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1.
Rat bite fever is an under-reported, under-diagnosed emerging zoonosis with worldwide distribution. Besides Spirillum minus, Streptobacillus moniliformis is the major causative microorganism although it usually colonises rats without any clinical signs. A group of house rats (Rattus rattus) kept in a zoo exhibition for educational purposes suffered from neurological signs including disorientation, torticollis, stall walking, ataxia and death. Gross pathological and histo-pathological examinations of the investigated rats revealed high-grade otitis interna et media, from which Streptobacillus notomytis was isolated in pure culture or as the predominant microorganism. This case series underlines a previously expressed hypothesis that R. rattus might be naturally colonised with S. notomytis, whereas the traditional rat bite fever organism, S. moniliformis, might be restricted to the Norway rat (Rattus norvegicus). However, the general paucity of Streptobacillus isolates, especially from their respective animal hosts, precludes definitive proof of these host tropisms. This is the first report of S. notomytis detection outside Asia and Australia and the first evidence for its role as a facultative pathogen in house rats.  相似文献   

2.
The host–parasite–vector relationship of Bartonella spp. system in wild carnivores and their fleas from northwestern Mexico was investigated. Sixty-six carnivores belonging to eight species were sampled, and 285 fleas belonging to three species were collected during spring (April–May) and fall (October–November) seasons. We detected Bartonella species in 7 carnivores (10.6%) and 27 fleas (9.5%) through either blood culture or PCR. Of the 27 Bartonella-positive fleas, twenty-two were Pulex simulans, three were Pulex irritans and one was Echidnophaga gallinacea. The gltA gene and ITS region sequences alignment revealed six and eight genetic variants of Bartonella spp., respectively. These variants were clustered into Bartonella rochalimae, Bartonella vinsonii subsp. berkhoffii and another genotype, which likely represents a novel species of Bartonella spp. Although experimental infection studies are required to prove the vector role of P. simulans, our results suggest that this flea may play an important role in the Bartonella transmission. The results indicated possible host-specific relationships between Bartonella genotypes and the families of the carnivores, but further studies are needed to verify this finding. The presence of zoonotic species of Bartonella spp. in wild carnivores raises the issue of their potential risk for humans in fragmented ecosystems.  相似文献   

3.

Background

Urban rodents and house shrews are closely correlated in terms of location with humans and can transmit many pathogens to them. Hepatitis E has been confirmed to be a zoonotic disease. However, the zoonotic potential of rat HEV is still unclear. The aim of this study was to determine the prevalence and genomic characteristics of hepatitis E virus (HEV) in rodents and house shrews.

Results

We collected a total of 788 animals from four provinces in China. From the 614 collected murine rodents, 20.19% of the liver tissue samples and 45.76% of the fecal samples were positive for HEV. From the 174 house shrews (Suncus murinus), 5.17% fecal samples and 0.57% liver tissue samples were positive for HEV. All of the HEV sequences obtained in this study belonged to Orthohepevirus C1. However, we observed a lower percentage of identity in the ORF3 region upon comparing the amino acid sequences between Rattus norvegicus and Rattus losea. HEV derived from house shrews shared a high percentage of identity with rat HEV. Notably, the first near full-length of the HEV genome from Rattus losea is described in our study, and we also report the first near full-length rat HEV genomes in Rattus norvegicus from China.

Conclusion

HEV is prevalent among the three common species of murine rodents (Rattus. norvegicus, Rattus. tanezumi, and Rattus. losea) in China. HEV sequences detected from house shrews were similar to rat HEV sequences. The high identity of HEV from murine rodents and house shrews suggested that HEV can spread among different animal species.
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4.
More than a dozen Gongylonema spp. (Spirurida: Spiruroidea: Gongylonematidae) have been described from a variety of rodent hosts worldwide. Gongylonema neoplasticum (Fibiger & Ditlevsen, 1914), which dwells in the gastric mucosa of rats such as Rattus norvegicus (Berkenhout) and Rattus rattus (Linnaeus), is currently regarded as a cosmopolitan nematode in accordance with global dispersion of its definitive hosts beyond Asia. To facilitate the reliable specific differentiation of local rodent Gongylonema spp. from the cosmopolitan congener, the genetic characterisation of G. neoplasticum from Asian Rattus spp. in the original endemic area should be considered since the morphological identification of Gongylonema spp. is often difficult due to variations of critical phenotypical characters, e.g. spicule lengths and numbers of caudal papillae. In the present study, morphologically identified G. neoplasticum from 114 rats of seven species from Southeast Asia were selected from archived survey materials from almost 4,500 rodents: Thailand (58 rats), Cambodia (52 rats), Laos (three rats) and Philippines (one rat). In addition, several specimens from four rats in Indonesia were used in the study. Nucleotide sequences of the ribosomal RNA gene (rDNA) (5,649 bp) and the cytochrome c oxidase subunit 1 gene (cox1) (818 bp) were characterised. The rDNA showed little nucleotide variation, including the internal transcribed spacer (ITS) regions. The cox1 showed 24 haplotypes, with up to 15 (1.83%) nucleotide substitutions regardless of parasite origin. Considering that Rattus spp. have been shown to originate from the southern region of Asia and G. neoplasticum is their endogenous parasite, it is reasonable to propose that the present study covers a wide spectrum of the genetic diversity of G. neoplasticum, useful for both the molecular genetic speculation of the species and the molecular genetic differentiation of other local rodent Gongylonema spp. from the cosmopolitan congener.  相似文献   

