Superior Mesenteric Artery Stent-graft Placement in a Patient with Pseudoaneurysm Developing from a Pancreatic Pseudocyst

Pseudoaneurysm is a relatively rare but serious complication of pancreatitis which is often fatal. We report successful stent-graft placement in the superior mesenteric artery in a 45-year-old man with a pancreatic pseudocyst that grew during therapy for chronic pancreatitis and developed into a pseudoaneurysm. After a stent graft was inserted in the superior mesenteric artery, the pseudoaneurysm disappeared and no further complications developed. Stentgraft placement was considered to be a useful therapy for pseudoaneurysms in the superior mesenteric arterial region.

Embolization of Collateral Vessels Using Mechanically Detachable Coils in Young Children with Congenital Heart Disease

Our objective was to evaluate the usefulness of embolizing collateral vessels using mechanically detachable coils (MDCs) in children aged 3 years or younger with congenital heart disease. The subjects were 8 children with congenital heart disease featuring collateral vessels (age 18 days-3 years): 3 with a single ventricle, 2 with the tetralogy of Fallot, 2 with pulmonary atresia, and 1 with a ventricular septal defect. The embolized vessels were the major aortopulmonary collateral artery (MAPCA) in 5 patients, the persistent left superior vena cava in 2, and the coronary arteriovenous fistula in 1. A 4 or a 5 F catheter was used as the guiding device, and embolization was performed using MDCs and other conventional coils introduced through the microcatheter. One patient had growth of new MAPCAs after embolization, and these MAPCAs were also embolized with MDCs. Thus, a total of 9 embolization procedures were performed in 8 patients. Complete occlusion of the collateral vessels was achieved in 8 of 9 procedures (89%). Seven of 8 patients (88%) had uneventful courses after embolization, and MDC procedures appeared to play important roles in avoiding coil migration and achievement of safe coil embolization. One patient who underwent MAPCA embolization showed no improvement in heart function and died 2 months and 19 days later. Embolization of collateral vessels using MDCs in young children with congenital heart disease can be an effective procedure and a valuable adjunct to surgical management.

SulA-independent filamentation of Escherichia coli during growth after release from high hydrostatic pressure treatment

To improve the efficiency of sterilization by high hydrostatic pressure treatment (HPT), it is desirable to know the biochemical process of bacteria most sensitive to the treatment. We investigated growth properties after release from HPT of exponentially growing Escherichia coli K-12 cells. We observed growth retardation after treatment (30 min at 37 degrees C) above 75 MPa. Long filamentous cells of about eight times normal cell length were observed at 90 min growth after treatment at 75 MPa. In the subsequent period the filamentous cells divided into normal-sized cells. recA and sulA mutant strains also formed filamentous cells, indicating that filamentation was SulA-independent. Nucleoids segregated normally in the filamentous cells. Only one FtsZ ring (or none) was detected at possible division sites in the elongated cells. Western blotting analysis demonstrated that the amount of FtsZ protein was not affected by the treatment. GTP-dependent in vitro polymerization of either FtsZ protein in E. coli crude extract or purified FtsZ protein, however, was sensitive to HPT. These facts suggest that HPT at 75 MPa denatures a fraction of FtsZ molecules, and that these denatured molecules interfere with the polymerization of functional FtsZ, resulting in the significantly reduced number of FtsZ rings.

Adenofibroma of the endometrium after tamoxifen therapy for breast cancer: MR findings

We report a case of adenofibroma of the endometrium in a 69-year-old woman. This patient was receiving tamoxifen therapy after surgery for breast cancer. Magnetic resonance imaging showed an intracavitary mass containing multiple cystic components. We suggest adenofibroma as a possible diagnosis in cases of uterine masses with multiple cystic components and no clinical evidence of malignancy.

