Rictor/mTORC2 signalling contributes to renal vascular endothelial-to-mesenchymal transition and renal allograft interstitial fibrosis by regulating BNIP3-mediated mitophagy.

BACKGROUND: Renal allograft interstitial fibrosis/tubular atrophy (IF/TA) constitutes the principal histopathological characteristic of chronic allograft dysfunction (CAD) in kidney-transplanted patients. While renal vascular endothelial-mesenchymal transition (EndMT) has been verified as an important contributing factor to IF/TA in CAD patients, its underlying mechanisms remain obscure. Through single-cell transcriptomic analysis, we identified Rictor as a potential pivotal mediator for EndMT. This investigation sought to elucidate the role of Rictor/mTORC2 signalling in the pathogenesis of renal allograft interstitial fibrosis and the associated mechanisms. METHODS: The influence of the Rictor/mTOR2 pathway on renal vascular EndMT and renal allograft fibrosis was investigated by cell experiments and Rictor depletion in renal allogeneic transplantation mice models. Subsequently, a series of assays were conducted to explore the underlying mechanisms of the enhanced mitophagy and the ameliorated EndMT resulting from Rictor knockout. RESULTS: Our findings revealed a significant activation of the Rictor/mTORC2 signalling in CAD patients and allogeneic kidney transplanted mice. The suppression of Rictor/mTORC2 signalling alleviated TNFα-induced EndMT in HUVECs. Moreover, Rictor knockout in endothelial cells remarkably ameliorated renal vascular EndMT and allograft interstitial fibrosis in allogeneic kidney transplanted mice. Mechanistically, Rictor knockout resulted in an augmented BNIP3-mediated mitophagy in endothelial cells. Furthermore, Rictor/mTORC2 facilitated the MARCH5-mediated degradation of BNIP3 at the K130 site through K48-linked ubiquitination, thereby regulating mitophagy activity. Subsequent experiments also demonstrated that BNIP3 knockdown nearly reversed the enhanced mitophagy and mitigated EndMT and allograft interstitial fibrosis induced by Rictor knockout. CONCLUSIONS: Consequently, our study underscores Rictor/mTORC2 signalling as a critical mediator of renal vascular EndMT and allograft interstitial fibrosis progression, exerting its impact through regulating BNIP3-mediated mitophagy. This insight unveils a potential therapeutic target for mitigating renal allograft interstitial fibrosis.

NSD2 modulates Drp1-mediated mitochondrial fission in chronic renal allograft interstitial fibrosis by methylating STAT1.

Renal interstitial fibrosis/tubular atrophy (IF/TA) is a prominent pathological feature of chronic allograft dysfunction (CAD). Our previous study has demonstrated that epithelial-mesenchymal transition (EMT) plays a significant role in shaping the development of IF/TA. Nuclear SET domain (NSD2), a histone methyltransferase catalyzing methylation at lysine 36 of histone 3, is crucially involved in the development and progression of solid tumors. But its role in the development of renal allograft interstitial fibrosis has yet to be elucidated. Here, we characterize NSD2 as a crucial mediator in the mouse renal transplantation model in vivo and a model of tumor necrosis factor-α (TNF-α) stimulated-human renal tubular epithelial cells (HK-2) in vitro. Functionally, NSD2 knockdown inhibits EMT, dynamin-related protein 1 (Drp1)-mediated mitochondrial fission in mice. Conversely, NSD2 overexpression exacerbates fibrosis-associated phenotypes and mitochondrial fission in tubular cells. Mechanistically, tubular NSD2 aggravated the Drp-1 mediated mitochondrial fission via STAT1/ERK/PI3K/Akt signaling pathway in TNF-α-induced epithelial cell models. Momentously, mass spectrometry (MS) Analysis and site-directed mutagenesis assays revealed that NSD2 interacted with and induced Mono-methylation of STAT1 on K173, leading to its phosphorylation, IMB1-dependent nuclear translocation and subsequent influence on TNF-α-induced EMT and mitochondrial fission in NSD2-dependent manner. Collectively, these findings shed light on the mechanisms and suggest that targeting NSD2 could be a promising therapeutic approach to enhance tubular cell survival and alleviate interstitial fibrosis in renal allografts during CAD.

Intraoperative evaluation of local cerebral hemodynamic change by laser speckle contrast imaging for predicting postoperative cerebral hyperperfusion during STA-MCA bypass in adult patients with moyamoya disease.

