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1.
ACS Nano ; 18(27): 17950-17957, 2024 Jul 09.
Article in English | MEDLINE | ID: mdl-38916519

ABSTRACT

The pursuit of high energy density in lithium batteries has driven the development of efficient electrodes with low levels of inactive components. Herein, a facile approach involving the use of π-π stacked nigrosine@carbon nanotube nanocomposites as an all-in-one additive for a LiFePO4 cathode has been developed. This design significantly reduces the proportion of inactive substances within the cathode, resulting in a battery that exhibits a high specific capacity of 143 mAh g-1 at a 1 C rate and shows commendable cyclic performance. Furthermore, the elimination of rigid current collectors endows the electrode with flexibility, offering avenues for future wearable energy storage devices.

2.
Angew Chem Int Ed Engl ; 63(20): e202402910, 2024 May 13.
Article in English | MEDLINE | ID: mdl-38441480

ABSTRACT

The challenge of constructing a mechanically robust yet lightweight artificial solid-electrolyte interphase layer on lithium (Li) anodes highlights a trade-off between high battery safety and high energy density. Inspired by the intricate microstructure of the white sea urchin, we first develop a polyvinyl fluoride-hexafluoropropylene (PVDF-HFP) interfacial layer with a triple periodic minimal surface structure (TPMS) that could offer maximal modulus with minimal weight. This design endows high mechanical strength to an ordered porous structure, effectively reduces local current density, polarization, and internal resistance, and stabilizes the anode interface. At a low N/P ratio of ~3, using LiFePO4 as the cathode, Li anodes protected by TPMS-structured PVDF-HFP achieve an extremely low capacity-fading-rate of approximately 0.002 % per cycle over 200 cycles at 1 C, with an average discharge capacity of 142 mAh g-1. Meanwhile, the TPMS porous structure saves 50 wt % of the interfacial layer mass, thereby enhancing the energy density of the battery. The TPMS structure is conducive to large-scale additive manufacturing, which will provide a reference for the future development of lightweight, high-energy-density secondary batteries.

3.
J Biol Chem ; 299(11): 105274, 2023 11.
Article in English | MEDLINE | ID: mdl-37739037

ABSTRACT

Endoplasmic reticulum (ER)-associated degradation (ERAD) is a protein quality control process that eliminates misfolded proteins from the ER. DnaJ homolog subfamily C member 10 (ERdj5) is a protein disulfide isomerase family member that accelerates ERAD by reducing disulfide bonds of aberrant proteins with the help of an ER-resident chaperone BiP. However, the detailed mechanisms by which ERdj5 acts in concert with BiP are poorly understood. In this study, we reconstituted an in vitro system that monitors ERdj5-mediated reduction of disulfide-linked J-chain oligomers, known to be physiological ERAD substrates. Biochemical analyses using purified proteins revealed that J-chain oligomers were reduced to monomers by ERdj5 in a stepwise manner via trimeric and dimeric intermediates, and BiP synergistically enhanced this action in an ATP-dependent manner. Single-molecule observations of ERdj5-catalyzed J-chain disaggregation using high-speed atomic force microscopy, demonstrated the stochastic release of small J-chain oligomers through repeated actions of ERdj5 on peripheral and flexible regions of large J-chain aggregates. Using systematic mutational analyses, ERAD substrate disaggregation mediated by ERdj5 and BiP was dissected at the molecular level.


Subject(s)
Endoplasmic Reticulum Chaperone BiP , Endoplasmic Reticulum-Associated Degradation , Molecular Chaperones , Endoplasmic Reticulum Chaperone BiP/chemistry , Endoplasmic Reticulum Chaperone BiP/genetics , Endoplasmic Reticulum Chaperone BiP/metabolism , Molecular Chaperones/chemistry , Molecular Chaperones/genetics , Molecular Chaperones/metabolism , Protein Folding , HEK293 Cells , Immunoglobulin J-Chains/metabolism , Protein Domains
4.
Cell Rep ; 41(10): 111760, 2022 12 06.
Article in English | MEDLINE | ID: mdl-36476867

