The COVID-19 pandemic hit Ecuador severely. The country caught the attention of international media due to its high death toll and overwhelmed healthcare system. The clinical diagnostics system was rapidly overloaded, and the import of PCR tests was delayed. The case of Ecuador illustrates how middle-income countries rely heavily on the importation of biotechnological products for their healthcare systems. The Ecuadorian experience during the COVID-19 pandemic serves as a call for the formation of policies for the development of the biotechnological industry. Ecuador has been one of the hardest-hit Latin American countries during the COVID-19 pandemic . NationwIn March 2020, during the first week of the epidemic in Ecuador, the National Institute for Public Health Research (INSPI) received 6826 samples for COVID-19 diagnosis using RT-PCR in its main lab in the city of Guayaquil. However, the maximum testing capacity of the INSPI laboratory in Guayaquil—the only one in the country authorized to process those samples at the time—was 350 tests per day. By March 18th, the INSPI laboratories in Quito and Cuenca had also begun to process samples to assist with the high testing demand. However, at this point, the entire diagnostics system was quickly overwhelmed, so much so that the delayed sample processing would not have been brought up to date until the end of April 2020 [The diagnostic gold standard for COVID-19 is the polymerase chain reaction (PCR), which is a fundamental technique in diagnosing ongoing SARS-CoV-2 infection. The availability of equipment and reagents needed for real-time PCR diagnostics in many low- and middle-income countries depends entirely on importations, which can be lengthy, bureaucratic, and costly. Importation issues ultimately delay the implementation of widespread testing, increasing the turnover times of test results. In Ecuador, private businesses can require up to 7 weeks for their imports to arrive. This may take several months in the public sector due to the mandatory public procurement procedures and complex processes for selecting qualified local suppliers. The financial burden of this reliance on importations is considerable, with final supply costs reaching as high as 45% above the original retail price. The Ecuadorian government has granted tariff relief to institutions of higher education, yet universities can still only reduce their importation costs to 25% above the actual retail price. Moreover, the successful application of this tariff reduction scheme is slow—it can take at least 12 weeks for supplies to arrive.The application processes that public institutions need to go through to acquire and import tax-free goods are complex and time-consuming under normal conditions, let alone under the high global demand for COVID-19 testing reagents when expediency is essential in securing key assets to maintain a national surveillance program. These challenges call for local and regional capacity building to counteract the negative effect of productive and technological dependency for key reagents and supplies. Despite these challenges, tariff benefits have allowed several universities to provide critical support to testing programs in the country.During the pandemic, academia has become a significant ally to the health sector by providing expertise and data analysis , buildinUnfortunately, the limitations mentioned above are not new for Ecuadorian scientists. Before the beginning of the COVID-19 pandemic, the elevated costs of laboratory supplies and the delays during importation processes were already a burden for academic research . The curEcuador, over the course of the last decade, has made progress amassing highly skilled and specialized human resources, increasing its ability to develop innovative biotechnological solutions which would benefit from competitive incentive programs. The COVID-19 pandemic has shown how nations can generate inventive designs for facing mass diagnostic challenges ; howeverThe Ecuadorian experience during the COVID-19 pandemic illustrates critical shortcomings that other middle-income countries may be experiencing and serves as a call for the establishment of strategies for biotechnological development. An area to be prioritized is the development of products for genomic surveillance and clinical diagnostics, including but not limited to the synthesis of oligonucleotides and the production of antibodies. Such strategies will require participation and contributions from multiple fronts including the public and private sectors, industry, and academia and the establishment of favorable social and commercial conditions for research and innovation.


Background: Left bundle branch pacing (LBBP) is a novel physiological pacing and previous studies have confirmed the feasibility and safety of it. The incidence of complications in LBBP is relatively low as reported. Here we present a case of interventricular septal hematoma complicating LBBP lead implantation.Case summary: LBBP was achieved for treatment of high-grade atrioventricular block in a 67-year-old female. Chest pain began 1 h after implantation when the electrocardiogram showed ST-T changes. Then bedside echocardiography confirmed the formation of interventricular septal hematoma. Urgent coronary angiography showed the contrast agent retention and overflow in the interventricular septum. The symptom was relieved half an hour later. Echocardiogram performed 2 h later revealed the size of the hematoma was the same as before. The electrocardiography, coronary angiography and CTA confirmed the resolution of the hematoma at 1-month follow-up. Pacing parameters and cardiac function remained stable during 6-month follow-up.Conclusion: This is the first reported case describing the clinic features and management of interventricular septum hematoma complicating LBBP. The importance of routine echocardiograms after implantation for identifying the hematoma should be highlighted. His-Purkinje conduction system pacing allows the most physiological left ventricular activation by capturing the conduction bundle and improve clinical outcomes , 2. But Figure 2A) and referred for pacemaker implantation in August 2020. Her medical history showed hypertension and previous stent implantation for the treatment of left anterior descending artery stenosis with long-term clopidogrel medication. The intracardiac electrogram showed infra-Hisian block, and the His bundle capture threshold was 5 V/0.5 ms. Then, we performed left bundle branch pacing. The lead was advanced into the LBB area located below the septal tricuspid valve. The procedural steps for delivering LBBP and detailed criteria to confirm LBB capture have been described previously, the key point of which is to screw deep enough into the septum  relief of symptoms, stable vital signs and normalized ECG; (2) only small amount of contrast agent overflow and retention; (3) no rupture into the pericardium; (4) good response to conservative treatment in previous reports, we chose conservative treatment and close surveillance. In the next few days, considering that dynamic echocardiogram monitoring demonstrated that the hematoma did not progress, contrast wash-out occurred smoothly and the patient's vital signs remained stable, we thought there was no need for intervention and interruption of mono antiplatelet medication . In our To prevent hematoma formation, a series of evaluations are required. Firstly, anticoagulant use should be carefully assessed. Secondly, always bring awareness to anatomical variants of vessels to avoid injury of potentially important arteries, for example, the sinus of Valsalva aneurysm may compress the septum. In patients with vascular malformation, angiography may be needed to help guide the implantation of pacing lead, but it is not routinely used in clinical practice. Thirdly, the number of the sites for lead implantation should be minimized. To avoid damaging the coronary arteries, especially anterior descending artery and large septal perforator branches, the lead should not be placed too anteriorly at the right anterior oblique fluoroscopic view . FourthlLBBP is generally feasible and safe, but the incidence of the hematoma may be underestimated. Whether the clinical course of the hematoma would be uneventful or not, which requires further personalized management.The raw data supporting the conclusions of this article will be made available by the authors, without undue reservation.Written informed consent was obtained from the individual(s) for the publication of any potentially identifiable images or data included in this article.All authors listed have made a substantial, direct and intellectual contribution to the work, and approved it for publication.This work was supported by the Natural Science for Youth Foundation, grant/award no. 81900345; Key Research and Development Program of Zhejiang (grant no. 2019C03012); Major Project of the Science and Technology of Wenzhou (grant no. ZS2017010).The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.


