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1.
Phys Rev Lett ; 131(18): 186703, 2023 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-37977650

RESUMO

The understanding and manipulation of anisotropic Gilbert damping is crucial for both fundamental research and versatile engineering and optimization. Although several works on anisotropic damping have been reported, no direct relationship between the band structure and anisotropic damping was established. Here, we observed an anisotropic damping in Fe/GeTe manipulated by the symmetric band structures of GeTe via angle-resolved photoemission spectroscopy. Moreover, the anisotropic damping can be modified by the symmetry of band structures. Our Letter provides insightful understandings of the anisotropic Gilbert damping in ferromagnets interfaced with Rashba semiconductors and suggests the possibility of manipulating the Gilbert damping by band engineering.

2.
J Pept Sci ; 29(11): e3497, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37088557

RESUMO

Antimicrobial peptides and their analogues have become substitutes for antibiotics in recent years. The antimicrobial peptide analogue SAMP-A4-C8 (n-octanoic-VRLLRRRI) with high antimicrobial activity was found in our lab. We speculate that it may kill pathogens by some lethal mechanism of action. In the present investigation, the microbicidal activities of SAMP-A4-C8 and its mechanism of action were investigated. The results demonstrated that SAMP-A4-C8 had lethal activities against Staphylococcus aureus and Candida albicans by cell disruption. Based on its microbicidal activities, we believe that it is worth further research for its potential as drug candidate. The results showed that SAMP-A4-C8, with low propensity to induce the resistance of S. aureus and C. albicans, could kill the persister cells of S. aureus and C. albicans, exhibited biofilm forming inhibition activity and preformed biofilm eradication ability against S. aureus and C. albicans, and displayed therapeutic potential on pneumonia in S. aureus-infected mice by reducing lung inflammation. The present study provided a promising drug candidate in the war against multidrug resistance.


Assuntos
Anti-Infecciosos , Infecções Estafilocócicas , Animais , Camundongos , Staphylococcus aureus , Peptídeos Antimicrobianos , Anti-Infecciosos/farmacologia , Antibacterianos/farmacologia , Candida albicans , Biofilmes , Testes de Sensibilidade Microbiana
3.
Beijing Da Xue Xue Bao Yi Xue Ban ; 55(5): 871-875, 2023 Oct 18.
Artigo em Chinês | MEDLINE | ID: mdl-37807742

RESUMO

OBJECTIVE: To investigate the status quo of recognition and management of renal colic among urological surgeons in China. METHODS: From November 2021 to March 2022, 725 urological surgeons in China were surveyed in the form of a questionnaire, including their province, hospital grade, professional title, the number of patients with renal colic treated per week, the preferred drugs and the cognition of the disease. This study was approved by the Medical Ethics Committee of Peking University People's Hospital, and all respondents completed informed consent online. RESULTS: During November 2021 and March 2022, urological surgeons across China were surveyed in the form of a questionnaire, and the reliability and validity of the questionnaire were verified before the study was carried out. In the study, 720 valid questionnaires were collected (accounting for 99.31% of the total number), in which 42.4% of the doctors' preferred drugs were non-steroidal anti-inflammatory drugs (NSAIDs), and 40.0% of the doctors' preferred antispasmodic drugs. Opioids were the first choice of 11.0% of the physicians and other treatments were preferred by 6.6% of physicians. In addition, 61.1% of the doctors thought that the mechanism of renal colic was elevated prostaglandin, 32.2% thought it was ureteral spasm, 5.0% thought it was calculi irritation, and 1.7% thought the mechanism was unclear. The doctor of the cognition of the generation mechanism of renal colic pain had a significant influence on the preferred treatment option (χ2=54.399, P < 0.001) that the "elevated prostaglandins" doctor more often preferred NSAIDs than the doctor who thought cramps and ureter stones caused renal colic (51.6% vs. 28.0%, χ2=34.356, P < 0.001;51.6% vs. 19.4%, χ2=13.759, P < 0.001). In addition, hospital class, physician title, and the number of weekly consultations by physicians influenced the choice of medications for renal colic (P < 0.05), tertiary hospitals, middle and senior professional titles and weekly patients with renal colic > 8 cases generally preferred NSAIDs. CONCLUSION: There are deficiencies in the cognition and drug treatment of renal colic among urological surgeons in China. The choice of the preferred drug was related to the doctor's cognition of the disease, the grade of the hospital, the doctor's professional title and the weekly treatment volume.


