Macronodular hepatic deformity on normal liver

BACKGROUND AND METHODS

Macronodular hepatic deformity on normal liver is very rare. We present nine such cases and try to define the characteristic clinical and ultrasound (US) findings.

RESULTS

In the left lobe, the lateral segment was replaced by multiple nodules and the medial segment was very atrophied and irregularly shaped. Compared with the left lobe, the right lobe showed very few abnormalities except for segment 6, which showed a macronodular deformity. These nodules, regardless of diameter or lobe, showed a relatively homogeneous internal structure and were isoechoic relative to the surrounding hepatic parenchyma. These multinodular changes on US corresponded to multiple regenerative nodules identified at laparoscopic evaluation. On color Doppler US and angiography, the major intrahepatic vessels were patent in all cases.

CONCLUSION

Although relatively rare, the macronodular hepatic deformity on normal liver collected in our series showed a characteristic appearance by US. A good understanding of its characteristics may help sonographers in differentiating it from other, more common hepatic deformities.

Structure and biological activities of eumenine mastoparan-AF (EMP-AF), a new mast cell degranulating peptide in the venom of the solitary wasp (Anterhynchium flavomarginatum micado)

A new mast cell degranulating peptide, eumenine mastoparan-AF (EMP-AF), was isolated from the venom of the solitary wasp Anterhynchium flavomarginatum micado, the most common eumenine wasp found in Japan. The structure was analyzed by FAB-MS/MS together with Edman degradation, which was corroborated by solid-phase synthesis. The sequence of EMP-AF, Ile-Asn-Leu-Leu-Lys-Ile-Ala-Lys-Gly-Ile-Ile-Lys-Ser-Leu-NH(2), was similar to that of mastoparan, a mast cell degranulating peptide from a hornet venom; tetradecapeptide with C-terminus amidated and rich in hydrophobic and basic amino acids. In fact, EMP-AF exhibited similar activity to mastoparan in stimulating degranulation from rat peritoneal mast cells and RBL-2H3 cells. It also showed significant hemolytic activity in human erythrocytes. Therefore, this is the first example that a mast cell degranulating peptide is found in the solitary wasp venom. Besides the degranulation and hemolytic activity, EMP-AF also affects on neuromuscular transmission in the lobster walking leg preparation. Three analogs EMP-AF-1 approximately 3 were snythesized and biologically tested together with EMP-AF, resulting in the importance of the C-terminal amide structure for biological activities.

Crystallization and preliminary X-ray diffraction analysis of a eumenine mastoparan toxin: a new class of mast-cell degranulating peptide in the wasp venom

Mastoparans are tetradecapeptides found to be the major component of vespid venoms. A mastoparan toxin isolated from the venom of Anterhynchium flavomarginatum micado has been crystallized and X-ray diffraction data collected to 2.7 A resolution using a synchrotron-radiation source. Crystals were determined to belong to the space group P6(2)22 (P6(4)22). This is the first mastoparan to be crystallized and will provide further insights into the conformational significance of mastoparan toxins with respect to their potency and activity in G-protein regulation.

Early structural changes in myosin rod upon heating of carp myofibrils

Upon heating carp myofibrils at 40 degrees C, the amount of myosin that is soluble and monomeric dropped very quickly, roughly 5 times faster than the ATPase inactivation. This rapid decrease of solubility was well explained by a rapid denaturation of the rod portion as measured by chymotryptic digestibility. Chymotryptic digestion of heated myofibrils in a low-salt medium with EDTA generated a reduced amount of rod and subfragment-1 (S-1). The decrease of S-1 produced from the heated myofibrils was consistent with the ATPase inactivation. The decrease of rod produced from the heated myofibrils was explained by the increased susceptibility of the heavy meromyosin (HMM)/light meromyosin (LMM) junction to chymotryptic. It was, therefore, concluded that the fastest event occurring in the myosin molecule upon heating of myofibrils is the irreversible exposure of the HMM/LMM junction.

Retroperitoneal liposarcoma: sonographic findings

This study, based on sonographic (US) results of 10 cases with histologically proven retroperitoneal liposarcoma (eight well-differentiated and two pleomorphic types), shows that the presence of fine echogenic lines within the tumor is a useful sign for diagnosing a well-differentiated liposarcoma. Presence of numerous fine fibrous septa in the lipomatous tumor tissue is thought to be responsible for this interesting phenomenon. Of interest is the fact that the direction of these lines changed according to the probe format used: parallel horizontal lines when using a linear probe and concentric lines converging toward the probe when using a sector or curved linear probe. In contrast, pleomorphic liposarcoma does not show this US sign. Knowledge of these US findings is useful for the diagnosis of retroperitoneal liposarcoma.

Abdominal involvement in neurofibromatosis 1: sonographic findings

BACKGROUND

Neurofibromatosis 1 (NF1) has been studied from many viewpoints, but its abdominal involvement has rarely been reported. Sonography (US) is now the initial diagnostic tool for abdominal exploration, which prompted us to determine the clinical manifestations and US findings of abdominal involvement in NF1.

METHODS

We analyzed the US findings and clinical data of eight NF1 cases with abdominal involvement.

RESULTS

Abdominal involvement included neurofibromatous tumor growth in the liver, mesentery, and retroperitoneum, in addition to mesenteric leiomyomatosis and gastric carcinoma. Color Doppler US was useful not only in detecting blood flows in the lesions but also in preventing hazardous vascular injury during tumor biopsy.

CONCLUSION

A better understanding of the clinical manifestations and US findings of abdominal involvement in NF1 translates into improved NF1 patient care.

Long-standing painless intussusception in adults

Long-standing painless intussusception in adults is considered to be rare. We report three such cases with an emphasis on color Doppler results. In our three cases the indication for abdominal US was a palpable mass in all these cases, and intussusception was detected by US at a time when the patients had only very mild abdominal discomfort. Persistence of sufficient blood flow, as was suggested by the color Doppler results, was thought to be the most likely pathomechanism of long-standing painless intussusception. The underlying disease was tuberculosis in two of the three cases. Thus, when encountering patients with painless intussusception, tuberculosis must be kept in mind.

