Ligand Characteristics Important to Avidity Interactions of Multivalent Nanoparticles.

Multivalent interactions involve the engagement of multiple ligand-receptor pairs and are important in synthetic biology as design paradigms for targeted nanoparticles (NPs). However, little is known about the specific ligand parameters important to multivalent interactions. We employed a series of oligonucleotides as ligands conjugated to dendrimers as nanoparticles, and used complementary oligonucleotides on a functionalized SPR surface to measure binding. We compared the effect of ligand affinity to ligand number on the avidity characteristics of functionalized NPs. Changing the ligand affinity, either by changing the temperature of the system or by substitution noncomplementary base pairs into the oligonucleotides, had little effect on multivalent interaction; the overall avidity, number of ligands required for avidity per particle, and the number of particles showing avidity did not significantly change. We then made NP conjugates with the same oligonucleotide using an efficient copper-free click chemistry that resulted in essentially all of the NPs in the population exceeding the threshold ligand value. The particles exceeding the threshold ligand number again demonstrated high avidity interactions. This work validates the concept of a threshold ligand valence and suggests that the number of ligands per nanoparticle is the defining factor in achieving high avidity interactions.

Deregulation of DNA-dependent protein kinase catalytic subunit contributes to human hepatocarcinogenesis development and has a putative prognostic value.

BACKGROUND: The DNA-repair gene DNA-dependent kinase catalytic subunit (DNA-PKcs) favours or inhibits carcinogenesis, depending on the cancer type. Its role in human hepatocellular carcinoma (HCC) is unknown. METHODS: DNA-dependent protein kinase catalytic subunit, H2A histone family member X (H2AFX) and heat shock transcription factor-1 (HSF1) levels were assessed by immunohistochemistry and/or immunoblotting and qRT-PCR in a collection of human HCC. Rates of proliferation, apoptosis, microvessel density and genomic instability were also determined. Heat shock factor-1 cDNA or DNA-PKcs-specific siRNA were used to explore the role of both genes in HCC. Activator protein 1 (AP-1) binding to DNA-PKcs promoter was evaluated by chromatin immunoprecipitation. Kaplan-Meier curves and multivariate Cox model were used to study the impact on clinical outcome. RESULTS: Total and phosphorylated DNA-PKcs and H2AFX were upregulated in HCC. Activated DNA-PKcs positively correlated with HCC proliferation, genomic instability and microvessel density, and negatively with apoptosis and patient's survival. Proliferation decline and massive apoptosis followed DNA-PKcs silencing in HCC cell lines. Total and phosphorylated HSF1 protein, mRNA and activity were upregulated in HCC. Mechanistically, we demonstrated that HSF1 induces DNA-PKcs upregulation through the activation of the MAPK/JNK/AP-1 axis. CONCLUSION: DNA-dependent protein kinase catalytic subunit transduces HSF1 effects in HCC cells, and might represent a novel target and prognostic factor in human HCC.

Sustained analgesia achieved through esterase-activated morphine prodrugs complexed with PAMAM dendrimer.

PURPOSE: Design and evaluate the in vitro and in vivo efficacy of two extended release morphine formulations developed for IV administration by complexing esterase activated morphine prodrugs to surface-modified, generation 5 (G5) poly(amidoamine) (PAMAM) dendrimer. METHODS: Prodrugs were synthesized, complexed with PAMAM dendrimer, characterized via ultra performance liquid chromatography (UPLC), nuclear magnatic resonance (NMR), and tested in vitro using rat plasma vs. saline control and in an in vivo rat and guinea pig pain model (modified Randall and Selitto test). RESULTS: We demonstrated that complexation with dendrimer allowed the solubilization of the prodrugs for in vivo applications without the need for salt, and that the structural design of the morphine prodrugs allowed the controlled release of morphine which extended the action of morphine-induced analgesia in an animal pain model from 2 h (control) to 6 h (Morphine Prodrug A). CONCLUSION: The concept of complexing/solubilizing appropriately designed esterase-sensitive prodrugs with dendrimer to enhance the sustained release of these drugs may be a useful pharmacokinetic strategy for a range of therapeutics.

Fluorogenic 'click-on' dendrimer reporter for rapid profiling of cell proliferation.

