To be or not to B27 positive: implications for the phenotypes of axial spondyloarthritis outcomes. Data from a large multiracial cohort from the Brazilian Registry of Spondyloarthritis.

BACKGROUND: There is a remarkable variability in the frequency of HLA-B27 positivity in patients with spondyloarthritis (SpA), which may be associated with different clinical presentations worldwide. However, there is a lack of data considering ethnicity and sex on the evaluation of the main clinical and prognostic outcomes in mixed-race populations. The aim of this study was to evaluate the frequency of HLA-B27 and its correlation with disease parameters in a large population of patients from the Brazilian Registry of Spondyloarthritis (RBE). METHODS: The RBE is a multicenter, observational, prospective cohort that enrolled patients with SpA from 46 centers representing all five geographic regions of Brazil. The inclusion criteria were as follow: (1) diagnosis of axSpA by an expert rheumatologist; (2) age ≥18 years; (3) classification according to ASAS axial. The following data were collected via a standardized protocol: demographic data, disease parameters and treatment historical. RESULTS: A total of 1096 patients were included, with 73.4% HLA-B27 positivity and a mean age of 44.4 (±13.2) years. Positive HLA-B27 was significantly associated with male sex, earlier age at disease onset and diagnosis, uveitis, and family history of SpA. Conversely, negative HLA-B27 was associated with psoriasis, higher peripheral involvement and disease activity, worse quality of life and mobility. CONCLUSIONS: Our data showed that HLA-B27 positivity was associated with a classic axSpA pattern quite similar to that of Caucasian axSpA patients around the world. Furthermore, its absence was associated with peripheral manifestations and worse outcomes, suggesting a relevant phenotypic difference in a highly miscegenated population.

Secretome of bone marrow mesenchymal stromal cells cultured in a dynamic system induces neuroprotection and modulates microglial responsiveness in an α-synuclein overexpression rat model.

BACKGROUND AIMS: Parkinson's disease (PD) is the second most common neurodegenerative disorder. The etiology of the disease remains largely unknown, but evidence have suggested that the overexpression and aggregation of alpha-synuclein (α-syn) play key roles in the pathogenesis and progression of PD. Mesenchymal stromal cells (MSCs) have been earning attention in this field, mainly due to their paracrine capacity. The bioactive molecules secreted by MSCs, i.e. their secretome, have been associated with enhanced neuronal survival as well as a strong modulatory capacity of the microenvironments where the disease develops. The selection of the appropriate animal model is crucial in studies of efficacy assessment. Given the involvement of α-syn in the pathogenesis of PD, the evidence generated from the use of animal models that develop a pathologic phenotype due to the action of this protein is extremely valuable. Therefore, in this work, we established an animal model based on the viral vector-mediated overexpression of A53T α-syn and studied the impact of the secretome of bone marrow mesenchymal stromal cells MSC(M) as a therapeutic strategy. METHODS: Adult male rats were subjected to α-syn over expression in the nigrostriatal pathway to model dopaminergic neurodegeneration. The impact of locally administered secretome treatment from MSC(M) was studied. Motor impairments were assessed throughout the study coupled with whole-region (striatum and substantia nigra) confocal microscopy evaluation of histopathological changes associated with dopaminergic neurodegeneration and glial cell reactivity. RESULTS: Ten weeks after lesion induction, the animals received secretome injections in the substantia nigra pars compacta (SNpc) and striatum (STR). The secretome used was produced from bone marrow mesenchymal stromal cells MSC(M) expanded in a spinner flask (SP) system. Nine weeks later, animals that received the viral vector containing the gene for A53T α-syn and treated with vehicle (Neurobasal-A medium) presented dopaminergic cell loss in the SNpc and denervation in the STR. The treatment with secretome significantly reduced the levels of α-syn in the SNpc and protected the dopaminergic neurons (DAn) within the SNpc and STR. CONCLUSIONS: Our results are aligned with previous studies in both α-syn Caenorhabditis elegans models, as well as 6-OHDA rodent model, revealing that secretome exerted a neuroprotective effect. Moreover, these effects were associated with a modulation of microglial reactivity supporting an immunomodulatory role for the factors contained within the secretome. This further supports the development of new studies exploring the effects and the mechanism of action of secretome from MSC(M) against α-syn-induced neurotoxicity.

