Involvement of 5-hydroxytryptamine neuronal system in Delta(9)-tetrahydrocannabinol-induced impairment of spatial memory

The present study investigated the involvement of the serotonin (5-hydroxytryptamine, 5-HT) neuronal system in the Delta(9)-tetrahydrocannabinol-induced impairment of spatial memory in the eight-arm radial maze in rats. Delta(9)-Tetrahydrocannabinol (6 mg/kg, i.p.), which impairs spatial memory, significantly increased the 5-HT content in the ventral hippocampus. A microdialysis study showed that Delta(9)-tetrahydrocannabinol (6 mg/kg, i.p.) decreased 5-HT release in the ventral hippocampus. The 5-HT precursor, 5-hydroxy-L-tryptophan (5-HTP; 50 mg/kg, i.p.), the 5-HT re-uptake inhibitor, clomipramine (0.01 and 0.1 mg/kg, i.p.), the 5-HT receptor agonist, 5-methoxy-N,N-dimethyltryptamine (5-MeODMT; 0.01 and 0.03 mg/kg, i.p.), and the 5-HT(2) receptor agonist, 1-(2,5-dimethoxy 4-iodophenyl)-2-amino propane (DOI; 10 microg/kg, i.p.), significantly attenuated the Delta(9)-tetrahydrocannabinol-induced impairment of spatial memory. These results suggest that the 5-HT neuronal system may be involved in the Delta(9)-tetrahydrocannabinol-induced impairment of spatial memory.

Accessory hepatic duct: sonographic findings

Accessory hepatic ducts are relatively rare biliary anomalies. They have been reported only sporadically, and very few reports have described their sonographic (US) findings. Our experience with two such cases suggested that a diagnosis of an accessory hepatic duct should be considered when US shows a fine tubular structure or an anechoic or hypoechoic oval mass with acoustic shadowing at the level between the hepatic hilus and the common bile duct. A good knowledge of the US findings will determine the diagnostic and therapeutic strategies.

Mesenteric lipoma: report of a case with emphasis on US findings

Mesenteric lipoma (ML) is a relatively rare disease that has been very infrequently reported. We present the clinical data and medical imaging results of an asymptomatic case with ML incidentally detected by sonography (US). On US the lesion was imaged as a well-demarcated hypoechoic mass with multiple linear echoes. The mass also changed location under probe compression. The lesion was imaged as a clearly demarcated non-enhanced homogeneous fat-density mass on CT. Color Doppler US and angiography confirmed the avascular nature of the mass. Knowledge of the US findings in this case is useful for the diagnosis of ML.

Increased serotonin release in mice frontal cortex and hippocampus induced by acute physiological stressors

The effects of acute physiological stressors (5 s tail pinch, handling and forced swimming at +25 and +5 degrees C for 3 min each) on serotonin (5-HT) release in the mouse brain were investigated using in vivo microdialysis. The extracellular 5-HT levels were determined by a newly developed highly-sensitive and selective high-performance liquid chromatography method based on derivatization with benzylamine and fluorescence detection. The basal levels of 5-HT in 3 min microdialysates from the ventral hippocampus and frontal cortex were 0.68+/-0.21 and 0.75+/-0.28 fmol/6 microl (n=24), respectively. All three stressors caused an immediate, significant and reversible increase (handling: 150%; swimming: 240%) of extracellular 5-HT levels in both brain structures, suggesting a more dynamic role played by the serotonergic system in response to acute stress.

Emphysematous cholecystitis: sonographic findings

BACKGROUND

Emphysematous cholecystitis (EC) is a rare but life-threatening complication of acute cholecystitis, and an early diagnosis is required to prevent delay in patient management. Because sonography (US) is the first choice for diagnosing gallbladder diseases, US findings of EC should be understood more precisely.

METHODS

We reviewed US findings of 11 surgically proven cases of EC (with small amounts of gas in three cases and large amounts in eight cases) and compared those with patients' clinical data.

RESULTS

(1) In cases with small amounts of gas, US showed an echogenic line with a distinct ring-down artifact or a "powder snow-like" speckled posterior echo. (2) In cases with large amounts of gas, US showed a wide spiculated echogenic band with a powder snow-like speckled posterior echo or a speckled acoustic shadowing. In all cases, the presence of gas prevented visualization of the gallbladder wall. (3) US did not differentiate gas localized to the gallbladder wall and gas extending to the surrounding hepatic tissue. (4) Two diabetic cases showed gas throughout the intrahepatic bile ducts. In those cases, the time from diagnosis to recovery was relatively long.

