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Cancer, which is often described as an uncontrollable rapid proliferation of cells, is currently the leading cause of death in the world together with cardiac disease. Therefore, the main purpose of the current research work was to study the anticancer effects of a first-time-synthesized phthalocyanine (Pc) as photosensitizer in PDT against cancer and evaluate its effects on human cells in vitro. Quantum yields of singlet oxygen photogeneration were in air using the relative method with standard-ZnPc as reference and DPBF as chemical quencher for singlet oxygen. The concentration of DPBF was prepared almost 3 x 10-5 molar to avoid chain reactions induced by DPBF in the presence of singlet oxygen. Solutions of Pc as sensitizer (absorbance = 2.0 at the irradiation wavelength) containing DPBF were prepared in the dark and irradiated in the Q band region using the setup described. DPBF degradation at 417 nm was monitored with UV-Vis spectrophotometry. For in vitro studies, nine different MFPc-1 concentrations (0.2 µM- 0.4 µM- 0.8 µM- 1.6 µM- 3.2 µM- 6.4 µM- 12.8 µM- 25.6 µM- 51.2 µM) applied to MCF-7 and MDA-MB-231 breast cancer cell lines for 24 hours and MTT assay was carried out. After determination of optimum concentration, mitotic index, and apoptotic index values of cell lines were determined with administration of these concentrations. Singlet oxygen quantum yield (Φ), which is a measure of the efficiency, of MFPc-1 was found 0.50, although MFPc-1 is being metal-free phthalocyanine. For in vitro studies after the application of different concentrations to MCF-7 and MDA-MB-231 for 24 hours, the optimum concentration was determined as 12 µM for both cell lines by the MTT assay. After application of the determined optimum concentration for 24, 48 and 72 hours, there was a significant decrease in the mitotic index values and significant increase in the apoptotic index values of both MCF-7 and MDA-MB-231 breast cancer cell lines.

BACKGROUND: We previously reported that CEA kinetics are a marker of progressive disease (PD) in metastatic colorectal cancer (mCRC). This study was specifically designed to confirm CEA kinetics for predicting PD and to evaluate CA19-9, cell-free DNA (cfDNA), circulating tumour DNA (ctDNA) and circulating tumour cell (CTC) kinetics. METHODS: Patients starting a chemotherapy (CT) with pre-treatment CEA > 5 ng/mL and/or CA19.9 > 30 UI/mL were prospectively included. Samples were collected from baseline to cycle 4 for CEA and CA19-9 and at baseline and the sixth week for other markers. CEA kinetics were calculated from the first to the third or fourth CT cycle. RESULTS: A total of 192 mCRC patients were included. CEA kinetics based on the previously identified >0.05 threshold was significantly associated with PD (p

In recent years, interest in the possible molecular regulators of cell proliferation and differentiation in a wide range of regeneration models has grown significantly, but the cell kinetics of this process remain largely a mystery. Here we try to elucidate the cellular aspects of regeneration by EdU incorporation in intact and posteriorly amputated annelid Alitta virens using quantitative analysis. We found that the main mechanism of blastema formation in A. virens is local dedifferentiation; mitotically active cells of intact segments do not significantly contribute to the blastemal cellular sources. Amputation-induced proliferation occurred predominantly within the epidermal and intestinal epithelium, as well as wound-adjacent muscle fibers, where clusters of cells at the same stage of the cell cycle were found. The resulting regenerative bud had zones of high proliferative activity and consisted of a heterogeneous population of cells that differed in their anterior–posterior positions and in their cell cycle parameters. The data presented allowed for the quantification of cell proliferation in the context of annelid regeneration for the first time. Regenerative cells showed an unprecedentedly high cycle rate and an exceptionally large growth fraction, making this regeneration model especially valuable for studying coordinated cell cycle entry in vivo in response to injury.

In this current study, antiproliferative effect of Hec1/Nek2 Mitotic Pathway inhibitor INH1 was investigated in adenocarcinomic human alveolar basal epithelial cells A549 and human cervix carcinoma HeLa cell lines in vitro. To this end cell index values by xCELLigence Real‐Time Cell Analysis DP instrument, mitotic index, BrdU proliferation assay and apoptotic index analysis were used. The results of the current study showed that INH1 had cytostatic and cytoskeletal effects on A549 and cytostatic effect on HeLa cells. The IC50 concentration was determined as 56 µM with the xCelligence device for both cell lines. IC50 concentration was used for all other parameters. While this concentration decreased the mitotic index BrdU proliferation values, it increased the apoptotic index values of both of cell lines. There were significant differences between the control and the experimental groups (p

The paper deals with applying mathematical modeling to study tumor growth process and optimizing cancer treatment. A structured review of the studies devoted to this problem is given. The role of the cell life cycle in understanding the tumor growth and the mechanisms of cancer treatment is discussed. It is important that modern cancer treatment methods, in particular, chemotherapy and radiation therapy, affect both normal and tumor cells in certain stages of the life cycle and do not influence on cells in other stages. Cell life cycle description is given as well as the mechanisms that maintain and restore normal density of the cell population. A graph of cell life cycle stages and transitions is demonstrated. Dynamic mathematical model of proliferative homeostasis in the cell population is proposed, which takes into account the heterogeneity of cell populations by life cycle stages. The model is a system of differential equations with delays. The stationary state of the model is investigated, which allows to determine the parameters values for the normal cell population. The results of a numeric experiment is obtained, which is focused on the process of cell population density recovery after mass death of cells. As the experiment shows, after cell death, the densities of cells in different life cycle stages are restored to normal values, which corresponds to the concepts of proliferative homeostasis in cell populations.

