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1.
Vaccine ; 42(23): 126220, 2024 Aug 24.
Article de Anglais | MEDLINE | ID: mdl-39182314

RÉSUMÉ

Sheep farming contributes to the socioeconomic development of small and medium-scale livestock farmers. However, several factors can hinder successful animal production, as is the case for infectious diseases, such as the one caused by Corynebacterium pseudotuberculosis, known as caseous lymphadenitis (CLA). CLA has >90% prevalence in Brazilian herds and antibiotic treatment is not effective, consequently causing significant economic losses to farmers. Given the above, effective vaccines need to be developed to prevent this disease. This study aimed to evaluate the adjuvant activity of the lipid extract from the macroalgae Iridaea cordata as a candidate for developing an effective vaccine formulation. For such, four groups of six sheep each were inoculated with sterile 0.9% saline solution (G1), rCP01850 (G2), rCP01850 + I. cordata (G3), and rCP01850 + saponin (G4). Each sheep received two vaccine doses 30 days apart. Total IgG production levels significantly increased in experimental groups G3 and G4 on days 30, 60, and 90. On day 90, G3 showed higher total IgG production (p < 0.05) when compared to G4. When analyzing cytokine production, G3 was the only experimental group with significantly increased IFN-γ, IL-12, TNF-α, and IL-10 mRNA expression levels. Our results show the vaccine formulation containing rCP01850 adjuvanted with the I. cordata lipid extract elicited a Th1 immune response in sheep, indicating I. cordata lipid extract may be a promising adjuvant for developing an effective vaccine against infection caused by C. pseudotuberculosis.

2.
Anaerobe ; 89: 102895, 2024 Oct.
Article de Anglais | MEDLINE | ID: mdl-39122140

RÉSUMÉ

INTRODUCTION: Producing commercial bacterins/toxoids against Clostridium spp. is laborious and hazardous. Conversely, developing prototype vaccines using purified recombinant toxoids, though safe and effective, is both laborious and costly for application in production animals. OBJECTIVE: Considering that inactivated recombinant Escherichiacoli (bacterin) is a simple, cost-effective, and to be safe solution, we evaluated, for the first time, a pentavalent formulation of recombinant bacterins containing the alpha, beta, and epsilon toxins of Clostridiumperfringens and C and D neurotoxins of Clostridiumbotulinum in sheep. METHODS: Subcutaneously, 18 Texel sheep received two doses (200 µg of each antigen) of recombinant bacterin (n = 7) or purified recombinant antigens (n = 6) on days 0 and 28, while the control group (n = 5) did not receive an immunization. Sera samples from days 0 (before the 1st dose), 28 (before the 2nd dose), and 56, 84, and 112 were used for measuring IgG (indirect ELISA) and neutralizing antibodies (mouse serum neutralization). RESULTS: Both formulations induced significant levels of IgG against all five toxins (p < 0.05) up to day 112, with peaks at days 28 and 56 post-immunization. The expected booster effect occurred only for the botulinum toxins. The neutralizing antibody titers were satisfactory against ETX (≥2 IU/ml for both formulations) and BoNT-D [5 IU/ml (bacterin) and 10 IU/ml (purified)]. CONCLUSION: While adjustments are required, the recombinant bacterin platform holds great potential for polyvalent vaccines due to its straightforward, safe, and cost-effective production, establishing it as a user-friendly technology for the veterinary immunobiological industry.


Sujet(s)
Anticorps antibactériens , Anticorps neutralisants , Vaccins antibactériens , Botulisme , Entérotoxémie , Animaux , Botulisme/prévention et contrôle , Botulisme/médecine vétérinaire , Botulisme/immunologie , Ovis , Vaccins antibactériens/immunologie , Vaccins antibactériens/administration et posologie , Vaccins antibactériens/génétique , Anticorps antibactériens/sang , Entérotoxémie/prévention et contrôle , Entérotoxémie/immunologie , Anticorps neutralisants/sang , Anticorps neutralisants/immunologie , Maladies des ovins/prévention et contrôle , Maladies des ovins/immunologie , Maladies des ovins/microbiologie , Vaccins synthétiques/immunologie , Vaccins synthétiques/administration et posologie , Vaccins synthétiques/génétique , Immunoglobuline G/sang , Escherichia coli/génétique , Protéines recombinantes/immunologie , Protéines recombinantes/génétique , Femelle
3.
Anaerobe ; 89: 102902, 2024 Oct.
Article de Anglais | MEDLINE | ID: mdl-39187174

