Establishment of a human induced pluripotent stem cell line from a patient with dilated cardiomyopathy.

Dilated cardiomyopathy (DCM) is one of the main causes of sudden cardiac death and heart failure and is the leading indication for cardiac transplantation worldwide. Mutations in dozens of cardiac genes have been connected to the development of DCM including the Troponin T2 gene (TNNT2). Here, we generated a human induced pluripotent stem cells (hiPSCs) from a DCM patient with a familial history that carries a missense mutation in TNNT2. The hiPSCs show typical morphology of pluripotent stem cells, expression of pluripotency markers, normal karyotype, and in vitro capacity to differentiate into all three germ layers.

Comparison between the modified Blalock-Taussig shunt and right ventricular outflow tract stent in the palliative treatment for tetralogy of Fallot. / 改良Blalock-Taussigåˆ†æµæœ¯ä¸Žå³å¿ƒå®¤æµå‡ºé“æ”¯æž¶æ¤å ¥æœ¯å§‘æ¯æ€§æ²»ç–—æ³•æ´›å››è”ç—‡çš„æ¯”è¾ƒ.

OBJECTIVES: For patients with tetralogy of Fallot (TOF) who are not suitable candidates for primary corrective surgery or have a high surgical risk, transcatheter right ventricular outflow tract (RVOT) stent implantation is considered a safe and effective palliative intervention. This study aims to investigate the therapeutic outcomes of RVOT stent implantation in neonates and infants with TOF in comparison with the modified Blalock-Taussig shunt (mBTS) and to compare the impact of the 2 palliative interventions on arterial oxygen saturation and pulmonary artery development in pediatric patients. METHODS: Clinical data of 32 patients with TOF admitted to the Second Xiangya Hospital of Central South University from March 2011 to March 2021 were retrospectively collected. The patients were divided into an mBTS group (undergoing mBTS, n=15) and a stent implantation group (undergoing RVOT stenting, n=17) according to the surgical procedures. The 2 groups were assessed and compared in the surgical-related arterial oxygen saturation, postoperative complication rate, mortality rate, and re-intervention rate. The development of the patients' main pulmonary artery, right pulmonary artery, and left pulmonary artery was assessed by z-scores according to echocardiographic results. RESULTS: The children in the stent implantation group were younger and less weighed compared with the mBTS group (both P<0.05). Compared with the preoperative period, children in the stent implantation group had significantly higher arterial oxygen saturation [(75±17)% vs (96±3)%, P=0.026]; z-scores of pulmonary trunk [(-2.82±1.27) points vs (0.86±0.77) points, P=0.014], right pulmonary artery [(-1.88±0.59) points vs (-0.28±0.71) points, P=0.011], and left pulmonary artery [(-2.34±0.36) points vs (-1.67±0.36) points, P=0.036] were significantly increased. However, there were no significant differences in arterial oxygen saturation and pulmonary artery z-scores between pre- and post-mBTS procedures (all P>0.05). CONCLUSIONS: RVOT stent would have good surgical outcomes used in TOF patients with low weight and severe comorbidities. It also leads to an higher postoperative oxygen saturation and better promotion of pulmonary artery growth with RVOT stent compared to mBTS.

NBP Cytoprotective Effects Promoting Neuronal Differentiation in BMSCs by Inhibiting the p65/Hes1 Pathway.

Background: Bone marrow-derived mesenchymal stem cell (BMSC) transplantation has become an effective method for treating neurodegenerative diseases. Objectives: This study investigated the effect of 3-N-butylphthalide (NBP) on the neuronal differentiation of BMSCs and its potential mechanism. Methods: In this study, a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay was performed to detect cell proliferation and terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) staining was conducted to detect the apoptosis of BMSCs. Quantitative real-time polymerase chain reaction (RT-qPCR) and Western blot analysis were performed to detect the messenger RNA (mRNA) and protein expression levels, respectively. An enzyme-linked immunosorbent serologic assay assessed the levels of interleukin-1ß, tumor necrosis factor-α, and cyclic adenosine monophosphate (cAMP). Moreover, a flow cytometry assay was used to detect the proportion of active ß-tubulin III (TUJ-1) cells, and TUJ-1 expression was observed by immunofluorescence assay. Results: The results showed that a low concentration of NBP promoted the proliferation and induction of BMSC neuronal differentiation while inhibiting apoptosis, the production of inflammatory factors, and p65 expression. Compared with differentiation induction alone, combined NBP treatment increased the levels of nestin, neuron-specific enolase (NSE), TUJ-1, and microtubule-associated protein 2 (MAP2) protein, as well as the ratio of TUJ-1-positive cells and cAMP expression. Furthermore, p65 overexpression weakened the effect of NBP, and the overexpression of hairy and enhancer of split homolog-1 (HES1) reversed the effect of NBP in the induction of BMSC neuronal differentiation in vitro. Conclusions: We confirmed that NBP exhibited potential therapeutic properties in the stem cell transplantation treatment of neurodegenerative diseases by protecting cells and promoting BMSC neuronal differentiation by inhibiting the p65/HES 1 pathway.

