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Since 1997, Chubu Rosai Hospital has been establishing the proper use of various antibacterial drugs through the activities of an infection control team (ICT), introduction of a notification system for specific antibacterial drug use, and intervention of ward pharmacists for individual cases. There is no infectious disease department, and we have been working closely with each other on multiple occupations. As an initiative, we established the Nagoya Southern Infection Countermeasures Meeting in 2006 and conducted antimicrobial use and resistance (AUR) surveys to promote the proper use of antimicrobial agents within the area. In April 2018, we formed an antimicrobial stewardship team (AST) and initiated activities. In addition, an AST pharmacist can share the AST results with the ward pharmacist, for proper use of antibacterial drugs and for early monitoring of infectious disease treatment and appropriate intervention, thus improving the efficiency of the ward pharmacist's work. This program will also lead to the development of training programs for the younger generation of pharmacists.

Introduction Berberine (BBR), as one of the outstanding representatives of isoquinoline alkaloids, has been used as an antibacterial drug for a long time in China since ancient times. Currently, a large number of studies have been reported that berberine has a wide spectrum of pharmacological activities, such as anti-tumor, anti-inflammatory, hypoglycemic, hypolipidemic, anti-obesity, and the like. Areas covered This review systematically discussed important patents on berberine and berberine derivatives in terms of pharmacological activity between 2016 and 2020. These patents were mainly searched through the European Patent Office database and Web of Science. These berberine patents (~41) cover a wide range of applications, mainly including antitumor, anti-inflammatory, antibacterial, anti-metabolic disorder, and other newly reported pharmacological activities. Expert opinion Berberine is an important lead compound with great potential for optimization in drug development. However, there is a lack of research related to the biomolecular targets of BBR, which directly restricts the development of berberine in the pharmaceutical field. The problems involved with poor bioavailability and cytotoxicity are also worth considering in the development of berberine-based drugs. Accordingly, the increasing number of patents involving biomolecular targets in BBR's patent applications will be published as its related pharmacological mechanisms are further deciphered.

Background An antibacterial drug’s susceptibility test interpretive criteria (STIC) are determined by integrating clinical, microbiological and pharmacokinetic-pharmacodynamic (PK-PD) data. PTA analysis plays a pivotal or supportive role in STIC determination and is heavily dependent on the PK-PD target values determined from animal PK-PD studies. Therefore, variations in PK-PD target values may impact STIC determination. Factors contributing to variation in the PK-PD target values include the number of and MICs for bacterial isolates used in animal PK-PD studies. Objectives To analyse the relationship between PK-PD target values and MICs, describe the variations in PK-PD target values of isolates and evaluate whether the proposed/target STICs were within the ranges of the MICs for isolates used in animal PK-PD studies. Methods A database was compiled for this research by screening animal PK-PD study reports submitted to the FDA from 10 new drug applications (NDAs). Results A relationship evaluation between PK-PD target values and MICs for tested isolates for seven drugs (that used AUC/MIC ratio as the PK-PD index) showed that, generally, the AUC/MIC values decreased with an increase in MIC. These target values were highly variable, with the percentage coefficient of variation ranging between 1% and 132% for isolates having the same MIC. For 16/27 (59%) drug/bacteria combinations from all 10 drugs, the proposed/target STICs were higher than the highest MIC for bacteria isolates evaluated, while 6/27 (22.5%) were lower. Conclusions This research suggests that careful considerations related to selection of bacterial isolates for animal PK-PD studies could strengthen the STIC determination process.