Ovarian and retroperitoneal teratomas in a dog

A 2-year-old female Labrador retriever was presented with anorexia and abdominal distention. Laparotomy revealed the presence of a 31-cm ovoid mass in the portion of the left ovary and an 11-cm round mass in the left retroperitoneal region. Both masses were surgically removed. Histopathological examination of the masses revealed a mixture of tissues characteristic of teratomas, such as multiple bronchial and intestinal cysts, hair follicles, sebaceous and apocrine sweat glands, and neuron tissue with intervening cartilage, bone and fat tissue. This paper appears to be the first report of primary retroperitoneal teratoma in the dog.

Chilaiditi syndrome: sonographic findings

BACKGROUND AND METHODS

Sonographic (US) findings of Chilaiditi syndrome have been rarely reported in the literature. We reviewed 18 cases of Chilaiditi syndrome to pinpoint its US pattern.

RESULTS

(1) US showed gas echoes of different sizes superimposed over the entire liver in two cases and over the right hepatic lobe in six cases, leading to a high suspicion of Chilaiditi syndrome. (2) US showed a small gas echo in the hepatodiaphragmatic space, mimicking pneumoperitoneum in eight cases. In this instance, altering the patient's position allowed for confirmation of the lack of a change in the location of the gas echo, unlike cases of pneumoperitoneum. (3) The hepatic surface appeared as a hyperechoic mass in two cases.

CONCLUSION

Knowledge of US patterns of Chilaiditi syndrome helps avoid confusion with pneumoperitoneum or hepatic masses.

Adenosquamous carcinoma of the pancreas: report of two cases

Adenosquamous carcinoma (ASqC) of the pancreas is a rare tumor. We analyzed the radiologic findings and clinical manifestations in two such cases. In both cases (a 51-year-old woman and a 67-year-old man), the portal system was selectively and largely invaded, the superior mesenteric vein in one and the splenic vein in the other, without arterial invasion. Thus, peripancreatic vessels should be carefully observed in patients with ASqC of the pancreas. One case showed an unusual mode of spread. Only a huge metastatic lesion was initially detected, leading to the misdiagnosis of primary malignant mesenteric tumor. Such an unusual growth pattern is also worth noting.

A new class of neurotoxin from wasp venom slows inactivation of sodium current

The effects of alpha-pompilidotoxin (alpha-PMTX), a new neurotoxin isolated from the venom of a solitary wasp, were studied on the neuromuscular synapses in lobster walking leg and the rat trigeminal ganglion (TG) neurons. Paired intracellular recordings from the presynaptic axon terminals and the innervating lobster leg muscles revealed that alpha-PMTX induced long bursts of action potentials in the presynaptic axon, which resulted in facilitated excitatory and inhibitory synaptic transmission. The action of alpha-PMTX was distinct from that of other known facilitatory presynaptic toxins, including sea anemone toxins and alpha-scorpion toxins, which modify the fast inactivation of Na+ current. We further characterized the action of alpha-PMTX on Na+ channels by whole-cell recordings from rat trigeminal neurons. We found that alpha-PMTX slowed the Na+ channels inactivation process without changing the peak current-voltage relationship or the activation time course of tetrodotoxin (TTX)-sensitive Na+ currents, and that alpha-PMTX had voltage-dependent effects on the rate of recovery from Na+ current inactivation and deactivating tail currents. The results suggest that alpha-PMTX slows or blocks conformational changes required for fast inactivation of the Na+ channels on the extracellular surface. The simple structure of alpha-PMTX, consisting of 13 amino acids, would be advantageous for understanding the functional architecture of Na+ channel protein.

Syntheses and biological evaluation of novel 2alpha-substituted 1alpha,25-dihydroxyvitamin D3 analogues

Novel 2alpha-substituted 1alpha,25-dihydroxyvitamin D3 analogues were efficiently synthesized and their biological activities were evaluated. 2alpha-Methyl-1alpha,25-dihydroxyvitamin D3 (2), whose unique biological activities were previously reported, was modified to 2alpha-alkyl (ethyl and propyl) and 2alpha-hydroxyalkyl (hydroxymethyl, hydroxyethyl, and hydroxypropyl) analogues 3-7 by elongation of the alkyl chain and/or introduction of a terminal hydroxyl group. 2alpha-Hydroxypropyl-1alpha,25-dihydroxyvitamin D3 (7) exhibited an exceptionally potent calcium-regulating effect and a unique activity profile.

Molecular determinants of binding of a wasp toxin (PMTXs) and its analogs in the Na+ channels proteins

The structural specificity of alpha-PMTX, a novel peptide toxin derived from wasp venom has been studied on the neuromuscular synapse in the walking leg of the lobster. alpha-PMTX is known to induce repetitive action potentials in the presynaptic axon due to sodium channel inactivation. We synthesized 29 analogs of alpha-PMTX by substituting one or two amino acids and compared threshold concentrations of these mutant toxins for inducing repetitive action potentials. In 13 amino acid residues of alpha-PMTX, Arg-1, Lys-3 and Lys-12 regulate the toxic activity because substitution of these basic amino acid residues with other amino acid residues greatly changed the potency. Determining the structure-activity relationships of PMTXs will help clarifying the molecular mechanism of sodium channel inactivation.

Mesenteric cyst: sonographic findings

BACKGROUND

Mesenteric cyst (MC) is a relatively rare disease, and its sonographic characteristics have not been sufficiently analyzed.

METHODS

We studied the sonographic findings of eight patients with MC, with attention paid to its size, shape, internal echoes, and especially the presence or absence of lateral shadowing and the mode of back echoes. In four cases, the sound velocity and acoustic impedance of cystic fluid were also measured. The mode of blood flow was evaluated by color Doppler sonography.