FNIP1 abrogation promotes functional revascularization of ischemic skeletal muscle by driving macrophage recruitment.

Ischaemia of the heart and limbs attributable to compromised blood supply is a major cause of mortality and morbidity. The mechanisms of functional angiogenesis remain poorly understood, however. Here we show that FNIP1 plays a critical role in controlling skeletal muscle functional angiogenesis, a process pivotal for muscle revascularization during ischemia. Muscle FNIP1 expression is down-regulated by exercise. Genetic overexpression of FNIP1 in myofiber causes limited angiogenesis in mice, whereas its myofiber-specific ablation markedly promotes the formation of functional blood vessels. Interestingly, the increased muscle angiogenesis is independent of AMPK but due to enhanced macrophage recruitment in FNIP1-depleted muscles. Mechanistically, myofiber FNIP1 deficiency induces PGC-1α to activate chemokine gene transcription, thereby driving macrophage recruitment and muscle angiogenesis program. Furthermore, in a mouse hindlimb ischemia model of peripheral artery disease, the loss of myofiber FNIP1 significantly improved the recovery of blood flow. Thus, these results reveal a pivotal role of FNIP1 as a negative regulator of functional angiogenesis in muscle, offering insight into potential therapeutic strategies for ischemic diseases.

Antifungal Activity of Cadinane-Type Sesquiterpenes from Eupatorium adenophorum against Wood-Decaying Fungi.

The present study aimed to evaluate the antifungal activities of Eupatorium adenophorum against four strains of wood-decaying fungi, including Inonotus hispida, Inonotus obliquus, and Inonotus cuticularis. Bioguided isolation of the methanol extract of E. adenophorum by silica gel column chromatography and high-performance liquid chromatography afforded six cadinane-type sesquiterpenes. Their structures were identified by nuclear magnetic resonance and MS analyses. According to the antifungal results, the inhibition rate of the compound was between 59.85 % and 77.98 % at a concentration of 200 µg/mL. The EC50 values ranged from 74.5 to 187.4 µg/mL.

Right ventricular outflow tract stenting promotes pulmonary artery development in tetralogy of fallot.

Background: Right ventricular outflow tract (RVOT) stenting seems to be suggested as a promising treatment option and an alternative to modified Blalock-Taussig shunt (mBTS) in the initial palliation of patients with Fallot-type lesions in recent years. This study sought to assess the effect of RVOT stenting on the growth of the pulmonary artery (PA) in patients with Tetralogy of Fallot (TOF). Methods: Retrospective review analyzing 5 patients with Fallot-type congenital heart disease with small pulmonary arteries who underwent palliative with RVOT stenting and 9 patients underwent modified Blalock-Taussig shunt within 9 years period. Differential left PA (LPA) and right PA (RPA) growth was measured by Cardiovascular Computed Tomography Angiography (CTA). Results: RVOT stenting improved arterial oxygen saturation from median of 60% (interquartile range [IQR]: 37% to 79%) to 95% (87.5% to 97.5%) (p = 0.028). The LPA diameter Z-score improved from -2.843 (-3.51-2.037) to -0.78 (-2.3305-0.19) (p = 0.03), the RPA diameter Z-score improved from median -2.843 (-3.51-2.037) to -0.477 (-1.1145-0.459) (p = 0.002), the Mc Goon ratio increased from median 1 (0.8-1.105) to 1.32 (1.25-1.98) (p = 0.017). There were no procedural complications and all 5 patients have undergone final repair in the RVOT stent group. In the mBTS group, the LPA diameter Z-score improved from -1.494 (-2.242-0.6135) to -0.396 (-1.488-1.228) (p = 0.15), the RPA diameter Z-score improved from median -1.328 (-2.036-0.838) to 0.088 (-0.486-1.223) (p = 0.007), and there were 5 patients occur different complications and 4 patients was not attained the standards of final surgical repair. Conclusion: RVOT stenting, compared with mBTS, seems to better promote pulmonary artery growth, improve arterial oxygen saturations, and have less procedure complications in patients with TOF who being absolute contraindicated for primary repair due to high risks.

