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Biomedical subjects

K Tsuchiya

Publications and source records attributed to K Tsuchiya.

At least 127 records · Page 7Linked to original sources

Validity of cadmium concentration in rice as the "dose" of the dose-response relationship between cadmium intake and renal dysfunction.

It is well known that cadmium (Cd) causes renal dysfunction such as increase of beta(2)-microglobulin excretion into urine. Although Cd in rice seems to be one of the largest sources of total Cd intake in Japan, there are very few studies that have epidemiologically clarified the relationship between Cd concentration in rice (Cd-R) and renal dysfunction, because such studies are basically ecological studies, in which confounding factors are difficult to take into consideration. To derive safety levels for foodstuff from Cd-R, it is essential to evaluate the effect of confounding factors. Thus, we investigated the dose-response relationship between renal dysfunction and not only Cd-R but also confounding factors, and we tried to determine whether Cd-R is an adequate indicator of "dose" in the dose-response relationship between Cd intake and renal dysfunction. In 1971, Cd-R data were obtained from rice samples collected by the Environment Agency, Government of Japan in the Fuchu area of Toyama Prefecture, which is known as a place where many itai-itai disease patients were found, and medical data were collected during 1979-1984 by Toyama Prefecture. First, the dose-response relationship between Cd-R and renal dysfunction was analyzed using the data from the Fuchu area. Second, to investigate the effect of confounding factors, analysis using the data from both the Fuchu area and an unpolluted area with environmental factors different from those of the Fuchu area was performed. The results showed that the cause of renal dysfunction could not be explained by Cd-R alone, and confounding factors were not negligible. Although it is difficult to clarify precisely the confounding factors from the available data, it is concluded that deriving a safety level for foodstuffs using only the Cd-R level as a reference is not appropriate.

Aged↗

A molecular phylogenetic framework for the Ryukyu endemic rodents Tokudaia osimensis and Diplothrix legata.

Diplothrix legata and Tokudaia osimensis are rodent species endemic to the Ryukyu Islands (Okinawa area) of the southern part of Japan. To place them within a phylogenetic framework of Asian rodent species, we examined the molecular relationships among these species and Apodemus, Micromys, Mus, and Rattus, using an analysis of mitochondrial cytochrome b gene (1140 bp) and nuclear IRBP gene (782 bp) sequences. The results indicate that the four main murine genera and Tokudaia diverged at similar evolutionary times, namely at the time of the radiation of Murinae, 14 to 40 million years ago, depending on different concepts for the divergence times of Rattus and Mus. In contrast, Diplothrix separated from the Rattus group more recently. Our results indicate that D. legata and the Rattus group diverged at 20-30% of the divergence time of Rattus and Mus under the assumption of the molecular clock, suggesting that D. legata established its lineage at least by the beginning of the Pleistocene era. It is thus evident that the Okinawa area preserves rare indigenous species with various levels of genetic endemicity.

Animals↗

Penetrating knife injury to the heart.

A 39-year-old man attempted to kill himself using a small knife to penetrate the left anterior chest wall because of trouble at work and with his girlfriend. On arrival at the emergency room, his consciousness was not clear and vital signs were unstable. The knife remained vertically located in the left anterior chest wall. A large left hemothorax was identified by chest X-ray, and moderate cardiac tamponade was detected by echocardiography. Left-sided chest drainage was performed by inserting a chest drainage tube, and about 2500 ml of hemorrhagic effusion was drained. An emergency operation was performed to relieve the cardiac tamponade and repair the penetrating cardiac injury. About an hour after arrival at the emergency room, a median sternotomy was performed in the operating room. The knife had injured the surface of the right ventricular outflow tract, the left lung, and the 3rd intercostal artery and vein. Cardiopulmonary bypass was immediately prepared for the repair of the cardiac injury. The wounds were successfully repaired with pledgeted sutures under cardiac beating. The postoperative course was uneventful with no sign of infection. The patient was discharged at 9 days after the operation. Here we have reported a case of successful surgical repair of a penetrating knife injury to the heart, which was managed by immediate resuscitation and emergency surgery.

Adult↗

Surgical repair of postinfarction ventricular septal rupture.

