Correlation of caecal microbiome endotoxins genes and intestinal immune cells in Eimeria tenella infection based on bioinformatics.

Introduction: The infection with Eimeria tenella (ET) can elicit expression of various intestinal immune cells, incite inflammation, disrupt intestinal homeostasis, and facilitate co-infection with diverse bacteria. However, the reciprocal interaction between intestinal immune cells and intestinal flora in the progression of ET-infection remains unclear. Objective: The aim of this study was to investigate the correlation between cecal microbial endotoxin (CME)-related genes and intestinal immunity in ET-infection, with subsequent identification of hub potential biomarker and immunotherapy target. Methods: Differential expression genes (DEGs) within ET-infection and hub genes related to CME were identified through GSE39602 dataset based on bioinformatic methods and Protein-protein interaction (PPI) network analysis. Moreover, immune infiltration was analyzed by CIBERSORT method. Subsequently, comprehensive functional enrichment analyses employing Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis along with Gene Ontology (GO), gene set enrichment analysis (GSEA), and gene set variation analysis (GSVA) were performed. Results: A total of 1089 DEGs and 25 hub genes were identified and CXCR4 was ultimately identified as a essential CME related potential biomarker and immunotherapy target in the ET-infection. Furthermore, activated natural killer cells, M0 macrophages, M2 macrophages, and T regulatory cells were identified as expressed intestinal immune cells. The functional enrichment analysis revealed that both DEGs and hub genes were significantly enriched in immune-related signaling pathways. Conclusion: CXCR4 was identified as a pivotal CME-related potential biomarker and immunotherapy target for expression of intestinal immune cells during ET-infection. These findings have significant implications in elucidating the intricate interplay among ET-infection, CME, and intestinal immunity.

Endotoxin Inflammatory Action on Cells by Dysregulated-Immunological-Barrier-Linked ROS-Apoptosis Mechanisms in Gut-Liver Axis.

Our study highlighted the immune changes by pro-inflammatory biomarkers in the gut-liver-axis-linked ROS-cell death mechanisms in chronic and acute inflammations when gut cells are exposed to endotoxins in patients with hepatic cirrhosis or steatosis. In duodenal tissue samples, gut immune barrier dysfunction was analyzed by pro-inflammatory biomarker expressions, oxidative stress, and cell death by flow cytometry methods. A significant innate and adaptative immune system reaction was observed as result of persistent endotoxin action in gut cells in chronic inflammation tissue samples recovered from hepatic cirrhosis with the A-B child stage. Instead, in patients with C child stage of HC, the endotoxin tolerance was installed in cells, characterized by T lymphocyte silent activation and increased Th1 cytokines expression. Interesting mechanisms of ROS-cell death were observed in chronic and acute inflammation samples when gut cells were exposed to endotoxins and immune changes in the gut-liver axis. Late apoptosis represents the chronic response to injury induction by the gut immune barrier dysfunction, oxidative stress, and liver-dysregulated barrier. Meanwhile, necrosis represents an acute and severe reply to endotoxin action on gut cells when the immune system reacts to pro-inflammatory Th1 and Th2 cytokines releasing, offering protection against PAMPs/DAMPs by monocytes and T lymphocyte activation. Flow cytometric analysis of pro-inflammatory biomarkers linked to oxidative stress-cell death mechanisms shown in our study recommends laboratory techniques in diagnostic fields.

Safety Assessment: a Comparative Analysis of Quantitative Content of Bacterial Endotoxins and Evaluation of Pyrogenicity of the Kazakhstan Vaccine QazCovid-in® against COVID-19.

We measured the levels of bacterial endotoxins in the bulk vaccine product (BVP) and finished vaccine QazCovid-in® and evaluated the effect of aluminum hydroxide (adjuvant) on the results of LAL test and pyrogenicity of samples in vivo (in rabbits receiving intravenous injection into the marginal ear vein). Administration of BVP with LPS resulted in a dose-dependent increase in body temperature in rabbits similar to that caused by LPS alone, which suggests that aluminum hydroxide in the vaccine did not affect the pyrogenic response in rabbits. Moreover, the LAL test showed that the aluminum hydroxide did not hinder LPS activity after serial dilution of samples.

