Drug Resistance Rate Research Articles

Evaluation of Clinical Distribution and Antimicrobial Resistance of Klebsiella Pneumoniae

Purpose: This paper aims to analyze the clinical distribution and drug resistance changes of Klebsiella Pneumoniae (KPN) from 2017 to 2021 in the Beijing Hospital of Integrated Traditional Chinese and Western Medicine to provide a reference for the clinical rational use of antibiotics. Methods: We collected Klebsiella Pneumoniae isolated from various clinical specimens in 2017-2021, analyzed the isolation rate, specimen distribution, and department distribution characteristics during the five years, and statistically analyzed their drug sensitivity tests and multiple drug resistance. Zhuhai Deere DL-96 full-automatic microbial analyzer was used for bacterial identification and drug sensitivity tests. The drug sensitivity test was interpreted according to the standards recommended by the American Clinical and Laboratory Standards Institute (CLSI). Results: A total of 1057 strains of Klebsiella Pneumoniae were identified between 2017 and 2021, with proportions of 18.6%, 15.7%, 15.4%, 15.1%, and 15.0% in each respective year. Specimen distribution included sputum (66.0%), urine (17.9%), throat swab (9.4%), secretion (2.4%), pus (0.7%), venous blood (0.6%), vaginal swab (0.4%), and other sources (2.6%). Distribution by the department revealed specimens originating from the respiratory department (21.2%), cardiology department (17.8%), neurology department (13.4%), oncology department (13.0%), nephrology department (12.2%), acupuncture department (10.1%), and other departments (12.3%). In terms of drug susceptibility testing, Klebsiella Pneumoniae exhibited high resistance rates to ceftriaxone, cefotaxime, ceftazidime, and ampicillin/sulbactam, with rates of 50.8%, 46.8%, 46.3%, and 43.6% respectively. Conversely, resistance rates to minocycline, amikacin, imipenem, and meropenem were relatively low, at 8.6%, 16.5%, 8.5%, and 9.4% respectively. Resistance rates to cefepime/- sulbactam and piperacillin/tazobactam were 29.9% and 28.9%, respectively, while cephalosporin resistance rates ranged from 36.1% to 50.8%. Regarding multidrug resistance, the detection rates of ESBL-producing Klebsiella Pneumoniae were 8.2%, 10.9%, 4.5%, 10.6%, and 6.4% from 2017 to 2021, with an average detection rate of 7.9%. The detection rates of CR-Kp were 12.1%, 11.7%, 5.8%, 9.9%, and 8.9% respectively, averaging 9.6% over the five-year period. Conclusion: The sputum specimen of Klebsiella Pneumoniae exhibits the highest detection rate among specimen distributions, signifying its significance as a pathogenic bacterium in respiratory tract infections. Notably, the respiratory department demonstrates the highest detection rate, underscoring the necessity to enhance the monitoring and management of Klebsiella Pneumoniae infections in respiratory patients. Over the past five years, our hospital has observed a decreasing trend in the overall drug resistance rate of Klebsiella Pneumoniae to 17 antibiotics. While imipenem and meropenem exhibit minimal resistance rates, these carbapenem antibiotics serve as crucial agents for treating gram-negative bacilli, particularly in critically ill patients, and are thus not recommended as first-line choices for routine clinical use. Conversely, minocycline, amikacin, ceftazidime/ sulbactam, and piperacillin/tazobactam showcase relatively low resistance rates, enabling their empirical use based on clinical experience. Combination therapy with other antibiotics is advised for amikacin. Conclusion: Nevertheless, cephalosporins display a relatively high resistance rate, necessitating a reduction in their clinical utilization. Regarding multidrug resistance, the detection of ESBLs-producing Klebsiella Pneumoniae (KP) and Carbapenem-Resistant KP (CR-Kp) has exhibited a declining trend over the past three years. Despite this positive trend, the issue of multidrug resistance in Klebsiella Pneumoniae remains severe, with instances of complete drug resistance reported. Clinicians are urged to judiciously administer antibiotics guided by drug sensitivity test results and resistance rate variations, restrict the use of broad-spectrum antibiotics, and manage the emergence and spread of ESBLs-producing and CR-Kp bacteria.

Analysis of virus gene subtypes and drug resistance monitoring results of newly reported HIV/AIDS population in Anhui Province from 2020 to 2023

