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1.
Astron Astrophys ; 5972017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28008188

RESUMO

CONTEXT: The mechanism behind the shaping of bipolar planetary nebulae is still poorly understood. It is becoming increasingly clear that the main agents must operate at their innermost regions, where a significant equatorial density enhancement should be present and related to the collimation of light and jet launching from the central star preferentially towards the polar directions. Most of the material in this equatorial condensation must be lost during the asymptotic giant branch as stellar wind and later released from the surface of dust grains to the gas phase in molecular form. Accurately tracing the molecule-rich regions of these objects can give valuable insight into the ejection mechanisms themselves. AIMS: We investigate the physical conditions, structure and velocity field of the dense molecular region of the planetary nebula NGC 6302 by means of ALMA band 7 interferometric maps. METHODS: The high spatial resolution of the 12CO and 13CO J=3-2 ALMA data allows for an analysis of the geometry of the ejecta in unprecedented detail. We built a spatio-kinematical model of the molecular region with the software SHAPE and performed detailed non-LTE calculations of excitation and radiative transfer with the shapemol plug-in. RESULTS: We find that the molecular region consists of a massive ring out of which a system of fragments of lobe walls emerge and enclose the base of the lobes visible in the optical. The general properties of this region are in agreement with previous works, although the much greater spatial resolution of the data allows for a very detailed description. We confirm that the mass of the molecular region is 0.1 M⊙. Additionally, we report a previously undetected component at the nebular equator, an inner, younger ring inclined ~60° with respect to the main ring, showing a characteristic radius of 7.5×1016 cm, a mass of 2.7×10-3 M⊙, and a counterpart in optical images of the nebula. This inner ring has the same kinematical age as the northwest optical lobes, implying it was ejected approximately at the same time, hundreds of years after the ejection of the bulk of the molecular ring-like region. We discuss a sequence of events leading to the formation of the molecular and optical nebulae, and briefly speculate on the origin of this intriguing inner ring.

2.
Prostate Cancer Prostatic Dis ; 20(1): 105-109, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27958385

RESUMO

BACKGROUND: A significant number of patients with minimal lymph node disease at radical prostatectomy (RP) and pelvic lymph node dissection (PLND) have better than expected long-term outcomes. We explored whether stratification by number of positive nodes enhances our institutional prediction model for biochemical recurrence after RP. METHODS: A total of 7789 patients underwent RP and pelvic lymph node dissection from 1995 to 2012 at a tertiary referral center. We compared two recurrence prediction models: one incorporated lymph node invasion and the other tracked the number of positive nodes. Existing and updated models' discrimination was assessed using Harrell's c-index and calibration. The 10-fold cross-validation was performed to correct for model overfitting. RESULTS: Of the 491 patients (6.3%) harboring nodal disease, 387 (5.0%) had 1-2 positive nodes and 104 (1.3%) had ⩾3 positive nodes. Data on number of positive nodes did not improve the c-index for the cohort as a whole. When we assessed discrimination for node-positive patients only, c-index for the model with number of positive nodes was 0.01 (95% confidence interval 0.001-0.024) higher than the model with lymph node invasion. Illustrative examples were provided by reclassification tables using number of positive lymph nodes. For instance, 40 of 7789 patients would be reclassified with a cutoff point of 50% for biochemical recurrence at 1 year, and 36 of 7789 patients would be reclassified with a cutoff point of 40% for biochemical recurrence at 10 years. CONCLUSIONS: Stratification by number of positive lymph nodes provided additional discriminative ability for evaluating risk in node-positive patients. Pending external validation, this model could be used for patient counseling and clinical trial stratification in this subpopulation.


Assuntos
Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/cirurgia , Idoso , Humanos , Estimativa de Kaplan-Meier , Linfonodos/patologia , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Recidiva Local de Neoplasia , Estadiamento de Neoplasias , Nomogramas , Período Pós-Operatório , Prognóstico , Modelos de Riscos Proporcionais , Prostatectomia , Neoplasias da Próstata/mortalidade
3.
Nature ; 519(7541): 63-5, 2015 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-25686608

