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1.
Arch Insect Biochem Physiol ; 116(3): e22125, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38973236

RESUMO

Insect pest control can be achieved by the application of RNA interference (RNAi), a key molecular tool in functional genomics. Whereas most RNAi research has focused on insect pests, few studies have been performed on natural enemies. Validating the efficacy of RNAi in natural enemies is crucial for assessing its safety and enabling molecular research on these organisms. Here, we assessed the efficacy of RNAi in the ladybird beetle Eriopis connexa Germar (Coleoptera: Coccinellidae), focusing on genes related to reproduction, such as vitellogenin (Vg) and its receptor (VgR). In the transcriptome of E. connexa, we found one VgR (EcVgR) and two Vg genes (EcVg1 and EcVg2). These genes have been validated by in silico analyses of functional domains and evolutionary relationships. Five-day-old females were injected with 500 ng/µL of a specific double-stranded RNA (dsRNA) (dsEcVg1, dsEcVg2, or dsEcVgR) for RNAi tests, while nonspecific dsRNA (dsGFP or dsAgCE8.1) was used as a control. Interestingly, dsEcVg2 was able to knockdown both Vg genes, while dsEcVg1 could silence only EcVg1. Additionally, the viability of the eggs was significantly reduced when both Vg genes were knocked down at the same time (after treatment with dsEcVg2 or "dsEcVg1+dsEcVg2"). Ultimately, malformed, nonviable eggs were produced when EcVgR was silenced. Interestingly, no dsRNA treatment had an impact on the quantity of eggs laid. Therefore, the feasibility of RNAi in E. connexa has been confirmed, suggesting that this coccinellid is an excellent Neotropical model for molecular research on natural enemies and for studying RNAi nontarget effects.


Assuntos
Besouros , Técnicas de Silenciamento de Genes , Interferência de RNA , Animais , Besouros/genética , Feminino , Vitelogeninas/genética , Vitelogeninas/metabolismo , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Reprodução/genética , RNA de Cadeia Dupla/genética , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/metabolismo , Proteínas do Ovo/genética , Proteínas do Ovo/metabolismo , Controle Biológico de Vetores
2.
Pestic Biochem Physiol ; 186: 105166, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35973772

RESUMO

The efficiency of RNAi technology in insects varies considerably, particularly in lepidopterans. An important limiting factor of RNAi-mediated gene silencing is the degradation of dsRNA by insect nucleases before cellular uptake. To date, few studies have reported effective gene knockdown in the sugarcane borer Diatraea saccharalis. However, yielding contradictory results when using oral delivery. Further, the RNAi efficiency in D. saccharalis and presumed activity of gut nucleases remain poorly understood. Therefore, we investigated whether gene silencing was feasible via dsRNA feeding in D. saccharalis. Two different genes were tested, juvenile hormone esterase (DsJHE) and chitin synthase 1 (DsCHS1). Discrete knockdown was verified only for DsCHS1 with high dsRNA dosages and long exposure times. Neither mortality nor abnormal phenotypes were observed after treatment with any tested dsRNA. It was also verified that dsRNAs were quickly degraded when incubated with gut juice. Furthermore, we identified four possible nucleases that could reduce the knockdown efficiency in D. saccharalis. Three of them had the endonuclease_NS domain (DsNucleases), and one had the PIN domain (DsREase), with REase-like genes being scarcely represented in databanks. We further remark that DsNuclease1 and DsREase are highly expressed in the larval gut, and DsREase was upregulated as insects were fed with artificial diet (without dsRNA), and also when injected with dsRNA. Conversely, no nuclease was triggered when insects were fed with a sucrose droplet containing dsRNA. Thus, our findings suggest that nuclease activity within the gut is one of the possible reasons for the inefficiency of RNAi in D. saccharalis. Our data may shed light on the challenges to overcome when introducing RNAi as a strategy for controlling lepidopteran pests.