CONCLUSION

Our series showed some characteristic US patterns of EC. A good understanding of its US findings and appropriate emergent management will reduce the serious morbidity and mortality rates caused by EC.

Segmental chronic cholecystitis: sonographic findings and clinical manifestations

BACKGROUND

In chronic cholecystitis, the gallbladder (GB) wall is usually evenly involved, whereas marked segmental thickening of the GB wall (segmental cholecystitis) seldom is reported. We wanted to define its clinical manifestations and sonographic (US) findings.

METHODS

We reviewed the clinical and US data of 13 cases and compared these results with those of 30 patients with chronic cholecystitis with evenly thickened GB walls (usual-cholecystitis group).

RESULTS

(a) All cases of segmental cholecystitis showed the portion distal to the kinking to be markedly thickened. (b) The thickened portion corresponded to the fundus in three cases, the body and fundus in seven cases, and the fundus, body, and infundibulum in three cases; and the thickened distal portion contained many stones in 11 cases. (c) There was no difference in the maximal diameters of the GB walls between the segmental-cholecystitis group and the usual-cholecystitis group. However, there was a significant difference in the minimal diameters of the GB walls between groups.

CONCLUSION

Knowledge of the US findings and clinical presentations of segmental cholecystitis can help in the development of appropriate diagnostic and therapeutic strategies.

Renal arteriovenous malformation: sonographic findings

BACKGROUND AND METHODS

Renal arteriovenous malformation (RAVM) is a relatively rare congenital disease. Although sonography (US) currently is the first diagnostic tool for examining the kidney, its US and color Doppler findings have seldom been reported. We reviewed the clinical manifestations and US results of five cases of RAVM to clarify the role and limitations of US in the diagnosis.

RESULTS

The lesions were solitary in all cases, and the affected side was the right in four cases and the left in one case. In four cases, the patients complained of hematuria, but the remaining case had no symptoms. US did not detect the lesion, but in all cases color Doppler US showed a focal vascular lesion with posterior color spots. US reexamination with knowledge of the Doppler results did not show any focal lesion.

CONCLUSION

US was not diagnostic for RAVM, and color Doppler US should be performed immediately in patients with hematuria.

Localized gallbladder carcinoma: sonographic findings

Our study of color (seven cases) and contrast (three cases) Doppler results of seven cases with gallbladder carcinoma localized in the gallbladder wall (TNM stage T1) showed that the presence or absence of blood flow signals distinguishes gallbladder carcinoma in stage T1b (muscular involvement) from tumefactive biliary sludge and that injection of contrast medium markedly increased diagnostic confidence. Thus, when color Doppler sonography is ambiguous, contrast-enhanced Doppler sonography is the next line of investigation. However, actual color Doppler sonography is still not fully capable of displaying fine blood flow signals from gallbladder carcinoma in stage T1a (mucosal involvement), and greater Doppler sensitivity is mandatory for this purpose.

Duodenal carcinoma: sonographic findings

BACKGROUND

Duodenal carcinoma is a relatively rare tumor and its sonographic (US) findings have rarely been reported.

METHODS

We reviewed the clinical data and US results of 15 patients with histologically proven duodenal carcinoma to pinpoint the contribution of US to the diagnosis.

RESULTS

US was useful for not only detecting the duodenal carcinoma (13 of 15, 86.7%), which altered the endoscopic procedure in nine patients, but also for evaluating vascular involvement (marked portal invasion in four cases and inferior vena cava invasion in two cases). Four of the eight carcinomas arising from the second or third portion showed this vascular invasion.

CONCLUSION

After reviewing the clinical data and US results of 15 cases of duodenal carcinoma, we found that US was useful for detecting duodenal carcinoma and determining vascular invasion. Thus, US contributed significantly to alter the endoscopic procedure and patient management.

Peripheral bone metastasis from hepatocellular carcinoma: sonographic findings

BACKGROUND AND METHODS

We reviewed medical and radiologic records of five patients with bone metastasis from hepatocellular carcinoma (HCC) to evaluate the role of sonography (US) in the diagnosis of this bone metastasis.

RESULTS

The metastatic lesions were clearly visualized by US as expansive, homogeneous, soft tissue masses with bony destruction, and color Doppler US showed fine vessels within the lesions. After treatment, US showed a decrease in tumor size with an increase in echogenicity and a decrease in blood flow. Hepatic US at the time of bone metastasis showed a portal tumor thrombus in all cases.

