Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 72
Filter
1.
Front Oncol ; 14: 1368564, 2024.
Article in English | MEDLINE | ID: mdl-38694785

ABSTRACT

Ewing's Sarcoma (ES) is an rare, small round-cell sarcoma that predominantly occurs in children and young adults, with both skeletal and extraskeletal manifestations. However, pancreatic ES, due to its rarity, is infrequently featured in scholarly literature, with only a scant 43 reported instances. Our study describes a case of pancreatic ES in an 8-year-old boy who was found to have an abdominal mass. Following an exhaustive examination, the boy was diagnosed with a neoplasm in the pancreatic head and underwent a complex surgical procedure encompassing pancreatoduodenectomy and partial transverse colectomy. Immunohistochemical assays confirmed the neoplastic cells' positivity for Cluster of Differentiation 99(CD99), Vimentin, and NK2 Homeobox 2(NKX2.2), while genomic testing identified an EWSR1-FLI1(Ewing Sarcoma Breakpoint Region 1-Friend Leukemia Integration 1) gene fusion. This led to a conclusive diagnosis of pancreatic Ewing's Sarcoma. The patient underwent seven cycles of adjuvant chemotherapy, alternating between VDC (Vincristine, Doxorubicin, Cyclophosphamide) and IE (Ifosfamide, Etoposide) tri-weekly, but did not undergo radiotherapy. At present, the patient remains neoplasm-free. Through our case analysis and comprehensive review of the existing literature, we aim to underscore th rarity of pancreatic Ewing's sarcoma and to highlight the efficacy of our individualized therapeutic approach.

2.
Inorg Chem ; 62(29): 11372-11380, 2023 Jul 24.
Article in English | MEDLINE | ID: mdl-37431607

ABSTRACT

[n]Cycloparaphenylenes ([n]CPPs, n denotes the number of phenyl groups) are difficult to synthesize because of the strain related to their bent phenyl rings. In particular, the strain in [3]CPP is high enough to destroy the π electron delocalization, leading to the spontaneous structural transition to an energetically more stable "bond-shift" (BS) isomer ([3]BS). In this contribution, we propose to achieve [3]CPP by enhancing the π electron delocalization through hosting a guest metal atom. Our computations revealed that Sc could stabilize [3]CPP by forming the [Sc©[3]CPP]+ complex through the favorable π-Sc donation-backdonation interactions. Thermodynamically, the binding energy between the Sc atom and [3]CPP was -205.7 kcal/mol, which could well compensate not only the energy difference of 44.2 kcal/mol between [3]CPP and [3]BS but also the extremely high strain energy of 170.3 kcal/mol in [3]CPP. Simultaneously, the [Sc©[3]CPP]+ complex is stable up to 1500 K in dynamic simulations, suggesting its high viability in the synthesis.

3.
Front Surg ; 9: 922930, 2022.
Article in English | MEDLINE | ID: mdl-36211296

ABSTRACT

Background: A prospective controlled study was conducted to compare the short-term clinical results and postoperative complications of minimally invasive transforaminal lumbar decompression and fusion (minimally invasive surgery transforaminal lumbar interbody fusion, MIS-TLIF) and percutaneous endoscope-assisted transforaminal lumbar interbody fusion (endoscopic lumbar interbody fusion, Endo-LIF) in the treatment of single-segment degenerative lumbar diseases, to provide some scientific guidance for clinicians to select surgical treatment for patients with lumbar degeneration. Methods: From October 2020 to October 2021, a total of 62 patients were enrolled, with 31 patients in the MIS-TLIF group and 31 patients in the Endo-LIF group. All patients were followed up for 6 months. The following information from the two groups of patients was recorded: (1) operation time, radiation exposure time, intraoperative blood loss, bed rest time, and hospital stay; (2) ODI score (The Oswestry Disability Index), low back pain VAS score (Visual Analogue Scale), and lumbar vertebra JOA score (Japanese Orthopaedic Association Scores) 1 day before the operation; 1, 3, 6 days after operation; and 1, 3 and 6 months after operation. (3) X-ray evaluations of lumbar fusion at the last follow-up. Results: There were significant differences in operation time, intraoperative fluoroscopy time, and hospitalization cost between the two groups. The MIS-TLIF group was significantly better than the Endo-LIF group, and the intraoperative bleeding volume of the Endo-LIF group was significantly better than that of the MIS-TLIF group, but there was no significant difference in postoperative bed rest time and postoperative hospital stay. There was no significant difference in the scores of ODI, VAS, and JOA between the two groups before and after the operation. At the last follow-up, the fusion rate was 100% in the MIS-TLIF group and 100% in the Endo-LIF group. Conclusions: There was no significant difference in short-term clinical efficacy and safety between Endo-LIF and MIS-TLIF in the treatment of single-segment degenerative lumbar diseases, but MIS-TLIF was significantly better than Endo-LIF in terms of the operation time, hospitalization cost, and fluoroscopy time, and Endo-LIF was significantly better than MIS-TLIF in terms of intraoperative blood loss.

