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1.
Trends Plant Sci ; 26(5): 496-508, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33358304

RESUMEN

Light spectral composition influences plant growth and metabolism, and has important consequences for interactions with plant-feeding arthropods and their natural enemies. In greenhouse horticulture, light spectral composition can be precisely manipulated by light-emitting diodes (LEDs), and LEDs are already used to optimize crop production and quality. However, because light quality also modulates plant secondary metabolism and defense, it is important to understand the underlying mechanisms in the context of the growth-defense trade-off. We review the effects of the spectral composition of supplemental light currently used, or potentially used, in greenhouse horticulture on the mechanisms underlying plant growth and defense. This information is important for exploring opportunities to optimize crop performance and pest management, and thus for developing resilient crop-production systems.


Asunto(s)
Iluminación , Desarrollo de la Planta , Producción de Cultivos , Luz , Plantas
2.
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.

3.
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.

4.
G Ital Med Lav Ergon ; 27(3): 332-4, 2005.
Artículo en Italiano | MEDLINE | ID: mdl-16240588

RESUMEN

The total tannin concentration was determined, using two different SPF methods, in 35 dust powdered wood species, both hard and softwood. Using direct reading-method (280 nm) the concentration varied from 2485 mg/g for Swedish pine to 35,843 mg/g for European oak (quercus robur, hardwood). The data obtained with the second method (Folin-Chocalteau) were well correlated (y = 0.9885x + 4.3373; r = 0.84; n=35) with the data obtained with the first method. The measured concentrations are usually higher in hardwood than softwood tested. Finally, a simple HPLC-DAD method was tested for gallic acid (GA), recently proposed as a marker for oak dust.


Asunto(s)
Contaminantes Ocupacionales del Aire/análisis , Polvo , Ácido Gálico/análisis , Exposición Profesional , Taninos/análisis , Madera , Cromatografía Líquida de Alta Presión , Humanos , Espectrofotometría
5.
Minerva Endocrinol ; 22(3): 75-7, 1997 Sep.
Artículo en Italiano | MEDLINE | ID: mdl-9557474

RESUMEN

A thyroid hemiagenesis in association with Hashimoto's thyroiditis and mild hypofunction in a 40 years woman, is described. It is an unusual association. The clinical, hormonal, immunological, instrumental and cytological diagnosis has been established. The importance of the scintigraphic pattern and the differential diagnosis with other pathological situations, such as Plummer's disease and several destroying processes, is emphasized. It is suggested that thyroid hemiagenesis has not to be regarded as clinically insignificant, in consideration of a possible association with pathologies of the normally developed lobe (Graves' disease, myxoedema, goiter, Hashimoto's thyroiditis, and especially neoplastic degeneration) or with nonthyroid diseases (hyperparathyroidism).


Asunto(s)
Enfermedades de la Tiroides/patología , Glándula Tiroides/crecimiento & desarrollo , Tiroiditis Autoinmune/patología , Adulto , Femenino , Humanos , Enfermedades de la Tiroides/complicaciones , Glándula Tiroides/anomalías , Tiroiditis Autoinmune/etiología
6.
Minerva Endocrinol ; 17(3): 127-31, 1992.
Artículo en Italiano | MEDLINE | ID: mdl-1338549

RESUMEN

In a 46 year old man, who arrived at our observation suffering for three months from considerable increasing weakness and progressive impairment of libido, we documented a condition of secondary hypocorticism due to an isolated ACTH deficiency associated with a reduced somatotropin reserve, the last improved after treatment with corticosteroids. We found low serum levels of ACTH and cortisol, good response of adrenal glands to corticotropin depot, normalization of the clinical board during glucocorticoid replacement. Stimulating test with CRH (corticotropin releasing hormone) did not cause a response in ACTH, suggesting the presence of primitive damage of the hypophyseal corticotroph cells.


