Macrophages, IL-10, and nitric oxide increase, induced by hyperglycemic conditions, impact the development of murine melanoma B16F10-Nex2.

Epidemiological studies show a strong correlation between diabetes and the increased risk of developing different cancers, including melanoma. In the present study, we investigated the impact of a streptozotocin (STZ)-induced hyperglycemic environment on B16F10-Nex2 murine melanoma development. Hyperglycemic male C57Bl/6 mice showed increased subcutaneous tumor development, partially inhibited by metformin. Tumors showed increased infiltrating macrophages, and augmented IL-10 and nitric oxide (NO) concentrations. In vivo neutralization of IL-10, NO synthase inhibition, and depletion of macrophages reduced tumor development. STZ-treated TLR4 KO animals showed delayed tumor development; the transfer of hyperglycemic C57Bl/6 macrophages to TLR4 KO reversed this effect. Increased concentrations of IL-10 present in tumor homogenates of hyperglycemic mice induced a higher number of pre-angiogenic structures in vitro, and B16F10-Nex2 cells incubated with different glucose concentrations in vitro produced increased levels of IL-10. In summary, our findings show that a hyperglycemic environment stimulates murine melanoma B16F10-Nex2 primary tumor growth, and this effect is dependent on tumor cell stimulation, increased numbers of macrophages, and augmented IL-10 and NO concentrations. These findings show the involvement of tumor cells and other components of the tumor microenvironment in the development of subcutaneous melanoma under hyperglycemic conditions, defining novel targets for melanoma control in diabetic patients.

The effect of antimalarials on the safety and persistence of treatment with biologic agents or Janus kinase inhibitors in rheumatoid arthritis.

OBJECTIVES: To test the association of use of antimalarials with the overall safety of treatment in RA patients receiving one or multiple courses of biologic (b)DMARDs or a Janus kinase inhibitor (JAKi). METHODS: BiobadaBrasil is a multicentric registry-based cohort study of Brazilian patients with rheumatic diseases starting their first bDMARD or JAKi. The present analysis includes RA patients recruited from January 2009 to October 2019, followed up over one or multiple (up to six) courses of treatment (latest date, 19 November 2019). The primary outcome was the incidence of serious adverse events (SAEs). Total and system-specific adverse events (AEs) and treatment interruption served as secondary outcomes. Negative binomial regression with generalized estimating equations (to estimate multivariate incidence rate ratios, mIRR) and frailty Cox proportional hazards models were used for statistical analyses. RESULTS: The number of patients enrolled was 1316 (2335 treatment courses, 6711 patient-years [PY]; 1254.5 PY on antimalarials). The overall incidence of SAEs was 9.2/100 PY. Antimalarials were associated with reduced risk of SAEs (mIRR: 0.49; 95% CI: 0.36, 0.68; P < 0.001), total AEs (0.68; 95% CI: 0.56, 0.81; P < 0.001), serious infections (0.53; 95% CI: 0.34, 0.84; P = 0.007) and total hepatic AEs (0.21; 95% CI: 0.05, 0.85; P = 0.028). Antimalarials were also related to better survival of treatment course (P = 0.003). There was no significant increase in the risk of cardiovascular AEs. CONCLUSION: Among RA patients on treatment with bDMARDs or JAKi, concomitant use of antimalarials was associated with reduced the incidence of serious and total AEs and with longer treatment course survival.

University indigenous students' perspectives on climate change and survival of indigenous peoples in Brazil: a concept mapping study.