RÉSUMÉ

INTRODUCTION: Chickens with Necrotic Enteritis (NE), caused by Clostridium perfringens, exhibit acute and chronic symptoms that are difficult to diagnose, leading to significant economic losses. Vaccination is the best method for controlling and preventing NE. However, only two vaccines based on the CPA and NetB toxins have been commercialized, offering partial protection, highlighting the urgent need for more effective vaccines. OBJECTIVE: This review aimed to identify promising antigens for NE vaccine formulation and discuss factors affecting their effectiveness. METHODS: A systematic review using five scientific databases identified 30 eligible studies through the Rayyan tool, which were included for quality review. RESULTS: We identified 25 promising antigens, including CPA, NetB, FBA, ZMP, CnaA, FimA, and FimB, categorized by their role in disease pathogenesis. This review discusses the biochemical, physiological, and genetic traits of recombinant antigens used in vaccine prototypes, their expression systems, and immunization potential in chickens challenged with virulent C. perfringens strains. Market supply challenges, immunogenic potential, vaccine platforms, adjuvants, and factors related to vaccination schedules-such as administration routes, dosing intervals, and age at immunization-are also addressed. Additionally, the study notes that vaccine formulations tested under mild challenges may not offer adequate field-level protection due to issues replicating aggressive conditions, strain virulence loss, and varied methodologies. CONCLUSIONS: An ideal NE vaccine should incorporate multiple antigens, molecular adjuvants, and delivery systems via in ovo and oral routes. The review underscores the challenges in developing and validating NE vaccines and the urgent need for a standardized protocol to replicate aggressive challenges accurately.


Sujet(s)
Vaccins antibactériens , Poulets , Infections à Clostridium , Clostridium perfringens , Entérite , Maladies de la volaille , Animaux , Clostridium perfringens/immunologie , Clostridium perfringens/génétique , Entérite/prévention et contrôle , Entérite/médecine vétérinaire , Entérite/microbiologie , Entérite/immunologie , Vaccins antibactériens/immunologie , Vaccins antibactériens/administration et posologie , Maladies de la volaille/prévention et contrôle , Maladies de la volaille/microbiologie , Infections à Clostridium/prévention et contrôle , Infections à Clostridium/médecine vétérinaire , Infections à Clostridium/immunologie , Antigènes bactériens/immunologie , Développement de vaccin/méthodes , Vaccination/médecine vétérinaire , Vaccination/méthodes , Nécrose/médecine vétérinaire
4.
J Virol Methods ; 329: 114969, 2024 Sep.
Article de Anglais | MEDLINE | ID: mdl-38834144

RÉSUMÉ

The recent COVID-19 pandemic disclosed a critical shortage of diagnostic kits worldwide, emphasizing the urgency of utilizing all resources available for the development and production of diagnostic tests. Different heterologous protein expression systems can be employed for antigen production. This study assessed novel SARS-CoV-2 proteins produced by a transient expression system in Nicotiana benthamiana utilizing an infectious clone vector based on pepper ringspot virus (PepRSV). These proteins included the truncated S1-N protein (spike protein N-terminus residues 12-316) and antigen N (nucleocapsid residues 37-402). Two other distinct SARS-CoV-2 antigens expressed in Escherichia coli were evaluated: QCoV9 chimeric antigen protein (spike protein residues 449-711 and nucleocapsid protein residues 160-406) and QCoV7 truncated antigen (nucleocapsid residues 37-402). ELISAs using the four antigens individually and the same panel of samples were performed for the detection of anti-SARS-CoV-2 IgG antibodies. Sensitivity was evaluated using 816 samples from 351 COVID-19 patients hospitalized between 5 and 65 days after symptoms onset; specificity was tested using 195 samples collected before 2018, from domiciliary contacts of leprosy patients. Our findings demonstrated consistent test sensitivity, ranging from 85 % to 88 % with specificity of 97.5 %, regardless of the SARS-CoV2 antigen and the expression system used for production. Our results highlight the potential of plant expression systems as useful alternative platforms to produce recombinant antigens and for the development of diagnostic tests, particularly in resource-constrained settings.


Sujet(s)
Anticorps antiviraux , Antigènes viraux , COVID-19 , Test ELISA , Escherichia coli , Immunoglobuline G , Nicotiana , SARS-CoV-2 , Glycoprotéine de spicule des coronavirus , Escherichia coli/génétique , Escherichia coli/métabolisme , Humains , Nicotiana/génétique , Immunoglobuline G/sang , Test ELISA/méthodes , Anticorps antiviraux/sang , Anticorps antiviraux/immunologie , SARS-CoV-2/immunologie , SARS-CoV-2/génétique , Antigènes viraux/immunologie , Antigènes viraux/génétique , COVID-19/diagnostic , COVID-19/immunologie , Glycoprotéine de spicule des coronavirus/immunologie , Glycoprotéine de spicule des coronavirus/génétique , Dépistage sérologique de la COVID-19/méthodes , Sensibilité et spécificité , Protéines de la nucléocapside des coronavirus/immunologie , Protéines de la nucléocapside des coronavirus/génétique , Protéines recombinantes/génétique , Protéines recombinantes/immunologie , Adulte , Adulte d'âge moyen , Phosphoprotéines
5.
Sci Rep ; 14(1): 11176, 2024 05 15.
Article de Anglais | MEDLINE | ID: mdl-38750071

