Potential etiologic role of PAF in two major septic complications; disseminated intravascular coagulation and multiple organ failure

A possible role of platelet-activating factor (PAF) in the occurrence of the two septic complications, i.e., disseminated intravascular coagulation (DIC) and multiple organ failure (MOF) was investigated, employing a rabbit model and a novel PAF antagonist E5880. By an instillation of fecal suspension into the common bile duct of the rabbit, manifestations of DIC and MOF were observed with high reproducibility by 9 hours after the septic insult. E5880 was intravenously administered to 12 rabbits for 1 hour after the septic insult at dose of 1 mg/kg (n = 6) or 3mg/kg (n = 6). All the rabbits were subjected to observation of vital signs and serial determination of laboratory tests for 9 hours and then lung, liver and kidney were removed for histological examination. Blood endotoxin level increased significantly by 9 hours after the septic insult. Although administration of E5880 did not affect the endotoxemia, the antagonist attenuated in a dose related manner laboratory manifestation of DIC such as thrombocytopenia and prolonged prothrombin time as well as that of MOF such as increase in serum bilirubin and creatinine level. The beneficial effect of E5880 on MOF was also confirmed by the histological evaluation. These observations indicated that PAF is deeply involved in the occurrence of DIC and MOF due to sepsis and E5880 may be one of the modalities to treat or prevent these two major septic complications.

A new method of purification and sensitive bioassay of platelet-activating factor (PAF) in human whole blood

There is no satisfactory assay procedure of PAF in human whole blood in terms of sensitivity, reproducibility and simplicity. This is due to coexisting lipids from plasma and cellular membranes which inhibit measurement of PAF in various assay procedures, including bioassay. In the present study, an attempt was made to eliminate these interfering lipid inhibitors from blood samples. Lipids in human whole blood were extracted according to the method of Bligh & Dyer and the organic layer was dried under a stream of nitrogen. Then, the dried organic layer was dissolved in diethyl-ether and the solution was kept at -20 degrees C which was then centrifuged. The resulting supernatant was then applied to an anion-exchange column and the PAF fraction was obtained by step-wise gradient elution. The fraction was further purified by normal phase HPLC. Then PAF in the final sample was determined by sensitive bioassay using rabbit platelets containing fibrinogen and epinephrine. The recovery rate of PAF throughout this procedure was constant and satisfactory (37.4 +/- 9.7%), which was confirmed using [3H]-PAF. The lower limit of the present assay was estimated to be 5pg in 1 ml of blood and it was sensitive enough to detect PAF in blood samples from healthy volunteers and patients with sepsis or liver cirrhosis. Furthermore, attempts were made to compare the sensitivity and the recovery of our method with these of a commercially available radioimmunoassay (RIA) kit for PAF. However, it was not possible to detect any amount of authentic PAF added to whole blood.

Pharmacokinetic study of loprinone hydrochloride, a new cardiotonic agent, in beagle dogs

Pharmacokinetic parameters and bioavailability of a new cardiotonic agent, loprinone hydrochloride, in beagle dogs were determined by measuring plasma levels of loprinone after intravenous bolus and oral administration. The plasma half-life after intravenous administration of loprinone varied among individuals over the range 2.65-15.40 h. The bioavailability after oral administration of loprinone as a solution was 37.1%. Effects of enterohepatic circulation on the time-course of plasma levels after intravenous administration of the drug were also studied in bile-duct-cannulated beagle dogs. The amounts of loprinone and its glucuronide excreted in bile during 8 h after administration were 25.4 and 8.6% of the dose, respectively, indicating the possibility of enterohepatic circulation. The plasma half-life in bile-duct-cannulated beagle dogs was 1.98 h. These results indicate that the variation in the half-life in beagle dogs resulted from enterohepatic circulation and that the true half-life is about 2 h. The relative bioavailability after oral administration of the drug as a powder in a capsule compared with a solution was 95.7%. In addition, the amounts of loprinone and its glucuronide excreted in bile, and the AUC of plasma level after infusion for 30 min into the portal vein in bile-duct-cannulated beagle dogs were similar to those after bolus intravenous administration. These results show that the low bioavailability reflects incomplete absorption.

Epstein-Barr virus in gastric carcinoma

Epstein-Barr virus (EBV) is known to be related to lymphoid tumors and some types of epithelial tumors, including lymphoepithelioma-like gastric carcinoma with marked lymphocytic stroma. In this study, prevalence of EBV involvement in gastric cancer, and characteristics of tumors with such involvement, were investigated by EBV-encoded RNA 1 in situ hybridization applied to paraffin sections, including the tumor and adjacent gastric tissue, from 999 gastric carcinomas observed in 970 consecutive cases from a large Japanese hospital. EBV involvement occurred in 6.9 percent of lesions, a significantly lower proportion than has been observed in a North American series. Involvement was significantly more frequent among males, in tumors in the upper part of the stomach, and in adenocarcinomas of the moderately differentiated tubular and poorly differentiated solid or medullary types. Almost all carcinomas with marked lymphoid stroma were EBV-positive. Positive lesions were characterized by the presence of uniform hybridized signals in almost all carcinoma cells and by their absence from adjacent non-neoplastic tissue.

Epstein-Barr virus in adult T-cell leukemia/lymphoma

Adult T-cell leukemia/lymphoma (ATLL) is a well-known human T-cell lymphotropic virus type-1-related disease. We studied Epstein-Barr virus (EBV) in the tumor cells of ATLL, to investigate the etiological significance of double infection with these viruses. We used polymerase chain reaction and EBV-encoded small RNA-1 in situ hybridization to investigate the presence of EBV and immunohistochemistry to detect EBV-related oncoproteins, such as EBV-determined nuclear antigen-2 and latent membrane protein. Polymerase chain reaction performed on DNA of frozen specimens from 96 cases of ATLL revealed that the tumor tissue from 21 cases contained EBV DNA. EBV-encoded small RNA-1 in situ hybridization performed on the paraffin sections of the polymerase chain reaction-positive cases indicated EBV in the nuclei of ATLL tumor cells in 16 cases, nine of which were in the pleomorphic nuclei. Latent membrane protein was also detected in the cytoplasm of ATLL tumor cells in 15 cases, and EBV nuclear antigen-2 was observed in the nuclei of ATLL tumor cells in 11 cases. We conclude that EBV was present within tumor cells in about 17% of cases with ATLL and expressed EBV oncoprotein in the tumor cells. It is hypothesized that EBV and human T-cell lymphotropic virus-1 may infect the same T cells in early life and may play a role in the oncogenesis of ATLL.

