Expression of the angiomatrix and angiogenic proteins CYR61, CTGF, and VEGF in osteonecrosis of the femoral head.

Angiogenesis and bone repair are closely linked processes. VEGF, CYR61, and CTGF have been identified as signaling factors that control angiogenesis and could be important in fracture healing. The purpose of this study was to investigate the expression of these signaling factors in osteonecrosis of the femoral head. Twenty-one bone cylinders were retrieved from hips of patients with osteonecrosis of the femoral head at different ARCO stages. Immunohistochemistry for CD34, CYR61, CTGF, and VEGF expression was done on each bone cylinder representing the different regions of osteonecrosis (necrosis, fibrosis, transition zone, and edematous area). VEGF, CYR61, and CTGF were expressed in samples with osteonecrosis. Particularly VEGF and CYR61 were highly expressed in the edematous area. CYR61 was also highly expressed in the transition zone. CTGF was expressed mainly in the area of marrow fibrosis and edema. CYR61, CTGF, and VEGF are expressed to different degrees in the different repair zones of osteonecrosis. Particularly, the high expression of VEGF and CYR61 in the edematous area may represent a consequence of hypoxia and indicate a role of these proteins in the repair processes ongoing in osteonecrosis.

Expression of EDA+ and EDB+ fibronectin splice variants in bone.

The extracellular matrix component fibronectin (fn) has fundamental functions in cell attachment, differentiation, proliferation, and migration. Isoforms of cellular fibronectin, named EDA+ fibronectin or embryonal EDB+ fibronectin, are generated by alternative splicing of its mRNA precursors. Little is known about the expression of EDA+ and EDB+ fibronectin splice variants in human bone. The aim of this study was to investigate the expression pattern of fibronectin splice variants in bone cell lines and in different human bone tissue samples (mature bone, early stages of fracture healing, hypotrophic nonunion, osteosarcoma). Analysis was done by immunostaining with recombinant and monoclonal antibodies, qualitative RT-PCR and LightCycler-based real-time quantitative RT-PCR assay. In osteoblast and osteosarcoma cell lines, abundant expression of EDA+ and EDB+ fibronectin was found in immunocytochemistry. High transcription levels of both splice variants mRNA were seen in quantitative RT-PCR in osteosarcoma cell lines. In mature bone, EDA+ and EDB+ were not detectable in immunohistochemistry. Transcription of mRNA in both splice variants was absent in these samples. Early stages of fracture healing and osteosarcoma cell samples exhibited extensive staining for EDA+ and EDB+ fibronectin, and high mRNA levels were found. Both osteosarcoma and bone fracture healing tissue expressed high mRNA levels of the fibronectin splice variants independent of benign or malignant behavior. Low level of EDA+ fibronectin mRNA transcription and focal immunohistochemical staining of EDA+ fibronectin was found in hypotrophic nonunions, whereas EDB+ fibronectin was not detected by immunohistochemistry and qualitative or quantitative PCR. EDA+ fibronectin was found in granulation tissue-forming processes in bone independent from bone-forming activity. EDB+ fibronectin was seen only in high-turnover new osteoid-forming processes like early stages of fracture healing and osteosarcoma and was absent in low-turnover processes like mature bone and hypotrophic nonunion. Both EDA+ and EDB+ fibronectin mark active processes in bone without differentiation between malignant or benign activity. In conclusion, EDA+ and EDB+ fibronectin splice variants are strong markers for active fibrogenetic and osteoid-forming processes in human bones.

Lemierre's syndrome: the forgotten disease. An unusual presentation of sepsis.

A 19-year-old girl presented with a septical condition with fever of 40 degrees C, swelling of the right sternocleidomastoid region and abdominal pain. Except for a sore throat with pain strictly localized to the right side of her neck and fever over the last week there were no other clues in her past medical history. An abdominal ultrasound and MRT scan as well as a chest X-ray only showed non-specific findings. The diagnosis of Lemierre's syndrome was established by ultrasonographical detection of right jugular venous thrombosis and perivascular inflammation together with blood cultures positive for Fusobacteria. The patient recovered within days after treatment was initiated with metronidazol according to the antibiogram. Lemierre's syndrome is a life-threatening disease especially in an age group which is less frequently affected by septicaemia. A history of sore throat, Fusobacterium positive blood cultures and ultrasonographical detection of jugular venous thrombophlebitis together with the knowledge of the "forgotten disease" will lead the way to the diagnosis.

