Comparison of veterinarians and a deep learning tool in the diagnosis of equine ophthalmic diseases

BACKGROUND/OBJECTIVES

The aim was to compare ophthalmic diagnoses made by veterinarians to a deep learning (artificial intelligence) software tool which was developed to aid in the diagnosis of equine ophthalmic diseases. As equine ophthalmology is a very specialised field in equine medicine, the tool may be able to help in diagnosing equine ophthalmic emergencies such as uveitis.

STUDY DESIGN

In silico tool development and assessment of diagnostic performance.

METHODS

A deep learning tool which was developed and trained for classification of equine ophthalmic diseases was tested with 40 photographs displaying various equine ophthalmic diseases. The same data set was shown to different groups of veterinarians (equine, small animal, mixed practice, other) using an opinion poll to compare the results and evaluate the performance of the programme. Convolutional Neural Networks (CNN) were trained on 2346 photographs of equine eyes, which were augmented to 9384 images. Two hundred and sixty-one separate unmodified images were used to evaluate the trained network. The trained deep learning tool was used on 40 photographs of equine eyes (10 healthy, 12 uveitis, 18 other diseases). An opinion poll was used to evaluate the diagnostic performance of 148 veterinarians in comparison to the software tool.

RESULTS

The probability for the correct answer was 93% for the AI programme. Equine veterinarians answered correctly in 76%, whereas other veterinarians reached 67% probability for the correct diagnosis.

MAIN LIMITATIONS

Diagnosis was solely based on images of equine eyes without the possibility to evaluate the inner eye.

CONCLUSIONS

The deep learning tool proved to be at least equivalent to veterinarians in assessing ophthalmic diseases in photographs. We therefore conclude that the software tool may be useful in detecting potential emergency cases. In this context, blindness in horses may be prevented as the horse can receive accurate treatment or can be sent to an equine hospital. Furthermore, the tool gives less experienced veterinarians the opportunity to differentiate between uveitis and other ocular anterior segment disease and to support them in their decision-making regarding treatment.

Infrapatellar Fat Pad Modulates Osteoarthritis-Associated Cytokine and MMP Expression in Human Articular Chondrocytes

Osteoarthritis (OA) most frequently affects the knee joint and is associated with an elevated expression of cytokines and extracellular cartilage matrix (ECM), degrading enzymes such as matrix metalloproteinases (MMPs). Differences in gene expression of the intra-articularly located infrapatellar fat pad (IPFP) and other fatty tissue suggest its autonomous function, yet its role in OA pathogenesis remains unknown. Human IPFPs and articular cartilage were collected from OA patients undergoing total knee arthroplasty, and biopsies from the IPFP of healthy patients harvested during knee arthroscopy served as controls (CO). Isolated chondrocytes were co-cultured with either osteoarthritic (OA) or CO-IPFPs in a transwell system. Chondrocyte expression of MMP1, -3, -13, type 1 and 2 collagens, interleukin IL1β, IL6, IL10, and tumor necrosis factor TNFα was analyzed by RTD-PCR at day 0 and day 2, and TNFα secretion was analyzed by ELISA. The cytokine release in IPFPs was assessed by an array. Results: Both IPFPs (CO, OA) significantly reduced the expression of type 2 collagen and TNFα in chondrocytes. On the other hand, only CO-IPFP suppressed the expression of type 1 collagen and significantly induced the MMP13 expression. On the contrary, IL1β and IL6 were significantly induced when exposed to OA-IPFP. Conclusions: The partial loss of the suppressive effect on type 1 collagen gene expression found for OA-IPFP shows the pathological remodeling and dedifferentiation potential of the OA-IPFP on the chondrocytes. However, the significant suppression of TNFα implies that the OA- and CO-IPFP could also exhibit a protective role in the knee joint, preventing the progress of inflammation.

Enhancing physical activity and reducing symptoms of patients with osteoarthritis of the knee: a randomized controlled trial of the PrevOP-Psychological Adherence Program

BACKGROUND

This primary analysis evaluated the "PREVenting the impairment of primary Osteoarthritis by high-impact long-term Physical exercise regimen-Psychological Adherence Program" (PrevOP-PAP), designed to support patients with osteoarthritis of the knee (OAK) to engage in regular moderate-to-vigorous physical activity (MVPA) to reduce OAK symptoms (WOMAC scores). Theory-based on the health action process approach (HAPA), the intervention targeted volitional precursors of MVPA change: action and coping planning, maintenance and recovery self-efficacy, action control, and social network formation. We hypothesized that compared to an active control condition, increases in MVPA at the end of the 12-month intervention would translate into lower WOMAC scores at 24 months in the intervention condition.

METHODS

Participants with radiographically verified moderate OAK (N = 241; 62.66% female; M(SD) = 65.60(7.61) years) were randomly assigned to the intervention (51%) or the active control condition. WOMAC scores (24 months) were the primary -, accelerometer-assessed MVPA (12 months) the key secondary outcomes. The PrevOP-PAP was a 12-month intervention with computer-assisted face-to-face and phone-based sessions designed to increase HAPA-proposed volitional precursors of MVPA change (up to 24 months; secondary outcomes). Intent-to-treat analyses included multiple regression and manifest path models.

RESULTS

MVPA (12 months) did not mediate effects of the PrevOP-PAP on WOMAC scores (24 months). Compared to the active control condition, WOMAC scores (24 months) were lower in the intervention condition, but this effect did not remain stable in sensitivity analyses (b(SE) = -8.41(4.66), 95%-CI [-17.53; 0.71]). However, exploratory analyses revealed significantly stronger reductions in WOMAC-pain (24 months) in the intervention condition (b(SE) = -2.99(1.18), 95%-CI [-5.36; -0.63]). Groups did not differ in MVPA at 12 months (b(SE) = -3.78(3.42), 95%-CI [-10.80; 2.58]). Of the proposed precursors of MVPA change, action planning was higher in the intervention than in the control condition (24 months; b(SE) = 0.64(0.26), 95%-CI [0.14; 1.15]).

CONCLUSIONS

Compared to an active control condition, the PrevOP-PAP did not produce reliable effects on WOMAC scores and none on preceding MVPA. Of the HAPA-proposed volitional precursors, only action planning was sustainably increased. Future interventions should use m-health applications to digitally support long-term changes in proposed volitional precursors of MVPA change.

TRIAL REGISTRATION

German Clinical Trials Register; https://drks.de/search/de/trial/DRKS00009677 ; also available at http://apps.who.int/trialsearch/ ; registration number: DRKS00009677; date of registration: 26/01/2016.

The spinal cord injury-induced immune deficiency syndrome: results of the SCIentinel study

Infections are prevalent after spinal cord injury (SCI), constitute the main cause of death and are a rehabilitation confounder associated with impaired recovery. We hypothesize that SCI causes an acquired lesion-dependent (neurogenic) immune suppression as an underlying mechanism to facilitate infections. The international prospective multicentre cohort study (SCIentinel; protocol registration DRKS00000122; n = 111 patients) was designed to distinguish neurogenic from general trauma-related effects on the immune system. Therefore, SCI patient groups differing by neurological level, i.e. high SCI [thoracic (Th)4 or higher]; low SCI (Th5 or lower) and severity (complete SCI; incomplete SCI), were compared with a reference group of vertebral fracture (VF) patients without SCI. The primary outcome was quantitative monocytic Human Leukocyte Antigen-DR expression (mHLA-DR, synonym MHC II), a validated marker for immune suppression in critically ill patients associated with infection susceptibility. mHLA-DR was assessed from Day 1 to 10 weeks after injury by applying standardized flow cytometry procedures. Secondary outcomes were leucocyte subpopulation counts, serum immunoglobulin levels and clinically defined infections. Linear mixed models with multiple imputation were applied to evaluate group differences of logarithmic-transformed parameters. Mean quantitative mHLA-DR [ln (antibodies/cell)] levels at the primary end point 84 h after injury indicated an immune suppressive state below the normative values of 9.62 in all groups, which further differed in its dimension by neurological level: high SCI [8.95 (98.3% confidence interval, CI: 8.63; 9.26), n = 41], low SCI [9.05 (98.3% CI: 8.73; 9.36), n = 29], and VF without SCI [9.25 (98.3% CI: 8.97; 9.53), n = 41, P = 0.003]. Post hoc analysis accounting for SCI severity revealed the strongest mHLA-DR decrease [8.79 (95% CI: 8.50; 9.08)] in the complete, high SCI group, further demonstrating delayed mHLA-DR recovery [9.08 (95% CI: 8.82; 9.38)] and showing a difference from the VF controls of -0.43 (95% CI: -0.66; -0.20) at 14 days. Complete, high SCI patients also revealed constantly lower serum immunoglobulin G [-0.27 (95% CI: -0.45; -0.10)] and immunoglobulin A [-0.25 (95% CI: -0.49; -0.01)] levels [ln (g/l × 1000)] up to 10 weeks after injury. Low mHLA-DR levels in the range of borderline immunoparalysis (below 9.21) were positively associated with the occurrence and earlier onset of infections, which is consistent with results from studies on stroke or major surgery. Spinal cord injured patients can acquire a secondary, neurogenic immune deficiency syndrome characterized by reduced mHLA-DR expression and relative hypogammaglobulinaemia (combined cellular and humoral immune deficiency). mHLA-DR expression provides a basis to stratify infection-risk in patients with SCI.

