High seropositivity of anti-CagA antibody in Helicobacter pylori-infected patients irrelevant to peptic ulcers and normal mucosa in Japan

CagA-positive H. pylori is reported to be associated with gastroduodenal disease in Western countries. To evaluate the relationship between CagA and disease, cloning of the entire cagA gene (3771 bp), insertion of a partial fragment (1272 bp) into an expression vector, purification of the recombinant protein, production of an antibody against the recombinant CagA protein through rabbits, and use of the recombinant CagA protein as an antigen, detection of the anti-CagA antibody by western blotting were all performed. Sera of 132 H. pylori-infected patients undergoing endoscopy were studied. Anti-CagA antibodies were detected in 90%, 87%, 90%, 94%, and 93% of patients with gastric ulcer (N = 34), duodenal ulcer (N = 27), chronic gastritis (N = 31), gastric cancer (N = 17), and normal mucosa (N = 15), respectively. High seropositivity of anti-CagA antibody even in individuals with normal mucosa indicated that CagA may not be a unique marker for disease by H. pylori infection in Japan.

The UNC-14 protein required for axonal elongation and guidance in Caenorhabditis elegans interacts with the serine/threonine kinase UNC-51

Certain unc mutants in the nematode Caenorhabditis elegans, such as unc-14 and unc-51, show abnormal axonal elongation and axonal structures. We cloned the unc-51 gene previously and predicted that it encodes a novel serine/threonine protein kinase. In this study, we precisely localized the activity to rescue an unc-14 mutation. Also, we identified four cDNA clones encoded by the unc-14 rescuing region, in screens for proteins that bind to UNC-51 using a yeast two-hybrid system. A mutation site in the cDNA was identified for each of the six unc-14 mutants, establishing that the unc-14 gene was cloned. The unc-14 gene encodes a novel protein of 665 amino acids, and is coexpressed with the unc-51 gene in the cell bodies and axons of almost all neurons including DD/VD and hermaphrodite-specific neurons. Another clone recovered in the two-hybrid screen encodes a carboxy-terminal region of UNC-51. Analysis using the yeast two-hybrid system suggested that a central region of UNC-14 bound to a carboxy-terminal region of UNC-51, and that the UNC-51 carboxy-terminal region oligomerized. In in vitro binding studies using recombinant fusion proteins, UNC-14 interacted with UNC-51 directly. We propose that UNC-51 protein kinase acts as an oligomer, and that UNC-14 is a regulator of UNC-51, in axonal elongation and guidance.

Expression of vascular endothelial growth factor at the human gastric ulcer margin and in cultured gastric fibroblasts: a new angiogenic factor for gastric ulcer healing

Angiogenesis plays a pivotal role in gastric ulcer repair. Several growth factors are involved in angiogenesis, and of these, vascular endothelial growth factor (VEGF) has received considerable attention, since it is the only factor that specifically acts on endothelial cells. However, the role of VEGF in gastric ulcer repair is not known. In the present study, we demonstrate the specific expression of VEGF at the gastric ulcer margin, using immunohistochemistry and RT-PCR. The specific receptors of VEGF, flt-1 and KDR were also detected in gastric mucosa. We further demonstrate the expression of VEGF by cultured human gastric fibroblasts which is enhanced by tumor necrosis factor-alpha. These data suggest that VEGF may play a role in angiogenesis in the process of gastric ulcer healing.

Identification of a novel gene cluster participating in menaquinone (vitamin K2) biosynthesis. Cloning and sequence determination of the 2-heptaprenyl-1,4-naphthoquinone methyltransferase gene of Bacillus stearothermophilus

We recently described the isolation and sequence analysis of a DNA region containing the genes of Bacillus stearothermophilus heptaprenyl diphosphate synthase, which catalyzes the synthesis of the prenyl side chain of menaquinone-7 of this bacterium. Sequence analyses revealed the presence of three open reading frames (ORFs), designated as ORF-1, ORF-2, and ORF-3, and the structural genes of the heptaprenyl diphosphate synthase were proved to consist of ORF-1 (heps-1) and ORF-3 (heps-2) (Koike-Takeshita, A., Koyama, T., Obata, S., and Ogura, K. (1995) J. Biol. Chem. 270, 18396-18400). The predicted amino acid sequence of ORF-2 (234 amino acids) contains a methyltransferase consensus sequence and shows a 22% identity with UbiG of Escherichia coli, which catalyzes S-adenosyl-L-methionine-dependent methylation of 2-octaprenyl-3-methyl-5-hydroxy-6-methoxy-1,4-benzoquinone. These pieces of information led us to identify the ORF-2 gene product. The cell-free homogenate of the transformant of E. coli with an expression vector of ORF-2 catalyzed the incorporation of S-adenosyl-L-methionine into menaquinone-8, indicating that ORF-2 encodes 2-heptaprenyl-1,4-naphthoquinone methyltransferase, which participates in the terminal step of the menaquinone biosynthesis. Thus it is concluded that the ORF-1, ORF-2, and ORF-3 genes, designated heps-1, menG, and heps-2, respectively, form another cluster involved in menaquinone biosynthesis in addition to the cluster of menB, menC, menD, and menE already identified in the Bacillus subtilis and E. coli chromosomes.

