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While loss-of-function variants in the WAS gene are associated with Wiskott-Aldrich syndrome and lead to microthrombocytopenia, gain-of-function variants of WAS are associated with X-linked neutropenia (XLN) and the absence of microthrombocytopenia. Only a few XLN families have been reported so far, and their platelet phenotype was not described in detail. To date, no renal involvement was described in XLN. In the present study, we report exome sequencing of individuals from 3 generations of a family with a dominant disease combining neutropenia, macrothrombocytopenia, and renal failure. We identified a heterozygous missense gain-of-function variant in the WAS gene (c.881T>C, p.I294T) that segregates with the disease and is already known to cause XLN. There was no pathogenic variant in MYH9, TUBB1, or ACTN1. This is the first report of a WAS gain-of-function variant associated with both the hematological phenotype of XLN (neutropenia, macrothrombocytopenia) and renal disease (proteinuria, renal failure) with glomerular tip lesion hyalinosis and actin condensations in effaced podocytes foot processes.

Highlights • Robotic primary ventral hernia repair (PVHR) combines minimal access, closure of defect and pre-peritoneal mesh placement. • The protocol designs a randomized single-blinded controlled trial comparing robotic PVHR to open PVHR. • The primary outcome will be the incidence of wound-related complication within 1 month., Background The objective of the present study is to compare the outcomes open PVHR and robotic PVHR. Methods/Design The present study will be a randomized single-blinded controlled trial with intention-to-treat analysis comparing robotic PVHR to open PVHR in adult patients undergoing elective PVHR with a defect ranging between 1–5 cm. Patient refusing to participate, not able to give informed consent, with history of intra-abdominal surgery contraindicating a robotic surgical approach will be excluded. The intervention will consist in laparoscopic robotically assisted trans-abdominal pre-peritoneal epigastric or umbilical PVHR with closure of fascial defect and non-adsorbable mesh reinforcement. The control will be open pre-peritoneal epigastric or umbilical hernia repair with closure of fascial defect and non-absorbable mesh reinforcement. The primary outcome will be the incidence of wound-related complication within 1 month. The secondary outcomes will be esthetic satisfaction, pain, pain-killers consumption, general complications, costs, operative time and early hernia recurrence. Discussion Open PVHR is potentially associated to more wound-related complications, but has the advantages of cost-effectiveness, short operative time and totally extra-peritoneal repair. Laparoscopic PVHR has lower wound-related complications but implies placing the mesh in intra-peritoneal position, requires advanced laparoscopic skills, usually does not allow the closure of the defect, and can lead to excessive pain and pain-killers consumption. Robotic PVHR uses the same laparoscopic access as laparoscopic PVHR, but thanks to the extended range of motion given by the robotic system, allows defect closure, pre-peritoneal placement of the mesh and requires less technical skills. In the present randomized controlled trial, we expect to show that robotic PVHR leads to better wound-related outcomes than open PVHR. Trial registration The present randomized controlled trial was registered into clinicaltrials.gov under registration number NCT04171921.

Aim This study aims to describe the early results after implementing a robotic ventral hernia repair (RVHR) program in a European university center. Material and Methods All patients undergoing primary (PH) or incisional (IH) RVHR were included in an institutional open-label prospective quality database. Patients' baseline characteristics, intra-operative data, postoperative, and follow-up outcomes recorded from September 2018 to September 2020 were analyzed. Results Twenty-six PH and 58 IH were included; respectively, mean BMIs were 32.8±7.1 and 30.3±5.0kg/m2. Hernia resulted from median laparotomies in 69.0% of the IH patients; 5 patients (8.6%) had defects >10cm in width. In the PH group, the mean total operative room (OR) time was 98.1±42.5min. Mean VAS (Visual Analog Score) was 2.5±1.7 at day 0, 61.5% of patients were ambulatory, and 38.5% stayed 1-2 nights. One (3.8%) recurrence and 1(3.8%) surgical complication (umbilical perforation) occurred with no general complications. In the IH group, 15 patients required transversus abdominis release (TAR, 25.9%). Mean OR time was 179.6±82.3min, mean VAS 1.9±2.0 at day0, 19% of patients were ambulatory, 44.8% stayed 1-2 nights and 27.6% 3-4 nights. Mean follow-up was 71.6±51.8 days. One (1.7%) postoperative complication (bleeding, embolization, no reoperation), 2(3.4%) recurrences occurred. Successful completion of an extraperitoneal (eTEP) RVHR with bilateral TAR was achieved after 18 months and 40 cases, after which we began training a second surgeon. Conclusions Implementation of a RVHR program showed promising results with acceptable operative time even during the learning curve. Postoperative outcomes suggest a potential advantage in postoperative recovery.

