[In vitro activities of 23 antimicrobial agents against 4,993 gram-positive and gram-negative bacterial strains isolated from multicenter of Japan during 1994--in vitro susceptibility surveillance.Levofloxacin-Surveillance Group]

In a surveillance study conducted during 1994 at 24 medical institutes from different geographical areas of Japan, the susceptibility of clinical isolates to twenty three comparative agents, such as ofloxacin, levofloxacin, ciprofloxacin, tosufloxacin, ampicillin, clavulanic acid/amoxicillin, oxacillin, piperacillin, cefaclor, cefotiam, cefdinir, cefclidin, ceftazidime, cefpirome, imipenem, aztreonam, vancomycin, minocycline, chloramphenicol, clarithromycin, sulfamethoxazole/trimethoprim, amikacin, and gentamicin, were tested by the standard broth micro-dilution method. A total of 4,993 isolates tested in this study included Streptococcus pneumoniae, methicillin susceptible Staphylococcus aureus (MSSA), methicillin resistant Staphylococcus aureus (MRSA), coagllase negative streptococci (CNS), Enterococcus faecalis, Enterococcus faecium, Enterobactericeae, Pseudomonas aeruginosa from patients with urinary tract infections or respiratory tract infections, and Haemophilus influenzae. For MSSA, S. pneumoniae, Enterobacteriaceae, and H. influenzae, more than 70% of the isolates was susceptible to fluoloquinolones. However, resistance occurred in more than 50% of MRSA and P. aeruginosa isolated from UTI. Fluoroquinolones were found to be effective against high level penicillin-resistant S. pneumoniae, the third generation cephem-resistant Enterobacteriaceae and ampicillin-resistant H. influenzae.

Structural characterization of recombinant human erythropoietins by fluorophore-assisted carbohydrate electrophoresis

Routine analysis of the carbohydrate moieties of a glycoprotein is critical for ensuring the consistent quality of biopharmaceutical products. Fluorophore-assisted carbohydrate electrophoresis (FACE) is a recently introduced method for the separation, by polyacrylamide gel electrophoresis, of oligosaccharides labeled with 8-amino-naphthalene-1,3,6-trisulphonic acid (ANTS). In this study, we have evaluated the applicability of the FACE method to analysis of the carbohydrate moieties of three different recombinant human erythropoietins (rHuEPOs), two Chinese hamster ovary (CHO) cell-derived rHuEPOs, and one baby hamster kidney (BHK) cell-derived rHuEPO. The N-linked oligosaccharides released from the rHuEPOs were labeled with ANTS. Enzymic sequence analysis of the N-linked oligosaccharides was performed by the FACE method. The results showed that the FACE method was useful for the analysis of sialo-, asialo-, and agalacto-oligosaccharides in the same gel. Its usefulness for rapidly and reliably revealing the oligosaccharide profiles of given glycoproteins, and its reproducibility were also confirmed in this study. In conclusion, the method can be used for evaluating the quality consistency of recombinant glycoprotein products in terms of the carbohydrate moiety.

An NADPH-dependent reductase in neonatal pig testes that metabolizes androgens and xenobiotics

We have isolated an NADPH-dependent reductase from neonatal pig testes that metabolizes androgens and a variety of xenobiotics. This enzyme is distinct from 3alpha/beta,20beta-hydroxysteroid dehydrogenase or its homologue, carbonyl reductase, as judged by its immunological and molecular properties and its much narrower specificity for steroids. This reductase and 3alpha/beta,20beta-hydroxysteroid dehydrogenase may be part of a mechanism for regulating androgen levels the neonatal pig testes. Interestingly, we could not find multiple isoforms of 3alpha/beta,20beta-hydroxysteroid dehydrogenase/carbonyl reductase in pig testes unlike human and rat testes and other organs in which multiple isoforms are expressed.

N-myc gene amplification in rhabdomyosarcoma detected by fluorescence in situ hybridization: its correlation with histologic features

Fluorescence in situ hybridization (FISH) was applied to 15 alveolar rhabdomyosarcomas (A-RMSs) and 14 embryonal RMSs (E-RMSs) to detect N-myc (also called MYCN) oncogene amplification. The results were compared with histologic characteristics and clinical factors. The number of surviving patients in each subtype was 5 of 15 with A-RMS and 5 of 14 with E-RMS. N-myc amplification was detected in 9 of the 15 A-RMSs but in none of the 14 E-RMSs. Tumor cells exhibiting N-myc amplification were identified only in the alveolar area in two A-RMSs, and they demonstrated a histologic mixture of alveolar and embryonal patterns. The remaining seven cases with an amplified N-myc showed a conventional alveolar pattern. Among the 15 A-RMSs, the survival rate of patients with tumors showing nonamplified N-myc and amplified N-myc oncogene was 4 (66%) of 6 and 1(11%) of 9, respectively (P < .05). No significant difference was observed between the other clinical findings (age, primary sites, clinical stages) of the N-myc-amplified and nonamplified tumors. Therefore, we concluded that the N-myc gene amplification, which is characteristic of a particular subtype of A-RMS, might be useful as a prognostic factor for an unfavorable outcome.

