Deexcitation Dynamics of Muonic Atoms Revealed by High-Precision Spectroscopy of Electronic K X Rays.

We observed electronic K x rays emitted from muonic iron atoms using superconducting transition-edge sensor microcalorimeters. The energy resolution of 5.2 eV in FWHM allowed us to observe the asymmetric broad profile of the electronic characteristic Kα and Kß x rays together with the hypersatellite K^{h}α x rays around 6 keV. This signature reflects the time-dependent screening of the nuclear charge by the negative muon and the L-shell electrons, accompanied by electron side feeding. Assisted by a simulation, these data clearly reveal the electronic K- and L-shell hole production and their temporal evolution on the 10-20 fs scale during the muon cascade process.

Observation of threshold effects in positron scattering from the noble gases.

Channel coupling is a phenomenon that has been investigated for many scattering processes, and is responsible for the formation of cusps or steps in the cross sections for open scattering channels at, or near, the onset of a new scattering channel. It has long been speculated that the opening of the positronium formation channel may lead to the formation of such cusp features in the elastic positron scattering cross section. In this work, elastic scattering of positrons has been measured in the region of the positronium formation threshold for the noble gases He-Xe. Cusplike behavior is observed and, while the features which are observed appear broad, they represent a magnitude of between 4 and 15% of the total elastic cross section. No evidence is found of any other features in this region, at least within the uncertainty of the present data, discounting the possibility of scattering resonances.

Bone health as a primary target in the pediatric age.

Bone tissue is constantly renewed during childhood and adolescence to assure skeleton growth both in size and mineral density: up to 90 percent of peak bone mass is acquired by age 18 in girls and age 20 in boys, which makes youth the best time to "invest" in bone health. The reduction in bone mineral density leading to compromised strength and microarchitecture of bone tissue can favour the occurrence of fragility fractures in the pediatric age. Assessing the normality of bone density measurements in childhood by current methods is hampered by the lack of normative control data. The understanding of factors useful for maximizing peak bone mass, as well as the knowledge of diagnostic tools and therapeutic strategies for managing a state of reduced bone mineral density are crucial to prevent fractures throughout lifetime.

Bone mineral density and body composition in a myelomeningocele children population: effects of walking ability and sport activity.

Myelomeningocele causes serious locomotor disability, osteoporosis and pathologic fractures. The aim of this study was to investigate the relationship between body composition, bone mineral density, walking ability and sport activity in myelomeningocele children. 60 patients aged between 5 and 14 yrs with myelomeningocele (22 ambulatory and 38 non-ambulatory), were studied. Fat mass and fat-free-mass were calculated by anthropometry. The bone mineral density at lumbar and femoral neck were evaluated. Bone mineral density at the lumbar and femoral neck was lower than in the normal population. In the non-ambulaty group, bone mineral density was approximately 1 SD lower than in the ambulatory one (p < 0.01). Fat mass was greater than expected but without significantly differences between walking group (mean 26%) and wheel-chair users (25%). Patients practised sport activity had a better bone mineral density and body fat compared with other patients with the same disability. Patients with myelomeningocele have decreased bone mineral density and are at higher risk of pathologic bone fractures. All subjects showed an excess of fat as percentage of body weight and are shorter than normal children. The measurement of bone mineral density may help to identify those patients at greatest risk of suffering of multiple fractures. Walk ability and sport activity, associated with the development of muscle mass, are important factors in promoting bone and body growth, to reduce the risk of obesity and of pathological fractures.

Non-invasive diagnosis in a case of bronchopulmonary sequestration and proposal of diagnostic algorithm.

The case of a 43-year-old woman with intralobar pulmonary sequestration, Pryce type one, is presented. The medical history was characterised by recurrent bronchopneumonia, productive cough with purulent sputum and hemoptysis in the last three years. Diagnosis was made by CT angiography: multiplanar, maximum intensity projection and volume rendering reconstructions were visualised. A volume reduction of middle and lower lobe with multiple cyst-like bronchiectasis was detected and no evident relationship with tracheobronchial tree was pointed out. Reconstructions aimed at evaluating bronchial structures demonstrated no patency of middle and lower lobar bronchi. The study carried out after contrast medium infusion in arterial phase showed a vascular disorder characterised by an accessory arterial branch arising from the upper portion of thoracic aorta which, after moving caudally to pulmonary hilus with a tortuous course, supplied the atelectatic parenchyma. No anomalous venous drainage was detected. The patient underwent surgery with resection of two pulmonary lobes. CT compares favourably with other alternative imaging technique for pulmonary sequestration as multiplanar reconstructions allow not only the detection of supplying vessel, but also the accurate description of heterogeneous characteristics of the mass and adjacent structures. Finally an imaging-based diagnostic algorhithm is proposed.

