Free-floating medial meniscus implant kinematics do not change after simulation of medial open-wedge high tibial osteotomy and notchplasty

PURPOSE

The purpose of this in-vitro study was to examine the kinematics of an artificial, free-floating medial meniscus replacement device under dynamic loading situations and different knee joint states.

METHODS

A dynamic knee simulator was used to perform dynamic loading exercises on three neutrally aligned and three 10° valgus aligned (simulating a medial openwedge high tibial osteotomy - MOWHTO) left human cadaveric knee joints. The knee joints were tested in three states (intact, conventional notchplasty, extended notchplasty) while 11 randomised exercises were simulated (jump landing, squatting, tibial rotation and axial ground impacts at 10°, 30° and 60° knee joint flexion) to investigate the knee joint and implant kinematics by means of rigidly attached reflective marker sets and an according motion analysis.

RESULTS

The maximum implant translation relative to the tibial plateau was < 13 mm and the maximum implant rotation was < 19° for all exercises. Both, the notchplasties and the valgus knee alignment did not affect the device kinematics.

CONCLUSIONS

The results of the present in-vitro study showed that the non-anchored free-floating device remains within the medial knee joint gap under challenging dynamic loading situations without indicating any luxation tendencies. This also provides initial benchtop evidence that the device offers suitable stability and kinematic behaviour to be considered a potential alternative to meniscus allograft transplantation in combination with an MOWHTO, potentially expanding the patient collective in the future.

Paper 30: Superior Improvements in Knee Pain and Function with a Novel Synthetic Medial Meniscus Replacement Prosthesis Compared to Non-surgical Care in Subjects with Knee Pain Following Partial Meniscectomy: Three-year Results from Two Prospective US Clinical Trials

Objectives:

Results from 2 FDA-regulated clinical trials demonstrate superiority of a synthetic medial meniscus prosthesis to non-surgical care in treating persistent or recurrent knee pain following previous partial meniscectomy.

Arthroscopic partial meniscectomy (APM) is the most common surgical treatment for symptomatic, irreparable meniscal tears that do not improve with non-surgical care. For many patients, APM is associated with improvements in knee pain and function, but a subset of patients report persistent or recurrent knee pain 1-2 years after APM surgery. Current treatment options for post-APM knee pain are limited, especially for patients considered too young for knee replacement. The polymeric medial meniscus prosthesis (NUsurface^â, Active Implants, Memphis TN) mimics the biomechanical function of the natural medial meniscus and provides relief from pain and improved function in subjects with knee pain following APM. The meniscus prosthesis met the primary endpoint of superiority over non-surgical care at 2 years. The current hypothesis was that investigational subjects maintained superior improvements in knee-related pain, function, and quality of life, compared to non-surgical subjects, through 3 years of follow-up.

Methods:

242 subjects (176 investigational, 66 control) treated in 2 prospective, concurrent clinical trials in the U.S., and pooled for analysis: a randomized controlled superiority trial (RCT) comparing the investigational device (investigational group) to non-surgical care (control), and a single-arm, prosthesis-only trial. Subjects had persistent knee pain and one or more previous partial meniscectomies at least 6 months before trial entry. Subject follow-up visits at 1.5 months, 6 months, 1, 2 and 3 year. Patient-reported knee pain, function, and quality of life were assessed using the Knee Injury and Osteoarthritis Outcome Score (KOOS). Treatment cessation was defined as any investigational subject who discontinued the per-protocol treatment by permanent prosthesis removal, or control subjects undergoing any surgical procedure on the index knee. Investigational subjects who underwent subsequent surgical procedures on index knees (e.g. prosthesis exchange) remained in the trial. The investigational and control cohorts analyzed were compared at each time point using a two tailed t-test. All baseline cohort comparisons of demographics were not statistically different (p>0.05).

Results:

The magnitude of improvement from baseline to 3 years was statistically superior in the investigational cohort, compared to the control cohort for all 6 KOOS subscales (Figure 1), including the primary outcomes of KOOS Overall and KOOS Pain (Figure 1A, B). Improvement in KOOS Overall and KOOS Pain for the investigational and control cohorts at 3 years were 26.4 vs 10.4 points, and 26.9 vs 15.4 points, respectively (Figure 1). These data show a statistically significant improvement, exceeding a clinically meaningful improvement of ≥20 points versus controls as early as 6 months (20.0 vs 9.2 pts), continuing through the 3-year timepoint. Controls experienced a 35% decline in KOOS Overall improvement between the 2-year and 3-year timepoint (15.9 vs 10.4). Accountability of patients not available or yet reaching the 3-year follow-up time period are reflected in Table 1. Treatment cessation through 3 years was 31% greater in the control cohort than the investigational cohort (15.0% vs. 19.6%).

Conclusions:

Three-year results demonstrate statistically superior relief from post-APM knee pain and function compared to non-surgical care alone. At 3 years, the magnitude of change from baseline to 3 years significantly favored the investigational device compared to control treatments. Investigational subjects discontinued treatment at a far lower rate compared to control subjects. Investigational subjects who underwent a device exchange or repositioning procedure were able to continue therapy benefit with the medial meniscus prosthesis. In all KOOS subscales, the investigational subjects experienced superior improvements and outcomes at 3 years compared to non-surgical care subjects.

