Biomedical subjects

T Sako

Publications and source records attributed to T Sako.

At least 37 records · Page 2Linked to original sources

PubMed2002

Changes in activities of enzymes related to energy metabolism in peripheral leukocytes of diabetic dogs with glycemic control by intensive insulin treatment.

Changes in plasma glucose, immunoreactive insulin (IRI), and free fatty acids (FFA) concentrations and activities of enzymes related to energy metabolism in peripheral leukocytes were measured in type 1 diabetic dogs induced by streptozotocin administration before and after intensive insulin treatments. Before the insulin treatment, the plasma glucose concentrations were over 16.7 mmol/L and the activities of enzymes remarkably decreased in leukocytes of the diabetic dogs. In particular, malate dehydrogenase (MDH) activities decreased significantly. After glycemic control was achieved by insulin treatment, the plasma glucose concentrations were maintained between 6.8 and 7.7 mmol/L and the activities of enzymes restored to those in the control dogs. The changes in ML ratio (cytosolic MDH/lactate dehydrogenase specific activity ratio) reflected faithfully to metabolic conditions of animals and were considered to be a useful parameter to evaluate glycemic control and the effect of injected insulin in the diabetic dogs.

Animals↗

PubMed2002

Detection of matrix metalloproteinases in canine mammary tumours: analysis by immunohistochemistry and zymography.

Expression of matrix metalloproteinases (MMPs) was examined immunohistochemically (MMP-9 and -2) and by gelatin zymography (MMP-9) in 12 benign and 12 malignant canine mammary tumours. In nine of 12 benign tumours, weak expression of MMP-9 was demonstrated immunohistochemically in the cytoplasm of neoplastic cells. In the remaining three benign tumours (mixed or complex) MMP-9 expression was observed in the neoplastic luminal epithelial cells and myoepithelial cells in some areas. The neoplastic luminal epithelial cells in 12 malignant tumours reacted strongly for MMP-9. MMP-2 immunolabelling was observed in both benign and malignant tumour tissues, but was stronger in the latter. Zymography and densitometry showed that expression of MMP-9 was higher in the benign mammary tumours than in normal canine mammary tissues, but highest in the malignant mammary tumours. In benign and malignant canine mammary tumours, the zymography and densitometry results for MMP-9 accorded well with the immunohistochemical results obtained with anti-human MMP-9 monoclonal antibody.

Adenocarcinoma↗

PubMed2002

Cytosolic ratio of malate dehyrogenase/lactate dehydrogenase activity in peripheral leukocytes of race horses with training.

The activities of the enzymes involved in the malate-aspartate shuttle and m RNA expression of malate dehydrogenase (MDH), a crucial enzyme for the NADH shuttle that produces ATP in glucose metabolism in the peripheral leukocytes of horses, were measured to investigate the change in metabolic states with training. There were no significant differences in plasma glucose and immunoreactive insulin concentrations between race horses and riding horses, used as a comparable reference. The cytosolic and mitochondrial MDH activities in leukocytes of race horses were significantly higher than those of riding horses. High activities of MDH in leukocytes of race horses were confirmed by RT - PCR analysis on the total RNA extracted from the whole blood. The cytosolic ratio of MDH /lactate dehydrogenase (LDH) activity (M/L ratio) in leukocytes of race horses was significantly higher than in those of riding horses. Increase in the M/L ratio was considered to reflect elevation of energy metabolism in animal tissues. The M/L ratio may be a useful parameter to evaluate the difference in metabolic states between race horses and riding horses.

Animals↗

PubMed2002

Eimeria organisms develop in the epithelial cells of equine small intestine.

Histopathologic and immunohistochemical examinations were performed to determine the origin of host cells parasitized by Eimeria in the small intestines collected from five foals. Eimeria organisms at various stages (mainly microgametes and macrogametes) were frequently found in the cytoplasm of hypertrophied host cells in the lamina propria at the tips of villi of the jejunum and ileum. The cytoplasm of the host cell was immunohistochemically positive for cytokeratin AE1/AE3 and cytokeratin 13 and was negative for vimentin, desmin, alpha-smooth muscle actin, chromogranin A, neuron-specific enolase, and factor VIII. The host cells parasitized by Eimeria species had the immunostaining characteristics of epithelial cells but not of mesenchymal cells, endothelial cells of lacteals or capillaries, smooth muscle cells or neuroendocrine cells. These results suggest that the host cell of Eimeria species is possibly derived from intestinal epithelial cells and then displaced into the lamina propria of the small intestine.

