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1.
World J Microbiol Biotechnol ; 40(8): 233, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38842631

RESUMO

Tigecycline-non-susceptible Klebsiella pneumoniae (TNSKP) is increasing and has emerged as a global public health issue. However, the mechanism of tigecycline resistance remains unclear. The objective of this study was to investigate the potential role of efflux pump system in tigecycline resistance. 29 tigecycline-non-susceptible Klebsiella pneumoniae (TNSKP) strains were collected and their minimum inhibitory concentrations (MIC) were determined by the broth microdilution method. The ramR, acrR, rpsJ, tet(A), and tet(X) were amplified by polymerase chain reaction (PCR). The mRNA expression of different efflux pump genes and regulator genes were analyzed by real-time PCR. Additionally, KP14 was selected for genome sequencing. KP14 genes without acrB, oqxB, and TetA were modified using suicide plasmids and MIC of tigecycline of KP14 with target genes knocked out was investigated. It was found that MIC of tigecycline of 20 out of the 29 TNSKP strains decreased by over four folds once combined with phenyl-arginine-ß-naphthylamide dihydrochloride (PaßN). Most strains exhibited upregulation of AcrAB and oqxAB efflux pumps. The strains with acrB, oqxB, and tetA genes knocked out were constructed, wherein the MIC of tigecycline of KP14∆acrB and KP14∆tetA was observed to be 2 µg/mL (decreased by 16 folds), the MIC of tigecycline of KP14ΔacrBΔTetA was 0.25 µg/mL (decreased by 128 folds), but the MIC of tigecycline of KP14∆oqxB remained unchanged at 32 µg/mL. The majority of TNSKP strains demonstrated increased expression of AcrAB-TolC and oqxAB, while certain strains showed mutations in other genes associated with tigecycline resistance. In KP14, both overexpression of AcrAB-TolC and tet(A) gene mutation contributed to the mechanism of tigecycline resistance.


Assuntos
Antibacterianos , Proteínas de Bactérias , Klebsiella pneumoniae , Testes de Sensibilidade Microbiana , Mutação , Tigeciclina , Tigeciclina/farmacologia , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/metabolismo , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Regulação Bacteriana da Expressão Gênica , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/metabolismo , Farmacorresistência Bacteriana/genética , Humanos , Antiporters
2.
Infect Drug Resist ; 17: 1599-1614, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38699075

RESUMO

Introduction: As the last line of defense for clinical treatment, Carbapenem antibiotics are increasingly challenged by multi-drug resistant bacteria containing carbapenemases. The rapid spread of these multidrug-resistant bacteria is the greatest threat to severe global health problems. Methods: To solve the problem of rapid transmission of this multidrug-resistant bacteria, we have developed a rapid detection technology using CRPSPR-Cas12a gene editing based on multiple Recombinase polymerase amplification. This technical method can directly isolate the genes of carbapenemase-containing bacteria from samples, with a relatively short detection time of 30 minutes. The instrument used for the detection is relatively inexpensive. Only a water bath can complete the entire experiment of Recombinase polymerase amplification and trans cleavage. This reaction requires no lid during the entire process while reducing a large amount of aerosol pollution. Results: The detection sensitivity of this method is 1.5 CFU/mL, and the specificity is 100%. Discussion: This multi-scene detection method is suitable for screening populations in wild low-resource environments and large-scale indoor crowds. It can be widely used in hospital infection control and prevention and to provide theoretical insights for clinical diagnosis and treatment.

3.
Pol J Microbiol ; 73(1): 89-97, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38437462

RESUMO

Norovirus is highly infectious and rapidly transmissible and represents a major pathogen of sporadic cases and outbreaks of acute gastroenteritis worldwide, causing a substantial disease burden. Recent years have witnessed a dramatic increase in norovirus outbreaks in China, significantly higher than in previous years, among which GII norovirus is the predominant prevalent strain. Therefore, rapid norovirus diagnosis is critical for clinical treatment and transmission control. Hence, we developed a molecular assay based on RPA combined with the CRISPER-CAS12a technique targeting the conserved region of the GII norovirus genome, the results of which could be displayed by fluorescence curves and immunochromatographic lateral-flow test strips. The reaction only required approximately 50 min, and the results were visible by the naked eye with a sensitivity reaching 102 copies/µl. Also, our method does not cross-react with other common pathogens that cause intestinal diarrhea. Furthermore, this assay was easy to perform and inexpensive, which could be widely applied for detecting norovirus in settings including medical institutions at all levels, particularly township health centers in low-resource areas.


