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1.
Streptococcus equi subsp. zooepidemicus is the pathogen most commonly isolated from the uterus of mares. S. zooepidemicus is an opportunistic pathogen and part of the resident flora in the caudal reproductive tract. The aim of this study was to investigate whether a genotypically distinct subpopulation of S. zooepidemicus is associated with endometritis in the mare, by genotyping and comparing uterine S. zooepidemicus strains with isolates from the vagina and clitoral fossa. Mares with (n = 18) or without (n = 11) clinical symptoms of endometritis were included. Uterine samples were obtained using a guarded endometrial biopsy punch, whereas a swab was used to recover samples from the cranial vagina and the clitoral fossa. If S. zooepidemicus was present, up to three colonies were selected from each anatomical location (max. 9 isolates per mare). Bacterial isolates were characterized by pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST). S. zooepidemicus was isolated from the endometrium of 12 mares. A total of 88 isolates were analyzed by PFGE: 31 from the endometrium, 26 from the cranial vagina and 31 isolates from the clitoral fossa. For MLST 21 isolates were chosen. Results demonstrated a higher genetic similarity of the isolates obtained from infectious endometritis compared to isolates obtained from the caudal reproductive tract. In conclusion, we demonstrate for the first time that a genetically distinct group of S. zooepidemicus is associated with infectious endometritis in the mare.  相似文献   
2.
Thirty adult, client-owned dogs were diagnosed with hypothyroidism based on history, physical examination findings, hematologic and biochemical abnormalities, thyrotropin (TSH) response testing, endogenous canine thyrotropin (cTSH) concentration, or both, and total serum thryoxine concentration. All dogs received levothyroxine (L-thyroxine) at an initial dose of 22 μg/kg PO sid in either a tablet (13 dogs) or chewable form (17 dogs). Energy expenditure of each dog during apparent rest was estimated with an open-flow indirect calorimetry system by determining the rates of carbon dioxide production and oxygen consumption. Energy expenditure of apparent rest (EE) was lower in untreated hypothyroid dogs compared with reference values for EE. After treatment with L-thyroxine, EE of the hypothyroid dogs was significantly ( P < .05) higher than pretreatment values.  相似文献   
3.
In a large comparative survey of Danish and Swedish slaughter pig herds performed prior to this work, it was unexpectedly found that some Swedish herds harbored seropositive pigs. Serum samples from the Swedish herds had moderate responses in the Salmonella mix-ELISA (detecting serogroup B and C1 infections) compared to the Danish herds classifying some of them as seropositive using a cut-off value at 40 OD%. In Sweden, extensive Salmonella control is carried out by bacteriological screening of feces and lymph nodes, and the overall prevalence has been proven to be below 0.1%. The serological positive results were therefore unexpected; hence the reactivities of the Swedish sera were studied by a number of immunochemical analyses (Western blot, indirect ELISA, inhibition ELISA, avidity ELISA) and compared to sera from Danish pig herds with verified Salmonella infections ("the reference sera").In Western blot, the Swedish sera had high binding reactivities against Salmonella Typhimurium LPS of different molecular weights, and gave binding patterns similar to that of the reference sera. Pre-incubation with free S. Typhimurium LPS or PS (the polysaccharide part of LPS) was able to inhibit the reactivity of the Swedish sera in the mix-ELISA. Reactivities against other related bacterial LPS such as Citrobacter freundii LPS and Yersinia enterocolitica O:3 LPS were observed in the Swedish sera, but these LPS antigens were unable to inhibit the reactivities in the mix-ELISA as efficiently as S. Typhimurium LPS. Furthermore, the Swedish sera did not bind Salmonella LPS of another serogroup (S. Meleagridis LPS, serogroup E1) or rough Salmonella LPS, both lacking the specific O-antigenic parts of S. Typhimurium LPS. The avidity of the Swedish sera was much lower than the avidity of the reference sera, which could indicate the presence of transient low-dose infections or stimulation by inactivated bacteria in feed. The results obtained in this investigation strongly indicate that the Swedish sera contain antibodies directed against the O-antigenic part of LPS from S. Typhimurium or possibly on as yet unknown bacterium.  相似文献   
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Allicin, an active ingredient of garlic, possesses a range of antimicrobial properties. Unfortunately, certain properties of the compound, such as chemical instability and low miscibility with water, have hampered its practical use in the past. Here, we show that it is possible to use a binary system consisting of the plant enzyme alliinase and its substrate alliin to generate allicin, and hence antifungal activity, in situ. During application, the two inactive components generate compounds that inhibit growth and infection-related development of the rice blast fungus Magnaporthe grisea. It is therefore possible to "trigger" biological activity in a controlled, yet effective manner. Apart from circumventing many of the drawbacks of allicin, this binary system has additional important advantages, such as low toxicity of its individual components and selective activation. Importantly, alliinase is also able to use different substrates, therefore paving the way to a range of novel, binary antimicrobial systems with custom-made chemical and biochemical properties.  相似文献   
7.
