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260 result(s) for "Bacterial Lysates"
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Assessment of the Effect on Periodontitis of Antibiotic Therapy and Bacterial Lysate Treatment
Periodontitis is an inflammatory process that starts with soft tissue inflammation caused by the intervention of oral bacteria. By modulating local immunity, it is possible to supplement or replace current therapeutic methods. The aim of this study was to compare the effects of an immunostimulatory treatment with the antibiotherapy usually applied to periodontitis patients. On a model of periodontitis induced in 30 rats (divided into three equal groups) with bacterial strains selected from the human oral microbiome (Aggregatibacter actinomycetemcomitans, Fusobacterium nucleatum and Streptococcus oralis), we administered antibiotics, bacterial lysates and saline for 10 days. Clinically, no significant lesions were observed between the groups, but hematologically, we detected a decrease in lymphocyte and neutrophil counts in both the antibiotic and lysate-treated groups. Immunologically, IL-6 remained elevated compared to the saline group, denoting the body’s effort to compensate for bone loss due to bacterial action. Histopathologically, the results show more pronounced oral tissue regeneration in the antibiotic group and a reduced inflammatory reaction in the lysate group. We can conclude that the proposed bacterial lysate has similar effects to antibiotic therapy and can be considered an option in treating periodontitis, thus eliminating the unnecessary use of antibiotics.
Screening of Lipid-Reducing Activity and Cytotoxicity of the Exometabolome from Cyanobacteria
Cyanobacteria are rich producers of secondary metabolites, excreting some of these to the culture media. However, the exometabolome of cyanobacteria has been poorly studied, and few studies have dwelled on its characterization and bioactivity assessment. In this work, exometabolomes of 56 cyanobacterial strains were characterized by HR-ESI-LC-MS/MS. Cytotoxicity was assessed on two carcinoma cell lines, HepG2 and HCT116, while the reduction in lipids was tested in zebrafish larvae and in a steatosis model with fatty acid-overloaded human liver cells. The exometabolome analysis using GNPS revealed many complex clusters of unique compounds in several strains, with no identifications in public databases. Three strains reduced viability in HCT116 cells, namely Tolypotrichaceae BACA0428 (30.45%), Aphanizomenonaceae BACA0025 (40.84%), and Microchaetaceae BACA0110 (46.61%). Lipid reduction in zebrafish larvae was only observed by exposure to Dulcicalothrix sp. BACA0344 (60%). The feature-based molecular network shows that this bioactivity was highly correlated with two flavanones, a compound class described in the literature to have lipid reduction activity. The exometabolome characterization of cyanobacteria strains revealed a high chemodiversity, which supports it as a source for novel bioactive compounds, despite most of the time being overlooked.
UNAM-HIMFG Bacterial Lysate Activates the Immune Response and Inhibits Colonization of Bladder of Balb/c Mice Infected with the Uropathogenic CFT073 Escherichia coli Strain
Urinary tract infections (UTIs) represent a clinical and epidemiological problem of worldwide impact that affects the economy and the emotional state of the patient. Control of the condition is complicated due to multidrug resistance of pathogens associated with the disease. Considering the difficulty in carrying out effective treatment with antimicrobials, it is necessary to propose alternatives that improve the clinical status of the patients. With this purpose, in a previous study, the safety and immunostimulant capacity of a polyvalent lysate designated UNAM-HIMFG prepared with different bacteria isolated during a prospective study of chronic urinary tract infection (CUTI) was evaluated. In this work, using an animal model, results are presented on the immunostimulant and protective activity of the polyvalent UNAM-HIMFG lysate to define its potential use in the control and treatment of CUTI. Female Balb/c mice were infected through the urethra with Escherichia coli CFT073 (UPEC O6:K2:H1) strain; urine samples were collected before the infection and every week for up to 60 days. Once the animals were colonized, sublingual doses of UNAM-HIMFG lysate were administrated. The colonization of the bladder and kidneys was evaluated by culture, and their alterations were assessed using histopathological analysis. On the other hand, the immunostimulant activity of the compound was analyzed by qPCR of spleen mRNA. Uninfected animals receiving UNAM-HIMFG lysate and infected animals administered with the physiological saline solution were used as controls. During this study, the clinical status and evolution of the animals were evaluated. At ninety-six hours after infection, the presence of CFT073 was identified in the urine of infected animals, and then, sublingual administration of UNAM-HIMFG lysate was started every week for 60 days. The urine culture of mice treated with UNAM-HIMFG lysate showed the presence of bacteria for three weeks post-treatment; in contrast, in the untreated animals, positive cultures were observed until the 60th day of this study. The histological analysis of bladder samples from untreated animals showed the presence of chronic inflammation and bacteria in the submucosa, while tissues from mice treated with UNAM-HIMFG lysate did not show alterations. The same analysis of kidney samples of the two groups (treated and untreated) did not present alterations. Immunostimulant activity assays of UNAM-HIMFG lysate showed overexpression of TNF-α and IL-10. Results suggest that the lysate activates the expression of cytokines that inhibit the growth of inoculated bacteria and control the inflammation responsible for tissue damage. In conclusion, UNAM-HIMFG lysate is effective for the treatment and control of CUTIs without the use of antimicrobials.