Neurogenesis in the adult brain, a powerful mechanism for neuronal plasticity and brain repair, is altered by aging and pathological conditions, including metabolic disorders. The search for mechanisms and therapeutic solutions to alter neurogenesis requires understanding of cell kinetics within neurogenic niches using a high-throughput quantitative approach. The challenge is in the dynamic nature of the process and multiple cell types involved, each having several potential modes of division or cell fate. Here we show that cell kinetics can be revealed through a combination of the BrdU/EdU pulse-chase, based on the circadian pattern of DNA replication, and a differential equations model that describes time-dependent cell densities. The model is validated through the analysis of cell kinetics in the cerebellar neurogenic niche of normal young adult male zebrafish, with cells quantified in 2D (sections), and with neuronal fate and reactivation of stem cells confirmed in 3D whole-brain images (CLARITY). We then reveal complex alterations in cell kinetics associated with accelerated aging due to chronic high caloric intake. Low activity of neuronal stem cells in this condition persists 2 months after reverting to normal diet, and is accompanied by overproduction of transient amplifying cells, their accelerated cell death, and slow migration of postmitotic progeny. This combined experimental and mathematical approach should allow for relatively high-throughput analysis of early signs of pathological and age-related changes in neurogenesis, evaluation of specific therapeutic targets, and drug efficacy.SIGNIFICANCE STATEMENTUnderstanding normal cell kinetics of adult neurogenesis and the type of cells affected by a pathological process is needed to develop effective prophylactic and therapeutic measures directed at specific cell targets. Complex time-dependent mechanisms involved in the kinetics of multiple cell types require a combination of experimental and mathematical modeling approaches. This study demonstrates such a combined approach by comparing normal neurogenesis with that altered by diet-induced accelerated aging in adult zebrafish.

Auxin is a key regulator of plant growth and development. Local auxin biosynthesis and intercellular transport generates regional gradients in the root that are instructive for processes such as specification of developmental zones that maintain root growth and tropic responses. Here we present a toolbox to study auxin-mediated root development that features: (i) the ability to control auxin synthesis with high spatio-temporal resolution and (ii) single-cell nucleus tracking and morphokinetic analysis infrastructure. Integration of these two features enables cutting-edge analysis of root development at single-cell resolution based on morphokinetic parameters under normal growth conditions and during cell-type-specific induction of auxin biosynthesis. We show directional auxin flow in the root and refine the contributions of key players in this process. In addition, we determine the quantitative kinetics of Arabidopsis root meristem skewing, which depends on local auxin gradients but does not require PIN2 and AUX1 auxin transporter activities. Beyond the mechanistic insights into root development, the tools developed here will enable biologists to study kinetics and morphology of various critical processes at the single cell-level in whole organisms., Auxin gradients regulate plant root growth and development. Here the authors manipulate auxin synthesis in specific root cell types and use single-cell nucleus tracking and morphokinetics to map directional auxin flow in the root and quantify the kinetics of meristem skewing.

International audience; Among endocrine organs, ovaries are unique because their function is supported by an ever-changing number of histological entities, the ovarian follicles, which are themselves subject to asynchronous development from their formation up to ovulation. Follicle development combines finely controlled processes of cell dynamics with original morphogenesis steps. Understanding the dynamics of follicle populations, on the whole ovary level, and the coupled dynamics of the oocyte and somatic cells, on the follicle level, is crucial to understand ovarian physiology and ovarian aging. Mathematical modeling studies combined with proper experimental approaches can be particularly helpful for gaining insight into follicle dynamics on different scales.

Myelosuppression is one of the most common and severe adverse events associated with anti-cancer therapies and can be a source of drug attrition. Current mathematical modeling methods for assessing cytopenia risk rely on indirect measurements of drug effects and primarily focus on single lineage responses to drugs. However, anti-cancer therapies have diverse mechanisms with varying degrees of effect across hematopoietic lineages. To improve predictive understanding of drug-induced myelosuppression, we developed a quantitative systems pharmacology (QSP) model of hematopoiesis in vitro for quantifying the effects of anti-cancer agents on multiple hematopoietic cell lineages. We calibrated the system parameters of the model to cell kinetics data without treatment and then validated the model by showing that the inferred mechanisms of anti-proliferation and/or cell-killing are consistent with the published mechanisms for three classes of drugs with different mechanisms of action. Using a set of compounds as a reference set, we then analyzed novel compounds to predict their mechanisms and magnitude of myelosuppression. Further, these quantitative mechanisms are valuable for the development of translational in vivo models to predict clinical cytopenia effects., Author summary Reduced bone marrow activity and levels of mature blood cells is an undesirable side effect of many anti-cancer therapies. Selecting promising lead compounds for further development requires understanding of potential myelosuppressive effects. However, existing preclinical experiments and modeling formulations fail to consider drug effects on multiple blood cell types or the mechanistic differences between how drugs induced myelosuppression. Here we developed a quantitative systems pharmacology (QSP) model that estimates a drug candidate’s effect on multiple precursor and mature blood cell lineages and further distinguishes how the drug affects these populations—through cell-killing or anti-proliferation mechanisms. This modeling formalism is valuable for vetting compounds for therapeutic development and for further translational modeling to anticipate the clinical effects of compounds.

