Inducible nonviral gene expression in the treatment of osteochondral defects

OBJECTIVE

The repair of osteochondral defects with chondrocytes genetically modified to express desired growth factors promises great potential in orthopaedic therapy. Controlled expression of the transgenes is required in many instances. The objective of the present study was to demonstrate the inducibility of tetracycline-responsive transgene expression in osteochondral defects in the knee joint filled with genetically modified chondrocyte implants.

METHODS

An expression plasmid containing the lacZ gene under the control of the minimal CMV promoter fused to the Tet-responsible element (TRE) as well as the reverse transactivator (rtTA2s-M2) was constructed and used to transfect isolated articular chondrocytes from New Zealand white rabbits. rtTA2s-M2 binds to the TRE in the presence of tetracycline and leads to the transcription of the transgene. Different concentrations of DNA and various DNA:lipid ratios were tested to determine best transfection conditions. Transfection efficiency and inducibility were analysed by histochemical analysis and flow-cytometry. To evaluate the system in vivo, collagen-sponges were seeded with transfected autologous chondrocytes and implanted in osteochondral defects in the knees of NZW-rabbits. Gene expression was induced by doxycycline and 3 weeks later, LacZ-expression in isolated knee joints was evaluated in histological sections by X-gal staining.

RESULTS

In vitro 13.5% (+/-1.32) of induced primary chondrocytes were LacZ-positive, while non-induced controls showed a background-staining in 0.6% (+/-0.2). In vivo, upon doxycycline treatment, induction of lacZ-gene-expression could be demonstrated in chondrocytes in 3-week-old, well-integrated implants.

CONCLUSION

For the first time, tetracycline-inducible gene expression is demonstrated to work in the treatment of osteochondral defects. This demonstrates the feasibility for a gene therapy-assisted approach using controlled expression of therapeutic growth factors from transplanted genetically modified chondrocytes.

Identification of premycorrhiza-related plant genes in the association between Quercus robur and Piloderma croceum

•  An in vitro system with micropropagated oaks (Quercus robur) and the ectomycorrhizal fungus Piloderma croceum, which is characterized by a delayed mycorrhiza formation, was used to identify plant transcripts upregulated in the premycorrhizal phase. •  Complementary DNA (cDNA) populations of uninoculated roots and fungal mycelium were subtracted from a cDNA population of inoculated roots. Differential expression was confirmed by reverse Northern and 50 clones for different polypeptides were found to be up-regulated. Twenty-nine clones were investigated in more detail. •  For approximately half of the cDNA fragments no homologies could be identified in databases. The residual fragments code for polypeptides with homologies to known proteins involved in signal perception and transmission, stress responses, metabolism and growth. •  Since many of the identified genes have not yet been described in the context of symbiotic events, their potential roles during early phases of the recognition process are discussed.

Two new cytoforms of the Simulium damnosum complex (Diptera: Simuliidae) from Malawi and Tanzania and potential onchocerciasis vectors

During a distribution survey of Simulium damnosum s.l. around the Tukuyu onchocerciasis focus at the northern tip of Lake Malawi/Nyasa (Tanzania), we discovered two new cytoforms of the S. damnosum complex in onchocerciasis-free areas. The Nyika form is related to Simulium thyolense, a vector of onchocerciasis, and can be identified by the new inversion 3L-L on the long arm of chromosome 3. It was found breeding in five rivers in northern Malawi and neighbouring Tanzania and is assumed to be zoophilic. The Njombe form represents a member of the Sanje group of the complex and is characterized by the new diagnostic inversion 2L-35 on chromosome 2. So far, it is only known from around Njombe town in southern Tanzania, where it breeds at remarkably high altitudes. Anthropophily for the Njombe form is well known. The medical importance and systematic position of the new forms within the S. damnosum complex are discussed.

Erste Ergebnisse ventraler versus dorsaler Instrumentation nach Ausräumung und intervertebraler Fusion bei Spondylodiszitis

AIM

The present study on spondylodiscitis patients was carried out to compare prospectively and randomized the results of clinical and radiological outcomes of anterior versus posterior instrumentation after debridement and grafting. We aimed to make a recommendation concerning the optimum treatment of spondylodiscitis.

METHOD

A total of 22 patients with spondylodiscitis were enrolled in the randomized trial to undergo an operation with anterior or posterior instrumentation after debridement and fusion with autologous bone transplant. 12 patients (group 1) were assigned to posterior Universal Spine System stabilization. 10 patients (group 2) were treated with anterior VentroFix instrumentation. In a prospective clinical investigation we have examined both operative therapies with regard to clinical and radiological outcome. The follow-up was one year.

RESULTS

In patients with ventral Spondylodesis (group 2), prior recreation of patients was achieved in clinical examination and blood tests. Radiological results are even equivalent in both groups. Therefore we recommend ventral instrumentation as the superior surgical procedure. But the individual local situation has to enable ventral stabilization.

CONCLUSION

We found advantages with anterior instrumentation in comparison to posterior stabilization in patients with spondylodiscitis. Advantages of ventral stabilization cause early mobilization postoperatively without any increase in complication rates. Except for operation time and intraoperative blood loss, no statistical difference were was seen. Important is the individual indication for each method depending on anatomical and clinical signs. Ventral instrumentation should be restricted to cases with sufficient bone stock.

Influence of antibiotic prophylaxis on perioperative risk in traumatology with the new concept of clinic modelling randomized trials in animals

Background

Surgical outcome depends not only on different therapies, but also on different additionally applied measures like prophylaxis (antibiotics, heparin, etc.) and their complex interaction. The aim of this study was to establish a new concept of clinic modelling randomized trials (CMRTs) in rats (haemorrhagic shock model) to investigate the harmful or beneficial effects of antibiotic prophylaxis in trauma patients (evidence-based medicine). Elements of the clinical scenario and methodology of randomized trials were modelled as accurately as possible in this CMRT.

