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1.
Life (Basel) ; 13(9)2023 Aug 30.
Article in English | MEDLINE | ID: mdl-37763242

ABSTRACT

BACKGROUND: Radiotherapy can affect healthy cells, resulting in side effects. This study aimed to assess the impact of radiotherapy on soft tissue in surgical wounds in rats. METHODS: The animals were divided into four groups: control (S) group without irradiation, immediate irradiation (S-IIr) group receiving irradiation right after surgery, late irradiation (S-LIr) group receiving irradiation four weeks after surgery, and early irradiation (Ir-S) group receiving irradiation before surgery. The irradiated groups underwent two fractional stages of 15 Gy. Muscle contractibility (EMG) was evaluated at two different time points, and after 2 and 7 weeks, the animals were euthanized for histological analysis of the muscles and skin. RESULTS: There was no significant difference between the EMG1 and EMG2 values of the S and S-LIr groups, but both S-IIr and Ir-S groups exhibited a statistically significant difference. The S group demonstrated a larger diameter of muscle fiber compared to other groups, showing a significant difference. In terms of skin analysis, the S-IIr group had the least inflammatory infiltrate and the highest amount of red fibers, differing significantly from the other groups. CONCLUSIONS: Regardless of the duration, radiotherapy was found to have effects on the surrounding soft tissues, as concluded by this study.

2.
An Acad Bras Cienc ; 94(4): e20201133, 2022.
Article in English | MEDLINE | ID: mdl-36449895

ABSTRACT

Objective was evaluated the therapeutic effect of Juglans regia (J) and Zingiber officinale (Z) extracts, alone or associated (Z75% + J25%, Z50% + J50% and Z25% + J75%) applied on planktonic cultures and biofilms of Propionibacterium acnes, Staphylococcus epidermidis and Staphylococcus aureus, as well as analyzing the cytotoxic effects of plant extracts on mouse macrophages (Raw 264-7). Broth microdilution assay was performed (M7-A6 - CLSI). Anti-biofilm activities and cytotoxicity on Raw 264-7 were studied using MTT assay and scanning electron microscopy. ANOVA with post-hoc Tukey HSD applied for parametric data and Kruskal-Wallis with Conover-Iman test, for non-parametric (p<0.05). On P. acnes biofilm, Z50% + J50% reduced 46.9% in 5 min and Z25% + J75% reduced 74.1% in 24hs. On S. aureus, Z75% + J25% reduced 23.1% in 5 min Z25% +J75% reduced 79.4% in 24hs. On S. epidermidis, Z75% + J25% reduced 74.6% in 5 min and 82.05% in 24 h. The treatments on macrophages for 24 h promoted a maximum reduction by 14,5% for groups of extracts associations. On multispecies biofilm, Z75%+J25% reduced 84.3% in 24 h. In conclusion association of glycolic extracts provided therapeutic effect, demonstrated antimicrobial activity and low cytotoxicity.


Subject(s)
Juglans , Staphylococcal Infections , Zingiber officinale , Animals , Mice , Staphylococcus epidermidis , Staphylococcus aureus , Propionibacterium acnes , Staphylococcal Infections/drug therapy , Biofilms
3.
Int J Nurs Knowl ; 33(2): 108-115, 2022 Apr.
Article in English | MEDLINE | ID: mdl-34302723

ABSTRACT

PURPOSE: To analyze the short-term survival of the nursing diagnosis of neonatal hyperbilirubinemia in hospitalized neonates within the first 24 h of life and over a maximum of 7 days. METHODS: A prospective open cohort study with a longitudinal design was developed with 120 newborns during the first 24 h of life. The survival rate after a nursing diagnosis of neonatal hyperbilirubinemia was analyzed for 7 days. FINDINGS: The number of new cases of neonatal hyperbilirubinemia during the follow-up was 82 (RR: 90.1%, daily incidence rate: 34.17%). The greatest manifestation of the diagnosis occurred in the first three days (n = 97). The median diagnostic survival time was 2 days (95% CI: 2-2). Yellow-orange skin color (RR = 8.08), yellow mucous membranes (RR = 2.05), yellow sclera (RR = 1.99), and female gender (RR = 1.36) had the highest risk ratios. CONCLUSIONS: A rapid impairment of neonatal hyperbilirubinemia in hospitalized neonates was observed. Some clinical indicators were associated with an increased risk for this diagnosis. IMPLICATIONS FOR NURSING PRACTICE: Studies on the prognostic capacity of the clinical indicators of nursing diagnoses like neonatal hyperbilirubinemia strengthen the clinical reasoning of nurses and subsidize diagnostic inferences and accurate clinical decisions.