CONCLUSION

When US detects a portal venous tumor thrombus in HCC patients, attention should be directed not only to the liver but also to bone to improve patient care. US is useful not only in detecting the metastatic lesion but also in evaluating the treatment effect.

Splenic lymphoma: differentiation from splenic cyst with ultrasonography

BACKGROUND AND METHODS

Lymphoma can be nearly anechoic and mimic a cyst on ultrasonography (US). To investigate whether this phenomenon occurs at the level of the spleen, we analyzed the US findings of 38 cases of splenic lymphoma and 16 cases of splenic cyst.

RESULTS

(1) With regard to shape, echogenicity of the lesion, and mode of posterior echo, there was no difference between splenic lymphomas and splenic cysts. However, the boundaries of the lesions were indistinct in splenic lymphomas and distinct in splenic cysts. (2) Blood flow signals and vascular penetration were seen exclusively in splenic lymphomas.

CONCLUSION

The mode of boundary echo (distinct or indistinct) distinguishes splenic lymphomas from splenic cysts. Color Doppler US increases the diagnostic confidence of US.

Liver tumors in fatty liver: difficulty in ultrasonographic interpretation

BACKGROUND

Fatty liver and liver tumors are very frequent diseases. Sonography (US) currently is the initial diagnostic tool for hepatic exploration. However, there is a marked paucity of US findings of tumors in fatty liver.

METHODS

We studied the US findings of 41 lesions (31 patients) with this combination, with special attention paid to internal echoes, marginal echoes, and especially the mode of back echoes, and compared them with the US results of 64 lesions (38 patients) without fatty liver.

RESULTS

Comparing the group having liver tumor without fatty liver with the group having liver tumor with fatty liver showed that (a) the number of hypoechoic lesions increased (29 of 41, 70.7%, vs. 16 of 64, 25.0.%), (2) the tumor margin appeared indistinct (32 of 41, 78.0%, vs. nine of 64, 14.1%), and (c) the lesions showing posterior echo enhancement increased (34 of 41, 82.9%, vs. eight of 64, 12.5%).

CONCLUSION

Liver tumors in fatty liver are expected to show unusual patterns on US, so we should consider this difficulty when interpreting these US findings and we should not make a conclusion without including other imaging modalities.

Determination of serotonin in microdialysis samples from rat brain by microbore column liquid chromatography with post-column derivatization and fluorescence detection

The present paper describes a new method for on-line determination of 5-HT in brain microdialysates from awake rats by microbore column liquid chromatography with post-column derivatization and fluorescence detection. The derivatization reagent contained 1 mM benzylamine and 0.5 mM potassium hexacyanoferrate (III), both dissolved in a mixture of acetonitrile and 25 mM borate buffer (pH 11.0) (1:1, v/v). The limit of detection (S/N=3) for 5-HT was 0.5 fmol/20 microl. The samples were injected every 20 min onto a microbore column packed with C18 silica gel. The method exhibits an excellent stability over the periods of at least 12-24 h. The basal levels of 5-HT from 25 awake rats were 7.10+/-1.06 fmol/20 microl in the dorsal hippocampus and 4.64+/-0.91 fmol/20 microl (mean+/-SD) in the striatum. The 5-HT release increased to about 1500% during the perfusion with 100 mM K(+) containing Ringer solution or it was reduced to 60 or 40% during the perfusion with 1 microM tetrodotoxin or calcium free Ringer, respectively. The new method can be used to monitor extracellular 5-HT following acute systemic drug administration.

X-Ray Telescope Onboard Astro-E. II. Ground-Based X-Ray Characterization

X-ray characterization measurements of the x-ray telescope (XRT) onboard the Astro-E satellite were carried out at the Institute of Space and Astronautical Science (Japan) x-ray beam facility by means of a raster scan with a narrow x-ray pencil beam. The on-axis half-power diameter (HPD) was evaluated to be 1.8?-2.2?, irrespective of the x-ray energy. The on-axis effective areas of the XRTs for x-ray imaging spectrometers (XISs) were approximately 440, 320, 240, and 170 cm(2) at energies of 1.49, 4.51, 8.04, and 9.44 keV, respectively. Those of the x-ray spectrometer (XRS) were larger by 5-10%. The replication method introduced for reflector production significantly improved the imaging capability of the Advanced Satellite for Cosmology and Astrophyics (ASCA) XRT, whose HPD is ~3.6?. The increase in the effective area by a factor of 1.5-2.5, depending upon the x-ray energy, compared with that of the ASCA, was brought about by mechanical scale up and longer focal lengths. The off-axis HPDs were almost the same as those obtained on the optical axis. The field of view is defined as the off-axis angle at which the effective area becomes half of the on-axis value. The diameter of the field of view was ~19? at 1.49 keV, decreasing with increasing x-ray energy, and became ~13? at 9.44 keV. The intensity of stray light and the distribution of this kind of light on the focal plane were measured at the large off-axis angles 30? and 60?. In the entire XIS field of view (25.4 mm x 25.4 mm), the intensity of the stray light caused by a pointlike x-ray source became at most 1% of the same pointlike source that was on the optical axis.

