Biomedical subjects

Y Maede

Publications and source records attributed to Y Maede.

At least 37 records · Page 2Linked to original sources

PubMed1999

Possible causes of diabetes mellitus in cattle infected with bovine viral diarrhoea virus.

In cattle, we encountered insulin-dependent diabetes mellitus (IDDM) associated with bovine viral diarrhoea virus (BVDV) infection. To estimate the correlation between IDDM and BVDV infection, the distribution of BVDV in the pancreas and islet-cell antibody (ICA) were investigated. The distribution of BVDV in the pancreas was examined by in situ hybridization using two oligonucleotide probes that recognized the gp25- and p14-coding regions of the BVDV gene. ICA was examined by indirect fluorescence antibody assay using the sera from affected cattle and pancreata from normal cattle. In the pancreata of all BVDV-infected cattle, including IDDM-complicated cattle, oligonucleotide probe hybridized portions were recognized. In short, BVDV genes were detected not only in IDDM-complicated cattle but also in uncomplicated cattle. Moreover, there was no hybridized portion in the islet cells. In BVDV-infected and IDDM-complicated cattle, ICA was frequently detected. On the other hand, ICA was not detected in BVDV-infected and IDDM uncomplicated cattle. These results suggest that IDDM associated with BVDV infection is not a direct effect of BVDV on islet cells. Therefore, as BVDV did not induce IDDM in any cases, it appears that BVDV does not induce IDDM directly, but rather may be an autoimmune disease induced by autoantibodies against islet cells.

Animals↗

PubMed1999

Thymidine phosphorylase expression in progression of cervical cancer: correlation with microvessel count, proliferating cell nuclear antigen, and apoptosis.

AIMS: To determine how epithelial and stromal thymidine phosphorylase expression affects angiogenesis, rapid tumour growth, and decreased apoptotic activity in cervical cancer at varying stages of progression. METHODS: Epithelial and stromal thymidine phosphorylase expression, the microvessel count (reflected by factor VIII related antigen), and proliferating cell nuclear antigen (PCNA) were assessed immunohistochemically in 25 specimens of normal cervical epithelium, 35 of carcinoma in situ (CIS), 34 of microinvasive carcinoma, and 34 of invasive cervical squamous cell carcinoma. Apoptosis was evaluated by the terminal deoxynucleotidyl transferase mediated dUTP-biotin nick end labelling (TUNEL) method. The relation of epithelial and stromal thymidine phosphorylase expression to microvessel count, PCNA index, and apoptotic index was examined. RESULTS: Epithelial and stromal thymidine phosphorylase expression progressively increased along a continuum from normal epithelium to invasive squamous cell carcinoma. Epithelial and stromal thymidine phosphorylase expression showed a significant positive correlation with microvessel counts. Within each histological stage, CIS cases with high stromal thymidine phosphorylase expression, invasive squamous cell carcinoma cases with high epithelial thymidine phosphorylase expression, and microinvasive carcinoma cases with high thymidine phosphorylase expression in both epithelium and stroma had a significantly higher microvessel count. High epithelial thymidine phosphorylase expression was associated with a significantly higher PCNA index in CIS and microinvasive carcinoma, but not in invasive squamous cell carcinoma. No significant correlation was seen between apoptotic index and either epithelial or stromal thymidine phosphorylase expression or microvessel count. CONCLUSIONS: Epithelial and stromal thymidine phosphorylase expression may combine to promote angiogenesis during progression of cervical cancer, and epithelial thymidine phosphorylase expression may stimulate tumour cell proliferation in the early stages.

Apoptosis↗

PubMed1999

Relation between erythrocyte reduced glutathione and glutamate concentrations in Korean Jindo dogs with erythrocytes possessing hereditary high activity of Na-K-ATPase and a high concentration of potassium.

The concentrations of sodium, potassium, reduced glutathione (GSH) and free amino acids and Na-K-ATPase activity in erythrocytes were examined in 35 purebred Jindo dogs in Korea. The incidence of Jindo dogs with a high potassium concentration and high activity of Na-K-ATPase in erythrocytes (HK phenotype) was 25.7%. The erythrocyte GSH concentration in HK Jindo dogs varied widely, from 2.45 to 12.38 mmol/l of RBCs, and was positively correlated with the erythrocyte glutamate concentration. These results indicate that HK Jindo dogs have normal to very high levels of erythrocyte GSH, which might result from the varying quantity of Na-dependent glutamate influx in the erythrocytes.

