Sewer System Alternatives Evaluation for Potential Creswell Area Expansion in Harford County

Final project for ENCE422: Project Cost Accounting and Economics (Fall 2018). University of Maryland, College Park.This report summarizes the findings of the ENCE422 Fall 2018 class term project. Students were tasked with evaluating sewer system alternatives for the Creswell area expansion in Harford County. Student groups were to consider environmental impacts, community/social impacts, and perform financial analysis for the alternatives they chose to evaluate. This report extracts information from 14 separate team presentations and synthesizes it around the following structure; 1. Systems that Utilize Septic Tanks a. Traditional Septic System b. Orenco Effluent System c. Small Diameter Gravity Sewer System 2. System that Do Not Utilize Septic Tanks a. Traditional Gravity System b. Vacuum System c. Grinder Pump SystemHarford Count

Biocidal Cationic Macromolecules Irrespective of Bacterial Resistance: Our Best Achievements

Since new antibacterial agents against multi-drug resistant (MDR) bacteria are urgently needed, we recently synthetized cationic dendrimers and copolymers and assessed their antibacterial activity on numerous MDR clinical isolates. Being cationic, the prepared macromolecules electrostatically interacted with pathogens’ surfaces, causing irreversible damages and rapid bacterial death. A lysine dendrimer having 192 cationic groups (N+) was strongly active preferentially on non-fermenting Gram-negative species, displaying MICs comparable to colistin against P. aeruginosa (2.1 µM). A lysine dendrimer (128 N+) was explicitly active on Acinetobacter, while a cationic copolymer showed remarkable antibacterial activity against numerous Gram-positive and Gram-negative species. In 24 h-time-killing experiments, all of the mentioned macromolecules displayed rapid bactericidal effects, while when tested on human keratinocytes, especially G5-PDK, showed low levels of cytotoxicity and high values of selectivity indices. Due to their physicochemical properties and bactericidal potency, the herein reviewed cationic macromolecules could represent novel tools for realizing either a targeted or a broad-spectrum bactericidal action, regardless of the bacterial resistance to current antibiotics

Biocidal Cationic Macromolecules Irrespective of Bacterial Resistance: Our Best Achievements

The global emerging infectious diseases caused by multi-drug resistant (MDR) bacteria necessitates worldwide systematic efforts to discover new effective antibacterial agents, replacing traditional antibiotics no longer active. For this purpose, we recently synthetized amino acid-modified cationic dendrimers and ammonium hydrochloride copolymers and evaluated their antibacterial activity on several MDR clinical isolates. As natural antibacterial peptides (AMPs), the prepared cationic macromolecules were capable to electrostatically interact with the membranes of pathogens, causing irreversible damage and inhibition of bacterial growth, regardless of their resistance to most conventional antibiotics. The dendrimers, depending on their amino acid composition, the number of cationic groups and the structure of the internal matrix, showed a target specific antibacterial activity. Indeed, those containing lysine and/or histidine, having 192 cationic groups (N+), were active on non-fermenting Gram-negative species. In particular, the G5K dendrimer showed a very low MIC value on P. aeruginosa (2.1 \ub5M), comparable to that of colistin. The arginine and/or lysine dendrimers with 70-136 N+ were specifically active on Enterococci and Staphylococci, while the lysine dendrimer, with 128 N+, based on the results obtained so far, is active on Acinetobacter (6.3-12.7 \ub5M). Unlike the dendrimers, the copolymers showed MICs as low as 0.6-1.2 \ub5M against several Gram-positive and Gram-negative isolates. In this communication review, we examined the preparation and antibacterial effects of the best performing cationic macromolecules mentioned above. In turbidimetric and 24 hour-killing studies, both the dendrimers and copolymers here examined displayed a rapid bactericidal activity. Thanks to their physicochemical properties, suitable for biomedical applications, and to the observed bactericidal effects, our new cationic dendrimers and copolymers could represent novel tools, with narrow and/or broad-spectrum activity against MDR strains, regardless of their resistance to current antibiotics

Biocidal Cationic Macromolecules Irrespective of Bacterial Resistance: Our Best Achievements (Our Ongoing Studies)

Difficult-to-treat bacterial infections involving resistant human and plant pathogens, severely afflict hospitals and concern the agri-food sector. Bacteria of the genus Pseudomonas can quickly become resistant to antibiotics and spread such resistance to other bacteria. Species such as P. aeruginosa, P. putida and P. fluorescens, which normally produce antibiotics or help reduce some forms of pollution, can trigger serious nosocomial infections in humans. P. fragi is a major cause of dairy and meat spoilage, while P. syringae can infect a wide range of economically important plant species, including tobacco, kiwi and tomato. Therefore, new strategies and antibacterial agents capable of stopping these bacteria, regardless of their resistance to antibiotics, are urgently needed to limit serious human infections, food waste, plantation extermination and economic losses

Virulence Factors in Urinary Escherichia coli Strains: Phylogenetic Background and Quinolone and Fluoroquinolone Resistance▿

