Artigos - Física e Biofísica - IBB

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  • ItemArtigo
    Leaf Angle as a Criterion for Optimizing Irrigation in Forest Nurseries: Impacts on Physiological Seedling Quality and Performance after Planting in Pots
    (2023-05-01) da Silva, Richardson Barbosa Gomes ; Simões, Danilo ; Wendling, Ivar ; do Prado, Débora Zanoni ; Sartori, Maria Márcia Pereira ; Bertholdi, Angelo Albano da Silva ; da Silva, Magali Ribeiro ; Universidade Estadual Paulista (UNESP) ; Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA)
    Seedling species with different architectures, e.g., mean leaf angles, are often subjected to the same irrigation management in forest nurseries, resulting in wasted water and fertilizer and reduced seedling quality. We aimed to evaluate whether irrigation volumes applied to tree seedling species with different leaf angles affect the physiological quality in forest nurseries and, consequently, performance after potting. We submitted nine seedling species with different mean leaf angles to four daily water regimes (8, 10, 12, and 14 mm). In the nursery, the following physiological attributes were considered to assess seedling quality: leaf water potential, daily transpiration rate, SPAD value, chlorophyll a and b, anthocyanins, carotenoids, and total nutrient content. After potting, we evaluated height and stem diameter over 120 days. Leaf angle can be used as a criterion for optimizing irrigation in forest nurseries, avoiding water and fertilizer wastage, and increasing physiological seedling quality. Leaf angle measurements combined with concurrent assessments of leaf traits are helpful in further understanding the effects of leaf angle variation and water regime on seedling quality. For positive leaf angles, an irrigation volume of 8 mm is sufficient to increase physiological seedling quality. Conversely, seedlings with negative leaf angles show the opposite response, requiring the largest irrigation volume (14 mm) to increase physiological seedling quality, except when the mean leaf area is small and concentrated in the upper half of the stem, which facilitates the access of irrigation water to the substrate and thus satisfies seedling water requirements. For all species, up to 120 days after planting in pots, the effect of the irrigation volume that provides greater growth and physiological quality at the end of the nursery phase is not overcome by other irrigation volumes applied.
  • ItemArtigo
    Performance and preference of Bemisia tabaci on tomato severe rugose virus infected tomato plants
    (2023-07-01) Bello, Vinicius Henrique ; Nogueira, Angélica Maria ; Sartori, Maria Márcia Pereira ; Pavan, Marcelo Agenor ; Rezende, Jorge Alberto Marques ; Ghanim, Murad ; Krause-Sakate, Renate ; Universidade Estadual Paulista (UNESP) ; Universidade de São Paulo (USP) ; Institute of Plant Protection
    Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) Middle East-Asia Minor 1 (MEAM1) and Mediterranean (MED) were reported as the sole vectors for tomato severe rugose virus (ToSRV), the prevalent begomovirus infecting tomato (Solanum lycopersicum L., Solanaceae) in Brazil. To improve our understanding on the interactions between B. tabaci and ToSRV, we studied the effects of the virus on the performance of MEAM1 and MED. Comparing adults’ performance on non-infected and ToSRV-infected tomato plants, the number of hatched eggs and emerged adults decreased for both MEAM1 and MED in infected tomato plants. However, the negative effect was more evident for MED, where the emergence of adults was reduced by 90% on ToSRV-infected tomatoes. In addition, the developmental time and percentage survival of MED on ToSRV-infected plants were severely affected compared to non-infected plants, while no differences were observed for MEAM1. Preference assays showed that non-viruliferous MEAM1 adults preferred to settle on non-infected plants in initial times (from 1 h to 6 h) but did not show preference between non-infected and infected plants in other evaluated times (from 12 h to 72 h). Viruliferous MEAM1 adults did not show a preference for either ToSRV-infected or non-infected plants. In contrast, MED non-viruliferous and viruliferous adults preferred to settle on non-infected plants compared to ToSRV-infected tomato plants. Our results indicate that ToSRV differently influences the performance and behavior of the whitefly species MEAM1 and MED, negatively interfering with the life parameters of MED.
