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1.
Adv Mater ; : e2402234, 2024 May 23.
Article in English | MEDLINE | ID: mdl-38781597

ABSTRACT

Rationally designed defects in a crystal can confer unique properties. This study showcases a novel dual-defects engineering strategy to tailor the electrochemical response of metal-organic framework (MOF) materials used for electrochemical energy storage. Salicylic acid (SA) is identified as an effective modulator to control MOF-74 growth and induce structural defects, and cobalt cation doping is adopted for introducing a second type of defect. The resulting dual-defects engineered bimetallic MOF exhibits a discharging capacity of 218.6 mAh g-1, 4.4 times that of the pristine MOF-74, and significantly improved cycling stability. Moreover, the engineered MOF-74(Ni0.675Co0.325)-8//Zn aqueous battery shows top energy/power density performances for Ni-Zn batteries (266.5 Wh kg-1, 17.22 kW kg-1). Comprehensive investigations reveal that engineered defects modify the local coordination environment and promote the in situ electrochemical reconfiguration during operation to significantly boost the electrochemical activity. This work suggests that rational tailoring of the defects within the MOF crystal is an effective strategy to manipulate the coordination environment of the metal centers and the corresponding electrochemical reconfiguration for electrochemical applications.

2.
Rev Sci Instrum ; 95(3)2024 Mar 01.
Article in English | MEDLINE | ID: mdl-38466030

ABSTRACT

Heat capacity is a fundamental thermodynamic property of a substance. Although heat capacity values and related thermodynamic functions are available for many materials, low-temperature heat capacity measurements, especially for novel materials, can still provide valuable insights for research in physics, chemistry, thermodynamics, and other fields. Reliable low-temperature heat capacity data are typically measured using classical adiabatic calorimeters, which use liquid helium as the refrigerant to provide a cryogenic environment for heat capacity measurements. However, liquid helium is not only expensive but also not easy to obtain, which greatly limits the application of adiabatic calorimetry. In this work, an accurate adiabatic calorimeter equipped with a Gifford-MacMahon refrigerator was designed and constructed for measuring the heat capacity of condensed matter in the temperature range from 4 to 100 K. The Gifford-MacMahon refrigerator was utilized to provide a stable liquid helium-free cryogenic environment. A simple mechanical thermal switch assembly was designed to facilitate switching between the refrigeration mode and the adiabatic measurement mode of the calorimeter. Based on the measurement results of standard reference materials, the optimized repeatability and accuracy of heat capacity measurements were determined to be within 0.8% and 1.5%, respectively. The heat capacity of α-Fe2O3 nanoparticles was also investigated with this device. Furthermore, this adiabatic calorimeter only requires electricity to operate in the liquid helium temperature range, which may significantly advance the research on low-temperature heat capacity based on adiabatic calorimetry.

3.
Immun Inflamm Dis ; 11(11): e1074, 2023 Nov.
Article in English | MEDLINE | ID: mdl-38018581

ABSTRACT

BACKGROUND: Rapidly progressive glomerulonephritis (RPGN) is clinically manifestations as a rapidly progressive renal failure and pathologically as crescentic and necrotizing lesions with infiltration of inflammatory cells in the glomeruli. Uremic encephalopathy (UE) usually develops in patients who are suffering from acute or chronic renal failure. OBJECTIVE: The purpose of this article is to provide reference for clinical diagnosis and treatment of renal disease complicated with seizures. Patients Two cases of anti-glomerular basement membrane type rapidly progressive glomerulonephritis complicated with seizures were reported. MATERIALS & METHODS: In case 1, a 40-year-old woman was hospitalized for the treatment of nausea, anorexia, and fever. On admission, she presented with elevated serum inflammatory indicators, moderate anemia, and advanced acute kidney injury requiring hemodialysis. Her anti-glomerular basement membrane (GBM) antibody in serum and renal tissues was found to be extremely high. She was finally diagnosed with anti-GBM disease. She was treated with a combination of corticosteroid pulse therapy, oral cyclophosphamide and prednisolone, and plasma exchange, while continued to require maintenance hemodialysis for end-stage kidney disease. During treatment, she suddenly suffered blindness, seizure, and consciousness disturbance. She was diagnosed as posterior reversible leukoencephalopathy syndrome by magnetic resonance imaging (MRI). The posterior reversible leukoencephalopathy syndrome subsided quickly after control of her hypertension and reinforcement of immunosuppressive treatment. In case 2, the patient also developed epileptic symptoms on the basis of GBM disease, and was given treatment similar to that of Case 1, so that the epileptic symptoms were controlled. RESULT: Reversible posterior leukoencephalopathy syndrome, especially when accompanied by cerebral hemorrhage, may lead to irreversible and lethal neurological abnormalities, and nephrologists should, therefore, be aware of the potential risk of reversible posterior leukoencephalopathy syndrome in patients with anti-GBM disease. We can discuss the current two cases in the light of the previous literature.


