[Aortic valve replacement and hemiarch replacement in a patient with a porcelain aorta].

We report a case of aortic valve replacement and hemiarch replacement with reconstruction of the brachiocephalic artery in a patient with a porcelain aorta. A 65-year-old man was admitted to the hospital for aortic stenosis. Computed tomography demonstrated severe aortic calcification and extensive calcification covering a wide area of the aorta. The echocardiography showed a highly calcified aortic valve and a pressure gradient of 109 mmHg across the aortic valve. At surgery, calcification of the ascending aorta was severe and involved its entire circumference. Therefore, 2 cannulae were inserted to the right axillary and right femoral arteries for extracorporeal circulation. We performed replacement of the ascending aorta and hemiarch with reconstruction of the brachiocephalic artery under circulatory arrest and antegrade cerebral perfusion, as well as aortic valve replacement with a 21 mm St. Jude Medical mechanical valve. He had no major cardiac complications during the postoperative course, and was discharged on postoperative day 33.

[Recurrent cardiac myxoma that developed rapidly in a short period].

A 55-year-old woman, who had undergone extirpation of left atrial myxoma 3-years before, was admitted to our hospital with dyspnea. Chest computed tomography revealed a low density mass in the left atrium (LA) with a diameter of 54 mm. Transthoracic echocardiography showed that the mass was attached to the left atrial septal wall and had a pendulum-like movement. We urgently performed an operation for recurrent left atrial myxoma. Through atrial transseptal approach, a huge myxomatus tumor was observed in the LA. The stalk was on the endocardium at the cranial side of the previous autologous pericardial patch. The tumor was completely excised along with the patch. We repaired the disrupted endocardium and performed Dacron patch repair of the atrial septal defect. The patient recovered uneventfully and was discharged 14 days after surgery. The excised tumor was found to be myxoma on pathological examination similar to the previous tumor. We report a case of recurrent left atrial myxoma with rapid growth in a short time period.

[Aortic valve replacement and repeat coronary artery bypass grafting in a patient with a patent internal thoracic artery bypass graft; report of a case].

We report a case of aortic valve replacement and repeat coronary artery bypass grafting in a patient with a patent internal thoracic artery bypass graft. A 77-year-old man, who underwent coronary artery bypass grafting (CABG) 10 years ago, was admitted to the hospital for aortic stenosis and angina pectoris. Transthoracic echocardiography demonstrated severe aortic calcification with an 86 mmHg gradient across the aortic valve. Coronary angiography demonstrated the patency of all grafts and 90% stenosis of the left circumflex coronary artery. At surgery, a full median sternotomy was performed. The adhesions around the heart and great vessels were severe and the left internal thoracic artery (LITA) was found adherent to the heart and sternum. The LITA and saphenous vein graft (SVG) graft were dissected carefully. Retrograde coronary sinus (CS) perfusion was performed with antegrade myocardial protection for cardiac arrest. We performed aortic valve replacement (AVR) with a 17 mm St. Jude Medical Regent Valve and CABG to the circumflex artery with the saphenous vein under cardiopulmonary bypass. His postoperative course was uneventful. He was discharged from our hospital without major complications.

Petrous apex cholesterol granuloma treated via the endoscopic transsphenoidal approach.

Numerous surgical approaches have been used to treat petrous apex cholesterol granulomas. They are usually treated via the transtemporal- or middle fossa approach; some are managed endoscopically. We present a patient treated by the endoscopic transsphenoidal approach and review the literature.

[Embolism of the lower limb caused by native aortic valve thrombosis].

Native aortic valve thrombosis is an uncommon event with heart valve disease, during cardiac catheterization, bacterial endocarditis, or a hypercoagulative state as in antiphospholipid antibody syndrome. We report a case of thrombus formation on a native aortic valve, which was found by the transesophageal echocardiography during thrombectomy of the lower limb. We supposed that the atheromatous plaque of aortic valve was related to thrombus formation.

A comparison of the inflammatory response and the recovery of bowel function between trans- and extraperitoneal approaches of abdominal aortic aneurysmectomy.

