Comparison of HLA antibody identification methods for the selection of platelet products for HLA-mediated platelet refractory patients

In an ineffective transfusion context, solid-phase immunoassays using the Luminex platform for the detection and characterization of HLA antibodies are currently used to select HLA-compatible platelet products. A new HLA antibody identification method, the HISTO SPOT® HLA AB test (BAG Health care GmbH, Lich, Germany), based on the detection of antibodies directed against a recombinant single antigen (SA) by colored spots detected by HISTO MATCH HLA AB module software, runs fully automated on the MR.SPOT®. The aim of this study was to compare the ability of the HISTO SPOT HLA AB and C1qScreen™ (C1q SAB) assays with that of the Labscreen single antigen class I (OL SAB) assay to detect anti-HLA class I antibodies in 56 serum samples from 54 platelet refractory acute myeloid leukemia patients who received HLA mismatch platelet concentrates at a single oncohematology center. In total, 1414 class I specificities, 433 HLA-A and 981 HLA-B, were detected by the OL SAB test. The mean fluorescence intensity (MFI) was >5000 for 874 antigens and <5000 for 655 antigens. The HISTO SPOT® HLA AB and C1q SAB tests identified 85% and 79% of OL SA-detected antigens with an MFI >5000, respectively, but did not identify 34% and 44% of OL SAB-detected antigens, highlighting the lower sensitivity of these techniques. Interestingly, the donor-specific antibodies (DSAs) identified by the HISTO SPOT® HLA AB and C1q SAB assays reacted against HLA mismatch platelet concentrates with the same specificity (86%) and positive predictive (77%) value as in the OL SAB test when the MFI threshold was >2000 for DSA detection. Although the HISTO SPOT® HLA AB test is less sensitive than the OL SAB test, this test could be used for the selection of HLA-compatible platelet products.

Low Prevalence of HLA-G Antibodies in Lung Transplant Patients Detected using MAIPA-Adapted Protocol

Lung transplantation is often complicated by acute and/or chronic rejection leading to graft-function loss. In addition to the HLA donor-specific antibodies (HLA-DSA), a few autoantibodies are correlated with the occurrence of these complications. Recently, antibodies directed against non-classical HLA molecules, HLA-G, -E, and -F have been detected in autoimmune diseases, like systemic lupus erythematosus. Non-classical HLA molecules are crucial in the immunological acceptance of the lung graft, and some of their isoforms, like HLA-G*01:04 and -G*01:06, are associated with a negative clinical outcome. The aim of this study is to determine the frequency of detection of HLA-G antibodies in lung transplant recipients (LTRs) and their impact on the occurrence of clinical complications. After incubating the cell lines SPI-801, with and without three different HLA-G isoform expression, with sera from 90 healthy blood donors and 35 LTRs (before and after transplantation), HLA-G reactivity was revealed using reagents from commercial monoclonal antibody immobilization of platelet antigen assay (MAIPA ApDIA®). Only one serum from one blood donor had specific reactivity against the HLA-G transduced lines. Non-specific reactivity in many sera from LTRs was observed with transduced- and wild-type cell lines, which may suggest recognition of an autoantigen expressed by the SPI-801 cell line. In conclusion, this study allowed the development of a specific detection tool for non-denatured HLA-G antibodies. These antibodies seem uncommon, both in healthy subjects and in complicated LTRs. This study should be extended to patients suffering from autoimmune diseases as well as kidney and heart transplant recipients.

Early rehabilitation after reverse total shoulder prosthesis on fracture of proximal humerus in elderly patients provides better functional outcome

PURPOSE

Reverse total shoulder arthroplasty (RSA) has revolutionized the management of proximal humerus fractures (PHF) in the elderly patients. There is few or no consensus regarding to management of postoperative rehabilitation in elderly patients. An early rehabilitation from D1 allowed better functional results compared to rehabilitation started to D30 independently from tuberosities consolidation.

METHODS

94 patients operated on for PHF were evaluated retrospectively, with a minimum radio-clinical follow-up of 2 years. Clinical evaluation included mobilities and four functional scores: ASES, quick DASH, gross constant, weighted constant. Radiological evaluation was performed on a frontal shoulder X-ray with evaluation of tuberosities' consolidation.

RESULTS

The mean follow-up was 45 ± 19 months (24-88 months). Early rehabilitation was significantly associated with a better Constant Score (71.1 ± 17.2 vs. 56.4 ± 15.8; p < 0.001), better adjusted Constant score (92.4 ± 14.2 vs. 80.3 ± 19.5; p < 0.001), better quick DASH (22.8 ± 19.8 vs. 36.7 ± 21.3; p < 0.01), better ASES (78.6 ± 20.2 vs. 63 ± 22; p < 0.001).

CONCLUSION

In traumatology, functional result of RSA seems not related in tuberosities' union but in rehabilitation in order to limit postoperative stiffness of operated shoulder. An early rehabilitation is related with better clinical and functional results, independently of tuberosities' union.

LEVEL OF EVIDENCE

3, control-case study.

Evaluation of a new complement-dependent lymphocytotoxicity cross match method using an automated cell counter, the NucleoCounter® NC-3000™

Complement-dependent lymphocytotoxicity cross match (CDC-XM) is the ultimate test of donor/recipient compatibility prior to organ transplantation. This test is based on cell viability, evaluated under fluorescence microscopy by an operator after proper staining. The determination of the positivity threshold may vary depending on the operator. We developed a new method in which the final step of determining cell viability is automated using the NC-3000™ (Chemometec®), an image cytometer able to precisely determine the percentage of dead/live cells in a suspension. After T and B donor cells isolation by negative selection, complement-dependent lysis was performed in macrovolumes in a PCR plate. Then, cell viability was measured by the NC-3000™. The sensitivity and routine CDC-XM results of this new method were compared to those of CDC-XM reference method using Terasaki plates. The sensitivity of CDC-XM expressed in the ASHI scoring system of this method was similar to the reference method results for a dilution range of the positive controls. Similarly, the results of the new method were comparable in a clinical situation to those obtained with the reference method after a study of 10 cross-matches, of which 5 cross-matches with DSA were positive and five cross-matches without DSA were negative. Moreover, ASHI scores were similar to those obtained using the reference method, and the mortality percentage was reproducible (CV < 15%). The assessment of cell viability by the NC-3000™ is easy to perform and highly reproducible but requires CDC-XM to be performed by the macrovolume method. The determination of a precise percentage of viability/mortality by the automation excludes operator variability and allows a better understanding of results close to the decision threshold.