4.
Front Physiol ; 13: 953423, 2022.
Article in English | MEDLINE | ID: mdl-36187768

ABSTRACT

Background: The aim of this study was to explore the significance of three-dimensional double-echo steady-state (3D-DESS) sequence and multidetector computed tomography (CT) plain scan in the diagnosis of lumbar disc herniation (LDH) remaining controversial in conventional magnetic resonance imaging (MRI), and to compare the efficiency between 3D-DESS and CT in diagnosing controversial patients by conventional MRI. Methods: A total of 61 patients with controversial LDH diagnosed by conventional MRI were collected. Before operation, the disease of these patients was further confirmed by 3D-DESS sequences and continuous CT plain scan from L3 to S1. Finally, for patients whose postoperative curative effect was marked and symptoms were obviously alleviated, the sensitivity, specificity and accuracy. Results: Among, 59 patients with remarkably relieved symptoms after operation were included, and 2 patients with varying degrees of non-remission of pain and partial dysfunction after operation were excluded. The sensitivity, specificity and accuracy of 3D-DESS were 94.6, 100 and 94.9%, respectively, and those of CT were 75.0, 33.3 and 72.9%, respectively. Conclusion: 3D-DESS is a very useful diagnostic method for patients with some special types of LDH that remain controversial in conventional imaging diagnostic methods. Through 3D-DESS, the morphology of lumbosacral nerve roots can be directly observed, which is conducive to the improvement of the sensitivity, specificity and accuracy, thus further reducing the misdiagnosis rate. Moreover, 3D-DESS plays a guiding role in the formulation of operative methods.

5.
PLoS One ; 17(5): e0268679, 2022.
Article in English | MEDLINE | ID: mdl-35588136

ABSTRACT

Ilex dabieshanensis K. Yao & M. B. Deng is not only a highly valued tree species for landscaping, it is also a good material for making kuding tea due to its anti-inflammatory and lipid-lowering medicinal properties. Utilizing next-generation and long-read sequencing technologies, we assembled the whole chloroplast genome of I. dabieshanensis. The genome was 157,218 bp in length, exhibiting a typical quadripartite structure with a large single copy (LSC: 86,607 bp), a small single copy (SSC: 18,427 bp) and a pair of inverted repeat regions (IRA and IRB: each of 26,092 bp). A total of 121 predicted genes were encoded, including 113 distinctive (79 protein-coding genes, 30 tRNAs, and 4 rRNAs) and 8 duplicated (8 protein-coding genes) located in the IR regions. Overall, 132 SSRs and 43 long repeats were detected and could be used as potential molecular markers. Comparative analyses of four traditional Ilex tea species (I. dabieshanensis, I. paraguariensis, I. latifolia and I. cornuta) revealed seven divergent regions: matK-rps16, trnS-psbZ, trnT-trnL, atpB-rbcL, petB-petD, rpl14-rpl16, and rpl32-trnL. These variations might be applicable for distinguishing different species within the genus Ilex. Phylogenetic reconstruction strongly suggested that I. dabieshanensis formed a sister clade to I. cornuta and also showed a close relationship to I. latifolia. The generated chloroplast genome information in our study is significant for Ilex tea germplasm identification, phylogeny and genetic improvement.