Assuntos
Mariposas , RNA de Cadeia Dupla , Animais , Endonucleases/genética , Técnicas de Silenciamento de Genes , Mariposas/genética , Interferência de RNA , RNA de Cadeia Dupla/genética
3.
Planta Med ; 87(1-02): 6-23, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33348409

RESUMO

Natural products are a valuable source of biologically active compounds and continue to play an important role in modern drug discovery due to their great structural diversity and unique biological properties. Brazilian biodiversity is one of the most extensive in the world and could be an effective source of new chemical entities for drug discovery. Mosquitoes are vectors for the transmission of dengue, Zika, chikungunya, yellow fever, and many other diseases of public health importance. These diseases have a major impact on tropical and subtropical countries, and their incidence has increased dramatically in recent decades, reaching billions of people at risk worldwide. The prevention of these diseases is mainly through vector control, which is becoming more difficult because of the emergence of resistant mosquito populations to the chemical insecticides. Strategies to provide efficient and safe vector control are needed, and secondary metabolites from plant species from the Brazilian biodiversity, especially Cerrado, that are biologically active for mosquito control are herein highlighted. Also, this is a literature revision of targets as insights to promote advances in the task of developing active compounds for vector control. In view of the expansion and occurrence of arboviruses diseases worldwide, scientific reviews on bioactive natural products are important to provide molecular models for vector control and contribute with effective measures to reduce their incidence.


Assuntos
Aedes , Infecção por Zika virus , Zika virus , Animais , Brasil , Modelos Moleculares , Controle de Mosquitos , Mosquitos Vetores
4.
New Phytol ; 225(1): 430-447, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31505035

RESUMO

Galls induced by plant-parasitic nematodes involve a hyperactivation of the plant mitotic and endocycle machinery for their profit. Dedifferentiation of host root cells includes drastic cellular and molecular readjustments. In such a background, potential DNA damage in the genome of gall cells is evident. We investigated whether DNA damage checkpoint activation followed by DNA repair occurred, or was eventually circumvented, in nematode-induced galls. Galls display transcriptional activation of the DNA damage checkpoint kinase WEE1, correlated with its protein localization in the nuclei. The promoter of the stress marker gene SMR7 was evaluated under the WEE1-knockout background. Drugs inducing DNA damage and a marker for DNA repair, PARP1, were used to understand the mechanisms for coping with DNA damage in galls. Our functional study revealed that gall cells lacking WEE1 conceivably entered mitosis prematurely, disturbing the cell cycle despite the loss of genome integrity. The disrupted nuclei phenotype in giant cells hinted at the accumulation of mitotic defects. In addition, WEE1-knockout in Arabidopsis and downregulation in tomato repressed infection and reproduction of root-knot nematodes. Together with data on DNA-damaging drugs, we suggest a conserved function for WEE1 in controlling G1/S cell cycle arrest in response to a replication defect in galls.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/enzimologia , Arabidopsis/parasitologia , Ciclo Celular , Tumores de Planta/parasitologia , Proteínas Serina-Treonina Quinases/metabolismo , Tylenchoidea/fisiologia , Animais , Arabidopsis/genética , Ciclo Celular/genética , Núcleo Celular/metabolismo , Dano ao DNA , Regulação da Expressão Gênica de Plantas , Técnicas de Inativação de Genes , Células Gigantes/citologia , Glucuronidase/metabolismo , Solanum lycopersicum/genética , Mitose , Plantas Geneticamente Modificadas , Regiões Promotoras Genéticas , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
5.
Chem Pharm Bull (Tokyo) ; 66(1): 61-64, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29311513

RESUMO

Several applications have been proposed for tyrosinase inhibitors in the pharmaceutical, food bioprocessing, and environmental industries. However, only a few compounds are known to serve as effective tyrosinase inhibitors. This study evaluated the tyrosinase-related activity of resorcinol (1), orcinol (2) lecanoric acid (3), and derivatives of this acid (4-15). Subjected to alcoholysis, lecanoric acid (3), a depside isolated from the lichen Parmotrema tinctorum, produces orsellinic acid (2,4-dihydroxy-6-methylbenzoic acid) (4) and orsellinates (2,4-dihydroxy-6-methyl benzoates) (5-15). At 0.50 mM, methyl (5), ethyl (6), n-propyl (7), tert-butyl (11), and n-cetyl orsellinates (15) acted as tyrosinase activators, whereas n-butyl (8), iso-propyl (9), sec-butyl (10), n-pentyl (12), n-hexyl (13), and n-octyl orsellinates (14) behaved as inhibitors. Tyrosinase inhibition rose with chain elongation-n-butyl (8)

