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1.
Nature ; 592(7854): 370-375, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33854247

RESUMO

At the liquid-gas phase transition in water, the density has a discontinuity at atmospheric pressure; however, the line of these first-order transitions defined by increasing the applied pressure terminates at the critical point1, a concept ubiquitous in statistical thermodynamics2. In correlated quantum materials, it was predicted3 and then confirmed experimentally4,5 that a critical point terminates the line of Mott metal-insulator transitions, which are also first-order with a discontinuous charge carrier density. In quantum spin systems, continuous quantum phase transitions6 have been controlled by pressure7,8, applied magnetic field9,10 and disorder11, but discontinuous quantum phase transitions have received less attention. The geometrically frustrated quantum antiferromagnet SrCu2(BO3)2 constitutes a near-exact realization of the paradigmatic Shastry-Sutherland model12-14 and displays exotic phenomena including magnetization plateaus15, low-lying bound-state excitations16, anomalous thermodynamics17 and discontinuous quantum phase transitions18,19. Here we control both the pressure and the magnetic field applied to SrCu2(BO3)2 to provide evidence of critical-point physics in a pure spin system. We use high-precision specific-heat measurements to demonstrate that, as in water, the pressure-temperature phase diagram has a first-order transition line that separates phases with different local magnetic energy densities, and that terminates at an Ising critical point. We provide a quantitative explanation of our data using recently developed finite-temperature tensor-network methods17,20-22. These results further our understanding of first-order quantum phase transitions in quantum magnetism, with potential applications in materials where anisotropic spin interactions produce the topological properties23,24 that are useful for spintronic applications.

2.
Nanotechnology ; 35(19)2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38316051

RESUMO

Axially heterostructured nanowires (NWs) constitute a promising platform for advanced electronic and optoelectronic nanodevices. The presence of different materials in these NWs introduces a mismatch resulting in complex strain distributions susceptible of changing the band gap and carrier mobility. The growth of these NWs presents challenges related to the reservoir effect in the catalysts droplet that affect to the junction abruptness, and the occurrence of undesired lateral growth creating core-shell heterostructures that introduce additional strain. We present herein a cathodoluminescence (CL) analysis on axially heterostructured InP/InGaP NWs with tandem solar cell structure. The CL is complemented with micro Raman, micro photoluminescence (PL), and high resolution transmission electron microscopy measurements. The results reveal the zinc blende structure of the NWs, the presence of a thin InGaP shell around the InP bottom cell, along with its associated strain, and the doping distribution.

3.
J Oral Rehabil ; 51(2): 427-454, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37743593

RESUMO

OBJECTIVES: To evaluate the association between low back pain (LBP) and painful temporomandibular disorders (TMDs). METHODS: Systematic review of observational studies. Searches were conducted using OVID MEDLINE, CINHAL, Web of Science and PUBMED databases up to 21 October 2022. Qualitative and quantitative analyses were performed. Risk of bias (RoB) was assessed using the Quality in Prognosis Studies tool (QUIPS). RESULTS: Eight studies were included in the present review with meta-analysis. The first onset of TMDs was more likely in patients with previous chronic LBP (hazard ratio (HR) 1.53 [95% confidence interval (CI): 1.28; 1.83, p < .00001]). In addition, patients with chronic LBP had 3.25 times the odds (OR) [95% CI: 1.94; 5.43, p < .00001] of having chronic TMDs than those who did not have chronic LBP. In addition, the higher the exposure to chronic LBP, the higher the risk of developing a first onset of TMDs. CONCLUSIONS: Chronic LBP can be considered a risk/contributing factor for painful TMDs. Although there is a high certainty in the evidence linking chronic LBP with the risk of a first onset of TMDs, there are insufficient studies to draw definitive conclusions. Furthermore, while an association between chronic LBP and chronic TMDs and a dose-effect was observed between these two conditions, a limited number of studies and evidence exist to support these findings. Future studies are needed to increase the body of evidence.


