Biomedical subjects

T Ishida

Publications and source records attributed to T Ishida.

At least 433 records · Page 24Linked to original sources

PubMed1997

Perforin-like immunoreactivity in four cases of lymphoma of large granular lymphocytes in the cat.

Tumors composed of discrete round cells with large eosinophilic granules in their cytoplasm were observed in four cats. These cats were presented with severe gastrointestinal signs, including anorexia, vomiting, and diarrhea. The exploratory laparotomy in two cats and necropsy in the other two revealed thickening and perforation of the intestinal walls, enlargement of the mesenteric, ileocolic, and/or colic lymph nodes, and splenomegaly. Histologically, there was severe and disseminated infiltration of the tumor cells in the affected organs. In the two cats necropsied, the spleen and the jejunal mucosa appeared to be the primary organs involved. The tumor cells of all the cats showed the pore-forming protein (perforin)-like immunoreactivity unique to the cytotoxic lymphocytes but failed to show histamine immunoreactivity. These results indicate that the tumor cells were derived from large granular lymphocytes and that perforinlike immunoreactivity may be a useful marker for histologic diagnosis of feline large granular lymphoma.

Animals↗

PubMed1997

Effect of serum components from different species on destabilizing hydrogenated phosphatidylcholine-based liposomes.

It is accepted that some serum components play important roles in enhancing liposome permeability and in facilitating rapid liposome uptake by the mononuclear phagocytic system. In this study we systematically investigated the influence of serum components from different species on complement-mediated immune damage to hydrogenated phosphatidylcholine (HEPC)-based liposomes. Our results demonstrated that when liposomes were incubated with fresh serum from rats or bovines, there was obvious leakage of 5(6)-carboxyfluorescein (CF) from the liposome. However, when liposomes were incubated with fresh serum from humans, rabbits, guinea pigs, mice, and dogs, almost no pronounced leakage from the liposome was observed. These results indicate that the variability of damage to a liposome corresponds to the variability of the animal species from which the serum comes. In addition, leakage of CF from liposomes was completely inhibited by heating at 56 degrees C for 30 min or by treatment with EDTA. However, such leakage was not blocked by treatment with EGTA/Mg2+, suggesting that the mechanism of lysis of liposomes is due to complement activation via the alternative pathway rather than via the classical pathway. Studies on reconstitution and compatibility further confirm that some serum factors (complement activating factors, CAFs) induce the activation of the complement system, ultimately leading to the lysis of the liposomes. However, CAF from different animal species exhibited corresponding species differences. Meanwhile, under the condition of heating and dialysis experiments, it is obvious that the CAF is susceptible to heat and the dialysed serum sustains biological activity to destabilize liposome following dialysis against a buffer with Ca2+ and Mg2+, indicating that the CAF is not a type of low-molecular weight material but a serum protein.

Animals↗

PubMed1997

Alteration of T-cell subsets in the lymph nodes from cats infected with feline immunodeficiency virus.

Alterations of T-cell subsets in the lymph nodes from FIV-infected cats in various clinical disease stages were examined histologically. In the early stage of infection (AP stage), follicular hyperplasia accompanied by expansion of the paracortical area was observed. Follicular involution and depletion with reduced paracortical area was observed in the ARC and AIDS stage nodes. The maximum section area of the entire popliteal lymph node was expanded significantly in the AP nodes. The paracortical area expanded in the AP nodes and decreased in the ARC and AIDS stage nodes. The cell density in the paracortical area in the AP nodes did not show a significant increase, while there was a significant reduction in the ARC and AIDS stage nodes. The lymph node CD4/CD8 ratio in the AP and ARC stages significantly decreased as compared with that of uninfected control cats, but conversion of the ratio was not seen. The estimated total numbers of CD4+ and CD8+ cells in the maximum section were increased in the AP stage but significantly decreased in the ARC and AIDS stages. Our study indicated that the lymphocyte depletion in the terminal ARC and AIDS stages of FIV infection was associated with both CD4+ cells and CD8+ cells. Findings obtained in this study might provide useful information for studying the pathophysiology of FIV infection.

AIDS-Related Complex↗

PubMed1997

An improved canine model of subarachnoid hemorrhage using intrathecal indwelling catheters.

