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Biomedical subjects

F Kondo

Publications and source records attributed to F Kondo.

At least 37 records · Page 2Linked to original sources
PubMed2001

DNA diversity of the wla gene cluster among serotype HS:19 and non-HS:19 Campylobacter jejuni strains.

Campylobacter jejuni infection is an important trigger of Guillain-Barré syndrome (GBS), and serotype HS:19 strains are over-represented among GBS-associated isolates. Structures in C. jejuni lipooligosaccharide (LOS) resemble human gangliosides, suggesting that molecular mimicry could be important in triggering the neural injury. We assessed the genetic diversity among 36 C. jejuni serotype HS:19 and non-HS:19 strains by analysis of PCR-based restriction fragment length polymorphism (RFLP) patterns of 12 LOS biosynthesis-related genes (wla cluster). PCR amplification revealed that the size, order, and direction of each wla gene was identical among all strains tested. However, an additional ORF, located between wlaI and wlaK, was detected in 28 of the 36 isolates examined, and nucleotide sequence analysis revealed that the gene was identical to orfE in C. jejuni strain NCTC 11168. An inverted repeat motif was found downstream of the wlaI stop codon and upstream of the orfE stop codon, an organization allowing pairing of repeated sequences that could lead to deletion of the internal segment. Digestion of the PCR products with restriction endonuclease DdeI or AluI and cluster analysis of RFLP banding patterns showed that all HS:19 strains were closely related and distinct from non-HS:19 strains, consistent with earlier analyses, suggesting that HS:19 strains represent a highly clonal population. RFLP analysis of wla genes also may be useful for epidemiological studies.

Base Sequence↗
PubMed2000

Delayed neuronal death in hippocampal CA1 pyramidal neurons after forebrain ischemia in hyperglycemic gerbils: amelioration by indomethacin.

Hyperglycemia worsens ischemic-induced neuronal damage. Many reports argue the delayed neuronal cell death (DND) after forebrain ischemia in gerbils is due to apoptosis. We examined the effects of hyperglycemia and indomethacin on DND after forebrain ischemia in gerbils. Complete occlusion of both common carotid arteries was performed for 3.5 min followed by declamping and reperfusion. Blood glucose levels were maintained at 25-30 mmol/1 for 24 h after reperfusion in the hyperglycemic groups. We examined morphological changes consistent with DND using Nissel-stained sections and DNA fragmentation using TUNEL staining, at 12, 24, 36, 48, 60, 72, 84, 96, 108, 120 h, and 7 days after reperfusion. DND was noted 96-120 h after ischemia in normoglycemic group. Hyperglycemia enhanced the development of DND at an earlier stage (48-84 h after ischemia). TUNEL positive neurons were detected 72-108 h after reperfusion in normoglycemic group, but very few TUNEL positive neurons were detected in hyperglycemic group at 36-48 h. Indomethacin reduced the number of TUNEL-positive cells in normoglycemia and completely inhibited the appearance of TUNEL-positive cells under hyperglycemia. The number of viable neurons at 7 days after ischemia was markedly higher in indomethacin-treated groups than vehicle-treated group. Our results indicate that hyperglycemia worsens DND after forebrain ischemia in gerbils but such process is not associated with DNA fragmentation. Our results also showed that indomethacin provides a neuroprotective effect in normo- and hyperglycemic conditions.

Animals↗
PubMed2000

First report on the distribution of orally administered microcystin-LR in mouse tissue using an immunostaining method.

The purpose of this study was to investigate the distribution of microcystin-LR (MCLR) orally administered to mice using an immunostaining method. MCLR was orally dosed at 500 microg/kg to aged Balb/C and ICR mice and their lethality was 23.9%. The former was more sensitive to MCLR than the latter, suggesting that oral toxicity by MCLR is related to the animal strains tested, although the pathological and immunostaining changes were essentially the same in both strains. According to this method the distribution of MCLR and related compounds were indicated as the red staining. Particularly, livers of dead aged mice were intensively stained. The main route of absorption was considered to be the small intestine because the villi contained a large amount of MCLR in both surface epithelial cells and lamina propria, resulting in erosion. The absorbed MCLR was contained in blood plasma and moved to the liver, lung, and heart, and finally to capillaries of the whole body. Excretion of MCLR was shown in the mucous from goblet cells in both the small intestine and large intestine.