  • ItemArtigo
    Renal resistive index in obese and non-obese cats
    (2022-01-01) de Souza, Fúlvia Bueno ; Gonçalves, Natália Volpi ; Bonatelli, Shayra Peruch ; Belotta, Alexandra Frey ; Geraldes, Silvano Salgueiro ; Mamprim, Maria Jaqueline ; Guimaraes-Okamoto, Priscylla Tatiana Chalfun ; Lourenço, Maria Lúcia Gomes ; Ramos, Paulo Roberto Rodrigues ; Rahal, Sheila Canevese ; Melchert, Alessandra ; Universidade Estadual Paulista (UNESP)
    This study aimed to compare renal function between obese and normal-weight healthy cats, using intrarenal resistive index (RI), serum symmetric dimethylarginine (SDMA), and serum creatinine, and to identify the variables that might influence intrarenal RI. Thirty crossbred client-owned cats met the inclusion criteria and were allocated into two groups: Control and Obese. Body weight, body mass index (BMI), body condition score (BCS), SAP, serum SDMA, urea, and creatinine were evaluated. B-mode and Doppler ultrasound of the kidneys were done. RI evaluation was in the interlobar artery. SDMA and intrarenal RI were compared between groups, also considering the gender of the cats. A correlation analysis between intrarenal RI with the other parameters was performed. SDMA was higher in the Obese group. Intrarenal RI was higher in females than males in the Obese group. Obese females presented higher RI and SDMA than Control females. A positive correlation was observed between RI, age, body weight, and BMI. Six obese cats (40%) showed increased RI. The increase in body weight, BCS, and BMI resulted in a simultaneous increase in RI and SDMA. The RI may assist in monitoring renal function, and may be associated with preclinical kidney changes in obese cats.
  • ItemResenha
    Intestinal Microbiota and miRNA in IBD: A Narrative Review about Discoveries and Perspectives for the Future
    (2023-04-01) Oliveira, Ellen Cristina Souza de ; Quaglio, Ana Elisa Valencise ; Magro, Daniéla Oliveira ; Di Stasi, Luiz Claudio ; Sassaki, Ligia Yukie ; Universidade Estadual Paulista (UNESP) ; Universidade Estadual de Campinas (UNICAMP)
    Inflammatory bowel disease (IBD) includes Crohn’s disease (CD) and ulcerative colitis (UC) and comprises a chronic gastrointestinal tract disorder characterized by hyperactive and dysregulated immune responses to environmental factors, including gut microbiota and dietary components. An imbalance of the intestinal microbiota may contribute to the development and/or worsening of the inflammatory process. MicroRNAs (miRNAs) have been associated with various physiological processes, such as cell development and proliferation, apoptosis, and cancer. In addition, they play an important role in inflammatory processes, acting in the regulation of pro- and anti-inflammatory pathways. Differences in the profiles of miRNAs may represent a useful tool in the diagnosis of UC and CD and as a prognostic marker in both diseases. The relationship between miRNAs and the intestinal microbiota is not completely elucidated, but recently this topic has gained prominence and has become the target of several studies that demonstrate the role of miRNAs in the modulation of the intestinal microbiota and induction of dysbiosis; the microbiota, in turn, can regulate the expression of miRNAs and, consequently, alter the intestinal homeostasis. Therefore, this review aims to describe the interaction between the intestinal microbiota and miRNAs in IBD, recent discoveries, and perspectives for the future.
  • ItemArtigo
    Longitudinal Study of Plasma Visfatin/Nicotinamide Phosphoribosyltransferase (NAMPT) Levels in Healthy Pregnant Women
    (2023-01-01) Nunes, Priscila R. ; Cavalli, Ricardo C. ; Belo, Vanessa A. ; Sandrim, Valeria C. ; Luizon, Marcelo R. ; Universidade Estadual Paulista (UNESP) ; Universidade de São Paulo (USP) ; Federal University of Ouro Preto (UFOP) ; Universidade Federal de Minas Gerais (UFMG)
    Visfatin/nicotinamide phosphorybosil transferase (NAMPT) is a novel adipocytokine with potential roles in the pathophysiology of metabolic disorders, including gestational disorders. However, there is no clear interpretation regarding the circulating visfatin levels in a healthy pregnancy. Therefore, we conducted the first longitudinal study of plasma visfatin levels that followed up healthy pregnant women until the third trimester, including the postpartum period (PPP). The study recruited healthy women with singleton pregnancy who were not using any drug (including tobacco and alcohol). We have excluded pregnant women who did not attend all scheduled exams and developed gestational diabetes or hypertension, obesity, preeclampsia, or any infections during pregnancy. Nine women were considered eligible and examined during all three trimesters of pregnancy and between 8 and 12 weeks postpartum (PPP). Visfatin/NAMPT concentrations were measured in EDTA-plasma by ELISA. The mean age of pregnant women included was 22±5 years (54% primiparous), and the mean of gestational age at delivery was 40±1.2 weeks. Mean systolic and diastolic blood pressures were 90 and 70 mmHg, respectively. Mean values (± standard error mean) of visfatin concentrations (μg/L) during trimesters were 11.38±1.45 (first, 11–14 weeks), 9.18±1.82 (second, 20–24 weeks), 18.67±2.65 (third, 34–36 weeks), and 10.12±1.49 in the PPP. The value of the third trimester was significantly higher than the second trimester, and significantly reduced in the PPP (p<0.05, ANOVA with Bonferroni’s multiple comparison tests). Visfatin/NAMPT levels are significantly lower in the PPP, suggesting that factors stimulating its production would be limited to pregnancy, thereby contributing to its potential application as a biomarker in pregnancy complications.
