A rare case of ectopic antidiuretic hormone-producing pancreatic adenocarcinoma: new diagnostic approach

We describe a 73-year old man with the syndrome of inappropriate antidiuretic hormone secretion (SIADH) due to an ectopic ADH-producing pancreatic adenocarcinoma. His laboratory findings showed marked hyponatremia, and the water load test showed uncontrolled ADH secretion. The imaging studies revealed pancreatic body cancer. Histological examination revealed an adenocarcinoma of the pancreas, which was positive for ADH immuno-staining. The ADH in the tumor extract was 53.3 pg/g wet weight. In attempt to diagnose ADH-production from the tumor, the ADH in his pancreatic juice was measured and found to be 2.1 pg/ml. We conclude that it is valid to measure the ADH in pancreatic juice to diagnose ectopic ADH production by tumors.

Antiplatelet and antithrombotic effects of YM337, the Fab fragment of a humanized anti-GPIIb/IIIa monoclonal antibody in monkeys

The antiplatelet and antithrombotic effects of the Fab fragment of the humanized antiplatelet glycoprotein (GP) IIb/IIIa monoclonal antibody C4G1 (YM337) were investigated in monkeys. First, the relationship between the inhibition of platelet aggregation and the prolongation of bleeding time was studied in rhesus monkeys. YM337 dose-dependently inhibited ex vivo platelet aggregation, with complete inhibition at doses higher than 0.25 mg/kg intravenous injection or 1.5 micrograms/kg/min infusion. At 0.25 mg/kg bolus injection followed by 1.5 micrograms/kg/min infusion, YM337 immediately and continuously inhibited platelet aggregation during the 6-h infusion period with platelet aggregation rapidly returning to over 50% of baseline within 1 h after the cessation of infusion. Template-bleeding time was significantly prolonged during the period of complete inhibition of platelet aggregation. Second, the antithrombotic effects of YM337 were investigated in a photochemically-induced thrombosis model in squirrel monkeys. YM337 at a dose of 1 mg/kg intravenous injection followed by 6 micrograms/kg/min infusion for 60 min prevented occlusive thrombus formation in all 4 monkeys. In contrast, time to occlusive thrombus formation did not change on intravenous bolus injection of aspirin 17 mg/kg (11.3 +/- 5.2 min) or sodium ozagrel (9.4 +/- 3.0 min) compared with saline (13.3 +/- 4.0 min). YM337 but not aspirin or sodium ozagrel significantly inhibited ex vivo ADP-induced platelet aggregation, while all drugs completely inhibited arachidonic acid-induced platelet aggregation. However, while aspirin and sodium ozagrel inhibited the thromboxane B2 generation accompanying arachidonic acid-induced platelet aggregation, YM337 had no effect on this variable. Platelet counts and bleeding time showed no significant change in any group in this squirrel monkey model. These results indicate that YM337, with a short half-life, may be a useful therapeutic agent in patients with thrombotic disorders.

Plasma hepatocyte growth factor levels are increased in systemic inflammatory response syndrome

Interleukin-1 (IL-1), a cytokine released from macrophages by endotoxin stimulation, has been shown to upregulate the genetic expression of the hepatocyte growth factor (HGF). The present study was conducted to determine whether plasma HGF is increased in patients with systemic inflammatory response syndrome (SIRS). The plasma levels of HGF, endotoxin, and beta-glucan were measured in 41 surgical patients without hepatic diseases, 18 of whom had been diagnosed with sepsis, and 33, with nonseptic SIRS. The plasma HGF was found to be significantly increased in the 18 patients with sepsis, at 0.69 +/- 0.47 ng/ml (mean +/- SD), and in the 23 patients with nonseptic SIRS, at 0.49 +/- 0.37 ng/ml, compared to values in 40 normal controls, at 0.10 +/- 0.03 ng/ml (P < 0.001). No significant correlations were observed between the plasma levels of HGF and endotoxin (r = 0.02) or beta-glucan (r = -0.05) in any of the patients; however, plasma HGF was significantly correlated with the WBC count (r = 0.34, P < 0.05) and with total bilirubin (r = 0.45, P < 0.01). Plasma HGF was also strongly correlated with alanine transaminase (ALT) in 8 patients with ALT levels higher than 50 U/l (r = 0.70), but there was no such correlation in 33 patients with ALT levels of 50 U/l or less (r = 0.30). Thus, although the clinicopathologic significance of HGF is not well understood, the present findings indicate that plasma HGF increases in response to infection or inflammation.