In the present study, the feasibility of intrathecal indwelling catheters in the preparation of a repeated subarachnoid hemorrhage (SAH) model in dogs, as well as chronic intrathecal administration of therapeutic agents against the ensuing cerebral vasospasm was examined. Briefly, through a small suboccipital incision, two catheters were introduced into the subarachnoid space so that their tips were positioned in the prepontine cistern. One was used to induce SAH by infusing autologous blood, and the other to administer pharmacological agents (saline and/or saline containing a dye in this study) by means of an osmotic pump. The occurrence of cerebral vasospasm was followed by angiography via the catheter placed in the vertebral artery. The obtained results show: i) the injected blood effectively formed a subarachnoid clot in the prepontine cistern, invariably leading to the occurrence of severe cerebral vasospasm of the basilar artery; ii) the fluid injected by the osmotic pump was evenly distributed in the cisterns around the brain stem; iii) on post mortem pathological examination, no injury of the brain or the major arteries ascribable to the placement of catheters was found. Therefore, the present model is considered to be useful for both the investigation of pathophysiology and therapy of cerebral vasospasm following SAH, to be more favorable from the standpoint of animal protection, and more convenient and reliable than those used until now.

Angiography↗

PubMed1997

Mental deterioration in childhood epilepsy.

Mental retardation is detected in 20-30% of children with epilepsy at hospitals specializing in treatment of childhood epilepsy. However, the incidence of mental deterioration in childhood epilepsy is not high. In this study, mental deterioration was found in 52 (1.8%) of the 2,880 children with epilepsy at Okayama University Hospital. The patients showing mental deterioration mostly suffered from specific epileptic syndromes, such as West syndrome, Lennox-Gastaut syndrome, severe myoclonic epilepsy in infancy and epilepsy with continuous spike-waves during slow wave sleep. These types of epilepsy show generalized electroencephalographic (EEG) abnormalities. It is presumed that mental deterioration is caused by the total effects of prolonged diffuse EEG abnormalities and the age of the patients. Antiepileptic drugs exert a relatively minor effect on mental deterioration.

Adolescent↗

PubMed1997

The effect of somatostatin analogue on glucose homeostasis in conscious dogs.

Our aim was to clarify the effect of a somatostatin analogue (octreotide) on glucose flux in conscious dogs. We monitored the effects with catheters in the portal vein, hepatic vein and femoral artery and Doppler flow probes on the portal vein and hepatic artery before and after oral glucose administration. A significant increase of portal vein plasma flow after oral glucose was completely suppressed by both 4 and 1 micrograms/kg octreotide. All doses of octreotide (4, 1 and 0.1 microgram/kg) suppressed the glucose-induced increment of arterial glucose by dose response. Only 4 micrograms/kg of octreotide slightly but significantly suppressed hepatic glucose output. Marked suppression and delayed glucose absorption by the intestine was observed after 4 micrograms/kg of octreotide. One and 0.1 microgram/kg octreotide also suppressed glucose absorption without delayed absorption. Total amounts of absorbed glucose during 3h after oral glucose were 24 +/- 11% with 4 micrograms/kg of octreotide, 37 +/- 16% with 1 microgram/kg of octreotide, and 48 +/- 8% with 0.1 microgram/ kg of octreotide, all of which were significantly less than that of the control (73 +/- 8%). Using 4 micrograms/kg of octreotide treatment, the liver took up only 5 +/- 4% of the absorbed glucose, while the liver took up 35 +/- 6% and 43 +/- 9% of the absorbed glucose with 1 and 0.1 microgram/kg of octreotide. These latter values were similar to that of the control value of 34 +/- 4%. In conclusion, we found that octreotide administered before oral glucose had a remarkable stabilizing effect on postprandial glycemic surges. Both the direct inhibitory effect of octreotide on portal vein plasma flow and impaired glucose absorption would contribute to this decreased postprandial hyperglycemia, while its suppressive effect on other hormones, such as insulin and glucagon, did not seem to influence the reduction of hyperglycemia.

Animals↗

PubMed1997

Discitis, infectious arthritis, and bacterial meningitis in a patient with pancreatic diabetes.

A 63-year-old woman with pancreatic diabetes after a total pancreatectomy and splenectomy developed discitis of the L2/3 intervertebral disk. Rapidly she also developed infectious arthritis of the left knee joint and bacterial meningitis. Aspirate from the left knee contained Enterococcus faecalis. The diagnosis of discitis is generally difficult in the initial period of disease, and patients with diabetes or splenectomy are susceptible to rapid progression of the infection. Early diagnosis of discitis using magnetic resonance imaging of the spine and treatment with antibiotics might have altered her clinical course.

Arthritis, Infectious↗

PubMed1997

[A case of adenocarcinoma of the reconstructed bladder following ileocystoplasty].

