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1.
J Alzheimers Dis ; 98(2): 601-618, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38427484

RESUMEN

Background: Microglial dysfunction plays a causative role in Alzheimer's disease (AD) pathogenesis. Here we focus on a germline insertion/deletion variant mapping SIRPß1, a surface receptor that triggers amyloid-ß(Aß) phagocytosis via TYROBP. Objective: To analyze the impact of this copy-number variant in SIRPß1 expression and how it affects AD molecular etiology. Methods: Copy-number variant proxy rs2209313 was evaluated in GERALD and GR@ACE longitudinal series. Hippocampal specimens of genotyped AD patients were also examined. SIRPß1 isoform-specific phagocytosis assays were performed in HEK393T cells. Results: The insertion alters the SIRPß1 protein isoform landscape compromising its ability to bind oligomeric Aß and its affinity for TYROBP. SIRPß1 Dup/Dup patients with mild cognitive impairment show an increased cerebrospinal fluid t-Tau/Aß ratio (p = 0.018) and a higher risk to develop AD (OR = 1.678, p = 0.018). MRIs showed that Dup/Dup patients exhibited a worse initial response to AD. At the moment of diagnosis, all patients showed equivalent Mini-Mental State Examination scores. However, AD patients with the duplication had less hippocampal degeneration (p < 0.001) and fewer white matter hyperintensities. In contrast, longitudinal studies indicate that patients bearing the duplication allele show a slower cognitive decline (p = 0.013). Transcriptional analysis also shows that the SIRPß1 duplication allele correlates with higher TREM2 expression and an increased microglial activation. Conclusions: The SIRPß1 internal duplication has opposite effects over MCI-to-Dementia conversion risk and AD progression, affecting microglial response to Aß. Given the pharmacological approaches focused on the TREM2-TYROBP axis, we believe that SIRPß1 structural variant might be considered as a potential modulator of this causative pathway.


Asunto(s)
Enfermedad de Alzheimer , Disfunción Cognitiva , Receptores de Superficie Celular , Humanos , Enfermedad de Alzheimer/diagnóstico por imagen , Enfermedad de Alzheimer/genética , Péptidos beta-Amiloides/metabolismo , Disfunción Cognitiva/diagnóstico por imagen , Disfunción Cognitiva/genética , Disfunción Cognitiva/metabolismo , Microglía/metabolismo , Fagocitosis , Receptores de Superficie Celular/metabolismo
2.
Molecules ; 27(9)2022 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-35566169

RESUMEN

Benzenesulfonamides are a class of molecules of extreme interest in the biochemical field because many of them are active against a variety of diseases. In this work, the pharmacophoric group benzensulfonamide, its derivatives para-toluensulfonamide and ortho-toluensulfonamide, and the bioactive molecule sulfanilamide, were investigated using rotational spectroscopy to determine their conformations and the influence of different substituents on their structures. For all species, the hyperfine structure due to the 14N atom was analyzed, and this provided crucial information for the unambiguous identification of the observed conformation of all molecules. In addition, for ortho-toluensulfonamide, the vibration-rotation hyperfine structure related to the methyl torsion was analyzed, and the methyl group rotation barrier was determined. For benzensulfonamide, partial rS and r0 structures were established from the experimental rotational constants of the parent and two deuterated isotopic species. In all compounds except ortho-toluensulfonamide, the amino group of the sulfonamide group lies perpendicular to the benzene plane with the aminic hydrogens eclipsing the oxygen atoms. In ortho-toluensulfonamide, where weak attractive interactions occur between the nitrogen lone pair and the methyl hydrogen atoms, the amino group lies in a gauche orientation, retaining the eclipsed configuration with respect to the SO2 frame. A comparison of the geometrical arrangements found in the PDB database allowed us to understand that the bioactive conformations are different from those found in isolated conditions. The conformations within the receptor are reached with an energy cost, which is balanced by the interactions established in the receptor.


Asunto(s)
Benceno , Sulfonamidas , Conformación Molecular , Rotación , Análisis Espectral
3.
Spectrochim Acta A Mol Biomol Spectrosc ; 270: 120844, 2022 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-35007907

RESUMEN

Dinitriles with a saturated hydrocarbon skeleton and a -C≡N group at each end can have large electric dipole moments. Their formation can be related to highly reactive radicals such as CH2CN, C2N, or CN. Thus, these saturated dinitriles are potential candidates to be observed in the interstellar medium. In this work, two members of this family, hexanedinitrile and heptanedinitrile, have been investigated through their rotational spectra. The jet-cooled broadband chirped-pulse Fourier transform microwave spectra of both molecules were measured in the 2-8 GHz frequency region. Three and six conformers of hexanedinitrile and heptanedinitrile, respectively, were detected and assigned based on the rotational and quadrupole coupling constants.


