Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 49
Filtrar
1.
Drug Resist Updat ; 72: 101029, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38071861

RESUMO

Mycoplasma hominis, a commensal bacterium that commonly inhabits the genital tract, leading to infections in both the genitourinary and extragenital regions. However, the antimicrobial resistance and pathogenic mechanisms of M. hominis isolated from extra-urogenital cystic abscess is largely unknown. This study reports the genomic epidemiological characteristics of a M. hominis isolate recovered from a pelvic abscess sample in China. Genomic DNA was extracted and sequenced using Illumina HiSeq X Ten platform. De novo assembly was performed and in silico analysis was accomplished by multiple bioinformatics tools. For phylogenomic analysis, publicly available M. hominis genomes were retrieved from NCBI GenBank database. Whole genome sequencing data showed that the genome size of M. hominis MH4246 was calculated as 679,746 bp, with 558 protein-coding sequences and a G + C content of 26.9%. M. hominis MH4246 is resistant to fluoroquinolones and macrolides, harboring mutations in the quinolone resistance-determining regions (QRDRs) (GyrA S153L, ParC S91I and ParE V417I) and 23S rRNA gene (G280A, C1500T, T1548C and T2218C). Multiple virulence determinants, such as tuf, hlyA, vaa, oppA, MHO_0730 and alr genes, were identified. Phylogenetic analysis showed that the closest relative of M. hominis MH4246 was the strain MH-1 recovered from China, which differed by 3490 SNPs. Overall, this study contributes to the comprehension of genomic characteristics, antimicrobial resistance patterns, and the mechanisms underlying the pathogenicity of this pathogen.


Assuntos
Abscesso , Mycoplasma hominis , Humanos , Mycoplasma hominis/genética , Filogenia , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Fluoroquinolonas/farmacologia , Fluoroquinolonas/uso terapêutico
2.
Crit Rev Microbiol ; : 1-31, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38794781

RESUMO

Human Ureaplasma species are being increasingly recognized as opportunistic pathogens in human genitourinary tract infections, infertility, adverse pregnancy, neonatal morbidities, and other adult invasive infections. Although some general reviews have focused on the detection and clinical manifestations of Ureaplasma spp., the molecular epidemiology, antimicrobial resistance, and pathogenesis of Ureaplasma spp. have not been adequately explained. The purpose of this review is to offer valuable insights into the current understanding and future research perspectives of the molecular epidemiology, antimicrobial resistance, and pathogenesis of human Ureaplasma infections. This review summarizes the conventional culture and detection methods and the latest molecular identification technologies for Ureaplasma spp. We also reviewed the global prevalence and mechanisms of antibiotic resistance for Ureaplasma spp. Aside from regular antibiotics, novel antibiotics with outstanding in vitro antimicrobial activity against Ureaplasma spp. are described. Furthermore, we discussed the pathogenic mechanisms of Ureaplasma spp., including adhesion, proinflammatory effects, cytotoxicity, and immune escape effects, from the perspectives of pathology, related molecules, and genetics.

3.
Emerg Infect Dis ; 29(11): 2246-2256, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37877525

RESUMO

Prevalence of carbapenem-resistant Klebsiella pneumoniae (CRKP) has compromised antimicrobial efficacy against severe infections worldwide. To monitor global spread, we conducted a comprehensive genomic epidemiologic study comparing sequences from 21 blaOXA-232-carrying CRKP isolates from China with K. pneumoniae sequence type (ST) 15 strains from 68 countries available in GenBank. Phylogenetic and phylogeographic analyses revealed all blaOXA-232-carrying CRKP isolates belonged to ST15 lineage and exhibited multidrug resistance. Analysis grouped 330 global blaOXA-232-carrying ST15 CRKP strains into 5 clades, indicating clonal transmission with small genetic distances among multiple strains. The lineage originated in the United States, then spread to Europe, Asia, Oceania, and Africa. Most recent common ancestor was traced back to 2000; mutations averaged ≈1.7 per year per genome. Our research helps identify key forces driving global spread of blaOXA-232-carrying CRKP ST15 lineage and emphasizes the importance of ongoing surveillance of epidemic CRKP.