We experienced a case of adenocarcinoma occurring in the reconstructed bladder 38 years after ileocystoplasty. The patient was a 48-year-old woman, who had undergone ileocystoplasty and left nephrectomy at the age of 10 for the treatment of tuberculous contracted bladder and left renal tuberculosis. She had often suffered from right pyelonephritis following the operation. She visited our hospital for work-up of a high value of carcinoembryonic antigen (CEA). The findings of cystoscopy, cystogram and urine cytology showed a malignant tumor of the reconstructed bladder. Then, we performed total cystectomy and right ureterostomy. The histopathological examination showed that the tumor was an adenocarcinoma which developed mainly from the ileal segment of the reconstructed bladder.

Adenocarcinoma↗

PubMed1997

[gamma-Glutamylcysteine synthetase and chemosensitivity].

The gene transfectant with gamma-glutamylcysteine synthetase (gamma-GCS) gene, a rate limiting enzyme in GSH biosynthesis, exerted increased GSH content and ATP-dependent glutathione S-conjugate export pump (GS-X pump) decreased intracellular platinum and sensitivity against cisplatin. It is suggested that GS-X pump expression is related to cellular GSH metabolism and involved in cisplatin resistance. gamma-GCS transfectant also showed the resistance to MMC with the decreased DNA-MMC adduct. On the other hand, a MMC derivative, KW-2149, which is activated by thiol molecule, exhibited high cytotoxicity against the transfectant with an equal amount of DNA-MMC adduct compared with parental cells. It is suggested that KW-2149 could circumvent the GSH-mediated drug resistance.

3T3 Cells↗

PubMed1997

Hepatocellular carcinoma patients showing long-term complete responses to chemoembolization.

The objective was to evaluate hepatocellular carcinoma (HCC) patients showing a long-term complete response (CR) to chemoembolization. We defined the criteria of CR as normalized tumor marker, no enhanced tumor in diagnostic images, and no tumor cells found at autopsy. Five HCC patients showing long-term CR to chemoembolization were evaluated. The CR period ranged from 3.5 to 7 years (mean, 5.7 years). The survival period ranged from 3.5 to 9 years (mean, 6.7 years). Four cases (80%) were stage IV according to the TNM classification due to a portal tumor thrombus. The liver function was rated as Child's A in four cases (80%). Long-term CR to chemoembolization can be achieved even in some advanced HCC cases with a tumor thrombus. We speculate that the good antitumor effect is brought about by the stagnation of both the arterial and portal blood flows to the HCC. Good liver function is also considered to be an important factor for long-term CR and a long survival period. If the liver function is good, advanced HCC with a portal tumor thrombus should be treated aggressively with chemoembolization.

Aged↗

PubMed1997

Prevalence and molecular epidemiology of GB virus C/hepatitis G virus infection in Mongolia.

We studied the prevalence of GB virus C/hepatitis G virus (GBV-C/HGV) infection among 112 patients with liver disease and 121 blood donors in Ulaanbaatar, Mongolia. Reverse transcription and polymerase chain reaction were employed to detect GBV-C/HGV RNA using the specific primers derived from the 5'-untranslated region (5'-UTR) of the GBV-C/HGV genome. Nucleotide sequences of all positive samples for GBV-C/HGV RNA were determined. The sequences were analyzed by a molecular evolutionary method. Twenty-five (10.7%) of 233 people were positive for GBV-C/HGV RNA. Eight (6.6%), 11 (9.1%), and 30 (24.8%) blood donors were positive for GBV-C/HGV RNA, HBsAg, and anti-HCV, respectively, although 17 (15.2%), 65 (58.0%), and 64 (54.5%) patients with liver disease were positive for each viral marker. The prevalences of GBV-C/HGV RNA, HBV, and HCV in the patients were significantly higher than those in blood donors (P < 0.05). There was no significant difference in the prevalence of anti-HCV among people with and without GBV-C/HGV RNA, while the prevalence of HBsAg among people with GBV-C/HGV RNA was significantly higher than among those without GBV-C/HGV RNA (P < 0.05). The molecular evolutionary tree showed that GBV-C/HGV was a heterogeneous virus and all strains could be divided into 2 types. One is the same phylogenetic type as HGV, and the other is a new type that is different from GBV-C and HGV.

Adult↗

PubMed1997

[Production of antibody against cytosolic 54 kDa protein in rat liver--evidence of the significant induction by a highly toxic coplanar polychlorinated biphenyl].

