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1.
Inorg Chem ; 62(23): 8784-8788, 2023 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-37253277

RESUMO

Herein we report the structural change and radical generation of a cadmium-based metal-organic framework (Cd-MOF) induced by external electric fields. Under a weaker single electric field, different coordination modes of Cd-L lead to 3D → 2D structural change. Under stronger superposed electric fields, Cd-MOF was excited to produce a stable free radical. This study will provide a new avenue for the controlled assembly of MOFs.

2.
Surg Endosc ; 36(6): 3994-4003, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34494149

RESUMO

PURPOSE: Identifying the lymphatic drainage pathway is important for accurate lymph node (LN) dissection in esophageal cancer (EC). This study aimed to assess lymphatic drainage mapping in thoracic EC using near-infrared fluorescent (NIRF) imaging with indocyanine green (ICG) and identify its feasibility for intraoperative LN drainage visualization and dissection. METHODS: From November 2019 to August 2020, esophagectomy was performed using intraoperative NIRF navigation with ICG injected into the esophageal submucosa by endoscopy. All LNs were divided into four groups according to the NIRF status and presence of metastasis: NIRF+LN+, NIRF+LN-, NIRF-LN+, and NIRF-LN-. RESULTS: Regional LNs were detected in all 84 enrolled patients with thoracic EC. A total of 2164 LNs were removed, and the mean number of dissected LNs was 25.68 ± 12.00. NIRF+ LNs were observed in all patients and distributed at 19 LN stations, which formed lymphatic drainage maps. The top five LN stations of NIRF+ probability in upper thoracic EC were No. 7, 106ecR, 107, 1, and 106recL; in middle thoracic EC, they were No. 107, 7, 110, 1, and 105; and in lower thoracic EC, they were No. 107, 7, 110, 106recR, and 1. There were no cases of ICG-related adverse events or chylothorax. The 30-day mortality rate was 0%. Major complications included anastomotic fistula (7.14%), pneumonia (4.76%), pleural effusion (13.10%), atelectasis (3.75%), hoarseness (8.33%), and arrhythmia (4.76%). CONCLUSION: Regional LN mapping of thoracic EC was performed using ICG/NIRF imaging, which showed different preferred LN drainage stations in various anatomical locations of the thoracic esophagus. ICG/NIRF imaging is feasible for intraoperative LN drainage visualization and dissection. CLINICAL TRIAL REGISTRATION: The clinical trial registration number is NCT04173676 ( http://www. CLINICALTRIALS: gov/ ).


Assuntos
Neoplasias Esofágicas , Imagem Óptica , Neoplasias Esofágicas/diagnóstico por imagem , Neoplasias Esofágicas/patologia , Neoplasias Esofágicas/cirurgia , Humanos , Verde de Indocianina , Excisão de Linfonodo/métodos , Linfonodos/patologia , Imagem Óptica/métodos
3.
Appl Microbiol Biotechnol ; 106(2): 743-754, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34982194

RESUMO

Nitrite-dependent anaerobic methane oxidation (n-damo) acts as a crucial link between biogeochemical carbon and nitrogen cycles. Nevertheless, very few studies have characterized n-damo microorganisms in high-latitude permafrost regions. Therefore, this study investigated the vertical distribution and diversity of n-damo bacterial communities in soil from three forest types in the permafrost regions of the Daxing'an Mountains. A total of 11 and 8 operational taxonomic units (OTUs) of n-damo 16S rRNA and pmoA genes were observed, respectively. Remarkable spatial variations in n-damo bacteria community richness, diversity, and structure were observed at different soil depths. Moreover, the abundances of n-damo bacteria (16S rRNA and pmoA genes) varied between 1.55 × 104 to 1.47 × 105 and 1.31 × 103 to 3.11 × 104 copies g-1 dry soil (ds), as demonstrated by quantitative PCR analyses. 13CH4 stable isotope tracer assays indicated that the potential n-damo rates varied from 0 to 1.26 nmol g-1 day-1, with the middle layers (20-40 cm and 40-60 cm) exhibiting significantly higher values than the upper (0-20 cm) and deeper layers (80-100 cm) in all three forest types. Redundancy analyses (RDA) indicated that total organic carbon (TOC), nitrate (NO3--N), and nitrite (NO2--N) were key modulators of the distribution of n-damo bacterial communities. This study thus demonstrated the widespread occurrence of n-damo bacteria in cold and high-latitude regions of forest ecosystems and provided important insights into the global distribution of these bacteria. KEY POINTS: • This study detected n-damo bacteria in soil samples obtained from the permafrost region of three forest types in the Daxing'an Mountains. • The community composition of n-damo bacteria was mainly affected by soil depth and not forest type. • The abundances of n-damo bacteria first increased and then decreased at higher soil depths.


