Postsurgical observations of mean hemispheric cerebral blood flow with patients receiving high-flow EC-IC bypass using a radial artery graft (preliminary report, one-year observation of 10 hemispheres)

BACKGROUND

When we encounter an inaccessible internal carotid artery lesion, we sacrifice the inaccessible internal carotid artery and, at the same time, establish a high-flow extracranial-to-intracranial arterial bypass (EC-IC bypass). Questions and concerns remain, however, about the dynamics of the patient's cerebral blood flow postoperatively.

METHOD

Ten hemispheres from 9 patients had received radial artery grafting as an EC-IC bypass with the simultaneous obstruction of the internal carotid artery. Their mean hemispheric cerebral blood flow (mCBF) was measured longitudinally during 1 year after surgery by single photon emission computed tomography (SPECT) and a 133Xenon-inhalation method.

RESULTS

The serial mCBF values of the five hemispheres with giant aneurysm or paracavernous meningioma were attenuated during the postoperative 3-month period and then returned to the normal range. In only one case did the postoperative reduction of mCBF fail to return to normal; in addition there was a memory disturbance that had developed and progressed. Five hemispheres with the ICA stenosis did not present reduction in mCBF. In three out of five hemispheres, transient elevation of mCBF at 1 month after surgery was observed.

Distribution of lamprey adrenocorticotropin and melanotropins in the pituitary of the adult sea lamprey, Petromyzon marinus

Three peptides containing the melanotropin (MSH)-core sequence, YXMXHFRWG, have been isolated recently from the pituitary glands of adult sea lampreys (Petromyzon marinus) and were tentatively assigned as lamprey adrenocorticotropin (ACTH), MSH-A, and MSH-B, respectively. Both MSHs differed significantly from gnathostome MSHs and cannot be assigned as alpha-MSH, beta-MSH, or gamma-MSH. The aim of the present study was to localize these peptides in the lamprey pituitary using antisera generated against synthetic lamprey ACTH1-16, MSH-A, and MSH-B. ACTH-like immunoreactivity was found in most cells of the rostal pars distalis (RPD) and in a few scattered cells of the proximal pars distalis (PPD). MSH-A-like immunoreactivity was found in most cells of the RPD, a few scattered cells of the PPD, and almost all cells of the pars intermedia (PI). MSH-B-like immunoreactivity was found only in the PI, where almost all cells were stained. Thus, the topographic distributions of ACTH and MSHs in the lamprey pituitary were similar to those in gnathostome vertebrates.

Proximal balloon occlusion for dissecting vertebral aneurysms accompanied by subarachnoid hemorrhage

Five patients with spontaneous dissecting vertebral aneurysms presenting with subarachnoid hemorrhage were treated with endovascular proximal balloon occlusion after a successful balloon Matas' test. Occlusion was performed in the extracranial portion of the vertebral artery after the potentially dangerous period of cerebral vasospasm. Two patients rebled preoperatively during the waiting period. Although angiograms demonstrated residual aneurysmal dilatation for four of the five patients, postoperative hemorrhages or progression of the dissection were not observed during the 19- to 48-month follow-up period. Only one patient experienced transient postoperative ischemic complication. Although the timing of the procedure and the site of occlusion remain controversial, proximal balloon occlusion of the vertebral artery appears to be a safe and effective therapy for patients with dissecting vertebral aneurysms presenting with subarachnoid hemorrhages. This method provides an important, less invasive alternative for this condition.

[Immunohistochemical studies on pathogenetic features of diffuse fasciitis]

