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1.
Plant Divers ; 46(1): 39-48, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38343600

RESUMEN

Data gaps and biases are two important issues that affect the quality of biodiversity information and downstream results. Understanding how best to fill existing gaps and account for biases is necessary to improve our current information most effectively. Two current main approaches for obtaining and improving data include (1) curation of biological collections, and (2) fieldwork. However, the comparative effectiveness of these approaches in improving biodiversity data remains little explored. We used the Flora de Bogotá project to study the magnitude of change in species richness, spatial coverage, and sample coverage of plant records based on curation versus fieldwork. The process of curation resulted in a decrease in species richness (synonym and error removal), but it significantly increased the number of records per species. Fieldwork contributed to a slight increase in species richness, via accumulation of new records. Additionally, curation led to increases in spatial coverage, species observed by locality, the number of plant records by species, and localities by species compared to fieldwork. Overall, curation was more efficient in producing new information compared to fieldwork, mainly because of the large number of records available in herbaria. We recommend intensive curatorial work as the first step in increasing biodiversity data quality and quantity, to identify bias and gaps at the regional scale that can then be targeted with fieldwork. The stepwise strategy would enable fieldwork to be planned more cost-effectively given the limited resources for biodiversity exploration and characterization.

2.
Lancet Glob Health ; 11(3): e350-e360, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36796982

RESUMEN

BACKGROUND: Colposcopy, currently included in WHO recommendations as an option to triage human papillomavirus (HPV)-positive women, remains as the reference standard to guide both biopsy for confirmation of cervical precancer and cancer and treatment approaches. We aim to evaluate the performance of colposcopy to detect cervical precancer and cancer for triage in HPV-positive women. METHODS: This cross-sectional, multicentric screening study was conducted at 12 centres (including primary and secondary care centres, hospitals, laboratories, and universities) in Latin America (Argentina, Bolivia, Colombia, Costa Rica, Honduras, Mexico, Paraguay, Peru, and Uruguay). Eligible women were aged 30-64 years, sexually active, did not have a history of cervical cancer or treatment for cervical precancer or a hysterectomy, and were not planning to move outside of the study area. Women were screened with HPV DNA testing and cytology. HPV-positive women were referred to colposcopy using a standardised protocol, including biopsy collection of observed lesions, endocervical sampling for transformation zone (TZ) type 3, and treatment as needed. Women with initial normal colposcopy or no high-grade cervical lesions on histology (less than cervical intraepithelial neoplasia [CIN] grade 2) were recalled after 18 months for another HPV test to complete disease ascertainment; HPV-positive women were referred for a second colposcopy with biopsy and treatment as needed. Diagnostic accuracy of colposcopy was assessed by considering a positive test result when the colposcopic impression at the initial colposcopy was positive minor, positive major, or suspected cancer, and was considered negative otherwise. The main study outcome was histologically confirmed CIN3+ (defined as grade 3 or worse) detected at the initial visit or 18-month visit. FINDINGS: Between Dec 12, 2012, and Dec 3, 2021, 42 502 women were recruited, and 5985 (14·1%) tested positive for HPV. 4499 participants with complete disease ascertainment and follow-up were included in the analysis, with a median age of 40·6 years (IQR 34·7-49·9). CIN3+ was detected in 669 (14·9%) of 4499 women at the initial visit or 18-month visit (3530 [78·5%] negative or CIN1, 300 [6·7%] CIN2, 616 [13·7%] CIN3, and 53 [1·2%] cancers). Sensitivity was 91·2% (95% CI 88·9-93·2) for CIN3+, whereas specificity was 50·1% (48·5-51·8) for less than CIN2 and 47·1% (45·5-48·7) for less than CIN3. Sensitivity for CIN3+ significantly decreased in older women (93·5% [95% CI 91·3-95·3] in those aged 30-49 years vs 77·6% [68·6-85·0] in those aged 50-65 years; p<0·0001), whereas specificity for less than CIN2 significantly increased (45·7% [43·8-47·6] vs 61·8% [58·7-64·8]; p<0·0001). Sensitivity for CIN3+ was also significantly lower in women with negative cytology than in those with abnormal cytology (p<0·0001). INTERPRETATION: Colposcopy is accurate for CIN3+ detection in HPV-positive women. These results reflect ESTAMPA efforts in an 18-month follow-up strategy to maximise disease detection with an internationally validated clinical management protocol and regular training, including quality improvement practices. We showed that colposcopy can be optimised with proper standardisation to be used as triage in HPV-positive women. FUNDING: WHO; Pan American Health Organization; Union for International Cancer Control; National Cancer Institute (NCI); NCI Center for Global Health; National Agency for the Promotion of Research, Technological Development, and Innovation; NCI of Argentina and Colombia; Caja Costarricense de Seguro Social; National Council for Science and Technology of Paraguay; International Agency for Research on Cancer; and all local collaborative institutions.


