Culture Device Research Articles

Evaluation of distribution and susceptibility of microorganisms isolated from joint fluid cultures: five-year data

Aims: Septic arthritis is joint inflammation. It is an orthopedic emergency that requires prompt diagnosis and treatment. In this study, it was aimed to examine the distribution and antibiotic resistance profiles of microorganisms isolated from joint fluid samples taken from patients who applied to the orthopedic clinic of our hospital in the last five years. 
 Methods: In our study, 1162 joint fluid samples were sent to the medical microbiology laboratory of our hospital from the orthopedics and traumatology clinic between January 01, 2018 and December 31, 2022. Joint fluid samples taken from clinically appropriate patients under sterile conditions were incubated in a BacT/Alert 3D (Biomerieux, France) culture device. Bacteria isolated from 164 specimens with growth detected, were identified by matrix-mediated laser desorption/ionization-time-of-flight mass spectrometry (MALDI-TOF MS) based VITEK MS (Biomerieux, France). Antibiotic susceptibility tests were performed on the VITEK 2 Compact (Biomerieux, France) device.
 Results: Staphylococcus aureus (S. aureus) (29.3%) and coagulase negative Staphylococci (CNS) (29.3%) were the most commonly grown microorganisms. Other microorganisms grown were Streptococcus spp. (9.1%), Enterococcus spp. (6.1%), Pseudomonas aeruginosa (P. aeuruginosa) (7.3%), Escherichiae coli (E. coli) (4.3%) and Klebsiella pneumoniae (K. pneumoniae) (4.3%). When antibiotic susceptibility results were evaluated according to EUCAST restricted reporting criteria, linezolid in Gram-positive strains, amikacin in Enterobacterales, colistin and tigecycline in nonfermentative Gram-negative bacteria were found to be the most susceptible antibiotics. 
 Conclusion: The continuous change in antibiotic susceptibility profiles in joint infections, the long duration of treatment and follow-up, and the increase in polymicrobial infections require regular monitoring of culture and antibiotic susceptibility tests. In our study, the distribution of microorganisms isolated from joint fluid samples of our hospital and the determination of antibiotic resistance profiles will contribute to the clinician in terms of guiding empirical treatment.

Special Issue on Bio-MEMS

A Micro Electro-Mechanical System (MEMS) is a micro-sized mechatronic device based on semiconductor integrated-circuit manufacturing technology. MEMS technology is inherently a very powerful tool for researchers to manipulate and measure the microscopic biological components of biological tissues since their basic constituent units, cells and intracellular microstructures, are also micron or even submicron in size. MEMS technology applied to medicine and life sciences is called Bio-MEMS. Many Bio-MEMS devices and technologies have been developed in recent years, including microfluidic devices for cell culture, manipulation, and measurement, as well as lab-on-a-chip devices for chemical reactions and analyses on MEMS devices. This special issue consists of 13 papers: 1 review article, 1 letter, and 11 research papers. These papers include studies on mechanical stress on cells using MEMS devices, the control of cell functions through microfabrication techniques, cell measurement and in vivo microenvironment simulation using microfluidic devices, and basic research on wearable devices and self-assembling microstructures using MEMS technologies. The editorial committee members are confident that this special issue will make a significant contribution to the further development of Bio-MEMS. We sincerely appreciate the excellent contributions of the authors and the time and effort of the reviewers. We would also like to thank the editorial board of the Journal of Robotics and Mechatronics for their support of this special issue.

Perezhivanie: An investigation into drama and emotions as children enter a conceptual Playworld

A growing number of studies have investigated play in early childhood education, with some bringing forward the development of emotions in imaginary play situations. Of significance, is the creative pedagogy of play developed by Lindqvist (1995) who drew on a cultural-historical concept of play to bring forward emotions in Playworld. This paper investigates how children experience different perezhivanie within the Playworld settings in Indonesia. The cultural-historical concept of play, perezhivanie, and the social situation of development are used to understand how a 4-year-old boy experienced contradictions during collective imaginary play. Eight hours of digital-visual observation data selected from 98 h of group-play activities were used to show how nine teachers interacted with 38 children during the play (3.5 to 5 years old, mean age 4.4 years). The findings show how the cultural device used in the Playworld provides rich opportunities and conditions for children to experience different emotions in play, and where a dynamic perezhivanie emerges through the contributions of the play partners to the play that results in development of emotional regulation. By drawing attention to children's perezhivanie, Playworld can be seen as a promising play pedagogy that offers rich social interactions in play that support children's development.

