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31.

Background

Antimicrobials and anthelmintics are the most commonly used veterinary drugs to control animal diseases. However, widespread use of these drugs could contribute to the emergence of drug resistance. Information on the practice of antimicrobial usage among food animal raising communities in Central Ethiopia is scarce. We used a standardised questionnaire survey to assess knowledge, awareness, and practices related to drug use and resistance in food animals among the farmers in and around Bishoftu town.

Results

Of the total of 220 livestock owners interviewed, around 80% of the respondents were not able to define what antimicrobials are and for what purposes they are used. Only 14.1% (n?=?31) of the respondents had awareness about antimicrobial resistance (AMR) and its consequences; and 35.5% (n?=?11/31) and 9.7% (n?=?3/31) of them agreed that the irrational use of antimicrobials in animals could lead to AMR in animals and humans. Oxytetracycline was the most commonly available antibiotic in veterinary drug shops/pharmacies and the most widely used drug in the area. However, 43.3% of the respondents did not see clinical improvements after using antibiotics. Similarly, the respondents explained that no response was observed in 73.3, 70.8 and 52.5% of the cases after medication with anthelmintics, antiprotozoal and acaricides, respectively. About 56.7% of the respondents considered traditional medicines equally important to modern medicines. It was also noted that there were illegal drug vendors, dispensing medicines under unfavourable conditions which include a direct exposure to sunlight, which practice violates the drug handling and storage recommendations given by WHO.

Conclusion

The study revealed that there is a general lack of awareness among food animal owners about the correct use of antibiotics and anthelmintics. The widespread misuse and improper drug dispensing and handling practices observed in this study can affect the drug quality and can also contribute to the development of drug resistance in central Ethiopia.
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32.
Summary A total of 708 strains belonging to different bacterial genera were isolated from fresh tomatoes, eggs, green peppers and fish sold in open markets in Awassa, Ethiopia. They mainly consisted of coliforms (54%),Staphylococcus aureus (26%) andProteus (16%).Shigella was isolated from 26% of the tomato specimens. Total counts for the various food items varied between 2.4 × 106 c.f.u./g and 9.5 × 106 c.f.u./g. Most probable number of total coliform and faecal coliform ranged from 1.5 × 102/g to 3 × 102/g and 37/g to 70/g. Less than 50% of the isolated 522 Gram-negative rods were susceptible to ampicillin and cephalothin and only 14 isolates were susceptible to all drugs tested.Proteus showed higher rates of resistance to ampicillin, carbenicillin and cephalothin (75%). Resistance to these drugs was also relatively higher inEscherichia coli (50%). Sixty-eight of the 186S. aureus isolates were sensitive to all the drugs tested and susceptibility to tetracycline and chloramphenicol was relatively lower (70%).
Charge microbienne, incidence et résistance aux antibiotiques de quelques micro-organismes dans des aliments destinés à être consommés crus en Ethiopie
Résumé On a isolé un total de 708 souches appartenant à divers genres bactériens de tomates fraîches, d'oeufs, de poivrons verts et de poissons vendus sur les marchés ouverts en Awassa, Ethiopie. Parmi celles-ci, on a trouvé 26% deStaphylococcus aureus et 16% deProteus. On a isolé desShigella dans 26% des tomates testées. L'énumération totale des germes dans divers aliments a donné des valeurs situées entre 2.4 × 106 c.f.u./g et 9.5 × 106 c.f.u./g. Le nombre le plus probable de coliformes totaux et de coliformes fécaux variait entre 1.5 × 102/g et 3 × 102/g et entre 37/g et 70/g. Moins de 50% des 522 souches isolées à forme de bâtonnets étaient sensibles à l'ampicilline et à la céphalothine et seules 14 souches isolées étaient sensibles à toutes les drogues testées. LesProteus ont montré davantage de résistance à l'ampicilline, la carbénicilline et la céphalothine (75%). La résistance à ces drogues était aussi relativement plus élevée chezEscherichia coli. Soixante huit de 186 souches isolées deS. aureus étaient sensibles à toutes les drogues testées et leur sensibilité à la tétracycline et au chloramphenicol était relativement plus faible (70%).
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33.

Purpose

The aim of this study is to develop and test the applicability of a new subcategory assessment method (SAM) for social life cycle assessment using a case study on high-density polyethylene (HDPE) production by Dow Chemical Canada facility in Alberta, Canada.

Methods

The methodology is characterized by six steps: (1) definition of the goal and scope of the assessment; (2) life cycle inventory data collection including context data at country level and company-specific data for foreground processes; (3) impact assessment where the subcategories’ results for foreground processes at company level are evaluated using a new SAM developed and the country social performance in the different subcategories is evaluated using some assessment intervals; (4) comparing the social performance of foreground processes to the social background context in sector or country; (5) evaluating the social performance of background processes using sector performance evaluation from Product Social Impact Life Cycle Assessment (PSILCA) database or country performance evaluation conducted in the study; (6) and discussion and conclusion.

