Toxicity of silica-containing calcium phosphate glasses demonstrated in mice.

Suspensions of calcium phosphate glass containing various concentrations of silica (glass composition (moles): 100 Ca(PO3)2 to x SiO2,x = 0, 5, 10, 15 or 40) dispersed in normal saline were injected intraperitoneally into C57BL/6 mice to determine the mortality within 30 days. The mortality was 0/10, 3/10, 9/10, 10/10 and 10/10 at x = 0, 5, 10, 15 and 40 mol of silica, respectively. By means of inductively coupled plasma analysis, the amount of dissolved silica (Si4+) in water at 37 degrees C from the calcium phosphate glass depended on the amount of silica in the glasses. The mortality of mice was directly proportional to the silica content of the glass injected intraperitoneally. These results clearly show that the dissolved silica (Si4+) from the glass, monomeric or low molecular silicic anion, is highly toxic. The SiO2 component in biomaterials has toxic potential when dissolved in the body.

HLA phenotypes in patients who have osteosarcoma.

Human leukocyte antigen (HLA) phenotypes were studied in twenty Japanese patients who had typical osteosarcoma. The HLA-A11 phenotype was found in ten (50 per cent) of the twenty patients, compared with 16.6 per cent of 235 control subjects (chi square = 13.248; p less than 0.0005)--an odds ratio of 5.026. These data suggest that major histocompatibility complex-linked genes may determine susceptibility to osteosarcoma.

Sternocostoclavicular hyperostosis. A report of nineteen cases, with special reference to etiology and treatment.

The cases of nineteen patients with sternocostoclavicular hyperostosis were reviewed retrospectively. Of particular interest were the responses to antibiotics and prostaglandin inhibitors. The prostaglandin inhibitors relieved the pain within three to four weeks in sixteen of eighteen patients so treated. However, the inhibitors gradually became less effective in most patients. Oral antibiotics were more effective than the inhibitors in relieving the pain of eight of the eleven patients who were given antibiotics. Pustulosis palmaris and plantaris, commonly associated with sternocostoclavicular hyperostosis, diminished after antibiotic therapy, as did the chest pain in most patients. The similarities between the age and sex distributions and the responses to antibiotics of the patients with sternocostoclavicular hyperostosis and those with pustulosis suggest that these disorders have a common etiology, and that the pustulosis may be a so-called bacterid reaction and the hyperostosis, a manifestation of a systemic reaction to a focal infection.

Characteristics of the isokinetic performance of patients with injured cruciate ligaments.

The torques of the quadriceps muscle in patients with cruciate ligament injuries were evaluated under isokinetic contraction. There were 30 patients with anterior cruciate ligament injuries, 19 with posterior cruciate ligament injuries, and 30 controls. The torques of concentric and eccentric contractions in anterior cruciate ligament-injured knees showed a significant difference from those in the uninjured sides at extension angles of less than 45 degrees, yet the values of the peak torques for concentric and eccentric contractions were the same as those for the uninjured sides. The torques of concentric and eccentric contractions in posterior cruciate ligament-injured knees showed a significant difference from the uninjured sides at flexion angles of more than 36 degrees. The peak torques for concentric and eccentric contraction also showed a significant difference from the uninjured sides. The concentric and eccentric peak torque angles of the injured knees were similar to those of the uninjured sides in all subjects. The ratios of eccentric to concentric peak torque of the contralateral knees in the anterior cruciate ligament-injured groups did not show a significant difference from those of the controls. The evaluation of the biomechanical change in these categories is of great advantage in determining proper methods of treatment and rehabilitation.

The aetiology and treatment of simple bone cysts.

The internal pressure of simple bone cysts was found to be slightly higher than the normal pressure of the bone marrow in the contralateral limb. The pressure within the cyst was measured during drilling with a Kirschner wire; it gradually decreased as the number of drill-holes increased. The PO2 of the cyst fluid was markedly lower than that of either venous or arterial blood measured synchronously. It is suggested that venous obstruction in the bone is the likely cause of these cysts. Seven patients with simple bone cysts were treated by the multiple drill-hole method, and the clinical outcome was excellent. Multiple drilling may prove to be the treatment of choice for simple bone cysts in the younger patient, as it presents fewer hazards than other procedures.

Fracture of the posterior medial tubercle of the talus treated by internal fixation: a report of two cases.

A fracture through the posterior medial tubercle of the talus is quite rare. Although excision of the bone fragments has been reported previously in this fracture, cases of internal fixation of the posterior medial tubercle of the talus have not been reported. Two patients are described who presented with a fracture through the posterior medial tubercle of the talus which was treated with internal fixation. Our patients appeared normal on physical examination and returned to work, with no evidence of avascular necrosis of the fragments.

[Combination effect of pirarubicin, ifosfamide, and vincristine sulfate in the treatment of advanced synovial sarcoma--report of a case].

