3D-Printed proangiogenic patches of photo-crosslinked gelatin and polyurethane hydrogels laden with vascular cells for treating vascular ischemic diseases.

Engineering vascularized tissues remains a promising approach for treating ischemic cardiovascular diseases. The availability of 3D-bioprinted vascular grafts that induce therapeutic angiogenesis can help avoid necrosis and excision of ischemic tissues. Here, using a combination of living cells and biodegradable hydrogels, we fabricated 3D-printed biocompatible proangiogenic patches from endothelial cell-laden photo-crosslinked gelatin (EC-PCG) bioink and smooth muscle cell-encapsulated polyurethane (SMC-PU) bioink. Implantation of 3D-bioprinted proangiogenic patches in a mouse model showed that EC-PCG served as an angiogenic capillary bed, whereas patterned SMC-PU increased the density of microvessels. Moreover, the assembled patterns between EC-PCG and SMC-PU induced the geometrically guided generation of microvessels with blood perfusion. In a rodent model of hindlimb ischemia, the vascular patches rescued blood flow to distal tissues, prevented toe/foot necrosis, promoted muscle remodeling, and increased the capillary density, thereby improving the heat-escape behavior of ischemic animals. Thus, our 3D-printed vascular cell-laden bioinks constitute efficient and scalable biomaterials that facilitate the engineering of vascular patches capable of directing therapeutic angiogenesis for treating ischemic vascular diseases.

Salidroside Ameliorates Lung Injury Induced by PM 2.5by Regulating SIRT1-PGC-1α in Mice.

Objective: This study aimed to clarify the intervention effect of salidroside (SAL) on lung injury caused by PM 2.5 in mice and illuminate the function of SIRT1-PGC-1ɑ axis. Methods: Specific pathogen-free (SPF) grade male C57BL/6 mice were randomly assigned to the following groups: control group, SAL group, PM 2.5 group, SAL+PM 2.5 group. On the first day, SAL was given by gavage, and on the second day, PM 2.5 suspension was given by intratracheal instillation. The whole experiment consist of a total of 10 cycles, lasting 20 days. At the end of treatment, blood samples and lung tissues were collected and analyzed. Observation of pathological changes in lung tissue using inverted microscopy and transmission electron microscopy. The expression of inflammatory, antioxidants, apoptosis, and SIRT1-PGC-1ɑ proteins were detected by Western blotting. Results: Exposure to PM 2.5 leads to obvious morphological and pathologica changes in the lung of mice. PM 2.5 caused a decline in levels of antioxidant-related enzymes and protein expressions of HO-1, Nrf2, SOD2, SIRT1 and PGC-1ɑ, and an increase in the protein expressions of IL-6, IL-1ß, Bax, caspase-9 and cleaved caspase-3. However, SAL reversed the aforementioned changes caused by PM 2.5 by activating the SIRT1-PGC-1α pathway. Conclusion: SAL can activate SIRT1-PGC-1ɑ to ameliorate PM 2.5-induced lung injury.

A conserved N-terminal motif of CUL3 contributes to assembly and E3 ligase activity of CRL3KLHL22.

The CUL3-RING E3 ubiquitin ligases (CRL3s) play an essential role in response to extracellular nutrition and stress stimuli. The ubiquitin ligase function of CRL3s is activated through dimerization. However, how and why such a dimeric assembly is required for its ligase activity remains elusive. Here, we report the cryo-EM structure of the dimeric CRL3KLHL22 complex and reveal a conserved N-terminal motif in CUL3 that contributes to the dimerization assembly and the E3 ligase activity of CRL3KLHL22. We show that deletion of the CUL3 N-terminal motif impairs dimeric assembly and the E3 ligase activity of both CRL3KLHL22 and several other CRL3s. In addition, we found that the dynamics of dimeric assembly of CRL3KLHL22 generates a variable ubiquitination zone, potentially facilitating substrate recognition and ubiquitination. These findings demonstrate that a CUL3 N-terminal motif participates in the assembly process and provide insights into the assembly and activation of CRL3s.

Dendritic epidermal T cell hydrogel induces the polarization of M2 macrophages to promote the healing of deep tissue pressure injury.