5.
Natural infection of captive nonhuman primates (NHPs) with Trypanosoma cruzi (agent of Chagas disease) is an increasingly recognized problem in facilities across the southern USA, with negative consequences for NHP health and biomedical research. We explored a central Texas NHP facility as a nidus of transmission by characterizing parasite discrete typing units (DTU) in seropositive rhesus macaques (Macaca mulatta), identifying the wildlife reservoirs, and characterizing vector infection. In seropositive NHPs, we documented low and intermittent concentrations of circulating T. cruzi DNA, with two DTUs in equal proportions, TcI and TcIV. In contrast, consistently high concentrations of T. cruzi DNA were found in wild mesomammals at the facility, yet rodents were PCR-negative. Strong wildlife host associations were found in which raccoons (Procyon lotor) harbored TcIV and opossums (Didelphis virginiana) harbored TcI, while skunks (Mephitis mephitis) were infected with both DTUs. Active and passive vector surveillance yielded three species of triatomines from the facility and in proximity to the NHP enclosures, with 17% T. cruzi infection prevalence. Interventions to protect NHP and human health must focus on interrupting spillover from the robust sylvatic transmission in the surrounding environment.  相似文献   

6.
Ixodes goliath n. sp. (Acari: Ixodidae), is described based on females collected from the eastern hyomys, Hyomys goliath (Milne-Edwards) (Rodentia: Muridae) from Papua New Guinea. Females of I. goliath n. sp. are similar to those of I. priscicollaris Schulze, 1932 but can be distinguished by the overall size, porose areas sculpture and shape of palpal segment I ventrally. For comparative purposes, the female of I. priscicollaris is redescribed. Studied females of I. priscicollaris were found on murid rodents and Phascogale sp. (Dasyuromorphia: Dasyuridae) from Indonesia (Papua Province) and Papua New Guinea.  相似文献   

7.
New materials and previously unpublished data on trematosaurid labyrinthodonts from the Early Triassic Bolshoe Bogdo locality (Astrakhan Region) are described. All cranial trematosaurid specimens from this locality are assigned to the monotypic genus Inflectosaurus based on the postorbital length of the skull roof. The diagnosis of the genus is amended. The intermediate position of Inflectosaurus between Angusaurus and Trematosaurus is marked.  相似文献   

8.
The genetic structure of Sakhalin spruce (Picea glehnii) was studied across the natural range of the species, including two small isolated populations in south Sakhalin and Hayachine, by using six microsatellite loci and maternally inherited mitochondrial gene sequences. We also analyzed P. jezoensis, a sympatric spruce in the range. Genetic diversity of P. glehnii was higher in central Hokkaido and the lowest in the Hayachine. Bayesian clustering and principal coordinate analysis by using the microsatellites indicated that the Hayachine was clearly distinct from other populations, implying that it had undergone strong genetic drift since the last glacial period. P. glehnii harbored four mitochondrial haplotypes, two of which were shared with P. jezoensis. One of the two was observed without geographical concentration, suggesting its derivation from ancestral polymorphism. Another was observed in south Sakhalin and in P. jezoensis across Sakhalin. The Bayesian clustering—by using four microsatellite loci, including P. jezoensis populations—indicated unambiguous species delimitation, but with possible admixture of P. jezoensis genes into P. glehnii in south Sakhalin, where P. glehnii is abundantly overwhelmed by P. jezoensis; this might explain the occurrence of introgression of the haplotype of P. jezoensis into P. glehnii.  相似文献   

