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1.
Chemphyschem ; : e202300816, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38563655

RESUMO

The introduction of transition-metal doping has engendered a remarkable array of unprecedented boron motifs characterized by distinctive geometries and bonding, particularly those heretofore unobserved in pure boron clusters. In this study, we present a perfect (no defects) boron framework manifesting an inherently high-symmetry, bowl-like architecture, denoted as MB16- (M = Sc, Y, La). In MB16-, the B16 is coordinated to M atoms along the C5v-symmetry axis. The bowl-shaped MB16- structure is predicted to be the lowest-energy structure with superior stability, owing to its concentric (2π+10π) dual π aromaticity. Notably, the C5v-symmetry bowl-like B16- is profoundly stabilized through the doping of an M atom, facilitated by strong d-pπ interactions between M and boron motifs, in conjunction with additional electrostatic stabilization by an electron transfer from M to the boron motifs. This concerted interplay of covalent and electrostatic interactions between M and bowl-like B16 renders MB16- a species of exceptional thermodynamic stability, thus making it a viable candidate for gas-phase experimental detection.

2.
Chemistry ; : e202400714, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38622057

RESUMO

Quantum chemical calculations using ab initio methods at the MRCI+Q(8,9)/def2-QZVPPD and CCSD(T)/def2-QZVPPD levels as well as density functional theory are reported for the diatomic molecules AeN- (Ae = Ca, Sr, Ba). The nature of the bonds is analyzed with a variety of methods. The anions CaN- and SrN- have electronic triplet (3Π) ground states with nearly identical bond dissociation energies De ~57 kcal/mol calculated at the MRCI+Q(8,9)/def2-QZVPPD level of theory. In contrast, the heavier homologue BaN- has a singlet (1Σ+) ground state, which is only 1.1 kcal/mol below the triplet (3Σ-) state. The computed bond dissociation energy of (1Σ+) BaN- is 68.4 kcal/mol. The calculations at the CCSD(T)-full/def2-QZVPPD and BP86-D3(BJ)/def2-QZVPPD levels of theory are in reasonable agreement with the MRCI+Q(8,9)/def2-QZVPPD data except for the singlet (1Σ+) state, which has a large multireference character. The calculated atomic partial charges given by the CM5, Voronoi and Hirshfeld methods suggest small to medium-sized charge donation toward Ae atom Ae←N- for most electronic states. In contrast, the NBO method predicts for all species medium to large electronic charge donation toward nitrogen Ae→N-, which is due to the neglect of the (n)p AOs of Ae atoms as genuine valence orbitals.

3.
Inorg Chem ; 63(1): 653-660, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38146259

RESUMO

Quantum chemical calculations are carried out to design highly symmetric-doped boron clusters by employing the transition metal behavior of heavier alkaline earth (Ae = Ca, Sr, and Ba) metals. Following an electron counting rule, a set of monocyclic and tubular boron clusters capped by two heavier Ae metals were tested, which leads to the highly symmetric Ae2B8, Ae2B18, and Ae2B30 clusters as true minima on the potential energy surface having a monocyclic ring, two-ring tubular, and three-ring tubular boron motifs, respectively. Then, a thorough global minimum (GM) structural search reveals that a monocyclic B8 ring capped with two Ae atoms is indeed a GM for Ca2B8 and Ba2B8, while for Sr2B8 it is a low-lying isomer. Similarly, the present search also unambiguously shows the most stable isomers of Ae2B18 and Ae2B30 to be highly symmetric two- and three-ring tubular boron motifs, respectively, capped with two Ae atoms on each side of the tube. In these Ae-doped boron clusters, in addition to the electrostatic interactions, a substantial covalent interaction, specifically the bonding occurring between (n - 1)d orbitals of Ae and delocalized orbitals of boron motifs, provides the essential driving force behind their highly symmetrical structures and overall stability.