OBJECTIVES: Postinfarction ventricular septal rupture is fatal without surgical repair because of heart failure and secondary multiple organ failure. We investigated surgical results of postinfarction ventricular septal rupture and discussed the surgical strategy of postinfarction ventricular septal rupture. METHODS: Twelve patients (mean age 71.3 +/- 7.4 years, with range from 61 to 81 years) underwent surgical repair of postinfarction ventricular septal rupture, from 1990 to 1998 in our Institute. There were 6 women and 6 men. The ventricular septal rupture was anterior in 10 patients and inferior in 2. The operative technique for anterior ventricular septal rupture was reconstruction of the septum with a Dacron patch after infarctectomy, according to the method of Daggett et al. For posterior ventricular septal rupture, reconstruction of the septum with a Dacron patch after infarctectomy was performed and the ventricular incision was closed with a two-layer patch. Coronary artery bypass grafting was performed in 5 patients for severe proximal coronary artery stenosis using saphenous vein grafts. RESULTS: Overall hospital mortality was 0%. A postoperative residual shunt was recognized in 3 patients, but all were well-controlled conservatively and re-operation was not needed. The patients have been followed up for a mean of 59.5 months. There have been two late deaths due to non-cardiac problems. Acturial survival rate for the 12 patients was 90% at 1 year and 75% at 5 years. CONCLUSIONS: The Daggett method is simple and fast, and is an effective and reliable technique for the repair of ventricular septal rupture.

Aged↗

Aneurysms in the ascending aorta adherent to the sternum after cardiac surgery.

Sternotomy in a patient with an aneurysm in the ascending aorta adherent to the sternum after cardiac surgery can result in fatal hemorrhage or brain damage unless the distal ascending aorta can be identified and secured immediately. A left anterolateral thoracotomy was used in three patients with adherent aneurysms. The distal ascending aorta was isolated, and dissection was performed between the aneurysm and the sternum. There was no complication. This method was safe, and blood loss was minimized.

Adult↗

Rapidly progressive aphasia and motor neuron disease: a clinical, radiological, and pathological study of an autopsy case with circumscribed lobar atrophy.

This report concerns an autopsy case of rapidly progressive aphasia and motor neuron disease. The patient was a Japanese woman who was 75 years old at the time of death. The family history did not reveal hereditary burden. She developed language disturbances and difficulty in swallowing at age 74. Neurological examination 1 month after the disease onset revealed motor aphasia without dementia and bulbar sign, followed by muscle weakness of the four extremities. Neuroradiological examination revealed progressive atrophy of the anterior part of the left temporal lobe. She died of respiratory difficulty 10 months after the disease onset. Macroscopically, neuropathological examination showed circumscribed atrophy of the left perisylvian region and, histologically, neuronal loss in the cerebral cortex, including the primary motor area, substantia nigra, brain stem motor nuclei, and anterior horns of the spinal cord, in addition to obvious degeneration of the pyramidal tracts and presence of Bunina bodies. Ubiquitin-immunoreactive neuronal inclusions were present in the hippocampal dentate granular cells and frontotemporal cortical layer II neurons. Based on these clinicopathological findings and a review of the literature, we concluded that our case is the first reported case of amyotrophic lateral sclerosis with dementia that clinically showed rapidly progressive aphasia.

Aged↗

The cerebellar and thalamic degeneration in Fukuyama-type congenital muscular dystrophy.

We report a male autopsy case of Fukuyama-type congenital muscular dystrophy (FCMD), with unusual neuropathological findings. The patient was a Japanese man aged 26 years at the time of death. He had shown severe psychomotor retardation and muscular dystrophy since early infancy, and was diagnosed as having FCMD at the age of 5 years. He died of respiratory failure. The main neuropathological finding was extensive cerebral and cerebellar cortical dysplasia, characteristic of this disorder. In addition, degeneration of the cerebellar efferent pathway, including the dentate nucleus, superior cerebellar peduncle, and red nucleus, and that of the lateral thalamic nucleus were observed. These findings suggest the possibility that the long survival can clarify the latent neurodegeneration in the cerebellum and thalamus in FCMD, in addition to congenital malformations. The system degeneration should be carefully evaluated in the pathological examination of this disorder.

Adult↗

Familial amyotrophic lateral sclerosis with onset in bulbar sign, benign clinical course, and Bunina bodies: a clinical, genetic, and pathological study of a Japanese family.

