Large-Scale Whole-Genome Sequencing of Three Diverse Asian Populations in Singapore.

Underrepresentation of Asian genomes has hindered population and medical genetics research on Asians, leading to population disparities in precision medicine. By whole-genome sequencing of 4,810 Singapore Chinese, Malays, and Indians, we found 98.3 million SNPs and small insertions or deletions, over half of which are novel. Population structure analysis demonstrated great representation of Asian genetic diversity by three ethnicities in Singapore and revealed a Malay-related novel ancestry component. Furthermore, demographic inference suggested that Malays split from Chinese ∼24,800 years ago and experienced significant admixture with East Asians ∼1,700 years ago, coinciding with the Austronesian expansion. Additionally, we identified 20 candidate loci for natural selection, 14 of which harbored robust associations with complex traits and diseases. Finally, we show that our data can substantially improve genotype imputation in diverse Asian and Oceanian populations. These results highlight the value of our data as a resource to empower human genetics discovery across broad geographic regions.

Reconstruction of the full transmission dynamics of COVID-19 in Wuhan.

As countries in the world review interventions for containing the pandemic of coronavirus disease 2019 (COVID-19), important lessons can be drawn from the study of the full transmission dynamics of its causative agent-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)- in Wuhan (China), where vigorous non-pharmaceutical interventions have suppressed the local outbreak of this disease1. Here we use a modelling approach to reconstruct the full-spectrum dynamics of COVID-19 in Wuhan between 1 January and 8 March 2020 across 5 periods defined by events and interventions, on the basis of 32,583 laboratory-confirmed cases1. Accounting for presymptomatic infectiousness2, time-varying ascertainment rates, transmission rates and population movements3, we identify two key features of the outbreak: high covertness and high transmissibility. We estimate 87% (lower bound, 53%) of the infections before 8 March 2020 were unascertained (potentially including asymptomatic and mildly symptomatic individuals); and a basic reproduction number (R0) of 3.54 (95% credible interval 3.40-3.67) in the early outbreak, much higher than that of severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS)4,5. We observe that multipronged interventions had considerable positive effects on controlling the outbreak, decreasing the reproduction number to 0.28 (95% credible interval 0.23-0.33) and-by projection-reducing the total infections in Wuhan by 96.0% as of 8 March 2020. We also explore the probability of resurgence following the lifting of all interventions after 14 consecutive days of no ascertained infections; we estimate this probability at 0.32 and 0.06 on the basis of models with 87% and 53% unascertained cases, respectively-highlighting the risk posed by substantial covert infections when changing control measures. These results have important implications when considering strategies of continuing surveillance and interventions to eventually contain outbreaks of COVID-19.

Using off-target data from whole-exome sequencing to improve genotyping accuracy, association analysis and polygenic risk prediction.

Whole-exome sequencing (WES) has been widely used to study the role of protein-coding variants in genetic diseases. Non-coding regions, typically covered by sparse off-target data, are often discarded by conventional WES analyses. Here, we develop a genotype calling pipeline named WEScall to analyse both target and off-target data. We leverage linkage disequilibrium shared within study samples and from an external reference panel to improve genotyping accuracy. In an application to WES of 2527 Chinese and Malays, WEScall can reduce the genotype discordance rate from 0.26% (SE= 6.4 × 10-6) to 0.08% (SE = 3.6 × 10-6) across 1.1 million single nucleotide polymorphisms (SNPs) in the deeply sequenced target regions. Furthermore, we obtain genotypes at 0.70% (SE = 3.0 × 10-6) discordance rate across 5.2 million off-target SNPs, which had ~1.2× mean sequencing depth. Using this dataset, we perform genome-wide association studies of 10 metabolic traits. Despite of our small sample size, we identify 10 loci at genome-wide significance (P < 5 × 10-8), including eight well-established loci. The two novel loci, both associated with glycated haemoglobin levels, are GPATCH8-SLC4A1 (rs369762319, P = 2.56 × 10-12) and ROR2 (rs1201042, P = 3.24 × 10-8). Finally, using summary statistics from UK Biobank and Biobank Japan, we show that polygenic risk prediction can be significantly improved for six out of nine traits by incorporating off-target data (P < 0.01). These results demonstrate WEScall as a useful tool to facilitate WES studies with decent amounts of off-target data.

