Biomedical subjects

K Uchida

Publications and source records attributed to K Uchida.

At least 415 records · Page 23Linked to original sources

PubMed1998

Genomic organization of Drosophila poly(ADP-ribose) polymerase and distribution of its mRNA during development.

Poly(ADP-ribosyl)ation of proteins catalyzed by poly(ADP-ribose) polymerase (PARP; EC 2.4.2.30) modulates several biological activities. However, little is known about the role of PARP in developmental process. Here we report the organization of the Drosophila PARP gene and the expression patterns during Drosophila development. The Drosophila PARP gene was a single copy gene mapped at 81F and composed of six exons. Organization of exons corresponds to the functional domains of PARP. The DNA-binding domain was encoded by exons 1, 2, 3, and 4. The auto-modification domain was encoded by exon 5, and the catalytic domain was in exon 6. The promoter region of the PARP gene contained putative TATA box and CCAAT box unlike human PARP. Expression of the PARP gene was at high levels in embryos at 0-6 h after egg laying and gradually decreased until 8 h. PARP mRNA increased again at 8-12 h and was observed in pupae and adult flies but not in larvae. In situ mRNA hybridization of embryos revealed large amount of PARP mRNA observed homogeneously except the pole cells at the early stage of embryos, possibly due to presence of the maternal mRNA for PARP, and decreased gradually until the stage 12 in which stage PARP mRNA localized in anal plates. At late stage of embryogenesis PARP mRNA was localized in cells along the central nervous system.

Amino Acid Sequence↗

PubMed1998

Protein-bound acrolein: potential markers for oxidative stress.

Acrolein (CH2==CH---CHO) is known as a ubiquitous pollutant in the environment. Here we show that this notorious aldehyde is not just a pollutant, but also a lipid peroxidation product that could be ubiquitously generated in biological systems. Upon incubation with BSA, acrolein was rapidly incorporated into the protein and generated the protein-linked carbonyl derivative, a putative marker of oxidatively modified proteins under oxidative stress. To verify the presence of protein-bound acrolein in vivo, the mAb (mAb5F6) against the acrolein-modified keyhole limpet hemocyanin was raised. It was found that the acrolein-lysine adduct, Nepsilon-(3-formyl-3, 4-dehydropiperidino)lysine, constitutes an epitope of the antibody. Immunohistochemical analysis of atherosclerotic lesions from a human aorta demonstrated that antigenic materials recognized by mAb5F6 indeed constituted the lesions, in which intense positivity was associated primarily with macrophage-derived foam cells and the thickening neointima of arterial walls. The observations that (i) oxidative modification of low-density lipoprotein with Cu2+ generated the acrolein-low-density lipoprotein adducts and (ii) the iron-catalyzed oxidation of arachidonate in the presence of protein resulted in the formation of antigenic materials suggested that polyunsaturated fatty acids are sources of acrolein that cause the production of protein-bound acrolein. These data suggest that the protein-bound acrolein represents potential markers of oxidative stress and long-term damage to protein in aging, atherosclerosis, and diabetes.

Acrolein↗

PubMed1998

Histochemical detection of 4-hydroxynonenal protein in Alzheimer amyloid.

The presence of lipid peroxidation product in amyloid deposits from seven patients with Alzheimer disease and nine with non-Alzheimer disease was examined immunohistochemically by means of an affinity purified anti-HNE antibody to hydroxynonenal (HNE), a marker of lipid peroxidation. A positive reaction was found in amyloid deposits in all the specimens examined: most of the perivascular areas (89%) where amyloid deposition was confirmed by Congo red staining, showed immunoreactivity with the antibody in the specimens of Alzheimer disease. Twenty-one percent of senile plaques which were also stained by Congo red staining reacted with this antibody. Several perivascular cells were also stained by anti-HNE antibody. In other neurons both in Alzheimer and non-Alzheimer disease patients, only a few percent reacted with this antibody and no statistical difference was observed between them. These results verify that lipid peroxidation via free radical injury occurs in amyloid deposits in Alzheimer amyloid. Since HNE has been identified as a cytotoxic metabolite of free radical injury, amyloid deposits in the tissue may exhibit a toxic effect during the generation process of HNE.

Aged↗

PubMed1998

Nipradilol inhibits DNA synthesis by regulating nitric oxide synthesis in cultured rat mesangial cells.