Assuntos
Nitritos , Pergelissolo , Anaerobiose , Bactérias/genética , Ecossistema , Metano , Oxirredução , RNA Ribossômico 16S/genética
4.
Molecules ; 27(21)2022 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-36364436

RESUMO

Esophageal squamous cell carcinoma (ESCC) is one of the most lethal malignancies globally. Peptide-based tumor-targeted imaging is critical for ESCC imaging. In this study, we aim to identify a peptide-targeting IGF2BP2 that specifically binds to human ESCC for near-infrared imaging of esophageal cancer. Applying phage display techniques, we identified a peptide target for IGF2BP2 which was confirmed to be highly expressed in ESCC cell lines or tumor tissue and may serve as an imaging target for ESCC. We conjugated the peptide to the NIRF group, Cy5, and further evaluated the targeting efficacy of the probe at a cellular level and in animal tumor models. The Cy5 conjugated peptide (P12-Cy5) showed a high binding affinity to human ESCC cells in vitro. In vivo, optical imaging also validated the tumor-targeting ability of P12-Cy5 in KYSE-30-bearing subcutaneous ESCC tumor models. Furthermore, the results of biodistribution showed a significantly higher fluorescence intensity in tumors compared to scrambled peptide, which is consistent with in vivo observations. In summary, an IGF2BP2-targeted peptide was successfully identified. In vitro and in vivo experiments confirmed that P12-Cy5 has high affinity, specificity and tumor-targeting properties. Thus, P12-Cy5 is a prospective NIR probe for the imaging of ESCC.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Animais , Humanos , Carcinoma de Células Escamosas do Esôfago/diagnóstico por imagem , Neoplasias Esofágicas/metabolismo , Distribuição Tecidual , Estudos Prospectivos , Linhagem Celular Tumoral , Peptídeos/química , Proteínas de Ligação a RNA/metabolismo
5.
Inorg Chem ; 58(5): 2916-2920, 2019 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-30784270

RESUMO

Four [Ag-Ag]2+ unit-encapsulated trimetallic cages 1-4 were synthesized from one new tripodal ligand L and silver salts in different solvent systems by a one-pot method. The formation of coordination cages occurred simultaneously with the condensation of amino groups and ketone. The remarkable structural feature of cages 1-4 is their spontaneous incorporation of [Ag-Ag]2+ cationic units. Moreover, the argentophilic interactions are modulated by the uncoordinated amino substituents. The study herein shows that modification and subtle changes of the cage structures could be realized by a one-pot synthetic method.

6.
J Insect Sci ; 152015.
Artigo em Inglês | MEDLINE | ID: mdl-26175461

RESUMO

The effects of cycloxaprid (a modified neonicotinoid insecticide) and buprofezin (a thiadiazine insecticide) on mortality of the white-backed planthopper (WBPH), Sogatella furcifera, were determined in laboratory assays. Cycloxaprid killed WBPH nymphs and adults but buprofezin killed only nymphs, and cycloxaprid acted faster than buprofezin. One day after infestation, mortality of third-instar nymphs was >65% with cycloxaprid at 125 mg liter(-1) but was <38% with buprofezin at 148 mg liter(-1). By the 4th day after infestation, however, control of nymphs by the two insecticides was similar, and cycloxaprid at 125 mg liter(-1) caused ≥ 80% mortality of adults but buprofezin at 148 mg liter(-1) (the highest rate tested) caused almost no adult mortality. LC50 values for cycloxaprid were lowest with nymphs, intermediate with adult males, and highest with adult females. Although buprofezin was slower acting than cycloxaprid, its LC50 for nymphs 5 d after infestation was 3.79-fold lower than that of cycloxaprid. Mean carboxylesterase (CarE) specific activity of nymphal WBPH treated with cycloxaprid and buprofezin was higher than that of control, but there was no significant difference between cycloxaprid and control (no insecticide), and it was significantly higher for buprofezin than those of cycloxaprid and control. For glutathione S-transferase and mixed function oxygenase, the specific activity of nymphal WBPH treated with buprofezin was significantly higher than those of cycloxaprid and control, too.