Assuntos
Enterobacteriáceas Resistentes a Carbapenêmicos , Infecções por Klebsiella , Humanos , Carbapenêmicos/farmacologia , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Klebsiella pneumoniae , Filogeografia , Plasmídeos , Filogenia , Genômica , Infecções por Klebsiella/epidemiologia , Infecções por Klebsiella/tratamento farmacológico , beta-Lactamases/genética , Testes de Sensibilidade Microbiana
4.
BMC Infect Dis ; 23(1): 852, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38053032

RESUMO

BACKGROUND: Motor neuron disease (MND) is a fatal neurodegenerative disorder that leads to progressive loss of motor neurons. Chlamydia psittaci (C. psittaci) is a rare etiology of community-acquired pneumonia characterized primarily by respiratory distress. We reported a case of C. psittaci pneumonia complicated with motor neuron disease (MND). CASE PRESENTATION: A 74-year-old male was referred to the Shaoxing Second Hospital at January, 2022 complaining of fever and fatigue for 2 days. The patient was diagnosed of MND with flail arm syndrome 1 year ago. The metagenomic next-generation sequencing (mNGS) of sputum obtained through bedside fiberoptic bronchoscopy showed C. psittaci infection. Then doxycycline was administrated and bedside fiberoptic bronchoscopy was performed to assist with sputum excretion. Computed Tomography (CT) and fiberoptic bronchoscopy revealed a significant decrease in sputum production. On day 24 after admission, the patient was discharged with slight dyspnea, limited exercise tolerance. One month later after discharge, the patient reported normal respiratory function, and chest CT showed significant absorption of sputum. CONCLUSIONS: The mNGS combined with bedside fiberoptic bronchoscopy could timely detect C. psittaci infection. Bedside fiberoptic bronchoscopy along with antibiotic therapy may be effective for C. psittaci treatment.


Assuntos
Chlamydophila psittaci , Doença dos Neurônios Motores , Pneumonia , Psitacose , Masculino , Humanos , Idoso , Psitacose/complicações , Psitacose/diagnóstico , Psitacose/tratamento farmacológico , Brônquios , Doença dos Neurônios Motores/complicações , Doença dos Neurônios Motores/diagnóstico , Dispneia
5.
J Sci Food Agric ; 103(3): 1283-1293, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36087337

RESUMO

BACKGROUND: l-Theanine (LTA) is a biologically active ingredient in tea that shows great potential for regulating lipid metabolism. Bile acids (BA), an important end-product of cholesterol catabolism, participate in the regulation of lipid metabolism and gut microbiota. Here, we investigated the effect of LTA on lipid metabolism and the mechanism by which it regulates BA metabolism and gut microbiota. Male BALB/c mice were treated with LTA for 28 days. RESULTS: Daily LTA doses of 100 and 300 mg kg-1  d-1 altered the gut microbiota in mice, predominantly by decreasing Lactobacillus, Streptococcus, Bacteroides, Clostridium and Enterorhabdus microbes associated with bile-salt hydrolase (BSH) activity, thereby decreasing the activity of BSH and increasing the levels of ileum conjugated BA (such as glycocholic acid (GCA) and lithocholic acid), thereby inhibiting the intestinal farnesoid X receptor (FXR)-fibroblast growth factor 15 (FGF15) signaling pathway. Inhibition of FXR-FGF15 signaling was accompanied by upregulation of cholesterol 7α-hydroxylase (CYP7A1) mRNA and protein expression and increased hepatic production of cholic acid, deoxycholic acid, GCA, glycine cholic acid and glycine ursodeoxycholic acid. Meanwhile, increasing hepatic unconjugated BA upregulated the mRNA and protein expression of liver 3-hydroxy-3-methylglutaryl-CoA reductase and downregulated the mRNA and protein expression of stearoyl-CoA desaturase-1, liver low-density lipoprotein receptor and type B scavenger receptor. Therefore, the serum levels of cholesterol and triglycerides decreased. CONCLUSION: Our findings indicate that LTA regulates lipid metabolism by modulating the gut microbiota and BA metabolism via the FXR-FGF15-CYP7A1 pathway. © 2022 Society of Chemical Industry.


