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We describe a 69-year-old woman with primary lung cancer in the right lower lobe invasive to the left atrium (LA) via the pulmonary vein (PV). The tumor in the LA measured 30 × 26 mm, and to avoid critical embolism preoperative induction therapy was not performed. The patient underwent right thoracotomy under cardiopulmonary bypass (CPB), and the atrial septum was incised via the right atrium. The tumor was placed out of the LA, followed by lobectomy. For right lung tumors invading the LA, the bilateral trans-septal approach is useful for confirming the surgical margin.

In recent years, re-rupture due to endoleaks after thoracic endovascular aortic repair (TEVAR) for ruptured thoracic aortic aneurysms has become a problem. Hemoptysis has been reported in patients after pneumocentesis. We report a patient who developed delayed hemoptysis not related to endoleak after TEVAR. An 80-year-old male underwent emergent TEVAR due to a ruptured thoracic aortic aneurysm accompanying sudden hemoptysis. Eleven days after the operation, recurrent hemoptysis was noted, but contrast-enhanced computed tomography (CT) revealed no endoleak or re-rupture. Bronchoscopy demonstrated hemorrhage from the left upper lobe. As hemostasis was difficult by conservative treatment, left upper lobectomy was performed. The aortic rupture hole exhibited thrombus, and there was no hemorrhage. On histopathological examination of the resected lung, formation accompanied by severe intra-alveolar fibrosis and cholesterin clefts, and marked foreign body reactions in the interstitium and small blood vessels of the lung were observed. Cholesterol embolism is associated with not only organ ischemia due to microembolism, but also immunological mechanisms. Thus, cholesterol embolism due to aorta-derived cholesterin may have led to the delayed pulmonary hemorrhage. Differentiation from re-rupture due to endoleaks is important.

This study was conducted to evaluate the biocompatibility of titanium-nickel shape memory alloy used as a medical implant material. The authors carried out the following electrochemical corrosion test and in vivo and in vitro biological tests for the alloy and some metal and alloys clinically used previously to compare the intensities concerned with the biological reactions, that is, (1) anodic polarization test for the alloy i na quasi-body fluid, (2) cell proliferation tests for pure titanium (cp Ti), pure nickel (cp Ni), SUS316L stainless steel, titanium-6 mass% aluminium4 mass% vanadium (Ti-6Al-4V), and titanium-55 mass% nickel (Ti-55Ni) by using of L929 fibroblastic cells, (3) Lactate dehydrogenaze (LDH), human interlukin-1� (hIL-1� ), and human tumor necrosis factor-� (hTNF-� ) biochemical assays by using of U937 human macrophages administered the corrosion products of these alloys for the cells, (4) measurement of the mount of excretions of the metallic corrosion products of Ti-55Ni, SUS316L stainless steel, and Ti-6Al-4V with urine and feces injected into the abdomen cavity of Wistar rats, and (5) tissue reaction observations for SUS316L, Ti-55Ni, and cp Ni wires implanted along the femoral bone axis of the rats. The following results were obtained. (1) The pitting corrosion potentials of Ti-55Ni alloy was drastically improved by the aging treatment. (2) In the case of Ti-55Ni alloy, the inflammatory cytokines, hIL-6� and hTNF-� were suppressed to lower levels compared with Ti-6Al-4V alloy. (3) Corrosion products prepared from the titanium alloys were stable in the body. Then it is very hard to eliminate the titanium ions with urine and feces. (4) Ti-55Ni alloy was shown an excellent biocompatibility evaluated by the in vivo implantation test, because of the stable passive film formed on the surface and protected the metal ion release to the surrounding tissue. [doi:10.2320/matertrans.48.352]

TiC/Ti and TiC/Ti-15Mo cermets were fabricated for the bearings of joint prostheses and were then evaluated in terms of their mechanical properties, such as density, hardness, bending strength and fracture toughness, as well as biocompatibility. The cermets were fabricated by spark plasma sintering. When the volume fraction of the metal phase was increased, the fracture toughness and the bending strength of the TiC/Ti and TiC/Ti-15Mo increased. The TiC/Ti and the TiC/Ti-15Mo cermets show high biocompatibility and corrosion resistance. These results indicate that TiC/Ti-15Mo cermets are suitable for use in the bearings of joint prostheses.

A 59-year-old male who had undergone mitral valve replacement with the Starr-Edwards ball valve Model 6120 (S-E ball valve) 45 years ago was admitted to our hospital for hemolytic anemia and heart failure. Echocardiography revealed that there was no valve dysfunction but paravalvular leakage between the annulus of P2 and the sewing ring of the Starr-Edwards ball valve. He underwent mitral valve replacement. The S-E ball valve was successfully replaced with bileaflet mechanical valve. The explanted S-E ball valve was free from signs of structural valve degeneration. This case shows one of the longest durability of the S-E ball valve in mitral position in the world.

