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1.
Cell ; 183(3): 771-785.e12, 2020 10 29.
Article in English | MEDLINE | ID: mdl-33125892

ABSTRACT

Trained innate immunity, induced via modulation of mature myeloid cells or their bone marrow progenitors, mediates sustained increased responsiveness to secondary challenges. Here, we investigated whether anti-tumor immunity can be enhanced through induction of trained immunity. Pre-treatment of mice with ß-glucan, a fungal-derived prototypical agonist of trained immunity, resulted in diminished tumor growth. The anti-tumor effect of ß-glucan-induced trained immunity was associated with transcriptomic and epigenetic rewiring of granulopoiesis and neutrophil reprogramming toward an anti-tumor phenotype; this process required type I interferon signaling irrespective of adaptive immunity in the host. Adoptive transfer of neutrophils from ß-glucan-trained mice to naive recipients suppressed tumor growth in the latter in a ROS-dependent manner. Moreover, the anti-tumor effect of ß-glucan-induced trained granulopoiesis was transmissible by bone marrow transplantation to recipient naive mice. Our findings identify a novel and therapeutically relevant anti-tumor facet of trained immunity involving appropriate rewiring of granulopoiesis.


Subject(s)
Granulocytes/immunology , Immunity, Innate , Neoplasms/immunology , Adaptive Immunity , Adoptive Transfer , Animals , Epigenesis, Genetic , Interferon Type I/metabolism , Mice, Inbred C57BL , Monocytes/metabolism , Neoplasms/pathology , Neutrophils/metabolism , Phenotype , Receptor, Interferon alpha-beta/deficiency , Receptor, Interferon alpha-beta/metabolism , Transcription, Genetic , Transcriptome/genetics , beta-Glucans/metabolism
2.
Cell ; 172(1-2): 147-161.e12, 2018 01 11.
Article in English | MEDLINE | ID: mdl-29328910

ABSTRACT

Trained innate immunity fosters a sustained favorable response of myeloid cells to a secondary challenge, despite their short lifespan in circulation. We thus hypothesized that trained immunity acts via modulation of hematopoietic stem and progenitor cells (HSPCs). Administration of ß-glucan (prototypical trained-immunity-inducing agonist) to mice induced expansion of progenitors of the myeloid lineage, which was associated with elevated signaling by innate immune mediators, such as IL-1ß and granulocyte-macrophage colony-stimulating factor (GM-CSF), and with adaptations in glucose metabolism and cholesterol biosynthesis. The trained-immunity-related increase in myelopoiesis resulted in a beneficial response to secondary LPS challenge and protection from chemotherapy-induced myelosuppression in mice. Therefore, modulation of myeloid progenitors in the bone marrow is an integral component of trained immunity, which to date, was considered to involve functional changes of mature myeloid cells in the periphery.


Subject(s)
Immunity, Innate , Immunologic Memory , Myeloid Progenitor Cells/immunology , Animals , Cells, Cultured , Granulocyte-Macrophage Colony-Stimulating Factor/metabolism , Interleukin-1beta/metabolism , Male , Mice , Mice, Inbred C57BL , Myeloid Progenitor Cells/drug effects , Myelopoiesis/immunology , beta-Glucans/pharmacology
3.
Kidney Int ; 105(6): 1263-1278, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38286178

ABSTRACT

Current classification of chronic kidney disease (CKD) into stages using indirect systemic measures (estimated glomerular filtration rate (eGFR) and albuminuria) is agnostic to the heterogeneity of underlying molecular processes in the kidney thereby limiting precision medicine approaches. To generate a novel CKD categorization that directly reflects within kidney disease drivers we analyzed publicly available transcriptomic data from kidney biopsy tissue. A Self-Organizing Maps unsupervised artificial neural network machine-learning algorithm was used to stratify a total of 369 patients with CKD and 46 living kidney donors as healthy controls. Unbiased stratification of the discovery cohort resulted in identification of four novel molecular categories of disease termed CKD-Blue, CKD-Gold, CKD-Olive, CKD-Plum that were replicated in independent CKD and diabetic kidney disease datasets and can be further tested on any external data at kidneyclass.org. Each molecular category spanned across CKD stages and histopathological diagnoses and represented transcriptional activation of distinct biological pathways. Disease progression rates were highly significantly different between the molecular categories. CKD-Gold displayed rapid progression, with significant eGFR-adjusted Cox regression hazard ratio of 5.6 [1.01-31.3] for kidney failure and hazard ratio of 4.7 [1.3-16.5] for composite of kidney failure or a 40% or more eGFR decline. Urine proteomics revealed distinct patterns between the molecular categories, and a 25-protein signature was identified to distinguish CKD-Gold from other molecular categories. Thus, patient stratification based on kidney tissue omics offers a gateway to non-invasive biomarker-driven categorization and the potential for future clinical implementation, as a key step towards precision medicine in CKD.


