Sébastien Hagmann

The spectrum of systemic immune alterations after murine focal ischemia: immunodepression versus immunomodulation.

Background and Purpose— Therapeutic modification of the postischemic immune processes is a key target of current experimental stroke research. For successful translation into the clinical setting, experimental studies must account for the impact of different strokes on the immune system including susceptibility to infection. Herein, we characterize the impact of 3 ischemia models on systemic immunological and microbiological parameters. Methods— In C57Bl/6 mice (n=235), the middle cerebral artery was occluded (MCAO) either permanently by distal coagulation or transiently by an intraluminal filament for 30 minutes or 90 minutes. Differential leukocyte counts were performed in blood and lymphatic organs. Lymphocyte subpopulations and apoptotic cells were characterized by flow cytometry. Blood cytokine concentrations were measured by ELISA. Microbiological cultures were grown from blood and lung samples. Results— Only extensive infarcts induced leukopenia 24 hours, 3 days and 7 days after MCAO and decreased lymphocyte counts in spleen, lymph nodes and thymus. In contrast, small infarcts led to no significant changes in differential blood count or reduction of overall cell counts in lymphatic organs. Splenic lymphocyte apoptosis and blood cytokine production was significantly increased after extensive lesions compared to mild ischemia. Hypothermia and weight loss occurred only in mice with large infarcts which also suffered from pneumonia and sepsis. In contrast to infarct size, location and side of the infarct did not affect physiological parameters and immune cell alterations. Conclusions— Postischemic systemic immunomodulation and infectious complications differ substantially among stroke models. Translational studies of immunomodulatory therapies for stroke must account for this heterogeneity.

Long-term outcome of femoral derotation osteotomy in children with spastic diplegia

Satisfactory short-term results after femoral derotation osteotomy (FDO) for the treatment of internal rotation gait in cerebral palsy have been reported by various authors. However, there are only a few longer-term studies reporting results 5 years after FDO and these are not in agreement. There are no reports on the clinical course beyond the pubertal growth spurt. 33 children with diplegia (n=59 legs, age: 10.5±3.6 years) and internally rotated gait were examined pre- (E0), 1 year (E1), 3±1 (E2) and 9±2 (E3) years after distal (27 legs) or proximal (32 legs) FDO as part of multilevel surgery, using standardized clinical exam and 3D gait-analysis at all examinations. The amount of intra-operative derotation averaged 25°. ANOVA was used for statistics (p<0.05). Mean hip internal rotation in stance at E0 of 17.3° was significantly changed to 1.0° of external rotation at E1 and was maintained at 4.2° at E3. The same clinical course was found for foot progression angle. The mid-point of passive hip rotation at E0 was 21°. This was significantly decreased to 6° at E1 and showed a small but significant increase reaching 12° at E3. The results of this study showed a good overall correction of internally rotated gait following FDO. These improvements were maintained at long-term follow-up after the pubertal growth spurt. Recurrence was observed in some cases with overall severe deterioration. In those patients persistent dynamic factors leading to recurrence should be further investigated.

First-generation autologous chondrocyte implantation in patients with cartilage defects of the knee: 7 to 14 years' clinical and magnetic resonance imaging follow-up evaluation.

PURPOSE The purpose of this study was to evaluate the overall long-term improvement of autologous chondrocyte implantation (ACI) treatment in terms of patient satisfaction, clinical assessment, and magnetic resonance imaging (MRI) evaluation. Furthermore, we aimed to assess the impact of independent variables on clinical outcomes and patient satisfaction. METHODS We evaluated 23 patients (mean age, 30.5 ± 8.2 years) with full-thickness chondral lesions of the distal femur who underwent first-generation ACI with periosteum between 1997 and 2004. The Lysholm score, Tegner activity score, subjective International Knee Documentation Committee score, numeric rating scale score, and Short Form 36 score were used for clinical assessment preoperatively, at 1 year postoperatively, and at 7 to 14 years (mean, 9.9 years) after surgery. MRI was performed to evaluate the cartilage preoperatively and at final follow-up, by use of the Magnetic Resonance Observation of Cartilage Repair Tissue (MOCART) score. RESULTS ACI resulted in a substantial improvement in all clinical outcome parameters, even as much as 14 years after implantation, although a small deterioration was noticed between intermediate and final evaluations in some outcome parameters. Of the patients, 73.1% stated that they would undergo the operation again. Younger patients with a shorter duration of preoperative symptoms and smaller defect sizes benefited most. MRI findings confirmed complete defect filling in 52.3% of the patients at final follow-up. CONCLUSIONS Our long-term results confirm that first-generation ACI is an effective treatment for large full-thickness chondral and osteochondral lesions of the knee joint. Younger patients with a shorter duration of preoperative symptoms and smaller defect size benefited most in our study. LEVEL OF EVIDENCE Level IV, therapeutic case series.

