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T Shida

Publications and source records attributed to T Shida.

At least 19 recordsLinked to original sources
PubMed2001

Mutational analysis of catalytic sites of the cell wall lytic N-acetylmuramoyl-L-alanine amidases CwlC and CwlV.

The Bacillus subtilis CwlC and the Bacillus polymyxa var. colistinus CwlV are the cell wall lytic N-acetylmuramoyl-l-alanine amidases in the CwlB (LytC) family. Deletion in the CwlC amidase from the C terminus to residue 177 did not change the amidase activity. However, when the deletion was extended slightly toward the N terminus, the amidase activity was entirely lost. Further, the N-terminal deletion mutant without the first 19 amino acids did not have the amidase activity. These results indicate that the N-terminal half (residues 1-176) of the CwlC amidase, the region homologous to the truncated CwlV (CwlVt), is a catalytic domain. Site-directed mutagenesis was performed on 20 highly conserved amino acid residues within the catalytic domain of CwlC. The amidase activity was lost completely on single amino acid substitutions at two residues (Glu-24 and Glu-141). Similarly, the substitution of the two glutamic acid residues (E26Q and E142Q) of the truncated CwlV (CwlV1), which corresponded to Glu-24 and Glu-141 of CwlC, was critical to the amidase activity. The EDTA-treated CwlV1 did not have amidase activity. The amidase activity of the EDTA-treated CwlV1 was restored by the addition of Zn2+, Mn2+, and Co2+ but not by the addition of Mg2+ and Ca2+. These results suggest that the amidases in the CwlB family are zinc amidases containing two glutamic acids as catalytic residues.

Amino Acid Sequence↗
PubMed2001

Mitral valve replacement through right thoracotomy after coronary arterial bypass grafting with functioning conduits.

A 67-year-old man who had undergone coronary artery bypass grafting 3 years previously suffered from severe mitral regurgitation associated with Streptococcal infective endocarditis. He was placed in New York Heart Association functional class III. Preoperative angiography demonstrated good opacification of all 3 conduits implanted in the previous operation. We replaced the mitral valve through an anterolateral right thoracotomy, approaching the mitral valve as an alternative to redoing sternotomy to minimize potential injury to patent grafts. His postoperative course was uneventful. After a 1-month course of antibiotics, the patient was discharged as New York Heart Association class II and at present, 3 months after discharge, is doing well. This approach is an effective alternative to redoing sternotomy for mitral valve operation, especially in patients undergoing a previous coronary arterial bypass grafting via median sternotomy.

Aged↗
PubMed2001

Early results of coronary grafting using ultrasonically skeletonized internal thoracic arteries.

BACKGROUND: We have developed an ultrasonic complete skeletonization technique for obtaining internal thoracic artery (ITA) grafts and have used this method clinically since January 1998. In this report, we discuss the early results of bilateral ITA grafts obtained with our method. METHODS: We studied 200 consecutive patients who underwent coronary artery bypass grafting using ITAs obtained by this technique. Angiography of the grafts was performed in 188 patients (94%) within 1 month after coronary artery bypass grafting. RESULTS: The ITA grafts were about 4 cm longer than pedicled ITA grafts. The free flow through the grafts was at least 30% higher than through pedicled ITAs. The early patency rate determined by postoperative angiography of the grafts was 99.7% for left ITAs and 100% for right ITAs. No patient required postoperative intervention or repeated surgery. CONCLUSIONS: Ultrasonic complete skeletonization increases the effective length of ITA bypasses, improves free flow through the bypasses, and it is less invasive than conventional pedicled harvesting. These excellent early results indicate that this technique is a straightforward, safe, less invasive, and optimal method for obtaining ITA bypass grafts.

Adult↗
PubMed2000

Accumulation of an artificial cell wall-binding lipase by Bacillus subtilis wprA and/or sigD mutants.

A recombinant lipase, CWB-LipB, localized on the Bacillus subtilis cell surface and retaining lipase activity was unstable and not accumulated in a high yield. To improve the accumulation, we examined cell wall binding protease (wprA)- and/or sigma D (sigD)-deficient mutants, and also a NprE and AprA protease-deficient mutant as host strains. The nprE aprA mutation did not lead to a significant increase in the CWB-LipB accumulation. The wprA mutant accumulated a greater amount than the wild-type only in the stationary phase, but the sigD mutant accumulated a greater amount in both the exponential and stationary phases. The double mutant exhibited great accumulation of CWB-LipB, the amount being 36% of the total proteins extracted from the cell surface.