Lethal drug interactions of sorivudine, a new antiviral drug, with oral 5-fluorouracil prodrugs

Rats were orally co-administered sorivudine (SRV: 1-beta-D-arabinofuranosyl-(E)-5-(2-bromovinyl)uracil), a new oral antiviral drug for herpes zoster, with the oral anticancer drug tegafur (FT: 1-(2-tetrahydrofuryl)-5-fluorouracil as a prodrug of 5-fluorouracil (5-FU) once daily to investigate a toxicokinetic mechanism of 15 Japanese patients' deaths recently caused within a brief period by the drug interaction of these drugs. All the rats showed extremely elevated levels of 5-FU in plasma and tissues, including bone marrow and small intestine, and died within 10 days, whereas the animals given the same dose of SRV or FT alone were still alive over 20 days without any appreciable toxic symptom. Before their death, there was marked damage of bone marrow, marked atrophy of intestinal membrane mucosa, marked decreases in white blood cells and platelets, diarrhea with bloody flux, and severe anorexia as reported with the Japanese patients. Data obtained by in vivo and in vitro studies strongly suggested that (E)-5-(2-bromovinyl)uracil generated from SRV by gut flora was reduced in the presense of NADPH to a reactive form by hepatic dihydropyrimidine dehydrogenase (DPD), a key enzyme determining the tissue 5-FU levels, bound covalently to DPD as a suicide inhibitor, and markedly retarded the catabolism of 5-FU.

A partial deficiency of dehydrodolichol reduction is a cause of carbohydrate-deficient glycoprotein syndrome type I

Carbohydrate-deficient glycoprotein (CDG) syndrome type I is a congenital disorder that involves the underglycosylation of N-glycosylated glycoproteins (Yamashita, K., Ideo, H., Ohkura, T., Fukushima, K., Yuasa, I., Ohno, K., and Takeshita, K. (1993) J. Biol. Chem. 268, 5783-5789). In an effort to further elucidate the biochemical basis of CDG syndrome type I in our patients, we investigated the defect in the multi-step pathway for biosynthesis of lipid-linked oligosaccharides (LLO) by the metabolic labeling method using [3H]glucosamine, [3H]mannose, and [3H]mevalonate. The LLO levels in synchronized cultures of fibroblasts from these patients were severalfold lower than those in control fibroblasts in the S phase, and the oligosaccharides released from LLO showed the same structural composition, Glc1 approximately 3.Man9.GlcNAc.GlcNAc, in the case of both the patients and controls. The amount of [3H]mannose incorporated into mannose 6-phosphate, mannose 1-phosphate, and GDP-mannose was greater in fibroblasts from these patients than in the control fibroblasts in the G1 period, although the ratios of these acidic mannose derivatives as indicated by the relative levels of radioactivity were the same for the two types of fibroblasts. Furthermore, upon metabolic labeling with [3H]mevalonate, the level of [3H]dehydrodolichol in fibroblasts from these patients increased in the S phase, and the levels of [3H]dolichol and [3H]dolichol-PP oligosaccharides concomitantly decreased, although the chain length distribution of the respective dolichols and dehydrodolichols was the same in the two types of fibroblasts. These results indicate that the conversion of dehydrodolichol to dolichol is partially defective in our patients and that the resulting loss of dolichol leads directly to underglycosylation.

