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1.
Trop Anim Health Prod ; 56(2): 101, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38478351

RESUMO

The aim of the present study was to analyze the effects of visual morphological classification based on body structure, maturity, and musculosity on the morphometry of the reproduction system and productive parameters of beef heifers. The study was conducted for 84 days, during winter season in Brazil. Thirty non-pregnant Nellore heifers, with an average body weight 338 kg and average age 18 months, were used for the study. The heifers were housed in collective pens and fed corn silage (70%) and concentrate (30%) twice a day. All heifers were weighed weekly without prior fasting. Morphological evaluation of body structure, maturity, and musculosity was conducted in the third-middle of the experimental period by a trained evaluator, adopting a comparative methodology of visual evaluation on a scale from 1 to 6, and the heifers were classified according to the visual assessment. The effects of visual classification, time, and interactions were analyzed, considering significant effects was detected (p < 0.05). The significant (p < 0.05) results obtained were compared using Tukey test. Morphological classification did not influence the morphometry of the reproductive system or implied on time interactions. Body structure, maturity, and musculosity had no effect on dry matter intake, body weight gain, feed efficiency, and carcass dressing. However, body weight and feed efficiency were influenced by the experimental time. For both variables, significant variations were detected after 63 days of finishing in the feedlot (p < 0.001), indicating that maximum productive efficiency of feedlot-finished Nellore beef heifers was achieved at a mean body weight of 424 kg.


Assuntos
Ração Animal , Dieta , Bovinos , Animais , Feminino , Dieta/veterinária , Ração Animal/análise , Silagem , Peso Corporal , Genitália
2.
J Environ Sci Health B ; 59(4): 142-151, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38343082

RESUMO

Fungicides are specifically used for controlling fungal infections. Strobilurins, a class of fungicides originating from the mushroom Strobilurus tenacellus, act on the fungal mitochondrial respiratory chain, interrupting the ATP cycle and causing oxidative stress. Although strobilurins are little soluble in water, they have been detected in water samples (such as rainwater and drinking water), indoor dust, and sediments, and they can bioaccumulate in aquatic organisms. Strobilurins are usually absorbed orally and are mainly eliminated via the bile/fecal route and urine, but information about their metabolites is lacking. Strobilurins have low mammalian toxicity; however, they exert severe toxic effects on aquatic organisms. Mitochondrial dysfunction and oxidative stress are the main mechanisms related to the genotoxic damage elicited by toxic compounds, such as strobilurins. These mechanisms alter genes and cause other dysfunctions, including hormonal, cardiac, neurological, and immunological impairment. Despite limitations, we have been able to compile literature information about strobilurins. Many studies have dealt with their toxic effects, but further investigations are needed to clarify their cellular and underlying mechanisms, which will help to find ways to minimize the harmful effects of these compounds.


Assuntos
Fungicidas Industriais , Animais , Humanos , Estrobilurinas/toxicidade , Fungicidas Industriais/toxicidade , Fungicidas Industriais/análise , Estresse Oxidativo , Saúde Ambiental , Água , Mamíferos
3.
Sci Total Environ ; 916: 170012, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38246377

RESUMO

The search for new methods in the toxicology field has increased the use of early life stages of zebrafish (Danio rerio) as a versatile organism model. Here, we use early stages of zebrafish to evaluate glyphosate as pure active ingredient and within a commercial formulation in terms of oxidative stress. Biomarkers involved in the oxidative status were evaluated along with other markers of neurotoxicity, genotoxicity, cytotoxicity, energy balance and motor performance, and the selected tools were evaluated by its sensitivity in determining early-warning events. Zebrafish embryos exposed to glyphosate active ingredient and glyphosate-based formulation were under oxidative stress, but only the commercial formulation delayed the embryogenesis, affected the cholinergic neurotransmission and induced DNA damage. Both altered the motor performance of larvae at very low concentrations, becoming larvae hypoactive. The energy balance was also impaired, as embryos under oxidative stress had lower lipids reserves. Although data suggest that glyphosate-based formulation has higher toxicity than the active ingredient itself, the most sensitive biomarkers detected early-warning effects at very low concentrations of the active ingredient. Biochemical biomarkers of defense system and oxidative damage were the most sensitive tools, detecting pro-oxidant responses at very low concentrations, along with markers of motor performance that showed high sensitivity and high throughput, suitable for detecting early effects linked to neurotoxicity. Alterations on morphology during embryogenesis showed the lowest sensitivity, thus morphological alterations appeared after several alterations at biochemical levels. Tools evaluating DNA damage and cell proliferation showed mid-sensitivity, but low throughput, thus they could be used as complementary markers.


