Predictive chromosomal clusters of synchronous and metachronous brain metastases in clear cell renal cell carcinoma

Synchronous (early) and metachronous (late) brain metastasis (BM) events of sporadic clear cell renal cell carcinoma (ccRCC) (n = 148) were retrospectively analyzed using comparative genomic hybridization (CGH). Using oncogenetic tree models and cluster analyses, chromosomal imbalances related to recurrence-free survival until BM (RFS-BM) were analyzed. Losses at 9p and 9q appeared to be hallmarks of metachronous BM events, whereas an absence of detectable chromosomal changes at 3p was often associated with synchronous BM events. Correspondingly, k-means clustering showed that cluster 1 cases generally exhibited low copy number chromosomal changes that did not involve 3p. Cluster 2 cases had a high occurrence of -9p/-9q (94-98%) deletions, whereas cluster 3 cases had a higher frequency of copy number changes, including loss at chromosome 14 (80%). The higher number of synchronous cases in cluster 1 was also associated with a significantly shorter RFS-BM compared with clusters 2 and 3 (P = 0.02). Conversely, a significantly longer RFS-BM was observed for cluster 2 versus clusters 1 and 3 (P = 0.02). Taken together, these data suggest that metachronous BM events of ccRCC are characterized by loss of chromosome 9, whereas synchronous BM events may form independently of detectable genetic changes at chromosomes 9 and 3p.

Mucoepidermoid carcinoma of the lung in a 6-year-old boy

Primary malignant lung tumours, especially the mucoepidermoid cancer of the bronchus, are very uncommon in childhood. Obtaining the diagnosis might be difficult due to unspecific initial symptoms but early detection and treatment is crucial for a good long-term survival. Bronchoscopy is considered the "gold standard" for making the diagnosis. The recommended therapy for a mucoepidermoid lung cancer is sleeve lobectomy with favourable overall survival after complete resection. We report the case of a 6-year-old boy with a right-upper-lobe bronchus tumour. The histological examination revealed a low-grade mucoepidermoid carcinoma.

Effects of rifampicin, dexamethasone, St. John's Wort and Thyroxine on maternal and foetal expression of Abcb1 and organ distribution of talinolol in pregnant rats

It is well accepted that ABCB1 plays a critical role in absorption, distribution and elimination of many xenobiotics and drugs. Only little is known about the regulation and function of ABCB1 during pregnancy. Thus, the aim of this study is to investigate maternal, placental and foetal Abcb1 expression and function in pregnant rats after induction with rifampicin, dexamethasone, St. John's wort (SJW) or thyroxine. Wistar rats were orally treated with rifampicin (250 mg/kg), SJW (1.0 g/kg), thyroxine (9 μg/kg), dexamethasone (1 mg/kg) or 0.5% methylcellulose suspension (control) for 9 days during late pregnancy (each N = 5). Afterwards, organ mRNA expression and protein content of Abcb1a were determined. Tissue concentrations of the ABCB1 probe drug talinolol were measured after repeated administration of the drug (100 mg/kg, 9 days) and after induction with oral rifampicin (250 mg/kg, 9 days, N = 5). Abcb1 expression was substantially lower in foetal than in maternal organs. Abcb1 was significantly induced by SJW in the maternal jejunum and placenta, by dexamethasone in foetal brain and liver and by thyroxine in the placenta and maternal and foetal brain. Rifampicin induced Abcb1 in all maternal and foetal organs. However, organ distribution of talinolol was not influenced by comedication of rifampicin. In conclusion, maternal and foetal Abcb1 organ expression in pregnant rats is inducible by nuclear receptor agonists. Although rifampicin regulates maternal and foetal Abcb1 expression, organ distribution of talinolol remains unchanged most likely caused by the known inhibitory effect of rifampicin on Abcb1 function.

Ultrastructure of Human Placental Tissue After 6h of Normoxic and Hypoxic Dual In Vitro Placental Perfusion

The dual in vitro perfusion model of human placental tissue allows the study of different aspects of placental function, such as metabolism, transport and secretion of proteohormones, cytokines and prostaglandins. The integrity of the perfused placental tissue is an important parameter to validate the perfusion system. Using light and electron microscopy, the morphology of villous tissue was examined before and after six hours of normoxic (n=10) vs. hypoxic (n=10) perfusion. An apical shift of the rough endoplasmic reticulum and occasional vacuoles were found in the syncytiotrophoblast of the terminal villi, the exchange area of the placenta. No unexpected pathological findings were seen before the perfusion experiments and only slight changes with moderate distension of the endoplasmic reticulum after 6 h of normoxic perfusion. After hypoxic perfusions, distinct ultrastructural alterations, such as oedematous villous stroma, swollen or completely destroyed cell organelles (e.g., mitochondria and endoplasmic reticulum), multiple vacuoles inside syncytio- and cytotrophoblasts as well as the microvilli were seen, which leads to an impairment of the placental barrier and other functions. The ultrastructural examination of placental tissue before and after dual in vitro perfusion broadens the knowledge of physiological and pathophysiological processes in the perfused placenta and may be a beneficial part of regular validation.

Non-invasive quantification of hepatic fat fraction by fast 1.0, 1.5 and 3.0 T MR imaging

INTRODUCTION

Even mild hepatic steatosis in a split liver donor may cause general liver failure and death in the donor. So far, CT density measurements or percutaneous biopsy is used to determine the presence of hepatic steatosis. Magnetic resonance imaging (MRI) may be an elegant method of non-invasive and non-radiation quantification of hepatic fat content.

METHODS

Fast gradient echo (GRE) technique was used to discriminate between fat and water spins. Echo time (TE) was adjusted for field strength dependent in-phase and out-of-phase states at 1.0, 1.5 and 3.0 T. Continuous MR signal transition from 100% water to 100% fat was investigated using a wedge water-oil phantom, which was positioned in such a way, that no spatial resolution occurred, thereby combining water and fat in one slice.

RESULTS

Using the phantom, a significant difference for a 5% difference in fat content was demonstrated in the range from 20 to 80% fat content (p<0.05) for all tested field strengths. In 25 patients MRI data were correlated with the percentage of fat determined by histologic evaluation of a CT-guided liver biopsy. Using the linear correlation calculated from the MRI phantom data at 1.0 T, we determined the liver fat from each patient's MRI measurements. Comparison of these data with the histologic quantified fat fraction of liver tissue showed a strong correlation (r(2)=0.93 for TE 6 ms and r(2)=0.91 for TE 10 ms).

CONCLUSION

The described method can be used to determine the presence of hepatic steatosis of >10% with p<0.05.

