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1.
J Chem Theory Comput ; 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38723159

RESUMEN

Quantum computing is emerging as a new computational paradigm with the potential to transform several research fields including quantum chemistry. However, current hardware limitations (including limited coherence times, gate infidelities, and connectivity) hamper the implementation of most quantum algorithms and call for more noise-resilient solutions. We propose an explicitly correlated Ansatz based on the transcorrelated (TC) approach to target these major roadblocks directly. This method transfers, without any approximation, correlations from the wave function directly into the Hamiltonian, thus reducing the resources needed to achieve accurate results with noisy quantum devices. We show that the TC approach allows for shallower circuits and improves the convergence toward the complete basis set limit, providing energies within chemical accuracy to experiment with smaller basis sets and, thus, fewer qubits. We demonstrate our method by computing bond lengths, dissociation energies, and vibrational frequencies close to experimental results for the hydrogen dimer and lithium hydride using two and four qubits, respectively. To demonstrate our approach's current and near-term potential, we perform hardware experiments, where our results confirm that the TC method paves the way toward accurate quantum chemistry calculations already on today's quantum hardware.

2.
J Chem Phys ; 160(19)2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38747435

RESUMEN

We explore the application of an extrapolative method that yields very accurate total and relative energies from variational and diffusion quantum Monte Carlo (VMC and DMC) results. For a trial wave function consisting of a small configuration interaction (CI) wave function obtained from full CI quantum Monte Carlo and reoptimized in the presence of a Jastrow factor and an optional backflow transformation, we find that the VMC and DMC energies are smooth functions of the sum of the squared coefficients of the initial CI wave function and that quadratic extrapolations of the non-backflow VMC and backflow DMC energies intersect within uncertainty of the exact total energy. With adequate statistical treatment of quasi-random fluctuations, the extrapolate and intersect with polynomials of order two method is shown to yield results in agreement with benchmark-quality total and relative energies for the C2, N2, CO2, and H2O molecules, as well as for the C2 molecule in its first electronic singlet excited state, using only small CI expansion sizes.

3.
Angew Chem Int Ed Engl ; : e202404859, 2024 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-38634763

RESUMEN

The low-electron count, air-stable, platinum complexes [Pt(ItBu')(ItBu)][BArF] (C1) (ItBu=1,3-di-tert-butylimidazol-2-ylidene), [Pt(SiPh)3(ItBuiPr)2][BArF] (C2) (ItBuiPr = 1-tert-butyl-3-iso-propylimidazol-2-ylidene),  [Pt(SiPh)3(ItBuMe)2][BArF] (C3), [Pt(GePh3)(ItBuiPr)2][BArF] (C4), [Pt(GePh)3(ItBuMe)2][BArF] (C5) and [Pt(GeEt)3(ItBuMe)2][BArF] (C6)  (ItBuMe = 1-tert-butyl-3-methylimidazol-2-ylidene) are efficient catalysts (particularly the germyl derivatives) in both the silylative dehydrocoupling and hydrosilylation of electron rich alkenes derived from enamines.  The steric hindrance exerted by the NHC ligand plays an important role in the selectivity of the reaction. Thus, bulky ligands are selective towards the silylative dehydrocoupling process whereas less sterically hindered promote the selective hydrosilylation reaction. The latter is, in addition, regioselective towards the ß-carbon atom of both internal and terminal enamines, leading to ß-aminosilanes. Moreover, the syn stereochemistry of the amino and silyl groups implies an anti Si‒H bond addition across the double bond. All these facts point to a mechanistic picture that, according to experimental and computational studies, involves a non-classical hydrosilylation process through an outer-sphere mechanism in which a formal nucleophilic addition of the enamine to the silicon atom of a platinum σ-SiH complex is the key step. This is in sharp contrast with the classical Chalk-Harrod mechanism prevalent in platinum chemistry.