ABSTRACT

Sarco/endoplasmic reticulum Ca2+ ATPase (SERCA) pumps Ca2+ into the endoplasmic reticulum (ER). Herein, we present cryo-electron microscopy (EM) structures of three intermediates of SERCA2b: Ca2+-bound phosphorylated (E1P·2Ca2+) and Ca2+-unbound dephosphorylated (E2·Pi) intermediates and another between the E2P and E2·Pi states. Our cryo-EM analysis demonstrates that the E1P·2Ca2+ state exists in low abundance and preferentially transitions to an E2P-like structure by releasing Ca2+ and that the Ca2+ release gate subsequently undergoes stepwise closure during the dephosphorylation processes. Importantly, each intermediate adopts multiple sub-state structures including those like the next one in the catalytic series, indicating conformational overlap at transition steps, as further substantiated by atomistic molecular dynamic simulations of SERCA2b in a lipid bilayer. The present findings provide insight into how enzymes accelerate catalytic cycles.


Subject(s)
Cryoelectron Microscopy
5.
BMC Musculoskelet Disord ; 22(1): 112, 2021 Jan 26.
Article in English | MEDLINE | ID: mdl-33499842

ABSTRACT

BACKGROUND: Carpal tunnel syndrome (CTS) is the most common entrapment symptom in the peripheral nerves. High-frequency ultrasound (HFUS) is widely used in the diagnosis of CTS. Virtual Touch Tissue Imaging and Quantification (VTIQ), which provides more information about the hardness of organization, is used to diagnose CTS. However, the data of diagnostic value of them in various degrees of CTS are limited. Whether the combination of HFUS and VTIQ can improve the diagnostic efficiency also remains unknown. The study aimed to explore the diagnostic value of HFUS and VTIQ in various degrees of CTS and whether combination of HFUS and VTIQ could improve the diagnostic efficiency of CTS. METHODS: A collection and analysis of 133 CTS patients and 35 volunteers from January 2016 to January 2019 were performed. We compared the clinical characteristics, cross-sectional area (CSA) value and shear wave velocity SWVmean value of CTS group with volunteer group. RESULTS: The CSA value and SWVmean value of CTS cohort were significantly higher than volunteer group (10.79 ± 2.88 vs. 8.06 ± 1.39, p < 0.001, 4.36 ± 0.95 vs. 3.38 ± 1.09, p < 0.001, respectively). The area under the curve (AUC) of receiver operating characteristic (ROC) curve of CSA value and SWVmean value were 0.794 and 0.757, respectively. Hierarchical analysis of CSA value and SWVmean value showed that the AUC in the moderate and severe CTS group were higher than in mild CTS group. Furthermore, the CSA value combined with SWVmean value used to diagnose mild CTS was 0.758, which was higher than that of single CSA value or single SWVmean value. CONCLUSIONS: Both HFUS and VTIQ technology were feasible to evaluate CTS. HFUS was suitable for use in diagnosis of moderate and severe CTS. For mild CTS, combination of HFUS and VTIQ was relevant to improve the diagnostic efficiency of CTS.


Subject(s)
Carpal Tunnel Syndrome , Area Under Curve , Carpal Tunnel Syndrome/diagnostic imaging , Diagnostic Tests, Routine , Humans , Median Nerve/diagnostic imaging , ROC Curve , Sensitivity and Specificity , Ultrasonography
6.
Bioanalysis ; 11(20): 1823-1834, 2019 Oct.
Article in English | MEDLINE | ID: mdl-31657231

ABSTRACT

Aim: Contract research organizations and pharmaceutical firms have performed stability testing using one of two methods: storing in the freezer a single tube of matrix for each quality control concentration (Method 1), followed by aliquoting and analysis; and storing three tubes for each quality control concentration, followed by analysis (Method 2). This research project was conducted to determine if there were detectable differences between Method 1 and Method 2. Methodology: Five model drugs were selected: teriflunomide (stable compound) and acetyl salicylic acid, simvastatin, tenofovir alafenamide and valganciclovir (stability concerns). Samples were stored at -80°C for 1, 3 and 12 months and then analyzed. Samples were also placed at different locations within the freezer. Results: For the drugs tested, the results suggest that there is no significant difference in the outcome of stability testing, regardless whether Method 1 or Method 2 was followed.


