Association between cesarean section and sensory integration dysfunction in preschool children: a prospective cohort study / 中国当代儿科杂志

OBJECTIVES@#To study the association between cesarean section and sensory integration dysfunction (SID) in preschool children through a prospective cohort study.@*METHODS@#Based on the multicenter mother-infant cohort established by the Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine and the International Peace Maternity and Child Health Hospital Affiliated to Shanghai Jiao Tong University School of Medicine in 2012, the sensory integration functions (three dimensions: vestibular balance, tactile defensiveness, and proprioception) of 392 preschool children were evaluated by the Chinese Children Sensory Integration Capacity Development Rating Scale in 2017. Births by cesarean section were the exposure factors, and the children born by vaginal delivery were enrolled as controls. A multivariable logistic regression analysis was used to evaluate the association of cesarean section with each dimension of SID.@*RESULTS@#The prevalence rate of SID was 21.9% (86/392) among the preschool children, and the prevalence rates of vestibular balance disorder, tactile over-responsivity, and proprioceptive disorder were 5.9% (23/392), 5.4% (21/392), and 15.1% (59/392) respectively. After adjustment for the confounding factors including maternal age at delivery and maternal educational level and child birth situation, the cesarean section group had a significant increase in the risk of proprioceptive disorder (@*CONCLUSIONS@#Cesarean section can significantly increase the risk of proprioceptive disorder in preschool children, especially in boys.

Preparation and characterization of baicalin PEG-PLGA nanomicelles and tissue distribution in rats with acute myocardial ischemia / 中草药

Objective To prepare baicalin-polyethylene glycol-poly (lactic-co-glycolic acid) copolymer (PEG-PLGA)-loaded nanomicelles, and study its in vitro drug release properties and tissue distributed in rats with acute myocardial ischemia. Methods The preparation process of baicalin PEG-PLGA nanomicelles was optimized by orthogonal test. The optimized baicalin PEG-PLGA nanomicelles were characterized by particle size, Zeta potential, and TEM electron microscopy. The in vitro release assay and tissue distribution of the acute myocardial ischemia rat model were used to evaluate this drug delivery system. Results The preferred preparation conditions for baicalin PEG-PLGA nanomicelles were a mass ratio of baicalin to PEG-PLGA at 1:10 with a rotary evaporator rotation rate of 80 r/min and a hydration temperature of 40 ℃. The optimized baicalin PEG-PLGA nanomicelle particle size was (18.5 ± 0.5) nm, the zeta potential was (-10.9 ± 0.7) mV, the drug loading was (7.9 ± 0.3)%, and the encapsulation efficiency was (86.2 ± 2.5)%. The critical micelle concentration of PEG-PLGA nanomicelles was 3.8 μg/mL by oxime assay. TEM showed that baicalin PEG-PLGA nanomicelles presented a spherical shape with uniform particle size, In vitro release test showed that baicalin PEG-PLGA nanomicelles had obvious sustained release characteristics; Tissue distribution test showed that the order of distribution of baicalin PEG-PLGA nanomicelles in normal rat organs was liver > spleen > heart > kidney > lung > brain, while the distribution of baicalin PEG-PLGA nanomicelles in acute myocardial ischemia model was liver > heart > spleen > kidney > brain. Compared with normal rats, the drug concentration in the heart of rats with acute myocardial ischemia showed a significant increase trend in all time periods, and the highest drug concentration at 120 min could reach (2 897 ± 135) ng/mL, the highest drug concentration of the heart in the normal rats was (2 411 ± 89) ng/mL, which indicated that the baicalin PEG-PLGA nanomicelles had good targeting in the acute myocardial ischemia zone. Conclusion Baicalin PEG-PLGA nanomicelles have good drug-loading properties, slow release in vitro, and can accumulate drugs in the ischemic myocardium, which has good cardiac targeting.

