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1.
Phys Chem Chem Phys ; 25(7): 5885, 2023 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-36723247

RESUMEN

Correction for 'Structure effects of Pt15 clusters for the oxygen reduction reaction: first-principles calculations' by Peter L. Rodríguez-Kessler et al., Phys. Chem. Chem. Phys., 2023, https://doi.org/10.1039/d2cp05188e.

2.
Int Urol Nephrol ; 55(7): 1799-1809, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36753015

RESUMEN

PURPOSE: We evaluated the renal arterial resistive index (RRI), urine monocyte chemotactic protein 1 (uMCP-1), and urine neutrophil gelatinase-associated lipocalin (uNGAL) to predict acute kidney injury (AKI) in critically ill cancer patients. METHODS: In this prospective study, we included patients without AKI. We compared the area under the curve (AUC) of RRI, uMCP-1, and uNGAL to predict any stage of AKI and stage-3 AKI with the DeLong method, and we established cutoff points with the Youden index. RESULTS: We included 64 patients, and 43 (67.2%) developed AKI. The AUC to predict AKI were: 0.714 (95% CI 0.587-0.820) for the RRI, 0.656 (95% CI 0.526-0.770) for uMCP-1, and 0.677 (95% CI 0.549-0.789) for uNGAL. The AUC to predict stage-3 AKI were: 0.740 (95% CI 0.615-0.842) for the RRI, 0.757 (95% CI 0.633-0.855) for uMCP-1, and 0.817 (95% CI 0.701-0.903) for uNGAL, without statistical differences among them. For stage 3 AKI prediction, the sensitivity and specificity were: 56.3% and 87.5% for a RRI > 0.705; 70% and 79.2% for an uMCP-1 > 2169 ng/mL; and 87.5% and 70.8% for a uNGAL > 200 ng/mL. The RRI was significantly correlated to age (r = 0.280), estimated glomerular filtration rate (r = - 0.259), mean arterial pressure (r = - 0.357), and serum lactate (r = 0.276). CONCLUSION: The RRI, uMCP-1, and uNGAL have a similar ability to predict AKI. The RRI is more specific, while urine biomarkers are more sensitive to predict stage 3 AKI. The RRI correlates with hemodynamic variables. The novel uMCP-1 could be a useful biomarker that needs to be extensively studied.


Asunto(s)
Lesión Renal Aguda , Neoplasias , Humanos , Lesión Renal Aguda/diagnóstico , Biomarcadores , Quimiocina CCL2 , Enfermedad Crítica , Lipocalina 2 , Estudios Prospectivos
3.
Phys Chem Chem Phys ; 25(6): 4764-4772, 2023 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-36692089

RESUMEN

In the present work, the lowest energy structures and electronic properties of Pt15 clusters are investigated using molecular dynamics simulations. The results showed that the most stable configuration is a capped pyramidal structure, which is 0.8 kal mol-1 lower in energy than a layered structure previously reported [V. Kumar and Y. Kawazoe, Evolution of Atomic and Electronic Structure of Pt Clusters: Planar, Layered, Pyramidal, Cage, Cubic, and Octahedral Growth, Phys. Rev. B: Condens. Matter Mater. Phys., 2008, 77, 205418.]. The result is further confirmed by using both the PW91/cc-pVDZ-PP and PBE/PW approaches including the other representative isomers for Pt15. Due to the interesting structure arrangements found, we have investigated the catalytic activities for the oxygen reduction reaction. We found that the most stable Pt15 clusters are plausible catalyts for the ORR according to their interaction with oxygen species, which is consistent with experiments of Pt clusters with atomicity below 20. The results of the structure, electronic, adsorption and vibrational properties of the clusters are provided.

4.
Front Chem ; 10: 841964, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35300385

RESUMEN

The relative populations of Cu38 isomers depend to a great extent on the temperature. Density functional theory and nanothermodynamics can be combined to compute the geometrical optimization of isomers and their spectroscopic properties in an approximate manner. In this article, we investigate entropy-driven isomer distributions of Cu38 clusters and the effect of temperature on their IR spectra. An extensive, systematic global search is performed on the potential and free energy surfaces of Cu38 using a two-stage strategy to identify the lowest-energy structure and its low-energy neighbors. The effects of temperature on the populations and IR spectra are considered via Boltzmann factors. The computed IR spectrum of each isomer is multiplied by its corresponding Boltzmann weight at finite temperature. Then, they are summed together to produce a final temperature-dependent, Boltzmann-weighted spectrum. Our results show that the disordered structure dominates at high temperatures and the overall Boltzmann-weighted spectrum is composed of a mixture of spectra from several individual isomers.

