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1.
Clin Microbiol Infect ; 30(4): 507-514, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38295990

RESUMO

OBJECTIVES: To study the clinical relevance, mechanisms, and evolution of polymyxin B (POLB) heteroresistance (PHR) in carbapenem-resistant Klebsiella pneumoniae (CRKP), potentially leading to a significant rise in POLB full resistant (FR) CRKP. METHODS: Total of 544 CRKP isolates from 154 patients treated with POLB were categorized into PHR and POLB non-heteroresistance (NHR) groups. We performed statistical analysis to compare clinical implications and treatment responses. We employed whole-genome sequencing, bioinformatics, and PCR to study the molecular epidemiology, mechanisms behind PHR, and its evolution into FR. RESULTS: We observed a considerable proportion (118 of 154, 76.62%) of clinically undetected PHR strains before POLB exposure, with a significant subset of them (33 of 118, 27.97%) evolving into FR after POLB treatment. We investigated the clinical implications, epidemiological characteristics, mechanisms, and evolutionary patterns of PHR strains in the context of POLB treatment. About 92.86% (39 of 42) of patients had PHR isolates before FR, highlighting the clinical importance of PHR. the ST15 exhibited a notably lower PHR rate (1 of 8, 12.5% vs. 117 of 144, 81.25%; p < 0.01). The ST11 PHR strains showing significantly higher rate of mgrB mutations by endogenous insertion sequences in their resistant subpopulation (RS) compared with other STs (78 of 106, 73.58% vs. 4 of 12, 33.33%; p < 0.01). The mgrB insertional inactivation rate was lower in FR isolates than in the RS of PHR isolates (15 of 42, 35.71% vs. 84 of 112, 75%; p < 0.01), whereas the pmrAB mutation rate was higher in FR isolates than in the RS of PHR isolates (8 of 42, 19.05% vs. 2 of 112, 1.79%; p < 0.01). The evolution from PHR to FR was influenced by subpopulation dynamics and genetic adaptability because of hypermutability. DISCUSSION: We highlight significant genetic changes as the primary driver of PHR to FR in CRKP, underscoring polymyxin complexity.


Assuntos
Enterobacteriáceas Resistentes a Carbapenêmicos , Infecções por Klebsiella , Humanos , Polimixinas , Polimixina B/farmacologia , Relevância Clínica , Klebsiella pneumoniae/genética , Estudos Retrospectivos , Genômica , Enterobacteriáceas Resistentes a Carbapenêmicos/genética , Carbapenêmicos/farmacologia , Infecções por Klebsiella/tratamento farmacológico , Infecções por Klebsiella/epidemiologia , Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana
2.
Sci Total Environ ; 896: 165203, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37406695

RESUMO

The rapid global dissemination of Salmonella enterica sequence type 34 (ST34) has sparked significant concern due to its resistance to critical antimicrobials and its ability to spread across various sectors. In order to investigate the evolution and transmission dynamics of this epidemic clonal lineage, as well as the horizontal transfer of mcr-carrying plasmids within the One Health framework, we conducted a comprehensive genomic epidemiological study. This study focused on the 11 mcr-carrying S. enterica isolates obtained from clinical settings in China, while also considering 2337 publicly available genomes of mcr-carrying S. enterica collected from 20 countries and diverse sources spanning over a 22-year period. Among the mcr-positive Salmonella isolates, ST34 was found to be the predominant lineage, comprising 30.12 % (704/2337) of the total collection. These isolates were identified as either serovar Typhimurium or its monophasic variant, which were obtained from both clinical and non-clinical sources. Phylogeographic analyses traced the global spread of the mcr-carrying ST34 lineage, which was divided into three distinct clusters, with 83.10 % of them carrying mcr-1 or/and mcr-9 genes. Notably, the mcr-1 positive ST34 isolates were primarily found in China (190/298, 63.76 %), with only four from the United States. Conversely, mcr-9 positive ST34 isolates were predominantly identified in the United States (261/293, 89.08 %), while none were observed in China. The mcr-1 positive ST34 isolates was predicted to have originated from clinical sources in United Kingdom, whereas mcr-9 positive ST34 isolates was likely derived from environmental sources in Germany. The most recent common ancestor for mcr-1 and mcr-9 carrying ST34 S. enterica was estimated to have emerged around 1983 and 1951. These findings provided thorough and intuitive insights into the intercontinental spread of mcr-carrying S. enterica ST34 lineage in a One Health context. Ongoing surveillance is crucial for effectively monitoring the worldwide dissemination of this multidrug-resistant high-risk clone.


