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1.
Sci Rep ; 14(1): 10793, 2024 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-38734754

RESUMEN

Iron oxide-copper-gold (IOCG) deposits are a vital source of copper and critical elements for emerging clean technologies. Andean-type IOCG deposits form in continental arcs undergoing extension, and they have a temporal relationship with magmatism although they do not exhibit a close spatial relation with the causative intrusions. The processes required to form IOCG deposits and their potential connections to iron oxide-apatite (IOA)-type mineralization remain poorly constrained, as well as the characteristics of magmatism linked to both deposit types. Here we combine zircon U-Pb geochronology with zircon trace element geochemistry of intrusive rocks associated with the Candelaria deposit, one of the world's largest IOCG deposits, to unravel distinctive signatures diagnostic of magmatic fertility. Our results reveal a marked transition in the geochemistry of intrusions in the Candelaria district, characterized by changes in the redox state, water content and temperature of magmas over time. The oldest magmatic stage (~ 128-125 Ma), prior to the formation of the Candelaria deposit, was characterized by zircon Eu/Eu* ratios of 0.20-0.42, and redox conditions of ΔFMQ - 0.4 to + 1.0. The earliest magmatic stage related to the formation of Fe-rich mineralization at Candelaria (118-115 Ma) exhibits low zircon Eu/Eu* ratios (0.09-0.18), low oxygen fugacity values (ΔFMQ ~- 1.8 to + 0.2) and relatively high crystallization temperatures. In contrast, the youngest stage at ~ 111-108 Ma shows higher zircon Eu/Eu* (~ 0.37-0.69), higher oxygen fugacity values (ΔFMQ ~ + 0.4 to + 1.3) and a decrease in crystallization temperatures, conditions that are favorable for the transport and precipitation of sulfur and chalcophile elements. We conclude that Candelaria was formed through two distinct ore-forming stages: the first associated with a reduced, high temperature, water-poor magma developed under a low tectonic stress, followed by a more oxidized, water-rich, and low temperature magmatic event related to a compressional regime. The first event led to Fe-rich and S-poor IOA-type mineralization, while the second event with geochemical signatures similar to those of porphyry copper systems, generated the Cu- and S-rich mineralization. This late stage overprinted preexisting IOA mineralization resulting in the formation of the giant Candelaria IOCG deposit.

2.
Drugs Today (Barc) ; 56(10): 669-688, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33185631

RESUMEN

Trabectedin is a marine-derivate antitumor drug with a relevant cytotoxic activity and good safety profile. It has been investigated for the treatment of solid diseases, including ovarian cancer (OC), breast cancer, and soft-tissue sarcoma. In 2009, results from the pivotal trial OVA-301 led the European Medicines Agency (EMA) to the approval of trabectedin in combination with PEGylated liposomal doxorubicin for the treatment of platinum-sensitive recurrent OC; further studies revealed an additional benefit also in the subgroup of patients with partially platinum-sensitive disease and in those with a BRCA-mutated status. Additionally, trabectedin demonstrated to prolong the time interval to the subsequent chemotherapy line. Recently, the improved understanding of the antitumor action exerted by trabectedin paved the way to new investigational trials exploring its combination with targeted therapies.


Asunto(s)
Neoplasias Ováricas , Tetrahidroisoquinolinas , Protocolos de Quimioterapia Combinada Antineoplásica , Ensayos Clínicos como Asunto , Dioxoles/efectos adversos , Femenino , Humanos , Recurrencia Local de Neoplasia/tratamiento farmacológico , Neoplasias Ováricas/tratamiento farmacológico , Tetrahidroisoquinolinas/efectos adversos , Trabectedina
3.
Anaesthesia ; 75(7): 928-934, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32246838

