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1.
Ultrasound Obstet Gynecol ; 64(4): 538-549, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38477149

RESUMEN

OBJECTIVES: To externally and prospectively validate the International Ovarian Tumor Analysis (IOTA) Simple Rules (SRs), Logistic Regression model 2 (LR2) and Assessment of Different NEoplasias in the adneXa (ADNEX) model in a Portuguese population, comparing these approaches with subjective assessment and the risk-of-malignancy index (RMI), as well as with each other. This study also aimed to retrospectively validate the IOTA two-step strategy, using modified benign simple descriptors (MBDs) followed by the ADNEX model in cases in which MBDs were not applicable. METHODS: This was a prospective multicenter diagnostic accuracy study conducted between January 2016 and December 2021 of consecutive patients with an ultrasound diagnosis of at least one adnexal tumor, who underwent surgery at one of three tertiary referral centers in Lisbon, Portugal. All ultrasound assessments were performed by Level-II or -III sonologists with IOTA certification. Patient clinical data and serum CA 125 levels were collected from hospital databases. Each adnexal mass was classified as benign or malignant using subjective assessment, RMI, IOTA SRs, LR2 and the ADNEX model (with and without CA 125). The reference standard was histopathological diagnosis. In the second phase, all adnexal tumors were classified retrospectively using the two-step strategy (MBDs + ADNEX). Sensitivity, specificity, positive and negative predictive values, positive and negative likelihood ratios and overall accuracy were determined for all methods. Receiver-operating-characteristics curves were constructed and corresponding areas under the curve (AUC) were determined for RMI, LR2, the ADNEX model and the two-step strategy. The ADNEX model calibration plots were constructed using locally estimated scatterplot smoothing (LOESS). RESULTS: Of the 571 patients included in the study, 428 had benign disease and 143 had malignant disease (prevalence of malignancy, 25.0%), of which 42 had borderline ovarian tumor, 93 had primary invasive adnexal cancer and eight had metastatic tumors in the adnexa. Subjective assessment had an overall sensitivity of 97.9% and a specificity of 83.6% for distinguishing between benign and malignant lesions. RMI showed high specificity (95.6%) but very low sensitivity (58.7%), with an AUC of 0.913. The IOTA SRs were applicable in 80.0% of patients, with a sensitivity of 94.8% and specificity of 98.6%. The IOTA LR2 had a sensitivity of 84.6%, specificity of 86.9% and an AUC of 0.939, at a malignancy risk cut-off of 10%. At the same cut-off, the sensitivity, specificity and AUC for the ADNEX model with vs without CA 125 were 95.8% vs 98.6%, 82.5% vs 79.7% and 0.962 vs 0.960, respectively. The ADNEX model gave heterogeneous results for distinguishing between benign masses and different subtypes of malignancy, with the highest AUC (0.991) for discriminating benign masses from primary invasive adnexal cancer Stages II-IV, and the lowest AUC (0.696) for discriminating primary invasive adnexal cancer Stage I from metastatic lesion in the adnexa. The calibration plot suggested underestimation of the risk by the ADNEX model compared with the observed proportion of malignancy. The MBDs were applicable in 26.3% (150/571) of cases, of which none was malignant. The two-step strategy using the ADNEX model in the second step only, with and without CA 125, had AUCs of 0.964 and 0.961, respectively, which was similar to applying the ADNEX model in all patients. CONCLUSIONS: The IOTA methods showed good-to-excellent performance in the Portuguese population, outperforming RMI. The ADNEX model was superior to other methods in terms of accuracy, but interpretation of its ability to distinguish between malignant subtypes was limited by sample size and large differences in the prevalence of tumor subtypes. The IOTA MBDs are reliable in identifying benign disease. The two-step strategy comprising application of MBDs followed by the ADNEX model if MBDs are not applicable, is suitable for daily clinical practice, circumventing the need to calculate the risk of malignancy in all patients. © 2024 International Society of Ultrasound in Obstetrics and Gynecology.


Asunto(s)
Enfermedades de los Anexos , Neoplasias Ováricas , Ultrasonografía , Humanos , Femenino , Portugal , Estudios Retrospectivos , Estudios Prospectivos , Persona de Mediana Edad , Enfermedades de los Anexos/diagnóstico por imagen , Ultrasonografía/métodos , Adulto , Neoplasias Ováricas/diagnóstico por imagen , Neoplasias Ováricas/patología , Neoplasias Ováricas/clasificación , Neoplasias Ováricas/sangre , Sensibilidad y Especificidad , Anciano , Antígeno Ca-125/sangre , Curva ROC , Modelos Logísticos , Valor Predictivo de las Pruebas , Reproducibilidad de los Resultados , Diagnóstico Diferencial
2.
Drug Alcohol Depend ; 223: 108706, 2021 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-33901753

