Neuroprotective Approaches for Brain Injury After Cardiac Arrest: Current Trends and Prospective Avenues.

With the implementation of improved bystander cardiopulmonary resuscitation techniques and public-access defibrillation, survival after out-of-hospital cardiac arrest (OHCA) has increased significantly over the years. Nevertheless, OHCA survivors have residual anoxia/reperfusion brain damage and associated neurological impairment resulting in poor quality of life. Extracorporeal membrane oxygenation or targeted temperature management has proven effective in improving post-cardiac arrest (CA) neurological outcomes, yet considering the substantial healthcare costs and resources involved, there is an urgent need for alternative treatment strategies that are crucial to alleviate brain injury and promote recovery of neurological function after CA. In this review, we searched PubMed for the latest preclinical or clinical studies (2016-2023) utilizing gas-mediated, pharmacological, or stem cell-based neuroprotective approaches after CA. Preclinical studies utilizing various gases (nitric oxide, hydrogen, hydrogen sulfide, carbon monoxide, argon, and xenon), pharmacological agents targeting specific CA-related pathophysiology, and stem cells have shown promising results in rodent and porcine models of CA. Although inhaled gases and several pharmacological agents have entered clinical trials, most have failed to demonstrate therapeutic effects in CA patients. To date, stem cell therapies have not been reported in clinical trials for CA. A relatively small number of preclinical stem-cell studies with subtle therapeutic benefits and unelucidated mechanistic explanations warrant the need for further preclinical studies including the improvement of their therapeutic potential. The current state of the field is discussed and the exciting potential of stem-cell therapy to abate neurological dysfunction following CA is highlighted.

Real experience of caregivers of patients with HIV/AIDS from the perspective of iceberg theory: a qualitative research.

OBJECTIVE: This study aimed to investigate the caregiving behaviours and supportive needs of caregivers of patients with HIV/AIDS and provide a basis for healthcare institutions to carry out caregiver interventions. DESIGN: A purposive sampling method was used to select 11 caregivers of patients with HIV/AIDS in the Infectious Disease Department of a tertiary hospital in Nanjing, China, to conduct semistructured interviews. Colaizzi analysis was used to collate and analyse the interview data. SETTING: All interviews were conducted at a tertiary hospital specialising in infectious diseases in Nanjing, Jiangsu Province. PARTICIPANTS: We purposively sampled 11 caregivers of people with HIV/AIDS, including nine women and two men. RESULTS: Analysing the results from the perspective of iceberg theory, three thematic layers were identified: behavioural, value and belief. The behavioural layer includes a lack of awareness of the disease, physical and mental coping disorders, and an increased sense of stigma; the values layer includes a heightened sense of responsibility, the constraints of traditional gender norms, the influence of strong family values and the oppression of public opinion and morality and the belief layer includes the faith of standing together through storms and stress. CONCLUSION: Healthcare professionals should value the experiences of caregivers of patients with HIV/AIDS and provide professional support to improve their quality of life.

The role of tumor parenchyma and brain cortex signal intensity ratio in differentiating solitary fibrous tumors and meningiomas.

BACKGROUND: Solitary fibrous tumors (SFT) and meningiomas (MA) have similar clinical and radiographic presentations but require different treatment approaches and have different prognoses. This emphasizes the importance of a correct preoperative diagnosis of SFT versus MA. OBJECTIVE: In this study, investigated the differences in imaging characteristics between SFT and MA to improve the accuracy of preoperative imaging diagnosis of SFT. METHODS: The clinical and imaging data of 26 patients with SFT and 104 patients with MA who were pathologically diagnosed between August 2017 and December 2022, were retrospectively analyzed. The clinical and imaging differences between SFT and MA, as well as between the various pathological grades of SFT, were analyzed. RESULTS: Age, gender, cystic change, flow void phenomenon, yin-yang sign, lobulation, narrow base, tumor/cortex signal ratio (TCSR) > 1.0 in T1-weighted imaging (T1WI), TCSR ≥ 1.1 in T2-weighted imaging (T2WI), peritumoral edema, and absence of dural tail sign varied between SFT and MA. As per the receiver operating characteristic (ROC) curve analysis, TCSR > 1 in T1WI has the maximum diagnostic accuracy for SFT. Cranial or venous sinus invasion had a positive effect on SFT (Grade III, World Health Organization (WHO) grading). CONCLUSION: Among the many radiological and clinical distinctions between SFT and MA, TCSR ≥ 1 exhibits the highest predictive efficacy for SFT; while cranial or venous sinus invasion may be a predictor of WHO grade III SFT.

Experiment and Simulation Study of the Laser-Induced Cavitation Bubble Technique for Forming a Microgroove in Aluminum Foil.

The present work introduces a laser-induced cavitation bubble technique for forming an axisymmetric structure (i.e., microgroove) and the dynamics of a cavitation bubble from initial expansion to the collapse stages that were also simulated. Furthermore, the shock wave signals and dynamic properties of the cavitation bubble were recorded using a hydrophone and a high-speed camera. The experiments on microgrooves formed by laser-induced cavitation bubble stamping were carried out, and the effects of laser energy, the initial position of the bubble, and the number of impacts on the microformability of aluminum sheets are discussed. The depth of the microgroove was investigated using experiments, and it was found that the process can serve as a rapid technique for impressing microfeatures on thin-sheet metals. The experimental results showed that as the initial position of the bubble increased, the deformation depth decreased. As the laser energy and number of impacts increased, the deformation depth increased. The results of the response surface experiments showed that a laser energy of 27 mJ, 3 impacts, and a bubble position of 3 mm were optimal for the process. By using the optimal parameters, flat and smooth microgrooves with a forming depth of 102.54 µm were successfully fabricated. Furthermore, the maximum thickness thinning of the microgroove section occurred at the entrance areas, and this area had the greatest hardness. This also indicated that the greatest amount of plastic deformation of the material and grain refinement occurred in this area. On the other hand, the aluminum foil did not undergo oxidation during the plastic deformation process. These results demonstrated that laser-induced bubble stamping is an advanced micromachining method with promising applications.

Longitudinal-Torsional Ultrasonic Grinding of GCr15: Development of Longitudinal-Torsional Ultrasonic System and Prediction of Surface Topography.

The common material of bearing rings is GCr15 bearing steel which is a typical difficult-to-machine material. As an important working surface of the bearing, the inner surface of the raceway plays a vital role in the performance of the bearing. As an important means to solve the high-performance manufacturing of difficult-to-machine materials, longitudinal-torsional ultrasonic processing is widely used in various types of processing. In the presented work, the basic size of the horn is obtained from the wave equation of the forced vibration, and the modal analysis and amplitude test are carried out to verify the rationality of the LUTG structure. Then, according to the probability density function of cutting thickness and the overlapping effect of adjacent abrasive trajectories, the LUTG surface topography prediction model is established by using the height formula of the surface residual material, and the model reliability is verified by using the orthogonal test. The error between the test results and the prediction model is within 13.2%. Finally, based on the response surface method, the optimal process parameters that can meet the requirements of low roughness (Ra) and high material removal rate (MRR) are screened, and the optimal combination of process parameters is obtained as follows: A = 4.5 µm, n = 6493.3 r/min, ap = 28.4 µm, and vf = 21.1 mm/min.

Neuroprotection of Stem Cells Against Ischemic Brain Injury: From Bench to Clinic.

Neurological injuries can have numerous debilitating effects on functional status including sensorimotor deficits, cognitive impairment, and behavioral symptoms. Despite the disease burden, treatment options remain limited. Current pharmacological interventions are targeted at symptom management but are ineffective in reversing ischemic brain damage. Stem cell therapy for ischemic brain injury has shown promising preclinical and clinical results and has attracted attention as a potential therapeutic option. Various stem cell sources (embryonic, mesenchymal/bone marrow, and neural stem cells) have been investigated. This review provides an overview of the advances made in our understanding of the various types of stem cells and progress made in the use of these stem cells for the treatment of ischemic brain injuries. In particular, the use of stem cell therapy in global cerebral ischemia following cardiac arrest and in focal cerebral ischemia after ischemic stroke are discussed. The proposed mechanisms of stem cells' neuroprotective effects in animal models (rat/mice, pig/swine) and other clinical studies, different routes of administration (intravenous/intra-arterial/intracerebroventricular/intranasal/intraperitoneal/intracranial) and stem cell preconditioning are discussed. Much of the promising data on stem cell therapies after ischemic brain injury remains in the experimental stage and several limitations remain unsettled. Future investigation is needed to further assess the safety and efficacy and to overcome the remaining obstacles.

The role of perceived expertise and trustworthiness in research study and clinical trial recruitment: Perspectives of clinical research coordinators and African American and Black Caribbean patients.

This study investigates the role of source credibility on minority participant recruitment, particularly African American and Black Caribbean patients. A total of nine focus groups (N = 48 participants) were conducted with both patient groups and clinical research coordinators (CRCs). Using the elaboration likelihood model as a guiding framework for analysis, this study found that the credibility of research coordinators (or other professionals who recruit for research studies and clinical trials) was instrumental in shaping attitudes of prospective participants. The perspectives of patients and CRCs aligned closely, with few exceptions. For both groups, professionalism and professional displays (clothing, institutional artifacts) enhanced perceived expertise, a core component of credibility. Trustworthiness, another important component of credibility, was fostered through homophily between recruiter and patient, expressions of goodwill and assuaging anxiety about CRCs' financial motivations for recruitment. Additionally, CRCs believed that credibility was supported when CRCs could emphasize transparency and truthfulness in communication. The importance of these findings for the development of empirically-based training programs to improve communication practices in recruitment contexts is discussed.

Differentiation state and culture conditions impact neural stem/progenitor cell-derived extracellular vesicle bioactivity.

Extracellular vesicles (EVs) derived from neural progenitor/stem cells (NPSCs) have shown promising efficacy in a variety of preclinical models. However, NPSCs lack critical neuroregenerative functionality such as myelinating capacity. Further, culture conditions used in NPSC EV production lack standardization, limiting reproducibility challenging and potentially potency of the overall approach via lack of optimization. Here, we assessed whether oligodendrocyte precursor cells (OPCs) and immature oligodendrocytes (iOLs), which are further differentiated than NPSCs and which both give rise to mature myelinating oligodendrocytes, could yield EVs with neurotherapeutic properties comparable or superior to those from NPSCs. We additionally examined the effects of extracellular matrix (ECM) coating materials and the presence or absence of growth factors in cell culture on the ultimate properties of EVs. The data show that OPC EVs and iOL EVs performed similarly to NPSC EVs in cell proliferation and anti-inflammatory assays, but NPSC EVs performed better in a neurite outgrowth assay. Additionally, the presence of nerve growth factor (NGF) in culture was found to maximize NPSC EV bioactivity among the conditions tested. NPSC EVs produced under rationally-selected culture conditions (fibronectin + NGF) enhanced axonal regeneration and muscle reinnervation in a rat nerve crush injury model. These results highlight the need for standardization of culture conditions for neurotherapeutic NPSC EV production.

Improving Schwann Cell Differentiation from Human Adipose Stem Cells with Metabolic Glycoengineering.

Schwann cells (SCs) are myelinating cells that promote peripheral nerve regeneration. When nerve lesions form, SCs are destroyed, ultimately hindering nerve repair. The difficulty in treating nerve repair is exacerbated due to SC's limited and slow expansion capacity. Therapeutic use of adipose-derived stem cells (ASCs) is emerging in combating peripheral nerve injury due to these cells' SC differentiation capability and can be harvested easily in large numbers. Despite ASC's therapeutic potential, their transdifferentiation period typically takes more than two weeks. In this study, we demonstrate that metabolic glycoengineering (MGE) technology enhances ASC differentiation into SCs. Specifically, the sugar analog Ac5ManNTProp (TProp), which modulates cell surface sialylation, significantly improved ASC differentiation with upregulated SC protein S100ß and p75NGFR expression and elevated the neurotrophic factors nerve growth factor beta (NGFß) and glial cell-line-derived neurotrophic factor (GDNF). TProp treatment remarkably reduced the SC transdifferentiation period from about two weeks to two days in vitro, which has the potential to improve neuronal regeneration and facilitate future use of ASCs in regenerative medicine.

Reducing Health Disparities Among African American and Black Caribbean Patients by Improving the Communication Practices of Clinical Research Coordinators.

This manuscript focuses on the communication factors that affect the willingness of African Americans and Black Caribbean patients to participate in clinical trials and research studies. Low rates of research participation by members of communities of color have long been linked to health disparities. While there are many factors that contribute to low rates of accrual of African American and Black patients to clinical trials, a lack of attention to communication factors that enhance or inhibit the recruitment process is central to the problem. In this study, we describe results from the analysis of six focus groups (N = 31) consisting of African American (k = 3) and Black Caribbean (k = 3) participants. Our analyses focus on verbal and nonverbal communication behaviors and how they affect participants' willingness to participate in clinical trials. Specifically, when clinical research coordinators (CRCs) had a professional appearance, made the effort to explain a study in detail, made eye contact, took the time to listen and answer questions patiently, and gave the sense that the CRC was being truthful and transparent, patients felt respected and valued. Additionally, participants emphasized the importance of the process of developing and maintaining a trusting relationship between study participants and CRCs. The results of this study will be used to develop a clinical trial communication training program designed to enhance the communication skills of clinical research coordinators who discuss research participation with African American and Caribbean Black patients.

COVID-19 Information Overload Mediated the Effects of Cross-Channel Information Differences on Health Information Elaboration.

The COVID-19 pandemic has brought on an unprecedented amount of information about the virus and vaccination, varying significantly across information channels. While extant research shows that excessive information leads to overload and less elaboration, few studies have examined factors associated with information overload and elaboration. Considering the trend that we likely receive information on the same topics from different communication channels daily, this study sought to understand how cross-channel differences in the information were associated with information overload and subsequent elaboration. The survey assessed 471 participants' consumption of COVID-19 information across different channels (interpersonal communication vs. social media), concern about information quality, information overload, information elaboration, health literacy, and demographic characteristics in February 2021. Our findings confirmed that greater information overload was negatively associated with more information elaboration. Using a moderated mediation model, we found that people who received more information from social media, compared to those who received equal amounts of information from both social media and interpersonal communications, reported more information overload and less elaboration. Additionally, we found that people who experienced greater information overload and held greater concern about information quality tended to elaborate more information. All analyses were controlled for health literacy. Theoretical and practical implications were discussed.

Stem Cell Therapy for Ischemic Brain Injury: Early Intranasal Delivery after Cardiac Arrest.

Global ischemic brain injury is the leading cause of mortality and long-term disability in patients resuscitated from cardiac arrest. Hypothermia and neuroprotective agents are two strategies partially improve neurological outcomes following resuscitation. However, the therapeutic effects of these treatments are inconsistently reported. Stem cell therapy has emerged as a promising protective strategy due to its potential for proliferation and differentiation into functional neural cells. This editorial reviews the current status of stem cell therapy via the intranasal route in primates and clinical studies, along with the treatment window of stem cell therapy in ischemic brain injury after cardiac arrest to provide new insight into stem cell therapy for cardiac arrest-induced global cerebral ischemia injury.

NIR-excited upconversion nanoparticles used for targeted inhibition of Aß42 monomers and disassembly of Aß42 fibrils.

Much attention has been paid to oxidising amyloid-ß peptides (Aß) for inhibiting their aggregation using photosensitive materials. However, the low penetration of ultraviolet/visible light into biological tissues and low targeting properties of the materials hinder their application. Here, we constructed a novel platform for attenuating the neurotoxicity of Aß through functional upconversion nanoparticles (UCNPs@SiO2-ThS). UCNPs@SiO2-ThS can not only inhibit the aggregation of Aß42 monomers, but also disassemble Aß42 fibrils by its selective photooxidative capacity under the irradiation of near-infrared (NIR) light. Moreover, based on the enhancement of ThS fluorescence after attaching to Aß42 fibrils, only Aß42 fibrils exposed to both UCNPs@SiO2-ThS and light can be oxidized rather than other normal proteins. To further enhance Aß-target photooxygenation, we introduced the Aß-target peptide (KLVFF) on the surface. Compared to traditional chemotherapies and radiotherapies, this novel PDT strategy shows remarkably reduced side effects and improved targeting.

Measuring information overload and message fatigue toward COVID-19 prevention messages in USA and China.

COVID-19 prevention messages are a crucial component of disease mitigation strategies and the primary driver of health decision-making during the global pandemic. However, the constant and repetitive nature of COVID-19 messaging may cause unintended consequences. Among the commonly observed phenomena are information overload and message fatigue, which might be experienced differently depending on cultural background. Using measurement invariance testing, this study compared how individuals from two countries-USA (n = 493) and China (n = 571)-experienced information overload and message fatigue toward COVID-19 prevention messages. Findings revealed that people in China showed significantly lower level of information overload and message fatigue than those in the USA. This study explores the extent of the unintended persuasive effects that people have experienced during the COVID-19 pandemic in different societies, a comparison which has never been studied before, even outside of the context of COVID-19. The study also provides much-needed practical insights to develop public health initiatives that improve COVID-19 prevention communication, which can further reduce these unintended effects in both countries, and has implications for other countries as well.

Neuroprotection of NSC Therapy is Superior to Glibenclamide in Cardiac Arrest-Induced Brain Injury via Neuroinflammation Regulation.

Cardiac arrest (CA) is common and devastating, and neuroprotective therapies for brain injury after CA remain limited. Neuroinflammation has been a target for two promising but underdeveloped post-CA therapies: neural stem cell (NSC) engrafting and glibenclamide (GBC). It is critical to understand whether one therapy has superior efficacy over the other and to further understand their immunomodulatory mechanisms. In this study, we aimed to evaluate and compare the therapeutic effects of NSC and GBC therapies post-CA. In in vitro studies, BV2 cells underwent oxygen-glucose deprivation (OGD) for three hours and were then treated with GBC or co-cultured with human NSCs (hNSCs). Microglial polarization phenotype and TLR4/NLRP3 inflammatory pathway proteins were detected by immunofluorescence staining. Twenty-four Wistar rats were randomly assigned to three groups (control, GBC, and hNSCs, N = 8/group). After 8 min of asphyxial CA, GBC was injected intraperitoneally or hNSCs were administered intranasally in the treatment groups. Neurological-deficit scores (NDSs) were assessed at 24, 48, and 72 h after return of spontaneous circulation (ROSC). Immunofluorescence was used to track hNSCs and quantitatively evaluate microglial activation subtype and polarization. The expression of TLR4/NLRP3 pathway-related proteins was quantified via Western blot. The in vitro studies showed the highest proportion of activated BV2 cells with an increased expression of TLR4/NLRP3 signaling proteins were found in the OGD group compared to OGD + GBC and OGD + hNSCs groups. NDS showed significant improvement after CA in hNSC and GBC groups compared to controls, and hNSC treatment was superior to GBC treatment. The hNSC group had more inactive morphology and anti-inflammatory phenotype of microglia. The quantified expression of TLR4/NLRP3 pathway-related proteins was significantly suppressed by both treatments, and the suppression was more significant in the hNSC group compared to the GBC group. hNSC and GBC therapy regulate microglial activation and the neuroinflammatory response in the brain after CA through TLR4/NLRP3 signaling and exert multiple neuroprotective effects, including improved neurological function and shortened time of severe neurological deficit. In addition, hNSCs displayed superior inflammatory regulation over GBC.

Effect of Graded Targeted Temperature Management on Cerebral Glucose Spatiotemporal Characteristics after Cardiac Arrest.

Cardiac arrest (CA) is a fatal disease with high rates of neurological impairment. At present, targeted temperature management (TTM) is the only strategy with firm clinical evidence to prove its effectiveness. However, there is still controversy on the implementation of TTM, particularly on its depth, with a lack of elucidated underlying therapeutic mechanisms. Six Wistar rats were subjected to 8 min asphyxia-CA and randomly divided into TTM at 33oC(n=3) or 35° C groups (n=3). The spatiotemporal characteristics of cerebral glucose metabolism after CA were investigated by 18F-FDG microPET/CT. Myelin Basic Protein (MBP) immunofluorescence staining was used to assess acute injury and recovery of oligodendrocytes. Functional recovery was evaluated using the neurological deficit score (NDS). There was a significant improvement in functional recovery by NDS (p < 0.05) in the 33oC group compared with the 35° C group. Glucose metabolism of the 33° C group was higher than that of the 35oC group early after resuscitation (within 10 minutes). Immunofluorescence analysis showed that positive MBP signals in the cortex and hippocampus in the 33oC group were greater than in the 35oC group. In conclusion, compared to 35oC TTM, 33° C TTM changed the spatiotemporal characteristics of brain glucose metabolisms with improved neurological function, which may be through oligodendrocyte participation.