Dendritic epidermal T cells (DETCs) have been shown to promote wound healing. However, the mechanisms involved need to be better understood. In the present study, we investigated the role and mechanism of DETCs in deep tissue pressure injury (DTPI). We established the DTPI model using C57BL/6 mice. Then, DTPI was evaluated and analyzed by histological staining, immunohistochemistry, real-time PCR, Western blotting, and flow cytometry in different treatment groups (DETCs, DETCs/gel, Matrigel, Saline, and Normal group). The results showed that insulin-like growth factor 1 and vascular endothelial growth factor-A expression increased after local DETCs and DETCs/gel implantation in DTPI on days 3 and 7. M1 (inducible nitric oxide synthas-marked) macrophages were predominant at 3 days after DTPI. At 7 days, M1 macrophages were decreased, and M2 (CD206-marked) macrophages were increased in the DETCs and DETCs/gel groups. In vitro, in the co-culture of DETCs and RAW264.7, CD206 expression was significantly increased in M2 macrophages. In addition, Interleukin-17A initially inhibited wound healing 1 day after injury. However, it promoted wound healing at 7, 14, and 21 days after treatment with DETCs and DETCs/gel, respectively. In conclusion, our data suggest that exogenous DETCs improve DTPI wound healing by regulating M1 to M2 macrophage polarization.

The Mediating Role of Self-efficacy and Coping Mode Between Powerlessness and Quality of Life in Patients with Venous Leg Ulcers.

OBJECTIVE: To explore the mediating effect of self-efficacy and coping mode between powerlessness and quality of life in patients with a venous leg ulcer (VLU). METHODS: The authors used a convenience sampling method to select 208 patients with a VLU in four tertiary grade A hospitals in Qingdao and Tianjin from June 2021 to August 2022. Instruments included the Powerlessness Assessment Tool, Venous Leg Ulcer Self-efficacy Tool, Medical Coping Modes Questionnaire, and Venous Leg Ulcer Quality of Life Questionnaire. The authors used descriptive statistics, Pearson correlation, and PROCESS macros for data analysis. RESULTS: The powerlessness score was significantly negatively associated with self-efficacy and confrontation coping mode scores and positively associated with patients' quality-of-life scores. In addition, self-efficacy and confrontation coping modes separately and sequentially mediated the relationship between powerlessness and quality of life. CONCLUSIONS: Self-efficacy and confrontation coping mode play important mediating roles between powerlessness and quality of life in patients with VLUs. By decreasing patients' sense of powerlessness, boosting their self-efficacy, and encouraging them to adopt confrontation coping mode, health professionals can improve patients' quality of life.

COVID-19 increases extracorporeal coagulation during hemodialysis associated with upregulation of vWF/FBLN5 signaling in patients with severe/critical symptoms.

BACKGROUND: COVID-19 has been shown to increase the risk of extracorporeal coagulation during hemodialysis in patients, but the underlying mechanism remains unclear. This study aimed to investigate the effect and mechanism of COVID-19 on the risk of extracorporeal coagulation in patients with chronic kidney disease undergoing hemodialysis. METHODS: A retrospective analysis of the extracorporeal coagulation status of 339 hemodialysis patients at our center before and after COVID-19 infection was performed, including subgroup analyses. Post-infection blood composition was analyzed by protein spectrometry and ELISA. RESULTS: Compared to the pre-COVID-19 infection period, COVID-19-induced extracorporeal coagulation predominantly occurred in patients with severe/critical symptoms. Further proteomic analysis demonstrated that in patients with severe/critical symptoms, the coagulation cascade reaction, platelet activation, inflammation, and oxidative stress-related pathways were significantly amplified compared to those in patients with no/mild symptoms. Notably, the vWF/FBLN5 pathway, which is associated with inflammation, vascular injury, and coagulation, was significantly upregulated. CONCLUSIONS: Patients with severe/critical COVID-19 symptoms are at a higher risk of extracorporeal coagulation during hemodialysis, which is associated with the upregulation of the vWF/FBLN5 signaling pathway. These findings highlight the importance of early anticoagulant therapy initiation in COVID-19 patients with severe/critical symptoms, particularly those undergoing hemodialysis. Additionally, vWF/FBLN5 upregulation may be a novel mechanism for virus-associated thrombosis/coagulation.

Platelet-Rich Plasma in Young and Elderly Humans Exhibits a Different Proteomic Profile.