Animals↗
PubMed2000

Immunoaffinity purification method for detection and quantification of microcystins in lake water.

We have developed a new clean-up method, which consisted of solid-phase extraction on a Sep-Pak PS-2 (styrene-divinylbenzene copolymer) or Excelpak SPE-GLF (polymethacrylate) cartridge instead of conventional ODS silica gel and silica gel together with following immunoaffinity purification using anti-microcystin-LR monoclonal antibodies. This newly developed method was demonstrated to eliminate co-existing substances and to concentrate microcystins in the lake water. The recoveries from lake water (1 liter) spiked with 100 ng each of microcystins-RR, -YR and -LR were 85.5, 89.2 and 92.2%, respectively, with coefficients of variation of 3.3-7.6%. Only 3 h were required to complete the total procedures starting from the microcystin extraction, the immunoaffinity purification, and the quantification using HPLC. The detection limits for all of the 3 microcystins in lake water were 0.005 microg/l. Applicability of this method has been demonstrated by measuring the concentrations of microcystins in water samples collected from lakes where water blooms occurred, which turned out to be 0.012-0.177 microg/l of total microcystins.

Antibodies, Monoclonal↗
PubMed2000

Relationship between copper, zinc and metallothionein in hepatocellular carcinoma and its surrounding liver parenchyma.

BACKGROUND/AIM: Accumulation of copper (Cu) in hepatocellular carcinoma (HCC), especially in small tumors, is greater than that in the surrounding liver parenchyma. Metallothionein (MT) is considered to be present as Cu-MT, Zn,Cu-MT or Zn-MT. The aim of this study was to determine the presence and localization of Cu-MT and Zn-MT in HCC and surrounding liver parenchyma. METHODS: In 16 HCC patients, surgically resected specimens including HCC and surrounding liver parenchyma were evaluated. RESULTS: The level of Cu present in small HCC (<4 cm in diameter) was significantly greater than that in the surrounding liver parenchyma (p<0.05). However, the level of Cu in large HCC (>4 cm in diameter) was similar to that in the surrounding liver parenchyma. Analysis by Sephadex G-75 gel filtration revealed that the peak fraction due to Cu was identical to that due to MT in 14 (87.5%) of 16 HCC, the peak fraction due to Cu and Zn was identical to that due to MT in 2 (12.5%) HCC, and the peak fraction due to Zn was identical to that of MT in none of 16 HCC. CONCLUSIONS: Accumulation of Cu in small HCC, in which Cu was present as Cu-MT or Zn, Cu-MT, was greater than that in the surrounding liver parenchyma. Cu accumulation and the presence of MT in the liver may be related to carcinogenesis of HCC, because of the similarity of these findings in the experimental data of Long-Evans rats with a cinnamon-like coat color who develop HCC spontaneously.

Adult↗
PubMed2000

Isolation of Campylobacter species from zoo animals and polymerase chain reaction-based random amplified polymorphism DNA analysis.

A total of 104 fecal specimens from 30 mammals, 12 birds, and 3 reptiles at the Phoenix Zoological Gardens, Miyazaki City, Japan, were examined for the presence of Campylobacter species. All the animals examined were healthy with no fecal abnormality. Twenty-three (22.1%) thermophilic campylobacters, (9 C. jejuni, 11 C. hyointestinalis, 2 C. coli, and 1 C. lari), were isolated from 11 animals (7 mammals and 4 birds). C. jejuni and C. hyointestinalis were the predominant species isolated from these zoo animals and C. hyointestinalis was isolated frequently from simians. As selective media influence the numbers and species of campylobacters isolated, the agar medium was not supplemented with cephalothin. Campylobacters were isolated most frequently when a combination of enrichment culture and selective agar plating was performed at 42 degrees C. For the epidemiological study, a polymerase chain reaction (PCR)-based randomly amplified polymorphic DNA (RAPD) method was used as a tool to detect the heterogeneity of amplified DNAs of Campylobacter spp. isolated from zoo animals. The two arbitrary primers used in this study enabled even closely related strains of the same Campylobacter spp. to be differentiated. RAPD analysis revealed considerable diversity among the strains, suggesting that the transmission of Campylobacter spp. among animals in a defined area occurred through different mechanisms. Examination of the genotypic diversity among the multiple clones from the same host also revealed differences between clones. These results demonstrate that campylobacter populations in zoo animals are highly divergent.