Malignant melanoma imaging with Tl-201

Two patients with malignant melanoma were evaluated using Tl-201 scintigraphy. Planar scintigraphy showed tumor accumulation, and SPECT Tl-201 imaging revealed exact tumor localization. The findings indicate the utility of Tl-201 to detect the primary lesion and to identify postoperative recurrence in malignant melanoma.

Mutation of tyrosine-194 and lysine-198 in the catalytic site of pig 3alpha/beta,20beta-hydroxysteroid dehydrogenase

Pig 3alpha/beta,20beta-hydroxysteroid dehydrogenase is an NADPH-dependent enzyme that catalyses the reduction of ketones on steroids and aldehydes and ketones on various xenobiotics, like its homologue carbonyl reductase. 3alpha/beta,20beta-Hydroxysteroid dehydrogenase and carbonyl reductase are members of the short-chain dehydrogenases/reductase family, in which a tyrosine residue and a lysine residue have been identified as catalytically important. In pig 20beta-hydroxysteroid dehydrogenase these residues are tyrosine-194 and lysine-198. Here we report the effect on the reduction of two ketone and two aldehyde substrates by pig 3alpha/beta,20beta-hydroxysteroid dehydrogenase in which tyrosine-194 has been mutated to phenylalanine and cysteine, and lysine-198 has been mutated to isoleucine and arginine. Mutants with phenylalanine-194 or isoleucine-198 are inactive. Depending on the substrate, the mutant with cysteine-194 has a catalytic efficiency of 0.4-1% and the mutant with arginine-198 has a catalytic efficiency of 4-23% of the wild-type enzyme. We also mutated tyrosine-81 and tyrosine-253 to phenylalanine. Although both tyrosines are conserved in 3alpha/beta,20beta-hydroxysteroid dehydrogenase and carbonyl reductase, depending on the substrate, the mutant enzymes are as active as, or more active than, wild-type enzyme.

Reproducibility of 99Tcm-MAG3 clearance in normal volunteers with the two-sample method: comparison with 131I-OIH

The aim of this study was to evaluate the reproducibility of 99Tcm-mercaptoacetyltriglycine (99Tcm-MAG3) clearance and to compare it with that of 131I-orthoiodohippurate (131I-OIH), which is widely used in clinical practice. Twelve young healthy volunteers with a mean age of 23.4 years (range 19-28) were enrolled in the study. The investigations were repeated at an interval of 1 month under similar physiological conditions. Each volunteer received a simultaneous injection of 99Tcm-MAG3 and 131I-OIH that was commercially available in an already labelled form. Blood samples were obtained at 44 and 104 min post-injection. Clearance values were calculated using the two-sample method. The mean (+/- S.D.) change from the first to the second measurement was -7.1 +/- 11.1% for 99Tcm-MAG3 and 1.7 +/- 13.6% for 131I-OIH. There were no significant differences between the first and the second measurements of 99Tcm-MAG3 and 131I-OIH clearance, respectively. 99Tcm-MAG3 clearance was shown to be very similar to that of 131I-OIH in healthy volunteers.

Composite glandular-neuroendocrine carcinoma of the hilar bile duct: report of a case

We report herein an unusual case of a composite glandular-neuroendocrine carcinoma of the hilar bile duct. A 71-year-old Japanese woman was admitted to our hospital suffering from general fatigue, progressive jaundice, and a high fever. Computed tomography and angiography findings revealed a solid hypervascular mass in the hepatic hilus. Thus, a subsegmentectomy of the liver (S4, S5) and bile duct resection with lymph node dissection were performed. A tumor measuring 6.0 x 3.0 cm was found to be located in the bile duct of the hepatic hilus. Histologically, the tumor was composed of well-differentiated adenocarcinoma and small cell neuroendocrine carcinoma cells, with a histological transition between the two components. Grimelius' method revealed the presence of diffuse positive tumor cells in neuroendocrine carcinoma. The neuroendocrine tumor cells were also diffusely immunoreactive to chromogranin A. To the best of our knowledge, only 22 previous cases of composite glandular-neuroendocrine carcinoma in the biliary tract have been reported; however, this is the first case report of a clearly composite tumor of the hilar bile duct.