We report a Japanese family with autosomal dominant adult-onset amyotrophic lateral sclerosis (FALS) with onset in the bulbar musculature, clinically benign course, absence of the Cu/Zn superoxide dismutase-1 (SOD 1) gene mutation, and many Bunina bodies, in addition to involvement of the upper and lower motor neurons. The proband was a Japanese woman who was 66 years old at the time of death. Family history disclosed five patients with FALS over three generations. She developed dysarthria at age 57, followed by dysphagia, muscle weakness of the upper extremities, and difficulty in respiration. She could walk without support until her death. The elder sister of the proband developed dysarthria at age 48 and died at age 58. A genetic study of the nephew of the proband showed the absence of a mutation in the SOD 1 gene. Neuropathological examination of the proband disclosed neuronal loss in the upper and lower motor neurons, and numerous Bunina bodies in the lower motor neurons without Lewy body-like inclusions or ubiquitin-immunoreactive neuronal inclusions. No degeneration of the Clarke's column, middle root zone of the posterior column, or posterior spinocerebellar tract was present. Review of the literature revealed that only patients with FALS with a long survival period of over 5 years had pathological findings consistent with FALS with posterior column involvement. This study contributes to the elucidation of the clinicopathological heterogeneity of FALS.

Aged↗

Constant involvement of the Betz cells and pyramidal tract in multiple system atrophy: a clinicopathological study of seven autopsy cases.

We investigated clinicopathologically the pyramidal signs, including spasticity, hyperreflexia, and Babinski's sign, and the involvement of the pyramidal tract and primary motor cortex, in seven Japanese autopsy cases of multiple system atrophy (MSA). Pyramidal signs were observed in six (86%) of the seven autopsy cases. Hyperreflexia and Babinski's sign were each evident in five patients, but spasticity was observed in only one patient. Loss of Betz cells and presence of glial cytoplasmic inclusions in the primary motor cortex were noticed in all seven cases. Astrocytosis in the fifth layer of the primary motor cortex was noticed in five cases, but its presence was not related to the duration of the disease. Involvement of the pyramidal tract in the spinal cord, particularly of the small myelinated fibers, was observed in all seven cases, but no involvement of the pyramidal tract in the midbrain was evident in any of the six cases in which this structure was examined. In MSA, pyramidal signs were shown to be present more frequently than believed before, and the clinicopathological correlation between pyramidal signs and involvement of the pyramidal tract was obvious. Constant involvement of Betz cells in MSA has not been reported. Our clinicopathological findings may also make a contribution to the understanding of the clinicopathological hallmarks of MSA.

Female↗

Adaptive modification of membrane phospholipid fatty acid composition and metabolic thermosuppression of brown adipose tissue in heat-acclimated rats.

Thermogenesis, especially facultative thermogenesis by brown adipose tissue (BAT), is less important in high ambient temperature and the heat-acclimated animals show a lower metabolic rate. Adaptive changes in the metabolic activity of BAT are generally found to be associated with a modification of membrane phospholipid fatty acid composition. However, the effect of heat acclimation on membrane phospholipid fatty acid composition is as yet unknown. In this study, we examined the thermogenic activity and phospholipid fatty acid composition of interscapular BAT from heat-acclimated rats (control: 25+/-1 degrees C, 50% relative humidity and heat acclimation: 32+/-0.5 degrees C, 50% relative humidity). Basal thermogenesis and the total thermogenic capacity after noradrenaline stimulation, as estimated by in vitro oxygen consumption of BAT (measured polarographically using about 1-mm(3) tissue blocks), were smaller in the heat-acclimated group than in the control group. There was no difference in the tissue content of phospholipids between the groups when expressed per microgram of DNA. The phospholipid fatty acid composition was analyzed by a capillary gas chromatograph. The state of phospholipid unsaturation, as estimated by the number of double bonds per fatty acid molecule, was similar between the groups. The saturated fatty acid level was higher in the heat-acclimated group. Among the unsaturated fatty acids, heat acclimation decreased docosahexaenoic acid and oleic acid levels, and increased the arachidonic acid level. The tissue level of docosahexaenoic acid correlated with the basal oxygen consumption of BAT (r=0.6, P<0.01) and noradrenalinestimulated maximum values of oxygen consumption (r=0.5, P<0.05). Our results show that heat acclimation modifies the BAT phospholipid fatty acids, especially the n-3 polyunsaturated fatty acid docosahexaenoic acid, which is possibly involved in the metabolic thermosuppression.

Adaptation, Physiological↗

Esophageal intramural pseudodiverticulosis associated with esophageal perforation.