Methods

Conditions of the rat model (CMRT) were adapted to the methodology of clinical trials and the clinical scenario with respect to sample size calculation, blinding and randomized allocation in a two-block design (n = 20 animals per group), anaesthesia with fentanyl–droperidol, standardized operation (soft tissue damage, tibia fracture and nailing), antibiotic prophylaxis 1 h before operation (intravenous cefuroxime 20 mg kg−1 versus placebo (sodium chloride)), volume substitution (Ringer) and postoperative analgesia. The clinical situation of healthy (American Society of Anesthesiologists (ASA) grade I and II) and severely injured (ASA III and IV) patients was simulated in the CMRT by sham operation and preoperative blood-letting, respectively, to initiate a relevant shock (1·5 h of mean arterial pressure 50 mmHg, blood pressure measured in the femoral artery). The shock period was followed by resuscitation (volume loading) with Ringer solution 40 ml kg−1. The endpoint was the 21-day mortality rate. Fracture healing was documented by radiography.

Results

The animal model was established successfully. The required blood-letting for relevant shock was 20 ml kg−1. The mortality rate in animals without blood-letting simulating healthy patients (ASA I and II) was zero in the cefuroxime and in placebo groups (n = 20 per group). In the experiment with preoperative blood-letting (ASA III and IV, n = 20 per group) a clear but not significant trend in the mortality rate for the cefuroxime group (20 per cent) versus placebo (40 per cent) could be observed (1 d.f., P > 0·05, χ2 test). Disturbances of fracture healing did not occur.

Conclusion

The clinical impact (evidence based) of antibiotic prophylaxis in traumatology was demonstrated in these experiments. The influence of other currently used antibiotics in trauma patients could be investigated in such animal models (CMRTs) instead of expensive and time-consuming clinical trials. The results of this study suggest the advantage of prophylaxis with cefuroxime in severely injured patients. Other antibiotics and the pathophysiological mechanisms will be investigated in further studies.

[Epulis in a newborn. histogenetic comparison with a granular cell tumor in adults]

The congenital granular cell tumor is a rare lesion of newborns located on the alveolar ridge with a marked predilection for female infants. Histologically these tumors are characterized by large eosinophilic granular cells, similar to granular cell tumors in adults which are often seen as Abrikossoff tumors. Immunohistochemical studies revealed the different histogenesis and evolution of both these tumor entities. We report on a female newborn infant with a congenital epulis of the left anterior maxillary alveolar ridge. This case demonstrates a rare congenital tumor of newborns and reveals the histogenetic differences to granular cell tumors in adults.

Magnetofection: enhancing and targeting gene delivery by magnetic force in vitro and in vivo

Low efficiencies of nonviral gene vectors, the receptor-dependent host tropism of adenoviral or low titers of retroviral vectors limit their utility in gene therapy. To overcome these deficiencies, we associated gene vectors with superparamagnetic nanoparticles and targeted gene delivery by application of a magnetic field. This potentiated the efficacy of any vector up to several hundred-fold, allowed reduction of the duration of gene delivery to minutes, extended the host tropism of adenoviral vectors to nonpermissive cells and compensated for low retroviral titer. More importantly, the high transduction efficiency observed in vitro was reproduced in vivo with magnetic field-guided local transfection in the gastrointestinal tract and in blood vessels. Magnetofection provides a novel tool for high throughput gene screening in vitro and can help to overcome fundamental limitations to gene therapy in vivo.

Two cases of autochthonous Plasmodium falciparum malaria in Germany with evidence for local transmission by indigenous Anopheles plumbeus

Autochthonous Plasmodium falciparum malaria (PFM) in Central Europe has been reported repeatedly, transmission of the parasite being attributed to blood transfusion or imported P. falciparum-infected vectors. We report two cases of PFM in German children without travel history to malaria-endemic areas. Both infections occurred during a stay in a hospital where a child from Angola with chronic P. falciparum infection was hospitalized at the time. Known routes of transmission, such as imported mosquitoes or blood transfusion, were very unlikely or could be excluded, whereas evidence was obtained for transmission by the indigenous mosquito species Anopheles plumbeus.

Synthesis of cyclo-1,3-dien-5-ynes

Cyclo-1,3-dien-5-ynes with ring sizes from 10 to 14 (6a-e) have been prepared for the first time by using a five-step synthesis starting from the alkynols 7a-e. The final ring-closure was achieved by McMurry coupling of the alpha,omega-dialdehydes 12a-e with the complex TiCl3(DME)1.5. Thermal isomerization of the cyclodienynes leads to the corresponding benzocycloalkenes, and it has been shown that the ring size has a considerable influence on the temperature necessary for thermocylization.

Procalcitonin following elective partial liver resection--origin from the liver?

BACKGROUND

The origin of the inflammatory peptide procalcitonin (PCT) is still unknown. In the present study PCT concentrations in arterial and hepatic-venous blood were examined in patients undergoing elective partial liver resection (LR) using a fiberoptic pulmonary arterial catheter placed in a liver vein to obtain further information on the origin of PCT.

METHODS

In 28 patients (21 male/7 female; average age of 58.8+/-8.8 years) undergoing LR, arterial and hepatic venous PCT concentrations were measured during 24 h perioperatively. The parallel blood withdrawals occurred immediately before the Pringle maneuver (Hx), 2 min, 1, 2, 6, 12, and 24 h after Hx. Over the whole period, the oxygen saturation in hepatic venous blood (ShvO2) was monitored. PCT concentrations were assayed by immunoluminometry.

RESULTS

We observed a significant increase in PCT concentration already 6 h after Hx compared to the values before Hx. Twenty-four hours after Hx we found the highest plasma concentrations. It was conspicuous that hepatic venous PCT concentrations were always higher than the arterial ones (significantly from the 6th hour after Hx). There was no correlation between the courses of ShvO2 and PCT rise. A significant correlation was verified between Hx duration and PCT concentration measured 24 h after Hx both in the hepatic venous and arterial blood.

