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1.
Heliyon ; 10(7): e28482, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38601514

RESUMO

In recent years, the growth of Internet of Things devices has increased the use of sustainable energy sources. An alternative technology is offered by triboelectric nanogenerators (TENGs) that can harvest green energy and convert it into electrical energy. Herein, we assessed three different nopal powder types that were used as triboelectric layers of eco-friendly and sustainable TENGs for renewable energy harvesting from environmental vibrations and powering electronic devices. These nanogenerators were fabricated using waste and recycled materials with a compact design for easy transportation and collocation on non-homogeneous surfaces of different vibration or motion sources. In addition, these TENGs have advantages such as high output performance, stable output voltage, lightweight, low-cost materials, and a simple fabrication process. These nanogenerators use the contact-separation mode between two triboelectric layers to convert the vibration energy into electrical energy. TENG with the best output performance is based on dehydrated nopal powder, generating an output power density of 2.145 mWm-2 with a load resistance of 39.97 MΩ under 3g acceleration and 25 Hz operating frequency. The proposed TENGs have stable output voltages during 22500 operating cycles. These nanogenerators can light 116 ultra-bright blue commercial LEDs and power a digital calculator. Also, the TENGs can be used as a chess clock connected to a mobile phone app for smart motion sensing. These nanogenerators can harvest renewable vibration energy and power electronic devices, sensors, and smart motion sensing.

3.
J Phycol ; 60(2): 483-502, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38264946

RESUMO

Kelp communities are experiencing exacerbated heat-related impacts from more intense, frequent, and deeper marine heatwaves (MHWs), imperiling the long-term survival of kelp forests in the climate change scenario. The occurrence of deep thermal anomalies is of critical importance, as elevated temperatures can impact kelp populations across their entire bathymetric range. This study evaluates the impact of MHWs on mature sporophytes of Pterygophora californica (walking kelp) from the bathymetric extremes (8-10 vs. 25-27 m) of a population situated in Baja California (Mexico). The location is near the southernmost point of the species's broad distribution (from Alaska to Mexico). The study investigated the ecophysiological responses (e.g., photobiology, nitrate uptake, oxidative stress) and growth of adult sporophytes through a two-phase experiment: warming simulating a MHW and a post-MHW phase without warming. Generally, the effects of warming differed depending on the bathymetric origin of the sporophytes. The MHW facilitated essential metabolic functions of deep-water sporophytes, including photosynthesis, and promoted their growth. In contrast, shallow-water sporophytes displayed metabolic stress, reduced growth, and oxidative damage. Upon the cessation of warming, certain responses, such as a decline in nitrate uptake and net productivity, became evident in shallow-water sporophytes, implying a delay in heat-stress response. This indicates that variation in temperatures can result in more prominent effects than warming alone. The greater heat tolerance of sporophytes in deeper waters shows convincing evidence that deep portions of P. californica populations have the potential to serve as refuges from the harmful impacts of MHWs on shallow reefs.


Assuntos
Kelp , Nitratos , México , Temperatura Alta , Água , Ecossistema
4.
Int J Radiat Biol ; 100(3): 445-452, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38166555

RESUMO

PURPOSE: Evaluate the structural damage and the changes in the photosynthesis and transpiration rates of aquatic lirium leaves caused by ultrasound (US) irradiation in search of environmentally friendly methodologies for the control of this weed. MATERIALS AND METHODS: Aquatic lirium plants were extracted from Xochimilco water canals in Mexico City. A part of the group of plants was selected for irradiation, and the rest formed the control group. The irradiation plants group was exposed to US irradiation of 17 kHz frequency and 30 W × 4 output power for 2 h, at noon and 25 °C room temperature. The structural analysis was done with a MOTICAM 1 digital camera, 800 × 600 pixels, incorporated into the MOTIC PSM-1000 optical microscope and edited with Motic Images Plus 2.0 ML software. The total stomata density and the damaged stomata density were determined by dividing the numbers of total and damaged stomata by the visual field area (67,917 mm2), respectively. The leaves' photosynthesis and transpiration rates were measured using an LI-6400XT Portable Photosynthesis System. RESULTS: Significant damage was observed in the stomata and epidermal cells, finding that the average ratio between the damaged and total stomata densities as a function of time (days) showed an exponential increase described by a Box-Lucas equation with a saturation value near unity and a maximum rate of change of the density of damaged stomata on zero-day (immediately after irradiation), decreasing as the days go by. The transpiration rate showed a sudden increase during the first hour after irradiation, reaching a maximum of 36% of its value before irradiation. It then quickly fell during the next 6 days and more slowly until the 21st day, decreasing 79.9% of its value before irradiation. The photosynthetic rate showed similar behavior with a 37.7% maximum increment and a 73.6% minimum decrease of its value before irradiation. CONCLUSIONS: The results of structural stomata damage on the ultrasound-irradiated aquatic lirium leaves are consistent with an excessive ultrasound stimulation on stomata's mechanical operation by guard cells that produce the measured significant increase of the photosynthetic and transpiration rates during the first hour after irradiation. The initial high evaporation could alter the water potential gradient, with a possible generation of tensions in the xylem that could cause embolism in their conduits. The loss of xylem conductivity or hydraulic failure would be consistent with the observed significant fall in the photosynthesis and transpiration rates of the aquatic lirium leaves after its sudden rise in the first hour after irradiation.