The application of small molecule fluorescent reporters to monitor biological systems is limited by their poor water solubility and background fluorescence of these reporters. Herein, we describe the synthesis and testing of a fluorogenic 'click' dendrimer reporter to monitor cellular processes. The reporter system consists of a polyamidoamine (PAMAM) dendrimer conjugated with 3-azido-7-hydroxy coumarin. After the copper(I)-catalyzed azide-alkyne cycloaddition reaction ('click' reaction) with alkyne-derivatized target molecules, the natively non-fluorescent construct has a strong enhancement in fluorescence. This fluorogenic dendrimer reporter can be used to efficiently monitor biological processes and the specificity afforded by the 'click' reaction greatly reduces background noise and enhances assay flexibility. We used this fluorogenic dendrimer reporter to monitor incorporation of 5-ethynyl-2'-deoxyuridine (EdU) into newly synthesized DNA, as a surrogate marker of cellular proliferation. We anticipate that this new class of fluorogenic reporter can be used to monitor a wide array of molecules and lends itself to high-throughput profiling of biological systems.

A model for estimating costs and benefits of new vaccine technologies from the perspective of both buyers and sellers.

Although vaccination is widely considered one of the most cost-effective health interventions available, global coverage rates for many vaccines remain lower than necessary for disease elimination and eradication. New vaccine technologies can play an important role in addressing barriers to vaccination and increasing coverage rates. To identify and prioritize vaccine technology investments, decision makers must be able to compare the overall costs and benefits of each investment option. While these data points may exist, they are often confined to silos. Decision makers would benefit from a model that synthesizes this broad range of data and provides clear and actionable information. To facilitate vaccine investment, purchasing and deployment decisions, we developed a systematic and transparent cost-benefit model that estimates the value and risk of a given investment scenario from the perspective of both "buyers" (e.g., global donors, country governments) and "sellers" (e.g., developers, manufacturers) of vaccines. This model, which can be used to evaluate scenarios related to a single vaccine presentation or a portfolio of vaccine presentations, leverages our published approach for estimating the impact of improved vaccine technologies on vaccination coverage rates. This article presents a description of the model and provides an illustrative example application to a portfolio of measles-rubella vaccine technologies currently under development. Although the model is generally applicable to organizations involved in vaccine investment, manufacturing or purchasing, we believe it may be particularly useful to those engaged in vaccine markets that rely strongly on funding from institutional donors.

Exposure to psychotropic medications and COVID-19 course after hospital admission: Results from a prospective cohort study.

OBJECTIVE: There is evidence of a bidirectional association between COVID-19 disease and psychiatric disorders. We aimed to assess whether exposure to psychotropic medications prior to hospitalization was associated with mortality or discharge within 30 days after hospital admission. METHODS: In this prospective study, we included all individuals with a laboratory-confirmed COVID-19 infection who were admitted to the Bologna University Hospital between 1st March 2020 and 31st January 2021. We collected data about pre-existing psychiatric disorders and the use of psychotropic medications at the admission. As univariate analyses, we estimated cumulative incidence functions for 30-day mortality and discharge stratifying by exposure to each of the psychotropic medication classes. Finally, we fitted Cox regression models to estimate cause-specific Hazard Ratios (HR) of 30-day mortality and discharge. Results were adjusted for sociodemographic (age, sex), clinically relevant variables (comorbidity, c-reactive protein levels, severity of disease at presentation, history of smoking, study period), and psychiatric variables (psychiatric disorder diagnosis, number of psychotropic medications). RESULTS: Out of a total of 1238 hospitalized patients, 316 were prescribed psychotropic medications at the time of admission. Among these, 45 (3.6%) were taking a first-generation antipsychotics (FGA) and 66 (5.3%) a second generation antipsychotic (SGA). Exposure to SGA was associated with increased rates of 30-day mortality (HR = 2.01, 95%CI = 1.02-3.97) and exposure to FGA was associated with decreased rates of 30-day discharge (HR = 0.55, 95%CI = 0.33-0.90). CONCLUSION: Patients with COVID-19 infection exposed to FGA and SGA may have worse COVID-19 infection outcomes.

Bifunctional PAMAM dendrimer conjugates of folic acid and methotrexate with defined ratio.

