Phase I study of OPB-51602, an oral inhibitor of signal transducer and activator of transcription 3, in patients with relapsed/refractory hematological malignancies

We carried out a multicenter dose-escalation phase I study of oral OPB-51602, a signal transducer and activator of transcription 3 phosphorylation inhibitor, in patients with relapsed or refractory hematological malignancies to evaluate the safety, maximum tolerated dose (MTD), pharmacokinetics, and preliminary antitumor activity. Twenty patients were treated with OPB-51602 at doses of 1, 2, 3, 4, and 6 mg in the “3 + 3” dose escalation design. The most common treatment-related adverse events included nausea (55%), peripheral sensory neuropathy (45%), and diarrhea (40%). The most frequently observed grade 3 or 4 drug-related adverse events were neutropenia (20%), leukopenia (15%), lymphopenia (10%), and thrombocytopenia (10%). The MTD was 6 mg, with dose-limiting toxicities of grade 3 lactic acidosis and increased blood lactic acid levels observed in one of three patients and grade 1–2 peripheral neuropathy in three of three patients. The recommended dose was determined to be 4 mg. OPB-51602 was rapidly absorbed, and exposure tended to increase in a dose-dependent manner. Accumulation of OPB-51602 was seen with 4 weeks of multiple treatments. No clear therapeutic response was observed. Durable stable disease was observed in two patients with acute myeloid leukemia and one with myeloma. In conclusion, the MTD of OPB-51602 was 6 mg. OPB-51602 was safe and well tolerated in a dose range of 1–4 mg. However, long-term administration at higher doses was difficult with the daily dosing schedule, and no response was seen. Therefore, further clinical development of OPB-51602 for hematological malignancies with a daily dosing schedule was terminated.

A novel method for rapid detection of Streptococcus pneumoniae antigen in sputum and its application in adult respiratory tract infections

A highly sensitive immunochromatography test kit, ODK0501, was developed using specific polyclonal antibodies against the C-polysaccharide moiety of Streptococcus pneumoniae for the rapid detection of S. pneumoniae antigen in sputum samples. The clinical utility of ODK0501 for this detection was evaluated prospectively in 52 adult patients with respiratory infections and compared with that of a urinary antigen detection kit. Overall, 21 patients (40.4 %) showed positive results with ODK0501, compared with 16 patients (30.8 %) using the urinary antigen detection kit, and S. pneumoniae was cultured from 18 patients. ODK0501 and the urinary antigen detection kit exhibited a sensitivity of 94.4 and 55.6 % (P<0.01), respectively, and a specificity of 88.2 and 82.4 %, respectively. Eleven of thirteen patients with conflicting results between the two test kits exhibited consistent results for sputum cultures. Moreover, eight out of nine patients positive for ODK0501 and negative for the urinary antigen detection kit were S. pneumoniae culture-positive, including five who exhibited phagocytosis, indicating S. pneumoniae as a causative agent of infection, in Gram staining of sputum samples. These results suggest that the ODK0501 direct sputum detection kit is more clinically useful than the urinary antigen detection kit in adult patients with respiratory infections.

Effects of adiponectin on growth and differentiation of human keratinocytes--implication of impaired wound healing in diabetes

Impaired wound healing is one of the most common complications associated with diabetes. Adiponectin is an abundant circulating adipocyte-derived cytokine that has beneficial effects on disorders accompanying diabetes. Herein we report that adiponectin has a regulatory effect on the growth and differentiation of HaCaT human keratinocyte cells. Furthermore, adiponectin regulated the expression of TGFbeta isoforms in keratinocytes in a dose-dependent manner, which implies that adiponectin modulates other types of cells related to wound repair via secretion of growth factors from keratinocytes. Moreover, TUNEL assay results revealed that adiponectin enhances apoptosis of keratinocytes. Taken together, the present results indicate that adiponectin has suppressive effects on the formation of hyperkeratosis commonly seen in patients with diabetic foot and its application may be beneficial for developing treatment for that disorder.

Arthrobacter oryzae sp. nov. and Arthrobacter humicola sp. nov

Two novel bacterial strains were isolated from a paddy soil sample collected in Japan using GPM agar plates supplemented with superoxide dismutase and/or catalase. The strains were Gram-positive, catalase-positive and motile, with lysine as the peptidoglycan diagnostic diamino acid and acetyl as the peptidoglycan acyl type. The major menaquinone was MK-9(H(2)). Mycolic acids were not detected. The G+C content of the DNA was 66-68 mol%. On the basis of phenotypic analysis, 16S rRNA gene sequence comparisons and DNA-DNA hybridization data, it is proposed that these strains represent two novel species, Arthrobacter oryzae sp. nov. (type strain is KV-651(T)=NRRL B-24478(T)=NBRC 102055(T)) and Arthrobacter humicola sp. nov. (type strain is KV-653(T)=NRRL B-24479(T)=NBRC 102056(T)), respectively.

Microbacterium sediminicola sp. nov. and Microbacterium marinilacus sp. nov., isolated from marine environments

Two novel Microbacterium species are described on the basis of phenotypic, chemotaxonomic and genotypic studies. The two strains, designated YM10-847T and YM11-607T, were isolated from river sediment and unidentified hydroid, respectively, of a marine lake. The strains were Gram-positive, catalase-positive bacteria with l-ornithine as the diagnostic diamino acid of the peptidoglycan. The acyl type of the peptidoglycan was N-glycolyl. The major menaquinones were MK-10 and MK-11 for YM10-847T, and MK-11 and MK-12 for YM11-607T. Mycolic acids were not detected. The DNA G+C content of strains YM10-847T and YM11-607T was 67.8 and 71.6 mol%, respectively. Comparative 16S rRNA gene sequence analysis revealed that the two strains belong to the genus Microbacterium. DNA–DNA relatedness data showed that YM10-847T and YM11-607T are two novel species of this genus. On the basis of these results, strains YM10-847T and YM11-607T represent two novel species of the genus Microbacterium, for which the names Microbacterium sediminicola sp. nov. and Microbacterium marinilacus sp. nov. are proposed. The type strains are YM10-847T (=MBIC08264T=DSM 18905T) and YM11-607T (=MBIC07778T=DSM 18904T), respectively.

