[Clinical characteristics of children with Omicron variant infection in Chengdu area, China]. / 成都地区Omicronå˜å¼‚æ ªæ„ŸæŸ“å„¿ç«¥çš„ä¸´åºŠç‰¹å¾åˆ†æž.

OBJECTIVES: To investigate the clinical characteristics of children infected with the Omicron variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in Chengdu of China. METHODS: A retrospective analysis was conducted for the clinical data of 226 children who were infected with the Omicron variant of SARS-Cov-2 and were isolated and treated in Chengdu Shelter Hospital from August 28 to September 21, 2022. According to the presence or absence of clinical symptoms, they were divided into two groups: asymptomatic group and mild symptomatic group. The two groups were compared in terms of clinical characteristics, diagnosis and treatment, and prognosis. RESULTS: Among the 226 children infected with the Omicron variant, 71 (31.4%) were asymptomatic and 155 (68.6%) had mild symptoms. Fever and cough were the most common clinical symptoms, with fever in 95 children (61.3%) and cough in 92 children (59.4%). Of all 226 children, 188 (83.2%) received coronavirus disease 2019 (COVID-19) vaccination. The time to nucleic acid clearance ranged from 6 to 26 days, with a nucleic acid clearance rate of 58.0% (131/226). There were no significant differences among different age groups in sex, early symptoms, clinical typing, nucleic acid re-positive rate, nucleic acid clearance rate, and length of hospital stay (P>0.05). There were no significant differences between the asymptomatic and mild symptomatic groups in age, sex, underlying diseases, COVID-19 vaccination, use of Lianhua Qingwen granules, nucleic acid clearance rate, nucleic acid re-positive rate, and length of hospital stay (P>0.05). CONCLUSIONS: Children infected with the Omicron variant of SARS-Cov-2 in Chengdu generally have mild clinical symptoms, mainly upper respiratory tract infection, which has little threat to the health of children of different ages, and children tend to have a good overall prognosis.

[Value of metagenomic next-generation sequencing in children with hemophagocytic syndrome with central nervous system involvement]. / å®åŸºå› ç»„äºŒä»£æµ‹åºåœ¨ä¼´æœ‰ä¸­æž¢ç¥žç»ç³»ç»Ÿå—ç´¯å„¿ç«¥å™¬è¡€ç»†èƒžç»¼åˆå¾ä¸­çš„åº”ç”¨ä»·å€¼.

OBJECTIVES: To study the value of metagenomic next-generation sequencing (mNGS) in detecting intracranial Epstein-Barr virus (EBV) infection in children with hemophagocytic syndrome (HPS) with central nervous system involvement. METHODS: A retrospective analysis was performed for the cerebrospinal fluid mNGS results of 30 HPS children with central nervous system involvement, which were compared with the results of cerebrospinal fluid EBV-DNA detection and serum EBV antibody profile. The change in serum EBV-DNA copy number after treatment was used to evaluate the efficacy of targeted therapy. RESULTS: The positive rate of EBV in cerebrospinal fluid determined by mNGS was significantly higher than that of EBV-DNA in cerebrospinal fluid (100% vs 10%, P<0.001) and had no significant difference from the positive rate of serum EBV antibody profile (100% vs 93%, P>0.05). The median number of sequences determined by mNGS was 2 400, and serum EBV-DNA copy number before treatment was moderately positively correlated with the number of EBV sequences (rs=0.693, P<0.001). The multiple linear regression analysis showed that the number of sequences determined by mNGS in cerebrospinal fluid increased with the increase in serum EBV-DNA copy number before treatment (P<0.05). CONCLUSIONS: EBV-associated HPS often results in EBV-infected viral encephalitis, and mNGS can significantly increase the detection rate of EBV in cerebrospinal fluid, which may help with clinical diagnosis.

Drug-Related Problems of Children With Chronic Diseases in a Chinese Primary Health Care Institution: A Cross-Sectional Study.

