951
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Shirai J, Maeda M, Fujii M, Kuniyoshi S. Swollen head syndrome is not associated with turkey rhinotracheitis virus. Vet Rec 1993; 132:41-2. [PMID: 8442337 DOI: 10.1136/vr.132.2.41] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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952
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Kleinerman ES, Maeda M, Jaffe N. Liposome-encapsulated muramyl tripeptide: a new biologic response modifier for the treatment of osteosarcoma. Cancer Treat Res 1993; 62:101-107. [PMID: 8096724 DOI: 10.1007/978-1-4615-3518-8_14] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
We have demonstrated that monocytes from osteosarcoma patients can be rendered tumor cytotoxic by both in vitro incubation with liposomal MTP-PE and i.v. administration of this agent. Chemotherapy did not interfere with this activation process. We have further demonstrated in phase I and phase II trials that liposomal MTP-PE can be given safely i.v. to both adults and children with minimal side effects. The findings of peripheral fibrosis with neovascularization and infiltration of the tumor with chronic inflammatory cells after liposomal MTP-PE therapy are unlike any observed following chemotherapy or surgery. Subsequent to chemotherapy, osteosarcoma lung metastases usually exhibit a zone of central necrosis, with viable tumor cells growing at the periphery of the lesion. However, in our patients following liposomal MTP-PE viable tumor cells were observed in the center of the lesion, with necrosis and fibrosis at the periphery. These changes were thus interpreted as a specific response to liposomal MTP-PE. The peripheral fibrosis observed in these tumors is reminiscent of the appearance of pulmonary tuberculosis lesions. Initially, the lesion is walled off and slow necrosis proceeds from the outside so that the lesion is replaced by fibrous tissue. Eradication of tuberculosis by chronic inflammation is a slow process. Viable bacilli can persist for months. Thus, our choice of a 3-month treatment course may have been insufficient. We have now extended our protocol to allow 6 months of therapy. Osteosarcoma appears to be an ideal disease in which to employ liposomal MTP-PE as an additional adjuvant to present chemotherapy regimens.(ABSTRACT TRUNCATED AT 250 WORDS)
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953
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Teranishi K, Murase M, Maeda M, Murakami F. [A case of acute hemorrhagic gangrenous acalculous cholecystitis with bile peritonitis during anti-coagulant therapy after coronary-artery bypass grafting]. [ZASSHI] [JOURNAL]. NIHON KYOBU GEKA GAKKAI 1993; 41:83-87. [PMID: 8459151] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Acute acalculous cholecystitis is a relatively rare complication occurring after surgery on organs other than the bile duct system. It is often misinterpreted to be a post-operative symptom, and can progress into a very serious condition with high risk of mortality if gangrene and perforation develop. Its occurrence after open heart surgery is relatively rare. We experienced a case of acute hemorrhagic, gangrenous acalculous cholecystitis that developed after coronary-artery bypass grafting. The patient, a 78-year-old man, complained post-operatively of a right upper abdominal pain. The diagnosis of acute gangrenous acalculous cholecystitis was established on the basis of abdominal sonography and CT, and emergency operation performed was successful. Etiological factors in this case may have included post-operative stasis of bile, swelling of the gallbladder, hypotension during cardiopulmonary bypass, and post-operative anti-coagulant therapy administered after open heart surgery. These factors induced intracystic hemorrhage followed by sudden exacerbation, which resulted in gangrenous cholecystitis followed by perforative biliary peritonitis.
