Horizontal transfer of the blaNDM-1 gene to Pseudomonas aeruginosa and Acinetobacter baumannii in biofilms

Horizontal gene transfer has contributed to the global spread of the blaNDM-1 gene. Multiple studies have demonstrated plasmid transfer of blaNDM-1 between Gram-negative bacteria, primarily Enterobacteriaceae species, but conjugational transfer of natural blaNDM-1 plasmids from Enterobacteriaceae into Pseudomonas aeruginosa and Acinetobacter baumannii has not previously been shown. As P. aeruginosa and A. baumannii are both typically strong biofilm-formers, transfer of natural blaNDM-1 plasmids could potentially occur more readily in this environment. To determine whether natural blaNDM-1 plasmids could transfer to P. aeruginosa or A. baumannii in biofilms, three clinical and environmental Enterobacteriaceae strains carrying NDM-1-encoding plasmids of different incompatibility types were mated with E. coli J53, producing E. coli J53- blaNDM-1 transconjugants. Subsequently, dual-species biofilms were created using the E. coli J53 transconjugants as plasmid donors and either P. aeruginosa or A. baumannii as recipients. Biofilm transfer of NDM-encoding plasmids to P. aeruginosa and A. baumannii was successful from one and two E. coli J53- blaNDM-1 transconjugants, respectively. This demonstrates the potential for the spread of blaNDM-1, genes to P. aeruginosa and A. baumannii in clinical and environmental settings

CD34+/M-cadherin+ Bone Marrow Progenitor Cells Promote Arteriogenesis in Ischemic Hindlimbs of ApoE−/− Mice

BACKGROUND: Cell-based therapy shows promise in treating peripheral arterial disease (PAD); however, the optimal cell type and long-term efficacy are unknown. In this study, we identified a novel subpopulation of adult progenitor cells positive for CD34 and M-cadherin (CD34⁺/M-cad⁺ BMCs) in mouse and human bone marrow. We also examined the long-lasting therapeutic efficacy of mouse CD34⁺/M-cad⁺ BMCs in restoring blood flow and promoting vascularization in an atherosclerotic mouse model of PAD. METHODS AND FINDINGS: Colony-forming cell assays and flow cytometry analysis showed that CD34⁺/M-cad⁺ BMCs have hematopoietic progenitor properties. When delivered intra-arterially into the ischemic hindlimbs of ApoE⁻/⁻ mice, CD34⁺/M-cad⁺ BMCs alleviated ischemia and significantly improved blood flow compared with CD34⁺/M-cad⁻ BMCs, CD34⁻/M-cad⁺ BMCs, or unselected BMCs. Significantly more arterioles were seen in CD34⁺/M-cad⁺ cell-treated limbs than in any other treatment group 60 days after cell therapy. Furthermore, histologic assessment and morphometric analyses of hindlimbs treated with GFP⁺ CD34⁺/M-cad⁺ cells showed that injected cells incorporated into solid tissue structures at 21 days. Confocal microscopic examination of GFP⁺ CD34⁺/M-cad⁺ cell-treated ischemic legs followed by immunostaining indicated the vascular differentiation of CD34⁺/M-cad⁺ progenitor cells. A cytokine antibody array revealed that CD34⁺/M-cad⁺ cell-conditioned medium contained higher levels of cytokines in a unique pattern, including bFGF, CRG-2, EGF, Flt-3 ligand, IGF-1, SDF-1, and VEGFR-3, than did CD34⁺/M-cad⁻ cell-conditioned medium. The proangiogenic cytokines secreted by CD34⁺/M-cad⁺ cells induced oxygen- and nutrient-depleted endothelial cell sprouting significantly better than CD34⁺/M-cad⁻ cells during hypoxia. CONCLUSION: CD34⁺/M-cad⁺ BMCs represent a new progenitor cell type that effectively alleviates hindlimb ischemia in ApoE⁻/⁻ mice by consistently improving blood flow and promoting arteriogenesis. Additionally, CD34⁺/M-cad⁺ BMCs contribute to microvascular remodeling by differentiating into vascular cells and releasing proangiogenic cytokines and growth factors

31st Annual Meeting and Associated Programs of the Society for Immunotherapy of Cancer (SITC 2016) : part two