[Aortic dissection in pregnant woman with the Marfan syndrome]

In patients with Marfan syndrome, pregnancy is associated with a potential higher risk of aortic dissection. To determine the incidence and characteristics of aortic dissection in pregnancy, clinical courses of 8 patients with Marfan syndrome were reviewed. Aortic dissection occurred in 3 patients, one of whom had developed rapid dilatation of the ascending aorta during pregnancy. The patient underwent Bentall operation subsequent to cesarean section and simple hysterectomy. All patients tolerated pregnancy well, with favorable maternal and fetal outcomes. Follow-up echocardiography showed no apparent worsening of cardiovascular status attributable to pregnancy such as aortic dilatation and aortic regurgitation except for one patient. Dilatation of the ascending aorta during pregnancy is considered to be an important predictor for aortic dissection. Close observation should be mandatory in such patients. In patients with serious cardiovascular involvement such as acute aortic dissection, cesarean section is preferable for delivery. To prevent hemorrhagic complications under systemic heparinization, simultaneous hysterectomy should be considered as one option.

[Aortic valve-sparing root reconstruction in Marfan syndrome]

The outcome of aortic valve-sparing root reconstruction in Marfan syndrome was reviewed. Thirteen patients with Marfan syndrome underwent aortic valve-sparing root reconstruction for annuloaortic ectasia or aortic root dissection between 1994 and 1999. The grade of preoperative aortic regurgitation was I in 4, II in 2, III in 5, IV in 2 patients. The procedures of aortic valve-sparing were reimplantation in 7 and remodeling in 5 patients. There was no hospital and late death. Recurrence of aortic regurgitation greater than moderate grade developed in 1 patient immediately after the surgery and in the other 4 patients in the late stage. One patient of them required aortic valve replacement for it. Aortic valve-sparing root reconstruction is applicable in Marfan patients, although the indication should be cautious. Close observation is needed for recurrence of aortic regurgitation.

[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.

A recurrent large Alu-mediated deletion in the hypoxanthine phosphoribosyltransferase (HPRT1) gene associated with Lesch-Nyhan syndrome

We identified the identical large genomic deletion in the hypoxanthine phosphoribosyltransferase (HPRT1) gene in two Japanese patients with Lesch-Nyhan (LN) syndrome. This deletion spanned from an Alu sequence in the promoter region to another Alu-sequence in intron 1, a length of 2,969 base pairs including exon 1. In order to ask whether this deletion was a recurrent mutation, we developed a simple alternative method to determine the separate origin of the HPRT1 mutation of the patients as assessed with an apparent mtDNA polymorphism. Considering that an LN syndrome-causing mutation is not transmitted from patient to offspring as LN syndrome is a fatal disease in childhood and that mtDNA is maternally inherited, HPRT1 mutations and mtDNA would be co-transmitted from carrier mother to offspring since both appeared in females. Two bases were different in the hypervariable region I of the mtDNA between the two patients, indicating the separate origin of their mtDNA over at least several thousand years as calculated based on the molecular evolution rate in this region. We thus conclude that the identical deletion found in HPRT1 of the two patients was derived from recurrent events of genomic recombination. Given that the same Alu-mediated deletion of HPRT1 has not been reported among somatic mutations at the same locus, this region of the HPRT1 gene flanked by Alu-sequences is likely a mutational hot spot in the germline but not in somatic cells. In addition, we also report novel LN-syndrome-conferring mutations in intron 6 (IVS6+1G --> C) and intron 8 (IVS7-9T --> G) that resulted in exclusions of exon 6 and exon 8, respectively.

CT-pathologic correlation in a case of solitary plasmacytoma of the rib

We report a case of solitary plasmacytoma of rib origin in a 46-year-old man. CT revealed a focal expanding mass in the right fifth rib. The mass showed ridging, cortical thickening, and fine erosion on the inner aspect of the cortex and had partly penetrated the bone. On both T1- and T2-weighted MR images, the mass showed low to intermediate intensity, and contrast studies showed homogeneous enhancement. Whole body bone scintigraphy revealed abnormal solitary accumulation, and therefore surgical resection was performed. Macroscopically the specimen revealed destruction of the cortex caused by tumor invasion, corresponding to the CT findings. Microscopic findings included a large number of plasma cells, leading to a histopathological diagnosis of plasmacytoma.

Pulmonary venous obstruction requiring lobectomy for hemoptysis after a Glenn operation

Right atrial isomerism is well known to be associated with anomalous pulmonary venous drainage and a potentially dangerous sequel to pulmonary venous obstruction, and is associated with high mortality. We report a 16-month-old girl with pulmonary venous obstruction requiring lobectomy for hemoptysis after a Glenn operation. Two years after surgery, she is doing well with 80% oxygen saturation and no further episodes of hemoptysis.

