Hydrophilicity of quinolones is not an exclusive factor for decreased activity in efflux-mediated resistant mutants of Staphylococcus aureus

The elevated expression of the norA gene is responsible for efflux-mediated resistance to quinolones in Staphylococcus aureus (E.Y.W. Ng, M. Trucksis, and D.C. Hooper, Antimicrob. Agents Chemother. 38:1345-1355, 1994). For S. aureus transformed with a plasmid containing the cloned norA gene, SA113(pTUS20) (H. Yoshida, M. Bogaki, S. Nakamura, K. Ubukata, and M. Konno, J. Bacteriol. 172:6942-6949, 1990), and an overexpressed mutant, SA-1199B (G.W. Kaatz, S.M. Seo, and C.A. Ruble, J. Infect. Dis. 163:1080-1086, 1991), the MICs of norfloxacin increased 16 and 64 times compared with its MICs for the recipient and wild-type strains, SA113 and SA-1199, respectively. MICs of CS-940, however, increased only two and eight times, even though these two fluoroquinolones are similarly hydrophilic (apparent logPs of approximately -1). No good correlation was found, among 15 developed and developing quinolones, between the increment ratio in MICs and hydrophobicity (r = 0.61). Analysis of the quantitative structure-activity relationship among 40 fluoroquinolones revealed that the MIC increment ratio was significantly correlated with the bulkiness of the C-7 substituent and bulkiness and hydrophobicity of the C-8 substituent of fluoroquinolones (r = 0.87) and not with its molecular hydrophobicity (r = 0.47). Cellular accumulation of norfloxacin in SA-1199B was significantly lower than that in SA-1199, and it was increased by addition of carbonyl cyanide m-chlorophenyl hydrazone. On the other hand, accumulations of CS-940 in these strains were nearly identical, and they were not affected by addition of the protonophore.

The effects of N-methyl-D-aspartate (NMDA) and its competitive antagonist, 3-(2-carboxypiperazine-4-yl)propyl-1-phosphonic acid (CPP), injected into caudate-putamen on kindled amygdaloid seizures in rats

N-methyl-D-aspartate (NMDA) is an agonist of NMDA receptors and 3-(2-carboxypiperazine-4-yl)propyl-1-phosphonic acid (CPP) is an NMDA receptor antagonist. NMDA (1 or 2 nmol per side) or CPP (2.5 or 10 nmol per side) was injected into the bilateral caudate-putamen of amygdaloid-kindled rats. In addition, CPP (10 nmol) was ipsilaterally or contralaterally injected into the unilateral caudate-putamen. Either 20 min after NMDA or 60 min after CPP, the kindled amygdala was stimulated at the generalized seizure triggering threshold. In a few animals tested, injection of NMDA into the bilateral caudate-putamen produced transient spiking activity, with no clinical manifestations. This feature began about 5 min after the injection and lasted about 10 s. When these animals were excluded from the statistical analysis, NMDA in the caudate-putamen showed a weak and non-significant anticonvulsant action. Injection of CPP into the bilateral caudate-putamen caused no ictal change, but markedly suppressed the kindled seizures. Injection of CPP into the unilateral caudate-putamen, regardless of the site, did not cause any ictal change, or affect the stimulation of the amygdala. These findings suggest that: (1) NMDA receptors in the caudate-putamen facilitate the development of kindled amygdaloid seizures; (2) activation of NMDA receptors in the bilateral, but not in the unilateral, caudate-putamen is required for the generalization and expression of kindled amygdaloid seizures.

Inhibition of mucosal lipid hyperoxidation by green tea extract in 1,2-dimethylhydrazine-induced rat colonic carcinogenesis

Phosphatidylcholine hydroperoxide (PCOOH) measured using a chemiluminescence detector to examine colonic mucosal lipid hyperoxidation increased after injection of 1,2-dimethylhydrazine and green tea extract (GTE), which we previously showed inhibited carcinogenesis and oxidative DNA damage in the gastrointestinal tract. Therefore, the hyperoxidation of membrane phospholipids reflected well the degree of DNA damage and carcinogenic alteration, and may be a useful intermediate biomarker for initiation of carcinogenesis.

