It is thought that monocytes rapidly differentiate to macrophages or dendritic cells (DCs) upon leaving blood. Here we have shown that Ly-6C+ monocytes constitutively trafficked into skin, lung, and ...lymph nodes (LNs). Entry was unaffected in gnotobiotic mice. Monocytes in resting lung and LN had similar gene expression profiles to blood monocytes but elevated transcripts of a limited number of genes including cyclo-oxygenase-2 (COX-2) and major histocompatibility complex class II (MHCII), induced by monocyte interaction with endothelium. Parabiosis, bromodoxyuridine (BrdU) pulse-chase analysis, and intranasal instillation of tracers indicated that instead of contributing to resident macrophages in the lung, recruited endogenous monocytes acquired antigen for carriage to draining LNs, a function redundant with DCs though differentiation to DCs did not occur. Thus, monocytes can enter steady-state nonlymphoid organs and recirculate to LNs without differentiation to macrophages or DCs, revising a long-held view that monocytes become tissue-resident macrophages by default.
•Ly-6C+ not Ly-6C− monocytes enter tissues in the steady state•Tissue monocytes can retain monocyte profile without becoming macrophages or DCs•Tissue monocytes may mediate antigen surveillance: they are MHCII+ and migrate to LNs•MHCII induction on tissue monocytes can be driven by interactions with endothelium
Acupuncture has become popular and widely practiced in many countries around the world. Despite the large amount of acupuncture-related literature that has been published, broader trends in the ...prevalence and scope of acupuncture research remain underexplored. The current study quantitatively analyzes trends in acupuncture research publications in the past 20 years.
A bibliometric approach was used to search PubMed for all acupuncture-related research articles including clinical and animal studies. Inclusion criteria were articles published between 1995 and 2014 with sufficient information for bibliometric analyses. Rates and patterns of acupuncture publication within the 20 year observational period were estimated, and compared with broader publication rates in biomedicine. Identified eligible publications were further analyzed with respect to study type/design, clinical condition addressed, country of origin, and journal impact factor.
A total of 13,320 acupuncture-related publications were identified using our search strategy and eligibility criteria. Regression analyses indicated an exponential growth in publications over the past two decades, with a mean annual growth rate of 10.7%. This compares to a mean annual growth rate of 4.5% in biomedicine. A striking trend was an observed increase in the proportion of randomized clinical trials (RCTs), from 7.4% in 1995 to 20.3% in 2014, exceeding the 4.5% proportional growth of RCTs in biomedicine. Over the 20 year period, pain was consistently the most common focus of acupuncture research (37.9% of publications). Other top rankings with respect to medical focus were arthritis, neoplasms/cancer, pregnancy or labor, mood disorders, stroke, nausea/vomiting, sleep, and paralysis/palsy. Acupuncture research was conducted in 60 countries, with the top 3 contributors being China (47.4%), United States (17.5%), and United Kingdom (8.2%). Retrieved articles were published mostly in complementary and alternative medicine (CAM) journals with impact factors ranging between 0.7 and 2.8 in the top 20 journals, followed by journals specializing in neuroscience, pain, anesthesia/analgesia, internal medicine and comprehensive fields.
Acupuncture research has grown markedly in the past two decades, with a 2-fold higher growth rate than for biomedical research overall. Both the increases in the proportion of RCTs and the impact factor of journals support that the quality of published research has improved. While pain was a consistently dominant research focus, other topics gained more attention during this time period. These findings provide a context for analyzing strengths and gaps in the current state of acupuncture research, and for informing a comprehensive strategy for further advancing the field.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Cardiac macrophages are crucial for tissue repair after cardiac injury but are not well characterized. Here we identify four populations of cardiac macrophages. At steady state, resident macrophages ...were primarily maintained through local proliferation. However, after macrophage depletion or during cardiac inflammation, Ly6chi monocytes contributed to all four macrophage populations, whereas resident macrophages also expanded numerically through proliferation. Genetic fate mapping revealed that yolk-sac and fetal monocyte progenitors gave rise to the majority of cardiac macrophages, and the heart was among a minority of organs in which substantial numbers of yolk-sac macrophages persisted in adulthood. CCR2 expression and dependence distinguished cardiac macrophages of adult monocyte versus embryonic origin. Transcriptional and functional data revealed that monocyte-derived macrophages coordinate cardiac inflammation, while playing redundant but lesser roles in antigen sampling and efferocytosis. These data highlight the presence of multiple cardiac macrophage subsets, with different functions, origins, and strategies to regulate compartment size.