Feasible intervention combinations for achieving a safe exit of the Zero-COVID policy in China and its determinants: an individual-based model study.

BACKGROUND: Although several pathways have been proposed as the prerequisite for a safe phase-out in China, it is not clear which of them are the most important for keeping the mortality rate low, what thresholds should be achieved for these most important interventions, and how the thresholds change with the assumed key epidemiological parameters and population characteristics. METHODS: We developed an individual-based model (IBM) to simulate the transmission of the Omicron variant in the synthetic population, accounting for the age-dependent probabilities of severe clinical outcomes, waning vaccine-induced immunity, increased mortality rates when hospitals are overburdened, and reduced transmission when self-isolated at home after testing positive. We applied machine learning algorithms on the simulation outputs to examine the importance of each intervention parameter and the feasible intervention parameter combinations for safe exits, which is defined as having mortality rates lower than that of influenza in China (14.3 per 100, 000 persons). RESULTS: We identified vaccine coverage in those above 70 years old, number of ICU beds per capita, and the availability of antiviral treatment as the most important interventions for safe exits across all studied locations, although the thresholds required for safe exits vary remarkably with the assumed vaccine effectiveness, as well as the age structure, age-specific vaccine coverage, community healthcare capacity of the studied locations. CONCLUSIONS: The analytical framework developed here can provide the basis for further policy decisions that incorporate considerations about economic costs and societal impacts. Achieving safe exits from the Zero-COVID policy is possible, but challenging for China's cities. When planning for safe exits, local realities such as the age structure and current age-specific vaccine coverage must be taken into consideration.

Genetic Admixture in the Culturally Unique Peranakan Chinese Population in Southeast Asia.

The Peranakan Chinese are culturally unique descendants of immigrants from China who settled in the Malay Archipelago ∼300-500 years ago. Today, among large communities in Southeast Asia, the Peranakans have preserved Chinese traditions with strong influence from the local indigenous Malays. Yet, whether or to what extent genetic admixture co-occurred with the cultural mixture has been a topic of ongoing debate. We performed whole-genome sequencing (WGS) on 177 Singapore (SG) Peranakans and analyzed the data jointly with WGS data of Asian and European populations. We estimated that Peranakan Chinese inherited ∼5.62% (95% confidence interval [CI]: 4.76-6.49%) Malay ancestry, much higher than that in SG Chinese (1.08%, 0.65-1.51%), southern Chinese (0.86%, 0.50-1.23%), and northern Chinese (0.25%, 0.18-0.32%). A sex-biased admixture history, in which the Malay ancestry was contributed primarily by females, was supported by X chromosomal variants, and mitochondrial (MT) and Y haplogroups. Finally, we identified an ancient admixture event shared by Peranakan Chinese and SG Chinese ∼1,612 (95% CI: 1,345-1,923) years ago, coinciding with the settlement history of Han Chinese in southern China, apart from the recent admixture event with Malays unique to Peranakan Chinese ∼190 (159-213) years ago. These findings greatly advance our understanding of the dispersal history of Chinese and their interaction with indigenous populations in Southeast Asia.

Systemic exosomal miR-193b-3p delivery attenuates neuroinflammation in early brain injury after subarachnoid hemorrhage in mice.