Three cases of diffuse fasciitis were reported: case 1, a 24-year-old female, case 2, an 18-year-old male and case 3, a 61-year-old male. Their prominent features were reduced extensibility of the muscle and/or fascia. Skin was taut and bound underneath in cases 1 and 3, and focal edema was noted in the left forearm of case 2. Firmness of the muscle and/or fascia was dominantly seen in four extremities in case 1, proximal limbs in case 2 and in the trunk and proximal limbs in case 3. Muscle weakness was not seen in case 1, slight in the limbs of case 2 and moderate in the proximal limbs of case 3. Transient eosinophilia was observed in case 1. IgG was elevated in all 3 cases and IgM in cases 1 and 3. Antinuclear antibody was positive in case 1 and 2, and anti-ENA antibody in case 3. Remarkable thickening of the fascia and perivascular mononuclear cell infiltration in the fascia were main pathological features in all three cases. Inflammatory alteration of the muscle was modest and limited to the perifascicular and epimysial sites underneath the fascia. In these 3 cases, a diagnosis of Shulman syndrome or diffuse fasciitis with eosinophilia was made, although eosinophils were scarce in the fascia or muscle tissue. All 3 cases well responded to the oral prednisolone. Mononuclear cells clustered mainly in the perivascular sites, comprising mostly T cells, helper T cells, and partly B cells. These findings suggest that helper T cell mediated immune mechanism may play a pathogenetic role in this disease.(ABSTRACT TRUNCATED AT 250 WORDS)

[Clinical study of radiation pneumonitis over 10 years]

We studied clinical aspects of radiation pneumonitis from 1983 to 1992. Fifty seven patients admitted to our hospital because of lung cancer were treated with radiotherapy, and radiation pneumonitis developed in 20 (35.1%). The incidence of radiation pneumonitis was closely related to male sex, chronic obstructive lung disease, and chemotherapy. Pneumonitis was not related to age, or to the area or amount of radiation. Eighteen cases (90%) of pneumonitis occurred during or within one month after radiotherapy. In all but five cases (25%), pneumonitis was limited to the area of radiation. Treatment was mainly with steroids. In 4 cases (20%), pneumonitis recurred when steroid therapy was reduced, and five patients (10%) died.

Surgical treatment of childhood moyamoya disease--comparison of reconstructive surgery centered on the frontal region and the parietal region

Indirect revascularization procedures centered on the parietal region, such as encephalo-myo-arterio-synangiosis (parietal synangiosis) and direct procedures centered on the frontal region using both the anterior and the posterior branches of the superficial temporal artery (STA), such as STA to middle cerebral artery anastomosis combined with encephalo-duro-arterio-myo-synangiosis (frontal anastomosis) were compared in childhood moyamoya disease patients. The parietal synangiosis group consisted of 10 sides in five patients, and the frontal anastomosis group consisted of 30 sides in 15 patients. The development of postoperative collateral circulation was assessed by external carotid angiography, the neurological outcome was monitored for 2 years after surgery, and the intelligence quotient (IQ) was measured at least 6 months after surgery. Frontal anastomosis achieved superior results compared to the parietal synangiosis assessed by development of collateral circulation, in particular to the orbitofrontal artery, the prefrontal artery, and the precentral artery (p < 0.01), and reduction in the incidence of ischemic attacks, such as transient ischemic attacks (p < 0.05). The mean IQ in the frontal anastomosis group was higher than that in the parietal synangiosis group. Vascular reconstruction centered on the frontal region utilizing both the anterior and posterior branches of the STA is more efficacious than only synangiosis centered on the parietal region.

Induction of hepatic drug-metabolizing enzymes by chlornitrofen (CNP) and CNP-amino in rats and mice

The induction of hepatic drug-metabolizing enzymes by chlornitrofen (CNP) and CNP-amino was studied in the liver of male rats and mice. CNP-amino increased the activities of 7-pentoxyresorufin O-depentylase (PROD) and 7-benzyloxyresorufin O-debenzylase (BROD) as CYP2B1-dependent monooxygenase 3.6- and 4.1-fold in rats. On the contrary, these enzyme activities in mice were induced by CNP rather than by CNP-amino. Furthermore, immunoblotting showed that the protein levels of CYP2B subfamily cytochrome P450 (P450) in liver microsomes of rats and mice were increased by CNP or CNP-amino. Phase II drug-metabolizing enzymes, UDP-glucuronyltransferase (UGT) and glutathione S-transferase (GST) levels in mice were also significantly increased from 1.4 to 2.5-fold by CNP or CNP-amino. However, neither CNP nor CNP-amino affected UGT and GST in rats. These results suggest that CNP and or CNP-amino induce the P450 isoforms of CYP2B subfamily in the rat and mouse liver, and that the inducibility of drug-metabolizing enzyme by the compounds is different between rats and mice.

pH-dependent inactivation and reactivation of recombinant sheep angiotensinogen

Purified recombinant sheep angiotensinogen (rsAngn) lost 74% of the reactivity with human renin during storage at pH 8.0 and 4 degrees C. The inactivated rsAngn was reactivated by incubation at acidic pHs. This indicates that pH-dependent inactivation and reactivation occur in rsAngn.