Asunto(s)
Microondas , Análisis de Fourier , Conformación Molecular , Nitrilos , Análisis Espectral
4.
Spectrochim Acta A Mol Biomol Spectrosc ; 270: 120846, 2022 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-35033807

RESUMEN

Methyl vinyl ketone is one of the major oxidation products of isoprene, and therefore, an important precursor of secondary organic aerosol. Understanding its interactions with water is relevant to gain insight into aerosol formation and improve the predictive power of atmospheric chemistry models. The molecular complex formed between methyl vinyl ketone and water has been generated in a supersonic jet and characterized using high-resolution microwave spectroscopy in combination with quantum chemistry calculations. In this study, we show that methyl vinyl ketone interacts with water forming four 1:1 isomers connected by O - H···O and C - H···O hydrogen bond interactions. Water has been found to preferentially bind to the antiperiplanar conformation of methyl vinyl ketone. Evidence of a large amplitude motion arising from the methyl internal rotation has been found in the rotational spectra of the dimer. The threefold methyl internal rotation barrier heights have been further determined and discussed for all the species.


Asunto(s)
Butanonas , Agua , Enlace de Hidrógeno , Conformación Molecular
5.
J Phys Chem Lett ; 12(51): 12419-12425, 2021 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-34939809

RESUMEN

The hydration of ketones is known to occur in condensed phases, but it is not considered to be favorable in the gas phase due to restricted water content. We report the first evidence of geminal diol formation upon ketone hydration in the gas phase, obtained through the investigation of the interactions of cyclooctanone with water using broadband rotational spectroscopy. Oxygen-atom exchange between water and cyclooctanone was observed for two isomers of cyclooctanone-H2O and two isomers of cyclooctanone-(H2O)2. All complexes were unambiguously identified from the analysis of the rotational spectrum of the parent species and all their 13C and 18O isotopologues, and their heavy-atom substitution and effective structures were determined as well as their binding interactions. The production of gem-diols from gas-phase hydration of ketones has implications for atmospheric chemistry and opens a new channel for secondary aerosol formation.

6.
J Phys Chem Lett ; 12(3): 1081-1086, 2021 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-33471530

RESUMEN

Limonene is an abundant monoterpene in the atmosphere and one of the main precursors of secondary organic aerosol. Understanding its interactions with atmospheric molecules is crucial to explain aerosol formation and the various products obtained from competing reaction pathways. Here, using broadband rotational spectroscopy in combination with computational calculations, we show that limonene effectively interacts with water, forming a variety of complexes. Seven different isomers of limonene-H2O, where water and limonene are connected by O-H···π and C-H···O interactions, have been unambiguously identified. Water has been found to preferentially bind to the endocyclic double bond of limonene. Our findings demonstrate a striking ability of water to attach to limonene and enrich our knowledge on the possible interactions of limonene in the atmosphere.


Asunto(s)
Aerosoles/síntesis química , Limoneno/química , Compuestos Orgánicos/síntesis química , Agua/química , Atmósfera/química , Isomerismo
7.
Spectrochim Acta A Mol Biomol Spectrosc ; 249: 119320, 2021 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-33360563

RESUMEN

Non-covalent interactions determine the three-dimensional structure and activity of biological molecules. In this work, the pyrrole-pyridine complex considered as a model of the NH⋯N hydrogen-bonded Watson-Crick base pairs has been generated in a supersonic expansion and characterized by chirped pulse Fourier transform microwave spectroscopy. The analysis of the unconventional spectral pattern of the 1:1 pyrrole-pyridine adduct and its 13C and 15N isotopologues reveal a non-planar complex, with a bent NH⋯N hydrogen bond and large amplitude motion of the pyrrole subunit. The bent structure is likely to arise from the stablishment of the secondary CH⋯N interaction between pyridine and pyrrole moieties.

