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1.
Nat Commun ; 15(1): 4670, 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38821983

RESUMEN

The major ampullate Spidroin 1 (MaSp1) is the main protein of the dragline spider silk. The C-terminal (CT) domain of MaSp1 is crucial for the self-assembly into fibers but the details of how it contributes to the fiber formation remain unsolved. Here we exploit the fact that the CT domain can form silk-like fibers by itself to gain knowledge about this transition. Structural investigations of fibers from recombinantly produced CT domain from E. australis MaSp1 reveal an α-helix to ß-sheet transition upon fiber formation and highlight the helix No4 segment as most likely to initiate the structural conversion. This prediction is corroborated by the finding that a peptide corresponding to helix No4 has the ability of pH-induced conversion into ß-sheets and self-assembly into nanofibrils. Our results provide structural information about the CT domain in fiber form and clues about its role in triggering the structural conversion of spidroins during fiber assembly.


Asunto(s)
Fibroínas , Arañas , Fibroínas/química , Fibroínas/metabolismo , Animales , Arañas/metabolismo , Seda/química , Seda/metabolismo , Dominios Proteicos , Secuencia de Aminoácidos , Conformación Proteica en Lámina beta , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/genética , Concentración de Iones de Hidrógeno , Conformación Proteica en Hélice alfa , Estructura Secundaria de Proteína
2.
Nutrients ; 16(6)2024 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-38542678

RESUMEN

This study aimed to characterize the composition of lipids in the red blood cells (RBCs) of adolescent swimmers and correlate this lipidome with the aerobic performance of the athletes. Five experimental assessments were performed by 37 adolescent swimmers. During the first session, the athletes went to the laboratory facility for venous blood sampling. The critical velocity protocol was conducted over the 4 subsequent days to measure aerobic performance (CV), comprising maximal efforts over distances of 100, 200, 400, and 800 m in a swimming pool. RBCs were obtained and extracted for analysis using the liquid chromatography-high resolution mass spectrometry untargeted approach. A total of 2146 ions were detected in the RBCs, of which 119 were identified. The enrichment pathway analysis indicated intermediary lipids in the glycerophospholipid, glycerolipid, sphingolipid, linoleic acid, and alpha-linolenic metabolisms, as well as pentose and glucuronate interconversions. A significant impact of the intermediary lipids was observed for the glycerophospholipid metabolism, including phosphatidylethanolamine (PE), phosphatidylcholine (PC), 1-acyl-sn-glycero-3-phosphocholine, sn-glycerol 3-phosphate, and phosphatidic acid. Inverse and significant associations were observed for PE 18:2/18:3 (r = -0.39; p = 0.015), PC 18:3/20:0 (r = -0.33; p = 0.041), and phosphatidic acid 18:0/0:0 (r = -0.47; p = 0.003) with aerobic performance. Swimmers who exhibited higher levels of aerobic performance also had the lowest abundance of PE, PC, and phosphatidic acid.


Asunto(s)
Glicerofosfolípidos , Fosfatidilcolinas , Adolescente , Humanos , Ácidos Fosfatidicos , Glicerilfosforilcolina , Eritrocitos
3.
Protein J ; 43(2): 333-350, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38347326

RESUMEN

A novel trypsin inhibitor from Cajanus cajan (TIC) fresh leaves was partially purified by affinity chromatography. SDS-PAGE revealed one band with about 15 kDa with expressive trypsin inhibitor activity by zymography. TIC showed high affinity for trypsin (Ki = 1.617 µM) and was a competitive inhibitor for this serine protease. TIC activity was maintained after 24 h of treatment at 70 °C, after 1 h treatments with different pH values, and ß-mercaptoethanol increasing concentrations, and demonstrated expressive structural stability. However, the activity of TIC was affected in the presence of oxidizing agents. In order to study the effect of TIC on secreted serine proteases, as well as on the cell culture growth curve, SK-MEL-28 metastatic human melanoma cell line and CaCo-2 colon adenocarcinoma was grown in supplemented DMEM, and the extracellular fractions were submitted salting out and affinity chromatography to obtain new secreted serine proteases. TIC inhibited almost completely, 96 to 89%, the activity of these serine proteases and reduced the melanoma and colon adenocarcinoma cells growth of 48 and 77% respectively. Besides, it is the first time that a trypsin inhibitor was isolated and characterized from C. cajan leaves and cancer serine proteases were isolated and partial characterized from SK-MEL-28 and CaCo-2 cancer cell lines. Furthermore, TIC shown to be potent inhibitor of tumor protease affecting cell growth, and can be one potential drug candidate to be employed in chemotherapy of melanoma and colon adenocarcinoma.


