Biomedical subjects

Dubravko Orlić

Publications and source records attributed to Dubravko Orlić.

9 recordsLinked to original sources

PubMed2006

Single nucleotide polymorphisms in the interleukin-6 gene promoter, tumor necrosis factor-alpha gene promoter, and transforming growth factor-beta1 gene signal sequence as predictors of time to onset of aseptic loosening after total hip arthroplasty: preliminary study.

BACKGROUND: Aseptic loosening resulting from inflammatory response to the implant wear debris is the major cause of late total hip arthroplasty (THA) failure. We examined single nucleotide polymorphisms in genes encoding for three involved cytokines--interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-alpha), and transforming growth factor-beta1 (TGF-beta1)--as potential predictors of time to onset of aseptic instability. METHODS: A total of 41 patients/45 total hip endoprostheses (same type, same surgeon) were followed up for as long as 18 years. They were genotyped for the IL-6 promoter (-597G-->A) and (-572G-->C), TNF-alpha promoter (-308G-->A), and TGF-beta1 signal sequence (29T-->C) transitions. Cox regression was performed on the prosthesis survival. RESULTS: Overall, 22 of 45 prostheses developed aseptic instability. Cumulative survivals at 10 and 15 years after THA were 95.6% and 66.6%, respectively. The effect of a particular polymorphic site was estimated with adjustment for sex, age at THA, reason for THA, and the effects of other analyzed sites. The hazard ratio (HR) for genotype T/T versus "C-allele carriage" at the TGF-beta1 site was 8.23 [95% confidence interval (CI) 1.45-46.8] (P=0.017) or 5.70 (1.39-23.4) (P=0.016) when the IL-6 promoter sites were considered as a "combination of genotypes (-597)|(-572)." The most prevalent combination of genotypes at IL-6 sites was G/A (-597)|C/C (-572). HR for this combination (versus other combinations) was 5.43 (1.73-17.0) (P=0.004) when "TGF-beta1 (29T-->C)" was considered as a three-level factor (three possible genotypes), and 4.92 (1.71-14.1) (P=0.003) when TGF-beta1 site was considered as a two-level factor (T/T and "C-allele carriage"). The HR for the "A-allele carriage" at TNF-alpha (-308G-->A) could not be determined (only two patients had the G/G genotype). CONCLUSIONS: This preliminary study is the first to suggest that the TGF-beta1 signal sequence (29T-->C) and IL-6 promoter (-597G-->A)|(-572G-->C) transitions are predictive for the time to onset of aseptic instability after THA.

Adult↗

PubMed2006

Angiogenesis and Ewing sarcoma--relationship to pulmonary metastasis and survival.

BACKGROUND/PURPOSE: Intratumoral angiogenesis quantified by microvessel density (MVD) has been shown to be a strong prognostic indicator in a number of malignant tumors. Its association with prognosis in Ewing sarcoma has not been previously studied. The aim of our study was to investigate the relationship between angiogenesis and clinical outcome in Ewing sarcoma. METHODS: Twenty-seven patients with Ewing sarcoma were included in a retrospective immunohistochemical study. Sections from diagnostic biopsies were immunostained using anti-von Willebrand factor antibody and microvessels were counted at 400x magnification on three microscopic fields per patient. Microvessel density was correlated with overall and disease-free survival as a continuous variable using univariate regression analysis and as a dichotomous variable by Kaplan-Meier and log-rank analysis. Correlation between clinicopathologic variables and the degree of angiogenesis was tested using chi(2) test. RESULTS: Increasing MVD was not confirmed to be a poor prognostic factor in univariate analysis. Also, statistically significant difference was not found in overall survival or disease-free survival between patients with high (>31.6 vessels per field) and low (<or=31.6 vessels per field) microvessel counts. Finally, there was no difference regarding the metastatic rate between patients with high and low microvessel counts. CONCLUSIONS: Our results did not confirm increasing angiogenesis quantified by MVD to be predictive of prognosis or pulmonary metastasis in Ewing sarcoma. The diffuse pattern of distribution of microvessels found in Ewing sarcoma may be responsible for the observed lack of prognostic significance of angiogenesis. Future work is required to assess the prognostic importance of MVD in this disease.

