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The global proliferation of carbapenemase-producing bacteria (CPB) has garnered significant attention worldwide. Early diagnosis of CPB and accurate identification of carbapenemases are crucial for preventing the spread of CPB and ensuring targeted antibiotic therapy. Therefore, efficient and accurate identification of carbapenemases is paramount in clinically treating diseases associated with CPB. In this study, 58 CPB strains were collected and detected using the DNA endonuclease-targeted CRISPR trans reporter (DETECTR) method, a rapid detection platform based on CRISPR-Cas12a gene editing and isothermal amplification. Additionally, four conventional methods (the APB/EDTA method, PCR, NG-test Carba 5, and GeneXpert Carba-R) were employed and compared against whole genome sequencing (WGS) results, considered the gold standard, to evaluate their efficacy in detecting carbapenemases. Detection by the APB/EDTA method revealed that 29 strains were positive for Class A serine endopeptidases, while 29 strains were positive for Class B metalloenzymes. The classification of these zymotypes was consistent with the sequencing result. All target carbapenemases for KPC were identified with 100% sensitivity using NG-test Carba 5, PCR, DETECTR, and GeneXpert Carba-R. In the case of NDM, both Xpert Carba-R and DETECTR showed a sensitivity of 100%. In contrast, NG-test Carba 5 and PCR had a slightly lower sensitivity of 96.7%, each missing one target carbapenemase. n this study, the APB/EDTA method is capable of identifying the zymotype classification but not the specific resistant genes, while Xpert Carba-R and DETECTR are able to detect all target carbapenemases.

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.

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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). [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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 blaCTX-M, blaTEM, blaSHV, blaOXA-1 and mcr-1. The most common one was the blaCTX-M including blaCTX-M-27 (n = 16), blaCTX-M-14 (n = 15), blaCTX-M-15 (n = 11), blaCTX-M-55 (n = 14) and blaCTX-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 blaCTX-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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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-β-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. [ABSTRACT FROM AUTHOR]

Legionnaires' disease is a form of atypical pneumonia caused by bacteria of the genus Legionella. L. pneumophila serogroup 1 causes most Legionnaires' disease (1). Although Legionnaires' disease has been reported [...]

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. [ABSTRACT FROM AUTHOR]

Introduction: Carbapenemase-mediated antimicrobial resistance is currently a hot spot of global concern. Carbapenem-resistant organisms are highly prevalent in hospitals associated with difficult-to-treat infections, resulting in poor clinical outcome due to limited treatment options. It is urgently needed to have a rapid, efficient, and convenient molecular assay for identifying such resistant strains. Methods: For this end, we developed a new laboratory assay targeting Klebsiella pneumoniae carbapenemase (KPC) and New Delhi metallo-β-lactamase (NDM) based on loop-mediated isothermal amplification, CRISPR–Cas12a, and lateral flow immunochromatographic strip (CRISPR–Cas-LAMP-lateral flow strip). The method was designed to use a guide RNA (gRNA) to recognize the target DNA and guide Cas12a to cleave the target DNA, and simultaneously cleave any single-stranded DNA within the cleavage reaction system. Results: The cleavage products are visible to the naked eye on the lateral flow strip. This method is highly sensitive in direct detection of bacteria in samples containing at least 3× 105 CFU/mL without the need for bacterial culture. Discussion: It provides shorter turnaround time and higher specificity than the conventional bacterial culture and susceptibility testing method. This new assay is applicable for extensive use in hospital infection control, as well as identification and treatment of resistant strains due to simple operation and inexpensive apparatuses. [ABSTRACT FROM AUTHOR]

