P-glycoprotein Research Articles

Acute hepatotoxicity of intravenous amiodarone in a Becker muscular dystrophy patient with decompensated heart failing and ABCB4 gene mutation: as assessed for causality using the updated RUCAM

BackgroundCardiac dysfunction, including arrhythmias, may be one of the main clinical manifestations of Becker muscular dystrophy (BMD). Amiodarone is widely used to treat arrhythmia. However, multi-systemic toxicity caused by amiodarone, especially hepatotoxicity, should not be neglected. Here, we introduce a novel case of multi-systemic amiodarone toxicity involving the liver, renal and coagulation in BDM patient with ABCB4 gene mutation.Case presentationWe present a case of a 16-year-old boy admitted with heart failure and atrial fibrillation (AF). He was diagnosed with Becker muscular dystrophy (BMD) and gene testing showed comorbid mutations in gene DMD, ABCB4 and DSC2. Amiodarone was prescribed to control the paroxysmal atrial fibrillation intravenously. However, his liver enzyme levels were sharply elevated, along with cardiac shock, renal failure and coagulation disorders. After bedside continuous renal replacement therapy, the patient’s liver function and clinical status rehabilitated.ConclusionsABCB4 gene mutation might be involved in amiodarone-induced hepatotoxicity. Studies in a cohort might help to prove this hypothesis in the future.

Tomato bacterial wilt disease outbreaks are accompanied by an increase in soil antibiotic resistance

The presence of soil-borne disease obstacles and antibiotic resistance genes (ARGs) in soil leads to serious economic losses and health risks to humans. One area in need of attention is the evolution of ARGs as pathogenic soil gradually develops, which introduces uncertainty to the dynamic ability of conventional farming models to predict ARGs. Here, we investigated variations in tomato bacterial wilt disease accompanied by the resistome by metagenomic analysis in soils over 13 seasons of monoculture. The results showed that the abundance and diversity of ARGs and mobile genetic elements (MGEs) exhibited a significant and positive correlation with R. solanacearum. Furthermore, the binning approach indicated that fluoroquinolone (qepA), tetracycline (tetA), multidrug resistance genes (MDR, mdtA, acrB, mexB, mexE), and β-lactamases (ampC, blaGOB) carried by the pathogen itself were responsible for the increase in overall soil ARGs. The relationships between pathogens and related ARGs that might underlie the breakdown of soil ARGs were further studied in R. solanacearum invasion pot experiments. This study revealed the dynamics of soil ARGs as soil-borne diseases develop, indicating that these ecological trends can be anticipated. Overall, this study enhances our understanding of the factors driving ARGs in disease-causing soils.

Comparison of MMP-2, MMP-9, COX-2, and PGP Expression in Feline Injection-Site and Feline Noninjection-Site Sarcomas-Pilot Study.

Feline injection-site sarcomas (FISSs) are aggressive neoplasms that have been associated mostly with vaccination. Feline noninjection-site sarcomas (non-FISSs) are less frequently observed in cats and may arise in any anatomic site. This study aimed to determine the differences in the expression of the selected proteins (matrix metalloproteinase-2 (MMP-2), matrix metalloproteinase-9 (MMP-9), cyclooxygenase-2 (COX-2), and P-glycoprotein (PGP)) and their correlation with the mitotic count in FISS and non-FISS, in order to characterize their immunohistochemical features. A preliminary study of eleven samples of FISS and eight samples of non-FISS was performed using immunohistochemistry. Among all the tested sarcomas, 80.4% of the tumors were positive for COX-2, 90.2% were positive for MMP-9, and 100% were positive for PGP. The results showed that the expressions of COX-2, MMP-9, and PGP were significantly higher in FISS than in non-FISS (COX-2-p ≤ 0.001; MMP-9-p ≤ 0.05; and PGP-p ≤ 0.05). A Spearman rank correlation analysis showed a moderate negative correlation between the expression of COX-2 and MMP-9 in FISS (r = -0.52). A strong negative correlation between COX-2 and PGP (r = -0.81), a moderate positive correlation between MMP-2 and MMP-9 (r = +0.69), and a moderate negative correlation between MMP-2 and PGP (r = -0.44) were observed in non-FISS. In summary, our study presents the immunohistochemical profile of the proteins involved with inflammation and carcinogenesis in FISS and non-FISS, which can contribute to expanding the knowledge of tumor biology.

