Fulminant sepsis-associated encephalopathy in two children: serial neuroimaging findings and clinical course.

We report on two children with sepsis-associated encephalopathy. They presented with fulminant neurological damage on clinical, neuroimaging, and neurophysiological findings. At onset, both went into deep coma after status epilepticus, resulting in near brain death. Both patients showed diffuse brain edema on CT and severe brain dysfunction on electroencephalography within a day of onset. Brain magnetic resonance (MR) imaging of one patient on day 2 showed restricted diffusion in the basal ganglia and the subcortical white matter of the frontal and occipital lobes. Brain edema aggravated and lasted for a few months despite a variety of treatments. MR imaging in the chronic phase revealed cracking lesions extending to the cerebral white matter, the cerebellum, and the brainstem. MR angiography showed diminished intracranial major arteries. These serial neuroradiological findings suggested severe brain damage resulting from fulminant elevation of intracranial pressure, which mimicked "brain death" or "respirator brain".

Late-onset neuropsychological symptoms in a Japanese patient with megalencephalic leukoencephalopathy with subcortical cysts.

We herein report a Japanese patient with megalencephalic leukoencephalopathy with subcortical cysts (MLC) who developed late-onset neuropsychological symptoms. He demonstrated characteristic clinical features of MLC during childhood, such as slowly progressive megalencepaly, motor impairment with ataxia and spasticity, mild mental retardation, and well-controlled epilepsy. Thereafter, he showed specific neuropsychological symptoms, such as motor and vocal tics, compulsive behavior, perseveration, acquired stuttering, and dystonia since the age of 12. His performance abilities had been unchanged but his verbal abilities had degraded during the past 14 years. Higher cortical dysfunction tests revealed a frontal lobe dysfunction. On repeated brain MRI, a leukoencephalopathy with subcortical cysts remained stationary from infancy. On single photon emission computed tomography (SPECT), a hypoperfusion in the frontal lobe was detected at the age of 3.5 and 17, but the severity of hypoperfusion was also unchanged, respectively. Our results indicate that the frontal lobe dysfunction may be relevant to the late-onset neuropsychological symptoms with MLC.

Transcript profiling in plastid arginine tRNA-CCG gene knockout moss: construction of Physcomitrella patens plastid DNA microarray.

The moss Physcomitrella patens is a newly established model plant that is widely used for the characterization of gene function by targeted gene knockout or over-expression. The target gene disruption occurs in both the nuclear and chloroplast genomes. We applied DNA microarray technology to the P. patens plastid genome for large-scale analysis of transcripts. A microarray was constructed containing 108 DNA fragments to detect all annotated plastid genes. We analyzed the transcript profile in a knockout transformant for the arginine tRNA gene, trnR-CCG, and confirmed previous results that rbcL and psaI transcripts accumulate in similar levels to wild-type moss, and accD transcript level is higher than those of wild-type moss. Additionally, the plastid DNA microarray revealed that most plastid genes were expressed at similar levels in wild-type and transformant mosses. This indicates that trnR-CCG is not essential for the expression of plastid genes.

Development of squamous cell carcinoma from pre-existent oral leukoplakia: with respect to treatment modality.

The present study was undertaken in order to determine whether surgical treatment of oral leukoplakia reduces the risk of the subsequent development of carcinoma. This study included 142 patients with oral leukoplakia who received or did not receive surgical treatment. All subjects were followed-up for more than 6 months with a mean follow-up period of 4 years. Malignant transformation rate was lower among patients who received surgical excision (1/75) than among those who did not receive surgical treatments (4/51). However, the malignant transformation rates were high in patients who received cryosurgery (3/12) or cryosurgery plus surgical excision (1/4). There was no obvious relation between the grade of epithelial dysplasia and the rate of malignant transformation. Our results suggest that surgical excision of oral leukoplakia may reduce the risk of the subsequent development of carcinoma.

A Japanese girl with leukoencephalopathy with vanishing white matter.

A Japanese girl with peculiar leukoencephalopathy was reported. Following normal development until 1 year of age, she showed progressive neurological deterioration with ataxia, epilepsy, pyramidal tract signs and choreic movement. Serial brain computed tomographies (CTs) revealed markedly low density and progressive volume loss in whole white matter. In extensive laboratory investigations, the level of glycine in the urine was elevated. She died at the age of 4 years, and the neuropathological findings were comprised of severe extensive changes in cerebral and cerebellar white matter, such as marked rarefaction or cystic degeneration with axonal loss. The pontine central tegmental tracts were also affected. Neuronal loss was seen in the cerebellar cortex. These features were compatible with leukoencephalopathy with vanishing white matter, which was recently established as a clinical entity. To our knowledge, this is the first report of a non-Caucasian patient with this new type of leukoencephalopathy.

