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1.
Anesthesiology ; 140(4): 752-764, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38207290

RESUMEN

BACKGROUND: Lower fractional inspired oxygen tension (Fio2) during general anesthesia can reduce lung atelectasis. The objectives are to evaluate the effect of two Fio2 (0.4 and 1) during low positive end-expiratory pressure (PEEP) ventilation over lung perfusion distribution, volume, and regional ventilation. These variables were evaluated at two PEEP levels and unilateral lung atelectasis. METHODS: In this exploratory study, 10 healthy female piglets (32.3 ± 3.4 kg) underwent mechanical ventilation in two atelectasis models: (1) bilateral gravitational atelectasis (n = 6), induced by changes in PEEP and Fio2 in three combinations: high PEEP with low Fio2 (Fio2 = 0.4), zero PEEP (PEEP0) with low Fio2 (Fio2 = 0.4), and PEEP0 with high Fio2 (Fio2 = 1); and (2) unilateral atelectasis (n = 6), induced by left bronchial occlusion, with the left lung aerated (Fio2 = 0.21) and low aerated (Fio2 = 1; n = 5 for this step). Measurements were conducted after 10 min in each step, encompassing assessment of respiratory mechanics, oxygenation, and hemodynamics; lung ventilation and perfusion by electrical impedance tomography; and lung aeration and perfusion by computed tomography. RESULTS: During bilateral gravitational atelectasis, PEEP reduction increased atelectasis in dorsal regions, decreased respiratory compliance, and distributed lung ventilation to ventral regions with a parallel shift of perfusion to the same areas. With PEEP0, there were no differences between low and high Fio2 in respiratory compliance (23.9 ± 6.5 ml/cm H2O vs. 21.9 ± 5.0; P = 0.441), regional ventilation, and regional perfusion, despite higher lung collapse (18.6 ± 7.6% vs. 32.7 ± 14.5%; P = 0.045) with high Fio2. During unilateral lung atelectasis, the deaerated lung had a lower shunt (19.3 ± 3.6% vs. 25.3 ± 5.5%; P = 0.045) and lower computed tomography perfusion to the left lung (8.8 ± 1.8% vs. 23.8 ± 7.1%; P = 0.007). CONCLUSIONS: PEEP0 with low Fio2, compared with high Fio2, did not produce significant changes in respiratory system compliance, regional lung ventilation, and perfusion despite significantly lower lung collapse. After left bronchial occlusion, the shrinkage of the parenchyma with Fio2 = 1 enhanced hypoxic pulmonary vasoconstriction, reducing intrapulmonary shunt and perfusion of the nonventilated areas.


Asunto(s)
Atelectasia Pulmonar , Respiración Artificial , Animales , Femenino , Porcinos , Respiración Artificial/métodos , Pulmón/diagnóstico por imagen , Mediciones del Volumen Pulmonar , Atelectasia Pulmonar/diagnóstico por imagen , Atelectasia Pulmonar/terapia , Perfusión , Oxígeno
2.
Environ Res ; 228: 115858, 2023 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-37062481

RESUMEN

Following the Fundão dam failure in Brazil, 60 million m3 of iron-rich tailings were released impacting an extensive area. After this catastrophe, a detailed characterization and monitoring of iron-rich tailings is required for agronomic and environmental purposes. This can be facilitated by using proximal sensors which have been an efficient, fast, and cost-effective tool for eco-friendly analysis of soils and sediments. This work hypothesized that portable X-ray fluorescence (pXRF) spectrometry combined with a pocket-sized (Nix™ Pro) color sensor and benchtop magnetic susceptibilimeter can produce substantial data for fast and clean characterization of iron-rich tailings. The objectives were to differentiate impacted and non-impacted areas (soils and sediments) based on proximal sensors data, and to predict attributes of agronomic and environmental importance. A total of 148 composite samples were collected on totally impacted, partially impacted, and non-impacted areas (natural soils). The samples were analyzed via pXRF to obtain the total elemental composition; via Nix™ Pro color sensor to obtain the red (R), green (G), and blue (B) parameters; and assessed for magnetic susceptibility (MS). The same samples used for analyses via the aforementioned sensors were wet-digested (USEPA 3051a method) followed by ICP-OES quantification of potentially toxic elements. Principal component analysis was performed to differentiate impacted and non-impacted areas. The pXRF data alone or combined with other sensors were used to predict soil agronomic properties and semi-total concentration of potentially toxic elements via random forest regression. For that, samples were randomly separated into modeling (70%) and validation (30%) datasets. The pXRF proved to be an efficient method for rapid and eco-friendly characterization of iron-rich tailings, allowing a clear differentiation of impacted and non-impacted areas. Also, important soil agronomic properties (clay, cation exchange capacity, soil organic carbon, pH and macronutrients availability) and semi-total concentrations of Ba, Pb, Cr, V, Cu, Co, Ni, Mn, Ti, and Li were accurately predicted (based upon the lowest RMSE and highest R2 and RPD values). Sensor data fusion (pXRF + Nix Pro + MS) slightly improved the accuracy of predictions. This work highlights iron-rich tailings from the Fundão dam failure can be in detail characterized via pXRF ex situ, providing a secure basis for complementary studies in situ aiming at identify contaminated hot spots, digital mapping of soil and properties variability, and embasing pedological, agricultural and environmental purposes.