AIM: To determine whether surgical stress is less with transperitoneal or extraperitoneal abdominal aortic aneurysmectomy, blood concentrations of inflammatory cytokines and other inflammatory markers with recovery of bowel function were examined. METHODS: Patients who underwent abdominal aortic aneurysmectomy electively via the transperitoneal (T-group; n=15) or the extraperitoneal approach (E-group; n=17) were evaluated. Inflammatory cytokines (interleukin[IL]) IL-6, IL-8, C-reactive protein concentrations, and systemic inflammatory response syndrome score were determined before operation and after operation on days (POD) 1, 3, 7, and 14. Recovery of bowel function was estimated by the time taken for resumption of bowel movement and oral intake, and by the volume of fluid collection from the nasogastric tube. RESULTS: Cytokine (IL-8) concentrations were higher in the T-group than the E-group with significant difference on POD 7 (4.8+/-0.5 versus 3.4+/-0.2 pg/mL, respectively; P=0.02). Recovery of bowel function and oral intake were earlier, and the volume of fluid collection from the nasogastric tube was smaller in the E-group than the T-group significantly. CONCLUSIONS: Early recovery of bowel function and low concentration of inflammatory cytokines suggest that the extraperitoneal approach to the abdominal aorta is less stressful to the transperitoneal approach. Postoperative inflammatory response may mainly depend on damage of the bowel in the operation of the abdominal aortic aneurysm.

[Chondrosarcoma of the chest wall].

We report 2 patients with chondrosarcoma of the chest wall. They were a 67-year-old woman (case 1) with an anterior chest wall tumor and a 68-year-old woman (case 2) with a painful rib tumor. Their computed tomography (CT) both revealed calcified tumors. Case 1 underwent a wide resection by partial sternectomy, with free surgical margins. Case 2 underwent tumor resection with the posterior part of the 3rd rib, with positive surgical margin in the vertebral site, and received adjuvant radiotherapy. Both patients were pathologically diagnosed as having grade II chondrosarcoma. In their postoperative courses, they are free from recurrence. Wide resection is likely to be the key to successful management of chest wall chondrosarcoma.

Morphologic Features of Carotid Plaque Rupture Assessed by Optical Coherence Tomography.

BACKGROUND AND PURPOSE: Rupture of the plaque fibrous cap and subsequent thrombosis are the major causes of stroke. This study evaluated morphologic features of plaque rupture in the carotid artery by using optical coherence tomography in vivo. MATERIALS AND METHODS: Thirty-six carotid plaques with high-grade stenosis were prospectively imaged by optical coherence tomography. "Plaque rupture" was defined as a plaque containing a cavity that had overlying residual fibrous caps. The fibrous cap thickness was measured at its thinnest part for both ruptured and nonruptured plaques. The distance between the minimum fibrous cap thickness site and the bifurcation point was also measured. Optical coherence tomography identified 24 ruptured and 12 nonruptured plaques. RESULTS: Multiple ruptures were observed in 9 (38%) patients: Six patients had 2 ruptures in the same plaque, 2 patients had 3 ruptures in the same plaque, and 1 patient had 5 ruptures in the same plaque. Most (84%) of the fibrous cap disruptions were identified at the plaque shoulder and near the bifurcation point (within a 4.2-mm distance). The median thinnest cap thickness was 80 µm (interquartile range, 70-100 µm), and 95% of ruptured plaques had fibrous caps of <130 µm. Receiver operating characteristic analysis revealed that a fibrous cap thickness of <130 µm was the critical threshold value for plaque rupture in the carotid artery. CONCLUSIONS: Plaque rupture was common in high-grade stenosis and was located at the shoulder of the carotid plaque close to the bifurcation. A cap thickness of <130 µm was the threshold for plaque rupture in the carotid artery.

Variety of laminin expressions in murine neoplastic cell-lines - neuroblastoma na cells produce only laminin-b2 chain.

