Restriction fragment length dimorphism-PCR method for the detection of extended-spectrum beta-lactamases unrelated to TEM- and SHV-types

The diagnostic ability of the restriction fragment length dimorphism-polymerase chain reaction (RFLD-PCR) method was evaluated. Seven primer pairs, newly designed from 44 beta-lactamase genes encoding extended-spectrum beta-lactamases not related to TEM- and SHV-types, were used to differentiate OXA-2, FOX-3, CMY-3, IMP-1, and IMI-1 beta-lactamases. The RFLD-PCR was carried out successfully, and these genes were differentiated by the sizes of their PCR products and by the difference in restriction fragment length when each amplicon was digested with a unique restriction enzyme. This discriminatory detection of the genes was confirmed by sequencing the PCR products.

Lignans from the rhizomes of Coptis japonica differentially act as anti-inflammatory principles

Coptis japonica Makino (Ranunculaceae) is known to possess several biological activities such as anti-inflammatory effects. In this study, five lignans, isolariciresinol (1), lariciresinol glycoside (2), pinoresinol (3), pinoresinol glycoside (4) and syringaresinol glycoside (5), isolated from the rhizomes of C. japonica were tested to evaluate their in vitro anti-inflammatory effects. Pinoresinol and isolariciresinol showed higher inhibitory effects on TNF-alpha production, whereas syringaresinol glycoside strongly suppressed lymphocyte proliferation. The results indicate that the lignans may differentially modulate inflammatory cell responses, suggesting that these compounds may participate in anti-inflammatory processes by C. japonica.

Color and power Doppler twinkling artifacts from urinary stones: clinical observations and phantom studies

OBJECTIVE

The purpose of this study was to determine whether color and power Doppler twinkling artifacts could be considered an additional diagnostic sonographic feature of urinary stones.

SUBJECTS AND METHODS

A prospective study was performed in 32 patients with 20 renal stones and 16 ureteral stones to assess how often urinary stones show twinkling artifacts on Doppler sonography. Gray-scale images and color, power, and spectral Doppler images were obtained in all patients. All sonographic examinations were performed with a 3.5- or 5-MHz curvilinear phased array probe. The images were then analyzed for the presence, appearance, and intensity of the artifacts. Phantom experiments were performed with various kinds of urinary stones with high-megahertz linear phased array probes. The effects on the artifacts of the composition of the stones, of the Doppler velocity scale, and of the focal zone were investigated.

RESULTS

Thirty (83%) of 36 urinary stones showed color and power Doppler twinkling artifacts, which appeared as a rapidly changing color complex seen persistently behind stones like a comet's tail. Twenty-two of 30 stones with the twinkling artifacts showed strong intensity artifacts. Spectra with saturated amplitude were obtained from all 30 stones showing color Doppler artifacts. In phantom experiments, the artifacts originated from all stones. The velocity range did not affect the artifacts, whereas focal zone did.

CONCLUSION

Color Doppler twinkling artifacts from urinary stones occur frequently and may be considered an additional sonographic feature of urinary stones. The observation of these artifacts may be helpful in determining the presence of urinary stones.

Systemic administration of immunostimulatory DNA sequences mediates reversible inhibition of Th2 responses in a mouse model of asthma

This study investigated whether immunostimulatory DNA sequences (ISS) induce a transient or sustained inhibition of Th2 responses to inhaled antigen. We sensitized mice with subcutaneous injections to develop a Th2 response to ovalbumin (ova) and then administered a dose of ISS prior to ova inhalation challenge. Mice were then rechallenged with ova by inhalation a second time at varying time points after the first ova inhalation (1 to 8 weeks later) to determine whether the ISS dose administered prior to the first ova inhalation protected against a subsequent second ova inhalation challenge. A single dose of ISS inhibited the Th2 response to the first inhalation of ova antigen, as well as 4 weeks later to the second inhalation of ova. However, ISS did not inhibit a Th2 response to the second inhalation of ova 8 weeks later. The reversible inhibition of Th2 responses at 8 weeks suggests the need for repeated ISS administration at monthly intervals.

Effect of omeprazole on the pharmacokinetics of moclobemide according to the genetic polymorphism of CYP2C19

BACKGROUND

Moclobemide, an antidepressant with selective monoamine oxidase-A inhibitory action, is known to be metabolized by CYP2C19 and is also reported to be an inhibitor of CYP2C19, CYP2D6, and CYP1A2. To confirm the involvement of CYP2C19, we performed a pharmacokinetic interaction study.