Glucose-induced thermogenesis in postobese women who have undergone biliopancreatic diversion.

We evaluated the metabolic response to a standard (75-g) oral-glucose-tolerance test (OGTT) in eight post-obese women (PO) who underwent biliopancreatic diversion and in eight healthy control women (C). All subjects had been weight-stable for > or = 2 y. Blood samples for glucose, insulin, C-peptide, and nonesterified free fatty acids were taken at baseline and during 180 min after the glucose load. Plasma glucose and insulin concentrations at baseline and during the OGTT were similar in the two groups, suggesting the absence of an insulin-resistant state in the PO. Continuous indirect calorimetry was performed throughout the test. Glucose-induced thermogenesis (GIT) was higher in PO than in C (8.6 +/- 2.6 vs 4.3 +/- 1.9%; P < 0.01). These data indicate that GIT and insulin-glucose metabolism are not impaired in postobese patients when a near ideal body weight is reached and maintained after weight loss; this suggests that thermogenic deficiencies and hyperinsulinemia-insulin resistance are alterations secondary to obesity.

Secondary skeletal involvement in Sanfilippo syndrome.

BACKGROUND: Sanfilippo syndrome, or mucopolysaccharidosis (MPS) type III, is a rare lysosomal storage disease, resulting from errors in the catabolism of heparan sulphate. AIM: To evaluate bone turnover and bone mineral density (BMD) in MPS type III patients. DESIGN: Clinical and observational study. METHODS: We evaluated serum markers of bone formation or resorption, and measured BMD using dual-energy X-ray absorptiometry (DEXA), in three patients with MPS type III. RESULTS: Serum vitamin D were low, and BMDs greatly reduced at lumbar and femoral sites, indicating the possibility of osteoporosis and osteomalacia. DISCUSSION: These skeletal effects probably result from nutritional deficiencies and inability to walk, rather than from the genetic defect itself. Secondary skeletal involvement in patients with MPS type III may represent a considerable cause of morbidity, and requires interventions to reduce the risk of pathological fractures.

Determination of the non-enzymatic glycation of hemoglobin by isoelectrofocusing of its globin chains.

Micro cation exchange chromatography determination of HbA1c does not provide a complete picture of Hb glycation, for it does not determine all the glycated forms of hemoglobin. For the determination of total glycation, we describe here a rod IEF method, which allows the simultaneous quantitation of glycation on alpha and beta globin chains. The method exhibits good sensitivity; it is not affected by artifacts deriving from temperature, hypertriglyceridemia, Hb variants or labile HbA1 (aldiminic Hb). The results obtained indicate that in a normal population approximately 18% of the beta chain and 8% of the alpha chain are glycated. These mean percentages increase in the diabetic to 28% and 12%, respectively. The beta chain is glycated on both valine and lysine residues, while the alpha chain is glycated only on the latter. HbA1 values from micro cation exchange chromatography are significantly related to both alpha and beta glycation. Thus, valinic or lysinic glycation have roughly the same clinical significance.

Correlates of osteoporosis in chronic obstructive pulmonary disease.

The aim of this study was to analyse the correlates of reduced bone mineral density in patients with chronic obstructive pulmonary disease (COPD), with special regard to a possible protective role of hypercapnia. One hundred and four consecutive COPD inpatients in stabilized respiratory conditions underwent a comprehensive assessment of their health status. Bone mineral density was measured by X-ray absorptiometry at the lumbar site and at the femoral neck site. Differences in health-related variables between patients with (group O, n=62) and without (group N, n=42) lumbar and/or femoral neck osteoporosis were assessed first by univariate analysis and then by logistic regression analysis aimed to identify independent correlates of osteoporosis. Group O was characterized by worse nutritional status, as reflected by indices exploring either lean or fat mass, and by a trend towards lower forced expiratory volume in 1 sec/forced vital capacity ratio. Arterial tension of carbon dioxide lacked any correlation with bone mineral density. According to the logistic regression analysis, body mass index < or = 22 kg m(-2) qualified as the only and positive independent correlate of osteoporosis (odds ratio=4.18; 95% confidence intervals=1.19-14.71). In conclusion, malnutrition characterizes COPD patients with osteoporosis, while mild to moderate hypercapnia lacks either a positive or negative effect on bone mineral density. Longitudinal studies are needed to identify predictors rather than correlates of bone mineral density.