A rare case of severely elevated septic parameters caused by intercurrent juvenile rheumatoid arthritis despite dual trauma surgery

Procalcitonin (PCT) and C-reactive protein (CRP) are considered markers used in clinical practice to differentiate bacterial infections from autoimmune origin. Here we evaluate a rare case of a male patient diagnosed with juvenile idiopathic arthritis. The patient presented repeatedly to our department with atraumatic femoral head necrosis, traumatic medial femoral neck fracture and peri-implant femoral fracture. While undergoing repeated surgical interventions including a removal of osteosynthesis material and total endoprosthesis of his right hip including double subtrochanteric osteotomy, the patient developed drastically increasing infection parameters of PCT and CRP. After a completely inconspicuous revision we revealed the untypical genesis of a rheumatic cause. Consequently, we emphasize this etiology to be considered in further decision making for trauma surgery.

Artificial intelligence as a tool to aid in the differentiation of equine ophthalmic diseases with an emphasis on equine uveitis

BACKGROUND

Due to recent developments in artificial intelligence, deep learning, and smart-device-technology, diagnostic software may be developed which can be executed offline as an app on smartphones using their high-resolution cameras and increasing processing power to directly analyse photos taken on the device.

OBJECTIVES

A software tool was developed to aid in the diagnosis of equine ophthalmic diseases, especially uveitis.

STUDY DESIGN

Prospective comparison of software and clinical diagnoses.

METHODS

A deep learning approach for image classification was used to train software by analysing photographs of equine eyes to make a statement on whether the horse was displaying signs of uveitis or other ophthalmic diseases. Four basis networks of different sizes (MobileNetV2, InceptionV3, VGG16, VGG19) with modified top-layers were evaluated. Convolutional Neural Networks (CNN) were trained on 2346 pictures of equine eyes, which were augmented to 9384 images. 261 separate unmodified images were used to evaluate the performance of the trained network.

RESULTS

Cross validation showed accuracy of 99.82% on training data and 96.66% on validation data when distinguishing between three categories (uveitis, other ophthalmic diseases, healthy).

MAIN LIMITATIONS

One source of selection bias for the artificial intelligence presumably was the increased pupil size, which was mainly present in horses with ophthalmic diseases due to the use of mydriatics, and was not homogeneously dispersed in all categories of the dataset.

CONCLUSIONS

Our system for detection of equine uveitis is unique and novel and can differentiate between uveitis and other equine ophthalmic diseases. Its development also serves as a proof-of-concept for image-based detection of ophthalmic diseases in general and as a basis for its further use and expansion.

Health Demands Moderate the Link Between Willpower Beliefs and Physical Activity in Patients with Knee Osteoarthritis

BACKGROUND

Regular physical activity (PA) was found to alleviate pain and improve functioning among patients with osteoarthritis of the knee (OAK). Heightened health demands due to OAK severity, body mass index (BMI), and depressive symptoms may require self-regulatory strategies to engage in more PA. Research on willpower-the capacity to exert self-control-suggests that believing that willpower is a nonlimited rather than a limited resource predicts effective self-regulation specifically when demands are high. The present study examines the association of OAK patients' willpower beliefs with their daily PA as a function of health demands.

METHODS

To identify the moderating role of OAK severity (WOMAC), BMI, and depressive symptoms (CES-D) on the link between willpower beliefs and objectively assessed PA over a 7-day period, baseline data of a registered randomized controlled trial with 243 patients (Mage = 65.47 years, SD = 0.49) were examined in secondary analyses.

RESULTS

Moderation analyses revealed that overall positive associations of willpower beliefs with PA were further qualified by OAK severity, BMI, and depressive symptoms. When patients faced less health demands, believing that willpower is nonlimited was associated with more PA. When health demands were higher, willpower beliefs were not associated with PA.

CONCLUSION

OAK patients' willpower beliefs were associated with PA. However, facing more health demands seemed to erase this beneficial link. Improving willpower beliefs by way of intervention may help to shed more light on predictive direction and ways to overcome barriers to regular physical activity.

Pacinian neuromas and neurofibromas of the hands and fingers: a systematic review

Tumours involving Pacinian corpuscles are rare. The literature identifies two main pathological disorders: the Pacinian corpuscle neuroma or hyperplasia and the Pacinian corpuscle neurofibroma. Published data are confusing and at times conflicting. This systematic review summarizes the available data in order to support clinicians in the differential diagnosis with other tumours responsible for unclear symptoms in the hands and fingers. We identified 67 pertinent articles. Although some similarities have been described, the two tumours have relevant differences, specifically when comparing age of the patient, location, symptoms, characteristic of a mass, and aetiology. All these factors should be taken into account in order to improve diagnostic accuracy. Despite the low incidence of unsuccessful surgeries, extraordinary measures are occasionally necessary to achieve complete resolution of symptoms.

SLCV-a supervised learning-computer vision combined strategy for automated muscle fibre detection in cross-sectional images

Muscle fibre cross-sectional area (CSA) is an important biomedical measure used to determine the structural composition of skeletal muscle, and it is relevant for tackling research questions in many different fields of research. To date, time consuming and tedious manual delineation of muscle fibres is often used to determine the CSA. Few methods are able to automatically detect muscle fibres in muscle fibre cross-sections to quantify CSA due to challenges posed by variation of brightness and noise in the staining images. In this paper, we introduce the supervised learning-computer vision combined pipeline (SLCV), a robust semi-automatic pipeline for muscle fibre detection, which combines supervised learning (SL) with computer vision (CV). SLCV is adaptable to different staining methods and is quickly and intuitively tunable by the user. We are the first to perform an error analysis with respect to cell count and area, based on which we compare SLCV to the best purely CV-based pipeline in order to identify the contribution of SL and CV steps to muscle fibre detection. Our results obtained on 27 fluorescence-stained cross-sectional images of varying staining quality suggest that combining SL and CV performs significantly better than both SL-based and CV-based methods with regards to both the cell separation- and the area reconstruction error. Furthermore, applying SLCV to our test set images yielded fibre detection results of very high quality, with average sensitivity values of 0.93 or higher on different cluster sizes and an average Dice similarity coefficient of 0.9778.

Facilitating physical activity and reducing symptoms in patients with knee osteoarthritis: study protocol of a randomized controlled trial to test a theory-based PrevOP-psychological adherence program (PrevOP-PAP)

Background

The present randomized controlled trial, which is crossed with the “PREVenting the impairment of primary Osteoarthritis by high impact long-term Physical exercise regimen” Main Medical Trial (PrevOP-MMT), aims to evaluate a psychological adherence program (PrevOP-PAP), and is designed to support persons with knee osteoarthritis (OAK) in the uptake and maintenance of regular physical activity to reduce OAK symptoms. The PrevOP-PAP is based on the Health Action Process Approach (HAPA), a social-cognitive theory predicting health behavior change in individuals, extended here by social network characteristics and social exchange processes. It is expected that participants with OAK receiving the PrevOP-PAP will maintain higher levels of regular physical activity throughout a 24-month period and consequently report lower levels of OAK symptoms than participants of an active control condition.