Introduction: Drug-related problems (DRPs) refer to events or circumstances involving drug therapy that actually or potentially interfere with desired health outcomes. DRPs might be severe for children with chronic diseases managed at primary health care institutions, but the relevant research is scarce. Objective: In this cross-sectional study, we aimed to explore the prevalence, types, causes, and influencing factors of DRPs in children with chronic diseases in a Chinese primary health care institution. Methods: We recruited children with chronic diseases who visited the pediatric outpatient department in a primary health care institution from July 1 to 12 October 2021. Clinical pharmacists identified DRPs through medication therapy reviews, classified the types and causes of DRPs, and distinguished the manifested DRPs that affected the outcome and potential DRPs that were going to affect the outcome. Results: A total of 188 children with chronic diseases was included, and 584 DRPs were identified in 89.89% of participants. The most common type of DRPs was "treatment effectiveness" (a manifested problem or potential problem with the effect of the pharmacotherapy; 83.56%), of which 67.29% were potential DRPs. The second common type was "treatment safety" (patient suffers or could suffer from an adverse drug event; 14.21%), of which 89.16% were potential DRPs. The most common cause of DRPs was related to the process of use (42.24%), such as "patient uses/takes less drug than prescribed or does not take the drug at all," "patient stores drug inappropriately," and "patient administers/uses the drug in a wrong way." The second common cause was related to the process of dispensing (29.83%), such as "necessary information not provided or incorrect advice provided" and "prescribed drug is not available." The third common cause was related to the process of prescribing (26.21%), such as "drug dose is too low" and "no or incomplete drug treatment despite an existing indication." The number of combined medications was an influencing factor for the frequency of DRPs (p < 0.05). Conclusion: This cross-sectional study showed that the current situation regarding DRPs among children with chronic diseases managed in the primary health care institution was serious. The types of DRPs were mainly related to treatment effectiveness, and improper usage of medications was one of the main causes of DRPs. The number of combined drugs was the influencing factor for the frequency of DRPs. In the future, pharmacists should consider formulating pharmaceutical intervention strategies for this specific group according to the characteristics of DRPs.

[Clinical Study on Early Extubation and Sequential Non-Invasive Respiratory Support for Children with Acute Respiratory Failure Receiving Invasive Mechanical Ventilation].

Objective: To explore the treatment outcome of the strategy of early extubation and then switching to non-invasive mechanical ventilation in children with acute respiratory failure, and the safety and feasibility of using the strategy to replace traditional methods. Methods: A total of 102 children, aged between 1 month to 14 years old, who had acute respiratory failure and were admitted to the pediatric ICU of West China Second University Hospital, Sichuan University between January 2019 and December 2020 were enrolled and randomly assigned to treatment group 1 (n=55) and treatment group 2 (n=47). In addition, 53 children who had the same condition in the 12 month prior to the beginning of the study were included in the control group. In the two treatment groups, the patients were extubated first, and then weaned off the ventilator. In group 1, when the patient met the invasive-non-invasive switching criteria, the tracheal tube was pulled out and non-invasive bi-level positive airway pressure (BiPAP) ventilation was used for respiratory support. In group 2, high-flow nasal cannula (HFNC) oxygen therapy was used for respiratory support. The traditional progressive weaning method was adopted for the control group (extubing and weaning were performed at the same time). The incidence of ventilator-associated pneumonia (VAP) during the period of tracheal intubation was compared and the mortality of the two groups was evaluated from the point when the patients were recruited. At the time of extubation in the treatment groups and extubation plus weaning in the control group, the pressure support levels, or PC above PEEP, intubation time, sequential time (between 2 treatment groups only), weaning failure rate, and the incidence of laryngeal edema and nasal pressure ulcer were compared. Results: The subjects of the study were predominantly infants (93 cases, 60%) and young children (31 cases, 20%). Among the 155 cases, 82 (53%) were male. There was no statistical difference in age distribution or gender among the groups. There was no significant difference in the clinical indicators among the three groups before tracheal intubation. At the time of extubation, the PC above PEEP in the two treatment groups was higher than that in the control group, and higher in group 1 than that of group 2, the difference being statistically significant (P<0.05). The intubation time of the two treatment groups was shorter than that of the control group, and shorter in group 1 than that of group 2 (P<0.05). The sequential time of group 2 was shorter than that of group 1 (P<0.05). The extubation failure rate and the incidence of VAP in the two treatment groups were lower than those in the control group, and there was no statistically significant difference between the two treatment groups. The incidence of nasal pressure ulcers in group 1 was higher than that in the other two groups (P<0.05). There was 1 death in treatment group 1, and no deaths in treatment group 2 or the control group. There was no significant difference in mortality or the incidence of laryngeal edema after extubation in the three groups. Conclusion: Early extubation and then switching to non-invasive mechanical ventilation can be well tolerated by the patients, and can be used in clinical practice as an effective weaning method for children with acute respiratory failure.