RESULTS

Six cases showed an oval or comma-shaped mass. Internal echoes were present in six cases, and two of them showed a pseudosolid pattern. In these cases, M-mode sonography confirmed the movement of these internal echoes. Only one case showed a posterior echo enhancement, and no case showed lateral shadowing. Sound velocity measured in four cases was 1,515-1,537 m/s, with an acoustic impedance of 1.550-1.576 kg/m2/s. No blood flow signals were obtained from the lesion.

CONCLUSION

MC exhibits so many patterns on ultrasound that we should consider the possibility of MC when encountering an avascular oval mesenteric mass.

Congenital absence of the horizontal portion of the left portal vein: ultrasound findings

Congenital absence of the horizontal portion of the left portal vein is very rare and has been very reported sporadically. We present three such cases referred from other hospitals with a diagnosis of intrahepatic vascular anomaly. Color Doppler ultrasound not only confirmed the diagnosis but also allowed a quantitative measurement of blood flow in these cases. Although it is a very rare condition, knowledge of the ultrasound and color Doppler findings helps in establishing the diagnosis of this congenital anomaly.

Novel ring A stereoisomers of 2-methyl-1alpha,25-dihydroxyvitamin D(3) and 2-methyl-20-epi-1alpha,25-dihydroxyvitamin D(3): transactivation of target genes and modulation of differentiation in human promyelocytic leukemia (HL-60) cells

We evaluated the biological activity of two sets of ring A stereoisomers of 2-methyl-1alpha,25-dihydroxyvitamin D(3) (2-methyl-1alpha,25(OH)(2)D(3)) and 2-methyl-20-epi-1alpha, 25-dihydroxyvitamin D(3) (2-methyl-20-epi-1alpha,25(OH)(2)D(3)) in terms of the following: transactivation of a rat 25-hydroxyvitamin D(3)-24-hydroxylase gene promoter including two vitamin D response elements (VDREs) and a human osteocalcin gene promoter including a VDRE in transfected human osteosarcoma (MG-63) cells; a vitamin D receptor (VDR)-mediated response using a VDR-GAL4 one-hybrid luciferase reporter system and a retinoid X receptor alpha (RXRalpha)-mediated response using an expressed VDR/RXRalpha-GAL4 modified two-hybrid luciferase reporter system in transfected human epitheloid carcinoma, cervix (HeLa) cells; and modulation of cell surface CD11b antigen expression in human leukemia (HL-60) cells. All the diastereomers of both analogues exhibited unique biological activity profiles depending upon the configurations of the C-1 and C-3 hydroxyl groups, the C-2 methyl group in ring A, and the C-20 methyl group in the side chain. Of the eight possible diastereomers of the 2-methyl analogues, 2alpha-methyl-1alpha,25(OH)(2)D(3) was the most potent and exhibited comparable or even greater biological potency than 1alpha,25(OH)(2)D(3). Of the eight possible diastereomers of the 2-methyl-20-epi analogues, 2alpha-methyl-20-epi-1alpha,25(OH)(2)D(3) was the most potent and exhibited 100- to 200-fold higher transcriptional potencies than 1alpha,25(OH)(2)D(3) and exceptionally high cell regulatory activities. 2beta-methyl-20-epi-1alpha,25(OH)(2)D(3) was nearly as potent as its 2-epimer, 2alpha-methyl-20-epi-1alpha,25(OH)(2)D(3), whereas its 20-epimer, 2beta-methyl-1alpha,25(OH)(2)D(3), was almost completely biologically inactive. In these respects, it can be postulated that the double modification of 2-methyl substitution and 20-epimerization to 1alpha,25(OH)(2)D(3) induces remarkable changes in a VDR/RXRalpha/VDRE-mediated signaling response and greatly enhances biological activity. The other striking finding was that 2beta-methyl-20-epi-3-epi-1beta,25(OH)(2)D(3) is transcriptionally more active than 1alpha,25(OH)(2)D(3) despite lacking the 1alpha-hydroxyl group, which was believed to be essential for expressing VDR-mediated gene transcription. Since the C-20 natural counterpart, 2beta-methyl-3-epi-1beta,25(OH)(2)D(3), was almost completely biologically inactive, 20-epimerization is probably responsible for activation of gene expression. Although earlier extensive structure-activity studies of vitamin D analogues showed stereochemistry at the C-1, C-3, and C-20 of 1alpha,25(OH)(2)D(3) to be the key structural motif for vitamin D action, our results clearly demonstrated that stereochemistry at the C-2 is also an important structural motif for vitamin D action and imply that 2-methyl substitution possibly induces conformational changes in ring A depending upon the combinations of configurations of the C-1 and C-3 hydroxyl groups with C-20 stereochemistry. Consequently, several of these analogues exhibit exceptionally high or unexpected biological activities at the molecular and cellular levels. These results suggest that 2-methyl substitution together with alterations of stereochemistry in both ring A and the side chain of 1alpha, 25(OH)(2)D(3) will provide useful analogues for structure-activity studies and development of therapeutic agents with unique biological activity profiles.

Gallbladder carcinoma: color Doppler sonography

This study, based on color Doppler and pulsed Doppler sonographic results of 13 cases with gallbladder carcinoma, eight cases of adenomyomatosis, and eight cases of tumefactive biliary sludge, shows that the presence or absence of blood flow signals helps in the differentiation between gallbladder carcinoma and tumefactive biliary sludge (84.6% sensitivity and 80.0% specificity). However, color Doppler sonography is still not fully capable of distinguishing all gallbladder carcinoma, and a further increase in Doppler sensitivity is mandatory for this purpose. Visualization of high-velocity blood flow within the lesion made gallbladder carcinoma more likely than benign tumor. In contrast, there was no difference in the resistive index between gallbladder carcinoma, adenomyomatosis, and normal subject groups, and the significance of the resistive index is a subject of future study.

Mesenteric panniculitis: sonographic findings

BACKGROUND

Mesenteric panniculitis (MP) is a relatively rare disease, and sonographic (US) and color Doppler findings have been infrequently reported.

METHODS

We reviewed the clinical data and US and Doppler results of three cases of MP to determine the role and limitations of these techniques.