Objective: To investigate the genetic subtypes and drug resistance monitoring of newly reported human immunodeficiency virus (HIV) infection/AIDS virus in Anhui Province from 2020 to 2023. Methods: An observational design study was used to collect blood samples from patients diagnosed with HIV/AIDS in the AIDS Prevention and Control Department of Anhui Provincial Center for Disease Control and Prevention from January 2020 to December 2023.The HIV-1 pol gene was amplified by reverse transcription-nested PCR, and the genetic subtypes were identified by phylogenetic tree analysis using MEGA 7.0 software. The mutation sites of drug resistance were analyzed by the online software tool of Stanford University's HIV Drug resistance database. The influencing factors of drug resistance before treatment were analyzed by multivariate logistic analysis. Results: A total of 335 plasma samples were collected, and 332 HIV-1 pol gene sequences were obtained successfully. The main gene subtypes were CRF01-AE, accounting for 35.55% (118/332), followed by CRF07-BC, B and B+C types [29.22% (97/332), 11.74% (39/332), 9.93% (33/332)]. The total drug resistance rate before treatment was 30.12%(32/100), and the drug resistance rate of protease inhibitor (PIs) in HIV-1 was 6.33% (21/332). The drug resistance rate of nucleoside reverse transcriptase inhibitors (NRTI) before treatment was 6.33% (21/332). The drug resistance rate of non-nucleoside reverse transcriptase inhibitors (NNRTI) before treatment was 17.47% (58/332).The comparison of drug resistance rate of different drug types showed statistical significance (χ2=30.435, P<0.05).Among the 100 cases of drug resistance, the main mutation point of HIV-1 protease inhibitor was Q58E (21.00%), and the main mutation point of nucleoside reverse transcriptase inhibitor was M184V/I (6.00%). Non-nucleoside reverse transcriptase inhibitor resistance mutation points mainly K103N (22.00%).There were statistically significant differences in the starting time of antiviral therapy, the number of CD4+T cells at baseline and the drug resistance rate of gene subtypes (the chi-square values are respectively 24.152, 32.516, 11.652, P<0.05).Multivariate logistic analysis showed that the baseline CD4+T cell count was <200/μl, subtype B, subtype B+C, CRF01-AE subtype, CRF55-01B subtype and 01-BC subtype was the influential factor of drug resistance before treatment (the chi-square values are respectively 4.577, 8.202, 4.416, 5.206, 7.603 and 4.804, P<0.05). Conclusion: The newly reported HIV/AIDS population in Anhui Province from 2020 to 2023 has a variety of viral gene subtypes, and NNRTIs are the main types of drug resistance gene mutations before treatment. Attention should be paid to the number of baseline CD4+T cells, the duration of antiviral treatment, and the distribution of gene subtypes to reduce the drug resistance of HIV/AIDS patients before treatment.

Analysis of epidemiological characteristics of extrapulmonary tuberculosis from South-Central China.

This study aimed to investigate the epidemiological and drug resistance (DR) characteristics of extrapulmonary tuberculosis (EPTB) in South-Central China. EPTB inpatients who were culture-positive for Mycobacterium tuberculosis were retrospectively included in a study at a provincial TB hospital in Hunan, a province in South-Central China, from January 2013 to December 2021. Demographic, clinical, and drug susceptibility data were retrieved from TB treatment records. Descriptive statistical methods and a Chi-squared test were used to analyze the epidemiological and DR characteristics of EPTB patients. A logistic regression model was used to explore the risk factors of rifampicin-resistant/multidrug-resistant (RR/MDR)-EPTB. A total of 1,324 cases were included. The majority of EPTB patients were in the age range of 20-29 years, were predominantly men (male-to-female ratio: 2.03), and were farmers (65.63%). Most EPTB cases were found in 2013 and 2017 from 2013 to 2021. The most prevalent subtypes of EPTB were lymphatic TB (29.83%, 395/1,324), multiple EPTB (20.85%, 276/1,324), and musculoskeletal TB (14.65%, 194/1,324). Musculoskeletal TB and genitourinary TB predominantly presented as exclusive EPTB forms, while lymphatic TB and pharyngeal/laryngeal TB often co-occurred with pulmonary TB (PTB). Drug susceptibility testing results showed that total DR rates (resistance to any of RFP, isoniazid [INH], streptomycin [STR], and/or ethambutol [EMB]) and RR/MDR rates in EPTB were 25.23% and 12.39%, respectively. Musculoskeletal TB exhibited the highest rates of total DR (31.40%), INH resistance (28.90%), STR resistance (20.10%), EMB resistance (6.20%), MDR (13.90%), and poly-DR (6.70%). The multivariable logistic regression model showed that patients aged from 20 to 59 years (compared to those aged 10 years), workers (compared to retirees), and EPTB patients from the south and west of Hunan (compared to those from the east of Hunan) were at an increased risk of developing RR/MDR EPTB (all OR values > 1). Our study provided a detailed account of the epidemiological and DR characteristics of EPTB in Hunan province, China. The significant DR rates, particularly in musculoskeletal TB cases, highlight the need for timely diagnosis, effective drug susceptibility testing, and the development of more effective treatment regimens for EPTB, especially targeting musculoskeletal TB treatments.

Efficacy of epetraborole against Mycobacteroides abscessus in a mouse model of lung infection.

