Hereditary angioedema caused by a point mutation of exon 7 in the Cl inhibitor gene

Summary Hereditary angioedema (HAE) is a genetic disease which may be detected serologically. We present a patient with HAE in whom we examined the gene defect using the polymerase chain reaction. The patient presented with recurrent episodes of abdominal pain, or non-itchy swellings of the hands, feet, and penis. The serum levels of C1 inhibitor (C1-INH and C4 were below normal. We determined that a single base change (C-T) at nucleotide 1482 in the seventh exon was present in the C1-INH gene. This mutation converted the codon for the Gln-339 to a premature translation termination codon TAG. A point mutation in the C1-INH gene can cause type I HAE.     

Longitudinal study on occlusal force distribution in lower distal-extension removable partial dentures with conus crown telescopic system

The purpose of this study was to examine longitudinal changes of the occlusal force distribution in lower distal-extension removable partial dentures with the conus crown telescopic system. Occlusal force applied to the denture and forces transmitted to the retainers were measured on several separate occasions from the insertion of new dentures to about 3 months after. The occlusal force distribution ratio to the retainers was calculated when a load of 20N was applied to the denture.
The results are summarized as follows:

• (i)

    The more posterior the loading point of occlusal force, the smaller was the ratio. When the occlusal force was applied to the most anterior artificial tooth, the ratio was 65-100% of the occlusal force.
• (ii)

    As the denture wearing time proceeded, the ratio was decreased. The smaller the ratio, the greater was the rate of its decrease.

     

氧化型脂蛋白(a)和冠心病的相关性研究

目的探讨氧化型脂蛋白(a)和冠心病的相关性。方法行择期冠状动脉造影术的患者366例,于术前采血测定血清脂蛋白(a)和氧化型脂蛋白(a)的含量。结果冠心病组患者的脂蛋白(a)含量(90.5 mg/L),明显高于非冠心病组(64.0 mg/L),差异有统计学意义(P<0.05);冠心病组的氧化型脂蛋白(a)含量(0.09 nmol/L)亦明显高于非冠心病组(0.05 nmol/L),差异有统计学意义(P<0.05);但仅氧化型脂蛋白(a)与冠状动脉病变的Gensini评分相关(r=0.122,P<0.05)。多变量逐步logistic回归分析显示年龄(P<0.01)、男性(P<0.01)、糖尿病(P<0.01)、高脂血症史(P<0.01)、低高密度脂蛋白血症(P<0.01)及血清氧化型脂蛋白(a)含量的上四分位(P<0.05)是冠心病的独立危险因素。结论氧化型脂蛋白(a)而非脂蛋白(a)是冠心病的独立风险因子。     

Dermatofibrosarcoma protuberans is a unique fibrohistiocytic tumour expressing CD34

Dermatofibrosarcoma protuberans (DFSP) is a slow growing, locally invasive tumour whose differentiation from other fibrohistiocytic tumours sometimes poses serious diagnostic problems. We investigated CD34 expression immunohistologically in various fibrohistiocytic tumours including dermatofibroma, DFSP, malignant fibrous histiocytoma (MFH), infantile myofibromatosis, fibrosarcoma, hypertrophic scar and keloid. Among these, DFSP was unique in that tumour cells themselves expressed CD34, whereas in other tumours. CD34 expression was observed only on vascular endothelial cells amongst the tumour cells. Until now, there have been no reports of useful immunohistological markers for DFSP. CD34 expression by the tumour cells can be an extremely useful marker in establishing a definitive diagnosis of DFSP.     

THE IMMUNOHISTOCHEMICAL DEMONSTRATION OF SUBSEQUENCES OF THE PRECURSOR OF THE AMYLOID A4 PROTEIN IN SENILE PLAQUES IN ALZHEIMER''S DISEASE