Methods

A total of N = 240 participants with medically verified moderate OAK will be randomly assigned to an intervention condition (PrevOP-PAP-I; 50%) or an active control condition (PrevOP-PAP-CTRL). The PrevOP-PAP-I includes a motivational intervention, repeated self-regulation interventions, and a network creation intervention delivered over 12 months. Modes of intervention delivery include a paper-pencil motivation leaflet with a quiz, a computer-assisted face-to-face intervention, four computer assisted phone-based interventions, and activity calendars. The PrevOP-PAP-CTRL includes the motivational intervention only. Primary outcome will be OAK symptoms. Secondary outcomes include objectively and subjectively measured physical activity and indicators of quality of life. Other outcomes are HAPA-derived self-regulatory indicators as well as proposed social network and social exchange mechanisms of health behavior change. Assessments take place at baseline, 6 months, 12 months, 18 months, and 24 months following baseline.

Discussion

Based on the extended HAPA, this study seeks to reveal the self-regulatory and social mechanisms of the uptake and maintenance of physical activity and their relation to disease symptoms in persons with OAK. The design and evaluation of this program are intended to become a yardstick for future development and implementation of digitalized psychological adherence programs in this population.

Trial registration

German Clinical Trials Register; also available at http://apps.who.int/trialsearch/; registration number: DRKS00009677; date of registration: 26 January 2016.

Delayed recognition of an ipsilateral femoral neck and shaft fracture leading to preventable subsequent complications: a case report

BACKGROUND

Ipsilateral femoral shaft and neck fractures are rare injuries, affecting mostly young patients who sustained high-energy traumas. In 19-50% of cases, the femoral fracture is misdiagnosed or overlooked at the initial presentation, with reportedly increased risk of complications such as non-union and avascular necrosis. We present a case of an ipsilateral femoral neck and shaft fracture, which was missed at initial presentation despite radiographic and computed tomography (CT) scan evaluation.

CASE PRESENTATION

A 56-year old female was admitted to our institution following a high-energy trauma (fall from 6 m). Initial radiographic and CT scan evaluation revealed a displaced femoral shaft fracture but no other femoral fractures were detected. Closed reduction and external fixation of the femoral shaft fracture was performed in the emergency setting. Follow-up radiologic evaluations revealed an ipsilateral laterally displaced femoral neck fracture. Despite cephalomedullary nail fixation of both fractures performed on the third day from the initial injury, the patient developed a non-union of the femoral neck fracture, which led to cut-out of the lag screw with associated varus failure of the femoral neck fracture requiring surgical revision and implant of a bipolar hemiarthroplasty at one year follow up. The postoperative course was uneventful and the patient had a full long-term recovery.

CONCLUSION

This case report exemplifies the need to maintain the highest level of suspiciousness for the concomitant presence of an ipsilateral femoral neck fracture when treating polytraumatized patients who sustained a femoral shaft fracture as a consequence of a high-energy trauma. Furthermore, the pre-operative standardized radiological evaluation (plain x-ray and CT scan) might not always help in ruling out these fractures. It is therefore necessary to adopt additional standardized radiographic protocols not only in the pre-operative but also in the intra-operative and immediate post-operative settings.

Radiologic diagnostic procedures in severely injured patients - is only whole-body multislice computed tomography the answer?

BACKGROUND

Whole-body multislice computed tomography (WB-MSCT) has become an important diagnostic tool in the early treatment phase of severely injured patients. The optimal moment of WB-MSCT's use during this treatment phase remains unclear. Many trauma centers use WB-MSCT in addition to conventional radiographs, while some trauma centers use WB-MSCT as the only radiological tool. The aim of this study was to determine the differences between these two protocols and to answer the question of whether conventional radiographs can still be used in the safe treatment of polytrauma patients.

METHODS

Patients from the TraumaRegister DGU® with an injury severity score (ISS) of ≥16 were included. Group I received conventional radiographs and focused assessment with sonography in trauma (FAST) prior to a WB-MSCT, and group II received an initial WB-MSCT and FAST. Both groups were compared concerning treatment time and outcome.

RESULTS

A total of 3,995 patients in group I were compared to 4,025 patients in group II. There were no differences in ISS (29.97 vs. 29.94), gender (male: 73.5% vs. 72.8%), age (45.47 vs. 45.12 years), or calculated mortality (21.41% vs. 21.44%). Time needed in the resuscitation room was slightly longer in group I (72 vs. 64 min); the durations until admittance to the ICU and arrival to the OR were not significantly different between the groups. There was no difference in mortality (18.2% vs. 18.4%) or the standardized mortality ratio (SMR) (0.85 vs. 0.86).

CONCLUSIONS

WB-MSCT plays an inherent role in the treatment of multiple-injured patients. However, the use of WB-MSCT as the only diagnostic method in the resuscitation room is not needed. Conventional radiographs and FAST followed by WB-MSCT can be performed in the early resuscitation phase without impairing patient outcomes. This approach enables the emergency room team to perform life-saving procedures - chest-tube insertion, laparotomy, cardiopulmonary resuscitation -immediately and simultaneous. Nevertheless, randomized multi-center trials are needed to determine the comparability and effectiveness of these algorithms.

In vitro characterization of self-assembled anterior cruciate ligament cell spheroids for ligament tissue engineering

Tissue engineering of an anterior cruciate ligament (ACL) implant with functional enthesis requires site-directed seeding of different cell types on the same scaffold. Therefore, we studied the suitability of self-assembled three-dimensional spheroids generated by lapine ACL ligament fibroblasts for directed scaffold colonization. The spheroids were characterized in vitro during 14 days in static and 7 days in dynamic culture. Size maintenance of self-assembled spheroids, the vitality, the morphology and the expression pattern of the cells were monitored. Additionally, we analyzed the total sulfated glycosaminoglycan, collagen contents and the expression of the ligament components type I collagen, decorin and tenascin C on protein and for COL1A1, DCN and TNMD on gene level in the spheroids. Subsequently, the cell colonization of polylactide-co-caprolactone [P(LA-CL)] and polydioxanone (PDS) polymer scaffolds was assessed in response to a directed, spheroid-based seeding technique. ACL cells were able to self-assemble spheroids and survive over 14 days. The spheroids decreased in size but not in cellularity depending on the culture time and maintained or even increased their differentiation state. The area of P[LA-CL] scaffolds, colonized after 14 days by the cells of one spheroid, was in average 4.57 ± 2.3 mm(2). Scaffolds consisting of the polymer P[LA-CL] were more suitable for colonization by spheroids than PDS embroideries. We conclude that ACL cell spheroids are suitable as site-directed seeding strategy for scaffolds in ACL tissue engineering approaches and recommend the use of freshly assembled spheroids for scaffold colonization, due to their balanced proliferation and differentiation.

The influence of IL-10 and TNFα on chondrogenesis of human mesenchymal stromal cells in three-dimensional cultures

Chondrogenic differentiated mesenchymal stromal cells (MSCs) are a promising cell source for articular cartilage repair. This study was undertaken to determine the effectiveness of two three-dimensional (3D) culture systems for chondrogenic MSC differentiation in comparison to primary chondrocytes and to assess the effect of Interleukin (IL)-10 and Tumor Necrosis Factor (TNF)α on chondrogenesis by MSCs in 3D high-density (H-D) culture. MSCs were isolated from femur spongiosa, characterized using a set of typical markers and introduced in scaffold-free H-D cultures or non-woven polyglycolic acid (PGA) scaffolds for chondrogenic differentiation. H-D cultures were stimulated with recombinant IL-10, TNFα, TNFα + IL-10 or remained untreated. Gene and protein expression of type II collagen, aggrecan, sox9 and TNFα were examined. MSCs expressed typical cell surface markers and revealed multipotency. Chondrogenic differentiated cells expressed cartilage-specific markers in both culture systems but to a lower extent when compared with articular chondrocytes. Chondrogenesis was more pronounced in PGA compared with H-D culture. IL-10 and/or TNFα did not impair the chondrogenic differentiation of MSCs. Moreover, in most of the investigated samples, despite not reaching significance level, IL-10 had a stimulatory effect on the type II collagen, aggrecan and TNFα expression when compared with the respective controls.

