Post-cardiopulmonary bypass hypoxaemia in paediatric patients undergoing congenital heart disease surgery: risk factors, features, and postoperative pulmonary complications.

BACKGROUND: Hypoxemia after cardiopulmonary bypass (CPB) is the quantifiable manifestation of pulmonary dysfunction. This retrospective study was designed to investigate the risk factors for post-cardiopulmonary bypass hypoxaemia and the features of hypoxaemia and pulmonary complications in paediatric congenital heart disease surgery involving CPB. METHODS: Data including demographics, preoperative pulmonary or cardiac parameters, and intraoperative interventions were retrospectively collected from 318 paediatric patients who underwent radical surgery with CPB for congenital heart disease. Among them, the factors that were significant by univariate analysis were screened for multivariate Cox regression. The lowest ratio of arterial oxygen tension and the inspiratory oxygen fraction (PaO2/FiO2), hypoxaemia (PaO2/FiO2 ≤ 300) insult time, duration of hypoxaemia, extubation time, and pulmonary complications were also analysed postoperatively. RESULTS: The morbidity of post-cardiopulmonary bypass hypoxaemia was 48.4% (154/318). Months (6 < months ≤ 12, 12 < months ≤ 36 and 36 < months compared with 0 ≤ months ≤ 6: HR 0.582, 95% CI 0.388-0.873; HR 0.398, 95% CI 0.251-0.632; HR 0.336, 95% CI 0.197-0.574, respectively; p < 0.01), preoperative intracardiac right-to-left shunting (HR 1.729, 95% CI 1.200-2.493, p = 0.003) and intraoperative pleural cavity entry (HR 1.582, 95% CI 1.128-2.219, p = 0.008) were identified as independent risk factors for the development of post-cardiopulmonary bypass hypoxaemia. Most hypoxaemia cases (83.8%, 129/154) occurred within 2 h, and the rate of moderate hypoxaemia (100 < PaO2/FiO2 ≤ 200) was 60.4% (93/154). CONCLUSION: The morbidity of post-cardiopulmonary bypass hypoxaemia in paediatric congenital heart disease surgery was considerably high. Most hypoxaemia cases were moderate and occurred in the early period after CPB. Scrupulous management should be employed for younger infants or children with preoperative intracardiac right-to-left shunting or intraoperative pleural cavity entry.

Multiscale Shellac-Based Delivery Systems: From Macro- to Nanoscale.

Delivery systems play a crucial role in enhancing the activity of active substances; however, they require complex processing techniques and raw material design to achieve the desired properties. In this regard, raw materials that can be easily processed for different delivery systems are garnering attention. Among these raw materials, shellac, which is the only pharmaceutically used resin of animal origin, has been widely used in the development of various delivery systems owing to its pH responsiveness, biocompatibility, and degradability. Notably, shellac performs better on encapsulating hydrophobic active substances than other natural polymers, such as polysaccharides and proteins. In addition, specially designed shellac-based delivery systems can also be used for the codelivery of hydrophilic and hydrophobic active substances. Shellac is most widely used for oral administration, as shellac-based delivery systems can form a compact structure through hydrophobic interaction, protecting transported active substances from the harsh environment of the stomach to achieve targeted delivery in the small intestine or colon. In this review, the advantages of shellac in delivery systems are discussed in detail. Multiscale shellac-based delivery systems from the macroscale to nanoscale are comprehensively introduced, including matrix tablets, films, enteric coatings, hydrogels, microcapsules, microparticles (beads/spheres), nanoparticles, and nanofibers. Furthermore, the hotspots, deficiencies, and future perspectives of shellac-based delivery system development are also analyzed. We hoped this review will increase the understanding of shellac-based delivery systems and inspire their further development.

Clinicopathological features and outcomes in gastric-type of HPV-independent endocervical adenocarcinomas.