  • ItemArtigo
    6-Nitrodopamine potentiates contractions of rat isolated vas deferens induced by noradrenaline, adrenaline, dopamine and electric field stimulation
    (2023-01-01) Britto-Júnior, José ; Lima, Antonio Tiago ; Campos, Rafael ; Gião, Alexandre Asturiano ; Mendes, Gustavo Duarte ; Ferreira-Novaes Silva, Luiza P. ; Fregonesi, Adriano ; Pupo, André Sampaio ; Antunes, Edson ; De Nucci, Gilberto ; Universidade Estadual de Campinas (UNICAMP) ; São Leopoldo Mandic (SLMANDIC) ; Universidade Estadual Paulista (UNESP) ; Universidade de São Paulo (USP)
    6-Nitrodopamine (6-ND) is a novel endogenous catecholamine that is released from the rat isolated vas deferens, and has been characterized as a major modulator of the contractility of rat isolated epididymal vas deferens (RIEVD). Drugs such as tricyclic antidepressants, α1 and β1β2 adrenoceptor blockers, act as selective antagonists of the 6-ND receptor in the RIEVD. In the rat isolated atria, 6-ND has a potent positive chronotropic action and causes remarkable potentiation of the positive chronotropic effects induced by dopamine, noradrenaline, and adrenaline. Here, whether 6-ND interacts with the classical catecholamines in the rat isolated vas deferens was investigated. Incubation with 6-ND (0.1 and 1 nM; 30min) caused no contractions in the RIEVD but provoked significant leftward shifts in the concentration-response curves to noradrenaline, adrenaline, and dopamine. Pre-incubation of the RIEVD with 6-ND (1 nM), potentiated the contractions induced by electric-field stimulation (EFS), whereas pre-incubation with 1 nM of dopamine, noradrenaline or adrenaline, did not affect EFS-induced contractions. In tetrodotoxin (1 μM) pre-treated (30 min) RIEVD, pre-incubation with 6-ND (0.1 nM) did not cause leftward shifts in the concentration-dependent contractions induced by noradrenaline, adrenaline, or dopamine. Pre-incubation of the RIEVD with the α2A-adrenoceptor antagonist idazoxan (30 min, 10 nM) did not affect dopamine, noradrenaline, adrenaline, and EFS-induced contractions. However, when idazoxan (10 nM) and 6-ND (0.1 nM) were simultaneously pre-incubated (30 min), a significant potentiation of the EFS-induced contractions of the RIEVD was observed. 6-nitrodopamine causes remarkable potentiation of dopamine, noradrenaline, and adrenaline contractions on the RIEVD, due to activation of adrenergic terminals, possibly via pre-synaptic adrenoceptors.
  • ItemArtigo
    Structural and functional insights of the catalytic GH5 and Calx-β domains from the metagenome-derived endoglucanase CelE2
    (2023-04-01) Pimentel, Agnes C. ; Liberato, Marcelo V. ; Franco Cairo, João Paulo L. ; Tomazetto, Geizecler ; Gandin, César A. ; de Oliveira Neto, Mario ; Alvarez, Thabata M. ; Squina, Fabio M. ; Universidade Estadual de Campinas (UNICAMP) ; Cidade Universitária ; Cidade Industrial ; Universidade Estadual Paulista (UNESP)
    Cellulose is the most abundant natural polymer on Earth, representing an attractive feedstock for bioproducts and biofuel production. Cellulases promote the depolymerization of cellulose, generating short oligosaccharides and glucose, which are useful in biotechnological applications. Among the classical cellulases, those from glycoside hydrolase family 5 (GH5) are one of the most abundant in Nature, displaying several modular architectures with other accessory domains attached to its catalytic core, such as carbohydrate-binding modules (CBMs), Ig-like, FN3-like, and Calx-β domains, which can influence the enzyme activity. The metagenome-derived endoglucanase CelE2 has in its modular architecture an N-terminal domain belonging to the GH5 family and a C-terminal domain with a high identity to the Calx-β domain. In this study, the GH5 and the Calx-β domains were subcloned and heterologously expressed in E. coli, to evaluate the structural and functional properties of the individualized domains of CelE2. Thermostability analysis by circular dichroism (CD) revealed a decrease in the denaturation temperature values around 4.6 °C for the catalytic domain (CelE21–381) compared to CelE2 full-length. The CD analyses revealed that the Calx-β domain (CelE2382–477) was unfolded, suggesting that this domain requires to be attached to the catalytic core to become structurally stable. The three-dimensional structure of the catalytic domain CelE21–381 was determined at 2.1 Å resolution, showing a typical (α/β)8-barrel fold and a narrow active site compared to other cellulases from the same family. The biochemical characterization showed that the deletion of the Calx-β domain increased more than 3-fold the activity of the catalytic domain CelE21–381 towards the insoluble substrate Avicel. The main functional properties of CelE2, such as substrate specificity, optimal pH and temperature, thermal stability, and activation by CaCl2, were not altered after the deletion of the accessory domain. Furthermore, the Small Angle X-ray Scattering (SAXS) analyses showed that the addition of CaCl2 was beneficial CelE21–381 protein solvency. This work contributed to fundamental concepts about the structure and function of cellulases, which are useful in applications involving lignocellulosic materials degradation into food and feedstuffs and biofuel production.