Subject(s)
Anti-Glomerular Basement Membrane Disease , Glomerulonephritis , Posterior Leukoencephalopathy Syndrome , Humans , Female , Adult , Anti-Glomerular Basement Membrane Disease/complications , Anti-Glomerular Basement Membrane Disease/diagnosis , Anti-Glomerular Basement Membrane Disease/therapy , Posterior Leukoencephalopathy Syndrome/complications , Posterior Leukoencephalopathy Syndrome/diagnosis , Glomerulonephritis/complications , Glomerulonephritis/diagnosis , Glomerulonephritis/therapy , Seizures/complications
4.
Sci Rep ; 13(1): 6828, 2023 04 26.
Article in English | MEDLINE | ID: mdl-37100857

ABSTRACT

Dietary restriction (DR) has been a very important discovery in modern aging biology research. Its remarkable anti-aging effect has been proved in a variety of organisms, including members of Lepidoptera, but mechanisms by which DR increases longevity are not fully understood. By using the silkworm (Bombyx mori), a model of lepidopteran insect, we established a DR model, isolated hemolymph from fifth instar larvae and employed LC-MS/MS metabolomics to analyze the effect of DR on the endogenous metabolites of silkworm, and tried to clarify the mechanism of DR to prolong lifespan. We identified the potential biomarkers by analyzing the metabolites of the DR and control groups. Then, we constructed relevant metabolic pathways and networks with MetaboAnalyst. DR significantly prolonged the lifespan of silkworm. The differential metabolites between the DR and control groups were mainly organic acids (including amino acid), and amines. These metabolites are involved in metabolic pathways such as amino acid metabolism. Further analysis showed that, the levels of 17 amino acids were significantly changed in the DR group, indicating that the prolonged lifespan was mainly due to changes in amino acid metabolism. Furthermore, we identified 41 and 28 unique differential metabolites in males and females, respectively, demonstrating sex differences in biological responses to DR. The DR group showed higher antioxidant capacity and lower lipid peroxidation and inflammatory precursors, with differences between the sexes. These results provide evidence for various DR anti-aging mechanisms at the metabolic level and novel reference for the future development of DR-simulating drugs or foods.


Subject(s)
Bombyx , Animals , Female , Male , Bombyx/metabolism , Larva , Longevity , Amino Acids/metabolism , Hemolymph/metabolism , Chromatography, Liquid , Tandem Mass Spectrometry
5.
Food Chem Toxicol ; 148: 111971, 2021 Feb.
Article in English | MEDLINE | ID: mdl-33421460

ABSTRACT

The present study presented the extraction and purification of polysaccharides from artificially cultured Cordyceps cicadae and wild Cordyceps cicadae by pre-soaking ultrasonic water extraction. The effects of different concentrations of polysaccharides on proliferation and cytotoxicity of Hela cells were detected by MTT and LDH methods. The results showed that the proliferation of Hela cells was inhibited by polysaccharides treatment (25 µg/mL-1600 µg/mL). The results of flow cytometry further confirmed that polysaccharides blocked the cell cycle in the S phase and promoted apoptosis. RT-qPCR and Western Blot were used to study the mRNA and protein expression of genes related to cell cycle and apoptosis signaling pathway. The results showed that polysaccharides treatment inhibited the expression of Cyclin E, Cyclin A and CDK2 and up regulated the expression of P53. Further, activation of Caspase cascade reaction, up regulation of death receptor, and the ratio of pro-apoptotic factor/anti-apoptotic factors, thus caused the cell cycle arrest and induced the apoptosis. The above research results lay a foundation for extending the anti-cancer effects of natural plant resources with low toxicity and high efficiency.