Epstein-Barr virus related gastric cancer in Japan: a molecular patho-epidemiological study

Epstein-Barr virus (EBV) involvement in gastric carcinoma has been demonstrated by the presence of EBV genomes and EBV-encoded small RNA (EBER) in the carcinoma cells, monoclonal proliferation of EBV-infected carcinoma cells and elevated antibody titers. The present study was conducted to investigate the prevalence of EBV involvement among gastric carcinomas observed in nine Japanese cities with varying gastric cancer rates. In situ hybridization of EBER-1 was applied to paraffin sections from 1848 carcinomas observed in 1795 cases and EBV involvement was detected based on uniform hybridization in carcinoma cells. Epstein-Barr virus was detected in 6.6% of lesions and 6.7% of cases. The rate of EBV involvement did not vary significantly for each city and there was no correlation with underlying gastric cancer mortality rates. Thus, geographic variation of gastric cancer rates within Japan cannot be explained in terms of EBV involvement. Epstein-Barr virus-related gastric carcinoma is one of the most common EBV-related tumors in Japan. The involvement of EBV was significantly more frequent among males than among females, mainly for cancers occurring in the upper and middle part of the stomach, and exhibited more variation by cell type among males. These observations suggest that other factors yet to be discovered may modulate the causal role of EBV in gastric carcinogenesis.

Purification and characterization of endogenous protein activator of human platelet proteasome

An endogenous activator of 20S proteasome was purified from human platelets and its effect on three peptidase activities of proteasome was studied. This activator had a molecular weight of 170 kDa, and was composed of 32 kDa polypeptides as determined by SDS-PAGE. It was highly labile upon heat treatment (56 degrees C, 20 s) and proteinase (pronase CB) digestion. Suc-LLVY-MCA degrading activity of the platelet proteasome showed positive cooperativity between two or more catalytic sites because the coefficient was 1.54 when analyzed by use of the Hill plot. The endogenous activator increased Vmax and caused a loss of cooperativity. The plot of reaction velocity as a function of activator concentration yielded a saturation curve, implying the binding of the activator to proteasome. Boc-LTR-MCA degrading activity followed Michaelis-Menten kinetics. The activator enhanced the activity by increasing Vmax and decreasing Km. In contrast, CBz-LLE-2NA degrading activity could not be analyzed according to any kinetic scheme reported so far. The activator stimulated this activity at lower substrate concentrations (below 200 microM), while it inhibited the activity at higher substrate concentrations (400-800 microM). It is concluded from these findings that the endogenous protein activator may regulate the intracellular proteasome activity by functioning as a positive allosteric effector.

Calyculin A inhibits the exposure of fibrinogen receptor in thrombin-stimulated platelets

Calyculin A (CLA) and okadaic acid (OA), specific and potent inhibitors of protein phosphatase 1/2A, inhibit platelet aggregation. However, their inhibitory mechanisms remain unknown. We investigated the effects of CLA on the exposure of fibrinogen receptor in thrombin-stimulated platelets, using flow cytometry with a monoclonal antibody against the fibrinogen receptor of activated glycoprotein(Gp)IIb/IIIa complex (PAC-1). CLA inhibited the exposure of fibrinogen receptor in a dose related manner when added either before or 3 min after thrombin stimulation. In contrast, CLA had no significant effect when the expression of GpIIb/IIIa complex was examined in resting platelets, using a monoclonal antibody recognizing non-activated GpIIb/IIIa complex (NNKY1-32). These results suggest that protein phosphatase 1/2A may be directly involved in the exposure of platelet fibrinogen receptor.

Ischemic tolerance due to the induction of HSP70 in a rat ischemic recirculation model

Various studies have demonstrated an increase in heat shock protein 70 (HSP70) synthesis in the brain following transiently induced ischemia, suggesting a protective role for HSP70 against ischemic insult. In this study, we determined the time course of HSP70 mRNA and protein induction in rat hippocampus following ischemia using Pulsinelli's four-vessel occlusion model, and suggested a protective role for HSP70 induction in limiting ischemic damage to neurons and delayed neuronal death. In Northern blotting analysis using human HSP70 DNA as a probe, the accumulation of HSP70 mRNA after 5 min ischemia became evident at 4 h, and continued until 16 h, while after 30 min ischemia, HSP70 mRNA appeared at 2 h, and continued above control level until 24 h after treatment. In immunoblot analysis using anti-HSP70 antibody, induction of HSP70 protein appeared 24 h and reached a maximum 48 h after 5 min ischemia. In immunohistochemical analysis using anti-HSP70 antibody, staining was not detected in CA1 neurons until 16 h after 5 min ischemia, but staining in CA1 gradually increased 1 day after ischemia and reached a maximum level 2 days after ischemia. Similar time profiles in the staining pattern of HSP70 protein were observed in CA3 and CA4 neuronal cells following 30 min ischemia. When rats pretreated with 5 min ischemia (non-lethal for CA1 pyramidal neurons) were exposed to a 30 min, lethal period of ischemia, 2 days after pretreatment, considerable staining of HSP70 was observed. Pretreated rats had much less neuronal damage in the CA1 sector than did rats subjected to lethal, 30 min ischemia alone.(ABSTRACT TRUNCATED AT 250 WORDS)

Immunohistochemical detection of Pneumocystis carinii in transbronchial lung biopsy specimens: antigen difference between human and rat Pneumocystis carinii

Transbronchial lung biopsy specimens, from three patients with non-AIDS-related Pneumocystis carinii pneumonia (PCP) and rat lung tissue in which PCP was induced by the administration of dexamethasone, were studied to determine the diagnostic usefulness of an immunohistochemical method using commercially available anti-Pneumocystis monoclonal antibody, 3F6, on formalin-fixed, paraffin-embedded tissue. PC was consistently stained a bright red color and unambiguously identified in all three human lung specimens, but not stained in lung tissues at autopsy from patients with various fungal pneumonias. In contrast, PC was weakly stained in PCP-induced rat lungs. The present study indicates human PC and rat PC to be antigenically different in terms of the existence of the 82 kilo-dalton (kD) antigen against which 3F6 is directed.

The Tokyo Metropolitan Home Vision Screening Program for amblyopia in 3-year-old children

In August 1989, the Tokyo Metropolitan Government officially began a vision screening program for children aged 3 years 1 month. A 1988 pilot study of 1,303 children this age disclosed five cases (0.38%) of amblyopia. The home vision test, which uses picture cards of familiar figures, proved to be an efficient and inexpensive method of screening when incorporated into the existing health-check program for 3-year-old children. In the initial eight months of the program, 21,906 children were screened. Of these, 419 children (1.9%) were referred to an ophthalmologist for follow-up, and amblyopia was detected in 41 children (0.19%).