Blood flow velocity in the common carotid artery in humans during graded exercise on a treadmill

Cerebral blood volume flow and flow velocity have been reported to increase during dynamic exercise, but whether the two increase in parallel and whether both increases occur as functions of exercise intensity remain unsettled. In this study, blood flow velocity in the common carotid artery was measured using the Doppler ultrasound method in eight healthy male students during graded treadmill exercise. The exercise consisted of stepwise progressive increases and decreases in exercise intensity. The peak intensity corresponded to approximately 85% of maximal oxygen consumption. During this exercise, the heart rate (fc), mean blood pressure (BP) in the brachial artery and mean blood flow velocity (vcc) in the common carotid artery increased as functions of exercise intensity. At the peak exercise intensity, fc, BP and vcc increased by 134.5%, 20.5% and 51.8% over the control levels before exercise (P < 0.01), respectively. The resistance index (RI) and pulsatility index (PI) were determined from the velocity profile and were expected to reflect the distal cerebral blood flow resistance. The RI and PI increased during the graded exercise, but tended to decrease at the highest levels of exercise intensity. As vcc increased with increases in exercise intensity it would be expected that cerebral blood flow would also increase at these higher intensities. It is also suggested that blood flow velocity in the cerebral artery does not proportionately reflect the cerebral blood flow during dynamic exercise, since the cerebral blood flow resistance changes.

Initiating activity of quinones in the two-stage transformation of BALB/3T3 cells

2-tert-Butyl-1,4-benzoquinone (BQ), a metabolite of the rodent carcinogen 3-tert-butyl-4-hydroxyanisole (3-BHA), has been shown previously to have initiating activity for cell transformation. In this paper, we examined the initiating activity of quinones in a two-stage transformation assay using BALB/3T3 cells. Cells were treated first with a quinone and then with the tumor promoter 12-O-tetra-decanoylphorbol-13-acetate (TPA). The quinones tested were 1,4-benzoquinone (pQ), phenyl-1,4-benzoquinone (PhQ), menadione and 2,5-di-tert-butyl-1,4-benzoquinone (DBQ) in addition to BQ. pQ is a metabolite of benzene and phenacetin, and PhQ is a metabolite of o-phenylphenol (OPP) and sodium o-phenylphenate (OPP-Na). All of the tested quinones induced transformation in the presence of TPA but not in its absence. The extent of transformation caused by quinones followed by TPA was weak but statistically significant. Thus these quinones were shown to act as initiators in the transformation of BALB/3T3 cells. This result suggests that BQ, pQ and PhQ may be involved in carcinogenesis by 3-BHA, benzene, phenacetin, OPP and OPP-Na in vivo. Menadione has been reported to cause cytotoxic effects and mutations through active oxygen generation from semiquinone radicals. DBQ has two bulky substitutes which interfere with covalent bonds with DNA. Menadione and DBQ exhibited initiating activity in the present study. This result suggests that active oxygens generated from semiquinone radicals may play a role in the initiation of cell transformation.

