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Imbalance of placental regulatory T cell and Th17 cell population dynamics in the FIV infected pregnant cat

Imbalance of placental regulatory T cell and Th17 cell population dynamics in the FIV infected pregnant cat

We use the FIV-infected cat model to evaluate para- meters of lentivirus-induced placental inflammation. Our previous data suggest a pro-inflammatory placental microenvironment at early pregnancy in the infected cat, based on the ratio of pro- to anti-inflammatory cyto- kines, expression of IL-6 [16], and the likely decreased population of Tregs [17]. In the present study we hypothesized that FIV infection in the pregnant cat causes altered placental Treg and Th17 cell population dynamics, allowing placental inflammation that may compromise pregnancy. Placental immunology is dis- tinctly different at early and late stages of pregnancy; therefore, it was important to evaluate the impact of FIV infection in the feline placenta at these two time points. Our first objective was to localize the two cell popula- tions by labeling parallel sections with either FoxP3 or ROR γ -specific antibody and comparing both to a parallel specimen immunolabeled with anti-relaxin antibody. As relaxin is produced by trophoblasts, its presence demar- cates the maternal-fetal interface. The two cell popula- tions were localized to this region. Our second objective was to quantify the expression of Treg marker FoxP3 and Th17 marker RORγ in placental samples from FIV- infected and control queens at early gestation by im- munofluorescence confocal microscopy. FoxP3 expres- sion was significantly reduced in infected tissues while ROR γ expression was unaffected. FoxP3 and ROR γ were
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Consequences of cell-to-cell P-glycoprotein transfer on acquired multidrug resistance in breast cancer: a cell population dynamics model

Consequences of cell-to-cell P-glycoprotein transfer on acquired multidrug resistance in breast cancer: a cell population dynamics model

Resistance to chemotherapy is related to the overall mechanisms that are involved in a decrease of drug effi- cacy against tumours [9]. Among these factors, proteins lowering the intracellular concentration of chemothera- peutics and belonging to the ATP-binding Cassette (ABC) transporters are well-known for their specific responsibility [10]. These membrane proteins are charac- terized by their ability to efflux a large panel of both che- mically and functionally unrelated compounds comprising potent cytotoxics currently used in chemo- therapeutic treatments. Consequently, tumours overex- pressing this type of energy-dependent pump have been very early identified on the basis of their Multi-Drug Resistance (MDR) phenotype [11]. The P-glycoprotein (P-gp) was the first drug-efflux protein characterized [12]. With the growing number of molecularly cloned ABC transporters (48 different genes up to now have been identified in the human genome), a rational nomen- clature have been proposed. Meta-analysis [13] or immu- nochemistry studies [14] have determined that approximately 40% of all breast cancer tumours express ABCB1/MDR1 coded P-gp. ABCB1/MDR1 gene expres- sion has a prognostic value for cell resistance to antican- cer drugs [15,16] and for treatment failure [17].
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A model of stem cell population dynamics: in silico analysis and in vivo validation

A model of stem cell population dynamics: in silico analysis and in vivo validation

Although this system is relatively simple, many central features remain unresolved or controversial. For example, because the field lacks a cell-specific readout for GLP-1/Notch receptor activity, the precise range of signaling is unknown. The DTC body itself directly contacts germ cells over a distance of ~2-3 cell diameters (CD). However, this cell bears long processes that contact germ cells further from the tip, and the role of these processes in signaling, if any, is unclear. Some processes extend to the proliferation/differentiation border (~20 CD) in the early adult (Fitzgerald and Greenwald, 1995; Henderson et al., 1994), but their average length is shorter [~8-10 CD (Hall et al., 1999)] and does not always correlate with underlying germline differentiation (Crittenden et al., 2006). The field also currently lacks markers to trace lineage and to distinguish putative stem cells from transit- amplifying cells. Finally, long-term imaging in real time is technically challenging. Nevertheless, complex cell behaviors have been tracked by arduous large-scale timecourse analysis of fixed specimens (Cinquin et al., 2010; Crittenden et al., 2006; Hansen et al., 2004a; Jaramillo-Lambert et al., 2007; Maciejowski et al., 2006; Michaelson et al., 2010).
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Asymptotic properties of stochastic population dynamics

Asymptotic properties of stochastic population dynamics

The main aim is to study the asymptotic properties of the solution. It is known (see e.g. [3, 20]) if the noise is too large then the population may become extinct with probability one. Our main aim here is to find out what happens if the noise is relatively small. In this paper we will establish some new asymptotic properties for the moments as well as for the sample paths of the solution. In particular, we will discuss the limit of the average in time of the sample paths.

