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1.
J R Soc Interface ; 21(218): 20240279, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39257282

RESUMEN

Bioelectronic bone implants are being widely recognized as a promising technology for highly personalized bone/implant interface sensing and biophysical therapeutic stimulation. Such bioelectronic devices are based on an innovative concept with the ability to be applied to a wide range of implants, including in fixation and prosthetic systems. Recently, biointerface sensing using capacitive patterns was proposed to overcome the limitations of standard imaging technologies and other non-imaging technologies; moreover, electric stimulation using capacitive patterns was proposed to overcome the limitations of non-instrumented implants. We here provide an innovative low-power miniaturized electronic system with ability to provide both therapeutic stimulation and bone/implant interface monitoring using network-architectured capacitive interdigitated patterns. It comprises five modules: sensing, electric stimulation, processing, communication and power management. This technology was validated using in vitro tests: concerning the sensing system, its ability to detect biointerface changes ranging from tiny to severe bone-implant interface changes in target regions was validated; concerning the stimulation system, its ability to significantly enhance bone cells' full differentiation, including matrix maturation and mineralization, was also confirmed. This work provides an impactful contribution and paves the way for the development of the new generation of orthopaedic biodevices.


Asunto(s)
Técnicas Biosensibles , Técnicas Biosensibles/instrumentación , Humanos , Estimulación Eléctrica , Prótesis e Implantes , Interfase Hueso-Implante/fisiología , Animales
2.
Sci Adv ; 10(37): eadq4077, 2024 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-39259783

RESUMEN

We present the systematic exploration of various potential energy surfaces for systems with C6H6-x (x = 0, 1, 2, or 3) empirical formula using an automatic search approach. The primary objective of this study is to identify reaction pathways that lead to the creation of benzene, o-benzyne, and other rings. These pathways initiate with a barrierless recombination reaction and involve subsequent isomerization reactions with submerged transition states until the final product is reached. The reported reaction profiles are consistent with the existing conditions in the interstellar medium if the hot complex formed can cool down through radiative relaxation. Recent studies on the deactivation of polyaromatic hydrocarbons (PAHs) support the possibility of these reactions taking place. The C6-membered rings are considered precursors of PAHs, and our focus is on identifying pathways originating from the barrierless recombination of reactive molecules known to exist in the interstellar medium, with potential implications in other environments.

3.
Langmuir ; 2024 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-39269030

RESUMEN

Continuous particle focusing by using microfluidics is an effective method for separating particles, cells, or droplets for analytical purposes. Previously, it was shown that an alternating current across rectangular microchannels with slightly deformed side walls results in vortex flow patterns caused by alternating current electroosmosis (AC-EOF) and could lead to particle focusing. In this work, we explore this mechanism by experimentally studying the particle focusing behavior for various fluid flow velocities through a microchannel. Since it is unlikely that the particles are kept in their focused position solely by convection, a theoretical force balance between the hydrodynamic and the induced dipole force was determined. In our experiments, it was found that there is no substantial effect of the pressure-driven fluid velocity on the particle focusing velocity within the studied range. From the theoretical force balance calculations, it was determined that while the addition of the induced dipole force can still not completely describe the experimentally observed particle focusing, the induced dipole can be strong enough to overcome the hydrodynamic force. Finally, it is hypothesized that under specific circumstances, including a repulsive electrostatic force between a particle and electrode wall can complete the theoretical particle focusing force balance. Alternative phenomena that could also play a role in particle focusing are proposed.

4.
Sci Rep ; 14(1): 18991, 2024 08 16.
Artículo en Inglés | MEDLINE | ID: mdl-39152187

RESUMEN

TB/HIV coinfection poses a complex public health challenge. Accurate forecasting of future trends is essential for efficient resource allocation and intervention strategy development. This study compares classical statistical and machine learning models to predict TB/HIV coinfection cases stratified by gender and the general populations. We analyzed time series data using exponential smoothing and ARIMA to establish the baseline trend and seasonality. Subsequently, machine learning models (SVR, XGBoost, LSTM, CNN, GRU, CNN-GRU, and CNN-LSTM) were employed to capture the complex dynamics and inherent non-linearities of TB/HIV coinfection data. Performance metrics (MSE, MAE, sMAPE) and the Diebold-Mariano test were used to evaluate the model performance. Results revealed that Deep Learning models, particularly Bidirectional LSTM and CNN-LSTM, significantly outperformed classical methods. This demonstrates the effectiveness of Deep Learning for modeling TB/HIV coinfection time series and generating more accurate forecasts.