RÉSUMÉ

Multiple Myeloma (MM) is a hematological malignancy characterized by the clonal proliferation of plasma cells within the bone marrow. Diagnosing MM presents considerable challenges, involving the identification of plasma cells in cytology examinations on hematological slides. At present, this is still a time-consuming manual task and has high labor costs. These challenges have adverse implications, which rely heavily on medical professionals' expertise and experience. To tackle these challenges, we present an investigation using Artificial Intelligence, specifically a Machine Learning analysis of hematological slides with a Deep Neural Network (DNN), to support specialists during the process of diagnosing MM. In this sense, the contribution of this study is twofold: in addition to the trained model to diagnose MM, we also make available to the community a fully-curated hematological slide dataset with thousands of images of plasma cells. Taken together, the setup we established here is a framework that researchers and hospitals with limited resources can promptly use. Our contributions provide practical results that have been directly applied in the public health system in Brazil. Given the open-source nature of the project, we anticipate it will be used and extended to diagnose other malignancies.


Sujet(s)
Myélome multiple , Humains , Moelle osseuse/anatomopathologie , Brésil , Hématologie/méthodes , Apprentissage machine , Myélome multiple/diagnostic , Myélome multiple/anatomopathologie , , Plasmocytes/anatomopathologie
6.
J Med Chem ; 67(11): 8609-8629, 2024 Jun 13.
Article de Anglais | MEDLINE | ID: mdl-38780468

RÉSUMÉ

Vaccinia-related kinase 1 (VRK1) and the δ and ε isoforms of casein kinase 1 (CK1) are linked to various disease-relevant pathways. However, the lack of tool compounds for these kinases has significantly hampered our understanding of their cellular functions and therapeutic potential. Here, we describe the structure-based development of potent inhibitors of VRK1, a kinase highly expressed in various tumor types and crucial for cell proliferation and genome integrity. Kinome-wide profiling revealed that our compounds also inhibit CK1δ and CK1ε. We demonstrate that dihydropteridinones 35 and 36 mimic the cellular outcomes of VRK1 depletion. Complementary studies with existing CK1δ and CK1ε inhibitors suggest that these kinases may play overlapping roles in cell proliferation and genome instability. Together, our findings highlight the potential of VRK1 inhibition in treating p53-deficient tumors and possibly enhancing the efficacy of existing cancer therapies that target DNA stability or cell division.


Sujet(s)
Inhibiteurs de protéines kinases , Protein-Serine-Threonine Kinases , Ptéridines , Humains , Inhibiteurs de protéines kinases/pharmacologie , Inhibiteurs de protéines kinases/composition chimique , Inhibiteurs de protéines kinases/synthèse chimique , Protein-Serine-Threonine Kinases/antagonistes et inhibiteurs , Protein-Serine-Threonine Kinases/métabolisme , Ptéridines/pharmacologie , Ptéridines/composition chimique , Ptéridines/synthèse chimique , Protéines et peptides de signalisation intracellulaire/antagonistes et inhibiteurs , Protéines et peptides de signalisation intracellulaire/métabolisme , Prolifération cellulaire/effets des médicaments et des substances chimiques , Relation structure-activité , Casein Kinase Idelta/antagonistes et inhibiteurs , Casein Kinase Idelta/métabolisme , Caséine-kinase-1epsilon/antagonistes et inhibiteurs , Caséine-kinase-1epsilon/métabolisme , Lignée cellulaire tumorale
7.
Microb Pathog ; 189: 106596, 2024 Apr.
Article de Anglais | MEDLINE | ID: mdl-38395317

RÉSUMÉ

Botulism is a severe disease caused by potent botulinum neurotoxins (BoNTs) produced by Clostridium botulinum. This disease is associated with high-lethality outbreaks in cattle, which have been linked to the ingestion of preformed BoNT serotypes C and D, emphasizing the need for effective vaccines. The potency of current commercial toxoids (formaldehyde-inactivated BoNTs) is assured through tests in guinea pigs according to government regulatory guidelines, but their short-term immunity raises concerns. Recombinant vaccines containing the receptor-binding domain have demonstrated potential for eliciting robust protective immunity. Previous studies have demonstrated the safety and effectiveness of recombinant E. coli bacterin, eliciting high titers of neutralizing antibodies against C. botulinum and C. perfringens in target animal species. In this study, neutralizing antibody titers in cattle and the long-term immune response against BoNT/C and D were used to assess the efficacy of the oil-based adjuvant compared with that of the aluminum hydroxide adjuvant in cattle. The vaccine formulation containing Montanide™ ISA 50 yielded significantly higher titers of neutralizing antibody against BoNT/C and D (8.64 IU/mL and 9.6 IU/mL, respectively) and induced an immune response that lasted longer than the response induced by aluminum, extending between 30 and 60 days. This approach represents a straightforward, cost-effective strategy for recombinant E. coli bacterin, enhancing both the magnitude and duration of the immune response to botulism.