Mycotic abdominal aneurysm: report of a case with emphasis on the presence of gas echoes

Mycotic abdominal aneurysm is a relatively rare disease and its sonographic (US) findings have rarely been reported. We present a case of mycotic aneurysm of the common iliac artery in which the initial US showed a slightly wall-thickened abdominal aorta with gas echoes in the wall, a second US 6 days later showed a rapid increase in aortic size, and an emergent surgical intervention showed a mycotic aneurysm. This interesting observation suggested that the presence of gas echoes is a useful US finding indicating the beginning of a mycotic aneurysm and, when encountering this US finding, that emergent treatment should be considered to prevent delay in patient management.

Anti-AIDS agents. 46. Anti-HIV activity of harman, an anti-HIV principle from Symplocos setchuensis, and its derivatives

Matairesinol (1) and harman (5), identified from Symplocos setchuensis, were found to inhibit HIV replication in H9 lymphocyte cells. Anti-HIV evaluation of 28 derivatives of 5 revealed that compound 19 showed potent activity with EC(50) and therapeutic index values of 0.037 microM and 210, respectively.

Choledochal cyst due to anomalous pancreatobiliary junction in the adult: sonographic findings

BACKGROUND

Adult cases of choledochal cyst due to anomalous pancreaticobiliary duct junction have been rarely reported. At present, sonography (US) is the first tool for diagnosing biliary disorders. The aim of this study was to reevaluate the US findings of choledochal cysts due to anomalous pancreaticobiliary duct junction in adults.

METHODS

We reviewed the clinical manifestations and US findings of 12 such adult cases confirmed by endoscopic retrograde cholangiopancreatic ductography (ERCP). Patients were assigned to three groups: (a) associated with biliary carcinoma (two cases), (b) associated with choledocholithiasis (one case), and (c) not associated with other abdominal diseases (nine cases).

RESULTS

Patients in group c were asymptomatic, and the lesions were detected incidentally detected by US. In contrast, patients in group a sought medical care because of symptoms such as jaundice and those in group b sought medical attention because of abdominal pain. The diameter of a dilated bile duct on US was considerably less than that of ERCP (ERCP: 26-58 mm, mean = 37.6 mm; US: 13-32 mm, mean = 21.8 mm). Its diameter changed significantly under probe compression when the dilated bile duct took a purely cystic form but changed very little when it took a tubular form.

CONCLUSION

Unlike cases in children, adult cases of choledochal cyst are generally asymptomatic. Careful US observation of the bile duct is thus expected to detect asymptomatic adult choledochal cysts cases. Cyst diameter can change significantly under probe compression, so it is important not to compress the bile duct during routine US examination.

Macronodular deformity of the spleen

BACKGROUND AND METHODS

Macronodular splenic deformity without a focal lesion has rarely been reported. We present three such cases and discuss the possible pathomechanism.

RESULTS

There was one case of macronodular deformity of unknown cause. In this case, the liver was elongated anteriorly over the dome of the spleen, and the markedly deformed spleen mimicked a round lesion in the left lobe of the liver. Color Doppler ultrasonography showed the major intra- and perisplenic vessels to be patent. There were two cases of macronodular deformity associated with extended portal thrombosis. In both cases, portal thrombosis extended throughout the intrahepatic and extrahepatic portal systems, and this portal flow disturbance was presumed to be the cause of the splenic deformity.

CONCLUSION

Although very rare, thrombosis should be sought throughout the portal system when ultrasonography shows a markedly deformed spleen. Marked splenic deformity, especially in cases with an elongated liver, may mimic a liver tumor. A good understanding of its sonographic appearance may help sonographers prevent a hazardous misdiagnosis.