A novel CoA-independent transacetylase produces the ethanolamine plasmalogen and acyl analogs of platelet-activating factor (PAF) with PAF as the acetate donor in HL-60 cells

In this study, we demonstrate the presence of a unique membrane-associated transacetylase that transfers the acetate group from platelet-activating factor (PAF) to lysoplasmalogen (in the presence of EDTA and sodium acetate) with the formation of 1-alk-1-enyl-2-acetyl-sn-glycero-3-phosphoethanolamine (alk-1-enylacetyl-GPE). The identity of alk-1-enylacetyl-GPE was confirmed by acid hydrolysis, phospholipases A2 or C treatment and derivatization by fluorodinitrobenzene. The transacetylase has no requirement for Ca2+, Mg2+, or CoA and a broad pH optimum (7.0-8.0) with Km values of 12.0 microM for PAF and 106.4 microM for lysoplasmalogens. The enzyme activity from the isolated membrane fraction is not changed when whole cells are supplemented with 20:4, induced to differentiate into granulocytes, or treated with ionophore A23187. Radyllyso-sn-glycero-3-phosphocholine (GPC), radyllyso-GPE, acyllyso-sn-glycero-3-phosphoserine (GPS), acyllyso-sn-glycero-3-phosphoinositol (GPI), alkyllyso-sn-glycero-3-phosphate (GP), acyllyso-GP, or cis-9-octadecen-1-ol can also serve as acetate acceptors, whereas alkylglycerol, acylglycerol, or cholesterol are inactive. Differences in substrate acceptor specificity, sensitivity toward phenylmethylsulfonyl fluoride, and response to temperature suggest that the CoA-independent transacetylase and the CoA-independent transacylase that transfers long-chain acyl moieties are two separate enzymes. With intact differentiated HL-60 cells, [3H]acetate from [3H]PAF can be incorporated into alk-1-enylacetyl-GPE in the presence of ionophore A23187, but not in its absence. Moreover, phospholipase A2 inhibitors (p-bromophenacyl bromide and mepacrine) block the transacetylation process in whole cell system. These results indicate the production of alk-1-enyllyso-GPE is a rate-limiting factor for the subsequent transacetylation step during cell activation. We conclude that the transacetylase may participate in the biosynthesis of ethanolamine plasmalogen and acyl analogs of PAF, in vivo, fine-tuning of PAF biological responses, and cross-talk between de novo and remodeling pathways of PAF biosynthesis.

Alpha-elastin coacervate as a protein liquid membrane: effect of pH on transmembrane potential responses

A protein liquid membrane composed of coacervated alpha-elastin, a chemical fragmentation product of the biological elastic fiber protein, functioned as an amphoteric liquid ion-exchange membrane. Ionic permselectivities of the alpha-elastin coacervate membrane to a series of metal chlorides were investigated for the concentration-cell systems by the ordinary electrochemical measurements. Effects of pH on the transmembrane potential responses for NaCl, CaCl2, and MgCl2 systems were examined. Only in the Ca(2+)-containing system did potential responses stay at constant levels against the pH changes, whereas in the other systems, increasing pH caused potential changes, indicating an improvement of cationic permselectivity across the alpha-elastin coacervate membrane. It was suggested that the characteristic Ca2+ transport mechanisms across the alpha-elastin coacervate membrane are related in some way to the polypeptide backbone interactions specific and selective to Ca2+ ions.

[Intensive induction chemotherapy of adult acute myelogenous leukemia by continuing daunorubicin, behenoyl-cytosine arabinoside, 6-mercaptopurine and prednisolone until marrow aplasia]

Intensive induction chemotherapy was applied to 25 patients with acute myelogenous leukemia by continuing drugs (daunorubicin, behenoyl-cytosine arabinoside, 6-mercaptopurine and prednisolone) until the achievement of severe bone marrow aplasia (leukemic cells less than 1,000/microliters). Complete remission (CR) was achieved in 18 (72%). Numbers of partial remission and an early death were 5 (20%) and 2 (8%), respectively. Although median nadirs of white blood cells (WBC) and platelet counts (Pl) (205/microliters and 8,200/microliters, respectively) were remarkably low, recovery of WBC (over 1,000/microliters) and Pl (over 50,000/microliters) were achieved in 23.8 and 24.5 days, after an initiation of the chemotherapy. Sepsis was a most frequently observed complication during induction stage and a duration of fever was 2-48 days (median 15). Median duration of CR was 22.9 months. Unexpectedly, 11 of 17 CR (except one with bone marrow transplanted) relapsed after 4.2-41.4 months (median; 9.4), but 6 (35.3%) still remain in first CR for 30.5-72.9 months (median; 51.4). A long-term survival might be obtained by intensifying induction chemotherapy in about one fourth of patients, but the intensification or application of non-cross resistant anti-leukemic agents in post-remission therapy may be required to avoid relapses even if induction is intensified.

Acute megakaryoblastic leukemia: establishment of a new cell line (MKPL-1) in vitro and in vivo

A megakaryoblastic cell line (MKPL-1) was newly established from the bone marrow of an adult patient with acute megakaryoblastic leukemia. This cell line grew in single cell suspension with a doubling time of 30 h and consisted of large primitive blasts with persistent development of giant cells carrying multilobed nuclei. MKPL-1 cells were positive for platelet GPIIb/IIIa (CD41) and GPIIIa (CD61), and expressed OKM5 (CD36), MY7 (CD13), and MY9 (CD33) antigens in the absence of erythroid and lymphoid markers. The cytochemical and morphologic characteristics of MKPL-1 were also consistent with those of megakaryoblasts. The cells did not, however, express ultrastructural platelet peroxidase which is considered to be another marker of the megakaryocytic lineage. Cytogenetic analysis of MKPL-1 revealed a model chromosome number of 92 with abnormal chromosomes including those found in the patient's bone marrow cells. Furthermore, MKPL-1 cells were serially transplanted into nude mice for nine passages with production of lethal tumors and leukemic manifestation. Thus, our megakaryoblastic cell line which can be maintained both in vitro and in vivo would be useful for further studies of the biology of megakaryopoiesis and megakaryoblastic leukemia.

Human pulmonary hypoplasia. Statistical, morphological, morphometric, and biochemical study

Human pulmonary hypoplasia was studied statistically and pathologically in a large series of autopsy cases. Multiple logistic regression analysis indicated five independent risk factors from 10 statistically significant factors for pulmonary hypoplasia: (1) hydrops fetalis; (2) renal anomalies; (3) hernia, including diaphragmatic hernia and omphalocele; (4) skeletal anomalies; and (5) abnormalities of amniotic fluid, such as oligohydramnios and polyhydramnios. The characteristics of pulmonary hypoplasia for each factor were defined by morphological, morphometric, and biochemical methods. All bronchiolar branching, acinar complexity, and acinar maturation were retarded in hypoplastic lungs with hydrops fetalis, renal anomalies, affected side of diaphragmatic hernia, omphalocele, and skeletal anomalies. Only acinar complexity and maturation were impaired in the lung with oligohydramnios due to prolonged rupture of membranes. The pathogenesis of pulmonary hypoplasias should be considered differently with each associated anomaly and time of impairment. While impairment in early gestational stage before 16 weeks' gestation results in both reduced bronchiolar branching and retarded acinar development, that, at late stage, influences only acinar development.