Lethal drug interactions of sorivudine, a new antiviral drug, with oral 5-fluorouracil prodrugs

Rats were orally co-administered sorivudine (SRV: 1-beta-D-arabinofuranosyl-(E)-5-(2-bromovinyl)uracil), a new oral antiviral drug for herpes zoster, with the oral anticancer drug tegafur (FT: 1-(2-tetrahydrofuryl)-5-fluorouracil) as a prodrug of 5-flourouracil (5-FU) once daily to investigate a toxicokinetic mechanism of 15 Japanese patients' deaths recently caused within a brief period by the drug interaction of these drugs. All the rats showed extremely elevated levels of 5-FU in plasma and tissues, including bone marrow and small intestine, and died within 10 days, whereas the animals given the same dose of SRV or FT alone were still alive over 20 days without any appreciable toxic symptom. Before their death, there was marked damage of bone marrow, marked atrophy of intestinal membrane mucosa, marked decreases in white blood cells and platelets, diarrhea with bloody flux, and severe anorexia as reported with the Japanese patients. Data obtained by in vivo and in vitro studies strongly suggested that (E)-5-(2-bromovinyl)uracil generated from SRV by gut flora was reduced in the presense of NADPH to a reactive form by hepatic dihydropyrimidine dehydrogenase (DPD), a key enzyme determining the tissue 5-FU levels, bound covalently to DPD as a suicide inhibitor, and markedly retarded the catabolism of 5-FU.

Two cistrons of the gerC operon of Bacillus subtilis encode the two subunits of heptaprenyl diphosphate synthase

The two proteins (GerC1 and GerC3) encoded by the gerC locus of Bacillus subtilis, which has been shown to be involved in vegetative cell growth and spore germination, were identified as dissociable heterodimers of the heptaprenyl diphosphate synthase involved in the biosynthesis of the side chain of menaquinone-7.

Bone mineral analysis in patients with biliary atresia after successful Kasai procedure

Metabolism is probably disturbed in patients with abnormal liver function who have undergone a successful Kasai procedure. We examined bone mineral metabolism in patients who have successfully undergone Kasai procedure. Bone mineral metabolism was examined in 8 patients with biliary atresia after a successful Kasai procedure. Five patients were female and 3 were male. The ages at Kasai procedure ranged from 50 to 80 days, and the follow-up periods ranged from 3 to 27 years after the operation. All patients eat a normal oral diet. We examined plasma levels of 25-OH-D3, 1, 25-(OH)2-D3, Ca and phosphorus (P). Bone mineral content of the lumbar spine (L2-L4) was assessed by dual energy x-ray absorptiometry (DEXA), and the data were expressed as a bone mineral density (BMD). Two patients showed abnormal levels on hepatic function tests. Plasma levels of 1, 25-(OH)2-D3, Ca, and P were normal in all patients. The level of 25-OH-D3 was normal in 7 patients. BMD levels were normal in 6 patients, but low in 2 who had undergone partial splenic embolization and splenectomy, respectively, due to hypersplenism. In long-term survivors of Kasai procedure, measurement of BMD may detect bone mineral deficiency earlier than measurements of serum levels of 25-OH-D, 1, 25-(OH)2-D, Ca and P.

A rapid, useful and quantitative method to measure telomerase activity by hybridization protection assay connected with a telomeric repeat amplification protocol

Telomerase, a ribonucleoprotein enzyme, is expected to be a new marker for cancer diagnosis. TRAP (the telomeric-repeat amplification protocol) developed by Kim et al. is a sensitive method to detect telomerase activity. Telomerase activity is detected by TRAP in most malignant cells in vivo and in vitro, but it is not found, or found only in very low amounts, in normal somatic cells and tissues. TRAP and its modified protocols are, however, not always suitable for measuring the activity of a large number of clinical samples to diagnose cancer, because they generally require a time-consuming detection step such as gel electrophoresis with radioactive materials. To improve the procedure for mass diagnosis, we applied a hybridization protection assay (HPA) to replace the detection step. HPA, which employs an acridinium-ester-labelled probe, is radioactivity-free, easy to handle without electrophoresis, quick, and applicable to a quantitative format. In this work we have established and demonstrated the advantages of TRAP/HPA. The telomerase activity of various primary and established cells, differentiating cancer cells, and normal and tumour colorectal and liver tissues was quantitatively analysed by TRAP/HPA. The results indicate that HPA combined with TRAP is a rapid and simple method, easy to handle and quantify, for the clinical diagnosis of cancer.

Ductoplasty for an aberrant hepatic duct in a choledochal cyst

The confluence of the right and left hepatic ducts at the hepatic hilum frequently shows normal anatomic variations. Choledochal cysts (CC) are also accompanied by similar variations, and devices for free drainage of bile are occasionally required in biliary reconstruction. We present a CC that had an aberrant posterior branch of the right hepatic duct draining into the distal common hepatic duct. A capacious hepaticoduodenostomy at the hilum was performed after joining the hilar and aberrant ducts.

