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5,700 | Control of spiral waves and turbulent states in a cardiac model by travelling-wave perturbations | q-bio.TO | We propose a travelling-wave perturbation method to control the
spatiotemporal dynamics in a cardiac model. It is numerically demonstrated that
the method can successfully suppress the wave instability (alternans in action
potential duration) in the one-dimensional case and convert spiral waves and
turbulent states to ... | biology |
5,701 | To a Problem of Not Increasing Dynamic Compliance at Asthma Patients with Ventilating Disorders after Berotec Inhalation | q-bio.TO | The purpose of research was to check up the influence of decrease of
nonequality of ventilating (after bronchodilator (berotec) inhalation (BI)) on
the magnitude of dynamic compliance of lungs (Cdyn) at asthma patients with
ventilating infringements. Methods and materials: 20 patients (with 2 and 3
degrees of ventilati... | biology |
5,702 | Dynamics of Acute Inflammation | q-bio.TO | When the body is infected, it mounts an acute inflammatory response to rid
itself of the pathogens and restore health. Uncontrolled acute inflammation due
to infection is defined clinically as Sepsis and can culminate in organ failure
and death. We consider a three dimensional ordinary differential equation model
of in... | biology |
5,703 | On tumor development: fractional transport approach | q-bio.TO | A growth of malignant neoplasm is considered as a fractional transport
approach. We suggested that the main process of the tumor development through a
lymphatic net is fractional transport of cells. In the framework of this
fractional kinetics we were able to show that the mean size of main growth is
due to subdiffusio... | biology |
5,704 | Periodic Oscillations of Blood Cell Populations in Chronic Myelogenous Leukemia | q-bio.TO | We develop some techniques to prove analytically the existence and stability
of long period oscillations of stem cell populations in the case of periodic
chronic myelogenous leukemia. Such a periodic oscillation $p_\infty $ can be
analytically constructed when the hill coefficient involved in the nonlinear
feedback is ... | biology |
5,705 | Oscillations in a maturation model of blood cell production | q-bio.TO | In this paper we use a continuous model to describe the development of a
single cell lineage following the committal of stem cells. Three separate
controls are implemented in the model, namely the proliferative control of stem
cells, the proliferative control of developing blast cells, and the peripheral
control of ste... | biology |
5,706 | Critical Scale-invariance in Healthy Human Heart Rate | q-bio.TO | We demonstrate the robust scale-invariance in the probability density
function (PDF) of detrended healthy human heart rate increments, which is
preserved not only in a quiescent condition, but also in a dynamic state where
the mean level of heart rate is dramatically changing. This scale-independent
and fractal structu... | biology |
5,707 | In vivo Cancer Marker in Mice | q-bio.TO | This work introduces an in vivo marker in mice from the altitude of the well,
determined by this cancer.The duration of development and the altitude of the
cancer well are obtained from the synchronization of the mechanics and the
kinetics of the processes of normal and anomalous transport under tumor mass
growth.The m... | biology |
5,708 | Energetic model of tumor growth | q-bio.TO | A macroscopic model of the tumor Gompertzian growth is proposed. This
approach is based on the energetic balance among the different cell activities,
described by methods of statistical mechanics and related to the growth
inhibitor factors. The model is successfully applied to the multicellular tumor
spheroid data. | biology |
5,709 | Telomere loss limits the rate of human epithelial tumor formation | q-bio.TO | Most human carcinomas exhibit telomere abnormalities early in the
carcinogenesis process suggesting that crisis caused by telomere shortening may
be a necessary event leading to human carcinomas. Epidemiological records of
the age at which each patient in a population develops carcinoma are known as
age-incidence data;... | biology |
5,710 | Modelling butterfly wing eyespot patterns | q-bio.TO | Eyespots are concentric motifs with contrasting colours on butterfly wings.
Eyespots have intra- and inter-specific visual signalling functions with
adaptive and selective roles. We propose a reaction-diffusion model that
accounts for eyespot development. The model considers two diffusive morphogens
and three non-diffu... | biology |
5,711 | Comments on "Structural dynamics and resonance in plants with nonlinear stiffness" | q-bio.TO | We make comments on the paper by Miller [{\it J. Theor. Biol.} {\bf 234}
(2005) 511]. | biology |
5,712 | Studies on European beech (Fagus sylvatica L.). Part 1: Variations of wood colour parameters | q-bio.TO | Colour parameters of European beech were measured using CIELab system. 103
logs from 87 trees in 9 sites were cut into boards to study the variations of
wood colour parameters. Both site and tree effect on colour were observed.