Diffusion-weighted echo-planar MRI of lacunar infarcts

We studied 35 patients with lacunar infarcts, using diffusion-weighted echo-planar imaging (DW-EPI) at 1.5 T. The relative apparent diffusion coefficient ratio (ADCR) of each lesion was calculated and lesion conspicuity on DW-EPI was compared to that on images acquired with fast fluid-attenuated inversion recovery and T2-weighted fast spin-echo sequences. Acute small infarcts (within 3 days) were identified with DW-EPI as an area of decreased ADCR (range 0.33-0.87; mean 0.67) and high signal, subacute small infarcts (4-30 days) as a high-signal or isointense areas of decreased or nearly normal ADCR (0.54-0.98; 0.73), and chronic small infarcts (> 30 days) as low- or high-signal areas of nearly normal or increased ADCR (0.97-1.92; 1.32). In three patients, small infarcts of the brain stem in the hyperacute phase (within 6 h) were seen only with DW-EPI. In five patients, fresh small infarcts adjacent to multiple old infarcts could be distinguished only with DW-EPI.

Secretory carcinoma of the breast in an elderly woman: report of a case

We herein report a case of secretory carcinoma of the breast in a 73-year-old woman. Secretory carcinoma is an extremely rare tumor and demonstrates distinctive pathologic characteristics. This tumor frequently occurs in either children or adolescents, and thus has been called juvenile carcinoma. We encountered this rare tumor in an elderly woman. Aspiration biopsy cytology was performed twice, but the cytological diagnosis was not carcinoma. Such pathologic characteristics as mild atypia, the absence of hyperchromasia, and a minimal degree of pleomorphism in the tumor cells can thus lead to a cytological misdiagnosis. An excisional biopsy was performed and secretory carcinoma was finally diagnosed. Consequently, a modified radical mastectomy (Kodama's method) was performed 7 days later. We describe this very rare tumor's clinicopathologic characteristics.

Separate histogenesis of combined hepatocellular and cholangiocellular carcinoma in two patients

Double primary liver carcinomas, i.e. hepatocellular carcinoma (HCC) and cholangiocellular carcinoma (CCC) are rare. Two patients in whom double primary liver carcinomas were surgically resected are described herein. Case 1: A 51-year-old Japanese man with chronic type B hepatitis underwent hepatectomy for primary HCC with intrahepatic metastasis. Case 2: A 67-year-old Japanese man with a history of rectal cancer and CCC underwent lateral hepatic segmentectomy for a suspected recurrence of intrahepatic CCC. Lack of direct contact between tumors, no evidence of histological transition and clearly different immunohistochemical staining for cytokeratin support a distinct histogenesis of the tumors in these two patients. The findings indicate that combined HCC and CCC can arise synchronously or metachronously as an intrahepatic double cancer.

Colour Doppler sonography of breast masses: a multiparameter analysis

OBJECTIVE

To evaluate signals from breast lesions on both colour and spectral Doppler US, and to correlate findings with angiographic and histopathological features including microvessel density.

MATERIALS AND METHODS

One hundred and sixteen breast lesions in 113 patients were evaluated with colour Doppler ultrasonography. Subjective and semi-quantitative assessment of colour signals as well as spectral Doppler analysis were performed and compared. Comparison of colour Doppler features with angiographic and histopathological findings were also carried out.

RESULTS

Subjective evaluation revealed that colour signals were more commonly found in malignant (89%) than benign (56%) lesions. Malignant lesions demonstrated a more elaborate vascular network (51%) compared to 12.5% in benign lesions. Spectral Doppler analysis revealed slightly higher specificity values for the pulsatility and resistivity indices, respectively, but lower sensitivity and accuracy values compared to qualitative assessment. Colour Doppler patterns corresponded well with angiograhic images, however, the correlation between colour Doppler parameters and microvessel density was not significant.

CONCLUSION

Despite the increased examination time required, spectral analysis does not appear to contribute significantly to the differentiation between malignant and benign breast tumours. Features such as the density, pattern and predominant site of colour signals may be more useful for the evaluation of breast lesions on colour Doppler imaging.

