Abstract. From 2006 to 2007, the daily concentrations of major inorganic water-soluble constituents, mineral aerosol, organic carbon (OC) and elemental carbon (EC) in ambient PM 10 samples were investigated from 16 urban, rural and remote sites in various regions of China, and were compared with global aerosol measurements. A large difference between urban and rural chemical species was found, normally with 1.5 to 2.5 factors higher in urban than in rural sites. Optically-scattering aerosols, such as sulfate (∼16 %), OC (∼15 %), nitrate (∼7 %), ammonium (∼5 %) and mineral aerosol (∼35 %) in most circumstance, are majorities of the total aerosols, indicating a dominant scattering feature of aerosols in China. Of the total OC, ∼55 %-60 % can be attributed to the formation of the secondary organic carbon (SOC). The absorbing aerosol EC only accounts for ∼3.5 % of the total PM 10 . Seasonally, maximum concentrations of most aerosol species were found in winter while mineral aerosol peaks in spring. In addition to the regular seasonal maximum, secondary peaks were found for sulfate and ammonium in summer and for OC and EC

During 2006 and 2007, the daily concentrations of major water-soluble constituents, mineral aerosol, organic carbon (OC) and elemental carbon (EC) in ambient PM₁₀ samples were investigated from 16 urban, rural and remote sites in various regions of China, and were compared with global aerosol. A large difference between urban and rural chemical species was found, normally with 1.5 to 2.5 factors higher in urban than in rural sites. Optically-scattering aerosols such as sulfate (~16%), OC (~15%), nitrate (~7%) and ammonium (~5%) consist of ~50% of the total aerosols with another ~35% from mineral aerosol also having a certain degree of scattering ability, indicating a dominant scattering feature of aerosols in China. Of the total OC, ~55%–60% can be attributed to the secondary organic carbon (SOC). The absorbing aerosol EC accounts for ~3.5% of the total PM₁₀. Seasonally, maximum concentrations of most aerosol species are found in winter while mineral aerosol also peaks in spring. Second peaks were found for sulfate and ammonium in summer and for OC and EC in May and June. This can be considered as a typical seasonal pattern in various aerosol components in China. Aerosol acidity is normally neutral in most of urban areas, but becomes somewhat acidic in rural areas. Based on the surface visibility from 681 meteorological stations in China during 1957–2005, four major haze areas are also identified with similar visibility changes, namely, (1) Hua Bei Plain in N. China, plus the Guanzhong Plain; (2) E. China with the main body in the Yangtze River Delta area; (3) S. China with most areas of Guangdong and the Pearl River Delta area; (4) The Si Chuan Basin in S. W. China. The degradation of visibility in these areas is linked with the emission changes and high PM concentrations. Such quantitative chemical characterization of aerosols is essential in assessing their role in atmospheric chemistry and weather-climate effects, and in validating atmospheric models

The membrane protein CD36 has been reported to carry out a wide range of potential functions, including serving as a receptor for thrombospondin, collagen, oxidized low density lipoprotein, fatty acids, anionic phospholipids, and Plasmodium falciparum malaria parasitized erythrocytes. This implicates CD36 in cellular adhesion, human atherosclerotic lesion formation, lipid metabolism, and malaria. A presumed rat homolog of CD36 was previously reported to be palmitoylated. We confirmed that human CD36 is palmitoylated and identified cysteines 3, 7, 464, and 466 as the palmitoylation sites using a mutagenesis approach. This result suggests that both the N- and C-terminal tails of CD36 are cytoplasmic. Published models for the topology of CD36 have the C terminus located in the cytoplasm but differ as to whether the N terminus is cytoplasmic or extracellular. To address this question, a C-terminal truncation mutant of CD36 was made by introducing a stop codon just upstream of the C-terminal transmembrane domain. This mutant was found membrane-bound when expressed in human embryonic kidney 293 cells, indicating that the N-terminal hydrophobic domain serves as a transmembrane anchor, and thus supporting a CD36 topology with two transmembrane domains.

Regimen adherence remains a major hurdle to the success of daily oral drug regimens for the treatment and prevention of human immunodeficiency virus (HIV) infection. Long-acting drug formulations requiring less-frequent dosing offer an opportunity to improve adherence and allow for more forgiving options with regard to missed doses. The administration of long-acting formulations in a clinical setting enables health care providers to directly track adherence. MK-8591 (4'-ethynyl-2-fluoro-2'-deoxyadenosine [EFdA]) is an investigational nucleoside reverse transcriptase translocation inhibitor (NRTTI) drug candidate under investigation as part of a regimen for HIV treatment, with potential utility as a single agent for preexposure prophylaxis (PrEP). The active triphosphate of MK-8591 (MK-8591-TP) exhibits protracted intracellular persistence and, together with the potency of MK-8591, supports its consideration for extended-duration dosing. Toward this end, drug-eluting implant devices were designed to provide prolonged MK-8591 release and Implants, administered subcutaneously, were studied in rodents and nonhuman primates to establish MK-8591 pharmacokinetics and intracellular levels of MK-8591-TP. These data were evaluated against pharmacokinetic and pharmacodynamic models, as well as data generated in phase 1a (Ph1a) and Ph1b clinical studies with once-weekly oral administration of MK-8591. After a single administration in animals, MK-8591 implants achieved clinically relevant drug exposures and sustained drug release, with plasma levels maintained for greater than 6 months that correspond to efficacious MK-8591-TP levels, resulting in a 1.6-log reduction in viral load. Additional studies of MK-8591 implants for HIV treatment and prevention are warranted.

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