Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 59
Filtrar
1.
Int J Biol Macromol ; 254(Pt 1): 127741, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38287568

RESUMO

Mammaliicoccus sciuri, a commensal and pathogenic bacterium of significant clinical and veterinary relevance, expresses exfoliative toxin C (ExhC), a specific glutamyl endopeptidase belonging to the chymotrypsin family as the principal virulence factor. However, unlike most members of this family, ETs are inactive against a wide range of substrates and possess exquisite specificity for desmoglein-1 (Dsg1), a cadherin-like adhesion molecule that is crucial to maintain tissue integrity, thereby preventing the separation of skin cells and the entry of pathogens. ExhC is of clinical importance since in addition to causing exfoliation in pigs and mice, it induces necrosis in multiple mammalian cell lines, a property not observed for other ETs. Previous experiments have implicated the ExhC79-128 fragment in causing necrosis. Site-directed mutagenesis of specific residues within this fragment were studied and led to the design of an ExhC variant containing four-point mutations (ExhCmut4) lacking necrotic potential but retaining nearly wild-type (wt) levels of enzymatic activity. Moreover, the determination of the ExhCwt and ExhCmut4 crystal structures identified the conformation in the necrosis-linked region. These results constitute an important step toward the understanding of the mechanisms underlying the necrotic and epidermolytic activity of ExhC.


Assuntos
Aminoácidos , Exfoliatinas , Animais , Suínos , Camundongos , Aminoácidos/metabolismo , Exfoliatinas/genética , Exfoliatinas/metabolismo , Exfoliatinas/farmacologia , Staphylococcus , Necrose , Mamíferos/metabolismo
2.
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.

3.
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
4.
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
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.
Med Microbiol Immunol ; 212(3): 193-201, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37029306

RESUMO

PURPOSE: Aedes aegypti mosquito-borne diseases have a significant impact on public health in Brazil. In this study, we investigated the presence of the Zika virus (ZIKV) and dengue virus (DENV) in serum and urine samples from symptomatic participants who attended an Emergency Care Unit located in a city in the northwestern region of São Paulo between February 2018 and April 2019. METHODS: Serum and urine samples were collected from participants suspected of having arbovirus infection. After the extraction of viral RNA, viral detection was performed by real-time quantitative reverse transcription polymerase chain reaction (RT-qPCR) (One-Step RT-qPCR). RESULTS: A total of 305 participants participated in this study. A total of 283 blood and 270 urine samples were collected. Of 305 patients, 36.4% (111/305) were positive for ZIKV, 43.3% (132/305) for DENV2, and 0.3% (1/305) for DENV1. Coinfection with ZIKV/DENV2 was observed in 13.1% of participants. If only serum samples were used, ZIKV detection would have decreased to 23.3% (71/305). Of all the participants included in the study, only one was suspected of having ZIKV infection based on clinical diagnosis, and the remaining participants were suspected of having DENV. CONCLUSION: By testing serum and urine samples, we increased the detection of both viruses and detected considerable levels of ZIKV and DENV-2 coinfection when compared to other studies. Additionally, we detected an unnoticed ZIKV outbreak in the city. These findings highlight the importance of the molecular diagnosis of arboviruses to aid public health surveillance and management strategies.


Assuntos
Febre de Chikungunya , Vírus Chikungunya , Coinfecção , Vírus da Dengue , Dengue , Infecção por Zika virus , Zika virus , Animais , Humanos , Infecção por Zika virus/diagnóstico , Infecção por Zika virus/epidemiologia , Dengue/diagnóstico , Dengue/epidemiologia , Vírus da Dengue/genética , Coinfecção/diagnóstico , Coinfecção/epidemiologia , Brasil/epidemiologia , Febre de Chikungunya/diagnóstico , Febre de Chikungunya/epidemiologia , Vírus Chikungunya/genética
7.
PLoS One ; 18(4): e0284296, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37053156