Assuntos
Hemípteros/efeitos dos fármacos , Compostos Heterocíclicos com 3 Anéis/farmacologia , Inseticidas/farmacologia , Piridinas/farmacologia , Tiadiazinas/farmacologia , Animais , Feminino , Controle de Insetos , Dose Letal Mediana , Masculino , Ninfa/efeitos dos fármacos
7.
Acta Crystallogr C ; 69(Pt 6): 601-5, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23744376

RESUMO

Two new symmetric double-armed oxadiazole-bridged ligands, 4-methyl-{5-[5-methyl-2-(pyridin-3-ylcarbonyloxy)phenyl]-1,3,4-oxadiazol-2-yl}phenyl pyridine-3-carboxylate (L1) and 4-methyl-{5-[5-methyl-2-(pyridin-4-ylcarbonyloxy)phenyl]-1,3,4-oxadiazol-2-yl}phenyl pyridine-4-carboxylate (L2), were prepared by the reaction of 2,5-bis(2-hydroxy-5-methylphenyl)-1,3,4-oxadiazole with nicotinoyl chloride and isonicotinoyl chloride, respectively. Ligand L1 can be used as an organic clip to bind Cu(II) cations and generate a molecular complex, bis(4-methyl-{5-[5-methyl-2-(pyridin-3-ylcarbonyloxy)phenyl]-1,3,4-oxadiazol-2-yl}phenyl pyridine-3-carboxylate)bis(perchlorato)copper(II), [Cu(ClO4)2(C28H20N4O5)2], (I). In compound (I), the Cu(II) cation is located on an inversion centre and is hexacoordinated in a distorted octahedral geometry, with the pyridine N atoms of two L1 ligands in the equatorial positions and two weakly coordinating perchlorate counter-ions in the axial positions. The two arms of the L1 ligands bend inward and converge at the Cu(II) coordination point to give rise to a spirometallocycle. Ligand L2 binds Cu(I) cations to generate a supramolecule, diacetonitriledi-µ3-iodido-di-µ2-iodido-bis(4-methyl-{5-[5-methyl-2-(pyridin-4-ylcarbonyloxy)phenyl]-1,3,4-oxadiazol-2-yl}phenyl pyridine-4-carboxylate)tetracopper(I), [Cu4I4(CH3CN)2(C28H20N4O5)2], (II). The asymmetric unit of (II) indicates that it contains two Cu(I) atoms, one L2 ligand, one acetonitrile ligand and two iodide ligands. Both of the Cu(I) atoms are four-coordinated in an approximately tetrahedral environment. The molecule is centrosymmetric and the four I atoms and four Cu(I) atoms form a rope-ladder-type [Cu4I4] unit. Discrete units are linked into one-dimensional chains through π-π interactions.

8.
Transl Lung Cancer Res ; 12(6): 1256-1263, 2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37425401

RESUMO

Background: In recent years, osimertinib, a third-generation epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI), has been recommended as a first-line treatment for EGFR-mutant advanced non-small cell lung cancer (NSCLC). A phase III study (AENEAS) to assess the efficacy and safety of aumolertinib, another third-generation EGFR-TKI, vs. gefitinib as a first-line treatment in patients with locally advanced or metastatic NSCLC harboring EGFR mutations has also achieved positive results. Despite the improvements in progression-free survival (PFS) and overall survival (OS) of third- vs. first-generation EGFR-TKIs, combined treatment strategies to postpone drug resistance and further prolong survival benefits remain to be explored. Methods: We conducted a nonrandomized phase II trial (ChiCTR2000035140) of an oral multitarget antiangiogenic TKI (anlotinib) with third-generation EGFR-TKIs (osimertinib or aumolertinib) in untreated patients with EGFR mutation and advanced NSCLC. Anlotinib and the third-generation EGFR-TKIs were orally administrated (anlotinib at a dose of 12 mg once every other day and osimertinib at 80 mg once daily or aumolertinib at 110 mg once daily). The primary end point of the study was the objective response rate (ORR). Secondary endpoints included the disease control rate (DCR), OS, PFS, and safety of the combined treatment. Results: Enrollment was ceased due to treatment-related adverse events (trAEs) after 11 of 35 planned patients were treated. Among these 11 patients, two were lost to follow-up, and the treatment of five of the remaining nine patients was discontinued due to trAEs, including stomachache, rash, hyponatremia, pulmonary embolism, and interstitial pneumonia. AEs of grade 3 or worse were observed in five patients, but no treatment-related death occurred in these patients. Conclusions: Combining anlotinib and third-generation EGFR-TKIs in untreated EGFR-mutant patients with advanced NSCLC demonstrated significantly increased toxicity, suggesting that the combined treatment strategy was an inappropriate therapeutic choice in this setting.

