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144.
Tra-My N. Duong Thanh-Van Le Khanh-Linh H. Tran Phuong-Tuyen Nguyen Bich-Phuong T. Nguyen Thu-Anh Nguyen Huong-Lan P. Nguyen Bich-Ngoc T. Nguyen Matthew C. Fisher Johanna Rhodes Guy Marks Greg J. Fox Sharon C.-A. Chen Michael G. Walsh Vanessa R. Barrs Jessica Talbot Catriona L. Halliday Tania C. Sorrell Jeremy N. Day Justin Beardsley 《Environmental microbiology》2021,23(12):7632-7642
Azole-resistant environmental Aspergillus fumigatus presents a threat to public health but the extent of this threat in Southeast Asia is poorly described. We conducted environmental surveillance in the Mekong Delta region of Vietnam, collecting air and ground samples across key land-use types, and determined antifungal susceptibilities of Aspergillus section Fumigati (ASF) isolates and azole concentrations in soils. Of 119 ASF isolates, 55% were resistant (or non-wild type) to itraconazole, 65% to posaconazole and 50% to voriconazole. Azole resistance was more frequent in A. fumigatus sensu stricto isolates (95%) than other ASF species (32%). Resistant isolates and agricultural azole residues were overrepresented in samples from cultivated land. cyp51A gene sequence analysis showed 38/56 resistant A. fumigatus sensu stricto isolates carried known resistance mutations, with TR34/L98H most frequent (34/38). 相似文献
145.
Calf thymus DNA containing defined levels of 8-hydroxy-2′-deoxyguanosine (8-oxodG) was prepared by treatment with visible light in the presence of photosensitiser Ro 19-8022. The DNA was checked for stability; after freeze-drying, the amount of 8-oxodG did not increase during 6 weeks' storage at room temperature. However, freeze-drying itself can introduce additional oxidative damage. Two enzymic hydrolysis regimes (DNase I, phosphodiesterases I and II, and alkaline phosphatase; or P1 nuclease and alkaline phosphatase) give similar values for 8-oxodG. 相似文献
146.
R. F. McGregor M. S. Sharon M. Atkinson D. E. Johnson 《Preparative biochemistry & biotechnology》2013,43(6):403-419
The isolation of polyamines from urinary hydrolysates in a sufficiently pure state for subsequent analysis by gas chromatography has proved to be difficult. However, by using columns of Porapak-Q and ion-exchange resins, urinary hydrolysates are readily purified and formation of trifluoroacetyl derivatives of polyamines proceeds in high yield without carryover of artifacts in the gas chromatographic elution profile. Good yields from the trifluoroacetylation reaction are not achieved if large quantities of salts or urinary pigments are present. By obtaining the polyamine carbonates in the final stages of the method described, the trifluoroacetylation reaction yields excellent derivatives of nanogram or microgram amounts, particularly after standing over-night at room temperature. The procedure described in detail should permit routine urinary polyamine analysis where rapidity, ease of handling many samples, freedom from complications and artifacts are a consideration. The recent reports by Russell1, 2 that the urinary excretion of polyamines are greatly elevated in cancer patients has stimulated interest in these compounds as possible biological “markers” for the diagnosis of cancer. The polyamines usually considered are: putrescine, 1, 4-diaminobutane; cadaverine, 1, 5-diaminopentane; spermidine, and spermine. An extensive literature has developed over the last 50 years concerning the isolation and determination of polyamines including many excellent reviews. 3–5 However, the isolation and determination of small quantities of polyamines from biological sources has proven to be difficult. This has led to conflicting conclusions among investigators as to which polyamine is the major excretion product in the urine of cancer patients. 2, 6, 7, 8 The following report presents in detail a new procedure of isolation of urinary polyamines in high yield and pure state that facilitates quantitation of these amines by gas chromatography. 相似文献
147.
Sharon M. Bennett Kelvin K. Ogilvie Jean Paul Roduit 《Nucleosides, nucleotides & nucleic acids》2013,32(1):49-64
Abstract Ethyl dialkylphosphonoacetates were prepared from the corresponding dimethylalkylphosphites via the Arbuzov reaction with ethyl bromoacetate. The phosphonoacetates so produced were converted into enaminoacetates by reaction with DMF dimethylacetal and these were used as bidentate electrophiles for the synthesis of phosphonopyrimidones. Several of these compounds were tested for biological activity but none were found to possess antiviral activity. 相似文献
148.
