Isolation and structure determination of natural analogues of the mycotoxin ochratoxin A produced by Aspergillus ochraceus.

Three new natural mycotoxins, analogues of ochratoxin A, in which the phenylalanine moiety is replaced by serine, hydroxyproline or lysine, were isolated from cultures of Aspergillus ochraceus by TLC followed by HPLC column chromatography. Their structures were determined after acidic hydrolysis by the characterisation of both their amino acid moieties and of ochratoxin alpha, the chlorinated dihydroisocoumarin moiety of ochratoxin A. These structures were confirmed by mass spectrum analysis.

[Proximal femoral epiphysis growth after closed reduction for congenital hip dislocation]. / Croissance de la tête fémorale après réduction de la luxation congénitale de la hanche.

PURPOSE OF THE STUDY: This cohort illustrates growth of the center of ossification of the femoral head during and after orthopedic reduction of congenital hip dislocation. MATERIAL AND METHODS: Thirty files of pediatric patients with congenital hip dysplasia were studied retrospectively. Mean age of the children was 24.5 Months. All had unilateral dysplasia, allowing a comparison of femoral head growth by calculating the centers of ossification on the AP views. RESULTS: Mean ratio between the radiological surface of the center of ossification of the femoral head on the dysplastic side and the normal side was about 1: 2. This ratio progressed rapidly during the first Months after reduction and became 1: 1 at a mean 43 Months after reduction. Beyond this time, growth of the femoral heads followed a similar pattern. DISCUSSION: Growth of the center of ossification of the femoral head is related to biomechanical stress forces. Reduction is the only event in the natural history of the disease, but renewed growth of the femoral head cannot provoke in itself normal acetabular growth. Complementary pelvic osteotomy was required for 13 hips. CONCLUSION: Accelerated growth of the femoral head ossification center continues to be a good indicator of femoral head vitality. Early and rapid growth observed after reduction, without osteochondritis, can lead to a normal femoral head at the end of growth.

Correlation between alimentary mycotoxin contamination and specific diseases.

Several pathological cases including primitive hepatomas, Reye's syndrome, alimentary toxic aleukaemia, were encountered in two different Tunisian Sahel hospitals. Contamination of some nutriments of the patients by mycotoxins (aflatoxins, trichothecenes, ochratoxin A, citrinin) are most likely involved in the origin of these diseases.