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Environmentally persistent free radicals (EPFRs) are a class of long-lived environmental risk substances that exist in air fine particulate matter (PM2.5). In the present study, different sample pre-treatment conditions were optimized. The developed method was successfully used to determine the contamination levels of EPFRs in PM2.5collected from Zhengzhou in winter. The results will be useful for extensive research on the sources, concentrations, formation mechanisms, physical-chemical characteristics and biological toxicity of EPFRs in the atmosphere.Different sample pre-treatment conditions (extraction solvent, methods and temperatures) were optimized. A novel method of soaking ultrasonic-assisted solvent extraction with methanol as extraction solvent under low temperature followed by electron paramagnetic resonance detection for the determination of environmentally persistent free radicals (EPFRs) in PM2.5. The method will be useful for extensive research of EPFRs in the atmosphere.

China has the largest number of managed honey bee colonies globally, but there is currently no data on viral infection in diseased A. mellifera L. colonies in China. In particular, there is a lack of data on chronic bee paralysis virus (CBPV) in Chinese honey bee colonies. Consequently, the present study investigated the occurrence and frequency of several widespread honey bee viruses in diseased Chinese apiaries, and we used the reverse transcription-polymerase chain reaction (RT-PCR) assay. Described was the relationship between the presence of CBPV and diseased colonies (with at least one of the following symptoms: depopulation, paralysis, dark body colorings and hairless, or a mass of dead bees on the ground surrounding the beehives). Phylogenetic analyses of CBPV were employed. The prevalence of multiple infections of honey bee viruses in diseased Chinese apiaries was 100%, and the prevalence of infections with even five and six viruses were higher than expected. The incidence of CBPV in diseased colonies was significantly higher than that in apparently healthy colonies in Chinese A. mellifera aparies, and CBPV isolates from China can be separated into Chinese-Japanese clade 1 and 2. The results indicate that beekeeping in China may be threatened by colony decline due to the high prevalence of multiple viruses with CBPV.

Outcome studies of immediate implant-based breast reconstruction have focused largely on patient factors, whereas the relative impact of the surgeon as a contributing variable is not known. As the procedure requires collaboration of both a surgical oncologist and a plastic surgeon, the effect of the surgeon team interaction can have a significant impact on outcome. This study examines outcomes in implant-based breast reconstruction and the association with patient characteristics, surgeon, and surgeon team familiarity.

Spiral ganglion neurons (SGN) in the Phex Hyp-Dukmale mouse, a murine model of postnatal endolymphatic hydrops (ELH) undergo progressive deterioration reminiscent of human and other animal models of ELH with features suggesting apoptosis as an important mechanism.

ABSTRACTStreptococcus pneumoniaeis the most common pathogen associated with otitis media. To examine the role of Toll-like receptor 2 (TLR2) in host defense against Streptococcus pneumoniaeinfection in the middle ear, wild-type (WT; C57BL/6) and TLR2-deficient (TLR2−/−) mice were inoculated with Streptococcus pneumoniae(1 × 106CFU) through the tympanic membrane. Nineteen of 37 TLR2−/−mice showed bacteremia and died within 3 days after the challenge, compared to only 4 of 32 WT mice that died. Of those that survived, more severe hearing loss in the TLR2−/−mice than in the WT mice was indicated by an elevation in auditory-evoked brain stem response thresholds at 3 or 7 days postinoculation. The histological pathology was characterized by effusion and tissue damage in the middle ear, and in the TLR2−/−mice, the outcome of infection became more severe at 7 days. At both 3 and 7 days postchallenge, the TLR2−/−mice had higher blood bacterial titers than the WT mice (P< 0.05), and typical bacteria were identified in the effusion from both ears of both mouse groups by acridine orange staining. Moreover, by 3 days postchallenge, the mRNA accumulation levels of NF-κB, tumor necrosis factor alpha, interleukin 1β, MIP1α, Muc5ac, and Muc5b were significantly lower in the ears of TLR2−/−mice than in WT mice. In summary, TLR2−/−mice may produce relatively low levels of proinflammatory cytokines following pneumococcal challenge, thus hindering the clearance of bacteria from the middle ear and leading to sepsis and a high mortality rate. This study provides evidence that TLR2 is important in the molecular pathogenesis and host response to otitis media.