We report a rare case of esophageal intramural pseudodiverticulosis with lower esophageal stricture which perforated into the peritoneal cavity after the patient vomited. A 61-year-old man was admitted with severe chest and epigastric pain after dysphagia and vomiting. Under a diagnosis of upper gastrointestinal perforation, laparotomy was performed. The anterior wall of the abdominal esophagus was found to have ruptured, and proximal gastrectomy with abdominal esophagectomy was performed. Histological examination revealed esophageal intramural pseudodiverticulosis with esophageal stricture distal to the site of rupture, and postoperative endoscopy showed diffuse pseudodiverticulosis in the remaining esophagus. The patient is free of symptoms 5 years after the surgery. This case suggests that careful treatment may be indicated in patients with esophageal intramural pseudodiverticulosis with stricture and elevated intraluminal pressure, to minimize the possibility of severe complications such as esophageal perforation.

Diverticulum, Esophageal↗

Tumor-targeted chemotherapy with SMANCS in lipiodol for renal cell carcinoma: longer survival with larger size tumors.

OBJECTIVES: To evaluate the anticancer effects of a lipophilic macromolecular anticancer agent, poly(styrene-co-maleic acid)-conjugated neocarzinostatin (SMANCS), dissolved in a lipid contrast medium (Lipiodol) given via the renal artery to patients with renal cell carcinoma. METHODS: Among 467 patients with renal cell carcinoma treated between April 1984 and March 1993, 191 were treated with SMANCS dissolved in a lipid contrast medium (a 3:2 mixture of Lipiodol F and Lipiodol Ultrafluid; Lpd). Selective arterial infusion of SMANCS/Lpd was performed at a dose of 1.0 or 1. 5 mg/mL. The infusion was repeated at intervals of about 2 weeks or longer, but the doses and the total number of infusions varied among patients, according to results of computed tomography analysis. RESULTS: Statistical analysis was performed for 415 patients who met the criteria of this study. Twenty-six surgical patients with metastases who underwent infusion therapy of SMANCS/Lpd for primary lesions showed 3 and 5-year survival rates of 23.0% and 12.8%, respectively; the rates were 19.3% and 9.7% in 31 patients who did not receive SMANCS infusion therapy. In 125 surgical patients without metastases who underwent SMANCS/Lpd infusion, the 5 and 10-year survival rates were 83.0% and 75.2%, respectively, whereas rates of 84.6% and 78.9% were observed in 199 surgical patients whose median tumor size was significantly smaller, however, than the SMANCS/Lpd infusion group. The maximal tumor diameter at the beginning of treatment was significantly larger (mean diameter 70.8 mm) in the SMANCS/Lpd infusion group than in the noninfusion group (59.1 mm). The survival rate was statistically better for patients with tumors of 100 mm diameter or larger in the SMANCS/Lpd infusion group (P <0.05): 5 and 10-year survival rates were 70.4% and 61.6%, respectively, for the infusion group and 64.6% and 50.9% for the group receiving no drug. In patients with larger tumor (greater than 110 mm), the survival rate at 13 years was 75% in the SMANCS/Lpd infusion group and 0% in the surgery group. CONCLUSIONS: Arterial infusion therapy with SMANCS/Lpd appears to be effective for large renal cell carcinoma without metastases in conjunction with surgery.

Adolescent↗

Isolation and characterization of free radical scavenging flavonoid glycosides from the flowers of Spartium junceum by activity-guided fractionation.

Spartium junceum L. (Fabaceae) flowers are used for the treatment of peptic ulcers in Turkish folk medicine. The possible superoxide dismutase-like activity of the extracts, fractions and constituents obtained through activity-guided fractionation were studied by using in vitro electron spin resonance spectrometry, in order to explain the role of antioxidant principles in the potent antiulcerogenic activity of the extract. Despite the fact that the triterpene, spartitrioside, which was previously reported as the active antiulcerogenic constituent of the flowers was found almost inactive, the flavonoid-rich fractions showed potent antioxidant activity. Five flavonoid glycosides bearing catechol structure in ring B were isolated from the butanol extract and their structures were elucidated using 1H- and 13C-NMR techniques as isoquercitrin (quercetin 3beta-glucoside) (1,); luteolin 4'beta-glucoside (2); quercetin 3, 4'-diglucoside (3); azaleatin 3beta-glucoside (quercetin 5-methylether 3beta-glucoside) (4), quercetin 4'beta-glucoside (5). Flavonoids (2) and (4) showed the highest in vitro antioxidant activity with 22.59 and 19.08 U/ml, respectively.