METHODS

The effect of omeprazole on the pharmacokinetics of moclobemide was studied in 16 healthy volunteers. The volunteer group comprised 8 extensive metabolizers and 8 poor metabolizers of CYP2C19, which was confirmed by genotyping. Subjects were randomly allocated into two sequence groups, and a single-blind, placebo-controlled, two-period crossover study was performed. In study I, a placebo was orally administered for 7 days. On the eighth morning, 300 mg of moclobemide and 40 mg of placebo were coadministered with 200 mL of water, and a pharmacokinetic study was performed. During study II, 40 mg of omeprazole was given each morning instead of placebo, and pharmacokinetic studies were performed on the first and eighth day with 300 mg of moclobemide coadministration.

RESULTS

The inhibition of moclobemide metabolism was significant in extensive metabolizers even after a single dose of omeprazole. After daily administration of omeprazole for 1 week, the pharmacokinetic parameters of moclobemide and its metabolites in extensive metabolizers changed to values similar to those in poor metabolizers. In poor metabolizers, no remarkable changes in the pharmacokinetic parameters were observed.

CONCLUSION

Our results show that CYP2C19 is an important enzyme in the elimination of moclobemide and that it is extensively inhibited by omeprazole in extensive metabolizers, but not in poor metabolizers.

In vitro inhibitory effect of protopanaxadiol ginsenosides on tumor necrosis factor (TNF)-alpha production and its modulation by known TNF-alpha antagonists

Ginsenosides are the major principles of Panax ginseng C. A. Meyer (Araliaceae) used as a mild oriental folk medicine. In this report, we have examined the inhibitory potency of protopanaxadiol ginsenosides (PPDGs) such as Rb1, Rb2 and Rc, and their co-treatment effect with known tumor necrosis factor (TNF)-alpha antagonists on TNF-alpha production in either murine (RAW264.7) or human (U937) macrophages stimulated with lipopolysaccharide (LPS). Rb1, and Rb2 strongly suppressed TNF-alpha production in RAW264.7 cells with an IC50 of 56.5 and 27.5 microM, respectively, and in differentiated U937 cells with an IC50 of 51.3, and 26.8 microM, respectively. The inhibitory activity of Rb1 and Rb2 was significantly increased by pharmacological agents against protein kinase C, protein tyrosine kinase, and protein kinase A, and anti-rheumatoid arthritis drugs, such as chloroquine and steroid drugs. In contrast, only cyclic AMP phosphodiesterase (cAMP PDE) inhibitors among cAMP-elevating agents did not change the inhibitory potency of PPDGs. These data suggest that PPDGs may possess potential therapeutic efficacy against TNF-alpha mediated disease and the therapeutic potency of PPDGs may be enhanced when co-treated with various kinds of known TNF-alpha antagonists but not with cAMP PDE inhibitors.

Savinin, a lignan from Pterocarpus santalinus inhibits tumor necrosis factor-alpha production and T cell proliferation

Two lignans were isolated from the heartwood of Pterocarpus santalinus by activity-guided fractionation and investigated for their biological properties and molecular mechanism of action. On the basis of their spectroscopic data, these compounds were identified as savinin (1) and calocedrin (2), dibenzyl butyrolactone-type lignan compounds having an alpha-arylidene gamma-lactone structure. These lignans significantly inhibited tumor necrosis factor (TNF)-a production in lipopolysaccharide (LPS)-stimulated RAW264.7 cells, and T cell proliferation elicited by concanavalin (Con A), without displaying cytotoxicity. The molecular inhibitory mechanism of compound 1 was confirmed to be mediated by the non-polar butyrolactone ring, according to a structure-relationship study with structurally related and unrelated compounds, such as arctigenin (a dibenzyl butyrolactone type lignan), eudesmin (a furofuran type lignan), isolariciresinol (a dibenzylbutane type lignan), and cynaropicrin (a sesquiterpene lactone). The results suggest that savinin may act as an active principle in the reported biological activities of P. santalinus, such as antiinflammatory effect, by mediation of the butyrolactone ring as a valuable pharmacophore.

Determining the cascade of passive scalar variance in the lower stratosphere

Using aircraft data from 7630 commercial flights, we determine the flux of temperature and ozone variance from large to small scales in the lower stratosphere. The relation that we use for this purpose is a form of the classical Yaglom relation [A. M. Yaglom, Dokl. Akad. Nauk SSSR 69, 743 (1949)] for the third-order scalar-velocity structure function. We find that this function is negative and that it depends linearly on separation distance in the mesoscale range for temperature as well as ozone.