Airborne antibiotic and metal resistance genes - A neglected potential risk at e-waste recycling facilities.

Heavy metal-rich environments can promote the selection of metal-resistance genes (MRGs) in bacteria, often leading to the simultaneous selection of antibiotic-resistance genes (ARGs) through a process known as co-selection. To comprehensively evaluate the biological pollutants at electronic-waste (e-waste) recycling facilities, air, soil, and river samples were collected at four distinct Swiss e-waste recycling facilities and analyzed for ARGs, MRGs, mobile genetic elements (MGEs), endotoxins, and bacterial species, with correlations drawn to heavy metal occurrence. To our knowledge, the present work marks the first attempt to quantify these bio-pollutants in the air of e-waste recycling facilities, that might pose a significant health risk to workers. Although ARG and MRG's profiles varied among the different sample types, intl1 consistently exhibited high relative abundance rates, identifying it as the predominant MGE across all sample types and facilities. These findings underscore its pivol role in driving diverse bacterial adaptations to extreme heavy metal exposure by selection and dissemination of ARGs and MRGs. All air samples exhibited consistent profiles of ARGs and MRGs, with blaTEM emerging as the predominant ARG, alongside pbrT and nccA as the most prevalent MRGs. However, one facility, engaged in batteries recycling and characterized by exceptionally high concentrations of heavy metals, showcased a more diverse resistance gene profile, suggesting that bacteria in this environment required more complex resistance mechanisms to cope with extreme metal exposure. Furthermore, this study unveiled a strong association between gram-negative bacteria and ARGs and less with MRGs. Overall, this research emphasizes the critical importance of studying biological pollutants in the air of e-waste recycling facilities to inform robust safety measures and mitigate the risk of resistance gene dissemination among workers. These findings establish a solid foundation for further investigations into the complex interplay among heavy metal exposure, bacterial adaptation, and resistance patterns in such distinctive ecosystems.

Occupational exposure to endotoxins and small cell lung cancer: a systematic review with meta-analysis.

The relationship of occupational exposure to endotoxins with different histologic subtypes of lung cancer has not been established. Our objective was to conduct a systematic review with meta-analysis to assess the effect of exposure to endotoxins on the development of small cell lung cancer (SCLC). A bibliographic search was conducted using MEDLINE, Embase, CENTRAL, and Web of Science databases until December 2022, including all cohort and/or case-control studies that examined occupational exposure to endotoxins and SCLC. Risk of bias was assessed using the U.S. Office of Health Assessment and Translation tool. A random effects model was applied, publication bias were assessed, and a sensitivity analysis was conducted. Four papers were selected for meta-analysis purposes. A total of 144 incident cases of SCLC and 897 population or hospital controls were included. Occupational exposure to endotoxins was considered for textile/leather industry and agricultural sector workers exposed to endotoxins originating from wool, cotton, or leather dust. Except for one study, all investigations were classified as having a low probability of risk of biases. The results of the meta-analysis were not statistically significant (pooled OR: 0.86; 95% CI:0.69-1.08). In addition, neither between-study heterogeneity (I2=0%;p=0.92) nor publication bias was observed (p=0.49). The results of the sensitivity analysis, after including five studies that assessed the risk of SCLC among textile industry and crop/livestock farm workers (not specifically exposed to endotoxins), showed a negative statistically non-significant association and low between-study heterogeneity (pooled OR: 0.90; 95% CI:0.79-1.02; I2=22%;p=0.23). Subjects exposed to occupational exposure to endotoxins seem to exhibit a negative association with the development of SCLC, although the results are not conclusive.

The dangerous liaisons in innate immunity involving recombinant proteins and endotoxins: Examples from the literature and the Leptospira field.