BACKGROUND: We aimed to analyze the clinicopathological features and outcomes of patients with gastric-type of HPV-independent endocervical adenocarcinoma (GAS HPVI ECA), and compare them with non-GAS HPVI ECA cases. METHODS: Thirty-eight GASs [including 17 minimal deviation adenocarcinoma (MDA), 21 non-MDA GAS] and 17 non-GAS HPVI ECAs were studied. Data of clinical features, pathological characteristics, treatment, and outcomes were evaluated. RESULTS: The median age of patients with GAS and non-GAS HPVI ECA was 46 and 48 years, respectively (p = 0.93). Compared with non-GAS HPVI ECAs, GAS had more common complains of vaginal watery discharge (p = 0.04). GAS cases were also associated with higher clinical stage (p = 0.036), more common in deeper cervical stromal invasion (p = 0.002) and lymphoavascular invasion (p = 0.044). GAS was associated with worse median progression-free survival (PFS) (p = 0.02) and median overall survival (OS) (p = 0.03) over patients with non-GAS HPVI ECAs. MDA had similar clinical and pathological features and prognosis compared with non-MDA GAS. Of note, serum CA19-9 levels were significantly higher in GAS than that in non-GAS HPVI ECA cases. CONCLUSIONS: GAS cases were more likely to have high risk pathological factors and poorer PFS and OS compared with non-GAS HPVI ECAs. Serum CA19-9 may be helpful for diagnosis and screening in patients with GAS.

Constructing an Associative Memory System Using Spiking Neural Network.

Development of computer science has led to the blooming of artificial intelligence (AI), and neural networks are the core of AI research. Although mainstream neural networks have done well in the fields of image processing and speech recognition, they do not perform well in models aimed at understanding contextual information. In our opinion, the reason for this is that the essence of building a neural network through parameter training is to fit the data to the statistical law through parameter training. Since the neural network built using this approach does not possess memory ability, it cannot reflect the relationship between data with respect to the causality. Biological memory is fundamentally different from the current mainstream digital memory in terms of the storage method. The information stored in digital memory is converted to binary code and written in separate storage units. This physical isolation destroys the correlation of information. Therefore, the information stored in digital memory does not have the recall or association functions of biological memory which can present causality. In this paper, we present the results of our preliminary effort at constructing an associative memory system based on a spiking neural network. We broke the neural network building process into two phases: the Structure Formation Phase and the Parameter Training Phase. The Structure Formation Phase applies a learning method based on Hebb's rule to provoke neurons in the memory layer growing new synapses to connect to neighbor neurons as a response to the specific input spiking sequences fed to the neural network. The aim of this phase is to train the neural network to memorize the specific input spiking sequences. During the Parameter Training Phase, STDP and reinforcement learning are employed to optimize the weight of synapses and thus to find a way to let the neural network recall the memorized specific input spiking sequences. The results show that our memory neural network could memorize different targets and could recall the images it had memorized.

Y-27632, a Rho-kinase inhibitor, attenuates myocardial ischemia-reperfusion injury in rats.

The present study aimed to evaluate the cardioprotective effects of a Rho­kinase inhibitor, Y­27632, and the underlying mechanisms. A rat model of myocardial ischemia­reperfusion (I/R) injury was generated by ligation of the coronary artery, and global ischemia of isolated rat hearts was conducted using the Langendorff system. Staining with triphenyltetrazolium chloride (TTC) and hematoxylin and eosin was performed to analyze the myocardial infarct size and histopathological alterations of the I/R­induced rat heart. In addition, coronary flow, myocardial contractility and an electrocardiogram were analyzed. The effects of Y­27632 on inflammatory cytokines and cardiac enzymes in the serum were assessed by ELISA. The expression of apoptosis­ and inflammation­associated proteins was also analyzed via western blotting. Rats in the Y­27632 group exhibited alleviated myocardial I/R injury according to TTC staining and histopathological diagnosis. Additionally, Y­27632 restored the ST segment. The data of coronary flow and myocardial contractility in isolated rat hearts indicated that Y­27632 improved heart function following I/R. The levels of inflammatory cytokines and cardiac enzymes in the serum were downregulated by Y­27632. The mitogen­activated protein kinase (MAPK) and nuclear factor (NF)­κB signaling pathways were inhibited by Y­27632. Furthermore, apoptosis­associated protein expression in rats and the isolated hearts was effectively inhibited by Y­27632. In conclusion, the findings of the present study indicated that Y­27632 attenuated myocardial injury via inhibiting the activation of the MAPK and NF­κB signaling pathways; thus, apoptosis and the inflammatory response were suppressed.

