Archive of Medical Research

Pseudoparoxysms.

Tomcsányi J, Bózsik B.

[Uncommon case of paraganglioma syndrome in combination with malignant paraganglioma]

BACKGROUND: Combination of paraganglioma syndrome and malignant paraganglioma is an uncommon disease worldwide. PATIENT: We report the case of a 69-year old man with a jugular-tympanal paraganglioma, who underwent surgery. Histopathological examination revealed a malignant paraganglioma. An other contralateral carotid-body and a tumor in the thyroid gland had been discovered during staging. The molecular results confirmed the existence of a paraganglioma syndrome. DISCUSSION: A malignant paraganglioma based on a hereditary paraganglioma syndrome is a rare described case in literature. On the background of the literature we discuss the pathology, pathogenesis, diagnostic and therapy of this disease.

Schmahl K, Atamna N, Schönijahn T, Lülsdorf P, Göller T, Jacob R.

Abt. XIII, Pathologie, Bundeswehrzentralkrankenhaus Koblenz.

[Obstructive sleep apnea in patients with Parkinson\’s disease–report of two cases and review]

BACKGROUND: The use of continuous positive airway pressure (CPAP) is well established in treatment of moderate and severe obstructive sleep apnea syndrome (OSAS). The judgement of clinical symptoms like daytime sleepiness and hypersomnolence with loss in concentration is complicated in patients with diagnosis of Morbus Parkinson (MP) because the disease itself and pharmacologic therapy may mimic clinical features of OSAS. PATIENTS AND METHODS: Diagnostic pathways and differential diagnostic considerations are demonstrated in two case reports of patients with MP and OSAS. The cases are discussed within the framework of literature concerning sleep disturbances and MP. RESULTS: In both cases respiration could be treated effectively by continuous positive airway pressure (CPAP). Patients clearly responded to therapy and regained more daytime activity. The medication for MP was satisfactory. CONCLUSIONS: The evaluation and treatment of daytime sleepiness in patients with MP and obstructive sleep apnea need an interdisciplinary framework with a practitioner, a neurologist, and a sleep expert. Associated symptoms as increased nycturia, hypokinesia, restless-leg-symptoms, and depression as well as the effects of medication may mimic details of concomitant sleep apnea. Therefore, sleep diagnostic evaluation is recommended to rule out sleep apnea as a frequent cause for hypersomnolence.

Steffen A, Hagenah J, Graefe H, Mahlerwein M, Wollenberg B.

Klinik und Poliklinik für Hals-, Nasen- und Ohrenheilkunde der Universität zu Lübeck, Lübeck . armin.steffen@uk-sh.de

Fast-recovery fast spin-echo T2-weighted MR imaging: a free-breathing alternative to fast spin-echo in the pediatric abdomen.

In the mid 1990s, the fast spin-echo (FSE) and turbo spin-echo (TSE) T2-weighted (T2-W) sequences became available and are now widely accepted alternatives to conventional spin-echo sequences since they result in reduced acquisition times while maintaining tissue contrast. Since that time, there has been continued development of new sequences to further decrease acquisition times, minimize artifacts, and preserve lesion detection. The purpose of this pictorial essay is to qualitatively illustrate the newly available fast recovery (FR) FSE T2-W MR images of the abdomen compared with the images acquired using the routine FSE T2-W sequence in non-breath-hold studies in children.

Huang IH, Emery KH, Laor T, Valentine M, Tiefermann J.

Department of Radiology, Cincinnati Children’s Hospital Medical Center, 3333 Burnet Avenue, Cincinnati, OH, 45229-3039, USA.

Catheters, wires, tubes and drains on postoperative radiographs of pediatric cardiac patients: the whys and wherefores.

Surgical treatment of congenital heart disease has advanced dramatically since the first intracardiac repairs in the mid-20th century. Previously inoperable lesions have become the focus of routine surgery and patients are managed successfully in intensive care units around the world. As a result, increasing numbers of postoperative images are processed by departments of radiology in children\’s hospitals. It is important that the radiologist accurately documents and describes the catheters, wires, tubes and drains that are present on the chest radiograph. This article reviews the reasons for the placement and positioning of perioperative equipment in children who have surgical repair of atrial septal defect, ventricular septal defect or transposition of the great arteries. Also included are a brief synopsis of each cardiac anomaly, the surgical procedure for its correction, and an in-depth discussion of the postoperative chest radiograph including illustrations of catheters, wires, tubes and drains.

Teele SA, Emani SM, Thiagarajan RR, Teele RL.

Department of Cardiology, Children’s Hospital Boston, 300 Longwood Ave., Boston, 02115, MA, USA, sarah.teele@cardio.chboston.org.

Partial tear of the quadriceps tendon in a child.

We present a case of partial rupture of the quadriceps tendon in an 8-year-old girl. This is one of the youngest patients reported with a quadriceps tendon rupture, an entity seen predominantly in middle-aged people. The strength of the muscle tendon unit in a child makes tendon injuries extremely unusual as compared to apophyseal avulsions. The MR imaging findings of this unusual pediatric injury are illustrated.

Khanna G, El-Khoury G.

Department of Radiology, University of Iowa Hospitals and Clinics, 200 Hawkins Drive, Iowa City, IA, 52242, USA, geetika-khanna@uiowa.edu.

CT and MR imaging in atypical teratoid/rhabdoid tumors of the central nervous system.

