The concentration of selected elements in the placenta according to selected sociodemographic factors and their effect on birth mass and birth length of newborns

Background and aimsThe placenta is a remarkable organ which provides critical transport functions between the maternal and fetal circulations during pregnancy. The demand for mineral components increases during the gestational period, therefore, an appropriate intake of minerals, such as calcium, phosphorus, potassium, magnesium, iron, zinc, copper, and manganese, determines the correct growth and development of a fetus. The aim of the study was to assess the concentration of selected elements in the placenta, and to assess the impact of their concentrations on the birth weight and birth length of newborns. The second aim of the study was to assess the influence of selected sociodemographic factors on the concentration of elements in the placenta.ResultsThe study demonstrated that the age of mothers affected the concentration of Ca and Mn in the placenta, and their habit of tobacco smoking during the gestational period was associated with higher concentrations of Ca, P, K, Mg, Fe, Cu, and Cd in the placental tissue. The results also showed that concentrations of K, Fe, Zn, and Mn in the placental tissue affected birth length. Furthermore, the association was demonstrated between a higher Cd concentration in the placenta (≥ 0.0503 μg/g) and the birth anthropometric parameters of neonates.ConclusionsSmoking during pregnancy and environment pollution are the factors that affects the concentration of elements in the placenta and contributes to their high accumulation in the placenta. Smoking during pregnancy causes an increased concentration of cadmium in the placenta which has negative health effects for the newborn. Women living in a big city or village had a higher concentration of cadmium in their placentas compared to women living in smaller cities. The significant influence of some elements (K, Fe, Zn, Cu and Cd) on the newborn’s birth parameters was also demonstrated. The results of our research indicate the importance of the mother’s lifestyle in providing the placenta with elements, which affects the growth of the fetus.

• •The placenta is an organ that is responsible for the proper course of pregnancy and fetal development.
• •The demand for mineral components increases during the gestational period, therefore, an appropriate intake of minerals determines the correct growth and development of a fetus
• •Increased exposure to arsenic, cadmium and lead during the gestational period can induce miscarriage, premature delivery, risk of fetal death, inhibition of intrauterine growth and development of the fetus, and low birth parameters.

     

Translational Control of the Picornavirus Phenotype

Picornaviruses are small animal viruses with positive-strand genomic RNA, which is translated using cap-independent internal translation initiation. The key role in this is played by ciselements of the 5"-untranslated region (5"-UTR) and, in particular, by the internal ribosome entry site (IRES). The function of translational ciselements requires both canonical translation initiation factors (eIFs) and additional IRES trans-acting factors (ITAFs). All known ITAFs are cell RNA-binding proteins which play a variety of functions in noninfected cells. Specific features of translational ciselements substantially affect the phenotype and, in particular, tissue tropism and pathogenic properties of picornaviruses. It is clear that, in some cases, the molecular mechanism involved is a change in interactions between viral ciselements and ITAFs. The properties and tissue distribution of ITAFs may determine the biological properties of other viruses that also use the IRES-dependent translation initiation. Since this mechanism is also involved in translation of several cell mRNAs, ITAF may contribute to the regulation of the most important aspects of the living activity in noninfected cells.     

基于微波热声层析成像定量重建生物组织电导率的改进方法

目的 生物电磁学参数中的电导率与组织的功能性信息直接相关,精准重建生物组织电导率在医学成像技术和医学诊断领域中有着重要意义。本文改进定量微波热声层析成像（microwave-induced thermoacoustic tomography,MTAT）算法,使组织电导率的重建精度提高。方法 本文在利用有限元离散法求解热声波动方程和亥姆霍兹方程的基础之上,提出了一种基于正则化牛顿迭代法（regularized Newton iteration method,RNIM）定量重建组织电导率的改进方法。结果 通过数值模拟实验和含不同浓度NaCl溶液的仿体实验,验证了算法改进的有效性。组织仿体实验结果表明,目标在不同位置、不同大小、不同对比度情况下,相比于定量微波热声层析成像采用拟合（fitting）的方法,采用正则化牛顿法定量重建的仿体电导率相对误差明显降低,重建目标精度提高。在仿体实验中采用RNIM方法重建相同浓度的单目标在不同位置的电导率变化幅度更小,以及重建多目标电导率的相对比值与实际更接近,实验结果验证了改进方法的稳定性。结论 研究结果表明优化算法能更加准确地定量重建组织仿体的电导率,...     