HTX-011 in Combination with Multimodal Analgesic Regimen Minimized Severe Pain and Opioid Use after Total Knee Arthroplasty in an Open-Label Study

Total knee arthroplasty (TKA) can be associated with significant postoperative pain despite multimodal analgesic (MMA) protocols, and most patients require the use of opioids postoperatively. HTX-011 is a dual-acting local anesthetic containing bupivacaine and low-dose meloxicam in an extended-release polymer. In a prior randomized controlled trial (RCT), HTX-011 reduced pain and opioid use through 72 hours after TKA compared with bupivacaine hydrochloride. This open-label study (NCT03974932) evaluated the efficacy and safety of HTX-011 combined with an MMA regimen in patients undergoing TKA under spinal anesthesia. All patients received intraoperative HTX-011 (400 mg bupivacaine/12 mg meloxicam) in combination with an MMA regimen consisting of preoperative acetaminophen, celecoxib, and pregabalin and postoperative acetaminophen and celecoxib until discharge. Opioid rescue was allowed upon patient request for additional pain control. Pain scores, opioid consumption, discharge readiness, and adverse events were recorded. Fifty-one patients were treated. Compared with the prior RCT, HTX-011 with this MMA regimen further lowered pain scores and reduced opioid use. Mean patient-reported pain scores remained in the mild range, and 82% of patients or more did not experience severe pain at any individual time point through 72 hours after surgery. Mean total opioid consumption was low over 72 hours: 24.8 morphine milligram equivalents (1-2 tablets of oxycodone 10 mg/day). Approximately 60% of patients were ready for discharge by 12 hours, and 39% were discharged without an opioid prescription and did not call back for pain management. The treatment regimen was well tolerated, and no added risk was observed with the addition of MMA. HTX-011 with an MMA regimen reduced postoperative pain and opioid use following TKA.

POS0277 ANABOLIC EFFECT OF LNA043, A NOVEL DISEASE-MODIFYING OSTEOARTHRITIS DRUG CANDIDATE: RESULTS FROM AN IMAGING-BASED PROOF-OF-CONCEPT TRIAL IN PATIENTS WITH FOCAL ARTICULAR CARTILAGE LESIONS

Background:

LNA043 is a modified, recombinant version of the human angiopoietin-like 3 (ANGPTL3) protein acting directly on cartilage-resident cells to transmit its cartilage anabolic effect. A first-in-human study previously demonstrated the favourable safety profile and the modulation of several pathways involved in cartilage homeostasis and osteoarthritis (OA)1. A previous proof-of-mechanism imaging study used high field (7 Tesla) magnetic resonance imaging (MRI) to show formation of hyaline-like tissue after a single injection of 20 mg LNA043 (unpublished data).

Objectives:

To evaluate non-invasively the chondro-regenerative capacity of multiple intra-articular (i.a.) injections of LNA043 in patients with articular cartilage lesions in the knee (NCT03275064).

Methods:

This was a randomised, double-blind, placebo (PBO)-controlled, proof-of-concept study in patients with a partial thickness cartilage lesion. In total, 58 patients (43 [20 mg LNA043]; 15 [PBO]), stratified by lesion type (condylar or patellar) were treated with 4 weekly i.a. injections. The primary endpoint was T2 relaxation time measurement as a marker of collagen fiber network, and cartilage lesion-volume was a secondary endpoint, both using 3-Tesla MRI. Assessments were performed at baseline, weeks (wks) 8, 16, 28 and 52 (the latter in 23/58 patients). While lesion-volume for the secondary endpoint was determined from manually segmented images, the cartilage volume of 21 sub-regions spanning the entire knee was also measured from 3D isotropic MR images employing an automated segmentation prototype software (MR Chondral Health 2.1 [MRCH], Siemens Healthcare)2. An exploratory analysis evaluated the treatment effect for the additive volume of the 3 subregions in the weight-bearing area of the medial femur.

Results:

No change in T2 relaxation time was detected between treatment and PBO groups. Manual segmentation showed continuous filling of the cartilage lesions up to wk 28 in LNA043-treated patients with femoral lesions (p=0.08, vs PBO) while no effect was detected for patients with patellar lesions. Given the limitations of measuring small, irregularly shaped lesions with manual image-analysis, the MRCH approach was used (Figure 1). In the medial femoral weight-bearing region, refilling was detected over time (Δ=123 mm3 at wk 28, N= 37, p= 0.05). No overgrowth was detected in the lateral femoral condyles without cartilage damage. The overall safety profile was favourable; only mild/moderate local reactions were reported, including a higher incidence of joint swelling (9.3% vs 0%) and arthralgia (11.6% vs 6.7%) for LNA043 vs PBO resolving spontaneously or with paracetamol/NSAIDs. No anti-drug antibodies were detected.

Conclusion:

Treatment with 4 weekly i.a. injections of 20 mg LNA043 resulted in regeneration of damaged cartilage in patients with femoral articular cartilage lesions. Automated measurement of cartilage volume in the femoral index region was able to detect a relevant treatment effect and was found to be more sensitive than the manual segmentation method. No sign of cartilage overgrowth was observed in healthy femoral regions. A Phase 2b study in patients with mild to moderate knee OA is in preparation.

