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BACKGROUND: Insufficient attention has been given to examining the correlation between body composition and hyperuricemia, leading to inconsistent findings. The primary objective of this research is to explore the association between lean body mass index (LMI), visceral fat mass index (VFMI), and hyperuricemia. A specific emphasis will be placed on assessing the link between the ratio of lean body mass to visceral fat mass (LMI/VFMI) and hyperuricemia. METHODS: The present study employed a cross-sectional design and involved a total of 9,646 individuals who participated in the National Health and Nutrition Examination Survey (NHANES). To explore the associations among the variables, logistic and linear regressions were employed. Additionally, subgroup analyses and sensitivity analyses were conducted based on various characteristics. RESULTS: The results showed that LMI was positively associated with hyperuricemia (for Per-SD: OR = 1.88, 95%CI: 1.75, 2.01; for quartiles [Q4:Q1]: OR = 5.37, 95%CI: 4.31, 6.69). Meanwhile, VFMI showed a positive association with hyperuricemia (for Per-SD: OR = 2.02, 95%CI: 1.88, 2.16; for quartiles [Q4:Q1]: OR =8.37, 95%CI: 6.70, 10.47). When considering the effects of In LMI/VFMI, an L-shaped negative association with hyperuricemia was observed (for Per-SD: OR = 0.45, 95%CI: 0.42, 0.49; for quartiles [Q4:Q1]: OR = 0.16, 95%CI: 0.13, 0.20). Subgroup and sensitivity analyses demonstrated the robustness of this association across different subgroups. Additionally, the segmented regression analysis indicated a saturation effect of 5.64 for the In LMI/VFMI with hyperuricemia (OR = 0.20, 95%CI: 0.17, 0.24). For every 2.72-fold increase of In LMI/VFMI, the risk of hyperuricemia was reduced by 80%. CONCLUSION: The LMI/VFMI ratio is non-linearly associated with serum uric acid. Whether this association is causal needs to be confirmed in further longitudinal studies or Mendelian randomization.
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Hiperuricemia , Humanos , Estudos Transversais , Inquéritos Nutricionais , Gordura Intra-Abdominal , Ácido Úrico , Composição Corporal , Índice de Massa CorporalRESUMO
BACKGROUND: This study aimed to identify the biological functions, expression modes, and possible mechanisms underlying the relationship between metastatic human hepatocellular carcinoma (HCC) and MicroRNA-188-5p (miR-188) dysregulation using cell lines. METHODS: A decrease in miR-188 was detected in low and high metastatic HCC cells compared to that in normal hepatic cells and non-invasive cell lines. Gain- and loss-of-function experiments were performed in vitro to investigate the role of miR-188 in cancer cell (Hep3B, HepG2, HLF, and LM3) proliferation and migration. RESULTS: miR-188 mimic transfection inhibited the proliferation of metastatic HLF and LM3 cells but not non-invasive HepG2 and Hep3B cells; nonetheless, miR-188 suppression promoted the growth of HLF and LM3 cells. miR-188 upregulation inhibited the migratory rate and invasive capacity of HLF and LM3, rather than HepG2 and Hep3B cells, whereas transfection of a miR-188 inhibitor in HLF and LM3 cells had the opposite effects. Dual-luciferase reporter assays and bioinformatics prediction confirmed that miR-188 could directly target forkhead box N2 (FOXN2) in HLF and LM3 cells. Transfection of miR-188 mimics reduced FOXN2 levels, whereas miR-188 inhibition resulted in the opposite result, in HLF and LM3 cells. Overexpression of FOXN2 in HLF and LM3 cells abrogated miR-188 mimic-induced downregulation of proliferation, migration, and invasion. In addition, we found that miR-188 upregulation impaired tumor growth in vivo. CONCLUSIONS: In summary, this study showed thatmiR-188 inhibits the proliferation and migration of metastatic HCC cells by targeting FOXN2.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , MicroRNAs , Humanos , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , MicroRNAs/genética , MicroRNAs/metabolismo , Proliferação de Células/genética , Movimento Celular/genética , Regulação Neoplásica da Expressão Gênica , Linhagem Celular Tumoral , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/metabolismoRESUMO
Spinocerebellar ataxia type 1 (SCA1) is the third most common type of spinocerebellar ataxias in China. CAT interruptions in the pathogenic alleles of SCA1 patients had only been reported by limited documents and there was a lack of data based on the Chinese population. In this study, we detected CAT interrupted pathogenic alleles in SCA1 patients from 4 out of 79 (5.1%) Chinese families. Their total CAG repeats were larger (median 58 vs. 47, p < 0.001) but ages at onset were later (median 46 vs. 38, p = 0.020). The longest uninterrupted CAG repeats could explain 65.4% of the AAO variance, making an increase of 28.0% compared to the total CAG repeats. The interruption pattern was greatly different between Chinese cohort and Caucasian cohort, indicating the effect of race.