Mycobacteroides abscessus (Mab or Mycobacterium abscessus) is a fast-growing mycobacterium that is ubiquitous in the environment and can cause opportunistic disease in people with lung comorbidity and immunodeficiency. There are no Food and Drug Administration-approved drugs for this disease, and repurposed antibiotics have a poor microbiological response. To address the need for effective new antibiotics, we determined the efficacy of epetraborole (EBO) against three Mab clinical isolates in a mouse model of lung Mab infection. Reduction in lung Mab burden over 4 weeks of treatment was the study end point. EBO was administered orally once daily at doses of 25 and 50 mg/kg, which achieved exposures approximating the once-daily dosing of 250 mg and 500 mg, respectively, in humans. EBO administration led to a gradual reduction in the lung Mab burden. After 4 weeks of treatment, the efficacies of 25 and 50 mg/kg EBO against isolates ATCC 19977 and M9501 were comparable. However, against isolate M9530, 50 mg/kg EBO was more efficacious than 25 mg/kg and comparable with parenteral imipenem, one of the most efficacious antibiotics against Mab. We also undertook a dose-ranging study by evaluating the efficacies of once-daily oral administration of 0.5, 5, 10, 25, and 100 mg/kg EBO against M9501 over 4 weeks. Once-daily oral 100 mg/kg EBO was as effective as twice-daily 100 mg/kg imipenem injection. Our study suggests that EBO could address the unmet need for effective oral treatment options for Mab lung disease, given the high rates of Mab drug resistance and limited tolerable intravenous options.

Following the Trace of Cyclodextrins on the Selenium and Tellurium Odyssey.

There is an urgent need to develop safer and more effective modalities for the treatment of numerous pathologies due to the increasing rates of drug resistance, undesired side effects, poor clinical outcomes, etc. Over the past decades, cyclodextrins (CDs) have gathered great attention as potential drug carriers due to their ability to enhance their bioactivities and properties. Likewise, selenium (Se) and tellurium (Te) have been extensively studied during the last decades due to their possible therapeutical applications. Although there is limited research on the relationship between Se and Te and CDs, herein, we highlight different representative examples of the advances related to this topic as well as give our view on the future directions of this emerging area of research. This review encompasses three different aspects of this relationship: (1) modification of the structure of the different CDs; (2) formation of host-guest interaction complexes of naïve CDs with Se and Te derivatives in order to overcome specific limitations of the latter; and (3) the use of CDs as catalysts to achieve novel Se and Te compounds.

HIV1 drug resistance among patients experiencing first-line treatment failure in Ethiopia: protocol for a systematic review and meta-analysis

BackgroundThe emergence of HIV drug resistance presents a substantial challenge. Current antiretroviral treatments, along with current classes, face the danger of becoming partially or entirely inactive. As a result, alternative treatment regimens are limited, and treatment choices are complicated. According to the recommendation of the WHO, nations should consider changing their first-line ART regimen if HIV drug resistance exceeds 10%. In spite of the fact that a number of primary studies have been performed on HIV drug resistance in Ethiopia, their pooled prevalence rate has not been determined in a systematic review and meta-analysis, which may provide stronger evidence. Therefore, the objective of this systematic review and meta-analysis will be to estimate the pooled prevalence rate of HIV1 drug resistance in patients with first-line treatment failure in Ethiopia.MethodsPrimary studies will be identified from PubMed/MEDLINE, Scopus, Embase, Web of Science Core Collection, and Google Scholar. The period of search will be from 01 April to 30 June 2024. Studies identified through the search strategies will first be screened by titles and abstracts. Included studies meeting established criteria will be evaluated for risk of bias using the JBI checklist. Data will be extracted, and the pooled prevalence rate of HIV drug resistance will be computed using STATA 14 software. Random effect models will be used when heterogeneity is suspected. The I2 statistic and its corresponding P value will be checked to distinguish heterogeneity. Additionally, publication bias and heterogeneity will be checked using visual funnel plots, Egger’s test, trim-and-fill tests, meta-regression, and subgroup analysis. To present and synthesize the results, narrative synthesis will be performed to describe study characteristics and findings, and forest plots will be used to visually represent effect sizes and confidence intervals from individual studies.DiscussionEstimating the pooled prevalence rate of HIV drug resistance through a systematic review and meta-analysis improves the reliability of the evidence, the availability of effective HIV treatment options, and the ability to assist in making decisions for both clinical practice and public health policy in Ethiopia.Systematic review registrationPROSPERO CRD42024533975.

NGS mutational status on first diagnostic tissue, liquid biopsy and mastectomy in G2-G3 breast cancer.