Oxygen therapy in permanent brain ischemia: Potential and limitations

BACKGROUND Both normobaric (NBO) and hyperbaric (HBO) oxygen therapy are protective in transient cerebral ischemia. In contrast, in permanent ischemia models, which reflect the majority of clinical strokes, the effectiveness of NBO is unknown, and the effectiveness of HBO is controversial. The goals of the present study were to compare both oxygen therapies in 2 models of permanent ischemia, to study the effect of time window, and to evaluate the combination of both oxygen therapies. METHODS Distal or proximal permanent occlusion of middle cerebral artery (MCAO) was induced by coagulation or filament, respectively. Mice received air, NBO, a single or repeated HBO (3 ata) treatments. Infarct sizes were quantified at 7 days (coagulation) and 24 h (filament), respectively. RESULTS Following MCA coagulation, infarct volume was 12.9+/-1.6 mm3 in mice breathing air. When started 45 min or 120 min after MCAO, NBO (10.8+/-2.2) and significantly more potently HBO (7.8+/-0.9) reduced infarct size. Repeated HBO treatments had no additional effect (8.3+/-2.3). HBO also significantly decreased TUNEL cell staining at 24 h. Combination of 60 min NBO plus 60 min HBO resulted in smaller cortical infarcts (8.7+/-1.5) than 120 min NBO alone (11.1+/-3.2). In contrast, infarct volumes in filament-induced permanent MCAO did not differ among rodents receiving air (50+/-24 mm3), NBO (48+/-16), or HBO (46+/-21). After filament-induced transient MCAO, however, HBO reduced infarct volume significantly. CONCLUSIONS NBO and more effectively HBO protect the brain against permanent cortical ischemia. In extensive focal ischemia, however, oxygen therapy is only effective in case of early recanalization.

Different culture media affect growth characteristics, surface marker distribution and chondrogenic differentiation of human bone marrow-derived mesenchymal stromal cells

BackgroundBone marrow-derived mesenchymal stromal cells (BM-MSCs) play an important role in modern tissue engineering, while distinct variations of culture media compositions and supplements have been reported. Because MSCs are heterogeneous regarding their regenerative potential and their surface markers, these parameters were compared in four widely used culture media compositions.MethodsMSCs were isolated from bone marrow and expanded in four established cell culture media. MSC yield/1000 MNCs, passage time and growth index were observed. In P4, typical MSC surface markers were analysed by fluorescence cytometry. Additionally, chondrogenic, adipogenic and osteogenic differentiation potential were evaluated.ResultsGrowth index and P0 cell yield varied importantly between the media. The different expansion media had a significant influence on the expression of CD10, CD90, CD105, CD140b CD146 and STRO-1. While no significant differences were observed regarding osteogenic and adipogenic differentiation, chondrogenic differentiation was superior in medium A as reflected by GAG/DNA content.ConclusionsThe choice of expansion medium can have a significant influence on growth, differentiation potential and surface marker expression of mesenchymal stromal cells, which is of fundamental importance for tissue engineering procedures.