Hepatoprotective effect of SY-640, a novel acetamide derivative, on Propionibacterium acnes and lipopolysaccharide-induced liver injury in mice

The hepatoprotective effect of SY-640 on Propionibacterium acnes and lipopolysaccharide-induced liver injury in mice and its protective mechanism were examined. Oral administration of SY-640, 150 mg/kg once daily for 7 days, significantly inhibited Propionibacterium acnes and lipopolysaccharide-induced liver injury, but a single administration was without effect. Liver-infiltrating cells (T-lymphocytes and macrophages) play an important role in Propionibacterium and lipopolysaccharide-induced liver injury and express a higher level of leukocyte function-associated antigen-1. SY-640 inhibited the number of liver-infiltrating cells and attenuated the increased expression of leukocyte function-associated antigen-1 on these cells. Tumor necrosis factor-alpha mediated Propionibacterium acnes and lipopolysaccharide-induced liver injury, and SY-640 inhibited the elevation of the serum tumor necrosis factor-alpha concentration after injection of lipopolysaccharide in Propionibacterium acnes-primed mice. The putative effects of SY-640 are inhibitory effects on infiltration into the liver and on activation of T-lymphocytes and macrophages after Propionibacterium acnes-priming, and attenuation of expression of cell adhesion molecules such as leukocyte function-associated antigen-1. The immunological effect of SY-640 is likely to be closely related to the inhibition of Propionibacterium and lipopolysaccharide-induced liver injury.

Differences in features of calcium transients between the nucleus and the cytosol in cultured heart muscle cells: analyzed by confocal microscopy

We analyzed spatio-temporal characteristics of Ca2+ transients in the cytosol and the nucleus of cultured neonatal rat heart cells using confocal imaging with Indo-1 and Fluo-3. In resting heart muscle cells, nuclear [Ca2+] was maintained lower than the cytosolic level. The rise in nuclear [Ca2+], during either E-C coupling or propagation of the Ca2+ wave, began at the edge of the nucleus in the immediate vicinity of the rise in global or localized cytosolic [Ca2+], and spread inwardly. The rise in [Ca2+] was slower and smaller in the nucleus than in the cytosol. The decay in [Ca2+] was also slower in the nucleus than the cytosol, thereby reversing the initial [Ca2+] gradient between them. Caffeine markedly enhanced the rise in nuclear [Ca2+] while maintaining inward spreading. The heterogeneity of nuclear Ca2+ transients during cellular contractilities suggests that influx of Ca2+ from perinuclear stores into the nucleus plays a predominant role in the nuclear [Ca2+] rise. The results also indicated that spatio-temporal characteristics of Ca2+ transients are quite different between the nucleus and the cytosol, thereby suggesting that they are differentially regulated in the nucleus and the cytosol.

Pentobarbital protects against CA1 pyramidal cell death but not dysfunction of hippocampal cholinergic neurons following transient ischemia

Effects of pentobarbital on the release of acetylcholine (ACh), the area of CA1 pyramidal cell soma and the immunoreactivity of choline acetyltransferase (ChAT) in the hippocampus following ischemia were investigated. Five minute ischemia significantly decreased the KCl-, atropine-induced and basal release of ACh and the area of CA1 pyramidal cell soma in the hippocampus. Moreover, ChAT immunoreactivity, a marker of pre-synaptic terminal survival in the cholinergic neurons, was lowered 14 days after ischemia-recirculation. Although treatment with pentobarbital (50 mg/kg) 30 min before ischemia provided complete protection against hippocampal CA1 pyramidal cell death, pentobarbital failed to improve the decrements of ACh release and the low ChAT immunoreactivity over the test period. Our study thus showed discrepancies between pre-synaptic neurochemical estimation and post-synaptic morphological observation of the effect of pentobarbital on ischemic damage.

Immunohistochemical and neurochemical studies of hippocampal cholinergic neurones after ischaemia

We investigated alterations in cholinergic neurones in the gerbil hippocampus after ischaemia. The cholinergic function of acetylcholine (ACh) release fluctuated over the test period. Choline acetyltransferase (ChAT) immunoreactivity decreased slightly on day 1 and no ChAT immunoreactivity was observed on or after day 4 after ischaemia. Since ChAT immunoreactivity is a marker of cholinergic terminal survival, post-ischaemic cholinergic dysfunction on and after day 4 was accompanied by the destruction of terminals. However, dysfunction of the cholinergic system without destruction of the terminals is possible since mild ischaemia decreases ACh release in spite of retaining intact ChAT immunoreactivity. In the morphological study, delayed neuronal death in the stratum pyramidale was observed from day 4. The present study shows that presynaptic cholinergic dysfunction occurs in the early stage prior to pyramidal cell death.

