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1.
Sci Total Environ ; 905: 167873, 2023 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-37852497

RESUMEN

The objective of this investigation is to evaluate the recent changes in the accumulation of organic matter and carbon on the Yahuarcaca lake system, by means of a multiproxy paleolimnological study. The methodology based on lithological descriptions of 210Pb/137Cs-dated cores allowed us to infer the centennial sedimentation processes and carbon accumulation rates. Sedimentary facies, grain size, magnetic susceptibility, loss on ignition, carbonate, chlorophyll derivatives, stable isotopes of δ13C/δ15N, and carbon accumulation rate were analyzed. LANDSAT and photographic record of satellite images were used to reconstruct the historical geomorphological evolution of the Lake. Sediment cores yielded basal ages of 1827 and 1828 Common Era, representing the formation of lakes as a consequence of the Amazon meandering process. Two main paleolimnological stages were identified, with a boundary transition set at 1980-1984 Common Era, attributed to the geomorphological closure and complete lake separation from the Amazon and the onset of full lentic conditions. This inference was mainly based on both sharp increases in the sedimentation rate from 0.2 to >1 cm yr-1 and carbon accumulation that increased seven-fold (from 2 to 14 g m-2 yr-1) from 1980 to 1984 Common Era. The flood-pulse and connection to the Amazon defined the magnitude of organic inputs, where areas more distant/isolated from the river showed higher accumulation of carbon from autochthonous production, with an average of 8.9 % and 1.10 g m-2 yr-1 (carbon accumulation rate). Those areas closer and connected to the river were strongly related to the interannual hydrological variability, with a lower mean carbon content (5.9 %) and 0.73 g m-2 yr-1 (carbon accumulation rate). We concluded that carbon burial was highest within the most distant spot from the Amazon River because of the weaker connection to the river itself and the more stable lentic conditions for net sedimentation.

2.
Ultrasound Obstet Gynecol ; 50(3): 395-403, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27706929

RESUMEN

OBJECTIVE: Transvaginal sonography (TVS) and serum biomarkers are used widely in clinical practice to triage women with adnexal masses, but the effectiveness of current biomarkers is weak. The aim of this study was to determine the best method of diagnosing patients with adnexal masses, in terms of diagnostic accuracy and economic costs, among four triage strategies: (1) the International Ovarian Tumor Analysis group's simple rules (SR) for interpretation of TVS with subjective assessment (SA) by an experienced ultrasound operator when TVS results are inconclusive (referred to hereafter as SR ± SA), (2) SR ± SA and cancer antigen 125 (CA 125), (3) SR ± SA and human epididymis protein 4 (HE4) and (4) SR ± SA and the risk of malignancy algorithm (ROMA). Our main hypothesis was that the addition of the biomarkers to SR ± SA could improve triaging of these patients in terms of diagnostic accuracy (i.e. malignant vs benign). As secondary analyses, we estimated the cost effectiveness of the four strategies and the diagnostic accuracy of SR ± SA at the study hospitals. METHODS: Between February 2013 and January 2015, 447 consecutive patients who were scheduled for surgery for an adnexal mass at the S. Anna and Mauriziano Hospitals in Turin were enrolled in this multicenter prospective cohort study. Preoperative TVS was performed and preoperative CA 125 and HE4 levels were measured. Pathology reports were used to assess the diagnostic accuracy of the four triage strategies and the cost of each strategy was calculated. RESULTS: A total of 391 patients were included in the analysis: 57% (n = 221) were premenopausal and 43% (n = 170) were postmenopausal. The overall prevalence of malignancy was 21%. SR were conclusive in 89% of patients and thus did not require SA; the overall performance of SR ± SA showed a sensitivity of 82%, specificity of 92% and positive and negative predictive values and positive and negative likelihood ratios of 74%, 95%, 10.5 and 0.19, respectively. In premenopausal women, mean cost among the four triage strategies varied from €36.41 for SR ± SA to €70.12 for SR ± SA + ROMA. The addition of biomarkers to SR ± SA showed no diagnostic advantage compared with SR ± SA alone and was more costly. Among postmenopausal women, mean cost among the four triage strategies varied from €39.52 for SR ± SA to €73.23 for SR ± SA + ROMA. Among these women, SR ± SA + CA 125 and SR ± SA + ROMA had a higher sensitivity (both 92% (95% CI, 85-99%)) than SR ± SA (81% (95% CI, 71-91%)), but SR ± SA had a higher specificity (84% (95% CI, 77-91%)). SR ± SA + CA 125 and SR ± SA + ROMA improved diagnostic accuracy, each diagnosing a third more malignant adnexal masses. In postmenopausal women, compared with SR ± SA alone, SR ± SA + CA 125 showed a net reclassification improvement (NRI) of 28.8% at an extra cost of €13.00, while the extra cost for SR ± SA + ROMA was €33.71, with a comparable gain, in terms of NRI, as that of SR ± SA + CA 125. CONCLUSIONS: In our study sample, SR ± SA seems to be the best strategy to triage women with adnexal masses for surgical management. Among postmenopausal women, SR ± SA + CA 125 increased the NRI at a reasonable extra cost. Our data do not justify the use of HE4 and ROMA in the initial triage of women with adnexal masses. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.