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954
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Nakamoto R, Maeda M, Futai M. The gamma subunit of the Escherichia coli ATP synthase. Mutations in the carboxyl-terminal region restore energy coupling to the amino-terminal mutant gamma Met-23–>Lys. J Biol Chem 1993. [DOI: 10.1016/s0021-9258(18)54014-x] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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955
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Murase M, Maeda M, Koyama T, Tomida Y, Murakami F, Teranishi K, Ogawa Y, Seki A, Okamoto H, Hoshino M. Continuous retrograde cerebral perfusion for protection of the brain during aortic arch surgery. Eur J Cardiothorac Surg 1993; 7:597-600. [PMID: 8297613 DOI: 10.1016/1010-7940(93)90246-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Hypothermic circulatory arrest and selective cerebral perfusion for aortic arch surgery have been reported, but these procedures are of limited duration, require hazardous and complicated techniques and can cause clamp injury. Continuous retrograde cerebral perfusion (CRCP) is a new and simple technique for the protection of the brain during hypothermic circulatory arrest. We applied CRCP in 26 patients who underwent aortic arch surgery. Continuous retrograde cerebral perfusion was performed with a mean blood flow of 383 +/- 176, range 120-800, ml/min. The mean duration of CRCP was 63 +/- 15, range 32-92, min with the superior vena cava pressure at 15-42 mm Hg. No neurologic deficit was observed in 20 patients (90%) and only minor deficits in 2 out of the 22 cases without severe postoperative complications, allowing evaluation of the effectiveness of CRCP. Four patients had other severe complications, and the effectiveness of the method could not be evaluated. Continuous retrograde cerebral perfusion can be an excellent and safe technique which avoids clamp injury during aortic arch surgery.
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956
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Usui A, Murase M, Maeda M, Tomita Y, Murakami F, Teranishi K, Koyama T, Ito T, Abe T. Sandwich repair with two sheets of equine pericardial patch for acute posterior post-infarction ventricular septal defect. Eur J Cardiothorac Surg 1993; 7:47-9. [PMID: 8431303 DOI: 10.1016/1010-7940(93)90148-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
A 74-year-old man, who had posterior post-infarction ventricular septal defect, was treated successfully by early surgical repair with a sandwich technique involving two sheets of equine pericardial patch. In this technique the ventricular septal defect (VSD) was exposed through a trans-infarction approach. The inside patch covered the VSD and ventriculotomy from the inside. The outside patch generously covered the infarcted myocardium. The two patches completely sandwiched the infarcted myocardium including the VSD and ventriculotomy with eighteen interrupted sutures. This technique ensures strong fixation of the VSD, reducing the risk of bleeding and recurrence of VSD, and also maintains the proper shape and size of the left ventricle without the danger of ventricular aneurysm formation.
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957
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Fukui A, Maeda M, Tamai S, Inada Y. "Plasmatic imbibition" in the rat musculocutaneous pedicled venous flap: enzymatic proof using horseradish peroxidase. Microsurgery 1993; 14:114-9. [PMID: 7682275 DOI: 10.1002/micr.1920140206] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
To determine the reason for survival of a pedicled venous flap in which only a draining vein is preserved, it is important to clarify what kind of blood flow is present in the preserved draining vein. Pedicled venous flaps were prepared on the dorsum of the rat and histologically evaluated using horseradish peroxidase (HRP). HRP was applied between the flap and recipient bed in one group. In the other group, HRP was injected into the femoral vein after the flap was turned over (to prevent contact with the recipient bed). The flaps in these HRP-treated groups were compared with untreated control groups. HRP applied between the flap and recipient bed was imbibed into the flap and subsequently transferred into the preserved draining vein. HRP that was injected into the femoral vein was also found in the draining vein of the flap. These results suggest that (1) plasmatic imbibition occurs in pedicled venous flaps; and (2) antegrade and retrograde blood flow are present in the draining vein.