5.
Phys Chem Chem Phys ; 24(13): 7856-7861, 2022 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-35302144

RESUMEN

In this work, we have performed a computational study on the structure and electronic properties for Be-doped Ptn (n = 1-12) clusters in the framework of density functional theory (DFT). The most stable structures of the clusters are obtained by a structure search procedure based in simulated annealing. The results show that the PtnBe clusters adopt compact structure motifs with Be situated at the edge sites while only in Pt11Be the Be atom occupies the center site. The energetic parameters showed that Pt5Be, Pt7Be and Pt10Be are the most stable ones. The PtnBe clusters with (n = 5-7) have similar vertical ionization potential (vIP) and vertical electron affinity (vEA) parameters compared to the unary Pt clusters, while Pt9Be and Pt11Be have the higher vEA values. In particular, the d-band center is slightly higher for the doped clusters, suggesting an enhanced reactivity. The σ-holes are found more remarkable for the doped clusters, which are situated in the Be dopant and low coordinated Pt sites. The data on the infrared spectra of the clusters is also provided and showed a significant blue shift due to the vibrational modes of the Be atom. These results are useful for understanding the fundamental properties of Be-doped Ptn clusters in the subnanometer region.

6.
J Palliat Care ; 36(3): 175-180, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33940980

RESUMEN

OBJECTIVE: To determine the outcomes of hospitalized cancer patients requiring intensive care unit (ICU) intervention and receiving palliative care. MATERIALS AND METHODS: An observational retrospective study was completed at a single academic critical care unit in Mexico City. All hospitalized cancer patients who were evaluated by the intensive care team to assess need for ICU were included between January and December 2018. RESULTS: During the study period, the ICU group made 408 assessments of critically ill cancer patients in noncritical hospitalized areas. In total, 24.2% (99/408) of the patients in this population were consulted by the palliative care team. Of the patients evaluated, 46.5% (190/408) had advanced stage, but only 28.4% were receiving care by the palliative care team. The only risk factor for hospital mortality in the multivariate analysis was the quick Sequential Organ Failure Assessment (qSOFA) score at the time of the consultation by the ICU group (HR = 2.10, 95% CI = 1.34-3.29, p = 0.001). The median time between palliative care consultation and death was 3 days (IQR = 2-22). A total of 63% (37/58) of patients who were discharged from the hospital died during follow-up. The median follow-up time was 55 days (95% CI = 26.9-83.0). The overall mortality rate for the entire group during hospitalization and after hospital discharge was 80.8% (80/99). CONCLUSION: Fewer than 3 out of 10 hospitalized cancer patients requiring admission to the ICU were evaluated by the palliative care team despite having incurable cancer. The qSOFA score of patients at the time of the ICU consultation was the only risk factor for mortality during hospitalization. Future research efforts in Mexico should focus on earlier integration of palliation care with usual oncology care in incurable cancer patients.


Asunto(s)
Enfermedad Crítica , Neoplasias , Cuidados Paliativos , Humanos , México , Neoplasias/terapia , Estudios Retrospectivos
7.
Phys Chem Chem Phys ; 23(22): 12904-12906, 2021 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-34042926

RESUMEN

Recently, P. V. Nhat et al., have discussed and commented on our article (DOI: 10.1039/D0CP04018E) for the case of the most stable structure of Ag15. They have found a new most stable structure (labeled as 15-1) in comparison to the putative global minimum reported by us, which is a four layered 1-4-6-4 stacking structure with a C2v point group (15-2). In this reply, we have performed a larger structure search which allowed us to confirm the results of Nhat et al. The results show the existence of multiple isoenergetic isomers with similar structure motifs for the Ag15 system, increasing the problem complexity to locate the global minimum. The results in regard to the structure and electronic properties of the new lowest energy structure are discussed.

