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T Kamei

Publications and source records attributed to T Kamei.

At least 109 records · Page 6Linked to original sources
PubMed1997

Characterization of a mutant of Vibrio vulnificus for heme utilization.

Vibrio vulnificus, an opportunistic human pathogen, can obtain iron from a variety of heme proteins. This process involves the digestion of heme proteins by an exoprotease to liberate protoheme (iron-protoporphyrin IX). In the present study, we isolated and characterized a mutant for protoheme utilization. One mutant isolated by treatment with a chemical mutagen was shown to be unable to use either protoheme or heme proteins, but multiplied in a medium supplemented with an iron siderophore, such as iron-vulnibactin. Like a wild-type strain, the mutant sensed iron depletion, so that the 74- and 79-kDa outer membrane proteins were expressed under iron-regulated conditions. Both the parent and mutant strains secreted hemolysin independent of the iron concentration of the medium. Whole cells of either of the strains were equally capable of binding of hematin. Taken together, the data suggest that the mutant may have a mutation in a gene encoding an inner membrane or a periplasmic protein which transports protoheme or iron dissociated from protoporphyrin IX into the cell.

DNA, Bacterial↗
PubMed1997

Graft persistence effectively induces and maintains donor-specific unresponsiveness.

BACKGROUND: In the present study we attempted to evaluate the role of the graft as an alloantigen in induction and maintenance of donor-specific prolongation of allograft survival by short course(s) of FK506 treatment in rat heart transplantation. Materials and methods. In the WKA/Qdj-to-LEW combination group, FK506 (3 mg/kg/day, 7 days, s.c.) was administered from Day 0 after cardiac transplantation. A second WKA/ Qdj cardiac graft was transplanted on Day 14 into the LEW recipient after removal of the first graft on Day 3 or Day 7. In other groups an additional course of FK506 (3 mg/kg/day, 7 days, s.c.) was given from Day 35. A second WKA/Qdj cardiac graft was transplanted on Day 49 into the LEW recipient after removal of the first graft on Day 7 or Day 28. RESULTS: A short course of FK506 treatment allowed for survival prolongation of a cardiac allograft [mean survival time (MST) = 42.8 days]. Removal of the first graft on Day 7 (MST = 16.4 days) but not on Day 3 (MST = 10.2 days) caused donor-specific prolongation of the second allograft survival, which was significantly shorter than that in the recipient without the graftectomy (MST = 32.8 days). When graftectomy was performed on Day 3, there were immunohistochemically detectable levels of donor class II expressing cells in the recipient spleen on Day 7, indicating that the presence of the graft more effectively induced unresponsiveness than microchimerism alone. The additional course of FK506 treatment on Day 35 maintained graft survival (MST > 90.6 days). Removal of the first graft on Day 7 (MST = 13.5 days) or Day 28 (MST = 24.7 days) did not show significant prolongation of the second allograft survival, whereas significant survival prolongation of the second graft was observed in the recipient without the graftectomy (MST = 38.8 days). However, marked survival prolongation of the second donor-specific allograft in half of the recipients that had received the second course of FK506 treatment after graftectomy on Day 28 indicates that residual donor antigen can function as tolerizing antigen with an FK506 supplement. CONCLUSIONS: We concluded that the persistence of a graft more effectively induces and maintains donor-specific unresponsiveness than does the chimeric state of graft-derived cells alone under immunosuppression by FK506 in the rat heart transplantation model.

Animals↗
PubMed1997

Influence of lateral head tilting on head-shaking nystagmus.

We conducted a trial to determine whether or not head-shaking nystagmus (HSN) was influenced by lateral head tilting. Twenty-two patients with unilateral peripheral vestibular lesions were examined between July 1990 and June 1996. All of the patients were found to have horizontal HSN following horizontal head shaking in the upright head position. Eye movements were recorded by electronystagmography with the eyes open in complete darkness. Patients voluntarily tilted their heads to the lateral head positions with the assistance of the examiner as quickly as possible immediately after head shaking in the upright head position. Findings showed that monophasic horizontal HSN and the first phase of biphasic horizontal HSN were suppressed by lateral head tilting. The second phase of biphasic horizontal HSN was influenced differently by head tilting when compared with the first phase. Vertical (down-beating) components in horizontal HSN may appear in the peripheral vestibular lesions, but seem to have no definite relation to head positions.

Adult↗
PubMed1997

MRI in carcinomatous encephalitis.

We report a rare case of miliary brain metastases presenting with symptoms similar to encephalitis ("carcinomatous encephalitis"). Contrast-enhanced MRI demonstrated miliary metastases more distinctly than other imaging methods and reproduced the pathological features.

Adenocarcinoma↗
PubMed1997

Amyotrophic lateral sclerosis with numerous axonal spheroids in the corticospinal tract and massive degeneration of the cortex.