8.
Phys Chem Chem Phys ; 22(44): 25652-25660, 2020 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-33146180

RESUMEN

The van der Waals 1 : 1 and 1 : 2 adducts between the aromatic molecule pyrrole (Pyr) and the rare gas atom neon (Ne) have been investigated using a combination of chirped pulse Fourier transform microwave spectroscopy and quantum-chemical calculations. Rotational spectra of two and three isotopologues of Pyr-Ne and Pyr-Ne2, respectively, arising from the combinations of the 20Ne and 22Ne isotopes, were identified and a partial rs structure determined. Unusual spectral intensities have been observed with a significant enrichment of heavier isotopic species in the jet molecular expansion. The observed rotational constants of Pyr-Ne are consistent with a nearly symmetric prolate top with the Ne atom located above the plane of pyrrole. The trimer presents C2v symmetry with the Ne atoms located one on each side of the ring plane. The experimental 14N nuclear quadrupole coupling constants have been determined for all the isotopologues of Pyr-Ne and Pyr-Ne2 complexes. Similar values to those of isolated pyrrole have been found, which suggests that the electrical gradient field of pyrrole does not change much upon complexation. The observed spectroscopic parameters have been compared with those of other aromatic-rare gas complexes.

9.
Phys Chem Chem Phys ; 22(40): 23019-23027, 2020 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-33043940

RESUMEN

The 1 : 1 adduct of 2,2,2-trifluoroethanol (TFE) with ammonia was investigated using a combination of chirped pulse and cavity-based Fourier transform microwave spectroscopy and computational methods. Rotational spectra of the most stable TFENH3 conformer and seven deuterium and 15N isotopologues were identified, and this led to a determination of partial rs and ro structures. The observed complex exhibits a gauche conformation of TFE with ammonia inserted into the existing intramolecular hydrogen-bonded ring of TFE. The adduct is stabilised by a delicate interplay between the primary O-HN hydrogen-bond and secondary N-HF interactions between TFE and ammonia. Evidence for several internal-dynamics effects was found in the rotational spectra. The ammonia subunit shows an almost free internal rotation. Tunneling between the gauche forms, g+ and g-, of TFE is quenched by the hydrogen-bond interactions with ammonia.

10.
PLoS One ; 14(8): e0220873, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31369647

RESUMEN

[This corrects the article DOI: 10.1371/journal.pone.0205397.].

11.
Phys Chem Chem Phys ; 21(8): 4331-4338, 2019 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-30724272

RESUMEN

The conformational properties of medium-sized rings are of relevance to understand their intramolecular interactions and reactivity. Here we have characterised the conformational landscape of the eight-membered ketone cyclooctanone by broadband rotational spectroscopy in combination with quantum-chemistry calculations. Three conformers, two boat-chair and one twisted boat chair configurations, have been identified and their spectroscopic parameters determined. Cyclooctanone predominantly exists in the global minimum boat-chair conformation, whose bond lengths and angles have been determined for the first time. The relative abundance of the global minimum with respect to the second conformer in the energy ordering, a twisted boat-chair, is 40 : 1 in all carrier gases used in the supersonic expansion. The conformational preferences of cyclooctanone are driven by minimisation of repulsive non-bonded transannular interactions.

12.
Enferm. infecc. microbiol. clín. (Ed. impr.) ; 37(2): 100-108, feb. 2019. tab
Artículo en Español | IBECS | ID: ibc-181149

RESUMEN

Introducción: El diagnóstico tardío (DT) de la infección por el virus de la inmunodeficiencia humana (VIH) (linfocitos CD4<350/μl al diagnóstico de la enfermedad) empeora el pronóstico de los afectados y aumenta las probabilidades de transmisión. El objetivo del presente trabajo fue analizar la prevalencia de DT, identificar las oportunidades diagnósticas perdidas (ODP) y averiguar el nivel asistencial donde se produjeron. Métodos: Estudio retrospectivo, observacional, descriptivo de la población diagnosticada de infección por VIH/sida en el periodo 2011-2015 en Aragón. Se identificaron las ODP durante los 3 años previos al diagnóstico de la enfermedad en todos los niveles asistenciales, así como la frecuentación asistencial. Se analizaron las condiciones indicadoras (CI) que generaron más ODP, según las últimas recomendaciones para el diagnóstico precoz del VIH en el medio sanitario. Resultados: Se analizaron 435 nuevos casos de VIH/sida. El 45,1% fueron diagnosticados en Atención Primaria (AP). El 49,4% presentaron criterios de DT y el 61,1% se contagiaron vía heterosexual. La mayor parte de ODP (68,5%) se dieron en AP. Las CI que generaron más ODP fueron la dermatitis seborreica/exantema (19,4%) y la fiebre sin causa aparente (10,3%). Sin embargo, las CI que se asociaron a mayor DT fueron la neumonía adquirida en la comunidad y la pérdida de peso injustificada. Conclusión: En Aragón, la prevalencia de DT es elevada, la principal vía de transmisión es la heterosexual y la mayor parte de las CI pasan desapercibidas en AP. La difusión de las guías actuales para solicitar una prueba de VIH orientada por CI y el screening VIH en todo preoperatorio es una medida eficaz para disminuir el DT


