 in serum had a significant difference among the two groups. Furthermore, we estimated the PFS and response rate based on the expression levels of MALAT1, HOTTIP and PVT1. The response rate of two groups showed a significant difference according to the expression levels of MALAT1, HOTTIP and PVT1. Based on the expression levels of MALAT1, HOTTIP and PVT1, the response rate of high expression of PVT1 and low expression of PVT1 was respectively 14.8% and 37.1% and 18.2% (high HOTTIP group) and 37.9% (low HOTTIP group), 10.7%(high MALAT1 group) and 41.1% (low MALAT1 group). The PFS of patients with high and low expression levels PVT1 was 2.6 months and 4.0 months (p<0.001), respectively. The PFS of patients with high and low expression levels of HOTTIP was 2.7 months and 4.1 months (p<0.001), respectively, and the PFS of patients with high and low expression levels of MALAT1 was 3.0 months and 3.7 months (P=0.026), respectively. The results suggest that MALAT1, HOTTIP and PVT1 as predictors to predict the efficacy of GEM based chemotherapy in first-line treatment of pancreatic cancer patients.

6.
Phytochemistry ; 93: 154-61, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23571028

RESUMO

Six pyrrolizidine alkaloids were isolated from the whole herb of Liparis nervosa together with two previously known ones. Their structures were elucidated by extensive spectroscopic analyses and chemical reactions. The cytotoxicity of the isolates was evaluated against A549, HepG2, and MCF-7 human cancer cell lines; however, no significant growth inhibition was observed. All compounds were evaluated for the inhibition of LPS-induced nitric oxide (NO) production in RAW264.7 macrophages, and most significantly inhibited NO production with IC50 values in the range of 2.16-38.25 µM.


Assuntos
Lipopolissacarídeos/antagonistas & inibidores , Macrófagos/efeitos dos fármacos , Óxido Nítrico/antagonistas & inibidores , Orchidaceae/química , Alcaloides de Pirrolizidina/farmacologia , Animais , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Células Hep G2 , Humanos , Lipopolissacarídeos/farmacologia , Células MCF-7 , Macrófagos/metabolismo , Camundongos , Conformação Molecular , Óxido Nítrico/biossíntese , Alcaloides de Pirrolizidina/química , Alcaloides de Pirrolizidina/isolamento & purificação , Relação Estrutura-Atividade , Células Tumorais Cultivadas
7.
Planta Med ; 79(3-4): 281-7, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23322560

RESUMO

Ten new nervogenic acid derivatives (1-4, 6-11) and one known compound (5) have been isolated from Liparis nervosa. Their structures were determined using extensive spectroscopic analysis, including 1D and 2D NMR experiments. Compounds 3, 4, 9, 10, and 11 were evaluated for their cytotoxicity against A549, H460, Hela, MCF-7, Caco2, and HepG2 human cancer cell lines.


Assuntos
Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Orchidaceae/química , Células CACO-2/efeitos dos fármacos , Linhagem Celular Tumoral , Dissacarídeos/química , Ensaios de Seleção de Medicamentos Antitumorais , Células HeLa/efeitos dos fármacos , Hemiterpenos/química , Humanos , Concentração Inibidora 50 , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Parabenos/química
8.
J Nat Med ; 67(3): 647-51, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22886818

RESUMO

A novel steroidal alkaloid, suchengbeisine (1), along with two known steroidal alkaloids, N-oxide of verticinone (2) and zhebeininoside (3), were isolated from the bulbs of Fritillaria shuchengensis S. C. Chen et S. F. Yin. The structures of these compounds were elucidated by intensive spectroscopic methods, including NMR, IR, CD and MS.


Assuntos
Alcaloides/isolamento & purificação , Fritillaria/química , Fitosteróis/isolamento & purificação , Esteroides/isolamento & purificação , Alcaloides/química , Alcaloides/farmacologia , Células CACO-2 , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cevanas/isolamento & purificação , Relação Dose-Resposta a Droga , Células HeLa , Células Hep G2 , Humanos , Concentração Inibidora 50 , Células MCF-7 , Estrutura Molecular , Fitosteróis/química , Fitosteróis/farmacologia , Raízes de Plantas/química , Plantas Medicinais , Esteroides/química , Esteroides/farmacologia
9.
J Nat Med ; 67(4): 711-8, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23192327

RESUMO

From the aerial parts of Senecio dianthus, five eremophilane glucosides (1, 2, 4-6) and one new eremophilenolide (7) were isolated, together with sixteen known compounds (3, 8-22). Their structures and relative configurations were elucidated on the basis of extensive spectroscopic analysis, including HR-ESI-MS, X-ray, CD, 1D- and 2D-NMR experiments.