[Phosphoinositide 3-kinase (PI3-K) expression. Tumorigenesis of epithelial carcinoma of the mouth]. / Phosphoinositid-3-Kinase- (PI3-K) Expression. Tumorgenese von Plattenepithelkarzinomen der Mundhöhle.

Phosphoinositide 3-kinase (PI3-K) is a heterodimeric enzyme involved in the regulation of mitogenesis, apoptosis, cell adhesion, and motility. PI3-K was suggested as a protooncogene in human cancer. To determine the expression of PI3-K during cancerogenesis and tumor invasion of HNSCC, we investigated normal and dysplastic epithelium of the oral cavity, squamous cell carcinoma and lymph node metastasis by immunohistochemistry. The strongest immunoreactivity for p85alpha and p110alpha was found in invasive tumors and their metastases. Carcinomas in situ showed a focal positivity. Dysplasias and normal epithelium reacted predominantly negatively. The PI3-K inhibitor LY294002 inhibited proliferation and invasion of the HNSCC cell line CAL-27 and induced apoptosis in vitro. Our data suggest PI3-K as a marker of malignancy and tumor invasion. We suggest including PI3-K in the multistep carcinogenesis model of HNSCC. In addition, PI3-K is a potential target for pharmacological intervention.

[Secretin-stimulated MR cholangiopancreatography (MRCP): visualization of the normal pancreatic duct in comparison with ERCP]. / Sekretinstimulierte Magnetresonanzcholangiopankreatikographie: Darstellung des normalen Pankreasgangs im Vergleich zur ERCP.

PURPOSE: To determine whether the application of secretin improves the depiction of the normal pancreatic duct and to document the time course of any possible improved visualisation. PATIENTS AND METHODS: Twenty-eight patients with a normal pancreatic ductal system, proved by ERCP, were prospectively enrolled in our study. MRCP was carried out in a 1.0 Tesla unit using a thick slab single-shot turbo-echo sequence (TR: infinity, TE: 1100 ms, FA: 150 degrees, slab thickness: 65 mm). Following acquisition of a non-enhanced image, 1 clinical unit/kg bodyweight of secretin was injected intravenously. During the subsequent ten minutes the MR measurement was repeated every 30 seconds. The images were independently evaluated by two investigators. RESULTS: The improvement in quality after administration of secretin was statistically significant for both investigators (p < 0.05), but no significant difference was found between both investigators concerning the quality of the images (p = 0.49). Prior to the secretin application, the entire ductal system only be evaluated in ten cases (35.7 %) by both investigators, afterwards in 26 cases (92.9 %). Improvement was achieved after a mean time of 1.5 minutes and lasted until the ninth minute. CONCLUSION: Intravenous application of secretin improves image quality of MRCP also in patients with no pancreatic pathology. Improvement begins after 1.5 minutes and lasts for about seven minutes.

Magnetic resonance hydrometry: non-invasive quantification of the exocrine pancreatic function.

AIMS: To show the ability of magnetic resonance hydrometry (MRH) to quantify the pancreatic secretion after secretin stimulation in order to distinguish between physiological excretion and reduced output in chronic pancreatitis. METHODS: MRH images were acquired in a 1.0-T-clinical scanner using a body-array coil and a heavily T2-weighted standard single-shot TSE sequence. Thirty-one patients (14 male/17 female) who routinely underwent ERCP for suspected choledocholithiasis (n = 22), recurring abdominal pain (n = 1), icterus (n = 6 and suspected pancreatitis (n = 2) were included. During the investigation 1 CU/kg BW secretin were administered intravenously. Secreted volume of fluid, start of secretion, achievement of a plateau of secretion and a combined score of these parameters (MRH score) were assessed and evaluated. Sensitivity and specificity were calculated for these parameters. RESULTS: 27 patients had no pancreatic pathology, and four suffered from chronic pancreatitis. Patients without pancreatic disorders produced a mean pancreatic fluid volume of 183 plus minus 86 mL, whereas patients with chronic pancreatitis secreted 61 +/- 39 mL. Secretion started after a mean time of 95 +/- 94 seconds (no pancreatic impairment) and 62 +/- 13 seconds (chronic pancreatitis). The MRH score achieved a high accuracy in the detection of chronic pancreatitis. CONCLUSIONS: Our study demonstrated the feasibility of measuring pancreatic output by MRH after stimulation with secretin. Moreover, a distinction between normal secretion and patients with chronic pancreatitis is possible.