Characterization of RGS5 in regulation of G protein-coupled receptor signaling

RGS proteins (regulators of G protein signaling) serve as GTPase-activating proteins (GAPs) for G alpha subunits and negatively regulate G protein-coupled receptor signaling. In this study, we characterized biochemical properties of RGS5 and its N terminal (1-33)-deleted mutant (deltaN-RGS5). RGS5 bound to G alpha(i1), G alpha(i2), G alpha(i3), G alpha(o) and G alpha(q) but not to G alpha(s) and G alpha13 in the presence of GDP/AIF4-, and accelerated the catalytic rate of GTP hydrolysis of G alpha(i3) subunit. When expressed in 293T cells stably expressing angiotensin (Ang) AT1a receptors (AT1a-293T cells), RGS5 suppressed Ang II- and endothelin (ET)-1-induced intracellular Ca2+ transients. The effect of RGS5 was concentration-dependent, and the slope of the concentration-response relationship showed that a 10-fold increase in amounts of RGS5 induced about 20-25% reduction of the Ca2+ signaling. Furthermore, a comparison study of three sets of 293T cells with different expression levels of AT1a receptors showed that RGS5 inhibited Ang II-induced responses more effectively in 293T cells with the lower density of AT1a receptors, suggesting that the degree of inhibition by RGS proteins reflects the ratio of amounts of RGS proteins to those of activated G alpha subunits after receptor stimulation by agonists. When expressed in AT1a-293T cells, deltaN-RGS5 was localized almost exclusively in the cytosolic fraction, and exerted the inhibitory effects as potently as RGS5 which was present in both membrane and cytosolic fractions. Studies on relationship between subcellular localization and inhibitory effects of RGS5 and deltaN-RGS5 revealed that the N terminal (1-33) of RGS5 plays a role in targeting this protein to membranes, and that the N terminal region of RGS5 is not essential for exerting activities.

X-ray telescope onboard Astro-E: optical design and fabrication of thin foil mirrors

X-ray telescopes (XRT's) of nested thin foil mirrors are developed for Astro-E, the fifth Japanese x-ray astronomy satellite. Although the launch was not successful, the design concept, fabrication, and alignment procedure are summarized. The main purpose of the Astro-E XRT is to collect hard x rays up to 10 keV with high efficiency and to provide medium spatial resolution in limited weight and volume. Compared with the previous mission, Advanced Satellite for Cosmology and Astrophysics (ASCA), a slightly longer focal length of 4.5-4.75 m and a larger diameter of 40 cm yields an effective area of 1750 cm2 at 8 keV with five telescopes. The image quality is also improved to 2-arc min half-power diameter by introduction of a replication process. Platinum is used instead of gold for the reflectors of one of the five telescopes to enhance the high-energy response. The fabrication and alignment procedure is also summarized. Several methods for improvement are suggested for the reflight Astro-E II mission and for other future missions. Preflight calibration results will be described in a forthcoming second paper, and a detailed study of images will be presented in a third paper.

[Dynamic MR imaging of liver lesions with superparamagnetic iron oxide (SH-U-555A)]

Dynamic MRI with SH-U-555 (SPIO) was evaluated. Dynamic MRI was performed for 17 patients with 22 lesions. Dynamic study with T2*-weighted imaging (T2* dynamic) and T1-weighted imaging (T1 dynamic) were performed in 8 cases (10 lesions) and 9 cases (12 lesions), respectively. T2* dynamic MR images were obtained before and 30, 90, 180, 270, 360, and 450 seconds and 31 minutes after the intravenous injection of SPIO, and T1 dynamic MR images were obtained before and 0, 40, 80, 120, 180, 240, 300, 360, 420, and 480 seconds and 28 minutes after the injection of SPIO. The signal intensity of each lesion was measured before and after the injection of SPIO. The enhancement ratio of the lesions was calculated and evaluated. The enhancement ratio of hypervascular lesions decreased rapidly in the first phase of T2* dynamic MRI, while that of hypovascular lesions decreased gradually. The enhancement ratio of hypervascular lesions increased in the first phase of T1 dynamic MRI and decreased gradually, while that of hypovascular lesions lacked the increase in the first phase, in contrast to hypervascular lesions. However, the changing of signal intensity could not be recognized on images with T2* dynamic and T1 dynamic study. In conclusion, quantitative analysis using the enhancement ratio made it possible to anticipate lesion vascularity.