Sequential Extraction, Characterization, and Analysis of Pumpkin Polysaccharides for Their Hypoglycemic Activities and Effects on Gut Microbiota in Mice.

This study aimed to extract polysaccharides from pumpkin, characterize the structures of four of them, and evaluate their in vitro antioxidant and hypoglycemic activities. Additionally, an animal model of type 2 diabetes mellitus (T2DM) was established and used to determine their hypoglycemic and hypolipidemic effects in vivo, and the underlying mechanisms related to the regulation of gut microbiota. Water-extracted crude pumpkin polysaccharides (W-CPPs), water extraction and alcohol precipitation crude pumpkin polysaccharides (WA-CPPs), deproteinized pumpkin polysaccharides (DPPs), and refined pumpkin polysaccharides (RPPs) were sequentially extracted and purified from pumpkin powder by hot water extraction, water extraction, and alcohol precipitation, deproteinization and DEAE-52 cellulose gel column, respectively. The extraction and purification methods had significant influence on the extraction yield, physicochemical properties, and in vitro antioxidant and hypoglycemic activities. W-CCP and RPPs had a significant positive free radical-scavenging capacities and inhibitory activities on α-glucosidase and α-amylase. RPP-3 not only inhibited the uptake of glucose in Caco-2 monolayer but also promoted the excretion of glucose, while RPP-2 had no inhibitory effect. Animal experiment results showed that W-CPP treatment significantly improved the T2DM symptoms in mice, which included lowering of fasting blood glucose (FBG), reducing insulin resistance (IR), and lowering of blood lipid levels. It increased the diversity of intestinal flora and reduced the harmful flora of model mice, which included Clostridium, Thermoanaerobe, Symbiotic bacteria, Deinococcus, Vibrio haematococcus, Proteus gamma, and Corio. At the family level, W-CPP (1,200 mg/kg) treatment significantly reduced the abundance of Erysipelotrichaceae, and the Akkermanaceae of Verrucobacterium became a biomarker. Pumpkin polysaccharides reshaped the intestinal flora by reducing Erysipelotrichaceae and increasing Akkermansia abundance, thereby improving blood glucose and lipid metabolism in the T2DM mice. Our results suggest that W-CCP and RPP-3 possess strong antioxidant and hypoglycemic activities, and are potential candidates for food additives or natural medicines.

[High-risk factors for early failure of high-flow nasal cannula oxygen therapy in children].

