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1.
Antimicrob Agents Chemother ; : e0034424, 2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-39194261

RESUMO

Limited treatment options and multidrug-resistant (MDR) Klebsiella pneumoniae present a significant therapeutic challenge, underscoring the need for novel approaches. Drug repurposing is a promising tool for augmenting the activity of many antibiotics. This study aimed to identify novel synergistic drug combinations against K. pneumoniae based on drug repurposing. We used the clinically isolated GN 172867 MDR strain of K. pneumoniae to determine the reversal resistance activity of zidovudine (AZT). The combined effects of AZT and various antibiotics, including nitrofurantoin (NIT) and omadacycline (OMC), were examined using the checkerboard method, growth curves, and crystal violet assays to assess biofilms. An in vitro combination activity testing was carried out in 12 isolates of K. pneumoniae. In vivo murine urinary tract and lung infection models were used to evaluate the therapeutic effects of AZT + NIT and AZT + OMC, respectively. The fractional inhibitory concentration index and growth curve demonstrated that AZT synergized with NIT or OMC against K. pneumoniae strains. In addition, AZT + NIT inhibited biofilm formation and cleared mature biofilms. In vivo, compared with untreated GN 172867-infected mice, AZT + NIT and AZT + OMC treatment decreased colony counts in multiple tissues (P < 0.05) and pathological scores in the bladder and kidneys (P < 0.05) and increased the survival rate by 60% (P < 0.05). This study evaluated the combination of AZT and antibiotics to treat drug-resistant K. pneumoniae infections and found novel drug combinations for the treatment of acute urinary tract infections. These findings suggest that AZT may exert significant anti-resistance activity.

2.
Microbiol Spectr ; : e0012224, 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39150249

RESUMO

Background emergence of multidrug-resistant (MDR) bacterial strains is a public health concern that threatens global and regional security. Efflux pump-overexpressing MDR strains from clinical isolates are the best subjects for studying the mechanisms of MDR caused by bacterial efflux pumps. A Klebsiella pneumoniae strain overexpressing the OqxB-only efflux pump was screened from a clinical strain library to explore reverse OqxB-mediated bacterial resistance strategies. We identified non-repetitive clinical isolated K. pneumoniae strains using a matrix-assisted laser desorption/ionization time-of-flight (TOF) mass spectrometry clinical TOF-II (Clin-TOF-II) and susceptibility test screening against levofloxacin and ciprofloxacin. And the polymorphism analysis was conducted using pulsed-field gel electrophoresis. Efflux pump function of resistant strains is obtained by combined drug sensitivity test of phenylalanine-arginine beta-naphthylamide (PaßN, an efflux pump inhibitor) and detection with ethidium bromide as an indicator. The quantitative reverse transcription PCR was performed to assess whether the oqxB gene was overexpressed in K. pneumoniae isolates. Additional analyses assessed whether the oqxB gene was overexpressed in K. pneumoniae isolates and gene knockout and complementation strains were constructed. The binding mode of PaßN with OqxB was determined using molecular docking modeling. Among the clinical quinolone-resistant K. pneumoniae strains, one mediates resistance almost exclusively through the overexpression of the resistance-nodulation-division efflux pump, OqxB. Crystal structure of OqxB has been reported recently by N. Bharatham, P. Bhowmik, M. Aoki, U. Okada et al. (Nat Commun 12:5400, 2021, https://doi.org/10.1038/s41467-021-25679-0). The discovery of this strain will contribute to a better understanding of the role of the OqxB transporter in K. pneumoniae and builds on the foundation for addressing the threat posed by quinolone resistance.IMPORTANCEThe emergence of antimicrobial resistance is a growing and significant health concern, particularly in the context of K. pneumoniae infections. The upregulation of efflux pump systems is a key factor that contributes to this resistance. Our results indicated that the K. pneumoniae strain GN 172867 exhibited a higher oqxB gene expression compared to the reference strain ATCC 43816. Deletion of oqxB led a decrease in the minimum inhibitory concentration of levofloxacin. Complementation with oqxB rescued antibiotic resistance in the oqxB mutant strain. We demonstrated that the overexpression of the OqxB efflux pump plays an important role in quinolone resistance. The discovery of strain GN 172867 will contribute to a better understanding of the role of the OqxB transporter in K. pneumoniae and promotes further study of antimicrobial resistance.

