Comparative proteomics reveals essential mechanisms for osmotolerance in Gluconacetobacter diazotrophicus

Plant growth-promoting bacteria are a promising alternative to improve agricultural sustainability. Gluconacetobacter diazotrophicus is an osmotolerant bacterium able to colonize several plant species, including sugarcane, coffee, and rice. Despite its biotechnological potential, the mechanisms controlling such osmotolerance remain unclear. The present study investigated the key mechanisms of resistance to osmotic stress in G. diazotrophicus. The molecular pathways regulated by the stress were investigated by comparative proteomics, and proteins essential for resistance were identified by knock-out mutagenesis. Proteomics analysis led to identify regulatory pathways for osmotic adjustment, de novo saturated fatty acids biosynthesis, and uptake of nutrients. The mutagenesis analysis showed that the lack of AccC protein, an essential component of de novo fatty acid biosynthesis, severely affected G. diazotrophicus resistance to osmotic stress. Additionally, knock-out mutants for nutrients uptake (Δtbdr and ΔoprB) and compatible solutes synthesis (ΔmtlK and ΔotsA) became more sensitive to osmotic stress. Together, our results identified specific genes and mechanisms regulated by osmotic stress in an osmotolerant bacterium, shedding light on the essential role of cell envelope and extracytoplasmic proteins for osmotolerance.     

Health effects of exposure to chlorination by-products in swimming pools

Concerns have been raised regarding the potential negative effects on human health of water disinfectants used in swimming pools. Among the disinfection options, the approaches using chlorine-based products have been typically preferred. Chlorine readily reacts with natural organic matter that are introduced in the water mainly through the bathers, leading to the formation of potentially harmful chlorination by-products (CBPs). The formation of CBPs is of particular concern since some have been epidemiologically associated with the development of various clinical manifestations. The higher the concentration of volatile CBPs in the water, the higher their concentration in the air above the pool, and different routes of exposure to chemicals in swimming pools (water ingestion, skin absorption, and inhalation) contribute to the individual exposome. Some CBPs may affect the respiratory and skin health of those who stay indoor for long periods, such as swimming instructors, pool staff, and competitive swimmers. Whether those who use chlorinated pools as customers, particularly children, may also be affected has been a matter of debate. In this article, we discuss the current evidence regarding the health effects of both acute and chronic exposures in different populations (work-related exposures, intensive sports, and recreational attendance) and identify the main recommendations and unmet needs for research in this area.     

Relationship between beliefs about medicines and adherence in elderly patients with cardiovascular and respiratory diseases: A cross-sectional study in Romania

ObjectivesThe aim of this study was to explore elderly patients’ beliefs about medicines in general, and specific towards their treatment and the relationship between beliefs and adherence.MethodsA cross-sectional study was performed by administering a questionnaire developed to meet the study’s objectives. Elderly patients were recruited from three different settings.Results167 patients agreed to participate to our study, having a mean age of 73 years. Patients were aware of the necessity for treatment, but they also showed concern over the potential for the adverse outcomes. Only 15% of the patients were completely accepting their treatment having high necessity and low concerns, while 40% were ambivalent, having high necessity beliefs, but also high concerns, with 89% being adherent in this group. Overall, higher adherence was significantly correlated with higher necessity and with higher necessity-concern differential.ConclusionPatients beliefs have an impact on adherence, thus patients’ concerns and necessities should be addressed in order to improve adherence and treatment outcome.Practice implicationsHigher necessity positively influenced adherence to treatment, suggesting the fact that healthcare professionals could improve patients’ adherence by outlining and educating the patients on the necessity of the treatment, while also managing patients’ concerns.     

Hypersensitivity reactions and anaphylaxis to checkpoint inhibitor–monoclonal antibodies and desensitization

ObjectiveTo review type 1 hypersensitivity reactions and anaphylaxis to checkpoint inhibitor–monoclonal antibodies and its management with drug desensitization.Data SourcesEnglish-language literature on MEDLINE regarding hypersensitivity, anaphylaxis, and checkpoint inhibitor–monoclonal antibodies.Study SelectionsReferences were selected based on relevance, novelty, robustness, and applicability.ResultsThere are well-known tissue toxicities associated to checkpoint inhibitors, but hypersensitivity reactions and anaphylaxis have been underreported. The presentation of these reactions is based on clinical phenotypes with underlying endotypes identified by specific biomarkers. Drug desensitizations have been successfully applied to checkpoint inhibitor drugs to allow patients with cancer to receive first-line therapies. This review provides current best practices for the recognition and diagnosis of hypersensitivity reactions and anaphylaxis to checkpoint inhibitors and their management using drug desensitization.ConclusionHypersensitivity reactions and anaphylaxis have been identified as potential adverse effects induced by checkpoint inhibitor–monoclonal antibodies. Drug desensitization is a safe and effective treatment option for patients who experience hypersensitivity reactions in need of these monoclonal antibodies to improve cancer outcomes.     

