Search PubMed⌕ Search

Biomedical subjects

K Uemura

Publications and source records attributed to K Uemura.

At least 19 recordsLinked to original sources
PubMed2006

Inclusion of an S-nitrosylating agent in the insufflating gas does not alter gastric activity in rats following pneumoperitoneum.

BACKGROUND: We have previously shown that mixing the S-nitrosylating agent ethyl nitrite with carbon dioxide can attenuate pneumoperitoneum-induced decreases in splanchnic blood flow, but it was unclear if this agent would alter gastric function. This question was answered using rats by assessing gastric emptying and gastrointestinal transit times following gavage with radioactive chromium. METHODS: There were five experimental groups: absolute control, anesthesia control, and carbon dioxide alone or with 100 or 300 parts per million ethyl nitrite. The period of insufflation was 1 h, and all animals were euthanized 6.5 h after chromium administration. RESULTS: The mean amount of radioactivity remaining in the stomach ranged between 16% and 27% of the total administered; these differences were not statistically significant (p > 0.05). Modest differences in chromium distribution were identified in the gastrointestinal tract, but for all treatments, the peak amount of radioactivity was located in the distal portion. Location of the peak, expressed as a percentage of total tract length, varied between 70% and 85% (p = 0.366). CONCLUSIONS: This study found no adverse effect of ethyl nitrite on postoperative gastric emptying or gastrointestinal transit time following pneumoperitoneum. The findings support continued assessment of the clinical utility of ethyl nitrite in the setting of laparoscopic surgery.

Animals↗
PubMed2004

Magnitude of abdominal incision affects the duration of postoperative ileus in rats.

BACKGROUND: The pathogenesis of reduced postoperative ileus (POI) in laparoscopic gastrointestinal (GI) surgery still remains controversial. The aim of this study was to investigate the effect of surgical incision on postoperative ileus. METHODS: The effects of length, depth, and site of the incision on GI transit were compared using the geometric center of 51Cr in rats. The inhibitory mechanism of abdominal incision on GI transit also was studied. RESULTS: The findings showed that 5 cm of abdominal skin and the 5-cm back muscle incision had no significant effect on GI transit. However, the 5-cm abdominal muscle-fascia incision and a 5-cm laparotomy significantly delayed GI transit. Gastrointestinal transit after a 5-cm laparotomy was significantly delayed, as compared with that of a 1-cm laparotomy regardless whether intestinal manipulation was performed or not. Guanethidine and yohimbine, but not propranolol, significantly improved the impaired GI transit after a 5-cm laparotomy. CONCLUSIONS: The results suggest that the longer and deeper abdominal incision more profoundly inhibits GI transit. The inhibitory effect of abdominal incision is mediated via the activation of the somatosympathetic reflex and alpha-2 adrenoceptors.

Abdominal Injuries↗
PubMed2004

Sudden death of a patient with primary hypereosinophilia, colon tumours, and pulmonary emboli.

A 33 year old man was admitted to hospital six days after the onset of abdominal pain. There was hypereosinophilia, but the cause could not be identified (primary hypereosinophilia). The hypereosinophilia, high C reactive protein concentration, and gastrointestinal symptoms were alleviated by corticosteroid treatment. Unexpectedly, after this apparent recovery, he was found dead on the 27th day after admission. Necropsy disclosed two solid tumours primarily composed of eosinophils in the ascending and transverse colon. The cause of the sudden death was pulmonary artery emboli, derived from a thrombus in the left iliac vein.

Adult↗
PubMed2003

Perfusion-weighted MRI of spinal dural arteriovenous fistula.

A 72-year-old woman was admitted with rapidly progressive paraplegia and sphincter disturbance. T2-weighted images of the thoracic spine showed intramedullary high signal with flow voids suggesting dilated medullary veins. Conventional spinal angiography demonstrated a dural arteriovenous fistula draining into perimedullary veins. Perfusion-weighted MRI demonstrated a prolonged mean transit time and increased blood volume in the high-signal area. The loss of normal perfusion gradient and venous hypertension and were thought to produce these differences. The time-to-peak was almost identical in the high-signal and isointense areas, although the bolus of contrast medium arrived earlier in the former. Arteriovenous shunting was thought to cause faster inflow. These changes may have resulted in increased blood volume in the spinal cord. The high signal has been attributed to oedema due to venous congestion, but there has been no histological confirmation. Perfusion MRI in this case supports this hypothesis.

