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1.
Chem Rev ; 124(6): 3392-3415, 2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38466339

RESUMEN

Magnetic ionic liquids (MILs) stand out as a remarkable subclass of ionic liquids (ILs), combining the desirable features of traditional ILs with the unique ability to respond to external magnetic fields. The incorporation of paramagnetic species into their structures endows them with additional attractive features, including thermochromic behavior and luminescence. These exceptional properties position MILs as highly promising materials for diverse applications, such as gas capture, DNA extractions, and sensing technologies. The present Review synthesizes key experimental findings, offering insights into the structural, thermal, magnetic, and optical properties across various MIL families. Special emphasis is placed on unraveling the influence of different paramagnetic species on MILs' behavior and functionality. Additionally, the Review highlights recent advancements in computational approaches applied to MIL research. By leveraging molecular dynamics (MD) simulations and density functional theory (DFT) calculations, these computational techniques have provided invaluable insights into the underlying mechanisms governing MILs' behavior, facilitating accurate property predictions. In conclusion, this Review provides a comprehensive overview of the current state of research on MILs, showcasing their special properties and potential applications while highlighting the indispensable role of computational methods in unraveling the complexities of these intriguing materials. The Review concludes with a forward-looking perspective on the future directions of research in the field of magnetic ionic liquids.

2.
Stroke ; 55(5): 1218-1226, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38572636

RESUMEN

BACKGROUND: Decompressive neurosurgery is recommended for patients with cerebral venous thrombosis (CVT) who have large parenchymal lesions and impending brain herniation. This recommendation is based on limited evidence. We report long-term outcomes of patients with CVT treated by decompressive neurosurgery in an international cohort. METHODS: DECOMPRESS2 (Decompressive Surgery for Patients With Cerebral Venous Thrombosis, Part 2) was a prospective, international cohort study. Consecutive patients with CVT treated by decompressive neurosurgery were evaluated at admission, discharge, 6 months, and 12 months. The primary outcome was death or severe disability (modified Rankin Scale scores, 5-6) at 12 months. The secondary outcomes included patient and caregiver opinions on the benefits of surgery. The association between baseline variables before surgery and the primary outcome was assessed by multivariable logistic regression. RESULTS: A total of 118 patients (80 women; median age, 38 years) were included from 15 centers in 10 countries from December 2011 to December 2019. Surgery (115 craniectomies and 37 hematoma evacuations) was performed within a median of 1 day after diagnosis. At last assessment before surgery, 68 (57.6%) patients were comatose, fixed dilated pupils were found unilaterally in 27 (22.9%) and bilaterally in 9 (7.6%). Twelve-month follow-up data were available for 113 (95.8%) patients. Forty-six (39%) patients were dead or severely disabled (modified Rankin Scale scores, 5-6), of whom 40 (33.9%) patients had died. Forty-two (35.6%) patients were independent (modified Rankin Scale scores, 0-2). Coma (odds ratio, 2.39 [95% CI, 1.03-5.56]) and fixed dilated pupil (odds ratio, 2.22 [95% CI, 0.90-4.92]) were predictors of death or severe disability. Of the survivors, 56 (78.9%) patients and 61 (87.1%) caregivers expressed a positive opinion on surgery. CONCLUSIONS: Two-thirds of patients with severe CVT were alive and more than one-third were independent 1 year after decompressive surgery. Among survivors, surgery was judged as worthwhile by 4 out of 5 patients and caregivers. These results support the recommendation to perform decompressive neurosurgery in patients with CVT with impending brain herniation.

3.
Artículo en Inglés | MEDLINE | ID: mdl-39133335

RESUMEN

The acquisition of an acoustic template is a fundamental component of vocal imitation learning, which is used to refine innate vocalizations and develop a species-specific song. In the absence of a model, birds fail to develop species typical songs. In zebra finches (Taeniopygia guttata), tutored birds produce songs with a stereotyped sequence of distinct acoustic elements, or notes, which form the song motif. Songs of untutored individuals feature atypical acoustic and temporal structure. Here we studied songs and associated respiratory patterns of tutored and untutored male zebra finches to investigate whether similar acoustic notes influence the sequence of song elements. A subgroup of animals developed songs with multiple acoustically similar notes that are produced with alike respiratory motor gestures. These birds also showed increased syntactic variability in their adult motif. Sequence variability tended to occur near song elements which showed high similarity in acoustic structure and underlying respiratory motor gestures. The duration and depth of the inspirations preceding the syllables where syntactic variation occurred did not allow prediction of the following sequence of notes, suggesting that the varying duration and air requirement of the following expiratory pulse is not predictively encoded in the motor program. This study provides a novel method for calculation of motor/acoustic similarity, and the results of this study suggest that the note is a fundamental acoustic unit in the organization of the motif and could play a role in the neural code for song syntax.