RESUMEN

The first person-to-person transmission of the 2019 novel coronavirus in Italy on 21 February 2020 led to an infection chain that represents one of the largest known COVID-19 outbreaks outside Asia. In northern Italy in particular, we rapidly experienced a critical care crisis due to a shortage of intensive care beds, as we expected according to data reported in China. Based on our experience of managing this surge, we produced this review to support other healthcare services in preparedness and training of hospitals during the current coronavirus outbreak. We had a dedicated task force that identified a response plan, which included: (1) establishment of dedicated, cohorted intensive care units for COVID-19-positive patients; (2) design of appropriate procedures for pre-triage, diagnosis and isolation of suspected and confirmed cases; and (3) training of all staff to work in the dedicated intensive care unit, in personal protective equipment usage and patient management. Hospital multidisciplinary and departmental collaboration was needed to work on all principles of surge capacity, including: space definition; supplies provision; staff recruitment; and ad hoc training. Dedicated protocols were applied where full isolation of spaces, staff and patients was implemented. Opening the unit and the whole hospital emergency process required the multidisciplinary, multi-level involvement of healthcare providers and hospital managers all working towards a common goal: patient care and hospital safety. Hospitals should be prepared to face severe disruptions to their routine and it is very likely that protocols and procedures might require re-discussion and updating on a daily basis.


Asunto(s)
Infecciones por Coronavirus/terapia , Servicio de Urgencia en Hospital , Neumonía Viral/terapia , Derivación y Consulta , Capacidad de Reacción/estadística & datos numéricos , Centros de Atención Terciaria , Betacoronavirus , COVID-19 , Brotes de Enfermedades , Humanos , Italia , Pandemias , SARS-CoV-2
4.
Drugs Today (Barc) ; 55(8): 503-512, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31461087

RESUMEN

Uterine leiomyomas represent the most common form of benign gynecological tumors affecting 20-40% of women during their life. Several therapeutic options are available for treating these patients. The use of medical treatment for myomas has largely grown in the last years, in particular for women who would refuse, postpone or are not candidates for surgery. In the last years, the clinical investigation of gonadotropin-releasing hormone (GnRH) antagonists (GnRH-ants) has emerged. This class of drugs exerts pure competitive antagonistic activity on the GnRH receptor at the pituitary gland, producing an immediate stop in the release of gonadotropins and sex steroids. Relugolix is an orally active nonpeptide GnRH-ant, recently licensed for marketing in Japan for the treatment of symptoms related to uterine myomas. Currently, several phase III clinical trials are ongoing to evaluate this molecule in this setting in the U.S. and Europe.


Asunto(s)
Leiomioma/tratamiento farmacológico , Compuestos de Fenilurea/uso terapéutico , Pirimidinonas/uso terapéutico , Neoplasias Uterinas/tratamiento farmacológico , Femenino , Humanos
5.
Drugs Today (Barc) ; 55(6): 377-384, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31250842

RESUMEN

Glaucoma is a main cause of irreversible vision impairment and its prevalence is expected to rise significantly in the near future. Among the current medications, prostaglandin analogues (PGAs) are widely used and considered as a first-line strategy in the management of glaucoma and ocular hypertension (OHT). However, given the non-negligible incidence of adverse ocular effects (conjunctival hyperemia, increase of iris pigmentation and eyelash changes) due to the use of this class of drugs, novel PGAs are being investigated. Omidenepag isopropyl is a selective prostaglandin EP2 receptor agonist which was approved on September 21, 2018, in Japan for the treatment of glaucoma and OHT. In this review, we will discuss its pharmacokinetics, pharmacodynamics and clinical efficacy, focusing also on its safety and tolerability profile.


Asunto(s)
Antihipertensivos/uso terapéutico , Glaucoma/tratamiento farmacológico , Glicina/análogos & derivados , Hipertensión Ocular/tratamiento farmacológico , Pirazoles/uso terapéutico , Piridinas/uso terapéutico , Glicina/uso terapéutico , Humanos , Japón , Resultado del Tratamiento
6.
Drugs Today (Barc) ; 55(4): 237-246, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31050692

RESUMEN

First-line medical therapies for treating pain associated with endometriosis mainly consist in combined oral contraceptives and progestins. However, some women, having persistence of symptoms, may require further therapeutic options. Among these, gonadotropin-releasing hormone (GnRH) agonists (GnRH-as) have been widely employed in the last 30 years, despite being characterized by an unfavorable safety profile. Currently, new alternative investigational options are being investigated to treat this benign chronic disease. GnRH antagonists (GnRH-ants) are innovative hormonal drugs that do not induce flare-up effects and present also a limited onset of hypoestrogenic symptoms; in fact, their pharmacological mechanism of action, which consists in pure antagonistic activity, differs from that of traditional GnRH-as. In July 2018, the U.S. Food and Drug Administration (FDA) approved elagolix sodium for the management of moderate to severe pain associated with endometriosis, after the drug showed promising efficacy and safety results in previous phase III trials. This monograph aims to provide a complete overview of the pharmacokinetics, clinical efficacy and safety of this GnRH-ant for treat¬ing patients with endometriosis.


