Characterization of apatite formed on alkaline-heat-treated Ti.

Alkaline-heat-treated titanium self-forms an apatite surface layer in vivo. The aim of the present study was to materialistically characterize the surface of alkaline-heat-treated titanium immersed in simulated body fluid (AHS-TI) and to examine the differentiation behavior of osteoblasts on AHS-TI. SEM, thin-film XRD, FTIR, and XPS analyses revealed that AHS-TI contained a 1.0- micro m-thick, low-crystalline, and [002] direction-oriented carbonate apatite surface. Human osteoblast-like SaOS-2 cells were cultured on polystyrene, titanium, and AHS-TI, and RT-PCR analyses of osteogenic differentiation-related mRNAs were conducted. On AHS-TI, the expression of bone sialoprotein mRNA was up-regulated as compared with that on polystyrene and titanium (p < 0.05). On AHS-TI, the expression of osteopontin and osteocalcin mRNAs was up-regulated as compared with that on polystyrene (p<0.05). The results indicate that the apatite was bone-like and accelerated the osteogenic differentiation of SaOS-2, suggesting that alkaline-heat treatment might facilitate better integration of titanium implants with bone.

Activation of prophenoloxidase A1 by an activating enzyme in Drosophila melanogaster.

An activating enzyme for prophenoloxidase A1 was isolated from pupae of Drosophila melanogaster, and the activation of purified prophenoloxidase A1 with this enzyme was analyzed. The purification included ammonium sulfate fractionation, DEAE-cellulose, Superdex 75, arginine-Sepharose and hydroxyapatite column chromatography. The prophenoloxidase activating enzyme was determined to be a 28.5-kDa protein consisting of a single polypeptide. The kinetics of the activation reactions was unusual in that the final levels of phenoloxidase activity varied depending on the initial concentrations of the activating enzyme, not those of the prophenoloxidase. The activation was effectively suppressed by the inhibitors of trypsin-type serine protease. The protein has amidolytic activity, and Boc-Val-Pro-Arg-MCA was the best substrate among the synthetic substrates examined. The molecular mass of the activated phenoloxidase was smaller than that of the prophenoloxidase, indicating that a 5-kDa peptide was released from the prophenoloxidase by limited proteolysis with the activating enzyme. The cleavage site of prophenoloxidase A1 was shown to be between Arg and Phe at positions 52 and 53.

[Open-heart surgery without donor-blood transfusion--a clinical study].

Since October 1987, 80 patients underwent open-heart surgery without donor-blood transfusion. 50 (Group I) out of these 80 cases were selected to be paired with 50 patients (Group II) who underwent open-heart surgery with homologous blood transfusion in the same period. Twelve cases (Group III) underwent open-heart surgery without homologous blood transfusion but were transfused after surgery. To decrease the homologous blood requirements, ultra-filtration system as well as conservation and autotransfusion of autologous blood was employed. Peripheral blood count, blood chemistry for liver and renal function were analyzed and compared among these three groups. Although hematocrit of Group I was lower than that of Group II until the third postoperative day, there was no difference after the seventh postoperative day. The platelet count was more in Group I than in Group II or III on the first and the seventh postoperative day. The level of lactate dehydrogenase was higher in Group II than in Group I. Total bilirubin was more elevated in Group II than in Group I on the first and the fourteenth postoperative day. Direct bilirubin was also higher in Group II than in Group I till fourteenth postoperative day. Five cases in Group II fulfilled the criteria of the serum hepatitis. Blood urea nitrogen and creatinine were less in Group I than in Group II. The duration of the intra-tracheal intubation was shorter in Group I than in Group II or III. There was no difference in postoperative dosage or duration of catecholamines among three groups.(ABSTRACT TRUNCATED AT 250 WORDS)

[Functional pulmonary atresia: a case report].

A male neonate, two days of age, was admitted with cyanosis and tachypnea. Chest roentgenograms showed massive cardiomegaly and decreased pulmonary vasculatures. Echocardiographic and the right ventriculographic findings were interpreted as showing primary pulmonary atresia with secondary tricuspid incompetence. At a Brock operation, however, there was no resistance in passing the instrument through the pulmonary valve. The baby died twelve hours after surgery. Postmortem examination showed that the tricuspid regurgitation was a cause of the functional pulmonary atresia (FPA). It is important to distinguish FPA from pure pulmonary atresia because conservative therapy is the first choice for the FPA.

[Sudden onset of systemic hypoxia associated with both tricuspid regurgitation and persistent foramen ovale: a case report].