Factors Associated With Mortality in Patients With Immune-Mediated Rheumatic Diseases and COVID-19 From Latin America: Data From Argentina, Mexico, and Brazil.

OBJECTIVE: To describe characteristics of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in patients with rheumatic immune-mediated inflammatory diseases (IMIDs) from Argentina, Mexico and Brazil, and to assess factors associated with mortality in this population. METHODS: Data from 3 national registries, SAR-COVID (Argentina), CMR-COVID (Mexico), and ReumaCoV-Brasil (Brazil), were combined. Adult patients with IMIDs and SARS-CoV-2 infection were recruited. Sociodemographic data, comorbidities, IMID clinical characteristics and treatment, and SARS-CoV-2 infection presentation and outcomes were recorded. RESULTS: A total of 4827 individuals were included: 2542 (52.7%) from SAR-COVID, 1167 (24.2%) from CMR-COVID, and 1118 (23.1%) from ReumaCoV-Brasil. Overall, 82.1% were female with a mean age of 49.7 (SD, 14.3) years; 22.7% of the patients were hospitalized, and 5.3% died because of COVID-19 (coronavirus disease 2019). Argentina and Brazil had both 4% of mortality and Mexico 9.4%. In the multivariable analysis, older age (≥60 years; odds ratio [OR], 7.4; 95% confidence interval [CI], 4.6-12.4), male sex (OR, 1.5; 95% CI, 1.1-2.1), living in Mexico (OR, 3.0; 95% CI, 2.0-4.4), comorbidity count (1 comorbidity: OR, 1.5; 95% CI, 1.0-2.1), diagnosis of connective tissue disease or vasculitis (OR, 1.8; 95% CI, 1.3-2.4), and other diseases (OR, 2.6; 95% CI, 1.6-4.1) compared with inflammatory joint disease, high disease activity (OR, 4.2; 95% CI, 2.5-7.0), and treatment with glucocorticoids (OR, 1.9; 95% CI, 1.4-2.5) or rituximab (OR, 4.2; 95% CI, 2.7-6.6) were associated with mortality. CONCLUSIONS: Mortality in patients with IMIDs was particularly high in Mexicans. Ethnic, environmental, societal factors, and different COVID-19 mitigation measures adopted have probably influenced these results.

The 2023 Orthopedic Research Society's international consensus meeting on musculoskeletal infection: Summary from the in vitro section.

Antimicrobial strategies for musculoskeletal infections are typically first developed with in vitro models. The In Vitro Section of the 2023 Orthopedic Research Society Musculoskeletal Infection international consensus meeting (ICM) probed our state of knowledge of in vitro systems with respect to bacteria and biofilm phenotype, standards, in vitro activity, and the ability to predict in vivo efficacy. A subset of ICM delegates performed systematic reviews on 15 questions and made recommendations and assessment of the level of evidence that were then voted on by 72 ICM delegates. Here, we report recommendations and rationale from the reviews and the results of the internet vote. Only two questions received a ≥90% consensus vote, emphasizing the disparate approaches and lack of established consensus for in vitro modeling and interpretation of results. Comments on knowledge gaps and the need for further research on these critical MSKI questions are included.

The 2023 Orthopaedic Research Society's International Consensus Meeting on musculoskeletal infection: Summary from the host immunity section.

Musculoskeletal infections (MSKI), which are a major problem in orthopedics, occur when the pathogen eludes or overwhelms the host immune system. While effective vaccines and immunotherapies to prevent and treat MSKI should be possible, fundamental knowledge gaps in our understanding of protective, nonprotective, and pathogenic host immunity are prohibitive. We also lack critical knowledge of how host immunity is affected by the microbiome, implants, prior infection, nutrition, antibiotics, and concomitant therapies, autoimmunity, and other comorbidities. To define our current knowledge of these critical topics, a Host Immunity Section of the 2023 Orthopaedic Research Society MSKI International Consensus Meeting (ICM) proposed 78 questions. Systematic reviews were performed on 15 of these questions, upon which recommendations with level of evidence were voted on by the 72 ICM delegates, and another 12 questions were voted on with a recommendation of "Unknown" without systematic reviews. Two questions were transferred to another ICM Section, and the other 45 were tabled for future consideration due to limitations of available human resources. Here we report the results of the voting with internet access to the questions, recommendations, and rationale from the systematic reviews. Eighteen questions received a consensus vote of ≥90%, while nine recommendations failed to achieve this threshold. Commentary on why consensus was not achieved on these questions and potential ways forward are provided to stimulate specific funding mechanisms and research on these critical MSKI host defense questions.

