PubMed Health⌕ Search

Biomedical subjects

M Kondoh

Publications and source records attributed to M Kondoh.

At least 37 records · Page 2Linked to original sources
PubMed1999

A novel vaccine delivery system using immunopotentiating fusogenic liposomes.

We previously reported the preparation and characterization of fusogenic liposomes (FLs), which have two highly immunogenic glycoproteins of the Sendai virus on their surface. In this report, we investigated the capacity of FLs to enhance antigen-specific humoral immunity in mice. FLs function as a lymphocyte mitogen with high immunogenicity consistent with viral envelope proteins. Markedly increased levels of anti-ovalbumin (OVA) antibody were detected in serum from mice immunized with OVA encapsulated in FLs compared to sera from mice immunized with free OVA or OVA encapsulated in plain liposomes. An anti-OVA antibody response was not observed in mice immunized with OVA simply mixed with empty FLs. These results indicate that FLs function as a novel immunoadjuvant in inducing antigen-specific antibody production.

Adjuvants, Immunologic↗
PubMed1999

Apoptosis induction via microtubule disassembly by an antitumour compound, pironetin.

We reported previously that pironetin and its derivatives were potent inhibitors of cell cycle progression at the M-phase and showed antitumour activity against a murine tumour cell line, P388 leukaemia, transplanted in mice. In this paper, we investigated the mechanism of action of pironetins in antitumour activity and cell cycle arrest at the M-phase. As reported previously for murine leukaemia P388 cells, pironetin showed antitumour activity in a dose-dependent manner in the human leukaemia cell line HL-60. Since DNA fragmentation was observed in both P388 and HL-60 cells, the antitumour activity of pironetin is thought to be due to the induction of apoptosis. Pironetin also induced the rapid phosphorylation of Bcl-2 before formation of the DNA ladder in HL-60 cells, as seen with several tubulin binders. These results suggest that the antitumour activity of pironetin is due to apoptosis caused by the phosphorylation of Bcl-2, and that pironetin targets the microtubules. Pironetin and demethylpironetin exhibited reversible disruption of the cellular microtubule network in normal rat fibroblast 3Y1 cells. However, epoxypironetin, which contains epoxide instead of the double bond of pironetin, showed only weak activity. Since the concentrations that inhibit cell cycle progression at the M-phase were the same as those for disruption of the microtubule network, it was suggested that the mitotic arrest induced by pironetin was the result of the loss of the mitotic spindle. These compounds also inhibited the microtubule-associated protein-induced and glutamate-induced tubulin assembly in vitro. Pironetin inhibited the binding of [3H]vinblastine, but not that of [3H]colchicine, to tubulin, and the Kd values revealed that the affinity of pironetin for tubulin is stronger than that of vinblastine. These results suggest that pironetins are novel antitumour agents which inhibit microtubule assembly.

Animals↗
PubMed1999

Fusion of sendai virus with liposome depends on only F protein, but not HN protein.

Sendai virus is able to fuse with liposomes even without virus receptors. To determine the roles of envelope protein, hemagglutinin-neuraminidase (HN) and fusion (F) protein, in Sendai virus-liposome fusion, we treated the virus with proteases and examined its fusion with liposomes and the conditions of HN and F protein. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis and western blotting analysis showed that the virus treated with 150 units/ml of trypsin, which inactivated selectively hemolysis activity, maintained intact HN, F and partially digested F (32 kDa) protein, while virus treated with 15,000 units/ml of trypsin, which inactivated both hemolysis and neuraminidase activity, had only a 15-kDa digested HN protein and completely digested F protein. The former fused with liposomes, but the latter did not. In the virus treated with chymotrypsin, which lost both hemolysis and neuraminidase activity, F protein was intact, while HN protein was degraded to 15 kDa; in this case the virus fused with liposomes. As the virus with 15-kDa HN protein fused with liposomes and that with 20-kDa protein did not, HN protein does not appear to play any role in virus-liposome fusion. The virus that fused with liposomes had intact F protein. We conclude that Sendai virus-liposome fusion is strongly dependent on the presence of intact F protein, but not HN protein.

