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1.
Bioact Mater ; 20: 339-354, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35784639

RESUMO

Myocardial infarction (MI) leads to massive cardiomyocyte death and deposition of collagen fibers. This fibrous tissue disrupts electrical signaling in the myocardium, leading to cardiac systolic and diastolic dysfunction, as well as arrhythmias. Conductive hydrogels are a promising therapeutic strategy for MI. Here, we prepared a highly water-soluble conductive material (GP) by grafting polypyrrole (PPy) onto non-conductive gelatin. This component was added to the gel system formed by the Schiff base reaction between oxidized xanthan gum (OXG) and gelatin to construct an injectable conductive hydrogel. The prepared self-healing OGGP3 (3 wt% GP) hydrogel had good biocompatibility, elastic modulus, and electrical conductivity that matched the natural heart. The prepared biomaterials were injected into the rat myocardial scar tissue 2 days after MI. We found that the cardiac function of the rats treated with OGGP3 was improved, making it more difficult to induce arrhythmias. The electrical resistivity of myocardial fibrous tissue was reduced, and the conduction velocity of myocardial tissue was increased. Histological analysis showed reduced infarct size, increased left ventricular wall thickness, increased vessel density, and decreased inflammatory response in the infarcted area. Our findings clearly demonstrate that the OGGP3 hydrogel attenuates ventricular remodeling and inhibits infarct dilation, thus showing its potential for the treatment of MI.

2.
Int J Public Health ; 67: 1604979, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36090824

RESUMO

Objectives: The study aimed at analyzing the prevalence of five psychological outcomes (depression, anxiety, stress, post-traumatic stress disorder (PTSD), and suicidal ideation) among Chinese healthcare workers (HCWs), and measured the total possible negative psychological impact 1 year after the COVID-19 initial outbreak. Methods: A cross-sectional nationwide multi-center study was performed between November 2020 and March 2021 in China. A self-report questionnaire was applied, and three psychological scales were used. Binary logistic regression was performed to analyze the risk factors associated with each psychological outcome. Results: The findings demonstrated that the COVID-19 pandemic had a negative psychological impact on HCWs, which was still evident 1 year after the initial outbreak. Nurses showed higher depression and anxiety than other HCWs. Female gender, passive coping, long working hours, having a chronic disease, and experiencing violence, among other factors, were all risk factors for psychological impairment. Conclusion: Developing and promoting programs to improve mental health among HCWs, and identifying those who might need psychological support is still relevant 1 year after the initial outbreak.


Assuntos
COVID-19 , COVID-19/epidemiologia , China/epidemiologia , Estudos Transversais , Surtos de Doenças , Feminino , Pessoal de Saúde , Humanos , Pandemias
3.
Chem Biodivers ; 2022 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-36098055

RESUMO

Two new C 21 steroidal glycosides, brapreguane A and B ( 1 - 2 ) were isolated from 75% aqueous ethanol extract of Selaginella braunii Baker. Their structures were established by spectroscopic analyses (1D/2D NMR spectra and HRESIMS). The absolute configurations of sugar were elucidated by enzymatic hydrolysis and GCMS analysis. In addition, all compounds were evaluated for the anti-proliferative activities against various human cancer cells in vitro . Compounds exhibited no inhibition to various human cancer cells.