BACKGROUND: Inflammation is a potential crucial factor in the pathogenesis of subarachnoid hemorrhage (SAH). Circulating microRNAs (miRNAs) are involved in the regulation of diverse aspects of neuronal dysfunction. The therapeutic potential of miRNAs has been demonstrated in several CNS disorders and is thought to involve modulation of neuroinflammation. Here, we found that peripherally injected modified exosomes (Exos) delivered miRNAs to the brains of mice with SAH and that the potential mechanism was regulated by regulation of neuroinflammation. METHODS: Next-generation sequencing (NGS) and qRT-PCR were used to define the global miRNA profile of plasma exosomes in aSAH patients and healthy controls. We peripherally injected RVG/Exos/miR-193b-3p to achieve delivery of miR-193b-3p to the brain of mice with SAH. The effects of miR-193b-3p on SAH were assayed using a neurological score, brain water content, blood-brain barrier (BBB) injury, and Fluoro-Jade C (FJC) staining. Western blotting analysis, enzyme-linked immunosorbent assay (ELISA), and qRT-PCR were used to measure various proteins and mRNA levels. RESULTS: NGS and qRT-PCR revealed that four circulating exosomal miRNAs were differentially expressed. RVG/Exos exhibited improved targeting to the brains of SAH mice. MiR-193b-3p suppressed the expression and activity of HDAC3, upregulating the acetylation of NF-κB p65. Finally, miR-193b-3p treatment mitigated the neurological behavioral impairment, brain edema, BBB injury, and neurodegeneration induced by SAH, and reduced inflammatory cytokine expression in the brains of mice after SAH. CONCLUSIONS: Exos/miR-193b-3p treatment attenuated the inflammatory response by acetylation of the NF-κB p65 via suppressed expression and activity of HDAC3. These effects alleviated neurobehavioral impairments and neuroinflammation following SAH.

Treatment of ruptured middle cerebral artery aneurysms by endovascular approach: a single-center experience.

PURPOSE: The optimal treatment modalities of ruptured middle cerebral artery aneurysm are still controversial. The objective of this study is to analyze the outcomes of patients with ruptured middle cerebral artery aneurysms treated by endovascular coiling. MATERIALS AND METHODS: From October 2011 to October 2015, 67 patients with 71 ruptured middle cerebral artery aneurysms received endovascular coiling in our hospital. We retrospectively reviewed the clinical, radiologic records and outcomes. RESULTS: Of all the 71 aneurysms (67 patients), 42 were treated by coil embolization merely, 27 by stent-assisted coiling and 2 unruptured aneurysms in patients with bilateral middle cerebral artery aneurysms without receiving treatment. Complete occlusion was achieved in 82.6% (57/69) of all the procedures. Each of incomplete and partial occlusion rates was 8.7% (6/69). Intraoperative rupture of aneurysms occurred in two procedures (2.9%). Thrombogenesis occurred in eight procedures (11.6%). Brain infarction occurred in eight patients (11.9%). Post-operative rebleeding occurred in seven patients (10.4%). Sixty-three patients were followed at a mean follow-up of 8.24 ± 7.16 months. The mortality and good outcome rate were 3.2% and 90.5%, respectively. Aneurysm recurrence occurred in 6 (13.3%) of the 45 aneurysms at a mean follow-up of 8.44 ± 7.83 months. CONCLUSIONS: Endovascular coiling is effective for patients with ruptured middle cerebral artery aneurysms. Individualized treatment should be assessed by experienced specialist. It is essential to perform randomized large trials to confirm the efficiency of endovascular coiling.

Healthy lifestyle and essential metals attenuated association of polycyclic aromatic hydrocarbons with heart rate variability in coke oven workers.

Whether adopting healthy lifestyles and maintaining moderate levels of essential metals could attenuate the reduction of heart rate variability (HRV) related to polycyclic aromatic hydrocarbons (PAHs) exposure are largely unknown. In this study, we measured urinary metals and PAHs as well as HRV, and constructed a healthy lifestyle score in 1267 coke oven workers. Linear regression models were used to explore the association of healthy lifestyle score and essential metals with HRV, and interaction analysis was performed to investigate the potential interaction between healthy lifestyle score, essential metals, and PAHs on HRV. Mean age of the participants was 41.9 years (84.5% male). Per one point higher healthy lifestyle score was associated with a 2.5% (95% CI, 1.0%-3.9%) higher standard deviation of all normal to normal intervals (SDNN), 2.1% (95% CI, 0.5%-3.6%) higher root mean square of successive differences in adjacent NN intervals (r-MSSD), 4.3% (95% CI, 0.4%-8.2%) higher low frequency, 4.4% (95% CI, 0.2%-8.5%) higher high frequency, and 4.4% (95% CI, 1.2%-7.6%) higher total power, respectively. Urinary level of chromium was positively associated with HRV indices, with the corresponding ß (95% CI) (%) was 5.17 (2.84, 7.50) for SDNN, 4.29 (1.74, 6.84) for r-MSSD, 12.26 (6.08, 18.45) for low frequency, 12.61 (5.87, 19.36) for high frequency, and 11.31 (6.19, 16.43) for total power. Additionally, a significant interaction was found between healthy lifestyle score and urinary total hydroxynaphthalene on SDNN (Pinteraction = 0.04), and higher level of urinary chromium could attenuate the adverse effect of total hydroxynaphthalene level on HRV (all Pinteraction <0.05). Findings of our study suggest adopting healthy lifestyle and maintaining a relatively high level of chromium might attenuate the reduction of HRV related to total hydroxynaphthalene exposure.

