This study examines desiccated tissue samples from mummified human remains removed and excavated from Historic Cave in the Makapan Valley, Limpopo Province using scanning electron microscopy (SEM), ...energy-dispersive spectroscopy (EDS) and light microscopy. A range of methods are employed to clean, rehydrate and stain the desiccated tissue, and the outcomes are compared. Through this comparative analysis it is possible to determine the most suitable method for examining desiccated tissue from Historic Cave. In the SEM analysis, epidermal keratinocytes and vellus hairs were observed on the surface of the skin tissue. Histological analyses demonstrated the exclusive preservation of collagen fibres in the muscle tissue, the connective tissue and the skin tissue. This suggests that the collagen fibres play an integral part in preserving the structure of desiccated tissue that is devoid of cellular elements.
•sonication using absolute alcohol is the preferred method for removing dust or soil from the samples.•for histological examination, rehydration with glycerine gave good preservation of the tissue.•Poorly preserved skin and muscle precludes the diagnosis of underlying pathological skin or muscle disorders.•The hairs were well preserved and those examined by SEM were probed for heavy metals.
The performance of the ring-imaging Cherenkov detectors at the LHCb experiment is determined during the LHC Run 2 period between 2015 and 2018. The stability of the Cherenkov angle resolution and ...number of detected photons with time and running conditions is measured. The particle identification performance is evaluated with data and found to satisfy the requirements of the physics programme.
Staphylococcus aureus is a nosocomial bacterium causing different infectious diseases, ranging from skin and soft tissue infections to more serious and life-threatening infections such as ...septicaemia. S. aureus forms a complex structure of extracellular polymeric biofilm that provides a fully secured and functional environment for the formation of microcolonies, their sustenance and recolonization of sessile cells after its dispersal. Staphylococcus aureus biofilm protects the cells against hostile conditions, i.e., changes in temperature, limitations or deprivation of nutrients and dehydration, and, more importantly, protects the cells against antibacterial drugs. Drugs are increasingly becoming partially or fully inactive against S. aureus as they are either less penetrable or totally impenetrable due to the presence of biofilms surrounding the bacterial cells. Other factors, such as evasion of innate host immune system, genome plasticity and adaptability through gene evolution and exchange of genetic material, also contribute to the ineffectiveness of antibacterial drugs. This increasing tolerance to antibiotics has contributed to the emergence and rise of antimicrobial resistance (AMR), a serious problem that has resulted in increased morbidity and mortality of human and animal populations globally, in addition to causing huge financial losses to the global economy. The purpose of this review is to highlight different aspects of S. aureus biofilm formation and its overall architecture, individual biofilm constituents, clinical implications and role in pathogenesis and drug resistance. The review also discusses different techniques used in the qualitative and quantitative investigation of S. aureus biofilm and various strategies that can be employed to inhibit and eradicate S. aureus biofilm.
Nosocomial infections caused by
spp. are common in veterinary facilities. The early identification of high-risk patients and sources of infection is important for mitigating the spread of infections ...to animal patients and humans. This study investigated the occurrence of
spp. among patients at a veterinary academic hospital in South Africa. In addition, this study describes the environmental factors that contribute to the spread of
spp. in the veterinary facility.
This study used a dataset of
positive animals and environmental samples submitted to the bacteriology laboratory between 2012 and 2019. The occurrence of
isolates at the veterinary hospital was described based on source, month, season, year, and location. Proportions and 95% confidence intervals were calculated for each variable.
A total of 715
isolates were recorded, of which 67.6% (483/715) came from animals and the remainder (32.4%, 232/715) came from environmental samples. The highest proportion (29.2%) of
isolates was recorded in 2016 and most isolates were reported in November (17.4%). The winter season had the lowest (14.6%) proportion of isolates reported compared to spring (31.3%), summer (27.8%), and autumn (26.4%).
Typhimurium (20.0%) was the most frequently reported serotype among the samples tested, followed by
Anatum (11.2%). Among the positive animal cases, most (86.3%) came from equine clinics. Most reported isolates differed based on animal species with
. Typhimurium being common in equines and
. Anatum in bovines.
In this study,
. Typhimurium emerged as the predominant strain in animal and environmental samples. Equines were the most affected animals; however,
serotypes were also detected in the production animals. Environmental contamination was also a major source of
species in this study. To reduce the risk of transmission, strict infection prevention and control measures (biosecurity) must be implemented.
Amino acids are ubiquitous vital biomolecules found in all kinds of living organisms including those in the microbial world. They are utilised as nutrients and control many biological functions in ...microorganisms such as cell division, cell wall formation, cell growth and metabolism, intermicrobial communication (quorum sensing), and microbial-host interactions. Amino acids in the form of enzymes also play a key role in enabling microbes to resist antimicrobial drugs. Antimicrobial resistance (AMR) and microbial biofilms are posing a great threat to the world's human and animal population and are of prime concern to scientists and medical professionals. Although amino acids play an important role in the development of microbial resistance, they also offer a solution to the very same problem i.e., amino acids have been used to develop antimicrobial peptides as they are highly effective and less prone to microbial resistance. Other important applications of amino acids include their role as anti-biofilm agents, drug excipients, drug solubility enhancers, and drug adjuvants. This review aims to explore the emerging paradigm of amino acids as potential therapeutic moieties.
A library of 53 benzimidazole derivatives, with substituents at positions 1, 2 and 5, were synthesized and screened against a series of reference strains of bacteria and fungi of medical relevance. ...The SAR analyses of the most promising results showed that the antimicrobial activity of the compounds depended on the substituents attached to the bicyclic heterocycle. In particular, some compounds displayed antibacterial activity against two methicillin-resistant Staphylococcus aureus (MRSA) strains with minimum inhibitory concentrations (MICs) comparable to the widely-used drug ciprofloxacin. The compounds have some common features; three possess 5-halo substituents; two are derivatives of (S)-2-ethanaminebenzimidazole; and the others are derivatives of one 2-(chloromethyl)-1H-benzodimidazole and (1H-benzodimidazol-2-yl)methanethiol. The results from the antifungal screening were also very interesting: 23 compounds exhibited potent fungicidal activity against the selected fungal strains. They displayed equivalent or greater potency in their MIC values than amphotericin B. The 5-halobenzimidazole derivatives could be considered promising broad-spectrum antimicrobial candidates that deserve further study for potential therapeutic applications.
A series of novel nopyl-derived chiral phosphonium ionic liquids have been successfully synthesised and characterised. Analysis of each novel ionic liquid was conducted in order to confirm structure, ...purity and thermal stability.
•16 novel nopyl-phosphonium ionic liquids were synthesised and characterised.•Our data suggests these ionic liquids are stable up to approximately 300 °C.•Each ionic liquid demonstrates desirable physical properties.
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