Multiplatform Analysis of Primary and Metastatic Breast Tumors from the AURORA US Network identifies microenvironment and epigenetics drivers of metastasis

Patients with metastatic breast cancer (MBC) typically have short survival times and their successful treatment represents one of most challenging aspects of patient care. This poor prognostic behavior is in part due to molecular features including increased tumor cell clonal heterogeneity, multiple drug resistance mechanisms, and alterations of the tumor microenvironment. The AURORA US Metastasis Project was established with the goal to identify molecular features specifically associated with metastasis. We therefore collected and molecularly characterized specimens from 55 metastatic breast cancer (BC) patients representing 51 primary cancers and 102 metastases. The 153 unique tumors were assayed using RNAseq, tumor/germline DNA exomes and low pass whole genome sequencing, and global DNA methylation microarrays. We found intrinsic molecular subtype differences between primary tumors and their matched metastases to be rare in triple negative breast cancer (TNBC)/Basal-like subtype tumors. Conversely, tumor subtype changes were relatively frequent in estrogen receptor positive (ER+) cancers where ~30% of Luminal A cases switched to Luminal B or HER2-enriched (HER2E) subtypes. Clonal evolution studies identified changes in expression subtype coincident with DNA clonality shifts, especially involving HER2 amplification and/or the HER2E expression subtype. We further found evidence for ER-mediated downregulation of genes involved in cell-cell adhesion in metastases. Microenvironment differences varied according to tumor subtype where ER+/Luminal metastases had lower fibroblast and endothelial cell content, while TNBC/Basal-like metastases showed a dramatic decrease in B cells and T cells. In 17% of metastatic tumors, we identified DNA hypermethylation and/or focal DNA deletions near HLA-A that were associated with its’ significantly reduced expression, and with lower immune cell infiltrates. We also identified low immune cell features in brain and liver metastases when compared to other metastatic sites, even within the same patient. These findings have direct implications for the treatment of metastatic breast cancer patients with immune- and HER2-targeting therapies and suggest potential novel therapeutic avenues for the improvement of outcomes for some patients with MBC.

Characterization of virulent Escherichia coli strains isolated from patients with urological infection

Objective. Urinary tract infections (UTIs) caused by uropathogenic Escherichia coli (UPEC) affect 150 million people annually.Purpose: Characteristics of non-hospital strains of UPEC isolated from patients with UTI in Yaroslavl in 2016– 2017.Materials and methods. Susceptibility of UPEC strains (n = 20) to antibacterials was measured by the serial dilution method; the antibiotic resistance and virulence genes, phylogroups, O-serogroups and sequence types were identified by PCR and whole genome sequencing. The virulence of the strains was studied using the model of Galleria mellonella larvae.Results. UPEC strains were classified as resistant (n = 11) and multi-drug resistant (n = 9) pathogens. Betalactamase genes blaTEM (n = 10), blaCTX-M (n = 6), class 1 integrons (n = 8), and gene cassettes dfrA17-aadA5 (n = 2), dfrA1 (n = 1) and aacA4-cmlA1 (n = 1) were identified. UPEC-virulence genetic determinants coding adhesins fimH, papG, sfaS, focG, afa/draBC, csgA, siderophores iroN, fyuA, iutA, counteracting factors of host immunity ompT, traT, toxins hlyA, cnf1, usp, capsule transporter kpsMTII, colicin cvaC, and pathogenicity islands I536, II536, III536, IV536, IIJ96 и IICFT073 were detected. Highly virulent and slightly virulent for G. mellonella larvae UPEC strains were obtained with LD50 104–105 and 106–107 CFU, respectively. The phylogroups A, B1, B2, E and F, serogroups О2, О4, О6, O9, O11, О15, О18, О25, О75 and O89, known sequence types ST14, ST58, ST69, ST73, ST93, ST127, ST131, ST-141, ST165, ST297, ST457, ST537, ST744, ST1434 and novel ST9239 and ST10102 were revealed.Conclusions. The identified genetic diversity of non-hospital UPEC strains is consistent with the observed global trend in the spread of human pathogens, which are characterized with both high virulence and multiple drug resistance. This makes possible to assess prospectively the current epidemiological situation, give a forecast for its development in the future, as well as determine the optimal therapeutic options.

