M. tuberculosis Reprograms Hematopoietic Stem Cells to Limit Myelopoiesis and Impair Trained Immunity.

A greater understanding of hematopoietic stem cell (HSC) regulation is required for dissecting protective versus detrimental immunity to pathogens that cause chronic infections such as Mycobacterium tuberculosis (Mtb). We have shown that systemic administration of Bacille Calmette-Guérin (BCG) or ß-glucan reprograms HSCs in the bone marrow (BM) via a type II interferon (IFN-II) or interleukin-1 (IL1) response, respectively, which confers protective trained immunity against Mtb. Here, we demonstrate that, unlike BCG or ß-glucan, Mtb reprograms HSCs via an IFN-I response that suppresses myelopoiesis and impairs development of protective trained immunity to Mtb. Mechanistically, IFN-I signaling dysregulates iron metabolism, depolarizes mitochondrial membrane potential, and induces cell death specifically in myeloid progenitors. Additionally, activation of the IFN-I/iron axis in HSCs impairs trained immunity to Mtb infection. These results identify an unanticipated immune evasion strategy of Mtb in the BM that controls the magnitude and intrinsic anti-microbial capacity of innate immunity to infection.

Metabolic Adaptation Establishes Disease Tolerance to Sepsis.

Sepsis is an often lethal syndrome resulting from maladaptive immune and metabolic responses to infection, compromising host homeostasis. Disease tolerance is a defense strategy against infection that preserves host homeostasis without exerting a direct negative impact on pathogens. Here, we demonstrate that induction of the iron-sequestering ferritin H chain (FTH) in response to polymicrobial infections is critical to establish disease tolerance to sepsis. The protective effect of FTH is exerted via a mechanism that counters iron-driven oxidative inhibition of the liver glucose-6-phosphatase (G6Pase), and in doing so, sustains endogenous glucose production via liver gluconeogenesis. This is required to prevent the development of hypoglycemia that otherwise compromises disease tolerance to sepsis. FTH overexpression or ferritin administration establish disease tolerance therapeutically. In conclusion, disease tolerance to sepsis relies on a crosstalk between adaptive responses controlling iron and glucose metabolism, required to maintain blood glucose within a physiologic range compatible with host survival.

Ferritin heavy chain supports stability and function of the regulatory T cell lineage.

Regulatory T (TREG) cells develop via a program orchestrated by the transcription factor forkhead box protein P3 (FOXP3). Maintenance of the TREG cell lineage relies on sustained FOXP3 transcription via a mechanism involving demethylation of cytosine-phosphate-guanine (CpG)-rich elements at conserved non-coding sequences (CNS) in the FOXP3 locus. This cytosine demethylation is catalyzed by the ten-eleven translocation (TET) family of dioxygenases, and it involves a redox reaction that uses iron (Fe) as an essential cofactor. Here, we establish that human and mouse TREG cells express Fe-regulatory genes, including that encoding ferritin heavy chain (FTH), at relatively high levels compared to conventional T helper cells. We show that FTH expression in TREG cells is essential for immune homeostasis. Mechanistically, FTH supports TET-catalyzed demethylation of CpG-rich sequences CNS1 and 2 in the FOXP3 locus, thereby promoting FOXP3 transcription and TREG cell stability. This process, which is essential for TREG lineage stability and function, limits the severity of autoimmune neuroinflammation and infectious diseases, and favors tumor progression. These findings suggest that the regulation of intracellular iron by FTH is a stable property of TREG cells that supports immune homeostasis and limits the pathological outcomes of immune-mediated inflammation.

Coumarin-Based Compounds as Inhibitors of Tyrosinase/Tyrosine Hydroxylase: Synthesis, Kinetic Studies, and In Silico Approaches.