Empowerment-based nutrition interventions on blood pressure: a randomized comparative effectiveness trial.

Introduction: Empowerment lifestyle programs are needed to reduce the risk of hypertension. Our study compared the effectiveness of two empowerment-based approaches toward blood pressure (BP) reduction: salt reduction-specific program vs. healthy lifestyle general program. Methods: Three hundred and eleven adults (median age of 44 years, IQR 34-54 years) were randomly assigned to a salt reduction (n = 147) or a healthy lifestyle program (n = 164). The outcome measures were urinary sodium (Na+) and potassium (K+) excretion, systolic (SBP) and diastolic (DBP) blood pressure, weight, and waist circumference. Results: There were no significant differences in primary and secondary outcomes between the two program groups. When comparing each program to baseline, the program focused on salt reduction was effective in lowering BP following a 12-week intervention with a mean change of -2.5 mm Hg in SBP (95% CI, -4.1 to -0.8) and - 2.7 mm Hg in DBP (95% CI, -3.8 to -1.5) in the intention-to-treat (ITT) analysis. In the complete-case (CC) analysis, the mean change was -2.1 mm Hg in SBP (95% CI, -3.7 to -0.5) and - 2.3 mm Hg in DBP (95% CI, -3.4 to -1.1). This effect increases in subjects with high-normal BP or hypertension [SBP - 7.9 mm Hg (95% CI, -12.5 to -3.3); DBP - 7.3 mm Hg (95% CI, -10.2 to -4.4)]. The healthy lifestyle group also exhibited BP improvements after 12 weeks; however, the changes were less pronounced compared to the salt reduction group and were observed only for DBP [mean change of -1.5 mm Hg (95% CI, -2.6 to -0.4) in ITT analysis and - 1.4 mm Hg (95% CI, -2.4 to -0.3) in CC analysis, relative to baseline]. Overall, improvements in Na+/K+ ratio, weight, and Mediterranean diet adherence resulted in clinically significant SBP decreases. Importantly, BP reduction is attributed to improved dietary quality, rather than being solely linked to changes in the Na+/K+ ratio. Conclusion: Salt-focused programs are effective public health tools mainly in managing individuals at high risk of hypertension. Nevertheless, in general, empowerment-based approaches are important strategies for lowering BP, by promoting health literacy that culminates in adherence to the Mediterranean diet and weight reduction.

Therapeutic Liquid Eutectic Solvents in Lipid Nanoparticles as Drug Vehicles-A Proof of Concept.

Tuberculosis is an infectious disease caused by the bacterial complex Mycobacterium tuberculosis. Despite the decline in the incidence and mortality of this disease over the years, the emergence of new strains of tuberculosis resistant to existing tuberculostatic drugs is currently one of the largest public health problems. The engineering and development of new drugs is a complex process; therefore, the modification and enhancement of the drugs already marked is a better and faster solution. Ethambutol (ETB) is an antimycobacterial drug used to treat tuberculosis; however, it is highly hygroscopic and is sparingly soluble in water. Therapeutic Deep Eutectic Solvents (THEDESs) are known to improve drug solubility, permeability, and hygroscopicity, among others. In this study, three THEDESs of ETB were synthesized with sucralose, glucose and glycerol and then encapsulated in nanostructured lipid carriers to improve their stability. This work is a proof of concept on the possibility of encapsulating the THEDESs, and results show that the encapsulation of ETB is possible, yielding formulations with a loading capacity superior to 8.5% and able to incorporate THEDESs and not just ETB.