OBJECTIVE: To determine the high-risk factors for early failure of high-flow nasal cannula (HFNC) oxygen therapy in children with acute respiratory insufficiency (ARI). METHODS: The clinical data of 123 children with ARI were reviewed who received HFNC oxygen therapy in the pediatric intensive care unit from January to June, 2018. The children who did not require an upgrade of respiratory support during hospitalization and were successfully weaned from HFNC were classified as HFNC success group (69 cases). Of the remaining children (54 cases) who required an upgrade of their respiratory support during hospitalization, those that needed to upgrade their respiratory support within 48 hours of receiving HFNC were classified as early HFNC failure group (46 cases). Risk factors for early failure of HFNC were determined using multivariate logistic regression analysis. RESULTS: The incidence rates of shock, sepsis, intracranial hypertension syndrome, and multiple organ dysfunction syndrome were significantly higher in the early HFNC failure group than in the HFNC success group (P<0.05). Before implementation of respiratory support, the early HFNC failure group had significantly lower Glasgow coma score, pH value, and oxygenation index and significantly higher Pediatric Risk of Mortality (PRISM) score and PaCO2/PaO2 ratio than the HFNC success group (P<0.05). Multivariate logistic regression analysis showed that PRISM score >4.5 and PaCO2/PaO2 ratio >0.64 were independent risk factors for early HFNC failure (OR=5.535 and 9.089 respectively; P<0.05). CONCLUSIONS: Pediatric ARI patients with PRISM score >4.5 or PaCO2/PaO2 ratio >0.64 have relatively high risk of early HFNC failure.

Bursopentin (BP5) induces G1 phase cell cycle arrest and endoplasmic reticulum stress/mitochondria-mediated caspase-dependent apoptosis in human colon cancer HCT116 cells.

BACKGROUND: Bursopentin (BP5) is a multifunctional pentapeptide found in the chicken bursa of Fabricius. Recent study indicated that BP5 significantly stimulates expression of p53 protein in colon cancer HCT116 cells. However, the effects and underlying mechanisms of BP5 on HCT116 cell proliferation remain largely unclear. METHODS: Analyses of cell viability, cell cycle arrest as well as apoptosis were performed to study the actions of BP5 on HCT116 cells. Western blot analyse was assayed to measure the cell cycle-related and apoptosis-related proteins. Specific siRNAs targeting IRE1, ATF-6, and PERK were used for IRE1, ATF-6, and PERK knockdown, respectively. Cellular reactive oxygen species (ROS) were detected using a H2DCF-DA green fluorescence probe. Cytosolic free Ca2+ concentrations and mitochondrial membrane potential (ΔΨm) were measured using Fluo-3 AM and JC-1 stains, respectively. RESULTS: BP5 possessed strong inhibitory effects on the cell growth and induced apoptosis in HCT116 cells. Mechanistically, BP5 arrested the cell cycle at G1 phase by increasing p53 and p21 expression and decreasing cyclin E1-CDK2 complex expression. BP5 treatment dramatically activated the endoplasmic reticulum (ER) stress-mediated apoptotic pathway, as revealed by the significantly enhanced expression of unfolded protein response (UPR) sensors (IRE1α, ATF6, PERK) as well as downstream signaling molecules (XBP-1s, eIF2α, ATF4 and CHOP), and by the significantly altered the BP5-induced phenotypic changes in IRE1, ATF6, and PERK knockdown cells. Additionally, BP5-induced ER stress was accompanied by the accumulation of cytosolic free Ca2+ and intracellular ROS. Furthermore, BP5 treatment resulted in the increase of Bax expression, the decrease of Bcl-2 expression and the reduction of ΔΨm, subsequently causing a release of cytochrome c from the mitochondria into the cytoplasm and finally enhancing the activities of caspase-9 and -3. In addition, z-VAD-fmk, a pan-caspase inhibitor, markedly rescued BP5-induced cell viability reduction and reduced BP5-induced apoptosis. CONCLUSIONS: Our present results suggest that BP5 has an anticancer capacity to arrest cell cycle at G1 phase and to trigger ER stress/mitochondria-mediated caspase-dependent apoptosis in HCT116 cells. Therefore, our findings provide insight into further investigations of the anticancer activities of BP5.

Controllable reduction of graphene oxide by electron-beam irradiation.