Patterns of red heartwood occurrence were defined. When excepting red heartwood
there was st... | biology |
5,713 | Biological remodelling: Stationary energy, configurational change, internal variables and dissipation | q-bio.TO | Remodelling is defined as an evolution of microstructure or variations in the
configuration of the underlying manifold. The manner in which a biological
tissue and its subsystems remodel their structure is treated in a continuum
mechanical setting. While some examples of remodelling are conveniently
modelled as evoluti... | biology |
5,714 | Signal analysis of impulse response functions in MR- and CT-measurements of cerebral blood flow | q-bio.TO | The impulse response function (IRF) of a localized bolus in cerebral blood
flow codes important information on the tissue type. It is indirectly
accessible both from MR- and CT-imaging methods, at least in principle. In
practice, however, noise and limited signal resolution render standard
deconvolution techniques almo... | biology |
5,715 | Flow correlated percolation during vascular network formation in tumors | q-bio.TO | A theoretical model based on the molecular interactions between a growing
tumor and a dynamically evolving blood vessel network describes the
transformation of the regular vasculature in normal tissues into a highly
inhomogeneous tumor specific capillary network. The emerging morphology,
characterized by the compartmen... | biology |
5,716 | Long-range dependencies in heart rate signals- revisited | q-bio.TO | The RR series extracted from human electrocardiogram signal (ECG) is
considered as a fractal stochastic process. The manifestation of long-range
dependencies is the presence of power laws in scale dependent process
characteristics. Exponents of these laws: $\beta$ - describing power spectrum
decay, $\alpha$ - responsib... | biology |
5,717 | Does Cancer Growth Depend on Surface Extension? | q-bio.TO | We argue that volumetric growth dynamics of a solid cancer depend on the
tumor system's overall surface extension. While this at first may seem evident,
to our knowledge, so far no theoretical argument has been presented explaining
this relationship explicitly. In here, we therefore develop a conceptual
framework based... | biology |
5,718 | Influence of stochastic delays in Seidel-Herzel model of human cardiorespiratory system | q-bio.TO | Experiments that discuss influence of noise to H. Seidel and H. Herzel
dynamics model of human cardiovascular system are presented. Noise is
introduced by considering stochastic delays in response to the sympathetic
system. It appears that in the presence of the noise 10 s heart rate
oscillations connected with Mayer w... | biology |
5,719 | Tumors under periodic therapy -- Role of the immune response time delay | q-bio.TO | We model the interaction between the immune system and tumor cells including
a time delay to simulate the time needed by the latter to develop a chemical
and cell mediated response to the presence of the tumor. The results are
compared with those of a previous paper, concluding that the delay introduces
new instabiliti... | biology |
5,720 | A continuous model for cell sorting | q-bio.TO | The differential Adhesion Hypothesis (DAH) is a theory of the organization of
cells within a tissue. In this study we introduce a stochastic model supporting
the DAH, that can be seen as a continuous version of a discrete model of Graner
and Glazier. Our approach is based on the mathematical framework of Gibbsian
marke... | biology |
5,721 | Evidence for an unfolded border-collision bifurcation in paced cardiac tissue | q-bio.TO | We investigate, both experimentally and theoretically, the bifurcation to
alternans in heart tissue. Previously, this phenomenon has been modeled either
as a smooth or as border-collision period-doubling bifurcation. Using a new
experimental technique, we find a hybrid behavior: very close to the
bifurcation point the ... | biology |
5,722 | Asymptotic analysis and analytical solutions of a model of cardiac excitation | q-bio.TO | We describe an asymptotic approach to gated ionic models of single-cell
cardiac excitability. It has a form essentially different from the Tikhonov
fast-slow form assumed in standard asymptotic reductions of excitable systems.
This is of interest since the standard approaches have been previously found
inadequate to de... | biology |
5,723 | Cancer Dissemination: A Consequence of limited Carrying Capacity? | q-bio.TO | Assuming that there is feedback between an expanding cancer system and its
organ-typical microenvironment, we argue here that such local tumor growth is
guided by co-existence rather than competition with the surrounding tissue. We
then present a novel concept that understands cancer dissemination as a
biological mecha... | biology |
5,724 | Can all muscular load sharing patterns be regarded as optimal in some sense? | q-bio.TO | Muscles crossing a joint usually outnumber its degrees of freedom, which
renders the motor system underdetermined. Typically, optimization laws are
postulated to cope with this redundancy. A natural question then arises whether
all muscular load sharing patterns can be regarded as results of optimization.
To answer it,... | biology |
5,725 | The micromechanics of fluid-solid interactions during growth in porous soft biological tissue | q-bio.TO | In this paper we address some modelling issues related to biological growth.