[Hepatic hemangioma: limitations of echo-scintigraphic diagnosis]. / L'emangioma epatico: limiti della diagnosi eco-scintigrafica.

The Authors report a case of percutaneous liver biopsy of a solitary hepatic lesion complicated by a serious haemorrhage. By a timely surgical operation an hepatic hemangioma has been detected. The lack of diagnostic accuracy of the echo-scintigraphic detection in assessing a solitary hepatic lesion is analyzed.

[Wegener's granulomatosis. Clinical and radiologic considerations and description of 3 cases]. / La granulomatosi di Wegener. Considerazioni cliniche e radiologiche con descrizione di 3 casi.

The clinical, radiological and pathological findings, natural history and response to treatment are investigated in 3 patients. They represent the only examples of W.G. who were seen over a 15 year period at our University Hospital and are characteristic of generalize and limited form. The role of immune complexes in the pathogenesis of W.G. and diagnostic importance of pulmonary radiological pattern are described.

[Familial Mediterranean fever and electroencephalographic changes. A clinical case]. / Febbre familiare mediterranea e alterazioni elettroencefalografiche. Caso clinico.

The Authors describe the case of a non-Hebrew Italian girl suffering from short-lasting fever episodes, associated with abdominal colic, since the age of 3. The occurrence of acute arthrosynovitis during the last episode, at 12 years of age, clinically confirms the diagnosis of familial mediterranean fever, as previously supposed. The increase in urinary coproporphyrins, with normal values of delta-aminolevulinic acid and porphobilinogen poses the problem of the differential diagnosis between hereditary coproporphyria and secondary coproporphinuria. The importance of this case lies in the presence of electroencephalographic alteration since the first years of life, suggesting a temporal epilepsy for which the patient was at length submitted to anti-epileptic treatment. Electroencephalographic alterations, of different type and uneasy interpretation, are described in the literature with a frequency which does not seem accidental. Renal biopsy does not show amyloid, nor the RMN reveals cerebral abnormalities. The anti-epileptic therapy being withdrawn, the patient was treated with daily administrations of colchicine (1 mg/die); 18 months after, she is disease free.

[Hypersplenism in surgery]. / Ipersplenismi in chirurgia.

We studied 86 patients suffering from hypersplenism, associated with portal hypertension (39 patients), hematologic disease (45 patients) and with Gaucher's disease (2 patients). Inclusion criteria were the presence of thrombocytopenia < 100.000 x mm3 and leucopenia < 4.000 x mm3. No meaningful differences about the improvement of hypersplenism in portal hypertension were observed between the patients submitted to shunt and splenectomy and those submitted to shunt only. On the contrary, splenectomy caused a quick normalization of the leukothrombocytopenia in the patients suffering from hematologic disease, which, moreover, allowed to perform radio- and chemotherapy in those suffering from malignancies. We reported absence of mortality and a low and aspecific morbidity.

[Rare causes of serious digestive hemorrhages]. / Le gravi emorragie digestive da cause rare.

The rare causes of massive hemorrhage in the gastrointestinal tract are not completely classifiable. They are characterized by high variability, as shown in several isolated reports. In our experience of 17 cases, clinical and endoscopic features were sometimes typical of a rare pathology, others were referable to common pathologies and exactly diagnosed only by angiography or surgery. Our experience points out the difficulties in the surgical prescription and timing, when the endoscopic diagnosis was lacking or unsure, or when a massive haemorrhagic recurrence forced diagnostic laparatomy. The role of endoscopy and the advantages of intraoperative enteroscopy have been compellingly demonstrated. Diagnostic and therapeutic angiography has been the main method in vascular hemorrhage.