Assuntos
Cólica Renal , Humanos , Cólica Renal/tratamento farmacológico , Urologistas , População do Leste Asiático , Reprodutibilidade dos Testes , Anti-Inflamatórios não Esteroides , Inquéritos e Questionários
4.
J Integr Neurosci ; 20(1): 137-142, 2021 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-33834701

RESUMO

Pentraxin 3 is considered an important inflammatory marker is known to increase in patients with ischemic stroke, but the relationship between pentraxin 3 and intracerebral hemorrhage mortality is unclear. The purpose of this study is to investigate the level of pentraxin 3 in serum and its impact on prognosis in 307 patients with intracerebral hemorrhage. During the 5-year follow-up, the mortality rate of patients with intracerebral hemorrhage was 22.5%. The serum pentraxin 3 level of the brain-dead patients was higher than that of the control group (P < 0.05). Logistic regression analysis indicated a high correlation between the pentraxin 3 level and the mortality rate 95% (hazard ratio: 3.671; confidence interval: 1.558-4.297). The receiver operating characteristic curve showed that pentraxin 3 (Area Under Curve = 0.801) had a higher diagnostic value than C-reactive protein (Area Under Curve = 0.701). The pentraxin 3 level increased significantly after intracerebral hemorrhage and has an important predictive value for a prognosis for intracerebral hemorrhage mortality.


Assuntos
Morte Encefálica/sangue , Proteína C-Reativa/metabolismo , Hemorragia Cerebral/sangue , Hemorragia Cerebral/diagnóstico , Hemorragia Cerebral/mortalidade , Componente Amiloide P Sérico/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico
5.
Biochem J ; 476(20): 3069-3080, 2019 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-31652303

RESUMO

CGA-N9, a peptide derived from human chromogranin A (CGA), was found to have antimicrobial activity in our previous investigation, but its mechanism of action remains unclear. Herein, the mechanism of action of CGA-N9 was investigated. We found that CGA-N9 induced the depolarization of the cell membrane and uptake of calcium ions into the cytosol and mitochondria. With the disruption of the mitochondrial membrane potential, the generation of intracellular reactive oxygen species (ROS) increased. Accordingly, we assessed apoptotic processes in Candida tropicalis cells post-treatment with CGA-N9 and found cytochrome c leakage, chromatin condensation and DNA degradation. The interaction of CGA-N9 with DNA in vitro showed that CGA-N9 did not degrade DNA but bound to DNA via an electrostatic interaction. In conclusion, CGA-N9 exhibits antifungal activity by inducing apoptosis in C. tropicalis.


Assuntos
Antifúngicos/farmacologia , Apoptose/efeitos dos fármacos , Candida tropicalis/efeitos dos fármacos , Candida tropicalis/metabolismo , Cromogranina A/química , Fragmentos de Peptídeos/farmacologia , Antifúngicos/metabolismo , Cálcio/metabolismo , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Cromatina/metabolismo , Cromogranina A/metabolismo , Cromogranina A/farmacologia , Citocromos c/metabolismo , Citosol/metabolismo , Fragmentação do DNA/efeitos dos fármacos , DNA Fúngico/metabolismo , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/metabolismo , Fragmentos de Peptídeos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Eletricidade Estática
6.
Vascul Pharmacol ; 153: 107216, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37699495

RESUMO

Pulmonary arterial hypertension (PAH) is a complex and progressive disease characterized by pulmonary arterial remodeling. Despite that current combination therapy has shown improvement in morbidity and mortality, a better deciphering of the underlying pathological mechanisms and novel therapeutic targets is urgently needed to combat PAH. MicroRNA, the critical element in post-transcription mechanisms, mediates cellular functions mainly by tuning downstream target gene expression. Meanwhile, upstream regulators can regulate miRNAs in synthesis, transcription, and function. In vivo and in vitro studies have suggested that miRNAs and their regulators are involved in PAH. However, the miRNA-related regulatory mechanisms governing pulmonary vascular remodeling and right ventricular dysfunction remain elusive. Hence, this review summarized the controversial roles of miRNAs in PAH pathogenesis, focused on different miRNA-upstream regulators, including transcription factors, regulatory networks, and environmental stimuli, and finally proposed the prospects and challenges for the therapeutic application of miRNAs and their regulators in PAH treatment.


Assuntos
Hipertensão Pulmonar , MicroRNAs , Hipertensão Arterial Pulmonar , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Hipertensão Arterial Pulmonar/tratamento farmacológico , Hipertensão Arterial Pulmonar/genética , Hipertensão Arterial Pulmonar/metabolismo , Hipertensão Pulmonar/tratamento farmacológico , Hipertensão Pulmonar/genética , Pulmão/patologia , Fatores de Transcrição/metabolismo , Remodelação Vascular , Artéria Pulmonar
7.
Adv Mater ; 35(9): e2208343, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36617232

