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1.
Pharmaceuticals (Basel) ; 16(10)2023 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-37895860

RESUMO

Chikungunya virus (CHIKV) belongs to the Alphavirus genus and is responsible for significant outbreaks worldwide. Currently, there is no approved antiviral therapy against CHIKV. Bioactive peptides have great potential for new drug development. Here, we evaluated the antiviral activity of the synthetic peptide GA-Hecate and its analogs PSSct1905 and PSSct1910 against CHIKV infection. Initial screening showed that all three peptides inhibited the CHIKV replication cycle in baby hamster kidney fibroblast cells (BHK-21) and human hepatocarcinoma epithelial cells (Huh-7). GA-Hecate and its analog PSSct1905 were the most active, demonstrating suppression of viral infection by more than 91%. The analog PSSct1905 exhibited a protective effect in cells against CHIKV infection. We also observed that the analogs PSSct1905 and PSSct1910 affected CHIKV entry into both cell lines, inhibiting viral attachment and internalization. Finally, all tested compounds presented antiviral activity on the post-entry steps of CHIKV infection in all cells evaluated. In conclusion, this study highlights the potential of the peptide GA-Hecate and its analogs as novel anti-CHIKV compounds targeting different stages of the viral replication cycle, warranting the development of GA-Hecate-based compounds with broad antiviral activity.

2.
PLoS One ; 18(9): e0283817, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37676868

RESUMO

Zika virus (ZIKV) has spread all over the world since its major outbreak in 2015. This infection has been recognized as a major global health issue due to the neurological complications related to ZIKV infection, such as Guillain-Barré Syndrome and Zika virus Congenital Syndrome. Currently, there are no vaccines or specific treatments for ZIKV infection, which makes the development of specific therapies for its treatment very important. Several studies have been developed to analyze the potential of compounds against ZIKV, with the aim of finding new promising treatments. Herein, we evaluate the ability of a copaiba (Copaifera officinalis) oil nanoemulsion (CNE) to inhibit ZIKV. First, the highest non-cytotoxic concentration of 180 µg/mL was chosen since this concentration maintains 80% cell viability up to 96h after treatment with CNE in VERO cells resulted from MTT assay. The intracellular uptake assay was performed, and confirmed the internalization of the nanoemulsion in cells at all times analyzed. VERO cells were infected with ZIKV and simultaneously treated with CNE and the nanoformulation without oil (ENE) at the highest non-toxic concentration. The results evaluated by plaque assay revealed a viral inhibition of 80% for CNE and 70% for ENE. A dose-dependence assay revealed that the CNE treatment demonstrated a dose-dependent response in the viral RNA levels, whereas all ENE tested concentrations exhibited a similar degree of reduction. Taken together, our results suggest CNE as a promising nano-sized platform to be further studied for antiviral treatments.


Assuntos
Fabaceae , Infecção por Zika virus , Zika virus , Chlorocebus aethiops , Animais , Células Vero , Projetos de Pesquisa
3.
Viruses ; 15(9)2023 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-37766292

RESUMO

The SARS-CoV-2 entry into host cells is mainly mediated by the interactions between the viral spike protein (S) and the ACE-2 cell receptor, which are highly glycosylated. Therefore, carbohydrate binding agents may represent potential candidates to abrogate virus infection. Here, we evaluated the in vitro anti-SARS-CoV-2 activity of two mannose-binding lectins isolated from the Brazilian plants Canavalia brasiliensis and Dioclea violacea (ConBR and DVL). These lectins inhibited SARS-CoV-2 Wuhan-Hu-1 strain and variants Gamma and Omicron infections, with selectivity indexes (SI) of 7, 1.7, and 6.5, respectively for ConBR; and 25, 16.8, and 22.3, for DVL. ConBR and DVL inhibited over 95% of the early stages of the viral infection, with strong virucidal effect, and also protected cells from infection and presented post-entry inhibition. The presence of mannose resulted in the complete lack of anti-SARS-CoV-2 activity by ConBR and DVL, recovering virus titers. ATR-FTIR, molecular docking, and dynamic simulation between SARS-CoV-2 S and either lectins indicated molecular interactions with predicted binding energies of -85.4 and -72.0 Kcal/Mol, respectively. Our findings show that ConBR and DVL lectins possess strong activities against SARS-CoV-2, potentially by interacting with glycans and blocking virus entry into cells, representing potential candidates for the development of novel antiviral drugs.