9.
Int J Cancer ; 148(10): 2571-2578, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33368249

RESUMEN

Cervical cancer remains a leading cause of cancer death for women in low- and middle-income countries. The goal of our study was to evaluate screening and triage strategies, including high-resolution microendoscopy (HRME), to detect cervical abnormalities concerning for precancer at the point of care. Women (n = 1824) were enrolled at the Instituto de Cáncer de El Salvador. All underwent screening by both human papillomavirus (HPV) testing using careHPV and visual inspection with acetic acid (VIA). Screen-positives, along with 10% of screen-negatives, were invited to return for a follow-up examination that included triage with VIA, colposcopy and HRME imaging. Biopsies were taken of any abnormalities identified. If no abnormalities were identified, then the worst scoring site by HRME was biopsied. The sensitivities of HPV testing and VIA to screen for cervical intraepithelial neoplasia Grade 2 or more severe diagnoses (CIN2+) were 82.1% and 75% (P = .77), while the specificities were 90.4% and 80.9% (P < .001), respectively. The sensitivities of VIA, colposcopy and HRME as triage tests for CIN2+ were 82.1%, 82.1% and 71.4%, respectively (P ≥ .38). HRME had a significantly higher specificity (66.7%) than VIA (51.9%) (P < .001) and colposcopy (53.3%) (P < .001). When evaluating different theoretical screening and triage strategies, screening with HPV testing followed by triage with HRME would result in more women receiving appropriate care (97%) compared to screening with VIA (75%) or HPV alone (90%). Our findings demonstrate that screening with HPV is superior to VIA, and that triage with HRME imaging increases the specificity of detecting CIN2+ at the point of care in a low-resource setting.

10.
Phys Chem Chem Phys ; 22(46): 27255-27262, 2020 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-33227109

RESUMEN

In the present work, the lowest energy structures and electronic properties of Agn clusters up to n = 16 are investigated using a successive growth algorithm coupled with density functional theory calculations (DFT). In the literature, a number of putative global minimum structures for silver clusters have been reported by using different approaches, but a comparative study for n = 15-16 has not been undertaken so far. Here, we perform a comparative study using the PW91/cc-pVDZ-PP level to more precisely determine the optimal configuration. For Ag15, the most stable configuration is a four layered 1-4-6-4 stacking structure with C2v symmetry. For Ag16 a new most stable form is found with a 1-4-2-5-1-3 stacking structure in the singlet state, slightly more stable than the putative global minimum reported. By means of the electrostatic potential, the new putative global minimum has been found to be more reactive, and the active sites of the clusters were identified and confirmed with the interaction energy. The electronic and vibrational properties are found to be in good agreement with the available experimental data. Theoretical data on the infrared spectra of the clusters is also provided.

11.
Cancer ; 71(8): 2472-6, 1993 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-8453570

RESUMEN

BACKGROUND: Laryngeal cancer is the primary cause of death among patients with head and neck cancer in Argentina. Different prognostic factors have been incidentally dealt with in a number of articles, but there are few studies of prognostic variables, such as age, tobacco, and alcohol, using multifactorial analysis. METHODS: Between 1969-1987, 296 male patients with epidermoid carcinoma of the larynx treated at the Institute of Oncology "Angel H. Roffo" were studied regarding prognostic factors of survival. The effect of age, tobacco, alcohol, histologic grade, extent of primary tumor, and cord mobility on survival were assessed by means of the Cox proportional-hazards model. RESULTS: The univariate analysis showed that primary tumor extent, nodal involvement, stage, alcohol intake, previous tracheostomy, and cord mobility were statistically significant predictors of survival. Multivariate analysis disclosed only nodal involvement, alcohol intake, and cord mobility as statistically significant variables in regard to survivorship. With these variables, a hazard index was calculated for each patient, and four risk groups were formed. Five-year survival rates were as follows: Group A, 79%; B, 69%; C, 47%; and D, 14% (A versus C, P < 0.005; A versus D, P < 0.005). CONCLUSIONS: This study confirmed the prognostic impact of nodal involvement and also showed the importance of cord fixation and alcohol drinking as predictors of survival.


Asunto(s)
Consumo de Bebidas Alcohólicas/efectos adversos , Neoplasias Laríngeas/mortalidad , Fumar/efectos adversos , Anciano , Argentina/epidemiología , Humanos , Neoplasias Laríngeas/etiología , Neoplasias Laríngeas/patología , Metástasis Linfática , Masculino , Persona de Mediana Edad , Análisis Multivariante , Pronóstico , Análisis de Regresión , Estudios Retrospectivos , Pliegues Vocales/fisiopatología
12.
Revista de la Asociación Odontológica Argentina;94(3): 253-259,
en Español | URUGUAIODONTO | ID: odn-20565

Asunto(s)
Leiomiosarcoma , Maxilar
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