Animals↗

PubMed1999

Rumen ciliate protozoal fauna of native sheep, friesian cattle and dromedary camel in Libya.

Rumen ciliate species and composition were surveyed on the native sheep, Friesian-cattle and dromedary (one-humped) camels kept in Libya. As a result of survey, 5 genera including 14 species with 5 formae in native sheep, 9 genera including 27 species with 6 formae in Friesian-cattle and 6 genera including 13 species and 7 formae in dromedary camels were identified. All of the ciliate species and their percentage composition detected from the Libyan sheep and cattle in this examination were similar to those found from corresponding animals in the other countries. Libyan camels lacked some peculiar ciliate species found from camels in the other countries, but had many cosmopolitan species common with those in the domestic ruminants, suggesting that ciliate faunae of camel are easily affected by the other domestic ruminants kept together. The ciliate density was estimated as 105/ml in every host species.

Animals↗

PubMed1999

Rumen bacteria are involved in the onset of onion-induced hemolytic anemia in sheep.

The mechanism of onion-induced hemolytic anemia in ruminants was investigated. The ether-extract obtained from the mixture of rumen fluid and onion juice incubated at 38.5 degrees C for 9 hr induced oxidative damage in sheep erythrocytes in vitro, indicating the production of certain oxidants in the mixture. The increase of the oxidative effect in the mixture was inhibited completely by the removal of rumen microorganisms and partly by treatment with antibiotics and by oxygen gas. The sheep fed onions (50 g/kg body weight/day) for 15 days developed more severe Heinz body hemolytic anemia than did the sheep fed the equivalent amount of onions with 5 g/day ampicillin sodium salt. The results indicated that certain rumen bacteria appear to be involved in the onset of onion-induced hemolytic anemia in sheep.

Anemia, Hemolytic↗

PubMed1999

Prognosis of patients with stage IIIb-IVa squamous cell carcinoma of the cervix following intra-arterial neoadjuvant chemotherapy.

Our purpose was to determine the long-term prognosis in patients with stage IIIb-IVa squamous cell carcinoma of the cervix who were treated with intra-arterial neoadjuvant chemotherapy (NAC), and to analyze factors related to prognostic value. We assessed the disease-free survival of 21 patients with FIGO stage IIIb-IVa squamous cell carcinoma of the cervix treated with intra-arterial NAC (cisplatin 70 mg/m2 and peplomycin sulfate 30 mg/m2) followed by irradiation therapy. Before chemotherapy, five factors (age, clinical stage, histologic type, parametrial involvement and serum level of SCC) were evaluated for their correlation with disease-free survival. The absolute 5-year disease-free survival rate for the entire group was 52%, with a median follow-up time in disease-free survivors of 87 months. Among the prognostic factors, age was the only one to be significantly correlated with disease-free survival; older (> 60 years) patients showed a significantly better disease-free survival rate than did younger (< 60 years) patients (p < 0.05, log-rank test). The absolute 5-year disease-free survival rate was 69% for older patients and 25% for younger patients. Univariate Cox's proportional hazard model also demonstrated that age was a significant prognostic factor as a continuous variable (p < 0.01). Intra-arterial NAC thus appeared to be effective in treating older patients with stage IIIb-IVa squamous cell carcinoma of the cervix.

Adult↗

PubMed1999

Co-expression of vascular endothelial growth factor and thymidine phosphorylase in endometrial cancer.