RESUMEN

BACKGROUND: Substance use-related stigma is a significant barrier to care among persons who use drugs (PWUD). Less is known regarding how intersectional identities, like gender, shape experiences of substance use-related stigma. We sought to answer the following question: Do men or women PWUD experience more drug use stigma? METHODS: Data were drawn from a systematic review of the global, peer-reviewed scientific literature on substance use-related stigma conducted through 2017 and guided by the Stigma and Substance Use Process Model and PRISMA guidelines. Articles were included in the present analysis if they either qualitatively illustrated themes related to the gendered nature of drug use-related stigma, or quantitatively tested the moderating effect of gender on drug use-related stigma. RESULTS: Of the 75 studies included, 40 (53 %) were quantitative and 35 (47 %) were qualitative. Of the quantitative articles, 22 (55 %) found no association between gender and drug use-related stigma, 4 (10 %) identified women who use drugs (WWUD) were more stigmatized, and 2 (5 %) determined men who use drugs (MWUD) were more stigmatized. In contrast, nearly all (34; 97 %) of the qualitative articles demonstrated WWUD experienced greater levels of drug use-related stigma. CONCLUSION: The quantitative literature is equivocal regarding the influence of gender on drug use-related stigma, but the qualitative literature more clearly demonstrates WWUD experience greater levels of stigma. The use of validated drug use-related stigma measures and the tailoring of stigma scales to WWUD are needed to understand the role of stigma in heightening the disproportionate harms experienced by WWUD.


Asunto(s)
Preparaciones Farmacéuticas , Trastornos Relacionados con Sustancias , Femenino , Identidad de Género , Humanos , Masculino , Estigma Social , Trastornos Relacionados con Sustancias/epidemiología
3.
Math Biosci ; 295: 48-54, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-29104133

RESUMEN

Geometrical Singular Perturbation Theory has been successful to investigate a broad range of biological problems with different time scales. The aim of this paper is to apply this theory to a predator-prey model of modified Leslie-Gower type for which we consider that prey reproduces mush faster than predator. This naturally leads to introduce a small parameter ϵ which gives rise to a slow-fast system. This system has a special folded singularity which has not been analyzed in the classical work [15]. We use the blow-up technique to visualize the behavior near this fold point P. Outside of this region the dynamics are given by classical regular and singular perturbation theory. This allows to quantify geometrically the attractive limit-cycle with an error of O(ϵ) and shows that it exhibits the canard phenomenon while crossing P.


Asunto(s)
Modelos Biológicos , Conducta Predatoria , Animales , Cadena Alimentaria , Conceptos Matemáticos , Dinámica Poblacional
4.
Acta Biotheor ; 64(4): 311-325, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27770317

RESUMEN

This article is devoted to the characterization of the basin of attraction of pattern solutions for some slow-fast reaction-diffusion systems with a symmetric property and an underlying oscillatory reaction part. We characterize some subsets of initial conditions that prevent the dynamical system to evolve asymptotically toward solutions which are homogeneous in space. We also perform numerical simulations that illustrate theoretical results and give rise to symmetric and non-symmetric pattern solutions. We obtain these last solutions by choosing particular random initial conditions.


Asunto(s)
Simulación por Computador , Matemática , Modelos Teóricos , Análisis Numérico Asistido por Computador , Difusión , Cinética
5.
Ann Hum Biol ; 37(1): 86-107, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-19939195

RESUMEN

BACKGROUND: Gene flow among human populations is generally interpreted in terms of complex patterns, with the observed gene frequencies being the consequence of the entire genetic and demographic histories of the population. AIMS: This study performs a high-resolution analysis of the Y-chromosome haplogroup E in Western Andalusians (Huelva province). The genetic information presented here provides new insights into migration processes that took place throughout the Mediterranean space and tries to evaluate its impact on the current genetic composition of the most southwestern population of Spain. SUBJECTS AND METHODS: 167 unrelated males were previously typed for the presence/absence of the Y-chromosome Alu polymorphism (YAP). The group of YAP (+) Andalusians was genotyped for 16 Y-SNPs and also characterized for 16 Y-STR loci. RESULTS: The distribution of E-M81 haplogroup, a Berber marker, was found at a frequency of 3% in our sample. The distribution of M81 frequencies in Iberia seems to be not concordant with the regions where Islamic rule was most intense and long-lasting. The study also showed that most of M78 derived allele (6.6%) led to the V13* subhaplogroup. We also found the most basal and rare paragroup M78* and others with V12 and V65 mutations. The lineage defined by M34 mutation, which is quite frequent in Jews, was detected as well. CONCLUSIONS: The haplogroup E among Western Andalusians revealed a complex admixture of genetic markers from the Mediterranean space, with interesting signatures of populations from the Middle East and the Balkan Peninsula and a surprisingly low influence by Berber populations compared to other areas of the Iberian Peninsula.