Subject(s)
Genome, Chloroplast , Ilex , Aquifoliaceae/genetics , Ilex/genetics , Phylogeny , Tea
6.
Int J Phytoremediation ; 24(14): 1557-1566, 2022.
Article in English | MEDLINE | ID: mdl-35297705

ABSTRACT

Pot and field trials were conducted to investigate Cd uptake and phytoremediation efficiency of two Brassica napus cultivars (QY-1 and SYH) with applied water-soluble chitosan (WSC, Pot: 0, 2% and 4%; Field: 0 and 10 g·m-2) grown in Cd-contaminated soils. The results from the pot and field trials generally showed that WSC treatments significantly increased Cd concentrations in shoot and root tissues by 33.77-159.71% (except for SYH/JY) and 7.42-168.71% of two B. napus cultivars compared with the control (p < 0.05). The uptake of Cd by shoots of SYH was obviously higher than by shoots of QY-1 treated with WSC under pot and field conditions, which was 1.54-2.22 times than that of QY-1 (p < 0.05). The results indicated that 2% WSC treatment significantly increased the water-soluble and acid extractable Cd in rhizosphere soils of both B. napus cultivars. Furthermore, Cd concentrations in the oils of two B. napus cultivars with applied WSC (10 g·m-2) grown under field conditions were not significantly different from commercial rapeseed oils. Rapeseed oil of B. napus is not only an edible oil with high nutritional value, but it can also be converted into biomass diesel that can be used as a substitute for petroleum diesel.


Subject(s)
Brassica napus , Chitosan , Soil Pollutants , Cadmium/analysis , Biodegradation, Environmental , Soil Pollutants/analysis , Farms , Water , Soil , Oils
7.
BMC Plant Biol ; 21(1): 503, 2021 Oct 30.
Article in English | MEDLINE | ID: mdl-34717537

ABSTRACT

BACKGROUND: In angiosperms, phenotypic variation of floral organs is often considered as the traditional basis for the evolutionary relationship of different taxonomic groups above the species level. However, little is known about that at or below the species level. Here, we experimentally tested the phenotypic variation of Malus floral organs using combined methods of intraspecific uniformity test, interspecific distinctness analysis, principal component analysis, Pearson correlation analysis, and Q-type cluster analysis. The ancestor-inclined distribution characteristic analysis of Malus species and cultivars floral attributes was also carried out, so as to explore its taxonomic significance. RESULTS: 15/44 phenotypic traits (e.g., flower shape, flower type, flower diameter, ...) were highly consistent, distinguishable, and independent and could be used as the basis for Malus germplasm taxonomy. The studied 142 taxa were divided into two groups (A, B) and five sub-groups (A1, A2, B1, B2, B3), with significantly variable floral phenotypic attributes between groups and within sub-groups. Malus natural species were relatively clustered in the same section (series) while homologous cultivars showed evidence of ancestor-inclined distribution characteristics. However, no significant correlation between the evolutionary order of sections (Sect. Docyniopsis → Sect. Chloromeles → Sect. Sorbomalus → Sect. Eumalus) and group/sub-groups (B3 → B2 → B1 → A). CONCLUSIONS: Phenotypic variation of floral organs could better explore the genetic relationship between Malus taxa. The findings improved our cognition of floral phenotypic variation taxonomic significance under the species level.


Subject(s)
Biological Variation, Population , Classification , Flowers/anatomy & histology , Flowers/genetics , Malus/anatomy & histology , Malus/classification , Malus/genetics , Biological Evolution , China , Genetic Variation , Genotype
8.
Chem Commun (Camb) ; 57(47): 5806-5809, 2021 Jun 10.
Article in English | MEDLINE | ID: mdl-33999984

ABSTRACT

We predicted the stable alkaline earth complexes M(Cp)3- (M = Ca, Sr, Ba; Cp = cyclopentadienyl), where the M centers were in their stable +2 oxidation state and mimicked the bonding behaviour of transition metals by participating in bonding with the π orbitals of Cp ligands using their d orbitals.

