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Leopold Fucikovsky Zak*, María de Jesús Yáñez-Morales*, Iobana Alanis-Martínez and Enrique González-Pérez
Abstract: In Mexico in the region of Nopaltepec in Mexico State, the edible Cactus crop, Opuntia ficus-indica is mainly cultivated for prickly pear fruit production. This crop has problems with common pests (insects, mollusks and weeds) which may serve as reservoirs and together with the named Cactus with phytoplasma-like symptoms which through the time inhibit the fruit production, and for this reason, the farmers called these Opuntia plants as Planta Macho (male plant). For molecular identification of the probably involved phytoplasma during 2005 and 2006, 38 samples of Opuntia plant tissues, fruit and some pests were collected for DNA extraction. By direct and nested PCR, 16S rRNA gene was amplified and sequenced. PCR products were analyzed by RFLP with restriction enzymes and in the sequences restriction sites were mapped. Phylogenetic analysis showed that the same phytoplasma was associated with Opuntia crop and its pests (the weeds Argemone mexicana, a grass and Lupinus sp.; a chinch bugs, Chelinidea sp. and the brown garden snail, Helix aspersa). Thus the edible Cactus crop and pests represented novel hosts of Cactus male plant Phytoplasma, and was classified as 16SrI Aster yellows group, of the species Candidatus phytoplasma asteris. This is the first report of this phytoplasma in Mexico and elsewhere.[...] Read More.
Keywords: Argemone, brown garden snail, chinch bugs, edible Cactus, grasses, Lupinus, male plant phytoplasma, Mexico.
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文章
Jafar Khan* and Robeena Farzand
Abstract: The main objective of this study was to find the incidence of urogenital mycoplasma such as Mycoplasma hominis and Ureaplasma urealyticum among patients with history of infertility of unexplained origin and to ascertain their implications in non specific cervicitis and non specific vaginitis. The total number of (n = 337) female patients with history of un- explained vaginitis and cervicitis were screened to observe the prevalence of urogenital mycoplasmas in the disease. Both the high vaginal swabs (HVS) and mid-stream urine were cultured on the liquid media, U-9, and the solid differential mycoplasma agar A-7. The differentiation 0f the implicated organisms were made on the basis of metabolic characteristics of the species. Amongst the total (n = 337) samples, the n = 89 (26.40%) were positive for M. hominis whereas n= 162 (48.07%) isolates determined the U. urealyticum. Upon the outcomes of disease, the cases of non-specific cervicitis yielded the growth of M. hominis and Ureaplasma urealyticum as 32.58% and 59.87% respectively, whereas, among patients of non specific vaginitis, the M. hominis and U. urealyticum were isolated in ratio of 59.55 and 21.60% likewise. From the obtained data in both categories, no solid and direct etiological evidence could be linked to a definite disease outcome of infertility. However, it is certain that these mycoplasmas do cause the urogenital problems as indicated by percents of isolates obtained exclusively. Consequently, after the infection, these organisms could possibly associate for their role in the reproductive failure due to the resulting pathological complications in the urogenital tract of women.[...] Read More.
Keywords: Mycoplasma hominis, Ureaplasma urealyticum, urogenital infections.
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文章
Parisa Keramati, Mehran Hoodaji and Arezoo Tahmourespour*
Abstract: Heavy metals pollution represents an important environmental problem. One of these metals is mercury. The aim of this research was isolating bacteria highly resistant to mercury from dental clinic effluent to investigate their growth potential in the presence of other heavy metals, such as Zn, Cu, Ni, Ag, Cd and Pb. Three dental wastewater samples were selected and their mercury concentrations, pH, EC, BOD5 and COD were determined. The mercury-resistant bacteria were found to belong to the genera of Pseudomonas, Proteus, Citrobacter, Bacillus, Corynebacterium and Staphylococcus. In examining multi-metal resistances, the pattern of hexa-R was seen in the case of Citrobacter and Pseudomonas genera. The highest tolerated concentration of heavy metals was 25.6 mM which is related to Ag and Cu and tolerated by Citrobacter isolate. It is also indicated that Citrobacter was the most resistant isolates to Cd with significant difference (P < 0.05). Results of this study demonstrate the occurrence of different groups of bacteria, capable of high tolerance to mercury with a potential to tolerate a variety of other toxic heavy metals suggest that, resistance to many types of toxicants may be present in the same organism; therefore, such organisms have high potential for biotechnology purposes.[...] Read More.
Keywords: Bacteria, dental effluent, heavy metal, mercury, multi-metal resistance.
