Effect of surface roughness and sterilization on bacterial adherence to ultra-high molecular weight polyethylene

AbstractSterilization with ethylene oxide (EO) and gas plasma (GP) are well-known methods applied to ultra-high molecular weight polyethylene (UHMWPE) surfaces in the belief that they prevent major material changes caused by gamma irradiation. However, the influence of these surface sterilization methods on bacterial adherence to UHMWPE is unknown. UHMWPE samples with various degrees of roughness (0.3, 0.8 and 2.0 µm) were sterilized with either GP or EO. The variations in hydrophobicity, surface free energy and surface functional groups were investigated before and after sterilization. Sterilized samples were incubated with either Staphylococcus aureus or Staphylococcus epidermidis in order to study bacterial adherence to these materials. Fewer bacteria adhered to UHMWPE after sterilization with EO than after sterilization with GP, especially to the smoothest surfaces. No changes in chemical composition of the UHMWPE surface due to sterilization were observed using X-ray photoemission spectroscopy analysis. The decreased bacterial adherence to UHMWPE found at the smoothest surfaces after sterilization with EO was not directly related to changes in chemical composition. Increased bacterial adherence to rougher surfaces was associated with increased polar surface energy of EO-sterilized surfaces

HIV/STI co-infection among men who have sex with men in Spain

In Spain, neither the HIV nor the STI national surveillance systems collect information on HIV/STI co-infection. However, there are two networks based on HIV/STI clinics which gather this data. We describe HIV prevalence in men who have sex with men (MSM) diagnosed with infectious syphilis and/or gonorrhoea in 15 STI clinics; and concurrent diagnoses of STI in MSM newly diagnosed with HIV in 19 HIV/STI clinics. In total, 572 MSM were diagnosed with infectious syphilis and 580 with gonorrhoea during 2005-2007. HIV prevalence among syphilis and gonorrhoea cases was 29.8% and 15.2% respectively. In the multivariate analysis, HIV/syphilis co-infection was associated with being Latin American; having a history of STI; reporting exclusively anal intercourse; and having sex with casual or several types of partners. HIV and gonorrhoea co-infection was associated with age older than 45 years; having no education or only primary education completed; and having a history of STI. In total, 1,462 HIV infections were newly diagnosed among MSM during 2003-2007. Of these, 31.0% were diagnosed with other STI at the same time. Factors associated with STI co-infection among new HIV cases in MSM were being Latin American; and having sex with casual partners or with both steady and casual partners. In Spain, a considerable proportion of MSM are co-infected with HIV and STI.This work was funded by two grants (36646/07; 36794/08) from the Foundation for Research and Prevention of AIDS in Spain (Fundación para la Investigación y la Prevención del SIDA en España–FIPSE).S

Mercury, cadmium, and lead levels in human placenta: a systematic review

BACKGROUND: Placental tissue may furnish information on the exposure of both mother and fetus. Mercury (Hg), cadmium (Cd), and lead (Pb) are toxicants of interest in pregnancy because they are associated with alterations in child development. OBJECTIVES: The aim of this study was to summarize the available information regarding total Hg, Cd, and Pb levels in human placenta and possible related factors. METHODS: We performed a systematic search of PubMed/MEDLINE, EMBASE, Lilacs, OSH, and Web of Science for original papers on total Hg, Cd, or Pb levels in human placenta that were published in English or Spanish (1976-2011). Data on study design, population characteristics, collection and analysis of placenta specimens, and main results were extracted using a standardized form. RESULTS: We found a total of 79 papers (73 different studies). Hg, Cd, and Pb levels were reported in 24, 46, and 46 studies, respectively. Most studies included small convenience samples of healthy pregnant women. Studies were heterogeneous regarding populations selected, processing of specimens, and presentation of results. Hg concentrations > 50 ng/g were found in China (Shanghai), Japan, and the Faroe Islands. Cd levels ranged from 1.2 ng/g to 53 ng/g and were highest in the United States, Japan, and Eastern Europe. Pb showed the greatest variability, with levels ranging from 1.18 ng/g in China (Shanghai) to 500 ng/g in a polluted area of Poland. CONCLUSION: The use of the placenta as a biomarker to assess heavy metals exposure is not properly developed because of heterogeneity among the studies. International standardized protocols are needed to enhance comparability and increase the usefulness of this promising tissue in biomonitoring studies.We thank the librarians of the Móstoles Hospital and of the National Health Sciences Library (ISCIII).S