Asunto(s)
Enfermedades de los Anexos/diagnóstico , Triaje , Enfermedades de los Anexos/diagnóstico por imagen , Enfermedades de los Anexos/economía , Enfermedades de los Anexos/epidemiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/sangre , Antígeno Ca-125/sangre , Estudios de Cohortes , Análisis Costo-Beneficio , Femenino , Humanos , Italia/epidemiología , Persona de Mediana Edad , Programas Nacionales de Salud , Estudios Prospectivos , Proteínas/metabolismo , Sensibilidad y Especificidad , Proteína 2 de Dominio del Núcleo de Cuatro Disulfuros WAP , Adulto Joven
3.
Eur J Gynaecol Oncol ; 36(4): 383-8, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26390687

RESUMEN

OBJECTIVE: To evaluate the outcome of vaginal intraepithelial neoplasia (VaIN) treatment with CO2 laser vaporization in terms of local recurrence and progression to vaginal carcinoma. Additionally, the authors investigated the predictive factors for first recurrence. MATERIALS AND METHODS: The medical records of all patients treated for VaIN with CO2 laser vaporization at Sant'Anna Hospital in Turin (1995-2012), were retrospectively reviewed. A univariate logistic model was applied to evaluate selected clinical features as predictive factors for recurrence. A multivariate logistic regression analysis was then carried out including significant risk factors after univariate analysis (p < 0.05). RESULTS: The analysis included 285 out of 302 patients. Seventy-one (25%) women relapsed; of these 24 VaIN 1 (22%), 37 VaIN 2 (27%), and ten VaIN 3 (26%). The median time to the first recurrence was 5.2 months (1.4-127.8) for VaIN 1, 6.6 months (1-85.2) for VaIN 2, and 3.6 months (1.2-62) for VaIN 3. Sixty-one out of 71 patients were retreated with CO2 laser vaporization. At the last follow-up visit, 273 (96%) women were free from VaIN. No patients progressed to vaginal carcinoma. The multivariate model showed a higher risk of VaIN recurrence in the case of previous hysterectomy (HR 3.3, 95% CI 1.7-6.3, p < 0.001) and concomitant H-SIL on the Pap smear (HR 1.9, 95% CI 1.2-3.1, p = 0.008). CONCLUSION: CO2 laser vaporization is an effective low impact treatment for VaIN. Despite this, VaIN recur, in particular in cases of previous hysterectomy and concomitant H-SIL on the Pap smear. An intensive follow-up is proposed for women with a high risk of VaIN relapse.