Streptococcus pneumoniae is the most common pathogen associated with otitis media. To examine the role of Toll-like receptor 2 (TLR2) in host defense against Streptococcus pneumoniae infection in the middle ear, wild-type (WT; C57BL/6) and TLR2-deficient (TLR2–/–) mice were inoculated with Streptococcus pneumoniae (1 x 106CFU) through the tympanic membrane. Nineteen of 37 TLR2–/–mice showed bacteremia and died within 3 days after the challenge, compared to only 4 of 32 WT mice that died. Of those that survived, more severe hearing loss in the TLR2–/–mice than in the WT mice was indicated by an elevation in auditory-evoked brain stem response thresholds at 3 or 7 days postinoculation. The histological pathology was characterized by effusion and tissue damage in the middle ear, and in the TLR2–/–mice, the outcome of infection became more severe at 7 days. At both 3 and 7 days postchallenge, the TLR2–/–mice had higher blood bacterial titers than the WT mice (P < 0.05), and typical bacteria were identified in the effusion from both ears of both mouse groups by acridine orange staining. Moreover, by 3 days postchallenge, the mRNA accumulation levels of NF-B, tumor necrosis factor alpha, interleukin 1β, MIP1, Muc5ac, and Muc5b were significantly lower in the ears of TLR2–/–mice than in WT mice. In summary, TLR2–/–mice may produce relatively low levels of proinflammatory cytokines following pneumococcal challenge, thus hindering the clearance of bacteria from the middle ear and leading to sepsis and a high mortality rate. This study provides evidence that TLR2 is important in the molecular pathogenesis and host response to otitis media.

Vestibular evoked myogenic potentials (VEMPs) have been recorded from the neck musculature and the cervical spinal cord in humans and a limited number of laboratory animals in response to loud sound. However, the mouse VEMP has yet to be described. Evaluation of the sacculocollic pathway via VEMPs in mice can set the stage for future evaluations of mutant mice that now play an important role in research regarding human auditory and vestibular dysfunction.

A missense mutation in the mouse Col2a1gene has been discovered, resulting in a mouse phenotype with similarities to human spondyloepiphyseal dysplasia (SED) congenita. In addition, SED patients have been identified with a similar molecular mutation in human COL2A1. This mouse model offers a useful tool for molecular and biological studies of bone development and pathology.

In this paper, hex-pod-like Cu 2 O whiskers were successfully synthesized from a Cu(CH 3 COO) 2 precursor under hydrothermal conditions, and examined by means of scanning electron microscopy, X-ray microprobe analysis, and X-ray diffraction. The effects of precursor concentration and pH, reaction temperature and time on the evolution of Cu 2 O synthesis and morphology were investigated. The whiskers were composed of a nucleus and six pods. The pods grow along the 〈0 0 1〉 directions, and are bounded to {0 0 1} faces. The adjacent pods are perpendicular to each other. The dipolar characteristics of the Cu 2 O {0 0 1} faces are the critical factors in the synthesis of the peculiar Cu 2 O whiskers. Finally, a possible growth mechanism is proposed.

This paper presents a wireless, passive, remote query CO₂ sensor comprising a ribbon-like magnetoelastic thick-film coated with a mass-changing CO₂ responsive polymer synthesized from acrylamide and isooctylacrylate. In response to a magnetic field impulse, the magnetostrictive magnetoelastic sensor vibrates at a characteristic resonant frequency that is inversely dependent upon the mass of the attached CO₂ responsive polymer. The mechanical vibrations of the magnetostrictive sensor launch magnetic flux, which can be detected remotely using a pickup coil. By monitoring the resonant frequency of the passive sensor, the atmospheric CO₂ concentration can be determined without the need for physical connections to the sensor or specific alignment requirements. The effect of humidity and the CO₂ responsive copolymer composition on the measurement sensitivity are reported. Greatest sensitivity is achieved with a polymer comprising a 1 ∶ 1 mole ratio of acrylamide to isooctyl acrylate. A 0.7% change in atmospheric CO₂ concentration can be detected for a 20 µm thick polymer coated sensor.

Rat DNaseY band its human homolog DHP2 are members of a new family of DNaseI‐like endonucleases. They contain all the conserved amino acid residues to engage a DNaseI‐like catalytic activity and the same molecular mechanisms of DNA hydrolysis. The sequence similarity can be extended to other families of nucleases, such as FEN‐1, DNA polymerases, RNaseH and exonuclease III, involved in the ion‐dependent hydrolysis of nucleic acids. Their unique features include the NLS signals that place them in the nucleic and a high content of positively charged amino acid residues that results in their high affinity for the substrate. Their properties are consistent with a role in the early stage DNA degradation during apoptosis. The caspase‐DFF45/CIDE‐CPAN pathway is most likely involved in the second stage of internucleosomal DNA degradation. However, cells express constitutively multiple transcripts encoding DNA degrading enzymes and related molecules, hence they have the molecular diversity to engage the self‐destructive pathway appropriate to a given trigger.

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