Characterization of sonographically indeterminate ovarian tumors with MR imaging. A logistic regression analysis

PURPOSE

The goal of this study was to maximize the discrimination between benign and malignant masses in patients with sonographically indeterminate ovarian lesions by means of unenhanced and contrast-enhanced MR imaging, and to develop a computer-assisted diagnosis system.

MATERIAL AND METHODS

Findings in precontrast and Gd-DTPA contrast-enhanced MR images of 104 patients with 115 sonographically indeterminate ovarian masses were analyzed, and the results were correlated with histopathological findings. Of 115 lesions, 65 were benign (23 cystadenomas, 13 complex cysts, 11 teratomas, 6 fibrothecomas, 12 others) and 50 were malignant (32 ovarian carcinomas, 7 metastatic tumors of the ovary, 4 carcinomas of the fallopian tubes, 7 others). A logistic regression analysis was performed to discriminate between benign and malignant lesions, and a model of a computer-assisted diagnosis was developed. This model was prospectively tested in 75 cases of ovarian tumors found at other institutions.

RESULTS

From the univariate analysis, the following parameters were selected as significant for predicting malignancy (p< or =0.05): a solid or cystic mass with a large solid component or wall thickness greater than 3 mm; complex internal architecture; ascites; and bilaterality. Based on these parameters, a model of a computer-assisted diagnosis system was developed with the logistic regression analysis. To distinguish benign from malignant lesions, the maximum cut-off point was obtained between 0.47 and 0.51. In a prospective application of this model, 87% of the lesions were accurately identified as benign or malignant.

CONCLUSION

Benign and malignant ovarian lesions can be distinguished in most sonographically indeterminate lesions by means of parameters obtained from contrast-enhanced MR imaging.

Micellar electrokinetic capillary chromatography of benzodiazepine antiepileptics and their desmethyl metabolites in blood

A fast and reliable method for the MEKC separation and determination of benzodiazepine antipileptics and their active metabolites in serum has been developed, using a separation buffer composed of borate (pH 9.5), SDS (18 mM), and acetonitrile (14%) as an organic modifier. The method is sensitive enough to be used clinically with a precision of less than 3% for the analysis of nitrazepam, clonazepam, clobazam, diazepam and their desmethyl metabolites in serum.

Nitric oxide and aneurysm formation in Kawasaki disease

The objective of this study is to show that nitric oxide plays a role in the development of coronary artery abnormalities in Kawasaki disease. We examined nitrite+nitrate, biopterin and neopterin in 316 urine samples of 34 patients with Kawasaki disease, those of 24 patients with other diseases, and those of 25 healthy children acting as a control group, because urinary nitrite + nitrate are reportedly useful as markers of nitric oxide generation in vivo, and pathways for neopterin-biopterin synthesis and nitric oxide generation are tightly coupled. In our study, the children with Kawasaki disease excreted more urinary nitrite + nitrate and neopterin than did the healthy control group children and excreted abnormally high quantities more often than did the patients with other diseases. Good relationships were found between the urinary nitrite + nitrate levels and the urinary biopterin levels, and between these biopterin levels and the urinary neopterin levels. Nitric oxide is therefore thought to be generated in abnormally high quantities, and to be closely related to the pathology of Kawasaki disease and to the development of coronary artery abnormalities. The role of nitric oxide in Kawasaki disease should be further studied to elucidate the pathophysiology of the disease and to aid in the development of new treatments.

Early molecular specification in the hippocampal rudiment: isolation of genes expressed in a region-specific manner in the embryonic telencephalon

During development, the structure of the telencephalon is dramatically transformed by region-specific proliferation and differentiation of neuroepithelial cells. To understand mechanisms of morphogenesis in the telencephalon, a search was made for genes expressed in a region-specific manner in the dorsal telencephalon of embryonic rats. Dorso-lateral and dorso-medial portions of the telencephalon were taken from rat fetuses on embryonic day (E) 13. Genes expressed in each portion were compared by a modified differential display method. Among more than 4000 cDNA fragments, four fragments termed M1, M1', M2 and M3 were found only after amplification of cDNAs derived from the dorso-medial portion of the telencephalon. Nucleotide sequence and Northern blot analyses showed that M1 and M1' were identical and that M2 and M3 were related genes. In situ hybridization revealed that M1 was expressed in a restricted portion of the hippocampal rudiment with a sharp boundary. M2 and M3 were expressed in the hippocampal rudiment with a more diffuse boundary than that of M1. Expression of M2 and M3 was also found in the most anterior part of the medial diencephalon with a caudal extension along the dorsal midline. These results suggest that at least two types of molecular specification occur in the dorso-medial telencephalon, contributing to the construction of the hippocampal elements during early stages of development.