The effects and potential mechanisms of essential metals on the associations of polycyclic aromatic hydrocarbons with blood cell-based inflammation markers.

BACKGROUND: Polycyclic aromatic hydrocarbons (PAHs) are well-acknowledged pro-inflammatory chemicals, but their associations with blood cell-based inflammatory biomarkers need further investigation. Moreover, the effects and mechanisms of essential metals on PAH-related inflammation remain poorly understood. OBJECTS: To elucidate the associations of PAHs on inflammatory biomarkers, as well as the effects and mechanisms of essential metals on these associations. METHODS: A cross-sectional study was conducted on 1388 coke oven workers. We analyzed the modification effects of key essential metal(s) on PAHs-inflammatory biomarkers associations. To explore the possible mechanisms from an inflammation perspective, we performed a bioinformatic analysis on the genes of PAHs and essential metals obtained from the Comparative Toxicogenomics Database (CTD) and performed a mediation analysis. RESULTS: We observed associations of PAHs and essential metals with lymphocyte-to-monocyte ratio (LMR) (P < 0.05). PAH mixtures were inversely associated with LMR (ßQGC-index = -0.18, P < 0.001), with 1-hydroxypyrene (1-OH-Pyr) being the most prominent contributor (weight = 63.37%), whereas a positive association between essential metal mixtures and LMR was observed (ßQGC-index = 0.14, P < 0.001), with tin being the most significant contributor (weight = 51.61%). An inverse association of 1-OH-Pyr with LMR was weakened by increased tin exposure (P < 0.05). The CTD database showed that PAHs and tin compounds co-regulated 22 inflammation-associated genes, but they regulated most genes in opposite directions. Further identified the involvement of oxidative stress and mediation analysis showed that the mediation effect of 8-hydroxydeoxyguanosine (8-OHdG) on 1-OH-Pyr-LMR association presented heterogeneity between low and high tin tertile groups (I2 = 37.84%). CONCLUSION: 1-OH-Pyr and tin were significantly associated with LMR. Modification effects indicated that the inverse association of 1-OH-Pyr with LMR was mitigated with an increase in tin. The mediation effect of 8-OHdG on the inverse association of 1-OH-Pyr with LMR may be partially dependent on tin.

Salvianolic acid B ameliorates neuroinflammation and neuronal injury via blocking NLRP3 inflammasome and promoting SIRT1 in experimental subarachnoid hemorrhage.

The nucleotide-binding oligomerization domain (NOD)-like receptor family pyrin domain containing 3 (NLRP3) inflammasome-mediated immuno-inflammatory response plays a critical role in exacerbating early brain injury (EBI) after subarachnoid hemorrhage (SAH). Salvianolic acid B (SalB) has previously been shown to suppress neuroinflammatory responses in many disorders. Meanwhile, a previous study has demonstrated that SalB mitigated oxidative damage and neuronal degeneration in a prechiasmatic injection model of SAH. However, the therapeutic potential of SalB on immuno-inflammatory responses after SAH remains unclear. In the present study, we explored the therapeutic effects of SalB on neuroinflammatory responses in an endovascular perforation SAH model. We observed that SalB ameliorated SAH-induced functional deficits. Additionally, SalB significantly mitigated microglial activation, pro-inflammatory cytokines release, and neuronal injury. Mechanistically, SalB inhibited NLRP3 inflammasome activation and increased sirtuin 1 (SIRT1) expression after SAH. Administration of EX527, an inhibitor of SIRT1, abrogated the anti-inflammatory effects of SalB against SAH and further induced NLRP3 inflammasome activation. In contrast, MCC950, a potent and selective NLRP3 inflammasome inhibitor, reversed the detrimental effects of SIRT1 inhibition by EX527 on EBI. These results indicated that SalB effectively repressed neuroinflammatory responses and neuronal damage after SAH. The action of SalB appeared to be mediated by blocking NLRP3 inflammasome and promoting SIRT1 signaling.

