Liver involvement in pediatric celiac disease

Celiac disease (CD) is an intestinal inflammatory disease that manifests in genetically susceptible individuals when exposed to dietary gluten. It is a common chronic disorder, with a prevalence of 1% in Europe and North America. Although the disease primarily affects the gut, the clinical spectrum of CD is remarkably varied, and the disease can affect many extraintestinal organs and systems, including the liver. The hepatic dysfunction presenting in CD ranges from asymptomatic liver enzyme elevations or nonspecific reactive hepatitis (cryptogenic liver disorders), to chronic liver disease. In this article, we review the clinical presentations and possible mechanisms of CD-related liver injury to identify strategies for the diagnosis and treatment of these disorders in childhood

The Relationship between Catalyst Precursors and Chain End Groups in Homogeneous Propene Polymerization Catalysis

The chain transfer to monomer reactions promoted by primary and secondary growing chains in the propene polymerization promoted by ansa-zirconocenes and postmetallocene precursors are studied by using DFT methods. From the theoretical results it comes out that the prevalence of propene insertion over b-hydrogen transfer to the monomer decreases drastically in the presence of a secondary chain. Furthermore, we explained the reason why C2-symmetric metallocene catalysts promote the selective formation of cis but-2-enyls end group after a 2,1 inserted unit whereas for octahedral bis(phenoxy- imine)titanium-based catalysts, chain release promotes exclusively the formation of allyl terminated chain end. These results might be useful to design ligand precursors able to obtain not only high Mn PP polymers but also tuned chain end groups to build new polymer architectures. Overall, a more general picture of the enantioselectivity of the chain transfer to monomer processes is reported

β-arrestin 2 deletion improves cardiac function during aging

BACKGROUND: The pathophysiological changes of the aging human heart include left ventricular (LV) hypertrophy, diastolic dysfunction, increased cardiac fibrosis and reduced inotropic reserve. These changes make aged myocardium more susceptible to stress, leading to a high prevalence of cardiovascular diseases in the elderly population. The application of genetically modified aged mice has provided direct evidence of several critical molecular mechanisms involved in cardiac aging, such as altered adrenergic signaling. Importantly, both animal and human studies have shown an age-related β-adrenergic receptor (β-AR) dysfunction but the main mechanism involved is still unknown. Physiologically, when β-ARs are stimulated by agonists, the G protein-coupled receptor kinase 2 (GRK2) phosphorylates β-ARs that then become targets for binding of β-arrestins. This β-arrestin binding prevents their further coupling to the G protein, reducing the level of functional receptors and inducing their internalization. OBJECTIVE: In the present study we have tested the effects of β-arrestin-2 deletion on cardiac function and signaling in a murine model of aging. METHODS AND RESULTS: Genetically engineered, β-arrestin 2 KO and corresponding wild type (WT) male mice were enrolled to study physiological aging. We found that β-arrestin-2 deletion in aged mice is able to: a)improve LV contractility and dilatation b)enhance average and regional cardiac radial strain as well as radial SR during c)restore age-related cardiac β-AR desensitization d)reduce cardiac oxidative stress. CONCLUSIONS: Our study shows that β-arrestin 2 has a detrimental effect on the aged heart. β-arrestin 2 deletion reverses cardiac dysfunction and LV dilatation during aging. As a contributing mechanism, improved LV function is associated with restored β-AR density and reduced oxidative stress in aged hearts. Further, our results suggest β-arrestin 2 as a potential therapeutic target to limit age-related cardiac dysfunction

Extraordinary blowing snow transport events in East Antarctica

In the convergence slope/coastal areas of Antarctica, a large fraction of snow is continuously eroded and exported by wind to the atmosphere and into the ocean. Snow transport observations from instruments and satellite images were acquired at the wind convergence zone of Terra Nova Bay (East Antarctica) throughout 2006 and 2007. Snow transport features are well-distinguished in satellite images and can extend vertically up to 200 m as first-order quantitatively estimated by driftometer sensor FlowCapt™. Maximum snow transportation occurs in the fall and winter seasons. Snow transportation (drift/blowing) was recorded for ~80% of the time, and 20% of time recorded, the flux is >10-2 kg m-2 s-1 with particle density increasing with height. Cumulative snow transportation is ~4 orders of magnitude higher than snow precipitation at the site. An increase in wind speed and transportation (~30%) was observed in 2007, which is in agreement with a reduction in observed snow accumulation. Extensive presence of ablation surface (blue ice and wind crust) upwind and downwind of the measurement site suggest that the combine processes of blowing snow sublimation and snow transport remove up to 50% of the precipitation in the coastal and slope convergence area. These phenomena represent a major negative effect on the snow accumulation, and they are not sufficiently taken into account in studies of surface mass balance. The observed wind-driven ablation explains the inconsistency between atmospheric model precipitation and measured snow accumulation value. © 2009 The Author(s)

Complete Resolution of Retroperitoneal Lymphangioma with a Single Trial of OK-432 in an Infant

Retroperitoneal lymphangioma is extremely rare. Although these neoplasms are benign, they can grow progressively with subsequent compression and infiltration of the adjacent structures. Surgical excision is demanding when the lesion surrounds vital structures and it is generally fraught with a high recurrence and morbidity rate. We report the case of a huge retroperitoneal lymphangioma in a newborn treated successfully with intracystic injection of OK-432

