Biomedical subjects

T Endo

Publications and source records attributed to T Endo.

At least 109 records · Page 6Linked to original sources

PubMed2001

Cytochrome b(6)f mutation specifically affects thermal dissipation of absorbed light energy in Arabidopsis.

Light-induced lumenal acidification controls the efficiency of light harvesting by inducing thermal dissipation of excess absorbed light energy in photosystem II. We isolated an Arabidopsis mutant, pgr1 (proton gradient regulation), entirely lacking thermal dissipation, which was observed as little non-photochemical quenching of chlorophyll fluorescence. Map-based cloning showed that pgr1 had a point mutation in petC encoding the Rieske subunit of the cytochrome b(6)f complex. Although the electron transport rate was not affected at low light intensity, it was significantly restricted at high light intensity in pgr1, indicating that the lumenal acidification was not sufficient to induce thermal dissipation. This view was supported by (i) slow de-epoxidation of violaXanthin, which is closely related to lumenal acidification, and (ii) reduced 9-aminoacridine fluorescence quenching. Although lumenal acidification was insufficient to induce thermal dissipation, growth rate was not affected under low light growth conditions in pgr1. These results suggest that thermal dissipation is precisely regulated by lumenal pH to maintain maximum photosynthetic activity. We showed that pgr1 was sensitive to changes in light conditions, demonstrating that maximum activity of the cytochrome b(6)f complex is indispensable for short-term acclimation.

Arabidopsis↗

PubMed2001

Effects of light and sleep stages on heart rate variability in humans.

Effects of light intensity and sleep stages on heart rate variability (HRV) were investigated in young healthy subjects. The low-frequency (LF)/high-frequency (HF) ratio was significantly increased by exposing either to bright lights of 10 000 lx or to extreme darkness (< 0.01 lx), while HF and LF components of HRV were not changed, when compared with those under dim light (100 lx). However, LF was significantly increased at REM sleep, when compared with that at the pre-sleep wake. In contrast, HF was increased at all stages of sleep, and the LF/HF ratio was decreased at slow wave sleep during the baseline night.

Adult↗

PubMed2001

A survey on the drug therapy for delirium.

Delirium, which is experienced by 10-30% of inpatients, is commonly seen in daily practice. A survey was conducted of the delirium medications, and results were obtained from 28 psychiatric departments and related facilities. Haloperidol was used in 67% cases for the treatment of delirium. Ninety-seven per cent of facilities considered haloperidol as the drug of first choice, while 57% thought this drug had few side-effects and was easy to use. However, because the use of this drug is not covered by health insurance in Japan, its use is limited. We expect that this study on medication for the treatment of delirium will be a first step in increasing the approved indications for drugs used for the treatment of delirium, and to reduce off-label use.

Antipsychotic Agents↗

PubMed2001

Oral-cavity hair growth after free-flap transfer: case report.

It sometimes happens that hair will grow well after a free-flap transfer. But this is a report of an experience of excessive hair growth after reconstruction of a middle pharyngeal defect, using a free, vascularized, radial, forearm flap. This is a relatively rare occurrence.

Adult↗

PubMed2001

Early peak creatine kinase activity is not always a marker of successful reperfusion with myocardial salvage in patients with reperfused anterior acute myocardial infarction.

BACKGROUND: Although early peak creatine kinase activity (peak CK) is considered a reliable marker of coronary reperfusion in patients with acute myocardial infarction (AMI), whether early peak CK indicates good myocardial salvage is unclear. Moreover, some patients have late peak CK despite successful reperfusion, and its clinical implication remains to be elucidated. METHODS AND RESULTS: We examined the association of the time to peak CK with predischarge left ventricular function in 124 patients with a first AMI who had successful reperfusion within 6 hours from symptom onset. Patients were classified according to the time from reperfusion to peak CK: group A, 61 patients with peak CK < 6 hours; group B, 42 with peak CK from 6 to 12 hours; and group C, 21 with peak CK > 12 hours. There were no differences among the 3 groups in age, sex, method of reperfusion, time from symptom onset to reperfusion, collateral circulation, or the extent of risk area estimated by number of leads with ST-segment elevation. Left ventricular ejection fraction measured by predischarge left ventriculography was lowest in group A, followed by group B, and highest in group C (median values, 43%, 52%, and 60%, P < .01). Left ventricular dysfunction (left ventricular ejection fraction < or = 40%) occurred in 26 (43%) patients in group A, 8 (19%) in group B, and none in group C (P < .01). CONCLUSIONS: We conclude that compared with early peak CK, late peak CK consistently reflects good myocardial salvage in patients with anterior AMI who had successful reperfusion within 6 hours from symptom onset.

