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Biomedical subjects

A Kondo

Publications and source records attributed to A Kondo.

At least 235 records · Page 13Linked to original sources
PubMed1994

Overproduction and purification of Lon protease from Escherichia coli using a maltose-binding protein fusion system.

Lon protease, which plays a major role in degradation of abnormal proteins in Escherichia coli, was overproduced and efficiently purified using the maltose-binding protein (MBP) fusion vector. The MBP-Lon fusion protein was expressed in a soluble form in E. coli and purified to homogeneity by amylose resin in a single step. Lon protease was split from MBP by cleaving a fusion point between MBP and Lon with factor Xa and purified by amylose resin and subsequent gel filtration. In this simple method, Lon protease was purified to homogeneity. Purified MBP-Lon fusion protein and Lon protease showed similar breakdown activities with a peptide (succinyl-L-phenylalanyl-L-leucyl-phenylalanyl-beta-D-methoxynaphthyl amide) and protein (alpha-casein) in the presence of ATP. Therefore, the gene-fusion approach described in this study is useful for the production of functional Lon protease. MBP-Lon fusion protein, which both binds to the amylose resin and has ATP-dependent protease activity, should be especially valuable for its application in the degradation of abnormal proteins by immobilized enzymes.

2-Naphthylamine↗
PubMed1994

Does the extent of lymph node dissection affect the postoperative survival of patients with gastric cancer and disseminating peritoneal metastasis?

For patients with gastric cancer and either P1 or P2 peritoneal metastasis, no definite consistent policy with respect to the extent of lymph node dissection has yet been established. In palliatively gastrectomized patients, we analyzed the relationship between the extent of lymphadenectomy and postoperative survival. In patients with P1, an R2 or R3 lymphadenectomy was associated with a significantly improved postoperative survival as compared to an R1 dissection, while this, however, was not the case in patients with P2. As this study was not intended to be a prospective randomized study, a definite conclusion should be avoided. However, our findings suggest that in patients with P1, surgery should not be confined to a resection of the primary lesion, but should also include an R2 or R3 lymphadenectomy.

Female↗
PubMed1994

Total cystectomy after intravesical bacillus Calmette-Guérin (Tokyo strain) therapy for superficial bladder cancer: experience in Japan.

To clarify which patients might most require total cystectomy after intravesical bacillus Calmette-Guérin (BCG) therapy, we reviewed data for 111 individuals with superficial bladder cancer. Of the 111 patients, 73 received the BCG treatment for prophylaxis of intravesical recurrence after transurethral resection (group 1), 24 therapeutically for Ta or T1 tumours (group 2), and 14 for eradicating carcinomas in situ (CIS, group 3). Although the BCG therapy significantly reduced frequencies of recurrence in group 1, 27 patients (37%) did develop tumours again. Tumours disappeared in 18 of 24 patients (75%) in group 2, and in 11 of 14 (79%) in group 3. The rate of disease progression was 6% for all 111 patients: 3% (2/73) for group 1, 17% (4/24) for group 2, and 7% (1/14) for group 3. A total of 16 of the 111 patients (14%) underwent total cystectomy, the respective figures being 7% in group 1, 29% in group 2, and 29% in group 3. Indications for total cystectomy were progression in 7, recurrent multiple tumours in 5, persistent CIS in 2, a contracted bladder in 1, and occurrence of bilateral renal pelvic cancer in 1. Thus, 4 of 6 patients (67%) who had tumours unresponsive to BCG therapy in group 2 demonstrated progression and necessitated total cystectomy. Because tumours persisting after BCG therapy are frequently of the muscle-invasive type, such cases should be regarded as candidates for immediate total cystectomy.

Administration, Intravesical↗
PubMed1994

Germinoma in siblings: case reports.

We present the first reported cases of germinoma occurring in siblings of different genders. One tumor occurred in the left basal ganglia of a 7-year-old boy and the other in the suprasellar region of his 9-year-old sister. Both tumors were diagnosed as germinoma of two-cell pattern based on light and electron microscopic studies. Possible genetic factors responsible for this phenomenon are discussed.

Adolescent↗
PubMed1994

A phase II clinical trial of recombinant human tissue-type plasminogen activator against cerebral vasospasm after aneurysmal subarachnoid hemorrhage.

