Systems genetics uncover new loci containing functional gene candidates in Mycobacterium tuberculosis-infected Diversity Outbred mice.

Mycobacterium tuberculosis, the bacillus that causes tuberculosis (TB), infects 2 billion people across the globe, and results in 8-9 million new TB cases and 1-1.5 million deaths each year. Most patients have no known genetic basis that predisposes them to disease. We investigated the complex genetic basis of pulmonary TB by modelling human genetic diversity with the Diversity Outbred mouse population. When infected with M. tuberculosis, one-third develop early onset, rapidly progressive, necrotizing granulomas and succumb within 60 days. The remaining develop non-necrotizing granulomas and survive longer than 60 days. Genetic mapping using clinical indicators of disease, granuloma histopathological features, and immune response traits identified five new loci on mouse chromosomes 1, 2, 4, 16 and three previously identified loci on chromosomes 3 and 17. Quantitative trait loci (QTLs) on chromosomes 1, 16, and 17, associated with multiple correlated traits and had similar patterns of allele effects, suggesting these QTLs contain important genetic regulators of responses to M. tuberculosis. To narrow the list of candidate genes in QTLs, we used a machine learning strategy that integrated gene expression signatures from lungs of M. tuberculosis-infected Diversity Outbred mice with gene interaction networks, generating functional scores. The scores were then used to rank candidates for each mapped trait in each locus, resulting in 11 candidates: Ncf2, Fam20b, S100a8, S100a9, Itgb5, Fstl1, Zbtb20, Ddr1, Ier3, Vegfa, and Zfp318. Importantly, all 11 candidates have roles in infection, inflammation, cell migration, extracellular matrix remodeling, or intracellular signaling. Further, all candidates contain single nucleotide polymorphisms (SNPs), and some but not all SNPs were predicted to have deleterious consequences on protein functions. Multiple methods were used for validation including (i) a statistical method that showed Diversity Outbred mice carrying PWH/PhJ alleles on chromosome 17 QTL have shorter survival; (ii) quantification of S100A8 protein levels, confirming predicted allele effects; and (iii) infection of C57BL/6 mice deficient for the S100a8 gene. Overall, this work demonstrates that systems genetics using Diversity Outbred mice can identify new (and known) QTLs and new functionally relevant gene candidates that may be major regulators of granuloma necrosis and acute inflammation in pulmonary TB.

Changes in quality of life after a diagnosis of cancer: a 2-year study comparing breast cancer and melanoma patients.

PURPOSE: Longitudinal studies addressing change in health-related quality of life (HRQoL) following a diagnosis of cancer have mainly focused on a single cancer type, and little is known about the differences in HRQoL over time according to the type of tumor. The current study aims to compare the change in HRQoL over 2 years following breast cancer or melanoma diagnosis and socio-demographic variables associated with HRQoL over time. METHODS: Patients recently diagnosed with breast cancer (n = 215) or melanoma (n = 78) completed surveys within 1 month of diagnosis and 6, 12, and 24 months later. Multilevel modeling analyses were used to compare the evolution over time of HRQoL dimensions, as measured by the EORTC QLQ-C30, in both cancers. Longitudinal effect of socio-demographic variables on HRQoL was also assessed. RESULTS: Consistent with the literature, both cancer patients experienced decreased HRQoL scores following the diagnosis before improving over time. However, our analyses revealed that this rebound effect may occur at diverse times over the course of the illness according to the type of cancer. In addition, HRQoL over time was positively associated with age and negatively related to living with a partner regardless of the type of cancer. CONCLUSIONS: The results of the present study suggest that support in hospital units should be specific and depend on the cancer type.

Growth control, structure, chemical state, and photoresponse of CuO-CdS core-shell heterostructure nanowires.

The growth of single-crystal CuO nanowires by thermal annealing of copper thin films in air is studied. We show that the density, length, and diameter of the nanowires can be controlled by tuning the morphology and structure of the copper thin films deposited by DC magnetron sputtering. After identifying the optimal conditions for the growth of CuO nanowires, chemical bath deposition is employed to coat the CuO nanowires with CdS in order to form p-n nanojunction arrays. As revealed by high-resolution TEM analysis, the thickness of the polycrystalline CdS shell increases when decreasing the diameter of the CuO core for a given time of CdS deposition. Near-edge x-ray absorption fine-structure spectroscopy combined with transmission x-ray microscopy allows the chemical analysis of isolated nanowires. The absence of modification in the spectra at the Cu L and O K edges after the deposition of CdS on the CuO nanowires indicates that neither Cd nor S diffuse into the CuO phase. We further demonstrate that the core-shell nanowires exhibit the I-V characteristic of a resistor instead of a diode. The electrical behavior of the device was found to be photosensitive, since increasing the incident light intensity induces an increase in the collected electrical current.

