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1.
Front Physiol ; 14: 1130914, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37035666

RESUMO

Bilateral index for upper limbs was determined for maximal force, speed and power in 18 male handball players. Variables were individually assessed with a functional electromechanical dynamometer during unilateral and bilateral bench press push-off for 40%, 60%, and 75% of the maximal isometric force. Limb dominance (symmetry indices) and load effects in the bilateral index were analysed. Bilateral index showed a bilateral deficit for power (range = -8.50 to -41.48) and velocity (range = -11.15 to -38.41), that increases with the load (p < 0.05). For maximum force, a bilateral facilitation (range = 2.26-5.57), which did not vary significantly as a function of load, was observed. Symmetry indices showed no association with the bilateral index (40% load: r = 0.45, 60% load: r = 0.05, 75% load: r = 0.39). These results contribute to understanding the phenomenon; however, individual-to-individual observation reflects that caution should be kept when assessing an individual athlete. In conclusion, bilateral deficit or facilitation for bench press depends on the variable considered, whereas its magnitude depends on the load. Moreover, limb dominance does not affect it. This finding must be regarded as a general trend, but a different situation may occur during the assessment of a particular athlete.

2.
ACS Cent Sci ; 9(3): 393-404, 2023 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-36968546

RESUMO

The emergence of a polybasic cleavage motif for the protease furin in SARS-CoV-2 spike has been established as a major factor for human viral transmission. The region N-terminal to that motif is extensively mutated in variants of concern (VOCs). Besides furin, spikes from these variants appear to rely on other proteases for maturation, including TMPRSS2. Glycans near the cleavage site have raised questions about proteolytic processing and the consequences of variant-borne mutations. Here, we identify that sialic acid-containing O-linked glycans on Thr678 of SARS-CoV-2 spike influence furin and TMPRSS2 cleavage and posit O-linked glycosylation as a likely driving force for the emergence of VOC mutations. We provide direct evidence that the glycosyltransferase GalNAc-T1 primes glycosylation at Thr678 in the living cell, an event that is suppressed by mutations in the VOCs Alpha, Delta, and Omicron. We found that the sole incorporation of N-acetylgalactosamine did not impact furin activity in synthetic O-glycopeptides, but the presence of sialic acid reduced the furin rate by up to 65%. Similarly, O-glycosylation with a sialylated trisaccharide had a negative impact on TMPRSS2 cleavage. With a chemistry-centered approach, we substantiate O-glycosylation as a major determinant of spike maturation and propose disruption of O-glycosylation as a substantial driving force for VOC evolution.

3.
Vet Res Commun ; 47(2): 615-629, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36229725

RESUMO

Severe Acute Respiratory Syndrome Coronavirus 2 is the causative agent of Coronavirus Disease 2019 in humans. Among domestic animals, cats are more susceptible to SARS-CoV-2 than dogs. The detection of anti-SARS-CoV-2 antibodies in seemingly healthy cats and/or infected cats which are in close contact with infected humans has been described. The presence of animals that tested positive by serology or molecular techniques could represent a potential transmission pathway of SARS-CoV-2 that can spill over into urban wildlife. This study analyses the seroprevalence variation of SARS-CoV-2 in stray cats from different waves of outbreaks in a geographical area where previous seroepidemiological information of SARS-CoV-2 was available and investigate if SARS-CoV-2-seropositive cats were exposed to other co-infections causing an immunosuppressive status and/or a chronic disease that could lead to a SARS-CoV-2 susceptibility. For this purpose, a total of 254 stray cats from Zaragoza (Spain) were included. This analysis was carried out by the enzyme-linked immunosorbent assay using the receptor binding domain of Spike antigen and confirmed by serum virus neutralization assay. The presence of co-infections including Toxoplasma gondii, Leishmania infantum, Dirofilaria immitis, feline calicivirus, feline herpesvirus type 1, feline leukemia virus and feline immunodeficiency virus, was evaluated using different serological methods. A seropositivity of 1.57% was observed for SARS-CoV-2 including the presence of neutralizing antibodies in three cats. None of the seropositive to SARS-CoV-2 cats were positive to feline coronavirus, however, four SARS-CoV-2-seropositive cats were also seropositive to other pathogens such as L. infantum, D. immitis and FIV (n = 1), L. infantum and D. immitis (n = 1) and L. infantum alone (n = 1).Considering other pathogens, a seroprevalence of 16.54% was detected for L. infantum, 30.31% for D. immitis, 13.78%, for T. gondii, 83.86% for feline calicivirus, 42.52% for feline herpesvirus type 1, 3.15% for FeLV and 7.87% for FIV.Our findings suggest that the epidemiological role of stray cats in SARS-CoV-2 transmission is scarce, and there is no increase in seropositivity during the different waves of COVID-19 outbreaks in this group of animals. Further epidemiological surveillances are necessary to determine the risk that other animals might possess even though stray cats do not seem to play a role in transmission.