RESUMO

Condyloma acuminata (CA) is a benign proliferative disease mainly affecting in non-keratinized epithelia. Most cases of CA are caused by low-risk human papillomavirus (HPV), mainly HPV 6 and 11. The aim of the current study was to highlight the candidate genes and pathways associated with immune alterations in individuals who did not spontaneously eliminate the virus and, thus, develop genital warts. Paraffin-embedded condyloma samples (n = 56) were analyzed by immunohistochemistry using antibodies against CD1a, FOXP3, CD3, CD4, CD8, and IFN-γ. The immunomarkers were chosen based on the evaluation of the innate and adaptive immune pathways using qPCR analysis of 92 immune-related genes, applying a TaqMan Array Immune Response assay in HPV 6 or HPV 11 positive samples (n = 27). Gene expression analysis revealed 31 differentially expressed genes in CA lesions. Gene expression validation revealed upregulation of GZMB, IFNG, IL12B, and IL8 and downregulation of NFATC4 and IL7 in CA samples. Immunohistochemical analysis showed increased FOXP3, IFN-γ, CD1a, and CD4 expression in CA than in the control tissue samples. In contrast, CD3 and CD8 expression was decreased in CA lesion samples. Increased levels of pro-inflammatory cytokines in HPV-positive patients compared with HPV-negative patients seem to reflect the elevated immunogenicity of HPV-positive CA lesions. Host defense against HPV begins during the early stages of the innate immune response and is followed by activation of T lymphocytes, which are mainly represented by CD4+ and regulatory T cells. The low CD8+ T cell count in CA may contribute to this recurrent behavior. Additional studies are needed to elucidate the mechanism of host defense against HPV infection in CA.


Assuntos
Condiloma Acuminado , Infecções por Papillomavirus , Humanos , Infecções por Papillomavirus/genética , Condiloma Acuminado/genética , Condiloma Acuminado/patologia , Citocinas , Imunidade , Fatores de Transcrição Forkhead/genética , Papillomaviridae/genética
8.
Cell Biol Int ; 47(6): 1136-1146, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36906806

RESUMO

Inflammation in the established tumor microenvironment (TME) is often associated with a poor prognosis of breast cancer. Bisphenol A (BPA) is an endocrine-disrupting chemical that acts as inflammatory promoter and tumoral facilitator in mammary tissue. Previous studies demonstrated the onset of mammary carcinogenesis at aging when BPA exposure occurred in windows of development/susceptibility. We aim to investigate the inflammatory repercussions of BPA in TME in mammary gland (MG) during neoplastic development in aging. Female Mongolian gerbils were exposed to low (50 µg/kg) or high BPA (5000 µg/kg) doses during pregnancy and lactation. They were euthanized at 18 months of age (aging) and the MG were collected for inflammatory markers and histopathological analysis. Contrarily to control MG, BPA induced carcinogenic development mediated by COX-2 and p-STAT3 expression. BPA was also able to promote macrophage and mast cell (MC) polarization in tumoral phenotype, evidenced by pathways for recruitment and activation of these inflammatory cells and tissue invasiveness triggered by tumor necrosis factor-alpha and transforming growth factor-beta 1 (TGF-ß1). Increase of tumor-associated macrophages, M1 (CD68 + iNOS+) and M2 (CD163+) expressing pro-tumoral mediators and metalloproteases was observed; this aspect greatly contributed to stromal remodeling and invasion of neoplastic cells. In addition, the MC population drastically increased in BPA-exposed MG. Tryptase-positive MCs increased in disrupted MG and expressed TGF-ß1, contributing to EMT process during carcinogenesis mediated by BPA. BPA exposure interfered in inflammatory response by releasing and enhancing the expression of mediators that contribute to tumor growth and recruitment of inflammatory cells that promote a malignant profile.


