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.

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.

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.

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.

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.

Determination of norepinephrine in microdialysis samples by microbore column liquid chromatography with fluorescence detection following derivatization with benzylamine

A microbore column liquid chromatographic method is described for the determination of norepinephrine (NE) in microdialysis samples from rat brain. The method is based on precolumn derivatization of NE with benzylamine in the presence of potassium hexacyanoferrate(III) resulting in a highly fluorescent and stable benzoxazole derivative. Typically, a 10-microl sample was mixed with 10 microl derivatization reagent containing 0.45 M Caps buffer (pH 12.0), 0.2 M benzylamine, 10 mM potassium hexacyanoferrate(III), and N,N-dimethylformamide (1:1:1:15, v/v). The derivatization was carried out at 50 degrees C for 20 min. Under these conditions only NE and epinephrine produced high fluorescence yields at excitation and emission wavelengths of 345 and 480 nm, respectively, while fluorescence of other catechols and 5-hydroxyindoles was quenched by 10-100 times. The NE derivative was separated on a reversed-phase column (100 x 1.0 mm i.d., packed with C18 silica, 5 microm) within 10 min with no late eluting peaks. The mobile phase consisted of 40 mM Britton-Robinson buffer (pH 7.5) containing 1 mM didodecyldimethylammonium bromide and acetonitrile (34%, v/v), the flow rate was 40 microl/min. The limit of detection (signal-to-noise ratio of 3) for NE was 90 amol in 10 microl sample injected. Microdialysis samples were collected in 5-min intervals from the probes implanted in the hippocampus, frontal cortex, or hypothalamus of awake rats. The basal extracellular NE levels in the respective areas were 4.7 +/- 0.9, 1.8 +/- 0.3, and 0.8 +/- 0.2 fmol/10 microl (mean +/- SE, n = 7). Perfusion with a Ringer solution containing 100 mM K+ increased hippocampal NE levels by 700%, while NE uptake inhibitors maprotiline and amitriptyline administered orally or subcutaneously increased extracellular NE in the frontal cortex by about 300%. On the other hand, reserpine (5 mg/kg) reduced cortical NE levels by 40% 3 h after the administration. This new fluorescence derivatization method provides better selectivity, sensitivity, and speed for NE determination than the electrochemical detection since no late-eluting compounds such as dopamine, serotonin, and their metabolites are detectable in the chromatograms of the microdialysis samples.

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.

Treatment of the nasal hump with preservation of the cartilaginous framework

Classically, nasal hump reduction is based on the partial resection of the cartilages and bones of the nose, as it was described by Joseph almost a century ago. The cartilaginous portion of the hump consists of a single unity formed by the two upper lateral cartilages and the septal cartilage. During hump reduction in the classic rhinoplasty, this structure is slashed in three pieces, which is the main cause of irregularities, shadows, and pinchings over the long-term results. Late follow-ups of the classical hump removal often show an inverted V-shaped shadow on the dorsum secondary to the destruction of the osseous-cartilaginous transition. The angle and relation between the septal and upper lateral cartilages are reduced, which may compromise the functional aspect. The destruction of the unique anatomy of the cartilaginous hump is one of the main causes of this functional and aesthetic sequela. Here, we present a technique that preserves the cartilaginous framework of the nasal hump by lowering it through the resection of a strip of septum, avoiding the problems described above.

[Angiotensin II and apoptosis]

Angiotensin II (AII), the effector octapeptide of the renin-angiotensin system, exerts a multitude of actions, including vascular contraction, aldosterone secretion, catecholamine release, glycogenolysis, and decreased renal filtration. These diverse actions are mediated through AII receptor subtypes present in a variety of target tissues. Molecular cloning studies have identified two major types of mammalian AII receptors, designated AT1 and AT2, which are classified as a typical family of seven transmembrane guanyl nucleotide-binding protein (G-protein) coupled receptors from hydropathy analyses. Mainly, if not all, of the actions of AII are mediated by AT1 that has been well characterized. Recently, AT2 is found to exert growth inhibitory and proapoptotic effects, but its physiological role is still unclear. The molecular mechanism and the physiological importance of signaling pathways via these receptors remain to be elucidated.

Expression and characterization of mouse angiotensin II type 1a receptor tagging hemagglutinin epitope in cultured cells

The octapeptide angiotensin II mediates the physiological actions of the renin-angiotensin system through activation of several angiotensin II receptor (AT) subtypes, in particular AT1 (AT1a and AT1b in the case of rodents). Although we and others have generated mutant mice in which the AT1a gene was disrupted, the function of mouse AT1 remains to be fully elucidated, due to the lack of effective tools involving antibodies against AT1 for detecting biological responses in cellular conditions. To avoid these problems, we constructed the hemagglutinin (HA)-tagged mouse AT1a, and stably introduced this recombinant receptor into human embryonic kidney 293-T cells. Radioligand binding of [(125)I] angiotensin II to AT1a was specific, saturable, and reversible. Scatchard analysis demonstrated that the transfected receptor had a dissociation constant of 1.7 nM with a density of 1.2 x 10(5) sites/cells. Angiotensin II stimulated a rapid increase in cytosolic free calcium, and angiotensin II-induced phosphorylation of extracellular signal-regulated kinases (Erk) was found in a dose-dependent manner. After solubilization, Western blot analysis showed specific interactions between an anti-HA antibody and HA-tagged mouse AT1a. Furthermore, a significant proportion of HA-tagged mouse AT1a was specifically immunoprecipitated with this antibody. In the immunocytochemical and electronmicroscopic studies, treatment of this cell line with angiotensin II resulted in decrease in signals of the surface receptors. Based on these results, the cell line established here provides an excellent tool for studying angiotensin II actions mediated through mouse AT1a, at sub-nanomolar concentrations.

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.

Primary tumours of the greater omentum

Primary tumours of the greater omentum are very rare. Ultrasound allows the detection and characterization of such lesions, but determination of their precise anatomical location is usually difficult by US. Computed tomography determines the omental origin of the tumour. Thus, when US reveals an abdominal tumour of unknown origin, the possibility of an omental tumour, although rare, must be kept in mind and CT should be performed.