To elucidate whether nipradilol modulates mesangial cell function, we assessed the effects of nipradilol on DNA synthesis in the presence and absence of N-nitro-L-arginine methyl ester (L-NAME) in cultured rat mesangial cells stimulated with 1% fetal bovine serum. Nipradilol inhibited [3H]thymidine incorporation into mesangial cells in a dose- and time-dependent manner. In addition, the anti-mitogenic effect of 100 microM nipradilol was significantly inhibited in the presence of 10 microM L-NAME. Moreover, nipradilol increased intracellular cyclic guanosine monophosphate (cGMP). These results suggest that nipradilol exerts its efficacy in the treatment of several types of glomerulonephritis with mesangial cell proliferation by increasing in intracellular cGMP.

Adrenergic beta-Antagonists↗

PubMed1998

Molecular cloning of human TAK1 and its mutational analysis in human lung cancer.

In previous reports, we described that DPC4/Smad4 and Smad2 are mutated in a fraction of human lung cancers and suggested possible roles of the downstream mediators of transforming growth factor-beta (TGF-beta)-elicited signals in the pathogenesis of this most common cancer. In the present study, we investigated whether another downstream mediator, human TGF-beta-activated kinase 1 (hTAK1), also is altered in lung cancer. For this purpose, the hTAK1 gene was cloned with the aid of an expression sequence tag database search and cDNA library screening, and hTAK1 was found to be expressed ubiquitously in 2 distinct isoforms regulated in a tissue-specific manner in fetal and adult normal tissues. Interestingly, hTAK1 was assigned to the chromosome region 6q14-21, which is deleted frequently in various human malignancies, including lung cancer. Despite our extensive search for alterations in 39 lung cancer specimens as well as in 16 lung cancer cell lines, somatic mutations of hTAK1 were not identified, indicating that hTAK1 itself is not a frequent target for genetic alterations in lung cancer.

Amino Acid Sequence↗

PubMed1998

Inhibition of human T-cell leukemia virus type 1 replication by antisense env oligodeoxynucleotide.

Human T-cell leukemia virus type 1 (HTLV-1) infection is associated with adult T-cell leukemia and HTLV-associated myelopathy/tropical spastic paraparesis. Inhibition of HTLV-1 transmission is important to prevent the above HTLV-1-associated diseases. We used the antisense oligodeoxynucleotides (oligos) complementary to the first splice junction, rex responsive site, gag, env, tax, rex, and p21 and evaluated the effects on the syncytium formation between HTLV-1 producing human T-cell line, C9/PL cells, and HTLV-1-uninfected human glioma cell line, U251-MG cells. The syncytium formation was significantly inhibited the virion production assayed by antisense oligos to env, tax, gag, p21, and rex, with antisense oligo to env being the most inhibitory. Antisense oligos to env and tax also inhibited reverse transcriptase activity. Antisense oligo to env may have a potential as a preventive measure of HTLV-1 replication and transmission in vivo.

Base Sequence↗

PubMed1998

Effect of erythrocytapheresis on arterial oxygen saturation and hemoglobin oxygen affinity in patients with sickle cell disease.

An important purpose of blood transfusion in patients with sickle cell disease is to improve arterial oxygen saturation (SaO2) and thereby reduce red cell sickling. To investigate the degree of improvement in SaO2 by blood transfusion, we determined the hemoglobin oxygen affinity, transcutaneous oxygen saturation (Tc-SO2), and pulse rate before and after automated partial exchange transfusion (erythrocytapheresis). In 13 patients with sickle cell disease who underwent 24 erythrocytapheresis procedures, the mean oxygen tension at half saturation (P50) was significantly reduced from 30.4 +/- 2.2 to 26.0 +/- 1.6 mm Hg (P< 0.01) immediately after exchange transfusion. Mean Tc-SO2 values increased from 96.2 +/- 2.8 to 98.5 +/- 2.1% (P< 0.01). Approximately 50% of the increase in Tc-SO2 after erythrocytapheresis could be explained by the increase in hemoglobin oxygen affinity. An increase in arterial oxygen pressure (PaO2) following erythrocytapheresis, suggested by the calculated PaO2 in this study, may explain some of the increase in Tc-SO2. We conclude that improvement in Tc-SO2 in patients with sickle cell disease resulted from changes in hemoglobin oxygen affinity as well as blood oxygen pressure following erythrocytapheresis.