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文章
HyoBi Kim, Hyun Baek, SooJin Lee, YangHo Jang, SukChan Jung, Aeran Kim and NongHoon Choe*
Abstract: The objective of this study was to ascertain the nationwide prevalence and antimicrobial resistance rates of Salmonella spp. and Escherichia coli amongst domesticated finisher pigs. Fecal samples (n=840) were collected at 84 slaughterhouses in Korea in May 2009. Salmonella spp. was isolated from 21 of the 840 samples (2.5%), and comprised the following isolated serotypes: Salmonella rissen, Salmonella derby, Salmonella typhimurium. Antimicrobial susceptibility testing was performed for eight antimicrobials. Salmonella resistance was tetracycline (76.19%); nitrofurantoin (38.10%); kanamycin (33.33%); chloramphenicol, sulfamethoxazole/trimethoprim and cephalothin (28.57%); polymyxin B (9.52%); and ampicillin/sulbactam (4.76%), and E. coli resistance was tetracycline (87.11%); chloramphenicol (66.24%); kanamycin (51.68%); sulfamethoxazole/trimethoprim (51.29%); cephalothin (8.38%); nitrofurantoin (5.15%); ampicillin/sulbactam (4.64%); and polymyxin B (0.52%). Tetracycline resistance was most common. Surprisingly, 28.57 and 66.24% of the Salmonella spp. and E. coli isolates, respectively, were resistant to chloramphenicol, which has been banned from agricultural use in Korea for some time. A wide range of strains displayed multi-antimicrobial resistance: 14 out of 21 (66.66%) and 611 out of 776 (78.72%) of the Salmonella and E. coli isolates, respectively. Salmonella spp. and E. coli demonstrate an appreciable broad-spectrum, (multi)-antimicrobial resistance, which is a potential public health concern. A continuous antibiotic surveillance program may be worthwhile.[...] Read More.
Keywords: Swine, pig, Salmonella spp., Escherichia coli, antimicrobial resistance, slaughterhouse.
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Tian Baoming, Sun Dandan, Lian Yuli, Shu Haiyan, Ling Hua, Zang Xin, Wang Bonan and Pei Zhenqiang
Abstract: Oleate- 12 desaturase (FAD2) is a key enzyme involved in the conversion of oleic acid (C18:1) into linoleic acid (C18:2). Brassica napus FAD2 gene was targeted for silencing by its RNAi gene under the control of a seed-specific napin promoter. This study aims to identify the transgenic plants, and analyze the level of BnFAD2 transcripts in addition to fatty acid profile in T3 seeds. As indicated by PCR and southern blotting analysis, a total of six transgenic plants were developed. Analysis performed by RT-PCR revealed the significant down-regulation of BnFAD2 transcripts in developing T3 seeds, which resulted in 13.90 to 32.20% increase of oleic acid composition in mature T 3 seeds. The data demonstrated that BnFAD2 gene was efficiently down-regulated and mediated by its RNAi gene, and oleic acid composition in transgenic rapeseeds was significantly enhanced.[...] Read More.
Keywords: RNAi, oleate-  12 desaturase (FAD2) gene, oleic acid, Brassica napus.
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Khosrow Hazrati Tappe, Habib Mohammadzadeh, Shahla Khashaveh, Baratali Rezapour and Afshin Barazesh*
Abstract: Duplicate stool specimens from 405 primary school attending students of Barandooz-Chay region of Urmia district were tested for intestinal parasites. Besides, duplicate scotch tape slides were obtained and examined microscopically for Enterobius vermicularis and Taenia sp. eggs. A questionnaire containing demographic data was filled for every case, and the relationship between them and the parasitic infection was assayed. Overall, intestinal parasitic prevalence was 42.5%. Prevalence of Giardia lamblia, Entamoeba coli, Blastocystis hominis, Iodamoeba butschlii, Enterobius vermicularis and Hymenolepis nana was 20.5, 14.6, 13.3, 2.5, 10.6 and 0.2%, respectively. No statistic relation was proved between these infections, having tap water facility at home or family population (except for E. vermicularis), but there was a significant relationship between parents’ education level and family population. According to relatively high prevalence of parasitic infections in the study field, it is necessary to increase hygienic and educational measures.[...] Read More.
Keywords: Prevalence, intestinal parasites, primary school, Urmia.