4.
Phys Chem Chem Phys ; 25(36): 24853-24861, 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37672278

RESUMO

C2 has attracted considerable attention from the scientific community for its debatable bonding situation. Herein, we show that the global minima of M2B2 and M3B2+ (M = Li, Na) possess similar covalent bonding patterns to C2. Because of strong charge transfer from M2/M3 to B2 dimer, they can be better described as [M2]2+[B2]2- and [M3]3+[B2]2- salt complexes with the B22- core surrounded perpendicularly by two and three M+ atoms, respectively. The energy decomposition analyses in combination with the natural orbital for chemical valence theory give four bonding components in C2, M2B2, and M3B2+ clusters. However, the fourth component does not arise from a bonding interaction but from polarization/hybridization. Considering the effect of Pauli repulsion in σ-space, the attractive covalent interaction in these molecules mainly comes from the two π-bonds. We further presented stable N-heterocyclic carbene (NHC) and triphenylphosphine (PPh3) ligands bound Li2B2(NHC)2 and Li2B2(PPh3)2 complexes. A comparative study of reactivity towards L = CO2, CO, and N2 between Li2B2(NHC)2 and B2(NHC)2 is also performed. L-Li2B2(NHC)2 is highly stable against L dissociation at room temperature for L = CO2 and CO, and the stability is markedly higher than that in L-B2(NHC)2. The larger B2→L π-backdonation in L-Li2B2(NHC)2 also makes L more activated than in L-B2(NHC)2.

5.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 30(6): 1752-1756, 2022 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-36476899

RESUMO

OBJECTIVE: To observe the evaluation value of characteristics of bone marrow cell morphology and immunophenotype in patients with non-Hodgkin lymphoma (NHL) leukemia on the bone marrow invasion of NHL. METHODS: The clinical data of 104 patients with NHL treated in the hospital from March 2016 to March 2021 were retrospectively analyzed, the characteristics of bone marrow smear morphology were recorded, and the analysis of bone marrow immunophenotype was performed, the evaluation value of bone marrow cell morphology and immunophenotype on NHL bone marrow invasion was analyzed. RESULTS: One hundred and four patients with NHL leukemia were found to have increased lymphoma cells by examination of bone marrow cell morphology, including 57 cases of B-cell type, 39 cases of T-cell type and 8 cases of NK/T cell type. The characteristics of bone marrow cell morphology were as follows: the cell body was large, irregular or round like in shape, the cytoplasm was much and mostly stained blue, a few cells could see a few granules, the nucleus was round or round like, some were twisted, the chromatin was thick and nucleolus was different, of which the T-cell type lymphoma cells had strong heteromorphism and more obvious nucleolus. B-cell type mainly expressed CD19, HLA-DR and CD20, and the positive rate was ≥70%. T-cell type mainly expressed CD7, HLA-DR and CD38, and the positive rate was ≥40%. NK/T cell types mainly expressed CD56 and CD161, and the positive rates was ≥50%. Compared the proportion of lymphoma cells between bone marrow smear and immunophenotype examination, there was no statistical significant difference (P>0.05). CONCLUSION: The characteristics of bone marrow cell morphology and immunophenotype have certain application value in the evaluation of bone marrow invasion in patients with NHL leukemia, both can complement each other and provide a feasible mean for the effective evaluation of bone marrow invasion in patients with NHL leukemia.


Assuntos
Leucemia , Linfoma não Hodgkin , Linfoma , Humanos , Medula Óssea , Estudos Retrospectivos , Células da Medula Óssea , Antígenos HLA-DR
6.
Sci Rep ; 11(1): 4918, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33649362

RESUMO

Denitrification is an important part of the nitrogen cycle and the key step to removal of nitrogen in surface-flow wetlands. In this study, we explored space-time analysis with high-throughput sequencing to elucidate the relationships between denitrifying bacteria community structures and environmental factors during different seasons. Our results showed that along the flow direction of different processing units, there were dynamic changes in physical and chemical indicators. The bacterial abundance indexes (ACEs) in May, August, and October were 686.8, 686.8, and 996.2, respectively, whereas the Shannon-Weiner indexes were 3.718, 4.303, and 4.432, respectively. Along the flow direction, the denitrifying bacterial abundance initially increased and then decreased subsequently during the same months, although diversity tended to increase. The abundance showed similar changes during the different months. Surface flow wetlands mainly contained the following denitrifying bacteria genus: unclassified Bacteria (37.12%), unclassified Proteobacteria (18.16%), Dechloromonas (16.21%), unranked environmental samples (12.51%), unclassified Betaproteobacteria (9.73%), unclassified Rhodocyclaceae (2.14%), and Rhodanobacter (1.51%). During different seasons, the same unit showed alternating changes, and during the same season, bacterial community structures were influenced by the second genus proportion in different processing units. ACEs were strongly correlated with temperature, dissolved oxygen, and pH. Bacterial diversity was strongly correlated with temperature, electrical conductivity, pH, and oxidation reduction potential. Denitrifying bacteria are greatly affected by environmental factors such as temperature and pH.