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An example of asymmetric Steglich-type rearrangement of enol lactones is reported. This highly enantioselective acyl transfer reaction is catalyzed by chiral isothiourea at ambient temperature and provides a useful synthetic approach to access enantioenriched spirotricyclic ß,ß'-diketones from a broad range of indanone or tetralone-derived lactones. Preliminary mechanistic studies suggest the initial formation of an N-acylated iminium cation intermediate that induces a following facial selective condensation.
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Cetonas , Lactonas , Estereoisomerismo , CatáliseRESUMO
In this work, we investigated the bioactivities of the essential oil (EO) extracted from the Rhododendron thymifolium and its principal germacrone against Lasioderma serricorne and Tribolium castaneum. The EO was obtained by steam distillation. Germacrone was obtained by cryogenic crystallization. The bioactivity of EO and germacrone was tested via contact and repellent activity assays. The results showed that EO and germacrone possessed contact and repellent activities against two species of insects. EO exhibited obvious contact activity against the L. serricorn adults, larvae and T. castaneum larvae with LD50 values of 29.15 µg/adult, 42.73 µg/larva, 19.65 µg/larva respectively. Germacrone exhibited excellent contact activity against the L. serricorne adults, larvae and the T. castaneum larvae with LD50 values of 17.18 µg/adult, 20.94 µg/larva, 20.93 µg/larva respectively. And at the highest testing concentrations (78.63 and 15.73 nL/cm2), the repellent activity of EO and germacrone on two target insects was comparable to that of the positive control (DEET) after 30 h exposure. In especially, in the treatment of the 120 h after the repellent activity of EO and germacrone against T.castaneum adults and larvae were still very significant and showed the same level percentage repellency as DEET. Meanwhile, germacrone exhibited inhibition of acetylcholinesterase activity with IC50 values of 3%. The results indicated that the EO of R. thymifolium and germacrone had the potential to be developed as natural insecticides and repellents for the control of T. castaneum and L. serricorne.