4.
Microbiol Spectr ; 11(4): e0033423, 2023 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-37272820

RESUMO

Klebsiella pneumoniae, a pathogen of critical clinical concern, urgently demands effective therapeutic options owing to its drug resistance. Polymyxins are increasingly regarded as a last-line therapeutic option for the treatment of multidrug-resistant (MDR) Gram-negative bacterial infections. However, polymyxin resistance in K. pneumoniae is an emerging issue. Here, we report that gallium nitrate (GaNt), an antimicrobial candidate, exhibits a potentiating effect on colistin against MDR K. pneumoniae clinical isolates. To further confirm this, we investigated the efficacy of combined GaNt and colistin in vitro using spot dilution and rapid time-kill assays and growth curve inhibition tests and in vivo using a murine lung infection model. The results showed that GaNt significantly increased the antimicrobial activity of colistin, especially in the iron-limiting media. Mechanistic studies demonstrated that bacterial antioxidant activity was repressed by GaNt, as revealed by RNA sequencing (RNA-seq), leading to intracellular accumulation of reactive oxygen species (ROS) in K. pneumoniae, which was enhanced in the presence of colistin. Therefore, oxidative stress induced by GaNt and colistin augments the colistin-mediated killing of wild-type cells, which can be abolished by dimethyl sulfoxide (DMSO), an effective ROS scavenger. Collectively, our study indicates that GaNt has a notable impact on the antimicrobial activity of colistin against K. pneumoniae, revealing the potential of GaNt as a novel colistin adjuvant to improve the treatment outcomes of bacterial infections. IMPORTANCE This study aimed to determine the antimicrobial activity of GaNt combined with colistin against Klebsiella pneumoniae in vitro and in vivo. Our results suggest that by combining GaNt with colistin, antioxidant activity was suppressed and reactive oxygen species accumulation was induced in bacterial cells, enhancing antimicrobial activity against K. pneumoniae. We found that GaNt functioned as an antibiotic adjuvant when combined with colistin by inhibiting the growth of multidrug-resistant K. pneumoniae. Our study provides insight into the use of an adjuvant to boost the antibiotic potential of colistin for treating infections caused by multidrug-resistant K. pneumoniae.


Assuntos
Anti-Infecciosos , Infecções por Klebsiella , Camundongos , Animais , Colistina/farmacologia , Klebsiella pneumoniae/genética , Espécies Reativas de Oxigênio , Antioxidantes/farmacologia , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Anti-Infecciosos/farmacologia , Polimixinas/farmacologia , Polimixinas/uso terapêutico , Testes de Sensibilidade Microbiana , Infecções por Klebsiella/tratamento farmacológico , Infecções por Klebsiella/microbiologia , Farmacorresistência Bacteriana Múltipla
5.
J Stroke Cerebrovasc Dis ; 32(2): 106949, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36535134

RESUMO

OBJECTIVE: Ischaemic stroke has a high death rate and frequently results in long-term and severe brain damage in survivors. miRNA-124-3p (miR-124-3p) treatment has been suggested to reduce ischaemia and play a vital function in avoiding neuron death. An investigation of the role of miR-124-3p, in the ischaemia damage repair or protection in the middle cerebral artery occlusion (MCAO) model and oxygen-glucose deprivation/reperfusion (OGD/R) model, was the purpose of this research. METHODS: The expression of miRNA and mRNA in the MCAO model was predicted using bioinformatics analysis. The OGD/R neuronal model was developed. We examined the influence of a number of compounds on the OGD/R model in vitro using gain- and loss-of-function approaches. RESULTS: For starters, miR-124-3p and Nrep level in the MCAO model were found to be lower in the model predicted by bioinformatics than in the sham-operated group. And then in the OGD/R model, miR-124-3p treatment reduced OGD/R neuronal damage, increased neuronal survival, and reduced apoptosis in cell lines. Moreover, we further looked at the impact of miR-124-3p on downstream Rnf38 and Nrep using the OGD/R model. Western blot analysis and dual-luciferase reporter assays indicated that miR-124-3p binds and inhibits Rnf38. Finally, although Nrep expression was reduced in the OGD/R model neuronal model, it was shown that miR-124-3p administration reduced apoptosis and increased neuronal activity, particularly with regard to axon regeneration-related proteins. CONCLUSION: Our studies have shown that miR-124-3p may reduce neuronal injury by preventing Rnf38-mediated effects on the Nrep axis.