Assuntos
Agaricales/enzimologia , Inibidores Enzimáticos/farmacologia , Líquens/química , Monofenol Mono-Oxigenase/antagonistas & inibidores , Resorcinóis/farmacologia , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/química , Inibidores Enzimáticos/isolamento & purificação , Cinética , Estrutura Molecular , Monofenol Mono-Oxigenase/metabolismo , Resorcinóis/química , Resorcinóis/isolamento & purificação , Relação Estrutura-Atividade
6.
Plant Cell Environ ; 40(7): 1174-1188, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28103637

RESUMO

Cell cycle control in galls provoked by root-knot nematodes involves the activity of inhibitor genes like the Arabidopsis ICK/KRP members. Ectopic KRP1, KRP2 and KRP4 expression resulted in decreased gall size by inhibiting mitotic activity, whereas KRP6 induces mitosis in galls. Herein, we investigate the role of KRP3, KRP5 and KRP7 during gall development and compared their role with previously studied members of this class of cell cycle inhibitors. Overexpression of KRP3 and KRP7 culminated in undersized giant cells, with KRP3OE galls presenting peculiar elongated giant cells. Nuclei in KRP3OE and KRP5OE lines presented a convoluted and apparently connected phenotype. This appearance may be associated with the punctuated protein nuclear localization driven by specific common motifs. As well, ectopic expression of KRP3OE and KRP5OE affected nematode development and offspring. Decreased mitotic activity in galls of KRP3OE and KRP7OE lines led to a reduced gall size which presented distinct shapes - from more elongated like in the KRP3OE line to small rounded like in the KRP7OE line. Results presented strongly support the idea that induced expression of cell cycle inhibitors such as KRP3 and KRP7 in galls can be envisaged as a conceivable strategy for nematode feeding site control in crop species attacked by phytopathogenic nematodes.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/citologia , Proteínas de Transporte/genética , Proteínas Inibidoras de Quinase Dependente de Ciclina/genética , Tylenchoidea/patogenicidade , Animais , Arabidopsis/genética , Arabidopsis/parasitologia , Proteínas de Arabidopsis/metabolismo , Proteínas de Transporte/metabolismo , Ciclo Celular/genética , Proteínas de Ciclo Celular , Núcleo Celular/genética , Proteínas Inibidoras de Quinase Dependente de Ciclina/metabolismo , Regulação da Expressão Gênica de Plantas , Interações Hospedeiro-Parasita/genética , Leupeptinas/farmacologia , Raízes de Plantas/metabolismo , Raízes de Plantas/parasitologia , Tumores de Planta/genética , Plantas Geneticamente Modificadas , Ploidias , Regiões Promotoras Genéticas , Tylenchoidea/fisiologia
7.
Psychiatry Clin Neurosci ; 70(10): 434-441, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27278269

RESUMO

AIM: Childhood maltreatment (CM) has been related to a persistent reprograming of stress-response. Copeptin is a marker of hypothalamic-pituitary-adrenal axis activation; however, few studies have examined copeptin levels in children exposed to CM. The aim of this study was to compare serum copeptin levels in children reporting child abuse and/or neglect and children with no history of CM. METHODS: This study included 65 children with a positive history of moderate to severe CM, as reported by themselves and their parent(s) during a clinical interview, and 71 children with no history of CM as a comparison group. CM was considered moderate to severe based on the child-reported frequency of being exposed to events related to sexual abuse, physical abuse, emotional abuse, emotional neglect, and/or physical neglect. Child psychopathology symptoms were assessed using the Child Behavior Checklist (CBCL). We measured serum copeptin concentration using enzyme-linked immunosorbent assay. RESULTS: Children exposed to CM exhibited higher levels of serum copeptin compared to children without CM when controlling for sex, age, and psychiatric morbidity. The CBCL total score, including internalizing and externalizing symptoms, was higher in children with CM. We found no correlation between copeptin and CBCL scores for internalizing symptoms and externalizing symptoms. CONCLUSION: CM is associated with copeptin serum levels independently of age, sex, and symptom severity. Copeptin is a promising new biomarker for children with a history of abuse and/or neglect.