Vitamin D is widely known to regulate bone health, but there is increasing evidence that it may also ameliorate colitis through inflammation, cell proliferation and apoptosis, and the microbiota. The purpose of this review is to systematically examine the mechanisms by which vitamin D reduces colitis. PubMed and Web of Science were searched for articles published between 2008 and 2019 using key words such as “vitamin D,” “colitis,” “inflammatory bowel disease,” “inflammation,” “apoptosis,” “cell proliferation,” and “gut bacteria”. Retrieved articles were further narrowed and it was determined whether their title and abstracts contained terminology pertaining to vitamin D in relation to colitis in human clinical trials, animal studies, and cell culture/biopsy studies, as well as selecting the best match sorting option in relation to the research question. In total, 30 studies met the established criteria. Studies consistently reported results showing that vitamin D supplementation can downregulate inflammatory pathways of COX-2, TNF-α, NF-κB, and MAPK, modify cell kinetics, and alter gut microbiome, all of which contribute to an improved state of colitis. Although vitamin D and vitamin D analogs have demonstrated positive effects against colitis, more randomized, controlled human clinical trials are needed to determine the value of vitamin D as a therapeutic agent in the treatment of colitis.

This is a brief overview of the ideas of the possibility of using the cell kinetic model developed by the author in the 1980s to test, in experiments on cell cultures, potential geroprotectors and geropromoters that slow down or accelerate, respectively, the aging process in animals and humans. The history of the evolution of this model—from estimation of only the cell reproduction rate and saturation density in a non-subcultured cell culture to constructing survival curves in the stationary phase of growth and to a further analysis of the possible interrelation between all parts of the curve of cells’ growth and subsequent dying out—is considered. Possible approaches to mathematical and statistical analysis of the data obtained within the framework of this model system are analyzed. It is emphasized that such studies can be carried out on cells of a very different nature (normal and transformed human and animal cells, plant cells, yeast, mycoplasmas, bacteria, etc.), which makes possible an evolutionary approach to the interpretation of the results obtained. At the same time, in the author’s opinion, the most promising experiments are those carried out on immortalized cells of humans and animals, since they are not cancerous on the one hand and have an unlimited mitotic potential on the other hand and, therefore, do not “age” in the process of numerous divisions, as, for example, normal human diploid fibroblasts do. It is assumed that the appropriate mathematical analysis of the entire growth and dying out curve of a non-subcultured cell culture (from seeding into a culture flask to the complete death of all cells) may allow the clarification of certain relationships between the development and aging of a multicellular organism and to increase the reliability of identifying promising geroprotectors.

A new generation of heterobifunctional small molecules, termed proteolysis targeting chimeras (PROTACs), targets proteins for degradation through recruitment to E3 ligases and holds significant therapeutic potential. Despite numerous successful examples, PROTAC small molecule development remains laborious and unpredictable, involving testing compounds for end-point degradation activity at fixed times and concentrations without resolving or optimizing for the important biological steps required for the process. Given the complexity of the ubiquitin proteasomal pathway, technologies that enable real-time characterization of PROTAC efficacy and mechanism of action are critical for accelerating compound development, profiling, and improving guidance of chemical structure-activity relationship. Here, we present an innovative, modular live-cell platform utilizing endogenous tagging technologies and apply it to monitoring PROTAC-mediated degradation of the bromodomain and extra-terminal family members. We show comprehensive real-time degradation and recovery profiles for each target, precisely quantifying degradation rates, maximal levels of degradation ( D

Electrochemical metallization (ECM) cell kinetics are strongly determined by the electrolyte and can hardly be altered after the cell has been fabricated. Solid-state property tunable electrolytes in response to external stimuli are therefore desirable to introduce additional operational degree of freedom to the ECM cells, enabling novel applications such as multistate memory and reconfigurable computation. In this work, we use Ge2Sb2Te5(GST) as the electrolyte material whose solid state is switched from the amorphous(a) to the crystalline(c) phase thermally. Electrical heating too is readily achievable. The resistive switching characteristics of the cells with different GST phases are examined. The magnitude of the high resistance, the SET voltage and the on/off ratio are found to be considerably affected by the solid phase of GST, whereas the magnitude of the low resistance is least affected. Moreover, a transition from volatile to nonvolatile SET switching is only observed for c-GST based cell under prolonged voltage sweep, but not for a-GST based cell. This work provides a springboard for more studies on the manipulation of the ECM cell kinetics by tunable electrolyte and the resulting unprecedented device functionalities.

Digital holographic cytometry (DHC) permits label-free visualization of adherent cells. Dozens of cellular features can be derived from segmentation of hologram-derived images. However, the accuracy of single cell classification by these features remains limited for most applications, and lack of standardization metrics has hindered independent experimental comparison and validation. Here we identify twenty-six DHC-derived features that provide biologically independent information across a variety of mammalian cell state transitions. When trained on these features, machine-learning algorithms achieve blind single cell classification with up to 95% accuracy. Using classification accuracy to guide platform optimization, we develop methods to standardize holograms for the purpose of kinetic single cell cytometry. Applying our approach to human melanoma cells treated with a panel of cancer therapeutics, we track dynamic changes in cellular behavior and cell state over time. We provide the methods and computational tools for optimizing DHC for kinetic single adherent cell classification.

Choanoflagellates are common members of planktonic communities. Some have complex life histories that involve transitions between multiple cell stages. We have grown the loricate choanoflagellate Diaphanoeca grandis on the bacterium Pantoea sp. and integrated kinetic observations at the culture level and at the single cell level. The life history of D. grandis includes a cell division cycle with a number of recognisable cell stages. Mature, loricate D. grandis were immobile and settled on the bottom substratum. Daughter cells were ejected from the lorica 30 min. after cell division, became motile and glided on the bottom substratum until they assembled a lorica. Single cell kinetics could explain overall growth kinetics in D. grandis cultures. The specific growth rate was 0.72 day−1 during exponential growth while mature D. grandis produced daughter cells at a rate of 0.9 day−1. Daughter cells took about 1.2 h to mature. D. grandis was able to abandon and replace its lorica, an event that delayed daughter cell formation by more than 2 days. The frequency of daughter cell formation varied considerably among individuals and single cell kinetics demonstrated an extensive degree of heterogeneity in D. grandis cultures, also when growth appeared to be balanced.

