Highly Selective Polypyrrole MIP-Based Gravimetric and Electrochemical Sensors for Picomolar Detection of Glyphosate.

There is a global debate and concern about the use of glyphosate (Gly) as an herbicide. New toxicological studies will determine its use in the future under new strict conditions or its replacement by alternative synthetic or natural herbicides. In this context, we designed biomimetic polymer sensing layers for the selective molecular recognition of Gly. Towards this end, complementary surface acoustic wave (SAW) and electrochemical sensors were functionalized with polypyrrole (PPy)-imprinted polymer for the selective detection of Gly. Their corresponding limits of detection were on the order of 1 pM, which are among the lowest values ever reported in literature. The relevant dissociation constants between PPy and Gly were estimated at [Kd1 = (0.7 ± 0.3) pM and Kd2 = (1.6 ± 1.4) µM] and [Kd1 = (2.4 ± 0.9) pM and Kd2 = (0.3 ± 0.1) µM] for electrochemical and gravimetric measurements, respectively. Quantum chemical calculations permitted to estimate the interaction energy between Gly and PPy film: ΔE = -145 kJ/mol. Selectivity and competitivity tests were investigated with the most common pesticides. This work conclusively shows that gravimetric and electrochemical results indicate that both MIP-based sensors are perfectly able to detect and distinguish glyphosate without any ambiguity.

Screening for deep venous thrombosis after idiopathic scoliosis surgery in children: a pilot study.

BACKGROUND: Venous thrombosis remains an uncommon disorder in childhood. However, the incidence appears to be increasing for a multitude of reasons. The aim of the study was to detect asymptomatic deep venous thrombosis and prothrombotic diseases in nonsyndromic children undergoing scoliosis surgery. METHODS: A prospective study including forty successive teenagers scheduled for posterior spinal fusion. Patients with scoliosis with a history of hemoglobinopathies, cardiac defects, blood clots, early onset osteoporosis, as well as patients with skeletal dysplasias and nonskeletal dysplastic syndromic entities have been excluded. The protocol was designed for active screening of deep venous thrombosis using color Doppler ultrasonography on a day before surgery and repeated on the 3rd, 7th and 15th day postoperatively. Evaluation of prothrombotic disorders included antithrombin and protein C activities, and total protein S antigen level. RESULTS: No patient has manifested clinical symptoms of venous thrombosis in our study. Preoperative Doppler and ultrasound examinations were normal in all patients. Although repeated Doppler ultrasonography demonstrated a transient small clot in two patients. Congenital antithrombin deficiency of 5% has been observed in one child only, without the development of deep venous thrombosis. CONCLUSION: Thromboembolic event seems to be rare after scoliosis surgery. Prophylaxis for venous thrombosis should not be recommended in such patient. But, larger series are required to confirm such results.

Mediastina Tuberculosis mass in a three-month-old boy.

BACKGROUND: Mediastinal mass of tuberculous origin is exceedingly rare in infant. AIM: to report an exceedingly rare case of mediastinal mass of tuberculous origin. CASE REPORT: We report a three-month-old boy who presented a one month history of wheezing and persistent pneumopathy. Radiological investigations showed a large posterior mediastinal mass which infiltrates lungs. Thoracoscopic biopsy showed caseous necrosis with granuloma suggestive of tuberculosis. The outcome was favourable with antituberculous chemotherapy. CONCLUSION: Mediatinal mass of tuberculous origin should considered in differential diagnosis of mediastinal masses in children; be suggested in mediastinal mass in children.

[Congenital hepatic fibrosis in children. Report of 9 cases and review of the literature]. / Fibrose hepatique congenitale chez l'enfant. A propos de 9 cas et revue de la litterature.

Congenital hepatic fibrosis is a recessive autosomic disease with two major risks: gastrointestinal haemorrhage caused by portal hypertension and cholangitis related to bacterial infection of dilated intrahepatic bile ducts.. The aim of our study is to define epidemiological features, the presenting symptoms, the diagnosis, the evolution and the management of this disease. Between January 1990 and December 2000, we reported the cases of nine children with this disease at children hospital of Tunis. Three were male and six female. The mild age was three years and six months. Consanguinity was present in five cases and similar cases were found in six cases. The FHC was revealed by portal hypertension in five cases, angiocholitis in one case and by portal hypertension and angiocholitis in three cases. Liver biopsy was done in seven children. Ultrasound examination of the liver and kidney revealed caroli syndrome in five cases and polykystose renal in two cases The intravenous pyelography was performed in four cases showing precalicial canalicular ectasia in four cases. Eosophageal endoscopy had shown oesophageal varices in six patients. The follow up had shown that three patients had gastrointestinal bleeding, three had angiocholitis. One patient died with multivisceral failure. The treatment of acute bleeding has needed blood transfusion in four cases. Primary prevention of bleeding was done by endoscopic sclerosis alone in one case and associated to betablokers in two cases. Secondary prevention of varices bleeding was done by sclerotherapic in two cases, by beta blokers alone in one case and by betablokers associated to elastic ligation of oesophageal varices in one case.

[The hydatid cyst of the lung in children: 54 cases]. / Le kyste hydatique du poumon chez l'enfant. A propos de 54 cas.

The purpose of this retrospective study is to clarify the clinical, radiological and evolutionary aspects of the hydatid cyst of the lung. Over a period of 9 years (January, 1983 - December, 2001), we brought together in the pediatric service B of Children's hospital of Tunis, 54 cases of hydatid cyst of the lung. The average age is of 7 years 3 months (extremes 2 and 14 years), and the sex- ratio of 1,16. 61% of the children are of rural origin. Bronchpulmonary infection is the most frequent circumstance of discovery (72 % of cases). hemoptysis is revealing in 37% of cases. Discovery is fortuitous in 7% of cases. The radiography of the chest is of a big diagnostic contribution. The radiological aspects obtained are: a homogeneous opaqueness (61%), a diverse opaqueness (26%), an image of lung abscess (22 %), an aspect of floating membrane (4 %), a pleural effusion (9%), and an opaqueness with growing gas (4%). Chest echography was contributory in 77% of cases. 74% of the children were operated without complications. The others were lost.

[Hypertrophic osteoarthropathy revealing a malignant thymoma in a child]. / Osteoarthropathie hypertrophiante revelant un thymome malin chez un enfant. Apport de l'imagerie.

Association of hypertrophic osteoarthropathy and malignant thymoma is very rare in children. Authors report a case of a 14 year old girl followed for rheumatic fever since she was 8 years old. She was explored for arthralgia. The exam showed hippocratic fingers, soft tissues hypertrophy of lower limbs and dyspnoea. Plain radiography had demonstrated symmetrical ossifying periostisis in tubular bones of lower limbs evocating hypertrophic osteoarthropathy diagnosis. Chest radiography has demonstrated bilobate anterior mediastinal mass. Ultrasonography and MRI revealed a voluminous anterior mediastinal mass with cystic and fleshy components. Thymic adenocarcinoma diagnosis was made by surgical biopsy.