Asunto(s)
Coinfección , Predicción , Infecciones por VIH , Aprendizaje Automático , Tuberculosis , Humanos , Infecciones por VIH/complicaciones , Infecciones por VIH/epidemiología , Coinfección/epidemiología , Tuberculosis/epidemiología , Tuberculosis/complicaciones , Predicción/métodos , Femenino , Masculino , Aprendizaje Profundo
5.
Oncologist ; 2024 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-39115892

RESUMEN

BACKGROUND: Several guidelines recommend the use of different classifiers to determine the risk of recurrence (ROR) and treatment decisions in patients with HR+HER2- breast cancer. However, data are still lacking for their usefulness in Latin American (LA) patients. Our aim was to evaluate the comparative prognostic and predictive performance of different ROR classifiers in a real-world LA cohort. METHODS: The Molecular Profile of Breast Cancer Study (MPBCS) is an LA case-cohort study with 5-year follow-up. Stages I and II, clinically node-negative HR+HER2- patients (n = 340) who received adjuvant hormone therapy and/or chemotherapy, were analyzed. Time-dependent receiver-operator characteristic-area under the curve, univariate and multivariate Cox proportional hazards regression (CPHR) models were used to compare the prognostic performance of several risk biomarkers. Multivariate CPHR with interaction models tested the predictive ability of selected risk classifiers. RESULTS: Within this cohort, transcriptomic-based classifiers such as the recurrence score (RS), EndoPredict (EP risk and EPClin), and PAM50-risk of recurrence scores (ROR-S and ROR-PC) presented better prognostic performances for node-negative patients (univariate C-index 0.61-0.68, adjusted C-index 0.77-0.80, adjusted hazard ratios [HR] between high and low risk: 4.06-9.97) than the traditional classifiers Ki67 and Nottingham Prognostic Index (univariate C-index 0.53-0.59, adjusted C-index 0.72-0.75, and adjusted HR 1.85-2.54). RS (and to some extent, EndoPredict) also showed predictive capacity for chemotherapy benefit in node-negative patients (interaction P = .0200 and .0510, respectively). CONCLUSION: In summary, we could prove the clinical validity of most transcriptomic-based risk classifiers and their superiority over clinical and immunohistochemical-based methods in the heterogenous, real-world node-negative HR+HER2- MPBCS cohort.

6.
Artículo en Inglés | MEDLINE | ID: mdl-39031874

RESUMEN

PURPOSE: According to previous biomechanical studies, the success of meniscus root repair depends on the suture-meniscus interface and optimisation of this procedure seems to be critical. A progressive, reliable and adjustable knot has numerous advantages in meniscal repair since the surgeon can adapt and meticulously tune the final strength of the fixation. We hypothesised that a single passage of one tape at two different points of the posterior meniscal root with a modified Nice knot configuration may allow similar or superior fixation for root repair compared to the cinch stitch suture technique. METHODS: Posterior root repair of medial and lateral meniscus was performed on 26 porcine knees. In group (A), two simple cinch stitches were applied, and in group (B), a modified Nice knot was used in a crossmatch configuration. For both groups, two passages through the meniscus with a 2-mm braided tape were used, and a single transosseous tibial tunnel technique was performed and tested in pull-out conditions. RESULTS: The modified Nice knot showed an improved biomechanical performance considering the maximum failure load for both the medial (600.7 ± 77.5 N) and lateral (686.1 ± 83.5 N) (p = 0.006) posterior root fixation when compared to a double cinch stitch (558.0 ± 123.9 N) and (629.0 ± 110.2 N) (p = 0.178) for medial and lateral fixation, respectively. The maximum stiffness was also higher for the modified Nice knot configuration for both medial (17.1 ± 1.5 vs. 13.3 ± 1.6 N/mm) and lateral meniscus (20.0 ± 2.6 vs. 13.8 ± 2.3 N/mm), being this difference statistically significative (p = 0.001). CONCLUSIONS: The modified Nice knot allowed better adaptation in the pull-out tests and presented higher fixation strength, stiffness and reproducibility, with lower standard deviation, being at the same time economically advantageous, since only one tape is needed. LEVEL OF EVIDENCE: Level III.

