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H Ogino

Publications and source records attributed to H Ogino.

At least 37 records · Page 2Linked to original sources
PubMed2001

Isolation, characterization, and expression analysis of zebrafish large Mafs.

Large Maf proteins, which are members of the basic leucine zipper (b-Zip) superfamily, are involved in the determination and control of cellular differentiation. The expression patterns of various vertebrate large Maf mRNAs were described previously. Here, we report the cloning of a novel zebrafish large Maf cDNA, SMaf1 (Somite Maf1), and other zebrafish large Mafs, the N-terminus domains of which possess transactivational activity. We also analyzed the expression patterns of SMaf1 and SMaf2 (Somite Maf2)/Krml2 as well as MafB/Val and c-Maf during zebrafish embryogenesis. In particular, the robust expression of the novel SMaf1 mRNA, which overlapped that of MyoD, in somitic cells during somitogenesis was noteworthy. In addition, the expression patterns of SMaf2 and MafB in the blood-forming regions, and those of c-Maf and MafB in the lens cells showed spatial redundancy, although the temporal appearance of these genes at these sites differed. These data indicate that SMafs may play important roles in somitogenesis, and that Maf proteins may have overlapping and yet specific functions as to the determination and differentiation of cell lineages.

Amino Acid Sequence↗
PubMed2001

Malignant peripheral nerve sheath tumors of intrathoracic vagus nerve.

The authors report two cases of malignant peripheral nerve sheath tumors arising from the vagus nerve in the mediastinum in patients who had no stigmata of neurofibromatosis (von Recklinghausen's disease). Computed tomography showed homogeneous soft tissue masses, with minimal calcification seen in one patient. T2-weighted magnetic resonance images showed regions of low signal intensity caused by a dense cellular population.

Adult↗
PubMed2001

Role of intermolecular disulfide bonds of the organic solvent-stable PST-01 protease in its organic solvent stability.

The PST-01 protease is secreted by the organic solvent-tolerant microorganism Pseudomonas aeruginosa PST-01 and is stable in the presence of various organic solvents. Therefore, the PST-01 strain and the PST-01 protease are very useful for fermentation and reactions in the presence of organic solvents, respectively. The organic solvent-stable PST-01 protease has two disulfide bonds (between Cys-30 and Cys-58 and between Cys-270 and Cys-297) in its molecule. Mutant PST-01 proteases in which one or both of the disulfide bonds were deleted were constructed by site-directed mutagenesis, and the effect of the disulfide bonds on the activity and the various stabilities was investigated. The disulfide bond between Cys-270 and Cys-297 in the PST-01 protease was found to be essential for its activity. The disulfide bond between Cys-30 and Cys-58 played an important role in the organic solvent stability of the PST-01 protease.

Disulfides↗
PubMed2001

Enzymes which are stable in the presence of organic solvents.

There are numerous advantages of employing enzymes as catalysts in organic solvents or aqueous solutions containing organic solvents instead of water. A few natural enzymes which are stable in the presence of organic solvents have been discovered. However, almost all natural enzymes are easily denatured and inactivated in the presence of organic solvents. Therefore, several physical and chemical methods, such as immobilization, modification, and entrapment, for stabilizing enzymes in the presence of organic solvents were developed. Protein engineering using site directed mutagenesis and directed evolution are useful for clarifying why organic solvent-stable enzymes are stable in the presence of organic solvents and for developing organic solvent-stable mutant enzymes.

Journal Article↗
PubMed2001

Lipase production in two-step fed-batch culture of organic solvent-tolerant Pseudomonas aeruginosa LST-03.

Efficient lipase production by two-step fed-batch culture of an organic solvent-tolerant bacterium, Pseudomonas aeruginosa LST-03, was investigated. When FB synthetic medium was used in flask culture, no lipase activity was detected, whereas lipase was produced at 2.3 I.U./ml in C2 complex medium. However, lipase production was induced in FB medium when a fatty acid was added to the culture broth in the stationary phase. Among fatty acids tested, long chain saturated fatty acids, such as C18 (stearic acid) and C20 (arachidic acid), were found to function as effective inducers for the production of lipase, giving an activity level almost the same as that obtained in C2 medium in flask culture. Two-step lipase production, comprised of a growth phase in fed-batch mode and a production phase in which lipase was induced by the addition of 5% (v/v) stearic acid, was carried out in a jar-fermentor. In the growth phase, the maximum cell concentration at 16 h was only 20 in terms of the optical density at 660 nm (OD660), and a low level of lipase production (8 I.U./ml) was obtained after 167 h. This was considered to be due to the exhaustion of several medium components brought about by the use of an unsuitable medium or feeding solution. After analyzing the contents of the compounds in the culture broth by inductively coupled plasma spectrometry for metal ions and HPLC for anions, a modified FB medium was designed. When this modified FB medium was used in two-step fed-batch culture, the maximum cell concentration reached an OD660 of 55 (30.2 g-dry cells/l) at 16.5 h, and lipase was produced at 96 I.U./ml after 35 h, which is approximately 40 times higher than the production level obtained in flask culture using C2 medium.

