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1.
Orthopade ; 48(12): 1030-1035, 2019 Dec.
Article in German | MEDLINE | ID: mdl-31659423

ABSTRACT

Physical activity and exercise is widely connected with positive effects on human health. However, exercise may also pose as a risk factor for health under specific circumstances. Primarily, the risks connected with exercise are physical risks, but also psychological risks may appear, especially when exercise is conducted excessively. Psychological risks include eating disorders, illegal and legal substance use and exercise dependence. The aims of the present article are to focus on potential risks and side effects of exercise and physical activity and to put the risks in the context of the positive effects of exercise on health.


Subject(s)
Behavior, Addictive/psychology , Exercise/psychology , Feeding and Eating Disorders/psychology , Substance-Related Disorders/psychology , Behavior, Addictive/complications , Exercise/physiology , Feeding and Eating Disorders/complications , Humans , Risk Factors , Substance-Related Disorders/complications
2.
Knee Surg Sports Traumatol Arthrosc ; 22(8): 1926-31, 2014 Aug.
Article in English | MEDLINE | ID: mdl-24832693

ABSTRACT

PURPOSE: The objective of the study was to clarify whether driving abstinence should be recommended when patients are discharged from hospital after unicompartmental knee arthroplasty (UKA). We tested the hypotheses that there are differences in the peri-operative course of brake response time in patients undergoing right-sided (1) or left-sided (2) UKA. Additionally, we tested whether brake response time is significantly influenced by pain (3), driving experience (4) or age (5). METHODS: In 43 patients undergoing UKA, brake response time was measured with a custom-made driving simulator pre-operatively and 1 and 6 weeks after UKA. Patients' visual analogue scales for knee pain and their self-reported driving experience were also assessed. RESULTS: In patients with right-sided UKA, brake response time changed from 786 (261) ms pre-operatively to 900 (430) ms 1 week post-operatively (p = 0.029). At 6 weeks post-operatively, brake response time had returned to 712 (139) ms, which was deemed to be an insignificant change from the pre-operative reference benchmark. When surgery was performed on the contralateral left side, no effect was found onto the right side's brake response time. Knee pain and driving experience were significantly correlated with brake response time. No such correlations were found between brake response time and age. CONCLUSIONS: On the basis of the current findings, it is concluded that brake response time returns to pre-operative levels 6 weeks after UKA surgery. Therefore, it is proposed that driving be abstained from for that period.


Subject(s)
Arthroplasty, Replacement, Knee , Automobile Driving , Osteoarthritis, Knee/physiopathology , Osteoarthritis, Knee/surgery , Reaction Time , Aged , Arthralgia/diagnosis , Arthralgia/physiopathology , Female , Humans , Knee Joint/physiopathology , Knee Joint/surgery , Male , Middle Aged , Patient Education as Topic , Postoperative Period , Recovery of Function
3.
Arch Orthop Trauma Surg ; 132(9): 1299-313, 2012 Sep.
Article in English | MEDLINE | ID: mdl-22669543

ABSTRACT

With the rising number of anterior cruciate ligament (ACL) reconstructions performed, revision ACL reconstruction is increasingly common nowadays. A broad variety of primary and revision ACL reconstruction techniques have been described in the literature. Recurrent instability after primary ACL surgery is often due to non-anatomical ACL graft reconstruction and altered biomechanics. Anatomical reconstruction must be the primary goal of this challenging revision procedure. Recently, revision ACL reconstruction has been described using double bundle hamstring graft. Successful revision ACL reconstruction requires an exact understanding of the causes of failure and technical or diagnostic errors. The purpose of this article is to review the causes of failure, preoperative evaluation, graft selection and types of fixation, tunnel placement, various types of surgical techniques and clinical outcome of revision ACL reconstruction.