Risk factors of recurrence after endovascular embolization of posterior communicating artery aneurysms.

BACKGROUND AND OBJECTIVE: To determine the risk factors for recurrence after endovascular embolization of posterior communicating artery aneurysms (PcomA). METHODS: We retrospectively analyzed a cohort of 163 patients harboring 172 PocmAs who were treated with endovascular embolization from January 2019 to December 2020. The patients were divided into recurrence and stable groups depending on outcome. Univariate and logistic regression analyses were performed to determine the potential risk factors of recurrence during follow-up. RESULTS: Of the total 163 patients harboring 172 aneurysms, 107 were treated with simple coil occlusion and 65 were treated with stent-assisted coil embolization. There were significant differences in aneurysm sizes and use of non-stent-assisted coil embolizations between the groups (P < 0.05). The incidence of saccular aneurysm and Raymond grade were significantly higher in the recurrent group than in the stable group (P < 0.01). After variable selection, Raymond grade, aneurysm size, saccular aneurysm and non-stent-assisted coil embolization were included in further analysis. Binary logistic regression analysis revealed significant associations with non-stent-assisted coil embolization (P = 0.007), packing density (P < 0.001) and Raymond grades II (P < 0.001) and III (P = 0.002). CONCLUSION: Non-stent-assisted coil embolization, as well as packing density and Raymond grades II grade III are associated with recurrence after endovascular treatment of PcomA.

The Evaluation and Optimization Methods of Villages in China: In the Background of a Rural Revitalization Strategy.

Over the past few decades of rapid development, China has always attached great importance to the redevelopment of rural areas. Since the 19th National Congress of the Communist Party of China, the rural revitalization strategy proposed at the meeting has always received extensive attention. In 2019, the Chinese central government released a document on its rural revitalization strategy. In the document, Guizhou Province was listed as a key area to receive focus on pursuing rural revitalization. Meanwhile, the Guizhou government also formulated The Implementation Opinions on the People's Government of Guizhou Province's Rural Revitalization Strategy. The aim of this paper is to try to establish a model according to the rural revitalization strategy proposed by the Guizhou government and extracts the main influencing factors from its analysis. Through the analysis of the data collected during the process of the rural revitalization, the paper undertakes a deep analysis of the evaluation and studies an optimized approach to the revitalization to provide a referenced review for other villages.

Enterprise 2 Stent-Assisted Embolization of Paraclinoid Aneurysms: A Single Center Preliminary Study.

Objective: Enterprise stent has been widely used for assisted embolization in wide-necked aneurysms while delayed ischemia or thromboembolic complications for its incomplete stent apposition. The purpose of this study was to summarize and analyze the clinical experience of using Enterprise 2 (EP2) stent-assisted embolization in the treatment of paraclinoid aneurysms. Methods: From January 2019 to December 2020, the clinical and imaging data of 98 patients with paraclinoid aneurysms treated with EP2 stent-assisted embolization were enrolled retrospectively. Preliminary experience and follow-up outcomes of EP2 stent-assisted embolization of paraclinoid aneurysms were assessed by using the Raymond grade and modified Rankin Scale. Results: Of the 98 aneurysms, all stents were released satisfactorily. The immediate postprocedural angiography revealed a complete occlusion of the aneurysms with 77.55% of the (76/98) patients, and the last follow-up angiograms showed complete occlusion with 83.67% of the (82/98) patients. The average aneurysm size was (4.11 ± 1.25) mm, the aneurysm diameter was (4.41 ± 1.37) mm, the vessel radius was (3.87 ± 0.32) mm, the diameter at the distal of stent was (3.23 ± 0.21) mm, and the proximal was (4.18 ± 0.23) mm. Among the 98 aneurysms, 13 cases had incomplete stent apposition, 3 cases had intraoperative knotting, and the stents were improved post adjusted; 2 cases had vasospasm and 1 case had stenosis during operation, the symptoms were improved after symptomatic treatment. The result demonstrated that stent length and inner bending radius of parent artery were the pivotal factors affecting incomplete stent apposition (P < 0.01). Conclusion: The EP2 stent for the treatment of paraclinoid aneurysms is safe and effective, however, the length of the stent and the inner bending radius of parent artery are important factors affecting incomplete stent apposition.