Synovial sarcoma with pulmonary metastases appeared to be sensitive to multiagent chemotherapy of Pirarubicin, Ifosfamide, and Vincristine Sulfate. However, this chemotherapy regimen could not be continued because of severe hemorrhagic cystitis due to the toxicity of Ifosfamide. Even in the advanced stage, this multiagent chemotherapy would be useful for the treatment of synovial sarcoma, if hemorrhagic cystitis could be prevented.

Transient osteoporosis of the hip in the first trimester of pregnancy. A case report and review of Japanese literature.

A patient with transient osteoporosis of the hip in her first trimester of pregnancy is reported in this study. Rapid symptomatic improvement after artificial abortion was observed. These findings exclude pressure on the obturator nerve, Sudeck's osteodystrophy, venous obstruction, and excessive demand of proteins and calcium in the etiology of this condition. Rather it is here suggested that chemical or hormonal factors related to pregnancy play an important role in the etiology.

[Identification of serum alkaline phosphatase from human bone].

Polyacrylamide gel electrophoresis utilizing sodium dodecyl sulfate followed by specific staining for alkaline phosphatase was accomplished using sera from patients with osteosarcoma, polyostotic fibrous dysplasia, metastatic bone tumor, and idiopathic hyper-alkalinephosphatasemia. Alkaline phosphatase activity of the sera was uniformly demonstrated at a molecular weight of 60,000. L-homoarginine more strongly inhibited the alkaline phosphatase activity than did L-phenylalanine. Alkaline phosphatase activity was markedly inactivated by heating. Regarding substrate specificity, the hydrolysis of p-nitro-phenylphosphate occurred at a lower rate than did that of phenylphosphate. By contrast, the hydrolysis of alpha- and beta-glycerophosphate occurred at a higher rate than did that of phenylphosphate. As seen from the data presented here, the serum alkaline phosphatase samples obtained from these patients with skeletal disorders have several common characteristics.

[Simple bone cyst--pathophysiology and treatment].

Internal pressure of simple bone cyst was slightly higher than normal bone marrow pressure measured on contralateral side. Internal pressure of the cyst measured during drill-holing with Kirschner wire gradually decreased along with the increase in the number of drill-holes. Internal PO2 was markedly lower than PO2 of venous and arterial blood measured synchronously. Venous obstruction in bone may be an etiology of simple bone cyst. Follow up study showed that all cysts of six cases treated by the multiple drill-hole method were filled up with bony tissue within five months after the treatment, and the clinical result of the treatment was excellent. Multiple drill-hole method may be the first choice in the treatment of simple bone cyst in the younger patients, because the operative invasion of this method was minimum.

[Immunoglobulin G coating of ceramic powders enhances superoxide production].

Crystals and a group of ceramics used in joint replacement surgery were incubated with polymorphonuclear cells with and without adsorbed immunoglobulin G to study their ability to generate superoxide anion. All eight particles tested had the capacity to induce superoxide anion to at least some extent. Alumina ceramic and some of the ceramics adsorbed small amounts of immunoglobulin G onto their surfaces and the increment of superoxide production was also small. Both the augmentation of superoxide anion and the adsorption of immunoglobulin G to tricalcium phosphate ceramic and the remaining ceramics were intermediate. Synthetic monosodium urate crystals adsorbed immunoglobulin G most efficiently with large increments of superoxide anion. The increase in superoxide production by the adsorption of immunoglobulin G depended on the amount of immunoglobulin G bound onto crystals or ceramics. The greater phlogistic potential of some ceramics need to be taken into consideration in their clinical use.

[Prolonged inflammatory reactions induced by ceramic powders in the rat air pouch model].

The subcutaneous air pouch of the male Sprague-Dawley rat was used to study inflammatory potential of artificial ceramics. Local leukocyte influx, proteinase, prostaglandin E2 (PGE2) and tumor necrosis factor (TNF) levels were measured after injection of hydroxyapatite ceramic (HAP), tricalcium phosphate ceramic (TCP) and apatite-wollastonite glass ceramic (GC) into the pouch. Synthetic monosodium urate crystals (MSU) were used as positive controls and normal saline (NS) as a negative control. The response was monitored over a period of 168 hours by irrigating the pouch with 5 ml of NS and withdrawing 4 ml. MSU produced the greatest response in leukocyte counts, proteinase and PGE2, whereas HAP, TCP and GC often appeared later than with MSU. TNF was significantly detected only after ceramics and not after MSU. The chronic and relatively prolonged reaction to HAP, TCP and GC suggests that an inflammatory reaction may occur after implantation of these ceramics in humans. The increased levels of TNF and production of PGE2, which are substances proposed to contribute to osteolysis associated with loosening, are of special interest for further research.

Anatomy and pathophysiology of the popliteal tendon area in the lateral meniscus: 1. Arthroscopic and anatomical investigation.

