Preoperative endocrine therapy in patients with locally advanced prostate cancer

Recently, there has been increased interest in the application of preoperative endocrine therapy prior to radical prostatectomy for locally advanced cancer in order to enhance surgical curability and increase survival. Between 1986 and 1993, 40 patients with prostate cancer were given endocrine therapy before radical prostatectomy. Fifteen patients had stage B2 disease and 25 stage C. The median duration of preoperative endocrine therapy was 3.8 months, and all the patients subsequently underwent radical prostatectomy, pelvic lymphadenectomy and castration. There was an average 25.5% (0-71.8%) decreases in the maximal cross-sectional area of the prostate gland as determined by transrectal ultrasonography. Twenty-four of 25 patients with elevated levels of serum prostate-specific antigen (PSA) showed normal values after preoperative endocrine therapy. Evaluation of treatment-related histological effects, divided into three grades, revealed that 17 patients had pronounced, 11 moderate and 12 poor or no regression. Thirteen of the 40 patients (33%) demonstrated pathological downstaging of disease status from the diagnosis made at the initial clinical examination. After a median follow-up period of 36 months (3-100 months), 36 of the 40 patients are disease-free; two died of cancer 43 and 50 months after surgery, respectively. These results suggest that preoperative endocrine therapy may play an important role in the management of locally advanced prostatic cancer.

A novel 16,23-epoxy-5 beta-cholestane glycoside with potent inhibitory activity on proliferation of human peripheral blood lymphocytes from Ornithogalum saundersiae bulbs

A novel 16,23-epoxy-5 beta-cholestane triglycoside (1) was isolated from the bulbs of Ornithogalum saundersiae (Liliaceae). The structure was determined by extensive spectroscopic analysis. The conformation of the E-ring part of 1 was studied through molecular mechanics and molecular dynamics calculation methods. Compound 1 potently inhibited proliferation of peripheral blood lymphocytes provided from a chronic renal failure patient without causing any cytotoxicity in the lymphocytes and HL-60 human leukemia cells.

Steroidal saponins from the underground parts of Hosta longipes and their inhibitory activity on tumor promoter-induced phospholipid metabolism

Phytochemical study on the underground parts of Hosta longipes gave six new steroidal saponins together with a known one. The structures of the new compounds were determined by detailed analysis of their 1H- and 13C-NMR spectra including two-dimensional NMR spectroscopy, acid-catalyzed hydrolysis followed by chemical correlation, and by comparison with spectral data of known compounds. The isolated saponins and their aglycones were examined for inhibitory activity on 12-O-tetradecanoylphorbol-13-acetate (TPA)-stimulated 32P-incorporation into phospholipids of HeLa cells to identify new antitumor-promoter compounds.

Expression of manganese superoxide dismutase reduces tumor control radiation dose: gene-radiotherapy

This study investigated the in vitro and in vivo radiation response of tumor cells transfected with human manganese superoxide dismutase (MnSOD) cDNA. A major objective was to test the potential tumor suppressive effect of MnSOD in vivo. Tumor cells studied were an in vitro line derived from a murine spontaneous fibrosarcoma, FSa-II, which expressed an undetectable MnSOD activity. These cells were transfected with pSV2-NEO plasmid (NEO line) or cotransfected with MnSOD plasmid plus pSV2-NEO plasmid (SOD lines) as described previously. The cell lines used were SOD-L and SOD-H, which expressed, respectively, low and high MnSOD activities after transfection, and NEO and parental FSa-II controls. Both SOD-L and SOD-H cell lines were slightly more resistant to ionizing radiation than were the two control cell lines when irradiated in vitro in the presence of oxygen. The dose-modifying factors calculated at the survival level of 0.01 were 1.13 and 1.15 for the SOD-L and SOD-H cells, respectively. To investigate potential tumor suppressive effects, animal tumors of 4 mm diameter were irradiated in vivo under hypoxic conditions, and the radiation dose to control one-half of the irradiated tumors (TCD50) was determined for each tumor. The TCD50S obtained on the basis of the tumor control rate in 120 days after irradiation were substantially lower for the SOD-H and SOD-L tumors compared to the NEO tumors. They were 22.9, 28.6, and 47.5 Gy for SOD-H, SOD-L and NEO tumors, respectively. To analyze these data, survival curves were obtained for hypoxic cells by irradiating NEO and SOD-H tumors under hypoxic conditions in vivo and assaying in vitro. Analysis of these curves suggests that the decrease in the TCD50S of SOD tumors is attributable to the reduced tumorigenicity in these tumors. The hypoxic cell survival curves also showed that SOD did not protect cells from radiation in the absence of oxygen. Electron microscopy showed no morphological differences between these cells. These results suggest that the fraction of tumorigenic cells could be reduced by expression of MnSOD, resulting in a substantial decrease in the TCD50.

