Long-term stability of self-assembled monolayers on 316L stainless steel.

316L stainless steel (316L SS) has been extensively used for making orthopedic, dental and cardiovascular implants. The use of phosphonic acid self-assembled monolayers (SAMs) on 316L SS has been previously explored for potential biomedical applications. In this study, we have investigated the long-term stability of methyl (-CH(3)) and carboxylic acid (-COOH)-terminated phosphonic acid SAMs on 316L under physiological conditions. The stability of SAMs on mechanically polished and electropolished 316L SS was also investigated as a part of this study. Well-ordered and uniform -CH(3)- and -COOH-terminated SAMs were coated on mechanically polished and electropolished 316L SS surfaces. The long-term stability of SAMs on 316L SS was investigated for up to 28 days in Tris-buffered saline (TBS) at 37 degrees C using x-ray photoelectron spectroscopy, atomic force microscopy and contact angle goniometry. A significant amount of phosphonic acid molecules was desorbed from the 316L SS surfaces within 1 to 7 days of TBS immersion followed by a slow desorption of molecules over the remaining days. The -COOH-terminated SAM was found to be more stable than the -CH(3)-terminated SAM on both mechanically and electropolished surfaces. No significant differences in the desorption behavior of SAMs were observed between mechanically and electropolished 316L SS surfaces.

Headspace gas chromatographic determination of 2-alkyl-5,5-dimethyl-1,3-dioxane derivatives in wastewaters of a polyester resin plant.

The static headspace gas chromatographic technique can be conveniently employed to check the presence and amount of the odorous side-products, 2-R-1,3-dioxanes (R = H, CH3, C2H5, i-C3H7, n-C3H7), directly from the wastewaters flowing from the reactors during the synthesis of polyester resins. By the optimisation of a simple and direct analytical method, the amounts of these compounds may be continuously monitored and controlled. This method is characterized by good repeatability (3-4%) and does not seem to suffer from matrix effects. The detection limits for the determination of the five dioxanes fall in the range 400-700 micrograms dm-3 (alpha = beta = 0.05).

The interaction of tributyllead with lysosomes from rat liver.

The interactions of tributyllead with lysosomes from rat liver have been studied. It results that the organometal compound induces a fast alkalinization in energized lysosomes. The interpretation is that the compound is a potent proton carrier. This function could explain the toxicity, in particular at neurological level of the compound.

Subacute hematogenous osteomyelitis: are biopsy and surgery always indicated?

Forty-four consecutive cases of subacute osteomyelitis admitted at our institution over a 12-year period were retrospectively reviewed to assess the effectiveness of conservative versus surgical treatment of this condition and to determine the indications for open biopsy and surgical debridement. Twenty-four cases were treated with antibiotics only, and 20 had surgical debridement followed by antibiotics. Except for one case that received inadequate antibiotic therapy, all patients responded well to this treatment, whether conservative or surgical. At an average follow-up of 18 months, there were no recurrences. Our results also showed that with a careful radiologic assessment of these cases, most lesions showed characteristic benign radiologic features. We can therefore conclude that conservative management of cases of subacute osteomyelitis is as effective as surgical treatment. We believe that conservative treatment with antibiotics should be the first line of management in most of these cases and that open biopsy or surgical debridement or both should be reserved for cases that do not respond to antibiotics or show aggressive radiologic features.

Malignant fibrous histiocytoma in a patient with Blackfan-Diamond anemia.

Blackfan-Diamond anemia, a chronic, pure red cell aplasia, is rare. Malignant fibrous histiocytoma is also uncommon; it can arise in pre-existing bone lesions. The authors describe a 23-year-old man with Blackfan-Diamond anemia complicated by hemochromatosis in whom malignant fibrous histiocytoma developed in the distal femur.

The value of computed tomography for the diagnosis of recurrent patellar subluxation in adolescents.