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The Dynamics of Population and Economic Growth in Nigeria

The Dynamics of Population and Economic Growth in Nigeria

Much of contemporary economics on population problems has centered on what could be the optimum size and its impact on economic growth and development.According to Ali et al., (2013), there are three major views on the issue of the type of relationship between population growth and economic growth. There is thePessimistic view which expected a ''population bomb '' as a result of population growth. This implies that as the food supplies growing arithmetically and population is growing geometrically a point would be reached when there would be no more food to feed the growing population and humans will start to feed on their deads.The second view is the Optimistic theory which was of the opinion that population is important for economic growth because it enhances the productive capacity of the economy as population growth leads to increase in labour supply thereby reducing labour cost. This is believed to be able to give firms and employers of labour a better opportunity of hiring more labour into the production process and thereby leading to a reduction in the unemployment rate and increase in the general output of the concerned economy.The third view is that of the Neutralistswho believe that population does not have anything to do with economic development.However, there is no universal consensus as to whether population expansion is beneficial, detrimental or neutral to economic growth.
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POPULATION DYNAMICS AND WOMEN'S HEALTH IN INDIA

POPULATION DYNAMICS AND WOMEN'S HEALTH IN INDIA

Women are the half sky of the human universe. It is told that while creating women the Almighty Creator was so kind that He mixed various elements like the gentleness of a lamb, softness of the bubbles of sea water, color of vibjure, fragrance of rose into one admixture and created women. The position and status of women are always the subject matter of discussion, criticism or research since time immemorial. The status of women differs from time to time, community to community, family to family, caste to caste as well. Like all the major religions of the world, Hinduism is a predominantly male dominated religion where women play a secondary role. Women are protected father in childhood, by husband in youth, and by sons in old age. The current article highlights the population dynamics and women's health in India.
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Population dynamics in Gambia: an ARIMA approach

Population dynamics in Gambia: an ARIMA approach

Employing annual time series data on total population in Gambia from 1960 to 2017, I model and forecast total population over the next 3 decades using the Box – Jenkins ARIMA technique. Diagnostic tests such as the ADF tests show that Gambia annual total population is I (2). Based on the AIC, the study presents the ARIMA (3, 2, 1) model and our diagnostic tests also indicate that the presented model is stable. The results of the study reveal that total population in Gambia will continue to gradually rise in the next three decades. In order to take advantage of the expected increase in total population in Gambia, 4 policy recommendations have been proposed for consideration by the Gambian policy makers.
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A modified model of the population dynamics of mosquitoes

A modified model of the population dynamics of mosquitoes

Simulated population for Macdonald's Model, expected life ez and presumptive mortality qz versus the number of ovipositions... NUMBER OF OVIPOSITIONS..[r]

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Population dynamics and stochastic particle systems

Population dynamics and stochastic particle systems

tion 2.12 below). The system phase separates into a condensate and a homogeneous background. The homogeneous background is distributed according to the maximal invariant measure with critical density and the excess mass concentrates on a subex- tensive part of the lattice, establishing the condensed phase. In finite systems with stationary product measures, the condensed phase occupies only a single lattice site, which is located uniformly at random on the lattice. Condensing models with ho- mogeneous stationary product measures have attracted significant research interest (see e.g. [24, 35] for recent summaries), including zero-range processes of the type introduced in [29, 33], inclusion processes with a rescaled system parameter [54, 18] and explosive condensation models [95, 21]. The role of spatial inhomogeneities and their interplay with particle interactions is summarised in detail for zero-range pro- cesses in [49] (see also [24] and [78] for further references), and in this thesis we only focus on spatially homogeneous processes. While the stationary measures have been understood in great detail on a rigorous level [62, 55, 6, 4, 24], the dynamics of these processes continues to pose interesting mathematical questions. First recent results for zero-range and inclusion processes have been obtained on metastability in the stationary dynamics of the condensate location [11, 5, 15], approach to stationar- ity on fixed lattices under diverging particle density [54, 10], a hydrodynamic limit for density profiles below the critical value [91], and also in the context of related population models [28].
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Multiple Endemic Solutions in an Epidemic Hepatitis B Model without Vertical Transmission

Multiple Endemic Solutions in an Epidemic Hepatitis B Model without Vertical Transmission

The projected model represents the situation when the population dynamics are at their equilibrium. This state can be achieved by transforming the state variables into proportions, i.e., modify system (1.4) into a model of proportions. This transformation eliminates the vital dynamics (birth and death) from the model and hence the reason why we refer to the resultant model as the projected model.

