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1.
Phys Chem Chem Phys ; 26(3): 2228-2241, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38165158

RESUMO

There is experimental evidence that solid mixtures of the rhodium dimer [Cp*RhCl2]2 and benzo[h] quinoline (BHQ) produce two different polymorphic molecular cocrystals called 4α and 4ß under ball milling conditions. The addition of NaOAc to the mixture leads to the formation of the rhodacycle [Cp*Rh-(BHQ)Cl], where the central Rh atom retains its tetracoordinate character. Isolate 4ß reacts with NaOAc leading to the same rhodacycle while isolate 4α does not under the same conditions. We show that the puzzling difference in reactivity between the two cocrystals can be traced back to fundamental aspects of the intermolecular interactions between the BHQ and [Cp*RhCl2]2 fragments in the crystalline environment. To support this view, we report a number of descriptors of the nature and strength of chemical bonds and intermolecular interactions in the extended solids and in a cluster model. We calculate formal quantum mechanical descriptors based on electronic structure, electron density, and binding and interaction energies including an energy decomposition analysis. Without exception, all descriptors point to 4ß being a transient structure higher in energy than 4α with larger local and global electrophilic and nucleophilic powers, a more favorable spatial and energetic distribution of the frontier orbitals, and a more fragile crystal structure.

2.
HIV Med ; 24(9): 990-999, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37128161

RESUMO

INTRODUCTION: HIV prevalence among transgender women is high worldwide. The objectives of the present study were to estimate the current prevalence of HIV and identify factors associated with high HIV burden among transgender women in Paraguay. METHODS: Transgender women aged ≥15 years in four regions of Paraguay were recruited by Starfish sampling between February and March 2021. RESULTS: In total, 322 transgender women were included. Mean age was 31 years (range 15-67), and 102 had positive HIV test results (31.7%, 95% confidence interval [CI] 26.6-37.1). In multivariable analysis, factors associated with HIV infection were age at first intercourse ≤17 years (adjusted odds ratio [aOR] 5.47; 95% CI 1.05-28.42), >10 years difference in age with the last sexual partner (aOR 1.60; 95% CI 1.04-2.46), substance use (mostly cocaine) (aOR 3.00; 95% CI 1.47-6.12), higher risk perception (aOR 3.08; 95% CI 1.53-6.17), not testing for HIV (aOR 1.23; 95% CI 1.09-1.39), and accessed by a peer educator (aOR 3.86; 95% CI 1.77-8.38). CONCLUSIONS: Sexual debut as a minor and a large age difference with sexual partners are associated with high burden of HIV among transgender women in Paraguay. Our study corroborates the finding of cocaine use during sex as a risk factor for HIV. Prevention programmes must address structural and social vulnerabilities to stem the tragically high burden of HIV among transgender women.


Assuntos
Infecções por HIV , Soropositividade para HIV , HIV-1 , Pessoas Transgênero , Humanos , Feminino , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Infecções por HIV/epidemiologia , Paraguai/epidemiologia , Comportamento Sexual , Fatores de Risco , Prevalência
3.
J Anat ; 243(5): 842-859, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37278321

RESUMO

We analyzed pedicle bone from roe bucks that had died around antler casting or shortly before or during the rutting period. Pedicles obtained around antler casting were highly porous and showed signs of intense osteoclastic activity that had caused the formation of an abscission line. Following the detachment of the antler plus a portion of pedicle bone, osteoclastic activity in the pedicles continued for some time, and new bone was deposited onto the separation plane of the pedicle stump, leading to partial pedicle restoration. Pedicles obtained around the rutting period were compact structures. The newly formed, often very large secondary osteons, which had filled the resorption cavities, exhibited a lower mineral density than the persisting older bone. The middle zones of the lamellar infilling frequently showed hypomineralized lamellae and enlarged osteocyte lacunae. This indicates a deficiency in mineral elements during the formation of these zones that occurred along with peak antler mineralization. We suggest that growing antlers and compacting pedicles compete for mineral elements, with the rapidly growing antlers being the more effective sinks. The competition between the two simultaneously mineralizing structures is probably more severe in Capreolus capreolus than in other cervids. This is because roe bucks regrow their antlers during late autumn and winter, a period of limited food and associated mineral supply. The pedicle is a heavily remodeled bone structure with distinct seasonal variation in porosity. Pedicle remodeling differs in several aspects from the normal bone remodeling process in the mammalian skeleton.


