Seasonal variations of physiological responses, milk production, and fatty acid profile of local crossbred cows in Tunisia.

The study investigates the seasonal variations of physiological responses, milk yield, milk composition, and milk fatty acid profile of local crossbred cows (Friesian × Brown Atlas) in northwestern Tunisia. A total of 80 multiparous cows from smallholder farmers were sampled between 2018 and 2019. The cows were feed the same diet ad libitum and exposed to the same Mediterranean climatic conditions. Weekly rectal temperature (RT; °C), respiratory rate (RR; rpm), and heart rate (HR; bpm) were measured per cow in each season. Individual milk yield and samples were recorded bi-weekly and collected in duplicate for chemical analyses. Milk fatty acids (FAs) were analyzed using gas chromatography-mass spectrometry (GC-MS). Results showed an increase (P < 0.05) in RT (+ 1.3%), RR (+ 12.1%), and HR (+ 9.9%) when the temperature-humidity index (THI) increased from winter (53.6) to summer (74.4) in response to heat stress. Milk yield did not vary significantly between seasons (8.3 L/day on average). Summer milk contained more fat (+ 7.8%) and log SCC (+ 13.7%). The proportion of the monounsaturated (31.2 vs. 27.2%) and polyunsaturated (4.29 vs. 3.86%) FAs decreased (P < 0.05) between winter and summer. Saturated FAs (64.5 vs. 67.7%) were higher (P < 0.05) in summer than in winter. Winter milk fat contained higher levels of C18:2cis-9 trans-11 (CLA) (0.73 vs. 0.56%) and ω-3 FA (0.83 vs. 0.63%), but a lower ω-6/ω-3 ratio (4.07 vs. 6.17%) compared to summer. As the cows were fed the same diet throughout the two seasons, the performances obtained were mainly due to the resistance of the local crossbred cow to the hot conditions. It is concluded that the local crossbred cow maintains its productivity and tolerate the hot Mediterranean climate.

Monitoring of dioxin-like, estrogenic and anti-androgenic activities in sediments of the Bizerta lagoon (Tunisia) by means of in vitro cell-based bioassays: contribution of low concentrations of polynuclear aromatic hydrocarbons (PAHs).

We used an array of in vitro cell-based bioassays to assess dioxin-like, estrogenic and (anti-)androgenic activities in organic extracts of sediments from the Bizerta lagoon, one of the largest Tunisian lagoons subjected to various anthropogenic and industrial pressures. The sediments were sampled both in winter and summer 2006 in 6 stations differently impacted and in one reference station located in the seawards entrance of Ghar el Melh lagoon. Chemical analyses of the 16 priority PAHs showed that the sediments were low to moderately contaminated (2-537 ng/g dry weight). By using the estrogen- (MELN) and androgen-responsive (MDA-kb2) reporter cell lines, significant estrogenic and anti-androgenic activities were detected only in the Menzel Bourguiba (MB) site, the most contaminated site, both in winter and summer. By using 7-ethoxyresorufin-O-deethylase (EROD) induction in the fish PLHC-1 cell line after both 4 and 24 h of cell exposure, dioxin-like activities were detected in all analysed samples. Dioxin-like activities were higher after 4 h exposure, and varied according to the sites and the sampling season. While highly significant correlation was observed between bioassay- and chemical analyses-derived toxic equivalents (TEQs), PAHs accounted for only a small part (up to 4%) of the detected biological activities, suggesting that other readily metabolised EROD-inducing compounds were present. This study argues for the use of short time exposure to assess biological TEQs in low contaminated samples and provides new induction equivalent factors (IEF(4h)) for 16 PAHs in the PLHC-1 cell line. Finally, our results stress the need to further characterise the nature of organic chemical contamination as well as its long-term impacts on aquatic wildlife in the Bizerta lagoon.

Kindling and electrode effects on the benzodiazepine receptors density of olfactory bulb and hippocampus after olfactory bulb kindling.

The olfactory bulb (OB) kindling is a model of limbic secondary generalized epilepsy. Ten days after the completion of OB kindling, we have studied the long term effects of both electrode insertion and kindling on the binding of [3H]diazepam to crude mitochondrial fractions. On the one hand, we have shown that electrode implantation in sham-operated controls induced an obvious increase in benzodiazepine (BZD) receptor density (Bmax) only at the site of the electrode in comparison to sham-unoperated rats. These results might indicate an additional mechanism extending earlier observations reported by others, who have shown that prolonged electrode implantation induced changes in sham-operated and kindled rats. On the other hand, the long lasting effect of OB kindling on the binding parameters of [3H]diazepam was examined in the focus and in the hippocampus. The results indicate a bilateral increase of BZD receptors in the OB and an ipsilateral increase in the hippocampus. These changes might be a regulation phenomenon in response to a hyperexcitability state and to focal stimulations.

Sonography in the diagnosis and follow-up of pancreatic pseudocysts in childhood. A report of 4 cases.

Pancreatic cyst disease is rare in children and pseudocysts are in general post traumatic. The authors present four cases of pancreatic pseudocysts in children aged from 2 to 12 years, seen in Institut National de Santé de l'Enfance (Tunis) and in Hôpital Antoine Beclère in Clamart (France). All were verified by surgery. The diagnosis was not established before echography. The authors present the echographic patterns of this rare condition and review the literature. The contribution of the sonographic examination in the diagnosis of the pancreatic cyst in children and in the follow-up of the patients is emphasised.

[Clinical evaluation of flucloxacillin in the treatment of serious staphylococcal infections in children]. / Evaluation clinique de la flucloxacilline dans le traitement des infections staphylococciques graves chez l'enfant.

A total of twenty-nine children were admitted to the paediatric unit with confirmed or presumed staphylococcal infection and subsequently treated with the narrow spectrum antibiotic--flucloxacillin. Despite the gravity of their condition all but two patients made a satisfactory recovery. There were no side-effects associated with this treatment.

[Nasal angiocentric T cell-natural killer cell lymphoma with pancreatic localisation in a child]. / Lymphome N.K./T. nasal angiocentrique avec localisation pancréatique chez un enfant.

The nasal angiocentric T-cell-natural killer cell lymphoma is an aggressive tumor, exceptional in Tunisia, which is observed especially in Asia, Mexico and South America. We report the case of an 11-year-old boy, presenting with an exuberant and ulcerative tumor of the right nasal pit. Radiological investigation evidenced a right ethmoïdo-frontal tumor. Evolution was characterized by the installation of abdominal pain and fever, the evidenciation of a mass within the head of the pancreas that compressed the extra hepatic biliary duct and Wirsung's canal and was associated to hyperamylasemia. Biopsy under ultrasound revealed a histiocytic nature. Nasal biopsy found histiocytic and lymphocytic cells and led to a diagnosis of rhinoscleroma. The absence of improvement under antibiotic treatment and the development of fever with leuconeutropenia oriented towards the diagnosis of a non-Hodgkinian malignant lymphoma. Medullary biopsy and immunohistochimic study confirmed a T/NK cells lymphoma, with medullary invasion. The child died from acute respiratory distress syndrome. The authors insist on the rarity of this bipolar location, in particular in children, emphasize the difficulty of the diagnosis and review the literature.