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Copyright of Advances in Biochemistry / Postepy Biochemii is the property of Polish Biochemical Society / Acta Biochimica Polonica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Polish Journal of Allergology / Alergologia Polska is the property of Termedia Publishing House and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Advances in Biochemistry / Postepy Biochemii is the property of Polish Biochemical Society / Acta Biochimica Polonica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Progress in Plant Protection is the property of Institute of Plant Protection and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Mesenchymal stem cells are characterized by an enormous regenerative potential, and are widely used for various indications. They secrete a number of growth factors, including those for fibroblasts, endothelium, as well as anti-inflammatory cytokines. Furthermore, they also stimulate tissue regeneration, thus, promoting the secretion of proteins and glycosaminoglycans of extracellular matrices, such as collagen I, II, III and V, elastin, but also metalloproteinases. They secrete exosomes and microbubbles which contain proteins, nucleic acids, lipids, and enzymes. In addition, they present a free radical-inactivating effect. The aim of this study was to collect the existing literature with regard to the use of stem cells in the treatment of burn wounds. [ABSTRACT FROM AUTHOR]

Copyright of Advances in Biochemistry / Postepy Biochemii is the property of Polish Biochemical Society / Acta Biochimica Polonica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The year 1961 went down in history with exceptional scientific achievements. On May 13, the journal Nature published two articles on the first isolation of messenger ribonucleic acid (mRNA), which is an intermediate product between a gene and a protein. Just two weeks later, on May 27, the first letter of the genetic code, phenylalanine, was discovered. These discoveries made it possible to understand how genetic information is encoded and processed, thus causing the dynamic development of molecular biology. The breakthroughs of 1961 concerned not only nucleic acids. On April 12, the first human, Yuri Gagarin, entered space. Eight years later, in 1969, Neil Armstrong made his first walk on the moon, uttering the famous phrase: It is a small step for man, but a great leap for humanity. The era of conquering and learning about the cosmos has begun, mainly motivated by the natural curiosity of man and the desire to learn about the surrounding reality. The environmental factors in space are very different from terrestrial conditions, which raises questions about their effects on living organisms. In search of answers, a variety of scientific research has been carried out at the International Space Station (ISS) for over twenty years. As space travel is set to become more common in the near future, detailed studies of the effects of long-term space missions on the human body are required. These studies are currently carried out, among others using molecular biology techniques that enable detailed analysis of nucleic acids and proteins, but not only. The breakthrough achievements of 1961 initiated the development both in the field of molecular biology and the science of space, thanks to which today, 60 years after those events, we can combine knowledge and technological achievements from both fields to analyze and understand changes at the molecular level that occur as a result of being in organisms in outer space.

Iron is an essential micronutrient for the proper functioning of most organisms. This element is used in oxygen transport, myelin and neurotransmitters synthesis, cell cycle and synthesis of nucleic acids. The importance of iron in the maturation of lymphocytes and proper functioning of the eye is also stressed. Newborns are particularly sensitive to imbalances in iron metabolism. Iron deficiency during pregnancy carries serious clinical consequences. It seems that a key role in the transport of iron between mother and fetus is plays by hepcidin and, described in 2010 zyklopen. The physiological role of proteins involved in iron metabolism and transport of this metal by the placenta are described in this paper. [ABSTRACT FROM AUTHOR]

Glycation consists in formation of advanced glycation end-products (AGE) during non-enzymatic reaction between reducing sugars and proteins, lipids or nucleic acids. This review is focused mainly on glycation of collagen and its role in acceleration of vascular disease. Collagen is an extracellular matrix protein characterized by unique structure forming fibrils with great anti-tensile and anti-breaking strength. The protein builds the connective tissue and is responsible for biomechanical properties of blood vessels. It is reported that higher content of glycated collagen correlates with lower elasticity and greater toughness of the vessel walls and, as a consequence, a faster rate of atherosclerosis development. Numerous mechanisms connected with AGE formation are involved in atherogenesis, among others: receptor-mediated production of free radicals, triggering an inflammatory process, activation of leukocytes and thrombocytes, facilitation of LDL binding, change in level of growth factors, adhesion molecules, MMP and some other proteins' expression. The coverages allow the development of therapeutic strategies to prevent or slow down the pathological processes connected with glycation of collagen and other proteins in the artery wall. The main strategies are based on limitation of exogenous AGE, consumption of products which contain rutin, treatment with drugs which inhibit AGE formation, such as pyridoxamine, and chemicals which are able to cleave already formed AGE protein-protein crosslinks, such as ALT-711. [ABSTRACT FROM AUTHOR]