9.
Ninety-six methicillin-susceptible Staphylococcus aureus (MSSA) and 11 methicillin-resistant coagulase-negative staphylococci (MRCNS) were recovered from food of animal origin. Multi-drug resistance was detected in 34.1% of isolates. Tetracycline-resistant staphylococci harbored tetK gene (68.8%). Erythromycin/clindamycin-resistant staphylococci carried lnuA/lnuB genes frequently alone or combined with msrA gene. The sec gene was detected in 15.6% of MSSA and two isolates harbored the immune evasion cluster. The spa t337 predominated among MSSA strains. Two ermC-positive MRCNS isolates were observed, five mecA-positive carried SCCmec IVa and 6 were non-typeable by the IWG-SCC classification. These results demonstrate that food of animal origin can be a potential source for spreading of multidrug-resistance gene.  相似文献   

10.
Worldwide, Norway rats (Rattus norvegicus) carry a number of zoonotic pathogens. Many studies have identified rat-level risk factors for pathogen carriage. The objective of this study was to examine associations between abundance, microenvironmental and weather features and Clostridium difficile, antimicrobial-resistant (AMR) Escherichia coli and methicillin-resistant Staphylococcus aureus (MRSA) carriage in urban rats. We assessed city blocks for rat abundance and 48 microenvironmental variables during a trap-removal study, then constructed 32 time-lagged temperature and precipitation variables and fitted multivariable logistic regression models. The odds of C. difficile positivity were significantly lower when mean maximum temperatures were high (≥ 12.89°C) approximately 3 months before rat capture. Alley pavement condition was significantly associated with AMR E. coli. Rats captured when precipitation was low (< 49.40 mm) in the 15 days before capture and those from blocks that contained food gardens and institutions had increased odds of testing positive for MRSA. Different factors were associated with each pathogen, which may reflect varying pathogen ecology including exposure and environmental survival. This study adds to the understanding of how the microenvironment and weather impacts the epidemiology and ecology of zoonotic pathogens in urban ecosystems, which may be useful for surveillance and control activities.  相似文献   

11.
Ammonoids from the basal beds of the Nerpalakh Formation (Lower Frasnian) of Belkovsky Island (New Siberian Archipelago) are systematically studied. Taxonomically, the assemblage studied (Manticoceras insulare sp. nov., Tornoceras typum (Sandberger, 1851), and T. contractum Glenister, 1958) is similar to the Early Frasnian ammonoid assemblage of South Timan, from which its is distinguished by the absence of the genera Timanites and Komioceras. The same beds contain conodonts of the Palmatolepis transitans Zone (= MN 4 Zone of the Montagne Noire standard succession), which allow the correlation of the beds studied with the Timanites keyserlingi and Komioceras stuckenbergi ammonoid zones of South Timan. The Early Frasnian ammonoids could supposedly have entered the region of the New Siberian Archipelago from the southwest at the time of a major transgression, which facilitated the distribution of the genera Manticoceras and Tornoceras. A new species of the genus Manticoceras is described.  相似文献   

12.
Populations of the Australian redback spider, Latrodectus hasseltii Thorell 1870, were first recorded in New Zealand in the early 1980s and in Osaka, Japan in 1995. Reliable records suggest that naturalised populations of L. hasseltii in New Zealand are present only in Central Otago and New Plymouth. In Central Otago, L. hasseltii feeds on endangered invertebrates, such as Prodontria modesta (Broun 1909). Latrodectus hasseltii is also a hazard to the New Zealand endemic L. katipo through interbreeding and competitive displacement. CLIMEXTM was used to model the potential global distribution of L. hasseltii based on current climate, and using ArcGIS® 9.2, areas of suitable climate in New Zealand were overlaid with favourable habitats to identify areas most suitable for L. hasseltii establishment. In addition, shelter that urban areas offer L. hasseltii were modelled in CLIMEX and incorporated into ArcGIS to produce maps indicating cities and built up areas where the species could establish. The presence of L. hasseltii in New Zealand and Japan, and its possible spread to other areas, is of human health significance, and the species may also impact on native biodiversity.  相似文献   

