Molecular cloning and sequencing of two phospho-beta-galactosidase I and II genes of Lactobacillus gasseri JCM1031 isolated from human intestine

Lactobacillus (Lb.) gasseri JCM1031, which is classified into the B1 subgroup of the Lb. acidophilus group of lactic acid bacteria, characteristically produces two different phospho-beta-galactosidases (P-beta-gal) I and II in the same cytosol as reported in our previous papers [Biosci. Biotech. Biochem., 60, 139-141, 708-710 (1996)]. To clarify the functional and genetic properties of the two enzymes, the structural genes of P-beta-gal I and II were cloned and sequenced. The structural gene of P-beta-gal I had 1,446 bp, encoding a polypeptide of 482 amino acid residues. The structural gene of P-beta-gal II had 1,473 bp, encoding a polypeptide of 491 amino acid residues. The deduced relative molecular masses of 55,188 and 56,243 agreed well with the previous value obtained from the purified P-beta-gal I and II protein, respectively. Multiple alignment of the protein sequence of P-beta-gal I and II with those of P-beta-gals from 5 microorganisms had 30-35% identity on the amino acid level, but those with phospho-beta-glucosidases from 5 microorganisms had the relatively high identity of about 50%. Considering that this strain grows on lactose medium and shows no beta-galactosidase activity, and that purified P-beta-gal I and II can obviously hydrolyze o-nitrophenyl-beta-D-galactopyranoside 6-phosphate (substrate), and also the conservation of a cysteine residue in the molecule, the P-beta-gal I and II were each confirmed as a novel P-beta-gal enzyme.

Sonographic findings of malignant fibrous histiocytoma of the mesentery-report of two cases

We present two cases of malignant fibrous histiocytoma (MFH) of the mesentery. A whorled internal structure observed on sonogram and large feeding and draining vessels demonstrated on color Doppler sonogram in these cases were worth noticing. When sonography reveals an abdominal tumor with such findings, although very rare, the possibility of a MFH of the mesentery must be considered. We also review briefly the literature.

Color Doppler findings in Castleman's disease of the mesentery

Castleman's disease is a relatively rare lymphoproliferative disease. We report an asymptomatic case of Castleman's disease isolated to the mesentery and detected incidentally by sonography. In this case, color Doppler sonography demonstrated an artery penetrating the mass's hilum, suggesting a lymphatic origin of the lesion, as well as fine accessory peripheral arteries, suggesting malignancy. To our knowledge, there has been no previous report of detailed color Doppler findings in Castleman's disease.

Sonographic and color Doppler findings of rupture of liver tumors

We present six cases of ruptured liver tumor (hepatocellular carcinoma, five cases; liver metastasis, one case) in which gray-scale sonography revealed an ascites containing constantly moving dense high-echo spots, leading to a high suspicion of acutely developing hemoperitoneum. Color Doppler sonography helped in detecting the rupture site by demonstrating a high-velocity jet flow from it. Although four of six patients were dead within 3 months, detection of the rupture site by color Doppler sonography made the initial transarterial embolization therapy easy and prompt.

Splenic artery aneurysm: value of color Doppler and the limitation of gray-scale ultrasonography

BACKGROUND

To reevaluate the advantages and limitations of gray-scale and color Doppler sonography in the diagnosis of splenic artery (Sp-A) aneurysm.

METHODS

We reviewed the gray-scale and color Doppler sonograms of five cases with Sp-A aneurysm (four patients with portal hypertension and one patient without portal hypertension). Color Doppler sonography was performed in all five patients, and power Doppler sonography was performed in three.

RESULTS

Gray-scale sonography failed to detect the aneurysm in four of five cases because of a surrounding splenorenal (Sp-R) shunt in three patients and marked calcification of the aneurysmal wall in one patient. Pulsed Doppler sonography showed a slightly turbulent pulsatile flow along the aneurysmal wall, which immediately led to the diagnosis in four cases, including the three cases with Sp-R shunt. In one case, color Doppler sonography failed to detect the aneurysm because of a markedly calcified aneurysmal wall, although power Doppler sonography could visualize the aneurysm.

CONCLUSIONS

Gray-scale sonography is not a useful diagnostic tool for Sp-A aneurysm. Clinicians should use color Doppler sonography in the evaluation of the splenic hilus in patients with Sp-R shunt to find a small Sp-A aneurysm. The addition of power Doppler sonography is helpful in visualizing calcified Sp-A aneurysms.

Transport of temocaprilat into rat hepatocytes: role of organic anion transporting polypeptide

The mechanism for hepatic uptake of temocaprilat, an angiotensin-converting enzyme inhibitor that is predominantly excreted into bile was studied using isolated rat hepatocytes and COS-7 cells expressing the organic anion transporting polypeptide (oatp1). The uptake of temocaprilat into isolated rat hepatocytes exhibited saturation with a Km of 20.9 microM and a Vmax of 0.21 nmol/min/mg protein. This uptake was temperature sensitive and was significantly reduced by metabolic inhibitors, a sulfhydryl-modifying reagent and an anion-exchange inhibitor, although the replacement of Na+ with Li+ in the medium did not affect the uptake. [3H]Temocaprilat uptake was inhibited by estradiol-17beta-D-glucuronide and dibromosulphophthalein, typical substrates for the Na+-independent organic anion transporter, in a concentration-dependent manner, whereas excess estradiol-17beta-D-glucuronide did not completely inhibit the uptake. Temocaprilat uptake into COS-7 cells transfected with oatp1 cDNA revealed a concentration-dependency with a Km of 46.7 microM, a value comparable with that obtained in isolated hepatocytes. The contribution of oatp1 to carrier-mediated hepatic uptake of temocaprilat was less than 50% by correcting the uptake clearance with that of estradiol-17beta-D-glucuronide. A good linear correlation was observed for the inhibitory effect of angiotensin-converting enzyme inhibitors (benazeprilat, cilazaprilat, delaprilat and enalaprilat) between isolated hepatocytes and oatp1-expressing cells. These data suggest that oatp1, along with another transporter(s), mediates the uptake of angiotensin-converting enzyme inhibitors into rat hepatocytes.

