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M Onuki

Publications and source records attributed to M Onuki.

At least 19 recordsLinked to original sources
PubMed2006

Isolation, characterization of bacteriophages specific to Microlunatus phosphovorus and their application for rapid host detection.

AIMS: To isolate and characterize lytic-bacteriophages specific to Microlunatus phosphovorus, and prepare fluorescently labelled phages (FLPs) for the rapid detection of the host bacterium in activated sludge. METHODS AND RESULTS: Isolation of bacteriophages lytic to M. phosphovorus was attempted by applying supernatants of activated sludge processes on the lawn of M. phosphovorus JCM9379 for plaque formation. Thirteen bacteriophage isolates were obtained. The restriction fragment length polymorphism analysis distinguished them into two different bacteriophages designated as phiMP1 and phiMP2. They were found to possess double-stranded DNA and host specificity. Morphological observations were done by electron microscopy. The bacteriophage particles stained by SYBR Green I was shown to be applicable to detect their host bacterial cells mixed with activated sludge. CONCLUSIONS: Two M. phosphovorus-specific bacteriophages were isolated and classified as Siphoviridae. FLPs of them were prepared, and successfully applied to detect the host bacterium added into the activated sludge. SIGNIFICANCE AND IMPACT OF THE STUDY: At least some of bacteria in activated sludge are susceptible to their related bacteriophages. Bacteriophages lytic to activated sludge bacteria could be affecting the bacterial population in activated sludge. The FLPs could be used for the easy-rapid detection of their host bacterium in activated sludge.

Bacteriolysis↗
PubMed2006

Examining substrate uptake patterns of Rhodocyclus-related PAO in full-scale EBPR plants by using the MAR-FISH technique.

While recognised as the important population responsible for enhanced biological phosphorus removal (EBPR), detailed knowledge on the physiology of Rhodocyclus-related polyphosphate accumulating organisms (PAO) has yet to be grasped. The objective of this study was to examine the in situ substrate uptake patterns of Rhodocyclus-related PAO present in full-scale EBPR plants by the combined technique of microautoradiography-fluorescent in situ hybridization (MAR-FISH). The presence of these PAO in the four investigated plants was confirmed by FISH and they constituted 17%, 9%, 8%, and 7% of the sludge community. By using MAR-FISH technique, Rhodocyclus-related PAO in all the plants demonstrated similar anaerobic substrate uptake patterns. They were capable of assimilating acetate, aspartate and glutamate under anaerobic condition but they showed negative uptake with palmitate. A significant fraction of the MAR-positive cells assimilated acetate, aspartate or glutamate was found to be Rhodocyclus-related PAO. Dual staining with DAPI and FISH showed that these PAO also accumulated polyphosphate aerobically with aspartate and glutamate as carbon source. The ability of assimilating amino acids besides acetate strongly indicates the versatile physiology of Rhodocyclus-related PAO, which could benefit them to achieve predominance in EBPR activated sludge.

Environmental Restoration and Remediation↗
PubMed2006

Microbial community of biological phosphorus removal process fed with municipal wastewater under different electron acceptor conditions.

The microbial community in a biological phosphorus removal process under different electron acceptor conditions was estimated by polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) assay and principal-component analysis (PCA). For this purpose, a lab-scale sequencing batch reactor (SBR) fed with municipal wastewater was operated under anaerobic-aerobic, anaerobic-anoxic-aerobic and anaerobic-anoxic conditions. The results of PCR-DGGE targeting the 16S rRNA gene indicated a significant shift in the microbial community with electron acceptor conditions. From the 16S rRNA-based PCA, the microbial shift implies that little oxygen supply caused the deterioration of aerobic bacteria, including aerobic polyphosphate-accumulating organisms (PAOs). Moreover, it also reflects the existence of nitrate-utilizing denitrifiers. On the other hand, although the band patterns of DGGE targeting a functional gene of denitrification (nirS) also showed the microbial shift, the result of PCA differed from that of 16S rRNA-based analysis. There is no conclusive proof that the bacteria represented as the dominant bands detected in the present study are denitrifying-PAOs so far, it should be worthwhile to identify the detected bacteria and to examine their traits as new denitrifying-PAO candidates.

Bacteria↗
PubMed2006

Influence of flocculation and settling properties of activated sludge in relation to secondary settler performance.