Ruptured left ventricular pseudoaneurysm penetrating into the left pleural cavity

We experienced a rare case of ruptured left ventricular pseudoaneurysm penetrating into the left pleural cavity. A 77-year-old woman was first diagnosed with unstable angina due to sudden chest pain onset and abnormal electrocardiographic findings. In 2 days, massive left pleural effusion was recognized by chest X-ray, though subsequent computed tomographic scans did not show any aortic pathology. We observed her with left thoracentesis alone. Two days later, cardiac arrest suddenly occurred and emergency surgery was undertaken after resuscitation by percutaneous cardiopulmonary support. In surgery, a moderate amount of intrapericardial hematoma caused by rupture of a left ventricular pseudoaneurysm penetrating into the left pleural cavity was found and successfully repaired. This rare rupture of a left ventricular pseudoaneurysm penetrating into the left pleural cavity generated massive hemo-hydrothorax.

Early and late results of partial plication annuloplasty for congenital mitral insufficiency

BACKGROUND

Partial plication annuloplasty is the main technique for congenital mitral insufficiency because this technique allows the mitral anulus to grow, in contrast to ring annuloplasty. However, this technique is not satisfactory for mitral insufficiency with some anomalies of the mitral valve apparatus.

METHODS

Forty-one patients underwent partial plication annuloplasty for mitral regurgitation from July 1979 to December 1998. Mitral regurgitation associated with an atrioventricular defect, an atrioventricular discordance, and a univentricular heart was excluded from this study.

RESULTS

There were no early or late deaths. In early results, partial plication annuloplasty was more effective for mitral regurgitation with abnormality of the posterior leaflet (n = 14) or normal leaflet motion (n = 8) than with abnormality of the anterior leaflet and its apparatus (n = 14) or absence of chordae (n = 4). The mean follow-up period was 145.8 months. During the follow-up period, 2 patients underwent mitral valve replacement, and a third patient underwent mitral valve repair with partial plication annuloplasty after the first repair. The main cause of mitral regurgitation of 2 of the 3 patients was absence of chordae. The actuarial freedom from reoperation rate was 94.9% +/- 3.6%, 91.9% +/- 4.7%, and 91.9% +/- 4.7% at 5, 10, and 15 years after the operation, respectively.

CONCLUSION

Early and long-term results of partial plication annuloplasty were acceptable for congenital mitral insufficiency with any type of malformation of the mitral valve, and results were excellent with abnormality of the posterior leaflet and its apparatus or normal leaflet motion. However, late results were suboptimal for mitral regurgitation with absence of chordae. Other techniques, such as artificial chorda replacement, should be adapted in these cases.

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.

Coronary artery bypass grafting for patients with an atherosclerotic ascending aorta

OBJECTIVES

We review the outcome of coronary artery bypass grafting in patients with a severe atherosclerotic ascending aorta.

METHODS

Subjects were 31 patients averaging 69.4 +/- 6.9 years old studied from 1990 through 1998. Ascending aortic lesions were assessed using epiaortic echo and 2 types of aortic nonclamping techniques applied. In 29 patients operated on in the early years, bypass grafting was conducted on the hypothermic fibrillated heart in 22 and on the beating heart in 7. The remaining 2 underwent off-pump coronary artery bypass grafting more recently. For cases with multivessel disease, we used composite grafting.

RESULTS

Three patients developed mild stroke and 5 died within 30 days of surgery--4 from multiple emboli (1 accompanied by a stroke) and 1 from perioperative myocardial infarction. One hospital death occurred due to brain damage and multiorgan failure following unexpected rupture of a saphenous vein graft. No cardiac deaths occurred in the late stage of our series. Actuarial survival was 73.0% for 3 years and 68.0% for 5 years. Freedom from cardiac events was favorable in the remaining 25 survivors.

CONCLUSIONS

Outcome was suboptimal for the risks involved. Recent technical advances, including coronary surgery on the beating heart with or without cardiopulmonary bypass using variable in-situ or free arterial grafts, associated with adequate evaluation of systemic atherosclerosis, should improve this outcome.

Surgery for acute type A aortic dissection using retrograde cerebral perfusion

OBJECTIVE

We reviewed the surgical management of acute type A aortic dissection between 1989 and 1998.