References:

[1]Scotti et al. ACR Convergence 2020; Abstract #1483

[2]Juras et al. Cartilage 2020; Sep 29:1-12

Disclosure of Interests:

Siegfried Trattnig: None declared, Celeste Scotti Shareholder of: Novartis, Employee of: Novartis, Didier Laurent Shareholder of: Novartis, Employee of: Novartis, Vladimir Juras: None declared, Scott Hacker Grant/research support from: Novartis, Brian Cole: None declared, Libor Pasa: None declared, Roman Lehovec: None declared, Pavol Szomolanyi: None declared, Esther Raithel Employee of: Siemens Healthcare GmbH, Franziska Saxer Shareholder of: Novartis, Employee of: Novartis, Jens Praestgaard Shareholder of: Novartis, Employee of: Novartis, Fabiola La Gamba Shareholder of: Novartis, Employee of: Novartis, José L. Jiménez Employee of: Novartis, David Sanchez Ramos Shareholder of: Novartis, Employee of: Novartis, Ronenn Roubenoff Shareholder of: Novartis, Employee of: Novartis, Matthias Schieker Shareholder of: Novartis, Employee of: Novartis

The tibial cut in total knee arthroplasty influences the varus alignment, the femoral roll-back and the tibiofemoral rotation in patients with constitutional varus

PURPOSE

Different alignment types for a better outcome after TKA were described. However, it is not clear how kinematic alignment influences knee joint kinematic. The purpose of this study was to analyze whether adapted tibial cuts in constitutional varus knees affect knee joint kinematics regarding femoral roll-back, varus/valgus angle, and femorotibial rotation.

METHODS

Seven cadaveric knees with constitutional varus alignment were examined in the native state and after implantation of a cruciate retaining (CR)-TKA with 0°, 3° and 6° tibia cuts using an established knee joint simulator. The effects of varus alignment on femorotibial rollback and rotation was determined. In addition, the native knee joint and different tibial cuts in CR-TKA were compared with Student's t test.

RESULTS

Total knee replacement with a 3° and 6° varus tibia cut had the greatest varus deviation to the native knee (mean 1.6° ± 0.09°, respectively); while, knees with a 0° (mean 0.2° ± 0.01°) tibia cut were most similar to the constitutional varus knee joint. The femoral roll-back in the medial compartment was increased in the native knee (5.7-12.5 mm). A 6° varus cut had a restricted translation in the medial compartment (2-3.2 mm). In the lateral compartment, the extensive translation was observed with a 0° varus cut, followed by 3° and 6° and the native knee. All cuts showed significantly different mean values. Only the cuts at 3° and at 6° in the medial compartment and the cuts at 0° and at 3° in the lateral compartment did not differ significantly. In respect to tibiofemoral rotation, 0° and 3° varus cuts across all loads had the least difference to the native knee (3.4°), with a 0° varus cut showing a higher absolute internal rotation of the tibia than the native knee. Changes in knee kinematics of the tibiofemoral rotation showed significantly different mean values.

CONCLUSION

The potentially improved outcome parameters in TKA with adapted tibia cuts in constitutional varus knees cannot be completely explained by the changes to knee kinematics. Mechanical alignment seems to result in more balanced load distribution and kinematics more closely resembling the native knee. From a kinematic point of view, it is not recommended to place the tibia in more than 3° of varus.

LEVEL OF EVIDENCE

Biomechanical study.

The tibial cut influences the patellofemoral knee kinematics and pressure distribution in total knee arthroplasty with constitutional varus alignment

PURPOSE

The current literature suggests that kinematic total knee arthroplasty (kTKA) may be associated with better outcome scores in patients with constitutional varus alignment. The underlying patellofemoral kinematic changes (patella tilting and patella tracking) and patellofemoral pressure distribution have not yet been described. The present study compared the effects of different tibial cuts, as used in kTKA, on patellofemoral knee kinematics and the pressure distribution, in addition to comparisons with the natural constitutional varus knee.

METHODS

Seven cadaveric knee joints with constitutional varus alignment were examined in the native state and after 0°, 3°, or 6° tibial cut cruciate-retaining (CR)-TKA using an established knee joint simulator. The effects on patella rotation/patella tilting, patellofemoral pressure, and patellofemoral length ratios (= patella tracking) were determined. In addition, the natural knee joint and different tibial cuts in CR-TKA were compared (Student's t test).

RESULTS

In the patellofemoral joint, 6° CR-TKA was associated with the greatest similarity with the natural constitutional varus knee. By contrast, knees subjected to 0° CR-TKA exhibited the largest deviations of patellar kinematics. The smallest difference compared with the natural knee joint concerning patella tilting was found for 6° CR-TKA (mean 0.4°, p < 0.001), and the largest difference was noted for 0° CR-TKA (mean 1.7°, p < 0.001). Concerning patellofemoral pressure, 6° CR-TKA resulted in outcomes most similar to the natural knee joint, featuring a mean difference of 3 MPa. The largest difference from the natural knee joint was identified for 0° CR-TKA, with an average difference of 8.1 MPa (p < 0.001; total mean 17.7 MPa). Meanwhile, 3° and 6° CR-TKA induced medialization of the patella, with the latter inducing the largest medialization value of 4.5 mm at 90° flexion.

