首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
Background  A 34-year-old, captive-born, vasectomized male chimpanzee ( Pan troglodytes ) presented with lethargy and scrotal swelling.
Methods  Urethral obstruction was diagnosed via urethroscopy.
Results  Removal of the grass stem foreign body resolved the obstruction. Scrotal and preputial ulceration developed from urine scald, which was managed with surgical debridement and antibiotics.
Conclusions  After 7 weeks, the animal was reintroduced to its troup and has been healthy for 11 months.  相似文献   

2.
Aims:  The occurrence of drug resistance and plasmid-mediated transferability was investigated in 15 Aeromonas isolates collected from the ulcers of epizootic ulcerative syndrome (EUS)-affected fishes Katla ( Catla catla ), Mrigel ( Cirrhinus mrigala ) and Punti ( Puntius sp.).
Methods and Results:  Disc diffusion assay showed that all the strains were resistant to ampicillin and sensitive to streptomycin. Of the 15 isolates examined, 93·3% isolates were resistant to erythromycin, sulfadiazine and novobiocin, while 66% were resistant to rifampin and 20% to chloramphenicol. All isolates harboured plasmids with sizes ranging from 64 to 23 kbp with a 23-kbp plasmid in common. Plasmids from 11 Aeromonas strains were transferred to Escherichia coli DH5α recipient strain along with the transfer of ampicillin, erythromycin and chloramphenicol resistance determinants with frequencies ranging from 7·0 × 10−6 to 1·8 × 10−5 transconjugants per recipient cell.
Conclusions:  The resistance to ampicillin, erythromycin, sulfadiazine, novobiocin and chloramphenicol is prevalent among the bacteria isolated from EUS-affected fish, and resistant determinants of some of these antibiotics have been transferred to the bacteria of other origin.
Significance and Impact of the Study:  The emergence of antibiotic resistance bacteria and gene transfer in vitr o suggests that antibiotics should be used more cautiously to treat Aeromonas infections in aquaculture.  相似文献   

3.
Aims:  To evaluate host range and lytic capability of four bacteriophages (rV5, wV7, wV8 and wV11) against Escherichia coli O157:H7 (STEC O157:H7) from cattle and humans.
Methods and Results:  Four hundred and twenty-two STEC O157:H7 isolates (297 bovine; 125 human) were obtained in Alberta, Canada. The four phages were serially diluted and incubated for 5 h with overnight cultures of STEC O157:H7 to estimate their multiplicity of infection (MOI). All bovine STEC O157:H7 were subjected to pulsed-field gel electrophoresis (PFGE) and phage typing (PT). Phage wV7 lysed all human and bovine isolates irrespective of PFGE genotype or PT phenotype and exhibited the lowest MOI (0·004–0·006, P  < 0·0001) of all phages. Phages rV5 and wV11 exhibited a lower MOI (0·002–0·04, P  < 0·0001) than did phage wV8 (25–29) and they had a narrower host range than wV7 or wV8. Phages rV5, wV11 and wV8 lysed 342 (81·0%), 321 (76·1%) and 407 (96·4%), respectively, of the 422 isolates. Susceptibility of bovine STEC O157:H7 to rV5, w11 and wV8 was influenced by PFGE genotype and/or PT phenotype.
Conclusions:  Phages exhibited activity against the majority of bovine and human STEC O157:H7 isolates. PFGE genotype and/or PT phenotype of the host-target influenced their vulnerability to phage attack. Susceptibility of bovine STEC O157:H7 to phage may also differ among farms. Both lytic capability and host range should be considered in the selection of therapeutic phage for on-farm control of STEC O157:H7.
Significance and Impact of the Study:  The present work indicates that a four-phage cocktail should be equally effective at mitigating STEC O157:H7 isolates both of bovine and of human origin. Given that some STEC O157:H7 exhibited resistance to some but not all phages, a phage cocktail is the logical approach to efficacious on-farm therapy.  相似文献   