Background In the panel of genes commonly associated with inherited macrothrombocytopenia, an important fraction encodes key cytoskeletal proteins such as tubulin isotypes, the building blocks of microtubules. Macrothrombocytopenia causing mutations have been identified in the TUBB1 and TUBA4A genes, emphasizing their importance in the formation of platelets and their marginal band, a unique microtubule ring-like structure that supports the platelet typical disc-shaped morphology. This raised the hypothesis that other tubulin isotypes normally expressed in platelets could play a similar role in their formation. Objectives To assess whether tubulin isotype genes other than TUBA4A and TUBB1 could be implicated in inherited macrothrombocytopenia. Methods We used high throughput sequencing to screen a cohort of 448 French blood donors with mild thrombocytopenia for mutations in a panel of selected genes known or suspected to be involved in platelet biogenesis. Results We identified six distinct novel mutations in TUBA8, which encodes the most-divergent α-tubulin, as the causative determinant of macrothrombocytopenia and platelet marginal band defects. Functionally, all TUBA8 mutations were found to fully or partially inhibit the incorporation of the mutated α8-tubulin in the microtubule network. Conclusion This study provides strong support for a key role of multiple tubulin genes in platelet biogenesis by discovering variants in a tubulin gene that was previously not known to be important for platelets.

Laboratory tests of platelet function are instrumental in studying platelet physiology and inherited or acquired platelet abnormalities. Light transmission aggregometry, developed in the early 1960s, is still considered the gold standard for the identification and diagnosis of platelet function disorders. Since then, novel techniques have been developed, including flow‐based assays and flow cytometry. In this tutorial, we describe the basic methodologies for the preparation of citrated platelet‐rich plasma and washed platelet suspensions and discuss their respective advantages and limitations as well as important factors to consider to perform high‐quality tests of platelet function. In addition, the methodologies of the main platelet function tests (light transmission aggregation, flow‐based assays, and flow cytometric assays) are described, and their respective strengths and limitations are discussed to assess various aspects of platelet biology.

Background Surgical wound infection contributes to prolonged recovery time after pilonidal sinus excision. As a standard procedure after surgery, we recommend our patients to perform water irrigations in the intergluteal cleft 4 to 6 times a day during the post-operative period. Our hypothesis is that this should reduce healing time and complication rates. The aim of this study was to measure the importance of sacro coccygeal hygiene in the management of pilonidal sinus disease. Methods We retrospectively collected data after surgical management of pilonidal sinus (sinusectomy procedures) in our division over a 10-year period. Patients were divided into three groups according to their local hygiene during postoperative follow-up and scored one (G1: good hygiene) to three (G3: poor hygiene). Primary outcome was complication rates. Secondary endpoints were, healing time, follow-up, time off work, and recurrence rate. Results In G1 (N = 112), complication rate was 3.6%. In G2 (N = 109), it was 5.5%, whereas in G3 (N = 71), it reached 7.03%. However, there were no statistically significant differences between hygiene groups regarding complication rates in both univariate and multivariable analysis. Regarding secondary outcomes, there were significant differences between hygiene groups concerning median follow-up (p = 0.0001) and median time off work (p = 0.0127). Conclusion Good hygiene of wound is essential for optimal, rapid healing without complications. The importance of this report is to show that thanks to our hygiene follow-up strategy with frequent perineal irrigations and regular follow-up checks, patients with at a first glance “unclean local conditions”, reached similar complications, median healing time and recurrences rates to patients with medium and good wound hygiene level.

Background\ud \ud Thrombocytopenia has a variety of different etiologies, both acquired and hereditary. Inherited thrombocytopenia may be associated with other symptoms (syndromic forms) or may be strictly isolated. To date, only about half of all the familial forms of thrombocytopenia have been accounted for in terms of well‐defined genetic abnormalities. However, data are limited on the nature and frequency of the underlying causative genetic variants in individuals with mild isolated nonsyndromic thrombocytopenia.\ud Study Design and Methods\ud \ud Thirteen known or candidate genes for isolated thrombocytopenia were included in a gene panel analysis in which targeted next‐generation sequencing was performed on 448 French blood donors with mild isolated nonsyndromic thrombocytopenia.\ud Results\ud \ud A total of 68 rare variants, including missense, splice site, frameshift, nonsense, and in‐frame variants (all heterozygous) were identified in 11 of the 13 genes screened. Twenty‐nine percent (N = 20) of the variants detected were absent from both the French Exome Project and gnomAD exome databases. Using stringent criteria and an unbiased approach, we classified seven predicted loss‐of‐function variants (three in ITGA2B and four in TUBB1) and four missense variants (one in GP1BA, two in ITGB3 and one in ACTN1) as being pathogenic or likely pathogenic. Altogether, they were found in 13 members (approx. 3%) of our studied cohort.\ud Conclusion\ud \ud We present the results of gene panel sequencing of known and candidate thrombocytopenia genes in mild isolated nonsyndromic thrombocytopenia. Pathogenic and likely pathogenic variants in five known thrombocytopenia genes were identified, accounting for approximately 3% of individuals with the condition.