CONCLUSIONS

The results of our investigation can be interpreted as evidence that liver (or the hepatosplanchnicus?) is a source of PCT. The mechanism of PCT induction cannot be clarified by our study: whether the induction of PCT was caused by an endotoxin translocation during the impeded splanchnic outflow or by the direct surgery-induced lesion (hypoxia) of the liver remains unclear. However, the latter appears more probable because of the observed correlation between Hx duration and PCT concentration rise.

Alagille syndrome associated with a paracentric inversion 20p12.2p13 disrupting the JAG1 gene

Mutations in the human gene Jagged1 (JAG1) localized in 20p12 have been recently identified as causal for the anomalies found in patients with Alagille syndrome (AGS). This gene encodes a ligand for the Notch1 transmembrane receptor, which plays a key role in cell-to-cell signaling during differentiation and is conserved from C. elegans to human. We report a paracentric inversion (PAI) of chromosome 20p12.2p13 in an individual with AGS who also had alpha-1-antitrypsin deficiency. To our knowledge, this is the first published case of PAI involving the short arm of chromosome 20. Using FISH, fiberFISH, and molecular studies with a approximately 40 kb cosmid clone encompassing the entire 36 kb JAG1 gene, we demonstrate that the gene was disrupted by the inversion breakpoint between exons 5 and 6. An unusual association between two most common causes of chronic liver disease in childhood, AGS and alpha-1-antitrypsin deficiency, as well as their influence on the proband's abnormal phenotype are discussed.

Phenotypic findings due to trisomy 7p15.3-pter including the TWIST locus

We report on a three-month-old boy with a 46,XY,der(Y)t(Y;7)(p11.32;p15.3) karyotype and growth deficiency, postnatal microcephaly with large fontanels, wide sagittal and metopic sutures, hypertelorism, choanal stenosis, micrognathia, bilateral cryptorchidism, hypospadias, abnormal fingers and toes, and severe developmental delay. FISH studies showed partial trisomy 7p resulting from a de novo unbalanced translocation. The application of molecular probes from the TWIST gene region (7p15.3-p21.1) and probes from the pseudoautosomal region (PAR) demonstrated that the 7p15.3-pter fragment was translocated onto Yp with the breakpoint within approximately 20 kb from the Yp telomere. We discuss the possible role of the TWIST gene in abnormal skull development and suggest that trisomy 7p cases with delayed closure of fontanels can be a result of TWIST gene dosage effect.

Prognostic impact of proteolytic factors (urokinase-type plasminogen activator, plasminogen activator inhibitor 1, and cathepsins B, D, and L) in primary breast cancer reflects effects of adjuvant systemic therapy

PURPOSE

Prognostic and predictive impact of five proteolytic factors associated with tumor invasion and metastasis in primary breast cancer were evaluated after long-term follow-up.

EXPERIMENTAL DESIGN

Antigen levels of urokinase-type plasminogen activator, plasminogen activator inhibitor-1 (PAI-1), Cathepsins B, D, and L were determined using immunochemical assays in primary tumor tissue of 276 patients.

RESULTS

During follow-up (median 109 months), 119 (43%) patients relapsed, and 117 (42%) died. In the whole collective, lymph node status (P < 0.001; RR 3.8), Cathepsin L (P < 0.001; RR 2.6), and PAI-1 (P = 0.027; RR 1.7) were the only independent significant factors in multivariate analysis for disease-free survival (DFS). For overall survival (OS), lymph node status (P < 0.001; RR 2.9), Cathepsin L (P = 0.017; RR 1.9), PAI-1 (P = 0.01; RR 1.9), and grading (P = 0.026; RR 1.7) were significant. In the node-negative subgroup, PAI-1 was the only significant factor for DFS (P = 0.004; RR 3.7) and the strongest factor (P = 0.004; RR 3.7) for OS next to grading (P = 0.017; RR 3.1). In node-positive patients, Cathepsin L was the only significant factor for both DFS (P < 0.001; RR 3.2) and OS (P = 0.003; RR 2.5). For all proteolytic factors but Cathepsin L, the univariate prognostic impact on DFS was substantial in patients without adjuvant systemic therapy but was diminished if adjuvant therapy had been administered. Cathepsin L maintained its strong prognostic impact on DFS even in patients with adjuvant endocrine therapy (P = 0.01; RR 2.8).

CONCLUSIONS

The observed effect of adjuvant systemic therapy on their prognostic strength suggests that the assessed proteolytic factors supply predictive information on therapy response.

Kabuki syndrome-like features associated with a small ring chromosome X and XIST gene expression

Although clinical features in Kabuki syndrome (KS; Niikawa-Kuroki syndrome) have been well defined, the underlying genetic mechanism still remains unclear. We report a 9-year-old girl with typical KS-like facial appearance, skeletal and dermatoglyphic abnormalities, severe mental retardation, and growth deficiency. In 60 of 100 GTG-banded metaphases from peripheral blood lymphocytes, a ring chromosome smaller than a G group chromosome was found, which, according to reverse painting, consisted of Xq11.1q13. The proband's karyotype was described as mos45,X/46,X,+r(X). Several loci were analyzed with fluorescence in situ hybridization (FISH) and microsatellite markers revealing that one r(X) breakpoint mapped proximal to DXS422 (Xp11.21) and the second mapped distal to XIST gene, between loci DXS128E and DXS441 (Xq13.2). Uniparental disomy for X and r(X) was excluded and the paternal origin of r(X) was identified. XIST expression was demonstrated by nested reverse transcription polymerase chain reaction (RT-PCR) using primers spanning exons 5, 6i, and 6 in RNA prepared from lymphocytes. The observation of XIST expression is in contrast to two other cases in which the XIST gene was either not present on r(X) or not expressed. To our knowledge, this is the first case of Kabuki-like syndrome manifestations with r(X) and XIST expression.