CD4+CD25+/highCD127low/- regulatory T cells are enriched in rheumatoid arthritis and osteoarthritis joints—analysis of frequency and phenotype in synovial membrane, synovial fluid and peripheral blood

IntroductionCD4+CD25+/highCD127low/- regulatory T cells (Tregs) play a crucial role in maintaining peripheral tolerance. Data about the frequency of Tregs in rheumatoid arthritis (RA) are contradictory and based on the analysis of peripheral blood (PB) and synovial fluid (SF). Because Tregs exert their anti-inflammatory activity in a contact-dependent manner, the analysis of synovial membrane (SM) is crucial. Published reports regarding this matter are lacking, so we investigated the distribution and phenotype of Tregs in concurrent samples of SM, SF and PB of RA patients in comparison to those of osteoarthritis (OA) patients.MethodsTreg frequency in a total of 40 patients (18 RA and 22 OA) matched for age and sex was assessed by flow cytometry. Functional status was assessed by analysis of cell surface markers representative of activation, memory and regulation.ResultsCD4+ T cells infiltrate the SM to higher frequencies in RA joints than in OA joints (P = 0.0336). In both groups, Tregs accumulate more within the SF and SM than concurrently in PB (P < 0.0001). Relative Treg frequencies were comparable in all compartments of RA and OA, but Treg concentration was significantly higher in the SM of RA patients (P = 0.025). Both PB and SM Tregs displayed a memory phenotype (CD45RO+RA-), but significantly differed in activation status (CD69 and CD62L) and markers associated with Treg function (CD152, CD154, CD274, CD279 and GITR) with only minor differences between RA and OA.ConclusionsTreg enrichment into the joint compartment is not specific to inflammatory arthritis, as we found that it was similarly enriched in OA. RA pathophysiology might not be due to a Treg deficiency, because Treg concentration in SM was significantly higher in RA. Synovial Tregs represent a distinct phenotype and are activated effector memory cells (CD62L-CD69+), whereas peripheral Tregs are resting central memory cells (CD62L+CD69-).

Long-Term Results After Distal Rectus Femoris Transfer as a Part of Multilevel Surgery for the Correction of Stiff-Knee Gait in Spastic Diplegic Cerebral Palsy

BACKGROUND The evidence for distal rectus femoris transfer as a part of multilevel surgery for the correction of stiff-knee gait in children with spastic diplegic cerebral palsy is limited because of inconsistent outcomes reported in various studies and the lack of long-term evaluations. METHODS This study investigated the long-term results (mean, nine years) for fifty-three ambulatory patients with spastic diplegic cerebral palsy and stiff-knee gait treated with standardized distal rectus femoris transfer as a part of multilevel surgery. Standardized three-dimensional gait analysis and clinical examination were carried out before surgery and at one year and nine years after surgery. Patients with decreased peak knee flexion in swing phase who had distal rectus femoris transfer to correct the decreased peak knee flexion in swing phase (C-DRFT) were evaluated separately from those with normal or increased peak knee flexion in swing phase who had distal rectus femoris transfer done as a prophylactic procedure (P-DRFT). RESULTS A significantly increased peak knee flexion in swing phase was found in the C-DRFT group one year after surgery, while a significant loss (15°) in peak knee flexion in swing phase was noted in the P-DRFT group. A slight but not significant increase in peak knee flexion in swing phase in both groups was noted at the time of the long-term follow-up. A significant improvement in timing of peak knee flexion in swing phase was only found for the C-DRFT group, and was maintained after nine years. Knee motion and knee flexion velocity were significantly increased in both groups and were maintained at long-term follow-up in the C-DRFT group, while the P-DRFT showed a deterioration of knee motion. CONCLUSIONS Distal rectus femoris transfer is an effective procedure to treat stiff-knee gait featuring decreased peak knee flexion in swing phase and leads to a long-lasting increase of peak knee flexion in swing phase nine years after surgery. Patients with more involvement showed a greater potential to benefit from distal rectus femoris transfer. However, 18% of the patients showed a permanently poor response and 15% developed recurrence. In patients with severe knee flexion who underwent a prophylactic distal rectus femoris transfer, a significant loss in peak knee flexion in swing phase was noted and thus a prophylactic distal rectus femoris transfer may not be indicated in these patients. LEVEL OF EVIDENCE Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

FGF-2 addition during expansion of human bone marrow-derived stromal cells alters MSC surface marker distribution and chondrogenic differentiation potential.

Although clinical applications using mesenchymal stromal cells (MSCs) are becoming more frequent, procedures for their in vitro culture are far from standardized. Growth factors such as FGF‐2 are frequently added during expansion to improve population growth and differentiation characteristics. However, up to now its influence on surface marker distribution of MSCs has been close to unknown. The purpose of this study was therefore to analyse effects of FGF‐2 supplementation on pre‐selection of MSC subpopulations.