Assuntos
Antivirais , COVID-19 , Humanos , Antivirais/farmacologia , Lectinas de Ligação a Manose , SARS-CoV-2 , Simulação de Acoplamento Molecular , Lectinas/farmacologia
4.
J Opt Soc Am A Opt Image Sci Vis ; 40(4): C101-C107, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-37132975

RESUMO

The performance of communication systems based on free-space optical links depends on external factors such as weather conditions. Among many atmospheric factors, turbulence can be the greatest challenge to performance. The characterization of atmospheric turbulence usually involves expensive equipment known as a scintillometer. This work presents a low-cost experimental setup for measuring the refractive index structure constant over water, which results in a statistical model based on weather conditions. The turbulence variations with air and water temperature, relative humidity, pressure, dew point, and different watercourse widths are analyzed for the proposed scenario.

5.
Viruses ; 15(5)2023 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-37243254

RESUMO

Chikungunya virus (CHIKV) and Zika virus (ZIKV) are important disease-causing agents worldwide. Currently, there are no antiviral drugs or vaccines approved to treat these viruses. However, peptides have shown great potential for new drug development. A recent study described (p-BthTX-I)2K [(KKYRYHLKPF)2K], a peptide derived from the Bothropstoxin-I toxin in the venom of the Bothrops jararacussu snake, showed antiviral activity against SARS-CoV-2. In this study, we assessed the activity of this peptide against CHIKV and ZIKV and its antiviral action in the different stages of the viral replication cycle in vitro. We observed that (p-BthTX-I)2K impaired CHIKV infection by interfering with the early steps of the viral replication cycle, reducing CHIKV entry into BHK-21 cells specifically by reducing both the attachment and internalization steps. (p-BthTX-I)2K also inhibited the ZIKV replicative cycle in Vero cells. The peptide protected the cells against ZIKV infection and decreased the levels of the viral RNA and the NS3 protein of this virus at viral post-entry steps. In conclusion, this study highlights the potential of the (p-BthTX-I)2K peptide to be a novel broad-spectrum antiviral candidate that targets different steps of the replication cycle of both CHIKV and ZIKV.


Assuntos
COVID-19 , Febre de Chikungunya , Vírus Chikungunya , Vírus , Infecção por Zika virus , Zika virus , Animais , Chlorocebus aethiops , Humanos , Infecção por Zika virus/tratamento farmacológico , Zika virus/genética , Células Vero , Antivirais/farmacologia , Antivirais/uso terapêutico , Replicação Viral , SARS-CoV-2 , Vírus Chikungunya/genética , Peptídeos/farmacologia , Peptídeos/uso terapêutico
6.
Viruses ; 15(3)2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36992374

RESUMO

Non-SARS-CoV-2 respiratory viral infections, such as influenza virus (FluV) and human respiratory syncytial virus (RSV), have contributed considerably to the burden of infectious diseases in the non-COVID-19 era. While the rates of co-infection in SARS-CoV-2-positive group (SCPG) patients have been determined, the burden of other respiratory viruses in the SARS-CoV-2-negative group (SCNG) remains unclear. Here, we conducted a cross-sectional study (São José do Rio Preto county, Brazil), and we collected our data using a meta-analysis to evaluate the pooled prevalence of FluV and RSV among SCNG patients. Out of the 901 patients suspected of COVID-19, our molecular results showed positivity of FluV and RSV in the SCNG was 2% (15/733) and 0.27% (2/733), respectively. Co-infection with SARS-CoV-2 and FluV, or RSV, was identified in 1.7% of the patients (3/168). Following our meta-analysis, 28 studies were selected (n = 114,318 suspected COVID-19 patients), with a pooled prevalence of 4% (95% CI: 3-6) for FluV and 2% (95% CI: 1-3) for RSV among SCNG patients were observed. Interestingly, FluV positivity in the SCNG was four times higher (OR = 4, 95% CI: 3.6-5.4, p < 0.01) than in the SCPG. Similarly, RSV positivity was significantly associated with SCNG patients (OR = 2.9, 95% CI: 2-4, p < 0.01). For subgroup analysis, cold-like symptoms, including fever, cough, sore throat, headache, myalgia, diarrhea, and nausea/vomiting, were positively associated (p < 0.05) with the SCPG. In conclusion, these results show that the pooled prevalence of FluV and RSV were significantly higher in the SCNG than in the SCPG during the early phase of the COVID-19 pandemic.


