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T Kashiyama

Publications and source records attributed to T Kashiyama.

At least 19 recordsLinked to original sources
PubMed2001

Functional expression of a chimeric myosin-containing motor domain of Chara myosin and neck and tail domains of Dictyostelium myosin II.

We succeeded in expressing a chimeric myosin that comprises the motor domain of characean algal myosin, (the fastest known motor protein), and the neck and tail domains of Dictyostelium myosin II. Although the chimeric myosin showed an ATPase activity comparable to that of muscle myosin (15 times higher than that of the wild-type Dictyostelium myosin II), the motile activity of the chimera was only 1.3 times higher than that of the wild-type. However, this is the first chimeric myosin that showed motile activity faster than at least one of the parent myosins. It was suggested, therefore, that the motor domain of Chara myosin has the potential for performing fast sliding movement.

Actins↗
PubMed2001

Effects of Ca(2+) and calmodulin on the motile activity of characean myosin in vitro.

It is well known that the cytoplasmic streaming of characean cells is readily inhibited by Ca(2+). However, neither the actin-activated MgATPase nor the in vitro motile activity of purified characean myosin were inhibited by Ca(2+). Recently, amino acid sequence of characean myosin was determined in our laboratory and the sequence revealed that characean myosin contains six calmodulin binding sites in the neck region. We also detected calmodulin in quickly prepared characean myosin fraction. It is, therefore, possible that the insensitivity of characean myosin to Ca(2+) is due to the dissociation of some calmodulin molecules from the neck region during the course of protein purification. To determine strictly the Ca(2+) sensitivity of characean myosin, we intentionally used crude preparation of characean myosin to reduce the possibility of calmodulin dissociation and examined the motile activity of characean myosin in vitro in the presence of excess characean calmodulin. We could not observe any drastic inhibition of characean myosin activity by Ca(2+). The results suggest that the brief cessation of cytoplasmic streaming is not caused by the direct inhibition of myosin activity by Ca(2+).

Actins↗
PubMed2001

[Meningococcocemia complicated by disseminated intravascular coagulation, splenic infarction and pulmonary thromboembolism in a young adult: case report].

Mortality of meningococcal septicemia remains high in spite of the improvement of antibiotics treatment and critical care medicine. A 23-year-old male, who had been well until a day earlier, was admitted to the hospital because of a high-grade fever and headache. On the second hospital day, he was still febrile, and it was confirmed that he had disseminated intravascular coagulation. There was no purpuric skin lesion, and a lumbar puncture revealed no abnormality. The condition was complicated by a splenic infarction on the second hospital day, and he suffered a pulmonary infarction on the 8th hospital day. The blood culture was positive for Neisseria meningitidis, making the diagnosis meningococcal septicemia. He was successfully treated with antibiotics and intensive care. Although meningococcocemia in adults is relatively rare in Japan, the disease mortality is still high even in the modern era. Then, once the diagnosis is suspected, it is essential to keep in mind that meningococcal infection requires early recognition of the disease process, prompt initiation of adequate antiinfectious therapy and intensive treatment of multiorgan failure.

Adult↗
PubMed2001

[Cave-associated acute pulmonary histoplasmosis in two Japanese returning from Mexico].

We report cases of cave-associated acute pulmonary histoplasmosis that occurred in two Japanese returning from Yucatan, Mexico. Patient 1 is a 35-year-old woman who worked in a bat-infested cave in Mexico for about 3 weeks. Almost all her colleagues had developed cough, fever and headache after 5 days in the cave. She was asymptomatic but her chest radiograph showed multiple nodules 5-10 mm in diameter throughout both lungs. The histoplasmal mycelial-phase complement fixation titer on admission was 1:16, and 1:128 one month later. Patient 2, the 53-year-old husband of patient 1, was also infected by histoplasma in the cave, and similar nodules were observed in his chest radiograph. His histoplasmal complement fixation titer did not elevate. To date, about 20 cases of pulmonary histoplasmosis have been reported in Japan. The number of imported mycoses in Japan is increasing, and histoplasmosis should be considered in the differential diagnosis of pulmonary nodules in travelers returning from endemic areas.

Acute Disease↗
PubMed2001

[Multiple cavitary pulmonary metastases from ovarian cancer: a case report].

Cavitation in pulmonary metastases is thought to be uncommon. To date, few cases of pulmonary metastases originating from ovarian cancer and showing cavitation have been reported. We report a patient with multiple cavitation in pulmonary metastases from ovarian mucinous cystadenocarcinoma. A 28-year-old woman was admitted to our hospital presenting with cough and fever. The patient had undergone right ovariectomy for ovarian mucinous cystadenocarcinoma at the age of 23 years. Her chest radiograph on admission showed multiple cavities associated with infiltration in both lungs. Histological sections obtained by transbronchial lung biopsy revealed mucus-secreting adenocarcinoma, and a diagnosis of metastatic lung cancer from the ovary was made. Computed tomographic (CT) scans of the chest demonstrated various findings, including multiple thick-walled cavities, thin-walled cavities, air-space consolidations, ground glass opacities, and centrilobular nodular shadows formed by aspiration of the mucinous secretions. It is important to recognize that cavitation can occur in pulmonary metastases from ovarian cancer.