The highly prevalent BRCA2 mutation c.2808_2811del (3036delACAA) is located in a mutational hotspot and has multiple origins

BRCA2-c.2808_2811del (3036delACAA) is one of the most reported germ line mutations in non-Ashkenazi breast cancer patients. We investigated its genetic origin in 51 Spanish carrier families that were genotyped with 11 13q polymorphic markers. Three independent associated haplotypes were clearly distinguished accounting for 23 [west Castilla y León (WCL)], 20 [east Castilla y León (ECL)] and 6 (South of Spain) families. Mutation age was estimated with the Disequilibrium Mapping using Likelihood Estimation software in a range of 45–68 and 45–71 generations for WCL and ECL haplotypes, respectively. The most prevalent variants, c.2808_2811del and c.2803G > A, were located in a double-hairpin loop structure (c.2794–c.2825) predicted by Quikfold that was proposed as a mutational hotspot. To check this hypothesis, random mutagenesis was performed over a 923 bp fragment of BRCA2, and 86 DNA variants were characterized. Interestingly, three mutations reported in the mutation databases (c.2680G > A, c.2944del and c.2957dup) were replicated and 20 affected the same position with different nucleotide changes. Moreover, five variants were placed in the same hairpin loop of c.2808_2811del, and one affected the same position (c.2808A > G). In conclusion, our results support that at least three different mutational events occurred to generate c.2808_2811del. Other highly prevalent DNA variants, such as BRCA1-c.68_69delAG, BRCA2- c.5946delT and c.8537delAG, are concentrated in hairpin loops, suggesting that these structures may represent mutational hotspots

Immunogenic Profiling in Mice of a HIV/AIDS Vaccine Candidate (MVA-B) Expressing Four HIV-1 Antigens and Potentiation by Specific Gene Deletions

BACKGROUND: The immune parameters of HIV/AIDS vaccine candidates that might be relevant in protection against HIV-1 infection are still undefined. The highly attenuated poxvirus strain MVA is one of the most promising vectors to be use as HIV-1 vaccine. We have previously described a recombinant MVA expressing HIV-1 Env, Gag, Pol and Nef antigens from clade B (referred as MVA-B), that induced HIV-1-specific immune responses in different animal models and gene signatures in human dendritic cells (DCs) with immunoregulatory function. METHODOLOGY/PRINCIPAL FINDINGS: In an effort to characterize in more detail the immunogenic profile of MVA-B and to improve its immunogenicity we have generated a new vector lacking two genes (A41L and B16R), known to counteract host immune responses by blocking the action of CC-chemokines and of interleukin 1beta, respectively (referred as MVA-B DeltaA41L/DeltaB16R). A DNA prime/MVA boost immunization protocol was used to compare the adaptive and memory HIV-1 specific immune responses induced in mice by the parental MVA-B and by the double deletion mutant MVA-B DeltaA41L/DeltaB16R. Flow cytometry analysis revealed that both vectors triggered HIV-1-specific CD4(+) and CD8(+) T cells, with the CD8(+) T-cell compartment responsible for >91.9% of the total HIV-1 responses in both immunization groups. However, MVA-B DeltaA41L/DeltaB16R enhanced the magnitude and polyfunctionality of the HIV-1-specific CD4(+) and CD8(+) T-cell immune responses. HIV-1-specific CD4(+) T-cell responses were polyfunctional and preferentially Env-specific in both immunization groups. Significantly, while MVA-B induced preferentially Env-specific CD8(+) T-cell responses, MVA-B DeltaA41L/DeltaB16R induced more GPN-specific CD8(+) T-cell responses, with an enhanced polyfunctional pattern. Both vectors were capable of producing similar levels of antibodies against Env. CONCLUSIONS/SIGNIFICANCE: These findings revealed that MVA-B and MVA-B DeltaA41L/DeltaB16R induced in mice robust, polyfunctional and durable T-cell responses to HIV-1 antigens, but the double deletion mutant showed enhanced magnitude and quality of HIV-1 adaptive and memory responses. Our observations are relevant in the immune evaluation of MVA-B and on improvements of MVA vectors as HIV-1 vaccines

Systems Analysis of MVA-C Induced Immune Response Reveals Its Significance as a Vaccine Candidate against HIV/AIDS of Clade C