Neuronal expression of FOS protein in the nucleus tractus solitarii and the dorsal motor nucleus of the vagus nerve after i.p. injection of ulcerogenic aspirin

Aspirin, a common analgesic-antipyretic and anti-inflammatory drug, often induces gastric ulcer, but its pathogenesis remains unsettled. The purpose of this study was to identify the CNS neurons that express FOS protein after i.p. injection of aspirin (100-300 mg/kg). This was done in the unanesthetized Wistar rats with careful physiological controls. Dose-dependently, many FOS-immunoreactive (FOS-ir) neurons were found in the medial part of the nucleus tractus solitarii (NTSm) and the dorsal motor nucleus of the vagus nerve (DMX) of the lower medulla, but none in the paraventricular nucleus of the hypothalamus (PVH). Distribution of FOS-ir neurons in the DMX corresponds with that of the visceromotor neurons involved in gastric secretion. This study suggests that the aspirin-induced gastric ulcer may not originate in the PVH but in the NTSm-DMX system.

Spinal cord morphology and pathology in ossification of the posterior longitudinal ligament

We analysed nine autopsy cases of ossification of the posterior longitudinal ligament (OPLL) to elucidate the relationship between morphology and pathology of the spinal cord. The cross-sectional shape of the spinal cord at the most severely affected segment was classified into two categories: boomerang (convex lateral surfaces and concave anterior surface) and triangular (angular lateral surfaces and flat anterior surface). In the cases with a boomerang shape, even when the compression was severe, major pathological changes were restricted to the grey matter and the white matter was relatively well preserved. No secondary descending degeneration of the lateral columns was seen, and ascending degeneration of the posterior column was restricted to the fasciculus cuneatus whose fibres were derived from the affected segments. In the cases with a triangular shape, pathological changes were more severe, both white matter and grey matter were involved, and only the anterior columns were free of pathological changes. There were severe pathological changes over more than one segment, and both descending degeneration of the lateral pyramidal tracts and ascending degeneration of the posterior column, including the fasciculus gracilis, were observed. The transverse area of the spinal cord was > 60% of normal in most of the cases with a boomerang shape, but it was reduced to < 60% of normal in more than one segment in the cases with a triangular shape. The compression ratio of the spinal cord (sagittal diameter/transverse diameter x 100%) was not related to pathological changes. In conclusion, a triangular-shaped spinal cord with transverse area of < 60% of normal in more than one segment appeared to be associated with severe and irreversible pathological changes in cases of OPLL.

[An autopsy case of intravascular malignant lymphomatosis with intracranial lymphomatous mass lesions]

A 50-year-old man was admitted to our hospital, because of weakness in his right leg. On admission, he had generalized hyperreflexia and positive Babinski signs bilaterally. After admission, weakness in his left leg and confusion developed. A cerebrospinal fluid examination revealed increases in cell counts and protein but was negative for malignant cells. Blood chemistry was normal except for elevated LDH. A bone marrow biopsy yielded lymphoma cells. Successive T2-weighted cranial MRI showed a progressively expanding high signal area in the right parieto-occipital lobe. His confusional state improved after chemotherapy; however, two months later another cranial CT showed multiple enhanced mass lesions. The patient died 20 months after the onset of illness. Postmortem examination revealed widespread intravascular aggregates of malignant lymphomatous cells in the cerebrum, lungs and kidney, as well as multiple infarcts without atherosclerosis in the cerebrum. These pathological findings are compatible with those of intravascular malignant lymphomatosis. In addition, extravascularly expanding tumor cells formed multiple nodular lesions in the cerebral hemisphere. An immunohistochemical study showed that the tumor cells were positive for B-cell marker L26. Intracranial lymphomatous mass lesion rarely occurs in cases of intravascular malignant lymphomatosis. In the present case, tumor cells were presumably restricted to intravascular spaces, occluded them and resulted in ischemic lesions in the cerebrum in the early phase, but they expanded extravascularly and developed mass lesions in the terminal stages. In conclusion, intravascular malignant lymphomatosis is considered to be phenotypes of malignant lymphoma. This is the first case of intravascular malignant lymphomatosis associated with intracranial lymphomatous mass lesions in Japan.

