Effectiveness of combination tocilizumab and glucocorticoids as an induction therapy in patients with Takayasu arteritis: An observational study

BACKGROUND

The efficacy of tocilizumab (TCZ) in the treatment of Takayasu arteritis (TA) was demonstrated in randomized controlled trials. The objective of this study was to analyse the effectiveness of combining TCZ with glucocorticoids (GC) as induction therapy in patients with TA.

METHOD

This was a retrospective observational study including 32 patients with newly diagnosed TA. Clinical effectiveness of TCZ in maintaining relapse-free remission and GC-tapering were compared between patients who were treated with TCZ plus GC and those who were treated with GC with or without immunosuppressants.

RESULTS

The study comprised 32 patients (27 women/5 men) with a median age of 25.5 years (range, 13-72). In the TCZ group (n = 14), patients received TCZ in combination with GC as an induction therapy. In the non-TCZ group (n = 18), patients were treated with single-agent GC or GC plus immunosuppressant. In the matched analysis, relapse-free survival rate was significantly higher in the TCZ group as compared to the non-TCZ group during GC taper.

CONCLUSION

TCZ, in combination with GC, would be an effective alternative induction regimen for patients with TA.

Development of Acute Promyelocytic Leukemia in a Patient with Granulomatosis with Polyangiitis: A Case Report

Granulomatosis with polyangiitis (GPA) is a rare disorder of unknown etiology, which is characterized by necrotizing granulomatous inflammation of the upper respiratory system and kidneys. Immunosuppressive treatment (cyclophosphamide or azathioprine with glucocorticoids) improved the outcome of GPA, however, latent comorbidity (cancers and hematologic malignancies) has become more prevalent in recent years. Here, we present a first case of the patient with GPA complicated by acute promyelocytic leukemia (APL) successfully treated with molecular-targeted therapy. A 77-year-old female was referred to our hospital for nasal obstruction, hearing loss, and fever. Otorhinolaryngological investigation revealed otitis media, and head computed tomography (CT) showed paranasal mucosal thickening with septal perforation. Chest CT showed cavitary granulomatous lesions in both lungs. Biopsy of the nasal mucosa revealed granulomatous lesions, and the patient was finally diagnosed with GPA. Oral administration of prednisolone 50 mg/day was initiated, and oral azathioprine (50 mg/day) was added. After 26 months of azathioprine initiation, pancytopenia developed and azathioprine was stopped. Then sudden elevated levels of blasts appeared in the hemogram (blasts 11%). She was diagnosed with APL via bone marrow examination which revealed plenty of faggot cells with Auer rods and chromosomal mutation. The patient was started on all-trans retinoic acid 60 mg/day following arsenic trioxide 7 mg/day in consideration of elderly onset. Complete remission was achieved and oral prednisolone was successfully reduced to 15 mg/day without a major relapse of GPA. Because GPA can be complicated by APL even during maintenance treatment using azathioprine, careful monitoring should be performed in such patients.

Case Report: Coexistence of Multiple Myeloma and Auricular Chondritis in VEXAS Syndrome

Vacuoles, E1 enzyme, X-linked, autoinflammatory, somatic (VEXAS) syndrome is an inflammatory disorder caused by somatic UBA1 variants, which are sometimes associated with hematological disorders, including myelodysplastic syndrome (MDS). VEXAS syndrome often overlaps with rheumatic diseases, including relapsing polychondritis. Here, we describe a case of VEXAS syndrome with auricular chondritis and exceptional multiple myeloma (MM). An 83-year-old man was diagnosed with MM, which was treated once by lenalidomide hydrate obtaining a partial response, but the patient did not desire further aggressive therapy. Although the treatment was effective, progressive macrocytic anemia and inflammation of both the ears emerged over the following 2 months. The histological examination of the auricle skin revealed that the perichondrial area was infiltrated by inflammatory cells, leading to the diagnosis of auricular chondritis. He was treated with oral prednisolone 40 mg/day, and his symptoms rapidly resolved. The re-evaluation of the histopathological bone marrow findings revealed vacuoles in the myeloid precursor cells without myelodysplasia-related changes. Sanger sequencing of UBA1 was performed using genomic DNA from peripheral blood leukocytes and revealed a somatic variant (c.122T>C:p.Met41Thr) consistent with VEXAS syndrome. This demonstrates that patients with chondritis can have complications with MM despite the absence of underlying MDS. A strong association exists between UBA1 variants and the risk of MDS; however, it remains elusive whether somatic UBA1 variants contribute to the development of plasma cell dyscrasia without MDS. Hence, we discuss the possible relationship between auricular chondritis and MM on a background of VEXAS syndrome.