Our group previously developed a multifunctional, targeted cancer therapeutic based on Generation 5 (G5) polyamidoamine (PAMAM) dendrimers. In those studies we conjugated the targeting molecule folic acid (FA) and the chemotherapeutic drug methotrexate (MTX) sequentially. This complex macromolecule was shown to selectively bind and kill KB tumor cells that overexpress folate receptor (FR) in vitro and in vivo. However, the multistep conjugation strategy employed in the synthesis of the molecule resulted in heterogeneous populations having differing numbers and ratios of the functionally antagonistic FA and MTX. This led to inconsistent and sometimes biologically inactive batches of molecules, especially during large-scale synthesis. We here resolved this issue by using a novel triazine scaffold approach that reduces the number of dendrimer conjugation steps required and allows for the synthesis of G5 conjugates with defined ratios of FA and MTX. Although an unoccupied γ-glutamyl carboxylate of FA has been previously suggested to be nonessential for FR binding, the functional requirement of an open α-carboxylate still remains unclear. In an attempt to also address this question, we have synthesized isomeric FA dendrimer conjugates (α-carboxyl or γ-carboxyl linked). Competitive binding studies revealed that both linkages have virtually identical affinity toward FR on KB cells. Our studies show that a novel bifunctional triazine-based conjugate G5-Triazine-γMTX-αFA with identical numbers of FA and MTX binds to FR through a polyvalent interaction and induces cytotoxicity in KB cells through FR-mediated cellular internalization, inducing higher toxicity as compared to conjugates synthesized by the multistep strategy. This work serves as a proof of concept for the development of bifunctional dendrimer conjugates that require a defined ratio of two functional molecules.

The facile synthesis of multifunctional PAMAM dendrimer conjugates through copper-free click chemistry.

The facile conjugation of three azido modified functionalities, namely a therapeutic drug (methotrexate), a targeting moiety (folic acid), and an imaging agent (fluorescein) with a G5 PAMAM dendrimer scaffold with cyclooctyne molecules at the surface through copper-free click chemistry is reported. Mono-, di-, and tri-functional PAMAM dendrimer conjugates can be obtained via combinatorial mixing of different azido modified functionalities simultaneously or sequentially with the dendrimer platform. Preliminary flow cytometry results indicate that the folic acid targeted nanoparticles are efficiently binding with KB cells.

Folate-targeted nanoparticles show efficacy in the treatment of inflammatory arthritis.

OBJECTIVE: To investigate the uptake of a poly(amidoamine) dendrimer (generation 5 [G5]) nanoparticle covalently conjugated to polyvalent folic acid (FA) as the targeting ligand into macrophages, and to investigate the activity of an FA- and methotrexate (MTX)-conjugated dendrimer (G5-FA-MTX) as a therapeutic for the inflammatory disease of arthritis. METHODS: In vitro studies were performed in macrophage cell lines and in isolated mouse macrophages to check the cellular uptake of fluorescence-tagged G5-FA nanoparticles, using flow cytometry and confocal microscopy. In vivo studies were conducted in a rat model of collagen-induced arthritis to evaluate the therapeutic potential of G5-FA-MTX. RESULTS: Folate-targeted dendrimer bound and internalized in a receptor-specific manner into both folate receptor ß-expressing macrophage cell lines and primary mouse macrophages. The conjugate G5-FA-MTX acted as a potent antiinflammatory agent and reduced arthritis-induced parameters of inflammation such as ankle swelling, paw volume, cartilage damage, bone resorption, and body weight decrease. CONCLUSION: The use of folate-targeted nanoparticles to specifically target MTX into macrophages may provide an effective clinical approach for antiinflammatory therapy in rheumatoid arthritis.

A method for estimating the impact of new vaccine technologies on vaccination coverage rates.

Vaccines are one of the most cost-effective tools for improving human health and well-being. The impact of a vaccine on population health is partly determined by its coverage rate, the proportion of eligible individuals vaccinated. Coverage rate is a function of the vaccine presentation and the population in which that presentation is deployed. This population includes not only the individuals vaccinated, but also the logistics and healthcare systems responsible for vaccine delivery. Because vaccine coverage rates remain below targets in many settings, vaccine manufacturers and purchasers have a shared interest in better understanding the relationship between vaccine presentation, population characteristics, and coverage rate. While there have been some efforts to describe this relationship, existing research and tools are limited in their ability to quantify coverage rate changes across a broad set of antigens, vaccine presentations, and geographies. In this article, we present a method for estimating the impact of improved vaccine technologies on vaccination coverage rates. It is designed for use with low- and middle-income country vaccination programs. This method uses publicly available data and simple calculations based on probability theory to generate coverage rate values. We first present the conceptual framework and mathematical approach. Using a Microsoft Excel-based implementation, we then apply the method to a vaccine technology in early-stage development: micro-array patch for a measles-rubella vaccine (MR-MAP). Example outputs indicate that a complete switch from the current subcutaneous presentation to MR-MAP in the 73 countries ever eligible for Gavi support would increase overall vaccination coverage by 3.0-4.9 percentage points depending on the final characteristics of the MR-MAP. This change equates to an additional 2.6-4.2 million children vaccinated per year. Our method can be readily extended to other antigens and vaccine technologies to provide quick, low-cost estimates of coverage impact. As vaccine manufacturers and purchasers face increasingly complex decisions, such estimates could facilitate objective comparisons between options and help these decision makers obtain the most value for money.