4.
Org Biomol Chem ; 22(7): 1500-1513, 2024 02 14.
Artículo en Inglés | MEDLINE | ID: mdl-38294067

RESUMEN

Inspired by the pharmacological interest generated by 6-substituted purine roscovitine for cancer treatment, 5-aminoimidazole-4-carboxamidine precursors containing a cyanamide unit were prepared by condensation of 5-amino-N-cyanoimidazole-4-carbimidoyl cyanides with a wide range of primary amines. When these amidine precursors were combined with acids, a fast cascade cyclization occurred at room temperature, affording new 6,8-diaminopurines with the N-3 and N-6 substituents changed relatively to the original positions they occupied in the amidine and imidazole moieties of precursors. The efficacy and wide scope of this method was well demonstrated by an easy and affordable synthesis of 22 6,8-diaminopurines decorated with a wide diversity of substituents at the N-3 and N-6 positions of the purine ring. Preliminary in silico and in vitro assessments of these 22 compounds were carried out and the results showed that 13 of these tested compounds not only exhibited IC50 values between 1.4 and 7.5 µM against the colorectal cancer cell line HCT116 but also showed better binding energies than known inhibitors in docking studies with different cancer-related target proteins. In addition, good harmonization observed between in silico and in vitro results strengthens and validates this preliminary evaluation, suggesting that these novel entities are good candidates for further studies as new anticancer agents.


Asunto(s)
Antineoplásicos , Estructura Molecular , Relación Estructura-Actividad , Antineoplásicos/química , Ciclización , Imidazoles/farmacología , Purinas/farmacología , Amidinas/farmacología , Línea Celular Tumoral , Simulación del Acoplamiento Molecular , Ensayos de Selección de Medicamentos Antitumorales , Proliferación Celular
5.
Org Biomol Chem ; 22(11): 2252-2263, 2024 03 13.
Artículo en Inglés | MEDLINE | ID: mdl-38390694

RESUMEN

Monitoring cell viability is critical in cell biology, pathology, and drug discovery. Most cell viability assays are cell-destructive, time-consuming, expensive, and/or hazardous. Herein, we present a series of newly synthesized 2,4,5-triaminopyrimidine derivatives able to discriminate between live and dead cells. To our knowledge, these compounds are the first fluorescent nucleobase analogues (FNAs) with cell viability monitoring potential. These new fluorescent molecules are synthesized using highly efficient and cost-effective methods and feature unprecedented photophysical properties (longer absorption and emission wavelengths, environment-sensitive emission, and unprecedented brightness within FNAs). Using a live-dead Saccharomyces cerevisiae cell and theoretical assays, the fluorescent 2,4,5-triaminopyrimidine derivatives were found to specifically accumulate inside dead cells by interacting with dsDNA grooves, thus paving the way for the emergence of novel and safe fluorescent cell viability markers emitting in the blue region. As the majority of commercially available viability dyes emit in the green to red region of the visible spectrum, these novel markers might be useful to meet the needs of blue markers for co-staining combinations.


Asunto(s)
Colorantes Fluorescentes , Microscopía , Supervivencia Celular
6.
Oecologia ; 205(1): 135-147, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38739168