Assuntos
Dor Lombar , Transtornos da Articulação Temporomandibular , Humanos , Doença Crônica , Dor Lombar/complicações , Prognóstico , Transtornos da Articulação Temporomandibular/complicações , Transtornos da Articulação Temporomandibular/epidemiologia , Estudos Observacionais como Assunto
4.
Ergonomics ; 67(1): 95-101, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37083570

RESUMO

This study investigates the differences in metabolic energy cost and physiological adaptations between carrying a suspended backpack and a traditional backpack during exercise. For that, 30 males completed the Bruce test while carrying a loaded backpack. Researchers used a metabolic system to obtain variables, analysed muscle oxygen saturation, and used a 2-way RM ANOVA. As results, a significant fatigue interaction was found, but the interaction between fatigue and backpack was non-significant. Using a suspended backpack resulted in energetic advantages in oxygen consumption, muscle oxygen saturation, and performance compared to a traditional backpack. In conclusion, this study offers insights into the physiological implications of using a suspended backpack, suggesting it may reduce the risk of musculoskeletal issues and improve performance for those carrying heavy loads.Practitioner summary: The suspended-load backpacks have been proposed as an alternative to traditional backpacks. This study highlighted that the use of a suspended backpack provided some energetical advantages adaptation compared to the traditional backpack in terms of oxygen consumption, muscle oxygen saturation and performance during a multistage treadmill test walking-running test.


Assuntos
Corrida , Caminhada , Masculino , Humanos , Suporte de Carga/fisiologia , Caminhada/fisiologia , Consumo de Oxigênio/fisiologia , Fadiga , Fenômenos Biomecânicos
5.
Actas Dermosifiliogr ; 115(4): 387-392, 2024 Apr.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-38065318

RESUMO

Communication with teenagers who are significantly affected by sexually transmitted infections (STIs) is essential for the sake of prevention. The aim of this study is to develop a specific questionnaire for surveying the degree of knowledge, behavior, and attitudes of current teenagers and young adults on STIs to come up with the proper training tools. We conducted the study following the Delphi method, a 2-round critical assessment score (from 1 to 9) of all domains and items. Only domains and items with median scores ≥8 were selected. A total of 8 panelists were involved in this survey. After establishing a median score ≥8, a total of 14 domains and 40 items were eventually selected. This is the first questionnaire ever conducted to study the knowledge, habits, and attitudes of contemporary teenagers and young adults on STIs, and stands as a valuable tool for future training on STI prevention in teenagers and young adults.


Assuntos
Comportamento Sexual , Infecções Sexualmente Transmissíveis , Humanos , Adolescente , Adulto Jovem , Conhecimentos, Atitudes e Prática em Saúde , Infecções Sexualmente Transmissíveis/epidemiologia , Infecções Sexualmente Transmissíveis/prevenção & controle , Inquéritos e Questionários , Hábitos
6.
Actas Dermosifiliogr ; 115(4): T387-T392, 2024 Apr.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-38331169

RESUMO

Communication with teenagers who are significantly affected by sexually transmitted infections (STIs) is essential for the sake of prevention. The aim of this study is to develop a specific questionnaire for surveying the degree of knowledge, behavior, and attitudes of current teenagers and young adults on STIs to come up with the proper training tools. We conducted the study following the Delphi method, a 2-round critical assessment score (from 1 to 9) of all domains and items. Only domains and items with median scores ≥8 were selected. A total of 8 panelists were involved in this survey. After establishing a median score ≥8, a total of 14 domains and 40 items were eventually selected. This is the first questionnaire ever conducted to study the knowledge, habits, and attitudes of contemporary teenagers and young adults on STIs, and stands as a valuable tool for future training on STI prevention in teenagers and young adults.