Humihabitans oryzae gen. nov., sp. nov

Strain KV-657T was isolated from a paddy field soil sample collected in Japan using GPM agar plates supplemented with catalase. The strain was a Gram-positive, aerobic organism that formed branching hyphae with ll-diaminopimelic acid as the diagnostic peptidoglycan diamino acid. The major menaquinone was MK-8(H4). Mycolic acids were not detected. The G+C content of the DNA was 70 mol%. 16S rRNA gene sequence analysis revealed that this strain is closely related to Intrasporangium calvum DSM 43043T, with a similarity of 97.6 %. Based on the morphological, biochemical and chemotaxonomic properties of this strain and phylogenetic analysis, it was concluded that this isolate represents a new genus and species in the family Intrasporangiaceae, for which the name Humihabitans oryzae gen. nov., sp. nov. is proposed. The type strain of Humihabitans oryzae is KV-657T (=NRRL B-24470T =NBRC 101802T).

Microbacterium terricolae sp. nov., isolated from soil in Japan

The taxonomic positions of two novel strains isolated from a soil sample collected in Japan using Glucose-Peptone-Meat extract (GPM) agar plates supplemented with superoxide dismutase or superoxide dismutase plus catalase were investigated based on the results of chemotaxonomic, phenotypic and genotypic characteristics. Strains were Gram-positive, catalase-positive, non-motile bacteria with L-ornithine as a diagnostic diamino acid of the peptidoglycan. The acyl type of the peptidoglycan was N-glycolyl. The major menaquinones were MK-12 and 13. Mycolic acids were not detected. The G+C content of the DNA was 70 mol%. Comparative 16S rRNA studies on the two isolated strains revealed that they belong to the genus Microbacterium. DNA-DNA relatedness data revealed that KV-448(T) and KV-769 are a new species of the genus Microbacterium. From these results, we propose that these bacteria should be classified in the genus Microbacterium as Microbacterium terricolae sp. nov. The type strain of Microbacterium terricolae is KV-448(T) (=NRRL B-24468(T), NBRC 101801(T)).

Taxonomy and Phylogenetic Analysis of Infectious Nocardia Strains Isolated from Clinical Samples

Following recent advances in medical technology, the increased number of immunocompromised patients such as those with organ transplants has led to an increase in opportunistic infections due to Nocardia. Although nocardiosis has been considered to be rare, recent reports indicate that the incidence of the infection is increasing. The Nocardia asteroides group is the principal source of infectious species, but the definition of species in Nocardia is problematic because species identification of N. asteroides has been based on mainly morphological and biochemical properties. Additionally, it was assumed that a clinical strain with properties that did not fully coincide with existing species was N. asteroides sensu lato. This caused problems in both clinical and taxonomical fields, and reclassification of N. asteroides sensu lato was necessary. Therefore, determination of the appropriate taxonomic position of N. asteroides sensu lato that is now classified as N. asteroides sensu stricto was conducted using a molecular phylogenetic method. From 1965 to 2001, twenty-two strains of N. asteroides sensu lato were isolated from clinical samples. The phylogenetic tree using 16S rDNA sequences and detailed biochemical characters on the 22 isolates was determined. Results revealed that nine strains should be reclassified into species other than N. asteroides sensu stricto, and we proposed nine new species of the genus Nocardia. In addition, we proposed eight other new species of the genus Nocardia from other samples; hence seventeen new species were proposed in total. We also reported the first infectious cases due to Nocardia beijingensis, Nocardia transvalensis and Nocardia pseudobrasiliensis in Japan.

Janibacter corallicola sp. nov., isolated from coral in Palau

A novel Janibacter species is described on the basis of phenotypic, chemotaxonomic and genotypic data. Two bacterial strains were isolated in Palau, which were both Gram-positive, catalase-positive bacteria with meso-diaminopimelic acid as the diagnostic diamino acid of the peptidoglycan. The major menaquinone was MK-8(H(4)). Mycolic acids were not detected. The G+C content of the DNA was 70-71 mol%. Comparative 16S rDNA studies of the two isolated strains revealed that they both belonged to the genus Janibacter. DNA-DNA relatedness data revealed that 04PA2-Co5-61(T) and 02PA-Ca-009 belong to the same species, a new species of the genus Janibacter. From these results, Janibacter corallicola sp. nov. is proposed, with the type strain 04PA2-Co5-61(T) (=MBIC 08265(T), DSM 18906(T)).

Microbacterium deminutum sp. nov., Microbacterium pumilum sp. nov. and Microbacterium aoyamense sp. nov

Three novel bacterial strains were isolated from a soil sample collected in Japan by culture on a GPM agar plate supplemented with superoxide dismutase and catalase. The strains were Gram-positive, catalase-positive, non-motile bacteria with L-ornithine as a diagnostic diamino acid of the peptidoglycan. The acyl type of the peptidoglycan was N-glycolyl. The major menaquinones were MK-12, 13 and 14. Mycolic acids were not detected. G+C contents of the DNA were in the range 69-71 mol%. Comparative 16S rRNA gene sequence analysis revealed that the isolates belonged to the genus Microbacterium and were closely related to Microbacterium terregens, Microbacterium aurum, Microbacterium koreense, Microbacterium schleiferi and Microbacterium lacticum. However, M. aurum, M. koreense and M. lacticum clearly differed from the isolated strains based on the presence of L-lysine as the cell-wall diamino acid and various other chemotaxonomic characteristics. Levels of DNA-DNA relatedness showed that the isolated strains represented three separate genomic species. Based on both phenotypic and genotypic data, the following novel species of the genus Microbacterium are proposed: Microbacterium deminutum sp. nov. (type strain KV-483(T)=NRRL B-24453(T)=NBRC 101278(T)), Microbacterium pumilum sp. nov. (type strain KV-488(T)=NRRL B-24452(T)=NBRC 101279(T)) and Microbacterium aoyamense sp. nov. (type strain KV-492(T)=NRRL B-24451(T)=NBRC 101280(T)).