Cell-cell adhesion and the adhesion of cells to extracellular matrix are mediated by the specific binding of receptors on the cell membrane to their cognate ligands on the opposing surface. The adhesion receptors can exhibit affinity for nanoscale lipid clusters that form in the cell membrane. Experimental studies of such adhesion systems often involve a cell adhering either to a solid surface with immobile ligands or a supported lipid bilayer with mobile ligands. A central question in these cell-substrate adhesions is how the mobility of the ligands physically affects their binding to the adhesion receptors and thereby the behavior of the nanoscale lipid clusters associated with the receptors. Using a statistical mechanical model and Monte Carlo simulations for the adhesion of cells to substrates with ligands, we find that, for mobile ligands, binding to adhesion receptors can promote the formation of mesoscale lipid domains, which in turn enhances the receptor-ligand binding. However, in the case of immobile ligands, the receptor-ligand binding and the tendency for the nanoscale lipid clusters to further coalesce depend on the distribution of the ligands on the substrate. Our findings help to explain why different adhesion experiments for identifying the interplay between receptor-ligand binding and heterogeneities in cell membranes led to contradictory results. K of intercellular adhesion molecules not only depends on the specific interaction of receptors and ligands, but also on the membrane physical properties (Cell-cell adhesion and the adhesion of cells to the extracellular matrix (ECM), mediated by the specific binding of receptors and ligands anchored to the apposing surfaces, governs numerous biological processes such as signal transduction, immune responses, cell locomotion, tissue formation, as well as cancer invasion and metastasis . In cell]/[R][L]  that invpiration , flow chpiration , atomic piration , as wellpiration , have beoperties .via cholesterol depletion directly reduces the binding constant K of the T cell receptor (TCR) and peptide-major histocompatibility complexes (pMHC)  . Experims (pMHC) . For thes (pMHC) . For exas (pMHC)  found ths (pMHC)  observedIn this paper, we use methods of classical statistical mechanics and Monte Carlo (MC) simulations to study the interplay between receptor-ligand binding and raft domain formation for two typical experimental systems of cell adhesion, where multicomponent membranes adhere to a supported planar bilayer with mobile ligands, or to a planar substrate with immobile ligands, as illustrated in a, as shown in We employ a statistical-mechanical model that has been widely used to study both the dynamics  and equiκ is the bending rigidity of cell membrane, which governs the elastic deformation of the cell membrane. Here We set the lattice size proteins . Then, bnding is ℋR−L=∑iVbi of cell membrane. To capture the protein affinity for lipid raft, we introduce the energy gain In our model, only the cell membrane contains lipid raft. Each raft patch is represented by a square lattice of size rafts is ℋr−p=−ua∑u for nearest-neighbor raft patches. The total raft-raft contact energy is then described by  theory to study the phase behavior of adhesion system with planar supported membrane containing mobile ligand molecules, as detailed in the Supporting Information (SI). Briefly, we first introduce the grand-canonical Hamiltonian, as given by e system , we can u, the membrane is in a homogenous state with lipid rafts distributed more or less uniformly within the cell membrane. At large values of u the rafts can coalesce into mesoscopic domain and the system undergoes phase separation. The transition between the homogeneous and phase-separated state occurs for Before exploring the interplay between receptor-ligand binding and raft domain formation, we first consider a limiting case of rigid and planar membranes , the raft-raft contact energy u for the adhesion system to phase separation is increased by the presence of receptors, i.e., the binding of receptors to ligands immobilized in multiple clusters hinders the formation of large raft domains. This is due to the fact that the coalescence of small raft domains needs to release the receptors that are associated with the rafts and already bound to immobile ligands , K first increases with u and reaches a plateau, then decreases abruptly in the vicinity of phase transition point, and eventually levels off for u much larger than u, there exists many separate and small raft domains, some of which have no opposing ligand clusters and the associated receptors thus have no chance to bind ligands. As u increases, the rafts coalesce into less but large domains, and the percentage of those excessive receptors decreases, leading to an increase in K. Once each of the multiple ligand clusters is linked to a large raft domain via receptor-ligand complexes, K remains unchanged with u until the system is brought close to the transition point (i.e., K decreases rapidly since there will be more unbound receptors associated with the one single raft domain of size larger than the apposing ligand clusters. The abrupt change in K suggests that K is an indicator of phase separation for the cell-substrate adhesion systems with multiple immobile ligand clusters.We further analyze the dependence of receptor-ligand binding constant of rafts  and confof rafts . The fleu at the phase transition point increases with receptor concentration K decreases with the raft-raft contact energy u and starts to levels off as u becomes even larger than the value K is caused by the energetic penalty paid for the receptors within lipid-raft domains in order to bind to substrate-immobilized ligands outside of the region apposing the raft domains. The results for randomly distributed ligands in u and the receptor-ligand binding constant K is greater for randomly-distributed ligands than for uniformly-distributed ligands, given the other parameters are the same in both cases. The difference in K can be attributed to local aggregation of the randomly-distributed ligands that costs less loss in both translational entropy of the rafts and conformational entropy of the membrane upon receptor-ligand binding. Once the receptors bind strongly to randomly immobilized ligands, the coalescence of rafts associated with those receptors becomes expensive. We then consider the adhesion systems with ligands uniformly or randomly immobilized on the substrate. We’ve performed MC simulations for the two cases with ligand concentration As mentioned in Introduction, there is a discrepancy regarding the interplay between receptor-ligand binding and lipid raft coalescence in adhesion experiments with mobile  and immoWe’ve investigated cell-substrate adhesion mediated by the binding of cell adhesion receptors to ligands that are either anchored to a substrate-supported planar lipid bilayer or directly immobilized on the flat substrate by means of MC simulations and MF calculations based on a classical statistical mechanical model. The model takes into account shape fluctuations of the cell membrane and weak coupling of adhesion receptors to lipid rafts within the cell membrane. We focused on how the ligand mobility plays a role in the interplay between the receptor-ligand binding and raft domain formation. In the biologically relevant range of model parameters, we find that, for the adhesion systems with mobile ligands, the receptor-ligand binding promotes the coalescence of raft domains, which in turn enhances the binding. The lateral attraction between receptor-ligand complexes induced by the membrane shape fluctuations is responsible for the positive correlation.In the adhesion systems with immobile ligands, we find that the interplay between receptor-ligand binding and raft domain formation depends on the distribution of ligands. For uniformly or randomly immobilized ligands, their binding to raft-associated receptors disfavors the aggregation of rafts and vice versa. For substrate-immobilized ligands in clusters, the receptor-ligand binding and raft domain formation can be mutually beneficial or not depending on whether there exists one single or multiple clusters of immobile ligands. The interplay can be understood by considering the loss in membrane configurational entropy and the raft translational entropy upon binding. Our findings not only reveal that ligand mobility and distribution are important physical factors in cell-substrate adhesion, but also help to explain the seemingly contradictory results regarding the interplay between R-L binding and raft heterogeneities in cell-substrate adhesion experiments , where t


The COVID-19 pandemic has imposed serious challenges in multiple perspectives of human life. To diagnose COVID-19, oropharyngeal swab (OP SWAB) sampling is generally applied for viral nucleic acid (VNA) specimen collection. However, manual sampling exposes medical staff to a high risk of infection. Robotic sampling is promising to mitigate this risk to the minimum level, but traditional robot suffers from safety, cost, and control complexity issues for wide-scale deployment. In this work, we present soft robotic technology is promising to achieve robotic OP swab sampling with excellent swab manipulability in a confined oral space and works as dexterous as existing manual approach. This is enabled by a novel Tstone soft (TSS) hand, consisting of a soft wrist and a soft gripper, designed from human sampling observation and bio-inspiration. TSS hand is in a compact size, exerts larger workspace, and achieves comparable dexterity compared to human hand. The soft wrist is capable of agile omnidirectional bending with adjustable stiffness. The terminal soft gripper is effective for disposable swab pinch and replacement. The OP sampling force is easy to be maintained in a safe and comfortable range (throat sampling comfortable region) under a hybrid motion and stiffness virtual fixture-based controller. A dedicated 3 DOFs RCM platform is used for TSS hand global positioning. Design, modeling, and control of the TSS hand are discussed in detail with dedicated experimental validations. A sampling test based on human tele-operation is processed on the oral cavity model with excellent success rate. The proposed TOOS robot demonstrates a highly promising solution for tele-operated, safe, cost-effective, and quick deployable COVID-19 OP swab sampling. I.The outbreak of COVID-19 pandemic leads to profound challenges in people’s daily lives in different fields lastingly and globally At the forefront of combating COVID-19, oropharyngeal viral nucleic acid (VNA) detection is critical to identify potential patients for their timely diagnosis, effective quarantine, and dedicated treatment To minimize the infection risk and reduce the job-related emotional and physical burden among medical staffs, robotic sampling is a promising solution to this challenge Although pioneering efforts have been made to apply robotic technology in OP/NP swab sampling, there are two major concerns about existing OP/NP swab robots. First, the safety concern towards the testee is evident when a bulky and rigid robot is manipulated inside the narrow oral cavity with delicate soft tissue. Second, the dexterity of the terminal end-effector is highly limited with most robots only employing a one-directional swab insertion and retraction. Compared to human operators, existing robots are significantly inferior in terms of safety, user comfort, manipulation dexterity, and potential sampling completeness.To tackle the above challenges, soft robotics technology developed in recent years provides an avenue for safe and effective swab sampling enabled by its inherent compliance and simplified system complexity In this work, we present soft robotic technology is promising to achieve robotic OP swab sampling with excellent swab manipulability in a confined oral space and works as dexterous as existing manual approach. A teleoperated oropharyngeal swab (TOOS) robot is developed, which is constructed by two components, namely the TStone Soft (TSS) hand and a dedicated remote center of motion (RCM) platform. The sampling dexterity is enabled by the TSS hand, consisting of a soft wrist and a soft gripper, designed from human sampling observation and bio-inspiration. TSS hand is in a compact size, exerts larger workspace, and achieves comparable dexterity compared to human hand. The soft wrist is realized by a multi-backbone continuum soft robot with omnidirectional bending and linear elongation/contraction. The stiffness of the soft wrist is pre-adjustable to allow both safety insurance and forceful interaction based on the task requirement. A two-fingered soft gripper is designed to pinch and release the disposable swab, thus facilitating swab replacement. The TSS hand is mounted at the terminal of a 3-degree of freedom (DOF) RCM platform to enable the swab to approach the mouth cavity of the testee during global positioning. An intuitive tele-operation controller is developed to enable real-time teleoperation of the OP swab sampling process, guided by the visual feedback from the camera mounted at the tip of the TSS hand. A hybrid motion/stiffness virtual fixture is designed to ensure the sampling force within the comfortable sampling range. Dedicated experiments have validated the efficacy of the tele-operation control, variable stiffness capability, safe interaction during sampling, human-assisted swab replacement, and complete sampling process in a human user demonstration. The system can be applied to versatile OP swab sampling scenarios with manual sampling comparable dexterity using disposable swabs, which provides a promising solution to reduce face-to-face sampling infection risk of the medical staff.1)A TOOS robot is presented for safe and effective OP swab sampling using existing disposable swab teleoperated by medical staff.2)A novel TSS hand is proposed, which is one of the most dexterous robotic hands dedicated to OP swab sampling using disposable swabs. TSS hand achieves human hand comparable swab manipulation dexterity. The wrist stiffness can be pre-adjusted based on the task requirement and weight of terminal components.3)A teleoperation controller with a novel hybrid motion/force virtual fixture (H-VF) is designed with the consideration of real-time motion teleoperation based on visual feedback and haptic constraint. Sampling safety and comfort can be ensured by the dedicated H-VF constraints.The highlights of the contribution are as follows.The