Hemostasis activation during sclerotherapy of lower extremity varices

The influence of compression sclerotherapy upon hemostasis activation was investigated in 41 consecutive patients with lower extremity varices by serial measurement of thrombin-antithrombin III complexes (TAT), D-dimer, fibrinogen and C-reactive protein (CRP). Blood sampling was carried out before operation and on the 7th and 28th post-operative day in patients randomly assigned to either the control group (n = 18), in which high ligation of sapheno-femoral junction and local excision of varices were performed, or the sclerotherapy group (n = 23) in which the comparable surgical intervention and compression sclerotherapy using hypertonic saline were performed simultaneously. In both groups, the TAT, D-dimer and fibrinogen concentrations at day 7 were significantly elevated compared to the value before operation while CRP showed no significant change during the observation period. In the sclerotherapy group, higher incidence of superficial thrombosis was observed and the TAT concentration at day 7 was significantly higher than that in the control group (p < 0.01), and the TAT at day 28 was still significantly elevated compared to the pre-operative level (p < 0.05). However, no relationship between TAT and D-dimer concentrations and the extent of superficial thrombosis was observed. We conclude that compression sclerotherapy for lower extremity varices causes latent activation of coagulation system and can be a risk factor for venous thromboembolism.

[Comparison of diet, physical activity and serum lipids between Chinese and Japanese: Chengdu-Fukuoka Study]

A detailed diet history was taken from 326 Chinese adults, 116 college students in Chengdu, China, and 300 Japanese adults and 4529 college students in Fukuoka, Japan. Both populations consume high carbohydrate and low fat diet, but the Chinese diet was higher in carbohydrate, cereal energy/total energy ratio and polyunsaturated fatty acids/saturated fatty acids ratio, and lower in protein, fat and animal fat/total fat ratio compared to the Japanese diet. Cholesterol intake was significantly lower in Chinese than in Japanese (P < 0.001). Physical activity index in Chinese was higher than that in Japanese. Serum lipids and lipoprotein cholesterols were measured in the adults of Chinese and Japanese. Except the serum triglycerids level in female, the total cholesterol, TG, high density lipoprotein-cholesterol and low density lipoprotein-cholesterol levels in Chinese adults were lower than those in Japanese adults (P < 0.001). Since cholesterol is the major predisposing factor for coronary heart disease and the results of our study show that a high carbohydrate and low fat diet can be effective in lowering the cholesterol level in blood it will be of interest to see which kind of oriental dietary may be a preventive against coronary heart disease.

A unique CD45 glycoform recognized by the serum mannan-binding protein in immature thymocytes

The serum-mannan binding protein (S-MBP) is a calcium-dependent C-type lectin specific for mannose and N-acetylglucosamine. S-MBP is known as a host defense factor involved in innate immunity, where the target ligands for S-MBP should be on the surface of exogenous microorganisms. In this study, we tried to find endogenous ligands for this endogenous lectin. Among the cells tested, only the lymphocytes from thymus of BALB/c mice expressed ligands for S-MBP on their surface, those from bone marrow, spleen, mesenteric lymph nodes and peripheral blood all being negative. Interestingly, among the thymocytes, only the immature thymocytes with the CD4+CD8+CD3low phenotype expressed ligands for S-MBP, and ligands for S-MBP decreased on their maturation. A major cell surface glycoprotein bearing S-MBP ligands was isolated and identified as CD45RO, which is a transmembrane protein with tyrosine phosphatase activity. Deglycosylation experiments with N-glycanase and endoglycosidase H indicated that the S-MBP ligands on thymic CD45 are high mannose type or hybrid type N-linked oligosaccharides. This unique presentation of S-MBP ligands on this special CD45 isoform suggested the possibility that the oligosaccharide portion of CD45 on immature thymocytes is associated with the maturation, development or selection events of thymocytes.

Primary structure of alboaggregin-B purified from the venom of Trimeresurus albolabris

The complete amino acid sequences of alpha and beta subunits of alboaggregin-beta are presented. The alpha and beta subunits were separated by reversed-phase HPLC after reduction and S-pyridylethylation, and their sequences were determined by analysis of peptides generated by enzymatic or chemical digestion. The alpha and beta subunits consist of 133 and 123 amino acid residues, respectively. The sequences are highly homologous to each other (41.4% identity) and also to those of the alpha and beta subunits of botrocetin (a von Willebrand factor modulator) and the A and B chains of factor IX/X binding protein from other snake venoms. It is also homologous to C-type lectins with a homodimeric structure, but it shows no lectin-like activity.