Asunto(s)
Endometriosis/tratamiento farmacológico , Antagonistas de Hormonas/uso terapéutico , Hidrocarburos Fluorados/uso terapéutico , Dolor/tratamiento farmacológico , Pirimidinas/uso terapéutico , Femenino , Humanos
7.
Ultrasound Obstet Gynecol ; 53(3): 402-409, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30079504

RESUMEN

OBJECTIVES: The primary aim of this study was to compare the diagnostic accuracy of transvaginal sonography (TVS) with vs without bowel preparation (BP) in detecting the presence of rectosigmoid endometriosis. Secondary objectives were to compare the diagnostic accuracy of the two techniques in estimating infiltration of the submucosa, length of the largest rectosigmoid nodules, distance of the nodules from the anal verge and presence of multifocal disease. METHODS: This was a prospective study of patients with symptoms of pelvic pain for more than 6 months and/or suspicion of endometriosis referred to our institution between October 2016 and April 2018. Participants underwent a first TVS without BP followed by TVS with BP within a time interval of 1 week to 3 months. The examinations were performed independently and blindly by two sonographers. Only patients who underwent laparoscopy within the 6 months following the second ultrasound examination were included. Ultrasound results using the two techniques were compared with surgical and histological findings. RESULTS: Of the 262 patients included in the study, 118 had rectosigmoid endometriosis confirmed at surgery. There was no significant difference in accuracy between TVS with and that without BP in diagnosing the presence of rectosigmoid endometriosis (93.5% vs 92.3%; P = 0.453). No significant difference was observed in accuracy between TVS with and that without BP in diagnosing submucosal infiltration (88.8% vs 84.6%; P = 0.238) and multifocal disease (97.2% vs 95.2%; P = 0.727) in patients diagnosed sonographically with rectosigmoid endometriosis. The accuracy of TVS with BP was similar to that of TVS without BP in estimating the maximum diameter of the largest nodule (P = 0.644) and the distance between the more caudal rectosigmoid nodule and the anal verge (P = 0.162). CONCLUSION: BP does not improve the diagnostic performance of TVS in detecting rectosigmoid endometriosis and in assessing characteristics of endometriotic nodules. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.


Asunto(s)
Colon Sigmoide/diagnóstico por imagen , Endometriosis/diagnóstico por imagen , Recto/diagnóstico por imagen , Ultrasonografía/métodos , Vagina/diagnóstico por imagen , Adulto , Catárticos/administración & dosificación , Colon Sigmoide/patología , Endometriosis/patología , Endometriosis/cirugía , Femenino , Humanos , Laparoscopía/métodos , Laparoscopía/estadística & datos numéricos , Dolor Pélvico/diagnóstico , Dolor Pélvico/etiología , Embarazo , Estudios Prospectivos , Recto/patología , Sensibilidad y Especificidad , Ultrasonografía/tendencias , Vagina/patología
8.
Eur J Obstet Gynecol Reprod Biol ; 222: 89-94, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29408753

RESUMEN

INTRODUCTION: This patient preference prospective study was designed to compare patients' satisfaction in women with endometriosis treated either by an extended-cycle oral contraception (OC) or by norethindrone acetate (NETA). METHODS: This patient preference prospective study included women of reproductive age with endometriosis. Patients were submitted to one of the following 12 months' treatments: Group A, continuous oral treatment with NETA (2.5 mg/day) and Group B, a 91-day extended-cycle OC (LNG/EE 150/30 mcg for 84 days and EE 10 mcg for 7 days). Patient satisfaction was the primary endpoint. RESULTS: There was no statistically significant difference in the rate of satisfied patients at 12-month follow up between the two study groups, 82.2% and 68.4% in Group A and Group B respectively (p = 0.143). At 6 and 12-months, there was a significant amelioration in the intensity of all pain in both groups. The median number of days of unscheduled bleeding during the first cycle was significantly higher in Group B compared to Group A. CONCLUSION: Both NETA and extended-cycle OC are effective in treating pain symptoms related to endometriosis. Extended-cycle OC may cause more unscheduled bleeding, but the rate of satisfaction for those who completed the treatment was similar in the two groups.