OBJECTIVE: To determine if computed tomography of the patellofemoral joint has any advantage over standard radiologic techniques in the evaluation of recurrent patellar subluxation. DESIGN: A case series. SETTING: A tertiary children's hospital out-patient clinic. PARTICIPANTS: Forty consecutive adolescents with a clinical diagnosis of recurrent patellar subluxation (study group) and 14 volunteers with normal knees (control group). INTERVENTIONS: A standardized radiologic protocol, including axial views of the patella at 30 degrees of knee flexion, with and without external torsion of the tibia, and computed tomography (CT) of the patella at 15 degrees of knee flexion. MAIN OUTCOME MEASURES: The lateral patellofemoral angle on the axial views and on the CT scan and patellar centralization on the CT scan. RESULTS: In the control group, no radiologic evidence of recurrent patellar subluxation was found. In the study group, an abnormal lateral patellofemoral angle was found in 25% of axial views; this rate increased to 42% with external rotation and 86% on the CT scan. Patellar centralization was abnormal in 79% of cases. CONCLUSIONS: CT of the patellofemoral joint is more sensitive than standard radiographs for the diagnosis of recurrent patellar subluxation. The use of CT is recommended when standard radiographs appear normal.

Synoviorthesis with colloidal 32P chromic phosphate for the treatment of hemophilic arthropathy.

Between 1977 and 1992, we performed ninety-two synoviortheses (destruction of synovial tissue by intra-articular injection of a radioactive agent) on forty-eight patients who had a severe congenital disorder of hemostasis and chronic hemophilic synovitis that was resistant to conventional treatment. Colloidal 32P chromic phosphate was injected intra-articularly: 1.0 millicurie for knees and 0.5 millicurie for other joints. The duration of follow-up ranged from one to fifteen years. The frequency and importance of bleeding decreased in most of the patients. The range of motion of half of the joints remained stable or improved and that of the other half continued to decrease. Radiographic scores worsened progressively despite the decreased frequency of hemarthrosis. In most patients, the extra-articular leakage of the radioactive agent was slight. Chromosome breakages were observed almost exclusively in patients who were seropositive for human immunodeficiency virus and in whom the CD4-lymphocyte count was decreased from normal. The patients' level of satisfaction with the results was high.

CT evaluation of primary epiphyseal bone abscesses.

We reviewed the clinical, radiographic, and computed tomographic (CT) findings in eight children with a histologically proven diagnosis of epiphyseal or apophyseal osteomyelitis. In all cases the femur was involved: in five the osteomyelitis was localized in the femoral condyle, in two it was in the greater trochanter, and in one it was in the femoral head epiphysis. In four of the six cases of epiphyseal involvement there was associated joint effusion or septic arthritis. CT examination may demonstrate a serpentine tract, a sequestrum, cortical destruction or adjacent soft tissue swelling and can differentiate osteomyelitis from other epiphyseal lucent lesions, particularly chondroblastoma and osteoid osteoma. CT yielded important new diagnostic information in seven of the eight patients, failing to do so in only one. In one case, CT showed a wooden splinter in an abscess cavity, which had been mistaken for a sequestrum. When combined with accurate clinical and laboratory information and good quality plain radiographs, CT can lead to an early diagnosis of epiphyseal infection. Early diagnosis helps avoid delays in initiating antibiotic or surgical treatment caused by the unusual (epiphyseal or apophyseal) location of the bone abscess.

Neonatal Volkmann's ischemic contracture of the forearm: a report of five cases.

We report five cases of children born with forearm wounds associated with motor and sensory losses to the hand and forearm. Their evolution toward muscle retraction is very similar to the classic description of Volkmann's ischemic contracture. These cases should not be confused with upper extremity gangrene of the newborn or aplasia cutis congenita. Two cases of neonatal Volkmann's ischemia have already been reported in the literature and identified as such. Another very similar case has been reported as upper extremity gangrene of the newborn, and three more cases of a forearm wound with neuromuscular involvement have been reported as aplasia cutis congenita. We believe that neonatal Volkmann's ischemic contracture of the forearm should be recognized as a separate entity. Its early diagnosis may improve treatment, especially for children with recent injury, in whom intracompartmental pressures may still be elevated. Early hand therapy and splinting are mandatory to minimize late sequelae.

Epstein-Barr virus polymorphic B-cell lymphoma associated with leukemia and with congenital immunodeficiencies.