Asunto(s)
Cromosomas Humanos Y/genética , Genética de Población , Haplotipos , Marcadores Genéticos , Humanos , Masculino , Polimorfismo de Nucleótido Simple , España/etnología
6.
Ann Hum Genet ; 73(2): 184-95, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19133940

RESUMEN

Inbreeding patterns over the past two centuries have been studied more extensively in Spain and Italy than anywhere else in Europe. Consanguinity studies in mainland Spain have shown that populations settled along the Cantabrian cornice share inbreeding patterns that distinguish them from other populations further south. A visual representation of spatial variations of two key inbreeding variables is presented here for the first time via contour maps. This paper also analyzes time trends of mean inbreeding coefficients for X-linked (F(x)) and autosomal genes (F) (1862-1995) together with variations in F(x)/F ratios in Guipúzcoa, the most autochthonous Spanish Basque province. Because close cousin marriages are a mark of identity of the study population, we evaluated the contribution of uncle-niece/aunt-nephew (M12) and first cousin (M22) marriages to F(x) and F values and compared the frequencies of M12 and M22 pedigree subtypes and their corresponding F(x)/F ratios to those found in other Spanish populations. The mean Fx and F inbreeding levels in Guipúzcoa for the 134-year period analyzed were 1.51 x 10(-3) and 1.04 x 10(-3), respectively, and the F(x)/F ratio was seen to be very stable over time. Our findings show that major similarities exist for close consanguineous marriage subtypes between Basque and non-Basque Spanish populations, despite significant geographic variability in terms of first cousin pedigrees. The distortion seems to be caused by Guipúzcoa. The F(x)/F ratios for first cousins in Spanish populations were higher than expected (1.25), with values ranging from 1.34 to 1.48. The findings of the present study may be useful for advancing knowledge on the effects of the interaction between biology and culture and for exploring associations between mating patterns and the prevalence of certain diseases.


Asunto(s)
Consanguinidad , Genes Ligados a X , Genes , Genética de Población , Cromosomas , Cultura , Femenino , Humanos , Masculino , Matrimonio , España
7.
Hum Biol ; 78(6): 663-79, 2006 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17564246

RESUMEN

An understanding of population relationships in the Mediterranean region is crucial to the reconstruction of recent human evolution. Andalusia, the most southern region of Spain, has been continuously and densely occupied since ancient times and has a rich history of contacts with many different Mediterranean populations. Thus, to understand the Mediterranean peopling process, investigators should analyze the population relationships between the Iberian peninsula and northern Africa based on an assessment of genetic diversity that takes Andalusia into consideration. The aim of this study was to address the extent of genetic variation in the Iberian peninsula between its geographic extremes (Huelva and the Basque area) and to explain the intensity of the phylogenetic relationships between Andalusians and other neighboring populations, such as those from North Africa. We present, for the first time, results on allotype markers (GM and KM) of human immunoglobulins in the Andalusian population from Huelva. The most frequent GM haplotypes in Andalusia correspond to those that are also the most common in Europe. A sub-Saharan haplotype was found at a relatively high frequency compared to other Iberian samples, and a North Asian marker did not reach polymorphic frequencies in the study sample. A hierarchical cluster analysis based on the first two principal components (94.1% of the total genetic variance) revealed an interesting geographic structure for the 49 populations selected from the literature. The Huelva sample showed a central position in the multivariate space--despite being geographically located at one of the extremes of the Mediterranean basin--and clustered with most Western European populations. Western Europe and Eastern Europe (the latter group paradoxically including Italy and the major islands of the western Mediterranean) were differentiated. North African populations were grouped in two clusters that did not separate either Arabs and Berbers or their present-day countries. Analysis of immunoglobulin allotype markers shows that gene flow among human populations should generally be interpreted in terms of complex patterns, with the observed frequencies being the consequence of the entire genetic and demographic history of the population. Single historical events rarely determine gene frequencies in large human populations. Analysis of the GM system has shown that the Andalusian population from Huelva, as a result of its complex history, is not simply an outstanding part of the Mediterranean world but rather the genetic center of gravity of that world.


Asunto(s)
Frecuencia de los Genes , Variación Genética/genética , Genética de Población/estadística & datos numéricos , Alotipos de Inmunoglobulina Gm/genética , Alotipos Km de Inmunoglobulina/genética , África del Norte , Población Negra , Análisis por Conglomerados , Marcadores Genéticos , Geografía , Humanos , Inmunoglobulinas/genética , Región Mediterránea , Fenotipo , Filogenia , Polimorfismo Genético , España , Población Blanca
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