RESUMO

The planetary nebula stage is the ultimate fate of stars with masses one to eight times that of the Sun (M(⊙)). The origin of their complex morphologies is poorly understood, although several mechanisms involving binary interaction have been proposed. In close binary systems, the orbital separation is short enough for the primary star to overfill its Roche lobe as the star expands during the asymptotic giant branch phase. The excess gas eventually forms a common envelope surrounding both stars. Drag forces then result in the envelope being ejected into a bipolar planetary nebula whose equator is coincident with the orbital plane of the system. Systems in which both stars have ejected their envelopes and are evolving towards the white dwarf stage are said to be double degenerate. Here we report that Henize 2-428 has a double-degenerate core with a combined mass of ∼1.76M(⊙), which is above the Chandrasekhar limit (the maximum mass of a stable white dwarf) of 1.4M(⊙). This, together with its short orbital period (4.2 hours), suggests that the system should merge in 700 million years, triggering a type Ia supernova event. This supports the hypothesis of the double-degenerate, super-Chandrasekhar evolutionary pathway for the formation of type Ia supernovae.

4.
Eur J Ophthalmol ; 16(5): 728-32, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17061225

RESUMO

PURPOSE: To report the changing patterns of ocular manifestations in human immunodeficiency virus (HIV) seropositive patients treated with highly active antiretroviral therapy (HAART). METHODS: The clinical charts of HIV seropositive patients, 735 examined from 1997 to 2003 and treated with HAART for at least 2 months (Group 1), and 838 untreated examined from 1988 to 1995 (Group 2), were reviewed to assess the frequency of ocular manifestations. RESULTS: HIV-related retinal microangiopathy and opportunistic retinal infections (cytomegalovirus retinitis and toxoplasmic retinochoroiditis) were significantly higher in Group 2 than 1 (p<0.0001), while in patients treated with HAART a statistically significant increase in the frequency of chalazion (p<0.0001), diabetic and hypertensive retinopathy (p<0.0001), lipid arc of the cornea (p<0.0001), cataract and glaucoma (p<0.0001), and uveitis (p=0.026) was observed. CONCLUSIONS: HAART therapy has induced a dramatic decrease in the incidence of HIV-related microangiopathy and opportunistic retinal infection and the occurrence of new lesions related both to the metabolic alterations induced by HAART and to immune reconstitution, such as uveitis.


Assuntos
Terapia Antirretroviral de Alta Atividade/métodos , Oftalmopatias/etiologia , Soropositividade para HIV/tratamento farmacológico , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Oftalmopatias/epidemiologia , Feminino , Seguimentos , Soropositividade para HIV/complicações , Humanos , Incidência , Lactente , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos
5.
Nature ; 422(6930): 405-8, 2003 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-12660776

RESUMO

Some classes of stars, including novae and supernovae, undergo explosive outbursts that eject stellar material into space. In 2002, the previously unknown variable star V838 Monocerotis brightened suddenly by a factor of approximately 10(4). Unlike a supernova or nova, it did not explosively eject its outer layers; rather, it simply expanded to become a cool supergiant with a moderate-velocity stellar wind. Superluminal light echoes were discovered as light from the outburst propagated into the surrounding, pre-existing circumstellar dust. Here we report high-resolution imaging and polarimetry of those light echoes, which allow us to set direct geometric distance limits to the object. At a distance of >6 kpc, V838 Mon at its maximum brightness was temporarily the brightest star in the Milky Way. The presence of the circumstellar dust implies that previous eruptions have occurred, and spectra show it to be a binary system. When combined with the high luminosity and unusual outburst behaviour, these characteristics indicate that V838 Mon represents a hitherto unknown type of stellar outburst, for which we have no completely satisfactory physical explanation.

6.
Int J Artif Organs ; 23(5): 319-24, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10872850

RESUMO

139 patients undergoing cardiac surgery were included in a prospective, randomized trial. Patients were randomly allocated to receive cardiopulmonary bypass (CPB) with Trillium Biopassive Surface (TBS Group) coated oxygenators or conventional circuits (control group). 112 patients were studied with respect to postoperative biochemical profile; a subgroup of 27 patients was studied with respect to perioperative complement (C3a) activation. Patients in the TBS group demonstrated a significantly lower white blood cell count at the end of the operation (p=0.036) and a significantly higher platelet count the day after the operation (p=0.023) when compared to the control group. C3a was significantly higher (p=0.02) in the TBS group after 30 minutes of CPB, but the C3a increase after protamine administration was significantly less pronounced in the TBS group vs. the control group. Further studies involving platelet and leukocyte activation are required to better elucidate the action of this new coating in the setting of routine CPB.