Assuntos
Comportamento Sexual , Infecções Sexualmente Transmissíveis , Humanos , Adolescente , Adulto Jovem , Conhecimentos, Atitudes e Prática em Saúde , Infecções Sexualmente Transmissíveis/epidemiologia , Infecções Sexualmente Transmissíveis/prevenção & controle , Inquéritos e Questionários , Hábitos
7.
Environ Res ; 216(Pt 4): 114773, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36379238

RESUMO

Herein electrochemical oxidation (EO) is proposed as a novel path to treat the process water obtained from hydrothermal carbonization of olive tree pruning. The aim of this work is to analyze the organic matter removal achieved by the treatment along with the identification of the chemical species formed after the electro-oxidation process at different experimental conditions. Three different tests were performed in a boron doped diamond cell, using Na2SO4 and NaCl as supporting electrolytes to compare the results obtained with the raw process water. The organic matter removal was evaluated by means of total organic carbon and chemical oxygen demand, while Gas Chromatography Mass Spectrometry was used to determine the chemical species present before and after the treatment. The addition of a promoter considerably increased the organic matter removal. In fact, the experiments performed using supporting electrolytes showed the best results in terms of organic matter removal compared to the control experiment (30-40% vs. 17%); This reduction agrees with the volatile fatty acids' measurements. Almost all the chemical species identified in the different feedstocks were partially or totally removed after the EO treatment depending on the experimental conditions. The specific energy consumption and the cost calculated for the treatment is highly dependent on the time of electro-oxidation and the supporting electrolyte used, obtaining values from 1 to 45 €/kg CODremoved. All in all, this work suggests an interesting path towards a further utilization of process water from hydrothermal carbonization processes.


Assuntos
Poluentes Químicos da Água , Água , Poluentes Químicos da Água/análise , Eletrodos , Diamante , Oxirredução , Eletrólitos/química
8.
J Endocrinol Invest ; 46(12): 2423-2443, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37454031

RESUMO

BACKGROUND: Type 2 diabetes is an increasing health problem worldwide. HIIT has been proposed as an exercise alternative to be part of integral type 2 diabetes treatment. OBJECTIVE: The aim of this meta-analysis was to determine the effect of different types of chronic HIIT on glycaemic control, aerobic resistance, and body composition in individuals above 18 years with T2D. DESIGN: This meta-analysis was conducted in accordance with the Preferred Reporting Items for Systematic Review and Meta-analysis (PRISMA) statement and was registered with PROSPERO on November 21st, 2021. DATA SOURCES: A systematic literature search of the following databases: EbscoHost (Academic Search Ultimate, Fuente Académica Plus, MEDline and SportDiscus), Web of Science, PubMed, and EMBASE between April of 2021 and April of 2023 was conducted. ELIGIBILITY CRITERIA FOR SELECTING STUDIES: Eligibility criteria included (1) participants aged ≥ 18 years with a diagnosis of type 2 diabetes, (2) an HIIT protocol with detailed description, (3) control group and/or continuous aerobic training comparison group, (4) report of pre-test and post-test values for at least one of the studied variables (from glycaemic control, aerobic resistance, and/or body composition), and (5) experimental or quasi-experimental intervention design. ANALYSES: Meta-analysis was made by a pre-post-test between-group analysis following the inverse variance heterogeneity model for each variable, and then, a subgroup analysis by type of HIIT was conducted. RESULTS: Of the 2817 records obtained, 180 records were included for meta-analysis. Significant improvements were found in the most part of the variables when HIIT was compared to control group, while fat-free mass kept without changes. HIIT vs. continuous aerobic training results showed and advantage in favor of HIIT for fasting blood glycemia. Subgroup analysis refers a possible advantage of SI-HIIT and SIT-HIIT in the improvement of fasting glycemia and SIT-HIIT advantage in HOMA 1-IR decrease. CONCLUSIONS: HIIT improves glycaemic control, aerobic resistance, and % fat and waist circumference, and kept fat-free mass unchanged in individuals with T2D. SI-HIIT and SIT-HIIT could be better than the other types of HIIT. HIIT benefit is similar to continuous aerobic training except for fasting blood glycemia.