Blotting, Western↗
PubMed1999

A case of multiple sebaceous epithelioma: analysis of microsatellite instability.

Sebaceous gland tumor is a rare disease that is a sign of Muir-Torre syndrome, an autosomal, dominantly inherited genodermatosis characterized by the presence of at least one sebaceous gland tumor and a minimum of one internal malignancy. Recent studies have indicated that defective DNA mismatch repair occurs in Muir-Torre syndrome. Cutaneous lesions may occur before diagnosis of the internal cancer. We describe a 64-year-old male patient with multiple sebaceous epitheliomas with no evident internal malignancy. Microsatellite instability, determined by examining dinucleotide CA repeats at the microsatellite loci, was observed in DNA from one sebaceous epithelioma but not from the other two sebaceous epitheliomas or from one basal cell epithelioma with sebaceous differentiation, suggesting that this condition is unlikely to be due to germ-line mutation of mismatch repair genes.

Adenocarcinoma, Sebaceous↗
PubMed1999

Muscle hypertrophy in rats fed on a buckwheat protein extract.

Growing rats were examined for the influence of a buckwheat protein diet on muscle weight and protein. In experiment 1, the rats were fed on a diet containing either casein or a buckwheat protein extract (BWPE) as the protein source (10%, 20% or 30%) for 5 wk. The relative weights (g per kg of body wt) of the gastrocnemius, plantaris and soleus muscles were higher in the BWPE-fed animals than in the casein-fed ones, but were unaffected by the dietary level of protein. These differences were not associated with growth. In experiment 2, the rats were fed on either a casein or BWPE diet at the 20% protein level for 5 wk. BWPE intake significantly elevated the gastrocnemius muscle weight, carcass protein and water, and reduced carcass fat. These results demonstrate that BWPE consumption causes muscle hypertrophy, elevates carcass protein and water, and reduces body fat.

Amino Acids↗
PubMed1999

[A case of arteriovenous fistula of the lung].

A 29-year-old male was admitted to our hospital for further evaluation of left sided paresis, cyanosis, clubbing finger. The laboratory data revealed polycythemia and hypoxemia. Cerebralarteriogram showed right middle cerebral artery occulusion. Cardiofunctional test showed atrial fibrillation, lower left ventricular function. Cardiac catheterization, pulmonary arteriography and three dimensions CT were performed. Right to left shunt rate was 20.4%. A single large pulmonary arteriovenous fistura with a feeding artery (A10) and a draining vein (V10) was found clearly. In this cases, arteriovenous fistula was large, blood flow was thought to be rapid. We thought transcatheter embolization was not useful. And we performed right lower lobectomy. Postoperative course was not eventful. Cyanosis disappeared, clubbing finger was cured.

Adult↗
PubMed1999

[A case of pulmonary dirofilariasis].

A 58-year-old man was admitted to our hospital for detailed examination of continuous cough. On a chest X-ray film, abnormal shadow was detected in the right lower lung field. Preoperative examination findings didn't lead to a definitive diagnosis. Under thoracoscopy partial resection of the lung was performed to rule out a malignant lesion. Intraoperative pathologic finding revealed a granulomatous lesion. And, final pathological diagnosis showed to be a pulmonary dirofilariasis. His postoperative course was not eventful. On 20 th day he discharged postoperatively. Now, under the Pet-boom the disease has been reported increasingly. But it is difficult to find the disease preoperatively. So, it is real to be operated for differentiate from a malignant lesion. Recently in many cases open lung biopsy, has been undergone with less invasive procedure such as thoracoscopy and VATS. It will be mainstream in future.

Dirofilariasis↗
PubMed1999

[Influence of PEEP on left ventricular diastolic function].

We investigated the influence of PEEP on left ventricular diastolic function using the pressure-volume loops by employing a micromanometer catheter and a conductance catheter placed in the left ventricle of the eight mongrel dogs. Time constant of diastolic interval was shortened under the condition of 15 cmH2O of PEEP compared with the control value (PEEP 0 cmH2O) and the diastolic stiffness constant was prolonged under 15 cmH2O of PEEP. It was considered that the shortened time constant of diastolic interval was due to the decrease of preload. The prolongation of diastolic stiffness constant was possibly due to compression of the heart by increased intrapleural pressure. We conclude that decreased compliance of left ventricle caused by PEEP might impair the left ventricular function.

