Search PubMed⌕ Search

Biomedical subjects

S Kubo

Publications and source records attributed to S Kubo.

At least 181 records · Page 10Linked to original sources
PubMed1997

In vivo correction with recombinant adenovirus of 4-hydroxyphenylpyruvic acid dioxygenase deficiencies in strain III mice.

Tyrosinemia type 3, caused by a genetic deficiency of 4-hydroxyphenylpyruvic acid dioxygenase (HPD) in tyrosine catabolism, is characterized by convulsion, ataxia, and mental retardation. The III mouse is a model of tyrosinemia type 3. HPD activity and protein are defective in the liver and its blood tyrosine levels are elevated, the range being between 1,100 and 1,656 microM. We constructed a recombinant adenoviral vector bearing the human HPD cDNA (AdexCAGhHPD), which is expressed under the control of a potent CAG promoter. III mice were injected with 1.0 x 10(8) to 1.0 x 10(9) pfu of AdexCAGhHPD through the tail vein. When 3.0 x 10(8) - 1.0 x 10(9) pfu were injected, blood tyrosine levels decreased within 3 hr, reached a normal range (under 300 microM), and remained at a low level for 2-6 weeks. Hepatic HPD activities also increased as early as 3 hr after the injection of 5.0 x 10(8) pfu, reached the levels comparable to the control mice in 3-7 days, and then decreased, and correlated well to blood tyrosine. Hepatic HPD expression was confirmed by Northern blot and immunoblot analyses. Histology revealed no difference (gross or microscopic) between the liver injected with AdexCAGhHPD and the control. No significant changes in blood tyrosine levels were noted after the second injection of 5.0 x 10(8) pfu of AdexCAGhHPD. Thus, the intravenous administration of the adenoviral vector bearing a foreign gene seems suitable for transient, early gene transfer into the liver.

4-Hydroxyphenylpyruvate Dioxygenase↗
PubMed1997

Chemiluminescence response of whole blood in patients undergoing urological operations.

Polymorphonuclear leukocytes (PMNs) are one of the most important components of the defence mechanisms against bacterial infection. The functions of PMNs are believed to be impaired in patients during the perioperative period. Bactericidal function of PMNs was investigated together with the luminol-dependent chemiluminescence (CL) reaction of whole blood in 23 patients, 12 undergoing open surgery and 11 undergoing endoscopic surgery. Blood samples were collected one day before surgery (day -1) and 2 hours (day 0), 24 hours (day 1) and 7 days (day 7) after surgery. Counts of whole white blood cells (WBCs), PMNs and lymphocytes were not different between the two surgery groups. CL responses in the open surgery group were increased on days 0, 1 and 7. In the endoscopic surgery group, CL response was increased on day 1, but not on day 0 or day 7. These results suggest that the PMN function during the perioperative period was not impaired, but increased just after surgery, mainly due to an increasing number of WBC caused by the surgical intervention.

Adult↗
PubMed1997

High malignancy of hepatocellular carcinoma in alcoholic patients with hepatitis C virus.

BACKGROUND: We investigated the relationships between alcohol consumption, the degree of malignancy evaluated histologically, and tumor-free survival rates. METHODS: In 80 male patients with the hepatitis C virus and small hepatocellular carcinomas (diameter of main tumor, 3.0 cm or less), 38 patients had drunk 86 gm or more of ethanol per day for at least 10 years until the detection of hepatocellular carcinoma (group 1), whereas the remaining 42 patients were nondrinkers or occasional drinkers (group 2). RESULTS: Differences in the results of liver function tests between the groups were not statistically significant. The operative methods used in the groups were comparable. The proportion of well-differentiated hepatocellular carcinoma was lower in group 1 than in group 2 (p < 0.0001). The prevalences of extracapsular invasion, portal tumor thrombi, and intrahepatic metastasis were higher in group 1 than in group 2 (p = 0.0085, p = 0.0319, and p = 0.0428, respectively). The tumor-free survival rate after operation was lower in group 1 than in group 2(p = 0.041 by the log-rank test; p = 0.032 by the generalized Wilcoxon test). CONCLUSIONS: These findings indicate that in group 1, even though tumors were small, the carcinomas were advanced and the outcomes after surgery were poor, suggesting that alcohol affects the grade of malignancy of this disease.

