Massive Amplification Research Articles

On the laminar solutions and stability of accelerating and decelerating channel flows

We study the effect of acceleration and deceleration on the stability of channel flows. To do so, we derive an exact solution for laminar profiles of channel flows with an arbitrary, time-varying wall motion and pressure gradient. This solution then allows us to investigate the stability of any unsteady channel flow. In particular, we restrict our investigation to the non-normal growth of perturbations about time-varying base flows with exponentially decaying acceleration and deceleration, with comparisons to growth about a constant base flow (i.e. the time-invariant simple shear or parabolic profile). We apply this acceleration and deceleration through the velocity of the walls and through the flow rate. For accelerating base flows, perturbations never grow larger than perturbations about a constant base flow, while decelerating flows show massive amplification of perturbations – at a Reynolds number of $500$ , properly timed perturbations about the decelerating base flow grow $ {O}(10^5)$ times larger than perturbations grow about a constant base flow. This amplification increases as we raise the rate of deceleration and the Reynolds number. We find that this amplification arises due to a transition from spanwise perturbations leading to the largest amplification to streamwise perturbations leading to the largest amplification that only occurs in the decelerating base flow. By evolving the optimal perturbations through the linearized equations of motion, we reveal that the decelerating base flow achieves this massive amplification through the Orr mechanism, or the down-gradient Reynolds stress mechanism, which accelerating and constant base flows cannot maintain.

Development of a Novel System Consisting of a Reductase-Like Nanozyme and the Reaction of Resazurin and Ammonia Borane for Sensitive Fluorometric Sensing.

We report a novel system consisting of a redox reaction and a highly efficient reductase-like nanozyme, silica-palladium nanoparticles (Pd@SiO2 NPs), as a novel detection platform for fluorometric sensing. In a proof-of-concept demonstration using an oligonucleotide as the detection target, a glass fiber-based sensor is fabricated by covalently conjugating two oligo probes, which are complementary to the adjacent segments of the target oligonucleotide, on Pd@SiO2 NPs and glass fiber, respectively. In the presence of the target oligonucleotide, the two probes are drawn together by the target through sequence-specific hybridization, bringing the Pd@SiO2 NPs to the glass fiber. When the glass fiber is subsequently immersed in a mixture of resazurin and ammonia borane solution, the Pd@SiO2 NPs on the glass fiber trigger the catalytic conversion of resazurin (blue, slightly fluorescent) to resorufin (pink, highly fluorescent) with massive signal amplification, indirectly signaling the presence of the target oligonucleotide. We show that the glass fiber-based fluorometric sensor can detect a target oligonucleotide associated with the BRAF mutation linearly in the concentration range of 20 to 400 pM with a detection limit (LOD) of 15 pM and the specificity to differentiate targets with single-base difference. These results demonstrate a new frontier for the development of a sensitive, specific, and inexpensive nonenzyme-based fluorometric sensing platform as an alternative to conventional enzyme-based assays.

Happiness and Unhappiness Stoic Tourist in Bali

Stoicism is a philosophy that teaches the creation of a happy life. From a tourism perspective, stoicism is the primary goal of tourists visiting a tourist destination. However, some tourists visiting a destination have the opposite experience, feeling uncomfortable, anxious, angry, or even stressed while traveling. Therefore, it is essential to delve deeper into the connection between Stoic behavior and foreign tourists (foreign tourists) through research. Notably, research is needed on the stoic behavior of foreign tourists who enjoy services and products while traveling in Bali. Based on this, this research aims to analyze tourist happiness associated with the travel experience. Data collection methods include interviews, observations, and documentary studies. Respondents are European foreign tourists visiting Bali. The method used is qualitative descriptive analysis. Data analysis uses NVivo to answer the factors influencing Stoic tourists in Bali. This research found eight factors of happiness with the highest percentage. These factors include friendly people, beautiful nature, many tourist activities, delicious food, beautiful culture, a positive vibe, many experiences, and everything in Bali. In the future, stoic tourists will require more massive amplification so that tourism in Bali can be of higher quality and sustainable.