Assuntos
Chifres de Veado , Reabsorção Óssea , Cervos , Animais , Chifres de Veado/anatomia & histologia , Cervos/anatomia & histologia , Osso e Ossos , Minerais
4.
Pediatr Res ; 94(6): 2077-2084, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37454185

RESUMO

BACKGROUND: Youth is a vulnerable period. To classify lifestyle behaviors and its relationship with health-related outcomes of Spanish children and adolescents. METHODS: Cross-sectional study including 3261 children aged 7.5-17.5 y (52.8% females). Physical activity (PA), screen-time, sleep time, adherence to Mediterranean diet (MD), weight status (WS) by validated methods. Cluster analysis was run considering chronological age. RESULTS: Six clusters were identified: C1: high screen time, low adherence to MD and sleep time (n = 431,13.20%); C2: high WS, medium adherence to MD,high sleep time, and low screen time (n = 466,14.30%); C3: young group with low screen time and high PA, adherence to MD and sleep (n = 537,16.40%); C4: worst profile regarding adherence to MD, PA, WS and sleep time (n = 609,18.70%); C5: low screen time and PA, high sleep time (n = 804,24.70%); C6: high PA and screen time, low WS (n = 414,12.70%). Mean absolute values were statistically different among PA levels, screen and sleep time, adherence to MD, age, and WS (all p < 0.001). CONCLUSIONS: The most prevalent pattern was low levels of PA, MD, and screen time, and high sleep time. The second most prevalent was characterized by very low levels of PA, sleep time, and adherence to MD, and high screen time, and WS in adolescents. IMPACT STATEMENT: The main identified lifestyle behavior was poor physical activity, low adherence to Mediterranean Diet and high screen and sleep time. Children should increase physical activity levels, adherence to Mediterranean diet, decrease screen and sleep the appropriate hours per day. Families, schools, and medical communities must work together to gloss over present and future diseases. Sleep time had not been previously included in cluster analysis with physical activity, sedentary behaviors, obesity, and nutritional status, thus the present data open a new perspective in Spanish population. Health policies should focus on promoting physical activity, Mediterranean diet, adequate sleep and reducing screen time.


Assuntos
Exercício Físico , Estilo de Vida , Feminino , Humanos , Adolescente , Criança , Masculino , Estudos Transversais , Obesidade , Comportamento Sedentário
5.
BMC Infect Dis ; 23(1): 782, 2023 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-37946107

RESUMO

BACKGROUND: Parasitological investigation of bone marrow, splenic or lymph node aspirations is the gold standard for the diagnosis of visceral leishmaniasis (VL). However, this invasive test requires skilled clinical and laboratory staff and adequate facilities, and sensitivity varies depending on the tissue used. The direct agglutination test (DAT) is a serological test that does not need specialised staff, with just minimal training required. While previous meta-analysis has shown DAT to have high sensitivity and specificity when using parasitology as the reference test for diagnosis, meta-analysis of DAT compared to other diagnostic techniques, such as PCR and ELISA, that are increasingly used in clinical and research settings, has not been done. METHODS: We conducted a systematic review to determine the diagnostic performance of DAT compared to all available tests for the laboratory diagnosis of human VL. We searched electronic databases including Medline, Embase, Global Health, Scopus, WoS Science Citation Index, Wiley Cochrane Central Register of Controlled Trials, Africa-Wide Information, LILACS and WHO Global Index. Three independent reviewers screened reports and extracted data from eligible studies. A meta-analysis estimated the diagnostic sensitivity and specificity of DAT. RESULTS: Of 987 titles screened, 358 were selected for full data extraction and 78 were included in the analysis, reporting on 32,822 participants from 19 countries. Studies included were conducted between 1987-2020. Meta-analysis of studies using serum and DAT compared to any other test showed pooled sensitivity of 95% (95%CrI 90-98%) and pooled specificity of 95% (95%CrI 88-98%). Results were similar for freeze-dried DAT and liquid DAT when analysed separately. Sensitivity was lower for HIV-positive patients (90%, CrI 59-98%) and specificity was lower for symptomatic patients (70%, CrI 43-89%). When comparing different geographical regions, the lowest median sensitivity (89%, CrI 67-97%) was in Western Asia (five studies). CONCLUSIONS: This systematic review and meta-analysis demonstrates high estimated pooled sensitivity and specificity of DAT for diagnosis of VL, although sensitivity and specificity were lower for different patient groups and geographical locations. This review highlights the lack of standardisation of DAT methods and preparations, and the lack of data from some important geographical locations. Future well-reported studies could provide better evidence to inform test implementation for different patient populations and use cases. PROSPERO REGISTRATION: CRD42021240830.