Mammary gland tumor in transgenic mice expressing targeted beta-casein/HPV16E6 fusion gene

The human papillomaviruses (HPV)-16 and HPV-18 referred to as high-risk HPVs are strongly associated with anogenital malignancies as well as benign epithelial cysts. It has been demonstrated that transgenic mice carrying HPV-16 E6-E7 under the control of the MMTV LTR developed malignant tumors including salivary gland carcinoma, lymphoma, skin histiocytomas and testicular tumors in a non-mammary gland specific manner. Another regulatory unit of rat beta-casein gene can confer the expression of fusion gene preferentially in the mammary glands of transgenic mice in a developmentally regulated manner. In order to generate mammary tumor formation in transgenic mice directing HPV16E6 gene alone into the mammary gland, this regulatory unit was fused to the E6 gene of HPV-16 type to constructing fusion gene. By screening 51 newborn founder transgenic mice, three mice carrying transgenes were identified. One line termed TG32 developed in a mammary gland tumor with large subcutaneous mass in the left rib region at 17 months of age. The levels of E6 transcript in the mass-tumor of TG32 line were lower than those in non-tumor mammary gland of identical TG32 and of TG250. In each tissue of TG32 line, high expression of E6 transcript was detected both in the mammary gland and brain. Histological analysis showed that cells from mammary gland tumor of the TG32 line had also hyperplasia appearance, with irregular or increased total number of mitotic rate. These observations suggest that developing phenotype and the level of E6 transcripts in the process of malignant transformation may have different mechanisms involving the capacity to bind and destabilize p53, although for confirmation it is necessary to investigate many more transgenic mice.

Epidermal growth factor (EGF) antagonizes transforming growth factor (TGF)-beta1-induced collagen lattice contraction by human skin fibroblasts

Wound contraction plays an important role in healing, but in extreme conditions, it may lead to excessive scar formation and pathological wound contracture. To date, the key regulator of excessive contracture is known to be transforming growth factor-beta (TGF-beta1). In this study, we have evaluated epidermal growth factor (EGF) antagonism in fibroblast-populated collagen lattice (FPCL) gel contraction, which has been generally used as an in vitro model thought to mimic wound contraction in vivo. As expected, TGF-beta1 treatment enhanced normal fibroblast-induced collagen gel contraction in a dose-dependent manner. In contrast, EGF did not affect normal gel formation, but significantly antagonized TGF-beta1-induced gel formation (p<0.05 at 100 ng/ml), whereas the other growth factor, platelet-derived growth factor (PDGF), did not altered either normal or TGF-beta1-induced gel contractions. Similarly, EGF treatment, but not PDGF, also significantly suppressed TGF-beta1 release that was autologously elicited by TGF-beta1 treatment (p<0.01 at 100 ng/ml). Therefore, the results suggest that EGF may negatively regulate the role of TGF-beta1 through attenuating autologous release of TGF-beta1.

Hepatoprotection by human epidermal growth factor (hEGF) against experimental hepatitis induced by D-galactosamine (D-galN) or D-GalN/lipopolysaccharide

The hepatoprotecive effects of recombinant human epidermal growth factor (hEGF) on chemically and immunologically induced experimental liver injury models were examined. The hEGF clearly decreased serum transaminase levels in D-galactosamine (D-GalN) and D-GalN/lipopolysaccharide (LPS)-induced liver injury models under sub-lethal conditions. However, it has not significantly changed either serum or in vitro tumor necrosis factor (TNF)-alpha production or in vitro nitric oxide (NO) production, suggesting that the hepatoprotection by EGF is not mediated by inhibiting these pathological mediators produced in D-GalN and D-GalN/LPS-induced liver injury.

Inhibition of lipopolysaccharide-induced I-kappaB degradation and tumor necrosis factor-alpha expression by acriflavine, an antimicrobial agent

