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Aims

To analyse the histo-morphology of cases of medullomyoblastoma and identifying its divergent differentiation.

Methods

A retrospective review of all cases reported as medulloblastoma between the period of Jan 2000 to Dec 2006 was carried out on Hematoxylin and eosin (H & E) stained slides. The cases were screened on light microscopy for primitive neuroectodermal component of a medulloblastoma accompanied by areas of "myoid" differentiation, identified on the basis of presence of strap cells (indicating a clear skeletal muscle differentiation) and/or large anaplastic cells with vescicular nuclei and moderate to abundant amount of eosinophilic cytoplasm. All these cases were subjected to a panel of immunohistochemical stains, including Desmin, GFAP, NFP, HMB45, SMA, S100, CK and EMA. Ultrastructral analysis was done on tissue obtained from paraffin blocks in 2 cases.

Results

Male predominance (M:F = 5:1) was noted with an incidence of five percent of all cases of medulloblastoma (6 out of 120 cases) over a period of 6 years. Primitive neuroectodermal areas were accompanied with areas of "myoid" differentiation, 5 cases showing strap cells. Two cases with epithelial and cartilaginous differentiation were seen. Three cases showed focal melanocytic differentiation, identified only on HMB45 immunostaining. Four cases showed glial differentiation. Neuronal differentiation again was very focally seen in two cases, of which one was identified only by NFP immunostain. Seventh case is included in the study, however it is not considered to calculate incidence as it occurred beyond the period of 6 years of records search.

Conclusion

Medullomyoblastoma is a rare childhood tumor of cerebellum. Majority of cases reveal divergent differentiation, which are identified with the help of panel of immunostains indicating multi-potential nature of primitive neuroectodermal cells.  相似文献   
34.
Rumen microorganisms are responsible for digestion and utilization of dietary feeds by host ruminants. Unconventional feed resources could be used as alternatives in tropical areas where feed resources are insufficient in terms of quality and quantity. The objective of the present experiment was to evaluate the effect of diets based on palm oil (PO), decanter cake (DC) or palm kernel cake (PKC) on rumen total bacteria, selected cellulolytic bacteria, and methanogenic archaea. Four diets: control diet (CD), decanter cake diet (DCD), palm kernel cake diet (PKCD) and CD plus 5% PO diet (CPOD) were fed to rumen cannulated goats and rumen samples were collected at the start of the experimental diets (day 0) and on days 4, 6, 8, 12, 18, 24 and 30 post dietary treatments. Feeding DCD and PKCD resulted in significantly higher (P<0.05) DNA copy number of total bacteria, Fibrobacter succinogenes, Ruminococcus flavefeciens, and Ruminococcus albus. Rumen methanogenic archaea was significantly lower (P<0.05) in goats fed PKCD and CPOD and the trend showed a severe reduction on days 4 and 6 post experimental diets. In conclusion, results indicated that feeding DCD and PKC increased the populations of cellulolytic bacteria and decreased the density of methanogenic archaea in the rumen of goats.  相似文献   
35.

