36 research outputs found
Analysis of spatial relationships in three dimensions: tools for the study of nerve cell patterning
<p>Abstract</p> <p>Background</p> <p>Multiple technologies have been brought to bear on understanding the three-dimensional morphology of individual neurons and glia within the brain, but little progress has been made on understanding the rules controlling cellular patterning. We describe new matlab-based software tools, now available to the scientific community, permitting the calculation of spatial statistics associated with 3D point patterns. The analyses are largely derived from the Delaunay tessellation of the field, including the nearest neighbor and Voronoi domain analyses, and from the spatial autocorrelogram.</p> <p>Results</p> <p>Our tools enable the analysis of the spatial relationship between neurons within the central nervous system in 3D, and permit the modeling of these fields based on lattice-like simulations, and on simulations of minimal-distance spacing rules. Here we demonstrate the utility of our analysis methods to discriminate between two different simulated neuronal populations.</p> <p>Conclusion</p> <p>Together, these tools can be used to reveal the presence of nerve cell patterning and to model its foundation, in turn informing on the potential developmental mechanisms that govern its establishment. Furthermore, in conjunction with analyses of dendritic morphology, they can be used to determine the degree of dendritic coverage within a volume of tissue exhibited by mature nerve cells.</p
Requirement of Interaction between Mast Cells and Skin Dendritic Cells to Establish Contact Hypersensitivity
The role of mast cells (MCs) in contact hypersensitivity (CHS) remains controversial. This is due in part to the use of the MC-deficient Kit W/Wv mouse model, since Kit W/Wv mice congenitally lack other types of cells as a result of a point mutation in c-kit. A recent study indicated that the intronic enhancer (IE) for Il4 gene transcription is essential for MCs but not in other cell types. The aim of this study is to re-evaluate the roles of MCs in CHS using mice in which MCs can be conditionally and specifically depleted. Transgenic Mas-TRECK mice in which MCs are depleted conditionally were newly generated using cell-type specific gene regulation by IE. Using this mouse, CHS and FITC-induced cutaneous DC migration were analyzed. Chemotaxis assay and cytoplasmic Ca2+ imaging were performed by co-culture of bone marrow-derived MCs (BMMCs) and bone marrow-derived dendritic cells (BMDCs). In Mas-TRECK mice, CHS was attenuated when MCs were depleted during the sensitization phase. In addition, both maturation and migration of skin DCs were abrogated by MC depletion. Consistently, BMMCs enhanced maturation and chemotaxis of BMDC in ICAM-1 and TNF-α dependent manners Furthermore, stimulated BMDCs increased intracellular Ca2+ of MC upon direct interaction and up-regulated membrane-bound TNF-α on BMMCs. These results suggest that MCs enhance DC functions by interacting with DCs in the skin to establish the sensitization phase of CHS
Development of new microalgae-based sourdough "crostini": functional aspects of Arthrospira platensis (spirulina) addition
The aim of this work was to evaluate the influence of Arthrospira platensis F&M-C256 (spirulina)
incorporation on the nutritional and functional properties of “crostini”, a leavened bakery product
largely consumed in Italy and Europe. Sourdough was used as leavening and fermentation agent and
three concentrations of A. platensis F&M-C256 were tested: 2%, 6% and 10% (w/w). Despite a lower
volume increase compared to the control, the A. platensis F&M-C256 “crostini” doughs reached a
technological appropriate volume after fermentation. At the end of fermentation, no significant
differences in microorganisms concentrations were observed. A. platensis F&M-C256 “crostini” showed
higher protein content compared to the control. Considering the European Commission Regulation on
nutritional claims, “crostini” incorporated with 6% and 10% biomass can be claimed to be a “source
of protein”. Six and ten percent A. platensis “crostini” also presented significantly higher antioxidant
capacity and phenolics. A significantly lower value of in vitro dry matter and protein digestibility
between A. platensis F&M-C256 “crostini” and the control was found. The overall acceptability
decreased with increasing A. platensis F&M-C256 addition. The combination of spirulina biomass