Assuntos
COVID-19 , Coinfecção , Influenza Humana , Infecções por Vírus Respiratório Sincicial , Humanos , Coinfecção/epidemiologia , COVID-19/epidemiologia , Estudos Transversais , Influenza Humana/epidemiologia , Pandemias , Infecções por Vírus Respiratório Sincicial/epidemiologia , Vírus Sincicial Respiratório Humano , SARS-CoV-2
7.
Viruses ; 14(11)2022 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-36366431

RESUMO

Wastewater-based epidemiology (WBE) is a tool involving the analysis of wastewater for chemicals and pathogens at the community level. WBE has been shown to be an effective surveillance system for SARS-CoV-2, providing an early-warning-detection system for disease prevalence in the community via the detection of genetic materials in the wastewater. In numerous nation-states, studies have indicated the presence of SARS-CoV-2 in wastewater. Herein, we report the primary time-course monitoring of SARS-CoV-2 RNA in wastewater samples in São José do Rio Preto-SP/Brazil in order to explain the dynamics of the presence of SARS-CoV-2 RNA during one year of the SARS-CoV-2 pandemic and analyze possible relationships with other environmental parameters. We performed RNA quantification of SARS-CoV-2 by RT-qPCR using N1 and N2 targets. The proportion of positive samples for every target resulted in 100% and 96.6% for N1 and N2, respectively. A mean lag of -5 days is observed between the wastewater signal and the new SARS-CoV-2-positive cases reported. A correlation was found between the air and wastewater temperatures and therefore between the SARS-CoV-2 viral titers for N1 and N2 targets. We also observed a correlation between SARS-CoV-2 viral titers and media wastewater flow for the N1 target. In addition, we observed higher viral genome copies within the wastewater samples collected on non-rainy days for the N1 target. Thus, we propose that, based on our results, monitoring raw wastewater may be a broadly applicable strategy that might contribute to resolving the pressing problem of insufficient diagnostic testing; it may represent an inexpensive and early-warning method for future COVID-19 outbreaks, mainly in lower- and middle-income countries.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , Águas Residuárias , Vigilância Epidemiológica Baseada em Águas Residuárias , COVID-19/epidemiologia , RNA Viral/genética , Brasil/epidemiologia
8.
Photodiagnosis Photodyn Ther ; 35: 102394, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34119706

RESUMO

Cervical cancer is a worldwide public health problem, and improved selective therapies and anticancer drugs are urgently needed. In recent years, emodin has attracted considerable attention due to its anti-inflammatory, antineoplastic, and proapoptotic effects. Furthermore, emodin may be used as a photosensitizing agent in photodynamic therapy. Interest in photodynamic therapy for cancer treatment has increased due to its efficiency in causing tumor cell death. This study aimed to analyze the effect of emodin combined with photodynamic therapy in cervical carcinoma cell lines. At first, emodin presented cytotoxicity in concentration and time-dependent manners in all the specific cell lines analyzed. SiHa, CaSki, and HaCaT cancer cells presented more than 80% cell viability in concentrations below 30 µmol/L. Fluorescence microscopy images showed efficient cellular uptake of emodin in all analyzed cell lines. A significant decrease in cell viability was observed in SiHa, CaSki, and HaCaT cell lines after treatment of emodin combined with photodynamic therapy. These decreases were accompanied by increased ROS production, caspase-3 activity, and fluorescence intensity of autophagic vacuoles. This suggests increased ROS production led to cell death by apoptosis and autophagy. Additionally, after the combination of emodin and photodynamic therapy in SiHa cells, we observed the overexpression of 22 target genes and downregulation of two target genes of anti-cancer drugs. These results show the promising potential for applications that combine emodin with photodynamic therapy for cervical cancer treatment.