Assuntos
Saúde Única , Salmonella enterica , Salmonella typhimurium/genética , Sorogrupo , Salmonella enterica/genética , Plasmídeos , Genômica , Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana
3.
Genes (Basel) ; 13(12)2022 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-36553664

RESUMO

The Tibetan pig is an endemic economic animal in the plateau region of China, and has a unique adaptation mechanism to the plateau hypoxic environment. Research into microRNAs (miRNAs) involved in the mechanism underlying hypoxia adaptation of Tibetan pig is very limited. Therefore, we isolated alveolar type II epithelial (ATII) cells from the lungs of the Tibetan pig, cultured them in normoxia/hypoxia (21% O2; 2% O2) for 48 h, and performed high-throughput sequencing analysis. We identified a hypoxic stress-related ssc-miR-141 and predicted its target genes. The target genes of ssc-miR-141 were mainly enriched in mitogen-activated protein kinase (MAPK), autophagy-animal, and Ras signaling pathways. Further, we confirmed that PDCD4 may serve as the target gene of ssc-miR-141. Real-time quantitative polymerase chain reaction (RT-qPCR) analysis was performed to confirm the expression levels of ssc-miR-141 and PDCD4, and a dual-luciferase gene reporter system was used to verify the targeted linkage of ssc-miR-141 to PDCD4. The results showed that the expression level of ssc-miR-141 in the hypoxia group was higher than that in the normoxia group, while the expression level of PDCD4 tended to show the opposite trend and significantly decreased under hypoxia. These findings suggest that ssc-miR-141 is associated with hypoxia adaptation and provide a new insight into the role of miRNAs from ATII cells of Tibetan pig in hypoxia adaptation.


Assuntos
MicroRNAs , Suínos/genética , Animais , Tibet , MicroRNAs/genética , MicroRNAs/metabolismo , Proteínas Reguladoras de Apoptose/genética , Hipóxia/genética , Células Epiteliais/metabolismo
4.
Front Microbiol ; 13: 1030564, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36386612

RESUMO

The aquatic environment is an important medium for the accumulation and dissemination of antibiotic-resistant bacteria as it is often closely related to human activities. Previous studies paid little attention to the prevalence and mechanism of polymyxin-resistant bacteria in the aquatic environment. As a Gram-negative opportunistic pathogen widely distributed in aquatic ecosystems, the antibiotic-resistant profile of Aeromonas spp. deserves much attention. In this study, we identified 61 Aeromonas spp. isolates from water samples in the section of the Yangtze River. The total polymyxin B (PMB) resistance rate of these strains was 49.18% (30/61), showing a high level of polymyxin resistance in Aeromonas spp. The MIC50 and MIC90 for PMB exhibited a significant discrepancy among different species (p < 0.001). The MIC50 and MIC90 for PMB in the Aeromonas hydrophila were 128 mg/L and above 128 mg/L while in Aeromonas caviae and Aeromonas veronii, the MIC50 and MIC90 value were both 2 mg/L. Only two A. veronii strains (MIC = 2 mg/L) and one A. caviae strain (MIC = 0.5 mg/L) were identified as carrying mobilized polymyxin resistant gene mcr-3.42, and mcr-3.16. All mcr genes were located in the chromosome. This is the first report that the downstream region of mcr-3.42 was the truncated mcr-3-like gene separated by the insertion sequences of ISAs20 (1,674 bp) and ISAs2 (1,084 bp). Analysis of epidemiology of mcr-positive Aeromonas genomes from GenBank database showed that the genus Aeromonas and the aquatic environment might be the potential container and reservoir of mcr-3. By the whole-genome sequencing and qRT-PCR, we inferred that the sequence differences in the AAA domain of MlaF protein and its expression level among these three species might be involved in the development of polymyxin resistance. Our study provided evidences of the possible mechanism for the variety of polymyxin susceptibility in different species of the genus Aeromonas and a theoretical basis for the surveillance of the aquatic environment.