Aged↗
PubMed1997

Poor association of GBV-C viremia with hepatocellular carcinoma.

BACKGROUND/AIMS: The role of the hepatitis GB virus C in chronic liver disease is unclear. The clinical findings, results of laboratory tests, pathological findings, and outcome after liver resection for hepatocellular carcinoma in patients infected or not infected with GB virus C were compared. METHODS: Serum samples from 213 patients were tested for hepatitis B virus, hepatitis C virus, and GB virus C. Of the 213 patients, 159 had hepatitis C viral RNA or antibodies (group 1), seven had both hepatitis C viral RNA or antibodies and hepatitis B surface antigen (group 2), 25 had hepatitis B surface antigen (group 3), and 22 did not have hepatitis C viral RNA, hepatitis C antibodies, or hepatitis B surface antigen (group 4). RESULTS: GB virus C RNA was detected in 12 of the 213 patients. Of the 12 patients, 11 were in group 1 and one was in group 4. There were no patients with hepatocellular carcinoma associated with GB virus C RNA alone. In groups 1 and 4, there were no differences in clinical findings, results of laboratory tests, pathological findings, or outcome after surgery in patients with and without GB virus C RNA. CONCLUSIONS: These results indicate a poor association of GB virus C viremia with hepatocellular carcinoma. We did not find clinically significant interaction between hepatitis C virus and GB virus C.

Adult↗
PubMed1997

CD4 regulates the efficiency of an endogenous superantigen-induced clonal deletion of TCRV beta 11+ cells in the periphery.

Peripheral T-cell antigen receptor V beta (TCRV beta) repertoire is influenced by clonal deletion both in the thymus and periphery. Developing thymocytes expressing certain TCRV beta are deleted by endogenous superantigens presented on major histocompatibility complex (MHC) molecules in the thymus. Likewise, mature T cells bearing particular TCRV beta chains can be clonally deleted by superantigens in the periphery. The efficiency with which T cells expressing particular V beta subunits are deleted differs depending upon which coreceptor is expressed. Indeed, while deletion of V beta 11+ splenic T cells in CBA/J (Mls-1, a I-E, + MTV 9+) mice is quite efficient for CD4+ spleen T cells, it is much less efficient for CD8+ splenic T cells. If the difference in the efficiency of deletion is due solely to the coreceptor expressed, then a transgene encoding CD4 should increase the efficiency with which CD8+ cells are deleted. To address this question, we have produced CD4 transgenic (TG) mice that express physiologic levels of CD4 on all thymocytes and peripheral CD8 T cells. CD4 molecules expressed on CD8+ splenic T cells were associated with P56lck tyrosine kinase, and were functional as evidenced by their ability to facilitate class II alloreactivity. Furthermore, we found that ectopic expression of TG CD4 molecules on CD8+ cells was able to affect the efficiency of deletion in response to superantigen stimulation. In particular, deletion of TCRV beta 11+ T cells was much less efficient for CD8+ than for CD4+ T-cell subpopulations in (CBA/J x B6) F1 mice. However, expression of the CD4 transgene on CD8+ splenic T cells from these mice increased the efficiency of deletion in the CD8+ V beta 11 T cells. Interestingly, this effect was not observed in a mature CD8+ thymocyte subpopulation. The results in this report demonstrate that CD4 molecules are involved in peripheral deletion of TCRV beta 11+ T cells in (CBA/J x B6) F1 mice, and that the TCRV beta repertoire can be altered by ectopic expression of CD4 on all T-lineage cells.