Assuntos
Glifosato , Herbicidas , Animais , Peixe-Zebra/fisiologia , Glicina/toxicidade , Herbicidas/toxicidade , Estresse Oxidativo , Larva
4.
Sci Total Environ ; 912: 168741, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38040350

RESUMO

Benzotriazoles are heterocyclic compounds typically presenting a benzene ring fused with a triazole molecule. The industry uses these compounds as anti-corrosion agents and recently, they have been employed in the pharmaceutical industry and in detergent formulations. Benzotriazoles persist in the environment, and water treatment plants cannot degrade them completely. Consequently, these compounds have been detected in rivers, lakes, and drinking water, which makes assessing their safety for the human and aquatic animal populations crucial. Here, we have evaluated and compared how exposure to 1H-benzotriazole or 5-chloro-benzotriazole affect the zebrafish embryo-larval stages. We have determined the acute toxicity, morphometric alterations, and acetylcholinesterase activity on zebrafish embryos, as well as behavioral endpoints using the tail coiling assay. The estimated LC50 of 5-chloro-benzotriazole was 19 mg/L, whereas 1H-benzotriazole caused no mortality. The zebrafish embryos exposed to 20 and 25 mg/L 5-chloro-benzotriazole had decreased hatching rate and exhibited pericardial and yolk sac edemas. Furthermore, the embryo length and eye area were decreased, in contrast with an increased yolk sac after exposure to 20 mg/L 5-chloro-benzotriazole. In turn, 1H-benzotriazole also decreased the eye area of zebrafish embryos, but no other significant morphological alterations were observed. The tail coiling assay showed that the zebrafish embryos increased the percentage of time moving and the number of embryonic movements per minute after exposure to 1H-benzotriazole (15 mg/L) or 5-chloro-benzotriazole (20 and 25 mg/L), indicating that these compounds were potentially neurotoxic. However, acetylcholinesterase activity was not significantly altered in embryos exposed to 1H-benzotriazole, but significantly decreased when exposed to 0.05 mg/L 5-chloro benzotriazole confirming its neurotoxicity at a much lower concentration. Our findings showed that 5-chloro-benzotriazole seems to induce more harmful alterations to zebrafish embryos than 1H-benzotriazole. Nevertheless, 1H-benzotriazole seems to induce a direct effect on eye development for concentrations lower than the ones of 5-chloro-benzotriazole affecting zebrafish embryos.


Assuntos
Poluentes Químicos da Água , Peixe-Zebra , Animais , Humanos , Acetilcolinesterase , Triazóis/toxicidade , Dose Letal Mediana , Embrião não Mamífero , Poluentes Químicos da Água/toxicidade
5.
Artigo em Inglês | MEDLINE | ID: mdl-37998288

RESUMO

(1) Background: Some older people hospitalized with COVID-19 have experienced reduced ambulation capacity. However, the prevalence of the impairment of ambulation capacity still needs to be established. Objective: To estimate the prevalence of, and identify the risk factors associated with, the impairment of ambulation capacity at the point of hospital discharge for older people with COVID-19. (2) Methods: A retrospective cohort study. Included are those with an age > 60 years, of either sex, hospitalized due to COVID-19. Clinical data was collected from patients' medical records. Ambulation capacity prior to COVID-19 infection was assessed through the patients' reports from their relatives. Multiple logistic regressions were performed to identify the risk factors associated with the impairment of ambulation at hospital discharge. (3) Results: Data for 429 older people hospitalized with COVID-19 were randomly collected from the medical records. Among the 56.4% who were discharged, 57.9% had reduced ambulation capacity. Factors associated with reduced ambulation capacity at discharge were a hospital stay longer than 20 days (Odds Ratio (OR): 3.5) and dependent ambulation capacity prior to COVID-19 (Odds Ratio (OR): 11.3). (4) Conclusion: More than half of the older people who survived following hospitalization due to COVID-19 had reduced ambulation capacity at hospital discharge. Impaired ambulation prior to the infection and a longer hospital stay were risks factors for reduced ambulation capacity.


