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151.
Mycoplasma suis belongs to the haemotrophic mycoplasmas which colonise red blood cells of a wide range of vertebrates. Adhesion to red blood cells is the crucial step in the unique lifecycle of M. suis. Due to the lack of a cultivation system, identification of adhesion structures has been difficult. So far, only one adhesion protein, i.e. MSG1 was identified. In order to determine further adhesion molecules of M. suis, we screened genomic M. suis libraries and performed Southern blot hybridisation analyses of genomic M. suis DNA. The α-enolase of M. suis was identified and analysed genetically and functionally. The encoding gene has 1623 bp in size. The deduced amino acid sequence showed an overall identity of 59.6-65.1% to α-enolases of other pathogenic mycoplasmas. The 540 aa M. suis α-enolase displays a size extension of about 90 aa in comparison to α-enolases of other mycoplasmas. Recombinant α-enolase expressed in Escherichia coli demonstrated immunogenicity in experimentally infected pigs. Immunoblot, confocal laser scanning microscopy and immune electron microscopy analysis using antibodies against recombinant α-enolase, indicate the membrane and surface localisation of native α-enolase in M. suis, though no typical signal sequences exist. Furthermore, we showed that recombinant α-enolase binds to porcine erythrocyte lysate in a dose-dependent manner. E. coli transformants which express α-enolase on their surface acquire the ability to adhere to porcine red blood cells. In conclusion, our observations indicate that α-enolase could be involved in the adhesion of M. suis to porcine red blood cells.  相似文献   
152.
Stenosing tenosynovitis of the abductor pollicis longus muscle causes chronic front limb lameness in dogs. The lesion, similar to de Quervain's tenosynovitis in people, is caused by repetitive movements of the carpus. Thirty dogs with front limb lameness, painful carpal flexion, and a firm soft tissue swelling medial to the carpus were examined prospectively. Seven dogs had bilateral abductor pollicis longus tenosynovitis. Radiographs of the carpus were characterized by a deeper radiolucent medial radial sulcus and bony proliferations medial and slightly cranial to the distal radius, resulting in stenosis of the tendon sheath and subsequent tendinitis. Ultrasonographic examination of the firm soft tissue swelling medial to the carpus was characterized by an irregular hypoechoic abductor pollicis longus tendon or tendinitis in 22 of 37 dogs. Nineteen of 37 abductor pollicis longus tendon sheaths were fluid-filled and all tendon sheaths were thickened, more hyperechoic, with small hyperechoic mineralizations embedded in the connective tissue of the abductor pollicis longus tendon sheath in 25 dogs. Enthesopathy of the abductor pollicis longus tendon was identified in seven dogs. While radiographs of stenosing tenosynovitis of the abductor pollicis longus are helpful in visualizing the deep radial sulcus and osteophytes medial to the distal radius, ultrasonography is useful to distinguish between lesions of the tendon or tendon sheath and to determine thickness and fluid content of the abductor pollicis longus tendon sheath.  相似文献   
153.
Pancreatic trauma and rupture are rare after feline high-rise syndrome; however, should it happen, pancreatic enzymes will leak into the abdominal cavity and may cause pancreatic autodigestion and fatty tissue saponification. If not diagnosed and treated, it can ultimately lead to multiorgan failure and death. In this case series, 700 records of high-rise syndrome cats that presented between April 2001 and May 2006 were analysed, and four cats with pancreatic rupture were identified. Clinical signs, diagnosis using ultrasonography and lipase activity in blood and abdominal effusion, and treatment modalities are reported. Three cats underwent surgical abdominal exploration, one cat was euthanased. Rupture of the left pancreatic limb was confirmed in all cases. Two of the operated cats survived to date. High-rise syndrome can lead to abdominal trauma, including pancreatic rupture. A prompt diagnosis and surgical treatment should be considered.  相似文献   
154.