Cancer represents the main cause of morbidity and mortality worldwide, constituting a serious health problem. In this context, melanoma represents the most aggressive and fatal type of skin cancer, with death rates increasing every year. Scientific efforts have been addressed to the development of inhibitors targeting the tyrosinase enzyme as potential anti-melanoma agents due to the importance of this enzyme in melanogenesis biosynthesis. Coumarin-based compounds have shown potential activity as anti-melanoma agents and tyrosinase inhibitors. In this study, coumarin-based derivatives were designed, synthesized, and experimentally evaluated upon tyrosinase. Compound FN-19, a coumarin-thiosemicarbazone analog, exhibited potent anti-tyrosinase activity, with an IC50 value of 42.16 ± 5.16 µM, being more active than ascorbic acid and kojic acid, both reference inhibitors. The kinetic study showed that FN-19 acts as a mixed inhibitor. Still, for this compound, molecular dynamics (MD) simulations were performed to determine the stability of the complex with tyrosinase, generating RMSD, RMSF, and interaction plots. Additionally, docking studies were performed to elucidate the binding pose at the tyrosinase, suggesting that the hydroxyl group of coumarin derivative performs coordinate bonds (bidentate) with the copper(II) ions at distances ranging from 2.09 to 2.61 Å. Then, MM/PBSA calculations revealed that van der Waals interactions are the most relevant intermolecular forces for complex stabilization. Furthermore, it was observed that FN-19 has a binding energy (ΔEMM) value similar to tropolone, a tyrosinase inhibitor. Therefore, the data obtained in this study will be useful for designing and developing novel coumarin-based analogs targeting the tyrosinase enzyme.

Morphophysiological alterations in fruit-eating bats after oral exposure to deltamethrin.

Deltamethrin (DTM) is a synthetic pyrethroid widely used in the cultivation and management of several crops due to its insecticidal action. Application to crops of pyrethroids such as DTM can result in the exposure of water and fruit consumed by fruit bats having a high pyrethroid content which may be harmful. Therefore the objective of this study was to evaluate the effects of short-term oral exposure of the fruit-eating bats (Artibeus lituratus) to two concentrations of DTM (0.02 and 0.04 mg/kg of papaya) on histopathology of the intestine, liver and kidney. The intestine of the animals exposed to both concentrations showed inflammatory infiltrate, degeneration, necrosis and goblet cell hyperplasia as the most frequent pathologies. Besides, the acid mucins showed an increase in the frequency of non-viable cells. The liver showed hepatocyte vacuolizatio and nuclear enlargement, as well as inflammatory infiltrate and steatosis. The kidneys of the exposed animals showed and inflammatory infiltrate, benign nephrosclerosis, vacuolization and necrosis. Also, DTM reduced nitric oxide synthesis, decreased glomerular diameter and increased glycogen percentage in the proximal tubules. Our results suggest that acute exposure to DTM at low concentrations has the potential to induce pronounced histopathological changes in vital organs, such as intestine, liver and kidney of fruit-eating bats.

Ultra-processed food intake is associated with children and adolescents with congenital heart disease clustered by high cardiovascular risk factors.

The excessive intake of ultra-processed foods (UPF) is associated with an increase in cardiovascular risk. However, the effect of UPF intake on cardiovascular health in children and adolescents with congenital heart disease (CHD) is unknown. The aim of the present study was to describe UPF intake and evaluate associations with isolated cardiovascular risk factors and children and adolescents with CHD clustered by cardiovascular risk factors. A cross-sectional study was conducted involving 232 children and adolescents with CHD. Dietary intake was assessed using three 24-hour recalls. UPFs were categorized using the NOVA classification. The cardiovascular risk factors evaluated were central adiposity, elevated high-sensitivity C-reactive protein (hs-CRP) and subclinical atherosclerosis. The clustering of cardiovascular risk factors (waist circumference, hs-CRP and carotid intima-media thickness) was performed, allocating the participants to two groups (high versus low cardiovascular risk). UPFs contributed 40.69% (SD 6.21) to total energy intake. The main UPF groups were ready-to-eat and take-away/fast foods (22.2% energy from UPFs). The multivariable logistic regression revealed that an absolute increase of 10% in UPF intake (OR=1.90; 95% CI: 1.01;3.58) was associated with central adiposity. An absolute increase of 10% in UPF intake (OR=3.77; 95% CI: 1.80;7.87) was also associated with children and adolescents with CHD clustered by high cardiovascular risk after adjusting for confounding factors. Our findings demonstrate that UPF intake should be considered a modifiable risk factor for obesity and its cardiovascular consequences in children and adolescents with CHD.