Introduction: Late Diagnosis (LD) of Human Immunodeficiency Virus (HIV) infection (CD4 lymphocytes <350/μl at diagnosis of the disease), deteriorates the condition of those affected and increases the probability of transmission. The objective of the present study was to analyse the prevalence of LD, to identify missed diagnostic opportunities (MDO) and to find out which level of the health care delivery system they took place. Methods: Retrospective, observational and descriptive study of the population diagnosed with infection of HIV/AIDS in the period 2011-2015 in Aragon. MDO were identified during the 3 years prior to diagnosis of the disease in all levels of the health care delivery system as well as frequentation of consultations. The indicator conditions (IC) that generated more MDO were analysed according to the latest recommendations for early diagnosis of HIV in the health care setting. Results: 435 newly diagnosed HIV/AIDS cases were analysed. 45.1% were diagnosed in Primary Healthcare (PH). 49.4% presented criteria of LD and 61.1% were infected through heterosexual contact. The majority of MDO (68.5%) were given in PH. The IC that generated the most MDO were seborrheic dermatitis/exanthema (19.4%) and fever of unknown origin (10.3%). However, the IC that were associated with higher LD were pneumonia acquired in the community and unjustified weight loss. Conclusion: In Aragon, prevalence of LD is high, the main route of infection is heterosexual and most of MDO go unnoticed in PH. The dissemination of current guidelines for requesting IC guided HIV testing and HIV screening across the preoperative period will result in an effective measure to decrease the LD


Asunto(s)
Humanos , Masculino , Femenino , Recién Nacido , Lactante , Preescolar , Niño , Adolescente , Adulto Joven , Adulto , Diagnóstico Tardío , Infecciones por VIH/diagnóstico , Persona de Mediana Edad , Dermatitis Seborreica , Diagnóstico Precoz , Emigrantes e Inmigrantes/estadística & datos numéricos , Eritema/epidemiología , Fiebre de Origen Desconocido
13.
Phys Chem Chem Phys ; 21(6): 2938-2945, 2019 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-30675879

RESUMEN

New atomic-level experimental data on the intermolecular non-covalent interactions between a common odorant and a relevant residue at odorant binding sites are reported. The preferred arrangements and binding interactions of fenchone, a common odorant and ethanol, a mimic of serine's side chain, have been unambiguously identified using a combination of high resolution rotational spectroscopy and computational methods. The observed conformers include homochiral (RR) and heterochiral (RS) conformers, with a slight preference for a heterochiral form, and exhibit primary OH-O hydrogen bonds between fenchone and ethanol. Secondary interactions play a key role in determining the relative configurations of fenchone and ethanol, and in shaping quite a flat potential energy surface, with many conformers close in energy and small barriers for interconversion.

14.
Enferm Infecc Microbiol Clin (Engl Ed) ; 37(2): 100-108, 2019 Feb.
Artículo en Inglés, Español | MEDLINE | ID: mdl-29724618