Gordonia araii sp. nov. and Gordonia effusa sp. nov., isolated from patients in Japan

Two bacterial strains, IFM 10211T and IFM 10200T, were isolated from the sputum of two Japanese patients, and were subjected to a polyphasic taxonomic study. The two strains were found to have morphological, physiological and chemotaxonomic properties that were consistent with their assignment to the genus Gordonia, except for a few chemotaxonomic characteristics. Almost complete 16S rRNA gene sequences of the two strains were determined; the data showed that they are related distantly to Gordonia amarae, Gordonia hirsuta, Gordonia hydrophobica and Gordonia sihwensis, showing 16S rRNA gene sequence similarities to the type strains of these species of 96.2–97.9 %. DNA–DNA relatedness data coupled with the combination of genotypic and phenotypic data indicated that the two strains are representatives of two novel, separate species. The names proposed to accommodate these two strains are Gordonia araii sp. nov. (type strain IFM 10211T=DSM 44811T=NBRC 100433T=JCM 12131T) and Gordonia effusa sp. nov. (type strain IFM 10200T=DSM 44810T=NBRC 100432T=JCM 12130T).

Nocardia exalbida sp. nov., isolated from Japanese patients with nocardiosis

Two bacterial strains isolated from different hospitals in Japan were subjected to a polyphasic analysis. Strains IFM 0803T and IFM 10383 were found to have morphological, biochemical, physiological and chemotaxonomic properties consistent with their classification in the genus Nocardia. Strains IFM 0803T and IFM 10383 clustered with the type strain of Nocardia xishanensis, showing 16S rRNA gene sequence similarities of 98.6–98.9 % with this species. The novel strains could be distinguished from N. xishanensis by a range of phenotypic properties. Based on their phenotypic and phylogenetic characteristics, the two isolates are proposed as members of a novel species of the genus Nocardia, Nocardia exalbida sp. nov., with the type strain IFM 0803T (=NBRC 100660T=JCM 12667T=DSM 44883T).

First Clinical Isolates of Nocardia carnea, Nocardia elegans, Nocardia paucivorans, Nocardia puris and Nocardia takedensis in Japan

Five aerobic actinomycete strains isolated from patients in Japan were assigned provisionally to the genus Nocardia based on morphological and physiological characteristics. The five strains, IFM 10481, IFM 0668, IFM 0901, IFM 0583 and IFM 0342, were not classified into any Nocardia species reported as infectious agents in Japan. Therefore, they were studied further to determine their specific taxonomic positions. Detailed chemotaxonomic and physiologic characterization and 16S rDNA sequence data of the five strains showed that they belonged to respective species of Nocardia carnea, N. elegans, N. paucivorans, N. puris and N. takedensis. This is the first isolation report of these five Nocardia species from patients in Japan.

Oryzihumus leptocrescens gen. nov., sp. nov

Three novel strains were isolated from a soil sample collected in Japan using GPM agar plates supplemented with superoxide dismutase and/or catalase. The strains were Gram-positive, catalase-positive, irregular rod-shaped bacteria with meso-diaminopimelic acid as a peptidoglycan diagnostic diamino acid, and the acyl type of the peptidoglycan was acetyl. The major menaquinone was MK-8(H4). Mycolic acids were not detected. The G+C content of the DNA was 72–73 mol%. On the basis of morphological and chemotaxonomic properties and a phylogenetic analysis using 16S rRNA gene sequences, these strains were classified as a novel genus and species, Oryzihumus leptocrescens gen. nov., sp. nov., in the family Intrasporangiaceae of the order Actinomycetales. The type strain is KV-628T (=NRRL B-24347T=JCM 12835T=NBRC 100762T).

Gordonia otitidis sp. nov., isolated from a patient with external otitis

The taxonomic positions of two clinically isolated actinomycetes were established using a polyphasic approach. The two strains, IFM 10032T, isolated from ear discharge of a 28-year-old Japanese female patient with external otitis, and IFM 10148, isolated from pleural fluid of a 60-year-old Japanese male patient with bronchitis, possessed meso-diaminopimelic acid as the diagnostic amino acid, MK-9(H2) as the predominant menaquinone and mycolic acids ranging from 58 to 64 carbons. The 16S rRNA gene sequences of the two strains were most closely related to those of Gordonia aichiensis, Gordonia sputi and ‘Gordonia jacobaea’. Differences in several phenotypic characteristics together with genotypic distinctiveness distinguish strains IFM 10032T and IFM 10148 from these three species. DNA–DNA hybridization results and the combination of genotypic and phenotypic data showed that the two strains belong to a single species, and merit recognition of a novel species within the genus Gordonia. The name proposed for this taxon is Gordonia otitidis sp. nov.; the type strain is IFM 10032T (=DSM 44809T=JCM 12355T=NBRC 100426T).

Nocardia concava sp. nov., isolated from Japanese patients

Two actinomycete strains, IFM 0354T and IFM 0576, isolated from Japanese patients, were found to have morphological, biochemical and chemotaxonomic properties consistent with their classification in the genus Nocardia. The strains resembled Nocardia otitidiscaviarum and Nocardia uniformis in their phenotypic properties. Comparative 16S rRNA gene sequence analysis showed that the strains are closely related to Nocardia seriolae. DNA–DNA relatedness values and phenotypic differences from N. seriolae indicated that the strains belong to a novel species of Nocardia, for which the name Nocardia concava sp. nov. is proposed. The type strain is IFM 0354T (=NBRC 100430T=JCM 12351T=DSM 44804T).

