20 alpha-hydroxysteroid dehydrogenase activity in canine spontaneous neoplasms

20 alpha-hydroxysteroid dehydrogenase (20 alpha-HSD) activities in 57 neoplastic tissues surgically removed from dogs were measured. Forty-eight of 57 tumor samples were shown to possess 20 alpha-HSD activity. These tissues were histopathologically classified into 22 benign and 26 malignant tumors. Among these tumors, mixed tumor types demonstrated the higher 20 alpha-HSD activity than epithelial and non-epithelial types, and malignant tumors of each tissue type showed slightly but not significantly higher 20 alpha-HSD activities comparing with the corresponding benign ones. Comparing with the activity of normal tissues examined, the corresponding tumor tissues showed significantly higher 20 alpha-HSD activities. Thus, 20 alpha-HSD activity was found in neoplastic tissues at a considerable high rate and the activity seemed to be higher in pathologically malignant tumors.

Age- and sex-related changes of sulfotransferase activities in the rat

Temporal and gender-related changes of sulfotransferase activities in the rat were studied using alcoholic, amine and phenolic compounds as substrates. Alcohol and amine sulfotransferase activities in the rat exhibited different temporal and sex-related changes of those for phenol. Formation of sulfoconjugates in vivo correlated well with in vitro sulfotransferase activities in the rat liver.

Structural study on the glycosyl-phosphatidylinositol anchor and the asparagine-linked sugar chain of a soluble form of CD59 in human urine

CD59 is an 18-kDa glycoprotein widely expressed on human cells. An important structural feature of CD59 is its attachment to the cell surface via a glycosyl-phosphatidylinositol (GPI) anchor. CD59, like many GPI-anchored proteins, has been found in urine, serum, and other body fluids. The structures of the GPI anchor and the asparagine-linked sugar chain of a soluble form of CD59 in urine, U-CD59, were determined. Purified U-CD59 released 1 mol of inositol per mole of protein by nitrous acid deamination, which cleaved between glucosamine and inositol present commonly in the GPI anchor. This indicates that a GPI anchor, which ended with inositol, is linked at the carboxy terminus of U-CD59. The peptide containing an asparagine-linked sugar chain and the peptide containing a glycan portion of the GPI anchor were isolated after trypsin digestion of U-CD59. The asparagine-linked sugar chains and the glycan portion of the GPI anchor were isolated from these peptides following hydrazinolysis or deamination and dephosphorylation, respectively. Their structures were analyzed by sequential exoglycosidase digestion and methylation analyses. The structures of the asparagine-linked sugar chains of U-CD59 were biantennary complex type, only 4.2% of which are monosialylated. The backbone structure of the GPI anchor was similar to that of Try-panosoma brucei variant surface glycoprotein, but showed significant variations in its side-chain moieties. This is the first detailed structural analysis of the human GPI anchor and the first detailed analysis of the carboxyl-terminal structure of the soluble-form GPI-anchored protein. The results indicate that the backbone structure of the GPI anchor is conserved from parasites to human and that at least a part of the soluble-form GPI-anchored protein has the structure produced by the action of glycan-phosphatidylinositol-specific phospholipase D.

Molecular cloning of cDNA for rat ovarian 20 alpha-hydroxysteroid dehydrogenase (HSD1)