METHODS

Subjects were 28 consecutive patients (mean age: 61.8 +/- 10.7 years) with acute type A aortic dissection were studied. The mean duration between aortic dissection onset and surgery was 17.5 +/- 17.0 hours. In surgery, aortic pathology and flow patterns in dissected aortic channels were evaluated using transesophageal and epiaortic echo. Simple, safe combination of profound hypothermic circulatory arrest with retrograde cerebral perfusion and open aortic anastomosis was used for brain protection. Hypothermic circulatory arrest was 46.9 +/- 24.8 minutes. Aortic repair consisted in ascending aortic replacement in 5 patients, with hemiarch repair in 17, and total arch repair in 6. Intimal tears were resected in all but 2 patients. Concomitantly resuspension of the aortic valve was done in 9 and aortic root replacement in 2.

RESULTS

No operative (30-day) deaths occurred, although 2 died from unrelated hepatic failure during hospitalization or late-stage pancreatic cancer in the late stage. In cerebral sequellae, 1 patient suffered a stroke and 2 patients developed temporary neurologic dysfunction.

CONCLUSION

Our experience demonstrated that the simplified conjunction of hypothermic circulatory arrest with retrograde cerebral perfusion and open aortic anastomosis, associated with real-time assessment by transesophageal and epiaortic echo, is safe and useful during emergency aortic repair for acute type A aortic dissection.

5-Bromodeoxyuridine suppresses position effect variegation of transgenes in HeLa cells

An ectopic gene integrated in the host genome is occasionally silenced due to a position effect of its adjacent chromatin structure. We found that 5-bromodeoxyuridine clearly activated such a transgene in HeLa cells. The transgene was also activated to various degrees by inhibitors of histone deacetylase, DNA topoisomerases, or DNA methyltransferase. The peptide antibiotic distamycin A potentiated markedly the effect of 5-bromodeoxyuridine. Transient expression of an artificial AT-hook protein termed MATH20 also potentiated its effect although significantly activated the transgene alone. Since distamycin A and MATH20 are able to displace histone H1 and other DNA-binding proteins bound to specific AT-rich sequences by a dominant, mutually exclusive fashion, these results suggest that 5-bromodeoxyuridine targets such an AT-rich sequence located adjacent to the silenced transgene, resulting in chromatin accessibility.

A case of isolated esophageal cyst in the posterior mediastinum

We report a rare case of posterior mediastinal esophageal cyst associated with pulmonary anomaly that had no connection with the proper esophagus, on either CT or MRI, and suggest including this entity in the differential diagnosis of posterior mediastinal masses.

[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.

[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.

Induction of senescence-associated genes by 5-bromodeoxyuridine in HeLa cells

5-Bromodeoxyuridine (BrdU) universally induces a senescence-like phenomenon in mammalian cells. To assess this phenomenon at the level of gene expression, we constructed a PCR-based subtractive cDNA library enriched for mRNA species that immediately increase by administration of BrdU to HeLa cells. Candidate cDNA clones were isolated by differential colony hybridization, and then positive clones were identified by Northern blot analysis. Sequencing analysis revealed that the identified cDNA species were classified into three groups: widely used senescence-markers, known species whose relevance to senescence is yet to be reported, and known or novel ESTs. As expected, the majority of them showed an increase in expression in senescent human diploid fibroblasts. These results suggest that similar mechanisms operate in the regulation of BrdU-induced genes and senescence-associated genes.

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.

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.

Aortic arch repairs through three different approaches

OBJECTIVES

The outcome of aortic arch repairs by means of three different approaches between 1990 and January 2000 was reviewed.

METHODS

In total 39 patients aged 71.5+/-6.2 years were operated on. The three different surgical approaches depended on the anatomical positions of the aneurysms and on their proximal or distal extension; a median approach was employed in 23 patients, whereas a left postero-lateral approach was used in eight patients. More recently, in eight cases a left antero-lateral approach was applied. All patients underwent open aortic anastomosis without any clamp on or around the aortic arch. During the procedure, the brain was protected by a combination of profound hypothermic circulatory arrest and several techniques of retrograde cerebral perfusion.

RESULTS

Permanent cerebral dysfunction occurred in four patients: two in the median approach and two in the left postero-lateral approach. There were two hospital deaths (5.3%) and six late deaths, all of which belonged either to the median group or to the postero-lateral group. The antero-lateral approach did not produce any cerebral dysfunction, early death, or late death.