As people age, their ability to resist injury and repair damage decreases significantly. Platelet-rich plasma (PRP) has demonstrated diverse therapeutic effects on tissue repair. However, the inconsistency of patient outcomes poses a challenge to the practical application of PRP in clinical practice. Furthermore, a comprehensive understanding of the specific impact of aging on PRP requires a systematic investigation. We derived PRP from 6 young volunteers and 6 elderly volunteers, respectively. Subsequently, 95% of high-abundance proteins were removed, followed by mass spectrometry analysis. Data are available via ProteomeXchange with the identifier PXD050061. We detected a total of 739 proteins and selected 311 proteins that showed significant differences, including 76 upregulated proteins in the young group and 235 upregulated proteins in the elderly group. Functional annotation and enrichment analysis unveiled upregulation of proteins associated with cell apoptosis, angiogenesis, and complement and coagulation cascades in the elderly. Conversely, IGF1 was found to be upregulated in the young group, potentially serving as the central source of enhanced cell proliferation ability. Our investigation not only provides insights into standardizing PRP preparation but also offers novel strategies for augmenting the functionality of aging cells or tissues.

Graph modeling of relational structures among functioning variables with low back pain: an exploratory analysis based on international classification of functioning, disability and health.

BACKGROUND: Given the complex etiology, multidimensional impact, and widespread prevalence of low back pain (LBP), it is crucial to prioritize intervention targets based on understanding the relationships between functional impairments in patients. This prioritization maximizes the physical and psychological benefits for patients, and graph modeling holds promise in achieving these objectives. AIM: The aim of this study was establishing a graphical model of functioning variables for LBP based on the International Classification of Functioning, Disability, and Health (ICF) to identify the most influential items (i.e., functioning variables) on the physical and mental well-being of patients. Exploring feasible intervention measures by understanding the dysfunction correlations among these variables. DESIGN: Cross-sectional survey. SETTING: Nine hospitals in Jiangsu Province, China. POPULATION: Three hundred and six persons with LBP aged ≥18 years. METHODS: All patients were assessed using the Comprehensive ICF Core Sets for LBP. The scoring system was converted to dichotomous data, with 1 indicating dysfunction and 0 indicating no dysfunction. In the graphical model, network parameters and the results of Item Response Theory modeling (as detailed in our other article) were used to determine the importance of items, while partial correlations were utilized to estimate the dysfunction correlations between functioning variables. RESULTS: 1) A total of 56 ICF items were located in the backbone structure of LBP, among which d430 (Lifting and carrying objects) occupied the most central position, followed by b126 (Temperament and personality functions). 2) In the main component of backbone structure, d430 has moderate dysfunction correlation with looking after one's health (0.6027), social norms, practices and ideologies (0.597), stability of joint functions (0.5759), and emotional functions (0.4078). b126 has moderate dysfunction correlation with basic interpersonal interactions (0.6595). CONCLUSIONS: d430 and b126 significantly impact the physical and mental well-being of LBP patients. To improve d430, maintaining exercise habits, reducing working hours, enhancing lumbar stability, and overcoming fear-related emotions are recommended. Similarly, improving b126 can be achieved through enhancing interpersonal relationships. CLINICAL REHABILITATION IMPACT: Through the identification of crucial functioning variables and the associated dysfunctional correlation relationships, graphical model of Comprehensive ICF Core Set for LBP can offer healthcare decision-makers valuable insights into potential treatment targets and pathways aimed at improving the condition of LBP patients.

Renal-Limited Thrombotic Microangiopathy in a Patient Who Received Gemcitabine, Ramucirumab, and Pembrolizumab: A Case Report and Literature Review.

Cancer drug-induced thrombotic microangiopathy (DITMA) is an important and serious cause of kidney disease in cancer patients. In addition to classical chemotherapy, the increasing use of targeted therapy and immunotherapy has led to more oncotherapy-associated thrombotic microangiopathy (TMA). It is important for clinicians to recognize this potentially life-threatening adverse effect and gain knowledge of the patient's clinical course and treatment response. In this paper, we report a patient with lung cancer, who was treated with three different classes of anti-neoplastic agents, gemcitabine, ramucirumab, and pembrolizumab. This patient subsequently developed renal-limited thrombotic microangiopathy(rTMA) requiring hemodialysis. The varying features of TMA caused by these therapies were discussed. We also described the clinical course, diagnostic challenges, and management of this patient.

Higher concentration of P7C3 than required for neuroprotection suppresses renal cell carcinoma growth and metastasis.

