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1.
BMC Infect Dis ; 23(1): 372, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37264312

RESUMO

BACKGROUND: Organizing pneumonia (OP) is a rare interstitial lung disease. Secondary organizing pneumonia (SOP) caused by Mycobacterium tuberculosis (MTB) is extremely rare. Migratory MTB-associated SOP is more deceptive and dangerous. When insidious tuberculosis (TB) is not recognized, SOP would be misdiagnosed as cryptogenic organizing pneumonia (COP). Use of steroid hormone alone leads to the progression of TB foci or even death. Clues of distinguishing atypical TB at the background of OP is urgently needed. CASE PRESENTATION: A 56-year-old female patient was hospitalized into the local hospital because of cough and expectoration for more than half a month. Her medical history and family history showed no relation to TB or other lung diseases. Community-acquired pneumonia was diagnosed and anti-infection therapy was initialized but invalid. The patient suffered from continuous weigh loss. More puzzling, the lesions were migratory based on the chest computed tomography (CT) images. The patient was then transferred to our hospital. The immunological indexes of infection in blood and pathogenic tests in sputum and the bronchoalveolar lavage fluid were negative. The percutaneous lung puncture biopsy and pathological observation confirmed OP, but without granulomatous lesions. Additionally, pathogen detection of the punctured lung tissues by metagenomics next generation sequencing test (mNGS) were all negative. COP was highly suspected. Fortunately, the targeted next-generation sequencing (tNGS) detected MTB in the punctured lung tissues and MTB-associated SOP was definitely diagnosed. The combined therapy of anti-TB and prednisone was administrated. After treatment for 10 days, the partial lesions were significantly resorbed and the patient was discharged. In the follow-up of half a year, the patient was healthy. CONCLUSIONS: It is difficult to distinguish SOP from COP in clinical practice. Diagnosis of COP must be very cautious. Transient small nodules and cavities in the early lung image are a clue to consider TB, even though all pathogen tests are negative. tNGS is also a powerful tool to detect pathogen, ensuring prompt diagnosis of TB-related SOP. For clinicians in TB high burden countries, we encourage them to keep TB in mind before making a final diagnosis of COP.


Assuntos
Pneumonia em Organização Criptogênica , Mycobacterium tuberculosis , Pneumonia em Organização , Pneumonia , Tuberculose , Humanos , Feminino , Pessoa de Meia-Idade , Mycobacterium tuberculosis/genética , Pulmão/diagnóstico por imagem , Pulmão/patologia , Pneumonia em Organização Criptogênica/diagnóstico , Pneumonia em Organização Criptogênica/tratamento farmacológico , Pneumonia em Organização Criptogênica/patologia , Pneumonia/complicações , Tuberculose/complicações , Tuberculose/diagnóstico , Tuberculose/tratamento farmacológico
2.
J Environ Sci (China) ; 126: 308-320, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36503759

RESUMO

Energy-saving and efficient monolithic catalysts are hotspots of catalytic purification of industrial gaseous pollutants. Here, we have developed an electrothermal catalytic mode, in which the ignition temperature required for the reaction is provided by Joule heat generated when the current flows through the catalyst. In this paper, Mn/NiAl/NF, Mn/NiFe/NF and Mn/NF metal-based monolithic catalysts were prepared using nickel foam (NF) as the carrier for thermal and electrothermal catalysis of n-heptane. The results indicated that Mn-based monolithic catalysts exhibit high activity in thermal and electrothermal catalysis. Mn/NiFe/NF achieve conversion of n-heptane more than 99% in electrothermal catalysis under a direct-current (DC) power of 6 W, and energy-saving is 54% compared with thermal catalysis. In addition, the results indicated that the introduction of NiAl (or NiFe) greatly enhanced the catalytic activity of Mn/NF, which attributed to the higher specific surface area, Mn3+/Mn4+, Ni3+/Ni2+, adsorbed oxygen species (Oads)/lattice oxygen species (Olatt), redox performance of the catalyst. Electrothermal catalytic activity was significantly higher than thermal catalytic activity before complete conversion, which may be related to electronic effects. Besides, Mn/NiFe/NF has good cyclic and long-term stability in electrothermal catalysis. This paper provided a theoretical basis for applying electrothermal catalysis in the field of VOCs elimination.


Assuntos
Níquel , Óxidos , Compostos de Manganês , Oxigênio
3.
Indian J Microbiol ; 62(4): 550-557, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36458222

RESUMO

We described an operation that co-overexpress interleukin receptor 1 (IL-1R1) and its co-receptor (IL-1R1AcP) genes in wild-type A375·S2 cells in order to increase their sensibility to IL-1. Firstly, laser scanning confocal microscope observed that IL-1R1 could be expressed on the surface of A375·S2 cells. qPCR was performed to estimate the ratio of two genes and result showed the ratio was almost 4.57:1. Then two genes were linked to vectors and co-transfected into A375·S2 cells. qPCR and Western blotting showed the protein content improved markedly. Finally, MTS assay was executed and the sensitivity of A375·S2 cells that co-transfected receptors to IL-1ß increased significantly. Another MTS assay showed the cell activity variation changed significantly (P < 0.05) and the reliability of the experiment was high, indicating that cell line established in this study could be further used for the activity test of IL-1Ra. Supplementary Information: The online version contains supplementary material available at 10.1007/s12088-022-01027-8.