Assuntos
COVID-19 , Doenças do Gato , Coinfecção , Dirofilaria immitis , Doenças do Cão , Vírus da Imunodeficiência Felina , Humanos , Gatos , Animais , Cães , Doenças do Gato/epidemiologia , SARS-CoV-2 , Coinfecção/epidemiologia , Coinfecção/veterinária , Espanha/epidemiologia , Estudos Soroepidemiológicos , Estudos Transversais , COVID-19/epidemiologia , COVID-19/veterinária , Vírus da Leucemia Felina , Surtos de Doenças , Doenças do Cão/epidemiologia
4.
Nat Commun ; 13(1): 4324, 2022 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-35882872

RESUMO

Mucinases of human gut bacteria cleave peptide bonds in mucins strictly depending on the presence of neighboring O-glycans. The Akkermansia muciniphila AM0627 mucinase cleaves specifically in between contiguous (bis) O-glycans of defined truncated structures, suggesting that this enzyme may recognize clustered O-glycan patches. Here, we report the structure and molecular mechanism of AM0627 in complex with a glycopeptide containing a bis-T (Galß1-3GalNAcα1-O-Ser/Thr) O-glycan, revealing that AM0627 recognizes both the sugar moieties and the peptide sequence. AM0627 exhibits preference for bis-T over bis-Tn (GalNAcα1-O-Ser/Thr) O-glycopeptide substrates, with the first GalNAc residue being essential for cleavage. AM0627 follows a mechanism relying on a nucleophilic water molecule and a catalytic base Glu residue. Structural comparison among mucinases identifies a conserved Tyr engaged in sugar-π interactions in both AM0627 and the Bacteroides thetaiotaomicron BT4244 mucinase as responsible for the common activity of these two mucinases with bis-T/Tn substrates. Our work illustrates how mucinases through tremendous flexibility adapt to the diversity in distribution and patterns of O-glycans on mucins.


Assuntos
Glicoproteínas , Polissacarídeos , Carboidratos , Glicopeptídeos/química , Humanos , Intestinos , Mucinas/química , Polissacarídeo-Liases , Polissacarídeos/química , República da Coreia , Açúcares
5.
Nat Commun ; 13(1): 2398, 2022 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-35504880

RESUMO

C1GalT1 is an essential inverting glycosyltransferase responsible for synthesizing the core 1 structure, a common precursor for mucin-type O-glycans found in many glycoproteins. To date, the structure of C1GalT1 and the details of substrate recognition and catalysis remain unknown. Through biophysical and cellular studies, including X-ray crystallography of C1GalT1 complexed to a glycopeptide, we report that C1GalT1 is an obligate GT-A fold dimer that follows a SN2 mechanism. The binding of the glycopeptides to the enzyme is mainly driven by the GalNAc moiety while the peptide sequence provides optimal kinetic and binding parameters. Interestingly, to achieve glycosylation, C1GalT1 recognizes a high-energy conformation of the α-GalNAc-Thr linkage, negligibly populated in solution. By imposing this 3D-arrangement on that fragment, characteristic of α-GalNAc-Ser peptides, C1GalT1 ensures broad glycosylation of both acceptor substrates. These findings illustrate a structural and mechanistic blueprint to explain glycosylation of multiple acceptor substrates, extending the repertoire of mechanisms adopted by glycosyltransferases.