Little is reported about primary cardiac osteosarcoma from mitral valve. We report a surgical case of primary cardiac osteosarcoma arising from mitral valve. The patient was a 54-year-old woman with congestive heart failure caused by mitral regurgitation due to a tumor (30 × 20 mm) from the posterior leaflet. We performed complete resection of the tumor combined with the mitral valve and replaced it to a mechanical valve. Histopathological examination showed evidence of complete excision of cardiac osteosarcoma. Sixteen months after the initial surgery, the mechanical valve has a trouble with its opening of leaflets due to local recurrence in the mitral annulus, and 2nd mitral valve replacement following tumor excision was performed. Eighteen months after the 2nd surgery, the patient finally died by recurrence as well as invasion of osteosarcoma from mitral annulus to left ventricular myocardium. We discussed about the management and treatments of primary cardiac osteosarcoma in this case.

The authors developed 3Y-PSZ/AISI 316L composites for the bearings of joint prostheses, which were then evaluated in terms of their mechanical properties, such as density, hardness, bending strength, fracture toughness and wear resistance, as well as corrosion resistance. The composites (AISI 316L contents were 0, 10, 20 and 30 vol%) were fabricated by spark plasma sintering. The composites consist of tetragonal zirconia and austenite stainless steel. The Vickers hardness and bi-axial bending strength of the composite decrease from 14.3 GPa to 8.93 GPa and 1585 MPa to 617 MPa, respectively, when the AISI 316L content is increased from 0 vol% to 30 vol%. Fracture toughness of the composite increased from 4.99 MPa.m 1 / 2 to 6.03 MPa.m 1 / 2 . The composites showed improved wear resistance (3Y-PSZ; 3.08 x 10 - 1 0 mm 2 /N, 10 vol% composite;2.11 x 10 - 1 0 mm 2 /N, 20 vol% composite; 0.28 x 10 - 1 0 mm 2 /N, 30 vol% composite; 0.00 x 10 - 1 0 mm 2 /N). The wear resistance of the 30 vol% composite was higher than conventional biometal and bioceramic (AISI 316L; 35.4 x 10 - 1 0 mm 2 /N, Co-28Cr-6Mo; 11.0 × 10 - 1 0 mm 2 /N, Al 2 O 3 ; 0.30 × 10 - 1 0 mm 2 /N). The composites showed more than 3 times greater corrosion resistance than the monolithic AISI 316L in PBS(-) at 37°C. In particular, nickel ion release was lower than for AISI 316L. The corrosion resistance of 30 vol% composite during the wear test was more than 37 times higher than for AISI 316L. The 30 vol% composite was successfully toughened and showed higher resistance to wear and corrosion when used as bearing material for joint prostheses.

The wear debris caused by joint prosthesis is well known to induce an inflammation in the peripheral tissue. The authors carried out two kinds of experiments, to clarify the phagocytable size of wear particles and the cytotoxicity of macrophage related to the size and materials. The test materials were Al2O3, SiO2, TiO2 fine particles and Ti-6Al-4V, Co-28Cr-6Mo wear particles. The results showed that the phagocytable particle size was less than 11.9±11.2µm. It appears that the cytotoxicity did not depend on the particle size, even if the particles were phagocytable size. In the relationship between material type and inflammation, damage levels were found to be different between SiO2 and TiO2 particles, even if neither material released metal ions. The cells were damaged more severely by SiO2 particles than by Co-28Cr-6Mo for which the eluted ion could not be ignored (damage levels; SiO2>Co-28Cr-6Mo>Ti-6Al-4V>Al2O3≧TiO2). For these reasons, it was confirmed that there was a factor in addition to the toxicity of the eluted metal ion (i. e., the implant material's corrosion resistance ability), which influenced the inflammation.

Pin on disk friction tests were carried out for three types of metals, 316L S.Steel, Co-28Cr-6Mo, and Ti-6Al-4V alloys in PBS(-) to estimate the range of loads that can be applied to the bearing surface of a joint prosthesis, based on the degree of damage to the passivation film. The results were as follows: (1) When two metals of the same type were rubbed against each other, the passivation film was almost completely destroyed immediately after the onset of friction, even when a very low normal load was applied. (2) In the metal to UHMWPE friction test, the passivation film was severely damaged immediately after the onset of friction. However, the passivation film recovered until the polarization potential reached a certain level, which was specific to each metal. (3) The allowable load on the bearing head was calculated, assuming that the degree of damage to the passivation film was 20% or 40%. When a metal acetabulum socket was used, damage to the passivation film on the head was severe, regardless of the type of metal used for both the acetabulum socket and the head. When a UHMWPE acetabulum socket was used, the allowable load ranged from 8.16x10 2 N to 1.31x10 5 N for 316L S.Steel, from 7.83x10 3 N to 1.31x10 5 N for Co-28Cr-6Mo alloy, and from 43N to 6.08x10 2 N for Ti-6Al-4 Valloy.

