"Mesenchymal tumor" or "decidual-like reaction"?

For more than 40 yr, an unusual urinary bladder lesion has been known to occur in certain strains of mice, but no consensus has been obtained regarding its etiology, pathogenesis, biology, or classification. The lesion was first assumed to be epithelial and non-neoplastic, then it was called a smooth muscle cell tumor or leiomyosarcoma because of ultrastructural characteristics for smooth muscle cells. Later, the nonspecific term "mesenchymal tumor" was introduced due to histomorphologic differences from all smooth muscle tumors known. Recently, a proposal was made to name it "decidual-like reaction" because of the histomorphologic similarity to the rare spontaneous decidual reaction in the uterus of aging mice. Both lesions are characterized by spindle and large pleomorphic epithelioid cells with large bizarre nuclei; these characteristics mimic anaplasia of malignant tumors and led pathologists to assume a neoplastic nature. The decidual hypothesis is supported by the regular presence of nuclear progesterone receptors, the occasional occurrence of eosinophilic cytoplasmic granules, the rare finding of cells morphologically resembling granulated metrial gland cells (all also observed in the uterine decidual reaction), and the reproducibility through long-term feeding of combinations of estrogens and progestogens. It appears that the new decidual hypothesis can explain many detailed facets of the lesion, with the exception of the reported smooth muscle cell characteristics. The controversy of "mesenchymal tumor versus decidual-like reaction" should be resolved soon, not only as a scientific issue, but also because of consequences for risk assessment.     

Einzelreferate und Buchbesprechungen

Ohne Zusammenfassung     

Quantification of functional deficit in Alzheimer's disease using a computer-assisted mapping program for99mTc-HMPAO SPECT

A computer-assisted mapping program was developed to determine changes of cerebral perfusion in normal and pathological aging using single photon emission computer tomography (SPECT) and^99mTc-hexamethylpropyleneamine oxime (HMPAO). The software program outlined the cortex on 14 adjacent brain slices, and superimposed a ring of 12 regions of interest on each slice. Regional/global and regional/cerebellar relative flow values were calculated in 27 patients with clinically diagnosed Alzheimer's disease (AD) (mean age 71 years, SD 7.6) and in 10 normal controls (mean age 73.7 years, SD 7.3). The Dementia Rating Scale (DRS) was used to assess mental status in all subjects. Multiple regression analysis demonstrated a significant correlation between relative flow values and the DRS score. Regional/cerebellar (R=0.88,p<0.0001) relative flow values were a better indicator of cortical impairment than regional/global relative flow values (R=0.68,p=0.003). Of the brain regions of interest, the left parietal flow values correlated best with the DRS score (r=0.83,p<0.0001), a cutoff value of 77 accurately classifing 80% of the normals and 100% of the patients diagnosed as having Alzheimer's disease. The data show that computer-assisted mapping of SPECT can provide semiquantitative flow values with high diagnostic accuracy.     

Milzverletzung im Rahmen einer Koloskopie mit t?dlichem Verlauf

A case of splenic injury following a diagnostic colonoscopy with fatal outcome is reported. Splenic injury is a rare complication of colonoscopy. The most likely mechanism is tension and shearing force on the splenicolic ligament and adhesions in the left upper abdomen. In this case medical malpractice because of perforation of the colon was assumed but could not be confirmed by the autopsy findings.     

Subcortical damage and cortical dysfunction in progressive supranuclear palsy demonstrated by positron emission tomography

Summary Regional cerebral glucose metabolism was studied in nine patients with progressive supranuclear palsy (PSP). (¹⁸F)-2-fluoro-2-deoxy-d-glucose (FDG) positron emission tomography (PET) revealed general cerebral hypometabolism in all PSP patients in comparison with an age-matched reference group. When comparing the degree of regional metabolic deterioration, a consistent pattern of the most affected brain regions became obvious: the strongest significant alteration of cerebral glucose metabolism was observed in subcortical regions, e.g. in caudate nucleus, lentiform nucleus and upper mid-brain, which showed nerve cell loss in previous pathological studies. Less severe, but still significant hypometabolism was observed in frontal cortex. This pattern of hypometabolism was distinctly different from that typically seen in dementias of Alzheimer's type. The present data show that PET findings agree with histopathological studies: PSP is a primarily subcortical disease with secondary inactivation of cortical, especially of frontal brain regions.     