Assuntos
Estômatos de Plantas , Transpiração Vegetal , Estômatos de Plantas/fisiologia , Transpiração Vegetal/fisiologia , Fotossíntese , Folhas de Planta , Água
5.
Heliyon ; 9(7): e17819, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37501959

RESUMO

The consumption of antioxidants can prevent chronic non-communicable diseases and the exotic Colombian fruits, goldenberry (Physalis peruviana L.) and purple passion fruit (Passiflora edulis f. Edulis Sims), are rich in bioactive compounds. The aim of this work was to characterize and optimize the antioxidant activity of these fruits blend. The fruits were classified according to their maturity stages, the freeze-dried extracts were physiochemically characterized, and polyphenols, carotenoids and antioxidant activity were quantified, and an experimental mixture design was applied to optimize the antioxidant activity of the bend. For the goldenberry the maturity stage 3 had higher iron-reducing capacity and higher content of polyphenols. Meanwhile, for the purple passion fruit, this maturity stage had higher antioxidant activity by all methodologies and a higher concentration of polyphenols; the ultrasound-assisted extraction showed statistical differences for polyphenols, ABTS and FRAP. Antioxidant activity showed significant differences (p < 0.05) between samples (TBARS (3.98 ± 0.14 and 7.03 ± 0.85 µM-MDA/g), ABTS (36.53 ± 2.66 and 29.4 ± 4.88 µMTrolox/g), DPPH (36.53 ± 2.66 and 23.90 ± 0.96µMTrolox/g), ORAC (23.02 ± 0.36 and 32.44 ± 0.94 µM Trolox/g) and total polyphenols (5, 29 ± 0.34 and 9.12 ± 0.37mgGA/g). Some of the carotenoids identified by HPLC-MS in both fruits were lutein, α and ß-carotene, phytoene and lycopene. The optimum bend was goldenberry 0.83 and purple passion fruit 0.17.

6.
Antioxidants (Basel) ; 12(5)2023 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-37237956

RESUMO

One of the main causes of food spoilage is the lipid oxidation of its components, which generates the loss of nutrients and color, together with the invasion of pathogenic microorganisms. In order to minimize these effects, active packaging has played an important role in preservation in recent years. Therefore, in the present study, an active packaging film was developed using polylactic acid (PLA) and silicon dioxide (SiO2) nanoparticles (NPs) (0.1% w/w) chemically modified with cinnamon essential oil (CEO). For the modification of the NPs, two methods (M1 and M2) were tested, and their effects on the chemical, mechanical, and physical properties of the polymer matrix were evaluated. The results showed that CEO conferred to SiO2 NPs had a high percentage of 2,2-diphenyl-l-picrylhydrazyl (DPPH) free radical inhibition (>70%), cell viability (>80%), and strong inhibition to E. coli, at 45 and 11 µg/mL for M1 and M2, respectively, and thermal stability. Films were prepared with these NPs, and characterizations and evaluations on apple storage were performed for 21 days. The results show that the films with pristine SiO2 improved tensile strength (28.06 MPa), as well as Young's modulus (0.368 MPa) since PLA films only presented values of 27.06 MPa and 0.324 MPa, respectively; however, films with modified NPs decreased tensile strength values (26.22 and 25.13 MPa), but increased elongation at break (from 5.05% to 10.32-8.32%). The water solubility decreased from 15% to 6-8% for the films with NPs, as well as the contact angle, from 90.21° to 73° for the M2 film. The water vapor permeability increased for the M2 film, presenting a value of 9.50 × 10-8 g Pa-1 h-1 m-2. FTIR analysis indicated that the addition of NPs with and without CEO did not modify the molecular structure of pure PLA; however, DSC analysis indicated that the crystallinity of the films was improved. The packaging prepared with M1 (without Tween 80) showed good results at the end of storage: lower values in color difference (5.59), organic acid degradation (0.042), weight loss (24.24%), and pH (4.02), making CEO-SiO2 a good component to produce active packaging.