Actins↗

PubMed2001

Theophylline chronotherapy of nocturnal asthma using bathyphase of circadian rhythm in peak expiratory flow rate.

We studied the efficacy of theophylline chronotherapy for nocturnal asthma using the changes of the circadian rhythms in peak expiratory flow rate (PEF). Eight patients with nocturnal asthma were evaluated for the periods with nocturnal symptoms and with an evening dose of theophylline administered daily. Patients recorded their PEF every 4 hours on one of the days (from 7:00 to 23:00 h) in each period. Circadian rhythms in PEF were examined using the single and group-mean cosinor method. Significant circadian rhythms in PEF were observed in the period with nocturnal symptoms. When nocturnal symptoms were present, the bathyphase of PEF was present between midnight and morning. A significant circadian rhythm disappeared or PEF amplitude decreased during theophylline chronotherapy. The circadian rhythm in PEF was altered according to the severity of the asthma. In patients with symptoms present between midnight and early morning, an evening dose of theophylline chronotherapy can be prophylactically used for nocturnal asthma attacks. Consideration of the circadian rhythm and bathyphase of PEF is useful in selecting appropriate chronotherapy for nocturnal asthma.

Adult↗

PubMed2001

Interaction mechanism between indoxyl sulfate, a typical uremic toxin bound to site II, and ligands bound to site I of human serum albumin.

PURPOSE: The study was performed for clarifying the mechanism of interaction between indoxyl sulfate (IS), a typical uremic toxin bound to site II, and site I-ligands when bound to human serum albumin (HSA). The effect of the N to B transition on the interactions was also examined. METHODS: Quantitative investigation of the relations between ligands bound to HSA was performed by equilibrium dialysis, and the binding data were analyzed on the basis of a theoretical model for simultaneous binding of two ligands. RESULTS: The high-affinity binding constants for the site I-ligands warfarin (WF) and dansyl-L-asparagine (DNSA) increased with increasing pH, whereas those for the site II-ligands IS and dansylsarcosine (DNSS) were hardly affected by pH. Mutual displacement experiments showed that even though IS binds to site II it influenced binding of DNSA at the azapropazone binding area in site I. By contrast, it is unlikely that IS affects the WF binding area of site I. Furthermore, pH-profiles showed that the interaction between IS and DNSA was very sensitive to the N to B transition: "competitive-like" strong allosteric regulation was observed for binding of the two ligands to the N conformer (pH 6.5), whereas in the B conformation (pH 8.5) binding of these molecules was nearly "independent". CONCLUSIONS: The present data provide useful information for elucidating a potential mechanism of interaction between drugs and endogenous substances including uremic toxins.

Anticoagulants↗

PubMed2001

Nonlinear behavior of human respiratory movement during different sleep stages.

To investigate the nonlinear properties of respiratory movement during different sleep stages, we applied an algorithm proposed by Grassberger and Procaccia to calculate the correlation dimension in rapid eye movement and non-rapid eye movement sleep. We also tested for nonlinearity in respiratory movement by comparing the correlation dimension for the original data with that for surrogate data. The study population included eight healthy volunteers. We recorded respiratory movement and the sleep electroencephalogram for 8 h. The correlation dimension for respiratory movement was 3.28+/-0.19 (mean +/- SD) during rapid eye movement sleep, 2.31+/-0.21 during light sleep (stage I) and 1.64+/-0.25 during deep slow-wave sleep (stage IV). Thus, the correlation dimension differed significantly by sleep stage (p < 0.001): it was least during stage IV sleep and greatest during REM. The correlation dimension for the original data also differed from that for surrogate data, confirming nonlinearity in original data. The results suggest that the nonlinear dynamics of respiratory movement in sleep changes with sleep stage, presumably due to the information processing by the cerebral cortex. The increased correlation dimension for respiratory movement in REM sleep may be related to increased cortical information processing associated with dreaming.