The Role of PTEN in Chemoresistance Mediated by the HIF-1α/YY1 Axis in Pediatric Acute Lymphoblastic Leukemia.

Acute lymphoblastic leukemia (ALL) is the most common childhood cancer. Current chemotherapy treatment regimens have improved survival rates to approximately 80%; however, resistance development remains the primary cause of treatment failure, affecting around 20% of cases. Some studies indicate that loss of the phosphatase and tensin homolog (PTEN) leads to deregulation of the phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt) signaling pathway, increasing the expression of proteins involved in chemoresistance. PTEN loss results in deregulation of the nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) and induces hypoxia-inducible factor 1-alpha (HIF-1α) expression in various cancers. Additionally, it triggers upregulation of the Yin Yang 1 (YY1) transcription factor, leading to chemoresistance mediated by glycoprotein p-170 (Gp-170). The aim of this study was to investigate the role of the PTEN/NF-κB axis in YY1 regulation via HIF-1α and its involvement in ALL. A PTEN inhibitor was administered in RS4;11 cells, followed by the evaluation of PTEN, NF-κB, HIF-1α, YY1, and Gp-170 expression, along with chemoresistance assessment. PTEN, HIF-1α, and YY1 expression levels were assessed in the peripheral blood mononuclear cells (PBMC) from pediatric ALL patients. The results reveal that the inhibition of PTEN activity significantly increases the expression of pAkt and NF-κB, which is consistent with the increase in the expression of HIF-1α and YY1 in RS4;11 cells. In turn, this inhibition increases the expression of the glycoprotein Gp-170, affecting doxorubicin accumulation in the cells treated with the inhibitor. Samples from pediatric ALL patients exhibit PTEN expression and higher HIF-1α and YY1 expression compared to controls. PTEN/Akt/NF-κB axis plays a critical role in the regulation of YY1 through HIF-1α, and this mechanism contributes to Gp-170-mediated chemoresistance in pediatric ALL.

High Prevalence of Antibiotic Resistance in Traditionally Fermented Foods as a Critical Risk Factor for Host Gut Antibiotic Resistome.

This study aimed to assess the suitability of fermented food interventions to replenish damaged gut microbiota. Metagenomic assessment of published sequencing data found that fermented food interventions led to a significant increase in the gut antibiotic resistome in healthy human subjects. Antibiotic resistome and viable antibiotic-resistant (AR) bacteria were further highly prevalent in retail kimchi and artisan cheeses by metagenomic and culture analyses. Representative AR pathogens of importance in nosocomial infections, such as Klebsiella pneumoniae, Serratia marcescens, and vancomycin-resistant Enterococcus (VRE), as well as commensals and lactic acid bacteria, were characterized; some exhibited an extremely high minimum inhibitory concentration (MIC) against antibiotics of clinical significance. Exposing fermented food microbiota to representative antibiotics further led to a boost of the corresponding antibiotic and multidrug-resistance gene pools, as well as disturbed microbiota, including the rise of previously undetectable pathogens. These results revealed an underestimated public health risk associated with fermented food intervention at the current stage, particularly for susceptible populations with compromised gut integrity and immune functions seeking gut microbiota rescue. The findings call for productive intervention of foodborne AR via technology innovation and strategic movements to mitigate unnecessary, massive damages to the host gut microbiota due to orally administered or biliary excreted antibiotics.

