Multicolor and electron microscopic imaging of connexin trafficking     

Gaietta G  Deerinck TJ  Adams SR  Bouwer J  Tour O  Laird DW  Sosinsky GE  Tsien RY  Ellisman MH 《Science (New York, N.Y.)》2002,296(5567):503-507

Recombinant proteins containing tetracysteine tags can be successively labeled in living cells with different colors of biarsenical fluorophores so that older and younger protein molecules can be sharply distinguished by both fluorescence and electron microscopy. Here we used this approach to show that newly synthesized connexin43 was transported predominantly in 100- to 150-nanometer vesicles to the plasma membrane and incorporated at the periphery of existing gap junctions, whereas older connexins were removed from the center of the plaques into pleiomorphic vesicles of widely varying sizes. Selective imaging by correlated optical and electron microscopy of protein molecules of known ages will clarify fundamental processes of protein trafficking in situ.  相似文献   

Effect of improved fallow on crop productivity, soil fertility and climate-forcing gas emissions in semi-arid conditions     

Nicola M. Hall  Bocary Kaya  Jan Dick  Ute Skiba  Amadou Niang  Ramadjita Tabo 《Biology and Fertility of Soils》2006,42(3):224-230

The impacts of fallow on soil fertility, crop production and climate-forcing gas emissions were determined in two contrasting legumes, Gliricidia sepium and Acacia colei, in comparison with traditional unamended fallow and continuous cultivation systems. After 2 years, the amount of foliar material produced did not differ between the two improved fallow species; however, grain yield was significantly elevated by 55% in the first and second cropping season after G. sepium compared with traditional fallow. By contrast, relative to the unamended fallow, a drop in grain yield was observed in the first cropping season after A. colei, followed by no improvement in the second. G. sepium had higher foliar N, K and Mg, while A. colei had lower foliar N but higher lignin and polyphenols. In the third year after fallow improvement, a simulated rainfall experiment was performed on soils to compare efflux of N₂O and CO₂. Improved fallow effects on soil nutrient composition and microbial activity were demonstrated through elevated N₂O and CO₂ efflux from soils in G. sepium fallows compared with other treatments. N₂O emissions were around six times higher from this nitrogen-fixing soil treatment, evolving 69.9 ngN₂O–N g⁻¹soil h⁻¹ after a simulated rainfall event, compared with only 8.5 and 4.8 ngN₂O–N g⁻¹soil h⁻¹ from soil under traditional fallow and continuous cultivation, respectively. The findings indicate that selection of improved fallows for short-term fertility enhancement has implications for regional N₂O emissions for dry land regions.  相似文献   

Prion protein gene polymorphism in four West African sheep populations     

Amadou Traoré  Luis J. Royo  Adama Kaboré  Lucía Pérez-Pardal  Isabel álvarez  Iván Fernández  Laya Sawadogo  Hamidou H. Tamboura  Félix Goyache 《Tropical animal health and production》2012,44(7):1469-1472

A total of 162 individuals, belonging to three Burkinabé and one Niger sheep populations, were analysed for prion protein (PrP) gene polymorphism at codons 136, 154 and 171. The ARQ allele was the most frequent in both the Burkinabé (86.7%) and the Niger (67.5%) sheep populations. The highly sensitive allele VRQ was not found in the sampled individuals. The highly resistant ARR allele was in very low frequency in the Burkina-Sahel (4.4%) and Mossi (3.2%) populations and was not present in the Djallonké and Touareg populations. Only 4 out of 15 possible PrP genotypes were identified in the sampled individuals. No favourable ARR/ARR genotypes were found in either of the breeds. Sequencing a subgroup of the samples allowed the identification of other five polymorphisms on the PrP gene sequence at codons 116, 138, 151, 237 and 240. The very low frequency of the ARR allele in the West African sheep should dissuade the implementation of a preventive selection programme aimed to increase resistance to scrapie, to avoid an extreme erosion of the genetic stock.  相似文献   

Response of Acacia senegal (L.) Willd. to inoculation with arbuscular mycorrhizal fungi isolates in sterilized and unsterilized soils in Senegal     

Fatou Ndoye  Aboubacry Kane  Niokhor Bakhoum  Arsène Sanon  Dioumacor Fall  Diégane Diouf  Samba Ndao Sylla  Amadou Mustapha Bâ  Mame Ourèye Sy  Kandioura Noba 《Agroforestry Systems》2013,87(4):941-952