4.
Methods Mol Biol ; 2705: 351-358, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37668983

RESUMEN

Src-homology-2 (SH2) domains bind selectively to phosphotyrosine (pTyr) residues located in target binding proteins; therefore, they are key elements in pTyr-mediated signaling pathways. The binding of an SH2 domain to a pTyr acts as a docking mechanism that attracts proteins into signaling hubs, and in some cases, it can also regulate the catalytic activity of signaling enzymes such as protein kinases or protein phosphatases. Therefore, compounds that selectively bind SH2 domains can be potentially used to modulate the activity of such SH2 domain-containing enzymes. This chapter describes how to measure the regulation of protein tyrosine phosphatase activity through allosteric binding of peptides to SH2 domains, and uses human recombinant protein tyrosine phosphatase SHP2 (Src homology-2 domain-containing protein tyrosine phosphatase 2) purified from bacteria as a case example. The phosphatase activity against the artificial substrate DiFMUP (6, 8-Difluoro-4-Methylumbelliferyl Phosphate) is measured over time in the presence of a peptide that selectively binds and activates SHP2 at different concentrations to determine the half maximal effective concentration (EC50).


Asunto(s)
Fosfatos , Dominios Homologos src , Humanos , Fosfotirosina , Procesamiento Proteico-Postraduccional , Transducción de Señal
5.
Methods Mol Biol ; 2705: 359-369, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37668984

RESUMEN

Phosphotyrosine (pTyr)-containing amino acid sequences have regulatory effects on proteins that contain pTyr recognition motifs, such as Src Homology 2 (SH2) domains. Using pTyr-containing peptides as a bait for coprecipitation, by immobilization of the synthesized phosphopeptides to beads and incubation with cell lysates, enables to study the binding preference of the SH2 domain for the specific pTyr-sequence obtained from a pTyr-containing protein in a complex biological environment. Using phosphopeptides allows to not only assess the wild-type sequence, but also peptides that can contain modified sequences which carry a nonhydrolyzable pTyr or other modifications varying the binding strength and selectivity, for example, to create strong SH2 domain binders to inhibit their interaction with pTyr-containing proteins. This pulldown experiment can be used as an assay to evaluate the ability of a peptide to bind to the protein of interest in the cell lysate or investigate the selectivity of the peptide. Therefore, immobilizing phosphopeptides and using them as a pulldown tool has a wide range of applications.


Asunto(s)
Fosfopéptidos , Dominios Homologos src , Secuencia de Aminoácidos , Bioensayo , Fosfotirosina
6.
Angew Chem Int Ed Engl ; 62(45): e202310307, 2023 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-37705304

RESUMEN

Reactions of a dicopper(I) tert-butoxide complex with alkynes possessing boryl or silyl capping groups resulted in formation of unprecedented tetracopper(I) µ-acetylide/diyne complexes that were characterized by NMR and UV/Vis spectroscopy, mass spectrometry and single-crystal X-ray diffraction. These compounds possess an unusual µ4 -η1 :η1 :η1 :η1 coordination mode for the bridging organic fragment, enforced by the rigid and dinucleating nature of the ligand utilized. Thus, the central π system remains unperturbed and accessible for subsequent reactivity and modification. This has been corroborated by addition of a fifth copper atom, giving rise to a pentacopper acetylide complex. This work may provide a new approach by which metal-metal cooperativity can be exploited in the transformation of acetylide and diyne groups to a variety of substrates, or as a starting point for the controlled synthesis of copper(I) alkyne-containing clusters.

7.
Angew Chem Int Ed Engl ; 62(34): e202306315, 2023 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-37399341

RESUMEN

The synthesis and characterization of (tBu PBP)Ni(OAc) (5) by insertion of carbon dioxide into the Ni-C bond of (tBu PBP)NiMe (1) is presented. An unexpected CO2 cleavage process involving the formation of new B-O and Ni-CO bonds leads to the generation of a butterfly-structured tetra-nickel cluster (tBu PBOP)2 Ni4 (µ-CO)2 (6). Mechanistic investigation of this reaction indicates a reductive scission of CO2 by O-atom transfer to the boron atom via a cooperative nickel-boron mechanism. The CO2 activation reaction produces a three-coordinate (tBu P2 BO)Ni-acyl intermediate (A) that leads to a (tBu P2 BO)-NiI complex (B) via a likely radical pathway. The NiI species is trapped by treatment with the radical trap (2,2,6,6-tetramethylpiperidin-1-yl)oxyl (TEMPO) to give (tBu P2 BO)NiII (η2 -TEMPO) (7). Additionally, 13 C and 1 H NMR spectroscopy analysis using 13 C-enriched CO2 provides information about the species involved in the CO2 activation process.