Assuntos
Diabetes Mellitus Tipo 2 , Treinamento Intervalado de Alta Intensidade , Humanos , Treinamento Intervalado de Alta Intensidade/métodos , Diabetes Mellitus Tipo 2/terapia , Controle Glicêmico , Composição Corporal , Exercício Físico
9.
Public Health ; 215: 83-90, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36652786

RESUMO

OBJECTIVES: This paper presents a new approach based on the combination of machine learning techniques, in particular, sentiment analysis using lexicons, and multivariate statistical methods to assess the evolution of social mood through the COVID-19 vaccination process in Spain. METHODS: Analysing 41,669 Spanish tweets posted between 27 February 2020 and 31 December 2021, different sentiments were assessed using a list of Spanish words and their associations with eight basic emotions (anger, fear, anticipation, trust, surprise, sadness, joy and disgust) and three valences (neutral, negative and positive). How the different subjective emotions were distributed across the tweets was determined using several descriptive statistics; a trajectory plot representing the emotional valence vs narrative time was also included. RESULTS: The results achieved are highly illustrative of the social mood of citizens, registering the different emerging opinion clusters, gauging public states of mind via the collective valence, and detecting the prevalence of different emotions in the successive phases of the vaccination process. CONCLUSIONS: The present combination in formal models of objective and subjective information would therefore provide a more accurate vision of social reality, in this case regarding the COVID-19 vaccination process in Spain, which will enable a more effective resolution of problems.


Assuntos
COVID-19 , Mídias Sociais , Humanos , COVID-19/epidemiologia , COVID-19/prevenção & controle , Vacinas contra COVID-19 , Espanha/epidemiologia , Aprendizado de Máquina , Vacinação
10.
Med Oral Patol Oral Cir Bucal ; 28(6): e572-e580, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37099709

RESUMO

BACKGROUND: Evaluating 2-years implant loss and marginal bone loss in patients with hereditary coagulopathies, comparing with a healthy control group. MATERIAL AND METHODS: 37 implants in 13 patients (17 haemophilia A, 20 Von-Willebrand disease) versus 26 implants in 13 healthy patients. Data measured through Lagervall-Jansson index (after surgery, at prosthetic loading, at 2 years). STATISTICS: Chi-square, Haberman's, ANOVA, Mann-Whitney-U. Significance p<0.05. RESULTS: Haemorrhagic accidents in 2 coagulopathies patients (non-statistical differences). Hereditary coagulopathies patients suffered more hepatitis (p<0.05), HIV (p<0.05) and less previous periodontitis (p<0.01). Non-statistical differences in marginal bone loss among groups. 2 implants were lost in the hereditary coagulopathies and none in the control group (non-statistical differences). Hereditary coagulopathies patients had longer (p<0.001), and narrower implants (p<0.05) placed. 43.2% external prosthetic connection in hereditary coagulopathies patients (p<0.001); change of prosthetic platform more frequent in control group (p<0.05). 2 implants lost: external connection (p<0.05). Survival rate 96.8% (hereditary coagulopathies 94.6%, control group 100%). CONCLUSIONS: Implant and marginal bone loss at 2 years is similar in patients with hereditary coagulopathies and control group. Precautions should be taken on the treatment for hereditary coagulopathies patients, through prior haematological protocol. Implant loss only occurred in in a patient with Von-Willebrand´s disease.