Asunto(s)
Insuficiencia Suprarrenal/etiología , Hormona Adrenocorticotrópica/deficiencia , Hormona del Crecimiento/deficiencia , Hipopituitarismo/complicaciones , Insuficiencia Suprarrenal/tratamiento farmacológico , Cortisona/análogos & derivados , Cortisona/uso terapéutico , Combinación de Medicamentos , Humanos , Hidrocortisona/sangre , Hipopituitarismo/diagnóstico , Masculino , Persona de Mediana Edad , Prednisolona/análogos & derivados , Prednisolona/uso terapéutico
7.
Minerva Endocrinol ; 21(1): 13-8, 1996 Mar.
Artículo en Italiano | MEDLINE | ID: mdl-8786738

RESUMEN

Thyroid abnormalities were studied in 40 uremic patients half of whom were receiving hemodialysis and half peritoneal dialysis. The following parameters were examined in all patients: total and free thyroxinemia, free and total triiodothyroninemia, basal thyreotropinemia and levels 20 mins after releasing hormone (TRH) stimulation, reverse T3, thyroglobulinemia, antithyroglobulin , antimicrosomial and antithyroperoxidase antibodies; a thyroid echography was also performed. Numerous alterations were found in thyroid parameters, with a greater frequency in hemodialysed patients (65%) than those undergoing peritoneal dialysis (52.5%). Among the parameters examined it is worth noting that total thyroxinemia was significantly reduced compared to controls, and FT3 was very significantly reduced. Among those patients undergoing peritoneal dialysis thyreotropinemia was increased in 6 cases (15%), whereas among hemodialysed patients it was reduced in 2 cases (5%). Ten patients (25%) in all appeared to be free of thyroid alterations and 30 (75%) showed one or more alteration of the parameters examined. Of the latter, 1 case of toxic multinodular goiter, 1 case of Plummer's adenoma in a pretoxic phase, 1 case of hypothyroidism, 15 cases of "sick euthyroid of syndrome", 3 cases with high antibody levels and 2 cases of single node goitre were diagnosed. The study confirmed the high incidence of thyroid alterations in uremic patients and, surprisingly, allowed the authors to diagnose a case of toxic multinodular goitre and a case of Plummer's adenoma at a pretoxic phase. The authors discuss the rarity of thyroid hyperfunction in uremia and suggest the need to consider patients with chronic renal insufficiency as being at risk of hypo-, normo- and hyperfunctioning thyreopathy, and to use a routine thyreotropinemia assay in all uremic patients.


Asunto(s)
Diálisis Renal/efectos adversos , Hormonas Tiroideas/sangre , Uremia/complicaciones , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pruebas de Función de la Tiroides , Uremia/terapia
8.
Minerva Med ; 68(4): 229-34, 1977 Feb 21.
Artículo en Italiano | MEDLINE | ID: mdl-840419

RESUMEN

The effect of oral clonidine on prothrombin time, partial thromboplastin time, blood fibrinogen, fibrinolytic activity and platelet count was investigated in 25 hypertensive and 7 normal subjects. High plasma fibrinogen levels were present in 80% of the hypertensive patients and prolonged lysis time in 28%; the means values were 487 +/- 135 mg % and 223 +/- 62 min., respectively. The other coagulation tests were normal. 0,300-0,450 mg/day clonidine per os for 15 days both decreased fibginogen levels (mean 406 +/- 149; p less than 0.05) and shortened lysis time (mean 153 +/- 78 min; p less than 0.005). No changes were noted in the normal subjects. The pathophysiological mechanism of these findings is discussed and their possible implications for the treatment of hypertension are emphasised.


Asunto(s)
Coagulación Sanguínea/efectos de los fármacos , Clonidina/farmacología , Hipertensión/sangre , Viscosidad Sanguínea/efectos de los fármacos , Clonidina/uso terapéutico , Fibrinólisis/efectos de los fármacos , Humanos , Hipertensión/tratamiento farmacológico , Agregación Plaquetaria/efectos de los fármacos
9.
Minerva Cardioangiol ; 45(9): 429-33, 1997 Sep.
Artículo en Italiano | MEDLINE | ID: mdl-9446064