Background: Careful assessment of bleeding history is the first step in the evaluation of patients with mild/moderate bleeding disorders, and the use of a bleeding assessment tool (BAT) is strongly encouraged. Although a few studies have assessed the utility of the ISTH-BAT in patients with inherited platelet function disorders (IPFD) none of them was sufficiently large to draw conclusions and/or included appropriate control groups. Objectives: The aim of the present study was to test the utility of the ISTH-BAT in a large cohort of patients with a well-defined diagnosis of inherited platelets disorder in comparison with two parallel cohorts, one of patients with type-1 von Willebrand disease (VWD-1) and one of healthy controls (HC). Patients/Methods: We enrolled 1098 subjects, 482 of whom had inherited platelet disorders (196 IPFD and 286 inherited platelet number disorders [IT]) from 17 countries. Results: IPFD patients had significantly higher bleeding score (BS; median 9) than VWD-1 patients (median 5), a higher number of hemorrhagic symptoms (4 versus 3), and higher percentage of patients with clinically relevant symptoms (score > 2). The ISTH-BAT showed excellent discrimination power between IPFD and HC (0.9

Ventral hernia surgery has undergone major changes over the past decade with the emergence of new minimally invasive techniques. They merge fundamental concepts of parietal reconstruction of open surgery into a laparoscopic approach, aiming to reduce surgical site complications and to enhance recovery. The spread of robotic assistance systems in the field of abdominal wall surgery facilitates access to this type of procedures and allows their application in increasingly complex cases. Parietal relaxation techniques allow large hernial orifices to be closed without tension. They are now also performed with a minimally invasive approach and in a less aggressive manner. Even if the exact place of all these techniques still needs to be better defined depending on the different hernia types, these laparoscopic or robot-assisted approaches already tend to allow faster post-operative recovery.Avec l’apparition de nouvelles techniques minimalement invasives, la chirurgie des hernies ventrales connaît depuis une dizaine d’années de profonds remaniements. Elles ont en commun d’intégrer les concepts fondamentaux de reconstruction pariétale de la chirurgie ouverte à une voie d’abord laparoscopique, dans le but de réduire les taux de complication du site opératoire et de permettre une réhabilitation accélérée. La diffusion des systèmes d’assistance robotique en chirurgie de la paroi facilite l’accès à ce type de procédure et permet d’envisager leur application dans des cas de plus en plus complexes. Les techniques de relaxation pariétale permettent la fermeture sans tension d’orifices herniaires larges. Elles sont maintenant aussi réalisées par voie minimalement invasive et de manière moins délabrante. Même si la place exacte de l’ensemble de ces techniques doit encore être mieux définie en fonction du type de hernie, ces prises en charge laparoscopiques ou robot-assistées semblent déjà permettre une récupération postopératoire plus rapide.

Platelet dense-granules are small organelles specific to the platelet lineage that contain small molecules (calcium, adenyl nucleotides, serotonin) and are essential for the activation of blood platelets prior to their aggregation in the event of a vascular injury. Delta-storage pool diseases (δ-SPDs) are platelet pathologies leading to hemorrhagic syndromes of variable severity and related to a qualitative (content) or quantitative (numerical) deficiency in dense-granules. These pathologies appear in a syndromic or non-syndromic form. The syndromic forms (Chediak–Higashi disease, Hermansky–Pudlak syndromes), whose causative genes are known, associate immune deficiencies and/or oculocutaneous albinism with a platelet function disorder (PFD). The non-syndromic forms correspond to an isolated PFD, but the genes responsible for the pathology are not yet known. The diagnosis of these pathologies is complex and poorly standardized. It is based on orientation tests performed by light transmission aggregometry or flow cytometry, which are supplemented by complementary tests based on the quantification of platelet dense-granules by electron microscopy using the whole platelet mount technique and the direct determination of granule contents (ADP/ATP and serotonin). The objective of this review is to present the state of our knowledge concerning platelet dense-granules and the tools available for the diagnosis of different forms of δ-SPD.