CONCLUSIONS

The outcome of aortic arch repairs using profound hypothermic circulatory arrest and variable techniques of retrograde cerebral perfusion, by means of three different approaches, was satisfactory. Of the three approaches, the antero-lateral approach can be employed easily, whether aneurysms extend proximally or distally.

A case of right-sided aortic arch with isolation of the left subclavian artery: CT findings

We report a case of right-sided aortic arch with isolation of the left subclavian artery diagnosed using computed tomography (CT). This was a rare type in which the left subclavian artery, originating from the pulmonary artery via the arterial duct, was isolated after closure of the ductus. Collateral circulation was considered to be obtained mainly from the left intercostal artery via the costocervical trunk through the supreme intercostal artery.

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.

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.

[Long-term results of right ventricular outflow reconstruction with valved conduit]

Twenty-nine patients who underwent right ventricular outflow tract reconstruction using a valved conduit 37 times and survived surgery, were reviewed in this study. Hancock, Ionescu-Shiley, Carpentier-Edwards and Polystan was used for RVOTR. Freedom from reoperation rates of Hancock, Ionescu-Shiley and Carpentier-Edwardsat at five and ten years after surgery were 100%, 85.7%, 89.2% and 75%, 28.6%, 89.2%, respectively. The freedom from reoperation rates of Hancock and Carpentier-Edwards were significantly higher than that of Ionescu-Shiley. In conclusion, the freedom from reoperation rate at ten years was high for both Hancock and Carpentier-Edwards.

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.

Apoptosis, cell proliferation and expression of oncogenes in gastric carcinomas induced by preoperative administration of 5-fluorouracil

The purpose of this study was to examine the correlations among enhancement of apoptosis, cell proliferation and expression of oncogenes in gastric carcinomas induced by preoperative oral administration of 5-fluorouracil (5-FU). The occurrence of spontaneous apoptotic cell death in 42 patients with gastric carcinoma was analyzed in the biopsy specimens preoperatively. p53 status was examined by polymerase chain reaction-single strand confirmation polymorphism and sequencing. Fourteen patients received oral administration of 5-FU at 300 mg/body/day for 7 days preoperatively. For detection of apoptotic cells, apoptotic incidences (AIs) were examined by the terminal deoxynucleotidyl transferase-mediated deoxy-uridine triphosphate biotin nick end labeling method, on gastric carcinoma lesions based on the endoscopic findings before administration in the biopsy and resected tissues. Expressions of p53, Bcl-2, Bax gene and proliferating cell nuclear antigen (PCNA) were also examined by immunohistochemical staining. On preoperative biopsy, p53 point mutation was observed in 14 of the 42 tumors. The immunohistochemical staining status and point mutation of p53 gene (positive or negative) were identical in 32 of the 42 tumors (76.2%). The average AIs of the biopsy specimens were 1.58+/-1.26% on p53-negative staining (n=19) and 1.14+/-1.02% on p53-positive staining (n=23), a significant association was not recognized between p53 expression and AI. In the preoperative administration group, the PCNA labeling index was significantly higher in the biopsy specimens than in the resected tissues (43. 6+/-12.8% vs. 35.3+/-8.8%, p<0.01). In addition, postoperatively, the rate of AI was significantly more accelerated in p53-negative staining (n=6) than in p53-positive staining (n=8) (0.89+/-0. 65%right curved arrow 4.18+/-3.26%, p<0.05 vs. 1.20+/-0.60%right curved arrow 2.60+/-2.60%, NS). There was no significant correlation between AI and Bcl-2 or Bax staining. Immunohistochemical analysis of p53 and PCNA stainings in biopsy specimens appears to be a well-characterized indicator of sensitivity of chemotherapy in gastric carcinomas.