[Cellular senescence: a mechanism of the development of osteoporosis?]. / Zelluläre Seneszenz--ein Mechanismus der Osteoporoseentstehung?

Osteoporosis is one of the most common diseases of the elderly. This leads to the hypothesis that the ageing of the organism is reflected as a cytogerontological effect in a specific loss of bone cell function. Three underlying pathogenetic mechanisms need to be considered: (1) cellular aging in general, (2) impairment of the systemic stimulation of bone formation by e.g. decreasing hormone levels, and (3) lower cellular effectiveness of cytokines and growth factors. Cellular aging consists of replicative and postmitotic senescence. While the replicative senescence limits only the number of cell cycles, the postmitotic aging is influenced by endo- and exogenous factors. These lead to genetic alterations known as delayed persistent genomic instability and to an increasing impairment of specific cellular functions. In the postmitotic phase, osteopenia caused by the decrease of systemically available sexual hormones is a major field of research. Osteopenia caused by a decreased activity of locally effective cytokines and growth factors is becoming increasingly understood. New therapeutic strategies, which modulate the local osteoblast activity, e.g. in bone defect healing, are under development. In conclusion, cellular senescence is considered to be one element in the development of bone loss. Potential therapeutic targets may open up an additional path in the treatment of local and systemic osteopenias.

[Mediastinal Hodgkin lymphomas in computerized tomography. Comparison of exact CT-assisted volumetry and volume assessment using simple geometric models]. / Mediastinale Hodgkin-Lymphome in der Computertomographie. Vergleich von exakter CT-gestützter Volumetrie und Volumenabschätzung mit Hilfe einfacher geometrischer Modelle.

BACKGROUND: The importance of the size of the primary tumor in lymphomas and its size after treatment is still uncertain. Assuming a prognostic relevance, an assessment of tumor volume before and after induction of chemotherapy has been performed in the pediatric Hodgkin's disease study (HD-90). Since an exact CT-scan-based volumetric tumor assessment is time-consuming and in some centers not possible, the tumor volume is often estimated based on simple geometric approximations. Aim of this study was the development of an easy to apply and nearly exact model of volume estimation compared to CT-scan-based tumor volume measurements. MATERIAL AND METHODS: Thirty computed tomographies (CT) of mediastinal Hodgkin lymphomas of children aged 5 to 16 years have been examined. The CT scans were digitalized using a CCD camera combined with a frame grabber. Applying the Global Lab image software, the true tumor volume was determined excluding local organs, which did not belong to the lymphoma. Subsequently, volumes were assessed using simple geometric models (block, ellipsoid, octaeder) by using the maximum diameters of the tumor. The differences between the volume of the geometric models and the true volume, based on the CT scan evaluation, were compared. RESULTS: The maximum diameters of a tumor can be used to calculate its volume based on simple geometric models. The model "block" overestimates the volume by 89 to 268%. The model "ellipsoid" overestimates the volume on average by 29%. The model "octaeder" underestimates the volume on average by 18%. A division of the block volume by 2.3 approximated the geometric closest to the true volume: the average volume was overestimated by 2% in tumors with a volume larger than 20 ml. No model was sufficient to approximate tumors with a volume of less than 20 ml. CONCLUSIONS: For the estimation of tumor volumes in mediastinal Hodgkin lymphomas exceeding 20 ml, the formula "block/2.3" results in the closest approximation compared to the true volume. In the course of clinical studies it might be helpful to apply this formula to determine the prognostic relevance of the tumor size and its development under therapy.

MR hydrometry to assess exocrine function of the pancreas: initial results of noninvasive quantification of secretion.

PURPOSE: To evaluate magnetic resonance (MR) hydrometry, a method of quantifying fluid amounts by using MR imaging, for assessing the exocrine function of the pancreas after stimulation with secretin. MATERIALS AND METHODS: Images were obtained with a single-shot turbo spin-echo sequence by using a 1.0-T magnet with a quadrature body coil. Image postprocessing and evaluation were performed at an external workstation by using a specially designed histogram algorithm that translates the MR signal intensity of duodenal filling into an actual amount of duodenal fluid. This algorithm was tested in vitro and in vivo. Finally, MR hydrometry results in five patients were correlated with those of the secretin-cerulein test. RESULTS: The phantom measurements showed a high correlation (r = 0.99) between the actual amount of fluid in the imaging volume and the calculated results. In vivo, the ability of MR hydrometry to enable exact quantification of fluid amounts was demonstrated. In correlating the signal intensity of duodenal filling with the exact amount of additional fluid in the duodenum in volunteers, a coefficient of 0.043 gray tones per pixel per milliliter was calculated. The correlation (r) between secretin-stimulated duodenal fluid output estimated by using tube aspiration and that estimated by using MR hydrometry was 0.946 (P <.05). CONCLUSION: MR hydrometry is a promising noninvasive method of assessing fluid output as a measure of exocrine pancreatic function.