Introduction: This study aimed to identify what indigenous university students in Brazil perceived to be important and feasible actions to protect the survival of indigenous peoples from climate change-related impacts. Methods: Concept mapping, which is a participatory mixed methodology, was conducted virtually with 20 indigenous students at two universities in Brazil. A focus prompt was developed from consultations with indigenous stakeholders and read "To protect the survival of the Indigenous Peoples from climate change, it is necessary to…". Students brainstormed 46 statements, which they then sorted into clusters based on conceptual similarity. They rated each statement for importance and feasibility. Quantitative multivariate analyses of clusters and ratings were conducted to produce multiple visual maps of perceived actionable priorities. These analyses used the Group Wisdom TM software. Results: Students agreed on 8 clusters that reflect the factors that influence the survival of indigenous peoples-preservation of lands 0.16 (SD 0.13), protection of demarcated lands 0.31 (SD 0.10), indigenous health and wellbeing 0.35 (SD 0.14), ancestral customs 0.46 (SD 0.04), global and national actions 0.61 (SD 0.13), indigenous rights 0.64 (SD 0.23), collective living 0.71 (SD 0.21), and respect 0.75 (SD 0.14). Discussion: The most actionable priorities are related to the respect for their lands and customs, educational initiatives in schools about the importance of indigenous peoples to society, guarantees for basic health rights, and culturally appropriate provision of care, with specific mention of mental healthcare. The findings aligned closely with the concept of indigenous self-determination, which is rooted in autonomy and respect for cultural diversity, and the right to make decisions that impact their lives, land, and resources.

Climate change and mental health of Indigenous peoples living in their territory: a concept mapping study.

Background: The alarming increase in annual deforestation rates has had devastating consequences in climate change, and it is affecting Indigenous people, who depend entirely on the land for survival and has also weakened the rainforest's crucial role in stabilizing the global climate. Recognizing and respecting Indigenous people's needs and social, economic, and historical conditions influence health and healthcare. This study aimed to conduct online concept mapping workshops with university students to identify perceived important and feasible actions for improving the mental health of Indigenous people living in their territory in association with climate change. Methods: Concept mapping, a participatory mixed methodology, was conducted virtually with 20 Indigenous students at two universities in Brazil. A focus prompt was developed from consultations with Indigenous stakeholders and read-"To improve the mental health of Indigenous peoples in their territory during climate change crises, it is necessary to…." Results: University students organized 42 unique statements in 6 clusters that cover a wide range of topics: family support, 0.68 (SD 0.19); respect and understanding, 0.37 (SD 0.08); improvement actions, 0.52 (SD 0.07); public policies in favor of Indigenous people's mental health, 0.24 (0.09); health actions, 0.15 (SD 0.08); Indigenous training in health and its importance in improving mental health 0.32 (SD 0.07). Conclusion: These clusters range from community initiatives, public policies, health actions, and strengthening professional services in Indigenous communities. These all provide numerous concrete ideas for developing interventions designed to address mental health challenges associated with climate change.

Co-developing a health promotion programme for indigenous youths in Brazil: A concept mapping report.

BACKGROUND: Latin America and the Caribbean Region are home to about 42 million Indigenous people, with about 900,000 living in Brazil. The little routinely collected population-level data from Indigenous communities in the region available shows stark inequities in health and well-being. There are 305 Indigenous ethnic groups, speaking 274 languages, spread across the remote national territory, who have endured long-lasting inequities related to poverty, poor health, and limited access to health care. Malnutrition and mental health are key concerns for young people. Building on our Indigenous communities-academic partnerships over the last two decades, we collaborated with young people from the Terena Indigenous ethnic group, village leaders, teachers, parents, and local health practitioners from the Polo Base (community health centres) to obtain their perspectives on important and feasible actions for a youth health promotion programme. METHODS: The report was conducted in the Tereré Village in Mato Grosso do Sul. Concept mapping, a participatory mixed method approach, was conducted in 7 workshops, 15 adults and 40 youths aged 9-17 years. Art-based concept mapping was used with 9 to 11 years old children (N = 20). Concept systems software was used to create concept maps, which were finalised during the workshops. Focused prompts related to factors that may influence the health and happiness of youths. The participatory method gave Terena youths a significant voice in shaping an agenda that can improve their health. RESULTS: Terena youths identified priority actions that clustered under 'Family', 'School', 'Education', 'Socio-economic circumstances', 'Respect' and 'Sport' in response to protecting happiness; and 'Nutrition pattern', 'Physical activity', 'Local environment', and 'Well-being' in response to having a healthy body. Through the participatory lens of concept mapping, youths articulated the interconnectedness of priority actions across these clusters such that behaviours (e.g. Nutrition pattern, drinking water, physical activity) and aspirations (being able to read, to have a good job) were recognised to be dependent on a wider ecology of factors (e.g. loss of eco-systems, parent-child relationships, student- teacher relationships, parental unemployment). In response to developing youth health, Terena adults suggested priority actions that clustered under 'Relationships', 'Health issues', 'Prevention at Polo Base', 'Access to health care', 'Communication with young people', 'Community life', 'Raising awareness' and 'School support'. Their priorities reflected the need for structural transformative actions (e.g. Polo Base and school staff working together) and for embedding actions to protect Indigenous culture (e.g. integrating their cultural knowledge into training programmes). CONCLUSIONS: Concept maps of Indigenous youths emphasised the need for a health promotion programme that engages with the structural and social determinants of health to protect their happiness and health, whilst those of adults emphasised the need to address specific health issues through preventative care via a school-Polo Base collaboration. Investment in a co-developed school-Polo-Base health promotion programme, with intersectoral engagement, has potential for making Indigenous health systems responsive to the inequalities of youth health, to yield dividends for healthy ageing trajectories as well as for the health of the next generation.