Subject(s)
Hyperbilirubinemia, Neonatal , Nursing Diagnosis , Cohort Studies , Female , Humans , Hyperbilirubinemia, Neonatal/diagnosis , Hyperbilirubinemia, Neonatal/epidemiology , Infant, Newborn , Prospective Studies , Survival Analysis
4.
Braz J Microbiol ; 53(1): 51-62, 2022 Mar.
Article in English | MEDLINE | ID: mdl-34727360

ABSTRACT

Medically important arboviruses such as dengue virus (DENV), Zika virus (ZIKV), and chikungunya virus (CHIKV) are primarily transmitted by the globally distributed mosquito Aedes aegypti. Increasing evidence suggests that the transmission of some viruses can be influenced by mosquito-specific and mosquito-borne viruses. Advancements in high-throughput sequencing (HTS) and bioinformatics have expanded our knowledge on the richness of viruses harbored by mosquitoes. HTS was used to characterize the presence of virus sequences in wild-caught adult Ae. aegypti from Tocantins (TO) state, Brazil. Samples of mosquitoes were collected in four cities of Tocantins state and submitted to RNA isolation, followed by sequencing at an Illumina HiSeq platform. Our results showed initially by Krona the presence of 3% of the sequenced reads belonging to the viral database. After further analysis, the virus sequences were found to have homology to two viral families found in insects Phenuiviridae and Metaviridae. Three possible viral strains including putative new viruses were detected and named Phasi Charoen-like phasivirus isolate To-1 (PCLV To-1), Aedes aegypti To virus 1 (AAToV1), and Aedes aegypti To virus 2 (AAToV2). The results presented in this work contribute to the growing knowledge about the diversity of viruses in mosquitoes and might be useful for future studies on the interaction between insect-specific viruses and arboviruses.


Subject(s)
Aedes , Zika Virus Infection , Zika Virus , Adult , Animals , Brazil , Humans , Mosquito Vectors , Satellite Viruses
5.
Arch Virol ; 167(2): 345-354, 2022 Feb.
Article in English | MEDLINE | ID: mdl-34839419

ABSTRACT

Baculoviruses are circular double-stranded DNA viruses that infect insects and are widely used as the baculoviral expression vectors (BEVs), which provide a eukaryotic milieu for heterologous expression. The most frequently used vector is based on Autographa californica multiple nucleopolyhedrovirus (AcMNPV). However, purification of recombinant proteins produced using BEVs is laborious, time-consuming, and often expensive. Numerous strategies have been explored to facilitate purification of heterologous proteins, such as fusion with occlusion body (OBs)-forming proteins like polyhedrin (Polh). Baculoviruses produce OBs in the late stages of infection to protect the virion in the cellular environment, and the main protein responsible for OB formation is Polh. In this study, we investigated the effect of fusing the gene that encodes the surface antigen (S-HBsAg) of hepatitis B virus (HBV) to either the N- or C-terminus of the AcMNPV Polh. The production of recombinant viruses and recombinant proteins was confirmed, and the ability to form chimeric S-HBsAg-containing OBs was accessed by light and scanning electron microscopy of infected cells. The fusion was found to affect the shape and size of the OBs when compared to wild-type OBs, with the N-terminal fusion producing less-amorphous OBs than the C-terminal construct. In addition, the N-terminal construct gave higher levels of expression than the C-terminal construct. Quantitative and qualitative immunoassays with human serum or plasma antibodies against HBsAg showed that the two forms of the antigen reacted differently. Although both reacted with the antibody, the N-terminal fusion protein reacted with more sensitivity (2.27-fold) and is therefore more suitable for quantitative assays than the C-terminal version. In summary, the BEVs represents a promising tool for the production of reagents for the diagnosis of HBV infection.


