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1.
Int J Oral Maxillofac Surg ; 48(9): 1235-1240, 2019 Sep.
Article in English | MEDLINE | ID: mdl-30878274

ABSTRACT

Standard bicycle helmets are designed to protect the cranial vault. Numerous studies have demonstrated the beneficial effect of standard bicycle helmets on craniocerebral trauma, but their protective effect on facial injuries remains unclear. Therefore, this study used data obtained by an accident research unit to investigate the protective effect of standard bicycle helmets on facial injuries. A total of 31,634 bicycle accidents were registered between 1999 and 2015; of these, 7004 met the study requirements. Demographic characteristics, technical information (relative collision speed, collision type, collision partner, helmet use), and clinical data (injury type) relating to these accidents were analyzed. Of all affected cyclists, 1005 (14.3%) had a facial injury (fracture and/or soft tissue injury). Bicycle helmets were worn in 11.8% of accidents. Of these, 75.4% involved males and 24.6% involved females. The bicycle helmet did not protect against facial injuries. Furthermore, sex and the type of collision partner were found to be risk factors for facial injuries. In the future, helmet designs should be modified to improve facial protection, and better education should be provided to the public regarding the benefits of bicycle helmets.


Subject(s)
Craniocerebral Trauma , Facial Injuries , Accidents, Traffic , Bicycling , Female , Head Protective Devices , Humans , Male
2.
Eur Spine J ; 28(Suppl 2): 13-17, 2019 06.
Article in English | MEDLINE | ID: mdl-29955999

ABSTRACT

OBJECTIVE: In 2013, we reported a case of combined anterior and posterior reconstruction after three-level en bloc vertebral body replacement and replacement of the aorta for chondrosarcoma of the thoracic spine. Eight years after, we observed an implant failure and now report on revision strategy and 2-year follow-up (f/u) after revision. METHODS: We report about the 2-year f/u of the same now 51-year-old gravedigger who needed to undergo revision surgery after implant failure. We did a combined anterior and posterior correction vertebral interbody fusion by (1) removal of broken screws in Th9 and L2, removal of broken titanium bars, correction of kyphosis, enhancement of the vertebral interbody fusion from Th8 to L4 using monoaxial titanium screws and cancellous bone transplantation and (2) removal of the broken plate and the loose cage, implantation of a novel expandable PEEK cage from Th11 to L1 and anterior stabilization from Th9/10 to L2/3, as well as autologous and allogeneic cancellous bone transplantation. RESULTS: Two years after revision surgery, the patient presented fully reintegrated without any complains. No painkillers needed to be taken. Pain was reported with 2 out of 10 on the VAS. CONCLUSION: Both procedures offer a good primary stabilization with excellent pain reduction and good return to life. Limited information on long-term survivors is known. Therefore, the theoretical advantage of a biological solution needs to be checked in the long-term f/u for consistency.


Subject(s)
Chondrosarcoma/surgery , Plastic Surgery Procedures , Spinal Fusion , Spinal Neoplasms/surgery , Thoracic Vertebrae/surgery , Aorta/surgery , Bone Plates , Bone Transplantation , Humans , Male , Middle Aged , Prosthesis Failure , Plastic Surgery Procedures/adverse effects , Plastic Surgery Procedures/instrumentation , Reoperation/instrumentation , Spinal Fusion/adverse effects , Spinal Fusion/instrumentation , Treatment Outcome
3.
PLoS One ; 12(4): e0175839, 2017.
Article in English | MEDLINE | ID: mdl-28422994

ABSTRACT

The EU Directive 2010/63/EU changed the requirements regarding the use of laboratory animals and raised important issues related to assessing the severity of all procedures undertaken on laboratory animals. However, quantifiable parameters to assess severity are rare, and improved assessment strategies need to be developed. Hence, a Sheep Grimace Scale (SGS) was herein established by observing and interpreting sheep facial expressions as a consequence of pain and distress following unilateral tibia osteotomy. The animals were clinically investigated and scored five days before surgery and at 1, 3, 7, 10, 14 and 17 days afterwards. Additionally, cortisol levels in the saliva of the sheep were determined at the respective time points. For the SGS, video recording was performed, and pictures of the sheep were randomized and scored by blinded observers. Osteotomy in sheep resulted in an increased clinical severity score from days 1 to 17 post-surgery and elevated salivary cortisol levels one day post-surgery. An analysis of facial expressions revealed a significantly increased SGS on the day of surgery until day 3 post-surgery; this elevated level was sustained until day 17. Clinical severity and SGS scores correlated positively with a Pearson´s correlation coefficient of 0.47. Further investigations regarding the applicability of the SGS revealed a high inter-observer reliability with an intraclass correlation coefficient of 0.92 and an accuracy of 68.2%. In conclusion, the SGS represents a valuable approach for severity assessment that may help support and refine a widely used welfare assessment for sheep during experimental procedures, thereby meeting legislation requirements and minimizing the occurrence of unrecognized distress in animal experimentation.