Bacillus subtilis↗
PubMed2000

Primary osteosarcoma of heart with severe congestive heart failure.

We present a case report on a 54-year-old woman with extraskeletal osteosarcoma of the left atrium featuring severe congestive heart failure. We resected the tumor, which occupied the left atrium and had widely infiltrated the atrial wall, but the patients died of the tumor 9 months after surgery. This is to our knowledge the 32nd case of cardiac osteosarcoma ever reported.

Female↗
PubMed2000

Histologic and physiologic evaluation of skeletonized internal thoracic artery harvesting with an ultrasonic scalpel.

OBJECTIVES: The safety and reliability of a method of skeletonized internal thoracic artery harvesting with an ultrasonic scalpel (Harmonic Scalpel; Ethicon Endo-Surgery, CVG, Cincinnati, Ohio) were evaluated. METHODS: The mural branches of the internal thoracic artery were cut by means of 3 methods, differentiated by distance from the site of application of the Harmonic Scalpel blade to the internal thoracic artery. A total of 15 branches were cut from the internal thoracic artery at (0 mm) the origin (group I) or at 1 mm (group II) or 2 mm (group III) distal to the origin. Tissue preparations were examined for successful vessel closure and severity of tissue damage. The length of stump (L) and the length of tissue damage from the stump (D) were determined by a computer image analysis system, and pressure testing was performed to evaluate the physical strength of vessel closure. RESULTS: In group I, 8 of the 15 branches exhibited discontinuity of the vascular wall structure, probably because of insufficient sealing of the divided section, and 12 of the 15 branches exhibited tissue denaturation on the internal thoracic artery wall adjacent to areas of origin, which was probably caused by the heat transferred from the branches during the process of coagulation. In groups II and III, continuity of wall structure of stumps suggestive of stable closure of branches was confirmed. The lengths of tissue damage from the stump (D) were 0.96, 0.58, and 0.63 mm in groups I, II, and III, respectively, and the lengths of intact area (L - D) in the corresponding groups were -0.78, 0.61, and 1.51 mm. The negative figure in group I indicates the presence of tissue damage in the internal thoracic artery itself. By contrast, in groups II and III the internal thoracic arteries were intact, with a safety margin of greater than 0.5 mm. On physiologic evaluation of vessel closure, 2 of the 24 (8.3%) branches burst under a pressure lower than 350 mm Hg because of insufficient vessel coagulation, but the remaining 22 branches (91.7%) remained intact under pressures up to 350 mm Hg. CONCLUSION: The internal thoracic artery skeletonization method with an ultrasonic scalpel (Harmonic Scalpel: output level 2) appears to be a safe and reliable method of skeletonized internal thoracic artery harvesting when branches are sectioned at least 1 mm distal to their origin at a sufficiently slow speed.

Animals↗
PubMed2000

Overexpression, purification, and characterization of Bacillus subtilis N-acetylmuramoyl-L-alanine amidase CwlC.

N-acetylmuramoyl-L-alanine amidase CwlC of Bacillus subtilis was overproduced in Escherichia coli and purified 21-fold. The amidase hydrolyzed type A cell walls such as B. subtilis. The amidase bound slightly to the Microbacterium lacticum cell wall (type B), but did not entirely hydrolyze it. The presence of calcium or magnesium ion increased the resistance of the amidase to heat denaturation.

Animals↗
PubMed2000

A canine case of partial heterotaxia detected by radiography and ultrasound.

With radiography and ultrasound, reversed positioning of the fundus ventriculi and pylorus, a duodenum running on the left side, transposition of the kidneys, and normal thoracic organs were found in a 5-month-old miniature dachshund that presented with anorexia and weight loss. The case was diagnosed as partial heterotaxia. Gross observation revealed partial heterotaxia, polysplenia, abnormal lobulation of the liver, and absence of the greater omentum. These findings were consistent with those observed in asplenia-polysplenia syndrome in humans.

Animals↗
PubMed2000

Coronary artery bypass grafting using the "Super Pulse" dynamic pulsatile cardiopulmonary bypass device in patients with cerebrovascular occlusive disease.

