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Efficient procedures based on the use of iodine for the aromatization of a series of terpenoids possessing diene and homoallylic or allylic alcohol functionalities are described. Different examples are reported as a proof-of-concept study. Furthermore, iodine also proved to mediate the dehydrogenation of testosterone.

Aneurysmal disease is uncommon in children, and its presence often leads to suspicion of genetic disorders (Loeys-Dietz syndrome, Marfan syndrome, Ehlers-Danlos syndrome, tuberous sclerosis), trauma, and infection. We describe the case of a newborn boy with generalized left lower limb hypoplasia associated with diffuse areas of arteriectasis combined with areas of stenosis and fusiform aneurysms of the iliac, femoral, and popliteal arteries. No additional vascular territories were affected. The patient was asymptomatic, and no therapeutic intervention has been considered. Numerous complementary imaging and laboratory examinations failed to establish a definitive diagnosis. This collection of findings has not been previously reported.

Congenital extrahepatic portosystemic shunt (CEPS) is a rare condition in which the portomesenteric blood drains into a systemic vein, bypassing the liver through a complete or partial shunt. Most often, the diagnosis is made primarily with Doppler ultrasonography. Computed tomographic angiography and magnetic resonance angiography are used for further classification of the shunt and assessment of accompanying anomalies. Conventional angiography is necessary when results of the other tests disagree or are inconclusive. CEPS is classified into two types according to the pattern of anastomoses between the portal vein and systemic vein. In type 1, intrahepatic portal venous supply is absent; in type 2, intrahepatic portal venous supply is preserved. Type 1 usually occurs in girls with associated malformations, such as situs ambiguous with polysplenia and congenital heart defects. Associated anomalies are less frequent in type 2, and symptoms usually develop later without a gender preference. Hepatic encephalopathy and liver dysfunction are possible complications of both types and usually develop during adulthood. Both types are also associated with regenerative hepatic nodules. The clinical setting and imaging appearance of these nodules can help one avoid misdiagnosis. Definitive treatment of CEPS is determined by the type of shunt. Liver transplantation is the only effective treatment for symptomatic type 1 CEPS; surgical closure or embolization of the shunt is the therapeutic approach for type 2.

A case of heterotopic gastric mucosa in the common bile duct, cystic duct and gallbladder is reported in a 3-year-old girl with abdominal pain and jaundice. Abdominal US and CT showed dilatation of the biliary tree and a well-defined mass in the common bile duct that narrowed its lumen. The gallbladder was contracted in both examinations. The common bile duct and the gallbladder were resected and a choledochojejunostomy was performed. Although gastric heterotopy has been described throughout the entire length of the gastrointestinal tract, it is a very uncommon finding in the gallbladder and extremely rare in the biliary tree. A firm diagnosis of gastric heterotopia is based on the presence of fundal mucosa replete with parietal and chief cells. To our knowledge, this is the fifth reported case of heterotopic gastric tissue within the common bile duct, and the first to describe the US and CT findings. A relevant literature review and brief outline of the histological and radiological features are included in the discussion.

Objetivo El proposito de este estudio fue determinar el valor de la hidronefrosis leve o moderada, detectada mediante ecografia, en recien nacidos y lactantes como indicador de reflujo vesicoureteral (RVU) y evaluar la necesidad de realizar cistouretrografia miccional (CUMS) en estos pacientes. Material y metodos Se revisaron las CUMS de 237 pacientes (174 ninos y 63 ninas, con edades comprendidas entre 0 y 18 meses) con hi-dronefrosis leve detectada por ecografia, para valorar la presencia de RVU primario. Los pacientes con reflujo secundario o los que presen-taban anomalias que imposibilitaban la graduacion exacta del reflujo se excluyeron; sin embargo, cuando se observo reflujo en un rinon normal, contralateral al rinon con hidronefrosis, se incluyo en el estudio. Para el analisis estadistico de los datos, cada rinon se considero por se-parado, sumando un total de 474 rinones. Se diagnostico hidronefrosis leve cuando se observo un diametro anteroposterior de la pelvis renal de 0,5-1,5 cm. Para la graduacion del reflujo en la CUMS se utilizo el sistema internacional. Resultados De las 474 unidades renales evaluadas, 306 mostraron hidronefrosis leve en la ecografia. Solo 98 de estas (32%) presentaron reflujo (14 grado I, 50 grado II, 32 grado III y 2 grado IV). La ecogra-fia fue normal (no mostro hidronefrosis) en 52 unidades renales con reflujo (31%), contralaterales al rinon hidronefrotico, a pesar de que 38 de estas unidades tenian reflujo grado II o superior. La ecografia mos-tro hidronefrosis leve en 208 rinones que no tenian reflujo en la CUMS (68%). Conclusiones No hubo diferencias significativas en la incidencia de RVU entre los rinones con o sin hidronefrosis. La hidronefrosis leve se correlaciona escasamente con la presencia y el grado de reflujo en neonatos y lactantes y, por tanto, no debe considerarse una indicacion para realizar CUMS.