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Population specific social dynamics in chimpanzees

Population specific social dynamics in chimpanzees

population-level variation in sociality across four neighboring populations of chimpanzees... Using standardized methodology, we report substantial differences in social affiliation and.[r]

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Modeling the population dynamics of lemon sharks

Modeling the population dynamics of lemon sharks

the box for “Sampling Length” 400 (the right-most box in the figure). To construct that box, we start with a single simulation of length 500 time points. We then threw out the first 100 time points and calculated the variance of the remaining 400. We repeated this procedure 99 times to obtain 100 variances. The box plot shows the distribu- tion of these 100 variances (median variance with quartiles and outliers greater than 1.5 times the inner quartile range from the edge of the box). We recognize that we did not make our main argument clear enough. So, because Figure 5 is central to our argument, we reiterate our think- ing here and have tried to clarify it in the main text as well. What we see in Figure 5 is an increase in the median of the variances as the length of the “study” increases. However, this median, indeed the inner quartile range, never reaches the observed variance even for samples of 400 years. For samples of 20 years, nearly the length of the field study, not one of the 100 simulations–not even an outlier–generated a variance equal to or greater than our observed variance (although 2 of 100 did for 10 year samples–see Figure 5). If we lump the two sampling dis- tributions of the variance for sample sizes nearest ours (10 and 20), then the observed variance was exceeded in only 2 of 200 simulation runs, suggesting a p-value no larger than 0.01. So, the demographic model can gener- ate, on occasion, variances that approach or exceed what we observe in the field, but only with a reasonable prob- ability for studies of at least 100 years, and even in the best case (a 400 year study) it would be never more than 25% or so (being conservative). Therefore, the variance from our sample of 17 years is unlikely to have been gen- erated by demographic stochasticity. It is also unlikely to have been generated by complex dynamics (which would also have been captured in the model and is anyway unlikely with such limited density-dependence). It is also unlikely to be generated by the assumption of equal sex ratios (see response to Dr. Hyrien’s comments). Therefore, we are left with a diagnosis by exclusion—the most likely candidate, in our opinion, for the higher than predicted variance is environmental stochasticity. This conclusion is further supported by the apparent outliers in 2005 and 2008.
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Calculation of disease dynamics in a population of households

Calculation of disease dynamics in a population of households

Early mathematical representations of infectious disease dynamics assumed a single, large, homogeneously mixing population. Over the past decade there has been growing interest in models consisting of multiple smaller subpopulations (households, workplaces, schools, communities), with the natural assumption of strong homogeneous mixing within each subpopulation, and weaker transmission between subpopulations. Here we consider a model of SIRS (susceptible- infectious-recovered-susceptible) infection dynamics in a very large (assumed infinite) population of households, with the simplifying assumption that each household is of the same size (although all methods may be extended to a population with a heterogeneous distribution of household sizes). For this households model we present efficient methods for studying several quantities of epidemiological interest: (i) the threshold for invasion; (ii) the early growth rate; (iii) the household offspring distribution; (iv) the endemic prevalence of infection; and (v) the transient dynamics of the process. We utilize these methods to explore a wide region of parameter space appropriate for human infectious diseases. We then extend these results to consider the effects of more realistic gamma-distributed infectious periods. We discuss how all these results differ from standard homogeneous-mixing models and assess the implications for the invasion, transmission and persistence of infection. The computational efficiency of the methodology presented here will hopefully aid in the parameterisation of structured models and in the evaluation of appropriate responses for future disease outbreaks.
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Pharmacological Evaluation for the Antifertility Effect of the Ethanolic Seed Extract of Nelumbo Nucifera (Sacred Lotus)

Pharmacological Evaluation for the Antifertility Effect of the Ethanolic Seed Extract of Nelumbo Nucifera (Sacred Lotus)

12. Liu, C.P., Tsai, W.J., Lin, Y.L., Liao, J.F., Chen, C.F., Kuo, Y.C. The extracts from Nelumbo nucifera suppress cell cycle progression, cytokine genes expression and cell proliferation in human peripheral blood mononuclear cells. Life Sci 2004; 75: 699-716. 13. Chopra, R.N., Nayar, S.L., Chopra, I.C.