Subject(s)
Disease Progression , Glomerular Filtration Rate , Kidney , Precision Medicine , Renal Insufficiency, Chronic , Transcriptome , Humans , Precision Medicine/methods , Renal Insufficiency, Chronic/pathology , Renal Insufficiency, Chronic/urine , Renal Insufficiency, Chronic/diagnosis , Renal Insufficiency, Chronic/physiopathology , Middle Aged , Female , Male , Kidney/pathology , Kidney/physiopathology , Aged , Biopsy , Adult , Neural Networks, Computer , Case-Control Studies , Gene Expression Profiling , Unsupervised Machine Learning
4.
Nature ; 554(7690): 56-61, 2018 02 01.
Article in English | MEDLINE | ID: mdl-29364871

ABSTRACT

The planarian Schmidtea mediterranea is an important model for stem cell research and regeneration, but adequate genome resources for this species have been lacking. Here we report a highly contiguous genome assembly of S. mediterranea, using long-read sequencing and a de novo assembler (MARVEL) enhanced for low-complexity reads. The S. mediterranea genome is highly polymorphic and repetitive, and harbours a novel class of giant retroelements. Furthermore, the genome assembly lacks a number of highly conserved genes, including critical components of the mitotic spindle assembly checkpoint, but planarians maintain checkpoint function. Our genome assembly provides a key model system resource that will be useful for studying regeneration and the evolutionary plasticity of core cell biological mechanisms.


Subject(s)
Evolution, Molecular , Genome/genetics , Planarians/cytology , Planarians/genetics , Animals , Cell Cycle Proteins/deficiency , Genomics , M Phase Cell Cycle Checkpoints/genetics , M Phase Cell Cycle Checkpoints/physiology , Mad2 Proteins/deficiency , Planarians/physiology , Regeneration/genetics , Reproduction, Asexual/genetics , Retroelements/genetics
5.
Hepatology ; 75(4): 881-897, 2022 04.
Article in English | MEDLINE | ID: mdl-34519101

ABSTRACT

BACKGROUND AND AIMS: NAFLD is initiated by steatosis and can progress through fibrosis and cirrhosis to HCC. The RNA binding protein human antigen R (HuR) controls RNAs at the posttranscriptional level; hepatocyte HuR has been implicated in the regulation of diet-induced hepatic steatosis. The present study aimed to understand the role of hepatocyte HuR in NAFLD development and progression to fibrosis and HCC. APPROACH AND RESULTS: Hepatocyte-specific, HuR-deficient mice and control HuR-sufficient mice were fed either a normal diet or an NAFLD-inducing diet. Hepatic lipid accumulation, inflammation, fibrosis, and HCC development were studied by histology, flow cytometry, quantitative PCR, and RNA sequencing. The liver lipidome was characterized by lipidomics analysis, and the HuR-RNA interactions in the liver were mapped by RNA immunoprecipitation sequencing. Hepatocyte-specific, HuR-deficient mice displayed spontaneous hepatic steatosis and fibrosis predisposition compared to control HuR-sufficient mice. On an NAFLD-inducing diet, hepatocyte-specific HuR deficiency resulted in exacerbated inflammation, fibrosis, and HCC-like tumor development. A multi-omic approach, including lipidomics, transcriptomics, and RNA immunoprecipitation sequencing revealed that HuR orchestrates a protective network of hepatic-metabolic and lipid homeostasis-maintaining pathways. Consistently, HuR-deficient livers accumulated, already at steady state, a triglyceride signature resembling that of NAFLD livers. Moreover, up-regulation of secreted phosphoprotein 1 expression mediated, at least partially, fibrosis development in hepatocyte-specific HuR deficiency on an NAFLD-inducing diet, as shown by experiments using antibody blockade of osteopontin. CONCLUSIONS: HuR is a gatekeeper of liver homeostasis, preventing NAFLD-related fibrosis and HCC, suggesting that the HuR-dependent network could be exploited therapeutically.