Clinical relevance of the plasminogen activator inhibitor type 1--a multifaceted proteolytic factor

The plasminogen activator inhibitor type-1 (PAI-1) is a multifaceted proteolytic factor. It not only functions as an inhibitor of the protease uPA (urokinase-type plasminogen activator), but also plays an important role in signal transduction, cell adherence, and cell migration. Thus--an apparent paradox considering its name--although it inhibits uPA during blood coagulation, it actually promotes invasion and metastasis. In the early 1990s, clinical evidence associated elevated PAI-1 levels in tumor tissue with poor clinical outcome in primary breast cancer. These clinical data have since been supported by experimental evidence that the concerted action of uPA, its cell surface receptor uPA-R, and PAI-1 facilitates invasion and metastasis. The strong prognostic impact of PAI-1 in primary breast cancer has been validated by international research groups assessing fresh tumor tissue extracts by ELISA. There is clinical evidence that high-risk patients with elevated PAI-1 in their tumor benefit from adjuvant systemic therapy. uPA also has a strong prognostic impact in primary breast cancer. In node-negative breast cancer, risk-group selection for adjuvant systemic therapy based on tumor levels of both PAI-1 and uPA is close to routine clinical use. Also in other malignancies such as ovarian, esophageal, gastric, colorectal or hepatocellular cancer, elevated PAI-1 is associated with tumor aggressiveness and poor patient outcome. This abundant clinical evidence implicating PAI-1 as a key factor for tumor invasion and metastasis renders it a promising target for tumor therapy. Novel therapeutic approaches targeting the PAI-1/uPA interaction are already in pre-clinical testing.

High level synthesis of recombinant soluble urokinase receptor (CD87) by ovarian cancer cells reduces intraperitoneal tumor growth and spread in nude mice

Focussing of the serine protease urokinase (uPA) to the tumor cell surface via interaction with its receptor (uPAR) is an important step in tumor invasion and metastasis. The human ovarian cancer cell line OV-MZ-6#8 was stably transfected with expression plasmids either encoding cell-associated uPAR (GPI-uPAR) or a soluble form of uPAR (suPAR) lacking its glycan lipid anchor. In vitro, high level synthesis of functionally active recombinant suPAR inhibited cell proliferation and led to reduced cell-associated fibrin matrix degradation, whereas fibrinolytic activity was increased in OV-MZ-6#8 cells overexpressing GPI-uPAR. Both OV-MZ-6#8-derived clones were inoculated into the peritoneum of nude mice and tested for tumor growth and spread. High level synthesis of recombinant suPAR (without altering the physiological expression levels of GPI-uPAR and uPA in these cells) resulted in a significant reduction of tumor burden (up to 86%) in the xenogeneic mouse model. In contrast, overexpression of GPI-uPAR in tumor cells did not affect tumor growth. Our results demonstrate that high levels of suPAR in the ovarian cancer cell vicinity can act as a potent scavenger for uPA, thereby significantly reducing tumor cell growth and cancer progression in vivo.

Pressure distribution measurements in wheelchair use

There is a growing number of mobility-impaired and wheelchair-dependent patients caused by diseases and injuries of the central nervous system. The risk is high for pressure sores to develop due to disturbances of the motor, sensory, and autonomic nervous system. Numerous seating systems for prophylaxis and treatment of decubitus ulcer are available. To identify risk parameters, the literature on animal experiments regarding pressure ulcers was reviewed. A study on the reproducibility of the analysis method with capacitive sensors tested in ten paraplegics with 470 measurements is presented. It shows the reliability of the procedure.

Hydroxamate-type matrix metalloproteinase inhibitor batimastat promotes liver metastasis

Overexpression of matrix metalloproteinases (MMPs) facilitates tumor cell invasion. Synthetic MMP inhibitors such as batimastat have been designed to treat cancer. We report that because of batimastat treatment, human breast carcinoma cells metastasized to the liver in nude mice and that an increase of liver metastases of murine T-cell lymphoma cells was observed in syngeneic mice. Batimastat treatment also caused liver-specific overexpression of MMPs-2, -9, and mRNA up-regulation of angiogenesis factors and caspase-1, even in tumor-free animals. Induction of organ-specific side effects need to be taken into account regarding further development and clinical use of synthetic MMP inhibitors.

A new protein expressed in bone marrow cells and osteoblasts with implication in osteoblast recruitment

To study osteoblast recruitment from bone marrow cells, a rat femur cDNA library was screened by in situ hybridization for novel mRNA sequences that are frequently expressed in both marrow cells and osteoblasts. One isolated clone, called RP59, is described here. Northern blots indicated two bands of 2.6 and 2.8 kb in femur and spleen, tissues containing high amounts of immature mesenchymal cells, and no or little expression in other tissues. The cDNA sequence revealed a reading frame for a repetitive protein composed of arrays of 14-mers and phased phosphorylation sites. Antisera versus RP59 detected a single band of 90 kDa by Western blotting of femur extract. Immunohistochemistry indicated strong RP59 presence in the cytoplasm of bone marrow cells and weaker presence in nuclei of osteoblasts. Intermediate stages were found between strongly labeled, round, free bone marrow cells and weaker labeled, fibroblast-like young osteoblasts associated with bone matrix. These data indicated that marrow cells with high RP59 content were recruited into growing bone tissue. RP59 may help to study the transition of bone marrow cell to osteoblast in more detail.

Reactive bone marrow changes in infectious spondylitis: quantitative assessment with MR imaging

PURPOSE

To evaluate diffuse, reactive bone marrow changes in unaffected vertebrae on magnetic resonance (MR) images in patients with proved infectious spondylitis.

MATERIALS AND METHODS

Percentage signal intensity increase of the unaffected bone marrow on contrast material-enhanced MR images (percentage enhancement) was calculated retrospectively in 22 cases of infectious spondylitis and 86 cases without bone marrow disease. Multiple regression analysis and Student t test statistics were performed.

