Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 27
Filter
1.
BMC Ophthalmol ; 22(1): 123, 2022 Mar 15.
Article in English | MEDLINE | ID: mdl-35287632

ABSTRACT

BACKGROUND: To investigate the structural and functional changes of the retina in patients with different degrees of internal carotid artery (ICA) stenosis. METHODS: This cross-sectional study included patients with varying degrees ICA stenosis. Clinical characteristics of 41 patients were collected after being divided into four groups according to the ICA stenosis indicated by computed tomographic angiography (Group 0: without ICA stenosis, Group 1: ipsilateral slight ICA stenosis, Group 2: ipsilateral moderate ICA stenosis, Group 3: ipsilateral severe ICA stenosis). Retinal vessel caliber (RVC) was measured quantitatively with the Integrative Vessel Analysis software. The retinal sensitivity was examined with the MP-3 microperimeter. The relationships among central retinal artery equivalent (CRAE), central retinal vein equivalent, arteriole to venule ratio (AVR), mean retinal sensitivity (MS) and ICA stenosis degree were analysed. RESULTS: The CRAE in Group 3 were significantly smaller compared with Group 0, Group 1 and Group 2 (P < 0.001, P < 0.001, P = 0.002). Significant decrease was found between Group 3 with other groups in MS at fovea (P < 0.001, P < 0.001, P = 0.002). Moreover, there was a positive correlation found between MS and CRAE (Beta = 0.60, P < 0.001 at fovea; Beta = 0.64, P < 0.001 at 2 degree; Beta = 0.60, P < 0.001 at 4 degree; Beta = 0.55, P < 0.001 at 8 degree; Beta = 0.53, P < 0.001 at 12 degree). CONCLUSIONS: The present study revealed smaller CRAE and AVR in ipsilateral severe ICA stenosis patients. And the MS decreased in patients with severe ICA stenosis. In addition, MS had a positive correlation with CRAE.


Subject(s)
Carotid Stenosis , Retinal Artery , Carotid Artery, Internal , Carotid Stenosis/diagnostic imaging , Cross-Sectional Studies , Humans , Retina
2.
J Stroke Cerebrovasc Dis ; 27(12): 3396-3403, 2018 Dec.
Article in English | MEDLINE | ID: mdl-30243729

ABSTRACT

IMM-H004 [7-hydroxy-5-methoxy-4-methyl-3-(4-methylpiperazin-1-yl)-coumarin] is a novel derivative of coumarin, which played neuroprotective roles in brain ischemia in rats in previous studies. Although antiapoptosis and improving synapsis structure were proved, the effects and mechanisms of IMM-H004 in brain ischemia need further study. In this paper, the effect of IMM-H004 on H2O2-induced neurotoxicity in pheochromocytoma (PC12) cells was researched. Morphological observation, MTT method and PI/Hoechst staining were used to indicate cell viability and apoptosis. JC-1 and DCFH-DA were used to test mitochondrial membrane potential (MMP) and reactive oxygen species (ROS), respectively. The antioxidative activity was detected by Glutathione (GSH) and Total Antioxidant Capacity (TAC) Assay kits. Western blot was used to test apoptosis related proteins. Our results showed that treatment with 1-10 µM IMM-H004 markedly increased cell viability and decreased cell apoptosis induced by H2O2. Moreover, 1-10 µM IMM-H004 could enhance MMP and protect mitochondrial function. 1-10 µM IMM-H004 also could lower the ROS and raise the GSH and TAC level. Furthermore, 1-10 µM IMM-H004 could decrease the ratio of Bax/Bcl-2 and increase the ratio of p-AKT/AKT, which were related to apoptosis and survival. All these indicated that IMM-H004 protects PC12 cells against H2O2-induced neurotoxicity. Antioxidative and antiapoptosis may be the mechanisms of IMM-H004 in brain ischemia. These studies indicate that IMM-H004 might be a potential drug for treatment brain ischemia.