Multidrug-resistant bacterial infections have become an important cause of clinical death in the twenty-first century. Much effort has been made to overcome this challenge. The discovery of novel antimicrobial compounds, as well as the rational use of antibacterial drugs with different structure types and mechanisms, is helping to deal with bacterial resistance. Currently, pyrimidine-containing agents are the major areas of new antibacterial drug discovery. Given their good activities and diverse mechanisms of action, many pyrimidine-containing heterocyclic compounds have become the focus of interest for many scientists. In addition, pyrimidine structure is an important part of many endogenous substances, which is an advantage that allows pyrimidine derivatives to interact with genetic materials, enzymes and other biopolymeric substances in the cell. Scientists have focused on the discovery and structural optimization of pyrimidine derivatives, which has resulted in the discovery of many novel pyrimidine derivatives with intriguing profiles. Herein we summarize the therapeutic potentials of pyrimidine compounds that are promising for antimicrobial applications over the last decade. In particular, the relationships between the structures of modified pyrimidines and their antimicrobial activity are systematically discussed.

Antibiotic resistance is one of the most relevant problems nowadays. The effectiveness of antibiotic therapy is determined, among other things, by the pharmacokinetic characteristics of the antibacterial drug. Therapeutic drug monitoring (TDM) is a modern way of overcoming the resistance of pathogens found in hospitals, which allows individualizing doses of the drug, especially in com­plex cases with increased pathogen resistance. The article describes two clinical cases of prescribing meropenem and conducting TDM, which made it possible to individualize the dosage of the antibacterial drug and provide adequate and effective therapy to patients. In the described clinical cases, the proposed dosing regimen of meropenem allowed achieving the target values of % T> MIC — more than 40%.

Emergence of drug resistance has created unmet medical need for the development of new classes of antibiotics. Discovery of new antibacterial agents with new mode of action remains a high priority universally. 4(3H)-quinazolinone, a fused nitrogen heterocyclic compound has emerged as a biologically privileged structure, possessing a wide range of biological properties viz. anticancer, antibacterial, antitubercular, antifungal, anti-HIV, anticonvulsant, anti-inflammatory and analgesic activities. Promising antibacterial properties of quinazolinones have enthused the medicinal chemists to explore and develop this fused heterocyclic system for new antibacterial agents. Utilization of quinazolinone core for the design and synthesis of new antibacterial agents has recently gained momentum. This review aims to provide an overview of the structures and antibacterial activity of various 4(3H)-quinazolinone derivatives covering various aspects of in vitro and in vivo pharmacological activities and structure activity relationships (SARs).

The widespread use of antibiotics has made the problem of bacterial resistance increasingly serious, and the study of new drug-resistant bacteria has become the main direction of antibacterial drug research. Among antibiotics, the fully synthetic oxazolidinone antibacterial drugs linezolid and tedizolid have been successfully marketed and have achieved good clinical treatment effects. Oxazolidinone antibacterial drugs have good pharmacokinetic and pharmacodynamic characteristics and unique antibacterial mechanisms, and resistant bacteria are sensitive to them. This Perspective focuses on reviewing oxazolidinones based on the structural modification of linezolid and new potential oxazolidinone drugs in the past 10 years, mainly describing their structure, antibacterial activity, safety, druggability, and so on, and discusses their structure-activity relationships, providing insight into the reasonable design of safer and more potent oxazolidinone antibacterial drugs.

Exebacase (CF-301) belongs to a new class of protein-based antibacterial agents, known as lysins (peptidoglycan hydrolases). Exebacase, a novel lysin with antistaphylococcal activity, is in phase 3 of clinical development. To advance into the clinic, it was necessary to develop an accurate and reproducible method for exebacase MIC determination. The Clinical and Laboratory Standards Institute (CLSI) reference broth microdilution (BMD) method using cation-adjusted Mueller-Hinton broth (CAMHB) produced trailing MIC endpoints, and exebacase activity was diminished when frozen BMD panels were used. A modified BMD method was developed using CAMHB supplemented with 25% horse serum and 0.5 mM dl-dithiothreitol (CAMHB-HSD). Preliminary quality control (QC) ranges for Staphylococcus aureus ATCC 29213 of 0.25 to 1 μg/ml and for Enterococcus faecalis ATCC 29212 of 16 to 64 μg/ml were determined based on the results of a CLSI M23-defined MIC QC tier 1 study. These preliminary QC ranges validated the MIC data generated from a systematic study testing a discrete S. aureus strain collection using CAMHB-HSD to investigate the impact of parameters known to influence susceptibility test results and to evaluate the exebacase MIC distribution against clinical S. aureus isolates. Presentation of these data led to the CLSI Subcommittee on Antimicrobial Susceptibility Testing (AST) approval of the use of CAMHB-HSD to determine exebacase susceptibility and commencement of a multilaboratory (tier 2) QC study. Use of a standard BMD method and concomitant QC testing provides confidence in the assessment of test performance to generate accurate and reproducible susceptibility data during antibacterial drug development.

