Full Profiling of GE81112A, an Underexplored Tetrapeptide Antibiotic with Activity against Gram-Negative Pathogens.

After the first total synthesis combined with structure revision, we performed thorough in vitro and in vivo profiling of the underexplored tetrapeptide GE81112A. From the determination of the biological activity spectrum and physicochemical and early absorption-distribution-metabolism-excretion-toxicity (eADMET) properties, as well as in vivo data regarding tolerability and pharmacokinetics (PK) in mice and efficacy in an Escherichia coli-induced septicemia model, we were able to identify the critical and limiting parameters of the original hit compound. Thus, the generated data will serve as the basis for further compound optimization programs and developability assessments to identify candidates for preclinical/clinical development derived from GE81112A as the lead structure. IMPORTANCE The spread of antimicrobial resistance (AMR) is becoming a more and more important global threat to human health. With regard to current medical needs, penetration into the site of infection represents the major challenge in the treatment of infections caused by Gram-positive bacteria. Considering infections associated with Gram-negative bacteria, resistance is a major issue. Obviously, novel scaffolds for the design of new antibacterials in this arena are urgently needed to overcome this crisis. Such a novel potential lead structure is represented by the GE81112 compounds, which inhibit protein synthesis by interacting with the small 30S ribosomal subunit using a binding site distinct from that of other known ribosome-targeting antibiotics. Therefore, the tetrapeptide antibiotic GE81112A was chosen for further exploration as a potential lead for the development of antibiotics with a new mode of action against Gram-negative bacteria.

Antimicrobial Peptides from Rat-Tailed Maggots of the Drone Fly Eristalis tenax Show Potent Activity against Multidrug-Resistant Gram-Negative Bacteria.

The spread of multidrug-resistant Gram-negative bacteria is an increasing threat to human health, because novel compound classes for the development of antibiotics have not been discovered for decades. Antimicrobial peptides (AMPs) may provide a much-needed breakthrough because these immunity-related defense molecules protect many eukaryotes against Gram-negative pathogens. Recent concepts in evolutionary immunology predict the presence of potent AMPs in insects that have adapted to survive in habitats with extreme microbial contamination. For example, the saprophagous and coprophagous maggots of the drone fly Eristalis tenax (Diptera) can flourish in polluted aquatic habitats, such as sewage tanks and farmyard liquid manure storage pits. We used next-generation sequencing to screen the E. tenax immunity-related transcriptome for AMPs that are synthesized in response to the injection of bacterial lipopolysaccharide. We identified 22 AMPs and selected nine for larger-scale synthesis to test their activity against a broad spectrum of pathogens, including multidrug-resistant Gram-negative bacteria. Two cecropin-like peptides (EtCec1-a and EtCec2-a) and a diptericin-like peptide (EtDip) displayed strong activity against the pathogens, even under simulated physiological conditions, and also achieved a good therapeutic window. Therefore, these AMPs could be used as leads for the development of novel antibiotics.

Profiling antimicrobial peptides from the medical maggot Lucilia sericata as potential antibiotics for MDR Gram-negative bacteria.

Background: The ability of MDR Gram-negative bacteria to evade even antibiotics of last resort is a severe global challenge. The development pipeline for conventional antibiotics cannot address this issue, but antimicrobial peptides (AMPs) offer an alternative solution. Objectives: Two insect-derived AMPs (LS-sarcotoxin and LS-stomoxyn) were profiled to assess their suitability for systemic application in humans. Methods: The peptides were tested against an extended panel of 114 clinical MDR Gram-negative bacterial isolates followed by time-kill analysis, interaction studies and assays to determine the likelihood of emerging resistance. In further in vitro studies we addressed cytotoxicity, cardiotoxicity and off-target interactions. In addition, an in vivo tolerability and pharmacokinetic study in mice was performed. Results: LS-sarcotoxin and LS-stomoxyn showed potent and selective activity against Gram-negative bacteria and no cross-resistance with carbapenems, fluoroquinolones or aminoglycosides. Peptide concentrations of 4 or 8 mg/L inhibited 90% of the clinical MDR isolates of Escherichia coli, Enterobacter cloacae, Acinetobacter baumannii and Salmonella enterica isolates tested. The 'all-d' homologues of the peptides displayed markedly reduced activity, indicating a chiral target. Pharmacological profiling revealed a good in vitro therapeutic index, no cytotoxicity or cardiotoxicity, an inconspicuous broad-panel off-target profile, and no acute toxicity in mice at 10 mg/kg. In mouse pharmacokinetic experiments LS-sarcotoxin and LS-stomoxyn plasma levels above the lower limit of quantification (1 and 0.25 mg/mL, respectively) were detected after 5 and 15 min, respectively. Conclusions: LS-sarcotoxin and LS-stomoxyn are suitable as lead candidates for the development of novel antibiotics; however, their pharmacokinetic properties need to be improved for systemic administration.