remaining of this paper is organized as follows: II.This section introduces the overall system design of the proposed tele-operated sampling system. The design intention is to replicate the physical joints and sensory perception of a human operator that are involved in manual sampling process.A.To derive our robot design, we investigated how well-trained healthcare workers perform the OP swab sampling. By observing manual sampling process, there are physically three main functional components B.Following the human sampling study, the three physical maneuvers are intended to be achieved by two robotic parts. A 3-DOF RCM platform functions as the human arm to globally position the terminal components approaching the testee The platform provides a global positioning of the terminal TSS hand. The three DOFs distribution is illustrated in After the global positioning, the RCM platform is fixed with the TSS hand robot. After the orientation about the RCM is confirmed, C.The major challenge is to achieve the human hand comparable swab manipulation dexterity, as shown in As for the soft wrist design, it is intended to achieve multi-directional bending as dexterous as a human wrist in a confined space. Besides, the stiffness of the wrist is better to be adjustable to ensure both sampling safety and forceful interaction. The multi-backbone continuum soft robot is a good candidate to serve this intention. The body of the wrist is composed of two nested backbones in an origami structure, with one backbone functions as stiffness tuning backbone and one backbone serves as motion actuation backbone The actual prototype pictures of the TSS hand are shown in Enabled by the soft wrist and soft gripper, TSS hand is one of the most dexterous robotic hands for OP swab sampling with human hand comparable dexterity. Major design parameters of the TSS hand are provided in D.We integrated a camera to provide the human eye’s visual feedback and a haptic device to provide the human hand’s haptic feedback. The camera is a commercially available 5 mega-pixel product, which works with an LED, as shown in III.To achieve effective teleoperation of the TSS hand, the hand model needs to be derived. For the soft gripper, we adopt the on/off control for swab grasping and releasing. For the universal soft wrist, we have to derive the kinematics model from the actuation space to the task space for forward/inverse kinematics-based tele-operation. Besides, the stiffness of the universal soft wrist can be calibrated as a function of the pneumatic input, allowing pre-adjustment of its stiffness in the controller.A.Firstly, we derive the robot-specific kinematics which maps the length of the driving cables to the major parameters of the robot configuration space. The position of the robot is quantified by the point on the centerline, as illustrated by the red dashed line in The length of centerline Considering that the final position of the gripper is of a distance After the forward kinematics derivation, we derive the inverse kinematics of the TSS hand. The basic concept is using the position of gripper to derive the length of the three driven cables. To derive the inverse kinematics, we first derive the configuration parameters The length of each individual driving cable is then calculated as follows:B.The stiffness of the universal soft wrist can be adjusted by the pneumatic input of the inner pneumatic backbone. The larger the input pressure, the larger the stiffness of the wrist. In this work, the relationship between the axial stiffness  for the tele-operation control.A.As shown in The RCM platform controller is embedded in an onboard computer and the motor drivers are connected via CAN-bus communication. The controller is designed to run on the Windows operating system with a dedicated graphical user interface as shown in B.In terms of the TSS hand teleoperation, a TSS controller is designed to enable point-to-point motion control from master to slave system. A motion scale factor The logic of the TSS controller is illustrated in the middle section of the After that, the robot motion command is processed by the hybrid virtual fixture (H-VF) controller.The hybrid motion/force virtual fixture is illustrated in In terms of hardware realization, the TSS robot controller is built on a laptop with MATLAB on the Windows operating system. The cable is driven by three servo motors, controlled through the USB serial port.C.In terms of haptic constraint for operator, the constraint force is used to constrain the operator’s motion to ensure the motion of swab within the region of hybrid virtual fixture. The haptic constraint force is calculated by the consideration of both motion constraint and stiffness constraint of robot. The motion virtual fixture provides the constraint force The stiffness virtual fixture constraint force The overall constraint force, Finally, the force is transferred to the master system to function as the operation haptic constraint force as:For the haptic constraint realization, the haptic device communicates with TSS controller through UDP protocol.D.The stiffness of soft wrist can be pre-adjusted towards different tasks. There are two major influential factors to the stiffness value. One is the desired interaction force. The smaller the interaction force is required, the smaller the original stiffness of the wrist should be. The second factor is the open-loop motion control accuracy and kinetic stability. The larger the stiffness of the wrist, the higher the teleoperation accuracy and kinetic stability, because the higher stiffness will reduce the passive deformation result from the weight of terminal components. Usually, the stiffness value is a tradeoff between these two factors for the desired task.In this sampling task, the stiffness of our used disposable swab is sufficiently compliant to ensure the sampling safety, which will be evaluated in the experimental section. Thus, the stiffness of the wrist is majorly determined by the motion accuracy consideration. A relatively high stiffness value will provide a more accurate tele-operation. The specific stiffness value can be adjusted in the upper left corner of the HMI as shown in E.To tele-operate the robot effectively, the above-discussed control is operationally realized by a dedicated HMI, as shown in V.This section provides the comprehensive experimental validation of the whole proposed TOOS sampling system, including the teleoperation efficacy validation, swab terminal sampling force validation, sampling success rate validation, and human user demonstration.A.The experiment setup to validate the tele-operation efficacy is depicted in TSS hand achieves a human hand comparable workspace and is capable of dexterous omnidirectional bending within the workspace. As shown in The tele-operation performance is presented in To evaluate the accuracy performance of the tele-operation, we recorded the motion of the human hand by the haptic device, the trajectory output of the virtual fixture controller, and the captured real motion of the TSS hand in the teleoperation process. The accuracy of the tele-operation can be analyzed by the comparison of these three trajectories.As shown in Then, we compared the virtual fixture output trajectory with the TSS hand tip trajectory. The trajectory point cloud comparison is depicted in A similar comparison was made between the virtual fixture output trajectory and the swab tip real trajectory. The point cloud of these two trajectories is depicted in The effective sampling forces in both axial and lateral directions were measured under different input pressures with the swab pinched by the TSS hand, as shown in B.The second experiment were performed to determine the variable stiffness model of the TSS hand and to validate the force exertion safety of robotic sampling. Firstly, we measured the change in the lateral and axial forces of the TSS hand, specifically the soft wrist, with respect to the deflection at different pneumatic inputs to obtain the empirical relationship between the stiffness and the pneumatic input. Then, we measured the stiffness of the swabs individually. Three kinds swabs with different stiffness in plastic, wood, and iron material were used in this experiment. Finally, the effective sampling stiffness was measured and compared with the modeling result. Results of the relationship between stiffness and pressure are depicted in Furthermore, in a real sampling process, testee sometimes will cough and there is a human-robot collision potential. The adaptable stiffness of TSS hand and its inherent compliance also provide human-robot collision safety protection.C.To evaluate the sampling success rate, a sampling test on an oropharyngeal phantom model was performed using the TOOS robot and a plastic swab. The system setup is illustrated in For the stiffness pre-adjustment, the stiffness was pre-adjusted to the maximum level with 90 kPa input pressure.Firstly, the RCM platform with the swab attached to the TSS hand was placed near the mouth of the phantom model. Then, the RCM The results prove that the high sampling success rate was ensured by the vision feedback-based teleoperation with a dexterous TSS hand.As for the durability test, we have tested the motion accuracy and grasping robustness after 50 rounds of random sampling cycles. The prototype TSS hand remained dexterity in wrist motion and grasping robustness in swab picking without obvious difference from its original state. We have repeated this test two months after the original assembly of TSS hand, and TSS hand is still effective and provides similar performance to its original state, which validates the durability of the prototype TSS hand. Further durability enhancement can be achieved by material refinement for product level TSS hand fabrication.D.To test the real-time sampling force and the effectiveness of VF constraint, a sampling force experiment was processed as shown in E.Algorithm 11:Sampling Preparation and TSS Hand Disinfection▹ The testee takes a seat and the operator turns on the TOOS robot as shown in 2:Testee-assisted Swab Mounting▹ Testee provides the swab to the TSS hand and the hand grasps the swab firmly as shown in 3:Locking TSS hand4:Swab Insertion and VF Range Selection▹ 5:Tele-operated Sampling▹ Tele-operation is applied to collect the sample from the OP tissue, as shown in 6:Locking TSS Hand7:Swab Exertion▹ 8:Testee-assisted Swab Collection▹ The testee is required to collect the swab, as shown in After the sampling safety and effectiveness validation, we presented real human user sampling to demonstrate the specific steps of the sampling process. The system setup is depicted in The whole sampling process was performed without report from the human user of any uncomfortable contact generated by the robot. There were three operators involved in the tele-operation sampling, with one well-trained Doctor and two robotic researchers. The Doctor who had jointed real COVID-19 OP swab sampling before the tele-operation test and had experience in tele-operated medical device. The Doctor equips well-trained knowledge on the OP swab sampling and experience on the manual sampling strategy. Two robotics researchers have no real OP sampling experience, and one of them has robot tele-operation experience. After a rapid overhand operation, all the three operators can understand and grasp the operation method of the tele-operation system. The swab can be tele-operated at will by the operators. The VF constraint was also acceptable for all three operators to restrict their over large motion.The overall sampling time is around 30 seconds for our OP sampling robot. The human sampling time is around 5 to 10 seconds. Voice communication time is around 10 seconds for testee to fit the position and prepare for sampling. In terms of the swab manipulation, swab collecting the specimen after insertion, the consumed time are quite similar between manual and robot operation. The major difference is at the insertion and extraction speed by the RCM platform, in which the maximum speed is restricted. This speed can be enhanced by replacing a faster insertion and extraction mechanism. The conversation between medical worker and testee can be achieved by the integrated microphone and audio devices. The swab picking, releasing, and collection can be achieved with simple human assistance.VI.In this paper, we present soft robotic technology is a viable solution for safe and effective robotic OP swab sampling. Based on human sampling observation, we concluded three physical interaction components  and two sensing components  were mainly involved in the manual OP sampling. The arm motion is easy to be replaced by robot arm or multi-DOF robotic mechanism. Thus, we developed a 3-DOFs RCM platform to replace the human arm to provide global positioning of the terminal sampling equipment. However, building a robotic hand for dexterous swab manipulation in a confine space is challenging. To tackle this challenge, a novel TSS hand consisting of an universal soft wrist and a soft gripper was proposed to replace the human wrist and human hand. TSS hand is one of the most dexterous soft hand dedicated for disposable swab manipulation and provides human hand comparable dexterity and workspace. The stiffness of the soft wrist can be further pre-adjusted by pneumatic input to ensure both safe and forceful interaction. We applied a teleoperation controller with hybrid virtual fixture constrain for the sampling control. Comprehensive experiments were performed to validate the function of the sampling system, including accuracy of the teleoperation framework, variable stiffness of the TSS hand, and operation safety of robotic sampling. The soft robotics-enabled OP sampling system using existing disposable swab demonstrates promising potential to automate OP sampling process with excellent safety guarantee for both medical staffs and testees.In the future work, we will be seeking ethics approval to perform in-vivo test using our OP sampling system, further refining the TSS hand, integrating sensors to detect contact of the specimen, detect the oral configuration in real-time, refining the hybrid virtual fixture controller, and transferring the TSS hand to two collaborative arms for dual-arm manipulation. In terms of disinfection, disposable shielding cover and UVC sterilization will be considered. Furthermore, the teleoperation controller can be improved by integrating computer vision assistance and artificial intelligence enabled by human behavior learning.