The U.S. Food and Drug Administration (FDA) hosted a public workshop entitled “Advancing Animal Models for Antibacterial Drug Development” on 5 March 2020. The workshop mainly focused on models of pneumonia caused by Pseudomonas aeruginosa and Acinetobacter baumannii . The program included discussions from academic investigators, industry, and U.S. government scientists. The potential use of mouse, rabbit, and pig models for antibacterial drug development was presented and discussed.

Azo molecules possess the characteristic azo bond (-N=N-) and are considered fascinating motifs in organic chemistry. Since the last century, these brightly colored compounds have been widely employed as dyes across several industries in applications for printing, food, paper, cosmetics, lasers, electronics, optics, material sciences, etc. The discovery of Prontosil, an antibacterial drug, propelled azo compounds into the limelight in the field of medicinal chemistry. Subsequent discoveries including Phenazopyridine, Basalazide, and Sulfasalazine enabled azo compounds to occupy a significant role in the drug market. Furthermore, azo compounds have been employed as antibacterial, antimalarial, antifungal, antioxidant, as well as antiviral agents. The metabolic degradation of many azo dyes can induce liver problems if ingested, posing a safety concern and limiting their application as azo dyes in medicinal chemistry. However, azo dyes remain particularly significant for applications in cancer chemotherapy. Recently, a paradigm shift has been observed in the use of azo dyes: from medicinal chemistry to biomedical sciences. The latter benefits from azo dye application are related to imaging, drug delivery, photo-pharmacology and photo switching. Herein, we have compiled and discussed recent works on azo dye compounds obtained so far, focusing on their medicinal importance and future prospects.

The rational use of antibacterial drugs in children implies an adequate choice of the necessary medication, its dosing regimen, and the duration of treatment in order to achieve maximum efficacy and minimize toxic effects. The knowledge of pharmacokinetic and pharmacodynamic profiles of the antibacterial drug plays a crucial role for optimizing the dosing regimen. The strategy of individual choice of the dosing regimen, taking into account the principles of pharmacokinetics and pharmacodynamics, can be especially effective in patients with the expectedly changed parameters of pharmacokinetics and in infections caused by bacteria strains with low sensitivity to antibiotics. The review presents a contemporary view of pharmacokinetic and pharmacodynamic profiles of antibacterial drugs most commonly used in pediatrics and their relationship to the clinical efficacy of the administered therapy.

ENABLE is an antibacterial drug discovery and development consortium formed as a public–private partnership in 2014 as part of the Innovative Medicines Initiative (IMI) New Drugs for Bad Bugs (ND4BB) programme. With the project soon ending, here we provide a brief overview and reflect on its achievements, strengths and weaknesses. ENABLE is an antibacterial drug discovery and development consortium formed as a public–private partnership in 2014 as part of the Innovative Medicines Initiative (IMI) New Drugs for Bad Bugs (ND4BB) programme. With the project soon ending, here we provide a brief overview and reflect on its achievements, strengths and weaknesses.

Richard H Ebright talks to Rachel Coleby, Commissioning Editor: Ebright is at Rutgers University (New Brunswick, NJ, USA), where he performs research on the structure, mechanism, and regulation of bacterial transcription and on antibacterial drug discovery targeting bacterial transcription. He has received research awards, including the Searle Scholar Award, the Walter J Johnson Prize, the Schering-Plough Award of the American Society for Biochemistry and Molecular Biology, the Waksman Award of the Theobold Smith Society, the MERIT Award of the National Institutes of Health, and membership in the American Academy of Arts and Science. He has more than 130 publications in peer-reviewed journals and more than 30 issued and pending patents.