Animals↗
PubMed1997

Determination of 8-hydroxy-deoxyguanosine formation in rat organs: assessment of paraquat-evoked oxidative DNA damage.

Paraquat has previously been shown to cause the oxidative damage to DNA in variety of cells and tissues. However, although paraquat-evoked strand breaks has been extensively studied to assess the DNA damage, the effect of paraquat on base modifications, another marker for the oxidative damage, has not yet been investigated. To further characterize paraquat-evoked DNA damage, the effect of paraquat on 8-hydroxy-deoxyguanosine (8-OH-dG) formation in various rat organs was examined. Paraquat markedly increased 8-OH-dG contents in various organs, particularly in brain, lung and heart, and this increase reached the maximum levels at 5 days after the drug administration. In contrast, the formation of 8-hydroxy-guanosine (8-OH-G), a marker for the oxidative damage to RNA, was not significantly affected by paraquat. These results indicate that paraquat causes base modifications as well as strand breaks as a consequence of the oxidative damage to DNA.

8-Hydroxy-2'-Deoxyguanosine↗
PubMed1997

Isolated adrenocorticotropic hormone deficiency: an autopsy case of adrenal crisis. A case report.

We present a case of fatal adrenal crisis due to isolated adrenocorticotropic hormone (ACTH) deficiency. Autopsy revealed each adrenal gland weighed 0.9 g and the adrenal cortexes were very thin and atrophic. Additionally, cortisol could not be observed in the adrenal cortex by immunohistochemical staining. Furthermore, urine cortisol and 17-OHCS concentration had decreased to a very low level, 20 mg/L and 0.8 mg/L respectively. The anterior pituitary gland was atrophic, and showed fibrosis and lymphocytosis was suspected. Immunohistochemically growth hormone (GH)-stained pituitary gland cells were observed, but there were no cells stained with anti-ACTH antibody. From the history and pathological findings, no other deficiencies of pituitary hormones were evident. Therefore, isolated ACTH deficiency was suspected. Furthermore, as the thyroid gland showed lymphocytic thyroiditis, is was considered that isolated ACTH deficiency was associated with an autoimmune cause. Generally, as patients of chronic adrenocortical insufficiency are exposed to stress and, therefore, have an increased requirement for glucocorticoids, the blood pressure falls, leading to hypovolemic shock called " an adrenal crisis." Without treatment, patients die in crisis within several hours. In our case, the deceased had drunk alcohol without sleep for 2 days. We believe that the stress of drinking and sleeplessness induced adrenal crisis and caused his death.

Acute Disease↗
PubMed1997

Renal scarring by mannose-sensitive adhesin of Escherichia coli type 1 pili.

Most Escherichia coli isolates from patients with pyelonephritis possess both pap (mannose-resistant) pili and type 1 (mannose-sensitive) pili. In the experimental pyelonephritis model of rats, the mannose-sensitive-piliated strain caused severe renal scarring, whereas the mannose-resistant or nonpiliated strain did not. Type 1 pili consist of several subunits; one major subunit and other minor subunits. One of the minor subunits, adhesin, is responsible for mannose-sensitive adhesion to eukaryotic cells. The role of adhesin was examined in scar formation after infection with a newly constructed adhesin-deficient mutant which has pilus structure but cannot agglutinate guinea pig erythrocytes. A mutant plasmid, pYMZ84, containing a deletion in the adhesin gene of type 1 pili, failed to agglutinate guinea pig erythrocytes even though the bacteria expressed pili morphologically indistinguishable from those produced by plasmid pSH2, carrying the intact genes for the type 1 pili. E. coli harboring pYMZ84 caused negligible or minimal renal scarring, whereas E. coli harboring pSH2 caused severe renal scarring in rats. These data suggest that the mannose-sensitive adhesin of type 1 pili stimulates renal scarring.