7.
Sci Total Environ ; 948: 174902, 2024 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-39053551

RESUMEN

Understanding local hydraulic conditions is imperative to coastal harmful algal bloom (HAB) monitoring. The research summarized herein describes how the locations and tidal phases selected for coastal hazard sampling can influence measurement results used to guide management decisions for HABs. Our study was conducted in Frenchman Bay, Maine, known for its complex deglaciated coastline, strong tidal influence, and shellfishing activities that are susceptible to problematic HABs such as those produced by some species (spp.) of the diatom genus Pseudo-nitzschia. In-situ measurements of current velocity, density, and turbulence collected over a semidiurnal tidal cycle and a companion numerical model simulation of the study area provide concurrent evidence of two adjacent counter-rotating sub-mesoscale eddies (2-4 km diameter) that persist in the depth-averaged residual circulation. The eddies are generated in the wake of several islands in an area with abrupt bathymetric gradients, both legacy conditions partly derived from deglaciation ∼15 kya. Increased concentrations of Pseudo-nitzschia spp. measured during the semidiurnal survey follow a trend of elevated turbulent dissipation rates near the water surface, indicating that surface sampling alone might not adequately indicate species abundance. Additional measurements of Pseudo-nitzschia spp. from two years of weekly sampling in the region show that algal cell abundance is highest where residual eddies form. These findings provide incentive to examine current practices of HAB monitoring and management by linking coastal geomorphology to hydraulic conditions influencing HAB sampling outcomes, coastal morphometric features to material accumulation hotspots, and millennial time scales to modern hydraulic conditions.


Asunto(s)
Diatomeas , Monitoreo del Ambiente , Estuarios , Floraciones de Algas Nocivas , Hidrodinámica , Diatomeas/fisiología , Monitoreo del Ambiente/métodos , Maine , Movimientos del Agua
8.
Rev Bras Enferm ; 77(3): e20230428, 2024.
Artículo en Inglés, Portugués | MEDLINE | ID: mdl-38896660

RESUMEN

OBJECTIVES: to analyze the risk areas for tuberculosis and the influences of social protection on the development of treatment for the disease in the municipality of São Luís, Maranhão. METHODS: this is explanatory sequential mixed method research. In the quantitative phase, the data were obtained from the Notifiable Diseases Information System from 2010 to 2019, with georeferencing being carried out to identify areas vulnerable to tuberculosis. In the qualitative phase, semi-structured interviews were carried out with individuals who received social benefits. RESULTS: 7,381 cases were geocoded, and, from the purely spatial scanning analysis, it was possible to identify 13 spatial clusters of risk. As for the interviews, there was a positive relationship between patient improvement and receiving benefits. CONCLUSIONS: geographic space and social determinants are relevant for reorienting monitoring actions for the conditions that generate the health-disease process.


Asunto(s)
Investigación Cualitativa , Tuberculosis , Humanos , Brasil/epidemiología , Femenino , Masculino , Poblaciones Vulnerables/estadística & datos numéricos , Poblaciones Vulnerables/psicología , Adulto , Persona de Mediana Edad
9.
Infection ; 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38856806

RESUMEN

PURPOSE: Most data regarding infective endocarditis (IE) after transcatheter aortic valve implantation (TAVI) comes from TAVI registries, rather than IE dedicated cohorts. The objective of our study was to compare the clinical and microbiological profile, imaging features and outcomes of patients with IE after SAVR with a biological prosthetic valve (IE-SAVR) and IE after TAVI (IE-TAVI) from 6 centres with an Endocarditis Team (ET) and broad experience in IE. METHODS: Retrospective analysis of prospectively collected data. From the time of first TAVI implantation in each centre to March 2021, all consecutive patients admitted for IE-SAVR or IE-TAVI were prospectively enrolled. Follow-up was monitored during admission and at 12 months after discharge. RESULTS: 169 patients with IE-SAVR and 41 with IE-TAVI were analysed. Early episodes were more frequent among IE-TAVI. Clinical course during hospitalization was similar in both groups, except for a higher incidence of atrioventricular block in IE-SAVR. The most frequently causative microorganisms were S. epidermidis, Enterococcus spp. and S. aureus in both groups. Periannular complications were more frequent in IE-SAVR. Cardiac surgery was performed in 53.6% of IE-SAVR and 7.3% of IE-TAVI (p=0.001), despite up to 54.8% of IE-TAVI patients had an indication. No differences were observed about death during hospitalization (32.7% vs 35.0%), and at 1-year follow-up (41.8% vs 37.5%), regardless of whether the patient underwent surgery or not. CONCLUSION: Patients with IE-TAVI had a higher incidence of early prosthetic valve IE. Compared to IE-SAVR, IE-TAVI patients underwent cardiac surgery much less frequently, despite having surgical indications. However, in-hospital and 1-year mortality rate was similar between both groups.

