Argyrophilic grains in late-onset Creutzfeldt–Jakob diseased brain

Braak's argyrophilic grains (ArG) are spindle-shaped structures originally described in patients with dementia. Herein, a unique case of sporadic Creutzfeldt-Jakob disease (CJD) accompanied by numerous ArG is presented. The pathological picture was typical of CJD based on the findings of routine hematoxylin-eosin staining. The highest density of ArG was observed throughout the parahippocampal gyrus and the temporal gyri; however, the sector CA1 of the hippocampus showed less ArG. An immunohistochemical analysis for prion protein (PrP) revealed diffuse fine neuropil staining in the cerebral cortex, while the ArG themselves did not demonstrate any immunoreaction for PrP. No correlation was observed between the densities of ArG and either the presence of senile plaques, neurofibrillary tangles or neuropil threads in the present case. To our knowledge, this is the first report of CJD demonstrating numerous ArG.     

Clinical, radiological and histopathological studies of squamous cell carcinoma of lower gingiva]

In order to improve the treatment results of the lower gingival carcinoma, the treatment results were analysed based on the X-ray views, histopathological findings and mode of treatment. A series of 152 cases of primary lower gingival carcinomas treated at the First Department of Oral and Maxillofacial Surgery, Tokyo Medical and Dental University, during the 25 years between 1964 and 1988 was surveyed. The lesions with the invasive type of bone resorption on the X-ray picture often had unclear tumor margin histopathologically and those of the pressure type had a smooth front, with a small number of exceptions. The five-year cumulative survival rate was 76.7% for the pressure type, 64.6% for those without bone resorption, 53.9% for the invasive type. The deeper the resorption was, the higher the death rate was in the invasive type. Grade II of WHO classification and Grade 3 of the mode of invasion had the least recurrence rate and the least frequency of delayed cervical metastases. Grade 4D showed the highest recurrence rate and Grade 4C a high frequency of cervical metastases. Five-year cumulative survival rate was 77.8% for the cases treated by surgery, 65.6% for those by the combination of surgery and radiation, 57.1% for those by chemotherapy and 29.5% for those by radiation.     

Scanning electron microscopy of eggs of Mansonia uniformis, Ma. indiana, Ma. annulifera, and Ma. annulata (Diptera: Culicidae).

The eggs of Mansonia uniformis, Ma. indiana, Ma. annulifera, and Ma. annulata are described with the aid of scanning electron micrographs. Comparisons of egg structure among the four species showed that the eggs differed discernibly with respect to the outer chorionic tubercles on the anterior tube, the spines surrounding the raised central micropyle within the anterior cup, and the outer chorionic tubercles in the posterior region. Attempts to produce a key for identification of these eggs under scanning electron microscopy are discussed.     

Rosenthal fibers and glial filaments associated with hemidesmosome-like structures in perivascular astrocytes in a juvenile form of Alexander's disease

We present a rare case of Alexander's disease occurring in a 10–year-old girl with convulsive seizures. She initially developed gait disturbance and thereafter deteriorated mentally. At 48 years of age she died of cumulative convulsive seizures. The postmortem examination revealed a generalized and focally pronounced deposition of Rosenthal fibers in the deep cerebral white matter around the lateral ventricles. Atypical fibrillary glia, diffuse patchy demyelination and circumscribed cystic necrosis were also observed. An electron microscopic examination of the cerebral white matter revealed not only irregular, densely osmiophilic bodies merging in places with glial filaments, but also well-developed hemidesmosomes associated with anchorage densities in the perivascular astrocytes. The subplasmalemmal anchorage densities usually received glial fibrils, which were frequently intermingled with Rosenthal fibers. Thus, our case can be added to the small number of previously reported cases demonstrating a juvenile form of Alexander's disease based on both clinicopathologic features and on ultrastructural appearance, and our case also confirms the profound involvement of astrocytes.     

Enhancement of percutaneous absorption by laurocapram.

The in vitro treatment of shed snake skin and hairless rat skin with laurocapram resulted in dramatic decreases in the amounts of cholesterol, phospholipids, and ceramides but not triglycerides in the skins. Scanning electron microscopic observations of hairless rat skin treated with laurocapram indicated looseness and cell separation of the stratum corneum probably caused by the extensive extraction of the intercellular lipids. An ESR study demonstrated the increased fluidity of the corneum lipids after laurocapram treatment. The apparent rotational correlation time of 16-doxyl-stearic acid was decreased by 1.6-2 times after treatment with laurocapram. No penetration of laurocapram itself through shed snake skin and hairless rat skin was detected in vitro, except when the reservoir solvent was 60% ethanol or propylene glycol. The enhancer was hardly metabolized during a 48-h incubation with skin homogenate. Pretreatment of shed snake skin with laurocapram increased significantly the penetration of sulfanilamide and indomethacin through the skin. These results indicate that laurocapram penetrating into the stratum corneum interacts with structured lipids in the intercellular channels and releases them, thereby enhancing the penetration of hydrophilic drugs through the channels. Additionally, laurocapram penetrating into the intracellular matrix of the corneum fluidizes the intracellular lipids and causes the reduction of diffusional resistance.     

Epithelial properties of pleomorphic xanthoastrocytomas determined in ultrastructural and immunohistochemical studies

Summary Three cases of pleomorphic xanthoastrocytoma (PXA), one of which showed anaplastic evolution, are described. In all three the PXA tumors were well circumscribed and could be totally removed. Light-microscopically, pleomorphic tumor cells clustered gregariously and often formed alveolar structures. Electron microscopy revealed various epithelial properties, such as junctions and interdigitations between apposing tumor cells, and prominent basal laminae surrounding tumor nests. The circumscribed growth of PXA, as contrasted with an infiltrative growth of usual astrocytoma, can be attributed to the cellular cohesion based on the epithelial properties of the tumor cells. In the third patient, tumor recurred 6 months postoperatively. Although the recurrent tumor retained the alveolar structures, pleomorphism and various degenerative features of the tumor cells diminished with advance in the proliferative activities.Supported in part by grant in aid 60480328 from the Ministry of Education, Science, and Culture, Japan