1,601 research outputs found
Detection of triplex PCR for the modified qualitative soybean and maize genetically
A molecular screening method based on multiplex PCR that involves amplification of specific soybean or maize sequences from plant DNA (lectin or zein) and the amplification of 35S promoter and NOS terminator,for the detection of genetically modified soybean and maize was developed. The new method is proposed,for the simulicmeous cletcctimt of tree genetic elements in the.same run as reliable method for rapid detection of genetically, modified plants with sensitivity of 0.1%
Regulation of Dendritic Cell Migration to the Draining Lymph Node: Impact on T Lymphocyte Traffic and Priming
Antigen-pulsed dendritic cells (DCs) are used as natural adjuvants for vaccination, but the factors that influence the efficacy of this treatment are poorly understood. We investigated the parameters that affect the migration of subcutaneously injected mouse-mature DCs to the draining lymph node. We found that the efficiency of DC migration varied with the number of injected DCs and that CCR7+/+ DCs migrating to the draining lymph node, but not CCR7ā/ā DCs that failed to do so, efficiently induced a rapid increase in lymph node cellularity, which was observed before the onset of T cell proliferation. We also report that DC migration could be increased up to 10-fold by preinjection of inflammatory cytokines that increased the expression of the CCR7 ligand CCL21 in lymphatic endothelial cells. The magnitude and quality of CD4+ T cell response was proportional to the number of antigen-carrying DCs that reached the lymph node and could be boosted up to 40-fold by preinjection of tumor necrosis factor that conditioned the tissue for increased DC migration. These results indicate that DC number and tissue inflammation are critical parameters for DC-based vaccination
As fontes de stress no trabalho
O stress tem consequĆŖncias para a saĆŗde e para a qualidade de vida. Estas sĆ£o percebidas por licenƧas mĆ©dicas, queda de produtividade, dificuldades interpessoais, gerando altos custos pessoais e profissionais. Faz-se necessĆ”ria a identificaĆ§Ć£o de fontes estressoras nas organizaƧƵes que interferem no bem estar e desempenho individual. O objetivo do estudo Ć© levantar estas fontes e sua intensidade, para ser possĆvel desenvolver medidas de profilaxia e de intervenĆ§Ć£o, tornando o ambiente de trabalho mais satisfatĆ³rio. Participaram deste estudo 144 adultos, entre gerentes, empresĆ”rios, psicĆ³logos, administradores, engenheiros, etc. Utilizou-se um questionĆ”rio de 12 fontes de stressĀ no trabalho. As mais relatadas foram: excesso de atividades, falta de planejamento e conflitos de interesses e valores. Os profissionais com maior nĆŗmero delas foram os engenheiros, autĆ“nomos e administradores, nĆ£o havendo diferenƧa significativa entre os gĆŖneros. Concluiu-se que os participantes tiveram um nĆŗmero alto de fontes e de intensidade destas. Sugere-se um maior aprofundamento deste estudo com mais sujeito
Differential requirements for the chemokine receptor CCR7 in T cell activation during Listeria monocytogenes infection
Effective priming of T cell responses depends on cognate interactions between naive T cells and professional antigen-presenting cells (APCs). This contact is the result of highly coordinated migration processes, in which the chemokine receptor CCR7 and its ligands, CCL19 and CCL21, play a central role. We used the murine Listeria monocytogenes infection model to characterize the role of the CCR7/CCR7 ligand system in the generation of T cell responses during bacterial infection. We demonstrate that efficient priming of naive major histocompatibility complex (MHC) class Iaārestricted CD8+ T cells requires CCR7. In contrast, MHC class Ibārestricted CD8+ T cells and MHC class IIārestricted CD4+ T cells seem to be less dependent on CCR7; memory T cell responses are independent of CCR7. Infection experiments with bone marrow chimeras or mice reconstituted with purified T cell populations indicate that CCR7 has to be expressed on CD8+ T cells and professional APCs to promote efficient MHC class Iaārestricted T cell priming. Thus, different T cell subtypes and maturation stages have discrete requirements for CCR7
Angiotensin-II-Evoked Ca2+ Entry in Murine Cardiac Fibroblasts Does Not Depend on TRPC Channels
TRPC proteins form cation conducting channels regulated by different stimuli and are
regulators of the cellular calcium homeostasis. TRPC are expressed in cardiac cells including cardiac
fibroblasts (CFs) and have been implicated in the development of pathological cardiac remodeling