4.
5.
Aim:  To investigate the potential transfer of Escherichia coli O157:H7 and Salmonella from contaminated manure slurry into the tissue of tall fescue plants.
Methods and Results:  Tall fescue plants ( n  =   50) were fertilized with a manure slurry inoculated with E. coli O157:H7 and Salmonella . Soil was collected and tall fescue plants ( n  =   10 per day) harvested on day 1, 2, 4, 8, and 14 after manure slurry fertilization. Soil samples were positive for E. coli O157:H7 on all days and on day 1, 2, 8, and 14 for Salmonella . None of the plant tissue samples were positive for E. coli O157:H7 on day 1 or 2; however, 20%, 30% and 40% of plant tissue samples were positive for E. coli O157:H7 on day 4, 8, and 14, respectively.
Conclusions:  It may be possible that E. coli O157:H7 can become transmitted and internalized into tall fescue plant tissue within 4 days after exposure to an E. coli O157:H7-contaminated manure slurry. Salmonella did not appear to be transferred to tall fescue plant tissue.
Significance and Impact of the Study:  Faeces contaminated with E. coli O157:11H7 may be one means by which grazing ruminants spread bacterial pathogens to additional animals.  相似文献   

6.
Hedgerows as habitat corridors for forest herbs in central New York, USA   总被引:13,自引:1,他引:12  
1 Samples from 32 hedgerows ( c.  6 m wide, with full-grown trees) in central New York included 39 forest herb taxa, comprising nearly 70% of the forest herb taxa found in adjacent forest samples.
2 We sampled three types of hedgerow. Two types were attached to forest: remnant hedgerows ( n  = 14), and regenerated hedgerows ( n  =  11 ) that had grown up spontaneously between open fields in the last 50 years. There were no significant differences between remnant and regenerated hedgerows in the richness or abundance of forest herbs, presumably indicating colonization of regenerated hedgerows. Such colonization implies that hedgerows serve a corridor function.
3 The species composition of forest herbs in hedgerows attached to forest stands showed a strong affinity with that of the adjacent stand, both for remnant and regenerated hedgerows.
4 There was a distance effect within hedgerows. Richness of forest herbs and similarity of composition to forest declined with distance along the hedgerow from forest, implying colonization from the adjacent attached stand.
5 The third type of hedgerow sampled, isolated remnants ( n  = 7), was not lower in richness or abundance of forest herbs than hedgerows attached to forest.  相似文献   

7.
Background:  Local drug delivery has transformed medicine, yet it remains unclear how drug efficacy depends on physicochemical properties and delivery kinetics. Most therapies seek to prolong release, yet recent studies demonstrate sustained clinical benefit following local bolus endovascular delivery.
Objectives:  The purpose of the current study was to examine interplay between drug dose, diffusion and binding in determining tissue penetration and effect.
Methods:  We introduce a quantitative framework that balances dose, saturable binding and diffusion, and measured the specific binding parameters of drugs to target tissues.
Results:  Model reduction techniques augmented by numerical simulations revealed that impact of saturable binding on drug transport and retention is determined by the magnitude of a binding potential, Bp , ratio of binding capacity to product of equilibrium dissociation constant and accessible tissue volume fraction. At low Bp (< 1), drugs are predominantly free and transport scales linearly with concentration. At high Bp (> 40), drug transport exhibits threshold dependence on applied surface concentration.
Conclusions:  In this paradigm, drugs and antibodies with large Bp penetrate faster and deeper into tissues when presented at high concentrations. Threshold dependence of tissue transport on applied surface concentration of paclitaxel and rapamycin may explain threshold dose dependence of in vivo biological efficacy of these drugs.  相似文献   

