PubMed Health⌕ Search

Biomedical subjects

R Gassner

Publications and source records attributed to R Gassner.

28 records · Page 2Linked to original sources
PubMed1999

Cyclic tensile stress exerts antiinflammatory actions on chondrocytes by inhibiting inducible nitric oxide synthase.

Continuous passive motion manifests therapeutic effects on inflamed articular joints by an as-yet-unknown mechanism. Here, we show that application of cyclic tensile stress (CTS) in vitro abrogates the catabolic effects of IL-1beta on chondrocytes. The effects of CTS are mediated by down-regulation of IL-1beta-dependent inducible NO production, and are directly attributed to the inhibition of inducible NO synthase (iNOS) mRNA expression and protein synthesis. The inhibition of iNOS induction by CTS is paralleled by abrogation of IL-1beta-induced down-regulation of proteoglycan synthesis. Furthermore, CTS inhibits iNOS expression and up-regulates proteoglycan synthesis at concentrations of IL-1beta frequently observed in inflamed arthritic joints, suggesting that the actions of CTS may be clinically relevant in suppressing the sustained effects of pathological levels of IL-1beta in vivo. These results are the first to demonstrate that mechanisms of the intracellular actions of CTS in IL-1beta-activated chondrocytes are mediated through inhibition of a key molecule in the signal transduction pathway that leads to iNOS expression.

Animals↗
PubMed1999

Multivitamin administration before ischemia reduces ischemia-reperfusion injury in rabbit skeletal muscle.

This study investigated the effect of a multivitamin preparation administered before ischemia or before reperfusion, on ischemia-reperfusion (I/R) injury of skeletal muscle. An in vivo hindlimb skeletal muscle I/R model (2.5 h/2 h) was carried out on adult New Zealand white rabbits. Animals used as I/R models were treated with a multivitamin preparation (0.4 ml/kg bw i.v. bolus), containing alpha-tocopherol, ascorbic acid, retinol, vitamin B complex, 30 min before starting ischemia (group MV(isc)) or 5 min before reperfusion (group MV(rep)) and compared to animals with I/R without treatment (group IR) and sham operated animals (group SHAM). Interstitial edema (muscle interfiber area, %MIFA) and changes in microvessel size (microvessel cross sectional area, MVCSA, microm(2)) were measured. Plasma malondialdehyde concentrations (MDA-TBA, nmol/ml) served as a measure of lipid peroxidation. After 2h of reperfusion, ischemia-reperfusion developed a significant microvascular constriction and an interstitial edema (IR, vs SHAM;P<< 0.01), but administration of antioxidative vitamins before the onset of ischemia reduced microvascular constriction and edema formation (P<< 0.05 vs IR group). In a similar manner, administration of vitamins before ischemia lowered plasma MDA-TBA levels as compared to the untreated group during reperfusion (p<< 0. 05). In animals treated with vitamins before reperfusion, the biochemical and morphological results showed no differences as compared to the untreated group. Antioxidative treatment with a multivitamin preparation exerted a beneficial effect on I/R injury of skeletal muscle when the aforementioned vitamins were administered before ischemia but not before the onset of reperfusion.

Animals↗
PubMed1999

Incidence of oral and maxillofacial skiing injuries due to different injury mechanisms.

PURPOSE: This study emphasizes the significance of maxillofacial injuries in skiing accidents, correlating injury mechanisms and patterns, by evaluating a large population of maxillofacial injuries over a 6-year period. PATIENTS AND METHODS: Between 1991 and 1996, of 5,623 patients showing oral and maxillofacial injuries, 1,859 were sports-related. Records of 579 patients with 882 incidents of oral and maxillofacial injury due to skiing were reviewed and analyzed according to age, sex, type of injury, cause of accident, location, and frequency of fractures. Additionally, the five main injury mechanisms were analyzed. RESULTS: The oral and maxillofacial injuries in 10.3% of all trauma patients, or 33% of all sports-related trauma patients, were due to skiing. A total of 310 patients (53.5%) had facial bone fractures, 236 patients (40.8%) suffered from dentoalveolar trauma, and 336 patients (58%) showed soft tissue injuries. Five major causes and mechanisms of injury existed, namely, 263 falls (45%); 135 collisions with other skiers (23%); 70 individuals struck by their own ski equipment (12%); 46 collisions against stationary objects (8%); and 34 lift-track accidents (6%). Sex distribution showed an overall male-to-female ratio of 1.9:1.0, but varied depending on the injury mechanism. The age distribution ranged from 2 to 81 years. CONCLUSION: The results of this study show the high incidence of oral and maxillofacial injuries due to skiing accidents. Depending on the mechanism of injury, different patterns occur. Facial bone fractures are more likely in collisions with other persons, falls, and collisions with stationary objects, whereas dentoalveolar trauma is more common when persons are struck by their own ski equipment, or when accidents on lift-tracks occur.