Organic anion transporting polypeptide 2B1 is a high-affinity transporter for atorvastatin and is expressed in the human heart

BACKGROUND

The cardiac effects of statins are subject to controversial discussion, and the mechanism of their uptake into the human heart is unknown. A candidate protein is the organic anion transporting polypeptide (OATP) 2B1 (SLCO2B1), because related transporters are involved in the uptake of statins into the human liver. In this study we examine OATP2B1 expression in the human heart and describe statins as inhibitors and substrates of OATP2B1.

METHODS

The expression of OATP2B1 was analyzed in 46 human atrial and 15 ventricular samples, including samples from hearts with dilated cardiomyopathy and hearts with ischemic cardiomyopathy.

RESULTS

Significant messenger ribonucleic acid expression was found in all samples, with no difference in the diseased hearts. However, patients who had taken atorvastatin exhibit decreased OATP2B1 messenger ribonucleic acid expression compared with patients with no statin treatment. OATP2B1 protein was detected at approximately 85 kd in atrial samples, as well as ventricular samples, and could be localized to the vascular endothelium. Furthermore, estrone-3-sulfate transport into OATP2B1-overexpressing Madin-Darby canine kidney II cells was inhibited by various drugs, including atorvastatin, simvastatin, cerivastatin, glyburide (INN, glibenclamide), and gemfibrozil, with the most pronounced effect being found for atorvastatin (inhibition constant, 0.7 +/- 0.4 micromol/L). Whereas simvastatin (lactone) itself was not transported by OATP2B1, atorvastatin was identified as a high-affinity substrate for OATP2B1 (Michaelis-Menten constant, 0.2 micromol/L) by direct transport measurement via liquid chromatography-tandem mass spectrometry.

CONCLUSION

OATP2B1 is a high-affinity uptake transporter for atorvastatin and is expressed in the vascular endothelium of the human heart, suggesting its involvement in cardiac uptake of atorvastatin.

Cerebral beta-amyloid angiopathy in aged squirrel monkeys

Cerebral beta-amyloid angiopathy (CAA) is an age-related disorder of the brain vasculature that is involved in up to 20% of non-traumatic cerebral hemorrhage in humans. CAA is a risk factor for cognitive decline, and may exacerbate the dementia of Alzheimer's disease. Progress in discovering the cause and potential therapies for this disorder has been hindered by the paucity of animal models, particularly models of idiopathic CAA. The squirrel monkey (Saimiri spp) develops significant CAA in the natural course of aging. To evaluate the suitability of Saimiri as a model of human CAA, we studied the distribution and composition of Abeta subtypes in CAA and parenchymal (senile plaque) deposits in the brains of aged squirrel monkeys, as well as the relationship between vascular beta-amyloid deposition and comorbid vasculopathies that occur in aged humans. Our findings show that: 1) CAA consists ultrastructurally of classical amyloid fibrils and is the principal type of cerebral beta-amyloidosis in squirrel monkeys; 2) The two primary isoforms of Abeta (Abeta40 and Abeta42) coexist in most microvascular and parenchymal lesions of Saimiri, although Abeta40 tends to predominate in larger arterioles; 3) CAA and parenchymal plaques overlap to a considerable degree in most affected brain areas, and are distributed symmetrically in the two hemispheres; 4) Both CAA and plaques are particularly abundant in rostral regions and comparatively sparse in the occipital lobe; 5) Capillaries are especially vulnerable to CAA in squirrel monkeys; and 6) When CAA is severe, it is associated with a small, but significant, increase in other vasculopathies, including microhemorrhage, fibrinoid extravasation and focal gliosis. These findings, in the context of genetic, vascular and immunologic similarities between squirrel monkeys and humans, support the squirrel monkey as a biologically advantageous model for studying the basic biology of idiopathic, age-related CAA, and for testing emerging therapies for human beta-amyloidoses such as Alzheimer's disease.

3-Hydroxy-3-methylglutaryl coenzyme A reductase inhibitor Atorvastatin mediated effects depend on the activation status of target cells in PLP-EAE

The effect of Atorvastatin on transcriptional activity in murine experimental autoimmune encephalomyelitis (EAE) induced by PLP peptide 139-151 was analyzed by DNA microarray technique in lymph nodes and spinal cord at onset (10 days), height (20 days) and first remission (30 days) of disease. Fourteen genes were selectively influenced by Atorvastatin in EAE mice. They are mainly related to immune cell functions and regulation of cell-to-cell interaction. Interestingly, seven genes were also differentially regulated in CFA-injected control mice. But qualitative and quantitative differences to EAE mice argue for a dependency of statin effects on the activation status of target cells. Differential regulation of the newly detected candidate genes of statin effects COX-1 and HSP-105 and the previously known statin-responsive genes ICAM-1 and CD86 was confirmed by Western blot and immunohistochemistry. Flow cytometric analysis of lymph node cells revealed that the effect of Atorvastatin treatment in non-immunized healthy animals resembled the effect of immunization with PLP peptide regarding changes of T helper cells, activated B cells and macrophages. In EAE mice, these effects were partially reversed by Atorvastatin treatment. Monitoring of expression of the newly identified candidate genes and patterns of lymphocyte subpopulations might predict the responsiveness of multiple sclerosis patients to statin treatment.

Intestinal expression of P-glycoprotein (ABCB1), multidrug resistance associated protein 2 (ABCC2), and uridine diphosphate–glucuronosyltransferase 1A1 predicts the disposition and modulates the effects of the cholesterol absorption inhibitor ezetimibe in humans

BACKGROUND AND AIMS

Ezetimibe is an inhibitor of the cholesterol uptake transporter Niemann-Pick C1-like protein (NPC1L1). Target concentrations can be influenced by intestinal uridine diphosphate-glucuronosyltransferases (UGTs) and the efflux transporters P-glycoprotein (P-gp) (ABCB1) and multidrug resistance associated protein 2 (MRP2) (ABCC2). This study evaluates the contribution of these factors to the disposition and cholesterol-lowering effect of ezetimibe before and after induction of UGT1A1, P-gp, and MRP2 with rifampin (INN, rifampicin).

METHODS

Serum concentrations of ezetimibe, as well as its glucuronide, and the plant sterols campesterol and sitosterol (surrogate for cholesterol absorption) were studied in 12 healthy subjects before and after rifampin comedication. In parallel, duodenal expression of UGT1A1, P-gp, MRP2, and NPC1L1 was quantified by use of real-time reverse transcriptase-polymerase chain reaction and quantitative immunohistochemical evaluation. The affinity of ezetimibe and its glucuronide to P-gp and MRP2 was assessed in P-gp- overexpressing Madin-Darby canine kidney II cells and P-gp-containing or MRP2-containing inside-out vesicles.