Total Hip Joint Replacement in a Patient with Colchicine-Resistant Familial Mediterranean Fever under Canakinumab Treatment

Familial Mediterranean fever (FMF) is a hereditary autoinflammatory disease characterized by recurrent episodes of fever and serositis. Periodic febrile attack can be managed with biologic medication in colchicine-resistant FMF patients, however, no reports or guidelines exist regarding the postoperative management of elective joint surgery in these patients. Although it is not clear how FMF attacks are triggered, they may be precipitated by stress including anesthesia or surgery. This study reports the case of a 51-year-old FMF patient who received total hip replacement under canakinumab (a specific interleukin-1β monoclonal antibody) treatment. He had highly active FMF, which was resistant to colchicine; however, his recurrent febrile attack with serositis was successfully controlled with canakinumab. Four months later from the start of canakinumab treatment, his hip osteoarthritis was required for total hip replacement (THR) because of the traumatic fracture. THR was successfully done and FMF attack was not occurred after this elective surgery. Discontinuation of canakinumab 3 weeks before surgery and resumption 6 weeks after led to favorable outcome without complications. This case addresses the differential management concerning stopping and restating of canakinumab in the perioperative setting in contrast to the other biologics such as tumor necrosis factor-α (TNF-α) or interleukin-6 (IL-6) blocking agents. This case report suggests that canakinumab may represent a safe and effective therapy for the colchicine-resistant FMF, even in the patients requiring THR therapy.

Adult-Onset Still's Disease Complicated by Immunoglobulin A Vasculitis and anti-CCP Antibody-Positive Arthritis

A 38-year-old male was admitted to our hospital for arthralgia, fever, skin rash, and purpura. He was diagnosed as having adult-onset Still's disease (AOSD) based on Yamaguchi's criteria. Skin biopsy revealed immunoglobulin A (IgA) vasculitis. He was also found to have anti-cyclic citrullinated peptide (CCP) antibody-positive inflammatory arthritis on a shoulder joint, however he did not fulfill classification criteria for rheumatoid arthritis. Elevated serum cytokine such as serum IL-18 supported the diagnosis of AOSD. His symptoms improved with 40 mg of prednisolone plus cyclosporin A (200 mg/day). Two years after hospitalization, AOSD was relapsed with pleurisy and hyperferritinemia. Finally, he was diagnosed with multicyclic systemic type of AOSD complicated by IgA vasculitis and seropositivity of anti-CCP antibody. Clinicians need to consider the complication of multiple rheumatic diseases, even if the disease-specific autoantibody is positive.

Association between inflammatory cytokines and immune-checkpoint molecule in rheumatoid arthritis

Background

Anti-citrullinated peptide antibodies (ACPA) and inflammatory cytokines play important roles in the development of rheumatoid arthritis (RA). T cell immunoglobulin and mucin–domain containing–3 (TIM–3) is an immune-checkpoint molecule involved in inhibitory signaling. Galectin–9 (Gal–9) mediated ligation of TIM–3 induces the amelioration of autoimmune diseases. TIM–3 is expressed in synovial osteoclasts and involved in the rheumatoid bone destruction. The aim of this study was to investigate the relationships between inflammatory cytokines and immune–checkpoint molecules in RA patients.