4.
J Neuroinflammation ; 18(1): 108, 2021 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-33971906

RESUMO

BACKGROUND: Interleukin 9 (IL-9), produced mainly by T helper 9 (Th9) cells, has been recognized as an important regulator in multiple sclerosis (MS) and its animal model, experimental autoimmune encephalomyelitis (EAE). Astrocytes respond to IL-9 and reactive astrocytes always associate with blood-brain barrier damage, immune cell infiltration, and spinal injury in MS and EAE. Several long non-coding RNAs (lncRNAs) with aberrant expression have been identified in the pathogenesis of MS. Here, we examined the effects of lncRNA Gm13568 (a co-upregulated lncRNA both in EAE mice and in mouse primary astrocytes activated by IL-9) on the activation of astrocytes and the process of EAE. METHODS: In vitro, shRNA-recombinant lentivirus with glial fibrillary acidic protein (GFAP) promoter were performed to determine the relative gene expression and proinflammatory cytokines production in IL-9 treated-astrocytes using Western blot, real-time PCR, and Cytometric Bead Array, respectively. RIP and ChIP assays were analyzed for the mechanism of lncRNA Gm13568 regulating gene expression. Immunofluorescence assays was performed to measure the protein expression in astrocytes. In vivo, H&E staining and LFB staining were applied to detect the inflammatory cells infiltrations and the medullary sheath damage in spinal cords of EAE mice infected by the recombinant lentivirus. Results were analyzed by one-way ANOVA or Student's t test, as appropriate. RESULTS: Knockdown of the endogenous lncRNA Gm13568 remarkably inhibits the Notch1 expression, astrocytosis, and the phosphorylation of signal transducer and activator of transcription 3 (p-STAT3) as well as the production of inflammatory cytokines and chemokines (IL-6, TNF-α, IP-10) in IL-9-activated astrocytes, in which Gm13568 associates with the transcriptional co-activators CBP/P300 which are enriched in the promoter of Notch1 genes. More importantly, inhibiting Gm13568 with lentiviral vector in astrocytes ameliorates significantly inflammation and demyelination in EAE mice, therefore delaying the EAE process. CONCLUSIONS: These findings uncover that Gm13568 regulates the production of inflammatory cytokines in active astrocytes and affects the pathogenesis of EAE through the Notch1/STAT3 pathway. LncRNA Gm13568 may be a promising target for treating MS and demyelinating diseases.


Assuntos
Astrócitos/imunologia , Encefalomielite Autoimune Experimental/metabolismo , Interleucina-9/metabolismo , RNA Longo não Codificante/imunologia , Receptor Notch1/biossíntese , Fatores de Transcrição de p300-CBP/metabolismo , Animais , Astrócitos/metabolismo , Encefalomielite Autoimune Experimental/imunologia , Encefalomielite Autoimune Experimental/patologia , Feminino , Regulação da Expressão Gênica/imunologia , Interleucina-9/imunologia , Camundongos , Camundongos Endogâmicos C57BL , RNA Longo não Codificante/metabolismo , Receptor Notch1/imunologia , Fatores de Transcrição de p300-CBP/imunologia
5.
Appl Microbiol Biotechnol ; 104(12): 5213-5227, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32303820

RESUMO

Drug-resistant bacteria are becoming an increasingly widespread problem in the clinical setting. The current pipeline of antibiotics cannot provide satisfactory options for clinicians, which brought increasing attention to the development and application of non-traditional antimicrobial substances as alternatives. Metal ions, such as iron and zinc ions, have been widely applied to inhibit pathogens through different mechanisms, including synergistic action with different metabolic enzymes, regulation of efflux pumps, and inhibition of biofilm formation. Compared with traditional metal oxide nanoparticles, iron oxide nanoparticles (IONPs) and zinc oxide nanoparticles (ZnO-NPs) display stronger bactericidal effect because of their smaller ion particle sizes and higher surface energies. The combined utilization of metal NPs (nanoparticles) and antibiotics paves a new way to enhance antimicrobial efficacy and reduce the incidence of drug resistance. In this review, we summarize the physiological roles and bactericidal mechanisms of iron and zinc ions, present the recent progress in the research on the joint use of metal NPs with different antibiotics, and highlight the promising prospects of metal NPs as antimicrobial agents for tackling multidrug-resistant bacteria.


Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Farmacorresistência Bacteriana Múltipla , Íons , Ferro/farmacologia , Zinco/farmacologia , Bactérias/patogenicidade , Nanopartículas Metálicas/química , Testes de Sensibilidade Microbiana , Preparações Farmacêuticas
6.
Glia ; 67(1): 101-112, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30294880

RESUMO

Th17 cells and interleukin-17 (IL-17) have been found to play an important role in the pathology of multiple sclerosis (MS) and its animal model, experimental autoimmune encephalomyelitis (EAE). Response to IL-17, reactive astrocytes accompany with immune cells infiltration and axonal damage in MS/EAE. However, the role and the regulatory mechanism of IL-17-activated astrocytes in inflammation and in the EAE process still remain largely unknown. Here, we elucidated that miR-409-3p and miR-1896, as co-upregulated microRNAs in activated astrocytes and in EAE mice, targeted suppressor of cytokine signaling proteins 3 (SOCS3). Overexpression of miR-409-3p or miR-1896 significantly reduced SOCS3 expression and increased phosphorylation of STAT3 as well as induced the inflammatory cytokines production (IL-1ß, IL-6, IP-10, MCP-1, and KC), CD4+ T cells migration and demyelination, in turn aggravating EAE development. Importantly, the effects of co-overexpression of miR-409-3p and miR-1896 in vitro or in vivo are strongly co-operative. In contrast, simultaneously silenced miR-409-3p and miR-1896 co-operatively ameliorates inflammation and demyelination in the central nervous system of EAE mice. Collectively, our findings highlight that miR-409-3p and miR-1896 co-ordinately promote the production of inflammatory cytokines in reactive astrocytes through the SOCS3/STAT3 pathway and enhance reactive astrocyte-directed chemotaxis of CD4+ T cells, leading to aggravate pathogenesis in EAE mice. Co-inhibition of miR-409-3p and miR-1896 may be a therapeutic target for treating MS and neuroinflammation.


Assuntos
Astrócitos/metabolismo , Encefalomielite Autoimune Experimental/metabolismo , Interleucina-17/toxicidade , MicroRNAs/biossíntese , Fator de Transcrição STAT3/metabolismo , Proteína 3 Supressora da Sinalização de Citocinas/metabolismo , Animais , Astrócitos/efeitos dos fármacos , Astrócitos/imunologia , Citocinas/biossíntese , Citocinas/imunologia , Encefalomielite Autoimune Experimental/imunologia , Feminino , Inflamação/induzido quimicamente , Inflamação/imunologia , Inflamação/metabolismo , Interleucina-17/imunologia , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/imunologia , Fator de Transcrição STAT3/imunologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Proteína 3 Supressora da Sinalização de Citocinas/imunologia
7.
BMC Infect Dis ; 19(1): 764, 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31477038

RESUMO

BACKGROUND: Environmental bacteria, nontuberculous mycobacteria (NTM), are recognized as one of the major human infection pathogens. NTM are prone to be mistaken as multidrug-resistant Mycobacterium tuberculosis and challenge our fight against TB. In addition, treatment of NTM per se is intractable. Remarkably, the distribution of NTM pathogenic species is geographically specific. Thus, it is very important to summarize the prevalent features and clinical symptoms of NTM pulmonary disease. However, In Nanjing district, southeast China, there is no such a report. METHODS: Through investigating electronic medical records and analyzing data of clinical examination system (Lis), we retrospectively summarized the NTM species from 6012 clinical isolates from May 2017 to August 2018, and analyzed the association between NTM species and clinical symptoms. RESULTS: Of 6012 clinical specimens, 1461 (24.3%) could grow in the MGIT 960 broth. Among these positive isolates, 1213 (83%) were M. tuberculosis, 22 (1.5%) were M. bovis, and 226 (15.5%) were NTM. After deducting redundancy, those NTM specimens were confirmed from 154 patients, among which, 87 (56.5%) patients met the full ATS/IDSA NTM disease criteria. The most common etiologic agent was M. intracellulare (70.1%). NTM infection was associated with age, based on which 68.6% male patients and 77.8% female patients were over 50 years old. The older patients were more likely to have hemoptysis, but the younger patients were more likely to manifest chest congestion. Male patients were more likely to have shortness of breath and females were more likely to have hemoptysis. The most common radiographic presentation of NTM pulmonary disease was bronchiectasis, accounting for 39.1%. Remarkably, multiple and thin-walled cavities were outstanding. The most frequent comorbidity of NTM disease was previous tuberculosis (64%), followed by clinical bronchiectasis (19.5%), HIV (19.5%), and 6.9% chronic obstructive pulmonary disease (COPD). There was no association between NTM species and clinical symptoms. CONCLUSION: This study retrospectively investigated the prevalence of NTM pulmonary disease in Nanjing district, southeast China. Similar to Beijing area, north China, M. intracellulare was the major pathogenic NTM species. Clinical symptoms of the disease were not species-specific. Previous TB and HIV infection immensely enhanced risk of NTM disease.