Background  

The main morphological features of primitive cells, such as stem and progenitor cells, are that these cells consists only one nucleus. The main purpose of this study was to determine the differentiation capacities of stem and progenitor cells. This study was performed using mononucleated cells originated from murine peripheral blood and MC3T3-E1 cells. Three approaches were used to determine their differentiation capacities: 1) Biochemical assays, 2) Gene expression analysis, and 3) Morphological observations.  相似文献   
36.
Aspergillus funiculosus was isolated from rotted banana fruits, whereas Alternaria tenuis and Fusarium sp. were isolated from rotted tomato fruits. The isolated fungi tolerated relatively high levels of the fungicide, Dithane, up to 2560 ppm on solid medium, but grew well at 40 ppm when supplemented with liquid medium. They are able to tolerate selenite up to 2% (w/v) sodium selenite. A. funiculosus showed no growth in the presence of mixture of 2.5 ppm selenium and 20 ppm Dithane, whereas Fusarium sp. failed to grow at 2.5 ppm selenium and 10 ppm Dithane, or at 10 ppm of each. Nevertheless, Alternaria tenuis is more tolerant; it showed growth in the presence of relatively high levels of selenium and Dithane; up to 10 ppm selenium and 40 ppm Dithane, however, its growth was inhibited by the presence of a mixture of both. The results suggested new form of highly active fungicides. Selenium as an essential nutrient at such very low concentrations, as well as the application of very low concentrations of the fungicide, would certainly reduce the hazardous effect of such pollutant in the environment.  相似文献   
37.
A house to house random survey on elderly subjects was undertaken in the District of Klang in Malaysia. The objective of this study was to investigate the prevalence of oral mucosal lesions (OML) among the elderly in this area. The primary units in the sampling frame were the Enumeration Blocks (EBs) as defined under the population census. All households of the selected EBs were considered as sampling units and members aged 60 and above were considered as respondents. There was a slight preponderance of females, with the Malays comprising the majority of the subjects. Of the 486 respondents, mean aged 69.1 ± 7.3 yr, 111 had at least one oral mucosal lesion, a prevalence of 22.8%. A total of 145 lesions were detected. The prevalence of OML was highest among Indians and least among the Chinese. The most common finding was tongue lesions, recording a prevalence of 10.7%, followed by oral pigmentation (4.9%) and white lesions (4.3%). Denture related lesions were comparatively low at 2.5%. Two cases of oral cancer if representative would give a relatively high prevalence of 0.4%.  相似文献   
38.
Roots and aerial shoots ofZygophyllum coccineum L.,Z. album L. andZ. dumosum Boiss were extracted with solvents of increasing polarity and tested against spore germination ofVerticellium albo-atrum andFusarium oxysporum f.sp.lycopersici. The effectiveness of each extract depends on the solvent, plant species, organ and test fungus. Petroleum ether extracts were ineffective as fungistatics while the methanol extracts possessed a high inhibitory effect toward spore germination suppression, depending on the fungus and plant species. Water or ethyl acetate root extracts ofZ. album caused a marked suppression of spore germination of the test fungi. Six saponins were isolated from the effective extracts on silica gel and Sephadex columns. They were identified by acid hydrolysis, alkaline saponification, IR and FAB MS. Quinovic acid was the dominant aglycone. Kaempferol was isolated from the flavonoid fraction ofZ. dumosum for the first time. Some of the isolated saponins and kaempferol provided successful control against the test plant pathogens under greenhouse experiment when used as seed treatment.  相似文献   
39.
Prototheca wickerhamii isolated from blood of 61-year-old kidney transplant patient was described. Although it is classified as an alga (genus Chlorella), the disease, protothecosis, is included under mycoses because of its clinical pathological presentations. Colony characteristics of P. wickerhamii are indistinguishable from other yeast-like organisms like Cryptococcus and Candida. Fortunately, commercial identification system for yeast can be used to identify this organism to the species level. Electron microscopy demonstrated "morula" or daisy-like appearance of its endosporulating sporangia. The organism was sensitive to amphotericin B by E test method. Even though human protothecosis is uncommon, it cannot be ignored because it is emerging as an opportunistic infection in immunosuppressed individuals. To our knowledge, this is the first reported case of disseminated algaemia due to P. wickerhamii in Malaysia.  相似文献   
40.
Summary Heat treatment (10 min at 65° C) of cells of Alcaligenes eutrophus, which resulted in the release of RNA degradadation products into the medium, was found to activate cellular ribonucleases. Two ribonucleases degrading yeast RNA were found, one localized in the periplasmic space and the other in the soluble fraction of the ribosomes. Compared to non-heated cells, in the heat-treated cells the former enzyme, the cell debris ribonuclease, was present at an eightfold increased specific activity, and the latter, the cytoplasmic ribonuclease, was present at a fourfold increased specific activity. This increase was due to the inactivation of a thermolabile inhibitor and to denaturation of part of the soluble protein during heat treatment. With respect to their properties the enzymes were similar; they had endonuclease activity and hydrolysed only RNA. They were heat-stable, resistent to trypsin, highly sensitive to a ribonuclease inhibitor isolated from the same bacterium and were partially inhibited by ATP and GTP. These properties provided a partial explanation for the mechanism of the release of RNA dagradation products from A. eutrophus cells after heat treatment.Abbreviations DNA Deoxyribonucleic acid - RNA Ribonucleic acid - tRNA Transfer RNA - DNase Deoxyribonuclease - RNase Ribonuclease - d-RNase debris RNase - c-RNase cytoplasmic RNase  相似文献   
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