Subject(s)
Chemistry Techniques, Analytical/methods , Drug Storage , Pharmaceutical Preparations/analysis , Quality Control
7.
Int J Clin Exp Med ; 8(11): 20056-64, 2015.
Article in English | MEDLINE | ID: mdl-26884917

ABSTRACT

OBJECTIVE: To investigate diagnostic value of ultrasonography scores (US) and contrast-enhanced ultrasonography (CEUS) in evaluating rheumatoid arthritis (RA) activity. METHODS: 39 patients with RA were included and the metacarpophalangeal, proximal interphalangeal, wrist, elbow and knee joints of them were examined by high frequency ultrasound. The severe joints and the related indexes (synovial thickness, synovial blood flow, joint effusion and bone erosion) were exposed. Then scores (0~3) were obtained and the sum was calculated. For 12 patients of the 39, 2.4 ml SonoVue was intravenously injected with observation of synovial enhancing. ROIs time-intensity curve (TIC) was obtained and the parameters including area under curve (AUC), peak intensity (PI) and time to peak (TTP) were analyzed. For 39 patients, the relationships among each parameters, ultrasonography scores, DAS28 scores and biochemical examinations (ESR, CRP, RF, anti-CCP) were analyzed. RESULTS: The US were significantly correlated with DAS28 Scores (r=0.823, P<0.01=. The correlation between US and CRP was better than that between DAS28 scores and CRP (rUS =0.692, rDAS28=0.526, P<0.01). The synovial thickness in US were correlated with DAS28 Scores and biochemical examinations (ESR, CRP) (rDAS28=0.852, rESR=0.779, rCRP=0.587, P<0.01. The AUC and PI in CEUS were significantly correlated with US (rAUC=0.832, rPI=0.809, P<0.01=. The correlations among AUC, PI and ESR were better than that between US and ESR (rAUC=0.907, rPI=0.851, rUS=0.836, P<0.01=. The correlations among AUC, PI and CRP were better than that between US and CRP (rAUC=0.855, rPI=0.854, rUS=0.692, P<0.01. CONCLUSIONS: US was almost identical with DAS28 Scores and biochemical examinations (ESR, CRP) in diagnosis of RA activity, while CEUS was almost identical with DAS28 Scores and biochemical examinations (ESR, CRP). In diagnosis of RA, US may be better than DAS28 Scores, while CEUS better than US. Both of them were useful for evaluation of RA activity.

8.
Ultrasound Med Biol ; 40(9): 1998-2003, 2014 Sep.
Article in English | MEDLINE | ID: mdl-25023116

ABSTRACT

In order to explore the accuracy of ultrasonic whole stomach cylinder measurement (UWSCM) in the evaluation of gastric emptying, we measured the gastric emptying times (ET) at 25% (T1), 50% (T2) and 75% (T3) of healthy subjects and patients with diabetic gastropathy by UWSCM and scintigraphy. The ET of patients were compared with their clinical symptom scores. We found that the ET measured by UWSCM showed no significant difference with scintigraphy (p > 0.05). The correlation between them was good, and the correlation coefficient of T3 reached 0.744 (p < 0.05). All emptying times in the diabetic patients were longer than those in the healthy subjects (p < 0.05). The T3 in the diabetic group measured by UWSCM had the best correlation with the symptom index (r = 0.469, p < 0.05). We conclude that ET measured by UWSCM is accurate and T3 combining the symptoms index provides an accurate clinical basis for gastropathy.