Adrenal pheochromocytoma incidentally discovered in a patient with parkinsonism

To evaluate the diagnostic route of pheochromocytoma (PHEO) in a patient under dopaminergic treatment. A 70-year-old man with Parkinsonism and under treatment with levodopa and carbidopa came to our observation for evaluation of arterial hypertension and right adrenal mass discovered incidentally. To evaluate adrenal hormone levels we performed a dexamethasone suppression test, plasma aldosterone levels and 24-hr urinary metanephrine, which revealed elevated levels of catecholamines metabolities. 123-I-metaiodobenzylguanidine SPECT scintiscan revealed raised activity within the right adrenal gland concordant with the mass. The diagnosis of PHEO was posed and an elective laparoscopic adrenalectomy was performed; histopathological examination confirmed the PHEO diagnosis. Recently the coexistence of PHEO and Parkinsonism is a very rare association of diseases, with only 3 cases reported in literature. In this article, another case is reported and diagnostic procedures are discusse

The impact of nonalcoholic fatty liver disease on renal function in children with overweight/obesity

The association between nonalcoholic fatty liver disease (NAFLD) and chronic kidney disease has attracted interest and attention over recent years. However, no data are available in children. We determined whether children with NAFLD show signs of renal functional alterations, as determined by estimated glomerular filtration rate (eGFR) and urinary albumin excretion. We studied 596 children with overweight/obesity, 268 with NAFLD (hepatic fat fraction >= 5% on magnetic resonance imaging) and 328 without NAFLD, and 130 healthy normal-weight controls. Decreased GFR was defined as eGFR < 90 mL/min/1.73 m(2). Abnormal albuminuria was defined as urinary excretion of >= 30 mg/24 h of albumin. A greater prevalence of eGFR < 90 mL/min/1.73 m2 was observed in patients with NAFLD compared to those without liver involvement and healthy subjects (17.5% vs. 6.7% vs. 0.77%; p < 0.0001). The proportion of children with abnormal albuminuria was also higher in the NAFLD group compared to those without NAFLD, and controls (9.3% vs. 4.0% vs. 0; p < 0.0001). Multivariate logistic regression analysis revealed that NAFLD was associated with decreased eGFR and/or microalbuminuria (odds ratio, 2.54 (confidence interval, 1.16-5.57); p < 0.05) independently of anthropometric and clinical variables. Children with NAFLD are at risk for early renal dysfunction. Recognition of this abnormality in the young may help to prevent the ongoing development of the disease

Structural characterization of syndiotactic propylene-styrene-ethylene terpolymers

The structural features of propylene-styrene-ethylene terpolymer (sP/(S-E)) prepd. using syndiospecific Cs-sym. metallocene catalyst, isopropylidene(cyclopentadienyl)-(9-fluorenyl)zirconium dichloride with MAO co-catalyst were studied. The polymorphism studies of as-prepd., melt-crystd., and fiber sP/(S-E) confirmed that ethylene units are mainly bound to styrene units arising from catalyst reactivation after the secondary insertion of styrene. Styrene-ethylene units are mainly segregated in the amorphous phase. The bulky styrene units, bound to ethylene, prevent the inclusion of ethylene units in the crystals of syndiotactic polypropylene (sPP), as generally occurs for copolymers of sPP with ethylene. This explains the fact that the effect of styrene-ethylene units on polymorphism of sPP is smaller than that obsd. in copolymers of sPP contg. only ethylene or butene comonomer units

Crystal structure of the clathrate form of syndiotactic poly(p-methylstyrene) containing o-dichlorobenzene

The crystal structure of the clathrate form of syndiotactic poly(p-methylstyrene) (s-PPMS) containing o-dichlorobenzene (o-DCB) is presented. The structure is characterized by polymer chains in s(2/1)2 helical conformation and o-dichlorobenzene molecules packed in a monoclinic unit cell with axes a = 23.4 Å, b = 11.8 Å, c = 7.7 Å, and γ = 115°, according to the space group P21/a. The calculated crystalline density is 1.07 g/cm3 for two polymer chains (eight monomer units) and two o-DCB molecules included in the unit cell. The o-DCB molecules occupy cavities delimited by the phenyl rings of two enantiomorphic polymer chains. A disorder in the positioning of the o-DCB molecules inside the cavity is present. A comparison with the crystal structure of the clathrate form of s-PPMS containing tetrahydrofuran is presented. Remarkable differences were found, confirming the previous hypothesis that two different types of crystal structures (α and β class) are presented by the clathrate forms of s-PPMS depending on the guest molecule

Polymorphic Behavior of Copolymers of Syndiotactic Polystyrene with m-Methylstyrene.

The influence of the presence of different amounts m-methylstyrene (m-MS), in the composition range 4−21 mol %, on the polymorphic behavior of syndiotactic polystyrene (s-PS) is presented. A comparison with the effect of the presence of p-methylstyrene is also presented. The behavior of copolymers subjected to solvent extraction or annealing procedures indicates that the presence of m-MS stabilizes the γ form of s-PS, which remains stable in a large temperature range, up to 210−220 °C. The helical mesoporous δ form of s-PS has not been observed in copolymers with m-MS. The presence of low contents of m-MS induces crystallization of the β form from polymer solution (by casting at high temperatures), whereas high concentrations of m-MS tend to stabilize the γ form. The copolymer samples crystallize from the melt in α and β forms depending on the concentration of m-MS, which stabilizes the β form for composition around 11 mol %, and induces crystallization in the α form for lower (4 mol %) and higher (21 mol %) concentration. Moreover, even when the memory of the α form is maintained in the melt, the presence of m-MS in a concentration around 11 mol % induces the crystallization of the β form, whereas, even though no memory of the α form is present in the melt, samples with 4 and 21 mol % of m-MS crystallize in the α form. The α form obtained in these copolymers, by melt-crystallization or annealing of the γ form, does not correspond to neither the disordered α‘, nor the ordered α‘ ‘ modifications observed in s-PS. The presence of m-MS comonomeric units induces structural variation in the crystal packing of the trans-planar chains, and a new crystalline form is obtained