Subject(s)
Baculoviridae , Hepatitis B virus , Animals , Antigens, Surface , Baculoviridae/genetics , Hepatitis B Surface Antigens/genetics , Hepatitis B virus/genetics , Humans , Insecta
6.
J Virol Methods ; 299: 114341, 2022 01.
Article in English | MEDLINE | ID: mdl-34699776

ABSTRACT

The COVID-19 pandemic has demanded a range of biotechnological products for detection of SARS-CoV-2 variants and evaluation of human seroconversion after infection or vaccination. In this work, we describe an easy pipeline for expression of SARS-CoV-2 nucleocapsid (N) protein in insect cells followed by its purification via affinity chromatography. The N gene was cloned into the genome of Autographa californica multiple nucleopolyhedrovirus (AcMNPV) via transposition and the resulting recombinant baculovirus was used for infection of lepidopteran Sf9 cells adapted to high-density suspension. Using Tris-HCl pH 8.0 buffer as mobile phase and eluting bound proteins with 175 mM imidazole as part of a three-step gradient, an average of 1 mg N protein could be purified from each 50 mg of total protein from clarified supernatant. Such protein amount allows the manufacturing of serological tests and the development of basic studies on cellular responses to SARS-CoV-2.


Subject(s)
COVID-19 , SARS-CoV-2 , Animals , Humans , Insecta , Nucleocapsid , Nucleocapsid Proteins/genetics , Pandemics
7.
J Gen Virol ; 102(12)2021 12.
Article in English | MEDLINE | ID: mdl-34878970

ABSTRACT

Although RNA viruses have high mutation rates, host cells and organisms work as selective environments, maintaining the viability of virus populations by eliminating deleterious genotypes. In serial passages of RNA viruses in a single cell line, most of these selective bottlenecks are absent, with no virus circulation and replication in different tissues or host alternation. In this work, Aedes aegypti Aag-2 cells were accidentally infected with Chikungunya virus (CHIKV) and Mayaro virus (MAYV). After numerous passages to achieve infection persistency, the infectivity of these viruses was evaluated in Ae. albopictus C6/36 cells, African green monkey Vero cells and primary-cultured human fibroblasts. While these CHIKV and MAYV isolates were still infectious to mosquito cells, they lost their ability to infect mammalian cells. After genome sequencing, it was observed that CHIKV accumulated many nonsynonymous mutations and a significant deletion in the coding sequence of the hypervariable domain in the nsP3 gene. Since MAYV showed very low titres, it was not sequenced successfully. Persistently infected Aag-2 cells also accumulated high loads of short and recombinant CHIKV RNAs, which seemed to have been originated from virus-derived DNAs. In conclusion, the genome of this CHIKV isolate could guide mutagenesis strategies for the production of attenuated or non-infectious (to mammals) CHIKV vaccine candidates. Our results also reinforce that a paradox is expected during passages of cells persistently infected by RNA viruses: more loosening for the development of more diverse virus genotypes and more pressure for virus specialization to this constant cellular environment.


Subject(s)
Chikungunya virus/growth & development , Chikungunya virus/genetics , Genome, Viral/genetics , Alphavirus/genetics , Alphavirus/growth & development , Animals , Cell Line , Culicidae , Host Specificity , Humans , Mammals , Mutation , RNA, Viral/genetics , Viral Load/genetics , Viral Nonstructural Proteins/genetics , Virus Replication/genetics
8.
Arch Virol ; 166(10): 2865-2868, 2021 Oct.
Article in English | MEDLINE | ID: mdl-34292374

ABSTRACT

A putative new virus with sequence similarity to members of the genus Cavemovirus in the family Caulimoviridae was identified in wild chicory (Cichorium intybus) by next-generation sequencing (NGS). The putative new virus was tentatively named "chicory mosaic cavemovirus" (ChiMV), and its genome was determined to be 7,775 nucleotides (nt) long with the typical genome organization of cavemoviruses. ORF1 encodes a putative coat protein/movement polyprotein (1,278 aa), ORF2 encodes a putative replicase (650 aa), and ORF3 encodes a putative transactivator factor (384 aa). The first two putative proteins have 46.2% and 68.7% amino acid sequence identity to the CP/MP protein (YP_004347414) and replicase (YP_004347415), respectively, of sweet potato collusive virus (SPCV). ORF3 encodes a protein with 38.5% amino acid sequence identity to the putative transactivator factor (NP_056849) of cassava vein mosaic virus (CsVMV). The new putative viral genome and those of three cavemoviruses (epiphyllum virus 4 [EpV-4], SPCV, and CsVMV) differ by 24-27% in the nt sequence of the replicase gene, which exceeds the species demarcation cutoff (>20%) for the family.