Asunto(s)
Cajanus , Hojas de la Planta , Humanos , Cajanus/química , Hojas de la Planta/química , Células CACO-2 , Proliferación Celular/efectos de los fármacos , Línea Celular Tumoral , Inhibidores de Tripsina/farmacología , Inhibidores de Tripsina/química , Inhibidores de Tripsina/aislamiento & purificación , Proteínas de Plantas/farmacología , Proteínas de Plantas/química , Proteínas de Plantas/aislamiento & purificación , Serina Proteasas/química , Serina Proteasas/aislamiento & purificación , Serina Proteasas/metabolismo
4.
Artículo en Inglés | MEDLINE | ID: mdl-38334123

RESUMEN

Incorporating enzymes into nanostructured supercapacitor devices represents a groundbreaking advancement in energy storage. Enzyme catalysis using nanomaterials enhances performance, efficiency, and stability by facilitating precise charge transfer, while the nanostructure provides a high surface area and improved conductivity. This synergy yields eco-friendly, high-performance energy storage solutions crucial for diverse applications, from portable electronics to renewable energy systems. In this study, we harnessed the versatility of Langmuir-Blodgett films to create meticulously organized thin films with specific enzyme properties, coupled with carbon nanotubes, to develop biosupercapacitors. Langmuir monolayers were constructed with stearic acid, carbon nanotubes, and galactose oxidase. Following comprehensive characterization using tensiometric, rheological, morphological, and spectroscopic techniques, the monolayers were transferred to solid supports, yielding Langmuir-Blodgett films. These films exhibited superior performance, with persisting enzyme activity. However, increasing film thickness did not enhance enzymatic activity values, indicating a surface-driven process. Subsequently, we explored the electrochemical properties of the films, revealing stability compatible with supercapacitor applications. The introduction of carbon nanotubes demonstrated a higher capacitance, indicating the potential viability of the films for energy storage applications.

5.
Neuropeptides ; 103: 102390, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37984248

RESUMEN

Venom-derived peptides are important sources for the development of new therapeutic molecules, especially due to their broad pharmacological activity. Previously, our research group identified a novel natural peptide, named fraternine, with promising effects for the treatment of Parkinson's disease. In the present paper, we synthesized three peptides bioinspired in fraternine: fra-10, fra-14, and fra-24. They were tested in the 6-OHDA-induced model of parkinsonism, quantifying motor coordination, levels of TH+ neurons in the substantia nigra pars compacta (SN), and inflammation mediators TNF-α, IL-6, and IL-1ß in the cortex. Peptides fra-14 and fra-10 improved the motor coordination in relation to 6-OHDA lesioned animals. However, most of the peptides were toxic in the doses applied. All three peptides reduced the intensity of the lesion induced rotations in the apomorphine test. Fra-24 higher dose increased the number of TH+ neurons in SN and reduced the concentration of TNF-α in the cortex of 6-OHDA lesioned mice. Overall, only the peptide fra-24 presented a neuroprotection effect on dopaminergic neurons of SN and a reduction of cytokine TNF-α levels, making it worthy of consideration for the treatment of PD.


Asunto(s)
Enfermedad de Parkinson , Ratones , Animales , Enfermedad de Parkinson/tratamiento farmacológico , Oxidopamina , Factor de Necrosis Tumoral alfa , Sustancia Negra , Antiparkinsonianos/farmacología , Antiparkinsonianos/uso terapéutico , Neuronas Dopaminérgicas , Modelos Animales de Enfermedad
6.
Rev. biol. trop ; 71(1)dic. 2023.
Artículo en Inglés | SaludCR, LILACS | ID: biblio-1514963