Subject(s)
Antioxidants/pharmacology , Apoptosis/drug effects , Coumarins/pharmacology , Hydrogen Peroxide/toxicity , Neuroprotective Agents/pharmacology , Animals , Antioxidants/chemistry , Apoptosis/physiology , Cell Survival/drug effects , Cell Survival/physiology , Coumarins/chemistry , Dose-Response Relationship, Drug , Membrane Potential, Mitochondrial/drug effects , Molecular Structure , Neuroprotective Agents/chemistry , Oxidative Stress/drug effects , Oxidative Stress/physiology , PC12 Cells , Proto-Oncogene Proteins c-akt/metabolism , Proto-Oncogene Proteins c-bcl-2/metabolism , Rats , bcl-2-Associated X Protein/metabolism
3.
J Colloid Interface Sci ; 662: 149-159, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38340514

ABSTRACT

Efficient and stable oxygen reduction reaction (ORR) catalysts are essential for constructing reliable energy conversion and storage devices. Herein, we prepared noble metal-free FeCoNiMnV high-entropy alloy supported on nitrogen-doped carbon nanotubes (FeCoNiMnV HEA/N-CNTs) by a one-step pyrolysis at 800 °C, as certificated by a set of characterizations. The graphitization degree of the N-CHTs was optimized by tuning the pyrolysis temperature in the control groups. The resultant catalyst greatly enhanced the ORR characteristics in the alkaline media, showing the positive onset potential (Eonset) of 0.99 V and half-wave potential (E1/2) of 0.85 V. More importantly, the above FeCoNiMnV HEA/N-CNTs assembled Zn-air battery exhibited a greater open-circuit voltage (1.482 V), larger power density (185.12 mW cm-2), and outstanding cycle stability (1698 cycles, 566 h). This study provides some valuable insights on developing sustainable ORR catalysts in Zn-air batteries.

4.
Ying Yong Sheng Tai Xue Bao ; 35(4): 1150-1158, 2024 Apr 18.
Article in Zh | MEDLINE | ID: mdl-38884250

ABSTRACT

Functional traits are indicators of the responses and adaptation of organisms to environmental changes and cascade to a series of ecosystem functions. The functional traits of soil animals are sensitive to environmental factors and may characterize and predict the changes of ecosystem functions. Multiple dimensions of biodiversity that combing species, phylogenetic, and functional diversity improves the understanding of distribution patterns, community assembly mechanisms and ecosystem functions of soil animals. In this review, we listed the categories of soil animal functional traits and their ecological significance, and summarized current researches on the responses of soil animal communities to environmental changes and the community assembly processes based on trait-based approaches. We proposed to strengthen the study on the impacts of eco-evolution processes of biotic interactions to soil animal functional traits, establish the database of soil animal functional traits, and apply trait-based approaches in the ecological restoration in the future, which would benefit soil biodiversity conservation and sustainability of soil ecosystems.


Subject(s)
Biodiversity , Ecosystem , Soil , Animals , Conservation of Natural Resources , Ecology , Animal Distribution
5.
Zootaxa ; 3636: 525-46, 2013.
Article in English | MEDLINE | ID: mdl-26042309

ABSTRACT

Nipponentomnon imadatei sp. nov. from Northeast China and Nippon entomon taiga sp. nov. from Siberia, Russia are described. Nipponentornon heterothrixi Yin & Xie is redescribed based on type materials and lectotype and paralectotypes are designed for the species. Nipponentonon bidentatumn and N. nippon are reported for the first time from China. Nipponentornon imnadatei sp. nov. is characterized by a short labrum, absence of seta Pla on tergite VII and presence of three A-setae on sternites IV-VI. It is similar to N. jaceki from the Russian Far East, but differs in the shape of the comb, shape of setaß1 on the foretarsus, length of sensillum e on the foretarsus, and in chaetotaxy on tergite I and sternites IV-VI. Nipponentomnon taiga sp. nov. is characterized by a short labrum, presence of seta P2a' on nota, seta P0a on tergite I, seta Pla on tergites I-VII, and absence of seta P3a on tergites II-VII. It is similar to N. heterothrixi, but differs in absence of seta d6 on the head, shape of accessory setae on tergites VI and VII, long and setiform setaß1, and shorter sensilla c, e, g, a' and c' on the foretarsus than in sensilla in N. heterothrixi and in the porotaxy. A key for the world species of the genus is provided and the porotaxy of five species is reported in detail.