Effect of repeated hypoxic preconditioning on renal ischemia-reperfusion-induced hepatic dysfunction in rats / 南方医科大学学报

<p><b>OBJECTIVE</b>To explore the effect of repeated hypoxic preconditioning (RHP) on renal ischemia-reperfusion-induced hepatic dysfunction in rats and the underlying mechanism.</p><p><b>METHODS</b>A total of 120 normal SD rats were randomly divided into 4 groups (n=40), namely RHP surgical group, RHP sham-operated (RHPS) group, nonhypoxic surgical group (IRI group), and nonhypoxic sham-operated group (S group). The rats in the hypoxic groups were exposed to hypoxia in a hypoxic chamber for 5 days prior to establishment of renal ischemia-reperfusion model by resection of the right kidney and clamping the left renal hilum. Serum alanine aminotransferase (ALT), IL-17 A, TNF-a, liver superoxide dismutase (SOD) and nitric oxide (NO) were detected at 2, 8 and 24h after reperfusion, and Western blotting was used to determine the expression of p-PI3K and p-AKT;HE staining was used to observe the structural changes in the liver.</p><p><b>RESULTS</b>Compared with IRI group, RHP group showed significantly milder hepatic damage, lower ALT levels and higher NO levels at 2, 8, and 24 after reperfusion (P<0.05); TNF-a levels were lowered at 24 h (P<0.05) and SOD increased at 8 h after the reperfusion (P<0.05). Compared with S group, IRI group and RHP group showed significantly higher IL-17A levels (P<0.05) but without significant difference between the latter two groups (P>0.05). The expressions of p-PI3K and P-Al<t in RHP group were significantly higher than those in IRI group (P<0.05), especially at 8 h after reperfusion (P<0.05).</p><p><b>CONCLUSION</b>Repeated hypoxic preconditioning can attenuate hepatic injury induced by renal ischemia-reperfusion injury in rats.</p>

Reasearch progress in posterior corneal surface anterior protrusion after the excimer laser corneal refractive surgery / 中华实验眼科杂志

With the mature of techniques and development of equipments in excimer laser corneal refractive surgery,the postoperative complications are decreasing gradually.As the center of cornea become thin after laser in situ keratomileusis (LASIK)and laser subepithelial keratomileusis ( LASEK ),the strength of cornea and the intraocular pressure relatively step down,which can cause cornea anterior protrusion more or less.Because the posterior surface which is not directly affected by surgical process and healing process,so it is usually used to evaluate the protrusion of cornea.As the application of.ophthalmic anterior segment imaging and analysis system,we can get more message of cornea posterior surface.The manifestation,principle and precautionary measures of corneal posterior surface anterior protrusion after the excimer laser corneal refractive surgery were reviewed.

Changes in electrophysiological and morphological properties of neurons during the development of the visual cortex in the rat / 生理学报

To investigate the intracellular mechanism of activity-dependent synapses formation and redistribution, we studied the electrophysiological and morphological characteristics of neurons of the developing visual cortex, and observed the level of synchronism of age and changes in the properties. Whole cell patch-clamp recordings and intracellular biocytin staining were used to record postsynaptic currents (PSCs) from neurons in the visual cortex of Sprague-Dawley rats (postnatal d 4-28). The histological processing was made. There were three types of PSCs in 156 cells: silent response, monosynaptic response and polysynaptic response, during the first developmental month. Before eyes opened the number of the neurons with the silent response (57.3%) was significantly higher than that after the eyes opened (11.9%) (P<0.001). However, the incidence of polysynaptic PSCs increased from 12.4% before eyes opened to 28.9% after eyes opened (P<0.01). During postnatal week 1, all cells were classified as immature. The immature cells had very high input resistances (R(N)>1.0 G Omega), low amplitude (-0.87 mA) and short decay time (-0.98 ms). During postnatal week 4, all cells were mature with lower input resistance (R(N)<310 M Omega), larger amplitude (-66 mA), and longer decay time (-225 ms). From postnatal weeks 1 to 3, the cells had electrophysiological properties that were intermediate between the immature and mature types of cells. With biocytin intracellular staining, five types of neurons were obtained: pyramidal cells, satellite cells, basket cells, neuroglial cells and immature cells. On the basis of their electrophysiological and morphological characteristics, pyramidal cells were classified into three categories: immature, intermediate, and mature cell types. During postnatal week 1, cells were immature with very high input resistance. Morphologically immature cells had short simple dendritic arborizations which incompletely penetrated the layer where the cell body lies. From postnatal weeks 2 to 4, the cells were mature with low input resistance. They were morphologically more complex with dendritic arborizations which completely penetrated the whole layers of the visual cortex. From postnatal weeks 1 to 2, a third, intermediate cell type had electrophysiological properties that were intermediate between the immature and mature cell types. Three distinctive types of pyramidal cells in visual cortex only co-exist during postnatal weeks 1 to 2. Data show that activity-dependent synapes are formed and integrated into local neuronal networks with visual stimulation. In the critical period of visual development, the level of synchronism of age and changes in electrophysiological and morphological properties in the visual cortex is higher than that in the subcortex.