[Long-term effect of polystan monocusp ventricular outflow patch after right ventricular outflow tract reconstruction]

Forty-eight patients who underwent right ventricular outflow tract reconstruction with Monocusp Ventricular Outflow Patch (MVOP) fifty-five times and survived surgery, were reviewed in this study. Mean age at surgery was 6.4 years-old and mean follow-up interval was 75.2 months. There was no late death, however reoperation was performed 7 times. Freedom from reoperation rate was 97.2% and 80.7% after 5 and 10 years after surgery, respectively. The main cause for reoperation were right ventricular outflow obstruction RVOTO (5 cases). All of the RVOTO occurred at the distal end of the anastomosis. However, there was no RVOTO in patients who underwent RVOTR with MVOP during the past ten years. So, we considered the cause of RVOTO a technical problem. Pulmonary regurgitation was one to two degree early after surgery, and had worsened by almost two or three degrees more than 5 years after surgery. Moreover, five of six patients who underwent cardiac catheterization more than 10 years after surgery had three degrees of pulmonary regurgitation as well as a large CTR. In conclusion, according to long-term results, especially more than 10 years post operatively, pulmonary regurgitation was the most important problem.

A case of thymic cyst associated with thymoma and intracystic dissemination

We report a rare case of anterior mediastinal thymic cyst together with a thymoma and its intracystic dissemination. More attention should be given to intramural nodules, especially in patients with an anterior mediastinal thin wall cystic lesion.

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.

[Surgical results of the Senning operation and arterial switch operation for complete transposition of the great arteries]

From March 1980 to August 1997, 42 patients with complete transposition of the great arteries (TGA) type I and II underwent arterial switch procedure (n = 20) or Senning (n = 22) procedure in our institution. In arterial switch procedure group, there were two operative death. No late death occurred, and one patient underwent reoperation and one underwent balloon pulmonary angioplasty for right sided obstruction. The freedom from the intervention rate for right sided obstruction was 83.0% at 5 years, subsequently. In Senning procedure group, operative death occurred in two patients with TGA type II, and one patient with TGA type II and two patients with type I died because of cardiac events in the late stage. In this group, two patients died from accident. The survival rate excluding accidental deaths was 77.7% and 77.7% at 5 and 10 years, respectively. However, those patients who died in the late stage had severe pre-operative and post-operative complication. In conclusion, mid-term results of arterial switch procedure is satisfactory, however, reintervention rate was not so low. Long term results of Senning procedure without preoperative or postoperative complication was satisfactory.

Toxicologic evaluation of yessotoxin

Yessotoxin (YTX), originally found in association with diarrhetic shellfish poisoning (DSP), caused neither intestinal fluid accumulation nor inhibition of protein phosphatase 2A. Orally, YTX was not lethal to mice at 1.0 mg/kg. The toxin showed weak cytotoxic and antifungal activities. Neither hemolytic nor ichthyotoxic effect was observed.

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.

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.

Treatment for abdominal aortic graft infection: irrigation with electrolyzed strong aqueous acid, in-situ grafting, and omentoplasty

We report on successful surgical treatment of consecutive three patients with infection of an abdominal aortic graft, Therapy involved a combination of removal of the infected graft, elaborate debridement, irrigation with electrolyzed strongly acidic aqueous solution (ESAAS), in-situ regrafting, and omentoplasty. The use of ESAAS is discussed.

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.

[Development of DICOM image browser for Macintosh computer]

Although many medical image browsers are available today, most are extremely expensive. To solve this problem, we developed a Digital Imaging and Communications in Medicine (DICOM) image browser (Medical Image Browser) for Macintosh computers. A comparison between this software, Advantage Workstation, NIH Image, and Graphic Converter suggested that this software is useful for diagnosis on the Macintosh desktop. This software is available at wwwl.odn.ne.jp/cak42860.

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.

Oral administration of the dopamine prodrug docarpamine shortens need for drip infusion of dopamine in patients with low cardiac output syndrome after cardiac surgery

BACKGROUND

Docarpamine (DOC) is a dopamine prodrug which can be orally administered. It has been found that oral docarpamine transforms into dopamine in vivo, and increases cardiac output and renal blood flow as effectively as intravenous dopamine.

METHODS

We reviewed the records of 26 patients who had developed low cardiac output syndrome (LOS) after cardiac surgery and received docarpamine during the early postoperative course. Five patients discontinued docarpamine within 2 days due to arrhythmia. There were 3 hospital deaths. The remaining 18 patients were divided into two groups according to the timing of docarpamine administration. In group A docarpamine was administered during and after weaning from intravenous catecholamines, in group B only on demand after weaning from intravenous catecholamines.