Traumatic Dissection of Four Brain-Supplying Arteries without Neurologic Deficit

Study Design Case report and review of the literature. Objectives Case report of a traumatic dissection of all major brain-supplying arteries resulting from a horseback-riding accident. Overview of the literature on diagnostic and therapeutic recommendations. Methods Case presentation. For the discussion, handpicked articles and PubMed database research with the keywords "dissection," "vertebral artery," "spine trauma," "computed tomography," "magnetic resonance imaging," and "angiography" were used. Results Despite high-energy induced acute lesion of all four cervical arteries, this 45-year-old patient did not demonstrate signs of microemboli nor suffer from stroke. Conclusion In case of high-energy trauma of the head and/or the neck, emergency physicians must consider traumatic cervical artery dissection (TCAD). Thus, emergency care algorithms should routinely include computed tomography angiography and magnetic resonance imaging. Although the incidence of TCAD-induced stroke is low, antiplatelet therapy is recommended in the presence of TCAD.

Regulation of osteoarthritis-associated key mediators by TNFα and IL-10: effects of IL-10 overexpression in human synovial fibroblasts and a synovial cell line

Synovial fibroblasts (SF) contribute to the pathogenesis of osteoarthritis (OA), but the effects of intra-articular cytokines on SF are not completely understood. The aim of this study was to characterize the interplay between tumor necrosis factor (TNF)α and the anti-inflammatory interleukin (IL)-10. Non-immortalized human SF and SF of the human cell line K4IM were stimulated with recombinant TNFα, IL-10, or TNFα + IL-10 (10 ng/ml each) for 24 h or transduced with an adenoviral vector overexpressing human IL-10 (hIL-10) and subsequently treated with 10 ng/ml TNFα for 24 h. Effects on the gene expression and protein synthesis of IL-6, IL-10, matrix metalloproteinases (MMP)-1, -3, type I collagen, β1-integrin, and CD44 were investigated via real-time detection polymerase chain reaction, immunofluorescence labeling, flow cytometry, and Western blotting. IL-10 release by transduced SF was confirmed with enzyme-linked immunosorbent assay. Both cell populations were activated by TNFα and by TNFα + IL-10, increasing their gene expression and protein synthesis of IL-6, IL-10, MMP-1, and MMP-3 and altering the synthesis of type I collagen, β1-integrin, and CD44. hIL-10 overexpression greatly elevated the gene expression and protein synthesis of IL-10. However, transduction did not significantly affect the gene expression of IL-6, MMP-1, and MMP-3 in SF. The increased expression of pro-inflammatory and catabolic mediators in TNFα-activated SF indicates their role in OA pathogenesis, suggesting they are a potential therapeutic target. Although the vigorousness of the responses of non-immortalized SF and K4IM clearly differ, the K4IM cell line seems to be a suitable model for non-immortalized human SF.

Osteochondral articular defect repair using auricle-derived autologous chondrocytes in a rabbit model

Hypothesizing that the implantation of non-articular (heterotopic) chondrocytes might be an alternative approach to support articular cartilage repair, we analyzed joint cartilage defect healing in the rabbit model after implantation of autologous auricle-derived (auricular) chondrocytes. Autologous lapine articular and auricular chondrocytes were cultured for 3 weeks in polyglycolic acid (PGA) scaffolds before being implanted into critical sized osteochondral defects of the rabbit knee femoropatellar groove. Cell-free PGA scaffolds and empty defects served as controls. Construct quality was determined before implantation and defect healing was monitored after 6 and 12 weeks using vitality assays, macroscopical and histological score systems. Neo-cartilage was formed in the PGA constructs seeded with both articular and auricular chondrocytes in vitro and in vivo. At the histological level, cartilage repair was slightly improved when using autologous articular chondrocyte seeded constructs compared to empty defects and was significantly superior compared to defects treated with auricular chondrocytes 6 weeks after implantation. Although only the immunohistological differences were significant, auricular chondrocyte implantation induced an inferior healing response compared with the empty defects. Elastic auricular chondrocytes might maintain some tissue-specific characteristics when implanted into joint cartilage defects which limit its repair capacity.

The SCIentinel study--prospective multicenter study to define the spinal cord injury-induced immune depression syndrome (SCI-IDS)--study protocol and interim feasibility data

Background

Infections are the leading cause of death in the acute phase following spinal cord injury and qualify as independent risk factor for poor neurological outcome (“disease modifying factor”). The enhanced susceptibility for infections is not stringently explained by the increased risk of aspiration in tetraplegic patients, neurogenic bladder dysfunction, or by high-dose methylprednisolone treatment. Experimental and clinical pilot data suggest that spinal cord injury disrupts the balanced interplay between the central nervous system and the immune system. The primary hypothesis is that the Spinal Cord Injury-induced Immune Depression Syndrome (SCI-IDS) is 'neurogenic’ including deactivation of adaptive and innate immunity with decreased HLA-DR expression on monocytes as a key surrogate parameter. Secondary hypotheses are that the Immune Depression Syndrome is i) injury level- and ii) severity-dependent, iii) triggers transient lymphopenia, and iv) causes qualitative functional leukocyte deficits, which may endure the post-acute phase after spinal cord injury.

Methods/Design

SCIentinel is a prospective, international, multicenter study aiming to recruit about 118 patients with acute spinal cord injury or control patients with acute vertebral fracture without neurological deficits scheduled for spinal surgery. The assessment points are: i) <31 hours, ii) 31–55 hours, iii) 7 days, iv) 14 days, and v) 10 weeks post-trauma. Assessment includes infections, concomitant injury, medication and neurological classification using American Spinal Injury Association impairment scale (AIS) and neurological level. Laboratory analyses comprise haematological profiling, immunophenotyping, including HLA-DR expression on monocytes, cytokines and gene expression of immune modulators. We provide an administrative interim analysis of the recruitment schedule of the trial.

Discussion

The objectives are to characterize the dysfunction of the innate and adaptive immune system after spinal cord injury and to explore its proposed 'neurogenic’ origin by analyzing its correlation with lesion height and severity. The trial protocol considers difficulties of enrolment in an acute setting, and loss to follow up. The administrative interim analysis confirmed the feasibility of the protocol. Better understanding of the SCI-IDS is crucial to reduce co-morbidities and thereby to attenuate the impact of disease modifying factors to protect neurological “outcome at risk”. This putatively results in improved spinal cord injury medical care.

Trial registration

DRKS-ID: DRKS00000122 (German Clinical Trials Registry)

Hybrid pig versus Göttingen minipig-derived cartilage and chondrocytes show pig line-dependent differences

Minipigs are widely used as a large animal model for cartilage repair. However, many in vitro studies are based on porcine chondrocytes derived from abundantly available premature hybrid pigs. It remains unclear whether pig line-dependent differences exist which could limit the comparability between in vitro and in vivo results using either hybrid or miniature pig articular chondrocytes. Porcine knee joint femoral cartilage was isolated from 3- to 5-month-old hybrid pigs and Göttingen minipigs. Cartilage from both pig lines was analysed for thickness, zonality, cell content, size and proteoglycan deposition. Cultured articular chondrocytes from both pig lines were investigated for gene and/or protein expression of cartilage-specific proteins such as type II collagen, aggrecan, the chondrogenic transcription factor Sox9, non-specific type I collagen and the cell-matrix receptor β1-integrin. Cartilage was significantly thinner in the miniature pig compared to the hybrid pig, but the differences between the medial and lateral femur condyles did not reach a significant level. Knee joint cartilage zone formation started only in the minipig, whereas cellularity and cell diameters were comparable in both pig lines. Blood vessels could be detected in the hybrid pig but not the minipig cartilage. Sulphated proteoglycan deposition was more pronounced in cartilage zones II–IV of both pig lines. Minipig chondrocytes expressed type II and I collagen, Sox9 and β1-integrin at a higher level than hybrid pig chondrocytes. These distinct line-dependent differences should be considered when using hybrid pig-derived chondrocytes for tissue engineering and Göttingen minipigs as a large animal model.