8.
World J Diabetes ; 11(9): 374-390, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32994866

RESUMO

BACKGROUND: Long noncoding RNAs (lncRNAs) and mRNAs are widely involved in various physiological and pathological processes. The use of glucagon-like peptide-1 receptor agonists (GLP-1RAs) is a novel therapeutic strategy that could promote insulin secretion and decrease the rate of ß-cell apoptosis in type 2 diabetes mellitus (T2DM) patients. However, the specific lncRNAs and mRNAs and their functions in these processes have not been fully identified and elucidated. AIM: To identify the lncRNAs and mRNAs that are involved in the protective effect of GLP-1RA in ß cells, and their roles. METHODS: Rat gene microarray was used to screen differentially expressed (DE) lncRNAs and mRNAs in ß cells treated with geniposide, a GLP-1RA. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were performed to assess the underlying functions of DE mRNAs. Hub mRNAs were filtered using the STRING database and the Cytoscape plugin, CytoHubba. In order to reveal the regulatory relationship between lncRNAs and hub mRNAs, their co-expression network was constructed based on the Pearson coefficient of DE lncRNAs and mRNAs, and competing endogenous RNA (ceRNA) mechanism was explored through miRanda and TargetScan databases. RESULTS: We identified 308 DE lncRNAs and 128 DE mRNAs with a fold change filter of ≥ 1.5 and P value < 0.05. GO and KEGG pathway enrichment analyses indicated that the most enriched terms were G-protein coupled receptor signaling pathway, inflammatory response, calcium signaling pathway, positive regulation of cell proliferation, and ERK1 and ERK2 cascade. Pomc, Htr2a, and Agtr1a were screened as hub mRNAs using the STRING database and the Cytoscape plugin, CytoHubba. This result was further verified using SwissTargetPrediction tool. Through the co-expression network and competing endogenous (ceRNA) mechanism, we identified seven lncRNAs (NONRATT027738, NONRATT027888, NONRATT030038, etc.) co-expressed with the three hub mRNAs (Pomc, Htr2a, and Agtr1a) based on the Pearson coefficient of the expression levels. These lncRNAs regulated hub mRNA functions by competing with six miRNAs (rno-miR-5132-3p, rno-miR-344g, rno-miR-3075, etc.) via the ceRNA mechanism. Further analysis indicated that lncRNA NONRATT027738 interacts with all the three hub mRNAs, suggesting that it is at a core position within the ceRNA network. CONCLUSION: We have identified key lncRNAs and mRNAs, and highlighted here how they interact through the ceRNA mechanism to mediate the protective effect of GLP-1RA in ß cells.

9.
Ecol Evol ; 9(15): 8714-8723, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31410274

RESUMO

Examining the coordination of leaf and fine root traits not only aids a better understanding of plant ecological strategies from a whole-plant perspective, but also helps improve the prediction of belowground properties from aboveground traits. The relationships between leaf and fine root traits have been extensively explored at global and regional scales, but remain unclear at local scales. Here, we measured six pairs of analogous leaf and fine root traits related to resource economy and organ size for coexisting dominant and subordinate vascular plants at three successional stages of temperate forest swamps in Lingfeng National Nature Reserve in the Greater Hinggan Mountains, NE China. Leaf and fine root traits related to resource acquisition (e.g., specific leaf area [SLA], leaf N, leaf P, root water content, and root P) decreased with succession. Overall, we found strong linear relationships between leaf dry matter content (LDMC) and root water content, and between leaf and root C, N, and P concentrations, but only weak correlations were observed between leaf area and root diameter, and between SLA and specific root length (SRL). The strong relationships between LDMC and root water content and between leaf and root C, N, and P held at the early and late stages, but disappeared at the middle stage. Besides, C and P of leaves were significantly correlated with those of roots for woody plants, while strong linkages existed between LDMC and root water content and between leaf N and root N for herbaceous species. These results provided evidence for the existence of strong coordination between leaf and root traits at the local scale. Meanwhile, the leaf-root trait relationships could be modulated by successional stage and growth form, indicating the complexity of coordination of aboveground and belowground traits at the local scale.