A 53-year-old woman developed bulbar palsy, spastic quadriplegia, amyotrophy, and supranuclear ophthalmoplegia, and thereafter her condition was managed with mechanical ventilation for 1 year. Her total clinical course was 6 years. The autopsy examination revealed neuronal loss with reactive astrocytosis in the precentral cortex, thalamus, mammillary body, amygdala, putamen, globus pallidus, subthalamic nucleus, and the substantia nigra, in addition to degeneration of lower motor neurons, some of which contained Bunina bodies. Along the corticospinal tract, there were severe axonal loss and numerous axonal spheroids, which were positive for phosphorylated neurofilament, ubiquitin, and synaptophysin, and lipid-laden macrophages in the centrum semiovale to the crus cerebri. Ballooned neurons, which were positive for phosphorylated neurofilament, were occasionally seen in the frontal cortex. Although in the common form of amyotrophic lateral sclerosis (ALS) both upper and lower motor neurons are mainly involved, the corticospinal tract degeneration cannot be traced rostral to the pons. The noteworthy features in our patient were the precentral cortical degeneration and axonal spheroids in the corticospinal tract rostral to the pons. It remains unclear why axonal spheroids in the corticospinal tract and precentral cortical degeneration are not observed in most ALS cases. Whether their development depends on the clinical duration, mechanical ventilator management, or some other factors remains an open question.

Amyotrophic Lateral Sclerosis↗
PubMed1997

Instrumentation of a handy microscopic probe for concurrent observation and measurement of active sweat secretion, and its applications.

Instrumentation for the concurrent, dynamic monitoring of active sweat glands and perspiration volume is described. A device for the measurement of the rate of sweat secretion was installed on the head part of a microscope. The combined apparatus (microscopic probe) is handy for use and its weight is very light (ca. 300 g). The microscopic probe is easily attached to the surface of human skin. The dynamic activities of the sweat glands on the forehead and nose and under the nose were observed and measurement when thermal, mental and physical stimuli were applied. The activities of individuals sweat glands were asynchronous when observed in units of a few seconds or less; however, they worked synchronously in a unit period of several seconds. The latter were recorded as fine peaks by a strip chart recorder. The proposed system may be useful for the study of the sympathetic nervous system, the skin sympathetic reflex and the working of sudomotor nerves.

Adult↗
PubMed1997

Hepatocyte growth factor and neutrophil elastase in idiopathic pulmonary fibrosis.

It has been hypothesized that hepatocyte growth factor (HGF) may play an important role in regulating the growth of lung epithelium and in the regeneration of the lung as a paracrine or endocrine factor in idiopathic pulmonary fibrosis (IPF). Based on this background, serum HGF was measured in 31 IPF patients (21 male/10 female, median age 60 years). Fifteen age-matched normal non-smokers served as the control. Hepatocyte growth factor was measured by enzyme-linked immunosorbent assay with monoclonal and polyclonal antibodies against human HGF (Otsuka Assay Laboratories, Tokushima, Japan). Elastase: alpha 1-proteinase complex was also measured by enzyme-linked immunosorbent assay. No patients had significant liver or renal dysfunction. As a result, mean (standard error) serum HGF concentration of the patients with IPF was 0.384 (0.022) ng ml-1, which was significantly high compared to normal non-smokers [0.213 (0.012) ng ml-1, P < 0.001, 95% confidence interval was between 0.104 and 0.238]. Serum HGF values correlated strongly with the plasma elastase: alpha 1 proteinase inhibitor complex (R = 0.679, P < 0.001). Immunohistochemical staining of lung tissue with anti-human neutrophil elastase showed scattered immunopositive cells mainly in interstitium. Immunohistochemical staining with mouse anti-human HGF antibody showed that HGF was distributed to the lung epithelial cells in IPF lung specimens obtained by open lung biopsy. These results suggest that HGF may play an important role in the pathogenesis of IPF.

Bronchoalveolar Lavage Fluid↗
PubMed1997

EEG-driven photic stimulation effect on plasma cortisol and beta-endorphin.

The effect of EEG-driven photic stimulation on stress-related endocrine function was studied. Subjects were 16 healthy males divided into a photic stimulation group (n = 8) and a control group (n = 8). Electrodermal and emotional lability measures were assessed by nonspecific skin conductance response and the Maudsley Personality Inventory, respectively. Plasma cortisol and beta-endorphin concentrations were measured both before and after EEG-driven photic stimulation as well as the resting condition. Subjects with electrodermal, emotional, or both lability showed comparable decreases of plasma beta-endorphin on photic stimulation as did the stable subjects. Under resting control conditions, however, they showed significant increases of beta-endorphin compared to both stable subjects as well as the photic stimulation condition. In addition, labile subjects showed significant alpha enhancement on photic stimulation compared to stable subjects and to the resting control condition. The data suggest that increases of plasma beta-endorphin in labile control subjects may denote a stress response to the conditions of these experiments, and that any decrease by EEG-driven photic stimulation may indicate a reduction of responsiveness to an acute stress.