My thesis is a simple one. We have not been doing a good enough job selecting dose regimens for serious infections during the drug development process. If we are to do a better job in the future, we need to revisit some uncomfortable places. That is, some notable program failures. To be clear, we are not revisiting program failures to make anyone uncomfortable or cast aspersions - but rather so that we sow the seeds for a better future. To that end, we will examine program failures and successes through a pharmacometric lens. Through this powerful lens, we will come to understand that many of our failures were not only predictable, but perhaps expected and entirely avoidable. The goal of this communication is to set forth the type of thinking and data that is necessary for rational dose selection.

INTRODUCTION: Drug conjugates are trend topics in Chemical Biology. These entities are an emerging class of highly potent biopharmaceutical drugs, best known in the field of oncology, that have been also designed as a targeted therapy/diagnosis for the treatment/prevention of several bacterial diseases. Antibiotic resistance is now a major threat to public health, and targeted strategies can reduce resistance. The following review aims at giving an overview of the patented therapeutic innovations covering these areas. Particular attention has been given to antibacterial drug conjugates in the last 30 years. AREAS COVERED: The authors provide an overview of the scientific reports describing the research and development of new drug conjugates for bacterial diseases. The review emphasizes the rationale behind synthesis, biological activities and improvement of the new drug conjugates. New technologies applied for the research in this field have also been discussed. The article is based on the most relevant literature related to the development of new therapeutic solutions. The patents presented in this review have been collected from multiple electronic databases including SciFinder, Pubmed, Espacenet and Mendeley. EXPERT OPINION: The new drug conjugates described in the current review proved to display improved delivery, efficacy, targeting abilities and fewer side effects. Versatile approaches were invented to achieve these goals.

Bacterial infections remain the leading cause of death in children, the elderly, and immunocompromised patients. Andrographolide (AG), the main active component of the herb Andrographis paniculata, has been used for many years for anti-inflammatory and antibacterial infections. AG has an antibacterial effect on a wide variety of bacteria, which is reflected in the inhibition of bacterial pathogenic factors and the regulation of immunity to downregulate infectious inflammation caused by bacteria. In the current climate of frequently occurring antibiotic resistance, AG might be considered a promising lead for new antibacterial drug development. This review outlines the therapeutic potential of AG and its analogs in combating various bacterial infections, focusing on the mechanisms of action.

BACKGROUND Previous studies have described drug shortages; however, there has been no comprehensive evaluation focusing on US antibacterial shortages. METHODS Drug shortage data from the University of Utah Drug Information Service database were analyzed, with a focus on antibacterial agents from 2001 to 2013. We used descriptive statistics to describe trends in drug shortages, analyze drug classes commonly affected, and investigate whether drugs experienced multiple periods of shortages. RESULTS One hundred forty-eight antibacterial drugs were on shortage over the 13-year study period, with 26 drugs still active on shortage as of December 2013. The median number of new shortages per year was 10 (interquartile range [IQR], 7). The number of drugs on shortage increased at a rate of 0.35 additional drugs every month (95% confidence interval, .22-.49) from July 2007 to December 2013 (P < .001). The median shortage duration was 188 days (IQR, 366.5). Twenty-two percent of drugs experienced multiple shortage periods. CONCLUSIONS There were a substantial number of drug shortages from 2001 to 2013, with a dramatic rise in shortages since 2007. Shortages of agents used to treat multidrug-resistant infections are of concern due to continued transmission and limited treatment options.

