Role of Ca2+ on endotoxin-sensitivity by galactosamine challenge: lipid peroxide formation and hepatotoxicity in zymosan-primed mice

This study was investigated to clarify the role of intracellular Ca2+ following endotoxin treatment (1 mg/kg, intraperitoneally) to D-galactosamine-sensitized mice (400 mg/kg, intraperitoneally), and to observe lipid peroxide levels, an index of hepatotoxicity, in endotoxin/galactosamine (Ga1N)-challenged mice under activation of macrophages, especially Kupffer cells, by zymosan. The liver lipid peroxide level and serum glutamic pyruvic transminase activity in mice 18 hr after administration of endotoxin/Ga1N were markedly higher than those in mice treated only with endotoxin. In spite of an increase in lipid peroxide formation, there was little or no effect of Ga1N administration on xanthine oxidase and superoxide dismutase activities in mice given endotoxin. However, the injection of verapamil (10 mg/kg, subcutaneously) markedly decreased lipid peroxide levels in liver of endotoxin/Ga1N-injected mice. In the mice given a Ca(2+)-deficient diet, lipid peroxide level in liver after endotoxin/Ga1N injection was markedly decreased compared to that in mice fed a normal diet. Administration of dexamethasone (200 micrograms/kg, intraperitoneally) in mice 1 hr before treatment with endotoxin/Ga1N did not induce lipid peroxide formation. Administration of endotoxin to Ga1N-treated mice resulted in a higher level of liver cytosolic free Ca2+ ([Ca2+]i) than that in endotoxin-treated mice. On the other hand, Ca(2+)-ATPase activity in liver plasma membrane in the endotoxin/Ga1N-treated mice was markedly decreased as compared with endotoxin alone. On the contrary, the Ca(2+)-ATPase activity in liver mitochondria was higher in endotoxaemic mice treated with GA1N than in mice given endotoxin alone.(ABSTRACT TRUNCATED AT 250 WORDS)

Activation mechanism of phospholipase D involved in the generation of lipid mediators in cultured Madin-Darby canine kidney cells

Addition of 100 nM phorbol 12-myristate 13-acetate (PMA), an active phorbol diester, to quiescent cultured Madin-Darby canine kidney (MDCK) cells caused a maximal stimulation of phosphatidylethanol formation within 1-2 h in the presence of 1% ethanol, indicating the activation of phospholipase D (PLD). The specificity of phorbol diesters for the activation of PLD activation was confirmed by the fact that phorbol 12,13-dibutyrate (PDBu) was effective, whereas 4 alpha-phorbol 12,13-didecanoate (4 alpha-PDD) was without effect. Down-regulation caused by the long-term pretreatment of the cells with active phorbol diesters significantly decreased the production of phosphatidylethanol. Staurosporine, a well known protein kinase (PK)C inhibitor at 1 microM, decreased the activation of PLD. Taken together, these observations suggested the involvement of PKC in the activation of PLD. The cellular PLD activity was found to be selectively localized in the particulate fraction by centrifugation at 12,000 x g. The particulate PLD showed the selective substrate specificity for phosphatidylcholine rather than phosphatidylethanolamine. In response to the addition of 100 nM PMA, 1,2-diacylglycerol (DG) increased in a biphasic fashion. In view of the time course of the activation of PLD, the second increase in the 1,2-DG around 20 min was contributed by the activation of PLD. In response to the simultaneous addition of 100 nM PMA and 100 nM A23187, the cultured MDCK cells activated the arachidonate cascades to form prostaglandin (PG)E2 and PGF2 alpha as major products, requiring slower 24 h to reach maximal levels.(ABSTRACT TRUNCATED AT 250 WORDS)

Association between elevated plasma granulocyte colony-stimulating factor and the degree of surgical stress in patients undergoing gastrointestinal surgery