Acriflavine neutral (ACF) has been used for treatment of microbial infections for humans and fishes. Effects of ACF on the nuclear factor-kappaB (NF-kappaB) activation and tumor necrosis factor-alpha (TNF-alpha) production by lipopolysaccharide (LPS), an endotoxin, were examined in rat and RAW264.7 cells. Gel retardation analysis revealed that LPS (1 microg/kg) activated NF-kappaB in the liver, whereas pretreatment of rats with ACF (10 mg/kg) completely prevented the NF-kappaB activation. Selectivity of the NF-kappaB DNA binding was confirmed by immunodepletion with anti-p65 and anti-p50 antibodies. Translocation of NF-kappaB to the nucleus is preceded by phosphorylation and proteolytic degradation of inhibitor-kappaBalpha (I-kappaBalpha) subunit. Whereas the level of I-kappaBalpha protein was rapidly decreased after treatment of rats with LPS (1 microg/kg), ACF treatment prior to LPS attenuated the decrease in I-kappaBalpha protein level. LPS-induced increase in the production of TNF-alpha, the principal inflammatory mediator, was prevented by ACF pretreatment by 80%. Stimulation of RAW264.7 cells with 1 microg/ml of LPS caused an increase in DNA binding activity of NF-kappaB, which was 80% inhibited by 1 microg/ml of ACF. LPS reduced I-kappaBalpha level in RAW264.7 cells by 77%. ACF attenuated LPS-induced decrease in I-kappaBalpha protein in a concentration-dependent manner. Production of TNF-alpha by LPS from RAW264.7 cells was decreased by 84% in the presence of ACF. Data showed that ACF inhibited LPS-induced NF-kappaB activation through inhibition of I-kappaBalpha degradation and TNF-alpha production in both rat and RAW264.7 cells. Inhibition of NF-kappaB activation and TNF-alpha production may be associated with the anti-inflammatory activity of ACF.

Characterization and complementation of a Pichia stipitis mutant unable to grow on D-xylose or L-arabinose

Pichia stipitis CBS 6054 will grow on D-xylose, D-arabinose, and L-arabinose. D-Xylose and L-arabinose are abundant in seed hulls of maize, and their utilization is important in processing grain residues. To elucidate the degradation pathway for L-arabinose, we obtained a mutant, FPL-MY30, that was unable to grow on D-xylose and L-arabinose but that could grow on D-arabinitol. Activity assays of oxidoreductase and pentulokinase enzymes involved in D-xylose, D-arabinose, and L-arabinose pathways indicated that FPL-MY30 is deficient in D-xylitol dehydrogenase (D-XDH), D- and L-arabinitol dehydrogenases, and D-ribitol dehydrogenase. Transforming FPL-MY30 with a gene for xylitol dehydrogenase (PsXYL2), which was cloned from CBS 6054 (GenBank AF127801), restored the D-XDH activity and the capacity for FPL-MY30 to grow on L-arabinose. This suggested that FPL-MY30 is critically deficient in XYL2 and that the D-xylose and L-arabinose metabolic pathways have xylitol as a common intermediate. The capacity for FPL-MY30 to grow on D-arabinitol could proceed through D-ribulose.

In vitro antiinflammatory effects of neolignan woorenosides from the rhizomes of Coptis japonica

Five dihydrobenzofuran neolignans, woorenosides I (1), II (2), III (3), IV (4), and V (5), isolated from Coptis japonica (Ranunculaceae), suppressed tumor necrosis factor (TNF)-alpha and nitric oxide (NuOmicron) production, as well as lymphocyte proliferation triggered by inflammatory signals such as various mitogens, in a dose-dependent manner. The results indicate that the woorenosides strongly inhibit the mitogenic response by activated macrophage and lymphocytes and suggest that these compounds may participate in regulating inflammatory processes.

Hormonal regulation of radioiodide uptake activity and Na+/I- symporter expression in mammary glands

The observation that radioiodide uptake (RAIU) activity, mediated by the Na+/I- symporter (NIS), is significantly increased in lactating breast suggests that RAIU and NIS expression in mammary gland are modulated by hormones involved in active lactation. We showed that both the NIS expression level and RAIU in rat mammary gland are maximal during active lactation compared to those in the mammary glands of virgin and pregnant rats as well as the involuting mammary gland. In the lactating mammary gland, NIS is clustered on the basolateral membrane of alveolar cells as a lesser glycosylated form than NIS in thyroid. The RAIU of lactating mammary gland was partially inhibited by treatment with a selective oxytocin antagonist or bromocriptine, an inhibitor of PRL release. These findings suggest that RAIU and NIS expression in mammary gland are at least in part modulated by oxytocin and PRL. Indeed, we showed that NIS messenger ribonucleic acid level was increased in a dose-dependent manner by oxytocin and PRL in histocultured human breast tumors.