10.
Sci Total Environ ; 650(Pt 1): 1419-1425, 2019 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-30308829

RESUMO

Microorganisms play crucial roles in the nitrogen removal processes of wetlands. However, the key functional genes and microbes related to the nitrogen removal remain largely unknown in the free water surface constructed wetland (FWS CW). Here we studied the abundances of denitrifiers by targeting the key functional genes (nirS, nirK and nosZ) and investigated the community compositions of denitrifiers and their correlations with the abiotic variables in a FWS CW. The increase of nosZ/(nirS + nirK) and nirS/nirK ratios in the outlet indicated a shift of denitrifiers' communities which tended to release less nitrous oxide at the genetic potential level. The denitrifiers dominated the bacterial community which also remarkably changed from the inlet to the outlet. PICRUSt analysis revealed that the denitrifiers contributed to 39.1% of the nitrogen metabolism, 38.9% of the amino acid metabolism and 25.6% of the amino acid related enzymes. Four bacterial genera including Hydrogenophaga, Hylemonella, Aquabacterium and Cellvibrio were detected as the putative keystone denitrifiers. The abundance (nirS, nirK and nosZ) and the relative abundance of putative keystone denitrifiers were significantly correlated with total organic carbon, oxidation-reduction potential and C/N ratio, which could be regarded as the determinants for the denitrification process in the free water.

11.
Front Pharmacol ; 9: 1077, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30319414

RESUMO

Arctium lappa (burdock) is the most popular daily edible vegetable in China and Japan because of its general health tonic effects. Previous studies focused on the beneficial role of Arctigenin but neglected its potential side-effects and toxicities. In the present study, the sub-chronic toxicity profile of Arctigenin following 28 days of consecutive exposure was investigated in rats. The results showed that during the drug exposure period, Arctigenin-12 mg/kg administration resulted in focal necrosis and lymphocytes infiltration of heart ventricular septal muscle cells. In the kidney cortical zone, the renal tubular epithelial cells were swollen, mineralized, and lymphocyte infiltrated. In the liver, the partial hepatocyte cytoplasm showed vacuolation and fatty changes, focal necrosis, and interstitial lymphocyte infiltration. In the rats that underwent 36 mg/kg/day administration, there was bilateral testis and epididymis atrophy. In the lung and primary bronchus, erythrocytes and edema fluid were observed. Changes of proestrus or estrus were observed in the uterus, cervix, and vagina intimal epithelial cells. Lymphocytic focal infiltration occurred in the prostate mesenchyme. The high dosage of Arctigenin only decreased the body weight at day 4. At the end of the recovery period, histopathological changes were irreversible, even after withdrawal of the drug for 28 days. Focal necrosis still existed in the heart ventricular septal muscle cells and hepatocytes. Lymphocyte infiltrations were observed in the heart, renal cortex, hepatocyte, and pancreas exocrine gland. Meanwhile, atrophy occurred in the testicles and pancreas. In addition, in the Arctigenin-12 mg/kg group, creatinine (CREA) and brain weight were both significantly increased. The toxicokinetical study demonstrated that Arctigenin accumulated in the organs of rats. The food consumption, hematological, and biochemical parameters were not associated with the above results. These contradictory results might result from the lesions induced by Arctigenin, which were not sufficiently serious to change the parameters. These results suggest that Arctium lappa should be consumed daily with caution because of the potential toxicity induced by Arctigenin. According to all results, the lowest observed adverse effect level (LOAEL) was induced by 12 mg/kg daily exposure to Arctigenin, and the No-observed-adverse-effect-level (NOAEL) should be lower than 12 mg/kg.

12.
Huan Jing Ke Xue ; 39(1): 415-421, 2018 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-29965709

RESUMO

At the Jiapigou gold mine of the Songhua River upstream, reed leaves (Phragmites australis), soil, and water samples were collected from June (summer) and September (autumn) 2016 for the determination of mercury. Moreover, the mercury concentrations in the air were determined synchronously. Furthermore, the level of mercury pollution in the reed leaves was determined by a single factor pollution index method, and the relationships among mercury concentrations in the reed leaves and environmental factors were analyzed to research the distribution characteristics, influencing factors, and correlations around the gold mining area. The results show that, in terms of spatial distribution, the mercury concentrations in reed leaves, soil, and water gradually decay with the distance from the gold mining area, and the spatial distribution of the mercury concentrations in the air was not obvious. Regarding a temporal distribution, the mercury concentrations in the reed leaves in summer were lower than those in autumn in the heavy pollution areas, while the distribution in the light pollution areas was the opposite, as the mercury concentrations of air and soil in summer were higher than those in autumn. The influence of environmental factors on the mercury concentrations in the reed leaves was soil > air > water. In addition, after stopping gold mining and processing using mercury, the mercury source in the area was the soil.


