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The paper addresses a supply network design problem in which a set of enterprises decides to organise itself as a multi-stage supply network by resource sharing and production coordination. A biform game theory formulation of the problem is obtained by combining the cooperative sub-game in the manufacturing network with the strategic sub-game of the Stackelberg type between the retailer and the manufacturers’ network. As a result of the interaction between these two sub-games, a new type of cooperative game, the quadratic production game, is formulated to describe the supply network design problem under anticipated price elastic demands from the market. The key problem of coalitional stability is addressed through the properties of rationality and fairness of the profit sharing agreement. We prove that the game is non-convex in general and thus, the fair solution given by the Shapley value allocation is not always rational. It is proposed to reinforce the coalition stability by selecting a minimal set of partner enterprises achieving the maximal expected profit and applying a profit sharing policy with guaranteed fairness restricted to the member enterprises. [ABSTRACT FROM PUBLISHER]

We describe a new δ-globin variant, Hb A2-Tunis [δ46(CD5)Gly → Glu; HBD: c.140G>A]. This hemoglobin (Hb) variant displayed a faster electrophoretic mobility than normal Hb A2 and was expressed at 3.2%. The molecular defect was characterized by DNA sequencing analysis. Hb A2-Tunis was found in a carrier of a β0-thalassemia (β0-thal) [IVS I-1 (β143, G>A); HBB: c.92 + 1G>A] and Hb C [β6(A3)Glu → Lys; HBB: c.19G>A], presenting with a normal Hb A2 level. Phenotype and genotype investigations revealed that the patient has a total Hb A2 level of 7.1% that was expected for a β-thalassemia (β-thal) minor carrier. [ABSTRACT FROM AUTHOR]

Introduction: Platelet count is crucial for clinical decision. In cases of microcytosis, platelet count based on impedance technique (PLT-I) may overestimate platelet count., Aim: To compare PLT-I with platelet count using the optical technique (PLT-O) and establish a Mean Corpuscular Volume (MCV) threshold for considering PLT-O., Methods: A prospective analytical study conducted over two months involved blood samples collected in standard K2 EDTA tubes for complete blood count analysis, revealing microcytosis (MCV<80 fL). PLT-O analysis in channel-Ret mode was performed using the Sysmex-XN1000 (Sysmex Corporation, Kobe, Japan). Percentage of fragmented red cells (FRC%) and percentage of microcytic red cells (Micro-R%) were recorded. Blood smears stained with May-Grünwald-Giemsa were examined for potential interfering particles., Results: A strong correlation was observed between the two techniques for all platelet values as well as for PLT <150 x 109/L (correlation coefficient r = 0.971, 95% CI: [0.956-0.982]; P<10-3 and r = 0.90, 95% CI: [0.79-0.95]; P< 10-3). The Bland-Altman plot revealed a bias of 16.53 x 109/L between the two methods, with agreement limits between -55.8 and 88.8 x 109/L. A threshold MCV value indicating the use of the optical method, with a cut-off at 72.9fL, demonstrated promising performance consistent with literature findings. However, less favorable performance was observed with Micro-R%., Conclusion: Impedance could be employed in routine practice. However, for MCV<72.9 fL or in the presence of schizocytes, the hemogram validation procedure may incorporate the use of PLT-O.

Introduction: Massive transfusion (MT) is a life-saving therapy in situations of major hemorrhage awaiting radical haemostatic treatment. Poor management and control of this therapy may, however, compromise the patient's vital prognosis. The main aim of our study was to take stock of massive transfusion practices in Tunisia. The secondary aim was to propose a massive transfusion protocol., Methods: An analytical observational study based on a questionnaire was conducted. We targeted physicians brought in their clinical practice to use MT., Results: A total of 124 clinicians responded to the questionnaire. The majority (62%) were anesthesiologists or emergency physicians. More than half of the participants were residents (51%). The use of MT based on a clinical or biological score was only found for a minority (13%). The initial order was for the majority of participants (N=69) made up of red blood cell concentrates (RBC) and fresh frozen plasma (FFP). The FFP: RBC ratio was1:2 for 51% of the participants. A higher ratio was adopted by the rest. Respectively 23.5% and 9.6% of participants transfused platelets and fibrinogen concentrates without waiting for the result of biology. The use of tranexamic acid was systematically advocated by 60.5% of clinicians. The majority (86.3%) adopted a restrictive transfusion strategy (target hemoglobin between 7 and 9 g/dl). The latter was more adopted by the youngest physicians (92.1% of residents versus 55.6% of professors; p=0.008)., Conclusions: The professional practices of MT in Tunisia are heterogeneous. Given the lack of a clear institutionalized procedure which frames this therapy, a MT protocol has thus been proposed.

