http://www.mdpi.com/journal/molecules/special_issues/selenium-tellurium-chemistry/ Submission All papers should be submitted to molecules@mdpi.org with copy to the guest editor. To be published continuously until the deadline and papers will be listed together at the special websites. Submitted papers should not have been previously published nor be currently under consideration for publication elsewhere. All papers are refereed through a peer review process. A guide for authors, sample copies and other relevant information for submitting papers are available on the Instructions for Authors page. Molecules is an international peer-reviewed monthly journal published by Molecular Diversity Preservation International. Please visit the Instructions for Authors page before submitting a paper. Open Access publication fees are 800 CHF per paper. English correction fees (250 CHF) will be added in certain cases (1050 CHF per paper for those papers that require extensive additional formatting and/or English corrections.). http://www.mdpi.com/1420-3049/14/12/4880/ The diversity of selenoproteins raises the question of why so many life forms require selenium. Selenoproteins are found in bacteria, archaea, and many eukaryotes. In photosynthetic microorganisms, the essential requirement for selenium has been reported in 33 species belonging to six phyla, although its biochemical significance is still unclear. According to genome databases, 20 species are defined as selenoprotein-producing organisms, including five photosynthetic organisms. In a marine coccolithophorid, Emiliania huxleyi (Haptophyta), we recently found unique characteristics of selenium utilization and novel selenoproteins using 75Se-tracer experiments. In E. huxleyi, selenite, not selenate, is the main substrate used and its uptake is driven by an ATP-dependent highaffinity, active transport system. Selenite is immediately metabolized to low-molecular mass compounds and partly converted to at least six selenoproteins, named EhSEP1–6. The most (EhSEP2) and second-most abundant selenoproteins (EhSEP1) are disulfide isomerase (PDI) homologous protein and thioredoxin reductase (TR) 1, respectively. Involvement of selenium in PDI is unique in this organism, while TR1 is also found in other organisms. In this review, we summarize physiological, biochemical, and molecular aspects of selenium utilization by microalgae and discuss their strategy of selenium utilization. http://www.mdpi.com/1420-3049/14/12/4880/ Mon, 30 Nov 2009 00:00:00 CET Molecules 2009-11-30 14 12 Review 4880 4891 1420-3049 Selenium Utilization Strategy by Microalgae 2009-11-30 doi: 10.3390/molecules14124880 Hiroya Araie Yoshihiro Shiraiwa http://www.mdpi.com/1420-3049/14/11/4440/ The amounts of selenium (Se), iron (Fe), and zinc (Zn) in the liver, kidney, and spleen as a function of age of rats measured using instrumental neutron activation analysis were compared between Se-deficient (SeD) rats and normal rats. The SeD model rats can live for more than 50 weeks. The effect of Se-deficinecy in rats might be weak, compared to the marked malfunction of GSH-Px. The SeD rats can be considered as a model of nonlethal chronic oxidative stress. Fluctuations of Fe and Zn in the liver of Se-deficient rats were observed. The amount of redox-relating minerals, such as Fe and Zn, in SeD rat organs is changeable depending on the age. http://www.mdpi.com/1420-3049/14/11/4440/ Thu, 05 Nov 2009 00:00:00 CET Molecules 2009-11-05 14 11 Article 4440 4453 1420-3049 The Effect of Long-Running Severe Selenium-Deficiency on the Amount of Iron and Zinc in the Organs of Rats 2009-11-05 doi: 10.3390/molecules14114440 Ken-ichiro Matsumoto Sachiyo Terada Marie Ariyoshi Aya Okajo Atsushi Hisamatsu Iori Ui Kazutoyo Endo http://www.mdpi.com/1420-3049/14/11/4337/ Despite being close neighbors on the Periodic Table, selenium and tellurium present a totally different abilities to form glasses. Se is a very good glass former, and