Floc characteristics were studied at a full scale activated sludge treatment plant with a unique process solution incorporating pre-denitrification with post-nitrification in nitrifying trickling filters. Since greater nitrogen removal is achieved when more secondary settled wastewater is recirculated to the trickling filters, the secondary settlers are always operated close to their maximal capacity. The flocculation and settling properties are therefore crucial and have an effect on the overall plant performance. Since the plant is operated at a short sludge age, these properties change quickly, resulting in variable maximal secondary settler capacity. The dynamics in floc structure and microbial community composition were studied and correlated to the secondary settler performance. Fluorescence in situ hybridisation was used to investigate the microbial community structure and their spatial distribution. The floc structure could to some extent be related to the flocculation and settling properties of the sludge. Even small differences had an influence suggesting that colloidal properties also play a significant role in determining the floc properties. No correlation between microbial community composition and settling properties could be established with the group-specific probes investigated.

Environmental Restoration and Remediation↗
PubMed2002

Analysis of microbial community that performs enhanced biological phosphorus removal in activated sludge fed with acetate.

Enhanced biological phosphorus removal (EBPR) activated sludge was operated in a laboratory-scale sequencing batch reactor (SBR) fed with acetate as the sole carbon source. The microbial community of the sludge was analyzed using the polymerase chain reaction (PCR)-denaturing gradient gel electrophoresis (DGGE) method for about 2 months of start-up period. As a result, the number of major bands decreased during the enrichment, indicating that the microbial community structure was getting simpler. Since the phosphate removal activity was maintained at a high level, the bacteria which still remained at the end can be considered as the important bacteria playing key roles in the present EBPR sludge, maybe polyphosphate accumulating organisms (PAOs). The dominant band in the last sample on the DGGE gel was excised and the DNA recovered from it was sequenced. The sequence was closely related to one of the putative PAOs group which Crocetti et al. (2000) and Hesselmann et al. (1999) have proposed. This PAOs group is closely related to the Rhodocyclus group (b-Proteobacteria). The fluorescence in situ hybridization (FISH) method with the probe specific for this PAOs group and the DAPI staining at a phosphate-probing concentration indirectly showed that these Rhodocyclus related bacteria really accumulated polyphosphate.

Acetates↗
PubMed2002

Density separation and molecular methods to characterize enhanced biological phosphorus removal system populations.

A novel approach to the identification of microorganisms that accumulate high density microbial storage products based on density separation, denaturing gradient gel electrophoresis (DGGE), and DNA sequencing was developed and applied to bench and pilot scale enhanced biological phosphorus removal (EBPR) systems. Polyphosphate (PP), glycogen, and polyhydroxyalkanoates (PHAs), are all of higher density than a typical bacterial cell. PP-accumulating organisms (PAOs), the organisms responsible for EBPR, accumulate all three of these storage products. Density separation in a homogenous solution of Percoll produced a high-density biomass fraction with a relatively high concentration of PAOs, as determined by Neisser staining. DNA was extracted from these fractions, amplified, and separated by DGGE. DGGE profiles demonstrated some bacterial strains were present at a greater concentration in the high density fractions than in low density fractions. These strains were considered PAO candidates. 5 of 12 PAO candidates from high density fractions were gamma Proteobacteria and only 1 was a beta Proteobacterium. 2 PAO candidates were most similar to recently identified gamma Proteobacteria sequences obtained by DGGE analysis of a deteriorated benchtop EBPR system.

Biomass↗
PubMed2001

Granulocyte macrophage colony-stimulating factor: a new putative therapeutic target in multiple sclerosis.

Experimental autoimmune encephalomyelitis (EAE), a model for multiple sclerosis, can be induced by immunization with a number of myelin antigens. In particular, myelin oligodendrocyte glycoprotein, a central nervous system (CNS)-specific antigen expressed on the myelin surface, is able to induce a paralytic MS-like disease with extensive CNS inflammation and demyelination in several strains of animals. Although not well understood, the egress of immune cells into the CNS in EAE is governed by a complex interplay between pro and antiinflammatory cytokines and chemokines. The hematopoietic growth factor, granulocyte macrophage colony-stimulating factor (GM-CSF), is considered to play a central role in maintaining chronic inflammation. The present study was designed to investigate the previously unexplored role of GM-CSF in autoimmune-mediated demyelination. GM-CSF(-/)- mice are resistant to EAE, display decreased antigen-specific proliferation of splenocytes, and fail to sustain immune cell infiltrates in the CNS, thus revealing key activities for GM-CSF in the development of inflammatory demyelinating lesions and control of migration and/or proliferation of leukocytes within the CNS. These results hold implications for the pathogenesis of inflammatory and demyelinating diseases and may provide the basis for more effective therapies for inflammatory diseases, and more specifically for multiple sclerosis.

Animals↗
PubMed2001

Axonal degeneration is an early pathological feature in autoimmune-mediated demyelination in mice.

