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Abstract Background Urban air pollution is an increasing health problem, particularly in Asia, where the combustion of fossil fuels has increased rapidly as a result of industrialization and socio-economic development. The adverse health impacts of urban air pollution are well established, but less is known about effective intervention strategies. In this demonstration study we set out to establish methods to assess whether wearing an R95 activated carbon respirator could reduce intake of polycyclic aromatic hydrocarbons (PAH) in street workers in Hanoi, Vietnam. Methods In this demonstration study we performed a cross-over study in which non-smoking participants that worked at least 4 hours per day on the street in Hanoi were randomly allocated to specific respirator wearing sequences for a duration of 2 weeks. Urines were collected after each period, i.e. twice per week, at the end of the working day to measure hydroxy PAHs (OH-PAH) using gas chromatography/high resolution mass spectrometry. The primary endpoint was the urinary concentration of 1-hydroxypyrene (1-OHP). Results Forty-four participants (54.5% male, median age 40 years) were enrolled with the majority being motorbike taxi drivers (38.6%) or street vendors (34.1%). The baseline creatinine corrected urinary level for 1-OHP was much higher than other international comparisons: 1020 ng/g creatinine (IQR: 604–1551). Wearing a R95 mask had no significant effect on 1-OHP levels: estimated multiplicative effect 1.0 (95% CI: 0.92-1.09) or other OH-PAHs, except 1-hydroxynaphthalene (1-OHN): 0.86 (95% CI: 0.11-0.96). Conclusions High levels of urine OH-PAHs were found in Hanoi street workers. No effect was seen on urine OH-PAH levels by wearing R95 particulate respirators in an area of high urban air pollution, except for 1-OHN. A lack of effect may be de to gaseous phase PAHs that were not filtered efficiently by the respirator. The high levels of urinary OH-PAHs found, urges for effective interventions. Trial registration ISRCTN74390617 (date of assignation: 04/08/2009).

Abstract Introduction Cochlear implants known to provide support in individuals with bilateral hearing loss may also be of great benefit for individuals with unilateral hearing loss. This case report demonstrates the positive effects of cochlear implantation on speech understanding in noise conditions in patients with unilateral hearing loss and normal hearing on the contralateral side. To the best of our knowledge, the data presented here are from the first few cases to receive a cochlear implant for unilateral hearing loss. Case presentation Four Caucasian German men, two aged 48 and the others aged 51 and 57 years old, with post-lingual unilateral hearing loss and normal hearing on the contralateral side were implanted with a cochlear implant. All our patients were members of the German army. Before and after implantation, they were given a battery of speech tests in different hearing conditions to assess the effect of unilateral cochlear implantation on speech understanding in noise conditions. Test results showed that all patients benefited from unilateral cochlear implantation, particularly in terms of speech understanding in noise conditions. Conclusions Unilateral cochlear implantation might be a successful treatment method for patients with unilateral hearing loss not benefiting from alternative treatment options. The results of this case report open up the field of cochlear implantation for expanded criteria and new areas of research.

Abstract Background Human T-lymphotropic virus type 1 (HTLV-1) is an important human retrovirus that is a cause of adult T-cell leukemia/lymphoma. While an important human pathogen, the details regarding virus replication cycle, including the nature of HTLV-1 particles, remain largely unknown due to the difficulties in propagating the virus in tissue culture. In this study, we created a codon-optimized HTLV-1 Gag fused to an EYFP reporter as a model system to quantitatively analyze HTLV-1 particles released from producer cells. Results The codon-optimized Gag led to a dramatic and highly robust level of Gag expression as well as virus-like particle (VLP) production. The robust level of particle production overcomes previous technical difficulties with authentic particles and allowed for detailed analysis of particle architecture using two novel methodologies. We quantitatively measured the diameter and morphology of HTLV-1 VLPs in their native, hydrated state using cryo-transmission electron microscopy (cryo-TEM). Furthermore, we were able to determine HTLV-1 Gag stoichiometry as well as particle size with the novel biophysical technique of fluorescence fluctuation spectroscopy (FFS). The average HTLV-1 particle diameter determined by cryo-TEM and FFS was 71 ± 20 nm and 75 ± 4 nm, respectively. These values are significantly smaller than previous estimates made of HTLV-1 particles by negative staining TEM. Furthermore, cryo-TEM reveals that the majority of HTLV-1 VLPs lacks an ordered structure of the Gag lattice, suggesting that the HTLV-1 Gag shell is very likely to be organized differently compared to that observed with HIV-1 Gag in immature particles. This conclusion is supported by our observation that the average copy number of HTLV-1 Gag per particle is estimated to be 510 based on FFS, which is significantly lower than that found for HIV-1 immature virions. Conclusions In summary, our studies represent the first quantitative biophysical analysis of HTLV-1-like particles and reveal novel insights into particle morphology and Gag stochiometry.