Assuntos
Lesões Encefálicas , Isquemia Encefálica , MicroRNAs , Traumatismo por Reperfusão , Acidente Vascular Cerebral , Apoptose , Axônios/metabolismo , Isquemia Encefálica/genética , Isquemia Encefálica/terapia , Isquemia Encefálica/metabolismo , Glucose , Infarto da Artéria Cerebral Média/genética , Infarto da Artéria Cerebral Média/terapia , Infarto da Artéria Cerebral Média/metabolismo , MicroRNAs/metabolismo , Regeneração Nervosa , Oxigênio , Traumatismo por Reperfusão/genética , Traumatismo por Reperfusão/prevenção & controle , Traumatismo por Reperfusão/metabolismo , Ubiquitina-Proteína Ligases , Animais , Camundongos
6.
Infect Drug Resist ; 15: 7537-7553, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36575674

RESUMO

Purpose: To analyze the differences in clinical distribution and antimicrobial resistance of pathogens among northern Anhui, central Anhui, and southern Anhui in 2021, and to provide a basis for the rational use of drugs for clinicians in different regions. Methods: Nonrepetitive pathogens isolated from clinical samples of inpatients and outpatients from 59 member units with qualified data in 2021 were obtained from the Anhui Province Antimicrobial Resistance Surveillance System, which was divided into northern Anhui, central Anhui, and southern Anhui by region. Identification and antimicrobial susceptibility analyses were carried out using the Vitek 2 Compact and standard disc diffusion method. The results were determined according to the American Clinical Laboratory Standards Institute in 2021 with data analyzed using WHONET 5.6 and SPSS 17.0. Results: A total of 133,268 pathogenic bacteria were isolated from clinical samples. Staphylococcus aureus (S. aureus) was the most common gram-positive bacterium and Escherichia coli (E. coli) was the most common gram-negative bacterium. Sputum was the main source of clinical specimens. The detection rates of methicillin-resistant S.aureus, methicillin-resistant coagulase-negative Staphylococcus, carbapenem-resistant E. coli, carbapenem-resistant Klebsiella pneumoniae (K. pneumoniae), carbapenem-resistant Acinetobacter baumannii, third-generation cephalosporin-resistant E. coli, and third-generation cephalosporin-resistant K. pneumoniae were higher in northern Anhui than in southern Anhui (P<0.0001). E. coli, K. pneumoniae, and Pseudomonas aeruginosa were sensitive to amikacin. Strains resistant to vancomycin, linezolid, and teicoplanin were not isolated until 2021. Conclusion: There were significant differences in bacterial resistance in different regions of Anhui Province. Antibiotic resistance in northern Anhui was the most serious in 2021. Antimicrobial agents must be used according to the resistance of the bacteria in the local region.

7.
Int Urol Nephrol ; 53(10): 1987-1993, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34227015

RESUMO

BACKGROUND: Ureteroscopy is widely applied in pregnant women with renal colic, but such patients are easy to experience uterine contraction after surgery. There are many factors which may affect uterine contraction, this study aims to explore the risk factors of uterine contraction triggered by ureteroscopy in pregnant women with renal colic. METHODS: One hundred and one pregnant women were retrospectively analyzed, the patients were hospitalized because of severe renal colic. All patients received ureteroscopy during which double J catheters were inserted into ureters for drainage. Patients received other medical treatments individually according to their condition and uterine contractions were detected by EHG within 12 h after operation. Patients were classified as group A (uterine contraction) and group B (no uterine contraction) according to the presence or absence of continuously regular uterine contraction. Clinical characteristics were collected for further analysis, including history of childbirth, anesthesia method, application of phloroglucinol or not, operation time, Oxygen inhalation or not, pain relief or not after surgery, systemic inflammatory response syndrome (SIRS) occurred or not. A binary logistic regression analysis model was established to explore whether such clinical characteristics were relevant to uterine contraction after ureteroscopy. RESULTS: Continuously regular uterine contraction presented in 46 pregnant women within 12 h after ureteroscopy, making the incidence of uterine contraction as high as 45.54%. The presence of uterine contraction was related to the following factors(P < 0.05): history of childbirth (primipara versus multipara)(OR 6.593, 95% CI 2.231-19.490), operation time (each quarter additional) (OR 2.385, 95% CI 1.342-4.238), application of phloroglucinol (yes versus not) (OR 6.959, 95% CI 1.416-34.194), pain relief after surgery(yes versus not)(OR 6.707, 95% CI 1.978-22.738), SIRS occurred after surgery (yes versus not) (OR 0.099, 95% CI 0.014-0.713). CONCLUSION: Continuously regular uterine contraction is easy to occur within 12 h after ureteroscopy in pregnant women. SIRS occurred after surgery is a risk factor for uterine contraction; on the contrary, no history of childbirth, shorter operation time, application of phloroglucinol, pain relief after surgery are protective factors.


