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101.
Palani Srinivasan Gurusamypalayam Amirthalingam Balasubramaniam Thippichettipalayam Ramasamy Gopala Krishna Murthy Perumal Balachandran 《Asian Pacific Journal of Tropical Biomedicine》2013,3(12):988-994
Objective
To detect the various bacteriological agents and pathological changes in commercial layer chicken affected with egg yolk peritonitis in Namakkal region of India.Methods
A total of 6 572 layer chicken from 85 commercial farms were subjected for the study, out of which 1 715 showed various types of oviduct abnormalities. Among the 1 715, 264 birds from six farms were identified as egg peritonitis on the basis of postmortem examination. Trachea, lung, heart blood, liver, peritoneal exudate, oviduct (infundibulum, magnum, uterus) and cloacal swabs were collected from the 264 birds with egg peritonitis lesion for screening of bacterial agents. Signalment, clinical signs and pathological changes were recorded in the affected flocks.Result
The results of the present investigation indicated that the E. coli associated egg peritonitis was responsible for 15.39% of the reproductive tract abnormalities in commercial layers between 21 and 80 week of age. In the affected flocks egg production drop and mortality varied from 3% to 20% and 0.5% to 7.0% respectively. It was noticed during peak egg production (21 to 60 week) and southwest monsoon season (58%). Statistical analysis of age, season and egg production by Chi square test of independence revealed highly significant difference. E. coli was isolated as a pure culture and concurrent with other bacterial agents in 226 and 38 birds respectively. Among the fifteen E. coli serotypes identified serotype O166, O64 and O111 were predominant. Necropsy examination of affected birds revealed the presence of amorphous or insipissiated yolk material in the abdominal cavity with inflammatory changes in the ovary, oviduct and intestine. Microscopically the oviduct surface epithelium showed degeneration and desquamation, moderate to marked infiltration of inflammatory cells especially heterophils and lymphocytes in various regions and lumen contained serofibrinous exudate, inflammatory and desquamated epithelial cells with bacterial microcolonies. Ovarian follicles revealed hyperemia, degeneration of granulosa cells and infiltration of inflammatory cells. Intestine showed degenerative, necrotic and inflammatory lesion.Conclusion
The findings of this study showed that the egg peritonitis might be caused by either the translocation of intestinal E. coli into the peritoneal cavity or by the movement of cloacal E. coli into the oviduct followed by ascension of these bacteria up the oviduct, through the infundibulum, and into the peritoneal cavity. To control the egg peritonitis faecal contamination with E. coli should be minimized. 相似文献102.
103.
Dinakaran M Senthilkumar P Yogeeswari P China A Nagaraja V Sriram D 《Medicinal chemistry (Shāriqah (United Arab Emirates))》2008,4(5):482-491
Thirty four novel 7-fluoro/nitro-1,2-dihydro-5-oxo-8-(sub)-5H-thiazolo[3,2-a]quinoline-4-carboxylic acids were synthesized from 2,4-dichlorobenzoic acid and 2,4-dichloro-5-fluoroacetophenone by multi step reaction, evaluated for in vitro and in vivo antimycobacterial activities against Mycobacterium tuberculosis H37Rv (MTB), multi-drug resistant Mycobacterium tuberculosis (MDR-TB) and Mycobacterium smegmatis (MC2) and also tested for the ability to inhibit the supercoiling activity of DNA gyrase from M. smegmatis. Among the synthesized compounds, 8-[6-[[(1,1-dimethylethoxy)carbonyl]amino]-3-azabicyclo[3.1.0]hex-3-yl]-1,2-dihydro-7-nitro-5-oxo-5H-thiazolo[3,2-a]quinoline-4-carboxylic acid (10q) was found to be the most active compound in vitro with MIC of 0.08 microM and <0.08 microM against MTB and MDR-TB respectively. Compound 10q was found to be 4.5 and >570 times more potent than isoniazid against MTB and MDR-TB respectively. In the in vivo animal model 10q decreased the bacterial load in lung and spleen tissues with 2.51 and 3.71-log10 protections respectively at the dose of 50 mg/kg body weight. 相似文献
104.