Subject(s)
Arthropods/classification , Animal Distribution , Animal Structures/anatomy & histology , Animal Structures/growth & development , Animals , Arthropods/anatomy & histology , Arthropods/growth & development , Female , Male , Organ Size , Russia
6.
J Colloid Interface Sci ; 647: 1-11, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37236099

ABSTRACT

Design of efficient and durable oxygen reduction reaction (ORR) electrocatalysts still remains challenge in sustainable energy storage and conversion devices. To achieve sustainable development, it is of importance to prepare high-quality carbon-derived ORR catalysts from biomass. Herein, Fe5C2 nanoparticles (NPs) were facilely entrapped in Mn, N, S-codoped carbon nanotubes (Fe5C2/Mn, N, S-CNTs) by a one-step pyrolysis of the mixed lignin, metal precursors and dicyandiamide. The resulting Fe5C2/Mn, N, S-CNTs had open and tubular structures, which exhibited positive shifts in the onset potential (Eonset = 1.04 V) and high half-wave potential (E1/2 = 0.85 V), showing excellent ORR characteristics. Further, the typical catalyst-assembled Zn-air battery showed a high power density (153.19 mW cm-2) and good cycling performance as well as obvious cost advantage. The research provides some valuable insights for rational construction of low-cost and environmentally sustainable ORR catalysts in clean energy field, coupled by offering some valuable insights for reusing biomass wastes.

7.
J Colloid Interface Sci ; 639: 424-433, 2023 Jun.
Article in English | MEDLINE | ID: mdl-36812858

ABSTRACT

Oxygen reduction reaction (ORR) on cathode severely suffers from sluggish kinetics in zinc-air batteries. Therefore, substantial efforts have been made to prepare advanced electrocatalysts for facilitating the ORR. Herein, we synthesized FeCo alloyed nanocrystals entrapped in N-doped graphitic carbon nanotubes on nanosheets (FeCo-N-GCTSs) by 8-aminoquinoline coordination-induced pyrolysis, whose morphology, structures, and property were characterized in details. Impressively, the obtained FeCo-N-GCTSs catalyst showed a positive onset potential (Eonset = 1.06 V) and half-wave potential (E1/2 = 0.88 V), revealing excellent ORR activity. Further, the FeCo-N-GCTSs assembled zinc-air battery displayed the maximum power density of 133 mW cm-2 and negligible gap change in the discharge-charge voltage plot over 288 h (ca. 864 cycles) at 5 mA cm-2, outperforming the Pt/C + RuO2 based counterpart. This work provides a facile route for construction of high-efficiency, durable and low-cost nanocatalysts for the ORR in fuel cells and rechargeable Zn-air batteries.

8.
Ying Yong Sheng Tai Xue Bao ; 33(5): 1405-1412, 2022 May.
Article in Zh | MEDLINE | ID: mdl-35730100

ABSTRACT

A laboratory experiment was conducted to investigate the impacts of freeze-thaw intensity (-5-5 ℃, -10-5 ℃) and frequency (1, 5, 10, 15 times) on the community structure of soil arthropod in permafrost zone, Great Hing'an Mountains with the 5 ℃ as control. A total of 4198 individuals of soil arthropod were extracted, belonging to 4 classes, 9 orders, 24 families and 33 genera. The results showed that the number of individuals and groups of soil arthropod decreased significantly in the treatment with high frost intensity (-10-5 ℃), while the individuals of some taxa increased in the treatment with low frost intensity (-5-5 ℃) after the first freeze-thaw incubation. The group number, Margalef index and Shannon index decreased with the increases of freeze-thaw cycling times in low frost intensity treatment, while did not change regularly in high frost intensity treatment. Larva stage was a kind of survival strategy for arthropod to resist low temperature stress, with Acari showing stronger cold tolerance. Different responses of soil arthropod to freeze-thaw cycles, synergistic effect among species and soil environment were factors affecting the structure of soil arthropod community. This study could provide scientific data and theoretical basis for the research and conservation of soil arthropod diversity in the permafrost zone in mid-high latitudes.


Subject(s)
Arthropods , Permafrost , Animals , China , Freezing , Humans , Soil/chemistry
9.
J Colloid Interface Sci ; 627: 630-639, 2022 Dec.
Article in English | MEDLINE | ID: mdl-35872420

ABSTRACT

It is a challenging task to research oxygen reduction electrocatalysts with cost-effectiveness, high-performance and ultra-stability to replace traditional noble metal catalysts in renewable energy conversion/storage devices. Herein, cobalt phosphide (Co2P) nanoparticles encapsulated in Mn, N co-doped porous carbon nanosheets with abundant nanoholes (Co2P/Mn,N-PCNS) were prepared by a alizarin complexone coordination regulated pyrolysis at 800 °C. In the controlled experiments, the pyrolysis temperature and metal types were investigated in details. The resultant catalyst exhibited rapid mass/charge transfer and superior oxygen reduction reaction (ORR) performance (Eonset = 0.96 V; E1/2 = 0.86 V vs RHE), surpassing commercial Pt/C. This work presents some constructive guidelines for synthesis of appealing ORR electrocatalysts in renewable energy technology.