A 33-year-old female who had undergone closure of VSD 20 years before, was hospitalized for sudden onset of dyspnea without history of febrile or traumatic disorder. On admission, she had cyanotic lips and nailbeds but no clubbed finger. Chest x-ray film showed neither lung congestion nor cardiomegaly. Arterial blood gas analysis revealed deep hypoxia (PaO2 = 49.6 mmHg). Echocardiogram clarified massive tricuspid regurgitation (TR) due to chordal rupture of anterior leaflet, small VSD jet stream through the membranous aneurysm and a great deal of R-L shunt on the atrial level through a persistent foramen ovale. Cardiac catheterization data confirmed 35% of R-L shunt. At operation, a torn chordal tendon of anterior leaflet and an adhered septal leaflet to aneurysm of membranous portion of ventricular septum were seen. There were two pledgets, used at the first surgery, at the base of the aneurysm and a couple of tiny holes (VSDs) above and below the pledgets were recognized. Following resection of anterior and posterior leaflet, plication of septal leaflet and closure of VSD, a Xenograft valve (Carpentier-Edwards 29-M) was implanted. Then persistent foramen ovale, 20 x 20 mm in large, was closed directly. Her postoperative course was excellent with disappearance of cyanosis, normalized oxygen saturation in arterial blood and improved activity without dyspnea.

[A case report of cystic adventitial degeneration communicating with the hip joint in the external iliac artery].

Cystic adventitial degeneration is an uncommon cause of arterial obstruction. Its etiology is debated. We report a case in which the left external artery was affected and the cystic mass communicated with the hip joint. The findings of this case support the embryonic theory that the articular synovium and adventitial cysts have the same mesenchymal origin.

[Congenital bicuspid aortic valve associated with aberrant coronary artery origin: a case report].

A 61-year-old man with congenital bicuspid aortic valve associated with aberrant coronary artery origin is presented. His aortic valve was severely stenotic with marked calcification. At the aortic valve replacement, it was found that the valve was markedly calcified and the bicuspid valve and both coronary ostia were very close to each other in a posteriorly positioned sinus of Valsalva. There have been a few reports concerning the combination of the bicuspid aortic valve and aberrant coronary artery origin, and it is well known that the bicuspid aortic valve more frequently accompanies short left main trunk or left coronary arterial dominance than a normal aortic valve. Some genetic mechanisms surrounding the coronary artery, aortic valve and aorta are suggested to occur with such anomalies.

[Pure aortic valve regurgitation due to congenital bicuspid valve--analysis of 7 cases and a report of 2 rare cases].

The congenital bicuspid aortic valves usually become stenotic with severe calcification or regurgitant due to infective endocarditis (IE). However, pure aortic valve regurgitation without calcification or IE may be occurred. We report seven these cases out of 30 bicuspid valved patients who underwent aortic valve replacements. Pathological findings of these resected valves revealed neither calcium deposit nor findings of infection, but commonly showed myxoid degeneration. They were operated on at the mean age of 39, while those with calcified bicuspid aortic valves had an average age of 56. Two rare cases in whom an anomalous fibrous band on the larger cusp attached to the aortic wall were also reported.

Size disparity between donor and recipient in canine heart transplantation.

To assess the feasibility and function of small donor hearts for large recipients, small donor hearts were orthotopically transplanted into large recipients. Thirty adult mongrel dogs were used to form donor-recipient (D-R) combinations with the D-R heart weight ratio ranging from 0.47 to 1.78. In the D-R heart weight ratio of 0.8 or above (mean 1.11, Group I), the successful transplantation rate was 57 per cent, while it was 81 per cent in cases of less than 0.8 (mean 0.67, Group II) (no statistical difference). In 10 dogs (5 with D/R heart weight ratio greater than or equal to 0.8, 5 with less than 0.8) a recovery rate in cardiac function of the transplanted small heart was studied 2 hours following transplantation. There was no significant difference, hemodynamically in the normal range of left atrial pressure (LAP) between the two groups. The close relationship between cardiac output (CO) and volume load in the range of 10 to 15 mmHg of LAP was transformed to a linear function in the over 0.8 group. It was technically and hemodynamically possible to transplant small dog hearts to larger recipients up to the D-R heart weight ratio of 0.47. The importance of an adequate heart rate for the increase of CO in transplanted smaller donor hearts was emphasized.

[Acute and chronic experimental tricuspid valvular stenosis in dogs].

Acute and chronic experimental tricuspid valve stenosis was produced in 20 dogs. Clinical and hemodynamic alterations that resulted from severe anatomic tricuspid valve narrowing were surprisingly mild. In the acute stenosis studies, the normal tricuspid valve area of 8.2 +/- 0.3 sq cm was narrowed to less than 1.0 +/- 0.1 sq cm with a resulting right auricle-right ventricle diastolic gradient of 3.7 +/- 0.7 mm Hg. In chronic studies, a decrease in tricuspid valve area from 7.6 sq cm to 1.6 +/- 0.3 sq cm produced a diastolic gradient of 1.8 +/- 0.2 mm Hg. After 60 days, overt signs of right-sided failure (pleural effusions and ascites) were absent, and histological evidence of passive congestion (liver and spleen) was not recognized. The splanchnic vascular beds appear to act as excellent buffers against increases in right-sided cardiac pressure. We conclude that isolated narrowing of the tricuspid valve must be very severe to cause notable clinical and hemodynamic changes.