Distinct distribution of protein disulfide isomerase family proteins in rat tissues

We investigated the distribution of protein disulfide isomerase (PDI) family proteins PDI, ERp72, and ERp61 in rat tissues and compared their localization by immunohistochemical double staining. The extent of their expression was diverse in different cell types, although they were ubiquitously distributed in a wide variety of cell types. Prominent staining for all three proteins was detected in thyroid follicular epithelia, tracheal mucous gland cells and chondrocytes, and chief cells and mucous neck cells of the stomach. Hepatocytes, neuronal cells in brain and spinal cord, and pancreatic acinar cells were also consistently and uniformly stained, but with low intensity. On the other hand, distinct differences were observed for the expression of the three proteins in plasma cells, pancreatic islet cells, goblet cells, and Paneth's cells of intestines, seminiferous epithelia, and salivary gland ductal epithelia. The similarities and differences in the distribution of the three proteins provide helpful clues to their biological functions.

Inhibitory effects and toxicity of green tea polyphenols for gastrointestinal carcinogenesis

BACKGROUND

Recently, and epidemiologic study showed a lower risk of gastrointestinal carcinogenesis in green tea drinkers. An experiment on two-stage skin carcinogenesis in mice showed that (-)-epigallocatechin gallate (EGCG), one of the main constituents of green tea, inhibited tumor formation.

METHODS

The inhibitory effects of EGCG and green tea extract (GTE) on N-ethyl-N'-nitro-N-nitroguanidine (ENNG)-induced duodenal carcinogenesis in the mouse, N-methyl-N'-nitro-N-nitrosoguanidine (MNNG)-induced carcinogenesis of the glandular stomach in the rat, and azoxymethane-induced colon carcinogenesis in the rat were examined. The toxicity of GTE was assessed experimentally and GTE was applied clinically in normal volunteers to determine the effective dose and to assess its harmful effects.

RESULTS

EGCG and GRE inhibited chemical carcinogenesis of the gastrointestinal tract in rodents. Judging from the epidemiologic and experimental findings, it was determined that 1 g per day of GTE might be an effective dose. GTE was not toxic and no harmful effect was found during its clinical use.

CONCLUSIONS

These findings suggest that EGCG and GTE are useful in preventing gastrointestinal carcinogenesis, and the clinical usefulness of GTE, which has no harmful effects and is inexpensive, should be studied further.

Anticonvulsant action of metabotropic glutamate receptor agonists in kindled amygdala of rats

1S,3R-1-Aminocyclopentane-1,3-dicarboxylate (1S,3R-ACPD) and L-2-amino-4-phosphonobutyrate (L-AP4) are selective agonists of metabotropic glutamate receptors (mGluRs). 1S,3R-ACPD (200 nmol) injected into the amygdala (AM) of non-kindled rats produced immediate and transient seizures, characterized by immobility, searching, and wet-dog shakes. However, this ictal response was not observed in AM-kindled rats. Intra-AM injection of 1S,3R-ACPD (40 or 200 nmol) or L-AP4 (200 nmol) resulted in a delayed and marked suppression of kindled seizures, 3 days after 40 nmol of 1S,3R-ACPD, 1 day after 200 nmol of 1S,3R-ACPD, and from 1 to 3 days after 200 nmol of L-AP4. These and the previous findings suggest that: (1) the excitatory action of 1S,3R-ACPD in the AM, which may be mediated by the postsynaptic mGluRs, is reduced after completion of kindling; (2) 1S,3R-ACPD and L-AP4 exert anti-convulsant action in the AM, presumably by activating the presynaptic as well as postsynaptic mGluRs.

[Particle Induced X-ray Emission (PIXE) for analysis of trace elements in biological materials]

Outline of Particle Induced X-ray Emission (PIXE) and its application to biomedical samples are described. Charged particles from cyclotron or van de Graaff generator bombards analytical samples and semiconductor detector measures energy and intensity of induced characteristic x-ray. Simultaneous determination for 22Na to 92U is possible by PIXE. 100 nA of 3 MeV protons bombards biomedical samples and detection limits for almost all trace essential elements are sub microgram/g. Only 1 mg of biomedical sample is necessary for determination of trace elements and no chemical procedure is necessary for preparation of analytical sample. PIXE is powerful tool for determination of essential elements and applied for diagnosis for several diseases.