Results and discussion

The method developed was able to identify the subcategories that need high level or some level of improvements along the cradle-to-gate life cycle of HDPE. In addition, the stakeholders with high negative effect were highlighted in every life cycle stage. Through this approach, Dow Chemical Canada is able to prioritize its actions and focus on the areas where its performance is still low compared to its peers in the sector or compared to the situation in the country. Moreover, through using PSILCA database or country performance evaluation to investigate the social performance of background processes, Dow Chemical Canada can determine the social hotspots areas that need more focus from its suppliers.

Conclusions

Applying the new subcategory assessment approach proposed in this study provides an objective way to assess the subcategories while differentiating between two levels of assessment: (1) the commitment to the social subcategory in the company’s policy (defined as cutoff requirement) and (2) the evidence of good/bad practices of the subcategory. In addition, the comparison of performance of the companies in foreground processes to the social background in sector or country has improved the objectivity further.
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34.
The diversity and phylogeny of 32 rhizobial strains isolated from nodules of common bean plants grown on 30 sites in Ethiopia were examined using AFLP fingerprinting and MLSA. Based on cluster analysis of AFLP fingerprints, test strains were grouped into six genomic clusters and six single positions. In a tree built from concatenated sequences of recA, glnII, rpoB and partial 16S rRNA genes, the strains were distributed into seven monophyletic groups. The strains in the groups B, D, E, G1 and G2 could be classified as Rhizobium phaseoli, R. etli, R. giardinii, Agrobacterium tumefaciens complex and A. radiobacter, respectively, whereas the strains in group C appeared to represent a novel species. R. phaseoli, R. etli, and the novel group were the major bean nodulating rhizobia in Ethiopia. The strains in group A were linked to R. leguminosarum species lineages but not resolved. Based on recA, rpoB and 16S rRNA genes sequences analysis, a single test strain was assigned as R. leucaenae. In the nodC tree the strains belonging to the major nodulating groups were clustered into two closely linked clades. They also had almost identical nifH gene sequences. The phylogenies of nodC and nifH genes of the strains belonging to R. leguminosarum, R. phaseoli, R. etli and the putative new species (collectively called R. leguminosarum species complex) were not consistent with the housekeeping genes, suggesting symbiotic genes have a common origin which is different from the core genome of the species and indicative of horizontal gene transfer among these rhizobia.  相似文献   
35.
Epidemiological and experimental evidences have established solar ultraviolet (UV) radiation as the leading cause of skin cancers. Specifically, the frequency of non-melanoma skin cancer, one of the malignancies with the most rapidly increasing incidence, is directly related to the total exposure to solar UV light. As part of a general effort to elucidate the components of cellular signal transduction pathways, the mechanisms of cellular responses to UV radiation have received considerable attention over the last few years. These efforts were driven mainly by the conviction that understanding how normal cells respond to extracellular stimuli such as exposure to UV radiation will undoubtedly help in deciphering what goes wrong in a variety of clinical disorders including skin cancers and will assist in the development of novel therapeutic strategies. Studies over the last decade have established that UV radiation induces a bewildering array of signal transduction pathways, some of which could lead to apoptotic cell death. UV-induced cell death by apoptosis is considered to be a natural protective mechanism that removes damaged keratinocytes and circumvents the risk of malignant transformation. In this review, we summarize some of the most important findings regarding the response and role of mitogen-activated protein kinases in UVA and UVB radiation-induced signaling to apoptosis in keratinocytes. We will also briefly discuss what is known about the role of the BCL-2 family of proteins, the emerging role of lysosomal proteases and other important cytosolic signaling proteins in UV-induced apoptosis.  相似文献   
36.
sn-1 Palmitoyl lysophosphatidylinositol is found in carrot suspension culture cells and can be phosphorylated to [32P]lysophosphatidylinositol monophosphate (LPIP) when [gamma 32P]ATP is added to isolated membranes. Based on in vivo labeling studies, [3H]inositol sn-1 palmitoyl LPIP was found predominantly in the plasma membrane-rich fraction or upper phase isolated by aqueous two-phase partitioning and LPI was found in the intracellular membrane-rich fraction or lower phase (Wheeler and Boss, Plant Physiol. 85, 389-392, 1987). While both membrane fractions phosphorylated LPI in vitro, the apparent Km for LPI in the intracellular membrane fraction was 180 microM and for the plasma membrane was 580 microM. When cells were treated with the ionophore, monensin, the percentage of [3H]inositol LPIP increased in the whole cell lipid extract. However, the monensin treatment decreased the amount of [3H]inositol LPIP and PIP recovered in the plasma membrane fraction relative to the sum of the individual lipid, [3H]inositol LPIP or PIP, respectively, recovered in both membrane fractions.  相似文献   
37.
