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1.
J Cell Mol Med ; 28(12): e18440, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38890792

RESUMO

Hepatitis B virus (HBV) damages liver cells through abnormal immune responses. Mitochondrial metabolism is necessary for effector functions of white blood cells (WBCs). The aim was to investigate the altered counts and mitochondrial mass (MM) of WBCs by two novel indicators of mitochondrial mass, MM and percentage of low mitochondrial membrane potential, MMPlow%, due to chronic HBV infection. The counts of lymphocytes, neutrophils and monocytes in the HBV infection group were in decline, especially for lymphocyte (p = 0.034) and monocyte counts (p = 0.003). The degraded MM (p = 0.003) and MMPlow% (p = 0.002) of lymphocytes and MM (p = 0.005) of monocytes suggested mitochondrial dysfunction of WBCs. HBV DNA within WBCs showed an extensive effect on mitochondria metabolic potential of lymphocytes, neutrophils and monocytes indicated by MM; hepatitis B e antigen was associated with instant mitochondrial energy supply indicated by MMPlow% of neutrophils; hepatitis B surface antigen, antiviral therapy by nucleos(t)ide analogues and prolonged infection were also vital factors contributing to WBC alterations. Moreover, degraded neutrophils and monocytes could be used to monitor immune responses reflecting chronic liver fibrosis and inflammatory damage. In conclusion, MM combined with cell counts of WBCs could profoundly reflect WBC alterations for monitoring chronic HBV infection. Moreover, HBV DNA within WBCs may be a vital factor in injuring mitochondria metabolic potential.


Assuntos
Vírus da Hepatite B , Hepatite B Crônica , Mitocôndrias , Humanos , Hepatite B Crônica/virologia , Hepatite B Crônica/patologia , Masculino , Feminino , Vírus da Hepatite B/patogenicidade , Adulto , Mitocôndrias/metabolismo , Pessoa de Meia-Idade , Contagem de Leucócitos , Leucócitos/metabolismo , DNA Viral/sangue , Potencial da Membrana Mitocondrial , Monócitos/metabolismo , Monócitos/imunologia , Monócitos/virologia , Monócitos/patologia , Neutrófilos/metabolismo , Neutrófilos/imunologia
2.
Exp Ther Med ; 26(2): 404, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37522054

RESUMO

Uncommon Microascus cirrosus (M. cirrosus) species have been reported to cause an increasing number of subcutaneous and invasive fungal infections worldwide; since the first human infection was reported in 1992, seven cases have been reported in PubMed. The present study reports a novel genotype named M. cirrosus SZ 2021 isolated from a patient undergoing hematopoietic stem cell transplantation, who exhibited extensive drug resistance and suffered a fatal pulmonary infection. This isolated M. cirrosus was cultured and determined by morphological observation, multi-locus sequence typing, matrix-assisted laser desorption and ionization time-of-flight mass spectrometry, and whole genome sequencing by next-generation sequencing. The whole nucleotide sequence (32.61 Mb) has been uploaded in the NCBI database (PRJNA835605). In addition, M. cirrosus SZ 2021 was not sensitive to the commonly used antifungal drugs, including fluconazole, amphotericin B, 5-flucytosine and caspofungin. The current literature on human infections by M. cirrosus was reviewed to closely define the comprehensive clinical characteristics and etiological identification. In brief, the present study identified a new M. cirrosus and summarized the clinical characteristics of fungal pneumonia by M. cirrosus species. Complete laboratory identification methods from morphology to gene sequencing were also established for an improved etiological identification and further investigation into the real prevalence of invasive pneumonia by M. cirrosus.