8.
Aims:  Bio-process development for isomer selective and efficient production of cis -9, trans -11-octadecadienoic acid (CLA) from trans -vaccenic acid ( t -VA, trans -11-octadecenoic acid) through microbial fatty acid Δ9-desaturation reaction.
Methods and Results:  A total of 550 strains of fungi and yeasts were screened for CLA production from t -VA through Δ9 desaturation. Delacroixia coronata IFO 8586 was selected as a potent producer of CLA from t -VA. Efficient CLA production was observed during cultivation in medium supplemented with the methyl ester of t -VA ( t -VAME). Under the optimal conditions with 33·3 mg ml−1 of t -VAME as substrate, 10·5 mg ml−1 CLA was produced by D. coronata IFO 8586 after 7 days of cultivation in the medium containing dextrin (5·0%), tryptone (2·0%) and thiourea (0·83 μmol ml−1). The strain produced the cis -9, trans -11 isomer of CLA selectively (98% of total CLA), with a small amount of the trans -9, trans -11 isomer (2% of total CLA), mainly in the form of triacylglycerols (69% of total CLA).
Conclusions:  A practical bio-process for selective production of cis -9, trans -11 isomer of CLA using filamentous fungus D. coronata IFO 8586 was successfully established.
Significance and Impact of the Study:  Isomer selective bio-process for the practical production of cis -9, trans -11-CLA was first established. The process is benefitable for expanding the application of CLA for medicinal and nutraceutical purposes.  相似文献   

9.
1 Sedimentary data from a 6-m long core from Kabata Swamp, an in-filled crater in the Ndale volcanic field of western Uganda, provided evidence for a number of cycles of disturbance and recovery of medium altitude forest.
2 The date of formation of the crater was earlier than an Accelerator Mass Spectrometry (AMS) radiocarbon date of 11 460 ± 90  bp (11 699–11 209 bc cal.) and thus appears to predate volcanism farther north in the Fort Portal area.
3 A form of medium altitude forest was already present in western Uganda by the later stages of the last ice age. A more diverse form of medium altitude forest was present from 11 460 ± 90  bp .
4 Some phases of disturbance of this forest during the Holocene could be correlated with established political–economic changes in the study area. One dated c. 2500  bp (768–542 bc cal.) could be associated with the entry of Bantu-speaking people. A second at 400 ± 60  bp ( ad  1419–1648 cal.) coincides with significant shifts in the focus of settlement from drier grassland to wetter, more forested parts.
5 Levels of biodiversity in forests in western Uganda remain relatively high, even after substantial modifications of vegetation cover over an extended period of time. Many central African forest taxa may therefore be able to cope with environmental change, including prolonged human impact.  相似文献   

10.
Background:  In medicine, there is limited knowledge on the toxicity of nanoparticles. In medicine, there has been limited knowledge on the effect of nanoparticles on the white blood cell.
Objective:  To evaluate the effect of gold nanoparticle on the microscopic morphology of white blood cell.
Setting:  Chulalongkorn Univesity, Bangkok, Thailand.
Method:  This study was performed as an experimental study. Mixture of gold nanoparticle solution and blood sample was prepared and analysed.
Result:  This work revealed that after mixing the blood sample with gold nanoparticle solution, accumulation of gold nanoparticle in the white blood cell was observed.
Conclusion:  The effect of gold nanoparticle on the white blood cell can be detected and this knowledge can be used in cytotoxic drug treatment.  相似文献   

11.
Aims:  The aim of the work was to evaluate the circulation of the viruses and to determine a correlation between faecal indicators and viruses.
Methods and Results:  Raw wastewater and effluent samples were collected from three wastewater treatment plants, during three sampling periods, and analysed, using cultural and molecular methods, to determine bacteria and virus presence. The results show a removal of bacterial indicators, but a limited reduction of the phages. The viral analysis displays the circulation of cultivable enteroviruses and differences in the seasonal-geographical distribution. Hepatitis A virus was found with only two genotypes: IA-IB. Rotavirus was present in 11·11%, 24·14%, 2·78% of the samples in the 1st, 2nd and 3rd sampling periods; Astrovirus in 33·33%, 6·9%, 25%; Adenovirus in 7·41%, 3·45%, 2·78%; Norovirus in 7·41%, 10·34%, 5·56% respectively. Adenovirus was never identified in plants B and C as Rotavirus in plant C.
Conclusions:  The presence of faecal indicators was not predictive of the enteric virus presence, whereas a different circulation of Enteroviruses was found in the wastewater treatment plants.
Significance and Impact of the Study:  The study shows the importance and the usefulness of molecular methods to evaluate the virus circulation and the genetic variability of Enteroviruses.  相似文献   