Protective immunity triggered by ectonucleoside triphosphate diphosphohydrolase-based biopharmaceuticals attenuates cardiac parasitism and prevents mortality in Trypanosoma cruzi infection.

Chagas disease is a potentially fatal infection in 21 endemic Latin America countries for which the effectiveness of reference antiparasitic chemotherapy is limited. Thus, we developed three biopharmaceuticals and evaluated the effectiveness of different immunization strategies (recombinant protein NTPDase-1 [rNTPDase-1], DNA plasmid encoding Trypanosoma cruzi NTPDase-1 [TcNTPDase-1] and DNA-NTPDase-1 prime/rNTPDase-1 boost [Prime-boost]) based on the surface ecto-nucleoside triphosphate diphosphohydrolase (ecto-NTPDase) enzyme of T. cruzi in animals challenged with a virulent strain (Y) of this parasite. BALB/c mice were immunized three times at 30 days intervals, challenged with T. cruzi 15 days after the last immunization, and euthanized 30 days after T. cruzi challenge. Our results showed limited polarization of specific anti-ecto-NTPDase immunoglobulins in mice receiving both immunization protocols. Conversely, the Prime-boost strategy stimulated the Th1 protective phenotype, upregulating TNF-α and downregulating IL-10 production while increasing the activation/distribution of CD3+/CD8+, CD4+/CD44hi and CD8+/CD44hi/CD62L cells in immunized and infected mice. Furthermore, IL-6 and IL10 levels were reduced, while the distribution of CD4+/CD44hi and CD3+/CD8+ cells was increased from rNTPDase-1 and DNA-NTPDase1-based immunization strategies. Animals receiving DNA-NTPDase1 and Prime-boost protocols before T. cruzi challenged exhibited an enhanced immunological response associated with IL-17 upregulation and remarkable downregulation of heart parasitism (T. cruzi DNA) and mortality. These findings indicated that NTPDase-1 with Prime-boost strategy induced a protective and sustained Th17 response, enhancing host resistance against T. cruzi. Thus, ecto-NTPDase is a potentially relevant and applicable in the development of biopharmaceuticals with greater immunoprophylactic potential for Chagas disease.

Renal control of disease tolerance to malaria.

Malaria, the disease caused by Plasmodium spp. infection, remains a major global cause of morbidity and mortality. Host protection from malaria relies on immune-driven resistance mechanisms that kill Plasmodium However, these mechanisms are not sufficient per se to avoid the development of severe forms of disease. This is accomplished instead via the establishment of disease tolerance to malaria, a defense strategy that does not target Plasmodium directly. Here we demonstrate that the establishment of disease tolerance to malaria relies on a tissue damage-control mechanism that operates specifically in renal proximal tubule epithelial cells (RPTEC). This protective response relies on the induction of heme oxygenase-1 (HMOX1; HO-1) and ferritin H chain (FTH) via a mechanism that involves the transcription-factor nuclear-factor E2-related factor-2 (NRF2). As it accumulates in plasma and urine during the blood stage of Plasmodium infection, labile heme is detoxified in RPTEC by HO-1 and FTH, preventing the development of acute kidney injury, a clinical hallmark of severe malaria.

Is There a Connection between the Metabolism of Copper, Sulfur, and Molybdenum in Alzheimer's Disease? New Insights on Disease Etiology.