Assuntos
COVID-19 , Humanos , Idoso , Pessoa de Meia-Idade , Estudos Retrospectivos , COVID-19/epidemiologia , Hospitalização , Caminhada , Fatores de Risco
6.
Commun Biol ; 6(1): 1058, 2023 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-37853179

RESUMO

Several drug screening campaigns identified Calpeptin as a drug candidate against SARS-CoV-2. Initially reported to target the viral main protease (Mpro), its moderate activity in Mpro inhibition assays hints at a second target. Indeed, we show that Calpeptin is an extremely potent cysteine cathepsin inhibitor, a finding additionally supported by X-ray crystallography. Cell infection assays proved Calpeptin's efficacy against SARS-CoV-2. Treatment of SARS-CoV-2-infected Golden Syrian hamsters with sulfonated Calpeptin at a dose of 1 mg/kg body weight reduces the viral load in the trachea. Despite a higher risk of side effects, an intrinsic advantage in targeting host proteins is their mutational stability in contrast to highly mutable viral targets. Here we show that the inhibition of cathepsins, a protein family of the host organism, by calpeptin is a promising approach for the treatment of SARS-CoV-2 and potentially other viral infections.


Assuntos
COVID-19 , Humanos , SARS-CoV-2/metabolismo , Catepsinas , Antivirais/farmacologia , Antivirais/uso terapêutico , Antivirais/química , Inibidores de Proteases/farmacologia , Cisteína Endopeptidases/metabolismo
7.
Toxicol In Vitro ; 91: 105628, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37302535

RESUMO

Retene is a polycyclic aromatic hydrocarbon (PAH) emitted mainly by biomass combustion, and despite its ubiquity in atmospheric particulate matter (PM), studies concerning its potential hazard to human health are still incipient. In this study, the cytotoxicity and genotoxicity of retene were investigated in human HepG2 liver cells. Our data showed that retene had minimal effect on cell viability, but induced DNA strand breaks, micronuclei formation, and reactive oxygen species (ROS) formation in a dose- and time-dependent manner. Stronger effects were observed at earlier time points than at longer, indicating transient genotoxicity. Retene activated phosphorylation of Checkpoint kinase 1 (Chk1), an indicator of replication stress and chromosomal instability, which was in accordance with increased formation of micronuclei. A protective effect of the antioxidant N-acetylcysteine (NAC) towards ROS generation and DNA damage signaling was observed, suggesting oxidative stress as a key mechanism of the observed genotoxic effects of retene in HepG2 cells. Altogether our results suggest that retene may contribute to the harmful effects caused by biomass burning PM and represent a potential hazard to human health.


Assuntos
Dano ao DNA , Material Particulado , Humanos , Espécies Reativas de Oxigênio , Células Hep G2 , Estresse Oxidativo , Fígado
8.
Viruses ; 15(4)2023 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-37112979

RESUMO

Since December 2019, the world has been experiencing the COVID-19 pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), and we now face the emergence of several variants. We aimed to assess the differences between the wild-type (Wt) (Wuhan) strain and the P.1 (Gamma) and Delta variants using infected K18-hACE2 mice. The clinical manifestations, behavior, virus load, pulmonary capacity, and histopathological alterations were analyzed. The P.1-infected mice showed weight loss and more severe clinical manifestations of COVID-19 than the Wt and Delta-infected mice. The respiratory capacity was reduced in the P.1-infected mice compared to the other groups. Pulmonary histological findings demonstrated that a more aggressive disease was generated by the P.1 and Delta variants compared to the Wt strain of the virus. The quantification of the SARS-CoV-2 viral copies varied greatly among the infected mice although it was higher in P.1-infected mice on the day of death. Our data revealed that K18-hACE2 mice infected with the P.1 variant develop a more severe infectious disease than those infected with the other variants, despite the significant heterogeneity among the mice.