A photo-cross-linking approach to monitor protein dynamics in living cells

BackgroundProteins, which comprise one of the major classes of biomolecules that constitute a cell, interact with other cellular factors during both their biogenesis and functional states. Studying not only static but also transient interactions of proteins is important to understand their physiological roles and regulation mechanisms. However, only a limited number of methods are available to analyze the dynamic behaviors of proteins at the molecular level in a living cell. The site-directed in vivo photo-cross-linking approach is an elegant technique to capture protein interactions with high spatial resolution in a living cell.Scope of reviewHere, we review the in vivo photo-cross-linking approach including its recent applications and the potential problems to be considered. We also introduce a new in vivo photo-cross-linking-based technique (PiXie) to study protein dynamics with high spatiotemporal resolution.Major conclusionsIn vivo photo-cross-linking enables us to capture weak/transient protein interactions with high spatial resolution, and allows for identification of interacting factors. Moreover, the PiXie approach can be used to monitor rapid folding/assembly processes of proteins in living cells.General significanceIn vivo photo-cross-linking is a simple method that has been used to analyze the dynamic interactions of many cellular proteins. Originally developed in Escherichia coli, this system has been extended to studies in various organisms, making it a fundamental technique for investigating dynamic protein interactions in many cellular processes. This article is part of a Special issue entitled “Novel major techniques for visualizing ‘live’ protein molecules” edited by Dr. Daisuke Kohda.     

Model membrane platforms to study protein-membrane interactions

Abstract

Constituting functional interactions between proteins and lipid membranes is one of the essential features of cellular membranes. The major challenge of quantitatively studying these interactions in living cells is the multitude of involved components that are difficult, if not impossible, to simultaneously control. Therefore, there is great need for simplified but still sufficiently detailed model systems to investigate the key constituents of biological processes. To specifically focus on interactions between membrane proteins and lipids, several membrane models have been introduced which recapitulate to varying degrees the complexity and physicochemical nature of biological membranes. Here, we summarize the presently most widely used minimal model membrane systems, namely Supported Lipid Bilayers (SLBs), Giant Unilamellar Vesicles (GUVs) and Giant Plasma Membrane Vesicles (GPMVs) and their applications for protein-membrane interactions.     

Human biomonitoring of 73 elements in blood,serum, erythrocytes and urine

BackgroundHuman biomonitoring studies of trace elements in biological fluids are mostly limited to a certain number of elements or biological materials. In this study, we describe the significant extension of a biomonitoring to 73 elements being present in concentration ranges from ng/L to g/L in clinically relevant specimens such as blood, serum, erythrocytes and urine.MethodsThe samples were collected from 102 occupationally non-exposed inhabitants of northern Germany. The elements were determined either by inductively coupled plasma tandem mass spectrometry (ICP-MS/MS) in the low concentration range or by inductively coupled plasma optical emission spectrometry (ICP-OES) for essential trace elements and electrolytes.ResultsMean values and selected percentiles of element concentrations are presented for all sample materials. From the results, we calculated the distribution of elements between plasma and blood cells. Application of ICP-MS/MS improves selectivity and accuracy in the determination of elements that are strongly spectrally interfered, such as Cr, Ge, Pd or Ti in blood samples.ConclusionsThis publication provides very valuable information for occupational or environmental hygienists, toxicologists and clinical chemists due to the particularly high number of determined elements and presented concentration ranges.     

Some Aspects of the Biology of Pilaira anomala—An Extremely Versatile Fungus

Abstract

This article describes the rationale for mathematical modelling and computer simulation of ecological systems, and suggests reasons why this is still a relatively unexplored field of biological education. Recently, inexpensive yet extremely versatile modular analogue computing systems have become available from UK suppliers of science teaching equipment. These are suggested as possible alternatives to digital machines for those wishing to introduce modelling and simulation into their teaching. The behaviour of an analogue computer and the operations it performs are described. The application of these ideas to the teaching of population ecology is then illustrated through analogue simulations of exponential growth, logistic growth, and predator-prey interactions. Typical results for each of these three models are presented.     