Breast cancer is one of the more frequently diagnosed cancers leading to death in women, and, like other tumor types, it is heterogeneous in its immunophenotype. It harbors mutations that modify tumor aggressiveness, therapy responses, residual disease, drug resistance, and relapse rates in advanced stages. This study aims to assess the mutational status of G2 and G3 tumors using next-generation sequencing (NGS) on initial tissue biopsies, liquid biopsies, and mastectomy specimens. The histopathological (HP) diagnosis for the 32 selected cases was established via Hematoxylin-Eosin (HE) staining by two observers. For the immunohistochemical (IHC) testing of estrogen receptor (ER), progesterone receptor (PGR) and human epidermal growth factor receptor 2 (HER2), we used the Ventana BenchMark Ultra. Ki67 testing was conducted using Bond-III from Leica. For cases with a score of 2+, gene amplification was assessed by silver-enhanced in situ hybridization (ISH) (SISH; Inform HER2 Dual ISH) on Ventana BenchMark Ultra. NGS analysis was initially performed on biopsies and plasma, and later on mastectomy specimens. After automated deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) extraction, concentrations were measured using the Invitrogen Qubit system. Libraries were created using Oncomine systems, and sequencing and analysis were done with the Ion Torrent system. Most tumors were graded as G3 (19 cases), with Luminal A being the predominant molecular subtype, and a significant number displayed HER2∕HER2-low characteristics (24 out of 32 cases). The NGS assessment showed that phosphatidylinositol-4,5-bisphosphate 3-kinase, catalytic subunit alpha (PIK3CA) mutations were the most frequent across all sample types. A significant limitation was the high number of invalid plasma tests due to pre-analytical handling errors or transport issues. Nonetheless, plasma testing (liquid biopsy) proved useful for monitoring tumor evolution and assessing residual disease.

Treatment Related Factors Associated with Non-adherence to Anti-Tuberculosis Treatment

Background: Non-adherence to anti-tuberculosis treatment may result in persistent infectiousness on the part of the patient and a higher rate of treatment failure, relapse and drug resistance and therefore, is a significant barrier to the success in tuberculosis control. Objective: To determine the treatment related factors associated with non-adherence to anti-tuberculosis treatment among tuberculosis patients. Materials and method: This case control study was carried out among purposively selected 47tuberculosis patients non-adherent to treatment (cases) and 94 tuberculosis patients adherent to treatment (controls) and were interviewed with a semi-structured questionnaire and checklist in selected DOTS centres of Dhaka city. Results: Statistical analysis shows that, factors like delay in seeking tuberculosis treatment for &gt;6 weeks (OR=4.57; 95% CI, 1.48-14.1) and getting medicine weekly once (OR=2.8; 95% CI, 1.13-6.77) were more likely to be associated with non-adherence to treatment. Lessfrequent visit by health providers (p=0.02), no support for side effect (p=0.042) and non-observation of medication (p=0.009) were also found significant. The reasons behind missing anti-TB doses among non-adherent cases were due to feeling better (53.2%), personal reason (25.5%), feeling worse (19.1%) and forgot to take medicine (2.2%). Conclusion: Mass awareness among the tuberculosis patients is required to improve attitude towards anti-tuberculosis treatment and activities of tuberculosis control programme require further strengthening especially in targeting the patients of low economic status. Delta Med Col J. Jan 2021;9(2): 96-100

Epidemiological characteristics and drug resistance of diarrheagenic Escherichia coli infection in diarrhea patients in Shanghai, 2016-2022

Objective: To understand the infection status, epidemiological characteristics and drug resistance of Diarrheagenic Escherichia coli (DEC) in Shanghai and provide evidence for the disease surveillance. Methods: The epidemiological data of diarrhea cases in Shanghai from 2016 to 2022 were collected from Shanghai Diarrhea Comprehensive Surveillance System, and stool samples were collected from the cases for DEC detection. The drug resistance data was obtained from Chinese Pathogen Identification Network. Statistical analysis was conducted by using χ2 and fisher test. Results: In 24 883 diarrhea cases detected during 2016-2022, the DEC positive rate was 9.13% (2 271/24 883), the single DEC positive rate was 8.83% (2 197/24 883) and the mixed DEC positive rate was 0.30% (74/24 883). The main type of DEC was Enterotoxigenic Escherichia coli (ETEC) [4.33% (1 077/24 883)]. The DEC positive rate was highest in people aged ≤5 years 18.48% (22/119). The annual peak of DEC positive rate was observed during July - September [5.91% (1 470/24 883)]. The DEC positive rate were 9.47% (554/5 847) and 9.02% (1 717/19 036) in urban area and in suburbs, respectively, Enteroaggregative Escherichia coli (EAEC) [3.98% (233/5 847)] and ETEC [4.56% (868/19 036)] were mainly detected. From 2016 to 2019, the DEC positive rate was 9.42% (1 821/19 330), while it was 8.10% (450/5 553) from 2020 to 2022, the main DEC types were ETEC (4.87%, 941/19 330) and EAEC (4.70%, 261/5 553). The multi-drug resistance rate was 40.21% (618/1 537). The top three antibiotics with high drug resistance rates were ampicillin [64.74% (995/1 537)], nalidixic acid [58.49% (899/1 537)] and tetracycline [45.09% (693/1 537)]. Conclusions: Compared with 2016- 2019, a decrease in DEC detection rate was observed during 2020-2022, and the main type of DEC detected shifted from ETEC to EAEC. The prevalence of multi-drug resistance was severe. Therefore, it is necessary to further strengthen the surveillance for DEC drug resistance and standardize the use of clinical antibiotics.