•Yolk-sac and fetal monocyte progenitors give rise to adult cardiac macrophages•Yolk-sac macrophages persisted into adulthood only in the heart, liver, and brain•Embryonically established resident macrophages can be replaced by blood monocytes•Cardiac macrophages differentially activate T cells and take up dying cardiomyocytes
At present, transgenes in Caenorhabditis elegans are generated by injecting DNA into the germline. The DNA assembles into a semistable extrachromosomal array composed of many copies of injected DNA. ...These transgenes are typically overexpressed in somatic cells and silenced in the germline. We have developed a method that inserts a single copy of a transgene into a defined site. Mobilization of a Mos1 transposon generates a double-strand break in noncoding DNA. The break is repaired by copying DNA from an extrachromosomal template into the chromosomal site. Homozygous single-copy insertions can be obtained in less than 2 weeks by injecting approximately 20 worms. We have successfully inserted transgenes as long as 9 kb and verified that single copies are inserted at the targeted site. Single-copy transgenes are expressed at endogenous levels and can be expressed in the female and male germlines.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
A plasmid Editor (ApE) is a free, multi-platform application for visualizing, designing, and presenting biologically relevant DNA sequences. ApE provides a flexible framework for annotating a ...sequence manually or using a user-defined library of features. ApE can be used in designing plasmids and other constructs
simulation of cloning methods such as PCR, Gibson assembly, restriction-ligation assembly and Golden Gate assembly. In addition, ApE provides a platform for creating visually appealing linear and circular plasmid maps. It is available for Mac, PC, and Linux-based platforms and can be downloaded at https://jorgensen.biology.utah.edu/wayned/ape/.
Bacterial methionine biosynthesis Ferla, Matteo P; Patrick, Wayne M
Microbiology (Society for General Microbiology),
08/2014, Letnik:
160, Številka:
Pt 8
Journal Article
Recenzirano
Odprti dostop
Methionine is essential in all organisms, as it is both a proteinogenic amino acid and a component of the cofactor, S-adenosyl methionine. The metabolic pathway for its biosynthesis has been ...extensively characterized in Escherichia coli; however, it is becoming apparent that most bacterial species do not use the E. coli pathway. Instead, studies on other organisms and genome sequencing data are uncovering significant diversity in the enzymes and metabolic intermediates that are used for methionine biosynthesis. This review summarizes the different biochemical strategies that are employed in the three key steps for methionine biosynthesis from homoserine (i.e. acylation, sulfurylation and methylation). A survey is presented of the presence and absence of the various biosynthetic enzymes in 1593 representative bacterial species, shedding light on the non-canonical nature of the E. coli pathway. This review also highlights ways in which knowledge of methionine biosynthesis can be utilized for biotechnological applications. Finally, gaps in the current understanding of bacterial methionine biosynthesis are noted. For example, the paper discusses the presence of one gene (metC) in a large number of species that appear to lack the gene encoding the enzyme for the preceding step in the pathway (metB), as it is understood in E. coli. Therefore, this review aims to move the focus away from E. coli, to better reflect the true diversity of bacterial pathways for methionine biosynthesis.
Natural killer (NK) cells, like B and T lymphocytes, are potent effector cells that are crucial for immunity to tumors and infections. These effector responses must be controlled to avoid inadvertent ...attack against normal self. Yet, the mechanisms that guide NK cell tolerance differ from those guiding T and B cell tolerance. Here, we discuss how NK cells are licensed by self-MHC class I molecules through their inhibitory receptors which results in NK cell functional competence to be triggered through their activation receptors. We discuss recent data with respect to issues related to licensing, thereby providing a framework for unifying concepts on NK cell education.