Asunto(s)
Hierro , Contaminantes del Suelo , Hierro/análisis , Suelo/química , Brasil , Carbono/análisis , Monitoreo del Ambiente/métodos , Contaminantes del Suelo/análisis
3.
Sensors (Basel) ; 23(3)2023 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-36772299

RESUMEN

Intelligent Transportation Systems (ITSs) are systems that aim to provide innovative services for road users in order to improve traffic efficiency, mobility and safety. This aspect of safety is of utmost importance for Vulnerable Road Users (VRUs), as these users are typically more exposed to dangerous situations, and their vehicles also possess poorer safety mechanisms when in comparison to regular vehicles on the road. Implementing automatic safety solutions for VRU vehicles is challenging since they have high agility and it can be difficult to anticipate their behavior. However, if equipped with communication capabilities, the generated Vehicle-to-Anything (V2X) data can be leveraged by Machine Learning (ML) mechanisms in order to implement such automatic systems. This work proposes a VRU (motorcyclist) collision prediction system, utilizing stacked unidirectional Long Short-Term Memorys (LSTMs) on top of communication data that is generated using the VEINS simulation framework (coupling the Simulation of Urban MObility (SUMO) and Network Simulator 3 (ns-3) tools). The proposed system performed well in two different scenarios: in Scenario A, it predicted 96% of the collisions, averaging 4.53 s for Average Prediction Time (s) (APT) and with a Correct Decision Percentage (CDP) of 41% and 78 False Positives (FPs); in Scenario B, it predicted 95% of the collisions, with a 4.44 s APT, while the CDP was 43% with 68 FPs. The results show the effectiveness of the approach: using ML methods on V2X data allowed the prediction of most of the simulated accidents. Nonetheless, the presence of a relatively high number of FPs does not allow for the usage of automatic safety features (e.g., emergency breaking in the passenger vehicles); thus, collision avoidance must be achieved manually by the drivers.

4.
J Strength Cond Res ; 37(2): 351-357, 2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36354748

RESUMEN

ABSTRACT: Ferreira, ABdM, Ribeiro, BLL, Batista, EdS, Dantas, MP, and Mortatti, AL. The influence of different training load magnitudes on sleep pattern, perceived recovery, and stress tolerance in young soccer players. J Strength Cond Res 37(2): 351-357, 2023-The aim of this study was to analyze the influence of 3 weeks on sleep parameters, perceived recovery, and stress tolerance in young soccer players using different training load magnitudes. A total of 13 young male soccer athletes (15.9 ± 0.5 years; 68.7 ± 6.1 kg; 170 ± 7 cm) who performed 3 typical training weeks with different workloads were analyzed. The external training load (ETL) was verified by the PlayerLoad method, and the internal training load (ITL) was determined using the session rating of perceived exertion method. Sleep was monitored using a wrist-actigraphy monitor. Sleep variables, including total time in bed (TTB), total sleep time (TST), sleep latency (SL), wake after sleep onset (WASO), and sleep efficiency (SE), were evaluated across all nights of sleep. The recovery status was assessed with the perceived recovery status (PRS) scale, and the stress tolerance was monitored using the "daily analysis of life demands of athletes" questionnaire. There was an increase in sleep time during the week with the highest training load (week 2) (TTB: +35 minutes, TST: +46 minutes, SL: -5 minutes, SE: +3%). There was no difference in the PRS or in the stress tolerance during the evaluation weeks. A very large within-individual correlation was observed between ITL and ETL ( r = 0.78) and moderate within-individual correlation between ETL and TST ( r = 0.34), between ITL and TST ( r = 0.45), and between ITL and SE ( r = 0.359). These results showed that there was an increase in TST during a microcycle with intensified loads, without impairing bedtime and resulting in maintenance of the perceived recovery or stress tolerance values.