Assuntos
COVID-19 , SARS-CoV-2 , Animais , Humanos , Camundongos , Modelos Animais de Doenças , Camundongos Transgênicos , Pandemias , SARS-CoV-2/genética , Virulência
9.
Pathogens ; 12(3)2023 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-36986360

RESUMO

The present case study describes the dermatological manifestations of COVID-19 in a patient with genetic thrombophilia (MTHFR-C677T mutation) and the identification of a SARS-CoV-2 variant of interest (VOI). A female patient, 47 years old, unvaccinated, with thrombophilia, was diagnosed with COVID-19. She presented with urticarial and maculopapular eruptions from the seventh day of symptoms, which progressed to multiple lesions with dark centers (D-dimer value > 1450 ng/mL). The dermatological manifestations disappeared after 30 days, corroborating the reduction in D-dimer levels. Viral genome sequencing revealed infection by the VOI Zeta (P.2). Antibody testing, performed 30 days after the onset of symptoms, detected only IgG. The virus neutralization test showed the highest neutralizing titer for a P.2 strain, validating the genotypic identification. Lesions were suggested to be due to infection in skin cells causing a direct cytopathic effect or release of pro-inflammatory cytokines triggering erythematous and urticarial eruptions. In addition, vascular complications are also proposed to be due to the MTHFR mutation and increased D-dimer values. This case report is an alert about COVID-19 in patients with pre-existing vascular diseases, especially in unvaccinated patients, by VOI.

10.
Sci Rep ; 13(1): 898, 2023 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-36650374

RESUMO

Since the molecular mechanisms determining COVID-19 severity are not yet well understood, there is a demand for biomarkers derived from comparative transcriptome analyses of mild and severe cases, combined with patients' clinico-demographic and laboratory data. Here the transcriptomic response of human leukocytes to SARS-CoV-2 infection was investigated by focusing on the differences between mild and severe cases and between age subgroups (younger and older adults). Three transcriptional modules correlated with these traits were functionally characterized, as well as 23 differentially expressed genes (DEGs) associated to disease severity. One module, correlated with severe cases and older patients, had an overrepresentation of genes involved in innate immune response and in neutrophil activation, whereas two other modules, correlated with disease severity and younger patients, harbored genes involved in the innate immune response to viral infections, and in the regulation of this response. This transcriptomic mechanism could be related to the better outcome observed in younger COVID-19 patients. The DEGs, all hyper-expressed in the group of severe cases, were mostly involved in neutrophil activation and in the p53 pathway, therefore related to inflammation and lymphopenia. These biomarkers may be useful for getting a better stratification of risk factors in COVID-19.


Assuntos
Fatores Etários , COVID-19 , Gravidade do Paciente , Humanos , Biomarcadores/metabolismo , COVID-19/genética , Leucócitos/metabolismo , SARS-CoV-2/metabolismo , Transcriptoma
11.
Physiother Res Int ; 28(2): e1983, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36377222

RESUMO

BACKGROUND AND OBJECTIVES: Hospitalization by Covid-19 can cause persistent functional consequences after hospital discharge due to direct and indirect effects of SARS-COV-2 in several organs and systems of the body added to post-intensive care syndrome and prolonged bed rest. These impacts can lead to dependency in activities of daily living, mainly in older people due to aging process and functional decline. This study aimed to compare the effects of hospitalization by Covid-19 on functional capacity of adults and older people and to identify its associated factors. METHODS: Cross-sectional observational study of 159 survivors of hospitalization by Covid-19 after 1 month from discharge at Hospital das Clínicas of the University of São Paulo, divided into groups: adults (aged < 60 years) and older people (aged ≥ 60 years). Those who did not accept to participate, without availability or without ability to understand the questionnaires were excluded. Functional capacity was assessed by the Barthel Index and patients were classified according to their scores. Data analysis was performed in JASP Statistics program and the sample was compared between the age groups. Wilcoxon test was applied to compare before and after periods, Mann-Whitney test was used for between groups comparison. We adopted alpha = 0.05. RESULTS: The total Barthel Index median score was lower 1 month after hospital discharge than in the pre-Covid-19 period. Older people had worse functional status than adults before and also showed greater impairment after hospital discharge. Both groups showed lower Barthel Index classification than before, and older people presented more functional dependence than adults in both periods. Age, sarcopenia and frailty were associated factors. DISCUSSION: Hospitalization by Covid-19 impacts functional capacity after 1 month from discharge, especially in older people. Age, sarcopenia and frailty are associated factors. These results suggest need for care and rehabilitation of Covid-19 survivors.