RESULTS

Up-regulation of intestinal P-gp, MRP2, and UGT1A1 (but not of NPC1L1) by rifampin was associated with markedly decreased areas under the curve of ezetimibe and its glucuronide (116 +/- 78.1 ng.h/mL versus 49.9 +/- 31.0 ng.h/mL and 635 +/- 302 ng.h/mL versus 225 +/- 86.4 ng.h/mL, respectively; both P = .002) and increased intestinal clearances (2400 +/- 1560 mL/min versus 5500 +/- 4610 mL/min [P = .003] and 76.6 +/- 113 mL/min versus 316 +/- 457 mL/min [P = .010], respectively) and nearly abolished sterol-lowering effects. Intestinal expression of UGT1A1, ABCB1, and ABCC2 was inversely correlated with the effects of ezetimibe on plant sterol serum concentrations. Parallel in vitro studies confirmed that ezetimibe glucuronide is a high-affinity substrate of MRP2 and has a low affinity to P-gp whereas ezetimibe interacts with P-gp and MRP2.

CONCLUSIONS

The disposition and sterol-lowering effects of ezetimibe are modified by metabolic degradation of the drug via intestinal UGT1A1 and either intestinal or hepatic secretion (or both) via P-gp and MRP2.

Carbamazepine regulates intestinal P-glycoprotein and multidrug resistance protein MRP2 and influences disposition of talinolol in humans

BACKGROUND AND METHODS

The antiepileptic drug carbamazepine is known to be an inducer of cytochrome P450 (CYP) 3A4 after binding to the nuclear pregnane X receptor. To evaluate whether it also regulates the multidrug transporter proteins P-glycoprotein (P-gp) and multidrug resistance protein MRP2 in humans, duodenal expression of multidrug resistance gene MDR1 messenger ribonucleic acid (mRNA) and MRP2 mRNA, content of P-gp and MRP2, and disposition of the nonmetabolized P-gp substrate talinolol after intravenous (30 mg) and long-term oral administration (100 mg for 19 days) were assessed in 7 healthy subjects (age, 23-35 years; body weight, 64-93 kg) before and after comedication of carbamazepine (600 mg for 14-18 days).

RESULTS

Carbamazepine medication was associated with increased urinary excretion of D-glucaric acid and induction of carbamazepine elimination. Creatinine clearance was not affected. Duodenal expression of both MDR1 mRNA and MRP2 mRNA and the MPR2 protein was significantly induced, whereas the P-gp content was not affected. MDR1 mRNA expression and MPR2 mRNA expression were correlated ( r = 0.873, P <.001). After carbamazepine, metabolic clearance of intravenous talinolol was significantly increased. Residual clearance was significantly decreased in dependence on MDR1 mRNA expression ( r = -0.647, P =.012) and MRP2 mRNA expression ( r = -0.613, P =.020). Oral absorption of talinolol was significantly lower after carbamazepine comedication (53.2% +/- 15.5% versus 62.1% +/- 13.0%, P =.018), and renal clearance and metabolic clearance were significantly increased, correlated in each case with MDR1 mRNA ( r = 0.612, P =.020, and r = 0.554, P =.040, respectively) and MRP2 mRNA ( r = 0.596, P =.025, and r = 0.565, P =.035, respectively).

CONCLUSIONS

Aside from induction of CYP3A4, carbamazepine acts as an inducer of intestinal MDR1 mRNA, MRP2 mRNA, and MRP2 protein content.

Towards waterjet dissection in neurosurgery: experimental in-vivo results with two different nozzle types

Waterjet dissection is under close investigation as a new neurosurgical tool. Experimentally, a precise tissue dissection with vessel preservation has been demonstrated in the porcine cadaver brain. The safety of the device has been shown in first clinical applications. However, a detailed in-vivo analysis of the waterjet device is still awaited. In the present study, two often applied nozzle types (100 microm diameter emitting a coherent straight jet; 120 microm diameter emitting a helically rotating jet) were experimentally studied in vivo. Forty-one rabbits received a frontal waterjet corticotomy on either side with one nozzle type after microsurgical removal of the arachnoid membranes. Animals were sacrificed at 1, 3, 7 days and 6 weeks after surgery. Dissection morphology and vessel preservation were evaluated. Tissue trauma was analyzed by the extent of intra-operative haemorrhage, postsurgical oedema formation and astrocytic as well as microglial reactions. In all animals, reliable brain dissection was observed. Macroscopically, only minor bleeding occurred. Microscopically, also very precise brain dissection with both nozzle types was found. Vessels were preserved with both pressures applied (5 and 10 bar). Dissections with the 100 microm straight nozzle were more precise with respect to dissection margins. However, no significant difference in vessel preservation and extent of haemorrhage, oedema formation, astrocytic and microglial reactivity was shown. Malfunction defined as clotting of the instrument occurred only with the 100 microm nozzle. In four 100 microm straight nozzle hemispheres, even no brain dissection was seen. The results indicate that the waterjet enables very precise and reliable brain parenchyma dissection with minimal trauma and vessel preservation in vivo. If this can be proven to be of clinical relevance, the instrument will become a valuable neurosurgical tool. Based on these results, the authors selected the 120 microm Helix nozzle for further research with this device in the CNS.

CYP2D6 genotype and induction of intestinal drug transporters by rifampin predict presystemic clearance of carvedilol in healthy subjects

BACKGROUND

Clinical trials have indicated that the combined beta- and alpha-adrenergic receptor blocker carvedilol improves the survival rate in patients with advanced chronic heart failure. The objective of our study was the identification and quantification of factors that modulate steady-state serum concentrations of carvedilol and its enantiomers and that may influence therapeutic efficacy and safety.

METHODS

The influence of genetic variants of cytochrome P450 (CYP) 2D6 and CYP2C9 and of transporter proteins (P-glycoprotein, multidrug resistance protein 2 [MRP2]) on the disposition of carvedilol and its enantiomers after intravenous (5 mg) and long-term oral administration (25 mg for 7 days) was assessed in 12 healthy subjects. The intestinal expression of P-glycoprotein and MRP2 was analyzed by quantitative real-time polymerase chain reaction and immunohistochemical techniques.