Subject(s)
Diabetes Mellitus/physiopathology , Gastric Emptying/physiology , Stomach/diagnostic imaging , Adult , Female , Humans , Male , Middle Aged , Radionuclide Imaging , Reproducibility of Results , Time Factors , Ultrasonography
9.
Biomed Chromatogr ; 26(9): 1118-24, 2012 Sep.
Article in English | MEDLINE | ID: mdl-22213194

ABSTRACT

JCC76 is a novel nimesulide analog that selectively inhibits the human epidermal growth factor receptor 2 (HER2) overexpressing breast cancer cell proliferation and tumor progression. To support further pharmacological and toxicological studies of JCC76, a novel and rapid method using liquid chromatography and electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) has been developed and validated for the quantification of the compound in rat plasma. A C18 column was used for chromatographic separation, and the mobile phase was aqueous ammonium formate (pH 3.7; 5 mm)-methanol (1:9, v/v) with an isocratic elution. With a simple liquid-liquid extraction procedure using the mixture of methyl tert-butyl ether-hexane (1:2, v/v), the mean extraction efficiency of JCC76 in rat plasma was determined as 89.5-97.3% and no obvious matrix effect was observed. This method demonstrated a linear calibration range from 0.3 to 100 ng/mL for JCC76 in rat plasma and a small volume of sample consumption. The intra- and inter-assay accuracy and precision were within ±10%. The pharmacokinetics of JCC76 was also profiled using this validated method in rats. In conclusion, this rapid and sensitive method has been proven to effectively quantify JCC76 for pharmacokinetics study.


Subject(s)
Antineoplastic Agents/blood , Cyclohexanecarboxylic Acids/blood , Sulfonamides/blood , Animals , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacokinetics , Chromatography, High Pressure Liquid/methods , Cyclohexanecarboxylic Acids/chemistry , Cyclohexanecarboxylic Acids/pharmacokinetics , Drug Stability , Linear Models , Liquid-Liquid Extraction , Male , Rats , Rats, Sprague-Dawley , Reproducibility of Results , Sulfonamides/chemistry , Sulfonamides/pharmacokinetics , Tandem Mass Spectrometry/methods , Temperature
10.
Biomed Chromatogr ; 26(1): 101-8, 2012 Jan.
Article in English | MEDLINE | ID: mdl-21465504

ABSTRACT

In this work, a liquid chromatography coupled with electrospray ionization mass spectrometry (LC-ESI-MS) method was developed and validated for quantification of bile acids in fecal materials. Co-eluting matrix impurities in fecal materials have been shown to greatly suppress the ionization of analytes in mass spectrometry, which is known as the matrix effect. To correct large quantitative errors caused by the matrix effect, we developed a scheme that combined the standard addition method with internal standard (SA-IS). The fecal sample pretreatment involved a single step of extraction with ethanol. Bile acids were separated using a Luna C(18) column (150 mm, 2 mm i.d., 5 µm) with gradient elution. The deprotonated analytes were detected in selective ion monitoring mode. Our results showed that, by using this method, the accuracy of quantification was significantly improved in comparison to the conventional internal standard method. The linearity, sensitivity, accuracy and precision of the method were within the range of 0.05-5 µmol/L. This SA-IS method was successfully applied to the analysis of bile acids in the samples collected from patients diagnosed with inflammatory bowel disease.


Subject(s)
Bile Acids and Salts/analysis , Chromatography, Liquid/methods , Feces/chemistry , Spectrometry, Mass, Electrospray Ionization/methods , Bile Acids and Salts/chemistry , Bile Acids and Salts/isolation & purification , Colonic Pouches , Humans , Linear Models , Reproducibility of Results , Sensitivity and Specificity
11.
Eur J Med Chem ; 47(1): 432-444, 2012 Jan.
Article in English | MEDLINE | ID: mdl-22119125

ABSTRACT

Cyclooxygenase-2 (COX-2) inhibitor nimesulide inhibits the proliferation of various types of cancer cells mainly via COX-2 independent mechanisms, which makes it a good lead compound for anti-cancer drug development. In the presented study, a series of new nimesulide analogs were synthesized based on the structure-function analysis generated previously. Some of them displayed very potent anti-cancer activity with IC(50)s around 100 nM-200 nM to inhibit SKBR-3 breast cancer cell growth. CSUOH0901 (NSC751382) from the compound library also inhibits the growth of the 60 cancer cell lines used at National Cancer Institute Developmental therapeutics Program (NCIDTP) with IC(50)s around 100 nM-500 nM. Intraperitoneal injection with a dosage of 5  mg/kg/d of CSUOH0901 to nude mice suppresses HT29 colorectal xenograft growth. Pharmacokinetic studies demonstrate the good bioavailability of the compound.