Urinary reconstruction using appendix as a urinary and catheterizable conduit in 12 patients

BACKGROUND

The appendix vermiformis can provide an excellent urinary conduit or a catheterizable outlet in continent urinary reservoirs in selected cases. We report our clinical experience using the appendix in urinary reconstruction in adult patients.

METHODS

A total of 12 patients underwent urinary reconstruction using the appendix. The indications were pelvic malignancies except for 1 patient with neurogenic bladder and difficulty in self-catheterization via urethra. The appendix was used as a catheterizable conduit in 8 patients, and as a urinary conduit in 4 patients. The in situ submucosally embedded method was used in 6 patients and the Mitrofanoff method was used in 2 patients. Follow-up ranged from 3 to 41 months (mean, 22).

RESULTS

Early complications occurred in 3 patients (wound infection, false passage and intestinal anasotomotic leak). Late complications occurred in 3 (slight hydronephrosis, ileus, stomal stenosis). Emergent colostomy and pouchstomy with resection of the appendix was performed in the patient with anastomotic leak. The isoperistaltic Kock nipple valve was reconstructed for continence in this case. Prolonged ileus in 1 patient was treated by open surgery. Other complications were managed conservatively. End results were excellent in 8 patients, good in 3, and poor in 1.

CONCLUSIONS

The appendix can be used advantageously as an outlet of continent urinary reservoirs or for a urinary conduit when the ureter is too short to reach the skin. Complete continence and easy catheterization can be obtained, and the appendix construction can be used as a urinary conduit instead of the ileal conduit in poor risk patients.

Changes of hepatic volume after successful Kasai operation

The number of long term survivors who have undergone Kasai operation for biliary atresia is increasing, but some have a hepatic dysfunction likely to require liver transplantation in the near future. Hepatic volume possibly reflects whole liver function, and our objective was to assess the changes of hepatic volume after Kasai operation. Ten patients were studied. Ages ranged from 3 to 27 years. They underwent Kasai operation at ages ranging from 50 to 80 days. Liver areas (cm2) on CT images were measured with an image processing and analysis program (NIH Image 1.57). Hepatic volume (cm3) was calculated by summing up the areas of each image and multiplying by slice thickness (cm). After Kasai operation, the size of the liver increased to 1.7-1.9 times the standard volume, and then reduced to normal size around 5 years of age. In the teens, hepatic volume decreased below the standard volume. Segmental hypertrophy accompanying atrophy of other hepatic segments was observed in 9 out of 10 patients; right lobe hypertrophy: 6, medial segment: 2, and lateral segment: 1. Therefore, progressive hepatic atrophy begins in the teens, but is compensated for by segmental hypertrophy.

Polyprenyl diphosphate synthases

It is noteworthy that in spite of the similarity of the reactions catalyzed by these prenyltransferases, the modes of expression of catalytic function are surprisingly different, varying according to the chain length and stereochemistry of reaction products. These enzymes are summarized and classified into four groups, as shown in Figure 13. Short-chain prenyl diphosphates synthases such as FPP and GGPP synthases require no cofactor except divalent metal ions, Mg2+ or Mn2+, which are commonly required by all prenyl diphosphate synthases. Medium-chain prenyl diphosphate synthases, including the enzymes for the synthesis of all-E-HexPP and all-E-HepPP, are unusual because they each consist of two dissociable dissimilar protein components, neither of which has catalytic activity. The enzymes for the synthesis of long-chain all-E-prenyl diphosphates, including octaprenyl (C40), nonaprenyl-(C45), and decaprenyl (C50) diphosphates, require polyprenyl carrier proteins that remove polyprenyl products from the active sites of the enzymes to maintain efficient turnovers of catalysis. The enzymes responsible for Z-chain elongation include Z,E-nonaprenyl-(C45) and Z,E-undecaprenyl (C55) diphosphate synthases, which require a phospholipid. The classification of mammalian synthases seems to be fundamentally similar to that of bacterial synthases except that no medium-chain prenyl diphosphate synthases are included. The Z-prenyl diphosphate synthase in mammalian cells is dehydrodolichyl PP synthase, which catalyzes much longer chain elongations than do bacterial enzymes. Dehydrodolichyl PP synthase will be a major target of future studies in this field in view of its involvement in glycoprotein biosynthesis.