8.
J Chem Phys ; 159(1)2023 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-37409706

RESUMEN

An efficient implementation for approximate inclusion of the three-body operator arising in transcorrelated methods via exclusion of explicit three-body components (xTC) is presented and tested against results in the "HEAT" benchmark set [Tajti et al., J. Chem. Phys. 121, 011599 (2004)]. Using relatively modest basis sets and computationally simple methods, total, atomization, and formation energies within near-chemical accuracy from HEAT results were obtained. The xTC ansatz reduces the nominal scaling of the three-body part of transcorrelation by two orders of magnitude to O(N5) and can readily be used with almost any quantum chemical correlation method.

9.
J Chem Phys ; 158(22)2023 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-37290083

RESUMEN

We investigate the optimization of flexible tailored real-space Jastrow factors for use in the transcorrelated (TC) method in combination with highly accurate quantum chemistry methods, such as initiator full configuration interaction quantum Monte Carlo (FCIQMC). Jastrow factors obtained by minimizing the variance of the TC reference energy are found to yield better, more consistent results than those obtained by minimizing the variational energy. We compute all-electron atomization energies for the challenging first-row molecules C2, CN, N2, and O2 and find that the TC method yields chemically accurate results using only the cc-pVTZ basis set, roughly matching the accuracy of non-TC calculations with the much larger cc-pV5Z basis set. We also investigate an approximation in which pure three-body excitations are neglected from the TC-FCIQMC dynamics, saving storage and computational costs, and show that it affects relative energies negligibly. Our results demonstrate that the combination of tailored real-space Jastrow factors with the multi-configurational TC-FCIQMC method provides a route to obtaining chemical accuracy using modest basis sets, obviating the need for basis-set extrapolation and composite techniques.


Asunto(s)
Electrones , Método de Montecarlo
10.
J Chem Phys ; 158(21)2023 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-37259997

RESUMEN

We demonstrate the accuracy of ground-state energies of the transcorrelated Hamiltonian, employing sophisticated Jastrow factors obtained from variational Monte Carlo, together with the coupled cluster and distinguishable cluster methods at the level of singles and doubles excitations. Our results show that already with the cc-pVTZ basis, the transcorrelated distinguishable cluster method gets close to the complete basis limit and near full configuration interaction quality values for relative energies of over thirty atoms and molecules. To gauge the performance in different correlation regimes, we also investigate the breaking of the nitrogen molecule with transcorrelated coupled cluster methods. Numerical evidence is presented to further justify an efficient way to incorporate the major effects coming from the three-body integrals without explicitly introducing them into the amplitude equations.

11.
J Chem Phys ; 158(17)2023 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-37144717

RESUMEN

TREXIO is an open-source file format and library developed for the storage and manipulation of data produced by quantum chemistry calculations. It is designed with the goal of providing a reliable and efficient method of storing and exchanging wave function parameters and matrix elements, making it an important tool for researchers in the field of quantum chemistry. In this work, we present an overview of the TREXIO file format and library. The library consists of a front-end implemented in the C programming language and two different back-ends: a text back-end and a binary back-end utilizing the hierarchical data format version 5 library, which enables fast read and write operations. It is compatible with a variety of platforms and has interfaces for Fortran, Python, and OCaml programming languages. In addition, a suite of tools have been developed to facilitate the use of the TREXIO format and library, including converters for popular quantum chemistry codes and utilities for validating and manipulating data stored in TREXIO files. The simplicity, versatility, and ease of use of TREXIO make it a valuable resource for researchers working with quantum chemistry data.