10.
Front Chem ; 10: 974914, 2022.
Article in English | MEDLINE | ID: mdl-36003620

ABSTRACT

A new dysprosium (III) coordination polymer [Dy(Hm-dobdc) (H2O)2]·H2O (Dy-CP), was hydrothermal synthesized based on 4,6-dioxido-1,3-benzenedicarboxylate (H4m-dobdc) ligand containing carboxyl and phenolic hydroxyl groups. The Dy(III) center adopts an octa-coordinated [DyO8] geometry, which can be described as a twisted square antiprism (D 4d symmetry). Neighboring Dy(III) ions are interconnected by deprotonated Hm-dobdc3- ligand to form the two-dimensional infinite layers, which are further linked to generate three-dimensional structure through abundant hydrogen bonds mediated primarily by coordinated and lattice H2O molecules. Magnetic studies demonstrates that Dy-CP shows the field-induced slow relaxation of magnetization and the energy barrier U eff/k B and relaxation time τ 0 are 35.3 K and 1.31 × 10-6 s, respectively. Following the vehicular mechanism, Dy-CP displays proton conductivity with σ equal to 7.77 × 10-8 S cm-1 at 353 K and 30%RH. Moreover, luminescence spectra reveal that H4m-dobdc can sensitize characteristic luminescence of Dy(III) ion. Herein, good magnetism, proton conduction, and luminescence are simultaneously achieved, and thus, Dy-CP is a potential multifunctional coordination polymer material.

11.
Ann Transl Med ; 9(6): 451, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33850848

ABSTRACT

BACKGROUND: The ophthalmic artery (OA) was first reconstructed using computer software. The structural differences of ophthalmic arteries in non-arteritic anterior ischemic optic neuropathy (NAION) and normal eyes, in addition to hemodynamic alterations, were assessed. METHODS: Thirty-one NAION eyes, 19 uninvolved eyes with NAION, and a control group of 26 healthy eyes were retrospectively included. Computed tomographic angiography data were recorded, and corresponding three-dimensional OA models were constructed. Initial OA and internal carotid artery (ICA) diameters and the angle between them were analyzed. Three different OA models were used to evaluate hemodynamic performance. The statistical relationships between the initial diameters of the OA and ICA and the angle between the OA and ICA were described. RESULTS: OA diameters in NAION eyes were significantly smaller than those in both uninvolved and healthy eyes (P<0.05). There was no significant difference between uninvolved and healthy eyes (P=0.31). The initial ICA diameter and the angle between the OA and ICA did not significantly differ among the three groups. In the three models, the blood flow velocity in the initial ophthalmic arteries of uninvolved eyes was higher than that in the NAION eyes. The mass flows of the right and left ophthalmic arteries, accounting for the ipsilateral ICA in the control model, were 0.57%. However, these values in uninvolved and NAION eyes were 1.36% and 0.25%, respectively. CONCLUSIONS: NAION is associated with a smaller initial OA diameter, which may be related to hypoperfusion. To our knowledge, this is the first pilot study to analyze hemodynamic alterations using OA models.

12.
J Bacteriol ; 192(4): 1020-9, 2010 Feb.
Article in English | MEDLINE | ID: mdl-20008070

ABSTRACT

The widely conserved second messenger cyclic diguanosine monophosphate (c-di-GMP) plays a key role in quorum-sensing (QS)-dependent production of virulence factors in Xanthomonas campestris pv. campestris. The detection of QS diffusible signal factor (DSF) by the sensor RpfC leads to the activation of response regulator RpfG, which activates virulence gene expression by degrading c-di-GMP. Here, we show that a global regulator in the X. campestris pv. campestris QS regulatory pathway, Clp, is a c-di-GMP effector. c-di-GMP specifically binds to Clp with high affinity and induces allosteric conformational changes that abolish the interaction between Clp and its target gene promoter. Clp is similar to the cyclic AMP (cAMP) binding proteins Crp and Vfr and contains a conserved cyclic nucleotide monophosphate (cNMP) binding domain. Using site-directed mutagenesis, we found that the cNMP binding domain of Clp contains a glutamic acid residue (E99) that is essential for c-di-GMP binding. Substituting the residue with serine (E99S) resulted in decreased sensitivity to changes in the intracellular c-di-GMP level and attenuated bacterial virulence. These data establish the direct role of Clp in the response to fluctuating c-di-GMP levels and depict a novel mechanism by which QS links the second messenger with the X. campestris pv. campestris virulence regulon.