Adult↗
PubMed1997

Signaling pathways controlling trophoblast cell differentiation: Src family protein tyrosine kinases in the rat.

Trophoblast giant cell differentiation is characterized by endoreduplication and expression of members of the prolactin (PRL) gene family and can be simulated in vitro via manipulations of the Rcho-1 trophoblast cell line. The regulation of trophoblast cell proliferation and differentiation involves tyrosine protein kinase signaling pathways. Treatment of Rcho-1 trophoblast cells with tyrosine kinase inhibitors disrupted differentiation-dependent expression of members of the PRL gene family and cytoskeletal organization. Activated p60c-src, p62c-yes, and p53/56lyn were present in the Rcho-1 rat trophoblast cell line and in differentiated trophoblast cells isolated from the developing rat placenta. p60c-src and p62c-yes were active in proliferating and differentiating trophoblast cells. During proliferation, p62c-yes exhibited distinct associations with other phosphoproteins (34, 66, 76, and 150 kDa). p53/56lyn was activated only in differentiating trophoblast cells. p53/56lyn showed a differentiation-dependent accumulation in cytoskeletal and membrane fractions, whereas p60c-src levels were virtually invariant in both fractions. Expression patterns of csk, a negative regulator of Src family kinase activities, were not consistent with its involvement in the differentiation-dependent activation of p53/56lyn; however, there was some indication of the participation of a tyrosine phosphatase in the regulation of p53/56lyn. In conclusion, p60c-src, p62c-yes, and p53/56lyn patterns of activation in trophoblast cells are consistent with their involvement in the control of trophoblast cell proliferation and differentiation.

Animals↗
PubMed1997

An autopsy case of diffuse malignant mesothelioma of the pericardium.

A report is presented of an autopsy case of a 71-year-old Japanese man with a diffuse malignant epithelial mesothelioma of the pericardium with massive pericardial effusion and a thickened pericardium. He had no history of exposure to asbestos. He suffered severe heart failure and later died. Autopsy revealed that the tumor had developed over the pericardium. Microscopically, the tumor cells were arranged in an epithelial form, and histochemically, the cytoplasm of these cells contained glycogen and hyaluronic acid. The tumor tissue showed immunohistochemical positivity for cytokeratin, epithelial membrane antigen, vimentin, cancer antigen 125, thrombomodulin, mesothelial antigen, muscle actin and human milk fat globule. In contrast, all the tumor cells were negative for human carcinoembryonic antigen and epithelial antigen. Ultrastructurally, the tumor cells had long, thin microvilli, abundant intermediate filaments, intracytoplasmic lumina and long desmosomes. It is considered that the patient had a typical malignant epithelial mesothelioma of the pericardium.

Aged↗
PubMed1997

Changes of immunoregulatory cells associated with psychological stress and humor.

For 8 medical students influences of psychological stress or humor on T-cell subset percentages and natural killer cell activity were investigated by measuring these parameters before and after an examination and before and after watching a comedy video. Although T-cell subsets were not significantly affected by either stimulus and natural killer cell activity was not affected by the examination, the latter was significantly decreased after watching the comedy video.

Adult↗
PubMed1997

[Four cases of carotid body tumor--especially the usefulness of CT and MRI in preoperative diagnosis].

Four cases of carotid body tumor are reported. Surgical removal of the tumor was performed in all cases. The internal carotid artery (ICA) was preserved in only two cases. In the other two cases ICA was unavoidably replaced by an EPTFE (expanded polytetrafluoroethylene) graft. In addition to the size and mobility in the anterior and posterior direction of the tumor, we concluded that CT and MRI were useful in decision of the surgical method. In case the ICA cannot be distinguished from the tumor at the bifurcation of the carotid artery on enhanced CT, it should be considered to be difficult to remove the tumor. MRI is suitable for discerning the inner surface of the carotid artery, but it is significant that MRI cannot necessarily reveal tumor invasion of the carotid artery wall.

Adult↗
PubMed1997

[Development of "assessment guideline of family power for healthy life"].

The purpose of this study is to develop "assessment guideline of family power for healthy life" aiming at expanding self-care power of family in community nursing practice. The subjects of this study covered those families in one hundred and fifty six instances that we had seized as subject for nursing care and study. The method of this study had constructed assessment guideline inductively out of each case, and modified it by applying to cases of families with health problems and others. As a result, we had formed nine items of "family power for healthy life" and three items of "conditions influencing family power for healthy life" for "assessment guideline of family power for healthy life".

