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1.
Int J Biol Macromol ; 272(Pt 2): 132907, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38862318

ABSTRACT

The aim of this study was to develop a star fruit extract (SFE) and incorporate it into aerogels based on native and phosphorylated potato starches. The phosphorylation of starch enhances its properties by incorporating phosphate groups that increase the spaces between starch molecules, resulting in a more resilient, intact aerogel with enhanced water absorption. The bioactive aerogels based on potato starch and 10, 15, and 20 % (w/w) of SFE were characterized by their morphological and thermogravimetric properties, infrared spectra, water absorption capacity, loading capacity, and antioxidant activity. Epicatechin was the major compound present in SFE. The thermal stability of SFE increased when incorporated into phosphorylated starch aerogels at a concentration of 20 %. The water absorption capacity was higher in phosphorylated starch aerogels (reaching 1577 %) than in their native counterparts (reaching 1100 %). Native starch aerogels with 15 and 20 % SFE exhibited higher antioxidant activity against hydroxyl free radicals compared to phosphorylated starch aerogels, achieving 79.9 % and 86.4 % inhibition for the hydroxyl and nitric oxide radicals, respectively. The ideal choice of freeze-dried aerogel depends on the desired effect, either to act as an antioxidant agent by releasing bioactive compounds from SFE or as a water-absorbent agent in food products.


Subject(s)
Antioxidants , Fruit , Gels , Plant Extracts , Solanum tuberosum , Starch , Solanum tuberosum/chemistry , Gels/chemistry , Plant Extracts/chemistry , Plant Extracts/pharmacology , Starch/chemistry , Phosphorylation , Antioxidants/chemistry , Antioxidants/pharmacology , Fruit/chemistry , Averrhoa/chemistry , Water/chemistry
2.
Cell Rep Methods ; 4(5): 100759, 2024 May 20.
Article in English | MEDLINE | ID: mdl-38626768

ABSTRACT

We designed a Nextflow DSL2-based pipeline, Spatial Transcriptomics Quantification (STQ), for simultaneous processing of 10x Genomics Visium spatial transcriptomics data and a matched hematoxylin and eosin (H&E)-stained whole-slide image (WSI), optimized for patient-derived xenograft (PDX) cancer specimens. Our pipeline enables the classification of sequenced transcripts for deconvolving the mouse and human species and mapping the transcripts to reference transcriptomes. We align the H&E WSI with the spatial layout of the Visium slide and generate imaging and quantitative morphology features for each Visium spot. The pipeline design enables multiple analysis workflows, including single or dual reference genome input and stand-alone image analysis. We show the utility of our pipeline on a dataset from Visium profiling of four melanoma PDX samples. The clustering of Visium spots and clustering of H&E imaging features reveal similar patterns arising from the two data modalities.


Subject(s)
Heterografts , Humans , Animals , Mice , Gene Expression Profiling/methods , Eosine Yellowish-(YS) , Hematoxylin , Transcriptome , Image Processing, Computer-Assisted/methods , Xenograft Model Antitumor Assays
3.
bioRxiv ; 2024 Feb 05.
Article in English | MEDLINE | ID: mdl-38370717

ABSTRACT

Resistance of BRAF-mutant melanomas to targeted therapy arises from the ability of cells to enter a persister state, evade treatment with relative dormancy, and repopulate the tumor when reactivated. Using spatial transcriptomics in patient derived xenograft models, we capture clonal lineage evolution during treatment, finding the persister state to show increased oxidative phosphorylation, decreased proliferation, and increased invasive capacity, with central-to-peripheral gradients. Phylogenetic tracing identifies intrinsic- and acquired-resistance mechanisms (e.g. dual specific phosphatases, Reticulon-4, CDK2) and suggests specific temporal windows of potential therapeutic efficacy. Using deep learning to analyze histopathological slides, we find morphological features of specific cell states, demonstrating that juxtaposition of transcriptomics and histology data enables identification of phenotypically-distinct populations using imaging data alone. In summary, we define state change and lineage selection during melanoma treatment with spatiotemporal resolution, elucidating how choice and timing of therapeutic agents will impact the ability to eradicate resistant clones. Statement of Significance: Tumor evolution is accelerated by application of anti-cancer therapy, resulting in clonal expansions leading to dormancy and subsequently resistance, but the dynamics of this process are incompletely understood. Tracking clonal progression during treatment, we identify conserved, global transcriptional changes and local clone-clone and spatial patterns underlying the emergence of resistance.