We consider the Neumann problem for a coupled chemotaxis-haptotaxis model of cancer invasion with/without kinetic source in a 2D bounded and smooth domain. For a large class of cell kinetic sources including zero source and sub-logistic sources, we detect an explicit condition involving the chemotactic strength, the asymptotic "damping" rate, and the initial mass of cells to ensure uniform-in-time boundedness for the corresponding Neumann problem. Our finding significantly improves existing 2D global existence and boundedness in related chemotaxis-/haptotaxis systems., 29 pages. To appear in Nonlinearity, 2019

A state-of-the-art in vitro to in silico animal body simulation successfully predicts biodistribution with cellular resolution., Smart drug design for antibody and nanomaterial-based therapies allows optimization of drug efficacy and more efficient early-stage preclinical trials. The ideal drug must display maximum efficacy at target tissue sites, with transport from tissue vasculature to the cellular environment being critical. Biological simulations, when coupled with in vitro approaches, can predict this exposure in a rapid and efficient manner. As a result, it becomes possible to predict drug biodistribution within single cells of live animal tissue without the need for animal studies. Here, we successfully utilized an in vitro assay and a computational fluid dynamic model to translate in vitro cell kinetics (accounting for cell-induced degradation) to whole-body simulations for multiple species as well as nanomaterial types to predict drug distribution into individual tissue cells. We expect this work to assist in refining, reducing, and replacing animal testing, while providing scientists with a new perspective during the drug development process.

Length-dependent activation (LDA) of contraction is an important mechanism of proper myocardial function that is often blunted in diseases accompanied by deficient contractility and impaired calcium homeostasis. We evaluated how the extent of LDA is related to the decreased force in healthy rat myocardium under negative inotropic conditions that affect the calcium cycle. The length-dependent effects on auxotonic twitch and Ca-transient were compared in isolated rat ventricular cardiomyocytes at room temperature (“25C”) and near-physiological temperature (“35C”) in normal Tyrode and at 25°C with thapsigargin-depleted sarcoplasmic reticulum (“25C + Thap”). At the slack length, a similar negative inotropy in “35C” and “25C + Thap” was accompanied by totally different changes in Ca-transient amplitude, time-to-peak, and time-to-decline from peak to 50% amplitude. End-systolic/end-diastolic tension-sarcomere length relationships were obtained for each individual cell, and the ratio of their slopes, the dimensionless Frank-Starling Gain index, was 2.32 ± 0.16, 1.78 ± 0.09, and 1.37 ± 0.06 in “25C,” “35C” and “25C + Thap,” respectively (mean ± S.E.M.). Ca-transient diastolic level and amplitude did not differ between “25C” and “35C” at any SL, but in “35C” it developed and declined significantly faster. In contrast, thapsigargin-induced depletion of SERCA2a significantly attenuated and retarded Ca-transient. The relative amount of Ca2+ utilized by troponin C, evaluated by the integral magnitude of a short-lived component of Ca-transient decline (“bump”), increased by ~25% per each 0.05 μm increase in SL in all groups. The kinetics of the Ca-TnC dissociation, evaluated by the bump time-to-peak, was significantly faster in “35C” and slower in “25C + Thap” vs. “25C” (respectively, 63.7 ± 5.3 and 253.6 ± 8.3% of the value in “25C,” mean ± S.E.M.). In conclusion, a similar inotropic effect can be observed in rat ventricular myocardium under totally different kinetics of free cytosolic calcium. The extent of LDA is not determined by actual peak systolic tension but is regulated by the level of peak systolic calcium and the kinetics of Ca-transient decline which, in turn, are governed by Ca-TnC dissociation and Ca2+ reuptake by the sarcoplasmic reticulum. Altogether, these findings constitute new evidence about the role of the length-dependent modulation of Ca2+ homeostasis in the mechanisms of calcium regulation of contraction and mechano-calcium feedback in the myocardium. © Copyright © 2019 Lookin and Protsenko. Russian Foundation for Basic Research, RFBR: 18-04-00572-a The study was carried out within the framework of the IIF UrB RAS theme No АААА-А18-118020590031-8, supported by RFBR (grant #18-04-00572-a) and by RF Government Act #211 of March 16, 2013 (agreement 02.A03.21.0006).

Drug-induced allergy (DIA), an unexpectedly triggered side effect of drugs used for therapeutic purposes, is a serious clinical issue that needs to be resolved because it interrupts the treatment of the primary disease. Since conventional allergy testing is insufficient to accurately predict the occurrence of DIA or to determine the drugs causing it, the development of diagnostic and predictive tools for allergic reactions is important. We demonstrated a novel method, termed high-sensitive allergy test (HiSAT), for the rapid diagnosis of allergy (within 1 hr; with true-positive diagnosis rates of 89% and 9% for patients with and without allergy-like symptoms, respectively). HiSAT analyzes the cell kinetics as an index against chemotactic factors in a patient’s serum, as different from the diagnosis using conventional methods. Once allergy has occurred, HiSAT can be used to determine the causative medicine using culture supernatants incubated with the subject’s lymphocytes and the test allergen. This test is more efficient (60%) than the lymphocyte transformation test (20%). Furthermore, in HiSAT, cell mobility significantly increases in a dose-dependent manner against supernatant incubated with lymphocytes from a subject with pollinosis collected at a time when the subject is without allergic symptoms and the antigen. The result demonstraed that HiSAT might be a promising method to rapidly diagnose DIA or to determine with high accuracy the antigen causing allergy.