Background: B12 Vitamin deficiency is common in adults (20% of general population of industrialized populations), especially in elderly patients (30-40%). The etiologies of Vitamin B12 deficiency have been dominated by the cobalamin syndrome nutrient and the Biermer disease, rarely by the intake or nutritional deficiency and bad absorptions., Study Objective: Establish an etiology of vitamin B12 in a Tunisian population Methods: In a prospective study involving 100 patients with macrocytic anemia, a comprehensive assessment has been carried out of: B12 vitamin and folate intake, homocysteine, immunological assessment (antibodies, intrinsic anti-factor and anti-gastric parietal cells), an endoscopic exploration, and a dietary nutritional survey., Results: The mean age of patients was 53.6 ± 17,6 years (13 - 88 years), the gender ratio (female/male) is 1.22. The clinical symptomatology shows a functional anemia syndrome in 89% of cases, a digestive syndrome in 88% of cases, and neurological disorders in 67% of cases. The intake of B12 vitamin was reduced (<180 pg/ml) in 99 patients, associated with a hyperhomocysteinemia in 81.63% of cases.The intrinsic anti-factor antibodies were positives in 32 patients, and the antibody anti-gastric parietal cells in 85 patients. Gastric biopsy was performed in 54 patients, showing a chronic atrophic gastritis of fundic localization in 44 patients, antral in 5 patients and pan- gastric in 3 patients. The diagnosis of Biermer anemia was held in 75% of patients, that of FCS in 16% of patients, and a lack of intake in 8% of patients. The etiology was undetermined in 1% of cases., Conclusion: Vitamin B12 deficiency is common in the general population, its causes and origins are multiple, we list them in order of occurrence: Biermer disease, the FCS, and the intake deficiency in our population.

Background: BCR-ABL negative myeloproliferative neoplasms (MPN) include polycythemia Vera (PV), essential thrombocythemia (ET) and primitive myelofibrosis (PMF). the JAK2 V617F mutation has been introduced since 2008 as a major diagnostic criterion on the one hand and on the other hand, it would be linked to increased risk of thrombotic complications., Aim: This study aimed to evaluate the association of JAK2 mutation and thrombotic events in MPN., Methods: A retrospective study concerning 45 BCR-ABL negative MPN patients (mean age=53 old years, sex ratio=0.8) was conducted., Results: They were classified as PV (22 patients), ET (17 patients), PMF (3 patients) and atypical MPN (3 patients). The JAK2 mutation was found in 64.4% of patients: 72.7% of PV patients, 47% of ET patients and 66.7% of PMF patients. Thrombotic events were recorded in 11 patients (24.4%). Cerebral arteries and portal vein were the most frequent localizations. The JAK2 mutation was an independent risk factor of thrombotic events., Conclusion: Consequently, it seems that screening for JAK2 mutation in BCR-ABL negative MPN could play a role in identifying patients at high risk of vascular complications.

Background: The management of urolithiasis in patients with haemophilia poses a real challenge to the urologist., Aim: We conducted a systematic literature review to assess the safety and efficacy of extracorporeal shock wave lithotripsy (ESWL) in the treatment of urolithiasis in hemophiliacs., Methods: A systematic review was conducted by using the National Library of Medicine (PubMed) search engine between January 1985 and June 2013. We've used these key words: "haemophilia" and "extracorporeal shock wave lithotripsy". All articles dealing with the treatment of nephrolithiasis by ESWL in patients with hemophilia were included. Two independent reviewers extracted the data from each article. The data was included into a systematic review and analyzed., Results: A total of 12 medical articles were selected with a total of 25 patients. The stone size varies from 6 to 21 mm. The substitution of the deficient clotting factor started the day before the ESWL. ESWL was effective in all patients except one after 1-6 sessions / patient. An ultrasound was performed after the procedure to look for potential bleeding complications. The judgment of the substitution therapy depends on the patient's condition, the presence of hematuria and the absence of signs of bleeding. Major bleeding complications were observed in 4 patients., Conclusions: With effective substitution of deficient clotting factors, ESWL is a safe and low morbidity method in the treatment of urinary calculi in hemophiliacs.