3.
Infect Dis Ther ; 12(4): 1175-1187, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36988865

RESUMO

INTRODUCTION: Clinical metagenomic next-generation sequencing (mNGS) has proven to be a powerful diagnostic tool in pathogen detection. However, its clinical utility has not been thoroughly evaluated. METHODS: In this single-center prospective study at the First Affiliated Hospital of Soochow University, a total of 228 samples from 215 patients suspected of having acute or chronic infections between June 2018 and December 2018 were studied. Samples that met the mNGS quality control (QC) criteria (N = 201) were simultaneously analyzed using conventional tests (CTs), including multiple clinical microbiological tests and real-time PCR (if applicable). RESULTS: Pathogen detection results of mNGS in the 201 QC-passed samples were compared to CTs and exhibited a sensitivity of 98.8%, specificity of 38.5%, and accuracy of 87.1%. Specifically, 109 out of 160 (68.1%) CT+/mNGS+ samples exhibited concordant results at the species/genus level, 25 samples (15.6%) showed overlapping results, while the remaining 26 samples (16.3%) had discordant results between the CT and mNGS assays. In addition, mNGS could identify pathogens at the species level, whereas only the genera of some pathogens could be identified by CT. In this cohort, mNGS results were used to guide treatment plans in 24 out of 41 cases that had available follow-up information, and the symptoms were improved in over 70% (17/24) of them. CONCLUSION: Our data demonstrated the analytic performance of our mNGS pipeline for pathogen detection using a large clinical cohort and strongly supports the notion that in clinical practice, mNGS represents a valuable supplementary tool to CTs to rapidly determine etiological factors of various types of infection and to guide treatment decision-making.

4.
Rev Med Virol ; 33(2): e2415, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36597202

RESUMO

Viruses can create a unique cellular environment that facilitates replication and transmission. Sphingosine kinases (SphKs) produce sphingosine-1-phosphate (S1P), a bioactive sphingolipid molecule that performs both physiological and pathological effects primarily by activating a subgroup of the endothelial differentiation gene family of G-protein coupled cell surface receptors known as S1P receptors (S1PR1-5). A growing body of evidence indicates that the SphK/S1P axis is crucial for regulating cellular activities in virus infections like respiratory viruses, enteroviruses, hepatitis viruses, herpes viruses, and arboviruses replicate. Depending on the type of virus, pro- or anti-viral activities of the SphK/S1P axis sometimes rely on the host immune system and sometimes directly through intracellular signalling pathways or cell proliferation. Recent research has shown novel roles of S1P and SphK in viral replication. Sphingosine kinase isoforms (SphK1 and SphK2) levels can be manipulated by several viruses to promote the effects that are expected. Regulation of cellular signalling pathways plays a significant role in the mechanism. The purpose of this review is to provide insight of the characters played by the SphK/S1P axis throughout diverse viral infection processes. We then assess potential therapeutic methods that are based on S1P signalling and metabolism during viral infections.


Assuntos
Viroses , Vírus , Humanos , Esfingosina/metabolismo , Transdução de Sinais/fisiologia , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Lisofosfolipídeos/metabolismo , Replicação Viral
5.
Exp Biol Med (Maywood) ; 247(2): 97-105, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34632855

RESUMO

Plasma cell mastitis is a benign suppurative disease of the breast, lack of specific clinical manifestations, which is easy to be misdiagnosed and mistreated, often confused with mastitis, breast cancer (BC), and other diseases. Thus, we aimed to establish a combined model of promoting diagnostic accuracy of plasma cell mastitis by contrast-enhanced ultrasound (CEUS) patterns and routine blood cell analysis. Eighty-eight plasma cell mastitis, 91 breast cancer, and 152 other benign breast diseases' patients grouped according to pathological diagnosis underwent CEUS and blood cell analysis examination; 100 healthy female donors were involved. All the plasma cell mastitis and breast cancer patients presented hyperenhancement of CEUS breast lesions compared with others. The majority of plasma cell mastitis (65/88) showed perfusion defect of CEUS patterns with smooth edge (56/65) and multiple lesions (49/65); in contrast, fewer breast cancer patients (30/91) displayed perfusion defect. White blood cell count (WBC), neutrophils, and neutrophils/lymphocytes ratio of blood cell analysis in plasma cell mastitis patients increased significantly compared with other patients (P < 0.0001). Combining perfusion defect of CEUS patterns and WBC yielded an area under the receiver operating characteristic curve of 0.831, higher than single 0.720 and 0.774, respectively. The cut-off value of WBC (7.28 × 109/L) helped remaining 65.2% (15/23) atypical cases to be correctly diagnosed as plasma cell mastitis, not misdiagnosed as breast cancer. In conclusion, CEUS presented a clear perfusion defect pattern of plasma cell mastitis lesion for the first time. A precise WBC by routine blood cell analysis test can assist CEUS examination in the differential diagnosis of plasma cell mastitis and breast cancer. It is a promised combination for laboratory diagnostic of PCM.