Background The immunological escape of tumors represents one of the main ob- stacles to the treatment of malignancies. The blockade of PD-1 or CTLA-4 receptors represented a milestone in the history of immunotherapy. However, immune checkpoint inhibitors seem to be effective in specific cohorts of patients. It has been proposed that their efficacy relies on the presence of an immunological response. Thus, we hypothesized that disruption of the PD-L1/PD-1 axis would synergize with our oncolytic vaccine platform PeptiCRAd. Methods We used murine B16OVA in vivo tumor models and flow cytometry analysis to investigate the immunological background. Results First, we found that high-burden B16OVA tumors were refractory to combination immunotherapy. However, with a more aggressive schedule, tumors with a lower burden were more susceptible to the combination of PeptiCRAd and PD-L1 blockade. The therapy signifi- cantly increased the median survival of mice (Fig. 7). Interestingly, the reduced growth of contralaterally injected B16F10 cells sug- gested the presence of a long lasting immunological memory also against non-targeted antigens. Concerning the functional state of tumor infiltrating lymphocytes (TILs), we found that all the immune therapies would enhance the percentage of activated (PD-1pos TIM- 3neg) T lymphocytes and reduce the amount of exhausted (PD-1pos TIM-3pos) cells compared to placebo. As expected, we found that PeptiCRAd monotherapy could increase the number of antigen spe- cific CD8+ T cells compared to other treatments. However, only the combination with PD-L1 blockade could significantly increase the ra- tio between activated and exhausted pentamer positive cells (p= 0.0058), suggesting that by disrupting the PD-1/PD-L1 axis we could decrease the amount of dysfunctional antigen specific T cells. We ob- served that the anatomical location deeply influenced the state of CD4+ and CD8+ T lymphocytes. In fact, TIM-3 expression was in- creased by 2 fold on TILs compared to splenic and lymphoid T cells. In the CD8+ compartment, the expression of PD-1 on the surface seemed to be restricted to the tumor micro-environment, while CD4 + T cells had a high expression of PD-1 also in lymphoid organs. Interestingly, we found that the levels of PD-1 were significantly higher on CD8+ T cells than on CD4+ T cells into the tumor micro- environment (p < 0.0001). Conclusions In conclusion, we demonstrated that the efficacy of immune check- point inhibitors might be strongly enhanced by their combination with cancer vaccines. PeptiCRAd was able to increase the number of antigen-specific T cells and PD-L1 blockade prevented their exhaus- tion, resulting in long-lasting immunological memory and increased median survival

Spatial analysis of factors associated with household subscription to the National Health Insurance Scheme in rural Ghana

The use of health insurance schemes in financing healthcare delivery and to minimize the poverty gap is gaining considerable recognition among the least developed and resource challenged countries around the world. With the implementation of the socialized health insurance scheme, Ghana has taken the lead in Sub-Saharan Africa and now working out further strategies to gain universal coverage among her citizenry. The primary goal of this study is to explore the spatial relationship between the residential homes and demographic features of the people in the Barekese subdistrict in Ghana on the probability to enroll the entire household unit in the National Health Insurance Scheme (NHIS). Household level data were gathered from 20 communities on the enrollment status into the NHIS alongside demographic and socioeconomic indicators and the spatial location of every household that participated in the study. Kulldorff’s purely spatial scan statistic was used to detect geographic clusters of areas with participatory households that have either higher or lower enrollment patterns in the insurance program. Logistic regression models on selected demographic and socioeconomic indicators were built to predict the effect on the odds of enrolling an entire household membership in the NHIS. Three clusters significantly stood out to have either high or low enrollment patterns in the health insurance program taking into accounts the number of households in those sub-zones of the study region. Households in the Cluster 1 insurance group have very high travel expenses compared to their counterparts in the other idenfied clusters. Travel cost and time to the NHIS registration center to enroll in the program were both significant predictors to participation in the program when controlling for cluster effect. Residents in the High socioeconomic group have about 1.66 [95% CI: 1.27-2.17] times the odds to enroll complete households in the insurance program compared to their counterparts in the Low socioeconomic group. The study demonstrated the use of spatial analytical tools to identify clusters of household enrollment pattern in the NHIS among residents in rural Ghana. In the face of limited resources, policy makers can therefore use the findings as guideline to strategically channel interventions to areas of most need. Furthermore, these analyses can be repeated annually to assess progress on improving insurance coverage

Evaluation of the Sex-and-Age-Specific Effects of PM2.5 on Hospital Readmission in the Presence of the Competing Risk of Mortality in the Medicare Population of Utah 1999–2009