addition and the sourdough technology led to the development of a novel microalgae-based bakery
product with nutritional and functional featuresinfo:eu-repo/semantics/publishedVersio
Precision measurement of violation in the penguin-mediated decay
A flavor-tagged time-dependent angular analysis of the decay
is performed using collision data collected
by the LHCb experiment at % at TeV, the center-of-mass energy of
13 TeV, corresponding to an integrated luminosity of 6 fb^{-1}. The
-violating phase and direct -violation parameter are measured
to be rad and
, respectively, assuming the same values
for all polarization states of the system. In these results, the
first uncertainties are statistical and the second systematic. These parameters
are also determined separately for each polarization state, showing no evidence
for polarization dependence. The results are combined with previous LHCb
measurements using collisions at center-of-mass energies of 7 and 8 TeV,
yielding rad and . This is the most precise study of time-dependent violation
in a penguin-dominated meson decay. The results are consistent with
symmetry and with the Standard Model predictions.Comment: All figures and tables, along with any supplementary material and
additional information, are available at
https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2023-001.html (LHCb
public pages
Iron Behaving Badly: Inappropriate Iron Chelation as a Major Contributor to the Aetiology of Vascular and Other Progressive Inflammatory and Degenerative Diseases
The production of peroxide and superoxide is an inevitable consequence of
aerobic metabolism, and while these particular "reactive oxygen species" (ROSs)
can exhibit a number of biological effects, they are not of themselves
excessively reactive and thus they are not especially damaging at physiological
concentrations. However, their reactions with poorly liganded iron species can
lead to the catalytic production of the very reactive and dangerous hydroxyl
radical, which is exceptionally damaging, and a major cause of chronic
inflammation. We review the considerable and wide-ranging evidence for the
involvement of this combination of (su)peroxide and poorly liganded iron in a
large number of physiological and indeed pathological processes and
inflammatory disorders, especially those involving the progressive degradation
of cellular and organismal performance. These diseases share a great many
similarities and thus might be considered to have a common cause (i.e.
iron-catalysed free radical and especially hydroxyl radical generation). The
studies reviewed include those focused on a series of cardiovascular, metabolic
and neurological diseases, where iron can be found at the sites of plaques and
lesions, as well as studies showing the significance of iron to aging and
longevity. The effective chelation of iron by natural or synthetic ligands is
thus of major physiological (and potentially therapeutic) importance. As
systems properties, we need to recognise that physiological observables have
multiple molecular causes, and studying them in isolation leads to inconsistent
patterns of apparent causality when it is the simultaneous combination of
multiple factors that is responsible. This explains, for instance, the
decidedly mixed effects of antioxidants that have been observed, etc...Comment: 159 pages, including 9 Figs and 2184 reference
Precision measurement of CP violation in the penguin-mediated decay Bs0→ϕϕ
A flavor-tagged time-dependent angular analysis of the decay
B
0
s
→
ϕ
ϕ
is performed using
p
p
collision data collected by the LHCb experiment at the center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of
6
fb
−
1
. The
C
P
-violating phase and direct
C
P
-violation parameter are measured to be
ϕ
s
¯
s
s
s
=
−
0.042
±
0.075
±
0.009
rad
and
|
λ
|
=
1.004
±
0.030
±
0.009
, respectively, assuming the same values for all polarization states of the
ϕ
ϕ
system. In these results, the first uncertainties are statistical and the second systematic. These parameters are also determined separately for each polarization state, showing no evidence for polarization dependence. The results are combined with previous LHCb measurements using
p
p
collisions at center-of-mass energies of 7 and 8 TeV, yielding
ϕ
s
¯
s
s
s
=
−
0.074
±
0.069
rad
and
|
λ
|
=
1.009
±
0.030
. This is the most precise study of time-dependent
C
P
violation in a penguin-dominated
B
meson decay. The results are consistent with
C
P
symmetry and with the standard model predictions