Assuntos
COVID-19 , Fragilidade , Sarcopenia , Humanos , Adulto , Idoso , Atividades Cotidianas , Estudos Transversais , SARS-CoV-2 , Hospitalização
12.
Artigo em Inglês | MEDLINE | ID: mdl-36429748

RESUMO

The present study aimed to assess the prevalence and associated factors of stress and anxiety symptoms among dentists during the COVID-19 pandemic in the state of São Paulo, Brazil. A structured questionnaire was sent electronically to 93,280 dentists with active registration in the Dental Council of São Paulo, Brazil, enquiring about information regarding the first-wave peak period in Brazil. Descriptive analyses of background characteristics, perceptions of preparedness, and psychological impact were calculated. Multiple logistic regression analysis was performed, and independent variables that showed p < 0.20 were used in the adjusted logistic regression model to compare the psychological impact on dental professionals. Among the 2113 respondents, female participants had 63% lower chance of reporting anxiety than males. Older dentists had a lower likelihood of reporting anxiety compared to 21-30-year-old dentists (p ≤ 0.05). Dentists working in the public health service were 1.78 times more likely to report anxiety than those who worked in private practice. Finally, dentists in the COVID-19 high-risk group and those with a family or team member with a positive COVID-19 diagnosis were more likely to have anxiety. This study can help dental and other healthcare professionals to better understand the consequences of COVID-19 in terms of mental health.


Assuntos
COVID-19 , Feminino , Humanos , Masculino , Brasil/epidemiologia , COVID-19/epidemiologia , Teste para COVID-19 , Odontólogos/psicologia , América Latina , Pandemias
13.
Regul Toxicol Pharmacol ; 136: 105288, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36384172

RESUMO

This paper describes DARAN (Defined Approach for Risk Assessment of New Nitrosamines), an new defined approach that uses lines of reasoning based on structure-activity relationship (SAR) patterns and Read-Across (RAx) to set transparent and acceptable limits for new N-nitrosamines for which no toxicological data exist. We selected the compound 1-methyl-4-nitrosopiperazine (MeNP) as a target to calculate a new acceptable limit on the basis of a more transparent and scientifically reasoned RAx. We used publicly available databases and datasets to retrieve experimental in vitro mutagenicity and in vivo carcinogenicity data for N-nitrosopiperazine compounds and to form the chemical category for an RAx. We carried out SAR analyses to try to understand patterns and to obtain interpretable inferences of variation in carcinogenic potency among the N-nitrosopiperazines compounds and their differences with the potent nitrosamines NDMA (N-nitrosodimethylamine) and NDEA (N-nitrosodiethylamine). To estimate an acceptable limit for the target MeNP, we used the scientifically based hypotheses and the evidence lines of about the influence of structural attributes for a robust RAx. On the basis of the criteria proposed in the Assessment Report EMA/369136/20202 and by using the SAR hypotheses obtained by the analysis, we obtained a robust RAx, scientifically supported assumptions, which resulted in TD50 values predicted from the closest structurally related compounds and a worst-case approach.


Assuntos
Nitrosaminas , Nitrosaminas/toxicidade , Nitrosaminas/análise , Dimetilnitrosamina/análise , Carcinógenos , Relação Estrutura-Atividade , Dietilnitrosamina
14.
Front Microbiol ; 13: 1040093, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36386719

RESUMO

Hemorrhagic fever viruses (HFVs) pose a threat to global public health owing to the emergence and re-emergence of highly fatal diseases. Viral hemorrhagic fevers (VHFs) caused by these viruses are mostly characterized by an acute febrile syndrome with coagulation abnormalities and generalized hemorrhage that may lead to life-threatening organ dysfunction. Currently, the events underlying the viral pathogenicity associated with multiple organ dysfunction syndrome still underexplored. In this minireview, we address the current knowledge of the mechanisms underlying VHFs pathogenesis and discuss the available development of preventive and therapeutic options to treat these infections. Furthermore, we discuss the potential of HFVs to cause worldwide emergencies along with factors that favor their spread beyond their original niches.