20 alpha-Hydroxysteroid dehydrogenase (20 alpha-HSD, EC 1.1.1.149) catalyses the conversion of progesterone into 20 alpha-dihydroprogesterone (20 alpha-OHP). Previously, we purified the enzyme (37 kDa) from rat ovary and determined its N-terminal amino acid sequence. In the present study we succeeded in cloning a full-length 20 alpha-HSD cDNA. mRNA was extracted from immature rat ovaries after successive treatment with equine chorionic gonadotropin (eCG) and human chorionic gonadotropin (hCG). A cDNA library was constructed in lambda ZAP. For screening, a 576 bp probe was amplified by the PCR using mixed primers based on the N-terminal sequence of 20 alpha-HSD, and labelled with [32P]dCTP. Eight positive clones were isolated from 1.2 x 10(4) recombinants. Analysis of the nucleotide sequence revealed that one clone of 1.2 kbp cDNA (pHSD12-07) contained a polyadenylation site and an open reading frame encoding 323 amino acids with the N-terminal sequence of 20 alpha-HSD. The fusion protein of pHSD12-07 produced by Escherichia coli reacted with a specific polyclonal antibody generated against rat ovarian 20 alpha-HSD. In addition, the in vitro transcription-translation product produced by Xenopus oocytes showed 20 alpha-HSD activity and Northern-blotting analysis revealed that the ovaries from normal adult rats contained a 1.2 kb mRNA. Thus we succeeded in isolating a clone encoding the full length of rat ovarian 20 alpha-HSD. The sequence showed high similarity with those of rat liver 3 alpha-hydroxysteroid dehydrogenase (3 alpha-HSD), bovine lung prostaglandin F synthase (PGFS), human liver chlordecone reductase (CDR), frog lens rho-crystallin and aldose reductases, indicating that 20 alpha-HSD belongs to the aldo-keto reductase family.

Serum glucose and insulin levels and erythritol balance after oral administration of erythritol in healthy subjects

OBJECTIVES

To investigate the effect of an oral administration of erythritol on serum glucose and insulin levels in healthy subjects and estimate available energy of erythritol in human.

DESIGN

Ingestion of erythritol (0.3 g/kg body weight) or the same dose of glucose as a control.

SETTING

Omiya Research Lab., Nikken Chemicals Co., Japan.

SUBJECTS

5 healthy male volunteers aged 45-58 years.

MAIN OUTCOME MEASURES

Serum glucose, insulin and erythritol levels after erythritol ingestion. Urinary erythritol excretion.

RESULTS

Erythritol did not increase serum levels of glucose or insulin, while the same dose of glucose increased rapidly glucose and insulin levels within 30 min. Erythritol did not induce any significant effects on serum levels of total cholesterol, triacylglycerol, free fatty acids, Na, K and Cl. Also, urinary Na, K and Cl were not affected by erythritol ingestion. Serum levels of erythritol reached the maximum concentration of 426.5 +/- 113.4 micrograms/ml at 30 min and declined to 13.5 +/- 3.2 micrograms/ml at 24 h. Total urinary excretion of erythritol was 85.8 +/- 4.6% for 24 h and 90.3 +/- 4.5% for 48 h, respectively.

CONCLUSIONS

Erythritol did not affect serum levels of glucose, insulin or other serum constituents. More than 90% of ingested erythritol was readily absorbed and excreted in urine without degradation. This fact suggests that available energy of erythritol in human is less than 1.7 kJ/g (0.4 kcal/g).

DESCRIPTORS

erythritol, glucose, insulin, low energy sweetener.

Effects of the anabolic steroid nandrolone phenylpropionate on craniofacial growth in rats

Primary testosterone and its derivatives are anabolic steroids used in the treatment of osteoporosis and Turner syndrome. They also enhance fast-twitch muscle weight in female rats. The present study examines the effect of an anabolic steroid on craniofacial growth and development in rats. Five-week-old female Sprague-Dawley rats (125) were divided into experimental and control groups. The experimental group was injected subcutaneously with 1 mg nandrolone phenylpropionate in the interscapular region on alternate days, whereas those in the control group were injected with a vehicle, arachis oil. Rats were sacrificed at 60 and 120 days of age. Cephalometric analysis of soft X-ray cephalograms showed that chronic administration of the anabolic steroid, nandrolone phenylpropionate, resulted in: (1) about a 20% increase in body weight, (2) an increase in total skull length, (3) elongation of the maxillary and mandibular incisors, (4) an increase in the depth of the antegonial notch, and (5) downward-forward growth of the viscerocranium against the neurocranium. These results suggest that nandrolone phenylpropionate may accelerate craniofacial growth and/or induce high functional activity of the masticatory muscles in female rats.