Assuntos
Pneumopatias/diagnóstico , Pneumopatias/epidemiologia , Infecções por Mycobacterium não Tuberculosas/diagnóstico , Infecções por Mycobacterium não Tuberculosas/epidemiologia , Micobactérias não Tuberculosas/isolamento & purificação , Adulto , Idoso , Idoso de 80 Anos ou mais , Bronquiectasia/diagnóstico , Bronquiectasia/epidemiologia , Bronquiectasia/microbiologia , China/epidemiologia , Comorbidade , Feminino , Infecções por HIV/epidemiologia , Infecções por HIV/microbiologia , Humanos , Pneumopatias/microbiologia , Masculino , Pessoa de Meia-Idade , Infecções por Mycobacterium não Tuberculosas/microbiologia , Micobactérias não Tuberculosas/classificação , Prevalência , Doença Pulmonar Obstrutiva Crônica/complicações , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Infecções Respiratórias/diagnóstico , Infecções Respiratórias/epidemiologia , Infecções Respiratórias/microbiologia , Estudos Retrospectivos , Adulto Jovem
8.
Cell Physiol Biochem ; 45(5): 1986-1998, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29518786

RESUMO

BACKGROUND/AIMS: Multiple sclerosis (MS) is an autoimmune disease in the central nervous system associated with demyelination and axonal injury. Astrocyte activation is involved in the pathogenesis of MS and experimental autoimmune encephalomyelitis (EAE), an animal model of MS. This study was designed to find potential lncRNAs in EAE mice and activated astrocytes. METHODS: we performed microarray analysis of lncRNAs from the brain tissues of EAE mice and primary mouse astrocytes treated with IL-9(50 ng/ml). 12 lncRNAs were validated through real-time PCR. Gene ontology and KEGG pathway analysis were applied to explore the potential functions of lncRNAs. RESULTS: Differentially expressed 3300 lncRNAs and 3250 mRNAs were in the brain tissues of EAE mice, and 3748 lncRNAs and 3332 mRNAs were in activated astrocytes. Notably, there were 2 co-up-regulated lncRNAs and 3 co-down-regulated lncRNAs both in the brain tissues of EAE mice and in activated astrocytes, including Gm14005, Gm12478, mouselincRNA1117, AK080435, and mouselincRNA0681, which regulate the ER calcium flux kinetics, zinc finger protein and cell apoptosis. Similarly, there were 7 mRNAs co-up-regulated and 2 mRNAs co-down-regulated both in vivo and in vitro. Gene ontology and KEGG pathway analysis showed that the biological functions of differentially expressed mRNAs were associated with metabolism, development and inflammation. The results of realtime PCR validation were consistent with the data from the microarrays. CONCLUSIONS: Our data uncovered the expression profiles of lncRNAs and mRNAs in vivo and in vitro, which may help delineate the mechanisms of astrocyte activation during MS/EAE process.


Assuntos
Regulação para Baixo/efeitos dos fármacos , Encefalomielite Autoimune Experimental/patologia , Interleucina-9/farmacologia , RNA Longo não Codificante/metabolismo , RNA Mensageiro/metabolismo , Regulação para Cima/efeitos dos fármacos , Animais , Astrócitos/citologia , Astrócitos/efeitos dos fármacos , Astrócitos/metabolismo , Encéfalo/metabolismo , Encéfalo/patologia , Células Cultivadas , Modelos Animais de Doenças , Encefalomielite Autoimune Experimental/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Análise de Sequência com Séries de Oligonucleotídeos , RNA Longo não Codificante/genética , Reação em Cadeia da Polimerase em Tempo Real , Medula Espinal/metabolismo , Medula Espinal/patologia
9.
ACS Nano ; 18(23): 15239-15248, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38807482

RESUMO

Simple magnesium (Mg) salt solutions are widely considered as promising electrolytes for next-generation rechargeable Mg metal batteries (RMBs) owing to the direct Mg2+ storage mechanism. However, the passivation layer formed on Mg metal anodes in these electrolytes is considered the key challenge that limits its applicability. Numerous complex halogenide additives have been introduced to etch away the passivation layer, nevertheless, at the expense of the electrolyte's anodic stability and cathodes' cyclability. To overcome this dilemma, here, we design an electrolyte with a weakly coordinated solvation structure which enables passivation-free Mg deposition while maintaining a high anodic stability and cathodic compatibility. In detail, we successfully introduce a hexa-fluoroisopropyloxy (HFIP-) anion into the solvation structure of Mg2+, the weakly [Mg-HFIP]+ contact ion pair facilitates Mg2+ transportation across interfaces. As a consequence, our electrolyte shows outstanding compatibility with the RMBs. The Mg||PDI-EDA and Mg||Mo6S8 full cells use this electrolyte demonstrating a decent capacity retention of ∼80% over 400 cycles and 500 cycles, respectively. This represents a leap in cyclability over simple electrolytes in RMBs while the rest can barely cycle. This work offers an electrolyte system compatible with RMBs and brings deeper understanding of modifying the solvation structure toward practical electrolytes.