Introduction: The recently developed DOT-MGA (direct-on-target microdroplet growth assay) has shown the desirability of direct application of this approach in positive blood cultures and its good performance in detection. This study selected 44 Enterobacteriaceae strains and implemented a DOT-MGA assay on blood cultures to detect their resistance to seven antibiotics. The results of DOT-MGA were compared with the other two antimicrobial susceptibility testing (AST) methods to analyze the detection performance of DOT-MGA. Methods: We adopted the differential centrifugation to process positive blood-culture (BC). Processed BC broth was directly used for rapid AST using DOT-MGA. Droplets of 6 μL with and without antibiotics at the EUCAST breakpoint concentration were spotted in triplicates onto the surface of a MALDI target. The plates were incubated in a wet box for 4 h before the broth was removed with filter paper. Bruker Biotyper software was used to analyze the test results compared with standard database, and the scores were used to quantify and determine the results. Results: DOT-MGA results were compared with the direct-from-BC disk-diffusion method and results were reported by broth microdilution method, respectively. The comparison demonstrated a 100% growth efficiency in DOT-MGA, a 100% classification consistency for ampicillin, ceftriaxone, and gentamicin, and > 93% classification consistency for tobramycin, aztreonam, trimethoprim-sulfamethoxazole (TMP-SMX), and ceftazidime. Discussion: These study results have shown that DOT-MGA is suitable for directly identifying bacterial resistance to positive blood cultures in clinical microbiology laboratories. Furthermore, it is conducive for early diagnosis and treatment of patients with bloodstream infection due to its convenience, time efficiency, and good performance in identifying multiple antibiotic-insensitive bacteria. [ABSTRACT FROM AUTHOR]

Liver cancer (LC), which is one of the most common types of cancer worldwide, is notorious for its high morbidity and mortality rates. Interleukin-8 (IL-8), an important member of the CXC chemokine family that was originally classified as a potent neutrophil chemoattractant, has been shown to serve an important role in inflammation, tumor growth, invasion and metastasis through interactions with its receptors. However, the expression and functional roles of IL-8 and its receptors, CXC chemokine receptor (CXCR) 1 and CXCR2 in the progression of liver cancer remain to be fully elucidated. In the present study, it was shown that the mRNA levels of IL-8, CXCR1 and CXCR2 were increased in peripheral blood mononuclear cells from patients with liver cancer compared with those from patients with cirrhosis or normal controls (P<0.05). Higher levels of CXCR1, CXCR2 and IL-8 were associated with advanced tumor stage and increased risk of lymph node or distant metastasis. Immunohistochemistry showed that the IL-8, CXCR1 and CXCR2 proteins were expressed in the cytoplasm of hepatoma cells at higher intensities than those of normal controls (P<0.05). The semi-quantitative analysis revealed that the relative mean density of hepatic IL-8, CXCR1 and CXCR2 staining in liver cancer was significantly increased compared with that in normal liver tissues (P<0.05). The analysis revealed that the mRNA expression of IL-8 was positively associated with that of CXCR1 (r=0.618; P<0.05) and CXCR2 (r=0.569; P<0.05). The mRNA levels of CXCR1 and CXCR2 gradually increased with elevated expression of IL-8 in liver cancer. Experiments were performed using human Huh-7 and HepG2 cell lines, incubating cells with IL-8 and conducting in vitro migration and invasion assays. The results showed that the wound healing activity and migration of Huh-7 and HepG2 cells were increased by IL-8. Pretreatment of the cells with anti-CXCR1 or anti-CXCR2 (5 µM) for 30 min markedly inhibited IL-8-directed cell migration. Taken together, these results indicated that IL-8 promotes liver cancer cell migration via CXCR1 and CXCR2 and that targeting the CXCR1/2 may be a potential strategy for liver cancer treatment. [ABSTRACT FROM AUTHOR]