12.
Int. j. morphol ; 41(2): 477-481, abr. 2023. tab
Artículo en Español | LILACS | ID: biblio-1440335

RESUMEN

Describir la morfología del sistema de canales radiculares del primer molar maxilar en una población chilena mediante exámenes de tomografía computarizada Cone-Beam (CBCT). Se realizó un estudio observacional descriptivo en el cual se utilizaron los exámenes CBCT de pacientes que fueron atendidos en un Centro de Radiología Maxilofacial privado durante el período comprendido entre Enero y Diciembre del año 2018 en la ciudad de Temuco, Chile, los cuales fueron observados de manera independiente por dos investigadores previamente calibrados. Se observaron 199 exámenes CBCT. En la raíz mesiobucal,predominaron las morfologías tipo II, I y IV de Vertucci respectivamente, mientras que en la raíz distobucal y palatina predominó la morfología tipo I. El canal MB2 estuvo presente en el 62,3 % de los casos, con una prevalencia significativamente mayor en pacientes jóvenes. En la mayoría de los primeros molares maxilares de los habitantes de la ciudad de Temuco se observaron tres raíces separadas y la presencia de cuatro canales. Se determinó una alta frecuencia del canal MB2 en la raíz MB.


SUMMARY: The objective of this study was to describe the morphology of the root canal system of the maxillary first molar in a Chilean population through Cone-Beam computed tomography (CBCT) examinations. A descriptive observational study was carried out in which the CBCT examinations of patients who were treated in a private maxillofacial radiology center during the period between January and December 2018 in Temuco, Chile, were used which were observed independently by two previously calibrated researchers. In this analysis 199 CBCT exams were observed. In the mesiobuccal root, Type II, I and IV morphologies predominated respectively, while in the distobuccal and palatal root, Type I morphology predominated. The MB2 canal was present in 62.3 % of cases, with a higher prevalence in young patients. Three separate roots and the presence of four canals were observed in most of the maxillary first molars of the patients in Temuco. A high frequency of the MB2 canal was determined in the root MB.


Asunto(s)
Humanos , Masculino , Femenino , Niño , Adolescente , Adulto , Persona de Mediana Edad , Anciano , Adulto Joven , Cavidad Pulpar/diagnóstico por imagen , Tomografía Computarizada de Haz Cónico , Diente Molar/diagnóstico por imagen , Chile , Distribución por Edad , Cavidad Pulpar/anatomía & histología , Maxilar , Diente Molar/anatomía & histología
13.
J Chem Theory Comput ; 19(6): 1734-1743, 2023 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-36912635

RESUMEN

We present the theory of a density matrix renormalization group (DMRG) algorithm which can solve for both the ground and excited states of non-Hermitian transcorrelated Hamiltonians and show applications in molecular systems. Transcorrelation (TC) accelerates the basis set convergence rate by including known physics (such as, but not limited to, the electron-electron cusp) in the Jastrow factor used for the similarity transformation. It also improves the accuracy of approximate methods such as coupled cluster singles and doubles (CCSD) as shown by recent studies. However, the non-Hermiticity of the TC Hamiltonians poses challenges for variational methods like DMRG. Imaginary-time evolution on the matrix product state (MPS) in the DMRG framework has been proposed to circumvent this problem, but this is currently limited to treating the ground state and has lower efficiency than the time-independent DMRG (TI-DMRG) due to the need to eliminate Trotter errors. In this work, we show that with minimal changes to the existing TI-DMRG algorithm, namely, replacing the original Davidson solver with the general Davidson solver to solve the non-Hermitian effective Hamiltonians at each site for a few low-lying right eigenstates, and following the rest of the original DMRG recipe, one can find the ground and excited states with improved efficiency compared to the original DMRG when extrapolating to the infinite bond dimension limit in the same basis set. An accelerated basis set convergence rate is also observed, as expected, within the TC framework.

14.
Acta bioquím. clín. latinoam ; 57(1): 126-130, mar. 2023.
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1513535

RESUMEN

Resumen La enfermedad renal crónica (ERC) es de alta prevalencia en América Latina y en todo el mundo. Se estima que entre 10 y 20% de la población adulta es portadora de ERC y su prevalencia va en aumento. La ERC progresa en forma silenciosa. Su diagnóstico temprano y oportuno permite iniciar un tratamiento efectivo, en la mayoría de los casos, para detener la enfermedad. Desde hace mucho tiempo, el análisis de la creatininemia es la principal prueba utilizada para valorar la función renal, pero su confiabilidad es limitada. De acuerdo con las recomendaciones de las GUIAS KDOQI del año 2002 la tasa de filtración glomerular estimada (TFGe) obtenida a través de fórmulas, se estableció como una de las herramientas principales para detectar la enfermedad renal de manera precoz, ya que alerta de forma precisa al médico y al equipo de salud sobre el nivel de función renal del paciente. La detección de una TFGe disminuida (menor de 60 mL/min/1,73 m2) es clínicamente relevante, ya que permite establecer el diagnóstico de enfermedad renal en adultos. En el año 2022, en una encuesta realizada por SLANH y COLABIOCLI dirigida a los laboratorios de análisis clínicos de América Latina (n: 237), el 49% de los mismos no informaban la TFGe rutinariamente. En base a esta realidad SLANH y COLABIOCLI elaboraron estas recomendaciones de consenso en referencia al uso de la TFGe.