4.
bioRxiv ; 2023 Jul 30.
Article in English | MEDLINE | ID: mdl-37546876

ABSTRACT

Highlights: We have developed an automated data processing pipeline to quantify mouse and human data from patient-derived xenograft samples assayed by Visium spatial transcriptomics with matched hematoxylin and eosin (H&E) stained image. We enable deconvolution of reads with Xenome, quantification of spatial gene expression from host and graft species with Space Ranger, extraction of B-allele frequencies, and splicing quantification with Velocyto. In the H&E image processing sub-workflow, we generate morphometric and deep learning-derived feature quantifications complementary to the Visium spots, enabling multi-modal H&E/expression comparisons. We have wrapped the pipeline into Nextflow DSL2 in a scalable, portable, and easy-to-use framework. Summary: We designed a Nextflow DSL2-based pipeline, Spatial Transcriptomics Quantification (STQ), for simultaneous processing of 10x Genomics Visium spatial transcriptomics data and a matched hematoxylin and eosin (H&E)-stained whole slide image (WSI), optimized for Patient-Derived Xenograft (PDX) cancer specimens. Our pipeline enables the classification of sequenced transcripts for deconvolving the mouse and human species and mapping the transcripts to reference transcriptomes. We align the H&E WSI with the spatial layout of the Visium slide and generate imaging and quantitative morphology features for each Visium spot. The pipeline design enables multiple analysis workflows, including single or dual reference genomes input and stand-alone image analysis. We showed the utility of our pipeline on a dataset from Visium profiling of four melanoma PDX samples. The clustering of Visium spots and clustering of imaging features of H&E data reveal similar patterns arising from the two data modalities.

5.
Nature ; 620(7974): 651-659, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37468627

ABSTRACT

Even among genetically identical cancer cells, resistance to therapy frequently emerges from a small subset of those cells1-7. Molecular differences in rare individual cells in the initial population enable certain cells to become resistant to therapy7-9; however, comparatively little is known about the variability in the resistance outcomes. Here we develop and apply FateMap, a framework that combines DNA barcoding with single-cell RNA sequencing, to reveal the fates of hundreds of thousands of clones exposed to anti-cancer therapies. We show that resistant clones emerging from single-cell-derived cancer cells adopt molecularly, morphologically and functionally distinct resistant types. These resistant types are largely predetermined by molecular differences between cells before drug addition and not by extrinsic factors. Changes in the dose and type of drug can switch the resistant type of an initial cell, resulting in the generation and elimination of certain resistant types. Samples from patients show evidence for the existence of these resistant types in a clinical context. We observed diversity in resistant types across several single-cell-derived cancer cell lines and cell types treated with a variety of drugs. The diversity of resistant types as a result of the variability in intrinsic cell states may be a generic feature of responses to external cues.


Subject(s)
Antineoplastic Agents , Clone Cells , Drug Resistance, Neoplasm , Neoplasms , Humans , Clone Cells/drug effects , Clone Cells/metabolism , Clone Cells/pathology , DNA Barcoding, Taxonomic , Drug Resistance, Neoplasm/drug effects , Drug Resistance, Neoplasm/genetics , Neoplasms/drug therapy , Neoplasms/genetics , Neoplasms/pathology , RNA-Seq , Single-Cell Gene Expression Analysis , Tumor Cells, Cultured , Antineoplastic Agents/pharmacology
6.
Psychol Rep ; 95(1): 323-30, 2004 Aug.
Article in English | MEDLINE | ID: mdl-15460388

ABSTRACT

The study is focused on the training, demographics, perceived emotional and physical health, past traumatic experience histories, and attachment styles of mental health professionals in the field of trauma (members of the International Society for Traumatic Stress Studies). While the data set is limited by a low response rate of 20%, the uniqueness of the sample and distinctive themes yield insight into the experience of trauma and its association with attachment style.


Subject(s)
Health Personnel/psychology , Life Change Events , Mental Health Associations , Object Attachment , Occupational Diseases/psychology , Stress Disorders, Traumatic/psychology , Adult , Attitude to Health , Crisis Intervention , Cross-Cultural Comparison , Defense Mechanisms , Female , Humans , Male , Middle Aged , Models, Psychological , Occupational Diseases/diagnosis , Occupational Diseases/therapy , Personality Inventory/statistics & numerical data , Professional-Patient Relations , Psychometrics , Self-Assessment , Specialization , Stress Disorders, Traumatic/diagnosis , Stress Disorders, Traumatic/therapy , Surveys and Questionnaires
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