Subject(s)
Carcinoma, Hepatocellular , ELAV-Like Protein 1 , Liver Neoplasms , Non-alcoholic Fatty Liver Disease , Animals , Carcinoma, Hepatocellular/pathology , ELAV-Like Protein 1/metabolism , Homeostasis , Inflammation/metabolism , Liver/pathology , Liver Cirrhosis/metabolism , Liver Neoplasms/pathology , Mice , Mice, Inbred C57BL , Non-alcoholic Fatty Liver Disease/pathology , RNA , Triglycerides/metabolism
6.
Proc Natl Acad Sci U S A ; 117(14): 7729-7738, 2020 04 07.
Article in English | MEDLINE | ID: mdl-32213584

ABSTRACT

Every cell produces thousands of distinct lipid species, but insight into how lipid chemical diversity contributes to biological signaling is lacking, particularly because of a scarcity of methods for quantitatively studying lipid function in living cells. Using the example of diacylglycerols, prominent second messengers, we here investigate whether lipid chemical diversity can provide a basis for cellular signal specification. We generated photo-caged lipid probes, which allow acute manipulation of distinct diacylglycerol species in the plasma membrane. Combining uncaging experiments with mathematical modeling, we were able to determine binding constants for diacylglycerol-protein interactions, and kinetic parameters for diacylglycerol transbilayer movement and turnover in quantitative live-cell experiments. Strikingly, we find that affinities and kinetics vary by orders of magnitude due to diacylglycerol side-chain composition. These differences are sufficient to explain differential recruitment of diacylglycerol binding proteins and, thus, differing downstream phosphorylation patterns. Our approach represents a generally applicable method for elucidating the biological function of single lipid species on subcellular scales in quantitative live-cell experiments.


Subject(s)
Diglycerides/chemistry , Lipids/chemistry , Proteins/metabolism , Adenosine Triphosphate/metabolism , Biosensing Techniques , Cell Membrane/metabolism , Cell Membrane/radiation effects , Cell Survival , Isoenzymes/metabolism , Kinetics , Light , Models, Biological , Protein Kinase C/metabolism , Signal Transduction
7.
EMBO J ; 36(17): 2642-2658, 2017 09 01.
Article in English | MEDLINE | ID: mdl-28765163

ABSTRACT

The generation of neocortical neurons from neural progenitor cells (NPCs) is primarily controlled by transcription factors binding to DNA in the context of chromatin. To understand the complex layer of regulation that orchestrates different NPC types from the same DNA sequence, epigenome maps with cell type resolution are required. Here, we present genomewide histone methylation maps for distinct neural cell populations in the developing mouse neocortex. Using different chromatin features, we identify potential novel regulators of cortical NPCs. Moreover, we identify extensive H3K27me3 changes between NPC subtypes coinciding with major developmental and cell biological transitions. Interestingly, we detect dynamic H3K27me3 changes on promoters of several crucial transcription factors, including the basal progenitor regulator Eomes We use catalytically inactive Cas9 fused with the histone methyltransferase Ezh2 to edit H3K27me3 at the Eomes locus in vivo, which results in reduced Tbr2 expression and lower basal progenitor abundance, underscoring the relevance of dynamic H3K27me3 changes during neocortex development. Taken together, we provide a rich resource of neocortical histone methylation data and outline an approach to investigate its contribution to the regulation of selected genes during neocortical development.