Aged↗
PubMed2003

Physicians's reports on the impact of living wills at the end of life in Japan.

CONTEXT: A growing number of Japanese people have completed advance directives, especially living wills, even though there is no legislation recognising such documents and little empirical research on their impact on clinical care at the end of life in Japan. OBJECTIVES: To investigate physicians' attitudes about living wills and their experiences with patients who had completed a living will and later died. DESIGN: Self administered survey and qualitative study using open question and content analysis. SETTING: Japan. PARTICIPANTS: Physicians known to have cared for a patient who had presented a living will prior to death. MEASUREMENTS: The physician's response to receiving a living will, communication about the living will, the impact of the living will on clinical care, demographics, and their opinion on advance directives, especially living wills. MAIN RESULTS: Fifty five per cent of respondents approved of advance directives in general, and 34% had more opportunities to communicate with a patient and his/her family after receiving the living will. Sixty nine per cent of the physicians who received a living will did not, however, change their course of therapy as a consequence of receiving the living wills. Based on the analysis, we identified three areas of concern in the comments on living wills: (1) concerns relative to patients, physicians, and families; (2) social context, and (3) clinical and administrative concerns. The physicians raised various topics for discussion; they tended to describe the issues from a clinical perspective. CONCLUSIONS: Our identified areas of concern should prove helpful in better understanding the clinical and ethical implications of living wills in Japan.

Advance Directive Adherence↗
PubMed2001

Lipid peroxidation in the rat brain after CO inhalation is temperature dependent.

We reported previously that 7-hydroperoxycholesterols, 7 alpha- and 7 beta-hydroperoxycholest-5-en-3 beta-ol (7 alpha-OOH and 7 beta-OOH), indicated lipid peroxidation. In the present study, we measured not only 7-hydroperoxycholesterols but also oxysterols (7 alpha- and 7 beta-hydroxycholesterol, 7 alpha-OH, and 7 beta-OH) and 3 beta-hydroxycholest-5-en-7-one (7-keto) in the brains of rats that underwent either a sham operation (control), hypoxia, or CO inhalation (1005 ppm) at 37 degrees C for 90 min followed by 48 h of recovery. The levels of 7-hydroperoxycholesterols, 7 beta-OH, and 7-keto were low in the hypoxia group, while the levels were unaltered in the CO group compared with the controls. Among the three groups of CO inhalation, these levels were high in the hyperthermia group (39 degrees C), and the 7-hydroperoxycholesterols were low in the hypothermia group (32 degrees C), compared with the control group. The blood O(2) saturation was almost normal in the hypothermia group, while it was similarly low in the hyperthermia and normothermia groups. The temperature-dependent lipid peroxidation in the brain after CO inhalation and recovery can not be explained by hypoxia due to CO-hemoglobin formation, but may contribute to the delayed neuronal death following CO inhalation. Hypothermia may be applicable to treat patients after CO inhalation.

Administration, Inhalation↗
PubMed2001

Phosphoinositide 3-kinase accelerates necrotic cell death during hypoxia.