Interaction of tetrachloroethylene with rat hepatic microsomal P450-dependent monooxygenases

1. We have studied the effects of tetrachloroethylene (PCE) on the kinetics of the P450-dependent monooxygenases in rat liver microsomes. 2. 7-Pentoxyresorufin O-depentylase (PROD) and 7-benzyloxyresorufin O-debenzylase (BROD) activities in phenobarbital (PB)-treated rat liver microsomes were substantially inhibited by PCE. The inhibition profiles were non-competitive for both enzyme activities; Ki's from Eadie-Hofsee plots were 0.16 and 0.29 mM for PROD and BROD respectively. In contrast, the enzyme activities in untreated, beta-naphthoflavone (BNF)-, isoniazid (ISN)- and pregnenolone-16 alpha-carbonitrile (PCN)-induced microsomes were not affected by PCE. 3. 7-Ethoxycoumarin O-deethylase (ECOD) activity in PB-induced microsomes was competitively inhibited by PCE, with a Ki that was lower than those of other microsomes. 4. PCE inhibited 7-ethoxyresorufin O-deethylase (EROD) activities in some microsomes slightly. The Ki for PCE was the lowest in untreated, followed by ISN-treated microsomes. 5. No effect of PCE upon aniline 4-hydroxylase (AN4H) and testosterone 6 beta-hydroxylase (TS6BH) activities was evident in any microsomal preparation. 6. These results indicate that PCE inhibits PB-inducible, P450-dependent monooxygenases in vitro non-competitively or competitively, and that the P450 enzymes of the P4502B subfamily may contribute to PCE toxicity.

Gastrointestinal dysfunction in Parkinson's disease detected by electrogastroenterography

Electrogastroenterography (EGEG) is a method to record electrical activities of the stomach and the intestine using skin electrodes. We investigated whether this method could be used to detect gastrointestinal dysfunction in patients with idiopathic Parkinson's disease. EGEG recordings were done with ten patients with idiopathic Parkinson's disease and ten control subjects before and after a meal. The patients showed changes in EGEG that were markedly similar to those of acute stage of vagotomized patients reported previously. Patients' increase rate in amplitude of gastric activity after the meal (median: 1.19) was significantly (P < 0.05, Mann-Whitney test) smaller than that of the controls (median: 2.84), and normal temporal frequency decrease of gastric activity after the meal was not seen in the patient group. These results suggest vagal nerve dysfunction of patients with Parkinson's disease, though other possibilities could not be denied. EGEG may be useful to assess patients' gastrointestinal dysfunction though we need further study to elucidate the relation between pathophysiology of their symptoms and EGEG findings.

Experimental dental caries on gnotobiotic inbred mice

The purpose of this study in mono-infected gnotobiotic BALB/cA and C3H/HeN mice was to evaluate the cariogenicity of Enterococcus faecalis. The caries incidence and mean caries score in the BALB/cA mice were significantly higher than those in the C3H/HeN. In both of the mouse strains, the mean number of E. faecalis isolated from the cecum content was almost the same, however, the mean number of E. faecalis from the maxilla of BALB/cA was significantly higher than that of C3H/HeN. These results indicate that C3H/HeN has some factors that prevent E. faecalis from attaching to the tooth surfaces.

Myocardial blood flow: comparison of oxygen-15-water bolus injection, slow infusion and oxygen-15-carbon dioxide slow inhalation

This study investigates the most appropriate protocol for measuring regional myocardial blood flow (MBF) using 15O-water in clinical applications.

METHODS

Regional MBF, perfusable tissue fraction (PTF) and arterial blood volume (Va) were measured using 15O-water and dynamic PET on five healthy volunteers based on previously published models. Calculated values were compared for the following three tracer administration protocols: 15O-water bolus injection, 15O-water slow (2 min) infusion and 15O-carbon dioxide slow (2 min) inhalation. For the two slow administration protocols, the three parameters MBF, PTF and Va were computed by fitting the model equations to the myocardial regional time-activity curve. For the bolus injection of 15O-water, only two parameters, MBF and PTF, were fitted by using a fixed Va value obtained by a carbon dioxide blood volume scan.