FCGR2A-HH Gene Variants Encoding the Fc Gamma Receptor for the C-Reactive Protein Are Associated with Enhanced Monocyte CD32 Expression and Cardiovascular Events’ Recurrence after Primary Acute Coronary Syndrome

Fcγ receptors (FcγRs) interact with the C-reactive protein (CRP) and mediate activation of inflammation-related pathogenic mechanisms affecting cardiovascular health. Our study evaluated whether FcγRIIA and FcγRIIIA profiles are associated with the recurrence of adverse cardiovascular events during the first year after a primary acute coronary syndrome (ACS). The primary endpoint was the recurrence of cardiovascular events (RCE), identified as a composite outcome comprising acute heart failure (AHF) and major adverse cardiovascular events (MACE). We obtained blood samples of 145 ACS patients to measure hsCRP circulating levels, to identify FcγRIIA-131RH rs1801274 and FcγRIIIA-158FV rs396991 polymorphisms, to analyze circulating monocytes and NK cell subsets expressing CD16 and CD32, and to detect serum-mediated FCGR2A-HH activation by luciferase reporter assays. The hsCRP, CD32-expression, and Fc-R mediated activation levels were similar in all patients regardless of their MACE risk. In contrast, the hsCRP levels and the proportion of CD14+ circulating monocytes expressing the CD32 receptor for CRP were significantly higher in the patients who developed AHF. The FCGR2A rs1801274 HH genotype was significantly more common in patients who developed RCE and MACE than in RCE-free patients and associated with an enhanced percentage of circulating CD32+CD14+ monocytes. The FCGR2A-HH genotype was identified as an independent predictor of subsequent RCE (OR, 2.7; p = 0.048; CI, 1.01–7.44) by multivariate analysis. These findings bring preliminary evidence that host FCGR2A genetic variants can influence monocyte CD32 receptor expression and may contribute to the fine-tuning of CD32-driven chronic activating signals that affect the risk of developing RCEs following primary ACS events.

HLA-H*02:07 Is a Membrane-Bound Ligand of Denisovan Origin That Protects against Lysis by Activated Immune Effectors

The biological relevance of genes initially categorized as “pseudogenes” is slowly emerging, notably in innate immunity. In the HLA region on chromosome 6, HLA-H is one such pseudogene; yet, it is transcribed, and its variation is associated with immune properties. Furthermore, two HLA-H alleles, H*02:07 and H*02:14, putatively encode a complete, membrane-bound HLA protein. Here we thus hypothesized that HLA-H contributes to immune homeostasis similarly to tolerogenic molecules HLA-G, -E, and -F. We tested if HLA-H*02:07 encodes a membrane-bound protein that can inhibit the cytotoxicity of effector cells. We used an HLA-null human erythroblast cell line transduced with HLA-H*02:07 cDNA to demonstrate that HLA-H*02:07 encodes a membrane-bound protein. Additionally, using a cytotoxicity assay, our results support that K562 HLA-H*02:07 inhibits human effector IL-2–activated PBMCs and human IL-2–independent NK92-MI cell line activity. Finally, through in silico genotyping of the Denisovan genome and haplotypic association with Denisovan-derived HLA-A*11, we also show that H*02:07 is of archaic origin. Hence, admixture with archaic humans brought a functional HLA-H allele into modern European and Asian populations.

Qualitative and quantitative comparison of cell-free DNA and cell-free fetal DNA isolation by four (semi-)automated extraction methods: impact in two clinical applications: chimerism quantification and noninvasive prenatal diagnosis

BACKGROUND

Non-invasive molecular analysis of cell-free DNA (cfDNA) became a sensitive biomarker for monitoring organ transplantation or for detection of fetal DNA (cffDNA) in noninvasive prenatal test. In this study, we compared the efficiencies of four (semi)-automated cfDNA isolation instruments using their respective isolation kit: MagNA Pure 24 (Roche®), IDEAL (IDSolution®), LABTurbo 24 (Taigen®) and Chemagic 360 (Perkin Elmer®). The cfDNA was isolated from 5 plasma samples and the Rhesus D (RhD)-cffDNA from 5 maternal plasmas. The cfDNA were quantified by digital droplet PCR (ddPCR), BIABooster system and QUBIT fluorometer. The cfDNA fragment size profiles were assessed by BIABooster system. Chimerism were quantified by home-made ddPCR and Devyser NGS kit. RhD-cffDNA in maternal plasma were detected between weeks 14 and 24 of amenorrhea using free DNA Fetal RHD Kit® (Biorad®).

RESULTS

Statistical tests have shown differences in DNA yield depending on the isolation procedure and quantification method used. Magna Pure isolates smaller cfDNA fragment size than other extraction methods (90% ± 9% vs. 74% ± 8%; p = 0.009). Chimerism was only reliable from LABTurbo 24 extractions using the NGS but not with ddPCR whatever extraction methods. RhD-cffDNA were detected by all isolation methods, although IDEAL and LABTurbo 24 systems seemed more efficient.

CONCLUSIONS

This comparative study showed a dependency of cfDNA yield depending on isolation procedure and quantification method used. In total, these results suggest that the choice of pre-analytical isolation systems needs to be carefully validated in routine clinical practice.

Wear debris released by hip prosthesis analysed by microcomputed tomography

Total hip arthroplasty uses commercial devices that combine different types of biomaterials. Among them, metals, ceramics and metal oxides can be used either in the prosthesis itself or in the cement used to anchor them in the bone. Over time, all of these materials can wear out and release particles that accumulate in the periprosthetic tissues or can migrate away. We used histology blocks from 15 patients (5 titanium metallosis, 5 alumina prostheses, 5 with altered methacrylic cement) to perform a microCT study and compare it with conventional histology data. An EDS-SEM analysis was done to characterise the atomic nature of the materials involved. A morphometric analysis was also performed in 3D to count the particles and assess their density and size. The metallic particles appeared to be the largest and the ceramic particles the finest. However, microCT could not reveal the wear particles of radiolucent biomaterials such as polyethylene and the very fine zirconia particles from cement fragmentation. MicroCT analysis can reveal the extent of the accumulation of these debris in the periprosthetic tissues. LAYOUT DESCRIPTION: Hip prostheses progressively degrade in the body by releasing wear debris. They accumulate in the periprosthetic tissues. Microcomputed tomography was used to image three types of radio-opaque wear debris: metal, ceramic and zirconia used in the bone cements.

Arthroscopic anatomy of the middle glenohumeral ligament. A series of 300 cases

PURPOSE

The anatomy of the middle glenohumeral ligament (MGHL) is seldomly described during arthroscopy. The aim of this study was to determine the arthroscopic variants concerning the anatomy of the MGHL.

METHODS

A prospective, observational, single-center study was conducted between June 2016 and June 2017. All patients undergoing a first-time arthroscopy of the shoulder and with no history of prior surgery or trauma of the same shoulder were consecutively enrolled. The variations of the MGHLs shape and of its glenoid and distal insertions were documented during surgery.

RESULTS

A total 300 patients were included. Surgeries included rotator cuff sutures, tenotomy/tenodesis of the long head of the biceps tendon (LHBT) and subacromial decompression in respectively 31%, 32.7% and 35.5% of cases. The MGHL was absent in 12% of cases, presented a flat structure in 72% of cases, a cord-like shape in 14% and a Buford complex was observed in 1%. Its glenoid insertion was located on the labrum between the superior (SGHL) and inferior (IGHL) in 43% of cases, presented a combined insertion with the LHBT in 7%, with the SGHL in 29% and with both the SGHL and LHBT in 9%. The distal insertion was located in 67% of cases on the subscapularis tendon (SCCT) or the capsule covering it, and on the humeral bone in 21%.

CONCLUSION

This study confirms and details the anatomic variants of the MGHL, notably describing the lesser-known variants of its distal insertion, yet arises the question of the exact nature and function of this so-called ligament.

