The lakes of Titan.

The surface of Saturn's haze-shrouded moon Titan has long been proposed to have oceans or lakes, on the basis of the stability of liquid methane at the surface. Initial visible and radar imaging failed to find any evidence of an ocean, although abundant evidence was found that flowing liquids have existed on the surface. Here we provide definitive evidence for the presence of lakes on the surface of Titan, obtained during the Cassini Radar flyby of Titan on 22 July 2006 (T16). The radar imaging polewards of 70 degrees north shows more than 75 circular to irregular radar-dark patches, in a region where liquid methane and ethane are expected to be abundant and stable on the surface. The radar-dark patches are interpreted as lakes on the basis of their very low radar reflectivity and morphological similarities to lakes, including associated channels and location in topographic depressions. Some of the lakes do not completely fill the depressions in which they lie, and apparently dry depressions are present. We interpret this to indicate that lakes are present in a number of states, including partly dry and liquid-filled. These northern-hemisphere lakes constitute the strongest evidence yet that a condensable-liquid hydrological cycle is active in Titan's surface and atmosphere, in which the lakes are filled through rainfall and/or intersection with the subsurface 'liquid methane' table.

Titan Radar Mapper observations from Cassini's T3 fly-by.

Cassini's Titan Radar Mapper imaged the surface of Saturn's moon Titan on its February 2005 fly-by (denoted T3), collecting high-resolution synthetic-aperture radar and larger-scale radiometry and scatterometry data. These data provide the first definitive identification of impact craters on the surface of Titan, networks of fluvial channels and surficial dark streaks that may be longitudinal dunes. Here we describe this great diversity of landforms. We conclude that much of the surface thus far imaged by radar of the haze-shrouded Titan is very young, with persistent geologic activity.

Metastatic neuroblastoma in infants: are survival rates excellent only within the stringent framework of clinical trials?

INTRODUCTION: SIOPEN INES protocol yielded excellent 5-year survival rates for MYCN-non-amplified metastatic neuroblastoma. Patients deemed ineligible due to lack or delay of MYCN status or late registration were treated, but not included in the study. Our goal was to analyse survival at 10 years among the whole population. MATERIALS AND METHODS: Italian and Spanish metastatic INES patients' data are reported. SPSS 20.0 was used for statistical analysis. RESULTS: Among 98 infants, 27 had events and 19 died, while 79 were disease free. Five- and 10-year event-free survival (EFS) were 73 and 70 %, and overall survival (OS) was 81 and 74 %, respectively. MYCN status was significant for EFS, but not for OS in multivariate analysis. CONCLUSIONS: The survival rates of patients who complied with all the inclusion criteria for INES trials are higher compared to those that included also not registered patients. Five-year EFS and OS for INES 99.2 were 87.8 and 95.7 %, while our stage 4s population obtained 78 and 87 %. Concerning 99.3, 5-year EFS and OS were 86.7 and 95.6 %, while for stage 4 we registered 61 and 68 %. MYCN amplification had a strong impact on prognosis and therefore we consider it unacceptable that many patients were not studied for MYCN and probably inadequately treated. Ten-year survival rates were shown to decrease: EFS from 73 to 70 % and OS from 81 to 74 %, indicating a risk of late events, particularly in stage 4s. Population-based registries like European ENCCA WP 11-task 11 will possibly clarify these data.

Metastatic neuroblastoma in infants: are survival rates excellent only within the stringent framework of clinical trials?

Introduction. SIOPEN INES protocol yielded excellent 5-year survival rates for MYCN-non-amplified metastatic neuroblastoma. Patients deemed ineligible due to lack or delay of MYCN status or late registration were treated, but not included in the study. Our goal was to analyse survival at 10 years among the whole population. Materials and methods. Italian and Spanish metastatic INES patients’ data are reported. SPSS 20.0 was used for statistical analysis. Results. Among 98 infants, 27 had events and 19 died, while 79 were disease free. Five- and 10-year event-free survival (EFS) were 73 and 70 %, and overall survival (OS) was 81 and 74 %, respectively. MYCN status was significant for EFS, but not for OS in multivariate analysis. Conclusions. The survival rates of patients who complied with all the inclusion criteria for INES trials are higher compared to those that included also not registered patients. Five-year EFS and OS for INES 99.2 were 87.8 and 95.7 %, while our stage 4s population obtained 78 and 87 %. Concerning 99.3, 5-year EFS and OS were 86.7 and 95.6 %, while for stage 4 we registered 61 and 68 %. MYCN amplification had a strong impact on prognosis and therefore we consider it unacceptable that many patients were not studied for MYCN and probably inadequately treated. Ten-year survival rates were shown to decrease: EFS from 73 to 70 % and OS from 81 to 74 %, indicating a risk of late events, particularly in stage 4s. Population-based registries like European ENCCA WP 11-task 11 will possibly clarify these data (AU)

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The sand seas of Titan: Cassini RADAR observations of longitudinal dunes.