12.
J. Smith 《Cytopathology》2007,18(S1):5-6
1. NHSCSP Annual Review 2006. Patnick J (ed.). Sheffield, UK, NHSCSP; 2007.
2. Dowie R, Stoykova B, Crawford D. et al . Liquid-based cytology can improve efficiency of cervical smear readers: evidence from timing surveys in two NHS cytology laboratories. Cytopathology 2006; 17(2):65–72.
3. Williams AR. Liquid-based cytology and conventional smears compared over two 12-month periods. Cytopathology 2006; 17(2):82–85.
4. Gregory LS, Dudding N, Smith JHF. The impact of introducing liquid based cytology into a routine screening laboratory. Cytopathology 2006; 17(S1):24.
5. Lord Carter of Coles. Report of the Review of NHS Pathology Services in England 2006. Department of Health.
6. Kardos TF. The focal point system: focal point slide profiler and focal point GS. Cancer 2004; 102(6):334–39.
7. Biscotti CV, Dawson AE, Dziura B. et al. Assisted primary screening using the automated ThinPrep Imaging System. Am J Clin Pathol 2005; 123(2):281–87.
8. Eltoum IA, Roberson J. Impact of HPV testing, HPV vaccine development and changing screening frequency on national Pap test volume: projections from the National Health Interview Survey (NHIS). Cancer 2007; 111(1):34–40.
9. Kohli M, Ferko N, Martin A. et al. Estimating the long-term impact of a prophylactic human papillomavirus 16/18 vaccine on the burden of cervical cancer in the UK. Br J Cancer 2007; 96(1):143–50.
10. Franco EL, Cuzick J, Hildesheim A, de Sanjose S. Chapter 20: issues in planning cervical cancer screening in the era of HPV vaccination. Vaccine 2006; 24 (Suppl. 3):S171–S177.
11. Peto J, Gilham C, Fletcher O, Matthews FE. The cervical cancer epidemic that screening has prevented in the UK. Lancet 2004; 364(9430):249–56.  相似文献   

13.
Abstract 1. The ways of using host plants were compared among the three Athalia sawflies [ A. japonica (Klug), A. rosae ruficornis Jakovlev, and A. infumata (Marlatt)] feeding on crucifers in Japan to determine whether host specialisation can explain the difference in their life-history traits. The occurrence of their larvae was examined on each crucifer species in the field, and the suitability of each crucifer species for the three successive steps of host use by the sawflies was evaluated: microhabitat selection by adult females, female oviposition, and larval growth.
2. There were 11 species of crucifer in the study area, and A. japonica , A. rosae , and A. infumata used nine, seven, and eight species respectively. Thus, sawfly host ranges overlapped.
3. Adult females of A. japonica , A. rosae , and A. infumata preferred shady clumps of crucifers, sunny clumps of crucifers, and disturbed areas respectively.
4. Unsuitable hosts for larval performance such as Brassica oleracea and Arabis plants were eliminated from the host ranges of the three sawflies.
5. Once they chose microhabitats, the suitability of each host plant for female oviposition and larval growth was similar.
6. Because of the divergent preferences for microhabitats, the host plants that were suitable for all the three steps were restricted to different sets of plants among the sawflies: Cardamine for A. japonica , cultivated crucifers ( Raphanus and Brassica ) for A. rosae , and Rorippa for A. infumata . These plants could be recognised as the respective primary host plants.
7. The spatio-temporal distributions of primary hosts were consistent with and explained the pattern of diapause and migration of each sawfly, suggesting that host specialisation caused their life-history traits to differentiate.  相似文献   