Struma ovarii: MR appearances

BACKGROUND

Analysis of unenhanced and contrast-enhanced magnetic resonance (MR) images of struma ovarii, a rare benign neoplasm of the ovary, is the aim of this study.

METHODS

T2-weighted and Gd-DTPA-enhanced T1-weighted MR images of five histologically proven struma ovarii were evaluated retrospectively.

RESULTS

In all patients, unenhanced and contrast-enhanced T1-weighted MR images showed complex cystic masses composed of multiple cysts and a solid component, indicating the presence of large and small thyroid follicles. In four patients, the cyst fluid was hypointense on T1-weighted images and hyperintense on T2-weighted images. In one patient, the fluid was hyperintense on T1-weighted images and hypointense on T2-weighted images due to hemorrhage.

CONCLUSION

A complex mass composed of multiple cysts and a solid component, indicating the presence of large and small thyroid follicles, appeared to be a characteristic MR finding of struma ovarii.

Short communication: the value of embolization therapy in painful osseous metastases from hepatocellular carcinomas; comparative study with radiation therapy

We evaluated the therapeutic effect of transcatheter arterial embolization therapy (TAE) for painful osseous metastases from hepatocellular carcinoma (HCC) in comparison with radiation therapy (RT). TAE using gelatin sponge particles was performed for seven lesions in seven patients. Selective catheterization and embolization were successfully performed in all lesions. Within 10 days after TAE, complete pain relief (CR), partial relief (PR) and no relief (NR) were attained in 57%, 29% and 14%, respectively. RT was used to treat 34 lesions in 22 patients. The dose fractionation schedules were in the range 28.0-50.4 Gy, with 1.8-4.0 Gy per fraction. CR, PR and NR were attained in 47%, 47% and 6%, respectively. There were no serious complications related to these treatments. Both TAE and RT are effective and the treatment of choice should be selected on an individual basis.

A role of peroxides in Ca2+ ionophore-induced apoptosis in cultured rat cortical neurons

The implication of reactive oxygen species for the Ca2+ ionophore ionomycin-induced apoptosis was investigated in cultured cortical neurons from embryonic rats. Ionomycin increased the production of intracellular peroxides as measured by flow cytometric analysis with 6-carboxy-2'7'-dichorodihydrofluorescein diacetate, di(acetoxymethyl ester). Low doses of ionomycin increased the level of manganese-superoxide dismutase (Mn-SOD). In addition, N-acetyl-L-cysteine prevented apoptotic neuronal death induced by ionomycin in a dose-dependent manner. Buthionine sulfoximine suppressed the effect of N-acetyl-L-cysteine. These results suggest that peroxides and redox-regulation play an important role in the apoptosis of neurons induced by elevation of intracellular Ca2+ concentration.

Enhanced expression of the protein kinase substrate annexin in human hepatocellular carcinoma

Annexin (AX) constitutes a new family of Ca2+-dependent membrane-binding proteins; 13 of them have been described. Among these, annexin-1 (AX-I) has displayed many biological functions in vitro. Its actual role in vivo, however, remains unknown. We already reported that AX-I was expressed in proliferating (regenerating) hepatocytes at both protein and messenger RNA (mRNA) levels. The role of AX-I in human hepatocellular carcinoma (HCC) remains obscure. In this study, the amounts of AX-I at protein and mRNA levels, as well as its localization, have been determined in the normal human liver, chronic hepatitis liver, and nontumorous and tumorous portions of HCC. AX-I was rarely found in normal and chronic liver tissues, whereas it is overexpressed at both the transcriptional and translational levels in tumorous and nontumorous regions of HCC. In addition, more AX-I was expressed in the tumorous portion than the nontumorous portion of HCC. AX-I was present in the hepatocytes and HCC cells, localized mainly in the cytoplasm. AX-I was expressed in poorly differentiated cancer cells. Furthermore, AX-I was tyrosine-phosphorylated in HCC. We also found that some of the AX-I- positive hepatocytes in the nontumorous tissues were derived from a particular subset of parenchymal cells (stem or oval cells). These results indicate that AX-I plays an important role in the malignant transformation process leading to HCC and that it is closely related to the histological grade of HCC. HCC would offer a novel tool with which to study the function of AX-I in malignant transformation.