Sujet(s)
Toxines botuliniques , Botulisme , Clostridium botulinum , Bovins , Animaux , Cochons d'Inde , Botulisme/prévention et contrôle , Botulisme/médecine vétérinaire , Hydroxyde d'aluminium , Escherichia coli/génétique , Vaccins antibactériens/génétique , Toxines botuliniques/génétique , Clostridium botulinum/génétique , Adjuvants immunologiques , Anticorps neutralisants , Immunité , Anticorps antibactériens
8.
J Nutr Biochem ; 123: 109492, 2024 01.
Article de Anglais | MEDLINE | ID: mdl-37866427

RÉSUMÉ

Every year, thousands of children, particularly those under 5 years old, die because of cerebral malaria (CM). Following conventional treatment, approximately 25% of surviving individuals have lifelong severe neurocognitive sequelae. Therefore, improved conventional therapies or effective alternative therapies that prevent the severe infection are crucial. Omega-3 (Ω-3) polyunsaturated fatty acids (PUFAs) are known to have antioxidative and anti-inflammatory effects and protect against diverse neurological disorders, including Alzheimer's and Parkinson's diseases. However, little is known regarding the effects of Ω-3 PUFAs against parasitic infections. In this study, C57BL/6 mice received supplemental treatment of a fish oil rich in the Ω-3 PUFA, docosahexaenoic acid (DHA), which was started 15 days prior to infection with Plasmodium berghei ANKA and was maintained until the end of the study. Animals treated with the highest doses of DHA, 3.0 and 6.0 g/kg body weight, had 60 and 80% chance of survival, respectively, while all nontreated mice died by the 7th day postinfection due to CM. Furthermore, the parasite load during the critical period for CM development (5th to 11th day postinfection) was controlled in treated mice. However, after this period all animals developed high levels of parasitemia until the 20th day of infection. DHA treatment also effectively reduced blood-brain barrier (BBB) damage and brain edema and completely prevented brain hemorrhage and vascular occlusion. A strong anti-inflammatory profile was observed in the brains of DHA-treated mice, as well as, an increased number of neutrophil and reduced number of CD8+ T leukocytes in the spleen. Thus, this is the first study to demonstrate that the prophylactic use of DHA-rich fish oil exerts protective effects against experimental CM, reducing the mechanical and immunological events caused by the P. berghei ANKA infection.


Sujet(s)
Acides gras omega-3 , Paludisme cérébral , Enfant , Humains , Souris , Animaux , Enfant d'âge préscolaire , Huiles de poisson/pharmacologie , Acide docosahexaénoïque/pharmacologie , Acide docosahexaénoïque/usage thérapeutique , Paludisme cérébral/prévention et contrôle , Paludisme cérébral/traitement médicamenteux , Souris de lignée C57BL , Acides gras omega-3/usage thérapeutique , Anti-inflammatoires/pharmacologie , Anti-inflammatoires/usage thérapeutique
9.
J Microbiol Methods ; 217-218: 106873, 2024.
Article de Anglais | MEDLINE | ID: mdl-38128700

RÉSUMÉ

Silver nanoparticles incorporation into polymeric packaging aims to prevent microbiological contamination in food products, thus ensuring superior food safety and preservation. In this context, this study aimed to verify the antimicrobial efficacy of linear low-density polyethylene (LLDPE) films incorporated with silver nanoparticles (AgNPs) dispersed in silica (SiO2) and hydroxyapatite (HAP) carriers at different concentrations. AgNPs + carriers polymer films were characterized at 0.2, 0.4, and 0.6% concentrations using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), field emission gun-scanning electron microscope (FEG-SEM), thermogravimetric analyzer (TGA), differential scanning calorimetry (DSC), and migration in acidic and non-acidic simulants. Antimicrobial action was investigated on Gram-positive Staphylococcus aureus, Gram-negative Escherichia coli, and the Penicillium expansum and Fusarium solani fungi with antimicrobial activity by direct contact test and bacterial imaging by scanning electron microscopy. AgNPs addition to the LLDPE matrix did not interfere with the films' chemical and thermal properties and presented no significant migration to the external medium. For antimicrobial action, silver nanoparticles showed, in most concentrations, an inhibition percentage higher than 90% on all microorganisms studied, regardless of the carrier. However, a greater inhibitory action on S. aureus and between carriers was found, making hydroxyapatite more effective. The results indicated that nanostructured films with AgNPs + hydroxyapatite showed more promising antimicrobial action on microorganisms than AgNPs + silica, making hydroxyapatite with silver nanoparticle potentially useful in food packaging, improving safety and maintaining quality.