RESUMO

Dual topological insulators, simultaneously protected by time-reversal symmetry and crystalline symmetry, open great opportunities to explore different symmetry-protected metallic surface states. However, the conventional dual topological states located on different facets hinder integration into planar opto-electronic/spintronic devices. Here, dual topological superlattices (TSLs) Bi2 Se3 -(Bi2 /Bi2 Se3 )N with limited stacking layer number N are constructed. Angle-resolved photoelectron emission spectra of the TSLs identify the coexistence and adjustment of dual topological surface states on Bi2 Se3 facet. The existence and tunability of spin-polarized dual-topological bands with N on Bi2 Se3 facet result in an unconventionally weak antilocalization effect (WAL) with variable WAL coefficient α (maximum close to 3/2) from quantum transport experiments. Most importantly, it is identified that the spin-polarized surface electrons from dual topological bands exhibit circularly and linearly polarized photogalvanic effect (CPGE and LPGE). It is anticipated that the stacked dual-topology and stacking layer number controlled bands evolution provide a platform for realizing intrinsic CPGE and LPGE. The results show that the surface electronic structure of the dual TSLs is highly tunable and well-regulated for quantum transport and photoexcitation, which shed light on engineering for opto-electronic/spintronic applications.

8.
Mar Genomics ; 64: 100969, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35811107

RESUMO

Members of the genus Devosia are known for their abilities to degrade deoxynivalenol (DON). The type strain Devosia beringensis S02T (= JCM 33772 = CCTCC AB 2019343) was isolated from sediment of the Bering Sea and identified in 2021. However, the genome sequence of D. beringensis S02T remains unclear, which complicates the exploration into the function and ecological role of this strain in marine sediment. The genome of D. beringensis S02T contained a 4,048,765 bp chromosome with a G + C content of 63.84 mol%. Potential genes involved in DON degradation were found in the genome. In addition, multiple genes involved in polysaccharide degradation, including agarose, chitin, carrageen, pectate, starch, and xylan, were also annotated in the genome. These findings indicated the potential of strain S02T to be used for DON degradation and its ecological function in the carbon cycle in marine sediment.


Assuntos
Hyphomicrobiaceae , DNA Bacteriano/genética , Hyphomicrobiaceae/genética , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Tricotecenos
9.
Zhonghua Gan Zang Bing Za Zhi ; 19(9): 686-91, 2011 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-22152385

RESUMO

OBJECTIVE: To investigate the effect of 5-FU (5-fluorouracil) on enriching cancer stem cells of HCC cell line BEL-7402 and the biological characteristics of enriched cells. METHODS: The enriching concentration of 5-FU was determined by CCK-8 (cell counting kit-8). Flow Cytometry was used to determine the changes in cell cycle and positive expression ratio of surface marker CD56, CD54, EpCAM and CD133. The self-renewal and differentiation of positive cells were tested by colony formation assay, and were compared with the control group. RESULTS: Enriching concentration of 5-FU was determined as 10 µg/ml with 48 h incubation. After enrichment, G0/G1 phase cells increased from 57.50 %+/-0.98% to 68.70%+/-3.41% (P<0.05). Whereas S phase cells decreased from 40.26%+/-4.12% to 31.80%+/-4.15% (P<0.01); G2/M phase cells disappeared in experimental group, and was 5.80%+/-1.87% in control group (P<0.01). The proportion of the cell cycle changed with significant statistical differences. Meanwhile, positive rate of cell surface makers CD56, CD54, EpCAM and CD133 increased from 0.57%+/-0.12%, 8.10%+/-6.79%, 0.3%+/-0.01% and 3.20%+/-0.99% to 4.13%+/-0.06%, 50.08%+/-1.69%, 0.55%+/-0.07% and 10.51%+/-1.13%, respectively. The difference was significant (P<0.05). The colony forming ratio of CD56, CD54, EpCAM and CD133 negative cells and positive cells were 2.11%+/-0.21%, 3.32%+/-0.31%; 0.86%+/-0.101%, 2.40%+/-0.52 %; 7.19%+/-0.56%, 7.73%+/-0.71%; 2.70%+/-0.26%, 5.75%+/-0.81%, respectively, and significant differences were found between (P<0.05). CONCLUSION: 5-fluorouracil enriched the cancer stem cell population in HCC cell line BEL-7402. CD56 and CD54 can be used as important surface markers in research of liver cancer stem cells.