Hybrid photobioreactor operation for the intensified production of Haslea ostrearia and marennine in function of strain variability

Marennine is a high-value compound produced by the benthic diatom Haslea ostrearia, which could be used as an alternative to synthetic antibiotics in aquaculture. Over the last few years, however, low production rates have been impeding its exploitation. Recent progress on H. ostrearia culture devices led to the design of a particular photobioreactor (PBR) for high yield marennine production, which remained to be further studied: the objective of this study is thus to evaluate the advantages of using a submerged membrane photobioreactor (MPBR) for the culture of H. ostrearia by testing the reliability of its performances when changing strains. In addition, the impact of the decrease in cell size through time, as experienced by H. ostrearia along its life cycle, was studied in regard to marennine productivity, thus considering inter- and intra-strain variability. Using the 1 L MPBR proposed by Gargouch et al. (2022) three different strains of H. ostrearia were cultivated in a fed-batch mode and marennine was collected in a semicontinuous way (D = 0,1 d−1) with an ultrafiltration membrane immersed in the culture. Biometrics of the inocula were measured, and biomass development and marennine production were followed over 20 days of culture. Results confirmed the advantage brought by the addition of a membrane inside the culture chamber enabling to maintain a minimal productivity of 2 mg d−1, using only 3 L of fresh culture medium over a 20-day culture. Results also showed that cell downsizing along H. ostrearia life cycle did impact marennine productivity per cell, with smaller cells (i.e. older strains), displaying a 4 to 15 times increase in biovolumetric marennine productivity depending on the strain. Hypotheses explaining this increase in marennine production along the life cycle of H. ostrearia are discussed, considering also changes in the microbiome or epigenetic variations along strain life cycle.

Parylene-C Coating Protects Resin-3D-Printed Devices from Material Erosion and Prevents Cytotoxicity toward Primary Cells.

Resin 3D printing is attractive for the rapid fabrication of microscale cell culture devices, but common resin materials are unstable and cytotoxic under culture conditions. Strategies such as leaching or overcuring are insufficient to protect sensitive primary cells such as white blood cells. Here, we evaluated the effectiveness of using a parylene C coating of commercially available clear resins to prevent cytotoxic leaching, degradation of microfluidic devices, and absorption of small molecules. We found that parylene C significantly improved both the cytocompatibility with primary murine white blood cells and the material integrity of prints while maintaining the favorable optical qualities held by clear resins.

Studying sprouting angiogenesis under combination of oxygen gradients and co-culture of fibroblasts using microfluidic cell culture model.

Sprouting angiogenesis is an essential process for expanding vascular systems under various physiological and pathological conditions. In this paper, a microfluidic device capable of integrating a hydrogel matrix for cell culture and generating stable oxygen gradients is developed to study the sprouting angiogenesis of endothelial cells under combinations of oxygen gradients and co-culture of fibroblast cells. The endothelial cells can be cultured as a monolayer endothelium inside the device to mimic an existing blood vessel, and the hydrogel without or with fibroblast cells cultured in it provides a matrix next to the formed endothelium for three-dimensional sprouting of the endothelial cells. Oxygen gradients can be stably established inside the device for cell culture using the spatially-confined chemical reaction method. Using the device, the sprouting angiogenesis under combinations of oxygen gradients and co-culture of fibroblast cells is systematically studied. The results show that the oxygen gradient and the co-culture of fibroblast cells in the hydrogel can promote sprouting of the endothelial cells into the hydrogel matrix by altering cytokines in the culture medium and the physical properties of the hydrogel. The developed device provides a powerful in vitro model to investigate sprouting angiogenesis under various in vivo-like microenvironments.