CONCLUSIONS

The improved outcome parameters in kTKA described in the literature could be attributable to the similar kinematics of the patellofemoral joint relative to the normal state. The current study confirmed the similar kinematics between the native constitutional varus knee joint and knee joints subjected to 3° or 6° CR-TKA (patellofemoral rotation/patella tilting and patella pressure). Conversely, there was pronounced medialization of the patella following 6° CR-TKA. Patella pressure and patella tilting are described in the literature as possible causes of anterior knee pain after TKA, whereas medialization of the patella, which is also influenced by other causes, might play a subordinate role.

LEVEL OF EVIDENCE

V, Biomechanical study.

A Framework for Representation and Visualization of 3D Shape Variability of Organs in an Interactive Anatomical Atlas

Objectives: Computerized anatomical 3D atlases allow interactive exploration of the human anatomy and make it easy for the user to comprehend complex 3D structures and spatial interrelationships among organs. Besides the anatomy of one reference body inter-individual shape variations of organs in a population are of interest as well. In this paper, a new framework for representation and visualization of 3D shape variability of anatomical objects within an interactive 3D atlas is presented.

Methods: In the VOXEL-MAN atlases realistic 3D visualizations of organs in high quality are generated for educational purposes using volume-based object representations. We extended the volume-based representation of organs to enable the 3D visualization of organs’ shape variability in the atlas. Therefore, the volume-based representation of the inner organs in the atlas is combined with a medial representation of organs of a population creating a compact description of shape variability.

Results: With the framework developed different shape variations of an organ can be visualized within the context of a volume-based anatomical model. Using shape models of the kidney and the breathing lung as examples we demonstrate new possibilities such an approach offers for medical education. Furthermore, attributes like gender, age or pathology as well as shape attributes are assigned to each shape variant which can be used for selecting specific organs of the population.

Conclusions: The inclusion of anatomical variability in a 3D interactive atlas presents considerable challenges, since such a system offers the chance to explore how anatomical structures vary in large populations, across age, gender and races, and in different disease states. The framework presented is a basis for the development of specialized variability atlases that focus e.g. on specific regions of the human body, groups of organs or specific topics of interest.

Proteome analysis identifies L1CAM/CD171 and DPP4/CD26 as novel markers of human skin mast cells

BACKGROUND

The function of skin mast cells has been well documented in IgE-mediated allergic reactions, whereas other mast cell functions are poorly defined. This study aimed at identifying novel mast cell proteins by proteome analysis of primary human skin mast cells.

METHODS

The proteome of skin mast cells was compared to other cell types and analyzed using bioinformatics. The expression and function of two proteins hitherto not described in skin mast cells was investigated in isolated mast cells as well as in mast cells in situ.

RESULTS

Within the mast cell proteome, we identified 49 highly expressed proteins previously not described in mast cells; 21 of these proteins were found to be selectively expressed in mast cells. Two proteins, the neural cell adhesion molecule L1 and dipeptidyl peptidase 4, were further studied. L1 was found to be highly expressed in mast cells in normal, psoriasis, and mastocytosis skin. Dipeptidyl peptidase 4 was found to be expressed in mast cells in normal, psoriasis, and mastocytosis skin as well as in bone marrow mast cells in patients with systemic mastocytosis. In normal skin, mast cells were identified as a major source of dipeptidyl peptidase 4 and we also found that skin mast cells and fibroblasts secrete an active form of this enzyme.

CONCLUSIONS

In a systematic proteomics approach we identified two novel mast cell proteins potentially relevant to skin homeostasis: neural cell adhesion molecule L1 and dipeptidyl peptidase 4.

Monitoring of unfractionated heparin with rotational thrombelastometry using the prothrombinase-induced clotting time reagent (PiCT®)

PURPOSE

To achieve sufficient and safe anticoagulation with unfractionated heparin (UFH) a close and reliable drug monitoring is necessary. In general, the activated partial thromboplastin time (APTT) is used for this purpose. In acute phase response, however, the APTT test procedure might be unreliable e.g. with false low results in the presence of elevated factor VIII. In this so called heparin resistance, measurement of anti-Xa activity is recommended over APTT to avoid potentially harmful dose escalation. A combination of anti-Xa measurement and global hemostatic testing with ROTEM® employing the anti-Xa sensitive PiCT® reagent showed high correlation with enoxaparin levels. This test modification could also be suitable for monitoring UFH. Aim of the study was to evaluate the correlation between PiCT®-ROTEM® and levels of UFH.

METHODS

In this in-vitro study blood samples from healthy volunteers were spiked with UFH and subjected to different ROTEM® tests.

RESULTS

There was a linear correlation between UFH level and clotting time (CT) in the PiCT®-ROTEM® test with an excellent correlation coefficient of 0.92. Additional endpoints showed similar results (PiCT®-ROTEM® MaxVel r = -0.85 and PiCT®-ROTEM® t_MaxVel r = 0.88).

CONCLUSIONS

As a point-of-care applicable tool ROTEM® is immediately at hand. If further clinical studies confirm sensitivity in heparin resistance, PiCT®-ROTEM® could permit rapid UFH dose adjustments especially required in critical illness with acute phase response.

Irradiated cultured apoptotic peripheral blood mononuclear cells regenerate infarcted myocardium

BACKGROUND

Acute myocardial infarction (AMI) is followed by post AMI cardiac remodelling, often leading to congestive heart failure. Homing of c-kit+ endothelial progenitor cells (EPC) has been thought to be the optimal source for regenerating infarcted myocardium.

