Isolation of chicken taste buds for real‐time Ca2+ imaging

We isolated chicken taste buds and used a real‐time Ca²⁺ imaging technique to investigate the functions of the taste cells. With RT‐PCR, we found that isolated chicken taste bud‐like cell subsets express chicken gustducin messenger RNA. Immunocytochemical techniques revealed that the cell subsets were also immunopositive for chicken gustducin. These results provided strong evidence that the isolated cell subsets contain chicken taste buds. The isolated cell subsets were spindle‐shaped and approximately 61–75 μm wide and 88–98 μm long, and these characteristics are similar to those of sectional chicken taste buds. Using Ca²⁺ imaging, we observed the buds' response to 2 mmol/L quinine hydrochloride (a bitter substance) and their response to a mixture of 25 mmol/L L‐glutamic acid monopotassium salt monohydrate and 1 mmol/L inosine 5′‐monophosphate disodium salt, umami substances. The present study is the first morphological demonstration of isolated chicken taste buds, and our results indicate that the isolated taste buds were intact and functional approaches for examining the taste senses of the chicken using Ca²⁺ imaging can be informative.     

Effect of various potassium‐calcium ratios on cation nutrition of grape grown hydroponically

The effect of potassium (K)‐calcium (Ca) ratios on the cation nutrition of Vitis vinifera L. cv. Négrette was investigated on grafted vines grown hydroponically to gain a deeper insight into the origin of the lack of acidity of some wines. Four nutrient solutions were investigated for long duration experiments: a balanced K‐Ca nutrient solution (K=3.9 meq L^‐1 ; Ca=4.8 meq L^‐1) used as a reference, a low K (K=0.3 meq L^‐1; Ca=8.4 meq L^‐1) and a high K (K=7.1 meq L^‐1; Ca=1.6 meq L^‐1) nutrient solutions. Besides, the reference nutrient solution was enriched with Ca (K=3.9 meq L^‐1; Ca=13.8 meq L^‐1) so as to simulate the possible effects of liming. The experiments showed that, in spite of low K requirements, the high K storage capacity of cultivar Négrette might account for the low acidity of the wines. However, a strong Ca‐K antagonism was characterized: the Ca enrichment of the reference nutrient solution resulted in a 30% decrease in the K concentration of leaf blades and petioles. Liming can thus limit K uptake by the plant and contribute to increased acidity of the wines issued from cultivars grown in acid soils.     

Morphological evaluation of cork oak (Quercus suber): Mediterranean provenance variability in Tunisia

Twenty-six provenances (2 340 plants) of cork oak (Quercus suber spp.) originating from Portugal, Spain, Italy, Morocco, Algeria, and Tunisia were tested for genetic variation among and within provenances by growth traits. Seven morphometrical characters were measured in 90 plants from each provenance. Analysis of variance showed highly significant differences for all characters. The phenotypic coefficient of differentiation reached 0.24 for the form and 0.22 for height, thus revealing a strong structuring between the provenances. Comparative study of growth among the provenances revealed more vigorous growth and better survival rate for those from Morocco, Spain, and Portugal, which may constitute better materials for afforestation. Furthermore, this variability appeared to be geographically structured and would be mainly genetically controlled, as cork oak provenances were cultivated under the same environmental conditions. Our results should be helpful for guide forest managers in afforestation.     

Effects of K-Mg ratio on growth and cation nutrition of Vitis vinifera L. cv. “Dattier de Beiruth” grafted on SO4 rootstock

The area of planting of Vitis vinifera L. cv. “Dattier de Beiruth” (DB) grafted on the SO4 (Selection OPPENHEIM 4) rootstock is significant and constantly growing in Northern Algeria. A hydroponic culture was carried out with DB to investigate the effects of potassium-magnesium (K-Mg) ratio on plant growth and mineral nutrition. Four nutrient solutions were tested on which the K-Mg ratio is variable (nutritive solution (NS)1 = 0.3 K: 3.8 Mg, NS2 = 2.1 K: 2 Mg, NS3 = 2.6 K: 1.5 Mg and NS4 = 3.8 K: 0.3 Mg). The results showed that DB was characterized by a high capacity for K uptake. No significant differences among the treatments were detected in the leaf concentrations of calcium (Ca), however Mg uptake was inhibited by increase of K: Mg in the nutrient solution. Results showed that DB is sensitive to the variation of the cation composition in the nutrient solution. Antagonism between K-Mg was apparent.     

Strain-Specific Behavior of Mycobacterium tuberculosis in Interruption of Autophagy Pathway in Human Alveolar Type II Epithelial A549 Cells

Background:Autophagy induction has been shown to differ in magnitude depending on the mycobacterial species. However, few studies have investigated the specific autophagic capacity of different Mtb strains in ATs. This study aimed to elucidate the host autophagic response to different Mtb strains in ATs responsible for TB in the capital of Iran, Tehran. Methods:A549 cells were infected with three different Mtb clinical isolates (Beijing, NEW1, and CAS1/Delhi) and the reference strain H37Rv. Following RNA extraction, the expression of eight ATG genes, four mycobacterial genes, and three miRNAs was evaluated using quantitative RT-PCR. Results:The results revealed that all four strains influenced the autophagy pathway in various ways at different magnitudes. The Beijing and H37Rv strains could inhibit autophagosome formation, whereas the CAS and NEW1 strains induced autophagosome formation. The expression of genes involved in the fusion of autophagosomes to lysosomes (LAMP1) indicated that all the studied strains impaired the autophagolysosomal fusion; this result is not unexpected as Mtb can block the autophagolysomal fusion. In addition, the Beijing and H37RV strains prevented the formation of autophagic vacuoles, besides mycobacterial targeting of lysosomes and protease activity.Conclusion:This preliminary study improved our understanding of how Mtb manages to overcome the host immune system, such as autophagy, and evaluated the genes used by specific strains during this process. Further studies with a large number of Mtb strains, encompassing the other main Mtb lineages, are inevitable.Key Words: A549 cells, Autophagy, MicroRNA, Mycobacterium tuberculosis     