Hyaluronic Acid Stimulates Osseointegration of β-TCP in Young and Old Ewes

Cross-linked hyaluronic acid (HyAR) increases the local concentration of growth factors. We compared β-TCP osseointegration in old and young ewes with/without HyAR addition. A blind tunnel was drilled on the medial femoral condyle of each knee in nine young and nine old ewes and was filled with β-TCP, β-TCP + HyAR or left unfilled. Double labeling with calcein allowed histodynamic analysis. Ewes were sacrificed at 84 days and the knees were harvested. MicroCT provided histomorphometric parameters: trabecular bone volume, residual volume of biomaterial. Histodynamic parameters were: mineralization rate, mineralized surfaces, bone formation rate. A non-parametric ANOVA and post hoc test analyzed differences between subgroups. Osseointegration of β-TCP was similar in the aged/young grafted groups. Trabecular bone volume was significantly increased versus ungrafted animals (p < 0.001). There were no significant difference for bone volume, residual volume of biomaterial and histodynamic parameters when a single parameter was considered but additional effects of β-TCP and HyAR were evidenced by 3D analysis. Addition of HyAR to ß-TCP does not significantly increase bone volume but tends to increase histodynamic parameters. However, considering the reduction of osteoblastic activity in aged animals, β-TCP, and HyAR boosts osteoblastic activity. HyAR leads to an equivalent response between young and old animals.

Intraosseous metal implants in orthopedics: A review

Metal implants are biomaterials widely used in orthopedics. They are both used in osteosynthesis and arthroplasty. Their mechanical properties, biocompatibility and resistance to corrosion make them a widely used option in orthopedics. Alloys are the most commonly used metals in orthopedics. As far as physical traumas are concerned, implants such as screws, plates and/or nails are used for osteosynthesis as they ensure the stability of the fractured area and contribute to bone healing. Prostheses are used in arthroplasty to restore joint function for as long as possible. Contact between bone and the prosthesis induces bone remodeling at the interface between metal and bone even if the metal is recognized as biocompatible. Upon time, the interface between the metal implant and the bony tissue is continuously modified and adapted. Hip prosthesis is a typical example of intraosseous metal implant whose bone/implant interface has been extensively studied. Metal can be altered in vivo by different mechanisms including corrosion and fretting. An altered torque friction leads to wear debris that accumulate in the peri-prosthetic tissues causing metallosis.

Soluble HLA-G Expression Inversely Correlates With Fetal Microchimerism Levels in Peripheral Blood From Women With Scleroderma

Women with scleroderma (SSc) maintain significantly higher quantities of persisting fetal microchimerism (FMc) from complete or incomplete pregnancies in their peripheral blood compared to healthy women. The non-classical class-I human leukocyte antigen (HLA) molecule HLA-G plays a pivotal role for the implantation and maintenance of pregnancy and has often been investigated in offspring from women with pregnancy complications. However data show that maternal HLA-G polymorphisms as well as maternal soluble HLA-G (sHLA-G) expression could influence pregnancy outcome. Here, we aimed to investigate the underlying role of maternal sHLA-G expression and HLA-G polymorphisms on the persistence of FMc. We measured sHLA-G levels by enzyme linked immunosorbent assay in plasma samples from 88 healthy women and 74 women with SSc. Male Mc was quantified by DYS14 real-time PCR in blood samples from 58 women who had previously given birth to at least one male child. Furthermore, eight HLA-G 5'URR/3'UTR polymorphisms, previously described as influencing HLA-G expression, were performed on DNA samples from 96 healthy women and 106 women with SSc. Peripheral sHLA-G was at lower concentration in plasma from SSc (76.2 ± 48.3 IU/mL) compared to healthy women (117.5 ± 60.1 IU/mL, p < 0.0001), independently of clinical subtypes, autoantibody profiles, disease duration, or treatments. Moreover, sHLA-G levels were inversely correlated to FMc quantities (Spearman correlation, p < 0.01). Finally, women with SSc had lower sHLA-G independently of the eight HLA-G 5'URR/3'UTR polymorphisms, although they were statistically more often homozygous than heterozygous for HLA-G polymorphism genotypes -716 (G/T), -201 (G/A), 14 bp (ins/del), and +3,142 (G/A) than healthy women. In conclusion, women with SSc display less sHLA-G expression independently of the eight HLA-G polymorphisms tested. This decreased production correlates with higher quantities of persisting FMc commonly observed in blood from SSc women. These results shed some lights on the contribution of the maternal HLA-G protein to long-term persistent fetal Mc and initiate new perspectives in this field.

Reconstruction of large diaphyseal bone defect by simplified bone transport over nail technique: A 7-case series

Reconstruction of large diaphyseal bone defect is complex and the complications rate is high. This study aimed to assess a simplified technique of segmental bone transport by monorail external fixator over an intramedullary nail.A prospective study included 7 patients: 2 femoral and 5 tibial defects. Mean age was 31years (range: 16-61years). Mean follow-up was 62 months (range: 46-84months). Defects were post-traumatic, with a mean length of 7.2cm (range: 4 to 9.5cm). For 3 patients, reconstruction followed primary failure. In 4 cases, a covering flap was necessary. Transport used an external fixator guided by an intramedullary nail, at a rate of 1mm per day. One pin was implanted on either side of the distraction zone. The external fixator was removed 1 month after bone contact at the docking site. Mean bone transport time was 11 weeks (range: 7-15 weeks). Mean external fixation time was 5.1months (range: 3.5 to 8months). Full weight-bearing was allowed 5.7months (range: 3.5-13months) after initiation of transport. In one patient, a pin had to be repositioned. In 3 patients, the transported segment re-ascended after external fixatorablation, requiring repeat external fixation and resumption of transport. There was just 1 case of superficial pin infection. Reconstruction quality was considered "excellent" on the Paley-Marr criteria in 6 cases. The present technique provided excellent reconstruction quality in 6 of the 7 cases. External fixation time was shorter and resumption of weight-bearing earlier than with other reconstruction techniques, notably including bone autograft, vascularized bone graft or the induced membrane technique. Nailing facilitated control of limb axis and length. The complications rate was 50%, comparable to other techniques. This study raises the question of systematic internal fixation of the docking site, to avoid any mobilization of the transported segment. The bone quality, axial control and rapidity shown by the present technique make it well-adapted to reconstruction of diaphyseal bone defect.

LEVEL OF EVIDENCE

Four-case series.

Percutaneous reduction of proximal radius fracture in adults. A 12-case series

Fractures of the head or neck of the radius account for 5% of elbow fractures in adults. Treatment varies between authors. We report a retrospective series of 12 cases of percutaneous reduction of Mason II radial head fracture, without internal fixation. All fractures consolidated, without secondary displacement. There were no postoperative complications. Mean ranges of motion were 136° flexion-extension and 175° pronation-supination. Mean QuickDASH score was 11. Results in the present series were at least comparable to those for other techniques, validating percutaneous treatment as a solution for radial head fracture.

TYPE OF STUDY

Case series.

LEVEL OF EVIDENCE

IV.