RESUMEN

Introduction: The lack of knowledge on seed germination and seedling establishment is a main constraint for the restoration of degraded areas, including the tropical dry forest known as Caatinga. Objective: To assess reserve and secondary metabolite mobilization during seed germination and seedling establishment in Erythina velutina. Methods: We scarified, disinfected, imbibed, sown between towel paper, and incubated seeds under controlled conditions. We hydroponically cultivated seedlings in a greenhouse. We harvested cotyledons at seed imbibition, radicle protrusion, hypocotyl emergence, apical hook formation and expansion of cordiform leaves, first trifoliate leaf, and second trifoliate leaf. Results: Seeds contained approximately 20 % starch, 14.5 % storage proteins, 11.6 % neutral lipids, and 5.7 % non-reducing sugars on a dry weight basis. Soluble sugars were mainly consumed from hypocotyl emergence to apical hook formation, while major reserves were mobilized from apical hook formation to expansion of first trifoliate leaf. Enzymatic activity increased from mid to late seedling establishment, causing the mobilization of starch, oils, and proteins. Terpenoid-derivatives, flavonoids, phenolic acids, and alkaloids were detected. Flavonoids and phenolic acids were present at almost all stages and terpenoid-derivatives disappeared at expansion of cordiform leaves. Conclusion: Soluble sugars support early seedling growth, while starch, oils and proteins are simultaneously mobilized from mid to late establishment by amylases, lipases, and acid proteases. The cotyledons contain secondary metabolites, which may act in seedling defense. High content of reserves and presence of secondary metabolites in the cotyledons could enable E. velutina seedlings endure stress, validating their use in the restoration of degraded areas.


Introducción: La falta de conocimiento sobre la germinación de semillas y el establecimiento de plántulas es una de las principales limitaciones para la restauración de áreas degradadas, incluido el bosque seco tropical conocido como Caatinga. Objetivo: Evaluar la movilización de reservas y metabolitos secundarios durante estas etapas de desarrollo en Erythina velutina. Métodos: Las semillas fueron escarificadas, desinfectadas, embebidas, sembradas entre toallas de papel e incubadas bajo condiciones controladas. Cultivamos las plántulas hidropónicamente en un invernadero. Recolectamos los cotiledones en la imbibición de la semilla, la protrusión de la radícula, la emergencia del hipocótilo, la formación del gancho apical y la expansión de las hojas cordiformes, la primera y segunda hoja trifoliada. Resultados: Las semillas contenían 20 % de almidón, 14.5 % de proteínas de almacenamiento, 11.6 % de lípidos neutros y 5.7 % de azúcares no reductores en peso seco. Los azúcares solubles se consumieron desde la emergencia del hipocótilo hasta la formación del gancho apical. Las principales reservas se movilizaron desde la formación del gancho apical hasta la expansión de la primera hoja trifoliada. La actividad enzimática aumentó desde la mitad hasta el final del establecimiento de las plántulas, movilizando almidón, aceites y proteínas. Se detectaron derivados de terpenoides, flavonoides, ácidos fenólicos y alcaloides. Los flavonoides y los ácidos fenólicos estuvieron en casi todas las etapas y los derivados terpenoides desaparecieron en la expansión de las hojas cordiformes. Conclusión: Los azúcares solubles apoyan el crecimiento temprano de las plántulas; el almidón, los aceites y las proteínas se movilizan simultáneamente desde el establecimiento medio hasta el final por amilasas, lipasas y proteasas ácidas. Los cotiledones contienen metabolitos secundarios, que pueden actuar en la defensa de las plántulas. El alto contenido de reservas y los metabolitos secundarios en los cotiledones podría permitir que las plántulas de E. velutina toleren estrés, validando su uso en la restauración de áreas degradadas.


Asunto(s)
Germinación , Erythrina , Restauración y Remediación Ambiental/métodos , Fabaceae , Brasil
7.
Brain Sci ; 13(12)2023 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-38137059

RESUMEN

APOE ε4 polymorphism has been recently described as a possible association with cognitive deficits in COVID-19 patients. This research aimed to establish the correlation between COVID-19 and cognitive impairment, and the APOE gene polymorphism among outpatients. We performed a cross-sectional study with confirmed COVID-19 patients and neurological symptoms that persisted for more than three months from onset. APOE genotypes were determined. The final number of patients included in this study was 219, of which 186 blood samples were collected for APOE genotyping, evaluated 4.5 months after COVID-19. Among the participants, 143 patients (65.3%) reported memory impairment symptoms as their primary concern. However, this complaint was objectively verified through screening tests (Addenbrooke Cognitive Examination-Revised and Mini-Mental State Examination) in only 36 patients (16.4%). The group experiencing cognitive decline exhibited a higher prevalence of the APOE ε4 allele than the normal group (30.8% vs. 16.4%, respectively, p = 0.038). Furthermore, the APOE ε4 allele and anxiety symptoms remained significant after multivariate analysis. This study assessed an outpatient population where cognitive changes were the primary complaint, even in mild cases. Moreover, the ε4 allele, sleep disorders, and anxiety symptoms were more frequent in the cognitive decline group.