Journal Article↗
PubMed2001

[Surgery for thoracic aortic aneurysms involving the distal arch through a left thoracotomy].

Surgical outcome for thoracic aortic aneurysms involving the distal arch via a left thoracotomy using retrograde cerebral perfusion combined with profound hypothermic circulatory arrest was reviewed. Twelve patients with a atherosclerotic aortic aneurysm between 1994 and 1997 were involved. A proximal aortic anastomosis was made by means of an open aortic technique. For the first four patients, oxygenated arterial blood from cardiopulmonary bypass was perfused retrogradely through a venous cannula positioned into the right atrium. In the last eight cases, venous blood provided by a low-flow perfusion of the lower half body via the femoral artery, which was still oxygen-saturated, was circulated passively in the brain in a retrograde fashion with the descending aorta clamped. Prosthetic replacement was done between the distal arch and the proximal descending aorta in 6 patients and from the distal arch to the entire descending thoracic aorta in 6 patients. The median duration of hypothermic circulatory arrest and continuous retrograde cerebral perfusion was 36 minutes and 33 minutes respectively. The overall outcome was satisfactory without early mortality--all patients survived, although an octogenarian died of respiratory failure 1 year postoperatively. Another octogenarian with a ruptured aneurysm developed delay of meaningful consciousness, and other two patients with a severely atherosclerotic aneurysm suffered permanent neurological dysfunction (stroke) presumably due to an embolic episode. The safe and simple combination of profound hypothermic circulatory arrest, retrograde cerebral perfusion, and open aortic anastomosis protects the brain adequately and produces satisfactory results in surgery for aortic aneurysms involving the distal arch through a left thoracotomy.

Aged↗
PubMed2001

[Mediastinal cystic lesions: CT and MRI findings].

In this article we describe various approaches to the evaluation of mediastinal cystic lesions using CT and MRI. Although cystic lesions generally appear to be uncomplicated and not difficult to diagnose, we consider that there are certain pitfalls in differentiating them from solid lesions. It is important to pay careful attention to the location (including ectopic occurrence), CT attenuation and/or MR intensity, thickness of the wall, tear-drop shape or alternation of shape owing to intrathoracic pressure, and pseudoenhancement. We suggest that MR be recommended when the findings of CT are equivocal, as they were in 32 of our cases.

Adult↗
PubMed2001

[Emergent surgical treatment of type A acute aortic dissection in an elderly patient].

An 86-year-old man with severe chest pain and shock was transferred to our hospital. Computed tomography revealed type A aortic dissection with cardiac tamponade. He needed intubation and closed chest massage preoperatively. At operation, intrapericardial space was filled with clotted blood and rupture of the ascending aorta was confirmed. He underwent a successful emergency graft replacement of the ascending aorta. Postoperative course was uneventful except for mild hemianopsia due to cerebral infarction. He had recovered to be able to walk and is doing well.

Acute Disease↗
PubMed2000

Cloning and sequencing of a gene of organic solvent-stable protease secreted from Pseudomonas aeruginosa PST-01 and its expression in Escherichia coli.

A gene of organic solvent-stable protease (PST-01 protease) secreted by Pseudomonas aeruginosa PST-01 was cloned and its nucleotide was sequenced. The nucleotide sequence analysis revealed that the PST-01 protease was a pseudolysin, which was an elastase produced by P. aeruginosa and was well characterized by the previous investigators. The PST-01 protease produced in recombinant Escherichia coli was not secreted into the extracellular medium, but its proenzyme was released by the lysis of the cells and became a 33.1kDa mature enzyme autoproteolytically. Its characteristics including organic solvent stability were as same as those of the PST-01 protease secreted by P. aeruginosa PST-01.

Journal Article↗
PubMed2000

The synthetic rate of dipeptide catalyzed by organic solvent-stable protease from Pseudomonas aeruginosa PST-01 in the presence of water-soluble organic solvents.