[Telepathology--applications of an emerging technology]. / Telepathologie--Anwendung einer entstehenden Technologie.

Due to the development of modern telecommunication by means of high speed data transfer either by normal telephone lines or the internet we are faced with new possibilities and chances in pathology. Instead of mailing slides, today images can be transferred electronically within seconds around the world, a second opinion of a highly skilled specialist can be available within the same day or even the same hour. Beside teleconsultation, telediagnostics is the most sophisticated application of telepathology. This means the evaluation of freshly prepared cryosections obtained during surgery by a pathologist using a remotely controlled microscope in a location deprived of pathological expertise. Since the technology applied has become very reliable, problems encountered by using this technology are mainly caused by either microscopic or macroscopic sampling errors. A correct diagnosis can not be obtained if the images mailed are not containing the necessary information. The same is true for telediagnostics, if the biopsy taken for cryosection does not contain the relevant lesion, a correct diagnosis will not be possible. However, these problems are not specific for telepathology, but are encountered in routinely processed specimens as well. Thus, protocols need to be developed assuring sufficient and reproducible image sampling for teleconsultation.

Sex steroids and bone metabolism: comparison of in vitro effects of 17beta-estradiol and testosterone on human osteosarcoma cell lines of various gender and differentiation.

Although numerous clinical studies have demonstrated the beneficial effect of preventing postmenopausal bone loss in elder women by long-term estrogen administration, effects of estrogen at the cellular level still remain unclear. Efforts to determine the precise role of bone cells in estrogen-mediated pathways are often hampered by the lack of suitable cell culture models. Presuming that sex steroids have a direct, stimulating effect on bone cells in vitro, we investigated the influence of 17beta-estradiol, testosterone and 1,25(OH)2D, on cell proliferation and differentiation using four established human osteosarcoma (HOS) cell lines of different gender of the donors (male origin: MG 63, HOS 58; female origin: SaOS 2, TE 85). These cell lines are believed to represent different stages of osteogenic maturation. Thus, the aim of this study was to clarify if possible responses to sex steroids are related to gender or osteogenic commitment of the individual cell culture. HOS cells were cultured in six-well plates and underwent hormone treatment (1 nM and 10 nM 17beta-estradiol. 0.1 nM and I nM testosterone and 1 microM 1,25(OH)2D3) for 48 h hours. Cell proliferation was determined by measuring total cell numbers. Cell function was studied by measuring alkaline phosphatase activity and secreted osteocalcin. In this study, estrogen significantly increased proliferation of both one male (MG 63) and one female (SaOS 2) cell line, but decreased proliferation of the female HOS TE 85 cell line significantly. Testosterone treatment had a positive effect on proliferation of only one female cell line (SaOS 2). A significant increase of alkaline phosphatase activity in SaOS 2 and HOS 58 cells and of osteocalcin levels in SaOS 2 cells was detected following estrogen treatment. Administration of 1.25(OH)2D3 was followed by an increased cell proliferation in HOS 58, MG 63 and SaOS 2. Significant gender-related differences could not be demonstrated. In conclusion, response to hormonal treatment with sex steroids is not related to the gender of the osteosarcoma cell line, but rather depends on its osteoblastic commitment.

Telemedicine: application of telepathology-remote microscopy for intraoperative diagnoses on frozen sections.