8.
Ir J Med Sci ; 2023 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-37882949

RESUMEN

Despite the undeniable effect of vaccination against COVID-19 in reducing disease severity, there is still a need to monitor and limit SARS-CoV-2 circulation and transmission. Thus, this study evaluated the presence of the SARS-CoV-2 genome on the surfaces of highly touched objects manipulated in the biological sample collection point and at the reception unit of the diagnostic laboratory. Surfaces were sampled once a week, for 6 weeks, between September 18th and October 23rd, 2020. RT-qPCR was used for SARS-CoV-2 detection. The coolers for biological sample transportation and the envelope containing the patient form were the objects with the highest occurrence of viral genome detection, although it was detected in each object in only two of the 6 evaluations. And the SARS-CoV-2 genome was detected just once on the vehicle steering wheel, computer keyboard, bathroom door handle and disinfection bench. The virus genome was not detected in any object on three of the six evaluations. And eight was the largest number of surfaces contaminated by the virus genome on one occasion. The reduced incidence of object contamination by the SARS-CoV-2 genome can be explained by the exposure of the objects to environmental conditions and the adoption of virus-spread containment measures. It can also reflect the low incidence of SARS-CoV-2 during the study's development period. Despite the low frequency of SARS-CoV-2 genome detection, our findings show that the virus was present in the environment at some point. This highlights the importance of adopting personal preventive measures to reduce respiratory virus spread, especially during epidemics and outbreaks.

9.
J Virol ; 97(7): e0041123, 2023 07 27.
Artículo en Inglés | MEDLINE | ID: mdl-37395647

RESUMEN

New representatives of the phylum Nucleocytoviricota have been rapidly described in the last decade. Despite this, not all viruses of this phylum are allocated to recognized taxonomic families, as is the case for orpheovirus, pithovirus, and cedratvirus, which form the proposed family Pithoviridae. In this study, we performed comprehensive comparative genomic analyses of 8 pithovirus-like isolates, aiming to understand their common traits and evolutionary history. Structural and functional genome annotation was performed de novo for all the viruses, which served as a reference for pangenome construction. The synteny analysis showed substantial differences in genome organization between these viruses, with very few and short syntenic blocks shared between orpheovirus and its relatives. It was possible to observe an open pangenome with a significant increase in the slope when orpheovirus was added, alongside a decrease in the core genome. Network analysis placed orpheovirus as a distant and major hub with a large fraction of unique clusters of orthologs, indicating a distant relationship between this virus and its relatives, with only a few shared genes. Additionally, phylogenetic analyses of strict core genes shared with other viruses of the phylum reinforced the divergence of orpheovirus from pithoviruses and cedratviruses. Altogether, our results indicate that although pithovirus-like isolates share common features, this group of ovoid-shaped giant viruses presents substantial differences in gene contents, genomic architectures, and the phylogenetic history of several core genes. Our data indicate that orpheovirus is an evolutionarily divergent viral entity, suggesting its allocation to a different viral family, Orpheoviridae. IMPORTANCE Giant viruses that infect amoebae form a monophyletic group named the phylum Nucleocytoviricota. Despite being genomically and morphologically very diverse, the taxonomic categories of some clades that form this phylum are not yet well established. With advances in isolation techniques, the speed at which new giant viruses are described has increased, escalating the need to establish criteria to define the emerging viral taxa. In this work, we performed a comparative genomic analysis of representatives of the putative family Pithoviridae. Based on the dissimilarity of orpheovirus from the other viruses of this putative family, we propose that orpheovirus be considered a member of an independent family, Orpheoviridae, and suggest criteria to demarcate families consisting of ovoid-shaped giant viruses.


