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Katsumi Mori

Publications and source records attributed to Katsumi Mori.

9 recordsLinked to original sources

Phylogenetic analysis of Lactococcus lactis subspecies based on decoding the sequence of the pepT tripeptidase gene, the pepV dipeptidase gene and 16S rRNA.

Tripeptidase (PepT) and dipeptidase (PepV), the enzymes located in the final stage of the intracellular proteolytic system, were demonstrated to be distributed widely in lactic acid bacteria, especially in lactococci. Both the tripeptidase genes (pepT) and dipeptidase genes (pepV) of 15 lactococcal strains consisting of the type and domestic strains were cloned and sequenced using normal and TAIL PCR methods. Amino acid sequences of these enzymes were highly conserved among strains. Evolutionary distance trees based on the sequence of 1239 nucleotides of pepT and 1416 nucleotide of pepV showed a similar cluster as that obtained from the 1499 fragment of the 16S rRNA. Based on this profile, the species Lactococcus lactis is reasonably divided into three subspecies groups, subsp. lactis, cremoris, and hordniae, as in the current classification. Figure of trees from pepT and pepV were essentially identical to each other and slightly more intricate than that from 16S rRNA. The K nuc values obtained from pepT and pepV genes were approximately ten times as high as that from 16S rRNA. Considering these results, phylogenetic analysis based on pepT and pepV genes may aid in a more precise index of classification of L. lactis subspecies. PepT and PepV seem to have evolved in similar directions in lactococci.

Amino Acid Sequence↗

Attention disorders in schizophrenia.

In order to clarify the feature of attention disorders in schizophrenia, two tasks (X and AX) of the Continuous Performance Test (CPT) were given to 36 schizophrenic patients and 25 healthy controls. The schizophrenic patients performed considerably less well than normal controls. Performances were expressed in indices such as omission and commission errors, reaction time and discriminability. Among errors, omission in both the X and AX tasks was found to be an index that varied in reaction time, indicating difficulty in sustaining attention. Omission was found to act as a state-dependent index of schizophrenia in relation to inattentiveness in clinical settings and emotional disturbance in interpersonal situations. Commission, in contrast, differed between the two tasks, acting as an index of disinhibition of reaction in the X task, and of disturbance of the capacity and allocation of attention in the AX task. Commission was also thought to be an index related to thought disorder during episodes of acute schizophrenia, that is, it reflects an essential pathology in schizophrenia.

Adult↗

The alteration of odor-induced c-Fos immunoreactivity in the rat olfactory bulb after olfactory nerve transection.

We used the rats in which one olfactory nerve had been transected and observed the odor (Propionic acid) -induced c-Fos immunoreactivity in the bulb at different times (2, 4, 8 weeks) after nerve transection. The exposure to odor produced a strong cluster of c-Fos positive cells in the mediodorsal region of the intact bulb. On the other hand, the transected bulb showed much less reactivity 2 weeks after neurectomy; however, a large number of positive cells were observed in the whole of the bulb from 4 weeks after neurectomy. Furthermore, we measured the levels of mRNA for tyrosine hydroxylase (TH), which was the marker of odor-induced olfactory nerve activity in the bulb, by using real-time PCR. The level of TH mRNA decreased on the transected side at 2 weeks but recovered to the level of the contralateral side at 4 weeks after neurectomy. We firstly demonstrated that projection mapping of odor receptors was altered after olfactory nerve transection by using an immunohistochemical method.

Animals↗

Modulation of T-cell functions by laser surgery in patients with allergic rhinitis.

OBJECTIVE: Potassium-titanyl-phosphate (KTP) laser turbinectomy is an established treatment for hypertrophied inferior turbinates that do not respond to other medical treatments. KTP laser surgery is usually performed with the aim of reducing the size of hypertrophied inferior turbinates. We hypothesized that laser vaporation may also inhibit the allergic reaction in the nasal mucosa of inferior turbinates. MATERIAL AND METHODS: We examined the effect of KTP laser therapy on T-cell responses using peripheral blood mononuclear cells (PBMCs). RESULTS: Levels of T-cell proliferation after stimulation with Staphylococcus enterotoxin B (SEB) were higher in post- than pre-surgery patients. Levels of interferon-gamma and IL-2 produced by PBMCs after stimulation with SEB appeared to be higher in post- than pre-surgery patients. Serum levels of house dust-specific IgE were lower in post- than pre-surgery patients. These results indicate that KTP laser therapy modulates T-cell responses and probably tilts the Th1/Th2 balance towards the Th1-dominant state. CONCLUSION: KTP laser surgery eases or cures allergic rhinitis not only by reducing the volume of the inferior turbinates but also by modulating T-cell functions.

