353 research outputs found
The Holobiont Imperative: perspectives from early emerging animals
This book examines how the growing knowledge of the huge range of animal-bacterial interactions, whether in shared ecosystems or intimate symbioses, is fundamentally altering our understanding of animal biology. Individuals from simple invertebrates to human are not solitary, homogenous entities but consist of complex communities of many species that likely evolved during a billion years of coexistence. Defining the individual microbe-host conversations in these consortia, is a challenging but necessary step on the path to understanding the function of the associations as a whole. The hologenome theory of evolution considers the holobiont with its hologenome as a unit of selection in evolution. This new view may have profound impact on understanding a strictly microbe/symbiont-dependent life style and its evolutionary consequences. It may also affect the way how we approach complex environmental diseases from corals (coral bleaching) to human (inflammatory bowel disease etc). The book is written for scientists as well as medically interested persons in the field of immunobiology, microbiology, evolutionary biology, evolutionary medicine and corals
A novel colorimetric biosensor based on non-aggregated Au@Ag core–shell nanoparticles for methamphetamine and cocaine detection
We report a novel colorimetric biosensor based on non-aggregation Au@Ag core-shell nanoparticles to detect methamphetamine and cocaine. The biosensor consisted of a reporter probe (RP) that is a specific single-stranded DNA (ssDNA) sequence coated on Au@Ag nanoparticles, a capture probe (CP) conjugated with magnetic beads, and an illicit drug-binding DNA aptamer (Apt). Au@Ag nanoparticles were synthesized by seed growth and characterized by scanning electron microscope (SEM), high-resolution transmission electron microscopy (HR-TEM), and UV–vis spectra. Methamphetamine (METH) was used as an example to evaluate the feasibility of the biosensor and to optimize the detection conditions. We demonstrated that this sensing platform was able to detect as low as 0.1 nM (14.9 ng L−1) METH with a negligible interference from other common illicit drugs. Various concentrations of METH were spiked into urines, and the biosensor yielded recoveries more than 83.1%. In addition, the biosensor also showed a high sensitivity to detect cocaine. These results demonstrated that our colorimetric sensor holds promise to be implemented as a visual sensing platform to detect multiple illicit drugs in biological samples and environmental matrices
In vivo evidence for NMDA receptor mediated excitotoxicity in a murine genetic model of Huntington Disease
N-methyl-D-aspartate receptor (NMDAR) mediated excitotoxicity is implicated as a proximate cause of neurodegeneration in Huntington Disease (HD). However, this hypothesis has not been tested rigorously in vivo. NMDAR NR2B-subunits are the predominant NR2 subunit expressed by the striatal medium spiny neurons that degenerate in HD. To test this hypothesis, we crossed a well validated murine genetic model of HD (Hdh(CAG)150) with a transgenic line overexpressing NMDAR NR2B-subunits. In the resulting double mutant line, we show exacerbation of selective striatal neuron degeneration. These results provide the first direct in vivo evidence of NR2B-NMDAR mediated excitotoxicity in the context of HD. Our results are consistent with prior suggestions that direct and/or indirect interactions of mutant huntingtin with NMDARs are a proximate cause of neurodegeneration in HD
Immunocompetence in Hydra. Epithelial cells recognize self-nonself and react against it
The evolution of effective immunologic defense mechanisms in multicellular organisms involves the ability of host cells to distinguish betweeen self and nonself and to react appropriately to eliminate foreign tissue. By producing interspecies grafts we have obtained evidence that immunorecognition followed by incompatibility reactions occur in Hydra. Our results demonstrate that epithelial cells of Hydra recognize and phagocytose foreign hydra cells, indicating that they are the effector cells in the incompatibility reactions. This observation is consistent with the idea that immunocompetence appeared early in the evolution of multicellular organisms
Role of the cellular environment in interstitial stem cell proliferation in Hydra
The role of the cellular environment on hydra stem cell proliferation and differentiation was investigated by introduction of interstitial cells into host tissue of defined cellular composition. In epithelial tissue lacking all non-epithelial cells the interstitial cell population did not grow but differentiated into nerve cells and nematocytes. In host tissue with progressively increased numbers of nerve cells growth of the interstitial cell population was positively correlated to the nerve cell density. In agreement with previous observations (Bode et al. 1976), growth of the interstitial cell population was also found to be negatively correlated to the level of interstitial cells present. The strong correlation between the growth of the interstitial cell population and the presence of interstitial cells and nerve cells implies that interstitial cell proliferation is controlled by a feedback signal from interstitial cells and their derivatives. Our results suggest that the cellular environment of interstitial cells provides cues which are instrumental in stem cell decision making