4.
Zhongguo Dang Dai Er Ke Za Zhi ; 24(9): 1036-1041, 2022.
Artigo em Chinês | MEDLINE | ID: mdl-36111723

RESUMO

OBJECTIVES: To study the clinical features of children with rhabdomyosarcoma (RMS) and the influencing factors for prognosis. METHODS: A retrospective analysis was performed on the clinical and follow-up data of 20 children with RMS who were admitted to the Department of Pediatric Hematology, Xiangya Hospital of Central South University, from June 2014 to September 2020. RESULTS: The most common clinical symptoms of the 20 children with RMS at the first visit were painless mass (13/20, 65%), exophthalmos (4/20, 20%), and abdominal pain (3/20, 15%). According to the staging criteria of Intergroup Rhabdomyosarcoma Study Group (IRSG), there was 1 child (5%) with stage I RMS, 4 (20%) with stage II RMS, 9 (45%) with stage III RMS, and 6 (30%) with stage IV RMS. The median follow-up time was 19 months for the 20 children (range: 3-93 months), with a 2-year overall survival (OS) rate of 79.5% (95%CI: 20.1-24.3) and a 2-year event-free survival (EFS) rate of 72.0% (95%CI: 19.5-23.9). Pleomorphic RMS was associated with the reduced 2-year OS rate (P<0.05), and distant metastasis, IRSG stage IV RMS, and high-risk RMS were associated with the reduced 2-year EFS rate (P<0.05). CONCLUSIONS: RMS has no specific clinical symptoms at the first visit, with painless mass as the most common symptom. Distant metastasis, IRSG stage, and risk degree may be associated with the prognosis of children with RMS.


Assuntos
Rabdomiossarcoma Embrionário , Rabdomiossarcoma , Criança , Humanos , Prognóstico , Estudos Retrospectivos , Rabdomiossarcoma/diagnóstico , Rabdomiossarcoma/terapia , Taxa de Sobrevida
5.
ACS Biomater Sci Eng ; 2022 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-36121432

RESUMO

We report the design and characterization of pH-responsive polymer coatings that enable catheter balloon-mediated transfer of DNA to arterial tissue in short, clinically relevant inflation times. Our approach exploits the pH-dependent ionization of poly(acrylic acid) (PAA) to promote disassembly and release of plasmid DNA from polyelectrolyte multilayers. We characterized the contact transfer of multilayers composed of PAA, plasmid DNA, and linear poly(ethyleneimine) (LPEI) identified as promising in prior studies on the delivery of DNA to arterial tissue. In contrast to thinner films evaluated previously, we found thicker coatings composed of 32 repeating (LPEI/PAA/LPEI/DNA)x tetralayers to swell substantially in physiologically relevant media (in PBS; pH = 7.4). In some cases, these coatings also disintegrated or delaminated rapidly from their underlying substrates, suggesting the potential for enhanced balloon-mediated transfer. We developed a technically straightforward agarose gel-based hole-insertion model to characterize factors (inflation time, lumen size, etc.) that influence contact transfer of DNA when film-coated balloons are inflated into contact with soft surfaces. Those studies and the results of in vivo experiments using small animal (rat) and large animal (pig) models of peripheral arterial injury revealed catheters coated with these materials to promote robust contact transfer of DNA to soft hydrogel surfaces and the luminal surfaces of arterial tissue using inflation times as short as 30 s. These short inflation times are relevant in the context of clinical vascular interventions in peripheral arteries. Additional studies demonstrated that contact transfer of DNA using these short times can promote subsequent dissemination and transport of DNA to the medial tissue layer, suggesting the potential for use in therapeutically relevant applications of balloon-mediated gene transfer.

6.
ACS Appl Mater Interfaces ; 14(37): 42645-42655, 2022 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-36095298

RESUMO

It is important for the floor of railroad cars to be fitted with vibration- and noise-reducing, fire-resistant, and durable materials. In this study, inspired by a delicate and ordered bamboo gradient structure and excellent multilevel interfaces, we fabricated a laminated composite with characteristics similar to those of the bamboo structure using a simple and effective "top-down" method by laminating fast-growing wood, waste rubber, and bamboo charcoal plastic sheets made of bamboo processing residues. This composite material combines the unique advantages of a laminated structure design and composite interface bionics. The low density (0.73 g/cm3) of the laminated composite results in a specific modulus of 13.03 GPa cm3/g, a vibration damping ratio of 6.61%, and an impact toughness of 14.16 J/cm2, which is significantly higher than that of other wood-based composites used for high-speed rail floors, such as Birch plywood (BP). In addition, we also investigated the laminated composite bonding property, fire resistance, and fatigue performance. This biomimetic bamboo-wood composite material has great potential for application in fitting the floor of eco-friendly railway cars.