Asunto(s)
Acondicionamiento Físico Humano , Fútbol , Humanos , Masculino , Sueño , Encuestas y Cuestionarios , Latencia del Sueño , Duración del Sueño , Esfuerzo Físico , Acondicionamiento Físico Humano/métodos
5.
Environ Res ; 215(Pt 1): 114147, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36063907

RESUMEN

Mercury (Hg) toxicity in soils depends on Hg species and other physical and chemical attributes, as selenium (Se) hotspots in soils, particularly relevant in Amazonian soils. The study of Hg species and their relations in representative locations of the Amazon rainforest biome is critical for assessing the potential risks of Hg in this environment. This work aimed to determine the concentration of total Hg and its species (Hg0, Hg22+ and Hg2+), and to correlate Hgtotal concentration with total elemental composition, magnetic susceptibility, and physicochemical attributes of Amazon soils. Nine sites in the Amazon rainforest biome, Brazil, were selected and analyzed for their chemical, physical, and mineralogical attributes. The clay fraction of the studied Amazon soils is dominated by kaolinite, goethite, hematite, gibbsite, and quartz. Mica was also found in soils from the States of Acre and Amazonas. Hgtotal ranged from 21.5 to 208 µg kg-1 (median = 104 µg kg-1), and the concentrations did not exceed the threshold value established for Brazilian soils (500 µg kg-1). The Hg2+ was notably the predominant species. Its occurrence and concentration were correlated with the landscape position and soil attributes. Hgtotal was moderately and positively correlated with TiO2, clay, and Se. The findings showed that geographic location, geological formation, and pedological differences influence the heterogeneity and distribution of Hgtotal in the studied soil classes. Thus, a detailed characterization and knowledgment of the soil classes is very important to clarify the complex behavior of this metal in the Amazon rainforest biome.


Asunto(s)
Mercurio , Selenio , Contaminantes del Suelo , Brasil , Arcilla , Ecosistema , Monitoreo del Ambiente , Caolín , Mercurio/análisis , Cuarzo , Bosque Lluvioso , Selenio/análisis , Suelo/química , Contaminantes del Suelo/análisis
6.
Sensors (Basel) ; 22(22)2022 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-36433475

RESUMEN

Prosumers are emerging in the power and energy market to provide load flexibility to smooth the use of distributed generation. The volatile behavior increases the production prediction complexity, and the demand side must take a step forward to participate in demand response events triggered by a community manager. If balance is achieved, the participants should be compensated for the discomfort caused. The authors in this paper propose a methodology to optimally manage a community, with a focus on the remuneration of community members for the provided flexibility. Four approaches were compared and evaluated, considering contextual tariffs. The obtained results show that it was possible to improve the fairness of the remuneration, which is an incentive and compensation for the loss of comfort. The single fair remuneration approach was more beneficial to the community manager, since the total remuneration was lower than the remaining approaches (163.81 m.u. in case study 3). From the prosumers' side, considering a clustering method was more advantageous, since higher remuneration was distributed for the flexibility provided (196.27 m.u. in case study 3).


Asunto(s)
Remuneración , Humanos
7.
Actas Esp Psiquiatr ; 50(1): 63-64, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35103299

RESUMEN

The COVID-19 pandemic has already infected more than 182 million people and killed more than 4 million all over the globe. In addition to its direct health effects, lockdowns and other draconian public health measures, along with an expected economic crisis of unprecedent magnitude, unpre- dictable social effects are being generated.


Asunto(s)
COVID-19 , Control de Enfermedades Transmisibles , Deluciones , Brotes de Enfermedades , Humanos , Pandemias , SARS-CoV-2
8.
Curr Microbiol ; 78(1): 33-54, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33108493

RESUMEN

Endophytes are microorganisms that live inside vegetal tissues without causing any loss to the host plant. They display wide biosynthetic capacity when producing several bioactive secondary metabolites, whose induction could be related to activation of genes, which might be silent or expressed depending on the geographic characteristics from where the endophytic was isolated. The extraordinary richness of the Brazilian biodiversity has encouraged several research groups in the endophytic bioprospecting. This review covers natural products reported by studies on from the Brazilian endophytic fungi cultures and classified them into three chemical classes (terpenes, phenolic, and nitrogen-containing compounds). For discussion purposes, Principal Component Analysis (PCA) was used as an unsupervised explorative method to evaluate the chemical variation in the Brazilian endophyte dataset. In addition, the dendrogram from the Hierarchical Clustering Analysis (HCA) confirmed the PCA results, and HCA could identify some main endophytic clusters. Our analysis clarified how the secondary metabolites were distributed in the different Brazilian endophyte strains, and this information will be a reliable guide that will support researchers to design microbial culture strategies.