Assuntos
Perda do Osso Alveolar , Implantes Dentários , Humanos , Implantação Dentária Endóssea/métodos , Estudos Retrospectivos , Implantes Dentários/efeitos adversos , Perda do Osso Alveolar/etiologia , Estudos de Casos e Controles , Prótese Dentária Fixada por Implante , Seguimentos , Planejamento de Prótese Dentária
11.
Radiologia ; 65(3): 222-229, 2023.
Artigo em Espanhol | MEDLINE | ID: mdl-36193234

RESUMO

Background and aims: To analyze the diagnostic performance of pulmonary CT angiography and to compare different D-dimer cutoffs for the diagnosis of acute pulmonary embolism in patients with and without SARS-CoV-2 infections. Materials and methods: We retrospectively analyzed all consecutive pulmonary CT angiography studies done for suspected pulmonary embolism in a tertiary hospital during two time periods: the first December 2020 through February 2021 and the second December 2017 through February 2018. D-dimer levels were obtained less than 24 hours before the pulmonary CT angiography studies. We analyzed the sensitivity, specificity, positive and negative predictive values, area under the receiver operating curve (AUC), and pattern of pulmonary embolism for six different values of D-dimer and the extent of the embolism. During the pandemic period, we also analyzed whether the patients had COVID-19. Results: After excluding 29 poor-quality studies, 492 studies were analyzed; 352 of these were done during the pandemic, 180 in patients with COVID-19 and 172 in patients without COVID-19. The absolute frequency of pulmonary embolism diagnosed was higher during the pandemic period (34 cases during the prior period and 85 during the pandemic; 47 of these patients had COVID-19). No significant differences were found in comparing the AUCs for the D-dimer values. The optimum values calculated for the receiver operating characteristic curves differed between patients with COVID-19 (2200 mcg/L), without COVID-19 (4800 mcg/L), and diagnosed in the prepandemic period (3200 mcg/L). Peripheral distribution of the emboli was more common in patients with COVID-19 (72%) than in those without COVID-19 and than in those diagnosed before the pandemic [OR 6.6, 95% CI:1.5?24.6, p< 0.05 when compared to central distribution]. Conclusions: The number of CT angiography studies and the number of pulmonary embolisms diagnosed during the pandemic increased due to SARS-CoV-2 infection. The optimal D-dimer cutoffs and the distribution of the pulmonary embolisms differed between the groups of patients with and without COVID-19.

12.
Environ Sci Technol ; 56(2): 1125-1137, 2022 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-34985868

RESUMO

Some infectious diseases, including COVID-19, can undergo airborne transmission. This may happen at close proximity, but as time indoors increases, infections can occur in shared room air despite distancing. We propose two indicators of infection risk for this situation, that is, relative risk parameter (Hr) and risk parameter (H). They combine the key factors that control airborne disease transmission indoors: virus-containing aerosol generation rate, breathing flow rate, masking and its quality, ventilation and aerosol-removal rates, number of occupants, and duration of exposure. COVID-19 outbreaks show a clear trend that is consistent with airborne infection and enable recommendations to minimize transmission risk. Transmission in typical prepandemic indoor spaces is highly sensitive to mitigation efforts. Previous outbreaks of measles, influenza, and tuberculosis were also assessed. Measles outbreaks occur at much lower risk parameter values than COVID-19, while tuberculosis outbreaks are observed at higher risk parameter values. Because both diseases are accepted as airborne, the fact that COVID-19 is less contagious than measles does not rule out airborne transmission. It is important that future outbreak reports include information on masking, ventilation and aerosol-removal rates, number of occupants, and duration of exposure, to investigate airborne transmission.


Assuntos
Poluição do Ar em Ambientes Fechados , COVID-19 , Aerossóis , Surtos de Doenças , Humanos , SARS-CoV-2 , Ventilação
13.
Res Sports Med ; 30(3): 295-307, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-33579162