Adhesin Component Member STAG2 Enhances Cisplatin Tolerance in Colorectal Cancer Cells through the Epithelial-Mesenchymal Transition Pathway.

Platinum-based compounds are commonly used as an initial treatment for colorectal cancer (CRC). However, the development of drug resistance in patients with CRC necessitates the administration of high drug concentrations during clinical treatment, thereby augmenting the toxicity of platinum-based compounds and increasing the mortality rate. STAG2 is a significantly associated drug-resistance gene in many cancers, but it has not been studied in colorectal cancer. Therefore, the present study aimed to investigate the role and drug sensitivity of the cisplatin-resistant gene STAG2. The effects of STAG2 on drug resistance and survival rates of patients with CRC were examined using the Genomics of Drug Sensitivity in Cancer (GDSC) and Kaplan-Meier (KM) plotter databases. Subsequently, a sh-STAG2-HT-29 cell line was generated using a knockdown test of STAG2, and the half-maximal inhibitory concentration (IC50) of the two cell lines was determined using a cell viability test. We then used various techniques, including the Cell Counting Kit-8 (CCK-8), plate cloning, 5-ethynyl-2'-deoxyuridine (EdU) fluorescence staining, flow cytometry for cell cycle detection, the scar assay, the Transwell invasion assay, and Annexin V-fluorescein isothiocyanate (FITC)/propidium iodide (PI) fluorescence staining for apoptosis detection, to investigate the functionality of the four subgroups of cancer cell lines. Additionally, Western blotting (WB) was used to identify the potential pathways associated with the observed functional alterations. Finally, the phenotype, tumor weight, mouse weight, tumor volume, and tumor tissue structure of the developed tumors were assessed using the subcutaneous tumor formation method. Database analysis indicated that STAG2 plays a role in facilitating drug resistance among individuals with CRC. Furthermore, mutations in this gene lead to increased sensitivity to cisplatin, and its overexpression was associated with an unfavorable prognosis. Following the successful development of STAG2 knockdown cells, differences in IC50 concentrations were observed between HT-29 and sh-STAG2-HT-29 cells. A treatment concentration of 10 μM cisplatin was selected, and the proliferation, migration, and invasion capabilities of cancer cells decreased after STAG2 knockdown. Additionally, the sensitivity of the cells to cisplatin therapy was increased, which was potentially mediated by the epithelial-mesenchymal transition (EMT) pathway. In mice, the tumorigenic potential of HT-29 cells was reduced by STAG2 knockdown, accompanied by a decrease in resistance to cisplatin therapy. STAG2 acts as a proto-oncogene in CRC, and its resistance to cisplatin therapy is more prominent. This study confirmed the role of STAG2 in CRC and provided a theoretical basis for the further development of STAG2 as an auxiliary criterion for determining dosage when patients are treated with platinum drugs.

Mycobacterium tuberculosis Drug Resistance and Evaluation of the Current Situation

Aim: We aimed to determine the antituberculosis drug susceptibility status in Mycobacterium tuberculosis complex isolates, considering that current drug resistance rates will be an important indicator of the prevalence of primary drug resistance in the future. Material and Methods: All cases whose culture sample was taken with clinical suspicion of tuberculosis at Samsun Training and Research Hospital in the period between January 2018 and December 2023 and who had a positive result in at least one of the Acid-fast stain (AFS) and culture methods were included in the study. Results: The average age of the patients was 54.5±18.5 (range: 17-93) and 398 (74.1%) were male. In the study, 77.3% of the samples were sputum and 15.8% were bronchoalveolar lavage. 474 (88.3%) of the isolates were M. tuberculosis complex. 49% of the samples were positive with the AFS method, 96.5% with Mycobacteria Growth Indicator Tube (MGIT), and 84.5% with Löwenstein-Jensen (LJ) medium. The resistance rates in the isolates were 10.6%, 2.8%, 1.1% and 7.0% for isoniazid, rifampicin, ethambutol and streptomycin, respectively. All isolates resistant to rifampicin were also resistant to isoniazid. The rate of multidrug-resistant isolates was found to be 2.8%. The single drug resistance rate was found to be 14.0%. It was determined that the resistance rates before the pandemic were significantly higher than during the pandemic period. Conclusion: The resistance rates to isoniazid and streptomycin in M. tuberculosis complex isolates were around 10% and that the general resistance rates to primary anti-tuberculosis drugs decreased significantly during the pandemic period.