Portuguese Heart Failure Prevalence Observational Study (PORTHOS) rationale and design - A population-based study.

INTRODUCTION AND OBJECTIVES: Current epidemiological data on heart failure (HF) in Portugal derives from studies conducted two decades ago. The main aim of this study is to determine HF prevalence in the Portuguese population. Using current standards, this manuscript aims to describe the methodology and research protocol applied. METHODS: The Portuguese Heart Failure Prevalence Observational Study (PORTHOS) is a large, three-stage, population-based, nationwide, cross-sectional study. Community-dwelling citizens aged 50 years and older will be randomly selected via stratified multistage sampling. Eligible participants will be invited to attend a screening visit at a mobile clinic for HF symptom assessment, anthropomorphic assessment, N-terminal pro-B-type natriuretic peptide (NT-proBNP) testing, one-lead electrocardiogram (ECG) and a sociodemographic and health-related quality of life questionnaire (EQ-5D). All subjects with NT-proBNP ≥125 pg/mL or with a prior history of HF will undergo a diagnostic confirmatory assessment at the mobile clinic composed of a 12-lead ECG, comprehensive echocardiography, HF questionnaire (KCCQ) and blood sampling. To validate the screening procedure, a control group will undergo the same diagnostic assessment. Echocardiography results will be centrally validated, and HF diagnosis will be established according to the European Society of Cardiology HF guidelines. A random subsample of patients with an equivocal HF with preserved ejection fraction diagnosis based on the application of the Heart Failure Association preserved ejection fraction diagnostic algorithm will be invited to undergo an exercise echocardiography. CONCLUSIONS: Through the application of current standards, appropriate methodologies, and a strong research protocol, the PORTHOS study will determine the prevalence of HF in mainland Portugal and enable a comprehensive characterization of HF patients, leading to a better understanding of their clinical profile and health-related quality of life.

Changes in Microbiota Profile in the Proximal Remnant Intestine in Infants Undergoing Surgery Requiring Enterostomy.

Early-life gut dysbiosis has been associated with an increased risk of inflammatory, metabolic, and immune diseases later in life. Data on gut microbiota changes in infants undergoing intestinal surgery requiring enterostomy are scarce. This prospective cohort study examined the enterostomy effluent of 29 infants who underwent intestinal surgery due to congenital malformations of the gastrointestinal tract, necrotizing enterocolitis, or spontaneous intestinal perforation. Initial effluent samples were collected immediately after surgery and final effluent samples were collected three weeks later. Gut microbiota composition was analysed using real-time PCR and 16S rRNA gene sequencing. Three weeks after surgery, an increase in total bacteria number (+21%, p = 0.026), a decrease in Staphylococcus (-21%, p = 0.002) and Candida spp. (-16%, p = 0.045), and an increase in Lactobacillus (+3%, p = 0.045) and in less abundant genera belonging to the Enterobacteriales family were found. An increase in alpha diversity (Shannon's and Simpson's indexes) and significant alterations in beta diversity were observed. A correlation of necrotizing enterocolitis with higher Staphylococcus abundance and higher alpha diversity was also observed. H2-blockers and/or proton pump inhibitor therapy were positively correlated with a higher total bacteria number. In conclusion, these results suggest that positive changes occur in the gut microbiota profile of infants three weeks after intestinal surgery.

Delayed host mortality and immune response upon infection with P. aeruginosa persister cells.

Chronic infections are a heavy burden on healthcare systems worldwide. Persister cells are thought to be largely responsible for chronic infection due to their tolerance to antimicrobials and recalcitrance to innate immunity factors. Pseudomonas aeruginosa is a common and clinically relevant pathogen that contains stereotypical persister cells. Despite their importance in chronic infection, there have been limited efforts to study persister cell infections in vivo. Drosophila melanogaster has a well-described innate immune response similar to that of vertebrates and is a good candidate for the development of an in vivo model of infection for persister cells. Similar to what is observed in other bacterial strains, in this work we found that infection with P. aeruginosa persister cells resulted in a delayed mortality phenotype in Caenorhabditis elegans, Arabidopsis thaliana, and D. melanogaster compared to infection with regular cells. An in-depth characterization of infected D. melanogaster found that bacterial loads differed between persister and regular cells' infections during the early stages. Furthermore, hemocyte activation and antimicrobial peptide expression were delayed/reduced in persister infections over the same time course, indicating an initial suppression of, or inability to elicit, the fly immune response. Overall, our findings support the use of D. melanogaster as a model in which to study persister cells in vivo, where this bacterial subpopulation exhibits delayed virulence and an attenuated immune response.