Background: Colistin has been considered as one of the most effective treatments in clinical infections, especially multidrug-resistant (MDR) bacteria-infected patients. The mcr-1 gene leads to polymyxin resistance in China. The present study investigated the prevalence of mcr-1 in a Chinese teaching hospital, and the molecular phenotypes of the positive strains were analyzed. Methods: A total of 1,112 Escherichia coli strains were collected from a Chinese University Hospital from January 2015 to January 2016. The mcr-1 gene was detected by PCR. All positive specimens were subjected to susceptibility testing, clinical analysis, phylogenetic analysis, DNA Southern blot hybridization, and gene sequencing. Results: Six (0.6%) strains of mcr-1-positive E. coli were susceptible to imipenem, meropenem, and tigecycline, except for one that presented moderate levels of tigecycline resistance. The six isolates were resistant to cefotaxime and cefepime and divided into six types of sequences. These positive strains carried a total of three plasmids: approximately 33, 61, and >92 kb plasmids. All patients were eventually cured using different types of antibiotics and discharged. Conclusion: The current study showed that the mcr-1 gene was responsible for the majority of colistin resistance in clinical isolates of E. coli. The gene can be transferred into plasmids containing other drug resistance genes by plasmid–DNA conjugation, which might cause severe consequences in drug-resistant strains. Thus, the widespread popularity of mcr-1 gene should be prevented. [ABSTRACT FROM AUTHOR]

We investigated the relationship between the outer membrane protein OprD2 and carbapenem-resistance in 141 clinical isolates of Pseudomonas aeruginosa collected between January and December 2013 from the First Affiliated Hospital of Anhui Medical University in China. Agar dilution methods were employed to determine the minimum inhibitory concentration of meropenem (MEM) and imipenem (IMP) for P. aeruginosa. The gene encoding OprD2 was amplified from141 P. aeruginosa isolates and analyzed by PCR and DNA sequencing. Differences between the effects of IMPR and IMPS groups on the resistance of the P. aeruginosa were observed by SDS-poly acrylamide gel electrophoresis (SDS-PAGE). Three resistance types were classified in the 141 carbapenem-resistant P. aeruginosa (CRPA) isolates tested, namely IMPRMEMR (66.7%), IMPRMEMS (32.6%), and IMPRMEMS (0.7%). DNA sequencing revealed significant diverse gene mutations in the OprD2-encoding gene in these strains. Thirty-four strains had large fragment deletions in the OprD2gene, in 6 strains the gene contained fragment inserts, and in 96 resistant strains, the gene featured small fragment deletions or multi-site mutations. Only 4 metallo-β-lactamase strains and 1 imipenem-sensitive (meropenem-resistant) strain showed a normal OprD2 gene. Using SDS-PAGE to detect the outer membrane protein in 16 CRPA isolates, it was found that 10 IMPRMEMR strains and 5 IMPRMEMS strains had lost the OprD2 protein, while the IMPSMEMR strain contained a normal 46-kDa protein. In conclusion, mutation or loss of the OprD2-encoding gene caused the loss of OprD2, which further led to carbapenem-resistance of P. aeruginosa. Our findings provide insights into the mechanism of carbapenem resistance in P. aeruginosa. [ABSTRACT FROM AUTHOR]

We report national surveillance of Legionnaires' disease in China. Urine samples from 11 (3.85%) of 286 patients with severe pneumonia of unknown cause were positive for the Legionella pneumophila serogroup 1 antigen. We isolated Legionella strains from 7 patients. Improved diagnostic testing is needed for this underestimated disease in China. [ABSTRACT FROM AUTHOR]