The regulation of gene expression has been studied for decades, but the underlying mechanisms are still not fully understood. As well as local and distant regulation, there are specific mechanisms of regulation during development and physiological modulation of gene activity in differentiated cells. Current research strongly supports a role for the 3D chromosomal structure in the regulation of gene expression. However, it is not known whether the genome structure reflects the formation of active or repressed chromosomal domains or if these structures play a primary role in the regulation of gene expression. During early development, heterochromatinization of ribosomal DNA (rDNA) is coupled with silencing or activation of the expression of different sets of genes. Although the mechanisms behind this type of regulation are not known, rDNA clusters shape frequent inter-chromosomal contacts with a large group of genes controlling development. This review aims to shed light on the involvement of clusters of ribosomal genes in the global regulation of gene expression. We also discuss the possible role of RNA-mediated and phase-separation mechanisms in the global regulation of gene expression by nucleoli. Nucleoli are the largest organelles in nuclei. They are not separated from chromosomes by any kind of membrane and potentially could shape contacts with chromosomal regions in interphase cells either without any particular order, or in some order to attain structural or functional features. If ordered, these contacts should be re-established in the course of cell division and epigenetic mechanisms may be involved. In interphase chromosomes, chromatin forms loops of different sizes that are required for both the compaction of chromosomes and for establishing a regulatory network. The close contacts between nucleoli and the chromosomal DNA were demonstrated by the co-isolation of chromosomal regions that are rather strongly attached to nucleoli during the isolation of nucleoli preparations . HoweverDrosophila genomes. Of particular interest, the novel data suggested a role for nucleoli in differentiation. Localized heterochromatization of rDNA genes initiates the appearance of condensed chromatin structures in different genomic regions coupled with transcriptional activation of differentiation genes and the loss of pluripotency of embryonic stem cells , dense fibrillar component (DFC), and the granular component (GC) . The cluSome rDNA clusters are silent and form constitutive heterochromatin and are not associated with nucleoli . Active Drosophila Pol I regulatory complex includes Under-developed (Udd) and TAF1B factors. Damaging udd or TAF1B leads to a reduced number of germ stem cell clones that produce differentiating cysts over time . Topological-associated domains (TADs) in ESCs are similar in different cell types and the chromatin is generally less condensed . During  repeats . In the  repeats . The ana repeats . Interes repeats . It is pin vivo origin of DSBs is associated with transcription. However, Pleiades are only characteristic of active rDNA clusters that possess the UBF mark. It follows that a high level of DNA breakage inside the nucleoli should be accompanied by a high level of DNA repair  induced by exogenous agents, e.g., ionizing radiation . DSBs ocA repair .The presence of hot spots of DSBs in rDNA explains the fact that there are 166 DNA-damage response (DDR) proteins found in the nucleolus . Among tUpon proteotoxic insults, such as proteasome inhibition or heat shock treatment, nucleolar aggresomes are formed within the nucleolus in nucleolar cavities and intranucleolar bodies . SimilarNucleoli are shaped by the most conserved DNA sequences and thus, could potentially serve as markers of cellular longevity and aging mechanisms . The nucDrosophila and yeast, there is only low rDNA methylation and so other mechanisms of aging must exist beyond rDNA methylation.It has been suggested that changes in cytosine-5 methylation within CpG dinucleotides sites across the genome can be used to predict human chronological age, as well as aspects of biological age . HoweverrDNA genes are hot spots of DNA damage, and they often make intra- and inter-chromosomal contacts with different genomic regions that also possess hot spots of DSBs. These rDNA features lead to a high potential for translocations with different chromosomal regions, as well as with other rDNA clusters . The latDrosophila polytene chromosomes was found many years ago (Deptera were described later (Evidence of the role of nucleoli in differentiation, aging, and cancer raises questions on the nature of the underlying mechanisms by which rDNA clusters regulate different cellular processes. From a general point of view, there are two possible ways for such regulation to occur. One is the regulation by factors that act at a distance, e.g., non-coding RNAs or regulatory proteins that are dependent on the expression of rDNA genes. The second possible way is through direct contacts of rDNA clusters with particular sets of genes by the formation of a net of nucleoli-mediated 3D chromosomal structures. The first microscopic evidence in favor of the formation of reproducible contacts of nucleoli with specific bands in ears ago . More exed later . Then, med later . HoweverThe high-resolution Hi-C and 4C approaches were used to more precisely localize the patterns of rDNA contacts in human cells . About 1The increased resolution confirmed the role of direct contacts of nucleoli with particular genes. First, the rDNA contacts are dynamic and their pattern changes during differentiation or in response to physiological stimuli.Secondly, these changes in the contacts correlate with the changes in the expression of rDNA-contacting genes. Interestingly, in the lymphoma cells, gene expression changes at the rDNA-contacting loci include genes controlling B-cell differentiation, cell growth, and metabolism . In HEK2Drosophila, the contacting sites are enriched with repressive chromatin marks (In mice, the nucleolus may act as a hub for the location and regulation of repressive genomic domains, whereas nuclear speckles are hubs of the location and regulation of active genomic domains . These fin marks , 2020.The depletion of Pol II and enrichment with repressive H3K9me3 marks and the binding sites of the transcriptional repressor ZNF274 suggest the presence of silent chromatin at rDNA-contacting sites . At the In light of the above, we conclude that both active and repressed chromosomal regions shape the contacts with nucleoli. We speculate that both active and silent rDNA clusters could spread the corresponding chromatin state to the chromosomal regions that make contact and, thus, by these mechanisms, nucleoli participate in the organization of both active and repressed hubs in nuclei during differentiation. This conclusion is supported by the detection of conspicuous rDNA contacts in different human cell lines in 5–50-kb regions marked with active H3K27ac marks that may correspond to super-enhancers ; Figure DUX4 gene cluster in the sub-telomeric region of chr4 (DUX4, which is required at the two-cell embryo stage, specifies a transcription factor that activates hundreds of endogenous human genes (FANK1 gene (There are regions of frequent rDNA contacts that span about 100 kb in length and cover the silenced genes. One example is the  of chr4 . Heat sh of chr4 . DUX4, wan genes . At latean genes . The datNK1 gene .Different human cell lines possess overlapping sets of rDNA-contacting genes that exhibit conserved rDNA contacts. For example, in HEK293T, K652, and hESM01 cells, the same set of about 500 genes frequently shape the contacts with rDNA .Gene ontology searches suggest that the overlapping genes are involved in development and morphogenesis. About 100 of these genes  are highDUX4 genes, LINE1 transcripts are required (The association of nucleoli contacts with silenced or activated genes suggests the involvement of rDNA clusters in the global regulation of gene expression. Nevertheless, although the nucleoli may play a major role in the regulation of gene expression regulation, they cannot work alone. Therefore, nucleoli contacts are necessary but not sufficient for such regulation. There are likely many other players in the global regulation of gene expression, e.g., for the silencing of required . It is crequired  confirm There are three major classes of rRNA genes in mammalian cells: silent, inactive, and active . Silent Active rDNA clusters organize nucleoli and rebuild them after each cell cycle . UBF, whNucleoli in their genomic contacts prefer some epigenetic marks, e.g., active H3K27ac marks . At presIn general, all genomic repeats could generate phase separations . The triDrosophila genes, the multiple nucleoli contacts are located in the center of a bubble around which the main chromatin loops are formed (The cognate phase-separated structures on chromosomes could promote the interaction between condensates of the same nature, including nucleoli interactions. The regions of inter-chromosomal rDNA contacts may compete with the local intra-chromosomal contacts and displace them. In e formed . The forIn vitro droplet reconstitution with purified fibrillarin and nucleophosmin showed that the proteins readily form condensed liquid droplets that exhibit biophysical features similar to those of intact nucleoli (Recently, it was demonstrated that fibrillarin, the dense fibrillar component constituent, and nucleophosmin, the scaffold protein of the granular component, are implicated in nucleation, including the tripartite organization of nucleoli . In direnucleoli .The nature of the nucleolus, which is made up of phase-separated compartments itself, suggests a potential role in the long-range dynamic interactions in the nucleus because liquid-liquid phase separation physically allows the rapid movement of components into and within the dense phase . These iNucleoli play many important roles beyond the biogenesis of ribosomes, including shaping of the nuclear architecture and regulation of DNA repair, differentiation, chaperone-like functions, RNP formation, diverse stress responses and others. The abnormal function of nucleoli leads to cancer genesis and diseases. Recently, it was demonstrated that inter-chromosomal contacts of nucleoli are involved in the regulation of global gene expression. The nature of these contacts and their role in development remains to be elucidated. It is not clear how rDNA inter-chromosomal contacts affect the local intra-chromosomal 3D domains. The contacts may be important for other functions of the nucleoli, including DNA repair and stress responses. The key areas for study in the future include determining the underlying molecular mechanisms of nucleoli function as a driver of nucleoli’s role in cellular development and the response to environmental stimuli, the RNA-mediated mechanisms involved in recognizing target genes, and the phase-separation mechanisms in the formation of nucleoli and their dynamic 3D structures.NT wrote the manuscript. YK developed software for image and statistical analysis. Both authors contributed to the article and approved the submitted version.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.