9.
Neurotox Res ; 39(4): 1103-1115, 2021 Aug.
Article in English | MEDLINE | ID: mdl-33689146

ABSTRACT

Although many studies have reported toxic effects of cadmium (Cd) and lead (Pb) in the central nervous system, few studies have investigated the combined toxicity of Cd and Pb. The mechanisms by which these combined heavy metals induce toxicity, as well as effective means to exert neuroprotection from these agents, remain poorly understood. To investigate the protective effects of alpha-lipoic acid (α-LA) on Cd- and/or Pb-induced cortical damage in rats, 48 Sprague-Dawley rats were exposed to drinking water containing 50 mg/L of Cd and/or 300 mg/L of Pb for 12 weeks, in the presence or absence of α-LA co-treatment (50 mg/kg) via gavage. We observed that exposure to Cd and/or Pb decreased the brain weight/body weight ratio and increased Cd and/or Pb contents as well as ultrastructural damage to the cerebral cortex. Cd and/or Pb also induced endoplasmic-reticulum (ER) stress and activated Fas (CD95/APO-1)/Fas ligand (FasL) and mitochondrial apoptotic pathways. Furthermore, co-treatment of Cd and Pb further exacerbated part of these phenotypes than treatment of Cd or Pb alone. However, simultaneous supplementation with α-LA attenuated Cd and/or Pb-induced neurotoxicity by increasing the brain weight/body weight ratio, reducing Cd and/or Pb contents, ameliorating both nuclear/mitochondrial damage and ER stress, and attenuating activation of Fas/FasL and mitochondrial apoptotic pathways. Collectively, our results indicate that the accumulation of Cd and/or Pb causes cortical damage and that α-LA exerts protection against Cd- and/or Pb-induced neurotoxicity. These findings highlight that α-LA may be exploited for the treatment and prevention of Cd- and/or Pb-induced neurotoxicity.


Subject(s)
Cadmium/toxicity , Cerebral Cortex/drug effects , Endoplasmic Reticulum Stress/drug effects , Fas Ligand Protein/antagonists & inhibitors , Lead/toxicity , Thioctic Acid/pharmacology , fas Receptor/antagonists & inhibitors , Animals , Antioxidants/pharmacology , Apoptosis/drug effects , Apoptosis/physiology , Cerebral Cortex/metabolism , Cerebral Cortex/ultrastructure , Endoplasmic Reticulum Stress/physiology , Fas Ligand Protein/metabolism , Female , Mitochondria/drug effects , Mitochondria/metabolism , Mitochondria/ultrastructure , Rats , Rats, Sprague-Dawley , fas Receptor/metabolism
10.
Huan Jing Ke Xue ; 42(2): 900-908, 2021 Feb 08.
Article in Chinese | MEDLINE | ID: mdl-33742885

ABSTRACT

In order to fully explore the spatial distribution of soil heavy metal contaminants in farmland soil surrounding a typical industrial area in Dakuai town, Xinxiang city, Henan Province, the concentrations of As, Cd, Cr, Cu, Ni, Pb, and Zn in the surface soil and within the soil profile were determined and assessed. The principal components were also analyzed for source apportionment to provide a theoretical basis for the control and prevention of heavy metal pollution. According to the results, the soils in the study area are severely contaminated by Cd and Cu and moderated contaminated by As due to the battery manufacture and Cu (e.g., pipe and wire) processing. The concentrations of Cd, Cu, and As in soils were (2.56±1.23) mg·kg-1, (205.58±157.49) mg·kg-1, and (15.27±4.14) mg·kg-1, respectively, which exceeds standards by 100%, 89.44%, and 3.40%, respectively. Accounting for the influence of pollution sources, terrain, runoff erosion, and prevailing wind direction, all heavy metal concentrations were higher in the south direction, lower in the north direction. The concentrations of Cd and Cu in soil profile samples decreased with depth, with highest concentrations at the surface, indicating the strong effect of industrial activities. Arsenic concentrations varied little with soil depth due to its strong migration ability in alkaline soil, again suggesting an industrial source. Among them, the soil of study area was severely contaminated by Cd and Cu (Level 5). Cd poses a severe potential ecological risk (Level 5) and Cu poses a medium risk (Level 2) in the study soils, while other heavy metals show low potential ecological risk (Level 1). The order of the risk identified was Cd > Cu > Ni > As > Pb > Cr > Zn. In addition, the combined potential ecological risk of heavy metals in the target area is severe. The principal component analysis showed that the high As, Cd, and Cu contents are mainly derived from industrial areas. Therefore, it is urgent to remediate Cd and Cu soil contamination in this area and implement precautions to limit As contamination.