Kochar M Crosatti M Harrison EM Rieck B Chan J Constantinidou C Pallen M Ou HY Rajakumar K 《Antimicrobial agents and chemotherapy》2012,56(4):1845-1853
Since the 2006 discovery of the Acinetobacter baumannii strain AYE AbaR1 resistance island, similar elements have been reported in numerous members of this species. As AbaR1 is distantly related to Tn7, we have renamed it TnAbaR1. TnAbaR transposons are known to carry multiple antibiotic resistance- and efflux-associated genes, although none have been experimentally studied en bloc. We deleted the TnAbaR transposon in A. baumannii A424, which we have designated TnAbaR23, and characterized independent deletion mutants DCO163 and DCO174. The NotI pulsed-field gel electrophoresis (PFGE) profile of strain DCO174 was consistent with targeted deletion of TnAbaR23 alone, but strain DCO163 apparently harbored a second large genomic deletion. Nevertheless, "subtractive amplification" targeting 52 TnAbaR and/or resistance-associated loci yielded identical results for both mutants and highlighted genes lost relative to strain A424. PCR mapping and genome sequencing revealed the entire 48.3-kb sequence of TnAbaR23. Consistent with TnAbaR23 carrying two copies of sul1, both mutants exhibited markedly increased susceptibility to sulfamethoxazole. In contrast, loss of tetAR(A) resulted in only a minor and variable increase in tetracycline susceptibility. Despite not exhibiting a growth handicap, strain DCO163 was more susceptible than strain DCO174 to 9 of 10 antibiotics associated with mutant-to-mutant variation in susceptibility, suggesting impairment of an undefined resistance-associated function. Remarkably, despite all three strains sharing identical gyrA and parC sequences, the ciprofloxacin MIC of DCO174 was >8-fold that of DCO163 and A424, suggesting a possible paradoxical role for TnAbaR23 in promoting sensitivity to ciprofloxacin. This study highlights the importance of experimental scrutiny and challenges the assumption that resistance phenotypes can reliably be predicted from genotypes alone. 相似文献
105.
106.
Chronic hepatitis B virus (HBV) infection is a complex clinical entity frequently associated with cirrhosis and hepatocellular carcinoma (HCC). The persistence of HBV genomes in the absence of detectable surface antigenemia is termed occult HBV infection. Mutations in the surface gene rendering HBsAg undetectable by commercial assays and inhibition of HBV by suppression of viral replication and viral proteins represent two fundamentally different mechanisms that lead to occult HBV infections. The molecular mechanisms underlying occult HBV infections, including recently identified mechanisms associated with the suppression of HBV replication and inhibition of HBV proteins, are reviewed in detail. The availability of highly sensitive molecular methods has led to increased detection of occult HBV infections in various clinical settings. The clinical relevance of occult HBV infection and the utility of appropriate diagnostic methods to detect occult HBV infection are discussed. The need for specific guidelines on the diagnosis and management of occult HBV infection is being increasingly recognized; the aspects of mechanistic studies that warrant further investigation are discussed in the final section. 相似文献
107.