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Inibidores da Colinesterase/farmacologia , Besouros/efeitos dos fármacos , Inseticidas/farmacologia , Óleos Voláteis/farmacologia , Rhododendron/química , Animais , Inibidores da Colinesterase/química , Proteínas de Insetos/antagonistas & inibidores , Proteínas de Insetos/metabolismo , Repelentes de Insetos/química , Repelentes de Insetos/farmacologia , Inseticidas/química , Dose Letal Mediana , Óleos Voláteis/química , Sesquiterpenos de Germacrano/farmacologia , Tribolium/química , Tribolium/efeitos dos fármacosRESUMO
Chromohalobacter salexigens DSM 3043 can grow on N,N-dimethylglycine (DMG) as the sole C, N, and energy source and utilize sarcosine as the sole N source under aerobic conditions. However, little is known about the genes and enzymes involved in the conversion of DMG to sarcosine in this strain. In the present study, gene disruption and complementation assays indicated that the csal_0990, csal_0991, csal_0992, and csal_0993 genes are responsible for DMG degradation to sarcosine. The csal_0990 gene heterologously expressed in Escherichia coli was proven to encode an unusual DMG dehydrogenase (DMGDH). The enzyme, existing as a monomer of 79 kDa with a noncovalently bound flavin adenine dinucleotide, utilized both DMG and sarcosine as substrates and exhibited dual coenzyme specificity, preferring NAD+ to NADP+ The optimum pH and temperature of enzyme activity were determined to be 7.0 and 60°C, respectively. Kinetic parameters of the enzyme toward its substrates were determined accordingly. Under high-salinity conditions, the presence of DMG inhibited growth of the wild type and induced the production and accumulation of trehalose and glucosylglycerate intracellularly. Moreover, exogenous addition of DMG significantly improved the growth rates of the four DMG- mutants (Δcsal_0990, Δcsal_0991, Δcsal_0992, and Δcsal_0993) incubated at 37°C in S-M63 synthetic medium with sarcosine as the sole N source. 13C nuclear magnetic resonance (13C-NMR) experiments revealed that not only ectoine, glutamate, and N-acetyl-2,4-diaminobutyrate but also glycine betaine (GB), DMG, sarcosine, trehalose, and glucosylglycerate are accumulated intracellularly in the four mutants.IMPORTANCE Although N,N-dimethylglycine (DMG) dehydrogenase (DMGDH) activity was detected in cell extracts of microorganisms, the genes encoding microbial DMGDHs have not been determined until now. In addition, to our knowledge, the physiological role of DMG in moderate halophiles has never been investigated. In this study, we identified the genes involved in DMG degradation to sarcosine, characterized an unusual DMGDH, and investigated the role of DMG in Chromohalobacter salexigens DSM 3043 and its mutants. Our results suggested that the conversion of DMG to sarcosine is accompanied by intramolecular delivery of electrons in DMGDH and intermolecular electron transfer between DMGDH and other electron acceptors. Moreover, an unidentified methyltransferase catalyzing the production of glycine betaine (GB) from DMG but sharing no homology with the reported sarcosine DMG methyltransferases was predicted to be present in the cells. The results of this study expand our understanding of the physiological role of DMG and its catabolism to sarcosine in C. salexigens.
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Chromohalobacter/genética , Genes Bacterianos , Sarcosina/análogos & derivados , Sarcosina/metabolismo , Chromohalobacter/metabolismo , Teste de Complementação GenéticaRESUMO
Spinocerebellar ataxia type 3 (SCA3) is caused by unstable expanded CAG repeats (expCAGs) in ATXN3. Factors associated with intergenerational instability (delta-expCAG) and genetic anticipation in SCA3 have never been reported in Chinese mainland. Here, we demonstrated that unstable transmissions occurred more often in sons than in daughters (91% vs 72%, Fisher's exact test, p = 0.012). The extended delta-expCAG of father-son transmissions was greater than that of mother-son transmissions (3.8 ± 2.3 repeats vs 1.6 ± 1.0 repeats, Mann-Whitney U, p = 0.001). Genetic anticipation was frequently observed between generations but not affected by the delta-expCAG.
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Antecipação Genética/genética , Povo Asiático/genética , Ataxina-3/genética , Doença de Machado-Joseph/epidemiologia , Doença de Machado-Joseph/genética , Proteínas Repressoras/genética , Expansão das Repetições de Trinucleotídeos/genética , Adulto , China/epidemiologia , Feminino , Predisposição Genética para Doença/epidemiologia , Predisposição Genética para Doença/genética , Humanos , Doença de Machado-Joseph/diagnóstico , Masculino , Pessoa de Meia-Idade , Repetições de Trinucleotídeos/genética , Adulto JovemRESUMO
Penisarins A (1) and B (2), sesquiterpene coumarins with an unusual tricyclic sesquiterpene system, were isolated from endophytic Penicillium sp. KMU18029. Their structures were elucidated on the basis of spectroscopic methods, single-crystal X-ray diffraction, and electronic circular dichroism calculations. Compound 2 showed significant cytotoxicities against two human cancer cell lines, HL-60 and SMMC-7721, with IC50 values of 3.6 ± 0.2 and 3.7 ± 0.2 µM, respectively.