Abstract Chronic kidney disease (CKD) has a high prevalence worldwide and in Latin America (10 to 20% of the adult population) and is increasing. CKD progresses silently. Opportune diagnosis and treatment are effective in most cases to improve outcomes. Serum creatinine was the main test to assess kidney function, but its reliability is limited. Through the KDOQI Guidelines 2002, the estimated glomerular filtration rate (eGFR) obtained from equations was established as one of the main tools for the early detection of kidney disease in clinical practice. The detection of a decreased eGFR (less than 60 mL/min/1.73 m2) is clinically relevant. This cut-off level establishes the diagnosis of kidney disease in adults. In 2022 SLANH and COLABIOCLI conducted a survey among the clinical laboratories from Latin America. The survey included 237 laboratories, 49% of which did not routinely report the eGFR. Based on this situation, SLANH and COLABIOCLI have elaborated the following consensus recommendations regarding the use of eGFR.


Resumo A doença renal crônica (DRC) é altamente prevalente na América Latina e em todo o mundo. Estima-se que entre 10 e 20% da população adulta seja portadora de DRC e sua prevalência esteja aumentando. A DRC progride silenciosamente. Seu diagnóstico precoce e oportuno permite iniciar um tratamento eficaz, na maioria dos casos, para estancar a doença. Faz muito tempo, a análise da creatinina tem sido o principal teste usado para avaliar a função renal mas sua confiabilidade é limitada. De acordo com as recomendações dos GUIAS KDOQI do ano de 2002, a estimativa da taxa de filtração glomerular (eGFR), obtida por meio de fórmulas, consolidou-se como uma das principais ferramentas para a detecção precoce da doença renal, visto que alerta com precisão ao médico e ao equipe de saúde sobre o nível de função renal do paciente. A detecção de uma eGFR diminuída (inferior a 60 mL/min/1,73 m2) é clinicamente relevante, pois permite estabelecer o diagnóstico de doença renal em adultos. No ano de 2022, em pesquisa realizada pela SLANH e COLABIOCLI dirigida a laboratórios de análises clínicas da América Latina (n: 237), 49% deles não relataram rotineiramente eGFR. Com base nessa realidade, SLANH e COLABIOCLI prepararam essas recomendações de consenso sobre o uso de eGFR.

15.
J Am Chem Soc ; 145(1): 179-193, 2023 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-36542802

RESUMEN

We report the dimerization and oligomerization of ethylene using bis(phosphino)boryl supported Ni(II) complexes as catalyst precursors. By using alkylaluminum(III) compounds or other Lewis acid additives, Ni(II) complexes of the type (RPBP)NiBr (R = tBu or Ph) show activity for the production of butenes and higher olefins. Optimized turnover frequencies of 640 molethylene·molNi-1·s-1 for the formation of butenes with 41(1)% selectivity for 1-butene using (PhPBP)NiBr, and 68 molethylene·molNi-1·s-1 for butenes production with 87.2(3)% selectivity for 1-butene using (tBuPBP)NiBr, have been demonstrated. With methylaluminoxane as a co-catalyst and (tBuPBP)NiBr as the precatalyst, ethylene oligomerization to form C4 through C20 products was achieved, while the use of (PhPBP)NiBr as the pre-catalyst retained selectivity for C4 products. Our studies suggest that the ethylene dimerization is not initiated by Ni hydride or alkyl intermediates. Rather, our studies point to a mechanism that involves a cooperative B/Ni activation of ethylene to form a key 6-membered borametallacycle intermediate. Thus, a cooperative activation of ethylene by the Ni-B unit of the (RPBP)Ni catalysts is proposed as a key element of the Ni catalysis.