Using H9c2 cells derived from rat cardiomyocytes, we investigated the mechanism of cell death during hypoxia in the presence of serum and glucose. Hypoxic cell death is by necrosis and is accompanied by metabolic acidosis. Moreover, hypoxic cell death is inhibited by Hepes buffer as well as by 2-deoxyglucose, an inhibitor of glycolysis, indicating that metabolic acidosis should play an essential role in hypoxic injury. The involvement of phosphoinositide 3-kinase (PI 3-kinase), which is known to activate glucose metabolism, was examined using its inhibitor, LY290042, or adenovirus-mediated gene transfer. Hypoxic cell death was inhibited by LY294002 in a dose-dependent manner. Overexpression of dominant negative PI 3-kinase was found to reduce cell death, whereas wild-type PI 3-kinase enhanced it. Dominant negative PI 3-kinase also reduced glucose consumption and acidosis, but this was stimulated by wild-type PI 3-kinase. The data indicate that PI 3-kinase stimulates cell death by enhancing metabolic acidosis. LY294002 significantly reduced glucose uptake, showing that PI 3-kinase regulates glycolysis at the step of glucose transport. These findings indicate the pivotal role of glucose metabolism in hypoxic cell death, and reveal a novel death-promoting effect of PI 3-kinase during hypoxia, despite this enzyme being considered to be a survival-promoting factor.

Acidosis↗
PubMed2001

Apoptotic and necrotic brain lesions in a fatal case of carbon monoxide poisoning.

A 41-year-old man was accidentally exposed to carbon monoxide (CO) gas and found in a state of cardiopulmonary arrest while he took bath. After admission, he was resuscitated and underwent artificial ventilation in a comatose state and died about 19h later. Computed tomography (CT) examination disclosed bilateral low density area in the basal ganglia and the thalamus, a well-known finding in the CO intoxication. Necropsy, histological examination, DNA ladder assay gave the first line of evidence for the presence of apoptosis as well as necrosis in the human case of CO intoxication. TdT-mediated dUTP-biotin nick-end labeling (TUNEL) positive apoptotic cells were more predominant in the CA2 area than in CA1 area. There is general co-relation between the ratio of TUNEL-positive cells and the DNA laddering on the agarose gel. Basal ganglia and thalamus, which showed bilateral low density area in CT, were revealed to be severe edema. The two types of cell death occurred in the cortex, basal ganglia, hippocampus, thalamus, and cerebellum. Hypoxia caused by CO-hemoglobin formation alone cannot explain the phenomena.

Adult↗
PubMed2001

Tail-vein injection of mannan-binding lectin DNA leads to high expression levels of multimeric protein in liver.

The human plasma protein mannan-binding lectin (MBL) is an essential part of the innate immune defense system. Low levels of MBL are associated with recurrent infections and other clinically significant signs of a compromised immune defense. Previous studies have addressed the possibility of reconstitution therapy by the use of recombinant or plasma-derived protein. Natural MBL is a multimeric protein, which consists of up to 18 identical polypeptide chains. Synthesis by in vitro methods of MBL with the proper multimeric structure is difficult. We here report that mice obtain MBL levels comparable to those found in normal human plasma when injected with an MBL expression construct as naked plasmid DNA contained in a large volume of physiologic salt solution. The expression was confined to the liver and high MBL expression levels were obtained with less than 5% of the liver cells transfected. The multimeric structure of the MBL found in plasma of injected mice was similar to that of natural MBL. Thus, liver expression following injection of naked DNA is an alternative to reconstitution therapy with a protein having a complex quaternary structure.

Animals↗
PubMed2001

Comparison of parametric FBP and OS-EM reconstruction algorithm images for PET dynamic study.

An ordered subsets expectation maximization (OS-EM) algorithm is used for image reconstruction to suppress image noise and to make non-negative value images. We have applied OS-EM to a digital brain phantom and to human brain 18F-FDG PET kinetic studies to generate parametric images. A 45 min dynamic scan was performed starting injection of FDG with a 2D PET scanner. The images were reconstructed with OS-EM (6 iterations, 16 subsets) and with filtered backprojection (FBP), and K1, k2 and k3 images were created by the Marquardt non-linear least squares method based on the 3-parameter kinetic model. Although the OS-EM activity images correlated fairly well with those obtained by FBP, the pixel correlations were poor for the k2 and k3 parametric images, but the plots were scattered along the line of identity and the mean values for K1, k2 and k3 obtained by OS-EM were almost equal to those by FBP. The kinetic fitting error for OS-EM was no smaller than that for FBP. The results suggest that OS-EM is not necessarily superior to FBP for creating parametric images.