High malignant transformation rate of widespread multiple oral leukoplakias.

OBJECTIVE: This study was undertaken in order to investigate clinicopathologic characteristics and malignant potential of widespread multiple oral leukoplakias. PATIENTS AND METHODS: The present study includes 12 patients with widespread multiple leukoplakias (widespread patients) and 99 with localized lesions (localized patients), and all patients were followed for more than 6 months with the mean follow-up period of 4 years. RESULTS: Gingiva and tongue were the major affected sites of leukoplakias in the localized patients, whereas gingiva and buccal mucosa were predominantly affected in the widespread patients. The rate of developing carcinoma was significantly (P < 0.02) higher in the widespread patients (3/12) than in the localized patients (5/99), although there was no significant difference in the rate of dysplastic lesions between these groups. CONCLUSION: These results indicate that the widespread leukoplakias have a higher potential for the development of carcinoma than do the localized lesions.

Characteristics of mutations in the p53 gene of oral squamous-cell carcinomas associated with betel-quid chewing in Sri Lanka.

Oral squamous-cell carcinoma (SCC) is the most common neoplasm in Sri Lanka, accounting for approximately 30% of all cancers in males. Epidemiologic evidence indicates that there is an unequivocal relationship between betel chewing and oral carcinogenesis, suggesting that there may be specific genetic targets of betel-quid ingredients. The p53 gene has been indicated to be a tumor-suppressor gene that is found in mutated form in common human cancers; however, there are few reports about "carcinogen-specific" p53 mutation. Because of this background, primary resected specimens from 23 oral SCCs, 7 leukoplakias and 2 oral submucous fibrosis were collected from oral SCC patients in Sri Lanka and were used for p53 mutation analysis. Exons 5 through 8 of the p53 gene were examined by polymerase chain reaction-single-strand conformation polymorphism (PCR-SSCP) and direct sequencing. Mutations in the p53 gene were frequent (10/23) in oral SCC specimens from Sri Lanka. Moreover, the mutations clustered significantly in exon 5 (7/10) of the p53 gene, and small deletions and inclusions other than point mutations were observed. These results indicate that 1) betel-quid chewing may cause specific genetic changes, including mutation in the p53 gene; 2) mutations in the p53 gene are not rare events in SCC patients who are betel-quid chewers, which contrasts with other reports; 3) exon 5 of the p53 gene could be one of the specific targets for some betel-quid ingredients; and 4) betel-quid chewing may be a critical environmental factor in the development of oral SCC.

[Xenogenization of rat tumor cells by transfection with envelope gene derived from Friend murine leukemia virus].

The highly tumorigenic rat hepatocellular carcinoma cell line cKDH-8-cl-11 was xenogenized by transfection with an envelope (FV-env) gene derived from Friend murine leukemia virus. The transfected tumor cells, expressing the FV-env gene product on the cell surface, were injected into normal and immunosuppressed (irradiated) syngeneic rats. All the irradiated rats developed tumors at the injection site. Thirteen out of fifteen normal rats rejected the xenogenized cells and acquired tumor transplantation resistance to the parent (nontransfected) cell line. The tumor cells that grew in normal rats failed to express th FV-env gene product during growth in vivo, but resumed expression during in vitro primary culture. These results suggest that the FV-engine product, when expressed on tumor cell surfaces, displays biological characteristics which are immunologically recognized by normal rats and induces tumor rejection. Moreover the results show that the FV-env gene product is a good candidate for the xenogenization of tumor cells.

Xenogenization of tumor cells by transfection with plasmid containing env gene of Friend leukemia virus.

A rat hepatocellular carcinoma cell line (cKDH-8 cl-11) showed decreased tumorigenicity after transfection with an envelope gene derived from a Friend leukemia virus (FV-env gene). FV-env gene product was found by indirect immunofluorescence staining to be expressed on the cell surface of the FV-env gene-transfected cells. The FV-env-transfected cells (FV-env cKDH-8), however, grew well in X-irradiated immunosuppressed rats, indicating that the reduction in tumorigenicity of the transfected cells is based on immunological reaction in the host. The rats which rejected FV-env cKDH-8 cells showed resistance to rechallenge with the parent cKDH-8 cl-11 tumor cells. These results suggest that the FV-env gene product may elicit antitumor immunity against FV-env cKDH-8 cells in a host with a resultant reduction in the tumorigenicity of these cells.