Methods

Serum levels of interleukin–6 (IL–6), tumor necrosis factor–α (TNF–α), soluble TIM–3 (sTIM–3) and Gal–9 were determined by ELISA. Patients were stratified into two groups based on ACPA titers: low-medium ACPA (ACPA <200 U/mL) and high ACPA (ACPA ≥200 U/mL). Serum levels of cytokines or immune-checkpoint molecules were evaluated between RA patients with low-medium ACPA titers and high ACPA titers.

Results

Elevated serum levels of inflammatory cytokines were correlated with DAS28–ESR in RA patients. Although serum levels of sTIM–3 were elevated in RA patients, significant correlations between sTIM–3 and cytokines (IL–6 or TNF–α) were observed exclusively in RA patients with low-medium ACPA titers (<200 U/mL). Serum levels of IL–6 and TNF–α levels were significantly correlated with elevated Gal–9 levels regardless of ACPA status. A significant correlation between IL–6 and Gal–9 was observed in RA patients without advanced joint damage. Conversely, a significant correlation between TNF–α and Gal–9 was observed in RA patients with advanced joint damage.

Conclusions

Our data indicated that there are positive correlations between circulating inflammatory cytokines and checkpoint molecules in RA patients and these interactions can be modulated by ACPA status or joint damage stage.

Immunoglobulin A Vasculitis in a Japanese Patient with Complete Familial Mediterranean Fever Carrying MEFV Exon 10 Mutation

Immunoglobulin A (IgA) vasculitis is a systemic small-vessel vasculitis involving the skin, kidney, joints, and gastrointestinal tract. Familial Mediterranean fever (FMF) is the most common autoinflammatory disease characterized by periodic fever, peritonitis, pleuritis, or arthritis. It is well known that FMF may coexist with vasculitis, especially small and medium vessel vasculitis. Here we present a Japanese male patient with FMF who later developed IgA vasculitis and a relapsing disease course. A 51-year-old Japanese male was referred because of upper abdominal pain, arthralgia, and bilateral purpura of the lower limbs. He fulfilled the criteria for IgA vasculitis, which was successfully treated by corticosteroid and immunosuppressive therapy. He had a medical history of periodic fever since the age of 10 years old. The Mediterranean fever (MEFV) gene analysis revealed that he was heterozygous for M694I and E148Q mutations. Colchicine therapy resolved his periodic febrile attacks. To our knowledge, coexistence of FMF with IgA vasculitis has not been reported in East Asia, including Japan. Our case suggests that MEFV gene exon 10 mutations could be related to the development of IgA vasculitis and affects its clinical course.

Solution structure of the ribosome recycling factor from Aquifex aeolicus

The solution structure of ribosome recycling factor (RRF) from hyperthermophilic bacterium, Aquifex aeolicus, was determined by heteronuclear multidimensional NMR spectroscopy. Fifteen structures were calculated using restraints derived from NOE, J-coupling, and T1/T2 anisotropies. The resulting structure has an overall L-shaped conformation with two domains and is similar to that of a tRNA molecule. The domain I (corresponding to the anticodon stem of tRNA) is a rigid three alpha-helix bundle. Being slightly different from usual coiled-coil arrangements, each helix of domain I is not twisted but straight and parallel to the main axis. The domain II (corresponding to the portion with the CCA end of tRNA) is an alpha/beta domain with an alpha-helix and two beta-sheets, that has some flexible regions. The backbone atomic root-mean-square deviation (rmsd) values of both domains were 0.7 A when calculated separately, which is smaller than that of the molecule as a whole (1.4 A). Measurement of 15N-[1H] NOE values show that the residues in the corner of the L-shaped molecule are undergoing fast internal motion. These results indicate that the joint region between two domains contributes to the fluctuation in the orientation of two domains. Thus, it was shown that RRF remains the tRNA mimicry in solution where it functions.

Interaction of ribosome recycling factor and elongation factor EF-G with E. coli ribosomes studied by the surface plasmon resonance technique

BACKGROUND

Ribosome recycling factor (RRF), in concert with elongation factor EF-G, is required for disassembly of the post-termination complex of a ribosome after the release of polypeptides. How RRF dissociates the complex has long been puzzling. Crystal structures of RRF molecules have been solved recently and shown to mimic a transfer RNA (tRNA) shape, which prompted us to examine whether RRF binds to the ribosome as tRNA does.