The initial synthetic rates of peptide Cbz-Arg-Leu-NH(2) from Cbz-Arg and Leu-NH(2) using PST-01 protease in the presence and absence of organic solvents were investigated under various conditions. The synthetic rates of Cbz-Arg-Leu-NH(2) in the presence of 50% (v/v) methanol, 50% (v/v) N,N-dimethylformamide (DMF) and 60% (v/v) dimethyl sulfoxide (DMSO) were 1.6-, 2.4-, and 5.1-times higher than that in the absence of organic solvent, respectively. The PST-01 protease was not only stable in the presence of organic solvents but also exhibited high reaction rates in the presence of methanol, DMF, and DMSO. When the Cbz-Arg concentration was lower than 60mM or the Leu-NH(2) concentration was lower than 400mM, the initial rates increased lineally with increase in their concentrations. However, the rates did not increase when the Leu-NH(2) concentration was more than 500mM. The optimum temperature and pH of the reaction were 40 degrees C and 7.0, respectively.

Journal Article↗
PubMed2000

beta-blocker therapy in patients after aortic valve replacement for aortic regurgitation.

BACKGROUND: beta-blocker therapy for dilated or ischemic cardiomyopathy is now an accepted and effective treatment. However, little is known about its efficacy in patients with postoperative impaired left ventricular function. This retrospective study was designed to assess the effects of beta-blocker therapy in patients after aortic valve replacement (AVR) for aortic regurgitation (AR). METHODS: A total of 59 patients who underwent AVR for chronic AR were assigned to four groups. Twelve patients were treated with both ACE inhibitors and beta-blockers, 12 patients with only ACE inhibitors, eight patients with only beta-blockers, and 27 patients without beta-blockers or ACE inhibitors. A postoperative echocardiographic study was performed one year after surgery. RESULTS: The heart rate was significantly reduced in patients with beta-blockers despite the use of ACE inhibitors after surgery. Postoperative left ventricular volume was more significantly decreased in beta patients than in non-beta patients despite the use of ACE inhibitors. There were also significant reductions in left ventricular mass index in ACE+beta patients compared to ACE+non-beta patients. However, there were no significant differences in NYHA functional class and survival rate between beta patients and non-beta patients. CONCLUSIONS: beta-blocker therapy may improve cardiac performance by reducing cardiac volume and mass in patients with impaired LV function after AVR for AR.

Adrenergic beta-Antagonists↗
PubMed2000

Coronary surgery through partial sternotomy in a patient with tracheostoma.

We report successful coronary artery bypass grafting through a lower partial sternotomy for a patient with a tracheostoma. He required a tracheotomy for serious laryngeal edema which developed during anesthetic induction prior to elective conventional coronary surgery. A safe alternative approach, comprising a lower midline skin incision with a lower partial sternotomy distant from the stoma, facilitated coronary artery bypass grafting to the left and right coronary arteries after four weeks.

Coronary Artery Bypass↗
PubMed2000

Repeated procedure after radical surgery for tetralogy of Fallot.

BACKGROUND: Although the immediate results of radical operation for tetralogy of Fallot are excellent, long-term follow-up has shown that the number of repeated procedures has increased in many institutions. We describe patients who underwent a second or third procedure after radical operation for tetralogy of Fallot. METHODS: Between April 1981 and August 1996, we operated on 44 patients for the second time and on 4 for the third time after radical operation for tetralogy of Fallot. Indications for a second and third procedure included right ventricular outflow tract obstruction in 38 patients, infective endocarditis in 4, and isolated residual ventricular septal defect in 3. RESULTS: One patient died after concomitant replacement of the pulmonary and tricuspid valves. Three patients who underwent sternotomy more than twice (before the second or third operation) underwent accidental cardiovascular trauma during this procedure (30%). Moreover, when patients underwent more than two sternotomy procedures before the repeated operation for tetralogy of Fallot, the total bypass time, interval between cessation of the cardiopulmonary pump to completion of the operation, amount of blood transfusion, and length of intensive care unit stay were significantly higher compared with those who underwent less than two sternotomy procedures (p < 0.05). Right ventricular outflow tract obstruction was the main indication for a second operation. After the second operation for right ventricular outflow tract obstruction in 35 patients, the preoperative right ventricle to left ventricle pressure ratio decreased significantly (from 0.75 +/- 0.13 to 0.51 +/- 0.12; p < 0.0001). However, the right ventricle to left ventricle pressure ratio did not significantly decrease in patients who underwent a third procedure to treat right ventricular outflow tract obstruction. CONCLUSIONS: The surgical results of a second procedure after radical operation for tetralogy of Fallot were acceptable. However, the risk of accidental cardiovascular trauma during dissection was high among patients who underwent sternotomy more than twice before repeat operation.

