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Open access

Adela Golea, Adriana Rusu, Christiana Dumulesc and Cornelia Bala

References 1. Mozaffarian D, Benjamin EJ, Go AS, Arnett DK, Blaha MJ, Cushman M, et al. Heart disease and stroke statistics-- 2015 update: a report from the American Heart Association. Circulation. 2015 Jan;131(4):e29-322. DOI: 10.1161/CIR.0000000000000152 2. Muller D, Agrawal R, Arntz HR. How sudden is sudden cardiac death? Circulation. Sep;114(11):1146-50. 3. Nichol G, Thomas E, Callaway CW, Hedges J, Powell JL, Aufderheide TP, et al. Regional variation in out-of-hospital cardiac arrest incidence and outcome

Open access

Vladimir Gasic, Biljana Stankovic, Branka Zukic, Dragana Janic, Lidija Dokmanovic, Nada Krstovski, Jelena Lazic, Goran Milosevic, Marianna Lucafò, Gabriele Stocco, Giuliana Decorti, Sonja Pavlovic and Nikola Kotur

to have aberrant expression or deregulation in diabetes ( 12 ), cancer ( 13 , 14 , 15 ) and other diseases. It has also been reported that ncRNAs are deregulated in leukemia ( 16 , 17 , 18 ). However, further inquiry into the role of ncRNAs in pediatric ALL is required. Growth arrest-specific 5 ( GAS5 ) is a long (more than 200 base pairs) non-coding RNA (lncRNA), which promotes apoptosis and halts the cell-cycle in T lymphocytes ( 8 ). Apart from its functional role as a growth arrest factor, GAS5 also imitates the glucocorticoid response element (GRE), a

Open access

Sabina Ngodigha, Roland Gbarabe and Ayeibatonworio Augustine

Abstract

A study of fishers’ knowledge in community based fisheries management practices in the Nun River estuary were conducted to assess the contribution of fishers’ knowledge to fisheries resources conservation. The total number of fishers that operated in the area were 390, and 221 fishers were interviewed based on a minimum of 10 years fishing experience using the socio-ecological approach. The laws introduced are banned on the use of mesh size less than five cm and banned on chemical fishing. Fishers caught using chemicals to fish were arrested and handed over to the police for prosecution. The management method has enhanced conservation of fisheries’ resources, which is a major source of livelihood for the people. It is therefore pertinent to introduce community based laws to check over exploitation of fisheries’ resources in fishing communities in the Niger Delta.

Open access

Sanja Mijatović, Milica Pešić, Marija Mojić, Jasna Banković, Đorde Miljković, Paolo Fagone, Katia Mangano, Ferdinando Nicoletti, James McCubrey, Nikola Tanić and Danijela Maksimović-Ivanić

, Baccarini S, et al. HIV protease inhibitors are potent antiangiogenic molecules and promote regression of Kaposi sarcoma. Nat Med 2002; 3: 225-32. 5. Chow WA, Guo S, Valdes-Albini F. Nelfinavir induces liposarcoma apoptosis and cell cycle arrest by up-regulating sterol regulatory element binding protein-1. Anticancer Drug 2006; 17: 891-903. 6. Pajonk F, Himmelsbach J, Riess K, Sommer A, McBride WH. The human immunodeficiency virus (HIV)-1 protease inhibitor saquinavir inhibits proteasome function and causes apoptosis and radiosensitization

Open access

Roya Razavizadeh and Ali Ehsanpour

References Aebi H. 1984. Catalase in vitro. Methods Enzymol. 105: 121-126. Alia P. S. P., Pardha Saradhi P., Mohanty P. 1991. Proline enhances primary photochemical activities in isolated thylakoid membranes of Brassica juncea by arresting photoinhibitory damage. Biochem. Biophys. Res. Commun. 181: 1238-1244. Alscher R. G., Erturk N., Heath L. S. 2002. Role of superoxide dismutases in controlling oxidative stress in plants. J. Exp. Bot. 53

Open access

Agnieszka Kiełkowska

Abstract

The effects of various concentrations of sorbitol (100, 200 and 360 mM) and NaCl (100, 200 and 300 mM) on root meristem cells of in vitro-cultured Allium cepa L. were analyzed after 10 and 20 days. Both root meristem cell cross-section area and nuclear volume decreased under osmotic and salt stress. The osmotic component of applied stresses had a greater impact on cell shrinkage, while ionic stress perturbed cell functioning, resulting in cell cycle arrest and various aberrations, affecting nucleus integrity. A concentration of 300 mM of NaCl in the culture medium caused complete inhibition of mitotic activity in onion root tip cells after 20 days of exposure. Analysis of the action of iso-osmotic concentrations of NaCl (200 mM) and sorbitol (360 mM) showed stronger mitodepressive effects of salt stress in comparison to osmotic stress.