[Three cases of drug-induced hemolytic uremic syndrome]

We report three cases of drug-induced hemolytic uremic syndrome (HUS). Three patients with advanced gastrointestinal cancer underwent a curative operation and adjuvant chemotherapy with Mitomycin C (MMC), 5FU and Ara-C. Later, progressive anemia, thrombocytopenia, renal dysfunction and elevation of serum LDH were recognized. A diagnosis of HUS was made. As they had no symptoms of infectious diseases or relapse of cancer, the cause of HUS was thought to be MMC. Treatment with antiplatelet drugs and fresh frozen plasma was effective for two patients. However, one patient died of pulmonary edema.

Lumboperitoneal shunt for cauda equina syndrome in ankylosing spondylitis

Cauda equina syndrome is a rare complication in the late stage of ankylosing spondylitis, for which approximately 60 cases have been reported in the literature. The cause of the syndrome is unclear, and there is no effective treatment. Recently lumboperitoneal shunt was reported to have been effective in two patients. In our study, we performed lumboperitoneal shunt in a patient and evaluated the condition after the operation compared with that preoperatively. Some alleviation of neurologic symptoms was observed for 6 months after operation. Histopathologic examination of the dural diverticulum revealed a residual change after old inflammation. Lumboperitoneal shunt was an effective surgical treatment for cauda equina syndrome in this patient with ankylosing spondylitis, but its effects were not extreme. Arachnoiditis is suggested to be involved in the pathogenesis of cauda equina syndrome.

The relationship between the intrauterine environment and blood pressure in 3-year-old Japanese children

In 195 Japanese children the systolic pressure at 3 years of age was inversely correlated to the body weight at birth and positively correlated to the mothers' systolic pressure during pregnancy: the average systolic pressure in children whose body weight at birth exceeded 3510 g was 3.0 mmHg, which was lower than that of children whose body weight at birth was 2990 g or less. There was an increase of 0.12 mmHg in the children's systolic pressure with each increment of 1 mmHg in the systolic pressure of their mothers. The systolic pressure at 3 years in children of mothers who had had pretibial oedema during pregnancy (101.0 +/- 8.8 mmHg) was significantly higher compared with children whose mothers did not have oedema (96.6 +/- 9.6 mmHg).

Involvement of protein phosphatase 2A in PKC-independent pathway of neutrophil superoxide generation by fMLP

We examined the effects of okadaic acid, a protein phosphatase 1 and 2A inhibitor, on superoxide generation in human neutrophils. Superoxide generation induced by fMLP was inhibited by low-dose okadaic acid (10-100 nM), but it had no effect on superoxide synthesis by PMA, and the fMLP-induced rise of the intracellular Ca2+ concentration was not affected by low-dose okadaic acid. These findings suggested that the inhibitory mechanism of okadaic acid might involve PKC-independent and Ca(2+)-independent pathways in fMLP induced NADPH oxidase activation. Both fMLP-stimulated phosphorylation of serine residues in p47phox and its translocation to the plasma membrane were suppressed by low-dose okadaic acid. On the other hand, PMA-induced phosphorylation and translocation of p47phox were not affected by such a low dose of okadaic acid. These findings suggested that fMLP induced phosphorylation of serine residues in p47phox was regulated by protein phosphatase 2A, and its phosphorylation was necessary for translocation and superoxide generation in fMLP-activated human neutrophils.

Correlation between integrin alpha 5 expression and the malignant phenotype of transitional cell carcinoma

We examined the expression of alpha 1, alpha 2, alpha 3, alpha 4, alpha 5 and beta 1 integrin on 36 transitional cell cancers (TCCs) in the bladder by immunohistochemistry. Only alpha 2, alpha 3 and beta 1 were detected on normal transitional cell epithelium, but four TCCs (12.5%) revealed positive staining for alpha 1, seven (19.4%) for alpha 4 and seven (20%) for alpha 5. These altered expressions of integrin alpha chain were more frequent in histologically higher stage or grade of TCC, and a correlation was found between increased alpha 5 expression and histological stage. alpha 5 was positive in 6 (35.3%) of 17 invasive TCCs whereas only 1 (5.9%) of 17 superficial TCCs. Flow cytometric analysis on bladder cancer cell lines showed that T24 and HT1376, which are undifferentiated TCC cell lines, highly expressed alpha 5 and beta 1. Also, SCaBER, which is derived from urinary bladder squamous cell cancer and which is recognised as the most malignant phenotype after metaplasia of transitional epithelium, had alpha 5 and beta 1. However, RT4, which is derived from transitional cell papilloma, showed no expression of alpha 5. Furthermore, reverse transcriptase-polymerase chain reaction (RT-PCR) showed the presence of mRNA of alpha 5 on T24, SCaBER and HT1376, but not on RT4. Taken together, it seems that the presence of alpha 5 integrin might be a more malignant phenotype in transitional cell carcinoma.