Our treatment is based on a recently-proposed, general formulation for growth
within the context of Mixture Theory (Journal of the Mechanics and Physics of
Solids, 52, 2004, 1595--1625). We aim to enhance this treatment by making it
more appro... | biology |
5,726 | Analyzing the Dynamic Relationship between Tumor Growth and Angiogenesis in a Two Dimensional Finite Element Model | q-bio.TO | Employing a novel two-dimensional computational model we have simulated the
feedback between angiogenesis and tumor growth dynamics. Analyzing vessel
formation and elongation towards the concentration gradient of the
tumor-derived angiogenetic basic fibroblast growth factor, bFGF, we assumed
that prior to the blood ves... | biology |
5,727 | Fitting analysis provides further evidence for eradication of hiv/aids infection under combined liposome drug delivery treatment | q-bio.TO | It is now evident that the commonly accepted strategy for treatment of
HIV/AIDS by highly active antiretroviral therapy (HAART) will not lead to
eradication of HIV in a reasonable time. This is straightforward from the
typical exponential viral load decay upon treatment revealing initial
considerable but incomplete red... | biology |
5,728 | Regional distribution of the prostaglandin E2 receptor EP1 in the rat brain: accumulation in Purkinje cells of the cerebellum | q-bio.TO | Prostaglandin E2 (PGE2), is a major prostanoid produced by the activity of
cyclooxygenases (COX) in response to various physiological and pathological
stimuli. PGE2 exerts its effects by activating four specific E-type prostanoid
receptors (EP1, EP2, EP3, and EP4). In the present study, we analyzed the
expression of th... | biology |
5,729 | Delayed treatment with nimesulide reduces measures of oxidative stress following global ischemic brain injury in gerbils | q-bio.TO | Metabolism of arachidonic acid by cyclooxygenase is one of the primary
sources of reactive oxygen species in the ischemic brain. Neuronal
overexpression of cyclooxygenase-2 has recently been shown to contribute to
neurodegeneration following ischemic injury. In the present study, we examined
the possibility that the ne... | biology |
5,730 | Neuroprotective efficacy of nimesulide against hippocampal neuronal damage following transient forebrain ischemia | q-bio.TO | Cyclooxygenase-2 is involved in the inflammatory component of the ischemic
cascade, playing an important role in the delayed progression of the brain
damage. The present study evaluated the pharmacological effects of the
selective cyclooxygenase-2 inhibitor nimesulide on delayed neuronal death of
hippocampal CA1 neuron... | biology |
5,731 | Time course of oxidative damage in different brain regions following transient cerebral ischemia in gerbils | q-bio.TO | The time course of oxidative damage in different brain regions was
investigated in the gerbil model of transient cerebral ischemia. Animals were
subjected to both common carotid arteries occlusion for 5 min. After the end of
ischemia and at different reperfusion times (2, 6, 12, 24, 48, 72, 96 h and 7
days), markers of... | biology |
5,732 | The highly selective cyclooxygenase-2 inhibitor DFU is neuroprotective when given several hours after transient cerebral ischemia in gerbils | q-bio.TO | Several studies suggest that cyclooxygenase-2 contributes to the delayed
progression of ischemic brain damage. In this study we examined whether the
highly selective cyclooxygenase-2 inhibitor DFU reduces neuronal damage when
administered several hours after 5 min of transient forebrain ischemia in
gerbils. The extent ... | biology |
5,733 | Effects of pyruvate administration on infarct volume and neurological deficits following permanent focal cerebral ischemia in rats | q-bio.TO | Recent experimental evidences indicate that pyruvate, the final metabolite of
glycolysis, has a remarkable protective effect against different types of brain
injury. The purpose of this study was to assess the neuroprotective effect and
the neurological outcome after pyruvate administration in a model of ischemic
strok... | biology |
5,734 | Nimesulide limits kainate-induced oxidative damage in the rat hippocampus | q-bio.TO | Kainate induces a marked expression of cyclooxygenase-2 after its systemic
administration. Because cyclooxygenase-2 activity is associated to the
production of reactive oxygen species, we investigated the effects of
nimesulide, a selective cyclooxygenase-2 inhibitor, on kainate-induced in vivo
oxidative damage in the r... | biology |
5,735 | Selective vulnerability to kainate-induced oxidative damage in different rat brain regions | q-bio.TO | Some markers of oxidative injury were measured in different rat brain areas
(hippocampus, cerebral cortex, striatum, hypothalamus, amygdala/piriform cortex
and cerebellum) after the systemic administration of an excitotoxic dose of
kainic acid (KA, 9 mg kg(-1) i.p.) at two different sampling times (24 and 48
h). Kainic... | biology |
5,736 | Modeling the variability of shapes of a human placenta | q-bio.TO | While it is well-understood what a normal human placenta should look like, a
deviation from the norm can take many possible shapes. In this paper we propose
a mechanism for this variability based on the change in the structure of the
vascular tree. | biology |
5,737 | Morphogenesis of growing soft tissues | q-bio.TO | Recently, much attention has been given to a noteworthy property of some soft
tissues: their ability to grow. Many attempts have been made to model this
behaviour in biology, chemistry and physics. Using the theory of finite
elasticity, Rodriguez has postulated a multiplicative decomposition of the
geometric deformatio... | biology |
5,738 | A ptototype compartmental model of blood pressure distribution | q-bio.TO | We consider a system of differential equations the behavior of which
solutions possesses several properties characteristic of the blood pressure
distribution. The system can be used for a compartmental modeling of the
cardiovascular system. It admits a unique bounded solution such that all
coordinates of the solution a... | biology |
5,739 | Hot spot formation in tumor vasculature during tumor growth in an arterio-venous-network environment | q-bio.TO | Hot spots in tumors are regions of high vascular density in the center of the
tumor and their analysis is an important diagnostic tool in cancer treatment.