Adult↗

PubMed2001

ST-segment depression in lead aVR predicts predischarge left ventricular dysfunction in patients with reperfused anterior acute myocardial infarction with anterolateral ST-segment elevation.

BACKGROUND: Patients with an anterolateral acute myocardial infarction (AMI) have a worse prognosis, and those with additional inferolateral wall involvement might be higher risk because of more extensive area at risk. Lead -aVR obtained by inversion of images in lead aVR has been reported to provide useful information for inferolateral lesion. METHODS: We examined the relation between ST-segment deviation in lead aVR on admission electrocardiogram (ECG) and left ventricular function in 105 patients with an anterolateral AMI undergoing successful reperfusion < or = 6 hours after onset. Patients were classified according to ST-segment deviation in lead aVR on admission ECG: group A, 23 patients with ST elevation of > or = 0.5 mm; group B, 47 patients without ST deviation; and group C, 35 patients with ST depression of > or = 0.5 mm. RESULTS: There were no differences among the 3 groups in age, sex, or site of the culprit lesion. In groups A, B, and C, the peak creatine kinase level was 3661 +/- 1428, 4440 +/- 1889, and 6959 +/- 2712 mU/mL, and the left ventricular ejection fraction (LVEF) measured by predischarge left ventriculography was 54% +/- 9%, 48% +/- 7%, and 37% +/- 9%, respectively(P < .01). During hospitalization, congestive heart failure occurred more frequently in group C than in groups A or B (P < .05). ST-segment depression in lead aVR had a higher predictive accuracy than other ECG findings in identifying patients with predischarge LVEF < or = 35%. CONCLUSIONS: We conclude that in patients with an anterolateral AMI, ST-segment depression in lead aVR on admission ECG is useful for predicting larger infarct and left ventricular dysfunction despite successful reperfusion.

Adult↗

PubMed2001

A new beta-1,2-N-acetylglucosaminyltransferase that may play a role in the biosynthesis of mammalian O-mannosyl glycans.

Recent studies have shown that O-mannosyl glycans are present in several mammalian glycoproteins. Although knowledge on the functional roles of these glycans is accumulating, their biosynthetic pathways are poorly understood. Here we report the identification and initial characterization of a novel enzyme capable of forming GlcNAc beta 1-2Man linkage, namely UDP-N-acetylglucosamine: O-linked mannose beta-1,2-N-acetylglucosaminyltransferase in the microsome fraction of newborn rat brains. The enzyme transfers GlcNAc to beta-linked mannose residues, and the formed linkage was confirmed to be beta 1-2 on the basis of diplococcal beta-N-acetylhexosaminidase susceptibility and by high-pH anion-exchange chromatography. Its activity is linearly dependent on time, protein concentration, and substrate concentration and is enhanced in the presence of manganese ion. Its activity is not due to UDP-N-acetylglucosamine: alpha-3-D-mannoside beta-1,2-N-acetylglucosaminyltransferase I (GnT-I) or UDP-N-acetylglucosamine: alpha-6-D-mannoside beta-1,2-D-acetylglucosaminyltransferase II (GnT-II), which acts on the early steps of N-glycan biosynthesis, because GnT-I or GnT-II expressed in yeast cells did not show any GlcNAc transfer activity against a synthetic mannosyl peptide. Taken together, the results suggest that the GlcNAc transferase activity described here is relevant to the O-mannosyl glycan pathway in mammals.