The current trends and challenges towards good community pharmacy practice and the way forward.

Background: The practice of pharmacy continues to evolve. Comprehensive research to monitor and assess the development of the practice is needed. Good Pharmacy Practices (GPP) have been adopted by many countries to enhance the quality of services. Little information is available concerning how pharmacy practices are being implemented in developing countries. Lebanon being a developing country is a good example where community pharmacy practice doesn't follow clear guidelines and no evidence of good clinical practice. Objectives: This study aims to highlight GPP implementation, to identify obstacles impeding implementation, and to suggest how its application could be facilitated in Lebanon. Methods: The review included studies published in English during the last five years covering aspects of pharmacy practice in relation to GPP standards. The search excluded research related to hospital pharmacy practice and primary health care centers since they have their own quality standards. Results: The research identified 20 recent studies that covered aspects of community pharmacy practice in Lebanon in relation to GPP standards. Eight of the studies related to research and professional development,5 related to the provision of medicines,4 related to interaction and communication,1 related to trainees,1 related to pharmacotherapy monitoring, and 1 related to documentation systems. An additional 6 studies provided insight into factors that affect the pharmacy practice in general. It is apparent that the pharmacy practice would benefit if pharmacists were better supported with financial incentives and a readjustment of their working conditions as this would have a positive impact on their productivity, job satisfaction, and overall well-being. The review indicated that the standard of research and professional development was the most studied topic and it was recommended that pharmacists develop their research capabilities. It was observed that there is a tendency towards implementing Continuous Education for pharmacists and obstacles primarily included work and family commitments, lack of interest, lack of time, difficulties in commuting, and lack of competence in the use of technology. This standard is aligned with the FIP's developmental goal of continuing professional development strategies. The search also identified only one pilot study to assess GGP compliance among community pharmacies in Lebanon. This pilot study was limited and showed low adherence of community pharmacies in Lebanon to GPP standards.Barriers to implementation are lack of enforcing laws,inadequate dissemination of the standards among the community pharmacists, poor public perception, and the financial and soscioeconomically crisis facing Lebanon. Conclusion: Collaborated efforts are needed to implement GPP standards in Lebanon.It is recommended to undergo training and awareness sessions to community pharmacists thus enhancing their commitment and motivation. It is also recommended to establish key performance indicators to monitor the implementation. Indicators should include structure indicators for regulating the storage of medications, process indicators for regulating the dispensing, and outcome indicators for reporting patient safety incidents, measuring public satisfaction and the provision and use of medicines.These recommendations can be used by Health authorities and Pharmacy educational institutions in Lebanon and in all similar low-income countries.

Public views of community pharmacy services during the COVID-19 pandemic: a national survey.

OBJECTIVE: To assess public opinion about community pharmacy services in Lebanon during the COVID-19 pandemic. METHOD: A cross-sectional study using an online questionnaire was conducted between April and August of 2021. A link was shared randomly among the Lebanese population using WhatsApp and Facebook. Public perceptions were explored within 3 different indicators: general services (B) dispensing (C), and storage (D). Chi-square, Student's test and ANOVA tests were used. p < 0.05 was considered statistically significant. RESULTS: Out of 491 responses, only 9.6% scored above the 75th percentile (19.3% for the general services, 2.4% for dispensing indicator and 12.6% for storage indicator). The main concerns focused on lack of medication and reduced opening hours; however, 67.1% of respondents preferred consulting the community pharmacist instead of visiting primary health care centers, doctor's private clinic and hospitals. Higher mean values of indicators B, C and in the overall indicator were significantly found in the presence of a pharmacist compared to the support pharmacy workforce. CONCLUSION: The overall public perception was inadequate. Significant difference in terms of quality of services was detected in the presence and absence of a community pharmacist during the crisis. It is recommended that the Order of Pharmacist of Lebanon (OPL) and the Ministry of Public Health (MOPH) undergo further steps mainly to enforce the laws concerning dispensing and storage indicators, improve the services in terms of extending the opening hours, ensure the availability of medicines and increase public awareness.