Quinolone- and fluoroquinolone-resistant Escherichia coli strains harbor fewer virulence factors than susceptible strains. The reasons underlying this correlation are incompletely understood. We investigated the phylogenetic background, the presence of the papC, hlyA, and cnf1 (pathogenicity island IIJ96-associated), fimA, iss, and iutA genes, and the presence of type 1 fimbriae, P fimbriae, and hemolysin in 243 urinary E. coli isolates resistant only to quinolones (8%), resistant to both quinolones and fluoroquinolones (51%), or susceptible to both drugs (41%). Group B2 accounted for 56% of the isolates, showing a significantly higher prevalence among fluoroquinolone-susceptible strains than among resistant strains (65% versus 50% [P = 0.03]). hly and cnf1 were significantly more associated with susceptibility (P < 0.001) and with group B2 (P < 0.001 for group B2 versus groups A and D). However, within group B2, fluoroquinolone-resistant strains showed lower prevalences of papC, hlyA, and cnf1 than their susceptible counterparts (P < 0.001). In contrast, the incidence of iutA appeared higher for refractory isolates, including group B2, than for susceptible isolates (P < 0.001). Only in group B2 did fluoroquinolone-resistant strains reveal a lesser ability to agglutinate Saccharomyces cerevisiae (7%) than quinolone-resistant (87%) and susceptible (80%) isolates, despite uniform possession of fimA genes. No similar contrast emerged for expression of hemolysin and P fimbriae. Mutations conferring quinolone and fluoroquinolone resistance may thus require a particular genetic background, not strictly correlated with phylogenetic groups. More interestingly, the mutational event itself can affect the expression of type 1 fimbriae, at least in the prevalent and complex B2 strains

Synthesis, Characterization, and Bactericidal Activity of a 4-Ammoniumbuthylstyrene-Based Random Copolymer

The growing resistance of bacteria to current chemotherapy is a global concern that urgently requires new and effective antimicrobial agents, aimed at curing untreatable infection, reducing unacceptable healthcare costs and human mortality. Cationic polymers, that mimic antimicrobial cationic peptides, represent promising broad-spectrum agents, being less susceptible to develop resistance than low molecular weight antibiotics. We, thus, designed, and herein report, the synthesis and physicochemical characterization of a water-soluble cationic copolymer (P5), obtained by copolymerizing the laboratory-made monomer 4-ammoniumbuthylstyrene hydrochloride with di-methyl-acrylamide as uncharged diluent. The antibacterial activity of P5 was assessed against several multi-drug-resistant clinical isolates of both Gram-positive and Gram-negative species. Except for strains characterized by modifications of the membrane charge, most of the tested isolates were sensible to the new molecule. P5 showed remarkable antibacterial activity against several isolates of genera Enterococcus, Staphylococcus, Pseudomonas, Klebsiella, and against Escherichia coli, Acinetobacter baumannii and Stenotrophomonas maltophilia, displaying a minimum MIC value of 3.15 \ub5M. In time-killing and turbidimetric studies, P5 displayed a rapid non-lytic bactericidal activity. Due to its water-solubility and wide bactericidal spectrum, P5 could represent a promising novel agent capable of overcoming severe infections sustained by bacteria resistant the presently available antibiotics

A Highly Efficient Polystyrene-Based Cationic Resin to Reduce Bacterial Contaminations in Water

Nowadays, new water disinfection materials attract a lot of attention for their cost-saving and ease of application. Nevertheless, the poor durability of the matrices and the loss of physically incorporated or chemically attached antibacterial agents that can occur during water purification processes considerably limit their prolonged use. In this study, a polystyrene-based cationic resin (R4) with intrinsic broad-spectrum antibacterial effects was produced without needing to be enriched with additional antibacterial agents that could detach during use. Particularly, R4 was achieved by copolymerizing 4-ammonium-butyl-styrene (4-ABSTY) with N,N-dimethylacrylamide (DMAA) and using N-(2-acryloylamino-ethyl)-acrylamide (AAEA) as a cross-linker. The R4 obtained showed a spherical morphology, micro-dimensioned particles, high hydrophilicity, high-level porosity, and excellent swelling capabilities. Additionally, the swollen R4 to its maximum swelling capability, when dried with gentle heating for 3 h, released water following the Higuchi’s kinetics, thus returning to the original structure. In time–kill experiments on the clinical isolates of multidrug-resistant (MDR) pathogens of fecal origin, such as enterococci, Group B Salmonella species, and Escherichia coli, R4 showed rapid bactericidal effects on enterococci and Salmonella, and reduced E. coli viable cells by 99.8% after 4 h. When aqueous samples artificially infected by a mixture of the same bacteria of fecal origin were exposed for different times to R4 in a column, simulating a water purification system, 4 h of contact was sufficient for R4 to show the best bacterial killing efficiency of 99%. Overall, thanks to its physicochemical properties, killing efficiency, low costs of production, and scalability, R4 could become a cost-effective material for building systems to effectively reduce bacterial, even polymicrobial, water contamination