gives rise to numerous glass compositions which are popular for their transparency in the infrared range and their stability against crystallization. These glasses can be shaped into sophisticated optical devices such as optical fibers, planar guides or lenses. Nevertheless, their transparencies are limited at about 12 μm (depending on the thickness of the optical systems) due to the relatively small mass of the Se element. On the other hand, tellurium is heavier and its use in substitution for Se permits to shift the IR cutoff beyond 20 μm. However, the semimetallic nature of Te limits its glass formation ability and this glass family is known to be unstable and consequently has found application as phase change material in the Digital Versatile Disk (DVD) technology. In this paper, after a review of selenide glasses and their applications, it will be shown how, in a recent past, it has been possible to stabilize tellurium glasses by introducing new elements like Ga or I in their compositions. http://www.mdpi.com/1420-3049/14/11/4337/ Mon, 26 Oct 2009 00:00:00 CET Molecules 2009-10-26 14 11 Review 4337 4350 1420-3049 Forming Glasses from Se and Te 2009-10-26 doi: 10.3390/molecules14114337 Bruno Bureau Catherine Boussard-Pledel Pierre Lucas Xianghua Zhang Jacques Lucas http://www.mdpi.com/1420-3049/14/10/3975/ The essential trace element selenium, which is a crucial cofactor in the most important endogenous antioxidative systems of the human body, is attracting more and more the attention of both laypersons and expert groups. The interest of oncologists mainly focuses in the following clinical aspects: radioprotection of normal tissues, radiosensitizing in malignant tumors, antiedematous effect, prognostic impact of selenium, and effects in primary and secondary cancer prevention. Selenium is a constituent of the small group of selenocysteine-containing selenoproteins and elicits important structural and enzymatic functions. Selenium deficiency has been linked to increased infection risk and adverse mood states. It has been shown to possess cancer-preventive and cytoprotective activities in both animal models and humans. It is well established that Se has a key role in redox regulation and antioxidant function, and hence in membrane integrity, energy metabolism and protection against DNA damage. Recent clinical trials have shown the importance of selenium in clinical oncology. Our own clinical study involving 48 patients suggest that selenium has a positive effect on radiation-associated secondary lymphedema in patients with limb edemas, as well as in the head and neck region, including endolaryngeal edema. Another randomized phase III study of our group was performed to examine the cytoprotective properties of selenium in radiation oncology. The aim was to evaluate whether sodium selenite is able to compensate a preexisting selenium deficiency and to prevent radiation induced diarrhea in adjuvant radiotherapy for pelvic gynecologic malignancies. Through this study, the significant benefits of sodium selenite supplementation with regards to selenium deficiency and radiotherapy induced diarrhea in patients with cervical and uterine cancer has been shown for the first time in a prospective randomized trial. Survival data imply that supplementation with selenium does not interfere with the positive biological effects of radiation treatment and might constitute a valuable adjuvant therapy option especially in marginally supplied individuals. More recently there were emerging concerns coming up from two large clinical prevention trials (NPC, SELECT), that selenium increases the possible risk of developing diabetes type II. Despite obvious flaws of both studies and good counterarguments, a controversial debate remains on the possible advantage and risks of selenium in cancer prevention. However, in the light of the recent clinical trials the potential benefits of selenium supplementation in tumor patients