RESULTS

Multiple regression analysis showed a significant influence of age and the presence of spondylitis on the values of percentage enhancement (P: <.001). For those aged 35 years or younger, the mean percentage enhancement was 43.2% +/- 4.0 for patients with infectious spondylitis (n = 3) and was 26.4% +/- 8.6 for the control group (n = 23). For those older than 35 years, the mean percentage enhancement was 28.2% +/- 12.2 for patients with infectious spondylitis (n = 19) and 17.5% +/- 7.9 (P: <.001) for the control group (n = 63). Six (27%) of 22 patients with infectious spondylitis showed abnormal percentage enhancement values in unaffected bone marrow when the upper limit of the normal value was 2 SDs above the mean of the control group.

CONCLUSION

On MR images, reactive bone marrow changes can be found in unaffected vertebrae in patients with infectious spondylitis. The signal intensity changes and increased percentage enhancement associated with this disease are similar to those of myeloproliferative and diffuse neoplastic disorders and bone marrow stimulation in hemolytic anemia.

Tripled semitendinosus anterior cruciate ligament reconstruction with Endobutton fixation: a 2-3-year follow-up study of 35 patients

We evaluated the clinical outcome of tripled semitendinosus tendon ACL reconstruction with femoral Endobutton (Acufex, Smith&Nephew, Andover, MA) and tibial Suture Washer (Acufex, Smith&Nephew, Andover, MA) (n 29) or post screw fixation (n 6) in 35 patients on an average of 28 (20-37) months after surgery. On the basis of IKDC criteria, 22 patients showed a normal or nearly normal knee function and 25 patients had a KT 1000 maximal manual side-to-side difference of < or =5 mm at follow-up. Subjectively, 28 patients graded their knee function as normal or nearly normal. The average Lysholm score was 88 points, average OAK score 90 points and average modified HSS score 93 points. 19 patients reached their preinjury level of activity at follow-up. The postoperative Lachman test was < or =1+ in 24 patients and 24 patients also showed an absent pivot shift. Significant bone tunnel enlargement occurred in 26 patients on the femoral side and in 23 patients on the tibial side. We found no correlation between bone tunnel enlargement and clinical outcome. The clinical outcome of tripled semitendinosus tendon ACL reconstruction with Endobutton fixation on the femoral side was not entirely satisfactory. The procedure was associated with a high incidence of bone tunnel enlargement in this series.

Chemical and biochemical composition of caviar from different sturgeon species and origins

The chemical and biochemical composition of caviar in 22 specimens of wild caught and of 2 farmed animals were measured. The results include grain size, protein and fat content, fatty acid composition of triglycerides and phospholipids, as well as the concentrations of relevant heavy metals and chlorinated hydrocarbons. The average protein content varied between 26.2 and 31.1% (wet weight) and fat from 10.9 to 19.4% (wet weight) with lowest values for caviar from farmed sturgeon. The triglycerides and phospholipids contained more n-3 fatty acids, especially eicosapentaenoic and docosahexaenoic acid than n-6 fatty acids. The copper and zinc concentrations varied between 1.20 and 1.69 and 10.3 and 12.4 mg/kg (wet weight), respectively. These values reflect the elevated requirement of sturgeons for these components. Lead content varied between 0.06 and 0.15 mg/kg (wet weight). The cadmium concentrations were less than 5 micrograms/kg (wet weight) leading to the conclusion that no accumulation took place in the eggs. The concentrations of sigma DDT and sigma PCB were extremely high in caviar from Huso huso compared to the samples of the other species thus reflecting the different food habits leading to increased bio-accumulation.

The cytotaxonomy of Simulium damnosum s.l. (Diptera: Simuliidae) from the Thyolo onchocerciasis focus in Malawi and description of a new member of the complex

Larvae of the Simulium damnosum complex were collected in southern Malawi, in particular from the Thyolo onchocerciasis focus. Cytological identifications revealed the occurrence of S. (Edwardsellum) thyolense sp.nov., S. kilibanum Gouteux, 'Ketaketa', a new cytoform tentatively designated 'Mwamphanzi', and two unassigned specimens. Simulium thyolense sp.nov. is presumably the major vector of Onchocerca volvulus in the area, but it remains possible that the other cytospecies are secondary vectors. Simulium thyolense sp.nov. is most appropriately classified near the 'Sanje' subcomplex, whereas 'Mwamphanzi' and the unassigned specimens are members of the 'Ketaketa' subcomplex.

Reduction of breast carcinoma tumor growth and lung colonization by overexpression of the soluble urokinase-type plasminogen activator receptor (CD87)

The serine protease urokinase-type plasminogen activator, uPA, when bound to its specific receptor, uPAR (CD87), plays a significant role in tumor cell invasion and metastasis. In breast cancer, enhanced uPA antigen in the primary tumor is correlated with poor prognosis of the patient. In an in vivo nude mouse model, we tested tumor growth and metastasis of human breast carcinoma cells that had been transfected with an expression plasmid encoding a soluble form of uPAR (suPAR). We explored, whether suPAR/uPA interaction reduces the binding of uPA to cell surface-associated uPAR, and, as a consequence, could suppress tumor growth and metastasis of the human breast cancer cell line MDA-MB-231 BAG. Overexpressed, secreted suPAR was shown to bind and thus scavenge the uPA secreted by the transfected lines suPAR3 and suPAR10. In vitro, an overexpression of suPAR did not alter the proliferation rate of the transfected tumor cells, nor did it affect the expression of uPA. Overexpression of suPAR led to a reduction in the plasminogen activation-related proteolytic activity of breast carcinoma cells. Primary tumor growth in the mammary fat pad of nude mice was followed up for 52 days. Overexpression of suPAR correlated with a reduction in tumor growth (from day 21, reaching 30% by day 34) as well as lung colonization (lung metastasis-positive mice in suPAR3: 4 of 17; suPAR10: 3 of 10; parental MDA-MB-231 BAG: 13 of 18). We conclude that suPAR overexpression leading to effective scavenge of uPA impairs proteolysis as well as the tumor growth and metastatic potential of breast carcinoma cells in vivo.