Assuntos
Neoplasias da Mama , Mastite/sangue , Plasmócitos , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/sangue , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/diagnóstico por imagem , Meios de Contraste , Diagnóstico Diferencial , Feminino , Humanos , Mastite/diagnóstico , Mastite/diagnóstico por imagem , Pessoa de Meia-Idade , Estudos Retrospectivos , Ultrassonografia
6.
J Colloid Interface Sci ; 610: 152-163, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-34922072

RESUMO

The direct catalytic reduction of nitric oxide (NO) by carbon monoxide (CO) to form harmless N2 and CO2 is an ideal strategy to simultaneously remove both these hazardous gases. To investigate the feasibility of using graphitic carbon nitride/titanium dioxide (g-C3N4/TiO2) to catalyze the NO reduction by CO, we systematically explore the effect of the interfacial coupling between g-C3N4 and TiO2 on the photo-induced carrier separation, the light absorption, and the surface reaction for the NO reduction by using density functional theory. The g-C3N4/TiO2 is predicted to have a better photocatalytic activity for NO reduction than g-C3N4, due to the enhanced light absorption intensity and the accelerated separation of the photo-excited electron-hole pairs. By comparing the reaction routes on g-C3N4/TiO2 and g-C3N4, the results indicate that the introduction of TiO2 can keep the surface reaction process intact with the NO dissociation (N2O formation) being the rate-determining (crucial) step. Moreover, TiO2 can facilitate the desorption of NO reduction products, avoiding the deactivation of g-C3N4. This work shows that the composition of TiO2 into g-C3N4 provides a promising catalyst in NO reduction by CO.

7.
J Hazard Mater ; 425: 127756, 2022 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-34883375

RESUMO

The essence behind metal solvent extraction is the interaction between metal species and organic extractants. Aqueous metal species tuning at the molecular level is critical to improve the extraction efficiency and selectivity of the target metal. Herein, we demonstrate a quantitative metal species tuning strategy which is capable of extracting the most critical metals (e.g., V, W, and Mo) in extraction systems constructed by amines. We reveal the superior activities of V4 and V10 species among various V and Cr species by calculations and experiments. In addition, the contribution of various Vn species was quantitatively evaluated via Ion Species Contribution Evaluation (ISCE). Our tuning strategy is rationally designed by bridging species characteristics and routine aqueous conditions with extraction activities. Consequently, a three-dimensional model of V and Cr solvent extraction is established for the prediction of reaction regions, and the reactivities of nearly 20 kinds of typical metal species are compared and predicted. Our strategy serves for industrial solvent extraction, and may provide inspiration for the traditional hydrometallurgical revolutionary.


Assuntos
Vanádio , Água , Íons , Solventes
8.
Front Cell Infect Microbiol ; 11: 724912, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34796124