Evaluation of antitumor activities of hyaluronate binding antitumor drugs: synthesis, characterization and antitumor activity

To enhance the selective delivery of antitumor drugs into regional lymph nodes and cancerous tissues via a hyaluronate (HA) receptor (CD44), we synthesized HA-mitomycin C complex and HA-epirubicin complex. To investigate the specific distribution of HA into regional lymph nodes and to evaluate the HA receptor on lewis lung carcinoma cells, we also synthesized 14C-labelled HA and fluorescent HA (FR-HA). The metabolic studies of 14C-HA and HA-epirubicin complex were performed in rats. The specific distribution of both compounds to the lymph nodes were observed after sc treatment. Internalization mechanisms of HA into carcinoma cells (lewis lung carcinoma) via HA receptor was investigated using fluorescent HA (FR-HA) in vitro. Internalization of FR-HA following binding to the cell surfaces was observed. HA-Mitomycin C (MMC) exhibited potent anti-metastatic effects against lewis lung carcinoma implanted in mice at an extremely low dose (0.01 mg/kg) whereas free MMC had no effects.

Liposome-entrapped phenytoin locally suppresses amygdaloid epileptogenic focus created by db-cAMP/EDTA in rats

Status epilepticus was induced in rats by injecting a combination of dibutyryl-cAMP (db-cAMP) and ethylenediaminetetraacetic acid (EDTA) into the amygdala (AM), and the effect of phenytoin (PHT), entrapped in liposomes (PHT-L) and given intravenously at 40 mg/kg, on the spiking activity of the AM epileptogenic focus was examined. Electroencephalograms were recorded from the db-cAMP/EDTA-injected AM and the bilateral sensorimotor cortices. One dose of PHT-L, given 30 min after intra-AM db-cAMP, produced immediate and transient seizure suppression, but did not suppress the sequential spiking activity, which lasted for more than 5 h. In contrast, two doses of PHT-L, given 30 and 60 min after intra-AM db-cAMP/EDTA, produced delayed and local suppression of AM discharges, and immediate and transient seizure suppression was also observed. The AM discharges began to be suppressed about 100 min after the second injection of PHT-L injection, with no overt change occurring in cortical spiking activity. This was followed by total seizure suppression about 170 min after the second PHT-L injection. This effect was not observed after one or two injections of PHT alone. When horseradish peroxidase (HRP), to which the blood-brain barrier is impermeable, was entrapped in liposomes (HRP-L) and given intravenously 30 min after intra-AM db-cAMP/EDTA, an accumulation of HRP was found in the db-cAMP/EDTA-injected AM in 2 of the 5 animals tested. With 2 doses of HRP-L given 30 and 60 min after intra-AM db-cAMP/EDTA, the local augmentation of HRP in the AM was found in all 5 of the 5 animals tested. Our findings suggest that: (1) the AM epileptogenic focus created by db-cAMP/EDTA has a high affinity for liposomes, and this factor participates in the local suppression of AM discharges by PHT-L, and (2) two injections of PHT-L are required for the AM to gather an effective amount of PHT-L.

Effect of 2-hydroxypropyl-beta-cyclodextrin on percutaneous absorption of methyl paraben

A potential use of 2-hydroxypropyl-beta-cyclodextrin (HP-beta-CyD) to solubilize methyl paraben and to suppress its percutaneous absorption was examined, and compared with nonionic surfactant HCO-60. HP-beta-CyD significantly increased the solubility of methyl paraben in water, where the apparent 1:1 stability constant of the soluble complex was determined to be 2150 M-1. The in-vitro cutaneous permeability of methyl paraben through an isolated skin of hairless mouse was suppressed by HP-beta-CyD, thus promoting the bioconversion of methyl paraben to the less toxic metabolite, p-hydroxybenzoic acid (p-HBA) in the epidermis. These effects of HP-beta-CyD were greater than those of HCO-60. HP-beta-CyD (2% w/v) reduced the in-vivo percutaneous absorption of methyl paraben by 66% 24 h after the topical application of a solution containing [14C]methyl paraben to hairless mouse skin. Additionally, the percutaneous absorption of [14C]HP-beta-CyD was confirmed to be extremely low. These results suggest that HP-beta-CyD is useful in liquid preparations of methyl paraben for topical application.