Revisiting unexploited antibiotics in search of new antibacterial drug candidates: the case of MSD-819 (6-chloro-2-quinoxalinecarboxylic acid 1,4-dioxide)

An urgent need exists to develop new antibacterial drugs for children. We conducted research with investigators of pediatric antibacterial drug trials to identify facilitators and barriers in the conduct of these trials. Seventy-three investigators completed an online survey assessing the importance of 15 facilitators (grouped in 5 topical categories) and the severity of 36 barriers (grouped in 6 topical categories) to implementing pediatric antibacterial drug trials. Analysis focused on the identification of key factors that facilitate the successful implementation of pediatric antibacterial drug trials and the key barriers to implementation. Almost all investigators identified two factors as very important facilitators: having site personnel for enrollment and having adequate funding. Other top factors were related to staffing. Among the barriers, factors related to parent concerns and consent were prominent, particularly obtaining parental consent when there was disagreement between parents, concerns about the number of blood draws, and concerns about the number of invasive procedures. Having overly narrow eligibility criteria was also identified as a major barrier. The survey findings suggest three areas in which to focus efforts to help facilitate ongoing drug development: (1) improving engagement with parents of children who may be eligible to enroll in a pediatric antibacterial drug trial, (2) broadening inclusion criteria to allow more participants to enroll, and (3) ensuring adequate staffing and establishing sustainable financial strategies, such as funding pediatric trial networks. The pediatric antibacterial drug trials enterprise is likely to benefit from focused efforts by all stakeholders to remove barriers and enhance facilitation.

Cephalosporins are the most important antibiotics having β-lactam ring and are obtained from a fungus Acremonium, also known as cephalosporium. The wide use of cephalosporins against bacteria in various severe infections such as respiratory tract infection (RTI), skin infection and urinary tract infection (UTI) has led the scientist dive into the detail of this antibacterial drug. The knowledge about structural activity relationship (SAR), spectrum of inhibition (SOI), chemical properties and pharmacology of cephalosporin has pivotal impact to device advanced therapeutic results. The treatment of a disease using cephalosporin has many pros and cons. If the pharmacology and chemical properties of this drug are known properly, many side effects can be diminished or minimized to a certain level. This article review some pharmacological and chemical properties of cephalosporins.

Correction for ‘Cyrene™ is a green alternative to DMSO as a solvent for antibacterial drug discovery against ESKAPE pathogens’ by Jason E. Camp et al., RSC Med. Chem., 2020, 11, 111–117.

One of the main promising directions in the development of pharmacology is the development of drugs that provide targeted drug concentration and effective approaches to obtaining them using nanoscale drug delivery systems. In our opinion, the most promising is the use of biodegradable delivery systems due to their low toxicity and xenobiotic effects on the patient’s body. The need to develop regulated drug delivery systems is due to their clear advantage over analogues in standardized dosage forms. Based on modern research publications we have developed an exosomal antibacterial form of azithromycin that has pronounced selective properties for respiratory epithelial cells. The aim of the work was to study the safety parameters of the developed drug based on exosomal particles, in particular subchronic toxicity. For the study 3 experimental and 1 control groups of white rats weighing 190-220 g were formed with 10 heads each. The drug was administered intragastrically daily for 90 days in doses of 1/10; 1/20 and 1/50 of the LD50 set in the acute experiment. The study found that the use of the developed exosomal drug intragastrically once a day for 90 days does not affect the behavioral responses of animals and their external condition.

Peptide deformylase (PDF) is a class of metalloenzyme responsible for catalyzing the removal of the N-formyl group from N-terminal methionine following translation. PDF inhibitors are moving into new phase of drug development. Initially, PDF was considered as an important target in antibacterial drug discovery; however genome database searches have revealed PDF-like sequences in parasites (P. falciparum) and human, widening the utility of this target in antimalarial and anticancer drug discovery along with antibacterial. Using structural and mechanistic information together with high throughput screening, several types of chemical classes of PDF inhibitors with improved efficacy and specificity have been identified. Various drugs like, GSK-1322322 (Phase II), BB-83698 (Phase I), and LBM-415 (Phase I) have entered into clinical developments. Developments in the field have prompted us to review the current aspects of PDFs, especially their structures, different classes of PDF inhibitors, and molecular modeling studies. In nut shell, this review enlightens PDF as a versatile target along with its inhibitors and future perspectives of different PDF inhibitors.