Abstract Background The effect of additional treatment strategies with antineoplastic agents on intraperitoneal tumor stimulating interleukin levels are unclear. Taurolidine and Povidone-iodine have been mainly used for abdominal lavage in Germany and Europe. Methods In the settings of a multicentre (three University Hospitals) prospective randomized controlled trial 120 patients were randomly allocated to receive either 0.5% taurolidine/2,500 IU heparin (TRD) or 0.25% povidone-iodine (control) intraperitoneally for resectable colorectal, gastric or pancreatic cancers. Due to the fact that IL-1beta (produced by macrophages) is preoperatively indifferent in various gastrointestinal cancer types our major outcome criterion was the perioperative (overall) level of IL-1beta in peritoneal fluid. Results Cytokine values were significantly lower after TRD lavage for IL-1beta, IL-6, and IL-10. Perioperative complications did not differ. The median follow-up was 50.0 months. The overall mortality rate (28 vs. 25, p = 0.36), the cancer-related death rate (17 vs. 19, p = .2), the local recurrence rate (7 vs. 12, p = .16), the distant metastasis rate (13 vs. 18, p = 0.2) as well as the time to relapse were not statistically significant different. Conclusion Reduced cytokine levels might explain a short term antitumorigenic intraperitoneal effect of TRD. But, this study analyzed different types of cancer. Therefore, we set up a multicentre randomized trial in patients undergoing curative colorectal cancer resection. Trial registration ISRCTN66478538

Abstract Background The parvulin-type peptidyl prolyl cis/trans isomerase Par14 is highly conserved in all metazoans. The recently identified parvulin Par17 contains an additional N-terminal domain whose occurrence and function was the focus of the present study. Results Based on the observation that the human genome encodes Par17, but bovine and rodent genomes do not, Par17 exon sequences from 10 different primate species were cloned and sequenced. Par17 is encoded in the genomes of Hominidae species including humans, but is absent from other mammalian species. In contrast to Par14, endogenous Par17 was found in mitochondrial and membrane fractions of human cell lysates. Fluorescence of EGFP fusions of Par17, but not Par14, co-localized with mitochondrial staining. Par14 and Par17 associated with isolated human, rat and yeast mitochondria at low salt concentrations, but only the Par17 mitochondrial association was resistant to higher salt concentrations. Par17 was imported into mitochondria in a time and membrane potential-dependent manner, where it reached the mitochondrial matrix. Moreover, Par17 was shown to bind to double-stranded DNA under physiological salt conditions. Conclusion Taken together, the DNA binding parvulin Par17 is targeted to the mitochondrial matrix by the most recently evolved mitochondrial prepeptide known to date, thus adding a novel protein constituent to the mitochondrial proteome of Hominidae.

A dual functional chain transfer agent (CTA) capable of highly efficient sequential thermal and photoinduced ligation, generating α,ω-functional polymers, is introduced. The newly designed CTA (1-(4-((2-formyl-3-methyl phenoxy)methyl)phenyl)ethyl (diethoxyphosphoryl)methane dithioate) fuses thermally triggered hetero Diels-Alder chemistry with rapid light-induced photoenol chemistry. The versatility of the CTA is exemplarily demonstrated via the preparation of an amphiphilic triblock quaterpolymer poly(isoprene- co -styrene)- block -poly(ethyl acrylate)- block -poly(ethylene oxide) (P(I- co -S)- b -PEA- b -PEO). Subsequent to the homopolymerization of ethyl acrylate (PEA), a Cp-functional poly(isoprene- co -styrene) (P(I- co -S)) is conjugated with the electron-deficient C═S double bond (dienophile) of the CTA end group, generating a P(I- co -S)- b -PEA diblock terpolymer. The triblock quaterpolymer P(I- co -S)- b -PEA- b -PEO is generated by photoligation of a macromolecular dienophile, i.e., the fumarate-terminated poly(ethylene oxide) (PEO-fum) to the photoenol-functional P(I- co -S)- b -PEA. The new dual functional ligation RAFT agent constitutes a technology platform for generating α,ω-reactive building blocks from one single chain transfer agent.

Materials interfaces--with a gas, a liquid, or another solid--are highly important for advanced applications. Besides their topological design, controlling interactions at these interfaces is typically realized by tuning the chemical composition of the materials surface. In areas such as nanoscience or biology, it is, however, highly desirable to impart heterogeneously distributed properties. Photopatterning, more than micro- and nanoprinting methods, is often the method of choice for precise functionalization, especially in terms of versatility. Recently, a range of new or rediscovered photochemistry approaches have been applied to precision surface functionalization, with the common aim of increasing efficiency and resolution while concomitantly lowering the amount of required energy. A survey of such methods is presented in this Review, with a focus on those we have explored., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A rapid and catalyst-free cycloaddition system for visible-light-induced click chemistry is reported. A readily accessible photoreactive 2H-azirine moiety was designed to absorb light at wavelengths above 400 nm. Irradiation with low-energy light sources thus enables efficient small-molecule synthesis with a diverse range of multiple-bond-containing compounds. Moreover, in order to demonstrate the efficiency of the current approach, quantitative ligation of the photoactivatable chromophore with functional polymeric substrates was performed and full conversion with irradiation times of only 1 min at ambient conditions was achieved. The current report thus presents a highly efficient method for applications involving selective cycloaddition to electron-deficient multiple-bond-containing materials., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)