Asunto(s)
Carcinoma in Situ/cirugía , Láseres de Gas/uso terapéutico , Recurrencia Local de Neoplasia/etiología , Neoplasias Vaginales/cirugía , Adolescente , Adulto , Anciano , Femenino , Humanos , Modelos Logísticos , Persona de Mediana Edad , Estudios Retrospectivos , Volatilización
4.
Gynecol Oncol ; 132(3): 611-7, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24342439

RESUMEN

PURPOSE: Neoadjuvant chemotherapy [NACT] followed by radical hysterectomy is an alternative therapeutic option to concurrent chemotherapy-radiotherapy for locally advanced cervical cancer. However there are very few data about the effectiveness of any post-operative treatment in this clinical setting. The purpose of this study was to correlate the patterns of recurrence and the clinical outcomes of cervical cancer patients who received NACT, with postoperative adjuvant treatment. PATIENTS AND METHODS: This retrospective multicenter study included 333 patients with FIGO stage Ib2-IIb cervical cancer who underwent platinum-based NACT followed by radical surgery. Pathological responses were retrospectively assessed as complete; optimal partial; and suboptimal response. Overall optimal response rate was the sum of complete and optimal partial response rates. RESULTS: On the whole series, recurrence-free survival was significantly longer in patients who achieved an overall optimal response than in those who did not (p<0.0001), and in patients who received adjuvant chemotherapy compared to those who did not (p=0.0001). On multivariate analysis, consolidation therapy (p=0.0012) was the only independent prognostic variable for recurrence-free survival; whereas FIGO stage (p=0.0169) and consolidation therapy (p=0.0016) were independent prognostic variables for overall survival. CONCLUSION: Optimal responders after chemo-surgical treatment for FIGO stage Ib2-IIb cervical cancer do not need any further treatment. Additional cycles of chemotherapy could be of benefit for patients with suboptimal response and intra-cervical residual disease. Both adjuvant chemotherapy and adjuvant radiation treatments do not seem to improve the clinical outcome of patients with extra-cervical residual disease compared to no further treatment.


Asunto(s)
Neoplasias del Cuello Uterino/terapia , Adenocarcinoma/patología , Adenocarcinoma/terapia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Braquiterapia , Carcinoma Adenoescamoso/patología , Carcinoma Adenoescamoso/terapia , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/terapia , Quimioradioterapia , Quimioterapia Adyuvante , Cisplatino/administración & dosificación , Supervivencia sin Enfermedad , Femenino , Humanos , Histerectomía , Escisión del Ganglio Linfático , Persona de Mediana Edad , Terapia Neoadyuvante , Recurrencia Local de Neoplasia/patología , Estadificación de Neoplasias , Cuidados Posoperatorios/métodos , Hemorragia Posoperatoria , Estudios Retrospectivos , Neoplasias del Cuello Uterino/patología
5.
Mar Pollut Bull ; 59(4-7): 175-81, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19560169

RESUMEN

The (210)Pb dating method was first introduced by Goldberg (1963), and since then has been applied to study sediment from lakes, estuaries and coastal marine environments. Hundreds of studies around the world have used (210)Pb as a geochronological tool in aquatic ecosystems. However little attention has been paid to the potential of this naturally occurring isotope as an environmental tracer of ecological events. Here we report three instances in which (210)Pb profiles measured on undisturbed sediment cores from lakes, rivers and fjords show us the potential of (210)Pb profile as a tracer of natural and anthropogenic processes. The methodology used here is a suite of techniques combining biogeochemistry (micro-electrodes), paleomagnetism (susceptibility), sediment characteristics (LOI) and visualization (SPI and X-ray) applied to the interpretation of (210)Pb profiles. We measured (210)Pb profiles on sediments from a river, Cruces River (Chile), which recorded a clear shift in the water chemistry caused by a pulp mill effluent to the river. Here metal mobilization and remobilization of the tracer may be the cause of the observed profile. We also measured (210)Pb profiles in sediment from two fjords of Southern Chile (Pillan and Reñihue), the sudden deposition change of fresh (210)Pb with depth observed could very well be the result of bioturbation but it occurred in a seafloor area deprived of bioturbators. In this case, (210)Pb recorded the onset of aquaculture activities (fish farming) that took place two decades ago. Finally, (210)Pb profiles measured in two lakes in the "pampa Argentina": Epecuen and Venado showed a particular shape with depth. These profiles apparently registered a sudden depositional event with recent (210)Pb material, probably related to strong shifts in precipitation and drought cycles in that part of the world. These three examples show that (210)Pb profiles provide valuable information not only on geochronology, but also related to natural and anthropogenic short term processes, as shown here, but these are not always reported and well understood.