Subject(s)
Anterior Cruciate Ligament Reconstruction/methods , Anterior Cruciate Ligament/surgery , Knee Injuries/surgery , Anterior Cruciate Ligament Injuries , Anterior Cruciate Ligament Reconstruction/adverse effects , Humans , Knee Injuries/diagnostic imaging , Radiography
4.
Arch Orthop Trauma Surg ; 132(10): 1445-50, 2012 Oct.
Article in English | MEDLINE | ID: mdl-22678529

ABSTRACT

PURPOSE: To evaluate the impact of trauma-associated coagulation disorders on the neurological outcome in patients with traumatic epidural hematoma undergoing surgical or non-surgical treatment. A retrospective analysis was performed using prospectively collected data in a consecutive patient series from a level 1 trauma center. METHODS: Eighty-five patients with traumatic epidural hematoma were identified out of 1,633 patients admitted to our emergency room with traumatic head injuries between October 2004 and December 2008. The following prospectively assessed parameters were analyzed: Glasgow Coma Scale, coagulopathy, presence of skull fractures, additional injuries, the Injury Severity Score, hematoma volume and thickness at admission, hematoma volume progression over time and neurologic symptoms. Furthermore, patients were grouped based on whether they had undergone surgical or non-surgical treatment of the epidural hematoma. Clinical outcome was determined according to the Glasgow Outcome Score (GOS) at hospital discharge. RESULTS: Patients with coagulopathy showed significantly lower GOS values compared to patients with intact blood coagulation. Initial and progressive hematoma volumes did not influence neurological outcome. Patients with multiple injuries did not show a worse outcome compared to those with isolated epidural hematoma. There was no difference in patient's outcome after surgical or non-surgical treatment. CONCLUSIONS: Poor outcome after traumatic epidural hematoma was associated with coagulopathy. Progression of epidural hematoma volume was not associated with coagulopathy or with poor neurological outcome. Prospective studies are needed to confirm these results.


Subject(s)
Blood Coagulation Disorders/complications , Hematoma, Epidural, Cranial/complications , Hematoma, Epidural, Cranial/therapy , Adult , Female , Glasgow Outcome Scale , Hematoma, Epidural, Cranial/diagnostic imaging , Humans , Male , Middle Aged , Retrospective Studies , Tomography, X-Ray Computed , Treatment Outcome
5.
Oper Orthop Traumatol ; 24(2): 131-9, 2012 Apr.
Article in German | MEDLINE | ID: mdl-22373788

ABSTRACT

OBJECTIVE: Elimination of patellofemoral instability by reconstruction of the medial patellofemoral ligament (MPFL) with a gracilis autograft. INDICATIONS: Recurring lateral luxation and subluxation of the patella, tibial tuberosity-trochlear groove distance (TTTG) < 20 mm, persistent positive apprehension test in up to 45° of flexion, low grade trochlear dysplasia. CONTRAINDICATIONS: Traumatic luxation of the patella without anatomical risk factors, isolated treatment if TTTG > 20 mm, and isolated treatment for high-grade trochlear dysplasia (type B, C, D). SURGICAL TECHNIQUE: Supine postion. Stripping of the gracilis tendon. Drilling of two tunnels into the medial margin of the patella. Insertion of both tendon ends into the tunnels and fixation with resorbable screwlocks. Undermining of the fascia of the medial oblique vastus muscle and insertion of the tendon loop into the femoral point of insertion located at the medial epicondyle. Preparation of the femoral point of insertion and drilling of the femoral tunnel. Insertion of the graft into the femoral tunnel. Positioning of the knee in 30° of flexion. Positioning of the patella and fixation of the graft with a resorbable screw. POSTOPERATIVE MANAGEMENT: Two weeks of partial weight bearing. Knee orthesis for 6 weeks. Passive motion up to 60° of flexion for the first 2 weeks. Three weeks postoperatively unrestricted motion exercises, strengthening of the quadriceps muscle. Unlimited activity is possible 3 months postoperatively. RESULTS: The method presented in this manuscript was performed on 32 patients with recurring patellar luxation; 27 patients were available for clinical assessment at 1 year postoperatively. There were no recorded events of reluxation; the Kujala score increased on average from 61 points preoperatively to 93 points postoperatively.