Subject(s)
Osteotomy , Pain Measurement/methods , Pain/diagnosis , Tibia/surgery , Animal Welfare , Animals , Facial Expression , Female , Hydrocortisone/analysis , Hydrocortisone/metabolism , Observer Variation , Pain/physiopathology , Pain/surgery , Postoperative Period , Reproducibility of Results , Saliva/chemistry , Sheep, Domestic , Tibia/innervation , Video Recording
4.
Unfallchirurg ; 119(5): 358-73, 2016 May.
Article in German | MEDLINE | ID: mdl-27178157

ABSTRACT

The clinical decision-making process for patients with severe trauma of the extremities for primary amputation or to initiate extensive reconstructive measures for limb salvage in the best interests of the patient can be complex and difficult. The many factors influencing the decision-making process, such as local anatomical, pathomechanical, physiological, psychosocial and general factors are demonstrated and discussed. In the past, the role of scores supporting the decision-making process for amputation or limb salvage has been overestimated. In the LEAP study it could clearly be demonstrated that none of the sometimes highly complex scores could fulfill the expectations to predict successful limb salvage or the need for amputation. In this article it is shown that initiators and authors of scores achieved much higher sensitivity and specificity in the inaugural studies compared to the standardized and controlled conditions used in the LEAP study. For a long time, a lack of feeling in the feet was considered a safe and reliable criterion for amputation but the LEAP study has made a substantial contribution to demythologizing this as a lead symptom. Patients with severe trauma of the ankle or foot requiring a free flap or ankle arthrodesis have a significantly worse outcome compared to patients with a below knee amputation. Taking all these influencing factors into consideration, a comprehensive algorithm is presented that facilitates, strengthens and standardizes decision-making for amputation or limb salvage. This algorithm consists of four modules: 1) decision-making, 2) emergency treatment, 3) definitive treatment and 4) fine tuning. In the decision-making module not only local and general injury severity are addressed but the expected result, the general condition, comorbidities, compliance and the will of the patient are also included.


Subject(s)
Algorithms , Amputation, Surgical/statistics & numerical data , Clinical Decision-Making/methods , Leg Injuries/epidemiology , Leg Injuries/surgery , Salvage Therapy/statistics & numerical data , Humans , Prevalence , Risk Factors , Treatment Outcome , United States/epidemiology
5.
Unfallchirurg ; 119(5): 400-7, 2016 May.
Article in German | MEDLINE | ID: mdl-27169849

ABSTRACT

Deciding between reconstruction and primary amputation after severe high-energy trauma to the lower extremities is difficult and consequential. The Lower Extremity Assessment Project (LEAP) prospectively included and investigated patients with severe, limb-threatening injuries below the femur, with third-grade open fractures, defined soft-tissue damage and amputation wounds. This paper aims to review the key results of the LEAP study, which were published in several parts, in due consideration of the newer relevant literature, and to deduce the consequences for clinical practice. The main results are as follows: No score is sufficiently reliable to predict the success of reconstruction. Loss of muscle seems to be more momentous than loss of bone. Any accompanying injuries that should be taken into account in the individual treatment concepts are crucial to the results, in addition to comorbidities and other individual patient-related factors, such as alcoholism, smoking, insurance, and social background. Psychological impairment is frequent after these injuries and should therefore be addressed regularly with regard to rehabilitation.