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958
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Nagata C, Yoshida H, Mirbod SM, Komura Y, Fujita S, Inaba R, Iwata H, Maeda M, Shikano Y, Ichiki Y. Cutaneous signs (Raynaud's phenomenon, sclerodactylia, and edema of the hands) and hand-arm vibration exposure. Int Arch Occup Environ Health 1993; 64:587-91. [PMID: 8314618 DOI: 10.1007/bf00517705] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Dermatological tests and examinations of the hand(s) were carried out in vibration-exposed and unexposed males. The subjects were 179 chain-saw workers in private forestry companies and 205 local inhabitants who had never used vibrating tools. The prevalences of Raynaud's phenomenon (RP), sclerodactylia, and edema of the hands were estimated in both groups, and associations between these cutaneous signs and vibration exposure were evaluated. The prevalences of RP and edema in the exposed group were 9.5% and 1.7%, respectively, and in the unexposed group, 2.9% and 1.5%, respectively. Sclerodactylia was seen in 31.8% of the chain-saw workers but in only 6.4% of the unexposed individuals. In statistical analyses based on unconditional logistic regression models with adjustment for age, RP was associated with long-term (> or = 20 years) vibration exposure [odds ratio (OR) = 7.06; 95% confidence interval (CI) = 2.51-19.87]. Sclerodactylia was associated with both short- and long-term vibration exposure (OR = 6.54, CI = 3.30-13.36; OR = 7.05; CI = 3.41-14.60, respectively). There were significant dose-response relationships between RP and duration of exposure and between sclerodactylia and duration of exposure. Results of function tests indicated a longer recovery time and a higher vibration threshold for the workers with RP. The presence of sclerodactylia, however, did not have any significant influence on function test results. It is possible to conclude that not only RP but also sclerodactylia could be induced by vibration exposure. However, most cases of sclerodactylia were not so serious as to involve disturbances of peripheral circulatory and nerve function.
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959
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Maeda M, Matubara K, Hirano H, Watabe H, Ichiki Y, Mori S. Pitting scars in progressive systemic sclerosis. Dermatology 1993; 187:104-8. [PMID: 8358096 DOI: 10.1159/000247216] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
The digital pitting scar is a common clinical feature in patients with progressive systemic sclerosis (PSS). Its pathogenesis is unclear, but it may result in small ulcerations. The clinical and histological features of these lesions are poorly understood. Eighty-seven patients with PSS were examined at least once per year. Pitting scars were defined as pinhole-sized digital concave depressions with hyperkeratosis. They were seen in 34 cases (39%) and were located not only on the tips of the fingers, but also on the sides, especially on the radial border of the index and middle finger and the ulnar side of the thumb, where they had a linear arrangement. Additional pitting scars were noticed on the dorsal surface of the proximal interphalangeal and metacarpophalangeal joints. Pitting was closely associated with several signs of PSS, e.g. Raynaud's phenomenon, skin thickening or articular involvement (e.g. stiffness, swelling, pain). There was no relationship between the number of pitting scars and the duration of PSS. Biopsy samples were taken of the lesions on the lateral sides of fingers in 3 patients. Histologically, there was a plug-like hyperkeratosis with parakeratosis, homogenized collagen fibers and slight perivascular mononuclear cell infiltration. Calcification and altered collagen fibers were observed in the deep dermis. Although pitting scars of the fingertips may be different from those of the lateral sides of the fingers, both histologically and pathogenetically, they were similar clinically. The scar locations on the fingertips and finger joints (proximal interphalangeal and metacarpophalangeal) suggest that exogenous trauma, vibration injury and/or cold exposure may play a role in their pathogenesis.
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960
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Fukui A, Maeda M, Tamai S, Inada Y. The pedicled venous flap. Clinical applications. BRITISH JOURNAL OF PLASTIC SURGERY 1993; 46:68-71. [PMID: 8431744 DOI: 10.1016/0007-1226(93)90068-m] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Experimental findings of survival of pedicled venous flaps were clinically applied in seven cases for traumatic skin defects on digits. Five flaps which were transferred to or on digits other than the thumb survived, but two flaps from the index to the thumb developed partial necrosis. In order to prevent flap necrosis, the draining vein should be short.