are undeniable, even if further research is needed. http://www.mdpi.com/1420-3049/14/10/3975/ Mon, 12 Oct 2009 00:00:00 CEST Molecules 2009-10-12 14 10 Review 3975 3988 1420-3049 Selenium in Oncology: From Chemistry to Clinics 2009-10-12 doi: 10.3390/molecules14103975 Oliver Micke Lutz Schomburg Jens Buentzel Klaus Kisters Ralph Muecke http://www.mdpi.com/1420-3049/14/9/3567/ The chemistry of the M (M=Fe, Ca, Ba)-Se-H2O systems at 25 °C is reviewed based on our previous papers. In this paper, the phase equilibria in the Fe(III)-Se(IV)-H2O, Ca-Se(IV,VI)-H2O and Ba-Se(IV,VI)-H2O systems at 25 °C are discussed. Then, the three-stage process for removal of selenium from industrial waste water [Se(IV,VI) < 1,500 mg/L] containing sulfuric acid was introduced. This seems to be a promising process for selenium removal from acidic sulfate waste water containing high concentration levels of selenium to below 0.1 mg/L. http://www.mdpi.com/1420-3049/14/9/3567/ Mon, 14 Sep 2009 00:00:00 CEST Molecules 2009-09-14 14 9 Review 3567 3588 1420-3049 Chemistry of the M (M=Fe, Ca, Ba)-Se-H2O Systems at 25 °C 2009-09-14 doi: 10.3390/molecules14093567 Tadahisa Nishimura Ryosuke Hata Fumihiko Hasegawa http://www.mdpi.com/1420-3049/14/9/3509/ Selenium (Se) deficiency has been known for many years to be associated with disease, impaired growth and a variety of other metabolic disorders in mammals. Only recently has the major role that Se-containing proteins, designated selenoproteins, play in many aspects of health and development begun to emerge. Se is incorporated into protein by way of the Se-containing amino acid, selenocysteine (Sec). The synthesis of selenoproteins is dependent on Sec tRNA for insertion of Sec, the 21st amino acid in the genetic code, into protein. We have taken advantage of this dependency to modulate the expression of Sec tRNA that in turn modulates the expression of selenoproteins by generating transgenic, conditional knockout, transgenic/standard knockout and transgenic/conditional knockout mouse models, all of which involve the Sec tRNA gene, to elucidate the intracellular roles of this protein class. http://www.mdpi.com/1420-3049/14/9/3509/ Thu, 10 Sep 2009 00:00:00 CEST Molecules 2009-09-10 14 9 Review 3509 3527 1420-3049 Mouse Models Targeting Selenocysteine tRNA Expression for Elucidating the Role of Selenoproteins in Health and Development 2009-09-10 doi: 10.3390/molecules14093509 Bradley A. Carlson Min-Hyuk Yoo Petra A. Tsuji Vadim N. Gladyshev Dolph L. Hatfield http://www.mdpi.com/1420-3049/14/9/3367/ It was found that cesium carbonate has a unique catalytic ability on the reaction of carbonyl compounds with diphenyl diselenide to give the corresponding α-phenylseleno carbonyl compounds in moderate to good yields. Similarly, the α-phenylthiolation of carbonyl compounds with diphenyl disulfide was promoted by the cesium carbonate catalyst. http://www.mdpi.com/1420-3049/14/9/3367/ Wed, 02 Sep 2009 00:00:00 CEST Molecules 2009-09-02 14 9 Communication 3367 3375 1420-3049 Cesium Carbonate-Catalyzed α-Phenylchalcogenation of Carbonyl Compounds with Diphenyl Dichalcogenide 2009-09-02 doi: 10.3390/molecules14093367 Yutaka Nishiyama Yuya Koguma Toshimasa Tanaka Rui Umeda http://www.mdpi.com/1420-3049/14/9/3313/ The synthesis and cytotoxic activity of a series of twenty six aroyl and heteroaroyl selenylacetic acid derivatives of general formula Ar-CO-Se-CH2-COOH or Heterar-CO-Se-CH2-COOH are reported. The synthesis was carried out by reaction of acyl chlorides with sodium hydrogen selenide, prepared in situ, and this led to the formation of sodium aroylselenides that subsequently reacted with α-bromoacetic acid to produce the corresponding selenylacetic acid derivatives. All of the compounds were tested against a prostate cancer cell line (PC-3) and some of the more active compounds were assessed against a panel of four human cancer cell lines (CCRF-CEM, HTB-54, HT-29, MCF-7) and one mammary gland-derived