Exploring bat-inspired cyclic tryptophan diketopiperazines as ABCB1 Inhibitors

Chemotherapy-induced drug resistance remains a major cause of cancer recurrence and patient mortality. ATP binding cassette subfamily B member 1 (ABCB1) transporter overexpression in tumors contributes to resistance, yet current ABCB1 inhibitors have been unsuccessful in clinical trials. To address this challenge, we propose a new strategy using tryptophan as a lead molecule for developing ABCB1 inhibitors. Our idea stems from our studies on bat cells, as bats have low cancer incidences and high ABCB1 expression. We hypothesized that potential ABCB1 substrates in bats could act as competitive inhibitors in humans. By molecular simulations of ABCB1-substrate interactions, we generated a benzylated Cyclo-tryptophan (C3N-Dbn-Trp2) that inhibits ABCB1 activity with efficacy comparable to or better than the classical inhibitor, verapamil. C3N-Dbn-Trp2 restored chemotherapy sensitivity in drug-resistant human cancer cells with no adverse effect on cell proliferation. Our unique approach presents a promising lead toward developing effective ABCB1 inhibitors to treat drug-resistant cancers.

A comparison of antibiotic resistance genes and mobile genetic elements in wild and captive Himalayan vultures.

As the most widely distributed scavenger birds on the Qinghai-Tibetan Plateau, Himalayan vultures (Gyps himalayensis) feed on the carcasses of various wild and domestic animals, facing the dual selection pressure of pathogens and antibiotics and are suitable biological sentinel species for monitoring antibiotic resistance genes (ARGs). This study used metagenomic sequencing to comparatively investigate the ARGs and mobile genetic elements (MGEs) of wild and captive Himalayan vultures. Overall, the resistome of Himalayan vultures contained 414 ARG subtypes resistant to 20 ARG types, with abundances ranging from 0.01 to 1,493.60 ppm. The most abundant resistance type was beta-lactam (175 subtypes), followed by multidrug resistance genes with 68 subtypes. Decreases in the abundance of macrolide-lincosamide-streptogramin (MLS) resistance genes were observed in the wild group compared with the zoo group. A total of 75 genera (five phyla) of bacteria were predicted to be the hosts of ARGs in Himalayan vultures, and the clinical (102 ARGs) and high-risk ARGs (35 Rank I and 56 Rank II ARGs) were also analyzed. Among these ARGs, twenty-two clinical ARGs, nine Rank I ARG subtypes, sixteen Rank II ARG subtypes were found to differ significantly between the two groups. Five types of MGEs (128 subtypes) were found in Himalayan vultures. Plasmids (62 subtypes) and transposases (44 subtypes) were found to be the main MGE types. Efflux pump and antibiotic deactivation were the main resistance mechanisms of ARGs in Himalayan vultures. Decreases in the abundance of cellular protection were identified in wild Himalayan vultures compared with the captive Himalayan vultures. Procrustes analysis and the co-occurrence networks analysis revealed different patterns of correlations among gut microbes, ARGs, and MGEs in wild and captive Himalayan vultures. This study is the first step in describing the characterization of the ARGs in the gut of Himalayan vultures and highlights the need to pay more attention to scavenging birds.

Unveiling stem-like traits and chemoresistance mechanisms in ovarian cancer cells through the TGFβ1-PITX2A/B signaling axis.