The oxygen content of graphene oxide (GO) is directly related to its physical and chemical properties, such as hydrophilicity, suspension stability, adsorption, and ion-sieving ability of GO membranes. Here, a series of reduced GO (rGO) with C/O atomic ratios from 1.6 to 4.8 were prepared conveniently by electron-beam irradiation (EBI) with irradiation-dose control. Moreover, a single oxygen-containing group, i.e., epoxy or carbonyl, could be retained mainly in the rGO. The interlayer spacing of rGO could be changed from 9.6 Å to 7.4 Å through control of the oxygen content. The prepared rGO exhibited an excellent adsorption effect on Pb(ii) ions, and the max adsorption capacity reached 194.76 mg g-1 for rGO with a low irradiation dose (5 kGy), which showed that the ratio of oxygen-containing groups is important for improving the adsorption of rGO in aqueous solution. These results indicated that highly efficient, environmentally friendly, and advanced EBI technology has good potential prospects for use in the large-scale production of rGO with precise control of the oxygen content.

Comparison of deep or moderate neuromuscular blockade for thoracoscopic lobectomy: a randomized controlled trial.

BACKGROUND: Laparoscopic surgery typically requires deep neuromuscular blockade (NMB), but whether deep or moderate NMB is superior for thoracoscopic surgery remains controversial. METHODS: Patients scheduled for thoracoscopic lobectomy under intravenous anesthesia were randomly assigned to receive moderate [train of four (TOF) 1-2] or deep NMB [TOF 0, post-tetanic count (PTC) 1-5]. Depth of anesthesia was controlled at a Narcotrend rating of 30 ± 5 in both groups. The primary outcome was the need to use an additional muscle relaxant (cisatracurium) during surgery. Secondary outcomes included surgeon satisfaction, recovery time of each stage after drug withdrawal [time from withdrawal until TOF recovery to 20% (antagonists administration), 25, 75, 90, 100%], blood gas data, VAS pain grade after extubation, the time it takes for patients to begin walking after surgery, postoperative complications and hospitalization time. Results were analyzed on an intention-to-treat basis. RESULTS: Thirty patients were enrolled per arm, and all but one patient in each arm was included in the final analysis. Among patients undergoing moderate NMB, surgeons applied additional cisatracurium in 8 patients because of body movement and 5 because of coughing (13/29, 44.8%). Additional cisatracurium was not applied to any of the patients undergoing deep NMB (p < 0.001). Surgeons reported significantly higher satisfaction for patients undergoing deep NMB (p < 0.001, Wilcoxon rank sum test). The mean difference between the two groups in the time from withdrawal until TOF recovery of 25% or 90% was 10 min (p < 0.001). The two groups were similar in other recovery data, blood gas analysis, VAS pain grade, days for beginning to walk and mean hospitalization time. CONCLUSIONS: Deep NMB can reduce the use of additional muscle relaxant and increase surgeon satisfaction during thoracoscopic lobectomy. TRIAL REGISTRATION: Chinese Clinical Trial Registry, ChiCTR-IOR-15007117 , 22 September 2015.

Rutin attenuates isoflurane-induced neuroapoptosis via modulating JNK and p38 MAPK pathways in the hippocampi of neonatal rats.