7.
Biomed Mater Eng ; 34(5): 399-412, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36502300

RESUMO

BACKGROUND: Polymerization conditions affect the physical-mechanical properties of acrylic resins used for craniofacial prostheses. OBJECTIVE: The aim of this study was to evaluate the effect of microwave polymerization on the thermomechanical properties and surface morphology of ocular prostheses fabricated with polymethyl methacrylate (PMMA). METHODS: PMMA discs were polymerized with microwave energy and with conventional heat polymerization (CHP) method. Ocular prostheses were fabricated to determine whether there were changes according to the polymerization method. The surface morphology and roughness were observed under SEM and AFM. The Vickers Hardness number (VHN) and flexural strength were measured. Thermal properties were evaluated with TGA/DSC, and chemical composition with FTIR. RESULTS: The PMMA acrylic resin polymerized with microwave energy showed a smooth surface with some relief areas. In the internal surface of the ocular prosthesis with microwave energy the PMMA is more compact. The mean roughness values were higher and statistically significant with CHP (P < 0.05), while the surface hardness and flexural strength were higher with microwave energy (P < 0.05). CONCLUSION: There were no changes in the calorimetry with either method, TGA showed an exothermic peak around 120 °C with CHP method. PMMA polymerized with microwave energy improved the mechanical and surface properties of the ocular prostheses.


Assuntos
Resinas Acrílicas , Polimetil Metacrilato , Polimetil Metacrilato/química , Polimerização , Resinas Acrílicas/química , Micro-Ondas , Teste de Materiais , Propriedades de Superfície , Dureza , Bases de Dentadura
8.
Crit Rev Food Sci Nutr ; 63(24): 6820-6839, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35170386

RESUMO

Coffee is one of the most consumed beverages in the world. Coffee provides to the consumer special sensorial characteristics, can help to prevent diseases, improves physical performance and increases focus. In contrast, coffee consumption supplies a significant source of substances with carcinogenic and genotoxic potential such as furan, hydroxymethylfurfural (HMF), furfural (F), and acrylamide (AA). The present review addresses the issues around the presence of such toxic substances formed in Maillard reaction (MR) during thermal treatments in food processing, from chemical and, toxicological perspectives, occurrences in coffee and other foods processed by heating. In addition, current strategies advantages and disadvantages are presented along with application of molecular imprinting technology (MIT) and poly (ionic liquid) s (PIL) as an alternative to reduce the furan, HMF, F and AA content in coffee and other foods.


Assuntos
Líquidos Iônicos , Impressão Molecular , Café/química , Líquidos Iônicos/química , Acrilamida/química , Furanos
9.
Rev Int Androl ; 21(1): 100329, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36266232

RESUMO

INTRODUCTION AND OBJECTIVES: Throughout the coronavirus disease 2019 (COVID-19) pandemic, a greater severity and lethality of the disease has been highlighted in male patients, so we set out to evaluate the prognostic role of serum testosterone levels in the clinical results of this population. METHODS: In this single-center and cross-sectional design, we included male patients admitted to our hospital with COVID-19 confirmed diagnosis. The biochemical analysis included lymphocytes, lactate dehydrogenase (LDH), total testosterone (TT), dehydroepiandrosterone, follicle-stimulating hormone, and luteinizing hormone. Receiver operating characteristic curves, univariate and bivariate analysis, and binary logistic regression for multivariate analysis were performed. A p value<0.05 was consider significant. RESULTS: From 86 men included, 48.8% died. TT levels were lower in non-survivor patients than in survivor patients (4.01nmol/L [0.29-14.93] vs 5.41 (0.55-25.08) nmol/L, p=0.021). The independent risk factors that increased the relative risk (RR) of dying from COVID-19 were: age>59 years (RR 3.5 [95% IC 1.0-11.6], p=0.045), TT levels<4.89nmol/L (RR 4.0 [95% IC 1.2-13.5], p=0.027) and LDH levels>597IU/L (RR 3.9 [95% IC 1.2-13.1], p=0.024). Patients who required mechanical ventilation (p=0.025), had lymphopenia (p=0.013) and LDH levels>597IU/L (p=0.034), had significantly lower TT levels compared to those who did not present these conditions. There were no differences in TT levels between patients who had or did not have comorbidities. CONCLUSIONS: A TT level<4.89nmol/L increase four times the RR of death from COVID-19 in men, regardless of age or presence of comorbidities.


