Thrombospondin-2 (TSP2) expression is inversely correlated with vascularity in glioma

Thrombospondins (TSPs) are angiostatic factors in various cancers. However, the significance of TSPs has not been well characterised in glioma. We examined TSP1, TSP2 and vascular endothelial growth factor (VEGF) gene expression by reverse transcription-polymerase chain reaction (RT-PCR) in 37 gliomas. Thirty of the 37 glioma specimens showed VEGF gene expression. Eighteen of the 37 gliomas expressed the TSP1 gene. Seven gliomas lacked TSP2 gene expression, while the other 30 expressed TSP2. The lack of TSP2 gene expression was significantly associated with higher histological grade (Fisher's test, P = 0.0019) and increased vessel counts and density (Student's t-test, P < 0.0001), while there were no correlations between TSP1 and VEGF gene expression and clinicopathological features. These results indicate that the lack of TSP2 gene expression is a potent factor for enhancement of angiogenesis in glioma.

How BCG led to the discovery of immunostimulatory DNA

The concept of immunostimulatory DNA was borne in a long series of studies on BCG-mediated tumor resistance. DNA purified from BCG inhibited the growth of various syngeneic animal tumors, augmented NK cell activity and induced IFN-alpha/beta and -gamma from mouse spleen cells and human PBL. Extending the lines of study, we found two biologically remarkable facts that (i) DNAs from invertebrates, but not from vertebrates and plants, showed the above-mentioned biologic activities, and (ii) the activities were completely dependent on particular base sequences having CpG motifs but in a senseless manner. Details of those early studies carried out mainly in the 1980's have been reviewed in the first part of this paper. In the middle part of this review, the results of toxicity and pharmacology studies and clinical trials of BCG- DNA, performed by other groups in Japan in the late 1980's, were introduced. Since a large amount of DNA had never been administered repeatedly into experimental animals or human, those experiences obtained seem to be worthwhile to introduce. Research interests of immunostimulatory DNA were galvanized in 1995 by the report of Krieg et al. showing murine B cell activation with bacterial DNA containing CpG motifs. Within a short period of time, a huge number of papers have been published in this field, and the study has expanded rapidly and largely. Now, it includes a number of research fields, for example, host-defense mechanisms against infection, allergy, autoimmune diseases, cytokine networks, plasmid vaccination, and therapeutic application of certain diseases. This paper reviewed briefly recent advances of immunostimulatory DNA research. The response of higher animals against immunostimulatory DNA must be the most primitive but important mechanism for self-nonself discrimination against foreign DNA. By utilizing immunostimulatory DNA or controlling this primitive response, it seems possible to offer many beneficial means to human health. For instance, more potent peptide- or plasmid- vaccines could be developed by the use of immunostimulatory DNA. On the other hand, many study results suggest that immunostimulatory DNA works either beneficially or harmfully for the hosts. We assume that further extensive and careful studies are required.

Expression pattern of vascular endothelial growth factor isoform is closely correlated with tumour stage and vascularisation in renal cell carcinoma

Vascular endothelial growth factor (VEGF) has five isoforms (VEGF206, 189, 165, 145 and 121). Increased VEGF expression in renal cell carcinoma (RCC) is associated with angiogenesis, but, it is not apparent which isoform is involved in this effect. We examined the isoform patterns of VEGF by reverse transcription-polymerase chain reaction (RT-PCR) in 47 RCCs. All showed increased VEGF expression as compared with extraneoplastic renal tissue. Four of the 47 RCCs showed VEGF121 alone, 10 showed VEGF121 + 165, and 33 showed the VEGF121 + 165 + 189 pattern. Patients with pathological stage pT3-4 RCC showed the VEGF121 + 165 + 189 isoform pattern at a significantly higher incidence (10/10, 100%) than those with pT0-2 (23/37, 62%) (P < 0.022). The VEGF121 + 165 + 189 isoform pattern was also significantly associated with high vessel counts and density (P = 0.0002, Mann-Whitney U test). These observations suggested that the VEGF189 mRNA isoform is closely associated with angiogenesis and results in the growth of RCC.

Expression of the thrombospondin 1 receptor CD36 is correlated with decreased stromal vascularisation in colon cancer

Vascularisation is determined by the balance between various angiogenic and angio-inhibitory factors in cancer stroma. CD36 is a cell adhesion receptor shown to interact with the ligand thrombospondin 1 (TSP1). It has not been determined whether the interaction of TSP1 and its receptor CD36 is correlated with vascularisation or clinical outcome of malignant tumours in vivo. We studied the correlations between expression of TSP1, CD36 and vascularisation and prognosis in 65 colon cancers. Various levels of TSP1 gene expression were observed in 27 of 65 colon cancers. CD36 expression was detected in 33 of 65 cancers, and was significantly correlated with decreased stromal vascularisation (P<0.001). The colon cancers expressing CD36 showed better prognosis (P<0.01). TSP1 expression levels did not affect CD36 expression. These results suggested that CD36 expression which decreased stromal vascularisation is correlated with better prognosis of colon cancer.

Thrombospondin 2 expression is correlated with inhibition of angiogenesis and metastasis of colon cancer

Two subtypes of thrombospondin (TSP-1 and TSP-2) have inhibitory roles in angiogenesis in vitro, although the biological significance of these TSP isoforms has not been determined in vivo. We examined TSP-1 and TSP-2 gene expression by reverse transcription polymerase chain reaction (RT-PCR) analysis in 61 colon cancers. Thirty-eight of these 61 colon cancers were positive for TSP-2 expression and showed hepatic metastasis at a significantly lower incidence than those without TSP-2 expression (P = 0.02). TSP-2 expression was significantly associated with M0 stage in these colon cancers (P = 0.03), whereas TSP-1 expression showed no apparent correlation with these factors. The colon cancer patients with TSP-2 expression showed a significantly low frequency of liver metastasis correlated with the cell-associated isoform of vascular endothelial growth factor (VEGF-189) (P = 0.0006). Vascularity was estimated by CD34 staining, and TSP-2(-)/VEGF-189(+) colon cancers showed significantly increased vessel counts and density in the stroma (P < 0.0001). TSP-2(-)/VEGF-189(+) colon cancer patients also showed significantly poorer prognosis compared with those with TSP-2(+)/VEGF-189(-) (P = 0.0014). These results suggest that colon cancer metastasis is critically determined by angiogenesis resulting from the balance between the angioinhibitory factor TSP-2 and angiogenic factor VEGF-189.