Neurochemical analysis of focal ischemia in rats

BACKGROUND AND PURPOSE

Increases in uric acid follow experimental stroke, which may be related to free radical formation by xanthine oxidase. The present study examined the time course of changes in xanthine and uric acid and their relationship to changes in the free radical scavengers glutathione, cysteine, and ascorbic acid.

METHODS

Focal ischemia was induced by occluding the middle cerebral artery, followed by transient occlusion of the common carotid arteries for 60 minutes. At varying time points, animals were sacrificed, and ischemic cortex was dissected. Neurochemical measurements were made by high-performance liquid chromatography with 16-sensor electrochemical detection.

RESULTS

Marked increases in uric acid were seen at all time points, with a maximal increase at 1 day and a persistent increase lasting up to 21 days. There were smaller reciprocal decreases in xanthine. Glutathione, cysteine, and ascorbic acid showed significant decreases, consistent with the generation of free radicals. Reductions in levels of cysteine and glutathione were significantly correlated with increases in uric acid levels.

CONCLUSIONS

These findings confirm marked alterations in purine metabolism following focal ischemia and suggest that xanthine oxidase contributes to the generation of free radicals.

Association of Epstein-Barr virus with undifferentiated gastric carcinomas with intense lymphoid infiltration. Lymphoepithelioma-like carcinoma

Some undifferentiated gastric carcinomas with intense lymphoid infiltration have a striking resemblance to nasopharyngeal lymphoepithelioma. The authors identified eight such cases (seven patients from Japan and one from the United States) of undifferentiated gastric carcinoma (lymphoepithelioma-like carcinoma [LELC]) and examined them for Epstein-Barr (EBV) viral sequences using polymerase chain reaction (PCR) and in situ hybridization (ISH) techniques. EBV was detected in seven of the eight cases by PCR, including a lymph-node metastasis. ISH that was performed in six of these cases showed EBV genomes to be uniformly present in the carcinoma cells and not present in the reactive lymphoid infiltrate or normal gastric mucosa. PCR of a polymorphic EBV locus (lymphocyte-determined membrane antigen) showed that a single genotype was present in each gastric LELC, consistent with a clonal process. These findings suggest that some undifferentiated gastric carcinomas are EBV-related and that focal EBV infection occurs before transformation.

Expression of three major protein kinase C isozymes in various types of human leukemic cells

We examined the levels of protein kinase C (PKC) activity and the expressions of its three major isozymes, designated types I (gamma), II (beta), and III (alpha), in the cytosol and particulate fractions of cells from patients with acute myelogenous leukemia (AML), acute lymphocytic leukemia (ALL), and chronic lymphocytic leukemia (CLL), in an attempt to elucidate the cell type- or lineage-specific expression of these isozymes. The levels of PKC activities in the cytosol and particulate fractions from AML cells were higher than those from ALL or CLL cells. The average PKC activities of AML cells, ALL cells, and CLL cells were 18.7, 12.2, and 11.3 pmol/min/10(8) cells, respectively, in the cytosol fractions and 4.4, 3.1, and 2.6 pmol/min/10(8) cells, respectively, in their particulate fractions. M1 cells (French-American-British classification) and AML cells with T-lymphocyte-associated surface antigens, such as CD2 and CD7, had significantly lower PKC activities among AML cells. Immunoblot analyses using monoclonal antibodies against each isozyme revealed that all three isozymes were broadly distributed on leukemic cells with considerable variability in the level of expression. All lymphoid leukemic cells expressed PKC-gamma in the cytosol fractions, albeit a minor component; however, this type was observed in cells from only half the number of AML patients. Those AML cells with cytosolic PKC-gamma usually expressed lymphoid surface antigens, such as CD2, CD7, and CD19. On the other hand, cytosolic PKC-beta and PKC-alpha were commonly observed in all types of leukemic cells. AML cells expressed these two types at almost equal levels, but in lymphoid cells, expressions of PKC-beta were usually more abundant than those of PKC-alpha. These data suggest that AML cells with lymphoid antigens might have a lower PKC activity but more predominant expression of cytosolic PKC-gamma than the usual AML cells.

Focal ischemia in rats causes time-dependent expression of c-fos protein immunoreactivity in widespread regions of ipsilateral cortex

c-Fos protein expression was examined in brain by immunohistochemistry following permanent middle cerebral artery (MCA) occlusion above the rhinal fissure and ipsilateral common carotid artery (CCA) occlusion in Long-Evans rats. In sham-operated animals, c-fos protein-like immunoreactivity (CFPLI) was confined to neuronal nuclei of the hypothalamus and was not present in other regions including cerebral cortex. In the core territory of the MCA, CFPLI was not detected when examined at 15 and 30 min, 1, 4 and 8 h and 1, 2, 4 and 7 days after occlusion. Focal ischemia induced two temporal and spatial patterns of CFPLI. At 1 h, c-fos protein was expressed in the nuclei of many neurons in layers II-V of the ipsilateral cortex both immediately adjacent to and remote from the ischemic territory. Within regions outside the MCA territory (e.g. cingulate gyrus and piriform cortices), CFPLI in these neurons peaked at 2-4 h and was undetectable after 2 days. Neurons in the zone immediately surrounding the ischemic core within MCA territory also expressed CFPLI, but in contrast, continued to express c-fos up to 4 days after ischemia. Immunoreactivity surrounding the ischemic core was found in neuronal nuclei predominantly, although from 1 to 4 days, CFPLI was found in perikarya and dendrites as well. MK-801 (3 mg/kg, i.p., 30 min prior to occlusion) completely blocked the early c-fos protein induction in all regions but expression within neurons surrounding the ischemic core was present 1 day after a single injection.(ABSTRACT TRUNCATED AT 250 WORDS)

Characterization of phospholipase A2 (PLA2) activity in gerbil brain: enhanced activities of cytosolic, mitochondrial, and microsomal forms after ischemia and reperfusion

Brain phospholipase A2 (PLA2) activity has not been well characterized. Given the importance of this enzymatic activity for a variety of cellular functions in the brain, we characterized the subcellular distribution of PLA2 activity in gerbil brain and evaluated how PLA2 activity was altered by ischemia and reperfusion. Cytosolic, mitochondrial, and microsomal fractions were prepared by differential centrifugation of forebrain homogenates. PLA2 activities of each fraction were assayed by measuring release of arachidonic acid (AA) from exogenous 14C-AA-phosphatidylcholine (PC), -phosphatidylethanolamine (PE), and -phosphatidylinositol (PI). Two forms of PLA2 were present in the cytosolic fraction: a high-molecular-weight form, active against PC and PE, and a smaller form with an Mr of approximately 14 kDa, active against PE. In the mitochondrial and microsomal fractions, a single form (Mr approximately 14 kDa) was dominant, active against both PC and PE. The role of PLA2 activation in ischemic brain injury remains controversial. PLA2 enzymatic activity was characterized in gerbil brain after 10 min of common carotid occlusion, followed by 10 min of reperfusion. Ischemic/reperfused brains had significantly higher PLA2 specific activities in each subcellular fraction. Ischemia and reperfusion did not change the gel-filtration elution patterns of PLA2 activity of the various forms of the enzyme. Cytosolic, mitochondrial, and microsomal activities were optimal at a pH of approximately 8.5. Cytosolic PLA2 activity was enhanced when Ca2+ concentration [( Ca2+]) was increased over the physiological range (10(-7) to 10(-6) M). Mitochondrial and microsomal PLA2 activities were also [Ca2+] dependent.(ABSTRACT TRUNCATED AT 250 WORDS)