5.
Ecotoxicol Environ Saf ; 241: 113723, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35679725

RESUMO

Constitutional delay of growth and puberty (CDGP) refers to the late onset of puberty. CDGP is associated with poor psychosocial outcomes and elevated risk of cardiovascular and osteoporotic diseases, especially in women. The environmental factors that contribute to CDGP are poorly understood. Here, we investigated the effects of chronic circadian disturbance (CCD) during the fetal stage on the pubertal development of female mice. Compared to non-stressed female (NS-F) mice that were not exposed to CCD in utero, adolescent CCD female (CCD-F) mice exhibited phenotypes that were consistent with CDGP, including lower body weight, reduced levels of circulating gonadal hormones, decreased expression of gonadal hormones and steroid synthesis-related enzymes in the ovary and hypothalamus, irregular estrus cycles, and tardive vaginal introitus initial opening (VO) days (equivalent to the menarche). Phenotypic differences in the above-noted parameters were not observed in CCD-F mice once they had reached adulthood. The expression of genes involved in fatty acid metabolism was perturbed in the ovary and hypothalamus of CCD-F mice. In addition, the ovaries of these animals exhibited altered diurnal expression profiles of circadian clock genes. Together, our findings not only suggest that CCD during fetal development may result in delayed puberty in female mice, they also offer insights on potential mechanisms that underlie CDGP.


Assuntos
Puberdade Tardia , Animais , Ritmo Circadiano , Feminino , Humanos , Camundongos , Puberdade
6.
RSC Adv ; 12(11): 6881-6887, 2022 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-35424593

RESUMO

Polyphenols have found a lot of therapeutic effects and potential applications such as antioxidant, anti-inflammatory, mutant resistance, immunosuppressant and anti-tumor properties. They can be divided into five main classes, namely flavonoids, phenolic acids, stilbenes, lignans, and others. Thus, the content detection of polyphenols in real samples such as fruit juice and tea is of great significance. Due to the presence of complex interfering components in actual samples, separation and enrichment of polyphenols prior to analysis is key. Therefore, it is quite necessary to establish a simple, low-cost and efficient purification method for cis-diol-containing polyphenols from real samples. Boronate affinity materials are able to reversibly bind cis-diol-containing compounds by forming a five- or six-membered boronic cyclic ester in aqueous media. However, conventional boronate affinity materials exhibited low binding capacity and high binding pH. In this study, the polyethyleneimine (PEI)-assisted 6-aminopyridine-3-boronic acid functionalized magnetic nanoparticles (MNPs) were developed to capture efficiently cis-diol-containing polyphenols under neutral condition. PEI was applied as a scaffold to amplify the number of boronic acid moieties. While 6-aminopyridine-3-boronic acid was used as an affinity ligand due to low pK a value and excellent water solubility toward polyphenols. The results indicated that the prepared boronic acid-functionalized MNPs provided high binding capacity and fast binding kinetics under neutral conditions. In addition, the obtained MNPs exhibited relatively high binding affinity (K d ≈ 10-4 M), low binding pH (pH ≥ 6.0) and tolerance of the interference of abundant sugars.

7.
Microbiol Spectr ; 10(2): e0041822, 2022 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-35412362

RESUMO

The wide spread of plasmid-borne mobilized colistin resistance (mcr) genes from animals to humans broadly challenges the clinical use of polymyxins. Here, we evaluated the incidence of a recently reported mcr variant, mcr-10, in animals and humans in the same area. Our results revealed the presence of novel mcr-10-carrying plasmids in two Klebsiella pneumoniae isolates from chickens, one Escherichia coli isolate from slaughterhouse workers, and a chromosome-borne mcr-10 gene in Enterobacter kobei from a healthy resident in the same region. It is worth mentioning that the multidrug-resistant ST11 K. pneumoniae isolates coharboring mcr-10 and mcr-8 genes in two separate plasmids not only were resistant to polymyxins (MIC = 8 mg/L) but also showed reduced susceptibility to tigecycline (MIC ≥ 2 mg/L) due to the tet(A) mutation or the tmexCD1-toprJ1 gene cluster. The structure xerC-mcr10-insCinsD-like was found in genetic environments of both the plasmid and chromosome carrying mcr-10. We compared genomic epidemiological characteristics of mcr-10-harboring bacteria available in 941,449 genomes in the NCBI database (including strains of K. pneumoniae, E. coli, and E. kobei) with isolates in this study. The results indicated a sporadic distribution of mcr-10 all around the world and in a variety of sources, including humans, environments, and animals, which confirms that mcr-10 has spread among various hosts and warrants close monitoring and further future studies. IMPORTANCE We discovered mcr-10-harboring isolates in the "one health" approach and reported for the first time multidrug-resistant clinically threatening ST11 K. pneumoniae isolates coharboring mcr-10 and mcr-8 genes that are resistant to polymyxins and show reduced susceptibility to tigecycline. The exhaustive screening of 941,449 bacterial genomes in the GenBank database discovered a sporadic distribution of mcr-10-harboring isolates all around the world in a variety of sources, especially humans, which warrants close monitoring and a particular concern in clinical settings.


