Behavioral changes after focal cerebral ischemia by left middle cerebral artery occlusion in rats

Behavioral changes after occlusion of the left middle cerebral artery (MCA) in rats were investigated for 16 weeks. Impairment of motor coordination and incidence of neurological deficits including hemiplegia and abnormal posture were present for the first 2 and 4 weeks after MCA occlusion, respectively. Learning behavior in one-trial passive avoidance task was disturbed for the entire 16-week period when rats were trained at days 3 after MCA occlusion. Reacquisition was also impaired when rats were retrained on 8 weeks after MCA occlusion. Except for synchronized EEG at days 2 after MCA occlusion, significant changes in spontaneous movement and EEG were not observed in the MCA-occluded group. These results suggest that this rat model of MCA-occlusion is useful for quantitatively measuring functional changes in chronic phase of focal cerebral ischemia.     

Vocal cord abductor paralysis (VCAP) in Parkinson''s disease: difference from VCAP in multiple system atrophy

Vocal cord abductor paralysis (VCAP) is rare in Parkinson's disease (PD), while it is frequent in multiple system atrophy (MSA). Although VCAP is a life-threatening complication it has not yet been clarified whether there is any difference in the mechanism of VCAP between PD and MSA. Examining 3 autopsy-proven PD patients who developed severe VCAP requiring tracheostomy, we found the following differences in the mechanism of VCAP between MSA and PD: (1) clinical and laryngofiberscopic examination showed that VCAP in PD was not exacerbated during sleep, unlike in MSA; (2) On histological examination of the intrinsic laryngeal muscles, the posterior cricoarytenoid muscle demonstrated no abnormalities in PD, while the muscle showed characteristic neurogenic atrophy in MSA. There seemed to be two types of VCAP, namely the nonparalytic type observed in PD, and the paralytic type observed in MSA. Severe dysphagia requiring tube-feeding was common among PD patients who presented with VCAP. Although the relationship between VCAP and dysphagia is unknown, one should be aware of the possibility of fatal VCAP in PD patients with severe dysphagia.     

Thyroid involvement by malignant histiocytosis of Langerhans' cell type

Involvement of the thyroid gland by Langerhans' cell histiocytosis is quite rare. We describe the case of a 58-year-old man referred for treatment of a progressively enlarging goitre. The trachea was severely stenotic and adjacent structures such as the left carotid vein and the thyroid cartilage were also involved. Central diabetes insipidus and severe combined immunodeficiency were associated. Although fine needle aspiration biopsy of the thyroid was initially interpreted as papillary carcinoma, anaplastic thyroid cancer was suspected. Treatment with prednisolone, doxorubicin and irradiation controlled the tracheal compression. A diagnosis of thyroid Langerhans' cell histiocytosis was finally made on the basis of the presence of Birbeck granules and CD1a and CD4 antigen in the thyroid tumour cells. Furthermore, positive staining for CD68 and lysozyme suggested that the tumour cells may have had the character of phagocytic cells in addition to their dendritic cell nature. This is the first case of thyroid involvement by malignant histicytosis of Langerhans' cell type with unusual phagocytic markers.     

Study on transfer of ceftriaxone into female genital organs

One gram of ceftriaxone (Ro 13-9904, CTRX), a new cephalosporin antibiotic, was given intravenously to a total of 25 patients prior to abdominal total hysterectomy for uterine myoma with or without small benign ovarian tumor. Bilateral uterine arteries were clamped at 0.5, 1, 2, 6, 12 and 24 hours after administration, and serum samples and uterine tissues were taken for the measurement of CTRX concentration by bioassay method. A little difference was found in the serum concentration between cubital venous and uterine arterial serum, the half-lives being 8.0 and 7.9 hours, respectively. The initial concentrations were estimated to be 153 micrograms/ml and 160 micrograms/ml, respectively. The tissue peak concentrations were obtained at 30 minutes in the myometrium, portio vaginalis, oviduct and ovary, and at 1 hour in the endometrium and cervix uteri. These were 41, 51, 51, 39, 42 and 47 micrograms/g, respectively. The tissue concentrations after peak decreased in the same manner as the serum concentrations. Judging from its favorable transfer into the uterine tissues, CTRX was evaluated to be clinically useful in the treatment of obstetrical and gynecological infections.     

Analysis of the mechanism of cancer metastasis by using anticancer agents

For the analysis of the mechanism of cancer metastasis, effects of anticancer agents on the NK activity of spleen cells and on the artificial metastasis of B-16 melanoma cells were comparatively studied. The inhibitory effect of these anticancer agents on the growth of B-16 melanoma inoculated to foot pad of C57/BL6 mice was also examined. The growth of B-16 melanoma was inhibited by intravenous administration of 6 mg/kg of MMC, 18 mg/kg of KW-2083 and 5 mg/kg of CDDP, but not of 6 mg/kg of KW-2083. The NK activities in spleen cells of C57/BL6 mice administered with 6 mg/kg of MMC and 18 mg/kg of KW-2083 were decreased, but they were not decreased in mice administered with 6 mg/kg of KW 2083 and 5 mg/kg of CDDP. Significant increases in the number of artificial pulmonary and liver metastasis were observed in mice administered with 6 mg/kg of MMC and 18 mg/kg of KW-2083. It is suggested that the depression of NK activity induced by anticancer agents results in the promotion of metastatic disease.     

Intraretinal neovascularization in diabetic retinopathy

Nonperfused retinal areas were evaluated in 60 eyes (42 cases) with diabetic retinopathy through repeated fluorescein angiography. Revascularization occurred in the nonperfused area in 40 eyes, due to recanalization in 3 and to intraretinal neovascularization (IRNV) in 39 eyes. Recanalization and IRNV developed in the same fundus in 2 eyes. IRNVs occurred during the nonproliferative state in 11 eyes, concomitant with retinal neovascularization in 14 and after manifestation of proliferative changes in 14. Typically, IRNVs originated from and drained into a retinal venule, showed hairpin-loop at their tips and manifested minimum tendency of dye leakage. No retinal hemorrhage occurred from the IRNVs. Their unexpectedly high incidence and their timely association with retinal neovascularizations point to the importance of IRNVs in the diagnosis of preproliferative diabetic retinopathy.     

Experimental application of polyvinyl alcohol-silica for small artificial vessels

Polyvinyl alcohol-silica (PVA-SiO2) composite and heparinized PVA-SiO2 were examined in vitro and in vivo as materials to coat artificial vessels to be used for the replacement of small arteries. PVA-SiO2 was observed to prolong coagulation time and on heparinized PVA-SiO2 surfaces no blood coagulation was noticed after a period of two days using the Lee-White and plasma recalcification methods. After placing non-coated and coated surfaces in contact with blood components in vitro and in vivo, the degree of blood component adhesion was greater in non-coated woven Dacron than in PVA-SiO2 coated Dacron. The degree of adhesion was even less in heparinized PVA-SiO2 coated Dacron. Furthermore, artificial vessels made of these 3 types of materials were used to replace parts of the canine abdominal aorta and were removed one and a half years later. Patency rates were as follows: non-coated 2/7, PVA-SiO2-coated 4/7, heparinized PVA-SiO2-coated 8/12. The inner surfaces of these prostheses were observed with light microscopy and scanning electron microscopy. Intima formation was thinner on the PVA-SiO2 composite surfaces than on the control surfaces. Heparin acted as a local anticoagulant and PVA-SiO2 limited intima formation. This report showed that PVA-SiO2 composite coated surfaces can be effective for small artery replacement due to good tissue affinity and anticoagulability.