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Biomedical subjects

Y Katayama

Publications and source records attributed to Y Katayama.

At least 343 records · Page 19Linked to original sources

Urinary type IV collagen as a marker for early diabetic nephropathy.

We investigated the urinary secretion of type IV collagen in 115 subjects with non-insulin-dependent diabetes mellitus (NIDDM) without macroproteinuria, 34 normal healthy subjects and 19 subjects with chronic glomerulonephritis (CGN). We examined the relation between the urinary level of type IV collagen and various clinical parameters. The urinary level of type IV collagen was significantly elevated in NIDDM subjects compared with normal subjects (4.88 +/- 3.12 vs. 1.7 +/- 1.25 micrograms/gCr, P < 0.001). The urinary level of type IV collagen was increased even in NIDDM subjects with normoalbuminuria. The ratio of urinary type IV collagen was significantly lower in subjects with chronic glomerulonephritis (CGN) than those in NIDDM subjects (P < 0.001), although there was no significant difference in the urinary level of type IV collagen between NIDDM and CGN subjects. The ratio of urinary type IV collagen to albumin was under 10.0 x 10(-6) in all subjects with CGN. Our results suggest that measurement of the urinary level of type IV collagen is useful for detection of early diabetic nephropathy and for the differential diagnosis of diabetic nephropathy and chronic glomerulonephritis.

Adult↗

Autoimmune hemolytic anemia in allergic granulomatous angitis (Churg-Strauss syndrome).

We describe a patient with allergic granulomatous angitis who developed autoimmune hemolytic anemia (AIHA). A 44-year-old male had been suffering from bronchial asthma. On admission, laboratory tests revealed the presence of severe eosinophilia (21,500/microliters), elevation of total immunoglobulin E (IgE), high lactic dehydrogenase (LDH) and low haptoglobin levels, in addition to moderate reticulocytosis. During admission, the patient showed almost simultaneous occurrence of vasculitis in the extremities, severe hemolysis and exacerbation of asthma in relation to the progression of eosinophilia. Both IgM and IgG autoantibodies were considered to be responsible for hemolysis. Interestingly, serum levels of interleukin-4 (IL-4) and IL-5 were increased in association with eosinophilia and increased IgE production. These findings suggest that the AIHA in this patient is mediated or enhanced at least partly by high IL-4 and IL-5 production. Although AIHA in this syndrome is very rare, it should be considered as a clinical manifestation.

Adult↗

Bisphosphonates act on osteoblastic cells and inhibit osteoclast formation in mouse marrow cultures.

We examined the mode of action of bisphosphonates on osteoclastic cell recruitment using mouse marrow cultures with or without osteoblastic cells. Tartrate-resistant acid phosphatase-positive multinucleated cells [TRAP(+)MNC] formed in cultures were determined to be osteoclastic cells. In marrow cultures, TRAP(+) MNC formation in the presence of 10(-8) mol/L 1,25(OH)2D3 was not affected by the addition of 10(-6) mol/L dihydrogen (cycloheptylamino)-methylenebisphosphonate monohydrate (YM175). However, it was inhibited in cocultures of marrow cells with osteoblastic cells. The inhibitory effect was evident throughout the entire culture period. YM175 dose dependently inhibited TRAP(+) MNC formation, and other bisphosphonates--pamidronate and alendronate--also inhibited TRAP(+) MNC formation in the coculture. Similar observations were also made in the coculture of spleen cells with osteoblastic cells. The conditioned media of osteoblastic cells treated with 10(-6) mol/L YM175 inhibited TRAP(+) MNC formation in marrow cultures. The presence of YM175 in methylcellulose cultures affected neither the colony formation of monocyte-macrophage lineage, nor TRAP(+) MNC formation in the succeeding cocultures of recovered cells with osteoblastic cells. These results indicate that YM175 and probably other bisphosphonates as well preferentially inhibit the later stage of osteoclastogenesis through its action on osteoblastic cells. Our findings suggest that part of the inhibitory action by osteoblastic cells in the presence of bisphosphonates is mediated through soluble factor(s).