RESUMEN

Animal personality can shape individual's fitness. Yet, the mechanistic relationship by which individual's personality traits lead to variations in fitness remains largely underexplored. Here, we used novel object tests to measure boldness of chick-provisioning Cory's shearwaters (Calonectris borealis) from a coastal colony off west Portugal, and deployed GPS loggers to study their at-sea behaviour and distribution. We then tested whether boldness predicts individual differences in adult's trophic ecology and variations in chick growth, to assess potential implications of personality-specific foraging behaviours. Foraging effort was higher for shyer than for bolder individuals, which, during short forays, exhibited larger foraging ranges, and foraged in regions of higher and more variable bathymetry. This suggests that nearby the colony bolder individuals expanded their foraging area to maximize resource acquisition and increase the probability of foraging success. When endeavouring to longer distances, bolder individuals exhibited comparably shorter foraging ranges and targeted low bathymetry regions, likely with enhanced prey availability, while shyer individuals exhibited much larger foraging ranges indicating greater flexibility when foraging in oceanic realms. Despite such differences between bolder and shyer individuals their isotopic niches were similar. Yet, chicks raised by bolder parents grew at a faster rate than those raised by shyer parents. Together, our results suggest that differences in resource acquisition strategies could play a key role through which individual's boldness may influence breeding performance, even when individuals have similar isotopic preferences.


Asunto(s)
Ecosistema , Animales , Aves , Portugal , Conducta Alimentaria , Conducta Predatoria
7.
Phys Chem Chem Phys ; 26(19): 14393-14406, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38712786

RESUMEN

Smart water injection is a technology that allows changing the wettability of the oil rock by injecting water at different salinities, in a cheap and environmentally friendly way compared to other traditional methods. In this study, the individual effect of some typical salts on the wettability of the (104) surface of calcite toward non-polar and polar crude oil models was explored by molecular dynamics as a function of the salinity and pH. The results obtained show that the electrical double layer plays a principal role in the detachment of crude oil models. The divalent ion salts, i.e., CaCl2, CaSO4, MgCl2, and MgSO4, do not form the electrical double layer on calcite, but salts of NaCl and Na2SO4 form it. Moreover, the surface affinity of calcite to the non-polar crude oil is not affected by the salinity. However, the affinity of the calcite surface toward polar crude is affected by salinity and pH conditions. This research provides new insights into the action mechanisms that could help optimize its uses in enhanced oil recovery.

8.
Biometals ; 37(4): 971-982, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38409305

RESUMEN

The 'sacred leaf' or "Hoja Santa" (Piper auritum Kunth) has a great value for Mexican culture and has gained popularity worldwide for its excellent properties from culinary to remedies. To contribute to its heritage, in this project we proposed the green synthesis of silver oxide nanoparticles (Ag2O NPs) using an extract of "Hoja Santa" (Piper auritum) as a reducing and stabilizing agent. The synthesized Ag2O NPs were characterized by UV-Visible spectroscopy (plasmon located at 405 nm), X-ray diffraction (XRD) (particle size diameter of 10 nm), scanning electron microscopy (SEM) (particle size diameter of 13.62 ± 4.61 nm), and Fourier-transform infrared spectroscopy (FTIR) (functional groups from "Hoja Santa" attached to nanoparticles). Antioxidant capacity was evaluated using DPPH, ABTS and FRAP methods. Furthermore, the antimicrobial activity of NPs against a panel of clinically relevant bacterial strains, including both Gram-positive (Staphylococcus aureus) and Gram-negative bacteria (Salmonella Enteritidis and Escherichia coli O157:H7), was over 90% at concentrations of 200 µg/mL. Additionally, we assessed the antibiofilm activity of the NPs against Pseudomonas aeruginosa (reaching 98% of biofilm destruction at 800 µg/mL), as biofilm formation plays a crucial role in bacterial resistance and chronic infections. Moreover, we investigated the impact of Ag2O NPs on immune cell viability, respiratory burst, and phagocytic activity to understand their effects on the immune system.


Asunto(s)
Antibacterianos , Nanopartículas del Metal , Pruebas de Sensibilidad Microbiana , Piper , Extractos Vegetales , Compuestos de Plata , Staphylococcus aureus , Extractos Vegetales/química , Extractos Vegetales/farmacología , Antibacterianos/farmacología , Antibacterianos/química , Antibacterianos/síntesis química , Compuestos de Plata/química , Compuestos de Plata/farmacología , Staphylococcus aureus/efectos de los fármacos , Piper/química , Nanopartículas del Metal/química , Óxidos/química , Óxidos/farmacología , Antioxidantes/farmacología , Antioxidantes/química , Antioxidantes/síntesis química , Animales , Ratones , Salmonella enteritidis/efectos de los fármacos , Tamaño de la Partícula , Células RAW 264.7 , Escherichia coli O157/efectos de los fármacos , Hojas de la Planta/química
9.
Int J Gynecol Cancer ; 2024 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-39153831