Endotoxins, also known as lipopolysaccharides (LPS), are essential components of cell walls of diderm bacteria such as Escherichia coli. LPS are microbe-associated molecular patterns that can activate pattern recognition receptors. While trying to investigate the interactions between proteins and host innate immunity, some studies using recombinant proteins expressed in E. coli reported interaction and activation of immune cells. Here, we set out to provide information on endotoxins that are highly toxic to humans and bind to numerous molecules, including recombinant proteins. We begin by outlining the history of the discovery of endotoxins, their receptors and the associated signaling pathways that confer extreme sensitivity to immune cells, acting alone or in synergy with other microbe-associated molecular patterns. We list the various places where endotoxins have been found. Additionally, we warn against the risk of data misinterpretation due to endotoxin contamination in recombinant proteins, which is difficult to estimate with the Limulus amebocyte lysate assay, and cannot be completely neutralized (e.g., treatment with polymyxin B or heating). We further illustrate our point with examples of recombinant heat-shock proteins and viral proteins from severe acute respiratory syndrome coronavirus 2, dengue and HIV, for which endotoxin contamination has eventually been shown to be responsible for the inflammatory roles previously ascribed. We also critically appraised studies on recombinant Leptospira proteins regarding their putative inflammatory roles. Finally, to avoid these issues, we propose alternatives to express recombinant proteins in nonmicrobial systems. Microbiologists wishing to undertake innate immunity studies with their favorite pathogens should be aware of these difficulties.

Production of pro-inflammatory mediators stimulated by exposure of poultry house workers to airborne dust particulates.

INTRODUCTION AND OBJECTIVE: Poultry house employees spend a significant part of their work shift being exposed to airborne particulate pollutants. The aim of this study was to assess their exposure at different stages of chicken production cycle, based on quantification of pro-inflammatory mediators (IL-1ß, IL-6, IL-8, and TNFα) in nasal lavage (NAL) samples. MATERIAL AND METHODS: The concentrations of airborne dust at 3 different stages of the production cycle (i.e. empty poultry house, with 7- and 42-day-old chickens) were stationary measured using Grimm spectrometer, as well as CIS and Button samplers. The dust collected by the latter 2 samplers was analyzed for endotoxin and (1→3)-ß-D-glucan content. NAL samples were collected from employees after their work shift to determine the pro-inflammatory mediator levels. RESULTS: The maximum particulate aerosol, endotoxin, and (1→3)-ß-D-glucan concentrations at workplaces reached the levels of 4.12 mg/m3, 45.21 ng/m3, and 56.54 ng/m3, respectively. The IL-1ß, IL-6, and IL-8 concentrations in NAL samples ranged between 0.62-18.12 pg/mL, <0.70-25.37 pg/mL, and <3.50-259.5 pg/mL, respectively. All TNFα levels were below 4 pg/mL. There were no significant differences between these cytokine concentrations in NAL samples collected at different stages of chicken breeding in either 'winter' or 'summer' seasons. CONCLUSIONS: Inhalation stimulation with poultry dust containing endotoxins and (1→3)-ß-D-glucans resulted in the production of pro-inflammatory mediators, which proves the course of immunological processes in the exposed employees that may lead to adverse effects. The use of nasal lavage fluid in the control of such exposure confirms that NAL analysis is a reliable laboratory tool for assessing the impact of poultry dust on exposed farm workers.

Pharmacologic and Genetic Downregulation of Proprotein Convertase Subtilisin/Kexin Type 9 and Survival From Sepsis.