Los shunts portosistemicos se realizan para paliar la hipertension portal sintomatica o para descomprimir la vascularizacion hepatica en pacientes con sindrome de Budd-Chiari. La mayoria de los shunts por-tosistemicos quirurgicos pueden estudiarse adecuadamente mediante ecografia complementada con Doppler color y pulsado si se compren-de la hemodinamica de los procedimientos quirurgicos. Este articulo muestra la utilidad y limitaciones de la ecografia duplex Doppler en la evaluacion de los shunts portosistemicos realizados a pacientes pedia-tricos. El Doppler pulsado proporciona informacion sobre la naturaleza y direccion del flujo sanguineo y el Doppler color es capaz de mostrar directamente el shunt y, en la mayoria de los casos, permite localizar las anastomosis. Los tipos de shunts que se muestran incluyen espleno-renal proximal y distal, portocava y mesocava. Se ilustran los tipos de conexiones vasculares y se muestra la direccion posquirurgica espera-ble del flujo en los vasos sanguineos implicados. Se discute la tecnica ecografica y los criterios para determinar la permeabilidad vascular. Asi mismo se enfatizan las ventajas, limitaciones y dificultades diag-nosticas de las distintas modalidades del Doppler.

A detailed experimental and theoretical study corroborates that the reductive deoxygenation of activated (allylic or benzylic) alcohols with excess Ti(III) proceeds via an allyl(benzyl)-radical and allyl(benzyl)-Ti, which is protonated, regioselectively in the case of allylic derivatives. The H atom of the newly formed C–H bond in the product originates from the –OH group of the starting material. The deoxygenation of lithium alkoxides or alcohols by using 1.0 mol of Ti(III) leads to the corresponding dimerization products in good yields. An excellent agreement with the experimental data was obtained by using a reaction kinetics simulator to discriminate between competing reactions.

A wide spectrum of congenital anomalies may affect the upper gastrointestinal tract, including anomalies of the esophagus (e.g., atresia, fistulas, webs, duplications, vascular rings), stomach (e.g., congenital gastric outlet obstruction, duplications), and duodenum (e.g., atresia, annular pancreas, duplications, malrotation). The evaluation of affected patients can require multiple imaging modalities for diagnosis and surgical planning. Radiography is often diagnostic and specific and can usually provide important clues to help determine the optimal diagnostic procedure. Neonates with complete gastric or upper intestinal obstruction do not usually require further radiologic evaluation after radiography: Barium studies are usually contraindicated, and complementary procedures (e.g., ultrasound [US], computed tomography [CT]) are not usually helpful and may even delay surgery, resulting in death. Nevertheless, US has become important in the evaluation of the pediatric gastrointestinal tract and is being used in an increasing number of applications. CT and magnetic resonance imaging are unsuitable for general screening but provide superb anatomic detail and added diagnostic specificity. They are especially useful in demonstrating esophageal duplications and vascular rings as well as associated abnormalities. However, the decision to perform a given imaging examination should be considered carefully to avoid inconvenience or unnecessary radiation exposure to the patient or delays in surgical correction. Quality control programs should be in place to ensure safe, effective radiologic practice through use of up-to-date equipment and good imaging technique.

Ultrasonography (US) is a rapid, accurate, noninvasive method of evaluating ocular and orbital disease. A wide spectrum of pediatric ocular and orbital disorders can be demonstrated with US: ocular congenital malformations, vitreoretinal disorders, primary and metastatic ocular and orbital neoplasms, inflammatory and congestive disease (focal or systemic), cystic disease, trauma, and foreign bodies. US may be the method of choice for studying ocular congenital anomalies and vitreoretinal disorders owing to its high definition and noninvasiveness. In ocular neoplasms, US demonstrates the morphology of the lesion, its solid or liquid nature, and the presence of calcifications. Its use is limited when the tumor extends outside the globe; computed tomography (CT) or magnetic resonance (MR) imaging must then be performed. In ocular trauma, US precisely demonstrates the presence of hemorrhage, retinal and choroidal detachment, and foreign bodies. CT and MR imaging are superior in evaluation of orbital disease. Color Doppler US often allows differential diagnosis of vascular, inflammatory, and neoplastic disease.