Functional neuroanatomy of visual object naming: a PET study

BACKGROUND

The ability to name objects depends partly on visual perception. We used positron emission tomography (PET) to measure activity-related changes in regional cerebral blood flow (r-CBF) in order to identify regions of the brain activated during visual object naming.

METHODS

Four right-handed volunteers were recruited. Following an intravenous injection of 15O-labeled water, r-CBF was measured during visual object naming, counting numbers, and resting. PET and MRI images were coregistered, the size of the brain was proportionally adjusted in each axis to Talairach's and Tournoux's atlas, and the comparison of stimulated versus resting blood flow images revealed activated brain regions.

RESULTS

In the subtraction of resting from naming, activation was observed in the bilateral primary visual cortex, bilateral fusiform gyrus, left lingual gyrus, bilateral inferotemporal cortex, bilateral inferior frontal gyrus, bilateral precentral gyrus, anterior cingulate gyrus, left parietal operculum, and left putamen. In the subtraction of counting from naming, most of the those areas were activated, but no significant activity was observed in the left lingual gyrus, left parietal operculum, or bilateral precentral gyrus (motor cortex). The areas activated with the paradigm included those dedicated to visual perception (primary and associate visual cortex), visual recognition (inferior temporal cortex), and phonological output (Broca's area).

CONCLUSION

Our results indicated that the major neural network from occipital lobe to frontal cortex, which is mainly involved in the ventral visual pathway, demonstrated activation in these tasks. Result of this study will serve as base line data for analyzing the findings in patients with impaired visual perception.

Platelet microparticles: a carrier of platelet-activating factor?

Platelet-activating factor (PAF) has been considered to be released in a soluble form from activated platelets. Also a considerable number of microparticles were released from stimulated platelets. To evaluate the possibility that microparticles contain PAF, the amount of PAF in whole activated platelets, microparticles and the suspending medium was determined by means of bioassay. The total amount of PAF released from 3 x 10(8) platelets activated with thrombin (0.5 U/ml) plus collagen (10 micrograms/ml) for 10 minutes was 4.6 +/- 1.5 x 10(-12) mol (n = 8, mean +/- S.D.). Eighty-seven percent of the PAF released from platelets was associated with microparticles. PAF released in microparticles is susceptible to plasma acetylhydrolase and may be localized on the outer surface of microparticles. This is the first report implicating the role of microparticles as a novel carrier of mediators formed in the cells.

Dual roles of sphingolipids in signaling of the escape from and onset of apoptosis in a mouse cytotoxic T-cell line, CTLL-2

In our previous study, the sphingosine-like immunosuppressant, ISP-1, was found to suppress the proliferation of an interleukin-2-dependent cytotoxic T cell line, CTLL-2, through the inhibition of serine palmitoyltransferase, which catalyzes the committed step of sphingolipid biosynthesis. Analysis of the effect of ISP-1 by flow cytometry revealed that the ISP-1-dependent decrease in cell number was not due to inhibition of the cell cycle progression of CTLL-2 cells but to the induction of apoptosis of the cells. The ISP-1-induced apoptosis was inhibited by the addition of sphingosine (2 microM), suggesting that this ISP-1-induced apoptosis is triggered by the decrease in the intracellular levels of sphingolipids caused by the inhibition of serine palmitoyltransferase. However, another interleukin-2-dependent cell line, F7, which was derived from a mouse pro-B cell line, did not show ISP-1-dependent apoptosis, indicating that the effect of ISP-1 may be specific for a certain type of T cell lineage such as CTLL-2. On the other hand, a high dose of sphingosine (5 microM) by itself induced the apoptosis of CTLL-2 cells. This sphingosine-dependent apoptosis was also observed with F7 cells. These results provide evidence that the intracellular levels of sphingolipids play an important role in the signaling of the escape from and onset of apoptosis of CTLL-2 cells.