RESULTS

The area under the serum concentration-time curve (AUC) values of carvedilol were significantly (P <.05) increased in 6 subjects with CYP2D6 deficiency, with effects being more pronounced for R(+)-carvedilol (230 +/- 72.6 ng. h/mL versus 93.9 +/- 64.6 ng. h/mL in extensive metabolizers) than for S(-)-carvedilol (62.9 +/- 21.1 ng. h/mL versus 32.7 +/- 14.5 ng. h/mL). The AUC and fecal excretion of intravenous carvedilol were correlated with the intestinal expression of MDR1 messenger ribonucleic acid (mRNA) (r = -0.67, P =.001; r = 0.83, P =.002) and MRP2 mRNA (r = -0.74, P <.001; r = 0.70, P =.025). Furthermore, we measured the disposition of long-term oral carvedilol after comedication of the pregnane X receptor ligand rifampin (INN, rifampicin) (600 mg, 9 days), which up-regulates both P-glycoprotein and MRP2 but not CYP2D6. Rifampin decreased the AUC of carvedilol to an extent independent of the CYP2D6 genotype (poor metabolizers, 341 +/- 147 ng. h/mL versus 126 +/- 41.7 ng. h/mL; extensive metabolizers, 173 +/- 102 ng. h/mL versus 74 +/- 41.4 ng. h/mL; both P <.05). The AUC was significantly correlated with intestinal expression of MDR1 mRNA (r = -0.671, P =.001) and MRP2 mRNA (r = -0.595, P <.006).

CONCLUSIONS

Variable plasma concentrations of carvedilol during long-term administration are predicted by CYP2D6 genotype and intestinal expression of P-glycoprotein and MRP2.

Comparison of waterjet dissection and ultrasonic aspiration: an in vivo study in the rabbit brain

Object. The waterjet method of dissection has been shown to enable the precise dissection of the parenchyma vessels while preserving blood in cadaveric pig brains. The waterjet device has also been applied clinically to treat various diseases and disorders without complications. Evidence still remains to be gathered as to how the instrument performs in reducing surgical trauma, intraoperative blood loss, and postsurgical brain edema. In the present study the authors investigate these parameters in a comparison between waterjet dissection and ultrasonic aspiration in the rabbit brain in vivo.

Methods. Thirty-one rabbits received identical bilateral frontal corticotomies, which were created using the waterjet device or an ultrasonic aspirator. The animals were killed 1, 3, or 7 days, or 6 weeks after surgery and their brains were processed for immunohistological analysis. Blood vessel preservation, intraoperative hemorrhage, postsurgical brain edema, and posttraumatic microglial and astoglial reactions were evaluated. Only in animals subjected to waterjet dissection were preserved vessels observed within the corticotomies. In addition, less intraoperative bleeding occurred in animals in which the waterjet was used. The microglial reaction was significantly reduced by waterjet dissection compared with ultrasonic aspiration; however, no difference in edema formation or astrocytic reactivity was observed.

Conclusions. These results demonstrate that waterjet dissection appears to be less traumatic than ultrasonic aspiration with respect to intraoperative hemorrhage and postoperative microglial reactivity in the rabbit model. Nevertheless, no difference in edema formation could be demonstrated. It remains to be proven that the observed differences are of clinical relevance.

Expression and localization of the multidrug resistance protein 5 (MRP5/ABCC5), a cellular export pump for cyclic nucleotides, in human heart

The multidrug resistance protein 5 (MRP5/ABCC5) has been recently identified as cellular export pump for cyclic nucleotides with 3',5'-cyclic GMP (cGMP) as a high-affinity substrate. In view of the important role of cGMP for cardiovascular function, expression of this transport protein in human heart is of relevance. We analyzed the expression and localization of MRP5 in human heart [21 auricular (AS) and 15 left ventricular samples (LV) including 5 samples of dilated and ischemic cardiomyopathy]. Quantitative real-time polymerase chain reaction normalized to beta-actin revealed expression of the MRP5 gene in all samples (LV, 38.5 +/- 12.9; AS, 12.7 +/- 5.6; P < 0.001). An MRP5-specific polyclonal antibody detected a glycoprotein of approximately 190 kd in crude cell membrane fractions from these samples. Immunohistochemistry with the affinity-purified antibody revealed localization of MRP5 in cardiomyocytes as well as in cardiovascular endothelial and smooth muscle cells. Furthermore, we could detect MRP5 and ATP-dependent transport of [(3)H]cGMP in sarcolemma vesicles of human heart. Quantitative analysis of the immunoblots indicated an interindividual variability with a higher expression of MRP5 in the ischemic (104 +/- 38% of recombinant MRP5 standard) compared to normal ventricular samples (53 +/- 36%, P < 0.05). In addition, we screened genomic DNA from our samples for 20 single-nucleotide polymorphisms in the MRP5 gene. These results indicate that MRP5 is localized in cardiac and cardiovascular myocytes as well as endothelial cells with increased expression in ischemic cardiomyopathy. Therefore, MRP5-mediated cellular export may represent a novel, disease-dependent pathway for cGMP removal from cardiac cells.

Waterjet dissection in the brain: review of the experimental and clinical data with special reference to meningioma surgery

Waterjet dissection enables precise parenchymal dissection under preservation of vessels and reduction of intraoperative blood loss in general surgery. The present study reports our experimental and clinical results with this device in neurosurgery. Our experimental studies in the porcine cadaver brain show that the device allows very accurate, precise, and reliable dissection of the brain. A linear relationship between waterjet pressure and dissection depth was demonstrated. Vessel preservation was observed at pressures below 20 bar. Clinically, precise dissection of brain parenchyma and various tumors was performed without complications. Even in meningiomas, with their very variable firmness, vascularization, and adherence to the surrounding brain, accurate dissection could be achieved. However, while tumor separation from the brain was attained with high accuracy and vessel preservation in all cases, only in softer lesions resection by aspiration under vessel preservation was possible with pressures below 20 bar. In all, the waterjet device enables precise tissue dissection and vessel preservation in various pathologies including meningiomas. It could represent an addition to the neurosurgical armamentarium. Further studies will have to show dissection qualities of this device that are superior to conventional methods.

Water jet dissection in neurosurgery: experimental results in the porcine cadaveric brain

OBJECTIVE

Water jet dissection is currently under investigation as a new tool for use in neurosurgical procedures. The safety of this instrument has already been demonstrated. However, precise data demonstrating highly accurate tissue dissection in the brain in combination with vessel preservation are still missing.

METHODS

In this study, 50 porcine cadaveric brains were dissected with the use of several nozzle types (80-150 in microm diameter, coherent straight or helically turned jet) and several levels of water jet pressure (1-40 bars). The dissection characteristics in various brain regions and the basilar artery were evaluated morphologically.

RESULTS

The best results regarding reliable function, dissection accuracy, and the correlation of water jet pressure with dissection depth were obtained with the 120-microm Helix Hydro-Jet nozzle. An almost linear relationship of pressure increase with dissection depth was demonstrated. The dissection depth varied significantly up to threefold, depending on the area investigated (greatest resistance was in the brainstem, followed by hemispheres and then the cerebellum). Vessels including the basilar artery resisted pressure up to 15 bars in most cases, whereas the basilar artery was dissected significantly more often with higher pressure.