The genus Cynodon (Gramineae), comprised of 9 species, is geographically widely distributed and genetically diverse. Information on the amounts of molecular genetic variation among and within Cynodon taxa is needed to enhance understanding of phylogenetic relations and facilitate germplasm management and breeding improvement efforts. Genetic relatedness among 62 Cynodon accessions, representing eight species, was assessed using DNA amplification fingerprinting (DAF). Ten 8-mer oligonucleotides were used to amplify specific Cynodon genomic sequences. The DNA amplification products of individual accessions were scored for presence (1) or absence (0) of bands. Similarity matrices were developed and the accessions were grouped by cluster (UPGMA) and principal coordinate analysis. Analyses were conducted within ploidy level (2x = 18 and 4x = 36) and over ploidy levels. Each primer revealed polymorphic loci among accessions within species. Of 539 loci (bands) scored, 496 (92%) were polymorphic. Cynodon arcuatus was clearly separated from other species by numerous monomorphic bands. The strongest species similarities were between C. aethiopicus and C. arcuatus, C. transvaalensis and C. plectostachyus, and C. incompletus and C. nlemfuensis. Intraspecific variation was least for C. aethiopicus, C. arcuatus, and C. transvaalensis, and greatest for C. dactylon. Accessions of like taxonomic classification were generally clustered, except the cosmopolitan C. dactylon var. dactylon and C. dactylon var. afganicus. Within taxa, accessions differing in chromosome number clustered in all instances indicating the 2x and 4x forms to be closely related. Little, if any, relationship was found between relatedness as indicated by the DAF profiles and previous estimates of hybridization potential between the different taxa.  相似文献   
38.
Lepidopteran stem borers are among the most important insect pests of maize, sorghum and sugarcane in sub‐Saharan Africa. Except for Chilo partellus, the other stem borer pests in Ethiopia are indigenous to Africa and are assumed to have coevolved with some native grasses and sedges in the natural habitat. In addition to pest species, natural habitats harbour diverse non‐economic stem borer species, some of which are new to science. However, with the growing threats to natural habitats, some non‐economic stem borer species may switch or expand their host ranges to include cultivated crops and evolve as “new” pests. Besides host switch, some of the unknown species currently limited to natural habitats may disappear. We examined the diversity, abundance and interactions of lepidopteran stem borers and their wild host plants in five different vegetation mosaics in Ethiopia. The stem borer species diversity varied among vegetation mosaics and host plants. Forty‐four stem borer species belonging to 14 different genera in the families of Noctuidae, Crambidae, Pyralidae and Tortricidae were recorded from 34 wild host plants and through light trap. Among these families, Noctuidae was the highest in species richness in which 31 species were identified, out of which 15 species and two genera were new to science. This paper discusses the ecological interpretation of host plant–stem borer species interactions, particularly in relation to habitat disturbances.  相似文献   
39.
Autophagy is a lysosome-dependent degradation system conserved among eukaryotes. The mammalian Atg1 homologues, Unc-51 like kinase (ULK) 1 and 2, are multifunctional proteins with roles in autophagy, neurite outgrowth, and vesicle transport. The mammalian ULK complex involved in autophagy consists of ULK1, ULK2, ATG13, FIP200, and ATG101. We have used pulldown and peptide array overlay assays to study interactions between the ULK complex and six different ATG8 family proteins. Strikingly, in addition to ULK1 and ULK2, ATG13 and FIP200 interacted with human ATG8 proteins, all with strong preference for the GABARAP subfamily. Similarly, yeast and Drosophila Atg1 interacted with their respective Atg8 proteins, demonstrating the evolutionary conservation of the interaction. Use of peptide arrays allowed precise mapping of the functional LIR motifs, and two-dimensional scans of the ULK1 and ATG13 LIR motifs revealed which substitutions that were tolerated. This information, combined with an analysis of known LIR motifs, provides us with a clearer picture of sequence requirements for LIR motifs. In addition to the known requirements of the aromatic and hydrophobic residues of the core motif, we found the interactions to depend strongly on acidic residues surrounding the central core LIR motifs. A preference for either a hydrophobic residue or an acidic residue following the aromatic residue in the LIR motif is also evident. Importantly, the LIR motif is required for starvation-induced association of ULK1 with autophagosomes. Our data suggest that ATG8 proteins act as scaffolds for assembly of the ULK complex at the phagophore.  相似文献   
40.
Local cultivars adapted to specific environmental conditions are the chief source of seed for farmers in Ethiopia and deserve research priority. The aim of this study was, therefore, to determine the genetic relationships between different barley landraces, from north Shewa in Ethiopia so as to differentiate genotypes known by different local names and facilitate their conservation and use in breeding new varieties. Five AFLP primer combinations were analyzed for 19 barley landraces and five malting varieties. The number of scoreable fragments amplified by each AFLP primer combination varied from 49 to 118 with an average of 84.5 and polymorphic fragments for each primer combination varied from 27 to 77 with an average of 58.5. The average percent polymorphism was 69.9% with values ranging from 55.1% to 75.8%. Cluster analysis placed the accessions and malting varieties into one main group while all the farmers’ cultivars, with the exception of two, were in the other main group. It was shown that sampling of germplasm at a given locality might not represent the whole array of genetic variability of locally grown famers’ cultivars. A comprehensive study of all the farmers’ barley cultivars, grown in different parts of Ethiopia, is required to maximize the efforts of germplasm conservation and utilization in national and regional breeding programs.  相似文献   
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