RESULTS

The formation of ribosome complexes on the surface-coupled RRF and elongation factor EF-G of Escherichia coli was monitored in real time with a BIACORE 2000 instrument based on the surface plasmon resonance technique. RRF interacted with 70S ribosomes as well as 50S and 30S subunits, although it interacted preferentially with 50S subunits, which was clearly seen under high but physiological ionic conditions. This 50S interaction was diminished by a single amino acid substitutions for Arg132 of RRF, which did not appreciably affect the protein folding but nullified the activity in vivo and in vitro. Moreover, a set of antibiotics that inhibited the RRF-50S interaction were also inhibitory to the polysome breakdown activity of RRF in vitro. The BIACORE technique also worked very well in demonstrating the action of the antibiotics thiostrepton and fusidic acid, which are inhibitory to the RRF function by freezing the pre- and post-translocation intermediates catalysed by EF-G.

CONCLUSIONS

These results suggest that the preferential interplay of RRF with the 50S subunit may be of biological significance, probably reflecting the mode of RRF action. The BIACORE technique proved useful for real-time monitoring of the interaction between the ribosome and translation factors, as well as for screening of potential inhibitors for ribosome recycling factor.

Monamidocin, a novel fibrinogen receptor antagonist. II. Biological activity and structure-activity relationships

Monamidocin, a fibrinogen receptor binding inhibitor produced by Streptomyces sp. NR 0637, inhibits the binding of fibrinogen to its receptor with an IC50 of 0.21 microM. It also inhibits ADP-collagen- and thrombin-induced aggregation of human platelet with IC50S of 46, 30, and 77 microM, respectively. To obtain more potent inhibitors, twenty analogs have been synthesized, among which N-[(R)-5-guanidino-2-hydroxypentanoyl]-L-tyrosine is the most potent. It inhibits the binding of fibrinogen to its receptors with an IC50 of 0.022 microM and is about ten times more potent than monamidocin.

Monamidocin, a novel fibrinogen receptor antagonist. I. Production isolation, characterization and structural elucidation

Monamidocin, a novel fibrinogen receptor antagonist, has been isolated from the culture broth of Streptomyces sp. NR 0637 BY carbon adsorption, n-BuOH extraction, SP-Toyopearl, silica gel 60 silanised and Sephadex LH-20 column chromatographies and preparative HPLC. The molecular formula of monamidocin has been determined to be C15H22N4O4 from HRFAB-MS and 13C NMR spectral data. The structure of monamidocin has been determined to be N-[(S)-5-guanidino-2-hydroxypentanoyl]-L-phenylalanine by 2D NMR experiments.

Sulfobacins A and B, novel von Willebrand factor receptor antagonists. II. Structural elucidation

Sulfobacins A and B are novel von Willebrand factor (vWF) receptor antagonists produced by Chryseobacterium sp. NR 2993. The structures of sulfobacins A and B have been determined to be (2R,3R)-3-hydroxy-2-[(R)-3-hydroxy-15-methylhexadecanamido]-15- methylhexadecanesulfonic acid and (2R,3R)-3-hydroxy-15-methyl-2-[13-methyltetradecanamido]- hexadecanesulfonic acid, respectively, by various 2D NMR experiments and by methanolysis. The absolute configurations of the sulfobacins were determined by a modified MOSHER's method. The structures are related to sulfonolipids, major components of the cell envelope of gliding bacteria of the genus Cytophaga.

Sulfobacins A and B, novel von Willebrand factor receptor antagonists. I. Production, isolation, characterization and biological activities

Sulfobacins A and B, novel von Willebrand factor (vWF) receptor antagonists, have been isolated from the culture broth of Chryseobacterium sp. (Flavobacterium sp.) NR 2993 by ethyl acetate extraction, and by Sephadex LH-20 and silica gel column chromatographies. The physico-chemical properties of the sulfobacins indicate that their structures are completely different from that of aurintricarboxylic acid, the one known vWF receptor antagonist. Sulfobacins A and B inhibit the binding of vWF to its receptor with IC50S of 0.47 and 2.2 microM, respectively. Sulfobacin A also inhibits ristocetin-induced agglutination in human platelets fixed with paraformaldehyde with an IC50 of 0.58 microM.