Children with extended oligoarticular and polyarticular juvenile idiopathic arthritis have alterations in B and T follicular cell subsets in peripheral blood and a cytokine profile sustaining B cell activation.

OBJECTIVES: The main goal of this study was to characterise the frequency and phenotype of B, T follicular helper (Tfh) and T follicular regulatory (Tfr) cells in peripheral blood and the cytokine environment present in circulation in children with extended oligoarticular juvenile idiopathic arthritis (extended oligo JIA) and polyarticular JIA (poly JIA) when compared with healthy controls, children with persistent oligoarticular JIA (persistent oligo JIA) and adult JIA patients. METHODS: Blood samples were collected from 105 JIA patients (children and adults) and 50 age-matched healthy individuals. The frequency and phenotype of B, Tfh and Tfr cells were evaluated by flow cytometry. Serum levels of APRIL, BAFF, IL-1ß, IL-2, IL-4, IL-6, IL-10, IL-17A, IL-21, IL-22, IFN-γ, PD-1, PD-L1, sCD40L, CXCL13 and TNF were measured by multiplex bead-based immunoassay and/or ELISA in all groups included. RESULTS: The frequency of B, Tfh and Tfr cells was similar between JIA patients and controls. Children with extended oligo JIA and poly JIA, but not persistent oligo JIA, had significantly lower frequencies of plasmablasts, regulatory T cells and higher levels of Th17-like Tfh cells in circulation when compared with controls. Furthermore, APRIL, BAFF, IL-6 and IL-17A serum levels were significantly higher in paediatric extended oligo JIA and poly JIA patients when compared with controls. These immunological alterations were not found in adult JIA patients in comparison to controls. CONCLUSIONS: Our results suggest a potential role and/or activation profile of B and Th17-like Tfh cells in the pathogenesis of extended oligo JIA and poly JIA, but not persistent oligo JIA.

Effects of Physical Activity and Nutrition Education on the Gut Microbiota in Overweight and Obese Children.

Childhood obesity continues to represent a growing challenge, and it has been associated with gut microbiota dysbiosis. This study examines the gut microbiota composition in overweight and obese school children and assesses whether a 12-week multidisciplinary intervention can induce changes in the gut microbiota. The intervention, which combined recreational football and nutritional education, was implemented among 15 school children, aged 7-10 years, with a Body Mass Index ≥ 85th percentile. The children were assigned into two groups: Football Group (n = 9) and Nutrition and Football Group (n = 6). Faecal samples were collected at the beginning and end of the program and analysed by sequencing the 16S rRNA gene. Over the intervention, a significant decrease was found collectively for Bifidobacterium genera (p = 0.011) and for Roseburia genera in the Football Group (p = 0.021). The relative abundance of Roseburia (p = 0.002) and Roseburia faecis (p = 0.009) was negatively correlated with moderate to vigorous physical activity (MVPA), while Prevotella copri was positively correlated with MVPA (p = 0.010) and with the daily intake of protein (p = 0.008). Our findings suggest that a multidisciplinary intervention was capable of inducing limited but significant positive changes in the gut microbiota composition in overweight and obese school children.

Subversion of the Complement System by Pseudomonas aeruginosa.

Pseudomonas aeruginosa is an opportunistic pathogen heavily implicated in chronic diseases. Immunocompromised patients that become infected with P. aeruginosa usually are afflicted with a lifelong chronic infection, leading to worsened patient outcomes. The complement system is an integral piece of the first line of defense against invading microorganisms. Gram-negative bacteria are thought to be generally susceptible to attack from complement; however, P. aeruginosa can be an exception, with certain strains being serum resistant. Various molecular mechanisms have been described that confer P. aeruginosa unique resistance to numerous aspects of the complement response. In this review, we summarize the current published literature regarding the interactions of P. aeruginosa and complement, as well as the mechanisms used by P. aeruginosa to exploit various complement deficiencies and the strategies used to disrupt or hijack normal complement activities.