Assuntos
Fator de Crescimento Transformador beta1 , Microambiente Tumoral , Gravidez , Feminino , Humanos , Compostos Benzidrílicos , Carcinogênese , Fenótipo
9.
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
10.
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
11.
Braz J Microbiol ; 53(3): 1279-1287, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35460509

RESUMO

Sexual transmission of Zika virus (ZIKV), an important arbovirus, and the virus persistence in semen raise several questions about how and where it circulates in the male reproductive system (MRS). Several studies reported detection of the virus in testes, epididymis, and prostate at 5 days post-infection (dpi) or more in animal models. In the present study, we investigated the interactions of ZIKV with mouse MRS using the AG129 strain, a ZIKV permissive immunodeficient mouse strain, at two dpi. Viral RNA was detected in blood, testes, epididymis, and prostatic complexes (prostate and seminal vesicles). Immunohistochemical (IHC) analyses, based on the envelope protein, showed an early infection in organs of MRS since ZIKV positive antigens were detected in cells within or surrounding blood vessels, Sertoli, and germ cells in testes and epithelial cells in epididymis and prostate. Positive antigens for NS5 protein, the virus RNA-dependent RNA polymerase, were also detected by IHC in these organs and circulating leukocytes, suggesting that the virus replicates in these sites as early as 2 days post-infection. Analysis of the early stages of ZIKV infection in MRS may improve the current knowledge about this issue and contribute to the development of therapies directed to the infection at this site.


Assuntos
Infecção por Zika virus , Zika virus , Animais , Genitália Masculina , Masculino , Camundongos , RNA Viral/genética , Sêmen , Zika virus/genética
12.
Cureus ; 14(2): e21961, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35282509

RESUMO

Condyloma acuminatum is a common clinical outcome of human papillomavirus (HPV) in men. A prospective investigation was performed of the clinical and molecular profile of 122 patients with condyloma acuminatum treated by the Brazilian public healthcare system. The patients were evaluated clinically. The fragments were submitted to molecular analysis for the identification of HPV genotypes. A total of 104 (85.2%) patients presented multiple warts and 18 (14.8%) presented a single wart. The predominant location was the body of the penis (48.4% of cases of multiple warts and 7.4% of cases of single warts), and 49 (40.2%) cases were recurrences and 73 (59.8%) were initial occurrences. Regarding sexual activity, 56 patients (45.9%) had multiple partners and 65 (53.3%) had a single partner. The most frequent genotype was HPV6 (70%). In conclusion, the most frequent anatomic location of condyloma acuminatum was the body of the penis in the present sample. The present findings suggest that the natural history of infection by HPV is not yet completely known and that greater care is needed to ensure clinical safety in the follow-up of these patients due to the oncogenic potential.

13.
Infection ; 50(1): 149-156, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34327616

RESUMO

PURPOSE: Studies show that around 80% of Zika virus (ZIKV) infections are asymptomatic. The present study tested urine samples from volunteers, unsuspected of arboviral infection, which attended an emergency care unit (ECU) in Mirassol, Brazil, from March 2018 to April 2019. METHODS: The volunteers were divided into two groups. The first group was composed of outpatients who were not suspected to have an arbovirus infection. This first group was subdivided into two subgroups: outpatients with and without arbovirus-like symptoms. The second group consisted of companions of outpatients treated at the ECU. The second group was also subdivided into two subgroups: totally asymptomatic individuals and those who had arbovirus-like symptoms. RNA was extracted from urine samples, followed by RT-qPCR for ZIKV. RESULTS: We found that 11% (79/697) of the samples tested positive for ZIKV-RNA. Among the ZIKV-RNA-positive individuals, 16.5% (13/79) were companions, of which 61.5% (8/13) were totally asymptomatic and 38.5% (5/13) reported symptoms that could be suggestive of arbovirus infection. In addition, 83.5% (66/79) of the ZIKV-RNA-positive individuals were outpatients without a clinical diagnosis of arbovirus. Of these undiagnosed ZIKV-RNA-positive outpatients, 47% (31/66) had no arbovirus-related symptoms. CONCLUSION: Our study shows the effectiveness of urine as a non-invasive sample to detect the incidence of ZIKV infection. We also highlight the importance of ZIKV molecular diagnosis to aid public health surveillance and prevention of congenital Zika syndrome and other ZIKV-associated diseases.