Subject(s)
Amputation, Surgical/rehabilitation , Amputation, Surgical/statistics & numerical data , Clinical Decision-Making/methods , Leg Injuries/epidemiology , Leg Injuries/therapy , Salvage Therapy/statistics & numerical data , Adolescent , Adult , Aged , Aged, 80 and over , Amputation, Surgical/psychology , Comorbidity , Evidence-Based Medicine , Female , Humans , Incidence , Leg Injuries/psychology , Male , Middle Aged , Risk Factors , Salvage Therapy/psychology , Treatment Outcome , United States/epidemiology , Young Adult
6.
Unfallchirurg ; 119(5): 414-20, 2016 May.
Article in German | MEDLINE | ID: mdl-27146807

ABSTRACT

Following severe lower extremity injury, the potential outcome of a salvage procedure might often be questionable. Objective criteria should help in decision-making. From the clinical practice of a level I trauma center, we demonstrate three case reports and approaches following severe lower extremity injury.


Subject(s)
Amputation Stumps , Amputation, Surgical/methods , Amputation, Surgical/rehabilitation , Leg Injuries/therapy , Salvage Therapy/instrumentation , Salvage Therapy/methods , Adult , Female , Humans , Leg Injuries/diagnosis , Trauma Severity Indices , Treatment Outcome
7.
Eur J Trauma Emerg Surg ; 42(5): 605-610, 2016 Oct.
Article in English | MEDLINE | ID: mdl-26438088

ABSTRACT

PURPOSE: Percutaneous dilatational tracheostomy (PDT) is a standard procedure routinely performed on intensive care units. While complication rates and long-term outcomes have been studied in different patient populations, there are few studies known to these authors involving PDT in trauma patients and the complications which may result. METHODS: Between March 2007 and August 2013, all instances and peri-procedural complications during PDT occurring on the trauma intensive care unit, a unit specialized in the care of injured patients and especially polytrauma patients, were documented. PDTs were performed by a surgeon with the assistance and supervision of another, using bronchoscopic guidance performed by the respiratory medicine department. RESULTS: 289 patients were included in the study, 225 men and 64 women with a mean age of 49 ± 21 years. Complications occurred in 37.4 % of cases. The most common complication, bleeding, occurred in 26.3 % of patients ranging from little to severe bleeding. Fracture of tracheal cartilage occurred in 6 % of PDT cases. Additional complications such as dislocation of the guidewire, hypotension, and oxygen desaturation were observed. Most complications did not require treatment. The second tracheal intercartilaginous space was successfully intubated in 82 % of cases. CONCLUSIONS: PDT is a safe procedure in trauma patients. When considering the severity of complications such as major blood loss, pneumothorax, or death, this evidence suggests that PDT is safer in trauma patients compared to other patient cohorts.


Subject(s)
Bronchoscopy/methods , Critical Illness , Intensive Care Units , Trachea/injuries , Tracheostomy , Critical Illness/therapy , Dilatation , Female , Humans , Male , Middle Aged , Patient Safety , Practice Guidelines as Topic , Tracheostomy/instrumentation , Tracheostomy/methods , Ventilator Weaning
8.
Z Orthop Unfall ; 154(2): 128-33, 2016 Apr.
Article in German | MEDLINE | ID: mdl-26670303

ABSTRACT

Sagittal deformities of the spine frequently result in back pain, as patients have to expend much energy in compensation. The sagittal alignment of the spine is defined by its curvatures (lordosis and kyphosis) relative to the position of the pelvis. Diagnostic assessment is based on full spine a. p. and lateral X-rays. The sagittal balance is primarily described by different angles that can be measured, e.g. lumbar lordosis, pelvic incidence, pelvic tilt and thoracic kyphosis. The quality of life can best be estimated by subtracting lumbar lordosis from the pelvic incidence. However, initial evaluation of the sagittal balance can also be based on the sagittal vertical axis. The severity of imbalance can be described by the sagittal vertical axis and the pelvic tilt, but surgical therapy necessitates a more profound analysis, which can be based on the SRS-Schwab classification.


Subject(s)
Anatomic Landmarks/diagnostic imaging , Patient Positioning/methods , Radiography/methods , Spinal Curvatures/diagnostic imaging , Spine/abnormalities , Spine/diagnostic imaging , Diagnosis, Differential , Humans , Radiographic Image Interpretation, Computer-Assisted/methods , Reproducibility of Results , Sensitivity and Specificity
10.
Unfallchirurg ; 114(1): 9-16, 2011 Jan.
Article in German | MEDLINE | ID: mdl-21246343

ABSTRACT

This paper gives recommendations for treatment of thoracolumbar and lumbar spine injuries. The recommendations are based on the experience of the involved spine surgeons, who are part of a study group of the "Deutsche Gesellschaft für Unfallchirurgie" and a review of the current literature. Basics of diagnostic, conservative, and operative therapy are demonstrated. Fractures are evaluated by using morphologic criteria like destruction of the vertebral body, fragment dislocation, narrowing of the spinal canal, and deviation from the individual physiologic profile. Deviations from the individual sagittal profile are described by using the monosegmental or bisegmental end plate angle. The recommendations are developed for acute traumatic fractures in patients without severe osteoporotic disease.


