Antibacterial Efficacy of Liposomal Formulations Containing Tobramycin and N-Acetylcysteine against Tobramycin-Resistant Escherichia coli, Klebsiella pneumoniae, and Acinetobacter baumannii

The antibacterial activity and biofilm reduction capability of liposome formulations encapsulating tobramycin (TL), and Tobramycin-N-acetylcysteine (TNL) were tested against tobramycin-resistant strains of E. coli, K. pneumoniae and A. baumannii in the presence of several resistant genes. All antibacterial activity were assessed against tobramycin-resistant bacterial clinical isolate strains, which were fully characterized by whole-genome sequencing (WGS). All isolates acquired one or more of AMEs genes, efflux pump genes, OMP genes, and biofilm formation genes. TL formulation inhibited the growth of EC_089 and KP_002 isolates from 64 mg/L and 1024 mg/L to 8 mg/L. TNL formulation reduced the MIC of the same isolates to 16 mg/L. TNL formulation was the only effective formulation against all A. baumannii strains compared with TL and conventional tobramycin (in the plektonic environment). Biofilm reduction was significantly observed when TL and TNL formulations were used against E. coli and K. pneumoniae strains. TNL formulation reduced biofilm formation at a low concentration of 16 mg/L compared with TL and conventional tobramycin. In conclusion, TL and TNL formulations particularly need to be tested on animal models, where they may pave the way to considering drug delivery for the treatment of serious infectious diseases.

The Profile of MicroRNA Expression and Potential Role in the Regulation of Drug-Resistant Genes in Cisplatin- and Paclitaxel-Resistant Ovarian Cancer Cell Lines

Ovarian cancer is the most lethal gynecological malignancy. The high mortality results from late diagnosis and the development of drug resistance. Drug resistance results from changes in the expression of different drug-resistance genes that may be regulated miRNA. The main aim of our study was to detect changes in miRNA expression levels in two cisplatin (CIS) and two paclitaxel (PAC)—resistant variants of the A2780 drug-sensitive ovarian cancer cell line—by miRNA microarray. The next goal was to identify miRNAs responsible for the regulation of drug-resistance genes. We observed changes in the expression of 46 miRNA that may be related to drug resistance. The overexpression of miR-125b-5p, miR-99a-5p, miR-296-3p, and miR-887-3p and downregulation of miR-218-5p, miR-221-3p, and miR-222-3p was observed in both CIS-resistant cell lines. In both PAC-resistant cell lines, we observed the upregulation of miR-221-3p, miR-222-3p, and miR-4485, and decreased expression of miR-551b-3p, miR-551b-5p, and miR-218-5p. Analysis of targets suggest that expression of important drug-resistant genes like protein Tyrosine Phosphatase Receptor Type K (PTPRK), receptor tyrosine kinase—EPHA7, Semaphorin 3A (SEMA3A), or the ATP-binding cassette subfamily B member 1 gene (ABCB1) can be regulated by miRNA.

HIV and Malaria co-infection and the impact of viral load and HAART usage on the development of Plasmodium falciparum Artemisinin and Lumefantrine resistant genes in Nnewi, Anambra State, Nigeria

Background: Human Immunodeficiency virus (HIV) and malaria co-infection poses a serious health threat in sub-Saharan Africa and other endemic countries. Highly active anti-retroviral therapy (HAART) is currently used to suppress viral loads. Methods: Blood samples collected from 400 participants comprising 200 HIV sero-positive and 200 sero-negative individuals was added to EDTA sample containers. Malaria parasitemia was evaluated using standard parasitological techniques followed by PCR techniques using the Quick Load One Taq One Step Polymerase Chain Reaction (PCR) for characterization of species of Plasmodium and resistant studies using specific primers. HIV viral load estimation was done using COBAS® TaqMan® Analyzer. Results: Malaria has prevalent rate of 22.75% in the study population, while the prevalence of malaria infection among the HIV sero-positive and sero-negative is 77.0% and 23% respectively. Socio-demographic factors had no significant association with the development of resistant genes. HAART exposed individuals had prevalence of PfK13 (6.9%) and Pfmdr-1 (20.8%). Viral load was significantly related with the development of resistant genes (100%) and (86.1%) for PfK13 and Pfmdr-1 respectively. Conclusion: Unsuppressed viral load in HIV sero-positive individuals heightens the prevalence of malaria parasitaemia and increases the chances of possible emergence and spread of PfK13 and Pfmdr-1 genes.