Isolation and structure of pompilidotoxins, novel peptide neurotoxins in solitary wasp venoms

Novel peptide neurotoxins, alpha- and beta-pompilidotoxins (alpha- and beta-PMTXs), were purified from the venoms of the solitary wasps Anoplius samariensis and Batozonellus maculifrons. Their structures were analyzed mostly by MALDI-TOF-MS, which were corroborated by solid-phase synthesis. alpha-PMTX, with 13 amino acid residues and the sequence of Arg-Ile-Lys-Ile-Gly-Leu-Phe-Gln-Asp-Leu-Ser-Lys-Leu-NH2, greatly potentiates synaptic transmission of lobster leg muscle by the presynaptic mechanisms. beta-PMTX, in which the lysine residue at 12 position of alpha-PMTX was replaced with arginine, was more potent than alpha-PMTX.

Sonographic and color Doppler findings of gastrointestinal myogenic tumors with a marked extraluminal growth

We present five cases with gastro (four cases) and intestinal (one case) myogenic tumors with a marked extraluminal growth. In all cases, incidental discovery of an asymptomatic mass prompted further examination. One of three cases with a pedunculated growth mimicked a gallbladder cancer. The mass of a jejunal leiomyoma case changed markedly in location under probe compression. Color Doppler sonography confirmed not only the hypervascular nature of the mass but also feeding and draining vessels.

Portal vein thrombosis associated with antiphospholipid syndrome: a case report

We present a case of portal vein thrombosis associated with antiphospholipid syndrome (APS). The patient had an end-stage renal disease and underwent hemodialysis, and a portal thrombus was incidentally found in the main portal vein by color Doppler sonography. The patient is followed up now with long-term anticoagulant therapy. This experience suggests that color Doppler sonography be performed for patients with APS to improve their management.

Novel anti-respiratory syncytial(RS) viral compounds: benzodithiin derivatives

Benzodithiin derivatives are highly potent and specific inhibitors of respiratory syncytial virus (RSV) replication in vitro. The most potent and selective congener of a benzodithiin derivative is 1,4-dihydro-2,3-benzodithiin(RD3-0028). According to the modified 3-(4,5-dimethylthiazole-2-yl) 2,5-diphenyl tetrazolium bromide (MTT) assay developed in our laboratories, this compound has a 50% effective concentration of 4.5 microM and a 50% cytotoxic concentration of 271.0 microM, which is superior to that of ribavirin. This compound also inhibits RSV strain subgroups A and B and clinical isolates. RD3-0028, however, does not inhibit the replication of influenza A virus, measles virus, herpes simplex virus types 1 and 2, or human cytomegalovirus. Two other benzodithiin derivatives [1,4-dihydro-6-methyl-2,3-benzodithiin (RD3-0270) and 1,4-dihydro-5-methyl-1-2,3-benzodithiin (RD3-0284)] also inhibit RSV replication at a selectivity index greater a factor of 20. These results suggest that the benzodithiin skeleton is an important structure for inhibitory activity against RSV replication.

Synthesis and biological activity of 2-methyl-20-epi analogues of 1 alpha,25-dihydroxyvitamin D3

Synthesis and biological evaluation of all eight possible A-ring diastereomers of 2-methyl-20-epi-1,25-dihydroxyvitamin D3 are described. Among the analogues synthesized. 2 alpha-methyl-20-epi-1 alpha,25-dihydroxyvitamin D3 exhibited exceptionally high potency. The double modification of 2-methyl substitution and 20-epimerization yielded analogues with unique activity profiles.

Effects of alpha-pompilidotoxin on synchronized firing in networks of rat cortical neurons

We studied the effect of a novel neurotoxin, alpha-pompilidotoxin (alpha-PMTX) on the spontaneously synchronized network firing of cultured rat cortical neurons. Alpha-PMTX acted immediately and irreversibly to disrupt synchronous activity, leaving only residual sparse, uncorrelated firing and was effective at concentrations of 10 nM. In the presence of bicuculline to block inhibitory synaptic transmission, the shutdown in synchronized activity occurred with a significant delay, required a higher concentration of alpha-PMTX (> 100 nM), and was preceded by a transiently increased level of firing. It appears that both inhibitory and excitatory neuronal activity or synaptic transmission are amplified by alpha-PMTX, but that intense activity eventually leads to inactivation or transmitter depletion.

Anterior abdominal wall pathologies detected by high-frequency annular array

AIM AND METHODS

In 1850 patients, high-frequency (HF: 7.5-10 MHz) annular array US examination was performed to evaluate the value of HF annular US in the detection of pathologies of the anterior abdominal wall.

RESULTS

HF annular US revealed pathological lesions (metastasis, benign tumor, lymphoma, hematoma, fistula, hernia, abscess) in 37 patients. The lesions were detected by conventional medium-frequency (3.5-3.75 MHz) US in only 8 of 37 cases (21.6%). HF annular US added information that altered clinical management in 19 cases (51.4%), predominantly in cases with tumors and fistulas.

CONCLUSION

The addition of HF annular US to a conventional US examination increases the detectability of small, but clinically important pathologies in the anterior abdominal wall.

Purification and characterization of NADH-dependent glutamate synthase from the silkworm fat body (Bombyx mori)

NADH-dependent glutamate synthase (Nadh-Gogat; EC 1.41.14) was purified 766-fold from the fat body of 5th instar larvae of the silkworm with a final specific activity of 13.8 units/mg protein by a produce including ammonium sulfate fraction, Q-Sepharose HP ion exchange column chromatography, Blue Sepharose FF affinity column chromatography and Superdex 200 HR gel filtration. The purified enzyme yielded a single band corresponding to a molecular mass of 195kDa by SDS-polyacrylamide gel electrophoresis. Molecular mass of the native enzyme was estimated to be 190 kDa by Superdex 200HR gel filtration, suggesting that the enzyme is composed of a monomeric polypeptide. The enzyme showed an absorption spectrum with maximum values at 272, 375, and 435 nm, suggesting the presence of a flavin prosthetic group in the enzyme. The N-terminal amino acid sequence showed a high similarity to those of other GOGATs from plants, yeast and bacteria, but no similarity to other known proteins was detected. The enzyme exhibited a strong specificity to the electron donor and substrates; NADH as electron donor, 2-oxoglutarate as amino acceptor and glutamine as amino donor were essential for the catalytic activity. The optimum pH was around 7.5, at which Km values for 2-oxoglutarate, glutamine and NADH were 17, 220 and 5.7 micro M, respectively. Azaserine, 6-diazo-5-oxonorleucine and p-chloromercuribenzoic acid were strong inhibitors of the activity. These result show that NADH-GOGAT in the silkworm fat body strongly resembles other eukaryotic NADH-GOGATs, suggesting that it plays a significant role in ammonia assimilation in the same manner as the other enzymes.

