EFFECT OF NEOSTIGMINE, d-TUBOCURARINE AND CLINICAL CONDITION ON EVOKED ELECTROMYOGRAM FROM ORBICULARIS OCULI IN MYASTHENIA GRAVIS

In our previous report, evoked electromyograms of the orbicularis oculi muscle with repetitive stimulation given at frequencies of 5, 10, 20, 50 and 100 c/s were examined in myasthenia gravis. The amplitude of M-waves showed several specific changes against the stimulation frequencies employed. The patterns of the amplitude of M-waves appearing with each frequency could be classified into 3 types, Type I, Type II and Type III according to relation between the frequency of stimulation and decrease and/ or increase of M-wave amplitude. In the present study, the effect of neostigmine, d-tubocurarine and clinical condition on the various pattern of M-wave amplitude curve classified into above mentioned three types was examined.     

Biochemical and histological features of hepatitis G virus infection

To assess the biochemical and histological characteristics of hepatitis G virus (HGV) infection, we examined four patients who were infected with HGV only (HGV group), and compared them with 16 patients infected with both HGV and hepatitis C virus (HCV; HGV + HCV group) and 18 patients infected with HCV only (HCV group). Biochemical examination showed a significantly low level of serum alanine aminotransferase (ALT) in the HGV group, and that the gamma-glutamyl transpeptidase (γ-GTP)/ALT ratio in the same group was significantly higher than in the other two groups. Although all three patient groups had a similar degree of liver fibrosis, both the degree of periportal inflammation and total histological activity index were significantly lower in the HGV group than in the other two groups. Fibrous enlargement of the portal tract without lymphoid infiltration and thin fibrous septa was characteristically observed in the HGV group. No significant difference was found between the HGV + HCV group and HCV group. Our results suggest that biochemical and histological changes in HGV infection are very mild and quite different from those of HCV infection.     

A case of well-differentiated minute hepatocellular carcinoma with extrahepatic metastasis

A rare case of well-differentiated minute hepatocellular carcinoma (HCC) metastasizing to distant sites in a 77-year-old man with hepatitis C virus (HCV)-related cirrhosis is presented. Ultrasonography (US) disclosed a 9 mm hypoechoic lesion in segment seven (S₇) of the liver, although computed tomography (CT), magnetic resonance imaging (MRI) and angiography did not reveal any space-occupying lesion. Ultrasound-guided biopsy showed the histological features of well-differentiated HCC. A plain film of the abdomen and CT revealed osteolytic changes in the sacrum and the lumbar vertebra. Ultrasound-guided biopsy of the sacrum revealed well-to-moderately differentiated HCC metastasizing from the liver. Percutaneous ethanol injection therapy (PEIT) effected complete response and completely eliminated the abnormal findings on US. Three months after PEIT, metastasis to the thoracic vertebra was revealed by CT, despite negative α-fetoprotein-mRNA in serum. This is the first report describing a well-differentiated HCC with metastatic potential. Further studies may provide insights into metastasis of well-differentiated HCC.     

Teratogenic Effect of Tedral (Theophylline, Ephedrine, and Phenobarbital) on Cardiac Development in Chick Embryos

Abstract We employed the chick embryo in a comparative study of the effect of Tedral and theophylline on anatomical development. Tedral, which contains theophylline in combination with ephedrine and phenobarbital in the relative dose ratio of theophylline 33: ephedrine 6: phenobarbital 2, or saline for control was dropped onto the surface of the chorioallantoic membrane of 2, 3, 4 and 5-day-old chick embryos. In groups A (theophylline 0.015 M, ephedrine 0.0027 M, phenobarbital 0.0009 M) and B (theophylline 0.011 M, ephedrine 0.0020 M, phenobarbital 0.0007 M), 100% of embryos treated on the 5th day of incubation developed aortic aneurysms with associated cardiovascular malformations. In group C (theophylline 0.005 M, ephedrine 0.0009 M, phenobarbital 0.0003 M), 36.8% of embryos treated on the 5th day of incubation developed aortic aneurysms, and 73.7% of embryos had cardiovascular malformations. These data were compared with those obtained by using theophylline, ephedrine or phenobarbital alone. The commonest cardiovascular anomalies induced by Tedral were double-outlet right ventricle with ventricular septal defect. Aneurysms were larger in size and cardiovascular malformations were more complex in embryos exposed to Tedral than in those treated with theophylline alone. Complex cardiac defects produced by Tedral included transposition of the great arteries, double-outlet right ventricle with double-inlet left ventricle, and truncus arteriosus communis. A slit-like small ventricular septal defect was found in 9.5% of the ephedrine-treated (0.51 mg) chick embryo group and 9.1% in the control embryos. These data show: (1) theophylline, a major component of Tedral, produces cardiovascular anomalies in embryonic chick hearts; (2) there is synergy of all three drugs in Tedral; (3) the specific type of conotruncal defect depends on the timing of administration, e.g., truncus arteriosus communis was produced on day 4 of Tedral administration in chick embryos.     

Ganglioneuroma of left adrenal gland in a patient with Turner syndrome during growth hormone therapy

We report on a Japanese girl with Turner syndrome (45,XO) who developed ganglioneuroma of the left adrenal gland during growth hormone (GH) therapy. She had received GH replacement therapy from the age of 6.8 years. At the age of 10.3 years, abdominal ultrasonography revealed a mass which occupied the upper area of her left kidney. Computed tomography and magnetic resonance imaging of the abdomen showed a low density mass with a smooth surface located between the upper portion of the left renal vein and the pancreas. Microscopic examination resulted in a diagnosis of ganglioneuroma of the left adrenal gland. At present we cannot conclude that patients who have received GH replacement therapy are at higher risk for developing tumors compared to those without GH replacement therapy.     

Effects of ATP on Phosphoinositide Hydrolysis and Prostaglandin E2 Generation in Rabbit Astrocytes

Extracellular ATP secreted from stimulated nerves plays a role in neurotransmission. This study examined the effects of extracellular ATP on phospholipase A₂ and C signalling pathways in rabbit astrocytes. ATP caused prostaglandin E₂ (PGE₂) generation and phosphoinositide hydrolysis in a time- and concentration-dependent manner. A P_2y purinoceptor-selective agonist, 2-methylthio-ATP also caused phosphoinositide hydrolysis, but not PGE₂ generation. A P_2x purinoceptor-selective agonist, α,β-methylene-ATP did not cause either phosphoinositide hydrolysis or PGE₂ generation. Although pertussis toxin had no effect on 2-methylthio-ATP-induced phosphoinositide hydrolysis, it markedly decreased ATP-induced PGE₂ generation, with significant inhibition of phosphoinositide hydrolysis. Dexamethasone and indomethacin which potently inhibited ATP-induced PGE₂ generation, caused partial inhibition of phosphoinositide hydrolysis, suggesting that pertussis toxin-sensitive component of ATP-induced phospholipase C activation is mediated by cyclo-oxygenase metabolites of arachidonic acid. These results suggest that a stimulation of P_2y receptor results in phospholipase C activation in a pertussis toxin-insensitive manner, and that a P₂ receptor other than the P_2y or P_2x subtypes is involved in ATP-induced phospholipase A₂ activation via a pertussis toxin-sensitive G protein.