CONCLUSION

The results indicate that 1) use of the water jet enables very precise and reliable brain parenchyma dissection with vessel preservation under conditions corresponding to the clinical situation, and 2) the nozzle type and water jet pressure must be selected carefully according to the brain area and tissue targeted. This study provides the morphological basis for further research with the use of the water jet technique in the brain. The water jet's characteristics may make this device a useful addition to the neurosurgical armamentarium.

Role of variant Creutzfeldt-Jakob disease for safety of treatment with blood components: screening of lymphatic tissue is a potential tool for risk assessment

BACKGROUND

Transmissible spongiform encephalopathies (TSEs) are neuropathological diseases caused by prions. Prions are infectious particles (PrPSc) which can induce bovine spongiform encephalopathy and most likely also the related infectious disease, variant of Creutzfeldt-Jakob disease (vCJD). The exposure of humans to orally ingested BSE agent in contaminated meat products presumably led to the emergence of vCJD. In vCJD, prions can be detected immunohistochemically not only in neuronal tissue but also in lymphoreticular tissue. vCJD is of significance in transfusion medicine because of the hypothetical transmission of prions by blood products.

METHODS

An immunohistochemistry method was used to allow screening for vCJD in human lymphoreticular tissue.

RESULTS

PrPSc can be detected in the cerebrum and cerebellum of patients with sporadic Creutzfeldt-Jakob disease (sCJD) and in the lymph nodes, tonsils, and spleen of vCJD patients. This method has the major advantage of working in fixed specimens which are routinely saved in departments of pathology and therefore allows screening of large numbers of archived human lymphoreticular tissues in different regional areas and from different time points. Scrapie-positive lymphoreticular sheep tissue reacts similarly to human tissue of vCJD affected patients and is available in sufficient amounts to be used as positive control in screening programs.

CONCLUSION

A method is provided which is a feasible tool for an epidemiological screening program to assess the prevalence of the assumed infectious agent of vCJD, PrPSc, in various populations.

Early onset of cardiomyopathy in two brothers with X-linked Emery-Dreifuss muscular dystrophy

Two brothers are reported suffering from X-linked Emery-Dreifuss muscular dystrophy caused by a 59bp deletion eliminating nucleotides 329-388 of the STA gene. Besides the typical findings for Emery-Dreifuss muscular dystrophy, both patients showed an unusual early onset of cardiac symptoms at age 6 and 9 years, respectively, coinciding with unusual high creatine kinase. A cardiological follow up showed worsening of the cardiac condition in the beginning of the second decade. The two boys described here belong to the very few Emery-Dreifuss muscular dystrophy patients with early onset of cardiac involvement and contribute to the variability of cardiac symptoms in Emery-Dreifuss muscular dystrophy.

The effects of the human MDR1 genotype on the expression of duodenal P-glycoprotein and disposition of the probe drug talinolol

BACKGROUND AND OBJECTIVES

A single-nucleotide polymorphism (SNP) of the human multidrug-resistance gene in wobble position of exon 26 reportedly predicts expression and function of P-glycoprotein in human enterocytes and lymphocytes. Several other allelic variants of MDR1 have been identified, some of which lead to amino acid exchange with as yet unknown functional relevance.

METHODS

In healthy white volunteers, we investigated the influence of the hereditary variants C3435T in exon 26 and G2677T/A (Ala893Ser/Thr) in exon 21 and the influence of 7 frequent or putative functional SNPs on duodenal MDR1 messenger ribonucleic acid (n = 32) and immunoreactive P-glycoprotein (n = 37) expression. Moreover, the disposition of the probe drug talinolol was evaluated in 55 subjects after oral administration (100 mg) and in 23 subjects after intravenous administration(30 mg).

RESULTS

Duodenal MDR1 messenger ribonucleic acid and P-glycoprotein, as assessed by real-time polymerase chain reaction (TaqMan) and immunostaining, were not influenced by any MDR1 polymorphism studied. Talinolol disposition was not affected by the exon 26 mutation C3435T. In carriers of the TT/TA variants of G2677T/A, the area under the serum concentration-time curve values of oral talinolol were slightly but significantly elevated compared with those in carriers of at least 1 wild-type allele (P <.05, Kruskal-Wallis test; P =.014, Mann-Whitney U test). However, multiple comparisons with combinations of putative functional SNPs did not confirm a significant influence of the MDR1 genotype on talinolol disposition.

CONCLUSIONS

We did not identify any influence of MDR1 genotypes on duodenal expression of P-glycoprotein and disposition of talinolol in humans.

Expression and localization of P-glycoprotein in human heart: effects of cardiomyopathy

ABC-type transport proteins, such as P-glycoprotein (P-gp), modify intracellular concentrations of many substrate compounds. They serve as functional barriers against entry of xenobiotics (e.g., in the gut or the blood-brain barrier) or contribute to drug excretion. Expression of transport proteins in the heart could be an important factor modifying cardiac concentrations of drugs known to be transported by P-gp (e.g., beta-blockers, cardiac glycosides, doxorubicin). We therefore investigated the expression and localization of P-gp in human heart. Samples from 15 human hearts (left ventricle; five non-failing, five dilated cardiomyopathy, and five ischemic cardiomyopathy) were analyzed for expression of P-gp using real-time RT-PCR, immunohistochemistry, and in situ hybridization. Immunohistochemistry revealed expression of P-gp in endothelium of both arterioles and capillaries of all heart samples. Although P-gp mRNA was detected in all samples, its expression level was significantly reduced in patients with dilated cardiomyopathy. We describe variable expression of P-gp in human heart and its localization in the endothelial wall. Thus, intracardiac concentrations of various compounds may be modified, depending on the individual P-gp level.

Effect of levothyroxine administration on intestinal P-glycoprotein expression: consequences for drug disposition

OBJECTIVE

Thyroid function alters the pharmacokinetics of many drugs; one example is the cardiac glycoside digoxin. Because digoxin disposition is affected by intestinal expression of P-glycoprotein, we hypothesized that thyroid hormones may regulate P-glycoprotein and influence disposition of P-glycoprotein substrates.

METHODS

Duodenal expression of P-glycoprotein measured by reverse transcriptase-polymerase chain reaction of MDR1 messenger ribonucleic acid (mRNA) and by immunohistochemical examination was studied in 8 healthy volunteers (4 men and 4 women; age range, 22-29 years; body weight, 59-89 kg) before and after coadministration with levothyroxine (200 microg orally for 17 days), which resulted in suppression of thyroid-stimulating hormone. The pharmacokinetics of the P-glycoprotein substrate talinolol was assessed after intravenous (30 mg) and oral (100 mg) administration.