INTRODUCTION: Atypical teratoid/rhabdoid tumors (ATRT) are rare aggressive neoplasms of the CNS affecting predominantly very young children. METHODS: We retrospectively reviewed the imaging findings of 9 CT and 32 MR examinations of the brain and spine of 33 children. RESULTS: Of the 33 tumors, 11 were located in the infratentorial compartment, 16 in the supratentorial compartment, 5 in both cranial compartments, and 1 in the lower thoracic spinal cord. The mean age of the children with infratentorial or infra- and supratentorial tumors was significantly lower than the mean age of the children with purely supratentorial tumors. Heterogeneity on imaging, large size and high tumor stages are striking features reflecting the aggressive nature of this histopathological entity. Although not present in the majority of children, a distinct and unusual pattern of a wavy band-like enhancement surrounding a central hypointensity was present in 12 of 32 children (38%) in whom contrast medium was used. CONCLUSION: To the best of our knowledge this is the largest number of imaging examinations of ATRTs so far reported. A rather unusual pattern of contrast enhancement may be typical of ATRTs.

Warmuth-Metz M, Bison B, Dannemann-Stern E, Kortmann R, Rutkowski S, Pietsch T.

Reference Centre for Neuroradiology of the German Society for Pediatric Hematology and Oncology (GPOH), Department of Neuroradiology, University of Würzburg, Würzburg, Germany, warmuth@neuroradiologie.uni-wuerzburg.de.

Expanding the scope of MS binding assays to low-affinity markers as exemplified for mGAT1.

Following a recently developed concept of MS binding assays based on the quantification of a native marker by LC-MS a procedure to study binding of a low-affinity marker in kinetic, saturation, and competition experiments was established. Separation of bound and unbound marker-the most crucial step of the assay-could be effectively achieved by filtration in a 96-well-format. MS binding assays according to this procedure allowed the reliable characterization of NO 711 binding to mGAT1 in presence of physiological NaCl concentrations. Comparing the results obtained in the present study with those from experiments using 1 mol L(-1) NaCl in the incubation milieu reveals remarkable differences with respect to the marker\’s affinity and kinetics and to the investigated test compound\’s potency.

Zepperitz C, Höfner G, Wanner KT.

RCC Ltd, Zelgliweg 1, 4452, Itingen, Switzerland.

High-performance liquid chromatography-tandem mass spectrometry in the identification and determination of phase I and phase II drug metabolites.

Applications of tandem mass spectrometry (MS/MS) techniques coupled with high-performance liquid chromatography (HPLC) in the identification and determination of phase I and phase II drug metabolites are reviewed with an emphasis on recent papers published predominantly within the last 6 years (2002-2007) reporting the employment of atmospheric pressure ionization techniques as the most promising approach for a sensitive detection, positive identification and quantitation of metabolites in complex biological matrices. This review is devoted to in vitro and in vivo drug biotransformation in humans and animals. The first step preceding an HPLC-MS bioanalysis consists in the choice of suitable sample preparation procedures (biomatrix sampling, homogenization, internal standard addition, deproteination, centrifugation, extraction). The subsequent step is the right optimization of chromatographic conditions providing the required separation selectivity, analysis time and also good compatibility with the MS detection. This is usually not accessible without the employment of the parent drug and synthesized or isolated chemical standards of expected phase I and sometimes also phase II metabolites. The incorporation of additional detectors (photodiode-array UV, fluorescence, polarimetric and others) between the HPLC and MS instruments can result in valuable analytical information supplementing MS results. The relation among the structural changes caused by metabolic reactions and corresponding shifts in the retention behavior in reversed-phase systems is discussed as supporting information for identification of the metabolite. The first and basic step in the interpretation of mass spectra is always the molecular weight (MW) determination based on the presence of protonated molecules [M+H](+) and sometimes adducts with ammonium or alkali-metal ions, observed in the positive-ion full-scan mass spectra. The MW determination can be confirmed by the [M-H](-) ion for metabolites providing a signal in negative-ion mass spectra. MS/MS is a worthy tool for further structural characterization because of the occurrence of characteristic fragment ions, either MS( n ) analysis for studying the fragmentation patterns using trap-based analyzers or high mass accuracy measurements for elemental composition determination using time of flight based or Fourier transform mass analyzers. The correlation between typical functional groups found in phase I and phase II drug metabolites and corresponding neutral losses is generalized and illustrated for selected examples. The choice of a suitable ionization technique and polarity mode in relation to the metabolite structure is discussed as well.

Holčapek M, Kolářová L, Nobilis M.

Department of Analytical Chemistry, Faculty of Chemical Technology, University of Pardubice, Nám. Čs. Legií 565, 53210, Pardubice, Czech Republic, michal.holcapek@upce.cz.

Thermal desorption characterisation of molecularly imprinted polymers. Part I: a novel study using direct-probe GC-MS analysis.

A novel thermal desorption technique using a direct-probe device (Chromatoprobe) attached to a gas chromatograph-mass spectrometer is presented for the thermal pretreatment, characterisation and analysis of molecularly imprinted polymers. The technique is demonstrated as effective for the removal of volatile materials, including template and unreacted monomers, from methacrylic acid-ethylene glycol dimethacrylate copolymers imprinted with 2-aminopyridine. Mass spectrometry is a powerful technique for polymer bleed characterisation. Thermal desorption studies on reloaded template and related compounds are reported as a means of assessing polymer morphology, specific binding by imprinted polymers compared with reference non-imprinted polymers and selective binding by an imprinted polymer for its template. Calibration studies on the thermal desorption technique using an internal standard are presented with R (2) > 0.999. The technique provides a novel method for assessment of polymer thermal stability, composition and morphology.

Cummins W, Duggan P, McLoughlin P.

Separation Science Research Group, Department of Chemical and Life Sciences, Waterford Institute of Technology, Cork Road, Waterford, Ireland.