The most recent Cassini RADAR images of Titan show widespread regions (up to 1500 kilometers by 200 kilometers) of near-parallel radar-dark linear features that appear to be seas of longitudinal dunes similar to those seen in the Namib desert on Earth. The Ku-band (2.17-centimeter wavelength) images show approximately 100-meter ridges consistent with duneforms and reveal flow interactions with underlying hills. The distribution and orientation of the dunes support a model of fluctuating surface winds of approximately 0.5 meter per second resulting from the combination of an eastward flow with a variable tidal wind. The existence of dunes also requires geological processes that create sand-sized (100- to 300-micrometer) particulates and a lack of persistent equatorial surface liquids to act as sand traps.

[Idiopathic and secondary osteoporosis in childhood]. / L'osteoporosi primitiva e secondaria in età pediatrica.

Osteoporosis is a common disease characterized by reduced bone mass, with a consequent increase in bone fragility and susceptibility to fracture risk. Bone mineral density (BMD) measurement is used to make the diagnosis of osteoporosis prior to incident fracture, and to predict fracture risk. BMD is determined by the peak bone mass achieved, and the rate and timing of subsequent bone loss. Dual-energy X-ray absorptiometry (DEXA) is the most popular and effective method utilized for osteoporosis screening. Bone disease is a side effect of concern regarding chronic glucocorticoid (GC) administration. Most GC-treated patients exhibit a process of bone loss, frequently leading to osteoporosis, with increased fracture risk, especially in spinal vertebrae. Osteogenesis imperfecta is an inherited and generalized connective tissue disorder characterized mainly by bone fragility. Idiopathic osteoporosis of childhood or adolescence without blue sclerae and other stigmata of osteogenesis imperfecta is occasionally observed and sometimes more than one sib is affected. Beta-thalassemia major is associated with significant bone disease. The etiology of the bone disease is still debatable, many factors can adversely affect bone accretion in thalassemic patients. These include delayed puberty, bone marrow expansion, the deleterious effects of desferrioxamine, iron overload and genetic factors. Current treatment alternatives of osteoporosis include bisphosphonates, calcitonin, and selective estrogen receptor modulators.

[Inherited disorders of bilirubin metabolism]. / Disordini ereditari del metabolismo della bilirubina.

Jaundice in an infant or older child may reflect accumulation of either unconjugated or conjugated bilirubin and could be related to inherited bilirubin disorders. Three grades of inherited unconjugated hyperbilirubinemia are recognised in humans. This spectrum of disorders is distinguished primarily on the basis of the plasma bilirubin level, the response to phenobarbital administration, and the presence or absence of bilirubin glucoronides in bile. The enzyme responsible for the conjugation of bilirubin is the bilirubin uridine-diphosphate-glucuronosyltransferase (UGT). Mutations in the gene encoding bilirubin-UGT (UGT1A1), lead to complete or partial inactivation of the enzyme causing the rare autosomal recessively inherited conditions, Crigler-Najjar syndrome type 1 (CN-1) and type 2 (CN-2). Gilbert syndrome (GS) is due to an insertional mutation at homozygous state of the TATAA element (seven TA repeats) of UGT1A1 producing a reduced level of expression of the gene. The association of GS with haemolytic anemias, e.g., Hereditary Spherocytosis (HS) or Congenital Dyserythropoietic Anemia type 2 (CDA 2), increase the hyperbilirubinemia level and the risk of cholelithiasis. Forms of chronic conjugated hyperbilirubinemia are Dubin-Johnson syndrome, Rotor syndrome, Alagille syndrome or arteriohepatic dysplasia, Wilson disease or hepatolenticular degeneration. Liver or liver cell transplantation is the therapy in some cases.

Cassini radar views the surface of Titan.

The Cassini Titan Radar Mapper imaged about 1% of Titan's surface at a resolution of approximately 0.5 kilometer, and larger areas of the globe in lower resolution modes. The images reveal a complex surface, with areas of low relief and a variety of geologic features suggestive of dome-like volcanic constructs, flows, and sinuous channels. The surface appears to be young, with few impact craters. Scattering and dielectric properties are consistent with porous ice or organics. Dark patches in the radar images show high brightness temperatures and high emissivity and are consistent with frozen hydrocarbons.