Cerebral hyperperfusion (CHP) occurred frequently after direct superficial temporal artery-middle cerebral artery (STA-MCA) bypass surgery for moyamoya disease (MMD). We analyzed cortical microvascular density (CMD) and the change of cerebral blood flow (LΔCBF) using intraoperative laser speckle contrast imaging (LSCI) on 130 hemispheres of 95 consecutive adult patients with MMD. The demographic characteristics, cortical hemodynamic sources, bypass methods, intraoperative blood flow data, and relative CBF changes on single-photon emission computed tomography (SPECT) examination (SΔrCBF) were compared between the groups with and without CHP. The median values for CMD, LΔCBF, and SΔrCBF were significantly higher in the CHP group than in the non-CHP group (CMD 0.240 vs 0.206, P = 0.004; LΔCBF 2.285 vs 1.870, P < 0.001; SΔCBF 1.535 vs 1.260, P < 0.001). Multivariate analysis revealed that hemodynamic sources of recipient parasylvian cortical arteries from MCA (M-PSCAs), end-to-side (E-S) bypass method, CMD ≥ 0.217, and LΔCBF ≥ 1.985 were the risk factors for CHP. Intraoperative LSCI was useful for evaluating hemodynamics and predicting CHP in patients with MMD.

The efficacy and safety of anti-EGFR target agents in patients with potentially resectable metastatic colorectal cancer: a meta-analysis of randomized controlled trials.

BACKGROUND: Adding anti-epidermal growth factor receptor (anti-EGFR) target agents to conversion therapy may improve the resection rates and survival of patients with potentially resectable metastatic colorectal cancer (mCRC). This study aims to analyze the efficacy and safety of additional anti-EGFR target agents. METHODS: A systematic search was conducted on PubMed, Web of Science, Embase, and Cochrane Library. And all relevant studies published in English before January 2023 were collected to explore the impact of additional anti-EGFR targeted agent on the efficacy and safety of patients with potentially resectable mCRC (PROSPERO: CRD42022340523, https://www.crd.york.ac.uk/PROSPERO/ ). RESULTS: This study included a total of 8 articles, including 2618 patients. The overall response rate (ORR) and R0 resection rates of the experimental group were higher than those of the control group, while there was no significant difference in progression-free survival (PFS) and overall survival (OS) between the two groups. In RAS/KRAS wild-type patients, the ORR (RR: 1.20, 95% Cl: 1.02-1.41, p = 0.03), R0 resection rate (RR: 1.60, 95% Cl: 1.17-2.20, p = 0.003), PFS (HR: 0.80, 95% Cl: 0.68-0.93, p = 0.003), and OS (HR: 0.87, 95% Cl: 0.76-0.99, p = 0.031) of the experimental group were higher than those of the control group. While in KRAS mutant patients, there was no statistical difference between the two groups in ORR, R0 resection rate, PFS, and OS. CONCLUSION: The addition of anti-EGFR targeted agents can improve the prognosis of RAS/KRAS wild-type patients with potentially resectable mCRC, while KRAS mutant patients may not benefit. In addition, the overall safety factor was controllable.

Analyzing characteristics of collateral flow to parasylvian cortical arteries by three-dimensional digital subtraction angiography-magnetic resonance angiography fusion imaging in adult moyamoya disease.

Objective: The hemodynamic sources of recipient parasylvian cortical arteries (PSCAs) were significantly related to postoperative cerebral hyperperfusion (CHP) after bypass surgery in patients with moyamoya disease (MMD). The present study aimed to introduce a new method to investigate the characteristics of PSCAs hemodynamic sources and their relationships with clinical presentations in adult MMD and to provide preoperative evaluation for recipient vessel selection in MMD bypass surgery. Methods: The hemodynamic sources of the PSCAs in 171 symptomatic MMD hemispheres were analyzed by three-dimensional digital subtraction angiography (3D-DSA) combined with magnetic resonance angiography (MRA) fusion imaging. The spatial and temporal characteristics of the hemodynamic sources of the PSCAs and their associations with the patient's demographics, Suzuki stage, and initial onset type were investigated. Results: Six major types of hemodynamic sources in the PSCAs were observed. There was a significant difference between the hemodynamic sources of the PSCAs above and below the SF (P < 0.001). With advancing Suzuki stages, collateral flow to the PSCAs above the SF from the internal carotid arteries (ICAs) significantly decreased, while the non-ICAs increased (P < 0.001). Multivariate analysis revealed that hemodynamic sources of the PSCAs above the SF were significantly associated with patients' initial onset type (P = 0.026). Conclusion: In MMD hemispheres, the hemodynamic sources of the PSCAs above the SF are more varied than those below the SF and present a typical conversion trend from ICAs to non-ICAs with advancing Suzuki stages. Analyzing the hemodynamic sources of the PSCAs can help in understanding the conversion pattern of compensatory vascular systems, predicting episodes in MMD, and preoperatively evaluating suitable recipient vessel selection for bypass surgery to avoid postoperative CHP.