Oritavancin (Orbactiv(®)) is a lipoglycopeptide antibacterial drug with activity against Gram-positive bacteria developed by The Medicines Company as a single-dose treatment for acute bacterial skin and skin structure infections (ABSSSI). The drug received its first global approval for this indication in the US in August 2014, and is under regulatory review in the EU. This article summarises the milestones in the development of oritavancin leading to this first approval for the treatment of ABSSSIs caused by Gram-positive bacteria.

Antibacterial drug discovery is moving from largely unproductive high-throughput screening of isolated targets in the past decade to revisiting old, clinically validated targets and drugs, and to classical black-box whole-cell screens. At the same time, due to the application of existing methods and the emergence of new high-throughput biology methods, we observe the generation of unprecedented qualities and quantities of genomic and other omics data on bacteria and their physiology. Tuberculosis (TB) drug discovery and biology follow the same pattern. There is a clear need to reconnect antibacterial drug discovery with modern, genome-based biology to enable the identification of new targets with high confidence for the rational discovery of new drugs. To exploit the increasing amount of bacterial biology information, a variety of in silico methods have been developed and applied to large-scale biological models to identify candidate antibacterial targets. Here, we review key concepts in network analysis for target discovery in tuberculosis and provide a summary of potential TB drug targets identified by the individual methods. We also discuss current developments and future prospects for the application of systems biology in the field of TB target discovery.

In concert with improvements in personal hygiene and public sanitation, the discovery and development of antibiotics during the latter half of the last century has reduced substantially the morbidity and mortality associated with bacterial diseases. However, the past decade has witnessed a sharp reduction in interest in antibacterial drug development by 'big pharma', compounded by a decline in the breadth of chemical space for new antibacterial molecules and a failure to exploit the plethora of cellular processes potentially targetable by novel classes of antibacterial molecules. This review focuses on some strategies relating to antibacterial chemotherapy, paths less trodden, which the author considers worthy of further exploration.

A new series of indole appended dihydronaphthalenone hybrid analogues (5a-t) have been synthesized through the Lewis acid catalyzed Michael addition of indoles to the arylidene/hetero arylidene ketones. All the synthesized derivatives are well characterized through the 1H-NMR, 13C-NMR, HRMS spectroscopic techniques, compound 5r was further confirmed through single crystal X-ray analysis and screened for antibacterial and anti-tubercular activities. Among the synthesized compounds, the minimum inhibition concentration of 5l (against E.coli) and 5o & 5p (against E.coli & S.aureus) was found to be as low as 3.12 μgmL−1 as compared to the standard antibacterial drug Ciprofloxacin 2.5 μgmL−1. In anti-tubercular activity, compound 5o and 5p with minimum inhibition concentration 6.25 μgmL−1 was found to be comparable with that of the drugs Pyrazinamide 5 μgmL−1 and Streptomycin 5 μgmL−1. Compounds 5i, 5j, 5m, 5n, 5q and 5r also showed promising activity against group of organisms tested. This article is protected by copyright. All rights reserved.

Background The WHO/ATC (Anatomical Therapeutic Chemical) index DDD (WHO-DDD) is commonly used for drug consumption measurement. Discrepancies between WHO-DDD and actual prescribed daily doses (PDD) in hospitals have prompted alternative dose definitions adapted to doses recommended in hospital practice guidelines [recommended daily doses (RDD)]. Methods In order to validate RDD we performed modified point prevalence surveys in 24 acute care hospitals and recorded 20620 PDD of antibiotics given to 4226 adult patients on the day of the survey and the 6 preceding days. We calculated RDD and WHO-DDD and compared them with PDD. Results The rate of RDD corresponding to PDD was higher than the corresponding rate for WHO-DDD (pooled data, 55% versus 30%) and the differences were similar across the hospital sample, but varied according to drug/drug class, route of administration, indication and renal function. RDD underestimated actual consumption by 14% overall, while WHO-DDD overestimated total antibacterial consumption by 28% (pooled data; median values RDD −10% versus WHO-DDD +32%). The deviations of estimated from actual drug use volumes were largest for β-lactams (RDD −11% versus WHO-DDD +49%), in particular for penicillins (−11% versus +64%), if WHO-DDD were used. Conclusions Hospital antibiotic consumption surveillance systems using current WHO-DDD should address the uneven discrepancies between actual prescribing and consumption estimates according to drug class that may lead to misclassification in benchmark analyses. We recommend using validated RDD as a supplementary measure to the WHO-DDD for detailed analyses.