Assuntos
COVID-19 , Humanos , Masculino , Pessoa de Meia-Idade , Estudos de Coortes , Estudos Transversais , México , Fatores de Risco , Testosterona
10.
Nanomaterials (Basel) ; 12(24)2022 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-36558257

RESUMO

The internet of medical things (IoMT) is used for the acquisition, processing, transmission, and storage of medical data of patients. The medical information of each patient can be monitored by hospitals, family members, or medical centers, providing real-time data on the health condition of patients. However, the IoMT requires monitoring healthcare devices with features such as being lightweight, having a long lifetime, wearability, flexibility, safe behavior, and a stable electrical performance. For the continuous monitoring of the medical signals of patients, these devices need energy sources with a long lifetime and stable response. For this challenge, conventional batteries have disadvantages due to their limited-service time, considerable weight, and toxic materials. A replacement alternative to conventional batteries can be achieved for piezoelectric and triboelectric nanogenerators. These nanogenerators can convert green energy from various environmental sources (e.g., biomechanical energy, wind, and mechanical vibrations) into electrical energy. Generally, these nanogenerators have simple transduction mechanisms, uncomplicated manufacturing processes, are lightweight, have a long lifetime, and provide high output electrical performance. Thus, the piezoelectric and triboelectric nanogenerators could power future medical devices that monitor and process vital signs of patients. Herein, we review the working principle, materials, fabrication processes, and signal processing components of piezoelectric and triboelectric nanogenerators with potential medical applications. In addition, we discuss the main components and output electrical performance of various nanogenerators applied to the medical sector. Finally, the challenges and perspectives of the design, materials and fabrication process, signal processing, and reliability of nanogenerators are included.

11.
Cureus ; 14(9): e29542, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36312630

RESUMO

Introduction and objectives Type 2 diabetes mellitus (T2DM) has been one of the main risk factors associated with mortality from the coronavirus disease 2019 (COVID-19). Insulin resistance (IR) is a preceding and underlying condition of T2DM, which has been thought that it could increase mortality from COVID-19 since it favors the entry of severe acute respiratory syndrome coronavirus type 2 in the host cell. This article reports a biochemical study that estimated the prevalence of IR in COVID-19 patients and non-diabetic patients without COVID-19 history. It also assesses the prognostic role of IR in the evolution of patients with COVID-19. Materials and methods In this single-center, retrospective and cross-sectional design, we included patients with severe and critical COVID-19 and non-diabetic patients without COVID-19 history. We calculated the Homeostatic Model Assessment Insulin Resistance (HOMA-IR) and defined IR with a HOMA-IR >2.6. We estimated the prevalence of IR in both groups and used x 2 to assess the association between IR and mortality from severe and critical COVID-19. Results One hundred and twenty-three COVID-19 patients were included with a mean age of 53±15 years: 77 (62.6%) were men and 46 (37.4%) were women. Eighty (65%) patients were critical while the rest were severe. Forty-three (35%) patients died. Seventy-one (57.7%) patients had IR; there was no evidence of an association between IR and mortality from severe or critical COVID-19. Fifty-five non-diabetic patients without COVID-19 history were included with a median age of 40 (26-60) years; 35 (63.6%) were men and 20 (36.4%) were women. Nineteen (34.5%) people had IR. Conclusion IR was more prevalent in patients with severe and critical COVID-19 than in non-diabetic patients without COVID-19 history. Our results showed no evidence of the association between IR and mortality from severe and critical COVID-19.