Disturbance of suprachiasmatic nucleus function improves cardiac repair after myocardial infarction by IGF2-mediated macrophage transition.

Suprachiasmatic nucleus (SCN) in mammals functions as the master circadian pacemaker that coordinates temporal organization of physiological processes with the environmental light/dark cycles. But the causative links between SCN and cardiovascular diseases, specifically the reparative responses after myocardial infarction (MI), remain largely unknown. In this study we disrupted mouse SCN function to investigate the role of SCN in cardiac dysfunction post-MI. Bilateral ablation of the SCN (SCNx) was generated in mice by electrical lesion; myocardial infarction was induced via ligation of the mid-left anterior descending artery (LAD); cardiac function was assessed using echocardiography. We showed that SCN ablation significantly alleviated MI-induced cardiac dysfunction and cardiac fibrosis, and promoted angiogenesis. RNA sequencing revealed differentially expressed genes in the heart of SCNx mice from D0 to D3 post-MI, which were functionally associated with the inflammatory response and cytokine-cytokine receptor interaction. Notably, the expression levels of insulin-like growth factor 2 (Igf2) in the heart and serum IGF2 concentration were significantly elevated in SCNx mice on D3 post-MI. Stimulation of murine peritoneal macrophages in vitro with serum isolated from SCNx mice on D3 post-MI accelerated the transition of anti-inflammatory macrophages, while antibody-mediated neutralization of IGF2 receptor blocked the macrophage transition toward the anti-inflammatory phenotype in vitro as well as the corresponding cardioprotective effects observed in SCNx mice post-MI. In addition, disruption of mouse SCN function by exposure to a desynchronizing condition (constant light) caused similar protective effects accompanied by elevated IGF2 expression on D3 post-MI. Finally, mice deficient in the circadian core clock genes (Ckm-cre; Bmal1f/f mice or Per1/2 double knockout) did not lead to increased serum IGF2 concentration and showed no protective roles in post-MI, suggesting that the cardioprotective effect observed in this study was mediated particularly by the SCN itself, but not by self-sustained molecular clock. Together, we demonstrate that inhibition of SCN function promotes Igf2 expression, which leads to macrophage transition and improves cardiac repair post-MI.

MicroRNA-124a regulates the differentiation of bone marrow mesenchymal stem cells into neurons.

OBJECTIVE: This study investigated the effects of microRNA-124a on the differentiation of bone marrow mesenchymal stem cells (BMSCs) and its underlying mechanism. METHODS: Flow cytometry was used for isolation and identification of BMSCs. Real-time polymerase chain reaction (RT-PCR) was used to detect gene mRNA expression. Apoptosis was detected using Annexin V-FITC/PI Apoptosis Detection Kit. Cell proliferation ability was tested using Cell Counting Kit-8 (CCK-8). The differentiation of BMSCs into neuron inducers ß-thiol ethanol or baicalin formed the basis of the study. RESULTS: ß-thiol ethanol markedly suppressed the microRNA-124a expression of BMSCs, baicalin markedly induced the microRNA-124a expression of BMSCs and ß-thiol ethanol or baicalin promoted apoptosis and reduced the growth of BMSCs. Only the microRNA-124a inhibitor did not affect apoptosis or the differentiation of BMSCs, and it increased the effects of ß-thiol ethanol or baicalin on the apoptosis of BMSCs. CONCLUSION: ß-thiol ethanol and baicalin treatment could affect microRNA-124a expression in BMSCs. We demonstrated that microRNA-124a promoted the differentiation of BMSCs into neurons.

Atrial septal defect with a rare occupying lesion in heart.