Crystal H Johnson Brianna L Skinner Sharon M Dietz David Blaney Robyn M Engel George W Lathrop Alex R Hoffmaster Jay E Gee Mindy G Elrod Nathaniel Powell Henry Walke 《Comparative medicine》2013,63(6):528-535
Identification of the select agent Burkholderia pseudomallei in macaques imported into the United States is rare. A purpose-bred, 4.5-y-old pigtail macaque (Macaca nemestrina) imported from Southeast Asia was received from a commercial vendor at our facility in March 2012. After the initial acclimation period of 5 to 7 d, physical examination of the macaque revealed a subcutaneous abscess that surrounded the right stifle joint. The wound was treated and resolved over 3 mo. In August 2012, 2 mo after the stifle joint wound resolved, the macaque exhibited neurologic clinical signs. Postmortem microbiologic analysis revealed that the macaque was infected with B. pseudomallei. This case report describes the clinical evaluation of a B. pseudomallei-infected macaque, management and care of the potentially exposed colony of animals, and protocols established for the animal care staff that worked with the infected macaque and potentially exposed colony. This article also provides relevant information on addressing matters related to regulatory issues and risk management of potentially exposed animals and animal care staff.Abbreviations: CDC, Centers for Disease Control and Prevention; IHA, indirect hemagglutination assay; PEP, postexposure prophylacticBurkholderia pseudomallei, formerly known as Pseudomonas pseudomallei, is a gram-negative, aerobic, bipolar, motile, rod-shaped bacterium. B. pseudomallei infections (melioidosis) can be severe and even fatal in both humans and animals. This environmental saprophyte is endemic to Southeast Asia and northern Australia, but it has also been found in other tropical and subtropical areas of the world.7,22,32,42 The bacterium is usually found in soil and water in endemic areas and is transmitted to humans and animals primarily through percutaneous inoculation, ingestion, or inhalation of a contaminated source.8, 22,28,32,42 Human-to-human, animal-to-animal, and animal-to-human spread are rare.8,32 In December 2012, the National Select Agent Registry designated B. pseudomallei as a Tier 1 overlap select agent.39 Organisms classified as Tier 1 agents present the highest risk of deliberate misuse, with the most significant potential for mass casualties or devastating effects to the economy, critical infrastructure, or public confidence. Select agents with this status have the potential to pose a severe threat to human and animal health or safety or the ability to be used as a biologic weapon.39Melioidosis in humans can be challenging to diagnose and treat because the organism can remain latent for years and is resistant to many antibiotics.12,37,41
B. pseudomallei can survive in phagocytic cells, a phenomenon that may be associated with latent infections.19,38 The incubation period in naturally infected animals ranges from 1 d to many years, but symptoms typically appear 2 to 4 wk after exposure.13,17,35,38 Disease generally presents in 1 of 2 forms: localized infection or septicemia.22 Multiple methods are used to diagnose melioidosis, including immunofluorescence, serology, and PCR analysis, but isolation of the bacteria from blood, urine, sputum, throat swabs, abscesses, skin, or tissue lesions remains the ‘gold standard.’9,22,40,42 The prognosis varies based on presentation, time to diagnosis, initiation of appropriate antimicrobial treatment, and underlying comorbidities.7,28,42 Currently, there is no licensed vaccine to prevent melioidosis.There are several published reports of naturally occurring melioidosis in a variety of nonhuman primates (NHP; 2,10,13,17,25,30,31,35 The first reported case of melioidosis in monkeys was recorded in 1932, and the first published case in a macaque species was in 1966.30 In the United States, there have only been 7 documented cases of NHP with B. pseudomallei infection.2,13,17 All of these cases occurred prior to the classification of B. pseudomallei as a select agent. Clinical signs in NHP range from subclinical or subacute illness to acute septicemia, localized infection, and chronic infection. NHP with melioidosis can be asymptomatic or exhibit clinical signs such as anorexia, wasting, purulent drainage, subcutaneous abscesses, and other soft tissue lesions. Lymphadenitis, lameness, osteomyelitis, paralysis and other CNS signs have also been reported.2,7,10,22,28,32 In comparison, human''s clinical signs range from abscesses, skin ulceration, fever, headache, joint pain, and muscle tenderness to abdominal pain, anorexia, respiratory distress, seizures, and septicemia.7,9,21,22
Open in a separate windowaCountry reflects the location where the animal was housed at the time of diagosis.Here we describe a case of melioidosis diagnosed in a pigtail macaque (Macaca nemestrina) imported into the United States from Indonesia and the implications of the detection of a select agent identified in a laboratory research colony. We also discuss the management and care of the exposed colony, zoonotic concerns regarding the animal care staff that worked with the shipment of macaques, effects on research studies, and the procedures involved in reporting a select agent incident. 相似文献
Table 1.