Assuntos
Infecção por Zika virus , Zika virus , Brasil/epidemiologia , Humanos , Vigilância em Saúde Pública , Zika virus/genética , Infecção por Zika virus/diagnóstico , Infecção por Zika virus/epidemiologia
14.
Viruses ; 15(1)2022 12 29.
Artigo em Inglês | MEDLINE | ID: mdl-36680131

RESUMO

Ilheus fever is a mosquito-borne, poorly known tropical disease. We aimed to report the pooled rate of exposure to the Ilheus virus (ILHV) and clinical outcomes of infection to determine the epidemiological patterns of ILHV. We conducted a meta-analysis of 37 studies (n = 17,722 individuals) from Latin America. The common clinical characteristics of ILHV infection were fever (82.3%), headache (52.9%), and myalgia (52.9%). Encephalitis complicated the course of the infection in 29.4% cases. Monotypic serological reactions detected a pooled rate of exposure of 2% to ILHV (95% CI: 1-2). Studies were mainly conducted in Brazil, with a pooled proportion of ILHV positivity of 8% (95% CI: 3-14). Males (12%) had higher rates of seropositivity than females (7%) and had high chances of ILHV infection (OR: 1.7, 95% CI: 1.2-2.5). Seropositivity increased with age, from 2% (95% CI: 2-3) among people aged 0-14 years to 8% (95% CI: 6-10) among people aged 15-64 years. Our analysis indicated a low and relatively constant burden of ILHV in Latin America. More research is needed to evaluate and innovate serological assays for ILHV to better estimate the burden and dynamics of epidemiological changes in ILHV infection in different regions.


Assuntos
Culicidae , Flavivirus , Animais , Masculino , Feminino , Humanos , Recém-Nascido , Lactente , Pré-Escolar , Criança , Adolescente , Brasil/epidemiologia , Filogenia
15.
J Virus Erad ; 7(3): 100054, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34548928

RESUMO

New variants of SARS-CoV-2 Alpha (B.1.1.7); Beta (B.1.351) Gamma (P.1) and Delta (B.1.617.2) quickly spread in the UK, South Africa, Brazil and India, respectively. To address whether mutations in SARS-CoV-2 RBD spike protein could affect virus infectivity, peptides containing RBD amino acids mutations have been constructed and interacted with human ACE2 by computational methods. Our results suggest that mutations in RBD amino acids K417, E484, L452, T478 and N501 are expressively increasing the affinity of this protein with human angiotensin-converting enzyme 2 (ACE2), consequently, variants Alpha (B.1.1.7), Beta (B1.351), Gamma (P.1) and Delta (B.1.617.2) could be more infective in human cells compared with SARS-CoV-2 isolated in Wuhan-2019 and the Gamma and Delta variants could be the most infective among them.

16.
Environ Pollut ; 289: 117818, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34333265

RESUMO

Knowledge about how the COVID-19 pandemic can affect aquatic wildlife is still extremely limited, and no effect of SARS-CoV-2 or its structural constituents on invertebrate models has been reported so far. Thus, we investigated the presence of the 2019-new coronavirus in different urban wastewater samples and, later, evaluated the behavioral and biochemical effects of the exposure of Culex quinquefasciatus larvae to two SARS-CoV-2 spike protein peptides (PSPD-2002 and PSPD-2003) synthesized in our laboratory. Initially, our results show the contamination of wastewater by the new coronavirus, via RT-qPCR on the viral N1 gene. On the other hand, our study shows that short-term exposure (48 h) to a low concentration (40 µg/L) of the synthesized peptides induced changes in the locomotor and the olfactory-driven behavior of the C. quinquefascitus larvae, which were associated with increased production of ROS and AChE activity (cholinesterase effect). To our knowledge, this is the first study that reports the indirect effects of the COVID-19 pandemic on the larval phase of a freshwater invertebrate species. The results raise concerns at the ecological level where the observed biological effects may lead to drastic consequences.