Deciphering cell states and genealogies of human haematopoiesis

The human blood system is maintained through the differentiation and massive amplification of a limited number of long-lived haematopoietic stem cells (HSCs)1. Perturbations to this process underlie diverse diseases, but the clonal contributions to human haematopoiesis and how this changes with age remain incompletely understood. Although recent insights have emerged from barcoding studies in model systems2–5, simultaneous detection of cell states and phylogenies from natural barcodes in humans remains challenging. Here we introduce an improved, single-cell lineage-tracing system based on deep detection of naturally occurring mitochondrial DNA mutations with simultaneous readout of transcriptional states and chromatin accessibility. We use this system to define the clonal architecture of HSCs and map the physiological state and output of clones. We uncover functional heterogeneity in HSC clones, which is stable over months and manifests as both differences in total HSC output and biases towards the production of different mature cell types. We also find that the diversity of HSC clones decreases markedly with age, leading to an oligoclonal structure with multiple distinct clonal expansions. Our study thus provides a clonally resolved and cell-state-aware atlas of human haematopoiesis at single-cell resolution, showing an unappreciated functional diversity of human HSC clones and, more broadly, paving the way for refined studies of clonal dynamics across a range of tissues in human health and disease.

In silico analysis of the Seven IN Absentia (SINA) genes in bread wheat sheds light on their structure in plants.

Seven IN Absentia (SINA) is a small family of genes coding for ubiquitin-ligases that play major roles in regulating various plant growth and developmental processes, as well as in plant response to diverse biotic and abiotic stresses. Here, we studied the SINA genes family in bread wheat Triticum aestivum which is a culture of major importance for food security worldwide. One hundred and forty-one SINA family genes have been identified in bread wheat and showed that their number is very high compared to other plant species such as A. thaliana or rice. The expansion of this family seems to have been more important in monocots than in eudicots. In bread wheat, the chromosome 3 distal region is the site of a massive amplification of the SINA family, since we found that 83 of the 141 SINA genes are located on this chromosome in the Chinese Spring variety. This amplification probably occurred as a result of local duplications, followed by sequences divergence. The study was then extended to 4856 SINA proteins from 97 plant species. Phylogenetic and structural analyses identified a group of putative ancestral SINA proteins in plants containing a 58 aminoacid specific signature. Based on sequence homology and the research of that "Ancestral SINA motif" of 58 amino acids, a methodological process has been proposed and lead to the identification of functional SINA genes in a large family such as the Triticae that might be used for other species. Finally, tis paper gives a comprehensive overview of wheat gene family organization and functionalization taken the SINA genes as an example.

Transposable Element Interactions Shape the Ecology of the Deer Mouse Genome.

The genomic landscape of transposable elements (TEs) varies dramatically across species, with some TEs demonstrating greater success in colonizing particular lineages than others. In mammals, long interspersed nuclear element (LINE) retrotransposons are typically more common than any other TE. Here, we report an unusual genomic landscape of TEs in the deer mouse, Peromyscus maniculatus. In contrast to other previously examined mammals, long terminal repeat elements occupy more of the deer mouse genome than LINEs (11% and 10%, respectively). This pattern reflects a combination of relatively low LINE activity and a massive invasion of lineage-specific endogenous retroviruses (ERVs). Deer mouse ERVs exhibit diverse origins spanning the retroviral phylogeny suggesting they have been host to a wide range of exogenous retroviruses. Notably, we trace the origin of one ERV lineage, which arose ∼5-18 million years ago, to a close relative of feline leukemia virus, revealing inter-ordinal horizontal transmission. Several lineage-specific ERV subfamilies have very high copy numbers, with the top five most abundant accounting for ∼2% of the genome. We also observe a massive amplification of Kruppel-associated box domain-containing zinc finger genes, which likely control ERV activity and whose expansion may have been facilitated by ectopic recombination between ERVs. Finally, we find evidence that ERVs directly impacted the evolutionary trajectory of LINEs by outcompeting them for genomic sites and frequently disrupting autonomous LINE copies. Together, our results illuminate the genomic ecology that shaped the unique deer mouse TE landscape, shedding light on the evolutionary processes that give rise to variation in mammalian genome structure.

Research progress in rolling circle amplification in biosensing and cell imaging

<p indent="0mm">Rolling circle amplification (RCA) is an isothermal nucleic acid amplification technology that performs massive amplification of rolling circle replication by hybridizing with target nucleic acid DNA, which has the advantages of simplicity, rapidity and high amplification efficiency. RCA technology has been widely used in the field of biological analysis, especially in the field of sensor detection and cell imaging analysis of nucleic acid, protein, exosome, virus and other disease biomarkers. In this paper, the basic principles and classification of RCA technology are introduced, the research progress of RCA technology in the field of biosensing and cell imaging in recent years is systematically reviewed, and the shortcomings and improvement strategies of RCA technology are proposed.

