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1.
Sci Bull (Beijing) ; 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38594099

RESUMO

Magnetic impurities in superconductors are of increasing interest due to emergent Yu-Shiba-Rusinov (YSR) states and Majorana zero modes for fault-tolerant quantum computation. However, a direct relationship between the YSR multiple states and magnetic anisotropy splitting of quantum impurity spins remains poorly characterized. By using scanning tunneling microscopy, we systematically resolve individual transition-metal (Fe, Cr, and Ni) impurities induced YSR multiplets as well as their Zeeman effects in the K3C60 superconductor. The YSR multiplets show identical d orbital-like wave functions that are symmetry-mismatched to the threefold K3C60(1 1 1) host surface, breaking point-group symmetries of the spatial distribution of YSR bound states in real space. Remarkably, we identify an unprecedented fermion-parity-preserving quantum phase transition between ground states with opposite signs of the uniaxial magnetic anisotropy that can be manipulated by an external magnetic field. These findings can be readily understood in terms of anisotropy splitting of quantum impurity spins, and thus elucidate the intricate interplay between the magnetic anisotropy and YSR multiplets.

2.
Nano Lett ; 23(21): 10081-10088, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37903418

RESUMO

Nontrivial electronic states are attracting intense attention in low-dimensional physics. Though chirality has been identified in charge states with a scalar order parameter, its intertwining with charge density waves (CDW), film thickness, and the impact on the electronic behaviors remain less well understood. Here, using scanning tunneling microscopy, we report a 2 × 2 chiral CDW as well as a strong suppression of the Te-5p hole-band backscattering in monolayer 1T-TiTe2. These exotic characters vanish in bilayer TiTe2 in a non-CDW state. Theoretical calculations prove that chirality comes from a helical stacking of the triple-q CDW components and, therefore, can persist at the two-dimensional limit. Furthermore, the chirality renders the Te-5p bands with an unconventional orbital texture that prohibits electron backscattering. Our study establishes TiTe2 as a promising playground for manipulating the chiral ground states at the monolayer limit and provides a novel path to engineer electronic properties from an orbital degree.

3.
Nat Commun ; 14(1): 2622, 2023 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-37147296

RESUMO

Charge modulations have been widely observed in cuprates, suggesting their centrality for understanding the high-Tc superconductivity in these materials. However, the dimensionality of these modulations remains controversial, including whether their wavevector is unidirectional or bidirectional, and also whether they extend seamlessly from the surface of the material into the bulk. Material disorder presents severe challenges to understanding the charge modulations through bulk scattering techniques. We use a local technique, scanning tunneling microscopy, to image the static charge modulations on Bi2-zPbzSr2-yLayCuO6+x. The ratio of the phase correlation length ξCDW to the orientation correlation length ξorient points to unidirectional charge modulations. By computing new critical exponents at free surfaces including that of the pair connectivity correlation function, we show that these locally 1D charge modulations are actually a bulk effect resulting from classical 3D criticality of the random field Ising model throughout the entire superconducting doping range.

4.
Sci Rep ; 13(1): 6019, 2023 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-37055430

RESUMO

In order to improve the measuring accuracy of the Hemispherical Resonator Gyro under variable temperature, aiming at the problem of "external temperature is unavailable and internal temperature is unmeasurable," a multiple regression based method is proposed for compensating temperature error in the gyro. The relationship between the internal temperature and the resonant frequency of the gyro is analyzed theoretically. According to a constant temperature experiment, a linear relationship between them is derived based on the least square method. The analysis of a temperature-rising experiment shows that the correlation of the gyro output with the internal temperature is much higher than that with the external temperature. Therefore, taking the resonant frequency as an independent variable, a multiple regression model is established for compensating the temperature error. The compensation effect of the model is verified by temperature-rising and temperature-dropping experiments, which show that the output sequence before compensation is not stable, while it is stable after compensation. After compensation, the drift of the gyro decreases by 62.76% and 48.48%, respectively, and its measuring accuracy becomes equivalent to that at the constant temperature. The experimental results verify the feasibility and effectiveness of the model developed for indirect compensation of temperature error.