Alzheimer's disease (AD) and other forms of dementia was ranked 3rd in both the Americas and Europe in 2019 in a World Health Organization (WHO) publication listing the leading causes of death and disability worldwide. Copper (Cu) imbalance has been reported in AD and increasing evidence suggests metal imbalance, including molybdenum (Mo), as a potential link with AD occurrence.We conducted an extensive literature review of the last 60 years of research on AD and its relationship with Cu, sulfur (S), and Mo at out of range levels.Weanalyzed the interactions among metallic elements' metabolisms;Cu and Mo are biological antagonists, Mo is a sulfite oxidase and xanthine oxidase co-factor, and their low activities impair S metabolism and reduce uric acid, respectively. We found significant evidence in the literature of a new potential mechanism linking Cu imbalance to Mo and S abnormalities in AD etiology: under certain circumstances, the accumulation of Cu not bound to ceruloplasmin might affect the transport of Mo outside the blood vessels, causing a mild Mo deficiency that might lowerthe activity of Mo and S enzymes essential for neuronal activity. The current review provides an updated discussion of the plausible mechanisms combining Cu, S, and Mo alterations in AD.

Venom Profiling of the Insular Species Bothrops alcatraz: Characterization of Proteome, Glycoproteome, and N-Terminome Using Terminal Amine Isotopic Labeling of Substrates.

Bothrops alcatraz, a species endemic to Alcatrazes Islands, is regarded as critically endangered due to its small area of occurrence and the declining quality of its habitat. We recently reported the identification of N-glycans attached to toxins of Bothrops species, showing similar compositions in venoms of the B. jararaca complex (B. jararaca, B. insularis, and B. alcatraz). Here, we characterized B. alcatraz venom using electrophoretic, proteomic, and glycoproteomic approaches. Electrophoresis showed that B. alcatraz venom differs from B. jararaca and B. insularis; however, N-glycan removal revealed similarities between them, indicating that the occupation of N-glycosylation sites contributes to interspecies variability in the B. jararaca complex. Metalloproteinase was the major toxin class identified in the B. alcatraz venom proteome followed by serine proteinase and C-type lectin, and overall, the adult B. alcatraz venom resembles that of B. jararaca juvenile specimens. The comparative glycoproteomic analysis of B. alcatraz venom with B. jararaca and B. insularis indicated that there may be differences in the utilization of N-glycosylation motifs among their different toxin classes. Furthermore, we prospected for the first time the N-terminome of a snake venom using the terminal amine isotopic labeling of substrates (TAILS) approach and report the presence of ∼30% of N-termini corresponding to truncated toxin forms and ∼37% N-terminal sequences blocked by pyroglutamic acid in B. alcatraz venom. These findings underscore a low correlation between venom gland transcriptomes and proteomes and support the view that post-translational processes play a major role in shaping venom phenotypes.

Computer-aided design of 1,4-naphthoquinone-based inhibitors targeting cruzain and rhodesain cysteine proteases.

Chagas disease and Human African Trypanosomiasis (HAT) are caused by Trypanosoma cruzi and T. brucei parasites, respectively. Cruzain (CRZ) and Rhodesain (RhD) are cysteine proteases that share 70% of identity and play vital functions in these parasites. These macromolecules represent promising targets for designing new inhibitors. In this context, 26 CRZ and 5 RhD 3D-structures were evaluated by molecular redocking to identify the most accurate one to be utilized as a target. Posteriorly, a virtual screening of a library containing 120 small natural and nature-based compounds was performed on both of them. In total, 14 naphthoquinone-based analogs were identified, synthesized, and biologically evaluated. In total, five compounds were active against RhD, being three of them also active on CRZ. A derivative of 1,4-naphthoquinonepyridin-2-ylsulfonamide was found to be the most active molecule, exhibiting IC50 values of 6.3 and 1.8 µM for CRZ and RhD, respectively. Dynamic simulations at 100 ns demonstrated good stability and do not alter the targets' structures. MM-PBSA calculations revealed that it presents a higher affinity for RhD (-25.3 Kcal mol-1) than CRZ, in which van der Waals interactions were more relevant. A mechanistic hypothesis (via C3-Michael-addition reaction) involving a covalent mode of inhibition for this compound towards RhD was investigated by covalent molecular docking and DFT B3LYP/6-31 + G* calculations, exhibiting a low activation energy (ΔG‡) and providing a stable product (ΔG), with values of 7.78 and - 39.72 Kcal mol-1, respectively; similar to data found in the literature. Nevertheless, a reversibility assay by dilution revealed that JN-11 is a time-dependent and reversible inhibitor. Finally, this study applies modern computer-aided techniques to identify promising inhibitors from a well-known chemical class of natural products. Then, this work could inspire other future studies in the field, being useful for designing potent naphthoquinones as RhD inhibitors.