Quantitative autoradiography in boron neutron capture therapy considering the particle ranges in the samples

PurposeBoron neutron capture therapy is a cellular-scale particle therapy exploiting boron neutron capture reactions in boron compounds distributed in tumour cells. Its therapeutic effect depends on both the accumulation of boron in tumour cells and the neutron fluence. Autoradiography is used to visualise the micro-distribution of boron compounds.MethodsHere, we present an equation for the relationship between boron concentration and pit density on the solid-state nuclear track detector, taking into consideration the particle ranges in the samples. This equation is validated using liver-tissue sections and boron standard solutions. Moreover, we present a simple co-localisation system for pit and tissue-section images that requires no special equipment.ResultsThe equation reproduces the experimentally observed trends between boron concentration and pit density. This equation provides a theoretical explanation for the widely used calibration curve between pit density and boron concentration; it also provides a method to correct for differences of tissue-section thickness in quantitative autoradiography.ConclusionsUsing the equation together with this co-localisation system could improve micro-scale quantitative estimation in tissue sections.     

In situ structural biology using in-cell NMR

BackgroundAccumulating evidence from the experimental and computational studies indicated that the functional properties of proteins are different between in vitro and living cells, raising the necessity to examine the protein structure under the native intracellular milieu. To gain structural information of the proteins inside the living cells at an atomic resolution, in-cell NMR method has been developed for the past two decades.Scope of reviewIn this review, we will overview the recent progress in the methodological developments and the biological applications of in-cell NMR, and discuss the advances and challenges in this filed.Major conclusionsA number of methods were developed to enrich the isotope-labeled proteins inside the cells, enabling the in-cell NMR observation of bacterial cells as well as eukaryotic cells. In-cell NMR has been applied to various biological systems, including de novo structure determinations, protein/protein or protein/drug interactions, and monitoring of chemical reactions exerted by the endogenous enzymes. The bioreactor system, in which the cells in the NMR tube are perfused by fresh culture medium, enabled the long-term in-cell NMR measurements, and the real-time observations of intracellular responses upon external stimuli.General significanceIn-cell NMR has become a unique technology for its ability to obtain the function-related structural information of the target proteins under the physiological or pathological cellular environments, which cannot be reconstituted in vitro.     

Stochastic prey-predator relationships: A random differential equation approach

A stochastic model describing two interacting populations is considered. The model involves a random differential equation of the form dX/dt=A(t)X+Y(t) where the random matrixA and vectorY represent the interactions and growth rates respectively andX is a (random) vector the components of which are the logarithms of the population's sizes. An expression for the solution of the above equation is obtained whence its statistical properties can be determined. Alternatively, a method based on Liouville's theorem is used to obtain the probability distribution of the solution. Application of both methods to simple cases indicates that the random solution is asymptotically stable in the mean even when the solution to the associated deterministic equation is not, viz. in the absence of self interactions.     

SD大鼠骨髓间充质干细胞分离培养及鉴定的实验研究

摘要 目的：探讨应用全骨髓贴壁法体外分离培养SD大鼠骨髓间充质干细胞（BMSCs)的可行性,研究其生物学特性,为骨组织工程提供种子细胞。方法：取SPF级5周龄健康SD大鼠2只,脱颈处死,分离双下肢股骨、胫骨,全骨髓贴壁法分离培养、纯化BMSCs;通过倒置显微镜观察原代、传代细胞生长情况、绘制生长、贴壁率曲线,研究其生物学特性;流式细胞仪检测表面标志物、诱导成成骨等方法进行鉴定。结果：应用全骨髓贴壁法可在体外分离出活性好、纯度高的BMSCs。倒置显微镜下可见原代细胞呈梭形、多角形,传代细胞形态均一呈纤维样;P3代BMSCs经流式细胞鉴定：CD44、CD90高表达,CD31、CD45低表达;定向诱导向成骨细胞分化,可见明显矿化结节。结论：证实应用全骨髓贴壁培养法体外可成功分离BMSCs,所分离培养、纯化的细胞生物学稳定,纯度高、活性好,具有多向分化潜能,能为骨组织工程、骨质疏松症和骨折不愈合疾病的研究提供种子细胞。     

Molecular dynamics simulation of proteins under high pressure: Structure,function and thermodynamics