Assuntos
Colistina , Proteínas de Escherichia coli , Matadouros , Animais , Antibacterianos/farmacologia , Galinhas , Colistina/farmacologia , Farmacorresistência Bacteriana/genética , Escherichia coli , Proteínas de Escherichia coli/genética , Integrases/genética , Klebsiella pneumoniae/genética , Testes de Sensibilidade Microbiana , Plasmídeos/genética , Tigeciclina
8.
Phytochemistry ; 194: 113021, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34826795

RESUMO

Salvia miltiorrhiza is a traditional medicinal plant mainly used for cardiovascular and cerebrovascular disease treatment. Tanshinones are the main bioactive constituents of S. miltiorrhiza, which mainly accumulate around its root periderm tissue. Endophytic fungi are important bioelicitors or probiotics that can promote the accumulation of secondary metabolites and sustainable cultivation of medicinal plants. Among them, endophytic Cladosporium spp., possessing a variety of biotransformation and metabolic abilities, is an ideal elicitor source. Here, we used a gnotobiotic system to investigate the effects of the endophytic fungus Cladosporium tenuissimum DF11 on tanshinone biosynthesis in S. miltiorrhiza roots. The results showed that C. tenuissimum DF11 mainly colonizes the intercellular space of the root tissues and promotes tanshinone biosynthesis and accumulation in S. miltiorrhiza roots by upregulating the expression of the genes encoding for key enzymes HMGR, DXS, DXR, GGPPS, CPS, KSL and CYP76AH1 of the tanshinone biosynthesis pathway. The expression levels of almost all genes encoding for key enzymes reached the response peak in the first or second week after DF11 colonization. Taken together, the endophytic fungus C. tenuissimum DF11 could promote secondary metabolite accumulation in S. miltiorrhiza roots. These results indicate that DF11 will be a potential biofertilizer fungus to regulate and stabilize the quality of cultivated S. miltiorrhiza medicinal materials.


Assuntos
Cladosporium , Salvia miltiorrhiza , Abietanos
10.
Infect Drug Resist ; 14: 2437-2447, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34234474

RESUMO

PURPOSE: Colistin is one of the last-resort antimicrobial agents that combat the increasing threat of multi-drug resistant (MDR) gram-negative bacteria. Based on the known mechanism of colistin resistance which contributes to chromosomal mutations involved in the synthesis and modification of lipopolysaccharide (LPS), we explored the regulatory genes mediate colistin resistance, by whole genome sequencing and transcriptome analysis. MATERIALS AND METHODS: In this study, a colistin-resistant (Colr) strain Escherichia coli ATCC 25922-R was generated from colistin-sensible (Cols) strain E. coli ATCC 25922 by colistin induction. We compared the genome and transcriptome sequencing result from Cols and Colr strain. MALDI-TOF mass spectrometry was used to detect LPS. RESULTS: Genomic analysis and complementation experiment demonstrated the PmrB amino acid substitution in ATCC 25922-R (L14R) conferred the colistin resistance phenotype. Results of RNA sequencing (RNA-Seq) and comparative transcriptome analysis indicated that the two-component system EvgS/EvgA is highly involved in the global regulation of colistin resistance. CONCLUSION: This study demonstrated that PmrB L14R amino acid substitution resulted in colistin resistance, and two-component system EvgS/EvgA might participate in colistin resistance in E. coli.