5.
Clin Endocrinol (Oxf) ; 98(5): 682-691, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36746677

RESUMO

OBJECTIVES: To quantify the effect of carnitine on glucose and lipid metabolic profiles and fertility outcomes in women with Polycystic ovary syndrome (PCOS). DESIGN: A systematic review and meta-analysis were conducted. PATIENTS: Women with PCOS diagnosed by Rotterdam or Androgen Excess Society (AES) criteria and taking carnitine supplement were assessment. MEASUREMENTS: Fertility outcomes (ovulation, clinical pregnancy, live birth, and miscarriage), lipid parameters (BMI, triglyceride, total cholesterol, high-density lipoprotein, low-density lipoprotein), fasting glucose and insulin, and Homeostatic Model Assessment for Insulin Resistance (HOMA-IR). RESULTS: In total, 839 participants were included in this analysis. The dosage of carnitine and treatment duration reported by studies varied from 250 mg to 3000 mg daily and 84 to 90 days, respectively. The publication bias was absent. Compared with placebo, carnitine significantly improved ovulation rates (RR 3.42, 95% CI 2.39 to 4.89, I2 = 0%) and pregnancy rates (RR 11.05, 95% CI 1.21 to 100.58, I2 = 79%). None of included studies reported live birth. After treatment, carnitine resulted in significant reductions relative to baseline in body mass index (BMI, MD -0.93 kg/m2, 95% CI -1.15 to -0.70, I2 = 55.0%), insulin levels (MD -2.47 mIU/L, 95% CI -4.49 to -0.45, I2 = 0%) and the Homeostasis Model Assessment index (MD -0.67, 95% CI -1.20 to -0.14, I2 = 0%) than placebo, but not for lipid profiles including triglyceride, total cholesterol, and low-density lipoprotein. CONCLUSION: With the available literature, carnitine seems to improve ovulation and clinical pregnancy and insulin resistance, BMI in women with PCOS. These effects are warranted to be further validated, due to insufficient statistical power.


Assuntos
Resistência à Insulina , Síndrome do Ovário Policístico , Gravidez , Feminino , Humanos , Síndrome do Ovário Policístico/tratamento farmacológico , Glucose , Carnitina , Fertilidade , Insulina , Lipoproteínas LDL , Triglicerídeos , Colesterol , Lipídeos
6.
China Pharmacy ; (12): 144-149, 2023.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-959738

RESUMO

OBJECTIVE To study the toxic mechanism of Mahuang xixin fuzi decoction (MXF) on normal mice. METHODS Totally 48 SPF grade BABL/C mice were randomly divided into blank group, MXF low-dose, medium-dose and high-dose groups, with 12 mice in each group. MXF low-dose, medium-dose and high-dose groups were given drug intragastrically at the dose of 11.262, 33.786, 45.050 g/kg, respectively. Blank group was administered with equal volume of normal saline, once a day, for consecutive 7 d. The body weight, anal temperature and survival rate were recorded, organ index and serum biochemical factors were detected. After the last administration, fecal samples of mice were collected and detected by UHPLC-QE/MS. RESULTS Compared with blank group, the body weight was decreased significantly from the 3rd to the 5th day after administration in MXF medium-dose group, and from the 2nd to the 7th day after administration in MXF high-dose group significantly (P<0.05). There was no significant difference in anal temperature among the treatment groups; the average survival rates of MXF medium-dose and high-dose groups were 58.33% and 50.00%, respectively. Compared with blank group, there were significant difference in the indexes of spleen, lung, thymus, adrenal gland and creatine kinase in MXF low-dose, medium-dose and high-dose groups, the testis index in MXF low-dose and high-dose groups, the creatine kinase isoenzyme/creatine kinase ratio in MXF low-dose group, the α-hydroxybutyrate dehydrogenase, lactate dehydrogenase and alkaline phosphatase in MXF medium-dose group, the urine and cystatin C in MXF medium-dose and high-dose groups (P<0.05). The fecal metabonomic analysis showed that 19 biomarkers such as phenylpyruvate, L-tyrosine, phosphatidylcholine, glycerol 3-phosphate in MXF low-dose, medium-dose and high-dose groups were significantly different from those in the blank group. CONCLUSIONS When MXF reaches a certain dose, it will have adverse effects on the body weight, multiple organs and serum biochemical indicators of mice, thus showing a certain toxic effect. Its mechanism may be related to disrupting the intestinal flora metabolism, causing inflammatory reaction and immune disorders.