13.
Rodent species were assessed as potential hosts of Trypanosoma cruzi, the etiologic agent of Chagas disease, from five sites throughout Texas in sylvan and disturbed habitats. A total of 592 rodents were captured, resulting in a wide taxonomic representation of 11 genera and 15 species. Heart samples of 543 individuals were successfully analyzed by SybrGreen-based quantitative PCR (qPCR) targeting a 166 bp fragment of satellite DNA of T. cruzi. Eight rodents representing six species from six genera and two families were infected with T. cruzi. This is the first report of T. cruzi in the pygmy mouse (Baiomys taylori) and the white-footed mouse (Peromyscus leucopus) for the USA. All infected rodents were from the southernmost site (Las Palomas Wildlife Management Area). No differences in pathogen prevalence existed between disturbed habitats (5 of 131 tested; 3.8%) and sylvan habitats (3 of 40 tested; 7.5%). Most positives (n = 6, 16% prevalence) were detected in late winter with single positives in both spring (3% prevalence) and fall (1% prevalence). Additionally, 30 Triatoma insects were collected opportunistically from sites in central Texas. Fifty percent of these insects, i.e., 13 T. gerstaeckeri (68%), and two T. lecticularia (100%) were positive for T. cruzi. Comparative sequence analyses of 18S rRNA of samples provided identical results with respect to detection of the presence or absence of T. cruzi and assigned T. cruzi from rodents collected in late winter to lineage TcI. T. cruzi from Triatoma sp. and rodents from subsequent collections in spring and fall were different, however, and could not be assigned to other lineages with certainty.  相似文献   

14.
The Botrychium lunaria (Ophioglossaceae) complex worldwide includes the named species B. lunaria, B. crenulatum, B. tunux, and B. yaaxudakeit. These species have been distinguished from each other morphologically and genetically. This study further investigates the genetic diversity and geographic distribution of this complex, examining a large number of plants worldwide. Enzyme electrophoresis was used to examine allelic variation of 22 loci for 1574 plants of putative B. lunaria, B. crenulatum and B. tunux from North America, Eurasia, and New Zealand, and B. dusenii from the Falkland Islands. Variation in allelic composition assessed by genetic identity and cluster analysis using the programs PopGene and STRUCTURE as well as morphology and geography indicated that the complex is composed of six distinct entities; two of which warrant recognition as new species, B. neolunaria, endemic to North America, and B. nordicum, sister to the B. lunaria complex, from Iceland and Norway; and a new combination, B. lunaria var. melzeri , endemic to Greenland, Iceland, and Norway. The new taxa are described in this paper. Three entities within B. tunux are discussed but not proposed for recognition at this time. Botrychium lanceolatum, included in this study, is composed of three morphologically and genetically distinct entities warranting taxonomic recognition.  相似文献   

15.
16.
The results of the body-surface infrared thermography of rodents of the genus Lophuromys suggest that heat insulation of the black-clawed brush-furred rat L. melanonyx, a large specialized species of the AfroAlpine zone, is worse than that of the related smaller species, the golden-footed (L. chrysopus) and shorttailed (L. brevicaudus) brush-furred rats, that inhabit tropical forest and Erica shrub, respectively. A decrease in heat insulation of the alpine species may facilitate the use of solar radiation for supporting heat balance of these diurnal animals.  相似文献   

17.
The availability of sufficient irrigation water and the development of drought-tolerant species are challenging factors in the design and maintenance of green roofs in modern cities. Green roof plants of Petunia hybrid Headliner® Red Star, Ageratum hybrid Artist® blue, and Mentha spicata L. grown in a simulated green roof pot system under controlled greenhouse conditions. The plants were watered every 2 or 6 days (2DWI/6DWI) for 8 weeks accompanied by either a 6-day treatment of seaweed extracts of Ascophyllum nodosum as a soil drench or foliar spray, or two concentrations of trinexapac-ethyl (TE) biweekly sprays. Following treatments, leaf number, leaf area, dry weights, plant height, stomatal conductanse, photosynthetic and transpiration rates and leaf water potential and relative water content were determined in two seasons during 2016 and 2017. The prolonged irrigation intervals reduced plant growth as revealed by morphological and physiological parameters. The application of SWE as drench treatment improved Petunia and Ageratum plant vegetative growth, stomatal conductance, photosynthetic and transpiration rates and leaf water potential and relative water content during prolonged irrigation intervals. TE increased the vegetative growth as well as the physiological performance of Ageratum plants. However, neither SWE nor TE treatments improved the performance of Mentha plants under prolonged irrigation intervals. It was suggested that improved photosynthetic rates were stimulated by enhanced stomatal conductance leading to improved leaf water potential as well as increased relative water content during prolonged irrigation conditions.  相似文献   