14.
Aims:  The aim of this study was to investigate the features of rpoB gene mutations associated with Rifampin (RIF) resistance in Mycobacterium tuberculosis ( M. tuberculosis ) in eastern China.
Methods and Results:  The mutations of rpoB gene in 56 clinical isolates of M. tuberculosis resisted to one to four first-line drugs (rifampin, isonicotinyl hydrazide, ethambutol and streptomycin) were analysed by polymerase chain reaction single strand conformation polymorphism analysis (PCR-SSCP) and DNA sequencing. The results of PCR-SSCP showed 52 isolates were positive (existing rpoB mutation) including 47 isolates resisted to RIF. Subsequent results of DNA sequencing showed that 54 isolates had rpoB gene mutation including 49 isolates resisted to RIF. The most frequently mutated sites were at codons 526 (73·2%), 513 (10·7%) and 531 (3·5%).
Conclusions:  The rpoB codon 526 was the most frequently mutated site of RIF-resistant M. tuberculosis strains in eastern China and its frequency is significantly higher ( P  < 0·0001) compared with that in other areas of China and in other geographic regions worldwide.
Significance and Impact of the Study:  Our results reveal that geographic variation is responsible for rpoB mutations in M. tuberculosis and the resulting information will be helpful to improve a novel rapid molecular drug resistance screening approach for MDR TB.  相似文献   

15.
Aims:  A total of nine Listeria monocytogenes strains (seven serotypes) were studied to ascertain whether the non-steroidal anti-inflammatory drug diclofenac (Dc) used in combination with the conventional antilisterial antibiotic gentamicin (Gm) or ampicillin (Am) synergistically augments the efficacy of the antibiotic in vitro .
Methods and Results:  The effect of combination was evaluated by the checkerboard method to obtain a fractional inhibitory concentration (FIC) index followed by kill curves. Dc was synergistic with Gm (FIC 0·37) and there was indifference with Am (FIC 1) against L. monocytogenes ATCC 51774. The magnitude of the differences between killing by a single agent and the combination observed at 24 h was significant ( P  < 0·05) for Dc plus Gm but not Dc plus Am.
Conclusions:  Thus, the ability of extended antibiotic therapy may be improved with the help of this synergistic drug pair in listeriosis.
Significance and Impact of the Study:  Such findings may indicate parallel administration of anti-inflammatory and anti listeriosis drugs.  相似文献   

16.
Aim:  To study the adhesion capability of seven strains of Listeria monocytogenes to polystyrene and stainless steel surfaces after cultivation at various NaCl concentrations.
Methods and Results:  Determination of growth limits indicated that all seven strains were able to grow in up to 11% NaCl in rain heart infusion and 3 g l−1 yeast extract–glucose at 20°C, but no growth was detected at 15% NaCl. Adhesion of L. monocytogenes was estimated after 4-h incubation at 20°C in 96-well microtitre plates. Statistical results revealed no significant difference between adhesion to polystyrene and stainless steel although surface properties were different. Adhesion between 0% and 6% NaCl was not different, whereas adhesion at 11% NaCl was significantly lower. This discrepancy in adhesion was correlated with the down-regulation of flagella at 11% NaCl.
Conclusions:  Only high salinity levels, close to nongrowth conditions, repressed the expression of flagella, and consequently, decreased the adhesion capability of L. monocytogenes .
Significance and Impact of the Study:  Adhesion of L. monocytogenes to inert surfaces depends on environmental conditions that affect flagellum expression. High salinity concentrations would delay biofilm formation.  相似文献   

17.
Abstract.  1. Reproductive cooperation occurs in diverse taxa and a defining characteristic of these social systems is how reproduction is shared. Both male and female burying beetles ( Nicrophorus spp.) facultatively form associations to bury a carcass and rear a single brood, making burying beetles a model system for testing skew theory.
2. In this study, 50% of 40–45 g carcasses and 75% of 55–60 g ones were buried by more than one male and/or female Nicrophorus tomentosus .
3. Females were significantly more likely to cooperate on 55–60 g carcasses than on 40–45 g ones.
4. Analysis of parentage of 13 broods using microsatellite loci as genetic markers showed that maternity analysis of only 2% of the young excluded all females captured leaving the brood chamber after burial. Males previously mated with resident females or displaced by resident males fathered 7% of the young.
5. The male and female remaining the longest were usually the parents of the most offspring, and reproductively dominant individuals also tended to be the largest.
6. Although all but two or three individuals that helped to bury the carcass produced some offspring, reproduction was often not shared equitably. Reproduction of females was significantly skewed on six of nine 40–45 g carcasses but shared fairly equitably on all three 55–60 g ones. Reproduction was skewed among males on 7 of 10 broods.
7. Both males and females relinquished a greater proportion of the brood as the days of assistance from all consexuals increased.  相似文献   