Animals↗

PubMed2001

Control of tRNA function by antisense PNA derivatives.

The interaction of antisense peptide nucleic acid (PNA) with yeast tRNA(Phe) was investigated. A 6-mer PNA complementary to the 3'-terminal sequence including the 73ACCA end hybridized to the tRNA. While the PNA with a single mismatch did not. PNA is a promising candidate for controlling tRNA functions by the sequence-specific hybridization.

Amino Acyl-tRNA Synthetases↗

PubMed2001

Improved salt tolerance of transgenic tobacco expressing apoplastic yeast-derived invertase.

We investigated the salt tolerance of transgenic tobacco, in which yeast invertase is expressed in the apoplastic (Apo-Inv) spaces. Whereas photosynthetic activities in wild-type tobacco in light were inhibited under salt stress, transgenic Apo-Inv tobacco maintained constant photosynthetic activities. The physical appearance of plants under salt stress also indicates that yeast invertase expression in the apoplastic space is beneficial for inducing salt tolerance. Apo-Inv tobacco had a much higher osmotic pressure increase in the cell sap than did wild-type tobacco under this type of stress. The physiological importance of sucrose metabolism under salt stress is discussed.

Chloroplasts↗

PubMed2001

Lysyl oxidase and MMP-2 expression in dehydroepiandrosterone-induced polycystic ovary in rats.

Polycystic ovary syndrome (PCOS) is characterized by cystogenesis; however, the cause of this cystogenesis is unknown. At ovulation, preovulatory collagenolytic activities in the ovarian follicles increase and various proteinases are needed to degrade the tissues surrounding the follicles. To clarify the roles of enzymes in collagen degradation of the follicular wall of polycystic ovary (PCO) in relation to the cystogenesis, we examined expression of lysyl oxidase (LOX), which initiates cross-link formation of the collagen and elastin in the extracellular matrix, and expression of matrix metalloproteinases (MMPs) in ovaries of model rats with PCO induced by dehydroepiandrosterone (DHEA) compared with MMP expression in control rats. DHEA treatment increased LOX mRNA expression to more than three times the control value (P: < 0.01). MMP-2 mRNA expression in control rats was threefold greater than that in the DHEA-induced group (P: < 0.05). Expression of both latent and active forms of MMP-2 in controls was more than twice that in the DHEA-induced group (P: < 0.05) as shown by Western blotting, and expression of the active form of MMP-2 was also twice as high in the controls as in the DHEA-treated group (P: < 0.05) as shown by zymography. Our results suggest that depression of MMP-2 activity and increased LOX expression may be one of the causes of the cystogenesis of PCO.

Androstenedione↗

PubMed2001

Sudden death caused by tension pneumothorax after rupture of a thoracic aortic aneurysm. Case report.

A rare case of fatal tension pneumothorax is reported. An aged Japanese man with marked subcutaneous emphysema of the neck was found collapsed in a betting office. He was ascertained to have left tension pneumothorax, based on radiographic examinations carried out before his death. At autopsy, severe pneumomediastinum was observed, and the descending thoracic aorta with a ruptured dissecting aneurysm was closely adhered to the left lung pleura. The hemorrhage spread into the pulmonary parenchyma and finally spouted out from the surface of the lung apex. Because the blood loss itself was not fatal in quantity, it is concluded that the patient died of tension pneumothorax caused by a lung penetration from the rupture of an aortic aneurysm.

Aged↗

PubMed2001

Acute hypotension and bradycardia by medulla oblongata compression in spinal surgery.

A 71-year-old man was admitted to the hospital with subarachnoid hemorrhage caused by a cervical dural arteriovenous shunt. During surgery, the patient developed acute hypotension and bradycardia, probably caused by surgical compression of the medulla oblongata. During posterior fossa and upper cervical surgery, monitoring cardiovascular, respiratory, and evoked potential parameters is advocated. In the current case, only cardiovascular monitoring detected alteration of brain stem function. Anesthesiologists should be aware that surgical manipulation of the dorsal medulla might cause hemodynamic changes and expose patients to danger. Through close cardiovascular monitoring we can rapidly detect changes in vital signs, which allows prompt intervention to prevent irreversible neurologic deficits and potentially catastrophic patient outcome.