BACKGROUND: Cardiac epicardium hemangiomas are exceedingly rare; however, they can cause significant hemodynamic impairment and large pericardial effusions. On rare occasion, cardiac tumors coexist with malformations of the heart. CASE PRESENTATION: We present the case of a 10-month-old female infant with a rare cardiac surface hemangioma coexisting with malformations of the heart. It revealed an atrial septal defect (ASD) coexisting with an abnormal occupying lesion with high echogenicity. It was 35*12*9 mm in size and was found in the anterior atrioventricular junction to the posterior atrioventricular junction at the bottom of the ventricular septum by transthoracic echocardiography. We performed surgical treatment of the atrial septal defect and performed biopsy with the occupying lesion. The histopathological examination reported a benign tumor as hemangioma. As far as we know, this is the first case in which cardiac surface hemangioma was found to coexist with an atrial septal defect. CONCLUSIONS: Cardiac epicardium hemangiomas is a rare solid tumor of the heart. If the mass is impossible to resect and does not cause hemodynamic impairment, only mass biopsy is possible.

A case of rare pulmonary sequestration complicated with congenital heart disease treated by arterial embolization and atrial defect closure: A case report and review of literature.

Pulmonary sequestration with congenital heart disease is a rare congenital malformation. Herein, we report a 19-month-old toddler diagnosed with right lower pulmonary sequestration, right pulmonary artery dysplasia, right lower pulmonary venous ectopic drainage, and a right-sided heart with an atrial septal defect. The pulmonary sequestration had a rare blood supply, such as confluent arteries with the renal vessels draining into the hepatic veins. Arterial embolization and atrial defect closure were used to treat the rare congenital malformation with satisfactory results.

Strategies to improve the therapeutic effect of pluripotent stem cell-derived cardiomyocytes on myocardial infarction.

Myocardial infarction (MI) is a common cardiovascular disease caused by permanent loss of cardiomyocytes and the formation of scar tissue due to myocardial ischemia. Mammalian cardiomyocytes lose their ability to proliferate almost completely in adulthood and are unable to repair the damage caused by MI. Therefore, transplantation of exogenous cells into the injured area for treatment becomes a promising strategy. Pluripotent stem cells (PSCs) have the ability to proliferate and differentiate into various cellular populations indefinitely, and pluripotent stem cell-derived cardiomyocytes (PSC-CMs) transplanted into areas of injury can compensate for part of the injuries and are considered to be one of the most promising sources for cell replacement therapy. However, the low transplantation rate and survival rate of currently transplanted PSC-CMs limit their ability to treat MI. This article focuses on the strategies of current research for improving the therapeutic efficacy of PSC-CMs, aiming to provide some inspiration and ideas for subsequent researchers to further enhance the transplantation rate and survival rate of PSC-CMs and ultimately improve cardiac function.

Human-specific gene CT47 blocks PRMT5 degradation to lead to meiosis arrest.

Exploring the functions of human-specific genes (HSGs) is challenging due to the lack of a tractable genetic model system. Testosterone is essential for maintaining human spermatogenesis and fertility, but the underlying mechanism is unclear. Here, we identified Cancer/Testis Antigen gene family 47 (CT47) as an essential regulator of human-specific spermatogenesis by stabilizing arginine methyltransferase 5 (PRMT5). A humanized mouse model revealed that CT47 functions to arrest spermatogenesis by interacting with and regulating CT47/PRMT5 accumulation in the nucleus during the leptotene/zygotene-to-pachytene transition of meiosis. We demonstrate that testosterone induces nuclear depletion of CT47/PRMT5 and rescues leptotene-arrested spermatocyte progression in humanized testes. Loss of CT47 in human embryonic stem cells (hESCs) by CRISPR/Cas9 led to an increase in haploid cells but blocked the testosterone-induced increase in haploid cells when hESCs were differentiated into haploid spermatogenic cells. Moreover, CT47 levels were decreased in nonobstructive azoospermia. Together, these results established CT47 as a crucial regulator of human spermatogenesis by preventing meiosis initiation before the testosterone surge.

Retinoic acid inhibits the angiogenesis of human embryonic stem cell-derived endothelial cells by activating FBP1-mediated gluconeogenesis.