[MR appearance of fat distribution in ovarian teratoma: pathologic correlation]

Magnetic resonance (MR) imaging was performed in 45 patients with 52 surgically proved ovarian teratomas. MR findings of these tumors were classified into three types depending on the degree of fatty proportions in the tumor. The majority of teratomas were filled with fatty tissue in the cystic cavity (n = 43, 82.7%). In 5 tumors (9.6%), fatty tissue was seen at the edge or within the cyst wall. Fatty tissue could not be seen in any part of the tumor in 4 cases (7.7%). The tumors without a fatty component on MR images tend to have fewer sebaceous glands and less fatty tissue within the cyst wall than tumors with an abundant fatty component. Demonstration of fatty tissue is pathognomonic for these tumors. However, tumors with a small amount of fatty tissue may be indistinguishable from cystic ovarian tumors on MR images.

Synthesis and characterization of a carbene-generating biotinylated lactosylceramide analog as a novel chromogenic photoprobe for GM3 synthase

A new biotinylated lactose derivative bearing a nitro-substituted chromogenic diazirine was synthesized. The biotinyl group within the structure enabled the performance of a convenient assay of GM3 synthase based on avidin-biotin technology, and the Km values of this biotinylated photoprobe were determined as 40 and 47 microM using bovine brain and rat liver Golgi as enzyme sources, respectively. Furthermore, the sialylation of lactosylceramide, a natural acceptor substrate for GM3 synthase, was competitively inhibited by this synthetic analog. The reagent could be a useful chromogenic photoprobe for GM3 synthase.

Detection of hepatocellular carcinoma by intraarterially enhanced ultrasonography with CO2 microbubbles. Comparison with DSA, dynamic CT, and Lipiodol CT

PURPOSE

To evaluate the diagnostic value of contrast-enhanced US with CO2 microbubbles (EU) for HCCs. Detectability was compared with DSA, dynamic CT, and Lipiodol CT.

MATERIAL AND METHODS

Forty-seven histologically proven HCCs detected with US were evaluated with EU, DSA, and dynamic CT. In 23 patients (35 lesions), Lipiodol CT was also performed. The size of the tumors ranged from 8 to 71 mm (average 28.1 mm); 24 lesions were smaller than 20 mm and 23 lesions were larger than 20 mm.

RESULTS

Overall detection was possible in 40 of 47 lesions (85%) by EU, in 32 of 47 (68%) by DSA, in 33 of 47 (74%) by dynamic CT, and in 27 of 35 (77%) by Lipiodol CT. In tumors smaller than 20 mm, detection was possible in 21 of 24 lesions (88%) by EU, 14 of 24 (58%) by DSA, 14 of 24 (58%) by dynamic CT, and 11 of 17 (65%) by Lipiodol CT.

CONCLUSION

EU has significant diagnostic value for detection of HCCs, particularly tumors smaller than 20 mm.

Studies on metabolites of mycoparasitic fungi. V. Ion-spray ionization mass spectrometric analysis of trichokonin-II, a peptaibol mixture obtained from the culture broth of Trichoderma koningii

The sequence of a peptide, trichokonin-II (TK-II), obtained from the culture broth of Trichoderma koningii OUDEMANS, was examined by ion-spray ionization mass spectrometry (ISI-MS), including the collision-induced dissociation (CID) technique. TK-II was concluded to be a mixture of three peptaibols, TK-IIa, TK-IIb, and TK-IIc.