Molecular identification and phylogeny of East African Simulium damnosum s.l. and their relationship with west african species of the complex (Diptera: Simuliidae)

The phylogenetic relationships of East and West African members of the Simulium damnosum complex were studied by sequence analyses of the mitochondrial 16s ribosomal RNA (rRNA) gene. Results suggest that: (i) the S. damnosum complex is divided into an East and a West African clade, and (ii) S. pandanophilum and the cytoform 'Kiwira' form an East African subbranch distinct from the 'Sanje' group. In contrast to former assumptions from cytogenetic analyses, our molecular data do not support a direct relationship between the East African S. kilibanum and the West African S. squamosum. Length differences of the rDNA internal transcribed spacer 1 (ITS-1) turned out to be useful to distinguish between cytoforms.

The Simulium damnosum complex in western Uganda and its role as a vector of Onchocerca volvulus

The status of onchocerciasis vectors in the former Ruwenzori focus in western Uganda was re-examined some 15 years after control measures against Simulium damnosum s.l. were suspended. The four cytoforms S. kilibanum, 'Sebwe', 'Nkusi' and S. pandanophilum were found. While the nonanthropophilic 'Sebwe' was still widely distributed in rivers north, east and south of the Ruwenzori, the only anthropophilic species and vector, S. kilibanum, had disappeared from most of its former habitats and was now restricted to two limited foci, where high biting densities were encountered. It was still a vector south of the Ruwenzori (Kasese focus), where 15.4% of the parous flies were infected with larval stages of Onchocerca volvulus and 34 infective larvae were found in the heads of 1000 parous flies. In the second focus along the Mahoma and Nsonge rivers, a chromosomally highly polymorphic population of S. kilibanum had replaced the former vector S. neavei, but does not act as a vector. Only 2.3% of the parous females were infected and just 1 infective larva was found in the heads of 1000 parous flies.

An extractive membrane biofilm reactor for degradation of 1,3-dichloropropene in industrial waste water

A bacterial biofilm, capable of mineralising a technical mixture of cis- and trans-1,3-dichloropropene (DCPE), was enriched on the biomedium side of an extractive membrane biofilm reactor (EMBR). The membrane separates the biomedium from the industrial waste water, in terms of pH, ionic strength and the concentration of toxic chemicals. The biofilm, attached to a silicone membrane, is able to mineralize DCPE after its diffusion through the membrane. Five bacterial strains with degradation capabilities were isolated from the metabolically active biofilm and further investigated in batch experiments. Two of them, Rhodococcus erythropolis strains EK2 and EK5, can grow with DCPE as the sole carbon source. Pseudomonas sp. EK1 uzilizes cis-3-chloroallylalcohol and cis-3-chloroacrylic acid, whereas the metabolite trans-3-chloroacrylic acid represents a dead-end product of the pathway of this strain. The other two strains, Delftia sp. EK3 and EK4, although unable to grow with DCPE as the carbon source, can transform DCPE and its upper-pathway intermediates at reasonable conversion rates. They may represent helper functions of the biofilm consortium, which mineralised up to 12.5 mmol DCPE per hour per gram of biomass protein. Higher feed rates in the EMBR (up to 15 mmol per hour per 100-l bioreactor volume) and shock loads corresponding to concentrations up to 1.8 mmol l-1 led to a significant increase in the freely floating bacterial biomass in the reactor medium (OD546 = 0.2). At the standard operating feed rate of 1.8 mmol h-1, the free biomass concentration was very low (OD546 = 0.04).

Morphometric characterization of members of the Simulium damnosum Theobald complex (Diptera: Simuliidae) from East and West Africa

Morphometric multivariate analyses were carried out in order to separate the females of the closely related anthropophilic and non-anthropophilic members of the Simulium damnosum s.l. complex occurring in western Uganda. Simulium kilibanum (= 'Nyamagasani'), 'Nkusi', 'Sebwe' and S. pandanophilum were compared with the West African S. damnosum subcomplex, S. soubrense and S. yahense to correlate the results with those of previous studies. Simulium pandanophilum could be clearly discriminated. However, only 72%-88% of identifications among the closely related S. kilibanum, 'Sebwe' and 'Nkusi', which all belong to the 'Sanje' subcomplex, were correct. The two forest species S. soubrense and S. yahense slightly overlapped but were distinct from all others.

Marine radioactivity assessment of Mururoa and Fangataufa atolls

The International Atomic Energy Agency (IAEA) carried out an international project. 'The Study of the Radiological Situation at the Atolls of Mururoa and Fangataufa' with the aim of assessing the present and future radiological situation at the atolls and making recommendations for either monitoring or remedial actions if they are deemed necessary. The paper concentrates on marine radioactivity aspects and gives an estimation of present radionuclide concentrations in water, sediment and biota of the Mururoa and Fangataufa lagoons and the surrounding ocean. The dominant radionuclide in both lagoons is Pu in sediments (the total inventory is approximately 30 TBq). A decline in radionuclide concentrations has been observed in recent years in lagoon water, with the exception of 3H and 90Sr, for which a contribution from underground sources is to be expected. Radionuclide concentrations in biota from the lagoons and the surrounding ocean are low and consistent with previous measurements. The observed radionuclide concentrations in both lagoons imply that no radiological risk exists for hypothetical inhabitants of Mururoa and Fangataufa Atolls.