We reported a case of racemose hemangioma of the bronchial artery and intercostal to pulmonary arterial anastomosis. A 67-year-old woman was admitted because of repeated hemoptysis. Bronchoscopic examination revealed a torous lesion of the right B7 bronchus. Intercostal angiography demonstrated communications between right dilated, meandered intercostal arteries and right pulmonary artery. Bronchial angiography showed dilatation and convolution of the right bronchial artery. Angiographic embolization of the right bronchial artery and the right intercostal artery was underwent. There was no recurrence of hemoptysis one year after the embolization procedure. We think that angiographic embolization is an effective method of treatment of hemoptysis due to racemose hemangioma of the bronchial artery and intercostal to pulmonary arterial anastomosis.

A 61-year-old male had undergone coronary artery bypass grafting (CABG) using a saphenous vein. Postoperative angiography represented an ascending aortic pseudoaneurysm derived from the proximal anastomotic site of the saphenous vein graft( SVG) which was connected to the obtuse marginal branch and left posterior descending branch sequentially. We performed the closure of tear and the plication of pseudoaneurysmal wall through median sternotomy on the 56th postoperative day. A 7mm length longitudinal tear in the ascending aorta close to the proximal anastomotic site of the SVG was observed. This tear was considered to be caused by the intimal injury during the anastomosis of SVG to ascending aorta. Aortic pseudoaneurysm formation close to the proximal anastomotic site of SVG is a rare and potentially lethal complication requiring urgent operation. Postoperative angiography or enhanced 3 dimensional computed tomography after CABG should be performed before hospital discharge.

A 28-year-old man arrived at our hospital complaining of severe dyspnea. Bronchoscopic findings demonstrated that a tumor was located approximately 4 cm distant from the vocal cord, occupying most of the tracheal lumen. To urgently relieve the dyspnea, some parts of the tumor were cauterized with the neodymium:yttrium-aluminum garnet laser. Histopathologic examination of the cauterized specimen revealed malignant hemangiopericytoma. During the operation, the tumor was resected en bloc with a tracheal segment containing four tracheal cartilages. The patient's postoperative course was uneventful with no evidence of recurrence 1 year after the operation.

In their previous study, the authors carried out a fatigue test for AISI 316, 316L stainless steels and COP1 alloy in a living animal body and observed a remarkable deterioration in the fatigue durability of these metals. In that study, it was concluded that the reason the corrosion resistance of the metals was reduced in the living body was that the low concentration of dissolved oxygen gas in the body fluid (the partial pressure pO2; 28-78 mmHg) was insufficient to form the chromium oxide passivation film on the metal surface, and the base metal (iron) was released into the environmental fluid in ionic form. In this paper, with the concentration of dissolved oxygen gas in a physiological normal saline solution being set equivalent to that of living body fluid, fatigue tests on AISI 316 were made to simulate the stress corrosion behavior of the metal in the living body. As a result, remarkable deterioration of fatigue strength was observed in the low O2 concentrated normal saline solution, which was the same as that in the living animal body.

We report tensile, shearing, and bending tests on bone cement to which cefuzonam sodium (Cosmosin®), a third generation cephalosporin, had been mixed. Mixing 3 g of cefuzonam sodium to 40 g of polymethyl methacrylate (PMMA) polymer did not diminish the strength of the bone cement in any of the tests. We speculated that this lack of influence was because the cefuzonam sodium powder used was in the form of relatively uniform-sized spheres and therefore did not become the origin of stress concentration within the cement.

A chemical examination of the polyphenolic constituents of the fern, Dicranopteris pedata HOUTT., has led to the isolation of eight new proanthocyanidins possessing a doubly-linked (A-type) unit, together with known flavan-3-ols and proanthocyanidins. On the basis of chemical and spectroscopic evidence, they are characterized as epiafzelechin-(4β→8, 2β→O→7)-eniafzelechin-(4α→8)-epiafzelechin(8), epicatechin-(4β→8, 2β→O→7)-epiafzelechin-(4α→8)-epiafzelechin(9), epiafzelechin-(4β→8, 2β→O→7)-epizfzelechin-(4α→8)-epicatechin(10), epiafzelechin-(4β→8, 2β→O→7)-epicatechin-(4α→8)-epicatechin (11), epicatechin-(4β→8, 2β→O→7)-epiafzelechin-(4α→8)-epicatechin (12), epicatechin-(4β→8, 2β→O→7)-epicatechin-(4α→8)-epiafzelechin (13), epicatechin-(4β→8, 2β→O→7)-epicatechin-(4α→8)-epigallocatechin (14) and epiafzelechin-(4β→8)epicatechin-(4β→8, 2β→O→β→7)-epicatechin-(4α→8)-epicatechin (15).