12.
Artigo em Inglês | MEDLINE | ID: mdl-35805345

RESUMO

The COVID-19 pandemic has affected educational institutions around the world. One partial solution for students and teachers to continue the academic process involved the use of software and hardware technologies via the internet. The main objective of this research was to analyze the actions carried out by computer science teachers (and teachers who taught related degrees) in Sinaloa, Mexico, during the COVID-19 confinement period, to determine if the working conditions were different at all educational institutions. Based on quantitative, descriptive-explanatory, correlational, field, and cross-sectional approaches to data collection-a survey was designed and sent to teachers who taught classes in computer science and related careers. The results showed that although teachers felt prepared in designing and implementing virtual courses (90.73%), 68.5% believed that virtual classes were not enough for students (i.e., regarding replacing the training being offered). Likewise, teachers observed that only 27.8% of their students showed real commitment to online classes. In the hypothesis test, a chi-squared value of 3.84 was obtained, with a significance (p-value) of 0.137. There was a probability of error of 13.7%; this is high, considering that the level of significance must be 0.05 (5%) or less. It was concluded that teachers must be permanently trained in the use of new digital technologies; in addition, they must continuously produce academic material and make it available to the educational community. It is necessary for universities to design plans for the regulated use of applications and devices for academic purposes, update study plans and programs, and train teachers and students beyond conventional education.


Assuntos
COVID-19 , COVID-19/epidemiologia , Estudos Transversais , Humanos , Pandemias , Estudantes , Universidades
13.
Magn Reson Imaging ; 93: 62-72, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35842196

RESUMO

BACKGROUND AND AIMS: Chronic heart failure (CHF) represents a significant cause of morbidity and mortality globally. Metabolic maladaptation has proven to be critical in the progression of this condition. Preclinical studies have shown that irisin, an adipomyokine involved in metabolic regulations, can induce positive cardioprotective effects by improving cardiac remodeling, cardiomyocyte viability, calcium delivery, and reducing inflammatory mediators. However, data on clinical studies identifying the associations between irisin levels and functional imaging parameters are scarce in CHF patients. The objective of this study was to determine the association of irisin levels with cardiac imaging measurements through cardiac magnetic resonance, inflammatory markers, and biochemical parameters in patients with CHF compared with control subjects. METHODS AND RESULTS: Thirty-two subjects diagnosed with CHF and thirty-two healthy controls were evaluated in a cross-sectional study. Serum irisin levels were significantly lower in patients with CHF than in controls. This is the first study to report a significant positive correlation between irisin levels and cardiac magnetic resonance parameters such as left ventricular ejection fraction, fraction shortening, and global radial strain. A negative correlation was demonstrated between irisin levels and brain natriuretic peptide, insulin levels, and Homeostatic model assessment for insulin resistance index. We did not observe significant correlations between irisin levels and inflammatory cytokines. CONCLUSIONS: Given the importance of fraction shortening and global radial strain as accurate markers of ventricular wall motion, these results support the hypothesis that irisin may play an essential role in maintaining an adequate myocardial wall architecture, deformation, and thickness.


Assuntos
Fibronectinas , Insuficiência Cardíaca , Biomarcadores , Estudos Transversais , Fibronectinas/sangue , Insuficiência Cardíaca/diagnóstico por imagem , Humanos , Espectroscopia de Ressonância Magnética , Volume Sistólico , Função Ventricular Esquerda
14.
Materials (Basel) ; 15(7)2022 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-35407744

RESUMO

In the present work, LaNi0.5Ti0.5O3 and La2NiTiO6 nanoparticles were synthesized by the modified Pechini method. LaNi0.5Ti0.5O3 was calcined at 1073 K for 17 h or 100 h, while La2NiTiO6 was calcined at 1273 K for 135 h. The double perovskite calcined at 1073 K for 17 h presented orthorhombic symmetry with Pbnm space group, mean particle size was 31.9 ± 1 nm, random ordering of Ni2+ and Ti4+ cations, Néel temperature close to 15 K, and magnetic moment of 1.29 µB. By increasing the calcination time, this material showed the same symmetry and space group, a mean particle size of 50.7 ± 2 nm, short-range ordering of Ni2+ and Ti4+ cations, Néel temperature around 12 K, and magnetic moment of 0.96 µB. La2NiTiO6 presented a monoclinic crystal structure, with P21/n space group, mean particle size of 80.0 ± 5 nm, rock salt ordering of Ni2+ and Ti4+, Néel temperature of approximately 23 K, and magnetic moment of 2.75 µB.