Ectopic growth of these eggs causes fatal granulomatosis and cirrhosis of the liver. The parasites ingest nutrients from the host blood plasma by using nonspecific and specific transport via their body surface and alimentary tracts. It is especially important for the female adults to obtain lipid molecules because they synthesize neither fatty acids nor sterols and yet produce egg yolk. Low-density lipoprotein receptors have been identified in the body of the Schistosomes but their functions in the parasite life cycle have not clearly been characterized. On the other hand, CD36-related protein was identified in the body and the eggs of Asian blood fluke, Schistosoma japonicum, and characterized as a molecule that mediates selective uptake of cholesteryl ester from the host plasma high-density lipoproteins (HDLs). This reaction was shown crucial for their eggs to grow to miracidia. Interestingly, abnormal large HDL generated in lack of cholesteryl ester transfer protein (CETP) is a poor substrate for this reaction, and, therefore, CETP deficiency resists pathogenic ectopic growth of the aberrant parasite eggs in the liver. This genetic mutation is exclusively found in East Asia, overlapping with the current and historic regions of Schistosoma japonicum epidemic, so that this infection could be related to high prevalence of CETP deficiency in East Asia.Schistosomiasis is a life-threatening parasitic disease caused by blood flukes, Schistosomes. In its intestinal type, the parasites reside in visceral/portal veins of the human hosts and lay eggs to excrete in feces  Schistosoma mansoni (S. mansoni) in Africa and South America, Schistosoma japonicum (S. japonicum) or its subtypes in East Asia (Schistosoma haematobium (S. haematobium) in Africa and Middle East. The former two cause intestinal schistosomiasis where the adult parasites reside in portal/visceral veins of the host animals and lay eggs which penetrate into intestinal lumen to be excreted in feces. The latter causes urogenital schistosomiasis where the worms infect in pelvic vein and the eggs penetrate into urinary tract and genital organs to be excreted    or boronne (DiI) . Anothereceptors . Howevereceptors . No funceceptors .in vivo  among lipoproteins  in certaGeneration of CE in HDL is one of the driving forces to remove cell cholesterol  to play The patients with CETP deficiency were first described in Japan in 1985 as the cases with hyperalphalipoproteinemia . Its gen–10.8% among the mainland Chinese , which are mostly infectious in these situations. The former cases are found in relatively isolated communities of the descendants from earlier settlers. Typical examples are familial hypercholesterolemia accumulated in French Canadians , in Afri disease , mycotic disease  likely c disease , filovir disease , and rab disease .Majority of the patients with CETP deficiency accumulated in East Asia may be limited to one or two type(s) of mutations but further diversity of mutation is also found in the region. In addition, the region with high prevalence of the mutants is so large in East Asia beyond considering founder’s effect. No specific settler family can be conceivable to account for such large descending population affected. The only exception is extreme accumulation of the mutant int14A in Omagari, Japan, which can be a potential case of the local “founders’ effect” . HoweverThe reason for poor reactivity of the HDL of CETP deficiency is not clear at this moment. CETP is a plasma protein that mediates nondirectional transfer of hydrophobic core lipids like CE and TG between lipoprotein particles . As CE iS. japonicum infection is either currently still endemic or it has been or potentially been highly endemic in the historic records (Schistosomiasis japonica, i.e., hepatic granulomatosis and cirrhosis in the mouse model (The regions the mutations are found with high prevalence of CETP deficiency largely overlap with the areas where  records ; Table 2 records . The higse model , it is cS. japonicum expresses CD36RP in the adults and their eggs, which mediates selective CE uptake from the host plasma HDL as a pathway for the parasite to ingest lipid nutrients (S. japonicum infection can be one of the factors to screen CETP deficiency in East Asia. Because the ectopic embryonation is the major fatal complication of schistosomiasis, the CD36RP pathway is an important potential target to inhibit for prevention of the fatal complication of this disease (S. japonicum so that S. mansoni should be investigated to find whether the findings are more general. Further studies are required to understand association of S. japonicum infection and CETP gene mutation based on genome-wide analysis for evolutional backgrounds of the human genes in certain regional or ethnic groups, like the recent findings of copy number variants in Melanesians selected from Denisovans and Neanderthals (utrients . This reutrients , so that disease . Inhibitderthals  or lack derthals .