Adolescent↗

Factors affecting complete resection of gastric tumors by the endoscopic mucosal resection procedure.

BACKGROUND: In Japan, endoscopic mucosal resection (EMR) has been widely used as a treatment option for small early gastric cancer (EGC). The present study reviewed 178 cases for the 10-year period 1987-1997 in order to clarify the factors affecting the successful outcome of EMR. METHODS: Logistic regression analysis was used to examine whether complete resection of EGC correlated with the patient's age, gender, the characteristics of the tumor (location, macroscopic form, and size), the duration of the procedure and the experience of the doctor. RESULTS: The location of the tumor and the duration of the procedure correlated with the completeness of the resection (P < 0.01 and P < 0.05, respectively). Endoscopic mucosal resection was more difficult to perform for tumors in the gastric body than in the antrum or incisura region, and the longer the procedure the less complete the resection. CONCLUSION: The outcome of EMR is affected significantly by the location of the EGC.

Aged↗

Identification of a domain conferring nucleotide binding to the N-acetyl-d-glucosamine 2-epimerase (Renin binding protein).

Renin binding protein (RnBP), a cellular renin inhibitor, has been identified as the enzyme N-acetyl-D-glucosamine (GlcNAc) 2-epimerase. Our recent studies demonstrated that rat GlcNAc 2-epimerase has a ten-times higher affinity for ATP, dATP, and ddATP than the human enzyme [Takahashi, S. et al. (2001) J. Biochem. 130, 815-821]. To identify the domain conferring nucleotide binding to GlcNAc 2-epimerase, we constructed a series of chimeric enzymes successively replacing the three domains of the human enzyme (N-terminal, middle, and C-terminal domains) with the corresponding domains of the rat enzyme. Chimeras were expressed in Escherichia coli JM109 cells under the control of the Taq promoter. The purified chimeric enzymes had GlcNAc 2-epimerase activity and inhibited renin activity in a dose-dependent manner. The recombinant human and rat enzymes required catalytic amounts of ATP with apparent K(m) values of 73 and 5.5 microM, respectively. Chimeric enzymes of HHR, RHH, and RHR (H, human type domain; R, rat type domain) had nearly the same nucleotide specificity as the human GlcNAc 2-epimerase. On the other hand, HRR, HRH, and RRH chimeras had the same nucleotide specificity as the rat enzyme. These results indicate that the middle domain of the GlcNAc 2-epimerase molecule participates in the specificity for and binding of nucleotides, and that nucleotides are essential to form the catalytic domain of the enzyme.

Adenosine Triphosphate↗

Measuring relative work values for home care nursing services in Japan.

BACKGROUND: Japan's system of Home Visit Nursing Care Stations (Station) began in 1991. To maintain the quality of services in home health nursing provided by Stations, reimbursement needs to account not only for the number of home visits, but also for the time and intensity of nursing services. OBJECTIVES: This study aimed primarily to investigate the total work value and the three dimensions (time, mental effort, and physical effort) of actual visiting nursing services for the aged, and to quantify the contribution made by the three dimensions of nursing services to total work. The secondary purpose was to determine whether patient characteristics, nurse characteristics, and types of nursing services contributed to the variance in total work. Total work is defined as comprehensive work input of nursing services, with careful consideration given to both the intensity and duration of work. METHODS: Self-report questionnaires about actual visiting nursing services, based on the Resource-Based Relative Value Scale, were answered by 32 nurses from three Stations in urban Yokohama, Japan. RESULTS: Regression analysis showed that time and intensity (physical effort and mental effort) explained 96% the variance in total work. Time alone accounted for only 39% of the variance in total work. Patient characteristics, nurse characteristics, and service type accounted for less variance in total work than did time and intensity. CONCLUSIONS: The study findings indicate that reimbursement of nursing services should reflect not only the time required for each visit, but also the intensity of nursing services provided, including mental effort and physical effort.

Attitude of Health Personnel↗