Hammerhead ribozyme specifically inhibits mutant K-ras mRNA of human pancreatic cancer cells

We have evaluated the efficacy of an anti-K-ras hammerhead ribozyme targeted against GUU-mutated codon 12 of the K-ras gene in a cell-free system as well as in cultured pancreatic carcinoma cell lines. In the cell-free system, the anti-K-ras ribozyme specifically cleaved K-ras RNA with GUU-mutation at codon 12, but not other triplet sequences at codon 12 of K-ras RNA. In the cell culture system, the anti-K-ras ribozyme significantly reduced K-ras mRNA level (GUU-mutated codon 12) in Capan-1 pancreatic carcinoma cells, but less significantly suppressed K-ras mRNA in Capan-2 (GUU/GGU heterozygous-mutation at codon 12) or MIA PaCa-2 (UGU-mutated codon 12) pancreatic carcinoma cells. The ribozyme inhibited proliferation of transfected Capan-1 cells. These results suggest that this ribozyme selectively recognizes single-base mutation of K-ras mRNA and is able to reverse the malignant phenotype in human pancreatic carcinoma cells.

Multidrug resistance-associated protein and mutant p53 protein expression in non-small cell lung cancer

Multidrug resistance-associated protein (MRP) is one of the major factors for non-P-glycoprotein (PGp)-mediated multidrug resistance. We reported previously that overexpression of the MRP gene was related to the prognosis of non-small cell lung cancer (NSCLC). It is unclear how MRP expression is regulated in NSCLC. In this study, we examined MRP and mutant p53 expression in 107 NSCLCs by immunohistochemical procedures. Forty-seven (43.9%) of these 107 NSCLCs were positive for MRP in the cytoplasm. Mutant p53-positive NSCLC showed a significant correlation with MRP overexpression (P=.011). Coexpression of MRP and p53 in the same cells of NSCLC was confirmed by double-staining procedures. Twenty-six patients with MRP-positive tumors who underwent postoperative chemotherapy with MRP-related anticancer drugs (vindesine and etoposide) had significantly poorer prognoses than did those with MRP-negative tumors (P=.017). This correlation between MRP expression and prognosis was also seen in Stage III patients (P=.022) and in patients with squamous cell carcinoma (P=.062). NSCLC patients with coexpression of MRP and p53 showed poorer prognoses than did those without MRP and p53 (P=.014). These results suggested that MRP overexpression affected by mutant p53 had a significant effect on prognosis through atypical non-PGp-mediated multidrug resistance in NSCLC.

Alterations in tumour suppressor gene p53 correlate with inhibition of thrombospondin-1 gene expression in colon cancer cells

If activation of the p53 gene is involved in the progression or metastasis of colon cancer, it may affect the angiogenic phenotype in vivo. To verify this hypothesis, we studied the correlation between p53 accumulation and expression of thrombospondin-1 (TSP1) in colon cancer specimens. Levels of TSP1 gene expression were estimated by Northern blotting in 65 colon cancers. Accumulation of p53 and the distribution of TSP1 protein were evaluated immunohistochemically. Various levels of TSP1 gene expression were seen in colon cancers, while p53 accumulation was confirmed in 42 of the 65 colon cancers. The level of TSP1 gene expression demonstrated a significant inverse correlation with p53 accumulation in colon cancer. Colon cancer cells expressed TSP1 protein and p53 accumulation reciprocally in the same nests. These results suggest that alterations in the tumour suppressor gene p53 may inhibit TSP1 expression in colon cancer.

Growth stimulation of non-small cell lung cancer xenografts by granulocyte-macrophage colony-stimulating factor (GM-CSF)

Granulocyte-macrophage colony-stimulating factor (GM-CSF) has been suggested to be involved in the carcinogenesis of some types of tumours by autocrine or paracrine mechanisms. We examined GM-CSF/GM-CSF receptor (GM-CSFR) gene expression in 20 human non-small cell lung cancer (NSCLC) xenografts. The stimulatory effects of GM-CSF were examined using GM-CSF transgenic severe combined immunodeficient (SCID) mice (GM-Tg-SCID), which produce abundant human GM-CSF. A NSCLC xenograft (LC11-JCK), expressed GM-CSFR but not GM-CSF, and showed more rapid growth in GM-Tg-SCID than non-GM-CSF transgenic SCID mice (non-Tg-SCID). GM-CSF gene expression was detected in 48 of 90 (53%) primary NSCLC human specimens and GM-CSFR gene expression was detected in 42 specimens (47%). GM-CSF expression was detected in 13 of 30 squamous cell carcinoma specimens (43%) and GM-CSFR expression was detected in 10 specimens (33%). Patients with squamous cell carcinoma coexpressing GM-CSF and GM-CSFR showed significantly poorer prognosis than those expressing neither GM-CSF nor GM-CSFR (P < 0.05, Cox-Mantel test). These results suggest that GM-CSF can have a stimulatory effect on some NSCLC.

Establishment of an adrenocortical carcinoma xenograft with normotensive hyperaldosteronism in vivo

We established a xenograft line of human adrenocortical carcinoma (ADR-1), and analyzed the hyperaldosteronism induced by the xenograft in vivo. Adrenocortical carcinoma specimens from a 25-year-old woman were subcutaneously inoculated into nude mice (BALB/c-nu/nu) followed by serial passages in vivo. ADR-1 retained the histopathological features (trabecular and sinusoid nests) seen in the primary carcinoma. The patient showed hyperaldosteronism (serum aldosterone >4000 pg/ml) and hypokalemia (serum K 2.1 mEq/l), but did not show hypertension. The nude rat (F344-rnu/rnu) bearing ADR-1 showed hyperaldosteronism (serum aldosterone 3320+/-1420 pg/ml; control 191+/-130 pg/ml) and hypokalemia (serum K 3.4+/-0.4 mEq/l; control 5.2+/-1.0 mEq/l) in vivo, and hypertension was not obvious. ADR-1 was shown immunohistochemically to retain production of human-specific corticosteroid synthetase. The xenograft ADR-1 will be useful to elucidate the regulatory mechanism of normotensive hyperaldosteronism.