Effect of sphingosine and inoculum concentrations on Staphylococcus aureus and Staphylococcus epidermidis biofilms.

Atopic dermatitis (AD) is a chronic inflammatory skin disease where patients are more susceptible to infection and inflammation. The most salient symptoms of atopic dermatitis (AD) are skin dysbiosis and ceramide deficiency. Here, the effect of AD conditions on S. aureus resilience was investigated. S. aureus and S. epidermidis biofilms were co-inoculated at healthy and AD bacterial ratios and exposed to various sphingosine dosing regimens. In both healthy (S. epidermidis dominant) and AD (S. aureus dominant) conditions the viability of the non-dominant bacterial species was affected. Quorum sensing (QS)-impaired S. aureus was overall more susceptible to sphingosine. Despite the general resilience of QS-intact S. aureus against sphingosine, modulation of S. epidermidis (healthy ratio) and sphingosine (healthy Sph) led to a lack of recovery from its initial killing. Overall, it was found that when in biofilms, S. epidermidis increases S. aureus resilience to sphingosine, possibly enhancing the pathogen's recalcitrance in AD skin.

An In Vitro Small Intestine Model Incorporating a Food Matrix and Bacterial Mock Community for Intestinal Function Testing.

Consumed food travels through the gastrointestinal tract to reach the small intestine, where it interacts with the microbiota, forming a complex relationship with the dietary components. Here we present a complex in vitro cell culture model of the small intestine that includes human cells, digestion, a simulated meal, and a microbiota represented by a bacterial community consisting of E. coli, L. rhamnosus, S. salivarius, B. bifidum, and E. faecalis. This model was used to determine the effects of food-grade titanium dioxide nanoparticles (TiO2 NPs), a common food additive, on epithelial permeability, intestinal alkaline phosphatase activity, and nutrient transport across the epithelium. Physiologically relevant concentrations of TiO2 had no effect on intestinal permeability but caused an increase in triglyceride transport as part of the food model, which was reversed in the presence of bacteria. Individual bacterial species had no effect on glucose transport, but the bacterial community increased glucose transport, suggesting a change in bacterial behavior when in a community. Bacterial entrapment within the mucus layer was reduced with TiO2 exposure, which may be due to decreased mucus layer thickness. The combination of human cells, a synthetic meal, and a bacterial mock community provides an opportunity to understand the implications of nutritional changes on small intestinal function, including the microbiota.

Neurodifferentiation and Neuroprotection Potential of Mesenchymal Stromal Cell-Derived Secretome Produced in Different Dynamic Systems.

Parkinson's disease (PD) is the second most common neurodegenerative disorder and is characterized by the degeneration of the dopamine (DA) neurons in the substantia nigra pars compacta, leading to a loss of DA in the basal ganglia. The presence of aggregates of alpha-synuclein (α-synuclein) is seen as the main contributor to the pathogenesis and progression of PD. Evidence suggests that the secretome of mesenchymal stromal cells (MSC) could be a potential cell-free therapy for PD. However, to accelerate the integration of this therapy in the clinical setting, there is still the need to develop a protocol for the large-scale production of secretome under good manufacturing practices (GMP) guidelines. Bioreactors have the capacity to produce large quantities of secretomes in a scalable manner, surpassing the limitations of planar static culture systems. However, few studies focused on the influence of the culture system used to expand MSC, on the secretome composition. In this work, we studied the capacity of the secretome produced by bone marrow-derived mesenchymal stromal cells (BMSC) expanded in a spinner flask (SP) and in a Vertical-Wheel™ bioreactor (VWBR) system, to induce neurodifferentiation of human neural progenitor cells (hNPCs) and to prevent dopaminergic neuron degeneration caused by the overexpression of α-synuclein in one Caenorhabditis elegans model of PD. Results showed that secretomes from both systems were able to induce neurodifferentiation, though the secretome produced in the SP system had a greater effect. Additionally, in the conditions of our study, only the secretome produced in SP had a neuroprotective potential. Lastly, the secretomes had different profiles regarding the presence and/or specific intensity of different molecules, namely, interleukin (IL)-6, IL-4, matrix metalloproteinase-2 (MMP2), and 3 (MMP3), tumor necrosis factor-beta (TNF-ß), osteopontin, nerve growth factor beta (NGFß), granulocyte colony-stimulating factor (GCSF), heparin-binding (HB) epithelial growth factor (EGF)-like growth factor (HB-EGF), and IL-13. Overall, our results suggest that the culture conditions might have influenced the secretory profiles of cultured cells and, consequently, the observed effects. Additional studies should further explore the effects that different culture systems have on the secretome potential of PD.