Asunto(s)
Genoma Viral , Virus Gigantes , Filogenia , Humanos , Genoma Viral/genética , Genómica , Virus Gigantes/clasificación , Virus Gigantes/genética , Variación Genética , Evolución Molecular
10.
Braz J Microbiol ; 54(3): 1853-1858, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37454038

RESUMEN

Dengue, Chikungunya, and Zika viruses are arthropod-borne viruses (arboviruses) that infect millions of individuals in tropical and subtropical regions. In the Americas, arboviruses represent a major public health problem, especially among vulnerable groups such as the elderly, children, and pregnant women. In this study, the seroprevalence of IgM or IgG against these arboviruses in pregnant, young women in the city of Diamantina, Minas Gerais, Brazil, and the influence of sociodemographic factors on the incidence/prevalence of infection in this group were investigated. A cross-sectional investigation was conducted on a total of 135 pregnant women for Dengue and Chikungunya IgM and 88 pregnant women for Zika IgG. Dengue IgM was found on the serum of twenty participants (14.8%) and only one woman (0.7%) tested positive for Chikungunya IgM. Zika IgG was found in three (3.4%) participants and 2 women who tested positive for Zika virus were also positive for Dengue virus IgM. Although the arboviruses seroprevalence was higher frequency among young (20-25 years old), brown and high school women, with a monthly income of 1-3 minimum wages, no association between these sociodemographic factors and arboviruses seroprevalence was found.


Asunto(s)
Fiebre Chikungunya , Virus Chikungunya , Virus del Dengue , Dengue , Infección por el Virus Zika , Virus Zika , Niño , Humanos , Femenino , Embarazo , Anciano , Adulto Joven , Adulto , Fiebre Chikungunya/epidemiología , Mujeres Embarazadas , Brasil/epidemiología , Estudios Seroepidemiológicos , Estudios Transversales , Infección por el Virus Zika/epidemiología , Anticuerpos Antivirales , Inmunoglobulina G , Inmunoglobulina M
11.
J Med Virol ; 95(6): e28859, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37314232

RESUMEN

Since 1999, Vaccinia virus (VACV) has been described as a causative agent of bovine vaccinia (BV), a zoonotic disease that occurs mainly in rural areas of Brazil. However, the circulation of VACV in urban environments and its associated burden has been poorly explored. Moreover, the current monkeypox (mpox) outbreak has raised questions regarding the immune status of the worldwide population previous vaccinated against smallpox. Hence, we conducted a cross-sectional study to better understand the prevalence of anti-OPV neutralizing antibodies (NA) and related exposure factors in a susceptible urban population of Brazil. A total of 372 individuals were sampled, yielding an overall seroprevalence of 16.9% (CI95% = 13.4-21.1), and antibodies titers ranging from 100 to 800 neutralizing units/mL. The prevalence of NA among individuals potentially vaccinated against smallpox (≥36 years old [yo]) was 24.9% (IC 95% = 19.5-31.2), and among those unvaccinated (<36yo) was 6.7% (IC 95% = 3.7-11.8). Interestingly, contact with horses was pointed out as an exposure factor for the presence of NA, however, the multivariate logistic regression analysis indicated that age ≥36yo and the presence of vaccine take were independently associated with the presence of anti-OPV NA. Our findings suggest that vulnerable populations could be subclinically exposed to VACV in urban areas, drawing attention to alternative routes of zoonotic VACV exposure. Our data is also important for better strategies to mitigate zoonotic OPV infections mainly among vulnerable populations.


Asunto(s)
Enfermedades Transmisibles , Orthopoxvirus , Viruela , Caballos , Humanos , Animales , Bovinos , Población Urbana , Brasil/epidemiología , Prevalencia , Estudios Transversales , Estudios Seroepidemiológicos , Virus Vaccinia , Zoonosis/epidemiología , Anticuerpos Neutralizantes
12.
Cytokine ; 168: 156237, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37257305

RESUMEN

BACKGROUND: Acute bacterial meningitis (ABM) causes excessive activation of N-methyl-D-aspartate receptors (NMDAr), leading to cortical and hippocampal neuron death. As opposite, enteroviral meningitis is more frequently benign. The kynurenine (KYN) pathway is the major catabolic route of tryptophan (TRP) and some of its metabolites are agonists or antagonists of NMDAr. METHODS: In order to investigate the pathogen-specific patterns of KYN pathway modulation in the central nervous system of children with acute meningococcal (MM), pneumococcal (PM) or enteroviral (VM) meningitis, the cerebrospinal fluid (CSF) concentrations of TRP, KYN, kynurenic acid (KYNA) and quinolinic acid (QUINA) were evaluated by ultra-high performance liquid chromatography (uHPLC) coupled to mass spectrometry. In addition, CSF levels of IL-6, IL-10 and TNF-α were quantified by multi-analyte flow assay. The data was mined and integrated using statistical and machine learning methods. RESULTS: The three forms of meningitis investigated herein up-regulated the neurotoxic branch of the KYN pathway within the intrathecal space. However, this response, represented by the concentration of QUINA, was six and nine times higher in PM patients compared to MM or VM, respectively. CSF levels of IL-6, TNF-α, and IL-10 were increased in MM and PM patients when compared to controls. In VM, CSF IL-6 and IL-10, but not TNF-α were increased compared to controls, although not reaching the high levels found in bacterial meningitis. No correlation was found between the concentrations or the ratios of any pair of KYN metabolites and any cytokine or standard cytochemical parameter tested. CONCLUSIONS: CNS infection with meningococci, pneumococci, and enteroviruses intrathecally activate the KYN pathway, favoring its neurotoxic branch. However, in PM, higher CSF levels of QUINA, compared to MM and VM, may contribute to its poorer neurologic outcome.