Assuntos
Mercúrio/análise , Mineração , Poaceae/química , Poluentes do Solo/análise , China , Monitoramento Ambiental , Ouro , Folhas de Planta/química , Rios , Estações do Ano , Solo
13.
Microb Ecol ; 74(4): 877-887, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28492987

RESUMO

Increasing efforts have been devoted to exploring the impact of environmental stresses on soil bacterial communities, but the work on the archaeal community is seldom. Here, we constructed microcosm experiments to investigate the responses of archaeal communities to the subsequent dry-rewetting (DW) disturbance in two contrasting soils (fluvo-aquic and red soil) after 6 years of copper pollution. Ten DW cycles were exerted on the two soils with different copper levels, followed by a 6-week recovery period. In both soils, archaeal diversity (Shannon index) in the high copper-level treatments increased over the incubation period, and archaeal community structure changed remarkably as revealed by the non-metric multidimensional scaling ordinations. In both soils, copper pollution altered the response of dominant operational taxonomic units (OTUs) to the DW disturbance. Throughout the incubation and recovery period, the resistance of archaeal abundance to the DW disturbance was higher in the copper-polluted soils than soils without pollution. Taken together, copper pollution altered the response of soil archaeal diversity and community composition to the DW disturbance and increased the resistance of the archaeal abundance. These findings have important implications for understanding soil microbial responses to ongoing environmental change.


Assuntos
Archaea/fisiologia , Cobre/análise , Microbiologia do Solo , Poluentes do Solo/análise , Água/análise , Archaea/efeitos dos fármacos , China , Sequenciamento de Nucleotídeos em Larga Escala , Microbiota/efeitos dos fármacos , Microbiota/fisiologia , Reação em Cadeia da Polimerase , Solo/química
14.
Front Plant Sci ; 8: 2253, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29379514

RESUMO

Hydrological conditions determine the distribution of plant species in wetlands, where conditions such as water depth and hydrological fluctuations are expected to affect the interspecific interactions among emergent wetland species. To test such effects, we conducted a greenhouse experiment with three treatment categories, interspecific interaction (mixed culture or monoculture), water depth (10 or 30 cm depth), and hydrological fluctuation (static or fluctuating water level), and two common emergent wetland plant species, Scirpus planiculumis Fr. (Cyperaceae) and Phragmites australis var. baiyangdiansis (Gramineae). An increase in the water depth significantly restrained the growth of both S. planiculumis and P. australis, while hydrological fluctuations did not obviously alter the growth of either species. In addition, both water depth and hydrological fluctuations significantly affected the interspecific interaction between these two wetland species. P. australis benefited from interspecific interaction under increasing water depth and hydrological fluctuations, and the RII values were clearly positive for plants grown at a water depth that fluctuated around 30 cm. The results may have some implications for understanding how S. planiculumis and P. australis, as well as wetland communities, respond to the natural variation or human modification of hydrological conditions.

15.
Sci Rep ; 6: 36486, 2016 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-27819344

RESUMO

SL4, a chalcone-based compound, has been shown to retard tumor invasion and angiogenesis by suppressing HIF1 activity and to induce apoptosis by promoting ROS release. Here, we report that SL4 is able to inhibit the proliferation of different types of breast cancer cell in vitro and in vivo by inducing G2/M cell cycle arrest. Our results showed that SL4 exhibited strong anti-proliferative activity in several human breast cancer cell lines, with IC50 values lower than 1.3 µM. Further studies indicated that SL4 induced G2/M arrest in these cell lines. Mechanistically, SL4 reduces the expression of cyclin A2 and cdc25C and decreases the activity of the cdc2/cyclin B1 complex. Notably, SL4 treatment resulted in an obvious increase in p21 mRNA and protein levels through activation of MAPK signaling pathways, but not the TGF-ß pathway. SP600125 and PD98059, specific inhibitors of JNK kinase and ERK kinase, significantly blocked the SL4-induced G2/M phase arrest and upregulation of p21. Furthermore, SL4 suppressed the growth of established breast tumors in nude mice through upregulation of p21 and downregulation of cdc25C, and displayed a good safety profile. Taken together, these findings demonstrate the potential value of SL4 as a novel multi-target anti-tumor drug candidate.