Adolescent↗
PubMed2000

Two different techniques of retrograde cerebral perfusion for thoracic aortic surgery through a left thoracotomy.

The authors used profound hypothermic circulatory arrest and continuous retrograde cerebral perfusion for aortic surgery that involved the distal arch through a left thoracotomy. For the first seven patients, oxygenated blood from cardiopulmonary bypass was perfused retrogradely through a venous cannula positioned into the right atrium. In the last 11 cases, venous blood, provided by a perfusion from the lower body, was circulated passively in the brain with the descending aorta clamped. The period of profound hypothermic circulatory arrest was 34.6 +/- 11.1 min, and continuous retrograde cerebral perfusion was 31.3 +/- 11.1 min. Seventeen patients survived, but there was one early death. Two patients with a severely atherosclerotic aneurysm developed permanent neurological dysfunction. The combination of profound hypothermic circulatory arrest, continuous retrograde cerebral perfusion and open aortic anastomosis through a left thoracotomy protects the brain adequately, and facilitates evacuation of debris and air in the aortic arch. It produces satisfactory results for aortic surgery that involves the distal arch.

Aged↗
PubMed2000

Purification and characterization of organic solvent-stable lipase from organic solvent-tolerant Pseudomonas aeruginosa LST-03.

An organic solvent-stable lipase (LST-03 lipase) secreted into the culture broth of the organic solvent-tolerant Pseudomonas aeruginosa LST-03 was purified by ion-exchange and hydrophobic interaction chromatography in the presence of 2-propanol. The purified enzyme was homogeneous as determined by SDS-PAGE. The molecular mass of the lipase was estimated to be 27.1 kDa by SDS-PAGE and 36 kDa by gel filtration. The optimum pH and temperature were 6.0 and 37 degrees C. LST-03 lipase was stable at pH 5-8 and below 40 degrees C. Its hydrolytic activity was highest against tricaproin (C6), methyl octanoate (C8), and coconut oil respectively among the triacylglycerols, fatty acid methyl esters, and natural oils investigated. The enzyme cleaved not only the 1,3-positioned ester bonds, but also the 2-positioned ester bond of triolein. It exhibited high levels of activity in the presence of n-decane, n-octane, DMSO, and DMF as well as in the absence of an organic solvent. In addition, LST-03 lipase was stabler in the presence of n-decane, ethyleneglycol, DMSO, n-octane, n-heptane, isooctane, and cyclohexane than in the absence of an organic solvent.

Journal Article↗
PubMed2000

Sequential activation of transcription factors in lens induction.

Since the pioneering work of the early 1900s, the lens has been used as a model system for the study of tissue development in vertebrates. A number of embryological transplantation experiments designed to elucidate the role of tissue interactions in the formation of the lens have led to the proposal of a stepwise determination model. This model has recently been refined through the identification of certain transcription factor genes, which exhibit distinct expression patterns and functional properties in the lens cell lineage. Otx2, Pax6, and Lens1 are induced by the adjacent anterior neural plate and expressed in predifferentiated lens ectoderm. Contact between the optic vesicle and lens ectoderm promotes expression of mafs, Soxs, and Prox1, which are responsible for the initiation of lens differentiation programs including crystallin expression, cell elongation, and cell cycle arrest. Further analysis of the expression and functional characteristics of these transcription factors will allow greater detail when describing the orchestration of genetic programs, which control tissue development from induction to maturation.

Animals↗
PubMed2000

The Koga Hospital Center for studies on sleep: status report.

Between September 1996 and January 1999 we used polysomnography (PSG) to examine 473 patients (involving a total of 662 records). The diagnosis was a sleep-related breathing disorder in 256 patients, including sleep apnea syndrome (SAS) in 194 patients, sleep hypoxicemia in 18 and insomnia in the other four. The SAS consisted of three subtypes: central apnea (CA) in 56 patients, obstructive apnea (OA) in 124 and mixed apnea (MA) in eight. The ratio of central apnea was relatively higher than the national average. Among the 473 patients, the most common complication was heart disease (133 patients) while other complications included hypertension, and respiratory and cerebrovascular diseases. Concerning the therapy for these patients, continuous positive airway pressure therapy was the most commonly applied and was effective in each type of SAS (CA, OA, MA). Other therapies included prosthetic mandibular advancement, bilevel positive airway pressure, medication and ENT operations. In Koga Hospital, there are many patients with heart disease and/or respiratory disease. We examined those patients who presented with snoring and/or apnea using PSG. Among these patients, SAS was the most common sleep disorder. The relative ratio of CA was high and the average age was higher than those with OA.

Adult↗