Targeted dendrimeric anticancer prodrug: a methotrexate-folic acid-poly(amidoamine) conjugate and a novel, rapid, "one pot" synthetic approach.

A targeted dendrimeric anticancer prodrug, a conjugate of generation 5 (G5) polyamidoamine (PAMAM) dendrimer, folic acid (FA), and methotrexate (MTX), has been successfully synthesized by using a novel "one pot" approach which is simple, reproducible, and feasible for large-scale synthesis. All dendrimer products have been characterized by (1)H NMR, MALDI-TOF, GPC, and HPLC. With this new method, the ratio of FA versus MTX attached to the dendrimer can be easily tuned to achieve the desired therapeutic effect. A new analytical approach for calculating the numbers of FA and MTX attached to the dendrimer has been established. In vitro studies performed on FA receptor-expressing KB cells show that the new conjugate has a similar affinity and cytotoxic potency to G5-FA-MTX synthesized using the traditional multiple-step approach.

Plasma-mediated release of morphine from synthesized prodrugs.

Two morphine prodrugs ('PDA' and 'PDB') were synthesized and the kinetics of esterase-mediated morphine release from these prodrugs were determined when incubated with plasma from different animal species. Morphine was rapidly released from PDA by all species plasma with the maximum reached within 5-10min; the released morphine was biologically active as determined by an in vitro cAMP assay. The morphine was released from PDB at a slower and species-dependent rate (mouse>rat>guinea pig>human). Morphine's release from PDB appeared to be mediated by carboxyl esterases as the release was inhibited by the carboxyl esterase inhibitor benzil. PDA nor PDB induce cytotoxicity in the neuronal cell lines SK-NSH and SH-SY5Y. The carboxyl and amino functional moieties present on the linker portions of PDA and PDB, respectively, may facilitate their conjugation to nanoparticles to tailor morphine pharmacokinetics and specific targeting. These studies suggest the potential clinical utility of these prodrugs for morphine release at desired rates by administration of their mixture at selected ratios.

Forkhead box M1B is a determinant of rat susceptibility to hepatocarcinogenesis and sustains ERK activity in human HCC.

BACKGROUND AND AIMS: Previous studies indicate unrestrained cell cycle progression in liver lesions from hepatocarcinogenesis-susceptible Fisher 344 (F344) rats and a block of G(1)-S transition in corresponding lesions from resistant Brown Norway (BN) rats. Here, the role of the Forkhead box M1B (FOXM1) gene during hepatocarcinogenesis in both rat models and human hepatocellular carcinoma (HCC) was assessed. METHODS AND RESULTS: Levels of FOXM1 and its targets were determined by immunoprecipitation and real-time PCR analyses in rat and human samples. FOXM1 function was investigated by either FOXM1 silencing or overexpression in human HCC cell lines. Activation of FOXM1 and its targets (Aurora Kinose A, Cdc2, cyclin B1, Nek2) occurred earlier and was most pronounced in liver lesions from F344 than BN rats, leading to the highest number of Cdc2-cyclin B1 complexes (implying the highest G(2)-M transition) in F344 rats. In human HCC, the level of FOXM1 progressively increased from surrounding non-tumorous livers to HCC, reaching the highest levels in tumours with poorer prognosis (as defined by patients' length of survival). Furthermore, expression levels of FOXM1 directly correlated with the proliferation index, genomic instability rate and microvessel density, and inversely with apoptosis. FOXM1 upregulation was due to extracellular signal-regulated kinase (ERK) and glioblastoma-associated oncogene 1 (GLI1) combined activity, and its overexpression resulted in increased proliferation and angiogenesis and reduced apoptosis in human HCC cell lines. Conversely, FOXM1 suppression led to decreased ERK activity, reduced proliferation and angiogenesis, and massive apoptosis of human HCC cell lines. CONCLUSIONS: FOXM1 upregulation is associated with the acquisition of a susceptible phenotype in rats and influences human HCC development and prognosis.

A Rapid Cost Modeling Tool for Evaluating and Improving Public Health Supply Chain Designs.