Kanayairam Velayutham Abdul Abdul Rahuman Govindasamy Rajakumar Thirunavukkarasu Santhoshkumar Sampath Marimuthu Chidambaram Jayaseelan Asokan Bagavan Arivarasan Vishnu Kirthi Chinnaperumal Kamaraj Abdul Abduz Zahir Gandhi Elango 《Parasitology research》2012,111(6):2329-2337
The purpose of the present study was based on assessments of the antiparasitic activities of synthesized titanium dioxide nanoparticles (TiO2 NPs) utilizing leaf aqueous extract of Catharanthus roseus against the adults of hematophagous fly, Hippobosca maculata Leach (Diptera: Hippoboscidae), and sheep-biting louse, Bovicola ovis Schrank (Phthiraptera: Trichodectidae). The synthesized TiO2 NPs were analyzed by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and atomic force microscopy (AFM). The formation of the TiO2 NPs synthesized from the XRD spectrum compared with the standard confirmed spectrum of titanium particles formed in the present experiments were in the form of nanocrystals, as evidenced by the peaks at 2?? values of 27.43°, 36.03°, and 54.32°. The FTIR spectra of TiO2 NPs exhibited prominent peaks at 714 (Ti?CO?CO bond), 1,076 (C?CN stretch aliphatic amines), 1,172 (C?CO stretching vibrations in alcoholic groups), 1,642 (N?CH bend bond), and 3,426 (O?CH stretching due to alcoholic group). SEM analysis of the synthesized TiO2 NPs clearly showed the clustered and irregular shapes, mostly aggregated and having the size of 25?C110?nm. By Bragg??s law and Scherrer??s constant, it is proved that the mean size of synthesized TiO2 NPs was 65?nm. The AFM obviously depicts the formation of the rutile and anatase forms in the TiO2 NPs and also, the surface morphology of the particles is uneven due to the presence of some of the aggregates and individual particles. Adulticidal parasitic activity was observed in varying concentrations of aqueous leaf extract of C. roseus, TiO2 solution, and synthesized TiO2 NPs for 24?h. The maximum parasitic activity was observed in aqueous crude leaf extracts of C. roseus against the adults of H. maculata and B. ovis with LD50 values of 36.17 and 30.35?mg/L, and r 2 values of 0.948 and 0.908, respectively. The highest efficacy was reported in 5?mM TiO2 solution against H. maculata and B. ovis (LD50?=?33.40 and 34.74?mg/L; r 2?=?0.786 and 0.873), respectively, and the maximum activity was observed in the synthesized TiO2 NPs against H. maculata and B. ovis with LD50 values of LD50?=?7.09 and 6.56?mg/L, and r 2 values of 0.880 and 0.913, respectively. This method is considered as an innovative alternative approach to control the hematophagous fly and sheep-biting louse. 相似文献
108.
Chinnaperumal Kamaraj Govindasamy Rajakumar Abdul Abdul Rahuman Kanayairam Velayutham Asokan Bagavan Abdul Abduz Zahir Gandhi Elango 《Parasitology research》2012,111(6):2439-2448
With a greater awareness of the hazards associated with the use of synthetic organic insecticides, there has been an urgent need to explore suitable alternative products for pest control. Musca domestica is ubiquitous insect that has the potential to spread a variety of pathogens to humans and livestock. They are mechanical carriers of more than hundred human and animal intestinal diseases and are responsible for protozoan, bacterial, helminthic, and viral infections. The present work aimed to investigate the feeding deterrent activity of synthesized silver nanoparticles (Ag NPs) using leaf aqueous extract of Manilkara zapota against M. domestica. The synthesized Ag NPs were recorded from UV–vis spectrum at 421 nm and scanning electron microscopy confirm the biosynthesis and characterization of Ag NPs with spherical and oval in shape and size of 70–140 nm. The FTIR analysis of the purified nanoparticles showed the presence of bands 1,079, 1,383, 1,627, 2,353, and 2,648 cm?1, which were complete synthesis of AgNPs; the XRD pattern of AgNPs showed diffraction peaks at 2θ values of 38.06°, 44.37°, 64.51°, and 77.31° sets of lattice planes were observed (111), (200), (220), and (311) facts of silver, respectively. Adult flies were exposed to different concentrations of the aqueous extract of synthesized Ag NPs, 1 mM silver nitrate (AgNO3) solution and aqueous extract of M. zapota for 1, 2, and 3 h; however, AgNPs showed 72% mortality in 1 h, 89% mortality was found in 2 h, and 100% mortality was found in 3 h exposure at the concentration of 10 mg/mL and the leaf aqueous extract showed 32% mortality in 1 h, 48% mortality was found in 2 h, and 83% mortality was found in 3 h exposure at concentration of 50 mg/mL. The most efficient activity was observed in synthesized Ag NPs against M. domestica (LD50?=?3.64 mg/mL; LD90?=?7.74 mg/mL), the moderate activity reported in the aqueous extract of M. zapota (LD50?=?28.35 mg/mL; LD90?=?89.19 mg/mL) and nil activity were observed in AgNO3 solution at 3 h exposure time at 10 mg/mL. Dimethyl 2, 2-dichlorovinyl phosphate (DDVP) was used as a positive control and showed the LD50 value of 3.38 mL/L. These results suggest that the synthesized Ag NPs have the potential to be used as an ideal eco-friendly approach for the control of the adult of M. domestica. This method is considered as a new approach to control sanitary pest. Therefore, this study provides first report on the feeding deterrent activity of synthesized Ag NPs against housefly. 相似文献
109.