Subject(s)
Joint Instability/surgery , Ligaments/surgery , Patellofemoral Joint/surgery , Plastic Surgery Procedures/instrumentation , Plastic Surgery Procedures/methods , Tendons/transplantation , Humans , Treatment Outcome
6.
Arch Orthop Trauma Surg ; 132(7): 975-84, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22431141

ABSTRACT

INTRODUCTION: The aim of this study was to present clinical experience and outcomes of intramedullary nailing of proximal, midshaft and distal tibia fractures with the Expert Tibia Nail (ETN; Synthes GmbH, Switzerland), an implant offering a wide range of proximal and distal locking options in multiple planes to increase stability of the implant and bone construct. PATIENTS AND METHODS: 180 patients with 185 tibia fractures were enclosed between July 2004 and May 2005 from ten trauma units (Levels I, II and III) and treated with intramedullary reamed and unreamed nailing with the ETN. Patients attended examinations at 12 weeks and 1 year. The occurrence of postoperative complications was documented as well as the outcomes of fracture healing, primary and secondary malalignment, implant failure, rate of infection and the need for reoperation. RESULTS: The 1-year follow-up rate was 81 %. At 1 year, the prevalence of delayed union was 12.2 % and higher for open fractures (18.2 %) compared to closed fractures (9.7 %). According to the fracture location, the percentage of delayed union was 5.9, 16.7 and 10.5 % in proximal third, midshaft and distal third cases, respectively. Patients with a plated fibula fracture had an eightfold higher risk of delayed union. The rate of malalignment >5° in any plane 1 year after surgery was 5.5 %. Proximal third fractures were at a higher risk of postoperative malalignment (17.6 %). The rate of secondary malalignment was 1.4 %. The risk of unplanned reoperation was 9.2 %. CONCLUSION: Intramedullary ETN fixation of tibia fractures results in low rates of delayed union, primary and secondary malalignment, implant-related complications, and secondary surgery. Fibula plating had a negative effect on the healing of the tibia.


Subject(s)
Bone Nails , Fracture Fixation, Intramedullary/instrumentation , Internal Fixators , Tibial Fractures/surgery , Adolescent , Adult , Aged , Aged, 80 and over , Bone Malalignment/epidemiology , Bone Malalignment/etiology , Female , Follow-Up Studies , Fractures, Ununited/epidemiology , Fractures, Ununited/etiology , Humans , Linear Models , Male , Middle Aged , Postoperative Complications/epidemiology , Prosthesis Failure , Reoperation/statistics & numerical data , Treatment Outcome , Young Adult
7.
Oper Orthop Traumatol ; 23(5): 397-410, 2011 Dec.
Article in German | MEDLINE | ID: mdl-22159844

ABSTRACT

OBJECTIVE: Restoration of axis, length, and rotation of the lower leg. Sufficient primary stability of the osteosynthesis for functional aftercare and to maintain joint mobility. Good bony healing in closed and open fractures. INDICATIONS: Closed and open fractures of the tibia and complete lower leg fractures distal to the isthmus (AO 42), extraarticular fractures of the distal tibia (AO 43 A1/A2/A3), segmental fractures of the tibia with a fracture in the distal tibia, and certain intraarticular fractures of the distal tibia without impression of the joint line with the use of additional implants (AO 43 C1) CONTRAINDICATIONS: Patient in reduced general condition (e.g., bed ridden), flexion of the knee of less than 90°, patients with knee arthroplasty of the affected leg, infection in the area of the nail's insertion, infection of the tibial cavity, complex articular fractures of the proximal or distal tibia with joint depression. SURGICAL TECHNIQUE: Closed reduction of the fracture preferably on a fracture table or using a distractor or an external fixation frame. If necessary, use pointed reduction clamps or sterile drapery. In some cases, additional implants like percutaneous small fragment screws, poller screws or k-wires are helpful. Open reduction is rarely necessary and must be avoided. Opening of the proximal tibia in line with the medullary canal. Canulated insertion of the Expert(TM) tibia nail (ETN; Synthes GmbH, Oberdorf, Switzerland) with reaming of the medullary canal. Control of axis, length, and rotation. Distal interlocking with the radiolucent drill and proximal interlocking with the targeting device. POSTOPERATIVE MANAGEMENT: Immediate mobilization of ankle and knee joint. Mobilization with 20 kg weight-bearing with crutches. X-ray control 6 weeks postoperatively and increased weight-bearing depending on the fracture status. In cases with simple fractures, good bony contact, or transverse fracture pattern, full weight-bearing at the end of week 6 is targeted. RESULTS: Between July 2004 and May 2005, 180 patients were included in a multicenter study. The follow-up rate was 81% after 1 year. Of these, 91 fractures (50.6%) were located in the distal third of the tibia. In this segment, the rate of delayed union was 10.6%. Malalignment of > 5° was observed in 5.4%. A secondary malalignment after initial good reduction was detected in only 1.1% of all cases. The implant-specific risk for screw breakage was 3.2%. One patient sustained a deep infection. If additional fibula plating was performed an 8-fold higher risk for delayed bone healing was observed (95%CI: 2.9-21.2, p< 0.001). If the fracture of the fibula was at the same height as on the tibia, the risk for delayed healing was even 14-fold (95% CI: 3.4-62.5, p< 0.001). Biomechanically plating of the fibula does not increase stability in suprasyndesmal distal tibia-fibular fractures treated with an intramedullary nail. Using the ETN with its optimized locking options, fibula plating is not recommended, thus, avoiding soft tissue problems and potentially delayed bone healing.