The high affinity state of the beta 2-adrenergic receptor requires unique interaction between conserved and non-conserved extracellular loop cysteines

A disulfide bond between two extracellular cysteines, conserved in all G-protein-coupled receptors, is believed to be critical for stabilization of the ligand-binding pocket. The beta 2-adrenergic receptor (beta 2-AR) contains two conserved cysteines (Cys106 and Cys184) as well as two other extracellular cysteines (Cys190 and Cys191). The specificity of the interactions between these four cysteines has not yet been clearly established. Mutants encoding alanines for specific extracellular cysteines in the beta 2-AR gene were constructed and expressed in COS-1 and Chinese hamster ovary cells. Ala106, Ala184,190,191, and Ala106,184,190,191 mutants displayed low affinity for the beta-antagonist, 125I-cyanopindolol and insensitivity to dithiothreitol (DTT). The Ala106,191 mutant displayed an intermediate affinity and DTT sensitivity. Mutants Ala184, Ala184,190, and Ala184,191 displayed high affinity and DTT sensitivity, indicating that a solvent-accessible disulfide bond(s) is present in these mutant receptors as in the wild-type beta 2-AR. Additionally, thermal stability studies provided evidence that the extracellular disulfide bonds are essential for stabilization of the high affinity state of the receptor. These studies indicate that the covalent linkage between loops 1 and 2 of the beta 2-AR extracellular domains involves the formation of disulfide bonds, uniquely between Cys106 and Cys191, and Cys184 and Cys190, and is, thus, distinct from that of other G-protein-coupled receptors.

Role of endotoxin in L-arginine-induced relaxation of rat thoracic aorta mediated by muscle-derived nitric oxide

The contribution of endotoxin to the L-arginine-induced relaxation of the endothelium-denuded rat thoracic aorta, which appears to be mediated by nitric oxide synthase in the vascular smooth muscle, was investigated. Special attention was paid to the time course of the phenomenon and its dependence on the concentration of endotoxin. In the absence of endotoxin, L-arginine induced scarcely any relaxation of the arteries. Treatment of the arteries with endotoxin initiated relaxation in response to 10 microM L-arginine with lag periods of 2-4 hours. The degree of relaxation increased on repeated applications of L-arginine, to reach a consistent level after several hours. Increase in the concentration of endotoxin shortened the lag period, enhanced the degree of relaxation and lowered the threshold concentration of L-arginine required to relax the arteries. In endotoxin-primed arteries, L-arginine, at concentrations necessary to induce relaxation, stimulated the cyclic GMP production. Prophylactic application of actinomycin D or dexamethasone, which inhibits the induction of nitric oxide synthase, prevented the induction by endotoxin of the L-arginine-induced relaxation and cyclic GMP formation. Polymyxin B, which inhibits the action of endotoxin, also prevented the development of the endotoxin-sensitized relaxation and the cyclic GMP formation induced by L-arginine. When the Krebs solution was prepared using deionized water, the amount of endotoxin in the reservoir was above the level required to initiate the L-arginine-induced relaxation and cyclic GMP formation. These results suggest that endotoxin triggered the time-dependent development of the L-arginine-induced relaxation by expressing nitric oxide synthase in the vascular smooth muscle.