An increasing number of infants and children undergo surgery and are exposed to anesthesia as a part of medical care each year. Isoflurane is a commonly used anesthetic in the pediatric population. However, previous studies have reported widespread isoflurane-induced neuroapoptosis and cognitive impairments in neonatal animal models, raising concerns over the administration of isoflurane in the pediatric population. The current study investigated the effects of rutin, a flavonoid, on isoflurane-induced neuroapoptosis in a neonatal rodent model. Groups of neonatal rat pups were administered rutin at doses of 10, 20 or 40 mg/kg body weight from postnatal day 1 (P1) to P15. On P7, pups were exposed to 0.75% isoflurane for 6 h. Rat pups in the control groups did not receive rutin, and did not receive anesthesia in one group. Neuroapoptosis following isoflurane exposure was determined by TUNEL assay. The expression levels of cleaved caspase-3, apoptotic pathway proteins [Bcl2-associated agonist of cell death (Bad), phospho-Bad, Bax, B-cell lymphoma 2 (Bcl-2) and Bcl-xL and mitogen-activated protein kinases (MAPK)] signalling pathway proteins [c-Jun N-terminal kinase (JNK), phospho-JNK, extracellular-signal-regulated kinase 1/2 (ERK1/2), phosphoERK1/2, p38, phospho-p38 and phospho-c-Jun], were determined by western blot analysis. The Morris water maze test was used to assess the learning and memory of pups on P30 and P31. The present study found that rutin at the tested doses of 10, 20 and 40 mg significantly reduced (P<0.05) the isoflurane-induced elevation in apoptotic cell count. The expression levels of caspase-3, Bad, Bax and MAPK proteins, which were increased following isoflurane treatment, were rescued by rutin treatment. Furthermore, rutin prevented the increase in Bcl-xL, Bcl-2 and phospho-Bad expression following isoflurane treatment, and enhanced the memory of the rats. Rutin provided neuroprotection against isoflurane-induced neuronal apoptosis and improved the learning and memory of rats by effectively regulating the expression levels of proteins in the MAPK pathway.

[Role of c-Jun N-terminal kinase-mediated FOXO3a nuclear translocation in neuronal apoptosis in neonatal rats with hypoxic-ischemic brain damage].

OBJECTIVE: To explore the mechanisms of neuroprotective effects of c-Jun N-terminal kinase (JNK)/FOXO3a transcription factor signaling pathway inhibition on hypoxic-ischemic neuronal apoptosis in neonatal rats with hypoxic-ischemic brain damage (HIBD). METHODS: Sixty-four 7-day-old Sprague-Dawley rats were divided into four groups: hypoxia-ischemia (HI), sham-operated, JNK specific inhibitor AS601245-treated, and DMSO vehicle. Rats' cerebral cortexes were collected at 24 hours after HI. Western blot was used to detect the protein expression of JNK, p-JNK, FOXO3a, nuclear and cytoplasmic FOXO3a, Bim, and CC3. TUNEL staining was used to detect the apoptotic cells. RESULTS: Compared with the sham-operated group, p-JNK protein increased (P<0.01), nuclear protein of FOXO3a increased (P<0.01), cytoplasmic protein decreased (P<0.01), and pro-apoptotic proteins Bim and CC3 increased 24 hours after HI (P<0.01). Compared with the HI and DMSO vehicle groups, p-JNK protein was reduced (P<0.01), nuclear protein of FOXO3a was also reduced (P<0.01), cytoplasmic protein increased (P<0.01), and Bim and CC3 proteins decreased (P<0.01) in the AS601245-treated group 24 hours after HI. TUNEL positive cells were reduced in the AS601245-treated rats compared with the HI and DMSO vehicle groups 24 hours after HI (P<0.01). CONCLUSIONS: JNK activity increases in the neonatal rat brain with HI damage. JNK activity inhibition can inhibit FOXO3a translocation from cytoplasm to nucleus and downregulate the levels of pro-apoptotic proteins Bim and CC3, leading to the reduction of neuronal apoptosis.

[Role of STAT3 signaling pathway in hypoxic-ischemic brain damage of neonatal rats].