Efficacy of Ursolic Acid-Enriched Water-Soluble and Not Cytotoxic Nanoparticles against Enterococci

none8Ursolic acid (UA), a pentacyclic triterpenoid acid found in many medicinal plants and aromas, is known for its antibacterial effects against multi-drug-resistant (MDR) Gram-positive bacteria, which seriously threaten human health. Unfortunately, UA water-insolubility, low bioavailability, and systemic toxicity limit the possibilities of its application in vivo. Consequently, the beneficial activities of UA observed in vitro lose their potential clinical relevance unless water-soluble, not cytotoxic UA formulations are developed. With a nano-technologic approach, we have recently prepared water-soluble UA-loaded dendrimer nanoparticles (UA-G4K NPs) non-cytotoxic on HeLa cells, with promising physicochemical properties for their clinical applications. In this work, with the aim of developing a new antibacterial agent based on UA, UA-G4K has been tested on different strains of the Enterococcus genus, including marine isolates, toward which UA-G4K has shown minimum inhibitory concentrations (MICs) very low (0.5–4.3 µM), regardless of their resistance to antibiotics. Time-kill experiments, in addition to confirming the previously reported bactericidal activity of UA against E. faecium, also established it for UA-G4K. Furthermore, cytotoxicity experiments on human keratinocytes revealed that nanomanipulation of UA significantly reduced the cytotoxicity of UA, providing UA-G4K NPs with very high LD50 (96.4 µM) and selectivity indices, which were in the range 22.4–192.8, depending on the enterococcal strain tested. Due to its physicochemical and biological properties, UA-G4K could be seriously evaluated as a novel oral-administrable therapeutic option for tackling difficult-to-treat enterococcal infections.openSchito, Anna Maria; Caviglia, Debora; Piatti, Gabriella; Zorzoli, Alessia; Marimpietri, Danilo; Zuccari, Guendalina; Schito, Gian Carlo; Alfei, SilvanaSchito, Anna Maria; Caviglia, Debora; Piatti, Gabriella; Zorzoli, Alessia; Marimpietri, Danilo; Zuccari, Guendalina; Schito, Gian Carlo; Alfei, Silvan

Broad-Spectrum Bactericidal Activity of a Synthetic Random Copolymer Based on 2-Methoxy-6-(4-Vinylbenzyloxy)-Benzylammonium Hydrochloride

Low-molecular-weight organic ammonium salts exert excellent antimicrobial effects by interacting lethally with bacterial membranes. Unfortunately, short-term functionality and high toxicity limit their clinical application. On the contrary, the equivalent macromolecular ammonium salts, derived from the polymerization of monomeric ammonium salts, have demonstrated improved antibacterial potency, a lower tendency to develop resistance, higher stability, long-term activity, and reduced toxicity. A water-soluble non-quaternary copolymeric ammonium salt (P7) was herein synthetized by copolymerizing 2-methoxy-6-(4-vinylbenzyloxy)-benzylammonium hydrochloride monomer with N, N-di-methyl-acrylamide. The antibacterial activity of P7 was assessed against several multidrug-resistant (MDR) clinical isolates of both Gram-positive and Gram-negative species. Except for colistin-resistant Pseudomonas aeruginosa, most isolates were susceptible to P7, also including some Gram-negative bacteria with a modified charge in the external membrane. P7 showed remarkable antibacterial activity against isolates of Enterococcus, Staphylococcus, Acinetobacter, and Pseudomonas, and on different strains of Escherichia coli and Stenotrophomonas maltophylia, regardless of their antibiotic resistance. The lowest minimal inhibitory concentrations (MICs) observed were 0.6\u20131.2 \ub5M and the minimal bactericidal concentrations (MBC) were frequently overlapping with the MICs. In 24-h time\u2013kill and turbidimetric studies, P7 displayed a rapid non-lytic bactericidal activity. P7 could therefore represent a novel and potent tool capable of counteracting infections sustained by several bacteria that are resistant to the presently available antibiotics

ATTIVITA\u2019 ANTIBATTERICA DI FRUTTICULINA A E DEMETILFRUTTICULINA AESTRATTI DA SALVIA CORRUGATA VAHL.

Frutticulina-A (FA) e Demetilfrutticulina-A (dFA), estratte da S.corrugata, sono state saggiate su batteri patogeni umani, anche multi-resistenti agli attuali farmaci antibiotici. Le due molecole sono risultate particolarmente attive nei confronti di batteri Gram-positivi come Staphylococcus aureus, S.epidermidis, Enterococcus faecium e E. faecalis, nei confronti dei quali hanno dimostrato capacit\ue0 batteriostatiche o battericide. Entrambe le sostanze hanno inoltre rivelato di possedere una interessante capacit\ue0 di inibire \u201cin vitro\u201d la formazione di biofilm da parte di vitro S.aureus, S. epidermidis e E.faecalis. FA e dFA sembrano essere nuovi e promettenti composti da valutare per un possibile uso nei confronti di importanti batteri patogeni umani, anche responsabili di infezioni in cui la presenza di biofilm gioca un ruolo fondamentale