7.
International Eye Science ; (12): 607-611, 2023.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-965786

RESUMO

Cataract surgery has moved from the era of anti-blindness surgery to the era of refractive surgery, and vision-related quality of life has become an important prognostic indicator for cataract surgery. Since indicators like visual acuity are difficult to describe the visual quality of patients in a panoramic view, the evaluation of visual function based on subjective experience has received attention in clinical and scientific research. The visual functioning index(VF-14)is the first scale applied to assess the visual function in cataract surgery, and is widely used internationally so far. This review presented the research history of VF-14, scrutinized its clinical applicability, and summarized the research and application of VF-14 in the assessment of visual function, evaluation of surgical efficacy, and postoperative follow-up from three groups of people with cataract, refractive discomforts, and other common ophthalmic diseases, aiming to provide a reference for the clinical application of the VF-14.

8.
Natl Sci Rev ; 9(4): nwab225, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35530436

RESUMO

The microscopic understanding of high-temperature superconductivity in cuprates has been hindered by the apparent complexity of crystal structures in these materials. We used scanning tunneling microscopy and spectroscopy to study the electron-doped copper oxide compound Sr1- x Nd x CuO2, which has only bare cations separating the CuO2 planes and thus the simplest infinite-layer structure of all cuprate superconductors. Tunneling conductance spectra of the major CuO2 planes in the superconducting state revealed direct evidence for a nodeless pairing gap, regardless of variation of its magnitude with the local doping of trivalent neodymium. Furthermore, three distinct bosonic modes are observed as multiple peak-dip-hump features outside the superconducting gaps and their respective energies depend little on the spatially varying gaps. As well as the bosonic modes, with energies identical to those of the external, bending and stretching phonons of copper oxides, our findings reveal the origin of the bosonic modes in lattice vibrations rather than spin excitations.

9.
Preprint em Inglês | bioRxiv | ID: ppbiorxiv-489997

RESUMO

SARS-CoV-2 Omicron sublineages BA.2.12.1, BA.4 and BA.5 exhibit higher transmissibility over BA.21. The new variants receptor binding and immune evasion capability require immediate investigation. Here, coupled with Spike structural comparisons, we show that BA.2.12.1 and BA.4/BA.5 exhibit comparable ACE2-binding affinities to BA.2. Importantly, BA.2.12.1 and BA.4/BA.5 display stronger neutralization evasion than BA.2 against the plasma from 3-dose vaccination and, most strikingly, from post-vaccination BA.1 infections. To delineate the underlying antibody evasion mechanism, we determined the escaping mutation profiles2, epitope distribution3 and Omicron neutralization efficacy of 1640 RBD-directed neutralizing antibodies (NAbs), including 614 isolated from BA.1 convalescents. Interestingly, post-vaccination BA.1 infection mainly recalls wildtype-induced humoral memory. The resulting elicited antibodies could neutralize both wildtype and BA.1 and are enriched on non-ACE2-competing epitopes. However, most of these cross-reactive NAbs are heavily escaped by L452Q, L452R and F486V. BA.1 infection can also induce new clones of BA.1-specific antibodies that potently neutralize BA.1; nevertheless, these NAbs are largely escaped by BA.2/BA.4/BA.5 due to D405N and F486V, and react weakly to pre-Omicron variants, exhibiting poor neutralization breadths. As for therapeutic NAbs, Bebtelovimab4 and Cilgavimab5 can effectively neutralize BA.2.12.1 and BA.4/BA.5, while the S371F, D405N and R408S mutations would undermine most broad sarbecovirus NAbs. Together, our results indicate that Omicron may evolve mutations to evade the humoral immunity elicited by BA.1 infection, suggesting that BA.1-derived vaccine boosters may not achieve broad-spectrum protection against new Omicron variants.