In this paper we consider the following chemotaxis-growth system with nonlinear signal production and logistic source \begin{document}$ \begin{eqnarray*} \left\{ \begin{array}{llll} u_t = \Delta u-\chi\nabla\cdot( u\nabla v)+\lambda u-\mu u^{\alpha}, \quad x'>with homogeneous Neumann boundary conditions in the ball \begin{document}$ \Omega = B_R(0)\subset \mathbb{R}^n $\end{document} for \begin{document}$ n\geq 1 $\end{document} and \begin{document}$ R>0 $\end{document} , where \begin{document}$ \chi, \lambda, \mu>0 $\end{document} , \begin{document}$ \alpha>1 $\end{document} , and \begin{document}$ f $\end{document} is an appropriate regular function satisfying \begin{document}$ f(u)\geq ku^{\kappa} $\end{document} for all \begin{document}$ u\geq1, \kappa>0 $\end{document} with some constants \begin{document}$ k>0 $\end{document} . If the number \begin{document}$ \kappa $\end{document} and \begin{document}$ \alpha $\end{document} satisfy \begin{document}$ \begin{equation*} \kappa+1>\alpha\left(\frac{2}{n}+1\right), \end{equation*} $\end{document} then there exists appropriate initial data such that the corresponding solution \begin{document}$ (u, v) $\end{document} of the system blow up in finite time. This result extends the blow-up result of the chemotaxis model without logistic cell kinetics in [ 45 ]. Apparently, for the case \begin{document}$ \kappa = 1 $\end{document} , this provides a rigorous detection for blow-up of solution in spaces-dimensions three and four.

Using tritium-labeled thymidine histoautoradiography, the AgNOR staining technique and Ki67-MIB-1 immunohistochemistry to study cell kinetics, prostate cancer can be subdivided into slowly, moderately and rapidly proliferating tumors. These are important supplementary methods and prerequisites for a grading as low, intermediate and high-grade in addition to classical histology and cytology. Cytometry of DNA can confirm the cell kinetics of prostate cancer by detection of a predominance of diploid or aneuploid cell nuclei but should only be evaluated together with histological investigations. All histology-based analyses of cell kinetics encompass the classical highly and poorly differentiated glandular and cribriform patterns as well as solid undifferentiated structures and the various subcategories. The malignancy grading of prostate cancer can result from the summation of histological grading and cell kinetic analyses, as long as the named investigations are included. The future perspectives of individualized therapy options, including active surveillance in early low-grade and also for high-grade prostate cancer and new antihormonal treatment in advanced disease, may increasingly rely on tissue biomarkers and advanced technologies for whole genome analysis including next generation sequencing.

Background: Reticulocytes are immature red blood cells containing RNA remnants. Their population kinetics has been documented under various in vivo and in vitro conditions, including after storage of red blood cells in blood banks. The purpose of this study was to describe the influence of blood bank storage on the kinetics of reticulocyte disappearance by in vitro culturing. Method: Samples of reticulocyte-enriched fractions (Percoll density-gradient) were obtained over different storage times from six red blood cell units stored in additive solution-1 (AS-1). Reticulocyte fractions were then cultured in enriched media at 37 °C and analyzed by flow cytometry with thiazole orange taking into account hemolysis. Results: Density-gradient enriched reticulocyte fractions were obtain from standard red blood cell units with

Macrophage behavior is of great interest in response to tissue injury and promotion of regeneration. With increasing numbers of zebrafish reporter-based assays, new capabilities now exist to characterize macrophage migration, and their responses to biochemical cues, such as reactive oxygen species. Real time detection of macrophage behavior in response to oxidative stress using quantitative measures is currently beyond the scope of commercially available software solutions, presenting a gap in understanding macrophage behavior. To address this gap, we developed an image analysis pipeline solution to provide real time quantitative measures of cellular kinetics and reactive oxygen species content in vivo after tissue injury. This approach, termed Zirmi, differs from current software solutions that may only provide qualitative, single image analysis, or cell tracking solutions. Zirmi is equipped with user-defined algorithm parameters to customize quantitative data measures with visualization checks for an analysis pipeline of time-based changes. Moreover, this pipeline leverages open-source PhagoSight, as an automated keyhole cell tracking solution, to avoid parallel developments and build upon readily available tools. This approach demonstrated standardized space- and time-based quantitative measures of (1) fluorescent probe based oxidative stress and (2) macrophage recruitment kinetic based changes after tissue injury. Zirmi image analysis pipeline performed at execution speeds up to 10-times faster than manual image-based approaches. Automated segmentation methods were comparable to manual methods with a DICE Similarity coefficient > 0.70. Zirmi provides an open-source, quantitative, and non-generic image analysis pipeline. This strategy complements current wide-spread zebrafish strategies, for automated standardizations of analysis and data measures.

The restoration of the skin barrier in acute and chronic wounds is controlled by several molecular mechanisms that synergistically regulate cell kinetics, enzymatic functions, and neurovascular activation. These pathways include genetic and epigenetic activation, which modulate physiological wound healing. Our review describes the genetic background of skin repair, namely transcription-independent diffusible damage signals, individual variability, epigenetic mechanism, controlled qualitative traits, post-translational mechanisms, antioxidants, nutrients, DNA modifications, bacteria activation, mitochondrial activity, and oxidative stress. The DNA background modulating skin restoration could be used to plan new diagnostics and therapeutics.