Dietary patterns are associated with central adiposity and carotid intima-media thickness in children and adolescents with congenital heart disease.

PURPOSE: Unhealthy dietary patterns (DP) in childhood are associated with cardiovascular disease in adulthood. DP in children and adolescents with congenital heart disease (CHD) are unknown. The aims of this study were to describe DPs of children and adolescents with CHD and to evaluate their associations with central adiposity, high-sensitivity C-reactive protein (hs-CRP) and carotid intima-media thickness (cIMT). METHODS: A cross-sectional study including 232 children and adolescents with CHD. Dietary data were based on three 24-h dietary recalls. Central adiposity was evaluated by waist circumference. hs-CRPs were determined by nephelometry. The cIMT was measured using ultrasound. DPs were identified using principal component analysis. Data were examined using logistic and linear regressions. RESULTS: Six DPs were identified. In multivariable-adjusted analysis, unhealthy DP (high intake of poultry, red meat, cold cuts and processed meats, soft drinks and sweetened beverages) and healthy DP (high intake of fish, eggs, bread, beans, tubers and roots, fruit and fruit juice) were associated with increased and decreased odds of central adiposity, respectively (Odds ratio (OR): 2.10; 95% confidence interval (95% CI) 1.09; 4.02; OR: 0.48 95% CI 0.24; 0.93). Besides, low-fat dairy DP (high intake of low-fat milk and dairy, mixed dishes, ultra-processed breads, candy and chocolate) was inversely associated with cIMT (ß: - 0.024; 95% CI - 0.04; - 0.01). CONCLUSION: Unhealthy DP seems to increase the risk of central adiposity, while the healthy DP seems to decrease the risk of central adiposity. Still, low-fat dairy DP was inversely associated with cIMT. These findings may be helpful to develop nutrition recommendations for early cardiovascular disease prevention in children and adolescents with CHD.

Subclinical atherosclerosis in children and adolescents with congenital heart disease.

BACKGROUND: Subclinical atherosclerosis in childhood can be evaluated by carotid intima-media thickness, which is considered a surrogate marker for atherosclerotic disease in adulthood. The aims of this study were to evaluate carotid intima-media thickness and, to investigate associated factors. METHODS: Cross-sectional study with children and adolescents with congenital heart disease (CHD). Socio-demographic and clinical characteristics were assessed. Subclinical atherosclerosis was evaluated by carotid intima-media thickness. Cardiovascular risk factors, such as physical activity, screen time, passive smoke, systolic and diastolic blood pressure, waist circumference, dietary intake, lipid parameters, glycaemia, and C-reactive protein, were also assessed. Factors associated with carotid intima-media thickness were analysed using multiple logistic regression. RESULTS: The mean carotid intima-media thickness was 0.518 mm and 46.7% had subclinical atherosclerosis (carotid intima-media thickness ≥ 97th percentile). After adjusting for confounding factors, cyanotic CHD (odds ratio: 0.40; 95% confidence interval: 0.20; 0.78), cardiac surgery (odds ratio: 3.17; 95% confidence interval: 1.35; 7.48), and be hospitalised to treat infections (odds ratio: 1.92; 95% confidence interval: 1.04; 3.54) were associated with subclinical atherosclerosis. CONCLUSION: Clinical characteristics related to CHD were associated with subclinical atherosclerosis. This finding suggests that the presence of CHD itself is a risk factor for subclinical atherosclerosis. Therefore, the screen and control of modifiable cardiovascular risk factors should be made early and intensively to prevent atherosclerosis.

Interleukin-1 promotes autoimmune neuroinflammation by suppressing endothelial heme oxygenase-1 at the blood-brain barrier.