Asunto(s)
Anticonceptivos Sintéticos Orales/uso terapéutico , Endometriosis/tratamiento farmacológico , Enfermedades Intestinales/tratamiento farmacológico , Noretindrona/análogos & derivados , Enfermedades del Ovario/tratamiento farmacológico , Prioridad del Paciente , Enfermedades Vaginales/tratamiento farmacológico , Adulto , Anticonceptivos Sintéticos Orales/efectos adversos , Combinación de Medicamentos , Endometriosis/fisiopatología , Etinilestradiol/efectos adversos , Etinilestradiol/uso terapéutico , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Análisis de Intención de Tratar , Enfermedades Intestinales/fisiopatología , Italia/epidemiología , Levonorgestrel/efectos adversos , Levonorgestrel/uso terapéutico , Metrorragia/epidemiología , Metrorragia/etiología , Metrorragia/prevención & control , Noretindrona/efectos adversos , Noretindrona/uso terapéutico , Acetato de Noretindrona , Enfermedades del Ovario/fisiopatología , Dimensión del Dolor , Pacientes Desistentes del Tratamiento , Dolor Pélvico/epidemiología , Dolor Pélvico/etiología , Dolor Pélvico/prevención & control , Estudios Prospectivos , Enfermedades Vaginales/fisiopatología
9.
Ultrasound Obstet Gynecol ; 52(5): 666-671, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-29266553

RESUMEN

OBJECTIVES: Several studies have investigated the correlation between endometriosis and adverse pregnancy and perinatal outcomes. However, the role of adenomyosis as a risk factor for adverse perinatal outcome in women with endometriosis has yet to be established. The aim of this study was to explore if fetal and maternal outcomes, in particular the incidence of a small-for-gestational-age (SGA) infant, are different in pregnant women with endometriosis only from in those with the concomitant presence of diffuse or focal adenomyosis. METHODS: This was a retrospective analysis of data collected prospectively during a 3-year period. We included 206 pregnant women with endometriosis: 148 (71.8%) with endometriosis only, 38 (18.4%) with focal adenomyosis and 20 (9.7%) with diffuse adenomyosis. Adenomyosis was diagnosed using ultrasonography and was classified as focal or diffuse. The study included patients who conceived spontaneously or by an assisted reproductive technique. Demographics, ultrasound variables and outcome were compared between women with endometriosis only and those with diffuse and those with focal adenomyosis. Logistic regression analysis was performed to assess the association of variables with SGA at birth in women with diffuse and those with focal adenomyosis. RESULTS: The three groups were similar in demographic characteristics (age, body mass index, mode of conception). Patients with diffuse adenomyosis compared with those with endometriosis only had significantly lower pregnancy-associated plasma protein A (0.61 vs 0.88 multiple of the median, P < 0.001), higher mean uterine artery pulsatility index in the first (2.23 vs 1.67, P < 0.001) and second (1.30 vs 0.94, P < 0.001) trimesters of pregnancy, and higher incidence of SGA (40% vs 10.8%, P < 0.001). No statistically significant differences were found in patients with focal adenomyosis compared with those with endometriosis only. Logistic regression analysis demonstrated that diffuse adenomyosis (odds ratio = 3.744; 95% CI, 1.158-12.099; P = 0.027) was the only independent risk factor for SGA. CONCLUSIONS: The presence of diffuse adenomyosis in pregnant women with endometriosis is strongly associated with delivery of a SGA infant. Women with diffuse adenomyosis should be treated as being at high risk of placental dysfunction, and these pregnancies might therefore need closer monitoring. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.