Effect of repeated injection of somatomedin C on drug metabolizing enzyme activities in rats

The effect of somatomedin C on the hepatic drug-metabolizing enzyme system in rat liver after sc injection, a clinically applicable dosing route, was studied. Although liver weight was slightly increased after somatomedin C (1 mg/kg) was injected for 7 days, no significant changes were observed in other dosing group (0.1 and 10 mg/kg). There were no significant effects of somatomedin C on cytochrome P-450 and b5 contents, and NADPH-cytochrome c reductase, aminopyrine demethylase, aniline hydroxylase, and ethoxyresorufin deethylase. Additionally, somatomedin C treatment did not affect the activities of 2 alpha-, 2 beta-, 6 beta- and 16 alpha-hydroxytestosterone and androstenedione formation from testosterone. Changes relation to dosing period were also examined with 1 mg/kg of somatomedin C. In this case, hepatic levels of cytochrome P-450 and b5, NADPH-cytochrome c reductase and drug oxidations did not differ significantly among groups treated for 3, 7, or 14 days. These results suggest that somatomedin C has no effect on the hepatic mixed-function oxidase system.

Amino acid sequences of Kunitz family subtilisin inhibitors from seeds of Canavalia lineata

The amino acid sequences of two subtilisin inhibitors (CLSI-II and -III) from Canavalia lineata seeds were determined by manual Edman degradation using the DABITC/PITC double coupling method after enzymatic digestions and CNBr degradation. CLSI-II and -III consist of 190 and 183 amino acids, respectively, and have identical amino acid sequences except for in the C-terminal regions: an elongated sequence, Gly-Thr-Ile-Arg- Ser-Asp-Gly, was found at the C-terminus of CLSI-II. A short-chain analog protein without an N-terminal Asn residue was also detected in each inhibitor preparation. The inhibitors showed significant homology to Kunitz type inhibitors, but differed from them with respect to the half-cystine content. Among five half-cystine residues present in CLSI-III, two disulfide bonds link Cys44 to Cys88 and Cys142 to Cys149, Cys106 being present as a free cysteine residue. Phenylglyoxal treatment abolished the inhibitory activity of CLSI-III, indicating the participation of an Arg residue in the interaction with the enzyme. The reactive-site peptide bond was deduced to be Arg68-Gly69.

[Clinical significance of galactosyltransferase associated with tumor (GAT), a new tumor marker for ovarian cancer--with special reference to the discrimination between ovarian cancer and endometriosis]

We examined GAT, a newly developed tumor marker, in serum samples collected from 1,503 females in six institutions: 387 healthy females, 1,052 patients with gynecological diseases including 311 ovarian cancers, and 64 with nongynecological diseases. Based on the mean value + 2 SD for the healthy females, the cut-off value was set at 16 U/ml. The positive rate of GAT was 2.6% for the healthy females, 7.1% for patients with benign ovarian tumor, 5.6% for those with endometriosis, 47.9% for those with ovarian cancers, 9.3% for those with cervical cancer, and 13.3% for those with endometrial cancer. The false-positive rate of GAT for endometriosis was very low compared with that of the other markers such as CA 125, CA 602, CA 54/61, CA 72-4, STN, SLX examined in this study. The positive predictive value between ovarian cancer and endometriosis was the highest with GAT among the evaluated markers. In the cases in which the CA 125 (CA 602) value is relatively low, discrimination between ovarian cancer and endometriosis is difficult, because these cases include many patients with endometriosis. GAT showed the highest positive predictive value in such cases, so GAT proved to play a complementary role with CA 125 (CA 602). Combination assay with GAT and CA 54/61/CA 72-4/STN or SLX showed higher diagnostic efficiency between ovarian cancer and endometriosis. These results suggest the usefulness of GAT for discrimination between ovarian cancer and endometriosis.