Biochemical characterization of a new disintegrin, flavostatin, isolated from Trimeresurus flavoviridis venom

We biochemically characterized a new disintegrin, flavostatin, isolated from Trimeresurus flavoviridis venom. Flavostatin inhibited ADP-, collagen-, and thrombin receptor agonist peptide-induced platelet aggregation in human platelet-rich plasma (IC50 range: 59 to 111 nM) and blocked the binding of biotinylated human fibrinogen to purified GPIIb/IIIa with an inhibitory potency 31,000-fold higher than that of Arg-Gly-Asp-Ser (RGDS). Flavostatin strongly inhibited high-shear-stress-induced platelet aggregation in platelet-rich plasma (PRP) with an IC50 value of 188 nM. Fluorescein isothiocyanate (FITC)-conjugated flavostatin saturably bound to unstimulated and ADP-stimulated washed platelets with high affinity (Kd values: 38 and 21 nM, respectively); the corresponding number of binding sites was 86460 and 79192 per platelet. In competition experiments with several glycoprotein IIb/IIIa antagonists, the binding of FITC-conjugated flavostatin to platelets was completely inhibited by ReoPro, triflavin, TP9201, MK383 and GR144053, but not by YM207, YM337 and B6A3.

Mortality rates for patients with a history of Kawasaki disease in Japan. Kawasaki Disease Follow-up Group

OBJECTIVE

To determine whether the mortality rate of patients with a history of Kawasaki disease is higher than that of the general population.

DESIGN

In a cohort study, 6585 patients with Kawasaki disease were observed from the first medical encounter because of the disease through the end of 1992, or until death. Standardized mortality ratios (SMRs) with 95% confidence intervals (CI) were calculated with vital statistics data of Japan for the control.

RESULTS

Of 6585 patients who met the eligibility criteria, 6550 (99.5%) were followed through either the end of the study or the date of death. Nineteen patients (14 male subjects) died during the study period; an overall SMR of 1.56 (955 CI, 0.94 to 2.43) was calculated for the entire study period. The SMR was 1.78 (95% CI, 0.97 to 2.99) for male subjects and 1.16 (95% CI, 0.38 to 2.71) for female subjects. During the acute phase of the disease (the first 2 months after onset), the SMR was higher, particularly in male subjects (SMR, 10.12; 95% CI, 3.72 to 22.07). After the acute phase, however, both boys and girls had low SMRs. Nine of the 19 deaths were caused by Kawasaki disease; there were 2 deaths as a result of congenital anomalies of the circulatory system and 2 subjects died of malignant neoplasms of lymphatic or hematopoietic tissues.

CONCLUSIONS

Although the mortality rate among those with a history of Kawasaki disease was elevated in Japan, many of the deaths that caused the elevation occurred during the acute phase of the disease. The mortality rate was not increased after the acute phase of the disease.

The coagulofibrinolytic state of patients with primary varicose veins of the lower legs

The relationship between a local hypercoagulable state and primary varicose veins of the lower legs was investigated by measuring the plasma levels of D-dimer (DD) and the thrombin-antithrombin-III complex (TAT) in 122 consecutive patients before treatment, and in 46 patients after surgical intervention and compression sclerotherapy. Elevated levels of DD and TAT were found in 25% and 20%, respectively, of the 122 patients, being significantly elevated in the patients with thrombophlebitis compared to the patients with no dermal symptoms, pigmentation, or stasis dermatitis. There was no significant difference in either parameter among eight groups of patients classified according to their valvular incompetence. The levels of DD and TAT were elevated before treatment in 25% and 20%, respectively, of 45 treated patients, but became significantly reduced after treatment. These results indicate that even though the local hypercoagulable state in varicose veins without thrombophlebitis is too subtle to be detected by systemic parameters such as DD and TAT, a local hypercoagulable state can be detected in a certain proportion of patients with venous stasis by these parameters.

Coordinated Regulation of the Genes Participating in Starch Biosynthesis by the Rice Floury-2 Locus

The recessive floury-2 (flo-2) locus of rice (Oryza sativa L.), which is located on chromosome 4, causes a strong reduction in expression of the gene encoding an isoform of branching enzyme RBE1 in immature seeds 10 d after flowering. Mapping of the RBE1 gene demonstrated the localization on rice chromosome 6, suggesting that the wild-type Floury-2 (Flo-2) gene regulates RBE1 gene expression in trans. However, reduced expression of the genes encoding some other starch-synthesizing enzymes, including another isoform of branching enzyme RBE3 and granule-bound starch synthase, was also found in the flo-2 seeds. In spite of the low level of RBE1 gene expression in the immature seeds of the flo-2 mutants, the RBE1 gene was equally expressed in the leaves of the wild type and flo-2 mutants. Thus, these results imply that the Flo-2 gene may co-regulate expression of some of the genes participating in starch synthesis possibly in a developing seed-specific manner.