RESUMO

We previously demonstrated the immunostimulatory efficacy of Pseudomonas aeruginosa flagellar hook protein FlgE on epithelial cells, presumably via ectopic ATP synthases or subunits ATP5B on cell membranes. Here, by using recombinant wild-type FlgE, mutant FlgE (FlgEM; bearing mutations on two postulated critical epitopes B and F), and a FlgE analog in pull-down assay, Western blotting, flow cytometry, and ELISA, actual bindings of FlgE proteins or epitope B/F peptides with ATP5B were all confirmed. Upon treatment with FlgE proteins, human umbilical vein endothelial cells (HUVECs) and SV40-immortalized murine vascular endothelial cells manifested decreased proliferation, migration, tube formation, and surface ATP production and increased apoptosis. FlgE proteins increased the permeability of HUVEC monolayers to soluble large molecules like dextran as well as to neutrophils. Immunofluorescence showed that FlgE induced clustering and conjugation of F-actin in HUVECs. In Balb/c-nude mice bearing transplanted solid tumors, FlgE proteins induced a microvascular hyperpermeability in pinna, lungs, tumor mass, and abdominal cavity. All effects observed in FlgE proteins were partially or completely impaired in FlgEM proteins or blocked by pretreatment with anti-ATP5B antibodies. Upon coculture of bacteria with HUVECs, FlgE was detectable in the membrane and cytosol of HUVECs. It was concluded that FlgE posed a pathogenic ligand of ectopic ATP5B that, upon FlgE-ATP5B coupling on endothelial cells, modulated properties and increased permeability of endothelial layers both in vitro and in vivo. The FlgE-ectopic ATP5B duo might contribute to the pathogenesis of disorders associated with bacterial infection or ectopic ATP5B-positive cells.


Assuntos
Proteínas de Bactérias , Flagelos , Trifosfato de Adenosina , Animais , Proteínas de Bactérias/genética , Células Endoteliais , Camundongos , Camundongos Nus
9.
Eur J Pharm Biopharm ; 160: 143-151, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33524537

RESUMO

Currently, the influences of free terminal groups (hydroxyl, carboxyl and ester) of PLGA on encapsulating active pharmaceutical ingredient are relatively ambiguous even though PLGA types were defined as critical quality attributes in vast majority of design of experiment process. In this study, emulsion method combined with premix membrane emulsification technique has been used to encapsulate ropivacaine (RVC), a small molecule local anesthetic in clinical. Based on the narrow particle size distribution, the influences and mechanisms of the terminal groups on properties of ropivacaine loaded microspheres have been investigated in detail. It was found that microspheres prepared by PLGA with hydroxyl or ester groups exhibited lower encapsulation efficiency but faster in vitro release rate than that of carboxyl groups. In the meanwhile, on microcosmic level analysis by quartz crystal microbalance with dissipation, atomic force microscope and confocal laser scanning microscopy, we attributed this distinction to the specific interaction between ropivacaine and different terminal groups. Subsequently, the reaction activation centers were verified by density functional simulation calculation and frontier molecular orbital theory at molecular level. Additionally, pharmacokinetics and pharmacodynamic research of infiltration anesthesia model were performed to compare sustained release ability, duration and intensity of the anesthetic effect in vivo. Finally, potential safety and toxicity were evaluated by the biochemical analysis. This study not only provides a novel mechanism of drug encapsulation process but also potential flexible selections in terms of various anesthesia indications in clinical.


Assuntos
Anestésicos Locais/administração & dosagem , Portadores de Fármacos/química , Composição de Medicamentos/métodos , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Ropivacaina/administração & dosagem , Anestesia Local/métodos , Anestésicos Locais/efeitos adversos , Anestésicos Locais/farmacocinética , Anestésicos Locais/toxicidade , Animais , Preparações de Ação Retardada/administração & dosagem , Preparações de Ação Retardada/farmacocinética , Liberação Controlada de Fármacos , Emulsões , Injeções Intradérmicas , Masculino , Microesferas , Modelos Animais , Tamanho da Partícula , Ratos , Ropivacaina/efeitos adversos , Ropivacaina/farmacocinética , Ropivacaina/toxicidade , Testes de Toxicidade Aguda
10.
J Hazard Mater ; 404(Pt A): 124153, 2021 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-33059253

RESUMO

We propose a new metal-free scheme of the reaction between the molecules CO and NO on a g-C3N4 monolayer. We first investigate the electronic properties of the related molecules CO, NO, N2, and CO2 adsorbed g-C3N4 systems, and then figure out the possible reaction pathways. It is shown that all the molecules will be physisorbed above the triangular cavity. Also, we find the NO binding on g-C3N4 is stronger than CO. The NO dissociation will be the rate-determining step of the reaction, and the formation of NCO· intermediate will play a critical role for the reaction process. This research presents a new route of applying g-C3N4 as a catalyst in the NO catalytic degradation reaction.