Brain-specific angiogenesis inhibitor 1 expression is inversely correlated with vascularity and distant metastasis of colorectal cancer

Brain-specific angiogenesis inhibitor (BAI) 1 was recently isolated as a novel p53 inducible gene. BAI1 has been suggested to play a significant role in angiostasis. We studied the expression of BAI1 in 49 colorectal cancer specimens by RT-PCR. BAI1 expression was significantly reduced in colorectal cancers as compared to the extraneoplastic tissues (X(2) test, p=0.041). BAI1 expression was inversely correlated with vascular invasion and metastasis (Fisher's exact test, p 0.045). Moreover, vascularity in the colorectal cancer was inversely correlated with BAI1 gene expression (Mann-Whitney U-test, p=0.0003). These observations suggested that BAI1 expression might inhibit angiogenesis and metastasis of colorectal cancer.

Increased expression of human histocompatibility leukocyte antigen-G in colorectal cancer cells

Human histocompatibility leukocyte antigen (HLA)-G is a nonclassical major histocompatibility complex class I molecule. HLA-G is known to provide tolerance from recognition by natural killer cells. We studied HLA-G expression in 39 human colorectal cancers and 23 extra-neoplastic colon tissue samples by RT-PCR. The expression of HLA-G mRNA was significantly more frequent in colorectal cancer (34 of 39 cases) than in the extraneoplastic tissue (10 of 23 specimens; chi2 test, p = 0.0003). HLA-G expression was also confirmed on the cancer cells immunohistochemically. These results suggested that HLA-G on colorectal cancer cells may be correlated with escape from immunological surveillance during colon cancer development.

Aberrant isoform of vascular endothelial growth factor 189 expression is correlated with xenotransplantability of human esophageal cancer

Xenografted neoplastic tissues are often utilized to study biology of human cancer. We studied isoform pattern (VEGF206, VEGF189, VEGF165, VEGF121) of an angiogenic factor VEGF in both esophageal primary cancers and cancer xenografts by RT-PCR analysis. Eighteen of 19 (95%) xenografts showed the cell associated aberrant isoform of VEGF189 at a significantly higher incidence than 19 of 31 (61%) primary cancers (P=0.009, Fisher's exact test). These observations suggested that the aberrant isoform of VEGF189 mRNA affects the xenotransplantability of human esophageal cancer.

Novel angucycline compound with both antigastrin- and gastric mucosal protective-activities

An angucycline series compound P371 A1 (1) from Streptomyces sp. P371 was established to have a novel structure comprising an ureido group at one of four sugar units on the basis of 2D NMR techniques. 1 exhibited an inhibitory activity against the pentagastrin-stimulated acid secretion as well as protective activities against HCl/ethanol- and indomethacin-induced gastric lesions.

Familial prostate cancer in four brothers

We identified a family of 4 brothers with prostate cancer. The proband was the second son who was seen at the Department of Urology, Gunma University, Gunma, Japan, in May 1995, with a chief complaint of dysuria. The serum level of PSA was high, and a prostate needle biopsy revealed a moderately-differentiated adenocarcinoma. Subsequently, a total prostatectomy was performed. The family history revealed that the fourth son had been under treatment at the Saitama Cancer Center Hospital for prostate cancer since 1994. Therefore, the other 2 brothers became healthy male family members of the familial prostate cancer line, and their serum PSA levels were examined after obtaining their informed consent. Both had a high serum PSA level and biopsies revealed moderately-differentiated adenocarcinomas in both. Human leukocyte antigen class II gene typing was conducted on 3 of 4 brothers and 4 healthy family members who gave informed consent, and revealed the DRB1*0901-DQB1*0303 haplotype in the first, second and third sons. Familial prostate cancer is well documented in Europe and the US where the incidence of prostate cancer is high, but this is the first report of prostate cancer in 4 brothers in Japan.

Thrombospondin 2 gene expression is correlated with decreased vascularity in non-small cell lung cancer

Stromal vascularity is thought to be a major factor involved in the progression of carcinoma. However, the crucial mechanisms of vascularization in the stroma are not well understood. Vascularity could be regulated by various cytokines produced by neoplastic or stromal cells in carcinoma. Thrombospondin (TSP) has an inhibitory role against vascularization in vitro, although the biological significance of TSP has not been characterized in vivo. We examined expression of TSP1 and TSP2 genes in 78 non-small cell lung cancers (NSCLCs) and 33 extraneoplastic lung tissue samples by reverse transcription-PCR. TSP1 expression was detected in 66.7% (52 of 78) of NSCLCs and in 69.7% (23 of 33) of extraneoplastic lung tissue specimens. TSP2 expression was seen in 48.7% (38 of 78) of NSCLCs, whereas 72.7% (24 of 33) of extraneoplastic lung tissue samples showed TSP2 gene expression. TSP2 expression was significantly decreased in NSCLC as compared with extraneoplastic lung tissue (chi2 test, P=0.019). Vascularity in the NSCLC was inversely correlated with TSP2 gene expression (Mann-Whitney U test, P=0.009). Patients with adenocarcinoma positive for TSP2 gene expression (22 of 49) showed significantly better prognosis than those without TSP2 (27 of 49; Cox-Mantel test, P=0.034). TSP1 expression showed no apparent correlation with these factors. These results suggested that TSP2 had an inhibitory role against vascularization and progression of NSCLC.

