Comparative study of manual conventional blood cultures versus automated blood culture system in cases of septicemia

: Blood cultures are a proven gold standard method for the identification of causative agents of bloodstream infections. Identification of causative organism along with antibiotic susceptibility plays a pivotal role in proposing suitable antibiotic therapy. Automated blood culture systems show improved monitoring of blood cultures by reducing the time and by ensuring more accurate results when compared to the conventional blood culture system. To isolate the organism from given blood samples of a suspected case of septicemia and to compare the results of conventional and automated blood culture systems and to study the antimicrobial susceptibility pattern of the pathogens isolated. A prospective study of 6 months period was conducted among 100 subjects attending the Department of Microbiology in a tertiary care hospital. Subjects with symptoms and signs of septicemia were included. 25ml of venous blood was drawn aseptically from the venipuncture site, of which 5ml of blood was inoculated into 50ml of Brain Heart Infusion bottle in conventional blood culture system and 10ml each into aerobic and anaerobic BACTEC PLUS bottle in Automated blood culture system BACTEC FX40. Overall, 48% and 60% of the samples revealed positive growth by the conventional and automated blood culture system BACTEC FX40, respectively. Gram Positive Cocci were 52.08% and Gram Negative Bacilli were 47.91% isolated by conventional blood culture system, whereas automated blood culture system BACTEC FX40 isolated 45% and 55%, respectively. Isolates were detected within 24-48hrs and 12-24 hrs by conventional and automated blood culture systems, respectively. The anti-microbial susceptibility pattern of the pathogens isolated was also recorded by Kirby Bauer disc diffusion method of antimicrobial susceptiblity testing. Automated blood culture systems are a trustworthy substitute to conventional blood culture systems. The automated blood culture systems being more sensitive and rapid in detecting septicemia in subjects acts as an appropriate means for the initial identification and detection of blood pathogens and improved provision of antimicrobial therapeutic options for septic Patients especially in Critical Care and Intensive Care Units where positive culture reporting is crucial.

Alzheimer’s Disease: Current Perspectives and Advances in Physiological Modeling

Though Alzheimer’s disease (AD) is the most common cause of dementia, complete disease-modifying treatments are yet to be fully attained. Until recently, transgenic mice constituted most in vitro model systems of AD used for preclinical drug screening; however, these models have so far failed to adequately replicate the disease’s pathophysiology. However, the generation of humanized APOE4 mouse models has led to key discoveries. Recent advances in stem cell differentiation techniques and the development of induced pluripotent stem cells (iPSCs) have facilitated the development of novel in vitro devices. These “microphysiological” systems—in vitro human cell culture systems designed to replicate in vivo physiology—employ varying levels of biomimicry and engineering control. Spheroid-based organoids, 3D cell culture systems, and microfluidic devices or a combination of these have the potential to replicate AD pathophysiology and pathogenesis in vitro and thus serve as both tools for testing therapeutics and models for experimental manipulation.

Dactylogyrus Infestation in Farmed Common Carp Cyprinus carpio from Aquaculture Facilities in Macedonia

A total of 958 specimens of farmed common carp Cyprinus carpio from eight of the most significant and largest cyprinid aquaculture facilities in Macedonia (pond and cage culture systems) were examined for parasitological investigation for three years. The following parasite species of the genus Dactylogyrus were identified: Dactylogyrus extensus, Dactylogyrus minutus and Dactylogyrus anchoratus. The highest prevalence was determined for D. extensus (38.8%), followed by D. minutus (7.9%) and D. anchoratus (2.8%). The highest mean intensity was determined for D. extensus (6.2), followed by D. minutus (4.7) and D. anchoratus (3.8). By seasons, the highest prevalence (16.5%) was recorded for D. extensus in winter, while the lowest (0.6%) for D. minutus in autumn. The highest mean intensity (8.0) was also determined for D. extensus in winter, and the lowest (1.9) for D. minutus in spring.

Three-Dimensional Culture Systems for Dissecting Notch Signalling in Health and Disease

Three-dimensional (3D) culture systems opened up new horizons in studying the biology of tissues and organs, modelling various diseases, and screening drugs. Producing accurate in vitro models increases the possibilities for studying molecular control of cell–cell and cell–microenvironment interactions in detail. The Notch signalling is linked to cell fate determination, tissue definition, and maintenance in both physiological and pathological conditions. Hence, 3D cultures provide new accessible platforms for studying activation and modulation of the Notch pathway. In this review, we provide an overview of the recent advances in different 3D culture systems, including spheroids, organoids, and “organ-on-a-chip” models, and their use in analysing the crucial role of Notch signalling in the maintenance of tissue homeostasis, pathology, and regeneration.

3D Cell Culture Systems: Tumor Application, Advantages, and Disadvantages

The traditional two-dimensional (2D) in vitro cell culture system (on a flat support) has long been used in cancer research. However, this system cannot be fully translated into clinical trials to ideally represent physiological conditions. This culture cannot mimic the natural tumor microenvironment due to the lack of cellular communication (cell-cell) and interaction (cell-cell and cell-matrix). To overcome these limitations, three-dimensional (3D) culture systems are increasingly developed in research and have become essential for tumor research, tissue engineering, and basic biology research. 3D culture has received much attention in the field of biomedicine due to its ability to mimic tissue structure and function. The 3D matrix presents a highly dynamic framework where its components are deposited, degraded, or modified to delineate functions and provide a platform where cells attach to perform their specific functions, including adhesion, proliferation, communication, and apoptosis. So far, various types of models belong to this culture: either the culture based on natural or synthetic adherent matrices used to design 3D scaffolds as biomaterials to form a 3D matrix or based on non-adherent and/or matrix-free matrices to form the spheroids. In this review, we first summarize a comparison between 2D and 3D cultures. Then, we focus on the different components of the natural extracellular matrix that can be used as supports in 3D culture. Then we detail different types of natural supports such as matrigel, hydrogels, hard supports, and different synthetic strategies of 3D matrices such as lyophilization, electrospiding, stereolithography, microfluid by citing the advantages and disadvantages of each of them. Finally, we summarize the different methods of generating normal and tumor spheroids, citing their respective advantages and disadvantages in order to obtain an ideal 3D model (matrix) that retains the following characteristics: better biocompatibility, good mechanical properties corresponding to the tumor tissue, degradability, controllable microstructure and chemical components like the tumor tissue, favorable nutrient exchange and easy separation of the cells from the matrix.