Effects of acute and chronic ethanol administration on hepatic hemodynamics and hepatic oxygen consumption in awake rats

BACKGROUND/AIMS AND METHODS

We investigated the effects of acute and chronic ethanol administration on hepatic hemodynamics and hepatic oxygen delivery and consumption in awake rats, using the radiolabeled microsphere technique and measurement of oxygen content in blood.

RESULTS

Acute oral and intraarterial ethanol administration produced a significant increase in liver blood flow and hepatic oxygen delivery, but resulted in a significant (25-41%) decrease in hepatic oxygen consumption. These changes lasted up to 5 h after ethanol administration. At 24 h, hepatic oxygen consumption was significantly increased by 33% over control values. During withdrawal in rats fed liquid diets containing alcohol for 6 weeks, hepatic oxygen delivery was maintained at the same level as control pair-fed rats, while hepatic oxygen consumption increased by 28%. Further, in abstinent rats, acute ethanol readministration resulted in a 41% increase in hepatic oxygen delivery but a 32% decrease in hepatic oxygen consumption.

CONCLUSIONS

These findings demonstrate, in awake animals, a biphasic response of hepatic oxygen consumption following acute ethanol administration and an increase in hepatic oxygen consumption following chronic ethanol intake. Furthermore, acute ethanol treatment reduced hepatic oxygen consumption in spite of an increase in hepatic oxygen delivery.

Isolation and characterization of the rabbit cytochrome b5 gene

In mammals, two forms of cytochrome b5 (b5) are present and they are called according to their subcellar distribution as the microsomal-form and the soluble-form. These two forms of b5 s were encoded by separate mRNAs. In order to elucidate the mechanism of the expression of these two mRNAs, we isolated genomic clones that cover the gene for b5 from the rabbit genomic library. Analysis of these clones revealed that b5 gene spans over 20kbase pairs. A solube-form specific exon was found to be present between the two exons, which are in common to both forms of b5s. These observation demonstrate that the two forms of b5 mRNA are derived from the same gene by the alternative exon skip splicing.

In vivo evaluation of DX-9065a, a synthetic factor Xa inhibitor, in experimental vein graft

An in vivo effect of a novel synthetic Xa inhibitor, DX-9065a, was evaluated in a highly thrombogenic venous graft model. A woven Tetron tube graft was interposed in the inferior vena cava of rabbits. All the grafts were completely occluded within 5 hours after a bolus injection of heparin (50 U/kg) given just prior to the grafting. The following agents were continuously given to the respective group of rabbits for 2 h after the bolus injection of heparin; heparin (50 U/kg/h, UFH-group), DX-9065a (0.05 mg/kg/h, DX-group) and argatroban (32 microG/kg/h, MD-group). During a 5-h observation period, the anti-Xa activity in circulating blood between the UFH- and DX-group and the anti-thrombin activity between the UFH- and MD-group were not significantly different. The graft patency in the DX-group (4/4) and MD-group (4/4) was significantly better than that in the UFH-group (3/10). Ultrastructural analysis of the luminal surface of the harvested graft by scanning electron microscopy revealed the reduced formation of fibrin networks entrapping erythrocytes in the DX- and MD-group in comparison with the patent UFH-group. In conclusion, a novel synthetic Xa inhibitor DX-9065a exerts a potent in vivo antithrombotic effect, which was comparable with argatroban, a synthetic thrombin inhibitor.

Prevalence of impaired responsiveness to epinephrine in platelets among Japanese

The responsiveness of platelets only to epinephrine was markedly impaired in 23/140 (16%) healthy Japanese. The impaired responsiveness was not altered by changes in time and environment. Circulating level of catecholamines did not affect the responsiveness of platelets to epinephrine. A pilot family study indicated a possible familial nature of the defect. 3H methyl-yohimbine binding studies indicated that this defect was due to the decreased number of alpha 2 adrenergic receptor. Despite the defect, the potentiating effect of epinephrine on platelet aggregation stimulated by a low dose of ADP was normal. This abnormality is not apparently associated with any bleeding disorders and the clinical implication is unknown at present. It is, however, essential to acknowledge the prevalence of such defect in pursuing research on platelets stimulated by epinephrine.