OBJECTIVES: Treatments that prevent sepsis complications are needed. Circulating lipid and protein assemblies-lipoproteins play critical roles in clearing pathogens from the bloodstream. We investigated whether early inhibition of proprotein convertase subtilisin/kexin type 9 (PCSK9) may accelerate bloodstream clearance of immunogenic bacterial lipids and improve sepsis outcomes. DESIGN: Genetic and clinical epidemiology, and experimental models. SETTING: Human genetics cohorts, secondary analysis of a phase 3 randomized clinical trial enrolling patients with cardiovascular disease (Evaluation of Cardiovascular Outcomes After an Acute Coronary Syndrome During Treatment With Alirocumab [ODYSSEY OUTCOMES]; NCT01663402), and experimental murine models of sepsis. PATIENTS OR SUBJECTS: Nine human cohorts with sepsis (total n = 12,514) were assessed for an association between sepsis mortality and PCSK9 loss-of-function (LOF) variants. Incident or fatal sepsis rates were evaluated among 18,884 participants in a post hoc analysis of ODYSSEY OUTCOMES. C57BI/6J mice were used in Pseudomonas aeruginosa and Staphylococcus aureus bacteremia sepsis models, and in lipopolysaccharide-induced animal models. INTERVENTIONS: Observational human cohort studies used genetic PCSK9 LOF variants as instrumental variables. ODYSSEY OUTCOMES participants were randomized to alirocumab or placebo. Mice were administered alirocumab, a PCSK9 inhibitor, at 5 mg/kg or 25 mg/kg subcutaneously, or isotype-matched control, 48 hours prior to the induction of bacterial sepsis. Mice did not receive other treatments for sepsis. MEASUREMENTS AND MAIN RESULTS: Across human cohort studies, the effect estimate for 28-day mortality after sepsis diagnosis associated with genetic PCSK9 LOF was odds ratio = 0.86 (95% CI, 0.67-1.10; p = 0.24). A significant association was present in antibiotic-treated patients. In ODYSSEY OUTCOMES, sepsis frequency and mortality were infrequent and did not significantly differ by group, although both were numerically lower with alirocumab vs. placebo (relative risk of death from sepsis for alirocumab vs. placebo, 0.62; 95% CI, 0.32-1.20; p = 0.15). Mice treated with alirocumab had lower endotoxin levels and improved survival. CONCLUSIONS: PCSK9 inhibition may improve clinical outcomes in sepsis in preventive, pretreatment settings.

Barriers to the Use of Recombinant Bacterial Endotoxins Test Methods in Parenteral Drug, Vaccine and Device Safety Testing.

The Bacterial Endotoxins Test (BET) is a critical safety test that is used to detect bacterial endotoxins, which are the major contributor to fever-inducing contamination risks known as pyrogens. All parenteral therapies, including every lot of injected drugs, vaccines, medical devices, must be tested for pyrogens to ensure patient safety. Bacterial endotoxins test methods were developed as a highly sensitive detection method for bacterial endotoxins, after the discovery of a clotting cascade in horseshoe crab blood. However, horseshoe crab species are limited to some inshore coastal habitats along the Atlantic coast of the USA and others throughout Asia. Fully functional horseshoe crab clotting factors can be manufactured via recombinant protein production, and several BET methods featuring recombinant horseshoe crab proteins have now been developed for commercial use. Recombinant Bacterial Endotoxins Test (rBET) methods based on the use of recombinant Factor C (rFC) were established in the European Pharmacopoeia - however, these methods have not yet been granted compendial status in the United States Pharmacopoeia (USP). In order to facilitate dialogue between stakeholders, the Physicians Committee for Responsible Medicine hosted two virtual roundtable discussions on the perceived barriers to the use of rBET methods for US FDA requirements. Stakeholders agreed that multiple rFC-based methods have been demonstrated to have suitable analytical performance, as described in ICH Q2 on the Validation of Analytical Procedures and USP <1225> on the Validation of Compendial Procedures. United States Pharmacopoeia compendial inclusion of the rFC-based and other rBET methods was favoured, in order to reduce the additional burdens created by a lack of global harmonisation on BET testing requirements.

Novel insecticidal proteins from ferns resemble insecticidal proteins from Bacillus thuringiensis.

Lepidopterans affect crop production worldwide. The use of transgenes encoding insecticidal proteins from Bacillus thuringiensis (Bt) in crop plants is a well-established technology that enhances protection against lepidopteran larvae. Concern about widespread field-evolved resistance to Bt proteins has highlighted an urgent need for new insecticidal proteins with different modes or sites of action. We discovered a new family of insecticidal proteins from ferns. The prototype protein from Pteris species (Order Polypodiales) and variants from two other orders of ferns, Schizaeales and Ophioglossales, were effective against important lepidopteran pests of maize and soybean in diet-based assays. Transgenic maize and soybean plants producing these proteins were more resistant to insect damage than controls. We report here the crystal structure of a variant of the prototype protein to 1.98 Å resolution. Remarkably, despite being derived from plants, the structure resembles the 3-domain Cry proteins from Bt but has only two out of three of their characteristic domains, lacking the C-terminal domain which is typically required for their activities. Two of the fern proteins were effective against strains of fall armyworm that were resistant to Bt 3-domain Cry proteins Cry1Fa or Cry2A.127. This therefore represents a novel family of insecticidal proteins that have the potential to provide future tools for pest control.