Patients with coronary disease complicated by severe carotid or intracranial arterial stenosis underwent coronary artery bypass graft surgery (CABG) using a novel method of dynamic pulsatile cardiopulmonary bypass (Super Pulse CPB). The Super Pulse technique can maintain the systolic pressure and systolic-diastolic amplitude in such a way that they mimic the physiologic circulation. Forty-five patients (33 males and 12 females, mean age 65.1 years) with coronary disease who had a greater than 75% stenosis of the carotid or intracranial arteries were evaluated. Evaluation was performed for the following 3 groups: 8 patients with conventional pulsatile CPB (Group I), 8 patients with conventional pulsatile CPB plus intraaortic balloon pumping (Group II), and 29 patients with Super Pulse CPB. Maximum, minimum, and mean perfusion pressures during CPB were 112.7, 53.6, and 76.9 mmHg (integrated mean), respectively, in Group III. The systolic-diastolic amplitude was significantly better than for Group I and similar to baseline pressures. No patients in Group II or Group III developed perioperative cerebral disorders or myocardial infarction, while in Group I perioperative cerebral disorders developed in 3 patients, myocardial infarction occurred in 2 patients, and 2 patients died during hospitalization. The initial performance of the Super Pulse CPB indicates excellent safety, and is useful for patients with co-morbid cerebral arterial disease.

Aged↗
PubMed2000

[Management of coronary artery disease combined with aortic stenosis: how to do with mild aortic stenosis].

A total of fourteen patients with combined operation of coronary artery bypass grafting (CABG) and aortic valve replacement (AVR) for coronary artery disease (CAD) and aortic stenosis (AS) were reviewed to evaluate the indication of the combined operation. Preoperative pressure gradient across the valve and effective orifice area were 21-89 mmHg (mean 64 mmHg), 0.5-1.9 cm2 (mean 0.92 cm2), respectively. The extent of CAD was 1-3 (mean 2.0). Fractional shortening (%FS) ranged from 13% to 43% with mean value of 28%. All patients underwent CABG and AVR. The number of grafts was 1-4 (mean 2.3) with internal thoracic artery used in 7 cases. Mechanical valves were employed for all patients except 1 case with cerebral aneurysm. There was no operative death, although low output syndrome developed in 2 cases. One had poor left ventricular function preoperatively, and the other was emergency case. Fractional shortening improved postoperatively even in two cases with preoperative %FS less than 20%, and all grafts were patent on postoperative coronary angiography. The event-free survival was 100% during 32 months of mean follow-up. Combined AVR with CABG is recommended to avoid risky secondary operation in patients of CAD and AS, even if one of which is relatively mild, because of the fact that operative and late results of the combined surgery are satisfactory.

Adult↗
PubMed2000

[Change in skin reactivity to common allergens in allergic patients over a 30-year period. Association with aeroallergen load].

Five-year changes in the percentage of positive intradermal test to allergens in patients with bronchial asthma (BA) and allergic rhinitis (AR) over a period of 30 years from 1969 to 1998 were analyzed, with consideration of their association with the yearly changes in the levels of airborne pollens and molds over 30 years. Allergens used throughout the period were house dust, pollens from various plants (Japanese cedar, pine, oak, Japanese alder, Zelkova, orchard grass, ragweed, mugwort and Japanese hop) and molds (Alternaria, Cladosporium, Aspergillus, Penicillium and Candida). Overall percentages to house dust were higher in BA patients than in AR patients, but those to pollens were distinctly higher in the latter. Those to molds were higher in BA patients, except that those to Alternaria were about the same in both BA and AR patients. Therefore, the clinical expression of allergy may differ according to the type of allergen to which subjects are sensitized. Over the course of 30 years, the increase in the percentage of positive intradermal test to all of the allergens used was noted in both BA and AR patients, although this did not always reflect the aeroallergen load. This includes the two extremes to pollens from Japanese cedar and pine, either of which is the most common source of allergen in Japan. Significant increases in the percentages to Japanese cedar pollen (from 12.5% to 54.4% in BA patients, and from 35.1% to 81.5% in AR patients) appeared to be roughly correlated to marked increases in pollen count. In contrast, that to pine pollen was kept low at about 2%, because of their weak allergenicity, but abruptly increased to 5-6% in the last decade, despite the almost invariable pollen count over the last 30 years. Therefore, the increased sensitivity to aeroallergens may also be associated with other factors besides their load in the air.

Adult↗
PubMed1999

Abasic site recognition mechanism by the Escherichia coli exonuclease III.

In order to elucidate the mechanism of AP site recognition by Echerichia coli exonuclease III (exoIII), site-directed mutagenesis of the Tyr109, the Trp212, and the Phe213 residues, which were conserved in the type II AP endonuclease from various organisms and located in the vicinity of the catalytic site, was performed. The exoIII-W212S mutant lacked any detectable AP endonuclease activity and binding ability to the duplex DNA containing an AP site, while the exoIII-Y109S and exoIII-F213W mutants retained a low level of activities (13% and 83%, respectively, compared with wild-type exoIII). This study suggests that the Trp212 is an important component for abasic site recognition by the E. coli exonuclease III.