Carbonyl reductase activity exhibited by pig testicular 20 beta-hydroxysteroid dehydrogenase

The carbonyl reductase activity exhibited by pig testicular 20 beta-hydroxysteroid dehydrogenase (20 beta-HSD) was examined using a recombinant enzyme. Kinetic parameters were obtained for 48 carbonyl group-containing substrates, including aromatic aldehydes, aromatic ketones, cycloketones, quinones, aliphatic aldehydes and aliphatic ketones. 20 beta-HSD showed a high affinity towards quinones, such as 9,10-phenanthrenequinone, alpha-naphthoquinone and menadione (Km values of 4, 2 and 5 microM, respectively), and the substrate utilization efficiency (Vmax/Km) of the enzyme against these quinones was very high. Cyclohexanone and 2-methylcyclohexanone were also reduced with a high Vmax/Km value, but not cyclopentanone or 2-methylcyclopentanone. Various aromatic aldehydes and ketones including benzaldehyde- and acetophenone-derivatives were reduced by 20 beta-HSD. Especially, 4-nitrobenzaldehyde and 4-nitroacetophenone were reduced with high Vmax/Km values in the related compounds. The enzyme also reduced the pyridine-derivatives, 2-, 3-, and 4-benzoylpyridine, with the Vmax/Km value for 2-benzoylpyridine being the highest. 20 beta-HSD reduced aliphatic aldehydes and aliphatic ketones, but was more effective on the former. The correlation between the structure of carbonyl compounds and their substrate Vmax/Km is discussed.

Anaplastic carcinoma showing rhabdoid features combined with mucinous cystadenocarcinoma of the pancreas

A 52-year-old Japanese woman presented with complaints of back pain, loss of appetite, and weight loss; her diagnosis was a mass in the pancreatic tail. A distal pancreatectomy combined with lymph node dissection was performed. The tumor measured 10.0 x 9.5 x 8.0 cm and consisted of a cystic mass and a solid area. Histologically, the cystic mass represented a typical mucinous cystadenocarcinoma, whereas the solid portion was composed of anaplastic tumor cells with round eosinophilic intracytoplasmic inclusions, as seen in malignant rhabdoid tumor of the kidney. The hyaline-like intracytoplasmic inclusions were weakly positive for periodic acid-Schiff and were resistant to diastase. There was a gradual transition between the mucinous cystadenocarcinoma and the anaplastic carcinoma showing rhabdoid features. Additionally, the tumor cells of the anaplastic carcinoma were immunoreactive to both epithelial membrane antigen and vimentin. These findings suggest that the anaplastic carcinoma with rhabdoid features developed from the mucinous cystadenocarcinoma of the pancreas.

[Transthoracic Doppler echocardiographic detection of intramyocardial coronary artery flow in humans using high frequency transducer]

The use of transthoracic color and pulsed Doppler echocardiography to detect intramyocardial coronary artery flow in humans was evaluated in 18 normal healthy subjects (mean age 54 years) and in 16 patients with hypertrophic cardiomyopathy (HCM; mean age 59 years) to measure the intramyocardial coronary artery flow velocity at the ventricular septum and the apex using a 10-5 or 7-4 MHz transducer. Linear inflow color Doppler signals which passed the interventricular septum were demonstrated in 15 of 18 normal subjects (83%) and 15 of 16 patients with HCM (94%). The phasic flow velocities measured by pulsed Doppler echocardiography consisted of two forward flow signals in mid-systole (S-wave) and holodiastole (D-wave), and were obtained in 11 of 18 in normal subjects (61%) and 14 of 16 patients with HCM (88%). The mean peak velocities of the S- and D-waves in patients with HCM (mean [+/-SD] 27 +/- 9 and 86 +/- 23 cm/sec, respectively) were significantly (p < 0.05) higher than those in normal subjects (18 +/- 4 and 54 +/- 11 cm/sec, respectively). At the apex, linear inflow color Doppler signals which passed the myocardium perpendicularly during the whole diastole were demonstrated in 14 of 18 normal subjects (78%) and all 16 patients with HCM (100%). The phasic flow velocities were measured by pulsed Doppler echocardiography in 10 of 18 normal subjects (56%) and 15 of 16 patients with HCM (94%). The mean peak velocities in patients with HCM (74 +/- 27 cm/sec) were significantly (p < 0.05) higher than those in normal subjects (33 +/- 13 cm/sec). Transthoracic color and pulsed Doppler echocardiography can detect intramyocardial coronary artery flow in humans at the interventricular septum and the apex noninvasively.