We present a model for vascular remodeling in tumors predicting that the
formation of hot spots correlates with local inhomogeneities of the original
arterio-venous... | biology |
5,740 | Hepatocyte Aggregates: Methods of Preparation in the Microgravity Simulating Bioreactor Use in Tissue Engineering | q-bio.TO | Tissue Engineering concerns the three-dimensional cell growth so that
bio-artificial tissues could be created and used for transplantation. The
recently expressed concerns from the Tissue Engineering research community for
a re-direction of the research activities necessitate the proposition of new
methodologies. We pr... | biology |
5,741 | The dynamics of human body weight change | q-bio.TO | An imbalance between energy intake and energy expenditure will lead to a
change in body weight (mass) and body composition (fat and lean masses). A
quantitative understanding of the processes involved, which currently remains
lacking, will be useful in determining the etiology and treatment of obesity
and other conditi... | biology |
5,742 | Low energy defibrillation in human cardiac tissue: a simulation study | q-bio.TO | We aim to assess the effectiveness of feedback controlled resonant drift
pacing as a method for low energy defibrillation. Antitachycardia pacing is the
only low energy defibrillation approach to have gained clinical significance,
but it is still suboptimal. Low energy defibrillation would avoid adverse side
effects as... | biology |
5,743 | New Mechanics of Traumatic Brain Injury | q-bio.TO | The prediction and prevention of traumatic brain injury is a very important
aspect of preventive medical science. This paper proposes a new coupled
loading-rate hypothesis for the traumatic brain injury (TBI), which states that
the main cause of the TBI is an external Euclidean jolt, or SE(3)-jolt, an
impulsive loading... | biology |
5,744 | Stroke volume estimation by thoracocardiography is better when glottis is closed | q-bio.TO | Thoracocardiography approach pretends to non-invasively monitor stroke volume
by inductive plethysmographic recording of ventricular volume curves by a
transducer placed on the chest. The purpose of this study was to investigate
the potential of thoracocardiography to estimate stroke volumes while apnea
with open glott... | biology |
5,745 | SAPHIR - a multi-scale, multi-resolution modeling environment targeting blood pressure regulation and fluid homeostasis | q-bio.TO | We present progress on a comprehensive, modular, interactive modeling
environment centered on overall regulation of blood pressure and body fluid
homeostasis. We call the project SAPHIR, for "a Systems Approach for
PHysiological Integration of Renal, cardiac, and respiratory functions". The
project uses state-of-the-ar... | biology |
5,746 | Potential Phytoextraction with in-vitro regenerated plantlets of Brassica juncea (L.) Czern. in presence of CdCl$_2$: Cadmium accumulation and physiological parameter measurement | q-bio.TO | Heavy metal contamination of agricultural land is partly responsible for
limiting crop productivity. Cd$^{2+}$ is known as a non-essentiel HM that can
be harmful to plants even at low concentrations. Brassica juncea (L.) is able
to accumulate more than 400 $\mu$g.g$^{-1}$ D.W. in the shoot, a physiological
trait which ... | biology |
5,747 | Micropropagation of three genotypes of Indian mustard [{Brassica juncea} (L.) Czern.] using seedling-derived transverse thin cell layer (tTCL) explants | q-bio.TO | Micropropagation of three genotypes of Indian mustard [\textit{Brassica
juncea} (L.) Czern.] using 7-days old seedling-derived transverse thin cell
layer (tTCL) explants was accomplished.
The genotype, explant source and addition of silver nitrate to the medium
significantly influenced shoot bud induction. MS medium ... | biology |
5,748 | Beneficial effects of intercellular interactions between pancreatic islet cells in blood glucose regulation | q-bio.TO | Glucose homeostasis is controlled by the islets of Langerhans which are
equipped with alpha-cells increasing the blood glucose level, beta-cells
decreasing it, and delta-cells the precise role of which still needs
identifying. Although intercellular communications between these endocrine
cells have recently been observ... | biology |
5,749 | Steric Constraints as a Global Regulation of Growing Leaf Shape | q-bio.TO | Shape is one of the important characteristics for the structures observed in
living organisms. Whereas biologists have proposed models where the shape is
controlled on a molecular level [1], physicists, following Turing [2] and
d'Arcy Thomson [3], have developed theories where patterns arise spontaneously
[4]. Here, we... | biology |
5,750 | Aging as a consequence of misrepair -- a novel theory of aging | q-bio.TO | It is now increasingly realized that the underlying mechanism which governs
aging (ageing) is a complex interplay of genetic regulation and
damage-accumulation. "Aging as a result of accumulation of 'faults' on cellular
and molecular levels", has been proposed in the damage (fault)-accumulation
theory. However, this th... | biology |
5,751 | Isoprenaline increases Excursive Restitution Slope in the Conscious Rabbit with Ischaemic Heart Failure | q-bio.TO | Background: An increased QT/RR slope is hypothesized to be predictive of
sudden cardiac death after myocardial infarction. Previous studies have shown
that beta-adrenergic stimulation increases QT/RR slope, but the effects of
beta-adrenergic stimulation on QT/RR slope in heart failure are unknown.
