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1.
Nature ; 576(7786): 232-236, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31802002

RESUMEN

Remote observations of the solar photospheric light scattered by electrons (the K-corona) and dust (the F-corona or zodiacal light) have been made from the ground during eclipses1 and from space at distances as small as 0.3 astronomical units2-5 to the Sun. Previous observations6-8 of dust scattering have not confirmed the existence of the theoretically predicted dust-free zone near the Sun9-11. The transient nature of the corona has been well characterized for large events, but questions still remain (for example, about the initiation of the corona12 and the production of solar energetic particles13) and for small events even its structure is uncertain14. Here we report imaging of the solar corona15 during the first two perihelion passes (0.16-0.25 astronomical units) of the Parker Solar Probe spacecraft13, each lasting ten days. The view from these distances is qualitatively similar to the historical views from ground and space, but there are some notable differences. At short elongations, we observe a decrease in the intensity of the F-coronal intensity, which is suggestive of the long-sought dust free zone9-11. We also resolve the fine-scale plasma structure of very small eruptions, which are frequently ejected from the Sun. These take two forms: the frequently observed magnetic flux ropes12,16 and the predicted, but not yet observed, magnetic islands17,18 arising from the tearing-mode instability in the current sheet. Our observations of the coronal streamer evolution confirm the large-scale topology of the solar corona, but also reveal that, as recently predicted19, streamers are composed of yet smaller substreamers channelling continual density fluctuations at all visible scales.

2.
Prog Urol ; 33(6): 307-318, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37088584

RESUMEN

INTRODUCTION: Currently, bladder cancer detection is based on cytology and cystoscopy. White light cystoscopy (WLC) is an invasive procedure and may under-detect flat lesions. Blue light cystoscopy (BLC) and narrow band imaging (NBI) cystoscopy are new modalities that could improve the detection of non-muscle invasive bladder cancer (NMIBC) and its recurrence or progression to muscle invasive bladder cancer. We present a systematic review on BLC and NBI cystoscopy for bladder cancer diagnosis and NMIBC follow-up. MATERIAL AND METHODS: All available systematic reviews and meta-analyses on cystoscopy published in PubMed® between May 2010 and March 2021 were identified and reviewed. The main endpoints were clinical performance for bladder cancer diagnosis and for recurrence or progression detection during NMIBC follow-up, and additional value compared with cytology and/or WLC. RESULTS: Most of the meta-analyses and systematic reviews published suggest a better sensitivity of BLC and NBI cystoscopy compared to WLC, particularly for the detection of flat lesions (CIS). NBI- and BLC-guided TURBT could decrease the recurrence rates. However, their clinical utility to reduce progression rate and increase survival is still unclear. CONCLUSIONS: BLC and NBI cystoscopy are efficient techniques for bladder cancer diagnosis and NMIBC follow-up. However, their clinical benefit remains to be confirmed.


Asunto(s)
Cistoscopía , Neoplasias de la Vejiga Urinaria , Humanos , Cistectomía , Cistoscopía/métodos , Recurrencia Local de Neoplasia/diagnóstico por imagen , Recurrencia Local de Neoplasia/patología , Revisiones Sistemáticas como Asunto , Vejiga Urinaria/patología , Neoplasias de la Vejiga Urinaria/diagnóstico por imagen , Neoplasias de la Vejiga Urinaria/patología
3.
Encephale ; 46(6): 443-449, 2020 Dec.
Artículo en Francés | MEDLINE | ID: mdl-32192750