Animals↗
PubMed1998

Tryprostatin A, a specific and novel inhibitor of microtubule assembly.

We have investigated the cell cycle inhibition mechanism and primary target of tryprostatin A (TPS-A) purified from Aspergillus fumigatus. TPS-A inhibited cell cycle progression of asynchronously cultured 3Y1 cells in the M phase in a dose- and time-dependent manner. In contrast, TPS-B (the demethoxy analogue of TPS-A) showed cell-cycle non-specific inhibition on cell growth even though it inhibited cell growth at lower concentrations than TPS-A. TPS-A treatment induced the reversible disruption of the cytoplasmic microtubules of 3Y1 cells as observed by indirect immunofluorescence microscopy in the range of concentrations that specifically inhibited M-phase progression. TPS-A inhibited the assembly in vitro of microtubules purified from bovine brains (40% inhibition at 250 microM); however, there was little or no effect on the self-assembly of purified tubulin when polymerization was induced by glutamate even at 250 microM TPS-A. TPS-A did not inhibit assembly promoted by taxol or by digestion of the C-terminal domain of tubulin. However, TPS-A blocked the tubulin assembly induced by inducers interacting with the C-terminal domain, microtubule-associated protein 2 (MAP2), tau and poly-(l-lysine). These results indicate that TPS-A is a novel inhibitor of MAP-dependent microtubule assembly and, through the disruption of the microtubule spindle, specifically inhibits cell cycle progression at the M phase.

Animals↗
PubMed1998

Cell cycle arrest and antitumor activity of pironetin and its derivatives.

The biological effects of pironetin and its derivatives on cell cycle progression and antitumor activity were studied. At 10-20 ng/ml, both pironetin and its demethyl derivative, NK10958P completely inhibited the cell proliferation of 3Y1 cells, however, epoxypironetin showed only a weak inhibitory activity. The cell cycle analysis revealed that these compounds arrested the cell cycle progression at the M-phase in a dose-dependent manner. These antiproliferative effects of pironetin were also observed in the range 5-25 ng/ml with several tumor cell lines. In CDF1-SLC mice bearing P388 leukemia cells, the intraperitoneal administration of 6.3 mg/kg pironetin over a 5-day period showed a moderate antitumor effect (T/C, 128%). As the chemical structure of pironetin is different from other M-phase inhibitors such as colchicine or vinblastine, pironetin will be the lead compound for a potential new antitumor drug.

Animals↗
PubMed1998

Confocal laser scanning and electron-microscopic analyses of the relationship between VIP-like and GnRH-like-immunoreactive neurons in the lateral septal-preoptic area of the pigeon.

The lateral septum and the preoptic area of birds comprise neurons immunoreactive (ir) for vasoactive intestinal polypeptide (VIP) and gonadotropin-releasing hormone (GnRH). By use of immunohistochemical single- and double-labeling techniques, we have investigated the distribution and the connections of these two types of peptidergic neurons in the lateral septal-preoptic area of the pigeon at both the light- and electron-microscopic levels. An accumulation of VIP-like-ir neurons, some of which are cerebrospinal fluid-contacting neurons, is found in the area adjacent to the ventromedial walls of the lateral ventricles in the lateral septum corresponding to the medial part of the lateral septal organ. VIP-like-ir terminals are scattered throughout the lateral septal-preoptic area, which also contains GnRH-like-ir cell bodies. The number of GnRH-like-ir cell bodies in the lateral septum is smaller than that of the VIP-like-ir neurons. GnRH-like-ir cells have a simple bipolar or multipolar shape and a beaded axon that emerges from the soma or one of the proximal dendrites. Confocal laser scanning microscopy has shown VIP-like-ir terminals in close apposition to GnRH-like-ir cell bodies in the lateral septal-preoptic area. Furthermore, the electron-microscopic double-immunolabeling has revealed synaptic contacts between VIP-like-ir axon terminals and GnRH-like-ir cell bodies or dendrites. These contacts, however, do not show synaptic specializations. The present results suggest that functional interactions take place between VIP and GnRH neurons in the lateral septal-preoptic area of the pigeon and that these interactions are involved in mediating photoperiodic responses.