RESUMO

The evolution of functional classification (FT) is important for promoting competitive balance. Technological advances allow the objective monitoring of competitive demands that is required to manage and individualize workloads. Therefore, this study aimed to characterize external workload in all matches from the 2018/2019 season of the CPF7 Spanish National League and to compare demands based on the new FT (FT1, FT2 yFT3) in time-motion (locomotion and speed changes) and accelerometer-based workload (impacts). Statistical analysis was composed of one-way ANOVA with Bonferroni post-hoc and omega partial squared effect size. Differences were found among all FT in total distance, running, high-intensity, sprinting, very high accelerations and decelerations (FT3> FT2> FT1; p < .01; ωp2= 0.29-to-0.43); and with respect to the highest functional limitation (FT3 = FT2> FT1) in maximum sprinting, moderate-high accelerations and decelerations, total impacts and at very-low intensity (ωp2= 0.13-to-0.29). In conclusion, FT3 players presented a physical advantage with respect to FT2-FT1 players in competition, especially in high-intensity actions that are crucial in team-sports performance. The present results facilitate designing specific training workloads according to FT, players' disability and competition demands, being the first approach to characterize match demands with inertial devices based on the new FT.


Assuntos
Desempenho Atlético , Paralisia Cerebral , Futebol Americano , Futebol , Humanos , Estações do Ano , Carga de Trabalho
14.
Bioinformatics ; 36(19): 4827-4832, 2020 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-32614398

RESUMO

MOTIVATION: Short bioactive peptides encoded by small open reading frames (sORFs) play important roles in eukaryotes. Bioinformatics prediction of ORFs is an early step in a genome sequence analysis, but sORFs encoding short peptides, often using non-AUG initiation codons, are not easily discriminated from false ORFs occurring by chance. RESULTS: AnABlast is a computational tool designed to highlight putative protein-coding regions in genomic DNA sequences. This protein-coding finder is independent of ORF length and reading frame shifts, thus making of AnABlast a potentially useful tool to predict sORFs. Using this algorithm, here, we report the identification of 82 putative new intergenic sORFs in the Caenorhabditis elegans genome. Sequence similarity, motif presence, expression data and RNA interference experiments support that the underlined sORFs likely encode functional peptides, encouraging the use of AnABlast as a new approach for the accurate prediction of intergenic sORFs in annotated eukaryotic genomes. AVAILABILITY AND IMPLEMENTATION: AnABlast is freely available at http://www.bioinfocabd.upo.es/ab/. The C.elegans genome browser with AnABlast results, annotated genes and all data used in this study is available at http://www.bioinfocabd.upo.es/celegans. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Assuntos
Caenorhabditis elegans , Biologia Computacional , Animais , Caenorhabditis elegans/genética , Genoma , Fases de Leitura Aberta , Software
15.
Int J Med Microbiol ; 311(1): 151471, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33373839

RESUMO

Staphylococcus aureus colonization increases the risk of invasive infections in different groups of patients. We analyzed the dynamics and factors associated with S. aureus colonization in hemodialysis patients. A longitudinal study was conducted at a dialysis center associated with a tertiary health care institution. S. aureus colonization was assessed three times in nostrils and on the skin and was classified as absent, intermittent or persistent. The molecular analysis included pulsed-field gel electrophoresis (PFGE) and spa-typing. Clonal complex was inferred from spa-typing. A model of generalized estimating equations was performed to determine the factors associated with colonization. A total of 210 patients were included. Colonization by methicillin-susceptible (MSSA) and methicillin-resistant (MRSA) isolates was 29.1 % vs. 4.8 %, 29.2 % vs. 6.7 % and 24.1 % vs. 7.1 % in the first, second and third screenings respectively. Most of the colonized patients were intermittent carriers (77.8 %, n = 63). PFGE and spa-typing revealed a high genetic diversity. One third (33.3 %) of the carriers classified as persistent had different clones during follow-up. Clonal complex 8 was frequent among MSSA (28 %) and MRSA (59 %) isolates. Current smoking (OR:7.22, 95 %CI 2.24-23.27), Charlson index (OR:1.22, 95 %CI 1.03-1.43) and previous infection by S. aureus (OR:2.41; 95 %CI:1.09-5.30) were associated with colonization by this microorganism. Colonization increased the risk of bacteremia (HR = 4.9; 95 % CI: 1.9-12.9). In conclusion, the colonization by S. aureus in hemodialysis patients changes over time and acquisition of new clones is a frequent event. These results evidence that patients are repeatedly recolonizing from hospitals, dialysis units and their homes. On the other hand, factors not associated with healthcare, as smoking, can increase the risk of colonization.