RESUMEN

OBJECTIVES: Hearing voices is a common experience for people with schizophrenia. Perceived voices are in most cases a source of great distress for patients. This experience also exists in the general population and is considered as "non-clinical". Much research has focused on the psychological and neuropsychological mechanisms behind the emergence of voices. With regard to voice persistence factors, the acceptance of the voice-hearing phenomenon is still relatively unexplored. In addition, there are few standardized tools that specifically assess this dimension of voice experience. The Voices Acceptance and Actions Scale (VAAS) is the only validated tool to address voice acceptance in individuals with schizophrenia. However, to date, there is no French version. The objective of this research was to validate the VAAS in a French speaking population. METHOD: Our sample consisted of individuals with schizophrenia (N=65) and voice hearers from the general population (N=321). For the clinical population, individuals with schizophrenia and auditory hallucinations were assessed using the VAAS scale in its two abbreviated versions (9 and 12 items). In order to validate the measure in French, we administered psychopathology scales (BPRS) and voice belief scales (BAVQ-R) for convergent and divergent validity. For the non-clinical population, we administered the VAAS scale online (via LimeSurvey), accompanied by a brief sociodemographic questionnaire (age, sex, country of origin, existence of medical or psychological follow-up). RESULTS: The psychometric properties of the VAAS scale were satisfactory and similar to the original English-language tool for both versions, with a slight advantage for the one with 9-items. The convergent validity measured with the BAVQ-R scale, and the divergent one measured with the BPRS depression subscale, were found to be satisfactory. In addition, the re-test performed 6 weeks after the first test (N=30) was satisfactory for both scales, with a Pearson correlation index greater than 70 (r=0.70; P<0.001 for the VAAS 9 items) and (r=0.79; P<0.001 for the 12 item version). In individuals with schizophrenia (clinical population), the level of voice acceptance was low and strongly correlated with depression. This point seems to corroborate the current data in the field suggesting that voice hearing in this population is associated with significant distress and has a significant impact on their lives. Conversely, the level of acceptance obtained from the non-clinical population was much higher, reflecting a higher level of acceptance in this population. People from the non-clinical population seemed to accept and experience their voices with less distress than people from the clinical population in this study. CONCLUSION: To date, a paucity of studies have investigated the acceptance of auditory hallucinations. Our results support the psychometric validity of the French version of the VAAS, particularly the 9-item version. Furthermore, our study supports the need to continue studying voice acceptance, as it appears to be strongly linked to depression in people with psychiatric disorders such as schizophrenia. In addition, our study is novel in that it also explored, with a standardized tool, the level of voice acceptance in a non-clinical population and found people to be more accepting of the voices they hear and better at living with them. These data provide new evidence to better understand the links between the level of acceptance of voices, their experiences, and depression. Clinically, it seems essential to conduct more systematic and regular evaluations of the level of voice acceptance in those hearing voices. Finally, in terms of rehabilitation, voice acceptance can become a therapeutic target in order to improve the psychological and behavioral functioning of the person.


Asunto(s)
Trastornos Mentales , Esquizofrenia , Alucinaciones/diagnóstico , Humanos , Psicometría , Esquizofrenia/diagnóstico , Encuestas y Cuestionarios
4.
Prog Urol ; 30(16): 1038-1044, 2020 Dec.
Artículo en Francés | MEDLINE | ID: mdl-33012630

RESUMEN

PURPOSE: In 2016, the Herault tumor registry collected 1961cancers in urology (21.4 % from all Herault cancers this year). RHESOU was created to complete RTH' data with specific parameters in onco-urology. The aim of this study is to describe RHESOU and to give some examples with our first results. MATERIAL AND METHODS: In November 2018, RHESOU (Registry HErault Specialised in Onco-Urology) was founded with the same registry recommendations. It collects specific oncologic parameters and also complete RTH's data. For each urological cancer, a specific survey with different choices was performed to collect a maximum of data which could be present in patients' file. These surveys were used for urological cancers cases that live in Herault in 2017. RESULTS: In 2017, we collected 970 prostate cancers, 581 bladder cancers, 212 kidney cancers, 51 upper excretory tract cancers, 28 testicle cancers and 9 penil cancers. Our urological data collection gives many possibilities to create many requests for detailed analysis in urological cancers. In this article, we reported data from kidney, bladder and prostate cancers. CONCLUSIONS: RHESOU is a new tool opened to the different urologic corporations (urologists, pathologists, oncologists, radiotherapists, radiologists) that permits an overview in urological cancers in Herault. Finally, one important aim is that this tool will be adapted when new treatments or new important parameters appear in the years ahead. LEVEL OF EVIDENCE: 3.