Prevalence and antimicrobial susceptibility pattern of Mycobacterium abscessus complex isolates in Chongqing, Southwest China

ObjectivesTo investigate the prevalence of Mycobacterium abscessus complex (MABC), drug resistance characteristics, and the relationship between clarithromycin (CLA) susceptibility and MABC genotype in Chongqing, China. MethodsA total of 434 NTM patient isolates were collected between October 2018 and October 2019. Isolates confirmed to be non-tuberculous mycobacteria (NTM) were tested for minimal inhibitory concentrations of antimicrobial agents. In addition, rrl and erm(41) gene sequences were used to analyze the acquired macrolide resistance and inducible macrolide resistance. ResultsOverall, 17 different NTM species were detected, of which M. abscessus (22.6 %, 91/403) was most prevalent. Amikacin, CLA, azithromycin and cefoxitin exhibited potent activities against MABC organisms, but no significant differences were observed in drug resistance rates between M. abscessus and M. massiliense (P > 0.05). On day 3 of culture, the acquired resistance rate against CLA was 7.4 % (9/121). Of 41 MABC isolates with inducible CLA resistant, 95.1 % (39/41) isolates belonged to the erm(41) T28 sequevar, while the remaining 4.9 % (2/41) possessed the M. massiliense genotype. All erm(41) C28 sequevar isolates were sensitive to CLA on day3 and day 14 of culture. Meanwhile, of the 5 erm(41) T28 isolates with acquired resistance, all possessed rrl 2058/2059 mutations, including 3 isolates with A2058C mutation and 2 isolates with A2059G mutation. While 2 of the 4 M. massiliense isolates with acquired resistance possessed the A2059G mutation, and one isolate possessed the A2058G mutation. ConclusionErm(41) and rrl gene could serve as useful markers for predicting macrolide susceptibility of MABC complex isolates.

CuET overcomes regorafenib resistance by inhibiting epithelial-mesenchymal transition through suppression of the ERK pathway in hepatocellular carcinoma

Background and PurposeRegorafenib was approved by the US Food and Drug Administration (FDA) for hepatocellular carcinoma (HCC) patients showing progress on sorafenib treatment. However, there is an inevitably high rate of drug resistance associated with regorafenib, which reduces its effectiveness in clinical treatment. Thus, there is an urgent need to find a potential way to solve the problem of regorafenib resistance. The metabolite of disulfiram complexed with copper, the Diethyldithiocarbamate-copper complex (CuET), has been found to be an effective anticancer drug candidate. In the present study, we aimed to evaluate the effect of CuET on regorafenib resistance in HCC and uncover the associated mechanism. Experimental ApproachRegorafenib-resistant HCC strains were constructed by applying an increasing concentration gradient. This study employed a comprehensive range of methodologies, including the cell counting kit-8 (CCK-8) assay, colony formation assay, cell cycle analysis, wound healing assay, Transwell assay, tumor xenograft model, and immunohistochemical analysis. These methods were utilized to investigate the antitumor activity of CuET, assess the combined effect of regorafenib and CuET, and elucidate the molecular mechanism underlying CuET-mediated regorafenib resistance. Key ResultsThe inhibitory effect of regorafenib on cell survival, proliferation and migration was decreased in regorafenib-resistant MHCC-97H (MHCC-97H/REGO) cells compared with parental cells. CuET demonstrated significant inhibitory effects on cell survival, proliferation, and migration of various HCC cell lines. CuET restored the sensitivity of MHCC-97H/REGO HCC cells to regorafenib in vitro and in vivo. Mechanistically, CuET reverses regorafenib resistance in HCC by suppressing epithelial-mesenchymal transition (EMT) through inhibition of the ERK signaling pathway. Conclusion and ImplicationsTaken together, the results of this study demonstrated that CuET inhibited the activation of the ERK signaling pathway, leading to the suppression of the epithelial-mesenchymal transition (EMT) and subsequently reversing regorafenib resistance in HCC both in vivo and in vitro. This study provides a new idea and potential strategy to improve the treatment of regorafenib-resistant HCC.

Application and research progress of patient-derived organoids in the multimodality treatment of pancreatic cancer

Pancreatic cancer is one of the most malignant tumors with a 5-year survival rate of 13%. Difficulty in early diagnosis,high tumor heterogeneity,high rate of drug resistance,and lack of effective new drugs are the main reasons for the poor therapeutic effect. Traditional cell line models cannot simulate the tumor environment in vitro and cannot reflect the heterogeneity of pancreatic cancer,while animal models have a long culture process and cannot be used for high-throughput screening. Pancreatic cancer organoids can be continuously expanded and cultured in vitro,which can realistically reflect the heterogeneity of pancreatic cancer and allow high-throughput drug screening,making it an ideal tool for individualized precision diagnosis and treatment of pancreatic cancer. According to recent studies on the evaluation of clinical drug efficacy using pancreatic cancer organoids,the drug sensitivity of pancreatic cancer organoids is highly consistent with the clinical efficacy,demonstrating the feasibility of drug sensitivity of pancreatic cancer organoids in guiding clinical therapy,comfirming the ability to discover potential therapeutic drugs through high-throughput drug screening of pancreatic cancer organoids. At the same time,this review reveals the importance of pancreatic cancer organoids as a model of the pancreatic cancer microenvironment for the development of new drugs and tumor microenvironment research. and the role of pancreatic cancer organoids as a model that can reflect the specific microenvironment of pancreatic cancer for new drug discovery and microenvironmental evaluation. Pancreatic cancer organoids and organ-on-chips are powerful tools for precision companion therapy and new drug discovery.