We have reported that a 54 kDa protein in rat liver cytosol is highly inducible by treatment with 3,3',4,4',5-pentachlorobiphenyl (PenCB) or 3-methylcholanthrene (MC) using SDS-polyacrylamide gel electrophoresis. Internal amino acid sequences of this protein in the rat liver were highly homologous to those of selenium binding protein (SeBP) or acetaminophen binding protein (APBP) in mouse liver cytosol. In this paper, the purification and characterization of this protein were demonstrated. MC was given at a dose of 20 mg/kg for 3 consecutive days. The liver cytosolic 54 kDa protein was purified twice from the MC-treated male Wistar rats by Rotofore Cell procedure to apparent single on SDS-polyacrylamide gel electrophoresis, and the rabbit antiserum against this protein was obtained. Male Wistar rats were given PenCB in corn oil at a single dose of 25 mg/kg i.p. The liver cytosol was prepared on the 5th day after the treatment and subjected to immunoblot analysis. The 54 kDa protein was markedly induced in the liver cytosol of PenCB-treated rats. Immunoblot analysis after two-dimensional gel electrophoresis suggested that there could be isoforms of 54 kDa protein. The induction of the 54 kDa protein with PenCB was assumed to be mediated through Ah-receptor. The physiological role of the 54 kDa protein was discussed together with SeBP and APBP, the role of which has not yet been elucidated.

Animals↗

PubMed1997

Oncogenic transformation and inhibition of adipocytic conversion of preadipocytes by TLS/FUS-CHOP type II chimeric protein.

Myxoid liposarcomas are characterized by t(12; 16)(q13;p11) translocation and expression of TLS/ FUS-CHOP chimeric transcripts (types I to III). Among these, the type II transcript is expressed in the majority of cases of myxoid and round cell liposarcoma. To investigate the function of the type II chimeric protein, we obtained stable transformants of ST-13, a murine preadipocytic cell line, which express TLS/FUS-CHOP type II protein (ST-TC) or CHOP protein (ST-C) as well as vector-transfected controls (ST-V). ST-TC and ST-C cells showed almost complete or partial resistance to adipogenic conversion by insulin and thiazolidinedione, respectively. Induction by adipogenic stimulation of the adipocytic genes such as C/EBP alpha, aP2, and adipsin was almost totally suppressed in the ST-TC cells, whereas in ST-C cells C/EBP alpha alone was induced without induction of aP2 and adipsin. Transcriptional suppression of the C/EBP alpha gene in ST-TC cells was suggested by the results of chloramphenicol acetyltransferase (CAT) assay showing a significantly lower C/EBP alpha promoter activity compared with findings in ST-C and ST-V cells. Failure to rescue adipogenic conversion by ectopic expression of C/EBP alpha in ST-TC cells suggested a functional impairment of C/EBP alpha to induce expression of downstream genes. TLS/FUS-CHOP type II protein showed transforming activity, as evidenced by loss of contact inhibition of growth, anchorage-independent growth in soft agar, and tumor formation in nude mice, showing typical histological features of myxoid liposarcoma seen in humans. These findings suggest important roles for TLS/FUS-CHOP type II protein in the oncogenesis of myxoid liposarcoma.

Adipocytes↗

PubMed1997

Direct measurement of endosomal pH in living cells of the rat yolk sac epithelium by laser confocal microscopy.

Endocytosis of dual-fluorescent dextran by epithelial cells was observed in the perfused rat yolk sac using a confocal laser scanning microscope. Endosomal pH was quantified from confocal images using a dual-fluorescence ratiometry technique. Changes in endosomal pH were followed over time up to 32 min with and without Brefeldin A treatment. After 4 min of endocytosis without Brefeldin A, endosomes had a pH of 6.1 +/- 0.3. After 16 min and 32 min, their pH levels varied widely from 4.0 to 6.6. When Brefeldin A (10 microM) was added to the perfusion medium, endosomal pH remained fairly stable in the range of 6.0 to 6.2 from 4 min to 32 min. The corresponding endosomal structures were examined by electron microscopy after endocytic labeling with horseradish peroxidase. After 4 min, small endocytic vesicles and large endosomal vacuoles with tubular extensions were labeled. After 16 min and 32 min, multivesicular bodies and dense lysosomal structures were progressively labeled, but their labeling was almost undetectable after Brefeldin A treatment. These results suggested that the pH within the sorting compartment of early endosomes is 6.1 +/- 0.3. This is the first quantitative measurement of pH within sorting endosomes in intact cells of the living yolk sac epithelium.

Animals↗

PubMed1997

Serotyping of Duffy blood group in several Thai ethnic groups.