Aged↗

PubMed2001

Protein-protein interaction panel using mouse full-length cDNAs.

We have developed a novel assay system for systematic analysis of protein-protein interactions (PPIs) that is characteristic of a PCR-mediated rapid sample preparation and a high-throughput assay system based on the mammalian two-hybrid method. Using gene-specific primers, we successfully constructed the assay samples by two rounds of PCR with up to 3.6 kb from the first-round PCR fragments. In the assay system, we designed all the steps to be performed by adding only samples, reagents, and cells into 384-well assay plates using two types of semiautomatic multiple dispensers. The system enabled us examine more than 20,000 assay wells per day. We detected 145 interactions in our pilot study using 3500 samples derived from mouse full-length enriched cDNAs. Analysis of the interaction data showed both several significant interaction clusters and predicted functions of a few uncharacterized proteins. In combination with our comprehensive mouse full-length cDNA clone bank covering a large part of the whole genes, our high-throughput assay system will discover many interactions to facilitate understanding of the function of uncharacterized proteins and the molecular mechanism of crucial biological processes, and also enable completion of a rough draft of the entire PPI panel in certain cell types or tissues of mouse within a short time.

Animals↗

PubMed2001

Development of an automated method for detecting mammographic masses with a partial loss of region.

Recently, we have been developing several automated algorithms for detecting masses on mammograms. For our algorithm, we devised an adaptive thresholding technique for detecting masses, but our system failed to detect masses with a partial loss of region that were located on the edge of the film. This is a common issue in all of the algorithms developed so far by other groups. In order to deal with this problem, we propose a new method in the present study. The partial loss masses are identified by their similarity to a sector-form model in the template matching process. To calculate the similarity, four features are applied: 1) average pixel value; 2) standard deviation of pixel values; 3) standard correlation coefficient defined by the sector-form model; and 4) concentration feature determined from the density gradient. After employing the new method to 335 digitized mammograms, the detection sensitivity for the partial loss masses jumped from 70% to 90% when the number of false positives was kept constant (0.2/image). Moreover, a combination of the existing method and the new method improved the true-positive rate up to 97%. Such results indicate that the new technique may improve the performance of our computer-aided diagnosis system for mammographic masses effectively.

Algorithms↗

PubMed2001

[Isolation and incidence of Cryptosporidium and Giardia from river water].

A study was conducted during the period from July to October in 1999, surface water samples were collected from 13 rivers in Hyogo Prefecture serving as tap water sources and examined for Cryptosporidium oocysts and Giardia cysts using the immunomagnetic separation method. In 9 (69%) of the 13 rivers, Cryptosporidium oocyst was detected. Giardia cyst was detected in 5 (38%) of the 13 rivers. The Cryptosporidium oocyst positive rate was comparable to that of fecal bacteriological indicators, which was also examined and detected in 10 (77%) of 13 rivers. Water samples were collected at 69 points in the 13 rivers. Cryptosporidium parvum oocyst was detected at 38 (55%) of the 69 points, demonstrating widely spread contamination. Comparing 3 areas which were divided on the basis of agricultural circumstance as well as geographical locating, the Cryptosporidium positive rate varied widely according to the area, ranging from 37% to 100%. To elucidate the reason for these differences, the relationship between positive rate and the species and number of livestock animals raised in each respective region was investigated. The results showed a strong correlation (r = 0.91) between the number of raised cattle and contamination with the rate of Cryptosporidium in each area. Furthermore, genetic analysis by PCR-restriction fragment length polymophism method revealed that C. parvum oocyst detected in the rivers studied was the bovine type, probably indicating that the oocyst was excreted from the cattle in the river basins. The degree of contamination with Cryptosporidium in river water was comparable to that of fecal bacteriological indicators, suggesting the possibility that fecal bacteriological indicators examination might be used as a criterion of Cryptosporidium contamination.