Adult↗
PubMed2001

[Simultaneous bilateral pneumothorax complicating Pneumocystis carinii pneumonia in a homeless man with AIDS].

Although pneumothorax is a well-known complication of AIDS related Pneumocystis carinii pneumonia, simultaneous bilateral pneumothorax has not been reported in Japan. A 54-year-old homeless man was admitted with emaciation and dyspnea. Chest X-ray showed diffuse ground glass opacity. Computed tomography of the chest demonstrated ground glass opacity and cyst-like lesions in both upper lobes of the lung. The patient was HIV positive. Grocott's stain of a bronchial lavage specimen demonstrated Pneumocystis carinii microorganisms. Intravenous trimethoprim-sulfamethoxazol and steroid administration was started. Seven days later, the patient developed tension pneumothorax of the right lung. Immediately after the thoracostomy, contralateral pneumothorax developed. Another chest tube was inserted. Subsequently, the patient died from bilateral pneumothorax. The endemicity of HIV infections among the homeless population is already a significant problem in Western countries. We should be aware that HIV infection may become a problem among the Japanese homeless as well.

AIDS-Related Opportunistic Infections↗
PubMed2000

Cloning and characterization of a myosin from characean alga, the fastest motor protein in the world.

In characean algae, very rapid cytoplasmic streaming is generated by sliding movement of an unconventional myosin on fixed actin cables. The speed of this sliding movement is the fastest among many molecular motors known so far. We have cloned a set of overlapping cDNAs encoding the heavy chain of this myosin by immunoscreening with antibody raised against characean myosin. The molecular mass of this heavy chain is 248 kDa, and the protein has a conserved motor domain, six IQ motifs, an extensive alpha-helical coiled-coil domain, and a C-terminal globular domain. Phylogenetic analysis suggested that this myosin belongs to class XI.

Amino Acid Motifs↗
PubMed2000

[Outbreak of hepatitis A virus infection among men who have sex with men].

We have recently encountered an outbreak of hepatitis A in Tokyo. Between July 1998 and November 1999, 21 patients were treated at our hospital. They were all male and 18 patients (86%) had had sex with men (MSM). About a half of the patients were seropositive for syphilis, hepatitis B and HIV. The VP1/2A region could be amplified by nested PCR in 6 of the 21 patients. They had the same sequences and were grouped into genotype IA. Homosexual activity should be kept in mind as a leading risk factor for hepatitis A in the recent Japanese population.

Acute Disease↗
PubMed1999

Myosins from plants.

Molecular cloning and sequence analysis of myosin genes from Arabidopsis thaliana and electron microscopic observation of a myosin from characean alga have revealed that overall structure of plant unconventional myosins is similar to that of the class V myosins. These plant unconventional myosins have two heads, a coiled-coil tail of varied length and a globular tail piece at the end. The tail piece is probably a site for membrane interaction. Characean myosin is of special interest because it can translocate actin filaments at a velocity several times faster than muscle myosin, which must have evolved to support the quick movement of animals in the struggle for their lives.

Adenosine Triphosphatases↗
PubMed1999

[Pneumonia among the homeless].

Although there are some studies concerning tuberculosis among the homeless persons in Japan, almost no detailed analysis is available about non-tuberculous lung infections in this population. We retrospectively studied the clinical features and microbial etiology of pneumonia among the homeless. This series included twenty so-called homeless persons, 19 male and one female, who were admitted to our hospital with a clinical diagnosis of pneumonia from April 1993 to July 1996. The average age was 56 years-old. All patients were transferred by ambulance. Most of them were admitted night in the winters, and had respiratory failure together with other serious complications such as gastrointestinal disease, liver failure and cerebrovascular disease. Chest X ray revealed so-called lobar pneumonia in 8 of 20 cases (40%). Microbial etiologic agents were found in 14 patients (70%). Pneumococcus amounted to 80% of all the speculated pathogens. Despite intensive care after admission, 6 of 20 patients (30%) died subsequently. Although fatal pneumococcal pneumonia were reported to have decreased in the general population in Japan, morbidity and mortality of pneumococcal pneumonia was very high in this series.

Adult↗
PubMed1997

[Pulmonary Kaposi's sarcoma in a patient with the acquired immunodeficiency syndrome].