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961
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Mori S, Maeda M, Matsubara K. [Systemic scleroderma]. NIHON RINSHO. JAPANESE JOURNAL OF CLINICAL MEDICINE 1993; 51 Suppl:527-34. [PMID: 8459583] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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962
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Maeda M, Fukui A, Tamai S, Mii Y, Miura S. Extracorporeal circulation for tissue transplantation (in the case of venous flaps). Plast Reconstr Surg 1993; 91:113-24; discussion 125-6. [PMID: 8416516] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
During free-tissue transplantation, recipient vessels are often crushed as a result of trauma or radiation therapy, making anastomosis of vessels difficult. In some cases, a second operation is unavoidable because of formation of a postoperative thrombus at sites of the anastomosis. To solve such problems, it should be possible to transplant tissue anywhere in the body without vascular anastomosis by extracorporeal circulation. This study mainly concerned venous flaps that were spindle-shaped and 4 x 3 cm in size. One hundred and forty-six male Japanese White rabbits, weighing 2.0 to 2.5 kg, were used. Stabilized hemoglobin, lactated Ringer's solution, whole blood, and plasma were used as perfusate. Each of these perfusates was injected at a rate of 5 ml per hour continuously for 3 days in good recipient sites and for 7 days in poor recipient sites. Five rabbits were used in each group. The flaps were examined histologically and electron microscopically. Moreover, in the plasma group, microangiography was performed to observe blood circulation between the flap and the surrounding tissue. The flaps survived in all cases in which the plasma group had good recipient beds but did not survive in any of the other cases, in which degeneration of the endothelial cells was detected prior to edema. According to the results of this examination, tissue viability of the venous flap could be maintained for at least 3 days by perfusion of plasma. During this time, in the cases of good recipient sites, blood may begin to recirculate between the flap and the surrounding tissue.
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963
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Yamakado T, Ookubo S, Ueda K, Maeda M, Nakano T. [A study of coupling of contraction and relaxation in human left ventricle]. JAPANESE CIRCULATION JOURNAL 1993; 57 Suppl 4:1245-7. [PMID: 7966956 DOI: 10.1253/jcj.57.supplementiv_1245] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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964
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Facure NO, Toniolo CM, Maeda M. [Psychosocial approach of the epileptic patient: analysis of 30 adults]. ARQUIVOS DE NEURO-PSIQUIATRIA 1992; 50:486-90. [PMID: 1309153 DOI: 10.1590/s0004-282x1992000400011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Psychosocial aspects of patient's life were analysed in 30 patients with epilepsy aged over 18 years old. At this age people usually are apt by themselves to exert several psychosocial activities. Professional, familial, social, scholar, affective, sexual and religious activities were evaluated in our group of patients. Results evidence that epileptic patients studied show several kinds of difficulties in their psychosocial adjustment.
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965
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Karasawa Y, Koji T, Maeda M. Occurrence of intraportally-infused urea-15N in the urine of domestic fowl. Br Poult Sci 1992; 33:1095-100. [PMID: 1493556 DOI: 10.1080/00071669208417551] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
1. Measurements were made in situ to determine the occurrence of intraportally infused urea-15N in ureteral urine of the fowl. 2. Of the total amount of infused urea-15N, 15% was excreted intact into the urine (90% of urinary total 15N) whereas 9% remained unchanged in the blood (78% of blood non-protein-15N). 3. The proportions of non-protein-15N in the blood, liver and kidney were 12, 3 and 1%, respectively of the infused 15N. Protein-15N was 3% of that infused in blood and much less in liver and kidney. 4. About 1% of the infused 15N was observed in the urinary uric acid, and 3% of the infused 15N in non-protein N, other than urea, ammonia and glutamine amide N, of blood and liver. 5. No appreciable amounts of 15N were present in ammonia and glutamine amide N of blood, liver or kidney and in uric acid of liver or kidney. 6. The caecal contents contained about 1% of the infused 15N with 15% of this as ammonia-15N. 7. It is concluded that intraportal urea is mostly excreted unchanged into ureteral urine of the fowl.