Assuntos
Sistemas CRISPR-Cas , Norovirus , Humanos , China , Diarreia/diagnóstico , Surtos de Doenças , Norovirus/genética
4.
World J Microbiol Biotechnol ; 40(4): 116, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38418617

RESUMO

In this study, we devised a diagnostic platform harnessing a combination of recombinase polymerase amplification (RPA) and the clustered regularly interspaced short palindromic repeats (CRISPR)/Cas12a system. Notably, this platform obviates the need for intricate equipment and finds utility in diverse settings. Two result display methods were incorporated in this investigation: the RPA-Cas12a-fluorescence method and the RPA-Cas12a-LFS (lateral flow strip). Upon validation, both display platforms exhibited no instances of cross-reactivity, with seven additional types of fungal pathogens responsible for respiratory infections. The established detection limit was ascertained to be as low as 102 copies/µL. In comparison to fluorescence quantitative PCR, the platform demonstrated a sensitivity of 96.7%, a specificity of 100%, and a consistency rate of 98.0%.This platform provides expeditious, precise, and on-site detection capabilities, thereby rendering it a pivotal diagnostic instrument amenable for deployment in primary healthcare facilities and point-of-care settings.


Assuntos
Pneumonia , Recombinases , Aspergillus fumigatus/genética , Sistemas CRISPR-Cas , Coloração e Rotulagem
5.
Biochem Genet ; 62(1): 1-17, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37266876

RESUMO

Hepatocellular carcinoma (HCC) is one of the leading cause of cancer-associated death in the world. However, due to the complexity of HCC, it is urgent for us to find a reliable and accurate biomarker for HCC gene therapy.TopBP1-interacting checkpoint and replication regulator (TICRR), known as Treslin in vertebrate and sld3 in yeast, is involved in the tumorigenesis, progression, matastasis, diagnosis, and predicting prognosis of HCC. Disappointingly, the mechanism of TICRR expression in HCC is still not described in detail and requires further analysis. In this study, TCGA ( www.tcga-data.nci.nih.gov/tcga/ ) datasets and GEO ( www.ncbi.nlm.nih.gov/geo ) datasets were used to analyze the expression of TICRR in HCC, the relevance of TICRR mRNA expression and clinicopathological characteristics in patients with HCC, and the relationship between TICRR expression and immune infiltration level in Patients with HCC. Based on MethSurv database, the impact of TICRR in patients with HCC was investigated. In addition, GO/KEGG enrichment analysis of TICRR co-expression was performed using the R package. TICRR was found drastically highly expressed in a variety of cancer types including HCC.ROC curve analysis showed that TICRR had higher accuracy in predicting HCC compared with AFP. The expression level of TICRR was marked positively correlated with tumor stage and prognosis in Patients with HCC.GO/KEGG enrichment analysis showed that TICRR was associated with cell division and cell cycle as well as p53 signaling pathway. In addition, patients with high TICRR methylation of cg05841809, cg09403165, and cg03312532 CpG sites were significantly correlated with poor prognosis of HCC. This study demonstrated that increased TICRR expression in HCC might play an important role in the tumorigenesis, progression, diagnosis, and predicting prognosis of HCC. Therefore, TICRR might be used as a promising diagnostic and prognostic biomarker for HCC gene therapy.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , Carcinogênese , Biologia Computacional , Biomarcadores , Proteínas de Ciclo Celular
6.
Infect Drug Resist ; 16: 7271-7288, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38023412