Impact of host factors on susceptibility to antifungal agents

An obstacle to drug development, particularly in this era of multiple drug resistance, is the under-appreciation for the role the host environment plays in microbial response to drugs. With the rise in fungal infection and drug resistance, particularly in individuals with co-morbidities, the influence serum and its components have on antimicrobial susceptibility requires assessment. This study examined the impact of physiologically relevant glucose and insulin levels in the presence and absence of 50 % human plasma on MICs for clinical isolates of Candida lusitaniae, Candida parapsilosis, Candida albicans, Candida tropicalis, Candida glabrata, Candida krusei and Cryptococcus neoformans. The addition of insulin or glucose at physiologic levels in RPMI medium alone altered the MIC in either a positive or negative fashion, depending on the organisms and drug tested, with C. glabrata most significantly altered with a 40, >32- and 46-fold increase in MIC for amphotericin B, itraconazole and miconazole, respectively. The addition of candida-antibody negative plasma also affected MIC, with the addition of glucose and insulin having a tandem effect on MIC. These findings indicate that phenotypic resistance of Candida and Cryptococcus can vary depending on the presence of insulin with glucose and plasma. This modulation of resistance may help explain treatment failures in the diabetic population and facilitate the development of stable drug-resistant strains. Furthermore, these findings indicate the need for a precision approach in the choice of drug treatment and drug development.

Bacterial Species and Antimicrobial Resistance of Clinical Isolates from Pediatric Patients in Yangon, Myanmar, 2020

Antimicrobial resistance (AMR) is a concern in medical care for children who have high burden of infectious diseases. We investigated the prevalence of bacterial species and their susceptibility to antimicrobials of 1019 clinical isolates from pediatric patients in a tertiary-care hospital in Yangon, Myanmar for one-year period (2020). The most frequently recovered species was Escherichia coli, followed by Klebsiella pneumoniae and Staphylococcus aureus, all of which accounted for 43% of clinical isolates, while 25% of isolates comprised non-fermenter, including Pseudomonas sp. and Acinetobacter sp. Phenotypically determined ESBL (extended-spectrum beta-lactamase)-positive rates in E. coli, K. pneumoniae, and Enterobacter sp. were 82%, 88%, and 65%, respectively. High rates of multiple drug resistance were noted for E. coli (84%), K. pneumoniae (81%), and Acinetobacter sp. (65%), associated with carbapenem resistance in 48%, 42%, and 59% of isolates, respectively. In contrast, S. aureus isolates exhibited low resistance rates (<30%) to most of antimicrobials, with 22% being resistant to oxacillin/cefoxitin. Fluoroquinolone resistance was found in most of bacterial species with different prevalence rates. The present study revealed the current status on prevalence of bacterial species causing infections in pediatric patients in Myanmar, highlighting the significance to monitor AMR among children.

Fluconazole and Curcumin Loaded Nanoemulsion Against Multiple Drug Resistance Dermatophytes

Purpose: Topical nanoemulsion comprising of fluconazole and curcumin was developed to target multiple drug resistance dermatophytes infection and to facilitate cutaneous delivery of these poorly water soluble drugs. Methods: Almond oil, sesame oil and paraffin light were used to formulate nanoemulsions and screened for the stability. The solubility of fluconazole and curcumin in surfactants, co-surfactants and oils was screened to decide the various components of the nanoemulsion. The oil phase was light paraffin whereas tween 80 and span 80 were the surfactants and ethanol was used as a co-surfactant. To identify the area of nanoemulsion existence, a pseudoternary diagram was drawn and optimum systems were developed. Drug-loading efficiency was assessed and the developed nanoemulsions were characterized for globule size, stability, robustness to dilution and pH. The optimized nanoemulsion was further evaluated for drug content, viscosity, skin permeation study (ex vivo) and assay of antifungal activity. Results: The globule size was below 200 nm and uniform for the optimized nanoemulsion formulation. It showed enhanced skin permeation (ex vivo) and better antifungal efficacy as compared to the native form of fluconazole and curcumin suspensions. Antimicrobial assay confirmed the synergistic effect of fluconazole and curcumin combination against multiple drug resistance Trychophytum rubrum and Trichophyton metagrophytes as compared to the fluconazole alone. Conclusion: The results clearly indicate an optimized delivery of fluconazole and curcumin in a synergistic way from the nanoemulsion formulation. This resulted in better penetration of these poorly soluble molecules and overall enhanced antifungal activity as compared to these drugs as such against multiple drug resistance dermatophytes.