METHODS

Immune function of viable peripheral blood mononuclear cells (PBMC) was evaluated after co-culture with irradiated apoptotic PBMC (IA-PBMC) in vitro. Viable PBMC, IA-PBMC and culture supernatants (SN) thereof were obtained after 24 h. Reverse transcription polymerase chain reaction and enzyme-linked immunosorbent assay were utilized to quantify interleukin-8 (IL-8), vascular endothelial growth factor, matrix metalloproteinase-9 (MMP9) in PBMC, SN and SN exposed fibroblasts. Cell suspensions of viable- and IA-PBMC were infused in an experimental rat AMI model. Immunohistological analysis was performed to detect inflammatory and pro-angiogenic cells within 72 h post-infarction. Functional data and determination of infarction size were quantified by echocardiography and Elastica van Gieson staining.

RESULTS

The IA-PBMC attenuated immune reactivity and resulted in secretion of pro-angiogenic IL-8 and MMP9 in vitro. Fibroblasts exposed to viable and IA-PBMC derived SN caused RNA increment of IL-8 and MMP9. AMI rats that were infused with IA-PBMC cell suspension evidenced enhanced homing of endothelial progenitor cells within 72 h as compared to control (medium alone, viable-PBMC). Echocardiography showed a significant reduction in infarction size and improvement in post AMI remodelling as evidenced by an attenuated loss of ejection fraction.

CONCLUSION

These data indicate that infusion of IA-PBMC cell suspension in experimental AMI circumvented inflammation, caused preferential homing of regenerative EPC and replaced infarcted myocardium.

Pro-inflammatory interleukin-18 and Caspase-1 serum levels in liver failure are unaffected by MARS treatment

BACKGROUND

The pro-inflammatory cytokine IL-18 and its activator Caspase-1 are involved in acute liver failure and acute-on-chronic-liver-failure. In acute liver failure and acute-on-chronic-liver-failure, the MARS system has been used to support liver function. Enhancement of IL-18, as seen in other extracorporeal-support systems like hemodialysis might thus have mitigated beneficial effects of the MARS system in acute hepatic failure.

PATIENTS AND METHODS

We measured serum concentrations of IL-18 and Caspase-1 in 10 patients with acute liver failure and 10 patients suffering from acute-on-chronic-liver-failure, who were all treated with MARS. Thirteen patients suffering from chronic hepatic failure and 15 healthy individuals served as controls. Data are given as mean with 95% CI.

RESULTS

Baseline IL-18 serum concentrations were significantly increased in acute liver failure and acute-on-chronic-liver-failure patients as compared to chronic hepatic failure (P=0.0039 and P=0.0011, respectively) and controls (P=0.0028 and P=0.0014, respectively). Caspase-1 serum concentrations were as well significantly elevated in the acute liver failure and acute-on-chronic-liver-failure groups as compared to chronic hepatic failure patients (P=0.0039 and P=0.0232, respectively) and controls P<0.0001 and P<0.0007, respectively). IL-18 and Caspase-1 did not change significantly during MARS treatment in acute liver failure and acute-on-chronic-liver-failure patients.

CONCLUSIONS

MARS had no effect on IL-18 and Caspase-1 serum concentrations in acute liver failure and acute-on-chronic-liver-failure, providing no evidence of harmful effects by the increase of these potentially hepatocidal cytokines.

T cell senescence and contraction of T cell repertoire diversity in patients with chronic obstructive pulmonary disease

Pathogenetic mechanisms leading to chronic obstructive pulmonary disease (COPD) remain poorly understood. Because clonogenic T cells (CD4(+)CD28(null)) were shown to be increased in autoimmune diseases we hypothesized that CD4(+)CD28(null) T cells play a role in COPD. Here we describe that enhanced presence of CD4(+)CD28(null) cells is associated with impaired lung function. Sixty-four patients and controls were included. T cell phenotype was analysed using flow cytometry. Enzyme-linked immunosorbent assays were utilized to determine cytokines. Statistical evaluations were performed using non-parametric group comparisons and correlations. A logistic regression model was used to determine predictive values of CD4(+)CD28(null) in the diagnosis of COPD. Populations of CD4(+) T cells lacking surface co-stimulatory CD28 were enlarged significantly in evaluated patients when compared with controls. Natural killer (NK)-like T cell receptors (CD94, 158) and intracellular perforin, granzyme B were increased in CD4(+)CD28(null) cells. Cytokine production after triggering of peripheral blood mononuclear cells (PBMCs) was elevated in patients at early disease stages. Receiver operating characteristic curve plotting revealed that presence of CD4(+)CD28(null) T cells has a diagnostic value. These CD4(+)CD28(null) T cells show increased expression of NK-like T cell receptors (CD94, 158) and intracellular perforin and granzyme B. Furthermore, triggering of PBMCs obtained from patients with mild COPD led to increased interferon-gamma and tumour necrosis factor-alpha production in vitro compared with controls. Our finding of increased CD4(+)CD28(null) T cells in COPD indicates that chronic antigen exposure, e.g. through contents of smoke, leads to loss of CD28 and up-regulation of NK cell receptors expression on T cells in susceptible patients.