Amino Acid Substitution↗
PubMed1999

Characterization of Bacillus subtilis ExoA protein: a multifunctional DNA-repair enzyme similar to the Escherichia coli exonuclease III.

To discover the physiological role of the Bacillus subtilis ExoA protein, which is similar in amino acid sequence to Escherichia coli exonuclease III, an exoA::Cm disruption was constructed in the chromosomal DNA of B. subtilis. There was no clear difference in tolerance to hydrogen peroxide and alkylating agents between the disruptant and the wild type strain. An expression plasmid of the ExoA in E. coli was constructed by inserting the exoA gene into the expression vector pKP1500. The purified ExoA was used to clarify enzymatic characterizations using synthetic DNA oligomers as substrates. A DNA oligomer containing a 1', 2'-dideoxyribose residue as an AP site, a DNA-RNA chimera oligomer, and a 3' end 32P-labeled oligomer were synthesized. It has been shown that the ExoA has AP endonuclease, 3'-5' exonuclease, ribonuclease H, and 3'-phosphomonoesterase activities. Thus, it has been confirmed that ExoA is a multifunctional DNA-repair enzyme in B. subtilis that is very similar to E. coli exonuclease III except that ExoA has lower 3'-5' exonuclease activity than that of E. coli exonuclease III.

Bacillus subtilis↗
PubMed1999

Serum alpha-fetoprotein values in dogs with various hepatic diseases.

Serum alpha-fetoprotein (AFP) values were measured in hepatic diseased dogs with or without tumor and non-hepatic tumor bearing dogs by a sandwich ELISA using anti-dog AFP antiserum. Serum AFP values were less than 70 ng/ml in clinically healthy dogs. The values in dogs with hepatocellular carcinoma were higher than 1,400 ng/ml in 7 of 9 dogs, wherever those in two dogs with cholangiocarcinoma were in the normal range. Serum AFP values in hepatic diseased dogs without tumor were also high, however, the values were below 500 ng/ml in 90% of the dogs. In non-hepatic tumor dogs, serum AFP values were less than 500 ng/ml in 76% of the dogs. In the surgically removal cases with hepatocellular carcinoma, serum AFP values rapidly decreased. These results suggested that the sandwich ELISA using anti-dog AFP antiserum was an available method for diagnosis of hepatocellular carcinoma in dogs.

Animals↗
PubMed1999

Vinylamycin, a new depsipeptide antibiotic, from Streptomyces sp.

A new depsipeptide antibiotic, vinylamycin, was isolated from the culture broth of an actinomycete strain. The producing organism, designated MI982-63F1, was identified as a member of Streptomyces. Vinylamycin was isolated from the culture broth by extraction with EtOAc and purified by crystallization from EtOAc. The structure of vinylamycin was determined by spectroscopic analysis and degradation studies. Vinylamycin showed antimicrobial activities against Gram-positive bacteria including MRSA.

Animals↗
PubMed1999

[Predonation and transfusion in open heart surgery].

The efficacy of predonation of autologous blood in reducing the use homologous blood during open heart surgery was investigated. Between January 1997, and February 1998, predonation and transfusion was studied in 100 consecutive open heart operations (CABG, 77; valve surgery, 17; ASD, 5; myxoma, 1). The guidelines for autologous predonation were as follows: an age < 70 years, a weight > 40 kg and a hemoglobin > 12 g/dl. Patients in NYHA class IV or undergoing emergency operation were excluded. The blood loss during operation ranged from 195 to 1,850 ml (mean; 670 ml), being from 305 to 1,850 ml (723 ml) for CABG, from 260 to 1,020 ml (493.5 ml) for valve surgery and from 195 to 570 ml (342 ml) for ASD. The blood loss was not significantly dependent on sex or age and did not differ elective and emergent operations. Only 36.6% of patients with autologous predonation needed homologous transfusion versus 63.4% of those without predonation. Homologous transfusion was done in only 5% of the those with predonation of 800 ml versus 69% at 400 ml and 71% at 200 ml. In conclusion, autologous blood transfusion is effective for reducing the homologous blood requirement. It also seems that predonation of 800 ml may be sufficient to allow open heart surgery without blood transfusion.

Adolescent↗