Interaction between the transcription factor SPBP and the positive cofactor RNF4. An interplay between protein binding zinc fingers.

The activator of stromelysin 1 gene transcription, SPBP, interacts with the RING finger protein RNF4. Both proteins are ubiquitously expressed and localized in the nucleus. RNF4 facilitates accumulation of specific SPBP-DNA complexes in vitro and acts as a positive cofactor in SPBP-mediated transactivation. SPBP harbors an internal zinc finger of the PHD/LAP type. This domain can form intra-chain protein-protein contacts in SPBP resulting in negative modulation of SPBP-RNF4 interaction.

Phlebotomy: a treatment of ischaemic necrosis of the femoral head? Analysis of a hypothesis.

The treatment of non-traumatic ischaemic osteonecrosis of the femoral head (ONFH) remains problematical and there is evidently scope to seek for a medical treatment of this disease which often leads to a surgical procedure for hip prosthesis. If we exclude the context of hemoglobin disorders, necrosis appears mainly in adults, when their limb bones contain a fatty marrow. Investigations such as intramedullary pressure measurement and transosseous phlebography suggest a disorder of the intraosseous blood circulation. Various studies in animals and man have provided arguments indicating that a kind of intraosseous 'obesity' due to hyperplasia and/or hypertrophy of the fatty tissue of the femoral marrow play a role in the development of necrosis. In this respect, the blood flow of the yellow marrow is close to ischemia, whereas red marrow flow can be very high. In various conditions, mainly hemolytic anemias, the femoral yellow marrow can convert to red marrow, which has also been described in anemias induced by blood loss. If it is not thought unreasonable to consider ONFH an 'ischemic' disease, these observations are an encouragement to attempt treatment by repeated phlebotomies. This procedure may locally restore red marrow, and then an adequate blood flow which could stabilize or even reverse the lesions if they are diagnosed early.

Acute neck pain and fever as the first manifestation of chondrocalcinosis with calcification of the transverse ligament of the atlas. Five case-reports with a literature review.

We report five cases of acute neck pain with fever in patients with diffuse articular chondrocalcinosis and computed tomography evidence of calcification of the transverse ligament of the atlas. A review of the relevant literature illustrated the high frequency of this condition, the variability of clinical presentations ranging from episodes of acute neck pain with fever to compression of the proximal spinal cord, the value of computed tomography for determining the site of the calcific deposits and assessing the lesions, and the possibility of deposition of both calcium pyrophosphate dihydrate and hydroxyapatite crystals in the same patient.

Calcification of the transverse ligament of the atlas in chondrocalcinosis: computed tomography study.

OBJECTIVE: To seek an association between articular chondrocalcinosis (AC) and calcification of the transverse ligament of the atlas (TLA), and to evaluate the frequency and the main computed tomography appearances of such calcification. METHODS: Axial computed tomography slices of the cervico-occipital hinge were performed routinely in 21 patients with AC (three men, 18 women; mean age 79 years, range 67-87) and compared with those from a control group of 21 age and gender matched patients without AC. RESULTS: Calcification of the TLA was present in 14 of the 21 patients (66%) in the AC group and in none of the 21 patients (0%) in the control group (chi 2 test: p < 0.001). Calcification was localised behind the odontoid process, inserted upon the osseous tubercles of the lateral masses of C1, and had a curvilinear profile; it varied in height (1.5 to 9 mm) and appearance (thin = < 1 mm; thick = > 1 mm) and formed either a single or a double band. CONCLUSION: This study has demonstrated a relationship between AC and calcification of the TLA. Although such calcification often remains asymptomatic (nine of 14 patients in our study), it may be associated with attacks of acute neck pain with segmentary stiffness, fever, and an increased erythrocyte sedimentation rate, sometimes revealing AC.

Tumor-like bone dystrophy and peripheral joint fusion in a patient with Paget's disease of bone.

The authors report an 80-year-old woman who was evaluated for pain in her left leg and ankle. Sixteen years earlier, she had received a diagnosis of monostotic Paget's disease at the same site, based on roentgenographic changes. The lesion was very unusual, with tumor-like lysis of the affected area and fusion of the tibia, fibula, and talus.

[Osteomyelitis in the pagetic tibia]. / Ostéomyélite sur tibia pagétique.