10.
Zhongguo Zhong Yao Za Zhi ; 47(3): 730-736, 2022 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-35178956

RESUMO

The present study clarified the molecular mechanism of curcumol against liver fibrosis based on its effects on the autopha-gy and apoptosis of hepatic stellate cells. The hepatic stellate cells were divided into a blank control group, a transforming growth factor-ß1(TGF-ß1)(10 ng·mL~(-1)) group, and low-(12.5 mg·L~(-1)), medium-(25 mg·L~(-1)), and high-dose(50 mg·L~(-1)) curcumol groups. The effect of curcumol on the viability of hepatic stellate cells induced by TGF-ß1 was detected by the MTT assay kit. The apo-ptosis in each group was determined by flow cytometry. Real-time fluorescence-based quantitative PCR(RT-PCR) was employed for the detection of mRNA expression of α-smooth muscle actin(α-SMA), type Ⅰ collagen(collagen Ⅰ), and type Ⅲ collagen(collagen Ⅲ). Western blot was used to detect the protein expression of p62, microtubule-associated protein 1 light chain 3(LC3), beclin1, B cell lymphoma 2(Bcl-2), and Bcl-2-associated X protein(Bax). Transmission electron microscopy(TEM) was used to observe cell morphology and autophagosome formation in each group. The autophagic flux was observed after cell infection with adenovirus under double fluorescence labeling. The cell viability assay revealed that compared with the TGF-ß1 group, the curcumol groups showed significantly decreased cell viability. The apoptosis assay showed that the apoptosis rates of the curcumol groups were significantly higher than that of the TGF-ß1 group. RT-PCR indicated that the mRNA expression of α-SMA, collagenⅠ, and collagen Ⅲ in the curcumol groups was significantly lower than that of the TGF-ß1 group. Western blot showed that the expression of p62, LC3, beclin1, Bcl-2, and Bax in the curcumol groups was significantly different from that in the TGF-ß1 group. As demonstrated by TEM, compared with the TGF-ß1 group, the curcumol groups showed significantly increased autophagosomes. The detection of autophagic flow by the adenovirus under double fluorescence labeling showed that autolysosomes in the curcumol groups were significantly increased compared with those in the TGF-ß1 group. Curcumol can induce the autophagy and apoptosis of hepatic stellate cells, which may be one of its anti-liver fibrosis mechanisms.


Assuntos
Células Estreladas do Fígado , Fator de Crescimento Transformador beta1 , Actinas/genética , Actinas/metabolismo , Apoptose , Autofagia , Humanos , Fígado/metabolismo , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/genética , Cirrose Hepática/metabolismo , Sesquiterpenos , Fator de Crescimento Transformador beta1/metabolismo
11.
Proc Natl Acad Sci U S A ; 119(8)2022 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-35181607

RESUMO

Interface phonon modes that are generated by several atomic layers at the heterointerface play a major role in the interface thermal conductance for nanoscale high-power devices such as nitride-based high-electron-mobility transistors and light-emitting diodes. Here we measure the local phonon spectra across AlN/Si and AlN/Al interfaces using atomically resolved vibrational electron energy-loss spectroscopy in a scanning transmission electron microscope. At the AlN/Si interface, we observe various interface phonon modes, of which the extended and localized modes act as bridges to connect the bulk AlN modes and bulk Si modes and are expected to boost the phonon transport, thus substantially contributing to interface thermal conductance. In comparison, no such phonon bridge is observed at the AlN/Al interface, for which partially extended modes dominate the interface thermal conductivity. This work provides valuable insights into understanding the interfacial thermal transport in nitride semiconductors and useful guidance for thermal management via interface engineering.