Adolescent↗

PubMed2005

Stability of Endler cementless polyethylene acetabular cup: long-term follow-up.

AIM: To investigate the possible influence of demographic and biomechanical factors on stability of the Endler cementless polyethylene acetabular cup. METHODS: This was a retrospective cohort study. Seventy-two patients (25 men, 47 women) bearing 82 Endler prostheses, all of which were implanted by the same surgeon in the period between 1985 and 1991, were invited for a control visit (final visit) in July 2003. During time between the surgery and the final visit, the patients were followed-up regularly and assessed for clinical and radiological signs of the Endler cup instability based on Krugluger and Eyb's criteria. The Kaplan-Meier product limit method and the Cox proportional hazard regression analysis were used to investigate the survival of the cup (time since implantation till the diagnosis of instability) and possible influence of the following factors: age and body mass index at the time of surgery, gender, achieved acetabular cup inclination angle, and acetabuloplasty and/or trochanter osteotomy performed during surgery. RESULTS: The median follow-up period was 15 years (range 5-18). Cumulative survival rates at 5, 10, 15, and 18 years were 97.6% (95% CI=94.2-100), 74.4% (95% CI=64.9-83.8), 53.7% (95% CI=42.9-64.5), and 44.5% (95% CI=29.5-59.6), respectively. The median survival time was 18 years (13-18). Unsatisfactory acetabular cup inclination angle (<41 or >49 degrees) was a negative predictor of the cup survival (P=0.026), whereas the interaction between the inclination angle and an unsatisfactory body mass index (>upper normal limit) was of borderline significance (P=0.056). The analyzed demographic and biomechanical factors apparently explained only a minor part of the survival variability (R(2)=0.173). CONCLUSION: This study further documents the impact of the acetabular cup inclination angle achieved at surgery on the Endler cup survival. However, it also suggests that the prosthesis survival might be influenced by other, non-biomechanical factors.

Acetabulum↗

PubMed2004

Osteosarcoma and Ewing's sarcoma in children and adolescents: retrospective clinicopathological study.

AIM: Almost 20 different prognostic factors have so far been investigated in childhood bone tumors, but apart from clinical stage the results have been inconclusive. We evaluated possible prognostic factors of malignant bone tumors in children and adolescents. METHODS: Seventy children and adolescents, who have been treated for bone sarcomas (36 with osteosarcoma and 34 with Ewing's sarcoma) at the Children's Hospital in Zagreb and the Orthopedic Clinic of the Zagreb University School of Medicine were included in the study. We analyzed 9 variables: clinical stage, patient age and sex, tumor size and location, location of metastases, chemotherapy response, concentration of lactate dehydrogenase (LDH) and erythrocyte sedimentation rate (ESR), and chondroid differentiation in osteosarcoma. RESULTS: The clinical stage was the most important prognostic factor for both type of tumors. Lactate dehydrogenase in patients with Ewing's sarcoma (p=0.033) and in patients with osteosarcoma (p=0.015) as well as erythrocyte sedimentation rate (p<0.001 and p=0.014, respectively) may also be of predictive value. CONCLUSION: Elevated erythrocyte sedimentation rate and high LDH concentration seem to be of importance in both Ewing's sarcoma and osteosarcoma, regardless of their different pathogenesis or pathohistology.

Adolescent↗

PubMed2003

[Endoprosthetic procedures in rheumatoid patients].

Rheumatoid diseases are generalized chronic inflammatory diseases of the musculoskeletal system. Although the different structures and different joints are affected, all cause a very uniform type of pathology and joint destruction. The main indication for implantation of the endoprosthesis are severe pain and walking disability with poor quality of life. On the X-ray involvement includes periarticular osteopenia, cystic changes, and destruction's affected joints. Endoprosthetic replacement has been successful in the treatment of severe rheumatoid disease of almost all joints of all ages, but predominantly replacement of the hip, knee, shoulder, elbow and MCP joints. Arthroplasty has proved to be an excellent addition to the therapeutic armamentarium for the rehabilitation of handicapped patients with rheumatoid disease. Advancements in endoprosthetic technology and surgical techniques, allow us to perform alloarthroplasty in most of the patients with severe rheumatoid disease of all different joints.