BACKGROUND: Endothelial cells are located in the inner lumen of blood and lymphatic vessels and exhibit the capacity to form new vessel branches from existing vessels through a process called angiogenesis. This process is energy intensive and tightly regulated. Glycolysis is the main energy source for angiogenesis. Retinoic acid (RA) is an active metabolite of vitamin A and exerts biological effects through its receptor retinoic acid receptor (RAR). In the clinic, RA is used to treat acne vulgaris and acute promyelocytic leukemia. Emerging evidence suggests that RA is involved in the formation of the vasculature; however, its effect on endothelial cell angiogenesis and metabolism is unclear. METHODS: Our study was designed to clarify the abovementioned effect with human embryonic stem cell-derived endothelial cells (hESC-ECs) employed as a cell model. RESULTS: We found that RA inhibits angiogenesis, as manifested by decreased proliferation, migration and sprouting activity. RNA sequencing revealed general suppression of glycometabolism in hESC-ECs in response to RA, consistent with the decreased glycolytic activity and glucose uptake. After screening glycometabolism-related genes, we found that fructose-1,6-bisphosphatase 1 (FBP1), a key rate-limiting enzyme in gluconeogenesis, was significantly upregulated after RA treatment. After silencing or pharmacological inhibition of FBP1 in hESC-ECs, the capacity for angiogenesis was enhanced, and the inhibitory effect of RA was reversed. ChIP-PCR demonstrated that FBP1 is a target gene of RAR. When hESC-ECs were treated with the RAR inhibitor BMS493, FBP1 expression was decreased and the effect of RA on angiogenesis was partially blocked. CONCLUSIONS: The inhibitory role of RA in glycometabolism and angiogenesis is RAR/FBP1 dependent, and FBP1 may be a novel therapeutic target for pathological angiogenesis.

Automatic Segmentation of MRI of Brain Tumor Using Deep Convolutional Network.

Computer-aided diagnosis and treatment of multimodal magnetic resonance imaging (MRI) brain tumor image segmentation has always been a hot and significant topic in the field of medical image processing. Multimodal MRI brain tumor image segmentation utilizes the characteristics of each modal in the MRI image to segment the entire tumor and tumor core area and enhanced them from normal brain tissues. However, the grayscale similarity between brain tissues in various MRI images is very immense making it difficult to deal with the segmentation of multimodal MRI brain tumor images through traditional algorithms. Therefore, we employ the deep learning method as a tool to make full use of the complementary feature information between the multimodalities and instigate the following research: (i) build a network model suitable for brain tumor segmentation tasks based on the fully convolutional neural network framework and (ii) adopting an end-to-end training method, using two-dimensional slices of MRI images as network input data. The problem of unbalanced categories in various brain tumor image data is overcome by introducing the Dice loss function into the network to calculate the network training loss; at the same time, parallel Dice loss is proposed to further improve the substructure segmentation effect. We proposed a cascaded network model based on a fully convolutional neural network to improve the tumor core area and enhance the segmentation accuracy of the tumor area and achieve good prediction results for the substructure segmentation on the BraTS 2017 data set.

[Effects of simulated insect herbivory on defense traits of Galinsoga parviflora.] / 模拟昆虫取食对牛膝菊防御特征的影响.

To understand mechanisms underlying Galinsoga parviflora invasion and its responses to simulated insect herbivory, individuals of Galinsoga parviflora were treated with different concentrations of methyl jasmonate (MeJA) before blooming. We measued plant height, abundance of leaves and inflorescences, biomass, specific leaf area, trichome density, condensed tannins, total polyphenols, and flavonoids in leaves and inflorescences. The growth and reproduction parameters of G. parviflora treated with 5 mmol·L-1 MeJA were not significantly different from those of control, higher than those of control when treated with 10 mmol·L-1 MeJA, with significant difference except plant height, and declined when treated with 20 mmol·L-1 MeJA. The trichome density of leaf upper epidermis increased and specific leaf area decreased with increasing MeJA concentration, with both being significantly different from that of control. The contents of flavonoids, total polyphenols, and condensed tannins in leaves treated with 5 mmol·L-1MeJA were not significantly different from those of control. These defensive substances in leaves and inflorescences were highest under 10 mmol·L-1MeJA treatment. The contents of flavonoids and total polyphenols in inflorescences being higher than those of leaves, while condensed tannins was opposite. The defensive substances in leaves declined under 20 mmol·L-1MeJA treatment. The results suggested that G. parviflora could use tolerance and resistance strategies comprehensively, and adopted a variety of defense strategies such as compensatory growth, physical defense, and chemical defense, which was conducive to its success in invasion.