Human hamstring tenocytes survive when seeded into a decellularized porcine Achilles tendon extracellular matrix

Tendon ruptures and defects remain major orthopaedic challenges. Tendon healing is a time-consuming process, which results in scar tissue with an altered biomechanical competence. Using a xenogeneic tendon extracellular matrix (ECM) as a natural scaffold, which can be reseeded with autologous human tenocytes, might be a promising approach to reconstruct damaged tendons. For this purpose, the porcine Achilles (AS) tendons serving as a scaffold were histologically characterized in comparison to human cell donor tendons. AS tendons were decellularized and then reseeded with primary human hamstring tenocytes using cell centrifuging, rotating culture and cell injection techniques. Vitality testing, histology and glycosaminoglycan/DNA quantifications were performed to document the success of tendon reseeding. Porcine AS tendons were characterized by a higher cell and sulfated glycosaminoglycan content than human cell donor tendons. Complete decellularization could be achieved, but led to a wash out of sulfated glycosaminoglycans. Nevertheless, porcine tendon could be recellularized with vital human tenocytes. The recellularization led to a slight increase in cell number compared to the native tendon and some glycosaminoglycan recovery. This study indicates that porcine tendon can be de- and recellularized using adult human tenocytes. Future work should optimize cell distribution within the recellularized tendon ECM and consider tendon- and donor species-dependent differences.

[Dislocation of the atlantoaxial joint]

Injuries of the cervical spine in adolescents only occur in 0.2 % of cases. Due to the mismatch of size of the head in comparison to the relatively weakly developed neck muscles at this age, the cranial section is more vulnerable to injuries of any kind compared to the lower sections of the cervical spine. In children isolated ligament trauma is more common than fractures due to the relatively good bone structure combined with a lower bone density but the risk for fractures increases with the age of the patient. Atlantoaxial dislocation (AAD) in children is a very rare mostly ligamentous injury. A differentiation is made between traumatic AAD and the much more common non-traumatic AAD described in the literature. Although the cause is still unknown different risk factors have been isolated that seem to increase the risk for non-traumatic AAD. The following article presents guidelines for the diagnosis and treatment of this rare type of injury and also describes the case of a 19-year-old female who presented at the emergency department with an AAD without a history of trauma. After successful closed repositioning the neck was stabilized in a semi-rigid cervical collar for 6 weeks.

Influence of fiber orientation in electrospun polymer scaffolds on viability, adhesion and differentiation of articular chondrocytes

Degradable polymers with a tailorable degradation rate might be promising candidate materials for biomaterial-based cartilage repair. In view of the poor intrinsic healing capability of cartilage, implantation of autologous chondrocytes seeded on a biocompatible slow degrading polymer might be an encouraging approach to improve cartilage repair in the future. This study was undertaken to test if the fiber orientation (random versus aligned) of two different degradable polymers and a polymer intended for long term applications could influence primary articular chondrocytes growth and ultrastructure. A degradable copoly(ether)esterurethane (PDC) was synthesized via co-condensation of poly(p-dioxanone)diol and poly(ε-caprolactone)diol using an aliphatic diisocyanate as linker. Poly(p-dioxanone) (PPDO) was applied as commercially available degradable polymer, while polyetherimide (PEI) was chosen as biomaterial enabling surface functionalization. The fibrous scaffolds of PDC and PPDO were obtained by electrospinning using 1,1,1,3,3,3 hexafluoro-2-propanol (HFP), while for PEI dimethyl acetamide (DMAc) was applied as solvent. Primary porcine articular chondrocytes were seeded at different cell densities on the fibrous polymer scaffolds and analyzed for viability (fluorescein diacetate/ethidiumbromide staining), for type II collagen synthesis (immunolabelling), ultrastructure and orientation on the fibers (SEM: scanning electron microscopy). Vital chondrocytes adhered on all electrospun scaffolds irrespective of random and aligned topologies. In addition, the chondrocytes produced the cartilage-specific type II collagen on all tested polymer topologies suggesting their differentiated functions. SEM revealed an almost flattened chondrocytes shape on scaffolds with random fiber orientation: whereby chondrocytes growth remained mainly restricted to the scaffold surface. On aligned fibers the chondrocytes exhibited a more spindle-shaped morphology with rougher cell surfaces but only a minority of the cells aligned according to the fibers. As a next step the reduction of the fiber diameter of electrospun scaffolds should be addressed as an important parameter to mimic cartilage ECM structure.

Fracture of the shoulder girdle in multiply injured patients - an imperative for a high level of suspicion for associated neurovascular injuries

Background

The combination of a bony injury to the shoulder girdle and damage to the brachial plexus and the subclavian vessels is a rare finding. The cases of this combined injury pattern described in the literature are most notably reported in multiply-injured patients after high velocity trauma.

Findings

Three cases were admitted to our hospital after motorcycle accidents resulting in a combination of severe bony injuries to the shoulder girdle, to the subclavian artery and a lesion to the brachial plexus. Based on these three clinical cases the patterns of injury, as well as primary and secondary treatment approaches are presented.

Conclusion

The early detection of these injuries can be difficult in given acute, life threatening injuries addressed first in these multiply injured patients. A high level of suspicion, in conjunction with standardized ATLS based institutional protocols for secondary and tertiary survey, should increase the likelihood of a timely detection and early management of these rare but potentially devastating injuries.

Heterotopic and orthotopic autologous chondrocyte implantation using a minipig chondral defect model

Implantation of non-articular (heterotopic) chondrocyte-based implants might be an alternative approach to articular cartilage repair. This strategy could be helpful in cases in which there are no or too few articular chondrocytes available. Therefore, this study was undertaken to compare joint cartilage defect healing in the minipig model after implantation of heterotopic auricular and orthotopic articular chondrocytes. Poly-glycolic acid (PGA) associated three-dimensional (3D) constructs were prepared culturing autologous minipig-derived articular and auricular chondrocytes for 7 days in a dynamic culture system. Chondrocyte PGA constructs were implanted into 8mm diameter and ∼1.1mm deep chondral defects within the medial and lateral condyles of the minipig knee joints. Empty defects served as controls for assessment of the intrinsic healing response. Defect healing was monitored 6 months post implantation using a macroscopic and microscopic score system and biomechanical analysis. Neo-cartilage formation could be observed in the PGA constructs seeded with articular and auricular chondrocytes in vivo. The defect healing did not significantly differ at the macroscopic and histological level in response to implantation of either autologous articular or auricular chondrocytes seeded constructs compared with the empty defects. Although the differences were not significant, the auricular chondrocytes-based implants led to a slightly inferior repair quality at the macroscopic level, but a histologically superior healing response when compared with the empty defect group. However, biomechanical analysis revealed a higher stiffness in repair tissues produced by auricular chondrocyte implantation compared with the other groups. Deduced from these results, articular chondrocytes represent the preferable cell source for implantation.

High-energy proximal femur fractures in geriatric patients: a retrospective analysis of short-term complications and in-hospital mortality in 32 consecutive patients

BACKGROUND

There is limited information in the literature on the outcomes and complications in elderly patients who sustain high-energy hip fractures. As the population ages, the incidence of high-energy geriatric hip fractures is expected to increase. The purpose of this study was to analyze the outcomes and complications in patients aged 65 years or older, who sustained a high-energy proximal femur fracture.

METHODS

Retrospective review of a prospective trauma database from January 2000 to April 2011 at a single US academic level-1 trauma center. Inclusion criteria consisted of all patients of age 65 years or older, who sustained a proximal femur fracture related to a high-energy trauma mechanism. Details concerning injury, acute treatment, and clinical course and outcome were obtained from medical records and radiographs.

RESULTS

We identified 509 proximal femur fractures in patients older than 65 years of age, of which 32 (6.3%) were related to a high-energy trauma mechanism. The mean age in the study group was 72.2 years (range 65-87), with a mean injury severity score of 20 points (range 9-57). Three patients died before discharge (9.4%), and 22 of 32 patients sustained at least one complication (68.8%). Blunt chest trauma represented the most frequently associated injury, and the main root cause of pulmonary complications. The patients' age and comorbidities did not significantly correlate with the rate of complications and the 1-year mortality.

CONCLUSIONS

High-energy proximal femur fractures in elderly patients are not very common and are associated with a low in-hospital mortality rate of less than 10%, despite high rate of complications of nearly 70%. This selective cohort of patients requires a particular attention to respiratory management due to the high incidence of associated chest trauma.

Decellularized tendon extracellular matrix-a valuable approach for tendon reconstruction?