Methods: New Zealand ... | biology |
5,752 | Asymptotics of conduction velocity restitution in models of electrical excitation in the heart | q-bio.TO | We extend a non-Tikhonov asymptotic embedding, proposed earlier, for
calculation of conduction velocity restitution curves in ionic models of
cardiac excitability. Conduction velocity restitution is the simplest
nontrivial spatially extended problem in excitable media, and in the case of
cardiac tissue it is an importa... | biology |
5,753 | Variant assumptions made in deriving equilibrium solutions to Little et al (PLoS Comput Biol 2009 5(10) e1000539) | q-bio.TO | The paper of Little et al. (PloS Comput Biol 2009 5(10) e1000539) outlined a
system of reaction-diffusion equations that were used to describe induction of
atherosclerotic disease. These were solved by considering an equilibrium
solution and small perturbations around this equilibrium. Here we consider
slight variant s... | biology |
5,754 | Growth-Algorithm Model of Leaf Shape | q-bio.TO | The innumerable shapes of plant leaves present a challenge to the explanatory
power of biophysical theory. A model is needed that can produce these shapes
with a small set of parameters. This paper presents a simple model of leaf
shape based on a growth algorithm, which governs the growth rate of leaf tissue
in two dim... | biology |
5,755 | Frequency Structure of Heart Rate Variability | q-bio.TO | Factor structure of heart rate periodogram has been detected with factor
analysis. The results showed that there are at least four periodical phenomena
of HRV. Two of them have not been discovered and physiologically explained yet.
Their frequency ranges are 0.21 to 0.31 1/beat with the peak at 0.26 1/beat and
0.25 to ... | biology |
5,756 | Myocardial Contractions and the Ventricular Pressure--Volume Relationship | q-bio.TO | We present a reduced-order heart model with the aim of introducing a novel
point of view in the interpretation of the pressure-volume loops. The novelty
of the approach is based on the definition of active contraction as opposed to
that of active stress. The consequences of the assumption are discussed with
reference t... | biology |
5,757 | General analysis of mathematical models for bone remodeling | q-bio.TO | Bone remodeling is regulated by pathways controlling the interplay of
osteoblasts and osteoclasts. In this work, we apply the method of generalized
modelling to systematically analyse a large class of models of bone remodeling.
Our analysis shows that osteoblast precursors can play an important role in the
regulation o... | biology |
5,758 | Computational challenges of tumor spheroid modeling | q-bio.TO | The speed and the versatility of today's computers open up new opportunities
to simulate complex biological systems. Here we review a computational approach
recently proposed by us to model large tumor cell populations and spheroids,
and we put forward general considerations that apply to any fine-grained
numerical mod... | biology |
5,759 | Abnormality of the placental vasculature affects placental thickness | q-bio.TO | Our empirical modeling suggests that deformation of placental vascular growth
is associated with abnormal placental chorionic surface shape. Altered
chorionic surface shape is associated with lowered placental functional
efficiency. We hypothesize that placentas with deformed chorionic surface
vascular trees and reduce... | biology |
5,760 | A validated model of serum anti-Mullerian hormone from conception to menopause | q-bio.TO | Background: Anti-Mullerian hormone (AMH) is a product of growing ovarian
follicles. The concentration of AMH in blood may also reflect the non-growing
follicle (NGF) population, i.e. the ovarian reserve, and be of value in
predicting reproductive lifespan. A full description of AMH production up to
the menopause has no... | biology |
5,761 | Human ovarian reserve from conception to the menopause | q-bio.TO | The human ovary contains a fixed number of non-growing follicles (NGFs)
established before birth that decline with increasing age culminating in the
menopause at 50-51 years. The objective of this study is to model the
age-related population of NGFs in the human ovary from conception to menopause.