Emi2 enables centriole amplification during multiciliated cell differentiation.

Massive centriole amplification during multiciliated cell (MCC) differentiation is a notable example of organelle biogenesis. This process is thought to be enabled by a derived cell cycle state, but the key cell cycle components required for centriole amplification in MCC progenitors remain poorly defined. Here, we show that emi2 (fbxo43) expression is up-regulated and acts in MCC progenitors after cell cycle exit to transiently inhibit anaphase-promoting complex/cyclosome (APC/C)cdh1 activity. We find that this inhibition is required for the phosphorylation and activation of a key cell cycle kinase, plk1, which acts, in turn, to promote different steps required for centriole amplification and basal body formation, including centriole disengagement, apical migration, and maturation into basal bodies. This emi2-APC/C-plk1 axis is also required to down-regulate gene expression essential for centriole amplification after differentiation is complete. These results identify an emi2-APC/C-plk1 axis that promotes and then terminates centriole assembly and basal body formation during MCC differentiation.

Multiple genetic paths including massive gene amplification allow Mycobacterium tuberculosis to overcome loss of ESX-3 secretion system substrates

Mycobacterium tuberculosis (Mtb) possesses five type VII secretion systems (T7SS), virulence determinants that include the secretion apparatus and associated secretion substrates. Mtb strains deleted for the genes encoding substrates of the ESX-3 T7SS, esxG or esxH, require iron supplementation for invitro growth and are highly attenuated invivo. In a subset of infected mice, suppressor mutants of esxG or esxH deletions were isolated, which enabled growth to high titers or restored virulence. Suppression was conferred by mechanisms that cause overexpression of an ESX-3 paralogous region that lacks genes for the secretion apparatus but encodes EsxR and EsxS, apparent ESX-3 orphan substrates that functionally compensate for the lack of EsxG or EsxH. The mechanisms include the disruption of a transcriptional repressor and a massive 38- to 60-fold gene amplification. These data identify an iron acquisition regulon, provide insight into T7SS, and reveal a mechanism of Mtb chromosome evolution involving "accordion-type" amplification.

Massive amplification of photoluminescence and exceptional water stability of MAPbBr3nanocrystals through core–shell nanostructure formation in a self-defence mechanism

Vulnerability to atmospheric conditions and their associated toxicity limit the practical/industrial use of perovskites despite their tremendous promise in optoelectronics.

Rapid evolutionary dynamics of an expanding family of meiotic drive factors and their hpRNA suppressors.

Meiotic drivers are a class of selfish genetic elements whose existence is frequently hidden due to concomitant suppressor systems. Accordingly, we know little of their evolutionary breadth and molecular mechanisms. Here, we trace the evolution of the Dox meiotic drive system in Drosophila simulans, which affects male-female balance (sex-ratio). Dox emerged via stepwise mobilization and acquisition of multiple D. melanogaster gene segments including from protamine, which mediates compaction of sperm chromatin. Moreover, we reveal novel Dox homologs and massive amplification of Dox superfamily genes on X chromosomes of its closest sisters D. mauritiana and D. sechellia. Emergence of Dox loci is tightly associated with 359-class satellite repeats that flank de novo genomic copies. In concert, we find coordinated diversification of autosomal hairpin RNA-class siRNA loci that target subsets of Dox superfamily genes. Overall, we reveal fierce genetic arms races between meiotic drive factors and siRNA suppressors associated with recent speciation.