Small bowel varices: report of two cases

Two cases of small bowel (S-B) varices associated with portal hypertension, one with liver cirrhosis and one with portal thrombus, are reported. Detection of S-B varices has been a challenging task and several invasive diagnostic techniques have been used for this purpose. However, in our cases, color Doppler sonography revealed the S-B varices supplied by the superior mesenteric vein and draining to the iliac (one case) or ovarian vein (other case), which helped to establish an early appropriate diagnostic and treatment plan.

RD6-2198, a novel betain-type fluoroalkylated oligomer, inhibits the replications of human immunodeficiency virus type 1 and other enveloped viruses

We have examined a novel betain-type fluoroalkylated oligomer, RD6-2198, for its inhibitory effects on the replication of human immunodeficiency virus type 1 (HIV-1) and other enveloped viruses, including herpes simplex virus types 1 and 2 (HSV-1 and HSV-2, respectively) and respiratory syncytial virus (RSV) in cell cultures. We have found that the compound is a potent and selective inhibitor of these viruses. RD6-2198 inhibited the replication of HIV-1IIIB at a concentration of 0.85 microg/ml with a selectivity index greater than 59 in MT-4 cells. Furthermore, its 50% effective concentration (EC50) values for HSV-1, HSV-2 and RSV, were 0.51, 0.94 and 3.0 microg/ml, respectively. We found that the RD6-2198 suppressed the gp120-CD4 interaction (as monitored by an enzyme-linked immunosorbent assay (ELISA) method). RD6-2198 also inhibited the binding of anti-gp120 monoclonal antibody to gp120 expressed on MOLT-4/IIIB cells (MOLT-4 cells chronically infected with HIV-1IIIB). However, the compound did not inhibit the interaction of anti-CD4 antibody with CD4. These results suggest that RD6-2198 interacts with the viral envelope glycoprotein and thereby inhibits the viral adsorption process. In addition, RD6-2198 was also found to suppress the proliferation of MOLT-4/IIIB cells. When applied topically, RD6-2198 at a concentration of 10 mg/ml completely protected mice from an intravaginal HSV-2 infection.

Inhibitory effects of podophyllotoxin derivatives on herpes simplex virus replication

Podophyllotoxin and its derivatives were examined for inhibitory effects on the replication of herpes simplex virus types 1 and 2 (HSV-1 and HSV-2), including acyclovir-resistant virus and clinical isolates. Deoxypodophyllotoxin (RD4-6266) proved to be a highly potent and selective inhibitor of all HSV strains in MRC-5 cells. EC50 values of RD4-6283 (in which the methylenedioxy ring A is modified) for HSV-1 and -2 were inferior to those of deoxypodophyllotoxin. However, podorhizol (RD4-6277) and 5'-methoxy-podorhizol (RD4-6276), in which ring C is absent, did not inhibit HSV replication. Moreover, RD4-6266 also inhibited the production of infectious virus particles of HSV-1 KOS strain and HSV-2 G strain. In contrast, none of the podophyllotoxin derivatives were found to have an antiviral effect against influenza A virus, respiratory syncytial virus or human cytomegalovirus in doses not toxic to the cells.

Inhibition of human cytomegalovirus proteinase by salcomine derivatives

Salcomine, N,N'-bis(salicylidene)ethylene diamino-cobalt (II), and its derivatives were evaluated for their ability to inhibit selectively human cytomegalovirus (HCMV) proteinase activity. The 50% inhibitory concentration (IC50) of salcomine was 1.4 microM for HCMV proteinase, but > 200 microM for three other serine proteinases (trypsin, > 250 microM; chymotrypsin, 206 microM; and elastase, > 250 microM). Two salcomine derivatives also inhibited HCMV proteinase with IC50 values under 2 microM. Studies of the structure-activity relationship of salcomine-related compounds showed that the phenyl moiety and the spacer moiety (distance between the two amines) were instrumental in the inhibition of HCMV proteinase. Moreover, salcomine inhibited the growth of laboratory strain AD169 and three clinical isolates at a 50% effective concentration (EC50) range of 1.92-2.89 microM. These results show that salcomine derivatives are potent and selective inhibitors of HCMV proteinase and HCMV replication in cell culture. Salcomine derivatives appear to be worth pursuing as candidate drugs for the chemotherapy of HCMV infection.

Intrahepatic venous collaterals

BACKGROUND

The aim of this study was to reevaluate the causes and sites of intrahepatic venous collaterals and to determine the role of color Doppler sonography in the diagnosis of this relatively rare vascular abnormality.

METHODS

Real-time color Doppler sonography was used to study 21 patients with intrahepatic venous collaterals. The cause, distribution, and clinical manifestations of collaterals were determined, and Doppler waveforms obtained from the collaterals were also analyzed.

RESULTS

First, the causes of intrahepatic venous collaterals were divided roughly into two groups according to the presence or absence of veno-occlusions. The former group included liver tumors (six cases), primary Budd-Chiari syndrome (five cases), and metastatic adrenal tumors invading the inferior vena cava (two cases). The latter group consisted of diaphragmatic hernia (three cases), Osler-Weber-Rendu disease (two cases), and congestive liver (one case). The cause was not determined in two cases. Second, venous collaterals were distributed throughout the entire liver in primary Budd-Chiari syndrome but localized in the other cases. Third, Doppler waveforms of the collaterals were divided into two patterns: flat flow and multiphasic flow. Flat flow pattern was seen in patients with veno-occlusive diseases, and multiphasic flow pattern was seen in patients without veno-occlusive disease.

CONCLUSION

The relationship between intrahepatic venous collaterals and veno-occlusive diseases has been emphasized in the literature, but the results of our series showed that they occurred under a wide variety of conditions, even without veno-occlusive diseases, including diaphragmatic hernia and Osler-Weber-Rendu disease. The analysis of the Doppler waveforms of the collaterals was useful in differentiating those due to veno-occlusive diseases and those not.