Mothers of children with Down syndrome: a clinical and epidemiological study.

Down syndrome is the main genetic cause of intellectual disability. Many studies describe the clinical characteristics of DS patients; however, few have investigated the clinical profile of mothers who have children with DS. Advanced maternal age (≥ 35 years old) is a risk factor for DS. Although there is an overall increase in pregnancies among women with advanced maternal age, there is still a lack of awareness of the increased risk of aneuploidy. Here, we reported the clinical and epidemiological profile of DS children and their mothers in a public reference hospital in the State of Rio de Janeiro, Brazil. For data collection, we performed a face-to-face interview guided by a structured questionnaire with closed-ended questions. A total of 344 individuals, 172 mothers and their DS children, were included in this study. Our results show that 56% of the mothers sampled were ≥ 35 years of age at childbirth. Although 98% of them received prenatal care, only 4% obtained a prenatal diagnosis of DS. Most mothers reported not drinking alcohol or smoking cigarettes during pregnancy. Furthermore, 91% of women took prenatal vitamins and supplements; however, 47% were not aware of their benefits for a healthy pregnancy. Given the strict correlation between advanced maternal age and DS, prenatal care should include genetic counseling for women over 35 years of age. This study highlights the importance of prenatal care and the urgent need for better DS screening allowing for immediate postnatal care, positively impacting the life expectancy of these patients.

Dental anomaly detection using intraoral photos via deep learning.

Children with orofacial clefting (OFC) present with a wide range of dental anomalies. Identifying these anomalies is vital to understand their etiology and to discern the complex phenotypic spectrum of OFC. Such anomalies are currently identified using intra-oral exams by dentists, a costly and time-consuming process. We claim that automating the process of anomaly detection using deep neural networks (DNNs) could increase efficiency and provide reliable anomaly detection while potentially increasing the speed of research discovery. This study characterizes the use of` DNNs to identify dental anomalies by training a DNN model using intraoral photographs from the largest international cohort to date of children with nonsyndromic OFC and controls (OFC1). In this project, the intraoral images were submitted to a Convolutional Neural Network model to perform multi-label multi-class classification of 10 dental anomalies. The network predicts whether an individual exhibits any of the 10 anomalies and can do so significantly faster than a human rater can. For all but three anomalies, F1 scores suggest that our model performs competitively at anomaly detection when compared to a dentist with 8 years of clinical experience. In addition, we use saliency maps to provide a post-hoc interpretation for our model's predictions. This enables dentists to examine and verify our model's predictions.

Tooth Agenesis Patterns in Orofacial Clefting Using Tooth Agenesis Code: A Meta-Analysis.

Individuals with orofacial clefting (OFC) have a higher prevalence of tooth agenesis (TA) overall. Neither the precise etiology of TA, nor whether TA occurs in patterns that differ by gender or cleft type is yet known. This meta-analysis aims to identify the spectrum of tooth agenesis patterns in subjects with non-syndromic OFC and controls using the Tooth Agenesis Code (TAC) program. An indexed search of databases (PubMed, EMBASE, and CINAHL) along with cross-referencing and hand searches were completed from May to June 2019 and re-run in February 2022. Additionally, unpublished TAC data from 914 individuals with OFC and 932 controls were included. TAC pattern frequencies per study were analyzed using a random effects meta-analysis model. A thorough review of 45 records retrieved resulted in 4 articles meeting eligibility criteria, comprising 2182 subjects with OFC and 3171 controls. No TA (0.0.0.0) was seen in 51% of OFC cases and 97% of controls. TAC patterns 0.2.0.0, 2.0.0.0, and 2.2.0.0 indicating uni- or bi-lateral missing upper laterals, and 16.0.0.0 indicating missing upper right second premolar, were more common in subjects with OFC. Subjects with OFC have unique TA patterns and defining these patterns will help increase our understanding of the complex etiology underlying TA.

