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291.
Jully Gogoi-Tiwari Vincent Williams Charlene Babra Waryah Karina Yui Eto Modiri Tau Paul Costantino 《Biofouling》2013,29(7):543-554
This study was undertaken to compare the immunogenicity and protective potential of biofilm vs planktonic Staphylococcus aureus vaccine for the prevention of mastitis using the mouse as a model system. Mice immunized with formalin-killed whole cell vaccine of S. aureus residing in a biofilm when delivered via an intramammary route produced a cell mediated immune response. Mice immunized with this biofilm vaccine showed significant reductions in colonization by S. aureus in mammary glands, severity of clinical symptoms and tissue damage in mammary glands in comparison with the mice immunized with formalin-killed whole cells of planktonic S. aureus. The planktonic vaccine administered by a subcutaneous route produced a significantly higher humoral immune response (IgG1 and IgG) than the biofilm vaccine. However, considering the host response, tissue damage, the clinical severity and colonization of S. aureus in mammary glands, the biofilm vaccine performed better in immunogenicity and protective potential when administered by the intramammary route. 相似文献
292.
The extinct, exclusively Cretaceous wasp family Maimetshidae is newly recorded from Earliest Cenomanian Burmese amber. Two new genera and species are described. Burmaimetsha concava gen. et sp. nov., based on a male and a female, is most similar to Guyotemaimetsha Perrichot, Nel & Néraudeau, from Albian-Cenomanian French amber, but differs in its larger mandibles, distinctly concave face, elongate antennomeres, and forewing with cell [1Rs] smaller and fourth abscissa of Rs shorter. Maimetshasia kachinensis gen. et sp. nov., is based on a male, and is characterized by asymmetric mandibles with two and three teeth, by its forewing venation without cross-vein 2rs-m, with cell [1M] large and trapezoidal, and vein 2Rs + M very short, and by the hind wing without a free apex of Rs. The family was evidently widespread in the Cretaceous, and the new records extend the paleobiogeographical range to the South-East of Eurasia. A discussion about the possible biology of Maimetshidae is provided. 相似文献
293.
294.
Gregory Genta‐Jouve Lionel Weinberg Vincent Cocandeau Yannick Maestro Olivier Paul Thomas Serge Holderith 《Chirality》2013,25(3):180-184
Coatline A ( 1 ) and α‐epi‐coatline A ( 4 ) co‐occur in the trunk extract of Andira coriacea. Inspection of their chiroptical properties led to intriguing results. After a careful examination of the experimental data used for the previously reported absolute configuration of these compounds, some uncertainties were identified. A combined theoretical approach including conformational analyses and calculation of electronic circular dichroism (ECD) spectra, in addition with experimental data obtained for schoepfin A ( 5 ) and the new schoepfin D ( 6 ) isolated from Senna quinquangulata, allowed the revision of the absolute configuration of coatlines A ( 1 ) and B ( 2 ). Chirality 25:180–184, 2013. © 2012 Wiley Periodicals, Inc. 相似文献
295.
Sébastien Besseau Franziska Kellner Arnaud Lanoue Antje M.K. Thamm Vonny Salim Bernd Schneider Fernando Geu-Flores René H?fer Grégory Guirimand Anthony Guihur Audrey Oudin Ga?lle Glevarec Emilien Foureau Nicolas Papon Marc Clastre Nathalie Giglioli-Guivarc’h Benoit St-Pierre Danièle Werck-Reichhart Vincent Burlat Vincenzo De Luca Sarah E. O’Connor Vincent Courdavault 《Plant physiology》2013,163(4):1792-1803
296.
Kaposi''s sarcoma-associated herpesvirus (KSHV) latency-associated nuclear antigen (LANA) is a 1,162-amino-acid protein that mediates the maintenance of episomal viral genomes in latently infected cells. The two central components of episome persistence are DNA replication with each cell division and the segregation of DNA to progeny nuclei. LANA self-associates to bind KSHV terminal-repeat (TR) DNA and to mediate its replication. LANA also simultaneously binds to TR DNA and mitotic chromosomes to mediate the segregation of episomes to daughter nuclei. The N-terminal region of LANA binds histones H2A and H2B to attach to mitotic chromosomes, while the C-terminal region binds TR DNA and also associates with chromosomes. Both the N- and C-terminal regions of LANA are essential for episome persistence. We recently showed that deletion of all internal LANA sequences results in highly deficient episome maintenance. Here we assess independent internal LANA regions for effects on episome persistence. We generated a panel of LANA mutants that included deletions in the large internal repeat region and in the unique internal sequence. All mutants contained the essential N- and C-terminal regions, and as expected, all maintained the ability to associate with mitotic chromosomes in a wild-type fashion and to bind TR DNA, as assessed by electrophoretic mobility shift assays (EMSA). Deletion of the internal regions did not reduce the half-life of LANA. Notably, deletions within either the repeat elements or the unique sequence resulted in deficiencies in DNA replication. However, only the unique internal sequence exerted effects on the ability of LANA to retain green fluorescent protein (GFP) expression from TR-containing episomes deficient in DNA replication, consistent with a role in episome segregation; this region did not independently associate with mitotic chromosomes. All mutants were deficient in episome persistence, and the deficiencies ranged from minor to severe. Mutants deficient in DNA replication that contained deletions within the unique internal sequence had the most-severe deficits. These data suggest that internal LANA regions exert critical roles in LANA-mediated DNA replication, segregation, and episome persistence, likely through interactions with key host cell factors. 相似文献
297.