Asunto(s)
Endófitos , Hongos , Bioprospección , Brasil , Endófitos/genética , Hongos/genética , Plantas
9.
Environ Monit Assess ; 193(4): 203, 2021 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-33751261

RESUMEN

On November 5, 2015, the Fundão dam collapsed and released > 60 million m3 of iron-rich mining sediments into the Doce river basin, covering >1000 ha of floodplain soils across ~80 km from the rupture. The characterization of alluvial mud covering and/or mixed with native soil is a priority for successful environmental rehabilitation. Portable X-ray fluorescence (pXRF) spectrometry was used to (1) assess the elemental composition of native soils and alluvial mud across impacted riparian areas; and 2) predict fertility properties of the mud and soils that are crucial for environmental rehabilitation and vegetation establishment (e.g., pH, available macro and micronutrients, cation exchange capacity, organic matter). Native soils and alluvial mud were sampled across impacted areas and analyzed via pXRF and conventional laboratory methods. Random forest (RF) regression was used to predict fertility properties using pXRF data for pooled soil and alluvial mud samples. Mud and native surrounding soils were clearly differentiated based on chemical properties determined via pXRF (mainly SiO2, Al2O3, Fe2O3, TiO2, and MnO). The pXRF data and RF models successfully predicted pH for pooled samples (R2 = 0.80). Moderate predictions were obtained for soil organic matter (R2 = 0.53) and cation exchange capacity (R2 = 0.54). Considering the extent of impacted area and efforts required for successful environmental rehabilitation, the pXRF spectrometer showed great potential for screening impacted areas. It can assess total elemental composition, differentiate alluvial mud from native soils, and reasonably predict related fertility properties in pooled heterogeneous substrates (native soil + mud + river sediments).


Asunto(s)
Desastres , Contaminantes del Suelo , Brasil , Monitoreo del Ambiente , Hierro , Dióxido de Silicio , Suelo , Contaminantes del Suelo/análisis , Espectrometría por Rayos X
10.
Clin Lab ; 66(7)2020 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-32658409

RESUMEN

BACKGROUND: There has increasingly been an interest in histological remission as a therapeutic endpoint in inflammatory bowel disease. The aim of this study was to evaluate the utility of a variety of inflammatory - nutritional markers for predicting histological disease activity in patients diagnosed with Crohn's disease. METHODS: Patients with Crohn's disease that had requisite endoscopic, pathological, and laboratory data were retrospectively enrolled in the study. Relevant clinical, laboratory, endoscopic, and pathological data were abstracted. The neutrophil:lymphocyte ratio (NLR), lymphocyte:monocyte ratio (LMR), platelet:lymphocyte ratio (PLR), red blood cell distribution width (RDW), modified Glasgow Prognostic score (mGPS), Prognostic Nutritional Index (PNI), Geriatric Nutritional Risk index (GNRI), CRP/Albumin ratio (CAR), Iron:Ferritin ratio (Fe:F) and the Systemic immune inflammation index (SII) were calculated. The cohort was stratified by presence of histological disease on colonoscopy, and groups were compared with appropriate statistical methods. RESULTS: When comparing patients without histological disease to those with disease, there was a statistically significant difference in CAR (2.9 ± 1.5 vs. 4.2 ± 2, p = 0.001), RDW (13.4 ± 1.3 vs. 14.5 ± 1.8, p = 0.008), PNI (52.4 ± 6.2 vs. 47.4 ± 9.3, p = 0.03), and mGPS (0.2 ± 0.4 vs. 0.6 ± 0.7, p = 0.01). For predicting histological activity, ROC analyses indicated an optimal cutoff of 0.3 for CAR (AUC 0.8, PPV 90.5%), 13.5 for RDW (AUC 0.7, PPV 84.1), 86.1 for PNI (AUC 0.7, PPV 86.1) and > 0 for mGPS (AUC 0.6, PPV 85.2%). The NLR, LMR, PLR, GNRI, Fe: F, and SII did not meet statistical significance (p = 0.4, 0.08, 0.2, 0.5, 0.6, and 0.3, respectively). CONCLUSIONS: We report on ten biomarkers, many of them never studied in Crohn's disease, which can help in predicting the presence of active histological disease. Larger prospective studies are needed to investigate the utility of these biomarkers alone and in combination.