Metabolism of FK506, a potent immunosuppressive agent, by cytochrome P450 3A enzymes in rat, dog and human liver microsomes

The oxidative metabolism of FK506 by liver microsomes and purified cytochrome P450 (P450) enzymes from rats, dogs and humans was studied. The major metabolite formed by liver microsomes from all species was 13-demethylated FK506, named M-I. In adult rats, liver microsomal metabolic activity toward FK506 was higher in males than in females and was stimulated by treatment with P450 3A inducers such as dexamethasone and phenobarbital. In a reconstituted monooxygenase system containing various forms of purified P450 3A enzymes, rat P450 3A2, dog P450 DPB-1 (a form of the P450 3A family) and human P450 3A4 catalyzed FK506 oxidation efficiently in the presence of cytochrome b5, a mixture of phospholipids (dilauroylphosphatidylcholine, dioleoylphosphatidylcholine and phosphatidylserine), and sodium cholate. Rat P450 2C6 and 2D1 and human P450 2CMP also metabolized FK506, with significant lower activity than the P450 3A enzymes, and other rat P450 1A, 2A, 2B, 2C and 2E families including C11 did not show catalytic activities for FK506. Anti-P450 3A2 and anti-P450 3A4 antibodies strongly inhibited FK506 oxidation catalyzed by rat and human liver microsomes, respectively. The formation rate of M-I correlated well with testosterone 2 beta- and 6 beta-hydroxylase activities in rat liver microsomes and with immunoquantified P450 3A4 content, nifedipine oxidase activity, and testosterone 6 beta-hydroxylase activity in human liver microsomes. These in vitro findings indicate that the P450 3A enzymes in liver microsomes from various species of animals, including human, play a major role in the first step oxidation of FK506.

Influence of HLA antigens on reproduction among Japanese population: study of haplotypes in 247 families

Although an increased incidence of shared HLA antigens among couples experiencing recurrent spontaneous abortion or infertility has been observed, antigenic effects remain to be clarified. These effects, which are suspected to exist among fertile couples, were examined in this study. A group of 247 healthy Japanese families and their 682 children, whose HLA antigen haplotypes could be determined, were studied. Haplotypes of the fathers were compared with those of the mothers, and the combination of HLA antigens in the A, B, C and DR loci was determined as antigenic patterns against the mother. Patterns inherited by children were examined and deviations of the patterns were studied according to the natural rule that either of the haplotypes should be inherited at equal rates. Lower rates of children with antigens common with those of the mother, which may show a result of reproductive selection, were observed among only the first born children in the A (p < 0.05) and DR loci (p < 0.01), but rates similar to those expected were observed among the second born and later children. Lower rates were also observed in the B and C loci among all children with no significant difference between groups of the children. The necessity of differing antigenic factors in order to achieve pregnancy in the population was shown. Important effects of HLA antigenicity in reproductive failure are suggested.

Lung cancer risk of GSTM1 null genotype is dependent on the extent of tobacco smoke exposure

Recently, homozygous gene deletion of GSTM1, one of the Mu class glutathione S-transferase isozymes, was found to occur in approximately half of the population of various ethnic origins and has been implicated in tobacco-related carcinogenesis. In the present study we evaluated the risk of GSTM1 null genotype for lung cancer in relation to the extent of tobacco smoke exposure in 178 lung cancer patients (157 males, 21 females) and 201 healthy controls (140 males, 61 females), who were all Japanese and current smokers aged < or = 69 at the time of diagnosis. GSTM1 genotype was determined by polymerase chain reaction. We found GSTM1 gene to be lacking in 45.3% of the control population and demonstrated that the null genotype was aggregated a lot more in the squamous and small cell carcinoma groups (63-64%) than the control group but slightly more in the adenocarcinoma group (54.3%). Furthermore, when male patients and controls were analysed in relation to the degrees (< 800, 800-1200 and > or = 1200) of smoking index (sigma (cigarettes smoked per day) x (years of smoking)], the proportion of GSTM1 null genotype was found to increase progressively in the squamous and small cell carcinoma groups from 42-50% (odds ratio 0.8-1.3) in the patients with smoking index < 800 to 72-75% (odds ratio 3.1-3.7) in the patients with smoking index > or = 1200, while it was unrelated in the adenocarcinoma (50-55%, odds ratio 1.2-1.5) and in the control groups (42-48%). These results support the hypothesis that the GSTM1 null genotype is one of the genetic traits for smoking-related lung cancers, the risk of which, however, appears to be dependent on the extent of tobacco smoke exposure.