Subject(s)
Gene Expression Regulation, Developmental , Histones/genetics , Neocortex/metabolism , Neural Stem Cells/physiology , Animals , Epigenesis, Genetic , Gene Expression Profiling , Genome , Methylation , Mice, Transgenic , Neurogenesis/physiology
8.
Mass Spectrom Rev ; 39(1-2): 212-226, 2020 03.
Article in English | MEDLINE | ID: mdl-30921495

ABSTRACT

In addition to degradation products, impurities, and exogenous contaminants, industries such as pharmaceutical, food, and others must concern themselves with leachables. These chemicals can derive from containers and closures or migrate from labels or secondary containers and packaging to make their way into products. Identification and quantification of extractables (potential leachables) and leachables, typically trace level analytes, is a regulatory expectation intended to ensure consumer safety and product fidelity. Mass spectrometry and related techniques have played a significant role in the analysis of extractables and leachables (E&L). This review provides an overview of how mass spectrometry is used for E&L studies, primarily in the context of the pharmaceutical industry. This review includes work flows, examples of how identification and quantification is done, and the importance of orthogonal data from several different detectors. E&L analyses are driven by the need for consumer safety. These studies are expected to expand in existing areas (e.g., food, textiles, toys, etc.) and into new, currently unregulated product areas. Thus, this topic is of interest to audiences beyond just the pharmaceutical and health care industries. Finally, the potential of universal detector approaches used in other areas is suggested as an opportunity to drive E&L research progress in this arguably understudied, under-published realm.


Subject(s)
Drug Contamination , Drug Packaging , Mass Spectrometry/methods , Drug Packaging/instrumentation , Drug Packaging/methods , Humans , Mass Spectrometry/instrumentation , Materials Testing , Pharmaceutical Preparations/chemistry
9.
Nucleic Acids Res ; 47(D1): D812-D820, 2019 01 08.
Article in English | MEDLINE | ID: mdl-30496475

ABSTRACT

Flatworms (Platyhelminthes) are a basally branching phylum that harbours a wealth of fascinating biology, including planarians with their astonishing regenerative abilities and the parasitic tape worms and blood flukes that exert a massive impact on human health. PlanMine (http://planmine.mpi-cbg.de/) has the mission objective of providing both a mineable sequence repository for planarians and also a resource for the comparative analysis of flatworm biology. While the original PlanMine release was entirely based on transcriptomes, the current release transitions to a more genomic perspective. Building on the recent availability of a high quality genome assembly of the planarian model species Schmidtea mediterranea, we provide a gene prediction set that now assign existing transcripts to defined genomic coordinates. The addition of recent single cell and bulk RNA-seq datasets greatly expands the available gene expression information. Further, we add transcriptomes from a broad range of other flatworms and provide a phylogeny-aware interface that makes evolutionary species comparisons accessible to non-experts. At its core, PlanMine continues to utilize the powerful InterMine framework and consistent data annotations to enable meaningful inter-species comparisons. Overall, PlanMine 3.0 thus provides a host of new features that makes the fascinating biology of flatworms accessible to the wider research community.


Subject(s)
Biodiversity , Databases, Genetic , Platyhelminths/genetics , Transcriptome/genetics , Animals , Gene Expression Profiling , Genome/genetics , Genomics/trends , Humans , Internet , Phylogeny
10.
Proteomics ; 20(23): e1900049, 2020 12.
Article in English | MEDLINE | ID: mdl-32663363

ABSTRACT

Absolute (molar) quantification of proteins determines their molar ratios in complexes, networks, and metabolic pathways. MS Western workflow is employed to determine molar abundances of proteins potentially critical for morphogenesis and phototransduction (PT) in eyes of Drosophila melanogaster using a single chimeric 264 kDa protein standard that covers, in total, 197 peptides from 43 proteins. The majority of proteins are independently quantified with two to four proteotypic peptides with the coefficient of variation of less than 15%, better than 1000-fold dynamic range and sub-femtomole sensitivity. Here, the molar abundance of proteins of the PT machinery and of the rhabdomere, the photosensitive organelle, is determined in eyes of wild-type flies as well as in crumbs (crb) mutant eyes, which exhibit perturbed rhabdomere morphogenesis.