Due to the time delay, intraoperative consultations result in an extension of operation times, leading to prolonged anesthesia and idle time during surgery. Using a remote controlled microscope for telepathology, transfer times between hospital and pathologist can be eliminated and pathological expertise obtained independently of the geographic location of the hospital. In cooperation with a community hospital located 100 km apart from the Institute of Pathology of the Justus Liebig University Giessen, telepathological intraoperative consultations have been performed since 1999. After preparation and staining of the cryosection in the hospital, the slide was examined in our institute using a remote-controlled microscope (Leica DMRXA) and a special telepathological software (Leica TPS1). Data were transferred via two ISDN connections in parallel. The telepathology system contains an additional macroscopic examination equipment. Up to now more than 40 telepathological consultations have been done. Time required for the microscopic diagnosis ranged between 4 and 25 minutes. The amount of time saved, compared to the transfer to the next available pathologist, was approximately 45 minutes. In our experience, telepathological diagnoses were fully in accordance with conventional diagnoses routinely performed afterwards. The application of telepathology can lead to a significant shortening of surgery time if a pathologist is locally not available. In the study presented, no diagnostic errors occurred. The additional application of a macroscopic equipment allows inspection and interactive guidance for sampling, thus preventing sampling errors.

[Monitor assessment of digitalized and post-processed portal films compared to conventional films presented on a light box]. / Monitorbeurteilung digitalisierter und nachbearbeiteter Feldkontrollaufnahmen im Vergleich zu konventionellen Feldkontrollaufnahmen am Röntgenschaukasten.

PURPOSE: Judgement of image quality and detail recognition of digitized and post-processed portal films presented on a computer monitor compared to the present standard, conventional portal films presented on a light box. MATERIALS AND METHODS: Conventional portal films of 3 different tumor sites (10 pelvis, 10 cranium, 10 vertebral column) were presented to a panel of 8 observers in 3 different matters: conventional film presented on a light box (Conv), digitized post-processed images (Dig-1) and digitized post-processed images (Dig-2) presented on a high resolution computer monitor. Subjective judgement of image quality, detailed recognition and time requirement of conventional films compared to monitor presentation were evaluated using a 5-scaled questionnaire (from 1 = much better to 5 = much worse). Furthermore the observers had to point out predefined anatomical bony structure on the conventional films (Conv) as well as on the digitized post-processed images (Dig-2). Standard deviations of the landmark outlined by 10 different observers were used as a criterion of objective detail recognition (Figure 1). RESULTS: Image quality of digitized post-processed images presented on the computer monitor was judged statistical significant better than that of conventional films (pelvis 78%, vertebral column 62%, cranium 45% better) (Figure 3). Similar results were found for comparison of detail recognition: digitized post-processed images were scored better for pelvis in 81%, for vertebral column in 57%, for cranium in 40% (Figure 4, Table 1). Most benefit from portal film enhancement was found for pelvic images, where portal films are known to be of poor image quality (Figure 2). In contrast image quality of non-processed digital images compared to conventional films was graded worse (pelvis 69%, vertebral column 53%, cranium 71% worse) (Figure 4). Digital post-processed images were especially for the pelvis judged to require less time (pelvis 68%, vertebral column 26%, cranium 8% less time requirement) (figure 5). For the pelvis a statistical significant decrease of standard deviations was found for Dig-2 compared to conventional films, indicating an objective increase of image quality and detailed recognition (Table 2). In case of vertebral column and cranium no significant differences were evaluated (Table 3). CONCLUSIONS: Digitized enhanced portal films presented on a computer monitor resulted in a quicker assessment and equal to better image quality as well as detail recognition compared to conventional films. Non-processed digitized images were judged to be of less image quality.

[Bone matrix production in osteosarcoma]. / Knochenmatrixbildung in Osteosarkomen.

Osteosarcomas produce an extracellular matrix (ECM), called tumor osteoid, which is also the microscopic hallmark of these tumors. It can be difficult to differentiate tumor osteoid from other formations of ECM in intra-and extraskeletal soft tissue tumors, so that problems in differential diagnosis arise. Conventional special stainings provide a means to increase the reliability of the differential diagnosis, but do not identify the type of tumor conclusively as they only reflect physiochemical features and do not identify the molecular components of the matrix. The key to the solution of this problem is the immunohistochemical use of antibodies against bone matrix components. Matrix-immunohistochemistry using polyclonal and monoclonal antibodies against COL-I-C-peptide, Osteopontin, Osteonectin, Osteocalcin, and Decorin have proved to be a useful tool for the differentiation of osteoid in a series of 20 osteosarcomas with different variants of osteoid formation. For the detection of undifferentiated tumors, however, this method has not proved useful, since the cytoplasmatic immunoreactivity is variable. Molecular methods appear to be a more promising tool. Since the expression of Osteocalcin is known to be the last step of the osteoblastic differentiation, we have established a method to detect osteocalcin mRNA by RT-PCR. First studies of our group on the identification of the osteoblastic differentiation at the molecular level have revealed that Osteocalcin mRNA can be detected both in osteosarcoma cells and in non-skeletal tumor cell lines. In order to provide a reliable means of molecular tumor characterisation, thorough comparative studies on fresh and paraffin material of larger tumor series are in progress.