Community Health Nursing↗
PubMed1997

[Effects of oxitropium bromide on exercise and lung function in patients with pulmonary emphysema].

Anticholinergic drugs have been reported to be effective in pulmonary emphysema. We studied the effects of the anticholinergic drug oxitropium bromide on exercise capacity and lung function in patients with this disease. We studied 11 men and 1 women, aged 69.3 +/- 4.5 yrs, in whom chest radiography showed pulmonary emphysema. Before and after the subjects inhaled two puffs of oxitropium bromide, they walked in a corridor for 12 minutes, and the distance they walked and spirometric data were recorded. FVC and FEV1 were significantly higher after inhalation of the drug. FEV1% did not change, and the distance walked increased slightly. We also studied symptoms and peak expiratory flow rate in 37 patients with pulmonary emphysema before and after the start of therapy with inhaled oxitropium bromide. Symptom scores of wheezing and sleep improved, and peak expiratory flows increased significantly. We conclude that inhaled oxitropium bromide can improve lung function and slightly increase exercise capacity in patients with pulmonary emphysema. These effects may be caused by bronchodilation-induced increases in FEV1 and FVC. Monitoring of peak expiratory flow in patients with pulmonary emphysema may be useful for evaluating the clinical effectiveness of oxitropium bromide.

Aged↗
PubMed1996

Placental lactogen-I variant utilizes the prolactin receptor signaling pathway.

Placenta lactogen-I variant (PL-Iv) is a member of a family of proteins expressed by the rat placenta with characteristics similar to prolactin (PRL). In this report, we present the molecular cloning, chromosomal localization, and heterologous expression of PL-Iv. Nucleotide sequence analysis of the PL-Iv cDNA clone predicted a precursor protein of 223 amino acids, including a 28-amino acid signal sequence. The PL-Iv gene was localized to chromosome 17 of the rat genome, which also carries other members of the PRL gene family. PL-Iv heterologously expressed in Chinese Hamster ovary (CHO) cells exhibited similar immunoreactive and electrophoretic characteristics with PL-Iv produced by the rat placenta. N-terminal sequencing verified the identity and purity of the recombinant PL-Iv species and the site of cleavage of the signal peptide from the mature secreted PL-Iv species. Recombinant PL-Iv was shown to bind to ovarian and liver PRL receptors, stimulate the proliferation of Nb2 lymphoma cells, and activate Jak2. Each of these actions is consistent with PL-Iv utilizing the PRL receptor signal transduction pathway.

Animals↗
PubMed1996

The effect of overall treatment time of radiation therapy on local control of T1-stage squamous cell carcinoma of the glottis.

From 1975 to 1990, 72 patients with T1 glottic cancer, excluding a verrucous type of carcinoma, were treated with radiation therapy (RT). All treatments were given with a standard fractionation of 2 Gy per day. The total dose to the tumor ranged from 60 to 70 Gy. Six patients received a split-course RT. The overall local control rate was 87% at 5 years. Forty-one patients who completed RT in 45 days or less had a 5-year local control rate of 95%. Sixteen patients who completed a treatment course in 46 to 49 days had a local control rate of 81%. Fifteen patients with a treatment course of more than 50 days had a local control rate of 73%. There was a statistically significant difference in local control rates among the three groups (P<.05). The split-course RT group had a 5-year local control rate of 50%; that rate was statistically significantly inferior to that of the continuous course group (P<.001). Multivariate analysis also showed that an interruption of the treatment course was an important parameter in relation to the local control. The prolongation of standard RT schedules adversely affected local control of T1 glottic carcinoma and, therefore, should be avoided whenever possible.

Carcinoma, Squamous Cell↗
PubMed1996

[Late phase II study of LY188011 (gemcitabine hydrochloride) in patient with non-small-cell lung cancer. Gemcitabine Late Phase II Cooperative Study Group A)].

A late phase II study of LY188011 (gemcitabine hydrochloride), a new synthetic anticancer agent, was conducted at 20 Japanese institutions to evaluate the efficacy and safety of the agent administered alone in patients previously untreated with chemotherapy for primary non-small-cell lung cancer (NSCLC). All of the total 73 patients enrolled were eligible and 69 completed at least one course of LY188011 therapy. All patients were evaluated for safety. The response rate was 26.0% (19/73) of eligible patients. The most common adverse reactions included decreased hemoglobin, leukopenia, neutropenia, anorexia, nausea/vomiting, and malaise. Most adverse reactions were of grade 1 or 2 and only a few grade 3 or 4 reactions were reported. However, since a death occurred due to interstitial pneumonia, careful observation for this event is needed. Based on these results, it may be concluded that LY188011, a new anticancer agent, has adequate efficacy for the treatment of NSCLC and causes few clinically relevant adverse reactions.

Adenocarcinoma↗