Efficacy of Multidisciplinary Treatment for Patients With Chronic Low Back Pain A Prospective Clinical Study in 395 Patients

BackgroundThe effectiveness of multidisciplinary treatment programs varies throughout the literature, and it remains controversial how therapy outcome is affected by patients’ individual parameters and which treatment settings work best. ObjectivesWe set out to examine the impact of patient variables on the effectiveness of a 3-week multidisciplinary treatment program in patients with chronic low back pain. By presenting effect sizes, we aimed to enable the comparison of our findings with other studies across disciplines. MethodsData on 395 patients were prospectively collected at study entry, at the end of the program (T1) and after 6 months’ follow-up (T2). Relevant therapy outcomes were analyzed by presenting effect sizes with Cohen’s d. Group comparisons were performed for sociodemographic and clinical features to determine the impact on therapy outcome. ResultsMedium effect sizes (d = −0.6 to −0.7) were shown for visual analog scale (VAS) after treatment and at T2, indicating clinically relevant pain relief. Significant changes in pain-related disability were observed immediately at T1 with a strong treatment effect (d = 0.8). Functional capacity was improved with low to medium effect sizes (0.4–0.5). Quality-of-life subscales (36-item Short Form Health Survey) improved significantly at T1 for physical function, vitality, and mental health (d = 0.5–0.8). Center for Epidemiological Studies – Depression Scale scores improved significantly with strong effect sizes of d = 0.7. Sociodemographic parameters displayed a significant impact on effect sizes for visual analog scale at T2, with females (d = −0.9), age group 30 to 39 years (d = −1), and patients with low physical job exposure (d = −0.9) benefiting most. An increase in number of pain locations (−0.7) and severity of accompanying pain (−0.7) in other body areas significantly impaired therapy outcome and effect sizes of VAS. ConclusionsThus, multidisciplinary treatment ameliorates pain, functional restoration, and quality of life with medium to high effect sizes even for patients with a long history of chronic back pain. Effect sizes are higher than for monodisciplinary treatments and treatment effects remained stable at 6-month follow-up in a longitudinal uncontrolled study design. Thus, we believe that multidisciplinary treatment is vital for the treatment of patients with chronic low back pain. The impact of sociodemographic and pain-related parameters needs to be taken into account when including patients in an appropriate treatment program. We emphasize the presentation of effect sizes as a vital treatment evaluation to enable cross-sectional comparison of therapy outcomes.

Mid- and long-term clinical results of surgical therapy in unicameral bone cysts.

BackgroundUnicameral (or simple) bone cysts (UBC) are benign tumours most often located in long bones of children and adolescents. Pathological fractures are common, and due to high recurrence rates, these lesions remain a challenge to treat. Numerous surgical procedures have been proposed, but there is no general consensus of the ideal treatment. The aim of this investigation therefore was to study the long-term outcome after surgical treatment in UBC.MethodsA retrospective analysis of 46 patients surgically treated for UBC was performed for short and mid-term outcome. Clinical and radiological outcome parameters were studied according to a modified Neer classification system. Long-term clinical information was retrieved via a questionnaire at a minimum follow-up of 10 years after surgery.ResultsForty-six patients (17 female, 29 male) with a mean age of 10.0 ± 4.8 years and with histopathologically confirmed diagnosis of UBC were included. Pathological fractures were observed in 21 cases (46%). All patients underwent surgery for UBC (35 patients underwent curettage and bone grafting as a primary therapy, 4 curettage alone, 3 received corticoid instillation and 4 decompression by cannulated screws). Overall recurrence rate after the first surgical treatment was 39% (18/46), second (17.4% of all patients) and third recurrence (4.3%) were frequently observed and were addressed by revision surgery. Recurrence was significantly higher in young and in male patients as well as in active cysts. After a mean of 52 months, 40 out of 46 cysts were considered healed. Prognosis was significantly better when recurrence was observed later than 30 months after therapy. After a mean follow-up of 15.5 ± 6.2 years, 40 patients acknowledged clinically excellent results, while five reported mild and casual pain. Only one patient reported a mild limitation of range of motion.ConclusionsOur results suggest satisfactory overall long-term outcome for the surgical treatment of UBC, although short-and mid-term observation show a considerable rate of recurrence independent of the surgical technique.