Assuntos
Microbioma Gastrointestinal , Metabolismo dos Lipídeos , Masculino , Camundongos , Animais , Ácidos e Sais Biliares/metabolismo , Fígado/metabolismo , Colesterol/metabolismo , RNA Mensageiro/metabolismo , Camundongos Endogâmicos C57BL , Colesterol 7-alfa-Hidroxilase/genética , Colesterol 7-alfa-Hidroxilase/metabolismo
6.
Anal Bioanal Chem ; 414(17): 4953-4962, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35567611

RESUMO

The improper use of phosgene, either as a chemical warfare agent or a leak during chemical production, causes significant risks to human life and property. Therefore, it is particularly important to develop a rapid and highly selective method for the detection of phosgene. In this article, a highly selective fluorescent sensor ONB with a BODIPY unit as a fluorophore and o-aminophenol as a reactive site was constructed for the selective and rapid detection of phosgene in solution. The ONB-containing nanofibers were sprayed onto a non-woven fabric by electrostatic spinning and cut into test films, which can be used well for the detection of gaseous phosgene. While, there were no reported bio-imaging applications for phosgene detection. In this work, nasal mucosa and lung samples from the mice exposed to gaseous phosgene after dropping the ONB solution through the nasal cavity achieved bio-imaging applications successfully.


Assuntos
Substâncias para a Guerra Química , Fosgênio , Animais , Compostos de Boro , Substâncias para a Guerra Química/toxicidade , Gases/química , Pulmão , Camundongos , Mucosa Nasal , Fosgênio/química , Fosgênio/toxicidade
7.
Int J Mol Sci ; 23(6)2022 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-35328729

RESUMO

Pseudorabies virus (PRV) infection could cause severe histopathological damage via releasing multiple factors, including cytokines, peptides, etc. Here, peptidomic results showed that 129 peptides were identified in PRV-infected mouse lungs and were highly involved in the process of PRV infection. The role of one down-regulated biological peptide (designated as AGDP) during PRV infection was investigated. To verify the expression profiles of AGDP in response to PRV infection, the expression level of the precursor protein of AGDP mRNA was significantly decreased in PRV-infected mouse lungs and cells. The synthesized AGDP-treating cells were less susceptible to PRV challenges than the controls, as demonstrated by the decreased virus production and gE expression. AGDP not only inhibited the expression of TNF-α and IL-8 but also appeared to suppress the extracellular release of high-mobility group box 1 (HMGB1) by inhibiting the output of nuclear HMGB1 in cells. AGDP could also inhibit the degradation of IκBα and the phosphorylation levels of P65 after PRV infection. In total, our results revealed many meaningful peptides involved in PRV infection, thereby enhancing the current understanding of the host response to PRV infection, and how AGDP may serve as a promising candidate for developing novel anti-PRV drugs.


Assuntos
Proteína HMGB1 , Herpesvirus Suídeo 1 , Pseudorraiva , Animais , Citocinas , Pulmão/patologia , Camundongos , Pseudorraiva/tratamento farmacológico
8.
Artigo em Inglês | MEDLINE | ID: mdl-32229497

RESUMO

Antibiotic resistance is a global concern; however, data on antibiotic-resistant Ureaplasma spp. and Mycoplasma hominis are limited in comparison to similar data on other microbes. A total of 492 Ureaplasma spp. and 13 M. hominis strains obtained in Hangzhou, China, in 2018 were subjected to antimicrobial susceptibility testing for levofloxacin, moxifloxacin, erythromycin, clindamycin, and doxycycline using the broth microdilution method. The mechanisms underlying quinolone and macrolide resistance were determined. Meanwhile, a model of the topoisomerase IV complex bound to levofloxacin in wild-type Ureaplasma spp. was built to study the quinolone resistance mutations. For Ureaplasma spp., the levofloxacin, moxifloxacin, and erythromycin resistance rates were 84.69%, 51.44%, and 3.59% in U. parvum and 82.43%, 62.16%, and 5.40% in U. urealyticum, respectively. Of the 13 M. hominis strains, 11 were resistant to both levofloxacin and moxifloxacin, and five strains showed clindamycin resistance. ParC S83L was the most prevalent mutation in levofloxacin-resistant Ureaplasma strains, followed by ParE R448K. The two mutations GyrA S153L and ParC S91I were commonly identified in quinolone-resistant M. hominis A molecular dynamics-refined structure revealed that quinolone resistance-associated mutations inhibited the interaction and reduced affinity with gyrase or topoisomerase IV and quinolones. The novel mutations S21A in the L4 protein and G2654T and T2245C in 23S rRNA and the ermB gene were identified in erythromycin-resistant Ureaplasma spp. As fluoroquinolone resistance in Ureaplasma spp. and Mycoplasma hominis remains high in China, the rational use of antibiotics needs to be further enhanced.