The benefits of inoculation with six arbuscular mycorrhizal fungi (AMF) isolates (Glomus aggregatum, G. fasciculatum, G. intraradices, G. manihotis, G. mosseae, and G. verriculosum) were investigated on seedlings of Acacia senegal (L.) Willd., a multipurpose tree legume highly valued for arabic gum production. Mycorrhizal root colonization, plant growth and relative mycorrhizal dependency (RMD) were measured in A. senegal seedlings growing in soils from three geographical sites in Senegal (Dahra, Bambey and Goudiry) and two soil conditions (sterilized vs unsterilized) in the glasshouse. The impact of inoculation on mycorrhizal root colonization and plant growth depended on AMF isolates, soil origins and soil conditions. Mycorrhizal root colonization and plant growth were increased in sterilized soils regardless of soil origin and AMF isolates. The degree of RMD of A. senegal seedlings varied with soil origin, soil condition and AMF isolates. A. senegal showed the highest RMD values, reaching a maximum of 45 %, when inoculated with G. manihotis. However, in unsterilized soils, no significant effect of AMF inoculation on plant growth was observed despite significant root colonization with certain AMF isolates in Dahra and Goudiry soils. This indicates that the most infective AMF isolates were not the most effective and unsterilized soils may contain effective mycorrhizal propagules. In conclusion, it is important to consider the native mycorrhizal component of the soils before harnessing mycorrhizal inoculation programs for sustainable agroforestry systems.  相似文献   

Epidemiology and microscopic diagnosis of tuberculosis in pigs and small ruminants slaughtered at Bobo-Dioulasso abattoir,Burkina Faso     

Adama Sanou  Amadou Dicko  Kadiatou R. Sow  Arthur Djibougou  Antoinette Kabore  Bassirou Diarra  Arsne K. Ouedraogo  Dezemon Zingue  Moumini Nouctara  Zekiba Tarnagda 《The Onderstepoort journal of veterinary research》2021,88(1)

Bovine tuberculosis (bTB) is a zoonotic, infectious, chronic and contagious disease, caused by Mycobacterium bovis that mainly affects cattle. This pathology has a negative impact on animals and animal products trade. Unfortunately, in Burkina Faso where agriculture and livestock sectors represent around 80% of the socio-economic activities, the real situation of the disease is not well known especially in small ruminants and swine. Thus, our study focused on both the epidemiology and the microbiological diagnosis of tuberculosis (TB) in small ruminants and pigs slaughtered at Bobo-Dioulasso abattoir. A prospective study was conducted between August 2017 and December 2017. Epidemiological data collection was performed during routine meat inspection; moreover, samples were taken and transported to the Bacteriology laboratory of Centre Muraz for microbiological analyses. This diagnosis consisted in search of Acid Fast Bacilli (AFB) using the hot Ziehl–Neelsen staining. Out of a total of 14 648 small ruminants and 2430 pigs slaughtered during the study period, 156 and 17 had lesions suggestive of bTB with prevalence of 1.07% and 0.7%, respectively. Females and those between 2 and 4 years old were mainly infected. The most affected organs were: lungs, liver, spleen and lymph nodes. Finally, microscopy revealed 43.35% (75/173) of positive cases for AFB. These results confirm the presence of bTB in small ruminants and pigs in Burkina Faso. Efforts must still be made in the fight against this zoonosis in order to limit its economic and public health impacts.  相似文献   

Contrasted optimal environmental windows for both sardinella species in Senegalese waters          下载免费PDF全文

Ousmane Diankha  Aliou Ba  Patrice Brehmer  Timothée Brochier  Bamol Ali Sow  Modou Thiaw  Amadou Thierno Gaye  Fambaye Ngom  Hervé Demarcq 《Fisheries Oceanography》2018,27(4):351-365

We investigate Sardinella aurita and Sardinella maderensis recruitment success relative to the variability of oceanographic conditions in Senegalese waters using generalized additive models (GAM). Results show that recruitment of both species is marked by a strong intra‐annual (seasonal) variation with minimum and maximum in winter and summer, respectively. Their interannual variations are synchronous until 2006 (recruitment decreasing), while from 2007 there is no synchrony. The model developed shows that sardinella recruitment variability is closely related to the tested environmental variables in the study area. However, the key environmental variables influencing the recruitment success are different for both species: the Coastal Upwelling Index and the sea surface temperature for S. aurita and S. maderensis, respectively. We report that recruitment success of S. aurita and S. maderensis are associated with distinct ranges of sea surface temperature, upwelling intensity, wind‐induced turbulence, concentration of chlorophyll‐a and north Atlantic oscillation index. Considering food security and socio‐economic importance of both stocks, we recommend that consideration is given to the environmental variability in the small pelagic fish national management plans, particularly in the context of climate change.  相似文献   