Subject(s)
Drosophila Proteins , Drosophila melanogaster , Animals , Eye/metabolism , Eye Proteins , Membrane Proteins , Morphogenesis , Proteomics
11.
PLoS Genet ; 13(11): e1007107, 2017 Nov.
Article in English | MEDLINE | ID: mdl-29176774

ABSTRACT

Symmetry breaking is involved in many developmental processes that form bodies and organs. One of them is the epithelial rotation of developing tubular and acinar organs. However, how epithelial cells move, how they break symmetry to define their common direction, and what function rotational epithelial motions have remains elusive. Here, we identify a dynamic actomyosin network that breaks symmetry at the basal surface of the Drosophila follicle epithelium of acinar-like primitive organs, called egg chambers, and may represent a candidate force-generation mechanism that underlies the unidirectional motion of this epithelial tissue. We provide evidence that the atypical cadherin Fat2, a key planar cell polarity regulator in Drosophila oogenesis, directs and orchestrates transmission of the intracellular actomyosin asymmetry cue onto a tissue plane in order to break planar actomyosin symmetry, facilitate epithelial rotation in the opposite direction, and direct the elongation of follicle cells. In contrast, loss of this rotational motion results in anisotropic non-muscle Myosin II pulses that are disorganized in plane and causes cell deformations in the epithelial tissue of Drosophila eggs. Our work demonstrates that atypical cadherins play an important role in the control of symmetry breaking of cellular mechanics in order to facilitate tissue motion and model epithelial tissue. We propose that their functions may be evolutionarily conserved in tubular/acinar vertebrate organs.


Subject(s)
Actomyosin/metabolism , Drosophila melanogaster/metabolism , Epithelial Cells/metabolism , Epithelium/metabolism , Animals , Animals, Genetically Modified , Cadherins/genetics , Cadherins/metabolism , Cell Movement , Drosophila Proteins/genetics , Drosophila Proteins/metabolism , Drosophila melanogaster/genetics , Female , Green Fluorescent Proteins/genetics , Green Fluorescent Proteins/metabolism , Microscopy, Confocal , Myosin Light Chains/genetics , Myosin Light Chains/metabolism , Ovary/cytology , Ovary/metabolism , Ovum/metabolism , Rotation , Time-Lapse Imaging/methods
12.
Anal Chem ; 91(18): 12085-12093, 2019 09 17.
Article in English | MEDLINE | ID: mdl-31441640

ABSTRACT

Quantitative bottom-up shotgun lipidomics relies on molecular species-specific "signature" fragments consistently detectable in tandem mass spectra of analytes and standards. Molecular species of glycerophospholipids are typically quantified using carboxylate fragments of their fatty acid moieties produced by higher-energy collisional dissociation of their molecular anions. However, employing standards whose fatty acids moieties are similar, yet not identical, to the target lipids could severely compromise their quantification. We developed a generic and portable fragmentation model implemented in the open-source LipidXte software that harmonizes the abundances of carboxylate anion fragments originating from fatty acid moieties having different sn-1/2 positions at the glycerol backbone, length of the hydrocarbon chain, and number and location of double bonds. The postacquisition adjustment enables unbiased absolute (molar) quantification of glycerophospholipid species independent of instrument settings, collision energy, and employed internal standards.


Subject(s)
Glycerophospholipids/analysis , Lipidomics , Models, Molecular , Software , Tandem Mass Spectrometry
13.
Nucleic Acids Res ; 44(D1): D764-73, 2016 Jan 04.
Article in English | MEDLINE | ID: mdl-26578570

ABSTRACT

Planarian flatworms are in the midst of a renaissance as a model system for regeneration and stem cells. Besides two well-studied model species, hundreds of species exist worldwide that present a fascinating diversity of regenerative abilities, tissue turnover rates, reproductive strategies and other life history traits. PlanMine (http://planmine.mpi-cbg.de/) aims to accomplish two primary missions: First, to provide an easily accessible platform for sharing, comparing and value-added mining of planarian sequence data. Second, to catalyze the comparative analysis of the phenotypic diversity amongst planarian species. Currently, PlanMine houses transcriptomes independently assembled by our lab and community contributors. Detailed assembly/annotation statistics, a custom-developed BLAST viewer and easy export options enable comparisons at the contig and assembly level. Consistent annotation of all transcriptomes by an automated pipeline, the integration of published gene expression information and inter-relational query tools provide opportunities for mining planarian gene sequences and functions. For inter-species comparisons, we include transcriptomes of, so far, six planarian species, along with images, expert-curated information on their biology and pre-calculated cross-species sequence homologies. PlanMine is based on the popular InterMine system in order to make the rich biology of planarians accessible to the general life sciences research community.