Semaglutide Pretreatment Induces Cardiac Autophagy to Reduce Myocardial Injury in Septic Mice.

BACKGROUND: Sepsis-induced myocardial dysfunction (SIMD) confers substantial morbidity and mortality. Semaglutide treatment has demonstrated efficacy in ameliorating sepsis-related organ damage via attenuation of inflammation, oxidative stress, and apoptotic cell death. In this study, we constructed a mouse SIMD model using cecal ligation and puncture (CLP) to explore whether semaglutide preconditioning can modulate autophagy levels and attenuate myocardial injury. METHODS: C57BL/6 mice were randomly divided into six groups: sham, CLP (including CLP-6 h, CLP-12 h and CLP-24 h subgroups), semaglutide, and semaglutide+Compound-C, with five mice in each group. The latter two groups were given daily intraperitoneal injections of semaglutide for 14 days. The semaglutide+Compound-C group was given the autophagy inhibitor Compound-C intraperitoneally 1-hour before CLP surgery. After the last injection of semaglutide, SIMD mouse models were constructed by CLP surgery, while the sham group underwent a sham operation. All mice were sacrificed after surgery, and blood and myocardial specimens were collected. Enzyme-linked immunosorbent assay (ELISA) was used to measure the levels of inflammatory factors and myocardial injury markers in the serum, while quantitative real-time polymerase chain reaction (qRT-PCR) and western blot was used to detect the expression of autophagic markers [microtubule-associated protein 1A/1B-light chain 3B (LC3B), Beclin-1, p62] and AMP-activated protein kinase (AMPK) in myocardial tissue. Hematoxylin and eosin (H&E) staining was used to observe pathological changes in myocardial tissue. RESULTS: The myocardial fibers in the sham group were normal, while those in the CLP group showed disordered arrangement, interstitial edema, and a large number of infiltrating inflammatory cells. A few vacuolar changes were observed locally in the semaglutide group, and more vacuolar changes were observed in the semaglutide+Compound-C group. Autophagy was inhibited in the CLP group mice. Compared with the CLP group, the semaglutide group showed a decreased levels of inflammatory factors (tumor necrosis factor-α, interleukin-1ß) and myocardial injury markers (creatine kinase isoenzyme, cardiac troponin T) in the serum, a reduced expression of autophgic substrate p62, and an increased expression of LC3II (the lipidated form of LC3I)/LC3I (microtubule-associated protein 1A/1B-light chain 3), Beclin-1, and p-AMPK (phosphorylated AMP-activated protein kinase)/AMPK in the injured myocardial tissues of mice (p < 0.05). And the protective effects of semaglutide against SIMD were partially reversed by the treatment of AMPK inhibitor Compound-C (p < 0.05). CONCLUSIONS: Taken together, these data indicate that semaglutide provides protection against CLP-triggered myocardial inflammation and injury, potentially by reactivating myocardial autophagy pathways via activation of AMPK signaling. Further mechanistic studies are needed to definitively elucidate the functional significance of AMPK signaling in mediating the beneficial cardiac effects of semaglutide during sepsis.

A Cell Surface-Binding Antibody Atlas Nominates a MUC18-Directed Antibody-Drug Conjugate for Targeting Melanoma.

Recent advances in targeted therapy and immunotherapy have substantially improved the treatment of melanoma. However, therapeutic strategies are still needed for unresponsive or treatment-relapsed patients with melanoma. To discover antibody-drug conjugate (ADC)-tractable cell surface targets for melanoma, we developed an atlas of melanoma cell surface-binding antibodies (pAb) using a proteome-scale antibody array platform. Target identification of pAbs led to development of melanoma cell killing ADCs against LGR6, TRPM1, ASAP1, and MUC18, among others. MUC18 was overexpressed in both tumor cells and tumor-infiltrating blood vessels across major melanoma subtypes, making it a potential dual-compartment and universal melanoma therapeutic target. AMT-253, an MUC18-directed ADC based on topoisomerase I inhibitor exatecan and a self-immolative T moiety, had a higher therapeutic index compared with its microtubule inhibitor-based counterpart and favorable pharmacokinetics and tolerability in monkeys. AMT-253 exhibited MUC18-specific cytotoxicity through DNA damage and apoptosis and a strong bystander killing effect, leading to potent antitumor activities against melanoma cell line and patient-derived xenograft models. Tumor vasculature targeting by a mouse MUC18-specific antibody-T1000-exatecan conjugate inhibited tumor growth in human melanoma xenografts. Combination therapy of AMT-253 with an antiangiogenic agent generated higher efficacy than single agent in a mucosal melanoma model. Beyond melanoma, AMT-253 was also efficacious in a wide range of MUC18-expressing solid tumors. Efficient target/antibody discovery in combination with the T moiety-exatecan linker-payload exemplified here may facilitate discovery of new ADC to improve cancer treatment. SIGNIFICANCE: Discovery of melanoma-targeting antibodies using a proteome-scale array and use of a cutting-edge linker-payload system led to development of a MUC18-targeting antibody-exatecan conjugate with clinical potential for treating major melanoma subtypes.