Non-Linearities between Atmospheric Sulphur and Sulphur Emissions

Downing et al. (1995) and others have reported evidence fora non-linearity between atmospheric sulphur and sulphur emissionsin the U.K. Also, there are reports of the effects of the non-linearity being concentrated in regions close to sources. Here we re-analyse the same data in sulphur dioxide versus emission space. Analysis has been carried out at three sites at varying distances from the main U.K. source regions. Annual, seasonal and meteorological categorisations were made to try andclarify observation of any non-linearity. Over long timescales linearity is not excluded. Inter-annual variability is not correlated with emissions. The relation between sulphur dioxideand emissions was found to be least linear for westerly days at asite in southern Scotland. Overall, the extent of non-linearity is not observed to increase with proximity to sources but the relation is least linear for summer days at sites closer to themain source areas.     

Effects of oral clonidine premedication on haemodynamic response to laryngoscopy and tracheal intubation: a clinical trial

The objective of this study was to evaluate the efficacy of pre-anesthetic orally administration of clonidine on pulse rate and blood stress response to laryngoscopy and tracheal intubation. In a double-blinded, randomized study, 274 ASA I and II subjects with age of 18 to 45 years scheduled for elective surgery under general anesthesia were enrolled. They were randomly allocated to receive oral clonidine (0.2 mg) or placebo as premedication 90-120 min before surgery. All the patients received Succinylcholine (1.5 mg kg(-1)) after induction of anesthesia with Fentanyl (50 microg) and Thiopentone (5 mg kg(-1)). The anesthesia was maintained with halothane (1.5 Mac) in 50% mixture of N2O/O2. Heart rate and systolic blood pressure were recorded before, immediately after and then every 5 min after intubation until 20 min. The Clonidine group showed a significant superiority over placebo in the prevention of increase in systolic blood pressure as well as heart rate over the intubation. A significant difference was observed in both heart rate and systolic blood pressures were significantly higher in Control group at three subsequent measurements following intubation. The results of this study suggest that orally administered clonidine in preanesthetic period, provides more haemodynamic stability and attenuates the stress response to laryngoscopy and intubation.     

The γδ cells as marker of non-seroconverted cattle naturally infected with Mycobacterium avium subspecies paratuberculosis

Early diagnosis of MAP infection is a pressing need to enable efficient intervention with the spread of MAP infection in herds. Hence, study of lymphocyte subsets and their expressed adhesion molecules could contribute in defining a distinct diagnostic marker (or markers) at the subclinical period of the infection that could in turn facilitate the development of effective diagnostic approach. In accordance with this objective, milk and blood samples were collected from two groups of cattle naturally infected with MAP and their corresponding negative controls. Group (C) comprised 3-4 year-old ELISA negative/PCR positive-cattle that were considered as subclinical seronegative low shedder group (early stage). Group (A) included 6-8 year-old ELISA positive-cattle, which were considered as a clinical seropositive group (late stage). Flow cytometry of B cells, CD8⁺, CD4⁺ and γδ cells and the adhesion molecules CD44⁺, CD62L, LFA-1 and LPAM-1 indicated increase in CD4⁺ and B cells levels, with higher levels in blood than milk of group A, and significant expression of CD44⁺ in blood and milk and LPAM-1 in blood only. The CD8⁺ cells count in milk was higher than blood in the late stage. The peculiar feature of the early stage (group C) was the high level of γδ cells in the blood and milk, with tendency to express high level of CD62L. Compelling evidence could support the assumption that the dominant γδ cells at early stage of MAP infection could be of CD8CD2⁻WC+1⁺ phenotype. γδ cells appear as promising markers in defining early changes of MAP infection due to their important role in priming innate and cell mediated immunity. Possible utilization of these peculiar changes in the γδ cells level in the early diagnosis of MAP infection should be the subject of further research.     

Epidemiological, bacteriological and molecular studies on caseous lymphadenitis in Sirohi goats of Rajasthan, India

Corynebacterium pseudotuberculosis is the causative agent of caseous lymphadenitis (CL), a chronic debilitating disease of goats. In the present study, a total of 575 goats of Sirohi breed on an organized farm situated in the semi-arid tropical region of Rajasthan, India were clinically examined. Pus samples from superficial lymph nodes of 27 (4.7%) adult goats presenting clinical lesions suggestive of CL were collected for bacteriological and molecular analyses. Of these goats, 51.9% yielded C. pseudotuberculosis on the basis of morphological, cultural and biochemical characteristics. A polymerase chain reaction (PCR) assay targeting proline iminopeptidase gene specific to C. pseudotuberculosis was developed that confirmed all 14 bacterial isolates. The specificity of the PCR product was confirmed by sequencing of the 551-bp amplicon in both senses, showing 98-100% homology with published sequences. Thus, overall prevalence rate based on clinical, bacterial culture and PCR assay were found to be 4.7%, 2.4% and 2.4%, respectively. The PCR assay developed in this study was found to be specific and rapid, and could be used for confirmation of CL in goats as an alternative method to generally cumbersome, time-consuming and less reliable conventional methods.