Orthotopic liver transplantation is currently the treatment of choice in patients with end-stage liver disease for which no other therapy is available. In children, segmental liver transplantation with living donor, reduced-size cadaveric, and split cadaveric allografts has become an important therapeutic option. However, the resulting expansion of the donor pool has increased the risk for postoperative vascular and biliary complications, which affect children more frequently than adults. Early recognition of these complications requires radiologic evaluation because their clinical manifestations are frequently nonspecific and vary widely. Doppler ultrasonography (US) plays the leading role in the postoperative evaluation of pediatric patients. Current magnetic resonance (MR) imaging techniques, including MR angiography and MR cholangiography, may provide a wealth of pertinent information and should be used when findings at US are inconclusive. Computed tomography is a valuable complement to US in the evaluation of complications involving the hepatic parenchyma as well as extrahepatic sites and is commonly used to guide percutaneous aspiration and fluid collection drainage. Familiarity with and early recognition of the imaging appearances of the various postoperative complications of pediatric liver transplantation are crucial for graft and patient survival.

The objective of our study was to determine the significance of mild hydronephrosis in newborns and infants as an indicator of vesicoureteral reflux (VUR). The voiding cystourethrography (VCUG) of 573 patients aged 0–18 months with mild, sonographically detected hydronephrosis were reviewed for VUR. Patients with secondary reflux or anomalies making an exact reflux grading impossible were excluded. Normal kidneys, contralateral to hydronephrotic ones, were included. Each kidney was considered separately, forming a total of 1,146 renal units. Mild hydronephrosis was defined as an anteroposterior diameter of the renal pelvis of 0.5–1.5 cm without caliectasis. The International Grading System was used to grade VUR. Seven hundred and thirty-six kidneys had mild hydronephrosis. VUR occurred in 189 out of 736 (25.7%) of these kidneys, and in 108 out of 410 (26.3%) non-distended kidneys, contralateral to hydronephrotic ones (p=0.806). No statistical differences in the frequency of VUR and dilatation were found between the subgroups of patients with and without infection, except for a higher grade of reflux in the group with infection. The frequency of VUR in mildly dilated kidneys was not significantly different from that in non-distended ones. There was a poor correlation between VUR and mild hydronephrosis. The latter should not be considered in itself an indication for VCUG in asymptomatic neonates and infants.

Congenital anomalies of the gastrointestinal tract are a significant cause of morbidity in children and, less frequently, in adults. These abnormalities include developmental obstructive defects of the small intestine, anomalies of the colon, anomalies of rotation and fixation, anorectal anomalies, and intestinal duplications. Neonates with complete high intestinal obstruction do not usually require further radiologic evaluation following radiography, whereas those with complete low obstruction should undergo a contrast material enema examination. An upper gastrointestinal series must be performed in all patients with incomplete intestinal obstruction because management is different in each case. In low intestinal obstruction, ultrasonography (US) may help differentiate between small bowel obstruction and colonic obstruction. In addition, US can help correctly identify meconium ileus and meconium peritonitis and is useful in the diagnosis of enteric duplication cysts. In malrotation and anorectal anomalies, computed tomography (CT) and magnetic resonance (MR) imaging can provide superb anatomic detail and added diagnostic specificity. Intestinal duplications manifest as an abdominal mass at radiography, contrast enema examination, or US. At CT, most duplications manifest as smoothly rounded, fluid-filled cysts or tubular structures with thin, slightly enhancing walls. At MR imaging, the intracystic fluid has heterogeneous signal intensity on T1-weighted images and homogeneous high signal intensity on T2-weighted images. Familiarity with these gastrointestinal abnormalities is essential for correct diagnosis and appropriate management.

The usefulness of sonography in evaluating the pancreas in infants and children is well known. Its usefulness is due to the optimal sonic window provided by the relative lack of fat tissue and the large left hepatic lobe in children. A wide spectrum of pancreatic pathologic conditions can be identified sonographically in children, including congenital abnormalities; inflammatory, cystic, pseudocystic, and neoplastic lesions in usual and unusual manifestations; rare processes such as nesidioblastosis and Schwachman-Diamond syndrome; and pancreatic involvement in systemic disease. Multiple pathologic processes can affect the pancreas focally or diffusely, making diagnosis difficult in some instances, since the pancreatic response is limited to changes in echogenicity and size independent of the cause. Sonography is rapid, accurate, and noninvasive and does not require patient sedation. It is the modality of choice for evaluating suspected pancreatic disease, since it allows not only direct visualization of the pancreas but also evaluation of adjacent organs.

FNAH is an inherited disease of unknown pathogenesis. By means of clearance techniques we have demonstrated that diminished renal plasma flow and increased renal vascular resistance may be primary pathogenic events in FNAH (1). Ultrasonography and two-dimension echo-color-doppler (2D ECD) are two methods that have been applied to the study of renal morphology and the intrarenal vascular bed, respectively. Sonography is routinely used for the study of kidney size (2). In addition, sonography allows the assessment of the parenchymal thickness and the cortico-medular echogenicity (3). Twodimensional ultrasound imaging and blood flow detection with color doppler are accepted methods to quantify intrarenal vascular resistance (4). In this study we have examined renal morphology and the intrarenal vascular bed in patients with FNAH.