Subject(s)
Lumbar Vertebrae/injuries , Lumbar Vertebrae/surgery , Spinal Fusion/standards , Spinal Injuries/therapy , Thoracic Vertebrae/injuries , Thoracic Vertebrae/surgery , Vertebroplasty/standards , Germany , Humans , Minimally Invasive Surgical Procedures/standards , Practice Guidelines as Topic
11.
Z Orthop Unfall ; 148(5): 573-8, 2010 Sep.
Article in German | MEDLINE | ID: mdl-20645253

ABSTRACT

AIM: Quads or all-terrain vehicles do not seem to play a major role either in traffic accidents or in hospital admissions in Germany. However, reports about spectacular quad crashes in the press are not that infrequent. In contrast, no scientific survey or study regarding the issue of quad crashes in Germany has been published so far. Thus, this study aims to evaluate the present incidence of quad crashes, accident circumstances and resulting injury patterns, and to discuss possible consequences. METHOD: At a level I trauma centre, data from accident and hospital records of quad drivers were analysed focusing on the following parameters: injury type, localisation and mechanism, treatment details, abbreviated injury scale (AIS) score, maximum AIS (MAIS) score, delta-v, collision speed, and other technical parameters. Comparisons to motorcycle accidents were performed. RESULT During a five-year period from 2005 to 2009, there were ten admissions of quad drivers out of around 11 000 emergency trauma patients (0.1 %). Five accidents had happened off-road, four were traffic accidents. Eight patients were male; the mean age was 30 years. The mean total hospital stay was 15 days; there was a mean of 1.5 stays per patients with 2.0 surgical procedures needed. One patient died, only two recovered fully. The accident research data bank revealed 14 cases of quad accidents out of 18 990 (0.1 %). The mean impact velocity was 35 km/h (motorcyclists 40.0 km/h). The most frequent injury mechanism was a collision with a car. The upper extremity was the predominant injured region (AIS 0.7), while it was the lower extremity for motorcyclists (AIS0.91). The maximum AIS were 1.4 in quad drivers and 1.49 in motorcyclists. CONCLUSIONS: Although the absolute incidence of quad accidents in Germany is low, they pose a relatively high risk for severe injuries. Possible reasons are the comparatively low active and passive safety of quads as well as limited experience with quad driving and the "fun" aspect which might provoke risky driving behaviour. Larger series from the US report a high incidence of drug abuse among quad casualties as well as very limited use of helmets. In Germany, helmet usage has been mandatory since 2006. Possible additional measures to prevent a rise in quad accidents could be the total prohibition of alcohol consumption for quad drivers as well as special courses or driving licenses or an increase of the legal age for driving quads.


Subject(s)
Accidents, Traffic/statistics & numerical data , Off-Road Motor Vehicles/statistics & numerical data , Wounds and Injuries/epidemiology , Adolescent , Adult , Age Distribution , Female , Germany/epidemiology , Humans , Male , Prevalence , Risk Assessment , Risk Factors , Young Adult
12.
Orthopade ; 39(4): 417-24, 2010 Apr.
Article in German | MEDLINE | ID: mdl-20232195

ABSTRACT

Vertebral compression fractures are among the most common forms of manifestations of osteoporosis. Conservative treatment comprises adequate analgesia, osteoporosis medication and individualized physiotherapy or braces. Nevertheless, vertebral compression fractures frequently lead to persisting pain and decrease daily activity and quality of life. In these cases, kyphoplasty and vertebroplasty can be efficient treatment options. Vertebroplasty is a minimally invasive procedure, in which bone cement is filled into the vertebral body under fluoroscopic control. In most cases, this internal stabilization leads to a rapid reduction in pain. Kyphoplasty additionally aims to correct the kyphotic deformation of the broken vertebra via introducing and inflating a balloon catheter. There is broad clinical experience with both procedures. For kyphoplasty, randomized controlled trials showed significant improvements in pain and quality of life in patients undergoing kyphoplasty. However, cement leakages lead to rare but severe complications such as pulmonary embolism and nerve palsies.