Subject(s)
Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/pharmacology , Benzodioxoles/chemical synthesis , Benzodioxoles/pharmacology , Cyclooxygenase 2 Inhibitors/chemical synthesis , Cyclooxygenase 2 Inhibitors/pharmacology , Cyclooxygenase 2/metabolism , Sulfonamides/chemical synthesis , Sulfonamides/pharmacology , Animals , Antineoplastic Agents/pharmacokinetics , Antineoplastic Agents/toxicity , Benzodioxoles/pharmacokinetics , Benzodioxoles/toxicity , Cell Line, Tumor , Cell Proliferation/drug effects , Cyclooxygenase 2 Inhibitors/pharmacokinetics , Cyclooxygenase 2 Inhibitors/toxicity , Drug Design , G1 Phase Cell Cycle Checkpoints/drug effects , G2 Phase Cell Cycle Checkpoints/drug effects , Humans , Inhibitory Concentration 50 , Male , Mice , Rats , Sulfonamides/pharmacokinetics , Sulfonamides/toxicity , Xenograft Model Antitumor Assays
12.
PLoS One ; 6(10): e25689, 2011.
Article in English | MEDLINE | ID: mdl-21991333

ABSTRACT

Patterning of the animal embryo's antero-posterior (AP) axis is dependent on spatially and temporally regulated Hox gene expression. The murine Hoxd4 gene has been proposed to harbour two promoters, an upstream promoter P2, and a downstream promoter P1, that lie 5.2 and 1.1 kilobase pairs (kb) upstream of the coding region respectively. The evolutionarily conserved microRNA-10b (miR-10b) gene lies in the Hoxd4 genomic locus in the intron separating the non-coding exons 4 and 5 of the P2 transcript and directly adjacent to the proposed P1 promoter. Hoxd4 transcription is regulated by a 3' neural enhancer that harbours a retinoic acid response element (RARE). Here, we show that the expression profiles of Hoxd4 and miR-10b transcripts during neural differentiation of mouse embryonal carcinoma (EC) P19 cells are co-ordinately regulated, suggesting that both Hoxd4 and miR-10b expression is governed by the neural enhancer. Our observation that P1 transcripts are uncapped, together with the mapping of their 5' ends, strongly suggests that they are generated by Drosha cleavage of P2 transcripts rather than by transcriptional initiation. This is supported by the colocalization of P1 and P2 transcripts to the same posterior expression domain in the mouse embryo. These uncapped P1 transcripts do not appear to possess an Internal Ribosomal Entry Site (IRES), but accumulate within multiple punctate bodies within the nucleus suggesting that they play a functional role. Finally, similar uncapped Drosha-cleaved P1-like transcripts originating from the paralogous Hoxb4/miR-10a locus were also identified. We propose that these transcripts may belong to a novel class of regulatory RNAs.


Subject(s)
Cell Nucleus/metabolism , MicroRNAs/metabolism , RNA Caps/metabolism , Ribonuclease III/metabolism , Transcription Factors/metabolism , 5' Untranslated Regions/genetics , Animals , Base Sequence , Cell Differentiation/genetics , Embryo, Mammalian/cytology , Embryo, Mammalian/metabolism , Gene Expression Profiling , Gene Expression Regulation, Developmental , Humans , Mice , MicroRNAs/genetics , Molecular Sequence Data , Protein Biosynthesis/genetics , RNA Transport/genetics , RNA, Messenger/genetics , RNA, Messenger/metabolism , Ribosomes/metabolism , Transcription Factors/genetics
13.
J Steroid Biochem Mol Biol ; 126(1-2): 10-8, 2011 Aug.
Article in English | MEDLINE | ID: mdl-21458568