Background: P7C3 is a novel compound that has been widely applied in neurodegenerative diseases and nerve injury repair. Here, we show that higher concentrations of P7C3 than are required for in vivo neuroprotection have the novel function of suppressing renal cell carcinoma (RCC) proliferation and metastasis. Methods: Colony formation, CCK-8 and EdU assay were applied to evaluate RCC cell proliferation. Wound healing and transwell assay were used to measure RCC cell migration and invasion. Flow cytometry assay was employed to detect RCC cell apoptosis and cell cycle. qRT-PCR assay was carried out to measure ribonucleotide reductase subunit M2 (RRM2) mRNA expression level, while western blot assay was utilized to detect the expression level of target proteins. RCC cell growth in vivo was determined by xenografts in mice. Results: We observed that high concentrations of P7C3 could restrain the proliferation and metastasis of RCC cells and promote cell apoptosis. Mechanistically, this new effect of higher dose of P7C3 was associated with reduced expression of RRM2, and the beneficial efficacy of P7C3 in RCC was blocked when suppression of RRM2 was prevented. When RRM2 suppression was permitted, the cGAS-STING pathway was activated by virtue of RRM2/Bcl-2/Bax signaling. Lastly, intraperitoneal injection of this high level of P7C3 in mice potently inhibited tumor growth. Conclusion: In conclusion, we show here that P7C3 that exerts an anti-cancer effect in RCC. Our study indicated that P7C3 might act as a novel drug for RCC in the future. The regulatory signal pathway RRM2/Bcl-2/BAX/cGAS-STING might present novel insight to the potential mechanism of RCC development.

dECM restores macrophage immune homeostasis and alleviates iron overload to promote DTPI healing.

Due to its highly insidious and rapid progression, deep tissue pressure injury (DTPI) is a clinical challenge. Our previous study found that DTPI may be a skeletal muscle injury dominated by macrophage immune dysfunction due to excessive iron accumulation. Decellularized extracellular matrix (dECM) hydrogel promotes skeletal muscle injury repair. However, its role in polarizing macrophages and regulating iron metabolism in DTPI remains unclear. Here, porcine dECM hydrogel was prepared, and its therapeutic function and mechanism in repairing DTPI were investigated. The stimulus of dECM hydrogel toward RAW264.7 cells resulted in a significantly higher percentage of CD206+ macrophages and notably decreased intracellular divalent iron levels. In mice DTPI model, dECM hydrogel treatment promoted M1 to M2 macrophage conversion, improved iron metabolism and reduced oxidative stress in the early stage of DTPI. In the remodeling phase, the dECM hydrogel remarkably enhanced revascularization and accelerated skeletal muscle repair. Furthermore, the immunomodulation of dECM hydrogels in vivo was mainly involved in the P13k/Akt signaling pathway, as revealed by GO and KEGG pathway analysis, which may ameliorate the iron deposition and promote the healing of DTPI. Our findings indicate that dECM hydrogel is promising in skeletal muscle repair, inflammation resolution and tissue injury healing by effectively restoring macrophage immune homeostasis and normalizing iron metabolism.

Self-Healing Hydrogel Containing Decellularized Liver Matrix and Endothelial Cell-Covered Hepatocyte Spheroids for Rescue of Injured Hepatocytes.

Liver fibrosis occurs in many chronic liver diseases, while severe fibrosis can lead to liver failure. A chitosan-phenol based self-healing hydrogel (CP) integrated with decellularized liver matrix (DLM) is proposed in this study as a 3D gel matrix to carry hepatocytes for possible therapy of liver fibrosis. To mimic the physiological liver microenvironment, DLM is extracted from pigs and mixed with CP hydrogel to generate DLM-CP self-healing hydrogel. Hepatocyte spheroids coated with endothelial cells (ECs) are fabricated using a customized method and embedded in the hydrogel. Hepatocytes injured by exposure to CCl4 -containing medium are used as the in vitro toxin-mediated liver fibrosis model, where the EC-covered hepatocyte spheroids embedded in the hydrogel are co-cultured with the injured hepatocytes. The urea synthesis of the injured hepatocytes reaches 91% of the normal level after 7 days of co-culture, indicating that the hepatic function of injured hepatocytes is rescued by the hybrid spheroid-laden DLM-CP hydrogel. Moreover, the relative lactate dehydrogenase activity of the injured hepatocytes is decreased 49% by the hybrid spheroid-laden DLM-CP hydrogel after 7 days of co-culture, suggesting reduced damage in the injured hepatocytes. The combination of hepatocyte/EC hybrid spheroids and DLM-CP hydrogel presents a promising therapeutic strategy for hepatic fibrosis.