Asunto(s)
Adenomiosis/diagnóstico por imagen , Endometriosis/diagnóstico por imagen , Retardo del Crecimiento Fetal/epidemiología , Recién Nacido Pequeño para la Edad Gestacional , Ultrasonografía Prenatal , Adulto , Femenino , Humanos , Incidencia , Recién Nacido , Italia/epidemiología , Embarazo , Resultado del Embarazo , Estudios Prospectivos , Estudios Retrospectivos , Factores de Riesgo
10.
Cell Prolif ; 49(4): 523-38, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27389299

RESUMEN

OBJECTIVES: In spite of high sensitivity of A549 cells (p53(+/+) ) to lethal effects of photodynamic therapy with 5-aminolaevulinic acid (5-ALA/PDT), DNA damage was observed only in H1299 cells (p53(-/-) ), suggesting that p53 may exert a protective effect. Studies on human colon adenocarcinoma cell lines HCT-116, and their cognate knockouts for p53, were not entirely consistent with the assumption above. Exploring alternative explanations for such conflicting behaviour, we observed that expression of the ATP-binding cassette G2 (ABCG2), a regulator of cell component efflux, had important effects on PDT-generated DNA injury in PC3 cells (prostate) which are p53(-/-) and positive for ABCG2. Addition of an ABCG2 inhibitor in ABCG2 positive A549 (p53(+/+) ) and PC3 (p53(-/-) ) cells eliminated resistance to DNA damage. MATERIALS AND METHODS: All cell lines investigated were incubated with 5-ALA and irradiated. Effects of PDT were evaluated assessing residual cell viability, cell-cycle profiles, PpIX localization, comet assay and Western blotting. Identical measurements were made in the presence of ABCG2 inhibitor, in cells expressing the transporter. RESULTS: Our data show that cell aptitude to defend its DNA from PDT-induced injury was mainly ruled by ABCG2 expression. These findings, while providing helpful information in predicting effectiveness of 5-ALA/PDT, may indicate a way to shift PDT from a palliative to a more effective approach in anti-cancer therapy.


Asunto(s)
Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2/metabolismo , Ácido Aminolevulínico/farmacología , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Neoplasias Colorrectales/tratamiento farmacológico , Daño del ADN/efectos de los fármacos , Neoplasias Pulmonares/tratamiento farmacológico , Proteínas de Neoplasias/metabolismo , Fármacos Fotosensibilizantes/farmacología , Proteína p53 Supresora de Tumor/metabolismo , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2/genética , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/patología , Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Colon/efectos de los fármacos , Colon/metabolismo , Colon/patología , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/metabolismo , Neoplasias Colorrectales/patología , Humanos , Pulmón/efectos de los fármacos , Pulmón/metabolismo , Pulmón/patología , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Proteínas de Neoplasias/genética , Fotoquimioterapia , Recto/efectos de los fármacos , Recto/metabolismo , Recto/patología , Proteína p53 Supresora de Tumor/genética
11.
Anat Sci Int ; 90(4): 240-50, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25316088

RESUMEN

The Purkinje network is not macroscopically visible in human hearts. Sunao Tawara found himself in trouble in the early 1900s, when studying the human heart network. He gained a much better understanding of the net after starting to work with ungulates' hearts. The ungulate heart is proposed as an auxiliary didactic model for the study of the human conduction system. This work provides a detailed description of the India ink injection technique to allow a naked eye visualization of the Purkinje network. The heart muscle was made diaphanous for direct visualization of the ungulate heart intramyocardial network, and computer tomography was employed for visualization of the three dimensional structure of the whole network. The intramyocardial network in the interventricular septum was identified. The pattern of the Purkinje network is described as a connected noneulerian graph, and its possible implications on the mechanism of arrhythmias is discussed. The main differences between the ungulate and human heart conduction systems are stressed.


Asunto(s)
Anatomía/métodos , Carbono , Sistema de Conducción Cardíaco/anatomía & histología , Sistema de Conducción Cardíaco/diagnóstico por imagen , Ramos Subendocárdicos/anatomía & histología , Ramos Subendocárdicos/diagnóstico por imagen , Animales , Arritmias Cardíacas/etiología , Bovinos , Humanos , Imagenología Tridimensional , Modelos Anatómicos , Tomografía , Tomografía Computarizada por Rayos X
13.
Dentomaxillofac Radiol ; 41(5): 396-404, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22241874

