Periodic variation of the water use efficiency in durum wheat.

Water Use Efficiency (WUF) of five durum wheat varieties (Khiar, Karim, Nasr, Razzak and Sobirano) cultivated in Tunisia was investigated. The experiment was conducted under rainfed field conditions, irrigated pots and test tubes at ESA Kef experiment station during the cropping season of 2010-2011. Under rainfed conditions, Khiar has the highest grain yield with 29.35 q ha(-1). Biological WUE ranged from 1.72-1.49 mg dry matter per g of water for Razzak and Nasr, respectively. The WUE of grain ranged.from 0.81-0.48 mg grain per g of water for Khiar and Sobirano, respectively. Biological WUE showed positive correlation to grain yield and stomatal density and negatively correlated with leaf area. Periodic water use efficiency in pot and test tube trials indicated variation of wheat genotypes according to stage periods and how the experiment was conducted. Test tubes trials showed high, accurate and maximum value of water use. Therefore, we can consider that Khiar has a high WUE in the first period; germination-early tillering (6.70 mg dry matter per g water). Nasr and Sobirano valorise well had got water use during the second period; tillering (9.16 and 10.20 mg dry matter per g of water). Razzak shows a high WUE for the third period; booting-early heading (9.06 mg dry matter per g of water). Finally, Karim cultivar has the highest WUE during for the fourth period; heading-physiological maturity (22.13 mg dry matter per g of water). Periods of high WUE can be targeted for appropriate time of wheat cultivar irrigation.

HMGB1, an alarmin promoting HIV dissemination and latency in dendritic cells.

Dendritic cells (DCs) initiate immune responses by transporting antigens and migrating to lymphoid tissues to initiate T-cell responses. DCs are located in the mucosal surfaces that are involved in human immunodeficiency virus (HIV) transmission and they are probably among the earliest targets of HIV-1 infection. DCs have an important role in viral transmission and dissemination, and HIV-1 has evolved different strategies to evade DC antiviral activity. High mobility group box 1 (HMGB1) is a DNA-binding nuclear protein that can act as an alarmin, a danger signal to alert the innate immune system for the initiation of host defense. It is the prototypic damage-associated molecular pattern molecule, and it can be secreted by innate cells, including DCs and natural killer (NK) cells. The fate of DCs is dependent on a cognate interaction with NK cells, which involves HMGB1 expressed at NK-DC synapse. HMGB1 is essential for DC maturation, migration to lymphoid tissues and functional type-1 polarization of naïve T cells. This review highlights the latest advances in our understanding of the impact of HIV on the interactions between HMGB1 and DCs, focusing on the mechanisms of HMGB1-dependent viral dissemination and persistence in DCs, and discussing the consequences on antiviral innate immunity, immune activation and HIV pathogenesis.

Gamma irradiation effects on durum wheat (Triticum durum Desf.) under various conditions.

The effects on morphological and physiological characters of durum wheat (Triticum durum Desf.) plants issued from seeds upon irradiation with low doses of cobalt gamma rays (i.e., 0, 10, 20 and 30 Gy), were studied. The study is carried out in the Experimental Research Station of Ecole Supérieure d'Agriculture du Kef (North West Tunisia) in 2008/2009. In Petri dishes, the 20 Gy dose caused an increase of the speed and Germination Capacity (GC) of the seeds as compared to non irradiated ones. Plants from these treated seeds maintained on Knops' culture medium (culture medium used to study plant growth in test tubes), improved root system in terms of length, volume and weight when compared to the plants issued from the non treated seeds. This irradiation dose (20 Gy) also improved in a significant way the above ground system growth of the plants. Under glass house conditions with a water stress, the plants issued from seeds treated with 20 Gy, had higher water content and membrane stability as compared of those from the non irradiated ones. Furthermore, seed irradiation with this dose had a positive effect on the chlorophyll content and maximum quantum yield of the irradiated plants. These results suggest that ionizing irradiation may be considered as an alternative in improving root growth of the plant and therefore controlling drought.

Studies the effects of low dose of gamma rays on the behaviour of chickpea under various conditions.

In this study, the irradiation effects spring chickpea seeds with low doses (0, 5, 10, 15, 20 and 25 Gy) of radioactive cobalt (60Co) gamma-rays, on the germination characteristics as well as on the root and shoot growth, are investigated. The effects of such irradiation doses on the relative water content and cell membrane stability following a water deficit, are also studied. The irradiated seeds kept their germination speed and capacity in Petri dishes. On Murashige and Skoog (MS) liquid medium, the dose of 15 Gy induced a significant improvement (nearly 20%) in root length as compared with the 0 Gy dose. Under glass house conditions, the root and shoot lengths and dry weights of plants grown from seeds irradiated with a dose of 15 Gy, are found to be improved at rates of 19 and 89%, respectively when compared with plants issued from non-irradiated seeds. The same irradiation dose allowed the plants subjected to a water deficit to maintain a better water level and a more stable cell membrane as compared to the control plants.

[Collagen gastroenterocolitis]. / Une gastroentérocolite collagène.

INTRODUCTION: Collagenous gastroenterocolitis is a recently known rare cause of chronic diarrhoea, that raises numerous nosological and diagnostic problems. OBSERVATION: A 41 year-old woman was hospitalised for severe diarrhoea, diagnosed as collagenous gastroenterocolitis. Gastroscopy and ileocolonoscopy were macroscopically normal, but a 20 to 40 microns thick sub-epithelial collagenous band was revealed in the gastric, duodenal and colic biopsies. Parenteral nutrition and treatment with salazopyrine and prednisolone progressively normalised the transit. Three months later, only a 30 microns colic mucosa collagenous band persisted. All the biopsies taken during control gastro-colonoscopy 2 years later were histologically normal. After 5 years follow-up and absence of treatment, the patient no longer presented diarrhoea or biological abnormality. COMMENTS: This exceptional observation is a reminder that sub-epithelial collagen deposits are not always limited to the colon and therefore justify, in patients with collagenous colitis, systematic gastro-duodenal and ileum biopsies.

[Caruncular site of pyogenic granuloma. Apropos of an anatomo-clinical case]. / Localisation caronculaire d'un granulome pyogénique. A propos d'une observation anatomo-clinique.

A clinico-pathologic case of a pyogenic granuloma is reported in a 34-year-old male patient. Clinically, a nodular painless reddish tumour with a fibrinous membrane covered top, developed at the right caruncle. After surgical excision, the histopathological study established the diagnosis of a pyogenic granuloma, partially covered by a conjunctival epithelium, and a fibrinous membrane at its top.