Microbiome analysis of Spodoptera frugiperda (Lepidoptera, Noctuidae) larvae exposed to Bacillus thuringiensis (Bt) endotoxins.

Background: Spodoptera frugiperda (or fall armyworm, FAW) is a polyphagous pest native to Western Hemisphere and recently discovered in the Eastern Hemisphere. In Colombia, S. frugiperda is recognized as a pest of economic importance in corn. The species has genetically differentiated into two host populations named "corn" and "rice" strains. In 2012, a study made in central Colombia demonstrated that the corn strain is less susceptible to Bacillus thuringiensis (Bt) endotoxins (Cry1Ac and Cry 1Ab) than the rice strain. In this country, Bt transgenic corn has been extensively produced over the last 15 years. Since gut microbiota plays a role in the physiology and immunity of insects, and has been implicated in promoting the insecticidal activity of Bt, in this study an analysis of the interaction between Bt endotoxins and FAW gut microbiota was made. Also, the detection of endosymbionts was performed here, as they might have important implications in the biological control of a pest. Methods: The composition and diversity of microbiomes associated with larval specimens of S. frugiperda(corn strain) was investigated in a bioassay based on six treatments in the presence/absence of Bt toxins and antibiotics (Ab) through bacterial isolate analyses and by high throughput sequencing of the bacterial 16S rRNA gene. Additionally, species specific primers were used, to detect endosymbionts from gonads in S. frugiperda corn strain. Results: Firmicutes, Proteobacteria and Bacteroidota were the most dominant bacterial phyla found in S. frugiperda corn strain. No significant differences in bacteria species diversity and richness among the six treatments were found. Two species of Enterococcus spp., E. mundtii and E. casseliflavus were detected in treatments with Bt and antibiotics, suggesting that they are less susceptible to both of them. Additionally, the endosymbiont Arsenophonus was also identified on treatments in presence of Bt and antibiotics. The results obtained here are important since little knowledge exists about the gut microbiota on this pest and its interaction with Bt endotoxins. Previous studies made in Lepidoptera suggest that alteration of gut microbiota can be used to improve the management of pest populations, demonstrating the relevance of the results obtained in this work.

Product safety aspects of plant molecular farming.

Plant molecular farming (PMF) has been promoted since the 1990s as a rapid, cost-effective and (most of all) safe alternative to the cultivation of bacteria or animal cells for the production of biopharmaceutical proteins. Numerous plant species have been investigated for the production of a broad range of protein-based drug candidates. The inherent safety of these products is frequently highlighted as an advantage of PMF because plant viruses do not replicate in humans and vice versa. However, a more nuanced analysis of this principle is required when considering other pathogens because toxic compounds pose a risk even in the absence of replication. Similarly, it is necessary to assess the risks associated with the host system (e.g., the presence of toxic secondary metabolites) and the production approach (e.g., transient expression based on bacterial infiltration substantially increases the endotoxin load). This review considers the most relevant host systems in terms of their toxicity profile, including the presence of secondary metabolites, and the risks arising from the persistence of these substances after downstream processing and product purification. Similarly, we discuss a range of plant pathogens and disease vectors that can influence product safety, for example, due to the release of toxins. The ability of downstream unit operations to remove contaminants and process-related toxic impurities such as endotoxins is also addressed. This overview of plant-based production, focusing on product safety aspects, provides recommendations that will allow stakeholders to choose the most appropriate strategies for process development.

Clinical evaluation of culturable bacteria, endotoxins and lipoteichoic acid in teeth with vital normal pulp tissues.