A coenzyme A-independent transacylase is linked to the formation of platelet-activating factor (PAF) by generating the lyso-PAF intermediate in the remodeling pathway

The remodeling pathway for the biosynthesis of platelet-activating factor (PAF) consists of the following reaction sequence: alkylacylglycerophosphocholine----lyso-PAF----PAF. Results presented in this article describe a novel transacylase activity that generates the lyso-PAF intermediate, which can then be acetylated to form PAF. Ethanolamine-containing lysoplasmalogens, 1-acyl-2-lyso-sn-glycero-3-phosphoethanolamine, alkyllysophosphoethanolamine, unlabeled lyso-PAF, 1-acyl-2-lyso-GPC, where GPC is sn-glycero-3-phosphocholine, and choline-containing lysoplasmalogens were all able to stimulate the formation of [3H]lyso-PAF from a [3H]alkylacyl-GPC precursor pool associated with HL-60 cell (granulocytic type) membranes. Other glycerolipids containing free hydroxyl groups (3-alkyl-2-lyso-sn-glycero-1-phosphocholine, lysophosphatidylserine, lysophosphatidylinositol, diacylglycerols, alkylglycerols, and monoacylglycerols), cholesterol, phosphatidylcholine, and phosphatidylethanolamine had no stimulatory effect on the release of [3H]lyso-PAF from the prelabeled membranes under identical incubation conditions. The observed transacylase reaction is directly coupled to PAF production, since the addition of a lysoethanolamine plasmalogen preparation to HL-60 membranes in the presence of [14C]acetyl-CoA stimulated PAF formation; under these conditions the lysoethanolamine plasmalogen was acylated. The transacylase responsible for the release of lyso-PAF from the membrane-associated alkylacyl-GPC was not affected by Ca2+, EGTA, or a known phospholipase A2 inhibitor, p-bromophenacyl bromide. The fact that the unnatural analog of lyso-PAF, lysophosphatidylserine, and lysophosphatidylinositol did not influence transacylase activity, whereas detergents such as deoxycholate and Triton X-100 inhibited the activity, demonstrated the observed stimulatory effects of the choline- and ethanolamine-containing lysophospholipids on the formation of [3H]lyso-PAF from [3H]alkylacyl-GPC were not due to any detergent property of these lysophospholipids. Thus, we conclude a CoA-independent transacylase (possessing phospholipase A2/acyltransferase activities) can be responsible for the formation of the lyso-PAF intermediate in the remodeling route of PAF biosynthesis.

[A case of postpartum fever caused by Mycoplasma hominis infection]

A 26-year-old housewife was admitted to our hospital with a history of high fever after previous cesarean delivery. She had premature rupture of the membrane on the 41st week of pregnancy and the amniotic fluid was found to be cloudy on the fourth day after rupture. Therefore, cesarean delivery was performed. On the first day of operation, her body temperature increased up to 38 degrees C in spite of the treatment with Latamoxef (LMOX), 3 g/day. A sample of intrauterine material yielded M. hominis in pure culture. After administration of Minocycline (MINO) with antimycoplasmal activity, the clinical symptoms improved by the 11th day of operation. Sera obtained after the infection showed antibodies to M. hominis in ELISA study. These results suggested that the cause of this postpartum fever was M. hominis infection.

Cloning, characterization, and physical location of the rplY gene which encodes ribosomal protein L25 in Escherichia coli K12

The rplY gene of Escherichia coli K12 encoding ribosomal protein L25 was cloned from the ordered clone bank and located at coordinate 2,291 kb on the physical map of E. coli. Determination of the nucleotide sequence indicated that the coding region contains 285 nucleotide pairs including a translational initiator and terminator. The amino acid sequence of the protein deduced from the nucleotide sequence matched completely the sequence determined for ribosomal protein L25. The coding region was found to be preceded by a typical promoter-like sequence and was followed by a DNA region capable of forming a secondary structure characteristic of a transcriptional terminator. Thus, the gene was concluded to constitute a transcriptional unit (operon). A preliminary analysis by Northern blot supported this conclusion. The codon usage pattern of the rplY gene is characteristic of the ribosomal protein genes in E. coli.

Characteristics of various synthetic peptide calpain inhibitors and their application for the analysis of platelet reaction

Calpeptin (a cell permeable synthetic peptide calpain inhibitor) inhibited the generation of thromboxane B2 (TxB2) by the direct inhibition on Tx synthetase in platelets at the concentrations more than 30 microM. Calpeptin, its analogues and E-64d (EST) were further examined with regard to cell permiability and inhibitory spectra. Among all compounds, only calpeptin inhibited the degradation of substrate proteins of calpain with negligible effect on TxB2 generation in intact platelets at the concentrations less than 30 microM. These concentrations of calpeptin did not inhibit the platelet aggregation, the elevation of [Ca2+], nor the formation of inositol 1,4,5-trisphosphate (IP3) in thrombin or collagen activated platelets. These results indicate that calpain dose not participate in the process of platelet activation induced by thrombin or collagen.

Global ischemia induces NMDA receptor-mediated c-fos expression in neurons resistant to injury in gerbil hippocampus

The induction of c-fos protein-like immunoreactivity (CFPLI) was examined in the hippocampus of gerbils at several time points after transient global ischemia. c-Fos protein induction was largely confined to the dentate gyrus, CA3 and CA4 regions from 2 to 8 h after transient bilateral carotid occlusion. Little CFPLI was seen in the CA1 subfield, which is disproportionately sensitive to injury after global ischemia. c-Fos induction was completely blocked by pretreatment with MK-801 (3 mg/kg). Our results show that c-fos expression after global ischemia is NMDA receptor mediated, and mainly found in hippocampal neurons resistant to ischemic injury.