In vitro sensitivity of Candida albicans isolates to antifungal agents and the effect of biofilms on the drug resistance rate

Background and objectives: The pathogenic species that is most frequently isolated from fungus infections is Candida albicans. The host's immune system, the severity of the infection, and the antifungal medication of choice all influence the management of these infections. Despite the advancement of novel antifungal medications, epidemiological investigations have demonstrated that resistance to antifungal agents in C. albicans strains is becoming a significant issue. The aims of this study were to (I) determine the prevalence of antifungal resistance in 53 oral Candida albicans isolates and (II) investigate the effect of biofilm production capacity on antifungal resistance rates. Methods: Fifty-three isolates of Candida albicans were evaluated for biofilm production using the Tissue Culture Plate Method (TCPM). The antifungal susceptibility pattern of these isolates for amphotericin B, caspofungin, anidulafungin, voriconazole, itraconazole, ketoconazole, and posaconazole was determined using the E-test. Results: The present study showed strong, moderate, weak, and negative biofilm production in 18.9%, 34.0%, 26.4%, and 20.8% of the C. albicans isolates, respectively. Amphotericin B, anidulafungin, and caspofungin effectively inhibited all of the tested isolates. The resistance rates of C. albicans isolates to fluconazole, itraconazole, ketoconazole, voriconazole, and posaconazole were 35.8%, 20.7%, 37.7%, 13.2%, and 20.7%, respectively. Strong and moderate biofilm-producing isolates displayed higher resistance rates compared to weak and negative biofilm producers. The majority of antifungal treatments showed a significant difference (p &lt;0.05)". Conclusion: Our results suggest that the study area has a higher prevalence of azole-resistant Candida albicans. Thus, there is an urgent need to develop a plan to decrease the overuse and unneeded adverse effects of antifungal medications. Testing for antifungal susceptibility and fungus culture will be helpful in monitoring resistance and providing therapy for patients. It was observed that the development of Candida albicans biofilms was correlated with the drug resistance component of oral Candida albicans isolates.

Candida parapsilosis candidemia in children admitted to a tertiary hospital in Turkey: clinical features and antifungal susceptibility.

It has been observed that the frequency and antifungal resistance of Candida parapsilosis have increased recently. In our study, we aimed to determine the antifungal sensitivity of C. parapsilosis and the clinical and demographic characteristics of children with candidemia. It was observed that the patients' history of malignancy, mechanical ventilation, urinary catheter, nasogastric tube, and intensive care stay was associated with C. parapsilosis mortality. The mortality rate from candidemia was 9.5%. The most frequently preferred antifungal agents were amphotericin B and fluconazole. The fluconazole drug resistance rate was found to be 6%, and the amphotericin B drug resistance rate was 4%. Because C. parapsilosis candidemia mortality rates can be high depending on risk factors and clinical characteristics, it is important to initiate appropriate and timely antifungal therapy.

Integrated analysis reveals a novel 5-fluorouracil resistance-based prognostic signature with promising implications for predicting the efficacy of chemotherapy and immunotherapy in patients with colorectal cancer.

5-Fluorouracil (5-FU) has been used as a standard first-line treatment for colorectal cancer (CRC) patients. Although 5-FU-based chemotherapy and immune checkpoint blockade (ICB) have achieved success in treating CRC, drug resistance and low response rates remain substantial limitations. Thus, it is necessary to construct a 5-FU resistance-related signature (5-FRSig) to predict patient prognosis and identify ideal patients for chemotherapy and immunotherapy. Using bulk and single-cell RNA sequencing data, we established and validated a novel 5-FRSig model using stepwise regression and multiple CRC cohorts and evaluated its associations with the prognosis, clinical features, immune status, immunotherapy, neoadjuvant therapy, and drug sensitivity of CRC patients through various bioinformatics algorithms. Unsupervised consensus clustering was performed to categorize the 5-FU resistance-related molecular subtypes of CRC. The expression levels of 5-FRSig, immune checkpoints, and immunoregulators were determined using quantitative real-time polymerase chain reaction (RT‒qPCR). Potential small-molecule agents were identified via Connectivity Map (CMap) and molecular docking. The 5-FRSig and cluster were confirmed as independent prognostic factors in CRC, as patients in the low-risk group and Cluster 1 had a better prognosis. Notably, 5-FRSig was significantly associated with 5-FU sensitivity, chemotherapy response, immune cell infiltration, immunoreactivity phenotype, immunotherapy efficiency, and drug selection. We predicted 10 potential compounds that bind to the core targets of 5-FRSig with the highest affinity. We developed a valid 5-FRSig to predict the prognosis, chemotherapeutic response, and immune status of CRC patients, thus optimizing the therapeutic benefits of chemotherapy combined with immunotherapy, which can facilitate the development of personalized treatments and novel molecular targeted therapies for patients with CRC.

Analysis of Drug Resistance Characteristics of Mycobacterium Tuberculosis in Anhui Province, 2016-2022.