10.
PLoS One ; 19(6): e0305063, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38848395

RESUMEN

Tuberculosis (TB) in people living with HIV (PLHIV) is usually paucibacillary and the smear microscopy has limitations and may lead to high proportions of non-confirmed pulmonary tuberculosis (NC-PTB). Despite culture being the reference method, it usually takes 6 to 8 weeks to produce the results. This study aimed to analyze the effect of a rapid molecular test (Xpert) in the confirmatory rate of PTB among PLHIV, from 2010 to 2020, in São Paulo state, Brazil. This is an ecological study with time series analysis of the trend and the NC-PTB rates before and after Xpert implementation in 21 municipalities. The use of Xpert started and gradually increased after 2014, while the rate of NC-PTB in PLHIV decreased over this time, being more significant between late 2015 and mid-2017. The city of Ribeirão Preto stands out for having the highest percentage (75.0%) of Xpert testing among PLHIV and for showing two reductions in the NC-PTB rate. The cities with low Xpert coverage had a slower and smaller decrease in the NC-PTB rate. Despite being available since 2014, a significant proportion of PLHIV suspected of PTB in the state of São Paulo did not have an Xpert ordered by the doctors. The implementation of Xpert reduced the NC-PTB rates with growing effect as the coverage increased in the municipality.


Asunto(s)
Infecciones por VIH , Mycobacterium tuberculosis , Tuberculosis Pulmonar , Humanos , Brasil/epidemiología , Tuberculosis Pulmonar/diagnóstico , Tuberculosis Pulmonar/epidemiología , Tuberculosis Pulmonar/microbiología , Infecciones por VIH/complicaciones , Infecciones por VIH/epidemiología , Mycobacterium tuberculosis/aislamiento & purificación , Mycobacterium tuberculosis/genética , Técnicas de Diagnóstico Molecular/métodos , Esputo/microbiología
11.
Sci Rep ; 14(1): 13196, 2024 06 08.
Artículo en Inglés | MEDLINE | ID: mdl-38851847

RESUMEN

Interleukin-10 (IL-10) is an immunomodulatory cytokine that plays a pivotal role in the pathogenesis of acute coronary syndromes (ACS). Here, we evaluated the role of IL10 promoter variants as markers for ACS susceptibility in Western Mexican patients as well as its association with IL10 mRNA and IL-10 plasma levels. Three promoter variants (- 1082 A > G, - 819 T > C and - 592 A > C) were analyzed in 300 ACS patients and 300 control group (CG) individuals. IL10 relative gene expression was evaluated in peripheral blood mononuclear cells (PBMC) and IL-10 levels were quantified in plasma. The allelic, genotypic and haplotypic frequencies did not show significant differences between groups. ACS patients had sevenfold higher mRNA IL10 level compared to CG (p = 0.0013). Homozygous C/C carriers in both - 819 T > C and - 592 A > C variants had 0.4-fold higher IL10 mRNA expression than heterozygous and polymorphic allele homozygous genotypes (p = 0.0357) in ACS group. There were significant differences in plasma IL-10 levels in CG and ACS group (1.001 vs 1.777 pg/mL, p = 0.0051). The variants were not markers of susceptibility to ACS in Western Mexican individuals. ACS patients showed higher IL10 expression than CG individuals which could be mediated by - 819 T > C and - 592 A > C variants and pharmacotherapy.