Implementing artificial neural networks through bionic construction.

It is evident through biology research that, biological neural network could be implemented through two means: by congenital heredity, or by posteriority learning. However, traditionally, artificial neural network, especially the Deep learning Neural Networks (DNNs) are implemented only through exhaustive training and learning. Fixed structure is built, and then parameters are trained through huge amount of data. In this way, there are a lot of redundancies in the implemented artificial neural network. This redundancy not only requires more effort to train the network, but also costs more computing resources when used. In this paper, we proposed a bionic way to implement artificial neural network through construction rather than training and learning. The hierarchy of the neural network is designed according to analysis of the required functionality, and then module design is carried out to form each hierarchy. We choose the Drosophila's visual neural network as a test case to verify our method's validation. The results show that the bionic artificial neural network built through our method could work as a bionic compound eye, which can achieve the detection of the object and their movement, and the results are better on some properties, compared with the Drosophila's biological compound eyes.

Changes of left ventricular structure and function after minimally invasive repair of mitral valve prolapse / 中国胸心血管外科临床杂志

@#Objective    To evaluate the changes of left ventricular structure and function by echocardiography and its grading of left ventricular diastolic function in patients with mitral valve prolapse treated by minimally invasive mitral valve repair. Methods    By retrospective analysis, 37 patients including 25 males and 12 females aged 53.49±11.02 years with mitral valve prolapse who underwent minimally invasive mitral valve repair were as an operation group, and 34 healthy persons including 19 males and 15 females aged 54.26±8.33 years matched by age and sex were selected as a control group. Ultrasound parameters of every participant were routinely collected before operation, 1 month, 3 months, 6 months and 1 year after operation, and left ventricular diastolic function was graded. The ultrasound parameters between the two groups were compared. Results    The diameters of left ventricular end systolic and diastolic phase, left atrial diameter and left ventricular volume in the operation group were significantly smaller than those before operation. The diameters of left ventricle and left atrium after operation were significantly shorter than those before operation, but they were still larger than those of the control group. The ejection fraction value decreased significantly at one month after the operation and then returned to normal level. The incidence of left ventricular diastolic dysfunction at 6 months and 1 year after operation was significantly lower than that before operation (P<0.05). Conclusion    Minimally invasive repair for patients with mitral valve prolapse can significantly improve systolic and diastolic functions of left ventricle while reconstructing left atrial and left ventricular structures.

Captopril inhibits calpain­mediated apoptosis of myocardial cells in diabetic rats and improves cardiac function.

To explore the effects of captopril on calpain­mediated apoptosis of myocardial cells and cardiac function in diabetic rats, 30 adult male Sprague­Dawley rats were randomly divided into three groups: Negative control (NC group), untreated diabetic rats (DM group) and diabetic rats treated with captopril (Cap group). Diabetes was induced by streptozotocin injection. Captopril was intragastrically administered at a daily dose of 50 mg/kg for 12 weeks; the NC and DM groups received an equivalent volume of saline. After 12 weeks of treatment, left ventricular systolic pressure (LVSP), left ventricular end­diastolic pressure (LVDEP), maximal rate of left ventricular pressure increase (+dp/dtmax), maximal rate of left ventricular pressure decrease (­dp/dtmax) and left ventricular mass index (LVMI) were measured. The levels of calpain­1, calpain­2, B­cell lymphoma (Bcl)­2, Bcl­2 associated protein X (Bax) and total caspase­3 were detected in cardiac tissue by western blot analysis. The apoptotic index (AI) was assessed with a terminal deoxynucleotidyl transferase­mediated dUTP nick­end labeling assay. The ultrastructure of cardiac tissue was determined by transmission electron microscopy. Compared with the NC group, LVDEP and LVMI were increased, whereas LVSP, +dp/dtmax and ­dp/dtmax were decreased in the DM group. In the Cap group, LVDEP and LVMI were decreased, whereas LVSP, +dp/dtmax and ­dp/dtmax were increased compared with the DM group. Bcl­2 protein expression was decreased, whereas the levels of calpain­1, calpain­2, Bax and total caspase­3 protein were increased in the DM group, compared with the NC group. Cap treatment increased Bcl­2 protein expression and decreased calpain­1, calpain­2, Bax and total caspase­3 protein expression compared with the DM group. Additionally, the AI was increased in the DM group compared with the NC group, and decreased in the Cap group compared with the DM group. Furthermore, ultrastructural examination demonstrated that myocardial cell injury was reduced in the Cap group compared with the DM group. Therefore, captopril improved myocardial structure and ventricular function, by inhibiting calpain­1 and calpain­2 activation, increasing Bcl­2 expression, reducing Bax expression and subsequently inhibiting caspase­3­dependent apoptosis.