Over a period of 34 years (1954–1987), a total of 11.9 million glass eels were stocked all over Austria to improve the yields of commercial fishermen and to make the lakes more attractive for anglers. Nearly half (48%) of the imported glass eels were introduced into natural, previously eel‐free Alpine lakes until stocking ceased in 1988. Twenty‐five years later, their occurrence could be verified in 56% (N = 22) of the Austrian Alpine lakes larger than 50 ha and mean body length had increased to 66 cm. Eels from seven selected Austrian Alpine lakes exhibited a yearly mean increase in length between 0.6 and 1.5 cm, indicating a comparatively poor growth compared with the majority of eel populations from within their natural distribution range. At the same time, high expectations in developing a flourishing eel fishery were not met. In all but one lake, the harvest remained below 3% of the total yearly catch and salmonids remained the dominant target species. During peak harvest in the 1980s, it exceeded 8% in mesotrophic Wallersee (2600 kg). Simulations of stock development indicated that the yield could have been improved, but contrary to earlier expectations eels never became important for local cuisine and catches remained too low for the development of a profitable export business. On the other hand, eels may have contributed to the loss of small‐bodied fish taxa.  相似文献   
155.
Neonatal mastitis is a rare occurrence in the horse. This report documents a case of mastitis caused by an organism within the Streptococcus dysgalactiae group in a 1-week-old Paint filly.  相似文献   
156.
Equine granulocytic anaplasmosis (EGA) and Lyme borreliosis (LB) are an emerging concern in Canada. We estimated the seroprevalence of EGA and equine LB by testing 376 convenience serum samples from 3 provinces using a point-of-care SNAP® 4Dx® ELISA (IDEXX Laboratories, Westbrook, Maine, USA), and investigated the agreement between the point-of-care ELISA and laboratory-based serologic tests. The estimated seroprevalence for EGA was 0.53% overall (0.49% in Saskatchewan, 0.71% in Manitoba), while the estimated seroprevalence for LB was 1.6% overall (0.49% in Saskatchewan, 2.86% in Manitoba). There was limited agreement between the point-of-care ELISA and an indirect fluorescent antibody test for EGA (kappa 0.1, PABAK 0.47) and an ELISA/Western blot combination for LB (kappa 0.23, PABAK 0.71). While the SNAP® 4Dx® ELISA yielded expected seroprevalence estimates, further evaluation of serologic tests for the purposes of disease exposure recognition may be needed.  相似文献   
157.
Wastewater treatment plants (WWTP) with insufficient technologies for wastewater purification often cause a distinct nutrient pollution in the receiving streams. The increased concentrations of dissolved nutrients can severely disturb the ecological integrity of streams, which has been recently shown for basic ecosystem processes like mineralization of coarse particulate organic matter (CPOM). The present study investigated the impact of a modern WWTP (Zentralkläranlage Jena) on breakdown rates of CPOM exposed in net bags (1 mm mesh size) to the effluent of a large municipal WWTP and an upstream control site in the Saale River (Thuringia, Germany) from April to October 2005. Control and effluent site differed significantly in water chemistry with increased concentrations of dissolved organic carbon (DOC), ammonium, sulfate, and chloride at the effluent site, while the control site displayed higher concentrations of nitrate. However, breakdown rates of toothpickers and small twigs were not significantly different between the sites, whereas breakdown rate of leaf litter was significantly higher at the effluent site (k?=?0.0124 day?1) than at the control site (k?=?0.0095 day?1). Benthic invertebrate assemblages inhabiting the sandy stream bed at both sites were dominated by Chironomidae and Oligochaeta, typical inhabitants of fine sediments. Although the Shannon diversity of the benthic invertebrates was slightly higher at the effluent site (0.85) than at the control site (0.63), no significant difference could be detected. Bacterial numbers in water samples and surface biofilms on glass slides also displayed no significant differences between the two sites. This study showed that the effluents of a WWTP with modern technologies for wastewater purification did not directly affect breakdown rates of CPOM, bacteria numbers in epibenthic biofilms and the water column, and the community composition of sediment inhabiting aquatic macroinvertebrates in an effluent-receiving river with already increased concentrations of dissolved nutrients.  相似文献   
158.
Human gammadelta T cells are considered to play a vital role in protective immunity through cytokine secretion and cytotoxic activity. We report that cells expressing the Vgamma2Vdelta2+-T cell receptor (Vdelta2+ T cells) also display principal characteristics of professional antigen-presenting cells such as dendritic cells. Thus, when activated, these cells efficiently processed and displayed antigens and provided co-stimulatory signals sufficient for strong induction of na?ve alphabeta T cell proliferation and differentiation. We suggest that, upon microbial activation, Vdelta2+ T cells participate in the induction of adaptive immune responses and that these cells may be a useful tool in vaccine development and immunotherapy.  相似文献   
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