International audience; The classic Luria-Delbrück model for fluctuation analysis is extended to the case where the split instant distributions of cells are not i.i.d.: the lifetime of each cell is assumed to depend on its birth date. This model takes also into account cell deaths and non exponentially distributed lifetimes. In particular, it is possible to consider subprobability distributions, and model non exponential growth. It leads to a family of probability distributions which depend on the expected number of mutations, the death probability of mutant cells, and the split instant distributions of normal and mutant cells. This is deduced from the Bellman-Harris integral equation, written for the birthdate inhomoge-neous case. A new theorem of convergence for the final mutant counts is proved, using an analytic method. Particular examples like the Haldane model, or the case where hazard functions of the split instant distributions are proportional are studied. The Luria-Delbrück distribution with cell deaths is recovered. A computation algorithm for the probabilities is provided.

Concepts in biology feed into general theories of growth, development and evolution of organisms and how they interact with the living and non-living components of their environment. A well-founded concept clarifies unsolved problems and serves as a focus for further research. One such example of a constructive concept in the plant sciences is that of the quiescent centre (QC). In anatomical terms, the QC is an inert group of cells maintained within the apex of plant roots. However, the evidence that established the presence of a QC accumulated only gradually, making use of strands of different types of observations, notably from geometrical-analytical anatomy, radioisotope labelling and autoradiography. In their turn, these strands contributed to other concepts: those of the mitotic cell cycle and of tissue-related cell kinetics. Another important concept to which the QC contributed was that of tissue homeostasis. The general principle of this last-mentioned concept is expressed by the QC in relation to the recovery of root growth following a disturbance to cell proliferation; the resulting activation of the QC provides new cells which not only repair the root meristem but also re-establish a new QC.

The aim of this study was to analyze cell kinetics through expression and apoptosis of topoisomerase 2-α (TOP2A), p53, and c-erb2 in rectosigmoid endometriotic lesions and in healthy endometrial tissue and to establish correlations between such findings and clinical data in patients with rectosigmoid endometriosis. Sixty patients with rectosigmoid endometriosis and 20 control women without endometriosis were included. Immunohistochemical assays were used to measure expression of TOP2A, p53, and c-erB-2. Apoptosis was quantified by directly counting the apoptotic bodies. The number of lesions was positively correlated with expression of TOP2A in the lesion. There was also significant correlation between the lesions’ size and number and cell turnover index. Apoptosis index (AI) was the same for endometriosis lesions and eutopic endometrium. Expression of TOP2A was significantly lower in the endometriosis group compared to the controls. Changes in cell proliferation but not in the AI in rectosigmoid endometriosis are indicative of an imbalance in cell kinetics that may lead to the development of the disease.

In this study, we aimed to investigate whether the procedure and product kinetics differ according to age groups in advanced-age MM patients who underwent autologous HSCT. 59 patients who underwent autologous HSCT were retrospectively analyzed. Then, the patients were divided into two groups as 60–65 years and ?65 years. It was significantly lower in ?65 years group (p = 0.008) and proportionally, the procedure duration was also significantly shortened in this group (p = 0.013). Total number of collected CD34 positive stem cells was 6.20 × 106 (±3.83) in 60–65 years group while it was 5.51 × 106 (±2.48) in ?65 years group with no statistically significant difference (p = 0.825). In conclusion, there was no significant difference in terms of the number of collected CD34-positive stem cells in this study that investigates the mobilization data, procedure and product kinetics, we think that successful stem cell mobilization can be performed in appropriately selected patients regardless of age. © 2018 Elsevier Ltd

We evaluated the effects of air pollution on the adrenal cortex using 30 female mice divided into two groups of fifteen animals each. One group was conditioned daily in a chamber with exposure to particulate matter (PM) 2.5 μm (GExp). Animals were exposed on daily basis in an ambient particles concentrator during the period of time enough to reach an accumulated dose of 600 μg/m3, which corresponds to a 24-h exposure of 25 μg/m3 that approximates to the annual mean of PM2.5 in Sao Paulo. The other group was allocated to another chamber with filtered air (GCrt). After euthanasia, the adrenals underwent histological processing and immunohistochemistry staining for Ki-67 and cleaved caspase-3. Histomorphometry of the adrenal glands in GExp showed increased thickness of the zona glomerulosa, while in GCrt; the adrenal glands from GExp had higher Ki-67 immunostaining scores in the zona reticularis than those from GCrt. The adrenal from GExp showed higher cleaved caspase-3 immunoreactivity in the zona f...

Aim of the study is to investigate the possibility to supplement the predictive ability of conventional statistics by taking into account the prognostic variables selected by automatic rule generation methods. The analysis involves patients affected by head and neck squamous cell carcinoma, treated by conventional radiotherapy, partly accelerated radiotherapy or combined chemo-radiotherapy. Univariate and multivariate statistic analysis are performed via SPSS, whereas the rule generation techniques considered are decision trees and logical neural networks. For each rule generation technique the prognostic variables are obtained by solving a proper classification problem (overall survival or loco-regional control) and by extracting a set of understandable rules underlying the problem at hand. Bayesian and neural networks are also used as a reference to evaluate the quality of the achieved accuracy. Conventional statistics selects as main predictive variables the dimension of the tumor, the involvement of lymphonodes, and the cancer site. Rule generation methods, besides extending similar results also to other candidate prognostic factors with reasonable accuracy, even when the number of available data is small, are also able to suggest non trivial rules linking the predictive factors.