The movement paths of individuals over landscapes are basically represented by sequences of points (xi, yi) occurring at times ti. Theoretically, these points can be viewed as being generated by ...stochastic processes that in the simplest cases are Gaussian random walks on featureless landscapes. Generalizations have been made of walks that (i) take place on landscapes with features, (ii) have correlated distributions of velocity and direction of movement in each time interval, (iii) are Lévy processes in which distance or waiting-time (time-between steps) distributions have infinite moments, or (iv) have paths bounded in space and time. We begin by demonstrating that rather mild truncations of fat-tailed step-size distributions have a dramatic effect on dispersion of organisms, where such truncations naturally arise in real walks of organisms bounded by space and, more generally, influenced by the interactions of physiological, behavioral, and ecological factors with landscape features. These generalizations permit not only increased realism and hence greater accuracy in constructing movement pathways, but also provide a biogeographically detailed epistemological framework for interpreting movement patterns in all organisms, whether tossed in the wind or willfully driven. We illustrate the utility of our framework by demonstrating how fission-fusion herding behavior arises among individuals endeavoring to satisfy both nutritional and safety demands in heterogeneous environments. We conclude with a brief discussion of potential methods that can be used to solve the inverse problem of identifying putative causal factors driving movement behavior on known landscapes, leaving details to references in the literature.
We present two derivations of the hyperfine interaction in the ground state of hydrogen using classical electrodynamics. We calculate, at the site of the proton moment
m
→
p, the magnetic field
B
→
e ...due to the magnetization source
M
→
e
(
r
→
) of the relatively extended 1 s electron state. This gives the magnetic interaction via
−
m
→
p
·
B
→
e. One derivation applies the Biot–Savart law to the bound 1 s electric current
J
→
b
=
∇
→
×
M
→ to directly find
B
→
e; the other derivation applies the magnetic version of the Coulomb Law to the bound 1 s magnetic charge density
ρ
b
=
−
∇
→
·
M
→ to first obtain
μ
0
H
→
e and then adds
μ
0
M
→ to find
B
→
e. We show, for any source
M
→, that these two approaches give the same
B
→
(
r
→
), as is expected within classical electrodynamics.
This article describes two classical derivations of the hyperfine interaction in hydrogen. In contrast to familiar derivations, these involve no singularities in the magnetic field of the electron. Instead, the interaction energy of a localized proton magnetic moment in the smooth field of an electron in a 1 s orbital is calculated using both bound magnetic charges and bound currents, and the general equivalence of these two approaches is proved. The analysis is accessible in a junior-level electrodynamics course and connects classical electrodynamics to quantum mechanics, as well as the 21 cm line used in astronomy and astrophysics.
When Enrico Fermi analyzed the magnetic interaction between the electron and Na, Cs, and Rb nuclei in 1930, he used the Dirac equation to compute the energy of an electron interacting with a point ...charge and magnetic dipole (the nucleus) fixed at the origin. After the mathematical dust had settled, he found an interaction that appeared to act only at a single point: the center of the electron wavefunction; it has been called a contact interaction. In 1936, Casimir analyzed the magnetic interaction of proton and neutron spins in the ground state of the deuteron using the Schrödinger equation and classical electrodynamics. Using symmetries appropriate only to s states, and performing an integration by parts, he found that they, too, seemed to interact only at a single common point of the proton and neutron: their center-of-mass. When applied to hydrogen, his result agreed with Fermi's. We present an expanded version of Casimir's important but little-known calculation.
Editor’s Note: In this short note, author Wayne Saslow examines the history of the contact hyperfine interaction, and he revisits and elucidates a calculation by Hendrik Casimir from 1936. The note illustrates how the hyperfine interaction emerges within the framework of classical electrodynamics, and it reveals how the interaction of two spatially extended current distributions can give rise to what appears to be a singular “contact” interaction. The calculation provides a link between classical electrodynamics and quantum mechanics and should be accessible to students in a junior-level electrodynamics course.
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