non-malignant cell line (184B5). Some of the compounds exhibited remarkable cytotoxic and antiproliferative activities against MCF-7 and PC-3 that were higher than those of the reference compounds doxorubicin and etoposide, respectively. For example, in MCF-7 when Ar = phenyl, 3,5-dimethoxyphenyl or benzyl the TGI values were 3.69, 4.18 and 6.19 μM. On the other hand, in PC-3 these compounds showed values of 6.8, 4.0 and 2.9 μM. Furthermore, benzoylselenylacetic acid did not provoke apoptosis nor did it perturb the cell cycle in MCF-7. http://www.mdpi.com/1420-3049/14/9/3313/ Tue, 01 Sep 2009 00:00:00 CEST Molecules 2009-09-01 14 9 Article 3313 3338 1420-3049 Synthesis and Pharmacological Screening of Several Aroyl and Heteroaroyl Selenylacetic Acid Derivatives as Cytotoxic and Antiproliferative Agents 2009-09-01 doi: 10.3390/molecules14093313 Carmen Sanmartín Daniel Plano Enrique Domínguez María Font Alfonso Calvo Celia Prior Ignacio Encío Juan Antonio Palop http://www.mdpi.com/1420-3049/14/9/3229/ Density-functional theory is used to model the endo and exo transition states for [2,3]-sigmatropic rearrangement of allylic aryl-selenoxides and -selenimides. The endo transition state is generally preferred for selenoxides if there is no substitution at the 2 position of the allyl group. Based upon the relative energies of the endo and exo transition states, enantioselectivity of rearrangements is expected to be greatest for molecules with substitutions at the 1- or (E)-3- position of the allyl group. Ortho substitution of a nitro group on the ancillary selenoxide phenyl ring reduces the activation barriers, increases the difference between the endo and exo activation barriers and shifts the equilibrium toward products. http://www.mdpi.com/1420-3049/14/9/3229/ Fri, 28 Aug 2009 00:00:00 CEST Molecules 2009-08-28 14 9 Article 3229 3236 1420-3049 Theoretical Studies of [2,3]-Sigmatropic Rearrangements of Allylic Selenoxides and Selenimides 2009-08-28 doi: 10.3390/molecules14093229 Craig A. Bayse Sonia Antony http://www.mdpi.com/1420-3049/14/9/3115/ A large variety of different interactions between the chalcogen atoms, Q, occur in the solid state structures of polyselenides and polytellurides, including both molecular and infinite units. The simplest motifs are classical Q22– dumbbells and nonlinear Qn2– chains (n = 3, 4, 5, ..), e.g. found in alkali metal polychalcogenides. In addition, nonclassical so-called hypervalent motifs exist in the form of linear Q34– units or within larger units such as Q44– and Q54–. Infinitely extended Q units include zigzag, cis/trans and linear chains, as well as planar and slightly puckered layers. Several of those are susceptible to Peierls distortions, leading to the formation of both commensurate and incommensurate superstructures and anomalies in transport properties, including metal-nonmetal transitions. http://www.mdpi.com/1420-3049/14/9/3115/ Mon, 24 Aug 2009 00:00:00 CEST Molecules 2009-08-24 14 9 Review 3115 3131 1420-3049 Solid State Polyselenides and Polytellurides: A Large Variety of Se–Se and Te–Te Interactions 2009-08-24 doi: 10.3390/molecules14093115 Christian Graf Abdeljalil Assoud Oottil Mayasree Holger Kleinke http://www.mdpi.com/1420-3049/14/7/2555/ A series of aromatic diacyl tellurides were prepared in moderate to good yields by the reactions of sodium orpotassium arenecarbotelluroates with acyl chlorides in acetonitrile. X-ray structure analyses and theoretical calculations of 2-methoxybenzoic anhydride and bis(2-methoxybenzoyl) sulfide, selenide and telluride were carried out. The two 2-MeOC6H4CO moieties of bis(2-methoxybenzoyl) telluride are nearly planar and the two methoxy oxygen atoms intramolecularly coordinate to the central tellurium atom from both side of C(11)-Te(11)-C(22) plane. In contrast, the oxygen and sulfur isologues (2-MeOC6H4CO)2E (E = O, S), show that one of the two methoxy oxygen atoms contacts with the oxygen atom of the carbonyl group