Major surgery is associated with an increased risk of venous thromboembolism, thus the application of mechanical or pharmacologic prophylaxis is recommended. The incidence of venous thromboembolism in patients with inherited platelet disorders undergoing surgical procedures is unknown and no information on the current use and safety of thromboprophylaxis, particularly of low-molecular-weight-heparin in these patients is available. Here we explored the approach to thromboprophylaxis and thrombotic outcomes in inherited platelet disorders patients undergoing surgery at venous thromboembolism-risk participating in the multicenter SPATA study. We evaluated 210 surgical procedures carried out in 155 patients with well-defined forms of inherited platelet disorders (venous thromboembolism-risk: 31% high, 28.6% intermediate, 25.2% low, 15.2% very low). The use of thromboprophylaxis was low (23.3% of procedures), with higher prevalence in orthopedic and gynecological surgeries, and was related to venous thromboembolism-risk. The most frequently employed thromboprophylaxis was mechanical and appeared to be effective, as no patients developed thrombosis, including patients belonging to the highest venous thromboembolism-risk classes. Low-molecular-weight-heparin use was low (10.5%) and it did not influence the incidence of post-surgical bleeding or of antihemorrhagic prohemostatic interventions. Two thromboembolic events were registered, both occurring after high venous thromboembolism-risk procedures in patients who did not receive thromboprophylaxis (4.7%). Our findings suggest that venous thromboembolism incidence is low in patients with inherited platelet disorders undergoing surgery at venous thromboembolism-risk and that it is predicted by the Caprini score. Mechanical thromboprophylaxis may be of benefit in patients with inherited platelet disorders undergoing invasive procedures at venous thromboembolism-risk and low-molecular-weight-heparin should be considered for major surgery. Fil: Paciullo, Francesco. Università di Perugia; Italia Fil: Bury, Loredana. Università di Perugia; Italia Fil: Noris, Patrizia. Universita Degli Studi Di Pavia; Italia Fil: Falcinelli, Emanuela. Università di Perugia; Italia Fil: Melazzini, Federica. Universita Degli Studi Di Pavia.; Italia Fil: Orsini, Sara. Università di Perugia; Italia Fil: Zaninetti, Carlo. Universita Degli Studi Di Pavia.; Italia Fil: Abdul Kadir, Rezan. Haemophilia Centre And Haemostasis Unit, Royal Free Fou; Reino Unido Fil: Obeng Tuudah, Deborah. Haemophilia Centre And Haemostasis Unit, Royal Free Fou; Reino Unido Fil: Heller, Paula Graciela. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Médicas. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Médicas; Argentina Fil: Glembotsky, Ana Claudia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Médicas. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Médicas; Argentina Fil: Fabris, Fabrizio. Università di Padova; Italia Fil: Rivera, Jose. Universidad de Murcia; España Fil: Lozano, Maria Luisa. Universidad de Murcia; España Fil: Butta, Nora. Hospital Universitario la Paz; España Fil: Favier, Remi. French Reference Centre For Inherited Platelet Disorder; Francia Fil: Cid, Ana Rosa. Hospital Universitario y Politecnico la Fe; España Fil: Fouassier, Marc. French Reference Centre For Inherited Platelet Disorder; Francia Fil: Podda, Gian Marco. Università degli Studi di Milano; Italia Fil: Santoro, Cristina. Università degli studi di Roma "La Sapienza"; Italia Fil: Grandone, Elvira. Casa Sollievo Della Sofferenza,s.giovanni Rotondo; Italia Fil: Henskens, Yvonne. Maastricht University Medical Centre; Países Bajos Fil: Nurden, Paquita. French Reference Centre For Inherited Platelet Disorder; Francia Fil: Zieger, Barbara. Albert Ludwigs University of Freiburg; Alemania Fil: Cuker, Adam. University of Pennsylvania; Estados Unidos Fil: Devreese, Katrien. University of Ghent; Bélgica Fil: Tosetto, Alberto. Hospital San Bortolo; Italia Fil: De Candia, Erica. Istituto Nazionale di Ricovero e Cura a Carattere Scientifico "Saverio de Bellis"; Italia Fil: Dupuis, Arnaud. French Reference Centre For Inherited Platelet Disorder; Francia Fil: Miyazaki, Koji. Kitasato University School Of Medicine; Japón Fil: Othman, Maha. Queens University; Canadá Fil: Gresele, Paolo. Università di Perugia; Italia

Inherited platelet disorders are rare bleeding syndromes due to either platelet function abnormalities or thrombocytopenia which may be associated with functional defects. The haemorrhagic symptoms observed in these patients are mostly muco-cutaneous and of highly variable severity. Although 30 to 50% of the platelet disorders are still of unknown origin, the precise diagnosis of these pathologies by specialized laboratories together with haemorrhagic scores enables an assessment of the risk of bleeding in each patient. Depending on the diagnostic elements collected, an appropriate medical procedure can be proposed for each situation: scheduled or emergency surgical interventions and pregnancy follow-up. The pathologies most at risk correspond to Glanzmann's thrombasthenia, Bernard-Soulier syndrome, severe thrombocytopenia (

Chronic pain is frequent after Roux-en-Y gastric bypass (RYGB). Recurrent internal hernias (IHs) may be responsible for chronic abdominal pain. Physical examination and computed tomography are often inconclusive. This observational retrospective study describes 11 patients who underwent elective laparoscopy for post-RYGB chronic abdominal pain of undetermined etiology after noninvasive investigations and failure of conservative treatment. Open intermesenteric and/or Peterson spaces were found in all cases; IH was present in 6 cases. Nine patients were totally relieved from symptoms after mesenteric windows closure; substantial improvement was noted in the remaining 2 cases. Peterson space was found more likely to be responsible for chronic IH. In such selected patients, laparoscopic exploration and windows closure should be discussed. These findings add support to initial windows closure during RYGB.