RESUMO

Background: In recent years, carbapenem-resistant Pseudomonas aeruginosa (CRPA) has spread around the world, leading to a high mortality and close attention of medical community. In this study, we aim to find a new strategy of treatment for CRPA infections. Methods: Eight strains of CRPA were collected, and PCR detected the multi-locus sequence typing (MLST). The antimicrobial susceptibility test was conducted using the VITEK@2 compact system. The minimum inhibitory concentration (MIC) for AS101 and mefloquine was determined using the broth dilution method. Antibacterial activity was tested in vitro and in vivo through the chessboard assay, time killing assay, and a mouse model. The mechanism of AS101 combined with mefloquine against CRPA was assessed through the biofilm formation inhibition assay, electron microscopy, and detection of reactive oxygen species (ROS). Results: The results demonstrated that all tested CRPA strains exhibited multidrug resistance. Moreover, our investigation revealed a substantial synergistic antibacterial effect of AS101-mefloquine in vitro. The assay for inhibiting biofilm formation indicated that AS101-mefloquine effectively suppressed the biofilm formation of CRPA-5 and CRPA-6. Furthermore, AS101-mefloquine were observed to disrupt the bacterial cell wall and enhance the permeability of the cell membrane. This effect was achieved by stimulating the production of ROS, which in turn hindered the growth of CRPA-3. To evaluate the therapeutic potential, a murine model of CRPA-3 peritoneal infection was established. Notably, AS101-mefloquine administration resulted in a significant reduction in bacterial load within the liver, kidney, and spleen of mice after 72 hours of treatment. Conclusion: The present study showed that the combination of AS101 and mefloquine yielded a notable synergistic bacteriostatic effect both in vitro and in vivo, suggesting a potential clinical application of this combination in the treatment of CRPA.

7.
J Med Virol ; 95(9): e29090, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37695079

RESUMO

The widespread dissemination of coronavirus 2019 imposes a significant burden on society. Therefore, rapid detection facilitates the reduction of transmission risk. In this study, we proposed a multiplex diagnostic platform for the rapid, ultrasensitive, visual, and simultaneous detection of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) open reading frame 1ab (ORF1ab) and N genes. A visual diagnostic method was developed using a clustered regularly interspaced short palindromic repeat (CRISPR)-Cas12a/Cas13a dual-enzyme digestion system integrated with multiplex reverse transcriptase-recombinase polymerase amplification (RT-RPA). Two CRISPR-Cas proteins (Cas12a and Cas13a) were introduced into the system to recognize and cleave the N gene and ORF1ab gene, respectively. We used fluorescent or CRISPR double digestion test strips to detect the digested products, with the N gene corresponding to the FAM channel in the PCR instrument or the T1 line on the test strip, and the ORF1ab gene corresponding to the ROX channel in the PCR instrument or the T2 line on the test strip. The analysis can be completed in less than 20 min. Meanwhile, we assessed the application of the platform and determined a sensitivity of up to 200 copies/mL. Additionally, dual gene validation in 105 clinical nasopharyngeal swab samples showed a 100% positive predictive value agreement and a 95.7% negative predictive value agreement between our method and quantitative reverse transcription-polymerase chain reaction. Overall, our method offered a novel insight into the rapid diagnosis of SARS-CoV-2.


Assuntos
Proteínas de Bactérias , COVID-19 , Proteínas Associadas a CRISPR , Proteínas do Nucleocapsídeo de Coronavírus , Endodesoxirribonucleases , Fosfoproteínas , Poliproteínas , SARS-CoV-2 , Proteínas Virais , Clivagem do RNA , Clivagem do DNA , SARS-CoV-2/genética , SARS-CoV-2/isolamento & purificação , COVID-19/diagnóstico , Proteínas Virais/genética , Poliproteínas/genética , Proteínas Associadas a CRISPR/química , Proteínas de Bactérias/química , Endodesoxirribonucleases/química , Proteínas do Nucleocapsídeo de Coronavírus/genética , Fosfoproteínas/genética , Humanos
8.
Infect Drug Resist ; 16: 5347-5357, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37605759

RESUMO

Introduction: It is time-consuming to identify fungal pathogens from positive blood cultures using the standard culture-based method. And delayed diagnosis of bloodstream infection leads to significantly increased mortality. Methods: We developed a PCR-reverse dot blot hybridization combined with microfluidic chip techniques to rapidly identify 13 fungal pathogens within 3-4 h using the sample of blood cultured over a period of time. Results: We performed clinical validation using 43 blood culture-positive samples with a sensitivity of 96.7%, a specificity of 100%, and a concordance rate of 97.7%. Samples with different culture durations were evaluated using our approach, showing a detection rate of 85.2% at 16 h and 96.3% at 24 h; the platform could reach a detection limit of 103cfu/mL for the Candida spp. and 103 copies/mL for Aspergillus spp. Discussion: The detection rate of the platform is much higher than the positive rates of concurrent blood cultures. This method bears substantial clinical application potential as it incorporates the microfluidic platform with low reagent consumption, automation, and low cost (about 10 dollars).