Asunto(s)
Meningitis Bacterianas , Meningitis Neumocócica , Niño , Humanos , Quinurenina/metabolismo , Interleucina-10 , Interleucina-6 , Triptófano/metabolismo , Sistema Nervioso Central/metabolismo
13.
Viruses ; 15(4)2023 03 25.
Artículo en Inglés | MEDLINE | ID: mdl-37112823

RESUMEN

Vaccinia virus (VACV) is the causative agent of an emerging viral zoonosis called bovine vaccinia (BV). Several studies have documented characteristics of VACV infections in Brazil; however, the manner in which this virus is maintained in wildlife remains unknown. This work investigated the presence of viral DNA and anti-orthopoxvirus (OPXV) antibodies in samples collected from small mammals in a VACV-endemic area in Minas Gerais, Brazil, in the absence of current outbreaks. Samples did not show amplification of OPXV DNA in molecular tests. However, 5/142 serum samples demonstrated the presence of anti-OPXV neutralizing antibodies in serological tests. These data reinforce the involvement of small mammals in the natural cycle of VACV, highlighting the need for further ecological studies to better understand how this virus is maintained in nature and to develop measures to prevent BV outbreaks.


Asunto(s)
Enfermedades Transmisibles , Orthopoxvirus , Vaccinia , Animales , Bovinos , Orthopoxvirus/genética , Zoonosis , Brasil/epidemiología , Virus Vaccinia/genética , Vaccinia/epidemiología , Vaccinia/veterinaria , Enfermedades Transmisibles/epidemiología , Brotes de Enfermedades , Mamíferos
14.
Emerg Infect Dis ; 29(6): 1270-1273, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37069695

RESUMEN

Phylogenetic analysis of 34 monkeypox virus genome sequences isolated from patients in Minas Gerais, Brazil, revealed initial importation events in early June 2022, then community transmission within the state. All generated genomes belonged to the B.1 lineage responsible for a global mpox outbreak. These findings can inform public health measures.


Asunto(s)
Monkeypox virus , Mpox , Humanos , Monkeypox virus/genética , Filogenia , Brasil/epidemiología , Brotes de Enfermedades , Genómica , Mpox/epidemiología
15.
ACS Appl Bio Mater ; 6(3): 1011-1018, 2023 03 20.
Artículo en Inglés | MEDLINE | ID: mdl-36791416

RESUMEN

A detailed insight about the molecular organization behind spider silk assembly is valuable for the decoding of the unique properties of silk. The recombinant partial spider silk protein 4RepCT contains four poly-alanine/glycine-rich repeats followed by an amphiphilic C-terminal domain and has shown the capacity to self-assemble into fibrils on hydrophobic surfaces. We herein use molecular dynamic simulations to address the structure of 4RepCT and its different parts on hydrophobic versus hydrophilic surfaces. When 4RepCT is placed in a wing arrangement model and periodically repeated on a hydrophobic surface, ß-sheet structures of the poly-alanine repeats are preserved, while the CT part is settled on top, presenting a fibril with a height of ∼7 nm and a width of ∼11 nm. Both atomic force microscopy and cryo-electron microscopy imaging support this model as a possible fibril formation on hydrophobic surfaces. These results contribute to the understanding of silk assembly and alignment mechanism onto hydrophobic surfaces.