RESUMEN

Patients with chronic obstructive pulmonary disease (COPD), especially during acute exacerbations of their disease, show a greater incidence of cardiac arrhythmias than healthy subjects of the same age. The type of arrhythmias found may be supraventricular (premature atrial beats, paroxysmal supraventricular tachycardia, multifocal atrial tachycardia, atrial flutter, atrial fibrillation) or ventricular (premature ventricular beats, sustained ventricular tachycardia, torsades de pointes, ventricular fibrillation) that may lead to sudden cardiac death. The pathogenesis of arrhythmias is complex and many factors may be involved such as hypoxemia, hypercapnia, respiratory acidosis, metabolic and respiratory alchalosis, hypokalemia, concomitant ischemic heart disease, chronic cor pulmonale, left ventricular diastolic dysfunction. Remarkable attention has been drawn to the possible arrhythmogenic effect of drugs such as theophylline, beta-adrenergic stimulants and digitalis which are commonly used in the therapy of COPD. Both of the main classes of bronchodilators (methylxanthynes and beta-adrenergic agonists), even when used together, apparently do not increase the incidence of dangerous cardiac arrhythmias. However, these drugs should be used with caution in the elderly, in patients with preexisting cardiac arrhythmias, with heart disease or with reduced hepatic function. In these cases Holter monitoring, repeated measurements of plasma drugs concentration and prompt hospitalization of high risk patients in Intensive Care Unit may be needed.


Asunto(s)
Arritmias Cardíacas/etiología , Bronconeumonía/complicaciones , Enfermedades Pulmonares Obstructivas/fisiopatología , Taquicardia Paroxística/etiología , Agonistas Adrenérgicos beta/efectos adversos , Agonistas Adrenérgicos beta/uso terapéutico , Arritmias Cardíacas/inducido químicamente , Arritmias Cardíacas/diagnóstico , Broncodilatadores/uso terapéutico , Bronconeumonía/diagnóstico , Bronconeumonía/tratamiento farmacológico , Glicósidos Digitálicos/efectos adversos , Glicósidos Digitálicos/uso terapéutico , Electrocardiografía Ambulatoria , Humanos , Enfermedades Pulmonares Obstructivas/diagnóstico , Enfermedades Pulmonares Obstructivas/tratamiento farmacológico , Taquicardia Paroxística/inducido químicamente , Taquicardia Paroxística/diagnóstico , Teofilina/efectos adversos , Teofilina/uso terapéutico
10.
Recenti Prog Med ; 84(10): 698-708, 1993 Oct.
Artículo en Italiano | MEDLINE | ID: mdl-7694335

RESUMEN

Symptomatic and anti-thyroid drugs are discussed under the profile of the way of action, of the pharmacologic characters, of attack and maintenance doses and of unwanted effects. The time of treatment and the criteria (still not satisfactory) to decide the moment suitable to stop it are also considered. To the light of latest acquisitions some particular aspects of therapy about thyrotoxic storm, treatment during pregnancy, pharmacologic preparation to surgery, treatment of ophthalmopathy are discussed. To conclude, present medical therapy (or, alternatively, surgical and radioisotopic) allow satisfactorily to control the disease; it's possible, in the shown cases, to advise a prolonged pharmacologic treatment with antithyroid drugs.


Asunto(s)
Enfermedad de Graves/tratamiento farmacológico , Antitiroideos/efectos adversos , Antitiroideos/farmacología , Antitiroideos/uso terapéutico , Femenino , Enfermedad de Graves/etiología , Enfermedad de Graves/cirugía , Humanos , Yoduros/uso terapéutico , Yodo/antagonistas & inhibidores , Embarazo , Cuidados Preoperatorios , Crisis Tiroidea/tratamiento farmacológico
11.
Recenti Prog Med ; 87(9): 422-4, 1996 Sep.
Artículo en Italiano | MEDLINE | ID: mdl-9053957

RESUMEN

A case of rhabomyolysis with attendant severe acute renal failure, arisen in a 59-year-old male treated with haloperidol-decanoate, is presented. The patient has been affected by paranoia schizophrenia since childhood, and he was treated with electroshock and successively with neuroleptics p.o. Four years before our observation, a therapy with haloperidol decanoate (50 mg i.m. monthly) was started. After some time, catatonic like episodes appeared, which got more and more frequent, until they appeared weekly. In occasion of the last of them, he was admitted to our hospital. At the objective examination he presented psychomotory arrest, perspiration, mytacism, severe muscle rigidity, moderate oedems to lower limbs. Laboratory findings showed a pattern consistent with rabdomyolysis and severe renal failure. After that haloperidol decanoate was stopped and rehydration and intensive diuretic therapy was started, the clinical and laboratory pattern went normal, persisting however a light creatinine increase. Probably the rhabdomyolysis was induced by the haloperidol decanoate, and renal failure by secondary severe hyvolemia. This case comes into the so-called neuroleptic malignant syndrome which can rarely arise in patients treated with antipsycotic agents and which causes high mortality, particularly when there are rhabdomyolysis and acute renal failure.