Role of a rat membrane inhibitor of complement in anti-basement membrane antibody-induced renal injury

In the kidneys of anti-glomerular basement membrane (anti-GBM) antibody disease, binding of antibodies to tubular basement membrane (TBM) is often observed. The present work was performed to explore the mechanisms of binding of anti-GBM antibodies to TBM in vivo with special reference to 5I2Ag, a rat membrane inhibitor of complement which regulates complement activation at C3 convertase level. To suppress functions of renal 5I2Ag, F(ab')2 fragment of 5I2 (a neutralizing mAb against 5I2Ag) was perfused in the left kidney and then blood circulation was restored. Mild proteinuria ( < 10 mg/16 hr) was observed during first several days. Five days later, there were tubulointerstitial injuries defined by tubular vimentin staining and leukocyte infiltration. Significant deposition of C3 was observed in the capillaries and in TBM. In rats intravenously injected with rabbit anti-rat GBM antibodies five minutes after kidney perfusion with 5I2, strong binding of rabbit IgG to TBM was observed at one and five days after injection. Although these rats showed mild proteinuria comparable to those perfused with 5I2 and those injected with normal rabbit serum, tubulointerstitial injury was significantly enhanced at Day 5. In contrast, rats perfused with irrelevant mAb and injected with anti-GBM antibodies did not show any significant binding of antibodies to TBM nor tubulointerstitial injury. Furthermore, rats which were made proteinuric by puromycin aminonucleoside and injected with anti-GBM antibodies did not show any significant binding of rabbit IgG to TBM. These results indicate that 5I2Ag, a rat membrane inhibitor of complement at the C3 convertase level, regulates vascular permeability in the living kidney, and that dysfunction or decreased expression of this molecule leads to increased accessibility of anti-GBM antibodies to TBM.

External radiation therapy of prostatic carcinoma and its relationship to hormonal therapy

From 1980 to 1990, a total of 54 patients with prostatic carcinoma were treated with external radiation therapy at the Kumamoto National Hospital. Ten patients were classified as Stage B, 22 as Stage C, and another 22 as Stage D according to the American Urological Association Clinical Staging System. The 5-year survival for all 54 patients was 30%. The 5-year disease-specific survival was 67% for Stage B, 47% for Stage C, and 26% for Stage D. The 5-year survival was 43% for patients in whom radiation therapy was initiated immediately after the first diagnosis or with less than one year of hormonal therapy, while it was 0% for patients in whom radiation therapy was initiated after more than one year of hormonal therapy (p = 0.01). The cause of intercurrent death was acute myocardial infarction in four patients and acute cardiac failure in one. Four of these patients received hormonal therapy for more than one year. The incidence of radiation-induced proctitis was not severe. This study suggests that long-term hormonal therapy prior to radiation therapy worsens the prognosis of patients with prostatic carcinoma.

Studies on metabolites of mycoparasitic fungi. IV. Minor peptaibols of Trichoderma koningii

Three minor peptaibols, trichokonins (TKs)-Ia, Ib, and IX, were obtained from the culture broth of Trichoderma koningii Oudemans. Primary structures of these peptaibols were elucidated by ion-spray ionization mass spectrometry (ISI-MS) including the collision-induced dissociation (CID) technique together with two-dimensional nuclear Overhauser enhancement spectroscopy (NOESY).

Involvement of N-linked carbohydrate chains of pig zona pellucida in sperm-egg binding

The sperm receptor activity of pig zona pellucida has been previously shown to exist in one of the components, pig zona protein 3 alpha (PZP3 alpha), that can be purified after the removal of sialylated and/or sulfated N-acetylpoly(lactosamine) by digestion with endo-beta-galactosidase. In this study, we examined whether N-linked or O-linked carbohydrate chains are involved in the sperm receptor activity of pig zona pellucida. The elimination of N-linked carbohydrate chains from endo-beta-galactosidase-digested PZP3 alpha by digestion with N-glycanase markedly reduced its inhibitory effect on sperm-egg binding in an in vitro competition assay, whereas the elimination of O-linked carbohydrate chains by alkali treatment hardly reduced the inhibitory effect. These results indicate that N-linked carbohydrate chains of PZP3 alpha play a major role in mediating the sperm binding of zona pellucida in pig.

Dynamic MRI of small renal cell carcinoma

OBJECTIVE

To evaluate the appearance of contrast-enhanced dynamic MRI of small renal cell carcinoma (RCC) (< 3 cm diameter).