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966
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Tazawa J, Yamaoka K, Koizumi K, Asahina Y, Kamiyama T, Maeda M, Marumo F, Sato C. [A case of colon angiodysplasia successfully treated with endoscopy]. NIHON SHOKAKIBYO GAKKAI ZASSHI = THE JAPANESE JOURNAL OF GASTRO-ENTEROLOGY 1992; 89:2794-7. [PMID: 1491469] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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967
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Usui A, Kato K, Murase M, Maeda M, Koyama T, Tanaka M, Takeuchi E, Abe T. Manganese-containing superoxide dismutase in blood and urine during open-heart surgery. JAPANESE CIRCULATION JOURNAL 1992; 56:1206-13. [PMID: 1479645 DOI: 10.1253/jcj.56.1206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Concentrations of Manganese-containing superoxide dismutase (Mn-SOD) were measured perioperatively by enzyme immunoassay in serial samples of arterial and coronary sinus blood and urine taken from 18 patients undergoing mitral valve surgery. The mean Mn-SOD concentration in the arterial blood samples was 66.2 (SD 16.1 ng/ml) at induction of anesthesia, increased gradually after reperfusion and peaked on the 2nd post-operative day [150 (SD 58.3) ng/ml]. The mean concentration of Mn-SOD in the coronary sinus blood samples was significantly higher than in the arterial samples only at the 6th hour after reperfusion [97 (SD 21.8) ng/ml vs 90.3 (SD 20.9) ng/ml, p < 0.05]. Although concentrations of Mn-SOD in blood did not increase in 8 patients who underwent midline sternotomy for a mediastinal tumor, they increased dramatically in 3 patients who sustained a perioperative myocardial infarction. During open heart surgery the peak values of plasma Mn-SOD concentrations were correlated to that of plasma creatine kinase-MB concentrations (r = 0.5532, n = 18, p < 05) and cardiac ischemic period (r = 0.5186, n = 18, p < 05). Although the meaning of an increase in plasma Mn-SOD concentrations during open heart surgery is not clarified, it may be released from the heart and anywhere also in the body damaged during cardiopulmonary bypass.
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968
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Nakamoto RK, Shin K, Iwamoto A, Omote H, Maeda M, Futai M. Escherichia coli F0F1-ATPase. Residues involved in catalysis and coupling. Ann N Y Acad Sci 1992; 671:335-43; discussion 343-4. [PMID: 1288330 DOI: 10.1111/j.1749-6632.1992.tb43807.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The molecular biological approach has provided important information toward understanding the complexities of the F0F1 ATPase. This article focuses on our recent results on the ATPase catalytic site contained in the beta subunit and the role of the gamma subunit in regulation of proton transport. We used a combination of affinity labeling and mutagenesis to locate several residues of the alpha and beta subunits in the catalytic site. Adenosine triphosphopyridoxal (AP3-PL) labeled beta Lys-155, beta Lys-201 and alpha Lys-201, suggesting that they are near the gamma-phosphate moiety of ATP. Turning to a mutagenesis approach we demonstrated that the two conserved residues, beta Lys-155 and beta Thr-156 in the glycine-rich sequence, are essential for catalysis. Finally, using pseudorevertant analysis, we positioned residue beta Gly-149 (also in the glycine-rich sequence) in proximity to beta Ser-174, beta Glu-192 (binding site for DCCD), and beta Val-198 (only three residues away from the AP3-PL binding site, beta Lys-201). Genetic studies suggested that the gamma subunit plays a role in regulation of catalysis and its coupling with proton conduction. We found that four mutations in the carboxyl-terminal region (gamma Gln-269-->Leu, gamma Gly-275-->Lys, gamma Thr-277-->end, or frameshift) had similar membrane ATPase activities but different ATP-dependent proton pumping and growth by oxidative phosphorylation. These results suggested a perturbation in the coupling between catalysis and proton translocation. We were able to clearly define the "uncoupling" by introducing mutations in the amino-terminal region of the gamma subunit. We were led to gamma Met-23-->Lys and Arg which resulted in an enzyme still regulated by delta microH+, but with profoundly inefficient coupling between ATPase catalytic sites and proton translocation in both ATP-dependent proton pumping and delta microH(+)-driven ATP synthesis. Second-site mutations in the carboxyl-terminal region of the gamma subunit reversed this effect.