Assuntos
Glicopeptídeos , Mucinas , Sequência de Aminoácidos , Cristalografia por Raios X , Glicopeptídeos/química , Glicosilação , Mucinas/metabolismo
6.
Transbound Emerg Dis ; 69(3): 1056-1064, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-33686768

RESUMO

A new coronavirus known as SARS-CoV-2 emerged in Wuhan in 2019 and spread rapidly to the rest of the world causing the pandemic disease named coronavirus disease of 2019 (COVID-19). Little information is known about the impact this virus can cause upon domestic and stray animals. The potential impact of SARS-CoV-2 has become of great interest in cats due to transmission among domestic cats and the severe phenotypes described recently in a domestic cat. In this context, there is a public health warning that needs to be investigated in relation with the epidemiological role of this virus in stray cats. Consequently, in order to know the impact of the possible transmission chain, blood samples were obtained from 114 stray cats in the city of Zaragoza (Spain) and tested for SARS-CoV-2 and other selected pathogens susceptible to immunosuppression including Toxoplasma gondii, Leishmania infantum, feline leukaemia virus (FeLV) and feline immunodeficiency virus (FIV) from January to October 2020. Four cats (3.51%), based on enzyme-linked immunosorbent assay (ELISA) using the receptor binding domain (RBD) of Spike antigen, were seroreactive to SARS-CoV-2. T. gondii, L. infantum, FeLV and FIV seroprevalence was 12.28%, 16.67%, 4.39% and 19.30%, respectively. Among seropositive cats to SARS-CoV-2, three cats were also seropositive to other pathogens including antibodies detected against T. gondii and FIV (n = 1); T. gondii (n = 1); and FIV and L. infantum (n = 1). The subjects giving positive for SARS-CoV-2 were captured in urban areas of the city in different months: January 2020 (2/4), February 2020 (1/4) and July 2020 (1/4). This study revealed, for the first time, the exposure of stray cats to SARS-CoV-2 in Spain and the existence of concomitant infections with other pathogens including T. gondii, L. infantum and FIV, suggesting that immunosuppressed animals might be especially susceptible to SARS-CoV-2 infection.


Assuntos
COVID-19 , Doenças do Gato , Coinfecção , Vírus da Imunodeficiência Felina , Animais , Animais Selvagens , COVID-19/epidemiologia , COVID-19/veterinária , Doenças do Gato/epidemiologia , Gatos , Coinfecção/epidemiologia , Coinfecção/veterinária , Humanos , Vírus da Leucemia Felina , SARS-CoV-2 , Estudos Soroepidemiológicos , Espanha/epidemiologia
7.
Antioxidants (Basel) ; 10(9)2021 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-34573078

RESUMO

Lignin biodegradation has been extensively studied in white-rot fungi, which largely belong to order Polyporales. Among the enzymes that wood-rotting polypores secrete, lignin peroxidases (LiPs) have been labeled as the most efficient. Here, we characterize a similar enzyme (ApeLiP) from a fungus of the order Agaricales (with ~13,000 described species), the soil-inhabiting mushroom Agrocybe pediades. X-ray crystallography revealed that ApeLiP is structurally related to Polyporales LiPs, with a conserved heme-pocket and a solvent-exposed tryptophan. Its biochemical characterization shows that ApeLiP can oxidize both phenolic and non-phenolic lignin model-compounds, as well as different dyes. Moreover, using stopped-flow rapid spectrophotometry and 2D-NMR, we demonstrate that ApeLiP can also act on real lignin. Characterization of a variant lacking the above tryptophan residue shows that this is the oxidation site for lignin and other high redox-potential substrates, and also plays a role in phenolic substrate oxidation. The reduction potentials of the catalytic-cycle intermediates were estimated by stopped-flow in equilibrium reactions, showing similar activation by H2O2, but a lower potential for the rate-limiting step (compound-II reduction) compared to other LiPs. Unexpectedly, ApeLiP was stable from acidic to basic pH, a relevant feature for application considering its different optima for oxidation of phenolic and nonphenolic compounds.