Acute ambient air pollution exposure increases risk of cardiac events. We evaluated sex-and-age-specific effects of PM2.5 on hospital readmission and death among 19,602 Medicare beneficiaries (Nevents = 30,510) who survived cardiovascular events including myocardial infarction (MI), heart failure (HF), ischemic heart disease (IHD), and cardiac arrhythmias in Utah from 1999&ndash;2009. Fine and Gray regression jointly modeled the effect of PM2.5 on readmission hazard rates while allowing for the competing risk of death. Models were stratified by age and sex and adjusted for Charlson Comorbidity Index, dual enrollment in Medicare Parts A and B, temperature, and household income. There were 2032 cardiac readmissions and 1420 deaths after discharge. Among males age 65&ndash;74 years admitted for HF, a 10 &mu;m/m3 increase in PM2.5 was associated with a 30% increase in risk of readmission (p = 0.01). Among females age 75&ndash;84 admitted for HF, PM2.5 was associated with a 22% increase in risk of readmission (p = 0.01). Among females age 75&ndash;84 years admitted for IHD, PM2.5 was associated with a 25% decrease in readmission (p = 0.01), however this was explained by a 36% increase in risk of death (p = 0.01). Exposure to PM2.5 was associated with increased risk of readmission and death. Associations were dependent upon age, sex, and index condition

Using Distributed Solar for Treatment of Drinking Water in Developing Countries

Unsafe drinking water is a major cause of disease in developing countries. Lack of adequate water treatment and delivery infrastructure, high operational costs and poor maintenance are some of the factors contributing to the problem. Many developing countries also have large population clusters in cities and inadequate sanitation services, which increase the risk of water- borne disease outbreak. Incorporating renewable energy sources for treatment and distribution of potable water may be the key to developing sustainable water supply systems to reduce water- borne diseases in developing countries. This study focused on evaluating the potential of using distributed solar for a 4.5 million gallons per day (MGD) existing drinking water treatment plant (DWTP), located in Sindh, Pakistan. The DWTP utilized a conventional treatment train, consisting of coagulation, flocculation, sedimentation, filtration and disinfection processes to treat water obtained from the Indus River. The DWTP was sized by designing the various unit processes involved and then the energy consumption associated with each unit process was determined. The results showed that the energy consumption was largest for the flash and rapid mixers. Existing land holdings were sufficient for the deployment of solar photovoltaics (PV) which was successfully incorporated into the design of the DWTP

Differential impacts of particulate air pollution exposure on early and late stages of spermatogenesis

Background: Despite increasing evidence that particulate air pollution has adverse effects on human semen quality, few studies examine the impact of air pollution on clinically relevant thresholds used to diagnose male fertility problems. Furthermore, exposure is often assessed using average air pollution levels in a geographic area rather than individualized estimates. Finally, physiologically-informed exposure windows are inconsistent. Objectives: We sought to test the hypothesis that airborne particulate exposures during early-phase spermatogenesis will have a differential impact on spermatogenic formation compared to late-phase exposures, using an individualized model of exposure to particulate matter ≤ 2.5 µm and ≤ 10 µm (PM2.5 and PM10, respectively). Methods: From an original cohort of 183 couples, we conducted a retrospective analysis of 130 healthy males seeking to become parents, using spermatogenesis-relevant exposure windows of 77–34 days and 37–0 days prior to semen collection to encompass sperm development stages of mitosis/meiosis and spermiogenesis, respectively. Individualized residential exposure to PM2.5 and PM10 was estimated by selecting multiple air pollution sensors within the same geographic air basin as participants and employing inverse distance weighting to calculate mean daily exposure levels. We used multiple logistic regression to assess the association between pollution, temperature, and dichotomized World Health Organization semen parameters. Results: During the early phase of spermatogenesis, air pollution exposure is associated with 1.52 (95% CI: 1.04–2.32) times greater odds of < 30% normal heads per 1-unit increase in IQR for PM2.5. In the late phase of spermatogenesis, air pollution exposure is associated with 0.35 (95% CI: 0.10–0.74) times greater odds of semen concentration < 15 million/mL per 1-unit increase in IQR for PM2.5, and 0.28 (95% CI: 0.07–0.72) for PM10. Conclusion: Particulate exposure has a differential and more deleterious impact on sperm during early-phase spermatogenesis than late-phase