Subject(s)
Fractures, Compression/surgery , Fractures, Spontaneous/surgery , Osteoporosis/surgery , Spinal Diseases/surgery , Spinal Fractures/surgery , Vertebroplasty/instrumentation , Vertebroplasty/methods , Aged, 80 and over , Bone Cements/adverse effects , Braces , Equipment Design , Evidence-Based Medicine , Extravasation of Diagnostic and Therapeutic Materials/etiology , Female , Fractures, Compression/diagnostic imaging , Fractures, Spontaneous/diagnostic imaging , Humans , Kyphosis/diagnostic imaging , Kyphosis/surgery , Lumbar Vertebrae/diagnostic imaging , Lumbar Vertebrae/injuries , Lumbar Vertebrae/surgery , Osteoporosis/diagnostic imaging , Pain Measurement , Physical Therapy Modalities , Postoperative Complications/diagnostic imaging , Postoperative Complications/etiology , Pulmonary Embolism/etiology , Quality of Life , Randomized Controlled Trials as Topic , Recurrence , Reoperation , Spinal Diseases/diagnostic imaging , Spinal Fractures/diagnostic imaging , Thoracic Vertebrae/diagnostic imaging , Thoracic Vertebrae/injuries , Thoracic Vertebrae/surgery , Tomography, X-Ray Computed , Treatment Outcome
13.
Z Orthop Unfall ; 146(6): 747-53, 2008.
Article in German | MEDLINE | ID: mdl-19085724

ABSTRACT

AIM: Novice drivers are at high risk for crash involvement. We performed an analysis of causations, injury patterns and distributions of novice drivers in cars and on motorcycles in road traffic as a basis for proper measurements. METHOD: Data of accident and hospital records of novice drivers (licence < 2 years) were analysed focusing on the following parameters: injury type, localisation and mechanism, abbreviated injury scale (AIS), maximum AIS (MAIS), delta-v, collision speed and other technical parameters and compared with those of experienced drivers. RESULTS: In 18 352 accidents in the area of Hannover (years 1985-2004), 2602 novice drivers and 18 214 experienced drivers were recorded as having an accident. Novice car drivers were more often and more severely injured whereas on motorcycles the experienced drivers were at higher risk. Novice drivers of both groups sustained more often extremity injuries. 4.5 % of the novice car drivers were not restrained by seatbelts as compared to 3.7 % of the experienced drivers and 6.1 % of the novice motorcycle drivers did not wear a proper helmet (versus 6.5 %). Severe injuries were sustained in 20 % at collision speeds below 30 km/h and in 80 % at collision speeds above 50 km/h. Novice car drivers drove significantly older cars. The risk profile of novice drivers is similar to that of drivers older than 65. CONCLUSION: Structural protection and special lectures like skidding courses could be proper measurements next to harder punishment of violations.


Subject(s)
Accidents, Traffic/statistics & numerical data , Automobile Driving/education , Automobiles/statistics & numerical data , Motorcycles/statistics & numerical data , Wounds and Injuries/epidemiology , Abbreviated Injury Scale , Adolescent , Adult , Age Factors , Automobile Driving/statistics & numerical data , Causality , Cross-Sectional Studies , Female , Germany , Head Protective Devices/statistics & numerical data , Humans , Incidence , Male , Prospective Studies , Seat Belts/statistics & numerical data , Sex Factors , Utilization Review/statistics & numerical data , Young Adult
14.
Chirurg ; 79(10): 918, 920-6, 2008 Oct.
Article in German | MEDLINE | ID: mdl-18719864

ABSTRACT

Spinal trauma poses considerable threats to survival and quality of life. Especially cervical spine injuries are often associated with neurologic deficits. A thorough diagnostic pathway, often including computed tomography with sagittal reconstruction, is mandatory to evaluate the extent and consequences of spinal trauma. Every treatment must aim to restore stability and prevent secondary neurologic deterioration. Compression fractures usually can be treated successfully with conservative treatment, while burst fractures usually, and flexion/distraction injuries, and fracture-dislocation generally require internal stabilization. Injuries of the upper cervical spine can be treated conservatively or operatively, depending on the degree of instability. In the lower cervical spine, most injuries require internal fixation.