9.
J Genet Genomics ; 50(5): 330-340, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36414223

RESUMO

Multiple primary lung cancer (MPLC) is an increasingly prevalent subtype of lung cancer. According to recent genomic studies, the different lesions of a single MPLC patient exhibit functional similarities that may reflect evolutionary convergence. We perform whole-exome sequencing for a unique cohort of MPLC patients with multiple samples from each lesion found. Using our own and other relevant public data, evolutionary tree reconstruction reveals that cancer driver gene mutations occurred at the early trunk, indicating evolutionary contingency rather than adaptive convergence. Additionally, tumors from the same MPLC patient are as genetically diverse as those from different patients, while within-tumor genetic heterogeneity is significantly lower. Furthermore, the aberrant molecular functions enriched in mutated genes for a sample show a strong overlap with other samples from the same tumor, but not with samples from other tumors or other patients. Overall, there is no evidence of adaptive convergence during the evolution of MPLC. Most importantly, the similar between-tumor diversity and between-patient diversity suggest that personalized therapies may not adequately account for the genetic diversity among different tumors in an MPLC patient. To fully exploit the strategic value of precision medicine, targeted therapies should be designed and delivered on a per-lesion basis.


Assuntos
Neoplasias Pulmonares , Neoplasias Primárias Múltiplas , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/terapia , Neoplasias Pulmonares/patologia , Neoplasias Primárias Múltiplas/genética , Neoplasias Primárias Múltiplas/patologia , Neoplasias Primárias Múltiplas/cirurgia , Mutação
10.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 5): m648-9, 2012 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-22590137

RESUMO

In the crystal of the title compound, [Cu(2)Cl(4)(C(50)H(32)N(9)O(8)P(3))(2)], the binuclear mol-ecule is located across an inversion center. Each Cu(2+) cation is coordinated by two pyridine N atoms from symmetry-related 4,4;6,6-bis-(biphenyl-2,2'-diyldi-oxy)-2,2-bis-{2-[5-(pyridin-4-yl)-1,3,4-oxadiazol-2-yl]phen-oxy}cyclo-triphosphazene (L) ligands, a pair of bridging Cl(-) anions and a terminal Cl(-) anion, forming a distorted CuCl(3)N(2) square-pyramidal geometry. Weak intra-molecular C-H⋯O and inter-molecular C-H⋯N inter-actions occur in the crystal.

11.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 6): m727-8, 2012 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-22719292

RESUMO

In the title compound, [Zn(4)(C(16)H(10)N(4)O(2))(4)]·4H(2)O, the N'-[(8-oxidoquinolin-7-yl)methyl-idene]isonicotinohydrazidate (L(2-)) ligand binds to the metal ions, forming stable five- and six-membered chelate rings, leaving the pyridyl groups free. The compound is a tetra-nuclear Zn(II) complex centered about a fourfold roto-inversion axis, with the ligand coordinating in the doubly deprotonated form. The Zn(II) atom has a distorted square-pyramidal geometry being coordinated by one N and two O-atom donors from the doubly deprotonated L(2-) ligand, and by one N atom and one O-atom donor from a symmetry-related L(2-) ligand. In the crystal, four symmetry-related lattice water mol-ecules, centred about a fourfold roto-inversion axis, form a cyclic tetra-mer through O-H⋯O hydrogen bonds. These tetra-mers connect to the complex mol-ecules through O-H⋯N hydrogen bonds, forming a chain propagating along [100]. Neighbouring mol-ecules are linked by π-π inter-actions [centroid-centroid distance = 3.660 (2) Å] involving the quinolidine rings.