15.
Metab Syndr Relat Disord ; 20(3): 174-181, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35073186

RESUMO

Background: This study provides a clinical model to identify children with insulin resistance (IR) in health care units where laboratory tests are not readily available. Methods: A retrospective study of Mexican children aged 2-16 years at an obesity (OB) clinic. A receiver operating characteristic (ROC) curve was used to assess the accuracy of the proposed model consisting of clinical parameters and to establish the cutoff value for the variables (439 children). A second cohort of children with similar characteristics served as the cohort for the validation of the model (577 children). Results: To determine the best model for predicting IR, we performed a multivariate logistic regression analysis, which showed that waist circumference, acanthosis nigricans, and pubertal status are independent predictors of IR, and when integrated, their predictive power increases. Based on this model, we constructed a simplified equation. The predictive tool was constructed using an ROC curve, with an area under the curve of 0.849. A cutoff value of 7.68 was selected based on the Youden Index, with sensitivity and specificity of 78.3% and 83.3%, respectively. Incorporating metabolic laboratory determinations with a cutoff value of 20.64 improved the sensitivity to 94.9%. Conclusions: We developed a simple and affordable method of identifying IR in children with overweight or OB based on anthropometric variables and routine blood tests for metabolic indicators, such as glucose and triglycerides, which can be implemented in underserved sites.


Assuntos
Resistência à Insulina , Índice de Massa Corporal , Criança , Estudos Transversais , Humanos , México/epidemiologia , Obesidade/diagnóstico , Obesidade/epidemiologia , Sobrepeso/diagnóstico , Sobrepeso/epidemiologia , Curva ROC , Estudos Retrospectivos
16.
Cir Cir ; 89(S2): 38-40, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34932537

RESUMO

Paraclinoid aneurysms take importance due to the technical difficulty due to anatomical relationships, which is why different approaches have been sought for their proper management. This is a female patient with a finding of a paraclinoid aneurysm and treatment using an endonasal approach with adequate angiographic support. Knowledge of the anatomy and surgical skill are required for the management of these lesions, assisted by angiographic controls for successful treatment. The endoscopic endonasal approach is adequate if the anatomy allows it and the basic hospital infrastructure is available to obtain high success rates.


Los aneurismas paraclinoideos cobran importancia debido a la dificultad técnica por sus relaciones anatómicas, por lo que se han buscado diferentes abordajes para su adecuado manejo. Se presenta el caso de una paciente con un aneurisma paraclinoideo y tratamiento mediante abordaje endonasal con apoyo angiográfico adecuado. Se requieren conocimientos de la anatomía y habilidad quirúrgica para el manejo de estas lesiones, así como asistencia de controles angiográficos para el éxito del tratamiento. El abordaje endonasal endoscópico es adecuado en caso de que la anatomía lo permita y se tenga la infraestructura hospitalaria básica para obtener un alto índice de éxitos.


Assuntos
Aneurisma Intracraniano , Angiografia , Feminino , Humanos , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/cirurgia , México , Microcirurgia , Procedimentos Neurocirúrgicos
17.
Mar Environ Res ; 172: 105501, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34656017

RESUMO

Intertidal seagrasses are subjected to desiccation and direct solar radiation during low tides. It is assumed that the canopy structure can self-protect the underlying shoots during these events, although there is no evidence on a physiological basis. The physiological responses of the surfgrass Phyllospadix torreyi were examined when emerged during low tide, on i) shoots overlaying the canopy, and ii) shoots sheltered within the canopy. Leaf water potential and water content decreased in external leaves after emersion, and the higher concentration of organic osmolytes reflected osmoregulation. Additionally, these shoots also exhibited a drastic reduction in carbohydrates after re-immersion, likely from cellular damage. Lipid peroxidation and antioxidant activity increments were also detected, while photosynthetic efficiency strongly diminished from direct exposure to solar radiation. Conversely, the sheltered shoots did not dehydrate and solely accumulated some oxidative stress, likely resulting from the warming of the canopy. In conclusion, the leaf canopy structure buffers physiological stress in the sheltered shoots, thus acting as a self-protective mechanism to cope with emersion.


