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Diagnostic work-up and major treatment strategies of five pediatric solid tumors, namely neuroblastoma, rhabdomyosarcoma, nephroblastoma, Ewing's tumor and choroid plexus carcinoma, are brifly reported by a case study approach.

The hybrid technique of PET/CT has significantly impacted the imaging and management of head and neck squamous cell cancer (HNSCC) since its introduction and has become the technique of choice for imaging of this cancer. Diagnostic FDG PET/CT is useful for identification of an unknown primary tumor, delineation of extent of primary tumor, detection of regional lymph node involvement even in a normal-sized node, detection of distant metastases and occasional synchronous primary tumor, assessment of therapy response, and long-term surveillance for recurrence and metastases. The role of PET/CT is evolving in radiation therapy planning. Combined diagnostic PET/CT provides the best anatomic and metabolic in vivo information for the comprehensive management of HNSCC. FDG PET/CT is the modality of choice in detecting metastasis of differentiated thyroid cancer, when the disease is iodine negative. It is valuable in staging and prognosis of anaplastic and medullary thyroid cancer.

Ion implantation was used to fabricate ultra-thin nanocomposite subsurface layers in inert polymers for applications in mechanics, optics and electronics [1]. Amorphous polycarbonate substrates were implanted at room temperature with low energy Cu+ ions of 60 keV, at 1 μA/cm2 and with doses in a range from 1×1016 to 1×1017 ions/cm2. The nanocomposite surfaces were investigated by transmission electron microscopy (TEM), X-ray diffraction (XRD), optical absorption spectroscopy and electrical conductivity. Cross-section transmission electron microscopy (XTEM) was used to analyze the microstructure and morphology of the Cu-implanted region. TEM experiments show that nanocrystals are formed at ion doses of 1×1016 ions/cm2 (Figure1). The ionimplanted nanocrystals are located at about 50nm–80nm below the polymer surface, in accordance with TRIM calculations (projected range of 75nm and straggling of 20nm). However, at higher ion doses (5×1016 ions/cm2) a continuous thin nanocrystalline copper films is produced. Figure 2 (b) shows the grazing-incidence XRD patterns (incidence angle = 1°) recorded prior and after Cu-implantation in polycarbonate as well as the corresponding diffraction difference curve. The observed diffraction peaks correspond to copper (cubic phase) in accordance with the ICDD (card no. 851326; JCPDS-ICDD 2000). The XTEM image (Figure 2a) shows a continuous polycrystalline copper films below the polycarbonate surface; the lattice fringes are well observed in the Cu film. Optical absorption spectra show a surface plasmon resonance at 2eV suggesting the formation of nanocrystalline Cu films. This characteristic SPR peak is well pronounced for doses of 5×1016 ions/cm2, while at higher doses the SPR peak is smeared out.

Gastroesophageal fundoplication can actually be considered one of the most common operations performed by pediatric surgeons on infants and children [5,15].

Laparoscopic antireflux surgery (LARS) in adults has semmingly replaced the open approached worldwide (6,11, 12,63]. Findings show it to be an established treatment option for chronic gastroesophageal reflux disease, with an excellent clinical outcome and success rates ranging between 90% and 100% [6].

Understanding the pathophysiology of gastroesophageal reflux (GER) is important in choosing the best diagnostic and therapeutic approach to adopt in children with GER [1, 9, 20]. GER is due to multiple factors which result in incompetence of the esophageal cardia, and allow reflux of gastric content into the esophagus. Competence of the esophageal cardia is due to both anatomical and physiological factors which form an antireflux barrier. GER is associated with the failure of these mechanisms against reflux [3, 6, 4, 15, 17, 19, 41, 44].

Recently, progress has been made in our understanding of the biochemical mechanisms that lead to vascular complications in diabetes and aging (Brownlee and Cerami 1984). Accumulation of advanced glycosylation end products (AGEs) in vascular tissue correlates closely with the development of vascular complications (Brownlee 1988). AGEs are formed as a late irreversible product of nonenzymatic glycosylation, and are characterized by their fluorescence, yellow-brown color and propensity to form crosslinks with other proteins and nucleic acids (Brownlee 1984). The AGEs arise from earlier glycosylation products, such as the Amadori products, through an as yet to be defined series of further reactions and rearrangements (Brownlee 1988; Monnier 1984; Brownlee 1984; Brownlee 1987).

Regulation of vascular permeability and the coagulation mechanism are two central properties of the endothelium (Gimbrone 1986). The presence of multiple active mechanisms through which endothelial cells contribute to the maintenance of barrier function and fluidity of blood has been demonstrated, suggesting that endothelial regulation of vascular homeostasis occurs in response to environmental stimuli.