The unique properties of spider silk such as strength, extensibility, toughness, biocompatibility and biodegradability are the reasons for the recent development in silk biomaterial technology. For a long time scientific progress was impeded by limited access to spider silk. However, the development of the molecular biology strategy was a breaking point in synthetic spider silk protein design. The sequences of engineered spider silk are based on the consensus motives of the corresponding natural equivalents. Moreover, the engineered silk proteins may be modified in order to gain a new function. The strategy of the hybrid proteins constructed on the DNA level combines the sequence of engineered silk, which is responsible for the biomaterial structure, with the sequence of polypeptide which allows functionalization of the silk biomaterial. The functional domains may comprise receptor binding sites, enzymes, metal or sugar binding sites and others. Currently, advanced research is being conducted, which on the one hand focuses on establishing the particular silk structure and understanding the process of silk thread formation in nature. On the other hand, there are attempts to improve methods of engineered spider silk protein production. Due to acquired knowledge and recent progress in synthetic protein technology, the engineered silk will turn into intelligent biomaterial of the future, while its industrial production scale will trigger a biotechnological revolution. [ABSTRACT FROM AUTHOR]

Acute myeloid leukemia (AML) constitutes a group of diseases that are very heterogeneous with regard to clinical course, response to therapy as well as cytogenetic aberrations and gene mutations. Such lesions are of prognostic value. Patients with t(8;21), inv(16)/t(16;16) or t(15;17) have a favorable prognosis. Patients with normal karyotype and aberrations +6, +8 -Y, t(9;11) and del(12p) are classified in the group of intermediate prognosis. In the case of patients with complex karyotype or with the aberrations inv(3)/t(3;3), t(6;9), -5, -7, del(5q), del(7q) and 11q23 rearrangements, the prognosis is poor. Unfavorable molecular factors include C-MYC amplification, MLL amplification and rearrangement, FLT3-ITD, WT1 mutation and overexpression of BAALC, ERG or MN1. The changes in miRNA expression may also be important for AML prognosis. That is why the cases with normal karyotype (CN-AML) and cases with complex aberrations remain to be better characterized at the genetic level. Array technology enables the analysis of genomic DNA and gene expression. This approach may be used in the search for new prognostic and predictive markers in AML. [ABSTRACT FROM AUTHOR]

Congenital anomalies of the kidney and urinary tract (CAKUT) occur at a frequency of 1 in 500 live births and are a common cause of renal insufficiency in childhood. CAKUT encompass a wide spectrum of malformations including anomalies of the kidney, collecting system, bladder and urethra. Most cases of CAKUT are sporadic and limited to the urinary tract, but some of them are syndromic or associated with positive family history. To understand the basis of human renal anomalies, knowledge of kidney and urinary tract development is necessary. This process is very complicated, requires precise integration of a variety of progenitor cell populations of diverse embryonic origins and is controlled by many factors at every stage of development. This review focuses on the genetic factors leading to developmental errors of important morphogenetic processes, particularly in metanephric kidney induction and ureteric bud branching. The essential results of genetic studies in regard to CAKUT, performed on experimental models and in humans, are presented. However, further investigations are required to complete understanding of the complex molecular network, which will help us to determine novel preventive and therapeutic strategies for CAKUT [ABSTRACT FROM AUTHOR]