Chronic expanding hematoma in the chest

We herein report the successful surgical treatment of 2 cases of chronic expanding hematoma in the chest. The first patient, who had undergone thoracoplasty 42 years earlier due to tuberculosis, became aware of a slowly growing mass protruding in the lateral thoracic wall. The second patient, who had tuberculous pleurisy 36 years earlier, was referred to our department because of a slowly expanding intrathoracic mass revealed by a roentgenogram. The tumors, which were encapsulated chronic hematomas, were both surgically resected. These cases are rare because of the development of a very large mass after undergoing treatment for tuberculosis more than 30 years previously.

Patterns of peripheral enhancement in breast masses: correlation of findings on contrast medium enhanced MRI with histologic features and tumor angiogenesis

PURPOSE

Our goal was to review patterns of peripheral enhancement on contrast-enhanced MRI of the breast and to correlate radiologic findings with pathologic features.

METHOD

We reviewed the MR images of 124 consecutive women with breast lesions. Peripheral enhancement was identified in 35 (32 malignant, 3 benign) lesions. MRI findings were correlated with pathologic features including microvessel density and distribution determined histologically.

RESULTS

Early peripheral enhancement with centripetal progression was seen in invasive carcinomas with a high peripheral and a low central microvessel density, associated with fibrosis and/or necrosis (n = 18; 15 with central fibrosis, 2 with fibrosis and necrosis, and 1 with necrosis alone). Early peripheral enhancement with minimal or no change in enhancement was seen in both malignant (n = 10) and benign (n = 3) lesions. Delayed peripheral enhancement with centrifugal progression was seen in carcinomas that had an expansive growth pattern and a high marginal vessel density with or without a vascularized rim of connective tissue (n = 4).

CONCLUSION

Early peripheral enhancement with centripetal progression appears to be fairly specific for carcinomas, whereas early enhancement with minimal or no centripetal progression, although more common in malignant tumors, may be seen in some benign lesions as well.

Immunochemical distribution and immunohistochemical localization of 20beta-hydroxysteroid dehydrogenase in neonatal pig tissues

Immunochemical distribution of 20beta-hydroxysteroid dehydrogenase (HSD) in neonatal pig tissues was investigated by Western blot analysis of the proteins reacting with anti-20beta-HSD antibody. 20beta-HSD was present in all organs investigated: brain, lung, thymus, submandibular gland, heart, liver, kidney, spleen, adrenal gland, testis, epididymis, prostate, vas deferens and seminal vesicle. In particular, high concentrations of 20beta-HSD were detected in the testis, followed by the kidney and liver, by the [125I]-protein A binding method. Immunohistochemical localization of the enzyme was achieved in paraffin sections of the testis, kidney, liver, epididymis, and vas deferens by the streptoavidin-biotin complex method. In the testis, very strong immunostaining was found only in interstitial Leydig cells, whereas the cells in seminiferous tubules, such as Sertoli cells and spermatogenic cells, were entirely negative. In the kidney, strong immunostaining was detected in epithelial cells of Henle's loop. The immunoreactive proteins were also localized in the hepatic lobules of the liver, tall columnar cells of the ductus epididymidis of the epididymis, and mucosal epithelium cells and muscularis of the vas deferens. These observations indicate that tissue distribution of 20beta-HSD is similar to that of carbonyl reductase in the human and rat. However, the specific and abundant expression of 20beta-HSD in testicular Leydig cells of the neonatal pig, which are concerned with the synthesis of androgens, suggests that 20beta-HSD has a very important physiological role in testicular function during the neonatal stage.

Granular cell tumors of the breast: a report of two cases

Granular cell tumors (GCT) are rare neoplasms, and only 173 cases of benign GCT of the breast have been documented. We report herein the cases of two patients with this tumor and discuss the methods of diagnosis and treatment. The first patient was a 60-year-old woman who presented with a firm ill-defined mass in her left breast. Mammography showed a dense shadow with spicula and skin thickness, and ultrasonography revealed a hypoechoic mass with an irregular border. Radical mastectomy was performed under the wrong preoperative diagnosis of breast cancer. The second patient was a 31-year-old woman who presented with an elastic-hard mass in her left breast. Mammography showed a well-demarcated dense mass, and ultrasonography revealed a well-defined hypoechoic mass with a large depth-width ratio. Fine-needle aspiration cytology (FNAC) showed a large number of histiocytic cells with abundant granular cytoplasm. An excisional biopsy was performed, and histological examination confirmed a diagnosis of GCT. GCT is benign, but often misdiagnosed as breast cancer both clinically and radiologically. Therefore, histological examination is essential for making a correct diagnosis, while FNAC is also useful. Local resection is still the treatment of choice, and surgeons should do their utmost to avoid performing needless radical mastectomy.