The impact of Hafnia alvei HA4597™ on weight loss and glycaemic control after bariatric surgery - study protocol for a triple-blinded, blocked randomized, 12-month, parallel-group, placebo-controlled clinical trial.

BACKGROUND: Subjects with obesity exhibit changes in gut microbiota composition and function (i.e. dysbiosis) that contribute to metabolic dysfunction, including appetite impairment. Although bariatric surgery is an effective treatment for obesity with a great impact on weight loss, some subjects show weight regain due to increased energy intake after the surgery. This surgery involves gut microbiota changes that promote appetite control, but it seems insufficient to completely restore the obesity-associated dysbiosis - a possible contributor for weight regain. Thus, modulating gut microbiota with probiotics that could improve appetite regulation as a complementary approach to post-operative diet (i.e. Hafnia alvei HA4597™), may accentuate post-surgery weight loss and insulin sensitivity. METHODS: This is a protocol of a triple-blinded, blocked-randomized, parallel-group, placebo-controlled clinical trial designed to determine the effect of Hafnia alvei HA4597™ supplementation on weight loss and glycaemic control 1 year after bariatric surgery. Patients of Hospital CUF Tejo, Lisbon, that undergo Roux-en-Y gastric bypass are invited to participate in this study. Men and women between 18 and 65 years old, with a BMI ≥ 35 kg/m2 and at least one severe obesity-related comorbidity, or with a BMI ≥ 40 kg/m2, and who are willing to take 2 capsules of Hafnia alvei HA4597™ probiotic supplements (equivalent to 5 × 107 CFU) vs. placebo per day for 90 days are included in this study. Assessments are carried out at baseline, 3, 6, 9, and 12 months after the surgery. Loss of weight in excess and glycated haemoglobin are considered primary outcomes. In addition, changes in other metabolic and inflammatory outcomes, gut microbiota composition and metabolites, as well as gastrointestinal quality of life are also being assessed during the trial. DISCUSSION: The evidence obtained in this study will provide relevant information regarding the profile of the intestinal microbiota of individuals with severe obesity and the identification of the risk/benefit ratio of the use of Hafnia alvei HA4597™ as an adjunctive treatment in the maintenance of metabolic and weight control one year after the surgical intervention. TRIAL REGISTRATION: ClinicalTrials.gov NCT05170867. Registered on 28 December 2021.

Synergism between chikungunya virus infection and rheumatoid arthritis on cytokine levels: Clinical implications?

Post-chikungunya virus (CHIKV) chronic arthritis shares several immunopathogenic mechanisms with rheumatoid arthritis (RA), which has led to discussions about the probable relationship between the two diseases. Indeed, some studies have suggested a role for CHIKV infection in RA development. However, to the best of our knowledge, the influence of CHIKV on previous RA has not yet been demonstrated. Herein, we analyzed the potential synergism between CHIKV infection and RA on cytokine and chemokine levels. For this, we compared the IL-1ß, IL-6, IL-10, IL-17A, CCL2, CXCL8, CXCL9 and CXCL10 levels, in addition to rheumatoid factor (RF) and C-reactive protein (CRP), in patients with post-CHIKV chronic arthritis (named CHIKV group), patients with RA (RA group), and patients with previous RA who were later infected by CHIKV (RA-CHIKV). History of CHIKV infection was confirmed by serology (IgG, ELISA). Cytokines/chemokines were quantified by flow cytometry. RF, CRP, age and sex data were obtained from medical records. IL-1ß, IL-6, IL-10 and IL-17A levels were significantly higher in RA-CHIKV compared to the other groups. CXCL8 levels were higher in the CHIKV group than in RA. CXCL9 was higher in CHIKV than in the RA-CHIKV group. CXCL10 was higher in CHIKV than in the other groups. FR levels were higher in RA than in the CHIKV group, and in RA-CHIKV than in CHIKV. No significant difference was observed in CCL2 and CRP, as well as in age and sex. Finally, our findings suggest an interplay between CHIKV infection and RA, which must be analyzed for its possible clinical impact.