16.
Acta Anaesthesiol Scand ; 67(2): 185-194, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36268561

RESUMEN

BACKGROUND: Gravity-dependent positioning therapy is an established concept in the treatment of severe acute respiratory distress syndrome and improves oxygenation in spontaneously breathing patients with hypoxemic acute respiratory failure. In patients with coronavirus disease 2019, this therapy seems to be less effective. Electrical impedance tomography as a point-of-care functional imaging modality for visualizing regional ventilation can possibly help identify patients who might benefit from positioning therapy and guide those maneuvers in real-time. Therefore, in this prospective observational study, we aimed to discover typical patterns in response to positioning maneuvers. METHODS: Distribution of ventilation in 10 healthy volunteers and in 12 patients with hypoxemic respiratory failure due to coronavirus disease 2019 was measured in supine, left, and right lateral positions using electrical impedance tomography. RESULTS: In this study, patients with coronavirus disease 2019 showed a variety of ventilation patterns, which were not predictable, whereas all but one healthy volunteer showed a typical and expected gravity-dependent distribution of ventilation with the body positions. CONCLUSION: Distribution of ventilation and response to lateral positioning is variable and thus unpredictable in spontaneously breathing patients with coronavirus disease 2019. Electrical impedance tomography might add useful information on the immediate reaction to postural maneuvers and should be elucidated further in clinical studies. Therefore, we suggest a customized individualized positioning therapy guided by electrical impedance tomography.


Asunto(s)
COVID-19 , Insuficiencia Respiratoria , Humanos , Impedancia Eléctrica , Tomografía/métodos , COVID-19/terapia , Respiración , Tomografía Computarizada por Rayos X
17.
Inorg Chem ; 61(51): 20848-20859, 2022 Dec 26.
Artículo en Inglés | MEDLINE | ID: mdl-36322561

RESUMEN

The low electron count Pt(II) complexes [Pt(NHC')(NHC)][BArF] (where NHC is a N-heterocyclic carbene ligand and NHC' its metalated form) react with tertiary hydrogermanes HGeR3 at room temperature to generate the 14-electron platinum(II) germyl derivatives [Pt(GeR3)(NHC)2][BArF]. Low-temperature NMR studies allowed us to detect and characterize spectroscopically some of the σ-GeH intermediates [Pt(η2-HGeR3)(NHC')(NHC)][BArF] that evolve into the platinum-germyl species. One of these compounds has been characterized by X-ray diffraction studies, and the interaction of the H-Ge bond with the platinum center has been analyzed in detail by computational methods, which suggest that the main contribution is the donation of the H-Ge to a σ*(Pt-C) orbital, but backdonation from the platinum to the σ*(Ge-H) orbital is significant. Primary and secondary hydrogermanes also produce the corresponding platinum-germyl complexes, a result that contrasts with the reactivity observed with primary silanes, in which carbon-silicon bond-forming reactions have been reported. According to density functional theory calculations, the formation of Pt-Ge/C-H bonds is both kinetically and thermodynamically preferred over the competitive reaction pathway leading to Pt-H/C-Ge bonds.