11.
Cell Biosci ; 10: 117, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33062255

RESUMO

N6-methyladenosine (m6A) modification is the most common internal modification of eukaryotic mRNA and is widely involved in many cellular processes, such as RNA transcription, splicing, nuclear transport, degradation, and translation. m6A has been shown to plays important roles in the initiation and progression of various cancers. The altered metabolic programming of cancer cells promotes their cell-autonomous proliferation and survival, leading to an indispensable hallmark of cancers. Accumulating evidence has demonstrated that this epigenetic modification exerts extensive effects on the cancer metabolic network by either directly regulating the expression of metabolic genes or modulating metabolism-associated signaling pathways. In this review, we summarized the regulatory mechanisms and biological functions of m6A and its role in cancer metabolic reprogramming.

12.
Water Res ; 186: 116362, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32916619

RESUMO

As an important raw material and intermediate of widely used antibiotics cefazolin and cefazedone, 2-mecapto-5-methyl-1,3,4-thiadizaole (MMTD) in antibiotic wastewater is hardly decyclized during wastewater treatment, posing great risk to the environment. This work proposed a green "coupling-oxidation" process to enhance ring-opening of MMTD during antibiotic wastewater treatment. In particular, the significant role of humic substances (HS) as pre-coupling reagent was emphasized. Real HS and different model HS, especially quinones, not only efficiently pre-coupled MMTD (>95%) but also promoted the MMTD removal by MnO2 (from 72.4% to 92.4%). Mass spectrometric analysis indicated that MMTD pre-coupled to HS would be oxidized with ring opening to environmental-friendly sulfonated HS, while direct oxidation of MMTD produced MMTD dimers or sulfonated MMTD that would not undergo ring opening. Theoretical calculations indicated that pre-coupling to HS enabled the ring-opening oxidation by increasing the nucleophilicity and decreasing ring-opening barrier of thiadiazole. Based on the density function theory (DFT), the global nucleophilicity index (Nu) followed the trend of HS-MMTD > MMTD dimer > sulfonated MMTD, while the ring-opening barrier followed the trend of HS-MMTD (274 kJ/mol) < first ring of MMTD dimers (286 kJ/mol) < MMTD (338 kJ/mol). Theoretical calculations further confirmed that the cross-coupled HS-MMTD intermediate was more likely to be decyclized than intermediates from direct oxidation. Moreover, nitrogen, acetaldehyde group, sulfate and CO2 were the products of thiadiazole ring degradation. Pre-coupling of MMTD with HS provides a new idea and strategy in developing a green and sustainable scheme for wastewater treatment.


Assuntos
Compostos de Manganês , Águas Residuárias , Substâncias Húmicas , Oxirredução , Óxidos
13.
J Clin Lab Anal ; 34(5): e23191, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31901184