Assuntos
Glucosídeos/química , Naftalenos/química , Senécio/química , Linhagem Celular Tumoral , Glucosídeos/toxicidade , Humanos , Espectroscopia de Ressonância Magnética , Naftalenos/toxicidade , Sesquiterpenos Policíclicos , Sesquiterpenos
10.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 9): m1182-3, 2012 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-22969477

RESUMO

The centrosymmetric mol-ecule of the title compound, [Zn(C(16)H(11)N(6))(2)(H(2)O)(2)], contains one Zn(2+) ion located on a center of symmetry, two 3-[4-(1H-imidazol-1-yl)phen-yl]-5-(pyridin-2-yl)-1H-1,2,4-triazol-1-ide (Ippyt) ligands and two coordinating water mol-ecules. The Zn(II) ion is six-coordinated in a distorted octa-hedral coordination geometry by four N atoms from two Ippyt ligands and by two O atoms from two water mol-ecules. Adjacent units are inter-connected though O-H⋯N hydrogen bonds, forming a three-dimensional network.

12.
Artigo em Chinês | MEDLINE | ID: mdl-20137387

RESUMO

OBJECTIVE: To evaluate the influence of individual genetic polymorphisms of metabolic enzymes on urinary styrene metabolites. METHODS: 58 workers occupationally exposed to styrene were divided into the high exposure group (≥ 100 mg/m³) and the low exposure group (< 100 mg/m³). The microfluidic chip technology was used to determine the SNPs of CYP2B6, CYP2D6 and GSTP1 and the influence of gene polymorphisms on the metabolism of styrene was statistically analyzed. RESULTS: The level of urine styrene metabolites level was influenced by genotypes of CYP2B6, CYP2D6 and GSTP1 [(280.28 +/- 100.60) mg/g Cr vs (183.48 +/- 127.52) mg/g Cr, (233.04 +/- 77.56) mg/g Cr vs (152.46 +/- 95.47) mg/g Cr, (32.88 +/- 7.14) mg/g Cr vs (24.47 +/- 5.59) mg/g Cr, P < 0.05)]. The metabolism of CYP2B6 G/G homozygotic genotype to styrene was more active than G/T heterozygotic genotype and T/T mutation genotype. The level of PHEMA in GSTP1 homozygotic genotype subjects was significantly higher than that in the group of homozygotic genotype [(32.07 +/- 7.32) mg/g Cr vs (25.59 +/- 6.95) mg/g Cr, P < 0.05)]. The influence of CYP2D6 genotypes on urinary metabolites was also observed in the same study [(56.36 +/- 109.72) mg/g Cr vs (177.13 +/- 116.21) mg/g Cr, (118.73 +/- 84.55) mg/g Cr vs (148.48 +/- 99.83) mg/g Cr, (18.29 +/- 13.50) mg/g Cr vs (19.95 +/- 13.30) mg/g Cr, P < 0.05)]. CONCLUSION: Genotypes of CYP2B6, GSTP1 and CYP2D6 are related to susceptibility to the metabolism of styrene in human.


Assuntos
Hidrocarboneto de Aril Hidroxilases/genética , Citocromo P-450 CYP2D6/genética , Glutationa S-Transferase pi/genética , Oxirredutases N-Desmetilantes/genética , Estireno/farmacocinética , Estireno/urina , Adulto , Citocromo P-450 CYP2B6 , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Exposição Ocupacional/efeitos adversos , Polimorfismo Genético , Estireno/efeitos adversos , Adulto Jovem
13.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 1): m50, 2009 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-21579948

RESUMO

In the title complex, [Mn(C(28)H(18)N(2)O(2))(N(3))(H(2)O)], the Mn(III) ion adopts a distorted fac-MnO(3)N(3) octa-hedral geometry arising from the O,N,N',O'-tetra-dentate Schiff base ligand, an azide ion and a water mol-ecule. In the crystal, inter-molecular O-H⋯(O,O) and O-H⋯N hydrogen bonds and π-π inter-actions [centroid-centroid separation = 3.5535 (13) Å] link the mol-ecules into chains.