Animals↗
PubMed2000

Protective effect of oren-gedoku-to against induction of neuronal death by transient cerebral ischemia in the C57BL/6 mouse.

We examined the neuroprotective effects of oren-gedoku-to (TJ15), a herbal medicine, after transient forebrain ischemia. Transient forebrain ischemia was induced by occlusion of both common carotid arteries for 15 min in C57BL/6 mice treated with TJ15. In the control ischemic group without TJ15 treatment, histologic examination of brain tissue collected seven days after reperfusion showed death of pyramidal cells in CA2-3 area of the hippocampus, unilaterally or bilaterally. In mice treated with oral TJ15 (845 mg/kg/day) for five weeks, the frequency of ischemic neuronal death was significantly lower. Immunohistochemistry for Cu/Zn-superoxide dismutase (Cu/Zn-SOD) showed strongly reactive astrocytes in the hippocampus of ischemic mice treated with TJ15. Damage to nerve cells by free radicals plays an important role in the induction of neuronal death by ischemia-reperfusion injury. Our results suggest that TJ15 protects against ischemic neuronal death by increasing the expression of Cu/Zn-SOD and suggest that oren-gedoku-to reduces the exposure of hippocampal neurons to oxidative stress.

Animals↗
PubMed2000

Accumulation of copper in the liver and hepatic injury in chronic hepatitis C.

BACKGROUND AND AIMS: Relationships between chronic liver disease and trace metals have not been clearly understood. To examine connections between severity of hepatic fibrosis in chronic hepatitis C and copper, iron and zinc we measured the contents of these metals in liver tissue and serum in the patients. METHODS: Forty-one patients (26-62 years), 13 with fibrosis representing grade F1, 16 with F2, seven with F3, and five with F4, entered this study. Metals were quantified in needle liver-biopsy specimens by particle-induced X-ray emission. In serum, metals were measured by flameless atomic absorption spectrometry. RESULTS: Hepatic copper content increased with progression of hepatic fibrosis (P < 0.05). The copper content correlated positively with bilirubin (r = 0.466, P = 0.0023), and with type IV collagen (r = 0.402, P = 0.0086) and correlated negatively with albumin (r = -0.404, P = 0.080). However, hepatic iron and zinc contents did not show a significant differences between grades of fibrosis. CONCLUSIONS: Copper accumulation in fibrotic livers caused by chronic hepatitis C may contribute to hepatic injury. The real mechanism is not known at present, but excess copper may damage the liver by oxidative stress.

Adult↗
PubMed2000

Effect of bicozamycin on the eradication of Shiga toxin-producing Escherichia coli in calves.

Fifty-nine calves, aged 11 days to 9 months, from three farms breeding Japanese Black beef cattle in Miyazaki Prefecture, Japan, were examined for the presence of Shiga toxin-producing Escherichia coli (STEC). A high prevalence of STEC was detected among calves, with 45 (76.3%) animals carrying STEC including different serogroups (O26, O74, O111, O114, O119, O127, O153, O157, and ONT) and toxin types. The number of STEC in the feces was estimated by a combined method involving enumeration of colony-forming units by a plate-most-probable-number (plate-MPN) technique and polymerase chain reaction for the detection of Shiga toxin genes. Fecal shedding ranged from 10(1) to 10(10) MPN/g feces. To evaluate the safety and efficacy of bicozamycin (BCM: previously named as bicyclomycin) in eradicating STEC, 30 calves carrying STEC with or without diarrhea were examined. Fifteen calves were treated orally with BCM (10 mg/kg/day) once daily for 5 days, and the other 15 were untreated. Twenty-four hours after the last dose, fecal specimens were collected from both groups to compare the number of coliforms and STEC with those before treatment. BCM-treated animals had a significantly lower number of coliforms and STEC compared to the untreated calves. The STEC eradication rate was 86.6% (13/15) in the BCM-treated group, compared to 0% (0/15) in the control group. The corresponding cure rates for diarrhea were 87.5 (7/8) and 0% (0/3), respectively. No adverse reactions were observed in the calves during treatment. It is concluded that BCM is an effective agent for the eradication of STEC in calves with or without diarrhea.