To characterize the changes in perioperative plasma granulocyte colony-stimulating factor (G-CSF) and analyze the effect of surgical stress on its kinetics, 41 patients undergoing gastrointestinal surgery with varying degrees of surgical stress were examined. The plasma levels of G-CSF significantly increased immediately after the operation, probably in response to surgical injury. This elevation was much higher in the 15 esophagectomy patients, at 883 +/- 300 pg/ml on postoperative day (POD) O, than in the 14 gastrectomy patients, with a value of 233 +/- 151 on POD O, (P < 0.01) or in the 12 cholecystectomy patients, with a value of 64 +/- 41 on POD 1 (P < 0.01). These findings led us to conclude that G-CSF levels increase significantly in the immediate postoperative period and are most likely associated with the degree of surgical stress. In addition, we studied the priming effect of G-CSF on polymorphonuclear leukocytes (PMNs). G-CSF enhanced PMN superoxide anion (O2-) production and luminol-dependent chemiluminescence (CL) induced by opsonized zymosan in a dose-dependent manner. A significant enhancement was seen in the G-CSF level (1 ng/ml) which was almost the same as the maximum G-CSF level in the esophagectomy patients. Furthermore, postoperative PMN activation occurred after the elevation of plasma G-CSF. Thus, we propose that elevated G-CSF may act as one of the mediators which activate PMN function postoperatively.

Inhibitory effect of KBT-3022, a new anti-platelet agent, on infiltration of polymorphonuclear leukocytes induced by leukotriene B4 or formyl-methionyl-leucyl-phenylalanine in mice

We devised a method for evaluating polymorphonuclear leukocyte (PMN) infiltration in vivo employing an air bleb technique combined with measurement of myeloperoxidase (MPO) activity, and the effects of some anti-platelet agents were evaluated. KBT-3022 (ethyl 2-[4,5-bis(4-methoxyphenyl)thiazol-2-yl]pyrrol-1-ylacetate) and cilostazol inhibited the increase in MPO activity in the connective tissue around the air bleb induced by leukotriene B4 (LTB4) and formyl-methionyl-leucyl-phenylalanine (fMLP). Indomethacin inhibited only the fMLP-induced increase in MPO activity, but ticlopidine hydrochloride and acetylsalicylic acid had no effect. Histologic observation confirmed the inhibition of PMN infiltration by KBT-3022. These results indicate that KBT-3022 may be a potent inhibitor of both LTB4- and fMLP-induced infiltration of PMNs.

Anti-thrombotic activity of KBT-3022 in experimental models of thrombosis

In this study, we investigated the effects of KBT-3022 (ethyl 2-[4,5-bis(4-methoxyphenyl)-thiazol-2-yl]pyrrol-1-ylacetate) , a potent and long-lasting anti-platelet agent, in several experimental thrombosis models and compared them with those of other anti-platelet drugs. Oral administration of KBT-3022 prevented arachidonic acid-induced death due to pulmonary embolism in mice and rabbits with respective ED50 values of 0.29 and 0.12 mg/kg. The protective effect of acetylsalicylic acid (ASA) against mortality was weaker than that of KBT-3022, and ticlopidine hydrochloride (TP) showed no such effect in these models. In a guinea pig arterio-venous shunt model, the inhibition by KBT-3022 of thrombus formation on a silk thread inserted into the shunt was dose-dependent and 300 and 30 times more potent than the inhibition obtained with ASA and indomethacin, respectively. In a model of aortic thrombosis induced by perivascular application of 20% silver nitrate solution, KBT-3022 (1 mg/kg, p.o.) inhibited thrombus formation significantly, ASA (100 mg/kg, p.o.) tended to inhibit it, and TP had no effect. However, in a stasis-induced venous thrombosis model in guinea pigs, TP inhibited thrombus formation significantly, but KBT-3022 and ASA were ineffective. These results suggest that KBT-3022 may be a useful drug for the treatment and/or prophylaxis of thrombus formation in shunts and aortic thrombosis.