[A case report of acute aortic dissection with aortic regurgitation and cardiac tamponade: intimal tear just above commissure of right coronary cusp and left coronary cusp]

A 57-year-old man with acute dissecting aneurysm of the ascending aorta underwent immediate operation. Preoperative study showed aortic regurgitation and cardiac tamponade. The intimal tear originated just above commissure of right coronary cusp and left coronary cusp. The procedure was a combination of direct closure of the entry and dissecting space and resuspension of native aortic valve. It was preferential of simple intervention limited to the ascending aorta without using prosthesis. There was no complication such as aortic valve regurgitation, enlargement of the ascending aorta, or persistent of dissection during follow-up period of 12 months.

[Clinical evaluation of enzyme immuno assay systems for HCV antibody--synthetic peptide antigen and recombinant antigen]

To evaluate the frequency of the false positive results, we examined 168 patients for the presence of HCV using two HCV antibody assay systems, Synpep HCV-EIA (Synpep) and Abbott EIA II (Abbott). The results obtained by the two methods were significantly different in 22 patients. Cases in 17 of these patients, the results were positive with Abbott but negative with Synpep, and there were no clinical signs or delectable virus RNA. However, in 2 cases, the results were markedly positive with Abbott and weakly positive with Synpep. The presence of virus RNA and the increase of transaminase were observed in one case but both were noted in the other case. The serum of these two patients reacted with the C33C and C22-3 regions in RIBA II. We observed another 2 cases in which the elevation of the cut-off index with Synpep preceded that with Abbott at the early stage of acute hepatitis C. We also compared the cut-off index with the histology activity index (HAI) score determined by liver biopsy. The average cut-off index with Synpep was proportional to the HAI score in the range between 0 and 13. Based on the cut-off index/HAI score relationship, we suggest that patients with inactive chronic hepatitis show a Synpep cut-off index less than 11.

HLA class II genotyping by polymerase chain reaction-restriction fragment length polymorphism method (PCR-RFLP) in systemic lupus erythematosus patients

Recently, genotyping of HLA class II alleles by digestion of polymerase chain reaction (PCR) amplified polymorphic DNA region with restriction endonucleases (PCR-RFLP) has been reported and claimed to be a simple and reliable technique. We tested the use of PCR-RFLP for genotyping of DQA 1, DQB 1, DPB 1 and DRB 1 alleles of 40 normal individuals and 19 patients with systemic lupus erythematosus (SLE). In agreement with previous reports, we observed an association of SLE with the DRB 1*1501-DQA 1*0102-DQB 1*0602 haplotype and noted an unreported association with DPB 1*0501. Although these observations must be confirmed with larger sample sizes, we believe that the PCR-RFLP is simpler and more practical than the sequence-specific oligonucleotides (PCR-SSO) for genotyping and can be invaluable to the more widespread molecular determination of HLA-class II specificities, including in non-specialized laboratories.

Pulmonary oncocytoma: report of a case in conjunction with an immunohistochemical and ultrastructural study

An intra-pulmonary mass in a 51 year old Japanese woman was incidentally discovered in the right middle lobe. The resected tumor was grossly well-demarcated, solid, light yellowish white in color and measured 3.0 x 2.0 x 1.5 cm in size. It was composed of a diffuse proliferation of large polygonal cells with an abundant, granular cytoplasm, and round to irregular nuclei with prominent nucleoli. Smaller eosinophilic cells with hyperchromatic nuclei and larger vacuolated cells were also observed. However, no mucin production was detected. There were neither argyrophilic nor argentaffin cells, and no serotonin-positive cells. They showed an immunoreactivity to cytokeratin and vimentin but not to alpha-actin. On electron microscopy, abundant microvilli, which have never been previously described in pulmonary oncocytomas, were observed. Occasional desmosomes and myelin figures as well as numerous mitochondria were also seen. No neurosecretory granules were present. These findings suggested that this tumor might have an epithelial origin from the bronchial serous gland with subsequent cellular degeneration.

