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1.
Nature ; 627(8004): 505-509, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38418881

RESUMO

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.

3.
Scand J Rheumatol ; 44(6): 474-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26169842

RESUMO

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.


Assuntos
Citocinas/sangue , Índice de Gravidade de Doença , Espondilartrite/sangue , Espondilartrite/fisiopatologia , Rigidez Vascular/fisiologia , Biomarcadores/sangue , Proteína C-Reativa/metabolismo , Estudos de Casos e Controles , Feminino , Humanos , Interleucina-1beta/sangue , Interleucina-6/sangue , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Análise de Onda de Pulso , Fator de Necrose Tumoral alfa/sangue
4.
Orig Life Evol Biosph ; 44(3): 231-7, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25573749

RESUMO

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.


Assuntos
Euryarchaeota/efeitos da radiação , Geobacillus/efeitos da radiação , Simulação de Ambiente Espacial , Sulfolobus solfataricus/efeitos da radiação , Thermotoga neapolitana/efeitos da radiação , Temperatura Baixa , Dessecação , Euryarchaeota/crescimento & desenvolvimento , Exobiologia , Meio Ambiente Extraterreno , Geobacillus/crescimento & desenvolvimento , Temperatura Alta , Marte , Viabilidade Microbiana/efeitos da radiação , Sulfolobus solfataricus/crescimento & desenvolvimento , Thermotoga neapolitana/crescimento & desenvolvimento , Raios Ultravioleta , Vácuo
5.
Acta Neurol Scand ; 73(1): 66-70, 1986 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-3006422

RESUMO

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.


Assuntos
Neoplasias Encefálicas/tratamento farmacológico , Carmustina/uso terapêutico , Cisplatino/uso terapêutico , Glioblastoma/tratamento farmacológico , Lomustina/uso terapêutico , Células Cultivadas , Resistência a Medicamentos , Humanos , Ensaio Tumoral de Célula-Tronco
6.
Acta Neurol Scand ; 72(4): 414-8, 1985 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-3002083

RESUMO

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.


Assuntos
Neoplasias Encefálicas/tratamento farmacológico , Carmustina/uso terapêutico , Glioblastoma/tratamento farmacológico , Fatores Etários , Anticorpos Monoclonais/imunologia , Antineoplásicos/uso terapêutico , Neoplasias Encefálicas/imunologia , Criança , Pré-Escolar , Relação Dose-Resposta a Droga , Proteína Glial Fibrilar Ácida/imunologia , Glioblastoma/imunologia , Antígenos HLA/imunologia , Humanos , Técnicas In Vitro , Compostos de Nitrosoureia/uso terapêutico , Estreptozocina/análogos & derivados , Estreptozocina/uso terapêutico
8.
Minerva Anestesiol ; 46(4): 479-84, 1980 Apr.
Artigo em Italiano | MEDLINE | ID: mdl-7454015

RESUMO

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.


Assuntos
Anestesia Obstétrica , Anestesia , Piperazinas , Propanidida , Trazodona , Adulto , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Menores , Medicação Pré-Anestésica , Gravidez , Fatores de Tempo
9.
Neurosurgery ; 5(3): 376-7, 1979 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-503301

RESUMO

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.


Assuntos
Papiledema/complicações , Pseudotumor Cerebral/diagnóstico , Adulto , Humanos , Pressão Intracraniana , Masculino , Pseudotumor Cerebral/complicações
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