Subject(s)
Ankle Injuries/surgery , Bone Nails , Bone Plates , Fracture Fixation, Intramedullary/instrumentation , Fracture Fixation, Intramedullary/methods , Tibial Fractures/surgery , Adult , Aged , Aged, 80 and over , Ankle Injuries/diagnostic imaging , Female , Humans , Male , Middle Aged , Radiography , Tibial Fractures/diagnostic imaging , Treatment Outcome
8.
ScientificWorldJournal ; 11: 1206-15, 2011 Jun 09.
Article in English | MEDLINE | ID: mdl-21666990

ABSTRACT

Arts speech therapy (AST) is a therapeutic method within complementary medicine and has been practiced for decades for various medical conditions. It comprises listening and the recitation of different forms of speech exercises under the guidance of a licensed speech therapist. The aim of our study was to noninvasively investigate whether different types of recitation influence hemodynamics and oxygenation in the brain and skeletal leg muscle using near-infrared spectroscopy (NIRS). Seventeen healthy volunteers (eight men and nine women, mean age ± standard deviation 35.6 ± 12.7 years) were enrolled in the study. Each subject was measured three times on different days with the different types of recitation: hexameter, alliteration, and prose verse. Before, during, and after recitation, relative concentration changes of oxyhemoglobin (Δ[O2Hb]), deoxyhemoglobin (Δ[HHb]), total hemoglobin (Δ[tHb]), and tissue oxygenation saturation (StO2) were measured in the brain and skeletal leg muscle using a NIRS device. The study was performed with a randomized crossover design. Significant concentration changes were found during recitation of all verses, with mainly a decrease in Δ[O2Hb] and ΔStO2 in the brain, and an increase in Δ[O2Hb] and Δ[tHb] in the leg muscle during recitation. After the recitations, significant changes were mainly increases of Δ[HHb] and Δ[tHb] in the calf muscle. The Mayer wave spectral power (MWP) was also significantly affected, i.e., mainly the MWP of the Δ[O2Hb] and Δ[tHb] increased in the brain during recitation of hexameter and prose verse. The changes in MWP were also significantly different between hexameter and alliteration, and hexameter and prose. Possible physiological explanations for these changes are discussed. A probable reason is a different effect of recitations on the sympathetic nervous system. In conclusion, these changes show that AST has relevant effects on the hemodynamics and oxygenation of the brain and muscle.