The results of a Phase II clinical trial of intrathecal recombinant tissue-type plasminogen activator for the prevention of vasospasm were reported. The subjects were 53 patients with aneurysmal subarachnoid hemorrhage (SAH), Groups 2 to 4 in Fisher's preoperative computed tomography classification and Grades II to IV in the Hunt-Kosnik classification. Twenty-four hours after surgery, tissue-type plasminogen activator (TD-2061) was intracisternally administered via a catheter (0.1, 0.2, or 0.4 mg, three times daily for 5 days). The clot-dissolving effects assessed as "effective" and "markedly effective" were virtually the same in the 0.1- and 0.2-mg groups (66.7% and 64.3%, respectively) but slightly lower (53.3%) in the 0.4-mg group, suggesting an adequate effect in the 0.1- and 0.2-mg groups. Severe angiographic vasospasm was not observed in any of three groups. No intergroup differences were noted in the incidence of symptomatic vasospasm, low density on computed tomography 1 month after SAH, and functional prognosis. Bleeding complications were noted in 4 patients (7.5%), including 1 case of SAH in the low 0.1-mg group, 2 cases of SAH in the 0.2-mg group, and 1 case of epidural hematoma in the 0.4-mg group. In overall safety rating, 3 cases with increased SAH and 1 case of epidural hematoma were assessed as "safety doubtful." Other minor side effects such as headache and hepatic dysfunction attributed to the effect of other simultaneously used drugs were assessed as "almost safe," and the rate of "almost safe" and "better" for all dose groups was about 90%, suggesting a safe dose level for all groups. These results suggest that repeated intrathecal administration of tissue-type plasminogen activator is useful for preventing vasospasm even in the low dose of 0.1 mg.

Adult↗
PubMed1994

Unusual presentation of brain metastasis from hepatocellular carcinoma--two case reports.

Two unusual cases of brain metastasis from hepatocellular carcinoma (HCC) are described. A 15-year-old boy presented with intracerebral hemorrhage from brain metastasis from HCC, and died of rebleeding 1 month after surgery. Cerebral metastatic HCC in a child is quite rare, and has not previously been reported. A 65-year-old male with a 2-year history of treatment for HCC presented with a brain metastasis from HCC without intracerebral hematoma manifesting as gradual onset of headache. Brain metastases from HCC presenting without intracerebral hemorrhage are rare.

Adolescent↗
PubMed1994

[Identification of Mycobacterium avium and Mycobacterium intracellulare using DNA probe test, and their ratio in Niigata area].

Using Gen-Probe test, both the Mycobacterium avium and Mycobacterium intracellulare strains were identified in the 76 disease-associated Mycobacterium-avium complex (MAC) strains isolated in the NIIGATA area. The following results were obtained: 1) Fifty-four MAC strains (71.1%) reacted with M. avium-probe and 22 strains (28.9%) reacted with M. intracellulare-probe. 2) There were no significant differences between the ratio of two strains before and after 1991. 3) The ratio of female cases with M. avium was significantly higher (22/32) in the later period (after 1991) than in the former period (9/22).

DNA Probes↗
PubMed1994

Analysis of oligosaccharides of human IgG from serum of leukemia patients.

The biantennary N-acetyllactosamine type oligosaccharide is attached to asparagine-297 of the human IgG heavy chain, which is an integral part of the tertiary structure of the Fc region, and is quite important in the role of IgG. Pyridylamination and analysis by HPLC can be performed more rapidly and simply than conventional carbohydrate analysis. We applied it to the analysis of the oligosaccharide structures of IgG from the serum of patients with leukemia, CLL and AML. The proportion of oligosaccharide from leukemia patients with a bisecting N-acetylglucosamine residue was almost equal to that of healthy individuals. However, the proportion of fucose and galactose residues differed. These data suggest that the analysis of the fucose and the terminal galactose residue of such oligosaccharides will be useful in the classification of leukemia.

Acetylglucosamine↗
PubMed1994

[Diploic epidermoid on the petrous bone: a case report].