In the present study, we investigated the expression of laminin in three murine neoplastic cell lines; 3LL-SA (Lewis lung carcinoma), NA (neuroblastoma) and F9 (teratocarcinoma). Both Western and Northern blot analyses demonstrated that parietal endoderm-like F9 expressed three laminin chains A, B1 and B2. On the other hand, 3LL-SA cells synthesized two laminin chains B1 and B2, and NA cells only B2 chain. The analyses of the restriction fragment length polymorphism indicated that the genes for coding regions of all chains were present and grossly intact both in 3LL-SA and in NA just as in F9. These findings suggest that expression of laminin seems to be transcriptionally regulated in each neoplastic cell line specifically. Since these cell lines produce different forms of laminin, they can be used for investigation of the multifunctions of laminin molecule.

Renin inhibits N-acetyl-D-glucosamine 2-epimerase (renin-binding protein).

Renin-binding protein (RnBP) is a highly specific renin inhibitor first isolated from porcine kidney. Our recent studies demonstrated that the human RnBP is the enzyme N-acetyl-D-glucosamine (GlcNAc) 2-epimerase [Takahashi, S. et al. (1999) J. Biochem. 125, 348-353]. We have developed a new assay method for GlcNAc 2-epimerase activity using a system of N-acyl-D-hexosamine oxidase coupled with peroxidase and employed this method to study the effects of renin on GlcNAc 2-epimerase activity. The recombinant human (rh) RnBP existed as a dimer and its GlcNAc 2-epimerase activity was strongly inhibited by the purified renin concomitant with the formation of RnBP-renin heterodimer, so-called high molecular weight (HMW) renin. The renin activity was also inhibited by rhRnBP in a dose-dependent manner. These results indicate that renin is an inhibitor of GlcNAc 2-epimerase, and the renin-RnBP heterodimer HMW renin is an inactive form of both renin and GlcNAc 2-epimerase activities.

Identification of functionally important cysteine residues of the human renin-binding protein as the enzyme N-acetyl-D-glucosamine 2-epimerase.

Renin-binding protein (RnBP) is an endogenous renin inhibitor originally isolated from porcine kidney. It was recently identified as the enzyme N-acetyl-D-glucosamine (GlcNAc) 2-epimerase [Takahashi, S. et al. (1999) J. Biochem. 125, 348-353] and its active site residue was determined to be cysteine 380 by site-directed mutagenesis [Takahashi, S. et al. (1999) J. Biochem. 126, 639-642]. To further investigate the relationship between structure and function of recombinant human (rh) RnBP as a GlcNAc 2-epimerase, we have constructed several C-terminal deletion and multi-cysteine/serine mutants of rhGlcNAc 2-epimerase and expressed them in Escherichia coli cells. The expression was detected by Western blotting using anti-rhRnBP antiserum. The C-terminal deletion mutant, Delta400-417, had approximately 50% activity relative to the wild-type enzyme, but other C-terminal deletion mutants, Delta380-417, Delta386-417, and Delta390-417, had no enzymatic activity. Mutational analysis of multi-cysteine/serine mutants revealed that cysteines 41 and 390 were critical for the activity or stabilization of the enzyme, while cysteine residues in the middle of the enzyme, cysteines 125, 210, 239, and 302, had no essential function in relation to the activity.

Identification of cysteine-380 as the essential residue for the human N-acetyl-D-glucosamine 2-epimerase (renin binding protein).

Renin binding protein (RnBP) is a proteinous renin inhibitor firstly isolated from porcine kidney. Recently, the protein was identified as the enzyme, N-acetyl-D-glucosamine (GlcNAc) 2-epimerase. The GlcNAc 2-epimerase activity of recombinant human RnBP was specifically inhibited by SH-reagents such as N-ethylmaleimide, 5, 5'-dithiobis-2-nitrobenzoate, and iodoacetic acid, indicating that the most probable reactive site is a cysteine residue. To identify the active site residue(s), we have constructed ten cysteine residue mutants (C41S, C66S, C104S, C125S, C210S, C239S, C302S, C380S, C386S, and C390S) for human GlcNAc 2-epimerase and expressed them in Escherichia coli cells. The relative specific activities of C41S, C66S, C125S, C210S, C239S, C302S, C386S, and C390S are nearly the same to that of the wild-type enzyme. The specific activity of the C104S mutant is 26% of that of the wild-type enzyme. The expression of the C380S mutant in E. coli cells was detected on Western blotting, whereas GlcNAc 2-epimerase activity was not detected in the extract. These results indicate that Cys380 is essential for the enzymatic activity of human GlcNAc 2-epimerase.

