First description of a fossil chamaeleonid from Greece and its relevance for the European biogeographic history of the group

The fossil record of Chamaeleonidae is very scarce and any new specimen is therefore considered important for our understanding of the evolutionary and biogeographic history of the group. New specimens from the early Miocene of Aliveri (Evia Island), Greece constitute the only fossils of these lizards from southeastern Europe. Skull roofing material is tentatively attributed to the Czech species Chamaeleo cf. andrusovi, revealing a range extension for this taxon, whereas tooth-bearing elements are described as indeterminate chamaeleonids. The Aliveri fossils rank well among the oldest known reptiles from Greece, provide evidence for the dispersal routes of chameleons out of Africa towards the European continent and, additionally, imply strong affinities with coeval chamaeleonids from Central Europe

Orbital interactions and chemical reactivity of metal particles and metal surfaces

A review is presented with 101 refs. on chem. bonding to metal surfaces and small metal particles demonstrating the power of symmetry concepts to predict changes in chem. bonding. Ab-initio calcns. of chemisorption to small particles, as well as semiempirical extended Hueckel calcns. applied to the study of the reactivity of metal slabs are reviewed. On small metal particles, classical notions of electron promotion and hybridization are found to apply. The surroundings of a metal atom (ligands in complexes, other metal atoms at surfaces), affect bonding and reactivity through the prehybridization they induce. A factor specific for large particles and surfaces is the required localization of electrons on the atoms involved in the metal surface bond. At the surface, the bond energy is found to relate to the grou8p orbital local d. of states at the Fermi level. The use of this concept is extensively discussed and illustrated for chemisorption of CO and dissocn. of NO on metal surfaces. A discussion is given of the current decompn. schemes of bond energies and related concepts (exchange (Pauli)-repulsion, polarization, charge transfer). The role of non-orthogonality of fragment orbitals and of kinetic and potential energy for Pauli repulsion and (orbital) polarization is analyzed. Numerous examples are discussed to demonstrate the impact of those concepts on chem. bonding theor

Social and Structural Factors Associated with HIV Infection among Female Sex Workers Who Inject Drugs in the Mexico-US Border Region

BACKGROUND: FSWs who inject drugs (FSW-IDUs) can acquire HIV through high risk sexual and injection behaviors. We studied correlates of HIV infection among FSW-IDUs in northern Mexico, where sex work is quasi-legal and syringes can be legally obtained without a prescription. METHODS: FSW-IDUs>18 years old who reported injecting drugs and recent unprotected sex with clients in Tijuana and Ciudad Juarez underwent surveys and HIV/STI testing. Logistic regression identified correlates of HIV infection. RESULTS: Of 620 FSW-IDUs, prevalence of HIV, gonorrhea, Chlamydia, trichomonas, syphilis titers ≥1:8, or any of these infections was 5.3%, 4%, 13%, 35%, 10% and 72%, respectively. Compared to other FSW-IDUs, HIV-positive women were more likely to: have syphilis titers ≥1:8 (36% vs. 9%, p<0.001), often/always inject drugs with clients (55% vs. 32%, p = 0.01), and experience confiscation of syringes by police (49% vs. 28%, p = 0.02). Factors independently associated with HIV infection were syphilis titers ≥1:8, often/always injecting with clients and police confiscation of syringes. Women who obtained syringes from NEPs (needle exchange programs) within the last month had lower odds of HIV infection associated with active syphilis, but among non-NEP attenders, the odds of HIV infection associated with active syphilis was significantly elevated. CONCLUSIONS: Factors operating in both the micro-social environment (i.e., injecting drugs with clients) and policy environment (i.e., having syringes confiscated by police, attending NEPs) predominated as factors associated with risk of HIV infection, rather than individual-level risk behaviors. Interventions should target unjustified policing practices, clients' risk behaviors and HIV/STI prevention through NEPs

A Strategy for the Proliferation of Ulva prolifera, Main Causative Species of Green Tides, with Formation of Sporangia by Fragmentation