connected to the same benzene ring. The structure of di(2-methoxybenzoyl) selenide which was obtained by MO calculation resembles that of tellurium isologues rather than the corresponding oxygen and sulfur isologues. The reactions of di(aroyl) tellurides with Grignard reagents lead to the formation of tellurocarboxylato magnesium complexes [MgBr][R(C=Te)O]. http://www.mdpi.com/1420-3049/14/7/2555/ Mon, 13 Jul 2009 00:00:00 CEST Molecules 2009-07-13 14 7 Article 2555 2572 1420-3049 Diaroyl Tellurides: Synthesis, Structure and NBO Analysis of (2-MeOC6H4CO)2Te – Comparison with Its Sulfur and Selenium Isologues. The First Observation of [MgBr][R(C=Te)O] Salts 2009-07-13 doi: 10.3390/molecules14072555 Osamu Niyomura Shoho Nakaiida Ryo Yamada Shinzi Kato Masaru Ishida Masahiro Ebihara Fumio Ando Jugo Koketsu http://www.mdpi.com/1420-3049/14/7/2337/ Selenium is a chemical element participating in the synthesis of selenocysteine residues that play a pivotal role in the enzymatic activity efficiency of selenoproteines. The methionine sulfoxide reductase (Msr) system that reduces methionine sulfoxide (MetO) to methionine comprises the selenoprotein MsrB (MsrB1) and the non-selenoprotein MsrA, which reduce the R- and the S- forms of MetO, respectively. The effects of a selenium deficient (SD) diet, which was administrated to wild type (WT) and MsrA knockout mice (MsrA-/-), on the expression and function of Msr-related proteins are examined and discussed. Additionally, new data about the levels of selenium in brain, liver, and kidneys of WT and MsrA-/- mice are presented and discussed. http://www.mdpi.com/1420-3049/14/7/2337/ Wed, 01 Jul 2009 00:00:00 CEST Molecules 2009-07-01 14 7 Review 2337 2344 1420-3049 Selenium and the Methionine Sulfoxide Reductase System 2009-07-01 doi: 10.3390/molecules14072337 Derek B. Oien Jackob Moskovitz http://www.mdpi.com/1420-3049/14/3/1263/ Selenium is an essential trace element for humans and animals, and selenium deficiency is associated with several disease conditions such as immune impairment. In addition, selenium intakes that are greater than the recommended daily allowance (RDA) appear to protect against certain types of cancers. In humans and animals, cell proliferation and death must be regulated to maintain tissue homeostasis, and it has been well documented that numerous human diseases are directly related to the control of cell cycle progression and apoptosis. Thus, the elucidation of the mechanisms by which selenium regulates the cell cycle and apoptosis can lead to a better understanding of the nature of selenium’s essentiality and its role in disease prevention. This article reviews the status of knowledge concerning the effect of selenium on cell cycle and apoptosis http://www.mdpi.com/1420-3049/14/3/1263/ Mon, 23 Mar 2009 00:00:00 CET Molecules 2009-03-23 14 3 Review 1263 1278 1420-3049 Selenium as an Essential Micronutrient: Roles in Cell Cycle and Apoptosis 2009-03-23 doi: 10.3390/molecules14031263 Huawei Zeng http://www.mdpi.com/1420-3049/14/3/1111/ Laser radiation-induced decomposition of gaseous organic selenides and tellurides resulting in chemical deposition of nanostructured materials on cold surfaces is reviewed with regard to the mechanism of the gas-phase decomposition and properties of the deposited materials. The laser photolysis and laser thermolysis of the Se and Te precursors leading to chalcogen deposition can also serve as a useful approach to nanostructured chalcogen composites and IVA group (Si, Ge, Sn) element chalcogenides provided that it is carried out simultaneously with laser photolysis or thermolysis of polymer and IVA group element precursor. http://www.mdpi.com/1420-3049/14/3/1111/ Thu, 12 Mar 2009 00:00:00 CET Molecules 2009-03-12 14 3 Review 1111 1125 1420-3049 Laser Photolysis and Thermolysis of Organic Selenides and Tellurides for Chemical Gas-phase Deposition of Nanostructured Materials 2009-03-12 doi: 10.3390/molecules14031111 