Acid Phosphatase↗

Androgen therapy in combination with granulocyte colony-stimulating factor and erythropoietin in a patient with refractory anemia.

Initial treatment with androgen (metenolone acetate) alone for 19 weeks had no effect in a 45-year-old Japanese female with refractory anemia (RA). The patient achieved trilineage hematologic recovery after addition of recombinant human granulocyte colony-stimulating factor (G-CSF) and recombinant human erythropoietin (Epo) to the androgen therapy. Anemia progressed after the cessation of metanolone acetate, but was effectively treated by the readministration of metenolone acetate. Thus, the androgen therapy in combination with hematopoietic growth factors such as G-CSF and/or Epo may be effective in patients with RA.

Anemia, Refractory↗

Carinal reconstruction under veno-venous bypass using a percutaneous cardiopulmonary bypass system.

We report two patients who underwent carinal resection and reconstruction for advanced lung cancer under veno-venous bypass. The bypass system consisted of a centrifugal pump and a hollow-fiber membrane oxygenator, and was established by percutaneous insertion of cannulas through the femoral veins using the Seldinger technique. This respiratory support system under veno-venous bypass was safe and useful for carinal reconstruction, providing a good visual field and adequate oxygenation. Although other standard accepted ventilation techniques can be used for carinal resection, veno-venous bypass is an alternative adjunct in cases involving difficult carinal reconstruction.

Carcinoma, Squamous Cell↗

Alterations in the biosynthesis of lignin in transgenic plants with chimeric genes for 4-coumarate: coenzyme A ligase.

The introduction of chimeric sense and antisense gene constructs for 4-coumarate:coenzyme A ligase into tobacco plants caused the reduction of the 4CL activity in the transgenic plants. In the transgenic plants, the cell walls of the xylem tissue in stems were brown and the molecular structure of lignin in the colored cell walls was dramatically different from that in the control plants. Analysis with different types of stain revealed that levels of cinnamyl aldehyde residues and syringyl units in lignin were depressed in the brownish cell walls. Furthermore, the lignin content in colored tissue was lower than that in the normal tissue. Our results indicate that 4CL has important roles in the determination of the composition and the amount of lignin in tobacco plants.

Blotting, Northern↗

Residual radioactivity in the soil of the Semipalatinsk Nuclear Test Site in the former USSR.

This paper deals with our efforts to survey residual radioactivity in the soil sampled at the Semipalatinsk Nuclear Test Site and at off-site areas in Kazakhstan. The soil was sampled at the hypocenter where the first Soviet nuclear explosion was carried out on 29 August 1949, and at the bank of the crater called "Bolapan," which was formed by an underground nuclear detonation on 15 January 1965 along the Shagan River. As a comparison, other soil was also sampled in the cities of Kurchatov and Almaty. These data have allowed a preliminary evaluation of the contemporary radioactive contamination of the land in and around the test site. At the first nuclear explosion site and at Bolapan, higher than background levels of 239,240Pu with weapons-grade plutonium were detected together with fission and activation products such as 137Cs, 60Co, 152Eu, and 154Eu.

Gamma Rays↗

Rhodothermus obamensis sp. nov., a modern lineage of extremely thermophilic marine bacteria.