Genetic Analyses of Enamel Hypoplasia in Multiethnic Cohorts.

Enamel hypoplasia causes reduction in the thickness of affected enamel and is one of the most common dental anomalies. This defect is caused by environmental and/or genetic factors that interfere with tooth formation, emphasizing the importance of investigating enamel hypoplasia on an epidemiological and genetic level. A genome-wide association of enamel hypoplasia was performed in multiple cohorts, overall comprising 7,159 individuals ranging in age from 7-82 years. Mixed-models were used to test for genetic association while simultaneously accounting for relatedness and genetic population structure. Meta-analysis was then performed. More than 5 million single-nucleotide polymorphisms were tested in individual cohorts. Analyses of the individual cohorts and meta-analysis identified association signals close to genome-wide significance (P < 510-8), and many suggestive association signals (510-8 < P < 510-6) near genes with plausible roles in tooth/enamel development. The strongest association signal (P = 1.5710-9) was observed near BMP2K in one of the individual cohorts. Additional suggestive signals were observed near genes with plausible roles in tooth development in the meta-analysis, such as SLC4A4 which can influence enamel hypoplasia. Additional human genetic studies are needed to replicate these results and functional studies in model systems are needed to validate our findings.

Genome-wide association study of multiethnic nonsyndromic orofacial cleft families identifies novel loci specific to family and phenotypic subtypes.

Nonsyndromic orofacial clefts (OFCs) are among the most common craniofacial birth defects worldwide, and known to exhibit phenotypic and genetic heterogeneity. Cleft lip plus cleft palate (CLP) and cleft lip only (CL) are commonly combined together as one phenotype (CL/P), separately from cleft palate alone. In comparison, our study analyzes CL and CLP separately. A sample of 2218 CL and CLP cases, 4537 unaffected relatives of cases, and 2673 pure controls with no family history of OFC were selected from the Pittsburgh Orofacial Cleft (Pitt-OFC) multiethnic study.genome-wide association studies were run for seven specific phenotypes created based on the cleft type(s) observed within these families, as well as the combined CL/P phenotype. Five novel genome-wide significant associations, 3q29 (rs62284390), 5p13.2 (rs609659), 7q22.1 (rs6465810), 19p13.3 (rs628271), and 20q13.33 (rs2427238), and nine associations (p ≤ 1.0E-05) within previously confirmed OFC loci-PAX7, IRF6, FAM49A, DCAF4L2, 8q24.21, ARID3B, NTN1, TANC2 and the WNT9B:WNT3 gene cluster-were observed. We also found that single nucleotide polymorphisms within a subset of the associated loci, both previously known and novel, differ substantially in terms of their effects across cleft- or family-specific phenotypes, indicating not only etiologic differences between CL and CLP, but also genetic heterogeneity within each of the two OFC subtypes.

Prevalence of microcephaly: the Latin American Network of Congenital Malformations 2010-2017.

Objective: The Latin American Network of Congenital Malformations: ReLAMC was established in 2017 to provide accurate congenital anomaly surveillance. This study used data from ReLAMC registries to quantify the prevalence of microcephaly from 2010 to 2017 (before, during and after the Zika virus epidemic). Design: Nine ReLAMC congenital anomaly registries provided case-level data or aggregate data for any live births, still births or terminations of pregnancy with microcephaly. Births to pregnant women infected with Zika virus first occurred in Brazil in 2015, and in the remaining registry areas in 2016 with the exception of Chile that did not experience Zika virus. Therefore the prevalence of microcephaly for 2010-2014 and individual years 2015, 2016 and 2017 was estimated using multilevel random effect Poisson models. Clinical classification and characteristics of the cases were compared pre and post Zika for all centres providing individual case-level data. Results: The prevalence of microcephaly for all registries excluding Brazil was 2.3 per 10 000 (95% CI 2.0 to 2.6) for 2010-2014 rising to 5.4 (95% CI 4.8 to 6.0) in 2016 and 5.9 (95% CI 5.3 to 6.6) in 2017. Brazil had a prevalence of 0.6 per 10 000 (95% CI 0.5 to 0.6) in 2010-2014, rising to 5.8 (95% CI 5.6 to 6.1) in 2015, 8.0 (95% CI 7.6 to 8.3) in 2016 and then falling in 2017. Only 29 out of 687 cases of microcephaly were reported as congenital Zika syndrome in countries excluding Brazil. Conclusions: The prevalence of microcephaly was influenced both by Zika causing congenital Zika syndrome and by increased reporting awareness.