Purpose: Population mobility significantly contributes to the spread and prevalence of infectious diseases, posing a serious threat to public health safety and sustainable development across the globe. Understanding the impact of population mobility on the prevention and control of infectious diseases holds profound significance., Methods: In this study, we collected the data on the incidence of notifiable infectious diseases in mainland China from 2013 to 2019, and analyzed the characteristics of notifiable infectious diseases, as well as their correlation with transportation passenger traffic., Results: Among 29 common notifiable infectious diseases, the incidence rate of intestinal diseases per 100,000 people was the highest (256.35 cases), while the mortality rate was the lowest (0.017 cases). The mortality rate per 100,000 people due to sexually transmitted and bloodborne diseases was the highest (1.154 cases). A significant linear correlation was noted between commercial passenger traffic and the number of cases of tuberculosis (r = 0.83, P = 0.022), hepatitis A (r = 0.87, P = 0.012), bacillary and amebic dysentery (r = 0.90, P = 0.006), typhoid/paratyphoid (r = 0.94, P = 0.002), leptospirosis (r = 0.90, P = 0.005), AIDS(r=-0.90, P = 0.006), gonorrhea (r=-0.79, P = 0.035) and scarlet fever (r=-0.85, P = 0.016). A significant linear correlation was noted between public transportation passenger traffic and the number of cases of measles (r = 0.94, P = 0.002), hepatitis A (r = 0.96, P = 0.001), parasitic and vector-borne diseases (r = 0.96, P = 0.001), brucellosis (r = 0.95, P = 0.001), leptospirosis (r = 0.88, P = 0.008), other infectious diarrhea (r = 0.86, P = 0.013) and gonorrhea (r = 0.84, P = 0.018)., Conclusion: The results of this study indicated that transportation passenger traffic significantly affected the incidence of infectious diseases, and reasonable management of passenger traffic was a potentially important means of prevention and control of infectious diseases., (© 2024. The Author(s).)

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 10 2 to 10 1 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)., Competing Interests: The authors declare no conflict of interest.

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., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Jiang, Hu, Lin, Xia, Yang, Zhu, Xu, Tang and Shen.)

Introduction: This study aims to investigate patterns of antibiotic treatment-seeking, describe current levels of and drivers for antibiotic use for common infections (respiratory tract and urinary tract infections) and test the feasibility of determining the prevalence and epidemiology of antimicrobial resistance (AMR) in rural areas of Anhui province, in order to identify potential interventions to promote antibiotic stewardship and reduce the burden of AMR in China., Methods and Analysis: We will conduct direct observations, structured and semistructured interviews in retail pharmacies, village clinics and township health centres to investigate treatment-seeking and antibiotic use. Clinical isolates from 1550 sputum, throat swab and urine samples taken from consenting patients at village and township health centres will be analysed to identify bacterial pathogens and ascertain antibiotic susceptibilities. Healthcare records will be surveyed for a subsample of those recruited to the study to assess their completeness and accuracy., Ethics and Dissemination: The full research protocol has been reviewed and approved by the Biomedical Ethics Committee of Anhui Medical University (reference number: 20170271). Participation of patients and doctors is voluntary and written informed consent is sought from all participants. Findings from the study will be disseminated through academic routes including peer-reviewed publications and conference presentations, via tailored research summaries for health professionals, health service managers and policymakers and through an end of project impact workshop with local and regional stakeholders to identify key messages and priorities for action., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2019. Re-use permitted under CC BY. Published by BMJ.)

Patients with bloodstream infections (BSI) are associated with high mortality rates. Due to tigecycline has shown excellent in vitro activity against most pathogens, tigecycline is selected as one of the candidate drugs for the treatment of multidrug-resistant organisms infections. The purpose of this study was to evaluate the effectiveness and safety of the use of tigecycline for the treatment of patients with BSI. The PubMed and Embase databases were systematically searched, to identify published studies, and we searched clinical trial registries to identify completed unpublished studies, the results of which were obtained through the manufacturer. The primary outcome was mortality, and the secondary outcomes were the rate of clinical cure and microbiological success. 24 controlled studies were included in this systematic review. All-cause mortality was lower with tigecycline than with control antibiotic agents, but the difference was not significant (OR 0.85, [95% confidence interval (CI) 0.31-2.33; P = 0.745]). Clinical cure was significantly higher with tigecycline groups (OR 1.76, [95% CI 1.26-2.45; P = 0.001]). Eradication efficiency did not differ between tigecycline and control regimens, but the sample size for these comparisons was small. Subgroup analyses showed good clinical cure result in bacteremia patients with CAP. Tigecycline monotherapy was associated with a OR of 2.73 (95% CI 1.53-4.87) for mortality compared with tigecycline combination therapy (6 studies; 250 patients), without heterogeneity. Five studies reporting on 398 patients with Klebsiella pneumoniae carbapenemase-producing K. pneumoniae BSI showed significantly lower mortality in the tigecycline arm than in the control arm. The combined treatment with tigecycline may be considered the optimal option for severely ill patients with BSI.