Subject(s)
Metals, Heavy , Soil Pollutants , China , Cities , Environmental Monitoring , Farms , Metals, Heavy/analysis , Risk Assessment , Soil , Soil Pollutants/analysis
11.
Dalton Trans ; 50(7): 2654-2662, 2021 Feb 23.
Article in English | MEDLINE | ID: mdl-33527940

ABSTRACT

We present a detailed DFT mechanistic study on the first Ni-catalyzed direct carbonyl-Heck coupling of aryl triflates and aldehydes to afford ketones. The precatalyst Ni(COD)2 is activated with the phosphine (phos) ligand, followed by coordination of the substrate PhOTf, to form [Ni(phos)(PhOTf)] for intramolecular PhOTf to Ni(0) oxidative addition. The ensuing phenyl-Ni(ii) triflate complex substitutes benzaldehyde for triflate by an interchange mechanism, leaving the triflate anion in the second coordination sphere held by Coulomb attraction. The Ni(ii) complex cation undergoes benzaldehyde C[double bond, length as m-dash]O insertion into the Ni-Ph bond, followed by ß-hydride elimination, to produce Ni(ii)-bound benzophenone, which is released by interchange with triflate. The resulting neutral Ni(ii) hydride complex leads to regeneration of the active catalyst following base-mediated deprotonation/reduction. The benzaldehyde C[double bond, length as m-dash]O insertion is the rate-determining step. The triflate anion, while remaining in the second sphere, engages in electrostatic interactions with the first sphere, thereby stabilizing the intermediate/transition state and enabling the desired reactivity. This is the first time that such second-sphere interaction and its impact on cross-coupling reactivity has been elucidated. The new insights gained from this study can help better understand and improve Heck-type reactions.

12.
RSC Adv ; 11(26): 15841-15846, 2021 Apr 26.
Article in English | MEDLINE | ID: mdl-35481175

ABSTRACT

NBe5H n n-3 (n = 0-5) (0A-5A) species with a novel planar pentacoordinate nitrogen (ppN) were designed by the isoelectronic substitution of the C atom in planar pentacoordinate carbon (ppC) species CBe5H n n-4 (n = 0-5) with an N atom. The highly flexible H atoms found in ppC species CBe5H2 2- and CBe5H3 - were fixed upon the nitrogen substitution, as mirrored by the non-flexible H atoms in their ppN analogues NBe5H2 - (2A) and NBe5H3 (3A). Moreover, the N atom was found to fit the H-surrounded Be5 rings better than the C atom because the ppC species CBe5H4 and CBe5H5 + adopted non-planar structures due to size-mismatch between the C atom and the H-surrounded Be5 ring, but their ppN analogues NBe5H4 + (4A) and NBe5H5 2+ (5A) adopted perfect planar structures. The electronic structure analyses revealed that the N atoms in 0A-5A were involved in four doubly occupied orbitals, including three six-center two-electron (6c-2e) σ bonds and one 6c-2e π bond. Therefore, these ppN species not only obey the octet rule, but also possess the interesting σ and π double aromaticity, which contributes to the stabilization. Consequently, 2A, 4A, and 5A are charged kinetically viable global energy minima, and are suitable for the gas phase generation and spectroscopic characterization.