OBJECTIVE: To examine expression of vascular endothelial growth factor (VEGF) and thymidine phosphorylase (TP) together with microvessel count in endometrial cancer, and to investigate the relationship with clinicopathological and biological factors. METHODS: VEGF expression, TP expression, the microvessel count (factor VIII-related antigen positive cells), bcl-2 expression, proliferating cell nuclear antigen (PCNA) index, and p53 expression were determined in 50 resected endometrial cancer specimens, using immunohistochemistry. The relationship between VEGF and TP expression and correlation between expression and microvessel count were also given attention. These 3 factors were analyzed with regard to clinicopathological factors, bcl-2 expression, PCNA index, and p53 expression. RESULTS: Staining status of VEGF and TP was identical in 37 (74%) of 50 tumors, the correlation being statistically significant (p < 0.01). Combined analysis of VEGF and TP status showed that tumors which were VEGF-positive and/or TP-positive had a significantly higher microvessel count than did tumors which were both VEGF-negative and TP-negative (p < 0.001 and p < 0.05, respectively). TP expression correlated with bcl-2 expression, and VEGF expression inversely correlated with the PCNA index. Although clinical stage (p < 0.01), PCNA index (p < 0.01), and p53 expression (p < 0.01) significantly correlated with disease-free survival, neither VEGF/TP expression nor microvessel count contributed to prognostic estimates. CONCLUSIONS: VEGF and TP may cooperatively promote angiogenesis in endometrial cancer, but these expressions may have limited additional prognostic value.

Adult↗

PubMed1998

Induction of onion-induced haemolytic anaemia in dogs with sodium n-propylthiosulphate.

The haemolytic effect of sodium n-propylthiosulphate, which had been isolated from boiled onions, was studied to determine whether it could be one of the agents responsible for induced haemolytic anaemia in dogs. The oral administration of 500 mumol/kg bodyweight of the compound to dogs resulted in a haemolytic anaemia associated with an increase of Heinz body formation in erythrocytes, which was more severe in dogs with the hereditary condition which results in erythrocytes with high concentrations of reduced glutathione and potassium than in normal dogs. In the affected dogs there was a 10-fold increase in the concentration of oxidised glutathione in their erythrocytes 12 hours after the administration of the compound, whereas in normal dogs there was almost no change.

Anemia, Hemolytic↗

PubMed1997

Distribution of bovine immunodeficiency virus in the organs of experimentally infected cows.

The distribution of bovine immunodeficiency virus (BIV) in the organs of experimentally infected cows was investigated by use of nested polymerase chain reaction (PCR). Two cows (Nos. 1 and 2) experimentally infected with BIV were alive without any clinical symptoms of BIV infection for 28 months. Viral and proviral genomes of BIV were continuously detected from peripheral blood leukocytes in those cows by nested PCR. Proviral genomes of BIV were also detected in liver, lung, and spleen cells in the two cows, and in the brain in cow No. 1. Viral genomes were detected in liver, lung and spleen cells in cow No. 1, and detected only in spleen cells in cow No. 2. These results suggest that BIV tended to be persistent in some organs, especially in the spleen.

Animals↗

PubMed1996

Defective anion transport and marked spherocytosis with membrane instability caused by hereditary total deficiency of red cell band 3 in cattle due to a nonsense mutation.

We studied bovine subjects that exhibited a moderate uncompensated anemia with hereditary spherocytosis inherited in an autosomal incompletely dominant mode and retarded growth. Based on the results of SDS-PAGE, immunoblotting, and electron microscopic analysis by the freeze fracture method, we show here that the proband red cells lacked the band 3 protein completely. Sequence analysis of the proband band 3 cDNA and genomic DNA showed a C --> T substitution resulting in a nonsense mutation (CGA --> TGA; Arg --> Stop) at the position corresponding to codon 646 in human red cell band 3 cDNA. The proband red cells were deficient in spectrin, ankyrin, actin, and protein 4.2, resulting in a distorted and disrupted membrane skeletal network with decreased density. Therefore, the proband red cell membranes were extremely unstable and showed the loss of surface area in several distinct ways such as invagination, vesiculation, and extrusion of microvesicles, leading to the formation of spherocytes. Total deficiency of band 3 also resulted in defective Cl-/HCO3- exchange, causing mild acidosis with decreases in the HCO3- concentration and total CO2 in the proband blood. Our results demonstrate that band 3 indeed contributes to red cell membrane stability, CO2 transport, and acid-base homeostasis, but is not always essential to the survival of this mammal.

Animals↗

PubMed1996

Oxidative damage and enhanced erythrophagocytosis in canine erythrocytes infected with Babesia gibsoni.