Alpha4A-tubulin is the predominant α-tubulin isotype in platelets. Mutations in α4A-tubulin cause abnormal platelet biogenesis and marginal band formation in mice and in a patient, establishing an essential role of this tubulin isotype., During platelet biogenesis, microtubules (MTs) are arranged into submembranous structures (the marginal band) that encircle the cell in a single plane. This unique MT array has no equivalent in any other mammalian cell, and the mechanisms responsible for this particular mode of assembly are not fully understood. One possibility is that platelet MTs are composed of a particular set of tubulin isotypes that carry specific posttranslational modifications. Although β1-tubulin is known to be essential, no equivalent roles of α-tubulin isotypes in platelet formation or function have so far been reported. Here, we identify α4A-tubulin as a predominant α-tubulin isotype in platelets. Similar to β1-tubulin, α4A-tubulin expression is up-regulated during the late stages of megakaryocyte differentiation. Missense mutations in the α4A-tubulin gene cause macrothrombocytopenia in mice and humans. Defects in α4A-tubulin lead to changes in tubulin tyrosination status of the platelet tubulin pool. Ultrastructural defects include reduced numbers and misarranged MT coils in the platelet marginal band. We further observed defects in megakaryocyte maturation and proplatelet formation in Tuba4a-mutant mice. We have, thus, discovered an α-tubulin isotype with specific and essential roles in platelet biogenesis.

Les granules denses plaquettaires sont des organites contenant des molecules non peptidiques : calcium, serotonine, nucleotides et phosphates inorganiques. Lors de l’activation plaquettaire, ils fusionnent avec la membrane plasmique afin de secreter leur contenu dans le milieu exterieur. La maladie du pool vide δ-plaquettaire correspond a une anomalie du nombre et/ou du contenu en granules denses. Les etiologies de cette maladie sont diverses et variees. On distingue (1) les formes constitutionnelles, qui peuvent etre isolees ou s’inscrire dans le cadre de syndromes plus complexes (syndromes d’Hermansky–Pudlak, Chediak–Higashi, ou Griscelli) ; et (2) les formes acquises, qui sont le plus souvent associees a des hemopathies malignes (syndrome myelodysplasique, leucemie aigue, syndrome myeloproliferatif, ou autres). La prevalence de la maladie du pool vide δ-plaquettaire dans sa forme isolee est probablement sous-estimee, principalement parce que cette pathologie est peu connue et que son diagnostic biologique est relativement complexe. Les patients souffrant de deficit en granules denses ont generalement un phenotype hemorragique modere. Neanmoins, certains d’entre eux peuvent avoir des manifestations hemorragiques severes notamment en situation chirurgicale ou traumatique. C’est donc une thrombopathie qui doit etre diagnostiquee et prise en compte, en particulier lorsqu’il est necessaire de realiser des gestes a risque hemorragique. In vitro, les deficits en granules denses sont associes a une reduction de l’agregation dans les conditions ou celle-ci est particulierement sensible, c’est-a-dire aux faibles concentrations d’agonistes. Cependant, le profil d’agregation peut ne pas etre altere ou donner des resultats atypiques et dissocies. C’est pourquoi, la confirmation diagnostique necessite la realisation d’examens tres specialises afin de demontrer la diminution du nombre ou du contenu en granules denses. En l’etat actuel des connaissances, il est recommande, dans la mesure du possible, de realiser des dosages de serotonine, une quantification des nucleotides, ainsi qu’une etude des granules denses par microscopie electronique (whole mount). La maladie du pool vide δ-plaquettaire est donc une pathologie complexe presentant des aspects cliniques et biologiques tres divers, requerant une grande expertise afin de ne pas ignorer son diagnostic.

During platelet biogenesis, microtubules (MTs) are arranged into submembranous structures (the marginal band) that encircle the cell in a single plane. This unique MT array has no equivalent in any other mammalian cell, and the mechanisms responsible for this particular mode of assembly are not fully understood. One possibility is that platelet MTs are composed of a particular set of tubulin isotypes that carry specific posttranslational modifications. Although β1-tubulin is known to be essential, no equivalent roles of α-tubulin isotypes in platelet formation or function have so far been reported. Here, we identify α4A-tubulin as a predominant α-tubulin isotype in platelets. Similar to β1-tubulin, α4A-tubulin expression is up-regulated during the late stages of megakaryocyte differentiation. Missense mutations in the α4A-tubulin gene cause macrothrombocytopenia in mice and humans. Defects in α4A-tubulin lead to changes in tubulin tyrosination status of the platelet tubulin pool. Ultrastructural defects include reduced numbers and misarranged MT coils in the platelet marginal band. We further observed defects in megakaryocyte maturation and proplatelet formation inTuba4a-mutant mice. We have, thus, discovered an α-tubulin isotype with specific and essential roles in platelet biogenesis.