7.
Diabetes Care ; 2022 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-36126158

RESUMO

OBJECTIVE: Patients with type 2 diabetes are at higher risk for fracture risk because of attenuated bone turnover and impaired bone microarchitecture. The comparative effect of warfarin over non-vitamin K antagonist oral anticoagulants (NOACs) on incident fractures among patients with type 2 diabetes comorbid with atrial fibrillation (AF) remains to be elucidated. RESEARCH DESIGN AND METHODS: This was a retrospective, propensity score-weighted, population-based cohort study of adults with type 2 diabetes and AF who were started on warfarin or NOAC between 2005 and 2019 identified from an electronic database of the Hong Kong Hospital Authority. The primary outcome was a composite of major osteoporotic fractures (hip, clinical vertebral, proximal humerus, and wrist). Hazard ratios (HRs) were calculated using Cox proportional hazards regression models. RESULTS: A total of 15,770 patients with type 2 diabetes comorbid with AF were included (9,288 on NOAC, 6,482 on warfarin). During a median follow-up of 20 months, 551 patients (3.5%) sustained major osteoporotic fractures (201 [2.2%] in the NOAC group, 350 [5.4%] in the warfarin group). The adjusted cumulative incidence was lower among NOAC users than warfarin users (HR 0.80; 95% CI 0.64, 0.99; P = 0.044). Subgroup analyses showed consistent protective effects against major osteoporotic fractures among NOAC users across sex, age, HbA1c, duration of diabetes, and history of severe hypoglycemia compared with warfarin users. CONCLUSIONS: NOAC use was associated with a lower risk of major osteoporotic fractures than warfarin use among patients with type 2 diabetes comorbid with AF. NOAC may be the preferred anticoagulant from the perspective of bone health.

8.
Artigo em Inglês | MEDLINE | ID: mdl-36125502

RESUMO

Background: This study aims to systematically evaluate the association between metabolic syndrome (MS) and pulmonary function through meta-analysis. Methods: Electronic databases, including PubMed, Embase, Web of Science, and Cochrane Library, were systematically searched to obtain articles associated with MS and lung function published before December 31, 2021. According to the including and excluding criteria, certain studies were obtained and data were extracted. The Newcastle Ottawa Scale was used to evaluate the quality of the studies. A pooled standardized mean difference (SMD) was calculated by means of random-effects meta-analysis. Different effect models were used according to the heterogeneity. Meta-regression and sensitivity analyses were performed to examine the possible sources of heterogeneity. The Begg's funnel plot and Egger's test were used to evaluate publication bias. Analyses were performed using Stata MP, version14.0 (StataCorp LP, College Station, TX, USA). Results: A total of 15 studies, involving 10,285 cases of MS and 25,416 cases of control, were included in this meta-analysis on the relationship between MS and forced vital capacity (FVC). The pooled SMD for FVC was -0.247 (95% CI = -0.327 to -0.2167, P < 0.001) using random effect model, indicating the decrease of FVC in the patients with MS. In the same studies, the pooled SMD for forced expiratory volume in 1 sec (FEV1) was -0.205 (95% CI = -0.3278 to -0.133, P < 0.001), indicating the decrease of FEV1 also existed in the MS cases. A total of 13 studies, involving 8167 cases of MS and 19,788 cases of control, were included in this meta-analysis on the relationship between MS and FEV1/FVC. The pooled SMD for FEV1/FVC was 0.011 (95% CI = -0.072 to 0.093, P = 0.798) using random effect model, indicating that there was no significant difference between the patients with MS and the control. After introducing the diastolic blood pressure and glycemia into the regression model of the relationship between MS and FVC, the variance of the studies (tau2) decreased from 0.0190 to 0.006694 and 0.007205, which could explain 66.70% and 78.04% of the sources of heterogeneity, and the P values were 0.038 and 0.023. The results suggested that hypertension (diastolic pressure) and hyperglycemia were the factors linked to the heterogeneity among the included studies on both FVC and FEV1. The Begg's funnel plot and Egger's test both showed no evidence of publication bias. Conclusions: Our results show that FVC and FEV1 decrease in MS patients, while FEV1/FVC has no significant difference compared with the control group. It indicates that the patients with MS have restrictive ventilatory functional disturbance. Meta-regression analysis suggests that hypertension (diastolic pressure) and hyperglycemia are the factors linked to the heterogeneity among the included studies on both FVC and FEV1.