Assuntos
Infecções por Mycoplasma , Quinolonas , Infecções por Ureaplasma , Antibacterianos/farmacologia , China , Farmacorresistência Bacteriana/genética , Humanos , Macrolídeos , Testes de Sensibilidade Microbiana , Infecções por Mycoplasma/tratamento farmacológico , Mycoplasma hominis/genética , Quinolonas/farmacologia , Ureaplasma/genética , Infecções por Ureaplasma/tratamento farmacológico , Ureaplasma urealyticum
9.
Sensors (Basel) ; 20(4)2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-32059557

RESUMO

Unmanned aerial vehicles (UAV) have had significant progress in the last decade, which is applied to many relevant fields because of the progress of aerial image processing and the convenience to explore areas that men cannot reach. Still, as the basis of further applications such as object tracking and terrain classification, semantic image segmentation is one of the most difficult challenges in the field of computer vision. In this paper, we propose a method for urban UAV images semantic segmentation, which utilizes the geographical information of the region of interest in the form of a digital surface model (DSM). We introduce an Affiliated Fusion Conditional Random Field (AF-CRF), which combines the information of visual pictures and DSM, and a multi-scale strategy with attention to improve the segmenting results. The experiments show that the proposed structure performs better than state-of-the-art networks in multiple metrics.

11.
New Microbiol ; 42(4): 225-227, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31305936

RESUMO

Macrolides are widely used for the treatment of Ureaplasma spp. infection. The aim of this study was to investigate possible genetic resistance determinants in Ureaplasma spp. isolates. A total of eleven macrolide- resistant Ureaplasma spp. isolates, recovered from urogenital specimens, were investigated for genetic mechanisms of macrolide resistance. The 23S rRNA operons, as well as L4 and L22 ribosomal protein genes, were amplified and sequenced. Our study identified that the mutation A2066G in the 23S rRNA and four mutations (G361T, A406G, C422T and G196A) in the L22 ribosomal protein, may be responsible for the resistance of Ureaplasma spp. to macrolides, in China.


Assuntos
Antibacterianos , Farmacorresistência Bacteriana , Variação Genética , Macrolídeos , Ureaplasma , Antibacterianos/farmacologia , China , Farmacorresistência Bacteriana/genética , Macrolídeos/farmacologia , Testes de Sensibilidade Microbiana , Mutação , RNA Ribossômico 23S/genética , Proteínas Ribossômicas/genética , Ureaplasma/efeitos dos fármacos , Ureaplasma/genética
12.
Int J Med Microbiol ; 308(7): 819-828, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30033344

RESUMO

Ureaplasma spp. are known to be associated with human genitourinary tract diseases and perinatal diseases and Ureaplasma spp. Lipid-associated membrane proteins (LAMPs) play important roles in their related diseases. However, the exact mechanism underlying pathogenesis of Ureaplasma spp. LAMPs is largely unknown. In this study, we explored the pathogenic mechanisms of Ureaplasma spp. LAMPs by elucidating their role in modulating the cell cycle and related signaling pathways in human monocytic cell U937, which is highly related to the inflammatory and protective effect in infectious diseases. We utilized the two ATCC reference strains (Ureaplasma parvum serovar 3 str. ATCC 27,815 (UPA3) and Ureaplasma urealyticum serovar 8 str. ATCC 27,618 (UUR8)) and nine clinical isolates which including both UPA and UUR to study the effects of Ureaplasma spp. LAMPs on U937 in vitro. We found that LAMPs derived from UUR8 and both UPA and UUR of clinical strains markedly inhibited the cell proliferation, while UPA3 LAMPs suppressed slightly. Besides, the result of flow cytometry analysis indicated all the Ureaplasma spp. LAMPs could arrest U937 cells in G1 phase. Next, we found that the cell cycle arrest was associated with increased levels of p53 and p21, and a concomitant decrease in the levels of CDK2, CDK4, CDK6 and cyclin E1 at both transcriptional and translational levels after treatment with LAMPs derived from UUR8 or clinical strains, while only cyclin E1 was down-regulated after treatment with UPA3 LAMPs. Further study showed that p53 down-regulation had almost no effect on the distribution of cell cycle and the expression of p21. In conclusion, this study demonstrated that LAMPs derived from UUR8 and clinical strains could inhibit the proliferation of U937 cells by inducing G1 cell cycle arrest through increasing the p21 expression in a p53-independent manner, while UPA3 LAMPs could induce the cell cycle arrest slightly. Our study could contribute to the understanding of Ureaplasma spp. pathogenesis, which has potential value for the treatment of Ureaplasma spp. infections.