Nocardia cyriacigeorgica is a significant pathogen responsible for nocardiosis in Japan and Thailand

Nocardia cyriacigeorgica is a recently described species. During routine diagnostic testing of 121 clinical isolates, we found that about one fourth of the strains from Japan (19 isolates) and Thailand (8 isolates), which were identified in our laboratories as N. asteroides, in fact belong to N. cyriacigeorgica. To our knowledge, this is the first report of infection due to N. cyriacigeorgica in Japan and Thailand, and the third report of infection anywhere in the world. Although N. cyriacigeorgica is usually differentiated from other Nocardia species by utilization of glucose and gluconate, we found that it can also be differentiated by a characteristic synergistic effect between imipenem (IPM) and tobramycin (TOB).

Nocardia shimofusensis sp. nov., isolated from soil, and Nocardia higoensis sp. nov., isolated from a patient with lung nocardiosis in Japan

Three actinomycete strains isolated from soils and one strain isolated from a patient with lung nocardiosis in 1999 and 2001 in Japan have been provisionally assigned to the genus Nocardia on the basis of morphological criteria. These isolates were further investigated to determine their specific taxonomic status. Detailed chemotaxonomic characterization and 16S rRNA gene sequence analysis of these isolates confirmed that they belong to the genus Nocardia. The 16S rRNA gene sequences of the four strains were most similar to that of Nocardia farcinica. However, the sequence similarity values between these four strains and N. farcinica were <98.9 %. These four strains were susceptible to 5-fluorouracil, and they have the ability to decompose urea, which is a very characteristic trait. Furthermore, DNA-DNA relatedness data revealed that IFM 10311(T), IFM 10312 and IFM 10313 comprise a single novel species of Nocardia, that IFM 10084(T) represents another novel species of Nocardia and that these two novel species could be distinguished from N. farcinica. The names Nocardia shimofusensis sp. nov. and Nocardia higoensis sp. nov. are proposed, with IFM 10311(T) (=NBRC 100134(T)=JCM 12122(T)=DSM 44733(T)) and IFM 10084(T) (=NBRC 100133(T)=JCM 12121(T)=DSM 44732(T)) as the respective type strains.

Nocardia araoensis sp. nov. and Nocardia pneumoniae sp. nov., isolated from patients in Japan

Two actinomycete strains isolated from two patients with lung nocardiosis between 1995 and 1997 in Japan were assigned to novel species of the genus Nocardia based on morphological and chemical criteria. Comparative 16S rRNA gene sequence analysis of the two strains revealed that they belong to the genus Nocardia and are most closely related to the species Nocardia beijingensis. Determination of DNA-DNA relatedness indicated that these strains could be assigned to two novel species. Based on their phenotypic and phylogenetic characters, two novel species of the genus Nocardia are proposed: Nocardia araoensis sp. nov. for IFM 0575(T) (=NBRC 100135(T)=JCM 12118(T)=DSM 44729(T)) and Nocardia pneumoniae sp. nov. for IFM 0784(T) (=NBRC 100136(T)=JCM 12119(T)=DSM 44730(T)).

Clinical isolates of Nocardia brasiliensis from Japan exhibit variable susceptibility to the antibiotic imipenem

Clinical isolates of Nocardia brasiliensis from Japan were classified into two groups based on their susceptibility to the carbapenem antibiotic, imipenem (IPM). Of 33 strains tested, 10 belonged to an IPM susceptible group, with MIC of from 0.25 to 2 microg/ml and a MIC(80) value of 1.5 microg/ml for this antibiotic. The remaining 23 strains belonged to an IPM resistant group with MIC and MIC(80) values of 8-16 microg/ml and >16 microg/ml, respectively. The type strain of N. brasiliensis belonged to this resistant group. Analysis of 16S rDNA genes sequences showed that the IPM susceptible group had characteristic single nucleotide substitutions at positions 103 (T), 381 (A), and 456 (A), in contrast to the IPM resistant group. This grouping, however, was not associated with their clinical manifestation.

Nocardia anaemiae sp. nov. isolated from an immunocompromised patient and the first isolation report of Nocardia vinacea from humans

Two actinomycete strains that were isolated from patients in Japan were assigned provisionally to the genus Nocardia based on their morphological characteristics. The two isolates were further studied to determine their specific taxonomic status. Detailed chemotaxonomic characterization and 16S rDNA sequence data for the strains showed that they are most similar to Nocardia vinacea. DNA-DNA hybridization experiments indicated that strain IFM 0344 should be identified as N. vinacea, and that strain IFM 0323T is classifiable as a new species. This report describes the first isolation of N. vinacea from clinical samples. A new species of the genus Nocardia is proposed based on their phenotypic and phylogenetic characteristics: Nocardia anaemiae for IFM 0323T (=NBRC 100462T=JCM 12396T=DSM 44821T).

Nocardia aobensis Sp. Nov., isolated from patients in Japan

Five clinical isolates, strains IFM 0137, 0372(T), 0496, 0556, and 0952, were provisionally assigned to the genus Nocardia based on morphological criteria. Nearly complete 16S rDNA sequences were determined for these strains. These data showed that they are most similar to that of Nocardia africana, Nocardia cerradoensis and Nocardia veterana. However, DNA-DNA relatedness data showed that the five strains were of a single species and were distinguishable from N. africana, N. cerradoensis and N. veterana. Therefore, these strains represent a new species within the genus Nocardia. The designation of these five strains is Nocardia aobensis sp. nov. The type strain is IFM 0372(T) (=NBRC 100429(T)=JCM 12352(T)=DSM 44805(T)).