Background Accurate identification of the proportion of young platelets is important to distinguish peripheral thrombocytopenia from a deficit in platelet production. Young platelets are defined by their higher RNA content and are often assessed as thiazole orange bright (TObright ) by flow cytometry. In clinical practice, their proportion is estimated by automatic blood counter according to their greater RNA content, which identifies a so-called immature platelet fraction (IPF). However, the detected IPFs are not strictly identical to the young TObright platelet population observed by flow cytometry. Objectives The aim of this study was to assess the reliability of HLA I/major histocompatibility I (MHC I) cell surface expression as a marker of young platelets. Methods The HLA I/MHC I expression was evaluated by flow cytometry after costaining blood with TO and antibodies directed against HLA I/MHC I molecules. Results We found that platelets with a higher expression of plasma membrane-localized MHC I molecules displayed an increased TO staining and a higher content in ribosomal P-antigen. Transfusion experiments in mice showed that the number of MHC I molecules expressed on the cell surface of young murine platelets decreased during platelet aging, reaching basal levels within 24 h. Finally, we demonstrated that for patients with thrombocytopenias, the identification of young platelets is better assessed by the flow cytometric determination of the level of HLA I expression than by TO staining or the use of hematological blood counter. Conclusion Overall, our results highlight the relevance of MHC I/HLA I expression as a valuable parameter to identify young platelets.

Background Splenic abscess usually arises from hematogenous spread. Causative pathogens are various and anaerobic pathogens are rarely reported. Case presentation We report the case of a 50-year-old male patient who was admitted for sepsis due to gangrenous necrosis of the spleen associated with bacteremia. Causative pathogens were Clostridium perfringens and Streptococcus gallolyticus. The patient was successfully treated by splenectomy and targeted intravenous antibiotics. No underlying or predisposing disease was found. Conclusion Gangrenous necrosis of the spleen is a rare entity that can be successfully treated by splenectomy and antibiotics.

BACKGROUND Ehlers-Danlos syndrome (EDS) is a heterogeneous group of rare inherited diseases involving connective tissue. Vascular EDS (vEDS) is associated with abnormal type III collagen, which is an essential component of skin, hollow organs and arterial walls, and causes potentially fatal visceral and arterial complications. The surgical management of these patients is challenging and should be limited to life-saving procedures. CASE DESCRIPTION We report a case of a 42-year-old male who presented a hemorrhagic shock due to spontaneous rupture of an ascending branch of the left colic artery. The coexisting presence of multiple abdominal vascular abnormalities suggested the diagnosis of vEDS, later confirmed by the discovery of a new missense mutation in the COL3A1 gene with pathogenic significance. The post-operative course was marked by a mechanical ileus caused by an ischemic stenosis of the descending colon. Failure of conservative management and the well-known risk of colonic perforation in these patients led to the decision to perform a diverting ileostomy. CONCLUSION The management of these patients is difficult, and risk-benefit assessments must be made on a case-by-case basis. Less invasive procedures should be considered whenever possible.

SummaryThe platelet adenosine 5’-diphosphate (ADP) receptor P2Y12 (P2Y12R) plays a critical role in platelet aggregation. The present report illustrates an update of dysfunctional platelet P2Y12R mutations diagnosed with congenital lifelong bleeding problems. Described patients with heterozygous or homozygous substitution in the P2Y12R gene and qualitative abnormalities of the platelet P2Y12R are summarized. Recently, a further dysfunctional variant of P2Y12R has been identified in two brothers who presented with a lifelong severe bleeding disorder. During in vitro aggregation studies, the patient´s platelets show a markedly reduced and rapid reversible ADP-promoted aggregation. A homozygous c.561T>A substitution that changes the codon for His187 to Gln (p.His187Gln) in the P2Y12R gene has been identified. This mutation causes no change in receptor expression but decreases the affinity of the ligand for the receptor, even at high concentrations. Structure modelling studies indicated that the p.His187Gln mutation, located in the fifth transmembrane spanning domain (TM5), impairs conformational changes of the receptor. Structural integrity of the TM5 region is necessary for agonist and antagonist binding and for correct receptor function.