Interaction of vascular endothelial cells with hydrophilic fullerene nanoarchitectured structures in 2D and 3D environments.

The interaction between diverse nanoarchitectured fullerenes and cells is crucial for biomedical applications. Here, we detailed the preparation of hydrophilic self-assembled fullerenes by the liquid-liquid interfacial precipitation (LLIP) method and hydrophilic coating of the materials as a possible vascularization strategy. The interactions of vascular endothelial cells (ECs) with hydrophilic fullerene nanotubes (FNT-P) and hydrophilic fullerene nanowhiskers (FNW-P) were investigated. The average length and diameter of FNT-P were 16 ± 2 µm and 3.4 ± 0.4 µm (i.e. aspect ratios of 4.6), respectively. The average length and diameter of FNW-P were 65 ± 8 µm and 1.2 ± 0.2 µm (i.e. aspect ratios of 53.9), respectively. For two-dimensional (2D) culture after 7 days, the ECs remained viable and proliferated up to ~ 420% and ~ 400% with FNT-P and FNW-P of 50 µg/mL, respectively. Furthermore, an optimized chitosan-based self-healing hydrogel with a modulus of ~400 Pa was developed and used to incorporate self-assembled fullerenes as in vitro three-dimensional (3D) platforms to investigate the impact of FNT-P and FNW-P on ECs within a 3D environment. The addition of FNW-P or FNT-P (50 µg/mL) in the hydrogel system led to proliferation rates of ECs up to ~323% and ~280%, respectively, after 7 days of culture. The ECs in FNW-P hydrogel displayed an elongated shape with aligned morphology, while those in FNT-P hydrogel exhibited a rounded and clustered distribution. Vascular-related gene expressions of ECs were significantly upregulated through interactions with these fullerenes. Thus, the combined use of different nanoarchitectured self-assembled fullerenes and self-healing hydrogels may offer environmental cues influencing EC development in a 3D biomimetic microenvironment, holding promise for advancing vascularization strategy in tissue engineering.

Self-assembled fullerenes with large aspect ratios modulate the morphology and gene expression of endothelial cells within a soft biomimetic 3D microenvironment, representing a promising new vascularization strategy in tissue engineering.

Feasibility of Simultaneous Bilateral Endoscopic Surgery in Prone Split-Leg Position for Bilateral Upper Urinary Tract Calculi: A Pilot Study.

Introduction We explored the viability of simultaneous bilateral endoscopic surgery (SBES) in the prone split-leg position for managing bilateral calculi. Methods We retrospectively reviewed 72 patients who underwent SBES, with procedures involving ureteroscopy (URS) and contralateral percutaneous nephrolithotomy (PNL) simultaneously, in prone split-leg position. Results Operative times averaged 109.38±30.76 minutes, with an average hospital stay of 7.79±3.78 days. Bilateral stone-free rate (SFR) was 70.83%, while URS and PNL demonstrated comparable unilateral SFR (83.33% and 79.17%, respectively). Receiver operating characteristics (ROC) curves for predicting unilateral residual fragments yielded an area under the curve (AUC) of 0.84 (URS) and 0.81 (PNL) with respective cut-off values of stone diameter of 11.55 mm and 23.52 mm. 57 (79.17%) and 15 (20.83%) patients encountered grade 0-1/2 complications, with no severe complications (grade 3-5) recorded. No significant changes in blood count or renal function were observed post-SBES. Conclusions SBES in the prone split-leg position is a viable option for managing bilateral upper-tract urolithiasis. Larger-scale studies are needed to further assess safety and efficacy in various positions.

Genipin inhibits proliferation of gastric cancer cells by inducing ferroptosis: an integrated study of network pharmacology and bioinformatics study.