Animal model studies and first clinical trials have demonstrated the safety and efficacy of the mesenchymal stem cells’ (MSCs) transplantation in stroke. Intra-arterial (IA) administration looks especially promising, since it provides targeted cell delivery to the ischemic brain, is highly effective, and can be safe as long as the infusion is conducted appropriately. However, wider clinical application of the IA MSCs transplantation will only be possible after a better understanding of the mechanism of their therapeutic action is achieved. On the way to achieve this goal, the study of transplanted cells’ fate and their interactions with the blood–brain barrier (BBB) structures could be one of the key factors. In this review, we analyze the available data concerning one of the most important aspects of the transplanted MSCs’ action—the ability of cells to cross the blood–brain barrier (BBB) in vitro and in vivo after IA administration into animals with experimental stroke. The collected data show that some of the transplanted MSCs temporarily attach to the walls of the cerebral vessels and then return to the bloodstream or penetrate the BBB and either undergo homing in the perivascular space or penetrate deeper into the parenchyma. Transmigration across the BBB is not necessary for the induction of therapeutic effects, which can be incited through a paracrine mechanism even by cells located inside the blood vessels. Ischemic stroke incidence and mortality rate, as well as the proportion of post-stroke patients remaining disabled stay at an unacceptably high level worldwide . CurrentTo introduce transplantation of MSCs into clinical practice, it is necessary to understand the mechanisms of their therapeutic action better. Several mechanisms underlying the therapeutic effects of MSCs have been proposed, among them paracrine action, direct interaction with other cells, and substitution of dead/damaged parenchymal cells after homing inside the tissue and differentiation ,16. ParaWhile the direct replacement of damaged neural cells by transplanted MSCs after stroke is debatable, their paracrine effects in the same pathology are well established. MSCs secrete a wide range of different factors and extracellular vesicles that may have an important role in the regeneration of brain tissue and restoration of brain functioning . Anti-inSeveral routes of MSC transplantation in stroke, including the intra-arterial (IA), intravenous (IV), intraperitoneal, intracerebral, intraventricular, intrathecal, and intranasal delivery were tried and showed therapeutic efficacy ,31. HoweAfter IA transplantation, the substitution of the damaged cells by their counterparts differentiating from transplanted MSCs is only possible if the latter penetrate from blood into the brain tissue and undergo homing and differentiation. Direct cell–cell interaction of transplanted MSCs with neurons and glia also requires passing the BBB. On the other hand, paracrine effects can be induced even by cells remaining inside the circulation.In this review, we analyze the available data concerning interactions of MSCs with the BBB components and their ability to cross BBB in vitro and in the experimental stroke models in vivo after IA administration. Analyzing publications describing the in vivo studies, we concentrated on the search of the publications presenting data clearly showing the location of specifically labeled and positively traceable transplanted MSCs within blood vessels or in brain parenchyma. These papers were regarded as the most reliable source of information about the interactions of MSCs with the BBB, the neurovascular unit, and their components, and about the ability of MSCs to cross the BBB. Other works were also considered, but with some reservation.The BBB separates brain parenchyma from the bloodstream and at the same time supports two-way communication between them. It is a unique border consisting of endothelial cells, basement membrane, pericytes, and astrocytes . The bloDamage occurring to the BBB and the NVU plays an important role in the pathogenesis of stroke (comprehensively reviewed in ). The peThough the NVU itself exerts protective effects through secretion of a variety of neurotrophic factors and modulation of the inflammatory immune response ,63, its Recently, it was shown that MSCs can promote their beneficial effects via restoration of the ‘glymphatic’ system. Glial components (end-feet of astrocytes), which are functionally active components of the NVU and provide the outer border of the perivascular space from the side of the brain parenchyma, perform the functions of the central nervous system cleansing and waste exchange, forming the so-called “glymphatic” system . AquaporAnother possible mechanism underlying MSC-mediated BBB repair is their ability to regulate the activity of matrix metalloproteinases  and cardiac (hCMVECs) microvascular endothelial cells, 50% of human bone marrow MSCs integrated into the endothelial layer, inducing endothelial pocketing, rather than transmigrated across it . In addiIn the BBB models employing brain endothelial cells, the integration of MSCs was observed very rarely, and transmigration almost always occurred along the paracellular pathway. Using rat bone marrow MSCs and human BMECs, Lin et al.  found thSeveral possible mechanisms of the induction of transient gaps formation between BBB endothelial cells by MSCs in vitro have been described. Thus, it was shown that medium conditioned by MSCs cultured under hypoxic conditions and containing high levels of VEGF and matrix metalloprotease-9 (MMP-9), induced a sharp increase in the permeability of the BMEC monolayer . The incIt has been reliably proven that VEGF is one of the key factors enhancing BBB permeability under ischemia/hypoxia conditions ,102. VEGMMP-9 plays an important role in disrupting the integrity of the BBB and, as a consequence, increasing its permeability. It has been shown that the level of MMP-9 increases significantly in ischemic, hemorrhagic, and traumatic brain injuries . InhibitThe so-called “zipper mechanism” may be another mechanism underlying the formation of temporary gaps between BBB endothelial cells in the process of their interaction with MSCs. It has been described for human embryonic stem cells-derived MSCs (hES-MSCs) and its essence is as follows. Since both BMECs and hES-MSCs express the same cell adhesion molecules CLN-5, ZO-1, and occluding, their co-cultivation may result in the formation of temporary homophilic and/or heterophilic interactions between the corresponding proteins and formation of tight/adhesive junctions between MSCs and endothelium . This prIt has been shown that the main signaling pathways involved in the processes of cytokine-directed migration of MSCs are PI3K/Akt ,113, RhoSadly, until now no published papers have reported any results of the in vitro experiments describing the transmigration of MSCs across complex models of the BBB comprising not just BMEC monolayer, but other BBB components. Accordingly, there is no complete picture reflecting the mechanisms of MSC transmigration, and the key regulators of this process have been only partly identified. There is urgent need for the application of more complete and relevant in vitro BBB models to MSC transmigration research.Studying the extravasation of MSCs systemically transplanted into animals with experimental stroke is essential for understanding the mechanisms underlying the beneficial effects of cell therapy in this condition. Despite proven therapeutic efficacy of the IV MSC transplantation , the numThe experimental assessment of this process is not an easy task. Part of the published papers present results based on insufficiently reliable methods of identification of transplanted cells. One more problem is that the diversity of the employed experimental approaches impeding the estimation and comparison of the results. Analyzing the literature, we aimed to select studies where the exact location and fate of MSCs after transplantation were clearly revealed and illustrated. The results of these relatively few studies are presented in 4 to 2 × 106, and infusion parameters were slightly different from study to study. In The papers listed in The results concerning the crossing of the BBB by MSCs in cerebral ischemia and stroke are controversial. In all studies included in All studies, where BBB crossing by MSCs was not observed, had two common features: (1) transplantation of human MSCs into rats, and (2) lack of immunosuppression. If immunosuppression was performed, xenogenous human MSCs were visualized in rat brain parenchyma in the peri-infarct zone ,139. NotTraditionally, MSCs are considered non-immunogenic  and wereThe long-term survival of transplanted MSCs, their crossing of the BBB and engraftment in the cerebral parenchyma may be not necessary for providing recovery after stroke. Keimpema et al. have demonstrated that stroke volume reduction can be achieved by early transient presence of intravascularly implanted MSCs at the lesion site, but not by passing of sporadic cells into the brain parenchyma . In all It is well established that infusion of MSC suspension into the brain arterial system in stroke alleviates the symptoms of the disease (discussed in ). The faThe currently available evidence presented in this review suggests that the fates of the transplanted cells after they enter cerebral vascularity can be different . The majThe curative effects induced by cells staying inside blood vessels demonstrate that, in some cases, the paracrine mechanism may be fully responsible for the restorative action of cell therapy in stroke. In this respect, IA infusion of human MSCs into rats with experimental stroke may be a suitable in vivo model for studying the mechanisms underlying the paracrine effects of MSCs at the molecular level.ClinicalTrials.gov site reports several clinical trials where the IA stem cell infusion was utilized. In most of these trials, autologous bone marrow cells were used, and only in one trial, initiated in 2020 and still in the patient recruitment stage, allogeneic MSCs isolated from the umbilical cord are scheduled for transplantation  Most cells just pass-through brain capillaries and presumably to the general circulation. (2) Some cells adhere to the endotheliocytes for up to several days. (3) Other cells adhere to the endothelium, then get through the endothelial layer presumably through intercellular gaps, and home in the perivascular space for no more than several days. Probably they are later destroyed by the microglial cells. (4) Cells adhere to the endothelium, pass through the BBB, and can be found in brain parenchyma for several weeks. We did not find any confirmations of their neural differentiation.Transmigration across the BBB is not necessary for induction of therapeutic effects, though, of course, it may change the parameters of the therapeutic response.Most likely, the transitory presence of the transplanted MSCs in brain blood vessels may trigger a range of therapeutic and restorative responses through paracrine secretion of an array of biologically active molecules in free form or enclosed in extracellular vesicles.Immunosuppression-free transplantation of human MSCs into rat arterial systems may be an in vivo model suitable for studying paracrine effects of MSCs in stroke.