2,3-Diphosphoglycerate↗

PubMed1998

Fibrosis accelerates the development of enzyme-altered lesions in the rat liver.

Injection of pig serum into rats twice a week for 8 weeks induced stellate cell activation resulting in liver fibrosis without parenchymal cell injury. Administration of a choline deficient L-amino acid defined (CDAA) diet for 6 weeks with or without pig serum pretreatment led to the development of preneoplastic lesions that were positive for the placental form of glutathione S-transferase (GSTP). Pig serum pretreatment induced more activated stellate cells in the livers of rats subsequently fed a CDAA diet for 6 weeks compared with rats fed the CDAA diet alone. Activated stellate cells were detected as smooth muscle actin (SMA)-positive cells and by the expression of SMA messenger RNA. These cells caused severe fibrosis as assessed by the hepatic hydroxyproline content. Pre-existing fibrosis induced by the activation of stellate cells with pig serum pretreatment increased hepatic malondialdehyde (MDA) level in parallel with GSTP-positive lesions. These results indicate that pre-existing fibrosis with the activated stellate cells accelerates the development of preneoplastic lesions in a CDAA diet model.

Actins↗

PubMed1998

Localization of cortisol receptor in branchial chloride cells in chum salmon fry.

To clarify the involvement of cortisol in functional differentiation of branchial chloride cells, cellular gene expression and localization of cortisol receptor were examined in chum salmon (Oncorhynchus keta) fry in freshwater (FW) and those adapted to seawater (SW) by in situ hybridization and immunocytochemical staining. Sodium-potassium adenosinetriphosphatase (Na+,K(+)-ATPase) activity in the whole gill homogenate was significantly higher in SW fish than in FW fish. There were no significant differences in plasma cortisol levels nor in the expression of cortisol receptor mRNA, examined by Northern blot analysis, between SW and FW fish. The receptor gene expression, examined by in situ hybridization with biotin-labeled synthetic oligonucleotide probe, and specific immunostaining with anticortisol receptor serum were found in two types of chloride cells distributed in the gill filaments and lamellae, which were also labeled with anti-Na+,K(+)-ATPase serum, indicating that cortisol may be one of the important factors regulating chloride cell functions. Gene expression of cortisol receptor in filament chloride cells, which were highly activated in SW-adapted fry, was significantly greater in the fry adapted to SW than in FW-adapted fry, reflecting their specific role in salt secretion in SW. Cortisol receptors were also present in undifferentiated cells in the interlamellar regions adjacent to the central venous sinus, also suggesting the involvement of cortisol in the functional differentiation of chloride cells.

Animals↗

PubMed1998

Clinical evaluation of irreversible data compression for computed radiography of the hand.

We evaluated the clinical utility of high data compression for computed radiography (CR) of the hand. Paired original and compressed CR images were obtained using an FCR 9000 system in 35 patients with various abnormalities of the hand. For the paired original and compressed images, we compared the depiction of the bone cortex, bone trabeculae, soft-tissue, and the margin of the abnormalities. The overall impressions for detectability of the abnormalities and for diagnostic capability were also evaluated. Poorer image quality of the compressed images was noted for most of the structures, but there was no significant difference between the original and compressed images as for the overall impressions for detectability of the abnormalities or for diagnostic capability. We conclude that a high data compression may be clinically acceptable with caution in radiography of the hand.

Female↗

PubMed1998

Clinical evaluation of irreversible data compression for computed radiography of the chest.

Efficient data compression is essential for practical daily operation of computed radiography (CR) systems. In this study the clinical applicability of type III irreversible high data compression using an FCR 9501 chest unit (Fuji Photo Film, Tokyo, Japan) was evaluated. Sixty-eight normal and 93 various abnormal cases, with an additional 15 cases of lung cancers with solitary lung nodules, were selected from the file. A pair of hard copies of original images and images reconstructed using type III compression was made for each case. Six radiologists evaluated the image quality by visual rating and receiver operating characteristic (ROC) curve analysis. For all five anatomic regions of normal cases, "original equal to compressed" was the most common response, followed by "original significantly better than compressed." When abnormal cases were evaluated for diagnostic information, there was no significant difference between the compressed and original images. ROC curve analysis on lung nodules with lung cancer showed no significant difference between the two. Compressed CR images using the type III irreversible technique are clinically applicable and acceptable despite slight degradation of image quality.