Sujet(s)
Anti-infectieux , Nanoparticules métalliques , Antibactériens/pharmacologie , Antibactériens/composition chimique , Argent/pharmacologie , Argent/composition chimique , Nanoparticules métalliques/composition chimique , Polyéthylène/composition chimique , Polyéthylène/pharmacologie , Silice/pharmacologie , Emballage alimentaire , Staphylococcus aureus , Durapatite/pharmacologie , Anti-infectieux/pharmacologie , Polymères/pharmacologie , Tests de sensibilité microbienne , Spectroscopie infrarouge à transformée de Fourier
10.
Int J Mol Sci ; 24(14)2023 Jul 12.
Article de Anglais | MEDLINE | ID: mdl-37511092

RÉSUMÉ

Newly emerging data suggest that several neutrophil defense mechanisms may play a role in both aggravating and protecting against malaria. These exciting findings suggest that the balance of these cells in the host body may have an impact on the pathogenesis of malaria. To fully understand the role of neutrophils in severe forms of malaria, such as cerebral malaria (CM), it is critical to gain a comprehensive understanding of their behavior and functions. This study investigated the dynamics of neutrophil and T cell responses in C57BL/6 and BALB/c mice infected with Plasmodium berghei ANKA, murine models of experimental cerebral malaria (ECM) and non-cerebral experimental malaria, respectively. The results demonstrated an increase in neutrophil percentage and neutrophil-T cell ratios in the spleen and blood before the development of clinical signs of ECM, which is a phenomenon not observed in the non-susceptible model of cerebral malaria. Furthermore, despite the development of distinct forms of malaria in the two strains of infected animals, parasitemia levels showed equivalent increases throughout the infection period evaluated. These findings suggest that the neutrophil percentage and neutrophil-T cell ratios may be valuable predictive tools for assessing the dynamics and composition of immune responses involved in the determinism of ECM development, thus contributing to the advancing of our understanding of its pathogenesis.


Sujet(s)
Paludisme cérébral , Animaux , Souris , Granulocytes neutrophiles/anatomopathologie , Souris de lignée C57BL , Plasmodium berghei , Lymphocytes T CD8+ , Modèles animaux de maladie humaine
11.
Microb Pathog ; 182: 106269, 2023 Sep.
Article de Anglais | MEDLINE | ID: mdl-37516212

RÉSUMÉ

Clostridium perfringens (types A and C) can cause several diseases by secreting alpha (CPA) and beta (CPB) exotoxins in the gastrointestinal tract. Although vaccination is the main measure of immunization against C. perfringens, available vaccines have limitations in terms of productivity and safety. Thus, recombinant vaccines are an important, more effective, practical, and safer strategy in the immunization of animals. In this study, we evaluated the immunization of sheep with recombinant Escherichia coli bacterins expressing CPA and CPB complete proteins (co-administered), the immunogenic nontoxic domains rCPA-C247-370 and rCPB-C143-311 co-administered or fused as a bivalent chimera (rCPBcAc). For this, in silico analysis was performed to design rCPBcAc, considering the stability of the mRNA (-278.80 kcal/mol), the degree of antigenicity (0.7557), the epitopes of the B cell ligand, and different physicochemical characteristics. All proteins were expressed in vitro. In vivo, animals vaccinated with the co-administered antigens rCPA + rCPB and rCPA-C+ rCPB-C (200 µg each) had mean CPA and CPB neutralizing antitoxin titers of 4, 10, 4.8, and 14.4 IU/mL, respectively, while those vaccinated with 200 µg of rCPBcAc chimera (approximately 100 µg of each antigen) had titers of <4 and 12 IU/mL of CPA and CPB antitoxins, respectively, 56 days after the administration of the first dose. In addition, the chimera was considered to be immunogenic for inducing antitoxin titers using the half dose. In this study, we presented a new recombinant antigen potentially applicable for vaccines against the CPA and CPB toxins for preventing diseases caused by Clostridium perfringens.


Sujet(s)
Antitoxines , Toxines bactériennes , Infections à Clostridium , Animaux , Ovis , Clostridium perfringens/métabolisme , Infections à Clostridium/prévention et contrôle , Infections à Clostridium/médecine vétérinaire , Vaccins antibactériens , Immunisation , Vaccination , Vaccins synthétiques , Anticorps antibactériens
12.
Sci Rep ; 13(1): 9546, 2023 06 12.
Article de Anglais | MEDLINE | ID: mdl-37308572

RÉSUMÉ

Blood coagulation is a vital process for humans and other species. Following an injury to a blood vessel, a cascade of molecular signals is transmitted, inhibiting and activating more than a dozen coagulation factors and resulting in the formation of a fibrin clot that ceases the bleeding. In this process, the Coagulation factor V (FV) is a master regulator, coordinating critical steps of this process. Mutations to this factor result in spontaneous bleeding episodes and prolonged hemorrhage after trauma or surgery. Although the role of FV is well characterized, it is unclear how single-point mutations affect its structure. In this study, to understand the effect of mutations, we created a detailed network map of this protein, where each node is a residue, and two residues are connected if they are in close proximity in the three-dimensional structure. Overall, we analyzed 63 point-mutations from patients and identified common patterns underlying FV deficient phenotypes. We used structural and evolutionary patterns as input to machine learning algorithms to anticipate the effects of mutations and anticipated FV-deficiency with fair accuracy. Together, our results demonstrate how clinical features, genetic data and in silico analysis are converging to enhance treatment and diagnosis of coagulation disorders.