The actual presence of the predicted precursor of Alzheimer's disease amyloid A4 protein, reported by Kang et al. (1987) in the Alzheimer brain, has yet to be verified. To identify the various regions of this precursor, antibodies were raised against three synthetic polypeptides, R35 (residues 274-286), R36 (residues 527-540), and R37 (residues 681-695), subsequences of the precursor protein; the specificity of these antibodies was ascertained by ELISA. Upon immunohistochemical examination, the antibody to R35 failed to react, but the antibody to R36 (the extracellular part) stained the amyloid of senile plaques and the staining pattern was identical to that of anti-A4 antibody. The antibody to R37 (the C-terminal intracellular part) stained what may be degenerating neurites in senile plaques whereas the amyloid remained unstained. An anti-neurofilament (NF) antibody reacted with some of the R37-positive grains, but R37-negative grains also were seen. Further, some R37-positive grains were not stained by the anti-NF antibody. The anti-GFAP antibody and the anti-macrophage antibody did not stain the R37-positive grains. These findings indicate that the amyloid protein in senile plaques actually contains a larger polypeptide than the A4 protein, and suggest that the intracellular C-terminal part of the precursor may exist in the degenerated neurites seen in senile plaques.     

EARLY SENILE PLAQUES IN DOWN''S SYNDROME BRAINS SHOW A CLOSE RELATIONSHIP WITH CELL BODIES OF NEURONS

A sensitive methenamine silver/Nissl stain was used to study the morphology and relationship of pre-plaques (presumed early senile plaques) in Down's syndrome brains to glial nuclei, capillaries and neuronal perikarya. The larger pre-plaques (greater than 50 microns) usually encompassed all of these tissue elements. However, the smaller pre-plaques (less than or equal to 50 microns) were almost always found immediately adjacent to, or around the cell bodies of neurons (often with associated satellite cells), and they failed to show any consistent, close spatial relationship to the other tissue components. Thus we consider an early stage of pre-plaque formation to be the deposition of amyloid adjacent to the cell body of a morphologically normal neuron. Based on the study of transitional forms, we suggest that the amyloid progressively accumulates around the cell body until the enclosed neuron degenerates. How these pre-plaque lesions might eventually develop into the typical plaque structure is uncertain. Our observations support the theory of a neuronal origin for plaque amyloid.     

Susceptibility of experimental autoimmune hepatitis in transgenic mice overexpressing the c-H-ras gene

Results from a recent study of ours have demonstrated the significant role of the wild-type ras gene in the development of hepatocellular carcinoma in rasH2 mice having prototype human c-H- ras genes. Chronic cell death and regeneration have been considered to work as co-carcinogens with wild-type ras gene overexpression in this model. To elucidate a role of gene overexpression in the occurrence of chronic inflammation, we tried to induce inflammation in the liver of rasH2 mice by immunizing them with the supernatant of a freshly prepared syngenic liver homogenate. Immunization resulted in a dense inflammatory infiltrate in the portal tract and focal necrosis with spots of fatty or foamy degeneration in the transgenic mouse liver; however, these observations were less frequently observed in non-transgenic mouse liver. Monocytes, granulocytes and plasma cell infiltration were observed in the livers of transgenic mice. An immunohistochemical study showed that CD3-positive lymphocytes also infiltrated the liver. The inflammatory infiltrate was still present in the transgenic liver 24 weeks after the last injection, but little infiltrate was observed at the same time in non-transgenic mice. No hepatic tumours could be produced over the 6 months duration of the study and the results are only preliminary. However, these results do suggest that overexpression of wild-type ras is partially responsible for the occurrence of autoimmune chronic hepatitis.     

Congenital malignant melanoma

A case is reported of congenital malignant melanoma that occurred in the absence of maternal melanoma or a congenital giant naevus. The patient had the melanoma on the left thigh excised 54 days after birth, but later died at the age of 18 months with multiple metastases.     

Effects of colchicine on the induction of ornithine decarboxylase and its gene expression by the phorbol ester tumour promoter

The activity and gene expression of ornithine decarboxylase (ODC, an indicator of tumour promotion) were induced by the phorbol ester tumour promoter, 12-O-tetradecanoylphorbol-13-acetate (TPA), in mouse skin. In the present study, the effect of colchicine, a microtu-bule-disrupting agent, on ODC activity and its gene expression were investigated. On administration of colchicine (100 μg) intraperitoneally 1·5 h before TPA treatment, ODC activity and ODC mRNA levels stimulated by TPA were suppressed to about 52 and 64%, respectively. These results suggest the involvement of a microtubule or colchicine-sensitive substrate in the signal transduction system for gene expression.