Assuntos
Variação Genética , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/genética , Humanos , Estudos Longitudinais , Diálise Renal , Infecções Estafilocócicas/epidemiologia
16.
J Nanobiotechnology ; 19(1): 65, 2021 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-33658029

RESUMO

BACKGROUND: Human cytomegalovirus (HCMV) is a worldwide infection, causing different troublesome in immunosupressed patients and very related to Human Immunodeficiency Virus 1 (HIV-1) infection, mainly in developing countries, with a co-infection rate of 80% in Africa. The high cost of present treatments and the lack of routinely tests in these countries urge the necessity to develop new molecules or strategies against HCMV. The new treatments should be low-cost and capable of avoiding the emerging problem of resistant virus. Nanoparticles play an important role in several viral infections. Our main focus is to study the potential activity of polyanionic carbosilane dendrimers (PDC), which are hyperbranched molecules with several sulfonate or sulfate groups in their periphery, against different viruses. RESULTS: We studied the activity of G1-S4, G2-S16 and G2-S24P PDCs in MRC-5 cell line against HCMV infection by several plaque reduction assays. Our results show that dendrimers present good biocompatibility at the concentrations tested (1-50 µM) for 6 days in cell culture. Interestingly, both G2-S16 and G2-S24P showed a remarked inhibition at 10 µM against HCMV infection. Results on attachment and virucidal assays indicated that the inhibition was not directed to the virus or the virus-cell attachment. However, results of time of addition, showed a longer lasting activity of these dendrimers in comparison to ganciclovir, and the combination of G2-S16 or G2-S24P with ganciclovir increases the HCMV inhibition around 90 %. CONCLUSIONS: Nanotechnology, in particular polyanionic carbosilane dendrimers, have proved their potential application against HCMV, being capable of inhibiting the infection by themselves or enhancing the activity of ganciclovir, the actual treatment. These compounds represent a low-cost approach to fight HCMV infections.


Assuntos
Antivirais/farmacologia , Infecções por Citomegalovirus/tratamento farmacológico , Citomegalovirus/efeitos dos fármacos , Dendrímeros/farmacologia , Nanotecnologia/métodos , Silanos/farmacologia , Fármacos Anti-HIV/farmacologia , Linhagem Celular , Fibroblastos , Ganciclovir , Infecções por HIV , HIV-1 , Humanos , Polieletrólitos
17.
J Nanobiotechnology ; 19(1): 158, 2021 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-34049570

RESUMO

BACKGROUND: The appearance of resistance against new treatments and the fact that HIV-1 can infect various cell types and develop reservoirs and sanctuaries makes it necessary to develop new therapeutic approaches to overcome those failures. RESULTS: Studies of cytotoxicity, genotoxicity, complexes formation, stability, resistance, release and particle size distribution confirmed that G2-SN15-PEG, G3-SN31-PEG, G2-SN15-PEG-FITC and G3-SN31-PEG-FITC dendrimers can form complexes with miRNAs being biocompatible, stable and conferring protection to these nucleic acids. Confocal microscopy and flow cytometry showed effective delivery of these four dendrimers into the target cells, confirming their applicability as delivery systems. Dendriplexes formed with the dendrimers and miRNAs significantly inhibited HIV-1 infection in PBMCs. CONCLUSIONS: These dendrimers are efficient delivery systems for miRNAs and they specifically and significantly improved the anti-R5-HIV-1 activity of these RNA molecules.