Asunto(s)
Enfermedad de Crohn , Anciano , Biomarcadores , Enfermedad de Crohn/diagnóstico , Humanos , Linfocitos , Pronóstico , Estudios Prospectivos , Estudios Retrospectivos
11.
Sensors (Basel) ; 20(9)2020 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-32365461

RESUMEN

Foliar analysis is very important for the nutritional management of crops and as a supplemental parameter for soil fertilizer recommendation. The elemental composition of plants is traditionally obtained by laboratory-based methods after acid digestion of ground and sieved leaf samples. This analysis is time-consuming and generates toxic waste. By comparison, portable X-ray fluorescence (pXRF) spectrometry is a promising technology for rapid characterization of plants, eliminating such constraints. This worked aimed to assess the pXRF performance for elemental quantification of leaf samples from important Brazilian crops. For that, 614 samples from 28 plant species were collected across different regions of Brazil. Ground and sieved samples were analyzed after acid digestion (AD), followed by quantification via inductively coupled plasma optical emission spectroscopy (ICP-OES) to determine the concentration of macronutrients (P, K, Ca, Mg, and S) and micronutrients (Fe, Zn, Mn, and Cu). The same plant nutrients were directly analyzed on ground leaf samples via pXRF. Four certified reference materials (CRMs) for plants were used for quality assurance control. Except for Mg, a very strong correlation was observed between pXRF and AD for all plant-nutrients and crops. The relationship between methods was nutrient- and crop-dependent. In particular, eucalyptus displayed optimal correlations for all elements, except for Mg. Opposite to eucalyptus, sugarcane showed the worst correlations for all the evaluated elements, except for S, which had a very strong correlation coefficient. Results demonstrate that for many crops, pXRF can reasonably quantify the concentration of macro- and micronutrients on ground and sieved leaf samples. Undoubtedly, this will contribute to enhance crop management strategies concomitant with increasing food quality and food security.


Asunto(s)
Productos Agrícolas/química , Monitoreo del Ambiente/métodos , Hojas de la Planta/química , Espectrometría por Rayos X , Oligoelementos/análisis , Brasil , Grano Comestible , Fertilizantes , Suelo , Contaminantes del Suelo
12.
Prostate ; 78(4): 289-293, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29315701

RESUMEN

BACKGROUND: McNeal divided the human prostate into three major anatomical areas: the peripheral zone (PZ), the central zone (CZ), and the transition zone (TZ). Each of these areas is biologically and histologically distinct. The PZ and TZ have clinical significance and are associated with prostate cancer (PC) and benign prostatic hyperplasia (BPH), respectively. Therefore, the objective of the present study was to quantitatively and qualitatively analyze the parenchymal and stromal components that constitute the different prostate zones. METHODS: We assessed 19 samples from each prostate zone. The samples were obtained from necropsies of young people between 18 and 32 years of age with intact urogenital tracts. The samples were fixed in 4% buffered formalin and processed for paraffin embedding. Sections with a thickness of five micrometres were obtained from each sample. The sections were stained using histochemical and immunohistochemical techniques to identify the acinar and stromal components of each zone. Photomicrographs were obtained for morphometric analysis using an algorithm based on color segmentation. Data were analyzed using one-way analysis of variance (ANOVA) with the Bonferroni post-test. Differences with P < 0.05 were regarded as statistically significant. RESULTS: Collagen fibres were more numerous in the TZ (+40.26%; P = 0.0230) than in the PZ. Muscle fibres were also more numerous in the TZ (+47.05%; P = 0.0120) than in the PZ. Elastic system fibres in the TZ significantly differed from those in the PZ (+84.61%; P = 0.0012) and the CZ (+61.66%; P = 0.0074). Similarly, nerves in the PZ (-42.86%; P = 0.0107) significantly differed from nerves in the CZ. Epithelial height was lower in the TZ than in the PZ (-30.17%; P = 0.0034) and the CZ (-25.01%; P = 0.0330). CONCLUSION: Our objective, quantitative data regarding the various elements that constitute the normal prostate stroma allowed us to reveal differences among prostate zones. This study established patterns for normal parameters and may be used for posterior comparisons in histopathological analysis.