Human renin-binding protein is the enzyme N-acetyl-D-glucosamine 2-epimerase.

The existence of human renin-binding protein (RnBP) in the kidney has been shown by the isolation and characterization of a complex of porcine renin-human RnBP [S. Takahashi et al. (1985) J. Biochem. 97, 671-677]. However, the properties of the free form of human RnBP had not been understood, because of the limitation of materials. In the present study, we have expressed human RnBP in Escherichia coli JM 109 cells under the transcriptional control of taq promoter and purified it by conventional column chromatographies. The purified recombinant human RnBP (rhRnBP) exists as a dimer and inhibits porcine renin activity through formation of a complex of porcine renin with rhRnBP, the so-called high-molecular-weight renin. Moreover, the rhRnBP catalyzes the interconversion between N-acetyl-D-glucosamine (GlcNAc) and N-acetyl-D-Mannosamine (ManNAc) with the apparent Km values of 21.3 mM for GlcNAc and 12.8 mM for ManNAc, and 0.13 mM for effector ATP. ATP is essential for the GlcNAc 2-epimerase activity of human RnBP. These results indicate that the human RnBP is a GlcNAc 2-epimerase.

Blood supply of the parathyroid gland from the superior thyroid artery.

BACKGROUND: There is considerable controversy about the arterial supply to the superior parathyroid glands. Knowledge of this blood supply should be important for the surgeon performing thyroid and parathyroid operations. The purpose of this investigation was to document whether the superior parathyroid glands receive their blood supply from the superior thyroid artery. METHODS: We injected contrast material into the superior thyroid artery in 52 cadavers and determined the arterial blood supply to the parathyroid glands by using a dissecting microscope. RESULTS: The upper parathyroid gland was identified in 51 instances and the upper and lower glands in 26 instances on the side of injection. Of 92 parathyroid glands identified, 57 glands (62%) had a single artery, 26 (28%) had two, and 9 (10%) had three or more arteries. In 9 (45%) of the 20 cases specifically examined, a distinct anastomosing branch was identified between the inferior and the superior thyroid arteries, from which the upper parathyroid artery arose. CONCLUSIONS: Our study documented that the superior thyroid artery almost always supplies the upper parathyroid glands. Forty-five percent of the subjects had a distinct anastomosing branch between the superior and inferior thyroid arteries, which should be kept intact at operation to preserve the upper parathyroid function. One third of the parathyroid glands have two or more parathyroid arteries.

Long-term results of the anterior floating method for cervical myelopathy caused by ossification of the posterior longitudinal ligament.

STUDY DESIGN: Results of the anterior floating method used to decompress ossification of the posterior longitudinal ligament were studied for an average postoperative interval of 13 years. OBJECTIVE: To investigate the long-term results of the anterior floating method used to manage ossification of the posterior longitudinal ligament. SUMMARY OF BACKGROUND DATA: The anterior floating method is a technique that differs from the extirpation method used to manage ossification of the posterior longitudinal ligament. Reports of the long-term results from anterior decompression used to manage cervical ossification of the posterior longitudinal ligament are rare. METHODS: The anterior floating method was used to decompress cervical ossification of the posterior longitudinal ligament in 63 patients. These patients were followed for more than 10 years with neurologic evaluations using a scoring system proposed by the Japanese Orthopedic Association (JOA score). RESULTS: The recovery rate was 66.5% at 10 years and 59.3% at 13 years, the time of the final survey. Operative outcomes most closely reflected the preoperative duration and severity of myelopathy (JOA score) and the preoperative cross-sectional area of the spinal cord. There was no correlation with the canal narrowing ratio or the thickness of ossification of the posterior longitudinal ligament. Delayed deterioration was attributed to an original inadequate decompression and progression of ossification of the posterior longitudinal ligament outside the original operative field. There was no evidence of significant recurrent ossification of the posterior longitudinal ligament within the margins of prior decompression. CONCLUSIONS: The anterior floating method appears to yield adequate long-term outcomes when used to manage ossification of the posterior longitudinal ligament.