Knochenwachstum in porösen,keramischen Implantaten beim Hund

Zusammenfassung Definiert poröse zylindrische (Radius 2,5 mm) und halbzylindrische (Radius 6,5 mm) Implantate aus resistenter Aluminiumoxidkeramik mit den Porendurchmessern 0,4 bis 0,6 mm, 0,6 bis 0,8 mm, 0,8 bis 1,0 mm und 1,0 bis 1,2 mm wurden in die Tibia von Hunden implantiert. In den Poren bildete sich in zunehmendem Maße Knochengewebe, und nach einer Verweilzeit von 7 Monaten enthielten fast alle Poren vorwiegend Knochen-gewebe. In zylindrischen Implantaten aus Calciumphosphat (Radius 2,5 mm) mit 0,8 bis 1,0 mm Porendurchmesser erfolgte die Knochenbildung innerhalb der zweimonatigen Verweilzeit deutlich schneller als in vergleichbaren Implantaten aus A1203 und in Implantaten aus Calciumphosphat-Calciumaluminat mit 0,8 bis 1,0 mm Porendurchmesser.Zwischen Knochen und Calciumphosphat-Implantat entstand eine direkte Verbindung ohne erkennbaren Bindegewebssaum. Zwischen Knochen und Al₂O₃-Keramik hingegen war ein schmaler, zwischen Knochen und Calciumphosphat-Calciumaluminat ein vergleichsweise breiter Bindegewebssaum vorhanden.Die Gewebeverträglichkeit war bei Calciumphosphat optimal. In der Umgebung von Al₂O₃ traten nach mehrwöchiger Verweilzeit geringgradige Fremdkörperreaktionen auf, in der Umgebung von Calciumphosphat-Calciumaluminat nach 2 Monaten starke Fremdkörperreaktionen.

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Bone growth in porous ceramic implants in dogs

Summary Cylindrical (radius 2.5 mm) and semicylindrical (radius 6.5 mm) implants of nondegradable alumina of defined porosity (pore diameters 0.4 to 0.6 mm, 0.6 to 0.8 mm, 0.8 to 1.0 mm and 1.0 to 1.2 mm) were implanted in the tibiae of dogs. The pores were filled to an increasing extent with bone tissue, so that after a period of seven months almost all the pores contained bone tissue. Cylindrical implants (radius 2.<5 mm) of calcium phosphate with 0.8 to 1.0 mm pore diameter were more rapidly filled with bone tissue within 2 months than implants of A1₂O₃ and of calcium phosphate-calcium alumina with 0.8 to 1.0 mm pore diameter.Direct contact was established between the calcium phosphate implants and new bone, i.e. without any seam of connective tissue. Between the bone and the Al₂O₃ ceramic on the other band, there was a narrow seam of connective tissue, and a relatively broad seam was observed between the bone and the calcium phosphate-calcium alumina implant.The calcium phosphate implants had an excellent tissue compatibility. In the vicinity of the Al₂O₃ implants minor, and in the case of the calcium phosphate-calcium alumina implants major foreign body reactions occurred after 2 months.

Die Untersuchungen sind Teil einer Forschungsarbeit, die das Battelle-Institut, Frankfurt a. M., im Auftrag des Bundesministeriums für Forschung und Technologie durchführt.     

Experiments on the Babesia bigemina carrier state in East African buffalo and eland

Three captive East African buffalo (Syncerus caffer) were injected with 5 x 109 bovine erythrocytes with Babesia bigemina pathogenic for cattle. None of the buffalo showed signs of disease, but Babesia were found in blood smears for four days indicating their multiplication. The carrier state of Babesia bigemina was established in two buffalo for 28 and 147 days respectively by sub-inoculation into splenectomized calves, while no parasites were demonstrated 28 days after injection in the third buffalo. Two buffalo shot in Kenya did not appear to be carriers of Babesia gibemina, as shown by sub-inoculation of blood in splenectomized calves. Two captive eland (Taurotragus oryx) were inoculated and their blood investigated as with the experimental buffalo. Neither eland appeared to harbour Babesia bigemina 28 days after injection, even though one was splenectomized. The experimental data indicate that the East African buffalo can be a carrier of Babesia bigemina for at least 5 months, while this parasite did not survive in eland. Buffalo may play a role in the epidemiology of babesiosis in cattle, while eland most likely do not.     

Electrode dysfunctions in patients with deep brain stimulation: a clinical retrospective study

Background  

Electrode fractures are known hardware problems in patients with deep brain stimulation (DBS) and require surgical revision. Short circuits, loose connections or disconnections of only single contacts of the common quadripolar stimulation electrodes are more subtle dysfunctions and can result in decreased efficacy of DBS. Measuring the impedances of electrodes helps detect such technical dysfunctions. This study evaluates the frequency and clinical implications of abnormal impedance measurements.