11.
Plant Sci ; 307: 110898, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33902857

RESUMO

As a traditional Chinese medicine, Salvia miltiorrhiza rhizome is mainly used to treat cardiovascular diseases. Symbiosis of endophytic fungi with their host plants, is an effectively regulatory means to promote the growth and secondary metabolism of medicinal plants. Here, an endophytic fungus Mucor circinelloides DF20 was co-cultivated with the sterile seedlings of S. miltiorrhiza, to clarify the promoting mechanism on tanshinone biosynthesis and accumulation in S. miltiorrhiza root. The assay of promoting-growth activities in vitro showed that DF20 have the ability to produce IAA and siderophores. DF20 could significantly promote the biosynthesis and accumulation of tanshinones in the root of S. miltiorrhiza, especially the content of tanshinone ⅡA, reaching 4.630 ± 0.342 mg/g after 56 days of DF20 treatment, which is 22-fold of the control group. The result also showed that the hyphae of M. circunelloides DF20 mainly colonized in the root tissue interspace of S. miltiorrhiza, and a small amount of hyphae were located inside the cells. The results of florescent real-time quantitative RT-PCR showed that DF20 colonization significantly increase the expression level of some key enzyme genes (DXS, DXR, HMGR, GGPPS) in tanshinone biosynthesis pathway, but the regulatory effect mainly occurred in the early stage of co-culture, while the expression level decreased in different degrees in the later stage. In conclusion, the endophytic fungus M. circunelloides DF20 can form an interaction relationship with its host, then to promote the biosynthesis and accumulation of tanshinones in root by upregulating the key enzyme genes expression levels of the biosynthesis pathway.


Assuntos
Abietanos/biossíntese , Endófitos/metabolismo , Mucor/metabolismo , Raízes de Plantas/metabolismo , Salvia miltiorrhiza/crescimento & desenvolvimento , Salvia miltiorrhiza/metabolismo , Salvia miltiorrhiza/microbiologia , Plantas Medicinais/crescimento & desenvolvimento , Plantas Medicinais/metabolismo
12.
J Stud Alcohol Drugs ; 82(1): 66-75, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33573724

RESUMO

OBJECTIVE: This study investigated the effect of keg registration laws on alcohol consumption and alcohol-related traffic fatalities in the United States. METHOD: The 1993-2013 data from Youth Risk Behavior Surveillance System (n = 107,480) and Fatality Analysis Reporting System (n = 12,102) and difference-in-differences type models were used to estimate the effect of keg registration laws on different indicators of alcohol consumption and alcohol-related traffic fatalities among underage youth. RESULTS: Introduction of keg registration laws was associated with a 2.3 percentage point reduction (p < .01) in heavy episodic drinking among minors. The significant effects of these laws were mainly driven by the states with relatively strict keg registration laws. However, these laws did not have a significant impact on alcohol-related traffic fatalities among underage youth. These results were robust under alternative model specifications. CONCLUSIONS: We found that keg registration laws are effective in reducing heavy episodic drinking among underage youth. This result is important given that an increasing number of states have adopted keg registration laws in recent years, yet the empirical evidence of the effectiveness of this policy is quite limited.


Assuntos
Acidentes de Trânsito/estatística & dados numéricos , Consumo de Bebidas Alcoólicas/epidemiologia , Condução de Veículo/estatística & dados numéricos , Acidentes de Trânsito/legislação & jurisprudência , Adolescente , Comportamento do Adolescente , Condução de Veículo/legislação & jurisprudência , Feminino , Humanos , Masculino , Assunção de Riscos , Estados Unidos
13.
J Cardiovasc Electrophysiol ; 32(5): 1346-1354, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33010088

RESUMO

INTRODUCTION: Cardiac implantable electronic device (CIED) pocket related problems such as infection, hematoma, and device erosion cause significant morbidity and the clinical consequences are substantial. Bioabsorbable materials have been developed to assist in the prevention of these complications but there has not been any direct comparison of these adjunctive devices to reduce these complications. We sought to directly compare the TYRX absorbable antibacterial and CanGaroo extracellular matrix (ECM) envelopes in an animal model susceptible to these specific CIED-related complications (i.e., skin erosion and infection). METHODS AND RESULTS: Sixteen mice undergoing implantation with biopotential transmitters were divided into three groups (no envelope = 4, TYRX = 5, and CanGaroo = 7) and monitored for device-related complications. Following 12 weeks of implantation, gross and histological analysis of the remaining capsules was performed. Three animals in the CanGaroo group (43%) had device erosion compared to none in the TYRX group. The remaining capsules excised at 12 weeks were qualitatively thicker following CanGaroo compared to TYRX and no envelope and histological evaluation demonstrated increased connective tissue with CanGaroo. CONCLUSION: CanGaroo ECM envelopes did not reduce the incidence of device erosion and were associated with qualitatively thicker capsules and connective tissue staining at 12 weeks compared to no envelope or TYRX. Further studies regarding the use of these envelopes to prevent device erosion and their subsequent impact on capsule formation are warranted.