Summary of reported cases of naturally occurring Burkholderia pseudomalleiinfections in nonhuman primatesCountrya | Imported from | Date reported | Species | Reference |
Australia | Borneo | 1963 | Pongo sp. | 36 |
Brunei | Unknown | 1982 | Orangutan (Pongo pygmaeus) | 33 |
France | 1976 | Hamlyn monkey (Cercopithecus hamlyni) Patas monkey (Erythrocebus patas) | 11 | |
Great Britain | Philippines and Indonesia | 1992 | Cynomolgus monkey (Macaca fascicularis) | 10 |
38 | ||||
Malaysia | Unknown | 1966 | Macaca spp. | 30 |
Unknown | 1968 | Spider monkey (Brachytelis arachnoides) Lar gibbon (Hylobates lar) | 20 | |
Unknown | 1969 | Pig-tailed macaque (Macaca nemestrina) | 35 | |
Unknown | 1984 | Banded leaf monkey (Presbytis melalophos) | 25 | |
Singapore | Unknown | 1995 | Gorillas, gibbon, mandrill, chimpanzee | 43 |
Thailand | Unknown | 2012 | Monkey | 19 |
United States | Thailand | 1970 | Stump-tailed macaque (Macaca arctoides) | 17 |
India | Pig-tailed macaque (Macaca nemestrina) | |||
Africa | Rhesus macaque (Macaca mulatta) Chimpanzee (Pan troglodytes) | |||
Unknown | 1971 | Chimpanzee (Pan troglodytes) | 3 | |
Malaysia | 1981 | Pig-tailed macaque (Macaca nemestrina) | 2 | |
Wild-caught, unknown | 1986 | Rhesus macaque (Macaca mulatta) | 13 | |
Indonesia | 2013 | Pig-tailed macaque (Macaca nemestrina) | Current article |
149.
Legacies of Prehistoric Agricultural Practices Within Plant and Soil Properties Across an Arid Ecosystem 总被引:1,自引:0,他引:1
Sharon J. Hall Jolene Trujillo Dana Nakase Colleen Strawhacker Melissa Kruse-Peeples Hoski Schaafsma John Briggs 《Ecosystems》2013,16(7):1273-1293
Closely integrated research between archaeologists and ecologists provides a long-term view of human land use that is rare in the ecological literature, allowing for investigation of activities that lead to enduring environmental outcomes. This extended temporal perspective is particularly important in aridlands where succession occurs slowly and ecosystem processes are mediated by abiotic, geomorphic factors. Numerous studies show that impacts from ancient human actions can persist, but few have explored the types of practices or mechanisms that lead to either transient or long-term environmental change. We compared plant and soil properties and processes from a range of landscape patch types in the Sonoran Desert of the US Southwest that supported different, well-documented prehistoric farming practices from AD 750–1300. Our results show that the types of ancient human activities that leave long-term ecological legacies in aridlands are those that fundamentally alter “slow variables” such as soil properties that regulate the timing and supply of water. Prehistoric Hohokam floodwater-irrigation practices, but not dryland farming techniques, substantially altered soil texture, which was strongly associated with desert plant community and functional composition. However, prehistoric agriculture did not consistently alter long-term nutrient availability and thus had no impact on “fast variables” such as production of seasonal annual plants that are restricted to periods of ample rainfall. In this arid ecosystem, the inverse texture model explained patterns in plant functional composition at large scales, but is less predictive of production of short-lived desert annuals that experience a more mesic precipitation regime. 相似文献
150.
Craig P Hersh George R Washko Raúl San José Estépar Sharon Lutz Paul J Friedman MeiLan K Han John E Hokanson Philip F Judy David A Lynch Barry J Make Nathaniel Marchetti John D Newell Jr Frank C Sciurba James D Crapo Edwin K Silverman 《Respiratory research》2013,14(1):42