The effects of cortical ablation on mastication in the rabbit

To verify the hypothesis that the control of movement by the cortical masticatory area (CMA) is particularly important at the beginning of the mastication, we compared movements before and after bilateral CMA ablation. After ablation, the animal could not manipulate food placed in the front of the mouth for several days. With further recovery, the animals could masticate in a more normal way, but the times taken to manipulate the food and to chew to the point of swallowing were increased. However, the form and amplitude of the masticatory cycles were only slightly changed by loss of cortical control. The results indicate that CMA is of great importance at the beginning of mastication and probably also in terminating chewing and initiating swallowing.     

Cleidocranial dysplasia: a light microscope, electron microscope, and crystallographic study

An unusual case of cleidocranial dysplasia associated with more than 60 unerupted teeth is presented and examined with light and scanning electron microscopes and crystallographic techniques. The present case revealed pseudoprognathism with facial asymmetry, the right side being larger than the left. The extracted teeth showed enamel hypoplasia in light and scanning electron microscopy, yet the crystalline composition did not differ from that of the normal teeth. The potential causes of lack of eruption and supernumerary tooth formation in cleidocranial dysplasia are discussed.     

Acute myelogenous leukemia accompanied by HTLV-I associated myelopathy (HAM) caused by blood transfusion

A case of AML accompanied by HTLV-I associated myelopathy (HAM) is reported. A 37-year-old woman was admitted to our hospital in April 1985 because of severe anemia, general malaise and fever. On admission, anemia, thrombocytopenia and leukocytosis consisting of 32% myeloblasts and 6% promyelocytes were noted. A bone marrow study revealed marked myeloid hyperplasia, and a diagnosis of acute myelogenous leukemia (M2) was made. In order to improve the patient's severe anemia and thrombocytopenia, a large amount of blood transfusion was applied at once. Thereafter BHAC-DMP therapy was commenced resulting in complete remission 3 months after initiating chemotherapy. Hematological improvement has continued (as of May 1988). In June 1986 the patient showed a gait disturbance of slowly progressive course. Neurological examination revealed hyperactive knee and ankle jerks with a positive Babinski's sign, and foot clonus were also noted bilaterally. Sphincter impairment was detected. A CSF sample contained slight pleocytosis with some abnormal lymphocytes similar to those found in adult T cell leukemia. Antibodies to HTLV-I were found in the CSF and serum by EIA method. According to these findings we diagnosed the patient's illness as HAM, referring to the new clinical entity named by Osame. This patient had undergone a blood transfusion 14 months before the onset of this myelopathy, therefore the transmission of exogenous antigens through blood transfusion may be the cause of HAM. Corticosteroid pulse treatment was administered and striking improvements countering gait disturbance resulted in this patient.     

Familial presumed cerebral cavernous angiomas diagnosed by MRI: three generations

Familial cerebral cavernous angiomas are rare, with an autosomal dominant pattern of inheritance. To our knowledge, 25 families with this disorder have been described. We report three family members in a direct line of descent, who all brain had lesions typical of cavernous angiomas on MRI. Received: 10 January 1995 Accepted: 4 October 1995     

Rapid inhibition of intercellular communication between BALB/c 3T3 cells by diacylglycerol, a possible endogenous functional analogue of phorbol esters

Intercellular communication between cultured cells is reversibly inhibited by phorbol ester tumor promoters, which have been shown to activate protein kinase C directly, replacing the role of diacylglycerol. In order to see whether a presumed endogenous functional analogue, a diacylglycerol, could inhibit intercellular communication in the same way as phorbol esters, we compared the effects of 1-oleoyl-2-acetyl-glycerol (OAG) and 12-O-tetradecanoylphorbol-13-acetate (TPA) on intercellular communication between BALB/c 3T3 cells, using a fluorescent dye transfer method. When cells were treated with OAG, dose-dependent inhibition of dye transfer between cells was observed, which was almost complete with OAG at 50 micrograms/ml. The effect was rapid, a maximal effect occurring within 30 min after addition. The inhibitory effect of both compounds was maintained for at least for 4 h when the cells were in the growing phase; thereafter, the capacity to transfer dye recovered gradually and then returned to the control level after 8 or 12 h of treatment with OAG or TPA, respectively. Further additions of OAG or TPA had no effect. When OAG was added to cultures during a refractory period produced by TPA, the culture was also refractory to OAG; however, TPA could induce at least 60% inhibition of dye transfer in cultures that had been made refractory to OAG. However, when cultures that had been made refractory to TPA were washed and then OAG was added, it induced extensive inhibition of dye transfer at any time after removal of TPA, whereas addition of TPA to the culture caused no significant reinhibition by 6 h and was detectable only 9 h after removal of TPA. These results indicate that OAG can inhibit dye transfer in a similar manner to TPA, suggesting that activation of protein kinase C may be a mechanism by which phorbol esters inhibit intercellular communication. Our results also suggest that there is some difference between the mechanisms by which OAG and TPA inhibit intercellular communication.