OBJECTIVE: To study the role and mechanisms of STAT3 signaling pathway in hypoxic-ischemic brain damage (HIBD) of neonatal rats. METHODS: Eighty 7-day-old Sprague-Dawley rats were randomly divided into two groups: HI and sham-operated (n=40 each). The rats in the HI group were subjected to right carotid artery ligation and subsequent hypoxia exposure (8% O2) for 2.5 hours, and the rats in the sham-operated group underwent the right carotid artery dissection without subsequent ligation or hypoxia treatment. Brain tissue samples were collected at 4, 6, 8, 12 and 24 hours after operation and hypoxic exposure. Immunohistochemistry and Western blot were used to detect the expression of STAT3, phosphorylated STAT3 (p-STAT3) and vascular endothelial growth factor (VEGF) proteins. TUNEL staining was used to detect apoptotic cells. RESULTS: No significant difference in STAT3 expression was observed at all time points between the HI and sham-operated groups (P>0.05). Compared with the sham-operated group, the expression of p-STAT3 protein in the HI group was significantly upregulated at 4, 6, 8, 12 hours after operation and hypoxic exposure, and peaked at 6 hours (P<0.01). The VEGF expression in the HI group was higher than that in the sham-operated group at all time points, which peaked at 8 hours (P<0.05). TUNEL staining showed that the apoptotic cells increased significantly in a time-dependent manner compared with the sham-operated group (P<0.01). CONCLUSIONS: HI may lead to phosphorylation of STAT3 which probably induces the VEGF expression in the brain of neonatal rats. The activated STAT3 signaling pathway may be involved in the apoptosis regulation of nerve cells, and related to apoptosis inhibition of nerve cells.

[Changes of phosphatase PTEN in neuronal apoptosis in neonate rats with hypoxic-ischemic brain damage].

OBJECTIVE: To examine the changes in expression of phosphatase and tensin homolog deleted on chromosome ten (PTEN) protein, p-PTEN protein and Bim (Bcl-2 interacting mediator of cell death) mRNA in the cortex of neonate rat brains with hypoxic-ischemic brain damage (HIBD) and to explore the mechanisms of neuroprotective effects of PTEN inhibition. METHODS: One hundred and twenty-eight neonate (10 days) SD rats were divided into four groups: hypoxia-ischemia (HI), sham control (Sham), bisperoxovanadium (bpv), and normal saline (NS) group. Rats in the HI group had their right common carotid arteries (CCA) exposed and ligated, and were then exposed to hypoxia in a chamber filled with 8% oxygen (balanced with nitrogen) for 2.5 h. Rats in the sham control group had their right CCA surgically exposed without ligation and exposure to hypoxia. Rats in the bpv treated group received intraperitoneal injections of bpv, 30 min before HI was induced. Instead of bpv, rats in the NS-treated group received intraperitoneal injections of NS. Cerebral cortex samples of the rats were collected 0.5 h and 24 h after hypoxia. Western blot was used to detect the protein expression of PTEN, p-PTEN and Bim. Real-Time PCR was used to detect the level of Bim mRNA. TUNEL staining was used to detect apoptotic cells. RESULTS: No significant changes of PTEN protein were observed in the rats exposed to HI. However, p-PTEN protein decreased in the rats exposed to HI (0.5 h and 24 h) compared with those exposed to sham surgery (P < 0.01). Compared with the sham controls, Bim mRNA and protein increased in the rats exposed to HI (0.5 h, P < 0.01) and then returned to the baseline level 24 h after HI. No significant changes of PTEN protein were observed in the bpv-treated rats. However, p-PTEN protein increased and Bim mRNA and protein decreased in the bpv-treated rats (0.5 h and 24 h, P < 0.01) compared with those in the HI group and NS-treated group. TUNEL positive cells also reduced in the bpv-treated rats (24 h, P < 0.01) compared with those in the HI group and NS-treated group. CONCLUSION: PTEN activities increase in the brains of neonate rats with hypoxic-ischemic brain damage. PTEN activity inhibition can decrease the level of pro-apoptotic protein Bim mRNA, leading to reduction of neuronal apoptosis.

[Effect of integrin ß8 on TGF-ß1 activation in astrocytes with oxygen glucose deprivation].