Evaluation of Immunostimulatory Effects of Bacterial Lysate Proteins on THP‐1 Macrophages: Pro‐inflammatory Cytokine Response and Proteomic Profiling
Bacterial lysate proteins (BLPs) serve as potential immunostimulants, recognized by pattern recognition receptors (PRRs) on immune cells, eliciting a robust immune response. In this study, THP‐1 macrophages were treated with varying doses of BLPs derived from Streptococcus pyogenes (SP), Streptococcus agalactiae (SA), and Serratia marcescens (SM). The results showed significant increases ( p < 0.05) in pro‐inflammatory cytokines such as TNF‐ α , IL‐1 β , IL‐6, IL‐12, granulocyte macrophage‐colony stimulating factor (GM‐CSF), eotaxin, and macrophage inflammatory protein (MIP)‐1 α , except for 5 µg of all BLPs for TNF‐ α and eotaxin, and 5 µg of SP for IL‐12 production. No significant differences were found between the corresponding doses of SP and SA or SP and SM, except for GM‐CSF in all doses, while SA and SM only showed a difference at the 5 µg dose for GM‐CSF. Furthermore, there were no significant differences between the 10 and 20 µg doses of all BLPs, indicating that doses higher than 10 µg do not significantly enhance the pro‐inflammatory response. Combination doses of SP + SM and SA + SM did not show significant differences, except for IL‐1 β , suggesting no synergistic effect. Cytotoxicity was observed to increase with higher BLP concentrations in a dose‐dependent manner, with combinations of SP + SM and SA + SM exhibiting greater cytotoxicity than the individual BLPs. Proteomic analysis of BLPs identified immunostimulatory proteins, including heat shock proteins (HSPs; ClpB, DnaK, and GroEL), metabolic enzymes (glyceraldehyde 3‐phosphate dehydrogenase (GAPDH), enolase, and arginine deiminase (ADI)), and surface and secreted proteins (ESAT‐6‐like protein, CRISPR‐associated endonuclease Cas9, OmpA, porin OmpC, and serralysin), which are involved in immune modulation, bacterial clearance, and immune evasion. This study underscores the potential of bacterial proteins as vaccine adjuvants or supplementary therapies; however, further research is essential to find a balance between immune activation and inflammation reduction to develop safer and more effective immunostimulants.
Comparison of DeNovix, NanoDrop and Qubit for DNA quantification and impurity detection of bacterial DNA extracts
Accurate DNA quantification is key for downstream application including library preparations for whole genome sequencing (WGS) and the quantification of standards for quantitative PCR. Two commonly used technologies for nucleic acid quantification are based on spectrometry, such as NanoDrop, and fluorometry, such as Qubit. The DS–11+ Series spectrophotometer/fluorometer (DeNovix) is a UV spectrophotometry-based instrument and is a relatively new spectrophotometric method but has not yet been compared to established platforms. Here, we compared three DNA quantification platforms, including two UV spectrophotometry-based techniques (DeNovix and NanoDrop) and one fluorometry-based approach (Qubit). We used genomic prokaryotic DNA extracted from Streptococcus pneumoniae using a Roche DNA extraction kit. We also evaluated purity assessment and effect of a single freeze-thaw cycle. Spectrophotometry-based methods reported 3 to 4-fold higher mean DNA concentrations compared to Qubit, both before and after freezing. The ratio of DNA concentrations assessed by spectrophotometry on the one hand, and Qubit on the other hand, was function of the A 260/280 . In case DNA was pure (A 260/280 between 1.7 and 2.0), the ratio DeNovix or Nanodrop vs. Qubit was close or equal to 2, while this ratio showed an incline for DNA with increasing A 260/280 values > 2.0. The A 260/280 and A 260/230 purity ratios exhibited negligible variation across spectrophotometric methods and freezing conditions. The comparison of DNA concentrations from before and after freezing revealed no statistically significant disparities for each technique. DeNovix exhibited the highest Spearman correlation coefficient (0.999), followed by NanoDrop (0.81), and Qubit (0.77). In summary, there is no difference between DeNovix and NanoDrop in estimated gDNA concentrations of S . pneumoniae , and the spectrophotometry methods estimated close or equal to 2 times higher concentrations compared to Qubit for pure DNA.