Lobar atrophy of the liver

Lobar atrophy of the liver due to causes other than liver tumor or liver cirrhosis is a relatively rare pathological condition, and there are only a few reports in the literature. We report six such cases and try to evaluate the relationship between lobar atrophy and portal flow disturbance. The patients could be divided into two groups according to the site of the atrophy: those with atrophy of the left lobe (two cases) and those with atrophy of the right lobe (four cases). The two cases with atrophy of the right lobe had hepatholithiasis in the involved segments, but the cause was not determined in the remaining four cases. In all six cases, portal flow disturbance was noted, including invisibility of the portal vein in four cases, narrowing in one case, and portal thrombus in one case. Collateral circulation was not recognized in any of our cases. Of interest is the mode of lobar atrophy. Atrophy of the right lobe was always associated with marked enlargement of the left lobe, but that of the left lobe did not induce an enlargement of the right lobe.

Role of nerve growth factor in cutaneous wound healing: accelerating effects in normal and healing-impaired diabetic mice

Four full-thickness skin wounds made in normal mice led to the significant increase in levels of nerve growth factor (NGF) in sera and in wounded skin tissues. Since sialoadenectomy before the wounds inhibited the rise in serum levels of NGF, the NGF may be released from the salivary gland into the blood stream after the wounds. In contrast, the fact that messenger RNA and protein of NGF were detected in newly formed epithelial cells at the edge of the wound and fibroblasts consistent with the granulation tissue produced in the wound space, suggests that NGF was also produced at the wounded skin site. Topical application of NGF into the wounds accelerated the rate of wound healing in normal mice and in healing-impaired diabetic KK/Ta mice. This clinical effect of NGF was evaluated by histological examination; the increases in the degree of reepithelialization, the thickness of the granulation tissue, and the density of extracellular matrix were observed. NGF also increased the breaking strength of healing linear wounds in normal and diabetic mice. These findings suggested that NGF immediately and constitutively released in response to cutaneous injury may contribute to wound healing through broader biological activities, and NGF improved the diabetic impaired response of wound healing.

[Pilot study of relapsed osteosarcoma and brain tumor with ifosfamide, carboplatin and etoposide (ICE therapy)]

Ifosfamide, Carboplatin and Etoposide (ICE) therapy was used to treat 4 patients, 2 with refractory osteosarcoma, and one each with relapsed brain tumor and newly diagnosed brain tumor. ICE therapy was administered in doses of Ifosfamide 1,800 mg/m2 x 5, Carboplatin 400 mg/m2 x 2 and Etoposide 100 mg/m2 x 5. A total of 30 courses were administered. Two cases of osteosarcoma had a stable disease (range, 3-9 months) and 2 cases of brain tumor had a complete response by magnetic resonance imaging. Moderate or severe toxicity evaluated on a per course basis included: neutropenia 83%, thrombocytopenia 93%, fever 30%, hepatotoxicity 3%, and hemorrhagic cystitis 3%. The median time to hematologic recovery was 20 days. ICE therapy is highly effective for the treatment of refractory or recurrent solid tumors with acceptable toxicity.

A novel and practical route to A-ring enyne synthon for 1 alpha,25-dihydroxyvitamin D3 analogs: synthesis of A-ring diastereomers of 1 alpha,25-dihydroxyvitamin D2 and 3-methyl-1,25-dihydroxyvitamin D3

A novel and practical route to the A-ring enyne synthon (2), which can be versatile for a variety of A-ring analogs of 1 alpha,25-dihydroxyvitamin D3 (1), was developed. This novel method led to an improved synthesis of the A-ring diastereomers of 1, the compounds 13-15, and synthesis of the new analogs, 2-methyl-1,25-dihydroxyvitamin D3 (4) with its all possible diastereomers. The biological evaluation of the 2-methyl analogs showed the alpha alpha beta-isomer to be more potent than 1.

Sonographic findings of anomalous position of the gallbladder

Anomalous position of the gallbladder is relatively rare and has been reported only in isolated case reports. We tried to determine its ultrasound (US) findings on the basis of 18 such patients. In the left-side gallbladder group (nine patients), the gallbladder was imaged as an oval cystic mass in front of the pancreas. In all patients, the narrow neck of the gallbladder was clearly detected by US in the usual location before the main portal vein. Four of nine patients had small gallbladder stones. The retrohepatic gallbladder group (four patients) showed marked atrophy of the right lobe of the liver. Two patients had multiple gallstones in the bile ducts of the right lobe. All patients in the suprahepatic retrohepatic gallbladder group (four patients) were cirrhotic, and the anterior segment of the right lobe was markedly atrophied. In the intercostal scan, the gallbladder mimicked a perihepatic fluid. In the floating gallbladder group (one patient), the gallbladder was imaged as a cystic mass in the anterior abdominal wall. Surgical intervention showed a severely inflamed gallbladder, with small stones adhered into the anterior abdominal wall and partially ruptured. Knowledge of the wide range of US findings of malposition of the gallbladder helps in avoiding misdiagnosis.

Color Doppler findings of gastrointestinal varices

BACKGROUND

Compared with esophageal varices, gastrointestinal varices are relatively rare, but they are clinically important because they tend to bleed massively. Color Doppler sonography is now widely used to diagnose the collaterals, but few color Doppler findings of gastric or intestinal varices have been reported. The aim of this study was to investigate the sonographic and color Doppler findings of gastrointestinal varices and to determine the role of color Doppler sonography in the diagnosis of these varices.

METHODS

We studied 30 patients who were diagnosed by endoscopy as having gastrointestinal varices (24 gastric, four duodenal, two intestinal) with color Doppler sonography and compared the results with the clinical data. The causes of gastric varices included liver cirrhosis (16/24, 66.7%), idiopathic portal hypertension (3/24, 12. 5%), chronic pancreatitis with splenic vein thrombosis (2/24, 8.3%), congenital biliary atresia (1/24, 4.2%), congenital hepatic fibrosis (1/24, 4.2%), and unknown (1/24, 4.2%). The causes of duodenal varices included idiopathic portal hypertension with portal thrombosis (3/4, 75%) and liver cirrhosis (1/4, 25%).