RESUMEN

OBJECTIVE: Management of endometrial cancer is advancing, with accurate staging crucial for guiding treatment decisions. Understanding sentinel lymph node (SLN) involvement rates across molecular subgroups is essential. To evaluate SLN involvement in early-stage (International Federation of Gynecology and Obstetrics 2009 I-II) endometrial cancer, considering molecular subtypes and new European Society of Gynaecological Oncology (ESGO) risk classification. METHODS: The SENECA study retrospectively reviewed data from 2139 women with stage I-II endometrial cancer across 66 centers in 16 countries. Patients underwent surgery with SLN assessment following ESGO guidelines between January 2021 and December 2022. Molecular analysis was performed on pre-operative biopsies or hysterectomy specimens. RESULTS: Among the 2139 patients, the molecular subgroups were as follows: 272 (12.7%) p53 abnormal (p53abn, 1191 (55.7%) non-specific molecular profile (NSMP), 581 (27.2%) mismatch repair deficient (MMRd), 95 (4.4%) POLE mutated (POLE-mut). Tracer diffusion was detected in, at least one side, in 97.2% of the cases; with a bilateral diffusion observed in 82.7% of the cases. By ultrastaging (90.7% of the cases) or one-step nucleic acid amplification (198 (9.3%) of the cases), 205 patients were identified with affected sentinel lymph nodes, representing 9.6% of the sample. Of these, 139 (67.8%) had low-volume metastases (including micrometastases, 42.9%; and isolated tumor cells, 24.9%) while 66 (32.2%) had macrometastases. Significant differences in SLN involvement were observed between molecular subtypes, with p53abn and MMRd groups having the highest rates (12.50% and 12.40%, respectively) compared with NSMP (7.80%) and POLE-mut (6.30%), (p=0.004); (p53abn, OR=1.69 (95% CI 1.11 to 2.56), p=0.014; MMRd, OR=1.67 (95% CI 1.21 to 2.31), p=0.002). Differences were also noted among ESGO risk groups (2.84% for low-risk patients, 6.62% for intermediate-risk patients, 21.63% for high-intermediate risk patients, and 22.51% for high-risk patients; p<0.001). CONCLUSIONS: Our study reveals significant differences in SLN involvement among patients with early-stage endometrial cancer based on molecular subtypes. This underscores the importance of considering molecular characteristics for accurate staging and optimal management decisions.

10.
J Fish Biol ; 104(6): 1875-1887, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38501373

RESUMEN

The short-tail yellownose skate, Zearaja brevicaudata, occurs off southern Brazil and along the Argentine continental shelf, including waters surrounding the Islas Malvinas and the upper slope, and is very frequently caught by trawl fisheries throughout its range. The age, growth, and maturity of Z. brevicaudata were investigated using 204 individuals collected by commercial fishing vessels from northern Argentina, between March 2016 and September 2019. Age was determined on a sample comprising vertebrae from 151 individuals, 60 males, ranging in size from 391 to 956 mm total length (TL), and 91 females, ranging in size from 324 to 1060 mm TL. Maximum ages determined for males and females were 22 and 29 years, respectively. A Bayesian framework was employed with a set of three candidate models to estimate growth parameters (von Bertalanffy, Gompertz, and Logistic). The von Bertalanffy model had the best fit, and the sexes showed undistinguishable growth parameters. For sexes combined, derived growth mean parameters (± S.D.) were L∞ = 1081 mm ± 64.34 mm, k = 0.09 ± 0.01 years-1, and L0 = 248 mm ± 23.52 mm. The age at maturity was estimated at 13.15 and 14.66 years for males and females, respectively.