9.
J Microbiol Methods ; 211: 106785, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37459923

RESUMO

Diarrhea caused by enteropathogenic bacteria is a major public health issue worldwide, especially in developing countries. In this study, a microfluidic chip-based multiplex polymerase chain reaction (PCR)-reverse dot blot hybridization technology for the rapid and simultaneous detection of 11 enteropathogenic bacteria was developed and the entire process was completed within 3-4 h. The specificity of this method was analyzed using 11 types of pure target bacterial colonies and another 7 types of pure bacterial colonies, and its sensitivity was evaluated with the serial 10-fold dilution of 11 types of pure target bacterial colonies. The detection limit of this method was as low as 103-102 CFU/mL, and it exhibited high specificity for enteropathogenic bacteria. A total of 60 clinical diarrheal fecal samples were detected using this method, the results of which were compared with those of the conventional reference method, which resulted in a positive coincident rate of 100% and a negative coincident rate of 93.75%. Based on the findings, it could be concluded that multiplex PCR-reverse dot blot hybridization based on the microfluidic chip is a rapid, economical, sensitive, specific, and high-throughput method for detecting enteropathogenic bacteria.


Assuntos
Microfluídica , Reação em Cadeia da Polimerase Multiplex , Humanos , Reação em Cadeia da Polimerase Multiplex/métodos , Hibridização de Ácido Nucleico , Análise de Sequência com Séries de Oligonucleotídeos , Diarreia/microbiologia , Bactérias/genética , Sensibilidade e Especificidade
10.
Microbiol Spectr ; 11(4): e0188623, 2023 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-37378559

RESUMO

Clostridioides difficile is one of the leading pathogens causing nosocomial infection. The infection can range from mild to severe, and rapid identification is pivotal for early clinical diagnosis and appropriate treatment. Here, a genetic testing platform for toxins, referred to as OC-MAB (orthogonal CRISPR system combined with multiple recombinase polymerase amplification [RPA]), was developed to detect the C. difficile toxin genes tcdA and tcdB. While recognizing the amplified products of the tcdA gene and the tcdB gene, Cas13a and Cas12a could activate their cleavage activities to cut labeled RNA and DNA probes, respectively. The cleaved products were subsequently identified by dual-channel fluorescence using a quantitative PCR (qPCR) instrument. Finally, they could also be combined with labeled antibodies on immunochromatographic test strips to achieve visual detection. The OC-MAB platform exhibited ultrahigh sensitivity in detecting the tcdA and tcdB genes at levels of as low as 102 to 101 copies/mL. When testing 72 clinical stool samples, the sensitivity (95% confidence interval [CI], 0.90, 1) and specificity (95% CI, 0.84, 1) of the single-tube method based on the fluorescence readout was 100%, with a positive predictive value (PPA) value of 100% (95% CI, 0.90, 1) and a negative predictive value (NPA) value of 100% (95% CI, 0.84, 1), compared to the results of qPCR. Likewise, the sensitivity of the 2-step method based on the test strip readout was 100% (95% CI, 0.90, 1), while the specificity was 96.3% (95% CI, 0.79, 0.99), with a PPA of 98% (95% CI, 0.87, 0.99) and an NPA of 100% (95% CI, 0.90, 1). In short, orthogonal CRISPR technology is a promising tool for the detection of C. difficile toxin genes. IMPORTANCE C. difficile is currently the primary causative agent of hospital-acquired antibiotic-induced diarrhea, and timely and accurate diagnosis is crucial for hospital-acquired infection control and epidemiological investigation. Here, a new method for the identification of C. difficile was developed based on the recently popular CRISPR technology, and an orthogonal CRISPR dual system was utilized for the simultaneous detection of toxin genes A and B. It also uses a currently rare CRISPR dual-target lateral flow strip with powerful color-changing capabilities, which is appropriate for point-of-care testing (POCT).