Algorithms↗
PubMed2001

The effect of public long-term care insurance plan on care management and care planning in Japanese geriatric hospitals.

Japan, a society facing demographic aging at an incomparable speed, decided to introduce a new public long-term care insurance system to meet the expected need for elders to be cared for in the near future. The purpose of this study was to examine the change in knowledgeability on the side of managers of Japanese geriatric hospitals regarding (1) the concept of care-management as the methodology to supply care services to the elderly smoothly, and (2) comprehensive assessment for the elders as the technical skill in the process of materializing care management. Subjects were interviewed and questioned over the telephone according to a structural questionnaire. Managers (directors and office managers) of geriatric hospitals in 1996 and 1999. In 1996, the rate of knowledgeability for care management on the side of managers of geriatric hospitals was 70.0% (28/40) as a whole, increasing to 97.3% (71/73) in 1999. With regard to MDS-RAPs, the knowledgeability rate increased from 57.5% (23/40) in 1996 to 95.9% (70/73) in 1999. However, regarding care planning, almost all of the hospitals that performed care planning were those in the category required to submit care plans to the municipal government. Geriatric hospitals that were not required to submit such plans did not perform such planning either in 1996 or in 1999. It can be concluded that the decision to introduce a long-term care insurance system in Japan has led to a deeper understanding of the methodology of care management and a comprehensive assessment on the side of managers of geriatric hospitals.

Journal Article↗
PubMed2001

Expression of JNK cascade scaffold protein JSAP1 in the mouse nervous system.

The mitogen-activated protein kinase (MAPK) cascades consist of MAPK, MAPK kinase (MAPKK), and MAPKK kinase (MAPKKK). The specificity of activation of MAPK cascades may be determined, in part, by scaffold proteins that organize multi-enzyme complexes. We have earlier reported a scaffold protein JSAP1 (also known as JIP3) in the JNK MAPK cascade. We also showed that, of the adult mouse tissues tested, JSAP1 mRNA was predominantly expressed in brain. Here we report the localization of JSAP1 protein in mouse embryos and adult brain by immunohistochemical analysis. In embryos (E11-16), JSAP1 immunoreactivity was mainly found in the central and peripheral nervous systems, where it was localized to the cell bodies and/or axons of developing neurons, but not neural precursor cells. In the adult brain, immunoreactive JSAP1 was localized mostly to cell bodies in almost all neurons. We also showed that the expression of JSAP1 transcripts and proteins gradually increased during the neural differentiation of mouse P19 embryonal carcinoma (EC) cells. Furthermore, we showed that overexpressed JSAP1 facilitated the efficient activation of JNK by MEKK1 in P19 cells. These results suggest that JSAP1 may function as a scaffold protein for the JNK signaling module in neuronal cells.

Adaptor Proteins, Signal Transducing↗
PubMed2001

Architecture of baked breads depicted by a magnetic resonance imaging.

The architecture of baked breads made of fresh dough and frozen dough was depicted by magnetic resonance imaging (MRI). Pieces of bread (16 mm cubic cakes) were soaked in organic solvents containing various concentrations of heavy metals (Cu(2+), Co(2+) and Fe(3+)) and images of the grain structure of the breads were obtained. Of the organic solvents tested, acetone was preferable because of its single peak that prevents chemical shift effects on images, the retention of the bread structure, and the solubility of heavy metals. The heavy metals, especially Fe(3+), shortened the overly long relaxation times of acetone to practical lengths for imaging and stained the materials to provide high contrasts. The images obtained in acetone with 8 mM Fe(3+) were suitable for analyzing crumb grain structures. The bread of fresh dough showed a uniform distribution of pores of various sizes made of thin gluten sheets, whereas the pores in the bread of frozen dough were less, prominently large, non-uniformly distributed, and made of thick gluten sheets.

Bread↗
PubMed2001

Recombinant expression of human mannan-binding lectin.