Duffy blood groups were serologically investigated in 434 individuals from Black Lahu (N = 54), Shan (N = 62), Lisu (N = 74), Red Karen (N = 112), White Karen (N = 102) and Manni (N = 30) in Thailand. High frequency of Fya (0.917-1.0) which is comparable with other Mongoloid populations was observed. The presence of weak-Fya antigen was detected in eight individuals of northern ethnic groups.

Adult↗

PubMed1997

[Prevailing conditions and problems with blood transfusion tests as seen after analysis of Osaka Medical Association Survey].

We have analysed the results of the 1996 Osaka Medical Association Clinical Examination Quality Control survey. The number of participating clinical laboratories was 257 for ABO blood group system, 255 for Rh (D) antigen, and 250 for crossmatching. Five (5) clinical laboratories (1.9%) determined the ABO blood group by the antigens on red blood cells test only, and three (3) clinical laboratories (1.2%) showed errors when using antibodies in serum test. On the Rh(D) antigen tests, fifteen (15) clinical laboratories (5.9%) showed negative results without carrying out an antiglobulin test. Three (3) clinical laboratories (1.2%) were unable to detect the anti Dib antibody which showed 1:256 titerates using the antiglobulin test method. Moreover, it was apparent that thirty-four (34) clinical laboratories (13.6%) had problems with the test standards and other technical points, and further, two (2) clinical laboratories (0.8%) reported contradictory results due to confusing blood samples of donors and patients to be transfused. As a result, we consider it very important for preventing blood transfusion accidents that any technician carrying out blood transfusion tests makes correct decisions and determinations based on accurately performed test methods, and that a manual be prepared to avoid technical and administrative errors and that this manual be followed to the letter.

ABO Blood-Group System↗

PubMed1997

[Local control of hepatic malignant tumors by percutaneous microwave].

We investigated the effects of percutaneous microwave coagulation under general anesthesia in the local control of hepatic malignant tumors. Coagulation at 60 W was done for normal liver of living swine using a percutaneous electrode. Wide-range coagulation at the tip of an electrode, 3 mm in diameter, was conducted. Clinically, echo-guided percutaneous microwave tumor coagulation was done for a total of 11 lesions in 5 patients with hepatocellular carcinoma and 4 with metastatic tumors in the liver under general anesthesia. Coagulation at 60 W of the liver of living swine for 1.5 and 10 min, using a percutaneous electrode, produced a maximal coagulation of 10, 20 and 30 mm, respectively. The trial electrode permitted coagulation almost at the tip of the electrode only. Percutaneous microwave coagulation of 11 lesions of the clinical cases resulted in complete coagulation in 7 lesions and incomplete coagulation in 4. The lesions showing complete coagulation were all less than 23 mm.

Animals↗

PubMed1997

[Complication of reservoir hepatic artery infusion chemotherapy and additional treatments].

In 54 patients who underwent hepatic artery infusion chemotherapy for hepatic tumors at our hospital between January 1990 and December 1996, we investigated the complications of this therapy and the therapeutic techniques following its discontinuation. The arterial infusion was discontinued in 36 of the 54 patients; 13 due to death (mean survival period: 15.7 months), and 23 in whom occlusion of the reservoir, etc. made it impossible to use arterial infusion (mean period of use: 13.8 months), and the minimum duration of use was 41 days and maximum duration of use 992 days. The most common complication of the reservoir hepatic artery infusion was reservoir occlusion (14.8%). Another serious complication was reservoir deviation outside the blood vessel in two patients; deviation in to the gastric lumen in one case and intraperitoneal deviation in the other. Four hepatocellular carcinoma patients, in whom it became impossible to use the reservoir due to its occlusion, underwent re-hepatectomy. Three of them survived for more than two years following supplemental local therapy, including subarterial injection, TAE, PEIT, microwave tumor coagulation (MTC). Of four patients with colon cancer metastasizing to the liver, one could undergo re-hepatectomy, one received subarterial injection, and two have survived without relapse. Two of three patients with breast cancer underwent systemic chemotherapy and endocrine therapy successfully, while the third one underwent subarterial injection and TAE, and is still under observation. Hepatic artery infusion should sometimes be discontinued owing to complications caused by various factors. Even if it becomes impossible to use the reservoir, local therapeutic techniques, including re-hepatectomy, TAE, PEIT, MTC, etc., may be performed in some patients. These findings suggest that it is necessary to review the interdisciplinary treatment so as to be appropriate to the primary disease.

Aged↗