Animals↗
PubMed2000

[Total analysis system for tumor promoter microcystins produced by cyanobacteria].

Microcystins, produced by freshwater cyanobacteria, are cyclic peptide hepatotoxins and tumor promoters. An outbreak of human poisoning attributed to microcystins has been reported in Caruaru, Brazil in 1996, where exposure through renal dialysis led to the death of 50 patients. Although such severe acute effects on human health seem to be rare, microcystins poses problems to human health which could result from low-level, chronic exposure to microcystins in drinking water. It is therefore important to monitor the levels of microcystins in water reservoirs where cyanobacterial blooms occur. We have developed a total analysis system for microcystins using GC-MS and LC-MS. This comprises initial screening of samples to check for the presence of microcystins by detecting 2-methyl-3-methoxy-4-phenylbutyric acid as an ozonolysis product using thermospray interface LC-MS and electron ionization/GC-MS. If a sample is positive in a screening test, it will be necessary to follow through with identification and quantification. Frit-FAB interface LC-MS allowed the rapid identification of microcystins in cyanobacteria and lake water, and also enabled us to identify microcystins and their metabolites formed in vivo in mouse liver. Finally, Frit-FAB/LC-MS using selected ion monitoring could be used for quantitative analysis of microcystins in lake water in the low nanogram range. The total analysis system proposed in the present study should be applicable to studies of the metabolism of microcystins, of their detoxification, and those of the mechanism(s) of the accumulation in the food chain.

Animals↗
PubMed2000

Detection, quantitation, and identification of residual aminopenicillins by high-performance liquid chromatography after fluorescamine derivation.

A high-performance liquid chromatographic (HPLC) method with fluorescence detection after precolumn fluorescamine derivation was developed to detect residues of two aminopenicillins, amoxicillin (AMPC) and ampicillin (ABPC), in bovine serum. Proteins in serum samples spiked with each of these penicillins were precipitated with sodium tungstate and sulfuric acid, centrifuged, and removed by passage through a C18 solid-phase extraction cartridge. After precolumn treatment of the extraction products of AMPC and ABPC with fluorescamine solution, HPLC analysis with fluorescence spectrophotometric detection at an excitation wavelength of 390 nm and an emission wavelength of 485 nm was performed to identify these products. Two mobile phases were used for residual analysis by the isocratic HPLC system. An ODP column (polyvinyl alcohol bonded with an octadecyl functional group) that can be used with strongly alkaline mobile phases (pH 2.0 to 13) was selected, and the column temperature was set at 40 degrees C. A mobile phase comprising 100-mM K2HPO4 solution and acetonitrile (72:28, vol/vol), which yielded AMPC and ABPC retention times of 4.1 and 7.9 min, respectively, was suitable for detection of residual ABPC but not for residual AMPC because interference was caused by peaks of other extracted substances. When a mobile phase comprising a different ratio of 100-mM K2HPO4 solution and acetonitrile (78:22, vol/vol) was used, the retention times of AMPC and ABPC were 7.3 and 26.3 min, respectively, and both penicillins could be analyzed using this system. The calculated standard curves of the reaction products with both mobile phases were linear, and the correlation coefficients were greater than 0.999. The lower limit of detection was 10 ng/ml for both penicillins. Analysis of extracts from bovine serum spiked with AMPC and ABPC at a concentration of 1 microg/ml yielded recovery rates of 102.2 +/- 5.5% and 79.0 +/- 5.2%, respectively. This detection method may be useful for routine laboratory testing of AMPC and ABPC.

Amoxicillin↗
PubMed2000

[A randomized long-term comparative study of clinical efficacy of alpha 1-blocker with or without antiandrogen therapy for benign prostatic hyperplasia: focusing on improvement of I-PSS].