Arthritis, Rheumatoid↗

PubMedDate not supplied

Arthroscopic removal of a juxtaarticular osteoid osteoma of the talar neck.

The authors report a case of a 21-year-old woman with osteoid osteoma of the talar neck that was treated with arthroscopic resection. The nidus was removed in one piece with grasping forceps, and histopathologic findings confirmed the preoperative diagnosis of osteoid osteoma. Postoperatively, the patient was immediately relieved of ankle pain and there was no recurrence at the 1-year follow-up. If possible, the nidus should be removed without the use of a motorized instrument to ensure the correct histolologic diagnosis.

Adult↗

PubMedDate not supplied

Tumor angiogenesis and outcome in osteosarcoma.

Intratumoral angiogenesis quantified by microvessel density (MVD) has been shown to be a strong prognostic indicator in a number of malignant tumors. Its association with prognosis in bone sarcomas has been subject to less extensive research. The aim of this study was to investigate prognostic significance of angiogenesis in osteosarcoma. Thirty-nine patients with osteosarcoma were included in a retrospective immunohistochemical study. Sections from diagnostic biopsies were immunostained using anti-von Willebrand factor antibody and microvessels were counted at 400 x magnification on 3 microscopic fields per patient. MVD was correlated with overall and disease-free survival by Kaplan-Meier and log-rank analysis. Correlation between clinicopathological variables and the degree of angiogenesis was tested using a chi 2 test. Significant statistical difference was found regarding overall survival and disease-free survival between patients with high (> 32.3 vessels/field) and low (< or = 32.3 vessels/field) microvessel counts (log-rank test p = .0196 and p = .0147, respectively). The rate of metastasis was significantly higher in patients with high microvessel counts (p = .042). These findings strongly suggest that angiogenesis quantified by microvessel density is predictive of metastasis and poor prognosis in osteosarcoma.

Adolescent↗

PubMedDate not supplied

[Emergencies in total hip replacement].

Over the last three decades total hip replacement became one of the most common surgical procedures in orthopaedic surgery. According to the number of large joint endoprosthesis, hip replacement is on the first place. Lately, the number of revisional and special tumoral endoprosthesis is increasing, with more severe complications. Dislocation is a leading early complication of total hip arthroplasty. Dislocations after primary total hip arthroplasties occur at an overall incidence of 1-3%, and at 15-20% in revision and tumoral procedures. Closed reduction and eventually immobilization is the method of treatment. If closed reposition in not possible, revision surgery must be performed. Periprosthetic fractures are, as every other fracture, indication for a surgical treatment. Depending on the type of fracture the method of treatment is either open reduction and internal fixation or removal of the primary and implantation of revision endoprosthesis. Deep infection following total joint replacement remains one of the most serious complications, often needing surgical treatment. Treatment consists of incision and debridement. If there is a fever, increased erythrocyte sedimentation and CRP with signs of sepsis, endoprosthesis must be removed. A haematoma appearance after surgical procedure is an emergency which needs a surgical treatment--haematoma evacuation in order to prevent further complication, on the first place infection. Fractured endoprosthesis is one of the most severe complication in the total hip replacement, and need to be surgically treated as soon as possible with endoprosthesis replacement. Aseptic loosening can also be considered as a relative emergency in surgical treatment of total hip replacement. Longer waiting for reoperation can cause losing valuable bone mass needed for revisional endoprosthesis implantation and fixation. Although emergencies in hip replacement are not very common, they must be recognized and eventually surgically treated as soon as possible.

Arthroplasty, Replacement, Hip↗

PubMedDate not supplied

[Emergencies by tumors of locomotors systems in child and adults].

Tumours of locomotors system regardless whether they are primary or secondary, malign or benign, are regarded as urgent conditions in orthopaedics. The goal is early identification, urgent processing and diagnosing within as short period of time as possible in order to start the appropriate treatment. Since such tumours are most common in childhood and with teenagers, when anamnesis and clinical data cannot be specific and they are various, it is an imperative to identify and diagnose them early.

Adult↗