RESULTS

Duodenal MDR1 mRNA expression and immunoreactive P-glycoprotein were increased 1.4-fold (not significant; P =.078) and 3.8-fold (P <.01), respectively, after administration of levothyroxine. The changes in P-glycoprotein expression were associated with minor alterations in talinolol half-life after both oral and intravenous administration.

CONCLUSIONS

Expression of intestinal P-glycoprotein in humans appears to be influenced by thyroid hormones. The functional consequences need to be addressed in patients with hyperthyroidism.

Ectopic cervical thymus in a 12-year-old boy: a case report

The case of a 12-year-old boy with ectopic cervical thymus is reported. This is a rare differential diagnosis in cervical tumors in childhood. The clinical symptoms might present as complications; in rare cases malignant transformations have been reported. The diagnosis ectopic cervical thymus can be achieved only histologically. Due to possible malignant transformation, it is mandatory to excise this thymus tumor totally.

Induction of P-glycoprotein by rifampin increases intestinal secretion of talinolol in human beings: a new type of drug/drug interaction

BACKGROUND

P-Glycoprotein is an efflux pump in many epithelial cells with excretory function. It has been demonstrated that rifampin (INN, rifampicin) induces P-glycoprotein, particularly in the gut wall. We therefore hypothesized that rifampin affects pharmacokinetics of the P-glycoprotein substrate talinolol, a beta1-blocker without appreciable metabolic disposition but intense intestinal secretion in human beings.

METHODS

Pharmacokinetics of talinolol (a single dose of 30 mg administered intravenously or 100 mg administered orally for 7 days) and duodenal expression of the MDR1 gene product P-glycoprotein as assessed by reverse transcriptase-polymerase chain reaction of the MDR1-messenger ribonucleic acid, by immunohistochemistry and Western blot analysis were analyzed before and after coadministration of rifampin (600 mg per day for 9 days) in 8 male healthy volunteers (age 22 to 26 years).

RESULTS

During rifampin treatment, the areas under the curve of intravenous and oral talinolol were significantly lower (21% and 35%; P < .05). Treatment with rifampin resulted in a significantly increased expression of duodenal P-glycoprotein content 4.2-fold (2.9, 6.51) (Western blot) and messenger RNA was increased in six of the eight volunteers. P-Glycoprotein expression in biopsy specimens of gut mucosa correlated significantly with the systemic clearance of intravenous talinolol (rs = 0.74; P < .001).

CONCLUSIONS

Rifampin induces P-glycoprotein-mediated excretion of talinolol predominantly in the gut wall. Moreover, clearance of talinolol from the blood into the lumen of the gastrointestinal tract may be predicted by the individual intestinal P-glycoprotein expression. Thus we describe a new type of steady-state drug interaction affecting compounds that are subject to transport rather than metabolism.

Treatment with nimodipine or mannitol reduces programmed cell death and infarct size following focal cerebral ischemia

The present study was conducted to evaluate the effects of nimodipine and mannitol on infarct size and on the amount of apoptosis after transient focal cerebral ischemia. Focal cerebral ischemia was induced in male Sprague-Dawley rats (weight 300-380 g) by transient occlusion of the right middle cerebral artery (MCAO) using an intraluminal thread model. All animals underwent ischemia for 2 h, followed by 24 h of reperfusion. Group I (n=16) was untreated. Group II (n=16) received 15% mannitol (1 g/kg as bolus) and group III (n=9) received 15 microg/kg/h nimodipine intravenously beginning 15 min prior to MCAO. Twenty-four hours after reperfusion, the brain was taken and sectioned in coronal slices. The slices were stained with H&E and with the transferase dUTP nick-end labeling (TUNEL) technique. Histopathological analysis revealed a significant (P<0.05) decrease in infarct size in the striatum with both drugs: mannitol (group II) 25.4+/-5.9% and nimodipine (group III) 21.5+/-11.0% versus control (group I) 34.9+/-7.0% and in the cortex 2.7+/-2.0% (group II) and 6.3+/-2.4% (group III) versus control 14.4+/-9.0% (group I). The number of apoptotic cells was statistically lower in the therapy groups (group III 9.6, group II 25.8) versus control (group I 57.9) (Mann-Whitney-Wilcoxon U-test Z>1.96, P<0.05). This study indicates that mannitol and nimodipine provide neuroprotection by preventing both the necrotic and apoptotic components of cell death after transient focal cerebral ischemia and may be effective as neuroprotective drugs for cerebrovascular surgery.

Severe clinical expression in X-linked Emery-Dreifuss muscular dystrophy

X-linked Emery-Dreifuss muscular dystrophy (EDMD) is a relatively rare benign neuromuscular disorder which can vary remarkably in onset, course and severity. In the present study, a TCTAC deletion spanning the nucleotides 631-635 of the emerin gene caused an unusually severe disease phenotype including loss of ambulation and severe muscle wasting in two affected brothers. The same mutation has been reported previously in an unrelated family showing a significantly milder phenotype. The interfamilial heterogeneity in distribution and in severity of the features in the two families point to environmental or genetic modification as the cause of clinical variability in Emery-Dreifuss muscular dystrophy.

Waterjet dissection of the brain: experimental and first clinical results. Technical note

Control of bleeding during dissection is a problem that is still not completely resolved in neurosurgical procedures. To overcome this problem in some settings, the authors, in close collaboration with their institution, developed a new device for blunt dissection of brain tumors that is based on a waterjet technique. This report describes their first experimental and clinical experience with this new method. Numerous cutting experiments were performed in porcine cadaver brains. The best results were obtained using pressures from 4 to 6 bars with a 100-microm tip, which produced very small, precise cuts. Histological evaluation showed no disruption or vacuolization of the surrounding tissue. The authors have used the new device in nine patients (seven with gliomas and two undergoing temporal lobe resections for epilepsy), and no complications have been observed. The waterjet device allowed dissection of the brain tissue while even small exposed vessels were spared injury. The instrument was found to be easy to use. Future investigations will concentrate on adapting this new method to endoscopic surgery and evaluating fluids with low surface tension to avoid foaming and bubbling during open surgery.

[Primary high malignancy B-cell lymphoma of the lacrimal sac]

Case report on a 44-year-old woman in good health with the symptoms of epiphora, a plump elastic, not distressing swelling under the medial canthal tendon of 1 cm size on the right side. In ultrasonography and intraoperatively a tumour of moderate reflectivity with infiltration of the lacrimal sac was found. The histological evaluation, including immunohistochemical studies of the removed lesion, revealed a malignant B-cell lymphoma.