RESUMEN

INTRODUCTION: Late Diagnosis (LD) of Human Immunodeficiency Virus (HIV) infection (CD4 lymphocytes <350/µl at diagnosis of the disease), deteriorates the condition of those affected and increases the probability of transmission. The objective of the present study was to analyse the prevalence of LD, to identify missed diagnostic opportunities (MDO) and to find out which level of the health care delivery system they took place. METHODS: Retrospective, observational and descriptive study of the population diagnosed with infection of HIV/AIDS in the period 2011-2015 in Aragon. MDO were identified during the 3 years prior to diagnosis of the disease in all levels of the health care delivery system as well as frequentation of consultations. The indicator conditions (IC) that generated more MDO were analysed according to the latest recommendations for early diagnosis of HIV in the health care setting. RESULTS: 435 newly diagnosed HIV/AIDS cases were analysed. 45.1% were diagnosed in Primary Healthcare (PH). 49.4% presented criteria of LD and 61.1% were infected through heterosexual contact. The majority of MDO (68.5%) were given in PH. The IC that generated the most MDO were seborrheic dermatitis/exanthema (19.4%) and fever of unknown origin (10.3%). However, the IC that were associated with higher LD were pneumonia acquired in the community and unjustified weight loss. CONCLUSION: In Aragon, prevalence of LD is high, the main route of infection is heterosexual and most of MDO go unnoticed in PH. The dissemination of current guidelines for requesting IC guided HIV testing and HIV screening across the preoperative period will result in an effective measure to decrease the LD.


Asunto(s)
Diagnóstico Tardío , Infecciones por VIH/diagnóstico , Evaluación de Síntomas , Adolescente , Adulto , Niño , Preescolar , Dermatitis Seborreica/epidemiología , Diagnóstico Precoz , Emigrantes e Inmigrantes/estadística & datos numéricos , Eritema/epidemiología , Femenino , Fiebre de Origen Desconocido/epidemiología , Infecciones por VIH/congénito , Infecciones por VIH/epidemiología , Infecciones por VIH/transmisión , Humanos , Incidencia , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Aceptación de la Atención de Salud , Neumonía/epidemiología , Prevalencia , Atención Primaria de Salud , Estudios Retrospectivos , España/epidemiología , Pérdida de Peso , Adulto Joven
15.
Chemistry ; 25(9): 2288-2294, 2019 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-30421558

RESUMEN

The simplest non-proteinogenic amino acid α-aminoisobutyric acid (Aib), an analogue of glycine and alanine, has been vaporized by laser ablation and probed by high-resolution Fourier transform microwave spectroscopic techniques. Comparison of the experimental rotational and 14 N nuclear quadrupole constants with that predicted ab initio has allowed the identification of three conformers of Aib exhibiting three types of hydrogen-bond interactions I (NH⋅⋅⋅O=C, cis-COOH), II (OH⋅⋅⋅N, trans-COOH), and III (N-H⋅⋅⋅O-H, cis-COOH) within the amino acid backbone. The observation of conformer III, not detected previously for related proteinogenic amino acids with a nonpolar side chain in a supersonic expansion, indicates that the presence of the methyl groups should restrict the conformational relaxation from conformer Aib-III to Aib-I. For conformer Aib-II, the rotational spectra of the 13 C isotopomers reveal a tunneling motion arising from the two equivalent methyl groups in the molecule. The observation of a single spectrum at the midpoint between those predicted for the two 13 C of the methyl groups has been explained by considering a double-minimum potential function with a low-energy interconversion barrier for a large amplitude internal motion. This singular fact has been corroborated by the anomalous centrifugal distortion effects determined in conformer Aib-II.


Asunto(s)
Ácidos Aminoisobutíricos , Alanina/análogos & derivados , Ácidos Aminoisobutíricos/química , Glicina/análogos & derivados , Enlace de Hidrógeno , Conformación Molecular
16.
PLoS One ; 13(10): e0205397, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30321206

RESUMEN

PURPOSE: A method for automatically quantifying emphysema regions using High-Resolution Computed Tomography (HRCT) scans of patients with chronic obstructive pulmonary disease (COPD) that does not require manually annotated scans for training is presented. METHODS: HRCT scans of controls and of COPD patients with diverse disease severity are acquired at two different centers. Textural features from co-occurrence matrices and Gaussian filter banks are used to characterize the lung parenchyma in the scans. Two robust versions of multiple instance learning (MIL) classifiers that can handle weakly labeled data, miSVM and MILES, are investigated. Weak labels give information relative to the emphysema without indicating the location of the lesions. The classifiers are trained with the weak labels extracted from the forced expiratory volume in one minute (FEV1) and diffusing capacity of the lungs for carbon monoxide (DLCO). At test time, the classifiers output a patient label indicating overall COPD diagnosis and local labels indicating the presence of emphysema. The classifier performance is compared with manual annotations made by two radiologists, a classical density based method, and pulmonary function tests (PFTs). RESULTS: The miSVM classifier performed better than MILES on both patient and emphysema classification. The classifier has a stronger correlation with PFT than the density based method, the percentage of emphysema in the intersection of annotations from both radiologists, and the percentage of emphysema annotated by one of the radiologists. The correlation between the classifier and the PFT is only outperformed by the second radiologist. CONCLUSIONS: The presented method uses MIL classifiers to automatically identify emphysema regions in HRCT scans. Furthermore, this approach has been demonstrated to correlate better with DLCO than a classical density based method or a radiologist, which is known to be affected in emphysema. Therefore, it is relevant to facilitate assessment of emphysema and to reduce inter-observer variability.