Adenocarcinoma↗

PubMed1998

[A case of emergency surgery for acute mitral regurgitation due to complete papillary muscle rupture as complication of acute inferior myocardial infarction].

We experienced a case with acute mitral regurgitation caused by complete posterior papillary muscle rupture as complication of acute inferior myocardial infarction, who underwent successfully emergency operation of mital valve replacement and coronary revascularization in acute stage. A 64-year-old woman developed sudden cardiogenic shock shortly after the onset of acute inferior myocardial infarction. The diagnosis of acute inferior myocardial infarction was based on the electrocardiographic findings. Under IABP support, preoperative coronary angiography visualized total occlusion of segment 3 of the right coronary artery, and preoperative left ventriculography showed akinesis of inferior wall and severe mitral regurgitation. At 6 hours after onset of papillary muscle rupture, emergency operation was performed. At operation, posterior papillary muscle was found to be totally ruptured. Coronary artery revascularization and mitral valve replacement were performed. Postoperative course was uneventful, with 4 days of IABP and 5 days of ventilatory support. She was discharged on the twentieth postoperative day in NYHA class I. Reports of successful emergency operation for total papillary muscle rupture following acute myocardial infarction are rare. Early diagnosis and surgical treatment are mandatory to save this group of patients.

Emergencies↗

PubMed1998

Surgical significance of supernumerary parathyroid glands in renal hyperparathyroidism.

In secondary hyperparathyroidism (2HPT) fundamentally all parathyroid glands, including supernumerary glands, become hyperplastic, and stimulation of parathyroid glands continues after parathyroidectomy (PTx). Therefore supernumerary glands have special significance during surgery for 2HPT, whether persistent or recurrent HPT. In the present study 570 patients underwent initial total PTx with a forearm autograft. The frequency, type, location, histopathology, and clinical significance of the supernumerary glands were evaluated. At the initial operation 90 supernumerary glands were removed from 82 to 570 patients (14.4%); 12 patients (2.1%) required extirpation of supernumerary glands for persistent/recurrent HPT. Altogether 104 supernumerary glands were identified at operation in 94 of the 570 patients (16.5%). Among these 104 glands, 25 (24.0%) were of the rudimentary, or split, type and 79 (76.0%) of the proper type. Supernumerary glands were most frequently identified in the thymic tongue (53/104, 51.0%); 32 (60.4%) of these 53 glands were identified only microscopically. In 6 of the 570 cases (1.1%), reoperation was required for persistent HPT due to supernumerary glands located in the mediastinum, and 6 patients underwent neck reexploration for recurrence. Histopathologically, 61 of 104 (58.7%) supernumerary glands, including 36 glands recognized only microscopically, showed diffuse hyperplasia, and 43 (41.3%) displayed nodular hyperplasia. Residual small supernumerary glands with diffuse hyperplasia have the potential to be transformed to nodular hyperplasia during long-term hemodialysis. Therefore all parathyroid glands including supernumerary glands should, if possible, be removed at the initial operation. Routine removal of the thymic tongue and careful examination of the regions surrounding the lower poles of the thyroid, especially on the left side, are important steps in the surgical treatment.

Adult↗

PubMed1998

A new inbred strain JF1 established from Japanese fancy mouse carrying the classic piebald allele.

A new inbred strain JF1 (Japanese Fancy Mouse 1) was established from a strain of fancy mouse. Morphological and genetical analysis indicated that the mouse originated from the Japanese wild mouse, Mus musculus molossinus. JF1 has characteristic coat color, black spots on the white coat, with black eyes. The mutation appeared to be linked to an old mutation piebald (s). Characterization of the causative gene for piebald, endothelin receptor type B (ednrb), demonstrated that the allele in JF1 is same as that of classic piebald allele, suggesting an identical origin of these two mutants. Possibly, classic piebald mutation was introduced from the Japanese tame mouse, which was already reported at the end of the 1700s. We showed that JF1 is a useful strain for mapping of mutant genes on laboratory strains owing to a high level of polymorphisms in microsatellite markers between JF1 and laboratory strains. The clarified genotypes of JF1 for coat color are "aa BB CC DD ss".

Alleles↗

PubMed1998

Teratoma of the tongue in neonates: report of a case and review of the literature.