Adult↗

PubMed2001

Enhanced antigen-specific delayed-type hypersensitivity and immunoglobulin G2b responses after oral administration of viable Lactobacillus casei YIT9029 in Wistar and Brown Norway rats.

In this study, the effects of orally administered viable Lactobacillus casei Shirota strain YIT9029 on the immunity parameters of Wistar and Brown Norway rats were examined. For this purpose, we used the Trichinella spiralis host resistance model. Two weeks before and during T. spiralis infection, rats were fed 10(9) viable L. casei bacteria 5 days per week. The T. spiralis-specific delayed-type hypersensitivity (DTH) response was significantly enhanced in both Wistar and Brown Norway rats given L. casei. In both rat strains fed L. casei, serum T. spiralis-specific immunoglobulin G2b (IgG2b) concentrations were also significantly increased. In the model, no significant effects of L. casei on larval counts or inflammatory reactions in the tongue musculature, body weights, or lymphoid organ weights were observed. Serum specific antibody responses, other than IgG2b, were not changed by feeding of L. casei. In contrast to L. casei, it was shown that orally administered Bifidobacterium breve or Bifidobacterium bifidum had no influence on the measured infection and immunity indices in the rat infection model. Since the rat DTH response is considered to be a manifestation of Th1 cell-mediated immunity and the IgG2b isotype has been associated with Th1 activity, it was concluded that Th1 cells could play an active role in the immunomodulatory effects of orally administered L. casei. Furthermore, our data do not indicate that the effect of oral supplementation with L. casei is dependent on the genetic background of the host.

Actinomycetales Infections↗

PubMed2001

Escherichia coli ribosome-associated protein SRA, whose copy number increases during stationary phase.

Protein D has previously been demonstrated to be associated with Escherichia coli ribosomes by the radical-free and highly reducing method of two-dimensional polyacrylamide gel electrophoresis. In this study, we show that protein D is exclusively present in the 30S ribosomal subunit and that its gene is located at 33.6 min on the E. coli genetic map, between ompC and sfcA. The gene consists of 45 codons, coding for a protein of 5,096 Da. The copy number of protein D per ribosomal particle varied during growth and increased from 0.1 in the exponential phase to 0.4 in the stationary phase. For these reasons, protein D was named SRA (stationary-phase-induced ribosome-associated) protein and its gene was named sra. The amount of SRA protein within the cell was found to be controlled mainly at the transcriptional level: its transcription increased rapidly upon entry into the stationary phase and was partly dependent on an alternative sigma factor (sigma S). In addition, global regulators, such as factor inversion stimulation (FIS), integration host factor (IHF), cyclic AMP, and ppGpp, were found to play a role either directly or indirectly in the transcription of sra in the stationary phase.

Amino Acid Sequence↗

PubMed2001

Validity of NIR spectroscopy for quantitatively measuring muscle oxidative metabolic rate in exercise.

The purpose of this study was to examine the validity of the quantitative measurement of muscle oxidative metabolism in exercise by near-infrared continuous-wave spectroscopy (NIRcws). Twelve male subjects performed two bouts of dynamic handgrip exercise, once for the NIRcws measurement and once for the (31)P-magnetic resonance spectroscopy (MRS) measurement as a standard measure. The resting muscle metabolic rate (RMRmus) was independently measured by (31)P-MRS during 15 min of arterial occlusion at rest. During the first exercise bout, the quantitative value of muscle oxidative metabolic rate at 30 s postexercise was evaluated from the ratio of the rate of oxyhemoglobin/myoglobin decline measured by NIRcws during arterial occlusion 30 s after exercise and the rate at rest. Therefore, the absolute values of muscle oxidative metabolic rate at 30 s after exercise [VO(2NIR(30))] was calculated from this ratio multiplied by RMRmus. During the second exercise bout, creatine phosphate (PCr) resynthesis rate was measured by (31)P-MRS at 30 s postexercise [Q((30))] under the same conditions but without arterial occlusion postexercise. To determine the validity of NIRcws, VO(2NIR(30)) was compared with Q((30)). There was a significant correlation between VO(2NIR(30)), which ranged between 0.018 and 0. 187 mM ATP/s, and Q((30)), which ranged between 0.041 and 0.209 mM ATP/s (r = 0.965, P < 0.001). This result supports the application of NIRcws to quantitatively evaluate muscle oxidative metabolic rate in exercise.