ERdj5 is the ER reductase that catalyzes the removal of non-native disulfides and correct folding of the LDL receptor
ERdj5 is a member of the protein disulfide isomerase family of proteins localized to the endoplasmic reticulum (ER) of mammalian cells. To date, only a limited number of substrates for ERdj5 are known. Here we identify a number of endogenous substrates that form mixed disulfides with ERdj5, greatly expanding its client repertoire. ERdj5 previously had been thought to exclusively reduce disulfides in proteins destined for dislocation to the cytosol for degradation. However, we demonstrate here that for one of the identified substrates, the low-density lipoprotein receptor (LDLR), ERdj5 is required not for degradation, but rather for efficient folding. Our results demonstrate that the crucial role of ERdj5 is to reduce non-native disulfides formed during productive folding and that this requirement is dependent on its interaction with BiP. Hence, ERdj5 acts as the ER reductase, both preparing misfolded proteins for degradation and catalyzing the folding of proteins that form obligatory non-native disulfides
Stimulation of adenosine receptor enhances α1 -adrenergic receptor-mediated activation of phospholipase C and Ca2+ mobilization in a pertussis toxin-sensitive manner in FRTL-5 thyroid cells
AbstractNorepinephrine (NE) stimulated FRTL-5 thyroid cells via an α1-adrenergic receptor, resulting in cytosolic Ca2+ ([Ca2+]i) mobilization and activation of phospholipase C. Adenosine and its receptor agonist, phenylisopropyladenosine (PIA), although not exerting a direct effect, markedly enhanced the NE-induced changes. Basal NE action was not totally abolished whereas the permissive action of adenosine and PIA was completely abolished by pretreatment of the cells with islet-activating protein (IAP), pertussis toxin. The decrease in cAMP level induced by adenosine or PIA is not the cause of their permissive effect, since this effect was not reversed by the addition of cAMP-increasing agents. We conclude that an IAP substrate GTP-binding protein(s) plays a novel role in forming a stimulatory coupling between an adenosine receptor and an α1-adrenergic receptor-coupled phospholipase C system
The Thousand Aviator Study - Smoking history correlates of selected physiological, biochemical, and anthropometric measures
Smoking history correlates of selected physiological, biochemical, and anthropometric measure
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Papillary Thyroid Carcinoma Variants are Characterized by Co-dysregulation of Immune and Cancer Associated Genes.
Papillary thyroid carcinoma (PTC) variants exhibit different prognosis, but critical characteristics of PTC variants that contribute to differences in pathogenesis are not well-known. This study aims to characterize dysregulated immune-associated and cancer-associated genes in three PTC subtypes to explore how the interplay between cancer and immune processes causes differential prognosis. RNA-sequencing data from The Cancer Genome Atlas (TCGA) were used to identify dysregulated genes in each variant. The dysregulation profiles of the subtypes were compared using functional pathways clustering and correlations to relevant clinical variables, genomic alterations, and microRNA regulation. We discovered that the dysregulation profiles of classical PTC (CPTC) and the tall cell variant (TCPTC) are similar and are distinct from that of the follicular variant (FVPTC). However, unique cancer or immune-associated genes are associated with clinical variables for each subtype. Cancer-related genes MUC1, FN1, and S100-family members were the most clinically relevant in CPTC, while APLN and IL16, both immune-related, were clinically relevant in FVPTC. RAET-family members, also immune-related, were clinically relevant in TCPTC. Collectively, our data suggest that dysregulation of both cancer and immune associated genes defines the gene expression landscapes of PTC variants, but different cancer or immune related genes may drive the phenotype of each variant
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Comprehensive Immune Monitoring of Clinical Trials to Advance Human Immunotherapy.
The success of immunotherapy has led to a myriad of clinical trials accompanied by efforts to gain mechanistic insight and identify predictive signatures for personalization. However, many immune monitoring technologies face investigator bias, missing unanticipated cellular responses in limited clinical material. We present here a mass cytometry (CyTOF) workflow for standardized, systems-level biomarker discovery in immunotherapy trials. To broadly enumerate immune cell identity and activity, we established and extensively assessed a reference panel of 33 antibodies to cover major cell subsets, simultaneously quantifying activation and immune checkpoint molecules in a single assay. This assay enumerates ≥98% of peripheral immune cells with ≥4 positively identifying antigens. Robustness and reproducibility are demonstrated on multiple samples types, across two research centers and by orthogonal measurements. Using automated analysis, we identify stratifying immune signatures in bone marrow transplantation-associated graft-versus-host disease. Together, this validated workflow ensures comprehensive immunophenotypic analysis and data comparability and will accelerate biomarker discovery
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