Biological Profiling of Coleoptericins and Coleoptericin-Like Antimicrobial Peptides from the Invasive Harlequin Ladybird Harmonia axyridis.

The spread of antibiotic-resistant human pathogens and the declining number of novel antibiotics in the development pipeline is a global challenge that has fueled the demand for alternative options. The search for novel drug candidates has expanded to include not only antibiotics but also adjuvants capable of restoring antibiotic susceptibility in multidrug-resistant (MDR) pathogens. Insect-derived antimicrobial peptides (AMPs) can potentially fulfil both of these functions. We tested two coleoptericins and one coleoptericin-like peptides from the invasive harlequin ladybird Harmonia axyridis against a panel of human pathogens. The AMPs displayed little or no activity when tested alone but were active even against clinical MDR isolates of the Gram-negative ESKAPE strains when tested in combination with polymyxin derivatives, such as the reserve antibiotic colistin, at levels below the minimal inhibitory concentration. Assuming intracellular targets of the AMPs, our data indicate that colistin potentiates the activity of the AMPs. All three AMPs achieved good in vitro therapeutic indices and high intrahepatic stability but low plasma stability, suggesting they could be developed as adjuvants for topical delivery or administration by inhalation for anti-infective therapy to reduce the necessary dose of colistin (and thus its side effects) or to prevent development of colistin resistance in MDR pathogens.

[Violence against elderly people. Recognize--Sensitize--Act!]. / Gewalt gegen alte Menschen. Erkennen--Sensibilisieren--Handeln!

Elder abuse is--especially in view of the demographic development--a topic that is still neglected socially and in health policy, but also in terms of scientific research. There are different definitions of violence and these can be difficult to formulate, depending on the field. In gerontology, a rather broad frame is usually used to describe the phenomenon of violence. Its shapes are multilayered and diverse (e.g., physical, psychological, restriction of freedom, neglect, financial exploitation, and structural and cultural). In principle, any act of violence is also a breach of the law. Violence can occur in public places and in family and institutional settings (e.g., hospital and outpatient and inpatient care for the elderly). The statistical occurence in family settings is around 25% and in institutional settings between 11 and 24%. Acts of violence are usually an expression of helplessness, shame, overwork, poor support and lack of knowledge of alternatives. Often there is a pathological relationship, in which the roles of "perpetrators" and "victims" can change. Acts of violence have massive consequences for those affected. Preventative measures to reduce violence have various points of departure (e.g., company, region, institution, professional). So far, there are hardly any points of contact and professional assistance for elderly victims.

Evaluation of a standardized humor group in a clinical setting: a feasibility study for older patients with depression.

BACKGROUND: Positive effects of humor on older patients with depressive symptoms have been repeatedly reported. Empirical evidence however is rare. We investigated the efficacy of a standardized humor therapy group in a clinical context especially for older depressed patients. PATIENTS AND METHODS: An experimental group with treatment (49 patients) was compared with a control group with no treatment (50 patients) in a semi-randomized design. Included were patients with major depression according to ICD-10. A set of questionnaires (Geriatric Depression Scale, Short Form Health Survey, State-Trait-Cheerfulness Inventory, and Satisfaction with Life Scale) was administered pretreatment and posttreatment. RESULTS: Both groups showed improvement for depression, suicidal tendency, state cheerfulness, and state bad mood. Only participants of the humor group showed changes of state seriousness and satisfaction with life (p < 0.05). Further trends could be demonstrated for higher changes in state cheerfulness and resilience for the humor group. CONCLUSION: Our results indicate an additional benefit of this specific therapeutic intervention for older depressed patients.

[Persons with dementia caught between medicine, care and politics]. / Im Spannungsfeld zwischen Medizin, Pflege und Politik: Menschen mit Demenz.