Assuntos
Materiais Biocompatíveis , Ponte Cardiopulmonar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
7.
Minerva Chir ; 52(1-2): 113-5, 1997.
Artigo em Italiano | MEDLINE | ID: mdl-9102596

RESUMO

The treatment of postoperative chronic thoracic fistulas with fibrin glue can be the non-operative ideal solution for the relative simplicity of the execution technique.


Assuntos
Fístula Brônquica/terapia , Fístula Cutânea/terapia , Adesivo Tecidual de Fibrina , Humanos , Masculino , Pessoa de Meia-Idade
8.
Minerva Chir ; 52(1-2): 123-8, 1997.
Artigo em Italiano | MEDLINE | ID: mdl-9102598

RESUMO

The authors report two cases of malignant fibrous histiocytoma localised in the gluteus maximus and re-evaluate some clinical and biological aspects of the neoplasia. Although its histiogenesis is still unsure, the tumour can be classified into various isotopes: the vorticoid-polymorphous variety (70%), and the myxoid, giant cell, angiomatous and inflammatory varieties. It is the most common soft tissue sarcoma in adults and onset is most frequently observed on the trunk and limbs. Biological behaviour shows a marked tendency to local recidivation, with metastatic diffusion occurring mainly late. The choice of therapy consists of more or less radical surgical removal with or without ratio- and immunotherapy. The results of surgery are influenced by the technique used, and the biological and clinical behaviour of the tumour; in view of the numerous case reports of anomalous behaviour, these factors are only indicative. Therapeutic efficacy is on the whole greater in cases of tumours with diameters of less than 5 cm and more superficial localisations compared to the deep muscular fascia.


Assuntos
Histiocitoma Fibroso Benigno , Músculo Esquelético , Idoso , Nádegas , Feminino , Histiocitoma Fibroso Benigno/diagnóstico , Histiocitoma Fibroso Benigno/cirurgia , Humanos , Pessoa de Meia-Idade
9.
G Chir ; 16(11-12): 497-501, 1995.
Artigo em Italiano | MEDLINE | ID: mdl-8679401

RESUMO

The Authors report a case of Poland's syndrome formerly undergone reconstructive surgery with unsatisfactory results. Therefore, a new surgical reconstructive strategy having aesthetic purposes is illustrated.


Assuntos
Síndrome de Poland/cirurgia , Cirurgia Plástica/métodos , Adulto , Estética , Humanos , Masculino , Síndrome de Poland/etiologia , Reoperação
10.
G Chir ; 16(11-12): 510-11, 1995.
Artigo em Italiano | MEDLINE | ID: mdl-8679404

RESUMO

The Authors report their experience in the application of local anesthesia during breast prosthesis implantation.


Assuntos
Anestesia Local , Implantes de Mama , Mamoplastia , Adulto , Anestesia Local/métodos , Anestesia Local/normas , Feminino , Humanos
15.
Am J Psychother ; 34(4): 564-71, 1980 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7446803

RESUMO

A seminar utilizing a videotaped course of actual consecutive psychotherapy sessions with an experienced therapist and his patient has unique advantages in teaching concepts of transference. The experience provides a role model that demonstrates the therapeutic use of transference. Learning takes place by identification with the therapist on cognitive, affective, and experiential levels.


Assuntos
Psiquiatria/educação , Materiais de Ensino , Transferência Psicológica , Gravação de Videoteipe , Internato e Residência , Estados Unidos
16.
J Clin Psychiatry ; 39(6): 493-6, 1978 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-659372

RESUMO

The disorder of affect has been a traditional, but subjective, diagnostic criterion for schizophrenia. This paper offers a more precise definition. A brief review of Bleuler's concepts is included as background. The face as an important indicator of schizophrenic affect is discussed. The concept of affect disorder is then reconsidered in terms of four parameters: range, mobility, appropriateness, communicability.


Assuntos
Afeto , Psicologia do Esquizofrênico , Sintomas Afetivos/diagnóstico , Emoções , Expressão Facial , Humanos , Esquizofrenia/diagnóstico
17.
J Relig Health ; 17(4): 227-32, 1978 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24318438

RESUMO

This paper presents observations on the assets and liabilities of the parish clergy as a mental health resource within the community. These observations are drawn from a ten-year program of continuing education for cleargy in mental health, which focuses on daily pastoral experience. The parish setting is similar in many respects to the service area of a community mental health center. The clergy's assets often include availability, experience, tradition, and the special significance of the religious leader. Inadequate training in mental health skills and the complex demands of parish life are among the problems confronting the clergy in this area. On the whole, the pastoral role offers a unique and highly useful opportunity for positive psychological intervention.

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