Assuntos
Soropositividade para HIV , Leishmaniose Visceral , Humanos , Leishmaniose Visceral/diagnóstico , Leishmaniose Visceral/parasitologia , Testes de Aglutinação/métodos , Testes Sorológicos/métodos , Sensibilidade e Especificidade
6.
Neurosurg Rev ; 46(1): 244, 2023 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-37707587

RESUMO

Collet-Sicard syndrome (CSS) is the unilateral palsy of the cranial nerves (CN) IX, X, XI, and XII. To our knowledge, no review describes the characteristics of patients diagnosed with CSS. Therefore, this review aims to collect and describe all cases in the literature labeled as CSS. We performed a scoping review of the literature and conducted a database search in Embase and PubMed. We included articles and abstracts with case reports or case series of patients with CSS diagnosis. We classified the cases into two groups: "CSS", referring to patients presenting exclusively with IX-XII nerve involvement, and "CSS-plus", which corresponds to cases with CSS and other neurological impairments. We included 135 patients from 126 articles, of which 84 (67.7%) were male. The most common clinical manifestations reported were dysphagia and dysphonia. The most common etiology was tumoral in 53 cases (39.6%) and vascular in 37 cases (27.6%). The majority of patients showed partial or total improvement, with just over half receiving conservative treatment. The most frequent anatomic space was the jugular foramen (44.4%) and the parapharyngeal retrostyloid space (28.9%). Approximately 21% of the patients had other CN impairments, with the seventh and eighth CN most frequently compromised. We conclude that although there is a need for greater rigor in CSS reporting, the syndrome has a clear utility in identifying the localization of jugular foramen and parapharyngeal retrostyloid space pathology.


Assuntos
Transtornos de Deglutição , Doenças do Nervo Glossofaríngeo , Humanos , Masculino , Feminino , Nervo Glossofaríngeo , Tratamento Conservador , Bases de Dados Factuais , Transtornos de Deglutição/etiologia
7.
J Biol Chem ; 296: 100341, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33515545

RESUMO

Gene duplication generates new functions and traits, enabling evolution. Human-specific duplicated genes in particular are primary sources of innovation during our evolution although they have very few known functions. Here we examine the brain function of one of these genes (CHRFAM7A) and its product (dupα7 subunit). This gene results from a partial duplication of the ancestral CHRNA7 gene encoding the α7 subunit that forms the homopentameric α7 nicotinic acetylcholine receptor (α7-nAChR). The functions of α7-nAChR in the brain are well defined, including the modulation of synaptic transmission and plasticity underlying normal attention, cognition, learning, and memory processes. However, the role of the dupα7 subunit remains unexplored at the neuronal level. Here, we characterize that role by combining immunoblotting, quantitative RT-PCR and FRET techniques with functional assays of α7-nAChR activity using human neuroblastoma SH-SY5Y cell variants with different dupα7 expression levels. Our findings reveal a physical interaction between dupα7 and α7 subunits in fluorescent protein-tagged dupα7/α7 transfected cells that negatively affects normal α7-nAChR activity. Specifically, in both single cells and cell populations, the [Ca2+]i signal and the exocytotic response induced by selective stimulation of α7-nAChR were either significantly inhibited by stable dupα7 overexpression or augmented after silencing dupα7 gene expression with specific siRNAs. These findings identify a new role for the dupα7 subunit as a negative regulator of α7-nAChR-mediated control of exocytotic neurotransmitter release. If this effect is excessive, it would result in an impaired synaptic transmission that could underlie the neurocognitive and neuropsychiatric disorders associated with α7-nAChR dysfunction.