Josef Pola Akihiko Ouchi http://www.mdpi.com/1420-3049/14/3/904/ Complex formation of the glutathione peroxidase mimics 2,2¢-ditelluro-bridged b-cyclodextrin (1) and 2,2¢-diseleno-bridged b-cyclodextrin (2), with S-substituted dinitrophenyl glutathione (3) were determined by ultraviolet-visible (UV-Vis) absorption spectroscopy in phosphate buffer (pH 7.4) and 1H-NMR spectroscopy. Molecular mechanics (MM2) modeling calculations were used to deduce a three-dimensional model for each complex. The dinitrophenyl (DNP) group of 3 appears to penetrate the cavity of b-cyclodextrin (b-CD) or 1, but it is located between the two secondary rims of 2. The complexes’ stability constants (Ks) from 19 to 37 °C, Gibbs free energy changes (DG° ), DH° and TDS° for 1:1 complexes of b-CD, 1 and 2 with ligand 3 as obtained from UV-Vis spectra were compared. The binding of 3 by the three cyclodextrin hosts generally decreased in the order of 1>2>b-CD. The binding ability of 3 by b-CD, 1 and 2 was discussed with regard to the size/shape-fit concept, the induced-fit interaction, and the cooperative interaction of the dual hydrophobic cavities. The binding ability of 1>2indicated that the length of linkage between two cyclodextrin units plays a crucial role in the interaction with 3. http://www.mdpi.com/1420-3049/14/3/904/ Wed, 25 Feb 2009 00:00:00 CET Molecules 2009-02-25 14 3 Article 904 916 1420-3049 Association Mechanism of S-Dinitrophenyl Glutathione with Two Glutathione Peroxidase Mimics: 2, 2¢-Ditelluro- and 2, 2¢-Diseleno-bridged b-cyclodextrins 2009-02-25 doi: 10.3390/molecules14030904 Ya-Qiong Hao Xing-Chen Liu Jun-Qiu Liu Yu-Qing Wu http://www.mdpi.com/1420-3049/14/2/884/ The X-ray structures of 12 primary selenoamides are reported. Metric parameters are provided, together with an illustration of the range of hydrogen bonding motifs. http://www.mdpi.com/1420-3049/14/2/884/ Mon, 23 Feb 2009 00:00:00 CET Molecules 2009-02-23 14 2 Article 884 892 1420-3049 The X-Ray Crystal Structures of Primary Aryl Substituted Selenoamides 2009-02-23 doi: 10.3390/molecules14020884 Yang Li Guo-Xiong Hua Alexandra M. Z. Slawin J. Derek Woollins http://www.mdpi.com/1420-3049/14/1/141/ The purpose of this research was to investigate the relationship between selenium levels, thyroid function and other coronary risk factors in 140 Saudi subjects without overt coronary heart disease stratified by age. Demographic data and serum fasting lipid profile, glucose, thyroid function tests, selenium status and dietary intake was assessed. The relationships between selenium status, thyroid function and cardiovascular risk factors were assessed by univariate and multivariate analysis. The results showed that thyroid hormone levels did not differ with age. Erythrocyte glutathione peroxidase (GPx) levels were significantly higher in the youngest vs. oldest tertile (p<0.0001). Selenium and iodine intake did not differ significantly with age tertile, but the average intake for the population sample was below the estimated average requirements for both elements. Serum lipoprotein (a) concentrations correlated with selenium (r = 0.417, p<0.0001) and TSH (r = 0.172, p<0.05). After adjustment for confounding variables; serum fT4 and erythrocytes GPx remained significant determinants of serum TSH levels, whilst serum selenium and TSH were determinants of serum fT4 levels. Serum Lp(a), a coronary risk factor, was strongly related to measures of selenium status. A significant relationship between measures of selenium status and thyroid function was found. Serum Lp(a) a known risk factor for cardiovascular disease was also related to selenium status in our population. http://www.mdpi.com/1420-3049/14/1/141/ Wed, 31 Dec 2008 00:00:00 CET Molecules 2008-12-31 14 1 Article 141 159 1420-3049 Selenium Status and Cardiovascular Risk Profile in Healthy Adult Saudi Males 2008-12-31 doi: 10.3390/molecules14010141 Eman M. Alissa Waqar H. Ahmed Nabeel Al-ama Gordon A. A. Ferns