Disruption of RCAN1.4 expression mediated by YY1/HDAC2 modulates chronic renal allograft interstitial fibrosis.

Chronic allograft dysfunction (CAD) is a major factor that hinders kidney transplant survival in the long run. Epithelial-mesenchymal transition (EMT) has been confirmed to significantly contribute to interstitial fibrosis/tubular atrophy (IF/TA), which is the main histopathological feature of CAD. Aberrant expression of the regulator of calcineurin 1 (RCAN1), recognized as an endogenous inhibitor of the calcineurin phosphatase, has been shown to be extensively involved in various kidney diseases. However, it remains unclear how RCAN1.4 regulates IF/TA formation in CAD patients. Herein, an in vivo mouse renal transplantation model and an in vitro model of human renal tubular epithelial cells (HK-2) treated with tumor necrosis factor-α (TNF-α) were employed. Our results proved that RCAN1.4 expression was decreased in vivo and in vitro, in addition to the up-regulation of Yin Yang 1 (YY1), a transcription factor that has been reported to convey multiple functions in chronic kidney disease (CKD). Knocking in of RCAN1.4 efficiently attenuated chronic renal allograft interstitial fibrosis in vivo and inhibited TNF-α-induced EMT in vitro through regulating anti-oxidative stress and the calcineurin/nuclear factor of activated T cells cytoplasmic 1 (NFATc1) signaling pathway. In addition, suppression of YY1 mediated by shRNA or siRNA alleviated TNF-α-induced EMT through abolishing reactive species partly in an RCAN1.4-dependent manner. Notably, we confirmed that YY1 negatively regulated RCAN1.4 transcription by directly interacting with the RCAN1.4 promoter. In addition, histone deacetylase 2 (HDAC2) interacted with YY1 to form a multi-molecular complex, which was involved in TNF-α-induced RCAN1.4 transcriptional repression. Therefore, RCAN1.4 is suggested to be modulated by the YY1/HDAC2 transcription repressor complex in an epigenetic manner, which is a mediated nephroprotective effect partly through modulating O2⋅- generation and the calcineurin/NFATc1 signaling pathway. Thus, the YY1-RCAN1.4 axis constitutes an innovative target for IF/TA treatment in CAD patients.

AMT-562, a Novel HER3-targeting Antibody-Drug Conjugate, Demonstrates a Potential to Broaden Therapeutic Opportunities for HER3-expressing Tumors.

HER3 is a unique member of the EGFR family of tyrosine kinases, which is broadly expressed in several cancers, including breast, lung, pancreatic, colorectal, gastric, prostate, and bladder cancers and is often associated with poor patient outcomes and therapeutic resistance. U3-1402/Patritumab-GGFG-DXd is the first successful HER3-targeting antibody-drug conjugate (ADC) with clinical efficacy in non-small cell lung cancer. However, over 60% of patients are nonresponsive to U3-1402 due to low target expression levels and responses tend to be in patients with higher target expression levels. U3-1402 is also ineffective in more challenging tumor types such as colorectal cancer. AMT-562 was generated by a novel anti-HER3 antibody Ab562 and a modified self-immolative PABC spacer (T800) to conjugate exatecan. Exatecan showed higher cytotoxic potency than its derivative DXd. Ab562 was selected because of its moderate affinity for minimizing potential toxicity and improving tumor penetration purposes. Both alone or in combination therapies, AMT-562 showed potent and durable antitumor response in low HER3 expression xenograft and heterogeneous patient-derived xenograft/organoid models, including digestive system and lung tumors representing of unmet needs. Combination therapies pairing AMT-562 with therapeutic antibodies, inhibitors of CHEK1, KRAS, and tyrosine kinase inhibitor showed higher synergistic efficacy than Patritumab-GGFG-DXd. Pharmacokinetic and safety profiles of AMT-562 were favorable and the highest dose lacking severe toxicity was 30 mg/kg in cynomolgus monkeys. AMT-562 has potential to be a superior HER3-targeting ADC with a higher therapeutic window that can overcome resistance to generate higher percentage and more durable responses in U3-1402-insensitive tumors.