To date it has been impossible to establish borderline physical conditions which prevent HIV from infecting human cells. Full inactivation of the virus is not necessary to lose its capacity for infection - often damage of the mechanisms concerning e.g. HIV entry into the cell or integration with host DNA is sufficient. The presence of HIV RNA in a sample under certain conditions does not mean that the virions are infectious. Viral infectivity under certain conditions depends on temperature, humidity, sunlight, atmospheric pressure, pH of the environment, disinfectants, coagulation inhibitors, and the kind and amount of infectious biological material, especially HIV viremia in it. At present the influence of high temperature on HIV infectivity, inactivation or HIV RNA level is the best known phenomenon, while the influence of low temperature on the above parameters has been examined in less detail. In the paper the authors present the influence of various parameters on HIV infectivity, especially temperature variation [ABSTRACT FROM AUTHOR]

The functioning of an organism depends on the precise control mechanisms, constantly adjusted to the actual state. Therefore, there is a need for efficient communication between both adjacent and distant cells, which may be executed by proteins such as hormones, neurotransmitters and cytokines. Recently another means of regulation has emerged - short regulatory RNAs (srRNAs). Although discovered only a couple of years ago, the mechanism of RNA interference has already become a topic of thousands of publications, defining its roles in both physiological and pathological processes, such as cancerogenesis and autoimmunization. RNAs regulating cell function may be coded in its genome (both exons and introns) or be introduced from the external environment. In mammals microRNAs (miRNAs) cooperate with proteins from the Ago/PIWI family to form effector ribonucleoprotein complexes, and owing to their complementarity to the target mRNA, control genes' expression at the posttranscriptional level, either through the suppression of mRNA translation or through mRNA degradation. SrRNAs are crucial regulators throughout the development of immune cells, starting from hematopoietic stem cells, up to the effector cells of the adaptive immune response. Moreover, some of the regulatory cells perform their function by releasing miRNAs, which are then transported to the target cells, possibly enclosed in the exosomes [ABSTRACT FROM AUTHOR]

Melanoma is a tumour derived from melanocytes, cells of neuroectodermal origin. Melanoma treatment represents a challenge to oncologists due to its aggressive course and early and multiple metastases. Surgical excision of lesions is a highly effective intervention, but only in early stages. In contrast, median survival of patients with metastatic melanoma is still below one year. In 2011 the FDA and EMA have approved new drugs, ipilimumab and vemurafenib, that might be a major breakthrough in treating patients with advanced melanoma. However, time is needed to conclude whether they replace dacarbazine, a drug used for over 30 years in the therapy of metastatic melanoma, even if the response rate was only 10-15%. The mechanism of dacarbazine action is not clear but it is probably based on methylation of purine bases in DNA. The low therapeutic efficacy of dacarbazine might be the consequence of rapid removal of DNA lesions by repair systems. A high melanoma chemoresistance is also driven by the extent and nature of alterations in signal transductions in tumour cells. None of the previously conducted trials proved superiority of any treatment modality over monotherapy with dacarbazine. Higher response rates did not correlate with survival benefit, and more intense adverse effects were frequently observed. There are some expectations for targeted therapy and immunotherapy, which have already demonstrated some efficacy in clinical studies. This review aims at providing the current knowledge on dacarbazine and its analogue, temozolomide, including the latest results of clinical studies combining these drugs with other treatment protocols. [ABSTRACT FROM AUTHOR]

Acridines belong to a group of polycyclic heteroaromatic compounds and exhibit a broad spectrum of biological activity including antiprotozoal, antibacterial, antiviral and antitumor activity. Acridine derivatives with antitumor activity have different mechanisms of action at the molecular level. The data obtained so far indicate that one of the main steps is the formation of physicochemical complexes with DNA. Among acridine derivatives with anticancer activity we can distinguish five main classes of compounds: nitroacridines, 9-anilinoacridines, pyrazoloacridines, imidazoacridines, and triazoloacridines. Compounds from different classes differ both in mechanism of action and spectrum of antitumor activity. [ABSTRACT FROM AUTHOR]