Asunto(s)
Rajidae , Animales , Rajidae/crecimiento & desarrollo , Masculino , Femenino , Argentina , Rasgos de la Historia de Vida , Explotaciones Pesqueras , Teorema de Bayes , Brasil , Maduración Sexual , Tamaño Corporal
11.
Int J Mol Sci ; 25(4)2024 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-38397123

RESUMEN

Previous data indicate a role of IL-1 and IL-1RA imbalance in bladder carcinoma (BC); the inhibition of IL-1 signaling might be considered a treatment option. Objective: To assess expression patterns and the prognostic role of IL-1ß and IL-1RA in invasive BC and to evaluate their interaction with AKT signaling and proliferation. The study included two independent cohorts of n = 92 and n = 102 patients who underwent a radical cystectomy for BC. Specimen from BC and benign urothelium (n = 22 and n = 39) were processed to a tissue microarray and immunohistochemically stained for IL-1ß, IL-1RA, AKT, and Ki-67. Expression scores were correlated to clinical variables and Ki-67 and AKT expression. An association with outcome was assessed using Wilcoxon Kruskal-Wallis tests, Chi-square tests or linear regression, dependent on the variable's category. Kaplan-Meier and Cox proportional hazard analyses were used to estimate recurrence-free (RFS), cancer-specific (CSS) and overall survival (OS). Both IL-1ß and IL-1RA were significantly overexpressed in invasive BC compared to benign urothelium in both cohorts (p < 0.005). IL-1ß was associated with vascular invasion (210 vs. 183, p < 0.02), lymphatic invasion (210 vs. 180, <0.05) and G3 cancer (192 vs. 188, <0.04). The survival analysis revealed favorable RFS, CSS, and OS in the case of high IL-1ß expression (p < 0.02, <0.03, and <0.006, respectively). Multivariate analyses revealed an independent impact of (low) IL1ß expression on RFS, CSS, and OS. The IL-1ß and IL-1ß/IL-1RA ratios were positively correlated to the AKT expression (p < 0.05 and <0.01, respectively). Additionally, the high expression of Ki-67 (>15%) correlated with higher levels of IL-1ß (p = 0.01). The overexpression of IL-1ß and IL-1RA is frequently found in BC, with a prognostic significance observed for the IL-1ß protein expression. The observed link between the IL-1ß/IL-1RA axis and AKT signaling may indicate possible autophagy activation processes besides the known tumor-promoting effects of AKT.


Asunto(s)
Proteína Antagonista del Receptor de Interleucina 1 , Neoplasias de la Vejiga Urinaria , Humanos , Interleucina-1beta/metabolismo , Antígeno Ki-67 , Proteínas Proto-Oncogénicas c-akt , Neoplasias de la Vejiga Urinaria/patología
12.
Int J Mol Sci ; 25(3)2024 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-38338894

RESUMEN

This review focuses on the role of small extracellular vesicles in the pathophysiological mechanisms of retinal degenerative diseases. Many of these mechanisms are related to or modulated by the oxidative burden of retinal cells. It has been recently demonstrated that cellular communication in the retina involves extracellular vesicles and that their rate of release and cargo features might be affected by the cellular environment, and in some instances, they might also be mediated by autophagy. The fate of these vesicles is diverse: they could end up in circulation being used as markers, or target neighbor cells modulating gene and protein expression, or eventually, in angiogenesis. Neovascularization in the retina promotes vision loss in diseases such as diabetic retinopathy and age-related macular degeneration. The importance of micro RNAs, either as small extracellular vesicles' cargo or free circulating, in the regulation of retinal angiogenesis is also discussed.


Asunto(s)
Vesículas Extracelulares , MicroARNs , Degeneración Retiniana , Humanos , Retina/metabolismo , Degeneración Retiniana/metabolismo , Vesículas Extracelulares/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Estrés Oxidativo
13.
Int J Mol Sci ; 25(2)2024 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-38256008