Assuntos
Neurônios/metabolismo , Neurotransmissores/metabolismo , Receptor Nicotínico de Acetilcolina alfa7/metabolismo , Sinalização do Cálcio , Linhagem Celular Tumoral , Exocitose , Humanos , Receptores Nicotínicos/genética , Receptores Nicotínicos/metabolismo , Regulação para Cima , Receptor Nicotínico de Acetilcolina alfa7/genética
8.
Chembiochem ; 23(7): e202100393, 2022 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-34529328

RESUMO

Specific S477N, N501Y, K417N, K417T, E484K mutations in the receptor binding domain (RBD) of the spike protein in the wild type SARS-COV-2 virus have resulted, among others, in the following variants: B.1.160 (20A or EU2, first reported in continental Europe), B1.1.7 (α or 20I501Y.V1, first reported in the United Kingdom), B.1.351 (ß or 20H/501Y.V2, first reported in South Africa), B.1.1.28.1 (γ or P.1 or 20J/501Y.V3, first reported in Brazil), and B.1.1.28.2 (ζ, or P.2 or 20B/S484K, also first reported in Brazil). From the analysis of a set of bonding descriptors firmly rooted in the formalism of quantum mechanics, including Natural Bond Orbitals (NBO), Quantum Theory of Atoms In Molecules (QTAIM) and highly correlated energies within the Domain Based Local Pair Natural Orbital Coupled Cluster Method (DLPNO-CCSD(T)), and from a set of computed electronic spectral patterns with environmental effects, we show that the new variants improve their ability to recognize available sites to either hydrogen bond or to form salt bridges with residues in the ACE2 receptor of the host cells. This results in significantly improved initial virus⋅⋅⋅cell molecular recognition and attachment at the microscopic level, which trigger the infectious cycle.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Mutação , Ligação Proteica/genética , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/química
9.
Chembiochem ; 23(21): e202200351, 2022 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-35951472

RESUMO

The zika virus (ZIKV), transmitted to humans from the bites of Aedes Aegypti and Aedes Albopictus mosquitoes produces Zika fever and neurodegenerative disorders that despite affecting millions of people, most recently in Africa and the Americas, has been declared a neglected tropical disease by the World Health Organization. In this work, atomistic molecular dynamics simulations followed by rigorous analysis of the intermolecular interactions reveal crucial aspects of the initial virus⋯cell molecular recognition and attachment, events that trigger the infectious cycle. Previous experimental studies have shown that Dermatan Sulfate (DS) and Chondroitin Sulfate A (CSA), two glycosaminoglycans which are actually epimers to each other and that are structural constituents of receptors expressed in cell membranes, are the preferred anchorage sites, with a marked preference for DS. Our calculations rationalize this preference from a molecular perspective as follows: when free of the virus, DS has one sulfate group that does not participate in intramolecular strong hydrogen bonds, thus, it is readily available to interact with the envelope protein of the virus (Zika-E), then, after formation of the complexes, Zika-E⋯DS exhibits ten strong salt brides connecting the two fragments against only six salt bridges and two hydrogen bonds in Zika-E⋯CSA. Our results complement the current view of the interaction between the virus and the receptor glycosoaminoglycans revealing that the negatively charged carboxylate groups in CSA and DS are just as important as the sulfates because of the formation of equally strong salt bridges with the positively charged Arginine and Lysine aminoacids in the envelope protein of the virus.


Assuntos
Aedes , Infecção por Zika virus , Zika virus , Animais , Humanos , Zika virus/metabolismo , Simulação de Dinâmica Molecular , Aedes/metabolismo , Glicosaminoglicanos
10.
Environ Res ; 214(Pt 3): 113996, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35926576

RESUMO

PURPOSE: The aim of this study was to analyse the relationship between air pollution and 24-h movement guidelines in Spanish children/adolescents. METHODS: This cross-sectional study analysed secondary data from the Encuesta Nacional de Salud Española (2017), a representative survey for the Spanish population. The original dataset included 6016 Spanish young people (aged 0-14 years). Since the data on 24-h movement recommendations were limited to Spanish young people aged 2-14 years, the final sample included 4398 (49.2% girls) Spanish young people. Air pollution was evaluated by particulate matter 2.5 (PM2.5) from different Spanish regions and divided into tertiles representing areas with low, medium, and high pollution. Sleep duration and recreational screen time and were reported by the parents/caregivers. Physical activity was evaluated by an adapted version of the International Physical Activity Questionnaire. Time spent in screen time, sleep, and physical activity were classified as meeting or not the 24-h movement guidelines. RESULTS: After adjusting for several covariates (sex, age, immigrant status, region, socioeconomic status, and body mass index), lower odds of meeting with the 24-h movement recommendations were found in those living in areas with medium (odds ratio [OR] = 0.55; confident interval [CI] 95%, 0.46-0.67) or high air pollution (OR = 0.45; CI 95%, 0.36-0.55), compared with those living in areas with low air pollution. CONCLUSIONS: The movement behaviour of young people seems to be associated with the presence of air pollution among Spanish youth. Spanish public health agencies could consider the development of strategies to mitigate the health risks for children/adolescents in high air polluted areas.