13.
Huan Jing Ke Xue ; 41(9): 4226-4233, 2020 Sep 08.
Article in Chinese | MEDLINE | ID: mdl-33124304

ABSTRACT

A field experiment with an orthogonally designed experiment L9(34) was designed to investigate the effect of different N, P, and K levels on plant growth and Cd uptake by Hylotelephium spectabile. The results showed that the biomass of H. spectabile significantly increased with the N application rate. The highest dry weight in the shoot occurred in the treatments with a high level of N (337.5 kg ·hm-2), which was 0.86-2.00 times higher than the value with no fertilizer treatment. The addition of K contributed to promoting the Cd absorption of H. spectabile, while no effect was observed when N and P were added. Consequently, NPK fertilizers contribute to increasing the Cd uptake of H. spectabile, and the N and K fertilizer play important role in plant growth and Cd absorption respectively. Moreover, the effect of fertilizers on Cd uptake of H. spectabile was in the order of N > K > P, which indicated that N fertilizer was the main factor for promoting the Cd phytoextraction efficiency of H. spectabile by increasing the biomass. Therefore, the application of high levels of N combined with moderate levels of P and K will be an effective approach to improve the Cd phytoremediation efficiency of H. spectabile by promoting its growth, and the Cd uptake can be increased by a factor of 0.9-2.2 compared to no fertilizer treatment condition.


Subject(s)
Cadmium , Soil Pollutants , Biodegradation, Environmental , Cadmium/analysis , Fertilizers/analysis , Nitrogen , Nutrients , Soil , Soil Pollutants/analysis
14.
Huan Jing Ke Xue ; 41(2): 970-978, 2020 Feb 08.
Article in Chinese | MEDLINE | ID: mdl-32608759

ABSTRACT

A hydroponic experiment was conducted to explore the differences in growth status and Cd accumulation characteristics of two Brassica napus L. cultivars (QY-1 and SYH) under different concentrations of cadmium (Cd) stress (0, 2, and 5 mg·L-1). The Cd subcellular compartmentalization and antioxidant enzyme activities were determined to elucidate the intrinsic mechanism of the differences in the Cd accumulation capacity between the two cultivars of Brassica napus L. Furthermore, field trials were conducted to further verify the differences in phytoremediation of the two cultivars. Results show that neither of the cultivars exhibited obvious growth inhibition under Cd stress. Under the 2 mg·L-1 Cd condition, there were no significant differences in shoot Cd concentrations between the two cultivars. Under 5 mg·L-1 Cd condition, however, the Cd concentrations in both shoot and root of SYH were significantly higher than that of QY-1, which increased by 32.05% and 99.57%, respectively. In addition, the bioconcentration factor (BCF) of the root in SYH is significantly higher than that of QY-1. The subcellular Cd distribution in leaves of the two cultivars of Brassica napus L. showed that, with an increase of Cd stress, Cd concentrations of heat stable protein (HSP) and metal-rich granule (MRG) fractions in leaves significantly increased by 143.69% and 118.91% for QY-1, and by 63.34% and 118.91% for SYH. Thus, the segregation of Cd in HSP and MRG, which was reported to be biological detoxified metal fractions (BDM), might play an important role in the detoxification of Brassica napus L. at a subcellular level under Cd stress. Moreover, the distribution of Cd in the cellular debris fraction might be another important factor contributing to the differences in Cd accumulation of the two Brassica napus L. cultivars, which was 4.41 times higher in SYH than in QY-1 under Cd stress. The results of the antioxidant enzyme activities of two Brassica napus L. cultivars showed that, under the 5 mg·L-1 Cd condition, the antioxidant enzyme system may represent an important detoxification mechanism for QY-1 to cope with stress induced by high concentrations of Cd, while SYH is more effective in reducing the toxicity of Cd by separation of Cd into BDM fractions. The results of the field trial confirmed that the Cd concentrations in the above- and underground parts of SYH were 2.34 and 1.43 times higher than in QY-1, respectively. Therefore, SYH possess a higher Cd phytoextraction capacity than QY-1, and might be a good candidate for the remediation of moderate and mildly Cd-contaminated farmland.