RESULTS

The gastric wall at the fundus was thickened in 17 of 24 cases (70.8%) with gastric varices, and the duodenal wall was thickened in four of four cases (100%) with duodenal varices. Sonography revealed thrombosis in the splenic vein in two of two cases with gastric varices secondary to chronic pancreatitis and in the confluence of the superior mesenteric vein and the splenic vein in three of four cases with duodenal varices. Color Doppler sonography demonstrated multiple, slow constant blood flows in the thickened wall in 15 of 24 cases (62.5%) with gastric varices and in four of four cases (100%) with duodenal varices. It demonstrated accumulated slow constant blood flows in the cecum in the case with cecal varices. Color Doppler showed also the communication between the varices and the neighboring vascular system (superior mesenteric vein and inferior vena cava) in the case with cecal varices, but it did not directly reveal such a communication in the other 29 cases (96.7%). Color Doppler showed a hepatofugal flow in the left gastric vein in all the hemorrhagic gastric varicose patients with esophageal varices, but it showed a hepatopetal flow in the left gastric vein in the isolated nonhemorrhagic gastric varicose patients.

CONCLUSION

Color Doppler sonography was very useful for the diagnosis of gastric and duodenal varices and for visualizing fine venous flows in the thickened gastric or duodenal wall. When it shows portal thrombosis in the confluence of the splenic vein and the superior mesenteric vein, duodenal varices should be suspected. The flow direction of the left gastric vein helps to differentiate hemorrhagic gastric varices from nonhemorrhagic ones.

Alpha-pompilidotoxin (alpha-PMTX), a novel neurotoxin from the venom of a solitary wasp, facilitates transmission in the crustacean neuromuscular synapse

A new neurotoxin, named alpha-pompilidotoxin (alpha-PMTX) has been found in the venom of the solitary wasp Anoplius safnariensis. In the neuromuscular synapse of the lobster walking leg preparation, alpha-PMTX (10-100 micro/M) caused great enhancement of both the excitatory and inhibitory postsynaptic potentials. Recordings of the excitatory post synaptic currents (EPSCs) at the synaptic sites showed that alpha-PMTX reversibly and dose-dependently potentiates EPSCs. Alpha-PMTX may act primarily on the presynaptic membrane but the mode of action of the toxin is clearly different from other known facilitatory neurotoxins, such as alpha-latrotoxin, apamin or charybdotoxin. This novel toxin will serve as a useful tool in the research field of neuroscience.

[Pharmacokinetic studies of all-trans retinoic acid (ATRA) and pilot study of intermittent schedule of ATRA and chemotherapy in childhood acute promyelocytic leukemia. Children's Cancer and Leukemia Study Group]

A pharmacokinetic study of all-trans retinoic acid (ATRA) was performed in 8 patients with various types of leukemia and MDS. After oral administration at a dose of 30 mg/m2, the mean peak plasma concentration was 430 ng/ml and was reached at 150 min. In one patient who failed to respond a very low plasma ATRA level was seen. Though the plasma ATRA exposure decreased significantly with daily drug administration, an intermittent schedule of ATRA administration would yield higher plasma drug concentrations. We treated 2 patients with refractory acute promyelocytic leukemia (APL) in a pilot study of ATRA followed by intensive chemotherapy (APL-ATRA protocol). Two patients successfully achieved complete remission with ATRA after failing under conventional chemotherapy. Based on the pharmacokinetic study of ATRA, an intermittent schedule of ATRA in addition to chemotherapy suggests an effective regimen for children with APL. Phase II trials to evaluate the role of intermittent schedules of ATRA are planned in Children's Cancer and Leukemia Study Group.

Isolated splenic metastases

We analyzed the primary tumors, sonographic findings, clinical manifestations, and prognosis in five cases of isolated splenic metastases to determine in what situations these rare metastases should be suspected. The metastases were detected by ultrasonography in all five patients, and the primary tumors were colonic cancer in four patients and renal cancer in one patient. Splenectomy was performed and the postoperative course was uneventful in all patients. We conclude that preoperative and follow-up examinations must be performed with special attention given to the spleen in colonic or renal cancer patients.

The pathway of ammonia assimilation in the silkworm, Bombyx mori

Ammonia can easily be assimilated into amino acids and used for silk-protein synthesis in the silkworm, Bombyx mori. To determine the metabolic pathway of ammonia assimilation, silkworm larvae were injected with methionine sulfoximine (MS), a specific inhibitor of glutamine synthetase (GS). Activity of GS in the fat body 2h after treatment with 400&mgr;g MS decreased to less than 10% of the control activity, whereas MS had no effect on the activity of glutamate dehydrogenase (GDH), another enzyme which could possibly be responsible for ammonia assimilation. Glutamine concentration in the hemolymph rapidly decreased after MS treatment, while the ammonia level in the hemolymph sharply increased. Glutamine concentration in the hemolymph 4h after injection decreased with increasing doses of MS, whereas ammonia concentration increased in proportion to the MS dose. MS strongly blocked the incorporation of (15)N label into silk-protein in larvae injected with (15)N ammonia acetate, while it slightly inhibited the incorporation of (15)N-amide glutamine into silk-protein. These results suggest that ammonia is mainly assimilated into glutamine via the action of GS and then converted into other amino acids for silk-protein synthesis and that GDH does not play a major role in ammonia assimilation in B. mori.

Novel hepatitis C virus protease inhibitors: thiazolidine derivatives

This study evaluated the inhibitory effects of thiazolidine derivatives on hepatitis C virus (HCV) protease and other human serine proteases. The inhibition efficacy was tested with a reversed-phase high-performance liquid chromatography (HPLC) assay system using a NS3-NS4A fusion protein as the HCV protease and a synthetic peptide substrate that mimics the NS5A-5B junction. Nine thiazolidine derivatives showed more than 50% inhibition at 50 microg/ml. The most potent derivative was RD4-6250, with 50% inhibition at a concentration of 2.3 microg/ml; this concentration was lower than those of other protease inhibitors reported previously. The most selective derivative was RD4-6205, with 50% inhibition at a concentration of 6.4 microg/ml, a lower concentration than those on other serine proteases (chymotrypsin, trypsin, plasmin, and elastase). These results suggest that the RD4-6205 skeleton is an important structure for inhibitory activity on the HCV protease NS3-NS4A.