10.
Front Immunol ; 15: 1407826, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38903523

RESUMO

Background: We aimed to evaluate the efficacy, safety, and immunogenicity of a SARS-CoV-2 mRNA vaccine (Omicron BA.5) LVRNA012 given as the booster in immunized but SARS-CoV-2 infection-free adults in China. Methods: This is a single-center, randomized, double-blind, placebo-controlled phase 3 clinical trial enrolling healthy adult participants (≥18 years) who had completed two or three doses of inactivated COVID-19 vaccines at least 6 months before, in Bengbu, Anhui province, China. Eligible participants were randomly assigned (1:1) to receive a booster intramuscular vaccination with an LVRNA012 vaccine (100ug) or placebo. The primary endpoint was the protective efficacy of a booster dose of the LVRNA012 vaccine or placebo against symptomatic COVID-19 of any severity 14 days after vaccination. Laboratory-confirmed COVID-19 infections were identified from 14 days to 180 days after intervention, with active surveillance for symptomatic illness 8 times per month between 7 to 90 days and at least once per month between 90 to 180 days after intervention. Results: 2615 participants were recruited and randomly assigned in a 1:1 ratio to either the vaccine group (1308) or the placebo group (1307). A total of 141 individuals (46 in the LVRNA012 group and 95 in the placebo group) developed symptomatic COVID-19 infection 14 days after the booster immunization, showing a vaccine efficacy of 51.9% (95% CI, 31.3% to 66.4%). Most infections were detected 90 days after intervention during a period when XBB was prevalent in the community. Adverse reactions were reported by 64% of participants after the LVRNA012 vaccination, but most of them were mild or moderate. The booster vaccination with the LVRNA012 mRNA vaccine could significantly enhance neutralizing antibody titers against the Omicron variant XBB.1.5 (GMT 132.3 [99.8, 175.4]) than did those in the placebo group (GMT 12.5 [8.4, 18.7]) at day 14 for the previously immunized individuals. Conclusion: The LVRNA012 mRNA vaccine is immunogenic, and shows robust efficacy in preventing COVID-19 during the omicron-predominate period. Clinical trial registration: ClinicalTrials.gov, identifier NCT05745545.


Assuntos
Anticorpos Antivirais , Vacinas contra COVID-19 , COVID-19 , Imunização Secundária , Imunogenicidade da Vacina , SARS-CoV-2 , Humanos , Vacinas contra COVID-19/imunologia , Vacinas contra COVID-19/efeitos adversos , Vacinas contra COVID-19/administração & dosagem , Masculino , Feminino , COVID-19/prevenção & controle , COVID-19/imunologia , Adulto , Método Duplo-Cego , SARS-CoV-2/imunologia , Pessoa de Meia-Idade , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Vacinas de mRNA , Eficácia de Vacinas , Adulto Jovem , China , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/imunologia , Vacinas Sintéticas/imunologia , Vacinas Sintéticas/efeitos adversos , Vacinas Sintéticas/administração & dosagem
11.
Front Microbiol ; 15: 1397830, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38784808

RESUMO

The rise of antimicrobial resistance in ESKAPEE pathogens poses significant clinical challenges, especially in polymicrobial infections. Bacteriophage-derived endolysins offer promise in combating this crisis, but face practical hurdles. Our study focuses on engineering endolysins from a Klebsiella pneumoniae phage, fusing them with ApoE23 and COG133 peptides. We assessed the resulting chimeric proteins' bactericidal activity against ESKAPEE pathogens in vitro. ApoE23-Kp84B (CHU-1) reduced over 3 log units of CFU for A. baumannii, E. faecalis, K. pneumoniae within 1 h, while COG133-Kp84B (CHU-2) showed significant efficacy against S. aureus. COG133-L1-Kp84B, with a GS linker insertion in CHU-2, exhibited outstanding bactericidal activity against E. cloacae and P. aeruginosa. Scanning electron microscopy revealed alterations in bacterial morphology after treatment with engineered endolysins. Notably, CHU-1 demonstrated promising anti-biofilm and anti-persister cell activity against A. baumannii and E. faecalis but had limited efficacy in a bacteremia mouse model of their coinfection. Our findings advance the field of endolysin engineering, facilitating the customization of these proteins to target specific bacterial pathogens. This approach holds promise for the development of personalized therapies tailored to combat ESKAPEE infections effectively.