Pancreatic uncinate carcinoma: sonographic findings

BACKGROUND

Pancreatic carcinoma arising from the uncinate process (pancreatic uncinate carcinoma) is relatively rare. We wished to define its clinical manifestations and sonographic findings.

METHODS

Clinical and sonographic data of eight cases were reviewed.

RESULTS

The common bile duct and the pancreatic duct were not dilated until a very late stage. The lesion mimicked a mesenteric tumor in two cases. The superior mesenteric vessels were compressed anteriorly. Computed tomography was useful, not only for confirming the pancreatic uncinate origin of the lesion but also for determining precisely the mode of mesenteric vascular involvement.

CONCLUSION

Knowledge of these unusual sonographic findings can determine the diagnostic strategy in pancreatic uncinate carcinoma.

Pancreatic metastasis: sonographic findings

BACKGROUND

Pancreatic metastasis is a relatively rare pathologic condition. Its ultrasound (US) findings have been infrequently reported, and there has been no previous report describing its color Doppler findings.

METHODS

We reviewed the US findings of 13 such cases.

RESULTS

The pancreatic metastasis consisted of a single hypoechoic nodule in four cases and multiple hypoechoic nodules in nine cases. US showed a slight dilatation of the main pancreatic duct in two cases of pancreatitis, and a marked biliary dilatation in one case of jaundice. The US results prompted introduction of appropriate treatment in these cases. Color Doppler US was useful for confirming the absence of flow abnormalities in the arterial and portal systems around the pancreas. In a patients with renal carcinoma metastasis, it showed many fine blood flow signals in the metastatic lesions.

CONCLUSION

The role of US in the diagnosis of pancreatic metastasis consists of associated complications such as biliary dilatation or pancreatitis and detection of isolated lesions. Additional information provided by color Doppler US may increase diagnostic confidence.

Liquid chromatographic determination of ornithine and lysine based on intramolecular excimer-forming fluorescence derivatization

A highly sensitive and selective fluorometric determination method for ornithine and lysine has been developed. This method is based on an intramolecular excimer-forming fluorescence derivatization with a pyrene reagent, 4-(1-pyrene)butyric acid N-hydroxysuccinimide ester (PSE), followed by reversed-phase liquid chromatography (LC). The analytes, containing two amino moieties in a molecule, were converted to the corresponding dipyrene-labeled derivatives by reaction with PSE. The derivatives afforded intramolecular excimer fluorescence (450-550 nm) which can clearly be discriminated from the normal fluorescence (370-420 nm) emitted from PSE and monopyrene-labeled derivatives of monoamines. The structures of the derivatives and the emission of excimer fluorescence were confirmed by LC with mass spectrometry and with three-dimensional fluorescence detection system, respectively. The PSE derivatives of ornithine and lysine could be separated by reversed-phase LC on ODS column with isocratic elution. The detection limits (signal-to-noise ratio = 3) for ornithine and lysine were 3.5 and 3.7 fmol, respectively, for a 20-microl injection. Furthermore, this method had enough selectivity and sensitivity for the determination of ornithine and lysine in normal human urine.

Liver tumors in children and young patients: sonographic and color Doppler findings

BACKGROUND

Liver tumors are a relatively rare pathologic condition in children and young patients. The aim of the present study was to categorize the sonographic (US) and color Doppler results of liver tumors in these patients.

METHODS

We retrospectively reviewed the US findings of 23 such cases: malignant tumor (13 cases)-hepatoblastoma (four cases), hepatocellular carcinoma (HCC; four cases), and hepatic metastasis (five cases); benign tumor (10 cases)-hepatocellular adenoma (four cases), focal nodular hyperplasia (two cases), mesenchymal hamartoma (two cases), cystadenoma (one case), and hemangioendothelioma (one case).

RESULTS

There was no specific US findings for each tumor type. HCC usually developed on a normal liver and was imaged as multiple nodules. Color Doppler US helped in differentiating multiple metastatic nodules (hypovascular) from multiple HCC nodules (hypervascular). Presence of intratumoral cystic areas was usually suggestive of benign tumors. Follow-up US was useful for detecting small nodules in high-risk groups (congenital biliary atresia, glycogen storage disease). Color Doppler US helped in diagnosing portal thrombus or intratumoral shunt.

CONCLUSION

Although there were no highly specific findings, US and color Doppler results contributed, to a certain degree, to the diagnosis of liver tumors in children and young adults by showing intratumoral cystic areas or vascularity.

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.