Cultural relic reconstruction device based on ORB-SLAM

ORB-SLAM, an advanced visual SLAM technology, has excellent positioning and mapping capabilities [1]. In the reconstruction of cultural relics, ORB-SLAM technology can achieve autonomous perception and modeling of the surrounding environment of cultural relics by fusing and analyzing the images of monocular depth cameras, thereby reconstructing the 3D model of cultural relics, providing new possibilities for the protection and inheritance of cultural relics. Point cloud images are a digital technology used for 3D modeling, which can save point data on object surfaces and their relationships as 3D point clouds [2]. In terms of cultural relic reconstruction, point cloud images can restore and reconstruct the shape, size, texture, and other features of cultural relics by processing the collected point data on the surface of cultural relics into a 3D model. The purpose of this device is to reconstruct cultural relics by generating point cloud images based on ORB-SLAM technology. Combined with the designed handheld pan tilt device, it can achieve multi-angle point cloud mapping of cultural relics scenes in complex terrain. This paper will introduce the handheld gimbal design of the device, the realization of point cloud mapping based on the ORB-SLAM3 algorithm [3], and the application of point cloud scenes. Through the research in this article, it is expected to provide a new and efficient method for cultural relic reconstruction in the field of cultural relic protection and make contributions to the protection and inheritance of cultural heritage.

Biotechnological advances and applications of human pluripotent stem cell-derived heart models.

In recent years, significant biotechnological advancements have been made in engineering human cardiac tissues and organ-like models. This field of research is crucial for both basic and translational research due to cardiovascular disease being the leading cause of death in the developed world. Additionally, drug-associated cardiotoxicity poses a major challenge for drug development in the pharmaceutical and biotechnological industries. Progress in three-dimensional cell culture and microfluidic devices has enabled the generation of human cardiac models that faithfully recapitulate key aspects of human physiology. In this review, we will discuss 3D pluripotent stem cell (PSC)-models of the human heart, such as engineered heart tissues and organoids, and their applications in disease modeling and drug screening.

A 3D Microfluidic Device with Vertical Channels toward In Vitro Reconstruction of Blood-Brain Barrier.

This paper reports a three-dimensional microfluidic device with an array of vertical channels to enable regulated, continuous, vertical flows to emulate the environment for in vitro culturing of brain and blood vessel organoids. This is expected to ultimately lead to in vitro reconstruction of the blood-brain barrier that is of high interest to studies on mental illness mechanisms and drug delivery to the brain. Twelve vertical microfluidic channels, each with 300 µm diameter and 5 mm height, were formed in the high-permeability agar gel surrounding the organoid to realize the vertical circulation flows and to allow lateral diffusion flows. The combined vertical flow rate of all channels ranges from 2.1 to 6.8 mL/min under different control parameters. A 30-day-old human blood vessel organoid was planted into the device for initial culturing and flow function tests. The result indicates that the organoid was properly activated with effective flow generation in the culturing site of the device.

Pumped and pumpless microphysiological systems to study (nano)therapeutics.

Fluidic microphysiological systems (MPS) are microfluidic cell culture devices that are designed to mimic the biochemical and biophysical in vivo microenvironments of human tissues better than conventional petri dishes or well-plates. MPS-grown tissue cultures can be used for probing new drugs for their potential primary and secondary toxicities as well as their efficacy. The systems can also be used for assessing the effects of environmental nanoparticles and nanotheranostics, including their rate of uptake, biodistribution, elimination, and toxicity. Pumpless MPS are a group of MPS that often utilize gravity to recirculate cell culture medium through their microfluidic networks, providing some advantages, but also presenting some challenges. They can be operated with near-physiological amounts of blood surrogate (i.e., cell culture medium) that can recirculate in bidirectional or unidirectional flow patterns depending on the device configuration. Here we discuss recent advances in the design and use of both pumped and pumpless MPS with a focus on where pumpless devices can contribute to realizing the potential future role of MPS in evaluating nanomaterials. This article is categorized under: Therapeutic Approaches and Drug Discovery > Emerging Technologies Toxicology and Regulatory Issues in Nanomedicine > Toxicology of Nanomaterials.