Adenosine Triphosphate↗

PubMed2001

Effect of herb supplement on hepatic enzyme activities in ddY mice.

Plasma glucose and lipid concentrations and hepatic enzyme activities were measured in male ddY mice supplemented with the herb, Echevaria glauca, to examine the effect of herbal treatment. In mice supplemented with the herb, plasma triglyceride (TG) and free fatty acid (FFA) concentrations decreased and hepatic glycolytic enzyme and glutathione peroxidase (GSHpx) activities increased significantly compared with those in the non-treated control mice. These increases in hepatic enzyme activities were not fully dose-dependent, however the higher dose and longer duration with herb supplement induced increases in the enzyme activities. It was found that dietary herb supplement caused an acceleration of hepatic function, judged by increased activities of glycolytic enzyme and GSHpx in ddY mice.

Administration, Oral↗

PubMed2001

Changes in activities of enzymes related to malate-aspartate shuttle in leukocytes from dogs given a herb supplement.

Changes in activities of enzymes related to the malate-aspartate shuttle were measured in leukocytes (WBC) from dogs given food supplemented with 2 mg/kg of herb powder, Echevaria glauca, every day for 4 weeks. There were no significant differences in plasma concentrations of glucose, immunoreactive insulin, free fatty acids and triglyceride between dogs given food with or without the herb supplementation. Activities of malate dehydrogenase (MDH) and aspartate aminotransferase (AST) in the malate-aspartate shuttle increased remarkably in mitochondria of WBC from dogs fed the herb supplementation. It is suggested that Echevaria glauca herb supplementation might activate NADH shuttle systems and mitochondrial energy metabolism in dogs.

Animals↗

PubMed2001

Immunohistochemical detection of apolipoprotein B-100 and immunoglobulins (IgA, IgM, IgG) in the splenic arteries of aging dogs.

Accumulation of lipids and hyalinosis in the splenic arteries of aged dogs are frequently detected by routine histopathologic examinations. The purpose of this study was to pinpoint the localization of canine apolipoprotein B-100 (CApoB-100) and immunoglobulins (IgA, IgM, IgG) in the splenic arteries of aging dogs (n = 80) through the use of immunohistochemical techniques. CApoB-100 deposits were found in the subendothelial space, extracellular matrix, and atheromatous lesions in the tunica media of the arteries in dogs > or = 6 years of age. Foamy cytoplasm of the infiltrated macrophages was also CApoB-100 immunopositive. In dogs > or = 10 years of age, almost all central arteries were CApoB-100 immunopositive. Hyaline deposits within the wall were characterized by immunopositivity against canine IgA, IgM, IgG, and albumin. Lipid accumulation in splenic arteries may be an age-related lesion and a precursor of the atheromatous plaques associated with splenic hemorrhage and infarcts later in life. In addition, deposition of immunoglobulins, probably mediated by immune complexes, may play an important role in the development of canine vascular diseases similar to human disease.

Age Factors↗

PubMed2001

Immunohistochemical evaluation of a malignant phecochromocytoma in a wolfdog.

A malignant pheochromocytoma with multiple metastases was diagnosed in a 7-year-old male wolfdog that resulted from a cross between an eastern timber wolf (Canis lupus lycaon) and an Alaskan malamute. A yellowish white neoplastic mass approximately 10 cm diameter was found in the right adrenal gland. The neoplasm penetrated through the wall of the caudal vena cava. A diagnosis of pheochromocytoma was established by histopathologic and immunohistochemical procedures. Immunohistochemically, the neoplastic cells expressed chromogranin A, substance P, synaptophysin, Leu-7, protein gene product 9.5, methionine-enkephalin, S100 protein, and galanin. Multiple metastatic tumors were found in the kidneys, spleen, lungs, heart, and liver.

Adrenal Gland Neoplasms↗

PubMed2001

[Lung cancer metastasis to the gingiva].