Total reconstruction of the alar cartilages with a partially split septal cartilage graft

The alar cartilage is a unique structure that supports the tip of the nose, keeps the external valve open, and plays an important role in tip aesthetics. Very often the plastic surgeon needs to reconstruct this cartilage, as in secondary rhinoplasties when the lower lateral cartilage is overresected. Many authors have described cartilage grafts taken from the ear and septum, mounted and stitched in various manners, with some very good results. In patients with thin skin, though, any irregularity or distortion in the grafts becomes visible after a short time postoperatively. The authors present an alternative to reconstructing alar cartilage symmetrically using one graft. This graft is obtained by shaping septal cartilage in an "L" form, with a 135-deg angle (instead of a 90-deg angle) between its legs, and then splitting the smaller leg, obtaining a strut from the longer leg and two "lateral crura" from the shorter leg.

Antitumor-promoting effects of cyclic diarylheptanoids on Epstein-Barr virus activation and two-stage mouse skin carcinogenesis

Eleven cyclic diarylheptanoids were screened as potential antitumor promoters by examining the ability of the compounds to inhibit Epstein-Barr virus early antigen activation (induced by 12-O-tetradecanoylphorbol-13-acetate) in Raji cells. 13-Oxomyricanol and myricanone showed the highest activity and also exhibited remarkable inhibitory effects on mouse skin tumor promotion in an in vivo two-stage carcinogenesis test. These data suggest that certain diarylheptanoids might be valuable antitumor promoters and/or chemopreventors.

Highly selective fluorometric determination of polyamines based on intramolecular excimer-forming derivatization with a pyrene-labeling reagent

We introduce a novel approach in highly selective and sensitive fluorescence derivatization of polyamines. This method is based on an intramolecular excimer-forming fluorescence derivatization with a pyrene reagent, 4-(1-pyrene)butyric acid N-hydroxysuccinimide ester (PSE), followed by reversed-phase high-performance liquid chromatography (HPLC). Polyamines, having two to four amino moieties in a molecule, were converted to the corresponding dipyrene- to tetrapyrene-labeled derivatives by reaction (100 degrees C, 20 min) with PSE. The derivatives afforded intramolecular excimer fluorescence (450-520 nm), which can clearly be discriminated from the monomer (normal) fluorescence (360-420 nm) emitted from PSE, its hydrolysate and monopyrene-labeled derivatives of monoamines. The structures of the derivatives were confirmed by HPLC with mass spectrometry, and the emission of excimer fluorescence could be proved by spectrofluorometry and time-resolved fluorometry. The PSE derivatives of four polyamines [putrescine (Put), cadaverine (Cad), spermidine (Spd), and spermine (Spm)] could be separated by reversed-phase HPLC on a C8 column with linear gradient elution. The detection limits (signal-to-noise ratio of 3) for the polyamines were 1 (Put), 1 (Cad), 5 (Spd), and 8 (Spm) fmol on the column. Furthermore, the present method was so selective that biogenic monoamines gave no peak in the chromatogram.

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.

Entrainment function in the suprachiasmatic nucleus of streptozotocin-induced diabetic rats

The term for re-entrainment to a new light-dark cycle in streptozotocin (STZ)-induced diabetic rats was significantly longer than that in control rats. In STZ-induced diabetic rats, the same level of phase delay in the suprachiasmatic nucleus neuronal firing rhythm was observed in control rats after glutamate application. Therefore, 5-HT function in the hypothalamus is thought to be decreased in STZ-induced diabetic rats. These results suggest that postsynaptic neuronal function is still maintained in the suprachiasmatic nucleus of STZ-induced diabetic rats. Therefore, 5-HT mechanisms may play an important role in the maintenance of this function.

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.

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.

RGS domain in the amino-terminus of G protein-coupled receptor kinase 2 inhibits Gq-mediated signaling

We have previously shown that not only G protein-coupled receptor kinase (GRK) 2, but also a catalytically inactive Lys220Trp GRK2 decreases endothelin (ET)-1-induced inositol 1,4,5-trisphosphate (IP3) formation, and demonstrated the presence of phosphorylation-independent desensitization mechanism. To clarify the role of GRK2 other than that as a kinase, we characterized an RGS (regulator of G protein signaling)-like domain in the amino-terminus of GRK2. Both GRK2(1-181) and GRK2(54-174) suppressed Ca2+ responses induced by angiotensin II (Ang II) and ET-1, and bound directly with Galphaq but not Galphas nor Galphai3 in the presence of GDP and AlF4-. These results demonstrate that GRK2 regulates Gq-mediated signaling negatively by direct interaction between its RGS domain and the transitional state of Galphaq, as well as through phosphorylation of activated receptors by its kinase domain.