Asunto(s)
Oncología Médica , Sistema de Registros , Neoplasias Urológicas , Femenino , Francia , Humanos , Neoplasias Renales/diagnóstico , Neoplasias Renales/terapia , Masculino , Neoplasias de la Próstata/diagnóstico , Neoplasias de la Próstata/terapia , Neoplasias de la Vejiga Urinaria/diagnóstico , Neoplasias de la Vejiga Urinaria/terapia , Neoplasias Urológicas/diagnóstico , Neoplasias Urológicas/terapia
5.
Rev Neurol (Paris) ; 175(7-8): 458-463, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31296398

RESUMEN

Protein misfolding cyclic amplification assay (PMCA) and real-time quaking-induced conversion (RT-QuIC) are two amplification techniques based on the ability of PrPsc to induce a conformational change in PrP allowing the detection of minute amounts of PrPsc in body fluids or tissues. PMCA and RT-QuIC have different ability to amplify PrPsc from sporadic, variant and genetic forms of Creutzfeldt-Jakob disease (CJD). PMCA readily amplifies PrPsc from variant CJD (vCJD) tissue while RT-QuIC easily amplifies PrPsc from sporadic CJD (sCJD) patient tissues. In terms of diagnosis, this implies the possibility of distinguishing vCJD from sCJD and explains the wider use of RT-QuIC given the respective frequencies of vCJD and sCJD. The sensitivity values of RT-QuIC for the diagnosis of sCJD are comparable or higher than those of the other tests (EEG, MRI, detection of 14-3-3 or tau proteins in cerebrospinal fluid) but with a specificity close to 100%. These new diagnostic methods could also be useful for the diagnosis of other neurodegenerative diseases.


Asunto(s)
Síndrome de Creutzfeldt-Jakob/diagnóstico , Síndrome de Creutzfeldt-Jakob/microbiología , Enfermedades por Prión/diagnóstico , Enfermedades por Prión/microbiología , Humanos , Técnicas de Diagnóstico Molecular/métodos
6.
Ann Oncol ; 27(7): 1235-41, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-27029707

RESUMEN

BACKGROUND: A minority of early breast cancer (EBC) patients treated with adjuvant or neoadjuvant chemotherapy have sufficient baseline vitamin D (vitD) level. This randomized phase III study assessed the safety and efficacy of a tailored, high-dose, oral vitD supplementation in restoring a normal 25-hydroxy vitD (25OHD) level in this population. PATIENTS AND METHODS: Participants received a 6-month conventional (C) vitD and calcium supplementation or a 6-month high-dose oral vitD regimen tailored on the deficiency (T) and a conventional calcium supplementation. The primary end point was the 6-month percentage of 25OHD serum level normalization. RESULTS: A total of 215 patients including 197 patients with vitD deficiency were recruited, and 195 patients were randomized (T, 100; C, 95). Compliance to the daily oral supplementation was 68.4% and 67% in the C and T arms, respectively. Discontinuous high-dose vitD compliance appeared higher in the T arm (77%). At 6 months, more patients presented with a normalized vitD level in the T arm (30% versus 12.6%; P = 0.003). Supplementation was well tolerated, and no significant difference in the treatment-related toxicity between the two arms was reported. Fifty-two patients without vitD normalization from the C arm switched to the T arm after 6 months. At 12 months, 44% of these patients achieved vitD normalization. CONCLUSION: A tailored high-dose oral vitD supplementation safely allows a higher percentage of the serum 25OHD level normalization compared with a conventional regimen in chemotherapy-treated EBC patients. As compliance to a daily oral supplementation remains poor in this setting, an adaptation of the treatment schedule is warranted. CLINICAL TRIAL NUMBER: NCT01480869.