Assuntos
Sistemas CRISPR-Cas , Clostridioides difficile , Infecções por Clostridium , Técnicas Genéticas , Clostridioides difficile/isolamento & purificação , Infecções por Clostridium/diagnóstico , Cromatografia de Afinidade/métodos , Sensibilidade e Especificidade , Humanos
11.
J Med Virol ; 95(7): e28905, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37386903

RESUMO

The recent major worldwide outbreak of monkeypox virus (MPXV) has highlighted the urgent need for accurate MPXV detection methods. Although quantitative PCR (qPCR) technique is currently the gold standard for MPXV diagnosis, the high costs associated with the technique and the need for complex instrumentation, limits its application in resource-poor settings. CRISPR technology has developed rapidly in recent years and provides an effective tool for point-of-care testing pathogen identification. Here, we exploited the cleavage properties of the Cas12a enzyme and Cas13a enzyme, to detect the MPXV specific genes, F3L gene and B6R gene, respectively. We developed two detection protocols: a 2-step method in which the CRISPR Dual System reaction and the multiplex recombinase polymerase amplification reaction were carried out in separate tubes and a single-tube method in which both reactions were carried out in one tube. Evaluation of the two methods showed that our protocol can detect the MPXV genome down to 10° copies/µL with good specificity and no cross-reactivity with other poxviruses pseudoviruses, and bacteria. Mock positive samples were used to assess clinical applicability, with the results showing satisfactory concordance with the qPCR method for parallel testing. In conclusion, our study provides a reliable molecular diagnostic strategy for detection of MPXV.


Assuntos
Surtos de Doenças , Monkeypox virus , Humanos , Monkeypox virus/genética , Reações Cruzadas , Tecnologia , DNA
12.
Diabetes Metab Syndr Obes ; 16: 1367-1381, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37197060

RESUMO

Background: Fecal microbiota transplantation (FMT) has emerged as a new therapy targeting gastrointestinal microbiota for the treatment of a growing number of diseases in recent years. Previous studies have suggested that FMT may be a potential therapy for type 2 diabetes (T2D), but the underlying mechanism remains unclear. Therefore, in the present study, we aimed to investigate the role of FMT in T2D and its underlying mechanisms. Methods: To induce T2D, mice were fed a high-fat diet and injected with low-dose streptozotocin (STZ) for four weeks. The mice were then randomly divided into four groups: control group (n = 7), T2D group (n = 7), metformin (MET)-treated group (n = 7), and FMT group (n = 7). The MET group was orally administered 0.2 g/kg MET, the FMT group was orally administered 0.3 mL of bacterial solution, and the other two groups were orally administered the same volume of saline for four weeks. Serum and fecal samples were collected for non-targeted metabolomics, biochemical indicators, and 16S rRNA sequencing, respectively. Results: Our results demonstrated that FMT had a curative effect on T2D by ameliorating hyperlipidemia and hyperglycemia. Using 16S rRNA sequencing and serum untargeted metabolomic analysis, we found that FMT could restore the disorders of gastrointestinal microbiota in T2D mice. Moreover, corticosterone, progesterone, L-urobilin, and other molecules were identified as biomarkers after FMT treatment. Our bioinformatics analysis suggested that steroid hormone biosynthesis, arginine, proline metabolism, and unsaturated fatty acid biosynthesis could be potential regulatory mechanisms of FMT. Conclusion: In summary, our study provides comprehensive evidence for the role of FMT in the treatment of T2D. FMT has the potential to become a promising strategy for the treatment of metabolic disorders, T2D, and diabetes-related complications.

13.
Infect Drug Resist ; 16: 2043-2060, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37056484

RESUMO

Background: Bloodstream infection (BSI) is a common type of infection frequently diagnosed in clinics. The emergence and spread of ESBLs-producing Escherichia coli (E. coli) has emerged as one of the biggest challenges in global community health. Methods: The production of ESBLs was determined by the composite disk diffusion method. The expression of the various resistance and virulence genes were detected by PCR and sequencing. Multi-locus sequence typing (MLST) and phylogenetic groups were used for the classification. The transfer of resistant plasmids was determined by conjugation assay. The statistical differences were analyzed using Statistical Product and Service Solutions (SPSS) version 23.0. Results: A total of 60 strains of ESBLs-producing E. coli were collected. The resistance genes that were identified included bla CTX-M, bla TEM, bla SHV, bla OXA-1 and mcr-1. The most common one was the bla CTX-M including bla CTX-M-27 (n = 16), bla CTX-M-14 (n = 15), bla CTX-M-15 (n = 11), bla CTX-M-55 (n = 14) and bla CTX-M-65 (n = 5). A total of 31 STs were detected, and the most abundant among which was ST131 (n = 16, 26.7%). Most of the E. coli (n = 46, 76.7%) belonged to the groups B2 and D. And some virulence genes were related to the classification of the E. coli. Among them, the detection rates of hek/hra, kpsMII and papGII-III in groups B2 and D were higher than those in groups A and B1. The detection rates of cnf1, iucC and papGII-III in ST131 were higher than those in non-ST131. And the distributions of hek/hra, iroN, iucC, kpsMII and papGII-III were related to the bla CTX-M subtypes. Finally, most bacterial (n = 32, 53.3%) resistance genes could be transferred between the bacteria by plasmids, especially IncFIB. Conclusion: ESBLs-producing E. coli in BSI exhibited had high resistance rates and carried a variety of virulence factors (VFs). This is necessary to strengthen the monitoring of ESBLs-producing isolates in the medical environment.