The objective of this study was to investigate the presence of culturable bacteria, endotoxins (LPS) and lipoteichoic acid (LTA) levels in teeth with normal vital pulp (NVP) with intact crowns (IC) and those with coronal restoration (CR) limited to the enamel level. A total of 20 teeth indicated for endodontic treatment due to prosthetic reasons were selected. Samples were collected from the root canals. The levels of cultivable bacteria, LPS and LTA were assessed. Statistical analyses were performed at significance level set at 5%. None of the teeth presented microbial growth. In the IC group, the LPS levels were limited to the lowest concentration of LPS. On the contrary, higher LPS and LTA levels were detected in teeth with CR. It was concluded that teeth with NVP and IC were negative for bacteria, LPS and LTA; while teeth with CR were positive for bacterial virulence factors.

Hemoperfusion Adsorbents for Removal of Common Toxins in Liver and Kidney Failure: Recent Progress, Challenges, and Prospects.

Liver and kidney failure can lead to extensive accumulation of toxic metabolites in the blood and tissues, such as bilirubin, blood ammonia, endotoxins, cytokines, creatinine, uric acid, and urea, which aggravate the progression of the disease. Hemoperfusion can effectively adsorb and remove toxins from the blood and treat liver and kidney failure. However, the adsorption efficiency and safety of traditional hemoperfusion adsorbents are not ideal. Thus, it is urgent to develop adsorbents with good blood compatibility, as well as high adsorption and strong selective capacities, to fulfill the clinical needs. In recent years, new hemoperfusion adsorbents with improved adsorption performance and good blood compatibility have been developed. This review classifies and summarizes the recent research progress in hemoperfusion adsorbents for common blood toxins (bilirubin, blood ammonia, endotoxins, cytokines, creatinine, uric acid, and urea) produced by liver and kidney failure. The composition and structure of various toxin adsorbents, toxin adsorption performance, biocompatibility, blood safety, and the adsorption mechanisms of toxins are discussed. Based on a summary of recent studies, feasible strategies have been explored for designing and preparing hemoperfusion adsorbents to fulfill future development requirements. The trends and clinical application prospects of various toxin adsorbents are also discussed.

Bacillus thuringiensis toxin Cyt2Aa forms filamentous oligomers when exposed to lipid membranes or detergents.

The bacterium Bacillus thuringiensis (Bt) produces insecticidal proteins during the sporulation phase. These proteins are located in parasporal crystals consisting of two delta-endotoxin classes, crystal (Cry) and cytolytic (Cyt) toxins. In vitro, Cyt toxins show cytolytic activity against bacterial and a variety of insect and mammalian cells. They bind to cell membranes with unsaturated phospholipids and sphingomyelin. Although Bt and its parasporal crystals containing both Cry and Cyt toxins have been successfully used as bioinsecticides, the molecular mechanism of action of Cyt toxins is not yet fully understood. To address this, we exposed Cyt2Aa to lipid membranes and visualized membrane disruption process using cryo-electron microscopy. We observed two types of Cyt2Aa oligomers. First, Cyt2Aa forms smaller curved oligomers on the membrane surface that become linear over time, and detach when the membrane ruptures. Similar linear filamentous oligomers were also formed by Cyt2Aa in the presence of detergents without prior exposure to lipid membranes, which exhibited attenuated cytolytic activity. Furthermore, our data suggest that Cyt2Aa adopts different conformations between its monomeric and oligomeric forms. Overall, our results provide new evidence for a detergent-like mechanism of action of Cyt2Aa rather than the pore-forming model of target membrane disruption of this important class of insecticidal proteins.

Panorama da qualidade biológica da água destinada ao tratamento dialítico em pacientes sob cuidados críticos em Unidades de Terapia Intensiva / Overview of the biological quality of water intended for dialysis treatment in patients under critical care in Intensive Care Units