Adhesins, Escherichia coli↗
PubMed1997

Assessment of beta 2- and beta 3-adrenoceptors in rat white adipose tissues by radioligand binding assay.

We investigated the characteristics of beta-adrenoceptors (beta-ARs) in rat white adipose tissues (WAT) with a radioligand receptor binding assay using (-)-[3H]-CGP12177. Scatchard analysis revealed that there are high- and low-affinity sites for (-)-[3H]-CGP12177 in WAT. The (-)-[3H]-CGP12177 bound to a high-affinity site was displaced by 1 microM propranolol. The rank of pKi values of catecholamines for the site was isoproterenol > epinephrine > norepinephrine. By contrast, BRL37344A, BRL35135A and SR59230A, beta 3-selective agonists had high affinity for the low-affinity site of (-)-[3H]-CGP12177, whereas (-)-[3H]-CGP12177 bound to a low-affinity site was completely displaced by 100 microM bupranolol but not 1 microM propranolol. The pKi values of the catecholamines (isoproterenol, norepinephrine, epinephrine) for this site were very low. In addition, the correlation between the pKi values of various beta-agonists for the low-affinity site of rat WAT and those obtained from rat cloned beta 3-ARs was significant, but those of human cloned beta 3-ARs were not. Consequently, the results suggested that the high- and low-affinity sites were beta 2-ARs and beta 3-ARs in rat WAT, respectively.

Adipose Tissue↗
PubMed1997

Most probable numbers of enterotoxigenic Clostridium perfringens in intestinal contents of domestic livestock detected by nested PCR.

The incidence and numbers of enterotoxigenic Clostridium perfringens in the intestinal contents of cattle, swine and broiler chickens were determined and compared with those of total (enterotoxigenic and nonenterotoxigenic) C. perfringens. The method used for the enumeration of enterotoxigenic C. perfringens consisted of a combination of the most probable number (MPN) method and a nested polymerase chain reaction after enrichment culture of the sample. Enterotoxigenic C. perfringens was found in 26% (4.0 x 10-4.3 x 10(2) MPN/100 g), 22% (4.0 x 10-2.3 x 10(3) MPN/100 g) and 40% (4.0 x 10-2.4 x 10(4) MPN/100 g) of intestinal contents of 50 head each of cattle, swine and broiler chickens, respectively. Whereas, total C. perfringens was found in 76% (9.0 x 10-7.5 x 10(6) MPN/100 g), 44% (7.0 x 10-4.3 x 10(6) MPN/100 g) and 80% (4.3 x 10(2)-9.3 x 10(7) MPN/100 g) of intestinal contents of 50 head each of cattle, swine and broiler chickens, respectively, by the conventional MPN method. In all cases, enterotoxigenic cells were not dominant in the population of C. perfringens: a small number of enterotoxigenic cells of C. perfringens co-existed with a large number of nonenterotoxigenic cells in the same sample. The ratios of enterotoxigenic C. perfringens cells to total C. perfringens cells were 1/10-1/10(5).

Animals↗
PubMed1997

Most probable number method combined with nested polymerase chain reaction for detection and enumeration of enterotoxigenic Clostridium perfringens in intestinal contents of cattle, pig and chicken.

The most probable number (MPN) method combined with a nested polymerase chain reaction (nested PCR) for the detection and enumeration of enterotoxigenic Clostridium perfringens in the intestinal contents of cattle, pig and chicken was examined. Ten-fold serial dilutions of samples were added to three tubes of enrichment medium, which were incubated at 37 degrees C for 20-24 hr, and the C. perfringens enterotoxin gene was detected by nested PCR from the enrichment culture without isolating the organism. The results obtained by this method with artificially contaminated intestinal contents were significantly correlated with those obtained by a plate count method. When the method was applied to the detection and enumeration of indigenous enterotoxigenic C. perfringens, the organism was found in two, two and three samples of 10 intestinal contents of cattle, pig and chicken, respectively. Most of the positive samples contained fewer than 10 MPN/g of enterotoxigenic C. perfringens, except one sample of chicken, which contained 1.5 x 10(2) MPN/g. The MPN method combined with nested PCR is easy to perform and may be a useful tool for the detection and enumeration of enterotoxigenic C. perfringens in intestinal contents.

