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1.
Braz J Biol ; 84: e282664, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39109724

RESUMO

In the last few years, there has been an increasing interest in solutions for sustainable agriculture to reduce negative impacts on the environment resulting from modern agricultural practices. The use of environmentally beneficial bacteria, like Pseudomonas, which can increase plant productivity by reducing growth time, is a promising opportunity for sustainable agriculture. Pseudomonas is a gram-negative bacterium genus, commonly present in soils, plants, and irrigation water. Pseudomonas has a wide range of metabolic routes that could benefit agriculture, such as nutrient uptake, pathogen suppression, heavy metal solubilization, drought tolerance, and high salt concentration tolerance. Pseudomonas may even be proposed as a potential tool for future agriculture on other planets, where the use of microorganisms would be essential for crop development in hostile and inhospitable environments. Hence, the present review discusses the potential use of Pseudomonas in sustainable agriculture on planet Earth and potentially on Mars, highlighting its role in plant growth enhancement and plant protection from pathogenic microorganisms.


Assuntos
Agricultura , Pseudomonas , Pseudomonas/fisiologia , Microbiologia do Solo , Desenvolvimento Vegetal/fisiologia
2.
Mol Divers ; 2024 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-39153018

RESUMO

Diet habits and nutrition quality significantly impact health and disease. Here is delve into the intricate relationship between diet habits, nutrition quality, and their direct impact on health and homeostasis. Focusing on (-)-Epicatechin, a natural flavanol found in various foods like green tea and cocoa, known for its positive effects on cardiovascular health and diabetes prevention. The investigation encompasses the absorption, metabolism, and distribution of (-)-Epicatechin in the human body, revealing a diverse array of metabolites in the circulatory system. Notably, (-)-Epicatechin demonstrates an ability to activate nitric oxide synthase (eNOS) through the G protein-coupled estrogen receptor (GPER). While the precise role of GPER and its interaction with classical estrogen receptors (ERs) remains under scrutiny, the study employs computational methods, including density functional theory, molecular docking, and molecular dynamics simulations, to assess the physicochemical properties and binding affinities of key (-)-Epicatechin metabolites with GPER. DFT analysis revealed distinct physicochemical properties among metabolites, influencing their reactivity and stability. Rigid and flexible molecular docking demonstrated varying binding affinities, with some metabolites surpassing (-)-Epicatechin. Molecular dynamics simulations highlighted potential binding pose variations, while MMGBSA analysis provided insights into the energetics of GPER-metabolite interactions. The outcomes elucidate distinct interactions, providing insights into potential molecular mechanisms underlying the effects of (-)-Epicatechin across varied biological contexts.

3.
Rev Gastroenterol Mex (Engl Ed) ; 89(3): 418-441, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39003101

RESUMO

INTRODUCTION: Management of the patient with cirrhosis of the liver that requires surgical treatment has been relatively unexplored. In Mexico, there is currently no formal stance or expert recommendations to guide clinical decision-making in this context. AIMS: The present position paper reviews the existing evidence on risks, prognoses, precautions, special care, and specific management or procedures for patients with cirrhosis that require surgical interventions or invasive procedures. Our aim is to provide recommendations by an expert panel, based on the best published evidence, and consequently ensure timely, quality, efficient, and low-risk care for this specific group of patients. RESULTS: Twenty-seven recommendations were developed that address preoperative considerations, intraoperative settings, and postoperative follow-up and care. CONCLUSIONS: The assessment and care of patients with cirrhosis that require major surgical or invasive procedures should be overseen by a multidisciplinary team that includes the anesthesiologist, hepatologist, gastroenterologist, and clinical nutritionist. With respect to decompensated patients, a nephrology specialist may be required, given that kidney function is also a parameter involved in the prognosis of these patients.


Assuntos
Cirrose Hepática , Assistência Perioperatória , Humanos , Cirrose Hepática/complicações , Cirrose Hepática/cirurgia , Assistência Perioperatória/métodos , Assistência Perioperatória/normas , México , Complicações Pós-Operatórias/prevenção & controle
4.
Phys Chem Chem Phys ; 26(30): 20576-20584, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39037201

RESUMO

The electronic structure and derived optical properties of five synthesized metal-dicyanoaurate(I), (K)M[Au(CN)2], (M = Mn, Co, Ni, Zn and Cd), coordination polymers are described from a combined experimental analysis and theoretical study based on density functional theory. In this sense, the topological features that influence the electronic structure, which in turn give rise to electronic transitions associated with the band gap energy, are studied from first principles calculations (with hybrid HSE06 and GGA-PBE density functionals) and electronic spectroscopy. The impact of gold (through spin-orbit coupling) and aurophilic interactions on the electronic transitions that gives rise to optical properties is described. The calculated projected density of states and band dispersion diagrams shed light on the molecular orbital distribution and the role of a dicyanoaurate(I) molecular block as the origin of the optical properties. Infrared, Raman and ultraviolet-visible spectroscopic analyses reveal the effect that charge transfer interactions, of a metal → ligand and metal → metal nature, have on the electronic behavior within the solids through association with the polarizing power of transition metals and gold atoms.