Assuntos
Desfibriladores Implantáveis , Infecções Relacionadas à Prótese , Animais , Antibacterianos , Desfibriladores Implantáveis/efeitos adversos , Eletrônica , Camundongos , Modelos Animais , Infecções Relacionadas à Prótese/etiologia , Infecções Relacionadas à Prótese/prevenção & controle
14.
Int J Nanomedicine ; 15: 7397-7413, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33116478

RESUMO

BACKGROUND: The toxicity of silica nanoparticles (SiNPs) on cardiac electrophysiology has seldom been evaluated. METHODS: Patch-clamp was used to investigate the acute effects of SiNP-100 (100 nm) and SiNP-20 (20 nm) on the transmembrane potentials (TMPs) and ion channels in cultured neonatal mouse ventricular myocytes. Calcium mobilization in vitro, cardiomyocyte ROS generation, and LDH leakage after exposure to SiNPs in vitro and in vivo were measured using a microplate reader. Surface electrocardiograms were recorded in adult mice to evaluate the arrhythmogenic effects of SiNPs in vivo. SiNP endocytosis was observed using transmission electron microscopy. RESULTS: Within 30 min, both SiNPs (10-8-10-6 g/mL) did not affect the resting potential and IK1 channels. SiNP-100 increased the action potential amplitude (APA) and the INa current density, but SiNP-20 decreased APA and INa density. SiNP-100 prolonged the action potential duration (APD) and decreased the Ito current density, while SiNP-20 prolonged or shortened the APD, depending on exposure concentrations and increased Ito density. Both SiNPs (10-6 g/mL) induced calcium mobilization but did not increase ROS and LDH levels and were not endocytosed within 10 min in cardiomyocytes in vitro. In vivo, SiNP-100 (4-10 mg/kg) and SiNP-20 (4-30 mg/kg) did not elevate myocardial ROS but increased LDH levels depending on dose and exposure time. The same higher dose of SiNPs (intravenously injected) induced tachyarrhythmias and lethal bradyarrhythmias within 90 min in adult mice. CONCLUSION: SiNPs (i) exert rapid toxic effects on the TMPs of cardiomyocytes in vitro largely owing to their direct interfering effects on the INa and Ito channels and Ca2+ homeostasis but not IK1 channels and ROS levels, and (ii) induce tachyarrhythmias and lethal bradyarrhythmias in vivo. SiNP-100 is more toxic than SiNP-20 on cardiac electrophysiology, and the toxicity mechanism is likely more complicated in vivo.


Assuntos
Arritmias Cardíacas/induzido quimicamente , Canais Iônicos/metabolismo , Potenciais da Membrana/efeitos dos fármacos , Miócitos Cardíacos/efeitos dos fármacos , Nanopartículas/toxicidade , Dióxido de Silício/toxicidade , Potenciais de Ação/efeitos dos fármacos , Animais , Arritmias Cardíacas/metabolismo , Arritmias Cardíacas/mortalidade , Células Cultivadas , Eletrocardiografia , Endocitose/efeitos dos fármacos , L-Lactato Desidrogenase/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Microscopia Eletrônica de Transmissão , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Nanopartículas/química , Técnicas de Patch-Clamp , Espécies Reativas de Oxigênio/metabolismo
15.
ACS Appl Mater Interfaces ; 12(16): 18934-18943, 2020 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-32233390

RESUMO

It is well known that the upconversion luminescence from lanthanide metal-organic frameworks (Ln-MOFs) is difficult to achieve, and thus, there are few reports on dual luminescence-based MOFs. Here, dual-mode light-emitting Ln-MOFs are synthesized using a low-cost hydrothermal method. Our results show that the obtained Ln-MOFs not only have high thermal stability (up to 420°) but also are stable in deionized water. The dual-mode up- and downconversion luminescence is simultaneously observed from Er-Eu-MOFs. The temperature-dependent fluorescence decay time is calculated to be ranging from 0.46 to 0.36 ms for temperatures from 100 to 300 K. We suggested that this phenomenon was because the number of phonons participating in the MOF matrix increases with temperature during the luminescence process, and the phonons interact with the electrons in the material. The values of the J-O parameters calculated from the emission spectra indicated that the symmetry around Eu3+ ions in Eu-MOF is the highest, which was also higher than that of Er-Eu-MOF. To explore the potential applications of Eu-MOFs in white light-emitting diodes (LEDs), red emission from Eu-MOFs was combined with blue, green, and yellow emissions from metal halide perovskites to achieve white light emission. White light with excellent color quality and vision performance was obtained. These findings demonstrate that Ln-MOFs are potentially successful materials for applications in white LEDs.