Assuntos
COVID-19 , Culicidae , Animais , Biota , Humanos , Larva , Pandemias , Peptídeos , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus
17.
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
18.
Arch Virol ; 166(6): 1681-1689, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33847814

RESUMO

Infection with distinct Zika virus (ZIKV) strains in in vitro and in vivo models has demonstrated that the host's response to infection is strain-dependent. There has been no analysis of the impact of infection with different ZIKV strains on miRNA expression in human cells. We investigated miRNA expression in PNT1A cells upon infection with an African ZIKV strain (MR766) and a Brazilian ZIKV strain (ZIKVBR) using PCR array. Sixteen miRNAs were modulated in PNT1A cells: six miRNAs were modulated by both strains, while a set of ten miRNAs were modulated exclusively by ZIKVBR infection. In silico analysis showed that nine significant KEGG pathways and eight significant GO terms were predicted to be enriched upon ZIKVBR infection, and these pathways were related to cancer, environmental information processing, metabolism, and extracellular matrix. Differential modulation of miRNA expression suggests that distinct strains of ZIKV can differentially modulate the host response through the action of miRNAs.


Assuntos
Regulação da Expressão Gênica/imunologia , MicroRNAs/metabolismo , Zika virus/classificação , Animais , Chlorocebus aethiops , Células Epiteliais/metabolismo , Células Epiteliais/virologia , Redes Reguladoras de Genes , Humanos , MicroRNAs/genética , Células Vero
19.
J Photochem Photobiol B ; 218: 112181, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33845338

RESUMO

Breast cancer is the most common neoplasm among women but thanks to innovative therapies, patients' prognosis has considerably improved. In this aspect, nanotechnology has been applied for cancer therapy aiming to reduce its usual side effects. In this study we aimed to evaluate the effects of nanoemulsions containing photosensitizer and chemotherapeutic agents associated with photodynamic therapy in a breast cancer in vivo model. Our results showed that synergistic treatments in which chloroaluminum phthalocyanine (NE-Pc) administered together with Doxorubicin (Dox) in the presence of laser irradiation (NE-PcDoxo + PDT) led to a reduction of 4 T1 induced breast cancer in mice, decline of tumor VEGF expression, increase in Caspase-3 expression, tissue necrosis and massive decrease in proliferative cells, as shown by Ki67 immunostaining. Furthermore, this associated treatment induced overexpression of apoptotic genes ABL1, CD70, CRADD, FASL, and NME5 and a reduction in expression of anticancer drug target genes CDK2, ERBB2, FIGF, IGF2, PARP4 and PGR. These results validate this treatment as a promising alternative to improve the currently applied anticancer strategies.


Assuntos
Antineoplásicos/química , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/radioterapia , Doxorrubicina/química , Indóis/química , Nanocápsulas/química , Compostos Organometálicos/química , Fármacos Fotossensibilizantes/química , Animais , Antineoplásicos/farmacologia , Caspase 3/genética , Caspase 3/metabolismo , Quinase 2 Dependente de Ciclina/genética , Quinase 2 Dependente de Ciclina/metabolismo , Doxorrubicina/farmacologia , Descoberta de Drogas , Quimioterapia Combinada , Emulsões/química , Feminino , Humanos , Indóis/farmacologia , Camundongos , Camundongos Endogâmicos BALB C , Neoplasias Experimentais , Compostos Organometálicos/farmacologia , Fotoquimioterapia , Fármacos Fotossensibilizantes/farmacologia , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo
20.
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
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...