Subject(s)
Antineoplastic Agents/pharmacology , Apoptosis/drug effects , Cell Proliferation/drug effects , Cordyceps/chemistry , Polysaccharides/pharmacology , S Phase Cell Cycle Checkpoints/drug effects , Antineoplastic Agents/isolation & purification , Drug Screening Assays, Antitumor , Gene Expression Regulation, Neoplastic/drug effects , HeLa Cells , Humans , Mitochondria/metabolism , Polysaccharides/isolation & purification
6.
J Cell Biochem ; 120(9): 14326-14335, 2019 09.
Article in English | MEDLINE | ID: mdl-31106458

ABSTRACT

MicroRNAs (miRs) are inner regulatory RNAs mainly by regulating expression of genes at the posttranscriptional level. To investigate the regulatory function of Bombyx mori (B. mori) fibroin protein genes, the mRNA 3'-untranslated region (3'-UTR) of fibroin light chain gene (BmFib-L) was used as the target and one miRNA, miR-2805 was predicted by using the Software. miR-2805 expression plasmid pcDNA3.0[ie1-egfp-pre-miR-2805-SV40] and BmFib-L 3'-UTR plasmid pGL3.0[A3-luc-Fib-L-3'-UTR-SV40] were constructed, respectively. The mentioned plasmids were cotransfected in BmN cells, and the regulatory function of miR-2805 on BmFib-L was detected by assay of dual luciferase activities, as well as synthesized mimic and inhibitor of miR-2805. The results revealed that miR-2805 significantly downregulated the expression of BmFib-L in BmN cells. To validate the function of miR-2805 in vivo, cultured silk glands or larvae were injected with solution containing pcDNA3.0[ie1-egfp-SV40], pcDNA3.0[ie1-egfp-pre-miR-2805-SV40], mimic, inhibitor respectively. BmFib-L expression was analyzed by quantitative reverse transcription polymerase chain reaction using total RNAs extracted from silk glands. The results showed that miR-2805 significantly upregulated the expression of BmFib-L in both cultured tissues and individuals. To find out how miR-2805 differentially regulates BmFib-L expression in cells and tissues or individuals, we analyzed the expression level of transcription factors (TFs) involved in expression of silk protein genes. The results showed that miR-2805 upregulated the expression of TFs BmAwh and Bmdimm. These results suggest that miR-2805 may up-regulate the expression of BmFib-L interaction with BmAwh and/or Bmdimm in vivo. These findings are beneficial to clarify the molecular mechanism of miRNAs in regulating B. mori silk protein biosynthesis.


Subject(s)
3' Untranslated Regions/genetics , Bombyx/genetics , Fibroins/genetics , Gene Expression Regulation , MicroRNAs/genetics , Animals , Base Sequence , Bombyx/cytology , Bombyx/metabolism , Cell Line , Fibroins/metabolism , Gene Expression Profiling/methods , Insect Proteins/genetics , Insect Proteins/metabolism , Larva/genetics , Transcription Factors/genetics , Transcription Factors/metabolism
7.
Article in English | MEDLINE | ID: mdl-28850878

ABSTRACT

In the bivoltine strain of the silkworm, Bombyx mori, embryonic diapause is induced transgenerationally as a maternal effect. Progeny diapause ability is determined by the environmental condition such as temperature and lightness that mothers experience during their own embryonic development. Diapause preparation is a crucial phase of this process; diapause-destined individuals undergo a series of preparatory events before the entry into developmental arrest. However, the molecular regulatory mechanisms of diapause preparation have largely remained unknown. In the present study, we sequenced the transcriptome of bivoltine silkworm Qiufeng's ovaries resulted in laying of diapause destined or non-diapause eggs, using high-throughput RNA-Seq technology. Differential expression analyses identified 183 genes with higher expression, and 106 with lower expression under diapause-inducing conditions. GO and KEGG analysis revealed that the enrichment of several functional terms related to peroxisome, glycerolipid metabolism, steroid biosynthesis, longevity regulating pathway - multiple species, three signaling transductions, insect hormone biosynthesis, and cytoskeleton components. We conducted a detailed comparison of transcript profile data of ovaries from diapause-inducing and non-diapause conditions, the results imply up-regulation of peroxisomal metabolism, triacylglycerides accumulation, cryoprotectant production, and ecdysteroid biosynthesis in diapause-inducing group. Differential expression of genes related to actin cytoskeleton implies the occurrence of shifts in cellular structure and composition between diapause-inducing and non-diapause-inducing groups. The Hippo and FOXO signaling pathways may play an important role in preparing for entering diapause. This study provides an insight into the molecular events of insect diapause, in particular for the preparatory phase.