Liquid Biopsy and Lymphoma Monitoring in Clinical Practice

INTRODUCTIONLymphomas represent the fourth most frequent type of cancer, 90% of them arising from B cell lymphocytes. Despite their high prevalence, around 40% remain incurable because of refractoriness to current chemoimmunotherapy or disease relapse after obtaining response (Li et al., 2018; Meng et al., 2020). The cell of origin is a B lymphocyte with a unique B cell receptor (BCR). The BCR is an immunoglobulin composed of two heavy chains (IgH) and two light chains (IgL) whose genes have multiple coding segments that through rearrangement first and further somatic hypermutation in the germinal center, generate a unique sequence that could be used to monitor the treatment response (Seifert et al., 2019; Wang et al., 2020). This project studies the use of next-generation sequencing (NGS) to characterize and monitor such IgH clonality. The use of liquid biopsy samples would provide a minimally invasive method to identify refractory or relapse-risk patients since all of them will have residual tumor cells after treatment.METHODSThe sample size of the study was 53 patients with several types of B-cell lymphomas. The IgH gene of the tumor clone was characterized from DNA of tumor samples at diagnosis by NGS and Sanger. The monitoring of this clone was studied by NGS from DNA and circulating tumor nucleic acids (ctNAs) during and after receiving treatment and at different times after clinical response was stablished (CR or PR). Relapse samples were analyzed by NGS and Sanger.RESULTSCharacterization of the tumor clone IgH rearrangement is achieved in 45 of the 53 patients with B-cell lymphoma included in the study. As shown in Figure 1, after the two different amplification PCRs results are similar. In contrast, after sequencing the results obtained by Sanger and NGS are very different. In NGS, thanks to the massive amplification prior to sequencing, it is identify the tumor clone in approximately 80% of the samples. It is shown that the effectiveness in characterization is dependent on the origin of the DNA sample, with fresh material samples being the optimal (Figure 1).In monitoring, samples of different origin are used as shown in Figure 2. About 50% of these samples are plasma ctNAs whose average efficiency in the detection of IgH gene rearrangement is 73.3%, with a clear positive correlation between the sensitivity and the toal volume of plasma processed more starting plasma used (2 mL efficiency of 84.09%).Monitoring makes it possible to classify patients into three different groups (Figure 3): patients with complete remission, patients refractory to the different lines of treatment and patients with apparent complete response and subsequent relapse. In patients with complete response, the tumor clone decreases during treatment and at the end of the line it is no longer detectable, nor in subsequent follow-up samples. With respect to refractory patients, it is observed that the tumor clone remains present despite subsequent lines of treatment. Finally, in patients achieving CR with subsequent relapse, the clone can be detected in a small percentage at the end of the treatment schedule and remains present until relapse.A section of patients under treatment is also shown (Figure 3) to demonstrate the application of the study to clinical practice. Two patients with apparent complete response, one of them in complete remission and the other with a high risk of relapse, requiring a more exhaustive follow-up.The monitoring results obtained by flow cytometry are shown being these, in general, concordant. In some cases NGS shows greater sensitivity.CONCLUSIONThe use of NGS and liquid biopsy samples provides a minimally invasive method to monitor the IgH gene rearrangement of the tumor clone of patients with B-cell lymphomas. In our experience, patients in remission can be clearly differentiated from those who are refractory or at risk of relapse. facilitating their treatment strategy and clinical decision making. [Display omitted] DisclosuresFerrer Lores: Janssen: Membership on an entity's Board of Directors or advisory committees. Terol: BMS: Consultancy; Hospital Clinico Valencia: Current Employment; Roche: Consultancy; Gilead: Consultancy, Membership on an entity's Board of Directors or advisory committees, Other: Travel, Research Funding; Roche: Membership on an entity's Board of Directors or advisory committees, Other: Travel; Janssen: Membership on an entity's Board of Directors or advisory committees, Other: Travel, Research Funding; Takeda: Membership on an entity's Board of Directors or advisory committees, Other: Travel; Abbvie: Consultancy, Membership on an entity's Board of Directors or advisory committees, Other: Travel.

The Formation of Neochromosomes during Experimental Evolution in the Yeast Saccharomyces cerevisiae.

Novel, large-scale structural mutations were previously discovered during the cultivation of engineered Saccharomyces cerevisiae strains in which essential tRNA synthetase genes were replaced by their orthologs from the distantly related yeast Yarrowia lipolytica. Among those were internal segmental amplifications forming giant chromosomes as well as complex segmental rearrangements associated with massive amplifications at an unselected short locus. The formation of such novel structures, whose stability is high enough to propagate over multiple generations, involved short repeated sequences dispersed in the genome (as expected), but also novel junctions between unrelated sequences likely triggered by accidental template switching within replication forks. Using the same evolutionary protocol, we now describe yet another type of major structural mutation in the yeast genome, the formation of neochromosomes, with functional centromeres and telomeres, made of extra copies of very long chromosomal segments ligated together in novel arrangements. The novel junctions occurred between short repeated sequences dispersed in the genome. They first resulted in the formation of an instable neochromosome present in a single copy in the diploid cells, followed by its replacement by a shorter, partially palindromic neochromosome present in two copies, whose stability eventually increased the chromosome number of the diploid strains harboring it.