including fibrosis. Using Ca2+ imaging and several compound TRPC knockout mouse lines we
analyzed the involvement of TRPC proteins for the angiotensin II (AngII)-induced changes in Ca2+
homeostasis in CFs isolated from adult mice. Using qPCR we detected transcripts of all Trpc genes in
CFs; Trpc1, Trpc3 and Trpc4 being the most abundant ones. We show that the AngII-induced Ca2+
entry but also Ca2+ release from intracellular stores are critically dependent on the density of CFs in
culture and are inversely correlated with the expression of the myofibroblast marker Ī±-smooth muscle
actin. Our Ca2+ measurements depict that the AngII- and thrombin-induced Ca2+ transients, and the
AngII-induced Ca2+ entry and Ca2+ release are not affected in CFs isolated from mice lacking all seven
TRPC proteins (TRPC-hepta KO) compared to control cells. However, pre-incubation with GSK7975A
(10 ĀµM), which sufficiently inhibits CRAC channels in other cells, abolished AngII-induced Ca2+ entry.
Consequently, we conclude the dispensability of the TRPC channels for the acute neurohumoral
Ca2+ signaling evoked by AngII in isolated CFs and suggest the contribution of members of the Orai
channel family as molecular constituents responsible for this pathophysiologically important Ca2+
entry pathway
Topography and instability of monolayers near domain boundaries
We theoretically study the topography of a biphasic surfactant monolayer in
the vicinity of domain boundaries. The differing elastic properties of the two
phases generally lead to a nonflat topography of ``mesas'', where domains of
one phase are elevated with respect to the other phase. The mesas are steep but
low, having heights of up to 10 nm. As the monolayer is laterally compressed,
the mesas develop overhangs and eventually become unstable at a surface tension
of about K(dc)^2 (dc being the difference in spontaneous curvature and K a
bending modulus). In addition, the boundary is found to undergo a
topography-induced rippling instability upon compression, if its line tension
is smaller than about K(dc). The effect of diffuse boundaries on these features
and the topographic behavior near a critical point are also examined. We
discuss the relevance of our findings to several experimental observations
related to surfactant monolayers: (i) small topographic features recently found
near domain boundaries; (ii) folding behavior observed in mixed phospholipid
monolayers and model lung surfactants; (iii) roughening of domain boundaries
seen under lateral compression; (iv) the absence of biphasic structures in
tensionless surfactant films.Comment: 17 pages, 9 figures, using RevTeX and epsf, submitted to Phys Rev
Climate variability and change in the United States: potential impacts on water- and foodborne diseases caused by microbiologic agents.
Exposure to waterborne and foodborne pathogens can occur via drinking water (associated with fecal contamination), seafood (due to natural microbial hazards, toxins, or wastewater disposal) or fresh produce (irrigated or processed with contaminated water). Weather influences the transport and dissemination of these microbial agents via rainfall and runoff and the survival and/or growth through such factors as temperature. Federal and state laws and regulatory programs protect much of the U.S. population from waterborne disease; however, if climate variability increases, current and future deficiencies in areas such as watershed protection, infrastructure, and storm drainage systems will probably increase the risk of contamination events. Knowledge about transport processes and the fate of microbial pollutants associated with rainfall and snowmelt is key to predicting risks from a change in weather variability. Although recent studies identified links between climate variability and occurrence of microbial agents in water, the relationships need further quantification in the context of other stresses. In the marine environment as well, there are few studies that adequately address the potential health effects of climate variability in combination with other stresses such as overfishing, introduced species, and rise in sea level. Advances in monitoring are necessary to enhance early-warning and prevention capabilities. Application of existing technologies, such as molecular fingerprinting to track contaminant sources or satellite remote sensing to detect coastal algal blooms, could be expanded. This assessment recommends incorporating a range of future scenarios of improvement plans for current deficiencies in the public health infrastructure to achieve more realistic risk assessments
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