Assessment of plasma soluble Tie-2 level to distinguish moyamoya disease from atherosclerotic cerebrovascular disease and predict postoperative neovascularization.

OBJECTIVE: Moyamoya disease (MMD) is a chronic steno-occlusive cerebrovascular disease and features the formation of hazy collateral vessels at the base of the brain. Angiopoietin (Ang)-1 and -2, their receptor Tie-2, and vascular endothelial growth factor (VEGF) that regulate angiogenesis might be important in MMD pathophysiology and postoperative collateral formation. The goal of this study was to determine whether levels of these angiogenic factors could predict collateralization in patients with MMD. METHODS: A total of 196 patients with MMD and 57 with atherosclerotic cerebrovascular disease serving as controls were enrolled. Ang-1, Ang-2, Tie-2, and VEGF mRNA levels were analyzed in middle cerebral artery (MCA) arterial wall specimens by using real-time quantitative polymerase chain reaction. MCA and peripheral plasma concentrations of Ang-1, Ang-2, soluble Tie-2 (sTie-2), and VEGF were examined by enzyme-linked immunosorbent assay. Cerebral arteriography was performed 6 months after bypass surgery to assess the postoperative collateralization. RESULTS: In MCA specimens, patients with MMD exhibited higher expression levels of Ang-1 and Ang-2 but lowered VEGF expression. The patients with MMD had significantly higher concentrations of Ang-1 and Ang-2 but lower levels of VEGF in MCA plasma. Peripheral plasma concentrations of these growth factors were not changed. MCA and peripheral plasma sTie-2 levels were both reduced in patients with MMD. The 6-month follow-up showed that patients with good collateral formation had lower sTie-2 levels in both MCA and peripheral plasma. Furthermore, the Suzuki stage and peripheral plasma sTie-2 level were significantly correlated with good postoperative collateral formation on multivariate analysis. CONCLUSIONS: Ang-1, Ang-2, Tie-2, and VEGF are involved in MMD pathogenesis. The peripheral plasma level of sTie-2 can differentiate MMD from atherosclerotic cerebrovascular disease and serve as a novel biomarker to predict postoperative collateral formation.

Expression of hypoxia-inducing factor-1α and matrix metalloproteinase-9 in the recipient parasylvian cortical arteries with different hemodynamic sources in adult moyamoya disease.

Objective: In our latest research, we have demonstrated that the recipient parasylvian cortical arteries (PSCAs) with hemodynamic sources from the middle cerebral artery (M-PSCAs) has a higher risk of postoperative cerebral hyperperfusion (CHP) syndrome than those from non-M-PSCAs in adult moyamoya disease (MMD) patient. However, whether there are differences between M-PSCAs and non-M-PSCAs in vascular specimens characteristics has not been studied. In this study, we further investigate the vascular specimen of recipient PSCAs by histological and immunohistochemical methods. Methods: 50 vascular specimens of recipient PSCAs were obtained from 50 adult MMD patients during the combined bypass surgeries in our departments of Zhongnan hospital. 4 recipient PSCAs samples were also obtained in the same way from the middle cerebral artery occlusion patients. The samples were received the pathological sectioning, hematoxylin and eosin staining, and immunohistochemistry, then the vascular wall thickness, matrix metalloproteinase-9 (MMP-9) and hypoxia-inducing factor-1α (HIF-1α) were analyzed. Results: M-PSCAs adult MMD patients had a thinner intima than non-M-PSCAs in the recipient PSCAs specimens. In recipient non-M-PSCAs vascular specimens, the immunoreactivity indicating HIF-1α and matrix metalloproteinase-9 (MMP-9) was significantly higher than M-PSCAs groups. The logistic regression analyses showed that the M-PSCAs was an independent risk factor of postoperative cerebral hyperperfusion (CHP) syndrome (OR 6.235, 95% CI1.018-38.170, P = 0.048) in MMD. Conclusion: Our results indicate that M-PSCAs adult MMD patients had thinner intima than non-MCAs adult MMD patients in the PSCAs. More importantly, HIF-1α and MMP-9 were overexpressed in non-M-PSCAs vascular specimens.