The proinflammatory cytokine interleukin 1 (IL-1) is crucially involved in the pathogenesis of multiple sclerosis (MS) and its animal model experimental autoimmune encephalomyelitis (EAE). Herein, we studied the role of IL-1 signaling in blood-brain barrier (BBB) endothelial cells (ECs), astrocytes and microglia for EAE development, using mice with the conditional deletion of its signaling receptor IL-1R1. We found that IL-1 signaling in microglia and astrocytes is redundant for the development of EAE, whereas the IL-1R1 deletion in BBB-ECs markedly ameliorated disease severity. IL-1 signaling in BBB-ECs upregulated the expression of the adhesion molecules Vcam-1, Icam-1 and the chemokine receptor Darc, all of which have been previously shown to promote CNS-specific inflammation. In contrast, IL-1R1 signaling suppressed the expression of the stress-responsive heme catabolizing enzyme heme oxygenase-1 (HO-1) in BBB-ECs, promoting disease progression via a mechanism associated with deregulated expression of the IL-1-responsive genes Vcam1, Icam1 and Ackr1 (Darc). Mechanistically, our data emphasize a functional crosstalk of BBB-EC IL-1 signaling and HO-1, controlling the transcription of downstream proinflammatory genes promoting the pathogenesis of autoimmune neuroinflammation.

Druggable targets from coronaviruses for designing new antiviral drugs.

Severe respiratory infections were highlighted in the SARS-CoV outbreak in 2002, as well as MERS-CoV, in 2012. Recently, the novel CoV (COVID-19) has led to severe respiratory damage to humans and deaths in Asia, Europe, and Americas, which allowed the WHO to declare the pandemic state. Notwithstanding all impacts caused by Coronaviruses, it is evident that the development of new antiviral agents is an unmet need. In this review, we provide a complete compilation of all potential antiviral agents targeting macromolecular structures from these Coronaviruses (Coronaviridae), providing a medicinal chemistry viewpoint that could be useful for designing new therapeutic agents.

Structures of N-Glycans of Bothrops Venoms Revealed as Molecular Signatures that Contribute to Venom Phenotype in Viperid Snakes.

The complexity of snake venoms has long been investigated to explore a myriad of biologically active proteins and peptides that are used for immobilizing or killing prey, and are responsible for the pathological effects observed on envenomation. Glycosylation is the main post-translational modification (PTM) of viperid venoms but currently there is little understanding of how protein glycosylation impacts the variation of venom proteomes. We have previously reported that Bothrops venom glycoproteomes contain a core of components that markedly define their composition and parallel their phylogenetic classification. Here we extend those observations to eight Bothrops species evaluating the N-glycomes by LC-MS as assigned cartoon structures and detailing those structures separately as methylated analogs using ion-trap mass spectrometry (MSn). Following ion disassembly through multiple steps provided sequence and linkage isomeric details that characterized 52 unique compositions in Bothrops venoms. These occurred as 60 structures, of which 26 were identified in the venoms of the Jararaca Complex (B. alcatraz, B. insularis, and B. jararaca), 20 in B. erythromelas, B. jararacussu, B. moojeni and B. neuwiedi venoms, and 22 in B. cotiara venom. Further, quantitative analysis of these N-glycans showed variable relative abundances in the venoms. For the first time a comprehensive set of N-glycan structures present in snake venoms are defined. Despite the fact that glycosylation is not template-defined, the N-glycomes of these venoms mirror the phylogeny cladograms of South American bothropoid snakes reported in studies on morphological, molecular data and feeding habits, exhibiting distinct molecular signatures for each venom. Considering the complexity of N-glycan moieties generally found in glycoproteins, characterized by different degrees of branching, isomer structures, and variable abundances, our findings point to these factors as another level of complexity in Bothrops venoms, features that could dramatically contribute to their distinct biological activities.

[Microcephaly and central nervous system findings associated with congenital Zika virus and other infectious etiologies in the state of Rio de Janeiro: crosssectional study, 2015 a 2017Microcefalia y alteraciones del sistema nervioso central relacionadas con la infección congénita por el virus del Zika y otras etiologías infecciosas en el Estado de Río de Janeiro: estudio transversal, 2015-2017]. / Microcefalia e alterações do sistema nervoso central relacionadas à infecção congênita pelo vírus Zika e outras etiologias infecciosas no estado do Rio de Janeiro: estudo transversal, 2015 a 2017.