12.
Interact Cardiovasc Thorac Surg ; 34(5): 799-807, 2022 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-35015846

RESUMO

OBJECTIVES: Uniportal video-assisted thoracoscopic surgery (UniVATS) is widely used as a minimally invasive thoracic operation. The goal of our study was to analyse the effect of long-term experience with the UniVATS lobectomy on the learning curve. METHODS: The learning curves were quantitatively evaluated by the unadjusted cumulative sum, and they were segmented using joinpoint linear regression analysis. The variables were compared between subgroups using trend analysis, and linear regression analysis was applied to correlate clinical characteristics at different stages of the learning curve with the duration of the operation. RESULTS: The learning curve for the UniVATS lobectomy can be divided into 3 phases of proficiency at ∼200-300 procedures, with a fourth phase as the number of procedures increases. The 1st-52nd, 52nd-156th, 156th-244th and 244th-538th procedures comprised the preliminary learning stage, preliminary proficiency stage, proficiency stage and advanced proficiency stage, respectively. Surgical outcomes and their variability between stages improved with increasing case numbers, with the most significant addition of an auxiliary operating port and conversions. In multivariable analysis, as stages progressed, influences other than surgical experience increased the operative time, with male and extensive pleural adhesions in the preliminary proficiency stage; male and incomplete pulmonary fissures in the proficiency stage; and male, extensive pleural adhesions and incomplete pulmonary fissures in the advanced proficiency stage. CONCLUSIONS: As the number of procedures increases, there may be 4 different proficiency stages in the UniVATS lobectomy learning curve. The surgeon enters the fourth stage at approximately the 244th procedure. Moreover, at stage 4, the perioperative indicators tend to stabilize, and influences other than surgical experience become more significant.


Assuntos
Curva de Aprendizado , Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/cirurgia , Masculino , Pneumonectomia/efeitos adversos , Pneumonectomia/métodos , Estudos Retrospectivos , Cirurgia Torácica Vídeoassistida/efeitos adversos , Cirurgia Torácica Vídeoassistida/métodos
13.
J Cardiothorac Surg ; 17(1): 278, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36320014

RESUMO

BACKGROUND: Synchronous multiple primary lung cancers associated with small non-dominant nodules are commonly encountered. However, the incidence, follow-up, and treatment of small non-dominant tumors have been but little studied. We explored the prevalence and management of small non-dominant tumors and factors associated with interval growth. METHODS: This observational, consecutive, retrospective single-center study enrolled patients diagnosed with synchronous multiple primary lung cancers and small non-dominant tumors (≤ 6 mm in diameter) who underwent resection of the dominant tumor. The incidence, follow-up, and management of small non-dominant tumors and predictors of nodule growth were analyzed. RESULTS: There were 88 patients (12% of all lung cancer patients) with pathological diagnoses of synchronous multiple primary lung cancers. A total of 131 (18%) patients were clinically diagnosed with at least one small (≤ 6 mm in diameter) multiple primary lung cancer non-dominant tumor. 94 patients with 125 small-nodule non-dominant tumors clinically diagnosed as multiple primary lung cancers were followed-up for at least 6 months. A total of 29 (29/125, 23.2%) evidenced small pulmonary nodules (≤ 6 mm in diameter) that exhibited interval growth on follow-up computed tomography (CT). On multivariate analysis, a part-solid nodule (compared to a pGGN) (OR 1.23; 95% CI 1.08-1.40) or a solid nodule (compared to a pGGN) (OR 3.50; 95% CI 1.94-6.30) predicted small nodule interval growth. CONCLUSION: We found a relatively high incidence of multiple primary lung cancers with small non-dominant tumors exhibiting interval growth on follow-up CT, suggesting that resection of non-dominant tumors at the time of dominant tumor resection, especially when the nodules are part-solid or solid, is the optimal treatment.