A female newborn presented with a huge mass protruding from the mouth. She had no respiratory distress but had difficulty swallowing. The mass originated from the tongue and was completely extirpated on the day of birth. The histologic diagnosis was mature teratoma. Three days later, another mass measuring 1 cm in diameter was found attached to the upper pharyngeal wall and was also completely extirpated 20 days after birth. The histologic diagnosis was also mature teratoma. The infant had a complete cleft palate, but no other malformation was found. Two years after surgery there is no sign of recurrence.

Female↗

PubMed1998

Histological investigation of spinal cord lesions in the spinal hyperostotic mouse (twy/twy): morphological changes in anterior horn cells and immunoreactivity to neurotropic factors.

We examined the morphology of spinal accessory motoneurons and immunoreactivity to neurotrophins, brain-derived neurotropic factor (BDNF) and neurotrophin (NT)-3, as well as the presence of reactive astrocytosis in 70 tiptoe walking Yoshimura (twy) mice that develop calcification at C1-C2 vertebral level compressing the spinal cord. At the level of compression, the area of neuronal soma and total length of dendrites of wheat germ agglutinin-horseradish peroxidase (WGA-HRP)-labelled accessory motoneurons in the medial cell pool decreased significantly with decrement in motoneuron population, relative to the control. In contrast, at sites rostral to the compressive lesion, a significant enlargement of the neuron soma and dendritic elongation were noted, associated with increased motoneuron population and decreased transverse area of the cord at the level of compression. At this site, enhanced BDNF and NT-3 immunoreactivities were evident in the anterior horn cells. In mice with a more severe degree of compression, astrocyte-like cells showing BDNF immunoreactivity became abundant and axons in the anterior column demonstrated a marked NT-3 immunoreactivity. Our results suggest increased functional activity of anterior horn cells at levels rostra] to the site of compression. We speculate that the presence of BDNF and NT-3 in neurons and astrocyte-like cells is proportionate to the severity of chronic mechanical compression and may contribute to the heterotropic neuronal reserve and survival.

Animals↗

PubMed1998

Bile acid metabolism in analbuminemic rats.

The bile acid concentrations in the serum, liver, bile, intestines, and feces of 3- and 19-mon-old male and female Nagase analbuminemic (NA) rats were compared with those in Sprague-Dawley (SD) rats. There was no significant difference in the bile acid levels between NA and SD rats. However, increased biosynthesis and pool size of cholic acid (CD) derivatives and decreased levels of chenodeoxycholic acid (CDCA) derivatives (increased CA/CDCA ratio) were detected in male NA rats as compared to SD rats. The CA/CDCA ratio in female NA rats was not different from that in their SD counterparts. There were no significant differences between NA and SD rats in the biliary bile flow, bile acid levels in the small and large intestines, fecal bile acid excretion, bile acid concentration in the portal and systemic circulation, and in the pool size of bile acids. The blood lipid concentrations were significantly higher in the NA rats than in the SD rats. The hepatic levels of lipids were not significantly different between the two rat strains. In conclusion, this study showed that metabolism of bile acids in NA rats is not significantly affected, and that the hypercholesterolemia observed in these strains is not related to abnormalities of bile acid metabolism.

Animals↗

PubMed1998

Stabilities of N-acetyl-beta-D-glucosaminidase (NAG) isoenzymes in urine: advantage of NAG isoenzyme B measurement in clinical applications.

N-Acetyl-beta-D-glucosaminidase (NAG) is a widely used urinary enzyme for the assessment of renal diseases. We studied the stabilities of NAG isoenzymes in urine at 37 degrees C by enzyme assay and ELISA using a model simulating in vivo conditions. The stabilities were found to be affected by the pH. Under mild acidic condition (about pH 6), there was no significant loss of enzymatic activity of NAG isoenzyme A, enzymatic activity of NAG isoenzyme B and immunological activity of NAG isoenzyme B even after 8 h incubation. In contrast, under alkaline condition (about pH 8), the enzymatic activity of NAG isoenzyme A was rapidly lost, whereas both enzymatic and immunological activities of NAG isoenzyme B were maintained at more than 80% of their initial values. Also, we found that the ratios of endogenous NAG isoenzyme B to total NAG were elevated in alkaline urine samples. These results indicate that NAG isoenzyme A, which is a major isoenzyme in normal urine (pH 5-7), seems to be inactivated in alkaline urine. Our results suggest that for alkaline urine, NAG isoenzyme B should be measured to avoid misinterpretation of total NAG enzymatic activities.

Acetylglucosaminidase↗