9.
Front Psychol ; 13: 901625, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36110279

RESUMO

Online social networking (OSN) has deeply penetrated university campuses, influencing multiple aspects of student life. Standing from a pedagogical perspective, this study investigates how university students' OSN engagement affect their learning outcomes. Drawn upon social learning theory, this study proposes that OSN engagement help university students' establishing the self-efficacy belief, achieving social acceptance and acculturation with environment, and these attributions further lead them to attain positive learning outcomes which are shaped by self-esteem development, satisfaction with university life, and the grade point average (GPA) based performance. Results from a survey accompanied by focus group discussions support these embedded self-conceptualization and social learning in OSN. This study contributes to the extant research on OSN for learning by highlighting the role of OSN for the whole person development, especially the students' self-conceptulization and psychological well-beings. The revealed mediating mechanisms also adds values to social learning theory and imply the design foci of e-learning activities and applications.

10.
Biomacromolecules ; 2022 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-36113205

RESUMO

The cell walls of parenchyma cells and fibers in bamboo are both highly lignified with secondary thickening. However, the former were found to have much higher nanofibrillation efficiency than fibers via both protocols of ultrasonication and high pressure homogenization. To elucidate the inherent mechanism, detailed comparisons of chemical composition, cell morphology, cell wall density, pore structures, and structural organization of cell wall polymers were performed on native and pretreated cell walls of both parenchyma cells and fibers. Chemical compositional analysis showed that fibers have much higher cellulose (49.8% to 35.5%) but lower xylan content (21.1% to 36.2%) than parenchyma, while their lignin contents were similar (24.9% vs 22.9%). Polarized FTIR further revealed clear differences in the structural organization of polymers between the two types of cells, with all the polymers of fibers being more orderly assembled than those of parenchyma cells. The compact arrangement of polymers in the fibers was also supported by the much higher cell wall density (1.52 vs 1.28 g/cm3) and lower porosity (0.007 vs 0.013 cc/g after chemical pretreatments), as compared to the parenchyma cells. The study provides evidence that the anatomical characteristics of huge cavity-wall ratio, higher cell wall porosity, and less ordered arrangement of cell wall matrix polymers (mainly lignin) in parenchyma cells contribute to their higher nanofibrillation efficiency compared to fibers.

11.
World J Clin Cases ; 10(20): 7138-7146, 2022 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-36051142

RESUMO

BACKGROUND: Aneurysm compression, diabetes, and traumatic brain injury are well-known causative factors of oculomotor nerve palsy (ONP), while cases of ONP induced by neurovascular conflicts have rarely been reported in the medical community. Here, we report a typical case of ONP caused by right posterior cerebral artery (PCA) compression to increase neurosurgeons' awareness of the disease and reduce misdiagnosis and recurrence. CASE SUMMARY: A 54-year-old man without a known medical history presented with right ONP for the past 5 years. The patient presented to the hospital with right ptosis, diplopia, anisocoria (rt 5 mm, lt 2.5 mm), loss of duction in all directions, abduction, and light impaired pupillary reflexes. Magnetic resonance angiography and computed tomography venography examinations showed no phlebangioma, aneurysm, or intracranial lesion. After conducting oral glucose tolerance and prostigmin tests, diabetes and myasthenia gravis were excluded. Cranial nerve magnetic resonance imaging showed that the right PCA loop was in direct contact with the cisternal segment of the right oculomotor nerve (ON). Microvascular decompression (MVD) of the culprit vessel from the ON through a right subtemporal craniotomy was carried out, and the ONP symptoms were significantly relieved after 3 mo. CONCLUSION: Vascular compression of the ON is a rare pathogeny of ONP that may be refractory to drug therapy and ophthalmic strabismus surgery. MVD is an effective treatment for ONP induced by neurovascular compression.