Assuntos
Poluição do Ar , Comportamento Sedentário , Adolescente , Criança , Estudos Transversais , Exercício Físico , Feminino , Humanos , Masculino , Tempo de Tela , Sono
11.
Molecules ; 27(24)2022 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-36557799

RESUMO

Neutral (n) and zwitterionic (z) forms of cysteine monomers are combined in this work to extensively explore the potential energy surfaces for the formation of cysteine dimers in aqueous environments represented by a continuum. A simulated annealing search followed by optimization and characterization of the candidate structures afforded a total of 746 structurally different dimers held together via 80 different types of intermolecular contacts in 2894 individual non-covalent interactions as concluded from Natural Bond Orbitals (NBO), Quantum Theory of Atoms in Molecules (QTAIM) and Non-Covalent Interactions (NCI) analyses. This large pool of interaction possibilities includes the traditional primary hydrogen bonds and salt bridges which actually dictate the structures of the dimers, as well as the less common secondary hydrogen bonds, exotic X⋯Y (X = C, N, O, S) contacts, and H⋯H dihydrogen bonds. These interactions are not homogeneous but have rather complex distributions of strengths, interfragment distances and overall stabilities. Judging by their Gibbs bonding energies, most of the structures located here are suitable for experimental detection at room conditions.


Assuntos
Cisteína , Teoria Quântica , Polímeros , Ligação de Hidrogênio
12.
Water Sci Technol ; 86(1): 211-226, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35838292

RESUMO

Microalgae wastewater treatment systems have the potential for producing added-value products. More specifically, cyanobacteria are able to accumulate polyhydroxybutyrates (PHBs), which can be extracted and used for bioplastics production. Nonetheless, PHB production requires proper culture conditions and continue monitoring, challenging the state-of-the-art technologies. The aim of this study was to investigate the application of hyperspectral technologies to monitor cyanobacteria population growth and PHB production. We have established a ground-breaking measurement method able to discern spectral reflectance changes from light emitted to cyanobacteria in different phases. All in all, enabling to distinguish between cyanobacteria growth phase and PHB accumulation phase. Furthermore, first tests of classification algorithms used for machine learning and image recognition technologies had been applied to automatically recognize the different cyanobacteria species from a complex microbial community containing cyanobacteria and microalgae cultivated in pilot-scale photobioreactors (PBRs). We have defined three main indicators for monitoring PHB production: (i) cyanobacteria specific-strain density, (ii) differentiate between growth and PHB-accumulation and (iii) chlorosis progression. The results presented in this study represent an interesting alternative for traditional measurements in cyanobacteria PHB production and its application in pilot-scale PBRs. Although not directly determining the amount of PHB production, they would give insights on the undergoing processes.


Assuntos
Hidroxibutiratos , Análise Espectral , Synechocystis , Hidroxibutiratos/metabolismo , Fotobiorreatores , Poliésteres , Synechocystis/metabolismo
13.
Rev Esp Enferm Dig ; 114(4): 247-258, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35000402

RESUMO

Male, 24 yo, obesity class 1. We place him a 6 month intragastric balloon. He keeps asymptomatic while taking PPIs, having lost 13 kg in 4 months. He starts on month 5 with epigastric pain, just after abandoning omeprazole on his own. The pain worsens in spite of restarting PPIs and we schedule an urgent retrieval of the balloon. Gastric ulcer perforation occurs during balloon removal and the patient is operated.