Assuntos
Complicações na Gravidez/diagnóstico , Cólica Renal/diagnóstico , Ureteroscopia/efeitos adversos , Contração Uterina , Adulto , Feminino , Humanos , Gravidez , Estudos Retrospectivos , Fatores de Risco , Adulto Jovem
8.
Front Mol Biosci ; 8: 638995, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33855047

RESUMO

CRISPR-CasRx technology provides a new and powerful method for studying cellular RNA in human cancer. Herein, the pattern of expression of long noncoding RNA 00341 (LINC00341) as well as its biological function in bladder cancer were studied using CRISPR-CasRx. qRT-PCR was employed to quantify the levels of expression of LINC00341 in tumor tissues along with the matched non-tumor tissues. sgRNA targeting LINC00341 or the sgRNA negative control were transiently transfected into the T24 as well as 5,637 human bladder cancer cell lines. CCK-8, ELISA as well as wound healing methods were employed to explore cell proliferation, apoptosis and migration, respectively. The tumorigenicity experiment in nude mice also performed to detect cell proliferation. The expression of p21, Bax as well as E-cadherin were assayed using western blot. The results demonstrated that LINC00341 was overexpressed in bladder cancer in contrast with the healthy tissues. The LINC00341 expression level in high-grade tumors was higher in contrast with that in low-grade tumors. The expression of linc00341 was higher relative to that of non-invasive tumors. In T24 as well as 5637-cell lines harboring LINC00341-sgRNA, inhibition of cell proliferation (in vitro and in vivo), elevated apoptosis rate and diminished migration ability. Moreover, silencing LINC00341 upregulated the expressions of p21, Bax as well as E-cadherin. Knockout of these genes could eliminate the phenotypic changes caused by sgRNA targeting LINC00341. Our data demonstrate that LINC00341 has a carcinogenic role in human bladder cancer.

9.
Front Mol Biosci ; 8: 657145, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33859998

RESUMO

Recent research evidence documents that lncRNAs (long non-coding RNAs lncRNAs) play a pivotal role in the tumorigenesis and development of tumors. LncRNA SNGH3 (small nucleolar RNA host gene 3) is highly expressed in numerous forms of cancer, serving as an oncogene in cancer progression. Nonetheless, the clinical relationship, along with the mechanism of SNGH3 in bladder cancer, have not been studied. Herein, the findings exhibited upregulation of SNGH3 in bladder cancer tissues, along with the cell lines. Furthermore, overexpressed SNGH3 was positively linked to the TNM stage, as well as the histological grade of bladder cancer. Moreover, the silencing of SNGH3, using CRISPR-dCas9, suppressed cell growth along with migration, but elevated bladder cancer cell apoptosis. In summary, we established that SNGH3 serves as a bladder cancer oncogene and could be employed as a prospective diagnostic marker for clinical use, and is also a therapeutic target for CRISPR-mediated gene therapy.