18.
Steady growth in the degree of antimicrobial resistance in Neisseria gonorrhoeae calls for the control of the spreading of resistance mutations. Here we present the data describing drug resistance mutations, the results of antimicrobial susceptibility tests, and molecular genotypes of 128 recent N. gonorrhoeae isolates collected across 9 regions of the Russian Federation. The mutations in chromosome genes penA, ponA, rpsJ, gyrA, parC, which determine the susceptibility of N. gonorrhoeae to penicillins, tetracyclines, and fluoroquinolones were detected by multiplex amplification followed by hybridization on a hydrogel microarray. The most frequent mutation was an insertion of an aspartate at position 345 of penA gene (76.6%), whereas mutations Leu421Pro in ponA gene, Val57Met in rpsJ gene, Ser91Phe in gyrA gene, Asp95Gly in gyrA gene, and Ser87Arg in parC gene were detected in 32.8–36.7% of strains. One third of studied N. gonorrhoeae isolates harbored multiple drug resistance mutations in bacterial chromosome, resulting in the bimodal distribution of mutation profiles and related patterns of antimicrobial susceptibility. The spread of multiple resistance could be explained by the vertical transfer of the mutations resulting in the clonality of the N. gonorrhoeae population.  相似文献   

19.
Conventional wisdom states Cannabis sativa originated in Asia and its dispersal to Europe depended upon human transport. Various Neolithic or Bronze age groups have been named as pioneer cultivators. These theses were tested by examining fossil pollen studies (FPSs), obtained from the European Pollen Database. Many FPSs report Cannabis or Humulus (C/H) with collective names (e.g. Cannabis/Humulus or Cannabaceae). To dissect these aggregate data, we used ecological proxies to differentiate C/H pollen, as follows: unknown C/H pollen that appeared in a pollen assemblage suggestive of steppe (Poaceae, Artemisia, Chenopodiaceae) we interpreted as wild-type Cannabis. C/H pollen in a mesophytic forest assemblage (Alnus, Salix, Populus) we interpreted as Humulus. C/H pollen curves that upsurged and appeared de novo alongside crop pollen grains we interpreted as cultivated hemp. FPSs were mapped and compared to the territories of archaeological cultures. We analysed 479 FPSs from the Holocene/Late Glacial, plus 36 FPSs from older strata. The results showed C/H pollen consistent with wild-type C. sativa in steppe and dry tundra landscapes throughout Europe during the early Holocene, Late Glacial, and previous glaciations. During the warm and wet Holocene Climactic Optimum, forests replaced steppe, and Humulus dominated. Cannabis retreated to steppe refugia. C/H pollen consistent with cultivated hemp first appeared in the Pontic-Caspian steppe refugium. GIS mapping linked cultivation with the Copper age Varna/Gumelni?a culture, and the Bronze age Yamnaya and Terramara cultures. An Iron age steppe culture, the Scythians, likely introduced hemp cultivation to Celtic and Proto-Slavic cultures.  相似文献   

20.
Quantifying the strength of interactions among introduced and native species across space and time is critical in understanding biological invasions as they can attenuate or amplify the magnitude of impact. The European woodwasp, Sirex noctilio F., a global threat to pines, is a recent invader to North America. It attacks and kills primarily Pinus resinosa and Pinus sylvestris, and encounters a diverse assemblage of potential competitors for this resource. We quantified spatial colonization patterns of this woodwasp and resident competitors including scolytine bark beetles, woodboring cerambycid and buprestid beetles, and the fungal root rot diseases Armillaria and Heterobasidion across an 80 year old pine plantation over 4 years. All xylophages were spatially aggregated, but only on a localized scale of 15–20 m. Colonizers occurred non-randomly within trees, with S. noctilio negatively or neutrally associated with all other colonizing agents, whereas all other insect and root rot colonizers were mostly positively co-associated. An autologistic regression with spatially-weighted variables indicated the probability of a dead tree exhibiting symptoms of S. noctilio attack was positively associated with tree density, host species (P. sylvestris), and density of S. noctilio-attacked trees from the current and previous year. Interspecific stand patterns were weaker; probability of attack was negatively associated only with root rot pathogens. Across spatial scales, there were mixed (woodborers) and neutral (bark beetles) associations between S. noctilio and other co-colonizing insects. Our results suggest that competitive interactions with resident species may be contributing to the limited success of S. noctilio in North America, but are unlikely to be driving it by themselves.  相似文献   

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