  • ItemArtigo
    Low dose of cyclosporine A disrupts sperm parameters and testosterone levels reversibly in mice
    (2023-02-01) Siervo, Gláucia Eloisa Munhoz de Lion ; Mariani, Noemia Aparecida Partelli ; Silva, Alan Andrew S. ; Punhagui-Umbelino, Ana Paula Franco ; Costa, Ivana Regina da ; Andrade, Alexandre Dorth de ; Silva, Erick J.R. ; Fernandes, Glaura Scantamburlo Alves ; Universidade Estadual de Londrina (UEL) ; Universidade Estadual Paulista (UNESP)
    The prevalence of autoimmune diseases has increased worldwide, including in men of reproductive age. Cyclosporine A (CsA) is an immunosuppressive drug commonly used for long periods in the prophylaxis and treatment of autoimmune dysfunction and transplant rejection. Owing to CsA toxicity, most clinical settings use lower CsA doses. Therefore, we evaluated whether a low dose (10 mg/kg) of CsA affects sperm parameters (daily sperm production, motility, morphology, mitochondrial activity, and acrosomal integrity), plasma testosterone levels, and fertility after short-term (10 days) and long-term (50 days) treatments in mice. Short-term CsA treatment partially affected sperm parameters and fertility, as shown by the reduction in sperm hyperactivation and gestational rate 10 days after the interruption of short-term CsA treatment. Long-term CsA treatment impairs sperm count, hyperactivated motility, and acrosomal integrity. This treatment regimen further decreased plasma testosterone concentrations but did not affect reproductive outcomes in mating trials. These outcomes were reversed 50 days after the interruption of long-term CsA treatment. We conclude that a low CsA dose differentially impairs sperm parameters and testicular steroidogenesis in a time-dependent and mostly reversible manner but does not affect male fertility.
  • ItemArtigo
    New multienzymatic complex formed between human cathepsin D and snake venom phospholipase A2
    (2022-01-01) Moraes, Jeane do Nascimento ; Francisco, Aleff Ferreira ; Dill, Leandro Moreira ; Diniz, Rafaela Souza ; de Oliveira, Claudia Siqueira ; da Silva, Tainara Maiane Rodrigues ; Caldeira, Cleópatra Alves da Silva ; Corrêa, Edailson de Alcântara ; Coutinho-Neto, Antônio ; Zanchi, Fernando Berton ; Fontes, Marcos Roberto de Mattos ; Soares, Andreimar Martins ; Calderon, Leonardo de Azevedo ; Oswaldo Cruz Foundation (FIOCRUZ) ; Federal University of Rondônia (UNIR) ; Universidade Estadual Paulista (UNESP) ; INCT-EPIAMO ; Smart Active Ingredients Lab (SAIL) ; University of Buenos Aires (UBA) ; Science and Technology of Rondonia (IFRO) ; São Lucas University Center (UniSL) ; Aparicio Carvalho University Center (FIMCA)
    Background: Cathepsin D (CatD) is a lysosomal proteolytic enzyme expressed in almost all tissues and organs. This protease is a multifunctional enzyme responsible for essential biological processes such as cell cycle regulation, differentiation, migration, tissue remodeling, neuronal growth, ovulation, and apoptosis. The overexpression and hypersecretion of CatD have been correlated with cancer aggressiveness and tumor progression, stimulating cancer cell proliferation, fibroblast growth, and angiogenesis. In addition, some studies report its participation in neurodegenerative diseases and inflammatory processes. In this regard, the search for new inhibitors from natural products could be an alternative against the harmful effects of this enzyme. Methods: An investigation was carried out to analyze CatD interaction with snake venom toxins in an attempt to find inhibitory molecules. Interestingly, human CatD shows the ability to bind strongly to snake venom phospholipases A2 (svPLA2), forming a stable muti-enzymatic complex that maintains the catalytic activity of both CatD and PLA2. In addition, this complex remains active even under exposure to the specific inhibitor pepstatin A. Furthermore, the complex formation between CatD and svPLA2 was evidenced by surface plasmon resonance (SPR), two-dimensional electrophoresis, enzymatic assays, and extensive molecular docking and dynamics techniques. Conclusion: The present study suggests the versatility of human CatD and svPLA2, showing that these enzymes can form a fully functional new enzymatic complex.