Polymorphic B-cell lymphoma seen in four patients with congenital immunodeficiencies and in two patients with leukemia receiving chemotherapy was associated with the Epstein-Barr virus (EBV). The tumors had characteristic histologic features: they were polymorphic consisting of a mixture of lymphoblasts and differentiated cells including plasma cells, and areas of hemorrhagic necrosis were prominent. The tumors were either polyclonal, monoclonal, or multiclonal. Patients with congenital immunodeficiencies who developed these tumors died despite radiotherapy, corticosteroids plus acyclovir, or a combination of intravenous (IV) immunoglobulins and alpha 2 interferon. Patients with leukemia recovered when immunosuppressive drugs were discontinued and leukemia has not recurred over a period of 2 and 4 years, respectively, in the two patients.

[Chondromyxoid fibroma: radiologic and radioisotope aspects]. / Fibrome chondromyxoïde: aspects radiologique et radio-isotopique.

Chondromyxoid fibroma is a relatively rare benign bone tumor whose histologic and radiologic patterns are well known. In this article, we describe a 16-year-old boy with such a tumor in his left tibia. Scintigraphically, this tumor is represented by a "doughnut sign". This aspect, though not pathognomonic, has been reported sporadically in a few diseases: osteoporosis circumscripta cranii, angioblastic meningioma, cranial coccidioidomycosis, and aseptic necrosis of frontal bone. Because of their sites, it is easy to reject these diagnoses in our patient. The most pertinent differential diagnosis with regard to the clinical, radiological, and scintigraphic aspects in the patient is that of a giant cell tumor.

Primary bone tumours of the hand. Report of 21 cases.

Twenty-one primary bone tumours of the hand in children from 8 paediatric hospitals are reported. Osteochondromas and enchondromas were not included. Our material consisted of 16 patients with common tumours (3 Ewing's sarcoma, 5 aneurysmal bone cyst, 6 osteoid osteoma and 2 epidermoid cyst) and 5 patients with uncommon tumours (osteoma, simple bone cyst, haemangiopericytoma, capillary angiomatous tumour and benign ossifying fibroma or osteoblastoma). The X-ray diagnosis of the common tumours should have high concordance with histology, whereas that of uncommon tumours is much more difficult and uncertain. The characteristic features of Ewing's sarcoma are stressed as all our children with this tumour had a delayed diagnosis and a fatal outcome. Differential diagnosis with other short tubular bone lesions of the hand - specifically osteomyelitis - is discussed and the possibilities of microscopic diagnosis are stressed.

[Chronic sclerosing osteomyelitis (so-called Garré's). Review of 12 cases]. / Ostéomyélite chronique sclérosante (dite de Garré). Revue de douze cas.

This study reports 12 cases of chronic sclerosing osteomyelitis in children. The authors recall the past history of this disease and describe the clinical, radiological and pathological picture found nowadays. They insist upon the salient features that allow to differentiate this lesion from other types of infectious osteomyelitis and osteoid osteoma.

Subperiosteal osteoid osteoma of the talus.

We report three patients with subperiosteal osteoid osteoma of the talus. All showed an erosion of the dorsal surface of the talus with medullary bone sclerosis. Adjacent paraosseous soft tissue calcification was seen in two lesions. Computed tomography demonstrated the nidus of the osteoid osteoma in two cases.

Osteoid osteoma and osteoblastoma of the spine in children. Report of 22 cases with brief literature review.

Thirteen cases of osteoid osteoma and nine cases of osteoblastoma are reported. Diagnostic difficulties of osteoblastoma are illustrated by the versatile radiographic appearances of this tumour. The authors stress the importance of nuclear scan and CT in diagnosis and management.

[A case of osteoid osteoma of the femoral head epiphysis in a 9-year-old child]. / Un cas d'ostéome ostéoïde de l'épiphyse de la tête fémorale chez un enfant de 9 ans.

The authors describe an osteoid osteoma of the upper femoral epiphysis in a child of nine years. Healing was obtained after trans-articular curettage through an anterior approach. The authors have found no other similar case in the literature.