Asunto(s)
Neoplasias de la Mama/dietoterapia , Suplementos Dietéticos , Deficiencia de Vitamina D/dietoterapia , Vitamina D/administración & dosificación , Adulto , Anciano , Neoplasias de la Mama/sangre , Neoplasias de la Mama/patología , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/patología , Femenino , Humanos , Persona de Mediana Edad , Estadificación de Neoplasias , Calidad de Vida , Vitamina D/análogos & derivados , Vitamina D/sangre , Deficiencia de Vitamina D/sangre , Deficiencia de Vitamina D/patología
7.
Ann Oncol ; 26(5): 908-914, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25688059

RESUMEN

BACKGROUND: This randomized phase II-III trial sought to evaluate the efficacy and safety of adding bevacizumab (Bev) following induction chemotherapy (CT) in extensive small-cell lung cancer (SCLC). PATIENTS AND METHODS: Enrolled SCLC patients received two induction cycles of CT. Responders were randomly assigned 1:1 to receive four additional cycles of CT alone or CT plus Bev (7.5 mg/kg), followed by single-agent Bev until progression or unacceptable toxicity. The primary end point was the percentage of patients for whom disease remained controlled (still in response) at the fourth cycle. RESULTS: In total, 147 patients were enrolled. Partial response was observed in 103 patients, 74 of whom were eligible for Bev and randomly assigned to the CT alone group (n = 37) or the CT plus Bev group (n = 37). Response assessment at the end of the fourth cycle showed that disease control did not differ between the two groups (89.2% versus 91.9% of patients remaining responders in CT alone versus CT plus Bev, respectively; Fisher's exact test: P = 1.00). Progression-free survival (PFS) since randomization did not significantly differ, with a median PFS of 5.5 months [95% confidence interval (CI) 4.9% to 6.0%] versus 5.3 months (95% CI 4.8% to 5.8%) in the CT alone and CT plus Bev groups, respectively [hazard ratio (HR) for CT alone: 1.1; 95% CI 0.7% to 1.7%; unadjusted P = 0.82]. Grade ≥2 hypertension and grade ≥3 thrombotic events were observed in 40% and 11% of patients, respectively, in the CT plus Bev group. Serum vascular endothelial growth factor (VEGF) and soluble VEGF receptor titrations failed to identify predictive biomarkers. CONCLUSION: Administering 7.5 mg/kg Bev after induction did not improve outcome in extensive SCLC patients.


Asunto(s)
Inhibidores de la Angiogénesis/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Bevacizumab/uso terapéutico , Neoplasias Pulmonares/tratamiento farmacológico , Carcinoma Pulmonar de Células Pequeñas/tratamiento farmacológico , Adulto , Anciano , Inhibidores de la Angiogénesis/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Bevacizumab/efectos adversos , Cisplatino/uso terapéutico , Ciclofosfamida/uso terapéutico , Progresión de la Enfermedad , Supervivencia sin Enfermedad , Epirrubicina/uso terapéutico , Etopósido/uso terapéutico , Femenino , Francia , Humanos , Quimioterapia de Inducción , Estimación de Kaplan-Meier , Neoplasias Pulmonares/mortalidad , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Factores de Riesgo , Carcinoma Pulmonar de Células Pequeñas/mortalidad , Carcinoma Pulmonar de Células Pequeñas/patología , Factores de Tiempo , Resultado del Tratamiento , Adulto Joven
8.
Prog Urol ; 25(16): 1121-4, 2015 Dec.
Artículo en Francés | MEDLINE | ID: mdl-26475234

RESUMEN

INTRODUCTION: With the widespread use of prostate specific antigen (PSA) prescription and despite the automatization of PSA assessment, clinicians should not forget the analytical interference of PSA immunoassays due to the presence of heterophilic autoantibodies in a patient. MATERIAL AND METHODS: This article details some clinical cases, mechanisms involved in the interference and how to overcome this problem. RESULTS: The reported and documented interferences led to useless explorations even erroneous diagnosis. CONCLUSION: Before any unexpected PSA value in relation to the clinical symptomatology, it is strongly recommended to verify the absence of any interference before any invasive procedure or therapy modification.