RESUMO

BACKGROUND: The differential diagnoses of patients hospitalized for respiratory infections due to influenza virus vs other pathogens are challenging. Our study investigated whether hematological parameters such as neutrophil (N), lymphocyte (L), platelet (PLT), and neutrophil-to-lymphocyte ratio (NLR) contributed in diagnosing influenza virus infections and in discriminating other respiratory infections. METHODS: We retrospectively analyzed the laboratory characteristics of 307 patients with respiratory infections caused by influenza/non-influenza virus and bacteria. The diagnostic abilities of hematological indexes were evaluated in the patients compared with 100 healthy people. RESULTS: The hematological parameters in patients with influenza virus infection were dramatically altered compared with those in the controls. Additionally, among the systemic inflammatory markers, the sensitivity of NLR for influenza detection was higher than that of N and L. PLT was significantly lower in influenza virus-positive infection than in influenza virus-negative infection. Moreover, when patients with influenza virus infection were cured, PLT returned to a normal level. The red blood cell (RBC) and hemoglobin (Hb) levels of influenza virus infection were higher than those of bacterial infection. Compared with traditional N and L, NLR and platelet-to-neutrophil (PNR) showed greater significance between influenza virus and bacterial infection (P < .01). CONCLUSION: Neutrophil-to-lymphocyte ratio with high sensitivity is a preferable diagnostic tool to screen influenza virus-infected patients than N and L. PLT accounts in the differential diagnoses of respiratory infections due to influenza virus and other pathogens among patients. In addition, RBC, Hb, NLR, and PNR can significantly differentiate between influenza virus infections and bacterial infections.


Assuntos
Contagem de Células Sanguíneas , Influenza Humana/sangue , Influenza Humana/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Infecções Bacterianas/sangue , Infecções Bacterianas/diagnóstico , Feminino , Hospitalização , Humanos , Influenza Humana/etiologia , Masculino , Pessoa de Meia-Idade , Infecções Respiratórias/diagnóstico , Infecções Respiratórias/etiologia , Estudos Retrospectivos , Sensibilidade e Especificidade , Adulto Jovem
14.
RSC Adv ; 10(39): 23491-23497, 2020 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-35520328

RESUMO

The catalytic reduction behaviours between NO and CO on a CaFe2O4 surface were studied using flue gas recirculation. The reaction mechanism and control principle were investigated via experiment and theoretical calculations. The experiment results show that CaFe2O4 can catalyse the reduction of NO by CO, and the NO conversion rate increases with the increase in CO concentration. The theoretical calculations indicate that the CO-NO reaction on CaFe2O4 surfaces complies with the Eley-Rideal mechanism, and the reaction path is controlled by nitrogen, oxygen and isocyanate radicals. Specifically, the dissociation of NO into nitrogen and oxygen radicals, and the formation of subsequent isocyanate radicals dominate the reaction. The results provide new insight into the intrinsic reaction mechanism and the meso-scale control principle, allowing us to propose a novel process design scheme to improve the NO x emission reduction efficiency in the flue gas recirculation process.

15.
J Hazard Mater ; 351: 169-176, 2018 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-29533889

RESUMO

The nitrogen heterocyclic compounds (NHCs) are very toxic and widely used in many industries, while the treatment of NHCs in wastewater has not attracted enough concern till now. Here we studied the complete degradation of a typical NHCs, benzopyrazole (BP), in wet oxidation. The effects of different operation parameters, such as stirring speed, temperature, reaction time and initial pH, on BP degradation and chemical oxygen demand (COD) removal were studied. BP was totally degraded and the COD removal efficiency achieved 76.7%, after 120 min reaction at 220 °C with initial pH 6.5. Meanwhile, 81.7% of the nitrogen from BP was removed from the solution. The toxicity of the BP solution was reduced by 95.2% after wet oxidation at 240 °C for 180 min. The influences of coexisted NO3-, CO32-, SO42- and PO43- ions were also investigated. With quantum chemical calculation and intermediates analysis by electrospray ionization mass spectrometry, a very detailed degradation pathway of BP in wet oxidation was proposed.