Generation of Human Induced Pluripotent Stem Cells from Renal Epithelial Cells.

In the past decades, human induced pluripotent stem cells (iPSCs) have been generated by the ectopic expression of "Yamanaka factors" in multiple somatic cells. However, the procedure to get access to donor cells is hard or invasive in most cases. Hereon, we depict a stepwise method developed in our laboratory for the generation of iPSCs from renal epithelial cells present in urine, which is noninvasive, nonintegrating, and universal. The resulting urinary iPSCs (UiPSCs) exhibit pluripotent characteristics resemble embryonic stem cells (ESCs) and thus urine may be a favorable source for generating iPSCs.

Human retinal pigment epithelial cells.

'Human retinal pigment epithelial cells' is the first set of guidelines on human retinal pigment epithelial cells in China, jointly drafted and agreed upon by experts from the Chinese Society for Stem Cell Research. This standard specifies technical requirements, test methods, inspection rules, instructions for usage, labelling requirements, packaging requirements, storage requirements and transportation requirements and waste disposal requirements for human retinal pigment epithelial cells, which is applicable to quality control during the process of manufacturing and testing of human retinal pigment epithelial cells. It was originally released by the Chinese Society for Cell Biology on 9 January 2021. We hope that publication of these guidelines will promote institutional establishment, acceptance and execution of proper protocols and accelerate the international standardization of human retinal pigment epithelial cells for applications.

Requirements for human haematopoietic stem/progenitor cells.

'Requirements for human haematopoietic stem/progenitor cells' is the first set of guidelines on human haematopoietic stem/progenitor cells in China, jointly drafted and agreed upon by experts from the Chinese Society for Stem Cell Research. This standard specifies the technical requirements, inspection methods, inspection rules, instructions for usage, labelling requirements, packaging requirements, storage requirements and transportation requirements for human haematopoietic stem/progenitor cells, which is applicable to the quality control for human haematopoietic stem/progenitor cells. We hope that publication of these guidelines will promote institutional establishment, acceptance and execution of proper protocols, and accelerate the international standardization of human haematopoietic stem/progenitor cells for applications.

Human mesenchymal stem cells.

Mesenchymal stem cells (MSCs) have attracted great interest for cell therapy and tissue regeneration due to their self-renewal capacity, multipotency and potent immunomodulatory effects on immune cells. However, heterogeneity of MSCs has become a prominent obstacle to limit their translation into practice, as cells from different tissue sources or each individual have great differences in their transcriptomic signatures, differentiation potential and biological functions. Therefore, there is an urgent need for consensus standard for the quality control and technical specifications of MSCs. 'Human Mesenchymal Stem Cells' is the latest set of guidelines on hMSC in China, jointly drafted and agreed upon by experts from the Chinese Society for Stem Cell Research. This standard specifies the technical requirements, test methods, test regulations, instructions for use, labelling requirements, packaging requirements, storage requirements, transportation requirements and waste disposal requirements for hMSC, which is applicable to the quality control for hMSC. It was originally released by the China Society for Cell Biology on 9 January 2021. We hope that publication of these guidelines will facilitate institutional establishment, acceptance and execution of proper protocols, and accelerate the international standardization of hMSC for clinical development and therapeutic applications.

Delayed Therapy of Descending Aortic Coarctation Results in Anterior Cerebral Rupture: A Case Report.

Background: Coarctation of the aorta (CoA) is the congenital constriction or narrowing of the aortic lumen. These constrictions are primarily located in the descending aorta causing significant discrepancies in systolic blood pressures of the upper and lower extremities. Thus, a delay in diagnosis and treatment may lead to severe and adverse consequences. Case presentation: Herein, we present a 13-year-old boy with anterior cerebral rupture following a delayed diagnosis for descending CoA. Percutaneous transluminal balloon dilatation and endovascular stent implantation were urgently and successfully performed alongside cerebral clipping of the vascular aneurysm. Conclusion: An early diagnosis is crucial for CoA's successful treatment and management to prevent complications, including anterior cerebral rupture.