8.
Animals (Basel) ; 11(7)2021 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-34359111

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the zoonotic causative agent of coronavirus disease 2019 (COVID-19) that has caused a pandemic situation with millions of infected humans worldwide. Among domestic animals, there have been limited studies regarding the transmissibility and exposure to the infection in natural conditions. Some animals are exposed and/or susceptible to SARS-CoV-2 infection, such as cats, ferrets and dogs. By contrast, there is no information about the susceptibility of ruminants to SARS-CoV-2. This study tested the antibody response in 90 ovine pre-pandemic serum samples and 336 sheep serum samples from the pandemic period (June 2020 to March 2021). In both cases, the animals were in close contact with a veterinary student community composed of more than 700 members. None of the serum samples analyzed was seroreactive based on an enzyme-linked immunosorbent assay (ELISA) using the receptor-binding domain (RBD) of the spike antigen. In this sense, no statistical difference was observed compared to the pre-pandemic sheep. Our results suggest that it seems unlikely that sheep could play a relevant role in the epidemiology of SARS-CoV-2 infection. This is the first study to report the absence of evidence of sheep exposure to SARS-CoV-2 in natural conditions.

9.
Biology (Basel) ; 10(3)2021 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-33801808

RESUMO

Several hundred millions of people have been diagnosed of coronavirus disease 2019 (COVID-19), causing millions of deaths and a high socioeconomic burden. SARS-CoV-2, the causative agent of COVID-19, induces both specific T- and B-cell responses, being antibodies against the virus detected a few days after infection. Passive immunization with hyperimmune plasma from convalescent patients has been proposed as a potentially useful treatment for COVID-19. Using an in-house quantitative ELISA test, we found that plasma from 177 convalescent donors contained IgG antibodies specific to the spike receptor-binding domain (RBD) of SARS-CoV-2, although at very different concentrations which correlated with previous disease severity and gender. Anti-RBD IgG plasma concentrations significantly correlated with the plasma viral neutralizing activity (VN) against SARS-CoV-2 in vitro. Similar results were found using an independent cohort of serum from 168 convalescent health workers. These results validate an in-house RBD IgG ELISA test in a large cohort of COVID-19 convalescent patients and indicate that plasma from all convalescent donors does not contain a high enough amount of anti-SARS-CoV-2-RBD neutralizing IgG to prevent SARS-CoV-2 infection in vitro. The use of quantitative anti-RBD IgG detection systems might help to predict the efficacy of the passive immunization using plasma from patients recovered from SARS-CoV-2.

11.
Rev. bras. ciênc. esporte ; 43: e006520, 2021. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1288257

RESUMO

ABSTRACT This study aimed to describe regularities in soccer goal-ending sequences in the 2016 and 2017 CONMEBOL Libertadores Cups. Observational methodology was used. The sample comprised 699 attack sequences that ended in goal from 250 games played in 2016 and 2017. An ad hoc observational instrument was designed. Data analysis was performed in three complementary ways: sequential, graph theory, and polar coordinates. Two sequences were highlighted: Pass with the head-Shot-Goal and Rebound-Rebound-Shot-Goal. The foot pass action is the most common prior to a shot. In addition, dribbling and conducting were excitatory and inhibitory actions, respectively, to score a goal. In conclusion, the use of open game was relevant to score goals and different patterns were observed.


RESUMO O objetivo foi descrever regularidades nas sequências terminadas em gol nas Copas CONMEBOL Libertadores 2016 e 2017. Foi escolhida a metodologia observacional. A amostra compreendeu 699 sequências de ataques terminadas em gol de 250 jogos disputados em 2016 e 2017. Elaborou-se um instrumento de observação ad hoc. A análise dos dados foi realizada de três maneiras complementares: análise sequencial; teoria dos grafos; e coordenadas polares. Duas sequências foram destacadas: Passe com a cabeça-Chute-Gol e Rebote-Rebote-Chute-Gol. A ação passe com o pé foi a mais comum antes de um tiro. Além disso, dribbling foi uma ação excitatória de marcar um gol e a condução o inibiu. Conclui-se que o uso do jogo aberto foi relevante para marcar gols e diferentes padrões foram observados.