When there is a suggestion of dementia, a thorough diagnostic work up including a comprehensive assessment is needed for the benefit of the old person, his family and society. This provides the basis for needed interventions, including prevention and rehabilitation, in addition to treatment and care. A comprehensive approach is in order since dementia is the single most important cause for care-dependency. Dementia cannot be considered an organic mental disorder alone but has to be viewed in the context of the personhood and living environment of the person afflicted. Because of the diversity of professionals and agencies involved in the provision of care for the person with dementia, a clear delineation between overlapping areas of care as well as coordination of services is needed. At present this is often times not accomplished, resulting in a fragmentation of care and competing responsibilities. Despite many attempts to remedy these pitfalls, problems have remained. The reform of the German long-term care insurance provides many new regulations mandating improved care and more social participation for the person with dementia and his family. To implement this mandate, the coordination of services between the professionals involved, especially between physicians and nursing-care professionals, will be crucial. It has become apparent that separate reimbursement systems in health care insurance and long-term care insurance might well be implicated in deficient levels of care. It has been recommended to place more emphasis on integrated care. Improvements have to be judged by their benefit for the target group. Administrative and technocratic burdens may impede intended goals.

[Medicolegal aspects of witnessed suicide due to gunshot to the head. Part 1: Circumstances and psychopathology]. / Rechtsmedizinische Aspekte des Suizides durch Kopfschuss vor Zeugen. Teil I: Umstände und psychopathologische Befunde.

In the USA the frequency of witnessed suicide, i.e. suicide committed in the presence of at least one further individual, is reported to range between 5 and 15%. As up to now no detailed analysis of this special issue has been given in the medicolegal literature, this article presents and discusses a number of cases including 8 males and 1 female (age 19-58 years, mean 41.2 years) who had all committed suicide by inflicting a gunshot to the head. In 3 cases post-mortem blood alcohol concentrations of 1.73, 1.88 and 2.23 g/kg respectively were observed. Toxicological tests produced negative results. 5 cases had a medical history of psychiatric disorder with endogenous depression in 3, chronic alcohol abuse and drug abuse with concomitant psychosis in one case each. As far as the motives were known, domestic arguments were of prevailing importance. With one exception the suicides were committed at home. In 6 cases one witness was present, in 2 cases 2 individuals and in one case 22 persons witnessed the suicide. The reported cases are discussed in comparison with the psychiatric-psychological classification according to McDowell et al. with the aim to provide a solid and comprehensive medicolegal method to distinguish between homicide and suicide. Furthermore aspects of psychiatric sequelae and psychological support of the witnesses, which are also of importance for the forensic pathologist called to the scene, are discussed.

[Medicolegal aspects of witnessed suicide due to gunshot to the head. II. Legal medicine aspects and examination of the firing hand]. / Rechtsmedizinische Aspekte des Suizides durch Kopfschuss vor Zeugen. Teil II: Rechtsmedizinische Befunde und Schusshanduntersuchung.

The second part of the paper on suicides by gunshots to the head in the presence of witnesses focuses on relevant morphological autopsy findings such as entrance site, signs of close range or contact shots, bullet path etc. and also discusses selected aspects of ascertaining gunshot residues. For the identification of the shooter an integral medicolegal assessment of all the facts including the investigation results and the autopsy findings is essential. However, the morphological findings alone do not allow safe diagnosis, as for example in a homicide the temporal region, which was affected in all our cases, may have been deliberately chosen by the perpetrator as a localization typical of suicide. Thus methods to ascertain gunshot residues on the firing hand (by means of adhesive films and the polyvinyl-alcohol collection method--PVAL) are of great practical importance. In seven cases adhesive films and/or the polyvinyl-alcohol collection method were used. In one case the gunshot residues (GSR) were analysed by means of tape lifts and subsequent scanning electron microscopy (SEM). It was found that especially the combined application of topographical (adhesive tape/PVAL) and cumulative (SEM) methods allowed for the doubtless identification of the shooter, thus usually confirming the suicide. By the example of one case it is demonstrated that without the immediate collection of evidence at the scene objective reconstruction of the event becomes impossible. On the basis of the reported cases recommendations are finally given for a differentiated approach in the medicolegal evaluation of alleged witnessed suicide by gunshot (to the head).