Sujet(s)
Proaccélérine , Mutation ponctuelle , Humains , Mutation , Algorithmes , Évolution biologique
13.
PLoS One ; 18(6): e0286754, 2023.
Article de Anglais | MEDLINE | ID: mdl-37267411

RÉSUMÉ

Given the scarcity of studies relating fire to deforestation in the Atlantic Forest and great economic and ecological importances of this biome, this work aimed to investigate this relationship in the Atlantic Forest of the State of São Paulo, trying to answer whether deforestation is related to fire events in up to three years, if there are regions most affected by this relationship and what land use and land cover predominates after fire and deforestation in these areas. The study was carried out in Evergreen Forest and Semideciduous Seasonal, along the time series from 2000 to 2019 using the MapBiomas Project database to survey deforested and burned sites with moderate to high severity fires. Burning positively influenced deforestation in EGF in eight of 19 years studied (2001, 2004, 2005, 2007, 2008 and 2009, 2013 and 2015), while only for three years in the SSF. Burning followed by deforestation corresponded to only 3.2% of the total deforestation, located mainly in the eastern region of the state with the highest density in the EGF. Most of these areas have been converted to agriculture. This study provides the first indication that, generally, fire is not a driver of deforestation in the southeast Atlantic Forest.


Sujet(s)
Incendies , Feux de friches , Forêt pluviale , Conservation des ressources naturelles , Facteur de croissance épidermique , Brésil , Forêts
14.
Front Bioinform ; 3: 1152039, 2023.
Article de Anglais | MEDLINE | ID: mdl-37235045

RÉSUMÉ

Introduction: Blood coagulation is an essential process to cease bleeding in humans and other species. This mechanism is characterized by a molecular cascade of more than a dozen components activated after an injury to a blood vessel. In this process, the coagulation factor VIII (FVIII) is a master regulator, enhancing the activity of other components by thousands of times. In this sense, it is unsurprising that even single amino acid substitutions result in hemophilia A (HA)-a disease marked by uncontrolled bleeding and that leaves patients at permanent risk of hemorrhagic complications. Methods: Despite recent advances in the diagnosis and treatment of HA, the precise role of each residue of the FVIII protein remains unclear. In this study, we developed a graph-based machine learning framework that explores in detail the network formed by the residues of the FVIII protein, where each residue is a node, and two nodes are connected if they are in close proximity on the FVIII 3D structure. Results: Using this system, we identified the properties that lead to severe and mild forms of the disease. Finally, in an effort to advance the development of novel recombinant therapeutic FVIII proteins, we adapted our framework to predict the activity and expression of more than 300 in vitro alanine mutations, once more observing a close agreement between the in silico and the in vitro results. Discussion: Together, the results derived from this study demonstrate how graph-based classifiers can leverage the diagnostic and treatment of a rare disease.

15.
PLoS One ; 18(5): e0285988, 2023.
Article de Anglais | MEDLINE | ID: mdl-37256883

RÉSUMÉ

Abdominal wall defects in calves are commonly diagnosed and treated via laparotomy. This technique has witnessed several advancements in the management of these disorders. This study aimed to create a study model and evaluate the feasibility of video-assisted percutaneous correction of abdominal wall defects in bovine fetuses (corpses) compared with the conventional technique. Sixteen bovine fetuses from pregnant cows slaughtered in slaughterhouses were included in this study. The fetuses were categorized into the control group (CG, n = 8), which was subjected to umbilical abdominorrhaphy via laparotomy, and the video-surgical group (VG, n = 8), which received video-assisted percutaneous sutures with two lateral accesses on the right flank. An abdominal wall defect was created in the VG group to generate a study model, which was corrected using the laparoscopic technique. The procedures were performed in two steps. The first step consisted of creating an abdominal wall defect in the umbilical region by laparoscopic approach in an iatrogenic manner (Step 1: E1). The second stage consisted of conventional abdominorrhaphy of the umbilical region wall defect in the CG group and video-assisted percutaneous suturing of the edges of the iatrogenic abdominal wall defect in the VG group, until reversal of the laparoscopic accesses (Step 2: E2). Step 1 showed no statistically significant difference between the two groups. However, a significant statistical difference (p < 0.0001) was observed between the two groups in step 2. The surgical time of step 2 was longer in the CG group (33.10 ± 0.43 minutes) than that in the VG group (10.13 ± 0.68 minutes, p < 0.0001), and the total surgical time was also longer in the CG group (38.48 ± 0.35 minutes) than that in the VG group (15.86 ± 0.67 minutes). The proposed laparoscopic technique allowed the creation of a study model for video-assisted percutaneous suturing with two portals and reduced the surgical time compared with the conventional technique. However, this method needs to be studied further in live animals.