10.
Int J Biol Sci ; 16(13): 2271-2282, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32760196

RESUMO

Insulin-like growth factor binding protein 4-1 (IGFBP4-1), a new long noncoding RNA (lncRNA), has been reported to contribute to tumorigenesis and has been suggested to be a poor prognostic marker in human lung cancer. However, there still lacks basic studies that investigated the biological role of IGFBP4-1 in bladder urothelial carcinoma to date. In this study, we investigated the relationship between IGFBP4-1 expression and prognosis in patients with bladder cancer. Cell proliferation, cell cycle and cell apoptosis assays were performed to assess IGFBP4-1 function by up-regulating or down-regulating IGFBP4-1 in bladder cancer cells. A xenograft mice model was used to validate the in vitro results. Blockade of Janus kinase-signal transducer and activator of transcription pathway (JAK/STAT) was used to evaluate JAK/STAT signaling activity. The results showed that IGFBP4-1 was overexpressed in bladder cancer tissues compared with that in normal bladder tissues, and its expression level was positively correlated with poor prognosis in bladder cancer patients. Overexpression of IGFBP4-1 markedly promoted cell proliferation and cell cycle progression, and inhibited cell apoptosis, while knockdown of IGFBP4-1 notably suppressed the proliferation, promoted cell apoptosis, and induced cell cycle arrest at the G0/G1 phase. Mechanistically, we revealed that IGFBP4-1 promotes the activation of the JAK/STAT pathway in bladder cancer cells. Moreover, the JAK/STAT inhibitor dramatically blocked the tumor-promoting activity of IGFBP4-1. Tumor growth in vivo was also suppressed by knocking down of IGFBP4-1. In conclusion, IGFBP4-1 promoted bladder cancer progression by activating the JAK/STAT signaling pathway. These findings suggest that IGFBP4-1 exhibits an oncogenic role in the development of human bladder cancer.


Assuntos
Carcinoma/metabolismo , Proteína 4 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Janus Quinases/metabolismo , Fatores de Transcrição STAT/metabolismo , Neoplasias da Bexiga Urinária/metabolismo , Animais , Apoptose , Carcinoma/genética , Ciclo Celular , Linhagem Celular Tumoral , Proliferação de Células , Bases de Dados Genéticas , Regulação para Baixo , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Proteína 4 de Ligação a Fator de Crescimento Semelhante à Insulina/genética , Janus Quinases/genética , Masculino , Camundongos , Camundongos Nus , Pessoa de Meia-Idade , Neoplasias Experimentais , RNA Longo não Codificante , Fatores de Transcrição STAT/genética , Regulação para Cima , Neoplasias da Bexiga Urinária/genética
11.
Exp Ther Med ; 19(6): 3856-3860, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32346451

RESUMO

The long-lasting infection of high-risk type (type 16 or type 18) human papillomavirus (HPV) is the main cause of gynecological and urinary malignancies. Given the high mortality rate after surgery, the development of a new molecular therapy would be of value to clinicians. The aim of the present study was to achieve targeted inactivation of the viral E6 gene in keratinocytes using the reprogrammed CRISPR-Cas13a system. To accomplish this, a reprogrammed CRISPR-Cas13a system, targeting both the HPV16/18 E6 genes was constructed using a guide RNA expressing vector. The expression levels of E6 protein were measured using western blot analysis after transfection of the vector into E6-transformed keratin oocytes. Cell proliferation was analyzed using CCK-8 assays and cell apoptosis was evaluated using Hoechst 33258 staining and ELISAs examining caspase-3 levels. The results indicated that both the HPV16/18 E6 genes can be inactivated using the CRISPR-Cas13a system. Furthermore, silencing E6 inhibited cell proliferation (14±1.8% on average) and induced apoptosis (80.2±3.2% on average) in E6-transformed keratinocytes but not in normal keratinocytes. In conclusion, results of the present study demonstrate that the reprogrammed CRISPR-Cas13a system has the potential for inactivating HPV E6 gene functions.

12.
Yao Xue Xue Bao ; 42(2): 118-26, 2007 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-17518037

RESUMO

Homoisoflavonoid is a special type in flavonoids. There are more than 110 homoisoflavonoid compounds isolated from natural materials. Homoisoflavonoid compounds show many bioactivities on anti-inflammatory, estrogenicy, antiestrogenic, anticancer and angioprotective etc. This paper summarized the plant sources, structural types spectrocopy features and the biology activities of homoisoflavonoids.


Assuntos
Anti-Inflamatórios/farmacologia , Antimutagênicos/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Isoflavonas/química , Isoflavonas/isolamento & purificação , Plantas Medicinais/química , Animais , Humanos , Isoflavonas/farmacologia , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Vasodilatadores/farmacologia
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