Panclicins, novel pancreatic lipase inhibitors. II. Structural elucidation

Panclicins A-E are novel and potent pancreatic lipase inhibitors produced by Streptomyces sp. NR 0619. Their structures have been elucidated based on NMR and FAB-MS experiments. The relative configurations have also been determined by NMR experiments. The absolute stereochemistry has been determined by the chiral HPLC analysis of the hydrolysates of panclicins A and B and by modified Mosher's method on a derivative of panclicin A. They are structurally related to beta-lactone esterase inhibitors of microbial origin, lipstatin, valilactone, ebelactones and esterastin. Panclicins also contain a beta-lactone structure with two alkyl chains, one of which has an N-formylalanyloxy or N-formylglycyloxy substituent.

Bacithrocins A, B and C, novel thrombin inhibitors

Novel thrombin inhibitors, bacithrocins A, B and C, have been isolated from the culture broth of Bacillus laterosporus Laubach NR 2988. The structures of these inhibitors have been determined to be N-acyl-L-phenylalanyl-DL-arginal by the 2D-NMR experiments on their oxidation products and by amino acid analysis. Bacithrocin A inhibits thrombin, factor Xa and trypsin with IC50s of 48, 13 and 0.65 microM, respectively, which are similar to those of bacithrocins B and C. Bacithrocins prolong the clotting time induced by thrombin and factor Xa.

Fusarium merismoides Corda NR 6356, the source of the protein kinase C inhibitor, azepinostatin. Taxonomy, yield improvement, fermentation and biological activity

Fungal strain NR 6356, Fusarium merismoides Corda, was discovered as the source of the protein kinase C (PKC) inhibitor, azepinostatin. The strain was identified based on its growth on potato sucrose agar, slender conidial shape, characteristic polyphialide and production of abundant chlamydospores. Fusarium aquaeductuum Lagh. IMI 103658 and Fusarium sp. NR 7222 were also found to produce the same inhibitor. After single colony isolation and medium optimization trials, a more than 30-fold increase in the production of azepinostatin over the original culture was achieved. Azepinostatin selectively and potently inhibited rat brain PKC with an IC50 value of 70 nM. Other enzymes utilizing ATP, including hexokinase, were not affected. The Ki of azepinostatin for PKC was 0.5 nM. The inhibition of PKC was competitive with ATP and uncompetitive with histone.

Cyclothialidine, a novel DNA gyrase inhibitor. II. Isolation, characterization and structure elucidation

Cyclothialidine is a novel DNA gyrase inhibitor produced by Streptomyces filipinensis NR 0484. It was isolated from the culture broth by charcoal adsorption, Diaion HP-21, Amberlite CG-50, DEAE Toyopearl, and Toyopearl HW-40 SF column chromatography. The structure of cyclothialidine was determined to be a unique twelve membered lactone by amino acid analysis and various 2D-NMR experiments. Cyclothialidine inhibited Escherichia coli DNA gyrase with an IC50 of 30 ng/ml.

Hispidospermidin, a novel phospholipase C inhibitor produced by Chaetosphaeronema hispidulum (Cda) Moesz NR 7127. II. Isolation, characterization and structural elucidation

Hispidospermidin (1) is a novel phospholipase C inhibitor produced by Chaetosphaeronema hispidulum (Cda) Moesz NR 7127. Its structure (C25H47N3O) has been elucidated as a cage compound with a trimethylspermidine side chain based on various NMR studies, including 1H-1H COSY, 13C-1H COSY, HOHAHA, HMBC, COLOC and long range J C-H resolved 2D spectroscopy. The absolute configuration of 1 has been elucidated by modified Mosher's method on the (R)- and (S)-MTPA amides of a derivative of 1.