5-Hydroxytryptamine inhibits Na absorption and stimulates Cl secretion across canine tracheal epithelial sheets

BACKGROUND

5-Hydroxytryptamine (5-HT) can be released from mast cells and platelets through an IgE-dependent mechanism and may play a role in the pathogenesis of allergic bronchoconstriction. However, the effect of 5-HT on ion transport by airway epithelium remains uncertain.

OBJECTIVE

To determine whether 5-HT alters electrical and ion transport properties of Cl-secreting epithelia and, if so, what subtype of 5-HT receptors is involved, we studied canine tracheal epithelium under short-circuit conditions in vitro.

METHODS

Canine tracheal mucosa was mounted in Lucite half-chambers and the responses of short-circuit current (lsc), transepithelial potential difference (PD) and tissue conductance (G) were measured. In addition, ion fluxes were directly measured using 22Na and 36Cl.

RESULTS

Mucosal addition of 5-HT caused a rapid increase in lsc, which was accompanied by the increases in PD and G, whereas submucosal 5-HT had no effect. In the presence of amiloride, 5-HT and its receptor agonists dose-dependently increased lsc, with the rank order of potency being 5-HT > alpha-methyl-5-HT > 2-methyl-5HT > 5-carboxamidotryptamine. The effect of 5-HT was inhibited by ketanserin and spiperone but not by ondansetron. 5-HT increased Cl flux from the submucosa to the mucosa with a slight inhibition of Na flux to the opposite direction.

CONCLUSION

5-HT inhibits airway epithelial Na absorption and stimulates Cl secretion. The latter action predominates the former and is mediated by 5-HT2 receptors. These effects may result in the increase in water movement toward the airway lumen.

Effect of ultraviolet radiation on the infectivity of Taenia taeniaeformis eggs

The effect of ultraviolet (UV) radiation on the infectivity of Taenia taeniaeformis eggs was observed. The eggs were exposed to various UV doses and orally inoculated to rats. The number of cysts and lesions decreased dose-dependently, and neither cyst nor lesion was observed from rats infected with eggs exposed to a total dose of 2,880 mJ/cm2 or more. For evaluation of protective role of embryophore against UV radiation, the onchospheres with/without embryophore were exposed to UV radiation. Remarkably lower numbers of cyst and lesions were observed in rats inoculated with eggs which were exposed to a total dose of 30 mJ/cm2 or more after removal of embryophore. These results suggested an importance of the protective function of the embryophore in the protection against UV radiation.

Stimulation of airway mucociliary transport and epithelial ciliary motility by the triazolopyridazin derivative TAK-225

To elucidate whether a newly developed antiallergic drug, the triazolopyridazin derivative TAK-225, alters airway mucociliary clearance and, if so, what the mechanism of action is, we measured mucociliary transport in the rabbit tracheal mucosa ex vivo and ciliary motility of the tracheal epithelium in vitro. Mucociliary transport function was determined by the transport rate of Evans blue dye that had been placed on the mucosal surface above the carina. Oral administration of TAK-225 (0.3-30 mg/kg) increased Evans blue transport toward the larynx in a dose-dependent manner. Addition of TAK-225 caused a rapid and sustained increase in the ciliary beat frequency of tracheal epithelium, as assessed by photoelectric method; the maximal increase from the base-line value was 25.1 +/- 4.6% (P < .01), and the concentration required to produce a half-maximal effect (EC50) was 3.1 +/- 0.8 x 10(-7) M. This effect was greatly attenuated by pretreatment with the cAMP antagonist adenosine 3',5'-cyclic monophosphorothioate, but not by Ca++-free medium containing ethylene glycol-bis [3-aminoethyl ether] N,N,N',N'-tetraacetic acid and [1,2-bis(2)aminophenoxy]ethane N,N,N',N'-tetraacetic acid-acetomethoxy ester. Incubation of tracheal epithelium with TAK-225 increased intracellular cAMP contents in a concentration-dependent manner. These results suggest that TAK-225 enhances airway mucociliary clearance probably through cAMP-mediated stimulation of ciliary motility of airway epithelium.

Role of Ca(2+)-activated K+ channel in epithelium-dependent relaxation of human bronchial smooth muscle

1. To elucidate whether K+ channels play a role in the action of epithelium-dependent bronchodilatation, we studied responses in human bronchial strips in the presence of indomethacin and NG-nitro-L-arginine methylester under isometric conditions, in vitro. 2. Mechanical removal of the epithelium increased the contractile responses to acetylcholine; the pD2 values increased from 5.0 +/- 0.2 to 5.9 +/- 0.3 (P < 0.001). This potentiation was abolished by iberiotoxin but not by apamin or glibenclamide. 3. In cascade bioassay, application of the bathing medium from dispersed, bronchial epithelial cells to epithelium-denuded bronchial strips decreased acetylcholine-induced contraction by 44 +/- 6%. This effect was reduced to 10 +/- 3% (P < 0.01) when the epithelial cells were pretreated with iberiotoxin, and to 4 +/- 1% (P < 0.001) when the epithelial cells were incubated with Ca(2+)-free medium containing [1,2-bis(2) aminophenoxy] ethane N,N,N',N'-tetraacetic acid-acetomethoxy ester. 4. In contrast, the bronchodilator effect of the medium bathing epithelial cells was not altered by the direct addition of iberiotoxin to epithelium-denuded tissues. 5. These results suggest that the Ca(2+)-activated K+ channel may play a role in the synthesis and/or release of smooth muscle relaxing factor, which is neither nitric oxide nor a cyclo-oxygenase product, from airway epithelial cells.

Portal vein aneurysm: report of six cases and review of the literature

Portal vein aneurysm is very rare, and its relation to portal hypertension has been emphasized. We report six cases of portal vein aneurysm (five extrahepatic and one intrahepatic). All patients were asymptomatic and had no signs suggestive of portal hypertension; the lesion was incidentally detected by ultrasound. Color Doppler sonography showed a constant hepatopetal flow along the aneurysmal wall, which immediately led to the diagnosis. We stress the usefulness of color Doppler sonography for studying the hemodynamics of this vascular anomaly and briefly review the literature.