Inhibition of parathyroid hormone-related protein release by extracellular calcium in dispersed cells from human parathyroid hyperplasia secondary to chronic renal failure and adenoma

The relationship between parathyroid hormone-related protein (PTHrP) release from parathyroid cells and extracellular calcium ion concentration was investigated in three cases of parathyroid hyperplasia secondary to chronic renal failure and in four cases of parathyroid adenoma. Amounts of PTHrP released from individual parathyroid cells dispersed from surgical specimens were estimated by cell immunoblot assay. Parathyroid cells from both hyperplasias and adenomas showed significant suppression in the release of PTHrP with increase in extracellular calcium ions, but the amounts of PTHrP released from adenoma cells were significantly larger than from hyperplasia cells. The maximal value for PTHrP released within 120 minutes from adenoma cells was 2.91 +/- 2.11 x 10(-2) fmol/cell ([Ca2+], 0.4 mmol/L), and the minimal value was 1.32 +/- 0.35 x 10(-2) fmol/cell ([Ca2+], 2.0 mmol/L). On the other hand, the maximal value for PTHrP released from hyperplasia cells was 1.79 +/- 1.56 x 10(-2) fmol/cell ([Ca2+], 0.4 mmol/L), and the minimal value was 0.32 +/- 0.19 x 10(-2) fmol/cell ([Ca2+], 2.0 mmol/L). These results demonstrate actual release of PTHrP from abnormal parathyroid tissues into the extracellular space with the response to extracellular calcium ions depending on the cell status. Given the lack of definite histological criteria to differentiate between hyperplasias and adenomas in the parathyroid gland, the presently demonstrated significant difference in the ability to release PTHrP is important in pointing to parathyroid hyperplasia secondary to chronic renal failure as a distinct pathological entity separate from parathyroid adenoma.

Thalamocortical synapses between axons from the mediodorsal thalamic nucleus and pyramidal cells in the prelimbic cortex of the rat

A combined anterograde axonal degeneration and Golgi electron microscopic (Golgi-EM) study was undertaken to identify thalamocortical synaptic connections between axon terminals from the mediodorsal thalamic nucleus (MD) and pyramidal cells in layers III and V of the agranular prelimbic cortex in the rat. The morphological characteristics of thalamocortical synapses from MD were also examined by labeling axon terminals with anterograde transport of wheat germ agglutinin-horseradish peroxidase (WGA-HRP). WGA-HRP labeled axon terminals from MD to the prelimbic cortex were small in size (0.5-1 microns in diameter), contained round synaptic vesicles, and formed axospinous synapses with asymmetrical membrane thickenings. With Golgi-EM methods, gold-toned apical dendrites in layer III were analyzed by reconstruction of serial ultrathin sections. Following lesions in the thalamus, degenerating thalamocortical axon terminals formed asymmetrical contacts exclusively on dendritic spines of the identified apical dendrites. More thalamocortical synapses were found on apical dendrites of layer V pyramidal cells than on apical dendrites of layer III pyramidal cells. In addition to thalamocortical synapses, a very few unlabeled symmetrical synapses were found on apical dendrites and somata of pyramidal cells, but they were not quantified and their sources are unknown.

Primary biliary cirrhosis (PBC)-CREST (calcinosis, Raynaud's phenomenon, esophageal dysfunction, sclerodactyly and telangiectasia) overlap syndrome complicated by Sjögren's syndrome and arthritis

A 36-year-old woman with primary biliary cirrhosis (PBC)-CREST (calcinosis, Raynaud's phenomenon, esophageal dysfunction, sclerodactyly and telangiectasia) overlap syndrome complicated by Sjögren's syndrome and arthritis is reported. She had suffered from Raynaud's phenomenon, sclerodactyly, morning stiffness, arthralgia and sicca symptoms since 34 years of age. She exhibited an increased level of alkaline phosphatase and hyperglobulinemia at 2.8 g/dl without any symptoms, and histological findings from the biopsy specimen of the liver were consistent with those of PBC. Her human leukocyte antigen (HLA) typing was DR8 homozygous.