Prevalence of multidrug-resistant extended spectrum beta-lactamase-producing Salmonella strains in commercial raw chicken meat

The incidence of extended spectrum beta-lactamase (ESBL)-producing pathogens is worrisome because it confers multiple drug resistance (MDR). Considering their serious clinical significance, the study investigated the prevalence of MDR-ESBL-producing Salmonella strains isolated from raw chicken meat in Southern Nigeria. A total of 240 raw chicken meat were sampled and the recovered Salmonella strains were characterized for MDR and ESBL-genes using Kirby Bauer disc diffusion and molecular techniques. Of the 52 confirmed Salmonellaenterica serotypes, 67.31% (35/52) were Salmonella entericasubsp. entericaserovar Typhimurium, 32.68% (17/52) were Salmonella entericasubsp. entericaserovar Enteritidis, 78.85% (41/52) were ESBL-producer and 88.45% (46/52) multidrug resistant. Ampicillin (96.15%) and gentamycin (40.39%) were the most and least antibiotics. The most prevalent MDR-ESBL-genes were bla CTX-M (92.68%), followed by bla SHV genes (68.29%) and bla TEM(31.71%). This study showed that Salmonella serotypes with high ESBL-genes and MDR were prevalent in raw chicken meat vended in southern Nigerian markets. Bangladesh J. Sci. Ind. Res.56(4), 271-284, 2021

Co-Entrapment of Sorafenib and Cisplatin Drugs and iRGD Tumour Homing Peptide by Poly[ε-caprolactone-co-(12-hydroxystearate)] Copolymer

The drug-loaded nanocarriers have overcome various challenges compared with the pure chemotherapeutic drug, such as limited bioavailability, multiple drug resistance, poor patient compliance, and adverse drug reactions, offering advantages such as protection from degradation in the blood stream, better drug solubility, and improved drug stability. One promising group of controlled and targeted drug delivery systems is polymer-based nanoparticles that can sustain the release of the active agent by diffusion and their degradation. Sorafenib is the only drug that can prolong the life of patients suffering from hepatocellular carcinoma. Cisplatin remains one of the most widely used broad-spectrum anticancer drugs for the treatment of a variety of solid tumours. Nanoformulations can exert a synergistic effect by entrapping two drugs with different modes of action, such as sorafenib and cisplatin. In our study, polymeric nanoparticles were prepared with a good production yield by an improved double emulsion solvent evaporation method using the copolymer of 12-hydroxystearic acid with ε-caprolactone (12CL), a biocatalytically synthesised biocompatible and biodegradable carrier, for the co-entrapment of sorafenib and cisplatin in nanotherapeutics. A bovine serum albumin (BSA) model compound was used to increase the cisplatin incorporation; then, it was successfully substituted by a iRGD tumour penetrating peptide that might provide a targeting function of the nanoparticles.

Detection of antibiotic resistance genes among multiple drug resistant Pseudomonas aeruginosa strains isolated from clinical sources in selected health institutions in Kwara State.

Introduction: Pseudomonas aeruginosa (P. aeruginosa) is a frequent nosocomial pathogen that causes severe diseases in many clinical and community settings. The objectives were to investigate the occurrence of multiple antibiotic resistant P. aeruginosa strains among clinical samples and to detect the presence of antibiotic resistance genes in the DNA molecules of the strains.Methods: Clinical specimens were collected aseptically from various human anatomical sites in five selected health institutions within Kwara State, Nigeria. Multiple drug resistance patterns of isolated micro-organisms to different antibiotics were determined using the Bauer Kirby disc diffusion technique. The DNA samples of the multiple resistant P. aeruginosa strains were extracted and subjected to Polymerase Chain Reaction (PCR) for resistance gene determination.Results: A total of 145 isolates were identified as P. aeruginosa from the clinical samples. Absolute resistance to ceftazidime, gentamicin and ceftriaxone was observed while low resistance to ciprofloxacin, piperacillin and imipenem was documented. The prevalence of bla VIM , ,bla CTX-M and blaTEM were 34.4 %, 46.7 % and 16.7 % respectively.Conclusion: This study has shown that there is a high occurrence of metallo â-lactamase- producing and antibiotic-resistant strains of P. aeruginosa in clinical specimens from the studied area. Keywords: Metallo â-lactamase enzyme, P. aeruginosa, clinical samples, antibiotic-resistance genes