An improved double-tuned and isotope-filtered pulse scheme based on a pulsed field gradient and a wide-band inversion shaped pulse

We have developed an improved isotope-filtered pulse scheme in combination with a double-tuned filter, a hyperbolic secant inversion pulse, and a z-filter with a pulsed field gradient. These filtering pulse schemes have been incorporated into several one-, two-, and three-dimensional experiments, which were applied to the (13)C/(15)N uniformly labeled N-terminal SH3 domain of Grb2 complexed with the unlabeled Sos-derived peptide. The proton resonances of the Sos-derived peptide were unambiguously assigned using isotope-filtered DQF-COSY, TOCSY and NOESY spectra. Furthermore, in the isotope-filtered, isotope-edited 3D NOESY spectrum, intermolecular NOEs between the labeled protein and the unlabeled peptide could be identified. Through these applications, we demonstrate the high filtering efficiency of the presented pulse scheme.

[A case of Fournier's gangrene with healing accelerated by argatroban]

A 58-year-old man was admitted to our hospital complaining of pain and marked swelling of scrotum and perineum. Physical and radiological examinations revealed gas-producing gangrenous changes involving the scrotum. Debridement was urgently carried out. Following the debridement under control of diabetes mellitus, antimicrobial agents and argatroban, a newly synthesized antithrombin medicine, were administered. Argatroban was used for the purpose of improving vascular insufficiency. Healthy granulation tissue was present five weeks later. Then surgical closure was carried out. Computed tomography was useful to make early diagnosis, and argatroban was thought to accelerate healing of the gangrene.

Keratinocyte growth factor is an endogenous stimulant of rabbit gastric epithelial cell proliferation and migration in primary culture

Mesenchymal-epithelial interactions are important in the gastric mucosal repair. However, specific factors responsible for such interactions have not been established. In the present study, keratinocyte growth factor (KGF) significantly stimulated proliferation of gastric epithelial cells dose dependently and synergistically with hepatocyte growth factor (HGF), epidermal growth factor (EGF) and insulin. Restitution of gastric epithelial monolayers was also assessed, using a round wound restitution model. Keratinocyte growth factor facilitated the restitution of gastric epithelial cells significantly but did not have any effects on gastric fibroblasts. Keratinocyte growth factor receptor mRNA was expressed by gastric epithelial cells, indicating that these effects were elicited by the specific receptor mediated pathway. Northern blot analysis revealed the expression of KGF mRNA in gastric fibroblasts but not in gastric epithelial cells, indicating the production of KGF. These results suggest that KGF might be involved in gastric mucosal repair, through mesenchymal-epithelial interaction.

Measurement of LET distribution and dose equivalent on board the space shuttle STS-65

Space radiation dosimetry measurements have been made on board the Space Shuttle STS-65 in the Second International Microgravity Laboratory (IML-2). In these measurements, three kinds of detectors were used; one is a newly developed active detector telescope called "Real-time Radiation Monitoring Device (RRMD)" utilizing silicon semi-conductor detectors and others are conventional detectors of thermoluminescence dosimeters (TLDs) and CR-39 plastic track detectors. Using the RRMD detector, the first attempt of real-time monitoring of space radiation has been achieved successfully for a continuous period of 251.3 h, giving the temporal variations of LET distribution, particle count rates, and rates of absorbed dose and dose equivalent. The RRMD results indicate that a clear enhancement of the number of trapped particles is seen at the South Atlantic Anomaly (SAA) without clear enhancement of dose equivalent, while some daily periodic enhancements of dose equivalent due to high LET particles are seen at the lower geomagnetic cutoff regions for galactic cosmic ray particles (GCRs). Therefore, the main contribution to dose equivalent is seen to be due to GCRs in this low altitude mission (300 km). Also, the dose equivalent rates obtained by TLDs and CR-39 ranged from 146.9 to 165.2 microSv/day and the average quality factors from 1.45 to 1.57 depending on the locations and directions of detectors inside the Space-lab at this highly protected orbit for space radiation with a small inclination (28.5 degrees) and a low altitude (300 km). The LET distributions obtained by two different detectors, RRMD and CR-39, are in good agreement in the region of 15-200 keV/mm and difference of these distributions in the regions of LET < 15 keV/mm and LET > 200 keV/mm can be explained by considering characteristics of CR-39 etched track formation especially for the low LET tracks.