Asunto(s)
Síndrome Coronario Agudo , Predisposición Genética a la Enfermedad , Interleucina-10 , Polimorfismo de Nucleótido Simple , Regiones Promotoras Genéticas , Humanos , Interleucina-10/genética , Interleucina-10/sangre , Síndrome Coronario Agudo/genética , Síndrome Coronario Agudo/sangre , Masculino , Femenino , Persona de Mediana Edad , Anciano , Estudios de Casos y Controles , Genotipo , Alelos , Biomarcadores/sangre , México , Leucocitos Mononucleares/metabolismo , Frecuencia de los Genes , ARN Mensajero/genética , ARN Mensajero/metabolismo
12.
Phys Rev E ; 109(4-2): 045109, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38755876

RESUMEN

Electric fields are commonly used to control the orientation and motion of microscopic metal particles in aqueous suspensions. For example, metallodielectric Janus spheres are propelled by the induced-charge electro-osmotic flow occurring on their metallic side, the most common case in electrokinetics of exploiting symmetry breaking of surface properties for achieving net particle motion. In this work, we demonstrate that a homogeneous metal rod can translate parallel to a dielectric wall as a result of the hydrodynamic wall-particle interaction arising from the induced-charge electro-osmosis on the rod surface. The applied electric field could be either dc or low-frequency ac. The only requirement for a nonvanishing particle velocity is that the axis of the rod be inclined with respect to the wall, i.e., it cannot be neither parallel nor perpendicular. We show numerical results of the rod velocity as a function of rod orientation and distance to the wall. The maximum particle velocity is found for an orientation of between ∼30^{∘} and ∼50^{∘}, depending on the position and aspect ratio of the cylinder. Particle velocities of up to tens of µm/s are predicted for typical conditions in electrokinetic experiments.

13.
Lab Chip ; 24(11): 2968-2974, 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38726642

RESUMEN

Concentration-polarization electroosmosis (CPEO) refers to steady-state electroosmotic flows around charged dielectric micro-particles induced by low-frequency AC electric fields. Recently, these flows were shown to cause repulsion of colloidal particles from the wall of a microfluidic channel when an electric field is applied along the length of the channel. In this work, we exploit this mechanism to demonstrate fractionation of micron-sized polystyrene particles and bacteria in a flow-focusing device. The results are in agreement with predictions of the CPEO theory. The ease of implementation of CPEO-based fractionation in microfluidics makes it an ideal candidate for combining with current techniques commonly used to generate particle lift, such as inertial or viscoelastic focusing, requiring no extra fabrication steps other than inserting two electrodes.

14.
Front Psychol ; 15: 1320169, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38721318

RESUMEN

The literature has well documented the relationship between Adverse Childhood Experiences, personality traits, and well-being. However, less is known about how Benevolent Childhood Experiences (BCEs) relate to "light" personality traits and Flourishing. The study analyzed the effects of BCEs on Flourishing, considering the mediator role of Light Triad traits (Kantianism, Humanism, and Faith in Humanity). The study used a quantitative methodology with a non-experimental, cross-sectional design; 410 Honduran adults responded to the survey, including questions regarding Light Triad personality traits, Flourishing, and BCEs. On average, respondents reported 7.34 BCEs. The number of reported BCEs did not vary significantly between men and women. However, specific BCEs were categorically associated with subjects' sex. A higher proportion of men reported having at least one teacher who cared about the respondent, having opportunities to have a good time, and liking/feeling comfortable with oneself. Flourishing was significantly higher for participants who reported the presence of BCEs. The largest effect size was achieved for the difference in Flourishing scores between those who reported liking school as a child and those who disliked it. The number of Benevolent Childhood Experiences had a significant total and direct effect on Flourishing scores. Significant indirect effects were also identified. Faith in Humanity and Humanism, not Kantianism, mediated the relationship between BCEs and Flourishing. BCEs significantly explained all Light Triad traits. In conclusion, BCEs have significant direct and indirect effects on adult Flourishing; Faith in Humanity and Humanism mediate this relationship.