  • ItemArtigo
    Circulating levels of tissue inhibitor of metalloproteinase 3, a protein with inhibitory effects on angiogenesis, are increased in pre-eclampsia
    (2023-05-01) Palei, Ana C. ; Cruz, Juliana de O. ; Chaguri, João Leandro ; Peraçoli, José Carlos ; Romão-Veiga, Mariana ; Ribeiro-Vasques, Vanessa R. ; Cavalli, Ricardo C. ; Nunes, Priscila R. ; Luizon, Marcelo R. ; Sandrim, Valéria C. ; University of Mississippi Medical Center ; Universidade Federal de Minas Gerais (UFMG) ; Universidade Estadual Paulista (UNESP) ; Universidade de São Paulo (USP)
    Objective: To assess and compare circulating tissue inhibitor of metalloproteinase 3 (TIMP-3) concentrations between women with pre-eclampsia and healthy pregnant women. We also aimed to determine the relationships between circulating TIMP-3 and matrix metalloproteinase 2 (MMP-2), MMP-9, TIMP-1, and TIMP-2 concentrations in pre-eclampsia. Methods: A primary case–control study included patients with pre-eclampsia (n = 219) and gestational hypertension (n = 118), healthy pregnant women (n = 214), and non-pregnant women (n = 66), and a replication case–control study included patients with pre-eclampsia (n = 177) and healthy pregnant women (n = 124), all from southeastern Brazil. Plasma TIMP-3, MMP-2, MMP-9, TIMP-1, and TIMP-2 concentrations were assessed using commercially available enzyme-linked immunosorbent assay kits, and the relationships between them were analyzed using Spearman's correlation. Results: In our primary study, patients with pre-eclampsia and gestational hypertension exhibited increased TIMP-3 concentrations compared with healthy pregnant women (both P < 0.0001) and non-pregnant women (both P < 0.001). These findings were confirmed in the replication study, showing elevated TIMP-3 concentrations in women with pre-eclampsia versus healthy pregnant women (P < 0.001). We found no difference in TIMP-3 concentrations between early-onset and late-onset pre-eclampsia. Moreover, TIMP-3 concentrations were significantly correlated with plasma concentrations of TIMP-1 (r = 0.2333; P = 0.0086) and MMP-2 (r = 0.2159; P = 0.0156) in pre-eclampsia. Conclusions: Circulating TIMP-3 concentration is increased in women with pre-eclampsia compared with healthy pregnant women, and it is positively correlated with plasma MMP-2 and TIMP-1 concentrations in pre-eclampsia.
  • ItemArtigo
    FK506 impairs neutrophil migration that results in increased polymicrobial sepsis susceptibility
    (2023-02-01) Borges, Vanessa de Fátima ; Galant, Leticia Selinger ; Kanashiro, Alexandre ; Castanheira, Fernanda Vargas e Silva ; Monteiro, Valter Vinícius Silva ; Duarte, Diego Ângelo ; Rodrigues, Filipe Camargo ; Silva, Camila Meirelles de Souza ; Schneider, Ayda Henriques ; Cebinelli, Guilherme Cesar Martelossi ; de Lima, Mikhael Haruo Fernandes ; Viola, João Paulo de Biaso ; Cunha, Thiago Mattar ; da Costa Neto, Claudio Miguel ; Alves-Filho, José Carlos Farias ; Pupo, André Sampaio ; Cunha, Fernando de Queiroz ; Universidade de São Paulo (USP) ; National Cancer Institute (INCA) ; Universidade Estadual Paulista (UNESP)
    Objective: This study aimed to investigate the effects of FK506 on experimental sepsis immunopathology. It investigated the effect of FK506 on leukocyte recruitment to the site of infection, systemic cytokine production, and organ injury in mice with sepsis. Methods: Using a murine cecal ligation and puncture (CLP) peritonitis model, the experiments were performed with wild-type (WT) mice and mice deficient in the gene Nfat1 (Nfat1−/−) in the C57BL/6 background. Animals were treated with 2.0 mg/kg of FK506, subcutaneously, 1 h before the sepsis model, twice a day (12 h/12 h). The number of bacteria colony forming units (CFU) was manually counted. The number of neutrophils in the lungs was estimated by the myeloperoxidase (MPO) assay. The expression of CXCR2 in neutrophils was determined using flow cytometry analysis. The expression of inflammatory cytokines in macrophage was determined using ELISA. The direct effect of FK506 on CXCR2 internalization was evaluated using HEK-293T cells after CXCL2 stimulation by the BRET method. Results: FK506 treatment potentiated the failure of neutrophil migration into the peritoneal cavity, resulting in bacteremia and an exacerbated systemic inflammatory response, which led to higher organ damage and mortality rates. Failed neutrophil migration was associated with elevated CXCL2 chemokine plasma levels and lower expression of the CXCR2 receptor on circulating neutrophils compared with non-treated CLP-induced septic mice. FK506 did not directly affect CXCL2-induced CXCR2 internalization by transfected HEK-293 cells or mice neutrophils, despite increasing CXCL2 release by LPS-treated macrophages. Finally, the CLP-induced response of Nfat1−/− mice was similar to those observed in the Nfat1+/+ genotype, suggesting that the FK506 effect is not dependent on the NFAT1 pathway. Conclusion: Our data indicate that the increased susceptibility to infection of FK506-treated mice is associated with failed neutrophil migration due to the reduced membrane availability of CXCR2 receptors in response to exacerbated levels of circulating CXCL2.