Soluble CD146 boosts therapeutic effect of endothelial progenitors through proteolytic processing of short CD146 isoform

AIMS

Endothelial colony-forming cells (ECFC) constitute an endothelial progenitor fraction with a promising interest for the treatment of ischaemic cardiovascular diseases. As soluble CD146 (sCD146) is a new factor promoting angiogenesis, we examined whether sCD146 priming could improve the therapeutic potential of ECFC and defined the involved mechanism.

METHODS AND RESULTS

We investigated the effects of sCD146 priming on regenerative properties of ECFC in vivo. In a mouse model of hindlimb ischaemia, the homing of radiolabelled cells to ischaemic tissue was assessed by SPECT-CT imaging. Soluble CD146 priming did not modify the number of engrafted ECFC but improved their survival capacity, leading to an enhanced revascularization. The mechanism of action of sCD146 on ECFC was studied in vitro. We showed that sCD146 acts in ECFC through a signalosome, located in lipid rafts, containing angiomotin, the short isoform of CD146 (shCD146), VEGFR1, VEGFR2, and presenilin-1. Soluble CD146 induced a sequential proteolytic cleavage of shCD146, with an extracellular shedding followed by an intramembrane cleavage mediated by matrix metalloprotease (MMP)/ADAM and presenilin-1, respectively. The generated intracellular part of shCD146 was directed towards the nucleus where it associated with the transcription factor CSL and modulated the transcription of genes involved in cell survival (FADD, Bcl-xl) and angiogenesis (eNOS). This effect was dependent on both VEGFR1 and VEGFR2, which were rapidly phosphorylated by sCD146.

CONCLUSIONS

These findings establish that activation of the proteolytic processing of shCD146, in particular by sCD146, constitutes a promising pathway to improve endothelial progenitors' regenerative properties for the treatment of cardiovascular diseases.

Aluminum and bone: Review of new clinical circumstances associated with Al(3+) deposition in the calcified matrix of bone

Several decades ago, aluminum encephalopathy associated with osteomalacia has been recognized as the major complication of chronic renal failure in dialyzed patients. Removal of aluminum from the dialysate has led to a disappearance of the disease. However, aluminum deposit occurs in the hydroxyapatite of the bone matrix in some clinical circumstances that are presented in this review. We have encountered aluminum in bone in patients with an increased intestinal permeability (coeliac disease), or in the case of prolonged administration of aluminum anti-acid drugs. A colocalisation of aluminum with iron was also noted in cases of hemochromatosis and sickle cell anemia. Aluminium was also identified in a series of patients with exostosis, a frequent benign bone tumor. Corrosion of prosthetic implants composed of grade V titanium (TA6V is an alloy containing 6% aluminum and 4% vanadium) was also observed in a series of hip or knee revisions. Aluminum can be identified in undecalcified bone matrix stained by solochrome azurine, a highly specific stain allowing the detection of 0.03 atomic %. Colocalization of aluminum and iron does not seem to be the fruit of chance but the cellular and molecular mechanisms are still poorly understood. Histochemistry is superior to spectroscopic analyses (EDS and WDS in scanning electron microscopy).

Two new cases of serine deficiency disorders treated with l-serine

OBJECTIVE AND PATIENTS

We report on two new cases of serine deficiency due respectively to 3-phosphoglycerate dehydrogenase (PHGDH) deficiency (Patient 1) and phosphoserine aminotransferase (PSAT1) deficiency (Patient 2), presenting with congenital microcephaly (<3rd centile at birth) and encephalopathy with spasticity. Patient 1 had also intractable seizures. A treatment with oral l-serine was started at age 4.5 years and 3 months respectively.

RESULTS

Serine levels were low in plasma and CSF relative to the reference population, for which we confirm recently redefined intervals based on a larger number of samples. l-Serine treatment led in patient 1 to a significant reduction of seizures after one week of treatment and decrease of electroencephalographic abnormalities within one year. In patient 2 treatment with l-serine led to an improvement of spasticity. However for both patients, l-serine failed to improve substantially head circumference (HC) and neurocognitive development. In a couple related to patient's 2 family, dosage of serine was performed on fetal cord blood when the fetus presented severe microcephaly, showing reduced serine levels at 30 weeks of pregnancy.

CONCLUSIONS

l-Serine treatment in patients with 2 different serine synthesis defects, led to a significant reduction of seizures and an improvement of spasticity, but failed to improve substantially neurocognitive impairment. Therefore, CSF and plasma serine levels should be measured in all cases of severe microcephaly at birth to screen for serine deficiency, as prompt treatment with l-serine may significantly impact the outcome of the disease. Reduced serine levels in fetal cord blood may also be diagnostic as early as 30 weeks of pregnancy.

Predictive factors of scapular notching in patients with reverse shoulder arthroplasty

INTRODUCTION

The main complication of reverse shoulder arthroplasty is the development of notches in the scapular pillar, which occurs in 44% to 100% of cases. Furthermore the functional score has been shown to be poorer in patients with high-grade notches. Many options have been proposed to reduce this risk. The purpose of this study was to evaluate the predictive factors of the development of scapular notches.

MATERIALS AND METHODS

We retrospectively evaluated 133 shoulders in 121 patients with reverse shoulder arthroplasty. We performed a radiographic assessment of the effect of positioning the glenoid component with inferior overhang of the glenosphere and the glenometaphyseal angle. All patients were reviewed after 2years follow-up, including a clinical assessment based on the Constant score and X-rays to assess the presence of notches.

RESULTS

Nineteen complications were reported, and 14 required revision surgery. We excluded patients in whom prosthetic components were changed. The quality of the X-rays was not satisfactory enough to be analyzed in over 15 patients so they were excluded. One hundred five patients were reviewed. At 2years follow-up, 50.4% of shoulders presented with notches. The Constant score was 69.3 points (54-83) in shoulders without notches, and 66.4 points (38-82) in shoulders with notches. The average glenosphere overhang was 3.5mm (-1 - 8mm). Notches were present in 65.5% if it was less than 3mm and 39.6% if it was more than 2mm (P<0. 05). The average glenometaphyseal angle was 27.3° (4-59°), and notches developed in 72.2% if it was more than 28° and 26.5% if it was less than 28° (P<0.05).

CONCLUSION

The position of the metaglene influences the development of notches. The risk decreases if the glenosphere overhangs the glenoid. The degree of adduction of the arm influences the development of notches and can be correlated with the patient's BMI.

LEVEL OF EVIDENCE

Level IV retrospective study.

Neutrophils recruit and activate human endothelial colony-forming cells at the site of vessel injury via P-selectin glycoprotein ligand-1 and L-selectin

BACKGROUND

Endothelial colony-forming cells (ECFCs) represent a subpopulation of circulating endothelial progenitor cells that have been implicated in vascular repair. However, no study has evaluated the role of ECFCs in endothelial injury leading to thrombus formation.

OBJECTIVE

We investigated the kinetics, mechanisms and role of ECFC recruitment in the dynamics of thrombus formation and stabilization.

METHODS AND RESULTS

Using digital intravital microscopy in living mice, we show that ECFCs, but not mature endothelial cells, adhere to sites of laser-induced injury and do not affect the kinetics of thrombus formation. This interaction occurs once the platelet thrombus has been stabilized, and is dependent on the presence of neutrophils but not platelets or fibrin. In vitro, the interaction of the activated neutrophils with activated endothelial cells is a prerequisite for the capture of ECFCs. Neutrophils activate ECFCs and increase their angiogenic properties, such as their ability to migrate and to form pseudocapillaries. This newly identified interaction of ECFCs with the neutrophils is mediated by the P-selectin glycoprotein ligand-1 (PSGL-1)/L-selectin axis both in vitro and in vivo.