[Detection of heterogeneous MRSA by using the PCR method and population analysis]

To assess the clinical usefulness of the PCR method for the detection of methicillin-resistant Staphylococcus aureus (MRSA) by targetting the mecA gene, we surveyed 150 clinical isolates of Staphylococcus aureus and compared the results of the PCR method with those of the standard broth microdilution method. Fifty-four isolates (36%) were positive for the mecA gene and two of them, presenting coagulase type IV, were recognized as susceptible strains by microdilution method, while all the other mecA positive strains were drug-resistant. Population analysis revealed that these two strains were heterogeneous in terms of drug-resistance and composed of two populations of cells; i.e., relatively susceptible cells and highly resistant cells. The discrepancy between the phenotypic expression (drug-resistance) and the genotype (mecA gene) seems to be due to the small percentage of highly resistant cells. Drug-resistant colonies could be induced in these strains by the contact with methicillin, indicating the selective increase of the population of resistant cells by a passage in the drug. These observations suggest that it is clinically important to detect the resistance-inducible strains (prototype MRSA) by using the PCR method and population analysis.

[A case of pulmonary hyalinizing granuloma with its occupational history of dust exposure]

Multiple pulmonary nodules were found in a patient who had an occupational history of coal mining for eleven years and road construction for fifteen years. An open lung biopsy was performed, because nodules had increased in size compared to previous ones and a trasbronchial biopsy was not diagnostic. The nodules were composed of dense concentric lamellar collagenous structures with a serpentine pattern surrounded by an infiltration of histiocytes, lymphocytes and plasma cells with Russel bodies. These findings are compatible with pulmonary hyalinizing granuloma (PHG) named by Liebow A. A. The etiopathogenetic mechanism and the difference between PHG and silicotic nodule is discussed.

[Portal hemodynamic changes from TIPS--evaluation with pulse Doppler method]

Transjugular intrahepatic portosystemic shunt (TIPS) was applied in three patients with Child C liver cirrhosis. Portal venous pressure was reduced by an average of 10.7 mmHg, and results such as the disappearance of esophageal varices and reduction in ascites were obtained. The portal hemodynamics of these three patients was observed before and after TIPS using the pulse Doppler method. When portal hemodynamics in the main portal vein was examined before TIPS, it was found that the mean blood flow velocity had decreased, the blood flow volume was reduced and the cross-sectional area of the vein had increased. The congestion index was high and there was definite congestion of the portal venous system. After TIPS, the blood flow velocity and volume increased, the cross-sectional area of the vein was reduced and the congestion index was lower. Congestion of the portal venous system was improved in these three patients and the clinical efficacy of TIPS was proven by these results. If the stent can be detected sonographically, stent patency is easily confirmed with the pulse Doppler method which is usefull examination technique for follow-up of patients undergoing TIPS.

Ca(2+)-ATPase distributes differently in cardiac sarcolemma than dihydropyridine receptor alpha 1 subunit and Na+/Ca2+ exchanger

We have investigated the distribution of the sarcolemmal Ca2+ transporters in hamster and dog ventricular myocytes by immunocytochemical and membrane fractionation techniques. The data suggest that the DHP receptor alpha 1 subunit and the Na+/Ca2+ exchanger are present in surface sarcolemma as well as T-tubule membranes located at the cardiac dyads. Compared with these Ca2+ transporters, the sarcolemmal Ca(2+)-ATPase is much less abundant in the latter fraction. Thus the sarcolemmal Ca(2+)-ATPase seems to be located predominantly in surface sarcolemma.

Clinical applications of Lin's forceps in flexible hysteroscopy

Eighty-one patients underwent directed biopsy with a large Lin's biopsy forceps during flexible hysteroscopy performed without cervical dilatation or anesthesia. Ninety-seven specimens were obtained, with an average size of 74.5 3(. For control study, 18 women underwent directed biopsy with a small conventional biopsy forceps. Nineteen specimens were obtained, with average size 3.4 mm3( (p <0.05). In eight women, lost intrauterine devices were retrieved with a large Lin's grasping forceps, which can easily grasp the device directly and remove it during flexible hysteroscopy.