An unusual case of a congenital petrous bone epidermoid which resulted in a sudden deafness is reported. The patient was a 25-year-old man who suddenly developed a right deafness and tinnitus. Neurological examination on admission revealed slight hearing disturbance in the high sound area. Plain craniogram showed a destructive bone lesion in the middle portion of the petrous bone on the right side. Bone-window CT scan disclosed a bony destructive mass in the petrous bone, and enlargement of the internal auditory canal. The mass lesion was almost isodense on plain CT scan and was not enhanced by contrast media. T1 weighted imaging of MRI demonstrated an isointense mass in the petrous bone, and T2 weighted imaging demonstrated hyperintensity. Gd-DTPA MRI revealed no enhancement. Angiogram did not reveal abnormal findings. Right lateral suboccipital craniectomy was performed to remove the posterior wall of the internal auditory canal. The tumor existed extradurally originating from the dipole of petrous bone. The tumor appeared pearly and fragile. The pathological examination of the specimen was diagnosed as epidermoid. The postoperative course was uneventful except for right hearing loss on the 4th postoperative day. Epidermoid arising in the middle portion of the petrous bone is quite rare, so this case was hereby reported with some references.

Adult↗
PubMed1993

A model of in vivo cell proliferation of adult T-cell leukemia.

We have made a model of in vivo cell proliferation of leukemic cells from adult T-cell leukemia (ATL) patients using severe combined immunodeficiency (SCID) mice. Peripheral blood mononuclear cells (PBMC) or lymph node cells (LNC) depleted of B cells and monocytes were intraperitoneally injected into SCID mice treated with antimurine interleukin-2 receptor (IL-2+) beta chain monoclonal antibody (MoAb)(TM-beta 1), followed by daily injection of human recombinant IL-2 until 60 days after cell injection. SCID mice injected with ATL cells from 6 of 8 ATL patients were found to have the tumor or leukemia 5 to 7 weeks after the inoculation of cells. Serum levels of soluble form of human IL-2R alpha chain (Tac) were markedly elevated in such mice. The cells recovered from the mice injected with leukemic cells from four different ATL patients had the same cell surface phenotype as that of original leukemic cells which were CD4+Tac+. Furthermore, we detected the same integration site of human T-cell leukemia virus type I (HTLV-I) provirus and the same rearrangement pattern of human T-cell receptor (TCR) beta chain gene as those of ATL cells by Southern blot hybridization, indicating that the cells proliferating in SCID mice were derived from the original ATL cell clone. Histologic examination showed that the pattern of the infiltration of ATL cells into various organs in SCID mice was similar to that of an ATL patient. Such a model of in vivo cell proliferation of ATL cells will be useful for the study of the mechanism of neoplastic cell proliferation and for the development of a new and effective treatment of ATL.

Aged↗
PubMed1993

The zitter rat: membranous abnormality in the Schwann cells of myelinated nerve fibers.

Ultrastructural alterations of the Schwann cells were chronologically examined in zitter and in control rats. The membranous abnormalities closely involving the nuclear membranes of the Schwann cells and mesaxons were constantly observed in the zitter rats. These structures consisted of scroll- or whirl-like unit membrane accumulations directly extending to the nuclear envelope. Occasionally, similar membranous structure were observed in association with the endoplasmic reticulum, lysosome or mitochondria in the cytoplasm of the Schwann cells. In the control rats, whirl-like membranous structures in the nuclear membranes of the Schwann cells were observed only intermittently at 1, 5 and at 7 days of age in the developing process. In conclusion, we postulate that the zitter rat, which is an established animal model for hypomyelination of the central nervous system (CNS), has some inherited abnormality related to the membrane biosynthesis and its regulation in Schwann cells as well as in oligodendrocytes.

Aging↗
PubMed1993

Age-related changes in the response of the rat urinary bladder to neurotransmitters.

The effect of age on the contractile response of the rat urinary bladder to various neurotransmitters was studied using in vitro detrusor strips isolated from female Wistar rats. The contractile responses to 8 neurotransmitters were determined for rat urinary bladders isolated from 3 age groups: 24, 16, and 6 months old. The results can be summarized as follows: 1) There was no age-dependent change in the maximum response to KCl. 2) The contractile response to norepinephrine, adenosine 5'-triphosphate (ATP), and serotonin increased with age. 3) The relaxation response to isoproterenol was significantly less in 24-month-old rats than in the other 2 age groups. 4) There were no age related changes in the responses to acetylcholine, prostaglandin F2 alpha, and angiotensin II. 5) Vasoactive intestinal polypeptide (VIP) failed to induce any response in the rat bladders of any group. 6) There were no significant differences in the ED50s for the 5 neurotransmitters among the 3 age groups. In summary, significant differences in the response to adrenergic, purinergic, and serotonergic stimulation were found as a function of age, whereas no age related changes in the response to cholinergic or generalized depolarization with KCl were found.