Subject(s)
Databases, Genetic , Planarians/genetics , Animals , Data Mining , Gene Expression Profiling , Genes, Helminth , Phenotype , Planarians/metabolism , Sequence Analysis
14.
Proc Natl Acad Sci U S A ; 109(29): 11836-41, 2012 Jul 17.
Article in English | MEDLINE | ID: mdl-22753484

ABSTRACT

The expansion of the neocortex during mammalian brain evolution results primarily from an increase in neural progenitor cell divisions in its two principal germinal zones during development, the ventricular zone (VZ) and the subventricular zone (SVZ). Using mRNA sequencing, we analyzed the transcriptomes of fetal human and embryonic mouse VZ, SVZ, and cortical plate. In mouse, the transcriptome of the SVZ was more similar to that of the cortical plate than that of the VZ, whereas in human the opposite was the case, with the inner and outer SVZ being highly related to each other despite their cytoarchitectonic differences. We describe sets of genes that are up- or down-regulated in each germinal zone. These data suggest that cell adhesion and cell-extracellular matrix interactions promote the proliferation and self-renewal of neural progenitors in the developing human neocortex. Notably, relevant extracellular matrix-associated genes include distinct sets of collagens, laminins, proteoglycans, and integrins, along with specific sets of growth factors and morphogens. Our data establish a basis for identifying novel cell-type markers and open up avenues to unravel the molecular basis of neocortex expansion during evolution.


Subject(s)
Biological Evolution , Extracellular Matrix Proteins/metabolism , Gene Expression Regulation, Developmental/genetics , Neocortex/growth & development , Neocortex/metabolism , Stem Cells/cytology , Transcriptome/genetics , Analysis of Variance , Animals , Cell Adhesion/physiology , Cluster Analysis , DNA Primers/genetics , Fetus/metabolism , Gene Expression Profiling , Humans , Immunohistochemistry , Laser Capture Microdissection , Mice , Polymerase Chain Reaction , Principal Component Analysis , RNA, Messenger/genetics , Sequence Analysis, RNA
15.
Epilepsia Open ; 9(3): 1059-1066, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38593277

ABSTRACT

OBJECTIVE: To assess asymptomatic rates and severity of SARS-CoV-2 infection in people with epilepsy and their healthcare workers in a long-term care facility which had implemented weekly surveillance testing between April 2020 and June 2022. METHODS: Questionnaires focused on objective and subjective COVID-19 symptoms for people with epilepsy residing in and their healthcare workers at the Chalfont Centre for Epilepsy in June 2022. Demographic information, comorbidities, and seizure frequency were gathered from medical records. We also collected responses on objective and subjective COVID-19 symptoms from healthcare workers who participated in a prospective study assessing the reaction to COVID-19 vaccinations (SAFER). RESULTS: Fifty-five out of 89 (62%) residents tested positive at least once on weekly PCR testing for SARS-CoV-2 during the period of interest; 20 of those (37%) were asymptomatic. In comparison, of those 63 healthcare workers who tested positive at least once on weekly testing during the same period, only four (6%) were asymptomatic. Of the 159 healthcare workers who also participated in the SAFER study, 41 tested positive at least once, and seven (17%) were completely asymptomatic during infection with SARS-CoV-2. SIGNIFICANCE: People with epilepsy living in a long-term care facility were more likely to present with asymptomatic SARS-CoV-2 infections than healthcare workers at the same facility. Despite possible bias in the reporting of subjective symptoms due to management-by-proxy, there is no evidence that vulnerable people living in an epilepsy long-term care facility showed reduced resilience towards infections. PLAIN LANGUAGE SUMMARY: People with epilepsy living in care home facilities had a surprisingly high degree of asymptomatic infections with SARS-CoV-2. Very few residents had severe or fatal outcomes. This is in stark contrast to the widely reported bad outcomes for people without epilepsy in other care homes. People with epilepsy reported significantly less symptoms than their healthcare workers. No changes in seizure frequency during or after infection were observed.