12.
Front Genet ; 13: 900864, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36072669

RESUMO

Patients with spread through air spaces (STAS) have worse postoperative survival and a higher recurrence rate in lung adenocarcinoma, even in the earliest phases of the disease. At present, the molecular pathogenesis of STAS is not well understood. Therefore, to illustrate the underlying pathogenic mechanism of STAS, we accomplished a comprehensive analysis of a microarray dataset of STAS. Differential expression analysis revealed 841 differentially expressed genes (DEGs) between STAS_positive and STAS_negative groups. Additionally, we acquired two hub genes associated with survival. Gene set variation analysis (GSVA) confirmed that the main differential signaling pathways between the two groups were hypoxia VHL targets, PKC, and pyrimidine metabolism pathways. Analysis of immune activity showed that the increased expression of MHC-class-Ⅰ was observed in the STAS_positive group. These findings provided novel insights for a better knowledge of pathogenic mechanisms and potential therapeutic markers for STAS treatment.

13.
Animals (Basel) ; 12(18)2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-36139299

RESUMO

Birds have been widely considered crucial indicators of biodiversity. It is essential to identify bird species precisely for biodiversity surveys. With the rapid development of artificial intelligence, bird species identification has been facilitated by deep learning using audio samples. Prior studies mainly focused on identifying several bird species using deep learning or machine learning based on acoustic features. In this paper, we proposed a novel deep learning method to better identify a large number of bird species based on their call. The proposed method was made of LSTM (Long Short-Term Memory) with coordinate attention. More than 70,000 bird-call audio clips, including 264 bird species, were collected from Xeno-Canto. An evaluation experiment showed that our proposed network achieved 77.43% mean average precision (mAP), which indicates that our proposed network is valuable for automatically identifying a massive number of bird species based on acoustic features and avian biodiversity monitoring.

14.
Zygote ; : 1-10, 2022 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-36148793

RESUMO

Microtubule-severing proteins (MTSPs) play important roles in mitosis and interphase. However, to the best of our knowledge, no previous studies have evaluated the role of MTSPs in female meiosis in mammals. It was found that FIGNL1, a member of MTSPs, was predominantly expressed in mouse oocytes and distributed at the spindle poles during meiosis in the present study. FIGNL1 was co-localized and interacted with γ-tubulin, an important component of the microtubule tissue centre (MTOC). Fignl1 knockdown by specific small interfering RNA caused spindle defects characterized by an abnormal length:width ratio and decreased microtubule density, which consequently led to aberrant chromosome arrangement, oocyte maturation and fertilization obstacles. In conclusion, the present results suggested that FIGNL1 may be an essential factor in oocyte maturation by influencing the meiosis process via the formation of spindles.

15.
Nanomicro Lett ; 14(1): 193, 2022 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-36149584

RESUMO

The latest view suggests the inactive core, surface pulverization, and polysulfide shuttling effect of metal sulfides are responsible for their low capacity and poor cycling performance in sodium-ion batteries (SIBs). Whereas overcoming the above problems based on conventional nanoengineering is not efficient enough. In this work, erythrocyte-like CuS microspheres with an elastic buffering layer of ultrathin polyaniline (PANI) were synthesized through one-step self-assembly growth, followed by in situ polymerization of aniline. When CuS@PANI is used as anode electrode in SIBs, it delivers high capacity, ultrahigh rate capability (500 mAh g-1 at 0.1 A g-1, and 214.5 mAh g-1 at 40 A g-1), and superior cycling life of over 7500 cycles at 20 A g-1. A series of in/ex situ characterization techniques were applied to investigate the structural evolution and sodium-ion storage mechanism. The PANI swollen with electrolyte can stabilize solid electrolyte interface layer, benefit the ion transport/charge transfer at the PANI/electrolyte interface, and restrain the size growth of Cu particles in confined space. Moreover, finite element analyses and density functional simulations confirm that the PANI film effectively buffers the volume expansion, suppresses the surface pulverization, and traps the polysulfide.

16.
Bioresour Technol ; 363: 127948, 2022 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-36108938

RESUMO

The influence of hydrazine (N2H4) and hydroxylamine (NH2OH) on performance and microbial community structures of complete autotrophic nitrogen removal over nitrite (CANON) process were assessed in this study. Experimental results demonstrated that CANON process was successfully started up and got total nitrogen removal efficiency (TNRE) of 53.6 % ± 9.8 % and 56.4 % ± 6.5 % under 1.0 and 0.5 mg L-1 N2H4 and NH2OH, respectively. N2H4 and NH2OH promoted activity of ammonia-oxidizing bacteria (AOB) and anaerobic ammonium oxidation bacteria (AnAOB), and inhibited activity of nitrite-oxidizing bacteria (NOB). Meanwhile, the stable operation of CANON process could be maintained without N2H4 auxiliary. While, performance assisted by NH2OH was fluctuated without NH2OH addition, suggesting that both N2H4 and NH2OH had a persistent and reversible inhibition on NOB. This study reveals new insights into influence of N2H4 and NH2OH on CANON performance.