Draft genome of the red harvester ant Pogonomyrmex barbatus 总被引:3,自引:0,他引:3
Smith CR Smith CD Robertson HM Helmkampf M Zimin A Yandell M Holt C Hu H Abouheif E Benton R Cash E Croset V Currie CR Elhaik E Elsik CG Favé MJ Fernandes V Gibson JD Graur D Gronenberg W Grubbs KJ Hagen DE Viniegra AS Johnson BR Johnson RM Khila A Kim JW Mathis KA Munoz-Torres MC Murphy MC Mustard JA Nakamura R Niehuis O Nigam S Overson RP Placek JE Rajakumar R Reese JT Suen G Tao S Torres CW Tsutsui ND Viljakainen L Wolschin F Gadau J 《Proceedings of the National Academy of Sciences of the United States of America》2011,108(14):5667-5672
We report the draft genome sequence of the red harvester ant, Pogonomyrmex barbatus. The genome was sequenced using 454 pyrosequencing, and the current assembly and annotation were completed in less than 1 y. Analyses of conserved gene groups (more than 1,200 manually annotated genes to date) suggest a high-quality assembly and annotation comparable to recently sequenced insect genomes using Sanger sequencing. The red harvester ant is a model for studying reproductive division of labor, phenotypic plasticity, and sociogenomics. Although the genome of P. barbatus is similar to other sequenced hymenopterans (Apis mellifera and Nasonia vitripennis) in GC content and compositional organization, and possesses a complete CpG methylation toolkit, its predicted genomic CpG content differs markedly from the other hymenopterans. Gene networks involved in generating key differences between the queen and worker castes (e.g., wings and ovaries) show signatures of increased methylation and suggest that ants and bees may have independently co-opted the same gene regulatory mechanisms for reproductive division of labor. Gene family expansions (e.g., 344 functional odorant receptors) and pseudogene accumulation in chemoreception and P450 genes compared with A. mellifera and N. vitripennis are consistent with major life-history changes during the adaptive radiation of Pogonomyrmex spp., perhaps in parallel with the development of the North American deserts. 相似文献
110.
Perumal JS Foo F Cook P Khan O 《Multiple sclerosis (Houndmills, Basingstoke, England)》2012,18(8):1197-1199
Alemtuzumab is an anti-CD52 monoclonal antibody with remarkable efficacy in relapsing multiple sclerosis (MS). In clinical trials and off-label use in MS, alemtuzumab has been administered intravenously (IV). Alemtuzumab is approved for chronic lymphoid leukemia as IV. Oncology guidelines recommend alemtuzumab subcutaneous (SC) over IV. There is no report of alemtuzumab SC in MS. We report two patients with highly active relapsing MS who were treated with SC alemtuzumab, had significant improvement and tolerated SC alemtuzumab well without the typical infusion-associated adverse events. SC alemtuzumab in MS warrants further studies as this may enhance patient convenience and minimize infusion-associated adverse events. 相似文献