Subject(s)
Brassica napus/metabolism , Cadmium/metabolism , Soil Pollutants/metabolism , Biodegradation, Environmental , Plant Roots , Plant Shoots
15.
Phys Chem Chem Phys ; 22(30): 17062-17067, 2020 Aug 14.
Article in English | MEDLINE | ID: mdl-32568316

ABSTRACT

Computational design has played an important role in planar hyper-coordinate carbon (phC) chemistry. However, none of numerous computationally predicted phC species were subsequently successfully synthesized in the condensed phase, perhaps due to the frustrating issue of oxidation. In the present work, we studied the influence of stepwise oxidation on the structure, stability, and properties of phC species using the milestone planar pentacoordinate carbon (ppC) species CAl5+ as an example. Our results indicated that the ppC structure of CAl5+ would be directly destroyed with one, two, or six O atom(s) per molecule present and indirectly with three or four O atoms, but maintained with five O atoms due to the ppC isomer of CAl5O5+ being a kinetically stable global energy minimum displaying σ and π double aromaticity. Moreover, the magnitudes of the first to fifth vertical oxygen affinities (VOAs) for CAl5+ were determined to be very high (-85.5 to -116.3 kcal mol-1), probably due to the existence of peripheral diffuse Al-Al bond(s). However, the sixth VOA was reduced significantly to -50.2 kcal mol-1, consistent with the absence of any diffuse Al-Al bond in the corresponding CAl5O5+ species. So CAl5O5+ may be insensitive to oxidation. Therefore, the ppC species D5h CAl5O5+ might be resistant to being degraded under a delicate control of oxidation level (producing five O atoms per CAl5+ molecule).

16.
Ying Yong Sheng Tai Xue Bao ; 31(8): 2817-2830, 2020 Aug.
Article in Chinese | MEDLINE | ID: mdl-34494805

ABSTRACT

High temperature stress occurs frequently in rice due to global warming. High-temperature hazard during the booting-flowering and grain-filling stages is one of the major factors limiting rice yield and quality. Here, we summarized the occurrence characteristics (identification, classification, region, and time) of high-temperature hazards, and the effects of high temperature on rice growth and development, including physiology, grain yield, and grain quality. Furthermore, we reviewed molecular biology aspects including quantitative trait locus mapping, transcriptome analysis, proteome analysis, and the monitoring, early warning, risk assessment of high-temperature hazards in rice. The defensive measures against high temperature in rice including selecting heat-resistant varieties, improving field management practices and spraying exogenous substances were intensively described. Finally, future research work on high-temperature hazards in rice was prospected to provide the scientific support for rice high-temperature defense, agricultural disaster reduction, and agricultural efficiency improvement.


Subject(s)
Oryza , Edible Grain , Hot Temperature , Oryza/genetics , Proteome , Temperature
17.
Angew Chem Int Ed Engl ; 58(48): 17365-17374, 2019 Nov 25.
Article in English | MEDLINE | ID: mdl-31498532

ABSTRACT

We report the synthesis and spectroscopic identification of the trisbenzene complexes of strontium and barium M(Bz)3 (M=Sr, Ba) in low-temperature Ne matrix. Both complexes are characterized by a D3 symmetric structure involving three equivalent η6 -bound benzene ligands and a closed-shell singlet electronic ground state. The analysis of the electronic structure shows that the complexes exhibit metal-ligand bonds that are typical for transition metal compounds. The chemical bonds can be explained in terms of weak donation from the π MOs of benzene ligands into the vacant (n-1)d AOs of M and strong backdonation from the occupied (n-1)d AO of M into vacant π* MOs of benzene ligands. The metals in these 20-electron complexes have 18 effective valence electrons, and, thus, fulfill the 18-electron rule if only the metal-ligand bonding electrons are counted. The results suggest that the heavier alkaline earth atoms exhibit the full bonding scenario of transition metals.