Distribution and protein binding of FK506, a potent immunosuppressive macrolide lactone, in human blood and its uptake by erythrocytes

The distribution of FK506 in the blood was estimated in-vitro. At a drug level of 5 ng mL-1, FK506 mainly distributed in erythrocytes (95-98%) in dog, monkey and human blood, and its distribution was affected by drug concentration, temperature, and haematocrit values. In erythrocytes most of FK506 was distributed in cytoplasmic components and was bound strongly to a protein having a molecular weight of 10-11 kDa. The molecular weight of this protein agrees with FK506-binding protein found in various cells. Greater than 98.8% of FK506 was bound to the plasma proteins in all species studied. FK506 bound to various plasma proteins such as lipoproteins, globulins, alpha 1-acid glycoprotein and albumin.

Myricetin and quercetin, the flavonoid constituents of Ginkgo biloba extract, greatly reduce oxidative metabolism in both resting and Ca(2+)-loaded brain neurons

The antioxidant action of myricetin and quercetin, the flavonoid constituents of the extract of Ginkgo biloba (EGb), on oxidative metabolism of brain neurons dissociated from the rats was examined using 2',7'-dichlorofluorescin (DCFH) which is retained within the neuron and then is oxidized by cellular hydrogen peroxide to be highly fluorescent. Incubation with myricetin or quercetin reduced the oxidation of DCFH in resting brain neurons, more profoundly than EGb. Myricetin decreased the oxidative metabolism at concentrations of 3 nM or more. It was 10 nM or more for the case of quercetin. Incubation with each flavonoid constituent also reduced the Ca(2+)-induced increase in the oxidative metabolism without affecting the cellular content of DCFH or the intracellular concentrations of Ca2+. Such an antioxidant action of myricetin or quercetin may be responsible for a part of the beneficial effects of EGb on brain neurons subject to ischemia.

Pharmacokinetics of multiparticulate sustained-release diltiazem preparations in dogs

The in vivo performance of multiparticulate sustained-release diltiazem preparations [HER-SR(A,B,C)] coated with water-insoluble polymer (ethylcellulose), to control the in vitro dissolution rate, was evaluated in dogs. With a decrease in dissolution rate, HER-SR maintained sustained-release characteristics, although the bioavailability decreased slightly. The bioavailability of HER-SR(A,B,C) was comparable with that of a conventional diltiazem tablet (HER). Plasma diltiazem concentrations for the HER-SR preparations were analyzed with a two-fraction absorption model and the pharmacokinetic characteristics were discussed. From the results, it was considered that HER-SR(B) preparation had desirable pharmacokinetic characteristics as sustained-release diltiazem preparations. The absorption site of the slow-release component of HER-SR(B) in the gastrointestinal tract was examined. Almost all of the component had reached the colon within 5 h of administration, the diltiazem content remaining in the component being approximately 60% of the initial amount. Thus, it was shown that the HER-SR(B) preparation had particular absorption characteristics that resulted in the colon being the part of the gastrointestinal tract most receptive to its release. In vivo release profiles of diltiazem from the HER-SR(B) preparation were calculated by the Wagner-Nelson method, and in vitro and in vivo release profiles of HER-SR(B) were further analyzed with a two-fraction release equation. A close correlation of in vitro and in vivo release profiles of HER-SR(B) was found.