Assuntos
Maus-Tratos Infantis , Glicopeptídeos/sangue , Transtornos Mentais/sangue , Adolescente , Brasil , Criança , Feminino , Humanos , Masculino
8.
Pest Manag Sci ; 77(10): 4400-4410, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33991055

RESUMO

BACKGROUND: Insecticide resistance in arthropods is an inherited trait that has become a major cause of insect pest control failure. Monitoring the level of susceptibility and characterization of the type of resistance of key pest species aims to determine the risk of resistance selection in time to take action to mitigate control failures. Seven populations of the boll weevil, Anthonomus grandis grandis, collected from cotton fields in the Semiarid and Cerrado areas of Brazil, were screened for their resistance to malathion and beta-cyfluthrin, insecticides widely recommended for control of boll weevil and other pests. RESULTS: The levels of adult mortality were variable for beta-cyfluthrin (0-82%) but invariant (100%) for malathion. Bioassays of concentration-mortality were used to determine lethal concentrations (LCs) for each insecticide. The LC-values corroborate the lack of resistance to field rates of malathion but high levels of resistance to beta-cyfluthrin from 62.7- to 439.7-fold. Weevils resistant to beta-cyfluthrin were found through genome sequencing to possess a kdr mutation through the L1014F substitution in the voltage gated-sodium channel gene. CONCLUSIONS: This study found boll weevil resistance to beta-cyfluthrin to be not mediated by carboxylesterases, but with cross-resistance to DDT and carbaryl, and kdr mutation as the major mechanism of the resistance in our samples. Caution is recommended in further use of beta-cyfluthrin against boll weevil due to potential resistance. Monitoring studies using other boll weevil populations are recommended to determine the geographic pattern and extent of pyrethroid resistance. © 2021 Society of Chemical Industry.


Assuntos
Piretrinas , Gorgulhos , Animais , Controle de Insetos , Nitrilas/farmacologia , Piretrinas/farmacologia , Gorgulhos/genética
9.
Pest Manag Sci ; 77(9): 4054-4063, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33896113

RESUMO

BACKGROUND: The hemolymph and insect gut together have an essential role in the immune defense against microorganisms, including the production of antimicrobial peptides (AMP). AMPs are mainly induced by two specific signaling pathways, Toll and immune deficiency (IMD). Here, we characterize the expression profile of four genes from both pathways and describe the importance of AgraRelish in the immune defense of Anthonomus grandis against the entomopathogenic fungus Metarhizium anisopliae by RNA interference (RNAi). RESULTS: To characterize the pathway that is activated early during the A. grandis-M. anisopliae interaction, we assessed the expression profiles of AgraMyD88 and AgraDorsal (Toll pathway), AgraIMD and AgraRelish (IMD pathway), and several AMP genes. Interestingly, we found that IMD pathway genes are upregulated early, and Toll pathway genes are upregulated just 3 days after inoculation (DAI). Furthermore, nine AMPs were upregulated 24 h after fungus inoculation, including attacins, cecropins, coleoptericins, and defensins. AgraRelish knockdown resulted in a reduction in median lethal time (LT50 ) for M. anisopliae-treated insects of around 2 days compared to control treatments. In addition, AgraRelish remained knocked down at 3 DAI. Finally, we identified that AgraRelish knockdown increased fungal loads at 2 DAI compared to control treatments, possibly indicating a faster infection. CONCLUSIONS: Our data indicate the influence of the IMD pathway on the antifungal response in A. grandis. Combining biocontrol and RNAi could significantly improve cotton boll weevil management. Hence, AgraRelish is a potential target for the development of biotechnological tools aimed at improving the efficacy of M. anisopliae against A. grandis.


Assuntos
Metarhizium , Gorgulhos , Animais , Biotecnologia , Insetos , Metarhizium/genética , Interferência de RNA
10.
Front Physiol ; 11: 591569, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33329040

RESUMO

The cotton boll weevil, Anthonomus grandis, is the most economically important pest of cotton in Brazil. Pest management programs focused on A. grandis are based mostly on the use of chemical insecticides, which may cause serious ecological impacts. Furthermore, A. grandis has developed resistance to some insecticides after their long-term use. Therefore, alternative control approaches that are more sustainable and have reduced environmental impacts are highly desirable to protect cotton crops from this destructive pest. RNA interference (RNAi) is a valuable reverse genetics tool for the investigation of gene function and has been explored for the development of strategies to control agricultural insect pests. This study aimed to evaluate the biological role of the Laccase2 (AgraLac2) gene in A. grandis and its potential as an RNAi target for the control of this insect pest. We found that AgraLac2 is expressed throughout the development of A. grandis with significantly higher expression in pupal and adult developmental stages. In addition, the immunolocalization of the AgraLac2 protein in third-instar larvae using specific antibodies revealed that AgraLac2 is distributed throughout the epithelial tissue, the cuticle and the tracheal system. We also verified that the knockdown of AgraLac2 in A. grandis resulted in an altered cuticle tanning process, molting defects and arrested development. Remarkably, insects injected with dsAgraLac2 exhibited defects in cuticle hardening and pigmentation. As a consequence, the development of dsAgraLac2-treated insects was compromised, and in cases of severe phenotypic defects, the insects subsequently died. On the contrary, insects subjected to control treatments did not show any visible phenotypic defects in cuticle formation and successfully molted to the pupal and adult stages. Taken together, our data indicate that AgraLac2 is involved in the cuticle tanning process in A. grandis and may be a promising target for the development of RNAi-based technologies.