15.
Front Cell Infect Microbiol ; 12: 900608, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35873163

RESUMO

Zika is a vector-borne disease caused by an arbovirus (ZIKV) and overwhelmingly transmitted by Ae. aegypti. This disease is linked to adverse fetal outcomes, mostly microcephaly in newborns, and other clinical aspects such as acute febrile illness and neurologic complications, for example, Guillain-Barré syndrome. One of the most promising strategies to mitigate arbovirus transmission involves releasing Ae. aegypti mosquitoes carrying the maternally inherited endosymbiont bacteria Wolbachia pipientis. The presence of Wolbachia is associated with a reduced susceptibility to arboviruses and a fitness cost in mosquito life-history traits such as fecundity and fertility. However, the mechanisms by which Wolbachia influences metabolic pathways leading to differences in egg production remains poorly known. To investigate the impact of coinfections on the reproductive tract of the mosquito, we applied an isobaric labeling-based quantitative proteomic strategy to investigate the influence of Wolbachia wMel and ZIKV infection in Ae. aegypti ovaries. To the best of our knowledge, this is the most complete proteome of Ae. aegypti ovaries reported so far, with a total of 3913 proteins identified, were also able to quantify 1044 Wolbachia proteins in complex sample tissue of Ae. aegypti ovary. Furthermore, from a total of 480 mosquito proteins modulated in our study, we discuss proteins and pathways altered in Ae. aegypti during ZIKV infections, Wolbachia infections, coinfection Wolbachia/ZIKV, and compared with no infection, focusing on immune and reproductive aspects of Ae. aegypti. The modified aspects mainly were related to the immune priming enhancement by Wolbachia presence and the modulation of the Juvenile Hormone pathway caused by both microorganism's infection.


Assuntos
Aedes , Coinfecção , Wolbachia , Infecção por Zika virus , Zika virus , Aedes/microbiologia , Animais , Feminino , Humanos , Recém-Nascido , Mosquitos Vetores , Ovário , Proteômica
16.
Percept Mot Skills ; 129(5): 1362-1380, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35790415

RESUMO

Harmonious voluntary movements require efficiency in their planning and execution. Throughout middle childhood structural changes in the central nervous and musculoskeletal systems influence these processes and resultant motor behavior. In this study, we evaluated the characteristics of the motor planning and executing of aiming movements directed at targets located in different positions in space in children aged 7, 9, and 11 years. We divided 43 right-handed children, into three age groups and instructed them to perform aiming movements directed at targets using a stylus on a digital tablet. The children performed the movement with their dominant upper limbs from a starting point towards targets positioned ipsilaterally or contralaterally to this dominant limb. We analyzed temporal and spatial variables of motor performance. Younger (7-year-old) children made more errors in the initial movement direction and more frequently corrected their movements during task execution when compared to 9- and 11-year-old children who did not differ from each other. All age groups were similar in movement accuracy and precision. Movements toward contralateral targets were slower and more accurate than movements toward ipsilateral targets for all groups. These results show that performing aiming movements develop with the onset of middle childhood.


Assuntos
Lateralidade Funcional , Desempenho Psicomotor , Criança , Lateralidade Funcional/fisiologia , Mãos/fisiologia , Humanos , Movimento/fisiologia , Desempenho Psicomotor/fisiologia , Extremidade Superior
17.
Sci Rep ; 12(1): 3890, 2022 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-35273234

RESUMO

The new outbreak of coronavirus disease 2019 (COVID-19) has infected and caused the death of millions of people worldwide. Intensive efforts are underway around the world to establish effective treatments. Immunoglobulin from immunized animals or plasma from convalescent patients might constitute a specific treatment to guarantee the neutralization of the virus in the early stages of infection, especially in patients with risk factors and a high probability of progressing to severe disease. Worldwide, a few clinical trials using anti-SARS-CoV-2 immunoglobulins from horses immunized with the entire spike protein or fragments of it in the treatment of patients with COVID-19 are underway. Here, we describe the development of an anti-SARS-CoV-2 equine F(ab')2 immunoglobulin using a newly developed SARS-CoV-2 viral antigen that was purified and inactivated by radiation. Cell-based and preclinical assays showed that the F(ab')2 immunoglobulin successfully neutralizes the virus, is safe in animal models, and reduces the severity of the disease in a hamster model of SARS-CoV-2 infection and disease.