MATERIALS AND METHODS

Twenty-seven patients with 28 small RCCs were studied by both conventional spin echo and contrast-enhanced dynamic MRI for tumor detection and characterization. All tumors were detected by contrast-enhanced CT and confirmed by operation. Dynamic MRI was performed using a breath-hold fast low angle shot technique after rapid injection of gadolinium diethylenetriamine pentaacetic acid (Gd-DTPA). Characterization of a renal mass was done by the visual analysis of tumor vascularity as well as quantitative assessment of the contrast noise ratio (CNR) and degree of enhancement.

RESULTS

With conventional spin echo MR and dynamic MR, 18 and 26 of 28 small RCCs were detected, respectively. In the dynamic study the tumor/renal medulla contrast was marked at 90-120 s after administration of Gd-DTPA (CNR:15.1). The tumor/renal medulla contrast in the dynamic study was more marked than that of postcontrast T1-weighted imaging (CNR, -0.25); T2-weighted imaging (CNR, 3.1); and T1-weighted imaging (CNR, -0.76).

CONCLUSION

Contrast-enhanced dynamic MRI is a useful technique for the diagnosis of small RCC especially in a patient with renal insufficiency or allergy to iodinated contrast material.

US-guided liver biopsy: predicting the effect of interventional treatment of hepatocellular carcinoma

PURPOSE

To analyze the results of ultrasound (US)-guided biopsy as a predictor of the outcome of interventional treatment of hepatocellular carcinoma (HCC).

MATERIALS AND METHODS

US-guided biopsy was performed in 125 lesions in 102 high-risk patients, before transcatheter arterial embolization (TAE) (82 lesions) or before percutaneous ethanol injection (PEI) therapy (25 lesions, including 14 lesions previously treated with TAE). Pathologic results were correlated with treatment effects.

RESULTS

Results of biopsy confirmed 107 HCCs, which were classified as early (n = 17), frank (n = 67), sclerosing (n = 12), or poorly differentiated or undifferentiated (n = 11). Hypervascularity was observed in most frank HCCs, with a good response to TAE. Tumor vascularity in early or sclerosing HCCs was slight and did not respond to TAE. Sclerosing and poorly differentiated or undifferentiated HCCs enlarged after treatment, whereas early HCCs did not. Early HCCs were treated successfully with PEI therapy; sclerosing HCCs responded poorly to PEI therapy.

CONCLUSION

Evaluation of histologic subtype of HCC by means of US-guided biopsy is essential, because subtype may affect treatment planning.

Magnetic resonance characteristics of intrapelvic haematomas

Although haematomas in the female pelvis are not rare, their magnetic resonance (MR) appearance has not been well characterized. Accordingly, we analysed the MR appearances of various stages of haematomas in the female pelvis. A retrospective analysis of 35 haematomas in 28 patients sequentially imaged with a 1.5 T MR unit was performed. The time interval between the insult and MR imaging was determined and the appearances of the haematoma were evaluated. The results were compared with those in the central nervous system. The evolution of haematomas in the pelvis appeared similar to that of haematomas in the brain, and four stages (acute, early subacute, late subacute and chronic) were identified according to the signal intensity pattern on T1 and T2 weighted images. Pelvic haematomas differed from intracranial haematomas in the following features: (1) The speed of evolving pelvic haematomas was gradual. (2) In the centre of acute haematomas, slightly hyperintense areas were seen on both sequences, suggesting residual oxyhaemoglobin. (3) Haematomas evaluated in the early subacute stage had complex appearances. (4) In older haematomas, central intermediate signal intensity areas, presumably due to diamagnetic hemichromes, became predominant on T1 weighted images. In conclusion, although the evolution of a pelvic haematoma is similar to that of a brain haematoma, its speed is gradual and MR appearances are somewhat different due to environmental differences.