11.
Sci Rep ; 9(1): 12804, 2019 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-31488852

RESUMO

Coffee production is a global industry valued at approximately 173 billion US dollars. One of the main challenges facing coffee production is the management of the coffee berry borer (CBB), Hypothenemus hampei, which is considered the primary arthropod pest of coffee worldwide. Current control strategies are inefficient for CBB management. Although biotechnological alternatives, including RNA interference (RNAi), have been proposed in recent years to control insect pests, characterizing the genetics of the target pest is essential for the successful application of these emerging technologies. In this study, we employed RNA-seq to obtain the transcriptome of three developmental stages of the CBB (larva, female and male) to increase our understanding of the CBB life cycle in relation to molecular features. The CBB transcriptome was sequenced using Illumina Hiseq and assembled de novo. Differential gene expression analysis was performed across the developmental stages. The final assembly produced 29,434 unigenes, of which 4,664 transcripts were differentially expressed. Genes linked to crucial physiological functions, such as digestion and detoxification, were determined to be tightly regulated between the reproductive and nonreproductive stages of CBB. The data obtained in this study help to elucidate the critical roles that several genes play as regulatory elements in CBB development.


Assuntos
Coffea/parasitologia , Genes de Insetos , Gorgulhos/crescimento & desenvolvimento , Gorgulhos/genética , Animais , Feminino , Perfilação da Expressão Gênica , Larva/genética , Larva/crescimento & desenvolvimento , Masculino , RNA-Seq , Transcriptoma
12.
Front Plant Sci ; 8: 961, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28659939

RESUMO

Root-knot nematodes induce galls that contain giant-feeding cells harboring multiple enlarged nuclei within the roots of host plants. It is recognized that the cell cycle plays an essential role in the set-up of a peculiar nuclear organization that seemingly steers nematode feeding site induction and development. Functional studies of a large set of cell cycle genes in transgenic lines of the model host Arabidopsis thaliana have contributed to better understand the role of the cell cycle components and their implication in the establishment of functional galls. Mitotic activity mainly occurs during the initial stages of gall development and is followed by an intense endoreduplication phase imperative to produce giant-feeding cells, essential to form vigorous galls. Transgenic lines overexpressing particular cell cycle genes can provoke severe nuclei phenotype changes mainly at later stages of feeding site development. This can result in chaotic nuclear phenotypes affecting their volume. These aberrant nuclear organizations are hampering gall development and nematode maturation. Herein we report on two nuclear volume assessment methods which provide information on the complex changes occurring in nuclei during giant cell development. Although we observed that the data obtained with AMIRA tend to be more detailed than Volumest (Image J), both approaches proved to be highly versatile, allowing to access 3D morphological changes in nuclei of complex tissues and organs. The protocol presented here is based on standard confocal optical sectioning and 3-D image analysis and can be applied to study any volume and shape of cellular organelles in various complex biological specimens. Our results suggest that an increase in giant cell nuclear volume is not solely linked to increasing ploidy levels, but might result from the accumulation of mitotic defects.