Subject(s)
Brain/metabolism , Hemodynamics , Muscle, Skeletal/metabolism , Oxygen/metabolism , Adult , Female , Hemoglobins/analysis , Humans , Male , Middle Aged , Oxyhemoglobins/analysis , Spectroscopy, Near-Infrared , Speech Therapy
9.
Arch Orthop Trauma Surg ; 129(3): 359-62, 2009 Mar.
Article in English | MEDLINE | ID: mdl-18560857

ABSTRACT

INTRODUCTION: The 22nd Student World Winter Games took place in January 2005 in Innsbruck and Seefeld, Austria. Exactly 1,500 athletes of 50 nationalities competed in 69 events in ten winter sports. A total number of 750 functionaries, 800 volunteers and 85,000 spectators participated in the second largest winter sports event behind the Olympic winter games. AIM: The aim of this study was to evaluate the needed resources to ensure traumatological care for an event of that size. MATERIAL: At the medical "call-center" all consultations, as well as patient data, diagnosis, and medical treatment were recorded using a preset protocol. Further, all patients treated in the University Hospital Innsbruck were registered with an emphasis on trauma patients. RESULTS: Forty-eight of 65 patients transported to the hospital as a result of the Universiade were trauma patients, 37 of whom were athletes. The gender distribution was 34:14 (m:f). Ice hockey players had the highest rate of injury (25% of all injured athletes), followed by alpine skiers (20.8% of injured athletes). The highest ISS was nine. Forty-three patients got ambulatory treatment, five were admitted to the hospital and surgical treatment was conducted in three cases. Mean patient number was 4.8 per day. No additional personnel, structural, or technical hospital resources were needed to accommodate a large winter sports event like the Universiad. Thus, a level-B trauma center with an emergency room and independent traumatological department with around the clock surgical capability seems to be sufficient to provide traumatological care for an event of this size if the possibility of patient transport to a larger facility exists in the case of catastrophic events.


Subject(s)
Athletic Injuries/therapy , Emergency Medical Services/statistics & numerical data , Health Services Needs and Demand/statistics & numerical data , Trauma Centers/statistics & numerical data , Athletic Injuries/diagnosis , Austria , Female , Hospitals, University , Humans , Male
10.
Unfallchirurg ; 109(12): 1064-72, 2006 Dec.
Article in German | MEDLINE | ID: mdl-17109175

ABSTRACT

BACKGROUND: Traumatic facet dislocations and facet-fracture dislocations in the lower cervical spine (C2/C3 to C7/T1) are frequently associated with devastating neurological symptoms. A good outcome can only be achieved if the operator has wide and sound knowledge of reduction techniques and the best possible strategy is devised for the subsequent treatment of these severe lesions. PATIENTS AND METHODS: Between 1973 and 1997 a total of 117 of our patients met at least one of the following inclusion criteria: unilateral locked facet dislocation (48%), bilateral locked facet dislocations (23%), unilateral "perched" facet subluxation (14%), bilateral perched facet subluxation (12%), uni- or bilateral dislocation/perched subluxation with facet fractures (3%). RESULTS: Most of the lesions were located at the levels of C5/C6 and C6/7 (n=46 for each). Associated neurological deficits were present initially in 65% of patients: 35% had complete or incomplete spinal cord injuries (tetraplegia), 2% were paraplegic, and 28% had cervical radiculopathies. CONCLUSIONS: Closed reduction (e.g. with the aid of a halo ring) should be carried out as soon as possible after lower cervical spine dislocation or facet-fracture dislocation, as both the success rate of reduction and the potential for recovery from neurological deficits are clearly higher when reduction is achieved within the first 4 h after the initial injury.


Subject(s)
Cervical Vertebrae/injuries , Joint Dislocations/surgery , Spinal Fractures/surgery , Spinal Injuries/surgery , Adolescent , Adult , Aged , Cervical Vertebrae/surgery , Child , Female , Humans , Male , Middle Aged , Neurologic Examination , Paraplegia/etiology , Postoperative Complications/etiology , Quadriplegia/etiology , Radiculopathy/etiology , Recovery of Function , Spinal Cord Injuries/surgery
12.
Unfallchirurg ; 105(4): 353-8, 2002 Apr.
Article in German | MEDLINE | ID: mdl-12066474