Tendon healing is generally a time-consuming process and often leads to a functionally altered reparative tissue. Using degradable scaffolds for tendon reconstruction still remains a compromise in view of the required high mechanical strength of tendons. Regenerative approaches based on natural decellularized allo- or xenogenic tendon extracellular matrix (ECM) have recently started to attract interest. This ECM combines the advantages of its intrinsic mechanical competence with that of providing tenogenic stimuli for immigrating cells mediated, for example, by the growth factors and other mediators entrapped within the natural ECM. A major restriction for their therapeutic application is the mainly cell-associated immunogenicity of xenogenic or allogenic tissues and, in the case of allogenic tissues, also the risk of disease transmission. A survey of approaches for tendon reconstruction using cell-free tendon ECM is presented here, whereby the problems associated with the decellularization procedures, the success of various recellularization strategies, and the applicable cell types will be thoroughly discussed. Encouraging in vivo results using cell-free ECM, as, for instance, in rabbit models, have already been reported. However, in comparison to native tendon, cells remain mostly inhomogeneously distributed in the reseeded ECM and do not align. Hence, future work should focus on the optimization of tendon ECM decellularization and recolonization strategies to restore tendon functionality.

Anaphylatoxin receptors and complement regulatory proteins in human articular and non-articular chondrocytes: interrelation with cytokines

Tissue trauma induces an inflammatory response associated with a cytokine release that may engage complement pathways. Cytokine-mediated complement expression may contribute to cartilage degradation. Hence, we analysed the complement expression profile in primary articular and non-articular chondrocytes and its interrelation with cytokines. The expression of the anaphylatoxin receptors (C3aR and C5aR) and the complement regulatory proteins (CPRs) CD35, CD46, CD55 and CD59 was studied in cultured articular, auricular and nasoseptal chondrocytes using RTD-PCR and immunofluorescence labelling. The complement profile of peripheral blood mononuclear cells (PBMCs) was opposed to the expression in articular chondrocytes. The time-dependent regulation (6 and 24 h) of these complement factors was assessed in articular chondrocytes in response to the cytokines TNFα, IL-10 or TNFα combined with IL-10 (each 10 ng/mL). C3aR, C5aR, CD46, CD55 and CD59 but almost no CD35 mRNA was expressed in any of chondrocyte types studied. The anaphylatoxin receptor expression was lower and that of the CRPs was higher in chondrocytes when compared with PBMCs. The majority of the studied complement factors were expressed at a significantly lower level in non-articular chondrocytes compared with the articular chondrocytes. TNFα significantly increased the C3aR expression in chondrocytes after 6 and 24 h. TNFα + IL-10 significantly downregulated C5aR and IL-10 significantly inhibited the CD46 and CD55 gene expression after 24 h. C5aR and CD55 could be localised in cartilage in situ. Anaphylatoxin receptors and CRPs are regulated differentially by TNFα and IL-10. Whether cytokine-induced complement activation occurs in response to cartilage trauma has to be further identified.

Tenocytes, pro-inflammatory cytokines and leukocytes: a relationship?

Leukocyte derived pro-inflammatory mediators could be involved in tendon healing and scar formation. Hence, the effect of autologous leukocytes (PBMCs, peripheral blood mononuclear cells and neutrophils) on primary rabbit Achilles tenocytes gene expression was tested in insert assisted co-cultures. Subsequently, tenocytes gene expression of extra-cellular matrix (ECM) components (type I collagen, decorin, fibronectin), the cell-ECM receptor β1-integrin, the angiogenic factor myodulin, ECM degrading matrix-metalloproteinase (MMP)1 and pro-inflammatory cytokines (interleukin [IL]-1β, tumour necrosis factor [TNFα] and IL-6) was analysed. The only significant effect of leukocytes on tenocytes ECM genes expression was a suppression of type I collagen by neutrophils combined with TNFα stimulation. The same effect could be observed analysing the β1-integrin and myodulin gene expression. However, PBMCs up-regulated significantly cytokine and MMP1 gene expression in tenocytes. These in vitro results suggest that mononuclear cells could present an exogenic stimulus for the induction of pro-inflammatory and catabolic mediators in tendon.

The role of pro-inflammatory and immunoregulatory cytokines in tendon healing and rupture: new insights

Owing to limited self-healing capacity, tendon ruptures and healing remain major orthopedic challenges. Increasing evidence suggests that post-traumatic inflammatory responses, and hence, cytokines are involved in both cases, and also in tendon exercise and homeostasis. This review summarizes interrelations known between the cytokines interleukin (IL)-1β, tumor necrosis factor (TNF)α, IL-6 and vascular endothelial growth factor (VEGF) in tendon to assess their role in tendon damage and healing. Exogenic cytokine sources are blood-derived leukocytes that immigrate in damaged tendon. Endogenous expression of IL-1β, TNFα, IL-6, IL-10 and VEGF was demonstrated in tendon-derived cells. As tendon is a highly mechanosensitive tissue, cytokine homeostasis and cell survival underlie an intimate balance between adequate biomechanical stimuli and disturbance through load deprivation and overload. Multiple interrelations between cytokines and tendon extracellular matrix (ECM) synthesis, catabolic mediators e.g. matrix-degrading enzymes, inflammatory and angiogenic factors (COX-2, PGE2, VEGF, NO) and cytoskeleton assembly are evident. Pro-inflammatory cytokines affect ECM homeostasis, accelerate remodeling, amplify biomechanical adaptiveness and promote tenocyte apoptosis. This multifaceted interplay might both contribute to and interfere with healing. Much work must be undertaken to understand the particular interrelation of these inflammatory and regulatory mediators in ruptured tendon and healing, which has relevance for the development of novel immunoregulatory therapeutic strategies.

Clinical diagnosis versus autopsy findings in polytrauma fatalities

Objectives

The aim of the study was to determine if differences in clinical diagnosis versus autopsy findings concerning the cause of death in polytrauma fatalities would be detected in 19 cases of fatal polytrauma from a Level 1 trauma centre.

Methods

Clinical diagnoses determining the cause of death in 19 cases of fatal polytrauma (2007 - 2008) from a Level 1 trauma centre were correlated with autopsy findings.

Results

In 13 cases (68%), the clinical cause of death and the cause of death as determined by autopsy were congruent. Marginal differences occurred in three (16%) patients while obvious differences in interpreting the cause of death were found in another three (16%) cases. Five fatalities (three with obvious differences and two with marginal differences) were remarked as early death (1-4 h after trauma) and one fatality with marginal differences as late death (>1 week after trauma). Obvious and marginal discrepancies mostly occurred in the early phase of treatment, especially when severely injured patients were admitted to the emergency room undergoing continued cardiopulmonary resuscitation, i. e. limiting diagnostic procedures, and thus the clinical cause of death was essentially determined by basic emergency diagnostics.

Conclusions

Autopsy as golden standard to define the cause of death in fatal polytrauma varies from the clinical point of view, depending on the patient's pre-existing condition, mechanism of polytrauma, necessity of traumatic cardiopulmonary resuscitation, survival time, and thus the possibility to perform emergency diagnostics. An autopsy should be performed at least in cases of early fatal polytrauma to help establishing the definite cause of death. Moreover, autopsy data should be included in trauma registries as a quality assessment tool.

Extracellular matrix expression of human tenocytes in three-dimensional air-liquid and PLGA cultures compared with tendon tissue: implications for tendon tissue engineering

Tenocyte transplantation may prove to be an approach to support healing of tendon defects. Cell-cell and cell-matrix contacts within three-dimensional (3D) cultures may prevent tenocyte dedifferentiation observed in monolayer (2D) culture. The present study compares both neotissue formation and tenocyte extracellular matrix (ECM) expression in 2D and 3D cultures directly with that of native tendon, in order to determine optimal conditions for tendon tissue engineering. Primary human tenocytes were embedded in poly[lactic-co-glycolic-acid] (PLGA)-scaffolds and high-density cultures. Neotissue formation was examined by hematoxyline-eosine (H&E) and immunofluorescence staining. Gene expression of ECM proteins and vascular endothelial growth factor (VEGF) was compared at days 0 (2D), 14, and 28 in 3D cultures and tendon. Histomorphology of 3D culture showed tendon-like tissue as tenocyte cell nuclei became more elongated and ECM accumulated. Type I collagen gene expression was higher in 2D culture than in tendon and decreased in 4-week-old 3D cultures, whereas type III collagen was only elevated in high-density culture compared with tendon. Decorin and COMP were reduced in 2D and increased in 3D culture almost to ex vivo level. These results suggest that the 3D high-density or biodegradable scaffolds cultures encourage the differentiation of expanded monolayer tenocytes in vitro to tendon-like tissue.