Assuntos
Emodina , Fotoquimioterapia , Neoplasias do Colo do Útero , Apoptose , Linhagem Celular Tumoral , Emodina/farmacologia , Emodina/uso terapêutico , Feminino , Humanos , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Neoplasias do Colo do Útero/tratamento farmacológico
9.
Photodiagnosis Photodyn Ther ; 33: 102174, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33401021

RESUMO

Cervical carcinoma is the most common gynecological cancer among young and adult women. There has been increasing interest in natural sources for cervical carcinoma treatment, especially for active compounds from plant extracts as antineoplastic agents. Berberine is an example of one these promising natural products. It is a natural isoquinoline alkaloid and comes from plants, such as Berbis, Coptis, and Hydrastis. It is widely used in Chinese medicine and has demonstrated activity against various cancer cell lines. This work aims to analyze the efficiency of berberine-containing nanoemulsions as photosensitizing agents in photodynamic therapy and their interaction with cervical carcinoma cells and immortalized human keratinocyte cell line. Among all groups tested, berberine nanoemulsions combined with photodynamic therapy induced the most statistically significant phototoxicity in the evaluated cell lines. Fluorescence microscopy demonstrated that the compound was present for up to 48 h when berberine nanoemulsions were used. The reactive oxygen species assay showed an increase in reactive oxygen species in the two studied cell lines after treatment of berberine-containing nanoemulsion combined with photodynamic therapy. The autophagy trial showed significant increases in cell death when berberine-containing nanoemulsion treatment was combined with photodynamic therapy when compared to trichostatin A treatment as a positive control. However, caspase-3 activity did not significantly increase in cervical carcinoma cells and immortalized human keratinocyte cell line. The results suggest that nanoemulsions with berberine have potential for use as photosensitizing agents in photodynamic therapy to treat cervical carcinoma.


Assuntos
Berberina , Carcinoma , Fotoquimioterapia , Adulto , Apoptose , Berberina/farmacologia , Linhagem Celular Tumoral , Feminino , Humanos , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/farmacologia
10.
Rev. bras. entomol ; 63(3): 245-249, July-Sept. 2019. graf
Artigo em Inglês | LILACS | ID: biblio-1045565

RESUMO

ABSTRACT The first immature description for a South American species of the genus Chlorota Burmeister, 1844 (Melolonthidae: Rutelinae) is presented. The last larval instar and female pupa of Chlorota paulistana Ohaus, 1912 are described. Illustrations and diagnostic characters are also presented, along with additional characters for the genus, and a new state record for Pernambuco is added. With this study, two species of immatures of Chlorota are now known and their diagnostic characters and differences are here discussed.

11.
Zootaxa ; 4434(2): 369-372, 2018 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-30313190

RESUMO

Moronius Grossi Vaz-de-Mello, 2015 (Coleoptera: Scarabaeidae: Rutelinae: Rutelini) is the latest genus described within the subtribe Areodina (Grossi Vaz-de-Mello 2015). Areodina consists of 11 genera distributed throughout the New World (10 genera) and Africa (one genus) (Jameson 1990; Grossi Vaz-de-Mello 2015). Moronius is distinguished from other genera of Areodina by: 1) the pentagonal clypeal shape with the apex strongly reflexed, and 2) the hind wings with the anterior margin near RA1+2, RA1+3, and apical hinge setose. The South American genera of Areodina form a distinct clade (Jameson 1990) composed of Oplognathus MacLeay, 1819, Areoda MacLeay, 1819, and Byrsopolis Burmeister, 1844. Oplognathus and Areoda are differentiated by the presence of a forward-projecting mesoventral process, which is absent in both Byrsopolis and Moronius. These two latter genera are similar according to the characters presented in the Jameson (1990) phylogeny and are differentiated by habitus colour, shape of clypeus, and antennal club length (Grossi Vaz-de-Mello 2015).


Assuntos
Besouros , África , Animais , Cor , Filogenia
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