Chronic trigeminal ganglionectomy or topical capsaicin application to pial vessels attenuates postocclusive cortical hyperemia but does not influence postischemic hypoperfusion

Marked hyperemia accompanies reperfusion after ischemia in the brain, and may account for the propensity of cerebral hemorrhage to follow embolic stroke or carotid endarterectomy, and for the morbidity that follows head injury or the ligation of large arteriovenous malformations. To evaluate the contribution of trigeminal sensory fibers to the hyperemic response, CBF was determined in 12 symmetrical brain regions, using microspheres with up to five different isotopic labels, in four groups of cats. Measurements were made at 15-min intervals for up to 2 h of reperfusion after global cerebral ischemia induced by four-vessel occlusion combined with systemic hypotension of either 10- or 20-min duration. In normal animals, hyperemia in cortical gray matter 30 min after reperfusion was significantly greater after 20 min (n = 10) than after 10 min (n = 7) of ischemia (312 ml/100 g/min versus 245 ml/100 g/min; p less than 0.01). CBF returned to preischemic levels approximately 45 min after reperfusion and was reduced to approximately 65% of basal CBF for the remaining 75 min. In cats subjected to chronic trigeminal ganglionectomy (n = 15), postocclusive hyperemia in cortical gray matter was attenuated by up to 48% on the denervated side (249 versus 150 ml/100 g/min; p less than 0.01) after 10 min of ischemia. This effect was maximal in the middle cerebral artery (MCA) territory, and was confined to regions known to receive a trigeminal innervation. In these animals, substance P (SP) levels in the MCA were reduced by 64% (p less than 0.01), and the density of nerve fibers containing calcitonin gene-related peptide (but not vasoactive intestinal polypeptide or neuropeptide Y) was decreased markedly on the lesioned side. Topical application of capsaicin (100 nM; 50 microliters) to the middle or posterior temporal branch of the MCA 10-14 days before ischemia decreased SP levels by 36%. Postocclusive hyperemia in cortical gray matter was attenuated throughout the ipsilateral hemisphere by up to 58%, but the cerebral vascular response to hypercapnia (PaCO2 = 60 mm Hg) was unimpaired. The duration of hyperemia and the severity of the delayed hypoperfusion were not influenced by trigeminalectomy, capsaicin application, or the intravenous administration of ATP. These data demonstrate the importance of neurogenic mechanisms in the development of postischemic hyperperfusion, and suggest the potential utility of strategies aimed at blocking axon reflex-like mechanisms to reduce severe cortical hyperemia.

Characterization of two human lymphoid cell lines producing human T-lymphotropic virus type I (HTLV-I) isolated from patients with HTLV-I-associated myelopathy or encephalopathy

Two cell lines, CNS-5 and CNS-6, were established by cocultivation of sedimented cells in cerebrospinal fluid (CSF) from two anti-human T-lymphotropic virus type I (HTLV-I) antibody-positive male patients with encephalopathy and HTLV-I-associated myelopathy, respectively, with peripheral blood mononuclear cells from a healthy seronegative female. These cell lines, possessing a normal female karyotype, revealed similar characteristics as follows; they expressed HTLV-I-related antigens, they produced C-type retrovirus particles, HTLV-I provirus genomes were integrated into their DNAs, and they had CD4+ activated T-cell markers. In addition, immunocytochemical and immunoelectron microscopic studies showed peculiar immunoreactivity of these cell lines with anti-alpha/beta T-cell antigen receptor (TCR) antibodies; beta Fl, defining beta chain epitope, was only positive in the perinuclear spaces and rough endoplasmic reticulum in some cells, and WT31, recognizing alpha/beta framework, was mostly negative, while CD3 was expressed in the majority of the cells. These facts indicate that HTLV-I-infected cells were present in CSF of these two patients, and suggest that neurological disorders associated with HTLV-I may not be restricted to myelopathy and may include brain abnormalities.

Organic Ca(2+)-antagonist-resistant response to FMRF-NH2 on the molluscan smooth muscle

1. FMRF-amide (10(-7)-10(-5) M) contracted molluscan anterior byssus retractor muscle in a concentration-dependent fashion. 2. The concentration-response curve of FMRF-amide was shifted rightward by an analogue of FMRF-amide, FMRf-amide ([D-Phe4]FMRF-amide, putative FMRF-amide receptor antagonist) in a parallel manner (pA2 = 4.87 +/- 0.04). 3. Although a contractile response to KCl was reduced by the organic Ca2+ antagonists (verapamil, diltiazem and high concentration of nifedipine and nicardipine). FMRF-amide-induced contraction was not markedly reduced by them. 4. In the Ca(2+)-free medium, FMRF-amide-induced contraction was diminished. The response was also reduced by TMB-8 (10(-4) M), suggesting that FMRF-amide-induced contraction might be partly dependent on intracellular Ca2+. 5. An inorganic Ca(2+)-antagonist, MnCl2, markedly reduced the FMRF-amide- and KCl-induced contraction. The results show that FMRF-amide-induced contraction might be dependent on extracellular Ca2+. 6. These findings suggest that FMRF-amide-induced contraction might be mediated through an action on FMRF-amide receptors and not through the activation of organic Ca2+ antagonist-sensitive Ca2+ channels.

[Characterization of the factor VIII inhibitor in a patient with chronic renal failure]

A 29-year-old women, who had been treated by hemodialysis for 5 years because of chronic renal failure, developed bleeding tendency in March 1989. Laboratory data showed prolonged activated partial thromboplastin time which was not corrected by addition of normal plasma; factor VIII activity was less than 1% and factor VIII inhibitor 70 Bethesda units/ml. The inhibitor was eluted in the second peak which corresponded to IgG when the plasma was subjected to Sephacryl S 200 column. The further purified IgG fraction by passing through protein A column showed a factor VIII inhibitor activity of 52 Bethesda units/ml. The factor VIII inhibitor epitopes were examined by western blotting technique using factor VIII purified by monoclonal antibody as the antigen. The factor VIII preparation used was composed of a doublet of light chain (Mr 80,000) and three heavy chains (Mr 160,000-200,000) when examined by immunoblotting using anti-factor VIII light and heavy chains monoclonal antibodies after SDS-PAGE. Factor VIII inhibitor that arose in a hemophilia A patient recognized the light chain, and the inhibitor in this case reacted to the heavy chain of factor VIII.

[Left ventricular function after prolonged exercise]

To determine whether depressed left ventricular (LV) contractile function can occur after exhaustive exercise, echocardiographic studies were performed in eleven athletes before, at the finish (9 minutes) and during recovery (15 hour) after the Biwa Lake Ironman Triathlon (3.2 km Swim, 161 km Bike, 32 km Run). Before racing and during recovery, the studies were performed both at rest and after brief exercise (10-15 minutes). Heart rates after brief exercise were comparable to those attained after racing. Digitized M mode echocardiographic data as to wall thickness, cavity dimension, fractional shortening (FS) and peak circumferential shortening (maxVcf) were obtained. When we compared race finish to pre-race brief exercise, the LV end-diastolic dimension (EDD) was reduced (46 +/- 7 vs 47 +/- 6 mm, less than 0.05) and FS declined (33 +/- 5 vs 39 +/- 6%, p less than 0.05). In spite of reduced wall stress, maxVcf decreased. Individual percent reductions in FS were not correlated with decrease in EDD, but correlated with increases in EDS. Although a persistent reduction in cavity size was observed during recovery, FS and maxVcf returned toward the baseline. The results suggest that prolonged strenuous exercise may result in impaired LV function in part because of a reversible depression in the contractile state.