14.
Front Microbiol ; 14: 1119395, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36970685

RESUMO

Purpose: Clostridioides difficile (C. difficile) infection is the most common cause of nosocomial infection, which is a severe challenge in modern medical care. Currently, many laboratory diagnostic methods for C. difficile are available, such as PCR, culture-based tests, and antigen-based tests. However, these methods are not suitable for rapid point-of-care testing (POCT). Therefore, it is of great significance to develop a rapid, sensitive, and cost-effective method to detect C. difficile toxin genes. Methods: Recently, the development of clustered regularly interspaced short palindromic repeats (CRISPR) technology has emerged as a promising tool for rapid POCT. In this study, we developed a rapid and specific detection platform for dual C. difficile toxins by combining recombinase polymerase amplification (RPA) and CRISPR/Cas12a. Results: The platform includes multiplex RPA-cas12a-fluorescence assay and multiplex RPA-cas12a-LFS (Lateral flow strip) assay, through which the detection limit for tcdA and tcdB was 10 copies/µL and 1 copy/µL, respectively. The results can be more clearly distinguished using a violet flashlight, which realized a portable visual readout. The platform can be tested within 50 min. Furthermore, our method did not cross-react with other pathogens that cause intestinal diarrhea. The results of 10 clinical samples using our method was 100% consistent with those from real-time PCR detection. Conclusion: In conclusion, the CRISPR-based double toxin gene detection platform for C. difficile is an effective, specific, and sensitive detection method, which can be used as a powerful on-site detection tool for POCT in the future.

15.
Mol Cell Biochem ; 478(10): 2297-2307, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36735210

RESUMO

Occult hepatitis B virus (HBV) infection (OBI) refers to the presence of replication-competent HBV DNA in the liver, with or without HBV DNA in the blood, in individuals who tested negative for HBV surface antigen (HBsAg). In this peculiar phase of HBV infection, the covalently closed circular DNA (cccDNA) is in a low state of replication. Several advances have been made toward clarifying the mechanisms involved in such a suppression of viral activity, which seems to be mainly related to the host's immune control and epigenetic factors. Although the underlying mechanisms describing the genesis of OBI are not completely known, the presence of viral cccDNA, which remains in a low state of replication due to the host's strong immune suppression of HBV replication and gene expression, appears to be the causative factor. Through this review, we have provided an updated account on the role of HBV cccDNA in regulating OBI. We have comprehensively described the HBV cell cycle, cccDNA kinetics, current regulatory mechanisms, and the therapeutic methods of cccDNA in OBI-related diseases.


Assuntos
Hepatite B Crônica , Hepatite B , Humanos , Vírus da Hepatite B/genética , DNA Circular/genética , DNA Viral/genética , DNA Viral/metabolismo , Hepatite B/genética , Antígenos de Superfície da Hepatite B/genética , Replicação Viral
16.
Infect Drug Resist ; 16: 435-443, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36721635

RESUMO

Introduction: More than half of the world's people are infected or have been infected with Helicobacter pylori. This infection is related to many diseases, with its pathogenicity related to virulence factors. Therefore, the rapid diagnosis of H. pylori and genotyping of virulence genes play an extremely important role in the clinical treatment and control of transmission. Methods: To this end, we developed a molecular detection method based on RPA- CRISPR-Cas12a technology for the specific genes 16S rDNA gene, cytotoxin associated gene A(cagA), and vacuolating cytotoxin A (vacA) of H. pylori. Results: The results of which were displayed by lateral flow strips. Macroscopic observation takes only about 25 minutes and the sensitivity is 2ng/microliter. Discussion: The method is simple, convenient to operate and has low costs, and can therefore be applied widely to the detection and typing of H. pylori in various environments such as primary hospitals, community clinics, outdoors, and large medical institutions.