Enhancement of Antibiotic Activity by 1,8-Naphthyridine Derivatives against Multi-Resistant Bacterial Strains.

The search for new antibacterial agents has become urgent due to the exponential growth of bacterial resistance to antibiotics. Nitrogen-containing heterocycles such as 1,8-naphthyridine derivatives have been shown to have excellent antimicrobial properties. Therefore, the purpose of this study was to evaluate the antibacterial and antibiotic-modulating activities of 1,8-naphthyridine derivatives against multi-resistant bacterial strains. The broth microdilution method was used to determine the minimum inhibitory concentration (MIC) of the following compounds: 7-acetamido-1,8-naphthyridin-4(1H)-one and 3-trifluoromethyl-N-(5-chloro-1,8-naphthyridin-2-yl)-benzenesulfonamide. The antibiotic-modulating activity was analyzed using subinhibitory concentrations (MIC/8) of these compounds in combination with norfloxacin, ofloxacin, and lomefloxacin. Multi-resistant strains of Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus were used in both tests. Although the compounds had no direct antibacterial activity (MIC ≥ 1.024 µg/mL), they could decrease the MIC of these fluoroquinolones, indicating synergism was obtained from the association of the compounds. These results suggest the existence of a structure-activity relationship in this group of compounds with regard to the modulation of antibiotic activity. Therefore, we conclude that 1,8-naphthyridine derivatives potentiate the activity of fluoroquinolone antibiotics against multi-resistant bacterial strains, and thereby interesting candidates for the development of drugs against bacterial infections caused by multidrug resistant strains.

Genome-Wide Association Study (GWAS) of dental caries in diverse populations.

BACKGROUND: Dental caries is one of the most common chronic diseases and is influenced by a complex interplay of genetic and environmental factors. Most previous genetic studies of caries have focused on identifying genes that contribute to dental caries in specific ethnic groups, usually of European descent. METHODS: The aim of this study is to conduct a genome-wide association study (GWAS) to identify associations affecting susceptibility to caries in a large multiethnic population from Argentina, the Philippines, Guatemala, Hungary, and the USA, originally recruited for studies of orofacial clefts (POFC, N = 3686). Ages of the participants ranged from 2 to 12 years for analysis of the primary dentition, and 18-60 years for analysis of the permanent dentition. For each participant, dental caries was assessed by counts of decayed and filled teeth (dft/DFT) and genetic variants (single nucleotide polymorphisms, SNPs) were genotyped or imputed across the entire genome. Caries was analyzed separately for the primary and permanent dentitions, with age, gender, and presence/absence of any type of OFC treated as covariates. Efficient Mixed-Model Association eXpedited (EMMAX) was used to test genetic association, while simultaneously accounting for relatedness and stratification. RESULTS: We identified several suggestive loci (5 × 10-8 < P < 5 × 10-6) within or near genes with plausible biological roles for dental caries, including a cluster of taste receptor genes (TAS2R38, TAS2R3, TAS2R4, TASR25) on chromosome 7 for the permanent dentition analysis, and DLX3 and DLX4 on chromosome 17 for the primary dentition analysis. Genome-wide significant results were seen with SNPs in the primary dentition only; however, none of the identified genes near these variants have known roles in cariogenesis. CONCLUSION: The results of this study warrant further investigation and may lead to a better understanding of cariogenesis in diverse populations, and help to improve dental caries prediction, prevention, and/or treatment in future.