ABSTRACT

Computer assisted navigation-based surgery is a novel and interesting challenge for todays surgeons. One must however keep in mind, that the indications for these techniques (a) should be carefully considered, (b) used only if morbidity is not increased and (c) when previously problematic or inacurate surgical methods can be improved upon. This study reports that, using a non-invasive fixation method (FISCOFIX-Cast), lesions between the ankle- and knee-joints can be precisely localized, registered and treated. Due to the difficult access to lesions especially in the posterior areas of the talus, using conventional arthroscopic methods this procedure is very useful. Percutaneous retrograde drilling (cf. [6, 7, 9, 15, 20, 21]) spared the joint's cartilage in all cases. At the level of the knee joint we see the usefulness of this method for complex situations (cf. [12, 13]) requiring precise drilling.


Subject(s)
Anterior Cruciate Ligament Injuries , Femur/surgery , Image Processing, Computer-Assisted/instrumentation , Imaging, Three-Dimensional , Knee Injuries/surgery , Osteochondritis Dissecans/surgery , Surgery, Computer-Assisted/instrumentation , Talus/surgery , Tibia/surgery , Tomography, X-Ray Computed/instrumentation , Anterior Cruciate Ligament/diagnostic imaging , Anterior Cruciate Ligament/surgery , Equipment Design , Femur/diagnostic imaging , Humans , Knee Injuries/diagnostic imaging , Osteochondritis Dissecans/diagnostic imaging , Sensitivity and Specificity , Talus/diagnostic imaging , Tibia/diagnostic imaging
13.
Orthopade ; 30(1): 59-65, 2001 Jan.
Article in German | MEDLINE | ID: mdl-11227354

ABSTRACT

Treatment principles of osteochondral lesions of the talus usually consist of debridement of the chondral part and methods that attempt to stimulate revascularization of the necrotic bony part of the lesion. The latter is mostly achieved through multiple drilling of the subchondral zone. Dorsomedial talar dome lesions are frequently inaccessible with antegrade drilling techniques. In addition, if the cartilage surface over the bony lesion is still intact, it can be injured by antegrade drilling. To overcome these potential problems, retrograde drilling techniques have been developed using drill guides or intraoperative fluoroscopy. Our proposed method of computer-assisted retrograde drilling is an advancement of these techniques. The use of 3D navigation provides the possibility for placing a guide wire exactly in the center of the lesion defined on preoperative MRI or CT scans. This guide wire can then be overreamed with cannulated reamers followed by retrograde bone grafting of the lesion or allows multiple retrograde drilling of the subchondral plate using a parallel drill guide. We found that computer-assisted retrograde drilling could improve precision, avoid misplacement of guide wires, and reduce the time of surgery and intraoperative fluoroscopy.


Subject(s)
Arthroscopy , Image Processing, Computer-Assisted/instrumentation , Imaging, Three-Dimensional/instrumentation , Osteochondritis Dissecans/surgery , Osteonecrosis/surgery , Talus/surgery , Bone Transplantation , Humans , Osteochondritis Dissecans/diagnostic imaging , Osteonecrosis/diagnostic imaging , Phantoms, Imaging , Radiography , Surgical Instruments , Talus/diagnostic imaging
14.
Radiology ; 218(1): 278-82, 2001 Jan.
Article in English | MEDLINE | ID: mdl-11152815

ABSTRACT

The authors developed a minimally invasive method with computer-assisted navigation for retrograde drilling of osteochondral lesions of the talus. Planning of the pathway and adjustment of the targeting device were performed outside the operating room. In 10 cadavers and four patients, accuracy of pin placement was in the range of 1.0-3.5 mm.