Assuntos
Neoplasias Pulmonares , Nódulos Pulmonares Múltiplos , Neoplasias Primárias Múltiplas , Nódulo Pulmonar Solitário , Humanos , Prevalência , Estudos Retrospectivos , Nódulos Pulmonares Múltiplos/patologia , Neoplasias Pulmonares/patologia , Nódulo Pulmonar Solitário/patologia
14.
J Cardiothorac Surg ; 16(1): 288, 2021 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-34627298

RESUMO

BACKGROUND AND PURPOSE: We previously developed a new surgical method, namely, single-port inflatable mediastinoscopy simultaneous laparoscopic-assisted radical esophagectomy. The purpose of this study was to evaluate the effect of carbon dioxide inflation on respiration and circulation using this approach. METHODS: From April 2018 to October 2020, 105 patients underwent this novel surgical approach. The changes in respiratory and circulatory functions were reported when the mediastinal pressure and pneumoperitoneum pressure were 10 and 12 mmHg, respectively. Data on blood loss, operative time, and postoperative complications were also collected. RESULTS: 104 patients completed the operation successfully, except for 1 patient who was converted to thoracotomy because of intraoperative injury. During the operation, respectively, the heart rate, mean arterial pressure, central venous pressure, peak airway pressure, end-expiratory partial pressure of carbon dioxide and partial pressure of carbon dioxide increased in an admissibility range. The pH and oxygenation index decreased 1 h after inflation, but these values were all within a safe and acceptable range and restored to the baseline level after CO2 elimination. Postoperative complications included anastomotic fistula (8.6%), pleural effusion that needed to be treated (8.6%), chylothorax (0.9%), pneumonia (7.6%), arrhythmia (3.8%) and postoperative hoarseness (18.2%). There were no cases of perioperative death. CONCLUSIONS: When the inflation pressure in the mediastinum and abdomen was 10 mmHg and 12 mmHg, respectively, the inflation of carbon dioxide from single-port inflatable mediastinoscopy simultaneous laparoscopic-assisted radical esophagectomy did not cause serious changes in respiratory and circulatory function or increase perioperative complications.


Assuntos
Neoplasias Esofágicas , Laparoscopia , Neoplasias Esofágicas/cirurgia , Esofagectomia , Humanos , Mediastinoscopia , Respiração
15.
Chem Commun (Camb) ; 57(98): 13325-13328, 2021 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-34816267

RESUMO

The selective adsorption of APPT-Cd-MOF 1 for propyne, 2-butyne and phenylacetylene was confirmed by single-crystal analysis. In addition, the selective adsorption performance of Cd-MOF for C3H4/C3H6/C3H8 was investigated. The matching of the functionality and size/shape between porous materials and guest molecules clarified the specific recognition of 1 for linear alkyne molecules.

16.
Front Microbiol ; 12: 802213, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35003032

RESUMO

As a buffer layer for the energy and water exchange between atmosphere and permafrost, the active layer is sensitive to climate warming. Changes in the thermal state in active layer can alter soil organic carbon (SOC) dynamics. It is critical to identify the response of soil microbial communities to warming to better predict the regional carbon cycle under the background of global warming. Here, the active layer soils collected from a wetland-forest ecotone in the continuous permafrost region of Northeastern China were incubated at 5 and 15°C for 45 days. High-throughput sequencing of the 16S rRNA gene was used to examine the response of bacterial community structure to experimental warming. A total of 4148 OTUs were identified, which followed the order 15°C > 5°C > pre-incubated. Incubation temperature, soil layer and their interaction have significant effects on bacterial alpha diversity (Chao index). Bacterial communities under different temperature were clearly distinguished. Chloroflexi, Actinobacteria, Proteobacteria, and Acidobacteria accounted for more than 80% of the community abundance at the phylum level. Warming decreased the relative abundance of Chloroflexi and Acidobacteria, while Actinobacteria and Proteobacteria exhibited increasing trend. At family level, the abundance of norank_o__norank_c__AD3 and Ktedonobacteraceae decreased significantly with the increase of temperature, while Micrococcaccac increased. In addition, the amount of SOC mineralization were positively correlated with the relative abundances of most bacterial phyla and SOC content. SOC content was positively correlated with the relative abundance of most bacterial phyla. Results indicate that the SOC content was the primary explanatory variable and driver of microbial regulation for SOC mineralization. Our results provide a new perspective for understanding the microbial mechanisms that accelerates SOC decomposition under warming conditions in the forest-wetland ecotone of permafrost region.