Subject(s)
Caulimoviridae/genetics , Cichorium intybus/virology , Amino Acid Sequence , Caulimoviridae/classification , Genome, Viral/genetics , Open Reading Frames/genetics , Phylogeny , Plant Diseases/virology , Plant Leaves/virology , RNA, Viral/genetics , Species Specificity , Viral Proteins/genetics
9.
Biomed Pharmacother ; 135: 111186, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33395606

ABSTRACT

Trypanosoma cruzi is a protozoan parasite that causes Chagas disease, a neglected tropical disease that is endemic in Latin America and spreading worldwide due to globalization. The current treatments are based on benznidazole and nifurtimox; however, these drugs have important limitations and limited efficacy during the chronic phase, reinforcing the necessity of an alternative chemotherapy. For the last 30 years, our group has been evaluating the biological activity of naphthoquinones and derivatives on T. cruzi, and of the compounds tested, N1, N2 and N3 were found to be the most active in vitro. Here, we show the synthesis of a novel ß-lapachone-derived naphthoimidazolium named N4 and assess its activity on T. cruzi stages and the mechanism of action. The new compound was very active on all parasite stages (IC50/24 h in the range of 0.8-7.9 µM) and had a selectivity index of 5.4. Mechanistic analyses reveal that mitochondrial ROS production begins after short treatment starts and primarily affects the activity of complexes II-III. After 24 h treatment, a partial restoration of mitochondrial physiology (normal complexes II-III and IV activities and controlled H2O2 release) was observed; however, an extensive injury in its morphology was still detected. During treatment with N4, we also observed that trypanothione reductase activity increased in a time-dependent manner and concomitant with increased oxidative stress. Molecular docking calculations indicated the ubiquinone binding site of succinate dehydrogenase as an important interaction point with N4, as with the FMN binding site of dihydroorotate dehydrogenase. The results presented here may be a good starting point for the development of alternative treatments for Chagas disease and for understanding the mechanism of naphthoimidazoles in T. cruzi.


Subject(s)
Chagas Disease/drug therapy , Electron Transport Chain Complex Proteins/metabolism , Energy Metabolism/drug effects , Mitochondria/drug effects , Naphthoquinones/pharmacology , Protozoan Proteins/metabolism , Trypanocidal Agents/pharmacology , Trypanosoma cruzi/drug effects , Chagas Disease/enzymology , Chagas Disease/parasitology , Dihydroorotate Dehydrogenase , Mitochondria/enzymology , Mitochondria/ultrastructure , Mitochondrial Swelling/drug effects , Oxidoreductases Acting on CH-CH Group Donors/metabolism , Reactive Oxygen Species/metabolism , Succinate Dehydrogenase/metabolism , Trypanosoma cruzi/enzymology , Trypanosoma cruzi/growth & development , Trypanosoma cruzi/ultrastructure
10.
Arch Virol ; 165(12): 2993-2997, 2020 Dec.
Article in English | MEDLINE | ID: mdl-32975676

ABSTRACT

The genomes of two putative new RNA viruses (macula-like virus and bunya-like virus) were identified in total RNA extracted from dead eucalyptus snout beetles (Gonipterus spp.) from a laboratory colony. However, only bunya-like virus was detected in field-collected insects. The macula-like virus has a monopartite single-stranded RNA genome that contains three open reading frames (ORFs) encoding an RNA-dependent RNA polymerase (RdRp), a capsid protein (CP), protein with unknown function. The bunya-like virus genome was predicted to consist of two RNA segments: a large segment (L) encoding a single protein (RdRp) and a small segment (S) encoding a putative nucleocapsid protein.