Incidence of Zonate Leaf Spot on Sorghum Accessions Under Disease-Conducive Growing Conditions Burleson County, Texa

The frequent rains coupled with cooler than normal maximum temperatures in the early part of the 2021 growing season created conditions for severe outbreaks of zonate leaf spot infection on sorghum plants in the experimental plots at the Texas A&M AgriLife Farm, Burleson County, Texas. As a result, the incidence of zonate leaf spot was recorded for 68 accessions planted in one of the field trials. In this study, 13 sorghum accessions, including TAM428, BTx635, PI330255, PI534157, PI570841, PI609251, PI570726, and PI267588 were free of zonate leaf spot infection, indicating that they were highly resistant to the disease. The lines identified in this study may possess genes for resistance which can be useful in breeding programs for introgression of the resistant genes to elite or parental lines.

In-silico genome-wide identification and characterisation of NBS-LRR gene family in banana Musa acuminata

Various common diseases caused by bacteria and viruses are increasing threats to the production of bananas worldwide. Besides the practical application of cultivation techniques, intensive exploitation of resistant genes, most of which belong to the NBS-LRR(Nucleotide-binding site - Leucine-rich repeat) gene family, in fortifying banana’s disease resistance, has been considered as a sustainable approach. The recently published genome assembly of Musa acuminata, a species of the Musa genus native to Southern Asia, has facilitated the genome-wide identification and characterisation of NBS-LRR genes. In the present study, an in-silicoapproach was employed to identify and characterise 97 NBS-LRR genes and their evolution in M. acuminatagenome. Except Ma_NBS_083 belonging to the RNLsub-family, other identified genes are members of the sub-family CNL and most of them contain only one exon. Sixty-six (66) NBS-LRR genes (68%) were mapped on 11 banana chromosomes, among them 38 genes (39%) located in clusters. Phylogenetic analysis in combination with conserved motif identification classified the banana NBS-LRR genes into seven groups. This study provides novel insight into the NBS-LRR gene family in bananas as a potential resource for further research in functional evaluation and utilisation of resistant genes.

Chromosome Mediated Fluoroquinolone and Extended Spectrum Beta-lactamase Resistant Genes in E. coli of Poultry Origin in Ekiti State

Background: One health approach aimed at solving global health crisis links human, animal, and environmental health. This inclusive strategy has contributed to antibiotic classification in both human and animal medicine. Aims: The aims of this research work are to determine the phylogenetic relationship of E. coli isolated from poultry and waste sources. The presence of chromosome mediated fluoroquinolone and extended spectrum beta-lactamase resistant genes will also be detected in the isolates. Study Design: Experimental design. Methodology: Data on farming attitudes of poultry farmers were collected using a questionnaire. E. coli was isolated from fresh poultry droppings and waste disposal sites using eosine methylene blue agar. The antibiotic sensitivity profile of the isolates was determined using the modified Kirby Bauer disc diffusion method. Phenotypic expression of fluoroquinolone (qnrS) and beta-lactamase (blaCMY) resistant traits were further detected using Polymerase Chain Reaction. The 16S rRNA gene sequencing was carried out followed by sequence alignment of E. coli genes with those from GenBank sources to determine the molecular identity of the isolates. Spearman’s correlation coefficient (rs) was run to determine the relationship between antibiotic treatment and resistant profile of the isolates. The phylogenetic relationship of the isolates was determined using Bio edit and Mega 6 software. Results: Organic poultry farming was practiced by small-scaled, peasant farmers who raised free range birds while antibiotics were widely used on farms that adopted intensive mode of farming. The percentage occurrence of E. coli from waste disposal sources was lesser than that from fresh poultry droppings. Highest percentage of antibiotic resistance to the fluoroquinolones was found while the carbapenemase recorded the lowest. Statistical analysis shows that antibiotic treatment in poultry and resistant profile of isolates to antibiotics are directly related. The percentage similarity of gene sequence with those from Gene Data Bank (≥99.29%) validates the identity of the isolates as E. coli. About, 60% of the sampled population had the qnrS gene with a band size of approximately 322 base pair. Besides, 40% of the sampled isolates possessed the blaCMY gene with a band size of approximately 460 base pair. Both genes co-existed in the chromosome of 15% of the sampled isolates sourced from poultry droppings and waste sources. Phylogenetic classification links the origin of isolates from waste disposal sources to poultry production sites. Besides, variant strains of multiple antibiotic resistant E. coli from poultry with antibiotic treatment were more diverse compared to those obtained from birds raised without antibiotics. Conclusion: The qnrS and blaCMY genes found in multiple antibiotic resistant E. coli mediated resistance to critically important antibiotics. The co-existence of these genes in variants strains of E. coli occupying different phylogenetic clusters suggests that antibiotics were widely used on the birds. Antibiotic treatment regimen in poultry may be responsible for the expression of antibiotic resistant genes found in the chromosome of the variant strains of E. coli.