Sujet(s)
Paroi abdominale , Laparoscopie , Femelle , Grossesse , Bovins , Animaux , Paroi abdominale/chirurgie , Laparoscopie/méthodes , Muscles abdominaux , Foetus/chirurgie , Maladie iatrogène
16.
Mol Immunol ; 155: 69-78, 2023 03.
Article de Anglais | MEDLINE | ID: mdl-36731192

RÉSUMÉ

The present study was carried out to evaluate the intravaginal vaccine potential against bovine alphaherpesvirus type 5 (BoHV-5). Sixty three cows were divided into seven groups (n: 9) and inoculated intravaginally (VA) or intramuscularly (IM) with inactivated BoHV-5, associated with the recombinant B subunit of the heat-labile enterotoxin of E. coli (rLTB), 2-hydroxyethylcellulose (Drug Delivery System A - DDS-A) or Poloxamer 407 (Drug Delivery System B - DDS-B) as follows: G1 (DDS-A + BoHV-5 + rLTB), G2 (DDS-A + BoHV-5), G3 (DDS-B + BoHV-5 + rLTB), G4 (DDS-B + BoHV-5), G5 (BoHV-5 + rLTB), G6 (Negative control) e G7 (Positive control). The local and systemic humoral responses were measured by indirect ELISA (IgA and IgG) and serum neutralization tests, and the cellular response was measured by a quantitative direct ELISA (IL-2 and IFN-Gamma). The results showed the group inoculated by the IM route, G5, demonstrated the highest levels of IgG in the vaginal mucosa among the experimental groups (p < 0.05). In the groups tested with polymers (G1 and G3) in the vaginal mucosa, even higher levels of IgG were seen in comparison to the positive control (G7; p < 0.01). Higher levels of IgA were also noted in relation to the other groups (p < 0.05) on days 30, 60 and 90 post-inoculations. The groups G1 and G3 also provided higher titers of neutralizing antibodies (Log2) in relation to other treatments (p < 0.01) 90 days after inoculation. In the nasal mucosa, there was an increase in the levels of IgA and IgG with the use of vaccines from groups G1 and G3, in relation to the positive control, G7 (p < 0.05) at 60 and 90 days after the first inoculation. Moreover, neutralizing antibodies titers were detected at 60 and 90 days by serum neutralization. The inclusion of the evaluated polymers resulted in a superior response (p < 0.05) of immunoglobulins and IL-2 and IFN-Gamma in relation to the treatment using only rLTB (G5). This data demonstrates the capabilities of a vaccine with an intravaginal application in cattle to stimulate a local and systemic immune response.


Sujet(s)
Escherichia coli , Vaccins antiviraux , Animaux , Femelle , Bovins , Vaccins inactivés , Interleukine-2 , Anticorps neutralisants , Immunoglobuline G , Immunoglobuline A , Polymères , Anticorps antiviraux
17.
Lett Appl Microbiol ; 76(2)2023 Feb 16.
Article de Anglais | MEDLINE | ID: mdl-36763794

RÉSUMÉ

Some extraintestinal pathogenic Escherichia coli isolates (ExPEC), obtained from humans and chickens avian pathogenic E. coli (APEC), share similar virulence genes. Thus, products of avian origin can be a source of human infection. Moreover, these APEC isolates are resistant to antimicrobials and can spread in the environment through the chicken feces. Although the development of multidrug-resistant (MDR) microorganisms in poultry is on the rise, healthcare entities have raised concerns since MDRs can horizontally transfer resistance genes to other microorganisms and complicate the management of human infections by MDR APEC. The results of our study showed that of 80 investigated spiced chicken meat samples, 55% were contaminated with E. coli, of which 34% (15/44) contaminate with APEC. No diarrheagenic E. coli (DEC) pathotypes were found. Twenty-six isolates were MDR E. coli. Among the APEC isolates, 87% (13/15) produced extended-spectrum beta-lactamase (ESBL). The emergence of MDR/ESBL-producing APEC with zoonotic potential for humans is extremely worrying. Therefore, further studies are required to identify the prevalence of MDR/ESBL-producing APEC in the entire chicken production chain from creation, slaughter, processing, and butchery.