Asunto(s)
Ecosistema , Monitoreo del Ambiente , Sedimentos Geológicos/química , Radioisótopos de Plomo/análisis , Ríos/química , Contaminantes Químicos del Agua/análisis
6.
Gynecol Oncol ; 107(1 Suppl 1): S150-4, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17868785

RESUMEN

OBJECTIVE: The aim of this study was to evaluate how much clinical surveillance performed by follow-up scheduled appointments may correctly identify asymptomatic recurrences and describe the pattern of relapse detected by procedures. METHODS: The records of 327 consecutive women with recurrent cervical cancer treated from 1980 to 2005 were retrospectively collected in 8 Italian Institutions. Primary disease and recurrence data were picked up: diagnosis, type of treatment, FIGO stage, tumour grade, histology, clinical lesion size, number of localizations and site of relapse, presence of symptoms and primary method of detection, the type of treatment of recurrence and follow-up data, such as appointment date, clinical status and procedure performed. A multivariate analysis was carried out using the Cox proportional hazards regression model. Survival curves were calculated using the Kaplan-Meier technique. Survival differences were evaluated by the log-rank test. RESULTS: Sixty-seven out of 327 patients (20.5%) had a local recurrence on vaginal vault, 120 (36.7%) in central pelvis, 31 (9.5%) in pelvic wall, 16 cases (4.9%) in lymph nodes. Seventy-nine patients (24.2%) showed a distant relapse while 14 (4.3%) developed both a distant and local relapse. Among patients with distant relapses 39 (49.4%) had lung metastasis, 41 (51.9%) an hepatic recurrence, 4 (5.1%) a bone relapse. Among distant sites 32 out of 79 patients (40.5%) had single relapse and 46 (58.2%) had multiple localizations. The site of relapse influenced survival since patients with vaginal vault recurrences lived significantly longer than patients with recurrences in other sites. Ninety-seven (29.7%) patients were symptomatic and anticipated the scheduled visit, 66 (20.2%) reported their symptoms during the follow-up visit and 164 (50.1%) were asymptomatic and the diagnostic path was introduced by a planned visit or exam. Between asymptomatic patients the first procedure was clinical visit for 85 patients out of 164 patients (51.8%), imaging for 60 patients (36.6%), both clinical visit and imaging for 14 (8.5%) and cytology for 5 (3%, Pap smear test). The median OS of symptomatic patients was 37 months versus 109 months of asymptomatic patients (Log rank, p=0.00001). The median survival since recurrence was 9 months for symptomatic patients and median was not reached for asymptomatic patients (p<0.0001). The median disease-free interval was 24 months for asymptomatic patients vs. 36 months for symptomatic patients (p=0.03). CONCLUSIONS: Our study helps demonstrate the great need of prospective cost-effectiveness studies which are lacking at the present time.


Asunto(s)
Recurrencia Local de Neoplasia/diagnóstico , Neoplasias del Cuello Uterino/diagnóstico , Femenino , Estudios de Seguimiento , Humanos , Análisis Multivariante , Recurrencia Local de Neoplasia/patología , Prueba de Papanicolaou , Modelos de Riesgos Proporcionales , Recurrencia , Estudios Retrospectivos , Neoplasias del Cuello Uterino/patología , Frotis Vaginal
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