To preliminarily assess the prevalence and control effect of tuberculosis and drug-resistant tuberculosis (TB) in Anhui province, and analyze the trends in the changing drug resistance spectrum of Mycobacterium tuberculosis (Mtb) isolated in Anhui province from 2016 to 2022. From 2016 to 2022, a total of 2336 culture-positive tuberculosis strains were collected from four drug resistance monitoring sites. Patient demographic information was collected and drug susceptibility testing was conducted. Among the 2336 Mycobacterium tuberculosis complex strains, 1788 (76.54%) were from male patients and 548 (23.46%) were from female patients. The majority were of Han ethnicity, from rural areas, and employed in agriculture, with 12.54% (285/2273) having diabetes. A total of 1893 (81.04%) strains were sensitive to all six anti-TB drugs tested, and 443 (18.96%) strains were resistant to at least one or more anti-TB drugs. The drug resistance rate for patients undergoing initial treatment was 16.80% (348/2071), and 35.85% (95/265) for those receiving retreatment. Among the six anti-TB drugs, the resistance rates from highest to lowest were: INH (10.55%, 236/2336), SM (8.18%, 183/2336), OFX (6.53%, 146/2336), RFP (5.95%, 133/2336), EMB (2.37%, 53/2336), KM (1.97%, 44/2336). Significant differences were observed in MDR strains across different ages, types, with or without diabetes, and geographical sources (χ2=14.895,76.534,6.032,5.109, all P<0.05). The tuberculosis prevention and control measures have controlled the drug resistance rate of Mycobacterium tuberculosis to a certain extent. However, there are still statistical differences in drug resistance rates among TB patients with different categories, age groups, regions, and diabetic diseases. Early detection and prompt treatment of patients with drug-resistant TB remain critical to controlling the spread of this disease.

Evaluation of adhesin genes and risk factors associated with urinary tract infections by drug-resistant uropathogenic Escherichia coli in North of Iran.

Uropathogenic Escherichia coli (UPEC) isolates, have a wide variety of virulence factors to promote colonization and survival in the urinary tract. This study aimed to evaluate adhesin genes, biofilm formation ability, antibiotic resistance profiles of UPEC strains, and the related risk factors in patients with UTIs caused by drug-resistant UPEC. A total of 105 UPEC isolates were evaluated for biofilm formation using 96-well microtiter plates, the presence of adhesin genes by PCR assay and the antimicrobial susceptibility pattern using the disk diffusion method. Demographic and clinical characteristics of patients were investigated to identify predisposing factors for drug-resistant isolates. Out of 105 UPEC isolates, 84.8% were positive for biofilm formation. Biofilm-producing isolates exhibited a significantly higher prevalence of fimH, kpsMTII, csgA, afa/draBC, and pap adhesin genes compared to non-biofilm-producing strains (p < 0.05). The results also revealed that 52.4% of the isolates were ESBL-producing, and 84.8% were multidrug-resistant (MDR). Further analysis of antibiotic susceptibility among ESBL-producing strains showed the highest resistance rates to ampicillin, ciprofloxacin, and trimethoprim-sulfamethoxazole. Conversely, the highest susceptibility, in addition to carbapenems, was observed for fosfomycin, amikacin, cefoxitin, and nitrofurantoin. We identified hypertension as a potential risk factor for infection with ESBL-producing UPEC strains. Our results revealed a significant rate of drug resistance among UPEC isolates obtained from UTIs in our region. This underscores the importance of monitoring the empirical use of antibiotics and identifying specific risk factors in our geographical area to guide the selection of appropriate empirical treatment for UTIs.

Candida auris induces phagocytosis, reactive oxygen species production and inflammation through TLR2, TLR4 and Dectin-1 dependent signaling in macrophages

Candida auris (C. auris) is an important fungal pathogen with high rates of transmissibility, mortality, and drug resistance. However, studies on its pathogenicity, host-pathogen interactions, and macrophage immune responses against C. auris are still limited. This study compared the immune response induced by Candida albicans and C. auris, and explored the inflammation mechanisms of macrophages induced by C. auris. Macrophages showed a lower phagocytosis rate, reactive oxygen species production, and expression of pro-inflammatory cytokines like interleukin (IL)-6, tumor necrosis factor-α and IL-1β against C. auris when compared with Candida albicans. To further study the mechanism of inflammatory response induced by C. auris, macrophages were stimulated with C. auris for different concentration and duration. The expression and secretion of IL-6, tumor necrosis factor-α and IL-1β stimulated by C. auris depended on the activation of Toll-like receptor 2 (TLR2), TLR4, Dectin-1, and downstream signaling pathways. TLR2, TLR4, and Dectin-1 participated in the recognition and phagocytosis of C. auris. Dectin-1 was the most important receptor in mediating immune response, while TLR4 was the most critical receptor in influencing the inflammatory response. Overall, the study revealed that C. auris induced a lower level of phagocytosis, production of reactive oxygen species, and expression of inflammatory factors than Candida albicans, and that TLR2, TLR4, and Dectin-1 played important roles in the induction of inflammation.