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Regulation of cell migration by dynamic microtubules

Regulation of cell migration by dynamic microtubules

It is likely that all these functions of microtubule-associated proteins relate to their function in regulating microtubule dynamics. All MAPs implicated in cell migration thus far stabilise microtubules: EB1 and APC have been shown to act downstream of Rho and mDia in the stabilisation of microtubules to the front of migrating cells [74], EB1 and EB3 promote persistent microtubule growth in the cytoplasm [75], and APC stabilises microtubules by promoting growth, slowing shrinkage and decreasing transition frequencies [76]. MAP1b stabilizes microtubules and serves as a major scaffolding factor for microtubule-related activities in neurons [77, 78]. RASSF1a acts as a microtubule lattice-associated MAP acting in conjunction with small GTPase RAN to cause microtubule over-stabilization [79]. CLIP-170 and CLASPs possess rescue factor activity [80-82] that increases the cortical dwell time of microtubules [13]. A loss of stable (cold or drug-resistant) microtubules is frequently observed when these microtubule stabilisers are deleted from cells [70, 74, 77]. Although each of these proteins enhances microtubule stability by a specific mechanism, it is plausible to suggest that
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Seasonal population dynamics of cocoa stem borer Eulophonotusmyrmeleon felder (Lepidoptera: Cossidae) in the region of the Indénié Djuablin in Côte D'ivoire

Seasonal population dynamics of cocoa stem borer Eulophonotusmyrmeleon felder (Lepidoptera: Cossidae) in the region of the Indénié Djuablin in Côte D'ivoire

The results of the observation son damages caused by the cocoa stem borer Eulophonotusmyrmeleon in the region of the Indénié-Djuablin indicated significant changes in population densities of larvae and the rate of attacks of this pest. These variations could be explained by the fact that certain environments are more favourable to the development of these insects (Leroux et al., 2013). According to these authors, most insects, due to their high mobility, can conquer other environments that are favourable as existing not ecological or physical barriers. Also, our results show that the population density of larvae and the rate of attacks have also varied from one year to the other. N'Guessan (2007) indicated that in Côte d'Ivoire, attacks that had started in the eastern region of the country, quickly progressed to the West. This could explain the level of population and the rate of attacks higher in 2009 than in other years. Indeed, in recent years, the cocoa loop located to the East of the country, knows a reverse situation following deterioration in the conditions that prevailed over the introduction of coffee and cocoa (Aloko-N'Guessan et al., 2014). Degradation of the cocoa farms in this region would result in the migration of pests to most environments, these last years. In this region, two periods of heavy attacks were observed during the year. These results are consistent with those obtained by N'Guessan et al. (2010) and N'Guessan et al. (2014), which had identified also two periods of this pest outbreaks respectively the areas of Sud-Bandama and Haut- Sassandra in Côte d'Ivoire. However, these periods of overgrowth not overlap from one region to the other. In effect, N'Guessan et al. (2010) showed that in the region of Sud- Bandama, periods of heavy attacks extend from May to August and from November to February. Then N'Guessan et al. (2014) indicated that in the region of Haut-Sassandra, periods of heavy attacks extend from January to April with a peak February and from June to October with a peak in August.
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Correlation of population pharmacokinetics and dynamics of commonly used aminoglycoside amikacin with snp’s (single neucleotide polymorphism)

Correlation of population pharmacokinetics and dynamics of commonly used aminoglycoside amikacin with snp’s (single neucleotide polymorphism)

is an antibiotic used . This includes intra urinary tract infections. It multidrug-resistant injection into a vein or muscle. Amikacin have the potential to produce reversible and irreversible vestibular, cochlear, and renal toxicity. These side effects complicate the use of these compounds and make their Bliziotis et al., 2005) Population pharmacokinetics in the drug development process to help identify differences in drug safety and efficacy among population subgroups. It summarizes scientific and regulatory issues that should be addressed using population tics. The guidance discusses when to perform a population pharmacokinetic study and/or analysis; how to
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Live Cell Imaging of Phosphoinositide Dynamics and Membrane Architecture during Legionella Infection

Live Cell Imaging of Phosphoinositide Dynamics and Membrane Architecture during Legionella Infection