RESUMEN

OBJECTIVES: The aim of the study was to verify the concordance of contrast-enhanced CT (CECT) and MRI evaluation among four radiologists in detecting metastatic cervical lymph nodes of oral cancer patients. METHODS: Ten patients underwent clinical and imaging examinations (CECT and MRI). Four radiologists, two oral and maxillofacial radiologists (OMRs) and two medical radiologists (MRs), independently analysed the images twice. Cohen's kappa index and Wilcoxon signed-rank test were used to verify the concordance between all analyses. RESULTS: Regarding the interobserver agreement, the OMRs presented excellent kappa values for determining the regional lymph nodes (N-stage) in both CECT and MRI. The MRs presented moderate agreement for CECT evaluation at the first reading, but no concordance was found for the other analyses. When each imaging modality was analysed separately, kappa values were higher between all examiners. Greater variability was demonstrated between N-stage evaluation using different examinations. All radiologists were able to identify a greater number of metastatic lymph nodes in CECT than in MRI, except one MR, but no significant difference was found for all readers. The differences between the number of metastatic lymph nodes among all radiologists were not statistically significant. Moderate intraobserver agreement was observed for CECT and MRI evaluation, except for one MR. CONCLUSIONS: The differences found between the N-stage performed by OMRs and MRs support the necessity of a multidisciplinary approach in the imaging evaluation of metastatic nodes. Further studies are necessary to confirm which imaging modality should be employed when evaluating neck areas.


Asunto(s)
Carcinoma de Células Escamosas/secundario , Neoplasias de Cabeza y Cuello/secundario , Metástasis Linfática/patología , Imagen por Resonancia Magnética , Neoplasias de la Boca/patología , Cuello/patología , Tomografía Computarizada por Rayos X , Adulto , Anciano , Carcinoma de Células Escamosas/diagnóstico por imagen , Medios de Contraste , Diagnóstico Diferencial , Femenino , Neoplasias de Cabeza y Cuello/diagnóstico por imagen , Humanos , Yopamidol , Metástasis Linfática/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Neoplasias de la Boca/diagnóstico por imagen , Estadificación de Neoplasias , Estadísticas no Paramétricas
14.
Artículo en Inglés | MEDLINE | ID: mdl-21736550

RESUMEN

BACKGROUND AND PURPOSE: This study was designed to compare heterophoria measurements obtained using the methods: prisms cover test (prism alternate cover test), von Graefe technique, Maddox rod test and modified Thorington test. Given the different methodological features of these tests, our working hypothesis was that these tests would not be interchangeable and repeatability would vary. METHODS: Horizontal deviation measurements were made at: far distance (six meters) and near distance (40 centimeters) on two occasions in 61 young subjects of mean age 19.7 years (range 18 -32 years), with essentially normal eyes and vision, who were not familiar with the methods used. Statistical repeatability and agreement were determined using the Bland and Altman method. RESULTS: Repeatability: No difference between the results of the various heterophoria tests was statistically significant. Coefficients of repeatability were always best when the tests were conducted at far, the cover test being the most repeatable. Agreement: Mean differences between absolute values ranged from 1.7 prism diopters to 5.1 prism diopters for measurements at far and from 2.1 prism diopters to 3.4 prism diopters at near. CONCLUSIONS: The alternating prism cover test was the most repeatable test for measuring latent horizontal deviations. Among the subjective tests, the modified Thorington test was the most repeatable. The low level of agreement observed between the different tests makes their interchangeable use in clinical practice not recommended.


Asunto(s)
Ojo , Estrabismo , Cabeza , Humanos
15.
AJNR Am J Neuroradiol ; 31(1): 88-90, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19696137

RESUMEN

Lipoid proteinosis is a rare genodermatosis characterized by multisystem involvement due to intracellular deposition of an amorphous hyaline material. Lipoid proteinosis is caused by mutations in the ECM1 gene. In many patients, skin and mucosa abnormalities are the first manifestation. When the CNS is affected, a wide variety of neurologic abnormalities may be present. The hallmark findings are calcifications, mostly occurring in the amygdalae, hippocampus, parahippocampal gyrus, or even the striatum. Present in half of the patients, moniliform blepharosis is considered a pathognomonic finding. In the other half of patients imaging could assist in the diagnosis. The authors present a series of 3 cases of lipoid proteinosis with brief clinical data and imaging findings.