A novel extremely thermophilic bacterium was isolated from a shallow marine hydrothermal vent environment (depth, 22 m) in Tachibana Bay, Nagasaki Prefecture, Japan. The cells of this organism were gram-negative rods. Growth occurred at temperatures between 50 and 85 degrees C (optimum temperature, 80 degrees C; doubling time at optimum temperature, 90 min), at pH 5.5 and 9.0 (optimum pH, 7.0), and in the presence of 1 and 5% NaCl (optimum NaCl concentration, 3%). The new isolate was an aerobic heterotroph which utilized the following compounds as sole energy and carbon sources: yeast extract, peptone, starch, casein, Casamino Acids, a variety of sugars, some carboxylic acids, and amino acids. As determined by a sequence analysis of the 16S rRNA, the new isolate belongs to the genus Rhodothermus and represents a modern lineage of extreme thermophiles within the domain Bacteria. On the basis of the physiological and molecular properties of the new isolate, we describe a new species, Rhodothermus obamensis. The type strain of R. obamensis is strain OKD7 (= JCM 9785).

Base Sequence↗

Genotype analysis of hepatitis C virus among blood donors and inmates in Metro Manila, The Philippines.

Antibodies against hepatitis C virus (HCV) were detected in 18 (2.3%) of 800 sera from commercial blood donors and 23 (4.6%) of 502 sera from inmates in Metro Manila, the Philippines. The difference in the antibody prevalence between the two groups was statistically significant (P < 0.05). HCV RNA was detected in 14 (78%) of the 18 antibody-positive sera from blood donors and 19 (83%) of the 23 antibody-positive sera from inmates. Genotype analysis revealed that HCV-2a (7%). Among inmates, on the other hand, HCV-1a (68%) was most common, followed by HCV-1b (11%), HCV-2a (5%) and HCV-2b (5%). Overall, HCV-1a and HCV-1b appeared to be predominant among them. Thus, the genotype prevalence in the Philippines was distinct from those in other Southeast Asian countries such as Thailand, Vietnam and Indonesia, and also distinct from those in the Far East including Taiwan, Mainland China and Japan.

Asia, Southeastern↗

Small-cell neuroendocrine carcinoma of the uterine cervix associated with micro-invasive squamous cell carcinoma and adenocarcinoma in situ.

A case of small-cell neuroendocrine carcinoma of the uterine cervix associated with squamous cell carcinoma and adenocarcinoma in situ is reported. The tumor consisted mainly of uniform small cells with a population of intermediate cells that resembled carcinoid tumor cells. Foci of micro-invasive squamous cell carcinoma and adenocarcinoma in situ were recognized separately, adjacent to the main tumor. Both Grimelius stain and immunostaining of serotonin were positive for small-cell and intermediate-cell carcinoma. Neurosecretory granules were demonstrated by electron microscopy. Microacini with positive mucin staining and microvilli-like structures suggested glandular or exocrine differentiation of the tumor. Three distinctive types of differentiation, neuroendocrine, exocrine and squamous characteristics, were expressed in the tumor.

Adenocarcinoma↗

Differential prevalence of hepatitis C virus subtypes in healthy blood donors, patients on maintenance hemodialysis, and patients with hepatocellular carcinoma in Surabaya, Indonesia.

Determination of the prevalence of liver disease caused by hepatitis C virus (HCV) of various genotypes helps provide an understanding of the virulences of these genotypes. Differences in the prevalences of these genotypes are known to exist in the various geographical regions of the world. Hence, we performed seroepidemiological and molecular epidemiological analyses of HCV in Surabaya, Indonesia. The prevalences of anti-HCV antibodies were 2.3, 76.3 and 64.7% in healthy blood donors, patients on maintenance hemodialysis, and patients with hepatocellular carcinoma (HCC), respectively. HCV-2a was the most common (52%) among the HCV clones obtained from blood donors; this was followed by HCV-1b (15%), HCV-1a (7%), and HCV-1d (7%), a unique Indonesian subtype. The high prevalence of HCV-2a in blood donors was further supported by serotyping analysis that could discriminate HCV type 2 (HCV-2a and -2b) from HCV type 1 (HCV-1a, -1b, and -1d). HCV-1a, -1b, and -1d were strongly associated with elevated serum alanine aminotransferase (ALT) levels in blood donors, suggesting a possibly more pathogenic feature of those subtypes than HCV-2a. In patients on maintenance hemodialysis, HCV-1a and -1b (each 31%) were among the most common subtypes, and in contrast to the case with blood donors, HCV-1a, -1b, and -1d were found in those with normal ALT as well as those with elevated ALT levels. Impaired immune responses of hemodialyzed patients might be responsible for the apparently decreased hepatocytic injury caused by infection with HCV type 1. In patients with HCC, HCV-1b (57%) was the most common; this was followed by HCV-1d (19%) and HCV-2a (5%). Subtype prevalence was not different between HCC patients with advanced liver cirrhosis and those without advanced cirrhosis.