Combined treatment with serine protease inhibitor aprotinin and matrix metalloproteinase inhibitor Batimastat (BB-94) does not prevent invasion of human esophageal and ovarian carcinoma cells in vivo

Many studies have highlighted the role played by matrix metalloproteinases MMP-2 and -9, by serine proteases uPA and plasmin in tumor cell invasion. This study investigates the impact of the MMP-inhibitor Batimastat and/or the serine protease inhibitor Aprotinin on the in vitro proteolytic activity and in vivo invasive behavior the of esophageal (OC1) and ovarian (OVCAR-3) carcinoma cells. In presence and absence of inhibitors, proteolytic activity of the tumor cells was determined by caseinolytic and collagenolytic in vitro assays and tumor cell invasion by intraperitoneal inoculation of the tumor cells into nude mice. In vitro, Aprotinin, tested alone or in combination with Batimastat, efficiently inhibited degradation of collagen IV and casein by the tumor cells. Batimastat alone had no effect on caseinolytic activities and only partially blocked collagen-type-IV-degradation by the tumor cells. In vivo, Aprotinin tested alone or in combination with Batimastat did not prevent tumor cell invasion. Treatment of tumor bearing mice with Batimastat significantly inhibited tumor growth but promoted tumor cell invasion into the liver. Our findings demonstrate that the inhibition pattern of cellular proteolytic activity achieved in vitro by a serine protease and an MMP inhibitor may lead to predictions that are not necessarily verified in vivo and may even have adverse effects.

Involvement of CD28 cosignalling in the T cell-mediated suppression of the IgG antibody response against the TI-2 antigen alpha(1-->3) dextran

The humoral immune response against alpha(1-->3) dextran (Dex) in BALB/c mice is characterized by the formation of predominantly IgM antibodies bearing the J558 idiotype. IgG antibodies do not appear in euthymic mice. In athymic animals, however, the response proceeds to a vigorous IgG production. In euthymic mice formation of IgG is suppressed by J558 idiotype specific regulatory T cells recognizing in association with I-Ed and in cognate T/B interaction the V(H) CDR3 derived peptide of the J558 idiotype. Only B-2 lymphocytes produce IgG whereas B-1 cells do not participate in the production of this Ig class. Using novel synthetic all alpha(1-->3)-D-gluco configured tetrasaccharide the Dex-specific B cells can for the first time be analyzed in FACS. In experiments using this newly designed low molecular Dex no signs of B cell apoptosis can be found. This demonstrates a true silencing of persisting Bgamma memory cells as previously suggested by adoptive transfer experiments. In this suppression a further involvement of CD28 and B7-1 interaction can be demonstrated which delivers a necessary costimulatory suppression signal in addition to the cognate TCR/peptide-I-Ed interaction between J558 specific T cells and J558 idiotype bearing B cells.

The bacterial lacZ gene: an important tool for metastasis research and evaluation of new cancer therapies

The bacterial lacZ gene has been used to genetically tag tumor cells. This has been of value, specifically in metastasis research where it allowed to visualize micrometastases and single tumor cells in tissues. lacZ tagging has also provided the feasibility of re-isolating metastatic tumor cell populations for ex vivo molecular analyses. This review summarizes studies that have utilized lacZ tagged tumor cells to understand aspects of metastasis including dormancy, tumor-host interactions, gene modulation and anti-tumor immunity. lacZ tagging is also a valuable tool for evaluating cancer therapies.

Anterior debridement, fusion, and extrafocal stabilization in the treatment of osteomyelitis of the spine

To simplify and shorten the rehabilitation after anterior debridement and fusion in pyogenic and tuberculous osteomyelitis of the spine, the role of additional extrafocal dorsal transpedicular instrumentation was studied. Thirty-three (10 female, 23 male) patients were followed up in a prospective study and controlled with an average follow-up period of 22.1 months after the operation with clinical and neurologic check-up, blood test, and serial radiographs. Solid bony fusion and healing of the infection was achieved in all patients. Preoperative deformities could be corrected, and there were no life-threatening complications. Dorsal extrafocal stabilization offered the advantage of braceless rehabilitation without adding unpredictable risks.

[Factitious skin lesions as an expression of a family crisis]

The factitious disorder is a deliberately induced, hidden self-mutilation based on a psychic conflict. We present a previously healthy nine-year old girl with initially obscure symmetric skin lesions. Family history, psychological exploration, special tests like pictural expression and scenial exhibition revealed the child's fear of a divorce of her parents and her own identity problem. These examinations aroused the suspicion that the girl could only express her conflict of ambivalence by self-injury behavior in the meaning of artificial disease. Guided by this impression, an intensive conversation with both parents was undertaken, focussing the familiar crisis. Afterwards, the skin lesions disappeared the girl admitted the self-mutilation. A family therapy was initiated.

A new species of the Simulium damnosum complex from Uganda, and comparative morphology of the tarsal claws in females of this complex

The female, male, pupa and larva of Simulium (Edwardsellum) pandanophilum sp. nov. (Diptera: Simuliidae) from western Uganda are described. Diagnostic features are the shape of the tarsal claws of females and, cytogenetically, new intraspecific inversions on chromosomes I and II. Simulium pandanophilum is assigned to the Simulium damnosum complex. Different tarsal claw shapes of West African members of the S. damnosum complex are also described.

Host TIMP-1 overexpression confers resistance to experimental brain metastasis of a fibrosarcoma cell line

Within the tumor-stromal microenvironment a disrupted balance between matrix metalloproteinases (MMPs) and their inhibitors compromises the integrity of the extracellular matrix and promotes malignancy. Tissue inhibitors of metalloproteinases (TIMPs) have been linked to tumor suppression in studies of genetically altered tissue culture cells and in analyses of clinical specimens in situ. We generated transgenic mice as a model system to test the relationship between TIMP-1 levels in a host organ and susceptibility to experimentally targeted metastasis. Ectopically overexpressed TIMP-1 in the brain resulted in a tissue microenvironment with elevated protein levels of this natural MMP inhibitor. Metastatic challenge provided by lacZ-tagged fibrosarcoma cells permitted high-resolution analysis of metastatic load and pattern. We found that elevated host TIMP-1 imposed resistance to experimental metastasis of fibrosarcoma: In TIMP-1 overexpressing mice, brain metastases were significantly reduced by 75% compared to wild-type littermates. Our findings demonstrate that ectopic TIMP-1 expression efficiently exerts a suppressive effect on metastasizing tumor cells.