Asunto(s)
Antígeno Prostático Específico/sangre , Anticuerpos Heterófilos/sangre , Autoanticuerpos/sangre , Reacciones Falso Positivas , Humanos , Masculino , Neoplasias de la Próstata/sangre , Neoplasias de la Próstata/diagnóstico
9.
Psychiatry Res ; 317: 114860, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36179593

RESUMEN

"The Accept Voices© is a useful intervention for the management and acceptance of auditory verbal hallucinations in people with schizophrenia. This study aims at determining if the clinical effects remained at six- and 12-month follow-ups. Results show that participants (N = 22) maintained a decrease in auditory hallucinations, at the six and 12 months follow ups for severity and acceptance of Voices, anxiety and depression. Accept Voices© shows promise as a potential treatment for people with schizophrenia struggling with Voices.


Asunto(s)
Esquizofrenia , Voz , Humanos , Psicología del Esquizofrénico , Alucinaciones/etiología , Alucinaciones/terapia , Esquizofrenia/complicaciones , Esquizofrenia/terapia , Ansiedad/terapia
10.
Vaccine X ; 11: 100187, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35755140

RESUMEN

Background: In December 2020, Sputnik V was incorporated to the National COVID-19 Immunization Plan in Argentina. Studies had shown 98% of antibody response rate. To date, data on immunogenicity and antibody persistence in Argentina are scarce.The objective was to assess humoral immune response after two doses of Sputnik V in Health Care Workers (HCWs) at the Ricardo Gutierrez Children's Hospital (RGCH). Methods: A prospective, cohort study in HCWs immunized with two doses of Sputnik V between February and March 2021. The following variables were assessed: age, gender, risk factors for severe COVID-19 or mortality, immunosuppressive therapy and history of SARS-CoV-2. Blood samples were drawn on the day of the first dose, 28 days and 180 days after the second. Anti-Spike IgG was measured using an ELISA assay. Differences in immune response were evaluated according to study variables. Comparison analyses between groups with or without history of infection were performed, with T-test and ANOVA or Mann-Whitney tests. For each subject, we compared baseline values with 28 days and 180 days after the second vaccine.STATA version 14 and R Sofware were used for data analyses. Results: We included 528 individuals, mean age 41.5 years, 82.9% female, 14.4% (76/528) reported previous SARS-CoV-2 infection.All subjects developed antibodies post-vaccination. At day 28, concentrations were significantly higher in previously infected than naïve subjects (p < 0.001) with no differences according to age, gender and comorbidities.At day 180, 17% (95% CI 13.17-21.53) of naïve subjects were negative. Antibody concentrations decreased significantly in all subjects except in those who reported SARS-CoV-2 infection after vaccination (n = 31). This last group had significantly higher antibody concentrations. Conclusion: This study assessed immune response to a new COVID-19 vaccine in real life in a cohort of subjects. Antibody concentrations varied according to history of SARS-COV-2 infection and decreased over time.

11.
Encephale ; 37 Suppl 1: S77-82, 2011 May.
Artículo en Francés | MEDLINE | ID: mdl-21600337

RESUMEN

BACKGROUND: Borderline personality disorder (BPD) accounts for 10% of outpatient psychiatric practice. The risk of suicide attempts is high and the psychosocial impairment significant. Different theoretical streams have suggested psychotherapeutical approaches for BPD. OBJECTIVE: to examine the efficacy of psychotherapy for BPD patients on affective symptoms, behavioural outcomes, interpersonal and social functioning, as well as BPD criteria. METHODS: We reviewed the medical literature from 1990 to 2008 on Medline by combining the following keywords "borderline personality disorder" and "psychotherapy" (inclusion criteria). We restricted the analysis to "randomised control trial" or "meta analysis". RESULTS: Of the 39 abstracts that came out from the search, we selected 17 (44%) after applying the exclusion criteria. According to our review, different types of psychotherapies have shown some efficacy on reducing affective symptoms and BPD criteria, as well as improving behavioural outcomes and psychosocial functioning. Dialectical behavioural therapy presents the best-documented efficacy, notably on reducing self-mutilating and suicidal behaviours (five randomized controlled trials [RCT]). Mentalization based treatment seems to be efficient on the four types of outcomes, but has been the object of only one RCT. Finally, some evidence suggests that Manual Assisted Cognitive Treatment and Systems Training for Emotional Predictability and Problem Solving are the most cost-effective and easiest to be implemented. CONCLUSION: According to our review, some evidence supports an efficiency of psychotherapies in the management of several features of BPD. It is likely that, depending on the target symptoms, one type of therapy might be more efficient than another. The acceptability of these long-term treatments is however unknown.