Asunto(s)
Lesión Renal Aguda/inducido químicamente , Antipsicóticos/efectos adversos , Haloperidol/análogos & derivados , Síndrome Neuroléptico Maligno/etiología , Rabdomiólisis/inducido químicamente , Haloperidol/efectos adversos , Humanos , Masculino , Persona de Mediana Edad
12.
Science ; 334(6055): 487-90, 2011 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-22034428

RESUMEN

Images obtained by the Optical, Spectroscopic, and Infrared Remote Imaging System (OSIRIS) cameras onboard the Rosetta spacecraft reveal that asteroid 21 Lutetia has a complex geology and one of the highest asteroid densities measured so far, 3.4 ± 0.3 grams per cubic centimeter. The north pole region is covered by a thick layer of regolith, which is seen to flow in major landslides associated with albedo variation. Its geologically complex surface, ancient surface age, and high density suggest that Lutetia is most likely a primordial planetesimal. This contrasts with smaller asteroids visited by previous spacecraft, which are probably shattered bodies, fragments of larger parents, or reaccumulated rubble piles.

13.
Science ; 327(5962): 190-3, 2010 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-20056887

RESUMEN

The European Space Agency's Rosetta mission encountered the main-belt asteroid (2867) Steins while on its way to rendezvous with comet 67P/Churyumov-Gerasimenko. Images taken with the OSIRIS (optical, spectroscopic, and infrared remote( )imaging system) cameras on board Rosetta show that Steins is an oblate body with an effective spherical diameter of 5.3 kilometers. Its surface does not show color variations. The morphology of Steins is dominated by linear faults and a large 2.1-kilometer-diameter crater near its south pole. Crater counts reveal a distinct lack of small craters. Steins is not solid rock but a rubble pile and has a conical appearance that is probably the result of reshaping due to Yarkovsky-O'Keefe-Radzievskii-Paddack (YORP) spin-up. The OSIRIS images constitute direct evidence for the YORP effect on a main-belt asteroid.

17.
Blut ; 46(3): 149-54, 1983 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-6824795

RESUMEN

Three members of the same family were found to have a clotting defect consistent with the diagnosis of heterozygous factor X Friuli disorder. The main features of the defect were a mild prolongation of prothrombin time and partial thromboplastin time, but a normal Stypven-Cephalin clotting time. Factor X activity was 40-50% of normal using tissue thromboplastin, but was perfectly normal using Russell's viper venom and cephalin. Using chromogenic substrate S-2222 the level was 30% of normal. Immunologically, factor X was normal. Bleeding manifestations were mild if any. The hereditary pattern was autosomal. The family comes from an area far away from Friuli and represents the first example of factor X Friuli discovered outside the Friuli.


Asunto(s)
Trastornos de la Coagulación Sanguínea/genética , Factor X , Adulto , Trastornos de la Coagulación Sanguínea/epidemiología , Niño , Femenino , Heterocigoto , Humanos , Italia , Tiempo de Tromboplastina Parcial , Linaje , Tiempo de Protrombina
18.
Icarus ; 110(2): 287-91, 1994 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11539179

RESUMEN

Near-infrared (J, H and K bands) spectra of nine dark asteroids (chosen among a sample of supposed primitive objects between C and D classes) have been obtained at the Mauna Kea Observatory (Hawaii) with the 2.2-m telescope using KSPEC as spectrograph. The aim of this work was to search for evidence of the presence of organic materials in these objects as found in other planetary bodies as 5145 Pholus, and in some cometary nuclei. A careful analysis of the data has revealed flat or slightly redder spectra than the solar one for all observed asteroids. No evidence of distinct absorption features was found.


Asunto(s)
Astronomía/instrumentación , Evolución Planetaria , Planetas Menores , Sistema Solar , Espectroscopía Infrarroja Corta/instrumentación , Carbono , Medio Ambiente Extraterrestre
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