Tensile Behavior of High-Strength,Strain-Hardening Cement-Based Composites (HS-SHCC) Reinforced with Continuous Textile Made of Ultra-High-Molecular-Weight Polyethylene

The paper at hand presents an investigation of the tensile behavior of high-strength, strain-hardening cement-based composites (HS-SHCC), reinforced with a single layer of continuous, two-dimensional textile made of ultra-high molecular weight polyethylene (UHMWPE). Uniaxial tension tests were performed on the bare UHMWPE textiles, on plain HS-SHCC, and on the hybrid fiber-reinforced composites. The bond properties between the textile yarns and the surrounding composite were investigated in single-yarn pullout experiments. In order to assess the influence of bond strength between the yarn and HS-SHCC on the tensile behavior of the composites with hybrid fiber reinforcement, the textile samples were analyzed both with, and without, an additional coating of epoxy resin and sand. Compared to the composites reinforced with carbon yarns in previous studies by the authors, the high elongation capacity of the UHMWPE textile established the higher strain capacity of the hybrid fiber-reinforced composites, and showed superior energy absorption capacity up to failure. The UHMWPE textile limited the average crack width in comparison with that of plain HS-SHCC, but led to slightly larger crack widths when compared to equivalent composites reinforced with carbon textile, the reason for which was traced back to the lower Young’s modulus and the higher elongation capacity of the polymer textile.     

Cerebral venous thrombosis and Behcet's disease

Behcet's disease is a chronic relapsing multisystem disorder of unknown etiology. Neurological complications are frequent, occurring in 10 to 49% of cases. We report 4 cases with Behcet's disease (3 females and 1 male) who had symptomatic intracranial hypertension due to cerebral venous sinus thrombosis within a mean delay of 2 years. The mean age at onset was 31 years and the mean age on referral was 39.5 years. The predominant manifestation in our series were headache, papilledema, seizures and pyramidal syndromes. CT Scan showed non specific abnormalities in all of them and the sinus venous thrombosis was confirmed by MRI in 3 cases. The authors emphasize on the importance of MRI with angio MRI for the diagnosis, the outcome and the evaluation of the cerebral venous thrombosis after treatment.     

Gastrointestinal manifestations in severe scorpion envenomation

OBJECTIVES: To evaluate the type and incidence of gastrointestinal manifestations secondary to scorpion envenomation and their prognostic significance. PATIENTS AND METHODS: All patients admitted to our ICU for scorpion envenomation were included in this retrospective chart review of a 13-year period (1990 - 2002). RESULTS: During the study period, 951 patients were admitted for scorpion envenomation and 72 (7.6%) died. Ages ranged from 0.5 to 90 years with a mean of 14.7 +/- 17.4 years. Gastrointestinal symptoms were present in 700 patients (73.6%): nausea in 24 (2.5%), vomiting in 687 (72.2%) and diarrhea in 41 patients (4.3%). At univariate analysis, the presence of diarrhea was associated with a fatal outcome (P < 0.05). Diarrhea was also correlated with other indicators of severe envenomation and poor prognosis: respiratory failure (P = 0.01), neurological failure (P < 0.0001), liver failure (P < 0.0001) and low blood pressure requiring catecholamine support (P = 0.02). The multivariate analysis showed that young age (age less than 5 years), fever > 38.5 degrees C, neurological failure and pulmonary edema were independent factors of severity. Digestive disorders were more frequent in children and in this subgroup diarrhea appeared to be associated with poor outcome. In a subset of patients for whom data were available, fatal cases demonstrated significantly higher liver enzymes levels on admission. CONCLUSION: In Tunisia, gastrointestinal symptoms are often observed in severe scorpion envenomations, especially in young patients. In children, diarrhea and elevated liver enzymes are associated with poor prognosis.     

Prognosis of traumatic head injury in South Tunisia: a multivariate analysis of 437 cases

BACKGROUND: This study aimed to determine predictive factors of mortality after posttraumatic brain injury. METHODS: A retrospective study conducted over a 3-year period (1997-1999) involved 437 adult patients with head injury admitted to the intensive care unit of a university hospital in Sfax, Tunisia. Basic demographic, clinical, biologic, and radiologic data were recorded at admission and during the intensive care unit stay. RESULTS: This study included 393 men (90%) and 44 women with a mean age of 36 +/- 17 years. Traffic accidents were the main cause of trauma (85.6%). In 58% of the cases, the injury was serious (Glasgow Coma Score, <8). The mean simplified acute physiology score was 39 +/- 15, and the mean Injury Severity Score was 34.5 +/- 17. Of the 437 patients, 127 (29.1%) died. According to multivariate analysis, the factors that correlated with a poor prognosis were age older than 40 years (p < 0.01), simplified acute physiology score exceeding 40 (p < 0.001), Glasgow Coma Score lower than 7 (p = 0.03), intracranial mass lesion (p = 0.02), a cerebral herniation (p < 0.001), diabetes insipidus (p < 0.001), and blood sugar level higher than 10 mmol/L (p < 0. 001). CONCLUSIONS: In Tunisia, head injury is a frequent cause of hospitalization, comprising 14.4% of all adult admissions. It is observed most often among young patients involved in traffic accidents. The short-term prognosis is poor, with a high (29%) mortality rate, and determined by demographic, clinical, radiologic, and biologic factors. Prevention is highly advised.     