Ferroptosis has been demonstrated to suppress cancer development and is targeted for cancer therapy. Genipin, an iridoid constituent in Gardeniae Fructus, has been reported to exert anti-cancer abilities. However, whether genipin could induce ferroptosis remains unclear. The purpose of this study is to explore the anti-gastric cancer (GC) effects of genipin by inducing ferroptosis and to identify the potential targets. CCK-8 and colony formation assays were performed to evaluate the anti-GC effects of genipin. Flowcytometry and western blot were used to indicate ferroptosis-inducing ability of genipin. The potential targets of genipin were analyzed by network pharmacology, screened using UALCAN and KM-plotter database and evaluated by molecular docking. The results showed that genipin inhibited cell viability and proliferation of GC cells. Genipin treatment decreased levels of GPX4 and SLC7A11, induced accumulation of lipid peroxidation intracellularly and led to ferroptosis in GC cells. Network pharmacology analysis identified that lipid- and ROS-related pathways involved in ferroptosis ranked high among genipin-GC common targets. Data from UALCAN and KM-plotter database demonstrated that expression levels of ferroptosis-related targets, including AURKA, BCAT2, DHODH, and GPI, increased in GC tissues and the higher levels of the above four targets were related to tumor stage, tumor grade, and poor prognosis. Among these four targets, AURKA, BCAT2, and DHODH were confirmed by molecular docking with binding energies less than - 5. Taken together, our study demonstrates that genipin could exert anti-GC ability by inducing ferroptosis and provides evidence for the potential application of genipin in GC treatment.

Dysfunctional iron metabolism in pressure injuries is related to aberrant CD163 and Homx-1 signal transduction.

Dysregulation of iron metabolism has been associated with impaired chronic wound healing. However, changes in iron metabolism have yet to be reported in pressure injuries, a type of chronic wound. In this study, we aimed to investigate changes in iron metabolism and associated regulatory mechanisms in pressure injuries. We collected tissue biopsies and data from 20 consenting stage IV-pressure injuries patients and 5 non-pressure injuries patients hospitalised at the Affiliated Hospital of Qingdao University between March 2021 and June 2021. In addition, we measured the iron content by inductively coupled plasma mass spectrometry and Prussian blue staining in deep tissue pressure injury mouse models. An Enzyme-linked immune sorbent assay measured the expression of ferritin, ferroportin-1 and transferrin. Immunofluorescence staining, high-throughput transcriptome sequencing, Western blot and RT-qPCR further analysed the fundamental mechanisms regulating iron metabolism. In this study, we observed numerous inflammatory cells infiltrating the marginal tissues of stage IV pressure injury patients and in deep tissue pressure injury models. The expression levels of pro-inflammatory factors, such as inducible nitric oxide synthase and interleukin-6, were significantly increased (p < 0.05). The iron level was proportional to the degree of progression, with the most significant change appearing on the third day in deep tissue pressure injury models (p < 0.05). Enzyme-linked immune sorbent assay results suggested abnormal gene expression was related to iron metabolism, including a substantial increase in ferritin and a significant decrease in the expression of ferroportin-1 (p < 0.05). In addition, immunofluorescence staining and Western blot showed that the expression of macrophage membrane receptor CD163 was abnormally elevated (p < 0.05). Both high-throughput transcriptome sequencing and qRT-PCR results suggested aberrant expression of the CD163/Homx-1-mediated signalling pathway. Dysfunctional iron metabolism was suggested to be related to the aberrant CD163/Homx-1 signalling pathway in deep tissue pressure injury models.

Effectiveness of Rituximab and Its Biosimilar in Treating Adult Steroid-Dependent Minimal Change Disease and Relapse.

Minimal change disease (MCD) is an important cause of nephrotic syndrome in adults. Its course is often complicated by frequent relapses and steroid dependence. Most of the treatment experience of MCD comes from management of pediatric patients rather than adult patients. In this report, the author describes successful experience of using rituximab (RTX) and its biosimilar, RTX-pvvr (ruxience), to treat steroid-dependent MCD and relapses in adult patients. This is the first report of using a RTX biosimilar to treat MCD. This case series demonstrates that RTX and ruxience are well-tolerated, efficacious treatment for managing adult patients with steroid-dependent MCD and relapses.

Clinical outcomes of KRAS-mutant non-small cell lung cancer under untargeted therapeutic regimes in the real world: a retrospective observational study.