Data were taken from ... | biology |
5,762 | Psoriasis as a consequence of incorporation of beta-streptococci into the microbiocenosis of highly permeable intestines (a pathogenic concept) | q-bio.TO | A review of recent investigations into pathogenesis of psoriasis summarizing
data on the relationship between the presence {\beta}-streptococci in the
organism and the cutaneous immune reaction. Results of the studies on
gastrointestinal pathology in psoriatic patients are presented. The authors
propose a hypothesis th... | biology |
5,763 | Stability of nonconstant stationary solutions in a reaction-diffusion equation coupled to the system of ordinary differential equations | q-bio.TO | In this paper we study pattern formation arising in a system of a single
reaction-diffusion equation coupled with subsystem of ordinary differential
equations, describing spatially-distributed growth of clonal populations of
precancerous cells, whose proliferation is controled by growth factors
diffusing in the extrace... | biology |
5,764 | Psoriasis as a consequence of incorporation of beta-streptococci into the microbiocenosis of highly permeable intestines (a pathogenic concept). Russian edition | q-bio.TO | A review of recent investigations into pathogenesis of psoriasis summarizing
data on the relationship between the presence beta-streptococci in the organism
and the cutaneous immune reaction. Results of the studies on gastrointestinal
pathology in psoriatic patients are presented. The authors propose a hypothesis
that ... | biology |
5,765 | Pattern formation in auxin flux | q-bio.TO | The plant hormone auxin is fundamental for plant growth, and its spatial
distribution in plant tissues is critical for plant morphogenesis. We consider
a leading model of the polar auxin flux, and study in full detail the stability
of the possible equilibrium configurations. We show that the critical states of
the auxi... | biology |
5,766 | Dinamics of HPV Infection among Women with Cervical Lesions | q-bio.TO | A total of 293 women treated at Tomsk Cancer Research Institute were
examined. HPV type 16 had the highest incidence rate (45.0%) followed by HPV
31-17,0%, HPV 56/33-15,0%, HPV 51/18/52-13,0%, HPV 58/35/39/45-7,0%, HPV
59-5,0%. Persistent infection was detected in 35.7% of primarily HPV-positive
cases (10 out of 28 pat... | biology |
5,767 | The cellular dynamics of bone remodeling: a mathematical model | q-bio.TO | The mechanical properties of vertebrate bone are largely determined by a
process which involves the complex interplay of three different cell types.
This process is called {\it bone remodeling}, and occurs asynchronously at
multiple sites in the mature skeleton. The cells involved are bone resorbing
osteoclasts, bone m... | biology |
5,768 | Propagating left/right asymmetry in the zebrafish embryo: one-dimensional model | q-bio.TO | During embryonic development in vertebrates, left-right (L/R) asymmetry is
reliably generated by a conserved mechanism: a L/R asymmetric signal is
transmitted from the embryonic node to other parts of the embryo by the L/R
asymmetric expression and diffusion of the TGF-$\beta$ related proteins Nodal
and Lefty via propa... | biology |
5,769 | In vitro and in vivo antileishmanial efficacy of a combination therapy of diminazene and artesunate against Leishmania donovani in BALB /c mice | q-bio.TO | The in vitro and in vivo activity of diminazene (Dim), artesunate (Art) and
combination of Dim and Art (Dim-Art) against Leishmania donovani was compared
to reference drug; amphotericin B. IC50 of Dim-Art was found to be $2.28 \pm
0.24 \mu$ g/mL while those of Dim and Art were $9.16 \pm 0.3 \mu$ g/mL and
$4.64 \pm 0.48... | biology |
5,770 | The Fundamental Theorem of Phyllotaxis revisited | q-bio.TO | Jean's `Fundamental Theorem of Phyllotaxis' (\emph{Phyllotaxis: a systematic
study in Plant Morphogenesis}, CUP 1994) describes the relationship between the
count numbers of observed spirals in cylindrical lattices and the horizontal
angle between vertically successive spots in the lattice. It is indeed
fundamental to ... | biology |
5,771 | Simulating Organogenesis in COMSOL | q-bio.TO | Organogenesis is a tightly regulated process that has been studied
experimentally for decades. Computational models can help to integrate
available knowledge and to better understand the underlying regulatory logic.