Assuntos
Cátions/farmacologia , Dendrímeros/farmacologia , Infecções por HIV/tratamento farmacológico , MicroRNAs/farmacologia , Polietilenoglicóis/farmacologia , Linhagem Celular , Sistemas de Liberação de Medicamentos , HIV-1/efeitos dos fármacos , Humanos , Leucócitos Mononucleares , Ácidos Nucleicos , Tamanho da Partícula
18.
J Res Natl Inst Stand Technol ; 126: 126040, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-36475078

RESUMO

We describe the results of a bilateral measurement comparison of optical fiber time delay between the National Institute of Standards and Technology (NIST, USA) and Laboratorio de Metrología, Instituto Costarricense de Electricidad (LAMETRO-ICE, Costa Rica), which was conducted on a single-mode optical fiber reference spool at wavelengths of 1310 nm and 1550 nm. The measurement results showed the largest difference to be less than 0.93 ns, which is within the combined standard uncertainty (coverage factor k = 1) for the measurement systems at the two laboratories.

19.
Ergonomics ; 64(2): 253-258, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32985361

RESUMO

Although school trolleys are an alternative to traditional backpacks, no studies have determined their suitability for children of different heights. This study aims to analyse the fit of a school trolley (0.89 m height from the top to the bottom of the handle) for children with different heights based on kinematic variables and the rate of perceived effort (RPE). A 3D motion capture system was used to analyse the kinematics of the thorax and hip during walking without load and when pulling a trolley loaded with 15% of the child's body weight (BW). The RPE was recorded at the end of each trial. The height of the subjects was clustered using Ward´s hierarchical cluster, and two groups were identified: Group 1: 120-139.9 cm; and Group 2: 140-160 cm. No differences were found between groups in the kinematics or RPE. In conclusion, a standard school trolley fits well to children with heights from 120 to 160 cm. Practitioner Summary: No studies have determined the suitability of school trolleys for children of different heights. This study aims to analyse the fit of a school trolley for children with different heights based on the kinematics and rate of perceived effort. The major finding is that a standard school trolley fits children with heights from 120 to 160 cm well and that the height of the school trolley was between 59% and 68% of the children's heights. Abbreviations: RPE: rate of perceived exertion; BW: body weight; CAST: calibrated anatomical system technique; GC: gait cycle.


Assuntos
Estatura/fisiologia , Instituições Acadêmicas , Caminhada/fisiologia , Suporte de Carga/fisiologia , Fenômenos Biomecânicos , Criança , Feminino , Quadril/fisiologia , Humanos , Masculino , Jogos e Brinquedos , Tórax/fisiologia
20.
Inf Fusion ; 76: 157-167, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34867127

RESUMO

The purpose of this paper is to implement a computer-aided diagnosis (CAD) system for multiple sclerosis (MS) based on analysing the outer retina as assessed by multifocal electroretinograms (mfERGs). MfERG recordings taken with the RETI-port/scan 21 (Roland Consult) device from 15 eyes of patients diagnosed with incipient relapsing-remitting MS and without prior optic neuritis, and from 6 eyes of control subjects, are selected. The mfERG recordings are grouped (whole macular visual field, five rings, and four quadrants). For each group, the correlation with a normative database of adaptively filtered signals, based on empirical model decomposition (EMD) and three features from the continuous wavelet transform (CWT) domain, are obtained. Of the initial 40 features, the 4 most relevant are selected in two stages: a) using a filter method and b) using a wrapper-feature selection method. The Support Vector Machine (SVM) is used as a classifier. With the optimal CAD configuration, a Matthews correlation coefficient value of 0.89 (accuracy = 0.95, specificity = 1.0 and sensitivity = 0.93) is obtained. This study identified an outer retina dysfunction in patients with recent MS by analysing the outer retina responses in the mfERG and employing an SVM as a classifier. In conclusion, a promising new electrophysiological-biomarker method based on feature fusion for MS diagnosis was identified.

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