12.
Antibiotics (Basel) ; 13(3)2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38534713

RESUMO

Antimicrobial peptides (AMPs) hold promise as alternatives to combat bacterial infections, addressing the urgent global threat of antibiotic resistance. COG1410, a synthetic peptide derived from apolipoprotein E, has exhibited potent antimicrobial properties against various bacterial strains, including Mycobacterium smegmatis. However, our study reveals a previously unknown resistance mechanism developed by M. smegmatis against COG1410 involving ClpC. Upon subjecting M. smegmatis to serial passages in the presence of sub-MIC COG1410, resistance emerged. The comparative genomic analysis identified a point mutation in ClpC (S437P), situated within its middle domain, which led to high resistance to COG1410 without compromising bacterial fitness. Complementation of ClpC in mutant restored bacterial sensitivity. In-depth analyses, including transcriptomic profiling and in vitro assays, uncovered that COG1410 interferes with ClpC at both transcriptional and functional levels. COG1410 not only stimulated the ATPase activity of ClpC but also enhanced the proteolytic activity of Clp protease. SPR analysis confirmed that COG1410 directly binds with ClpC. Surprisingly, the identified S437P mutation did not impact their binding affinity. This study sheds light on a unique resistance mechanism against AMPs in mycobacteria, highlighting the pivotal role of ClpC in this process. Unraveling the interplay between COG1410 and ClpC enriches our understanding of AMP-bacterial interactions, offering potential insights for developing innovative strategies to combat antibiotic resistance.

13.
Emerg Microbes Infect ; 13(1): 2332660, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38678636

RESUMO

Effectiveness of heterologous booster regimes with ad5 vectored COVID-19 vaccine in a large, diverse population during the national-scale outbreak of SARS-CoV-2 omicron predominance in China has not been reported, yet. We conducted a large-scale cohort-control study in six provinces in China, and did a retrospective survey on the COVID-19 attack risk during this outbreak. Participant aged ≥18 years in five previous trials who were primed with 1 to 3 doses of ICV received heterologous booster with either intramuscular or orally inhaled ad5 vectored COVID-19 vaccine were included in the heterologous-trial cohort. We performed propensity score-matching at a ratio of 1:4 to match participants in the heterologous-trial cohort individually with the community individuals who received three-dose of ICV as a control (ICV-community cohort). From February 4 to April 10, 2023, 41504 (74.5%) of 55710 individuals completed the survey. The median time since the most recent vaccination to the onset of the symptoms of COVID-19 was 303.0 days (IQR 293.0-322.0). The attack rate of COVID-19 in the heterologous-trial cohort was 55.8%, while that in the ICV-community cohort was 64.6%, resulting in a relative effectiveness of 13.7% (95% CI 11.9 to 15.3). In addition, a higher relative effectiveness against COVID-19 associated outpatient visits, and admission to hospital was demonstrated, which was 25.1% (95% CI 18.9 to 30.9), and 48.9% (95% CI 27.0 to 64.2), respectively. The heterologous booster with ad5 vectored COVID-19 vaccine still offered some additional protection in preventing COVID-19 breakthrough infection versus homologous three-dose regimen with ICV, 10 months after vaccination.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Surtos de Doenças , Imunização Secundária , SARS-CoV-2 , Humanos , Vacinas contra COVID-19/administração & dosagem , Vacinas contra COVID-19/imunologia , COVID-19/prevenção & controle , COVID-19/epidemiologia , China/epidemiologia , Estudos Retrospectivos , Masculino , SARS-CoV-2/imunologia , SARS-CoV-2/genética , Adulto , Feminino , Pessoa de Meia-Idade , Surtos de Doenças/prevenção & controle , Vacinas de Produtos Inativados/administração & dosagem , Vacinas de Produtos Inativados/imunologia , Idoso , Adulto Jovem , Eficácia de Vacinas
14.
Int J Antimicrob Agents ; 64(2): 107220, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38810939

RESUMO

Phage therapy offers a promising approach to combat the growing threat of antimicrobial resistance. Yet, key questions remain regarding dosage, administration routes, combination therapy, and the causes of therapeutic failure. In this study, we focused on a novel lytic phage, ФAb4B, which specifically targeted the Acinetobacter baumannii strains with KL160 capsular polysaccharide, including the pan-drug resistant A. baumannii YQ4. ФAb4B exhibited the ability to effectively inhibit biofilm formation and eradicate mature biofilms independently of dosage. Additionally, it demonstrated a wide spectrum of antibiotic-phage synergy and did not show any cytotoxic or haemolytic effects. Continuous phage injections, both intraperitoneally and intravenously over 7 d, showed no acute toxicity in vivo. Importantly, phage therapy significantly improved neutrophil counts, outperforming ciprofloxacin. However, excessive phage injections suppressed neutrophil levels. The combinatorial treatment of phage-ciprofloxacin rescued 91% of the mice, a superior outcome compared to phage alone (67%). The efficacy of the combinatorial treatment was independent of phage dosage. Notably, prophylactic administration of the combinatorial regimen provided no protection, but even when combined with a delayed therapeutic regimen, it saved all the mice. Bacterial resistance to the phage was not a contributing factor to treatment failure. Our preclinical study systematically describes the lytic phage's effectiveness in both in vitro and in vivo settings, filling in crucial details about phage treatment against bacteriemia caused by A. baumannii, which will provide a robust foundation for the future of phage therapy.