Accidental Falls↗
PubMed1999

Prevalence of dental trauma in 6000 patients with facial injuries: implications for prevention.

OBJECTIVE: In contrast to epidemiologic studies on facial injuries reporting on dental trauma, facial bone fractures with dentoalveolar injuries, or soft tissue injuries individually, the purpose of this study was to evaluate the overall place of dental trauma in facial injuries. This was a retrospective investigation of the impact of sport, work, violence, traffic, household, and play accidents in the relationships among dental trauma, facial trauma, and other concomitant trauma. Finally, preventive considerations are discussed. STUDY DESIGN: Six thousand patients registered at the University Hospital of Innsbruck's Department of Oral and Maxillofacial Surgery during a period of 6 years 4 months were admitted for dental trauma, facial trauma, or both. Records were analyzed for cause of injury, age, gender, monthly distribution, frequency, type of injury, and frequency of dental trauma in relation to facial injuries and concomitant injuries. RESULTS: The incidence of dental injuries with respect to the total number of facial injuries was as follows: 57.8% in play and household accidents, 50.1% in sports accidents, 38.6% in accidents at work, 35.8% in acts of violence, 34.2% in traffic accidents, and 31% in unspecified accidents. The overall incidence revealed was 48.25%. CONCLUSION: Our findings support the fact that in the mosaic of traumatic injuries, the frequencies of tooth trauma and its sequelae are underestimated and that such trauma and sequelae occur without a predictable pattern of intensity and extensiveness. Preventive approaches are the sole way to minimize the number of these injuries. Substantial progress made in treating facial and dental trauma in the last 2 decades only improves functional and esthetic outcomes among the population that has suffered dental injury.

Accident Prevention↗
PubMed1999

Facial injuries in skiing. A retrospective study of 549 cases.

In the last 2 decades, reports of skiing injuries have shown an increasing number of skiers with severe trauma. This article provides an account of a retrospective study of 549 patients with 1155 facial injuries sustained while skiing who received treatment at the Department of Oral and Maxillofacial Surgery at the University Hospital in Innsbruck, Austria between 1991 and 1996. The study was based on a questionnaire answered by the patients and on case report forms. Most of the patients were male (65.2%) and were aged between 3 and 81 years (average 28.4 years). A simple fall while skiing was the main type of accident (45.9%), followed by collisions with other people (23.5%). Injuries were classified into 1 of 3 groups: (i) lesions of the soft tissue (32.2% of all injuries); (ii) dentoalveolar traumas (24.3%); and (iii) fractures of facial bones (43.5%). Lacerations and haematomas were the most frequent lesions in patients with injuries to the soft tissues. The group of patients with dentoalveolar trauma mainly presented with fractures of tooth crowns. Fractures involving the mandible and the zygomatic bone were predominant in patients in the third group. Concomitant injuries mainly included injuries to the brain and skull fractures. Treatment was ambulatory, or by admission and surgery. We did not observe an increase in the number of skiing accidents causing facial injury in the last 5 years. Facial injuries represented 4% of all skiing injuries, a lower proportion than in other sports.

Accidental Falls↗
PubMed1999

Mountainbiking--a dangerous sport: comparison with bicycling on oral and maxillofacial trauma.