Bacterial aminoacyl-tRNA synthetases (aaRSs) represent promising antibacterial drug targets. Unfortunately, the aaRS inhibitors that have to date reached clinical trials are subject to rapid resistance development through mutation, a phenomenon that limits their potential clinical utility. Here, we confirm the intuitively correct idea that simultaneous targeting of two different aaRS enzymes prevents the emergence of spontaneous bacterial resistance at high frequency, a finding that supports the development of multitargeted anti-aaRS therapies.

The objective of this study was to assess the occurrence of drug residues in the raw milk collected from individual farms and milk collection points during 2009–2010 in six different major regions of Kosovo (Prishtine, Gjilan, Mitrovice, Peje, Gjakove, Prizren). In the present study, a total of 1734 raw milk samples were collected, and qualitatively screened with two different tests, the Delvotest SP assay and an enzyme-linked receptor-binding assay (SNAP). Overall, 106 (6.11%) out of 1734 samples examined with Delvotest SP contained possible drug residues (5.12% and 7.51% of samples from 2009 and 2010, respectively). All suspect samples were further analyzed by three distinct enzyme-linked receptor-binding assays specific for β-lactams (new β-lactam test), tetracyclines (SNAP tetracycline test), and sulfonamides (SNAP sulfamethazine test). Only the new SNAP β-lactam test detected residues in 40 out of 52 samples in 2009 and 54 out of 54 suspect samples in 2010. A confirmatory method based on liquid chromatography-tandem mass spectrometry was used to confirm the presence of β-lactam drug residues in samples detected by the enzyme-linked receptor-binding assay. Amoxicillin, penicillin G, and cloxacillin were the most frequently detected residues and were in a concentration range between 2.1 μg/kg and 1973 μg/kg. Seventeen of the positive samples exceeded the maximum residue levels for one or more β-lactam drug. The highest number of positive milk samples came from the Peje Region (58.8%) and Gjakove Region (23.5%), and the lowest number of positive samples originated from Gjilan (5.88%), with no positive samples detected in two regions, Mitrovice and Prizren.

Efforts to reduce the global burden of bacterial disease and contend with escalating bacterial resistance are spurring innovation in antibacterial drug and biocide development and related technologies such as photodynamic therapy and photochemical disinfection. Elucidation of the mechanism of action of these new agents and processes can greatly facilitate their development, but it is a complex endeavour. One strategy that has been popular for many years, and which is garnering increasing interest due to recent technological advances in microscopy and a deeper understanding of the molecular events involved, is the examination of treated bacteria for changes to their morphology and ultrastructure. In this review, we take a critical look at this approach. Variables affecting antibacterial-induced alterations are discussed first. These include characteristics of the test organism (eg. cell wall structure) and incubation conditions (eg. growth medium osmolarity). The main body of the review then describes the different alterations that can occur. Micrographs depicting these alterations are presented, together with information on agents that induce the change, and the sequence of molecular events that lead to the change. We close by highlighting those morphological and ultrastructural changes which are consistently induced by agents sharing the same mechanism (eg. spheroplast formation by peptidoglycan synthesis inhibitors), and explaining how changes that are induced by multiple antibacterial classes (eg. filamentation by DNA synthesis inhibitors, FtsZ disruptors, and other types of agent) can still yield useful mechanistic information. Lastly, recommendations are made regarding future study design and execution.