Osteomyelitis developing in pagetic bone is a very rare event, of which only one instance has been reported to date, in a patient with mandibular disease. We have managed three patients with osteomyelitis of a pagetic tibia. The portal of entry was a skin lesion in all three cases. A Gram-negative organism was found in all three cases and was associated with the anaerobe Bacteroides melaninogenicus in one case. One of the patients was lost to follow up before eradication of the infection. Amputation was required in the other two after unsuccessful antimicrobial therapy for 23 and four years, respectively.

[Paget's disease and metastatic epithelioma on the same bone. 11 new cases and review of the literature]. / Maladie de Paget et métastase d'épithéliomas sur le même os. Onze nouvelles observations et revue de la littérature.

The authors collected observations concerning 11 newly histologically proved cases of a combination of Paget's disease and carcinoma metastatic to bone on the same bone from members of the French Rheumatology Society. The most frequent locations can be specified from their analysis and an analysis of 26 detailed cases from the literature, i.e. pelvis, femur, rachis, tibia, humerus, and the cancers most frequently involved--prostate, bronchi, kidney, breast and intestine. The most usual histological appearance is osteolytic, except in the case of prostatic carcinoma. The metastasis reveals the presence of cancer in 2 cases out of 3, whereas Paget's disease is most often already diagnosed. A histological examination is necessary because of the risk of non recognition of such metastases or of confusion with sarcomatous degeneration. It does not appear to be exceptional to find Paget's disease in combination with a metastasis on the same bone. Although six of the cases concern metastases only located at sites of Paget's disease, an analysis of all the cases does not seem to indicate that Paget bone is more exposed to metastases than normal bone, since both diseases in fact locate preferentially at the same sites on the skeleton.

[Painful polyarticular syndrome probably induced by cyclosporin in three patients with a kidney transplant and one with a heart transplant]. / Syndrome algique polyarticulaire probablement induit par la ciclosporine (SAPPIC) chez trois transplantes renaux et un transplanté cardiaque.

Among others, ciclosporin had the advantage of decreasing appreciably the incidence of osteonecrosis after renal transplantation. However, the authors have isolated, in three renal transplant patients and one heart transplant patient, treated with ciclosporin, a new syndrome consisting of bilateral and symmetrical joint pain, affecting the lower extremities and lasting almost one year. Subsiding of the radiological aspect and the isotopic hyperfixation of the affected joints, at the end of the evolution, as well as the histological aspect of the bone surrounding the joints, remind somehow of algodystrophy. In both cases, the severity of the pain seemed to depend on the doses of ciclosporin, indicating that this molecule could play a role in the occurrence of this syndrome.

Is osteonecrosis of the femoral head avascular? Bone blood flow measurements after long-term treatment with corticosteroids.

Since nontraumatic osteonecrosis of the femoral head is usually considered primarily as an ischemic disease, blood flow has been studied in femoral segments in two groups of geese, one control group and the other treated with a high dose of corticosteroids for 5 months. There was no histologic evidence of osteonecrosis in femoral heads, and mean bone blood flow in any femoral segments was not reduced in the treated group. These results suggest that osteonecrosis of the femoral head is not caused primarily by ischemia, even if ischemia may play a secondary role in the evolution of the disorder.

How and what kind of bone is made by metastatic cells of prostatic cancer.

In 14 patients with densifying bone metastases of prostatic cancer, the analysis of blood and urine P-Ca parameters, serum 25 OH D3, Ca infusion test, and histomorphometry with measure of calcification rate shows that: - hypocalcemia is common in such patients, sometimes associated to a lack of vitamin D with hypocalciuria and increased Ca retention at the infusion test, and sometimes unexplained; - from a histological point of view, this osteopathy is characterized by a hyperosteoidosis, often an important one, around and only around the metastasis foci, the malignant cells being indispensable to induce the osteoidosis. The entire mineralization of the osteoid matrix may happen but rarely because the hyperosteoidosis is most often increased by a vitamin D deficiency.

[Biological and histological profile of osteomalacia in condensing prostatic osteosis. Apropos of 4 cases]. / Profil biologique et histologique d'ostéomalacie dans l'ostéose condensante prostatique. A propos de 4 observations.

The authors report on 4 cases of condensating prostatic osteosis, whose biological picture and histomorphometric lesions in the involved area indicate osteomalacia. They discuss the individual nature of such a syndrome, the links between vitamin D deficiency and hyperosteoidosis at a very slow noted speed of calcification, and the usefulness of investigating and treating the syndrome.