Antibody-Exatecan Conjugates with a Novel Self-immolative Moiety Overcome Resistance in Colon and Lung Cancer.

Antibody-drug conjugates (ADC) using DNA topoisomerase I inhibitor DXd/SN-38 have transformed cancer treatment, yet more effective ADCs are needed for overcoming resistance. We have designed an ADC class using a novel self-immolative T moiety for traceless conjugation and release of exatecan, a more potent topoisomerase I inhibitor with less sensitivity to multidrug resistance (MDR). Characterized by enhanced therapeutic indices, higher stability, and improved intratumoral pharmacodynamic response, antibody-T moiety-exatecan conjugates targeting HER2, HER3, and TROP2 overcome the intrinsic or treatment resistance of equivalent DXd/SN-38 ADCs in low-target-expression, large, and MDR+ tumors. T moiety-exatecan ADCs display durable antitumor activity in patient-derived xenograft and organoid models representative of unmet clinical needs, including EGFR ex19del/T790M/C797S triple-mutation lung cancer and BRAF/KRAS-TP53 double-mutant colon cancer, and show synergy with PARP/ATR inhibitor and anti-PD-1 treatment. High tolerability of the T moiety-exatecan ADC class in nonhuman primates supports its potential to expand the responding patient population and tumor types beyond current ADCs. SIGNIFICANCE: ADCs combining a novel self-immolative moiety and topoisomerase I inhibitor exatecan as payload show deep and durable response in low-target-expressing and MDR+ tumors resistant to DXd/SN-38 ADCs without increasing toxicity. This new class of ADCs has the potential to benefit an additional patient population beyond current options. See related commentary by Gupta et al., p. 817. This article is highlighted in the In This Issue feature, p. 799.

Morphological and Compositional Features of Chronic Internal Carotid Artery Occlusion in MR Vessel Wall Imaging Predict Successful Endovascular Recanalization.

Background: We sought to determine if the morphological and compositional features of chronic internal carotid artery occlusion (CICAO), as assessed by MR vessel wall imaging (MR-VWI), initially predict successful endovascular recanalization. Methods: Consecutive patients with CICAO scheduled for endovascular recanalization were recruited. MR-VWI was performed within 1 week prior to surgery for evaluating the following features: proximal stump morphology, extent of occlusion, occlusion with collapse, arterial tortuosity, the presence of hyperintense signals (HIS) and calcification in the occluded C1 segment. Multivariate logistic regression was used to identify features associated with technical success and construct a prediction model. Results: Eighty-three patients were recruited, of which fifty-seven (68.7%) were recanalized successfully. The morphological and compositional characteristics of CICAO were associated with successful recanalization, including occlusions limited to C1 and extensive HIS, as well as the absence of extensive calcification, absence of high tortuosity, and absence of artery collapse. The MR CICAO score that comprised the five predictors showed a high predictive ability (area under the curve: 0.888, p < 0.001). Conclusion: the MR-VWI characteristics of CICAO predicted the technical success of endovascular recanalization and may be leveraged for identifying patients with a high probability of successful recanalization.

Irregular pulsation of aneurysmal wall is associated with symptomatic and ruptured intracranial aneurysms.

BACKGROUND: Irregular pulsation of aneurysmal wall detected by four-dimensional CT angiography (4D-CTA) has been described as a novel imaging feature of aneurysm vulnerability. Our study aimed to investigate whether irregular pulsation is associated with symptomatic and ruptured intracranial aneurysms (IAs). METHODS: This retrospective study included consecutive patients with IAs who underwent 4D-CTA from January 2018 to July 2021. IAs were categorized as asymptomatic, symptomatic or ruptured. The presence of irregular pulsation (defined as a temporary focal protuberance ≥1 mm on more than three successive frames) was identified on 4D-CTA movies. Univariate and multivariate analyses were used to identify the parameters associated with aneurysm symptomatic or ruptured status. RESULTS: Overall, 305 patients with 328 aneurysms (37 ruptured, 60 symptomatic, 231 asymptomatic) were included. Ruptured and symptomatic IAs were significantly larger in size compared with asymptomatic IAs (median (IQR) 6.5 (5.1-8.3) mm, 7.0 (5.5-9.7) mm vs 4.7 (3.8-6.3) mm, p=0.001 and p<0.001, respectively) and had more irregular pulsations (70.3%, 78.3% vs 28.1%, p<0.05). Irregular pulsation (OR 5.03, 95% CI 2.83 to 8.92; p<0.001) was independently associated with aneurysm symptomatic/ruptured status in the whole population. With unruptured IAs, both irregular pulsation (OR 6.31, 95% CI 3.02 to 13.20; p<0.001) and size (OR 1.17, 95% CI 1.03 to 1.32; p=0.015) were independently associated with the symptoms. The combination of irregular pulsation and size increased the accuracy over size alone in identifying symptomatic aneurysms (AUC 0.81 vs 0.77, p=0.007) in unruptured IAs. CONCLUSION: In a large cohort of patients with IAs detected by 4D-CTA, the presence of irregular pulsation was independently associated with aneurysm symptomatic and ruptured status.