[Endoscopic treatment of esophageal and gastric cancers]

Since 1978 we have applied various endoscopic procedures to esophageal and gastric malignancies for a palliative or a radical purpose. An outline of our experience was presented herein. Endoscopic Laser irradiation has been given to 61 cases (64 lesions) of early gastric cancers as a radical treatment since 1978. The irradiation was repeated once a week until getting disappearance of cancer cells in biopsy specimens. The Laser irradiation has also been given to 13 cases of advanced gastric cancers since 1978 and 12 cases of advanced esophageal cancers since 1985 for palliative purposes, such as, mass reduction, hemostasis, and removals of stenosis or obstruction. From 1991 the endoscopic mucosal resection (EMR) method has been used to 75 cases (93 lesions) as a radical treatment for gastric adenomas (n = 24) and well-differentiated adenocarcinomas less than 2 cm in size without ulceration (n = 69). The endoscopic Laser irradiation for early gastric cancers showed a survival rate of 62.8% after 5 years. The recurrence was preferentially found in depressed cancers and polypoid cancers of more than 3 cm in size, and often appeared within one year after the treatment. The Laser treatment for advanced gastric and esophageal cancers showed a survival rate of 69% and 33% after 6 months, respectively. In many cases, subjective symptoms like gastric bleeding or dysphasia were markedly improved after the treatment. The complete removal of gastric tumors was obtained at 65% with the conventional strip biopsy method, and at 80% with the double snare polypectomy or EMR using the EVL device.(ABSTRACT TRUNCATED AT 250 WORDS)

cDNA cloning of a new putative ATPase subunit p45 of the human 26S proteasome, a homolog of yeast transcriptional factor Sug1p

The nucleotide sequence of a cDNA that encodes a new regulatory subunit, named p45, of the 26S proteasome of human hepatoblastoma HepG2 cells has been determined. The polypeptide predicted from the open reading frame consists of 406 amino acid residues with a calculated molecular weight of 45770 and isoelectric point of 8.35. The sequences of several fragments of bovine p45, determined by protein chemical analyses, spanning 27% of the complete structure, were found to be in excellent accord with those deduced from the human cDNA sequence. Computer analysis showed that p45 belongs to a family of putative ATPases which includes regulatory components of 26S proteasomes. The overall structure of p45 was found to be homologous to that of yeast Sug1p, which has been identified as a transcriptional factor. It is closely similar, but not identical to the sequence reported for Trip1, a functional homolog of Sug1p in human tissues. These results are consistent with the possibility that Sug1-like proteins with distinct sequence function in transcription and protein degradation in human cells. However, the alternative hypothesis, that the same gene locus encodes both p45 and Trip1, cannot be excluded on the basis of such closely similar sequences. In either case, both proteins are likely to function equivalently well in either transcription or protein degradation.

Depressive effect of a traditional Chinese medicine (sho-saiko-to) on endotoxin-induced nitric oxide formation in activated murine macrophage J774A.1 cells

The present study investigated whether or not Sho-saiko-to (crude powder extract, TJ-9) can suppress nitric oxide (NO) generation by endotoxin-activated J774A.1 cells in order to study the preventive mechanism of Sho-saiko-to against endotoxemia. In this experiment, we estimated the NO2- in the murine macrophage cell line J774A.1 using the Griess method. Our results clearly demonstrated that J774A.1 cells stimulated with endotoxin (0.01-10 micrograms/ml) can effectively produce NO, and the production was dependent on the dose of endotoxin. On the other hand, we investigated the suppressive effect of TJ-9 (10-100 micrograms/ml) on NO generation by endotoxin (0.1 microgram/ml)-activated J774A.1 cells. The NO level when the cells were incubated with endotoxin and TJ-9 (10-20 micrograms/ml) was slightly lower than that in cells treated with endotoxin alone. In contrast, treatment with TJ-9 (50-100 micrograms/ml) significantly inhibited endotoxin-activated NO generation in J774A.1 cells, whereas the treatment with TJ-9 (10-100 micrograms/ml) alone was ineffective in inducing NO formation and in inhibiting cell viability in the J774A.1 cells. These findings suggest that a Kampo presciption of Sho-saiko-to shows a suppressive effect on NO generation in macrophages stimulated with endotoxin, and that it may be useful in improving endotoxin-shock symptoms.