16.
Sci Rep ; 7(1): 16877, 2017 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-29203871

RESUMO

Corynebacterium pyruviciproducens (C. pyruviciproducens, CP), as a newly discovered immunomodulator, has been confirmed to have a stronger immunoregulation than Propionibacterium acnes (P. acnes) of the traditional immune adjuvant, by previous experiments with model antigen ovalbumin and sheep red blood cells. Here, it was designed to assess its ability to resist methicillin-resistant Staphylococcus aureus (MRSA), since MRSA as a vital gram positive pathogen is characterized by high morbidity and mortality. In this report, it was indicated that C. pyruviciproducens and its peptidoglycan (CP-PGN) could help to be against bloodstream infection of MRSA with raised survival rate, decreased bacteria load and alleviated systemic inflammation, and these effects of CP-PGN were more pronounced. However, the whole CP was inclined to prevent localized abdominal infection of MRSA from progressing to a systemic infection. And they showed the potential as a therapeutic drug alone or combined with vancomycin. The diversity of capacity of activating macrophages induced by CP and CP-PGN may result in distinct resistance to MRSA in different infection models. Furthermore, both CP and CP-PGN induced M1 macrophages. In conclusion, CP and its PGN could act as promising immune agents to treat and prevent MRSA infection.


Assuntos
Corynebacterium/fisiologia , Macrófagos/imunologia , Peptidoglicano/uso terapêutico , Infecções Estafilocócicas/tratamento farmacológico , Animais , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Citocinas/metabolismo , Modelos Animais de Doenças , Quimioterapia Combinada , Feminino , Estimativa de Kaplan-Meier , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Peptidoglicano/farmacologia , Fagocitose , Células RAW 264.7 , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Infecções Estafilocócicas/imunologia , Infecções Estafilocócicas/microbiologia , Infecções Estafilocócicas/mortalidade , Receptor 2 Toll-Like/antagonistas & inibidores , Receptor 2 Toll-Like/genética , Receptor 2 Toll-Like/metabolismo , Vancomicina/farmacologia , Vancomicina/uso terapêutico
17.
Environ Sci Technol ; 51(22): 13380-13387, 2017 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-29064241

RESUMO

Reactive oxygen species (ROS) are key oxidants for the degradation of organic pollutants in sunlight-driven photocatalytic water treatment, but their interaction with the photocatalyst is easily ignored and, hence, is comparatively poorly understood. Here we show that graphitic carbon nitride (C3N4, a famous visible-light-responsive photocatalyst) is chemically stable toward ozone and superoxide radical; in contrast, hydroxyl radical (•OH) can tear the heptazine unit directly from C3N4 to form cyameluric acid and further release nitrates into the aqueous environment. The ratios of released nitrogen from nanosheet-structured C3N4 and bulk C3N4 that finally exists in the form of NO3- reach 9.5 and 6.8 mol % in initially ultrapure water, respectively, after 10 h treatment by solar photocatalytic ozonation, which can rapidly generate abundant •OH to attack C3N4. On a positive note, in the presence of organic pollutants which compete against C3N4 for •OH, the C3N4 decomposition has been completely or partially blocked; therefore, the stability of C3N4 under practical working conditions has been obviously preserved. This work supplements the missing knowledge of the chemical instability of C3N4 toward •OH and calls for attention to the potential deactivation and secondary pollution of catalysts in •OH-involved water treatment processes.


Assuntos
Espécies Reativas de Oxigênio , Luz Solar , Purificação da Água , Catálise , Grafite
18.
Sci Rep ; 7: 42643, 2017 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-28350005

RESUMO

Carbon-based metal-free catalyst has attracted more and more attention. It is a big challenge to improve catalytic activity of metal-free catalyst for decomposition of H2O2 to produce hydroxyl radical (HO•). Here, we report chloro-benquinone (TCBQ) modified on graphene oxide (GO) as metal-free catalyst for strong promotion of HO•. By the incorporation of GO, the HO• production by H2O2 and TCBQ is significantly promoted. Based on density functional theory, TCBQ modified GO (GO-TCBQ) is more prone to be nucleophilic attacked by H2O2 to yield HO• via electron transfer acceleration. Furthermore, the generated HO• can cut GO nanosheets into uniform ultra-small graphene oxide (USGO) through the cleavage of epoxy and C-C bonds. Interestingly, the damaged GO and in situ formed GO fragments can further enhance decomposition of H2O2 to produce HO•. Different from other catalytic processes, the GO-TCBQ metal-free catalysis process can be enhanced by GO itself, producing more HO•, and uniform USGO also can be generated. Thus, the metal free catalysis will be considered a fabrication method for uniform USGO, and may be extended to other fields including detoxifying organic pollutants and the application as disinfectants.