RESUMEN

Exosomes or small extracellular vesicles (sEVs) represent a pivotal component in intercellular communication, carrying a diverse array of biomolecules. Several factors can affect sEVs release dynamics, as occurs in hyperglycemia or inflammation. In fact, sEVs release has been associated with the promotion of physio-pathological processes. Among the sEVs cargo, microRNAs play an essential role in cell-to-cell regulation. More concretely, miR-205-5p is related to angiogenesis and cell proliferation. The aim of this study is to understand the specific role of sEVs containing miR-205-5p under high glucose conditions. ARPE-19 cells were cultured with high glucose (HG) for 5 days. sEVs were isolated and characterized. sEVs from ARPE-19 were used for angiogenesis and cell proliferation. HG increased sEVs release but downregulated miR-205-5p cargo expression compared to the control. sEVs from HG-treated ARPE-19 cells promoted tube formation and migration processes. In contrast, miR-205-5p overexpression (by mimic transfection) decreased angiogenesis and cell migration. Our results demonstrate how ARPE-19 cells respond to HG challenge by increasing sEVs with weak miR-205-5p cargo. The absence of this miRNA in sEVs is enough to promote angiogenesis. In contrast, restoring sEVs-miR-205-5p levels decreased it. These findings open new possibilities in sEVs-based therapies containing miR-205-5p against angiogenesis.


Asunto(s)
Angiogénesis , MicroARNs , Comunicación Celular , Movimiento Celular/genética , MicroARNs/genética , Glucosa
14.
Molecules ; 29(8)2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38675580

RESUMEN

The presence of antibiotics in soils is increasing drastically in last decades due to the intensive farming industry and excessive human consumption. Clay minerals are one of the soil components with great adsorption capacity for organic pollutants. The study of interactions between antibiotics and mineral surfaces will give us scientific knowledge of these pollutants through soils. In this work, we study the adsorption of the antibiotic ciprofloxacin in the clay mineral fraction of soils from the Argentinian zone of Santa Rosa (Corrientes), in a collaborative research of experiments and atomistic modelling calculations of the intercalation of ciprofloxacin in the interlayer space of montmorillonite. Adsorption and desorption isotherms were performed and compared with different isotherm models. Additionally, enthalpy, entropy, and free energy were determined from equilibrium constants at a function of temperature. All these experiments and calculations lead to the conclusions that two adsorption types of ciprofloxacin are found on clay minerals: one weakly sorbed that is released during the desorption experiments, and other one strongly joined that remains in the soil.

15.
Molecules ; 29(14)2024 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-39064853

RESUMEN

Tetroxane derivatives are interesting drugs for antileishmaniasis and antimalaric treatments. The gas-phase thermal decomposition of 3,6,-dimethyl-1,2,4,5-tetroxane (DMT) and 3,3,6,6,-tetramethyl-1,2,4,5-tetroxane (acetone diperoxide (ACDP)) was studied at 493-543 K by direct gas chromatography by means of a flow reactor. The reaction is produced in the injector chamber at different temperatures. The resulting kinetics Arrhenius equations were calculated for both tetroxanes. Including the parent compound of the series 1,2,4,5-tetroxane (formaldehyde diperoxide (FDP)), the activation energy and frequency factors decrease linearly with the number of methyl groups. The reaction mechanisms of ACDP and 3,6,6-trimethyl-1,2,4,5-tetroxane (TMT) decomposition have been studied by means of the DFT method with the BHANDHLYP functional. Our calculations confirm that the concerted mechanism should be discarded and that only the stepwise mechanism occurs. The critical points of the singlet and triplet state potential energy surfaces (S- and T-PES) of the thermolysis reaction of both compounds have been determined. The calculated activation energies of the different steps vary linearly with the number of methyl groups of the methyl-tetroxanes series. The mechanism for the S-PES leads to a diradical O···O open structure, which leads to a C···O dissociation in the second step and the production of the first acetaldehyde/acetone molecule. This last one yields a second C···O dissociation, producing O2 and another acetone/acetaldehyde molecule. The O2 molecule is in the singlet state. A quasi-parallel mechanism for the T-PES from the open diradical to products is also found. Most of the critical points of both PES are linear with the number of methyl groups. Reaction in the triplet state is much more exothermic than the singlet state mechanism. Transitions from the singlet ground state, S0 and low-lying singlet states S1-3, to the low-lying triplet excited states, T1-4, (chemical excitation) in the family of methyl tetroxanes are also studied at the CASSCF/CASPT2 level. Two possible mechanisms are possible here: (i) from S0 to T3 by strong spin orbit coupling (SOC) and subsequent fast internal conversion to the excited T1 state and (ii) from S0 to S2 from internal conversion and subsequent S2 to T1 by SOC. From these experimental and theoretical results, the additivity effect of the methyl groups in the thermolysis reaction of the methyl tetroxane derivatives is clearly highlighted. This information will have a great impact for controlling these processes in the laboratory and chemical industries.