Assuntos
Balão Gástrico , Úlcera Gástrica , Dor Abdominal/etiologia , Balão Gástrico/efeitos adversos , Humanos , Masculino , Omeprazol/uso terapêutico , Inibidores da Bomba de Prótons/uso terapêutico , Úlcera Gástrica/etiologia , Adulto Jovem
14.
Cell Physiol Biochem ; 55(1): 17-32, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33443845

RESUMO

BACKGROUND/AIMS: Microglia are the dynamic motile phagocytes of the brain considered the first line of defense against threats or disturbances to the Central Nervous System (CNS). Microglia help orchestrate the immunological response by interacting with others immune cells. Mast cells (MCs) are effector cells of the innate immune system distributed in all organs and vascularized tissues, brain included. Several molecular mechanisms for potential interactions between MCs and microglia have been determined. However, the effect of MCs on regulated exocytosis and phagocytic clearance in microglia has not been explored. METHODS: Cocktails of MCs mediators (MCM) obtained at 37°C and 53°C were used to induce microglia activation. Changes in intracellular calcium [Ca2+]i and ATP release were studied by calcium and quinacrine fluorescence imaging. Fluorescent latex beads were used to assay phagocytosis in microglia after MCM treatment and compared to that measured in the presence of histamine, ATP and lipopolysaccharide (LPS). Iba-1 expression and area were quantified by immunofluorescence and histamine levels evaluated by ELISA techniques. RESULTS: Local application onto microglia of the MC mediator cocktail elicited Ca2+ transients and exocytotic release associated with quinacrine dye de-staining. Ca2+ signals were mimicked by histamine and blocked by the H1 receptor (H1R) antagonist, cetirizine. Hydrolysis of ATP by apyrase also affected Ca2+ transients to a lesser extent. Iba-1 fluorescence, cell area and phagocytosis were enhanced by histamine through H1R. However, ATP prevented iba-1 expression and microglial phagocytosis. MCM showed combined effects of histamine and ATP, increasing the number of internalized microbeads per cell and area without raising iba1 expression. CONCLUSION: Our results highlight the relevance of MC-derived histamine and ATP in the modulation of secretory and phagocytic activities that would explain the heterogeneity of microglial responses in different pathological contexts.


Assuntos
Trifosfato de Adenosina/metabolismo , Sinalização do Cálcio , Comunicação Celular , Histamina/metabolismo , Mastócitos/metabolismo , Microglia/metabolismo , Animais , Ratos , Ratos Wistar
15.
Chembiochem ; 22(4): 724-732, 2021 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-32986926

RESUMO

The magnified infectious power of the SARS-CoV-2 virus compared to its precursor SARS-CoV is intimately linked to an enhanced ability in the mutated virus to find available hydrogen-bond sites in the host cells. This characteristic is acquired during virus evolution because of the selective pressure exerted at the molecular level. We pinpoint the specific residue (in the virus) to residue (in the cell) contacts during the initial recognition and binding and show that the virus⋅⋅⋅cell interaction is mainly due to an extensive network of hydrogen bonds and to a large surface of noncovalent interactions. In addition to the formal quantum characterization of bonding interactions, computation of absorption spectra for the specific virus⋅⋅⋅cell interacting residues yields significant shifts of Δλmax =47 and 66 nm in the wavelength for maximum absorption in the complex with respect to the isolated host and virus, respectively.


Assuntos
Enzima de Conversão de Angiotensina 2/metabolismo , COVID-19/prevenção & controle , Receptores Virais/metabolismo , SARS-CoV-2/metabolismo , Glicoproteína da Espícula de Coronavírus/metabolismo , Sequência de Aminoácidos , Enzima de Conversão de Angiotensina 2/química , Enzima de Conversão de Angiotensina 2/genética , COVID-19/epidemiologia , COVID-19/virologia , Humanos , Simulação de Dinâmica Molecular , Pandemias , Ligação Proteica , Domínios Proteicos , Receptores Virais/química , Receptores Virais/genética , SARS-CoV-2/genética , SARS-CoV-2/fisiologia , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética
16.
Int J Behav Nutr Phys Act ; 18(1): 98, 2021 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-34274002