Fabrication of a nickel nanowire mesh electrode suspended on polymer substrate.

We report on an efficient strategy for the fabrication of an ultra-long suspended nanowire mesh suitable for nanodevice architectures on a polymer surface. First, nickel nanowires are synthesized directly on a template substrate by magnetron sputtering. Laser interference lithography followed by deep reactive ion etching is used to create the nanograted template substrate constituted of one-dimensional line pattern arrays of 240 nm in periodicity. Ordered alignment of ultra-long nanowires (∼180 nm in diameter) with high fidelity to the template pattern is observed by scanning electron microscopy. The transfer of the pre-defined parallel nanowire array from the template surface to a target polymer substrate for electrical characterization of the system is demonstrated. The electrical behaviour of the nanowire mesh, suspended between two electrodes, was found to be linear, stable, and reproducible. This result suggests that this nanofabrication process will open an efficient way to the design and construction of novel nanodevices.

Comparative efficacies of human simulated exposures of tedizolid and linezolid against Staphylococcus aureus in the murine thigh infection model.

Tedizolid (formally torezolid) is an expanded-spectrum oxazolidinone with enhanced in vitro potency against Gram-positive pathogens, including methicillin-susceptible Staphylococcus aureus (MSSA) and methicillin-resistant S. aureus (MRSA). The efficacies of human simulated exposures of tedizolid and linezolid against S. aureus in an immunocompetent mouse thigh model over 3 days were compared. Four strains of MRSA and one of MSSA with tedizolid and linezolid MICs ranging from 0.25 to 0.5 and from 2 to 4 µg/ml, respectively, were utilized. Tedizolid or linezolid was administered in a regimen simulating a human steady-state 24-h area under the free concentration-time curve of 200 mg every 24 h (Q24) or 600 mg Q12, respectively. Thighs were harvested after 4, 8, 12, 24, 36, 48, and 72 h, and efficacy was determined by the change in bacterial density. The mean bacterial density in control mice increased over the 3-day period. After 24 h of treatment, a reduction in bacterial density of ≥1 log CFU was observed for both the tedizolid and linezolid treatments. Antibacterial activity was enhanced for both agents with a reduction of ≥2.6 log CFU after 72 h of treatment. Any statistically significant differences (P ≤ 0.05) in efficacy between the agents were transient and did not persist throughout the 72-h treatment period. The tedizolid and linezolid regimens demonstrated similar in vivo efficacies against the S. aureus isolates tested. Both agents were bacteriostatic at 24 h and bactericidal on the third day of treatment. These data support the clinical utility of tedizolid for skin and skin structure infections caused by S. aureus, as well as the bactericidal activity of the oxazolidinones after 3 days of treatment.

A comparison of the clinical determinants of health-related quality of life and subjective well-being in long-term breast cancer survivors.

Research concerning long-term breast cancer survivors (BCS) has primarily analysed their health-related quality of life (HRQoL). However, other dimensions of life considered important by patients might be affected by cancer treatments as well. The aim of this paper is thus to compare the clinical determinants of HRQoL and of overall quality of life as described by measures of subjective well-being (SWB) in long-term BCS. SWB represents a person's own evaluation of their overall situation. A total of 321 French BCS diagnosed 5 to 15 years ago participated in a cross-sectional mailed survey. Outcome measures were the physical and mental health scores of the 36-item Short-Form survey and measures of SWB (happiness, life satisfaction and the positive and negative affect scales). Multivariate regression analyses suggest that HRQoL and SWB measures provide different pictures of the experience of breast cancer. Treatment type has no impact on HRQoL but is correlated with all our SWB measures while time since diagnosis positively affects physical health but not SWB. We conclude that it could be fruitful to analyse SWB, alongside the traditional study of HRQoL, in order to enhance our understanding of the various long-lasting consequences of breast cancer.

Hierarchical carbon nanostructure design: ultra-long carbon nanofibers decorated with carbon nanotubes.