Hyalinizing trabecular adenoma of the thyroid: its unusual cytoplasmic immunopositivity for MIB1

The monoclonal antibody Ki-67 reacts with a human nuclear cell proliferation-associated antigen that is expressed in all active parts of the cell cycle and is well established as a marker of cell proliferation. However, the Ki-67 method requires fresh frozen material. Recently, MIB1 has been reported to give an immunohistochemical staining pattern identical to Ki-67 on paraffin-embedded tissue sections, frozen sections and cytological samples. This proliferation-associated antigen is apparently localized in the nucleus. Recently, we performed immunohistochemical staining using the monoclonal MIB1 antibody upon a variety of tumors and non-neoplastic conditions of the thyroid. Tumor cells of hyalinizing trabecular adenoma revealed an intense cytoplasmic immunopositivity for MIB1. In contrast, cytoplasmic immunostaining for MIB1 was negative in all other thyroid tumors and non-neoplastic lesions. Because of this unusual staining pattern, we repeated the staining of all cases and found the results to be reproducible. Therefore, we believe that positive cytoplasmic immunostaining for MIB1 is a characteristic finding of hyalinizing trabecular adenoma and is useful in differentiating it from other thyroid tumors.

Electron microscopic evidence that axon terminals from the mediodorsal thalamic nucleus make direct synaptic contacts with callosal cells in the prelimbic cortex of the rat

A combined study of anterograde axonal degeneration and HRP retrograde labeling has shown that there exist monosynaptic connections between afferent fibers from the mediodorsal thalamic nucleus (MD) and callosal cells in the prelimbic cortex of the rat. Degenerating axon terminals from MD made asymmetrical synaptic contacts with dendritic spines from apical dendrites of layer III pyramidal cells that were retrogradely labeled with HRP after its injection into the prelimbic cortex contralateral to MD lesions.

Antiviral effect of oryzacystatin, a proteinase inhibitor in rice, against herpes simplex virus type 1 in vitro and in vivo

Oryzacystatin (OC) is the first-described cystatin originating from rice seed; it consists of two molecular species, OC-I and OC-II, which have antiviral action against poliovirus in vitro (H. Kondo, S. Ijiri, K. Abe, H. Maeda, and S. Arai, FEBS Lett. 299:48-50, 1992). In the experiments reported here, we investigated the effects of OC-I and OC-II on the replication of herpes simplex virus type 1 (HSV-1) in vitro and in vivo. HSV-1 was inoculated onto monolayers of monkey kidney epithelial cells (CV-1 cells) at a multiplicity of infection of 0.1 PFU per cell. After adsorption of the virus onto cells, the cultures were incubated in the presence of either OC-I or OC-II in the concentration range of 1.0 to 300 microM, and the supernatant virus yield was quantitated at 24 h. The effective concentration for 90% inhibition of HSV-1 was 14.8 microM, while a cytotoxic effect on CV-1 cells without infection of HSV-1 was not observed below 500 microM OC-I. Therefore, the apparent in vitro chemotherapeutic index was estimated to be more than 33. In the mouse model of HSV-1-induced keratitis and encephalopathy, topical administration of OC-I to the mouse cornea produced a significant decrease in virus production in the cornea (mean virus yields: 3.11 log10 PFU in the treated group and 4.37 log10 PFU in the control group) and significant improvement in survival rates (P = 0.01). The in vivo antiherpetic effect of OC-I was comparable to that of acyclovir, indicating that topical treatment of HSV-1 infection in humans with OC-I might be possible. Our data also suggest the importance of some thiol proteinases, which may be derived from either the host's cells or HSV-1, during the replication process of HSV-1.

Two classes of cortical neurones labelled with Vicia villosa lectin in the guinea-pig

Cell surface substance(s) containing terminal N-acetylgalactosamine (GaINAc) was localized in the cerebral cortex of the guinea-pig. Vicia villosa and Glycine max, both specific to GaINAc, labelled the surface of the cell body of multipolar and triangular neurones. The labelling extended to the apical dendrite and axon initial segment in the triangular neurones. They were distributed exclusively in layer 5. Most of the labelled multipolar neurones contained a calcium-binding protein, parvalbumin (Pv), while none of the triangular neurones did. The findings indicate that, in the guinea-pig, pyramidal neurones as well as non-pyramidal interneurones are enwrapped by GaINAc-containing substances and suggest that this enwrapping does not seem to be linked to Pv production.