5.
Surg Neurol Int ; 15: 120, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38741985

RESUMO

Background: Rathke's cleft cyst (RCC) is a benign lesion in the sellar and suprasellar compartments. Similarly, pituitary adenomas can present with cystic morphology, making it a differential diagnosis when evaluating a patient with a cystic lesion in the sellar region. Surgical goals differ between RCCs and pituitary adenomas as the first can achieve remission of symptoms with cyst decompression in contrast to pituitary adenomas where complete resection would be the main goal. Imaging analysis alone may not be sufficient to define a preoperative surgical plan. The combination of imaging and conjoined use of validated tools may provide valuable insights to the clinician when defining a surgical approach. Case Description: We present a case of a 27-year-old male with a 3-month history of visual disturbances and headaches. Magnetic resonance imaging showed a cystic lesion in the sellar compartment with compression of nearby structures. The authors were able to accurately diagnose this sellar lesion as an RCC with the conjoined aid of two classifications proposed in the literature. Cyst evacuation was performed with relief of symptoms and improved visual outcomes at follow-up. Conclusion: While cystic adenomas can require total resection for cure, RCCs can show marked improvement with partial resection and evacuation of its contents. An accurate preoperative diagnosis can lead the surgeon to opt for the best surgical approach.

6.
Rev Gastroenterol Mex (Engl Ed) ; 89(1): 144-162, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38600006

RESUMO

Coagulation management in the patient with cirrhosis has undergone a significant transformation since the beginning of this century, with the concept of a rebalancing between procoagulant and anticoagulant factors. The paradigm that patients with cirrhosis have a greater bleeding tendency has changed, as a result of this rebalancing. In addition, it has brought to light the presence of complications related to thrombotic events in this group of patients. These guidelines detail aspects related to pathophysiologic mechanisms that intervene in the maintenance of hemostasis in the patient with cirrhosis, the relevance of portal hypertension, mechanical factors for the development of bleeding, modifications in the hepatic synthesis of coagulation factors, and the changes in the reticuloendothelial system in acute hepatic decompensation and acute-on-chronic liver failure. They address new aspects related to the hemorrhagic complications in patients with cirrhosis, considering the risk for bleeding during diagnostic or therapeutic procedures, as well as the usefulness of different tools for diagnosing coagulation and recommendations on the pharmacologic treatment and blood-product transfusion in the context of hemorrhage. These guidelines also update the knowledge regarding hypercoagulability in the patient with cirrhosis, as well as the efficacy and safety of treatment with the different anticoagulation regimens. Lastly, they provide recommendations on coagulation management in the context of acute-on-chronic liver failure, acute liver decompensation, and specific aspects related to the patient undergoing liver transplantation.


Assuntos
Insuficiência Hepática Crônica Agudizada , Transtornos da Coagulação Sanguínea , Humanos , Insuficiência Hepática Crônica Agudizada/complicações , Transtornos da Coagulação Sanguínea/complicações , Transtornos da Coagulação Sanguínea/terapia , Cirrose Hepática/complicações , Cirrose Hepática/terapia , Coagulação Sanguínea , Hemostasia
7.
Rev Esp Anestesiol Reanim (Engl Ed) ; 71(5): 394-402, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38588770

RESUMO

OBJECTIVE: To identify the first symptoms and signs of patients with suspected infection or sepsis and their association with the composite outcome of admission to the Intensive Care Unit (ICU) or mortality. DESIGN: Prospective cohort study between June 2019 and March 2020. SETTING: Hospital Universitario San Vicente Fundación, Colombia. PATIENTS: Over 18 years of age with suspicion or confirmation of sepsis, which required hospitalization. INTERVENTIONS: None. MAIN VARIABLES OF INTEREST: Symptoms and signs associated with infection, with their time of evolution, specified in the study. RESULTS: From 1005 eligible patients, 261 were included. After multivariable adjustment with a logistic regression model, the main factors for ICU admission or mortality were heart rate (OR 1.04 with 95% CI 1.04-3.7), respiratory rate (OR 1.19 with 95% CI 1.0-1.4) and capillary refill time (OR 3.4 with 95% CI 1.9-6.1). CONCLUSIONS: Heart rate, respiratory rate, and capillary refill may behave as early predictors of ICU admission and mortality in cases of sepsis.