16.
Nanomaterials (Basel) ; 9(9)2019 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-31500216

RESUMO

Multifunctional nanomaterials for bioprobe and drug carrier have drawn great attention for their applications in the early monitoring the progression and treatment of cancers. In this work, we have developed new multifunctional water-soluble NaLnF4@MOF-Ln nanocomposites with dual-mode luminescence, which is based on stokes luminescent mesoporous lanthanide metal-organic frameworks (MOFs-Y:Eu3+) and anti-stokes luminescent NaYF4:Tm3+/Yb3+ nanoparticles. The fluorescence mechanism and dynamics are investigated and the applications of these nanocomposites as bioprobes and drug carriers in the cancer imaging and treatment are explored. Our results demonstrate that these nanocomposites with the excellent two-color emission show great potential in drug delivery, cancer cell imaging, and treatment, which are attributed to the unique spatial structure and good biocompatibility characteristics of NaLnF4@MOF-Ln nanocomposites.

17.
Gene ; 689: 90-96, 2019 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-30572095

RESUMO

Copy number variation is a large genome variation which usually happens in the noncoding-region, and it may occur at the locus associated with the functional gene to further influence the phenotype. Potassium inwardly-rectifying channel, subfamily J 12 (KCNJ12) gene expressed widely in cardiomyocytes and neurons, plays an important role in tumor therapy and muscle movement regulation. In this study, we detected the distribution of CNVs for KCNJ12 gene in 404 individuals belonging to four Chinese cattle breeds (NY, JX, JA and GF). We also investigated the KCNJ12 gene expression in different tissues of JX cattle. Additionally, we examined the association of two CNV regions (CNV1: 1,600 bp, intron 1; CNV2: 4,800 bp, intergenic) with growth traits. The statistical analyses indicated that the CNV1 is associated with the body length, rump length and weight in JX cattle population (P < 0.05); and there has a significant association with the body length, chest circumference, and body weight in GF cattle (P < 0.05).The CNV2 had a significant effect on the body length and body weight in JX cattle (P < 0.05); the body length, chest circumference, rump length and body weight in GF cattle (P < 0.01 or P < 0.05). The copy numbers of KCNJ12 gene presented the negative correlations with the transcript level of gene in skeletal muscles (P < 0.05). Our results provide evidence that CNV1 and CNV 2 in KCNJ12 are associated with growth traits in two cattle populations and may be used as candidates for marker-assisted selection and breeding management in cattle.


Assuntos
Tamanho Corporal/genética , Peso Corporal/genética , Bovinos/crescimento & desenvolvimento , Bovinos/genética , Canais de Potássio Corretores do Fluxo de Internalização/genética , Animais , Cruzamento , China/epidemiologia , Variações do Número de Cópias de DNA , Feminino , Estudos de Associação Genética/veterinária , Desequilíbrio de Ligação , Fenótipo , Característica Quantitativa Herdável
18.
Clin Proteomics ; 15: 36, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30479583

RESUMO

BACKGROUND: Natural menopause is always accompanied by specific signs and symptoms, suggesting physiological changes in this peoriod. However, no systematic study has assessed the changes at molecular level in the ovaries during the menopausal transition so far. This study integrated quantitative proteome and acetyl-proteome to comprehensively uncover the changes of ovarian protein and protein-acetylation profiles in this transitional period. The findings would provide novel insights into the biology of menopause and help relieve and treat the associated signs and symptoms, further improving the women's health care. METHODS: Freshly thawed ovarian tissue samples obtained from premenopausal and postmenopausal women were assessed with Tandem Mass Tags for the quantitative analysis of the global profile and acetyl-proteomes by 2-dimensional separation and LC-MS/MS. RESULTS: Comprehensively, 4210 types of protein, with 3551 types quantifiable were detected. 3047 acetylated sites in 1583 types of protein with 2256 quantifiable in 1248 proteins were detected. By comparing the global and acetylated proteome profiles for postmenopausal women and premenopausal women, 151 types of proteins were found upregulated and 65 were downregulated, along with 23 acetylated sites upregulated and 220 sites downregulated. For Immune response, the complement and coagulation cascades plus the citrate cycle and cellular detoxification were found to be significantly enhanced, while the extracellular structure and matrix organization, ECM-receptor interactions plus the infections were markedly suppressed. In addition, the amino acids around the acetylated sites were enriched by motif analysis, which can help us uncover amino acid sequence and search for the specific target in the subsequent study. CONCLUSION: Global and acetylated proteome Profiles in ovary differ between the premenopausal and postmenopausal groups. These proteomic-level changes may offer some potential biological markers to identify the pathological changes in ovary and help relieve and treat the associated signs and symptoms, and ultimately improve women's health care.