Tetrafibricin, a novel fibrinogen receptor antagonist. II. Structural elucidation

The structure of tetrafibricin, a novel and potent fibrinogen receptor antagonist isolated from the culture broth of Streptomyces neyagawaensis NR0577, was determined. Tetrafibricin has a unique structure containing primary amine, conjugated tetraenoic acid, and polyhydroxy functionalities that is biosynthetically related to the polyene macrolide antibiotics.

Tetrafibricin, a novel fibrinogen receptor antagonist. I. Taxonomy, fermentation, isolation, characterization and biological activities

Tetrafibricin is a novel fibrinogen receptor antagonist produced by Streptomyces neyagawaensis NR0577. It was isolated from the culture broth by Diaion HP-21 adsorption, MeOH extraction, MCI GEL CHP-20P column chromatography, preparative HPLC and Toyopearl HW-40 SF column chromatography. The physico-chemical properties of tetrafibricin indicated that the structure of tetrafibricin is different from the known peptide fibrinogen receptor antagonists and closely related to the polyene macrolide antibiotics. Tetrafibricin strongly inhibited the binding of fibrinogen to its receptors with an IC50 of 46 nM. It also inhibited ADP-, collagen-, and thrombin-induced aggregation of human platelets with IC50s of 5.6, 11.0 and 7.6 microM, respectively.

Tetronothiodin, a novel cholecystokinin type-B receptor antagonist produced by Streptomyces sp. NR0489. II. Isolation, characterization and biological activities

A novel cholecystokinin type-B receptor antagonist named tetronothiodin has been isolated by column chromatography and preparative HPLC from the fermentation broth of Streptomyces sp. NR0489. Tetronothiodin inhibited the binding of CCK8 (C-terminal octapeptide of cholecystokinin) to rat cerebral cortex membranes (CCK type-B receptors) with an IC50 of 3.6 nM, whereas it did not inhibit CCK8 binding to rat pancreatic membranes (CCK type-A receptors). It also inhibited CCK8 induced Ca2+ mobilization in GH3 cells, a rat anterior pituitary cell line, but was without effect on the basal cytosolic Ca2+ concentration. This finding indicated tetronothiodin was an antagonist of CCK type-B receptors.

Tetronothiodin, a novel cholecystokinin type-B receptor antagonist produced by Streptomyces sp. NR0489. III. Structural elucidation

Tetronothiodin (1) is a potent and selective cholecystokinin type B (CCK-B) receptor antagonist produced by Streptomyces sp. NR0489. Its structure was elucidated to be a macrocyclic compound comprising cyclohexene, alpha-acyltetronic acid and tetrahydrothiophene moieties based on various 2D NMR experiments on 1 and its dihydro derivative. The stereochemistries for the cyclohexene and tetrahydrothiophene rings were elucidated based on the analysis of NOEs obtained by NOESY experiments and NOE difference spectroscopy. The relative configuration of the cyclohexene moiety in 1 was revealed to be the same as that of the corresponding part in kijanimicin and chlorothricin, which can be structurally related to 1 in terms of their containing a cyclohexene ring with a spirotetronic acid in the molecule.

Structural studies on avidinorubicin, a novel anthracycline with platelet aggregation inhibitory activity

Avidinorubicin (MW 1,214, C60H86N4O22) was isolated from the cultured broth of strain NR0576 (which was identified as Streptomyces avidinii Stapley et al.) by butyl alcohol extraction, Sephadex LH-20 column chromatography and preparative HPLC. Avidinorubicin inhibited thrombin-induced platelet aggregation with an IC50 being 7.9 microM and was determined to be a novel anthracycline possessing two units of a new aminosugar, avidinosamine, in place of two decilonitrose groups in decilorubicin.

Cyclothiazomycin, a novel polythiazole-containing peptide with renin inhibitory activity. Taxonomy, fermentation, isolation and physico-chemical characterization

Cyclothiazomycin is a novel renin inhibitor produced by Streptomyces sp. NR0516. It was isolated from fermentation broth by extraction with butyl alcohol, QAE-Toyopearl column chromatography and preparative HPLC. Cyclothiazomycin, which was determined to be a unique polythiazole-containing bicyclic peptide, exhibited inhibitory activity against human plasma renin with IC50 being 1.7 microM.