Animals↗
PubMed1997

Magnetic resonance cholangiography in hepatolithiasis.

OBJECTIVES: Our objective was to examine the usefulness of magnetic resonance cholangiography in hepatolithiasis. METHODS: Ten patients with hepatolithiasis were studied by ultrasonography, computed tomography, direct cholangiography, and magnetic resonance cholangiography to detect stones and to determine the morphological features of the bile ducts. In nine patients who underwent surgery, dilation and stenosis of the bile ducts were confirmed by intraoperative cholangioscopy, pathology, or both. RESULTS: Stones were demonstrated in seven patients by ultrasonography, in eight by computed tomography, in seven by direct cholangiography, and in all by magnetic resonance cholangiography. The locations of stones were identified in four patients by ultrasonography, in seven by computed tomography, in six by direct cholangiography, and in nine by magnetic resonance cholangiography. Among nine patients with dilation of the bile ducts, the dilation was shown by ultrasonography in seven, by computed tomography in eight, by direct cholangiography in six, and by magnetic resonance cholangiography in eight. Among seven patients with stenosis of the bile ducts, this stenosis was shown by direct cholangiography in four and by magnetic resonance cholangiography in six. Ultrasonography and computed tomography did not show the stenosis. Sensitivity for detection of biliary stenosis was significantly higher in magnetic resonance cholangiography. CONCLUSIONS: This study shows that magnetic resonance cholangiography not only detects stones, but can also delineate detailed information on the bile ducts, which is useful in the planning of treatment for hepatolithiasis.

Adult↗
PubMed1997

Concentrations of bile and serum endotoxin and serum cytokines after biliary drainage for acute cholangitis.

Endotoxin contributes to cholangitis. We measured concentrations of bile and serum endotoxin and serum cytokines after biliary drainage for obstructive jaundice with or without acute cholangitis. Patients who underwent percutaneous transhepatic cholangiodrainage (PTCD) in 1995 were classified as having acute cholangitis (group A; n = 11), having a history of acute cholangitis (group B; n = 5), or not having a history of acute cholangitis (group C; n = 13). Bile endotoxin was positive (above the cut-off value) in all patients in groups A and B, and in five patients in group C. The mean concentration of bile endotoxin was significantly higher in groups A and B than in group C. After PTCD, the bile endotoxin level decreased more slowly in group A than in the other groups. Before PTCD, the mean serum levels of IL-1 receptor antagonist (IL-1ra), IL-6, and IL-8 were higher in group A than the other groups. The serum levels of IL-1ra and IL-6 before PTCD were significantly higher when the acute cholangitis was more severe. The mean serum levels of cytokines increased just after PTCD and then decreased. In group A, the serum level of IL-6 at 5 h after PTCD was significantly correlated to the endotoxin level in bile at this time. Increases in cytokines may participate in the pathophysiological changes of acute cholangitis. Biliary drainage for acute cholangitis causes improvement by decreasing the bile endotoxin level addition to decreasing bile-duct pressure, thereby preventing excess production of inflammatory cytokines.

Acute Disease↗
PubMed1997

[Emery-Dreifuss muscular dystrophy].

Emery-Dreifuss muscular dystrophy (EDMD) is an inherited muscular disorder characterized by the triad of progressive weakness in humero-peroneal muscles, early onset contractures and cardiomyopathy with conduction block that shows a high risk of sudden death. In 1994, the gene responsible for X-linked EDMD has been identified to Xq28 (designated as STA), that encodes a serine-rich protein of 254 amino acids, named emerin. In 1996, we discovered a nuclear membrane localization of emerin in the normal skeletal, cardiac and smooth muscles, but not in the tissues from patients with X-linked EDMD who had a nonsense mutation in the gene. In conclusion, molecular and genetic analyses of emerin are essential for accurate diagnosis of patients with EDMD.