RESULTS

There were 12 patients in group A and 6 in group B, and the severity of LOS was relatively milder in group B than in group A. Stable hemodynamics and sufficient daily urinary output were maintained by oral administration of DOC in both groups just as well as by drip infusion of catecholamines.

CONCLUSION

Sinse continuous drip infusion of catecholamine commonly slows recovery in LOS patients, it is considered that switching from drip infusion of catecholamines to oral DOC administration is safe and useful for earlier recovery in LOS patients after cardiac surgery.

Purulent pericarditis presenting as an extracardiac mass in a patient with untreated diabetes

A 50-year-old man with symptoms of bi-ventricular heart failure was transferred to our hospital with a diagnosis of extracardiac tumor. He had a 10 year history of untreated diabetes. Chest computed tomography (CT) revealed an extracardiac mass in the right atrio-ventricular groove. Cardiac catheterization revealed an elevated mean right atrial pressure of 18 mmHg, mean pulmonary wedge pressure of 16 mmHg, and the right ventricular pressure curve demonstrated typical dips and plateaus. At surgery, there was severe adhesion between the pericardium and epicardium, and the pericardium was severely thickened and contained turbid pus. In the left thoracic cavity, there was large amount of pleural effusion and pus. Therefore, the patient was diagnosed with purulent pericarditis caused by left empyema. The thickened pericardium at the anterior portion of the heart was resected, however resection of the remaining portion was abandoned because the adhesion was so tight. After surgery, the patient underwent irrigation of the heart and left thoracic cavity by 1% povidone iodine solution and 0.5 mg/ml of imipenem for 7 days. Bacteriologic culture of the pus from the pericardium revealed anaerobic gram negative bacteria. After 4 months of antibiotics infusion, his C reactive protein became negative and the patient was subsequently discharged from our hospital.

Combined cardiac surgery and total thyroidectomy: a case report

A 65-year-old woman with aortic stenosis, ischemic heart disease, and Graves' disease had complained of effort angina. She then suffered from liver dysfunction due to treatment with antithyroid drugs. One year after the start of radioiodine administration, she demonstrated unstable angina with palpitation and sweating. Laboratory studies revealed a recurrent hyperthyroid state, and a second coronary angiogram revealed progressive ischemic heart disease. Combined coronary artery bypass grafting, aortic valve replacement, and total thyroidectomy were performed. The postoperative course was uneventful without any problems associated with hyperthyroidism or hypothyroidism. Combined cardiac surgery and total thyroidectomy can be performed safely if the perioperative levels of thyroid hormone are maintained at euthyroid or hypothyroid levels.

5-Bromodeoxyuridine induces senescence-like phenomena in mammalian cells regardless of cell type or species

5-Bromodeoxyuridine was found to induce flat and enlarged cell shape, characteristics of senescent cells, and senescence-associated beta-galactosidase in mammalian cells regardless of cell type or species. In immortal human cells, fibronectin, collagenase I, and p21(wafl/sdi-1) mRNAs were immediately and very strongly induced, and the mortality marker mortalin changed to the mortal type from the immortal type. Human cell lines lacking functional p21(wafl/sdi-1), p16(ink4a), or p53 behaved similarly. The protein levels of p16(ink4a) and p53 did not change uniformly, while the level of p21(wafl/sdi-1) was increased by varying degrees in positive cell lines. Telomerase activity was suppressed in positive cell lines, but accelerated telomere shortening was not observed in tumor cell lines. These results suggest that 5-bromodeoxyuridine activates a common senescence pathway present in both mortal and immortal mammalian cells.

Introduction of chromosome 7 suppresses telomerase with shortening of telomeres in a human mesothelial cell line

Introduction of human chromosome 7 by microcell-mediated chromosome transfer induced senescence in a telomerase-positive human mesothelial cell line, MeT5A. In microcell hybrids which underwent senescence, telomerase activity was decreased before entering senescence and telomeric sequences were shortened as cell division proceeded. Concomitantly, expression of the gene encoding telomerase catalytic subunit was abolished, whereas the genes encoding the RNA component of telomerase and its associated protein TEP1 were not affected. In revertants which arose from such microcell hybrids, telomerase activity was restored and the telomeric sequences were elongated. In microcell hybrids which showed no growth arrest, telomerase activity was unaltered. These results suggest that a putative mortality gene on chromosome 7 negatively regulates the telomere maintenance mechanism in MeT5A.