Effects of single and dual inoculation with selected microsymbionts (rhizobia and arbuscular mycorrhizal fungi) on field growth and nitrogen fixation of <Emphasis Type="Italic">Calliandra calothyrsus</Emphasis> Meissn     

Didier Lesueur  Amadou Sarr 《Agroforestry Systems》2008,73(1):37-45

Our study aimed to assess the effect of dual inoculation with the selected Rhizobium strain KWN35 and the arbuscular mycorrhizal isolate BEG 176 (Glomus etunicatum) on the growth of Calliandra calothyrsus cultivated under irrigation in the field in Senegal (Dakar) over a period of 24 months. Although plants inoculated with both microsymbionts grew better (height and root collar diameter) than plants from three other inoculation treatments (control, single inoculation with KWN35 or BEG 176), these results were not statistically different except at 1 and 5 months after field transplantation. KWN35 was present in a relatively high percentage of nodules harvested from plants inoculated with this rhizobial strain either alone or with mycorrhiza (approximately 60% and 40% 1 and 2 years after field transplantation respectively). The percentage of mycorrhizal root infections was around 60% in the inoculated plants after 12 months with significantly higher N, P and K foliar contents of trees compared with the non-inoculated controls. However, as for nodulation, by 24 months after transplantation, there were no significant differences between treatments. We conclude that field inoculation of C. calothyrsus with Rhizobium strain KWN35 and arbuscular mycorrhizal isolate BEG 176 did not have a long-lasting effect on the growth of trees, even when a majority of nodules were occupied by the inoculated rhizobia and the roots infected by the mycorrhiza. Several reasons can be postulated for these results, such as a possible effect of soil fertility on the efficiency of the nodules.  相似文献   

Milk hygiene and udder health in the periurban area of Hamdallaye, Niger   总被引：1，自引：1，他引：0  

A. Harouna  M. Zecchini  C. Locatelli  L. Scaccabarozzi  C. Cattaneo  A. Amadou  V. Bronzo  H. Marichatou  P. J. Boettcher  M. G. Zanoni  L. Alborali  P. Moroni 《Tropical animal health and production》2009,41(5):705-710

The prevalence of intra-mammary infections in dairy herds was studied in Hamdallaye, Niger. A total of 956 milk samples were collected in 2007 from 239 lactating cows of four local breeds in eight traditional herds; the first sampling was undertaken in the dry season at morning milking, and the second in the rainy season at evening milking. Staphylococcus aureus, Coagulase-Negative Staphylococci (CNS) and environmental microorganisms were detected in significantly (p < 0.05) more samples in the rainy season, 55.2%, than in the dry season, 27.1%. Statistically significant (P < 0.05) differences in prevalence were observed among herds and according to lactation number. Infections were assigned to four classes, according to the major pathogen, and the respective mean somatic cell counts during the dry season were: S. aureus, 775 × 10³ cells/ml; CNS, 447 × 10³ cells/ml; environmental microorganisms, 407 × 10³ cells/ml; and non-infected, 262 × 10³ cells/ml. Most of the tested strains were sensitive to antibiotics, and selected strains of S. aureus (n = 15) were negative to the multiplex PCR tests for production of enterotoxins.  相似文献   

Malaria control with genetically manipulated insect vectors     

Alphey L  Beard CB  Billingsley P  Coetzee M  Crisanti A  Curtis C  Eggleston P  Godfray C  Hemingway J  Jacobs-Lorena M  James AA  Kafatos FC  Mukwaya LG  Paton M  Powell JR  Schneider W  Scott TW  Sina B  Sinden R  Sinkins S  Spielman A  Touré Y  Collins FH 《Science (New York, N.Y.)》2002,298(5591):119-121

At a recent workshop, experts discussed the benefits, risks, and research priorities associated with using genetically manipulated insects in the control of vector-borne diseases.  相似文献   

The mosquito genome--a breakthrough for public health     

Morel CM  Touré YT  Dobrokhotov B  Oduola AM 《Science (New York, N.Y.)》2002,298(5591):79

The Anopheles gambiae genome sequence will accelerate identification of new insect vector target genes leading to improved strategies for malaria control.  相似文献