[Comparative genomic hybridization (CGH) for detecting a heretofore undescribed amplified chromosomal segment in high-grade medullary osteosarcoma]. / Komparative Genomische Hybridisierung (CGH) detektiert bisher nicht beschriebene amplifizierte chromosomale Abschnitte bei medullären High-Grade Osteosarkomen.

Osteosarcoma is one of the most commonly biopsied primary tumor of bone. High-grade osteosarcomas in particular exhibit a wide spectrum of cytogenetic changes. Molecular cytogenetic studies on osteosarcomas have shown that genomic amplification, especially of both the TP53-binding MDM2 gene and the flanking SAS gene, plays an important role in the biology of these tumors. We applied CGH in order to obtain a global view of DNA-sequence losses and gains in osteosarcoma. CGH was performed on 20 high-grade medullary osteosarcomas (13 primary tumors prior to chemotherapy, 5 tumors after chemotherapy, 2 established cell lines [MB63, HOS58]) using genomic DNA of snap-frozen tumor specimens. CGH revealed DNA copy number aberrations, mostly gains, in all the tumors studied with an average of 18.5 aberrations/tumor (range 8-32). High-level amplifications were observed in all cases (average 4.1 amplifications/tumor [range 1-10]). Amplicons affecting at least five tumors were mapped to 1p21-31 (9/20 cases), 3q25-qter (6/20), 6p12-21 (6/20), 8q12-qter (10/20), 12p11-12 (9/20), 12q12-15 (enclosing MDM2 and SAS loci, 7/20). Losses were most frequently seen at 3p, 10q, 11p and 13 (all 10/20). In conclusion, our CGH data indicated that genomic amplification plays an important role in the biology of osteosarcoma. CGH demonstrated the complexity of genetic aberrations in osteosarcomas. The detection of novel non-random DNA amplifications in our study has defined regions for further targeted molecular genetic research aimed at identifying those oncogenes that are characteristic of osteosarcoma development.

Endosteal human bone cells (EBC) show age-related activity in vitro.

Based on the hypothesis that decreasing osteoblastic function is one of the reasons for the development of osteoporosis, we have studied the proliferation and protein production of isolated bone cells of young and old human donors. The isolation procedure for bone cells is based on a combined mechanical and enzymatical treatment of human trabecular bone. Endosteal bone cells (EBC) obtained by this method developed typical osteoblast-like characteristics in culture. The most important functional feature was the dose-dependent increase of osteocalcin production following stimulation with 1.25(OH)2D3. Growth of EBC (measured as emigration time after plating of trabecular bone fragments) was equal in premenopausal women and men aged under 40 years, but was impaired in EBC of men aged over 50 years. The production of osteocalcin after stimulation with 1.25(OH)2D3 was about 60% lower in older donors (> 50 years) than in younger ones (< 40 years), regardless of gender. According to our results osteoblastic function is reduced with increasing age in human EBC of both genders as clearly shown by a diminished protein production. However, the anticipated depressive effect of age on growth of bone cells was obvious in males only. So called age related osteoblastic insufficiency does exist but it has to be considered differently for bone cell function and bone cell growth. The limited data shown in this study should enhance understanding of age and sex related changes in the EBC metabolism.

Serum fluoride and serum osteocalcin levels in response to a novel sustained-release monofluorophosphate preparation: comparison with plain monofluorophosphate.