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Cumarínicos/isolamento & purificação , Penicillium/química , Sesquiterpenos/isolamento & purificação , Linhagem Celular Tumoral , Dicroísmo Circular , Cumarínicos/química , Cristalografia por Raios X , Humanos , Estrutura Molecular , Sesquiterpenos/químicaRESUMO
Although some bacteria, including Chromohalobacter salexigens DSM 3043, can use glycine betaine (GB) as a sole source of carbon and energy, little information is available about the genes and their encoded proteins involved in the initial step of the GB degradation pathway. In the present study, the results of conserved domain analysis, construction of in-frame deletion mutants, and an in vivo functional complementation assay suggested that the open reading frames Csal_1004 and Csal_1005, designated bmoA and bmoB, respectively, may act as the terminal oxygenase and the ferredoxin reductase genes in a novel Rieske-type oxygenase system to convert GB to dimethylglycine in C. salexigens DSM 3043. To further verify their function, BmoA and BmoB were heterologously overexpressed in Escherichia coli, and 13C nuclear magnetic resonance analysis revealed that dimethylglycine was accumulated in E. coli BL21(DE3) expressing BmoAB or BmoA. In addition, His-tagged BmoA and BmoB were individually purified to electrophoretic homogeneity and estimated to be a homotrimer and a monomer, respectively. In vitro biochemical analysis indicated that BmoB is an NADH-dependent flavin reductase with one noncovalently bound flavin adenine dinucleotide (FAD) as its prosthetic group. In the presence of BmoB, NADH, and flavin, BmoA could aerobically degrade GB to dimethylglycine with the concomitant production of formaldehyde. BmoA exhibited strict substrate specificity for GB, and its demethylation activity was stimulated by Fe2+ Phylogenetic analysis showed that BmoA belongs to group V of the Rieske nonheme iron oxygenase (RO) family, and all the members in this group were able to use quaternary ammonium compounds as substrates.IMPORTANCE GB is widely distributed in nature. In addition to being accumulated intracellularly as a compatible solute to deal with osmotic stress, it can be utilized by many bacteria as a source of carbon and energy. However, very limited knowledge is presently available about the molecular and biochemical mechanisms for the initial step of the aerobic GB degradation pathway in bacteria. Here, we report the molecular and biochemical characterization of a novel two-component Rieske-type monooxygenase system, GB monooxygenase (BMO), which is responsible for oxidative demethylation of GB to dimethylglycine in C. salexigens DSM 3043. The results gained in this study extend our knowledge on the catalytic reaction of microbial GB degradation to dimethylglycine.
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Betaína/metabolismo , Chromohalobacter/enzimologia , Chromohalobacter/metabolismo , Desmetilação , Oxigenases de Função Mista/metabolismo , Oxigenases/metabolismo , Proteínas de Bactérias/genética , Catálise , Chromohalobacter/genética , Chromohalobacter/crescimento & desenvolvimento , Dinitrocresóis/farmacologia , Ácido Edético/farmacologia , Escherichia coli/genética , Escherichia coli/metabolismo , Deleção de Genes , Cinética , Metais/farmacologia , Oxigenases de Função Mista/efeitos dos fármacos , Oxigenases de Função Mista/genética , Peso Molecular , Mutação , Fases de Leitura Aberta , Oxirredução , Oxirredutases/genética , Oxigenases/efeitos dos fármacos , Oxigenases/genética , Sarcosina/análogos & derivados , Alinhamento de Sequência , Análise de Sequência de Proteína , Especificidade por SubstratoRESUMO
Chromohalobacter salexigens DSM 3043 can grow over a wide range of salinity, which makes it as an excellent model organism for understanding the mechanism of prokaryotic osmoregulation. Functional analysis of C. salexigens genes is an essential way to reveal their roles in cellular osmoregulation. However, the lack of an effective markerless gene deletion system has prevented construction of multiple gene deletion mutants for the members in the genus. Here, we report the development of a markerless gene deletion system in C. salexigens using allelic exchange method. In this system, the in vitro mutant allele of target gene was inserted into a pK18mobsacB-based integrative vector pMDC21, which contained a chloramphenicol resistance cassette as the positive selection marker and a sacB gene from Bacillus subtilis as the counterselectable marker. To validate this system, two single-gene deletion mutants and a double-gene deletion mutant were constructed. In addition, our results showed that growth of the merodiploids and sucrose screening at 25 °C were more effective to decrease the occurrence of spontaneous sucrose resistance colonies than at higher temperature (30 or 37 °C), and growth of the merodiploids in mineral salt medium instead of the complex medium was critical to increase the recovery rate of deletion mutants.