RESULTS

The sole presenting clinical sign was a soft mass. On US the lesion was imaged as a poorly margined echogenic mass with hypoechoic areas. Color Doppler US visualized the nondeviated mesenteric vessels within the mass, which enabled us to perform a safe guided biopsy.

CONCLUSIONS

US is useful as an initial diagnostic tool, but its results must be interpreted carefully. Color Doppler US is very useful in demonstrating fine vessels and helps in performing a safe needle biopsy.

Consequences of placing an intramolecular crosslink in myosin S1

This paper describes the placement of a crosslinking agent (dibromobimane) between two thiols (Cys-522 and Cys-707) of a fragment, "S1," of the motor protein, myosin. It turns out that fastening the first anchor of the crosslinker is easy and rapid, but fastening the second anchor (Cys-522) is very temperature dependent, taking 30 min at room temperature but about a week on ice. Moreover, crystallography taken at 4 degrees C would seem to predict that the linkage is impossible, because the span of the crosslinking agent is much less than the interthiol distance. The simplest resolution of this seeming paradox is that structural fluctuations of the protein render the linkage increasingly likely as the temperature increases. Also, measurements of the affinity of MgADP for the protein, as well as the magnetic resonance of the P-atoms of the ADP once emplaced, suggest that binding the first reagent anchor to Cys-707 initiates an influence that travels to the rather distant ADP-binding site, and it is speculated what this "path of influence" might be.

Advantages of using nested collision induced dissociation/post-source decay with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry: sequencing of novel peptides from wasp venom

We have examined the applicability of the 'nested' collision induced dissociation/post-source decay (CID/PSD) method to the sequencing of novel peptides from solitary wasps which have neurotoxic venom for paralyzing other insects. The CID/PSD spectrum of a ladder peptide derived from an exopeptidase digest was compared with that of the intact peptide. The mass peaks observed only in the CID/PSD spectrum of a ladder peptide were extracted as C-terminal fragment ions. Assignment of C-terminal fragment ions enabled calculation of N-terminal fragment masses, leading to differentiation between N-terminal fragment ions and internal fragment ions. This methodology allowed rapid and sensitive identification by removing ambiguity in the assignment of the fragment ions, and proved useful for sequencing unknown peptides, in particular those available as natural products with a limited supply.

Efficient synthesis and biological evaluation of all A-ring diastereomers of 1alpha,25-dihydroxyvitamin D3 and its 20-epimer

An improved synthesis of the diastereomers of 1alpha,25-dihydroxyvitamin D3 (1) was accomplished utilizing our practical route to the A-ring synthon. We applied this procedure to synthesize for the first time all possible A-ring diastereomers of 20-epi-1alpha,25-dihydroxyvitamin D3 (2). Ten-step conversion of 1-(4-methoxyphenoxy)but-3-ene (6), including enantiomeric introduction of the C-3 hydroxyl group to the olefin by the Sharpless asymmetric dihydroxylation, provided all four possible stereoisomers of A-ring enynes (3). i.e., (3R,5R)-, (3R,5S)-, (3S,5R)- and (3S,5S)-bis[(tert-butyldimethylsilyl)oxy]oct-1-en-7-yne, in good overall yield. Palladium-catalyzed cross-coupling of the A-ring synthon with the 20-epi CD-ring portion (5), (E)-(20S)-de-A,B-8-(bromomethylene)cholestan-25-ol, followed by deprotection, afforded the requisite diastereomers of 20-epi-1alpha,25-dihydroxyvitamin D3 (2). The biological profiles of the synthesized stereoisomers were assessed in terms of affinities for vitamin D receptor (VDR) and vitamin D binding protein (DBP). HL-60 cell differentiation-inducing activity and in vivo calcium-regulating potency in comparison with the natural hormone.

Sonography of pneumatosis cystoides intestinalis

Pneumatosis cystoides intestinalis (PCI) is a relatively rare benign condition, and its sonographic findings have rarely been reported. We report on four cases of PCI in which sonography showed multiple immobile linear or spotty high echoes in the thickened colonic wall. These sonographic findings were more clearly visualized by using high-frequency probes and helped in establishing the diagnosis. In addition, color Doppler sonography confirmed the absence of portal gas and helped rule out fulminant PCI. When encountering patients with abundant abdominal gas, the possibility of PCI should be considered and the colonic wall and the portal vein should be meticulously observed by high-frequency probe and color Doppler sonography to prevent a delay in the diagnosis and to improve patient management.

Portal tumor thrombus due to gastrointestinal cancer

METHODS

We studied the clinical data of seven patients with portal tumor thrombus (PTT) due to gastrointestinal (GI) cancer to determine the radiologic patterns and clinical implications of this rare complication.

RESULTS

(a) PTT was located along the entire splenic vein in three cases, at the splenomesenteric confluence in one case, and in the superior mesenteric vein in one case. Intrahepatic PTT occurred in two of four cases with liver metastasis. (b) One cirrhotic case was complicated by the occurrence of colon cancer associated with PTT in the splenic vein; the esophageal varices became rapidly enlarged and poorly controlled, and the patient died due to repeated variceal rupture. (c) In all patients, abdominal sonography (US) detected PTT and color Doppler sonography confirmed the US findings.

CONCLUSIONS

The splenic vein should be meticulously observed by color Doppler sonography to check for PTT in patients with GI cancer to improve patient care.

Characterization of human immunodeficiency virus type 1 strains resistant to the non-nucleoside reverse transcriptase inhibitor RD4-2217

The non-nucleoside reverse transcriptase (RT) inhibitor RD4-2217 is a thiadiazole derivative that has proved to be a highly potent and selective inhibitor of human immunodeficiency virus type 1 (HIV-1) replication in vitro. In this study we examined genotypic and phenotypic characteristics of RD4-2217-resistant mutants that have been obtained by serial passage of HIV-1 in MT-4 cells in the presence of increasing concentrations (0.05, 0.25, 1 and 10 microM) of the compound. The strains obtained, III(B/2217RE/0.05) and III(B/2217RE/0.25,) were two- and 15-fold resistant to RD4-2217, respectively, whereas III(B/2217RE/1) and III(B/2217RE/10) displayed 161- and >238-fold resistance, respectively. Both III(B/2217RE/1) and III(B/2217RE/10) had two amino acid substitutions, V1891 and T2401, in the RT. Furthermore, RD4-2217 did not inhibit the replication of an HIV-1 molecular clone, which had the same mutation, at concentrations up to 10 microM, indicating that the V1891 plus T2401 mutation confers high-level resistance to RD4-2217. Interestingly, the replicability of III(B2217RE/1) and III(B/2217RE/10) appeared to be lower than that of wildtype III(B) in MT-4 cells, suggesting that the V1891 plus T2401 mutation may impair the enzymatic activity of HIV-1 RT.