Assuntos
Fluoruracila/farmacologia , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/metabolismo , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Células-Tronco Neoplásicas/citologia
10.
Genes Genet Syst ; 95(5): 275-279, 2021 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-33328391

RESUMO

Primula denticulata exhibits considerable variation in floral morphology and flowering phenology along elevational gradients in SW China. We isolated 30 microsatellite markers from P. denticulata to facilitate further investigation of population genetics and floral evolution in this species. We used the HiSeq X-Ten sequencing system to develop a set of markers, and measured polymorphism and genetic diversity in a sample of 72 individuals from three natural populations of P. denticulata subsp. denticulata. The markers displayed relatively high polymorphism, with the number of alleles ranging from two to seven (mean = 3.567). The observed and expected heterozygosity ranged from 0 to 1.000 and 0.041 to 0.702, respectively. Twenty-eight of the loci were also successfully amplified in P. denticulata subsp. sinodenticulata. The microsatellite markers we have identified will provide valuable tools for investigations of the population genetic structure, mating systems and phylogeography of the P. denticulata complex, and will help to address questions concerning the ecological and genetic mechanisms responsible for the evolution of reproductive traits in the species.


Assuntos
Repetições de Microssatélites , Primula/genética , Genoma de Planta , Polimorfismo Genético
11.
Artigo em Chinês | WPRIM | ID: wpr-1010143

RESUMO

OBJECTIVE@#To investigate the status quo of recognition and management of renal colic among urological surgeons in China.@*METHODS@#From November 2021 to March 2022, 725 urological surgeons in China were surveyed in the form of a questionnaire, including their province, hospital grade, professional title, the number of patients with renal colic treated per week, the preferred drugs and the cognition of the disease. This study was approved by the Medical Ethics Committee of Peking University People's Hospital, and all respondents completed informed consent online.@*RESULTS@#During November 2021 and March 2022, urological surgeons across China were surveyed in the form of a questionnaire, and the reliability and validity of the questionnaire were verified before the study was carried out. In the study, 720 valid questionnaires were collected (accounting for 99.31% of the total number), in which 42.4% of the doctors' preferred drugs were non-steroidal anti-inflammatory drugs (NSAIDs), and 40.0% of the doctors' preferred antispasmodic drugs. Opioids were the first choice of 11.0% of the physicians and other treatments were preferred by 6.6% of physicians. In addition, 61.1% of the doctors thought that the mechanism of renal colic was elevated prostaglandin, 32.2% thought it was ureteral spasm, 5.0% thought it was calculi irritation, and 1.7% thought the mechanism was unclear. The doctor of the cognition of the generation mechanism of renal colic pain had a significant influence on the preferred treatment option (χ2=54.399, P < 0.001) that the "elevated prostaglandins" doctor more often preferred NSAIDs than the doctor who thought cramps and ureter stones caused renal colic (51.6% vs. 28.0%, χ2=34.356, P < 0.001;51.6% vs. 19.4%, χ2=13.759, P < 0.001). In addition, hospital class, physician title, and the number of weekly consultations by physicians influenced the choice of medications for renal colic (P < 0.05), tertiary hospitals, middle and senior professional titles and weekly patients with renal colic > 8 cases generally preferred NSAIDs.@*CONCLUSION@#There are deficiencies in the cognition and drug treatment of renal colic among urological surgeons in China. The choice of the preferred drug was related to the doctor's cognition of the disease, the grade of the hospital, the doctor's professional title and the weekly treatment volume.


Assuntos
Humanos , Cólica Renal/tratamento farmacológico , Urologistas , População do Leste Asiático , Reprodutibilidade dos Testes , Anti-Inflamatórios não Esteroides , Inquéritos e Questionários
12.
Chinese Journal of Ultrasonography ; (12): 1029-1033, 2017.
Artigo em Chinês | WPRIM | ID: wpr-707605

RESUMO

Objective To evaluate the value of superb micro-vascular imaging(SMI) in the detection of TI-RADS 4 thyroid nodules . Methods A retrospective analysis of 61 patients( 68 thyroid nodules) with grade 4 TI-RADS diagnosed by routine ultrasound and undergone SMI were performed ,and the differences between CDFI and SMI were compared . The TI-RADS level were corrected by CDFI and SMI technology , combined with the pathological results to compare the diagnostic efficacy before and after the correction . At the same time ,the related factors had been collected to evaluate the risk factors and to compare the value of SMI in benign and malignant nodules . Results SMI was more likely to detect the type Ⅲ blood flow ( P =0 .001) of malignant nodules . The area under the ROC curve before TI-RADS correction ,after CDFI correction and SMI correction were 0 .66 ,0 .69 and 0 .78 ,respectively . Compared with before TI-RADS correction and after CDFI correction ,the area under the curve of SMI correction was significant different ( P=0 .002 ,0 .009) . There was no significant difference in the area under the curve between after CDFI correction and before correction ( P = 0 .4196 ) . The sensitivity of SMI was higher ,but there was no significant difference ( P >0 .05) . After single factor analysis and multivariate analysis ,central blood flow and perforating blood flow found by SMI were not independent risk factors for thyroid cancer . Conclusions SMI is more effective than CDFI in detecting TI-RADS 4 thyroid nodules ,and it is expected to be an auxiliary tool for the diagnosis of benign and malignant thyroid nodules .

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