Subject(s)
Osteochondritis Dissecans/surgery , Talus , Adolescent , Adult , Equipment Design , External Fixators , Feasibility Studies , Female , Humans , Male , Osteochondritis Dissecans/diagnostic imaging , Tomography, X-Ray Computed
15.
Surg Endosc ; 14(8): 731-5, 2000 Aug.
Article in English | MEDLINE | ID: mdl-10954819

ABSTRACT

BACKGROUND: With an incidence rate of 2%, injury to the nerves of the lumbar plexus is the most common complication of laparoscopic hernioplasty, particularly when the transabdominal preperitoneal (TAPP) technique is used. METHODS: The course of the genitofemoral nerve, lateral femoral cutaneous nerve, and ilioinguinal nerve within the operation site was investigated in 53 adult dissecting-room bodies. Their relationship to the deep inguinal ring, iliopubic tract, and anterior superior iliac spine was also examined. RESULTS: Both the femoral and genital branches of the genitofemoral nerve may penetrate the abdominal wall lateral to the deep ring and cranial to the iliopubic tract. The lateral femoral cutaneous nerve and the ilioinguinal nerve may run immediately lateral to the anterior superior iliac spine. CONCLUSION: Contrary to the previously accepted opinion, dissection and the placement of staples either cranial to the iliopubic tract or lateral to the anterior superior iliac spine can result in injury to the nerves.


Subject(s)
Femoral Nerve/injuries , Hernia, Inguinal/surgery , Inguinal Canal/innervation , Intraoperative Complications , Adult , Humans , Inguinal Canal/anatomy & histology , Intraoperative Complications/prevention & control
16.
Eur J Biochem ; 254(2): 266-74, 1998 Jun 01.
Article in English | MEDLINE | ID: mdl-9660179

ABSTRACT

To determine its role in cell transformations, the v-src oncogene was introduced into the human foetal diploid fibroblasts MRC-5 and into MRC-SV1, a simian virus 40 (SV40)-transformed cell line derived from them. Infected cells were found to contain stably integrated intact proviruses, as determined by Southern blot analysis. Although highly expressed, v-src did not change the morphology or growth patterns of MRC-5 cells and failed to induce foci or alter their saturation densities. However, overexpression of v-src reduced the plating efficiencies of MRC-5 and induced anchorage-independent growth in a low but significant number of cells. Northern blot analysis showed that v-src selectively abolished the expression of decorin, a small dermatan/chondroitin sulphate proteoglycan that interacts with extracellular-matrix components and modulates collagen-fibril formation and the activity of transforming growth factor (TGF) beta1. Addition of herbimycin A, a potent pp60src tyrosine-kinase inhibitor, resulted in the reexpression of decorin in MRC-5 carrying v-src. There were no changes in the expressions of fibronectin, procollagen type I, or tissue plasminogen activator, an activator of extracellular-matrix-degrading enzymes. Moreover, v-src did not alter the expressions of the epidermal-growth-factor receptor or TGFbeta1 or reduce the growth-factor requirements of MRC-5 fibroblasts. MRC-5 and MRC-SV1 expressing v-src remained non-tumourigenic when injected into nude mice. Constitutive expression of v-src did not alter the mRNA levels of c-jun and junB, suggesting that the effects of the oncogene are not mediated by AP-1. Decorin gene expression has been shown previously to be maximal in quiescent cells and virtually absent in transformed ones. Our data indicate that the ability to synthesise decorin can be suppressed in human fibroblasts without their becoming transformed, and that the relations between decorin synthesis and growth controls need further clarification.


Subject(s)
Cell Division/drug effects , Genes, src , Proteoglycans/biosynthesis , Animals , Cell Adhesion , Cell Line, Transformed , Cell Transformation, Neoplastic/genetics , Cell Transformation, Viral/genetics , Decorin , Defective Viruses/genetics , Extracellular Matrix Proteins/genetics , Fibroblasts , Gene Expression , Humans , Mice , Proteoglycans/genetics , Proto-Oncogenes , RNA, Messenger/genetics , RNA, Messenger/metabolism , Retroviridae/genetics , Simian virus 40/genetics , Transforming Growth Factor beta/antagonists & inhibitors
18.
Int J Oncol ; 11(4): 717-25, 1997 Oct.
Article in English | MEDLINE | ID: mdl-21528266