Assuntos
Antineoplásicos/farmacologia , Chalconas/farmacologia , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Pontos de Checagem da Fase M do Ciclo Celular/efeitos dos fármacos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Transdução de Sinais/efeitos dos fármacos , Animais , Antineoplásicos/química , Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Proteína Quinase CDC2/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Chalconas/química , Chalconas/uso terapêutico , Inibidor de Quinase Dependente de Ciclina p21/genética , Regulação para Baixo/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Feminino , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Células MCF-7 , Camundongos , Camundongos SCID , Espécies Reativas de Oxigênio/metabolismo , Fator de Crescimento Transformador beta/metabolismo
16.
Huan Jing Ke Xue ; 37(5): 1754-62, 2016 May 15.
Artigo em Chinês | MEDLINE | ID: mdl-27506028

RESUMO

Investigation on the concentrations and the distribution characteristics of total mercury in atmosphere, water surface and soil/ sediments of Hengshuihu wetland was carried out based on a uniform set point sampling method. The geoaccumulation index and potential ecological risk index methods were simultaneously used to assess the mercury pollution in Hengshuihu wetland ecosystem. The results showed that: the total mercury content in Hengshuihu wetland atmosphere ranged from 1.0 to 5.0 ng · m⁻³, with an average of (2.9 ± 0.85) ng · m⁻³; the total mercury content in water surface ranged from 0.010 to 0.57 µg · L⁻¹, with the average value of (0.081 ± 0.053) µg · L⁻¹; the total mercury content in soil/sediment ranged from 0.001 0 to 0.058 mg · kg⁻¹, with an average of (0.027 ± 0.013) mg · kg⁻¹. The distribution features of total mercury in Hengshuihu wetland were as follows: the total mercury concentration in surface water of the shore was significantly higher than that in the center (P < 0.05), but the total mercury concentration of sediments in the center of the lake was significantly higher than that at the shore (P < 0.05); the total mercury in the soil of shore had a consistent trend with that in the atmosphere; high concentrations of total mercury pollution were accompanied by severe human activities. The geoaccumulation index showed that mercury pollution in Hengshuihu wetland was at clean level; potential ecological risk index showed mercury contamination had a low ecological risk in Hengshuihu wetland.


Assuntos
Monitoramento Ambiental , Mercúrio/análise , Medição de Risco , Poluentes da Água/análise , Áreas Alagadas , China , Ecologia , Sedimentos Geológicos/química , Solo/química
17.
Huan Jing Ke Xue ; 37(11): 4357-4365, 2016 Nov 08.
Artigo em Chinês | MEDLINE | ID: mdl-29964692

RESUMO

Employing high-throughput sequencing as the method, this study analyzed the relationship between the water environment and the microbial community structure in the surface-flow constructed wetland. The results showed that: the mean Shannon-Wiener index was 6.57 and there were mainly 18 categories in the microbial community, including Proteobacterice (38.97%), Bacteroidetes (15.63%) etc. Of these, the total content of 22 genera was over 1%. The microbial biodiversity showed an increasing trend at the beginning and then turned to a decreasing trend in the flowing direction. The results also revealed that pH, ORP, NH4+-N, NO2--N and TN acted as important restricting factors for the microbial community.


Assuntos
Bactérias/classificação , Biodiversidade , Microbiologia da Água , Áreas Alagadas
18.
Microb Biotechnol ; 8(6): 1006-12, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25847617