A incidência da lesão renal aguda caracteriza-se como evento frequente em pacientes críticos internados em Unidades de Terapia Intensiva e está associada ao aumento de mortalidade, causando grande impacto à Saúde Pública. As intercorrências clínicas são minimizadas com intervenções dialíticas, acarretando a exposição do paciente a volumes expressivos de água tratada durante a terapia renal em leito. As análises microbiológicas e de determinação de endotoxinas bacterianas em amostras de água tratada e em soluções de dialisato foram executadas em dois hospitais públicos do município de São Paulo, seguindo metodologias analíticas preconizadas em compêndios oficiais. A avaliação demonstrou que a porcentagem de resultados satisfatórios no período de 2010 a 2022 variou entre 35,2 a 100% e de 40 a 100% para as unidades hospitalares I e II para a água tratada, respectivamente; e, 100% para as soluções de dialisato para a unidade hospitalar I. A eficácia de ações delineadas pelas equipes técnicas das unidades hospitalares, na adequação da água destinada à terapia dialítica, aponta para a importância em estimular outras instituições hospitalares na padronização e implantação de melhoria contínua de seus sistemas de tratamento de água para uso em procedimento dialítico, prevenindo riscos adicionais aos pacientes expostos à terapia renal.

The incidence of acute kidney is high among critically ill patients admitted to Intensive Care Units and is associated with increased mortality, having a major impact on public health. Clinical complications are minimized with dialysis interventions, which expose patients to significant volumes of treated water during in-bed renal therapy. Microbiological analyzes and determination of bacterial endotoxins were performed on treated water samples and dialysate solutions in two public hospitals in São Paulo city, using analytical methodologies recommended in official compendia. The evaluation showed that the percentage of satisfactory results for treated water ranged from 35.2% to 100% in Hospital Unit I and from 40% to 100% in Hospital Unit II between 2010 and 2022. For dialysate solutions in Hospital Unit I, the percentage of satisfactory results was 100% during the same period. The effectiveness of actions implemented by the technical hospital teams, in adapting water for dialysis therapy, points to the importance of encouraging other hospital institutions to standardize and implement a program of continuous improvement for their water treatment systems used in dialysis procedures. This will help to prevent additional risks to patients exposed to renal therapy.

Quantitative analysis of culturable bacteria, levels of endotoxins, inflammatory mediators and substance P in teeth with symptomatic irreversible pulpitis and in teeth with vital normal pulp tissues.

AIM: To comparatively analyse the levels of culturable bacteria, endotoxins (LPS), tumour necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1ß) and substance P in teeth with symptomatic irreversible pulpitis (SIP) and vital normal pulp (VNP) tissues. METHODOLOGY: Thirty-two patients were included (20 teeth with SIP and 12 teeth with VNP tissues) in this cross-sectional study. Samples were collected from the full length of the root canals (microbial analysis) and periapical tissues (2 mm beyond the apex for immunological analysis), using sterile absorbent paper points. The levels of culturable bacteria (culture method), endotoxins (LAL Pyrogent 5000), TNF-α, IL-1ß and substance P (ELISA) were assessed. The Mann-Whitney test was used for comparisons between the levels of CFU/mL, LPS, TNF-α, IL-1ß and substance P in the SIP and VNP groups. The statistical analysis was performed with the significance level set at 5%. RESULTS: Culturable bacteria were recovered from all teeth with SIP. On the other hand, no positive cultures were observed in the VNP tissues group (p > .05). The levels of LPS were approximately four times higher in teeth with SIP than in teeth with VNP tissues (p < .05). Higher levels of TNF-α and substance P were detected in teeth with SIP (p < .05). On the other hand, no difference in the levels of IL-1ß was detected between the two groups (p > .05). CONCLUSION: Teeth with symptomatic irreversible pulpitis present higher levels of culturable bacteria, endotoxins, TNF-α and substance P than those with vital normal pulp tissues. On the other hand, the levels of IL-1ß were similar in teeth from both groups suggesting reduced implications of this inflammatory mediator in the early stages of infection.

New native Bacillus thuringiensis strains induce high insecticidal action against Culex pipiens pallens larvae and adults.