Subject(s)
Bombyx/genetics , Diapause, Insect/genetics , Gene Expression Profiling/methods , Sequence Analysis, RNA/methods , Transcriptome/genetics , Animals , Female , Gene Expression Regulation, Developmental/genetics , RNA, Messenger/analysis , RNA, Messenger/genetics , RNA, Messenger/metabolism , Signal Transduction
8.
Int J Clin Exp Med ; 8(2): 2966-73, 2015.
Article in English | MEDLINE | ID: mdl-25932265

ABSTRACT

Renal involvement is a significant complication of multicentric Castleman's disease (MCD) and various glomerular involvements have been reported. A 56-year-old Chinese woman presented with proteinuria and skin rash, with lymphadenopathy and hypergammaglobulinemia. Lymph nodes and skin biopsy proven the case was multicentric CD with plasma cell pathological pattern. The renal biopsy was performed and six glomeruli were observed and two of these showed global sclerosis. Moderate increasing of mesangial matrix with mesangial cell proliferation were seen in every glomerulus. In addition, one-segmental sclerosis accompanied by adhesion of the Bowman's capsule was revealed. Two of the glomeruli had crescents formation. Under immunofluorescence microscopy, immunofluorescence for anti-IgA, IgM, C3, C1q and FRA showed coarse and fine granular depositions along capillary walls and sparsely in the mesangium. Staining for anti-IgG was negative. Under electron microscopy revealed indiscriminate amyloidal deposits in glomerular basement membrane. The foot process of glomerular podocytes was fusion. Moderate increasing of mesangial matrix and mesangial cell proliferation were found. Subsequently, she was successfully treated with prednisone combined with cyclophosphamide therapy not only for proteinuria but also for renal function.

9.
Ren Fail ; 37(4): 727-33, 2015 May.
Article in English | MEDLINE | ID: mdl-25697231

ABSTRACT

In this study, we investigated the impact of endogenous hydrogen sulfide (H2S) on toll-like receptors (TLRs)-mediated inflammatory response and apoptosis in renal ischemia-reperfusion injury (IRI). Twenty-four male Wistar rats were randomly divided into four groups: sham, IR, IR + propargylglycine (PAG) and IR + hydroxylamine (HA). After right nephrectomy, rats were given saline for the sham and IR group, PAG for the IR + PAG group and HA for the IR + HA group, through the left renal artery for 20 min. Five minutes after drug administration, all rats except sham underwent 45 min of left renal ischemia followed by 24 h of reperfusion. Kidneys were harvested for histological and biochemical evaluation. Levels of TLRs, downstream signaling molecules and pro-inflammatory cytokines were determined by Western blot or immunohistochemistry. Hematoxylin and eosin (H&E) stained renal sections were used for histological grading of renal injury. Apoptotic cells were detected by TUNEL assay. Compared to the sham group, rats in the IR group showed higher renal levels of TLR-2, TLR-4, nuclear NF-κB p65, phosphorylated ASK1, phosphorylated TRAF2, IL-1ß, IL-6, IL-18 and TNF-α (p < 0.05), and exhibited acute kidney injury (p < 0.05) and apoptosis (p < 0.05). Compared to the IR group, rats receiving PAG or HA showed significantly higher levels of TLR-2, TLR-4, nuclear NF-κB p65, phosphorylated ASK1, phosphorylated TRAF2, IL-1ß, IL-6, IL-18 and TNF-α (p < 0.01), more severe acute kidney injury (p < 0.05) and increased apoptosis (p < 0.01). Thus, inflammatory response and apoptosis mediated by TLRs are involved in renal IRI. Inhibition of endogenous H2S significantly activated inflammatory response and apoptosis, and thus promoted renal IRI.


Subject(s)
Hydrogen Sulfide , Kidney/blood supply , Reperfusion Injury/physiopathology , Signal Transduction , Toll-Like Receptors/physiology , Animals , Male , Random Allocation , Rats , Rats, Wistar
10.
Phys Chem Chem Phys ; 13(1): 199-206, 2011 Jan 07.
Article in English | MEDLINE | ID: mdl-21103581

ABSTRACT

Two chelated orthoborate ionic liquids (ILs), 1-butyl-3-methylimidazolium bis(oxalato)borate ([Bmim][BOB]) and 1-hexyl-3-methylimidazolium bis(oxalato)borate ([Hmim][BOB]), were prepared and characterized. Their thermodynamic properties were studied using adiabatic calorimetry and differential scanning calorimetry (DSC). The thermodynamic properties of the two ILs were evaluated and compared with each other, and then with those of other [Bmim] type ILs. The results clearly indicate that for a given cation (or anion) and at a certain temperature, the more atoms in the anion (or cation), the higher the heat capacity; the higher glass-transition temperatures of [BOB] type ILs than others are mainly caused by the higher symmetry of the orthoborate anion structure. It is suggested that a high content of strong electronegative atoms and C(n) or C(nv) (n = 1,2,3,…,∞) point group symmetry in the anion are favorable for the design and synthesis of room temperature ILs with a wide liquid range.