Assuntos
Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Pontos de Checagem da Fase G1 do Ciclo Celular/fisiologia , Lipoproteínas/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Infecções por Ureaplasma/patologia , Ureaplasma/patogenicidade , Linhagem Celular Tumoral , Proliferação de Células/fisiologia , Ciclina E/biossíntese , Quinase 2 Dependente de Ciclina/biossíntese , Quinase 4 Dependente de Ciclina/biossíntese , Quinase 6 Dependente de Ciclina/biossíntese , Humanos , Proteínas Oncogênicas/biossíntese , Células U937 , Ureaplasma/isolamento & purificação , Doenças Urológicas/microbiologia
13.
Eur J Clin Microbiol Infect Dis ; 37(10): 1957-1963, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30051356

RESUMO

Whether Ureaplasma spp. are a causative agent of male infertility remains controversial. Previous studies concerning Ureaplasma spp. and male infertility have been confined to the species level of Ureaplasma. Currently, an expanded multilocus sequence typing (eMLST) scheme has been established with high discriminatory power. The aim of this study was to use eMLST to explore the distribution of Ureaplasma spp. and to analyze its role in oligozoospermia and semen quality. A total of 480 semen samples were obtained from Chinese infertile males. The associations between Ureaplasma spp. with oligozoospermia and semen characteristics were further evaluated. Phylogenetic analysis revealed that 102 Ureaplasma spp. could be separated into two clusters and seven sub-groups. Within cluster I (U. parvum), eST16 and eST41 were the most frequent clones. For cluster II (U. urealyticum), eST82 and eST147 were the most prevalent clones. Sub-groups A and C belonging to cluster I and sub-group 1 belonging to cluster II showed an association with oligozoospermia, in contrast with the Ureaplasma spp. negative group (P < 0.05). Compared with the negative group, semen motility decreased in sub-group 2, especially for non-progressive motility (P < 0.05). These results indicated that sub-groups A and C belonging to cluster I (U. parvum) and sub-group 1 belonging to cluster II (U. urealyticum) were shown to be associated with oligozoospermia. Sub-group 2 belonging to cluster II may have the ability to impair semen motility, especially for non-progressive motility.


Assuntos
Oligospermia/microbiologia , Análise do Sêmen , Infecções por Ureaplasma/microbiologia , Ureaplasma/classificação , Adulto , Povo Asiático , Técnicas de Tipagem Bacteriana , Humanos , Masculino , Pessoa de Meia-Idade , Tipagem de Sequências Multilocus , Filogenia , Sêmen/microbiologia , Ureaplasma/genética , Ureaplasma/isolamento & purificação
14.
Zhonghua Yi Xue Za Zhi ; 94(2): 100-3, 2014 Jan 14.
Artigo em Chinês | MEDLINE | ID: mdl-24721348

RESUMO

OBJECTIVE: To explore the distribution of Ureaplasma urealyticum (UU) serotypes in cervix secretion and examine the relationship between serotype and host age, clinical phenotypes and vaginal Lactobacilli. METHODS: A total of 444 cervical secretion samples were collected from healthy subjects and 342 cervical secretion samples from females with genital diseases between October and December 2012 at Sir Run Run Shaw Hospital, Zhejiang University School of Medicine. Biovar-typing was performed by PCR based on multiple-banded antigen (MBA) gene. And serotyping was performed by real-time PCR based on specific nucleotide sequences. RESULTS: The positive rate of UU in disease group (62.6%, 214/342) was significantly higher than that in healthy group (44.1%, 196/444, P < 0.05). The main serotypes in both groups were 1, 3, 6, 9 and mixed infection.No significant difference existed between host age and UU serotype (P > 0.05) . The distribution of serotype 3 in disease and Lactobacilli abnormal group was significantly higher than that in healthy and Lactobacilli normal groups (13.1% (28/214) vs 5.1% (10/196) , 12.2% (27/221) vs 5.8% (11/189) , both P < 0.05) whereas the distribution of serotype 6 in disease and Lactobacilli abnormal groups was significantly lower than that in healthy and Lactobacilli normal groups (14.0% (30/214) vs 30.1% (59/196) , 16.3% (36/221) vs 28.0% (53/189) , both P < 0.05). CONCLUSIONS: 1, 3, 6, 9 and mixed infection are the main UU serotypes in female cervix.Serotype 3 and mixed infection may be associated with female genital infection.