Inhibitory effects of steroidal saponins on 12-O-tetradecanoylphorbol-13-acetate (TPA)-enhanced 32P-incorporation into phospholipids of HeLa cells and proliferation of human malignant tumor cells

Certain Lilium plants contain (25S)-spirost-5-ene-3 beta,27-diol glycosides embracing 3-hydroxy-3-methylglutaric acid at the C-27 hydroxy position. One of their derivatives, methyl ester of (25R)-27-O-[(S)-3-hydroxy-3-methylglutaryl]-spirost-5-ene-3 beta,27-diol 3-O-(O-alpha-L-rhamnopyranosyl-(1-->2)-O-[beta-D-glucopyranosyl-(1-->4)] - beta-D-glucopyranoside) was found to inhibit 12-O-tetradecanoylphorbol-13-acetate (TPA)-stimulated 32P-incorporation into the phospholipids of human cervical cancer (HeLa) cells and also to inhibit the proliferation of various kinds of human malignant tumor cells, pancreatic cancer (PANC-1), osteosarcoma (OST), human gastric cancer (HGC-27), pheochromocytoma (PC-12) and HeLa cells, in vitro.

Tracheal tube cuff pressure during cardiac surgery using cardiopulmonary bypass

To determine the effects of cardiopulmonary bypass (CPB) on tracheal cuff pressure, we have measured intracuff pressure (ICP) in 29 consecutive patients undergoing cardiac surgery with CPB. Premedication comprised hyoscine and, after induction of anaesthesia with diazepam and fentanyl, followed by vecuronium, the trachea was intubated using a Portex Profile tracheal tube. Anaesthesia was maintained with high-dose fentanyl and 100% oxygen. ICP was measured with a transducer and the ICP was adjusted to 20 mm Hg. CPB was used with mild to deep hypothermia and blood-gas tensions were regulated according to alpha-stat (temperature uncorrected) pH management. Before CPB, ICP was significantly reduced from the mean baseline value of 20 (SEM 0.2) to 16.7 (0.6) mm Hg (P < 0.01). ICP changed significantly during CPB, decreasing to 8.0 (1.0) mm Hg before rewarming (P < 0.01 vs immediately before CPB) and increasing to 17.0 (0.6) mm Hg after the start of rewarming (P < 0.01 vs before rewarming). After CPB, ICP did not differ significantly from that immediately before CPB. We conclude that the decrease in ICP during the hypothermic phase of CPB may protect the tracheal mucosa against hypotensive ischaemic injury.

Isolation and the gene cloning of an alkaline shock protein in methicillin resistant Staphylococcus aureus

The growth of Staphylococcus aureus occurs at a wide range of pH(5-10), while the optimal is pH 7.0-7.5. The molecular mechanism of such pH tolerant properties should be elucidated because the production of the virulence factors was greatly affected by environmental pH. The effect of pH shift on the composition of cytosolic proteins in S. aureus was examined. A protein with a molecular mass of 23 kDa was remarkably enhanced by a pH upshift from 7 to 10. This alkaline shock protein (ASP23) was isolated and purified by ion-exchange chromatography. The N-terminal sequences of the purified protein and the protease-digested peptides were analyzed. The 320-bp DNA fragment that was designed from the peptide analysis was amplified. Using the amplified fragment as a probe, the ASP gene, asp23, was cloned. The deduced primary sequence of ASP23 comprised 169 amino acids with a calculated molecular weight of 19,191. Northern analysis revealed that asp23 was positively regulated at the transcription level by alkaline shock. Homology search revealed that asp23 is a novel gene. Although the physiological role of ASP23 has yet to be further analysed, we suggest that ASP23 plays a key role in alkaline pH tolerance of S. aureus.

Urine microscopy on a counting chamber for diagnosis of urinary infection

Several quantitative methods of urine microscopic examination for bacteriuria and pyuria on a blood cell counting-chamber have been found reliable for the diagnosis of urinary tract infection (UTI). However, no one technique has become popular or widely used because of laborious procedures associated with the method. We investigated the usefulness of microscopic examination of uncentrifuged urine on disposable counting-chambers. A total of 89 urine samples were obtained from 53 children (24 male and 29 female). Urine samples were examined for bacteriuria and pyuria using a disposable counting chamber and its reliability was analyzed in predicting significant bacteriuria defined by routine urine culture. Significant bacteriuria was diagnosed in 23 of 89 urine samples by urine culture. Microscopic urine examination on disposable counting-chambers was very easy without the need to set up or wash chambers and provided immediate information. Urine bacterial concentration determined by the counting-chamber method was closely correlated to that determined by bacterial culture. The counting-chamber method identified bacteriuria correctly in 21 of 23 urine samples diagnosed as significant bacteriuria (sensitivity = 91%) and also gave a correct diagnosis of 64 of 66 urine samples with non-significant bacteriuria (specificity = 98%). Nineteen of the 23 urine samples with significant bacteriuria also had pyuria. The positive predictive value of concomitant bacteriuria and pyuria was 100%. When neither bacteriuria nor pyuria was found, the negative predictive value was 100%. It was concluded that urine microscopy using disposable counting chambers was very easy, inexpensive, quick and reliable and thus an extremely useful method for diagnosing UTI.