Comparison of Enterprise stent 2 with 1 in assisting coiling of ruptured aneurysms: a real-world study.

Aim: To investigate the effectiveness and safety of the Enterprise 2 (E2) stent versus the Enterprise 1 (E1) stent in treating ruptured intracranial aneurysms (RIAs) in China. Materials & methods: The authors conducted an electronic medical record analysis for patients with RIAs who underwent E1/E2 deployment. The main outcomes were immediate complete occlusion (ICO), patient functional outcomes, complications and aneurysm recurrence. Results: Stent deployment was successful in all patients (E2: 90; E1: 270). ICO and patients with good functional outcomes at discharge were similar between E2 and E1 (80.0% vs 75.1% and 78.7% vs 81.1%, respectively). The E2 group had a significantly lower complication rate compared with the E1 group (7.8% vs 16.4%; odds ratio: 0.36; 95% CI: 0.15-0.91; p = 0.031). By 6 months post-discharge, the two groups had comparable patient functional outcomes and aneurysm recurrence (E2 vs E1: 80.2% vs 81.9% and 13.3% vs 14.9%). Conclusion: Compared with the E1 stent, the E2 stent had similar effectiveness but a lower complication risk in treating RIAs.

Endovascular Treatment of Ruptured Very Small Intracranial Aneurysms: Complications, Recurrence Rate, and Clinical Outcomes.

Objective: The aim of this study was to evaluate the safety and efficacy of endovascular treatment for ruptured very small (≤3 mm) intracranial aneurysms (VSIAs). Methods: The clinical data and imaging results for 152 patients with VSIAs treated with coil embolization from August 2014 to June 2020 were retrospectively reviewed. The influential factors related to the preoperative complications, aneurysm recurrence, and clinical outcomes for these patients were analyzed. Results: Among 152 patients with ruptured VSIAs, 90 were treated with coil embolization alone, while 62 were treated with stent-assisted coil embolization. Eighteen patients experienced intra and/or postoperative complications (overall incidence = 11.8%). One person died of intraoperative aneurysm re-rupture and postoperative rebleeding (mortality rate = 0.65%). Twenty patients had various degrees of neurological dysfunction (morbidity rate = 13.1%). Statistical analysis showed that there was no independent risk factor associated with perioperative complications. The rate of complete aneurysm occlusion at discharge and follow-up was 76.3 and 86.2%, respectively. A total of 105 patients underwent digital subtraction angiography during follow-up, and 18 of them experienced postoperative recurrence (recurrence rate = 17.1%). Seven patients were retreated (retreatment rate = 6.7%). The use of stents was the only factor that affected the postoperative recurrence of aneurysm. The incidence of favorable clinical outcomes (Glasgow Outcome Scale score ≥ 4) at discharge and follow-up was 86.2 and 97.1%, respectively. Univariate analysis showed that the preoperative Hunt-Hess grade, CT Fisher grade, and perioperative complications were risk factors for poor clinical outcomes. Multiple logistic regression analysis showed that perioperative complication was the most significant risk factor for the clinical prognosis of patients with ruptured VSIAs. Conclusion: Endovascular treatment is a safe and efficient approach for ruptured VSIAs. Stent-assisted coiling reduced the recurrence rate of aneurysm without increasing the incidence of perioperative complications. The Hunt-Hess grade, CT Fisher grade, and perioperative complications were independent factors associated with the clinical outcomes of patients with ruptured VSIAs, and perioperative complication was the most significant risk factor for poor prognosis in patients.

