Intracranial germ cell tumors in children: an immunohistochemical and electron microscopic study

From a review of a series of 1,474 intracranial tumors occurring in children, we identified 49 patients (3.3%) with primary intracranial germ cell tumors: 65% germinomatous, 26% nongerminomatous (8 teratomas, 3 endodermal sinus, and 2 choriocarcinomas), and 8 degrees 10 mixed. Placental alkaline phosphatase was present in all germinomas tested. Human chorionic gonadotropin was identified in 7 patients, cytokeratin in 6, and alpha-fetoprotein in 4. The results of immunostaining with antisera against glial fibrillary acidic protein, desmin, and vimentin were essentially negative. Electron microscopy played an important role in confirming the diagnosis in patients with endodermal sinus and mixed tumors. The correct identification of mixed and non-germ-cell tumors requires adequate tumor sampling and proper preparation of tissue for immunohistochemical and electron microscopic examination.     

Pediatric sedation for procedures titrated to a desired degree of immobility results in unpredictable depth of sedation.

OBJECTIVE: To test the hypothesis that the need to attain immobility during pediatric sedation for procedures determines the depth of sedation, which cannot always be predicted. DESIGN: A retrospective review of sedation documents of 301 consecutive sedations of pediatric patients undergoing various procedures SETTING: Division of Critical Care sedation service within a children's hospital. MEASUREMENTS AND MAIN RESULTS: The medical records and sedation forms of our most recent 301 consecutive sedations were retrospectively reviewed. Based on the data gathered, the patients were categorized according to their achieved level of immobility, their level of consciousness according to the definitions of the American Academy of Pediatrics, the procedures for which sedation was administered, and the sedatives used. A total of 125 males and 89 females received 301 sedations. Their ages ranged from 22 days to 29 years (mean 7 y + 6 y). We recognized four categories of immobility for procedures. In category 1, some motion was allowed during painless and noninvasive procedures to the extent that it did not risk the patient nor hinder the successful performance of the procedures. In category 2, the patients were kept motionless during painless and noninvasive procedures. In category 3, the patients were kept motionless during painful and invasive procedures with the addition of local anesthetic. In category 4, the patients remained motionless throughout their painful or invasive procedure without the use of local anesthetics. There were 32, 10, 156 and 103 sedations in each category, respectively. Conscious sedation (CS) was observed in six sedations (19%) in category 1 of immobility; it was observed in none (0%) in category 2, in 4 sedations (2.6%) in category 3, and in 1 sedation (1%) in category 4. Deep sedation (DS) was noted in 26 category 1 sedations (81%), in 10 category 2 sedations (100%), in 136 category 3 sedations (87%), and in 63 category 4 sedations (61%). General anesthesia (GA) was only observed in categories 3 and 4 in 16 sedations (10%) and 39 sedations (38%), respectively. Intravenous (IV) ketamine, as a single agent or in combination with other agents, was the most frequently used sedative (88%) followed by IV benzodiazepines (64%), propofol (39%), opiates (15%), and barbiturates (5%). A total of 59 (19%) adverse events were encountered during the 301 sedations. In categories 1 and 2, no adverse event (0%) was encountered. In category 3, 19 adverse events took place (32%), and 40 adverse events (68%) (P< 0.05) occurred in category 4. CONCLUSIONS: Pediatric sedation results in 4 categories of immobility. Complete immobility during painful and invasive procedures is associated with a higher incidence of adverse events. The depth of sedation (ie, CS, DS, or GA) required to achieve each category of immobility is unpredictable and varies from patient to patient. Thus, granting a limited sedation authority (conscious sedation only) to physicians may be of limited practical value.     

Zur Bedeutung der Selenversorgung

Zusammenfassung Selenmangel führt bei Tier und Mensch zu seltenen, in der Schweiz unbekannten Krankheiten. Epidemiologisch besteht eine negative Korrelation zwischen Selenzufuhr und dem Auftreten bestimmter Karzinome, möglicherweise auch mit kardiovaskulären Erkrankungen. Ob der Zellschutz durch die selenabhängige Glutathionperoxydase der entscheidende pathogenetische Mechanismus ist, ist unbekannt. Die Selenversorung der Schweiz ist unvollständig untersucht. Die Selenzufuhr scheint an der unteren Grenze der RDA zu liegen, ist aber kein Grund zu genereller oder gezielter Selensubstitution.

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Selenium supply in Switzerland

Summary Selenium deficiency leads in animal and man to rare diseases, which are unknown in Switzerland. Epidemiologically there is a negative correlation between selenium intake and the incidence of certain cancers, possibly also with cardiovascular mortality. It is unknown whether the antioxidative protection by the selenium-containing enzyme glutathion-peroxidase is the only and decisive pathogenetic mechanism. The selenium supply in Switzerland is only partially investigated. It seems to be on the lower limit of the RDA, but does not justify increased selenium intake generally or in potential risk groups.