Design and evaluation of a 3D-printed, lab-scale perfusion bioreactor for novel biotechnological applications.

3D-printing increased in significance for biotechnological research as new applications like lab-on-a-chip systems, cell culture devices or 3D-printed foods were uncovered. Besides mammalian cell culture, only few of those applications focus on the cultivation of microorganisms and none of these make use of the advantages of perfusion systems. One example for applying 3D-printing for bioreactor development is the microbial utilization of alternative substrates derived from lignocellulose, where dilute carbon concentrations and harmful substances present a major challenge. Furthermore, quickly manufactured and affordable 3D-printed bioreactors can accelerate early development phases through parallelization. In this work, a novel perfusion bioreactor system consisting of parts manufactured by fused filament fabrication (FFF) is presented and evaluated. Hydrophilic membranes are used for cell retention to allow the application of dilute substrates. Oxygen supply is provided by membrane diffusion via hydrophobic polytetrafluoroethylene membranes. An exemplary cultivation of Corynebacterium glutamicum ATCC 13032 supports the theoretical design by achieving competitive biomass concentrations of 18.4gL-1 after 52h. As a proof-of-concept for cultivation of microorganisms in perfusion mode, the described bioreactor system has application potential for bioconversion of multi-component substrate-streams in a lignocellulose-based bioeconomy, for in-situ product removal or design considerations of future applications for tissue cultures. Furthermore, this work provides a template-based toolbox with instructions for creating reference systems in different application scenarios or tailor-made bioreactor systems.

High-Efficiency Single-Cell Containment Microdevices Based on Fluid Control.

In this study, we developed a comb-shaped microfluidic device that can efficiently trap and culture a single cell (bacterium). Conventional culture devices have difficulty in trapping a single bacterium and often use a centrifuge to push the bacterium into the channel. The device developed in this study can store bacteria in almost all growth channels using the flowing fluid. In addition, chemical replacement can be performed in a few seconds, making this device suitable for culture experiments with resistant bacteria. The storage efficiency of microbeads that mimic bacteria was significantly improved from 0.2% to 84%. We used simulations to investigate the pressure loss in the growth channel. The pressure in the growth channel of the conventional device was more than 1400 PaG, whereas that of the new device was less than 400 PaG. Our microfluidic device was easily fabricated by a soft microelectromechanical systems method. The device was highly versatile and can be applied to various bacteria, such as Salmonella enterica serovar Typhimurium and Staphylococcus aureus.

Carrier bag storytelling with coastal Kenyan families: sharing food, illustrations, and knowledge for tangible environmental justice impacts

The small-scale fisheries food system, in which individuals achieve food security independently or in small groups through fishing livelihoods and/or subsistence activities, provides food sovereignty for millions globally. However, this arrangement has inequitable engagement due to strictly enforced gendered roles in many communities, including coastal Kenya. Recently, critics across environmental research disciplines have called for social justice in science through anticolonial, feminist methodologies and interdisciplinary praxis. This resistance may take form through the “carrier bag” ability of fiction: an allusion to Le Guin's visionary analysis of containers as the first cultural device and evidence of the power of a story or personal sovereignty to tell one's story. Drawing from creative, service-driven methodologies emerging from collaboration among international research team members and Indigenous research participants, this project uses the “carrier bag” framework to support local environmental justice and food sovereignty goals through a science storybook resource created and shared with fishing families in Kilifi County, Kenya. We investigate how stories shape interpersonal relations in the context of this collaboration and how health knowledge, environmental science, and representational imagery can be tools for justice by examining the connections between social identity, family values, and social-ecological change in this food system. Having a deeper understanding of the experiences, changing ecosystems, and research feedback of these families allows this work to support fisheries management and nutrition interventions in Kenya and communities elsewhere.