Subject(s)
Spinal Fractures/surgery , Spinal Fusion , Cervical Vertebrae/injuries , Cervical Vertebrae/surgery , Female , Humans , Joint Dislocations/diagnosis , Joint Dislocations/surgery , Lumbar Vertebrae/injuries , Lumbar Vertebrae/surgery , Middle Aged , Multiple Trauma/diagnosis , Multiple Trauma/surgery , Osteoporosis, Postmenopausal/complications , Osteoporosis, Postmenopausal/diagnosis , Osteoporosis, Postmenopausal/surgery , Postoperative Complications/diagnosis , Postoperative Complications/surgery , Prosthesis Implantation , Reoperation , Spinal Fractures/diagnosis , Spinal Fractures/etiology , Thoracic Vertebrae/injuries , Thoracic Vertebrae/surgery , Tomography, X-Ray Computed
15.
Unfallchirurg ; 109(11): 977-82; quiz 983, 2006 Nov.
Article in German | MEDLINE | ID: mdl-17021900

ABSTRACT

While tetanus is a rare disease in industrialized countries, this infectious disease is still responsible for up to 1,000,000 deaths per year in the developing world. In Germany, the introduction of a country-wide vaccination program (STIKO) has led to a decrease in the frequency of tetanus infection from 115 cases per year in the 1960s to fewer than 15 cases per year in the years from 1990 to 2000. In spite of all the treatment now available, tetanus infection still has a lethal outcome in up to 40% of cases. The Robert-Koch Institute recommends active or passive vaccination depending on the wound classification and the patient's current vaccination status. Since when patients have multiple trauma the emphasis while they are being treated for shock is on stabilisation and diagnosis, there is a real risk of underestimating the size and the level of contamination of existing wounds. Since it is not possible to ascertain the patient's vaccination status in most cases, we recommend simultaneous immunization of polytraumatized patients with skin lesions using Tetanol-Tetagam early in the course of the diagnostic procedures while the patients are still in the emergency room.


Subject(s)
Emergency Service, Hospital , Immunization Programs , Multiple Trauma/complications , Tetanus Toxoid/administration & dosage , Tetanus/prevention & control , Algorithms , Humans , Immunization, Secondary , Practice Guidelines as Topic , Risk Factors , Tetanus/diagnosis , Tetanus Antitoxin/administration & dosage
16.
Orthopade ; 33(1): 6-12, 2004 Jan.
Article in German | MEDLINE | ID: mdl-14747905

ABSTRACT

Vertebroplasty and Kyphoplasty represent minimal-invasive techniques for cement augmentation of vertebral bodies. Both procedures are successfully used for pain-relieving stabilizations of osteoporotic fractures or malignant processes. Advantages of kyphoplasty over vertebroplasty are to be seen in the possibility of deformity correction as well as in a decreased risk of cement extrusions which represent the most important potential for clinical complications. Long-term experiences with the effect of cementing are sparse. Thus it seems even more important, to judge indications and possibilities realistically. The decision whether and when to perform an augmentation is influenced by multiple factors. These include age of the patient, age of the fracture, degree of deformation and further degenerative changes of the spine. This article summarizes the present research and literature und is thought to provide guidelines for the aforementioned decision making processes.


Subject(s)
Bone Cements , Hemangioma/surgery , Orthopedic Procedures , Osteoporosis/complications , Polymethyl Methacrylate/administration & dosage , Spinal Fractures/surgery , Spinal Neoplasms/surgery , Spine/surgery , Age Factors , Bone Cements/therapeutic use , Chronic Disease , Discitis/diagnosis , Female , Follow-Up Studies , Fractures, Spontaneous/etiology , Fractures, Spontaneous/surgery , Hemangioma/diagnosis , Humans , Kyphosis/etiology , Kyphosis/surgery , Magnetic Resonance Imaging , Middle Aged , Minimally Invasive Surgical Procedures , Orthopedic Procedures/methods , Osteoporosis/diagnosis , Osteoporosis/diagnostic imaging , Risk Factors , Spinal Fractures/diagnosis , Spinal Fractures/diagnostic imaging , Spinal Fractures/etiology , Spinal Neoplasms/diagnosis , Spinal Neoplasms/secondary , Time Factors , Tomography, X-Ray Computed
17.
EMBO J ; 20(22): 6180-90, 2001 Nov 15.
Article in English | MEDLINE | ID: mdl-11707390