Multiple sclerosis (MS) is an inflammatory disorder of the central nervous system (CNS), characterised by focal destruction of myelin. Although it is evident that the immune system contributes to tissue destruction in MS, it is still unclear as to whether this immune response is a cause or a consequence of the disease process. In addition, there is debate over the contribution of axonal damage to clinical progression. We have described a murine model of relapsing-remitting MS (RR-MS), the most common form of the disease, following immunisation with the myelin component, myelin oligodendrocyte glycoprotein (MOG). We showed that a single injection of a MOG peptide (MOG(35-55)) in NOD/Lt mice induces a paralytic relapsing disease with extensive plaque-like demyelination. This model also mimics many of the immunological features associated with RR-MS. To investigate the relationship between clinical episodes, inflammation, and demyelination/remyelination, we analysed lesions during each attack and remission over the course of the disease, using histological, immunocytochemical, and electron microscopy (EM) techniques. We show that morphological features of lesions in our model resemble those observed in MS. Indeed, severe inflammation and demyelination coincide with the peak of clinical episodes while remissions are characterised by quiescent plaques. Furthermore, axonal damage is evident from the earliest stage of the disease and increases in severity with subsequent relapses. These data establish that in the model of MS-like disease, the peak of clinical episodes coincides with severe inflammation and demyelination and that axonal pathology correlates with clinical progression.

Animals↗
PubMed2001

[A case of recurrent breast cancer successfully treated with docetaxel].

A 50-year-old female underwent mastectomy for left breast cancer in June, 1991. She received tamoxifen for 36 months and tegafur for 30 months as adjuvant therapy. In November 1997, liver, lung and para-aortic lymph node recurrences were found, and we treated her six times with docetaxel 60 mg. After the chemotherapy, a complete response (CR) of all metastatic lesions was achieved and her serum CA15-3 level was decreased. Adverse reactions were grade 4 neutropenia, grade 2 alopecia, fever, and grade 1 edema. She received medroxyprogesterone acetate after the chemotherapy and has been well without re-growth of any metastases for over eight months.

Antineoplastic Agents, Phytogenic↗
PubMed2000

Recurrent follicular and lichenoid papules of sarcoidosis.

We describe a 62-year-old Japanese woman who exhibited recurrent follicular lichenoid lesions of sarcoidosis. The skin lesions appeared all over the surface of the body without any other organ involvement, and spontaneously regressed within 1 year. Two years later, the lesions recurred on the trunk, especially in the intertriginous areas such as the submammary areas and in fatty folds of the abdomen, and on the thighs and upper arms, with the appearance of uveitis of the right eye. Histological examinations showed that small epithelioid cell granulomas were localized in the perifollicular areas. The present case was characterized by a unique distribution of follicular lichenoid eruptions, which are rare manifestations of sarcoidosis and recurrence of the lesions.

Biopsy↗
PubMed1997

[Depression during interferon therapy in chronic hepatitis C patients--a prospective study].

The number of patients treated with interferon (IFN) has increased markedly in Japan since 1992, when the Health and Welfare Ministry approved the use of IFN for treating chronic active hepatitis C. It is important to identify and treat depression, which is one of the psychiatric complications of IFN therapy and often leads to discontinuation of the therapy, in patients with chronic hepatitis C. In this study we prospectively investigated the incidence of depression during IFN therapy in patients with chronic active hepatitis C. The psychiatric status of 85 patients (53 men, 32 women; mean age 49.1 years) with chronic active hepatitis C who began receiving IFN at Showa University Hospital was assessed before and 2, 4, 12 and 24 weeks after the start of IFN therapy, using the major depressive episode diagnostic criteria listed in the DSM-III-R and the Hamilton Depression Scale HDS). All of the patients provided informed consent prior to participation in this study. IFN therapy was discontinued in 5 cases (5.9%) because of physical side effects and in 4 cases (4.7%) because of depression. Two, 11, 14, 25 and 16 patients were diagnosed as having major depressive episodes before and 2, 4, 12 and 24 weeks after the start of IFN therapy, respectively. The number of patients who were asymptomatic before the start of IFN therapy but were diagnosed as having a major depressive episode at least once during IFN therapy was 31 (31/83 = 37.3%). The mean HDS scores at 2, 4, 12 and 24 weeks (5.4, 6.0, 8.8 and 6.6) were significantly higher than that before the start of IFN therapy (3.0). The patients whose first diagnosed major depressive episodes occurred more than 4 weeks after the start of IFN therapy tended to be more severely depressed than those in whom it occurred less than 4 weeks after the start of IFN therapy. Compared to the 47 patients who completed 24 weeks of IFN therapy without experiencing depression, the 31 patients who were diagnosed as experiencing major depressive episodes during IFN therapy had significantly higher neuroticism scores determined using the Eysenck Personality Questionnaire, showed a more severely depressed mood and experienced more severe sleep disturbances before the start of IFN therapy. The latter group of patients also tended to have comorbid chronic physical disorders such as hypertension or diabetes mellitus and the histories of mental disorders before the IFN therapy; however these differences were not statistically significant. There were no differences between the two groups in patient age or sex, the severity of hepatitis before the IFN therapy, the type of IFN used in the therapy or the efficacy of IFN in the treatment of the hepatitis C. Our results indicate that the decision as to whether to treat chronic active hepatitis C with IFN should be made carefully and that early intervention and careful monitoring of depression are required during IFN therapy in the treatment of chronic active hepatitis C.