This study was conducted to examine the efficacy of administration of tamsulosin hydrochloride alone or in combination with chlormadinone acetate (CMA) against lower urinary tract symptoms for a period of 52 weeks in 33 patients with benign prostatic hyperplasia. The patients were randomly allocated into a group administered tamsulosin alone and a group administered tamsulosin in combination with CMA. Based on the assessment of the total I-PSS (International Prostate Symptom Score), significant symptomatic improvement was noted 4 weeks after the commencement of drug administration in the tamsulosin + CMA group, whereas no significant improvement was observed in the tamsulosin group. Both irritative and obstructive bladder symptoms improved significantly at any time of assessment after 4 weeks of drug administration in the tamsulosin + CMA group; however, significant improvement was noted only at week 16 and week 52 for irritative symptoms and at week 16 for obstructive symptoms in the tamsulosin group. In particular, obstructive symptoms showed significant improvement at week 4 in the tamsulosin + CMA group, as compared with that in the tamsulosin group. The average value of peak urinary flow rate was significantly increased in the tamsulosin + CMA group (10.4 ml/s to 15.6 ml/s) as compared with that in the tamsulosin group (8.5 ml/s to 10.5 ml/s). These findings indicate that combined administration of tamsulosin and CMA resulted in early improvement of lower urinary tract symptoms in these patients. Long-term combined administration of tamsulosin and CMA thus appears to be a promising treatment strategy for the improvement of obstructive symptoms and peak urinary flow rate, particularly, 16 weeks onward after administration in patients with benign prostatic hyperplasia.

Adrenergic alpha-Antagonists↗
PubMed1999

Early detection of radiation-induced liver injury in rat by superparamagnetic iron oxide-enhanced MR imaging.

The detectability of early liver injury induced by irradiation was studied using magnetic resonance (MR) imaging enhanced with superparamagnetic iron oxide (SPIO), a tissue-specific contrast agent against the reticuloendothelial system (RES). In rat, 3 days after focal irradiation (0-10 Gy), MR imaging was performed and specimens were obtained to observe the phagocytic function of RES. The irradiated portion of the liver was visualized with a clear demarcation from the nonirradiated part by SPIO-enhanced MR images as a decrease in negative enhancement reflecting the function of RES (P < 0.05), whereas this was impossible with nonenhanced MR images. Significant regression was observed as a dose-related change of the signal intensity in the irradiated portion on SPIO-enhanced MR images (R = 0.867, P < 0.0001). SPIO-enhanced MR imaging was reliable for detecting the range and extent of liver injury a few days after low-dose irradiation, and it may be a useful procedure for verifying the target area in clinical cases of radiation therapy.

Animals↗
PubMed1999

Early treatment with cyclosporin A ameliorates the reduction of muscarinic acetylcholine receptors in gerbil hippocampus after transient forebrain ischemia.

Recent evidence has suggested that cyclosporin A (CsA), an immunosuppressive agent, has neuroprotective properties. However, its mechanisms associated with this activity remain unclear. We have previously shown that post-ischemic administration of CsA daily for 14 days prevented the decrease of muscarinic acetylcholine receptor binding in the hippocampus in the gerbil model of 5-min transient forebrain ischemia. In the present study, CsA (5 mg/kg, subcutaneously) was administered to each animal just after, 2 and 6 h after ischemia so as not to exert its immunosuppressive effect. Initial CsA treatment significantly restored the declined muscarinic acetylcholine receptor binding of the hippocampus 14 days after ischemia similar to the previous report. However, CsA did not alter reactive changes of astrocytes and microglia in the CA1 area of the hippocampus, which had been suppressed by daily administration. These results indicate that CsA could positively modulate the hippocampal acetylcholine neurotransmission system broken down through the ischemia-induced pyramidal cell death and its action mechanism may have no relation to the immunosuppressive properties.

Animals↗
PubMed1999

Stool smears for diagnosis of intestinal acute graft-versus-host disease.

A patient with severe diarrhea was successfully diagnosed as having acute intestinal GVHD on stool smear through detection of detached intestinal epithelial cells with apoptosis. Since a stool smear can be easily obtained non-invasively, it is a possible tool for the diagnosis of acute intestinal GVHD.

Acute Disease↗