On-chip real-time impedance monitoring of hiPSC-derived and artificial basement membrane-supported endothelium

Recent advances have shown the high sensibility of electrochemical impedance spectroscopy in real-time monitoring of cell barriers on a chip. Here, we applied this method to the investigation of human induced pluripotent stem cell (hiPSC) derived and artificial basement membrane (ABM) supported endothelial barrier. The ABM was obtained by self-assembling type IV collagen and laminin with a monolayer of crosslinked gelatin nanofibers. The hiPSCs were differentiated into brain microvascular endothelial cells (BMECs) and then plated on the ABM. After incubation for two days, the ABM-BMEC assembly was placed as a tissue insert into a microfluidic device for culture and real-time impedance monitoring over days. We found a significantly enhanced stability of the BMEC barrier in a serum-free and bromodeoxyuridine (BrdU) containing culture medium compared to the conventional culture due to the restricted cell proliferation. We also found that the BMEC barrier was sensitive to stimuli such as thrombin and that the change of the barrier impedance was mainly due to the change of the cell layer resistance. We can thus advocate this method to investigate the integrity of the cell barrier and the barrier-based assays.

Nature and Culture: A Comparative Reading of Selected Caribbean Novels

This article titled ‘Nature and Culture: A Comparative Reading of Selected Caribbean Novels’ examines the depiction of nature in relation to human culture in Michael Anthony’s The Year in San Fernando (1965), Herbert De Lisser’s Jane’s Career (1972), Earl Lovelace’ The Dragon Can’t Dance (1979) and Rene Maran’s Batouala (1922) to reveal areas where they show sameness in their attempts to evoke human culture with the undercurrent connectedness to nature. The research deploys the insights and poetics of Ecocriticism to the evaluation of the selected texts to demonstrate their signification of the interactivity of nature and culture in their interdependence and mutual constitutiveness in the Caribbean ecosystem. The involvement of man in the exploitation of nature and the effect that it has on the social texture of society is also part of the focus of this paper. The study is situated in the second wave of the literary development of the field, where the purview of Ecocriticism locates vestiges of nature in urban areas. It thus makes for the possibility of analysing works that are not necessarily interested in nature, since the selected texts had been written before the evolvement of Ecocriticism to examine nature-oriented works. In a careful survey of the Caribbean literary works that have been subjected to a comparative lens, the selected texts are found not to have been given nature-oriented attention in a combined form as done in this research. The texts argue that there is a confluence of environment and miscegenation, slavery, identity formation, etc in the understanding of Caribbean literature. This paper posits that writers should reinvent portraying nature, not as a framing device for human culture. This would serve as a stimulus for reorganising Caribbean political thought.

Easy-to-Build and Reusable Microfluidic Device for the Dynamic Culture of Human Bronchial Cystic Fibrosis Epithelia.

Cystic fibrosis (CF) is one of the most frequent genetic diseases, caused by dysfunction of the CF transmembrane conductance regulator (CFTR) chloride channel. CF particularly affects the epithelium of the respiratory system. Therapies aim at rescuing CFTR defects in the epithelium, but CF genetic heterogeneity hinders the finding of a single and generally effective treatment. Therefore, in vitro models have been developed to study CF and guide patient therapy. Here, we show a CF model on-chip by coupling the feasibility of the human bronchial epithelium differentiated in vitro at the air-liquid interface and the innovation of microfluidics. We demonstrate that the dynamic flow enhanced cilia distribution and increased mucus quantity, thus promoting tissue differentiation in a short time. The microfluidic devices highlighted differences between CF and non-CF epithelia, as shown by electrophysiological measures, mucus quantity, viscosity, and the analysis of ciliary beat frequency. The described model on-chip may be a handy instrument for studying CF and setting up therapies. As a proof of principle, we administrated the corrector VX-809 on-chip and observed a decrease in mucus thickness and viscosity.

Application of a sepsis flow chip (SFC) assay for the molecular diagnosis of paediatric sepsis.