Non-genetic group specific component (GC) observed in a patient with acute non-lymphocytic leukemia.

This is the case of a male non-lymphocytic leukemia patient who continuously exhibited non-genetic group specific component (GC). The patient was hospitalized 10 months for treatment. The patient's GC type was GC 2-1A2 upon his admission to the hospital, which was consistent with his parents' type. The additional GC protein isoform appeared during treatment and was detected by polyacrylamide gel isoelectric focusing (PAGIEF). This acquired GC component corresponded to GC 1F in PAGIEF and was thought to have originated from GC 1A2 protein. This phenomenon most probably occurred due to a metabolic abnormality or modification of the GC molecule caused by the disease itself, or by chemotherapy.

Stimulation of saccharifying enzyme production by immobilized fungal mycelia using liquefied rice treated with protease.

The effects of protease-treated liquefied rice on the production of saccharifying enzyme by immobilized fungal mycelia were investigated. The production of saccharifying enzyme by immobilized fungal mycelia was stimulated by the protease-treated liquefied rice. The origin of the effector was identified as a hydrolyzate of glutelin, a major rice protein. Moreover, the effector was purified by gel permeation chromatography and reversed-phase HPLC. The molecular weight of the purified effector was around 400-500 Da and it was composed of a few amino acids. These results indicate that the oligopeptide derived from the glutelin hydrolyzate regulates the production of saccharifying enzyme by immobilized fungal mycelia. Furthermore, this oligopeptide stimulated the production of raw starch-digesting glucoamylase by immobilized fungal mycelia but did not stimulate the production of other proteins.

False aneurysms after aortic operations.

Between 1980 and August 1991, we encountered 11 non-infected aortic pseudoaneurysms after aortic surgery. The interval between the initial operation and revision varied from 1.8 to 26.8 years (mean 15.2 years). Three were found more than 20 years after operation. Pulling off of and degrading of the silk sutures were considered to be the causes. All patients underwent operative correction without mortality. In thoracic aortic pseudoaneurysm repair, a temporary bypass between the right axillary artery and left external iliac artery was generally adopted. There was no need for heparinization with this technique.

Operative management of abdominal aortic aneurysm with left-sided inferior vena cava.

Abdominal aortic aneurysm with left-sided inferior vena cava (IVC) is rare. In preoperative examination, it is important to conduct roentgenologic studies and determine any venous anomalies. Proximal anastomosis is technically difficult because the IVC crosses to the right on the aneurysmal neck. In this case of a 71-year-old Japanese man, proximal anastomosis was conducted safely under wide vena cava mobilization and contraction in the superior direction. In vein resection, vessels should be reconstructed because vein communication is not methodical.

Esmarch's bandage technique in distal bypass surgery.

Esmarch's rubber bandage technique has been applied to 49 distal bypass surgeries in 46 patients during the past ten years. The primary and secondary patency rates at 5 years after femoro-tibial bypass surgery were 82% and 92%, respectively. This technique has the following advantages: (1) it minimizes surgical injury of the arterial wall because there is less dissection around the anastomotic site; (2) it decreases scar formation in the anastomotic area after surgery; (3) it maintains abundant muscular blood flow by preserving small branches to muscles, and (4) it provides a bloodless surgical field and easy handling for fine sutures without using vascular clamps. We consider that the avoidance of long circumferential dissection of the artery may play an important role in improving long-term patency in distal bypass surgery.