  • ItemArtigo
    Phospholipase A(2) Inhibitors from Snake Blood (sbPLIs)
    (Springer, 2017-01-01) Fortes-Dias, Consuelo L. ; Campos, Patricia Cota ; Fernandes, Carlos Alexandre H. ; Fontes, Marcos Roberto M. ; Inagaki, H. ; Vogel, C. W. ; Mukherjee, A. K. ; Rahmy, T. R. ; Gopalakrishnakone, P. ; Fundacao Ezequiel Dias ; Universidade Estadual Paulista (UNESP)
    Several snake species have been naturally provided with protein inhibitors with the primary aim of self-protection against the eventual presence of venom toxins in their circulating blood. Phospholipase A(2) inhibitors are among the most studied molecules in that group. Such molecules have been identified in venomous and nonvenomous snake species and are generally known as sbPLIs (which stand for snake blood phospholipase A(2) inhibitors). Based on the presence of known domains of mammalian proteins, sbPLIs may belong to any of three structural classes (alpha, beta, or gamma). All the domains are involved in protein-protein interactions. The sbaPLIs present a characteristic C-type lectin-like domain (CTLD) highly similar to the carbohydrate recognition domain (CRD) of Ca2+-dependent lectins, which includes mannose-binding and lung surfactants A and D (SP-A and SP-D) proteins. Beta-type inhibitors (sb beta PLIs) are characterized by the presence of nine tandem leucine-rich repeats (LRRs), whereas sb.PLIs share the characteristic three-finger motifs of the Ly-6 family, CD59 and the urokinase-type plasminogen activator (u-PAR). Despite of no crystallographic data of sbPLIs, several computational and biophysical techniques have been applied, in an effort to provide structural data for structure-function relationships between these inhibitors and svPLAs. This chapter will be devoted to a brief but not extensive review of general aspects, quaternary structures, molecular mechanisms, and applications of sbPLIs.
  • ItemArtigo
    Potential Applications of Nanoparticles for Hyperthermia
    (Springer, 2015-01-01) Quini, Caio Cesar ; Krishnan, Sunil ; Asea, AAA ; Almasoud, N. N. ; Krishnan, S. ; Kaur, P. ; Univ Texas MD Anderson Canc Ctr ; Universidade Estadual Paulista (UNESP)
    There is converging evidence that clinical mild temperature hyperthermia sensitizes tumors to conventional therapies as chemotherapy and radiation therapy. Coupled with an increasing understanding of the biological basis of this synergy there has been a parallel increase in the ability to achieve, maintain, measure and monitor temperature and its physiological and physical consequences. A new entrant in the arena of hyperthermia generation is nanotechnology which capitalizes on locally injected or systemically administered nanoparticles that home to tumors and are activated by extrinsic energy sources to generate heat. This chapter highlights the unique opportunities and challenges with implementing hyperthermia mediated by a variety of engineered nanoparticles for cancer therapy.
  • ItemResenha
    Evaluation of resistance of Bt and non-Bt maize genotypes to Dalbulus maidis (Hemiptera: Cicadellidae) and associated mollicutes
    (2022-01-01) Faria, Rodrigo Donizeti ; Fanela, Thiago Luis Martins ; Sartori, Maria Márcia Pereira ; Lopes, João Roberto Spotti ; Lourenção, André Luiz ; Baldin, Edson Luiz Lopes ; Universidade Estadual Paulista (UNESP) ; Universidade de São Paulo (USP)
    Corn is one of the main cereals grown in Brazil. However, attack of pest arthropods may compromise significantly crop yield. The corn leafhopper Dalbulus maidis (DeLong & Wolcott) (Hemiptera: Cicadellidae) is a vector of maize stunting pathogens, such as the mollicutes Spiroplasma kunkelli (corn stunt spiroplasma) and Candidatus Phytoplasma asteris (maize bushy stunt phytoplama). Resistant maize genotypes to the leafhopper and the associated mollicutes is a valuable strategy for reducing the dependence on synthetic insecticides for disease control. This study evaluated leafhopper infestation and incidence of mollicutes in 30 genotypes of Bt and non-Bt corn under field conditions in order to characterize possible resistance to both organisms. Two experiments were conducted in a randomized block design during the fall (2018) and the summer (2018/2019) seasons. The assessments of infestation by leafhopper nymphs and adults on plants were carried out every two weeks from the phenological stages V4 to V5 until VT-R1 for both seasons. The incidence of mollicutes in the genotypes was evaluated during the summer season by PCR analysis. There was no significant difference regarding the infestation by leafhopper adults on the genotypes studied in both seasons. However, genotypes 90XB06 Bt, SCS 156 Colorado, IAC 8046 and DKB 310 VTPRO3 were not infected by phytoplasma and spiroplasma, indicating their potential for resistance to these maize stunting pathogens. Our results can assist breeding programs focusing on maize genotypes resistant to the mollicutes transmitted by D. maidis.
