Rapidly growing calcified cerebellar astrocytoma in infants

We report the case of an infant with a cerebellar astrocytoma that showed marked calcification within only 6 months. In general, only slow-growing tumors tend to calcify. To our knowledge, no other case of such rapid calcification in cerebellar astrocytoma has been reported.     

A brainstem variant of reversible posterior leukoencephalopathy syndrome (RPLS) presenting with visual disturbance]

A 40-year-old woman noticed blurred vision of the right eye. The optic disc edema of bilateral eyegrounds was noted, and brain MRI showed abnormal signals of the brainstem at a neurosurgical clinic. On her first visit, blood pressure was as remarkably high as 250/130 mmHg. Neurologically, only optic disc edema of bilateral eye-grounds was found. Both T2-weighted MRI and FLAIR showed hyperintense signal areas mainly from the ventral pons to medulla oblongata. These areas were not enhanced with gadolinium. About three weeks after the administration of an antihypertensive agent, brain MRI revealed no abnormal signal. About three months later, the blurred vision disappeared and ophthalmological abnormalities subsided. We diagnosed her with a brainstem variant of RPLS, presenting with visual disturbance caused by hypertensive retinopathy.     

Development and Initial Testing of a Permanently Implantable Centrifugal Pump

Abstract: To be able to salvage heart failure patients, the need for an economical permanent ventricular assist device is increasing. To meet this increasing demand, a miniaturized centrifugal blood pump has been developed as a permanently implantable device. The Gyro permanently implantable model (PI-601) incorporates a sealless design with a blood stagnation free structure. The pump impeller is magnetically coupled to the driver magnet in a sealless manner. This pump is atraumatic and antithrombogenic and incorporates a double pivot bearing system. A miniaturized actuator was utilized in this system in collaboration with the University of Vienna. The priming volume of this pump is 20 ml. The overall size of the pump actuator package is 53 mm in height and 65 mm in diameter, 145 ml of displacement volume, and 305 g in weight. Testing to date has included in vitro hydraulic performance and hemolysis. This pump can provide 5 L/min against a 110 mm Hg total pressure head at 2,000 rpm and 8 Limin against 150 mm Hg at 2,500 rpm. The normalized index of hemo-lysis (NIH) value of this pump was 0.0028 g/100 L at 5 Limin against 100 mm Hg. A preliminary anatomical study revealed the possibility of the implantability of 2 such systems in biventricular bypass at a preperitoneal location. This system is feasible for use as a permanently implantable biventricular assist device.     

SARCOIDOSIS OF THE SPINAL CORD

The authors report a female elderly patient with quadriplegia, hypesthesia below the neck, and rectourinary dysfunction, which were found at autopsy to have been caused by involvement of the lower cervical and upper thoracic segments of the spinal cord in systemic sarcoidosis. Sixty cases of spinal cord sarcoidosis reported in the literature are also reviewed. Most patients had clinical signs which mimicked those of a spinal cord tumor or meningomyelitis. Only in less than one-third of the cases had sarcoidosis been diagnosed before neurological symptoms occurred. Macroscopically, most intramedullary lesions formed a mass, whereas extramedullary lesions usually manifested as meningitis. Histologically, perivascular distribution of sarcoid granulomas was noted in our patient as well as in many cases reported in the literature. The clinical course of the patients with spinal sarcoidosis was usually poor when early diagnosis was not made. ACTA PATHOL. JPN. 35: 1007–1022, 1985.     

Effect of 5-(p-hydroxyphenyl)-5-phenylhydantoin (p-HPPH) enantiomers,major metabolites of phenytoin,on the occurrence of chronic-gingival hyperplasia: in vivo and in vitro study

The purpose of this study was to assess the possible role of the (R)- and (S)- enantiomers of the phenytoin metabolite p-HPPH in the pathogenesis of gingival hyperplasia (GH). About 98% of circulating p-HPPH is in the (S)-form. There were significant differences between patients with and without GH in (R)-p-HPPH level (0.055 vs 0.042 g·ml^–1), both enantiomer/racemate level ratios, and R/S enantiomeric ratio (0.0313 vs 0.0232); an increase in serum (R)-p-HPPH level was observed in patients with GH. In separate experiments, the effect of p-HPPH enantiomers on the proliferation of the normal human dermal fibroblast was studied. The in vitro study showed that (R)-p-HPPH selectively stimulated fibroblast growth. The results suggest that the least abundant metabolite, (R)-p-HPPH, is the most toxic with respect to gingival hyperplasia.     

Comparison of the axonal and glial reactions between the caudal and rostral border in the cryoinjured dorsal funiculus of the rat spinal cord

Axonal and glial reactions to traumatic injury were compared between the caudal and rostral border of the lesion after freeze-injury to the C3 dorsal funiculus by attaching a liquid nitrogen-cooled copper probe to the dorsum of the rat spinal cord. The axonal and glial changes were examined up to 60 days postoperative by light and electron microscopy and immunohistochemistry for neurofilaments. Regenerative axonal changes and the appearance of numerous undifferentiated cells were found at the caudal border 7 days after cryoinjury. In contrast, such axonal and cellular reactions were scarce at the rostral border. Undifferentiated cells clearly manifested their phenotypes by differentiating into oligodendrocytes or astrocytes 11 days postinjury. The results indicated that glial cell reactions occurred in association with regenerative axonal changes at the proximal stump of the injured nerve fibers, suggesting that regenerating and demyelinated naked axons could be responsible for the appearance of the immature glial cells.     

Visual completion of partly occluded grating in infants under 1 month of age

Four groups of eight infants (3 weeks of age on average) were each habituated to one of four displays consisting of a grating of either low (0.4 cpd) or high (1.2 cpd) spatial frequency, whose central portion was covered up with a horizontal occluder which was either narrow (1.33 degrees) or broad (4.17 degrees). These habituation displays are referred to as LN (low spatial frequency grating and narrow occluder), LB (low and broad), HN (high and narrow), and HB (high and broad) displays. Posthabituation-test displays consisted of a complete grating (CG) of the same frequency as the habituated grating along with a separate grating (SG) whose central portion was replaced with a black gap of the same height as the occluder in the habituation displays. Infants habituated to the LN display looked significantly longer at the SG than the CG display during posthabituation-test trials. Infants habituated to the LB and HN displays looked at the CG and SG displays, almost equally. In contrast, infants habituated to the HB display looked longer at the CG than the SG display. These results show that infants under 1 month of age can perceive the continuation of the grating behind the occluder, and that their visual completion on habituation displays can be evoked according to the interaction between the spatial frequency of the grating and the occluder height.