ABSTRACT

Attempts were made to identify the cellular and molecular changes associated with SV40-transformation of human fibroblasts, MRC-5. SV40-transformed human fibroblasts, MRC-5V1, displayed a polygonal to round morphology, grew slowly, had reduced plating efficiencies but high saturation densities. However, they could be propagated in low serum-containing medium and grew very efficiently in soft agar. These altered growth properties of MRC-5V1 suggested that SV40 induced changes in cell adhesion and growth factor requirements. Indeed, MRC-5V1 expressed markedly reduced levels of cellular fibronectin, high levels of tPA and the expression of procollagen alpha 2(I) and decorin were absent. Moreover, MRC-5V1 did not express HGF/SF, a paracrine effector of epithelial cells and expressed very low levels of EGF receptor. However, SV40 induced the expression of TGF alpha, one of the ligands of the EGF receptor, TGF beta 1 and TGF beta 2, all of which are associated with cellular transformation. Given the establishment of autocrine loops in MRC-5V1 and the fact that decorin interacts with fibronectin and collagens and negatively regulates the activity of TGF beta s, these changes could account for the altered growth and transformation properties of MRC-5V1. Several studies have provided a link between oncogenic transformation, transcriptional and translational control. SV40 markedly reduced the expression of junB but not c-jun in MRC-5V1 and the expression of EIF-4E and EF1 delta were not significantly affected. The data shows that SV40-transformation of human fibroblasts is associated with multiple genetic changes affecting the expression of genes involved in cell adhesion, signal transduction and transcription, hence suggesting the breakdown of several cellular control mechanisms.

19.
Int J Oncol ; 11(5): 1071-80, 1997 Nov.
Article in English | MEDLINE | ID: mdl-21528305

ABSTRACT

c-erbB was introduced into normal human fibroblasts, MRC-5, which expressed normal levels of EGF receptor and in a SV40-transformed cell line, MRC-5V1, derived from them, which expressed markedly reduced levels of EGF receptor mRNA. MRC-5 overexpressing c-erbB, responded mitogenically to EGF. However, addition of high EGF concentrations markedly reduced DNA synthesis and resulted in the inhibition of cellular growth. In contrast, MRC-5V1 exhibited an increase in DNA synthesis in an EGF-dependent manner which was enhanced by overexpression of c-erbB. These cells, unlike MRC-5, also produced TGF alpha, an EGF receptor ligand which is often associated with cellular transformation. Ligand-activation of EGF receptor did not alter the lifespan, induce focus formation or anchorage-independence of MRC-5 and all the cell types remained non-tumourigenic in nude mice. However, c-erbB induced the expression of tPA, c-jun and junB in both MRC-5 and MRC-5V1. The data suggest that overexpression and activation of c-erbB is unlikely to play a role in immortalisation of human diploid fibroblasts but it may contribute to cellular transformation.

20.
Am J Occup Ther ; 49(8): 763-71, 1995 Sep.
Article in English | MEDLINE | ID: mdl-8526220

ABSTRACT

OBJECTIVES: This study examines the age-related increase of in-hand manipulation, the consistency of using a manipulation strategy, and the relationship between the frequency of in-hand manipulation and activities that typically require use of intrinsic hand control. METHOD: Children (N = 184) between 2 years and 7 years of age were observed during selected activities that could elicit three forms of in-hand manipulation: rotation, finger-to-palm translation, and palm-to-finger translation. The child's use of a manipulation strategy was recorded. Activities that required manipulation of objects including a spoon, buttons, and crayons were also observed. RESULTS: The study demonstrated that the frequency of two types of in-hand manipulation increases with age and illustrated the uneven nature of development of different types of in-hand manipulation. Even when the child had the ability, use of in-hand manipulation as a movement strategy was inconsistent. Small but significant relationships between in-hand manipulation skill and performance in selected activities were found when the effects of age were controlled. CONCLUSION: On a practical level, the findings raise questions as to whether maturity of in-hand manipulation may be a factor limiting performance in the everyday activities of typically developing children.


Subject(s)
Hand , Psychomotor Performance , Age Factors , Aging/physiology , Analysis of Variance , Child , Child Development/physiology , Child, Preschool , Hand/physiology , Humans , Motor Skills/physiology , Psychomotor Performance/physiology , Regression Analysis , Sampling Studies
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