Effect of pro-inflammatory and immunoregulatory cytokines on human tenocytes

Tendon injury induces a local inflammatory response, characterized by the induction of pro-inflammatory cytokines. The aim of the present study was to analyze the effects of TNFalpha, IL-6 and IL-10 on key parameters of tendon homeostasis. Cultured primary human tenocytes were treated with the recombinant cytokines IL-6, IL-10, TNFalpha, or combinations of TNFalpha with IL-6 and IL-10 (10 ng/mL, 6, 24 h). Expression of type I collagen, elastin, MMP-1, TNFalpha, IL-1beta, IL-6, IL-10, and suppressors of cytokine signaling (SOCS1, 3) was analyzed with the use of RTD-PCR, immunocytochemistry, and Western blot analysis. In response to TNFalpha, tenocytes reduced their type I collagen deposition but increased their elastin gene expression and highly upregulated their expression for MMP-1, pro-inflammatory (TNFalpha, IL-1beta) and immunoregulatory (IL-6, IL-10) cytokines. TNFalpha stimulation augmented SOCS1, whereas SOCS3 expression in tenocytes was also induced by IL-6. The treatment of tenocytes with IL-6 and IL-10 had no effect on cytokine expression. Neither IL-6 nor IL-10 modulated the observed effects of TNFalpha significantly. These results indicate that TNFalpha strongly activates the tenocytes to amplify their own TNFalpha expression and, subsequently, that of other regulatory cytokines and matrix degrading enzymes. However, the impact of IL-6 and IL-10 on tenocytes remains unclear.

Characterization of auricular chondrocytes and auricular/articular chondrocyte co-cultures in terms of an application in articular cartilage repair

Cartilage injury remains a challenge in orthopedic surgery as articular cartilage only has a limited capacity for intrinsic healing. Autologous chondrocyte transplantation (ACT) is a suitable technique for cartilage repair, but requires articular cartilage biopsies for autologous chondrocyte expansion. The use of heterotopic chondrocytes derived from non-articular cartilage sources such as auricular chondrocytes may be a novel approach for ACT. The aim of the study is to evaluate whether co-cultured articular/auricular chondrocytes exhibit characteristics comparable to articular chondrocytes. Analysis of the proliferation rate, extracellular cartilage matrix (ECM) gene and protein expression (type II and I collagen, elastin, lubricin), beta1-integrins and the chondrogenic transcription factor sox9 in articular/auricular chondrocytes was performed using RTD-PCR, flow cytometry, immunofluorescence microscopy and Western blot analysis. Additionally, three-dimensional (3D) chondrocyte mono- and co-cultures were established. The proliferative activity and elastin gene expression were lower and that of type II collagen and lubricin was higher in articular compared with auricular chondrocytes. The species generally did not influence the chondrocyte characteristics, with the exception of type I collagen and sox9 expression, which was higher in porcine but not in human articular chondrocytes compared with both types of auricular chondrocytes. beta1-integrin gene expression did not differ significantly between the chondrocyte types. The type II collagen gene and protein expression was higher in articular chondrocyte monocultures and was slightly higher in co-cultures compared with monocultured auricular chondrocytes. Both chondrocyte types survived in co-culture. Despite their differing expression profiles, co-cultures revealed some adjustment in the ECM expression of both chondrocyte types.

Absence of the complement regulatory molecule CD59a leads to exacerbated neuropathology after traumatic brain injury in mice

Background

Complement represents a crucial mediator of neuroinflammation and neurodegeneration after traumatic brain injury. The role of the terminal complement activation pathway, leading to generation of the membrane attack complex (MAC), has not been thoroughly investigated. CD59 is the major regulator of MAC formation and represents an essential protector from homologous cell injury after complement activation in the injured brain.

Methods

Mice deleted in the Cd59a gene (CD59a^-/-) and wild-type littermates (n = 60) were subjected to focal closed head injury. Sham-operated (n = 60) and normal untreated mice (n = 14) served as negative controls. The posttraumatic neurological impairment was assessed for up to one week after trauma, using a standardized Neurological Severity Score (NSS). The extent of neuronal cell death was determined by serum levels of neuron-specific enolase (NSE) and by staining of brain tissue sections in TUNEL technique. The expression profiles of pro-apoptotic (Fas, FasL, Bax) and anti-apoptotic (Bcl-2) mediators were determined at the gene and protein level by real-time RT-PCR and Western blot, respectively.

Results

Clinically, the brain-injured CD59a^-/- mice showed a significantly impaired neurological outcome within 7 days, as determined by a higher NSS, compared to wild-type controls. The NSE serum levels, an indirect marker of neuronal cell death, were significantly elevated in CD59a^-/- mice at 4 h and 24 h after trauma, compared to wild-type littermates. At the tissue level, increased neuronal cell death and brain tissue destruction was detected by TUNEL histochemistry in CD59a^-/- mice within 24 hours to 7 days after head trauma. The analysis of brain homogenates for potential mediators and regulators of cell death other than the complement MAC (Fas, FasL, Bax, Bcl-2) revealed no difference in gene expression and protein levels between CD59a^-/- and wild-type mice.

Conclusion

These data emphasize an important role of CD59 in mediating protection from secondary neuronal cell death and further underscore the key role of the terminal complement pathway in the pathophysiology of traumatic brain injury. The exact mechanisms of complement MAC-induced secondary neuronal cell death after head injury require further investigation.

IL-10 overexpression differentially affects cartilage matrix gene expression in response to TNF-alpha in human articular chondrocytes in vitro

Cartilage-specific extracellular matrix synthesis is the prerequisite for chondrocyte survival and cartilage function, but is affected by the pro-inflammatory cytokine TNF-alpha in arthritis. The aim of the present study was to characterize whether the immunoregulatory cytokine IL-10 might modulate cartilage matrix and cytokine expression in response to TNF-alpha. Primary human articular chondrocytes were treated with either recombinant IL-10, TNF-alpha or a combination of both (at 10ng/mL each) or transduced with an adenoviral vector overexpressing human IL-10 and subsequently stimulated with 10ng/ml TNF-alpha for 6 or 24h. The effects of IL-10 on the cartilage-specific matrix proteins collagen type II, aggrecan, matrix-metalloproteinases (MMP)-3, -13 and pro-inflammatory cytokines were evaluated by real-time RT-PCR and immunohistochemistry. Transduced chondrocytes overexpressed high levels of IL-10 which significantly up-regulated collagen type II expression. TNF-alpha suppressed collagen type II and aggrecan, but increased MMP and cytokine expression in chondrocytes compared to the non-stimulated controls. The TNF-alpha mediated down-regulation of aggrecan expression was significantly antagonized by IL-10 overexpression, whereas the suppression of collagen type II was barely affected. The MMP-13 and IL-1beta expression by TNF-alpha was slightly reduced by IL-10. These results suggest that IL-10 overexpression modulates some catabolic features of TNF-alpha in chondrocytes.

Differing in vitro biology of equine, ovine, porcine and human articular chondrocytes derived from the knee joint: an immunomorphological study

For lack of sufficient human cartilage donors, chondrocytes isolated from various animal species are used for cartilage tissue engineering. The present study was undertaken to compare key features of cultured large animal and human articular chondrocytes of the knee joint. Primary chondrocytes were isolated from human, porcine, ovine and equine full thickness knee joint cartilage and investigated flow cytometrically for their proliferation rate. Synthesis of extracellular matrix proteins collagen type II, cartilage proteoglycans, collagen type I, fibronectin and cytoskeletal organization were studied in freshly isolated or passaged chondrocytes using immunohistochemistry and western blotting. Chondrocytes morphology, proliferation, extracellular matrix synthesis and cytoskeleton assembly differed substantially between these species. Proliferation was higher in animal derived compared with human chondrocytes. All chondrocytes expressed a cartilage-specific extracellular matrix. However, after monolayer expansion, cartilage proteoglycan expression was barely detectable in equine chondrocytes whereby fibronectin and collagen type I deposition increased compared with porcine and human chondrocytes. Animal-derived chondrocytes developed more F-actin fibers during culturing than human chondrocytes. With respect to proliferation and extracellular matrix synthesis, human chondrocytes shared more similarity with porcine than with ovine or equine chondrocytes. These interspecies differences in chondrocytes in vitro biology should be considered when using animal models.