Phosphatidylinositol 3-Kinase/Akt-Dependent and -Independent Protection Against Apoptosis in Normal Human Melanocytes

Normal human melanocytes require the synergistic action of several growth-promoting agents for their growth in serum-free medium. The ability of four representative growth promoting agents including insulin, 12-O-tetradecanoylphorbol-13-acetate (TPA), basic fibroblast growth factor (bFGF), and 3-isobutyl-1-methylxanthine (IBMX), (iTbI) to protect melanocytes against apoptosis was examined. Also, the involvement of phosphatidylinositol (PI) 3-kinase and Akt, one of the downstream targets of PI 3-kinase, in the survival signaling pathway was examined. The percentage of apoptotic cells was negligible when the cells were grown in the presence of iTbI. Deprivation of iTbI from the culture medium for 72 h caused approximately 30% of melanocytes to undergo apoptosis and this was suppressed to variable extents by the addition of one of the iTbI to the medium. Insulin and TPA protected against apoptosis almost completely, whereas bFGF and IBMX rescued melanocytes from apoptosis to a lesser extent. Wortmannin, an inhibitor of PI 3-kinase, potently inhibited the protective effect of insulin on melanocytes, whereas it did not block the ability of TPA, bFGF, or IBMX to rescue the cells from apoptosis. Furthermore, apoptosis of melanocytes induced by deprivation of iTbI was prevented almost completely by infection with an adenovirus vector encoding a constitutively active mutant of either PI 3-kinase or Akt. These results indicate that melanocytes can operate both PI 3-kinase/Akt-dependent and -independent mechanisms for protection against apoptosis and that activation of the PI 3-kinase/Akt pathway is sufficient for protection against apoptosis induced by deprivation of growth-promoting agents.

Nocardia testaceus sp. nov. and Nocardia senatus sp. nov., isolated from patients in Japan

Two actinomycete strains isolated from sputum between 1999 and 2001 in Japan were provisionally assigned to the genus Nocardia based on morphological criteria. These isolates were further studied in order to determine their specific taxonomic status. Detailed chemotaxonomic characterization and 16S rDNA gene sequence analysis of these isolates also confirmed that they belong to the genus Nocardia. The 16S rDNA sequence data of the two strains showed that they are most similar to that of Nocardia carnea and Nocardia flavorosea. However, DNA-DNA relatedness data showed that the two strains could be distinguished from N. carnea and N. flavorosea and therefore represented two new species within the genus Nocardia. The designation of the two isolated strains are Nocardia testaceus for IFM 0937(T) (=JCM 12235(T), DSM 44765(T)) and Nocardia senatus for IFM 10088(T) (=JCM 12236(T), DSM 44766(T)).

Nocardia arthritidis sp. nov., a new pathogen isolated from a patient with rheumatoid arthritis in Japan

Two different bacterial strains with different drug susceptibilities were isolated from the sputum and an inflammatory discharge from a swelling in the left thigh of a patient with rheumatoid arthritis. Both bacterial strains were provisionally assigned to the genus Nocardia on the basis of their morphological and chemotaxonomic characteristics and were further studied in order to establish their taxonomic status. One strain (IFM 10034) was identified as Nocardia farcinica on the basis of its physiological characteristics. The other strain, which was designated Nocardia sp. strain IFM 10035(T), revealed a unique pattern of phenotypic properties that distinguished it from other representatives of established Nocardia species. Comparative 16S rRNA gene sequence studies of Nocardia sp. strain IFM 10035(T) also showed that the bacterium was closely related to the species Nocardia beijingensis. Determination of DNA-DNA relatedness, however, indicated that Nocardia sp. strain IFM 10035(T) could be delineated from N. beijingensis. The genotypic and phenotypic data combined indicated that the bacterium merits description as a new Nocardia species. The name proposed for the new species is Nocardia arthritidis sp. nov., the type strain being IFM 10035(T) (NBRC 100137(T), JCM 12120(T), DSM44731(T)). The present study suggests that Nocardia infections can be caused by multiple species of the bacterium.

Nocardia inohanensis sp. nov., Nocardia yamanashiensis sp. nov. and Nocardia niigatensis sp. nov., isolated from clinical specimens

Comparative 16S rDNA studies on six strains of actinomycete isolated from clinical specimens revealed that they belong to the genus Nocardia and are closely related to Nocardia seriolae, Nocardia otitidiscaviarum, Nocardia uniformis, Nocardia pseudobrasiliensis and Nocardia crassostreae. However, the novel organisms consistently formed a clade distinct from that of the five latter species. Determination of DNA-DNA relatedness indicated that these strains could be classified under three novel species. Based on their phenotypic and phylogenetic characters, three novel species of the genus Nocardia are established: Nocardia inohanensis sp. nov. for IFM 0092(T) (=NBRC 100128(T)=JCM 11891(T)=DSM 44667(T)), Nocardia yamanashiensis sp. nov. for IFM 0265(T) (=NBRC 100130(T)=JCM 11893(T)=DSM 44669(T)) and Nocardia niigatensis sp. nov. for IFM 0330(T) (=NBRC 100131(T)=JCM 11894(T)=DSM 44670(T)), IFM 0260, IFM 0636 and IFM 0833.

Nocardia beijingensis, is a pathogenic bacterium to humans: the first infectious cases in Thailand and Japan

Nocardia beijingensis, a recently established new species, is an isolate from soil in China. During our taxonomic studies on 450 nocardial clinical isolates in Thailand and Japan, 17 strains from Thailand and 1 strain from Japan were found to have a similar physiological characteristic to those of N. beijingensis, such as a drug susceptibility pattern to three antimicrobial agents. Our phylogenetic studies on these 18 strains by 16S rRNA gene sequence analysis confirmed that these strains belong to N. beijingensis species. Phylogenetically, these newly isolated N. beijingensis strains were found to be classified into two distinct clades: one is a Japanese clade and other is a Chinese clade, including a reference strain and 17 Thai strains. This is the first report of human infection due to N. beijingensis strains, and we propose that the bacterium be categorized as an opportunistic infectious group regardless of its original isolation from soil.