Asunto(s)
Próstata/anatomía & histología , Adolescente , Adulto , Humanos , Inmunohistoquímica/métodos , Masculino , Adulto Joven
13.
J Anim Ecol ; 86(5): 1214-1223, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28656732

RESUMEN

Niche conservatism, i.e. the retention of a species' fundamental niche through evolutionary time, is cornerstone for biological invasion assessments. The fact that species tend to maintain their original climate niche allows predictive maps of invasion risk to anticipate potential invadable areas. Unravelling the mechanisms driving niche shifts can shed light on the management of invasive species. Here, we assessed niche shifts in one of the world's worst invasive species: the wild boar Sus scrofa. We also predicted potential invadable areas based on an ensemble of three ecological niche modelling methods, and evaluated the performance of models calibrated with native vs. pooled (native plus invaded) species records. By disentangling the drivers of change on the exotic wild boar population's niches, we found strong evidence for niche conservatism during biological invasion. Ecological niche models calibrated with both native and pooled range records predicted convergent areas. Also, observed niche shifts are mostly explained by niche unfilling, i.e. there are unoccupied areas in the exotic range where climate is analogous to the native range. Niche unfilling is expected as result of recent colonization and ongoing dispersal, and was potentially stronger for the Neotropics, where a recent wave of introductions for pig-farming and game-hunting has led to high wild boar population growth rates. The invasive potential of wild boar in the Neotropics is probably higher than in other regions, which has profound management implications if we are to prevent their invasion into species-rich areas, such as Amazonia, coupled with expansion of African swine fever and possibly great economic losses. Although the originally Eurasian-wide distribution suggests a pre-adaptation to a wide array of climates, the wild boar world-wide invasion does not exhibit evidence of niche evolution. The invasive potential of the wild boar therefore probably lies on the reproductive, dietary and morphological characteristics of this species, coupled with behavioural thermoregulation.


Asunto(s)
Distribución Animal , Regulación de la Temperatura Corporal , Clima , Especies Introducidas , Sus scrofa , Animales , Cambio Climático , Dieta , Ecosistema , Reproducción , Porcinos
14.
Parasitol Res ; 115(11): 4327-4334, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27492200

RESUMEN

In an effort to identify novel therapeutic alternatives for the treatment of malaria, the present study evaluated the antimalarial effect of the crude hydroalcoholic extract (HCE) from the leaves of Chenopodium ambrosioides L. For this purpose, the molecular affinity between the total proteins from erythrocytes infected with Plasmodium falciparum and HCE or chloroquine was evaluated by surface plasmon resonance (SPR). Subsequently, the plasmodicidal potential of HCE was assessed in a P. falciparum culture. Using BALB/c mice infected with Plasmodium berghei intraperitoneally (ip.), we evaluated the effects of ip. treatment, for three consecutive days (day 7, 8, and 9 after infection), with chloroquine (45 mg/kg) or HCE (5 mg/kg), considering the survival index and the parasitaemia. The groups were compared to an untreated control group that receives only PBS at the same periods. The results indicated that HCE could bind to the total proteins of infected erythrocytes and could inhibit the parasite growth in vitro (IC50 = 25.4 g/mL). The in vivo therapeutic treatment with HCE increased the survival and decreased the parasitaemia in the infected animals. Therefore, the HCE treatment exhibited a significant antiplasmodial effect and may be considered as a potential candidate for the development of new antimalarial drugs.


Asunto(s)
Antimaláricos/farmacología , Chenopodium ambrosioides/química , Malaria/tratamiento farmacológico , Parasitemia/tratamiento farmacológico , Extractos Vegetales/farmacología , Plasmodium berghei/efectos de los fármacos , Plasmodium falciparum/efectos de los fármacos , Animales , Cloroquina/farmacología , Eritrocitos/parasitología , Humanos , Ratones , Ratones Endogámicos BALB C , Hojas de la Planta/metabolismo , Resonancia por Plasmón de Superficie
15.
Planta ; 241(6): 1325-36, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25677754