  • ItemArtigo
    ARG2 single-nucleotide polymorphism rs3742879 affects plasma arginase 2 levels, nitric oxide formation and antihypertensive therapy response in preeclampsia
    (2022-08-01) Luizon, Marcelo R. ; Pinto-Souza, Caroline C. ; Coeli-Lacchini, Fernanda ; Lacchini, Riccardo ; Cavalli, Ricardo C. ; Sandrim, Valeria C. ; Universidade Federal de Minas Gerais (UFMG) ; Universidade Estadual Paulista (UNESP) ; Universidade de São Paulo (USP)
    Aim: This work examined whether ARG1 (rs2781659, rs2781667, rs2246012 and rs17599586) and ARG2 (rs3742879 and rs10483801) single-nucleotide polymorphisms (SNPs) are associated with antihypertensive therapy responsiveness in preeclampsia (PE) and their effects on arginase isoforms and nitrite concentrations in responsive and nonresponsive patients. Methods: SNP genotypes were determined by TaqMan assays. Plasma arginase levels were measured by ELISA and nitrite concentrations were measured using an ozone-based chemiluminescence assay. Results: The G allele for ARG2 rs3742879 (A>G) was less frequent in nonresponsive compared with responsive patients (15.5% vs 24.7%, respectively) and the G carriers of the nonresponsive subgroup had lower arginase 2 (9.2 ± 7.5 ng/ml vs 19.1 ± 17.3 ng/ml) and higher nitrite concentrations (110.2 ± 52.8 nM vs 78.5 ± 37.9 nM) than carriers of the AA genotype (all p < 0.05). Conclusion: ARG2 SNP rs3742879 is associated with diminished arginase 2 levels and increased nitric oxide formation in nonresponsive PE patients.
  • ItemArtigo
    Anti-Metalloprotease P-I Single-Domain Antibodies: Tools for Next-Generation Snakebite Antivenoms
    (2022-01-01) Silva, Marcela C. S. ; Pereira, Soraya S. ; Gouveia, Marilia P. ; Luiz, Marcos B. ; Sousa, Rosa M. O. ; Kayano, Anderson M. ; Francisco, Aleff F. ; Prado, Nidiane D. R. ; Dill, Leandro S. M. ; Fontes, Marcos R. M. ; Zanchi, Fernando B. ; Stabeli, Rodrigo G. ; Soares, Andreimar M. ; Zuliani, Juliana P. ; Fernandes, Carla F. C. ; Rondônia ; Centro de Pesquisa em Medicina Tropical ; Universidade Estadual Paulista (UNESP) ; Universidade de São Paulo (USP) ; INCT-EpiAmO ; UNIR ; Eusébio
    In order to address the global antivenom crisis, novel antivenoms need to present high therapeutic efficacy, broad neutralization ability against systemic and local damage, sufficient safety, and cost-effectiveness. Due to biological characteristics of camelid single-domain antibodies (VHH) such as high affinity, their ability to penetrate dense tissues, and facility for genetic manipulation, their application in antivenoms has expanded considerably. VHHs that are active against the metalloprotease BjussuMP-II from the snake Bothrops jararacussu were selected. After isolation of BjussuMP-II, a camelid was immunized with the purified toxin in order to construct the recombinant phage library. Following a round of biopanning, 52% of the selected clones were able to recognize BjussuMP-II in an ELISA assay. After sequencing, seven sequence profiles were identified. One selected clone (VHH61) showed cross-reactivity to B. brazili venom, but did not recognize the Crotalus and Lachesis genera, indicating specificity for the Bothrops genus. Through in vitro tests, the capacity to neutralize the toxicity triggered by BjussuMP-II was observed. Circular dichroism spectroscopy indicated a robust secondary structure for VHH61, and the calculated melting temperature (TM) for the clone was 56.4°C. In silico analysis, through molecular docking of anti-BjussuMP-II VHHs with metalloprotease, revealed their potential interaction with amino acids present in regions critical for the toxin's conformation and stability. The findings suggest that anti-BjussuMP-II VHHs may be beneficial in the development of next-generation antivenoms.