Two-dimensional configuration of the myoneural junctions of human masticatory muscle detected with matrix electrode

Motor unit action potentials (MUAPs) propagate bidirectionally from the myoneural junction along the muscle fibre. The propagation of excitation within single motor units can be detected during sustained isometric contraction using a surface electrode array. Electromyographic (EMG) signals from an adjacent pair of contacts along the muscle fibres show a very similar wave form with a time shift. In the present study, EMG signals of the masseter and the temporal muscles were obtained from two male adults during clenching in the intercuspal position using the multichannel surface electrode with 17 x 11 contacts. The two-dimensional location of the myoneural junction for each column from the source of the propagation was estimated. Each of the myoneural junctions was located in the lower portion of the masseter muscle and in the upper portion of the temporal muscle. However, the junction was distributed within 10 mm along the muscle fibres at different contraction levels in each muscle. This noninvasive technique of multiple surface electrodes enabled us to add to knowledge of the anatomical structure of the masticatory muscles examined.

Inhibition of tumor growth by ribozyme-mediated suppression of aberrant epidermal growth factor receptor gene expression

BACKGROUND

Amplification and rearrangement of the epidermal growth factor receptor (EGFR) gene is frequently associated with malignant gliomas. One type of EGFR mutation in primary gliomas results in overexpression of an aberrant EGFR messenger RNA (mRNA) that lacks sequences of exons II through VI of the human EGFR gene. We observed that the aberrantly spliced EGFR mRNA contains a ribozyme cleavable sequence (5'-AAG GUA AUU-3') created by the joining of EGFR exon I to exon VII. We hypothesized that an appropriately designed ribozyme RNA could mediate site-specific cleavage of the aberrant EGFR mRNA and reduce the growth of aberrant EGFR-producing tumor cells.

METHODS

We synthesized aberrant EGFR mRNA substrates and a sequence-specific hammerhead ribozyme (abEGFR-rib) to examine the ribozyme's activity in vitro. We also constructed an abEGFR-rib plasmid and introduced it into ERM5-1 cells, which are murine NIH3T3 cells transfected to express an aberrant EGFR complementary DNA. We measured the growth potential of the cotransfected cells in culture and in nude mice.

RESULTS

The synthesized abEGFR-rib efficiently and specifically cleaved aberrant EGFR mRNA substrates in vitro. Expression of the transfected abEGFR-rib suppressed expression of aberrant EGFR mRNA in ERM5-1 cells and reduced the growth of tumors formed by the cotransfected cells in nude mice. Finally, the incorporation of bromodeoxyuridine, a measure of mitotic activity, was also decreased in abEGFR-rib-producing ERM5-1 cells in vivo.

CONCLUSION

Ribozymes targeted to aberrant EGFR mRNA can inhibit the growth of tumors formed by cells that express this mRNA.

Quantitative evaluation of irregular astigmatism by fourier series harmonic analysis of videokeratography data

PURPOSE

To assess quantitatively corneal irregular astigmatism in association with best spectacle-corrected visual acuity.

METHODS

Refractive powers on a mire ring measured with computerized videokeratography were decomposed, using the Fourier series harmonic analysis. Extracting spherical and regular astigmatic components, the remaining irregular astigmatic component was quantified on rings 2 through 9. A weighted average was calculated by using the Stiles-Crawford effect on the basis of the radius of each ring of each eye and was used as an index of the irregular astigmatic component. Data analyses were carried out in 108 eyes, including 53 normal eyes, 34 eyes with keratoconus, and 21 eyes that had undergone penetrating keratoplasty for keratoconus. Keratoconic eyes and eyes after keratoplasty were included in the study only if visual acuity, corrected with a hard contact lens, was 20/20 or better. Logarithm of best spectacle-corrected visual acuity, age, type of disease, refractive astigmatism, irregular astigmatic component, surface regularity index, and surface asymmetry index were analyzed.

RESULTS

In results of multiple regression analysis, the irregular astigmatic component was significantly correlated with best spectacle-corrected visual acuity (r = -0.744; adjusted R2 = 0.549; P < 0.001), whereas other explanatory variables showed no correlation with best spectacle-corrected visual acuity.

CONCLUSIONS

This model of the irregular astigmatic component seems to be an efficient, quantitative means of describing corneal irregular astigmatism.

A human lung cancer xenograft producing granulocyte-colony stimulating factor and parathyroid hormone-related protein

A human lung cancer xenograft, LC-GP, producing granulocyte-colony stimulating factor and parathyroid hormone-related protein was established by transplantation into severe combined immunodeficient (SCID) mice. The lung cancer patient and SCID mice bearing LC-GP showed leukocytosis and hypercalcemia. G-CSF and PTHrP gene expression were demonstrated in the primary lung cancer, metastatic lesions and LC-GP xenograft. Immunohistochemical analysis confirmed the presence of G-CSF protein in LC-GP xenograft cells. LC-GP possessed activated c-Ki-ras oncogene (point mutation at codon 12). This LC-GP lacked apparent G-CSF receptor expression. The expression of G-CSF and PTHrP may be coregulated by the activated c-Ki-ras oncogene, and autocrine stimulation of G-CSF is unlikely.

Expression of cell-associated isoform of vascular endothelial growth factor 189 and its prognostic relevance in non-small cell lung cancer

Vascular endothelial growth factor (VEGF) has four isoforms (VEGF121, VEGF165, VEGF189, VEGF206). We examined the expression patterns of VEGF isoforms in non-small cell lung cancer (NSCLC) by RT-PCR. The cell-associated isoform VEGF189 was more frequently expressed in NSCLC (90.5%) than in extraneoplastic lung tissue (57.6%, p=0.00004). Immunohistochemical examination confirmed VEGF protein expression in 33 of 76 NSCLC expressing VEGF189 (V189p+ group). The V189p+ group showed significantly poorer prognosis than those without VEGF189 mRNA and protein (V189p- group, p=0.01722). These results suggest that expression of the cell-associated isoform VEGF189 is closely associated with progression of NSCLC.