Based on the partial efficacy of the HIV/AIDS Thai trial (RV144) with a canarypox vector prime and protein boost, attenuated poxvirus recombinants expressing HIV-1 antigens are increasingly sought as vaccine candidates against HIV/AIDS. Here we describe using systems analysis the biological and immunological characteristics of the attenuated vaccinia virus Ankara strain expressing the HIV-1 antigens Env/Gag-Pol-Nef of HIV-1 of clade C (referred as MVA-C). MVA-C infection of human monocyte derived dendritic cells (moDCs) induced the expression of HIV-1 antigens at high levels from 2 to 8 hpi and triggered moDCs maturation as revealed by enhanced expression of HLA-DR, CD86, CD40, HLA-A2, and CD80 molecules. Infection ex vivo of purified mDC and pDC with MVA-C induced the expression of immunoregulatory pathways associated with antiviral responses, antigen presentation, T cell and B cell responses. Similarly, human whole blood or primary macrophages infected with MVA-C express high levels of proinflammatory cytokines and chemokines involved with T cell activation. The vector MVA-C has the ability to cross-present antigens to HIV-specific CD8 T cells in vitro and to increase CD8 T cell proliferation in a dose-dependent manner. The immunogenic profiling in mice after DNA-C prime/MVA-C boost combination revealed activation of HIV-1-specific CD4 and CD8 T cell memory responses that are polyfunctional and with effector memory phenotype. Env-specific IgG binding antibodies were also produced in animals receiving DNA-C prime/MVA-C boost. Our systems analysis of profiling immune response to MVA-C infection highlights the potential benefit of MVA-C as vaccine candidate against HIV/AIDS for clade C, the prevalent subtype virus in the most affected areas of the world

Insertion of Vaccinia Virus C7L Host Range Gene into NYVAC-B Genome Potentiates Immune Responses against HIV-1 Antigens

Background: The highly attenuated vaccinia virus strain NYVAC expressing HIV-1 components has been evaluated as a vaccine candidate in preclinical and clinical trials with encouraging results. We have previously described that the presence of C7L in the NYVAC genome prevents the induction of apoptosis and renders the vector capable of replication in human and murine cell lines while maintaining an attenuated phenotype in mice. Methodology/Principal Findings: In an effort to improve the immunogenicity of NYVAC, we have developed a novel poxvirus vector by inserting the VACV host-range C7L gene into the genome of NYVAC-B, a recombinant virus that expresses four HIV-1 antigens from clade B (Env, Gag, Pol and Nef) (referred as NYVAC-B-C7L). In the present study, we have compared the in vitro and in vivo behavior of NYVAC-B and NYVAC-B-C7L. In cultured cells, NYVAC-B-C7L expresses higher levels of heterologous antigen than NYVAC-B as determined by Western blot and fluorescent-activated cell sorting to score Gag expressing cells. In a DNA prime/poxvirus boost approach with BALB/c mice, both recombinants elicited robust, broad and multifunctional antigen-specific T-cell responses to the HIV-1 immunogens expressed from the vectors. However, the use of NYVAC-B-C7L as booster significantly enhanced the magnitude of the T cell responses, and induced a more balanced cellular immune response to the HIV-1 antigens in comparison to that elicited in animals boosted with NYVAC-B. Conclusions/Significance: These findings demonstrate the possibility to enhance the immunogenicity of the highl

Infection control, genetic assessment of drug resistance and drug susceptibility testing in the current management of multidrug/extensively-resistant tuberculosis (M/XDR-TB) in Europe: A tuberculosis network European Trialsgroup (TBNET) study

Aim Europe has the highest documented caseload and greatest increase in multidrug and extensively drug-resistant tuberculosis (M/XDR-TB) of all World Health Organization (WHO) regions. This survey examines how recommendations for M/XDR-TB management are being implemented. Methods TBNET is a pan-European clinical research collaboration for tuberculosis. An email survey of TBNET members collected data in relation to infection control, access to molecular tests and basic microbiology with drug sensitivity testing. Results 68/105 responses gave valid information and were from countries within the WHO European Region. Inpatient beds matched demand, but single rooms with negative pressure were only available in low incidence countries; ultraviolet decontamination was used in 5 sites, all with >10 patients with M/XDR-TB per year. Molecular tests for mutations associated with rifampicin resistance were widely available (88%), even in lower income and especially in high incidence countries. Molecular tests for other first line and second line drugs were less accessible (76 and 52% respectively). A third of physicians considered that drug susceptibility results were delayed by > 2 months. Conclusion Infection control for inpatients with M/XDR-TB remains a problem in high incidence countries. Rifampicin resistance is readily detected, but tests to plan regimens tailored to the drug susceptibilities of the strain of Mycobacterium tuberculosis are significantly delayed, allowing for further drug resistance to develop