[Cell proliferation and cell death (apoptosis) as indices differentiating malignant from benign gastrointestinal myogenic tumors]

We examined whether the determination of cell proliferation and cell death rates was useful in the differential diagnosis between benign and malignant myogenic tumors of gastrointestinal tract. As markers for cell proliferation and cell death, Ki-67 (MIB-1) positive rates or argyrophilic nucleolar organizer region (AgNOR) counts and apoptotic cell counts were determined in a total of 53 myogenic tumors comprising 36 leiomyomas and 17 leiomyosarcomas. Apoptotic cells were detected with the in situ nick end labeling method reported by Gavrieli in 1992 with modifications. Significant differences were observed in the Ki-67 positive rates (leiomyoma 1.8 +/- 1.4%, leiomyosarcoma 8.6 +/- 6.0%, p < 0.0001), in the mean AgNOR counts (leiomyoma 1.77 +/- 0.53, leiomyosarcomas 3.14 +/- 1.02, p < 0.0001), and in the apoptotic cell counts (median; leiomyoma 3.2, leiomyosarcoma 32.5 per 10(6) tumor cells, p < 0.005). All high grade sarcomas were picked up by the Ki-67 index of more than 7%, and almost all leiomyomas were thrown away by the AgNOR counts more than 3.0 within the low Ki-67 cases, which showed 81% of sensitivity and 97% of specificity. These results show that a combination use of Ki-67 and AgNOR is of use in the differential diagnosis between leiomyoma and leiomyosarcoma. Although a significant difference was also noted in apoptotic cell counts between these two categories, this seems not to be a practical index for the discrimination because apoptotic cell death is a rare event in gastrointestinal myogenic tumors.

[Cell proliferation and cell death (apoptosis) in epithelial tumors of the stomach--analysis of tumor tissues by the endoscopic mucosal resection]

To answer the question why some gastric cancers make elevation while others make depression in their early stage, and why polypoid cancers grow larger than their benign counterpart adenomas, the distribution of proliferating cells and apoptotic cells was compared between these lesions. Proliferating cells and apoptotic cells were detected with anti Ki-67 antibody (MIB-1) and with the in situ nick end labeling (ISNEL), respectively. A total of 62 gastric tumors, taken by the endoscopic mucosal resection method, was assessed. They consisted of 14 adenomas and 48 mucosal carcinomas (27 polypoid and 21 depressed type). Overall positive rates of Ki-67 were 27.5 +/- 9.0% in adenoma, 40.1 +/- 11.1% in polypoid cancer and 47.5 +/- 9.7% in depressed cancer. Proliferating cells were preferentially found in the cripts of metaplastic mucosa, in the middle to upper layer of adenomas, and in the whole layer including their surface of adenocarcinomas. Within cancers the polypoid type had more positive cells in the upper layer, so did the depressed type in the lower layer. ISNEL positive nuclei showed sphere, fragmented, ringed forms, or the same form as neighboring tumor nuclei. Apoptotic cells lay scattered throughout tumor glands. Apoptotic cell counts per 1000 tumor cells were 26.0 +/- 9.7 in adenoma, 36.3 +/- 32.1 in polypoid cancer, and 52.5 +/- 19.3 in depressed cancer. Depressed type cancers and a few polypoid cancers rich in non-tumor tissues showed higher numbers of apoptotic cells than adenomas and usual polypoid cancers. (ABSTRACT TRUNCATED AT 250 WORDS)

Macromolecular ionophores. 1. Chiral recognition properties of poly[(1-->6)-2,5-anhydro-D-glucitol] toward racemic amino acid ester

The chiral recognition property of poly[(1-->6)-2,5-anhydro-3,4-di-O-alkyl-D-glucitol] (1) toward racemic RCH (CO2CH3)NH3+.PF6- (2.HPF6) has been studied using a transport system involving an aqueous source and receiving phases separated by a chloroform phase containing 1. Transport rates for aromatic guests 2a (R = Ph) and 2b (R = CH2Ph) were faster than those for aliphatic guests, 2c (R = CH(CH3)2) and 2d (R = CH2CH(CH3)2), using the polymer substituted with methyl groups (1a). The enantiomeric excess (e.e.) was 10.9% for 2a as a maximum value and decreased in the order of 2a > 2c > 2b = 2d. When the transport of 2a.HPF6 was carried out using the polymers with 3,4-di-O-methyl (1a), ethyl (1b), allyl (1c), and pentyl (1d) groups, the e.e. was 22.0% for 1d as a maximum value and increased in the order of 1a < 1b < 1c < 1d. The formation of a complex between 1a and 2a.HPF6 was confirmed by 1H and 13C NMR spectral measurements.