Vascular endothelial growth factor (VEGF) mRNA isoform expression pattern is correlated with liver metastasis and poor prognosis in colon cancer

Vascular endothelial growth factor (VEGF) is a well known factor that induces angiogenesis. Four isoforms, i.e. VEGF206, 189, 165, and 121, have been identified. We examined the isoform patterns of VEGF mRNA using reverse transcription polymerase chain reaction (RT-PCR) analysis in 61 colon cancers. All the colon cancers examined expressed VEGF121. The isoform patterns were classified into three groups: type 1, VEGF121; type 2, VEGF121 + VEGF165; type 3, VEGF121 + VEGF165 + VEGF189. Three of the 61 colon cancers examined showed type 1 expression, 26 showed type 2 expression and 32 showed the type 3 pattern. The patients with liver metastases showed the type 3 isoform expression pattern at a significantly higher incidence (12 of 16, 75%) than those without liver metastasis (20 of 45, 44%) (P=0.036). The type 3 isoform pattern was significantly associated with M1 stage (P=0.019). The patients with colon cancer and the type 3 isoform pattern showed significantly poor prognosis (P < 0.01, Cox-Mantel). The colon cancers with the type 3 pattern showed a significantly higher involvement of veins (P=0.006). These observations suggest that the aberrant type 3 expression pattern of VEGF189 mRNA isoforms is correlated with liver metastasis, M stage, and poor prognosis in colon cancer.

Baicalin, an inhibitor of HIV-1 production in vitro

The flavonoid baicalin markedly inhibits replication of human immunodeficiency virus type 1 (HIV-1) in a concentration-dependent manner in normal peripheral blood mononuclear cells (PBMC) stimulated with phytohemagglutinin (PHA) in vitro. The effect was more pronounced when the cells were pretreated with baicalin. Furthermore, baicalin inhibits HIV-1 replication in PHA-stimulated PBMC from asymptomatic HIV-1-seropositive carriers. The 50% inhibitory concentration for HIV-1 replication was approximately 0.5 microg/ml. At the concentration of 2 microg/ml of baicalin, copy numbers of HIV-1 proviral DNA were approximately 50 times less than in untreated controls. In a cell-free infection system, baicalin inhibited the activity of HIV-1 reverse transcriptase (RT), but not the activity of human DNA polymerases alpha and gamma (DNA polymerase beta was slightly inhibited), suggesting that the anti-HIV-1 effect of baicalin may at least partly be due to inhibition of HIV-1 RT.

Multidrug resistance mediated by overexpression of P-glycoprotein in human osteosarcoma in vivo

We examined the expression levels of P-glycoprotein (P-Gp)/the human multidrug resistance gene (MDR1) and in vivo chemosensitivity in the 7 osteosarcoma xenografts. Three of seven (43%) osteosarcoma xenografts expressed MDR1 by reverse transcriptase-polymerase chain reaction (RT-PCR). The OSS-516R xenograft selected with vincristine (VCR) from the MDR1-negative xenograft OSS-516, which was sensitive to VCR and doxorubicin (DOX), acquired cross-resistance to DOX. In the OSS-516R, RT-PCR assay showed definite MDR1 expression and immunohistochemical analysis demonstrated P-Gp-positive tumor cells. These results suggest that P-Gp/MDR1 overexpression is related to multidrug resistance in human osteosarcoma in vivo.

High energy radiofrequency catheter ablation for common atrial flutter targeting the isthmus between the inferior vena cava and tricuspid valve annulus using a super long tip electrode

There have been controversies concerning the optimal target sites and approaches in radiofrequency catheter ablation of common atrial flutter. We attempted high energy radiofrequency catheter ablation targeting the isthmus between the inferior vena cava and tricuspid valve annulus (IVC-TV isthmus) with a super long (8 mm) tip electrode, and compared the efficacy of this anatomical approach with the electrophysiological approach targeting the posteroseptal right atrium posterior to the coronary sinus using a standard 4-mm tip electrode. Atrial flutter was successfully ablated in 12 of 12 patients (100%) without recurrence with the anatomical approach, while, in 7 of 9 patients (64%) with 2 recurrences with the electrophysiological approach. In comparison of ablation data between the anatomical and electrophysiological approaches, there were significant differences in the mean number of application pulses (anatomical vs electrophysiological: 2.3 +/- 0.8 vs 9.9 +/- 6.4, P < 0.01), applied wattage (39 +/- 12 W vs 24 +/- 6 W, P < 0.01), applied energy per application (1,986 +/- 426 J vs 659 +/- 323 J, P < 0.01), fluoroscopic time (26 +/- 11 min vs 74 +/- 30 minutes, P < 0.01), and procedure time (59 +/- 8 min vs 181 +/- 53 min, P < 0.01). In conclusion, the anatomical approach is superior to the electrophysiological one with respect to procedure and radiation time, and linear ablation at the IVC-TV isthmus with an 8-mm tip electrode and high energy application is highly effective and safe.

[Current treatment burn wounds: alternative wound coverage methods]

In patients with massive burn injuries and very limited skin donor sites, both acute-phase and long-term problems of skin loss must be solved by the use of alternative wound closure materials. Alternative materials can be used for either temporary wound coverage or for permanent wound closure. Recently, allogenic skin grafts have most commonly been used as alternative wound closure material. However, research is ongoing on many new materials to provide a readily available substitute for skin allografts for permanent wound closure. The best approach to the development of alternative permanent wound closure materials is to incorporate the host's own cellular and structural components. Four general strategies have been devised so far based on the type of matrix structure and cellular content: allografts; cultured epidermal grafts; dermal matrix grafts; and cultured-dermal matrix composite grafts. Several approaches using combined alternative wound closure materials have been used, including transplantation of artificial dermal matrix with thin epidermal autografts, and transplantation of artificial dermal matrix containing human fibroblasts. Ultimately, the best candidate materials for permanent wound closure after extensive burn injury must be determined in prospective, randomized, controlled clinical trials.

[Properties of extracellular products produced by group A streptococci isolated from patients with streptococcal toxic shock syndrome]

Extracellular products of group A streptococci isolated from patients with streptococcal toxic shock syndrome (STSS) were examined. The outline of the discussion of the 3 products are as follows; streptolysin O (SLO), proteinase and erythrogenic toxin. SLO and proteinase showed a relatively large amount of products more than erythrogenic toxin. SLO produced by group A streptococci isolated from the patient with STSS had an isoelectric point (pI) of 6.0 and a molecular weight of 64,000 and showed hemolytic activity in the presence of 2-mercaptoethanol (2-ME). Furthermore, the hemolytic activities of all components were inhibited by gamma-globulin and cholesterol. Proteinase had pIs of 8.7 and 8.9, and a molecular weight of 21,000. These data suggest that STSS clinical criteria probably reflects a characteristic of a large amount of products of individual S. pyogenes isolates.