In contrast to the woodrotting fungi which can only attack Populus tremula after felling, Phellinus tremulae successfully invades the central part of the living tree. Possible causes for this difference were investigated. It was found that sterile wood samples were decomposed more rapidly by saprophytic fungi than by parasitic fungi. With both types of fungi, heartwood was more resistant to decay than sapwood. It is postulated that living sapwood inhibits infection by most woodrotting fungi, but that P. tremulae can successfully overcome this barrier. This postulate cannot be confirmed by experiments using sterilized wood samples.  相似文献   
8.
From the polar extracts of Origanum vulgare L. ssp. hirtum 19 compounds have been isolated. The structures and relative stereochemistry have been elucidated by spectroscopic analysis and determined as apigenin, luteolin, chrysoeriol, diosmetin, quercetin, eriodictyol, cosmoside, vicenin-2, caffeic acid, p-menth-3-ene-1,2-diol 1-O-beta-glucopyranoside, thymoquinol 2-O-beta-glucopyranoside, thymoquinol 5-O-beta-glucopyranoside, thymoquinol 2,5-O-beta-diglucopyranoside, 12-hydroxyjasmonic acid, 12-hydroxyjasmonic acid 12-O-beta-glucopyranoside, lithospermic acid B, rosmarinic acid, 10-epi-lithospermic acid, and epi-lithospermic acid B. The three latter products display unusual stereochemistry of the 3,4-hydroxyphenyllactic acid unit(s), which to the authors' best knowledge has never been reported before in similar compounds. Moreover, lithospermic acid B (and its stereoisomers), p-menth-3-ene-1,2-diol 1-O-beta-glucopyranoside, 12-hydroxyjasmonic acid, and 12-hydroxyjasmonic acid 12-O-beta-glucopyranoside were isolated for the first time from Origanum species.  相似文献   
9.
Glyoxal, methylglyoxal, and diacetyl formed as Maillard reaction products in heat-treated food were determined in coffee extracts (coffee brews) obtained from green beans and beans with different degrees of roast. The compounds have been reported to be mutagenic in vitro and genotoxic in experimental animals in a number of papers. More recently, alpha-dicarbonyl compounds have been implicated in the glycation process. Our data show that small amounts of glyoxal and methylglyoxal occur naturally in green coffee beans. Their concentrations increase in the early phases of the roasting process and then decline. Conversely, diacetyl is not found in green beans and forms later in the roasting process. Therefore, light and medium roasted coffees had the highest glyoxal and methylglyoxal content, whereas dark roasted coffee contained smaller amounts of glyoxal, methylglyoxal, and diacetyl. For the determination of coffee alpha-dicarbonyl compounds, a reversed-phase high performance liquid chromatography with a diode array detector (RP-HPLC-DAD) method was devised that involved the elimination of interfering compounds, such as chlorogenic acids, by solid phase extraction (SPE) and their derivatization with 1,2-diaminobenzene to give quinoxaline derivatives. Checks of SPE and derivatization conditions to verify recovery and yield, respectively, resulted in rates of 100%. The results of the validation procedure showed that the proposed method is selective, precise, accurate, and sensitive.  相似文献   
10.
Unidentified olive plants naturally grow in the Golestan province of Iran, on different soils and under climates spanning from sub-temperate to desert conditions, represented by single trees or groups of few trees. We collected samples from representative sites and analyzed them by simple sequence repeat markers in order to determine their identity and their relationships to prominent Iranian and Mediterranean reference cultivars. Population structure analysis separated these ecotypes from Mediterranean and, surprisingly, from all Iranian cultivars, the parentage test excluded their direct contribution as candidate parents or offspring of cultivars, and they also showed a high level of admixture. Their differentiation from cultivated olives may be attributed to different factors: they could represent wild plants or could derive from natural dissemination of ancestral cultivated trees. Their survival up to now may be due to the fact that most of them are grown on sacred sites such as necropolis. Anyhow, the adaptation to strong environmental stresses, and their fruit size and oil content make the olive Golestan ecotypes a valuable source of genetic variation previously uncharacterized and currently threatened with extinction.  相似文献   
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