Spastic paraplegia 15: Linkage and clinical description of three Tunisian families

Hereditary spastic paraplegias (HSP) are a clinically and genetically heterogeneous group of neurodegenerative disorders characterized by slowly progressive spasticity of the lower limbs. The locus designated spastic paraplegia 15 (SPG15), located in a 16‐Mb interval on chromosome 14q, is associated with a rare autosomal recessive complicated form of HSP known as Kjellin's syndrome. In this study, we describe three additional families, of Tunisian origin, linked to the SPG15 locus, one of which had a significant multipoint LOD score of 3.46. In accordance with previous reports, the phenotype of our patients consisted of early onset spastic paraparesis associated with mental impairment and severe progression. Retinal degeneration was not observed, however, but we extended the phenotype of this form to include peripheral neuropathy and white matter abnormalities on MRI. Interestingly, like retinal degeneration, thin corpus callosum is not a constant feature in this entity. © 2007 Movement Disorder Society     

Value of the plasma protein and hemoglobin concentration in the diagnosis of pulmonary edema in scorpion sting patients

OBJECTIVE: To investigate the value of measuring total plasma protein and hemoglobin concentrations for the diagnosis of pulmonary edema secondary to scorpion envenomation. DESIGN AND SETTING: Retrospective study over a 4-year period in the medical intensive care unit of a university hospital. PATIENTS: 67 patients older than 3 years admitted in the intensive care unit for scorpion envenomation and stratified into two groups according to the presence of pulmonary edema assessed by a medical committee that took into account clinical, radiological, and blood gas data at admission and after treatment. Total plasma protein and hemoglobin concentrations were analyzed separately. RESULTS: At admission all patients with and without pulmonary edema exhibited polypnea and tachycardia. The mean plasma protein and hemoglobin concentrations were higher in patients with pulmonary edema (74+/-6 and 14.2+/-2.0 g/dl, respectively) than in those without pulmonary edema (64+/-6 and 12.3+/-1.4 g/dl). After 24 h plasma protein and hemoglobin concentrations decreased in the pulmonary edema group (-11 and -1.9 g/dl) despite a negative fluid balance (-500 ml). A plasma protein concentration of 70 g/l or more predicted the presence of pulmonary edema with a sensitivity of 80% a specificity of 96%, a positive predictive value of 97%, and negative predictive value of 77%. CONCLUSIONS: In scorpion-envenomed patients with cardiorespiratory manifestations high plasma protein and hemoglobin concentrations suggest the presence of pulmonary edema.     

DNA based vaccination with a cocktail of plasmids encoding immunodominant Leishmania (Leishmania) major antigens confers full protection in BALB/c mice

Despite the lack of effective vaccines against parasitic diseases, the prospects of developing a vaccine against leishmaniasis are still high. With this objective, we have tested four DNA based candidate vaccines encoding to immunodominant leishmania antigens (LACKp24, TSA, LmSTI1 and CPa). These candidates have been previously reported as capable of eliciting at least partial protections in the BALB/c mice model of experimental cutaneous leishmaniasis. When tested under similar experimental conditions, all of them were able to induce similar partial protective effects, but none could induce a full protection. In order to improve the level of protection we have explored the approach of DNA based vaccination with different cocktails of plasmids encoding to the different immunodominant Leishmania antigens. A substantial increase of protection was achieved when the cocktail is composed of all of the four antigens; however, no full protection was achieved when mice were challenged with a high dose of parasite in their hind footpad. The full protection was only achieved after a challenge with a low parasitic dose in the dermis of the ear. It was difficult to determine clear protection correlates, other than the mixture of immunogens induced specific Th1 immune responses against each component. Therefore, such an association of antigens increased the number of targeted epitopes by the immune system with the prospects that the responses are at least additive if not synergistic. Even though, any extrapolation of this approach when applied to other animal or human models is rather hazardous, it undoubtedly increases the hopes of developing an effective leishmania vaccine.     

Early results of the Ponseti method using the Steenbek foot abduction brace: a prospective study of 95 feet

The purpose of this study is to evaluate the early results of the Ponseti method and the effectiveness of the Steenbek foot abduction brace. A total of 74 patients with 110 idiopathic clubfeet were included in this prospective study. The feet were evaluated according to the Dimeglio-Bensahel classification, the Catteral-Pirani classification and the functional classification of the Hospital for Joint Diseases. Ninety-eight feet (89%) had a good result after the casting period. All the feet evaluated after the period of full-time bracing and during the period of part-time bracing showed a good correction. The Ponseti method using the Steenbek foot abduction brace is effective in correcting idiopathic clubfeet.