We are currently studying mechanistic models for the development of limbs,
lungs, kidneys, and bone. We ... | biology |
5,772 | Branch Mode Selection during Early Lung Development | q-bio.TO | Many organs of higher organisms, such as the vascular system, lung, kidney,
pancreas, liver and glands, are heavily branched structures. The branching
process during lung development has been studied in great detail and is
remarkably stereotyped. The branched tree is generated by the sequential,
non-random use of three... | biology |
5,773 | Immunomodulatory role of an Ayurvedic formulation on imbalanced immune-metabolics during inflammatory responses of obesity and pre-diabetic disease | q-bio.TO | Obesity and related type 2 diabetes are associated with a low level chronic
inflammatory state with disease status increasing at epidemic proportions
worldwide. It is now universally accepted that the underlying
immune-inflammatory responses mediated within the adipose tissue in obesity are
central to the development o... | biology |
5,774 | The effect of low doses of cadmium and zinc chloride on the Blood-Testis Barrier of Sprague Dawley rats | q-bio.TO | Background: Cadmium chloride is an environmental toxic that affects the male
reproductive system. This study was directed 1) to evaluate whether long-term
oral exposures to low doses of Cd in rats causes morphological changes, 2) the
immunohistochemical TJ and AJ protein expression; and 3) to evidence that zinc
exposur... | biology |
5,775 | Immunoexpression of Nm23: correlation with traditional prognostic markers in breast carcinoma | q-bio.TO | Fifty cases of breast carcinoma were investigated for Nm23, LPA1, Ki67 and
p53 antigen expression, using immunohistochemical techniques. Correlation
between markers was studied. Nm23 showed an inverse correlation with LPA1 and
Ki67, and positive with p53. Nm23/LPA1presented significant (p<0.001) negative
correlation wi... | biology |
5,776 | On applications of conservation laws in pharmacokinetics | q-bio.TO | There has been certain criticism raised by A. Rescigno [2,8,9,12-15] against
the standard formulation of pharmacokinetics. In 2011 it has been suggested
that inconsistencies in pharmacokinetics should be eliminated after deriving
"pharmacokinetic parameters" from conservation laws [3]. In the following text
a simple sy... | biology |
5,777 | On the Way to More Convenient Description of Drug-Plasma Protein Binding | q-bio.TO | The theoretical case is considered where the total amount of plasma protein
is conserved, but the drug is eliminated after its single application. After a
single drug application at time t = 0, the total drug concentration is measured
at times ti,...,tk and the total drug concentration at time ti is denoted by
{\phi}i.... | biology |
5,778 | The model muddle: in search of tumour growth laws | q-bio.TO | In this article we shall trace the historical development of tumour growth
laws, which in a quantitative fashion describe the increase in tumour
mass/volume over time. These models are usually formulated in terms of
differential equations that relate the growth rate of the tumour to its current
state, and range from th... | biology |
5,779 | The Flexibility and Musculature of the Ostrich Neck: Implications for the Feeding Ecology and Reconstruction of the Sauropoda (Dinosauria:Saurischia) | q-bio.TO | The Sauropoda were the largest terrestrial animals ever to have lived on this
planet. As their nutritional requirements were so huge, their diet holds sway
over the ecology of many Mesozoic herbivores. The diet of the sauropods is
limited by their feeding envelope, which in turn is governed by the posture and
flexibili... | biology |
5,780 | Aspects of the history, anatomy, taxonomy and palaeobiology of sauropod dinosaurs | q-bio.TO | Although the sauropod dinosaurs have been recognised for more than a hundred
and sixty years, much remains to be discovered and understood about their
functional anatomy and palaeobiology. Older taxa require revision and new taxa
await description. The characteristic long necks of sauropods are mechanically
perplexing ... | biology |
5,781 | Computational and Experimental Study of the Mechanics of Embryonic Wound Healing | q-bio.TO | Wounds in the embryo show a remarkable ability to heal quickly without
leaving a scar. Previous studies have found that an actomyosin ring ("purse
string") forms around the wound perimeter and contracts to close the wound over
the course of several dozens of minutes. Here, we report experiments that
reveal an even fast... | biology |
5,782 | Senescent fibroblasts can drive melanoma initiation and progression | q-bio.TO | Skin is one of the largest human organ systems whose primary purpose is the
protection of deeper tissues. As such, the skin must maintain a homeostatic
balance in the face of many microenvironmental and genetic perturbations. At
its simplest, skin homeostasis is maintained by the balance between skin cell
growth and de... | biology |
5,783 | WARN: an R package for quantitative reconstruction of weaning ages in archaeological populations using bone collagen nitrogen isotope ratios | q-bio.TO | Nitrogen isotope analysis of bone collagen has been used to reconstruct the
breastfeeding practices of archaeological human populations. However, weaning
ages have been estimated subjectively because of a lack of both information on
subadult bone collagen turnover rates and appropriate analytical models. Here,
we prese... | biology |
5,784 | A Systems Model of the Eco-physiological Response of Plants to Environmental Heavy Metal Concentrations | q-bio.TO | The ecophysiological response of plants to environmental heavy metal stress
is indicated by the profile of its tissue HM concentrations (Cp) versus the
concentration of the HM in the substrate (Cs). We report a systems biology
approach to the modelling of the Cp- Cs profile using as loose analogy, the
Verhulst model of... | biology |
5,785 | Arterial stiffening provides sufficient explanation for primary hypertension | q-bio.TO | Hypertension is one of the most common age-related chronic diseases and by
predisposing individuals for heart failure, stroke and kidney disease, it is a
major source of morbidity and mortality. Its etiology remains enigmatic despite
intense research efforts over many decades. By use of empirically
well-constrained com... | biology |
5,786 | Mathematical modeling of the metastatic process | q-bio.TO | Mathematical modeling in cancer has been growing in popularity and impact
since its inception in 1932. The first theoretical mathematical modeling in
cancer research was focused on understanding tumor growth laws and has grown to
include the competition between healthy and normal tissue, carcinogenesis,
therapy and met... | biology |
5,787 | Travelling wave analysis of a mathematical model of glioblastoma growth | q-bio.TO | In this paper we analyse a previously proposed cell-based model of
glioblastoma (brain tumour) growth, which is based on the assumption that the
cancer cells switch phenotypes between a proliferative and motile state (Gerlee
and Nelander, PLoS Comp. Bio., 8(6) 2012). The dynamics of this model can be
described by a sys... | biology |
5,788 | Compartmental analysis of nuclear imaging data for the quantification of FDG liver metabolism | q-bio.TO | This paper utilizes compartmental analysis and a statistical optimization
technique in order to reduce a compartmental model describing the metabolism of
labelled glucose in liver. Specifically, we first design a compartmental model
for the gut providing as output the tracer concentration in the portal vein.