Subject(s)
Genome, Viral , Phylogeny , RNA Viruses/classification , Weevils/virology , Animals , Open Reading Frames , RNA Viruses/isolation & purification , RNA, Viral/genetics , RNA-Dependent RNA Polymerase/genetics , Viral Proteins/genetics
11.
J Gen Virol ; 101(6): 667-675, 2020 06.
Article in English | MEDLINE | ID: mdl-32375954

ABSTRACT

The cassava hornworm Erinnyis ello ello (Lepidoptera: Sphingidae) is an important pest in Brazil. This insect feeds on host plants of several species, especially Manihot esculenta (cassava) and Hevia brasiliensis (rubber tree). Cassava hornworm outbreaks are quite common in Brazil and can cause great impact over crop production. Granulare and polyhedral-shaped occlusion bodies (OBs) were observed in extracts of dead E. ello larvae from rubber-tree plantations by light and scanning electron microscopy (SEM), suggesting a mixed infection. The polyhedral-shaped OB surface revealed indentations that resemble those found in cypovirus polyhedra. After OB nucleic acid extraction followed by cDNA production and Illumina deep-sequencing analysis, the results confirmed for the presence of a putative novel cypovirus that carries ten segments and also a betabaculovirus (Erinnyis ello granulovirus, ErelGV). Phylogenetic analysis of the predicted segment 1-enconded RdRP showed that the new cypovirus isolate is closely related to a member of species Cypovirus 2, which was isolated from Inachis io (Lepidoptera: Nymphalidae). Therefore, we named this new isolate Erinnyis ello cypovirus 2 (ErelCPV-2). Genome in silico analyses showed that ErelCPV-2 segment 8 (S8) has a predicted amino acid identity of 35.82 % to a hypothetical protein of betabaculoviruses. This putative protein has a cGAMP-specific nuclease domain related to the poxvirus immune nucleases (poxins) from the 2',3'-cGAMP-degrading enzyme family.


Subject(s)
Coinfection/genetics , Deoxyribonucleases/genetics , Granulovirus/genetics , Poxviridae/genetics , Reoviridae/genetics , Animals , Brazil , Cyclic GMP/genetics , Genome, Viral/genetics , Larva/virology , Lepidoptera/virology , Moths/virology , Occlusion Bodies, Viral/genetics , Phylogeny
12.
Braz J Microbiol ; 51(2): 827-835, 2020 Jun.
Article in English | MEDLINE | ID: mdl-31907798

ABSTRACT

Bovine alphaherpesvirus type 5 (BoHV-5) is one of the main agents responsible for meningoencephalitis in cattle in Brazil, causing significant economic losses. It is known that other viruses of the Herpesviridae family such as Bovine alphaherpesvirus type 1, Swine alphaherpesvirus type 1, and the Human alphaherpesvirus types 1 and 2 encode genes homologous to BoHV-5, with recognized action in the control of apoptosis. The objective of this work was to express the BoHV-5 US3 gene in a baculovirus-based expression system for the production of the serine/threonine kinase protein and to evaluate its activity in the control of apoptosis in vitro. A recombinant baculovirus derived from the Autographa californica multiple nucleopolyhedrovirus (AcMNPV) containing the US3 gene and a deletion in the baculovirus anti-apoptotic p35 gene was constructed using the Bac-to-Bac™ system. This recombinant baculovirus was used to evaluate the anti-apoptotic activity of the recombinant US3 protein in insect cells comparing with two other AcMNPV recombinants, one containing a functional copy of the AcMNPV anti-apoptotic p35 gene and an AcMNPV p35 knockout virus with the anti-apoptotic iap-3 gene from Anticarsia gemmatalis multiple nucleopolyhedrovirus (AgMNPV). We found that the caspase level was higher in insect cells infected with the US3-contanining recombinant virus than in cells infected with the AcMNPV recombinants containing the p35 and iap-3 genes. These results indicate that the BoHV-5 US3 protein kinase gene is not able to block apoptosis in insect cells induced by the infection of a p35 knockout AcMNPV.


Subject(s)
Alphaherpesvirinae/enzymology , Apoptosis , Baculoviridae/chemistry , Baculoviridae/genetics , Protein Kinases/metabolism , Viral Proteins/genetics , Alphaherpesvirinae/genetics , Animals , Brazil , Cattle , Nucleopolyhedroviruses/genetics , Protein Kinases/genetics , Recombinant Proteins , Sf9 Cells , Spodoptera , Virus Replication
13.
Virology ; 534: 72-79, 2019 08.
Article in English | MEDLINE | ID: mdl-31207441