Mosquitoes of many species are key disease vectors, killing millions of people each year. Bacillus thuringiensis-based insecticide formulations are largely recognized as among the most effective, ecologically safe, and long-lasting methods of managing insect pests. New B. thuringiensis strains with high mosquito control effectiveness were isolated, identified, genetically defined, and physiologically characterized. Eight B. thuringiensis strains were identified and shown to carry endotoxin-producing genes. Using a scanning electron microscope, results revealed typical crystal forms of various shapes in B. thuringiensis strains. Fourteen cry and cyt genes were found in the strains examined. Although the genome of the B. thuringiensis A4 strain had twelve cry and cyt genes, not all of them were expressed, and only a few protein profiles were observed. The larvicidal activity of the eight B. thuringiensis strains was found to be positive (LC50: 1.4-28.5 g/ml and LC95: 15.3-130.3 g/ml). Bioassays in a laboratory environment demonstrated that preparations containing B. thuringiensis spores and crystals were particularly active to mosquito larvae and adults. These new findings show that the novel preparation containing B. thuringiensis A4 spores and crystals mixture might be used to control larval and adult mosquitoes in a sustainable and ecologically friendly manner.

Toll-like receptor-4 activation by subgingival biofilm and periodontal treatment response.

OBJECTIVES: This study aims to investigate longitudinally the activation of Toll-like receptor-4 (TLR-4) by subgingival biofilm samples before and after nonsurgical periodontal therapy (NSPT). MATERIALS AND METHODS: Forty periodontitis patients received NSPT and were reviewed 3 and 6 months post-treatment. Subgingival biofilm was sampled from 4 teeth per patient, at baseline and each follow-up time point. TLR-4 activation was determined using the HEK-BLUE™/hTLR4 system. Changes in TLR-4 activation and probing pocket depths (PPDs) were evaluated using generalised linear models, and the association between TLR-4 activation and pocket reduction (defined as 6-month PPDs ≤ 3mm) was determined using generalised estimating equations. RESULTS: At 6 months, the mean TLR-4 activation by subgingival biofilm samples was significantly reduced from 11.2AU (95%CI 7.1AU, 15.4AU) to 3.6AU (95%CI 2.3AU, 4.8AU, p < 0.001), paralleling significant reductions in mean PPDs at sampled sites. The response to NSPT was associated with longitudinal TLR-4 activation profiles, with significantly higher TLR-4 activation by subgingival biofilm obtained from sites that did not achieve pocket reduction, compared to sites at which pocket reduction was achieved. CONCLUSIONS: The activation of TLR-4 by subgingival biofilm samples was reduced after NSPT, and this reduction was significantly associated with the clinical improvements (PPD reductions) at sampled sites. CLINICAL RELEVANCE: This study demonstrated an association between the longitudinal profile of TLR-4 activation by subgingival biofilm and periodontal treatment response. Longitudinal monitoring of TLR-4 activation by subgingival biofilm may potentially identify non-responsive sites, enabling targeted additional treatment.

Exposure Characterization of Wood Dust Particulate, Endotoxins, and (1-3)-ß-d-Glucans, and Their Determinants in Mozambiquan Wood Processing Workers.

OBJECTIVES: Dust generated from wood processing comprises a heterogeneous mixture of inorganic and organic particles, including wood fragments, microorganisms, endotoxins, (1-3)-ß-d-glucans, and allergens. This study characterized exposure to wood dust and its determinants in the Mozambiquan wood processing industry. METHODS: A total of 124 personal inhalable samples, collected from a stratified random sample of 30 workers, were analysed for dust particulate, endotoxins, and (1-3)-ß-d-glucans. Mixed-effects models were developed to investigate significant exposure determinants. RESULTS: The geometric mean (GM) inhalable dust particulate concentrations were 3.29 mg m-3, 98 endotoxin units (EU) m-3, and 123 ng m-3 for (1-3)-ß-d-glucans. Significant predictors for higher particulate levels included machinery (GMR = 1.93), sawing (GMR = 2.80), carpentry (GMR = 2.77), or painting (GMR = 3.03) tasks. Lebombo-ironwood species was associated with higher dust particulate levels (GMR = 1.97). Determinants of endotoxin concentrations included working with dry wood and damp cleaning methods, which were associated with lower levels. Working in closed buildings (GMR = 3.10) and dry sweeping methods were associated with higher (1-3)-ß-d-glucan concentrations (GMR = 1.99). CONCLUSIONS: Work tasks in certain exposure groups (machinery, sawing, carpentry, painting), processing certain wood species (Lebombo-ironwood) and working in closed buildings were associated with higher exposures, whilst using dry wood and damp cleaning practices reduced exposure levels.