Classification, oscillatory and alternating oscillatory firing of alpha 1 (FF) and alpha 2-motoneurons (FR) in patients with spinal cord lesion

Single-nerve fibre action potentials (APs) were recorded extracellularly from sacral nerve roots of people with spinal cord lesion (patients with paraplegia). Single-fibre APs of certain fibres were identified by the conduction velocity and the AP waveform, and simultaneous impulse patterns were extracted from the summed impulse traffic and analysed with respect to spacio-temporal relationships. The velocity values of components of compound APs, induced by electrical nerve root stimulation or electrical intravesical stimulation, were similar to the group conduction velocity values obtained from single-nerve fibre APs of natural impulse traffic. When changing the root temperature in one case from 32 degrees C to 35.5 degrees C, the group conduction velocities changed in the following way: secondary muscle spindle afferents (SP2): 40 m/s (32 degrees C) to 50 m/s (35.5 degrees C); bladder stretch afferents (S1): 31.3 to 40 m/s; bladder tension afferents (ST): 25 to 33.8 m/s; mucosal afferents (M): 12.5 to 13.8 m/s; alpha 1:-; alpha 2-motoneurons: 40 to 50 m/s; alpha 3: 33 to 40 m/s. The group conduction velocities showed different temperature dependence apart from SP2 fibres and alpha 2-motoneurons, which were therefore used for calibration. The distance between two Pacinian corpuscle (PC) receptors in a sacral dermatome of one paraplegic patient was calculated to be approximately 20 mm. A similar distance between PC receptors was found in a brain-dead individual. Receptor densities seem therefore to remain unchanged following spinal cord lesion. Motoneurons fired irregularly repeatedly with impulse trains. In paraplegics the oscillation periods and the interspike intervals of the impulse trains varied much more than observed for brain-dead and normal individuals. Motoneurons could therefore not always be identified by their pattern of oscillatory firing. Alternating long and short oscillation periods (T) could be measured in an oscillatory firing alpha 1 (T = 125 ms) and alpha 2-motoneuron (T = 150 ms). In both cases the average difference between the alternating oscillation periods was 5 ms. Tremor, alternating long and short oscillation periods, cellular oscillator properties, and recurrent excitation and inhibition are discussed with respect to the oscillator theory of the functioning of the human central nervous system. Mathematical predictions from populations of interacting biological oscillators are compared to measurements on neuronal network data.

Classification of human peripheral nerve fibre groups by conduction velocity and nerve fibre diameter is preserved following spinal cord lesion

(1) Single nerve fibre action potentials (APs) of lower sacral nerve roots were recorded extracellularly with two pairs of wire electrodes during an operation in which an anterior root stimulator for bladder control was implanted in 9 humans with a spinal cord lesion and dyssynergia of the urinary bladder. Roots that were not saved and that were used to record from were later used for morphometry. (2) Nerve fibre groups were identified by conduction velocity distribution histograms of single afferent and efferent fibres and partly by nerve fibre diameter distribution histograms, and correlation analysis was performed. Group conduction velocity values were obtained additionally from compound action potentials (CAPs) evoked by electrical stimulation of nerve roots and the urinary bladder. (3) The group conduction velocities and group nerve fibre diameters had the following pair-values at 35.5 degrees C: Spindle afferents: SP1 (65 m/s/13.1 microns), SP2 (51/12.1); touch afferents: T1 (47/11.1), T2 (39/10.1), T3 (27/9.1), T4 (19/8.1); urinary bladder afferents: S1 (41 m/s/-), ST (35/-); alpha-motoneurons: alpha 13 (-/14.4), alpha 12 (65m/s/13.1 microns), alpha 11 (60?/12.1)(FF), alpha 2 (51/10.3)(FR), alpha 3 (41/8.2)(S); gamma-motoneurons: gamma beta (27/7.1), gamma 1 (21/6.6), gamma 21 (16/5.8), gamma 22 (14/5.1); preganglionic parasympathetic motoneurons: (10 m/s/3.7 microns). (4) The values of group conduction velocity and group nerve fibre diameter measured in the paraplegics were very similar to those obtained earlier from brain-dead humans and patients with no spinal cord lesions. Also, the number and the density of myelinated fibres were preserved in the roots. Thus, the classification and identification of nerve fibre groups remained preserved following spinal cord lesion. A direct comparison can thus be made of natural impulse patterns of afferent and efferent nerve fibres between paraplegics (pathologic) and brain-dead humans (supraspinal destroyed CNS, in many respects physiologic). (5) When changing the root temperature from 32 degrees C to 35.5 degrees C, the group conduction velocities changed in the following way in one case: SP2: 40 m/s (32 degrees C) to 50 m/s (35.5 degrees C), S1: 31.3 to 40, ST: 25 to 33.8, M: 12.5 to 13.8; alpha 2: 40 to 50, alpha 3: 33 to 40. The group conduction velocities showed different temperature dependence apart from SP2 fibres and alpha 2-motoneurons. (6) Upon retrograde bladder filling the urinary bladder stretch (S1) and tension receptor afferent (ST) activity levels were undulating and increased.(ABSTRACT TRUNCATED AT 400 WORDS)

Immuno-lectin histochemistry and ultrastructure in two cases of globoid cell leukodystrophy (Krabbe's disease)

Two cases of globoid cell leukodystrophy (Krabbe's disease) have been studied by means of conventional histological, immunohistochemical and ultrastructural methods. Lectins specific for several different carbohydrates, Ricinus communis (RCA-1), peanut agglutinin (PNA), wheat germ agglutinin (WGA) and Concanavalin A (Con A) have been utilized both at optical and ultrastructural level. In both cases a strong positive labeling of the globoid cells could be observed light-microscopically. Ultrastructurally immunogold deposits only of RCA-I and WGA in the typical Krabbe's inclusions have been clearly demonstrated.