An arthroscopic and anatomical investigation was performed to define the abnormal conditions of the popliteal tendon area in a lateral meniscus. Arthroscopic findings for 100 patients and anatomical observations of 10 amputated knees were analyzed. Five of the 10 dissected menisci were also examined histologically. Menisco-tibial coronary ligaments were classified into two types, as follows: type I--a coronary ligament covering an entire popliteal tendon beneath the meniscus; type II--a popliteal tendon visible beneath the meniscus through defects of the coronary ligament. Twenty-one of 100 cases were classified as type I, and 79 were classified as type II. Three of the 10 anatomical dissections were type I, and the remaining 7 were type II. Menisci in which the type I coronary ligaments were thought to be torn and menisci with type II coronary ligaments showed a rather marked mobility, but no conclusion could be reached.

Anatomy and pathophysiology of the popliteal tendon area in the lateral meniscus: 2. Clinical investigation.

Treatment of abnormal mobility of the popliteal tendon area of the lateral meniscus is described. Twenty-seven patients who exhibited an abnormally mobile posterior segment with no obvious ruptures in the lateral meniscus were directly examined by us after an average of 4 years and 3 months from the time of the arthroscopic procedure. The main complaints associated with this condition before the surgery were pain and locking during deep knee flexions. The patients were divided into three groups according to surgical method: partial meniscectomy, subtotal meniscectomy, or meniscal repair. The subtotal meniscectomy and repair groups showed significantly higher scores than the partial meniscectomy group. A locking phenomenon recurred in one case of the meniscal repair group. In this case, the menisco-femoral coronary ligament posterior to the popliteal tunnel could not be sutured.

[The effect of biomaterials on cytochrome c].

The adsorption of ferricytochrome c and ferrocytochrome c on biomaterials was studied by measuring the spectrum of samples assuming the molar extinction coefficients of the ferricytochrome c and ferrocytochrome c at 480 nm and 550 nm. Silica, alumina ceramic, zirconium ceramic, tricalcium phosphate ceramic, hydroxyapatite ceramic, unidirectional calcium phosphate glass-ceramic, bulk crystallized calcium phosphate glass-ceramic and bulk crystallized calcium phosphate glass-ceramic containing large amount of titanium were used as adsorbents. The adsorption of ferricytochrome c or ferrocytochrome c on silica essentially followed the Langumuir adsorption isotherm. Quantitative analysis showed that ferricytochrome c was adsorbed more and dissolved less than ferrocytochrome c on batch adsorption on silica. Total amounts of adsorbed and non-adsorbed ferricytochrome c increased significantly in batch adsorption of ferrocytochrome c on silica. From these experiments it appears that materials such as silica induce a transfer of electrons of cytochrome c.

Malignant squamous cell carcinoma arising in a lumbar dermoid cyst. A case report.

A case of malignant transformation to a squamous cell carcinoma in a long-standing lumbar dermoid cyst is described. Progress was slow during 6 years. This type of transformation in a dermoid cyst is extremely uncommon and has never been recorded at this site.

Entrapment neuropathy of the deep peroneal nerve associated with the extensor hallucis brevis.

The authors report a case of entrapment neuropathy of the deep peroneal nerve associated with the extensor hallucis brevis. This entrapment neuropathy was found distal to the inferior retinaculum that causes the anterior tarsal tunnel syndrome. Surgical decompression of the deep peroneal nerve that was entrapped by the extensor hallucis brevis relieved the symptoms. This condition, like the anterior tarsal tunnel syndrome, deserves attention.

[Renal function after TKR in patients with rheumatoid arthritis who have chronic renal insufficiency].

Twenty three patients with RA who have chronic renal insufficiency were post operatively studied for changes in the renal function with TKR (total knee replacement). We evaluated the renal function by BUN, Creatine, PSP and Creatine clearance. The renal function has not grown worse in all cases. TKR is a safe operation for renal function with careful technique and management.

[Basic characteristics of Gunma clone-4 in the experimental study of metastasis].

Gunma clone-4 (Gc-4) cell was isolated by limiting dilution method from Radiological Science-Chiba- Toyama sarcoma which appeared spontaneously in a C3H/He mouse and cultured for generations. The character of Gc-4 cells was as follows: Gc-4 cells grew exponentially in vivo and in vitro, and the doubling time was 3.4 to 4.2 days in vivo and 20 to 22 hours in vitro respectively. Inoculation of 1 X 10(6) Gc-4 cells into A/Jackson mice and C57BL/6 mice resulted in rejection and disappearance within 17 days. Inoculation of 1 X 10(6) Gc-4 cells into C3H/He mice which were immunized with Gc-4 cells treated with 100 micrograms/ml of mitomycin C for 30 min. did not result in rejection. The Gc-4 cells showed histiocytic and fibroblastic characteristics morphologically and functionally, and corresponded to human malignant fibrous histiocytoma. Experiments on artificial and natural metastasis of Gc-4 cells revealed that Gc-4 cells had a high colony forming efficiency.