Hierarchical carbon nanostructures based on ultra-long carbon nanofibers (CNF) decorated with carbon nanotubes (CNT) have been prepared using plasma processes. The nickel/carbon composite nanofibers, used as a support for the growth of CNT, were deposited on nanopatterned silicon substrate by a hybrid plasma process, combining magnetron sputtering and plasma-enhanced chemical vapor deposition (PECVD). Transmission electron microscopy revealed the presence of spherical nanoparticles randomly dispersed within the carbon nanofibers. The nickel nanoparticles have been used as a catalyst to initiate the growth of CNT by PECVD at 600°C. After the growth of CNT onto the ultra-long CNF, SEM imaging revealed the formation of hierarchical carbon nanostructures which consist of CNF sheathed with CNTs. Furthermore, we demonstrate that reducing the growth temperature of CNT to less than 500°C leads to the formation of carbon nanowalls on the CNF instead of CNT. This simple fabrication method allows an easy preparation of hierarchical carbon nanostructures over a large surface area, as well as a simple manipulation of such material in order to integrate it into nanodevices.

Titanium carbide/carbon composite nanofibers prepared by a plasma process.

The incorporation of metal or metal carbide nanoparticles into carbon nanofibers modifies their properties and enlarges their field of application. The purpose of this work is to report a new non-catalytic and easy method to prepare organized metal carbide-carbon composite nanofibers on nanopatterned silicon substrates prepared by laser interference lithography coupled with deep reactive ion etching. Titanium carbide-carbon composite nanofibers were grown on the top of the silicon lines parallel to the substrate by a hybrid plasma process combining physical vapor deposition and plasma enhanced chemical vapor deposition. The prepared nanofibers were analyzed by scanning electron microscopy, x-ray photoelectron spectroscopy, Raman spectroscopy and transmission electron microscopy. We demonstrate that the shape, microstructure and the chemical composition of the as-grown nanofibers can be tuned by changing the plasma conditions.

Klebsiella pneumoniae bacteraemia in a region of Canada.

The second case of magA+ rmpA+ hypermucoviscosity phenotype Klebsiella pneumoniae infection was documented in Canada, in an immigrant from Algeria. To ascertain whether this represented recent importation of the strain or local transmission within Canada, a retrospective study of K. pneumoniae bacteraemia was conducted in the region, from 1997 to 2007, and 411 episodes were identified. No epidemiological evidence for local transmission of this strain was found. However, for the first time, the population incidence of K. pneumoniae bacteraemia was determined, which increased by 82% between 1997 and 2007, from 10.2 to 18.7 per 100 000 inhabitants. Incidence increased dramatically with age and with the presence of diabetes, but remained stable over time within each stratum. The proportion of patients with K. pneumoniae bacteraemia who were diabetic increased from 26% (1997-2004) to 42% (2005-2007). The rising incidence of K. pneumoniae bacteraemia may represent an unexpected consequence of the expanding population of adult diabetics.

Integration of a carbon nanotube based electrode in silicon microtechnology to fabricate electrochemical transducers.

An original approach was developed and validated for the fabrication of a carbon nanotube (CNT) electrode synthesized directly onto a carbon buffer thin film deposited on a highly doped monocrystalline silicon surface. The buffer layer of amorphous carbon thin film was deposited by physical vapour deposition on the silicon substrate before CNT synthesis. For this purpose, nickel was deposited on the carbon buffer layer by an electrochemical procedure and used as a catalyst for the CNT growth. The CNT synthesis was achieved by plasma enhanced chemical vapour deposition (PECVD) in an electron cyclotron resonance (ECR) plasma chamber using a C(2)H(2)/NH(3) gas mixture. In order to evaluate the electrochemical behaviour of the CNT-based electrode, the carbon layer and the silicon/carbon interface were studied. The resulting buffer layer enhanced the electronic transport from the doped silicon to the CNTs. The electrode surface was studied by XPS and characterized by both SEM and TEM. The electrochemical response exhibited by the resulting electrodes modified with CNTs was also examined by cyclic voltammetry. The whole process was found to be compatible with silicon microtechnology and could be envisaged for the direct integration of microsensors on silicon chips.

In vivo immunomodulatory profile of telithromycin in a murine pneumococcal infection model.

In addition to bactericidal activity, macrolide antibacterials possess clinically relevant properties such as immunomodulatory activity. Whether such activity extends to novel antibacterials that are structurally related to macrolides, such as the ketolides, remains largely unknown. The objective of this study was to evaluate the in vivo immunomodulatory profile of the first ketolide antibacterial - telithromycin in a murine neutropenic thigh infection model. Specific pathogen-free, female ICR mice were rendered transiently neutropenic with intraperitoneal cyclophosphamide. Thighs were inoculated with 10(6) colony-forming units of a single clinical isolate of Streptococcus pneumoniae. Once inoculated, mice (n=500) received single oral doses of telithromycin (10, 25 or 50 mg/kg of body weight) or no treatment (control). Blood was obtained via cardiac puncture prior to and at 2, 4, 8, and 24 h after dose administration for determination of cytokine concentrations. Significant post-inoculation elevations of interleukin (IL)-1beta, IL-6, and IL-10 were noted in untreated controls over 24 h. Telithromycin attenuated these increases and the suppression of both IL-6 and IL-10 release was observed to be dose dependent. Systemic concentrations of IL-2 and tumor necrosis factor alpha showed an upward trend over the initial 8-h post-inoculation period in the telithromycin group. These data therefore reveal novel in vivo immunomodulatory effects of telithromycin. Further studies are warranted to determine whether such effects contribute to the therapeutic efficacy of the drug in patients with acute respiratory tract infections.