13.
J Ethnopharmacol ; 204: 18-25, 2017 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-28392458

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Doliocarpus dentatus is a medicinal plant widely used in Mato Grosso do Sul State for removing the swelling pain caused by the inflammation process and for treating urine retention. AIM OF THE STUDY: The genotoxic aspects and the anti-inflammatory and antimycobacterial activity of the ethanolic extract obtained from the leaves of D. dentatus (EEDd) were investigated. MATERIALS AND METHODS: The EEDd was evaluated against Mycobacterium tuberculosis, and the compound composition was evaluated and identified by nuclear magnetic resonance (NMR). The mice received oral administration of EEDd (30-300mg/kg) in carrageenan models of inflammation, and EEDd (10-1000mg/kg) was assayed by the comet, micronucleus, and phagocytosis tests and by the peripheral leukocyte count. RESULTS: Phenols (204.04mg/g), flavonoids (89.17mg/g), and tannins (12.05mg/g) as well as sitosterol-3-O-ß-D-glucopyranoside, kaempferol 3-O-α-L-rhamnopyranoside, betulinic acid and betulin were present in the EEDd. The value of minimal inhibitory concentration (MIC) of EEDd was 62.5µg/mL. The EEDd induced a significant decrease in the edema, mechanical hypersensitivity and leukocyte migration induced by carrageenan. The comet and micronucleus tests indicated that the EEDd was not genotoxic. The EEDd also did not change the phagocytic activity or the leukocyte perLipheral count. CONCLUSIONS: The EEDd does not display genotoxicity, phagocytosis and could act as an antimycobacterial and anti-inflammatory agent. This study should contribute to ensuring the safe use of EEDd.


Assuntos
Antibacterianos/uso terapêutico , Anti-Inflamatórios/uso terapêutico , Dilleniaceae , Extratos Vegetais/uso terapêutico , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Carragenina , Ensaio Cometa , Edema/induzido quimicamente , Edema/tratamento farmacológico , Flavonoides/análise , Hiperalgesia/induzido quimicamente , Hiperalgesia/tratamento farmacológico , Leucócitos/efeitos dos fármacos , Leucócitos/imunologia , Masculino , Camundongos Endogâmicos C57BL , Testes para Micronúcleos , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/crescimento & desenvolvimento , Fagocitose/efeitos dos fármacos , Fenóis/análise , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Pleurisia/induzido quimicamente , Pleurisia/tratamento farmacológico , Pleurisia/imunologia , Taninos/análise
14.
Int. j. cardiovasc. sci. (Impr.) ; 35(1): 58-64, Jan.-Feb. 2022. tab
Artigo em Inglês | LILACS | ID: biblio-1356321

RESUMO

Abstract Background In Brazil the factors involved in the risk of death in patients with COVID-19 have not been well established. Objective To analyze whether elevations of high-sensitivity troponin I (hTnI) levels influence the mortality of patients with COVID-19. Methods Clinical and laboratory characteristics of hospitalized patients with COVID-19 were collected upon hospital admission. Univariate and binary logistic regression analyzes were performed to assess the factors that influence mortality. P-value<0.05 was considered significant. Results This study analyzed192 patients who received hospital admission between March 16 and June 2, 2020 and who were discharged or died by July 2, 2020. The mean age was 70±15 years, 80 (41.7%) of whom were women. In comparison to those who were discharged, the 54 (28.1%) who died were older (79±12 vs 66±15years; P=0.004), and with a higher Charlson´s index (5±2 vs 3±2; P=0.027). More patients, aged≥60years (P <0.0001), Charlson´s index>1 (P=0.004), lung injury>50% in chest computed tomography (P=0.011), with previous coronary artery disease (P=0.037), hypertension (P=0.033), stroke (P=0.008), heart failure (P=0.002), lymphocytopenia (P=0.024), high D-dimer (P=0.024), high INR (P=0.003), hTnI (P<0.0001), high creatinine (P<0.0001), invasive mechanical ventilation (P<0.0001), renal replacement therapy (P<0.0001), vasoactive amine (P<0.0001), and transfer to the ICU (P=0.001), died when compared to those who were discharged. In logistic regression analysis, elevated hTnI levels (OR=9.504; 95% CI=1.281-70.528; P=0.028) upon admission, and the need for mechanical ventilation during hospitalization (OR=46.691; 95% CI=2.360-923.706; P=0.012) increased the chance of in-hospital mortality. Conclusion This study suggests that in COVID-19 disease, myocardial injury upon hospital admission is a harbinger of poor prognosis.