Bevacizumab protects against sinusoidal obstruction syndrome and does not increase response rate in neoadjuvant XELOX/FOLFOX therapy of colorectal cancer liver metastases

AIM

In patients suffering from colorectal cancer liver metastases, 5-fluorouracil-based chemotherapy plus oxaliplatin ensures superior response rates at the cost of hepatic injury. Knowledge about the consequences of bevacizumab on chemotherapy-induced hepatic injury and tumor response is limited.

METHODS

Resected liver specimens from patients of two prospective, non-randomized trials (5-fluorouracil/oxaliplatin+/-bevacizumab) were analyzed retrospectively. Hepatotoxicity to the non-tumor bearing liver was evaluated for sinusoidal obstruction syndrome, hepatic steatosis and fibrosis. Tumor response under chemotherapy was assessed according to Response Evaluation Criteria in Solid Tumors (RECIST).

RESULTS

Bevacizumab decreased the severity of the sinusoidal obstruction syndrome. Bevacizumab had no impact on hepatic steatosis and fibrosis. The addition of bevacizumab to chemotherapy had no effect on tumor response compared to combination chemotherapy alone.

CONCLUSIONS

This analysis shows that bevacizumab protects against the sinusoidal obstruction syndrome and thus provides the histological explanation of the safe use of bevacizumab prior to liver resection. Furthermore, we show that bevacizumab does not improve tumor response according to RECIST.

Secretion of soluble ST2 - possible explanation for systemic immunosuppression after heart surgery

BACKGROUND

Cardiopulmonary bypass is known to affect cytokine release leading to a generalized endogenous immune reaction similar to that described in sepsis, without having been explored in great detail. Therefore we evaluated the anti- and pro-inflammatory cytokine responses after heart surgery.

METHODS

16 patients who underwent coronary artery bypass graft (CABG) surgery with extracorporeal circulation were included. ST2, IL-4 and IL-10 served as markers for TH2 cytokine response; IL-6, IL-8 and IFN-gamma as TH1 markers. Furthermore, total immunoglobulin subtype analysis (IgM, IgG, IgE) was performed.

RESULTS

Serum levels of soluble ST2 started to climb at 60 minutes (from 38 +/- 14 preoperatively to 1 480 +/- 890 pg/ml) and peaked 24 hours after surgery (13 360 +/- 2 840 pg/ml, P < 0.001). IL-10 reached a maximum at 60 minutes and returned to baseline levels 24 hours later. IL-6 and IL-8 levels peaked 60 minutes after surgery. IL-4 and IFN-gamma did not change. Only IgM showed a significant peak on day eight ( P < 0.001).

CONCLUSION

Our results demonstrate that CABG surgery induces a massive long-lasting secretion of ST2, a protein related to immune suppression.

Myocardial lipofuscin-laden lysosomes contain the apoptosis marker caspase-cleaved cytokeratin-18

BACKGROUND

Acute coronary syndrome is related to increased circulatory concentration of soluble apoptosis specific caspase-cleaved cytokeratin-18 (ccCK-18). Potential cardiac sources of this intermediate filament derivative have not been investigated to date.

MATERIALS AND METHODS

Paraffin embedded tissue of normal myocardium, and chronically damaged samples of ischaemic, congestive and hypertrophic cardiomyopathy were analysed by histology and by CK-8, CK-18, ccCK-18 immunohistochemistry (each group, n = 15). Antibody specificity of the ccCK-18 antibody M30 was checked by immunoblotting on lysed myocardium and enriched myocardial lysosomes.

RESULTS

ccCK-18 and CK-18 but not CK-8 were present in all forms of cardiomyopathy, most prominently in ischaemic cardiomyopathy while only traces were detectable immunohistochemically in normal myocardium. Weak CK-18 and strong ccCK-18 staining co-localized to lysosomes with cardiac age pigment lipofuscin. Weak staining of CK-18 was detected in the cytoplasm of coronary endothelia.

CONCLUSION

Our study reveals that cardiac lipofuscin-laden lysosomes contain ccCK-18, a marker of apoptosis and its precursor CK-18. This ccCK-18 pool might contribute to increased systemic levels of ccCK-18 in acute coronary syndrome thus monitoring myocardial damage.

Intravenous immunoglobulins induce CD32-mediated platelet aggregation in vitro

BACKGROUND

Intravenous immunoglobulins (IVIg) and cytomegalovirus immunoglobulins (CMVIg) are currently finding increased acceptance in clinical states of high immune activity and in transplant recipients. A rare side-effect of their application is intravascular thrombosis, which is thought to be related to pre-existing hyperviscosity. In a previous study we have shown that rabbit antithymocyte globulin causes platelet aggregation in vitro via the Fc IgG receptor (CD32).

OBJECTIVES

To investigate if IVIg and CMVIg have the potential to cause CD32-dependent platelet aggregation.

METHODS

The influence of CMVIg or IVIg on platelets pre-incubated with or without monoclonal antibody AT10 was studied in an aggregometer. Expression of platelet surface activation marker CD62P was determined by fluorescence-activated cell sorting analysis and presence of soluble CD40L (sCD40L) was evaluated by enzyme-linked immunosorbent assay. All in vitro experiments were performed using platelet concentrates from the blood bank, at therapeutic concentrations of immunoglobulins. Results Incubation of platelets with CMVIg and IVIg markedly induced platelet aggregation, and increased expression of CD62P and secretion of sCD40L. The capacity of CMVIg and IVIg to induce platelet aggregation was completely abrogated by adding the blocking antibody AT10 directed against the low-affinity Fc IgG receptor (CD32).