Effective and efficient health supply chains play a vital role in achieving health outcomes by ensuring supplies are available for people to access quality health services. However, supplying health commodities to service delivery points is complex and costly in many low- and middle-income countries. Thus, governments and partner organizations are often interested in understanding how to design their health supply chains more cost efficiently.Several modeling tools exist in the public and private market that can help assess supply chain efficiency and identify supply chain design improvements. These tools are generally capable of providing users with very precise cost estimates, but they often use proprietary software and require detailed data inputs. This can result in a somewhat lengthy and expensive analysis process, which may be prohibitive for many decision makers, especially in the early stages of a supply chain design process. For many use cases, such as advocacy, informing workshop and technical meetings, and narrowing down initial design options, decision makers may often be willing to trade some detail and accuracy in exchange for quicker and lower-cost analysis results. To our knowledge, there are no publicly available tools focused on generating quick, high-level estimates of the cost and efficiency of different supply chain designs.To address this gap, we designed and tested an Excel-based Rapid Supply Chain Modeling (RSCM) Tool. Our assessment indicated that, despite requiring significantly less data, the RSCM Tool can generate cost estimates that are similar to other common analysis and modeling methods. Furthermore, to better understand how the RSCM Tool aligns with real-world processes and decision-making timelines, we used it to inform an ongoing immunization supply chain redesign in Angola. For the use cases described above we believe that the RSCM Tool addresses an important need for quicker and less expensive ways to identify more cost-efficient supply chain designs.

Follow-up blood cultures are associated with improved outcome of patients with gram-negative bloodstream infections: retrospective observational cohort study.

OBJECTIVES: We examined factors associated with follow-up blood cultures (FUBCs) in patients with monomicrobial Gram-negative (GN) bloodstream infection (BSI) and investigated the impact of FUBCs on therapeutic management and patient outcome. METHODS: A retrospective cohort analysis was conducted of adult patients diagnosed with GN-BSI at a tertiary-care university hospital during 2013-2016. FUBCs performed between 24 hours and 7 days after index BCs was the exposure variable. Risk factors for 30-day mortality were analysed by multivariate Cox analysis on the overall cohort, including FUBCs as a time-varying covariate and on 1:1 matched patients according to Sequential Organ Failure Assessment (SOFA) score and time to FUBC. RESULTS: In 278 (17.6%) of 1576 patients, FUBCs were performed within a median of 3 and 2 days after index BCs and active antibiotic therapy initiation. Persistent BSI was found in 107 (38.5%) of 278 patients. FUBCs were performed in more severely ill patients, with nonurinary sources, difficult-to-treat pathogens and receipt of initial inappropriate therapy. Source control and infectious disease consultation rates were higher among patients with preceding FUBCs and was associated with longer treatment duration. Thirty-day mortality was 10.4%. Independent risk factors for mortality were Charlson comorbidity index (hazard ratio (HR) 1.12) SOFA (HR 1.11), septic shock (HR 2.64), urinary source (HR 0.60), central venous catheter source (HR 2.30), complicated BSI (HR 2.10), carbapenem resistance (HR 2.34), active empiric therapy (HR 0.68), source control (HR 0.34) and FUBCs (HR 0.48). Association between FUBCs and lower mortality was confirmed in the 274 matched pairs. CONCLUSIONS: FUBCs were performed in more severe GN-BSIs, yielding a high rate of persistent BSI. In this context, FUBCs were associated with lower mortality.

CO2 and N2O from water resource recovery facilities: Evaluation of emissions from biological treatment, settling, disinfection, and receiving water body.

Water resource recovery facilities (WRRFs) contribute to climate change and air pollution, as they are anthropogenic potential sources of direct and indirect emission of greenhouse gases (GHGs). Studies concerning the monitoring and accounting for GHG emissions from WRRFs are of increasing interest. In this study, the floating hood technique for gas collection was coupled with the off-gas method to monitor and apportion nitrous oxide (N2O) and carbon dioxide (CO2) emissions from both aerated and non-aerated tanks in a municipal water resource recovery facility, in order to investigate its carbon footprint (CFP). To our knowledge, this is the first time that the chamber technique was applied to evaluate gas fluxes from the settler, where an emission factor (EF) of 4.71 ∗ 10-5 kgCO2,eq kgbCOD-1 was found. Interesting results were found in the disinfection unit, which was the major contributor to direct N2O emissions (with a specific emission factor of 0.008 kgCO2,eq kgbCOD-1), due to the chemical interaction between hydroxylamine and the disinfectant agent (hypochlorite). The specific emission factor of the biological aerated tank was 0.00112 kgCO2,eq kgbCOD-1. The average direct CO2 emission was equal to 0.068 kgCO2 kgbCOD-1 from the activated sludge tank and to 0.00017 kgCO2 kgbCOD-1 from the secondary clarifier. Therefore, taking into account the contribution of both direct N2O and CO2 emissions, values of 0.069 kgCO2,eq kgbCOD-1, 0.008 kgCO2,eq kgbCOD-1 and 0.00022 kgCO2,eq kgbCOD-1, were found for the net CFP of the aerated compartment, the disinfection unit and the clarifier, respectively. The plant energy Footprint (eFP) was also evaluated, confirming that the aeration system is the major contributor to energy consumption, as well as to indirect CO2 emission, with a specific eFP of 1.49 kWh kgbCOD-1.