Leukotriene antagonist prevents exacerbation of asthma during reduction of high-dose inhaled corticosteroid. The Tokyo Joshi-Idai Asthma Research Group

To test whether the leukotriene antagonist ONO-1078 (pranlukast) prevents asthma exacerbations during reduction of high-dose inhaled corticosteroid, we conducted a randomized, double-blind, placebo-controlled study in 79 asthma patients requiring high doses (1,500 microg/d or more) of inhaled beclomethasone dipropionate (BDI) for clinical control (duration of asthma, 11.0 +/- 3.1 yr; duration of BDI treatment, 0.5 +/- 0.3 yr; FEV1 percentage of predicted, 80.7 +/- 2.0%). After a 2-wk run-in period, the doses of BDI were halved, while the patients were assigned to receive orally ONO-1078, 450 mg twice daily, or placebo. In the placebo group FEV1 decreased by 0.33 +/- 0.20 L after 6 wk (p < 0.001). Likewise, morning and evening PEF decreased by 46 +/- 7 L/min and 18 +/- 6 L/min, respectively. By contrast these variables were sustained above baseline in the ONO-1078 group. The number of daytime and nighttime asthma symptoms and the use of beta2-agonist increased in the placebo group, whereas they remained unchanged in the ONO-1078 group. In the placebo group concentrations of serum eosinophil cationic protein and exhaled nitric oxide increased (p = 0.007 and p = 0.025, respectively), compared with no change in the ONO-1078 group. Therefore, the leukotriene antagonist ONO-1078 prevents the asthma deterioration provoked by a 6-wk reduction of the dose of inhaled BDI into half.

Temocaprilat, a novel angiotensin-converting enzyme inhibitor, is excreted in bile via an ATP-dependent active transporter (cMOAT) that is deficient in Eisai hyperbilirubinemic mutant rats (EHBR)

Temocapril x HCl (alpha-((2S,6R)-6-[(1S)-1-ethoxy-carbonyl-3-phenyl-propyl]amino-5-oxo-2- (2-thienyl)perhydro-1,4-thiazepin-4-yl)acetic acid hydrochloride) is a novel prodrug of an angiotensin-converting enzyme (ACE) inhibitor. Unlike many other ACE inhibitors, its pharmacologically active metabolite,temocaprilat, is excreted predominantly in bile. To investigate the mechanism for the biliary excretion of temocaprilat, we performed in vivo and in vitro experiments using mutant Eisai hyperbilirubinemic rats EHBR) whose canalicular multispecific organic anion transporter (cMOAT) is hereditarily defective. Biliary clearance of temocaprilat after i.v. administration of [14C]temocapril x HCl (1.0 mg/kg) in EHBR was significantly lower than that in Sprague-Dawley rats (5.00 ml/min/kg for Sprague-Dawley rats vs. 0.25 ml/min/kg for EHBR). The uptake of temocaprilat into canalicular membrane vesicles (CMVs) prepared from Sprague-Dawley rats was stimulated in the presence of ATP, whereas little stimulation was observed in CMVs from EHBR. The initial uptake rate of ATP-dependent transport of temocaprilat showed saturation kinetics; we obtained an apparent V(max) value of 1.14 nmol/min/mg protein and a K(m) value 92.5 microM. ATP-dependent transport of temocaprilat was competitively inhibited by 2,4-dinitrophenyl-S-glutathione, a typical substrate for cMOAT with an inhibition constant (K(i)) of 25.8 microM. The K(m) value for the uptake of 2,4-dinitrophenyl-S-glutathione into CMVs (K(m) = 29.6 microM) was consistent with this K(i) value. In addition, the ATP-dependent uptake of 2,4-dinitrophenyl-S-glutathione was inhibited by temocaprilat in a concentration-dependent manner. Active forms of some ACE inhibitors (benazepril, cilazapril, delapril, enalapril and imidapril) did not affect the transport of temocaprilat into CMVs even at concentrations as high as 200 microM. These data suggest that temocaprilat is effectively excreted in bile via cMOAT that is deficient in EHBR and that many of other ACE inhibitors have low affinity for cMOAT.

Effect of adenosine on adrenergic neurotransmission and modulation by endothelium in canine pulmonary artery

To determine the effect of adenosine on adrenergic neurotransmission in pulmonary vasculature and its modulation by endothelial cells, we studied canine pulmonary arteries under isometric conditions in vitro. Adenosine decreased the contractile responses to electrical field stimulation but had no effect on those to norepinephrine. This inhibitory effect was concentration dependent, with a rank order of potency of NECA > 2-chloroadenosine > adenosine >> APNEA (an A3-adenosine-receptor agonist) > CGS-21680 (an A2a agonist) > CCPA (an A1 agonist). Adenosine reduced the electrical field stimulation-evoked 3H overflow in superfused pulmonary artery previously soaked in [3H]norepinephrine. Pretreatment with the adenosine uptake blocker dipyridamole or the adenosine deaminase inhibitor deoxycoformycin enhanced the adenosine action, and this enhancement was not observed in the endothelium-denuded tissues. Adenosine deaminase activity was found in endothelial cells. Therefore, adenosine inhibits norepinephrine release via an A2b-receptor mechanism, an effect that may be modulated by uptake and metabolism by endothelial cells.

Accuracy of liver puncture under US guidance: re-evaluation by microcomputer simulation model

OBJECTIVE

To evaluate, using microcomputer simulation models, the degree of distortion of the puncture needle in sonograms used during a liver puncture under ultrasound guidance.

METHODS

We made a simplified simulation model of the puncture needle passing through the abdominal wall to the target lesion in the liver (cases without ascites), and additionally through ascites between the abdominal wall and the liver (cases with ascites), to evaluate the degree of distortion of the puncture needle in the sonogram. We considered the thicknesses and sound velocities of the abdominal wall and the ascites fluid, as well as the puncture angle, on the degree of distortion.