Subject(s)
Bacterial Proteins/metabolism , Cyclic GMP/analogs & derivatives , Quorum Sensing , Transcription Factors/metabolism , Virulence Factors/metabolism , Xanthomonas campestris/pathogenicity , Allosteric Regulation , Amino Acid Substitution , Bacterial Proteins/chemistry , Binding Sites/genetics , Cyclic GMP/metabolism , Mutagenesis, Site-Directed , Protein Binding , Protein Structure, Tertiary , Transcription Factors/chemistry , Virulence , Virulence Factors/chemistry , Virulence Factors/genetics , Xanthomonas campestris/chemistry
13.
Yao Xue Xue Bao ; 44(8): 858-62, 2009 Aug.
Article in Zh | MEDLINE | ID: mdl-20055152

ABSTRACT

Long-term potentiation (LTP) is thought as a generative mechanism underlying learning and memory via storing information in central nervous system. Electro-neurophysiological assay for LTP is generally used in screening the drugs that can facilitate learning and memory. By using in vivo LTP technique, isolichenin was found to facilitate LTP induction by a tetanic stimulation (20 pulses/100 Hz) in dentate gyrus. This tetanic stimulation by itself, however, cannot induce LTP. Previous study showed the reagent being able to facilitate LTP-induction, like methanol extract of saffron (MES), usually can antagonize the inhibiting effect of 30% ethanol on LTP induction (30 pulses/60 Hz). Isolichenin may also fall into such kind of drugs. Interestingly, comparatively study showed that isolichenin failed to antagonize the inhibiting effect of 30% ethanol on LTP induction (30 pulses/60 Hz). This result indicates a different unknown mechanism existing in the effect of isolichenin on LTP or memory formation.


Subject(s)
Crocus/chemistry , Dentate Gyrus/drug effects , Long-Term Potentiation/drug effects , Plant Extracts/pharmacology , Polysaccharides/pharmacology , Animals , Dentate Gyrus/physiology , Long-Term Potentiation/physiology , Male , Rats , Rats, Wistar
14.
Zootaxa ; 4472(2): 201-232, 2018 Sep 10.
Article in English | MEDLINE | ID: mdl-30313366

ABSTRACT

The present paper reviews the taxonomic studies of the mite suborder Oribatida in the Russian Far East South and Chinese North-East Territories. At present, 746 species of oribatid mites are registered in China, including 175 species in the soils of Northeast China. In the Russian Far East, there were 605 species of oribatids, including 344 species in the south of the Far East. The fauna of the oribatid mites of the Northeast of China and the south of the Russian Far East has 446 species and subspecies representing 190 genera and 80 families. 72 species of oribatid are common for both territories. The modern fauna of the oribatid mites of the Northeast of China and the south of the Far East was formed as a result of prolonged interaction between the boreal and palaearchaearctic faunas. The oribatid fauna of this region is distinguished by the presence of a large number of endemics, some of which are relics of the late Tertiary time and which can be considered as autochthonous. The checklist includes data from more than 100 locations of this enormous region. In addition, a short climatic and historical review of oribatid mites study is presented.


Subject(s)
Mites , Animals , China , Asia, Eastern , Russia , Soil
15.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 1): m161, 2007 Dec 12.
Article in English | MEDLINE | ID: mdl-21200511

ABSTRACT

The title complex, [Mn(2)(C(8)H(7)O(3))(4)(C(12)H(8)N(2))(2)]·0.5CH(3)OH, is a carboxyl-ate-bridged dinuclear Mn(II) complex with four phenoxy-acetate ions and two 1,10-phenanthroline mol-ecules as ligands. Each of the four phenoxy-acetate anions bridges the pair of Mn atoms. The asymmetric unit is completed by a half-occupancy methanol solvent mol-ecule. Face-to-face π-π stacking inter-actions between the aromatic rings of 1,10-phenanthroline molecules belonging to adjacent Mn(2) complexes, with an inter-planar separation of circa 3.4 Å, and weak C-H⋯O hydrogen bonds connect the dinuclear units into a three-dimensional supra-molecular framework.