17.
Int J Mol Sci ; 23(18)2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36142613

RESUMO

Radioactive iodine (RAI) plays an important role in the diagnosis and treatment of papillary thyroid cancer (PTC). The curative effects of RAI therapy are not only related to radiosensitivity but also closely related to the accumulation of radionuclides in the lesion in PTC. Sinomenine hydrochloride (SH) can suppress tumor growth and increase radiosensitivity in several tumor cells, including PTC. The aim of this research was to investigate the therapeutic potential of SH on PTC cell redifferentiation. In this study, we treated BCPAP and TPC-1 cells with SH and tested the expression of thyroid differentiation-related genes. RAI uptake caused by SH-pretreatment was also evaluated. The results indicate that 4 mM SH significantly inhibited proliferation and increased the expression of the thyroid iodine-handling gene compared with the control group (p < 0.005), including the sodium/iodide symporter (NIS). Furthermore, SH also upregulated the membrane localization of NIS and RAI uptake. We further verified that upregulation of NIS was associated with the activation of the thyroid-stimulating hormone receptor (TSHR)/cyclic adenosine monophosphate (cAMP) signaling pathway. In conclusion, SH can inhibit proliferation, induce apoptosis, promote redifferentiation, and then increase the efficacy of RAI therapy in PTC cells. Thus, our results suggest that SH could be useful as an adjuvant therapy in combination with RAI therapy in PTC.

18.
Microb Pathog ; 171: 105746, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36064103

RESUMO

OBJECTIVE: With the detection rate increasing each year, highly resistant and virulent CRKP has been a serious challenge to clinical treatment because of the high morbidity and mortality. Considering the virulence of CRKP is closely related to over-expression of siderophore, the high detection rate of entB and ybtS genes in highly virulent CRKP may be an important reason for the high virulence phenotype of CRKP. Therefore, in this study, single/double knockout and complemented strains of siderophore virulence genes entB and ybtS were constructed to clarify the effect of siderophore virulence genes on the virulence of CRKP. METHODS: 1.The wire drawing experiment, mucus phenotype screening experiment, and PCR amplification were used to screen the target strain WT. the entB gene deletion strain △entB and the complementation strain C-△entB, ybtS gene deletion strain ΔybtS and complementation strain C-ΔybtS, entB and ybtS double gene deletion strain ΔentB + ybtS and complementation strain C-ΔentB + ybtS, were constructed by CrispR-Cas9 gene editing technology. PCR method was used to test whether the knockout and complementation were successful. 2. The colony morphology and mucus phenotype of the experimental strains were observed and the siderophore ability of the experimental strains was tested. Then the growth curves, biofilm-forming ability, and anti-serum killing ability of the strains were determined. 3. In order to understand the virulence of the experimental strain, the mouse intraperitoneal infection model was established to draw the survival curves and determine LD50 of experiment strains. Then to clarify the colonization ability of the experimental strains in the lung and liver of mice, the pathological biopsies were used to observe histopathological changes and ELISA method was used to determine the inflammatory factors IL-1ß, LI-3 and TNF-α. RESULTS: 1 CRKP-27 was screened as the target strain WT, which is characterized by positive wire drawing test, strong mucus, strong virulence and carrying both entB and ybtS genes. The single/double knockout and complemented strains of siderophore virulence genes entB and ybtS were successfully constructed. 2 Siderophore virulence genes entB and ybtS had no significant effect on the colony morphology, mucus phenotype (drawing test) and biofilm formation ability of CRKP strains. The CRKP strains with entB and ybtS genes could significantly increase siderophore production. Although both the entB and ybtS genes could impair the growth rate of the CRKP strain, the role of ybtS gene was relatively slow. entB and ybtS genes enhanced the antiserum killing ability of CRKP strains. 3 The presence of entB and ybtS genes reduced the survival rate of mice infected with CRKP strains. Histopathological changes and inflammatory factor levels in the lungs and livers of infected mice were enhanced by the presence of entB and ybtS genes. Mice infected with the same strain had higher histopathological changes and levels of inflammatory factors in the lungs than in the livers. CONCLUSIONS: 1.The siderophore virulence genes entB and ybtS have no significant effect on the colony morphology, mucus phenotype and biofilm formation ability of CRKP strains.2.The siderophore virulence genes entB and ybtS can significantly enhance the virulence of the CRKP strain, but weaken its growth ability.