Safety of the Methotrexate-leflunomide Combination in Rheumatoid Arthritis: Results of a Multicentric, Registry-based, Cohort Study (BiobadaBrasil).

OBJECTIVE: To evaluate the safety of the methotrexate (MTX)-leflunomide (LEF) combination in rheumatoid arthritis (RA), comparing it with other therapeutic schemes involving conventional synthetic (cs-) and biologic (b-) disease-modifying antirheumatic drugs (DMARDs) or Janus kinase inhibitors (JAKi). METHODS: Patients with RA starting a treatment course with a csDMARD (without previous use of bDMARD or JAKi) or their first bDMARD/JAKi were followed up in a registry-based, multicentric cohort study in Brazil (BiobadaBrasil). The primary outcome was the incidence of serious adverse events (SAEs); secondary outcomes included serious infections. Multivariate Cox proportional hazards models and propensity score matching analysis (PSMA) were used for statistical comparisons. RESULTS: In total, 1671 patients (5349 patient-years [PY]) were enrolled; 452 patients (1537 PY) received MTX + LEF. The overall incidence of SAEs was 5.6 per 100 PY. The hazard of SAEs for MTX + LEF was not higher than for MTX or LEF (adjusted HR [aHR] 1.00, 95% CI 0.76-1.31, P = 0.98). MTX + LEF presented a lower hazard of SAEs (aHR 0.56, 95% CI 0.36-0.88, P = 0.01) and infectious SAEs (aHR 0.48, 95% CI 0.25-0.94, P = 0.03) than bDMARDs/JAKi with MTX or LEF. MTX + LEF presented lower hazard of SAEs than MTX + sulfasalazine (SSZ; aHR 0.33, 95% CI 0.16-0.65, P = 0.002). Analysis using PSMA confirmed the results obtained with traditional multivariate Cox analysis. CONCLUSION: In our study, MTX + LEF presented a relatively good overall safety profile in comparison to MTX + SSZ and schemes involving advanced therapies in RA.

Genome-Wide Association Study of Non-syndromic Orofacial Clefts in a Multiethnic Sample of Families and Controls Identifies Novel Regions.

Orofacial clefts (OFCs) are among the most prevalent craniofacial birth defects worldwide and create a significant public health burden. The majority of OFCs are non-syndromic and vary in prevalence by ethnicity. Africans have the lowest prevalence of OFCs (~ 1/2,500), Asians have the highest prevalence (~1/500), Europeans and Latin Americans lie somewhere in the middle (~1/800 and 1/900, respectively). Thus, ethnicity appears to be a major determinant of the risk of developing OFC. The Pittsburgh Orofacial Clefts Multiethnic study was designed to explore this ethnic variance, comprising a large number of families and individuals (~12,000 individuals) from multiple populations worldwide: US and Europe, Asians, mixed Native American/Caucasians, and Africans. In this current study, we analyzed 2,915 OFC cases, 6,044 unaffected individuals related to the OFC cases, and 2,685 controls with no personal or family history of OFC. Participants were grouped by their ancestry into African, Asian, European, and Central and South American subsets, and genome-wide association run on the combined sample as well as the four ancestry-based groups. We observed 22 associations to cleft lip with or without cleft palate at 18 distinct loci with p-values < 1e-06, including 10 with genome-wide significance (<5e-08), in the combined sample and within ancestry groups. Three loci - 2p12 (rs62164740, p = 6.27e-07), 10q22.2 (rs150952246, p = 3.14e-07), and 10q24.32 (rs118107597, p = 8.21e-07) are novel. Nine were in or near known OFC loci - PAX7, IRF6, FAM49A, DCAF4L2, 8q24.21, NTN1, WNT3-WNT9B, TANC2, and RHPN2. The majority of the associations were observed only in the combined sample, European, and Central and South American groups. We investigated whether the observed differences in association strength were (a) purely due to sample sizes, (b) due to systematic allele frequency difference at the population level, or (c) due to the fact certain OFC-causing variants confer different amounts of risk depending on ancestral origin, by comparing effect sizes to observed allele frequencies of the effect allele in our ancestry-based groups. While some of the associations differ due to systematic differences in allele frequencies between groups, others show variation in effect size despite similar frequencies across ancestry groups.