[A present situation of Foods for Specified Health Use (FOSHU) in Japan]

Seventy-nine products have been licensed as Foods for Specified Health Use (FOSHU) until 1997 by Ministry of Health and Welfare in Japan. Fifty-two of them are claiming Bifidogenicity and maintaining a good GI condition those which contain indigestible oligosaccharides or Bifidobacterium/Lactobacillus or dietary fiber. New type of FOSHU, concerning suppression of cholesterol absorption, mineral absorption, lowering blood pressure are increased recently.

Nonsurgical management of patients with blunt hepatic injury: efficacy of transcatheter arterial embolization

OBJECTIVE

We evaluated the efficacy of transcatheter arterial embolization (TAE) for patients with blunt hepatic injury.

SUBJECTS AND METHODS

Of 372 patients with trauma, 60 had evidence on CT of hepatic injury (Mirvis classification). Six of the 60 patients required emergency laparotomy and were excluded. Of the 54 remaining patients, 28 were classified as having high-grade hepatic injury (Mirvis classification of 3 or 4). All 28 underwent arteriography, and TAE was performed in single or multiple hepatic arterial branches when extravasation was seen. Angiography was repeated and cholescintigraphy was performed on patients with continued bleeding or biloma.

RESULTS

Injuries detected were grade 1 (n = 13), grade 2 (n = 13), grade 3 (n = 20), and grade 4 (n = 8). The injury was correlated with the degree of hemoperitoneum seen on CT. Patients with low-grade injuries (Mirvis classification of 1 or 2) were treated conservatively, and no deaths or liver-related morbidity occurred. Of the 28 patients with high-grade injury, 15 also had angiographic evidence of extravasation and underwent TAE. The average fluid resuscitation volume was significantly larger in this group than in the other 13 patients with high-grade injuries who did not undergo TAE. Embolization was successful in all 15 patients, and the shock index was significantly reduced after TAE. All patients survived, with follow-up at 1-8 months (2.5 +/- 1.8 months, mean +/- SD).

CONCLUSION

TAE is an effective alternative to surgery for patients with high-grade liver injury.

Inhibition of cholesterol biosynthesis by squalene epoxidase inhibitor avoids apoptotic cell death in L6 myoblasts

The relationship between the inhibition of cholesterol biosynthesis and occurrence of myopathy was studied in L6 myoblasts using two lines of cholesterol biosynthesis inhibitors, 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitor (simvastatin) and squalene epoxidase inhibitors (TU-2078 and NB-598). All inhibitors completely inhibited the cholesterol synthesis in L6 myoblasts at doses of 1 and 3 microM. Simvastatin (3 microM) inhibited the fusion reaction of L6 myoblasts followed by the severe cellular damage. The myoblasts also had failed actin fiber formation and creatinine phosphokinase (CPK) production. Additionally, this agent also caused apoptotic cell death in differentiated L6 muscle fiber, indicating that skeletal myopathy by HMG-CoA reductase inhibitors seems to occur not only in differentiating immature myoblasts but also in matured skeletal myotubes. In contrast, TU-2078 and NB-598 had no effect on the fusion reaction of differentiating myoblasts or on the cellular viability of muscle fiber at 3 microM, enough to completely inhibit cholesterol biosynthesis. It is conceivable that the mevalonate depletion and subsequent failure of ras farnesylation induced by simvastatin might cause the defects in differentiation and maintenance of the muscle fiber. Squalene epoxidase inhibitors did not show this adverse effect presumably because of the enzyme inhibition downstream of farnesyl synthesis. The present findings suggest the safe use of squalene epoxidase inhibitors in lipid-lowering therapy.

Efferent targets of osseous CGRP-immunoreactive nerve fiber before and after bone destruction in adjuvant arthritic rat: an ultramorphological study on their terminal-target relations

We report the ultramorphological characterization of the terminal-target relation of sensory peptidergic nerve fibers in healthy and diseased osseous tissues. Bone tissue sections were immunoelectronmicroscopically investigated for calcitonin gene-related peptide (CGRP), a neuropeptide widely distributed in sensory peptidergic fibers. Ultramorphological relation of the osseous CGRP-immunoreactive (ir) nerve terminals and their target cells was comparatively analyzed using healthy, arthritic, and postarthritic bone specimens from control and adjuvant-induced arthritic rats. Terminal-like profiles of the osseous CGRP-ir axons were evidenced in direct contact with the metaphyseal osteoblasts and osteoclasts of the control animals. Terminal-like profiles were also noted in the vicinity of the periosteal lining cells. Nonterminal-like profiles did not make intimate spatial relation to the cells/structures surrounding the nerve. Osseous CGRP-ir terminals and axons, which are either uncovered or thinly ensheathed by the supportive tissues, were extensively degenerated in adjuvant-induced infiltration, whereas larger fibers were relatively resistant. Numerous CGRP-ir axons with distinctive features reinnervated the postarthritic, ossifying periosteum. CGRP-ir axons appeared to reinnervate the eroded surface of metaphyseal bone and cartilage as early as the recruited osteoblasts resume osteogenesis in the postarthritic metaphysis. The observed terminal-target relations in the healthy and diseased bone tissues give an ultramorphological basis for the putative trophic, modulatory actions of CGRP innervation of the bone cells.

YM-32890 A and B, new types of macrolide antibiotics produced by Cytophaga sp

Two new types of macrolide antibiotics, YM-32890 A and B, have been isolated from the fermentation broth of cytophaga sp. YL-02905S. In this paper, the taxonomy of the producing strain, fermentation, isolation, structure elucidation, and biological activity of the antibiotics are reported. YM-32890 A inhibits the growth of staphylococci including a macrolide-resistant strain, but shows no antimicrobial activity against other Gram-positive, Gram-negative bacteria and yeast.