Synthetic liver fibrotic niche extracts achieve in vitro hepatoblasts phenotype enhancement and expansion

SummaryIt is still a challenge for synthesizing ‘cellular niche-mimics’ in vitro with satisfactory reproducibility and fidelity to recreate the natural niche components (e.g., extracellular matrices and soluble factors) for stem cell cultivation. Inspired by the massive amplification of hepatic progenitor cells during liver fibrosis in vivo, here we optimized the in vitro liver fibrotic niches and subsequently harvested their bioactive ingredients as niche extracts (NEs). The fibrosis-relevant NE marginally outperformed Matrigel for phenotype maintenance of human embryonic stem cell (hESC)-derived hepatoblasts (HBs) and recapitulation of the pathological angiogenesis of hESC-derived endothelial cells both in 2D culture and 3D liver organoids. Finally, defined NE components (i.e., collagen III, IV, IL-17, IL-18 and M-CSF) were resolved by the quantitative proteomics which exhibited advantage over Matrigel for multi-passaged HB expansion. The pathology-relevant and tissue-specific NEs provide innovative and generalizable strategies for the discovery of optimal cellular niche and bioactive niche compositions.

Genomic Differences Between the Sexes in a Fish Species Seen Through Satellite DNAs

Neotropical fishes have highly diversified karyotypic and genomic characteristics and present many diverse sex chromosome systems, with various degrees of sex chromosome differentiation. Knowledge on their sex-specific composition and evolution, however, is still limited. Satellite DNAs (satDNAs) are tandemly repeated sequences with pervasive genomic distribution and distinctive evolutionary pathways, and investigating satDNA content might shed light into how genome architecture is organized in fishes and in their sex chromosomes. The present study investigated the satellitome of Megaleporinus elongatus, a freshwater fish with a proposed Z1Z1Z2Z2/Z1W1Z2W2 multiple sex chromosome system that encompasses a highly heterochromatic and differentiated W1 chromosome. The species satellitome comprises of 140 different satDNA families, including previously isolated sequences and new families found in this study. This diversity is remarkable considering the relatively low proportion that satDNAs generally account for the M. elongatus genome (around only 5%). Differences between the sexes in regards of satDNA content were also evidenced, as these sequences are 14% more abundant in the female genome. The occurrence of sex-biased signatures of satDNA evolution in the species is tightly linked to satellite enrichment associated with W1 in females. Although both sexes share practically all satDNAs, the overall massive amplification of only a few of them accompanied the W1 differentiation. We also investigated the expansion and diversification of the two most abundant satDNAs of M. elongatus, MelSat01-36 and MelSat02-26, both highly amplified sequences in W1 and, in MelSat02-26’s case, also harbored by Z2 and W2 chromosomes. We compared their occurrences in M. elongatus and the sister species M. macrocephalus (with a standard ZW sex chromosome system) and concluded that both satDNAs have led to the formation of highly amplified arrays in both species; however, they formed species-specific organization on female-restricted sex chromosomes. Our results show how satDNA composition is highly diversified in M. elongatus, in which their accumulation is significantly contributing to W1 differentiation and not satDNA diversity per se. Also, the evolutionary behavior of these repeats may be associated with genome plasticity and satDNA variability between the sexes and between closely related species, influencing how seemingly homeologous heteromorphic sex chromosomes undergo independent satDNA evolution.

Enhanced transport of ions by tuning surface properties of the nanochannel.

Motivated by recent observations of anomalously large deviations of the conductivity currents in confined systems from the bulk behavior, we revisit the theory of ion transport in parallel-plate channels and also discuss how the wettability of a solid and the mobility of adsorbed surface charges impact the transport of ions. It is shown that depending on the ratio of the electrostatic disjoining pressure to the excess osmotic pressure at the walls two different regimes occur. In the thick channel regime this ratio is small and the channel effectively behaves as thick, even when the diffuse layers strongly overlap. The latter is possible for highly charged channels only. In the thin channel regime the disjoining pressure is comparable to the excess osmotic pressure at the wall, which implies relatively weakly charged walls. We derive simple expressions for the mean conductivity of the channel in these two regimes, highlighting the role of electrostatic and electrohydrodynamic boundary conditions. Our theory provides a simple explanation of the high conductivity observed experimentally in hydrophilic channels, and allows one to obtain rigorous bounds on its attainable value and scaling with salt concentration. Our results also show that further dramatic amplification of conductivity is possible if hydrophobic slip is involved, but only in the thick channel regime provided the walls are sufficiently highly charged and most of the adsorbed charges are immobile. However, for weakly charged surfaces the massive conductivity amplification due to hydrodynamic slip is impossible in both regimes. Interestingly, in this case the moderate slip-driven contribution to conductivity can monotonously decrease with the fraction of immobile adsorbed charges. These results provide a framework for tuning the conductivity of nanochannels by adjusting their surface properties and bulk electrolyte concentrations.