OBJECTIVE: To describe the clinical and epidemiological profile of cases with confirmed microcephaly or central nervous system (CNS) findings associated with congenital Zika virus infection and other infectious etiologies in the state of Rio de Janeiro, Brazil, from November 2015 to July 2017. METHOD: A cross-sectional study was performed with 298 cases (as defined by the Ministry of Health) communicated to the Rio de Janeiro State Department of Health in the study period. Demographic, epidemiological, clinical, radiological, and laboratory variables were assessed. Descriptive bivariate and multivariable logistic regression analysis was used to determine the association between specific factors and death outcome. RESULTS: The median age of mothers was 24 years; 30.9% reported fever and 64.8% reported a rash during pregnancy. The median head circumference at birth was 29 cm, and median birth weight was 2 635 g. An etiological diagnosis of congenital Zika was made in 46.0%, whereas 13.8% were diagnosed with syphilis, toxoplasmosis, rubella, cytomegalovirus, and herpes simplex infections (STORCH), with predominance of syphilis, and 40.3% had an unspecified infectious agent. CNS findings other than microcephaly were observed in 88.3%, especially intracranial calcifications, ventriculomegaly, and brain atrophy. Overall lethality was 7.0% - 19.0% in laboratory confirmed Zika cases and 22.2% in toxoplasmosis cases. Multivariable analysis revealed birth weight as the main predictor of death. CONCLUSIONS: Despite the Zika epidemic, 13.8% of the studied cases were diagnosed with STORCH. The lethality and high frequency of neurological findings beyond microcephaly reflect severe infection, with impact on families and health care system.

OBJETIVO: Describir el perfil clínico-epidemiológico de los casos confirmados de microcefalia y de alteraciones del sistema nervioso central (SNC) relacionados con la infección congénita por el virus del Zika y otras etiologías infecciosas en el Estado de Río de Janeiro en el período comprendido entre noviembre del 2015 y julio del 2017. MÉTODOS: Se realizó un estudio transversal de 298 casos (según la definición del Ministerio de Salud) notificados a la Secretaría de Estado de Salud de Río de Janeiro en el período objeto de estudio. Se analizaron variables demográficas, epidemiológicas, clínicas, radiológicas y de laboratorio, con un análisis estadístico descriptivo bivariado y de regresión logística múltiple para estudio de los factores relacionados con la defunción. RESULTADOS: La edad mediana de las madres fue de 24 años; un 30,9% informó fiebre y un 64,8%, exantema durante la gestación. La mediana del perímetro cefálico al nacer fue de 29 cm y la del peso, de 2635 g. El diagnóstico etiológico fue de infección congénita por el virus del Zika en un 46,0%; sífilis, toxoplasmosis, rubéola, infección por citomegalovirus e infección por el virus del herpes simple (STORCH) en un 13,8%, con predominio de sífilis; e infección por un agente infeccioso no definido en un 40,3%. Se describieron alteraciones del SNC diferentes de microcefalia en un 88,3%, con predominio de calcificaciones cerebrales, ventriculomegalia y atrofia cerebral. La letalidad total alcanzó 7,0%; se confirmaron en el laboratorio 19,0% de los casos de infección por el virus del Zika y 22,2% de los casos de toxoplasmosis. En el análisis de regresión logística múltiple, el peso al nacer fue el principal pronóstico de defunción. CONCLUSIONES: A pesar de la epidemia de la infección por el virus del Zika, 13,8% de los casos fueron causados por STORCH. La letalidad y la elevada presencia de malformaciones neurológicas, además de microcefalia, muestran la gravedad de la infección y sus repercusiones para las familias y para el sistema de salud.

Exposure to deltamethrin induces oxidative stress and decreases of energy reserve in tissues of the Neotropical fruit-eating bat Artibeus lituratus.