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Chromohalobacter/genética , Deleção de Genes , Genética Reversa/métodos , Genes Bacterianos , Recombinação HomólogaRESUMO
Objective To explore the efficacy and toxicities of gemcitabine combined with S-1 in treating locally advanced and metastatic pancreatic ductal adenocarcinoma and prognostic factors. Methods We retrospectively analyzed the clinical data of patients with locally advanced and metastatic pancreatic cancer receiving gemcitabine and S-1 as first-line therapy in the Department of Medical Oncology,Peking Union Medical College Hospital from January 2014 to January 2017.Gemcitabine was administered at a dose of 1000 mg/m2 over 30 min-utes on days 1 and 8,and oral S-1 at a dose of 40-60 mg twice daily from days 1 to 14,repeated every 3 weeks.All patients received at least two cycles of chemotherapy. Results A total of 60 patients were included,13(22%) achieved partial remission,37(61%) had stable disease,and 10(17%) experienced progressive disease.The median progression-free survival was 7 months(95% CI=6-10 months) and the median overall survival was 12 months(95% CI=9-20 months).Both univariate and multivariate analyses of prognostic factors showed primary resection was significant in predicting shorter progression-free survival and lung metastasis was significant for shorter overall survival.The most common grade 3-4 toxicities were neutropenia(27%) and leukopenia(18%). Conclusion Gemcitabine combined with S-1 is an effective regimen with manageable toxicities in the treatment of advanced pancreatic cancer and can be used as first-line therapy.
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Adenocarcinoma/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica , Desoxicitidina/análogos & derivados , Ácido Oxônico/uso terapêutico , Neoplasias Pancreáticas/tratamento farmacológico , Tegafur/uso terapêutico , Desoxicitidina/administração & dosagem , Desoxicitidina/uso terapêutico , Intervalo Livre de Doença , Combinação de Medicamentos , Humanos , Ácido Oxônico/administração & dosagem , Estudos Retrospectivos , Tegafur/administração & dosagem , Resultado do Tratamento , GencitabinaRESUMO
Objective To study the single nucleotide polymorphisms (SNPs)that predict a patient's risk of grade 2-3 paclitaxel-induced peripheral sensory neuropathy (PSN) in Chinese Han populations.Methods Totally 216 patients received paclitaxel in Peking Union Medical College Hospital from May 2014 to December 2016 were enrolled.DNA was isolated from peripheral blood.Genotyping for eight candidate SNPs was performed on Sequenom-MassARRARYiPLEX platform.Patients were followed up and PSN was assessed by trained physicians according to National Cancer Institute-Common Terminology Criteria for Adverse Events v4.03.Results A total of 209 patients entered the final analysis.Among the candidate SNPs,only rs4141404:A>C(LIMK2) was significantly associated with grade 2/3 PSN (OR:4.32,95%CI:2.37-7.89,P<0.0001).In multivariate logistic regression analysis,both rs4141404:A>C(LIMK2) and history of receiving platinum compound (OR:2.70,95%CI:1.32-5.51,P=0.007) were associated with grade 2/3 PSN.Conclusion rs4141404:A>C(LIMK2) may be the markers of risk of grade 2/3 PSN.