RESULTS

All protocols provided consistent MBF values, and the calculated values were homogeneous throughout the whole myocardial segments for all subjects. PTF values were also homogeneous and consistent in the anterior and lateral wall regions, but were significantly greater in the septum (approximately 20%) when the slow 15O-carbon dioxide inhalation protocol was used. MBF and PTF values obtained from the bolus injection protocol showed the smallest intersubject and interregional variations. The simulation study also showed that the magnitude of error was smallest when the bolus injection protocol was employed.

CONCLUSION

The data suggest that the 15O-water bolus injection protocol together with the two-parameter fitting procedure provides the most accurate results for MBF and PTF. However, it requires arterial cannulation and a separate carbon monoxide scan. For clinical studies, however, the 15O-water infusion protocol would be a good alternative, providing MBF and PTF results with an acceptable degree of accuracy and without the need for arterial cannulation.

[Complete remission in acute myeloblastic leukemia (M0) after treatment with rhG-CSF]

A 57-year-old man was admitted because of fever and night sweat. The bone marrow was hypercellular with 86.4% blast cells. The diagnosis of AML (M0) was made, because the blast cells were negative for peroxidase stain and had CD13 and no lymphoid antigens in marker analysis. The patient was treated with BH-AC.TMP, BH-AC.MVP and low dose Ara-C without any hematological improvement, and even additional treatment with medium dose Ara-C resulted in 66.4% blast cells in the bone marrow. Subsequent administration of rhG-CSF (150 micrograms/day) by continuous intravenous infusion resulted in the decrease of the blast cells in the bone marrow to a level that was evaluated as complete remission. He remains in complete hematological remission at present. As shown in this case, rhG-CSF might be an effective agent for the treatment of AML, even if the mechanism of its effectiveness is unclear at present. Further clinical studies should will supply useful information to analyze the pathophysiology of AML.

[The relationship among hematocrit, platelet aggregation and the time of onset in patients with acute stage-cerebral infarction]

We evaluated time relation among hematocrit (Ht), platelet aggregation (PA) and the onset of acute stage-cerebral infarction in 221 patients. Lacunar infarctions were likely to occur in the evening or at midnight. The elevated Ht value was frequently found in patients with infarctions occurring at midnight, suggesting that the elevation of blood viscosity has an intimate etiology to the onset. The decrease of PA was often found in those who suffered from their stroke while awake in the morning or at midnight, and frequently had been associated with elevated Ht in the latter patients. Decrease of PA is often reported during acute stage-cerebral infarction. Our results indicate that increased platelet aggregation may play an important role in developing cerebral infarction, especially in those who had onset of illness in the morning.

Characterization of neo red cells (NRCs), their function and safety in vivo tests

The Neo Red Cells (NRCs), a new type of artificial oxygen carriers have been developed and investigated for oxygen transport capacity, hemodynamics and safety in experimental animals. Stroma free hemoglobin (Hb) prepared from outdated human red blood cells was encapsulated together with inositol hexaphosphate (as an allosteric effector), coenzyme and substrates for reducing metHb back to Hb in liposomes under an aseptic condition. The NRCs were subsequently coated with polyethylene glycol bound to phosphatidylethanolamine as surface modifier to prevent aggregation of NRCs in plasma. The metHb formation was reduced from 1%/hr to 0.37%/hr by the addition of metHb reduction system. The blood pressure increased transiently during injection, and then immediately returned to pre-injection levels. The efficiency of the NRCs in tissue oxygenation and recovery from anemia was studied in rabbits which had been made severely anemic by drawing 85% of their blood and replacing it with NRCs. All of the animals infused with NRCs recovered to pre-anemic conditions within 6-8 hr and survived until they were sacrificed, 6 months after the exchange transfusion. Our observations suggest that the NRCs are pathogen free, efficient oxygen carriers without causing serious adverse reactions, with controllable metHb formation in vivo and during storage.