16.
Ying Yong Sheng Tai Xue Bao ; 28(12): 3965-3975, 2017 Dec.
Article in Zh | MEDLINE | ID: mdl-29696892

ABSTRACT

Agro-ecosystem is an important component of terrestrial ecosystems and it is one of the key areas of global ecological and environmental studies. A 16 hm2 permanent plot in black soil cropland was built to study the community structure of soil biodiversity in typical black soil region in Northeast China. Pitfall trap was used to investigate the ground-dwelling soil macro-arthropods from August to October 2015 in accordance with the three crop growth stages: whirling stage, silking stage, and milk stage. A total of 5284 ground-dwelling soil macro-arthropods belonging to 47 species were captured sorted into 3 classes, 12 orders, 32 families. 3 dominant groups and 11 common groups were found. Phytophages and Omnivores were dominant groups. The individuals and species numbers of ground-dwelling soil macro-arthropods had significant changes with the vegetative growth period. The maximum values of the Shannon index, Margalef index, Pielou index of soil macro-arthropods all appeared in September, but the maximum dominant index appeared in August. From the variation coefficient (CV) and spatial interpolation of different species, it could be seen that there was heterogeneity in the horizontal direction of the ground-dwelling soil macro-arthropod communities. Regarding the relationships between the ground-dwelling soil macro-arthropod communities and soil environmental factors including soil pH, soil organic matter, total nitrogen and soil water content, the bivariate correlation analysis showed there was no significant correlation between them. Results of canonical correspondence analysis (CCA) further indicated that the dominant and common groups were adaptable to environmental factors and widely distributed in the study area. The results showed that the species richness of ground-dwelling soil macro-arthropods was very high in cropland, and the dynamic of soil arthropod's composition and spatial distribution pattern in diffe-rent crop growth stages were significantly changed. It was indicated that biodiversity plot monitoring of black soil cropland had become important means to solve the formation and maintenance mechanism of soil fauna community through large-scale and long-term investigation.


Subject(s)
Arthropods , Biodiversity , Soil , Animals , China , Crops, Agricultural , Ecosystem
17.
Head Neck ; 38 Suppl 1: E832-6, 2016 04.
Article in English | MEDLINE | ID: mdl-25917188

ABSTRACT

BACKGROUND: To achieve an ideal intraoral lining, we harvest the fibular osteomyofascial flap to avoid the common embarrassment caused by the fibular osteomyocutaneous flap, and we report on our experience with this technique in this article. METHODS: Twenty-eight patients underwent reconstruction of the maxilla and mandible using an osteomyofascial free fibula flap after oncologic ablation. Data, including the size of the fascial flaps, the number of debulking operations, the complications at both the donor and recipient sites, and the dental rehabilitation, were collected. RESULTS: All fascial flaps survived and were remucosalized, except one with partial necrosis. None of the patients in the osteomyofascial group required an additional debulking operation, and 82% of the patients (23 of 28) had conventional dentures and showed good chewing function and cosmetic results. CONCLUSION: The fibular osteomyofascial flap yielded a more anatomic solution for oral mucosal defects, obviating the need for additional debulking and potentially reducing donor-site wound problems. © 2015 Wiley Periodicals, Inc. Head Neck 38: E832-E836, 2016.


Subject(s)
Bone Transplantation , Free Tissue Flaps/transplantation , Mandibular Reconstruction , Plastic Surgery Procedures , Adult , Aged , Female , Fibula/transplantation , Humans , Male , Mandible/surgery , Maxilla/surgery , Middle Aged , Mouth Neoplasms/surgery
18.
Eur J Pharmacol ; 723: 259-66, 2014 Jan 15.
Article in English | MEDLINE | ID: mdl-24291097

