Lactobacillus casei suppresses hfq gene expression in Escherichia coli O157:H7

Computational prediction of new therapeutic effects of probiotics

Probiotics are living microorganisms that provide health benefits to their hosts, potentially aiding in the treatment or prevention of various diseases, including diarrhea, irritable bowel syndrome, ulcerative colitis, and Crohn's disease. Motivated by successful applications of link prediction in medical and biological networks, we applied link prediction to the probiotic-disease network to identify unreported relations. Using data from the Probio database and International Classification of Diseases-10th Revision (ICD-10) resources, we constructed a bipartite graph focused on the relationship between probiotics and diseases. We applied customized link prediction algorithms for this bipartite network, including common neighbors, Jaccard coefficient, and Adamic/Adar ranking formulas. We evaluated the results using Area under the Curve (AUC) and precision metrics. Our analysis revealed that common neighbors outperformed the other methods, with an AUC of 0.96 and precision of 0.6, indicating that basic formulas can predict at least six out of ten probable relations correctly. To support our findings, we conducted an exact search of the top 20 predictions and found six confirming papers on Google Scholar and Science Direct. Evidence suggests that Lactobacillus jensenii may provide prophylactic and therapeutic benefits for gastrointestinal diseases and that Lactobacillus acidophilus may have potential activity against urologic and female genital illnesses. Further investigation of other predictions through additional preclinical and clinical studies is recommended. Future research may focus on deploying more powerful link prediction algorithms to achieve better and more accurate results.

Engineered Extracellular Vesicles Driven by Erythrocytes Ameliorate Bacterial Sepsis by Iron Recycling, Toxin Clearing and Inflammation Regulation

Sepsis poses a significant challenge in clinical management. Effective strategies targeting iron restriction, toxin neutralization, and inflammation regulation are crucial in combating sepsis. However, a comprehensive approach simultaneously targeting these multiple processes has not been established. Here, an engineered apoptotic extracellular vesicles (apoEVs) derived from macrophages is developed and their potential as multifunctional agents for sepsis treatment is investigated. The extensive macrophage apoptosis in a Staphylococcus aureus-induced sepsis model is discovered, unexpectedly revealing a protective role for the host. Mechanistically, the protective effects are mediated by apoptotic macrophage-released apoEVs, which bound iron-containing proteins and neutralized α-toxin through interaction with membrane receptors (transferrin receptor and A disintegrin and metalloprotease 10). To further enhance therapeutic efficiency, apoEVs are engineered by incorporating mesoporous silica nanoparticles preloaded with anti-inflammatory agents (microRNA-146a). These engineered apoEVs can capture iron and neutralize α-toxin with their natural membrane while also regulating inflammation by releasing microRNA-146a in phagocytes. Moreover, to exploit the microcosmic movement and rotation capabilities, erythrocytes are utilized to drive the engineered apoEVs. The erythrocytes-driven engineered apoEVs demonstrate a high capacity for toxin and iron capture, ultimately providing protection against sepsis associated with high iron-loaded conditions. The findings establish a multifunctional agent that combines natural and engineered antibacterial strategies.

Antibacterial and antibiofilm activity of Lactobacillus strains secretome and extraction against Escherichia coli isolated from urinary tract infection

The purpose of this study was to antibacterial, and antibiofilm activity of two Lactobacillus strains secretome and extraction against E. coli isolated from women with urinary tract infection (UTI). We isolated 100 E. coli samples from women with UTI. Lactobacillus acidophilus and Lactobacillus casei characteristics were evaluated, and their secretome and extraction were prepared. The antibacterial and antibiofilm activity of secretome and extraction of both Lactobacillus strains were evaluated against isolated E. coli samples. L. acidophilus and L. casei were able to tolerate pH 3, bile salts, and pancreatic enzymes. Both probiotics were not resistant to antibiotics and demonstrated an appropriate ability to adhere to the intestinal epithelial cells. Secretome and extraction of L. acidophilus and L. casei strains showed a good antibacterial and antibiofilm against E. coli isolates. Generally, present study suggested that the secretome and extraction of L. acidophilus and L. casei strains exhibits a good antimicrobial activity.

A Comparison of the Anti-Cancer Effects of Free and PLGA-PAA Encapsulated Hydroxytyrosol on the HT-29 Colorectal Cancer Cell Line

BACKGROUND

Hydroxytyrosol is one of the phenolic compounds of olive oil and can induce anti-cancer effects on the colorectal cancer cells.

OBJECTIVE

The aim of the present study was to evaluate the free hydroxytyrosol and nano-capsulated hydroxytyrosol effects on the cell cycle arrest in HT-29 colorectal cancer cell line.

METHODS

The nano-capsulated hydroxytyrosol was synthesized in poly lactide-co-glycolide-co-polyacrylic acid (PLGA-PAA) copolymer. MTT assay was performed to evaluate the anti- proliferative and anti-tumor effects of the free hydroxytyrosol and nano-capsulated hydroxytyrosol. Finally, the relative expression of CDKN1A, CDKN1B and CCND1 genes was evaluated in the control and treated colorectal cancer cells by using Real-Time PCR.

RESULTS

The obtained results from the MTT assay showed that the cytotoxic effects of the nano-capsulated hydroxytyrosol on the colorectal cancer cell line (IC50= 6PPM) was significantly more than free hydroxytyrosol (IC50= 12PPM) after 72h. Also, nano-capsulated hydroxytyrosol showed more significant effects on the up-regulation of CDKN1A and CDKN1B genes, and down-regulation of the CCND1 gene in the colorectal cancer cells.