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文章
Abdelhakim Aouf, Yamina Messai, Mohammed S. Salama, Hala M. Aboushady, Mervat G. El-Anany, Souhila Alouache and Rabah Bakour*
Abstract: Seventy six non-typhoid Salmonella were isolated from both human and poultry in Egypt and Algeria and tested for their antibiotics resistance. The incidence of multiple antibiotics resistance was high. To study -lactams resistance mechanisms, double disk synergy test (DDST) with and without cloxacilline was used, results revealed the production of extended spectrum - lactamases (ESBLs) and cephalosporinase in seven and one human Egyptian isolates, respectively. The seven ESBL isolates were identified as Salmonella enterica serotype Poona and their molecular typing by ERIC-PCR revealed unrelated genetic patterns, indicating that these isolates are not clonal. The Cephalosporinase-ESBL- producing isolate was identified as S. enterica serotype Hadar. Polymerase chain reaction (PCR) with specific primers showed the presence of blaTEM and blaSHV genes, respectively, in all and four ESBL producers, and blaAmpC gene was detected in cephalosporinase-producing isolate. Genetic transfer by conjugation and plasmid profiles analysis showed that these genes and their resistance markers were transferable in association with plasmids of 60 kb for ESBLs and 64 and 3.2 kb for AmpC cephalosporinase.[...] Read More.
Keywords: Non-typhoid Salmonella, extended spectrum    -lactamases, cephalosporinase, Egypt, Algeria.
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文章
Fethi Ben Abdallah,*, Ali Ellafi, Rihab Lagha, Héla Kallel and Amina Bakhrouf
Abstract: In this study, we incubated Vibrio parahaemolyticus and Vibrio alginolyticus (marine food-borne pathogens bacteria) in seawater for 8 months to study their morphologic, proteomic and genetic responses to starvation. The atomic force micrographs of stressed strains showed a reduction of the cells size and an evolution to two coccoid-shape forms whose length is less than 0.4 m and between 0.5 and 1 m. Extracellular protein patterns and gelatinase profiles of stressed bacteria were also altered. Indeed, these modifications were manifested by the appearance and/or disappearance of bands as well as in the level of expression of certain proteins. In addition, we also searched for the presence of eight Vibrio cholerae virulence genes: toxR, toxS, toxRS, ctxA, zot, ace, toxT, and Virulence Pathogenicity Island (VPI) in the genome of investigated strains. The expression level of VPI gene studied by reverse transcriptase polymerase chain reaction was decreased, whereas the mRNA quantities of toxR, toxS, and ace in starved Vibrio remained stable.[...] Read More.
Keywords: Vibrio, seawater, alterations, morphology, proteins secreted, virulence gene expression, RT-PCR.
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文章
G. Sharma, R. R. Pandey* and M. S. Singh
Abstract: Fungi play a major role in forest functioning by regulating the process of litter decomposition and nutrient release and are sensitive to management practices. Species richness and abundance of fungi in surface soil and decaying leaf litter of Quercus serrata were compared between a subtropical natural mixed oak forest and a managed oak plantation in the eastern Himalayan region. During 12 months of study a total of 106 fungal species were isolated from soil by dilution plate method and decomposing litter by leaf dilution, washed disk and moist chamber methods. Month of samplings and study sites influenced the species composition of soil and litter fungi. Total species richness of soil fungi was significantly (P < 0.05) lower during different seasons in managed plantation than in the natural forest. Dominant soil colonizers from both sites were: Cladosporium cladosporioides, Clonostachys rosea f. catenulata, Fusarium oxysporum, Penicillium indonesiae, Penicillium turbatum, Trichoderma sp. and Trichoderma koningii. Different soil and litter fungi showed differential seasonal preferences at two study sites. Type of fungal species recovered from leaf litters was influenced by the isolation method. Total number of litter fungi isolated from both sites was broadly similar, whereas the species compositions were different. Litter fungi between the two sites showed the highest similarity index in winter, while the similarity of soil fungi was high during summer. The management practices at plantation site had no significant effect on species richness of litter fungi although soil fungal diversity was significantly reduced indicating the role of intensive management practices on soil fungal population.[...] Read More.
Keywords: Fungal diversity, species richness, soil, litter, natural oak forest, managed plantation, Northeastern India.
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K. Rajagopal, G. Kathiravan* and S. Karthikeyan
Abstract: A phellophytic fungus Phomopsis (Endophytic fungi residing in the Bark) of Azadirachta indica screened for the presence of melanin on their hyphae using an alkali procedure, yielded a dark brown pigment. The purified pigment was subjected to various chemical and physical tests that are diagnostic for melanin. The pigment responds positively for all the diagnostic tests for melanin. Further study on the nature of melanin was done with a bark fungus. The fungus synthesis and deposits DOPA type of melanin on their hyphae.[...] Read More.
Keywords: Coelomycetes, dark pigment, DOPA melanin, kojic acid, endophyte.
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