We investigated the relationship between the outer membrane protein OprD2 and carbapenem-resistance in 141 clinical isolates of Pseudomonas aeruginosa collected between January and December 2013 from the First Affiliated Hospital of Anhui Medical University in China. Agar dilution methods were employed to determine the minimum inhibitory concentration of meropenem (MEM) and imipenem (IMP) for P. aeruginosa. The gene encoding OprD2 was amplified from141 P. aeruginosa isolates and analyzed by PCR and DNA sequencing. Differences between the effects of IMPR and IMPS groups on the resistance of the P. aeruginosa were observed by SDS-poly acrylamide gel electrophoresis (SDS-PAGE). Three resistance types were classified in the 141 carbapenem-resistant P. aeruginosa (CRPA) isolates tested, namely IMPRMEMR (66.7%), IMPRMEMS (32.6%), and IMPRMEMS (0.7%). DNA sequencing revealed significant diverse gene mutations in the OprD2-encoding gene in these strains. Thirty-four strains had large fragment deletions in the OprD2gene, in 6 strains the gene contained fragment inserts, and in 96 resistant strains, the gene featured small fragment deletions or multi-site mutations. Only 4 metallo-β-lactamase strains and 1 imipenem-sensitive (meropenem-resistant) strain showed a normal OprD2 gene. Using SDS-PAGE to detect the outer membrane protein in 16 CRPA isolates, it was found that 10 IMPRMEMR strains and 5 IMPRMEMS strains had lost the OprD2 protein, while the IMPSMEMR strain contained a normal 46-kDa protein. In conclusion, mutation or loss of the OprD2-encoding gene caused the loss of OprD2, which further led to carbapenem-resistance of P. aeruginosa. Our findings provide insights into the mechanism of carbapenem resistance in P. aeruginosa.

Fungal infections in the clinic have become increasingly serious. In many cases, the identification of clinically relevant fungi remains time-consuming and may also be unreliable. Matrix-assisted laser desorption ionization-time of flight mass spectroscopy (MALDI-TOF MS) is a newly developed diagnostic tool that is increasingly being employed to rapidly and accurately identify clinical pathogenic microorganisms. The present meta-analysis aimed to systematically evaluate the accuracy of MALDI-TOF MS for the identification of clinical pathogenic fungi. After a rigorous selection process, 33 articles, involving 38 trials and a total of 9,977 fungal isolates, were included in the meta-analysis. The random-effects pooled identification accuracy of MALDI-TOF MS increased from 0.955 (95% confidence interval [CI], 0.939 to 0.969) at the species level to 0.977 (95% CI, 0.955 to 0.993) at the genus level (P < 0.001; χ(2) = 15.452). Subgroup analyses were performed at the species level for several categories, including strain, source of strain, system, system database, and modified outcomes, to calculate the accuracy and to investigate heterogeneity. These analyses revealed significant differences between the overall meta-analysis and some of the subanalyses. In parallel, significant differences in heterogeneity among different systems and among different methods for calculating the identification ratios were found by multivariate metaregression, but none of the factors, except for the moderator of outcome, was significantly associated with heterogeneity by univariate metaregression. In summary, the MALDI-TOF MS method is highly accurate for the identification of clinically pathogenic fungi; future studies should analyze the comprehensive capability of this technology for clinical diagnostic microbiology., (Copyright © 2014, American Society for Microbiology. All Rights Reserved.)