Asunto(s)
Trastorno de Personalidad Limítrofe/terapia , Psicoterapia/métodos , Afecto , Trastorno de Personalidad Limítrofe/diagnóstico , Trastorno de Personalidad Limítrofe/psicología , Humanos , Relaciones Interpersonales , Cuidados a Largo Plazo , Evaluación de Procesos y Resultados en Atención de Salud , Ensayos Clínicos Controlados Aleatorios como Asunto , Automutilación/prevención & control , Automutilación/psicología , Ajuste Social , Conducta Social , Intento de Suicidio/prevención & control , Intento de Suicidio/psicología
12.
Psychiatry Res ; 291: 113159, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32540685

RESUMEN

AIM OF THE STUDY: The objective of this study was to evaluate the potential impact of a third wave CBT group intervention for the management of auditory hallucinations in patients with schizophrenia. METHOD: 38 patients with schizophrenia presenting with auditory hallucinations, followed in mental health services, participated in six sessions of a group based on acceptance and engagement therapy (ACT). The study followed a repeated single case experimental design (type A-B-A) based on the principle of a control phase followed by an intervention phase and a follow-up phase of similar duration. The various measurements were administered during the control phase, at pre-/post-group and six weeks after the last group session. RESULTS: The results show a significant decrease in auditory hallucinations, as measured by the PSYRATS scale, during the treatment and follow-up phase, compared to the control phase. In addition, the participants saw significant reductions in depressive and anxious symptomatology (assessed with CDSS and SEAS), and increases in coping and acceptance in regards to voices (assessed using a study scale and VAAS). The level of Malevolence beliefs about voices (measured with BAVQ-R) also decreased significantly. CONCLUSIONS: A brief group intervention based acceptance show promise in the reduction of the intensity of auditory hallucinations, depression and anxiety in patients with schizophrenia, while improving their acceptance.


Asunto(s)
Terapia Cognitivo-Conductual/métodos , Manejo de la Enfermedad , Alucinaciones/psicología , Alucinaciones/terapia , Esquizofrenia/terapia , Psicología del Esquizofrénico , Adaptación Psicológica/fisiología , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Psicoterapia de Grupo/métodos , Encuestas y Cuestionarios
13.
Science ; 257(5075): 1377-80, 1992 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-17738279

RESUMEN

During the past 25 years there have been many attempts to detect a possible dust ring around the sun, with contradictory results. Before the 1991 eclipse, infrared eclipse experiments used single-element detectors to scan the corona along the ecliptic for excess surface brightness peaks. The availability of relatively large-format infrared array detectors now provides a considerable observational advantage: two-dimensional mapping of the brightness and polarization of the corona with high photometric precision. The 1991 eclipse path included the high-altitude Mauna Kea Observatory, a further advantage to measure the corona out to large angular distances from the sun. Results are reported from an experiment conducted on Mauna Kea with a HgCdTe-array detector sensitive to wavelengths between 1 and 2.5 micrometers, using broad-band J, H, and K filters. Although the sky conditions were not ideal, the H- and K-band surface brightnesses clearly show the inhomogeneous structure in the K-corona and the elliptical flattening of the F-corona, but no evidence of a circumsolar, local dust component out to 15 solar radii.