Immune Response Modulation by Pseudomonas aeruginosa Persister Cells.

Bacterial persister cells-a metabolically dormant subpopulation tolerant to antimicrobials-contribute to chronic infections and are thought to evade host immunity. In this work, we studied the ability of Pseudomonas aeruginosa persister cells to withstand host innate immunity. We found that persister cells resist MAC-mediated killing by the complement system despite being bound by complement protein C3b at levels similar to regular vegetative cells, in part due to reduced bound C5b, and are engulfed at a lower rate (10- to 100-fold), even following opsonization. Once engulfed, persister cells resist killing and, contrary to regular vegetative cells which induce a M1 favored (CD80+/CD86+/CD206-, high levels of CXCL-8, IL-6, and TNF-α) macrophage polarization, they initially induce a M2 favored macrophage polarization (CD80+/CD86+/CD206+, high levels of IL-10, and intermediate levels of CXCL-8, IL-6, and TNF-α), which is skewed toward M1 favored polarization (high levels of CXCL-8 and IL-6, lower levels of IL-10) by 24 h of infection, once persister cells awaken. Overall, our findings further establish the ability of persister cells to evade the innate host response and to contribute chronic infections. IMPORTANCE Bacterial cells have a subpopulation-persister cells-that have a low metabolism. Persister cells survive antimicrobial treatment and can regrow to cause chronic and recurrent infections. Currently little is known as to whether the human immune system recognizes and responds to the presence of persister cells. In this work, we studied the ability of persister cells from Pseudomonas aeruginosa to resist the host defense system (innate immunity). We found that this subpopulation is recognized by the defense system, but it is not killed. The lack of killing likely stems from hindering the immune response regulation, resulting in a failure to distinguish whether a pathogen is present. Findings from this work increase the overall knowledge as to how chronic infections are resilient.

Sustained Release of Human Adipose Tissue Stem Cell Secretome from Star-Shaped Poly(ethylene glycol) Glycosaminoglycan Hydrogels Promotes Motor Improvements after Complete Transection in Spinal Cord Injury Rat Model.

Adipose tissue-derived stem cells (ASCs) have been shown to assist regenerative processes after spinal cord injury (SCI) through their secretome, which promotes several regenerative mechanisms, such as inducing axonal growth, reducing inflammation, promoting cell survival, and vascular remodeling, thus ultimately leading to functional recovery. However, while systemic delivery (e.g., i.v. [intravenous]) may cause off-target effects in different organs, the local administration has low efficiency due to fast clearance by body fluids. Herein, a delivery system for human ASCs secretome based on a hydrogel formed of star-shaped poly(ethylene glycol) (starPEG) and the glycosaminoglycan heparin (Hep) that is suitable to continuously release pro-regenerative signaling mediators such as interleukin (IL)-4, IL-6, brain-derived neurotrophic factor, glial-cell neurotrophic factor, and beta-nerve growth factor over 10 days, is reported. The released secretome is shown to induce differentiation of human neural progenitor cells and neurite outgrowth in organotypic spinal cord slices. In a complete transection SCI rat model, the secretome-loaded hydrogel significantly improves motor function by reducing the percentage of ameboid microglia and systemically elevates levels of anti-inflammatory cytokines. Delivery of ASC-derived secretome from starPEG-Hep hydrogels may therefore offer unprecedented options for regenerative therapy of SCI.