Cutaneous Kaposi's sarcoma (KS) is a well-known manifestation of the acquired immunodeficiency syndrome, but pulmonary KS is very rare in Japan. We encountered a 27-year-old Japanese, homosexual man who had extensive pulmonary KS. He came to our hospital because of a cough and dyspnea. On admission, there were some small nodules on the skin, and examination of a biopsy specimen led to the diagnosis of KS. The test for the human immunodeficiency virus antibody was positive and the CD4+ cell count was 69 per cubic millimeter. A radiograph of the chest showed multiple diffuse nodules, linear opacities, and some pleural effusion. Computed tomography also revealed multiple nodules and linear densities distributed along the bronchovascular bundles. Bronchoscopic examination revealed diffuse erythematous changes of the bronchial mucosa with some red polypoid lesions, which was compatible with endobronchial KS. Hypoxia developed one month after bronchoscopy. Two courses of chemotherapy with bleomycin and vincristine were given, and resulted in temporary improvement. A definite diagnosis of KS was made by necropsy.

Acquired Immunodeficiency Syndrome↗
PubMed1995

Wegener's granulomatosis with multiple cranial nerve involvements as the initial clinical manifestations.

Wegener's granulomatosis (WG) is a disease of unknown origin characterized by necrotizing granulomas of both the upper and lower respiratory tracts and glomerulonephritis. A 62-year-old woman presenting unusual neurological manifestations is reported. The patient suffered from palsies of multiple cranial nerves without manifestation of respiratory tracts in the initial clinical course. Seven years after the onset, pulmonary consolidations appeared on the chest X-ray study. A diagnosis was made by a needle biopsy of the lung. Palsies of cranial nerves suspected to be due to meningeal involvement of WG. During the entire clinical course, no finding of glomerulonephritis was observed.

Cranial Nerve Diseases↗
PubMed1995

[Sarcoidosis with hypercalcemia and increased 1 alpha, 25-dihydroxyvitamin D in lung tissue].

A 60-year-old woman was admitted to our hospital complaining of nausea, thirst, and dyspnea on exertion. She had skin eruptions on her back and right knee. Her serum calcium level was 12.6 mg/dl. The chest roentgenogram showed diffuse nodular shadows in both lung fields. The level of angiotensin-converting enzyme in serum was markedly high, and epithelioid cell granulomas were found in the specimens obtained by skin biopsy and by transbronchial lung biopsy. Sarcoidosis was diagnosed. After administration of prednisolone, the serum calcium level decreased to within the normal range and the shadows on the chest roentgenogram resolved. Hypercalcemia complicated with sarcoidosis is caused by overproduction of 1 alpha,25-dihydroxyvitamin D in granulomas. The content of 1 alpha, 25-dihydroxyvitamin D in the transbronchial lung biopsy specimen from this patient was higher than that from a sarcoidosis patient whose serum calcium level was normal. A few case reports of sarcoidosis with hypercalcemia have been published in Japan. The association with HLA type and the possibility of overintake of dietary vitamin D are discussed in reference to hypercalcemia in this patient.

Calcitriol↗
PubMed1994

[Hodgkin's disease initially presenting as vertebral lesions and a solitary pulmonary nodule--a case report].

Hodgkin's disease rarely involves bones and lungs without causing marked lymph node enlargement. The case of a 36 year old man, who initially presented with vertebral lesions and a solitary nodule in the lung, is reported. At the initial presentation, no apparent lymph node enlargement was observed. Pathological examination of the specimens obtained at vertebral surgery and needle biopsy of the lung suggested a presumptive diagnosis of Histiocytosis X. However, a definite diagnosis of the Hodgkin's disease was made by biopsy of a cervical lymph node which newly enlarged about two years after his initial presentation. This case suggests variability in the clinical feature of Hodgkin's disease.

Adult↗
PubMed1994

[A case of Wegener's granulomatosis with episcleritis, mediastinal lesions, and pleural effusion and without serum anti-neutrophil cytoplasmic antibodies].

We report a 63-year-old male case of Wegener's granulomatosis. His complaints were cough and fever, and chest X-ray showed subpleural infiltrative opacities in the bilateral lungs and small nodular lesions in the middle portion of the right lung. He had been treated as bacterial pneumonia at another hospital without any improvement and was referred to this hospital. Chest CT scan disclosed several small nodular lesions in the subpleural region of the right lung, consolidation in the posterior mediastinum, and the left pleural effusion. Transbronchial lung biopsy revealed inflammatory granulation with predominantly lymphocytes and micro-necrosis in the peribronchiolar region. Although these findings suggested Wegener's granulomatosis, open lung biopsy was performed because both antineutrophil cytoplasmic antibodies (ANCA) and antibodies to proteinase-3 were negative and ear, nose, and throat abnormalities were not found. Pathologic findings consisted mainly of granulomatous inflammation with lymphocytes, histiocytes, and multinucleated giant cells, and granulomatous vasculitis with micro-necrosis. Furthermore, the patient was diagnosed as having bilateral episcleritis by an ophthalmologist. No renal involvement was found. Standard treatment with cyclophosphamide and glucocorticoid resulted in marked improvement within a couple of weeks, and the patient was in complete remission eight months after initiation of therapy. This case is of interest in that the distribution of lesions was not typical and ANCA was negative.

Antibodies, Antineutrophil Cytoplasmic↗