Animals↗
PubMed1998

Effects of FK506 on experimental membranous glomerulonephritis induced by cationized bovine serum albumin in rats.

BACKGROUND: There have been no reports on the effect of FK5 06, a new immunosuppressive agent, on experimental membranous glomerulonephritis (MN) induced by an exogenous antigen. Therefore we investigated the effects of FK506 on MN induced by cationized bovine serum albumin (C-BSA) in rats. METHODS: Two weeks after the rats were immunized with 1 mg of C-BSA and Freund's complete adjuvant, they received intravenous injections of 3 mg/kg of C-BSA 3 times weekly for 4 weeks. Rats were divided into four groups: group A (n = 5) received intramuscular injections of 3 mg/kg of FK506 daily for 5 days beginning 2 days before the first immunization; group B (n =4) received 1 mg/kg of FK506 daily for 2 weeks beginning 2 weeks after the first immunization; and group C (n =4) received 1 mg/kg of FK506 daily for 2 weeks beginning 4 weeks after the first immunization. Group D (n = 5) received no FK506 and served as the control group. Rats were sacrificed 8 weeks after the first immunization. RESULTS: Administration of FK506 in the preimmunization stage almost completely suppressed the development of MN in group A. Histological findings in groups B and C were similar to those in group D, the control group. However, urinary protein excretion was significantly lower in group B (24+/-46 mg/day) and C (220+/-44 mg/day) than in group D (330+/-61 mg/day). Expression of intracellular adhesion molecule-1 in glomeruli and the number of leukocyte functioning-associated molecules-1 were significantly decreased in groups A, B, and C compared with the control group. Administration of FK506 was not associated with any significant side-effects or histological abnormalities. The whole-blood trough levels of FK506 in groups B and C were 9.1 ng/ml and 9.2 ng/ml respectively. CONCLUSIONS: The efficacy of FK506 was significantly increased when the drug was administered in the early phase of immunization in this model. The present study suggests that FK506 may be useful in patients with intractable nephrotic syndrome such as MN.

Animals↗
PubMed1998

Pyodermia chronica glutealis complicated by acromegalic gigantism.

We report a case of pyodermia chronica glutealis complicated by acromegalic gigantism associated with hyperprolactinemia. The serum prolactin, growth hormone, adrenocorticotropic hormone, and 11-deoxycortisol levels were elevated, but the estradiol and dehydroepiandrosterone-sulphate levels were within normal limits. However, the testosterone level was very low. Histopathologically, we found sinus tracts and scarring in a specimen from the buttocks. We could not immunohistochemically detect clear androgen, growth hormone, or prolactin receptors at any site. The patient was a man with a height of 197 cm and weight of 140 kg, he had clinical features of active acromegaly such as excessive sweating and increased thickness of soft tissue. He was also diagnosed with diabetes mellitus. Under such conditions, bacteria could easily grow and lesions might have been aggravated by the heavy pressure from his weight, a possible causes of his pyodermia chronica glutealis.

Acromegaly↗
PubMed1998

Transmural myocardial infarction caused by thromboembolism associated with mitral insufficiency in a dog.

A 10-year-old dog, which had been treated for mitral insufficiency, died suddenly. Transmural myocardial infarction secondary to thromboembolic occlusion of the subsinuosal interventricular branch of the left circumflex artery was noted in the posterior lower half of the left ventricular wall, involving the interventricular septum and a part of right ventricular wall. The mitral valve leaflets were markedly thickened (valvular endocardiosis). These were a patchy area of jet lesion and several mural thrombi on the left-atrial endocardium. The embolus in the subsinuosal interventricular branch was composed of mostly platelets and fibrin, showing the same histologic features as those of the mural thrombi on the left-atrial endocardium. From these findings, it was concluded that dislodgement of part of the mural thrombi on the left-atrial endocardium caused thromboembolism of the subsinuosal interventricular branch.

Animals↗