The wide range of industrial applications of flow across moving or static solid surfaces has aroused the curiosity of researchers. In order to generate a more exact estimate of flow and heat transfer properties, three-dimensional modelling must be addressed. This plays a vital role in metalworking operations, producing plastic and rubber films, and the continuous cooling of fibre. In view of the above scope, an incompressible, laminar three-dimensional flow of a Casson nanoliquid in the occurrence of thermophoretic particle deposition over a non-linearly extending sheet is examined. To convert the collection of partial differential equations into ordinary differential equations, the governing equations are framed with sufficient assumptions, and appropriate similarity transformations are employed. The reduced equations are solved by implementing Runge Kutta Fehlberg 4th 5th order technique with the aid of a shooting scheme. The numerical results are obtained for linear and non-linear cases, and graphs are drawn for various dimensionless constraints. The present study shows that improvement in the Casson parameter values will diminish the axial velocities, but improvement is seen in thermal distribution. The escalation in the thermophoretic parameter will decline the concentration profiles. The rate of mass transfer, surface drag force will reduce with the improved values of the power law index. The non-linear stretching case shows greater impact in all of the profiles compared to the linear stretching case. The vast range of technological applications of flow across moving or static solid surfaces has aroused the curiosity of researchers. The vaporisation of liquid coatings, the pulling of filaments through a static liquid, crystallization process techniques, the production of rubber and plastic films, and the nonstop cooling of fibre use these concepts. The research community has been studying various elements of such flows since the emergence of boundary layer models. Vajravelu  introducNon-Newtonian liquids are those that do not follow Newton’s viscosity rule. Shampoos, sauces, pastes, acrylics, colloidal solutions, and ketchup are just a few examples. Because of its rheological uses in chemical and mechanical engineering processes, most fluid mechanics researchers currently focus on this type of fluid. Casson liquid is one of the best non-Newtonian liquids because of its numerous applications in metallurgy, food dispensing, bioengineering, and penetrating activities. Casson liquid is classified as a shear depleting liquid with an indeterminable thickness at zero shear rate. Recently, Gowda et al.  examinedOne of the most challenging difficulties that engineers and companies face is thermal management. The heat is transferred via base liquids. Heat distribution is a problem with these basic liquids. Researchers will add nanoparticles to these common base liquids to increase thermal dispersion and thermal distribution, and obtained fluids are called as nanoliquid. Nanoparticles often comprise oxides, metals, and carbon nanotubes with diameters ranging from 1 to 100 nm. Due to the augmentation in the rate of heat transfer, researchers will pay attention to nanofluids. Recently, Kumar et al.  examinedThermophoresis is a phenomenon that happens when particles separated in vapor are subjected to a thermal gradient and migrate from the hot to the cold zone of the gas. Thermophoresis particles are used in a wide range of engineering and manufacturing purposes, including nuclear reactor safety, thermal precipitation design, and physical vapor confession. Chen et al.  studied Based on the above served literature, the primary aim of the present article is to numerically analyze the thermal and mass distribution of a three-dimensional non-linear extending surface with aluminum oxide based Casson nanofluid in the presence of thermophoretic particle deposition, which has not yet been studied to the best of the authors’ knowledge. Thermophoretic particle deposition facilitates the investigation of differences in mass transfer performance due to modest aluminum oxide percentage changes. The present study is useful in various engineering applications. The governing equations that represent the flow and thermal characteristics with appropriate boundary conditions are formulated. These equations are reduced with suitable similarity variables and numerically solved by using an apt numerical method. Since many analytical and semi-analytical procedures exist to solve these kinds of equations, we used the RKF-45 method to fulfill this gap. The parameters that influence the flow characters are analyzed with respective profiles, and detailed discussions are made for both linear and non-linear cases. The essential engineering aspects are discussed.Consider an incompressible, laminar 3D flow of a Casson nanoliquid in the presence of TPD over a non-linearly stretching sheet. The sheet is moving with uniform velocity The rheological equation of state for an isotropic and incompressible flow of Casson fluid is given by:In the above equation, The geometry of the described problem is illustrated in Boundary conditions –(7), The term Here, n et al. ).The below-mentioned similarity variables are introduced  and (9) into (1)–(6) and simplifying, the following equations are obtained.(1)(2)The proposed problem deals with two different cases based on the following considerations:Where, The thermophysical properties of nanofluid are given :(16)AloThe set of reduced equations stated in Equations (10)–(13) and boundary constraints (14) are solved using the RKF-45 method and the shooting scheme. The obtained equations are higher-order and two-point in nature. To get the solution, we reduced the system of ODEs and boundary conditions into a first-order system by substituting The IVP stated in Equations (20) and (21) are solved by the RKF-45 method, and unknown values are obtained by the shooting scheme by setting step size The fundamental goal of the present section is to analyze the influence of various dimensionless constraints on their respective profiles. The reduced ODEs (10–13) and boundary conditions (14) are numerically solved with RK-45 and shooting schemes. We convert the ODEs into IVP, and the shooting scheme is adopted to obtain the missing boundary conditions. Thermophysical properties of nanoparticle and base liquid are presented in The variation of tion see b. The vaImprovement in the Casson parameter will decline the axial velocity in The thermal distribution is improved with enhancement in the Casson parameter due to an increment in boundary layer thickness.Improved values of the Schmidt number will decline the concentration due to an increase in mass diffusivity.An increase in the values of the thermophoretic parameter affects the concentration profiles due to an increment in the temperature gradient.The rate of mass transfer will decrease with an upsurge in the values of the thermophoretic parameter.The rate of thermal distribution will improve with an increment in the Casson parameter due to an enhancement in the thickness of the boundary layer.The axial velocity and thermal distribution will be more in the case of An incompressible, laminar three-dimensional flow of a Casson nanoliquid in the presence of thermophoretic particle deposition over a non-linearly stretching sheet is examined. To convert the collection of partial differential equations into ordinary differential equations, the governing equations are constructed with appropriate assumptions, and acceptable similarity variables are employed. The simplified equations are solved using software by applying the Runge Kutta Fehlberg 4th 5th order method with a shooting scheme. The graphs are drawn for various constraints, and important engineering factors are discussed in detail. The significant findings of the current study are as follows:


The Adult Day Service Plus Program (ADS Plus) augments the usual care provided by ADS programs by integrating education, referrals, and problem-solving strategies for family caregivers of persons with dementia. Utilizing a mixed-methods, hybrid effectiveness design, we were in the process of conducting a national evaluation of ADS Plus across xx geographically and culturally diverse programs across the U.S. when the COVID-19 pandemic resulted in the shutdown of almost all of the programs participating in ADS Plus. Qualitative and quantitative data collected during the evaluation suggested that a more robust incorporation of implementation domains and measures  may have helped avoid some of the challenges related to staff training, fidelity, and other critical intervention delivery aspects. Incorporating implementation science frameworks and measures as early as possible in intervention design may have helped to overcome some of the challenges experienced in ADS Plus.


Implementation of antenatal clinical guideline recommendations for addressing maternal alcohol consumption is sub-optimal. There is a complete absence of evidence of the cost and cost-effectiveness of delivering practice change interventions addressing maternal alcohol consumption amongst women accessing maternity services. The study sought to determine the cost, cost-consequence and cost-effectiveness of developing and delivering a multi-strategy practice change intervention in three sectors of a health district in New South Wales, Australia.The trial-based economic analyses compared the costs and outcomes of the intervention to usual care over the 35-month period of the stepped-wedge trial. A health service provider perspective was selected to focus on the cost of delivering the practice change intervention, rather than the cost of delivering antenatal care itself. All costs are reported in Australian dollars . Univariate and probabilistic sensitivity analyses assessed the effect of variation in intervention effect and costs.The total cost of delivering the practice change intervention across all three sectors was $367,646, of which $40,871 (11%) were development costs and $326,774 (89%) were delivery costs. Labour costs comprised 70% of the total intervention delivery cost. A single practice change strategy, ‘educational meetings and educational materials’ contributed 65% of the delivery cost. Based on the trial’s primary efficacy outcome, the incremental cost effectiveness ratio was calculated to be $32,570  per percent increase in receipt of guideline recommended care. Based on the number of women attending the maternity services during the trial period, the average incremental cost per woman who received all guideline elements was $591 (Range: $329 - $940) . The average cost of the intervention per eligible clinician was $993 (Range: $640-$1928).The intervention was more effective than usual care, at an increased cost. Healthcare funders’ willingness to pay for this incremental effect is unknown. However, the strategic investment in systems change is expected to improve the efficiency of the practice change intervention over time. Given the positive trial findings, further research and monitoring is required to assess the sustainability of intervention effectiveness and whether economies of scale, or reduced costs of intervention delivery can be achieved without impact on outcomes.The trial was prospectively registered with the Australian and New Zealand Clinical Trials Registry, No. ACTRN12617000882325 (date registered: 16/06/2017).The online version contains supplementary material available at 10.1186/s13012-021-01180-6. Alcohol consumption during pregnancy is associated with adverse obstetric and infant outcomes that can have lifelong social and economic consequences , 2. SpecPublic maternity services are important settings for the provision of antenatal care to a large proportion of pregnant women , 6. InteDespite the increasing use of economic evaluation in health services research, its application to the assessment of the cost and cost effectiveness of practice change intervention strategies is limited  19, 20], 2019, 2Identify, measure and value the cost of developing and delivering a multi-strategy practice change intervention;Report the costs and consequences of a multi-strategy practice change intervention; andDetermine the cost-effectiveness of a multi-strategy practice change intervention in improving antenatal care provider adherence to antenatal care guidelines compared to usual care.The importance of economic evaluation in the context of implementation science and how these analyses can be most efficiently incorporated into decision-making process has been recognised . To addrThe secondary aims for the economic evaluation were to report each of the aims by sector.The practice change intervention trial has been reported by Kingsland et al. . In summOutcome data were collected over a 35 month period from seven-months prior to commencement of the practice change intervention in the first sector to seven-months following completion of the intervention in the third sector . SteppedAn evidence- and guideline-based model of antenatal care was developed to address alcohol consumption by pregnant women . The modA multi-strategy practice change intervention to support the provision of the antenatal model of antenatal care was co-designed with input from health service stakeholders  and Aboriginal health organisations and women, and was guided by an implementation framework –29. The Prior to delivery of the practice change intervention in each of the three sectors, usual antenatal care addressing maternal alcohol consumption during pregnancy was provided . An obseDetails of the approach to conducting the economic evaluation have been reported in the economic evaluation protocol . A trialThe economic evaluation was conducted and reported in accordance with the Consolidated Health Economic Evaluation Reporting Standards (CHEERS) publication guidelines and good reporting practices . AdherenThe economic evaluation was based on the trial primary outcome: the proportion of women at the initial, 27-28 weeks gestation and 35–36 weeks gestation antenatal visits who reported being assessed for alcohol consumption using the Alcohol Use Disorders Identification Test (AUDIT-C) tool, and who received the recommended elements of care  appropriate to their level of risk, as determined by AUDIT-C risk categories for pregnancy . The triAt present, there are no guidelines for costing practice change interventions that aim to improve the implementation of guideline recommendations in health care settings , 34. A rIntervention costs were prospectively identified and measured using a time-driven activity based cost-capture tool . The cosCost data were treated as counts of resource use, weighted by unit costs. The cost for each sector was determined by summing the intervention delivery costs relevant to and coded for that sector. A cost per practice change strategy is reported to demonstrate the investment required for each of the seven strategies and to inform future intervention scale up and sustainability. The intervention was wholly additional to usual care, that is, no usual practice activity was displaced as a result of the intervention. Costs to providers, patients and private care providers (including opportunity costs) were not assessed.The results of the CCA are presented as the total cost of delivering the intervention alongside the range of outcomes reflected in the primary and secondary trial outcomes (consequences). The cost per eligible clinical provider is presented to demonstrate the cost and consequence of the intervention for those intended to provide the evidence-based model of care. Eligible clinical providers were all clinicians within the participating maternity services who provided antenatal care during the intervention period. Eligible clinical providers included midwifery and medical staff as well as Aboriginal Health Workers. It excluded clinicians who were not the primary providers of antenatal care . Eligible clinical providers were identified through rostering and payroll systems obtained from the participating maternity services. Modelled extrapolation of the self-report survey data was conducted to estimate the proportion of all women attending the participating maternity services who received all guideline elements during the intervention follow-up period. This extrapolation enabled estimation of the incremental cost per woman who received all guideline elements, in each sector. The average cost per woman was calculated as the cost of the practice change intervention, divided by the total number of women who are anticipated to have received all guideline elements based on the sample of women surveyed.The trial-based CEA aligned the cost of the intervention against self-reported receipt of all guideline elements of antenatal care. The trial outcomes, reported as odds ratios, were converted to risk differences for inclusion in the CEA, e.g. the risk difference for the primary outcome refers to the percentage point (proportion) increase in the self-reported receipt of all guideline elements of antenatal care. This information was used to generate an ICER.ICERs were calculated by sector to enable reporting of the variation in costs and effect sizes between the three sectors. One-way probabilistic sensitivity analyses assessed the effect of variation in the magnitude of treatment effect using the lower and upper confidence interval limits and variation in costs of intervention components using the lower and upper bounds of staff salaries. Non-parametric bootstrapping was undertaken to derive uncertainty intervals around the estimates for total cost and cost-effectiveness. Results from the sensitivity analyses were visually presented on a cost-effectiveness plane where the joint distribution of incremental costs were plotted against the incremental change in effect size between baseline and follow-up. Refer to Figs. The resources invested to increase compliance with the guideline-based model of care were calculated as being wholly incremental to usual practice. The total cost of the practice change intervention across all three sectors was $367,646 of which $40,871 (11%) were development costs and $326,774 (89%)  were intervention delivery costs. Of the intervention delivery costs, Sector one cost $133,188 (41%) of the practice change intervention costs. Sectors two and three incurred similar proportions of the practice change intervention cost, 30% and 29% respectively. The cost of labour was the main cost driver for the intervention, comprising 70% of the total intervention costs. Refer to Table Of the seven practice change intervention strategies ‘educational meetings and educational materials’ comprised 65% of the total intervention cost, followed by ‘local opinion leaders/champions’ with 18% of the intervention costs. The salary of the clinician midwife educator (CME) was the main cost driver for the ‘educational meetings and educational materials’ strategy. A CME was employed in each sector for the duration of the 7-month intervention. The CME for Sector one was employed at 1.0 full-time equivalent (FTE), the CME for Sector two at 0.6 FTE and Sector three at 0.4 FTE, relative to the number of births in each Sector. The remaining five intervention strategies each incurred between 1% and 8% of the total intervention costs. Refer to Fig. p = <0.001). The increase in receipt of all guideline elements was seen across all three sectors. The average cost of delivering the practice change intervention per eligible clinician was $993 (Range: $640-$1928). Based on the average number of women in the service per month over the trial follow-up period, the extrapolated average cost per woman who received all guideline elements was calculated to be $591 (Range: $329 - $940). Variation in the average cost per woman was associated with variation in the average number of women through each service, per month between sectors. Sector one had a total of 6862 women through the antenatal service during the 21-month follow-up period, an average of 58 women per month reporting receipt of all guideline elements for the duration of the intervention. In comparison, Sector two had an average of 29 women per month reporting receipt of all guideline elements for a 14-month time period and Sector three had an average of 14 women per month for the seven-month time period. Refer to Table Significant intervention effects were found for receipt of all guideline elements . The incremental cost per percent increase in women receiving all guideline elements ranged from $15,951  in Sector one and $5,618  in Sector two. Refer to Table The ICER in the sensitivity analysis was $35,024 , indicating that the ICER was sensitive to variation in labour costs Table Figures This economic evaluation outlined the costs, consequences, and cost-effectiveness associated with the first published randomised controlled trial to examine the effectiveness and efficiency of delivering a practice change intervention to improve the implementation of guideline recommended care for maternal alcohol consumption. The intervention was effective at improving reported receipt of all guideline elements of care. The incremental cost of intervention delivery was calculated to be $326,774. Labour (staff time) was the main cost driver and variation in delivery costs across sectors was associated with design differences in labour time and travel costs for each sector.The average cost over the trial period of delivering the practice change intervention per eligible clinician was $993, and $591 per woman who received all guideline elements. The cost of delivering clinician training was upfront and is not expected to require additional investment beyond the trial horizon. Clinician training modules were developed during the intervention and made permanently available online for staff to access as part of their ongoing clinician training. Further, in an effort to sustain the intervention effect size, implementation strategies were deliberately designed to affect permanent and scalable change within the health system, e.g. the inclusion of specific modules into the state-based e-maternity patient record management system, and performance measures were embedded into the health system. Therefore, these implementation strategies are expected to sustain the effect size post-intervention. As such, the average cost per woman is expected to reduce markedly with continued delivery of this new model of care over time , with increased women receiving antenatal care and with scaling up to involve other maternity services/clinicians. Similarly, with respect to potential ongoing costs  associated with this intervention and maintaining the intervention effect size beyond the trial time horizon.Direct comparison between the results of this and previously reported studies of the cost and cost effectiveness of practice change interventions is not possible given the significant differences in the design and methods of the various studies. Broad comparisons with studies included in previous systematic reviews were also limited as the costs associated with the implementation of the practice change strategies is not often considered , 24, 37.Implementation costs are recognised as an understudied aspect of implementation science , 40. SalAnother strength of this economic evaluation is the identification, measurement and valuation of development costs. That is, once the practice change intervention has been delivered, there are non-recoverable intervention components that remain within each sector. For example, the cost of developing and producing local clinical guidelines, the cost of developing educational materials and the cost of developing site-specific systems level monitoring and accountability measures. Saldana et al. argue development costs are an important consideration in decision making as policy makers must decide ex ante whether to invest in a new model of care and unrecoverable costs must be considered amongst the future benefits . TranspaIt was not possible to calculate an ICER for the cost per additional service user (pregnant woman) who received all guideline elements of care. The study was designed and powered to measure effectiveness at the health sector level, thus precluding this ICER calculation. Given this limitation, the average cost per additional service user (pregnant woman) exposed to the recommended treatment was calculated. Another, limitation of the study was that the ICER was calculated on the assumption that the intervention was wholly additional to usual care, that is, no usual practice activity was displaced as a result of the intervention. Identifying, measuring and valuing the cost of usual care was beyond the scope of the trial and hence a limitation of the analysis. The trial time horizon was 35-months, and as such only upfront and short-term costs to health service providers were included. Similarly, the potential impact of increased referrals to drug and alcohol services and the longer-term benefits of alcohol-harm reduction to society at large, was not captured in this trial and is a noted limitation. Future economic evaluations should endeavour to include these components. The range of costs associated with sustaining changes in provider behaviour and maternal alcohol consumption is complex , and beyThe practice change intervention was effective at improving women’s reported receipt of all guideline elements of care. The incremental cost of delivering the intervention was calculated to be $326,774. To our knowledge, no similar studies have been published in the literature. The economic evaluation provides information for decision and policy makers regarding the cost, cost-consequence and cost-effectiveness of delivering a practice change intervention to support the introduction of a model of care for addressing alcohol consumption by pregnant women. Given the positive trial findings, further research is required to assess sustainability and determine the cost of delivering the intervention at scale and whether economies of scale can be achieved.Additional file 1.


Metal–organic frameworks (MOFs) are hybrid crystalline particles composed of metal cations and organic linkers. Ranging from micro- to nanoscale depending on the preparation conditions, they have achieved a prevalent position among porous materials. The fact that varying either the metal cation or the organic component leads to a wide range of pore sizes and structures has made them very appealing materials in a broad variety of fields, including gas storage, heterogeneus catalysis, separation, imaging, biosensing, agriculture, and biomedicine. By optimizing the internal pore volume, many molecules of different natures can be accommodated within the matrix. For instance, the anticancer drug doxorubicin is well known to enter within iron trimesate MIL-100(Fe) nanoMOF. However, the use of this inclusion complex in biomedicine requires the controlled release of the drug. As reported in one of the articles within this Special Issue [The use of nanoMOFs in the field of biomedicine also requires a good deal of knowledge about the degradation mechanisms of these materials. For instance, MIL-100(Fe) can cause an increased iron concentration in both the liver and spleen, but these levels remain far from being toxic to these organs. Furthermore, urine and feces excrete excess iron after 15 days. Understanding how the structural defects of the particles affect their degradation rate is of pivotal importance to pave the way for their clinical use as delivery systems in biological media. One of the articles within this Special Issue describes the latest findings on this issue through the use of atomic force microscopy .2 groups within its matrix is described [Agriculture is another field where the use of nanoMOFs is of great interest. In the third article, the inclusion of the fungicide diniconazole into a MIL-101(Fe) nanoMOF containing free NHescribed . FurtherThe aim of this Special Issue is to offer the readers a compilation of cutting-edge research within the porous metal–organic framework nanoparticles field, providing insights into its current challenges and future directions and further increasing interest of this topic. We hope that all readers will enjoy it.