Phagocytic activity of blood monocytes and neutrophils in moderate COVID-19 patients and impact of immune therapy with bacterial lysates
Monocytes, macrophages and dendritic cells are involved in phagocytic reactions, which potentially play an important role in the pathogenesis of COVID-19. Imbalance of these cells in peripheral blood has proven to affect not only innate but also adaptive immunity. It is possible that a search for strategies to restore monocyte activity could be a major step in achieving immune control over COVID-19. The aim of this study was to investigate the relationship between phagocytic activity of peripheral-blood monocytes and neutrophils, and COVID-19 severity, to assess the effects of a bacteria-based immunostimulating agent on phagocytosis parameters in in-hospital COVID-19 patients. The study included 105 adult patients with moderate COVID-19, who had been hospitalized in 2020-2021 and treated in accordance with the recommendations of the Ministry of Health of the Russian Federation. All patients were divided into two groups: in Group 1 patients received standard treatment and Immunovac VP4 therapeutic vaccine, a bacteria-based immunostimulating agent as add-on therapy from Day 1 of hospitalization; in Group 2 patients did not receive any add-on treatment. The study parameters included C-reactive protein (CRP), aspartate aminotransferase (AST), SpO2, lung involvement on chest computer tomography (CT) scan, and phagocytic activity of peripheral-blood leukocytes based on the absorption activity (AA) of monocytes and neutrophilic granulocytes against S. аureus). The parameters were assessed at 1, 14 and 30 days. Based on a cluster analysis of the clinical findings and the results of diagnostic tests obtained on admission, the patients were divided into 2 clusters: cluster 1 including patients with a more severe disease (n = 34) and cluster 2 including patients with a less severe disease (n = 71). Cluster 1 patients had higher levels of CRP (20.1 vs. 2.2 mg/mL, p < 0.001), AST (32.9 vs. 26.2 U/L, p = 0.003), lower SpO2 (94% vs. 96%, p < 0,001) and more extensive lung involvement on chest CT scan (35% vs. 12%, p < 0,001). There was a statistically significant direct correlation between blood monocyte AA and SpO2 (p = 0.04), an inverse correlation between monocyte AA and CRP (p = 0.003) and the extent of lung involvement on CT scan (p = 0.05). In less severe COVID-19 patients (cluster 2), no statistically significant correlation was observed. In more severe COVID-19 patients (cluster 1), there was a rise in monocyte AA on day 30 of hospitalization both in the control group (from 86.6 to 92.2, p = 0.03) and the main group, who received Immunovac VP4 add-on therapy (from 87.3 to 98.3, p = 0.05). However, the patients who received the immunostimulating agent, had higher monocyte PI than the controls, without the immunostimulant (p = 0.05). Patients from cluster 1 who were given Immunovac VP4 had higher SpO2 levels (98% vs. 97%, p = 0.01) than those who had received only the standard treatment. Blood monocyte AA correlates with COVID-19 severity: patients with less severe disease have higher AA and those with more severe illness have lower AA. The standard treatment, combined with Immunovac VP4 enhances phagocytic activity of peripheral-blood monocytes, which is associated with a more marked increase in SpO2, especially in more severe patients.
Bacterial lysates in modifying sIgA levels in the upper respiratory tract in COVID-19 patients
A great deal of evidence has accumulated suggesting an important role of mucosal immunity not only in preventing COVID-19 but also in the pathogenesis of this infection. The aim of the study was to evaluate the levels of secretory immunoglobulin A (sIgA) in different compartments of the upper respiratory tract in COVID-19 patients in relation to the severity of the disease and treatment with a bacteria-based immunomodulating agent (Immunovac VP4). The titers of sIgA were determined by ELISA in nasal epithelial swabs, pharyngeal swabs, and salivary gland secretions at baseline and on days 14 and 30 of treatment. The levels of nasal, pharyngeal and salivary sIgA were significantly lower in more severe patients (subgroup A) than in less severe patients (subgroup B), p  < 0.01. In subgroup A, the patients who received Immunovac VP4 had higher pharyngeal sIgA levels in convalescent period than those who did not receive the therapy p  < 0.05. In subgroup B patients, an increase in immunoglobulin levels was observed from baseline to day 14 of treatment whether they received the add-on therapy or not, p  < 0.01. On day 30 of treatment, the sIgA levels in the standard treatment group, however, decreased, while the patients receiving the immunomodulating agent maintained high sIgA levels, p  < 0.05. Oxygen saturation significantly increased by day 14 in both groups, p  < 0.001. However, it was higher in the Immunovac VP4 group than in the standard treatment group, p  < 0.01. Thus, addition of a bacterial lysate-based immunomodulating agent to the treatment regimen for moderate-to-severe COVID-19 induces the production of pharyngeal and salivary sIgA. SIgA production is inversely correlated to CRP levels and percentage of lung involvement on CT scan and is directly correlated to SpO 2 levels.