Flow cytometry is a versatile technique to study different aspects of the cell cycle from subpopulations of cells to detailed cell kinetic information. In this paper a basic review of cell kinetic parameters is presented followed by detailed descriptions of the different flow cytometric methodologies that can be used to extract pertinent information for a particular study. The methodologies range from simple DNA profile analysis, the use of bromodeoxyuridine to cell cycle-associated proteins such as the cyclins.

Aim: Though odontogenic lesions have in common origin from the primitive odontogenic epithelium , there is a diversity in their initiation behavior and growth. The aggressive nature of odontogenic keratocyst similar to ameloblastoma in comparision with the other common odontogenic (dentigerous and radicular) cyst could be due to possible differences in their epithelial linings. PCNA (Proliferating cell nuclear antigen) is a cell cycle related antigen, used in the study of cell kinetics of these epithelial linings, to corelate the biological behaviour among these common odontogenic lesions. Objectives: This paper has intended to study the cell kinetics of 4 selected odontogenic lesions (dentigerous cyst, radicular cyst,odontogenic keratocyst and ameloblastoma) to demonstrate differences in their epithelial linings. Material and Methods: Sixty samples of paraffin embedded tissue specimens (archival tissues) were included (15 radicularcysts, 15 odontogenic keratocysts; 15 dentigerous cysts and15 Ameloblastoma. Results: Among cyst OKC had higher values than DC and RC. When staining results of all the cyst were compared individually with ameloblastoma ,the staining results of OKC was similar to ameloblastoma ,and ameloblastoma presented higher values than OKC (p=0.000). Conclusion: The results of this study show 1) Though OKC and DC are developmental in origin and radicular cyst is inflammatory, OKC has intrinsic growth potential among these cyst 2). Ameloblastoma has similar proliferative potential as OKC and hence it has been reinforced as KCOT(Keratocystic odontogenic tumour) in the recent classification.

Introduction A putative role for progesterone in the growth of meningioma has been suggested. The aim of this study was to attest the role of progesterone receptor (PR) in predicting the biological behavior of meningioma. Material and methods The study included 30 cases of meningioma, 15 (50%) recurrent and 15 (50%) non-recurrent. The immunohistochemical expression of PR was studied. Cell kinetic using the Ki67/MIB-1 labelling index (LI) was evaluated and correlated to PR expression. Results PR expression was significantly more common in benign meningioma (BM) than atypical meningioma (AM) and malignant meningioma (MM). The mean Ki-67/MIB-1 LI was significantly highest in MM, high in AM and lowest in BM. In PR-negative meningioma, the mean Ki-67/MIB-1 LI was significantly higher compared with PR-positive meningioma. In the recurrent group, PR was frequently immunonegative and the mean Ki-67/MIB-1 LI was higher than that in the non-recurrent group. The difference in PR expression between non-recurrent and recurrent cases was significant only in BM. The difference in Ki-67/ MIB-1 LI was significant only when recurrent meningioma was compared with non-recurrent tumor, irrespective of the grade. Conclusion BM expresses PR more than AM and MM. The absence of this expression in BM implies a likely risk for recurrence. Ki-67/MIB-1 LI is valuable to predict tumor grade and the overall risk of recurrence. However, it must be interpreted with caution in BM.

This paper considers the comparison of experimental spatial and temporal data of mitotic rates measured during corneal epithelial wound healing (CEWH) of a rat model with the predictions of a computer modelling framework. We begin by briefly showing that previous models, used in the study of corneal epithelial wound healing speeds, are inadequate for the study of cell kinetics. We proceed to formulate a new modelling framework more suited to such a study. This framework is simulated in its simplest form, and the results from this motivate a new realisation of the modelling framework, including a caricature of age structuring. Finally, a model with a simple representation of juxtacrine signalling is considered. The final model captures many, though not all, of the trends of the experimental data. This paper thus lays a foundation for the modelling of the cell kinetics of corneal epithelial wound healing, and yields valuable insight regarding the important mechanisms a model should consider in order to reproduce the observed experimental trends.

Activation of inflammatory pathways represents a central mechanism in multiple disease states both acute and chronic. Triggered via either pathogen or tissue damage-associated molecular motifs, common biochemical pathways lead to conserved yet variable physiological and immunological alterations. Dissection and delineation of the determinants and mechanisms underlying phenotypic variance in response is expected to yield novel therapeutic advances. Intravenous (IV) administration of endotoxin (gram-negative bacterial lipopolysaccharide), a specific Toll-like receptor 4 agonist, represents an in vivo model of systemic inflammation in man. National Institutes for Health Clinical Center Reference Endotoxin (CCRE, Escherichia coli O:113:H10:K negative) is employed to reliably and reproducibly generate vascular, hematological, endocrine, immunological and organ-specific functional effects that parallel, to varying degrees, those seen in the early stages of pathological states. Alteration of dose (0.06 - 4 ng/kg) and time-scale of exposure (bolus vs. infusion) allows replication of either acute or chronic inflammation and a range of severity to be elicited, with higher doses (2 - 4 ng/kg) frequently being used to create a 'sepsis-like' state. Established and novel medicinal compounds may additionally be administered prior to or post endotoxin exposure to appreciate their effect on the inflammatory cascade. Despite limitations in scope and generalizability, human IV endotoxin challenge offers a unique platform to gain mechanistic insights into inducible physiological responses and inflammatory pathways. Rationally employed it may aid translation of this knowledge into therapeutic innovations.