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Quinases Lim/genética , Paclitaxel/efeitos adversos , Doenças do Sistema Nervoso Periférico/induzido quimicamente , Polimorfismo de Nucleotídeo Único , Povo Asiático , China , Genótipo , Humanos , Doenças do Sistema Nervoso Periférico/genéticaRESUMO
BACKGROUND: Currently, the use of mushrooms as functional foods, nutraceuticals or phytopharmaceuticals source has risen. In contrast, the possible cellular cytotoxicity and immunostimulatory activity of Pleurotus eryngii (DC. ex Fr.) Quel protein (PEQP) is unknown. Here we report extraction, anti-tumorigenic and immunostimulatory activity of PEQP in vitro. RESULTS: PEQP was extracted from the dried fruiting bodies of P. eryngii, purified and characterised. Its in vitro antiproliferative activity was then evaluated in human non-small cell lung cancer A549 (NSCLC), stomach adenocarcinoma BGC-823, hepatocellular carcinoma HepG2 and gastric carcinoma HGC-27 cell lines using conventional cancer drugs (paclitaxel, doxorubicin and mitomycin C) as positive controls. The protein fractions (PEQP 1, 2, 3 and 4) obtained inhibited tumour cell proliferation dose-dependently with fraction PEQP 2 having significant (P < 0.05) toxicity in all tumour cells. PEQP had no significant toxicity on normal liver Chang cells but their proliferation was significantly inhibited by mitomycin C. Moreover, PEQP stimulated the proliferation, lysosomal enzyme activity, pinocytosis, nitric oxide and hydrogen peroxide production of RAW 264.7 cell lines dose-dependently. CONCLUSION: Based on these results, P. eryngii protein has a potential application in functional foods as a natural anti-tumour agent with immunostimulatory activity.
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Adjuvantes Imunológicos/farmacologia , Antinematódeos/farmacologia , Proteínas Fúngicas/farmacologia , Pleurotus/química , Carcinoma Pulmonar de Células não Pequenas , Linhagem Celular , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Carpóforos/química , Proteínas Fúngicas/isolamento & purificação , Células Hep G2 , Humanos , Neoplasias Hepáticas , Neoplasias Pulmonares , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Neoplasias GástricasRESUMO
The chemical epigenetic modifier 5-azacitidine (5-Aza C), a DNA methyltransferase inhibitor, was used to manipulate the endophytic fungus Penicillium sp. KMU18029. From its rice fermentation extract, a new polyketone compound (3S,4R)-3,4,8-trihydroxy-6-methyl-3,4-dihydronaphthalen-1(2H)-one (1), along with 13 known compounds, 3,4,8-trihydroxy-6-(hydroxymethyl)-3,4-dihydronaphthalen-1(2H)-one (2), decaturin B (3), 15-hydroxydecaturin A (4), oxalicine A (5), pileotin A (6), pyrandecarurin A (7), decaturenol A (8), decaturenoid (9), penisarins A (10), oxaline (11), (4E,8E)-N-D-2'-hydroxyocta-decanoyl-1-O-ß-D-glycopy-ranosyl-9-methyl-4,8-sphingadienine (12), ergosterol (13) and stigma-5-en-3-O-ß-glucoside (14), were separated. Among the known compounds, 2, 7, 12 and 14 were not found in our previous research on this strain. The structure of the new compound was identified by spectroscopic techniques such as HR-ESIMS, 1D NMR, 2D NMR and CD. Furthermore, all the isolated compounds were tested for their antimicrobial activities, and only compounds 1, 2 and 11 showed weak activities against S. aureus, with MICs of 128 µg/mL.