The Crosstalk between the Gut Microbiota Composition and the Clinical Course of Allergic Rhinitis: The Use of Probiotics, Prebiotics and Bacterial Lysates in the Treatment of Allergic Rhinitis
Although massive progress in discovering allergic rhinitis (AR) aetiology has been made in recent years, its prevalence is still rising and it significantly impacts patients’ lives. That is why further and non-conventional research elucidating the role of new factors in AR pathogenesis is needed, facilitating discoveries of new treatment approaches. One of these factors is the gut microbiota, with its specific roles in health and disease. This review presents the process of gut microbiota development, especially in early life, focusing on its impact on the immune system. It emphasizes the link between the gut microbiota composition and immune changes involved in AR development. Specifically, it elucidates the significant link between bacteria colonizing the gut and the Th1/Th2 imbalance. Probiotics, prebiotics and bacterial lysates, which are medications that restore the composition of intestinal bacteria and indirectly affect the clinical course of AR, are also discussed.
Murraya koenigii methanolic extract inhibits bacterial growth and biofilm of Staphylococcus aureus and Enterococcus faecalis
Hospital-acquired infections caused by Staphylococcus aureus and Enterococcus faecalis are significant global health challenges due to their biofilm-forming ability, also contributing to the derived antibiotic resistance and environmental persistence. This growing resistance poses serious global health challenges, emphasizing the need for better surveillance and new treatments. Plant-derived bioactives have emerged as possible therapeutics to such opportunistic pathogens and they are potential alternatives to traditional antimicrobials. This study investigates the in vitro activity of Murraya koenigii’s methanolic (MKM) leaf extract and its compounds against the growth and biofilm-forming ability of S. aureus and E. faecalis . Results revealed that the MKM extract effectively inhibited the growth of S. aureus and E. faecalis at their respective MIC levels. Furthermore, flow cytometry and confocal imaging demonstrated substantial membrane damage in MKM-treated cells compared to DMSO-treated and untreated controls. Additionally, the MKM extract significantly disrupts biofilm formation and leads to reduced extracellular polymeric substance (EPS) production. Scanning electron microscopy provided visual evidence of disrupted biofilm architecture following MKM extract treatment. HR-LC/MS analysis identified bioactive compounds within the extract, which were further evaluated for drug-likeness properties through ADME analysis. In silico molecular docking studies confirmed strong binding affinities of MKM-derived compounds with key biofilm-related receptor proteins, SpA in S. aureus and Esp in E. faecalis . These findings highlight the significant potential of MKM extract as a novel and effective phytotherapeutic resource for developing strategies to combat biofilm-associated infections.
Broncho-Vaxom Attenuates Lipopolysaccharide-Induced Inflammation in a Mouse Model of Acute Lung Injury
Acute lung injury (ALI) is a condition associated with acute respiratory failure, resulting in significant morbidity and mortality. It involves cellular changes such as disruption of the alveolar–capillary membrane, excessive neutrophil migration, and release of inflammatory mediators. Broncho-Vaxom® (BV), a lyophilized product containing cell membrane components derived from eight bacteria commonly found in the respiratory tract, is known for its potential to reduce viral and bacterial lung infections. However, the specific effect of BV on ALI has not been clearly defined. This study explored the preventive effects of BV and its underlying mechanisms in a lipopolysaccharide (LPS)-induced ALI mouse model. Oral BV (1 mg/kg) gavage was administered one hour before the intratracheal injection of LPS to evaluate its preventive effect on the ALI model. The pre-administration of BV significantly mitigates inflammatory parameters, including the production of inflammatory mediators, macrophage infiltration, and NF-κB activation in lung tissue, and the increase in inflammatory cells in bronchoalveolar lavage fluid (BALF). Moreover, BV (3 μg/mL) pretreatment reduced the expression of M1 macrophage markers, interleukins (IL-1β, IL-6), tumor necrosis factor α, and cyclooxygenase-2, which are activated by LPS, in both mouse alveolar macrophage MH-S cells and human macrophage THP-1 cells. These findings showed that BV exhibits anti-inflammatory effects by suppressing inflammatory mediators through the NF-κB pathway, suggesting its potential to attenuate bronchial and pulmonary inflammation.