Efficacy of trimethoprim in murine experimental infection with a thymidine kinase-deficient mutant of Escherichia coli

The antimicrobial activity of trimethoprim is antagonized by thymidine in in vitro susceptibility tests. The purpose of this investigation was to determine whether this antagonism also occurred during experimental infection in mice, which have high serum thymidine concentrations. We derived a mutant strain of Escherichia coli, TT-48, incapable of utilizing exogenous thymidine from parent strain E. coli KC-14 and then investigated the in vitro and in vivo antimicrobial activities of trimethoprim, sulfamethoxazole, cefdinir, and ofloxacin against these strains. E. coli TT-48 lacked the activity of thymidine kinase, which catalyzes the conversion of thymidine to thymidylate, but its growth curve remained close to that of the parent strain. The MICs of all of the antimicrobial agents tested, except cefdinir, for the mutant strain were slightly inferior to those for the parent strain. The bactericidal effect of trimethoprim against the parent strain was antagonized by thymidine at concentrations of more than 1 microg/ml, while that against the mutant strain was not affected by thymidine even at the highest concentration (10 microg/ml). The therapeutic efficacy of trimethoprim in experimental murine infections was significantly higher when the mutant rather than the parent strain was used, whereas the therapeutic efficacy of cefdinir or ofloxacin, whose antimicrobial action is independent of folic acid synthesis, was the same with both strains. Unexpectedly, sulfamethoxazole also had similar efficacy against both strains. Thus, high thymidine concentrations antagonized the antimicrobial activity of trimethoprim in vitro and in vivo.

A xenograft line of human teratocarcinoma established by serial transplantation in severe combined immunodeficient (SCID) mice

We established a xenograft line of human teratocarcinoma (TC-1) and characterized the pluripotency of differentiation of the neoplastic cells. A teratocarcinoma specimen obtained from a primary mediastinal lesion (22-year-old male patient) was inoculated subcutaneously into severe combined immunodeficient (SCID) mice. The carcinoma formed tumors in the mice. We established a xenograft line by serial passage of the tumor in vivo. The primary tumor was composed of papillary and pseudoglandular nests of highly atypical epithelial cells with foci of glomeruloid structures. The metastatic cells showed apparent production of mucin and differentiation to striated muscle. The xenograft line TC-1 retained the basic histopathological features seen in the primary and metastatic cells. The xenograft line showed focal differentiation to cartilage through serial passages. Immunohistochemical studies with anti-alpha-fetoprotein (AFP) demonstrated positive immunoreactivity on the TC-1 cells. Serum AFP levels were also elevated in the TC-1-bearing SCID mice. The human teratocarcinoma xenograft line TC-1 will be useful for studying the differentiation mechanism in human totipotent stem cells.

Radiofrequency catheter ablation of posteroseptal atrioventricular accessory pathways--location-specific electrographic characteristics of successful ablation sites

The electrographic features of successful sites of radiofrequency catheter ablation were analyzed in 33 cases of posteroseptal accessory pathways and compared with those from 155 cases of free wall accessory pathways. The atrioventricular intervals in the posteroseptal cases were significantly longer than in the free wall cases (posteroseptal vs left and right free wall; 38 vs 33 and 26 msec, respectively; p < 0.05), and the incidences of continuous electrograms (42 vs 63 and 79%; p < 0.01) and PQS-pattern unipolar electrograms (50 vs 76 and 78%; p < 0.05) were significantly lower in the posteroseptal cases. The V-delta intervals in the posteroseptal cases were significantly longer than in the left free wall cases (17 vs 13 msec; p < 0.05), but shorter than in the right free wall cases (17 vs 23 msec; p < 0.05). No statistically significant difference in the incidence of Kent potentials among the 3 groups was observed. In radiofrequency ablation of posteroseptal pathways, the length of the atrioventricular interval and the incidences of continuous electrograms and PQS-pattern unipolar electrograms may be unsatisfactory even at the appropriate target site, but the V-delta interval and Kent potential are good indicators of suitable target sites.

P-glycoprotein-mediated acquired multidrug resistance of human lung cancer cells in vivo

We examined whether the increased expression of P-glycoprotein (P-gp) encoded by the human multidrug resistance gene MDR1 is related to the acquired multidrug resistance of lung cancer in vivo. We estimated the chemosensitivity of lung cancer xenografts (LC-6, adenocarcinoma; Lu-24, small-cell cancer) by calculation of relative tumour growth (T/C%, treated/control) in vivo, based on statistical significance determined by the Mann-Whitney U test (P < 0.01, one-sided). MDR1 gene expression levels were evaluated by reverse transcription-polymerase chain reaction (RT-PCR) assay. P-gp production and P-gp localisation were examined by Western blotting and by immunohistochemical analysis respectively. LC-6 and Lu-24 were initially sensitive to both vincristine (VCR, 1.6 mg kg-1: LC-6, 45%; Lu-24, 39%) and doxorubicin (DOX, 12 mg kg-1: LC-6, 26%; Lu-24, 27%) in vivo. VCR-resistant variants (LC-6R, 66% and Lu-24R, 68%) selected with VCR (0.4 mg kg-1, x 9) significantly acquired cross-resistance to DOX (LC-6R, 55% and Lu-24R, 55% respectively). RT-PCR assay showed increased levels of MDR1 expression in LC-6R and Lu-24R with stable MDR1 expression levels. P-gp expression levels were elevated, and the percentage of P-gp-positive tumour cells increased in both LC-6R and Lu-24R. These results suggest that P-gp/MDR1 overexpression is related to acquired multidrug resistance in lung cancer in vivo.

Treatment with 15-deoxyspergualin induces temporal suppression of hemopoiesis and changes thymocyte populations in mice

Effects of the immunosuppressive agent, 15-deoxyspergualin (DSG) on hemopoiesis and thymocyte populations were examined in mice. The numbers of bone marrow (BM) cells decreased after the administration of DSG for up to 8 days, and the extent of this decrease was correlated inversely to the time of administration. Conversely, the BM cells of DSG-treated mice had enhanced proliferative responses in vitro and in viv. Deoxymethylspergualin, DSG analogue, directly suppressed the proliferation of BM cells in vitro in a time and dose-dependent manner. Total thymocyte counts decreased following the administration of DSG. The numbers of immature, peanut agglutinin-binding (PNA+) thymocytes decreased notably. Minor changes were observed in the mature thymocytes and spleen cells of DSG-treated mice.