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Adulto Jovem , Troponina I/sangue , COVID-19/mortalidade , Miocardite/complicações , Arritmias Cardíacas/complicações , Arritmias Cardíacas/etiologia , Estudos Retrospectivos , Estudos de Coortes , COVID-19/complicações
15.
Meta Gene ; 9: 173-80, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27419079

RESUMO

Vitellogenin (Vg), a yolk protein precursor, is the primary egg nutrient source involved in insect reproduction and embryo development. The Cotton Boll weevil (CBW) Anthonomus grandis Boheman, the most important cotton pest in Americas, accumulates large amounts of Vg during reproduction. However, the precise role of this protein during embryo development in this insect remains unknown. Herein, we investigated the effects of vitellogenin (AgraVg) knockdown on the egg-laying and egg viability in A. grandis females, and also characterized morphologically the unviable eggs. AgraVg transcripts were found during all developmental stages of A. grandis, with highest abundance in females. Silencing of AgraVg culminated in a significant reduction in transcript amount, around 90%. Despite this transcriptional reduction, egg-laying was not affected in dsRNA-treated females but almost 100% of the eggs lost their viability. Eggs from dsRNA-treated females showed aberrant embryos phenotype suggesting interference at different stages of embryonic development. Unlike for other insects, the AgraVg knockdown did not affect the egg-laying ability of A. grandis, but hampered A. grandis reproduction by perturbing embryo development. We concluded that the Vg protein is essential for A. grandis reproduction and a good candidate to bio-engineer the resistance against this devastating cotton pest.

16.
3 Biotech ; 6(1): 59, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28330129

RESUMO

Plant defensins are antifungal peptides produced by the innate immune system plants developed to circumvent fungal infection. The defensin Drr230a, originally isolated from pea, has been previously shown to be active against various entomopathogenic and phytopathogenic fungi. In the present study, the activity of a yeast-expressed recombinant Drr230a protein (rDrr230a) was tested against impacting soybean and cotton fungi. First, the gene was subcloned into the yeast expression vector pPICZαA and expressed in Pichia pastoris. Resulting rDrr230a exhibited in vitro activity against fungal growth and spore germination of Fusarium tucumaniae, which causes soybean sudden death syndrome, and against Colletotrichum gossypii var. cephalosporioides, which causes cotton ramulosis. The rDrr230a IC50 corresponding to inhibition of fungal growth of F. tucumaniae and C. gossypii var. cephalosporioides was 7.67 and 0.84 µM, respectively, demonstrating moderate activity against F. tucumaniae and high potency against C. gossypii var. cephalosporioides. Additionally, rDrr230a at 25 ng/µl (3.83 µM) resulted in 100 % inhibition of spore germination of both fungi, demonstrating that rDrr230a affects fungal development since spore germination. Moreover, rDrr230a at 3 µg/µl (460.12 µM) inhibited 100 % of in vitro spore germination of the obligatory biotrophic fungus Phakopsora pachyrhizi, which causes Asian soybean rust. Interestingly, rDrr230a substantially decreased the severity of Asian rust, as demonstrated by in planta assay. To our knowledge, this is the first report of a plant defensin active against an obligatory biotrophic phytopathogenic fungus. Results revealed the potential of rDrr230a as a candidate to be used in plant genetic engineering to control relevant cotton and soybean fungal diseases.

17.
PLoS One ; 10(2): e0118231, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25706301

RESUMO

Sugarcane is a widely cultivated plant that serves primarily as a source of sugar and ethanol. Its annual yield can be significantly reduced by the action of several insect pests including the sugarcane giant borer (Telchin licus licus), a lepidopteran that presents a long life cycle and which efforts to control it using pesticides have been inefficient. Although its economical relevance, only a few DNA sequences are available for this species in the GenBank. Pyrosequencing technology was used to investigate the transcriptome of several developmental stages of the insect. To maximize transcript diversity, a pool of total RNA was extracted from whole body insects and used to construct a normalized cDNA database. Sequencing produced over 650,000 reads, which were de novo assembled to generate a reference library of 23,824 contigs. After quality score and annotation, 43% of the contigs had at least one BLAST hit against the NCBI non-redundant database, and 40% showed similarities with the lepidopteran Bombyx mori. In a further analysis, we conducted a comparison with Manduca sexta midgut sequences to identify transcripts of genes involved in digestion. Of these transcripts, many presented an expansion or depletion in gene number, compared to B. mori genome. From the sugarcane giant borer (SGB) transcriptome, a number of aminopeptidase N (APN) cDNAs were characterized based on homology to those reported as Cry toxin receptors. This is the first report that provides a large-scale EST database for the species. Transcriptome analysis will certainly be useful to identify novel developmental genes, to better understand the insect's biology and to guide the development of new strategies for insect-pest control.