Unusual late extrapulmonary metastasis in osteosarcoma

The major site of metastasis from osteosarcoma is the lung, and over 90% of fatalities in patients with this disease die from pulmonary metastases. Extrapulmonary disease is developing in an increasing proportion of patients, usually after pulmonary metastasis. This study reports three cases of patients with osteosarcoma that metastasized to the brain, mediastinum, intramuscular site, and pelvic cavity. The physician must be aware that extrapulmonary metastases may be present at the time a pulmonary metastasis becomes evident.

Acridone derivatives are selective inhibitors of HIV-1 replication in chronically infected cells

In our extensive screening of anti-HIV-1 agents in chronically infected cell lines, we have found acridone derivatives to be selective inhibitors of HIV-1 replication. Among the acridone derivatives, 1-hydroxy-10-methyl-9,10-dihydroacrid-9-one (RD6-5071) suppressed tumor necrosis factor (TNF)-alpha-induced HIV-1 expression in the latently infected cell line OM-10.1, U1, and ACH-2. Its 50% effective concentration for HIV-1 p24 antigen production was 2.0 microg/ml in OM-10.1 cells, while its 50% cytotoxic concentration was 18 microg/ml. The compound also inhibited phorbol 12-myristate 13-acetate (PMA)-induced HIV-1 expression in these cell lines. Furthermore, RD6-5071 was inhibitory to HIV-1 replication in acutely infected U937 and peripheral blood mononuclear cells. The compound was found to suppress TNF-alpha-induced HIV-1 long terminal repeat-driven gene expression. An inhibition assay for protein kinase C (PKC) revealed that RD6-5071 could reduce the enzyme activity. Furthermore, the compound was a moderate inhibitor of PMA-induced nuclear factor kappaB (NF-kappaB) activation, as determined by a gel mobility shift analysis. These results suggest that the acridone derivatives suppress HIV-1 replication at the transcriptional level primarily through a mechanism of PKC inhibition.

Multinodular fatty change in the liver in patients with chronic hepatic porphyria

We present five cases of chronic hepatic porphyria (CHP) without skin lesions, in whom a multinodular fatty change in the liver was incidentally detected by ultrasound. Discovery prompted further examinations, leading to the diagnosis of CHP. Although relatively rare, the possibility of CHP must be considered when encountering patients with irregular (multinodular) fatty infiltration of the liver of unknown cause. We also discuss the differential diagnosis.

Species differences in the transport activity for organic anions across the bile canalicular membrane

Species differences in the transport activity mediated by canalicular multispecific organic anion transporter (cMOAT) were examined using temocaprilat, an angiotensin-converting enzyme inhibitor whose biliary excretion is mediated predominantly by cMOAT, and 2,4-dinitrophenyl-S-glutathione, a typical substrate for cMOAT, in a series of in vivo and in vitro experiments. Temocaprilat was infused to examine the biliary excretion rate at steady-state. The in vivo transport clearance values across the bile canalicular membrane, defined as the biliary excretion rate divided by the hepatic unbound concentrations, were 9.8, 39.2, 9.2, 1.1, and 0.8 ml/min/kg for mouse, rat, guinea pig, rabbit, and dog, respectively. The K(m) and V(max) values for ATP-dependent uptake of 2, 4-dinitrophenyl-S-glutathione into canalicular membrane vesicles were 15.0, 29.6, 16.1, 55.8, and 30.0 microM and 0.38, 1.90, 0.15, 0. 47, and 0.23 nmol/min/mg protein, yielding the in vitro transport clearance across the bile canalicular membrane (V(max)/K(m)) of 25.5, 64.2, 9.4, 8.4, and 7.7 for mouse, rat, guinea pig, rabbit, and dog, respectively. A close in vivo and in vitro correlation was observed among animal species for the transport clearance across the bile canalicular membrane. These results suggest that the uptake experiments with canalicular membrane vesicles can be used to quantitatively predict in vivo excretion across the bile canalicular membrane.

Enzymatic activation of oleuropein: a protein crosslinker used as a chemical defense in the privet tree

Leaves of the privet tree, Ligustrum obtusifolium, contain a large amount of oleuropein, a phenolic secoiridoid glycoside, which is stably kept in a compartment separate from activating enzymes. When the leaf tissue is destroyed by herbivores, enzymes localized in organelles start to activate oleuropein into a very strong protein denaturant that has protein-crosslinking and lysine-decreasing activities. These activities are stronger than ever reported from plant systems and have adverse effects against herbivores by decreasing the nutritive value of dietary protein completely. We report here that strong oleuropein-specific beta-glucosidase in organelles activates oleuropein by converting the secoiridoid glucoside moiety of oleuropein into a glutaraldehyde-like structure, which is also an alpha,beta-unsaturated aldehyde. Oleuropein activated by beta-glucosidase had very strong protein-denaturing, protein-crosslinking, and lysine-alkylating activities that are very similar to, but stronger than, those of glutaraldehyde. Aucubin, another iridoid glycoside, had similar activities after beta-glucosidase treatment. We also detected polyphenol oxidase activity in organelles that activate the dihydroxyphenolic moiety to have protein-crosslinking activities. These data suggest that the privet tree has developed an effective defense mechanism with oleuropein, a unique multivalent alkylator ideal as a protein-crosslinker. Our results that iridoid glycosides are precursors of alkylators may elucidate the chemical bases that underlie various bioactivities and ecological roles of iridoid glycosides.