Central venous access is often used during apheresis procedure in stem cell collection. The aim of the present study was to evaluate whether central or peripheral venous access has an effect on stem cell yield and the kinetics of the procedure and the product in patients undergoing ASCT after high dose therapy. A total of 327 patients were retrospectively reviewed. The use of peripheral venous access for stem cell yield was significantly more frequent in males compared to females (p = 0.005). Total volume of the product was significantly lower in central venous access group (p = 0.046). As being a less invasive procedure, peripheral venous access can be used for stem cell yield in eligible selected patients. © 2016 Elsevier Ltd.

Space radiation poses significant challenges to space travel, and it is essential to understand the possible adverse effects from space radiation exposure to the radiosensitive organ systems that are important for immediate survival of human, e.g., the hematopoietic system. In this presentation a biomathematical model of granulocytopoiesis is described and used to analyze the blood granulocyte changes seen in the blood of mammalians under continuous and acute radiation exposure. This is one of a set of hematopoietic models that have been successfully utilized to simulate and interpret the experimental data of acute and chronic radiation on rodents. We discuss the underlying implicit regulation mechanism and the biological relevance of the kinetic parameters estimation method. Extension of the model to predictions in dogs and humans systems indicates that the modeling results are consistent with the cumulative experimental and empirical data from various sources. This implies the potential to integrate the models into one united system for monitoring the hematopoietic response of various species under irradiation. Based on the evidence of threshold responses of dogs to extended periods of low daily dose exposures, we discuss the potential health risks of the space traveler under chronic stress of low-dose irradiation and the possibly encountered Solar Particle Events.

Significant advancements in the care of patients with chronic lymphocytic leukemia (CLL) have occurred over the past decade. Nonetheless, CLL remains incurable outside of allogeneic transplantation. CLL is the most common leukemia in the United States and Europe, and new treatments and therapeutic strategies are clearly needed. To address this need, the pathogenesis of CLL has been an area of intense ongoing investigation. These international efforts illuminate a complex biology that is reliant on the interplay of inherited, environmental, and host factors. This broad review will discuss the recent advances in our understanding of CLL biology including the elucidation of inherited and acquired genetic changes; the role of the B-cell receptor and B-cell receptor signaling; CLL cell kinetics; and the interactions in the microenvironment between CLL cells, other immune cells, and stromal elements. This improved understanding of disease pathogenesis is facilitating the development of novel therapeutic treatment strategies.

After accidental radiation exposure, one of the most significant health impairments is the partial or complete failure of the blood forming systems. Depending on the degree of damage, a suitable therapy must be prepared in time. This requires the assessment of the degree of damage of the blood-forming system and, in particular, of the stem-cell pool. A new approach for assessing the degree of hematopoietic impairment based on dynamic reactions of blood counts immediately following radiation exposure is presented. Cell kinetic mathematical models of blood cell turnover, neural networks, and expert-assessed clinical data records of historical radiation accidents are combined to provide a method for automatic classification of patients and to assign them to clinically related categories of severity. Using this computer-assisted approach, it is possible to distinguish those patients that are likely to restore their blood-cell formation autochthonously from those that need stem-cell transplantation.

We introduce a methodology based on the Luria–Delbrück fluctuation model for estimating the cell kinetics of clonally expanding populations. In particular, this approach allows estimation of the net cell proliferation rate, the extinction coefficient and the initial (viable) population size. We present a systematic approach based on spatial partitioning, which captures the local fluctuations of the number and sizes of individual clones. However, partitioning introduces measurement error by inflating the number of clones, which is dependent on time and the degree of cell migration. We perform variousin silicoexperiments to explore the properties of the estimators and we show that there exists a direct relationship between precision and observation time. We also explore the trade-off between the measurement error and the estimation accuracy. By exploring different scales of cellular fluctuations, from the entire population down to those of individual clones, we show that this methodology is useful for inferring important parameters in neoplastic progression.

In this short work, by combining the total cell evolution curve and the two-compartment model, the evolution of one of the subpopulations is simulated while the system interacts with a proliferating regulatory factor.

Mathematical models which describe the dynamics of two vital body systems (hematopoiesis and small intestinal epithelium) in mammals exposed to acute and chronic radiation are developed. These models, based on conventional biological theories, are implemented as systems of nonlinear differential equations. Their variables and constant parameters have clear biological meaning, that provides successful identification and verification of the models in hand. It is shown that the predictions of the models qualitatively and quantitatively agree with the respective experimental data for small laboratory animals (mice, rats) exposed to acute/chronic irradiation in wide ranges of doses and dose rates. The explanation of a number of radiobiological effects, including those of the low-level long-term exposures, is proposed proceeding from the modeling results. All this bears witness to the validity of employment of the developed models, after a proper identification, in investigation and prediction of radiation effects on the hematopoietic and small intestinal epithelium systems in various mammalian species, including humans. In particular, the models can be used for estimating effects of irradiation on astronauts in the long-term space missions, such as Lunar colonies and Mars voyages.

By combining the total cell evolution curve and a two-compartment model interacting with dynamic anti-cancer agents, the evolution of subpopulations has been analytically obtained and investigated in this work.

After removing a circular area of the central corneal epithelium of the rat eye, the labelling indices and the mitotic rates were measured at various times after wounding, both in the cornea and in the adjacent conjunctival epithelium. The proliferative response was most marked in the corneal epithelium adjacent to the wound, but there was also a definite response in the epithelium covering the denuded areas, and in the conjunctival epithelium. The study demonstrated that the conjunctival epithelium. The study demonstrated that the conjunctiva itself plays a role in the healing of a central corneal epithelial wound. The similarities in the cellular response may indicate that both epithelia are under the influence of the same growth-suppressing factors (chalones), and must be looked upon as a unit. However, no support was found for the theory that the limbal area serves as a generative organ for the corneal epithelium.