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969
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Uehara T, Takeshita M, Maeda M. Studies on anticoagulant-active arabinan sulfates from the green alga, Codium latum. Carbohydr Res 1992; 235:309-11. [PMID: 1473111 DOI: 10.1016/0008-6215(92)80100-f] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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970
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Fujiwara H, Maeda M, Imai K, Fukuoka M, Yasuda K, Takakura K, Mori T. Human luteal cells express dipeptidyl peptidase IV on the cell surface. J Clin Endocrinol Metab 1992; 75:1352-7. [PMID: 1385470 DOI: 10.1210/jcem.75.5.1385470] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
We previously reported that human theca interna cells and small luteal cells express membrane-bound aminopeptidase N, and suggested that membrane-bound peptidases are involved in folliculogenesis and luteal function by regulating extracellular peptide concentrations. In this study, we examined the expression of dipeptidyl peptidase IV (DPP IV), which is a membrane-bound peptidase and has its catalytic domain at extracellular sites, in human granulosa cells, thecal cells of growing, preovulatory, and atretic follicles, as well as corpora lutea. Indirect immunofluorescence staining of ovarian tissues with specific monoclonal antibodies revealed that DPP IV was present in large and small luteal cells in corpora lutea. DPP IV peptidase activity was also detected histochemically in corpora lutea. In growing, preovulatory, and atretic follicles, there was weak immunoreactivity and DPP IV peptidase activity on luteinized theca interna cells, but not on granulosa cells. The expression of DPP IV on the cell surface of large and small luteal cells was confirmed by indirect immunofluorescence staining of freshly isolated luteal cells. These results indicate that DPP IV is a useful surface differentiation marker of human luteal cells and suggest that peptidases are involved in luteal function.
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971
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Abstract
Synaptic vesicles have important roles in the neural transmission at nerve terminals: the storage and the controlled exocytosis of neurotransmitters. At least two different factors are responsible for the concentration process: the vacuolar-type H(+)-ATPase (V-ATPase), establishing an electrochemical gradient of protons, and specific transport systems for transmitters. We will discuss our recent progress on the energy-transducing systems in synaptic vesicles: (1) structural aspects of V-ATPase; (2) energy coupling of transport of transmitters; (3) reconstitution of transporters; (4) effects of neurotoxins and neuron blocking agents; (5) function of synaptic-vesicle-like microvesicles from endocrine tissues.
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972
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Futai M, Iwamoto A, Omote H, Orita Y, Shin K, Nakamoto RK, Maeda M. Escherichia coli ATP synthase (F-ATPase): catalytic site and regulation of H+ translocation. J Exp Biol 1992; 172:443-9. [PMID: 1337098 DOI: 10.1242/jeb.172.1.443] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
We discuss our recent results on the Escherichia coli F-ATPase, in particular its catalytic site in the beta subunit and regulation of H+ transport by the gamma subunit. Affinity labelling experiments suggest that beta Lys-155 in the glycine-rich sequence is near the gamma-phosphate moiety of ATP bound at the catalytic site. The enzyme loses activity upon introduction of missense mutations in beta Lys-155 or beta Thr-156 and changes catalytic properties upon introduction of other mutations. By analysis of mutations and their pseudo revertants, residues beta Ser-174, beta Glu-192 and beta Val-198 were found to be located near the glycine-rich sequence. The combined approaches of chemical labelling and genetics have been fruitful in visualizing the structure of the catalytic site. Analysis of mutations in the gamma subunit suggests that this subunit has an essential role in coupling catalysis with proton translocation.