Selection of monoclonal antibodies detecting KM01 antigen

Monoclonal antibodies (MoAbs) were selected for specific binding inhibition of KM01 to the KM01 antigen, which was detected in the serum of colorectal and other gastrointestinal carcinoma patients. Out of 91 MoAbs tested, 8 were found to have the inhibiting activity. The reactivity of these MoAbs with glycolipid antigen, which was isolated from cancer cell line, corresponded well with that of cancer patients sera. These monoclonal antibodies are thought to be useful in combination with KM01 for the construction of the second generation of the KM01 antigen-detecting system.

Platelet protein phosphatases and their endogenous substrates

One p-nitrophenyl phosphate phosphatase (A) and five protein phosphatases (B, C, D, E, F) with neutral pH optimum (7.0-7.5) were partially purified from human platelets. Protein phosphatases were activated by Mn2+ (B-F), Mg2+ (D, F) or Ca2+ (F) but all of them had substantial activity even in the presence of EDTA. The activity of phosphatase D was predominant when assayed in the presence of EDTA. Phosphatase F was significantly enhanced by Ca2+ and calmodulin and therefore considered to be calcineurin. Without strict substrate specificity, all protein phosphatases (B-F) dephosphorylated phosphoproteins like actin binding protein, 47k protein and myosin light chain. Thus, it was suggested that protein phosphatases might play a role in the down regulation of platelet function not only in the resting but agonist-stimulated platelets.

[A case of complete remission from acute unclassified leukemia achieved by using a prodrug of ara C, stearyl-ara-CMP (YNK01)]

YNK01 (a daily oral dose of 450 mg) was administered for 22 days to a 58-year-old-female with Ph1-positive acute unclassified leukemia. Leukemia cells were negative for peroxidase and esterase, but were positive for CD19, CD13, CD34, CD9, HAL-DR, CD25, and TdT. Complete remission was obtained and continued for at least a month. The main side effects noted were diarrhea and melena. The administration of YNK01 resulted in plasma ara C levels that ranged between 15.4 to 23.0 ng/ml, which appear to be nearly equivalent to dose achieved during continuous IV infusion of a low dose (20 mg/m2/day) of ara C.

[Successful treatment of primary myelofibrosis by busulfan pulse therapy: report of a case]

Idiopathic myelofibrosis is a disease of unknown cause characterized by systemic marrow fibrosis and extramedullary hematopoiesis. We report here a patient of myelofibrosis treated successfully by busulfan pulse therapy which was reported first by chang et al in 1988. The patient was a 62-year-old woman who was referred to us for anemia and hepatosplenomegaly in August 1984. Further examination established a diagnosis of idiopathic myelofibrosis. During the subsequent 4-year follow-up period without specific treatment in our outpatient clinic, there occurred gradual progression of anemia and hepatosplenomegaly with the spleen extending beyond the level of the umbilicus. In September 1988, she was initiated on 4-day pulse therapy of busulfan with a daily dose of 12 mg, which was repeated 10 times until July 1989. This was followed by marked improvement of anemia and hepatosplenomegaly. Post-treatment iliac marrow biopsy showed some reduction of reticulin fibers with increased hematopoietic elements as compared to pretreatment iliac marrow biopsy. The busulfan pulse therapy, therefore, appears to be a treatment of choice in idiopathic myelofibrosis.

Characterization of an antigen defined by monoclonal antibody KMO1

We have isolated an antigen defined by the monoclonal antibody KMO1 from tissue culture supernatant as a glycoprotein and from cancer cells as a glycolipid. The antigenic determinant was a carbohydrate. Antibody KMO1 inhibited the binding activity of 19-9 to CA19-9, but 19-9 antibody did not inhibited the binding activity of KMO1 to KMO1 antigen. The glycolipid antigen of KMO1 was a monosialoganglioside and was separated into 3 components on thin layer chromatography. The 19-9 antibody reacted with one of the components. These results suggest that the KMO1 antigen is similar to but not identical to CA19-9.

Origins and distribution of cerebrovascular nerve fibers showing calcitonin gene-related peptide-like immunoreactivity in the major cerebral artery of the dog

The origins and overall distribution of perivascular nerve fibers showing calcitonin gene-related peptide-like immunoreactivity (CGRP-LI) in the major cerebral arteries were investigated immunohistochemically in the dog by using whole-mount preparations of the arterial trees around the circle of Willis. Perivascular nerve fibers with CGRP-LI were seen most abundantly in the basilar artery, vertebral artery, common anterior cerebral artery, proximal part of the anterior cerebral artery, and terminal part of the internal carotid artery. They were far less numerous in the middle cerebral artery, posterior cerebral artery, superior cerebellar artery, and distal part of the anterior cerebral artery. Neuronal cell bodies with CGRP-LI were observed in the trigeminal, nodose, superior cervical, and dorsal root ganglia. CGRP-LI fibers in the large pial arteries in the circle of Willis were eliminated ipsilaterally after unilateral transection of the ophthalmic division of the trigeminal nerve, and slightly reduced in number ipsilaterally after unilateral transection of the maxillary division of the trigeminal nerve. They did not show any noticeable changes after unilateral transection of the mandibular division of the trigeminal nerve. On the other hand, CGRP-LI fibers in the basilar and vertebral arteries did not show any appreciable changes after unilateral transection of the trigeminal nerve, but they were eliminated after bilateral ganglionectomy of the dorsal root ganglia of the first, second, and third cervical nerves. After ganglionectomy of the ciliary, pterygopalatine, otic, nodose, or superior cervical ganglion, no changes were observed in perivascular nerve fibers with CGRP-LI in the major cerebral arteries.(ABSTRACT TRUNCATED AT 250 WORDS)

[DNA diagnosis of Leber's hereditary optic neuropathy]

The point mutation at nt11778 in mitochondrial DNA is highly associated with Leber's hereditary optic neuropathy and eliminates a restriction enzyme SfaNI site in American blacks and Caucasians. DNA diagnosis was applied to a male Japanese patient with this disorder and his mother as a carrier. The mitochondrial DNA fragments (255bp) including this mutation were amplified by polymerase chain reaction. SfaNI digested the DNA fragments of normal Japanese subjects, but did not digest those of the patient or the carrier, The mutation within the SfaNI site is also associated with Japanese suffering from this disorder.