Comparison of inflammatory cytokine profiles in plasma of patients undergoing otorhinological surgery with propofol or isoflurane anesthesia

Objective and design

The effects of anesthetics on cytokine release in patients without comorbidities who undergo minor surgery are not well defined. We compared inflammatory cytokine profiles in adult patients undergoing minimally invasive surgery who received isoflurane or propofol anesthesia.

Methods

Thirty-four patients without comorbidities undergoing minor surgery were randomly assigned to receive an inhaled anesthetic (isoflurane; n = 16) or an intravenous anesthetic (propofol; n = 18). Blood samples were drawn before premedication and anesthesia (T1), 120 min after anesthesia induction (T2), and on the first post-operative day (T3). Plasma concentrations of interleukins (IL-) 1β, 6, 8, 10 and 12 and tumor necrosis factor (TNF)-α were measured using flow cytometry.

Results

The pro-inflammatory cytokine IL-6 was increased in the isoflurane group at T2 and T3 compared to T1 (P < 0.01). In the propofol group, IL-6 and IL-8 were significantly increased at T3 compared to T1. However, there were no significant differences in cytokine concentrations between the isoflurane and propofol groups.

Conclusion

An inflammatory response occurred earlier in patients who received an inhaled agent compared with an intravenous anesthetic, but no differences in plasma cytokine profiles were evident between isoflurane and propofol anesthesia in patients without comorbidities undergoing minimally invasive surgeries.     

Effect of new thiazolidine derivatives LPSF/GQ-02 and LPSF/GQ-16 on atherosclerotic lesions in LDL receptor-deficient mice (LDLR−/−)

BackgroundAtherosclerotic cardiovascular disease is a chronic inflammatory condition. Thiazolidinediones (TZDs) are used to enhance sensitivity to insulin and have demonstrated a protective effect over a variety of cardiovascular markers and risk factors. Controversially, the TZDs are associated with the development of heart failure. Thus, lines of research have invested in the search for new molecules in order to obtain more selective and less harmful treatment alternatives for the pathogenesis of atherosclerosis and its risk factors.MethodsAnimals were fed a diet rich in fat for 10 weeks. In the last 2 weeks, animals received either pioglitazone, LPSF/GQ-02, or LPSF/GQ-16 daily through gavage. At the end of the treatment, blood was collected for biochemical analysis and the aortas were dissected for subsequent analyses.ResultsNo changes in the blood lipid profile were found following the use of the drugs in comparison to the control. However, the new thiazolidine derivatives were more efficient in improving insulin resistance in comparison to pioglitazone and the control group. Morphometric analyses revealed that neither pioglitazone nor LPSF/GQ16 led to satisfactory effects over atherosclerosis. However, LPSF/GQ-02 led to a reduction in area of the atherosclerotic lesions. Ultrastructural analyses revealed extensive degeneration of the endothelium and an increase in apoptotic cells in the subendothelial space following the use of pioglitazone and LPSF/GQ-16. However, LPSF/GQ-02 caused minimal cell alterations in the aortic endothelium. Regarding markers, endothelial nitric oxide synthase (eNOS) and matrix metalloproteinase 9 (MMP-9), LPSF/GQ-16, and pioglitazone exerted similar effects, increasing the expression of MMP-9, and had no effect on the expression of eNOS compared with the control group. On the other hand, LPSF/GQ-02 was effective in reducing the expression of MMP-9 and increased eNOS significantly.ConclusionsThe results suggest that the new thiazolidine derivative LPSF/GQ-02 is a promising candidate for the treatment of atherosclerosis.     

Dengue nonstructural protein-1 status is not associated to circulating levels of interleukin-17, C-reactive protein and complement in children with acute dengue

BackgroundDuring dengue infection increase in plasma level of various substances have been reported. Some of those molecules are related to the virus biology and others result of the interaction virus–host. Nonstructural protein-1 (NS1) secreted by dengue virus has been reported to have a role in dengue pathogenesis. NS1 is capable of interacting with complement to evade viral clearance. However, there is little information about the presence of serum NS1 and the levels of other molecules related to dengue pathogenesis.ObjectivesThe aim of this study was to determine the association of the NS1 status and the circulating levels of interleukin-17 (IL-17), C-reactive protein (CRP), C3 and C4 in acute dengue.Study designIn this study the serum presence of NS1, IL-17, CRP, C3 and C4 was determined in children with acute dengue. IL-17, CRP, anti dengue-IgG content was measured by ELISA, C3 and C4 levels by an immunoturbidimetric assay and NS1 by an immunochromatographic assay.ResultsAll patients were positive for dengue infection as shown by antibodies anti-dengue and/or virus isolation. Increased levels of IL-17, CRP and C4 no related to the presence of NS1 were found in the patients. Values of C3 remained similar to controls.ConclusionsThese findings suggest that NS1 does not module the production of studied molecules during dengue infection.