14.
Science ; 267(5202): 1282-8, 1995 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-7871424

RESUMEN

The Hubble Space Telescope made systematic observations of the split comet P/Shoemaker-Levy 9 (SL9) (P designates a periodic comet) starting in July 1993 and continuing through mid-July 1994 when the fragments plunged into Jupiter's atmosphere. Deconvolutions of Wide Field Planetary Camera images indicate that the diameters of some fragments may have been as large as approximately 2 to 4 kilometers, assuming a geometric albedo of 4 percent, but significantly smaller values (that is, < 1 kilometer) cannot be ruled out. Most of the fragments (or nuclei) were embedded in circularly symmetric inner comae from July 1993 until late June 1994, implying that there was continuous, but weak, cometary activity. At least a few nuclei fragmented into separate, condensed objects well after the breakup of the SL9 parent body, which argues against the hypothesis that the SL9 fragments were swarms of debris with no dominant, central bodies. Spectroscopic observations taken on 14 July 1994 showed an outburst in magnesium ion emission that was followed closely by a threefold increase in continuum emission, which may have been caused by the electrostatic charging and subsequent explosion of dust as the comet passed from interplanetary space into the jovian magnetosphere. No OH emission was detected, but the derived upper limit on the H2O production rate of approximately 10(27) molecules per second does not necessarily imply that the object was water-poor.


Asunto(s)
Medio Ambiente Extraterrestre , Júpiter , Sistema Solar , Atmósfera , Radical Hidroxilo/análisis , Magnesio/análisis , Análisis Espectral , Agua/análisis
15.
Science ; 292(5520): 1329-33, 2001 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-11359001

RESUMEN

At least 16 fragments were detected in images of comet C/1999 S4 (LINEAR) taken on 5 August 2000 with the Hubble Space Telescope (HST) and on 6 August with the Very Large Telescope (VLT). Photometric analysis of the fragments indicates that the largest ones have effective spherical diameters of about 100 meters, which implies that the total mass in the observed fragments was about 2 x 10(9) kilograms. The comet's dust tail, which was the most prominent optical feature in August, was produced during a major fragmentation event, whose activity peaked on UT 22.8 +/- 0.2 July 2000. The mass of small particles (diameters less than about 230 micrometers) in the tail was about 4 x 10(8) kilograms, which is comparable to the mass contained in a large fragment and to the total mass lost from water sublimation after 21 July 2000 (about 3 x 10(8) kilograms). HST spectroscopic observations during 5 and 6 July 2000 demonstrate that the nucleus contained little carbon monoxide ice (ratio of carbon monoxide to water is less than or equal to 0.4%), which suggests that this volatile species did not play a role in the fragmentation of C/1999 S4 (LINEAR).

16.
Oncogenesis ; 6(7): e366, 2017 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-28759022

RESUMEN

miR-151a and its host gene, focal adhesion kinase, FAK, are located in a region of chromosome 8q that is frequently amplified in solid tumors, including lung cancer. Lung cancer is the leading cause of cancer deaths worldwide and metastasis remains the major challenge in battling lung cancer mortality. Here, we demonstrate that miR-151a is overexpressed in non-small cell lung cancer (NSCLC) patient specimens, as compared to healthy lung. In addition, miR-151a overexpression promotes proliferation, epithelial-to-mesenchymal transition (EMT) and induces tumor cell migration and invasion of NSCLC cells. Blocking miR-151a expression using anti-miR-151a approaches significantly reduced NCSLC cell proliferative and motility potential. Furthermore, we determined that miR-151a significantly regulates E-cadherin expression. Finally, functional rescue experiments determined that overexpression of E-cadherin in miR-151a NSCLC cell lines potently repressed miR-151a-induced partial EMT and cell migration of NSCLC cells. In conclusion, our findings suggest that miR-151a functions as an oncomiR in NSCLC by targeting E-cadherin mRNA and inducing proliferation, migration and partial EMT.