RESUMO

Nostoc flagelliforme is a terrestrial edible cyanobacterium that grows in arid and semi-arid steppes. The continued over-exploitation in the last century has led to a sharp decline of this resource and a severe deterioration of the steppe ecology. Liquid-cultured N. flagelliforme serves as promising algal 'seeds' for resource restoration. In this study, macroscopic (or visible) aquatic-living colonies (MaACs) of N. flagelliforme were developed under weak light and high nitrogen conditions. In a 24 day shake-flask culture, MaACs were propagated by about 4.5-fold in biomass without loss of their macro-morphology; at the same time, the addition of weak UV-B treatment resulted in slightly bigger MaACs. Polyvinylpyrrolidone (PVP) k30, a water-soluble polymer, was used to generate the coating around MaACs, and after full desiccation, the coated MaACs could recover their photosynthetic physiological activity when rehydrated, with 4% PVP k30 for coating being most effective. In contrast, PVP k30-coated microscopic aquatic-living colonies of N. flagelliforme and non-coated MaACs showed no resistance to full desiccation. The macroscopic morphology or structure of MaACs should be crucial for the formation of protection by PVP k30 coating. PVP k30-coated MaACs were more approaching to actual application for resource restoration.


Assuntos
Dessecação , Viabilidade Microbiana , Nostoc/fisiologia , Estresse Fisiológico , Hidratação , Luz , Nitrogênio/metabolismo , Fotossíntese , Povidona/metabolismo
19.
Shanghai Kou Qiang Yi Xue ; 20(2): 152-8, 2011 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-21566864

RESUMO

PURPOSE: To study the curative effects, survival rate, migration and differentiation of bone mesenchymal stem cells (BMSCs) transplanted into rats with Sjogren's syndrome. METHODS: Model of Sjogren's syndrome was created in rats. BMSCs were isolated and cultured by using the preceding method. Then the pretreated BMSCs were identified and labeled by enhanced green fluorescent protein. BMSCs marked with enhanced green fluorescent protein (EGFP) or PBS were injected into the SMG of the Sjogren's syndrome rats via open surgery.Total static saliva flow rate was determined in rats. The daily amount of water in the normal group, the model group, the model treatment group and the model treatment control group was recorded. The survival rate, migration and differentiation of the BMSCs transplanted in the treatment group under fluorescence microscope was recorded. Student's t test was used for data analysis using SPSS 12.0 software package. RESULTS: Compared with the model treatment control group, the total static saliva flow rate of the model treatment group increased significantly, and the water they drank decreased significantly (P<0.05). In addition, BMSCs were distributed along the injection tract mostly in the first week,then BMSCs were mainly distributed in the stroma between the acinar in the second week and were distributed over other areas four weeks later. Immunohistochemical staining of amylzyme was not observed at the first week after transplantation. And at the 8th week the expression of amylzyme in the cytoplasm of the transplanted BMSCs was observed by immunohistochemical only in the model treatment group. CONCLUSION: Transplantation of BMSCs has certain treatment effect on Sjogren's syndrome.


Assuntos
Células da Medula Óssea , Células-Tronco Mesenquimais , Animais , Diferenciação Celular , Proteínas de Fluorescência Verde , Transplante de Células-Tronco Mesenquimais , Ratos , Ratos Sprague-Dawley , Síndrome de Sjogren
20.
Fa Yi Xue Za Zhi ; 26(6): 418-20, 2010 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-21425601

RESUMO

OBJECTIVE: To explore relationship between increase of fibrous and fatty in atrioventricular node (AVN) and narrowing of the AVN artery. To analyze the cause of pathological fibrosis and fatty infiltration in AVN. METHODS: One hundred and nineteen cases of sudden cardiac death determined by autopsy were selected and the histological sections were examined with Image-pro plus software to calculate the AVN area, AVN artery inside-diameter, AVN artery lumen area(LA) , AVN artery perimeter area(PA), fibrous area and fatty area. All cases were divided into two groups: narrowing of artery group and normal control group. The changes of the PA/LA value and the fibrous and fatty contents were evaluated. RESULTS: The PA/LA value is the highest in 21-40 age group. The difference of the fatty contents and total interstitial tissue was statistical significance in the two groups under 40 years of age. CONCLUSION: There is some relationship between the narrowing of the AVN artery and the increase of interstitial contents in AVN.


Assuntos
Nó Atrioventricular/patologia , Estenose Coronária/patologia , Vasos Coronários/patologia , Sistema de Condução Cardíaco/patologia , Adolescente , Adulto , Fatores Etários , Nó Atrioventricular/metabolismo , Criança , Morte Súbita Cardíaca/etiologia , Feminino , Fibrose , Patologia Legal , Sistema de Condução Cardíaco/metabolismo , Humanos , Metabolismo dos Lipídeos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
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