16.
Fish Physiol Biochem ; 50(4): 1429-1443, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38658493

RESUMEN

Thermal variations due to global climate change are expected to modify the distributions of marine ectotherms, with potential pathogen translocations. This is of particular concern at high latitudes where cold-adapted stenothermal fish such as the Notothenioids occur. However, little is known about the combined effects of thermal fluctuations and immune challenges on the balance between cell damage and repair processes in these fish. The aim of this study was to determine the effect of thermal variation on specific genes involved in the ubiquitination and apoptosis pathways in two congeneric Notothenioid species, subjected to simulated bacterial and viral infections. Adult fish of Harpagifer bispinis and Harpagifer antarcticus were collected from Punta Arenas (Chile) and King George Island (Antarctica), respectively, and distributed as follows: injected with PBS (control), LPS (2.5 mg/kg) or Poly I:C (2 mg/kg) and then submitted to 2, 5 and 8 °C. After 1 week, samples of gills, liver and spleen were taken to evaluate the expression by real-time PCR of specific genes involved in ubiquitination (E3-ligase enzyme) and apoptosis (BAX and SMAC/DIABLO). Gene expression was tissue-dependent and increased with increasing temperature in the gills and liver while showing an opposite pattern in the spleen. Studying a pair of sister species that occur across the Antarctic Polar Front can help us understand the particular pressures of intertidal lifestyles and the effect of temperature in combination with biological stressors on cell damage and repair capacity in a changing environment.


Asunto(s)
Apoptosis , Perciformes , Temperatura , Animales , Regiones Antárticas , Perciformes/inmunología , Perciformes/genética , Poli I-C/farmacología , Ubiquitina/genética , Ubiquitina/metabolismo , Lipopolisacáridos/farmacología , Regulación de la Expresión Génica , Branquias/metabolismo , Branquias/inmunología , Proteínas de Peces/genética , Proteínas de Peces/metabolismo , Bazo/inmunología , Bazo/metabolismo
17.
Int J Aging Hum Dev ; 99(1): 96-114, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38111265

RESUMEN

Telemedicine provided older adults the ability to safely seek care during the coronavirus disease (COVID-19) pandemic. This study aimed to evaluate the potential impact of acculturation factors in telemedicine uptake between ethnic groups. As part of the National Health and Aging Trends Study 2018 survey, 303 participants (≥65 years) were interviewed. We assessed the impact of acculturation on telemedicine readiness by race and ethnicity. Compared to the white non-Hispanic immigrant population, Hispanic and Asian/Pacific Islander (API) populations had significantly lower telemedicine readiness and uptake. Limited English proficiency or older age at the time of migration was associated with telemedicine unreadiness and uptake in the Hispanic and API populations. Our findings suggested that acculturation factors play a substantial role in telemedicine uptake among older adult immigrants in the United States. Therefore, acculturation factors should be considered when promoting and adopting telemedicine technologies in older adults.


Asunto(s)
Aculturación , COVID-19 , Telemedicina , Humanos , Telemedicina/estadística & datos numéricos , Anciano , Femenino , Masculino , COVID-19/etnología , Estados Unidos , Disparidades en Atención de Salud/etnología , Disparidades en Atención de Salud/estadística & datos numéricos , Anciano de 80 o más Años , Emigrantes e Inmigrantes/estadística & datos numéricos , Etnicidad/estadística & datos numéricos , SARS-CoV-2 , Aceptación de la Atención de Salud/etnología , Aceptación de la Atención de Salud/estadística & datos numéricos
18.
Med Oral Patol Oral Cir Bucal ; 29(2): e263-e272, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38288853