Comparison of MR imaging and urodynamic findings in benign prostatic hyperplasia

OBJECTIVE

In benign prostatic hyperplasia (BPH), it is uncertain whether the size of the prostate is related to the degree of urodynamically demonstrated bladder outlet obstruction. We compared MR imaging findings and urodynamic data in patients with surgically confirmed BPH.

MATERIALS AND METHODS

We prospectively studied 43 benign prostatic hyperplasia (BPH) patients in whom transurethral resection of the prostate (TURP) was planned. We obtained T1- and T2-weighted images in the transverse and sagittal planes with a 1.5 Tesla superconducting unit. The predicted volume of the inner gland and the peripheral zone were obtained on T2-weighted transverse images. Prostatic protrusion into the urinary bladder (IB protrusion) and the inner gland ratio (IG ratio: inner gland volume/total prostatic volume) were determined.

RESULTS

IB protrusion and inner IG ratio were significantly greater in patients with severe stenosis than in those without. A surgical capsule (SC) was seen in 20 of 25 patients (80%) with severe stenosis and 8 of 18 (44%) of those without it. The accuracy of IB protrusion + IG ratio, IB protrusion + surgical capsule, and IB protrusion + IG ratio + surgical capsule was 89%, and that of IG ratio + surgical capsule was 86%.

CONCLUSION

The inner gland ratio, protrusion into the bladder, and presence of surgical capsule were the most important factors in bladder outlet obstruction. The probability of outlet stenosis increases in patients with more than two of these criteria.

4-Dimethylaminobenzylamine as a sensitive chemiluminescence derivatization reagent for 5-hydroxyindoles and its application to their quantification in human platelet-poor plasma

A selective and sensitive high-performance liquid chromatographic method with chemiluminescence detection for the determination of 5-hydroxyindoles is described, based on the reaction of 5-hydroxyindoles with 4-dimethylaminobenzylamine. Serotonin, 5-hydroxyindole-3-acetic acid, 5-hydroxytryptophol, 5-hydroxyindole-3-acetamide and N-acetyl-5-hydroxytryptamine were used as model compounds to optimize the derivatization and chemiluminescent reaction. The reagent reacts with 5-hydroxyindoles in slightly alkaline media in the presence of potassium hexacyanoferrate(III) to give the corresponding derivatives, which can be separated on a reversed-phase column, Wakosil-II 5C18RS, with aqueous acetonitrile as an eluent. The derivatives were detected by peroxyoxalate chemiluminescence detection. The detection limits are in the range of 0.5-1.2 fmol per 100-microl injection. The method was applied to the simultaneous determination of serotonin and 5-hydroxyindole-3-acetic acid in human platelet-poor plasma.

Cell type-dependent transactivation or repression of mesoderm-restricted basic helix-loop-helix protein, POD-1/Capsulin

A family of basic-helix-loop-helix (bHLH) nuclear factors play important roles in controlling cell growth and differentiation as critical regulatory components in transcription. Here we describe molecular characterization of mesoderm-specific bHLH protein, POD-1/Capsulin. Transactivation property of POD-1/Capsulin was analyzed by the Gal4 fusion system in six mammalian cell lines. The results indicated that an activation property was shown in HT1080 and HeLa cells, but a repression activity in HepG2 cells. Mapping analysis for the transactivation and repression activities revealed that the C-terminal domain of POD-1/Capsulin is essential for the transactivation and both the N-terminal and C-terminal domains are contributed to the repression activities. Furthermore, in order to identify possible interactants of the POD-1/Capsulin, we performed yeast two-hybrid screen in a human kidney cDNA library, and identified a class A bHLH protein, ITF-2 as potential heterodimeric partner of the bHLH protein.

Antitumor agents 201. Cytotoxicity of harmine and beta-carboline analogs

Twenty-six beta-carbolines were evaluated for in vitro cytotoxicity in a human tumor cell line panel. Harmine (3) showed significant activity against several cell lines including three drug-resistant KB sublines with various resistance mechanisms. Alpha-(4-nitrobenzylidine) harmine (16) had a broad cytotoxicity spectrum (ED50 values from 0.3-1.2 microg/mL against 1A9, KB, SaOS-2, A549, SK-MEL-2, U-87-MG, and MCF-7 cells).

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.