RESUMEN El objetivo fue describir regularidades en las secuencias terminadas en gol en las Copas Libertadores de fútbol 2016 y 2017. Se utilizó la metodología observacional. La muestra comprendió 699 secuencias de ataque que terminaron en gol de 250 partidos jugados en 2016 y 2017. Se diseñó un instrumento de observación ad hoc. El análisis de datos se realizó a través de tres maneras complementarias: análisis secuencial; teoría de grafos y coordenadas polares. Se destacaron dos secuencias: Pase con la cabeza-Remate-Gol y Rebote-Rebote-Remate-Gol. La acción Pase con el pie fue la más común antes de un tiro. Además, el regate fue una acción excitatoria de marcar un gol y la conducción lo inhibió. En conclusión, la utilización del juego abierto fue relevante para marcar goles y se observaron diferentes patrones.

12.
Artigo em Espanhol | LILACS, UY-BNMED | ID: biblio-1291282

RESUMO

Se presenta el caso de un paciente con antecedente de adenocarcinoma de próstata y diagnóstico de ACV isquémico con transformación hemorrágica. La gammagrafía ósea con Tc-99m MDP complementada con SPECT e imágenes de fusión con TC cerebral simple, realizada a los 15 días, muestra hipercaptación en la región temporal izquierda, correspondiente al ACV en etapa subaguda.


We present the case of a patient with a history of prostate adenocarcinoma with a diagnosis of ischemic stroke with hemorrhagic transformation. Bone scintigraphy with Tc-99m MDP supplemented with SPECT and fusion images with simple cerebral CT, performed at 15 days, shows uptake in the left temporal region, corresponding to stroke in subacute stage


Apresentamos o caso de um paciente com história de adenocarcinoma de próstata com diagnóstico de acidente vascular cerebral isquêmico com transformação hemorrágica. A cintilografia óssea com Tc-99m MDP suplementada com SPECT e imagens de fusão com TC cerebral simple, realizadas aos 15 dias, mostra captação na região temporal esquerda, correspondente ao ACV na fase subaguda


Assuntos
Humanos , Masculino , Idoso de 80 Anos ou mais , Medronato de Tecnécio Tc 99m , Acidente Vascular Cerebral/diagnóstico por imagem , Cintilografia , Tomografia Computadorizada de Emissão de Fóton Único
13.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1390196

RESUMO

RESUMEN El hiperparatiroidismo terciario es una complicación presentada en pacientes con enfermedad renal crónica llevados a trasplante renal cuyo manejo quirúrgico requiere de la ubicación mediante imágenes diagnosticas para garantizar el éxito de esta intervención. Se presenta caso de mujer en hemodiálisis crónica que presentó hiperparatiroidismo terciario por hiperplasia paratiroidea confirmada con Tc-99m MIBI SPECT.


ABSTRACT Tertiary hyperparathyroidism is a complication presented in patients with chronic kidney disease subjected to renal transplantation whose surgical management requires location through diagnostic images to guarantee the success of this intervention. We present the case of a woman on chronic hemodialysis who presented tertiary hyperparathyroidism due to parathyroid hyperplasia confirmed by Tc-99m MIBI SPECT.

14.
Rev. ing. bioméd ; 3(5): 101-105, ene.-jun. 2009. graf
Artigo em Inglês | LILACS | ID: lil-770900

RESUMO

En el siguiente artículo se expone un modelo simple del procedimiento de endoscopia gástrica y un modelo plástico del estómago y de la distensión estomacal. El uso correcto de imágenes ayuda al desarrollo de sistemas de realidad virtual, y presenta más realismo a la simulación. El objetivo del trabajo consiste en experimentar la posibilidad de construir sistemas simuladores de pacientes en Colombia, utilizando la tecnología localmente disponible, a bajo costo y destinados para la formación de estudiantes de medicina.


The following paper deals with a simple model of a gastric endoscopy procedure and a plastic model of the stomach and its distension. The correct use of imaging helps in the development of virtual reality systems, and provides a greater realism to the simulation itself. The goal is to experience the possibility of building patient simulator systems in Colombia, using locally available technology, at low costs and intended for the training of medical students.

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