Animals↗

PubMed2001

[Investigation of infective endocarditis clinical isolates of methicillin resistant Staphylococcus aureus non-responsive to vancomycin].

Methicillin resistant Staphylococcus aureus (MRSA) is one of the most important strains which induce hospital and post-operative infection. In cases of infective endocarditis in which VCM was not efficacious, MRSA strains were chronologically isolated at three different times and examined with the following parameters: minimum inhibitory concentration (MIC), fractional inhibitory concentration (FIC) index, Mu 3 agar, population analysis, pulse field gel electropholesis (PFGE). The PFGE banding patterns of the three MRSA isolates were the same, therefore, it was concluded that the same strain of MRSA was selected for reduced susceptibility. A pattern of Mu 3 and Mu 50 was demonstrated under population analysis.

Endocarditis, Bacterial↗

PubMed2001

Contamination of river water by Cryptosporidium parvum oocysts in western Japan.

In Japan, only a few rivers have been inspected for Cryptosporidium parvum contamination, and the methods used had low sensitivity. In 1998 and 1999, we used a method with higher sensitivity to examine all large rivers used as sources of water supply in one prefecture (which we divided into four areas) in western Japan for Cryptosporidium oocysts. One sample was collected at each of 156 sites along 18 rivers, and samples were tested for Cryptosporidium oocysts by immunomagnetic separation. Samples were classified as being obtained on an island with livestock and fishing industries, a densely populated urban area, a western region including farming villages, or a still more rural northern area with agriculture and fishing. Restriction fragment length polymorphism analysis was used for identification of the C. parvum found as the bovine or human type. C. parvum was detected in at least one sample from 13 of the 18 rivers and in 47% (74 of 156) of the samples. One-third to all of the samples from each area contained C. parvum oocysts. The number of C. parvum oocysts per 20 liters of river water varied in the same pattern as the number of cattle kept in the four kinds of areas (as determined by the Mantel extension test). Oocysts isolated were of the bovine type; the C. parvum detected in rivers probably came from cattle kept in that valley. As we had expected, when tested with a more sensitive method, river water in western Japan was found to be greatly contaminated with C. parvum oocysts, as reported in other countries.

Animals↗

PubMed2001

Detection of hypermethylation of the p16(INK4A) gene promoter in chronic hepatitis and cirrhosis associated with hepatitis B or C virus.

BACKGROUND/AIM: Inactivation of the p16(INK4A) (p16) tumour suppressor gene by promoter region hypermethylation has been demonstrated not only in many types of tumours, including hepatocellular carcinoma (HCC), but also in early preneoplastic lesions in the lung, colon, oesophagus, and pancreas. The aim of this study was to examine the methylation status of the p16 promoter in pre- and/or non-neoplastic liver diseases. PATIENTS/SUBJECTS/METHODS: The methylation status of p16 was evaluated in 22 HCC, 17 cirrhosis, 17 chronic hepatitis, nine primary biliary cirrhosis (PBC), eight autoimmune hepatitis, seven drug induced liver disease, six fatty liver, and three normal liver tissues using methylation specific polymerase chain reaction (MSP). p16 protein expression was also examined by immunohistochemical staining. RESULTS: Methylation of the p16 promoter was detected in HCC (72.7%, 16/22) and also in cirrhosis (29.4%, 5/17) and chronic hepatitis (23.5%, 4/17), all of which were positive for hepatitis B or C virus infections. Methylation was not detected in any of the other samples. All methylation positive HCC, cirrhosis, and chronic hepatitis samples showed loss of p16 expression, and a significant correlation was found between methylation and loss of expression. Analysis of serial samples from individual patients with methylation positive HCC revealed that loss of p16 expression with promoter methylation occurred in 18 of 20 patients at the stage of chronic hepatitis without clinically detectable carcinoma. CONCLUSIONS: Our results suggest that methylation of the p16 promoter and the resulting loss of p16 protein expression are early events in a subset of hepatocarcinogenesis and that their detection is useful in the follow up of patients with a high risk of developing HCC, such as those with hepatitis B or C viral infections.

Adult↗