The effects of KBT-3022, a new anti-platelet agent, on hemorheological properties in guinea pigs

Using guinea pigs, a study was conducted on the effects of KBT-3022, a new anti-platelet agent, on hemorheological properties in various tests including blood filterability, blood viscosity, shear stress-induced red blood cell (RBC) deformability and contents of ATP and 2,3-diphosphoglycerate (2,3-DPG). Oral administration of KBT-3022 at 1 and 10 mg/kg significantly increased blood filterability, and significantly reduced blood viscosity at 10 mg/kg without changing the hematocrit, plasma fibrinogen concentration or plasma viscosity. KBT-3022 (10 mg/kg, p.o.) improved RBC deformability in response to shear stress, which was evoked by passing the blood through a thin tube. This dose of KBT-3022 also increased the contents of ATP and 2,3-DPG in RBC. These findings indicate that KBT-3022 may reduce blood viscosity as a sequel to improvement of RBC deformability through direct action on RBC. The increase in the intracellular levels of ATP and 2,3-DPG was considered to be involved in this improvement of hemorheological properties. These hemorheological effects of KBT-3022 appear to be promising for the treatment of patients with ischemic vascular disease.

[Exertional hypoxemia evaluated by pulse oximetry in patients with interstitial lung diseases]

The pattern of change in arterial oxyhemoglobin saturation (SpO2) measured by pulse oximetry (PO) during exercise, including daily activities, was studied in 23 patients with interstitial lung disease (ILD), 19 of whom had idiopathic pulmonary fibrosis, 3 collagen vascular disease, and 1 BOOP. Hypoxemia, as detected by PO appeared without dyspnea at the beginning of exertion or at a mild workload. Exercise usually induced significant changes in the same fashion first in heart rate, then in SpO2, and then in dyspnea, but stair climbing had a different pattern. Workload at the lactate threshold (LT) and symptom-limited maximal exercise (SL) in a bicyclergometer incremental exercise test correlated well with distance walked in a 10-minute walking test (10-eMD) (p < 0.01). Similarly, the degree in desaturation in each exercise test was closely correlated (p < 0.01). Exertional hypoxemia was more prominent in patients with ILD than in those with chronic pulmonary emphysema. Nevertheless, dyspne changed less per change in SpO2 in ILD patients. We conclude that prolonged monitoring of SpO2 by PO will disclose the presence of exertional desaturation in ILD patients.

[Macroscopic classification and kinetic alternations in the superficial lesion of colorectal neoplasms]

To clarify relation between macroscopic appearance and the mode of tumor growth in the superficial lesion of colorectal neoplasms, we compared their colonoscopic findings with histological architecture of tumor cells. Macroscopic type was classified into the superficial elevated lesion (II a, n = 42, mean 5.14mm) and the superficial depressed lesion (n = 42, mean 3.84mm). The latter was further divided into 3 subtypes; subtype A, an irregular depression with high marginal elevation (Dep (A), n = 20); subtype B, an irregular depression with irregular marginal elevation (Dep (B), n = 7); subtype C, a clear and wide depression without marginal elevation (Dep (C), n = 15). Histological architecture was evaluated by the transmucosal growth index (TGI) of tumor cells, which is a ratio of tumor width contacting with the muscularis mucosae against that of tumor surface, and by the distribution of proliferating cells detected by Ki-67 antibody (MIB-1). In adenomas TGI increased with a degree of central depression (IIa < Dep(A) < Dep(C)). In carcinomas TGI was high irrespective of their macroscopic forms. Ki-67 labeling indices tended to increase with histological atypia. Adenomas with severe atypia showed a high labeling consistent with carcinomas. In both adenomas and carcinomas, Ki-67 positive cells were mainly noted in upper third of neoplastic glands in II a, Dep (A) and Dep (B) neoplasms. By contrast, Dep (C) neoplasms lost a preferential distribution of proliferating cells, which reached the whole neoplastic glands. These results suggest that Dep (C) adenomas and carcinomas have a unique histopathological architecture in terms of a high TGI and an enlarged distribution of proliferating cells, implying a high malignant potential.