Sujet(s)
Infections à Escherichia coli , Maladies de la volaille , Animaux , Humains , Escherichia coli , Poulets , Infections à Escherichia coli/épidémiologie , Infections à Escherichia coli/médecine vétérinaire , Brésil/épidémiologie , Volaille , Hydrolases/génétique , Maladies de la volaille/épidémiologie , Antibactériens/pharmacologie , Phylogenèse , Viande
18.
Toxins (Basel) ; 15(1)2023 01 05.
Article de Anglais | MEDLINE | ID: mdl-36668862

RÉSUMÉ

In recent years, antimicrobial peptides isolated from amphibian toxins have gained attention as new multifunctional drugs interacting with different molecular targets. We aimed to rationally design a new peptide from temporin-PTa. Hp-MAP3 (NH2-LLKKVLALLKKVL-COOH), net charge (+4), hydrophobicity (0.69), the content of hydrophobic residues (69%), and hydrophobic moment (0.73). For the construction of the analog peptide, the physicochemical characteristics were reorganized into hydrophilic and hydrophobic residues with the addition of lysines and leucines. The minimum inhibitory concentration was 2.7 to 43 µM against the growth of Gram-negative and positive bacteria, and the potential for biofilm eradication was 173.2 µM. Within 20 min, the peptide Hp-MAP3 (10.8 µM) prompted 100% of the damage to E. coli cells. At 43.3 µM, eliminated 100% of S. aureus within 5 min. The effects against yeast species of the Candida genus ranged from 5.4 to 86.6 µM. Hp-MAP3 presents cytotoxic activity against tumor HeLa at a concentration of 21.6 µM with an IC50 of 10.4 µM. Furthermore, the peptide showed hemolytic activity against murine erythrocytes. Structural studies carried out by circular dichroism showed that Hp-MAP3, while in the presence of 50% trifluoroethanol or SDS, an α-helix secondary structure. Finally, Amphipathic Hp-MAP3 building an important model for the design of new multifunctional molecules.


Sujet(s)
Protéines d'amphibien , Peptides antimicrobiens cationiques , Animaux , Humains , Souris , Séquence d'acides aminés , Protéines d'amphibien/composition chimique , Protéines d'amphibien/pharmacologie , Antibactériens/pharmacologie , Peptides antimicrobiens cationiques/pharmacologie , Peptides antimicrobiens cationiques/composition chimique , Dichroïsme circulaire , Escherichia coli/effets des médicaments et des substances chimiques , Tests de sensibilité microbienne , Ranidae , Staphylococcus aureus/effets des médicaments et des substances chimiques
19.
Bioinform Adv ; 3(1): vbac098, 2023.
Article de Anglais | MEDLINE | ID: mdl-36698764

RÉSUMÉ

Summary: Blood coagulation is a vital process for humans and other species. Following an injury to a blood vessel, a cascade of molecular signals is transmitted, inhibiting and activating more than a dozen coagulation factors and resulting in the formation of a fibrin clot that ceases the bleeding. In this process, antithrombin (AT), encoded by the SERPINC1 gene is a key player regulating the clotting activity and ensuring that it stops at the right time. In this sense, mutations to this factor often result in thrombosis-the excessive coagulation that leads to the potentially fatal formation of blood clots that obstruct veins. Although this process is well known, it is still unclear why even single residue substitutions to AT lead to drastically different phenotypes. In this study, to understand the effect of mutations throughout the AT structure, we created a detailed network map of this protein, where each node is an amino acid, and two amino acids are connected if they are in close proximity in the three-dimensional structure. With this simple and intuitive representation and a machine-learning framework trained using genetic information from more than 130 patients, we found that different types of thrombosis have emerging patterns that are readily identifiable. Together, these results demonstrate how clinical features, genetic data and in silico analysis are converging to enhance the diagnosis and treatment of coagulation disorders. Supplementary information: Supplementary data are available at Bioinformatics Advances online.

20.
Biosci. j. (Online) ; 39: e39016, 2023. tab
Article de Anglais | LILACS | ID: biblio-1415904

RÉSUMÉ

Elephant grass is indicated for silage production but requires additives to increase dry matter content because it reduces the production of effluents, potentially improves the fermentation pattern, and preserves the nutrients of the silage. This study aimed to evaluate the effects of including macaúba cake in elephant grass ensilage on dry matter content, lactic acid bacteria population, lactic acid production, pH values, losses by gases and effluents, and dry matter recovery. The experimental design was completely randomized, in a 3x6 factorial scheme, with three levels of inclusion of macaúba cake (0, 10, and 20%) and six opening times (1, 5, 10, 20, 40, and 60 days after ensilage), with four repetitions. Macaúba cake was an effective moisture-absorbing additive, increasing dry matter content, lactic acid bacteria population, and lactic acid content and reducing the pH. The losses by effluents and gases decreased, and dry matter recovery increased with the addition of this biodiesel co-product. The 20% level of inclusion of macaúba cake in elephant grass ensilage allowed for better preserving the ensiled material.


Sujet(s)
Ensilage , Pennisetum , Aliment pour animaux
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