PtdIns(4)P stably accumulated on LCVs harboring wild-type L. pneumophila during 2 h and up to 8 h after infection (Fig. 5 and 6). The PI was not cleared later but continued to tightly and in- tensely label the LCV after multiple rounds of replication at 18 h p.i. and likely persisted until bacterial exit from infected cells (see Fig. S2 in the supplemental material). PtdIns(4)P serves as an anchor for several secreted L. pneumophila effectors. The ER in- teractor SidC and the Rab1 GEF/AMPylase SidM specifically bind to PtdIns(4)P (35, 37). The stable accumulation of PtdIns(4)P on LCV membranes is in agreement with the finding that L. pneumo- phila effectors bind to this PI lipid throughout the course of infec- tion. SidM was detected on LCV membranes up to 4 h p.i. (60), and SidC was routinely detected at 1 to 2 h p.i. but is likely present on LCVs also much beyond this time point. This notion is sup- ported by the fact that intact LCVs can be purified by immunoaf- finity separation using an anti-SidC antibody at 6 h and even at 14 h p.i. with the same efficiency as that at earlier time points (61). The kinetics of PtdIns(4)P acquisition (Fig. 5D) and calnexin recruitment (36) are similar, yielding within 1 h and 2 h p.i. ap- FIG 7 Schematic of PI dynamics during L. pneumophila infection in D. discoideum. L. pneumophila enters D. discoideum upon formation of a phagocytic cup rich in PtdIns(3,4,5)P 3 and PtdIns(4)P. The phagosome fuses and is internalized, where PtdIns(3,4,5)P 3 and PtdIns(3,4)P 2 , along with PtdIns(4)P, persist for less
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POPULATION DYNAMICS OF A. (DC) IN AN Castanopsis tribuloides UNDISTURBED AND DISTURBED TROPICAL FOREST STANDS OF NORTH- EAST INDIA

POPULATION DYNAMICS OF A. (DC) IN AN Castanopsis tribuloides UNDISTURBED AND DISTURBED TROPICAL FOREST STANDS OF NORTH- EAST INDIA

Tropical semi evergreen forests of Mizoram, in northeast India are being modified and degraded due to increased anthropogenic pressure. Castanopsis tribuloides A. (DC) is one of the dominating tree species in this forest type of Mizoram (Lalfakawma et al., 2009), however, its populations are now under threats due to large scale deforestation of their suitable habitats and unsustainable extraction for fuel wood by the local people. The timber of this species being hard and durable is popular for construction posts and beams as well as fence posts; besides high calorific value properties of the wood (Rai et al., 2002) makes it a preferred fuel wood species among the local people and the fruits too are popular nuts consumed and sold in the market (Lalfakawma et al., 2009). The species maintain and expand its population in time and space by the process of regeneration, which in turn is determined by successful completion of several events such as seed production, dispersal to safe sites, germination and seedling emergence, establishment and onward growth in the tree life cycle (Barik et al., 1996a). Furthermore the successful regeneration of tree is also determined by the presence of sufficient number of seedlings, saplings and young trees in a given population (Saxena & Singh, 1984). Regeneration of tree species, survival and growth of their seedlings depend upon the interactive influence of biotic and abiotic factors of the forest environment. Available microsites created by local disturbances are arenas where seeds may germinate and established without significant competitive effect from other plants (Grubb, 1977; Coffin & Lauenroth, 1988; Huston, 1994; Chambers, 1995). Therefore, the presence or absence of disturbances alters local immigration and extinction processes (Glen & Collins, 1992). Seedling establishment, which is an important determinant of plant community species richness (Tilman, 1993; Weiher & Keddy, 1995), is limited by both abiotic stress and biotic interactions, but the relative significance of these two groups of factors changes along the productivity gradient (Zobel et al., 2000).
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Evolution of cancer cell populations under cytotoxic therapy and treatment optimisation : insight from a phenotype structured model

Evolution of cancer cell populations under cytotoxic therapy and treatment optimisation : insight from a phenotype structured model

In current clinical practice, it is common to give the MTD of cytotoxic agents at the beginning of a therapy cycle and then let the patient recover from toxicities. In the last decade, experimental and theoretical efforts have been made to determine the best scheduling of cytotoxic agents in anticancer therapy; unfortunately, there is still no clear answer about optimal administration protocols [58]. Our theoretical work demonstrates that higher doses of cytotoxic drugs reduce the size of cancer cell populations at the cost of promoting the selection for more resistant phenotypic variants. Moreover, our results provide a conceptual basis for the benefits of metronomic therapy [2, 4, 26, 32, 45, 59] – which relies on continuous treatment with lower doses of cytotoxic agents – as it performs more closely to the optimal dosing regimen in the case where the goal is to minimise the average number of viable cancer cells during the course of treatment. The parameter values that we have used to carry out numerical simulations are derived from leukemia datasets. However, given the robustness and structural stability of our results, we expect these conclusions to hold for different types of cancer.
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