CONCLUSION

In conclusion, the present study showed that the hydroxytyrosol led to die the colorectal cancer cell through the cell cycle arrest. Also, the PLGA-PAA copolymer dramatically caused to increase the cytotoxic effects of the hydroxytyrosol on the colorectal cancer cells.

Anti-Cancer Effects of Probiotic Lactobacillus acidophilus for Colorectal Cancer Cell Line Caco-2 through Apoptosis Induction

Background: Colorectal cancer is one of the most common cancers worldwide. Probiotics are useful and non-pathogenic microorganisms in the gastrointestinal tract, which can show anticancer activity through the induction of apoptosis. This study aimed to evaluate the antiproliferative effects of Lactobacillus acidophilus probiotic on the Caco-2 colorectal cancer cell line. Methods: The supernatant (secreted metabolites) and bacterial extract of L. acidophilus probiotics were prepared and used as an anti-proliferative agent on the colorectal cancer cell line, Caco-2 in vitro. The effects of supernatant and extract of L. acidophilus were evaluated on the viability and proliferation of cancer cells using MTT assay. Moreover, morphological alterations of cancer cells treated with supernatant and extract of L. acidophilus were evaluated by an inverted phase contrast microscope. The mRNA expression levels of apoptosis-related genes (SURVIVIN and SMAC) in treated cancer cells and untreated controls were evaluated using the Real-Time PCR method. Results: The results showed that the supernatant and extract of L. acidophilus inhibited the viability and proliferation of cancer cells in a dose and time-dependent manner. Moreover, various morphological alterations were observed in the treated cancer cells, which are indicators of apoptosis induction. The mRNA expression of SURVIVIN and SMAC genes were significantly up-regulated and downregulated in the treated cancer cells, respectively. Conclusion: The results of the present study suggested that the supernatant and extract of L.acidophilus could inhibit the viability and proliferation of colorectal cancer cell line, Caco-2through induction of apoptosis, increase the survival rate of colon cancer patients.

Chemical Composition and Antibacterial Activities of Sumac Fruit (Rhus coriaria) Essential Oil on Dental Caries Pathogens

Introduction:

Dental caries is an infectious disease, and various microorganisms are involved in its progression. The common antibacterial agents against oral pathogens have many side effects and their excessive use cause drug resistance. Therefore, the identification of natural compounds and medicinal plants with antibacterial activity has been considered by the researchers. The Sumac (Rhus coriaria) is one of the native plants of Iran, which used as a food flavoring.

Aims & Objectives:

The aim of this study was to evaluate the antimicrobial activity of Sumac essential oil on oral pathogens, including Streptococcus mutans, Lactobacillus rhamnosus, and Actinomyces viscosus.

Materials & Methods:

In this study, the Sumac essential oil was prepared and its antibacterial activity was evaluated by disk diffusion, Minimum Inhibitory Concentration (MIC), and Minimum Bactericidal Concentration (MBC) methods on established terminology strains of S. mutans, L. rhamnosus, and A. viscosus.

Results:

The obtained results showed that the Sumac essential oil has high inhibitory effects against S. mutans, followed by L. rhamnosus and A. viscosus. The predominant compound in the Sumac essential oil was related to Beta-caryophyllene.

Conclusion:

In conclusion, Sumac essential oil has an appropriate antibacterial activity and can be used in the pharmaceutical industry to produce antibacterial agents and mouthwash, against oral infectious diseases and dental caries.

Antibiotic Resistance Pattern and Frequency of PER-1, SHV-1 and AMPC Type B-Lactamase Genes in Pseudomonas aeruginosa Isolated from Clinical Samples

Background:

The existence of Extended Spectrum B-lactamase (ESBL) genes plays an important role in spreading B-lactam antibiotic resistance in the producing strains of these enzymes. The resistance of gram-negative bacteria, such as Pseudomonas aeruginosa, to different antimicrobial agents, especially B-lactams, has increasingly been reported.

Objective:

This study was conducted to determine the prevalence of TEM-1and VEB-1 beta-lactamases gene in P. aeruginosa isolates through Polymerase Chain Reaction (PCR) method.

Methods:

100 clinical isolates of P. aeruginosa were collected from different clinical samples. The antibiotic susceptibility was examined by the disc diffusion method. The presence of PER-1, SHV-1 and AMPC genes was detected by PCR method.

Results:

Out of the studied P. aeruginosa isolates, 7, 9 and 37 isolates were positive for PER-1, SHV-1 and AMPC B-lactamases resistance genes, respectively. Patients with urinary infection had the most resistant isolates. All isolates (100%) were sensitive to polymyxin B.

Conclusion:

Antibiotic resistance in isolates of Pseudomonas can be caused by B-lactamases resistance genes. Noticing the increasing rate of the ESBLs producing strains, using the appropriate treatment protocol based on the antibiogram pattern of the strains is highly recommended.

British Journal of Biomedical Science in 2019. What have we learned?

In 2019 the British Journal of Biomedical Science published 40 articles in the various disciplines that comprise biomedical science. These were one review, 22 original articles and 17 'In Brief' short reports. Of those citing original data, the majority were in cellular pathology (14 papers), clinical chemistry (9 papers), and microbiology (6 papers: 4 in bacteriology and 2 in virology). There were 3 papers in haematology and 2 in andrology, whilst 5 papers crossed traditional discipline boundaries (such as the molecular genetics of IL6, liver function tests, and hepatocellular carcinoma). Over two-thirds of papers used techniques in molecular genetics. The present report will summarise key aspects of these publications that are of greatest relevance to laboratory scientists.