Subject(s)
COVID-19 , Epilepsy , Health Personnel , Long-Term Care , Humans , COVID-19/epidemiology , Female , Male , Middle Aged , Adult , Aged , SARS-CoV-2 , Prospective Studies , Surveys and Questionnaires , COVID-19 Vaccines/administration & dosage , Asymptomatic Infections/epidemiology
16.
Arch Insect Biochem Physiol ; 77(4): 179-98, 2011 Aug.
Article in English | MEDLINE | ID: mdl-21638308

ABSTRACT

Ips typographus (L.), the eight-spined spruce bark beetle, causes severe damage throughout Eurasian spruce forests and suitable nuclear markers are needed in order to study its population structure on a genetic level. Two closely related genes encoding α-amylase in I. typographus were characterized and named AmyA and AmyB. Both α-amylase paralogs consisted of six exons and five introns. AmyA encodes a polypeptide of 483 amino acids, whereas AmyB has two alternative transcripts encoding polypeptides of 483 and 370 amino acids. The expression levels of both genes were high during larval stage and adulthood. The AmyB transcripts were absent in the pupal stage. A modification of the allozyme staining method allowed us to detect two clusters of bands on the electrophoretic gel that may correspond to the two α-amylase genes. There was a correlation between the lack of AmyB expression in pupa and the absence of the fast migrating isozyme cluster at this stage, suggesting that the faster migrating isoforms are products of the AmyB gene, whereas the slowly migrating bands are derived from the AmyA.


Subject(s)
Coleoptera/enzymology , Insect Proteins/metabolism , Sequence Homology, Amino Acid , alpha-Amylases/metabolism , Amino Acid Sequence , Animals , Base Sequence , Cloning, Molecular , Coleoptera/genetics , Electrophoresis, Polyacrylamide Gel , Electrophoresis, Starch Gel , Insect Proteins/genetics , Isoenzymes/genetics , Isoenzymes/metabolism , Molecular Sequence Data , Phylogeny , RNA, Messenger/metabolism , alpha-Amylases/genetics
17.
Concepts Magn Reson Part B Magn Reson Eng ; 37B(1): 13-19, 2010 Feb 17.
Article in English | MEDLINE | ID: mdl-20182555

ABSTRACT

We present the construction and performance of a 20-µL active volume probe that utilizes zero-susceptibility wire for the detection transceiver coil and a 3.5 mm outer diameter thin-wall bubble flow cell to contain the sample. The probe shows good rf homogeneity, resolution, line shape and sensitivity. The sensitivity and resolution of the 20-µL probe was compared to those for several other coil configurations, including smaller detection volumes, a thin wire copper coil immersed in susceptibility matching perfluorocarbon FC-43 (fluorinert) fluid, and a standard 5 mm probe. In particular, the (1)H mass sensitivity, S(m) (SNR per micromole), was 3-4 fold higher than that for the standard 5 mm probe. Finally, the use of the zero-susceptibility wire in smaller volume probes is discussed along with potential future improvements and applications.