RESULTS

(1) Cases without ascites: The puncture needle displayed on sonogram shifted predominantly anteriorly with a displacement error between 6 mm forward and 1 mm backward and with an angular error between 2.2 degrees forward and 0.1 degree backward when the abdominal wall was muscular, and the pattern of distortion had an inverted S-shape. It was displayed predominantly posteriorly with a displacement error between 14 mm backward and 2 mm forward and with an angular error between 3.7 degrees backward and 1.2 degrees forward when the abdominal wall was fatty, and the pattern was S-shaped. Regardless of the composition of the abdominal wall, when the abdominal wall was thin, the more obtuse the puncture angle was, the larger the shift was, and when the abdominal wall was thick, the more acute the puncture angle was, the larger the shift was. (2) Cases with ascites: (a) Regardless of the quantity and sound velocity of the ascites, the puncture needle shifted predominantly anteriorly with a displacement error between 7 mm forward and 3 mm backward and with an angular error between 3.1 degrees forward and 1.9 degrees backward when the abdominal wall was muscular, and showed the inverted S-shaped pattern. In contrast, it shifted predominantly posteriorly with a displacement error between 17 mm backward and 5 mm forward and with an angular error between 3.7 degrees backward and 3.9 degrees forward when the abdominal wall was fatty, and showed the S-shaped pattern. (b) Regardless of the sound velocity of the ascites fluid and the composition of the abdominal wall, the shift of the puncture needle changed little with differing amounts of ascites.

CONCLUSION

It is highly recommended that a liver puncture under US guidance be performed taking into account the pattern of distortion of the puncture needle in each situation.

[Effect of heparin on the increase in intracellular calcium caused by inositol 1,4,5-triphosphate in airway epithelial cells]

We studied the effect of heparin on the inositol 1,4,5-triphosphate (IP3)-dependent increase in intracellular calcium (Ca2+) caused by ATP. The Ca2+ concentration ([Ca2+]i) in cultured epithelial cells from cow tracheas was measured by the fura-2 method. ATP (10(-4) M) stimulated IP3 production and caused a biphasic increase in [Ca2+]i a transient response and a subsequent sustained response. Heparin (l 100 U/ml) dose-dependently inhibited the ATP-induced increase in [Ca2+]i but had no effect on IP3 production. Dextran sulfate, a polysaccharide with negative charge density, had a similar inhibitory effect on the ATP-induced increase in [Ca2+]i. These data suggest that heparin inhibits intracellular Ca2+ mobilization by acting at a site "distal to" IP3 production, and that the mechanism of action of heparin may be related to its negative charge.

Histamine H2 receptor-mediated airway goblet cell secretion and its modulation by histamine-degrading enzymes

BACKGROUND

Airway goblet cell hypersecretion may contribute to the pathophysiology of asthma. However, it is unknown whether histamine affects goblet cell secretion and, if so, which subtype of histamine receptor is involved and whether endogenous histamine-degrading enzymes modulate these actions.

METHODS

We morphometrically assessed goblet cell secretion in the guinea pig trachea stained with alcian blue and periodic acid Schiff stains by measuring the mucus score, which was inversely related to the degree of mucus glycoprotein discharge.

RESULTS

Inhalation of histamine caused a dose-dependent decrease in mucus score, an effect that was inhibited by pretreatment with the H2-receptor antagonist cimetidine but not with the H1-receptor antagonist mepyramine or the H3-receptor antagonist thioperamide. Inhaled Dimaprit, a selective H2-receptor agonist, likewise decreased mucus score; whereas stimulation of H1- and H3-receptors with 2-methylhistamine and (R)-alpha-methylhistamine, respectively, had no effect. Pretreatment with the histamine N-methyltransferase inhibitor SKF 91488, but not the diamine oxidase inhibitor aminoguanidine, potentiated the dose-dependent effect of histamine on goblet cell secretion, causing a decrease in the concentration of inhaled histamine required to produce a half-maximal effect from 0.80 +/- 0.12 to 0.48 +/- 0.09 mg/ml (p < 0.01). The histamine methyltransferase activity in the tracheal mucosa was 29 times higher than diamine oxidase activity.

CONCLUSION

These findings suggest that histamine stimulates airway goblet cell secretion through H2-receptors and that this effect may be modulated principally by endogenous histamine methyltransferase through a degradation of histamine.

Synthesis and biological activity of a 1 alpha,25-dihydroxyvitamin D2 analog bearing an amide group in the side-chain

Synthesis of a 1 alpha,25-dihydroxyvitamin D2 analog (3), in which the double bond in the side-chain is replaced by an amide group, is described. Condensation of a carboxylic acid (8) with an amine (6) gave an amide (9), which in turn led to 3 via several steps. The analog (3) could not bind to the chick cytosol vitamin D receptor, which indicated the importance of the hydrophobic interaction of the C(22)-C(23) double bond in 1 alpha,25-dihydroxyvitamin D2 (2) with the vitamin D receptor.

Thiadiazole derivatives: highly potent and selective inhibitors of human immunodeficiency virus type 1 (HIV-1) replications in vitro

We have recently reported that thiadiazole (TDA) derivatives are highly potent inhibitors of human immunodeficiency virus type 1 (HIV-1) replication. These compounds belong to the family of nonnucleoside reverse transcriptase inhibitors (NNRTIs). In an attempt to develop more effective and pharmacologically favorable compounds, novel TDA derivatives have been synthesized and examined for their anti-HIV-1 activity in vitro. Among them, RD4-2217 was found to be the most potent inhibitor of HIV-1 replication. It inhibited replication of the HTLV-IIIB strain in MT-4 cells at a concentration of 6 nM. RD4-2217 was also inhibitory to clinical isolates and zidovudine-resistant mutants of HIV-1. The combination of RD4-2217 with zidovudine or the protease inhibitor A-75925 synergistically inhibited HIV-1 replication. Studies on the emergence of drug-resistant mutants revealed that, although much higher concentrations (1-10 microM) were required, RD4-2217 completely suppressed the breakthrough of HIV-1 in the supernatants during long-term culturing of infected cells. Furthermore, RD4-2217 at low concentrations (10 or 100 nM), in combination with zidovudine, also completely inhibited viral breakthrough. In addition, RD4-2217 had lower lipophilicity and improved protein binding as compared to its congener RD4-2024 and loviride. These results suggest that RD4-2217, one of the TDA derivatives, is worth pursuing as a candidate drug for the treatment of HIV-1 infections.