Hemodynamic Characteristics Associated with Recurrence of Middle Cerebral Artery Bifurcation Aneurysms After Total Embolization.

OBJECTIVE: Hemodynamic parameters are associated with the recurrence of intracranial aneurysms (IAs). Studies showed that high velocity and wall shear stress (WSS) were associated with IAs recurrence after endovascular treatment; nevertheless, factors such as small sample size, locations of IAs, and types of IAs (ie, sidewall or bifurcation) were neglected. The purpose of this study was to identify the hemodynamic characteristics associated with recurrence of middle cerebral artery bifurcation aneurysms (MCABAs) after total embolization by the method of computer fluid dynamics (CFD). METHODS: Following inclusion criteria, we included 92 MCABAs treated with coils only after total embolization from January 2014 to January 2019. We segmented into recurrent and non-recurrent groups according to follow-up digital subtraction angiography (DSA). The MCABA models, including pre-operatively and immediate post-operatively, were reconstructed using 3D-DSAs. The hemodynamic parameters pre-operatively and immediately post-operatively between the groups were calculated and analyzed. RESULTS: There were no significant differences between the recurrent and non-recurrent groups for spatially averaged wall shear stress (SAWSS), maximum wall shear stress (MWSS), velocity, or oscillatory shear index (OSI) at the neck pre-operatively. In the recurrent group, the WSS (22.02±5.11 vs 37.43±8.27 pa, p < 0.001), MWSS (42.59±17.02 vs 66.98±18.61 pa, p=0.014), velocity (0.86±0.19 vs 1.44±0.61 m/s, p=0.01) preoperatively were significantly higher than postoperative values. By contrast, in the non-recurrent group, the WSS (26.53±8.18 vs 22.29±8.64pa, p=0.002), MWSS (42.71±14.01 vs 37.15±15.56 pa, p=0.013), velocity (1.08±0.43 vs 0.23 (0.52, 0.57) m/s, p < 0.001) postoperatively were significantly lower than preoperative values. The OSI, whether in the recurrent group or the non-recurrent group, did not differ significantly between groups (p=0.79 and p=0.19). CONCLUSION: Higher WSS (SAWSS, MWSS) and flow velocity at the aneurysm neck after embolization might be related to recurrence of bifurcation IAs. These might be applied to clinical post-embolization management for the evaluation of bifurcation IAs recanalization.

Neuroprotective effect of helium after neonatal hypoxic ischemia: a narrative review.

Neonatal hypoxic ischemia is one of the leading causes of permanent morbidity and mortality in newborns, which is caused by difficulty in supplying blood and oxygen to brain tissue and is often associated with epilepsy, cerebral palsy, death, short-term or long-term neurological and cognitive impairment. In recent years, the clinical therapeutic effects of noble gases have been gradually discovered and recognized. Numerous studies have shown that noble gases have unique neuroprotective effects to restore damaged nerve and relieve symptoms in patients. Although research on the neuroprotective mechanisms of xenon and argon has yielded a lot of results, studies on helium have stalled. Helium is a colorless, odorless, monoatomic inert gas. The helium has no hemodynamic or neurocognitive side effects and can be used as an ideal pre-adaptor for future clinical applications. In recent years, studies have shown that heliox (a mixture of helium and oxygen) pretreatment can protect the heart, brain, liver and intestine from damage in several animal models, where a variety of signaling pathways have been proved to be involved. There are numerous studies on it even though the mechanism of helium for protecting newborns has not been fully elucidated. It is urgent to find an effective treatment due to the high death rate and disability rate of neonatal hypoxic ischemia. It is believed that helium will be approved safely and effectively for clinical use in the near future.

RAB7L1 Participates in Secondary Brain Injury Induced by Experimental Intracerebral Hemorrhage in Rats.