Asunto(s)
Infecciones por Papillomavirus , Displasia del Cuello del Útero , Neoplasias del Cuello Uterino , Femenino , Humanos , Embarazo , Anciano , Adulto , Persona de Mediana Edad , Virus del Papiloma Humano , Colposcopía , Infecciones por Papillomavirus/diagnóstico , Triaje , Estudios Transversales , Detección Precoz del Cáncer/métodos , Displasia del Cuello del Útero/diagnóstico , Neoplasias del Cuello Uterino/diagnóstico , Tamizaje Masivo/métodos , Frotis Vaginal
3.
Ecol Evol ; 13(1): e9736, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36694555

RESUMEN

Using the genus Casearia, we assessed the status of nested singletons: individual specimens corresponding to accepted species but in molecular trees appearing nested within clades of closely related species. Normally, such cases would be left undecided, while on the other hand, timely taxonomic decisions are required. We argue that morphological, chorological, and ecological data can be informative to illuminate patterns of speciation. Their use can provide a first step in testing taxon concepts at species level. We focused on five cases of nested singletons in trees of the genus Casearia. We employed PCA and cluster analysis to assess phenotypic differentiation. Using geocoordinates, we calculated niche space differentiation based on 19 bioclim variables, by means of PCA and niche equivalency and similarity tests and generated dot maps. We found that the singletons were morphologically distinctive in two of the five cases (Casearia selloana and C. manausensis), relatively distinctive in two other cases (C. zizyphoides and C. mariquitensis), and partially overlapping in the last case (C. grandiflora). For two cases (C. mariquitensis and C. selloana), ecological niche space was broadly overlapping, in two cases it was found broadly nested (C. grandiflora and C. zizyphoides), and in one case narrowly nested (C. manausensis), but in no case niche differentiation was observed. Niche overlap, similarity and equivalency showed corresponding patterns. Given these data, one would interpret C. selloana and C. manausensis as presumably well-distinguished taxa, their narrow distribution ranges suggesting recently emerging lineages. The other three cases are not clearcut. Morphological data would suggest particularly C. grandiflora conspecific with C. arborea, but differences in the distribution are intriguing. Our approach would reject the notion of potential synonymy based on nested phylogenetic placement for at least two of the five cases. The other case also shows no complete lack of differentiation which would support synonymy.

4.
Int J Cancer ; 152(8): 1581-1592, 2023 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-36451311

RESUMEN

VIA is recommended for triage of HPV-positive women attending cervical screening. In the multicentric ESTAMPA study, VIA performance for detection of cervical intraepithelial neoplasia grade 3 or worse (CIN3+) among HPV-positive women was evaluated. Women aged 30-64 years were screened with HPV testing and cytology and referred to colposcopy if either test was positive. At colposcopy visit, study-trained midwives/nurses/GPs performed VIA ahead of colposcopy. VIA was considered positive if acetowhite lesions were observed in or close to the transformation zone. Ablative treatment eligibility was assessed for VIA positives. Performance indicators were estimated. Three thousand one hundred and forty-two HPV-positive women were included. Sensitivity for CIN3+ was 85.9% (95% CI 81.2-89.5) among women <50 years and, although not significant, slightly lower in women 50+ (78.0%, 95% CI 65.9-86.6). Overall specificity was 58.6% (95% CI 56.7-60.5) and was significantly higher among women 50+ (70.3%, 95% CI 66.8-73.5) compared to women <50 (54.3%, 95% CI 52.1-56.5). VIA positivity was lower among women 50+ (35.2%, 95% CI 31.9-38.6) compared to women <50 (53.2, 95% CI 51.1-55.2). Overall eligibility for ablative treatment was 74.5% and did not differ by age. VIA sensitivity, specificity, and positivity, and ablative treatment eligibility varied highly by provider (ranges: 25%-95.4%, 44.9%-94.4%, 8.2%-65.3%, 0%-98.7%, respectively). VIA sensitivity for cervical precancer detection among HPV-positive women performed by trained providers was high with an important reduction in referral rates. However, scaling-up HPV screening triaged by VIA will be challenging due to the high variability of VIA performance and providers' need for training and supervision.


Asunto(s)
Infecciones por Papillomavirus , Displasia del Cuello del Útero , Neoplasias del Cuello Uterino , Femenino , Humanos , Embarazo , Cuello del Útero/patología , Ácido Acético , Triaje , Detección Precoz del Cáncer/métodos , Tamizaje Masivo/métodos , Colposcopía
5.
BMJ Open ; 10(5): e035796, 2020 05 24.
Artículo en Inglés | MEDLINE | ID: mdl-32448795