Identification of the electrophilic substrate-binding site of glutathione S-transferase P by photoaffinity labeling

We determined the electrophilic substrate-binding site of rat glutathione S-transferase P (GST-P) by photoaffinity labeling using the photosensitive compound S-[2-(2-fluoro-4-nitrophenoxy)ethyl]glutathione. This photosensitive glutathione analogue inhibited the catalytic activity in a competitive manner against both glutathione and 1-chloro-2,4-dinitrobenzene, a putative electrophilic substrate. The enzyme kinetics indicated that the photoactivatable glutathione analogue was specifically bound at the active site, which consisted of glutathione-binding (G-site) and the electrophilic substrate-binding (H-site) regions. The procedure involved the following steps: S-[2-(2-fluoro-4-nitrophenoxy)ethyl]glutathione was photochemically reacted with a purified recombinant GST-P expressed in Escherichia coli using ultraviolet irradiation for 30 min on ice. After the reaction, only the GST-P complexed with the glutathione analogue was prepared with glutathione-immobilized agarose. The GST-P covalently bound with the analogue was digested with lysyl endopeptidase (Achromobacter protease I), and the peptides were separated by high-performance liquid chromatography. Only a single major peak with appreciable absorbance at 340 nm was observed by peptide mapping. The peptide was collected and analyzed using an automated peptide sequencer (ABI 477A). Amino acid sequence analysis showed that this peptide consisted of seven amino acid residues corresponding to the sequence at positions 122-128 of GST-P (Ala-Leu-Pro-Gly-Xaa-Leu-Lys). No appreciable phenylthiohydantoin-amino acid was detected at the fifth cycle, which indicated that His126 was chemically labeled with the photosensitive glutathione analogue. It was concluded that His126 was one of the amino acid residues forming the electrophilic substrate-binding site of GST-P.

MR imaging of atypical polypoid adenomyoma

The magnetic resonance (MR) appearances of three cases of atypical polypoid adenomyoma are reported. The signal intensity of the tumor was similar to that of adenomyosis on T2-weighted MR Imaging (MRI). On contrast-enhanced study, irregular enhancement was seen in hyperintense areas on T2-weighted images. Atypical polypoid adenomyoma can be characterized as a hypointense polypoid mass with hyperintense foci on T2-weighted MR images, resembling the appearance of adenomyosis.

Unresectable hepatocellular carcinoma: analysis of prognostic factors in transcatheter management

PURPOSE

To evaluate the effect of transcatheter management of hepatocellular carcinoma (HCC) on survival.

MATERIALS AND METHODS

A prospective trial of transcatheter arterial embolization (TAE) was performed in patients with unresectable HCC. Three hundred twenty-two patients (265 men, 57 women; age range, 30-83 years) underwent TAE alone: 60 patients underwent TAE with gelatin sponge (GS) that contained anticancer agents (protocol 1); 78, TAE with GS and iodized oil mixed with anticancer agents (protocol 2); and 159, TAE with iodized oil with anticancer agents (protocol 3). A Cox proportional hazard model was used to analyze prognostic factors.

RESULTS

In the randomized group (n = 272), survival rates for protocols 1, 2, and 3 were 80.4%, 86.3%, and 65.9%, respectively, at 1 year. Findings of analysis of prognostic factors showed that extrahepatic metastases, ascites, tumor extension, and icterus were the important factors.

CONCLUSION

TAE with GS was superior to TAE without GS. Patient characteristics were important factors for survival.

Synthesis of nitrodiazirinyl derivatives of neurotoxin II from Naja naja oxiana and their interaction with the Torpedo californica nicotinic acetylcholine receptor

Five singly modified nitrodiazirine derivatives of neurotoxin II (NT-II) from Naja naja oxiana were obtained after NT-II reaction with N-hydroxysuccinimide ester of (2-nitro-4-[3-(trifluoromethyl)-3H-diazirin-3yl]phenoxy)acet ic acid followed by chromatographic separation of the products. To localize the label positions, each derivative was first UV-irradiated and then subjected to reduction, carboxymethylation, and trypsinolysis. Tryptic digests were separated by reversed phase-HPLC, the labeled peptides being identified by mass spectrometry. The derivatives containing the photolabel at the position Lys 25, Lys 26, Lys 44, or Lys 46 were [125I]iodinated by the chloramine T procedure. Each iodinated derivative was found to form photoinduced cross-links with the membrane-bound nicotinic acetylcholine receptor (AChR) from Torpedo californica. The pattern of labeling the receptor's alpha, beta, gamma, or delta subunits was dependent on the photolabel position in the NT-II molecule and differed from that obtained earlier with an analogous series of p-azidobenzoyl derivatives of NT-II. The results obtained indicate that (i) different sides of the neurotoxin molecule are involved in the AChR binding, and (ii) fragments of the different AChR subunits are located close together at the neurotoxin-binding sites.