International audience; The preparation of non-symmetric Schiff base ligands possessing one oxime function that is associated to a second function such as pyrrole or phenol function is first described. These ligands, which possess inner N4 or N3O coordination sites, allow formation of cationic or neutral non-symmetric CuII or NiII metallo-ligand complexes under their mono- or di-deprotonated forms. In presence of Lanthanide ions the neutral complexes do not coordinate to the LnIII ions, the oxygen atom of the oxime function being only hydrogen-bonded to a water molecule that is linked to the LnIII ion. This surprising behavior allows for the isolation of LnIII ions by non-interacting metal complexes. Reaction of cationic NiII complexes possessing a protonated oxime function with LnIII ions leads to the formation of original and dianionic (Gd(NO3)5)2− entities that are well separated from each other. This work highlights the preparation of well isolated mononuclear LnIII entities into a matrix of diamagnetic metal complexes. These new complexes complete our previous work dealing with the complexing ability of the oxime function toward Lanthanide ions. It could open the way to the synthesis of new entities with interesting properties, such as single-ion magnets for example.

Background and objectives Small batch-pooled (mini-pool) whole blood (WB)-derived plasma could be an alternative cost-effective source of therapeutic plasma (TP), but carries an increased risk of transfusion-transmitted infection due to exposure of the recipient to several donors. This risk can be mitigated by inactivation of pathogens susceptible to the amotosalen-UVA (AUVA)-treatment. We evaluated the conservation of coagulation factors in AUVA-plasma prepared from WB stored overnight under routine operating conditions, to determine its therapeutic efficacy. Thrombin generation (TG) by the AUVA-plasma was used to provide an integrated measure of the hemostatic capacity. Materials and methods WB-donations (~450 ml) stored overnight were processed to prepare five leucocyte-depleted plasma mini-pools (1300 ml), which were divided into two parts and treated with AUVA. Each mini-pool yielded six AUVA-plasma units (200 ml) which were frozen (-25°C) within 19 h of WB-collection. Their hemostatic quality was evaluated before and after treatment for up to 12 months of storage. Results Immediately after AUVA-treatment, the regulatory criteria for FVIII activity and fibrinogen content were met. As compared to untreated plasma there was a reduction in fibrinogen (14%), FV (9%), FVII (25%) and FVIII (32%). However, TG was similar in treated and untreated plasma at all-time-points. Conclusions Frozen WB-derived AUVA-plasma prepared from mini-pools within 19 h of WB-collection met the quality standards required for TP and retained hemostatic capacity for up to 12 months. This product could provide a cost-effective convenient substitute for apheresis plasma.

Glycoprotein VI, a major platelet activation receptor for collagen and fibrin, is considered a particularly promising, safe antithrombotic target. In this study, we show that human glycoprotein VI signals upon platelet adhesion to fibrinogen. Full spreading of human platelets on fibrinogen was abolished in platelets from glycoprotein VI- deficient patients suggesting that fibrinogen activates platelets through glycoprotein VI. While mouse platelets failed to spread on fibrinogen, human-glycoprotein VI-transgenic mouse platelets showed full spreading and increased Ca2+ signaling through the tyrosine kinase Syk. Direct binding of fibrinogen to human glycoprotein VI was shown by surface plasmon resonance and by increased adhesion to fibrinogen of human glycoprotein VI-transfected RBL-2H3 cells relative to mock-transfected cells. Blockade of human glycoprotein VI with the Fab of the monoclonal antibody 9O12 impaired platelet aggregation on preformed platelet aggregates in flowing blood independent of collagen and fibrin exposure. These results demonstrate that human glycoprotein VI binds to immobilized fibrinogen and show that this contributes to platelet spreading and platelet aggregation under flow.

Contexte La biotine (Biot) est une alternative aux sondes radioactives pour tracer les cellules sanguines. Elle permet de suivre simultanement in vivo plusieurs populations de cellules marquees a differentes densites de Biot. Une seule etude decrit le suivi d’une population de Biot-plaquettes (PLTs) chez l’homme (Stohlawetz, 1999). Objectif Il s’agit de marquer des PLTs humaines avec differents niveaux de Biot afin de determiner si la biotinylation affecte leurs fonctions. C’est une etude preliminaire pour explorer la faisabilite de produire des Biot-PLT multi-marquees pour des etudes cliniques. Methode Les PLTs en Tyrode's albumine (TA) sont incubees avec de la sulfo-NHS-Biot (0, 4,5, 45 et 180 μM), lavees 2 fois et resuspendues en TA/PPPcit (v/v). La densite de Biot est controlee en cytometrie en flux (CF) avec la streptavidine-PE et les fonctions des PLTs evaluees sur les criteres de secretion, integrite des glycoproteines (GP) et agregation. Resultats Les populations de Biot-PLTs sont distinguees en CF. L’externalisation de la P-selectine apres activation au TRAP est stable de 0 a 45 μM de Biot et un peu diminuee pour 180 μM. L’expression de GPIb et GPIIbIIIa est normale pour toutes les Biot-PLTs. L’agregabilite a l’acide arachidonique (AA) est preservee pour toutes les Biot-PLTs. La Biot diminue la reponse a l’ADP et au collagene de facon dose dependante avec une agregation des Biot180-PLTs abolie avec l’ADP ( Tableau 1 ). Conclusion Les principales fonctions plaquettaires : secretion, integrite des GP et agregation en reponse a l’agoniste fort l’AA, sont pleinement conservees pour toutes les densites de Biot. Mais la biotinylation affecte la reponse a l’ADP et au collagene. Le multi-marquage a la Biot serait approprie pour reperer les PLTs lors d’etudes cliniques pourvues que des concentrations de Biot