Open access

M. Dvořáková, I. Weingartová, J. Nevoral, D. Němeček and T. Krejčová

References Abe K, Kimura H (1996): The possible role of hydrogen sulfide as an endogenous neuromodulator. The Journal of Neuroscience, 16, 1066-1071. Amagase H (2006): Clarifying the real bioactive constituents of garlic. Journal of Nutrition, 136, 716-725. Antosiewicz J, Herman-Antosiewicz A, Marynowski SW, Singh SV (2006): c-Jun NH2-terminal kinase signaling axis regu - lates diallyl trisulfide-induced generation of reactive oxygen species and cell cycle arrest in human prostate cancer cells. Cancer Research

Open access

Hrvoje Lepeduš, Mario Jakopec, Jasenka Antunović Dunić, Goran Krizmanić, Sanida Osmanović and Vera Cesar

Abstract

Despite numerous data dealing with the biogenesis of photosynthetic membranes connected with specific functional alterations in higher plants this is still an insufficiently understood topic and is one of the most promising areas of research in plant biochemistry. The main goal of our study was to detect the impact of different temperatures on chlorophyll biosynthesis and the maximum quantum yield of PSII (Fv/Fm). Therefore, we investigated the greening processes in etiolated sunflower cotyledons (Helianthus annuus L.) grown at different temperatures (10, 20 and 30 °C) during 24 h. The dynamics of chlorophyll a and b (Chl a and Chl b) accumulation as well as photosystem II (PSII) effi ciency were observed. We also evaluated combined effects of different temperatures (20 and 30 °C) and short-term application of increased irradiation (800 μmol m-2 s-1) on effective quantum yield of PSII (ΔF/F’m) and non photochemical quenching (NPQ) in cotyledons with fully developed PSII. Our results showed reduced chlorophyll accumulation and the arrest of PSII assembly at 10 °C in comparison with 20 and 30 °C. Further, the increased irradiance induced equal down regulation of effective quantum yield of PSII at 20 and 30 °C, with significantly higher capability of heat dissipation at 30 °C.

Open access

Z. S. Bondarenko and O. I. Zinenko

Abstract

Capture-mark-recapture data was used to infer growth rates of the Nikolsky’s viper, Vipera berus nikolskii (Vedmederja, Grubant et Rudaeva, 1986), in the Eastern Ukraine. We have found that growth rate is negatively correlated with age. The difference in growth rates before maturation is not significant between different sexes. Growth rates decrease rapidly after maturation in males and females, however adult males retain significantly higher average growth rates. There is large dispersion of growth rates in the group of adult females, which is caused, probably, by alteration of complete arrest of growth in the years with reproduction and more intensive growth in the years without it. Asymptotic snout-ventral length estimated after Von Bertalanffy model was 680 mm in females and 630 mm in males. Females mature after fifth and males mature after fourth hibernation. The larger females in vipers can not be the result of higher growth rates in females, but are the outcome of a combination of other factors including different maturation time and size (older and being larger), and, perhaps, longer life span due to lower mortality. Growth rates of the Nikolsky’s viper in the nature are higher than in other species in the group of small Eurasian vipers.

Open access

Jerzy Kawiak

Summary

The life span of adult cells is restricted, becoming senescent and eventually undergoing apoptosis. Cells are replaced by new ones which originate from a population of stem cells. An example is provided by the hemopoietic system in the bone marrow. In an adult body, stem cells may be identified by markers present in both embryonic and tissue-specific stem cells. Oct3/4, CXCR4, Nanog, CD133 and CD34 are examples of such markers. The stem cells share several properties, such as they may: 1) replicate and give rise to new stem cells, 2) differentiate into heterogenous tissue and organ specific cells and, finally, 3) stem cells are self-protected against various toxic agents and radiation. In adult tissues, stem cells reside in specialized sites (niches), for example in the bone marrow, skin, digestive tract epithelium, and skeletal muscles. Stem cells residing in these stem cell niches are anchored there by chemokines and adhesion molecules. Stroma-Derived Factor-1 (SDF-1), α-chemokine and stem-cell expressed receptor CXCR4 play an important role in the retention of stem cells in such niches. Several stress factors may attenuate the SDF-1-CXCR4 axis in the bone marrow, which leads to the release of stem cells from their niches into circulation. Another important stem cell niche-anchoring mechanism is the interaction of Wnt (a ligand) with Frizzled LRP (receptor). The recently accumulated evidence suggests that malignancy arises from an arrest in maturation and mutation of stem cells. Cancer stem cells are responsible for tumor growth, its relapse and metastasis. The first direct evidence for the existence of cancer stem cells came from observations of acute myeloblastic leukemia. Currently, cell populations enriched for cancer stem cells have been isolated from several tumors. The cancer stem cells represent less than 1% of tumor cells in the mouse models.