ABSTRACT

An analysis of transcriptomes from the antennae of the three South American stink bugs (Euschistus heros, Chinavia ubica, and Dichelops melacanthus) revealed the presence of picorna-like virus genome-length RNAs with high sequence identity to the genome of Halyomorpha halys virus (HhV), originally discovered in the transcriptome of the brown marmorated stink bug, Halyomorpha halys. Features of the genome, phylogenetic relationships to other viruses, and the appearances of virus-like particles isolated from host stink bugs all confirm that these viruses are iflaviruses and isolates of an undescribed species. Iflavirus RNAs were present at high levels (40%-90% of transcriptome reads) in the stink bug antennal transcriptomes. In whole-insect transcriptomes of H. halys, HhV reads were >500-fold more abundant in adults than in nymphs. We identified from field population a subject of species E. heros infected by this iflavirus. The results of the analysis suggest that these iflaviruses are able to produce large quantities of their RNAs without causing any obvious pathology to their hosts.


Subject(s)
Heteroptera/virology , Insect Viruses/isolation & purification , Animals , Genome, Viral , Heteroptera/classification , Heteroptera/genetics , Insect Viruses/classification , Insect Viruses/genetics , Phylogeny , RNA, Viral/genetics
14.
Arch Virol ; 164(6): 1677-1682, 2019 Jun.
Article in English | MEDLINE | ID: mdl-30955090

ABSTRACT

We describe an unexpected feature observed for the heterologous expression of the Thyrinteina arnobia cypovirus polyhedrin from a recombinant baculovirus infection in different insect cell lines. The in cellulo-formed crystals varied in size and shape depending on the cell line. Crystals formed in Trichoplusia ni-derived cells were cubic (0.1-2 µm) and localized in both the nucleus and cytoplasm, whereas those formed in Spodoptera frugiperda-derived cells were ovate and ellipsoidal (0.1-3 µm) and also localized in both the nucleus and cytoplasm. The molecular basis for differences in the morphology, size, and location of cypovirus occlusion bodies is unclear, and cellular proteins might play a role in their formation and location.


Subject(s)
Baculoviridae/genetics , Occlusion Body Matrix Proteins/metabolism , Recombinant Proteins/metabolism , Reoviridae/metabolism , Spodoptera/cytology , Animals , Baculoviridae/metabolism , Cell Line , Cell Nucleus/metabolism , Cell Nucleus/virology , Crystallization , Cytoplasm/metabolism , Cytoplasm/virology , Microscopy, Electron, Scanning , Occlusion Body Matrix Proteins/genetics , Reoviridae/genetics , Sf9 Cells , Spodoptera/virology
15.
PeerJ ; 7: e6285, 2019.
Article in English | MEDLINE | ID: mdl-30671312

ABSTRACT

Plant vegetative propagation strategies for agricultural crops cause the accumulation of viruses, resulting in the formation of virus complexes or communities. The cultivation of garlic is based on vegetative propagation and more than 13 virus species from the genera Potyvirus, Allexivirus and Carlavirus have been reported. Aiming for an unbiased identification of viruses from a garlic germplasm collection in Brazil, total RNA from eight garlic cultivars was sequenced by high-throughput sequencing (HTS) technology. Although most viruses found in this study were previously reported, one of them did not belong to any known genera. This putative new virus was found in seven out of eight garlic cultivars and phylogenetic data positioned it as representative of an independent evolutionary lineage within family Betaflexiviridae. This virus has been tentatively named garlic yellow mosaic-associated virus (GYMaV), sharing highest nucleotide identities with African oil palm ringspot virus (genus Robigovirus) and potato virus T (genus Tepovirus) for the replicase gene, and with viruses classified within genus Foveavirus for the coat protein gene. Due to its high frequency in garlic cultivars, GYMaV should be considered in upcoming surveys of pathogens in this crop and in the development of virus-free garlic plants.

16.
Eur J Med Chem ; 135: 213-229, 2017 Jul 28.
Article in English | MEDLINE | ID: mdl-28453995

ABSTRACT

Cardiovascular diseases (CVDs) account for over 17 million deaths globally each year, with atherosclerosis as the underlying cause of most CVDs. Herein we describe the synthesis and in vitro mechanistic evaluation of novel N'-benzylidene-carbohydrazide-1H-pyrazolo[3,4-b]pyridines (3-22) designed as non-anionic antiplatelet agents and presenting a 30-fold increase in potency compared to aspirin. The mechanism underlying their antiplatelet activity was elucidated by eliminating potential targets through a series of in vitro assays including light transmission aggregometry, clot retraction, and quantitative ELISA, further identifying the reduction in biosynthesis of thromboxane B2 as their main mechanism of action. The intrinsic fluorescence of the compounds permits their binding to platelet membranes to be readily monitored. In silico structure-activity relationship, molecular docking and dynamics studies support the biological profile of the series revealing the molecular basis of their activity and their potential as future molecular therapeutic agents.