The mammalian immune system has evolved several mechanisms that allow bacterial and viral infections to be successfully fought. Animal cells are able to recognize viral infection and this recognition is dependent on the presence of intracellular sensors that instantly identify danger signals and initiate signal cascades leading to an effective antiviral response. Several host proteins have been identified as intracellular sensors, namely: Toll-like receptors, RIG-I-like receptors, AIM2-like receptors and DAI, DNA-dependent activator of IFN regulatory factor. They recognize and bind viral genomic nucleic acids and all their replicative intermediates. Receptor-ligand interaction leads to activation of specific metabolic pathways that include synthesis and release of type I interferons and proinflammatory cytokines. These mediators are in turn responsible for synchronizing mechanisms of innate and adaptive antiviral immunity. They are crucial for blocking viral replication, preventing the spread of infection and eventually eliminating the virus from the host. Signaling pathways dependent on RIG-I, independent of TLR and other viral ligand(s) identification mechanisms leading to antiviral immune response stimulation, are discussed in this review. [ABSTRACT FROM AUTHOR]

This article focuses on the history of research on human mitochondrial DNA (mtDNA). Since 1963, when it was first detected within human mitochondrial cells, mtDNA has been an area of interest and research. The human mtDNA sequence was published in 1981, and the first pathogenic mtDNA mutations were identified in 1988 (large numbers of point mutations, deletions or duplications are characteristic of mitochondriopathies). Research regarding the role of mtDNA in human aging and the use of mtDNA in forensic and archeological studies is another area of interest. The issue of mtDNA inheritance, however, remains controversial. The author believes genetic counseling for mitochondriopathies is self-apparent, and supports the continuation of population base studies and using animal models in research.

Pancreatic cancer (PC) is one of the most aggressive malignancies. It is characterized by poor prognosis connected with very late detectability, low accessibility to resection and resistance to chemoradiotherapy. Only 10-20% of the cases are discovered during surgical resection phase. The process of PC carcinogenesis is a multi-step one. In the first phase, mutation occurs in protooncogenes K-ras (90-95% cases) and HER-2/neu. In the next phase, loss of functions occurs in suppressed genes: p16, p53, DPC4, and BRCA2. A new gene therapy against K-ras oncogene such as farnesyl transferase inhibitor (FTI) or antisense oligodeoxyribonucleotide (ODN) seems not to be effecitve enough in practice. RNA interference (RNAi) is a powerful tool to suppress gene expression. RNAi can be used against PC through an inhibition of K-ras oncogene, a suppression of tumor growth, of metastasis, and of an increase in apoptosis process. In this review, the practical applications of RNAi in PC, molecular consequences of silencing mutant K-ras, and novel methods of efficient delivery of small interfering RNA (siRNA) into cells are discussed. The described observations show that using siRNA against K-ras oncogene is effective in inhibiting its expression in vitro and in vivo and also point out that atelocollagen might be an effective carrier of nucleic acids (also RNAi) in gene therapy. [ABSTRACT FROM AUTHOR]

Many toxic or carcinogenic substances reveal their harmful properties only when activated to a compound with high affinity to nucleophylic groups, which are present in proteins and nucleic acids. After binding to DNA these compounds may induce carcinogenic mutation of genetic material. Increased activation or reduced detoxication of potentially carcinogenic xenobiotics disturbs cellular equlibrium and leads to carcinogenesis. Flavonoids and furanocoumarines contained in grapefruit juice were known to inhibit activity of many enzymes and were shown to inhibit in vitro activity of isoenzyme CYP2D6 with genetically induced polymophism. The aim of this work was to assess the significance of grapefruit juice flavonoids and furanocoumarines as chemopreventive factors against toxic and carcinogenic activity of xenobiotics with genetically determined metabolism by determining their influence on cytochrome P450 isoenzyme CYP2D6 activity. Material and metod. The trial included 32 healthy volunteers taking in grapefruit juice (16), orange juice (8) or fresh water (8). Oxidative phenotype and genotype were determined by analytic methods. Phenotype tests conducted prior to and after commencement of 5 days long intake of correspondingly grapefruit juice, orange juice or water revealed differences in metabolic ratio (MR) values among groups. Results. Grapefruit juice drinkers had mean value of metabolic ratio (MR) increased by 34%. Conclusions. Our investigation have shown that regular grapefriut juice consumption may be cosidered only as supportive measure against toxic and carcinogenic influence of environmental factors and industrial polution such as combustion gases, cigarette smoke and other toxic substances, particularly in patients with high risk of cancer. [ABSTRACT FROM AUTHOR]