A novel mammalian Ras GTPase-activating protein which has phospholipid-binding and Btk homology regions

We have previously purified a novel GTPase-activating protein (GAP) for Ras which is immunologically distinct from the known Ras GAPs, p120GAP and neurofibromin (M. Maekawa, S. Nakamura, and S. Hattori, J. Biol. Chem. 268:22948-22952, 1993). On the basis of the partial amino acid sequence, we have obtained a cDNA which encodes the novel Ras GAP. The predicted protein consists of 847 amino acids whose calculated molecular mass, 96,369 Da, is close to the apparent molecular mass of the novel Ras GAP, 100 kDa. The amino acid sequence shows a high degree of similarity to the entire sequence of the Drosophila melanogaster Gap1 gene. When the catalytic domain of the novel GAP was compared with that of Drosophila Gap1, p120GAP, and neurofibromin, the highest degree of similarity was again observed with Gap1. Thus, we designated this gene Gap1m, a mammalian counterpart of the Drosophila Gap1 gene. Expression of Gap1m was relatively high in brain, placenta, and kidney tissues, and it was expressed at low levels in other tissues. A recombinant protein consisting of glutathione-S-transferase and the GAP-related domain of Gap1m stimulated GTPase of normal Ras but not that of Ras having valine at the 12th residue. Expression of the same region in Saccharomyces cerevisiae suppressed the ira2- phenotype. In addition to the GAP catalytic domain, Gap1m has two domains with sequence closely related to those of the phospholipid-binding domain of synaptotagmin and a region with similarity to the unique domain of Btk tyrosine kinase. These results clearly show that Gap1m is a novel Ras GAP molecule of mammalian cells.

[A randomized controlled trail of intensive and usual community-based education for blood pressure control]

A 1.5 year community-based hypertension education program was conducted and evaluated for the feasibility and effectiveness as a program for primary prevention of cardiovascular disease. The subjects were determined to be hypertensive from cardiovascular examinations and composed of 104 untreated men and women aged 35-69 whose blood pressure levels were between 140 and 179 mmHg for systolic and/or between 90 and 109 mmHg for diastolic and who had no evidence of hypertensive end organ effects in the 1990 examination. They were randomly assigned to either an intensive education (IE) group (n = 53) or a usual education (UE) group (n = 51) and invited to education classes six months later. The IE consisted of four education classes in the first six months and another 4 classes in the next 12 months. For the UE, one class in the first 6 months and another class in the next 12 months were held. Health education was focused on reduction of sodium intake, a 30 minutes of walking, and if necessary, reduction of alcohol and sugar intake. Mean (SD) values of systolic blood pressure at the start of the education program were 144.8 (11.7) mmHg in IE and 144.5 (12.2) mmHg in UE. The respective diastolic means (SD) were 80.6 (7.8) mmHg and 80.3 (8.6) mmHg. The proportion of persons who started to receive antihypertensive medication was 8-9% in both groups at six months, and 13% in IE and 29% in UE at 1.5 years. IE showed a 6 mmHg greater reduction in mean systolic blood pressure than UE at both six months and 1.5 years. No significant difference was found in diastolic blood pressure levels over time between the two groups. Dietary improvements related to reduction of salt intake were more evident in IE than in UE. There was no significant changes in means and distributions of relative weight index and alcohol intake in either group. Subgroup analysis according to antihypertensive medication use indicated that reduction of systolic blood pressure levels was significantly larger in IE than in UE for both no medication and medication subgroups at 6 months and 1.5 years. While it was difficult to evaluate an effect of the program at 1.5 years because of the difference in the proportion of medication use between IE and UE, the results at 6 months suggest that this community-based program was effective in reducing systolic blood pressure levels.