Efficacy of recombinant human granulocyte-macrophage colony-stimulating factor for chemotherapy-induced leukopenia in patients with non-small-cell lung cancer

To assess the feasibility and efficacy of rhGM-CSF in ameliorating chemotherapy-induced leukopenia in patients with advanced non-small-cell lung cancer, we conducted a double-blind placebo controlled phase III study in a multicenter setting. Patients were eligible if they had cytologically or histologically proven cancer, no prior chemotherapy, stage IIIB or IV disease, an Eastern Cooperative Oncology Group (ECOG) performance status of 0-2, an age of less than 76 years, and no symptomatic brain metastasis, disseminated bone metastasis, or previous vertebral/pelvic irradiation. The chemotherapy regimen consisted of mitomycin given at 8 mg/m2 on day 1, cisplatin given at 100 mg/m2 on day 1, and vindesine given at 3 mg/m2 i.v. on days 1 and 8 (MVP). If the granulocyte nadir count recorded after the first cycle of MVP was less than 1,000/mm3, patients were randomly assigned to receive recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) or placebo during the second cycle of MVP. The dose of rhGM-CSF was 125 micrograms/m2 given daily s.c. for 14 consecutive days starting on day 2. Of the 52 patients enrolled, 45 were evaluable. The nadir of granulocytes was significantly lower in the placebo group (P = 0.007). The period during which the granulocyte count was less than 1,000/mm3 was significantly longer in the placebo group (median, 6 vs 10 days; P = 0.04). The incidence of adverse effects related to rhGM-CSF, such as fever (> or = 38 degrees C) and skin rash, was significantly higher in the rhGM-CSF group (P = 0.011). The rate of response to chemotherapy did not significantly differ between the two groups. In conclusion, rhGM-CSF reduced the duration of chemotherapy-induced granulocytopenia. The clinical usefulness of this agent may be deminished because of the adverse effects encountered when it is used in combination with a moderately myelotoxic chemotherapy regimen.

[Changes in hemodynamics and catecholamines during single-level exercise at the anaerobic threshold and 120% of the anaerobic threshold in normal subjects]

Exercise training usually involves the sustained performance of exercise at a prescribed intensity. The effects of exercise performed at the anaerobic threshold (AT) have been widely studied. The effects of single-level exercise on catecholamines and cardiac function were assessed at the AT, and at 120% of the AT in eight healthy Japanese men (mean age 21.9 +/- 1.8 years). 1) Symptom-limited exercise testing utilized the ramp protocol with a bicycle ergometer (20 watts/min) for measuring AT and peak oxygen uptake (peak VO2). 2) Exercise testing was repeated on another day, following the same protocol, with blood sampled to measure norepinephrine (NE) and epinephrine (E) in the resting control state and at the AT and peak exercise. 3) Single-level exercise testing at the AT and at 120% of AT utilized the bicycle ergometer on yet another day. Blood for measurement of NE and E was drawn at 3 and 7 min after achieving a steady-state condition. In addition, the cardiac index (CI) and stroke index (SI) were measured by the CO2 rebreathing method. (1) Mean AT and peak VO2 were 18.3 +/- 1.3 and 40.2 +/- 3.0 ml/min/g, respectively. (2) NE and E measured during ramp exercise testing increased rapidly when the intensity of exercise exceeded the AT. NE measured after 3 and 7 min at the AT during single-level exercise equalled 94.7% and 94.5% of the NE value measured at the AT of ramp exercise, respectively. NE measured after 3 and 7 min at 120% of the AT during single-level exercise was 124.7% and 144.7% at the AT of ramp exercise, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Papovavirus detection by electron microscopy in the brain of an elderly patient without overt progressive multifocal leukoencephalopathy

Virions resembling papovavirus were demonstrated in glial cells in the brain of an aged patient without overt progressive multifocal leukoencephalopathy. The patient was not in a severely immunocompromised state. On histological examination, only a few tiny incomplete necrotic foci were found in the subcortical area. These foci were widely dispersed. Rare, swollen oligodendroglial cells and astrocytes in which papovavirus capsid protein (VP-1) was demonstrated immunohistochemically were present around the foci. The two typical types of virus particles i.e. 35 to 40 nm round particles and elongated particles, were observed in the nuclei of the swollen glial cells. The latter were in the minority. Distinct crystals were also found in the nuclei. The centre-to-centre distance of the particles in the crystals, about 40 nm, and the electron-opaque spots of the round-shaped virions and of the elongated particles, were indicative of structural subunits of papovavirus capsids. This case provides further evidence that papovavirus, possibly JC virus, may be reactivated in the brains of aged patients who are not in an immunocompromised state.