ABSTRACT

IkappaB proteins associate with the transcription factor NF-kappaB via their ankyrin repeat domain. Bcl-3 is an unusual IkappaB protein because it is primarily nucleoplasmic and can lead to enhanced NF-kappaB-dependent transcription, unlike the prototypical IkappaB protein IkappaBalpha, which inhibits NF-kappaB activity by retaining it in the cytoplasm. Here we report the 1.9 A crystal structure of the ankyrin repeat domain of human Bcl-3 and compare it with that of IkappaBalpha bound to NF-kappaB. The two structures are highly similar over the central ankyrin repeats but differ in the N-terminal repeat and at the C-terminus, where Bcl-3 contains a seventh repeat in place of the acidic PEST region of IkappaBalpha. Differences between the two structures suggest why Bcl-3 differs from IkappaBalpha in selectivity towards various NF-kappaB species, why Bcl-3 but not IkappaBalpha can associate with its NF-kappaB partner bound to DNA, and why two molecules of Bcl-3 but only one of IkappaBalpha can bind to its NF-kappaB partner. Comparison of the two structures thus provides an insight into the functional diversity of IkappaB proteins.


Subject(s)
Ankyrins/chemistry , I-kappa B Proteins , Proto-Oncogene Proteins/chemistry , Amino Acid Sequence , B-Cell Lymphoma 3 Protein , Binding Sites , Crystallography, X-Ray , Cytoplasm/metabolism , DNA-Binding Proteins/chemistry , Humans , Models, Biological , Models, Molecular , Molecular Sequence Data , NF-KappaB Inhibitor alpha , NF-kappa B/chemistry , Protein Structure, Secondary , Protein Structure, Tertiary , Repetitive Sequences, Amino Acid , Sequence Homology, Amino Acid , Transcription Factors
18.
J Mol Biol ; 309(1): 1-18, 2001 May 25.
Article in English | MEDLINE | ID: mdl-11491282

ABSTRACT

ARM and HEAT motifs are tandemly repeated sequences of approximately 50 amino acid residues that occur in a wide variety of eukaryotic proteins. An exhaustive search of sequence databases detected new family members and revealed that at least 1 in 500 eukaryotic protein sequences contain such repeats. It also rendered the similarity between ARM and HEAT repeats, believed to be evolutionarily related, readily apparent. All the proteins identified in the database searches could be clustered by sequence similarity into four groups: canonical ARM-repeat proteins and three groups of the more divergent HEAT-repeat proteins. This allowed us to build improved sequence profiles for the automatic detection of repeat motifs. Inspection of these profiles indicated that the individual repeat motifs of all four classes share a common set of seven highly conserved hydrophobic residues, which in proteins of known three-dimensional structure are buried within or between repeats. However, the motifs differ at several specific residue positions, suggesting important structural or functional differences among the classes. Our results illustrate that ARM and HEAT-repeat proteins, while having a common phylogenetic origin, have since diverged significantly. We discuss evolutionary scenarios that could account for the great diversity of repeats observed.


Subject(s)
Evolution, Molecular , Proteins/chemistry , Repetitive Sequences, Amino Acid , Amino Acid Motifs , Amino Acid Sequence , Animals , Computational Biology , Databases as Topic , Humans , Models, Molecular , Molecular Sequence Data , Phylogeny , Protein Conformation , Proteins/classification
20.
Curr Opin Struct Biol ; 11(1): 26-32, 2001 Feb.
Article in English | MEDLINE | ID: mdl-11179888

ABSTRACT

During the past year, much progress has been made in understanding the structural basis of transcriptional regulation. Low-resolution electron microscopy structures of general transcription factor complexes have shed light on their global organization. These results are complemented by the structural and biochemical analysis of individual general transcription factors. High-resolution crystal structures of sequence-specific transcription factors still yield unexpected results. Detailed analysis of DNA recognition by different family members of the same class of sequence-specific transcription factors shows considerable variations in the way they interact with DNA.


Subject(s)
DNA-Binding Proteins/chemistry , Transcription Factors/chemistry , Binding Sites , Crystallography, X-Ray , DNA-Binding Proteins/metabolism , Helix-Turn-Helix Motifs , Immunoglobulins/chemistry , Microscopy, Electron , Models, Molecular , Nuclear Magnetic Resonance, Biomolecular , Protein Conformation , Transcription Factors/metabolism
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