Asunto(s)
Interpretación de Imagen Asistida por Computador/métodos , Pulmón/diagnóstico por imagen , Enfisema Pulmonar/diagnóstico , Tomografía Computarizada por Rayos X , Humanos , Distribución Normal , Enfisema Pulmonar/diagnóstico por imagen , Pruebas de Función Respiratoria
17.
Chemistry ; 24(51): 13408-13412, 2018 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-30066382

RESUMEN

Conformational flexibility and non-covalent interactions determine the structure and activity of molecules in biological processes. In this work, the hydrogen bonding networks of the polyol ribitol have been determined for the first time using a combination of laser ablation and broadband rotational spectroscopy. Five conformations of ribitol have been identified, two with extended carbon chains and three with bent chains. All conformations are stabilized by sequential hydrogen bonding networks of either four or five intramolecular O-H⋅⋅⋅O bonds in a clockwise or counter-clockwise arrangement. The hydrogen bonding patterns are related to the extended or bent-chain conformations of ribitol, and involve 2OH-4OH or 2OH-5OH linkages, respectively. Interestingly, all hydrogen bonds wrap round the carbon backbone of ribitol rather than being located above or below it as it happens for other polyols and cyclic sugars.

18.
IEEE J Biomed Health Inform ; 22(5): 1486-1496, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29990220

RESUMEN

Chronic obstructive pulmonary disease (COPD) is a lung disease that can be quantified using chest computed tomography scans. Recent studies have shown that COPD can be automatically diagnosed using weakly supervised learning of intensity and texture distributions. However, up till now such classifiers have only been evaluated on scans from a single domain, and it is unclear whether they would generalize across domains, such as different scanners or scanning protocols. To address this problem, we investigate classification of COPD in a multicenter dataset with a total of 803 scans from three different centers, four different scanners, with heterogenous subject distributions. Our method is based on Gaussian texture features, and a weighted logistic classifier, which increases the weights of samples similar to the test data. We show that Gaussian texture features outperform intensity features previously used in multicenter classification tasks. We also show that a weighting strategy based on a classifier that is trained to discriminate between scans from different domains can further improve the results. To encourage further research into transfer learning methods for the classification of COPD, upon acceptance of this paper we will release two feature datasets used in this study on http://bigr.nl/research/projects/copd.


Asunto(s)
Interpretación de Imagen Asistida por Computador/métodos , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Adulto , Anciano , Área Bajo la Curva , Humanos , Aprendizaje Automático , Persona de Mediana Edad
19.
J Matern Fetal Neonatal Med ; 31(13): 1748-1755, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28532280

RESUMEN

OBJECTIVE: To describe fetal and neonatal mortality due to congenital anomalies in Colombia. METHODS: We analyzed all fetal and neonatal deaths due to a congenital anomaly registered with the Colombian vital statistics system during 1999-2008. RESULTS: The registry included 213,293 fetal deaths and 7,216,727 live births. Of the live births, 77,738 (1.08%) resulted in neonatal deaths. Congenital anomalies were responsible for 7321 fetal deaths (3.4% of all fetal deaths) and 15,040 neonatal deaths (19.3% of all neonatal deaths). The fetal mortality rate due to congenital anomalies was 9.9 per 10,000 live births and fetal deaths; the neonatal mortality rate due to congenital anomalies was 20.8 per 10,000 live births. Mortality rates due to congenital anomalies remained relatively stable during the study period. The most frequent fatal congenital anomalies were congenital heart defects (32.0%), central nervous system anomalies (15.8%), and chromosomal anomalies (8.0%). Risk factors for fetal and neonatal death included: male or undetermined sex, living in villages or rural areas, mother's age >35 years, low and very low birthweight, and <28 weeks gestation at birth. CONCLUSIONS: Congenital anomalies are an important cause of fetal and neonatal deaths in Colombia, but many of the anomalies may be preventable or treatable.