Subject(s)
Borates/chemistry , Ionic Liquids/chemistry , Thermodynamics , Anions/chemistry , Borates/chemical synthesis , Calorimetry , Ionic Liquids/chemical synthesis , Molecular Structure
11.
J Phys Chem A ; 114(11): 3782-7, 2010 Mar 25.
Article in English | MEDLINE | ID: mdl-20235601

ABSTRACT

Two ionic liquids, 1-ethylpyridinium bromide (EPBr) and 1-propylpyridinium bromide (PPBr), were prepared and the structures were characterized by 1H NMR. The thermodynamic properties of EPBr and PPBr were studied with adiabatic calorimetry (AC) and thermogravimatric analysis (TG-DTG). The heat capacity was precisely measured in the temperature range from 78 to 410 K by means of a fully automated adiabatic calorimeter. For EPBr, the melting temperature, enthalpy, and entropy of solid-liquid phase transition were determined to be 391.31 +/- 0.28 K, 12.77 +/- 0.09 kJ x mol(-1), and 32.63 +/- 0.22 J x K(-1) x mol(-1), respectively, and for PPBr they were 342.83 +/- 0.69 K, 10.97 +/- 0.05 kJ x mol(-1), and 32.00 +/- 0.10 J x K(-1) x mol(-1), respectively. The thermodynamic functions (H(T)(0) - H(298.15)(0)) and (S(T)(0) - S(298.15)(0)) were derived from the heat capacity data in the experimental temperature range with an interval of 5 K. The thermostablility of the compounds was further studied by TGA measurements. The phase change behavior and thermodynamic properties were compared and estimated in a series of alkyl pyridinium bromide ionic liquids. Results indicate that EPBr has higher melting and decomposition temperature, as well as phase transition enthalpy and entropy but lower heat capacity than PPBr due to their different molecular structures.

12.
Acta Chim Slov ; 57(2): 370-85, 2010 Jun.
Article in English | MEDLINE | ID: mdl-24061733

ABSTRACT

Low-temperature heat capacities of 2-pyrazinecarboxylic acid (C5H4N2O2)(s) were measured by a precision automated adiabatic calorimeter over the temperature range from 78 to 400 K. A polynomial equation of heat capacities as a function of temperature was fitted by least squares method. Based on the fitted polynomial, the smoothed heat capacities and thermodynamic functions of the compound relative to the standard reference temperature 298.15 K were calculated and tabulated at 10 K intervals. The constant-volume energy of combustion of the compound at T = 298.15 K was measured by a precision rotating-bomb combustion calorimeter to be ΔcU = -(17839.40 ± 7.40) J g-1. The standard molar enthalpy of combustion of the compound was determined to be ΔcH0m = -(2211.39 ± 0.92) KJ mol-1, according to the definition of combustion enthalpy. Finally, the standard molar enthalpy of formation of the compound was calculated to be ΔfH0m = -(327.82 ± 1.13) kJ mol-1 in accordance with Hess law.

13.
Biol Pharm Bull ; 25(2): 165-7, 2002 Feb.
Article in English | MEDLINE | ID: mdl-11853158

ABSTRACT

In this paper, a poly(vinyl chloride) (PVC) membrane electrode is prepared for gemfibrozil, 2, 2-dimethyl-5-(2,5-xylyloxy) valeric acid, based on its ion pair complexes with hexadecyltrioctyl ammonium iodide (HTOA). The membrane composition of the electrode was optimized by using the sequential level elimination method for orthogonal experimental design. The electrode has a Nernstian response range from 2.5 x 10(-5) to 0.1 mol/l with an average slope of 55.3 mV/decade. The limit of detection is 7.1 x 10(-6) mol/l. The electrode responses were not affected by pH in the range 10.0-12.3. A Na2B4O7-Na2CO3 buffer of pH = 11.0 was selected as the background electrolyte solution for potentiometric measurements. The electrode was used for determining gemfibrozil in pharmaceutical preparations with satisfactory results.


Subject(s)
Gemfibrozil/analysis , Hypolipidemic Agents/analysis , Electrodes , Hydrogen-Ion Concentration , Polyvinyl Chloride , Potentiometry , Reproducibility of Results
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