Asunto(s)
Amígdala del Cerebelo , Encefalopatías/etiología , Calcinosis/etiología , Cuerpo Estriado , Proteinosis Lipoidea de Urbach y Wiethe/complicaciones , Adolescente , Femenino , Humanos , Masculino , Persona de Mediana Edad
16.
Ophthalmic Physiol Opt ; 29(6): 606-14, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19663924

RESUMEN

PURPOSE: Clinical measurement of the accommodative response (AR) identifies the focusing plane of a subject with respect to the accommodative target. To establish whether a significant change in AR has occurred, it is important to determine the repeatability of this measurement. This study had two aims: First, to determine the intraexaminer repeatability of AR measurements using four clinical methods: Nott retinoscopy, monocular estimate method (MEM) retinoscopy, binocular crossed cylinder test (BCC) and near autorefractometry. Second, to study the level of agreement between AR measurements obtained with the different methods. METHODS: The AR of the right eye at one accommodative demand of 2.50 D (40 cm) was measured on two separate occasions in 61 visually normal subjects of mean age 19.7 years (range 18-32 years). The intraexaminer repeatability of the tests, and agreement between them, were estimated by the Bland-Altman method. We determined mean differences (MD) and the 95% limits of agreement [coefficient of repeatability (COR) and coefficient of agreement (COA)]. RESULTS: Nott retinoscopy and BCC offered the best repeatability, showing the lowest MD and narrowest 95% interval of agreement (Nott: -0.10 +/- 0.66 D, BCC: -0.05 +/- 0.75 D). The 95% limits of agreement for the four techniques were similar (COA = +/- 0.92 to +/-1.00 D) yet clinically significant, according to the expected values of the AR. The two dynamic retinoscopy techniques (Nott and MEM) had a better agreement (COA = +/-0.64 D) although this COA must be interpreted in the context of the low MEM repeatability (COR = +/-0.98 D). CONCLUSIONS: The best method of assessing AR was Nott retinoscopy. The BCC technique was also repeatable, and both are recommended as suitable methods for clinical use. Despite better agreement between MEM and Nott, agreement among the remaining methods was poor such that their interchangeable use in clinical practice is not recommended.


Asunto(s)
Acomodación Ocular/fisiología , Errores de Refracción/fisiopatología , Retinoscopía/métodos , Agudeza Visual/fisiología , Adulto , Femenino , Humanos , Masculino , Errores de Refracción/diagnóstico , Reproducibilidad de los Resultados , Adulto Joven
17.
Graefes Arch Clin Exp Ophthalmol ; 247(1): 121-7, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18791730

RESUMEN

BACKGROUND: Clinical measurement of the amplitude of accommodation (AA) provides an indication of maximum accommodative ability. To determine whether there has been a significant change in the AA, it is important to have a good idea of the repeatability of the measurement method used. The aim of the present study was to compare AA measurements made using three different subjective clinical methods: the push-up, push-down, and minus lens techniques. These methods differ in terms of the apparent size of the target, the end point used, or the components of the accommodation response stimulated. Our working hypothesis was that these methods are likely to show different degrees of repeatability such that they should not be used interchangeably. METHODS: The AA of the right eye was measured on two separate occasions in 61 visually normal subjects of mean age 19.7 years (range 18 to 32). The repeatability of the tests and agreement between them was estimated by the Bland and Altman method. We determined the mean difference (MD) and the 95% limits of agreement for the repeatability study (COR) and for the agreement study (COA). RESULTS: The COR for the push-up, push-down, and minus lens techniques were +/-4.76, +/-4.00, and +/-2.52D, respectively. Higher values of AA were obtained using the push-up procedure compared to the push-down and minus lens methods. The push-down method also yielded a larger mean AA than the negative-lens method. MD between the three methods were high in clinical terms, always over 1.75D, and the COA differed substantially by at least +/-4.50D. The highest agreement interval was observed when we compared AA measurements made using minus lenses and the push-up method (+/-5.65D). CONCLUSIONS: The minus lens method exhibited the best repeatability, least MD (-0.08D) and the smallest COR. Agreement between the three techniques was poor.