Adult↗
PubMed1994

[Evaluation of combination chemotherapy for advanced gastric carcinoma as a neoadjuvant chemotherapy with CDDP, MMC, etoposide and 5'-DFUR].

Seven cases of nonresectable gastric carcinoma with lymph node metastasis were treated with combination chemotherapy [CDDP 75 mg/m2 i.v. day 1 (A method: Ccr > or = 50 ml/min) or 20 mg/m2 i.v. day 1, 2, 4, 5 (B method: Ccr < 50 ml/min), MMC 10 mg/m2 i.v. day 1, etoposide 50 mg/body i.v. day 3, 4, 5, 5'-DFUR 2,100 mg/body po 4 day/week] every 4 weeks as a neoadjuvant chemotherapy. After treatment, the size of the primary tumor was reduced in four of seven cases. The lymph nodes disappeared in one case and were reduced in size in four cases. Metastatic liver tumors were found in four cases. They disappeared in one case and the size was reduced in one of seven cases. One patient with renal dysfunction was treated with B method. However, renal dysfunction did not become worse. Five patients were operated after chemotherapy. Absolute curative resection was performed in three of them. The total rate of curative resection was 43% (3/7). Four patients were alive for 19 months after operation. The main side effects of this therapy were nausea, anorexia and bone marrow suppression, which, were found in all patients. These results suggest that this combination chemotherapy is as effective as neoadjuvant chemotherapy for advanced gastric carcinoma.

Aged↗
PubMed1994

[A surgically treated case of aortic arch aneurysm complicated with right middle cerebral artery occlusion].

A 65-year-old male diagnosed as an aortic arch aneurysm by computed tomography and angiography was treated surgically with success. He had had cerebral transient ischemic attack, but no symptoms of central nervous system. Cerebral angiography revealed complete occlusion of the right middle cerebral artery. The aneurysm was resected and replaced with Gelseal knitted Dacron prosthesis under the selective cerebral perfusion combining deep hypothermia. During cardiopulmonary bypass cerebral perfusion pressure was maintained over 50 mmHg, and arterial carbon dioxide tension was controlled by alpha-stat method. To our knowledge this is the first case of surgically treated aortic arch aneurysm complicated with middle cerebral artery occlusion. This experience would be valuable to decide about indication for surgical treatment of an aortic arch aneurysm complicated with cerebral vascular disease.

Aged↗
PubMed1992

[A comprehensive fact finding study of home care elderly for planning of the community based rehabilitation system in Koga City, Ibaraki Prefecture].

An interview survey was held with the purpose of grasping the problems faced by the home care elderly living in Koga city in Ibaraki prefecture. The subjects of the study were 100 cases who had been registered as elderly requiring home care in the municipality. The main results were as follows: (1) The most frequent underlying disorders that were considered as causes of disabilities in the home care elderly were cerebrovascular diseases, senile dementia and external injuries. In 67 percent of the subjects, one of these three disorders had caused the disabilities. (2) Disabilities in self care activities and in mobility were closely related to each other and the order of the difficulty in performing these activities was similar in many cases. A large number of the subjects sustaining severe disabilities expressed discontent with their daily life. (3) Forty two percent of the subjects were so-called bedridden elderly who got out of bed for less than 3 hours a day. The Barthel index score was 60 or less in all of the bedridden subjects. (4) For most of the bedridden elderly, bed rest was not required and probably exacerbated the disuse syndrome. In order to ameliorate their condition, adequate rehabilitation programs and assistance in their daily activities need to be offered. (5) Seventy eight percent of the care givers complained about the burden of care. Those who had no assistant care giver complained more frequently. Many of the care givers complaining about their burden had their own health problems. (6) The utilization of social welfare services were not always without any problems. The number of the experts who can deal with the psychosocial aspects in the elderly should be increased in order to improve the situation.

Aged↗