Selective sparing of NADPH-diaphorase-somatostatin-neuropeptide Y neurons in ischemic gerbil striatum

In the present study we investigated the relative vulnerability of neuronal subsets in the striatum to ischemia that was induced by bilateral transient ligation of the common carotid arteries in gerbils. After 4 days of survival, brains were evaluated using histochemical methods (NADPH-diaphorase and silver degeneration procedures) and neurochemical methods with radioimmunoassays for somatostatin-, neuropeptide Y-, and substance P-like immunoreactivity and measurements of amino acids using high-pressure liquid chromatography with electrochemical detection. NADPH-diaphorase-positive neurons were strikingly preserved in the ischemic dorsolateral portion of the striatum, in which there was severe neuronal loss. There was no significant depletion of NADPH-diaphorase-positive neurons in the striatum or cerebral cortex. Concentrations of neuropeptide Y-like and somatostatin-like immunoreactivity were unchanged despite a significant 25% depletion of substance P-like immunoreactivity and gamma-aminobutyric acid. Ischemic brain damage may be mediated by a neurotoxic effect of glutamate acting at the N-methyl-D-aspartate (NMDA) receptor. Previous studies of NMDA excitotoxin lesions in rat striatum have shown a sparing of neurons containing NADPH-diaphorase, somatostatin, and neuropeptide Y. The similar sparing of these neurons following ischemic lesions in gerbil striatum provides further evidence that NMDA receptor activation may play a role in ischemic injury.

Vascular relaxation properties of calcitonin gene-related peptide and vasoactive intestinal polypeptide in subarachnoid hemorrhage

The vascular relaxation effects of calcitonin gene-related peptide (CGRP) and vasoactive intestinal polypeptide (VIP) on the dog basilar artery after experimentally produced subarachnoid hemorrhage (SAH) were examined in vitro by an isometric tension recording method. Both CGRP and VIP induced dose-dependent relaxations in ring segments of the intact basilar artery of control dogs. The vasorelaxant action of CGRP was more potent than that of VIP. The single-injection model of SAH was produced by injection of fresh autologous arterial blood (1 ml/kg body weight) into the cisterna magna on Day 0 of the post-SAH period, and the double-injection model was produced by two injections of blood (0.5 ml/kg each) on Days 0 and 2. Narrowing of the basilar arteries on vertebral angiograms was most prominent on Day 3 or 7 in the single- or double-injection model, respectively. Relaxation of the basilar artery induced by CGRP and VIP was to some extent decreased on Days 3 and 7 of the post-SAH period in the single-injection model, and on Days 7 and 14 in the double-injection model. However, the vasorelaxant effects of CGRP and VIP were significantly enhanced on Day 14 of the post-SAH period in the single-injection model, and on Days 28 and 42 in the double-injection model. Subsequently, these effects returned to control levels by Days 28 or 63 in the single- or double-injection model, respectively.

Development of monoclonal antibodies against human gastrointestinal cancer

We have evaluated approximately 10,000 monoclonal antibodies resulting from 14 hybridization of spleen cells from mice immunized with established cancer cell lines. They were screened by binding assays using cancer cell lines or normal fibroblast cells, followed by immunohistochemical study on tissue sections. Ninety-one monoclonal antibodies were obtained by above binding assays. One of them, named KM10 was further investigated. Isotype of KM10 was IgG1 with kappa-light chain. It was shown that KM10 has strong reactivity with tumors of colon, stomach, papilla Vater, and pancreas, while the limited reactivity displayed with normal tissues. The electron microscopic observation revealed that the antigen recognized by KM10 is expressed on the surface of cancer cells. KM10 could mediate ADCC. These results indicate that KM10 is a good candidate for a probe of diagnosis and therapy of cancer.

Erythrocytes suppress calcitonin gene-related peptide- and vasoactive intestinal polypeptide-like immunoreactivities in cerebrovascular nerve fibers after subarachnoid hemorrhage

Changes of calcitonin gene related-peptide (CGRP)- and vasoactive intestinal polypeptide (VIP)-like immunoreactivities (LI) in cerebrovascular nerve fibers on the dog basilar artery were immunohistochemically examined by using whole-mount preparations after single percutaneous injection of blood components into the cisterna magna. Blood components were prepared from autologous arterial blood. CGRP- and VIP-LI in cerebrovascular nerve fibers were highly suppressed after the injection of washed erythrocytes, but only moderately after the injection of platelet-rich or platelet-poor plasma. The results suggest that erythrocytes may suppress CGRP- and VIP-LI in cerebrovascular nerve fibers after subarachnoid hemorrhage.

Changes of glycogen and ATP contents of the major cerebral arteries after experimentally produced subarachnoid haemorrhage in the dog

The contents of glycogen and ATP in the major cerebral arteries were examined in dogs undergoing subarachnoid haemorrhage (SAH). SAH was produced by a single injection of autologous arterial blood (1 ml/kg body weight) into the cisterna magna. Vertebral angiograms showed biphasic basilar arterial narrowings after the injection of blood: Early arterial narrowing occurred immediately after the injection and continued for a few hours. Late arterial narrowing occurred from Day 1 to Day 14 of post-SAH period, and recovered to the normal level on Day 21 of post-SAH period. The content of glycogen in the large pial arteries significantly decreased from Day 1 to Day 14 and returned to the control level on Day 21. The content of ATP in the large pial arteries also decreased from Day 1 to Day 7 and returned to the control level on Day 14. These results show that energy stores in the major cerebral arteries might be diminished during late arterial narrowing.

Decreased expression of type II protein kinase C in HL-60 variant cells resistant to induction of cell differentiation by phorbol diester

To evaluate the molecular basis for susceptibility of the cell differentiation induced by 12-O-tetradecanoylphorbol-13-acetate (TPA), we examined biochemical activities and expression of subspecies of protein kinase C from HL-60 cells that are susceptible to differentiation induced by TPA and HL-60R cells, HL-60 variant cells that are resistant to such induction. Analysis of the subcellular distribution of protein kinase C revealed that the activity of this kinase in the cytosol from HL-60R cells was 30% of that from parental HL-60 cells but that the enzyme activities in the membrane showed similar values in these cells. Treatment of HL-60 cells with 100 nM TPA for 30 min resulted in a 75% decrease in protein kinase C activity in the cytosol and a 300% increase in this activity in the membrane. A minor subcellular redistribution of the enzyme activity was found in HL-60R cells after TPA treatment. Based on analysis of protein kinase C isozymes by hydroxyapatite column chromatography, the relative activities of types I, II, and III in the cytosol of HL-60 cells were 11, 80, and 9%, whereas those in HL-60R cells were 27, 36, and 37%, respectively. Type II isozyme was a major protein kinase C in the cytosol of HL-60 cells, but type II was less in the HL-60R cells. Among the three isozymes, type II enzyme was most sensitive to TPA with histone H1 as the substrate, although all three isozymes were activated Ca2+-dependently in the presence of phosphatidylserine. We suggest that the acquired resistance of HL-60R cells toward induction of cell differentiation by TPA may be associated with a decrease in the expression of the type II isozyme of protein kinase C.