12.
Preprint em Inglês | bioRxiv | ID: ppbiorxiv-479349

RESUMO

Omicron sub-lineage BA.2 has rapidly surged globally, accounting for over 60% of recent SARS-CoV-2 infections. Newly acquired RBD mutations and high transmission advantage over BA.1 urge the investigation of BA.2s immune evasion capability. Here, we show that BA.2 causes strong neutralization resistance, comparable to BA.1, in vaccinated individuals plasma. However, BA.2 displays more severe antibody evasion in BA.1 convalescents, and most prominently, in vaccinated SARS convalescents plasma, suggesting a substantial antigenicity difference between BA.2 and BA.1. To specify, we determined the escaping mutation profiles1,2 of 714 SARS-CoV-2 RBD neutralizing antibodies, including 241 broad sarbecovirus neutralizing antibodies isolated from SARS convalescents, and measured their neutralization efficacy against BA.1, BA.1.1, BA.2. Importantly, BA.2 specifically induces large-scale escape of BA.1/BA.1.1-effective broad sarbecovirus neutralizing antibodies via novel mutations T376A, D405N, and R408S. These sites were highly conserved across sarbecoviruses, suggesting that Omicron BA.2 arose from immune pressure selection instead of zoonotic spillover. Moreover, BA.2 reduces the efficacy of S309 (Sotrovimab)3,4 and broad sarbecovirus neutralizing antibodies targeting the similar epitope region, including BD55-5840. Structural comparisons of BD55-5840 in complexes with BA.1 and BA.2 spike suggest that BA.2 could hinder antibody binding through S371F-induced N343-glycan displacement. Intriguingly, the absence of G446S mutation in BA.2 enabled a proportion of 440-449 linear epitope targeting antibodies to retain neutralizing efficacy, including COV2-2130 (Cilgavimab)5. Together, we showed that BA.2 exhibits distinct antigenicity compared to BA.1 and provided a comprehensive profile of SARS-CoV-2 antibody escaping mutations. Our study offers critical insights into the humoral immune evading mechanism of current and future variants.

13.
Nano Lett ; 22(1): 476-484, 2022 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-34978815

RESUMO

A charge density wave (CDW) is a collective quantum phenomenon in metals and features a wavelike modulation of the conduction electron density. A microscopic understanding and experimental control of this many-body electronic state in atomically thin materials remain hot topics in materials physics. By means of material engineering, we realized a dimensionality and Zr intercalation induced semiconductor-metal phase transition in 1T-ZrX2 (X = Se, Te) ultrathin films, accompanied by a commensurate 2 × 2 CDW order. Furthermore, we observed a CDW energy gap of up to 22 meV around the Fermi level. Fourier-transformed scanning tunneling microscopy and angle-resolved photoemission spectroscopy reveal that 1T-ZrX2 films exhibit the simplest Fermi surface among the known CDW materials in TMDCs, consisting only of a Zr 4d derived elliptical electron conduction band at the corners of the Brillouin zone.

14.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-930256

RESUMO

Objective:To evaluate the risk factors for diaphragmatic dysfunction of patients with sepsis and septic shock, and the application value of bedside ultrasound.Methods:Patients with sepsis and septic shock in the Intensive Care Unit (ICU), General Hospital of Ningxia Medical University from January 2020 to May 2021 were prospectively recruited as the research subjects, general postoperative patients and healthy volunteers were admitted as postoperative control and normal control groups. General clinical data were collected, patients with sepsis and septic shock were dynamically observed high sensitive c-reactive protein (hs-CRP), interleukin-6 (IL-6), serum albumin, transferrin, prealbumin levels, blood lactate, Pcv-aCO 2, ScvO 2, etc.; and indirect calorimetry was used to measure the resting energy level of the patient to calculate the missing energy value. Bedside ultrasound was used to dynamically evaluate the changes of diaphragm excursion (DE),inspiratory diaphragm thickness, and expiratory diaphragm thickness, to calculate relevant parameters. DE<10 mm or diaphragmatic thickness fraction (DTF) < 20% was diagnosed as diaphragmatic dysfunction. Results:(1) On day 1 in the ICU, the DE of the septic shock group, sepsis group and postoperative control group were significantly lower than that in the normal control group [10.3 (9.0, 13.6) mm, 12.3 (9.1, 15.0) mm, 12.9 (10.5, 15.7) mm vs. 22.0 (16.0, 24.6) mm, all P<0.05], and the incidence of DTF<20% was significantly higher than in the normal control group (32.7%, 41.9%, 33.3% vs. 0 %, all P<0.05), and the incidence of DE<10 mm in the septic shock group and sepsis group was significantly higher than that of postoperative control group and normal control group (36.7%, 35.5% vs. 10.0%, 0%, respectively, all P<0.05). On day 7, the DE in the septic shock group was significantly lower than that in the sepsis group [10.5 (6.8, 13.5) mm vs. 14.4 (10.6, 18.6) mm, P<0.05].(2) Correlation analysis of each index: The DE of patients with sepsis and septic shock on day 1, 3, and 7 was negatively correlated with the hs-CRP ( r=-0.253, -0.436, -0.455, all P<0.05); On day 3, DE was also negatively correlated with IL-6 ( r=-0.338, P=0.009); and DTF was negatively correlated with hs-CRP ( r=-0.375, P=0.004). On day 1, there was a positive correlation between DTF and serum transferrin levels in patients with sepsis and septic shock ( r=0.221, P=0.049). On day 3 and 7, the DE was positively correlated with serum prealbumin levels ( r=0.318, 0.408, both P<0.05). Conclusions:Patients with sepsis and septic shock have developed diaphragmatic dysfunction on day 1 in the ICU, which is mainly manifested as decreased in diaphragm mobility and diaphragmatic thickness fraction, and is related to inflammation and high protein catabolism.