Assuntos
Zosteraceae , Fotossíntese , Folhas de Planta , Estresse Fisiológico , Água
18.
Sci Rep ; 11(1): 12127, 2021 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-34108550

RESUMO

Bariatric and metabolic surgery has shown to promote weight loss and reduce systemic inflammation. However, the sequence and timing of events regarding metabolic improvement and inflammation resolution has been rarely explored. Furthermore, data on inflammatory markers of Th17 and Th1 cell responses after bariatric surgery is scarce. We conducted a prospective study in subjects with obesity that underwent bariatric and metabolic surgery, with follow-ups at 3 and 6 months. Anthropometric and metabolic markers such as insulin levels, HOMA-IR, and lipid parameters declined significantly 3 months after surgery; while hs-CRP, TNF-α, IL-1ß, IL-6, and IL-8 serum concentrations decreased 6 months after the procedure. Concentrations of Th1 signature and driver cytokines, particularly IFN-γ, IL-12, and IL-18, and of Th17 driver IL-23 also decreased significantly after 6 months. Significant positive correlations between triglyceride levels and hs-CRP, IL-1ß, and IFN-γ concentrations, and between Apo B and IFN-γ levels were observed 6 months after bariatric and metabolic surgery. In addition, BMI was associated with hs-CRP and TNF-α concentrations. Fat mass correlated with hs-CRP, TNF-α, and IL-12. Analysis of the temporality of metabolic and inflammatory events suggests that improvement in the metabolic status occurs before resolution of systemic inflammation and may be a requisite for the later event.


Assuntos
Cirurgia Bariátrica/métodos , Bariatria/métodos , Biomarcadores/sangue , Inflamação/prevenção & controle , Obesidade/cirurgia , Adulto , Citocinas/sangue , Feminino , Humanos , Inflamação/metabolismo , Inflamação/patologia , Resistência à Insulina , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
19.
FEMS Microbiol Lett ; 368(8)2021 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-33956121

RESUMO

Mycetoma is a chronic human infectious disease that produces severe deformation frequently in the lower extremities. Etiological agents include fungi (eumycetoma) and bacteria (actinomycetoma) that produce similar clinical and microscopic changes. The clinical appearance includes swelling, abscesses, ulcers, scars and sinuses that drain purulent material with microbe microcolonies. The pathogenesis of actinomycetoma has been studied mainly in rodents. Using this approach, it was found that Nocardia brasiliensis produces proteases that may play a role in tissue damage, as well as immunosuppressive molecules, such as brasilicardin A. Nitric oxide (NO) is a molecule with biological activities depending on its local concentration. Its effect on killing intracellular bacteria such as Mycobacterium tuberculosis has been known for decades. NO plays an important role in innate and adaptive immunity. It can promote or suppress some biological activities despite its short half-ife. NO is produced by three different nitric oxide synthases (NOS). We used the genetic blockade of eNOS in C57BL/6 mice to demonstrate the role of NO in actinomycetoma development. Inflammation and actinomycetoma were prevented in genetically modified mice infected with N. brasiliensis. T cell proliferation was increased in these rodents, and antibody production, IL-6 and IL-10 expression were similar and TNF-α was lower.


Assuntos
Micetoma/imunologia , Óxido Nítrico Sintase Tipo III/genética , Óxido Nítrico/imunologia , Nocardia , Animais , Citocinas/imunologia , Feminino , Ativação Linfocitária , Camundongos Endogâmicos C57BL , Camundongos Knockout , Micetoma/microbiologia , Linfócitos T/imunologia
20.
Pediatr. (Asunción) ; 48(1)abr. 2021.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1386662

RESUMO

RESUMEN Los linfangiomas abdominales son tumores quísticos poco frecuentes en pediatría, representan el 1% de todos los casos de linfangiomas; los síntomas clínicos no son específicos, se descubren de forma incidental; actualmente el manejo quirúrgico es de primera elección, pero se deben valorar otras posibilidades terapéuticas como los agentes esclerosantes que, dependiendo del tamaño, la ausencia o no de sintomatología y las comorbilidades del paciente se convierte en otra opción terapéutica menos invasivo con el cual se logran buenos resultados; se describe los casos clínicos de dos neonatos con diagnóstico de linfangioma retroperitoneal, manejados con agentes esclerosantes (caso 1) y cirugía (caso 2), mostrando las diferentes opciones terapéuticas.


ABSTRACT Abdominal lymphangiomas are infrequent cystic tumors in pediatric patients, they represent 1% of all cases of lymphangiomas; clinical symptoms are not specific, they are usually discovered incidentally; Surgical management is currently the first-line treatment, but other therapeutic possibilities, such as sclerosing agents, must be evaluated. Depending on the size, the presence or not of symptoms and the patient's comorbidities, these alternatives become another less-invasive therapeutic option, with which good results may be achieved. Two clinical cases of neonates diagnosed with retroperitoneal lymphangioma are described, one was managed with sclerosing agents and the other with surgery, exemplifying different therapeutic options.

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