Blood Donors↗

Isolation and analysis of cinnamic acid 4-hydroxylase homologous genes from a hybrid aspen, Populus kitakamiensis.

Cinnamic acid 4-hydroxylase (CA4H) is the second enzyme involved in phenylpropanoid biosynthesis and is a member of the cytochrome P-450 superfamily. Three CA4H homologous genes, cyp73A, cyp73b, and cyp73c, and a cDNA clone of cyp73a were isolated from a genomic library and a cDNA library of a hybrid aspen; Populus kitakamiensis, and were characterized. They might be interrupted by two introns each. cyp73a and cyp73b were very similar to each other not only in coding regions but also in non-coding regions. Southern blot analysis showed that four homologous genes for CA4H constructed a small gene family in the diploid genome of P. kitakamiensis. In the promoter regions, there were many common cis-element-like sequences in phenylpropanoid biosynthesis genes.

Amino Acid Sequence↗

[Effect of duration of cerebral ischemia on pyruvate dehydrogenase activity (PDH) and metabolites in the gerbil brain].

Pyruvate dehydrogenase (PDH) is one of the mitochondrial enzymes which regulate the glucose metabolism. The purpose of this study is to determine the effect of the duration of cerebral ischemia on PDH activity and the metabolites. Cerebral ischemia was produced by bilateral common carotid artery occlusion in Mongolian Gerbils. 20-minute (1) and 60-minute ischemic groups (2) were made. PDH activity and energy metabolites (ATP, PCr, lactate) were measured in the caudate nucleus and cortex at each time period. 1) 20 min ischemic group: PDH activity significantly increased after 20-min ischemia in both the caudate nucleus and cortex, and decreased to levels less than that of the control after 20 min reperfusion. At 60 and 120 min reperfusion, PHD activity returned to the control levels. ATP and PCr concentrations were significantly depleted after the ischemic insult, returning to 60-80% of the control level after reperfusion. Lactate concentrations increased significantly after ischemia, and were reduced by reperfusion. 2) 60 min ischemic group: PDH activity significantly increased after 60 min ischemia, and decreased but remained higher than the control level after 20 min reperfusion. At 60 and 120 min reperfusion, PDH activity gradually decreased towards control levels. ATP and PCr concentrations were depleted after ischemia, and were gradually restored after 20 min reperfusion, recovering to 50% after 60 min reperfusion. Lactate concentrations increased after the ischemic insult, and became more elevated after reperfusion. These findings indicate that there is a significant difference in the PDH activity and metabolism depending on the duration of ischemia. The data suggest that impaired metabolism and persistent elevation of PDH activity may be caused by damage to the mitochondria allowing the influx of Ca2+ during prolonged ischemia.

Adenosine Triphosphate↗

[Ischemic neuronal damage in early recovery. A morphological study on evolution of damage in hyperglycemia and normoglycemia].