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Azacitidina , Penicillium , Penicillium/química , Estrutura Molecular , Staphylococcus aureus , Espectroscopia de Ressonância Magnética , Epigênese GenéticaRESUMO
A new phthalide derivative named paramlyktone (1) and a new arborinane-type triterpenoid named paramyrpenoid (2), together with ten previously described trichothecenes derivatives (3-12) were isolated and identified from a rhizospheric soil-derived Paramyrothecium sp. KMU22107 associated with Delphinium yunnanense. Their structural elucidation was achieved by the comprehensive analysis of spectroscopic data and comparison with literature values. Notably, paramyrpenoid (2) was the first example of an arborinane-type triterpenoid with a double bond at Δ12(13) and an additional methyl motif at C-8. This was the first report of arborinane-type triterpenoids from a fungus belonging to Paramyrothecium genus. In pharmacological studies, paramyrpenoid (2) demonstrated significant cytotoxic activity against the HL-60, SW480, A-549, MDA-MB-231 and SMMC-7721 cell lines, with IC50 values from 2.0 to 16.1 µM. Compounds 1 and 2 were also evaluated for anti-inflammatory, anti-acetylcholinesterase (AChE), and protein tyrosine phosphatase 1B (PTP1B) inhibitory activities in vitro.
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Low-dimensional ferroelectric tunnel junctions are appealing for the realization of nanoscale nonvolatile memory devices due to their inherent advantages of device miniaturization. Those based on current mechanisms have limitations, including low tunneling electroresistance (TER) effects and complex heterostructures. Here, we introduce an entirely new TER mechanism to construct a nanotube ferroelectric tunnel junction with ferroelectric nanotubes as the tunneling region. When rolling a ferroelectric monolayer into a nanotube, due to the coexistence of its intrinsic ferroelectric polarization with the flexoelectric polarization induced by bending, a metal-insulator transition occurs depending on the radiative polarization states. For the pristine monolayer, its out-of-plane polarization is tunable by an in-plane electric field, and the conducting states of the ferroelectric nanotube can thus be tuned between metallic and insulating states via axial electric means. Using α-In2Se3 as an example, our first-principles density functional theory calculations and nonequilibrium Green's function formalism confirm the feasibility of the TER mechanism and indicate an ultrahigh TER ratio that exceeds 9.9 × 1010% of the proposed nanotube ferroelectric tunnel junctions. Our findings provide a promising approach based on simple homogeneous structures for high density ferroelectric microelectric devices with excellent ON/OFF performance.
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Two novel fungal polyketides, phometides A (1) and B (2), together with four known compounds (3-6), were isolated from the endophytic fungus Phoma sp. YUD17001 obtained from Gastrodia elata Blume. The structures were elucidated based on spectroscopic analyses, X-ray crystal diffraction, and time-dependent density functional theory/electronic circular dichroism (TDDFT/ECD) calculations. Structurally, phometide A (1) represented the first example of C12 polyketide characterized by an unusual tetrahydrobenzofuran-3(2H)-one core with an α,ß-unsaturated ketone functionality, while phometide B (2) was an unprecedented molecule containing a 2-pentylcycloheptan-1-one scaffold. In an antimicrobial activity assay, phometide A (1) exhibited significant inhibitory activity against Staphylococcus aureus with MIC value of 4 µg/mL. Phometide B (2) showed moderate antifungal activity against Candida albicans with an MIC value of 16 µg/mL. Furthermore, compounds 1 and 2 were evaluated for their acetylcholinesterase inhibitory and cytotoxic activities.
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Gastrodia , Policetídeos , Estrutura Molecular , Phoma , Acetilcolinesterase , Dicroísmo CircularRESUMO
Hematopoietic stem and progenitor cells (HSPCs) that have impaired differentiation can transform into leukemic blasts. However, the mechanism that controls differentiation remains elusive. Here, we show that the genetic elimination of Proteinase 3 (PRTN3) in mice led to spontaneous myeloid differentiation. Mechanistically, our findings indicate that PRTN3 interacts with the N-terminal of STAT3, serving as a negative regulator of STAT3-dependent myeloid differentiation. Specifically, PRTN3 promotes STAT3 ubiquitination and degradation, while simultaneously reducing STAT3 phosphorylation and nuclear translocation during G-CSF-stimulated myeloid differentiation. Strikingly, pharmacological inhibition of STAT3 (Stattic) partially counteracted the effects of PRTN3 deficiency on myeloid differentiation. Moreover, the deficiency of PRTN3 in primary AML blasts promotes the differentiation of those cells into functional neutrophils capable of chemotaxis and phagocytosis, ultimately resulting in improved overall survival rates for recipients. These findings indicate PRTN3 exerts an inhibitory effect on STAT3-dependent myeloid differentiation and could be a promising therapeutic target for the treatment of acute myeloid leukemia.