17.
Saudi J Biol Sci ; 28(12): 7037-7045, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34867005

RESUMO

In permafrost peatlands, the degradation of permafrost soil can raise soil temperature and alter moisture conditions, which increases the rate of loss of soil organic carbon (SOC). Here we selected three typical permafrost types that have very different active layer thicknesses but with soil originating from the same vegetation and which exist under comparable climatic conditions in the Da Xing'an mountain range: continuous permafrost, island permafrost, and island melting permafrost. To quantify the relative importance of control elements on SOC stabilization in these different permafrost types, we used correlation analysis to assess the relationship between organic carbon, physical and chemical properties and microorganisms, and explored the contribution of these factors to the accumulation of organic carbon. This study shows that the interaction between clay or silt, iron oxides and microorganisms have an important influence on the stability of organic carbon in permafrost peatlands.

18.
iScience ; 24(9): 103002, 2021 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-34505012

RESUMO

Urbanization is a pressing challenge for earth's humans because it is changing not only natural environments but also agricultural lands. Yet, the consequences of cropland loss on pest insect populations that largely depend on these habitats remain largely unclear. We used a 17-year data set to investigate the dynamics of three moth pest species (i.e., striped stem borer, yellow stem borer, and pink stem borer) and their driving forces across the largest mega-urban region of China. Total abundance of three pest species is declined by about 80%, which was strongly associated with cropland loss during rapid urbanization. Our findings indicate that not only the increasing conversion of natural areas to human-dominated landscapes but also that of agricultural lands to urban landscapes can be critical to insect populations. It is therefore essential to monitor and understand the insect dynamics in rapidly urbanizing regions, which are currently found in many developing countries worldwide.

19.
Inorg Chem ; 49(23): 11164-73, 2010 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-20973558

RESUMO

A new CdL(2)-MOF was synthesized based on an asymmetric Schiff-base ligand LH, which is obtained by condensation of 5-formyl-8-hydroxyquinoline and 3-pyridinecarboxylic acid hydrazide. A series of organic six-membered ring analogues, namely, 1,4-dioxane, cyclohexane, cyclohexene, benzene, cyclohexanone, and cyclohexanol, can be absorbed by the CdL(2) porous framework in liquid-phase to generate G(n)⊂CdL(2) (n = 1 and 2) host-guest complexes. In addition, the CdL(2) host framework displays different affinity for these six-membered ring substrates and can effectively separate them under mild conditions (i.e., 1, 4-dioxane > cyclohexane > cyclohexene and benzene > cyclohexanone > cyclohexanol). The empty CdL(2) displays strong green-yellow emission. Furthermore, these host-guest systems show an interesting guest-driven luminescent emission, and the emission intensities of these guest-loaded complexes are effectively reduced.


Assuntos
Benzeno/isolamento & purificação , Compostos de Cádmio/química , Cicloexanos/isolamento & purificação , Cicloexanóis/isolamento & purificação , Dioxanos/isolamento & purificação , Compostos Organometálicos/química , Adsorção , Compostos de Cádmio/síntese química , Cicloexanonas/isolamento & purificação , Modelos Moleculares , Compostos Organometálicos/síntese química , Bases de Schiff/síntese química , Bases de Schiff/química
20.
Acta Crystallogr C ; 66(Pt 6): m149-51, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20522936

RESUMO

The title novel two-dimensional coordination polymer, {[Zn(2)(C(10)H(8)N(3)O(2))(4)].H(2)O}(n), features a {Zn(2)L(2)} bimetallic ring repeat unit {L is the 3-[(1H-1,2,4-triazol-1-yl)methyl]benzoate ligand}. Each Zn(II) cation of the bimetallic ring is further bonded to two other L ligands, resulting in a novel infinite two-dimensional network structure with two channels of different sizes. The crystallographically unique Zn(II) atom is thus six-coordinated in a distorted octahedral environment of four carboxylate O atoms and two triazole N atoms. Two of these networks interpenetrate in an orthogonal arrangement to form the full three-dimensional framework, with disordered water molecules located in the channels.

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