Electron Spin Resonance Spectroscopy↗

A phylogenetic view on species radiation in Apodemus inferred from variation of nuclear and mitochondrial genes.

Species of field mice (genus Apodemus) are the most common rodents inhabiting woodlands and forests of the Palaearctic region. We examined the cytochrome b (cyt b) gene in mitochondrial DNA (1140 bp) and the interphotoreceptor retinoid binding protein (IRBP) gene in nuclear DNA (1152 bp) in nine species of Apodemus. Based on the genetic variation, the nine species were grouped into four lineages: (1) Agrarius group (A. agrarius, A. peninsulae, A. semotus, and A. speciosus), (2) Argenteus group (A. argenteus), (3) Gurkha group (A. gurkha), and (4) Sylvaticus group (A. alpicola, A. flavicollis, and A. sylvaticus). It was shown that these four lineages diverged within a short period of evolutionary time, suggestive of a radiation event. Soon after the radiation, the Agrarius group was likely to have differentiated again into the species lineages simultaneously. In contrast, the European clade, the Sylvaticus group, radiated rather recently. The relative ratio of the extent of sequence divergence among the four main lineages to that among the members of the subfamily Murinae (including Mus and Rattus) was calculated to be 72.4% in the cyt b gene with transversional substitutions, and 58.5% in the IRBP gene with all substitutions, using the Kimura two-parameter method. The value for the three European lineages was 27.6% in the cyt b gene and 12.3% in the IRBP gene. These results may have a correlation with the notion that deciduous broadleaf forests remained in Central East Asia through the late Tertiary to the present, while those in Europe to a large extent had disappeared by the Pliocene.

Animals↗

A lipochito-oligosaccharide, Nod factor, induces transient calcium influx in soybean suspension-cultured cells.

Lipochito-oligosaccharides (Nod factors) produced by Rhizobium or Bradyrhizobium are the key signal molecules for eliciting nodulation in their corresponding host legumes. To elucidate the signal transduction events mediated by Nod factors, we investigated the effects of Nod factors on the cytosolic [Ca2+] of protoplasts prepared from roots and suspension-cultured cells of soybean (Glycine max and G. soja) using a fluorescent Ca2+ indicator, Fura-PE3. NodBj-V (C18:1, MeFuc), which is a major component of Nod factors produced by Bradyrhizobium japonicum, induces transient elevation of cytosolic [Ca2+] in the cells of soybean within a few minutes. This effect is specific to soybean cells and was not observed in the tobacco BY-2 cells. Furthermore, NodBj-V without MeFuc did not induce any cytosolic [Ca2+] elevation in soybean cells. Exclusion of Ca2+ from the medium, as well as pre-treatment of the cells with an external Ca2+ chelator or with a plasma membrane voltage-dependent Ca2+ channel inhibitor, suppressed the Nod factor-dependent cytosolic [Ca2+] elevation. These results indicate that transient Ca2+ influx from extracellular fluid is one of the earliest responses of soybean cells to NodBj-V (C18:1, MeFuc) in a host-specific manner.

Bradyrhizobium↗

Glomerular expression of endothelial nitric oxide synthase in deoxycorticosterone acetate-salt-treated rats.

1. In the present study, we investigated the relationship between chronic volume loading and glomerular endothelial nitric oxide synthase (eNOS) expression. Immunohistochemical expression of eNOS in glomeruli was semiquantified by graded scores of staining intensity. Each glomerulus was isolated by microdissection and mRNA expression was detected by reverse transcription-polymerase chain reaction (RT-PCR) in desoxycorticosterone acetate (DOCA)-salt-treated rats. 2. Glomerular expansion and dilatation of tubules were the main histological findings and glomerular and vascular injury scores were significantly higher in the DOCA-salt-treated group than in the control group. Endothelial NOS staining in glomeruli in DOCA-salt-treated animals was 81.4% lower than in control animals. Endothelial NOS mRNA was also detected at a very low rate in the kidney of treated rats compared with control rats (22/80 vs 74/80 glomeruli, respectively). 3. These results suggest that eNOS protein and mRNA expression in glomeruli was reduced by DOCA-salt loading. Chronic volume loading may damage the glomerulus and this may be mediated, at least in part, by disruption of eNOS.

Animals↗