The impact of carbapenemase-producing Enterobacteriaceae colonization on infection risk after liver transplantation: a prospective observational cohort study.

OBJECTIVE: To investigate the impact of colonization with carbapenemase-producing Enterobacteriaceae (CPE) on the CPE infection risk after liver transplantation (LT). METHODS: Prospective cohort study of all adult patients undergoing LT at our centre over an 8-year period (2010-2017). Individuals were screened for CPE colonization by rectal swabs at inclusion onto the waiting list, immediately before LT and weekly after LT until hospital discharge. Asymptomatic carriers did not receive decolonization, anti-CPE prophylaxis or pre-emptive antibiotic therapy. Participants were followed up for 1 year after LT. RESULTS: We analysed 553 individuals who underwent a first LT, 38 were colonized with CPE at LT and 104 acquired colonization after LT. CPE colonization rates at LT and acquired after LT increased significantly over the study period: incidence rate ratios (IRR) 1.21 (95% CI 1.05-1.39) and 1.17 (95% CI 1.07-1.27), respectively. Overall, 57 patients developed CPE infection within a median of 31 (interquartile range 11-115) days after LT, with an incidence of 3.05 cases per 10 000 LT-recipient-days and a non-significant increase over the study period (IRR 1.11, 95% CI 0.98-1.26). In multivariable analysis, CPE colonization at LT (hazard ratio (HR) 18.50, 95% CI 6.76-50.54) and CPE colonization acquired after LT (HR 16.89, 95% CI 6.95-41.00) were the strongest risk factors for CPE infection, along with combined transplant (HR 2.60, 95% CI 1.20-5.59), higher Model for End-Stage Liver Disease at the time of LT (HR 1.03, 95% CI 1.00-1.07), prolonged mechanical ventilation (HR 2.63, 95% CI 1.48-4.67), re-intervention (HR 2.16, 95% CI 1.21-3.84) and rejection (HR 2.81, 95% CI 1.52-5.21). CONCLUSIONS: CPE colonization at LT or acquired after LT were the strongest predictors of CPE infection. Prevention strategies focused on LT candidates and recipients colonized with CPE should be investigated.

Adherence to international guidelines for the treatment of meningitis infections in Lebanon.

OBJECTIVES: To assess meningitis treatment in Lebanon's compatibility with the Infectious Diseases Society of America (IDSA) guidelines and the effect of non-compliance on mortality. Methods: This is a retrospective study, conducted in 5 Lebanese hospitals, and enrolling all patients diagnosed with meningitis who presented to the involved hospitals from January 2008 to December 2016.  Results: A total of 252 participants were enrolled in the study. Of these patients, 205 (82.7%) were diagnosed with viral meningitis and 47 (17.3%) with bacterial meningitis, which was confirmed using laboratory tests. For patients with viral meningitis, 128 (62.4%) remained on the initial prescribed antibiotics despite the negative cerebrospinal fluid (CSF) and blood culture results. For bacterial meningitis patients, 30.8% received treatment regimen incompatible with the IDSA guidelines. The most common reason for the treatment incompatibility was the definitive drug choice after the culture results (49.1%) and the least common reason was inappropriate hospital stay days (25.9%). The mortality rate was 13.5%. Having low proteins values in the CSF (odds ratio=0.095) was associated with lower mortality compared to patients with normal protein values. Conclusion: This study shows a high percentage of inappropriate treatment in Lebanese hospitals despite these hospitals having adopted international treatment guidelines. This inappropriate management was associated with an increasing rate of mortality and neurological complications.