15.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-920381

RESUMO

Objective To understand the prevalence of osteoporosis and its influence factors in residents of Chongqing, and to provide the reference for osteoporosis prevention and treatment. Methods The data were from “An epidemiological survey of osteoporosis in Chongqing in 2018”, and the multi-stage stratified cluster random sampling method was used to select 1885 subjects (≥20 years old) from 32 villages/neighborhood committee in 4 areas (countries) of Chongqing. The investigation was performed by questionnaire (sociodemographic factors, lifestyle factors, history of orthopedics) and the bone mineral density was measured by QDR 4 500A dual energy X-ray absorptiometry. The chi-square test and multi factor multi-variant logistic regression analysis were utilized to analyze the data, the used software was SPSS 25.0. Results The morbidities of osteoporosis and osteopenia in residents (>20 years old) of Chongqing in China were 12.99% and 48.70%, respectively. The osteoporosis morbidity (19.08%) in females was significantly higher than that (4.42%) in males, and increased with age. The multi-variant logistic regression indicated that women (OR=6.10, 95% CI:4.08-9.14), the past medical history of fracture (OR=1.79, 95%CI:1.18-2.73) and age (OR=16.80, 95% CI:9.19-30.77) were risk factors for osteoporosis; milk intake (OR=0.65, 95%CI:0.47-0.89), overweight (OR=0.51, 95%CI:0.36-0.93)and obesity (OR=0.30, 95%CI:0.19-0.47), as compared with ≤primary school group, junior high school group (OR=0.57, 95%CI:0.39-0.82);≥high school group (0.40, 95%CI:0.26-0.61) were considered to be protective factors for osteoporosis. Conclusion The prevalence of osteoporosis among residents with age above 50 years old of Chongqing was very high. Health education and behavior intervention should be focused on the elderly or female residents to promote the formulation of healthy lifestyle.

16.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-928121

RESUMO

In order to explore the functions of genes of key rate-limiting enzymes chalcone isomerase(CHI) and chalcone synthase(CHS) in the biosynthesis of flavonoids in Lonicera macranthoides, this study screened and cloned the cDNA sequences of CHI and CHS genes from the transcriptome data of conventional variety and 'Xianglei' of L. macranthoides. Online bioinformatics analysis software was used to analyze the characteristics of the encoded proteins, and quantitative reverse-transcription polymerase chain reaction(qRT-PCR) to detect the expression of CHI and CHS in different parts of the varieties at different flowering stages. The content of luteo-loside was determined by high performance liquid chromatography(HPLC) and the correlation with the expression of the two genes was analyzed. The results showed that the CHI and CHS of the two varieties contained a 627 bp and 1170 bp open reading frame(ORF), respectively, and the CHI protein and CHS protein were stable, hydrophilic, and non-secretory. qRT-PCR results demonstrated that CHI and CHS of the two varieties were differentially expressed in stems and leaves at different flowering stages, particularly the key stages. Based on HPLC data, luteoloside content was in negative correlation with the relative expression of the genes. Thus, CHI and CHS might regulate the accumulation of flavonoids in L. macranthoides, and the specific functions should be further studied. This study cloned CHI and CHS in L. macranthoides and analyzed their expression for the first time, which laid a basis for investigating the molecular mechanism of the differences in flavonoids such as luteoloside in L. macranthoides and variety breeding.