The popularity of bicycling is reflected in the number of cycling-related oral and maxillofacial injuries. Five hundred and sixty-two injured bicyclists (10.3% of all trauma patients) were registered at the Department of Oral and Maxillofacial Surgery, University of Innsbruck, Austria, between 1991 and 1996, accounting for 31% of all sports-related accidents and 48.4% of all traffic accidents. A review of the patient records revealed more severe injury profiles in sixty mountainbikers, with 55% facial bone fractures, 22% dentoalveolar trauma and 23% soft tissue injuries, compared to 502 street cyclists showing 50.8% dentoalveolar trauma, 34.5% facial bone fractures and 14% soft tissue lesions. The dominant fracture site in bicyclists was the zygoma (30.8%), whereas mountainbikers sustained an impressive 15.2% LeFort I, II and III fractures. Condyle fractures were more common in bicyclists, with 18.8% compared to 10.8% in mountainbikers. Reduction of facial injuries due to cycling-related accidents needs appropriate design of helmets with faceguards and compulsory helmet use for all cyclists, and particularly mountainbikers.

Accidental Falls↗
PubMed1999

Tissue engineering and dentistry.

This article assesses the current state of the art of tissue engineering and its applications in dentistry, especially in the reconstruction and repair of orofacial tissues, including bone and oral mucosa, for the restoration of function and improved cosmetics. The article discusses at length the tissue engineering of bone and cartilage, including guided tissue techniques, in which some of the most interesting advances in the field are being made.

Biocompatible Materials↗
PubMed1997

The diagnostic value of ultrasonography to determine the temporomandibular joint disk position.

OBJECTIVE: Temporomandibular joint (TMJ) arthrography and magnetic resonance imaging are the imaging techniques of choice in patients presenting with signs and symptoms of TMJ disorders suggesting soft tissue pathosis. With the disadvantage of arthrography as an invasive procedure and magnetic resonance imaging posing a problem in clinical availability and cost, the purpose of this study was to determine whether ultrasonography could be used to assess the presence or absence of disk displacement in patients with TMJ disorders. STUDY DESIGN: In 17 patients, 100 TMJ positions were investigated by static and dynamic ultrasonography to analyze the disk-condyle relationship. To compare the respective findings with those of a diagnostic method offering high accuracy, coronal and sagittal magnetic resonance imaging was carried out immediately afterwards. RESULTS: With static ultrasonography showing a sensitivity of 0.41 and a specificity of 0.70 and dynamic ultrasonography a sensitivity of 0.31 and a specificity of 0.95, the data revealed that static and dynamic ultrasonography are marginal in detecting the presence of disk displacement, but dynamic ultrasonography is sensitive in detecting the absence of disk displacement. However, with a positive predictive value of 0.61 and a negative predictive value of 0.51 for static ultrasonography, and a positive predictive value of 0.88 and a negative predictive value of 0.55 for the dynamic technique, the results indicate that both modalities are insufficient in establishing a correct diagnosis for the presence or absence of disk displacement. CONCLUSION: In view of the fact that dynamic ultrasonography proved to be a reliable diagnostic aid for the detection of normal disk position, the results of this study should be of further interest and encourage research in its potential uses and diagnostic capabilities.

Adolescent↗
PubMed1991

Pancreatic transplantation with delayed duct occlusion versus bladder drainage: long-term results.

Between April 1985 and August 1990 a total of 51 combined pancreas kidney transplants and 6 single pancreas transplants were performed in 51 Type 1 (insulin - dependent) diabetic patients suffering from end-stage diabetic nephropathy and three patients with proliferative retinopathy. In 17 transplants the pancreatic duct was occluded with a mean delay of 53 days (Group 1). Because of a high incidence of local complications associated with a prolonged hospitalization this technique was abandoned despite favourable results: The actual survival rates for patients, pancreas and renal allografts at 1 year are 94%, 72% and 93%, respectively. From 1987 a total of 39 consecutive segmental pancreas grafts were anastomosed with the urinary bladder (Group 2). Pancreatic secretions were temporarily drained to the exterior in all patients via a duct catheter. Monitoring of the exocrine function including pancreatic secretion cytology and pancreatic secretion neopterin excretion proved to be reliable rejection markers. Survival rates at 1 year were calculated to be 90%, 74% and 89% for all patients, pancreas grafts and renal grafts. Apart from local complications in group I which did not cause any graft loss, the surgical complication rate was comparably low in both groups.

Adult↗