Use of an SDS-gel-separated protein band as a ligand for affinity chromatography: procedure and application to the purification of domain-specific antibodies against alpha-actinin

This paper describes a simple and efficient method for preparing affinity columns. We used protein separated by sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis as a ligand. Protein bands detected in a polyacrylamide gel were electrophoretically transferred to CNBr-activated Sepharose using a buffer containing Nonidet P-40. The amount of ligand protein coupled to activated Sepharose by our method was almost comparable to that obtained by conventional coupling procedure with a native ligand protein. Using affinity columns prepared by this method, we have successfully purified anti-alpha-actinin antibody and antibodies highly specific to the rod domain of alpha-actinin from the antiserum. This new method should be useful for separating a specific antibody from an antiserum that has been raised against multiple antigens. In addition, the use of the SDS-gel-fractionated band facilitates the coupling of proteins that have low solubility under the coupling conditions.

Association of primary sclerosing cholangitis, thymoma and hypogammaglobulinemia

A 64-year-old Japanese woman with thymoma has been suffering from diarrhea and increased alkaline phosphatase levels without jaundice. Her serum immunoglobulin levels of IgM and IgG were less than half of the normal levels, with an increase in CD8 (suppressor/cytotoxic) T cell percentage and a decrease in CD4 (helper) T cell percentage, resulting in a lower CD4/CD8 ratio of 0.31. These immunological features are in accordance with those of hypogammaglobulinemia complicating thymoma. Cholangiography and a liver biopsy specimen disclosed the presence of primary sclerosing cholangitis (PSC). PSC has been recognized in various immunodeficiency syndromes and this case shows that thymoma complicated by hypogammaglobulinemia is associated with PSC.

The mechanism of lack of hypocholesterolemic effects of pravastatin sodium, a 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitor, in rats

In order to clarify the reason why pravastatin, a 3-hydroxy-3-methylglutaryl (HMG)-CoA reductase inhibitor, did not show hypocholesterolemic effects in rats, the changes of various parameters affecting the serum cholesterol levels by pravastatin were determined in rats and rabbits, as a comparison. In rabbits, pravastatin administration at 50 mg/kg for 14 days decreased serum and liver cholesterol by 40% and 8%, respectively. The hepatic LDL receptor activity was increased 1.7-fold, and VLDL cholesterol secretion was decreased. Cholesterol 7 alpha-hydroxylase activity was not changed. In contrast, in rats, serum cholesterol was increased by 14% at 50 mg/kg and 27% at 250 mg/kg for 7 days, respectively. At 250 mg/kg, liver cholesterol was significantly increased by 11%. Under these conditions, neither the hepatic LDL receptor activity nor cholesterol 7 alpha-hydroxylase was changed, and VLDL cholesterol secretion was increased. At 250 mg/kg, net cholesterol synthesis in rat liver was increased after 7 days of consecutive administration. These results imply that in rats, stimulated net cholesterol synthesis caused the increase of liver cholesterol followed by the increase of VLDL cholesterol secretion, and resulted in the raise of plasma cholesterol. Although hepatic HMG-CoA reductase was induced almost the same fold in both animals at 50 mg/kg, the induced HMG-CoA reductase activity in rats might overcome the inhibitory capability of pravastatin, resulting in an increase of net cholesterol synthesis, but not in rabbits. This over response to pravastatin in rats might cause the lack of hypocholesterolemic effects of this drug.