18.
Abstract. 1. Intra-guild predation between early larval instars of two co-existing dragonflies, Sympetrum fonscolombii and Trithemis kirbyi , was investigated with respect to temporal advantage and growth. Three situations were simulated experimentally: (1) Sympetrum fonscolombii began development 11 days before T. kirbyi . (2) Trithemis kirbyi began development 11 days before S. fonscolombii . (3) Both species began on the same day.
2. With a temporal advantage of 11 days to the second species, the resulting larval density of the respective first species was significantly higher than that of the second species.
3. Without a temporal advantage, the survival of S. fonscolombii was higher than that of T. kirbyi , and S. fonscolombii had a larger size due to faster growth than T. kirbyi . Hence, it is assumed that survival depended on early oviposition as well as on larval growth.
4. To test the relevance of the laboratory results, observations at artificial ponds in the Namibian semi-desert were conducted. Trithemis kirbyi was the first species colonising these ponds while S. fonscolombii arrived 15 days later. In field samples, many more Trithemis larvae than Sympetrum larvae were found, a pattern similar to the laboratory experiments in which T. kirbyi enjoyed a temporal advantage.  相似文献   

19.
Aim:  Early identification and characterization of rifampicin-resistant (Rr) Mycobacterium tuberculosis isolates recovered from the samples of tuberculosis (TB) patients in the Aegean (West Anatolian) Region was intended.
Methods and Results:  Sixty isolates [47 (78·3%) multidrug-resistant (MDR)], which were identified as M. tuberculosis complex and phenotypically resistant to rifampicin by both BACTEC mycobacteria growth indicator tube (MGIT) 960 and 460 systems were analysed by a commercial line probe assay (INNO-LiPA Rif TB). The concordance of LiPA with the in vitro susceptibility test was found as 98·3%. Among the isolates, S531L (R5 pattern; 46·7%) and L511P/R, S512T, Q513L/K (ΔS1 pattern; 11·7%) were the most frequent mutation patterns. As compared with the BACTEC systems and conventional techniques for cultivation, identification and in vitro susceptibility testing, INNO-LiPA Rif TB after cultivation in BACTEC MGIT 960 system provided an average of 20 days early diagnosis of Rr M. tuberculosis isolates.
Conclusions:  Rapid molecular identification and characterization of Rr M. tuberculosis isolates after BACTEC MGIT 960 cultivation would be useful for faster diagnosis, infection control and planning of accurate treatment in MDR-TB patients.
Significance and Impact of the Study:  Patients with MDR-TB need a specified treatment and efficient follow-up strategies. Rapid and practical methodologies to diagnose and follow these patients should be applied in routine use.  相似文献   

20.
Aims:  This study investigated the anti-fungal activity of coptisine on Candida albicans growth.
Methods and Results:  The metabolic power-time curves of Candida albicans growth at 37°C affected by coptisine were measured by microcalorimetry using an LKB-2277 Bioactivity Monitor with stop-flow mode. Then, the diameter of inhibitory zones in the agar layer was observed using agar cup method, and the minimal inhibitory concentration (MIC) of coptisine on Candida albicans growth was determined by serial dilution method. From the principal component analysis on nine quantitative parameters obtained from the power-time curves, we could easily evaluate the anti-fungal activity of coptisine by analysing the change of values of the main two parameters, growth rate constant k and maximum power output in the log phase P m, log. The results showed that coptisine had strong anti-fungal activity: at a low concentration (45  μ g ml−1) began to inhibit the growth of Candida albicans and at a high concentration (500  μ g ml−1) completely inhibited Candida albicans growth. Coptisine gave big inhibitory zones with diameters between 11 and 43 mm within test range, and the MIC of it was 1000  μ g ml−1.
Conclusions:  Coptisine had strong anti-fungal activity on Candida albicans growth. The method of microcalorimetry applied for the assay of anti-fungal activity of coptisine was quantitative, sensitive and simple.
Significance and Impact of the Study:  This work will provide useful information for the development of chemical biology policy in the use of anti-microbials in food and drug production.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号