Asunto(s)
Acomodación Ocular , Técnicas de Diagnóstico Oftalmológico/normas , Optometría/métodos , Optometría/normas , Adolescente , Adulto , Técnicas de Diagnóstico Oftalmológico/estadística & datos numéricos , Humanos , Variaciones Dependientes del Observador , Optometría/estadística & datos numéricos , Reproducibilidad de los Resultados , Adulto Joven
18.
Ophthalmic Physiol Opt ; 28(5): 475-91, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18761485

RESUMEN

PURPOSE: This study was designed to determine the repeatability of fusional vergence ranges measured using the rotary prisms in the phoropter and in free space using the prism bar. The level of agreement between the two methods was also investigated. METHODS: In two separate sessions, negative and positive fusional vergence ranges (NFV and PFV, respectively) were measured at distance and near in 61 young adults (mean age 19.74, S.D. 2.5 years) who were unfamiliar with the methods used. Base-in and base-out blur, break and recovery points were sequentially determined. Both sets of measurements were obtained by the same examiner. At each distance, NFV was determined first and then PFV. The repeatability of the tests and agreement between measurements made with the phoropter rotary prisms and the prism bar were estimated by the Bland and Altman method. RESULTS: For both the phoropter rotary prisms and prism bar, NFV measurements showed better repeatability than PFV at both near and distance. Mean differences recorded for the NFV break and recovery points were non-significant (under 0.5Delta), while those observed for PFV were generally greater than 2Delta. When agreement between the two tests was assessed, it was found that break points were higher when determined using the phoropter rotary prisms, while recovery points were generally higher for the prism bar method. In clinical terms, according to the expected values of the NFV and PFV, agreement between the two techniques can be described as fair, because although mean differences were never greater than 5.5Delta, 95% agreement intervals were as wide as +/-8.00Delta for NFV and +/-13.19Delta for PFV. CONCLUSIONS: The two methods used to measure fusional vergences showed fairly good inter-session repeatability for measuring NFV but repeatability was reduced for PFV measurements. The level of agreement observed between the two methods was such that their interchangeable use in clinical practice is not recommended.


Asunto(s)
Acomodación Ocular/fisiología , Convergencia Ocular/fisiología , Trastornos de la Motilidad Ocular/fisiopatología , Pruebas de Visión/instrumentación , Adulto , Movimientos Oculares/fisiología , Femenino , Humanos , Masculino , Variaciones Dependientes del Observador , Reproducibilidad de los Resultados
19.
Binocul Vis Strabismus Q ; 22(2): 90-5, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17688417

RESUMEN

BACKGROUND AND PURPOSE: The purpose was to determine the efficacy of two types of contact lenses (spherical disposable and aplanatic) as treatment in a patient with esotropia with a high Accommodative Convergence/Accommodation Ratio (AC/A). Due to the possibility of the appearance of accommodative insufficiency in this kind of patient, (i.e., following many years of bifocal glasses use), the elimination of the plus addition lens is advisable. Nevertheless, in some patients, this change leads to the appearance of a residual angle of esodeviation in near vision. It was expected that monofocal aplanatic contact lenses could achieve, due to their optical characteristics, an accurate and orthotropic binocular alignment, without aggravating an undesirable manifestation of the accommodative insufficiency. METHODS: An experimental design of a single case (N=1) was used in which the subject acted as his own control. With bifocal glasses the subject displayed stability in his binocular and accommodative system at every distance of vision for the past three years. We compared the efficacy of two different types of hydrophilic contact lenses to control the angle of deviation, both at distance and at near vision. RESULTS: Neither of the two contact lenses produced the results of stability and the correct binocular alignment that had been achieved with bifocal glasses. This subject experienced a worse manifest esodeviation in distance vision with aplanatic lenses than with the disposable ones. CONCLUSIONS: These monofocal contact lenses did not create acceptable binocular alignment and stability in a subject with a high AC/A accommodative esotropia.


Asunto(s)
Acomodación Ocular , Lentes de Contacto , Convergencia Ocular , Esotropía/terapia , Niño , Humanos , Masculino , Visión Binocular , Agudeza Visual
20.
Phys Rev E Stat Nonlin Soft Matter Phys ; 65(1 Pt 2): 016205, 2002 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11800766

RESUMEN

We study the classical limit of quantum mechanics on graphs by introducing a Wigner function for graphs. The classical dynamics is compared to the quantum dynamics obtained from the propagator. In particular, we consider extended open graphs whose classical dynamics generate a diffusion process. The transport properties of the classical system are revealed in the scattering resonances and in the time evolution of the quantum system.

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