Robotic Arm-Protected Microsurgical Pericallosal and Middle Cerebral Artery Aneurysm Clipping: A Technical Note and Case Series.

BACKGROUND: Managing intraoperative aneurysm rupture (IAR) during intracranial aneurysm clipping can be challenging given the excessive hemorrhage and limited field of view under the microscope for visualizing the proximal artery and safe temporary clipping. OBJECTIVE: To describe the first known use of robotic arm for safeguarding IAR in microsurgical aneurysm clipping. METHODS: A robotic arm was used to safeguard 3 microsurgical clipping cases (1 pericallosal and 2 middle cerebral artery) performed by a single surgeon. The device was installed onto the side rail of the operating table along with the clip applier attachment. After dissecting the cerebral artery segment proximal to the aneurysm, a temporary aneurysm clip was loaded and established at the appropriate segment before dissecting distally toward the aneurysm. RESULTS: Setup for the robotic arm and temporary clip was simple, quick, precise, and without any unforeseen accommodations needed in all 3 instances. The temporary clip acted as an emergency gate and could be deployed either manually or remotely through a controller. IAR occurred in case 1, and the robotic-assisted temporary clip deployment achieved immediate hemostasis without complications. This method bypassed the need for significant suctioning, packing, and further exploration for safe temporary clipping. Case 2 and 3 demonstrated the feasibility for middle cerebral artery protection and ease of intraoperative readjustment. CONCLUSION: This technical note highlights the feasibility and relative ease of using a robotic arm as a safeguard device, and it enables on-demand control of proximal blood flow and may enhance the safety of microsurgical aneurysm procedures.

How to choose the surgical side when cerebral blood flow and cerebrovascular response are contradictory in bilateral moyamoya disease?: A case report.

INTRODUCTION: Moyamoya disease (MMD) is a rare cerebrovascular disease characterized by progressive occlusion of the internal carotid artery and the secondary formation of collateral vessels. Bypass surgery is an effective treatment for MMD. Comprehensive evaluation of cerebral blood flow (CBF) and cerebrovascular response (CVR) is the common hemodynamic indication to surgery, the changes of which are usually identical. THE PATIENTS MAIN CONCERNS AND IMPORTANT EXAMINATIONS: We reported a rare case of MMD in a 34-year-old pregnant woman with transient ischemic attacks (TIAs) for 1 month, manifesting as frequent weakness in right limbs for several minutes without obvious cause. The diagnostic digital subtraction angiography (DSA) examination revealed Suzuki Grade I in left side and Grade IV in right side under modified Suzuki scoring. No-hyperventilation test single-photon emission computed tomography (no-HVT SPECT) showed more decreased CBF in the right side of the brain, but HVT SPECT demonstrated a more impaired CVR on the left side. Comprehensively, which side should be operated on is confusing when the changes of CVR and CBF are inconsistent. THE MAIN DIAGNOSIS, THERAPEUTICS INTERVENTIONS, AND OUTCOMES: The patient was diagnosed with bilateral MMD and underwent combined bypass surgery on the left side of the brain. The symptoms of admission were completely relieved after surgery and there were no further cerebrovascular events during the follow-up period of 4 months. CONCLUSION: CVR is a primary surgical indication of MMD, especially when the impairment of CVR and CBF are not consistent in the ipsilateral hemisphere. Meanwhile, HVT is the vital vasoactive challenges test for measuring CVR in MMD.

IRF1/ZNF350/GPX4-mediated ferroptosis of renal tubular epithelial cells promote chronic renal allograft interstitial fibrosis.