BackgroundMolecular dynamics (MD) simulation is well-recognized as a powerful tool to investigate protein structure, function, and thermodynamics. MD simulation is also used to investigate high pressure effects on proteins. For conducting better MD simulation under high pressure, the main issues to be addressed are: (i) protein force fields and water models were originally developed to reproduce experimental properties obtained at ambient pressure; and (ii) the timescale to observe the pressure effect is often much longer than that of conventional MD simulations.Scope of reviewFirst, we describe recent developments in MD simulation methodologies for studying the high-pressure structure and dynamics of protein molecules. These developments include force fields for proteins and water molecules, and enhanced simulation techniques. Then, we summarize recent studies of MD simulations of proteins in water under high pressure.Major conclusionsRecent MD simulations of proteins in solution under pressure have reproduced various phenomena identified by experiments using high pressure, such as hydration, water penetration, conformational change, helix stabilization, and molecular stiffening.General significanceMD simulations demonstrate differences in the properties of proteins and water molecules between ambient and high-pressure conditions. Comparing the results obtained by MD calculations with those obtained experimentally could reveal the mechanism by which biological molecular machines work well in collaboration with water molecules.     

In-cell single-molecule FRET measurements reveal three conformational state changes in RAF protein

BackgroundThe structures of proteins are intimately related to their functions. Significant efforts have been dedicated to the structural investigation of proteins, mainly those of purified proteins in in vitro environments. Proteins function in living cells and thus protein structures must be regulated by interactions with various molecules, some of which participate in reaction networks, depending on the states, conditions, or actions of the cell. Therefore, it is very important to understand the structural behavior of proteins in living cells.MethodsSingle-molecule Förster resonance energy transfer (smFRET) measurements were conducted using the alternative laser excitation (ALEX) technique. smFRET distributions of cytosolic Rapidly Accelerated Fibrosarcoma (RAF) proteins in living HeLa cells were obtained with exclusion of the negative effects of photobleached fluorophores and incompletely labeled proteins on smFRET.ResultssmFRET histograms of wildtype (wt) RAF in live cells exhibited two major peaks, whereas that of the S621A mutant, which has been thought to have an expanded structure, was almost single-peaked. A population shift involving the peaks for wt RAF was detected upon epidermal growth factor stimulation. Spontaneous transitions between the conformational states corresponding to the two peaks were also detected using the FRET-two-channel kernel-based density distribution estimator method in comparison to static double-stranded DNA samples.ConclusionsCytosolic CRAF has at least three conformational states; in addition to the closed and open forms, the fully-open form was distinctly specified. Based on the results, we propose a speculative structural model for CRAF.General significanceStructural distribution and changes to proteins in live cells as a result of intracellular interactions were successfully identified. smFRET using ALEX is applicable to any other cytosolic proteins.     

土壤细菌网络互作调控线虫肠道细菌群落

动物肠道细菌群落在联系宿主与生态系统功能中发挥着至关重要的作用。【目的】本研究旨在评估绿肥翻压和水稻生长不同时期对土壤细菌和线虫肠道细菌群落组成和结构的影响,并探究土壤细菌和线虫肠道细菌群落间的潜在关联关系。【方法】基于盆栽试验,结合16S rRNA基因高通量测序技术,分析黑麦草翻压和对照处理下水稻生长的前期(返青期)和后期(收获期)土壤细菌和线虫肠道细菌群落,结合网络分析研究土壤细菌网络互作对线虫肠道细菌群落的潜在影响。【结果】黑麦草翻压对土壤细菌和线虫肠道细菌群落组成和结构没有显著影响(P>0.05);水稻生长后期样品比前期样品具有更高的α多样性。基于随机森林机器学习法获得的土壤细菌和线虫肠道细菌生物标志物之间存在广泛的显著相关关系,为土壤细菌群落变化调控线虫肠道细菌群落组成提供了有力的证据。共现网络分析表明土壤细菌之间的正相互作用显著促进了土壤细菌和线虫肠道细菌之间的正相互作用(P<0.01),进而影响了线虫肠道细菌之间的网络互作。结构方程模型进一步表明土壤养分含量的降低主要通过降低土壤细菌之间正相互作用,从而间接影响线虫肠道细菌之间的互作。【结论】土壤细菌互作可能在...     