18.
Adv Radiat Oncol ; 5(5): 834-839, 2020.
Article in English | MEDLINE | ID: mdl-33083645

ABSTRACT

PURPOSE: Recurrent intracranial metastases after whole-brain irradiation pose a clinical challenge owing to the escalating morbidity associated with their treatment. Although stereotactic radiosurgery is increasingly being used, there are still situations in which whole-brain reirradiation (ReRT) continues to be appropriate. Here, we report our experience using whole-brain pulsed reduced dose rate radiation therapy (PRDR), a method that delivers radiation at a slower rate of 0.067 Gy/min to potentially increase sublethal damage repair and decrease toxicity. METHODS AND MATERIALS: Patients undergoing whole-brain ReRT with PRDR from January 1, 2001 to March 2019 were analyzed. The median PRDR ReRT dose was 26 Gy in 2 Gy fractions, resulting in a median total whole-brain dose of 59.5 Gy. Cox regression analysis was used for multivariate analysis. The Kaplan-Meier method was used for overall survival, progression free survival, and to evaluate the ReRT score. Binary logistic regression was employed to evaluate variables associated with rapid death. RESULTS: Seventy-five patients were treated with whole-brain PRDR radiation therapy. The median age was 54 (range, 26-72), the median Karnofsky performance status (KPS) was 80, and 86.7% had recursive partitioning analysis scores of 2. Thirty-two patients had over 10 metastases and 11 had leptomeningeal disease. The median overall survival was 4.1 months (range, 0.29-59.5 months) with a 1 year overall survival of 10.4%. Age, KPS, dexamethasone usage, and intracranial disease volume were significantly correlated with overall survival on multivariate analysis. A KPS ≤70 was associated with rapid death after radiation. The prognostic value of the ReRT score was validated. The most common acute toxicities were fatigue (23.1%) and headache (16.9%). CONCLUSIONS: In this large cohort of patients with advanced intracranial metastases, PRDR achieves acceptable survival and may decrease toxicity associated with ReRT. PRDR is an easily implemented technique and is a viable treatment option for ReRT of brain metastases.

19.
J Vis Exp ; (148)2019 06 03.
Article in English | MEDLINE | ID: mdl-31205315

ABSTRACT

Drosophila immature eggs are called egg chambers, and their structure resembles primitive organs that undergo morphological changes from a round to an ellipsoid shape during development. This developmental process is called oogenesis and is crucial to generating functional mature eggs to secure the next fly generation. For these reasons, egg chambers have served as an ideal and relevant model to understand animal organ development. Several in vitro culturing protocols have been developed, but there are several disadvantages to these protocols. One involves the application of various covers that exert an artificial pressure on the imaged egg chambers in order to immobilize them and to increase the imaged acquisition plane of the circumferential surface of the analyzed egg chambers. Such an approach may negatively influence the behavior of the thin actomyosin machinery that generates the power to rotate egg chambers around their longer axis. Thus, to overcome this limitation, we culture Drosophila egg chambers freely in the media in order to reliably analyze actomyosin machinery along the circumference of egg chambers. In the first part of the protocol, we provide a manual detailing how to analyze the actomyosin machinery in a limited acquisition plane at the local cellular scale (up to 15 cells). In the second part of the protocol, we provide users with a new Fiji-based plugin that allows the simple extraction of a defined thin layer of the egg chambers' circumferential surface. The following protocol then describes how to analyze actomyosin signals at the tissue scale (>50 cells). Finally, we pinpoint the limitations of these approaches at both the local cellular and tissue scales and discuss its potential future development and possible applications.


Subject(s)
Actomyosin/metabolism , Drosophila Proteins/metabolism , Motion Pictures , Ovum/metabolism , Actin Cytoskeleton , Animals , Drosophila , Drosophila melanogaster/metabolism , Female , Oogenesis , Ovum/cytology , Time-Lapse Imaging , Tissue Culture Techniques
20.
Nat Metab ; 1(1): 111-124, 2019 01.
Article in English | MEDLINE | ID: mdl-30886999

ABSTRACT

Transferrin receptor 2 (Tfr2) is mainly expressed in the liver and controls iron homeostasis. Here, we identify Tfr2 as a regulator of bone homeostasis that inhibits bone formation. Mice lacking Tfr2 display increased bone mass and mineralization independent of iron homeostasis and hepatic Tfr2. Bone marrow transplantation experiments and studies of cell-specific Tfr2 knockout mice demonstrate that Tfr2 impairs BMP-p38MAPK signaling and decreases expression of the Wnt inhibitor sclerostin specifically in osteoblasts. Reactivation of MAPK or overexpression of sclerostin rescues skeletal abnormalities in Tfr2 knockout mice. We further show that the extracellular domain of Tfr2 binds BMPs and inhibits BMP-2-induced heterotopic ossification by acting as a decoy receptor. These data indicate that Tfr2 limits bone formation by modulating BMP signaling, possibly through direct interaction with BMP either as a receptor or as a co-receptor in a complex with other BMP receptors. Finally, the Tfr2 extracellular domain may be effective in the treatment of conditions associated with pathological bone formation.

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