Assuntos
Colo do Útero/microbiologia , Doenças Urogenitais Femininas/microbiologia , Infecções por Ureaplasma/microbiologia , Ureaplasma urealyticum/classificação , Adulto , Técnicas de Tipagem Bacteriana , Estudos de Casos e Controles , Feminino , Humanos , Pessoa de Meia-Idade , Sorotipagem , Ureaplasma urealyticum/patogenicidade
15.
Front Psychol ; 15: 1386350, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38845770

RESUMO

Introduction: In the era of the Internet, online digital traces have become a new way to study the online attention of scenic spots and tourists' purchase behavior. The public's information search on major search platforms is a series of manifestations of potential tourists' attention and interest in scenic spots, but there are few studies on how attention, interest and information search affect potential tourists to generate real purchase behavior. Method: This paper selects four dimensions of short video platform, travel website, search engine and social media to comprehensively measure the online attention of high-quality scenic spots in Yunnan Province, and then establishes a gray association analytic hierarchy process based on the relevant variables of the AISAS model to empirically analyze the primary and secondary factors affecting tourists' purchase behavior. Results: (1) From the perspective of the online attention of scenic spots on different platforms, the intensity of the public's scenic spots online attention on the four types of media platforms is in the order of travel websites, search engines, short videos and social media (2) From the perspective of spatial distribution characteristics, the online attention of high-quality scenic spots in Yunnan Province is unevenly distributed, that is, there is a big difference between the attention of higher star scenic spots and their star rating and popularity, while the attention of low-star scenic spots is not much different from their star rating and popularity (3) From the perspective of spatial agglomeration characteristics, the comprehensive online attention of high-quality scenic spots in Yunnan Province presents the spatial agglomeration characteristics of "the multi-core linkage of high-density in the east and north, and sub-high-density in the south" (4) The factors influencing the purchase behavior of potential tourists are sharing experience, attracting attention, generating interest and searching information. Discussion: By exploring the formation mechanism of high-quality scenic spots online attention in Yunnan Province and the mechanism of its spatial differentiation, this study not only enriches the logical chain of "tourism information source → potential tourists → demand driven → tourism information search → travel preference → destination selection → purchase decision → travel experience → real tourists → feelings after traveling → focus on feedback → tourism information source," but also broadens the application scenarios and application boundaries of travel preference theory and AISAS behavior model to a certain extent.

16.
Talanta ; 269: 125448, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38029607

RESUMO

As an important chemical raw material, hydrazine brings convenience to people's lives and provides opportunities for human development. However, the misuse or leakage of hydrazine has brought pollution to the environment, including water, soil and living organisms. At the same time, hydrazine poses a potential threat to human health as a carcinogen. Despite the enormous challenges, it is crucial to develop an effective method to detect hydrazine in environmental samples. In this work, we have synthesized a series of probes based on phenothiazine fluorophore by the introduction of different substituents and developed a novel probe for the detection of hydrazine. The probe is capable of detecting hydrazine in aqueous solutions with high sensitivity and selectivity, and can be easily fabricated into paper test strips for use in in situ samples. In addition, the probe is effective in detecting hydrazine in water, soil, cells, and zebrafish, providing an excellent tool for detecting hydrazine in the environment.


Assuntos
Corantes Fluorescentes , Peixe-Zebra , Animais , Humanos , Corantes Fluorescentes/química , Hidrazinas/química , Fenotiazinas , Água , Solo , Espectrometria de Fluorescência
17.
Infect Drug Resist ; 17: 1251-1258, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38560708