Les thrombopenies constitutionnelles resultent d’anomalies de production des plaquettes sanguines (thrombopoiese) d’origine hereditaire. Les connaissances autour de ces maladies, longtemps mal diagnostiquees et peu etudiees, ont considerablement augmente ces vingt dernieres annees. L’essor des techniques de biologie moleculaire permettant l’identification des mutations et la culture de megacaryocytes provenant de patients, permise par la decouverte de la thrombopoietine, ont grandement contribue a ces progres. Parallelement, la manipulation des genes dans la souris (transgenese, inactivation totale ou conditionnelle, creation de mutations ponctuelles reproduisant les mutations humaines, mutagenese chimique aleatoire) a permis de creer des modeles de maladies qui ont grandement contribue au decryptage des tableaux cliniques et biologiques presentes par les patients. La plupart des thrombopenies pour lesquelles le gene mute a ete identifie ont maintenant un modele d’etude murin. La mise en relation des donnees obtenues dans ces modeles et dans les cellules isolees de patients a abouti a une meilleure comprehension des pathologies et des mecanismes normaux de production des plaquettes. Il reste que pres de la moitie des thrombopenies constitutionnelles sont encore non etiquetees. L’essor du sequencage a haut debit du genome devrait augmenter le nombre de genes candidats que la generation de nouveaux modeles murins permettra de confirmer comme cause de la maladie.

Objective We reviewed our experience of total laparoscopic aortic bypass surgery performed for aortoiliac occlusive disease (AIOD), focusing on early 30-day mortality and morbidity and short-term and midterm outcomes. Methods A monocentric retrospective study was conducted between October 2002 and October 2011; we performed 173 total laparoscopic aortic surgeries to treat AIOD. Results Patients included 135 men and 38 women. The mean age was 57.2 years (range, 34-77 years). The median operative time was 205 minutes (range, 120-420 minutes), the median aortic clamping time was 50 minutes (range, 20-120 minutes), and the mean blood loss was 263 mL (range, 0-3200 mL). Conversion to open surgery was necessary in 12.1% of patients. The 30-day postoperative mortality rate was 2.3% (four of 173 patients). Major morbidity occurred in 6.9% of patients. Wound complications occurred in 8%. Four patients had a groin infection (2.3%), treated by surgical trimming in three patients and replacement of the prosthesis by venous bypass in one patient. Early graft thrombosis (within 30 days) occurred in one patient (0.6%), requiring reintervention. With a mean follow-up of 42 months (standard deviation, 37 months), 96% of bypasses were patent. Patency rates at 3 and 5 years were 97% and 85% respectively. Conclusions In selected patients, laparoscopic aortic bypass surgery for AIOD is a safe procedure with an acceptable morbidity rate, short intensive care unit and hospital stay, fast recovery, and early return to general diet. It is a good indication after failure of endovascular surgery.

SummaryWe studied haemostasis in two mouse models with thrombocytosis caused by different pathogenic mechanisms. In one strain (Yall;Mpl-/-) thrombocytosis is driven by a misbalance between thrombopoietin and its receptor, whereas in the other strain, thrombocytosis is caused by expressing a human JAK2-V617F transgene (FF1) that depends on activation by Cre-recombinase (VavCre;FF1, MxCre;FF1). Thrombotic responses were increased following some, but not all types of challenges. In a vaso-occlusive thrombotic model following collagen-adrenaline injection we found increased mortality in both strains. Arterial thrombosis, examined after ferric chloride-induced carotid injury, was accelerated but with little impact on maximal thrombus size. In a vena cava stasis model, clots were of similar size as in wild-type controls, but exhibited a different composition with a higher platelet to fibrin ratio. Both thrombocytosis strains displayed increased haemorrhagic tendency in a tail bleeding assay. Yall;Mpl and VavCre;FF1 displayed a lower proportion of the more reactive high-molecular-weight forms of von Willebrand factor in their plasma, mimicking essential thrombocythaemia with very high platelet counts. Bleeding could not be explained by clear defects in platelet activation, which were normal or only weakly decreased. In conclusion, these models of thrombocytosis recapitulate several features of the haemorrhagic and thrombotic diatheses in ET and PV demonstrating potentials but also some limitations to study these major complications.