17.
Lab Med ; 54(4): 372-379, 2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-36282321

RESUMO

OBJECTIVE: The aim of this study was to investigate the association of serum carcinoembryonic antigen (CEA), nerve-specific enolase (NSE), cytokeratin 19 fragment (CYFRA21-1), squamous cell carcinoma antigen (SCC-Ag), and pro-gastrin-releasing peptide (ProGRP) with the clinicopathological characteristics and chemotherapeutic outcomes of patients with lung cancer. METHODS: A total of 189 patients with lung cancer (lung cancer group) diagnosed at the Fourth Affiliated Hospital of Anhui Medical University from January 2020 to December 2021 were included. During the same period, 199 patients with benign lung disorders were included as the benign lung disease group and 75 healthy people were selected as the control group. The serum concentrations of CEA, NSE, CYFRA21-1, SCC-Ag, and ProGRP in all the 3 groups were analyzed and compared in patients with different lung cancer tumor-node-metastasis (TNM) stages and pathological classifications. A total of 11 patients with small cell lung cancer (SCLC) and 18 patients with lung adenocarcinoma (LAC) were further evaluated for the dynamic changes of CEA, NSE, CYFRA21-1, SCC-Ag, and ProGRP before chemotherapy and during the 6 courses of chemotherapy, and the outcome of chemotherapy was evaluated every 2 courses. RESULTS: The serum concentrations of CEA, NSE, CYFRA21-1, SCC-Ag, and ProGRP in the lung cancer group were significantly higher than those in the control group (P < .05). We found statistically significant differences in serum CEA, NSE, CYFRA 21-1, SCC-Ag, and ProGRP among patients with different pathological types (LAC, squamous cell carcinoma, or SCLC) and different stages (I-IV). The ProGRP and NSE had the highest expression in SCLC, CEA showed the highest expression in LAC, whereas CYFRA21-1 and SCC-Ag showed the highest expression in lung squamous cell carcinoma (LSCC). The concentrations of all the markers were elevated in the advanced pathological stages. The receiver operating characteristic curve analysis showed that the diagnostic value of the combined detection of CEA, NSE, CYFRA 21-1, SCC-Ag, and ProGRP for lung cancer was significantly higher than using a single biomarker (P < .05). Our dynamic monitoring results show that ProGRP progressively decreased in remission cases of SCLC and CEA progressively decreased in LAC remission cases. CONCLUSION: CEA, NSE, CYFRA 21-1, SCC-Ag, and ProGRP have good clinical value in the early diagnosis, differential diagnosis, and progression monitoring of lung cancer. The ProGRP and CEA concentrations are beneficial for evaluating the outcome of chemotherapy in SCLC and LAC. The combined detection of multiple biomarkers shows improved clinical value in the early diagnosis of lung cancer.


Assuntos
Carcinoma de Células Escamosas , Pneumopatias , Neoplasias Pulmonares , Humanos , Queratina-19 , Antígeno Carcinoembrionário , Biomarcadores Tumorais , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/tratamento farmacológico , Antígenos de Neoplasias , Fosfopiruvato Hidratase , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/tratamento farmacológico
18.
Infect Drug Resist ; 15: 7389-7399, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36540103

RESUMO

Aim: Hepatitis B surface antibody (HBsAb) plays an important role in the prevention of hepatitis B virus (HBV) infection, especially in immunocompromised individuals and in those infected with HBV.HBsAb levels often fluctuate and decrease.This study aimed to determine the regularity of HBsAb persistence among different populations. Moreover, the risk factors and the optimal cutoff value were determined to predict a decreasing population in HBsAb level. Methods: The study involved 182 participants, including 76 patients with a 25% decrease in HBsAb levels and 106 patients with an HBsAb decrease rate of >50%. Both hepatitis B core antibody negative and positive patients were included.These patients were followed up for 10 years. The follow-up demographic and laboratory data were recorded and compared among the groups. Fluctuations in HBsAb data and HBsAb persistent immunity were evaluated. The independent factors and the optimal cutoff value were recorded. Results: The first HBsAb median of Group 4 was lower than that of the other groups, and its median was 50.8 mlU/mL. In addition, the persistent immunity of the case groups was shorter than that of the control groups (p < 0.05). Furthermore, previous HBV history, use of antiviral drugs, and low levels of first HBsAb were independent risk factors in people with obviously decreased antibody levels. Also, when the optimum cutoff value on the receiver operating characteristic curve of the HBsAb difference value was taken as 8.53 mIU/mL, its sensitivity and specificity were 94% and 70% between the control and case groups, respectively. Conclusion: To maintain optimal immunity against HBV infection, patients with a previous HBV history, those taking antiviral drugs, and/or those with low levels of HBsAb should be reimmunized with the hepatitis B vaccine in a timely manner.