Effects of hyperthermia and cepharanthin on adriamycin accumulation with changes in extracellular pH

We compared adriamycin (ADR) accumulation with the intensity of intracellular fluorescence of 3,3'-(di-n-hexyl)-2,2'-oxacarbocyanine iodide (NK-2280), an indicator of cell membrane potential, after hyperthermia and examined the effects of cepharanthin (CEP) on the accumulation of ADR and NK-2280 in wild and ADR-resistant strains of Ehrlich ascites tumour (EAT) cells. Among wild 0.2 and 1-microgram ADR-resistant strains of EAT cells, intracellular accumulation of both ADR and NK-2280 decreased with an increase of ADR resistance. Hyperthermia at 42 degrees C and CEP induced a marked increase in accumulation of both ADR and NK-2280 in the ADR-resistant strains of EAT cells. The increase in ADR accumulation by hyperthermia and CEP is possibly due to an increase in the cell membrane potential and the inhibition of ADR efflux by CEP respectively. In the wild strain of EAT cells, we also evaluated the effect of extracellular pH change on ADR accumulation and the cell membrane potential and their alteration by hyperthermia and CEP. ADR accumulation decreased as pH decreased, but the cell membrane potential was not appreciably affected by pH change so far examined. Hyperthermia alone or combined with CEP significantly increased ADR accumulation in a pH range from 6.2 to 7.6. Hyperthermia increased the accumulation of ADR in the tumour cells, although its pH dependency was not completely resolved. CEP enhanced ADR accumulation more markedly in ADR-resistant cells than in wild-type cells. Therefore, the combination of hyperthermia and CEP may be very effective to increase the ADR cytotoxicity to ADR-resistant tumours.

Influence of the extracellular pH, an inhibitor of Na+/H+ exchanger and an inhibitor of Cl-/HCO3-exchanger on adriamycin accumulation

We examined the influence of the extracellular pH, an inhibitor of Na+/H+ exchanger: 3,5-diamino-6-chloro-N-(diaminomethylene) pyrazinecarboxamide (amiloride), and an inhibitor of Cl-/HCO3-: 4,4 -diisothiocyanatostilbene -2,2 -disulfonic acid (DIDS) on the accumulation of adriamycin (ADR) in Ehrlich ascites tumor cells and their adriamycin-resistant strain. A good correlation between the increases in ADR accumulation and the extracellular pH was shown in the both strains. The ADR accumulation decreased with an increasing concentration of amiloride or DIDS in both strains. These findings demonstrate that the influx of ADR was related closely to the efflux of H+ or to the activities of Na+/H+ ex-changer and Cl-/HCO3-exchanger. Therefore, raising the extracellular pH and enhancement of the activities of either Na+/H+ exchanger or Cl-/HCO3-exchanger may result in the potentiation of the cytotoxic effect of ADR through increase of ADR influx.

Ca2+ increase and pH decrease induced by hypochlorous acid in single quiescent myocytes isolated from rat ventricles

Cytosolic free calcium concentration ([Ca2+]i) and intracellular pH (pHi) were simultaneously measured with a fluorescence technique using fura-2 and BCECF. Hypochlorous acid (HOC1) increased [Ca2+]i and decreased pHi of single quiescent myocytes isolated from rat ventricles. The HOC1-induced changes in [Ca2+]i and pHi (delta [Ca2+]i and delta pHi) were 129 +/- 18nM and 0.18 +/- 0.02 (mean +/- SD), respectively, with 200 microM HOC1. A positive linear correlation was obtained between delta [Ca2+]i and delta pHi under various extracellular Ca2+, pH, and Na+ conditions. Chelation of extracellular Ca2+ depressed only one-fourth of delta [Ca2+]i, and Ca2+ antagonists (verapamil and nifedipine) did not reduce delta [Ca2+]i, indicating that delta [Ca2+]i originates mainly from intracellular Ca2+ stores. A disulfide-reducing reagent, 1,4-dithiothreitol (DTT), recovered the increased [Ca2+]i and decreased pHi to the control levels. The simultaneous changes in [Ca2+]i and pHi induced by HOC1 and the simultaneous restoration of the normal [Ca2+]i and pHi in cardiac myocytes.

Conformation of the C-terminus of endothelin-1 in aqueous solution studied by Monte-Carlo simulation

The conformation of the C-terminus of endothelin-1 in an aqueous solution has been analyzed by a Monte-Carlo simulation including the hydration energy term. The C-terminus may adopt multiple or flexible conformations in the solution, but the classification of the conformations shows that a comparably large number of conformers take a similar folding form in which the C-terminal chain is extended along the alpha-helix of the N-terminal core, and hydrophobic clusters are formed between the side groups of the C- and N-terminus. The aromatic ring of Trp21 is located at a certain distance from the two charged side groups of Asp8 and Glu10, and the functional groups of the key residues in the N-terminus are uncovered with the C-terminus tail.