RESUMEN

MAIN CONCLUSION: Co-cultures of Pinus pinaster with Bursaphelenchus xylophilus were established as a biotechnological tool to evaluate the effect of nematotoxics addition in a host/parasite culture system. The pinewood nematode (PWN), Bursaphelenchus xylophilus, the causal agent of pine wilt disease (PWD), was detected for the first time in Europe in 1999 spreading throughout the pine forests in Portugal and recently in Spain. Plant in vitro cultures may be a useful experimental system to investigate the plant/nematode relationships in loco, thus avoiding the difficulties of field assays. In this study, Pinus pinaster in vitro cultures were established and compared to in vivo 1 year-old plantlets by analyzing shoot structure and volatiles production. In vitro co-cultures were established with the PWN and the effect of the phytoparasite on in vitro shoot structure, water content and volatiles production was evaluated. In vitro shoots showed similar structure and volatiles production to in vivo maritime pine plantlets. The first macroscopic symptoms of PWD were observed about 4 weeks after in vitro co-culture establishment. Nematode population in the culture medium increased and PWNs were detected in gaps of the callus tissue and in cavities developed from the degradation of cambial cells. In terms of volatiles main components, plantlets, P. pinaster cultures, and P. pinaster with B. xylophilus co-cultures were all ß- and α-pinene rich. Co-cultures may be an easy-to-handle biotechnological approach to study this pathology, envisioning the understanding of and finding ways to restrain this highly devastating nematode.


Asunto(s)
Biotecnología/métodos , Técnicas de Cocultivo/métodos , Pinus/crecimiento & desarrollo , Enfermedades de las Plantas/parasitología , Tylenchida/fisiología , Animales , Pinus/ultraestructura , Brotes de la Planta/crecimiento & desarrollo , Brotes de la Planta/ultraestructura , Compuestos Orgánicos Volátiles/análisis , Agua
16.
FEMS Yeast Res ; 15(5): fov043, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26071437

RESUMEN

Candida parapsilosis is nowadays an emerging opportunistic pathogen and its increasing incidence is part related to the capacity to produce biofilm. In addition, one of the most important C. parapsilosis pathogenic risk factors includes the organisms' selective growth capabilities in hyperalimentation solutions. Thus, in this study, we investigated the role of glucose in C. parapsilosis biofilm modulation, by studying biofilm formation, matrix composition, and structure. Moreover, the expression of biofilm-related genes (BCR1, FKS1 and OLE1) was analysed in the presence of different glucose percentages. The results demonstrated the importance of glucose in the modulation of C. parapsilosis biofilm. The concentration of glucose had direct implications on the C. parapsilosis transition of yeast cells to pseudohyphae. Additionally, it was demonstrated that biofilm-related genes BCR1, FKS1, and OLE1 are involved in biofilm modulation as a result of glucose. The mechanism by which glucose enhances biofilm formation is not fully understood; however, with this study we were able to demonstrate that C. parapsilosis responds to stress conditions caused by elevated levels of glucose by upregulating genes related to biofilm formation (BCR1, FKS1 and OLE1).


Asunto(s)
Biopelículas/crecimiento & desarrollo , Candida/genética , Candida/metabolismo , Glucosa/metabolismo , Proteínas Fúngicas/genética , Perfilación de la Expresión Génica , Glucosiltransferasas/genética , Estearoil-CoA Desaturasa/genética , Factores de Virulencia/genética
17.
Pediatr Radiol ; 45(9): 1427-30, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25686870

RESUMEN

Sporotrichosis in children is rare, and its osteoarticular form is very unusual. Disseminated forms are described mostly in immunocompromised patients. We report a case of a 5-year-old immunocompetent boy with multiple suppurated cutaneous lesions that progressed to polyarthritis of the hands and feet. Radiographic imaging demonstrated multifocal lytic lesions. Sporotrichosis was diagnosed through biopsy and culture. This article describes the radiographic appearance of a rare manifestation of this disease. In areas of high prevalence, the diagnosis of sporotrichosis should be taken into account, even in immunocompetent patients, when dactylitis with lytic lesions is present.