Assuntos
Enterobacteriáceas Resistentes a Carbapenêmicos , Infecções por Klebsiella , Animais , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Enterobacteriáceas Resistentes a Carbapenêmicos/genética , Carbapenêmicos/farmacologia , Infecções por Klebsiella/tratamento farmacológico , Klebsiella pneumoniae , Camundongos , Testes de Sensibilidade Microbiana , Sideróforos/genética , Fator de Necrose Tumoral alfa , Virulência/genética
19.
Nanomicro Lett ; 14(1): 187, 2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36104463

RESUMO

Lithium metal anode has been demonstrated as the most promising anode for lithium batteries because of its high theoretical capacity, but infinite volume change and dendritic growth during Li electrodeposition have prevented its practical applications. Both physical morphology confinement and chemical adsorption/diffusion regulation are two crucial approaches to designing lithiophilic materials to alleviate dendrite of Li metal anode. However, their roles in suppressing dendrite growth for long-life Li anode are not fully understood yet. Herein, three different Ni-based nanosheet arrays (NiO-NS, Ni3N-NS, and Ni5P4-NS) on carbon cloth as proof-of-concept lithiophilic frameworks are proposed for Li metal anodes. The two-dimensional nanoarray is more promising to facilitate uniform Li+ flow and electric field. Compared with the NiO-NS and the Ni5P4-NS, the Ni3N-NS on carbon cloth after reacting with molten Li (Li-Ni/Li3N-NS@CC) can afford the strongest adsorption to Li+ and the most rapid Li+ diffusion path. Therefore, the Li-Ni/Li3N-NS@CC electrode realizes the lowest overpotential and the most excellent electrochemical performance (60 mA cm-2 and 60 mAh cm-2 for 1000 h). Furthermore, a remarkable full battery (LiFePO4||Li-Ni/Li3N-NS@CC) reaches 300 cycles at 2C. This research provides valuable insight into designing dendrite-free alkali metal batteries.

20.
Anal Chim Acta ; 1227: 340303, 2022 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-36089315

RESUMO

Accurate analysis of HIV DNA is valuable for the diagnosis of AIDS. Herein, an ultrasensitive and specific fluorescence method was developed for HIV-1 DNA detection based on CRISPR-Cas12a-activated palindrome-catalytic hairpin assembly (CRISPR-Cas12a-PCHA). The presence of HIV-1 DNA activated the trans-cleavage activity of CRISPR-Cas12a, which could continuously digest the DNA fragment of hairpins connected to magnetic beads to expose single-stranded RNA. After magnetic separation, the exposed RNA triggered multiple PCHA reactions, generating many Y-shaped DNA structures that were self-assembled into the DNA superstructures via the hybridization of palindromic sticky ends, leading to the release of amounts of fluorescence signal. Different from the reported recently biosensing strategies of nucleic acid amplification technologies-activated CRISPR-Cas12a, CRISPR-Cas12a-PCHA endowed the strategy with unique advantages of simple sample pretreatment, direct duplex target detection, and ultrahigh sensitivity. The strategy was able to resist the interference of the complex matrix in real sample and distinguish between HIV patients and healthy persons. Thus, the method is a promising tool for ultrasensitive and specific detection of HIV-1 DNA for AIDS diagnosis.


Assuntos
Síndrome de Imunodeficiência Adquirida , Infecções por HIV , HIV-1 , Síndrome de Imunodeficiência Adquirida/genética , Sistemas CRISPR-Cas , DNA/química , Infecções por HIV/diagnóstico , HIV-1/genética , Humanos , RNA
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