CONCLUSIONS

Our results suggest that CMVIg and IVIg solutions with activating Fc domains are able to bind CD32 on platelets and cause platelet aggregation in vitro. These results indicate a mechanism by which in vivo intravascular thrombosis may be explained and suggest caution with concomitant use of packed platelets and IVIg in autoimmune diseases in the clinical setting.

Patterns of hepatotoxicity after chemotherapy for colorectal cancer liver metastases

AIM

The aim of this study was to assess chemotherapy associated hepatotoxicity after 3 months' treatment and to correlate patterns of hepatotoxicity with perioperative morbidity.

METHODS

Liver specimens of 50 patients with liver metastases from colorectal cancer receiving XELOX or FOLFOX4 for six cycles and 13 specimens of non-chemotherapy patients subjected to liver resection were analyzed. Different patterns of hepatotoxicity were evaluated according to widely accepted pathohistological scores. Furthermore, the histomorphological findings were correlated with perioperative morbidity.

RESULTS

Steatosis grades did not differ among the chemotherapy treated groups and non-chemotherapy patients. Chemotherapy showed an independent effect on fibrosis stage. Age and chemotherapy were independently associated with sinusoidal dilatation. Centrilobular vein fibrosis correlated with administration of chemotherapy. Higher fibrosis stages were associated with increased transfusion requirements.

CONCLUSION

XELOX and FOLFOX4 do not correlate with the development of steatosis or steatohepatitis. We do not detect a difference in liver injury between the XELOX and FOLFOX4 group. Although 5-fluorouracil based chemotherapy may cause profound changes in liver parenchyma, it can be safely applied. However, age and oxaliplatin predispose for the development of sinusoidal dilatation; therefore caution must be taken in old patients treated with oxaliplatin.

Cytomegalovirus hyperimmunoglobulin: mechanisms in allo-immune response in vitro

BACKGROUND

Cytomegalovirus hyperimmunoglobulin (CMVIg) containing drugs are routinely administered in cardiac transplantation for prophylaxis against CMV disease. Yet little is known about their influence on transplant relevant immune functions. The aim of this study was to evaluate the effect of CMVIg on cellular immunity in in vitro experiments and to define their role in tolerance inducing mechanisms.

MATERIALS AND METHODS/RESULTS

CMVIg reduces proliferation in mixed lymphocyte reactions and anti-CD3 blastogenesis assays and is related to decreased production of immune modulating cytokines interleukin (IL)-2, interferonr (IFNgamma), IL-10. This antiproliferative effect is associated with a cell-cycle arrest in the G0/G1 phase and induction of apoptosis in CD8+ and natural killer cells. Co-incubation with CMVIg causes down-regulation of cell bound immunoglobulin and FcgammaRIII surface expression on natural killer cells and leads to attenuation of antibody dependent cellular cytotoxicity effector functions.

CONCLUSIONS

We conclude that CMVIg induces immunological features on leukocytes in vitro that are known to be related to tolerance induction. Our observations extend the current concept of CMVIg as passive CMV prophylaxis to a therapeutic drug compound capable of reducing allogeneic immune response.

Elevated levels of interleukin-1beta-converting enzyme and caspase-cleaved cytokeratin-18 in acute myocardial infarction

BACKGROUND

Systemic inflammation and apoptosis-specific immune activation play a major role in acute coronary syndromes (ACS) including acute myocardial infarction (AMI). The role of systemic and coronary obtained inflammatory plasma protein interleukin-1beta precursor (IL-1betap), IL-1beta-converting enzyme (ICE) and the apoptosis-specific caspase-cleaved cytokeratin-18 (ccCK-18) are not known in ACS.

MATERIALS AND METHODS

Plasma samples were obtained from stable angina (SA, n = 34), unstable angina (UA, n = 37) and patients with AMI (n = 39). Coronary blood was acquired by means of thrombectomy devices (X-sizer) in AMI patients. IL-1betap, ICE and ccCK-18 were determined by enzyme-linked immunosorbent assay (ELISA). Group comparisons were evaluated by parametric Tukey test. Multivariate logistic regression analysis was performed to determine predictive values of IL-1betap, ICE and ccCK-18 as compared to creatine kinase (CK) and troponin T (TnT) in order to relate these markers with the occurrence of myocardial damage.

RESULTS

IL-1betap, ICE and ccCK-18 were identified to be significantly altered in the peripheral blood of patients suffering from AMI as compared to SA and UA. ROC curves were plotted and revealed that ccCK-18 is a novel sensitive marker for the detection of myocardial damage as compared to TnT or CK. (AUC ccCK-18 0.925, TnT AUC 0.62 and CK AUC 0.858.) Moreover, ICE and ccCK-18 were significantly increased at the site of coronary occlusion as compared to peripheral blood samples in AMI patients (both P < 0.001).

CONCLUSION

Our data suggest that ACS is related to increased concentration of systemic soluble ICE and ccCK-18. Moreover, soluble ccCK-18 was identified to be a superior marker as compared to TnT or CK, for detection of myocardial damage.