Assuntos
Aciltransferases/metabolismo , Chalcona , Clonagem Molecular , Liases Intramoleculares , Lonicera/metabolismo , Melhoramento Vegetal
17.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-927956

RESUMO

The present study clarified the molecular mechanism of curcumol against liver fibrosis based on its effects on the autopha-gy and apoptosis of hepatic stellate cells. The hepatic stellate cells were divided into a blank control group, a transforming growth factor-β1(TGF-β1)(10 ng·mL~(-1)) group, and low-(12.5 mg·L~(-1)), medium-(25 mg·L~(-1)), and high-dose(50 mg·L~(-1)) curcumol groups. The effect of curcumol on the viability of hepatic stellate cells induced by TGF-β1 was detected by the MTT assay kit. The apo-ptosis in each group was determined by flow cytometry. Real-time fluorescence-based quantitative PCR(RT-PCR) was employed for the detection of mRNA expression of α-smooth muscle actin(α-SMA), type Ⅰ collagen(collagen Ⅰ), and type Ⅲ collagen(collagen Ⅲ). Western blot was used to detect the protein expression of p62, microtubule-associated protein 1 light chain 3(LC3), beclin1, B cell lymphoma 2(Bcl-2), and Bcl-2-associated X protein(Bax). Transmission electron microscopy(TEM) was used to observe cell morphology and autophagosome formation in each group. The autophagic flux was observed after cell infection with adenovirus under double fluorescence labeling. The cell viability assay revealed that compared with the TGF-β1 group, the curcumol groups showed significantly decreased cell viability. The apoptosis assay showed that the apoptosis rates of the curcumol groups were significantly higher than that of the TGF-β1 group. RT-PCR indicated that the mRNA expression of α-SMA, collagenⅠ, and collagen Ⅲ in the curcumol groups was significantly lower than that of the TGF-β1 group. Western blot showed that the expression of p62, LC3, beclin1, Bcl-2, and Bax in the curcumol groups was significantly different from that in the TGF-β1 group. As demonstrated by TEM, compared with the TGF-β1 group, the curcumol groups showed significantly increased autophagosomes. The detection of autophagic flow by the adenovirus under double fluorescence labeling showed that autolysosomes in the curcumol groups were significantly increased compared with those in the TGF-β1 group. Curcumol can induce the autophagy and apoptosis of hepatic stellate cells, which may be one of its anti-liver fibrosis mechanisms.


Assuntos
Humanos , Actinas/metabolismo , Apoptose , Autofagia , Células Estreladas do Fígado , Fígado/metabolismo , Cirrose Hepática/metabolismo , Sesquiterpenos , Fator de Crescimento Transformador beta1/metabolismo
18.
Photodiagnosis Photodyn Ther ; 36: 102568, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34614424

RESUMO

BACKGROUND: Although hemoporfin photodynamic therapy is a promising treatment approach for port-wine stains, its efficacy in children has not been sufficiently assessed. We aimed to evaluate the efficacy and safety of this approach in a paediatric population. METHODS: We retrospectively analysed the medical records of 439 children with port-wine stains receiving hemoporfin photodynamic therapy at our institution from July 2017 to January 2020. They received intravenous hemoporfin (hematoporphyrin monomethyl ether, 5 mg/kg), followed by lesion irradiation with a 532-nm green LED light for 20-25 min. The stains' blanching degree and occurrence of adverse events were registered. RESULTS: Overall, 95.2% of patients showed an 'effective response' (>20% fading) and 74.3% showed almost-complete resolution and great improvement (≥60% fading). Red and pink lesions showed better response than purple lesions (P < 0.05). Neck and facial lesions showed better response than the trunk and extremity lesions (P < 0.05). The response of the patients to the PDT showed a cumulative effect of the treatment session. No photosensitivity or systemic adverse reactions were observed. Transient local adverse effects included swelling, purpura, crusts, and pigmentation, which resolved without treatment. Only 2% of children had permanent scars, likely related to scratching crusts. CONCLUSIONS: Hemoporfin photodynamic therapy was well tolerated and effective in paediatric Chinese patients with port-wine stains. It could be recommended as the first choice, over pulsed-dye laser therapy, for treating port-wine stains, particularly for large lesions. This should be evaluated in direct clinical trials.