Asunto(s)
Seda , Animales , Seda/química , Microscopía por Crioelectrón , Proteínas Recombinantes/química
16.
Viruses ; 15(1)2023 01 14.
Artículo en Inglés | MEDLINE | ID: mdl-36680274

RESUMEN

Dengue and obesity are currently highly prevalent conditions worldwide and the association between these two conditions may result in greater risk for DENV infection and disease severity. In this study the association between obesity and recent, inapparent dengue was investigated. Serum DENV IgM and NS1 were evaluated in 49 adult volunteers (15 lean and 34 individuals with obesity, according to body mass index), between September 2017 and June 2018. Adiposity, endocrine, metabolic, and immune data of the participants were also obtained. None of the study participants tested positive for the DENV NS1 antigen. DENV IgM was detected in 33.3% of the lean individuals, and in 44.1% of those with obesity; the presence of DENV IgM was not associated with body mass index (OR = 1.32, 95% CI = 0.59-2.98, p = 0.48). However, body fat index was higher in obese individuals who had recent inapparent dengue (14.7 ± 3.1 versus 12.7 ± 2.1 kg/m2, p = 0.04), as was the expression of CD11b by classical (CD14++CD16-) monocytes (1103.0 ± 311.3 versus 720.3 ± 281.1 mean fluoresce intensity). Our findings suggest an association between adiposity and recent inapparent dengue and the involvement of classical monocytes in this association.


Asunto(s)
Virus del Dengue , Dengue , Adulto , Humanos , Dengue/epidemiología , Monocitos , Prevalencia , Anticuerpos Antivirales , Inmunoglobulina M , Obesidad/epidemiología , Proteínas no Estructurales Virales , Ensayo de Inmunoadsorción Enzimática
17.
Mol Psychiatry ; 28(2): 553-563, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-35701598

RESUMEN

People recovered from COVID-19 may still present complications including respiratory and neurological sequelae. In other viral infections, cognitive impairment occurs due to brain damage or dysfunction caused by vascular lesions and inflammatory processes. Persistent cognitive impairment compromises daily activities and psychosocial adaptation. Some level of neurological and psychiatric consequences were expected and described in severe cases of COVID-19. However, it is debatable whether neuropsychiatric complications are related to COVID-19 or to unfoldings from a severe infection. Nevertheless, the majority of cases recorded worldwide were mild to moderate self-limited illness in non-hospitalized people. Thus, it is important to understand what are the implications of mild COVID-19, which is the largest and understudied pool of COVID-19 cases. We aimed to investigate adults at least four months after recovering from mild COVID-19, which were assessed by neuropsychological, ocular and neurological tests, immune markers assay, and by structural MRI and 18FDG-PET neuroimaging to shed light on putative brain changes and clinical correlations. In approximately one-quarter of mild-COVID-19 individuals, we detected a specific visuoconstructive deficit, which was associated with changes in molecular and structural brain imaging, and correlated with upregulation of peripheral immune markers. Our findings provide evidence of neuroinflammatory burden causing cognitive deficit, in an already large and growing fraction of the world population. While living with a multitude of mild COVID-19 cases, action is required for a more comprehensive assessment and follow-up of the cognitive impairment, allowing to better understand symptom persistence and the necessity of rehabilitation of the affected individuals.


Asunto(s)
COVID-19 , Disfunción Cognitiva , Adulto , Humanos , COVID-19/complicaciones , Neuroimagen , Encéfalo/diagnóstico por imagen , Disfunción Cognitiva/diagnóstico , Imagen por Resonancia Magnética
18.
Rev. Bras. Odontol. Leg. RBOL ; 9(3): 35-45, 2022-12-30.
Artículo en Portugués | LILACS-Express | LILACS | ID: biblio-1524872

RESUMEN

A violência contra a mulher corresponde a qualquer ação ou omissão, baseada em gênero, causando morte, lesão, sofrimento físico, sexual, entre outros, contrariando as leis de proteção à vítima, como a Lei Maria da Penha. Devido à alta exposição das estruturas anatômicas da face, é comum a presença de lesões nesta região. A análise pericial dessas áreas carece de conhecimento especializado acerca da anatomia bucomaxilofacial, portanto o cirurgião dentista é essencial no exame pericial, objetivando auxiliar na produção de provas e, consequentemente, na materialização da justiça. A COVID-19 trouxe como consequências o aumento da carga doméstica, estresse, limitações e tensões dentro dos lares. O objetivo do presente trabalho é explorar a violência doméstica contra a mulher durante a pandemia em Sergipe. Foram analisados 304 laudos no período de 2020-2021, no Instituto Médico Legal de Sergipe (IML-SE), exibindo a faixa etária mais acometida de 17 a 39 anos, agredidas pelo companheiro atual (35,86%). As agressões se iniciam verbalmente, evoluindo para violência física, com instrumentos contundentes (82,46%), produzindo lesões contusas (84,64%), na face (10,81%). Conclui-se que a violência doméstica persistiu como um problema de saúde pública, crescente, durante a pandemia, no estado de Sergipe. Sendo assim, sugere-se a discussão sobre formas de aplicação mais eficientes das medidas legais existentes, no sentido de controlar e prevenir tal situação