Gestational changes of glucose transporter gene expression in the mouse placenta and decidua

Glucose is required for fetal development and energy metabolism. The glucose transfer from maternal circulation to fetus, in which glucose transporter (GLUT) should play an important role, is fundamental in the utero-placental-fetal system. In this study, the gestational changes of GLUT1 and GLUT3 mRNA level in the mouse placenta and decidua were analyzed by Northern blot analysis. The levels of GLUT1 mRNA in the mouse placenta and decidua increased as gestational day proceeded. Although the level of GLUT3 mRNA in the decidua slightly decreased as pregnancy proceeded, there was a switch in size of a major band of GLUT3 from 4.1 kb to 2.7 kb in the mouse placenta detected by Northern blot analysis. These findings suggest the presence of a difference in the gestational modulation of the level of GLUT1 and GLUT3 in the uteroplacental system.

Pyogenic vertebral osteomyelitis after acute bacterial prostatitis: a case report

A case of pyogenic vertebral osteomyelitis after acute bacterial prostatitis in a 78-year-old man is reported. The rarity and subtle clinical presentation of this condition, and the delayed appearance of radiologic signs of progression to destructive osteomyelitis, contributed to a significant delay in diagnosis. An arterial blood culture positive for bacterial growth during the episode of acute prostatitis suggested that bacteremia might result from hematogenous spread of the infection to the vertebral column via the venous system. Since intensive antimicrobial therapy proved ineffective, debridement of the first and second lumbar vertebral bodies, and anterior spinal fusion from the twelfth thoracic to the third lumbar vertebrae were performed. The patient's high fever and severe lumbago subsided immediately after the surgery. The possibility of development to pyogenic vertebral osteomyelitis should be kept in mind when treating a serious genitourinary tract infection.

Cloning and expression of cDNA for O-acetylation of GD3 ganglioside

O-acetylated sialic acids of glycoproteins and gangliosides show cell type-specific and developmentally regulated expression in various systems and sometimes reappear as oncofetal antigens. O-acetylation of sialic acids may influence cell-cell interactions mediated by the sialic acid-binding lectins. Here we describe the molecular cloning and sequencing of a gene that produces O-acetyl disialoganglioside (O-acetyl GD3). Expression analysis showed that this gene product participates the O-acetylation of GD3 ganglioside sialic acid. The deduced amino acid sequence of the product was found to be similar to the milk fat globule membrane glycoprotein.

[Adherent reaction among activated platelets, polymorphonuclear cells and vascular endothelial cells under thrombin stimulation or shear stress]

Platelet activation in addition to blood coagulation abnormality is regarded as a primary factor of thrombosis by atherosclerotic obstruction. Therefore, the platelet activation on atherosclerosis is considered to correlate with shear stress generated between blood cells and endothelial cells in blood flow. P-selectin on the surface of the platelet membrane is measured by flowcytometry as a marker of platelet activation. Herein, we examined the phenomena of platelet activation and adherent platelets with leukocytes (ad-P.L) on stored platelet concentration (PC) and chronic rheumatoid arthritis (RA), moreover, of the adherent platelets or polymorphonuclear cells (PMN) with endothelial cells (EC) in shear stress by using an apparatus we devised. The rate of platelet activation and ad-P.L increased in PC with storage, and the sensitivity of platelets to thrombin decreased. The rate of platelet activation and ad-P.L increased in RA in vivo. Many adherent platelets with EC were found at a low shear rate on normal EC but at a high shear rate on denatured EC without any specific adherent property. Adherent PMN with EC had several hundred times more denatured EC than normal EC and the relationship with shear rate disappeared on denatured EC. The platelet activation and relationship between platelets or leukocytes and EC as to the cause of thrombosis are important subjects for future studies.

hiiragi, a gene essential for wing development in Drosophila melanogaster, affects the Notch cascade

A recessive mutation, hiiragiP1, on the second chromosome of Drosophila was obtained by P element insertion mutagenesis. Flies homozygous for hiiragiP1 have notched wing margins. Genetic interactions between hiiragi and the genes that encode components of Notch signaling, such as Notch, Hairless, Serrate and deltex, strongly support the involvement of hiiragi in the signal transduction cascade of Notch. It has been reported that Serrate and Delta, other components of Notch signaling, share EGF-like repeats and a second conserved cysteine-rich motif, and that these components interact physically with the same region of Notch. In hiiragiP1; SerrateD/+ double mutants, we observed synergistic enhancement of the notched phenotype of wing margins. In contrast, Delta FX3 had no phenotypic effect on hiiragiP1 in hiiragiP1; Delta FX3/+ double mutants. Taken together, these results indicate that hiiragi is involved in the Notch signaling cascade induced by Serrate rather than by Delta.