RESUMEN

INTRODUCTION: Human papillomavirus (HPV) testing is replacing cytology in primary screening. Its limited specificity demands using a second (triage) test to better identify women at high-risk of cervical disease. Cytology represents the immediate triage but its low sensitivity might hamper HPV testing sensitivity, particularly in low-income and middle-income countries (LMICs), where cytology performance has been suboptimal. The ESTAMPA (EStudio multicéntrico de TAMizaje y triaje de cáncer de cuello uterino con pruebas del virus del PApiloma humano; Spanish acronym) study will: (1) evaluate the performance of different triage techniques to detect cervical precancer and (2) inform on how to implement HPV-based screening programmes in LMIC. METHODS AND ANALYSIS: Women aged 30-64 years are screened with HPV testing and Pap across 12 study centres in Latin America. Screened positives have colposcopy with biopsy and treatment of lesions. Women with no evident disease are recalled 18 months later for another HPV test; those HPV-positive undergo colposcopy with biopsy and treatment as needed. Biological specimens are collected in different visits for triage testing, which is not used for clinical management. The study outcome is histological high-grade squamous intraepithelial or worse lesions (HSIL+) under the lower anogenital squamous terminology. About 50 000 women will be screened and 500 HSIL+ cases detected (at initial and 18 months screening). Performance measures (sensitivity, specificity and predictive values) of triage techniques to detect HSIL+ will be estimated and compared with adjustment by age and study centre. ETHICS AND DISSEMINATION: The study protocol has been approved by the Ethics Committee of the International Agency for Research on Cancer (IARC), of the Pan American Health Organisation (PAHO) and by those in each participating centre. A Data and Safety Monitoring Board (DSMB) has been established to monitor progress of the study, assure participant safety, advice on scientific conduct and analysis and suggest protocol improvements. Study findings will be published in peer-reviewed journals and presented at scientific meetings. TRIAL REGISTRATION NUMBER: NCT01881659.


Asunto(s)
Alphapapillomavirus/aislamiento & purificación , Detección Precoz del Cáncer , Infecciones por Papillomavirus/diagnóstico , Triaje , Displasia del Cuello del Útero/diagnóstico , Adulto , Colposcopía , Femenino , Humanos , América Latina , Persona de Mediana Edad , Neoplasias del Cuello Uterino/diagnóstico
6.
Science ; 358(6370): 1614-1617, 2017 12 22.
Artículo en Inglés | MEDLINE | ID: mdl-29269477

RESUMEN

The cataloging of the vascular plants of the Americas has a centuries-long history, but it is only in recent decades that an overview of the entire flora has become possible. We present an integrated assessment of all known native species of vascular plants in the Americas. Twelve regional and national checklists, prepared over the past 25 years and including two large ongoing flora projects, were merged into a single list. Our publicly searchable checklist includes 124,993 species, 6227 genera, and 355 families, which correspond to 33% of the 383,671 vascular plant species known worldwide. In the past 25 years, the rate at which new species descriptions are added has averaged 744 annually for the Americas, and we can expect the total to reach about 150,000.

7.
Proc Natl Acad Sci U S A ; 114(40): 10695-10700, 2017 10 03.
Artículo en Inglés | MEDLINE | ID: mdl-28923966

RESUMEN

Recent debates on the number of plant species in the vast lowland rain forests of the Amazon have been based largely on model estimates, neglecting published checklists based on verified voucher data. Here we collate taxonomically verified checklists to present a list of seed plant species from lowland Amazon rain forests. Our list comprises 14,003 species, of which 6,727 are trees. These figures are similar to estimates derived from nonparametric ecological models, but they contrast strongly with predictions of much higher tree diversity derived from parametric models. Based on the known proportion of tree species in neotropical lowland rain forest communities as measured in complete plot censuses, and on overall estimates of seed plant diversity in Brazil and in the neotropics in general, it is more likely that tree diversity in the Amazon is closer to the lower estimates derived from nonparametric models. Much remains unknown about Amazonian plant diversity, but this taxonomically verified dataset provides a valid starting point for macroecological and evolutionary studies aimed at understanding the origin, evolution, and ecology of the exceptional biodiversity of Amazonian forests.


Asunto(s)
Biodiversidad , Bases de Datos Factuales , Plantas/clasificación , Bosque Lluvioso , Brasil
8.
Accid Anal Prev ; 50: 304-11, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22658462

RESUMEN

This paper presents a spatial and temporal analysis of child pedestrian crash data in Santiago, Chile during the period 2000-2008. First, this study identified seven critical areas with high child pedestrian crash risk employing kernel density estimation, and subsequently, statistically significant clusters of the main attributes associated to these crashes in each critical area were determined in a geographic information systems environment. Moran's I index test identified a positive spatial autocorrelation on crash contributing factors, time of day, straight road sections and intersections, and roads without traffic signs within the critical areas during the studied period, whereas a random spatial pattern was identified for crashes related to the age attribute. No statistical significance in the spatial relationship was obtained in child pedestrian crashes with respect to gender, weekday, and month of the year. The results from this research aid in determining the areas in which enhanced school-age child pedestrian safety is required by developing and implementing effective enforcement, educational, and engineering preventive measures.


Asunto(s)
Accidentes de Tránsito/estadística & datos numéricos , Caminata , Niño , Chile/epidemiología , Femenino , Humanos , Masculino , Factores de Riesgo , Factores Socioeconómicos , Estadísticas no Paramétricas , Factores de Tiempo , Población Urbana
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