Down-regulation of melanogenesis by phospholipase D2 through ubiquitin proteasome-mediated degradation of tyrosinase

The involvement of phospholipase D (PLD) in the regulation of melanogenesis was examined. Treatment of B16 mouse melanoma cells with 12-O-tetradecanoylphorbol-13-acetate (TPA) resulted in the activation of PLD and a decrease in melanin content. 1-Butanol, but not 2-butanol, completely blocked the TPA-induced inhibition of melanogenesis, suggesting the involvement of PLD in this event. Reverse transcription-PCR and immunoblot analyses revealed the existence of both PLD isozymes, PLD1 and PLD2, in B16 cells. When PLD1 or PLD2 was introduced into those cells by an adenoviral gene-transfer technique, both PLD1 and PLD2 were activated by TPA. When PLD1 and PLD2 were overexpressed, PLD2 potently caused a decrease in melanin content, whereas the effect of PLD1 expression on melanin content was minimal. Over-expression of PLD2 itself did not affect protein kinase C activity, as assessed by the intracellular distribution and levels of expression of each isoform expressed in B16 cells. The effects of TPA on the down-regulation of basal or alpha-melanocyte-stimulating hormone-enhanced melanogenesis were almost completely blocked by expressing a lipase activity-negative mutant, LN-PLD2, but not by LN-PLD1. Further, the PLD2-induced decrease in melanin content was accompanied by a decrease in the amount and activity of tyrosinase, a key enzyme in melanogenesis, whereas the mRNA level of tyrosinase was unchanged by the over-expression of PLD2. Moreover, treatment with proteasome inhibitors completely blocked the PLD2-induced down-regulation of melanogenesis. Taken together, the present results indicate that the TPA-induced down-regulation of melanogenesis is mediated by PLD2 but not by PLD1 through the ubiquitin proteasome-mediated degradation of tyrosinase. This suggests that PLD2 may play an important role in regulating pigmentation in vivo.

Nocardia asiatica sp. nov., isolated from patients with nocardiosis in Japan and clinical specimens from Thailand

Five strains isolated from two patients with nocardiosis in Japan and three clinical samples from Thailand were found to have morphological, biochemical and chemotaxonomic properties consistent with their classification in the genus Nocardia. DNA-DNA hybridization, coupled with sequence analysis of 16S rDNA, indicated that these strains belong to a novel species of the genus Nocardia, named Nocardia asiatica sp. nov. because the isolation sites were in Asian countries; the type strain is IFM 0245T (=NBRC 100129T=JCM 11892T=DSM 44668T).

First Isolates of Nocardia abscessus from Humans and Soil in Japan

Nocardia abscessus, a recently established species, was isolated from patients during 2000. In the course of our taxonomic studies on 121 clinical Nocardia isolates in Japan 5 strains isolated from patients plus one strain isolated from soil in Japan, were found to have similar physiological characteristics to those of N. abscessus. Phylogenetic studies using 16S rRNA gene sequence analysis confirmed that these strains belong to N. abscessus. This is the first isolation report of N. abscessus from soil as well as from clinical samples in Japan.

Ventromedial hypothalamus lesions induce jejunal epithelial cell hyperplasia through an increase in gene expression of cyclooxygenase

BACKGROUND

We demonstrated that ventromedial hypothalamus (VMH) lesions facilitate DNA synthesis, which reflects cell proliferation in abdominal organs, including the liver, pancreas, stomach, small intestine and large intestine, all of which are amply innervated by the vagal nerve.

OBJECTIVE

To investigate which area DNA synthesis facilitates and what factors contribute to cell proliferation in the small intestine in VMH-lesioned rats.

DESIGN

At 7 days after VMH lesions or sham operations, a segment of rat jejunum was taken for histological examination. A part of the jejunum was also removed from VMH-lesioned and sham-operated rats after 3 days and examined for 5-bromo-2'-deoxyuridine (BrdU) incorporation. At 6, 12 and 24 h after VMH lesions, the proximal intestine was removed from individual rats, from the pylorus to the mid-jejunum. Total RNA was extracted from these tissues of each rat, and the levels of epidermal growth factor (EGF) and transforming growth factor (TGF)-alpha mRNA were determined using reverse-transcription polymerase chain reaction. Cyclooxygenase (COX)-1 and -2 mRNA levels were determined using Northern blotting.

RESULTS

: Jejunal villi in VMH-lesioned rats were markedly enlarged compared to those of sham-operated rats and jejunal crypts in VMH-lesioned rats more markedly incorporated BrdU. Northern blot analysis revealed an increase in COX-1 mRNA after 6, 12 and 24 h in the jejunum of VMH-lesioned rats. COX-2 mRNA was decreased 6 and 12 h after VMH lesioning; however, it was significantly increased 24 h after VMH lesions in comparison to sham-operated rats. The levels of EGF and TGF-alpha mRNA were unchanged in VMH lesioned rats.

CONCLUSION

VMH lesions induced enlargement of jejunal villi and increased the gene expression of COX-1 in the small intestine. Prostaglandins, probably E(2), induced by COX-1 may be one candidate factor responsible for the cell proliferation of the small intestinal epithelium in these rats.

First human case of nocardiosis caused by Nocardia pseudobrasiliensis in Japan

Nocardia sp. IFM 0896, an actinomycete with biochemical characteristics that differed from Nocardia brasiliensis, was isolated from a 71-year-old Japanese man with a history of tuberculosis and cancer. Although the isolate was tentatively identified as N. brasiliensis, the morphological and physiological characteristics of strain IFM 0896 were different from those of N. brasiliensis IFM 0236T. The results of 16S rRNA gene sequence phylogenies and PCR-RFLP analysis of a heat shock protein revealed that Nocardia sp. IFM 0896 belongs to the species N. pseudobrasiliensis. This is the first clinical isolation report of N. pseudobrasiliensis in Japan.

Nocardial Infections in Japan from 1992 to 2001, Including the First Report of Infection by Nocardia transvalensis

In the period from 1992 to 2001, 303 cases of nocardioses were diagnosed in Japan, with the corresponding etiological agents isolated and characterized. Taxonomic analyses of these 303 strains showed that most nocardial infections were caused by members of the Nocardia asteroides group (72.3%). Speciation showed that 72 strains were N. asteroides, 31 strains were N. cyriacigeorgica, 2 strains were N. beijingensis, 81 strains were N. farcinica, and 33 strains were N. nova. Sixty-six strains of N. brasiliensis were the next most prevalent species of the total Nocardia isolates, followed by 14 strains of N. otitidiscaviarum. Infections by N. transvalensis (3 strains) and N. pseudobrasiliensis (1 strain) were also confirmed. The infections due to N. transvalensis, N. cyriacigeorgica, and N. beijingensis were the first reported in Japan. The most common factor that predisposed individuals to nocardial infection in Japan was therapy by immunosuppressive agents (22.4%), including SLE therapy (3.6%), followed by cancer (6.6%), diabetes (3.6%) and AIDS (2.0%). Nocardial infections occurred more commonly in the elderly, with most of the patients between the ages of 61 and 80 years of age. No significant difference regarding infectivity levels between the sexes was observed.