Preparation of specific antisera to 15alpha-hydroxyestrogens

The synthesis of haptens of 15alpha-hydroxyestrone, 15alpha-hydroxyestradiol, and 15alpha-hydroxyestriol (estetrol) was undertaken, to obtain specific antisera required for enzyme immunoassay. 3-(1-Carboxypropyl) ethers of these 15alpha-hydroxyestrogens were prepared and conjugated with bovine serum albumin and horseradish peroxidase. The specificity of antisera elicited against bovine serum albumin conjugates was checked by the enzyme immunoassay by using horseradish peroxidase-labeled antigen, and proved to be satisfactory in terms of cross-reactivities to related compounds.

[Combined multimodal therapy for osteosarcoma--neoadjuvant chemotherapy]

Until the 1970s, the survival rate of osteosarcoma patients was less than 20%. By the 1990s, this had improved to 60% to 70%, and limb-sparing procedures have replaced amputation in many patients thanks to effective combination therapy. Neoadjuvant chemotherapy has become an accepted practice in the majority of institutions using protocols which include MTX, ADR, BCD and CDDP as the most active agents against this disease. Newer agents, particularly IFM and ETP, are increasingly incorporated into complex regimens. While several studies have reported multivariate analyses to identify prognostic factors, the histologic response to preoperative chemotherapy remains the most important prognostic factor. Pulmonary metastases are the primary cause of death in patients with osteosarcoma. Although current treatment regimens allow effective salvage therapy for the patients with pulmonary metastases, the actuarial survival rate is 30%. A more effective systemic treatment for those patients is needed. The current management of osteosarcoma is critically reviewed and a treatment strategy is proposed for discussion.

Longstanding arterioportal fistula after laparoscopic liver biopsy

We present two patients with hepatocellular carcinoma (HCC) on liver cirrhosis in whom color Doppler sonography documented an incidental peripheral arterioportal fistula due to a previous liver biopsy under laparoscopy. Detection of the fistula helped in preventing the occurrence of a portal thrombus. Color Doppler sonography should be performed prior to transarterial embolization in patients with HCC on liver cirrhosis with a past history of liver biopsy under laparoscopy.

Splenic lymphangioma: US and CT diagnosis and clinical manifestations

BACKGROUND AND METHODS

We tried to determine the role and problems of gray-scale sonography (US), computed tomography (CT), and color Doppler sonography in the diagnosis of splenic lymphangioma on the basis of our experience with seven adult cases with this relatively rare tumor.

RESULTS

(1) The whole spleen was replaced by a collection of cysts of different sizes with or without calcifications in six patients. In these patients, color Doppler sonography showed the intrasplenic arteries and veins running along the cyst walls. (2) The enlarged spleen occupied the whole upper abdomen and contained numerous small cysts in one patient. The patient was initially diagnosed as having a pancreatic tumor because of the location, but color Doppler sonography clearly demonstrated two vessels (artery and vein) running parallel from the center of the mass. This characteristic vascular structure led to the determination that the mass was the markedly enlarged spleen. (3) The splenic lesion was isolated in six patients but was associated with mesenteric and pleural lymphangioma in one symptomatic patient.

CONCLUSIONS

(1) When US shows multiple cysts of different sizes in the spleen, the diagnosis of splenic lymphangioma is not difficult to make with US and CT alone. (2) Color Doppler sonography is a very useful tool to increase diagnostic confidence because it demonstrates the vasculature of the mass. (3) When examining patients with splenic lymphangioma, one should consider the possibility of multiorgan involvement.

Intussusception in Peutz-Jeghers syndrome: sonographic findings

An intussusception can easily occur in patients with Peutz-Jeghers syndrome (PJS), and its early detection is crucial. We present a PJS patient in whom sonography (US) helped in detecting intussusception at a time when there was only a very vague symptom and provided successful conservative treatment. Close clinical and US follow-up of PJS patients should improve management of this condition.

Color Doppler findings of tumor seeding after US-guided liver tumor biopsy

We present two cases with tumor seeding along the needle tract occurring after a large-core needle liver tumor biopsy performed at other hospitals. Color Doppler sonography showed the hypervascular nature of the lesion and increased diagnostic confidence.

Anti-herpesvirus activities and cytotoxicities of 2-thiopyrimidine nucleoside analogues in vitro

Twenty 2-thiopyrimidine nucleoside analogues were synthesized and examined for inhibitory activity against herpes simplex virus (HSV) type 1 and 2, varicella-zoster virus (VZV), human cytomegalovirus (HCMV) and thymidine kinase-deficient HSV (HSV-TK-) replication in vitro. 2-thiouracil (thymine) arabinoside, 2'-deoxy-2-thiouridine (or 2-thiothymidine) and their 5-halogenated derivatives showed anti-HSV activity in both RPM18226 (human B-lymphoblastoid cells) and MRC-5 (human embryo lung cells). 2'-deoxy-5-halogenated-2-thiocytidines were also inhibitory against HSV, whereas 2-thiocytosine arabinoside and its derivatives were not inhibitory against HSV replication, except 5-bromo and 5-iodo congeners (TN-31, TN-32). Substitution of the halogen atom at the 5-position of the pyrimidine rings to an atom with a higher molecular weight increased anti-HSV and VZV activities, except for the anti-HSV activity of 2-thiouracil arabinosides. 2'-deoxy-5-methyl-, and 2'-deoxy-5-iodo-2-thiouridines (TN-17, TN-44) showed the most potent anti-HSV activity, and 2'-deoxy-5-chloro- and 2'-deoxy-5-bromo-2-thiocytidines were potent inhibitors of VZV replication. However, none of the compounds inhibited HCMV and HSV-TK- replication. TN-31 and TN-32 were shown to inhibited HCMV and HSV-TK- as well as HSV and VZV replication. The cytotoxicity of the 2-thio-pyrimidine nucleoside analogues was less than that of the 2-oxy-congeners of the compounds (5-iodo-2'-deoxyuridine, 5-iodo-2'-deoxycytidine, thymine arabinoside and cytosine arabinoside). The selectivity index of 2'-deoxy-5-iodo-2-thiouridine (TN-44) was higher than that of 5-iodo-deoxyuridine. TN-17 and TN-44 were not cytotoxic to resting or stimulated human peripheral blood mononuclear cells at 400 microM, although TN-32 was cytotoxic at a concentration of 20 microM.