RAB7, a member of RAS oncogene family-like 1 (RAB7L1), is a GTPase belonging to the Rab family and acts as an upstream regulator to regulate the kinase activity of leucine-rich repeat kinase 2 (LRRK2). Although LRRK2 has been shown to aggravate secondary brain injury (SBI) after intracerebral hemorrhage (ICH), it is unknown whether RAB7L1 is also involved in this process. The purpose of the present study was to investigate the role of RAB7L1 in ICH-induced SBI in vivo. Autologous blood was injected into adult male Sprague-Dawley rats to induce an ICH model in vivo. The results showed that the protein levels of RAB7L1 increased after ICH. Overexpression of RAB7L1 induced neuronal apoptosis and damage, as demonstrated by TUNEL-positive and FJB-positive cells, and exacerbated ICH-induced learning and cognitive dysfunctions; in contrast, downregulation of RAB7L1 via RNA interference yielded comparatively opposite changes in these parameters. In summary, this study demonstrates that RAB7L1 promotes SBI after ICH and may represent a potential target for ICH therapy.

Acyl-CoA synthetase long chain family member 4 plays detrimental role in early brain injury after subarachnoid hemorrhage in rats by inducing ferroptosis.

AIMS: Acyl-CoA synthetase long chain family member 4 (ACSL4) is closely related to tumor genesis and development in certain tissues. However, the function of ACSL4 in early brain injury (EBI) caused by subarachnoid hemorrhage (SAH) is unclear. In this study, we investigated the expression patterns and role of ACSL4 in SAH and post-SAH EBI using a rat model of SAH. METHODS: The rat model of SAH was induced by autologous blood injection into the prechiasmatic cistern of rats. We also used two specific inhibitors of ferroptosis (Ferrostatin-1 and Liproxstatin-1) to investigate the role of ferroptosis in EBI. RESULTS: We found that ACSL4 levels in brain tissue increased significantly in post-SAH EBI. Inhibiting the expression of ACSL4 using small interfering RNAs alleviated inflammation, blood-brain barrier (BBB) impairment, oxidative stress, brain edema, and behavioral and cognitive deficits, and increased the number of surviving neurons, after SAH. Similar effects were obtained by suppressing ferroptosis. CONCLUSIONS: ACSL4 exacerbated SAH-induced EBI by mediating ferroptosis. These findings may provide a theoretical basis for potential therapy aimed at alleviating post-SAH EBI.

Hemodynamic and Morphological Parameters of Ruptured Mirror Posterior Communicating Artery Aneurysms.

Objective: Morphological and hemodynamic parameters might predict rupture of intracranial aneurysms (IAs). A practical model for the study is patients with ruptured mirror IAs in which one is ruptured and the other is unruptured. Although there have been analyses of the morphology and hemodynamics of ruptured mirror posterior communicating artery aneurysms (PComAAs), the sample sizes in these studies were small and only considered hemodynamics or morphological characters. Therefore, this study aimed to investigate the morphological and hemodynamic parameters associated with ruptured mirror PComAAs. Methods: We considered 72 patients with ruptured mirror PComAAs using computational fluid dynamics (CFDs). Ruptured mirror PComAAs were divided into ruptured and unruptured groups. Fourteen morphological and eight hemodynamic parameters were calculated and compared. Significant parameters were analyzed by the multivariate logistic regression to identify independent risk factors. Receiver operating characteristic (ROC) analysis was performed, and the area under the ROC curve (AUC) was calculated for all independent risk factors to determine the predictability and identify the optimal threshold. Results: Four hemodynamic and three morphological parameters were significantly different between ruptured and unruptured groups: normalized wall shear stress (NWSS), mean WSS, low wall shear WSS area (LSA%), size, aspect ratio (AR), size ratio (SR), and inflow angle (IA). Multivariate logistic regression analysis showed that AR, SR, NWSS, mean WSS, and LSA% were all independent factors significantly associated with PComAAs rupture. The ROC analysis for independent risk factors indicated that AR (0.751), NWSS (0.755), mean WSS (0.69), and LSA (0.778) had merely acceptable AUC values. Only SR (0.803) had a high acceptable AUC value. The threshold value of SR was 1.96. Conclusions: SR (>1.96) was the most significant parameter associated with IA rupture, whereas AR, NWSS, mean WSS, and LSA independently characterized the status of IA rupture.