The discovery and development of antibacterial drugs in the twentieth century were major scientific and medical achievements that have had profound benefits for human society. However, in the twenty-first century the widespread global occurrence of bacteria resistant to the antibiotics and synthetic drugs discovered in the previous century threatens to reverse our ability to treat infectious diseases. Although some new drugs are in development they do not adequately cover growing medical needs. Furthermore, these drugs are mostly derivatives of older classes already in use and therefore prone to existing bacterial resistance mechanisms. Thus, new drug classes are urgently needed. Despite investment in antibacterial drug discovery, no new drug class has been discovered in the past 20 years. In this review, based upon my career as a research scientist in the field of antibacterial drug discovery, I consider some of the technical reasons for the recent failure and look to the future developments that may help to reverse the poor current success rate. Diversification of screening libraries to include new natural products will be important as well as ensuring that the promising drug hits arising from structure-based drug design can achieve effective concentrations at their target sites within the bacterial cell.

New antibacterial drugs are urgently needed to combat the growing problem of multidrug resistant bacterial infections. Major advances in bacterial genomics have uncovered many unexploited targets, leading to the possibility of discovering new antibacterials with novel mechanisms that would circumvent resistance. Many of these targets are soluble enzymes that vary in their degrees of mechanistic complexity. Protein crystallography as well as solution based biophysical methods are playing an increasingly important role in selecting, characterizing and validating promising targets as well as identifying and optimizing lead compounds that inhibit their functions. Advances made in recent years in sensitivity, resolution and throughput of biophysical tools are allowing multiple approaches to screening for hits and rational design of leads based on a deeper understanding of structure-activity relationships. However, the path from a lead compound to a safe and efficacious antibacterial drug still remains challenging. Structural and biophysical approaches have had less of an impact on this later phase of discovery than on the lead generation phase.

New resistance challenges continue to evolve and spread worldwide. In an otherwise mature field, antibacterial drug development is primarily driven by resistance trends with a focus on development of new analogs of known scaffolds to strengthen them against class-specific resistance mechanisms. Currently new analogs of cephalosporins (with or without beta-lactamase inhibitors), oxazolidinones, glycopeptides, quinolones, aminoglycosides, tetracyclines, and ketolides are in clinical studies. While showing some benefit, these new analogs only partially address the clinical crisis of multidrug-resistant pathogens; this is especially the case for Gram-negative bacteria. The medical community faces grim reality — general solutions to the treatment of rapidly spreading multidrug-resistant bacteria are neither on the horizon nor anticipated.

The purpose of the investigation was to determine the effect of the combined antibacterial drug Fenitil on the integral indices of vital functions of animals. It was established on white mice and rats that the drug in various doses doesn’t have a negative effect on integral indices (behavior, compensatory adaptive capabilities, gastrointestinal motor-evacuatory function)during long-term administration.

A decline in antibacterial drug development coupled with emerging bacterial resistance has resulted in limited treatment options. One of the challenges facing antibacterial drug development is appropriate clinical trial designs. Noninferiority trials are appropriate to study new antibacterial drugs for the treatment of serious diseases; superiority trials can be challenging and cannot be the only acceptable trial design to study antibacterial drugs. Our efforts must continue to make new therapies available to meet patient needs.

Mur ligases participate in the intracellular path of bacterial peptidoglycan biosynthesis and constitute attractive, although so far underexploited, targets for antibacterial drug discovery. A series of hydroxy-substituted 5-benzylidenethiazolidin-4-ones were synthesized and tested as inhibitors of Mur ligases. The most potent compound 5 a was active against MurD-F with IC(50) values between 2 and 6 microm, making it a promising multitarget inhibitor of Mur ligases. Antibacterial activity against different strains, inhibitory activity against protein kinases, mutagenicity and genotoxicity of 5 a were also investigated, and kinetic and NMR studies were conducted.