Cardiomyopathies↗
PubMed1997

[The drug sensitivity of enterohemorragic Escherichia coli and antibiotics treatment for hemorrhagic enterocolitis--from an outbreak of enterocolitis in Sakai city].

In July, 1996, a massive outbreak of hemorrhagic enterocolitis involving more than 5,000 people was caused by enterohemorragic Escherichia coli (EHEC) O157:H7 occurred mainly among elementary school children of Sakai City, Japan. The antibacterial activities in vitro against EHEC from stool specimens were determined. Norfloxacin showed the highest antibacterial activity, and fosfomycin, kanamycin, ampicillin, cefaclor were considered as effective drugs. But doxycycline showed lower antibacterial activities compared to other examined drugs, and it appears necessary to take antibiotic resistance of Escherichia coli into consideration when a treatment regimen is determined. As a result of the oral administration of fosfomycin to 95 patients of hemorrhagic enterocolitis and carrier, no patients developed complications with hemolytic uremic syndrome (HUS). However, a study of 17 patients with HUS demonstrated the fact that most of them were subjected to intravenous administration of fosfomycin. It may be needed to consider oral administration route of effective antibiotics in the treatment of enterocolitis in order to maintain high concentrations of a drug in the intestine.

Administration, Oral↗
PubMed1996

Oxidative folding of omega-conotoxin MVIIC: effects of temperature and salt.

Oxidative folding of omega-conotoxin MVIIC, a highly basic 26-amino acid peptide with three disulfide bonds, predominantly gave two products with mismatched disulfide bonds in 0.1M NH4OAc buffer (pH 7.7) at 21 degrees C both in the presence and absence of redox reagents such as reduced and oxidized glutathione. A low reaction temperature (5 degrees C) and a high salt concentration in buffer such as 2M (NH4)2SO4 were necessary to obtain the correctly folded biologically active product. The folding reaction was found to proceed via a two-stage pathway of (I) the formation and (II) the rearrangement of the mismatched disulfide bonds. Both the reaction temperature and the salt strongly affected the equilibrium between mismatched and correctly formed disulfide bonds in the second stage. Such an effect of salts on the rearrangement reaction could be explained by anion binding at a low concentration and the salting out effect at a high concentration by analyzing the rank order of their effectiveness. The anion-binding effect was also confirmed by examining the folding of the tetra-acetylated peptide at the Lys side chains. CD study suggested that the yield of the biologically active product was correlated with its conformational change as functions of temperature and salt concentration.

Acetates↗
PubMed1996

Analysis of 69 patients with amebic liver abscess.

All 69 patients with amebic liver abscess that we treated in 1981-1992 were studied retrospectively. Men predominated by a 10:1 ratio. Of our 227 patients with amebiasis, some 30% yearly had liver involvement. The incidence peaked in 1988, decreasing later but increasing again in 1992. Most patients were 30-50 years old, the overall mean age being 45 years (range, 22-79), and decreasing with time. Patients with the related factors of travel abroad, positive results of a test for Treponema pallidum hemagglutination, and homosexuality have increased in number in recent years. Fever, abdominal pain, and hepatomegaly were the most frequent findings, and 39 patients had neither bloody stools nor diarrhea. Only 8 patients had had amebiasis previously. A solitary abscess in the right lobe of the liver was found in 40 patients. Entamoeba histolytica was found in the stool of 31 patients and in the pus of 39 patients. Sixty-one patients had positive results for an amebic serological test(s). The abscesses ruptured into the peritoneal cavity in 4 patients. All patients received metronidazole. Percutaneous or surgical drainage (or both) was done in 62 patients. The outcome was good, with 1 exception, and only 2 patients had recurrences.

Adult↗