Assuntos
Fotoquimioterapia , Mancha Vinho do Porto , Criança , Hematoporfirinas , Humanos , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/uso terapêutico , Mancha Vinho do Porto/tratamento farmacológico , Estudos Retrospectivos , Resultado do Tratamento
19.
Eur J Pharmacol ; 908: 174351, 2021 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-34280397

RESUMO

Thymosin beta 4 (Tß4) can improve the liver fibrosis and reduce inflammation, while the role of Tß4 in non-alcoholic fatty liver disease (NAFLD) whether mediated by ferroptosis remains unclear. A rat model of NAFLD was established on a high-fat diet (HFD), and rats were assigned ferroptosis inducer erastin and inhibitor Ferrostatin 1 (Fer-1). Subsequently, histopathology of the liver and the expression of ferroptosis-related genes in rat liver were detected. The steatosis of LO2 cells was induced by palmitic acid (PA) to reproduce the results of the rat experiment. The small interfering RNA (siRNA) was used to interfere with GPX4 expression to explore the influence on Tß4 function. Tß4 improved the inflammation, biochemical and lipid metabolism indexes, increased the antioxidant level, and inhibited abnormal accumulation of intracellular reactive oxygen species in HFD-induced NAFLD rats. Also, Tß4 improved PA-induced LO2 damage and inhibited apoptosis of PA-induced LO2 cells. Both in vivo and in vitro, Tß4 regulated expression of genes associated with ferroptosis, and Fer-1 treatment exaggerated the above effects of Tß4, while erastin attenuated the protective effect of Tß4. Moreover, siRNA GPX4 attenuated the protective effect of Tß4 on the rat liver and on the mitochondrial membrane integrity of LO2 cells. Interfered expression of GPX4 with siRNA also regulated the expression of Bcl-2, Bax, Caspase-3 and SOD1, which attenuated therapeutic effect of Tß4 on rat liver and LO2 cells. This study revealed that Tß4 protects hepatocytes by inhibiting the GPX4-mediated ferroptosis pathway, which provides a new strategy and target for the treatment of NAFLD.


Assuntos
Ferroptose , Animais , Hepatopatia Gordurosa não Alcoólica , Ratos , Timosina , Regulação para Cima
20.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 29(3): 797-804, 2021 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-34105475

RESUMO

OBJECTIVE: To investigate the effects of autophagy inhibitor ROC-325 and its combination with bortezomib on the proliferation, apoptosis and autophagy of multiple myeloma cell lines. METHODS: Multiple myeloma cells were treated with ROC-325 at different concentration. The cell proliferation was detected by CCK-8. Apoptosis was determined by Caspase-3/7 and Caspase-9 activity assays. Autophagy was detected by monodansylcadaverine staining. The apoptosis-related proteins (PARP and Caspase-3) and autophagy-related proteins (P62, Beclin-1, and LC3A/B) were analyzed by Western blot. The combined effect with bortezomib on bortezomib-resistant cell line was detected by CCK-8. RESULTS: ROC-325 inhibited the proliferation of RPMI 8226, RPMI 8226-BTZ100, U266 and IM9 cells in a dose-dependent manner (r=-0.8275, r=-0.9079, r=-0.9422, r=-0.9305), the 72 h IC50 values were 2.795, 4.020, 5.432 and 4.755 µmol/L, respectively. The activity assays of Caspase-3/7 and Caspase-9 showed that their relative activity was increased gradually in proportion to the drug concentration with the statistically significant difference (r=0.9648, r=0.9377, r=0.9318; r=0.9087, r=0.9431, r=0.8914). MDC staining results showed that the number of autophagic vacuoles increased with the rise of ROC-325 concentration (r=0.9565, r=0.9373, r=0.9233). ROC-325 could increase the expression of apoptosis-related proteins (PARP and Caspase-3) and autophagy-related proteins (P62 and LC3-Ⅱ/LC3-Ⅰ), but decrease the expression of Beclin-1 detected by Western blot. The CCK-8 assay showed that ROC-325 combined with bortezomib had synergistic effect on the inhibition of drug resistant cell line RPMI 8226-BTZ100. CONCLUSION: ROC-325 can inhibit the proliferation, induce the apoptosis of myeloma cells through the mitochondrial pathway, inhibit the autophagy of myeloma cells by affecting the fusion of autophagosomes and lysosomes, and overcome bortezomib resistance by the combination of ROC-325 with bortezomib.


Assuntos
Mieloma Múltiplo , Apoptose , Autofagia , Bortezomib/farmacologia , Linhagem Celular Tumoral , Proliferação de Células , Humanos , Hidroxicloroquina/análogos & derivados
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