Ovarian cancer (OC) is the deadliest gynecological malignancy, having a high mortality rate due to its asymptomatic nature, chemoresistance, and recurrence. However, the proper mechanistic knowledge behind these phenomena is still inadequate. Cancer recurrence is commonly observed due to cancer stem cells which also show chemoresistance. We aimed to decipher the molecular mechanism behind chemoresistance and stemness in OC. Earlier studies suggested that PITX2, a homeobox transcription factor and, its different isoforms are associated with OC progression upon regulating different signaling pathways. Moreover, they regulate the expression of drug efflux transporters in kidney and colon cancer, rendering chemoresistance properties in the tumor cell. Considering these backgrounds, we decided to look for the role of PITX2 isoforms in promoting stemness and chemoresistance in OC cells. In this study, PITX2A/B has been shown to promote stemness and to enhance the transcription of ABCB1. PITX2 has been discovered to augment ABCB1 gene expression by directly binding to its promoter. To further investigate the regulatory mechanism of PITX2 gene expression, we found that TGFβ signaling could augment the PITX2A/B expression through both SMAD and non-SMAD signaling pathways. Collectively, we conclude that TGFβ1-activated PITX2A/B induces stem-like features and chemoresistance properties in the OC cells.

Distinct species turnover patterns shaped the richness of antibiotic resistance genes on eight different microplastic polymers

Elucidating the formation mechanism of plastisphere antibiotic resistance genes (ARGs) on different polymers is necessary to understand the ecological risks of plastisphere ARGs. Here, we explored the turnover and assembly mechanism of plastisphere ARGs on 8 different microplastic polymers (4 biodegradable (bMPs) and 4 non-biodegradable microplastics (nMPs)) by metagenomic sequencing. Our study revealed the presence of 479 ARGs with abundance ranging from 41.37 to 58.17 copies/16S rRNA gene in all plastispheres. These ARGs were predominantly multidrug resistance genes. The richness of plastisphere ARGs on different polymers had a significant correlation with the contribution of species turnover to plastisphere ARGs β diversity. Furthermore, polymer type was the most critical factor affecting the composition of plastisphere ARGs. More opportunistic pathogens carrying diverse ARGs on BMPs (PBAT, PBS, and PHA) with higher horizontal gene transfer potential may further magnify the ecological risks and human health threats. For example, the opportunistic pathogens Riemerella anatipestifer, Vibrio campbellii, and Vibrio cholerae are closely related to human production and life, which were the important potential hosts of many plastisphere ARGs and mobile genetic elements on BMPs. Thus, we emphasize the urgency of developing the formation mechanism of plastisphere ARGs and the necessity of controlling BMPs and ARG pollution, especially BMPs, with ever-increasing usage in daily life.

Assessment of P-glycoprotein function using canine intestinal organoid-derived epithelial interfaces

P-glycoprotein (P-gp), a multidrug efflux pump encoded by the ABCB1 (formerly MDR1) gene, plays a crucial role in limiting drug absorption and eliminating toxic compounds in both humans and dogs. However, species-specific differences in P-gp substrates necessitate the development of canine-specific evaluation systems. Canine intestinal organoids derived monolayers offer a promising platform for studying drug transport, yet P-gp-mediated transport in these models remains unexplored. We generated canine colonoid-derived 2D monolayers to investigate ABCB1 gene expression and P-gp function. We employed widely recognised P-gp substrates, Rhodamine 123 and Doxorubicin, in conjunction with the P-gp inhibitor PSC833 at Days 5 and 10 of culture. A significant increase in gene expression of P-gp encoded by the ABCB1 was noted on Day 10 compared to Day 5 of culture. Despite this disparity in gene expression, the transport activity of P-gp, as assessed by the efflux of Rhodamine 123 and Doxorubicin with PSC833 inhibition, did not exhibit significant differences between these two time points. However, the inhibition of P-gp function by PSC833 confirms the presence of functional P-gp in our model. Canine intestinal organoid-derived monolayers provide a valuable tool for investigating P-gp-mediated drug transport. These findings highlight the potential for predicting drug bioavailability and adverse reactions in veterinary medicine, aligning with principles of ethical and sustainable research.