Rapid detection of human fecal Eubacterium species and related genera by nested PCR method

PCR procedures based on 16S rDNA gene sequence specific for seven Eubacterium spp. and Eggerthella lenta that predominate in the human intestinal tract were developed, and used for direct detection of these species in seven human feces samples. Three species of Eggerthella lenta, Eubacterium rectale, and Eubacterium eligens were detected from seven fecal samples. Eubacterium biforme was detected from six samples. It was reported that E. rectale, E. eligens, and E. biforme were difficult to detect by traditional culture method, but the nested PCR method is available for the detection of these species. This result shows that the nested PCR method utilizing a universal primer pair, followed by amplification with species-specific primers, would allow rapid detection of Eubacterium species in human feces.

Enhancement of diphtheria toxin-induced apoptosis in Vero cells by combination treatment with brefeldin A and okadaic acid

In the present study, we compared the abilities of ricin and diphtheria toxin to induce apoptosis in Vero cells. The cytolysis and DNA fragmentation by ricin paralleled its protein synthesis inhibitory activity. However, unlike ricin, diphtheria toxin could induce neither cytolysis nor DNA fragmentation in Vero cells up to very high concentration, in spite of the fact that Vero cells were even more sensitive to protein synthesis inhibition by diphtheria toxin than ricin. Interestingly, coexistence of brefeldin A (BFA) and okadaic acid (OA) significantly enhanced diphtheria toxin-mediated cytolysis and DNA fragmentation without affecting the activity of protein synthesis inhibition. Ammonium chloride almost completely abolished the ability of diphtheria toxin to induce apoptosis in the presence of BFA and OA as well as the protein synthesis inhibitory activity. The mutant CRM 197, which does not catalyze the ADP ribosylation of elongation factor-2 (EF-2), failed to induce apoptosis in Vero cells even in the presence of BFA and OA. Thus, translocation of diphtheria toxin into the cytosol and subsequent enzymatic inactivation of EF-2 may be necessary steps to induce apoptosis. Taken together our results suggest that protein synthesis inhibition by toxins is not sufficient to induce apoptosis, and underlying mechanisms of apoptosis induction may be distinct between ricin and diphtheria toxin. Since a morphological change in the Golgi complex was observed in Vero cells treated with BFA and OA, modulation of the Golgi complex by these reagents may be partly responsible for enhanced apoptosis induction by diphtheria toxin.

Impaired reductive regeneration of ascorbic acid in the Goto-Kakizaki diabetic rat

Ascorbic acid (AA) is a naturally occurring major antioxidant that is essential for the scavenging of toxic free radicals in both plasma and tissues. AA levels in plasma and tissues have been reported to be significantly lower than normal in diabetic animals and humans, and might contribute to the complications found at the late stages of diabetes. In this study, plasma and hepatic AA levels and AA regeneration were studied in the Goto-Kakizaki diabetic rat (GK rat) to elucidate the mechanism of decreasing plasma and hepatic AA levels in diabetes. AA concentrations in the plasma and liver were significantly lower in GK than in control rats. AA levels in primary cultured hepatocytes derived from GK rats were lower than those derived from control Wistar rats with or without dehydroascorbic acid (DHA) in the medium. Among various enzyme activities that reduce DHA to AA, the NADPH-dependent regeneration of AA in the liver was significantly suppressed in GK rats. Northern blot analysis revealed that only the expression of 3-alpha-hydroxysteroid dehydrogenase (AKR) was significantly suppressed in these rats. These results suggest that decreased AA-regenerating activity, probably through decreased expression of AKR, contributes to the decreased AA levels and increased oxidative stress in GK rats.

Phylogenic and phenotypic characterization of some Eubacterium-like isolates from human feces: description of Solobacterium moorei Gen. Nov., Sp. Nov

Three isolated strains from human feces were characterized by biochemical tests and 16S rDNA analysis. Phylogenetic analysis revealed that these isolated strains were members of the Clostridium subphylum of gram-positive bacteria. The phenotypic characters resembled those of the genus Eubacterium, but these strains were shown to be phylogenetically distant from the type species of the genus, Eubacterium limosum. The strains showed a specific phylogenetic association with Holdemania filiformis and Erysipelothrix rhusiopathiae. Based on a 16S rDNA sequence divergence of greater than 12% with H. filiformis and E. rhusiopathiae, a new genus, Solobacterium, is proposed for three strains, with one species, Solobacterium moorei. The type strain of Solobacterium moorei is JCM 10645T.

Emendation of genus Collinsella and proposal of Collinsella stercoris sp. nov. and Collinsella intestinalis sp. nov

Collinsella aerofaciens-like strains isolated from human faeces were characterized by biochemical tests, cell wall murein analysis and 16S rDNA analysis. The results indicated that these strains are phylogenetically a member of the family Coriobacteriaceae and close to the genus Collinsella. Their phenotypic characters resembled those of Collinsella aerofaciens. Determination of DNA-DNA relatedness showed that these strains could be divided into two groups (groups 1 and 2). Collinsella aerofaciens and both new groups have A4-type cell wall murein. Based on their phenotypic and phylogenetic characters, two new species of the genus Collinsella are proposed for the isolated strains: Collinsella stercoris for group 1 and Collinsella intestinalis for group 2. Species-specific PCR primer sets for these two species were also constructed. Using these primer sets, Collinsella stercoris and Collinsella intestinalis can be identified easily and rapidly.