15.
Chirality ; 25(6): 355-60, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23661341

RESUMO

Triadimenol is a widely used triazole fungicide and consists of four stereoisomers with 1R,2S, 1S,2R, 1R,2R, and 1S,2S configurations. The trans-enantiomeric pair (1R,2S-isomer and 1S,2R-isomer) is also called triadimenol-A and the cis-enantiomeric pair (1R,2R-isomer and 1S,2S-isomer) triadimenol-B. In this study, the stereoselective degradation and chiral stability of triadimenol in two soils were investigated in details. The dissipation of technical triadimenol, a 6:1 mixture of triadimenol-A and triadimenol-B, showed significant epimerization from triadimenol-A to triadimenol-B occurred along with the dissipation process. The degradation exhibited some stereoselectivity, resulting in a concentration order of 1S,2S > 1R,2R > 1R,2S > 1S,2R or 1S,2S > 1R,2R > 1S,2R > 1R,2S at the end of the 100 days incubation for Baoding soil or Wuhan soil, respectively. Further incubation of triadimenol-B revealed no epimerization, i.e. triadimenol-B was configurationally stable in soil, and 1R,2R-triadimenol degraded slightly slower in the former part and slightly faster in the later part of the incubation than 1S,2S-triadimenol. Moreover, by incubation of enantiopure 1S,2R-triadimenol and 1R,2S-triadimenol, the results documented the epimerization for each enantiomer occurred at both C-1 and C-2 positions. Finally, the present work also documented that the enantiomerization reaction for all the four stereoisomers was nearly negligible in the soils.


Assuntos
Fungicidas Industriais/química , Microbiologia do Solo , Solo/química , Triazóis/química , Estrutura Molecular , Estereoisomerismo , Triazóis/classificação
16.
Infect Drug Resist ; 16: 1801-1812, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37013167

RESUMO

Background: Drug-resistant tuberculosis (TB) is an emerging threat to public health worldwide. Antimicrobial peptide (AMP) is a promising solution to solve the antimicrobial resistance crisis. The apolipoprotein E mimetic peptide COG1410 has been confirmed to simultaneously have neuroprotective, anti-inflammatory, and antibacterial activity. However, whether it is effective to inhibit growth of mycobacteria has not been investigated yet. Methods: The peptide COG1410 was synthesized with conventional solid-phase peptide synthesis and qualified by HPLC and mass spectrometry. Micro-dilution method was used to determine the minimal inhibitory concentration. A time-kill assay was used to determine the bactericidal dynamics of antimicrobial peptide and relative antibiotics. Static biofilm formation was conducted in 24-well plate and the biofilm was separated from planktonic cells and collected. The mechanism of action of COG1410 was explored by TEM observation and ATP leak assay. The localization of COG1410 was observed by confocal laser scan microscopy. The drug-drug interaction was determined by a checkerboard assay. Results: COG1410 was a potent bactericidal agent against M. smegmatis in vitro and within the macrophages with MIC 16 µg/mL, but invalid against M. abscess and M. tuberculosis. A time-kill assay showed that COG1410 killed M. smegmatis as potent as clarithromycin, but faster than LL-37, another short synthetic cationic peptide. 1× MIC COG1410 almost reduced 90% biofilm formation of M. smegmatis. Additionally, COG1410 was able to penetrate the cell membrane of macrophage and inhibit intracellular M. smegmatis growth. TEM observation and ATP leak assay found that COG1410 disrupted cell membrane and caused release of cell contents. Confocal fluorescence microscopy showed that FITC-COG1410 aggregated around cell membrane instead of entering the cytoplasm. Although COG1410 had relative high cytotoxicity, it exhibited strong additive interaction with regular anti-TB antibiotics, which reduced the working concentration of COG1410 and expanding safety window. After 30 passages, there was no induced drug resistance for COG1410. Conclusion: COG1410 was a novel and potent AMP against M. smegmatis by disrupting the integrity of cell membrane.

17.
Nat Commun ; 14(1): 8042, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38052844

RESUMO

The respiratory system, especially the lung, is the key site of pathological injury induced by SARS-CoV-2 infection. Given the low feasibility of targeted delivery of antibodies into the lungs by intravenous administration and the short half-life period of antibodies in the lungs by intranasal or aerosolized immunization, mRNA encoding broadly neutralizing antibodies with lung-targeting capability can perfectly provide high-titer antibodies in lungs to prevent the SARS-CoV-2 infection. Here, we firstly identify a human monoclonal antibody, 8-9D, with broad neutralizing potency against SARS-CoV-2 variants. The neutralization mechanism of this antibody is explained by the structural characteristics of 8-9D Fabs in complex with the Omicron BA.5 spike. In addition, we evaluate the efficacy of 8-9D using a safe and robust mRNA delivery platform and compare the performance of 8-9D when its mRNA is and is not selectively delivered to the lungs. The lung-selective delivery of the 8-9D mRNA enables the expression of neutralizing antibodies in the lungs which blocks the invasion of the virus, thus effectively protecting female K18-hACE2 transgenic mice from challenge with the Beta or Omicron BA.1 variant. Our work underscores the potential application of lung-selective mRNA antibodies in the prevention and treatment of infections caused by circulating SARS-CoV-2 variants.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Animais , Camundongos , Feminino , Anticorpos Amplamente Neutralizantes , SARS-CoV-2/genética , COVID-19/prevenção & controle , Anticorpos Neutralizantes , Camundongos Transgênicos , RNA Mensageiro/genética , Pulmão , Anticorpos Antivirais , Glicoproteína da Espícula de Coronavírus/genética
18.
Chirality ; 24(7): 552-7, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22566128