Oxidative damage to canine erythrocytes infected with Babesia gibsoni was investigated. B. gibsoni was cultured together with erythrocytes from normal dogs. When parasitemia reached a peak level, concentrations of both methemoglobin (metHb) and malondialdehyde (MDA), an end product of lipid peroxidation, in erythrocytes were significantly higher than at cultivation Day 0. In addition, B. gibsoni-infected dogs with high parasitemia showed significant increases of both metHb and MDA concentration in erythrocytes compared to those in uninfected dogs. Furthermore, erythrocytes from parasitized culture were more susceptible to phagocytosis by bone marrow macrophages from normal dogs than erythrocytes from the control culture. In addition, macrophages ingested not only parasitized erythrocytes but also non-parasitized cells. These results suggested that oxidative damage to erythrocytes was induced by the multiplications of B. gibsoni, and that non-parasitized erythrocytes were also exposed erythrocytes oxidative stress during the infection by B. gibsoni.

Animals↗

PubMed1996

Hemoglobin types, erythrocyte membrane skeleton and plasma iron concentration in calves with poikilocytosis.

The pathogenesis of poikilocytosis in calves was investigated. Nine calves 1 to 2 months old exhibiting poikilocytosis (poikilocytic calves), were examined. The proportion of poikilocytes in their blood was more than 70% in two calves (severely poikilocytic), while it averaged 30% in the remaining seven calves (moderately poikilocytic). All of the polikilocytic calves exhibited mild anemia. The concentration of plasma iron in 8 of them was 20-30% of that in normal calves, but it increased as the calves aged. The polikilocyte count in moderately poikilocytic calves decreased in proportion to the increase of the plasma iron concentration, though a high poikilocyte count was observed in a severely poikilocytic calf even after the plasma iron concentration reached the normal level. Column chromatography of a hemoglobin preparation from all the calves examined revealed 5 distinct peaks. Three peaks were embryonic, fetal and adult hemoglobins, respectively. The other peaks were tentatively designated Hb-2 and Hb-3, respectively. The amount of Hb-2 in the two severely poikilocytic calves was about three times that in the other calves including those moderately poikilocytic, and it decreased as the calves aged. The decrease of Hb-2 in one severely poikilocytic calf was related to a reduction of the proportion of poikilocytes in its peripheral blood. There was no significant difference in age-dependent changes of hemoglobin types between moderately poikilocytic calves and normal calves. Furthermore, SDS-PAGE analysis of red cell membrane revealed that protein 4.2 consisted of two polypeptides in the two severely poikilocytic, and three moderately poikilocytic calves, while it consisted of a single polypeptide in the remaining calves examined. These results indicated that the abnormalities of hemoglobin composition and protein 4.2 in the erythrocyte membrane observed in the severely poikilocytic calves might be responsible for the morphological changes in the erythrocytes, whereas iron deficiency was thought to be the predominant cause of poikilocytosis in the moderately poikilocytic calves.

Anemia↗

PubMed1996

Comparative study of rumen ciliates in buffalo, cattle and sheep in Egypt.

Rumen ciliates species and composition of the sheep, Friesian-cattle and water buffaloes in Egypt were surveyed. As a result, 7 genera with 18 species and 6 formae in sheep, 10 genera with 28 species and 11 formae in cattle and 12 genera with 29 species and 7 formae in water buffaloes were detected. Twenty-two species were common in both cattle and buffaloes, while 12 species in sheep were common with the other ruminants. Entodinium spp., such as E. simplex, E. nanellum and E. exigum, appeared most frequently in every host. In general, Egyptian domestic ruminants had the rumen ciliate composition similar to that of domestic ruminants in temperate zone, though the water buffaloes had several tropical species such as Entodinium longinucleatum forma spinonucleatum. The ciliate density was estimated as 10(5)/ml in every host species.

Animals↗

PubMed1996

Ciliate protozoa in the forestomach of the dromedary camel, (Camelus dromedarius), in Egypt, with description of a new species.