CONCLUSIONS

This study is the first demonstration that neutrophils present at the site of injury recruit ECFCs via PSGL-1/L-selectin. This interaction between neutrophils and ECFCs could play a key role in the regeneration of injured vessels in pathophysiologic conditions.

Sphingosine kinase 1 expressed by endothelial colony-forming cells has a critical role in their revascularization activity

AIMS

Cell therapy based on endothelial colony-forming cells (ECFCs) is a promising option for ischaemic cardiovascular diseases. A better understanding of the mechanisms by which these cells promote revascularization remains a critical challenge to improving their therapeutic potential. We aimed to identify the critical mechanisms involved in the revascularization activity of ECFCs by using the paracrine properties of mesenchymal stem cells (MSC).

METHODS AND RESULTS

Conditioned medium from human bone marrow-derived MSCs (MSC-CM) increased the angiogenic activity of cord blood ECFCs in vitro (proliferation, migration, and pseudo-tube formation), the survival of ECFCs in mice (Matrigel Plug assay), and the capacity of ECFCs to promote the recovery of blood perfusion in mice with hindlimb ischaemia. Furthermore, the capillary density in ischaemic gastrocnemius muscle was significantly increased in mice transplanted with the ECFCs pre-treated with the MSC-CM. The enhancement of ECFCs activity involved the up-regulation of sphingosine kinase 1 (SphK1) expression and activity. The inhibition of SphK1 in ECFCs by using an inhibitor or a siRNA knockdown of SphK1 prevented the stimulation of the ECFCs induced by the MSC-CM. The improvement of ECFC activity by MSC-CM also involved the up-regulation of sphingosine-1-phosphate receptor 1 (S1P1) and a S1P/S1P1/3-dependent mechanism. Finally, we showed that the stimulation of ECFCs with exogenous S1P increased angiogenesis and promoted blood perfusion in hindlimb ischaemia.

CONCLUSION

The up-regulation of SphK1 and S1P-dependent pathways is critical for the angiogenic/vasculogenic activity of ECFCs. The identification of this pathway provides attractive targets to optimize cell-based therapy for revascularization in ischaemic diseases.

Soluble melanoma cell adhesion molecule (sMCAM/sCD146) promotes angiogenic effects on endothelial progenitor cells through angiomotin

The melanoma cell adhesion molecule (CD146) contains a circulating proteolytic variant (sCD146), which is involved in inflammation and angiogenesis. Its circulating level is modulated in different pathologies, but its intracellular transduction pathways are still largely unknown. Using peptide pulldown and mass spectrometry, we identified angiomotin as a sCD146-associated protein in endothelial progenitor cells (EPC). Interaction between angiomotin and sCD146 was confirmed by enzyme-linked immunosorbent assay (ELISA), homogeneous time-resolved fluorescence, and binding of sCD146 on both immobilized recombinant angiomotin and angiomotin-transfected cells. Silencing angiomotin in EPC inhibited sCD146 angiogenic effects, i.e. EPC migration, proliferation, and capacity to form capillary-like structures in Matrigel. In addition, sCD146 effects were inhibited by the angiomotin inhibitor angiostatin and competition with recombinant angiomotin. Finally, binding of sCD146 on angiomotin triggered the activation of several transduction pathways that were identified by antibody array. These results delineate a novel signaling pathway where sCD146 binds to angiomotin to stimulate a proangiogenic response. This result is important to find novel target cells of sCD146 and for the development of therapeutic strategies based on EPC in the treatment of ischemic diseases.

Management of the stiff shoulder. A prospective multicenter comparative study of the six main techniques in use: 235 cases

INTRODUCTION

Stiffness in the shoulder is a frequent symptom associated with a number of clinical entities whose management remains inadequately defined.

PATIENTS AND METHODS

This prospective study of 235 cases of stiffness in the shoulder compared six therapeutic techniques with a mean follow-up of 13 months (range, 3-28 months) (T1: 58 cases, conventional rehabilitation under the pain threshold, T2: 59 cases, self-rehabilitation over the pain threshold, T3: 31 cases, T2 + supervision, T4: 11 cases, T1 + capsular distension, T5: 31 cases, T1 + locoregional anesthesia, T6: 45 cases, T1 + T5 + capsulotomy). The therapeutic power of each technique and its impact on the result were assessed at each self-rehabilitation and rehabilitation session during the first 6 weeks and then at 3 months, 6 months, and at the final revision depending on subjective criteria (pain, discomfort, and morale) and objective criteria (Constant score, goniometric measurements).

RESULTS

Conventional rehabilitation (T1) is less effective than self-rehabilitation over the pain threshold (T2 & T3) during the first 6 weeks (P<0.05). Self-rehabilitation stagnates between the 6th and 12th week except when it is supervised by a therapist (T3). Anesthesia (T4) and capsular distension (T5) do not lead to significantly different progression beyond 6 months. Capsulotomy does not demonstrate greater therapeutic power but its failure rate (persisting stiffness at 1 year) is 0% versus 14-17% for the other techniques (P<0.05).

DISCUSSION

The techniques are complementary and therapeutic success stems from an algorithm adapted to the individual patient with, over the first 3 months, successive self-rehabilitation and conventional rehabilitation, possibly completed by capsular distension or anesthesia between the 3rd and 6th months. In case of failure at 6 months, endoscopic capsulotomy can be proposed. Therapeutic patient education and active participation are the key to treatment success or failure.

Kinetic analyses guide the therapeutic decision in a novel form of moderate aromatic Acid decarboxylase deficiency

BACKGROUND

Aromatic amino acid decarboxylase (AADC) deficiency is a rare autosomal recessive disorder resulting in a combined dopamine and serotonin deficiency. About 50% of the cases set in the neonatal period. Here, we report an atypical clinical presentation with moderate symptoms.

PATIENT

At 10months old, the patient presented paroxysmal eye movements without seizures, and feeding difficulties which were attributed to gastroesophageal reflux. She was investigated at the age of 7years, because of orofacial dyspraxia, hypomimie, axial hypotonia and focal segmental dystonia, bilateral ptosis, without evidence for cognitive impairment.

RESULTS

HVA [110nM; (reference value (rv): 202-596)] and HIAA (12nM; rv: 87-366) decreased, OMD (520nM; rv: 5-60) and 5-HTP (56nM; rv: 2-16) increased in CSF. We confirmed the diagnosis of AADC deficiency because the activity in plasma was low: 4pmol/min/ml; rv: 16-137. The kinetic analysis revealed a sixfold increase in the apparent affinity for L-dopa (4.26mM; control=0.71), but the V (max) was unchanged (37.5pmol dopamine/min/ml; control=39.1), suggesting a modification in the substrate binding-site. Molecular analysis revealed two heterozygous mutations in the DDC gene: c1040G > A; pR347Q already described, and a novel mutation c478C > T, pR160W.