Breast lesions: correlation of contrast medium enhancement patterns on MR images with histopathologic findings and tumor angiogenesis

PURPOSE

To compare qualitative and quantitative magnetic resonance (MR) mammographic features of breast lesions with histopathologic findings, especially tumor angiogenesis.

MATERIALS AND METHODS

Seventy-three patients (72 women, one man; aged 30-78 years; mean age, 51.0 years) with suspicious breast lesions underwent MR imaging. Noncontrast medium-enhanced localization imaging and then gadolinium-enhanced dynamic fast spoiled gradient-recalled-echo (SPGR) imaging were performed in all patients. In selected patients, subtraction fast SPGR images were obtained. The Pearson and Spearman correlation tests were used to determine the strength of the relationships between enhancement parameters and microvessel determinations.

RESULTS

Time intensity curve type correlated with microvessel density grade (Spearman rank correlation test: r = .90, P < .001). The steepest slope of contrast medium uptake correlated with microvessel counts (Pearson correlation test; r = .83, P < .001). Peripheral enhancement in invasive carcinomas (n = 9) correlated with high peripheral and low central microvessel densities, which were associated with desmoplasia and/or necrosis. Internal septations (n = 2) were seen only in fibroadenomas.

CONCLUSION

The density and distribution of microvessels may play major roles in the determination of the initial rate of contrast medium uptake and the heterogeneity of tumor enhancement.

Accumulation of methylmalonic acid caused by vitamin B12-deficiency disrupts normal cellular metabolism in rat liver

To clarify the relationship between intracellular concentrations of methylmalonic acid and metabolic and growth inhibition in vitamin B12-deficient rats, hepatic methylmalonic acid levels were assayed and inhibition of glucose and glutamic acid metabolism by methylmalonic acid was studied in isolated hepatocytes. Vitamin B12-deficient rats (14 weeks old) excreted more urinary methylmalonic acid and had lower body weights than the control rats. Hepatic methylmalonic acid levels (3.6(SD 1.30)-5.3 (SD 0.51) mumol/g tissue; 7.9 (SD 2.90)-11.8 (SD 1.14) mM) were increased and correlated with the extent of the growth retardation during vitamin B12-deficiency. Isolated hepatocytes and mitochondria from normally fed rats were labelled with [14C(U)]glucose and [14C(U)]glutamic acid respectively, in the presence or absence of 5 mM-methylmalonic acid. Although methylmalonic acid did not affect the incorporation of 14C into protein and organic acid fractions in the hepatocytes, it inhibited 14CO2 formation (an index of glucose oxidation by the Krebs cycle) by 25% and incorporation of 14C into the amino acid fraction by 30%. In the mitochondria, methylmalonic acid inhibited 14CO2 formation (indicating glutamic acid oxidation by the Krebs cycle) by 70%, but not the incorporation of 14C into the protein fraction. The incorporation of 14C into the organic acid fraction was significantly stimulated by the addition of methylmalonic acid. These results indicate that the unusual accumulation of methylmalonic acid caused by vitamin B12-deficiency disrupts normal glucose and glutamic acid metabolism in rat liver, probably by inhibiting the Krebs cycle.

Antioxidative effect of sesamol and related compounds on lipid peroxidation

The effect of sesamol and 20 related compounds on the lipid peroxidation of liposomes induced by Fe(2)+, on the lipid peroxidation of rat liver microsomes induced by CCl(4) or NADPH and on the lipid peroxidation of mitochondria induced by ascorbate/Fe(2)+ were demonstrated. Consequently, sesamol and related compounds, such as 3-methoxy-4-hydroxyquinone, isosafrol, isoeugenol, eugenol, 3,4-methylenedioxyaniline, catechol, hydroxy-hydroquinone, 3,4-dimethoxyaniline and caffeic acid, exhibited powerful inhibitory effects on the lipid peroxidation system investigated. In particular, isoeugenol was the most powerful inhibitor among all the sesamol-related compounds tested on the lipid peroxidation system. In addition, 1,2-methylenedioxybenzene, ferulic acid, and 3,4-methylenedioxynitrobenzene were also effective on the lipid peroxidation system of liposomes induced by Fe(2)+. The correlation between the structures of sesamol-related compounds and their inhibitory effect is discussed.