ABSTRACT

Third generation aromatase inhibitors (AIs) are more effective than tamoxifen in the treatment of estrogen receptor (ER) positive breast cancer. However, long-term use of AIs commonly results in resistance. We examined whether compound JCC76{Cyclohexanecarboxylic acid [3-(2,5-dimethyl-benzyloxy)-4-(methanesulfonyl-methyl-amino)-phenyl]-amide}, an analog of Cyclooxygenase-2 (COX-2) inhibitor nimesulide, can inhibit the growth of AI-insensitive breast cancer cells and the mechanisms by which the compound affects cell proliferation. LTEDaro (long term estrogen deprived MCF-7aro cell) cells, which are a model for AI resistance, were used in this study. JCC76 effectively inhibited LTEDaro cell proliferation with an IC(50) of 2.75 ± 0.31 µM. Further investigations reveal that the compound significantly induced apoptosis in LTEDaro cells by decreasing pAKT, BCL-2 and pBad protein levels, which were all up regulated in the cells after long term estrogen deprivation. LTEDaro tumor size and weight were decreased in ovariectomized nude mice treated with the compound, and cell apoptosis in the tumor tissue was increased compared to the control. The animal weight remained almost unchanged which indicated the low toxicity of the compound. These results suggest that JCC76 overcame AI resistance by inducing cell apoptosis as illustrated in the in vitro and in vivo models. Collectively, results from this study provide data to support that nimesulide analog JCC76 may be a new drug candidate to treat AI-resistant breast cancers. It could be also used as a lead to design and synthesize more potent derivatives.


Subject(s)
Breast Neoplasms/enzymology , Cell Proliferation/drug effects , Cyclohexanecarboxylic Acids/pharmacology , Cyclooxygenase 2 Inhibitors/pharmacology , Drug Resistance, Neoplasm , Sulfonamides/pharmacology , Animals , Apoptosis , Aromatase Inhibitors/pharmacology , Cell Line, Tumor , Cyclohexanecarboxylic Acids/chemistry , Cyclooxygenase 2 Inhibitors/chemistry , Female , Humans , Mice , Mice, Inbred BALB C , Proto-Oncogene Proteins c-akt/antagonists & inhibitors , Proto-Oncogene Proteins c-bcl-2/antagonists & inhibitors , Sulfonamides/chemistry
14.
J Steroid Biochem Mol Biol ; 122(4): 232-8, 2010 Oct.
Article in English | MEDLINE | ID: mdl-20542113

ABSTRACT

Cyclooxygenase-2 (COX-2) inhibitor nimesulide derivatives compounds A and B decreased aromatase activity in breast cancer cells via a novel mechanism different to aromatase inhibitors (AIs), and were defined as "aromatase suppressors". Breast carcinoma cells (MCF-7aro and T47Daro) transfected with aromatase full gene were used to explore the mechanisms of the two compounds. They dose and time-dependently suppressed aromatase activity in MCF-7aro and T47Daro cells in the nanomole range. However, they neither directly inhibited aromatase, nor improved aromatase degradation even at much higher concentrations. They could also suppress androgen stimulated cell growth, but did not affect estrogen enhanced cell proliferation. These results suggest that compounds A and B selectively interfere with aromatase in breast cancer cells, but not estrogen receptor (ER) downstream to disrupt androgen mediated cell growth. Interestingly, compound B effectively inhibited LTED (long-term estrogen deprived MCF-7aro cell) cell growth, which is a model for AIs resistance, with an IC(50) of 4.68 ± 0.54 µM. The results indicate that compound B could potentially overcome AI resistance in breast cancer cell and could be used as a lead to design more potent derivatives.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Aromatase Inhibitors/pharmacology , Breast Neoplasms/drug therapy , Carcinoma/drug therapy , Cyclooxygenase 2 Inhibitors/pharmacology , Sulfonamides/pharmacology , Anti-Inflammatory Agents, Non-Steroidal/chemistry , Aromatase Inhibitors/chemistry , Cell Line, Tumor , Cell Proliferation/drug effects , Cyclooxygenase 2 Inhibitors/chemistry , Estradiol/metabolism , Estrogens/metabolism , Female , Humans , Sulfonamides/chemistry , Testosterone/metabolism
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