15.
Rev Bras Epidemiol ; 27: e240015, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38655944

RESUMEN

OBJECTIVE: The aim of this study was to analyze the spatiotemporal evolution of the incidence rates of human immunodeficiency virus (HIV) and acquired immune deficiency syndrome (AIDS) in the state of Paraná, Brazil. METHODS: An ecological study with an analytical component of time series analysis was conducted in the state of Paraná from 2007 to 2022. The data source was the Notifiable Diseases Information System. To study the trend, the Prais-Winsten generalized linear regression model was used by decomposing the time series, and for spatial analysis, the Moran's index was applied. RESULTS: The total sample consisted of 50,676 HIV/AIDS records. The incidence rate showed an increasing trend, with an average growth of 2.14% [95% confidence interval - 95%CI 1.16-3.13] per month. From 2007 to 2014 and from 2015 to 2022, the average number of cases in the state was 105.64 and 159.20 per 100,000 inhabitants, respectively, with significant variation among municipalities. Spatial clusters of high risk persisted in the metropolitan region, the capital, and coastal areas, and a new cluster was observed in the northern region of the state. CONCLUSION: The incidence rates of HIV/AIDS showed an upward trend over time. The number of cases varied considerably in some municipalities, especially in the coastal region. Spatial analysis revealed geospatial patterns of high risk in the main metropolitan areas of Paraná: Curitiba (including the coastal area), Londrina, and Maringá, which share characteristics such as a high degree of urbanization and ongoing economic development.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida , Infecciones por VIH , Análisis Espacio-Temporal , Brasil/epidemiología , Humanos , Síndrome de Inmunodeficiencia Adquirida/epidemiología , Incidencia , Infecciones por VIH/epidemiología , Factores de Tiempo , Masculino , Femenino , Adulto
16.
Sensors (Basel) ; 24(8)2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38676148

RESUMEN

The prevalence of Low Probability of Interception (LPI) and Low Probability of Exploitation (LPE) radars in contemporary Electronic Warfare (EW) presents an ongoing challenge to defense mechanisms, compelling constant advances in protective strategies. Noise radars are examples of LPI and LPE systems that gained substantial prominence in the past decade despite exhibiting a common drawback of limited Doppler tolerance. The Advanced Pulse Compression Noise (APCN) waveform is a stochastic radar signal proposed to amalgamate the LPI and LPE attributes of a random waveform with the Doppler tolerance feature inherent to a linear frequency modulation. In the present work, we derive closed-form expressions describing the APCN signal's ambiguity function and spectral containment that allow for a proper analysis of its detection performance and ability to remove range ambiguities as a function of its stochastic parameters. This paper also presents a more detailed address of the LPI/LPE characteristic of APCN signals claimed in previous works. We show that sophisticated Electronic Intelligence (ELINT) systems that employ Time Frequency Analysis (TFA) and image processing methods may intercept APCN and estimate important parameters of APCN waveforms, such as bandwidth, operating frequency, time duration, and pulse repetition interval. We also present a method designed to intercept and exploit the unique characteristics of the APCN waveform. Its performance is evaluated based on the probability of such an ELINT system detecting an APCN radar signal as a function of the Signal-to-Noise Ratio (SNR) in the ELINT system. We evaluated the accuracy and precision of the random variables characterizing the proposed estimators as a function of the SNR. Results indicate a probability of detection close to 1 and show good performance, even for scenarios with a SNR slightly less than -10 dB. The contributions in this work offer enhancements to noise radar capabilities while facilitating improvements in ESM systems.

17.
J Chem Inf Model ; 64(9): 3865-3873, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38598310

RESUMEN

Previous experimental studies have shown that the isomerization reaction of previtamin D3 (PreD3) to vitamin D3 (VitD3) is accelerated 40-fold when it takes place within a ß-cyclodextrin dimer, in comparison to the reaction occurring in conventional isotropic solutions. In this study, we employ quantum mechanics-based molecular dynamics (MD) simulations and statistical multistructural variational transition state theory to unveil the origin of this acceleration. We find that the conformational landscape in the PreD3 isomerization is highly dependent on whether the system is encapsulated. In isotropic media, the triene moiety of the PreD3 exhibits a rich torsional flexibility. However, when encapsulated, such a flexibility is limited to a more confined conformational space. In both scenarios, our calculated rate constants are in close agreement with experimental results and allow us to identify the PreD3 flexibility restriction as the primary catalytic factor. These findings enhance our understanding of VitD3 isomerization and underscore the significance of MD and environmental factors in biochemical modeling.