Deltamethrin (DTM) is a synthetic pyrethroid insecticide highly used by farmers and home users. This pesticide has lipophilic properties that facilitate a high absorption and can cause toxicity in non-target organisms. During foraging, the fruit-eating bats Artibeus lituratus are exposed to pesticides. However, the knowledge of the toxicity of pesticides on the physiology of bats is relatively scarce. This study aimed to check the toxicity of short-term exposure to low concentration of DTM on fruit-eating bat A. lituratus. After seven days of exposure to two doses of DTM (0.02 and 0.04mg/kg of papaya), the fruit bats showed an increase in the enzyme aspartate aminotransferase, alanine aminotransferase, and hyperglycemia. The liver and pectoral muscle presented oxidative stress. In the liver, the hydrogen peroxide (H2O2) and nitric oxide (NO) were increased as well as the antioxidant glutathione (GSH), the activity of glutathione S-transferase (GST), superoxide dismutase (SOD) and catalase (CAT) but in a lesser extent. Yet, total lipids were increased while hepatic glycogen content is reduced. The pectoral muscle showed NO, SOD, CAT, malondialdehyde (MDA), and carbonyl increased protein levels in both concentrations of DTM. All these results show that low doses of DTM can cause hepatic and muscular toxicity and induce changes in carbohydrate metabolism. Physiological changes caused by exposure to DTM in bats may have direct consequences in flight capacity, reproduction, and metabolism of these animals.

Construction of recombinant Kluyveromyces marxianus UFV-3 to express dengue virus type 1 nonstructural protein 1 (NS1).

The yeast Kluyveromyces marxianus is a convenient host for industrial synthesis of biomolecules. However, despite its potential, there are few studies reporting the expression of heterologous proteins using this yeast. Here, we report expression of a dengue virus protein in K. marxianus for the first time. The dengue virus type 1 nonstructural protein 1 (NS1) was integrated into the K. marxianus UFV-3 genome at the LAC4 locus using an adapted integrative vector designed for high-level expression of recombinant protein in Kluyveromyces lactis. The NS1 gene sequence was codon-optimized to increase the level of protein expression in yeast. The synthetic gene was cloned in frame with K. lactis α-mating factor signal peptide, and the recombinant plasmid obtained was used to transform K. marxianus UFV-3 by electroporation. The transformed cells, selected in yeast extract peptone dextrose containing 200 µg mL(-1) Geneticin, were mitotically stable. Analysis of recombinant strains by RT-PCR and protein detection using blot analysis confirmed both transcription and expression of extracellular NS1 polypeptide. After induction with galactose, the NS1 protein was analyzed by sodium dodecyl sulfate-PAGE and immunogenic detection. Protein production was investigated under two conditions: with galactose and biotin pulses at 24-h intervals during 96 h of induction and without galactose and biotin supplementation. Protease activity was not detected in post-growth medium. Our results indicate that recombinant K. marxianus is a good host for the production of dengue virus NS1 protein, which has potential for diagnostic applications.

Antigen production using heterologous expression of dengue virus-2 non-structural protein 1 (NS1) in Nicotiana tabacum (Havana) for immunodiagnostic purposes.

KEY MESSAGE: Expression of dengue-2 virus NS1 protein in Nicotiana tabacum plants for development of dengue immunodiagnostic kits. Dengue is one of the most important diseases caused by arboviruses in the world. A significant increase in its geographical distribution has been noticed over the last 20 years, with continuous transmission of several serotypes and emergence of the hemorrhagic fever in areas where the disease was previously not prevalent. Although the methodological processes for dengue diagnosis are in deep development and improvement, a limitation for the realization of dengue diagnostic tests is the difficulty of large-scale production of the antigen to be used in diagnostic tests. Due to this demand, the purpose of this study was to obtain the non-structural protein 1 (NS1) from dengue-2 serotype by heterologous expression in Nicotiana tabacum (Havana). After confirmation of the NS1 protein gene integration in the plant genome, the heterologous protein was characterized using SDS-PAGE and immunoblotting. In an immunoenzymatic test, the recombinant NS1 protein presents an antigen potential for development of dengue immunodiagnostic kits.