Antimicrobial resistance, biofilm formation, and molecular detection of efflux pump and biofilm genes among Klebsiella pneumoniae clinical isolates from Northern Jordan

The current study aimed to investigate the antimicrobial susceptibility profiles, biofilm production capabilities, and the prevalence of efflux pump and biofilm-associated genes among Klebsiella pneumoniae clinical isolates. One hundred sixty-seven K. pneumoniae isolates were collected from microbiology laboratories in Northern Jordan hospitals. Antimicrobial susceptibility was tested using the Kirby-Bauer method. The double-disk synergy test was used to detect the extended-spectrum beta-lactamase (ESBL) phenotype. PCR was used to detect the frequency of acrAB,tolC, and mdtk efflux pump genes and fimH-1,mrkA, and mrkD biofilm-associated genes among the isolates. The highest nonsusceptibility was observed against azithromycin (87.4 %) and nitrofurantoin (85.0 %). Among the isolates, 75.4 % and 92.2 % were multidrug resistant and produced biofilms, respectively. Efflux pump genes acrAB, tolC, and mdtK were found in 96.4 %, 95.2 %, and 90.4 % of the isolates, respectively. Biofilm-associated genes mrkD, mrkA, and fimH-1 were found in 92.2 %, 89.2 %, and 88.6 % of the isolates, respectively. The presence of the mrkA was significantly associated with biofilm formation. Overall, high percentages of multi-drug resistance, efflux pump, and biofilm-associated genes were observed among the isolates. Subsequent studies are recommended to monitor changes in the prevalence of resistance phenotypes and genotypes of isolates.

Pediatric gallstone disease—Management difficulties in clinical practice

BackgroundGallstone disease (GD) is no longer an exclusive condition of adulthood, and its prevalence is increasing in pediatric age. The management and the extent of the etiological investigation of GD in children and adolescents remains controversial. This study aimed to analyze the difficulties in the work-up and management of pediatric GD patients. MethodsA retrospective study performed in a single tertiary center enrolled sixty-five patients with GD followed from January 2014 to June 2021. Patients were categorized conveniently according to their age at diagnosis: Group A (<10years, n=35) and Group B (≥10years, n=30). We analyzed demographic, clinical and laboratory data, ultrasonographic findings at presentation, therapeutics and complications. ResultsSymptoms were more frequent in patients >10years old (p=0.001). Cholecystectomy was performed in 31 patients (47.7%). A multivariate regression logistic model identified the age >10years (OR=6.440, p=0.005) and underlying entities (OR=6.823, p=0.017) as independent variables to perform surgery. Spontaneous resolution of GD was more common in children <2years old. A multivariate regression logistic model showed a trend for those >10years old to develop more complications. Two out of 18 patients were diagnosed with ABCB4 gene mutations in heterozygosity. ConclusionsDecision-making on cholecystectomy remains challenging in asymptomatic patients. Identifying predictive factors for the development of complications has proven difficult. However, we found a trend toward the development of complications in individuals older than 10years.

Morin reverses P‐glycoprotein‐mediated multidrug‐resistance in KBChR‐8‐5 cancer cell lines

AbstractMultidrug resistance (MDR) during clinical chemotherapy for cancer has been considered a major obstacle to treatment efficacy. The involvement of adenosine triphosphate‐binding cassette (ABC) transporters in the MDR mechanism significantly reduces the efficacy of chemotherapeutics. This study investigates the potential of morin, a dietary bioflavonoid, to overcome colchicine resistance in KBChR‐8‐5 MDR cells. The P‐gp inhibitory activity by morin was measured by calcein‐AM drug efflux assay. Western blot analysis was employed to evaluate P‐gp messenger RNA and protein expressions following morin treatment. Flow cytometry analysis and acridine orange/ethidium bromide fluorescence staining were utilised to investigate the induction of apoptosis and cell cycle arrest upon treatment with morin and paclitaxel in combination. Additionally, polymerase chain reaction (PCR) array analysis was conducted to study the gene expression profiles related to MDR, apoptosis and cell cycle arrest during treatment with morin, paclitaxel or their combination. Morin exhibited a strong binding interaction with human P‐gp. This was corroborated by drug efflux assays, which showed a reduction in P‐gp efflux function with increasing morin concentration. Furthermore, morin and paclitaxel combination potentiated the induction of apoptosis and G2/M phase cell cycle arrest. Morin treatment significantly downregulated the gene expression of ABCB1 and P‐gp membrane expressions in MDR cells. Additionally, PCR array gene expression analysis revealed that the combination treatment with morin and paclitaxel upregulated proapoptotic and cell cycle arrest genes while downregulating ABCB1 gene and antiapoptotic genes. Thus, morin effectively reversed paclitaxel resistance in KBChR‐8‐5 drug‐resistant cancer cells and concluded that morin resensitized the paclitaxel resistance in KBChR8‐5 drug‐resistant cancer cells.