14.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 1): m11, 2008 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-21581476

RESUMO

In the title compound, [Ni(C(8)H(7)O(3))(C(10)H(8)N(2))]ClO(4), the Ni(II) atom is in a slightly distorted square-planar coordination by two N atoms from the 2,2'-bipyridine (bipy) ligand and two O atoms from the deprotonated 2-formyl-6-methoxy-phenolate (mbd) ligand. The bipy ligand is nearly coplanar with the Ni(II) square plane, the Ni atom being only 0.042 (2) Šfrom the mean plane, whereas the benzaldehyde plane is folded with respect to the square plane, making a dihedral angle of 19.17 (8)°. One of the O atoms of the perchlorate anion is involved in a weak inter-action with the Ni atom, with an Ni-O distance of 2.5732 (18) Å. The packing is stabilized by weak C-H⋯O inter-actions.

15.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 1): m42-3, 2008 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-21581515

RESUMO

In the title compound, [Ni(2)(SO(4))(2)(C(13)H(8)N(4))(2)(H(2)O)(4)]·2H(2)O, the complete dimeric complex is generated by an inversion center. The Ni(II) atoms are octa-hedrally coordinated by two N atoms from one 1H-imidazo[4,5-f][1,10]phenanthroline (IP) ligand and two O atoms from two adjacent sulfate ions forming the equatorial plane, with two coordinated water mol-ecules in the axial sites. Both of the sulfate ions act as bidentate-bridging ligands connecting the two Ni(II) ions, thus generating a binuclear complex. In the crystal structure, O-H⋯O and O-H⋯N hydrogen bonds involving the coordinated and uncoordinated water mol-ecules and N-H⋯O links lead to the formation of a two-dimensional sheet structure developing parallel to (010). Weak π-π stacking inter-actions [centroid-centroid separation = 3.613 (2) Å] between the IP ligands also occur.

16.
Chemistry ; 12(24): 6281-9, 2006 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-16739156

RESUMO

The synthesis and structures of six compounds prepared in two different systems have been explored with the purpose of isolating coordination polymers with interlaced triple-stranded molecular braid architectures. The dinuclear paddle-wheel units of [Cu(2)(maa)(4)2 H(2)O] can be rationally tuned to form three classes of isomorphous compounds, namely [Cu(2)(maa)(4)(bpp)] (1) (bpp=1,3-bis(4-pyridyl)propane, Hmaa=2-methylacrylic acid), [Cu(3)(maa)(6)(bpp)(2)] (2), and[Cu(4)(maa)(8)(bpp)(4)(H(2)O)(2)]2 H(2)O (3), with a bridging bpp ligand, at controlled ligand-to-metal molar ratios, and lead to three coordination polymers having similar one-dimensional characteristics but different mono- and dinuclear nodes. Compound 1, with a bpp:[Cu(2)(maa)(4)2 H(2)O] stoichiometry of 1:1, contains a zigzag chain containing dinuclear nodes, whereas polymer 2, with a bpp:[Cu(2)(maa)(4)2 H(2)O] stoichiometry of 1.5:1, also adopts the topology of a zigzag chain but with both mono- and dinuclear nodes. Compound 3, with a bpp:[Cu(2)(maa)(4)2 H(2)O] stoichiometry of 2:1, contains a neutral, interlaced, triple-stranded molecular braid, which is interwoven by three single-stranded meso-helical chains that contain only a mononuclear node. With the three aromatic chelating terminal ligands 2,2':6',2''-terpyridine (tpy), 1,10-phenanthroline (phen), and di(2-pyridyl)amine (dpa) we have also prepared three neutral complexes containing the linear, rigid bridging ligand biphenyl-4,4'-dicarboxylate (bpdc), namely [Cd(bpdc)(tpy)]H(2)O (4), [Cu(bpdc)(phen)(2)]4.25 H(2)O (5), and [Cu(bpdc)(dpa)] (6). An infinite meso-helix is formed initially in 4, and then three of these chains assemble into a triple-stranded braid similar to that of 3. Complexes 5 and 6 have a mononuclear and a looped dinuclear structure, respectively. Compounds 3 and 4 are unusual examples of triple-stranded molecular braid coordination frameworks based on different types of co-ligands.

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