A delay in detecting sepsis pathogens is a problematic issue for determining definitive antibiotic therapy for the causative pathogens. The gold standard method for sepsis is blood culture but this requires 3 days to detect the definitive pathogen. Molecular methods offer rapid identification of pathogens. We evaluated the use of sepsis flow chip (SFC) assay for identifying pathogens from children with sepsis. Blood samples from children with sepsis were collected and incubated in a culture device. Positive samples were subjected to amplification-hybridization using SFC assay and culture. A total of 94 samples from 47 patients were recovered, from which 25 isolates were recovered, including Klebsiella pneumoniae (11) and Staphylococcus epidermidis (6). From 25 positive blood culture bottles subjected to SFC assay, 24 genus/species and 18 resistance genes were detected. The sensitivity, specificity and conformity was 80, 94.2 and 94.68 % respectively. SFC assay offers promise to identify pathogens from positive blood culture in paediatric patients with sepsis and may support the antimicrobial stewardship programme in hospitals.

Hypoxia Promotes Cartilage Regeneration in Cell-Seeded 3D-Printed Bioscaffolds Cultured with a Bespoke 3D Culture Device

In this study, we investigated the effect of oxygen tension on the expansion of ADMSCs and on their differentiation toward their chondrocytic phenotype, regenerating a lab-based cartilaginous tissue with superior characteristics. Controversial results with reference to MSCs that were cultured under different hypoxic levels, mainly in 2D culturing settings combined with or without other biochemical stimulus factors, prompted our team to study the role of hypoxia on MSCs chondrogenic differentiation within an absolute 3D environment. Specifically, we used 3D-printed honeycomb-like PCL matrices seeded with ADMSCs in the presence or absence of TGF and cultured with a prototype 3D cell culture device, which was previously shown to favor nutrient/oxygen supply, cell adhesion, and infiltration within scaffolds. These conditions resulted in high-quality hyaline cartilage that was distributed uniformly within scaffolds. The presence of the TGF medium was necessary to successfully produce cartilaginous tissues with superior molecular and increased biomechanical properties. Despite hypoxia's beneficial effect, it was overall not enough to fully differentiate ADMSCs or even promote cell expansion within 3D scaffolds alone.

Gradient to sectioning CUBE workflow for the generation and imaging of organoids with localized differentiation

Advancements in organoid culture have led to various in vitro mini-organs that mimic native tissues in many ways. Yet, the bottleneck remains to generate complex organoids with body axis patterning, as well as keeping the orientation of organoids during post-experiment analysis processes. Here, we present a workflow for culturing organoids with morphogen gradient using a CUBE culture device, followed by sectioning samples with the CUBE to retain information on gradient direction. We show that hiPSC spheroids cultured with two separated differentiation media on opposing ends of the CUBE resulted in localized expressions of the respective differentiation markers, in contrast to homogeneous distribution of markers in controls. We also describe the processes for cryo and paraffin sectioning of spheroids in CUBE to retain gradient orientation information. This workflow from gradient culture to sectioning with CUBE can provide researchers with a convenient tool to generate increasingly complex organoids and study their developmental processes in vitro.

Expansion Culture of Hair Follicle Stem Cells through Uniform Aggregation in Microwell Array Devices.

Hair regeneration using hair follicle stem cells (HFSCs) and dermal papilla cells is a promising approach for the treatment of alopecia. One of the challenges faced in this approach is the quantitative expansion of HFSCs while maintaining their hair induction capacity. In this study, HFSC expansion was achieved through the formation of uniform-diameter cell aggregates that were subsequently encapsulated in Matrigel. We designed a microwell array device, wherein mouse HFSCs were seeded, allowed to form loosely packed aggregates for an hour, and then embedded in Matrigel. Quantitative analysis revealed a 20-fold increase in HFSC number in 2 weeks through this culture device. Gene expression of trichogenic stem cell markers in the device-grown cells showed a significant increase compared with that of typical flat substrate Matrigel suspension culture cells. These microwell array-cultured HFSCs mixed with freshly isolated embryonic mesenchymal cells indicated vigorous hair regeneration on the skin of nude mice. Furthermore, we examined the feasibility of this approach for the expansion of human HFSCs from androgenetic alopecia patients and found that the ratio of CD200+ cells was improved significantly in comparison with that of cells cultured in a typical culture dish or in a Matrigel suspension culture on a flat substrate. Therefore, the novel approach proposed in this study may be useful for HFSC expansion in hair regenerative medicine.