Plant-derived essential oil contributes to the reduction of multidrug resistance genes in the sludge composting process

Multidrug-resistant bacteria and multi-resistance genes in sludge have become a serious issue for public health. It is imperative to develop feasible and environmentally friendly methods of sludge composting to alleviate multidrug resistance genes. Plant-derived essential oil is an effective natural and eco-friendly antibacterial, which has great utilization in inhibiting pathogens in the agricultural industry. Nevertheless, the application of plant-derived essential oil to control pathogenic bacteria and antibiotic resistance in composting has not been reported. This study conducted a composting system by adding plant-derived essential oil i.e., oregano essential oil (OEO), to sludge composting. The findings indicated that multidrug resistance genes and priority pathogens (critical, high, and medium categories) were reduced by (17.0 ± 2.2)% and (26.5 ± 3.0)% in the addition of OEO (OH treatment) compared to control. Besides, the OH treatment changed the bacterial community and enhanced the gene sequences related to carbohydrate metabolism in compost microorganisms. Mantel test and variation partitioning analysis revealed that the target virulence factors (VFs), target mobile genetic elements (MGEs), and priority pathogens were the most important factors affecting multidrug resistance in composting. The OH treatment could significantly inhibit the target VFs, target MGEs, and priority pathogens, which were helpful for the suppression and elimination of multidrug resistance genes. These findings provide new insights into the regulation of multidrug resistance genes during sludge composting and a novel way to diminish the environmental risk of antibiotic resistance.

The impact of matched and mismatched donor-recipient genotypes for MDR1 polymorphisms (G2677TA, C1236T and C3435T) on the outcomes of patients after allogeneic haematopoietic stem cell transplantation.

In this study, we investigated whether matched and mismatched multidrug resistance gene (MDR1) genotypes (G2677TA, C1236T and C3435T) were associated with prognosis in patients after allogeneic haematopoietic stem cell transplantation (allo-HSCT). One hundred patients after transplantation and their donors were enrolled. Matched MDR1 G2677TA donor-recipient was associated with an increased risk of non-relapse mortality (NRM) (29.5% vs. 6.2%, p = 0.002), poor overall survival (OS) (51.7% vs. 63.8%, p = 0.024) and disease-free survival (DFS) (38.6% vs. 67%, p = 0.005). There were no differences in OS, DFS or NRM between MDR1 C1236T- and C3435T-matched and -mismatched groups. Subgroup analysis suggested that within the matched MDR1 G2677TA group, male gender, haematopoietic cell transplantation-specific comorbidity index ≥1, serum creatinine >137.2 μmol/L and post-transplantation thrombocytopenia were associated with poor survival. Our results demonstrated that patients receiving matched MDR1 G2677TA allo-HSCT experienced a poorer prognosis compared with the mismatched group. The potential mechanism may involve increased expression of P-glycoprotein, leading to decreased accumulation of antimicrobial agents and ultimately contributing to the progression of inflammation. This identification of MDR1 G2677TA genotype compatibility holds promise as a valuable molecular tool for selecting donors for allo-HSCT.