RESUMO

The enantioselective degradation of quizalofop-ethyl and its metabolite quizalofop-acid in two soils, a Wuhan acidic soil and a Baoding alkaline soil, was investigated. The dissipation of quizalofop-ethyl consisted of two phases, a rapidly deceasing first phase that lasted 1 day and a slowly decreasing second phase that extended till the end of the incubation. It is shown that S-quizalofop-ethyl degraded slightly faster than R-quizalofop-ethyl in the two soils. Further incubation of enantiopure enaniomers showed that quizalofop-ethyl was configurationally stable in soil. Quizalofop-acid was produced quickly, and its amount reached a maximum at 1-6 days time and then decreased slowly with half-lives ranging from 11 to 21 days. The results also showed that quizalofop-acid degraded faster in the acidic Wuhan soil than in the alkaline Baoding soil. At last, significant enantiomerization from S-quizalofop-acid to R-quizalofop-acid was observed, and the enantiomerization was fast, resulting in residues enriched with R-quizalofop-acid whatever racemic quizalofop-ethyl or pure enantiomers were initially applied in the soils.


Assuntos
Propionatos/química , Quinoxalinas/química , Solo/química , Concentração de Íons de Hidrogênio , Propionatos/metabolismo , Quinoxalinas/metabolismo , Estereoisomerismo , Especificidade por Substrato
19.
Environ Sci Pollut Res Int ; 29(37): 55367-55399, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35672638

RESUMO

With the awakening of environmental awareness, the importance of air quality to human health and the proper functioning of social mechanisms is becoming increasingly prominent. The low cost and high efficiency of catalytic technique makes it a natural choice for achieving deep air purification. Stainless steel alloys have demonstrated their full potential for application in a variety of catalytic fields. The diversity of 3D networks or fibrous structures increases the turbulence within the heterogeneous catalysis, balance the temperature distribution in the reaction bed and, in combination with a highly thermally conductive skeleton, avoid agglomeration and deactivation of the active components; corrosion resistance and thermal stability are adapted to highly endothermic/exothermic or corrosive reaction environments; oxide layers formed by bulk transition metals activated by thermal treatment or etching can significantly alter the physico-chemical properties between the substrate and active species, further improving the stability of stainless steel catalysts; suitable electronic conductivity can be applied to the electrothermal catalysis, which is expected to provide guidance for the reduction of intermittent emission exhausts and the storage of renewable energy. The current applications of stainless steel as catalyst or support in the air purification have covered soot particle capture and combustion, catalytic oxidation of VOCs, SCR, and air sterilization. This paper summarizes several preparation methods and presents the relationships between the preparation process and the activity, and reviews its application and the current status of research in atmospheric environmental management, proposing the advantages and challenges of the stainless steel-based catalysts.


Assuntos
Poluição do Ar , Aço Inoxidável , Poluição do Ar/prevenção & controle , Catálise , Corrosão , Humanos , Fuligem/química , Aço Inoxidável/química
20.
ACS Nano ; 16(10): 17097-17106, 2022 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-36149273

RESUMO

Molybdenum trioxide has served as a promising cathode material of rechargeable magnesium batteries (RMBs), because of its rich valence states and high theoretical capacity; yet, it still suffers from sluggish (de)intercalation kinetics and inreversible structure change for highly polarized Mg2+ in the interlayer and intralayer of structure. Herein, F- substitutional and H+ interstitial doping is proposed for α-MoO3 materials (denoted HMoOF) by the intralayer/interlayer engineering strategy to boost the performance of RMBs. F- substitutional doping generates molybdenum vacancies along the Mo-O-□ or Mo-F-□ configurations (where □ represents the cationic vacancy) for unlocking the inactive basal plane of the layered crystal structure, and it further accelerates Mg2+ diffusion along the b-axis. Interstitial-doped H+ can expand interlayer spacing for reducing Mg2+ energy barrier along the ac plane and serve as a "pillar" to stabilize the interlayer structure. Moreover, anion and cation dual doping trigger shallow impurity levels (acceptors levels and donor levels), which helps to easily acquire the electrons from the valence band and donate the electrons to the conduction band. Consequently, the HMoOF electrode exhibits a high reversible capacity (241 mA h g-1 at 0.1 A g-1), an excellent rate capability (137.4 mAh g-1 at 2 A g-1), and a long cycling stability (capacity retention of 98% after 800 cycles at 1 A g-1) in RMBs. This work affords meaningful insights in layered materials for developing high-kinetics and long-life RMBs.

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