Quercetin attenuates myocardial ischemia-reperfusion injury via downregulation of the HMGB1-TLR4-NF-κB signaling pathway.

The goal of this study was to assess the ability of quercetin (Qu) to protect against myocardial ischemia-reperfusion injury. Cardiac injury was assessed in the context of global ischemia of isolated hearts, coronary artery ligated rats, and H9C2 cells. Qu was shown to significantly inhibit inflammatory cytokine production in coronary artery occlusion-induced rats, isolated hearts, and H9C2 cells. Electrocardiographic analysis revealed a restoration of the ST segment to normal levels following treatment of Qu. Triphenyltetrazolium chloride (TTC) staining and pathological analysis showed that Qu could significantly alleviate myocardial injury in vivo. Furthermore, ex vivo analyses showed improved recovery of heart function in response to Qu, characterized by enhanced myocardial contractility and coronary flow in isolated hearts. From a mechanistic standpoint, these effects appeared to be mediated through the HMGB1-related pathway, with expression of downstream targets significantly downregulated in rats, isolated hearts, and H9C2 cells following Qu treatment. Taken together, these data demonstrate the protective effects of Qu against myocardial injury via inhibition of the HMGB1 pathway in a myocardial ischemia-reperfusion injury (I/R) model.

Hyperlipidemia induces vascular smooth muscle cell proliferation involving Wnt/ß-catenin signaling.

Hyperlipidemia has been shown to stimulate vascular smooth muscle cell (VSMC) proliferation. Wnt signaling pathway plays a critical role in embryonic development and cell proliferation. In this study, Sprague-Dawley rats fed with high-fat or normal diet for 12 weeks were sacrificed, and the thoracic aorta was harvested to determine wnt3a, ß-catenin, T-cell factor 4 (TCF4), and cyclin D1 expressions. VSMC proliferation within thoracic aorta and lipid accumulation within VSMCs were detected. Rat aortic VSMCs were cultured in serum from rats with hyperlipidemia or DKK-1; Wnt3a, ß-catenin, TCF4, and cyclin D1 expressions, and cell cycle distribution were determined. The findings demonstrated that increased number of VSMCs, lipid droplets, and vacuoles within thoracic aorta in the high-fat-fed group. Compared with controls, VSMCs from high-fat-fed rats showed higher mRNA expressions of wnt3a, ß-catenin, TCF4, and cyclin D1, as well as in VSMCs cultured with hyperlipidemic serum. After 24 h, VSMCs stimulated with hyperlipidemic serum showed significantly increased cell number and S-phase entry compared with cells exposed to normolipidemic serum. These effects were blocked by DKK-1. These results suggest that Wnt/ß-catenin signaling plays an important role in hyperlipidemia-induced VSMC proliferation.

Facile preparation of Ag-coated TiO2 nanobelts and their photocatalytic activities.

This article describes facile preparation of Ag nanoparticles coated on TiO2 nanobelts and their visible-light photocatalysis activity toward the degradation of Rhodamine B. An Ag complex was adsorbed onto the TiO2 nanobelts by impregnation of the nanobelts into an [Ag(NH3)2]NO3 aqueous solution, and subsequently the Ag precursor was reduced at room temperature by a glucose solution to form Ag nanoparticle-coated TiO2 nanobelts. The visible-light photodegradation of Rhodamine B on such nanocomposite was studied and showed much higher photocatalytic activity than commercial P-25 TiO2 nanoparticles and pure TiO2 nanobelts. Using a seeding preparation procedure through dropwise addition of fresh aqueous solution of NH2NH2 and AgNO3 alternately, larger Ag particles on TiO2 nanobelts were obtained.