Asunto(s)
Anomalías Congénitas/mortalidad , Mortalidad Infantil/tendencias , Mortalidad Perinatal/tendencias , Adulto , Colombia/epidemiología , Femenino , Humanos , Lactante , Recien Nacido con Peso al Nacer Extremadamente Bajo , Recien Nacido Extremadamente Prematuro , Recién Nacido , Masculino , Vigilancia de la Población , Embarazo , Sistema de Registros , Factores de Riesgo , Población Rural , Factores Sexuales , Adulto Joven
20.
Oncología (Guayaquil) ; 27(3): 218-227, 30 diciembre 2017.
Artículo en Español | LILACS | ID: biblio-998925

RESUMEN

Introducción: La implementación de las pruebas moleculares para la detección de la infección por hrHPV ha generado cambios en las directrices del tamizaje en la detección oportuna del carcinoma cervicouterino. El objetivo del estudio es presentar la sensibilidad y especificidad de los estudios citológicos y las pruebas moleculares con los estudios histológicos. Métodos: Se realizó un estudio transversal, retrospectivo en el hospital de Solca-Quito de enero a diciembre 2014. Se recolectaron los casos con los diagnósticos citológicos cervicouterinos, los resultados de la prueba de PCR tiempo real de hrHPV (Hibribio®) y los diagnósticos histopatológicos en las pacientes a las que se realizó biopsia. El análisis realizado fue "de prueba diagnóstica" para medir la sensibilidad y especificidad de las pruebas. Resultados: 730 estudios moleculares de hrHPV conjuntamente con estudios citológicos fueron realizados. Los casos positivos para hrHPV fueron 301/730 casos (41.2 %). La mayoría de casos hrHPV positivos corresponde a los genotipos 16/18 (59.5 %) y se encuentra en los rangos de edad entre 30 y 49 años (58.8 %). En 168 casos se realizó además estudio histopatológico, en los que se determinó la sensibilidad (S) de la citología Vs Histología la cual fue de 76 %, la especificidad (E) fue de 48 %, con un valor predictivo positivo (VPP) de 90 %. La S de HrHPV vs Histología fue de 74%, E 39 %, VPP 89 %; la S de Citología + HrHVP vs Histología fue de 91 %, E 40 %, VPP 90 %. Conclusión: La mayor sensibilidad para el diagnóstico de cáncer cervicouterino la realización de la Citología y la presencia de HrHVP. La mayor especificidad se consiguió con el estudio de Citología.


Introduction: The implementation of molecular tests for the detection of hrHPV infection has generated changes in the screening guidelines in the timely detection of cervical carcinoma. The aim of the study is to present the sensitivity and specificity of cytological studies and molecular tests with histological studies. Methods: A cross-sectional, retrospective study was carried out in the Solca-Quito hospital from January to December 2014. Cases were collected with cervical cytological diagnoses, the results of the real-time PCR test of hrHPV (Hibribio®) and the diagnoses Histopathological findings in patients who underwent a biopsy. The analysis performed was "diagnostic test" to measure the sensitivity and specificity of the tests. Results: 730 molecular studies of hrHPV in conjunction with cytological studies were performed. The positive cases for hrHPV were 301/730 cases (41.2 %). The majority of hrHPV positive cases correspond to genotypes 16/18 (59.5 %) and are in the age ranges between 30 and 49 years (58.8 %). In 168 cases, a histopathological study was also carried out, in which the sensitivity (S) of the cytology Vs Histology was determined, which was 76 %, the specificity (E) was 48 %, with a positive predictive value (PPV) of 90 % The S of HrHPV vs Histology was 74%, E 39%, PPV 89 %; S for Cytology + HrHVP vs Histology was 91 %, E 40 %, PPV 90 %. Conclusion: The highest sensitivity for the diagnosis of cervical cancer is the completion of Cytology and the presence of HrHVP. The highest specificity was obtained with the Cytology study.


Asunto(s)
Humanos , Femenino , Adulto , Persona de Mediana Edad , Neoplasias del Cuello Uterino , Sensibilidad y Especificidad , Biología Celular , Infecciones por Papillomavirus , Lesiones Intraepiteliales Escamosas de Cuello Uterino
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