Cloning and nucleotide sequence of cDNA encoding Asp-hemolysin from Aspergillus fumigatus

The nucleotide sequence of a cDNA encoding Asp-hemolysin from Aspergillus fumigatus was clarified. The deduced amino acid sequence was shown to contain a set of negatively charged domains similar to portions of the cysteine-rich sequence in the ligand-binding domain of LDL-receptor. A potential signal sequence was also identified in the N-terminal domain of the deduced amino acid sequence.

cDNA cloning and interferon gamma down-regulation of proteasomal subunits X and Y

Proteasomes are the proteolytic complex responsible for major histocompatibility complex (MHC) class I-restricted antigen presentation. Interferon gamma treatment increases expression MHC-encoded LMP2 and LMP7 subunits of the proteasome and decreases expression of two proteasome subunits, named X and Y, which alters the proteolytic specificity of proteasomes. Molecular cloning of complementary DNAs encoding X and Y showed that their proteins are proteasomal subunits with high amino acid similarity to LMP7 and LMP2, respectively. Thus, interferon gamma may induce subunit replacements of X and Y by LMP7 and LMP2, respectively, producing proteasomes perhaps more appropriate for the immunological processing of endogenous antigens.

Neoadjuvant intra-arterial doxorubicin chemotherapy in combination with low dose radiotherapy for the treatment of locally advanced transitional cell carcinoma of the bladder

Between 1979 and 1990, 60 patients with locally advanced bladder cancer (stages T2 to 4NXM0) were treated with intra-arterial doxorubicin chemotherapy in combination with low dose radiotherapy and 36 (60%) achieved a complete remission. The tumor size (p < 0.01), tumor grade (p < 0.05) and clinical stage (p < 0.05) correlated significantly with the tumor response to the combined therapy. Of the 36 patients with complete remission and the 24 patients who did not achieve a complete remission 35 and 22, respectively, underwent a conservative bladder operation after treatment. Median followup was 71 months. The overall 5-year disease-free and cause-specific survival rates for the 60 patients were 49% and 72%, respectively. A significantly higher (p < 0.01) 5-year survival rate was observed in patients who achieved a complete remission (94%) than in those who did not (40%). The results suggest that intra-arterial chemotherapy plus radiotherapy is a useful regimen for patients with locally advanced bladder cancer, and bladder function may be preserved in those who achieve a complete remission.

[The effects of a novel Ca2+ channel blocker, KB-2796, on 5-HT-induced responses]

The effects of KB-2796, a new Ca(2+)-channel blocker, on 5-hydroxytryptamine (5-HT)-induced responses were investigated in comparison with those of other Ca(2+)-channel blockers such as verapamil, flunarizine, diltiazem and nimodipine. In rat cortical membrane, KB-2796 inhibited specific [3H]spiperone binding to 5-HT2 receptors in a competitive manner (Ki = 0.57 microM), but exhibited negligible affinity for radioligand binding to other 5-HT receptor subtypes such as 5-HT1, 5-HT1A, 5-HT1B, 5-HT1C and 5-HT3 at a concentration of 10 or 100 microM. KB-2796 inhibited both 5-HT-stimulated shape change and 5-HT and collagen-stimulated aggregation in rabbit platelet-rich plasma with IC50 values of 13.4 microM and 96.4 microM, respectively. KB-2796 also inhibited the 5-HT-induced increase of [Ca2+]i in washed rabbit platelets with the IC50 value of 25.7 microM. Furthermore, KB-2796 (3-30 mg/kg, p.o.) dose-dependently inhibited the 5-HT-induced paw edema in rats. In these experiments, the inhibitory effects of KB-2796 and other Ca2+ channel blockers were related to their affinities for the 5-HT2 receptor; and the potency of KB-2796 was stronger than those of diltiazem and nimodipine and almost equal to that of flunarizine, although all these inhibitors had weaker potencies than that of verapamil. These findings indicate that KB-2796 may possess antagonistic effect on the 5-HT2 receptor.