In a previous study we found that sustained-release monofluorophosphate (MFP-SR), a novel, sustained-release MFP preparation, acutely maintained the basal therapeutic serum fluoride levels without causing the high serum peak levels associated with plain MFP administration. The objective of the present study was to determine (a) whether chronic MFP-SR administration would provide therapeutic serum fluoride levels, and (b) whether treatment with this new preparation would result in an increase in bone formation similar to that achieved with plain MFP. Bone formation was assessed by serum osteocalcin (OC) determination. We studied 17 postmenopausal women older than 60 years and suffering from primary osteoporosis. All had received a minimum of 6 months of continuous treatment with plain MFP at a dose of 152 mg/day (76 mg b.i.d.). Upon entering the study, the subjects were randomized, in a double-masked protocol, to receive either MFP-SR (76 mg b.i.d.) (n = 9) or placebo (n = 8) for 2 months, after which all subjects returned to the original plain MFP regimen. Serum fluoride and serum OC levels were determined monthly for 3 months. At the beginning of the study serum fluoride levels were in the accepted therapeutic range (5-10 microM) in all patients. Serum fluoride levels were maintained in the patients switched to MFP-SR. In contrast, serum fluoride levels decreased significantly (p < 0.005) in the placebo-treated control subjects and returned to therapeutic levels upon switching back to plain MFP. Similarly, serum OC levels remained elevated in the subjects switched to MFP-SR but dropped significantly (p < 0.001) in the placebo-treated group. Our results demonstrate that chronic MFP-SR administration, at a dose of 152 mg/day, results in maintenance of therapeutic serum fluoride levels and in stimulation of bone formation. Because we have previously reported that high, supratherapeutic post-absorptive serum fluoride levels are avoided by MFP-SR administration, this novel preparation may prevent side effects associated with plain MFP by reducing the amount of fluoride deposited in bone.

Risk of vertebral fractures in men: relationship to mineral density of the vertebral body.

OBJECTIVE: Vertebral fracture is the most frequent manifestation of osteoporosis in women. Because there is a lack of information about bone density and the occurrence of fractures in men with osteoporosis, we evaluated the relationship between vertebral fractures and spinal bone mineral density (BMD) to determine if there is a threshold of BMD below which fractures are likely to occur. SUBJECTS AND METHODS: Radiographs of the spine and BMD measurements of the lumbar spine as measured by quantitative CT were obtained in 201 men 21-86 years old (mean age, 68 +/- 4 years) who were referred consecutively for osteoporosis screening. Radiographs were interpreted for the presence or absence of vertebral fractures. The probability of fractures was determined after classifying the patients into subgroups according to their quantitative CT values. The relationship of spinal bone mass to spinal fracture was examined by both logistic regression and receiver operating characteristic (ROC) analysis. RESULTS: Seventy-one patients were classified as having definite vertebral compression fractures. Spinal BMD was 132 +/- 34 mg/ml for the 130 men without vertebral fractures and 75 +/- 22 mg/ml for the 71 men with vertebral fractures (p < .001). The number of fractures per patient and the BMD were negatively correlated (r = -0.71, p < 0.0001). When a BMD of 100 mg/ml was given as a fracture threshold, 15% of the patients without fractures were below this value and 14% of the patients with fractures were above this threshold. Quantifying the overlap between values from patients with and without fractures by ROC analysis, the value of 100 mg/ml gave a sensitivity of 86%. Logistic regression showed 105 mg/ml as the most discriminate value, resulting in a sensitivity of 90%. Logistic regression analysis of the predicted fracture probability also indicated that age does not significantly influence the regression curve. CONCLUSION: We found that direct quantitative CT measurement of the BMD of the vertebral body is a highly efficient approach to distinguish men without vertebral fractures from those with fractures. Thus, a fracture-threshold concept could provide a quantitative criterion to identify men at high risk for vertebral fractures.

Unusual differentiation of a combination tumor of the parotid gland. A case report.

A 67-year-old female patient developed a slowly growing swelling in the region of the left mandibular angle. This swelling was tender on pressure. Clinical examinations revealed an immobile, circumscribed, palpable node. Sonography showed an inhomogeneous space-occupying mass with a predominantly poor echo in the cranial and dorsal parts of the parotid gland. Intraoperatively the lesion presented as a smooth-bordered, round, capsulated tumor, which was excised "in toto". The postoperative course was uneventful. Histologic examination revealed a salivary gland tumor consisting of two components. Glandular structures corresponding to a Warthin tumor were seen in the center, whereas differentiation in the periphery of the tumor was that of a sebaceous lymphadenoma. Metaplastic sebaceous glands within salivary glands have been occasionally described, but true sebaceous lymphadenomas of the salivary glands are a rarity. A rare variant of Warthin's tumor is its metaplastic type, in which extensive metaplasia of the squamous epithelium is observed. The morphologic parallels as well as the differences seen in our case are described. We believe that it does not meet the criteria of a metaplastic Warthin tumor and have therefore diagnosed a combination tumor of the parotid gland, which is composed of a Warthin tumor component and a sebaceous lymphadenoma component.