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1.
Nature ; 627(8004): 505-509, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38418881

RESUMEN

The Double Asteroid Redirection Test (DART) had an impact with Dimorphos (a satellite of the asteroid Didymos) on 26 September 20221. Ground-based observations showed that the Didymos system brightened by a factor of 8.3 after the impact because of ejecta, returning to the pre-impact brightness 23.7 days afterwards2. Hubble Space Telescope observations made from 15 minutes after impact to 18.5 days after, with a spatial resolution of 2.1 kilometres per pixel, showed a complex evolution of the ejecta3, consistent with other asteroid impact events. The momentum enhancement factor, determined using the measured binary period change4, ranges between 2.2 and 4.9, depending on the assumptions about the mass and density of Dimorphos5. Here we report observations from the LUKE and LEIA instruments on the LICIACube cube satellite, which was deployed 15 days in advance of the impact of DART. Data were taken from 71 seconds before the impact until 320 seconds afterwards. The ejecta plume was a cone with an aperture angle of 140 ± 4 degrees. The inner region of the plume was blue, becoming redder with increasing distance from Dimorphos. The ejecta plume exhibited a complex and inhomogeneous structure, characterized by filaments, dust grains and single or clustered boulders. The ejecta velocities ranged from a few tens of metres per second to about 500 metres per second.

2.
Scand J Rheumatol ; 44(6): 474-9, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26169842

RESUMEN

OBJECTIVE: The aim of this study was to investigate the relationship between immunoinflammatory markers and indexes of arterial stiffness in patients with seronegative spondyloarthritis (SpA). METHOD: We enrolled consecutive patients with inflammatory seronegative SpA referred to a rheumatology outpatient clinic. Control subjects were patients admitted in the same period for any cause other than chronic inflammatory disease or acute cardiovascular and cerebrovascular events. Carotid-femoral pulse wave velocity (PWV) was measured and the aortic pressure waveform was used to calculate the augmentation index (Aix). We also evaluated plasma levels of C-reactive protein (CRP), interleukin (IL)-1ß, tumour necrosis factor (TNF)-α, and interleukin (IL)-6 as markers of immunoinflammatory activation. RESULTS: This study enrolled 53 patients with SpA and 55 control subjects. After adjustment for blood glucose, cholesterol, and triglyceride levels, and systolic (SBP) and diastolic blood pressure (DBP), patients with seronegative SpA showed higher mean PWV and Aix compared to controls. Moreover, in patients with seronegative SpA, we observed higher mean plasma levels of IL-6, IL-1ß, and TNF-α in subjects with mean PWV > 8 m/s in comparison with those with PWV < 8 m/s. Multivariate analysis revealed a significant association between PWV > 8 m/s and male gender, age, diabetes, hypertension, low density lipoprotein cholesterol (LDL-C) > 120 mg/dL, total cholesterol (TC) > 200 mg/dL, coronary artery disease (CAD), microalbuminuria, carotid plaque, and plasma levels of IL-6, IL-1ß, and TNF-α. CONCLUSIONS: These findings emphasize the role of inflammatory variables and metabolic factors in indexes of high arterial stiffness. Thus, an inflammatory-metabolic background may influence the pathogenesis of increased arterial stiffness in seronegative inflammatory arthritis.


Asunto(s)
Citocinas/sangre , Índice de Severidad de la Enfermedad , Espondiloartritis/sangre , Espondiloartritis/fisiopatología , Rigidez Vascular/fisiología , Biomarcadores/sangre , Proteína C-Reactiva/metabolismo , Estudios de Casos y Controles , Femenino , Humanos , Interleucina-1beta/sangre , Interleucina-6/sangre , Masculino , Persona de Mediana Edad , Análisis Multivariante , Análisis de la Onda del Pulso , Factor de Necrosis Tumoral alfa/sangre
3.
Orig Life Evol Biosph ; 44(3): 231-7, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25573749

RESUMEN

In this work we investigated the ability of four extremophilic bacteria from Archaea and Bacteria domains to resist to space environment by exposing them to extreme conditions of temperature, UV radiation, desiccation coupled to low pressure generated in a Mars' conditions simulator. All the investigated extremophilic strains (namely Sulfolobus solfataricus, Haloterrigena hispanica, Thermotoga neapolitana and Geobacillus thermantarcticus) showed a good resistance to the simulation of the temperature variation in the space; on the other hand irradiation with UV at 254 nm affected only slightly the growth of H. hispanica, G. thermantarcticus and S. solfataricus; finally exposition to Mars simulated condition showed that H. hispanica and G. thermantarcticus were resistant to desiccation and low pressure.