This quant... | biology |
5,789 | Reduction of breast cancer relapses with perioperative non-steroidal anti-inflammatory drugs: new findings and a review | q-bio.TO | To explain a bimodal pattern of hazard of relapse among early stage breast
cancer patients identified in multiple databases, we proposed that late
relapses result from steady stochastic progressions from single dormant
malignant cells to avascular micrometastases and then on to growing deposits.
However in order to exp... | biology |
5,790 | Inter-dependent Tissue Growth and Turing Patterning in a Model for Long Bone Development | q-bio.TO | The development of long bones requires a sophisticated spatial organization
of cellular signaling, proliferation, and differentiation programs. How such
spatial organization emerges on the growing long bone domain is still
unresolved. Based on the reported biochemical interactions we developed a
regulatory model for th... | biology |
5,791 | Fractal growth of tumors and other cellular populations: Linking the mechanistic to the phenomenological modeling and vice versa | q-bio.TO | In this paper we study and extend the mechanistic mean field theory of growth
of cellular populations proposed by Mombach et al in (Mombach J. C. M. et al.,
Europhysics Letter, 59 (2002) 923) (MLBI model), and we demonstrate that the
original model and our generalizations lead to inferences of biological
interest. In t... | biology |
5,792 | A non-linear mathematical model of cell turnover, differentiation and tumorigenesis in the intestinal crypt | q-bio.TO | We present a development of a model of the relationship between cells in
three compartments of the intestinal crypt: stem cells, semi-differentiated
cells and fully differentiated cells. Stem and semi-differentiated cells may
divide to self-renew, undergo programmed death or progress to
semi-differentiated and fully di... | biology |
5,793 | A general framework for modeling tumor-immune system competition and immunotherapy: mathematical analysis and biomedical inferences | q-bio.TO | In this work we propose and investigate a family of models, which admits as
particular cases some well known mathematical models of tumor-immune system
interaction, with the additional assumption that the influx of immune system
cells may be a function of the number of cancer cells. Constant, periodic and
impulsive the... | biology |
5,794 | A filter-flow perspective of hematogenous metastasis offers a non-genetic paradigm for personalized cancer therapy | q-bio.TO | Research into mechanisms of hematogenous metastasis has largely become
genetic in focus, attempting to understand the molecular basis of `seed-soil'
relationships. Preceeding this biological mechanism is the physical process of
dissemination of circulating tumour cells (CTCs). We utilize a `filter-flow'
paradigm to sho... | biology |
5,795 | Precision and reproducibility of macroscopic developmental patterns | q-bio.TO | Developmental processes in multicellular organisms occur far from
equilibrium, yet produce complex patterns with astonishing reproducibility. We
measure the precision and reproducibility of bilaterally symmetric fly wings
across the natural range of genetic and environmental conditions and find that
wing patterns are s... | biology |
5,796 | Overt and covert paths for sound in the auditory system of mammals | q-bio.TO | The consensus, according to which the transmission of sound from the tympanum
to the Outer Hair Cells is solely mechanical, is problematic, especially with
respect to high pitched sounds. We demonstrate that the collagenous fibers of
the tympanum produce electric potentials synchronous to acoustic vibrations and
that, ... | biology |
5,797 | Modeling and Simulation of the Effects of Cyclic Loading on Articular Cartilage Lesion Formation | q-bio.TO | We present a model of articular cartilage lesion formation to simulate the
effects of cyclic loading. This model extends and modifies the
reaction-diffusion-delay model by Graham et al. 2012 for the spread of a lesion
formed though a single traumatic event. Our model represents "implicitly" the
effects of loading, mean... | biology |
5,798 | A Bayesian approach to accounting for variability in mechanical properties in biomaterials | q-bio.TO | In this paper, we present an approach for modeling bio-tissues that
incorporates the variability in properties as part of their characteristics.
This is achieved by considering the parameters of the model of a biomaterial to
themselves be random variables and represented by a probability distribution
over the space of ... | biology |
5,799 | Fine temporal structure of cardiorespiratory synchronization | q-bio.TO | Cardiac and respiratory rhythms are known to exhibit a modest degree of phase
synchronization, which is affected by age, diseases, and other factors. We
study the fine temporal structure of this synchrony in healthy young, healthy
elderly, and elderly subjects with coronary artery disease. We employ novel
time-series a... | biology |
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