18.
Dalton Trans ; 48(19): 6581-6587, 2019 May 15.
Article in English | MEDLINE | ID: mdl-31016316

ABSTRACT

A current project in metal-metal bonding chemistry is to achieve ultrashort metal-metal distances (USMMDs, denoted by dM-M < 1.900 Å) between main group metal beryllium atoms. A valid way for achieving such USMMDs is the substitution of a carbon atom in a planar pentacoordinate environment with the isoelectronic Be2 moiety. In the present work, we report our recent findings that a similar substitution can be applied to the carbon atom in a planar hexacoordinate environment. Using species CN3Be3+ and CO3Li3+ and related analogues as the templates, the Be2N3M3+ (M = Be, Mg, Ca) and Be2O3M3+ (M = Li, Na, K) species with axial ultrashort Be-Be distances of 1.627-1.870 Å were designed computationally. The ultrashort Be-Be distances in these species represent a balance between the lengthening effect of axial Be-Be electrostatic interactions and the shortening effects of the strong X-Be bonding and repulsive X-X-X electrostatic interactions. In addition, the shorter axial Be-Be distances were determined firstly by the smaller size of the bridging electronegative X atoms and secondly by the lower electronegativity of the peripheral M atoms, while the stabilities of the newly designed species were closely related to the types of valence electron pairs, whereby the localized two-center two-electron bonds were better for stabilization than the non-bonding valence lone pairs. Among the newly designed species, Be2N3Be3+ and Be2N3Mg3+ were characterized to be the kinetically stable global minima, thereby providing promising targets for the experimental realization of species with USMMDs between main group metals.

20.
Ann Vasc Surg ; 54: 282-289, 2019 Jan.
Article in English | MEDLINE | ID: mdl-30103053

ABSTRACT

BACKGROUND: In the present study, we aimed to inspect the correlation of interleukin-18 (IL-18) and high-sensitivity C-reactive protein (hs-CRP), if any present, with the occurrence of perioperative deep vein thrombosis (DVT) in patients suffering from an ankle fracture (AF). METHODS: Sixty-seven AF patients with complicated DVT (DVT group) and 448 AF patients without DVT (non-DVT group) were enrolled in the present study. To begin with, hemorheological indexes were detected. Turbidimetric immunoassay and enzyme-linked immunosorbent assay were used for the determination of the expressions of hs-CRP and IL-18, respectively. Coagulation method was used to detect prothrombin time (PT), thrombin time (TT), fibrinogen, and activated partial thromboplastin time (APTT). Logistic regression analysis was used to analyze the independent risk factors for DVT occurrence in AF patients after operation. RESULTS: The results revealed that the DVT group presented an increased expression of hs-CRP and IL-18 1 day before operation and 1, 3, and 7 days after operation in comparison with the non-DVT group. The DVT group also had increased levels of PT, APTT, and prolonged TT and fibrinogen at 3 and 7 days after operation compared to the non-DVT group. After operation, it was observed that the patients in the DVT group had increased plasma viscosity, whole blood reduced viscosity, red blood cell (RBC) aggregation index, RBC deformation index, erythrocyte sedimentation rate, and declined erythrocrit. The independent risk factors for the occurrence of DVT were identified to be high-energy injury, TT, fibrinogen, hs-CRP, and IL-18 in AF patients after operation. CONCLUSIONS: Based on the results obtained from the study, it was concluded that AF patients with DVT have higher levels of IL-18 and hs-CRP expressions, which is associated with the occurrence and development of DVT. These results may be particularly useful for diagnosis and treatment on DVT occurrence in AF patients.


Subject(s)
Ankle Fractures/complications , C-Reactive Protein/analysis , Interleukin-18/blood , Venous Thrombosis/etiology , Adult , Age Factors , Aged , Ankle Fractures/blood , Ankle Fractures/surgery , Biomarkers/blood , Blood Coagulation Tests , Female , Humans , Logistic Models , Male , Middle Aged , Perioperative Period , Risk Factors , Sex Factors , Venous Thrombosis/blood
SELECTION OF CITATIONS
SEARCH DETAIL
...