We describe a new δ-globin variant, Hb A2-Tunis [δ46(CD5)Gly → Glu; HBD: c.140G>A]. This hemoglobin (Hb) variant displayed a faster electrophoretic mobility than normal Hb A2 and was expressed at 3.2%. The molecular defect was characterized by DNA sequencing analysis. Hb A2-Tunis was found in a carrier of a β(0)-thalassemia (β(0)-thal) [IVS I-1 (β143, G>A); HBB: c.92 + 1G>A] and Hb C [β6(A3)Glu → Lys; HBB: c.19G>A], presenting with a normal Hb A2 level. Phenotype and genotype investigations revealed that the patient has a total Hb A2 level of 7.1% that was expected for a β-thalassemia (β-thal) minor carrier.

Background: Blood transfusion is a high risk activity., Aim: To evaluate transfusion safety in planned cardiac surgery., Methods: This study was conducted in the blood bank of the Rabta Hospital in two phases: a phase to observe transfusion acts followed by corrective actions and a phase to evaluate the impacts of these corrections on the transfusion practices. Characteristics of the potentially transfused patients, the eventually prescribed, dispensed and transfused blood products and transfusion practices were studied., Results: During the observation phase, 70 patients were enrolled, 51 potentially transfused. Weaknesses concerned the mention of phenotype and transfusion history when ordering blood components as well as the double ABO/D group typing, the phenotype and the cross match performing. Final bedside controls were done in a wrong way. The distribution and the blood administration were established respectively for 208 and 232 blood products. The traceability was established for 86 blood products. During the evaluation phase, 30 patients were enrolled, 15 potentially transfused. Improvement was achieved in the transfusion history notification, phenotype and antibodies screen performing and cross matching., Conclusion: Optimisation of blood transfusion can be conceived only with collaboration between the different transfusion structures.

Background: The pathogenesis of myocardial infarction (MI) in young involves new factors including constitutional or acquired thrombophilia., Aim: To determine in patients ² 50 years, the association between coagulation factors deficiency, myocardial infarction and cardiovascular events during follow-up., Methods: Protein C (PC), PS and antithrombin (AT) were screened in 50 patients admitted for acute MI and in a healthy control group. Univariate and multivariate analysis were performed using SPSS 11.5 version., Results: PS and PC deficiency were associated to MI (respectively 24% vs 0%, p=0.001 and 14% vs 0%, p=0.016), independently for PC. No AT deficiency was detected in both groups. During followup, PS and C deficiency were predictive for venous thrombosis (p<0.05) and PS deficiency for pulmonary embolism., Conclusion: Protein C and S deficiency may play an important role in MI in young and also in thromboembolic complications during follow-up. Nevertheless, therapeutic implications remain controversial.

Background: Diabetes is one of the principal cause of blindness in adults. The aim of the study is to evaluate the frequency of ocular complications and risk factors of diabetes. It's a multicentric prospective study on a representative sample of 285 diabetics., Methods: We performed a general and an ophthalmologic exam for all patients with retinal angiography and appropriate laboratory tests. Chi 2, Fisher, Mann and Whitney tests were used as statistical methods., Results: Diabetic retinopathy was observed in 45,2% of patients, cataract in 22%, glaucoma in 5%. Diabetic retinopathy frequency rises especially with duration of diabetes and bad glycaemic control. Blindness related to diabetic retinopathy was observed in 6,25% and visual deficiency in 12,5%. The authors compared their results with literature data. They emphasize on the great value of regular better glycaemic control and other associated metabolic disorders., Conclusion: We concluded that a regular ophthalmologic follow up is necessary for early diabetic retinopathy detection and treatment.