ABSTRACT

7-Hydroxy-5-methoxy-4-methyl-3-(4-methylpiperazin-1-yl)-coumarin (IMM-H004) is a novel coumarin derivative synthesized in our laboratory. The purpose of the current study was to determine the neuroprotective effects of IMM-H004 on PC12 cells and its potential mechanism of action. PC12 cells were subject to oxygen and glucose deprivation (OGD) followed by the restoration of oxygen and glucose (R), which mimics ischemia and reperfusion in vivo. Cell viability was determined by MTT assay. DNA fragmentation was analyzed by DNA ladder. ROS and mitochondrial membrane potential were measured by fluorescent microscope and quantified by Image-Pro Express 6.0 software. ATP was measured by luciferin-luciferase assay. The activation of signal-regulated molecules was assessed by the Western blot analysis. OH formation was determined using the Electron Spin Resonance (ESR) trapping technique in combination with 5, 5-dimethyl-1-pyrroline-N-oxide. OGD/R reduced cell viability and induced cell apoptosis, which were both dose-dependently attenuated by IMM-H004. The accumulation of intracellular reactive oxygen species (ROS) and reduced mitochondrial membrane potential observed in PC12 cells treated with OGD/R, which switch on the mitochondrion-dependent apoptotic pathway, were reversed by IMM-H004. ATP production in OGD/R-treated PC12 cells was elevated by IMM-H004, which suggests that it restored the functions of the mitochondria. OGD/R-induced cytochrome c release from the mitochondria reduced the ratio of apoptotic proteins, Bcl-2/Bax, and induced caspase-3 activation and DNA fragmentation. These changes were significantly inhibited by IMM-H004. IMM-H004 also significantly inhibited OH formation, determined by electron spin resonance, which indicates that it is a potent free-radical scavenger. This study has demonstrated that IMM-H004 protects PC12 cells against OGD/R-induced apoptosis, at least in part, by scavenging excessive ROS and inhibiting the mitochondrion-dependent apoptotic pathway.


Subject(s)
Apoptosis/drug effects , Coumarins/pharmacology , Glucose/deficiency , Neuroprotective Agents/pharmacology , Adenosine Triphosphate/metabolism , Animals , Cell Hypoxia/physiology , Cell Survival/drug effects , DNA Fragmentation , Membrane Potential, Mitochondrial/drug effects , PC12 Cells , Proto-Oncogene Proteins c-bcl-2/metabolism , Rats , Reactive Oxygen Species/metabolism , bcl-2-Associated X Protein/metabolism
19.
Ying Yong Sheng Tai Xue Bao ; 23(12): 3526-32, 2012 Dec.
Article in Zh | MEDLINE | ID: mdl-23479899

ABSTRACT

Low temperature and drought are the main environmental factors threatening the animals living in arctic area and cold temperate regions. To adapt the severe environment, the animals should adopt appropriate strategies. As a group of arthopods with freeze-avoiding strategy, soil springtails have the similar ecological mechanisms and modes of cold resistance/tolerance as insects, manifesting in the cold acclimation and drought tolerance to decrease the damage of ice crystal formation. During cold acclimation, there are a rapid increase of glycerol, a rapid decrease of fucose and glucose, and the production of anti-freeze proteins (AFP) , and exists the inter-transformation of different kinds of lipids to improve the flow of cell membrane to protect the cell from low temperature injury. In addition, soil springtails have their own specific modes and mechanisms to tolerate low temperature stress, mainly the vertical migration under the protection of snow cover and the excretion of ice nucleator from haemolymph, illustrating that it's of significance to research the cryobiology of soil springtails. This paper summarized the modes and mechanisms of soil springtails in tolerating low temperature environment, reviewed the research progress on the eco-physiology of the springtails, discussed the existing problems of the researches on the low temperature tolerance of the springtails, and prospected the research directions of the springtails low temperature ecology under the background of global change.


Subject(s)
Acclimatization/physiology , Arthropods/physiology , Cold Temperature , Soil/parasitology , Animals , Climate Change , Environment
20.
Article in Zh | WPRIM | ID: wpr-823268

ABSTRACT

Objective@#To evaluate the effect of palatal free gingiva in anterior maxillary defect restoration after epulis resection. @*Methods@# 22 cases were included in this study. Palatal free gingival flap was prepared to restore anterior maxillary defect after epulis resection. Clinical effect was evaluated according to gingival margin, gingival papilla index and modified sulcus bleeding index. @*Results @#Satisfactory clinical effect was achieved in all 22 cases, with adequate height, thickness, fullness and texture. @*Conclusin @#Palatal free gingival flap was clinically effective in anterior maxillary defect treatment after epulis resection, with satisfactory aesthetic clinical effect.

SELECTION OF CITATIONS
SEARCH DETAIL