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L'importance de l'apport en sélénium

Résumé Le déficit en sélénium conduit chez l'animal et chez l'homme à des maladies rares, inconnues en Suisse. Des travaux épidémiologiques mettent en évidence une relation négative entre l'apport en sélénium et l'apparition de certains cancers et peut-Être de maladies cardiovasculaires. Le mécanisme pathogénique pourrait impliquer le rÔle de l'enzyme glutathion-peroxidaire, dépendante du sélénium, dans la protection cellulaire, mais reste en fait inconnu. L'apport en sélénium n'est qu'incomplètement documenté en Suisse. Il semble se situer à la limite inférieure de l'apport abservé en RDA, mais ne justifie cependant pas une supplémentation, ni généralisée ni dans des groupes particuliers.

     

Analysis of the receptor involved in the central hypotensive effect of rilmenidine and moxonidine

The aim of this study was to determine whether α₂-adrenoceptors or imidazoline I₁-receptors are responsible for the central sympathoinhibition produced by rilmenidine and moxonidine, two clonidine-like antihypertensive drugs. Rilmenidine and moxonidine were compared with the indirectly acting α₂-adrenoceptor agonist α-methyldopa. Three antagonists were used. Yohimbine and SK & F86466 were used as selective α₂-adrenoceptor antagonists. They were compared with efaroxan which is also an α₂-adrenoceptor antagonist, but, in addition, possesses affinity for imidazoline I₁-receptors. According to some but not all studies, the affinity of efaroxan for I₁-receptors is much higher than its affinity for α₂-adrenoceptors. Drugs were administered into the cisterna cerebellomedullaris of conscious rabbits by a catheter implanted previously under halothane anaesthesia. Rilmenidine (10 μg kg^–1), moxonidine (0.3 μg kg^–1) and α-methyldopa (0.4 mg kg^–1) lowered blood pressure and the plasma noradrenaline concentration; the degree of sympathoinhibition produced by the three agonists was very similar. When injected after the agonists, efaroxan (0.1–14 μg kg^–1; cumulative doses), yohimbine (0.4–14 μg kg^–1) and SK & F86466 (0.4–44 μg kg^–1) counteracted the effects of the agonists on blood pressure and the plasma noradrenaline concentration. Efaroxan was about tenfold more potent than yohimbine and SK & F86466 at antagonizing the hypotensive effects of α-methyldopa. Similarly, efaroxan was two- to tenfold more potent than yohimbine and SK & F86466 against rilmenidine and moxonidine. Finally, efaroxan was about as potent against α-methyldopa as against rilmenidine and moxonidine. The results confirm previous observations that selective α₂-adrenoceptor antagonists are capable of completely antagonizing effects of rilmenidine and moxonidine. The effects of the α₂-adrenoceptor antagonist with an additional high affinity for imidazoline I₁-receptors, efaroxan, can also be explained by blockade of α₂-adrenoceptors. Efaroxan was more potent against rilmenidine and moxonidine than the selective α₂-adrenoceptor antagonists. This was probably due to the fact that the affinity of efaroxan for α₂-adrenoceptors is higher than the affinity of yohimbine and SK & F86466, since efaroxan was also the most potent of the three antagonists against the indirectly acting α₂-adrenoceptor agonist α-methyldopa. The observation that efaroxan was equally potent against rilmenidine and moxonidine and against α-methyldopa suggests that the same receptors were involved in the effects of the three agonists, α₂-adrenoceptors; this observation is not compatible with the high I₁/α₂ selectivity of efaroxan and the hypothesis that rilmenidine and moxonidine activate I₁-receptors, whereas α-methyldopa activates α₂-adrenoceptors. Thus, the data do not indicate involvement of I₁ imidazoline receptors in the central sympathoinhibition elicited by ril-menidine and moxonidine in rabbits. It is likely that ril-menidine and moxonidine produce sympathoinhibition by activating the same receptors which are activated by the indirectly acting catecholamine α-methyldopa, namely α₂-adrenoceptors. Received: 7 December 1998 / Accepted: 2 February 1999     

Tuberculosis in the inner city: impact of a continuing epidemic in the 1990s.

Tuberculosis cases have recently declined in the United States, renewing interest in disease elimination. We examined the epidemiology of tuberculosis from 1991 through 1997 at an inner-city public hospital and assessed population-based tuberculosis rates by ZIP code in the 8 metropolitan Atlanta counties. During the 7 years, 1378 new patients had tuberculosis diagnosed at our hospital (mean, 197 patients/year), accounting for 25% of tuberculosis cases in Georgia. Coinfection with human immunodeficiency virus (HIV) was common, but a significant decrease in the proportion of HIV-infected patients with tuberculosis was noted over time. Most patients were members of a minority group (93%) and were born in the United States (96%). Two inner-city ZIP code areas had annual tuberculosis rates >120 cases per 100,000 persons, and 8 ZIP code areas had annual rates of 47-88 cases per 100,000 persons between 1993 and 1997, compared with the annual national average of 8.7 cases per 100,000 persons. Our hospital continues to care for large numbers of tuberculosis patients, and rates of tuberculosis remain high in the inner city. These data mandate a concentration of efforts and resources in urban locations if tuberculosis control and elimination is to be achieved in the United States.     