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Diferenciação Celular , Leucemia Mieloide Aguda , Mieloblastina , Fator de Transcrição STAT3 , Animais , Humanos , Camundongos , Leucemia Mieloide Aguda/patologia , Leucemia Mieloide Aguda/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mieloblastina/metabolismo , Mieloblastina/genética , Células Mieloides/metabolismo , Células Mieloides/patologia , Fosforilação , Fator de Transcrição STAT3/metabolismo , UbiquitinaçãoRESUMO
RATIONALE: Giant intracranial aneurysms pose a significant threat due to high mortality rates upon rupture, prompting interventions such as neurosurgical clipping or endovascular coiling. PATIENT CONCERNS: We present a rare case involving a 47-year-old female with a history of successfully treated ruptured giant intracranial aneurysms. Six months post-surgical clipping, she developed symptoms of acute ischemic stroke, prompting the decision for neurosurgical coiling and stent-assisted aneurysm coil embolization due to recurrent intracranial aneurysms. DIAGNOSES: Subsequently, occlusion occurred at the previously implanted stent site during embolization, necessitating exploration of alternative therapeutic options. Digital subtraction angiography confirmed stent occlusion in the right middle cerebral artery. INTERVENTIONS: Despite an initial unsuccessful attempt using a direct aspiration first-pass technique, the patient underwent successful mechanical thrombectomy with a retrievable stent, leading to successful reperfusion. This study aims to highlight the challenges and therapeutic strategies in managing delayed cerebral vascular occlusion following stent-assisted coil embolization, emphasizing the significance of exploring alternative interventions to enhance patient outcomes. OUTCOMES: The patient achieved successful reperfusion, and the study underscores the importance of recognizing and addressing delayed cerebral vascular occlusion after stent-assisted coil embolization for recurrent cerebral aneurysms. LESSONS: Our findings suggest that retrievable stent mechanical thrombectomy may serve as a viable therapeutic option in challenging scenarios, emphasizing the need for further exploration of alternative interventions to enhance patient care.
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Aneurisma Roto , Embolização Terapêutica , Aneurisma Intracraniano , AVC Isquêmico , Tromboembolia , Feminino , Humanos , Pessoa de Meia-Idade , Aneurisma Roto/cirurgia , Angiografia Cerebral , Embolização Terapêutica/métodos , Aneurisma Intracraniano/complicações , Aneurisma Intracraniano/cirurgia , AVC Isquêmico/complicações , Estudos Retrospectivos , Stents , Trombectomia , Tromboembolia/complicações , Resultado do TratamentoRESUMO
Considering the instability and toxicity of 3D Pb-based perovskite nanocrystals, lead-free low-dimensional organic-inorganic hybrid metal halides have attracted widespread attention as potential substitutes. Herein, two new tin-based 0D halides [H4BAPP]SnBr5·Br and [H4BAPP]SnCl5·Cl·H2O (BAPP = 1,4-bis(3-aminopropyl)piperazine) were synthesized successfully based on [SnX5]3- as an emission center. Typically, [H4BAPP]SnBr5·Br and [H4BAPP]SnCl5·Cl·H2O display broadband yellow and yellow-green light emissions originating from the radiative recombination of self-trapped excitons (STEs). The photoluminescence quantum yields (PLQYs) of the two compounds were calculated to be 19.27% and 2.36%, respectively. Furthermore, the excellent chemical and thermal stability and broadband light emissions reveal their potential application in solid-state white lighting diodes.