Cyril Montoya Adrian Balasescu Sébastien Joannin Vincent Ollivier Jérémie Liagre Samvel Nahapetyan Ruben Ghukasyan David Colonge Boris Gasparyan Christine Chataigner 《Journal of human evolution》2013
The open-air site of Kalavan 1 is located in the Aregunyats mountain chain (at 1640 m above sea level) on the northern bank of Lake Sevan. It is the first Upper Palaeolithic site excavated in Armenia. Led by an Armenian-French team, several excavations (2005–2009) have revealed a well preserved palaeosoil, dated to around 14,000 BP (years before present), containing fauna, lithic artefacts, as well as several hearths and activity areas that structure the settlement. The initial studies enable placement of the site in its environment and justify palaeoethnological analysis of the Epigravettian human groups of the Lesser Caucasus. 相似文献
298.
Louise Vincent 《Ethnic and racial studies》2013,36(8):1426-1451
This paper argues that, while the demise of apartheid has led to many situations in which South Africans now come into closer contact with one another, this increased ‘contact’ does not amount to greater racial integration. Contact occurs within a context of unequal power relations in which ‘whiteness’ continues to be privileged over ‘blackness’. The result is that white people tend to benefit more from contact with the racial ‘other’ than black people, who often experience this contact as reinforcing their expectations of continued white dominance and privilege. While contact may undermine blatantly racist practices and overt racial conflict, racialized patterns of reasoning continue to exist, often unnoticed and unchallenged. These include the assumption that race is an incontrovertible fact of experience, the privileging of whiteness, the assumption that there exist different (biological) races which evince different forms of social behaviour and that these are essential properties of people rather than being historically or socially contingent. 相似文献
299.
Halina Staniek Nicholas R. Rhodes Kristin R. Di Bona Ge Deng Sharifa T. Love Leigh Ann Pledger Jeremy Blount Emmalea Gomberg Frances Grappe Chelsea Cernosek Brittany Peoples Jane F. Rasco Zbigniew Krejpcio John B. Vincent 《Biological trace element research》2013,151(3):373-383
Diabetes results in several metabolic changes, including alterations in the transport, distribution, excretion, and accumulation of metals. While changes have been examined in several rat models of insulin resistance and diabetes, the metal ion concentrations in the tissues of Zucker lean, Zucker obese (an insulin resistance and early stage diabetes model), and Zucker diabetic fatty (ZDF, a type 2 diabetes model) have not previously been examined in detail. The concentration of Cu, Zn, Fe, Mg, and Ca were examined in the liver, kidney, heart and spleen, and Cr concentration in the liver and kidney of these rats were examined. Zucker obese rats have a reduction in the concentration of Cu, Zn, Fe, Mg in the liver compared to ZDF and/or lean Zucker rats, presumably as a result of the increased fat content of the liver of the obese rats. ZDF rats have increased concentrations of kidney Cu compared to the lean rats, while kidney Ca concentrations are increased in the Zucker obese rats. Spleen Fe concentrations are decreased in Zucker obese rats compared to the lean rats. No effects on metal concentrations in the heart were observed between the lean, obese, and ZDF rats, and no effects on Cr concentrations were identified. Cr(III) complexes have previously been shown to have beneficial effects on the signs of insulin resistance in Zucker obese and ZDF rats. The effects of daily gavage administration of chromium picolinate ([Cr(pic)3]) (1 mg?Cr/kg body mass), CrCl3 (1 mg?Cr/kg body mass), and Cr3 ([Cr3O(propionate)6(H2O)3]+) (33 μg and 1 mg?Cr/kg body mass) on metal concentrations in these tissues were examined. Treatment with CrCl3 and Cr3, but not [Cr(pic)3], at 1 mg?Cr/kg resulted in a statistically significant accumulation of Cr in the kidney of lean and obese but not ZDF rats but resulted in lowering the elevated levels of kidney Cu in ZDF rats, suggesting a beneficial effect on this symptom of type 2 diabetes. 相似文献
300.
Tasha Daley Samson N. Omoregie Vincent Wright Felix O. Omoruyi 《Biological trace element research》2013,151(3):400-405
Cadmium is an environmental pollutant of increasing worldwide concern. It has been reported to be high in the soil where food crops are grown in some parishes of Jamaica. Surprisingly, no adverse effect of cadmium has been reported among the Jamaican population. However, phytic acid has also been shown to be high in some food crops grown in Jamaica. In this study, we evaluated the effects of phytic acid (1 %) and exercise on the metabolism of cadmium (5 mg cadmium/kg body weight) in rats. Five groups of rats were fed as follows: rats fed control diet, control diet supplemented with cadmium and subjected to exercise, control diet supplemented with phytic acid plus cadmium and subjected to exercise, control diet supplemented with cadmium plus phytic acid, and control diet supplemented with cadmium only. The animals were fed for 4 weeks and then sacrificed. Blood samples were collected for some biochemical assays. Percentage weight loss (28.42 %) was greatest in the group that had cadmium supplement only. The group fed control diet supplemented with cadmium only displayed increased liver enzymes and electrolytes except for the significant decrease in bicarbonate compared to other test groups. Similarly, blood urea nitrogen and uric acid were increased in the group fed cadmium supplement only compared to other test groups. Total cholesterol trended downwards in the test groups compared to control. These observations suggest that consumption of diet high in phytic acid with relatively high physical activity may be protective against the adverse effects of cadmium. 相似文献