The evolution of neuronal damage in various regions during ischemia and in early recovery was investigated morphologically using hyperglycemic and normoglycemic Wistar rats. Hyperglycemia (20-35 mu mol/ml plasma) was achieved with the infusion of glucose (i.v.) prior to ischemia. Forebrain ischemia (10 minutes) was induced by bilateral common carotid artery occlusion and hypotension. Normoglycemic rats were fasted prior to ishcemia. Ischemic changes of neurons were quantified by a five-point scale in the caudoputamen (CPu), globus pallidus (GP), hippocampus CA 1 (CA 1), parietal cortex (Par), and substantia nigra reticulata (SNR) during ishcemia and for 90 minutes after recirculation. In the hyperglycemic group, (1), CPu, CA 1 and Par; severely damaged neurons were seen at 60-90 minutes after recirculation. (2) GP; there was little neuronal damage. (3) SNR; immediately after recirculation damaged neurons were observed, and more damage was observed at 90 minutes post recirculation. In the normoglycemic group, no prominent neuronal damage was observed in any region. Hyperglycemia exacerbated ischemic neuronal damage after reperfusion. The evolution of neuronal damage was similar in the CPu and Par regions, but was different in the GP and SNR regions.

Animals↗

[Indications of parathyroidectomy for bone disease associated with secondary hyperparathyroidism].

BACKGROUND: The indications and suitable operative time of parathyroidectomy for secondary hyperparathyroidism were discussed. METHODS: From October 1978 to September 1994 parathyroidectomy was performed for 71 patients who had bone and/or joint pain due to secondary hyperparathyroidism. There were 37 men and 34 women (mean age 48.4 years). The duration of dialysis treatment before parathyroidectomy was 0.8 to 19 years, with a mean of 10.9 years. RESULTS: Postoperative subjective improvement was noted in 69% of the patients. No significant difference was observed between the improved and non-improved groups regarding age and the duration of dialysis treatment. But the improvement rate in female patients was significantly lower than that in male patients. CONCLUSION: Patients with high carboxyl-terminal PTH level and generalized fibrous osteitis were good suitable objects for parathyroidectomy. But, those with high serum aluminum level were unsuitable objects for it. Furthermore, 99mTc-Pyrophosphate bone scintigraphy and bone mineral determination using dual photon absorptiometry (DPA) or dual energy X-ray absorptiometry (DEXA) were proved to be valuable for patient selection for parathyroidectomy.

Adult↗

Low-dose melphalan for treatment of high-risk myelodysplastic syndromes.

Twenty-one consecutive patients with high-risk myelodysplastic syndromes (MDS) including six with refractory anemia with excess blasts (RAEB) and 15 with RAEB in transformation (RAEBt) were treated with daily oral low-dose melphalan (2 mg/day). Seven patients achieved complete remission (CR), one patient partial response, and four minor response while the remaining eight did not respond. The median age of the patients was 65 (range 56-83 years). The mean total amount of melphalan given was 140+/-19 mg in patients who achieved CR. The median duration of CR was 14.5 months. Serious toxicity was not encountered in any of the cases. Neither marrow suppression nor pancytopenia was observed during the administration of melphalan in patients who achieved CR. The clinical features of CR patients included normal karyotype and hypocellular marrow in biopsied specimen from the lilac bone. These observations suggest that melphalan may exert some differentiation effects on leukemic cells in addition to cytotoxic effects. Our study indicates that daily administration of low-dose melphalan is worth trying in the treatment of elderly patients with high-risk MDS.

Aged↗

[A case of pulmonary dirofilariasis].

A 41-year-old man was admitted to the hospital for detailed evaluation of chronic hepatitis C. A nodular shadow (15 x 15 mm) was detected in the left middle lung field on a chest X-ray film. Roentgenologic, cytologic, and bronchial endoscopic examinations resulted in no definitive diagnosis. To rule out a malignant tumor the left lung was partially resected (S6). Histological examination of the resected specimen revealed Dirofilaria worms in a necrotic mass. In most cases of pulmonary dirofilariasis, thoracotomy is done to confirm the diagnosis. Recently, however, antibodies against Dirofilaria have been detected by immunologic methods and have been used to help make the diagnosis in some cases. A less invasive procedure, such as a reliable immunologic test or a technique for thoracoscopic resection, would be very useful in cases of this benign condition.

Adult↗