Analysis of human tissues using Energy Dispersive X Ray Fluorescence – Dark matrix determination for the application to cancer research

BackgroundX ray Fluorescence has been essayed as a suitable technique for the elemental quantification of trace element in human tissues, namely comparison of normal and cancerous tissue. However, accurate results depend on a robust quantification approach, namely correct evaluation of the samples’ dark matrix.MethodsIn order to determine the most suitable dark matrix composition for the quantification of such samples using the Fundamental Parameter approach, we have measured several Certified Reference Materials and essayed different dark matrix compositions to achieve the most accurate results. The resulting dark matrix was then applied to normal and tumor ovarian and prostate tissue samples, and the obtained results were compared with the ones obtained with a comparative method using external standard calibration curves.ResultsUsing a dark matrix composed of 10 % - H, 22 % - C, 3 % - N and 60 % - O yielded the best compromise in accuracy for the light and heavy elements. For the reduced sample size and conditions of this study, for both organs, the concentrations of transition metals decrease in tumor tissues, while the concentration of lighter elements, P and Cl, increases. On the other hand, there are elements that showed different behavior between the two types of tissue, namely Zn and S, that increase in prostate tumor tissue and decrease in ovarian tissue.ConclusionAn increase in precision was one of the improvements found with the newly developed method, as the FP-approach contemplates matrix effects and the influence of other elements in the analytes’ quantification. Additionally, the determined dark matrix can be employed in any tissue analysis application by means of EDXRF.     

Interactions Between Soluble Enzymes and Subcellular Structur

Abstract

Soluble enzymes contribute significantly to the metabolic capabilities of living organisms, but it is becoming increasingly clear that the activities of these enzymes are significantly modified by their interactions with structural components of the cell, and that these interactions may make important contributions to metabolic regulation. In the past, specification of these interactions has been limited by the availability of suitable experimental techniques, but this deficiency is now being rectified and our understanding of these processes is advancing rapidly. Research in this area is moving into a second phase, with the emphasis no longer being focused on demonstrations of the biological reality of these interactions, but directed more towards quantitative aspects of binding, the determination of the characteristics of binding domains, and the theoretical basis of regulatory involvements. All of these aspects are discussed in the present review.     

A structural approach to the role of CCN (CYR61/CTGF/NOV) proteins in tumourigenesis

The CCN (CYR61 [Cystein-rich61]/CTGF [connective tissue growth factor]/NOV [Nephroblastoma overexpressed]) proteins constitute a family of regulatory factors involved in many aspects of cell proliferation and differentiation. An increasing body of evidence indicates that abnormal expression of the CCN proteins is associated to tumourgenesis. The multimodular architecture of the CCN proteins, and the production of truncated isoforms in tumours, raise interesting questions regarding the participation of each individual module to the various biological properties of these proteins. In this article, we review the current data regarding the involvement of CCN proteins in tumourigenesis. We also attempt to provide structural basis for the stimulatory and inhibitory functions of the full length and truncated CCN proteins that are expressed in various tumour tissues.     

整合受体调控基因表达信息构建细胞通信网络

目的 构建细胞通信网络有助于揭示细胞间协同工作机制、生物学过程和疾病发病机理。目前基于配体-受体相互作用构建细胞通信网络的方法大多只考虑配体和受体的表达信息，忽略了受体对其调控基因的信号传递影响，导致构建的细胞通信网络可靠性较低。鉴于此，本文提出IRRG算法，旨在构建更为准确的细胞通信网络，并挖掘具有生物学意义的细胞通信模式。方法 本文提出了一种整合受体调控基因表达信息构建细胞通信网络的方法（命名为IRRG）。该方法通过随机游走方式计算受体对下游基因的影响得分，进而与配体-受体共表达量结合构建细胞通信网络。结果 使用IRRG构建了小鼠滤泡间表皮（IFE）细胞通信网络并分析了配体-受体对的生物学意义，验证了IRRG计算受体影响得分的稳定性和细胞通信网络构建的可靠性。此外，使用IRRG构建了透明细胞肾细胞癌（ccRCC）的细胞通信网络，挖掘并分析其肿瘤微环境细胞通信模式。结论 IRRG可以构建富有生物学意义并且可靠的细胞通信网络，帮助人们从细胞通信的角度更深入地了解多种生物过程。IRRG算法代码可从GitHub获取：https://github.com/NWPU-903PR/IRRG。