Successful treatment of spondylodiscitis using titanium cages: a 3-year follow-up of 22 consecutive patients

BACKGROUND AND PURPOSE

The use of metal implants in large defects caused by spinal infection to support the anterior column is controversial, and relatively few results have been published to date. Despite the fact that there is bacterial adhesion to metal implants, the strong immunity of the highly vascularized spine because of rich muscle covering is unique. This possibly allows the use of metal implants, which have the advantage of high stability and reduced loss of correction. This is a retrospective study of patients with spondylodiscitis treated with metal implants.

PATIENTS AND METHODS

We retrospectively analyzed the outcome in 22 consecutive patients (mean age 69 (43-82) years, 15 men) with spondylodiscitis (20 lumbar and 12 thoracic discs) who had received an anterior titanium cage implantation. In 13 cases, the pathogen could be identified. Antibiotic treatment was continued for at least 12 weeks postoperatively.

RESULTS

The mean follow-up was 36 (32-47) months. Healing of inflammation was confirmed by clinical, radiographic, and laboratory parameters. The mean VAS improved from 9.1 (6-10) preoperatively to 2.6 (0-6) at the final follow-up, and the mean Oswestry disability index was 17 (0-76) at the final follow-up.

INTERPRETATION

Our findings highlight the high healing rate and stability when titanium implants are used. Prerequisites are a radical debridement, correction of deformity, and additional bony fusion by bone grafting. The increased stability, with facilitated patient mobilization, and the relatively little loss of correction using anterior and posterior implants are of considerable advantage in the treatment of the patients with multiple co-morbidities.

Apoptosis of human intervertebral discs after trauma compares to degenerated discs involving both receptor-mediated and mitochondrial-dependent pathways

Post-traumatic disc degeneration with consecutive loss of reduction and kyphosis remains a debatable issue within both the operative and nonoperative treatment regimen of thoracolumbar spine fractures. Intervertebral disc (IVD) cell apoptosis has been suggested to play a vital role in promoting the degeneration process. To evaluate and compare apoptosis-regulating signaling mechanisms, IVDs were obtained from patients with thoracolumbar spine fractures (n = 21), patients suffering from symptomatic IVD degeneration (n = 6), and from patients undergoing surgical resection of a primary vertebral tumor (n = 3 used as control samples). All tissues were prospectively analyzed in regards to caspase-3/7, -8, and -9 activity, apoptosis-receptor expression levels, and gene expression of the mitochondria-bound apoptosis-regulating proteins Bax and Bcl-2. Morphologic changes characteristic for apoptotic cell death were confirmed by H&E staining. Statistical significance was designated at p < 0.05 using the Student's t-test. Both traumatic and degenerative IVD demonstrated a significant increase of caspase-3/7 activity with evident apoptosis. Although caspase-3/7 activation was significantly greater in degenerated discs, both showed equally significant activation of the initiator caspases 8 and 9. Traumatic IVD alone demonstrated a significant increase of the Fas receptor (FasR), whereas the TNF receptor I (TNFR I) was equally up-regulated in both morbid IVD groups. Only traumatic IVD showed distinct changes in up-regulated TNF expression, in addition to significantly down-regulated antiapoptotic Bcl-2 protein. Our results suggest that post-traumatic disc changes may be promoted and amplified by both the intrinsic mitochondria-mediated and extrinsic receptor-mediated apoptosis signaling pathways, which could be, in part, one possible explanation for developing subsequent disc degeneration.

Impaired erythropoiesis after haemorrhagic shock in mice is associated with erythroid progenitor apoptosis in vivo

OBJECTIVE

Multiply traumatised patients often suffer from blood loss and from subsequent therapy-resistant anaemia, possibly mediated by apoptosis, necrosis, or humoral factors. Therefore, the underlying mechanisms were investigated in bone marrow (BM) and peripheral blood in a murine resuscitated haemorrhagic shock (HS) model.

METHODS

In healthy male mice, pressure-controlled HS was induced for 60 min. The BM was analysed for Annexin-V, 7-amino-actinomycin D, apoptotic enzymes (caspases-3/7, -8, and -9), expression of death receptors (CD120a, CD95), mitochondrial proteins (Bax, Bcl-2, Bcl-x), as well as erythropoietin (EPO) receptor (EPO-R). Blood cell count, peripheral EPO, and tumour necrosis factor-alpha response were additionally monitored.

RESULTS

Twenty-four and 72 h after HS, EPO and EPO-R were strongly up-regulated in peripheral blood and BM, respectively. Decreasing numbers of erythroid progenitors in BM after HS correlated with significant apoptotic changes confirmed by increased caspases-3/7, -8, -9 activity in total BM, death receptor CD95 and CD120a expression on erythroid progenitors, and down-regulated mitochondrial Bcl-2 expression in total BM. Erythroid progenitors in peripheral blood were found to be increased after 72 h.

CONCLUSION

Despite the massive EPO response and up-regulation of EPO-R, BM erythroblasts (EBs) decreased. This could be due to deficient maturation of erythroid progenitors. Furthermore, the increased intrinsic and extrinsic apoptosis activation suggests programmed death of erythroid progenitors. We propose that both apoptosis and negatively regulated erythropoiesis contribute to BM dysfunction, while erythroid progenitor egress plays an additional role.

Biphasic onset of splenic apoptosis following hemorrhagic shock: critical implications for Bax, Bcl-2, and Mcl-1 proteins

Introduction

The innate immune response to trauma hemorrhage involves inflammatory mediators, thus promoting cellular dysfunction as well as cell death in diverse tissues. These effects ultimately bear the risk of post-traumatic complications such as organ dysfunction, multiple organ failure, or adult respiratory distress syndrome. In this study, a murine model of resuscitated hemorrhagic shock (HS) was used to determine the apoptosis in spleen as a marker of cellular injury and reduced immune functions.

Methods

Male C57BL-6 mice were subjected to sham operation or resuscitated HS. At t = 0 hours, t = 24 hours, and t = 72 hours, mice were euthanized and the spleens were removed and evaluated for apoptotic changes via DNA fragmentation, caspase activities, and activation of both extrinsic and intrinsic apoptotic pathways. Spleens from untreated mice were used as control samples.

Results

HS was associated with distinct lymphocytopenia as early as t = 0 hours after hemorrhage without regaining baseline levels within the consecutive 72 hours when compared with sham and control groups. A rapid activation of splenic apoptosis in HS mice was observed at t = 0 hours and t = 72 hours after hemorrhage and predominantly confirmed by increased DNA fragmentation, elevated caspase-3/7, caspase-8, and caspase-9 activities, and enhanced expression of intrinsic mitochondrial proteins. Accordingly, mitochondrial pro-apoptotic Bax and anti-apoptotic Bcl-2 proteins were inversely expressed within the 72-hour observation period, thereby supporting significant pro-apoptotic changes. Solely at t = 24 hours, expression of the anti-apoptotic Mcl-1 protein shows a significant increase when compared with sham-operated and control animals. Furthermore, expression of extrinsic death receptors were only slightly increased.

Conclusion

Our data suggest that HS induces apoptotic changes in spleen through a biphasic caspase-dependent mechanism and imply a detrimental imbalance of pro- and anti-apoptotic mitochondrial proteins Bax, Bcl-2, and Mcl-1, thereby promoting post-traumatic immunosuppression.

Immunoparalysis after multiple trauma

The immunological sequelae following multiple trauma constitute an ongoing challenge in critical care management. The overall immune response to multiple trauma is a multilevel complex interdependently involving neurohormonal, cellular and haemodynamic factors. Immunoparalysis is characterised by a reduced capacity to present antigens via downregulated HLA-DR and an unbalanced monocyte-T cell interaction. Trauma-induced death of functionally conducive immune cells in the early recovery phase is significant in the emergence of posttraumatic multiple organ dysfunction or failure. Novel findings may contribute to more appropriate immunomonitoring and improved treatment. We must consider the preservation and support of immune function as the ultimate therapeutic goal, which may override the current strategy of simply antagonising excessive pro- or anti-inflammatory immune responses of the severely injured person. This review focuses on the injury-induced conduct of key immune effector cells and associated effects promoting immunoparalysis after multiple trauma.