Comparative studies on the antitumor and immunosuppressive effects of the new fluorouracil derivative N4-trimethoxybenzoyl-5'-deoxy-5-fluorocytidine and its parent drug 5'-deoxy-5-fluorouridine

N4-Trimethoxybenzoyl-5'-deoxy-5-fluorocytidine (Ro 09-1390), a new prodrug of 5'-deoxy-5-fluorouridine (5'-dFUrd), was synthesized for the purpose of finding a drug with less intestinal toxicity than the parent compound. The present study compared the antitumor activity and immunotoxicity of Ro 09-1390 with those of 5'-dFUrd, 5-fluorouracil (5-FUra) and tegafur in various transplantable tumor models. The antitumor efficacy of Ro 09-1390 was comparable to 5'-dFUrd and these two agents were much more effective than the others. However, Ro 09-1390 was much less toxic to the intestinal tract and less immunosuppressive in both humoral and cellular immune reactions than 5'-dFUrd. Consequently, Ro 09-1390 showed higher therapeutic indices and higher efficacy than 5'-dFUrd at high dosages. The antitumor spectrum of Ro 09-1390 was somewhat different from that of 5'-dFUrd, though it shows the efficacy after it converts to 5'-dFUrd. The activity of Ro 09-1390 was partly associated with cytidine deaminase in the tumors treated. Ro 09-1390 appeared to be more effective against tumors with a high concentration of the enzyme by which the major metabolite 5'-deoxy-5-fluorocytidine (5'-dFCyd) is metabolized to 5'-dFUrd.

Comparative antitumor activity and intestinal toxicity of 5'-deoxy-5-fluorouridine and its prodrug trimethoxybenzoyl-5'-deoxy-5-fluorocytidine

N4-Trimethoxybenzoyl-5'-deoxy-5-fluorocytidine (Ro 09-1390), a prodrug of the cytostatic 5'-deoxy-5-fluorouridine (5'-DFUR), was synthesized with the aim of reducing of the dose-limiting toxicity of 5'-DFUR, which is diarrhea. In mice bearing Lewis lung carcinoma, 5'-DFUR given po produced a substantial amount of 5-fluorouracil (5-FU) in the intestinal tract as well as tumors, where the enzyme pyrimidine nucleoside phosphorylase, essential for conversion of 5'-DFUR to 5-FU, is predominantly located. With the oral administration of Ro 09-1390 only a small amount of 5-FU was formed in the intestine; however, the administration of Ro 09-1390 and 5'-DFUR at the same dose produced similar amounts of 5-FU in tumor tissues. These differences in metabolism were reflected in their toxicity and antitumor efficacy. The administration of 5'-DFUR resulted in damage to the intestinal mucosal membrane and diarrhea in normal mice, whereas Ro 09-1390 was much less toxic to the intestinal tract. As regards antitumor activity, Ro 09-1390 and 5'-DFUR at equivalent doses inhibited the growth of Lewis lung carcinoma to similar extents. Since Ro 09-1390 was much less toxic to the intestinal tract than 5'-DFUR, mice bearing Lewis lung carcinoma could be given Ro 09-1390 daily over a longer period and at a higher dose, resulting in a longer survival time.

Penitricin, a new class of antibiotic produced by Penicillium aculeatum. II. Isolation and characterization

A novel antibiotic, penitricin, Ro 09-0804, has been produced in the culture filtrate of Penicillium aculeatum NR 5165. This antibiotic was purified by repeated extraction of culture filtrate with 1-butanol, and passage of the crude extracts through Sephadex G-10, followed by HPLC (Shodex Ionpak S-801). Physico-chemical characterization was made on penitricin, while two open-ringed penitricins B and C co-produced by the producer strain were also identified.