Hexamer palindromic oligonucleotides with 5'-CG-3' motif(s) induce production of interferon

We have shown previously that 30-mer oligonucleotides containing hexamer palindromic sequences with 5'-CG-3' motif(s) induce interferon (IFN), activate natural killer (NK) cells, and thus exhibit tumor-regressing activity. The present study showed that a hexamer palindromic oligonucleotide (5'-AACGTT-3') alone induced IFN from mouse spleen cells when added with cationic liposomes. Accordingly, 32 kinds of hexamer palindromic oligonucleotides were tested for their ability to induce IFN in the presence of cationic liposomes. The results show that oligonucleotides with NACGTN and NTCGAN sequences exhibited the strongest activity. ACGCGT and TCGCGA also possessed moderate but significant activity. In contrast, palindromes without CG motif(s) were devoid of the activity. No hexamer oligonucleotides showed the activity when liposomes were absent. A complete palindromic sequence was essential as any single base substitution resulted in diminished activity. Among variety of palindromic oligonucleotides of different sizes with an ACGT sequence at the center, the tetramer oligonucleotide was without activity, whereas the activity of hexamer and longer oligonucleotides was almost equally high. These results strongly suggest that the minimal essential structure required for IFN induction is the hexamer palindromic sequence with CG motif(s).

Novel 5-hydroxytryptamine (5-HT3) receptor antagonists. IV. Synthesis and pharmacological evaluation of the oxidation products of (-)-(R)-5-[(1-methyl-1H-indol-3-yl)carbonyl] -4,5,6,7-tetrahydro-1H-benzimidazole hydrochloride (YM060: ramosetron)

In physicochemical and pharmacokinetic evaluations of (--)-(R)-5-[(1-methyl-1H-indol-3-yl)carbonyl] -4,5,6,7-tetrahydro-1H-benzimidazole hydrochloride 1 (YM060: ramosetron), which is a highly potent 5-hydroxytryptamine(-HT3) receptor antagonist, 4-hydroxy-6-[(1-methyl-1H-indol-3-yl) carbonyl]4,5,6,7-tetrahydro-1H-benzimidazole 2 was identified as a degradation product and metabolite of 1. The (--)-(4R,6S)-isomer 2 was synthesized from the diketone derivative 3, via the stereoselective reduction of 3 followed by the stereocontrolled epimerization of the (--)-(4S,6S)-isomer 10, the epimer of 2. The stereochemistry of 2 and 10 was determined by NMR and HPLC studies. Compounds 2 and 10 were found to be potent 5-HT3 receptor antagonists, like 1. Among the other oxidation products, the diketone derivatives 3 and 7 and the dihydroxylated derivative 4 retained antagonistic activity similar to that of ondansetron. This is of interest, because they do not possess the amine group which is known to be necessary for high affinity to the 5-HT3 receptor.

Enzymes for anandamide biosynthesis and metabolism

Anandamide is an endogenous ligand for cannabinoid receptors. We tried to isolate and purify "anandamide amidohydrolase' which hydrolyzes anandamide to arachidonic acid and ethanolamine. The enzyme activity was found in the microsomal fraction of porcine brain homogenate. The enzyme was solubilized in 1% Triton X-100, and partially purified by hydrophobic chromatography to a specific activity of about 0.3 mumol/min per mg protein (37 degrees C). Apparent K(m) for anandamide was about 60 microM. The enzyme reacted also with ethanolamides of linoleic, oleic, and palmitic acids at lower rates. This enzyme preparation also converted arachidonic acid to anandamide in the presence of 250 mM concentration of ethanolamine. Several lines of evidence including experiments using various inhibitors suggested that the anandamide synthase and amidohydrolase activities were derived from a single enzyme protein.

Novel 5-hydroxytryptamine (5-HT3) receptor antagonists. III. Pharmacological evaluations and molecular modeling studies of optically active 4,5,6,7-tetrahydro-1H-benzimidazole derivatives

The R- and S-enantiomers of the 4,5,6,7-tetrahydro-1H-benzimidazole derivatives 3-8 were prepared by optical resolution. Each R-isomer, except for 3, was almost two orders of magnitude more potent than its S-isomer as a 5-hydroxytrptamine (5-HT3) receptor antagonist, as judged from they effect on the von Bezold-Jarisch reflex (B. J. reflex) in rats, the contraction of isolated guinea-pig colon and the receptor-binding affinity. The (--)-(R)-5-[(1-methyl-1H-indol-3-yl)carbonyl] derivative 6R.HCl (ramosetron = YM060) and (--)-(R)-5-[(1-indolinyl)carbonyl] derivative 4R.HCl (YM114 = KAE-393) given p.o. were hundreds of times more potent than 1 (ondansetron) and 2 (granisetron) in their inhibitory effects on cisplatin-induced emesis in ferrets and restraint stress-induced increases in fecal pellet output in rats. Three-dimensional molecular modeling studies suggested that the 'chiral selection' of the enantiomers might be influenced by the steric repulsion between the aromatic ring part and the conformationally restricted 4,5,6,7-tetrahydro-1H-benzimidazole ring in "equatorial-twist" conformation. In our pharmacophore model for the 5-HT3 receptor antagonist, a basic center exists at the left side of the aromatic-carbonyl plane when viewing from the aromatic part with the carbonyl oxygen atom upwards, whereas the "handedness" is ambiguous in the previously proposed model.

YM-24074, a new peptide antibiotic. II. Structural elucidation

YM-24074 (formerly called YL-01869P) is a new antibiotic and type I collagenase inhibitor. The structure of this compound was elucidated by spectroscopic analysis and confirmed by acid degradation to be N-(1"-acetyl-3"-methylbutyl)-2- [2'-[(N-hydroxycarbamoyl)methyl]heptanoyl]-hexahydropyrid azine-3-carboxamide. The stereochemistry of two of three chiral centers was determined by degradation products to be 3S, 2'R.