Gastrointestinal bleeding due to ruptured pseudoaneurysm in patients with pancreatitis

We present the medical imaging results and clinical data of four pancreatitis cases with gastrointestinal bleeding due to rupture of a pseudoaneurysm to determine in which situations a rupture should be suspected. Our observations suggest that the possibility of such a rupture must be kept in mind when encountering not only patients with hematemesis or melena associated with acute severe abdominal symptoms but also patients with severe anemia. Color Doppler sonography and computed tomography are very useful as first-line diagnostic tools and should be performed promptly to prevent a delay in patient management.

Hyperplasia of gastric mucosa in donor rats orally infected with Taenia taeniaeformis eggs and in recipient rats surgically implanted with the larvae in the abdominal cavity

Rats heavily infected with Taenia taeniaeformis larvae in the liver show a remarkable increase in their stomach weight, hyperplasia, and hypergastrinemia. However, it is unknown what causes these phenomena. Hence, as a preliminary study to investigate the importance of larval parasitism in the liver, two experiments were done. In the first experiment, 14 donor rats were orally inoculated with 3,000 T. taeniaeformis eggs. In the second experiment, 136-300 of the larvae obtained from the rats were surgically implanted into the abdominal cavity of 7 recipient rats. Gastrin levels and histopathological changes in the gastric mucosa were investigated. In all, 11 donor rats showed hypergastrinemia and hyperplasia, 5 recipient rats showed gastric mucosal hyperplasia accompanied by excessive mucous cell proliferation, and 2 recipient rats showed hypergastrinemia. These results suggest that parasitism of the liver by the larvae is not essential for the development of hyperplasia and that factors from the larvae might cause these phenomena.

Improved and efficient synthesis of 1alpha-hydroxy-[6-(2)H] and 1alpha-hydroxy-[6,19,19-(2)H]vitamin D3 derivatives

Improved and efficient procedures for deuterium-labeling at the 6,19,19 positions of 1alpha-hydroxyvitamin D3 derivatives via its sulfur dioxide-adduct by using a base-catalyzed H-D exchange reaction are described. Application of the known procedure using tBuOK/DMF-D2O, which is effective for labeling vitamin D3 derivatives, to 1alpha-hydroxy compounds gave only poor results because of isomerization and decomposition. We found that this procedure is improved by the use of iPrONa/iPrOD. During this study, we also found that the 6-monodeuterated product was selectively obtained when MeONa/CD3OD was employed instead of iPrONa/iPrOD. On the other hand, simple addition of 1,3-dimethyl-2-imidazolidinone as a co-solvent to the above conditions was effective for 1alpha,25-dihydroxy compounds. These improved procedures were successfully applied to the synthesis of 1alpha-hydroxy-[6,19,19-(2)H]vitamin D3 derivatives 4 and 1alpha-hydroxy-[6-(2)H]vitamin D3 derivatives 6 from the corresponding 1alpha-hydroxyvitamin D3 derivatives 1 via its sulfur dioxide-adducts 2, 3 and 5 in good over-all yield with high deuterium incorporation.

Assessment of resectability of pancreatic carcinoma by color Doppler sonography

This study was undertaken to evaluate the role of color Doppler sonography in the preoperative assessment of vascular involvement in patients with pancreatic carcinoma. Twenty-six pancreatic carcinomas were investigated with color Doppler sonography and angiography, and the results of these examinations were compared with those of surgical findings. Color Doppler sonography was more sensitive than angiography in depicting vascular involvement of carcinoma. Thus, it seems rational to perform a preoperative assessment in suspected pancreatic carcinoma patients initially with color Doppler sonography to improve patient management.

Color Doppler sonography of the gastroepiploic vein

The gastroepiploic vein (GEV) may serve as a collateral circulation associated with splenic vein thrombosis. Despite the extensive literature on its computed tomographic and angiographic findings, there is no description of color Doppler findings of the GEV. We report scanning techniques for observing its entire course. When examining patients with pancreatic disease, familiarity with these color Doppler findings could help in the detection of not only splenic vein thrombus but also the GEV and may contribute to patient management.

Mouse model of respiratory syncytial virus infection to evaluate antiviral activity in vivo

In this study, we have developed a practical mouse model for evaluating in vivo the antiviral activity of compounds against respiratory syncytial virus (RSV) infection. BALB/c mice are not particularly susceptible to RSV infection; however, infection rates were improved by pretreatment with the immunosuppressive agent cyclophosphamide (CYP). When mice were inoculated intranasally with RSV A2 strain, the pulmonary RSV titres of CYP-pretreated 10-week-old mice were higher than those of untreated 10-week-old and 28-week-old mice, peaking on days 4 and 5 post-infection. Sections of lung from RSV-infected mice pretreated with CYP, taken on day 4 post-inoculation, showed widespread evidence of interstitial pneumonia and other significant pathological changes. We also confirmed that ribavirin, a representative antiviral agent, significantly reduced the pulmonary RSV titres of mice pretreated with CYP when administered intraperitoneally.

Histopathology and physiopathology of gastric mucous hyperplasia in rats heavily infected with Taenia taeniaeformis

Rats heavily infected with larval Taenia taeniaeformis show hyperplasia of the gastric mucosa accompanied by mucous cell proliferation, increase in the level of intragastric pH and hypergastrinemia. Sixty one rats were divided into 2 groups designed as infected (36 rats) and control (25 rats) group. These rats were examined with time course of the infection histopathologically and physiopathologically, during 14-112 days postinfection (DPI). In the infected rats, gastric mucosal hyperplasia began to be observed at 56 DPI, and the structural disturbance of zymogenic units in the corpus and mucous units in the antrum had increased with time. However, the degree of these changes in the antrum was weaker than those in the corpus. Alcianblue and/or PAS-positive cells increased in their numbers with time, and 4 types of cells other than typical surface mucous cell and mucous neck cell were observed by electron-microscopy. However, zymogenic and parietal cells decreased in their number after 56 DPI. Further, the infected rats showed changes in the serum concentration of alanine aminotransferase, aspartate aminotransferase, blood urea nitrogen, glucose and total protein. Some similarities with Menetrier's disease were discussed.