A 70-year-old man was referred to our hospital complaining of left gingival tumors with bleeding, halitosis and impediments to eating and speaking. Tumors were also found in both lungs, the stomach, the intestines and the right adrenal gland. Biopsies of the gingiva and the stomach pointed to undifferentiated carcinoma. Although the patient was treated with carboplatin plus 5-fluorouracil, the gingival tumors did not change in size. Subsequently, the gingival tumors were irradiated with a total dose of 39 Gy, and disappeared completely. The patient died 78 days later of hemorrhage of the digestive tract. Postmortem examination revealed that the primary tumor was in the left lung. Nineteen cases of lung cancer metastatic to the gingiva have been reported. The prognosis in all was very poor, and the QOL was compromised. However, several cases have improved with therapy to the gingiva. We believe that initial therapy should be directed at metastatic gingival tumors of the lung.

Adenocarcinoma↗

PubMed2001

[A case of stage IV advanced lung adenocarcinoma treated effectively using paclitaxel with the fibrosing radiographically on the chest CT].

A 48-year-old man presented with dyspnea. He was diagnosed as having advanced lung adenocarcinoma of stage IV (T4N2M1). After 3 courses of paclitaxel therapy every 3 weeks intravenously, subjective symptoms, arterial blood gas and radiographical findings improved very much. In the process of the tumor reduction, chest CT showed unique radiographical findings of so-called lung fibrosis over the entire lung and reduction of lung volume. An additional 3 courses of weekly paclitaxel therapy have been given on an outpatient basis. After the change of therapy, the reduction in the tumor has continued and the tumor progression is under control without a decline in the patient's QOL from the start of the chemotherapy over 6 months to the present.

Adenocarcinoma↗

PubMed2000

Insertion of bacteriophage phiFSW into the chromosome of Lactobacillus casei strain Shirota (S-1): characterization of the attachment sites and the integrase gene.

The integrase gene (int) on the genome of φFSW, which is a temperate bacteriophage of Lactobacillus casei strain Shirota (formerly denoted as S-1), and the four attachment sites on the genomes of the phage and its host were characterized by sequencing. The φFSW integrase was found to belong to the integrase family of site-specific tyrosine recombinase. The attachment sites shared a 40bp common core within which an integrative site-specific recombination occurs. The common core was flanked on one side by an additional segment of high sequence similarity. An integration plasmid, consisting of int, the phage attachment site (attP), and a selectable marker, inserted stably into the bacterial attachment site (attB) within the common core, as did the complete prophage genome at a frequency of more than 10(3)/microg of plasmid DNA. This plasmid was used as a test system for a preliminary mutational analysis of int and attP. The attB common core was located within and near the end of an open reading frame that appears to encode a homolog to glucose 6-phosphate isomerase, an enzyme of the glycolytic pathway. It is unlikely that the prophage integration inactivates this protein, since a change of only the C-terminal amino acid is predicted because of the sequence similarity between attP and attB.

Amino Acid Sequence↗

PubMed2000

Clinical and in vitro evaluation of membrane humidifier that does not require addition of water.

It is well known that conventional bubbling humidifiers are capable of producing micro-aerosols contaminated with bacteria. We developed a unique humidifier, named a membrane humidifier, that does not require an external water supply. This new system obtains moisture from room air. We investigated the clinical and in vitro evaluation of the membrane humidifier. Ten patients with chronic pulmonary disease participated in the study. We evaluated the partial pressure of oxygen in arterial blood (PaO2) of 10 patients who used the new device. We conducted an in vitro study to determine whether the device could prevent the bacterial contamination of humidified-oxygen. We passed compressed air contaminated with Pseudomonas aeruginosa outside the hollow fibres of the membrane humidifier, and the humidified-oxygen passed inside the hollow fibres was sampled into nutrient broth periodically for 10 days. We also compared the relative humidity of oxygen humidified by a membrane humidifier with that of oxygen humidified by a bubbling humidifier. There was no significant difference between measured PaO2 while breathing oxygen humidified using a membrane humidifier and that while breathing oxygen humidified using a bubbling humidifier. Cultures of the humidified-oxygen passed through the hollow fibres were negative for bacteria. The membrane humidifier could produce good humidification. The new device appeared to prevent bacterial contamination, and may help to reduce the risk of infection in patients at hospital and home.

Aged↗