Asunto(s)
Simulación de Dinámica Molecular , beta-Ciclodextrinas , beta-Ciclodextrinas/química , Catálisis , Isomerismo , Vitamina D/química , Vitamina D/metabolismo , Teoría Cuántica , Conformación Molecular , Colecalciferol/química , Colecalciferol/metabolismo
19.
Infect Dis Poverty ; 13(1): 17, 2024 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-38369536

RESUMEN

BACKGROUND: Tuberculosis is one of the most significant infectious diseases for global public health. The reallocation of healthcare resources and the restrictions imposed by the COVID-19 pandemic have hindered access to TB diagnosis and treatment. Increases in unfavorable outcomes of the disease have been observed in Brazil. The objective of this study was to analyze the spatial distribution of unfavorable TB treatment outcomes in Brazil before and during the pandemic. METHODS: An ecological study with spatial analysis was conducted with all 5569 municipalities in Brazil. All reported cases of tuberculosis between January 2010 and December 2021, as well as reported cases of COVID-19 from February 2020 to December 2021, were included. The outcomes studied encompass loss to follow-up, drug-resistant tuberculosis, and death. The Getis Ord GI* technique was employed to assess spatial association, and the Kernel density estimator was used to identify areas with concentrated increases or decreases in outcomes. Bivariate Local Moran's I was used to examine the spatial association between outcomes and COVID-19 incidence. The study was approved by the Research Ethics Committee of Ribeirão Preto Nursing School, University of São Paulo. RESULTS: There were 134,394 cases of loss to follow-up, 10,270 cases of drug resistance, and 37,863 deaths. Clusters of high and low values were identified for all three outcomes, indicating significant changes in the spatial distribution patterns. Increases in concentrations were observed for lost to follow-up cases in the Southeast, while reductions occurred in the Northeast, South, and Midwest. Drug-resistant tuberculosis experienced an increase in the Southern and Southeastern regions and a decrease in the Northeast and South. TB-related deaths showed notable concentrations in the Midwest, Northeast, South, and Southeast. There was an increase in high occurrence clusters for deaths after 2020 and 2021 in the Northeast. CONCLUSIONS: The pandemic has brought additional challenges, emphasizing the importance of enhancing efforts and disease control strategies, prioritizing early identification, treatment adherence, and follow-up. This commitment is vital for achieving the goal of tuberculosis elimination.


Asunto(s)
COVID-19 , Tuberculosis Resistente a Múltiples Medicamentos , Tuberculosis , Humanos , Pandemias , Brasil/epidemiología , Objetivos , Desarrollo Sostenible , COVID-19/epidemiología , Tuberculosis/tratamiento farmacológico , Tuberculosis/epidemiología , Resultado del Tratamiento , Tuberculosis Resistente a Múltiples Medicamentos/epidemiología
20.
J Sci Food Agric ; 104(9): 5495-5503, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38363077

RESUMEN

BACKGROUND: Maize is frequently contaminated with deoxynivalenol (DON) and fumonisins B1 (FB1) and B2 (FB2). In the European Union, these mycotoxins are regulated in maize and maize-derived products. To comply with these regulations, industries require a fast, economic, safe, non-destructive and environmentally friendly analysis method. RESULTS: In the present study, near-infrared hyperspectral imaging (NIR-HSI) was used to develop regression and classification models for DON, FB1 and FB2 in maize kernels. The best regression models presented the following root mean square error of cross validation and ratio of performance to deviation values: 0.848 mg kg-1 and 2.344 (DON), 3.714 mg kg-1 and 2.018 (FB1) and 2.104 mg kg-1 and 2.301 (FB2). Regarding classification, European Union legal limits for DON and FB1 + FB2 were selected as thresholds to classify maize kernels as acceptable or not. The sensitivity and specificity were 0.778 and 1 for the best DON classification model and 0.607 and 0.938 for the best FB1 + FB2 classification model. CONCLUSION: NIR-HSI can help reduce DON and fumonisins contamination in the maize food and feed chain. © 2024 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.


Asunto(s)
Contaminación de Alimentos , Fumonisinas , Semillas , Espectroscopía Infrarroja Corta , Tricotecenos , Zea mays , Zea mays/química , Zea mays/microbiología , Fumonisinas/análisis , Contaminación de Alimentos/análisis , Contaminación de Alimentos/prevención & control , Tricotecenos/análisis , Espectroscopía Infrarroja Corta/métodos , Semillas/química , Semillas/microbiología , Imágenes Hiperespectrales/métodos , Micotoxinas/análisis , Micotoxinas/química
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