[Differential diagnosis of erosive osteochondrosis and bacterial spondylitis: magnetic resonance tomography (MRT)]

PURPOSE

To evaluate retrospectively criteria in the differential diagnosis of erosive osteochondrosis (EO) and infectious spondylitis (IS) on the basis of MRI.

METHODS

T1-weighted sagittal images before and after Gd-DTPA application, T2-weighted TSE or T-STIR images of 23 patients with proven 15 and 41 patients with EO were evaluated. Criteria for this evaluation were morphology and extension of bone marrow edema, visibility of the low-intensity vertebral endplate, contrast enhancement and signal intensity in the disc space on T2-weighted and T-STIR images.

RESULTS

Bone marrow edema was more extensive in IS than in EO. The mean rated value for bone marrow edema on a four-level scale (0-3) was for IS 2.91 (+/- 0.29), for EO 1.32 (+/- 0.76, p < 0.001). In 37/41 cases of EO and in 22/23 cases of IS Gd-DTPA enhancement was found in the disc space (n.s.). In EO the low intensity endplate was visible in all parts in 36/41 cases (87.8%) on T1-weighted images, in IS not in a single case (0%). On T2-weighted or STIR images signal intensity of the discs was decreased in 82.1% of EO, 82.6% of segments in IS had water-equivalent signal intensity (p < 0.001).

CONCLUSION

If all the criteria are taken into consideration differential diagnosis of EO and IS on the basis of MRI findings is possible.

[Comparative periprosthetic bone density measurements of the proximal femur shaft using dual energy x-ray absorptiometry (DEXA) with experimental "Press Fit-gliding Stem Prosthesis"]

PROBLEM

Periprosthetic bone atrophy caused by stress shielding is one of the problems of non-cemented femoral stems of hip arthroplasty. Stress shielding and thus the loss of bone mass and their dissemination in the proximal part of the femur of conventional non-cemented femoral stems depends on stiffness (E-modules of the material and the geometry) of the implant and on the bonding between implant and bone. All currently implanted non-cemented femoral stems lead to proximal bone loss which goes up to 40-50% of the original bone mineral content. The senior author (E. M.) developed a femoral stem (Press Fit-Gliding Stem PFGS) which shifts relative movements of force-transmission from the bone-implant interface into the interior of the prosthetic system (Inner Bearing-System) and which only transfers forces proximal into the femur.

METHOD

The examinations were made in 21 patients between 1 and 6 years after implantation of a Press Fit-Gliding Stem compared with a normal contralateral femur (12), with bilateral PFGS (3) and other bilateral arthroplasty (6).

RESULTS

In all 21 patients supplied with a PFGS an increase of bone mineral content (BMC) and bone mineral density (BMC) in zone 7 as well as a marked smaller deviation around the mean value in all zones respectively could be noticed.

CONCLUSIONS

With the Dual Energy X-ray Absorptiometry (DEXA)-measurement of bone mineral content (BMC) and bone mineral density (BMD) in all zones according to Gruen could be shown that it is not only possible with regard to a favorable force transmission to avoid the inevitable bone atrophy but on the contrary to induce an increase of bone at the point of local force transmission that is in the region of the calcar femorale (zone 7).

CLINICAL RELEVANCE

The Press Fit-Gliding Stem is still in the clinical test-program.

Altered tumor growth and metastasis of a T-cell lymphoma in Timp-1 transgenic mice

The concept of tumor suppression by tissue inhibitor of metalloproteinases (TIMPs) has evolved primarily from studies of genetically modulated tumor cells. The next step is to focus on the host and assess the protective potential of host TIMP-1 on primary tumor growth and metastasis. We generated two transgenic mouse lines with altered Timp-1 expression in skin and liver: one overexpressed Timp-1 (Timp-1(high)), and the other had antisense RNA-mediated Timp-1 reduction (Timp-1(low)). ESbL-lacZ T-lymphoma cells provided the tumor challenge, as they form primary tumors upon intradermal injection with spontaneous metastasis to liver. Metastases were examined in X-Gal-stained whole-organ mounts. Timp-1 overexpression inhibited intradermal tumor growth and spontaneous metastasis, leading to prolonged survival of the mice. The opposite effects occurred in Timp-1(low) mice, leading to shorter host survival. Experimental metastasis assays showed that Timp-1-compromised livers in Timp-1(low) mice showed at least a doubling of metastatic foci and numerous additional micrometastases, indicative of increased host susceptibility. However, Timp-1(high) mouse livers showed an unaltered metastatic load in the experimental metastasis assay. In conclusion, these data demonstrate that Timp-1 levels within a tissue predetermine the development and progression of T-cell lymphoma.

Discrete synchronous multifocal osteoid osteoma of the humerus

A 24-year-old patient is described who had a 4-year history of pain in the right upper arm, with distinct night pain, that responded to salicylates. From the findings on conventional radiography, bone scintigraphy and MRI a multifocal osteoid osteoma was suspected, with one focus in the cancellous region of the greater tuberosity and a second cortical focus at the proximal humeral diaphysis. The resection "en bloc" of both tumors and histological examination confirmed the diagnosis. The patient was painfree after the curative resection of the two osteoid osteomas. Osteoid osteoma is a frequently found benign bone tumor, accounting for approximately 11% of cases. In rare cases a multicentric occurrence has been described. A possible occurrence of more than one osteoid osteoma in a single bone, not verified histologically, has been reported only three times in the literature. In patients with scintigraphic and radiographic findings of two foci, discrete synchronous multifocal osteoid osteomas should be suspected.