RESUMEN

BACKGROUND: Mandibular third molar (MTM) extraction is one of the most frequently performed surgeries in the oral cavity. Establishing the level of surgical difficulty pre-operatively is an essential step to ensure correct treatment planning. In Spain, MTM extraction - especially in cases presenting greater difficulty - is normally performed by doctors specializing in oral and maxillofacial surgery, or by dentists with postgraduate qualifications in oral surgery. The present work set out to analyze the extent to which perceptions of surgical difficulty of the said intervention vary in relation to professional training. MATERIAL AND METHODS: This cross-sectional, descriptive, observational study took the form of a survey. Using a visual analog scale (VAS), participants evaluated both the perceived difficulty of 30 cases of MTM extraction described by means of digital panoramic radiographs and the perceived difficulty deriving from a series of factors conditioning MTM extraction. The results underwent statistical analysis with SPSS Statistics 28.0 software. Non-parametric tests (Mann Whitney test for independent samples and the Kruskal-Wallis test) were applied. RESULTS: A total of 213 surveys were available for analysis. Both groups awarded the greatest importance to clinical experience, followed by anatomical and radiographic factors, root morphology obtaining the highest score among anatomical factors (9.01±1.42), while proximity of the MTM to the inferior alveolar nerve was regarded as the least important anatomical factor (8.11±2.54). Significant differences were only found for patient age, whereby maxillofacial surgeons awarded this factor more importance than dentists. CONCLUSIONS: The different training received by dentists specialized in oral surgery and maxillofacial surgeons did not influence either perceptions of surgical difficulty of MTM extraction, or opinions as to the factors influencing surgical difficulty.


Asunto(s)
Cirujanos Oromaxilofaciales , Cirugía Bucal , Humanos , Estudios Transversales , Tercer Molar/cirugía , Extracción Dental
19.
J Sports Sci ; 41(22): 2033-2044, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38341865

RESUMEN

We aim to evaluate the prevalence of reporting and the extent of statistical heterogeneity of systematic reviews with meta-analyses (SRMAs) of exercise training for hypertension and to provide practical recommendations for dealing with statistical heterogeneity. We systematically searched on four databases (from 2002 to September of 2023) for SRMAs comparing exercise interventions vs. a non-exercise control on blood pressure (BP) control in adults with hypertension. Fifty-nine SRMAs, with a median of 14 studies, were analysed. Cochran's Q (41%), I2 (24%), forest plots (44%), and particularly τ2 (54%) and prediction intervals (96.6%) frequently were not reported for the hypertension subgroup. The recalculated prediction intervals were discrepant (i.e., crossed the null effect) of significant 95% confidence intervals of most meta-analyses (systolic BP: 65%; diastolic BP: 92%). This suggests substantial heterogeneity across studies, which was often not acknowledged by authors' conclusions (78%). Consequently, downgrading the certainty of the available evidence may be justified alone due to heterogeneity across studies. Finally, we illustrate areas for improving I2 interpretation and provide practical recommendations on how to address statistical heterogeneity across all stages of a SRMA.


Asunto(s)
Hipertensión , Adulto , Humanos , Presión Sanguínea , Ejercicio Físico , Hipertensión/epidemiología , Revisiones Sistemáticas como Asunto , Metaanálisis como Asunto
20.
Int J Mol Sci ; 25(1)2023 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-38203699

RESUMEN

Bacteriophage endolysins are bacteriolytic enzymes that have been explored as potential weapons to fight antibiotic-resistant bacteria. Despite several studies support the application of endolysins as enzybiotics, detailed knowledge on cellular and enzymatic factors affecting their lytic activity is still missing. The bacterial membrane proton motive force (PMF) and certain cell wall glycopolymers of Gram-positive bacteria have been implicated in some tolerance to endolysins. Here, we studied how the anti-staphylococcal endolysin Lys11, a modular enzyme with two catalytic domains (peptidase and amidase) and a cell binding domain (CBD11), responded to changes in the chemical and/or electric gradients of the PMF (ΔpH and Δψ, respectively). We show that simultaneous dissipation of both gradients enhances endolysin binding to cells and lytic activity. The collapse of ΔpH is preponderant in the stimulation of Lys11 lytic action, while the dissipation of Δψ is mainly associated with higher endolysin binding. Interestingly, this binding depends on the amidase domain. The peptidase domain is responsible for most of the Lys11 bacteriolytic activity. Wall teichoic acids (WTAs) are confirmed as major determinants of endolysin tolerance, in part by severely hindering CBD11 binding activity. In conclusion, the PMF and WTA interfere differently with the endolysin functional domains, affecting both the binding and catalytic efficiencies.


Asunto(s)
Péptido Hidrolasas , Staphylococcus , Amidohidrolasas , Antibacterianos , Bacteriólisis
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