New alpha-amylase inhibitor, trestatins. IV. Taxonomy of the producing strains and fermentation of trestatin A

Taxonomic characteristics of strains NR-320-OM7HB and NR-320-OM7HBS producing a homologous series of new alpha-amylase inhibitors named trestatins are described, together with the comparison of these strains with similar Streptomyces species by DNA-DNA hybridization. A new species, Streptomyces dimorphogenes sp. nov. Watanabe and Maruyama is proposed as a result of the studies. The type strain of this species is strain NR-320-OM7HB (ATCC 31484), and the morphovar is strain NR-320-OM7HBS (ATCC 31485). The productivity of trestatin A, major and most active component, using these two strains in flask culture is also presented.

New alpha-amylase inhibitor, trestatins. II. Structure determination of trestatins A, B and C

The structures of trestatins A (C56H94N2O40), B (C37H63NO28) and C (C75H125N3O52), new basic oligosaccharides with potent inhibitory activity against various alpha-amylases, have been shown by spectroscopic and chemical methods to be 1, 2 and 3, respectively.

New alpha-amylase inhibitor, trestatins. I. Isolation, characterization and biological activities of trestatins A, B and C

Trestatin complex which exhibited a potent inhibitory activity on various alpha-amylases has been isolated from the culture filtrate of Streptomyces dimorphogenes nov. sp. NR-320-OM7HB. Three major components, trestatins A, B and C, have been purified by adsorption and ion-exchange chromatography. Their spectral and chemical properties suggested that trestatins were novel basic oligosaccharide homologues each characterized by the possession of a trehalose moiety at the non-reducing end of the molecule.

Microbial Resolution of α-Hydroxy Acids by Enantiospecifically Dehydrogenating Bacteria from Soil

Thirty-three bacterial strains were isolated from soil, utilizing optically asymmetric degradation of dl -2-hydroxy-4-methylpentanoic acid ( dl -HMPA) as the screening probe. Those strains were distributed in the following group and genera: Coryneform and Bacillus, Pseudomonas, and Streptomyces. Among them, the most potent strains, Bacillus freudenreichii NRS-137KH20B and Brevibacterium albidum NRS-130KH20B, could perform the resolution of more than 30 g of dl -HMPA per liter within 4 to 5 days of fermentation. Optically pure l - and d -HMPA enantiomers were obtained in more than 80% theoretical yield, whereas the transformed enantiomer was almost quantitatively recovered as 2-oxo-4-methyl-pentanoic acid in the culture broth. The enantiospecific dehydrogenation responsible for this resolution reaction had a rather wide substrate specificity on straight or branched aliphatic C 4 to C 16 2-hydroxy acids, exhibiting the optima at chain lengths of either C 7 or C 5 , although the enantiospecificity was not changed by chain length. The process was thus successfully extended to the preparation of optically pure C 5 to C 9 2-hydroxy acids.

Regio-Selective 10-Hydroxylation of Patchoulol, a Sesquiterpene, by Pithomyces Species

Of some 350 microorganisms screened, four strains of Pithomyces species were found to carry out regio-selective hydroxylation of patchoulol, a sesquiterpene, to 10-hydroxypatchoulol: Pithomyces sp. NRJ201, P. chartarum NRJ210, and, to a lesser extent, P. cynodontis ATCC 26150 and P. atro-olivaceus IFO 6651 were found to catalyze this reaction. A method has been developed by which 10-hydroxypatchoulol was obtained in 25 to 45% yields in 1- to 5-liter fermentation jars at 2 to 4 g of patchoulol per liter and isolated as pure material in 30% yields.

A new antibiotic, fumaramidmycin. II. Isolation, structure and syntheses

A new antibiotic fumaramidmycin produced by Streptomyces kurssanovii NR-7GG1 was isolated as colorless crystals. The structure was shown to be N-(phenylacetyl) fumaramide. Starting from fumaramic acid, fumaramidmycin has been synthesized in good yield, in which the key stage involves N-acylated imino ether formation followed by mild acid hydrolysis. Five analogues of fumaramidmycin have also been prepared.