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973
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Omote H, Maeda M, Futai M. Effects of mutations of conserved Lys-155 and Thr-156 residues in the phosphate-binding glycine-rich sequence of the F1-ATPase beta subunit of Escherichia coli. J Biol Chem 1992; 267:20571-6. [PMID: 1400377] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
beta Lys-155 in the glycine-rich sequence of the beta subunit of Escherichia coli F1-ATPase has been shown to be near the gamma-phosphate moiety of ATP by affinity labeling (Ida, K., Noumi, T., Maeda, M., Fukui, T., and Futai, M. (1991) J. Biol. Chem. 266, 5424-5429). For examination of the roles of beta Lys-155 and beta Thr-156, mutants (beta Lys-155-->Ala, Ser, or Thr; beta Thr-156-->Ala, Cys, Asp, or Ser; beta Lys-155/beta Thr-156-->beta Thr-155/beta Lys-156; and beta Thr-156/beta Val-157-->beta Ala-156/beta Thr-157) were constructed, and their properties were studied extensively. The beta Ser-156 mutant was active in ATP synthesis and had approximately 1.5-fold higher membrane ATPase activity than the wild type. Other mutants were defective in ATP synthesis, had < 0.1% of the membrane ATPase activity of the wild type, and showed no ATP-dependent formation of an electrochemical proton gradient. The mutants had essentially the same amounts of F1 in their membranes as the wild type. Purified mutant enzymes (beta Ala-155, beta Ser-155, beta Ala-156, and beta Cys-156) showed low rates of multisite (< 0.02% of the wild type) and unisite (< 1.5% of the wild type) catalyses. The k1 values of the mutant enzymes for unisite catalysis were lower than that of the wild type: not detectable with the beta Ala-156 and beta Cys-156 enzymes and 10(2)-fold lower with the beta Ala-155 and beta Ser-155 enzymes. The beta Thr-156-->Ala or Cys enzyme showed an altered response to Mg2+, suggesting that beta Thr-156 may be closely related to Mg2+ binding. These results suggest that beta Lys-155 and beta Thr-156 are essential for catalysis and are possibly located in the catalytic site, although beta Thr-156 could be replaced by a serine residue.
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974
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Shin K, Nakamoto RK, Maeda M, Futai M. F0F1-ATPase gamma subunit mutations perturb the coupling between catalysis and transport. J Biol Chem 1992; 267:20835-9. [PMID: 1400398] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
We introduced mutations to test the function of the conserved amino-terminal region of the gamma subunit from the Escherichia coli ATP synthase (F0F1-ATPase). Plasmid-borne mutant genes were expressed in an uncG strain which is deficient for the gamma subunit (gamma Gln-14-->end). Most of the changes, which were between gamma Ile-19 and gamma Lys-33, gamma Asp-83 and gamma Cys-87, or at gamma Asp-165, had little effect on growth by oxidative phosphorylation, membrane ATPase activity, or H+ pumping. Notable exceptions were gamma Met-23-->Arg or Lys mutations. Strains carrying these mutations grew only very slowly by oxidative phosphorylation. Membranes prepared from the strains had substantial levels of ATPase activity, 100% compared with wild type for gamma Arg-23 and 65% for gamma Lys-23, but formed only 32 and 17%, respectively, of the electrochemical gradient of protons. In contrast, other mutant enzymes with similar ATPase activities (including gamma Met-23-->Asp or Glu) formed H+ gradients like the wild type. Membranes from the gamma Arg-23 and gamma Lys-23 mutants were not passively leaky to protons and had functional F0 sectors. These results suggested that substitution by positively charged side chains at position 23 perturbed the energy coupling. The catalytic sites of the mutant enzymes were still regulated by the electrochemical H+ gradient but were inefficiently coupled to H+ translocation in both ATP-dependent H+ pumping and delta mu H+ driven ATP synthesis.
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Sachiyama T, Anan R, Maeda M, Shimizu K, Arima S, Nakao S, Tanaka H, Ihan N, Takemoto M, Otsuka S. [A case of pseudoxanthoma elasticum with severe coronary lesion treated with coronary bypass surgery]. NIHON NAIKA GAKKAI ZASSHI. THE JOURNAL OF THE JAPANESE SOCIETY OF INTERNAL MEDICINE 1992; 81:1703-5. [PMID: 1469325] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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