Investigation of Ivermectin Susceptibility in Kangal and Akbaş Dogs via MDR1 Gene Mutation

This research aimed to investigate the sensitivity to the drug (ivermectin) in Kangal and Akbaş breed dogs, which are dog breeds native to Turkey, via the MDR1 gene mutation. For the research, blood, hair and intraoral swap samples were taken from 30 Kangal and 20 Akbaş breed dogs (male-female mixed, adult) with ethical permission and approval forms. Kangal dog samples were taken from the dogs bred in the farms in Sivas center and Kangal village, and Akbaş dog samples were taken from the dogs bred in the farms in the Sivrihisar center, Ankara and Eskişehir regions. The samples taken were evaluated based on polymerase chain reaction (PCR) from the wool and subsequent two-way dideoxy chain termination reaction in the presence of 4 base farm deletions (c.296-299delAGAT) in the 4th exon of the ABCB1 gene that encodes the P-glycoprotein (P-gp) drug transporter protein. According to the obtained DNA sequence results, the deletion of “AGAT” was not determined in any of the individuals screened. The results of this study, which is preliminary research, showed that Kangal and Akbaş breed dogs are safe in terms of sensitivity to drugs that are set to be absorbed and excreted by the P-gp pump, especially ivermectin. However, it would be useful to repeat the analysis of both breeds with more examples.

The association between abcb1 gene polymorphism and clopidogrel response variability in stroke ischemic: a cross sectional study

BackgroundClopidogrel has been the primary choice of antiplatelet in ischemic stroke that inhibits adenosine diphosphate (ADP)-induced platelet aggregation. P-glycoprotein (P-gp) multidrug resistance-1 (MDR1) is a transmembrane efflux transporter in intestinal cells that plays a significant role in clopidogrel absorption, therefore may affect platelet aggregation. P-gp is encoded by the ABCB1 gene. This study aims to evaluate the effect of ABCB1 polymorphism on clopidogrel response variability in ischemic stroke patients and its genotype frequency.MethodsA cross-sectional study was conducted in ischemic stroke patients who received clopidogrel between 2020 and 2023 in RSUI/RSCM. All subjects were assessed for ABCB1 polymorphisms C3435T and C1236T. Platelet aggregation were measured using VerifyNow PRU. Clopidogrel response variability was classified into unresponsive (> 208 PRU), responsive (95–208 PRU), and bleeding risk (< 95 PRU).Results124 subjects enrolled in this study, with 12,9% of subjects classified as non-responsive/resistant, 49,5% as responsive, and 41,9% as bleeding risk. ABCB1 C1236T homozygote wildtype (CC) was associated with 3,76 times higher bleeding risk than other variants (p = 0,008; 95%CI 1,41 − 10,07). Genotype frequency of ABCB1 C3435T homozygote wildtype, heterozygote, and homozygote variants were 35,9%, 43,5% and 16,9%, respectively; while the genotype frequency of ABCB1 C1236T were 17,8%, 39,5%, and 42,7%, respectively.ConclusionABCB1 C1236T homozygote wildtype was associated with 3,76 times higher bleeding risk than other variants. The most common genotype frequency of ABCB1 C1236T was homozygote variant; while for ABCB1 C3435T was heterozygote.

Establishment and evaluation of a qPCR method for the detection of pfmdr1 mutations in Plasmodium falciparum, the causal agent of fatal malaria

Drug resistance surveillance is a major integral part of malaria control programs. Molecular methods play a pivotal role in drug resistance detection and related molecular research. This study aimed to develop a rapid and accurate detection method for drug resistance of Plasmodium falciparum (P. falciparum). A quantitative real-time PCR (qPCR) assay has been developed that identifies the mutation at locus A256T in the P.falciparum multi-drug resistance(pfmdr1) gene producing amino acid change at position 86. The results of 198 samples detected by qPCR were consistent with nested PCR and sequencing, giving an accuracy of 94.3%. The sensitivity, specificity, positive and negative predictive value of qPCR were 85.7%, 97.6%, 90.0% and 96.4%, respectively. The results of qPCR are basically consistent with the nested PCR, which is expected to replace the nested PCR as a new molecular biological method for drug resistance detection, providing reliable technical support for global malaria prevention and control.