Aging↗
PubMed1993

Kinetic and circular dichroism studies of enzymes adsorbed on ultrafine silica particles.

Negatively charged ultrafine silica particles (average diameter 20 nm) were used as support materials for adsorption immobilization of porcine trypsin, horseradish peroxidase, and bovine catalase under various conditions, and the changes in the enzyme activities and the circular dichroism (CD) spectra of these enzymes upon adsorption were measured. Since the light scattering intensity of the ultrafine particles was very low, the activities and the CD spectra of the enzymes adsorbed on the particle surfaces could be measured. The enzymes adsorbed at pH around and above their isoelectric points (pI) showed high activities. On the other hand, the enzymes adsorbed at pHs below their pI had significantly diminished activities and showed large CD spectral changes upon adsorption. The extent of CD spectral changes in the enzymes upon adsorption correlated very closely with that of the activity reduction. Therefore, the conformational changes in enzymes upon adsorption are one of the important factors that reduce the activities of adsorbed enzymes. These results demonstrate that the ultrafine particles are not only a novel support for enzyme immobilization but also are helpful for the molecular understanding of the immobilized enzymes.

Adsorption↗
PubMed1993

Purification of fusion proteins using affinity microspheres in aqueous two-phase systems.

Affinity microspheres were prepared by immobilizing human gamma-globulin (H gamma Gb) onto carboxylated poly (styrene/acrylamide) latex particles [P(St/AAm)-H; average diameter 0.33 microns], which were prepared by emulsifier-free emulsion polymerization. H gamma GB was covalently immobilized onto the latex particles with high efficiency by the carbodiimide method. A fusion protein (ZZB1B2) of immunoglobulin G and albumin-binding domains (ZZ and B1B2, respectively) was expressed intracellularly and extracellularly in Escherichia coli and was purified by the affinity microspheres. In poly (ethylene glycol) (PEG)/potassium phosphate aqueous two-phase system, the affinity microspheres were partitioned into the PEG-rich top phase, while cells and cell debris of E. coli were displaced into the salt-rich bottom phase. Therefore, ZZB1B2 was directly purified from cell disintegrate or culture broth by combining the affinity microspheres with the aqueous two-phase partitioning, and its purity was almost the same as that purified by conventional affinity chromatography. Therefore, by this purification method, the primary purification process and the subsequent high resolution purification process are combined, and the number of purification steps can be reduced.

Chromatography, Affinity↗
PubMed1993

Esophageal cancer associated with multiple cancerous lesions: clinicopathologic comparisons between multiple primary and intramural metastatic lesions.

Detailed histopathological examination of serial blocks and subserial sections of the entire resected esophagus in 111 patients who underwent esophagectomy for esophageal squamous cell carcinoma revealed 38 associated cancerous lesions apart from the main tumors, in 33 patients (29.7%). These associated lesions were divided into multiple primary lesions (MPLs; 27 lesions in 23 patients) and intramural metastatic lesions (IMLs; 11 lesions in 10 patients). Thirteen and fourteen MPLs were distributed on the proximal and distal sides, respectively, of the main tumor with the same mean distance of 2.6 cm. Three and 8 IMLs were located on the proximal and distal sides, respectively, with mean distances of 3.4 cm and 4.6 cm. With respect to the histological depth of cancer invasion, MPLs were all confined within the submucosal layer (superficial cancer) while IMLs varied from the submucosa to the adventitia. Histological findings indicate that MPLs may be associated with a possible increased multicentric carcinogenic potential in the non-cancerous epithelium of the esophagus of patients who have had an antecedent esophageal cancer, and that IMLs are developed by intramural lymphatic spread from the primary esophageal cancer. These results emphasize the need for careful attention to the choice of margins during the surgical resection of the esophagus.

Aged↗