Asunto(s)
Enfermedades Óseas Infecciosas/diagnóstico por imagen , Enfermedades Óseas Infecciosas/microbiología , Sporothrix/aislamiento & purificación , Esporotricosis/diagnóstico por imagen , Esporotricosis/microbiología , Enfermedades Óseas Infecciosas/inmunología , Preescolar , Diagnóstico Diferencial , Humanos , Inmunocompetencia/inmunología , Masculino , Radiografía , Enfermedades Raras/diagnóstico por imagen , Enfermedades Raras/inmunología , Enfermedades Raras/microbiología , Esporotricosis/inmunología
19.
J Cataract Refract Surg ; 50(4): 345-351, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-37962186

RESUMEN

PURPOSE: To study the effect of ocular biomechanics on the prediction error of intraocular lens (IOL) power calculation. SETTING: Centro Hospitalar Universitário do Porto, Porto, Portugal. DESIGN: Prospective longitudinal study. METHODS: This study included 67 subjects. Before cataract surgery subjects underwent biometry with IOLMaster 700 and biomechanical analysis with Corvis Scheimpflug technology. The targeted spherical equivalent was calculated with SRK-T and Barrett Universal II. Associations between prediction error (PE), absolute prediction error (AE), and biometric and biomechanical parameters were performed with stepwise multivariate linear correlation analysis. RESULTS: Using the SRKT formula, there was association between PE and Corvis Biomechanical Index (CBI, B = -0.531, P = .011) and between AE and the horizontal offset between the center of the pupil and the visual axis (angle κ, B = -0.274, P = .007). Considering the Barret Universal II formula, PE was independently associated with anterior chamber depth ( B = -0.279, P = .021) and CBI ( B = -0.520, P = .013) and AE was associated with angle κ ( B = -0.370, P = .007). CONCLUSIONS: A large angle κ may reduce the predictability of IOL power calculation. Ocular biomechanics likely influence the refractive outcomes after IOL implantation. This study showed that eyes with softer corneal biomechanics had more myopic PE. This may relate to anteriorization of the effective lens position. Dynamic measurements may be the way to progress into future formulas.


Asunto(s)
Lentes Intraoculares , Facoemulsificación , Humanos , Implantación de Lentes Intraoculares , Agudeza Visual , Estudios Prospectivos , Fenómenos Biomecánicos , Estudios Longitudinales , Refracción Ocular , Biometría , Estudios Retrospectivos , Óptica y Fotónica
20.
J Refract Surg ; 40(8): e562-e568, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39120018

RESUMEN

PURPOSE: To evaluate the impact of anterior chamber phakic intraocular lens (pIOL) on swept-source optical coherence tomography (SS-OCT) biometric measurements and IOL power calculation. METHODS: This retrospective analysis of 67 eyes of 49 patients with previous anterior chamber pIOL implantation analyzed the accuracy of automatic segmentation of the anterior surface of the crystalline lens and its impact on anterior chamber depth (ACD, measured from epithelium to lens), lens thickness measurements, and IOL power calculation. The sample was divided into two groups: correct detection of the anterior surface of the crystalline lens and inaccurate detection. Segmentation of eyes from the inaccurate detection group was manually corrected and ACD and lens thickness were calculated using ImageJ software. IOL power was calculated using 7 formulas for both measurements. RESULTS: The anterior surface of the crystalline lens was mis-identified in 13 (19.4%) eyes. ACD was underestimated (Δ -0.85 ± 0.33 mm, P < .001) and lens thickness was overestimated (Δ +0.81 ± 0.25 mm, P < .001). Manual correction changed the target spherical equivalent only in the Haigis formula (P = .009). After correction for segmentation bias, the Pearl DGS, Cooke K6, and EVO 2.0 formulas showed the lowest prediction error, with the Pearl DGS showing greatest accuracy within ±1.00 diopters of prediction error range (81.0%). CONCLUSIONS: SS-OCT biometry misidentifies the anterior surface of the crystalline lens in a significant proportion, resulting in significant IOL power calculation error in the Haigis formula. Manual proofing of segmentation is mandatory in every patient with anterior chamber pIOL implantation. After correct segmentation, the Pearl DGS, Cooke K6, and EVO seem to be the best formulas. [J Refract Surg. 2024;40(8):e562-e568.].


Asunto(s)
Cámara Anterior , Biometría , Implantación de Lentes Intraoculares , Lentes Intraoculares Fáquicas , Tomografía de Coherencia Óptica , Humanos , Tomografía de Coherencia Óptica/métodos , Biometría/métodos , Estudios Retrospectivos , Masculino , Adulto , Femenino , Cámara Anterior/diagnóstico por imagen , Refracción Ocular/fisiología , Persona de Mediana Edad , Óptica y Fotónica , Cristalino/diagnóstico por imagen , Miopía/cirugía , Miopía/fisiopatología , Agudeza Visual/fisiología , Adulto Joven
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