CONCLUSION

(1) CSF neurotransmitters metabolites suggested a moderate AADC deficiency; (2) The initial velocity saturation curve for L-dopa displayed a cooperative ligand binding behavior, in keeping with the modifications of the three-dimensional structure, induced by the amino acid substitutions (3) The treatment combination of L-dopa with pyridoxine dramatically improved the quality of life, the fatigability, and the paroxysmal eye movements.

Isolated interfragmentary compression for nonunion of humeral shaft fractures initially treated by nailing: A preliminary report of seven cases

INTRODUCTION

Plating with bone grafting is considered the gold standard treatment for nonunion of humeral shaft fractures. However, this complex procedure involves multiple risks. The aim of this study is to evaluate an alternative treatment using isolated axial interfragmentary compression for the dynamisation of humeral shaft nonunion after retrograde locked nailing.

MATERIALS AND METHODS

Between January 2000 and May 2009, 124 humeral shaft fractures were treated in our trauma department with retrograde locked nailing using the unreamed humeral nail (UHN(®), Synthes, Paoli, PA, USA). Nonunion occurred in seven patients (5.6%) - five females and two males, mean age 44 years (range: 17-73 years). The nonunion was treated by applying isolated secondary interfragmentary compression. Mean follow-up was 43 months (range: 8-74 months). The Rommens score and the disabilities of the arm, shoulder and hand (DASH) score were used to evaluate the global functioning of the upper limb.

RESULTS

The compression procedure was successful in all seven cases. In each case, the union occurred without any complications in 3-5 months. The mean DASH score was 25/100 (range: 8.3-60.8/100). The Rommens score was judged excellent for five of the seven patients but two were rated moderate. One of these suffered from complex regional pain syndrome type II since the fracture, and another developed a stiff shoulder 6 months after trauma.

CONCLUSION

Isolated secondary interfragmentary compression appears to be a simple and successful procedure in cases of humeral nonunion.

[Treatment of 2 cases of kerions with griseofulvin and oral steroids]

We report on 2 cases of kerions in children: one of them was located on the pubis, an exceptional location; the second one was located on the scalp and presented like multiple abscess of the scalp, for which surgical drainage was performed. In both cases, Trichophyton mentagrophytes was involved. This dermatophyte is zoophilic, contrary to the dermatophytes usually involved in tinea capitis, which could explain the poor adaptation of the dermatophyte to the human host, who would therefore react by generating a severe inflammatory reaction. Antifungal drugs are recommended for the treatment of kerions, especially griseofuline for 6 to 8 weeks. The value of oral steroids and surgery continues to be debated.

Multiple OXPHOS deficiency in the liver of a patient with CblA methylmalonic aciduria sensitive to vitamin B(12)

An adult patient with methylmalonic aciduria due to defective cobalamin synthesis (CblA) responsive to vitamin B(12) presented suddenly with severe visual impairment ascribed to optic atrophy followed by a fatal multiorgan failure and lactic acidosis but low methylmalonic acid in plasma and urine. Multiple deficiency of oxidative phosphorylation was found in the patient's liver. We suggest that patients with B(12)-sensitive methylmalonic aciduria who have a milder clinical course should be carefully monitored for long-term complications.

A prospective study of a new locking plate for proximal humeral fracture

Displaced and unstable extra-articular fractures of the proximal humerus are treated by operative reduction and fixation using various techniques such as fixed plates and intramedullary implants. This prospective study evaluates the clinical efficacy of a novel implant that is attached to the humeral head with fixed-angle locking screws. Between October 2002 and November 2005, 99 people (mean age 62.8 years) with proximal humeral fractures received treatment involving this plate in our department. The mean follow-up time was 17.8 months. Outcome was assessed with radiography, the Constant-Murley (C-M) shoulder evaluation and the Disabilities of the Arm, Shoulder and Hand (DASH) score. The mean C-M score was 64.95% and the mean DASH score was 30.1 points. Outcome was judged excellent in 51%, good in 19%, moderate in 19% and poor in 11% of cases.

Chromosome 11p15 paternal isodisomy in focal forms of neonatal hyperinsulinism

CONTEXT

Focal forms of congenital hyperinsulinism are due to a constitutional heterozygous mutation of paternal origin in the ABCC8 gene, more often than the KCNJ11 gene, located in the 11p15.1 region. This mutation is associated with the loss of the maternally inherited 11p15.1 to 11p15.5 region in the lesion. We investigated the possible occurrence of a compensatory duplication of the paternal 11p15.1-11p15.5 region.

MATERIALS AND METHODS

A combined immunohistochemistry and fluorescent in situ hybridization study on beta-cell interphase nuclei with probes covering two genes located in this region (ABCC8 and CDKN1C genes) was performed in four cases of focal forms of hyperinsulinism.

RESULTS

beta-Cells in the lesions of four cases of focal congenital hyperinsulinism were diploid for chromosomes 11 and 13. The 11p15.1 to 11p15.2 and 11p15.4 to 11p15.5 regions containing ABCC8 and CDKN1C genes, respectively, were present with two copies. Loss of the maternal allele was confirmed in these focal lesions with microsatellite markers flanking the ABCC8 and CDKN1C genes, whereas a heterozygous mutation in the ABCC8 gene was inherited from the father.

CONCLUSIONS

There is a duplication of the paternal allele on chromosome 11 in the focal forms of hyperinsulinism lesion. The paternal isodisomy observed rendered the beta-cells homozygous for ABCC8 mutation and harbored a K-channel defect in the lesion similar to that observed in diffuse forms of congenital hyperinsulinism.

Osteopontin is histochemically detected by the AgNOR acid-silver staining

Silver nitrate staining of decalcified bone sections is known to reveal osteocyte canaliculi and cement lines. Nucleolar Organising Regions (NOR) are part of the nucleolus, containing argyrophilic proteins (nucleoclin/C23, nucleophosmin/B23) that can be identified by silver staining at low pH. The aim of this study was to clarify the mechanism explaining why AgNOR staining also reveals osteocyte canaliculi. Human bone and kidney sections were processed for silver staining at light and electron microscopy with a modified method used to identify AgNOR. Sections were processed in parallel for immunohistochemistry with an antibody direct against osteopontin. Protein extraction was done in the renal cortex and decalcified bone and the proteins were separated by western blotting. Purified hOPN was also used as a control. Proteins were electro-transferred on polyvinylidene difluoride membranes and stained for AgNOR proteins. In bone, Ag staining identified AgNOR in cell nuclei, as well as in osteocyte canaliculi, cement and resting lines. In the distal convoluted tubules of the kidney, silver deposits were also observed in cytoplasmic granules on the apical side of the cells. Immunolocalization of osteopontin closely matched with all these locations in bone and kidney. Ag staining of membranes at low pH revealed bands for NOR proteins and 56 KDa (kidney), 60KDa (purified hOPN) and 75 KDa (bone) bands that corresponded to osteopontin. NOR proteins and osteopontin are proteins containing aspartic acid rich regions that can bind Ag. Staining protocols using silver nitrate at low pH can identify these proteins on histological sections or membranes.