Genetic characteristics of chromosomally integrated carbapenemase gene (blaNDM−1) in isolates of Proteus mirabilis

ObjectiveThis study aims to conduct an in-depth genomic analysis of a carbapenem-resistant Proteus mirabilis strain to uncover the distribution and mechanisms of its resistance genes.MethodsThe research primarily utilized whole-genome sequencing to analyze the genome of the Proteus mirabilis strain. Additionally, antibiotic susceptibility tests were conducted to evaluate the strain’s sensitivity to various antibiotics, and related case information was collected to analyze the clinical distribution characteristics of the resistant strain.ResultsStudy on bacterial strain WF3430 from a tetanus and pneumonia patient reveals resistance to multiple antibiotics due to extensive use. Whole-genome sequencing exposes a 4,045,480 bp chromosome carrying 29 antibiotic resistance genes. Two multidrug-resistant (MDR) gene regions, resembling Tn6577 and Tn6589, were identified (MDR Region 1: 64.83 Kb, MDR Region 2: 85.64 Kbp). These regions, consist of integrative and conjugative elements (ICE) structures, highlight the intricate multidrug resistance in clinical settings.ConclusionThis study found that a CR-PMI strain exhibits a unique mechanism for acquiring antimicrobial resistance genes, such as blaNDM−1, located on the chromosome instead of plasmids. According to the results, there is increasing complexity in the mechanisms of horizontal transmission of resistance, necessitating a comprehensive understanding and implementation of targeted control measures in both hospital and community settings.

Metagenomic approach revealed the mobility and co-occurrence of antibiotic resistomes between non-intensive aquaculture environment and human

BackgroundAquaculture is an important food source worldwide. The extensive use of antibiotics in intensive large-scale farms has resulted in resistance development. Non-intensive aquaculture is another aquatic feeding model that is conducive to ecological protection and closely related to the natural environment. However, the transmission of resistomes in non-intensive aquaculture has not been well characterized. Moreover, the influence of aquaculture resistomes on human health needs to be further understood. Here, metagenomic approach was employed to identify the mobility of aquaculture resistomes and estimate the potential risks to human health.ResultsThe results demonstrated that antibiotic resistance genes (ARGs) were widely present in non-intensive aquaculture systems and the multidrug type was most abundant accounting for 34%. ARGs of non-intensive aquaculture environments were mainly shaped by microbial communities accounting for 51%. Seventy-seven genera and 36 mobile genetic elements (MGEs) were significantly associated with 23 ARG types (p < 0.05) according to network analysis. Six ARGs were defined as core ARGs (top 3% most abundant with occurrence frequency > 80%) which occupied 40% of ARG abundance in fish gut samples. Seventy-one ARG-carrying contigs were identified and 75% of them carried MGEs simultaneously. The qacEdelta1 and sul1 formed a stable combination and were detected simultaneously in aquaculture environments and humans. Additionally, 475 high-quality metagenomic-assembled genomes (MAGs) were recovered and 81 MAGs carried ARGs. The multidrug and bacitracin resistance genes were the most abundant ARG types carried by MAGs. Strikingly, Fusobacterium_A (opportunistic human pathogen) carrying ARGs and MGEs were identified in both the aquaculture system and human guts, which indicated the potential risks of ARG transfer.ConclusionsThe mobility and pathogenicity of aquaculture resistomes were explored by a metagenomic approach. Given the observed co-occurrence of resistomes between the aquaculture environment and human, more stringent regulation of resistomes in non-intensive aquaculture systems may be required.4-S8N7kaEyTj6WBvQ6hX9pVideo