Assuntos
Digestão/genética , Perfilação da Expressão Gênica/métodos , Proteínas de Insetos/genética , Lepidópteros/genética , Saccharum/parasitologia , Sequência de Aminoácidos , Animais , Antígenos CD13/genética , Etiquetas de Sequências Expressas/química , Biblioteca Gênica , Ontologia Genética , Lepidópteros/crescimento & desenvolvimento , Lepidópteros/fisiologia , Estágios do Ciclo de Vida/genética , Dados de Sequência Molecular , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos
18.
Br J Pharmacol ; 141(2): 367-73, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14691057

RESUMO

1. We have investigated the inhibitory effects of blockers of volume-activated (Cl(vol)) and calcium-activated (Cl(Ca)) chloride channels on hypotonic solution (HS)-induced contractions of rat trachea, comparing their effects with those of the voltage-dependent calcium channel (VDCC) blocker nifedpine. 2. HS elicited large, stable contractions that were partially dependent on the cellular chloride gradient; a reduction to 41.45+/-7.71% of the control response was obtained when extracellular chloride was removed. In addition, HS-induced responses were reduced to 26.8+/-5.6% of the control by 1 microm nifedipine, and abolished under calcium-free conditions, indicating a substantial requirement for extracellular calcium entry, principally via VDCCs. 3. The established Cl(vol) blockers tamoxifen (

Assuntos
Canais de Cloreto/antagonistas & inibidores , Canais de Cloreto/fisiologia , Soluções Hipotônicas/farmacologia , Contração Muscular/efeitos dos fármacos , Traqueia/efeitos dos fármacos , Animais , Masculino , Contração Muscular/fisiologia , Nifedipino/farmacologia , Ácido Niflúmico/farmacologia , Ratos , Ratos Wistar , Tamoxifeno/farmacologia , Traqueia/fisiologia
19.
J Chromatogr A ; 1035(1): 47-51, 2004 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-15117073

RESUMO

The methanolic extract of the leaves of the medicinal plant Byrsonima crassa (Malpighiaceae) contain flavonoids with antioxidant activity. They were separated in a preparative scale using high-speed counter-current chromatography. The optimum solvent system used was composed of a mixture of ethyl acetate-n-propanol-water (140:8:80 (v/v/v)) and led to a successful separation between monoglucosilated flavonoids (quercetin-3-O-alpha-L-arabinoside, quercetin-3-O-beta-D-galactoside) and the biflavonoid amentoflavone in only 3.5 h. The purities of quercetin-3-O-alpha-L-arabinoside (95 mg), quercetin-3-O-beta-D-galactoside (16 mg) and the biflavonoid amentoflavone (114 mg) were all isolated at purity over 95%. Identification was performed by 1H NMR, 13C NMR and UV analyses.


Assuntos
Distribuição Contracorrente/métodos , Flavonoides/isolamento & purificação , Malpighiaceae/química , Folhas de Planta/química , Espectrofotometria Ultravioleta
20.
Z Naturforsch C J Biosci ; 58(1-2): 47-52, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12622225

RESUMO

The new flavonoid glycoside kaempferol-3-O-alpha-L-rhamnopyranosyl(1-->2)-O-[alpha-L-rhamnopyranosyl(1-->6)]-O-beta-D-galactopyranoside-7-O-alpha-L-rhamnopyranoside was isolated together with (S)-zierin from the leaves of Zollernia ilicifolia (Fabaceae), a medicinal plant used as analgesic and antiulcerogenic effects in Brazilian Tropical Atlantic Rain Forest. The structures were established on the basis of 1H, 13C NMR and 2D NMR (COSY, HMBC, HMQC), UV, MS and IV spectra. The infusion of Zollernia ilicifolia was qualitatively compared to the infusion of the espinheiras-santas (Maytenus aquifolium and Maytenus ilicifolia) by HPLC-DAD.


Assuntos
Cycadopsida/química , Fabaceae/química , Flavonoides/química , Glicosídeos/química , Oligossacarídeos/química , Brasil , Sequência de Carboidratos , Flavonoides/isolamento & purificação , Glicosídeos/isolamento & purificação , Hidrólise , Espectroscopia de Ressonância Magnética , Medicina Tradicional , Dados de Sequência Molecular , Oligossacarídeos/isolamento & purificação , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Folhas de Planta/química , Especificidade da Espécie , Clima Tropical
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