Role of B lymphocytes in the infarcted mass in patients with acute myocardial infarction

Introduction: Almost 20% of patients with acute myocardial infarction (MI) develop heart failure, even when early reperfused [1]. Left ventricular remodeling seems related to the size of myocardial infarction and timely reperfusion, as well as to the inflammatory responses and residual ischemia [2]. Experimental studies suggested that B lymphocytes may influence the myocardial infarcted mass [3], although there are few data about the role of these cells in humans. Furthermore, a possible atheroprotective role for B1 lymphocytes has been proposed based on the production of interleukin 10 (IL-10) and natural antibodies, which may switch the proinflammatory response to more appropriate healing, promoting cell recovery and the clearance of apoptotic cellular debris [4]. On the other hand, classic B lymphocytes or B2 cells are linked to progression of atherosclerosis, possibly by their interaction with CD4+ T lymphocytes [4]. In 2011, Griffin and colleagues proposed CD19+CD20+CD43+CD70- lymphocyte cells as the human B1 phenotype, and these cells spontaneously produced IgM and IL-10 [5]. However, according to the presence or absence of the CD11b on the surface of these cells, the capacity of IgM production and activation Stem cells in blood marrow differentiate in T or B lymphocyte, according to the presence of CD3 or CD19, respectively. Lymphocyte final maturation takes place in thymus for T cells; or in spleen and lymphatic tissue for classic B cells. B1 lymphocytes are well described in experimental studies. These cells are notorious for their capacity of spontaneous production of IgM and according to the presence of the CD11b, two distinct subtypes are recognized: CD11b- B1 lymphocytes, producing IgM, and CD11b+ B1 lymphocytes, related to the expansion of CD4+ T lymphocytes.

Potentiation of Antibiotic Activity by a Meldrum's Acid Arylamino Methylene Derivative against Multidrug-Resistant Bacterial Strains.

This study aimed to evaluate the intrinsic antibacterial activity and antibiotic-enhancing effect of an arylamino methylene derivative (MAD) in association with fluoroquinolones. The antibacterial activity against multiresistant Pseudomonas aeruginosa, Staphylococcus aureus and Escherichia coli was analyzed by determining the minimum inhibitory concentration (MIC) using the broth micro dilution method. A reduction in the MIC of the fluoroquinolones against strains treated simultaneously with the MAD was interpreted as an enhanced antibiotic activity. While the MAD exhibited no clinically effective action (MIC ≥ 1.024 µg/mL), it was found to significantly potentiate the activity of norfloxacin, ofloxacin and lomefloxacin against all the strains, which may be related to structural similarities between the MAD and quinolones. Our findings suggest that Meldrum's acid arylamino derivatives may represent promising molecules in the elaboration of new drugs to reverse resistance to fluoroquinolones.

Sticholysins, pore-forming proteins from a marine anemone can induce maturation of dendritic cells through a TLR4 dependent-pathway.

Sticholysins (Sts) I and II (StI and StII) are pore-forming proteins (PFPs), purified from the Caribbean Sea anemone Stichodactyla helianthus. StII encapsulated into liposomes induces a robust antigen-specific cytotoxic CD8+ T lymphocytes (CTL) response and in its free form the maturation of bone marrow-derived dendritic cells (BM-DCs). It is probable that the latter is partially supporting in part the immunomodulatory effect on the CTL response induced by StII-containing liposomes. In the present work, we demonstrate that the StII's ability of inducing maturation of BM-DCs is also shared by StI, an isoform of StII. Using heat-denatured Sts we observed a significant reduction in the up-regulation of maturation markers indicating that both PFP's ability to promote maturation of BM-DCs is dependent on their conformational characteristics. StII-mediated DC maturation was abrogated in BM-DCs from toll-like receptor (TLR) 4 and myeloid differentiation primary response gene 88 (MyD88)-knockout mice but not in cells from TLR2-knockout mice. Furthermore, the antigen-specific CTL response induced by StII-containing liposomes was reduced in TLR4-knockout mice. These results indicate that StII, and probably by extension StI, has the ability to induce maturation of DCs through a TLR4/MyD88-dependent pathway, and that this activation contributes to the CTL response generated by StII-containing liposomes.