Reverse shoulder arthroplasty for the treatment of three- and four-part fractures of the proximal humerus in the elderly: a prospective review of 43 cases with a short-term follow-up

We used an inverted shoulder arthroplasty in 43 consecutive patients with a mean age of 78 years (65 to 97) who had sustained a three- or four-part fracture of the upper humerus. All except two were reviewed with a mean follow-up of 22 months (6 to 58). The clinical outcome was satisfactory with a mean active anterior elevation of 97 degrees (35 degrees to 160 degrees ) and a mean active external rotation in abduction of 30 degrees (0 degrees to 80 degrees ). The mean Constant and the mean modified Constant scores were respectively 44 (16 to 69) and 66% (25% to 97%). Complications included three patients with reflex sympathetic dystrophy, five with neurological complications, most of which resolved, and one with an anterior dislocation. Radiography showed peri-prosthetic calcification in 36 patients (90%), displacement of the tuberosities in 19 (53%) and a scapular notch in ten (25%). Compared with conventional hemiarthroplasty, satisfactory mobility was obtained despite frequent migration of the tuberosities. However, long-term results are required before reverse shoulder arthroplasty can be recommended as a routine procedure in complex fractures of the upper humerus in the elderly.

[Retrograde locked nailing of humeral shaft fractures: a prospective study of 58 cases]

PURPOSE OF THE STUDY

Appropriate treatment for humeral shaft fractures remains a debated issue. Among the classical osteosynthesis techniques proposed, closed nailing was adapted to the humerus rather late, using the anterograde method. Use of retrograde nailing, which spares the rotator cuff, is more recent. The purpose of this study was to report outcome in 58 humeral shaft fractures in adults treated using the universal humeral nail between January 2000 and December 2003.

MATERIAL AND METHODS

This work was limited to recent shaft fractures in adults with non-pathological bones. The fractures included were all situated between the insertion of the pectoralis major and a point situated 2 cm above the apex of the olecraneum fossa. The series included 58 patients with 58 humeral shaft fractures. All fractures were closed except four (Gustilo type I and II). Two patients presented preoperative radial paralysis which was not considered to be a contraindication for retrograde locking nailing. The paralysis recovered in both patients, after neurolysis performed during the nailing procedure in one. Osteosynthesis was performed without opening the fracture focus under fluoroscopic control using a static locking nail inserted retrograde in patients in the supine position.

RESULTS

There were two early deaths unrelated to the method. Healing was obtained in the surviving patients within fifteen weeks on average. Bone healing was primary in 53 patients and after secondary compression in three. At last follow-up, shoulder motion was normal in 88% of patients and elbow motion in 91%. The Rommens functional score was good in 84%. Complications included three cases of spontaneously regressive postoperative radial paralysis, three cases of reflex dystrophy including two which regressed, and two cases of humeral palette fracture requiring surgical osteosynthesis. The proximal screws were removed in six patients because of pain or migration. To date, implants have been removed in three patients without problem. There were no infections.

CONCLUSION

Retrograde insertion of this nail facilitates treatment of humeral shaft fractures by allowing immediate joint motion and the advantages of closed reduction: no infection, no late bone healing requiring conversion to another method of fixation. The residual technical problems concern proximal nailing and nail introduction.

Molar tooth sign and superior vermian dysplasia: a radiological, clinical, and genetic study

We have identified a group of 13 patients with a homogeneous radiological pattern at MRI consisting of the molar tooth sign (MTS) and superior vermian dysplasia. The patients represent a relatively heterogeneous clinical group with variable severity of developmental delay, ataxia, hypotonia, and apnea. Careful examination of MRI prompted us to split our series of patients into two groups, based on IVth ventricle dilatation. In 4/13 patients the IVth ventricle was judged to be dilated and those patients were less severely affected while most clinically affected patients had a normal IVth ventricle. DNA samples of blood leukocytes from 6/13 consanguineous patients were genotyped using polymorphic markers encompassing the Joubert syndrome loci. We therefore sequenced AHI1 located in 6q23 in two patients who were homozygous at the locus and in four sporadic cases. Only one homozygous nonsense mutation was identified. Clinically, the patient exhibiting the AHI1 mutation was the most severely affected child with a profound encephalopathy, major hypotonia, ataxia, Leber congenital amaurosis, and normal IVth ventricle at the MRI. The present study suggests that the syndrome associating MTS and dysplasia of the superior vermis of the cerebellum is a clinically and genetically heterogeneous entity and that Jouberin (AHI1) mutations account for a marginal fraction of patients.

Congenital hyperinsulinism and mosaic abnormalities of the ploidy

BACKGROUND

Congenital hyperinsulinism and Beckwith-Wiedemann syndrome both lead to beta islet hyperplasia and neonatal hypoglycaemia. They may be related to complex genetic/epigenetic abnormalities of the imprinted 11p15 region. The possibility of common pathophysiological determinants has not been thoroughly investigated.

OBJECTIVE

To report abnormalities of the ploidy in two unrelated patients with congenital hyperinsulinism.

METHODS

Two patients with severe congenital hyperinsulinism, one overlapping with Beckwith-Wiedemann syndrome, had pancreatic histology, ex vivo potassium channel electrophysiological studies, and mutation detection of the encoding genes. The parental genetic contribution was explored using genome-wide polymorphism, fluorescent in situ hybridisation (FISH), and blood group typing studies.

RESULTS

Histological findings diverged from those described in focal congenital hyperinsulinism or Beckwith-Wiedemann syndrome. No potassium channel dysfunction and no mutation of its encoding genes (SUR1, KIR6.2) were detected. In patient 1 with congenital hyperinsulinism and Beckwith-Wiedemann syndrome, paternal isodisomy for the whole haploid set was homogeneous in the pancreatic lesion, and mosaic in the leucocytes and skin fibroblasts (hemihypertrophic segment). Blood group typing confirmed the presence of two erythroid populations (bi-parental v paternal only contribution). Patient 2 had two pancreatic lesions, both revealing triploidy with paternal heterodisomy. Karyotype and FISH analyses done on the fibroblasts and leucocytes of both patients were unremarkable (diploidy).

CONCLUSIONS

Diploid (biparental/paternal-only) mosaicism and diploid/triploid mosaicism were present in two distinct patients with congenital hyperinsulinism. These chromosomal abnormalities led to paternal disomy for the whole haploid set in pancreatic lesions (with isodisomy or heterodisomy), thereby extending the range and complexity of the mechanisms underlying congenital hyperinsulinism, associated or not with Beckwith-Wiedemann syndrome.

Le lambeau de serratus anterior en chirurgie reconstructrice du membre inférieur. À propos de 30 cas

Between 2001 and 2003, 30 serratus anterior free flaps have been realized in our unit for reconstruction of lower limb. The flaps were indicated for repair of traumatic soft tissue defect in 19 cases, for chronic wound in six cases, for purpura fulminans in two cases, for pressure sore in one case and after tumor resection in 1 case. There were 29 patients: 25 males and four females. They ranged in age from 5 to 64 years. The size of the soft tissue defects ranged between 15 and 180 cm(2). Four different types of serratus anterior flaps were used: 20 muscle flaps ; four myocutaneous flaps ; five costo-osteomuscular flap ; one costo-osteomyocutaneous flap . In all cases we used osteo flap (8 th rib) in order to restore bone defect, which ranged from 9 to 15 cm. Necrosis occurred in two flaps because of venous thrombosis. The functional outcome was good for all patients and the aesthetic sequelae at the donor site were considered as minor. The serratus anterior flap can be used in many different ways: different kinds of flaps (osteo-cutaneous-muscle); very variable size of flap (15 to 180 cm(2) in our series) , different length of pedicle possible. Because of his versatility and his absence of major functional or aesthetic sequelae the serratus anterior free flap has become day by day our favourite option in limb reconstruction.