Recovery from giant cell myocarditis with ECMO support and utilisation of polyclonal antithymocyte globulin: a case report

Giant cell myocarditis (GCM) is a rare and frequently fatal disorder. Patients suffer of ventricular arrhythmias or congestive heart failure. Here we describe a patient with cardiogenic shock and histological verified GCM. The patient was saved by implantation of extracorporeal membrane oxygeneation (ECMO) device and concomitant application of Rabbit antithymocyte globuline (rATG, Thymoglobulin, Sangstat), cyclosporine, and steroids in the acute event. 12 months after the crisis the patient evidences NYHA class I heart function and only a moderate impairment of heart function (EF 55%). The novel utilisation of ECMO in GCM related cardiogenic shock and application of rATG have prooven life-saving in this patient. Studies utilizing rATG in the treatment of GCM are warrented.

EUS Meets Voxel-Man: three-dimensional anatomic animation of linear-array endoscopic ultrasound images

Endoscopic ultrasonography (EUS) is a widely used imaging modality in gastroenterology. The development of linear-array endoscopic ultrasound transducers, with facilities for EUS-guided diagnostic and therapeutic procedures, led to increasingly widespread use in different areas of the body. Examiners need to have excellent knowledge of anatomy. Orientation in linear EUS is more difficult and the learning curve is long. In an effort to shorten the training, reducing the risk to the patient and to allow a faster learning of the basic anatomic structures EUS meets VOXEL-MAN, an interactive three-dimensional anatomic simulation program has been developed for linear EUS for the purposes of private and independent study.

Smoking, dietary, and breast and cervical cancer screening knowledge and screening practices of employees in an urban medical center

This paper reports results of a survey of 500 health care workers in a private New York City Hospital that assessed knowledge and behaviors in the areas of smoking and cancer, diet and cancer, and breast and cervical cancer screening. Given the small number of knowledge items, the results indicated good knowledge concerning diet and cancer, smoking and cancer, and mammography and Pap test guidelines. Conformity with American Cancer Society guidelines for Pap testing was comparable to national figures, but with women over 50 as likely to obtain Pap smears as younger women. Conformity with mammography guidelines was excellent, although compliance with breast self-examination recommendations was low (25.4%). Of female employees over age 50, 87.4% had ever had mammography and 77.6% reported yearly mammography. Only 19% of the respondents admitted to current smoking. Although methodologic differences made comparison of knowledge of diet and cancer with the work of others difficult, knowledge of the risks of smoking was comparable to levels found in other studies.

[Early vectorcardiographic diagnosis of rejection in long-term follow-up of heart transplantation]

A series of 194 transplant subjects was followed-up by over 2,600 vectorcardiograms. Several cases of rejection were chosen among the most patent and best documented cases (eight cases of acute rejection and seven cases of chronic rejection) and 15 control cases where all tests, including the vectorcardiogram, had always remained negative. Two criteria of rejection were used, i.e. the amplitude of the left maximum QRS vector less than 1.10 mV and relative right spatial area greater than 35 per cent. By accumulating all traces for each patient, recorded during and outside the rejection phase, it was found that the mean of the individual means was 0.96 mV for the left amplitude in cases of rejection versus 1.74 mV in the control group, and 44 versus 22 per cent for the right area. The first trace which, on the curves showing the progress of each patient, was likely to signal acute or chronic rejection always had a left amplitude less than 1 mV (mean 0.89 mV) and a right area greater than 33 per cent (mean 45%). The first suspicious trace always preceded the detection of signs by echography or biopsy (except in one case where it occurred at the same time). The interval varied from 16 to 112 days in five cases of rejection assessed as acute, and from 63 to 600 days in seven cases of chronic rejection. There was no echographic control in two other cases, but death occurred 45 and 63 days after the first vectorcardiographic signs. The vectorcardiogram improves after recovery from acute rejection.(ABSTRACT TRUNCATED AT 250 WORDS)

Independent regulation of beta 1- and beta 2-adrenoceptors

1 The down-regulation of beta-adrenoceptors has been postulated as a biochemical marker of antidepressant efficacy. Here we demonstrate that chronic treatment with desipramine down-regulates beta 1-adrenoceptors in rat cerebral cortex and that beta-adrenoceptor subtypes can be independently regulated by treatment with different beta-adrenoceptor agonists. 2 Desipramine, (+/-)-clenbuterol, prenalterol, corwin (20 mg kg-1 daily) and corwin (10 mg kg-1 daily) were administered to male, Sprague-Dawley rats, over eight days, by means of osmotic Alzet pumps placed subcutaneously and removed 24 h before analysis. Control rats received vehicle only. The beta 1- and beta 2-adrenoceptor populations were measured in cerebral cortex by a modified (-)-[125I]-pindolol receptor binding assay. 3 The conventional antidepressant, desipramine, preferentially down-regulated beta 1-adrenoceptors whereas the non-selective beta-adrenoceptor agonist (+/-)-clenbuterol preferentially down-regulated beta 2-adrenoceptors. The beta 1-selective partial agonist, prenalterol, up-regulated beta 1-adrenoceptors perhaps acting more as an antagonist than as an agonist. Finally, neither dose of corwin had any significant effect on beta-adrenoceptor number.