Ulva prolifera, a common green seaweed, is one of the causative species of green tides that occurred frequently along the shores of Qingdao in 2008 and had detrimental effects on the preparations for the 2008 Beijing Olympic Games sailing competition, since more than 30 percent of the area of the games was invaded. In view of the rapid accumulation of the vast biomass of floating U. prolifera in green tides, we investigated the formation of sporangia in disks of different diameters excised from U. prolifera, changes of the photosynthetic properties of cells during sporangia formation, and development of spores. The results suggested that disks less than 1.00 mm in diameter were optimal for the formation of sporangia, but there was a small amount of spore release in these. The highest percentage of area of spore release occurred in disks that were 2.50 mm in diameter. In contrast, sporangia were formed only at the cut edges of larger disks (3.00 mm, 3.50 mm, and 4.00 mm in diameter). Additionally, the majority of spores liberated from the disks appeared vigorous and developed successfully into new individuals. These results implied that fragments of the appropriate size from the U. prolifera thalli broken by a variety of factors via producing spores gave rise to the rapid proliferation of the seaweed under field conditions, which may be one of the most important factors to the rapid accumulation of the vast biomass of U. prolifera in the green tide that occurred in Qingdao, 2008

Coronavirus Papain-like Proteases Negatively Regulate Antiviral Innate Immune Response through Disruption of STING-Mediated Signaling

Viruses have evolved elaborate mechanisms to evade or inactivate the complex system of sensors and signaling molecules that make up the host innate immune response. Here we show that human coronavirus (HCoV) NL63 and severe acute respiratory syndrome (SARS) CoV papain-like proteases (PLP) antagonize innate immune signaling mediated by STING (stimulator of interferon genes, also known as MITA/ERIS/MYPS). STING resides in the endoplasmic reticulum and upon activation, forms dimers which assemble with MAVS, TBK-1 and IKKε, leading to IRF-3 activation and subsequent induction of interferon (IFN). We found that expression of the membrane anchored PLP domain from human HCoV-NL63 (PLP2-TM) or SARS-CoV (PLpro-TM) inhibits STING-mediated activation of IRF-3 nuclear translocation and induction of IRF-3 dependent promoters. Both catalytically active and inactive forms of CoV PLPs co-immunoprecipitated with STING, and viral replicase proteins co-localize with STING in HCoV-NL63-infected cells. Ectopic expression of catalytically active PLP2-TM blocks STING dimer formation and negatively regulates assembly of STING-MAVS-TBK1/IKKε complexes required for activation of IRF-3. STING dimerization was also substantially reduced in cells infected with SARS-CoV. Furthermore, the level of ubiquitinated forms of STING, RIG-I, TBK1 and IRF-3 are reduced in cells expressing wild type or catalytic mutants of PLP2-TM, likely contributing to disruption of signaling required for IFN induction. These results describe a new mechanism used by CoVs in which CoV PLPs negatively regulate antiviral defenses by disrupting the STING-mediated IFN induction

Personal genome testing: Test characteristics to clarify the discourse on ethical, legal and societal issues

Background: As genetics technology proceeds, practices of genetic testing have become more heterogeneous: many different types of tests are finding their way to the public in different settings and for a variety of purposes. This diversification is relevant to the discourse on ethical, legal and societal issues (ELSI) surrounding genetic testing, which must evolve to encompass these differences. One important development is the rise of personal genome testing on the basis of genetic profiling: the testing of multiple genetic variants simultaneously for the prediction of common multifactorial diseases. Currently, an increasing number of companies are offering personal genome tests directly to consumers and are spurring ELSI-discussions, which stand in need of clarification. This paper presents a systematic approach to the ELSI-evaluation of personal genome testing for multifactorial diseases along the lines of its test characteristics. Discussion: This paper addresses four test characteristics of personal genome testing: its being a non-targeted type of testing, its high analytical validity, low clinical validity and problematic clinical utility. These characteristics raise their own specific ELSI, for example: non-targeted genetic profiling poses serious problems for information provision and informed consent. Questions about the quantity and quality of the necessary information, as well as about moral responsibilities with regard to the provision of information are therefore becoming central themes within ELSI-discussions of personal genome testing. Further, the current low level of clinical validity of genetic profiles raises questions concerning societal risks and regulatory requirements, whereas simultaneously it causes traditional ELSI-issues of clinical genetics, such as psychological and health risks, discrimination, and stigmatization, to lose part of their relevance. Also, classic notions of clinical utility are challenged by the newer notion of 'personal utility.' Summary: Consideration of test characteristics is essential to any valuable discourse on the ELSI of personal genome testing for multifactorial diseases. Four key characteristics of the test - targeted/non-targeted testing, analytical validity, clinical validity and clinical utility - together determine the applicability and the relevance of ELSI to specific tests. The paper identifies and discusses four areas of interest for the ELSI-debate on personal genome testing: informational problems, risks, regulatory issues, and the notion of personal utility