Enhancement of nerve fibre regeneration by nucleotides after peripheral nerve crush damage. Electrophysiologic and morphometric investigations

The effect of nucleotide administration on the regeneration of myelinated nerve fibres following crush injury to the sciatic nerve of the rat was studied using both morphometric and electroneurophysiologic techniques. After a standardized localized crush lesion of the right sciatic nerve, rats were given nucleotides daily at a dosage of 3.0 mg/kg body wt uridine monophosphate (UMP), 2.5 mg/kg body wt cytidine monophosphate (CMP) or 3.0 plus 2.5 mg/kg body wt UMP plus CMP, respectively. Observations were made after 20, 40 and 60 days of nerve regeneration for comparison with age-matched crushed or nonoperated controls. Electroneurophysiologic studies of right sural nerves were performed as single fibre measurements. Morphometry was performed on semithin transverse sections of the right common peroneal nerve with a fully automatic interactive image analysis system. Forty days after crush injury the single fibre conduction velocity of all type II afferents in the UMP/CMP treated group was significantly accelerated. There was a trend (10% greater than or equal to p greater than or equal to 5%) to increase of mean efferent single nerve fibre function at this time. Morphometry of nerve fibres revealed a trend to enlargement of mean fibre area and mean fibre diameter related to increased myelin area and myelin thickness. After 60 days, there was a trend to increase of single fibre conduction velocity of all type II afferents in the UMP/CMP treated group. Automated morphometry revealed a significant increase for the following parameters: fibre area, fibre diameter, myelin area, myelin thickness and axon area.(ABSTRACT TRUNCATED AT 250 WORDS)

[Mucopolysaccharidoses. Genetics, clinical pathology, therapeutic regimes]

In recent years, several clinical and biochemical studies have been published contributing to better understanding of mucopolysaccharide storage diseases. Our purpose, therefore, is, to give an updated survey of this group of lysosomal diseases for diagnostic orientation to the pathologist. The present classification of mucopolysaccharidoses is based on a mixture of clinical symptoms, demonstration of enzyme defects, analysis of urinary excretion of glycosaminoglycans (mucopolysaccharides) and historical eponyms. A broad heterogeneity has been revealed: identical enzyme defects may lead to severe mental and physical deterioration and death during childhood or to mild forms with normal adult height, intelligence, and life expectancy. Conversely, identical phenotypes may result from mutations of different genes. Various types of mucopolysaccharidoses are mostly characterized by quantitative differences of main symptoms (coarse facial features, various skeletal abnormalities, hepatosplenomegaly, corneal clouding, mental retardation, and cardiac failure). Morphologically, storage material can be observed practically in all tissues by light and/or electron microscopy. Until recently, no more than palliative treatment could be offered. In the last decade, bone marrow transplantation has become available and may have beneficial effects in selected cases. The genes of several lysosomal enzymes have been identified, and comprehensive studies to introduce the gene into defective cells are currently undertaken. However, substantial efforts are still necessary until gene transfer will become available for patients with mucopolysaccharidoses.

Argyrophil and beta-endorphin immunoreactive cells in focal islet-cell adenomatosis and insulin-producing islet-cell adenomata

Pancreatic tissue from 3 cases of hyperinsulinemic hypoglycemia was examined using histochemical and immunoperoxidase staining techniques. The insular lesions present were adenomatosis and insulin-producing islet-cell adenomata. The great majority of the islet parenchymal cells in these lesions were reactive with antibodies to pro-insulin, C-peptide, and insulin. A variable number of islet cells was found to react with beta-endorphin antiserum in all 3 cases, while the reaction with antiserum against the neural tissue marker antigen, S-100, was restricted to the cases with islet-cell adenoma. Argyrophil parenchymal cells were present in focal adenomatosis but almost absent in insulomata. These results suggest that various lesions of the endocrine pancreas causing hypoglycemia can be distinguished by means of specific histo- and immunocytochemical methods because of differences in the distribution of characteristic cellular antigens.

Causes of death in insulin-dependent diabetic patients treated with hemodialysis

Causes of death were analyzed for 63 diabetic patients treated with hemodialysis. In all cases, autopsy-based death certificates were evaluated. The causes of death were compared during the periods 1969 through 1979 versus 1980 through 1987, and the causes of death in patients who died after less than 18 months versus those who died greater than 18 months after starting hemodialysis treatment. Our population of decreased diabetics had a mean age of 41.8 years, with a mean of 23.4 years of diabetes duration. The mean age at manifestation of diabetes was 18.2 years. Cardiac failure has been shown to be the most prevalent cause of death (55.6%), while sepsis accounted for 20.6% of the deaths. In both the period from 1969 through 1979 and that from 1980 through 1987, cardiac failure was identified as the commonest cause of death, with an equal proportion of septic causes (i.e., 20% versus 21.05%). When comparing causes of death among diabetics on hemodialysis for less than 18 months versus those receiving greater than 18 months of treatment, cardiac failure was responsible for 54% versus 61.5% of deaths. Septic causes were found to be more prevalent after a longer duration of treatment (i.e., 30.8%). Therefore, it is concluded that to prevent cardiac deaths, blood pressure control has to be as tight as possible in patients with diabetic kidney disease. To prevent late-occurring septic deaths, good nutritional status in patients undergoing hemodialysis seems to be of importance. The prevention of macroangiopathy in diabetes represents a major medical problem that needs to be solved.

[Ileus of the small intestine caused by intestinal anisakiasis (herring worm disease)]

Two cases of anisaciasis caused by eating of improperly prepared herrings which were infested with larval nematodes are reported. The acute type with a stenosing process in the small intestinal wall existed in both cases which resulted in an ileus. Therapy was resection of the affected intestinal part with end-to-end-anastomosis. The morphological proof of larval nematodes, which penetrate from lumen into the eosinophilic granulomata, pseudotumours and eosinophilic microabscesses are important histological findings. It should be considered the possibility of a herring worm disease in the case of an acute abdomen caused by an inflammatory small bowel stenosis.

[Ultrastructural findings in testicular feminization]

On the basis of light and electron microscopic findings problems of the morphology of gonads in testicular feminization syndrome (TF) are discussed. Within the tubules 3 cell types (light, dark, intermediate) can be distinguished which are regarded as different functional forms of Sertoli cells. Germ cells were not observed definitely. There are, however, remarkable difficulties in morphological distinction between undifferentiated Sertoli and germ cells. It is underlined that fine structure of gonads and cellular composition of tubules as well as the amount of interstitial cells depend on the age of the individuum and on the form of TF (complete and incomplete).

[The neuroblastoma of the cerebellum]

A report is given demonstrating the maturation of a neuroblastoma of the cerebellum and its transformation into a ganglioglioma. In a male infant statomotor retardation was diagnosed at the age of 6 months. 9 months later, he developed symptoms indicating a cerebellar neoplasm. Craniotomy showed a vermian tumor which was classified histologically as a neuroblastoma. 51/2 years after the first operation, a control CT scan revealed a recurrence which showed light and electron microscopically the structure of a ganglioglioma. The child is now 8 years old and develops relatively well. On the basis of this observation and of the limited data published in the literature, it is suggested that, with the aid of light microscopy, it is possible to distinguish neuroblastomas from common medulloblastomas what is of practical importance because neuroblastomas seem to have a better prognosis. However, differential diagnostic criteria need further precision. Problems of the nosological placement of neuroblastomas and their histogenetic relationship to medulloblastomas are discussed. The statement of the WHO Classification of Tumors of the CNS that neuroblastomas correspond to grade IV cannot be accepted generally.