18.
PLoS One ; 17(10): e0266617, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36240220

RESUMEN

INTRODUCTION: The Renal Healthcare Program Uruguay (NRHP-UY) is a national, multidisciplinary program that provides care to chronic kidney disease (CKD) patients. In this study, we report the global results of CKD patient outcomes and a comparison between those treated at the NRHP-UY Units, with those patients who were initially included in the program but did not adhere to follow up. METHODS: A cohort of not-on dialysis CKD patients included prospectively in the NRHP-UY between October 1st 2004 and September 30th 2017 was followed-up until September 30th 2019. Two groups were compared: a) Nephrocare Group: Patients who had at least one clinic visit during the first year on NRHP-UY (n = 11174) and b) Non-adherent Group: Patients who were informed and accepted to be included but had no subsequent data registered after admission (n = 3485). The study was approved by the Ethics Committee and all patients signed an informed consent. Outcomes were studied with Logistic and Cox´s regression analysis, Fine and Gray competitive risk and propensity-score matching tests. RESULTS: 14659 patients were analyzed, median age 70 (60-77) years, 56.9% male. The Nephrocare Group showed improved achievement of therapeutic goals, ESKD was more frequent (HR 2.081, CI 95%1.722-2.514) as planned kidney replacement therapy (KRT) start (OR 2.494, CI95% 1.591-3.910), but mortality and the combined event (death and ESKD) were less frequent (HR 0.671, CI95% 0.628-0.717 and 0.777, CI95% 0.731-0.827) (p = 0.000) compared to the Non-adherent group. Results were similar in the propensity-matched group: ESKD (HR 2.041, CI95% 1.643-2.534); planned kidney replacement therapy (KRT) start (OR 2.191, CI95% 1.322-3.631) death (HR 0.692, CI95% 0.637-0.753); combined event (HR 0.801, CI95% 0.742-0.865) (p = 0.000). CONCLUSION: Multidisciplinary care within the NRHP-UY is associated with timely initiation of KRT and lower mortality in single outcomes, combined analysis, and propensity-matched analysis.


Asunto(s)
Fallo Renal Crónico , Insuficiencia Renal Crónica , Anciano , Estudios de Cohortes , Progresión de la Enfermedad , Femenino , Humanos , Fallo Renal Crónico/complicaciones , Fallo Renal Crónico/terapia , Masculino , Estudios Prospectivos , Insuficiencia Renal Crónica/complicaciones , Terapia de Reemplazo Renal
19.
J Opt Soc Am A Opt Image Sci Vis ; 39(9): 1558-1568, 2022 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-36215622

RESUMEN

The nonparaxial interference and diffraction by a planar array of emitters have been recently described in terms of the light energy confinement in Lorentzian wells, which are spatially structured by the geometric potential, activated in turn by the two-point correlation prepared at the array plane. Nevertheless, the use of nonplanar arrays of light emitters is of increasing interest in optical technology. Therefore, we extend the confinement model to include spatially structured Lorentzian wells by geometric potentials associated with nonplanar distributions of points. Such geometric potentials are activated by two-point correlations with 3D supports prepared at the nonplanar array. The theoretical analysis is supported and illustrated by numerical simulations.

20.
Clin Cancer Res ; 28(21): 4771-4781, 2022 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-36074126

RESUMEN

PURPOSE: Early intervention in smoldering multiple myeloma (SMM) requires optimal risk stratification to avoid under- and overtreatment. We hypothesized that replacing bone marrow (BM) plasma cells (PC) for circulating tumor cells (CTC), and adding immune biomarkers in peripheral blood (PB) for the identification of patients at risk of progression due to lost immune surveillance, could improve the International Myeloma Working Group 20/2/20 model. EXPERIMENTAL DESIGN: We report the outcomes of 150 patients with SMM enrolled in the iMMunocell study, in which serial assessment of tumor and immune cells in PB was performed every 6 months for a period of 3 years since enrollment. RESULTS: Patients with >0.015% versus ≤0.015% CTCs at baseline had a median time-to-progression of 17 months versus not reached (HR, 4.9; P < 0.001). Presence of >20% BM PCs had no prognostic value in a multivariate analysis that included serum free light-chain ratio >20, >2 g/dL M-protein, and >0.015% CTCs. The 20/2/20 and 20/2/0.015 models yielded similar risk stratification (C-index of 0.76 and 0.78). The combination of the 20/2/0.015 model with an immune risk score based on the percentages of SLAN+ and SLAN- nonclassical monocytes, CD69+HLADR+ cytotoxic NK cells, and CD4+CXCR3+ stem central memory T cells, allowed patient' stratification into low, intermediate-low, intermediate-high, and high-risk disease with 0%, 20%, 39%, and 73% rates of progression at 2 years. CONCLUSIONS: This study showed that CTCs outperform BM PCs for assessing tumor burden. Additional analysis in larger series are needed to define a consensus cutoff of CTCs for minimally invasive stratification of SMM.


Asunto(s)
Mieloma Múltiple , Mieloma Múltiple Quiescente , Humanos , Progresión de la Enfermedad , Pronóstico , Cadenas Ligeras de Inmunoglobulina , Medición de Riesgo , Mieloma Múltiple/diagnóstico , Mieloma Múltiple/terapia
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