Catenibacterium mitsuokai gen. nov., sp. nov., a gram-positive anaerobic bacterium isolated from human faeces

Six strains of Eubacterium-like strains from human faeces were characterized by biochemical tests and analysis of cell wall peptidoglycan type and 16S rRNA. They were members of the Clostridium subphylum and have a specific phylogenetic association with Lactobacillus catenaformis and Lactobacillus vitulinus. These organisms resembled L. vitulinus in possessing the same A1gamma type of murein, but they showed different fermentation end-products. On the basis of a 16S rDNA sequence divergence of greater than 8% from L. vitulinus as well as phenotypic characteristics, a new genus, Catenibacterium, with one species (Catenibacterium mitsuokai), is proposed for six strains. The type strain of C. mitsuokai is JCM 10609T.

Coprobacillus catenaformis gen. nov., sp. nov., a new genus and species isolated from human feces

Three strains of Eubacterium-like isolates from human feces were characterized by biochemical tests and 16S rDNA analysis. The phenotypic characteristics of the three strains resembled those of the genus Collinsella transferred from the genus Eubacterium recently. However, Eubacterium-like strains were phylogenetically members of the Clostridium subphylum of gram-positive bacteria, and these showed a specific phylogenetic association with Clostridium ramosum and C. spiroforme. C. ramosum and C. spiroforme are gram-positive, anaerobic, spore-forming bacteria that belong to the genus Clostridium, and the G + C contents are 26.0 and 27.4 mol%, respectively. However, the three Eubacterium-like strains had G + C contents of 32.1 to 33.1 mol% and were non-spore-forming rods. Based on phenotypic characteristics, we can differentiate these species, and furthermore, a 16S rDNA sequence divergence of greater than 9% with a new related genus, Coprobacillus, is proposed for the three strains, with one species, Coprobacillus catenaformis. The type strain of C. catenaformis is JCM 10604T.

Rapid identification and quantification of Collinsella aerofaciens using PCR

The number and incidence of Collinsella aerofaciens in the human intestine are the highest among Gram-positive non-spore-forming bacilli. Identification of this species is very difficult and requires considerable time. A PCR-based identification system using C. aerofaciens-specific primers is described. Using this PCR method, we identified 181 C. aerofaciens-like species isolated from human feces. These 181 strains were identified using the traditional method in past studies. Results of both methods matched. The direct detection method was performed using human feces samples from seven adults. Nested PCR was applied directly to the samples and all seven samples were positive. Quantification studies were performed using LightCycler¿trade mark omitted¿. The assay uses a double-stranded DNA dye to continuously monitor product formation and in a short time is able to quantify samples to 5 log units in concentration.

Phylogenetic evidence for the transfer of Eubacterium lentum to the genus Eggerthella as Eggerthella lenta gen. nov., comb. nov

Eubacterium lentum has unique phenotypic characters within the genus Eubacterium. The 16S rRNA sequence of Eubacterium lentum was determined and its phylogenetic position was defined. This micro-organism is a member of the genus Eubacterium but it is not closely related to Eubacterium limosum, the type species of the genus Eubacterium, and is nearer to Collinsella aerofaciens and Coriobacterium glomerans. A PCR-based identification system using species-specific primers designed on the basis of DNA sequences encoding the 16S rRNA of strains of Eubacterium lentum, Collinsella aerofaciens and Coriobacterium glomerans is described. A species-specific primer set can distinguish Eubacterium lentum from Eubacterium limosum or closely related species including Collinsella aerofaciens, Coriobacterium glomerans and Atopobium species. This species-specific PCR method can be used to identify Eubacterium lentum-like species isolated from human faeces. On the basis of the 16S rRNA sequence divergence from Collinsella aerofaciens and Coriobacterium glomerans and the presence of unique phenotypic characters, a new genus, Eggerthella gen. nov., is proposed for Eubacterium lentum, with one species, Eggerthella lenta comb. nov. The type strain of Eggerthella lenta is JCM 9979T.

Phylogenic and phenotypic evidence for the transfer of Eubacterium fossor to the genus Atopobium as Atopobium fossor comb. nov

The 16S rRNA primary structure of Eubacterium fossor was determined by sequencing in vitro amplified rDNA. Sequence comparisons indicated that E. fossor has a specific phylogenetic association with the Atopobium species and is far from E. limosum, the type species of the genus Eubacterium. Phenotypic characters of E. fossor resemble those of the genus Atopobium. Therefore, we propose that E. fossor should be transferred to the genus Atopobium as Atopobium fossor comb. nov.

Phylogenetic and phenotypic evidence for the transfer of Eubacterium aerofaciens to the genus Collinsella as Collinsella aerofaciens gen. nov., comb. nov

Three strains of Eubacterium aerofacien, JCM 10188T, JCM 7790 and JCM 7791, and 178 freshly isolated strains of the Eubacterium aerofaciens group from human faeces were characterized by biochemical tests, cell wall peptidoglycan type and 16S rRNA analysis. The Eubacterium aerofaciens group was divided into four groups by fermentation patterns of sucrose and cellobiose, and were further divided into 16 sub-groups by fermentation patterns of aesculin, salicin and amygdalin. All of the strains of the Eubacterium aerofaciens group were shown to be phylogenetically distantly related to Eubacterium limosum, which is the type species of genus Eubacterium. Eubacterium aerofaciens was shown to have a specific phylogenetic association with Coriobacterium glomerans. All the strains belonging to Eubacterium aerofaciens resembled Coriobacterium glomerans in possessing a high G + C content (60 mol%). Cell wall analysis, however, revealed the presence of different A4 beta (L-Ala)-D-Glu-L-Orn-L-Asp peptidoglycan types. Based on a 16S rRNA sequence divergence of greater than 9% with Coriobacterium glomerans and the presence of a unique peptidoglycan type, a new genus, Collinsella, is proposed for Eubacterium aerofaciens, with one species, Collinsella aerofaciens. The type strain of Collinsella aerofaciens is JCM 10188T.