A study of dose escalation of teniposide (VM-26) plus cisplatin (CDDP) with recombinant human granulocyte colony-stimulating factor (rhG-CSF) in patients with advanced small cell lung cancer

A dose escalation study of teniposide (VM-26) plus cisplatin (CDDP) was carried out using recombinant human granulocyte colony-stimulating factor (rhG-CSF) in 46 previously untreated patients with advanced small cell lung cancer (SCLC). The dose of CDDP was 80 mg/m2/day intravenously (i.v.) (day 1) and VM-26 was escalated from 60 mg/m2/day to 80, 100 and 120 mg/m2/day i.v. x 5 days for four cycles. The dose of rhG-CSF was 90 micrograms/m2/day subcutaneously for 13 days. The feasibility of the regimen at the starting dose level of VM-26 with or without rhG-CSF was initially examined in 10 patients chosen through random allocation. WHO grade 4 neutropenia was observed in 17% (three out of 18 courses) of patients in the rhG-CSF group and in 63% (12 out of 19 courses) of the control group (P < 0.01). The number of patients with febrile episodes (> 38 degrees C) over the four courses of chemotherapy was 1 in the rhG-CSF group and 4 in the control group. According to these results, all 36 patients received rhG-CSF in the dose escalation stage. The incidence of WHO grade 4 neutropenia at the dose levels of 60, 80, 100 and 120 mg/m2/day of VM-26 was 66, 57, 76 and 85%, respectively (P > 0.1). The incidence of grade 4 thrombocytopenia was 19, 31, 18 and 46%, respectively (P > 0.1). The overall response rate was 100% in patients with limited stage SCLC and 83% in patients with extensive stage SCLC. The actual administered VM-26 dose per week at the dose level of 100 mg/m2/day was 1.6-fold higher than the planned starting dose (60 mg/m2/day) per week. At the dose level of 120 mg/m2/day, 50% of patients developed WHO grade 4 leucopenia, which lasted longer than 1 week and 67% of the patients had WHO grade 3 or 4 diarrhoea. At this same dose, all patients had at least one febrile episode (> 38 degrees C), and 1 patient died of cerebral bleeding with severe thrombocytopenia. The median survival time of all patients was 451 days (411 days, extensive disease; 497 days, limited disease). VM-26 plus CDDP with rhG-CSF was active in previously untreated patients with SCLC. The recommended dose of VM-26 in combination with CDDP for a phase II study is 100 mg/m2/day for 5 days with rhG-CSF support.

An organic acid-induced sigmoidal release system for oral controlled-release preparations

To achieve time-controlled or site-specific drug delivery in the gastrointestinal tract, a sigmoidal release system (SRS) was developed, which achieved a prolonged lag time, followed by rapid release. The theophylline beads with a thick Eudragit RS film coating showed very low drug release in water, whereas the release rate increased considerably in organic acid solutions. A hydration study of Eudragit RS films suggested that the increase in drug release was attributable to structural changes of the film induced by polymer-acid interactions. When succinic acid was incorporated into the core of Eudragit RS-coated theophylline beads, the drug release profile showed a typical sigmoidal pattern. SRS beads containing acetaminophen were also prepared by the same technique. Again, a sigmoidal release pattern was observed in which the lag time was prolonged with an increase in the coating level, whereas the drug release rate thereafter was almost constant irrespective of the coating level. Acetaminophen-containing SRS beads with different coating thickness were orally administered to beagle dogs. The drug plasma concentration curves showed lag periods similar to the in vitro lag time.