Chronic aortic dissection (DeBakey type II) with infective thrombus in the false channel

A 68-year-old man with a DeBakey type II chronic aortic dissection developed bacteremia secondary to a urinary tract infection with the Serratia species. This resulted in an infected thrombus in the false channel and a subsequent rupture of the ascending aorta. An emergency resection of the ascending aorta and a Dacron graft interposition were performed. The patient suffered from severe neurological insufficiency and died of pneumonia 6 months postoperatively. The optimal operation time and surgical options of an infected aortic dissection should be determined.

Distance between mitral anulus and papillary muscles: anatomic study in normal human hearts

BACKGROUND

Preservation of the annulo-papillary muscle continuity in mitral valve replacement is important. Even in patients who require excision of the mitral apparatus, the continuity can be restored. However, there is no guide to the proper length for the resuspension.

METHODS

In 57 normal cadaveric hearts, the distance from the tip of the papillary muscle to its corresponding mitral anulus was directly measured.

RESULTS

The distance from the tip of the anterolateral papillary muscle to the left trigone (10-o'clock position: D10) and to the point between the anterior and the middle scallops of the mural leaflet (8-o'clock position: D8) was 23.5 +/- 3.7 mm and 23.2 +/- 3.6 mm, respectively. The distance from the tip of the posteromedial papillary muscle to the right trigone (2-o'clock position: D2) and to the point between the middle and the posterior scallops of the mural leaflet (4-o'clock position: D4) was 23.5 +/- 4.0 mm and 23.5 +/- 3.9 mm, respectively. There was no statistically significant difference among the 4 distances (P =.96). Each distance was significantly longer than the corresponding chordae tendineae (D10 vs the anterior main chorda: 17.2 +/- 3.9 mm, D8 vs the anterior cleft chorda: 14.5 +/- 3.2 mm, D2 vs the posterior main chorda: 17.9 +/- 4.3 mm, and D4 vs the posterior cleft chorda: 14.9 +/- 3.2 mm, respectively; P =.0001). The mean distance had a significant correlation with the mitral annular diameter (r = 0.31, P =.019).

CONCLUSIONS

In normal hearts, the annulo-papillary muscle distances of the mitral apparatus are similar in 2-, 4-, 8-, and 10-o'clock positions and correlate with the mitral annular diameter.

Aortic valve replacement for aortic regurgitation in a patient with primary antiphospholipid syndrome

A 42-year-old woman with the diagnosis of aortic regurgitation was admitted to hospital for surgical treatment. Ten years ago, primary antiphospholipid syndrome had been diagnosed, and she had a history of recurrent spontaneous abortions and deep vein thrombosis. She was suffering from moderate exertional dyspnea and chest pain. Catheter investigation revealed progressive dilatation of the left ventricle and a deterioration of the ejection fraction. The aortic valve was excised and replaced with a mechanical valve. A specimen of the aortic valve showed localized thickening and shrinkage of the midportion and base of each cusp, with vegetation on the surface. These localized, specific findings suggest that another mechanism may be involved in the cardiac valve pathology in patients with primary antiphospholipid syndrome. No hemostatic or thromboembolic problems were encountered after the surgery, and her postoperative course was uneventful.

Regulation of lens fiber cell differentiation by transcription factor c-Maf

To elucidate the regulatory mechanisms underlying lens development, we searched for members of the large Maf family, which are expressed in the mouse lens, and found three, c-Maf, MafB, and Nrl. Of these, the earliest factor expressed in the lens was c-Maf. The expression of c-Maf was most prominent in lens fiber cells and persisted throughout lens development. To examine the functional contribution of c-Maf to lens development, we isolated genomic clones encompassing the murine c-maf gene and carried out its targeted disruption. Insertion of the beta-galactosidase (lacZ) gene into the c-maf locus allowed visualization of c-Maf accumulation in heterozygous mutant mice by staining for LacZ activity. Homozygous mutant embryos and newborns lacked normal lenses. Histological examination of these mice revealed defective differentiation of lens fiber cells. The expression of crystallin genes was severely impaired in the c-maf-null mutant mouse lens. These results demonstrate that c-Maf is an indispensable regulator of lens differentiation during murine development.