Mannan-binding lectin (MBL) constitutes an important part of the innate immune defence by effecting the deposition of complement on microbial surfaces. MBL deficiency is among the most common primary immunodeficiencies and is associated with recurrent infections and symptoms of poor immune complex clearance. Plasma-derived MBL has been used in reconstitution therapy but concerns over viral contamination and production capacity point to recombinant MBL (rMBL) as a future source of this protein for clinical use. Natural human MBL is an oligomer of up to 18 identical polypeptide chains. The synthesis of rMBL has been accomplished in several mammalian cell lines, however, the recombinant protein differed structurally from natural MBL. In this, study we compare rMBL produced in myeloma cells, Chinese hamster ovary (CHO) cells, human hepatocytes, and human embryonic kidney (HEK) cells. We report that rMBL structurally and functionally similar to natural MBL can be obtained through synthesis in the human embryonic kidney cells followed by selective carbohydrate affinity chromatography.

Carrier Proteins↗
PubMed2001

In vivo assessment of acetylcholine-releasing function at cardiac vagal nerve terminals.

We examined whether the ACh concentration measured by cardiac microdialysis provided information on left ventricular ACh levels under a variety of vagal stimulatory and modulatory conditions in anesthetized cats. Local administration of KCl (n = 5) and ouabain (n = 7) significantly increased the ACh concentration in the dialysate to 4.3 +/- 0.8 and 7.3 +/- 1.3 nmol/l, respectively, from the baseline value of 0.6 +/- 0.5 nmol/l. Intravenous administration of phenylbiguanide (n = 5) and phenylephrine (n = 6) significantly increased the ACh concentration to 5.4 +/- 0.9 and 6.0 +/- 1.5 nmol/l, respectively, suggesting that the Bezold-Jarisch and arterial baroreceptor reflexes affected myocardial ACh levels. Modulation of vagal nerve terminal function by local administration of tetrodotoxin (n = 6), hemicholinium-3 (n = 6), and vesamicol (n = 5) significantly suppressed the electrical stimulation-induced ACh release from 20.4 +/- 3.9 to 0.6 +/- 0.1, 7.2 +/- 1.9, and 2.7 +/- 0.6 nmol/l, respectively. Increasing the heart rate from 120 to 200 beats/min significantly reduced the myocardial ACh levels during electrical vagal stimulation, suggesting a heart rate-dependent washout of ACh. We conclude that ACh concentration measured by cardiac microdialysis provides information regarding ACh release and disposition under a variety of pathophysiological conditions in vivo.

Acetylcholine↗
PubMed2001

Intraosseous meningioma of the posterior fossa--Case report.

A 62-year-old male presented with a rare intraosseous meningioma with intradural extension manifesting as frequent vomiting and floating sensation that had persisted for 3 months. Neuroimaging detected a mass lesion that was mainly located extradurally in the right posterior fossa with a daughter lesion inside the dura. He underwent surgical excision of the mass lesion. Craniectomy exposed the main lesion of the tumor just beneath the thinned outer table of the skull, and in the extradural space, with the daughter lesion penetrating the dura. Both portions of the tumor were resected. There was no attachment to the adjacent dura mater. Histological examination showed meningotheliomatous meningioma containing scattered bony tissue. This intraosseous meningioma probably originated from the occipital bone with a small intradural extension caused by mechanical compression.

Cerebral Angiography↗
PubMed2001

Sacral meningeal cyst associated with valve-like mechanism--case report.

A 58-year-old woman presented with low back pain radiating to the lower extremities. Magnetic resonance imaging revealed a cystic lesion in the sacrum compressing the nerve roots. At operation, a valve-like communication was found between the subarachnoid space and the cyst cavity in the vicinity of the sacral nerve root. The communication was obliterated with a purse-string suture and reinforced with a free muscle graft. Postoperatively, she reported improvement of the pain. Valve-like communication between the cyst cavity and subarachnoid space can cause enlargement of spinal meningeal cyst, and could also explain enlargement of sacral meningeal cyst. Surgical obliteration of the communication rather than the cyst resection is more important for sacral meningeal cyst.

Cysts↗