19.
J Hazard Mater ; 304: 126-33, 2016 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-26547621

RESUMO

A comparative study was constructed to correlate the electronic property of the substituents with the degradation rates of phenolic compounds and their oxidation pathways under UV with Ag(+)/TiO2 suspensions. It was verified that a weak electron withdrawing substituent benefited photocatalytic oxidation the most, while an adverse impact appeared when a substituent was present with stronger electron donating or withdrawing ability. The addition of p-benzoquinone dramatically blocked the degradation, confirming superoxide radicals (O2(-)) as the dominant photooxidant, rather than hydroxyl radicals, singlet oxygen or positive holes, which was also independent of the substituent. Hammett relationship was established based on pseudo-first-order reaction kinetics, and it revealed two disparate reaction patterns between O2(-) and phenolic compounds, which was further verified by the quantum chemical computation on the frontier molecular orbitals and Mulliken charge distributions of O2(-) and phenolic compounds. It was found that electron donating group (EDG) substituted phenols were more likely nucleophilically attacked by O2(-), while O2(-) preferred to electrophilically assault electron withdrawing group (EWG) substituted phenols. Exceptionally, electrophilic and nucleophilic attack by O2(-) could simultaneously occur in p-chlorophenol degradation, consequently leading to its highest rate constant. Possible reactive positions on the phenolic compounds were also detailedly uncovered.

20.
J Clin Diagn Res ; 9(7): DC01-4, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26393125

RESUMO

OBJECTIVES: The present study was aimed to investigate the antibiotic resistance, virulence potential and phylogenetic grouping of ESBL-producing uropathogenic Escherichia coli (EP-UPEC) isolated from long-term hospitalized patients. MATERIALS AND METHODS: EP-UPEC isolates from September 2013 to June 2014 at a tertiary care hospital of China were screened for ESBL-production by the double disk diffusion test. Isolates with ESBL-phenotype were further characterized by antibiotic resistance testing, PCR of different ESBL and virulence genes, and phylogenetic grouping. RESULTS: One hundred and twenty EP-UPEC were isolated from long-term hospitalized patients. All EP-UPEC isolates were resistant to Ampicillin, Cefazolin, Cefuroxime, Cefotaxime, Cefoperazone and Ceftriaxone, and the majority of EP-UPEC isolates were resistant to Piperacillin (82.5%), Ciprofloxacin (81.2%), Trimethoprim-Sulfamethoxazole (72.5%). The isolates showed the highest sensitivity against Imipenem (98.4%), Piperacillin/tazobactam (96.7%), Cefoperazone/sulbactam (91.7%), Amikacin (90.8%) and Cefepime (75.8%). Nine different ESBL genotype patterns were observed and CTX-M type was the most prevalent ESBL genotype (42.5%, 51/120). Majority of EP-UPEC isolates possess more than one ESBL genes. EP-UPEC isolates belonged mainly to phylogenetic group B2(36.7%) and D(35.0%). The prevalence of traT, ompT, iss, PAI, afa, fimH and papC were 75.8%, 63.3%, 63.3%, 60.8%, 40.8%, 19.2% and 6.7%, respectively. The number of virulence genes (VGs) detected was significantly higher in group B2 than in group A (ANOVA, p<0.001), group B1(ANOVA, p= 0.012) and D (ANOVA, p<0.001). CONCLUSIONS: EP-UPEC strains showed multidrug resistance and co-resistance to other non ß-lactam antibiotics. CTX-M was the most prevalent ESBL genotype and majority of EP-UPEC strains more than one ESBL genes. EP-UPEC strains belonged mainly to phylogenetic group B2 and D, and most of the virulence genes were more prevalent in group B2.

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