Background: Kirsten rat sarcoma viral oncogene homolog (KRAS) mutation seemingly suffered less effective therapeutic regimens in the absence of widely-accepted targeted drugs compared with other mutation types in non-small cell lung cancer (NSCLC). However, whether these non-selective therapy schedules for KRAS mutation matters is still under debate. Correspondingly, we aimed to compare the long term expectancy of indicated therapeutic regimes and further explore the optimal schemes of KRAS mutated NSCLC in the absence of targeted drugs in this retrospective study cohort. Methods: We conducted a single-center retrospective analysis among 66 patients diagnosed with KRAS-mutant advanced NSCLC from November 2018 to December 2020. These enrolled cases were divided into different subgroups in light of mutant isotypes, pathological characteristics, and therapeutic regimes to uncover indicated long-term survival benefits. Additionally, clinical outcomes of treatment schedules and interventional lines to KRAS-mutant NSCLC were described in detail. Results: This cohort enrolled 8 patients with stage IIIB (12.1%) and 58 patients with stage IV (87.9%) with the median age 62 years, ranging from 32 to 91 years old. Genetically, G12C conducted as the most common KRAS mutation type, accounting for 30.3%. Pemetrexed combined with platinum chemotherapy seemed to be a priority (72.7%), and chemotherapy combined with immunotherapy became an alternative (15.2%) in clinic. Performing further analysis of long-term survival of patients receiving different treatment methods indicated that the median overall survival (mOS) in first-line therapy with antiangiogenesis or untreated was 13 and 12 months, respectively (P=0.79). In the first-line regimen, median survival was 17 months for patients who received combined immune checkpoint inhibitors and 12 months for those who did not (P=0.34). The mOS was 20 months for those who had used immune checkpoint inhibitors and 12 months for those who had not (P=0.11). Survival analysis results of NSCLC patients with different KRAS mutation types showed the median survival time of patients with G12C mutation type and patients without with nonG12C mutation type was 19 and 12 months, respectively (P=0.37). Conclusions: In the absence of KRAS targeted drugs, available treatment plans failed to benefit KRAS mutant sufferers regardless of isotypes, making the KRAS-targeted drugs urgent.

Effects of the Degree of Phenol Substitution on Molecular Structures and Properties of Chitosan-Phenol-Based Self-Healing Hydrogels.

Click chemistry is commonly used to prepare hydrogels, and chitosan-phenol prepared by using a Schiff base has been widely employed in the field of biomaterials. Chitosan-phenol is a derivative of chitosan; the phenol groups can disrupt both the inter- and intramolecular hydrogen bonds in chitosan, thereby reducing its crystallinity and improving its water solubility. In addition, chitosan-phenol exhibits various beneficial physiological functions. However, it is still unclear whether the degree of phenol substitution in the chitosan main chain affects the molecular interactions and structural properties of the self-healing hydrogels. To explore this issue, we investigated the molecular structure and network of self-healing hydrogels composed of chitosan-phenol with varying degrees of phenol substitution and dibenzaldehyde poly(ethylene oxide) (DB-PEO) using molecular dynamics simulations. We observed that when the degree of phenol substitution in the self-healing hydrogel was less than 15%, an increase in the degree of phenol substitution led to an increase in the interactions between chitosan-phenol and DB-PEO, and it enhanced the dynamic covalent bond cross-linking generated through the Schiff base reaction. However, when the degree of phenol substitution exceeded 15%, excessive phenol groups caused excessive intramolecular interactions within chitosan-phenol molecules, which reduced the binding between chitosan-phenol and DB-PEO. Our results revealed the influence of the degree of phenol substitution on the molecular structure of the self-healing hydrogels and showed an optimal degree of phenol substitution. These findings provide important insights for the future design of self-healing hydrogels based on chitosan and should help in enhancing the applicability of hydrogels in the field of biomedicine.

Structural insights into the conformational changes of BTR1/SLC4A11 in complex with PIP2.

BTR1 (SLC4A11) is a NH3 stimulated H+ (OH-) transporter belonging to the SLC4 family. Dysfunction of BTR1 leads to diseases such as congenital hereditary endothelial dystrophy (CHED) and Fuchs endothelial corneal dystrophy (FECD). However, the mechanistic basis of BTR1 activation by alkaline pH, transport activity regulation and pathogenic mutations remains elusive. Here, we present cryo-EM structures of human BTR1 in the outward-facing state in complex with its activating ligands PIP2 and the inward-facing state with the pathogenic R125H mutation. We reveal that PIP2 binds at the interface between the transmembrane domain and the N-terminal cytosolic domain of BTR1. Disruption of either the PIP2 binding site or protonation of PIP2 phosphate groups by acidic pH can transform BTR1 into an inward-facing conformation. Our results provide insights into the mechanisms of how the transport activity and conformation changes of BTR1 are regulated by PIP2 binding and interaction of TMD and NTD.