Rare transposable elements challenge the prevailing view of transposition dynamics in plants.

Transposable elements (TEs) in plants are best known for their ability to inflate genome size and their potential effects on host phenotypes. In this essay, we suggest that many TEs do none of these things, but survive and replicate inconspicuously in the host genome. Transposable elements are frequently depicted as “invasive” sequences with a tendency to replicate in “bursts” as soon as the silencing mechanisms keeping them in check are relaxed. While massive amplifications do occur and have intriguing consequences, this way of thinking about TEs, guided by analogies from horizontally transmitted pathogens, can be misleading. By means of the example of Alesia elements—a retrotransposon lineage present at low copy numbers throughout angiosperms—we propose a scenario of vertical descent in which TEs are maintained in evolution not because of their ability to invade and amplify, but because they have evolved strategies to persist at low copy numbers. Studying the adaptive traits of rare TEs across species promises intriguing insights into the world of intragenomic conflict and a more nuanced view of transposition dynamics in plants.

Massive Pressure Amplification by Stimulated Contraction of Mesoporous Frameworks*.

Herein we demonstrate mesoporous frameworks interacting with carbon dioxide leading to stimulated structural contractions and massive out‐of‐equilibrium pressure amplification well beyond ambient pressure. Carbon dioxide, a non‐toxic and non‐flammable working medium, is promising for the development of pressure‐amplifying frameworks for pneumatic technologies and safety systems. The strong interaction of the fluid with the framework even contracts DUT‐46, a framework hitherto considered as non‐flexible. Synchrotron‐based in situ PXRD/adsorption experiments reveal the characteristic contraction pressure for DUT‐49 pressure amplification in the range of 350–680 kPa. The stimulated framework contraction expels 1.1 to 2.4 mmol g−1 CO2 leading to autonomous pressure amplification in a pneumatic demonstrator system up to 428 kPa. According to system level estimations even higher theoretical pressure amplification may be achieved between 535 and 1011 kPa.

Massive Pressure Amplification by Stimulated Contraction of Mesoporous Frameworks**

AbstractHerein we demonstrate mesoporous frameworks interacting with carbon dioxide leading to stimulated structural contractions and massive out‐of‐equilibrium pressure amplification well beyond ambient pressure. Carbon dioxide, a non‐toxic and non‐flammable working medium, is promising for the development of pressure‐amplifying frameworks for pneumatic technologies and safety systems. The strong interaction of the fluid with the framework even contracts DUT‐46, a framework hitherto considered as non‐flexible. Synchrotron‐based in situ PXRD/adsorption experiments reveal the characteristic contraction pressure for DUT‐49 pressure amplification in the range of 350–680 kPa. The stimulated framework contraction expels 1.1 to 2.4 mmol g−1 CO2 leading to autonomous pressure amplification in a pneumatic demonstrator system up to 428 kPa. According to system level estimations even higher theoretical pressure amplification may be achieved between 535 and 1011 kPa.

Non-Invasive Evaluation of Acute Effects of Tubulin Binding Agents: A Review of Imaging Vascular Disruption in Tumors.

Tumor vasculature proliferates rapidly, generally lacks pericyte coverage, and is uniquely fragile making it an attractive therapeutic target. A subset of small-molecule tubulin binding agents cause disaggregation of the endothelial cytoskeleton leading to enhanced vascular permeability generating increased interstitial pressure. The resulting vascular collapse and ischemia cause downstream hypoxia, ultimately leading to cell death and necrosis. Thus, local damage generates massive amplification and tumor destruction. The tumor vasculature is readily accessed and potentially a common target irrespective of disease site in the body. Development of a therapeutic approach and particularly next generation agents benefits from effective non-invasive assays. Imaging technologies offer varying degrees of sophistication and ease of implementation. This review considers technological strengths and weaknesses with examples from our own laboratory. Methods reveal vascular extent and patency, as well as insights into tissue viability, proliferation and necrosis. Spatiotemporal resolution ranges from cellular microscopy to single slice tomography and full three-dimensional views of whole tumors and measurements can be sufficiently rapid to reveal acute changes or long-term outcomes. Since imaging is non-invasive, each tumor may serve as its own control making investigations particularly efficient and rigorous. The concept of tumor vascular disruption was proposed over 30 years ago and it remains an active area of research.