RESUMO

BACKGROUND: Validation of self-reported tools, such as physical activity (PA) questionnaires, is crucial. The aim of this study was to determine test-retest reliability, internal consistency, and the concurrent, construct, and predictive validity of the short semi-quantitative Physical Activity Unit 7 item Screener (PAU-7S), using accelerometry as the reference measurement. The effect of linear calibration on PAU-7S validity was tested. METHODS: A randomized sample of 321 healthy children aged 8-16 years (149 boys, 172 girls) from the nationwide representative PASOS study completed the PAU-7S before and after wearing an accelerometer for at least 7 consecutive days. Weight, height, and waist circumference were measured. Cronbach alpha was calculated for internal consistency. Test-retest reliability was determined by intra-class correlation (ICC). Concurrent validity was assessed by ICC and Spearman correlation coefficient between moderate to vigorous PA (MVPA) derived by the PAU-7S and by accelerometer. Concordance between both methods was analyzed by absolute agreement, weighted kappa, and Bland-Altman statistics. Multiple linear regression models were fitted for construct validity and predictive validity was determined by leave-one-out cross-validation. RESULTS: The PAU-7S overestimated MVPA by 18%, compared to accelerometers (106.5 ± 77.0 vs 95.2 ± 33.2 min/day, respectively). A Cronbach alpha of 0.76 showed an acceptable internal consistency of the PAU-7S. Test-retest reliability was good (ICC 0.71 p < 0.001). Spearman correlation and ICC coefficients of MVPA derived by the PAU-7S and accelerometers increased from 0.31 to 0.62 and 0.20 to 0.62, respectively, after calibration of the PAU-7S. Between-methods concordance improved from a weighted kappa of 0.24 to 0.50 after calibration. A slight reduction in ICC, from 0.62 to 0.60, yielded good predictive validity. Multiple linear regression models showed an inverse association of MVPA with standardized body mass index (ß - 0.162; p < 0.077) and waist to height ratio (ß - 0.010; p < 0.014). All validity dimensions were somewhat stronger in boys compared to girls. CONCLUSION: The PAU-7S shows a good test-retest reliability and acceptable internal consistency. All dimensions of validity increased from poor/fair to moderate/good after calibration. The PAU-7S is a valid instrument for measuring MVPA in children and adolescents. TRIAL REGISTRATION: Trial registration number ISRCTN34251612 .


Assuntos
Acelerometria , Exercício Físico , Inquéritos e Questionários/normas , Acelerometria/normas , Adolescente , Calibragem , Criança , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes , Comportamento Sedentário
17.
Philos Trans A Math Phys Eng Sci ; 379(2209): 20200346, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34510929

RESUMO

The hydrodeoxygenation (HDO) of acetophenone was evaluated in liquid phase and gas phase over monometallic Pt/SiO2, Co/SiO2 and bimetallic Pt-Co/SiO2 catalysts. The influence of reaction time and loading of the catalyst were analysed by following the conversion and products selectivity. Phenylethanol, cyclohexylethanone and cyclohexylethanol are the main products of reaction using the Pt/SiO2 catalyst. By contrast, ethylbenzene and phenylethanol are the only products formed on the Co/SiO2 and Pt-Co/SiO2 catalysts. The bimetallic catalyst is more stable as a function of time and more active towards the HDO process than the monometallic systems. The presence of an organic solvent showed only minor changes in product yields with no effect on the product speciation. Periodic density functional theory analysis indicates a stronger interaction between the carbonyl group of acetophenone with Co than with Pt sites of the mono and bimetallic systems, indicating a key activity of oxophilic sites towards improved selectivity to deoxygenated products. This article is part of the theme issue 'Bio-derived and bioinspired sustainable advanced materials for emerging technologies (part 2)'.

18.
Cereb Cortex ; 30(8): 4544-4562, 2020 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-32227119

RESUMO

Neuronal spiking activity encoding working memory (WM) is robust in primate association cortices but weak or absent in early sensory cortices. This may be linked to changes in the proportion of neuronal types across areas that influence circuits' ability to generate recurrent excitation. We recorded neuronal activity from areas middle temporal (MT), medial superior temporal (MST), and the lateral prefrontal cortex (LPFC) of monkeys performing a WM task and classified neurons as narrow (NS) and broad spiking (BS). The ratio NS/BS decreased from MT > MST > LPFC. We analyzed the Allen Institute database of ex vivo mice/human intracellular recordings to interpret our data. Our analysis suggests that NS neurons correspond to parvalbumin (PV) or somatostatin (SST) interneurons while BS neurons are pyramidal (P) cells or vasoactive intestinal peptide (VIP) interneurons. We labeled neurons in monkey tissue sections of MT/MST and LPFC and found that the proportion of PV in cortical layers 2/3 decreased, while the proportion of CR cells increased from MT/MST to LPFC. Assuming that primate CR/CB/PV cells perform similar computations as mice VIP/SST/PV cells, our results suggest that changes in the proportion of CR and PV neurons in layers 2/3 cells may favor the emergence of activity encoding WM in association areas.