  • ItemEditorial
    Editorial: Integrative Structural Biology of Proteins and Macromolecular Assemblies: Bridging Experiments and Simulations
    (2022-06-27) Batista, Paulo Ricardo ; Oliveira Neto, Mario ; Perahia, David ; Fundação Oswaldo Cruz ; Universidade Estadual Paulista (UNESP) ; Centre National de la Recherche Scientifique
  • ItemTrabalho apresentado em evento
    Characterization of Electroencephalogram Obtained During the Resolution of Mathematical Operations Using Recurrence Quantification Analysis
    (2022-01-01) Mendes, A. P. ; Jarola, G. M. ; Oliveira, L. M.A. ; Gerhardt, G. J.L. ; Rybarczyk-Filho, J. L. ; Santos, L. dos ; Universidade Brasil ; Universidade Estadual Paulista (UNESP) ; Universidade de Caxias do Sul
    This work aims to apply recurrence quantification analysis to characterize electroencephalogram signals, in resting and active state situations involving mathematical operation resolution. The best values of the incorporation parameters (delay time, embedding dimension, and threshold) are investigated to obtain the best ranking results. The measures of the recurrence quantification analysis used are recurrence rate, determinism, overage length of diagonal structures, Shannon entropy, laminarity, and maximum length of vertical structures. To compare between resting and active state, the Mann-Whitney test was performed. The results demonstrate that the resting state is predominant in the alpha and theta experiments. Statistical differences were observed in the comparisons between resting and active state for alpha and theta experiments, active state alpha and active state theta experiments and resting and active state for theta experiments.
  • ItemArtigo
    Defense response-like reaction associated with an anomaly in Eucalyptus grandis
    (2022-01-01) Fuchs, Maria C. P. ; Rossini, Bruno C. ; Acencio, Marcio L. ; Lemke, Ney ; González, Esteban R. ; Moricca, Salvatore ; Panzavolta, Tiziana ; Furtado, Edson L. ; Oda, Shinitiro ; Marino, Celso L. ; Universidade Estadual Paulista (UNESP) ; University of Luxembourg ; Empresa Suzano Papel e Celulose SA ; University of Florence
    Key message: Based on transcriptome and qPCR analysis, a phenotypic abnormality resulting from a Eucalyptus crossing is associated with overexpression of metabolic pathways related to defense responses against biotic and abiotic stress. Abstract: Genetic recombination by outcrossing, a strategy used in improvement programs, can present a low frequency of individuals within progeny with morphological and physiological abnormalities. An abnormality was identified in progeny from a controlled cross of Eucalyptus grandis. Applying RNA-Seq technology to leaf, stem, and root tissue of normal and abnormal seedlings grown under the same greenhouse conditions, we examined global gene expression changes and compared the transcriptional profiles of the two contrasting phenotypes. We also conducted functional enrichment and metabolic pathway analyses. Among the identified differentially expressed genes, most were upregulated in leaf and stem tissues of abnormal plants, with gene ontology (GO) terms associated with 'response to stress', 'response to stimulus', and 'immune system process' categories. Further, in differential gene expression and functional enrichment analyses, we observed overexpression of metabolic pathways related to defense response processes in abnormal plants. Our results suggest that the anomaly is associated with changes in the defense response to biotic and abiotic stresses. As all progeny were grown in a controlled environment and there was no evidence of pathogenic attacks, the defense response in abnormal plants may be due to an autoimmune mechanism caused by genetic incompatibility.
  • ItemArtigo
    Physiological and biochemical responses of osmo-primed parsley seeds subjected to saline stress
    (2022-01-01) Manjavachi, Matheus Kainan de Paula ; Silva, Tiago Alexandre ; Guimarães, Cristiane Carvalho ; Sartori, Maria Márcia Pereira ; da Silva, Edvaldo Aparecido Amaral ; Universidade Estadual Paulista (UNESP)
    Water and salt stress conditions affect germination and seedling emergence. It is known that physiological priming can not only trigger different mechanisms to increase the speed and uniformity of germination, but also influence the antioxidant defence system of the seeds, especially in adverse conditions. In this context, the objective of this work was to evaluate the physiological seed quality and the activity of antioxidant enzymes in seeds of Petroselinum crispum induced to tolerate saline stress through osmo-priming. Seeds were placed in polyethylene glycol solutions with three osmotic potentials (-0.5,-1.0 or-1.5 MPa) for 2, 4 or 6 days. Subsequently, they were placed on substrates moistened with sodium chloride solution (NaCl), in concentrations that generated osmotic potentials of-0.2,-0.4,-0.6,-0.8 or-1.0 MPa, to germinate. The germination percentage, germination speed index, seedling length, fresh weight, dry weight and activity of the antioxidant enzymes superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) were evaluated. Germination and germination speed index decreased linearly with the increase in NaCl concentrations, indicating the species sensitivity. As for length, fresh weight and dry weight of seedlings, this effect was more expressive from the potential of-0.4 MPa. The vigour and activity of SOD, POD, and CAT enzymes were reduced in unprimed seeds, emphasising the effectiveness of the technique. The induction of tolerance to saline stress can be related to the activity of the antioxidant system observed in seeds.