19.
Infect Drug Resist ; 15: 7107-7116, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36506837

RESUMO

Introduction: To examine the in vitro and in vivo antimicrobial activities of ceftazidime/avibactam (CZA) alone or in combination with aztreonam (ATM) against KPC-, NDM-, IMP-, KPC+IMP-, KPC+NDM-producing strains. Methods: A total of 67 clinical non-repetitive carbapenem-resistant Enterobacterales (CRE) strains were selected for the microdilution broth method that was performed to analyze the minimal inhibitory concentration (MIC) and the combination antimicrobial susceptibility test using checkerboard titration method. The fractional inhibitory concentration (FIC) was calculated to determine the antimicrobial effect. The time-kill assays and the mouse infection model were used to study the bactericidal effect and therapeutic effect of CZA alone or in combination with ATM. Results: The CZA minimal inhibitory concentration (MIC) values of CZA revealed that 29 KPC-producing strains and 1 OXA-producing strain were ≤4µg/mL. The CZA MIC values of 37 metal-ß-lactamase (MBLs)-producing strains such as NDM-, IMP-, KPC+IMP-, KPC+NDM-producing strains were ≥128µg/mL, after combining with ATM, the FIC values were all below 0.51. The time-kill assays revealed that CZA at various concentrations of 2, 4 and 8 MIC showed significant bactericidal efficiency to the KPC-producing strains. For NDM-, IMP-producing strains, no colony growth was detected after 8 hours of incubation with CZA in combination with ATM. Six percent of the mice in the treatment group and 58% of the mice in the infection group died within 3 days. Conclusion: Our in vitro results showed that CZA had a good antimicrobial effect on the KPC-producing and OXA-producing strains. CZA combined with ATM showed synergistic bacteriostatic or bactericidal activity against NDM-, IMP-, KPC+IMP-, KPC+NDM-producing strains. The combination of CZA and ATM reduced mortality and prolonged lifespan of mice infected with NDM-, IMP-, KPC+IMP-, and KPC+NDM-producing strains, which provides fundamental knowledge for improving treatment strategies and initializing clinical trials.

20.
Infect Drug Resist ; 15: 1391-1397, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35392368

RESUMO

Aim: To reduce the inspection time for urinary tract pathogens and provide a rapid and effective therapeutic plan for clinical anti-infection treatment, this study developed a rapid identification (ID) and antimicrobial sensitivity test (AST) method by DOT-MGA. Methods: We grouped midstream urine samples with single bacteria according to the number of bacteria (≤5/5-15/≥ 15) under per oil microscope after Gram staining. Then we adopted differential centrifugation to process the grouped samples to collect precipitate. MALDI-TOF MS was performed using precipitate directly or after short-term culture. If succeed, we resuspended the precipitate into droplets with or without antibiotics at a MALDI target. Four hours later, mass spectrometer (MS) was used to identify the culture on the target and to analyse AST. Results: Samples (count ≥ 15), which precipitate can be directly identified by MS; otherwise, the precipitate need a short-term cultured for 3-6 h before ID. The consistency of the ID results between conventional culture and the precipitate is 100%. Compared with broth microdilution method, DOT-MGA for predicting AST had a high consistency. EA and CA for IPM, LEV, CAZ, NIT, and FOT were 100%/100%, 98%/90%, 98%/92%, 100%/90%, 98%/94%, respectively. No VME was observed in all tests. Besides, MIC50 for the five antibiotics by DOT-MGA and broth microdilution method were ≤1/≤0.5,>2/2,≤4/≤2,≤32/≤16,≤64/≤32 and MIC90 were ≤1/≤0.5, >2/>4, 16/16, 128/128, 128/64. Conclusion: This study can shorten the ID time (minimum 0.5h) and AST (minimum 4h) of the main pathogens of urinary tract infection to 5-10 hours, which greatly reduce the inspection time and provide substantial help for the rapid diagnosis and treatment of patients with urinary tract infection.

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