Assuntos
Unidades de Terapia Intensiva , Sepse , Humanos , Sepse/mortalidade , Colômbia/epidemiologia , Masculino , Estudos Prospectivos , Feminino , Pessoa de Meia-Idade , Prognóstico , Idoso , Mortalidade Hospitalar , Frequência Cardíaca , Taxa Respiratória , Infecções/complicações , Adulto
8.
Photochem Photobiol Sci ; 23(5): 901-918, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38584224

RESUMO

Pd/ZnO nanocomposites were successfully synthesized by means of one and two pot synthesis and applied in the photodegradation of Rh6G. The nanocomposites were characterized by XRD, SEM, TEM, FTIR and micro-Raman spectroscopies. It was found the presence of PdZn2, PdO and agglomerated particles in the support surface for the Palladium-based nanocomposites fabricated by one-pot route; the two-step method allowed the formation of spherical Pd nanoparticles, with homogeneous distribution in the nanocomposite matrix, with an average size of 2.16 nm. The results show higher photocatalytic efficiency for the samples fabricated under the two-step approach compared to the one-pot synthesis. Based on experimental results, density functional theory (DFT) calculations were carried out to understand the enhancement photocatalytic of Pd/ZnO nanocomposites. To achieve it, the ZnO (001) and (101) surfaces were built and decorated by different Pd coverages. The theoretical results indicated two different photocatalytic mechanisms. In ZnO (001) case, the electrons flowed from surface to Pd, generating the superoxide radical anion (⋅O2-). Furthermore, the density of states of the ZnO (001) surface was modified by impurity Pd-d states at proximity to the conduction states, which may work as electron acceptors states. On the other hand, we found that the electrons flow from Pd to ZnO (101) surface, inducing the formation of ⋅OH and ⋅O2- for the degradation of Rh6G. The density of states of the ZnO (101) revealed a reduction in its bandgap, due to Pd-d states localized above valence states. Hence, our theoretical results suggest that the Pd-d states may facilitate the mobility of electrons and holes in (001) and (101) surfaces, respectively, reducing the rate of charge recombination.

9.
PLoS One ; 19(1): e0297061, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38285702

RESUMO

A chain formation strategy based on mobile frames for a set of n differential drive mobile robots is presented. Considering two consecutive robots in the formation, robots Ri and Ri+1. It is intended that robot Ri+1 follows the delayed trajectory, τ units of time, of the leader robot Ri. In this way, the follower robot Ri+1 becomes the leader robot for robot Ri+ 2 in the formation and so on. With this formation policy, the trailing distance between two consecutive robots varies accordingly to the velocity of the Ri leader robot. Mobile frames are located on the body of the vehicles, in such a way that the position of robot Ri is determined with respect to the frame located on Ri+1 robot. The strategy relies on the fact that the general leader robot R1 describes any trajectory generated by bounded linear v1(t) and angular ω1(t) velocities. For the remaining vehicles in the string, the strategy considers a desired trajectory for the follower robot Ri+1 obtained by an estimation of the delayed trajectory of the leader robot Ri. This desired estimated trajectory is obtained under the knowledge of the actual and past input velocities of the Ri robot. To formally prove the convergence of the formation strategy, the equations describing the time variation of the relative posture between any pair of consecutive vehicles in the formation are obtained, and a feedback law based on local measurements is proposed to get the convergence of robot Ri+1 to the delayed trajectory, τ units of time, of the trajectory previously described by robot Ri. Lyapunov techniques are considered for this fact. The effectiveness of the chain formation solution is evaluated by means of numerical simulations and real time experiments showing an adequate convergence.


Assuntos
Robótica , Conhecimento , Políticas , Postura , Fases de Leitura
10.
Early Hum Dev ; 189: 105945, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38271767

RESUMO

Breastfeeding is recognized worldwide as the best option for infant feeding. Expressing breast milk is an alternative for mothers to provide their infants all the benefits of maternal milk. During breast milk expression, mothers receive a distinct kind of sensory stimulation, because there is no direct bodily or affective interaction with their infants, many women report feeling isolated, generating a love-hate relation with pumping, and even low levels of satisfaction while expressing breast milk. While it is well known that the prefrontal, parietal, and temporal cortices play important roles in the emotional and cognitive processing of maternal stimuli, knowledge about how these cortical areas function during breastfeeding is lacking. This study was designed to characterize EEG activity in the prefrontal and parietal cortices and the affective scores of primiparous breastfeeding mothers during two conditions of milk expression: breast milk expression and direct breastfeeding. Participants reported higher valence and arousal and a pleasant state during direct breastfeeding. In the direct breastfeeding condition, both prefrontal areas showed a higher absolute power (AP) of the slow bands, with a lower AP of the alpha band in the parietal cortex. A lower correlation between frontopolar and dorsolateral areas with a higher correlation between prefrontal and parietal cortices was obtained mainly in the right hemisphere. This EEG activity could be linked to an internal state of focused attention and, simultaneously, open monitoring of the environment that suggests an integration of the motive-emotional and cognitive processes necessary for adequate mother-baby interaction during direct breastfeeding.


Assuntos
Aleitamento Materno , Extração de Leite , Lactente , Feminino , Humanos , Aleitamento Materno/psicologia , Mães/psicologia , Leite Humano , Eletroencefalografia
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