Domestic violence occurs mostly in the family's environment, and it can be committed by close relatives or trusted family members. The facial region is the most affected because it is the most exposed and is the choice of aggressors, making the forensic dentist essential in these expertises. The social distancing to contain COVID-19, resulted in increase of domestic affairs, stress and limitations, leading To increased tensions. The objective of this work was to raise data about the panorama of domestic violence against women in the state of Sergipe during the pandemic. We analyzed 304 forensic reports of women victims of domestic violence in the period of 2020-2021 written by dentists (64%) and medical examiners (36%), with the most affected age group from 17 to 39 years old, assaulted by their current partner (35, 86%), with blunt force (82.46%), producing blunt injuries (84.64%), mostly in the region of the eye orbit (17.48%), which were mostly ranked as offense to physical integrity or health (92%).Finally, violence against women keeps increasing, starting as verbal and then physical abuse, ending in many cases as feminicide. We suggest studies regarding more efficient ways to apply the existent legal instruments in order to reduce domestic violence in Brazil

19.
Metabolites ; 12(11)2022 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-36355139

RESUMEN

The COVID-19 pandemic boosted the development of diagnostic tests to meet patient needs and provide accurate, sensitive, and fast disease detection. Despite rapid advancements, limitations related to turnaround time, varying performance metrics due to different sampling sites, illness duration, co-infections, and the need for particular reagents still exist. As an alternative diagnostic test, we present urine analysis through flow-injection-tandem mass spectrometry (FIA-MS/MS) as a powerful approach for COVID-19 diagnosis, targeting the detection of amino acids and acylcarnitines. We adapted a method that is widely used for newborn screening tests on dried blood for urine samples in order to detect metabolites related to COVID-19 infection. We analyzed samples from 246 volunteers with diagnostic confirmation via PCR. Urine samples were self-collected, diluted, and analyzed with a run time of 4 min. A Lasso statistical classifier was built using 75/25% data for training/validation sets and achieved high diagnostic performances: 97/90% sensitivity, 95/100% specificity, and 95/97.2% accuracy. Additionally, we predicted on two withheld sets composed of suspected hospitalized/symptomatic COVID-19-PCR negative patients and patients out of the optimal time-frame collection for PCR diagnosis, with promising results. Altogether, we show that the benchmarked FIA-MS/MS method is promising for COVID-19 screening and diagnosis, and is also potentially useful after the peak viral load has passed.

20.
Materials (Basel) ; 15(22)2022 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-36431390

RESUMEN

Commercial Yttria-tetragonal zirconia polycrystalline (Y-TZP) was subjected to surface treatments, and the bond strength of dual resin cement to Y-TZP and failure modes were evaluated. Disks (12 mm × 2 mm), cylinders (7 mm × 3.3 mm), and bars (25 mm × 5 mm × 2 mm) were milled from Y-TZP CAD-CAM blocks, divided into seven groups, and subjected to different surface treatments; silicatization was used as control. On the basis of the literature, this study evaluated modifications with films containing SiO2 nanoparticles and silane; SiO2+ZrO2­SiO2 (50%) and ZrO2 (50%) nanoparticles, SiO2+ZrO2/Silane-SiO2 (50%) and ZrO2 (50%) nanoparticles, and silane. Specimens were analyzed by wettability (n = 3), surface free energy (n = 3), X-ray diffraction (n = 1), Fourier transform infrared spectroscopy (FTIR) (n = 1), roughness (n = 5), shear bond test (n = 10), and dynamic modulus (n = 3). Specimens treated with hydrofluoric acid­HF 40% presented significantly higher contact angle and lowest surface free energy (p < 0.05). The SiO2/Silane presented crystalline SiO2 on the surface. The surface roughness was significantly higher for groups treated with nanofilms (p < 0.05). Shear bond strength was significantly higher for silicatization, HF 40%/silicatization, SiO2/Silane, and SiO2+ZrO2/Silane groups. The proposed treatments with nanofilms had potentially good results without prejudice to the physicochemical characteristics of zirconia. Generally, groups that underwent silica surface deposition and silanization had better bond strength (p < 0.005).

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