The composition of ciliates obtained from the forestomachs of eleven dromedary (one-humped) camels in Egypt was examined. As a result, eight genera containing 24 species with 11 forms were identified. Of them, one species was concluded to be new, then described as Dasytricha kabanii n. sp. This new species was clearly distinguished from D. ruminantium, the other species of the genus, by its lack of somatic cilia on the posterior one-fifth of the body surface. Entodinium nanellum and Epidinium ecaudatum f. caudatum were found in all camels examined. Although the percentage composition of respective species varied with the individual camel, the rate of Entodinium spp. was high in general. Total ciliate density in forestomach fluid was 1.9 x 10(5)/ml on average. Ciliate composition in Egyptian camels was similar to that in Bactrian camels, Camelus bactrianus, in China reported previously. However, more Entodinium species were detected from Egyptian camels than from Bactrian camels.

Animals↗

PubMed1996

Hemolytic anemia in wild seaducks caused by marine oil pollution.

Clinico-pathological examinations were conducted on wild white-winged scoters (Melanitta fusca) contaminated with fuel oil (Bunker C oil) from a capsized cargo ship in February 1993 in Japan. The erythrocyte count, hemoglobin concentration and hematocrit value in the oiled seaducks all were decreased and numerous immature erythrocytes were observed in blood smears. In addition, hemosiderosis was observed in the liver, kidney, and lung of some birds. We propose that the sea-ducks suffered from hemolytic anemia induced by ingestion of oil, which occurs when the birds preen their oiled plumage.

Alanine Transaminase↗

PubMed1994

Characterization of Na(+)-dependent L-glutamate transport in canine erythrocytes.

Characteristics of the high-affinity Na(+)-dependent L-glutamate transport system in canine erythrocytes were studied by using intact cells and resealed ghosts. The L-glutamate transport showed a precise dependence on extracellular Na+ and intracellular K+. Kinetical analysis revealed that two Na+ ions and one K+ ion were involved in each L-glutamate transport cycle. The L-glutamate transport was inhibited most potently by threo-3-hydroxyaspartate and L-cysteinesulfinate (at 25 microM, 83% and 79% inhibition, respectively) and weakly by dihydrokainate and DL-alpha-aminoadipate (at 25 microM, 21% and 17% inhibition, respectively). From these stoichiometrical and pharmacological properties we concluded that the L-glutamate transport system in canine erythrocytes is a product of the L-glutamate transporter gene family and resembles a neuronal transporter rather than a glial one. L-Glutamate uptake was increased by internal, but not external, HCO3- when the internal and external anions of the erythrocytes were replaced by several other anions. Moreover, this enhancement was blocked by inhibition of carbonic anhydrase, which indicated that L-glutamate transport was at least partly dependent on HCO3- generated inside the cells. These observations indicate that anion countertransport is coupled to the high-affinity Na(+)- and K(+)-dependent L-glutamate transport in canine erythrocytes.

Animals↗

PubMed1994

Mechanism of hemolysis of canine erythrocytes induced by L-sorbose.

The cause of species difference in the susceptibility of erythrocytes to L-sorbose, and the difference in the hemolytic effect of sorbose on high potassium-containing (HK) and low potassium-containing (LK) canine erythrocytes were examined. L-Sorbose was phosphorylated in canine erythrocytes, but not in human erythrocytes. Furthermore, sorbose-1-phosphate, a metabolite of L-sorbose, strongly inhibited the hexokinase of LK canine erythrocytes, but not that of HK canine erythrocytes. These results strongly indicated that inhibition of hexokinase by sorbose-1-phosphate in LK erythrocytes induced severe glycolytic limitation in these cells, resulting in hemolysis, and that HK erythrocytes are resistant to sorbose-induced hemolysis because these cells have a high hexokinase activity.

Animals↗

PubMed1993

Direct evidence for preferential multiplication of Babesia gibsoni in young erythrocytes.

To clarify the effect of the age of host erythrocytes on the multiplication of Babesia parasites, B. gibsoni was cultured together with reticulocytes, immature erythrocytes, or mature erythrocytes from dogs. Parasitemia reached peak levels (34.1% +/- 15.8%) at cultivation day 8 in immature-erythrocyte culture, whereas the highest parasitemia attained in mature-cell culture was only 3.6% +/- 2.2% at day 5. These results clearly demonstrate that B. gibsoni parasites preferentially invade and multiply in young erythrocytes rather than in mature cells.

Animals↗