Subject(s)
Benzylidene Compounds/pharmacology , Blood Platelets/drug effects , Hydrazines/pharmacology , Platelet Aggregation Inhibitors/pharmacology , Pyrazoles/pharmacology , Pyridines/pharmacology , Benzylidene Compounds/chemistry , Dose-Response Relationship, Drug , Humans , Hydrazines/chemistry , Molecular Docking Simulation , Molecular Structure , Platelet Aggregation Inhibitors/chemical synthesis , Platelet Aggregation Inhibitors/chemistry , Pyrazoles/chemistry , Pyridines/chemistry , Structure-Activity Relationship
17.
J Invertebr Pathol ; 130: 136-40, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26254043

ABSTRACT

Opsiphanes invirae (Lepidopera: Nymphalidae) is a common pest of the African oil palm tree (Elaeis guineensis) in Brazil. Dead larvae were collected in canopy of oil palm trees cultivated in the amazon region (Para State) and analyzed for viral infection. Electron microscopy of caterpillar extracts showed an icosahedral picorna-like virus particle with 30nm in diameter. Total RNA extracted from partially purified virus particles was sequenced. A contig of 10,083 nucleotides (nt) was identified and showed to encode one single predicted polyprotein with 3185 amino acid residues. Phylogenetic analysis showed that the new virus was closely related to another lepidopteran infective virus Spodoptera exigua iflavirus 1(SeIV-1), with 35% amino acid pairwise identity. The novel virus fulfils all ICTV requirements for a new iflavirus species and was named Opsiphanes invirae Iflavirus 1 (OilV-1).


Subject(s)
Genome, Viral/genetics , Lepidoptera/virology , Picornaviridae/physiology , Picornaviridae/ultrastructure , Animals , Base Sequence , Microscopy, Electron, Transmission , Molecular Sequence Data , Phylogeny
18.
Basic Clin Pharmacol Toxicol ; 108(2): 115-21, 2011 Feb.
Article in English | MEDLINE | ID: mdl-20735790

ABSTRACT

Several studies in the Northeastern region of Brazil have demonstrated an association between hypertension in adult populations and prenatal and postnatal undernutrition. The central hypothesis we proposed was that hypertension could be favoured by programmed alterations in branches of the renal arachidonic pathway and consequently in counter-balancing the renin angiotensin system, especially during treatments with cyclooxygenase inhibitors. We assessed the influence of subchronic (21 days) and acute administration of nimesulide, a preferential cyclooxygenase-2 (COX-2) inhibitor, on mean blood pressure (MAP), renal blood flow (RBF), glomerular filtration rate (GFR) and urinary output (U(v)) in adult rats that were prenatally undernourished. Undernutrition per se led to the onset of mild hypertension in adult offspring, whereas subchronic nimesulide treatment increased MAP in control and elicited further augmentation in undernourished animals. The drug (i) decreased RBF and GFR in controls by 50%, whereas no effect was detected in the undernourished group, and (ii) increased U(v) by 25% in controls, an effect that was potentiated by 200% in programmed animals. In contrast, acute nimesulide administration decreased U(v) , with the hypertensive effect of the drug being potentiated during dehydration. These findings demonstrate that prenatal nutritional programming differentially modulates adult renovascular responses to nimesulide in the cortex and medulla, which may exacerbate the deleterious effects of COX-2 inhibition in the kidney.


Subject(s)
Cyclooxygenase 2 Inhibitors/pharmacology , Hypertension, Renovascular/complications , Kidney/physiopathology , Malnutrition/complications , Prenatal Nutritional Physiological Phenomena , Sulfonamides/pharmacology , Animals , Blood Pressure , Brazil , Cyclooxygenase 2/metabolism , Female , Glomerular Filtration Rate , Male , Malnutrition/physiopathology , Oxidative Stress , Pregnancy , Rats , Rats, Wistar , Renal Circulation
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