Efficacy of RD3-0028 aerosol treatment against respiratory syncytial virus infection in immunosuppressed mice

RD3-0028, a benzodithiin compound, has antiviral activity against respiratory syncytial virus (RSV) in cell culture. We used a mouse model of RSV infection to determine the in vivo effect of RD3-0028. Cyclophosphamide (CYP)-treated, immunosuppressed mice were inoculated intranasally. The lungs of the mice were removed on day 4. The virus titers of the lungs of RD3-0028-treated mice were compared to the virus titers of the lungs of virus-inoculated, untreated control mice. In an effort to increase the therapeutic effectiveness of this compound, RD3-0028 was administered by aerosol to RSV-infected mice by using a head-exposure system. Aerosols generated from reservoirs containing RD3-0028 (7 mg/ml) administered for 2 h twice daily for 3 days significantly reduced the pulmonary titer of RSV-infected mice. It is clear that the minimal effective dose of RD3-0028 for RSV-infected mice is significantly less than that of ribavirin, the only compound currently available for use against RSV disease. Furthermore, the RD3-0028 aerosol administration appeared to protect the lungs of infected, CYP-treated mice against tissue damage, as evidenced by the preservation of the lung architecture and a reduction in pulmonary inflammatory infiltrates. RD3-0028 aerosol was not toxic for mice at the therapeutic dose. The present study demonstrates the effectiveness of aerosol administration of RD3-0028 for RSV-infected mice.

Inhibition of human immunodeficiency virus replication by RD6-Y664, a novel benzylhydroxylamine derivative

We have examined novel benzylhydroxylamine derivatives for their inhibitory effects on the replication of human immunodeficiency virus (HIV) in cell cultures. Among the series, O-(2-chloro-6-fluorobenzyl)hydroxylamine (RD6-Y664) was found to be the most potent inhibitor of HIV-1. The EC50 for HIV-1 strain IIIB was 1.6 micrograms/ml with a selectivity index greater than 38 in MT-4 cells. It also inhibited the replication of other HIV strains including a non-nucleoside reverse transcriptase (RT) inhibitor-resistant mutant, a nucleoside RT inhibitor-resistant mutant and HIV-2, in acutely infected cells. However, the compound did not affect HIV-1 production in chronically infected cells. A time-of-addition experiment and detection of proviral DNA synthesis suggested that RD6-Y664 targeted an early step of the viral replication cycle, presumably a process prior to reverse transcription. In fact, an assay for HIV-1 RT revealed that the compound did not suppress enzyme activity. Furthermore, RD6-Y664 did not show any inhibition of gp120-CD4 interaction, or binding of anti-CXCR4 antibody to CXCR4.

Primary leiomyosarcoma of the greater omentum

We report a case of primary greater omental leiomyosarcoma successfully resected by omentectomy. Palpation of a painless abdominal mass at physical examination motivated medical imaging examination. Ultrasound visualized accurately the internal structure of the lesion but failed to determine the site of origin. Computed tomography and angiography determined the greater omental origin of the tumor before surgery. A review of the literature is also presented.

Hepatic hemangioma with arterioportal shunts

Color Doppler sonograms and angiographic findings in 23 hepatic hemangioma patients were compared to clarify how arterioportal shunts influence color Doppler findings of hepatic hemangiomas. The results of our study showed that the presence of arterioportal shunts (six cases) gave rise to large feeding arteries (five cases), multiple intratumoral flows (six cases), and reversal of portal flow within (five cases) or around (four cases) the tumor. These color Doppler findings mimicked hypervascular malignant tumors. Knowledge of such unusual color Doppler findings in hepatic hemangiomas may help in avoiding misinterpretations of color Doppler sonograms.

Upregulation of HIV-1 replication in chronically infected cells by ingenol derivatives

We have previously reported that ingenol derivatives are highly potent inhibitors of human immunodeficiency virus type 1 (HIV-1) replication in acutely infected cells. In this study, however, we have found that some ingenol derivatives strongly enhance the replication of HIV-1 in chronically infected cells at nanomolar concentrations. One of the derivatives could activate nuclear factor kappa B (NF-kappa B), a potent inducer of HIV-1 replication, through the activation of protein kinase C (PKC). Whereas another derivative, which affected neither PKC nor NF-kappa B, significantly enhanced HIV-1 replication, suggesting that a PKC-independent mechanism may also exist in ingenol derivative-induced HIV-1 upregulation.

Synthesis and biological evaluation of (23R)- and (23S)-24,24-difluoro-1 alpha,23,25-trihydroxyvitamin D3

The syntheses and biological evaluations of (23R)- and (23S)-24,24-difluoro-1 alpha,23,25-trithydroxyvitamin D3 (3a and 3b), new C-24 fluorinated analogs of 1 alpha,25-dihydroxyvitamin D3, are described. The syntheses of these compounds were achieved in 3 steps from (5Z,7E,20R)-1 alpha,3 beta-bis-[(tert-butyldimethylsilyl)oxy]-20-formylmethyl-9,10-seco- 5,7,10(19) pregnatriene (5) which is derived from vitamin D2. The absolute configuration at the C-23 position of 3a and 3b was determined by the modified Mosher method. The relative affinities of 3a and 3b to the vitamin D receptor were both 10 and 14 times lower than that of 1 alpha,25-dihydroxyvitamin D3 (1), and to vitamin D binding protein were also both 130 and 40 times lower. The HL-60 cell differentiating activity of 3a was 6 times more potent than that of 1, while there was no remarkable difference in activity between 3b and 1.