Renal interstitial fibrosis and tubular atrophy are essential pathological characteristics of chronic renal allograft dysfunction (CAD). Herein, we revealed that ferroptosis of renal tubular epithelial cells (RTECs) might contribute to renal tubular injury in CAD. Mechanistically, TNF-α induced ferroptosis by inhibiting GPX4 transcription through upregulating IRF1 in RTECs. IRF1 could bind with ZNF350 to form a transcription factor complex, which directly binds to the GPX4 promoter region to inhibit GPX4 transcription. Ferroptotic RTECs might secrete profibrotic factors, including PDGF-BB and IL-6, to activate neighboring fibroblasts to transform into myofibroblasts or induce EMT in adjacent RTECs. In conclusion, our results confirmed a novel role of ferroptosis in renal tubular injury and interstitial fibrosis, thereby providing insights into the pathogenesis of chronic renal allograft interstitial fibrosis during CAD.

A new neurosurgical adjustable pressure suction apparatus with a mechanically controlled air inlet: the study of precise regulation and atraumatic suction.

Background: An essential surgical tool in neurosurgery is the suction tube. The skillful and accurate use of a suction tube facilitates the neurosurgical operation. Objective: This study is to verify the practicality of an adjustable pressure suction tube (APS tube) and to explore the ideal APS tube diameter and tip negative pressure for different intracranial structures. Methods: APS tubes were used to aspirate brain tissues and carotid arteries of rats. Laser speckle contrast imaging (LSCI) was used to record the blood flow velocity (BFV). We measured APS tube diameter, air inlet size, tip negative pressure and central negative pressure and calculated the correlation between them. In our department, intraoperative real-time parameters including APS tube diameter, length, air inlet size, and central negative pressure were recorded, and the tube tip negative pressure suitable for different intracranial structures and parts was calculated. Results: All experiments were carried out using APS tubes. Experiments on rats objectively reflected a severe structural damage to the brain and blood vessels by the suction tube, which might even result in an irreversible reduction in blood flow., Rat carotid arteries and brain tissue suffered severe damage when the tip negative pressure exceeded 33.4 ± 1.8 and 29.2 ± 2.0 kPa, respectively. BFV failed to return to the preoperative level 3 min after the operation (p < 0.05), and this decrease was more pronounced when the suction tube diameter was large (p < 0.05). The tip negative pressure was positively and negatively correlated with central negative pressure and the air inlet size, and was independent of APS tube diameter. A total of 50 operations including 39 tumor resection operations and 11 moyamoya disease bypass operations were recorded. Large-diameter APS tubes (3.5 mm) with an closed air inlet were frequently used to maintain a greater tip negative pressure before the incision of dura mater. When important structures such as motor cortex and brainstem were involved, 1.5- or 2.0-mm-diameter APS tubes were mostly used, and an air inlet was opened up to 0.7-2.1 mm to maintain a safe tip negative pressure (7.4-27.9 kPa). Conclusion: APS tubes with a mechanical knob provide stable and precise adjustment of the tip negative pressure, avoiding excessive negative pressure that causes serious damage to the intracranial structure. And, this allows the surgeon to hold the suction tube more freely and operate at any angle with an appropriate fulcrum near the incision to achieve efficient atraumatic suction and enhance surgical safety.

The contralateral progression in a cohort of Chinese adult patients with unilateral moyamoya disease after revascularization: a single-center long-term retrospective study.

BACKGROUND: Moyamoya disease (MMD) is a chronic progressive cerebrovascular disease mainly existing in the Asian population, which can be divided into unilateral and bilateral types. Contralateral progression has been reported in pediatric patients with unilateral MMD, while large series about contralateral progression in Chinese adult patients were rare. The goal of this study is to elucidate the clinical features and incidence of contralateral progression in Chinese MMD adult patients. METHODS: One hundred one Chinese adult patients with unilateral MMD who received surgery treatments between January 2015 and January 2017 in our hospital were enrolled in this study. This study contained 89 patients. Digital subtraction angiography was performed in all patients for initial diagnosis, and magnetic resonance angiography was repeated 6 months from the initial operation and then annually. Clinical characteristics, contralateral progression, and risk factors were studied. Previous related studies were also reviewed and meta-analyzed. RESULTS: Of these 89 patients, contralateral progression was identified in 8 patients (9.0%) within a median follow-up period of 63 months, which was lower than that in previous studies (25.9%). Single-factor analysis and multivariate analysis did not reveal significant risk factors related to the contralateral progression. CONCLUSION: The progress rate in this cohort of Chinese adult patients with unilateral MMD after revascularization was 9.0%, which indicates that some of the unilateral MMD were an early form of bilateral MMD rather than a separate condition. TRIAL REGISTRATION: This work was approved by the Medical Ethics Committee of Zhongnan Hospital of Wuhan University (approval number: Kelun-2017005).