19.
BMC Psychiatry ; 17(1): 287, 2017 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-28768497

RESUMO

BACKGROUND: Prison is an extremely stressful environment and prisoners have an increasing risk of suffering from alexithymia. Therefore, this study aims to investigate the prevalence and associated factors of alexithymia among prisoners in China. METHODS: A cross-sectional study was conducted in five main jails of the district of Zhejiang province in China, and a total of 1705 adult prisoners ultimately took part in the study. Toronto Alexithymia Scale, Childhood Trauma Questionnaire, Beck Depression Inventory, Beck Anxiety Inventory, Beck Hopelessness Scale and several short demographic questions were applied. RESULTS: Over 30% of prisoners were classified as alexithymics and as high as 96.2% of prisoners suffered from at least one traumatic experience in their childhood, meanwhile, 81.5%, 53.4% and 85.8% were found to be positive for depression, anxiety and hopelessness symptoms respectively. Education, childhood trauma, negative emotional symptoms including depression, anxiety and hopelessness of the respondents, were negatively or positively associated with alexithymia among prisoners. CONCLUSIONS: The results indicated that high prevalence of alexithymia among prisoners is linked with their level of education, experience of childhood trauma and symptoms of negative emotions. Accordingly, the findings in our study can be used for prevention and intervention of alexithymia among prisoners.


Assuntos
Adultos Sobreviventes de Eventos Adversos na Infância/estatística & dados numéricos , Sintomas Afetivos/epidemiologia , Sintomas Afetivos/psicologia , Ansiedade/epidemiologia , Depressão/epidemiologia , Emoções , Prisioneiros/psicologia , Prisioneiros/estatística & dados numéricos , Adulto , Adultos Sobreviventes de Eventos Adversos na Infância/psicologia , Ansiedade/psicologia , China/epidemiologia , Comorbidade , Estudos Transversais , Depressão/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência
20.
Int J Cardiol ; 180: 228-36, 2015 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-25463374

RESUMO

BACKGROUND: Ryanodine receptor (RyR2) mutations have largely been associated with catecholaminergic polymorphic ventricular tachycardia (PMVT). The role of RyR2 mutations in the pathogenesis of arrhythmias and syncope at rest is unknown. We sought to characterize the clinical and functional characteristics associated with a novel RyR2 mutation found in a mother and daughter with PMVT at rest. METHODS AND RESULTS: A 31-year-old female with syncope at rest and recurrent short-coupled premature ventricular contractions (PVCs) initiating PMVT was found to be heterozygous for a novel RyR2-H29D mutation. Her mother, who also had syncope at rest and short-coupled PMVT, was found to harbor the same mutation. Human RyR2-H29D mutant channels were generated using site-directed mutagenesis and heterologously expressed in HEK293 cells together with the stabilizing protein calstabin2 (FKPB12.6). Single channel measurements of RyR2-H29D mutant channels and wild type (WT) RyR2 channels were compared at varying concentrations of cytosolic Ca(2+). Binding affinities of the RyR2-H29D channels and RyR2-WT channels to calstabin2 were compared. Functional characterization of the RyR2-H29D mutant channel revealed significantly higher open probability and opening frequency at diastolic levels of cytosolic Ca(2+) under non-stress conditions without protein kinase A treatment. This was associated with a modest depletion of calstabin2 binding under resting conditions. CONCLUSIONS: The RyR2-H29D mutation is associated with a clinical phenotype of short-coupled PMVT at rest. In contrast to catecholaminergic PMVT-associated RyR2 mutations, RyR2-H29D causes a leaky channel at diastolic levels of Ca(2+) under non-stress conditions. Leaky RyR2 may be an under-recognized mechanism for idiopathic PMVT at rest.


Assuntos
DNA/genética , Mutação , Descanso/fisiologia , Canal de Liberação de Cálcio do Receptor de Rianodina/genética , Taquicardia Ventricular/genética , Adulto , Análise Mutacional de DNA , Feminino , Heterozigoto , Humanos , Linhagem , Fenótipo , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo , Taquicardia Ventricular/metabolismo , Taquicardia Ventricular/fisiopatologia
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