Bisphenol a binds to the low-affinity estrogen binding site

Environmental estrogens are suspected of being involved in the current increase in the incidence of human reproductive malfunctions, such as a decrease in male reproductive capacity and an increased incidence of breast cancer in women. The influences of these compounds have been proposed to be mediated through binding to macromolecules, such as estrogen receptor alpha or beta. In this study we examined whether the low-affinity Type II estrogen binding site (Type II EBS), originally identified in the rat uterus, is a possible mediator of environmental estrogens such as bisphenol A (BPA). Analysis of BPA's binding to an enriched fraction of Type II EBS, using a competition assay, indicated that BPA was able to compete with estradiol in binding to this site. At a concentration of 10-15 microM (comparable to that required to induce uterine proliferation), BPA inhibited the binding of estradiol to Type II EBS by greater than 50%. The binding affinity of BPA for the Type II EBS was only 8-10-fold lower than that of the synthetic estrogen diethylstilbestrol. The binding of BPA to Type II EBS appeared specific to BPA, in that endosulfan, another environmental estrogen, failed to displace estradiol from the site. A comparison of the relative binding affinities of BPA for rat uterine estrogen receptor alpha to that of the Type II EBS implies that BPA preferentially binds to the Type II EBS.

Modelling dissimilarity: generalizing ultrametric and additive tree representations

Methods for the hierarchical clustering of an object set produce a sequence of nested partitions such that object classes within each successive partition are constructed from the union of object classes present at the previous level. Any such sequence of nested partitions can in turn be characterized by an ultrametric. An approach to generalizing an (ultrametric) representation is proposed in which the nested character of the partition sequence is relaxed and replaced by the weaker requirement that the classes within each partition contain objects consecutive with respect to a fixed ordering of the objects. A method for fitting such a structure to a given proximity matrix is discussed, along with several alternative strategies for graphical representation. Using this same ultrametric extension, additive tree representations can also be generalized by replacing the ultrametric component in the decomposition of an additive tree (into an ultrametric and a centroid metric). A common numerical illustration is developed and maintained throughout the paper.

The effect of alpha-lactalbumin and beta-lactoglobulin hydrolysates on the metabolic activity of Escherichia coli JM103

Bovine milk proteins alpha-lactalbumin (alpha-la) and beta-lactoglobulin (beta-lg) were hydrolysed with seven different proteolytic enzymes, and the effect of various hydrolysates on a genetically modified luminous Escherichia coli JM103 was tested in vitro with a bioluminescence assay for bacterial growth and metabolism. Undigested proteins did not inhibit the activity of tested E. coli JM103 at a concentration as high as 0.1 g ml-1. At the same concentrations, alpha-la hydrolysed with pepsin or trypsin and beta-lg hydrolysed with alcalase, pepsin or trypsin, showed a lower metabolic activity during the first 8 h of growth. The activity of E. coli JM103 in the presence of 25 mg ml-1 alpha-la or beta-lg hydrolysed with pepsin and trypsin was only 21% of the control after incubation for 6 h. The preliminary results indicated that ultrafiltration through 10 kDa and 1 kDa molecular mass cut-off membranes may be used to enrich bacteriostatic properties.

Does venous microemboli detection add to the interpretation of D-dimer values following orthopedic surgery?

The identification of risk factors for deep venous thrombosis (DVT) following orthopedic surgery remains unclear. We have investigated the relationship between plasma levels of D-dimer (DD), the presence or absence of microemboli 1 day after surgery, and the occurrence of DVT 7 days after total hip or knee replacement. The prevalence of DVT was 25 (13.3%) among 188 patients and was lower in 112 patients with DD < 2808 ng mL(-1) than in the 56 patients with higher DD levels: respectively, 8.0% vs. 21.4% (p < 0.05). D-dimer is not suitable for individual estimation of DVT risk. Microemboli were found in 112 (60%) of 186 subjects. The presence/absence or the frequency of the microemboli showed no relationship with the occurrence of DVT. Last, when evaluating the risk of DVT in orthopedic surgery, microemboli detection does not add to the interpretation of DD concentration.

Heritability of nociception II. 'Types' of nociception revealed by genetic correlation analysis

Clinical pain syndromes, and experimental assays of nociception, are differentially affected by manipulations such as drug administration and exposure to environmental stress. This suggests that there are different 'types' of pain. We exploited genetic differences among inbred strains of mice in an attempt to define these primary 'types'; that is, to identify the fundamental parameters of pain processing. Eleven randomly-chosen inbred mouse strains were tested for their basal sensitivity on 12 common measures of nociception. These measures provided for a range of different nociceptive dimensions including noxious stimulus modality, location, duration and etiology, among others. Since individual members of inbred strains are identical at all genetic loci, the observation of correlated strain means in any given pair of nociceptive assays is an index of genetic correlation between these assays, and hence an indication of common physiological mediation. Obtained correlation matrices were subjected to multivariate analyses to identify constellations of nociceptive assays with common genetic mediation. This analysis revealed three major clusters of nociception: (1) baseline thermal nociception, (2) spontaneously-emitted responses to chemical stimuli, and (3) baseline mechanical sensitivity and cutaneous hypersensitivity. Many other nociceptive parameters that might a priori have been considered closely related proved to be genetically divergent.

Heritability of nociception I: responses of 11 inbred mouse strains on 12 measures of nociception

It is generally acknowledged that humans display highly variable sensitivity to pain, including variable responses to identical injuries or pathologies. The possible contribution of genetic factors has, however, been largely overlooked. An emerging rodent literature documents the importance of genotype in mediating basal nociceptive sensitivity, in establishing a predisposition to neuropathic pain following neural injury, and in determining sensitivity to pharmacological agents and endogenous antinociception. One clear finding from these studies is that the effect of genotype is at least partially specific to the nociceptive assay being considered. In this report we begin to systematically describe and characterize genetic variability of nociception in a mammalian species, Mus musculus. We tested 11 readily-available inbred mouse strains (129/J, A/J, AKR/J, BALB/cJ, C3H/HeJ, C57BL/6J, C58/J, CBA/J, DBA/2J, RIIIS/J and SM/J) using 12 common measures of nociception. These included assays for thermal nociception (hot plate, Hargreaves' test, tail withdrawal), mechanical nociception (von Frey filaments), chemical nociception (abdominal constriction, carrageenan, formalin), and neuropathic pain (autotomy, Chung model peripheral nerve injury). We demonstrate the existence of clear strain differences in each assay, with 1.2 to 54-fold ranges of sensitivity. All nociceptive assays display moderate-to-high heritability (h2 = 0.30-0.76) and mediation by a limited number of apparent genetic loci. Data comparing inbred strains have considerable utility as a tool for understanding the genetics of nociception, and a particular relevance to transgenic studies.