Asunto(s)
Euryarchaeota/efectos de la radiación , Geobacillus/efectos de la radiación , Simulación del Espacio , Sulfolobus solfataricus/efectos de la radiación , Thermotoga neapolitana/efectos de la radiación , Frío , Desecación , Euryarchaeota/crecimiento & desarrollo , Exobiología , Medio Ambiente Extraterrestre , Geobacillus/crecimiento & desarrollo , Calor , Marte , Viabilidad Microbiana/efectos de la radiación , Sulfolobus solfataricus/crecimiento & desarrollo , Thermotoga neapolitana/crecimiento & desarrollo , Rayos Ultravioleta , Vacio
5.
Neurosurgery ; 5(3): 376-7, 1979 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-503301

RESUMEN

An obese young man presented the typical features of benign intracranial hypertension (BIH), including raised intracranial pressure. Despite elevated intracranial pressure, papilledema did not develop. The syndrome resolved after medical treatment and, on examination 6 months later, the patient was normal. The absence of papilledema in this case is discussed together with data available from the literature.


Asunto(s)
Papiledema/complicaciones , Seudotumor Cerebral/diagnóstico , Adulto , Humanos , Presión Intracraneal , Masculino , Seudotumor Cerebral/complicaciones
6.
Minerva Anestesiol ; 46(4): 479-84, 1980 Apr.
Artículo en Italiano | MEDLINE | ID: mdl-7454015

RESUMEN

A brief general survey of the "anaesthesiological problem" is followed by the presentation of a method for use in ultra-short anaesthesia. Particular stress is laid on the importance that must be ascribed to premedication, even in situations of this type. The drug of choice is trazodone. An account is given of the main features of this synthetic molecule, and the details of its administration are described. Reference is also made to a series of 792 minor obstetric and gynaecological operations in which the method was employed. The size and range of this series are regarded as an outstanding aspect of the paper.


Asunto(s)
Anestesia Obstétrica , Anestesia , Piperazinas , Propanidida , Trazodona , Adulto , Anciano , Femenino , Humanos , Persona de Mediana Edad , Procedimientos Quirúrgicos Menores , Medicación Preanestésica , Embarazo , Factores de Tiempo
7.
Acta Neurol Scand ; 73(1): 66-70, 1986 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-3006422

RESUMEN

With the use of the Human Brain Tumor Stem Cell Assay (HBTSCA) in a cross-resistance study, four early (3-4) culture passages of human malignant gliomas (glioblastoma multiforme) were tested for in vitro chemosensitivity with three of the most effective single agents for brain tumor chemotherapy: BCNU, CCNU and cisplatinum (DDP). The shapes of the dose-response curves indicated complete cross-resistance between BCNU and CCNU, i.e. two chloroethyl-nitrosoureas sharing a common alkylating-carbamoylating activity, with no evident cross-resistance between the two nitrosoureas and the DDP, a DNA binder with a putatively different antitumor action. Probably because of differences in drug delivery kinetics or in the cytotoxic mechanism, DDP might play a role in the treatment of nitrosourea-resistant gliomas.


Asunto(s)
Neoplasias Encefálicas/tratamiento farmacológico , Carmustina/uso terapéutico , Cisplatino/uso terapéutico , Glioblastoma/tratamiento farmacológico , Lomustina/uso terapéutico , Células Cultivadas , Resistencia a Medicamentos , Humanos , Ensayo de Tumor de Célula Madre
8.
Acta Neurol Scand ; 72(4): 414-8, 1985 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-3002083

RESUMEN

Like all chloroethyl-nitrosoureas of major clinical use, 1,3 bis-(2-chloroethyl)-1-nitrosourea (BCNU) - which is one of the most effective chemotherapeutic agents for CNS malignancies - biologically degrades into active alkylating and carbamoylating moieties. Using a human brain tumor stem cell assay, we analyzed a series of anaplastic astrocytomas of pediatric age, characterized by different degrees of BCNU-resistance. Early (2-4) passage cultures from these tumors were treated in vitro with model drugs for alkylation (BCNU, CHLZ (2-[3-(2-chloroethyl)-3-nitrosoureido]-2-deoxy-D-glucopyranose), ENU (N-ethyl-N-nitrosourea), cross-linking (BCNU, CHLZ) and carbamoylation BHCNU (1,3 bis (trans-4-hydrocyclohexyl)-1-nitrosourea): dose-schedules were compatible with clinically achievable levels. Results of chemosensitivity tests confirmed that - as previously reported in malignant gliomas of the adult - cellular resistance to BCNU was closely related to the cross-linking activity of alkylating species. However, in pediatric gliomas the levels of cell kill after treatment with the purely carbamoylating agent BHCNU, even at the highest doses tested, were lower than expected.


Asunto(s)
Neoplasias Encefálicas/tratamiento farmacológico , Carmustina/uso terapéutico , Glioblastoma/tratamiento farmacológico , Factores de Edad , Anticuerpos Monoclonales/inmunología , Antineoplásicos/uso terapéutico , Neoplasias Encefálicas/inmunología , Niño , Preescolar , Relación Dosis-Respuesta a Droga , Proteína Ácida Fibrilar de la Glía/inmunología , Glioblastoma/inmunología , Antígenos HLA/inmunología , Humanos , Técnicas In Vitro , Compuestos de Nitrosourea/uso terapéutico , Estreptozocina/análogos & derivados , Estreptozocina/uso terapéutico
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