Effect and Toxicity of Endoluminal High-Dose-Rate (HDR) Brachytherapy in Centrally Located Tumors of the Upper Respiratory Tract

Aim: To assess effect and toxicity of high-dose-rate afterloading (HDR) alone or in combination with external beam radiotherapy (EBRT) in centrally located tumors of the upper respiratory tract. Patients and Methods: From 1987 to 1996, 55 patients were treated. Twenty-one patients (group A1: 17 non-small-cell lung cancer [NSCLC], A2: 4 metastases from other malignancies) were treated using HDR alone due to a relapse after external beam irradiation. In 34 previously untreated and inoperable patients (group B1: 27 NSCLC, B2: 7 metastases from other malignancies) HDR was given as a boost after EBRT (30 to 60 Gy, median 50). HDR was carried out with a ¹⁹²Ir source (370 GBq). The brachytherapy dose (group A: 5 to 27 Gy, median 20; B: 10 to 20 Gy, median 15) was prescribed to 1 cm distance from the source axis. A distanciable applicator was used in 39/55 patients. Results: In group A1, a response rate (CR, PR) of 53% (group B1: 77%) was reached. The median survival (Kaplan-Meier) was 5 months in group A1 (B1: 20 months). The 1-, 3- and 5-year local progression free survival rates (Kaplan-Meier) were 66% (15%), 52% (0%), and 37% (0%) in group B1 (group A1). Prognostic favorable factors in group B1 were a tumor diameter < 20 mm, the lack of radiological mediastinal involvement, a complete remission, and a Karnofsky performance status > 70. Grade-1 or 2 toxicity (RTOG/EORTC) occurred in 0% in group A and in 6% in group B. We observed no Grade-3 or 4 toxicity. Complications caused by persistent or progressive local disease occurred in 3 patients in group A (fatal hemorrhage, tracheomediastinal fistula, hemoptysis) and in 2 patients in group B (fatal hemorrhage, hemoptysis). Conclusions: HDR brachytherapy is an effective treatment with moderate side effects. In combination with external beam irradiation long-term remissions can be reached in one third of the patients. Ziel: Evaluierung von Effektivität und Toxizität der endoluminalen High-dose-rate-(HDR-)Brachytherapie als alleinige oder kombinierte (EBRT) Therapie bei zentral sitzenden Tumoren der oberen Atemwege. Patienten und Methode: Von 1987 bis 1996 wurden 55 Patienten behandelt. 21 Patienten (Gruppe A1: 17 Patienten mit nichtkleinzelligem Bronchialkarzinom [NSCLC], A2: vier Patienten mit Metastasen anderer Tumoren) wurden bei Lokalrezidiven nach vorheriger perkutaner Bestrahlung ausschließlich endoluminal bestrahlt. Bei 34 inoperablen und vorher unbehandelten Patienten (Gruppe B1: 27 NSCLC, B2: sieben Metastasen anderer Tumoren) wurde die Brachytheranie als Boost nach externer Bestrahlung (30 bis 60 Gy, Median 50) appliziert. Die endoluminale Bestrahlung wurde mit einer ¹⁹²Ir-Quelle (370 GBq) durchgeführt. Dosiert wurde auf 1 cm Quellenabstand (Gruppe A: 5 bis 27 Gy, Median 20; B: 10 bis 20 Gy, Median 15). Ein distanzierbarer Spreizkorbapplikator wurde bei 39/55 Patienten verwendet. Ergebnisse: In Gruppe A1 wurde ein Therapieansprechen (CR, PR) in 53% erzielt (Gruppe B1: 77%). Das mediane Überleben (Kaplan-Meier) betrug fünf Monate in Gruppe A1 (B1: 20 Monate). Das lokalrezidivfreie Ein-, Drei- und Füf-Jahres-Überleben (Kaplan-Meier) betrug in Gruppe B1 ((A1) 66% (15%), 52% (0%) und 37% (0%). Als prognostisch günstige Faktoren konnten in Gruppe B1 ein Tumordurchmesser < 20 mm, radiologisch fehlende mediastinale Beteiligung, eine komplette Remission und ein Karnofsky-Index > 70 ermittelt werden. Grad-1- oder -2-Toxizität (RTOG/EORTC) trat in keinem Fall in Gruppe A und in 6% in Gruppe B auf. Wir beobachteten keine Grad-3- oder -4-Toxizität Tumorassoziierte Komplikationen kamen in drei Fällen in Gruppe A (Blutung, tracheomediastinale Fistelung, Hämoptysen) und in zwei Fällen in Gruppe B vor (Blutung, Hämoptysen). Schlußfolgerungen: Die endoluminale HDR-Brachytherapie ist eine effektive Therapie mit moderaten Nebenwirkungen. In Kombination mit externer Radiotherapie können Langzeitremissionen bei einem Drittel der Patienten erzielt werden.     

MR-Bildgebung der Nieren Neue Ans?tze in der Diagnostik* Neue Ans?tze in der Diagnostik*

Fragestellung: Darstellung neuer diagnostischer M?glichkeiten im Bereich der Niere mittels schneller Magnetresonanz (MR)- Bildgebung.