Assuntos
Interneurônios/citologia , Interneurônios/fisiologia , Memória de Curto Prazo/fisiologia , Neocórtex/citologia , Neocórtex/fisiologia , Animais , Macaca mulatta , Masculino
19.
Int J Qual Health Care ; 32(5): 319-324, 2020 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-32395756

RESUMO

OBJECTIVE: To evaluate the change in compliance to thromboprophylaxis guidelines before and after the implementation of a multifaceted patient safety program. DESIGN: Longitudinal before and after study. SETTING: Teaching hospital, Hospital Universitario San Ignacio, Bogotá (Colombia). PARTICIPANTS: Adult nonsurgical hospitalized patients. INTERVENTION: A multifaceted program for the prevention of venous thromboembolic (VTE) disease among adult nonsurgical hospitalized patients. The strategies of the program included (i) update and communication of thromboprophylaxis guidelines, (ii) the implementation of risk-assessment tools in electronic medical records, (iii) nursing staff activities and (iv) education to health personnel and patients for maintenance of the program. MAIN OUTCOME MEASURE: Appropriate use of thromboprophylaxis. RESULTS: 221 and 236 patients were evaluated in the pre- and postimplementation periods, respectively. Global appropriate thromboprophylaxis prescription went from 74.66 to 82.6% (P = 0.064). Adequate thromboprophylaxis in high-risk patients did not increase significantly (77.70 vs 80.62%, P = 0.528), but a significant reduction in inappropriate thromboprophylaxis formulation in low-risk patients was found, decreasing from 20.55 to 5.26% (P = 0.005). CONCLUSIONS: Implementing a quality improvement multifaceted program improves the formulation of adequate thromboprophylaxis. Reducing the inappropriate prescription of VTE prophylaxis in patients at low risk of thrombosis can lead to a reduction in bleeding complications and a better use of economic and human resources.


Assuntos
Anticoagulantes/uso terapêutico , Fidelidade a Diretrizes , Melhoria de Qualidade , Tromboembolia Venosa/prevenção & controle , Adulto , Idoso , Colômbia , Feminino , Hospitais de Ensino , Humanos , Prescrição Inadequada/prevenção & controle , Masculino , Pessoa de Meia-Idade , Segurança do Paciente , Medição de Risco/métodos
20.
J Wound Care ; 29(LatAm sup 2): 35-39, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33054616

RESUMO

Narrative review: skin tear, laceration or skin avulsion? The current definitions for skin tear, laceration and skin avulsion do not provide a clear and evident differentiation between them in clinical practice, as their descriptions vary from author to author. Most of the literature uses these terms to refer to lacerations, but in practice, they can also mean skin avulsions, skin tears and pretibial lacerations, creating confusion among health professionals. This narrative review aims to provide the authors' views to help reach a precise definition for such terms and avoid further confusion in clinical practice.


Sinopsis: Las definiciones actuales para los términos "desgarro cutáneo" (skin tear), "laceración" (laceration) y "avulsión cutánea" (skin avulsion) no permiten diferenciar estas heridas de manera clara y evidente, ya que su descripción semiológica adquiere variabilidad de nomenclatura dependiendo de cada autor, como se comprobó a través de la revisión de la literatura médica consultada. En la mayoría de los textos, los tres términos son usados indistintamente para referirse a laceraciones pero, en la práctica clínica, se suelen referir también a avulsiones cutáneas, heridas pretibiales, heridas en colgajo, y desgarros cutáneos, lo cual suele generar confusión. El objetivo de esta revisión narrativa es proveer una opinión de expertos para llegar a una descripción precisa de dichos términos y evitar, así, confusión en la práctica clínica.


Assuntos
Avulsões Cutâneas , Lacerações , Pele/lesões , Humanos , Lacerações/terapia
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