Synthesis and structure-activity relationships of novel compounds for the inhibition of TNF-alpha production

This study describes the synthesis, in vitro evaluation and molecular modeling study of novel compounds for the inhibition of TNF-alpha production. Among these compounds, 2-[3-(cyclopentyloxy)-4-methoxyphenyl]-1-isoindolinone (9) was selected as a lead compound and its pyridine derivative 10 was more potent in activity and safer than rolipram.

Pharmacokinetic/pharmacodynamic evaluation of a novel potassium channel opener, SKP-450, in healthy volunteers

To evaluate the pharmacokinetic/pharmacodynamic characteristics of SKP-450, a novel K+ channel opener, a single blind, randomized, placebo-controlled, dose-rising, parallel-group study was conducted in 28 healthy volunteers. The volunteers were randomly allocated to dosage groups of 50 micrograms, 100 micrograms, 200 micrograms, and 300 micrograms. Single doses of SKP-450 were administered orally, after overnight fasting, and serial blood sampling and pharmacodynamic measurements were performed up to 48 hours after the drug was administered. The 200 micrograms group was further studied for food interactions in a crossover fashion. Drug concentrations in plasma were determined by HPLC. Hemodynamic changes after drug administration were evaluated by serial measurements of blood pressure (BP), pulse rate (PR), cardiac index (CI), and total peripheral resistance (TPR), using computerized impedance cardiography. Changes in plasma renin activity (PRA) and aldosterone concentrations (PAC) were determined 4 and 24 hours after drug administration. Both SKP-450 and SKP-818, an active metabolite, showed linear pharmacokinetic characteristics, and food intake did not significantly affect the pharmacokinetic characteristics of either compound. Dose-related pharmacological effects were obvious for both the 200 micrograms and 300 micrograms groups. Hemodynamic parameters related to vasodilation and reflex tachycardia, such as maximum changes in diastolic BP, PR, CI, and TPR, showed significant dose-dependent changes. The area under the time-effect curve (AUEC) of the parameters also showed a similar dose-dependent pattern. The PRA and PAC exhibited significant changes 4 hours after drug administration in the 300 micrograms group. Adverse effects, such as headaches, were more frequently observed at the higher dose levels. SKP-450 was generally well tolerated by these normotensive subjects. The antihypertensive efficacy of SKP-450 needs to be evaluated in hypertensive patients after multiple dosing.

In vitro anti-inflammatory effects of cynaropicrin, a sesquiterpene lactone, from Saussurea lappa

We investigated in vitro anti-inflammatory effects of cynaropicrin, a sesquiterpene lactone from Saussurea lappa, on tumor necrosis factor (TNF)-alpha and nitric oxide (NO) release, and lymphocyte proliferation. Cynaropicrin strongly inhibited TNF-alpha release from lipopolysaccharide-stimulated murine macrophage, RAW264.7 cells, and differentiated human macrophage, U937 cells, proved to produce notable amount of TNF-alpha. It also potently attenuated the accumulation of NO released from lipopolysaccharide- and interferon-gamma-stimulated RAW264.7 cells in a dose-dependent manner. In addition, the immunosuppressive effects of the compound on lymphocyte proliferation in response to mitogenic stimuli were examined. Cynaropicrin also dose-dependently suppressed the proliferation of lymphocytes from splenocytes and interleukin-2-sensitive cytotoxic T lymphocyte, CTLL-2 cells, stimulated by lipopolysaccharide, concanavalin A, phytohemagglutinin and interleukin-2. However, treatment with sulphydryl compound, L-cysteine, abrogated all these inhibitory effects. These results suggest that cynaropicrin may participate in the inflammatory response by inhibiting the production of inflammatory mediators and the proliferation of lymphocytes and its inhibitory effect is mediated through conjugation with sulphydryl groups of target protein(s).

Inhibitor of tumor necrosis factor-alpha production in lipopolysaccharide-stimulated RAW264.7 cells from Amorpha fruticosa

Certain flavonoids were reported to show an immunoregulatory activity against lymphocyte proliferation and cytokine production. In the course of a search for tumor necrosis factor (TNF)-alpha inhibitory compounds from natural plants, we also isolated a prenylfavanone type of flavonoid, amoradicin, from the extract of Amorpha fruticosa by activity-guided fractionation. This compound significantly inhibited TNF-alpha production in lipopolysaccharide (LPS)-stimulated RAW264.7 cells with an IC(50) value of 28.5 microM. The activity was comparable or higher than those of standard flavonoid compounds, genistein and silybin with IC(50) of 24.9 and 140.3 microM, respectively.