RESUMO

Raoultella planticola is an emerging bacterial pathogen responsible for causing infections in both humans and animals. Unfortunately, sporadic reports of carbapenem-resistant R. planticola (CRRP) have been documented worldwide. Here we first reported the complete genome sequence of a CRRP isolate RP_3045 co-carrying blaIMP-4 and blaSHV-12, recovered from a patient in China, and its genetic relatedness to 82 R. planticola strains deposited in the NCBI GenBank database, sourced from humans, animals, and the environment. Whole-genome sequencing was performed using the Illumina NovaSeq 6000 and Oxford Nanopore MinION platforms. Phylogenetic analysis was also performed and visualized using a single nucleotide polymorphism (SNP)-based strategy. The complete genome of R. planticola strain RP_3045 was determined to be 6,312,961 bp in length, comprising five contigs that included one chromosome and four plasmids. RP_3045 was found to be multidrug-resistant and harbored several antimicrobial resistance genes, including both blaIMP-4 and blaSHV-12 genes located on a single plasmid. The most closely related strain was hkcpe63, recovered from humans in Hong Kong, China, in 2014, with 506 SNP differences. R. planticola strains were distributed globally and exhibited strong associations among isolates obtained from different sectors. This study provides evidence for the potential of R. planticola to disseminate carbapenem resistance across different sectors, highlighting the critical need for active and continuous surveillance of CRRP.

18.
Plant Cell Physiol ; 54(4): 609-21, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23396598

RESUMO

Among the three primary auxin-induced gene families, Auxin/Indole-3-Acetic Acid (Aux/IAA), Gretchen Hagen3 (GH3) and SMALL AUXIN UP RNA (SAUR), the function of SAUR genes remains unclear. Arabidopsis SAUR genes have been phylogenetically classified into three clades. Recent work has suggested that SAUR19 (clade II) and SAUR63 (clade I) promote cell expansion through the modulation of auxin transport. Herein, we present our work on SAUR41, a clade III SAUR gene with a distinctive expression pattern in root meristems. SAUR41 was normally expressed in the quiescent center and cortex/endodermis initials; upon auxin stimulation, the expression was provoked in the endodermal layer. During lateral root development, SAUR41 was expressed in prospective stem cell niches of lateral root primordia and in expanding endodermal cells surrounding the primordia. SAUR41-EGFP (enhanced green fluorescent protein) fusion proteins localized to the cytoplasm. Overexpression of SAUR41 from the Cauliflower mosaic virus 35S promoter led to pleiotropic auxin-related phenotypes, including long hypocotyls, increased vegetative biomass and lateral root development, expanded petals and twisted inflorescence stems. Ectopic SAUR41 proteins were able to promote auxin transport in hypocotyls. Tissue-specific expression of SAUR41 from the PIN1, WOX5, PLT2 and ACR4 promoters induced the formation of new auxin accumulation/signaling peaks above the quiescent centers, whereas tissue-specific expression of SAUR41 from the PIN2 and PLT2 promoters enhanced root gravitropic growth. Cells in the root stem cell niches of these transgenic seedlings were differentially enlarged. The distinctive expression pattern of the SAUR41 gene and the explicit function of SAUR41 proteins implied that further investigations on the loss-of-function phenotypes of this gene in root development and environmental responses are of great interest.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Meristema/citologia , Meristema/metabolismo , Raízes de Plantas/metabolismo , Arabidopsis/citologia , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/fisiologia , Ácidos Indolacéticos , Raízes de Plantas/genética , Plantas Geneticamente Modificadas/citologia , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo
19.
Chemistry ; 19(48): 16170-5, 2013 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-24150978

RESUMO

Iron ORR: An ordered, mesoporous, Fe-porphyrin-like material was created through the nanocasting and pyrolysis of traditional Fe-N4 porphyrins. The resulting nonprecious metal electrocatalyst was used for the oxygen reduction reaction in both alkaline and acidic media.

20.
Dalton Trans ; 52(44): 16297-16302, 2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-37855272

RESUMO

A new mixed anionic compound Cd2TeO3Cl2 with unprecedented [Cd2O6Cl4] octahedral dimers has been synthesized, and millimeter-scale single crystals of Cd2TeO3Cl2 have been grown by the vertical Bridgman method with CdCl2 as the flux. Cd2TeO3Cl2 crystallizes in the centrosymmetric P1̄ (no. 2) space group, and shows a mixed cationic layer structure constituted by distorted [TeO3] motifs, mixed anionic [Cd2O6Cl4] chains, and [Cd2O6Cl4] octahedral dimers. Experimental and theoretical results show that Cd2TeO3Cl2 is a direct band gap compound with an experimental band gap of ∼4.25 eV. Meanwhile, the compound has good optical transmittance in the 3-5 µm atmospheric window. The results indicate that Cd2TeO3Cl2 could be used as a promising mid-IR window material, and could enrich the chemical and structural diversity of oxides.

SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa