Ferroptosis mechanism and Alzheimer's disease

Regulated cell death is a genetically determined form of programmed cell death that commonly occurs during the development of living organisms. This process plays a crucial role in modulating homeostasis and is evolutionarily conserved across a diverse range of living organisms. Ferroptosis is a classic regulatory mode of cell death. Extensive studies of regulatory cell death in Alzheimer's disease have yielded increasing evidence that ferroptosis is closely related to the occurrence, development, and prognosis of Alzheimer's disease. This review summarizes the molecular mechanisms of ferroptosis and recent research advances in the role of ferroptosis in Alzheimer's disease. Our findings are expected to serve as a theoretical and experimental foundation for clinical research and targeted therapy for Alzheimer's disease.

[Clinical and electrophysiological characteristics and treatment outcomes of anti-neutrophil cytoplasmic antibody ANCA-associated vasculitic neuropathy]

Objective: To investigate the clinical and electrophysiological characteristics of ANCA-associated vasculitic neuropathy (VN) and analyze the predictors of treatment outcomes. Methods: Retrospective case series. In all, 652 consecutive patients with ANCA-associated vasculitis were admitted to the First Medical Center of the Chinese PLA General Hospital between January 2006 and December 2022. Peripheral neuropathy occurred in 91 patients. Patients were excluded if other known causes of neuropathy were present. Sixty-one patients were eventually enrolled, including 17 with eosinophilic granulomatosis with polyangiitis (EGPA), 11 with granulomatosis polyangiitis (GPA), and 33 with microscopic polyangiitis (MPA). Their clinical data were collected and clinical characteristics, VN manifestations, electrophysiological findings (including interside amplitude ratio [IAR]), and treatment outcomes were compared among the three subsets of AAV. Then, factors influencing the treatment outcomes were analyzed using multivariable logistic regression analysis. Results: Peripheral neuropathy occurred in 62.1%(18/29) of EGPA, 8.3%(15/180) of GPA, and 13.1%(58/443) of MPA patients. The age at onset and examination was higher in patients with MPA than those with EGPA or GPA (P<0.01). The occurrence of VN was later in patients with GPA than those with EGPA (P<0.01), and the GPA group had fewer affected nerves than the other two groups (P<0.016). The abnormal IARs of motor nerves in lower limbs were more detected in the EGPA than the MPA group (P<0.01). Logistic regression analysis suggested that higher Birmingham vasculitis activity score-version 3 (BVAS-V3) (OR=6.85, 95%CI 1.33-35.30) was associated with better treatment outcomes of VN. However, central nervous system involvement was a risk factor for poor treatment outcomes (OR=0.13, 95%CI 0.02-0.89). Conclusions: The clinical and electrophysiological characteristics of VN were slightly different among subsets of AAV. Patients with GPA often presented with polyneuropathy and had fewer nerves affected; mononeuritis multiplex was more common in EGPA than GPA and MPA. Higher BVAS-V3 and central nervous system involvement might predict the treatment outcome of VN.

Targeted long-read sequencing for comprehensive detection of CYP21A2 mutations in patients with 21-hydroxylase deficiency

BACKGROUND

21-Hydroxylase deficiency (21-OHD) is caused by pathogenic CYP21A2 variations. CYP21A2 is arranged in tandem with its highly homologous pseudogene CYP21A1P; therefore, it is prone to mismatch and rearrangement, producing different types of complex variations. There were few reports on using only one method to detect different CYP21A2 variants simultaneously.

AIMS

Targeted long-read sequencing method was used to detect all types of CYP21A2 variants in a series of patients with 21-OHD.

METHODS

A total of 59 patients with 21-OHD were enrolled from Peking Union Medical College Hospital. Long-range locus-specific PCR and long-read sequencing (LRS) were performed to detect the pathogenic variants in CYP21A2.

RESULTS

Copy-number variants of CYP21A2 were found in 25.4% of patients, including 5.1% with 3 copies of CYP21A2, 16.9% with 1 copy of CYP21A2, and 3.4% with 0 copy of CYP21A2. The remaining 74.6% of patients had 2 copies of CYP21A2. Pathogenic variants were identified in all 121 alleles of 59 patients. Specifically, single-nucleotide variants and small insertions/deletions (< 50 bp) were detected in 79 alleles, of which conversed from CYP21A1P were detected in 63 alleles, and rare variants were found in the other 16 alleles. Large gene conversions (> 50 bp) from pseudogene were detected in 10 alleles, and different chimeric genes (CYP21A1P/CYP21A2 or TNXA/TNXB) formed by large deletions were detected in 32 alleles. Of all variants, p.I173N was the most common variant (19.0%).

CONCLUSIONS

Our study demonstrated that targeted long-read sequencing is a comprehensive method for detecting CYP21A2 variations, which is helpful for genetic diagnosis in 21-OHD patients.

Oxidized SOD1 accelerates cellular senescence in neural stem cells

BACKGROUND

Neural stem cells (NSCs), especially human NSCs, undergo cellular senescence characterized by an irreversible proliferation arrest and loss of stemness after prolonged culture. While compelling correlative data have been generated to support the oxidative stress theory as one of the primary determinants of cellular senescence of NSCs, a direct cause-and-effect relationship between the accumulation of oxidation-mediated damage and cellular senescence of NSCs has yet to be firmly established. Human SOD1 (hSOD1) is susceptible to oxidation. Once oxidized, it undergoes aberrant misfolding and gains toxic properties associated with age-related neurodegenerative disorders. The present study aims to examine the role of oxidized hSOD1 in the senescence of NSCs.

METHODS

NSCs prepared from transgenic mice expressing the wild-type hSOD1 gene were maintained in culture through repeated passages. Extracellular vesicles (EVs) were isolated from culture media at each passage. To selectively knock down oxidized SOD1 in NSCs and EVs, we used a peptide-directed chaperone-mediated protein degradation system named CT4 that we developed recently.

RESULTS

In NSCs expressing the hSOD1 from passage 5, we detected a significant increase of oxidized hSOD1 and an increased expression of biomarkers of cellular senescence, including upregulation of P53 and SA-β-Gal and cytoplasmic translocation of HMGB1. The removal of oxidized SOD1 remarkably increased the proliferation and stemness of the NSCs. Meanwhile, EVs derived from senescent NSCs carrying the wild-type hSOD1 contained high levels of oxidized hSOD1, which could accelerate the senescence of young NSCs and induce the death of cultured neurons. The removal of oxidized hSOD1 from the EVs abolished their senescence-inducing activity. Blocking oxidized SOD1 on EVs with the SOD1 binding domain of the CT4 peptide mitigated its toxicity to neurons.

CONCLUSION

Oxidized hSOD1 is a causal factor in the cellular senescence of NSCs. The removal of oxidized hSOD1 is a strategy to rejuvenate NSCs and to improve the quality of EVs derived from senescent cells.

Novel SERS Signal Amplification Strategy for Ultrasensitive and Specific Detection of Spinal Cord Injury-Related miRNA

The expression of microRNA (miRNA) changes in many diseases plays an important role in the diagnosis, treatment, and prognosis of diseases. Spinal cord injury (SCI) is a serious disease of the central nervous system, accompanied by inflammation, cell apoptosis, neuronal necrosis, axonal rupture, demyelination, and other pathological processes, resulting in impaired sensory and motor functions of patients. Studies have shown that miRNA expression has changed after SCI, and miRNAs participate in the pathophysiological process and treatment of SCI. Therefore, quantitative analysis and monitoring of the expression of miRNA were of great significance for the diagnosis and treatment of SCI. Through the SCI-related miRNA chord plot, we screened out miRNA-21-5p and miRNA-let-7a with a higher correlation. However, for traditional detection strategies, it is still a great challenge to achieve a fast, accurate, and sensitive detection of miRNA in complex biological environments. The most frequently used method for detecting miRNAs is polymerase chain reaction (PCR), but it has disadvantages such as being time-consuming and cumbersome. In this paper, a novel SERS sensor for the quantitative detection of miRNA-21-5p and miRNA-let-7a in serum and cerebrospinal fluid (CSF) was developed. The SERS probe eventually formed a sandwich-like structure of Fe3O4@hpDNA@miRNA@hpDNA@GNCs with target miRNAs, which had high specificity and stability. This SERS sensor achieved a wide range of detection from 1 fM to 1 nM and had a good linear relationship. The limits of detection (LOD) for miRNA-21-5p and miRNA-let-7a were 0.015 and 0.011 fM, respectively. This new strategy realized quantitative detection and long-term monitoring of miRNA-21-5p and miRNA-let-7a in vivo. It is expected to become a powerful biomolecule analysis tool and will provide ideas for the diagnosis and treatment of many diseases.

Interleukin-4 Modulates Neuroinflammation by Inducing Phenotypic Transformation of Microglia Following Subarachnoid Hemorrhage

Neuroinflammation, a key pathological feature following subarachnoid hemorrhage (SAH), can be therapeutically targeted by inhibiting microglia M1 polarization and promoting phenotypic transformation to M2 microglia. Interleukin-4 (IL-4) is a pleiotropic cytokine known to its regulation of physiological functions of the central nervous system (CNS) and mediate neuroinflammatory processes. However, its specific role in neuroinflammation and microglia responses following SAH remains unexplored. In this investigation, we established both in vivo and in vitro SAH models and employed a comprehensive array of assessments, including ELISA, neurofunctional profiling, immunofluorescence staining, qRT-PCR, determination of phagocytic capacity, and RNA-Seq analyses. The findings demonstrate an elevated expression of IL-4 within cerebrospinal fluid (CSF) subsequent to SAH. Furthermore, exogenous administration of IL-4 ameliorates post-SAH neurofunctional deficits, attenuates cellular apoptosis, fosters M2 microglia phenotype conversion, and mitigates neuroinflammatory responses. The RNA-Seq analysis signifies that IL-4 governs the modulation of neuroinflammation in microglia within an in vitro SAH model through intricate cascades of signaling pathways, encompassing interactions between cytokines and cytokine receptors. These discoveries not only augment comprehension of the neuropathogenesis associated with post-SAH neuroinflammation but also present novel therapeutic targets for the management thereof.

Risk factors for portal vein system thrombosis after partial splenic embolisation in cirrhotic patients with hypersplenism

AIM

To determine risk factors for portal venous system thrombosis (PVST) after partial splenic artery embolisation (PSAE) in cirrhotic patients with hypersplenism.

MATERIALS AND METHODS

Between March 2014 and February 2022, 428 cirrhotic patients with hypersplenism underwent partial splenic artery embolisation and from these patients 208 were enrolled and 220 were excluded. Medical records of enrolled patients were collected. Computed tomography (CT) images were reviewed by two blinded, independent radiologists. Statistical analyses were performed by using SPSS.

RESULTS

Progressive PVST was observed in 18.75% (39/208) of cirrhotic patients after PSAE. No significant differences in peripheral blood counts, liver function biomarkers, and renal function were observed between the patients with progressive PVST and the patients without progressive PVST. The imaging data showed significant differences in PVST, the diameters of the portal, splenic, and superior mesenteric veins between the progressive PVST group and non-progressive PVST group. Univariate and multivariate analysis demonstrated portal vein thrombosis, spleen infarction percentage, and the diameter of the splenic vein were independent risk factors for progressive PVST. Seventeen of 173 (9.83%) patients showed new PVST; the growth of PVST was observed in 62.86% (22/35) of the patients with pre-existing PVST. Spleen infarction percentage and the diameter of the splenic vein were independent risk factors for new PVST after PSAE.

CONCLUSION

The present study demonstrated portal vein thrombosis, spleen infarction percentage, and the diameter of the splenic vein were independent risk factors for PVST after PSAE in cirrhotic patients with hypersplenism.

Gene therapy of adeno-associated virus (AAV) vectors in preclinical models of ischemic stroke

Stroke has been associated with devastating clinical outcomes, with current treatment strategies proving largely ineffective. Therefore, there is a need to explore alternative treatment options for addressing post-stroke functional deficits. Gene therapy utilizing adeno-associated viruses (AAVs) as a critical gene vector delivering genes to the central nervous system (CNS) gene delivery has emerged as a promising approach for treating various CNS diseases. This review aims to provide an overview of the biological characteristics of AAV vectors and the therapeutic advancements observed in preclinical models of ischemic stroke. The study further investigates the potential of manipulating AAV vectors in preclinical applications, emphasizing the challenges and prospects in the selection of viral vectors, drug delivery strategies, immune reactions, and clinical translation.

A Microfluidics-Based Multiplex SERS Immunoassay Device for Analysis of Acute Ischemic Stroke Biomarkers

Sensitive and accurate methods for early detection of acute ischemic stroke (AIS) are essential for timely treatment and prognostic assessment of patients. In this study, we report a microfluidics-based ultrasensitive surface-enhanced Raman scattering (SERS) immunoassay device for the quantitative determination of multiplex biomarkers in AIS. By preparing 5,5'-dithiobis-2-nitrobenzoic acid (DTNB) antibody-modified gold nanoparticles (AuNPs) on SERS devices as SERS probes, the biomarkers in whole blood of AIS were accurately captured and further visualized for SERS signal intensity quantitative analysis of six biomarkers in the blood samples. It is worth mentioning that the limit of detection (LOD) of the method can reach the level of fg/mL, with excellent sensitivity and selectivity. Meanwhile, the analytical comparison with ELISA method showed that the detection results of both methods were consistent, which verified the feasibility of the assembled device. The SERS immunoassay device detection provides a powerful strategy for the prediction, early diagnosis and dynamic monitoring of prognosis of AIS with a wide range of clinical practice prospects.

Bridging the Gap of Radiotherapy Treatment Planning Quality between High-Income, and Low- and Middle-Income Countries Using Knowledge-Based Planning

PURPOSE/OBJECTIVE(S)

Radiotherapy departments in low- and middle-income countries (LMICs) like Guatemala have recently introduced intensity-modulated radiotherapy (IMRT). IMRT has become the standard of care in high-income countries (HIC) due to reduced toxicity and improved outcomes in some cancers. The purpose of this work is to show the feasibility of adapting knowledge-based (KB) models established in a HIC to a LMIC lacking experience in IMRT to improve plan quality and planning efficiency.

MATERIALS/METHODS

A Halcyon Linac was installed at our clinic in Guatemala in 2019 and has been used to treat approximately 90 patients daily with IMRT. A model developed on a cohort of head and neck cancer patients at a US academic radiotherapy center were applied at our center to create 20head and neck VMAT plans with different prescriptions, including simultaneous-integrated and sequential boosts.

RESULTS

The plans created using the KB models achieved similar coverage of the planning target volume for each plan KB plans showed better 1) Parotid sparing with a mean dose reduction between 5%-25% and spinal cord maximum dose reduction between 3%-15%. The time efficiency to create VMAT plans using KB model versus manual planning improved four-fold, on average one hour versus more than 4 hours, respectively.

CONCLUSION

Despite different prescriptions, guidelines and demographics of cancer patients between two institutions in a HIC and LMIC, this work demonstrates that KB planning can be used to generate better and more consistent VMAT plans versus manually created plans. In addition, KB planning has the potential to greatly increase planning efficiency higher efficiency and help address the shortage of medical physicists and dosimetrists in LMICs.

Dissecting Systemic T Cell Responses after Stereotactic Ablative Radiotherapy in NSCLC by Single-Cell RNA and T Cell Receptor Sequencing

PURPOSE/OBJECTIVE(S)

There is accumulating evidence that stereotactic ablative radiotherapy (SABR) modulates immune responses to cancer; combining SABR and immunotherapy could promote the abscopal effect, but the precise effects of SABR on patients' systemic T cells is unclear. Here, we investigated SABR-induced systemic T cell response in early-stage non-small cell lung cancer (NSCLC) by single-cell RNA and T cell receptor sequencing.

MATERIALS/METHODS

We performed single-cell RNA and T cell receptor sequencing on 29,439 T cells from four pairs of peripheral blood before and after SABR in early-stage NSCLC patients. Cell clustering and dimensionality reduction, SingleR, feature genes score, and TCR profiling analyses were used to investigate the heterogeneity of T cells and their changes following SABR.

RESULTS

We identified fourteen T cell subtypes using unsupervised graph-based clustering of uniform manifold approximation and projection. By comparing the gene set scores of CD8_TE and CD8_EM pre- and post-SABR, we found both cytotoxic and inhibitory scores were significantly elevated in CD8_TE (both P < 0.001), while cytotoxic score was significantly increased in CD8_EM (P < 0.001) after SABR. We also found that CD4_TE showed increased cytotoxic scores and decreased Treg scores (P < 0.001 and < 0.05, respectively), while Treg cells showed decreased inhibitory and Treg scores (P < 0.001 and <0.01, respectively) after SABR. The proportion of large TCR clones was higher after SABR, which was accompanied by a decrease in proportion of single clones. When we compared the transcriptomes of CD8_TE cells between the single, small and large clones post-SABR, we found high expression of GZMB and KLRC3 in cells with large clones, and GZMK, IL7R, and SELL in small and single clones. This suggested that T cells after SABR with large clones may have higher cytotoxicity than those with small and single clones.

CONCLUSION

Our study identified systemic T cell activation after SABR at single-cell resolution, providing unprecedented insight into the immune-modulatory role of SABR in early-stage NSCLC.

Standardizing LT Chest Wall Radiotherapy Treatment Planning in a Low- or Middle- Income Country Radiotherapy Clinic Using Knowledge Based Planning

PURPOSE/OBJECTIVE(S)

Radiotherapy departments in low- or middle-income countries (LMICs) tend to lag behind introducing emerging technologies like intensity-modulated radiotherapy (IMRT). IMRT has become the standard of care in high-income countries (HIC) due to reduced toxicity and improved outcomes in a wide variety of cancers. The purpose of this work is showing the results of left Chest-Wall knowledge-based planning (KBP) standardization and implementation in a LMIC setting.

MATERIALS/METHODS

A Halcyon Linac was installed at our clinic in Guatemala in 2019 and currently used to treat ∼90 IMRT patients daily. The standardization of IMRT procedures has been difficult for complex sites like chest-wall. The steps for standardization included: AAPM TG-263 nomenclature implementation, and planning workflows within the TPS, creation of optimization structures, and plan quality evaluation following RTOG1005 protocol hypofractionation arm. 25 plans were created manually achieving all RTOG1005 protocol constraints. The statistics were analyzed trough the model analytics tool provided by KPB manufacturer.

RESULTS

The results show that more plans are needed to improve the KBP model. This initial model was used to create a standardized clinical protocol in the TPS in order to continue adding plans to the KBP model database. This approach ensures that we obtain consistent plan quality and standardize our planning. The manual planning objectives achieved: CONCLUSION: The experience using the TPS to standardize our treatment planning process achieved good consistency in our planning objectives. This approach will help create KBP models according to our own clinic-specific requirements. Future work will be made to compare our LMIC KBP models with those made at a HIC academic radiotherapy center.

Impact of AI-Based Auto-Segmentation on Radiotherapy Processes in Low and Middle-Income Countries

PURPOSE/OBJECTIVE(S)

Radiotherapy processes require significant human resources and expertise, creating a barrier for rapid deployment in low and middle-income countries (LMICs). Optimal radiotherapy (RT) relies on accurate segmentation of tumor targets and organs-at-risk (OARs) during the RT planning process. This study reports the impact of AI-based auto-segmentation on RT processes in an LMIC.

MATERIALS/METHODS

Ten patients including five head and neck (HN), and five prostate cancer patients were randomly selected. Their planning CT images were subjected to auto- segmentation using an FDA-approved AI software tool, and manual segmentation by an experienced radiation oncologist from a Sub-Saharan African RT clinic. The control data consisted of contours from an experienced radiation oncologist and dosimetrists at a large academic institution in the US. For prostate cases, the contours included the prostate, seminal vesicles, bladder, rectum, penile bulb, and both femoral heads. For HN cases, the contours included the brain, brainstem, bilateral eyes, lens, optic nerves, cochlea, parotids, optic chiasm, spinal cord, oral cavity, and mandible. The time to complete the segmentation was recorded for both auto-segmentation and manual contours from the LMIC. The DICE similarity coefficients were used for comparative evaluation.

RESULTS

The average time for contouring per patient was 2 minutes for AI compared to 57 minutes for manual contouring in the LMIC. When comparing the control data, AI pelvic contours provide a slightly better agreement than LMIC manual contours for all the OARs, with the following mean DICE coefficients for AI vs LMIC manual contours: bladder (0.971 vs 0.958), left femoral head (0.960 vs 0.949), right femoral head (0.959 vs 0.941), rectum (0.880 vs 0.867), prostate (0.836 vs 0.824), seminal vesicles (0.696 vs 0.580), and penile bulb (0.536 vs 0.528). For HN contours, AI provide a better agreement for 7 of 11 OARs than the LMIC manual contours, with the following mean DICE coefficients: brain (0.972 vs 0.982), mandible (0.877 vs 0.925), right parotid (0.847 vs 0.800), left parotid (0.798 vs 0.792), spinal cord (0.837 vs 0.821), left eye (0.875 vs 0.832), right eye (0.867 vs 0.836), brainstem (0.866 vs 852), oral cavity (0.796 vs 0.787), left lens (0.650 vs 0.729) and right lens (0.671 vs 0.682). Neither AI contours nor LMIC manual contours had good agreement with the control data (<0.600) for optic nerves, chiasm, and cochlea due to their small volumes.

CONCLUSION

AI-based auto-segmentation tools are capable of producing contours of comparable quality to those generated by manual segmentation for both pelvic and HN cancer patients in LMICs, while also resulting in substantial time savings. AI-based auto-segmentation holds tremendous potential for improving radiotherapy care in LMICs with limited sources.

Application of Nanozymes and its Progress in the Treatment of Ischemic Stroke

Nanozymes are a new kind of material which has been applied since the beginning of this century, and its birth has promoted the development of chemistry, materials science, and biology. Nanozymes can be used as a substitute for natural enzyme and has a wide range of applications; therefore, it has attracted extensive attention from all sectors of the community, and the number of studies has constantly increasing. In this paper, we introduced the outstanding achievements in the field of nanozymes in recent years from the main function, the construction of nanozyme-based biosensors, and the treatment of ischemic stroke, and we also illustrated the internal mechanism and the catalytic principle. In the end, the obstacles and challenges in the future development of nanozymes were proposed.

[Evolution and progress of surgical intervention strategies for acute pancreatitis]

Acute pancreatitis is one of the common surgical acute abdominal diseases. Since people first recognized acute pancreatitis in the middle of the nineteenth century, a diversified minimally invasive treatment model with standardization has been formed today. According to the main line of surgical intervention of acute pancreatitis treatment,this period can be roughly divided into five stages:exploration stage, conservative treatment stage, pancreatectomy stage, debridement and drainage of the pancreatic necrotic tissue stage, and minimally invasive treatment as the first choice led by the multidisciplinary team mode stage. Throughout history, the evolution and progress of surgical intervention strategies for acute pancreatitis cannot be separated from the progress of science and technology, the update of treatment concepts and the further understanding of the pathogenesis. This article will summarize the surgical characteristics of acute pancreatitis treatment at each stage to explain the development of surgical treatment of acute pancreatitis,to help investigate the development of surgical treatment of acute pancreatitis in the future.

Application of Nanotechnology-Based Products in Stroke

Stroke is a disease with high disability and high mortality in the world. Due to the existence of the blood-brain barrier (BBB), complex brain structure, and numerous neural signal pathways, the treatment methods are limited, so new drugs and new treatments need to be developed urgently. Thankfully, the advent of nanotechnology offered a new opportunity for biomedical development because of the unique properties of nanoparticles that give them the ability to traverse the BBB and accumulate in relevant regions of the brain. More importantly, nanoparticles could be modified on the surface to meet a variety of specific properties that people need. Some could be used for effective drug delivery, including tissue plasminogen activator (tPA), neuroprotective agents, genes, and cytokines; some nanoparticles were used as contrast agents and biosensors in medical imaging for further diagnosis of stroke; some were used to track target cells for prognosis of stroke; and some were used to detect pathological markers of stroke that appear at different stages. This Review looks at the application and research progress of nanoparticles in the diagnosis and treatment of stroke, hoping to bring some help to researchers.

[Application of veno-arterio-venous extracorporeal membrane oxygenation in patients with critical respiratory failure combined with refractory shock]

Objective: To preliminarily analyze the application experience of veno-arterio-venous extracorporeal membrane oxygenation (VAV-ECMO).The VAV-ECMO is a rescue strategy for patients with extremely critical respiratory failure combined with refractory shock. Methods: From February 2016 to February 2022, the characteristics and outcomes of patients who were started on either veno-venous or veno-arterial ECMO due to respiratory or hemodynamic failure, and then converted to VAV-ECMO in respiratory intensive care unit (ICU) of Beijing Chaoyang Hospital were analyzed. Results: A total of 15 patients underwent VAV-ECMO, aged 53 (40, 65) years, and 11 of whom were male. Within the group, VV-ECMO was initially used in 12 patients due to respiratory failure, but then VAV-ECMO was used due to cardiogenic shock (7/12) and septic shock (4/12), while VAV-ECMO was established in two patients due to lung transplantation. One patient was diagnosed with pneumonia complicated by septic shock, which was initially determined to be VA-ECMO, but then switched to VAV-ECMO because it was difficult to maintain oxygenation. The time from the establishment of VV or VA-ECMO to the switch to VAV-ECMO was 3 (1, 5) days and the VAV-ECMO support time was 5 (2, 8) days. ECMO-related complications were bleeding, mostly in the digestive tract (n=4) and airway hemorrhage (n=4), without intracranial hemorrhage, and poor arterial perfusion of the lower limbs (n=2). Among these 15 patients, the overall ICU mortality was 53.3%. The mortality of patients who received VAV-ECMO due to septic shock and cardiogenic shock was 100% (4/4) and 42.8% (3/7), respectively. Two patients who received VAV-ECMO due to lung transplantation all survived. Conclusion: VAV-ECMO may be a safe and effective treatment for carefully selected patients with critical respiratory failure associated with cardiogenic shock or end-stage lung disease lung transplantation transition, however, patients with septic shock may benefit the least.

Label-free SERS ultrasensitive and universal detection of low back pain fingerprint based on SERS substrate

Low back pain (LBP) seriously endangers human health and quality of life, and the detection of thoracolumbar fasciitis (TLF) is vital for the prevention and treatment of LBP. Surface-enhanced Raman scattering (SERS) is considered as a powerful technique for fingerprint detection due to the inherent richness of the spectral data. In this work, a novel SERS strategy based on a three-dimensional substrate was developed for fingerprint analysis for early diagnosis of TLF. A rat TLF model was established and the model was evaluated from the immunological and behavioral perspectives. Vibrational fingerprints were obtained by SERS testing of isolated fascial tissue and were used to explore the material changes during fasciitis. SERS spectra were analyzed using principal component analysis (PCA) that allowed unambiguous distinction and monitoring of component changes during TLF. Furthermore, in order to further clarify the occurrence and development of TLF, we combined clinical samples for analysis, and investigated the inflammatory factor expression levels of CRP and SAA in TLF. Our results demonstrated that tryptophan, phenylalanine and glycogen could unambiguously distinguish TLF as confirmed by SERS analysis, a method that is capable of noninvasive characterization of and diagnosis of TLF during LBP. We have provided a new tool that may promote in-depth study of the mechanism and treatment of fasciitis.

Prussian Blue Nanozyme Treatment of Ischemic Brain Injury via Reducing Oxidative Stress Inhibits Inflammation, Suppresses Apoptosis, and Promotes Neurological Recovery

Ischemic stroke is one of the leading causes of death and severe disability. The overproduction of reactive oxygen species (ROS) after ischemic injury causes a series of inflammatory reactions, which is considered to be the key factor in aggravating brain injury. However, the current clinical drug treatment effect is not satisfactory. Therefore, ROS scavengers that can remove excess ROS production have great therapeutic potential. Nanoenzymes with potent antioxidant stress and anti-inflammatory properties have the potential to treat ischemic stroke. Herein, we used a Prussian blue nanoenzyme (PBzyme) to study the treatment of ischemic stroke. The comprehensive effects of PBzyme on ROS in vivo and in vitro were investigated. Pbzyme inhibited the activation of macrophages and the release of inflammatory factors in the brain, promoted the polarization of microglia to M2, inhibited neuronal apoptosis, and promoted the recovery of neurological function after ischemic stroke. This research may provide a promising application for nanoenzymes to treat brain diseases.

[The mechanism, inducement and long-term effects of acquired weakness in intensive care units]

With the development of critical care medicine, the case fatality rate in intensive care units (ICU) patients has decreased significantly, but most patients still suffer from the long-term problems of related complications after discharge, which seriously affects the quality of life and social integration after discharge. Complications such as ICU acquired weakness (ICU-AW) and Post-ICU Syndrome (PICS) are not uncommon throughout the treatment of severe patients. The treatment of critically ill patients should not only focus on the treatment of the disease, but also gradually extend to the whole-process physiological-psychological-social medical intervention mode in the ICU, during the stay in the general ward and after discharge. On the basis of ensuring patient safety, patients' physical and psychological status assessment in the early stage of ICU admission, and disease prevention as soon as possible, which can reduce the long-term impact on the quality of life and social work after discharge.

Semiparametric Efficient G-estimation with Invalid Instrumental Variables

The instrumental variable method is widely used in the health and social sciences for identification and estimation of causal effects in the presence of potential unmeasured confounding. In order to improve efficiency, multiple instruments are routinely used, leading to concerns about bias due to possible violation of the instrumental variable assumptions. To address this concern, we introduce a new class of G-estimators that are guaranteed to remain consistent and asymptotically normal for the causal effect of interest provided that a set of at least γ out of K candidate instruments are valid, for γ≤K set by the analyst ex ante, without necessarily knowing the identity of the valid and invalid instruments. We provide formal semiparametric efficiency theory supporting our results. Both simulation studies and applications to the UK Biobank data demonstrate the superior empirical performance of our estimators compared to competing methods.

SERS "hot spot" enhance-array assay for misfolded SOD1 correlated with white matter lesions and aging

Misfolding of superoxide dismutase-1 (SOD1) has been correlated with many neurodegenerative diseases, such as Amyotrophic lateral sclerosis's and Alzheimer's among others. However, it is unclear whether misfolded SOD1 plays a role in another neurodegenerative disease of white matter lesions (WMLs). In this study, a sensitive and specific method based on SERS technique was proposed for quantitative detection of misfolded SOD1 content in WMLs. To fabricate the double antibodysandwich substrates for SERS detection, gold nanostars modified with capture antibody were immobilized on glass substrates to prepare active SERS substrates, and then SERS probes conjugated with a Raman reporter and a specific target antibody were coupled with active SERS substrates. This SERS substrates had been employed for quantitative detection of misfolded SOD1 levels in WMLs and exhibited excellent stability, reliability, and accuracy. Moreover, experimental results indicated that the level of misfolded SOD1 increased with the increase in age and the degree of WMLs. Hence, misfolded SOD1 may be a potential blood marker for WMLs and aging. Meanwhile, SERS-based gold nanostars have great clinical application potential in the screening, diagnosis and treatment of WMLs.

Administration of intramuscular AAV-BDNF and intranasal AAV-TrkB promotes neurological recovery via enhancing corticospinal synaptic connections in stroke rats

Stroke causes long-term disability in survivors. BDNF/TrkB plays an important role in synaptic plasticity and synaptic transmission in the central nervous system (CNS), promoting neurological recovery. In this study, we performed non-invasive treatment methods focused on intramuscular injection into stroke-injured forelimb muscles, or intranasal administration using adeno-associated virus (AAV) vectors carrying genes encoding BDNF or TrkB. In a permanent rat middle cerebral artery occlusion (MCAO) model, we assessed the effects of combination therapy with AAV-BDNF and AAV-TrkB on motor functional recovery and synaptic plasticity of the corticospinal connections. Our results showed that BDNF or TrkB gene transduced in the spinal anterior horn neurons and cerebral cortical neurons. Compared to AAV vector treatment alone, behavioral and electrophysiological results showed that the combination therapy significantly improved upper limb motor functional recovery and neurotransmission efficiency after stroke. BDA tracing, immunofluorescence staining, qRT-PCR, and transmission electron microscopy of synaptic ultrastructure results revealed that the combination therapy not only potently increased the expression of Synapsin I, PSD-95, and GAP-43, but also promoted the axonal remodeling and restoration of abnormal synaptic structures. These findings provide a new strategy for enhancing neural plasticity and a potential means to treat stroke clinically.

Single-cell RNA sequencing of peripheral blood reveals that monocytes with high cathepsin S expression aggravate cerebral ischemia-reperfusion injury

BACKGROUND

Stroke is a major cause of morbidity and mortality worldwide. After cerebral ischemia, peripheral immune cells infiltrate the brain and elicit an inflammatory response. However, it is not clear when and how these peripheral immune cells affect the central inflammatory response, and whether interventions that target these processes can alleviate ischemia-reperfusion (I/R) injury.

METHODS

Single-cell transcriptomic sequencing and bioinformatics analysis were performed on peripheral blood of mice at different times after I/R to analyze the key molecule of cell subsets. Then, the expression pattern of this molecule was determined through various biological experiments, including quantitative RT-PCR, western blot, ELISA, and in situ hybridization. Next, the function of this molecule was assessed using knockout mice and the corresponding inhibitor.

RESULTS

Single-cell transcriptomic sequencing revealed that peripheral monocyte subpopulations increased significantly after I/R. Cathepsin S (Ctss)was identified as a key molecule regulating monocyte activation by pseudotime trajectory analysis and gene function analysis. Next, Cathepsin S was confirmed to be expressed in monocytes with the highest expression level 3 days after I/R. Infarct size (p < 0.05), neurological function scores (p < 0.05), and apoptosis and vascular leakage rates were significantly reduced after Ctss knockout. In addition, CTSS destroyed the blood-brain barrier (BBB) by binding to junctional adhesion molecule (JAM) family proteins to cause their degradation.

CONCLUSIONS

Cathepsin S inhibition attenuated cerebral I/R injury; therefore, cathepsin S can be used as a novel target for drug intervention after stroke.

Rapid magnetic separation: An immunoassay platform for the SERS-based detection of subarachnoid hemorrhage biomarkers

The blood–brain barrier (BBB) is of vital importance to the progression and prognosis of subarachnoid hemorrhage (SAH). The construction of a simple, sensitive, and accurate detection assay for measuring the biomarkers associated with BBB injury is still an urgent need owing to the complex pathogenesis of SAH and low expression levels of pathological molecules. Herein, we introduced surface-enhanced Raman scattering (SERS) label-embedded Fe₃O₄@Au core-shell nanoparticles as ideal SERS sensors for quantitative double detection of MMP-9 and occludin in SAH patients. Meanwhile, utilizing the SERS signals to dynamically estimate MMP-9 and occludin concentration in the rat SAH model is the first application in exploring the relationship of pathological MMP-9 and occludin molecular levels with neurobehavioral score. This method warrants reliable detection toward MMP-9 and occludin with a wide recognition range and a low detection limit in blood samples. Furthermore, the results monitored by the SERS assay exactly matched with those obtained through a traditional enzyme-linked immunosorbent assay (ELISA). The aforementioned results demonstrated this novel biosensor strategy has extensive application prospects in the quantitative measurement of multiple types of biomolecules in body fluid samples.

[Clinical characteristics and outcomes of acute respiratory distress syndrome caused by severe Chlamydia psittaci pneumonia]

Objective: To investigate the clinical characteristics and outcomes of acute respiratory distress syndrome (ARDS) caused by Chlamydia psittaci pneumonia. Methods: From June 2016 to January 2021, 10 cases were diagnosed as severe Chlamydia psittaci pneumonia induced ARDS in Intensive Care Unit of Respiratory and Critical Care Medicine Department (RICU) of Beijing Chao-Yang Hospital Affiliated to Capital Medical University. We collected the clinical data including clinical features, laboratory tests, imaging and outcomes of the patients. Results: The pathogenic diagnosis was confirmed by metagenomic Next-generation Sequencing (mNGS) in these 10 patients, with a median age of 59 (46, 67) years. In addition to high fever, cough and dyspnea, the patients also had multiple organ involvement. Six patients had elevated peripheral leukocyte count, 10 cases had increased type B natriuretic peptide, 7 cases had increased aspartate aminotransferase/alanine aminotransferase, 9 cases had hyponatremia and 3 cases had elevated creatinine. The imaging findings were bilateral consolidation with air bronchogram and infiltrates, and pleural effusion were found in 5 cases. All cases were combined with respiratory failure. Six patients received invasive mechanical ventilation. Nine patients received moxifloxacin and one patient was administrated with Azithromycin. All the patients were improved and discharged after the treatment, and the mean duration of RICU stay was 13.5 (11, 16.7) days. One month follow-up of nine patients showed significant improvement in lung lesions. Conclusions: Severe Chlamydia psittiaci pneumonia may be complicated with respiratory failure and/or multiple organ involvement. For severe pneumonia with an exposure history of sick birds, the possibility of Chlamydia psittaci infection should be considered. mNGS may help etiological diagnosis. All patients in this study had a good prognosis after targeted treatment.

Quantitative and Noninvasive Detection of SAH-Related MiRNA in Cerebrospinal Fluids In Vivo Using SERS Sensors Based on Acupuncture-Based Technology

Quantitative analysis of microRNAs (miRNAs) in a noninvasive manner is of vital importance for disease diagnosis and prognosis evaluation. However, conventional strategies for realizing accurate, simple, and sensitive detection of target molecules are still a challenge, especially for miRNAs due to their low abundance and susceptibility in the complex biological environment. Here, a novel surface-enhanced Raman scattering (SERS) strategy was established for quantitative detection and monitoring of miRNA-21-5p (miR-21-5p) in living cells and in vivo cerebrospinal fluid (CSF) by applying hairpin DNA (hpDNA)-conjugated gold nanostars (GNSs) SERS probes combined with acupuncture-based technology. This strategy enabled ultrasensitive exploration toward miR-21-5p in a wide range from 1 fM to 100 pM in cell lysates. Moreover, SERS analysis facilitated the detection and long-term monitoring for in vivo miR-21-5p noninvasively. This developed strategy promises to offer a powerful method for the analysis of multiple biomolecules in single cells and living bodies.

Vented Individual Patient (VIP) Hoods for the Control of Infectious Airborne Diseases in Healthcare Facilities

By providing a means of separating the airborne emissions of patients from the air breathed by healthcare workers (HCWs), vented individual patient (VIP) hoods, a form of local exhaust ventilation (LEV), offer a new approach to reduce hospital-acquired infection (HAI). Results from recent studies have demonstrated that, for typical patient-emitted aerosols, VIP hoods provide protection at least equivalent to that of an N95 mask. Unlike a mask, hood performance can be easily monitored and HCWs can be alerted to failure by alarms. The appropriate use of these relatively simple devices could both reduce the reliance on personal protective equipment (PPE) for infection control and provide a low-cost and energy-efficient form of protection for hospitals and clinics. Although the development and deployment of VIP hoods has been accelerated by the coronavirus disease 2019 (COVID-19) pandemic, these devices are currently an immature technology. In this review, we describe the state of the art of VIP hoods and identify aspects in need of further development, both in terms of device design and the protocols associated with their use. The broader concept of individual patient hoods has the potential to be expanded beyond ventilation to the provision of clean conditions for individual patients and personalized control over other environmental factors such as temperature and humidity.

[Novel MFN2, BSCL2 and LRSAM1 variants in a cohort of Chinese patients with Charcot-Marie-Tooth disease]

Objective: Charcot-Marie-Tooth disease (CMT) comprises a group of clinically and genetically heterogeneous inherited neuropathies with an estimated prevalence of 1 in 2500. This study aimed to analyze the clinical and mutational characteristics of Chinese CMT patients with MFN2, BSCL2 and LRSAM1 variants. Methods: In this study, genetic analysis was performed in 206 Chinese patients at Chinese PLA General Hospital from December 2012 to March 2020 with clinical diagnosis of CMT, and reported variants of MFN2, BSCL2 and LRSAM1 related to CMT2. Results: We reported ten MFN2 mutations in ten unrelated patients (7 male, 3 female), two of whom had positive family history. Three novel mutations were detected including c.475-2A>G (splicing); c.687dupA (p.E230Rfs*16) and c.558dupT (p.S186fs). We reported three BSCL2 mutations of four unrelated patients, including c.461C>G (p.S154W), c.461C>T(p.S154L), and novel variants of c.1309G>C (p.A437P) and c.845C>T (p.A282V). Furthermore, two novel variants of LRSAM1, including c.1930G>T (p.G644C) and c.1178T>A (p.L393Q) were detected in two unrelated patients. Conclusion: Mutational spectrum of MFN2-, BSCL2-and LRSAM1-related CMT disease is expanded with the identification of novel variants in Chinese patients.

[Analysis of China's influenza vaccine application policy based on the macro model of the health system]

This article uses the analysis framework of the macro model of the health system to analyze the influenza vaccine policy documents issued by the state and governments at all levels from three perspectives: structure, process and results, and provides a scientific basis for improving the application strategy of influenza vaccine. It is suggested that on the basis of continuing to strengthen publicity, mobilization and organizational guarantee, measures to promote the application of influenza vaccine in China by exploring multi-channel financing mechanisms, combining the experience of new crown vaccination to improve the convenience of influenza vaccination, and scientifically setting vaccination rate targets, improve preparedness for an influenza pandemic.

[Weaning of veno-venous extracorporeal membrane oxygenation: when to use the "resting lung"]

Differences in weaning strategies for veno-venous extracorporeal membrane oxygenation (VV-ECMO) are based on expert opinions rather than clinical evidence. Therefore, each center has its own "unique skills". The timing of VV-ECMO weaning has not received due attention. It is difficult to find research on the choice of VV-ECMO weaning timing in the database. There are few studies involving VV-ECMO that describe the weaning process in detail. At present, the weaning process of VV-ECMO is mainly based on expert opinions. This article classified the current VV-ECMO weaning strategies, appealed to a unified VV-ECMO weaning protocol in China as soon as possible, and further improved the prognosis of patients with extracorporeal life support.

[Treatment choices for infected pancreatic necrosis:surgery debridement or endoscopy drainage?]

Infected pancreatic necrosis (IPN) is a crucial reason for the poor prognosis of patients with acute pancreatitis,which is complicated and difficult to predict the outcomes. Surgery is an important way to cure IPN,and "step-up approach" is the mainstream mode of IPN treatment. In the era of minimally invasive surgery,the full course endoscopic treatment of IPN has been gradually hot and achieved good outcomes as endoscopic technology' improvement. However,it is controversial that whether technique is better for IPN by surgery debridement or endoscopy drainage,and there is no consensus on the scope of applicability and the timing of intervention. The paper aims to explore the intervention methods,indications and timing of endoscopic and surgical treatment of IPN and elaborate the selection strategies of them in clinical practice,so as to develop individualized treatment options,accurately implement minimally invasive intervention and improve the prognosis.

[SWOT analysis of influenza vaccination promotion of primary care staff based on the perspective of the supplier, customer, and management]

Objective: To analyze the situation of influenza vaccination among primary healthcare workers, find out the problems, and explore the strategies and measures to promote influenza vaccination among grass-roots medical staff. Methods: From April to May 2021, key insider interviews and literature research were carried out based on the perspectives of influenza vaccine suppliers (influenza vaccine manufacturers), consumers (primary medical institutions and primary healthcare workers), and managers (governments at all levels, health administrative departments and disease prevention and control departments). The SWOT (strengths, weaknesses, opportunities, and threats) analysis technique was used to comprehensively evaluate the current situation of influenza vaccination among grass-roots healthcare workers, and a SWOT analysis matrix was established. Results: Influenza vaccination of grass-roots healthcare workers have advantages and opportunities, including primary medical and health institutions' vital influenza vaccination accessibility, influenza vaccine safety is higher, COVID-19 outbreak improves the public awareness of respiratory infectious diseases and vaccine production enthusiasm, coronavirus vaccination has strengthened the capacity of the vaccine distribution system. There are also disadvantages and threats such as the high price of influenza vaccine, insufficient supply, low awareness of influenza vaccine vaccination among grass-roots healthcare workers, lack of demand assessment mechanism on influenza vaccine, poor vaccine deployment, structural imbalance in vaccine supply in different areas, and severe vaccine waste. SWOT analysis matrix of the influenza vaccination status of grass-roots healthcare workers was established, forming dominant opportunity (SO) strategy, dominant threat (ST) strategy, inferior opportunity (WO) strategy, and inferior threat (WT) strategy. Conclusion: Measures should be taken by the supplier, the demand-side, and the management side to improve the influenza vaccine coverage rate of primary healthcare workers, but the emphasis should be on the coordination and management of the management side.

MiR-572 promotes the development of non-small cell lung cancer by targeting KLF2

OBJECTIVE

The aim of this study was to uncover the role of miR-572 in regulating proliferative and migratory abilities in non-small cell lung cancer (NSCLC) and the possible mechanism.

PATIENTS AND METHODS

Expression levels of miR-572 in 46 matched NSCLC and paracancerous samples were detected. The relationship between miR-572 level and clinical features of NSCLC was analyzed. Subsequently, the regulatory effects of miR-572 on proliferative and migratory abilities in lung cancer cells were assessed by functional experiments. Finally, the downstream genes of miR-572 were tested by luciferase assay, and their functions in the development of NSCLC were finally explored by rescue experiments.

RESULTS

It was found that miR-572 was upregulated in NSCLC samples. High level of miR-572 predicted high rates of lymphatic and distant metastases, as well as poor prognosis in NSCLC. Besides, the knockdown of miR-572 suppressed proliferative and migratory abilities in A549 and SPC-A1 cells. KLF2 was identified to be the downstream gene of miR-572, which was involved in the regulation of NSCLC phenotypes influenced by miR-572.

CONCLUSIONS

MiR-572 is closely linked to metastasis and prognosis in NSCLC patients, and it promotes the malignant development of NSCLC via targeting KLF2.