An 85-year-old man had a 2 vessel coronary disease. Preoperative echogram showed the lateral femoral circumflex artery (LFCA) had enough diameter and length. We performed coronary artery bypass grafting (OPCAB) with the left internal thoracic artery (LITA) and LFCA. Postoperative coronary angiogram showed that the LFCA bypass graft was patent and supplied sufficient blood to the anastomosed vessel.

Femoral neck fractures occurring in senior osteoporotic patients are closely related to bone fatigue. It is considered that the fatigue strength and durability of bone are decreased by the low metabolic activity in such cases. In this chapter, a theoretical analysis and an experimental study were carried out to estimate the progression of osteoporosis and the fatigue life of bone in living body. According to these studies, it was found that fatigue life is determined by the accumulation rate of mechanical damage and by self-healing activity. From these results, it is clear that remodeling activity varied with mechanical stimulation and that fatigue life is short in a high-frequency-cycle loading condition.

Progression of osteoporosis is caused by a decline in bone formation activity relative to the resorption activity. In this paper, the authors carried out a theoretical analysis of the progression of osteoporosis to estimate the osteoporotic change in the upper end of the femur. According to this analysis, the progression rate of osteoporosis in cancellous bone depends on the product of remodeling activity, Ract, and the trabecular structure parameter, Ktr. To confirm that the theoretical results were reasonably comparable to actual osteoporotic change, these two factors were measured in rabbits. From the results, it was concluded that the highest progression rate was shown in bar/bar-like trabecular structure (type 3); the next highest rate, was shown in plate/bar-like structure (type 2); and the plate/plate-like structure (type 1) was the most insensible. Furthermore, the bone volume fractions of cancellous bone were measured at the upper end of human femurs with and without osteoporosis. Then the measured value was compared with the theoretical value for each type of trabecular structure. Results showed that the decrease in bone volume fraction predicted by Eq. 7 was well in accord with the actual decrease.

Osteoporosis is such a desease that the bone volume decreases with aging. As the mechanism of osteoporosis, the following is accepted widely: the bone resorption exceeds relatively the bone formation owing to a decrease in bone metabolic activity. In the past, the present authors have analyzed theoretically the progressive rate of the osteoporosis generated in a cancellous bone, and have clarified that the dynamic change in bone volume density depends on the remodeling activity of bone as well as the structural characteristic of trabecular architecture.In order to confirm this theroy, an experimental study was carried out in this paper. Firstly, the real bone volume fraction was measured by using the upper end of the osteoporotic femur dissected from cadavers. Then the result was compared with the theroetical value. As a result, it was learned that the decreasing tendency of the density predicted by the theoretical equation was well in accordance with the actual one.

Twenty-seven cases with 30 hips of advanced coxarthrosis treated by valgus extension osteotomy (Bombelli) and valgus flexion osteotomy were investigated.Clinically, arevition of pain was notable.Roentugenologically, disappearance of bone sclerosis and pseudocyst made the trabecular structure normal. Joint space became remarkably wide and remodelled as a new joint. Some effects could be obtained as determined as a biomechanical analysis.However, capital drop may be considered to be a new femoral head adapting to a new acetabulum, formed as the result of biological restoration. In order to promote the remodelling of the hip joint using the capital drop most efficiently, the valgus flexion osteotomy seems to be more rational than the valgus extension osteotomy.

Fatigue fracture of artificial implants in the human body, caused by the repeated application of stress, is well documented. It is known that the fatigue strength of implant materials decreases when they are exposed under in vivo corrosion conditions. There are, however, no investigations concerning the effect of body fluids on the fatigue characteristics of commonly used biomaterials. Accordingly, fatigue tests on machined stainless-steel AISI 316, and COP alloy rods have been conducted in the right lower leg of rabbit. These specimens were pierced through the hole drilled at the middle of the tibial bone. A cyclic tensile stress of frequency 5 or 10 Hz was applied to the rods. From the results, it was found that the fatigue strength at 5 x 10(6) cycles for AISI 316 under the in vivo environment was 680 MPa compared to 830 MPa in air and similarly for COP alloy, was 680 MPa in the living body compared to 800 MPa in air. These remarkable changes in fatigue strength associated with the in vivo environments are considered to be due to the corrosive action of body fluids on the biomaterials.