Autogenous bone grafts and bone substitutes--tools and techniques: I. A 20,000-case experience in maxillofacial and craniofacial surgery.

Alloplastic bone substitutes can be used to alter facial contour. In contrast, autogenous bone grafts have a successful 80-year history of restoring facial contour as well as the basic functional support of the craniofacial skeleton. The traditional procedures for harvesting and using autogenous bone grafts are not obsolete. During the past 30 years, the techniques have been refined and new sources have been found, such as calvarial grafts. New tools were required and have been designed to make harvesting of grafts easier and faster for the surgeon and safer and less expensive for the patient. Four short articles under the heading of "Techniques and Tools" are presented addressing the harvesting of (1) iliac, (2) costal, (3) tibial, and (4) calvarial grafts. These articles are based on the experience of six surgeons using the same technique and instruments in more than 20,000 autogenous bone grafting procedures. (These figures represent the group experience as of 2001. Since then, one of the junior coauthors has retired, but the remaining five continue to harvest autogenous bone grafts on a regular basis. So, the group experience as of 2004 is in the range of 23,000 procedures). The-senior surgeon's experience of 9500 procedures spans a period of 50 years (from 1946 to 1996). For the other surgeons (10,500 procedures combined), the collection period was 25 years (from 1975 to 2000).

Activation of human neutrophils in vitro and dieldrin-induced neutrophilic inflammation in vivo.

Many chemicals of environmental concern are known to alter the immune system and are considered toxic molecules because they affect immune cell functions. Inflammation related to environmental chemical exposure, however, is poorly documented, except that from air pollutants. In this study, we found that the organochlorine insecticide dieldrin could not alter the ability of human neutrophils to phagocytose opsonized sheep red blood cells at nonnecrotic concentrations (0.1, 1, 10, and 50 microM). However, dieldrin was found to increase human neutrophil superoxide production, RNA synthesis, and proinflammatory cytokine interleukin-8 production. The normal apoptotic rate of neutrophils evaluated by both cytology and flow cytometry (CD-16 staining) was not altered by dieldrin treatments, and this was correlated with its inability to inhibit spreading of neutrophils onto glass. Using the murine air pouch model, we found that dieldrin induces a neutrophilic inflammation. Taken together, these results demonstrated that dieldrin is a proinflammatory contaminant. To our knowledge, this is the first report establishing that dieldrin is a contaminant exhibiting proinflammatory properties. In addition, it is the first time that the murine air pouch model has been successfully used to confirm that a chemical of environmental concern can induce an inflammatory response in vivo.

The use of lymphocyte function-associated antigen (LFA)-1-deficient mice to determine the role of LFA-1, Mac-1, and alpha4 integrin in the inflammatory response of neutrophils.

After injury or infection, neutrophils rapidly migrate from the circulation into tissues by means of an orderly progression of adhesion receptor engagements. Neutrophils have been previously considered to use selectins exclusively to roll on vessels before an adhesion step mediated by the beta2 integrins, lymphocyte function-associated antigen (LFA)-1, and Mac-1. Here we use LFA-1(-/-) mice, function blocking monoclonal antibodies, and intravital microscopy to investigate the roles of LFA-1, Mac-1, and alpha4 integrins in neutrophil recruitment in vivo. For the first time, we show that LFA-1 makes a contribution to neutrophil rolling by stabilizing the transient attachment or tethering phase of rolling. In contrast, Mac-1 does not appear to be important for either rolling or firm adhesion, but instead contributes to emigration from the vessel. Blocking Mac-1 in the presence of LFA-1 significantly reduces emigration, suggesting cooperation between these two integrins. Low levels of alpha4beta1 integrin can be detected on neutrophils from LFA-1(+/+) and (-/-) mice. These cells make use of alpha4beta1 during the rolling phase, particularly in the absence of LFA-1. Thus LFA-1 and alpha4beta1, together with the selectins, are involved in the rolling phase of neutrophil recruitment, and, in turn, affect the later stages of the transmigration event.