Expression and activity of human Na+/I- symporter in human glioma cells by adenovirus-mediated gene delivery

Radioiodide concentrating activity in the thyroid, mediated by human Na+/I- symporter (hNIS), provides a mechanism for effective radioiodide treatment for patients who have invasive, recurrent, and metastatic thyroid cancers after total thyroidectomy. In an attempt to develop hNIS gene transfer for radioiodide therapy for patients with brain tumors, we have constructed recombinant adenoviruses, rAd-CMV-hNIS9 and rAd-CMV-FLhNIS, to express exogenous hNIS in U1240 and U1240Tag human glioma cells. U1240Tag differs from U1240 glioma cells in that it expresses the SV40 large T antigen oncoprotein. In both U1240 and U1240Tag cells, radioiodide uptake (RAIU) activity in the cells infected with rAd-CMV-hNIS9 or rAd-CMV-FLhNIS increases as the adenoviral MOI increases. The protein expression profile of hNIS in infected cells is generally in agreement with their RAIU activity profile. Although the expressed hNIS9 protein appeared to have a shorter half-life than FLhNIS, hNIS9 expression could be maintained by multiple infections in these cells. In addition, we show that hNIS can be expressed and function in a xenografted human glioma by intratumoral injection of rAd-CMV-hNIS9.

Peripheral hypoechoic lesions of the prostate: evaluation with color and power Doppler ultrasound

OBJECTIVE

To assess the usefulness of color and power Doppler ultrasound in predicting the benignity and malignancy of the peripheral hypoechoic lesion of the prostate.

METHODS

Thirty-nine patients who had peripheral hypoechoic lesions on transrectal ultrasound were evaluated with color and power Doppler ultrasound followed by lesion-specific transrectal ultrasound-guided biopsies. The interpretation of color and power Doppler ultrasound was not performed separately and flow signals were categorized using a combination of the two modalities. The amount of flow signals within the lesion was evaluated and categorized into three groups: increased/equal/decreased flow compared to surrounding normal tissue on ultrasound. Doppler spectra could be obtained from the lesions in 23 patients. The amount of flow signals and resistive indexes of the spectra of the lesions were compared with those of surrounding normal tissue using the Mann-Whithney U test.

RESULTS

Transrectal ultrasound-guided biopsy of the hypoechoic lesions revealed prostate cancer in 20 patients and benign prostatic diseases in 19. Flow signals within the lesions were of increased/equal/decreased flow compared to surrounding normal tissue in 16/2/2 in the prostate cancer group and 3/9/7 in the benign disease group, respectively. The difference was statistically significant (p = 0.0003). Resistive indexes of the lesion were 0.58-1.0 (mean 0.75) in the prostate cancer group and 0.57-1.0 (mean 0.80) in the benign disease group, and there was no significant difference between the two groups (p = 0.82). If we consider an increased flow signal within a peripheral hypoechoic lesion as a sign of prostate cancer, color power Doppler ultrasound has a sensitivity of 80%, a specificity of 84%, and an accuracy of 82%.

CONCLUSION

Evaluation of peripheral hypoechoic lesions of the prostate with color and power Doppler may enhance the diagnostic capability of transrectal ultrasound.

Collision tumors of the ovary associated with teratoma: clues to the correct preoperative diagnosis

PURPOSE

Collision tumors represent a coexistence of two adjacent but histologically distinct tumors without histologic admixture in an organ. The purpose of this study was to describe the imaging findings of collision tumors of the ovary associated with teratoma and to look for clues that might lead to the correct preoperative diagnosis.

METHOD

Seven pathologically proven cases of collision tumor of the ovary associated with teratoma were retrospectively reviewed. Ovarian teratomas were coexistent with mucinous cystadenoma (n = 4), borderline mucinous tumor (n = 1), mucinous cystadenocarcinoma (n = 1), and dysgerminoma (n = 1). US (n = 5), CT (n = 3), and/or MRI (n = 4) findings were evaluated.

RESULTS

In addition to the typical findings of teratoma, the mass contained a multiloculated cystic portion filled with nonfatty fluid, suggesting the coexistent epithelial tumor in five cases. In one case, the mass contained a large solid component, suggesting the possibility of collision tumor. In the remaining one case, coexistent small mucinous cystadenoma could not be identified.

CONCLUSION

Preoperative imaging for ovarian teratoma revealed a collision tumor in six of seven cases. The possibility of a collision tumor should be considered when an ovarian teratoma has imaging findings that cannot be explained solely by an ovarian teratoma.