17.
Science ; 355(6332): 1392-1395, 2017 03 31.
Artículo en Inglés | MEDLINE | ID: mdl-28325842

RESUMEN

The Rosetta spacecraft spent ~2 years orbiting comet 67P/Churyumov-Gerasimenko, most of it at distances that allowed surface characterization and monitoring at submeter scales. From December 2014 to June 2016, numerous localized changes were observed, which we attribute to cometary-specific weathering, erosion, and transient events driven by exposure to sunlight and other processes. While the localized changes suggest compositional or physical heterogeneity, their scale has not resulted in substantial alterations to the comet's landscape. This suggests that most of the major landforms were created early in the comet's current orbital configuration. They may even date from earlier if the comet had a larger volatile inventory, particularly of CO or CO2 ices, or contained amorphous ice, which could have triggered activity at greater distances from the Sun.

18.
Int J Biol Markers ; 21(1): 20-9, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16711510

RESUMEN

There is an increasing demand for the evaluation of HER2 status in breast cancer. In this study, sections from fixed tissues and triton extracts of tissue homogenates were obtained from 163 malignant breast tumors and analyzed in parallel using immunohistochemistry combined with fluorescence in situ hybridization, as gold standard tests, and an ELISA test (c-erbB2/c-neu Rapid Format ELISA, Oncogene Research Products, USA). Tumor DNA was employed to evaluate two quantitative PCR methods: the HER2/neu DNA Quantification Kit (Roche Diagnostics GmbH, Germany), which uses the gastrin chromosome 17 reference gene, and our recently developed Oncolab qPCR assay, where both a chromosome 17 gene (somatostatin receptor type II (SSTR2)) and a non-chromosome 17 reference gene (glyceraldehyde-3-phosphate deshydrogenase (GAPDH)) were used to detect an increase in HER2 gene copy number and to evaluate the aneusomy of chromosome 17, respectively. By IHC/FISH and ELISA, HER2 was overexpressed in 27 (16.6%) and 24 (14.7%) samples, respectively. With the Roche and Oncolab qPCR assays, 29 (17.8%) samples showed a ratio of HER2/gastrin > or = 2.0 and 26 (16.0%) showed a ratio of HER2/SSTR2 > or = 2.0, respectively. In samples presenting HER2/SSTR2 <2.0 and HER2/GAPDH > or = 2.0, which was indicative of a chromosome 17 polysomy, we observed a modest increase in HER2 protein expression. Complete agreement between the four methods for HER2 status determination was obtained for 154 (94.5%) samples. Overall, these results demonstrate that quantitative PCR is a reliable method for analyzing HER2 status and chromosome 17 polysomy.


Asunto(s)
Neoplasias de la Mama/genética , Aberraciones Cromosómicas , Cromosomas Humanos Par 17/genética , Genes erbB-2 , Reacción en Cadena de la Polimerasa/métodos , Biomarcadores de Tumor/análisis , Neoplasias de la Mama/patología , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Inmunohistoquímica , Hibridación Fluorescente in Situ , Estudios Prospectivos , Receptor ErbB-2/biosíntesis , Receptores de Estrógenos/análisis , Sensibilidad y Especificidad
19.
Science ; 354(6319): 1566-1570, 2016 12 23.
Artículo en Inglés | MEDLINE | ID: mdl-27856849

RESUMEN

The Rosetta spacecraft has investigated comet 67P/Churyumov-Gerasimenko from large heliocentric distances to its perihelion passage and beyond. We trace the seasonal and diurnal evolution of the colors of the 67P nucleus, finding changes driven by sublimation and recondensation of water ice. The whole nucleus became relatively bluer near perihelion, as increasing activity removed the surface dust, implying that water ice is widespread underneath the surface. We identified large (1500 square meters) ice-rich patches appearing and then vanishing in about 10 days, indicating small-scale heterogeneities on the nucleus. Thin frosts sublimating in a few minutes are observed close to receding shadows, and rapid variations in color are seen on extended areas close to the terminator. These cyclic processes are widespread and lead to continuously, slightly varying surface properties.

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