Assuntos
COVID-19/terapia , Imunoglobulinas/uso terapêutico , Receptores Imunológicos/uso terapêutico , SARS-CoV-2/imunologia , Animais , Ensaio de Imunoadsorção Enzimática , Feminino , Cavalos/imunologia , Humanos , Imunoglobulinas/imunologia , Imunoglobulinas/isolamento & purificação , Masculino , Mesocricetus/imunologia , Plasmaferese/veterinária , Receptores Imunológicos/imunologia
19.
Int J Pediatr Otorhinolaryngol ; 153: 111013, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34974278

RESUMO

BACKGROUND: In children, an acute demyelinating disease may evolve as a multiphasic disease with multiple relapses, such as multiple sclerosis (MS) and neuromyelitis optica spectrum disorder (NMOSD). The Brainstem Auditory Evoked Potentials (BAEP) and Long-Latency Auditory Evoked Potentials (LLAEP) contribute to the identification of either retrocochlear changes or other central auditory nervous system (CANS) changes. OBJECTIVES: To characterize BAEP and LLAEP in children and adolescents with MS and NMOSD and verify the diagnostic values of these potentials in each of the demyelinating diseases. METHODS: The 40 participants were divided into two study groups (SG1 - MS, SG2 - NMOSD) and two comparison groups (CG1 and CG2), matched for age (9 years-17 years and 11 months) and sex. Electrophysiological hearing assessment was performed with BAEP and LLAEP. RESULTS: When SG1 and SG2 were compared with CG1 and CG2 regarding BAEP and LLAEP, both SG1 and SG2 presented a higher occurrence of changes. Also, individuals with MS had higher occurrences of BAEP changes, whereas individuals with NMOSD had a higher occurrence of LLAEP changes. CONCLUSIONS: BAEP and LLAEP in children and adolescents with MS or NMOSD showed higher latencies and lower amplitudes of some components when these individuals were compared with their peers. These procedures were highly accurate to identify demyelinating diseases. BAEP results were more abnormal in individuals with MS, while LLAEP was so with NMOSD. These findings indicate that the auditory evoked potentials are important instruments for the differential diagnosis of MS and NMOSD, and valuable to monitor disease evolution.


Assuntos
Esclerose Múltipla , Neuromielite Óptica , Adolescente , Criança , Diagnóstico Diferencial , Potenciais Evocados Auditivos , Potenciais Evocados Auditivos do Tronco Encefálico , Humanos , Esclerose Múltipla/diagnóstico , Neuromielite Óptica/diagnóstico
20.
Biomol NMR Assign ; 16(1): 31-35, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34817802

RESUMO

Zika virus (ZIKV) emerged as a global public health concern due to its relationship with severe neurological disorders. Non-structural (NS) proteins of ZIKV are essential for viral replication, regulatory function, and subversion of host responses. NS2B is a membrane protein responsible for the regulation of viral protease activity. This protein has transmembrane domains critical for the localization of viral protease to the endoplasmic reticulum membrane and a hydrophilic domain essential for folding, recruitment, and protease activity. Therefore, NS2B is considered a cofactor of viral protease which processes viral polyprotein and is essential for virus replication, making it an attractive antiviral drug target. Here, we report the backbone 1H, 15N, 13C resonance assignments of the full-length NS2B by high-resolution NMR. The backbone assignment will be necessary for determining the three-dimensional structure and backbone dynamics of NS2B, interaction mapping and screening potential of antiviral drugs against ZIKV and related pathogenic flaviviruses.


Assuntos
Proteínas não Estruturais Virais , Zika virus , Ressonância Magnética Nuclear Biomolecular , Proteínas não Estruturais Virais/química , Proteases Virais/química , Zika virus/química
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