OBJECTIVE: To study the effect of ß8 expression on transforming growth factor ß1(TGF-ß1) activation in astrocytes with oxygen glucose deprivation (OGD). METHODS: Astrocytes were cultured and then subjected to OGD to generate hypoxia-ischemia (HI) model in vitro. Immunocytochemistry was used to detect the expression and distribution of ß8 in nomoxia cultured cells. ß8 protein expression was quantified by Western blot at 12 hours, 1 day and 2 days after OGD. Astrocytes and luciferase reporter cells (TMLC) were co-cultured. ß8 RNA interference system was established to specifically inhibit ß8 expression in cultured astrocytes. TGF-ß1 activation was then detected in the co-culture system. RESULTS: ß8 was mainly located in the cytoplasm and neurites of astrocytes. OGD resulted in increase of ß8 protein expression at 12 hours after reoxygenation in astrocytes, which was peaked at 1 day after reoxygenation. TGF-ß1 activation was in accordance with ß8 expression in astrocyte-TMLC co-culture system after reoxygenation. After the inhibition of ß8, TGF-ß1 activation was significantly reduced in all time points. CONCLUSIONS: The highly expressed ß8 plays important roles in the regulation of TGF-ß1 activation in neonatal rats with hypoxic-ischemic brain damage.

[Role of the FOXO3a transcription factor in neuronal apoptosis in neonatal rats with hypoxic-ischemic brain damage].

OBJECTIVE: To explore the role and mechanisms of FOXO3a nuclear translocation in neuronal apoptosis after hypoxia-ischemia (HI). METHODS: One hundred and sixty 10-day-old Sprague-Dawly rats were randomly divided into two groups: HI and sham-operated. The right common carotid artery was ligated followed by hypoxia exposure for 2.5 hours in the HI group. The sham-operated group rats were not subjected to carotid artery ligation or hypoxia treatment. Rat cerebral cortex was collected at 0.5, 2, 4, 8 and 24 hours after hypoxia. Western blot was used to detect expression of total FOXO3a protein, pnuclear and cytoplasmic FOXO3a and Bim. TUNEL staining was used to detect apoptotic cells. RESULTS: The nuclear protein of FOXO3a obviously increased from 0.5 to 24 hours after HI in a time-dependent manner compared with the sham-operated group (P<0.01). On the contrary, cytoplasmic protein evidently decreased from 0.5 to 24 hours in the HI group compared with the sham-operated group (P<0.01). Bim protein increased from 0.5 hour, peaked at 2 hours, started to decline at 4 hours (P<0.01), and returned to baseline level at 8 and 24 hours after HI in the HI group compared with the sham-operated group. TUNEL positive cells started to express at 4 hours, and peaked at 24 hours after HI (P<0.01). However, TUNEL positive cells were rarely found in the sham-operated group. CONCLUSIONS: HI induces FOXO3a translocation from cytoplasm to nucleus, and enhances protein expression of its target gene Bim in the neonatal rat brain. The upregulation of Bim expression might be related to neuronal apoptosis.

The suppressive effects of Bursopentine (BP5) on oxidative stress and NF-ĸB activation in lipopolysaccharide-activated murine peritoneal macrophages.

BACKGROUND/AIM: Bursopentine (BP5) is a novel thiol-containing pentapeptide isolated from chicken bursa of Fabricius, and is reported to exert immunomodulatory effects on B and T lymphocytes. It has been found that some thiol compounds, such as glutathione (GSH) and N-acetylcysteine (NAC) protect living cells from oxidative stress. This led us to investigate whether BP5 had any ability to protect macrophages from oxidative stress as well as any mechanism that might underlie this process. METHODS: Murine peritoneal macrophages activated by lipopolysaccharide (LPS) (2 µg/ml) were treated with single bouts (0, 25, 50, and 100 µM) of BP5. RESULTS: BP5 potently suppressed the markers for oxidative stress, including nitric oxide (NO), reactive oxygen species (ROS), lipid peroxidation, and protein oxidation. It also decreased the expression and activity of inducible nitric oxide synthase (iNOS) and promoted a protective antioxidant state by elevating GSH content and by activating the expression and activity of certain key antioxidant and redox enzymes, including glutathione peroxidase (GPx), glutathione reductase (GR), superoxide dismutase (SOD) and catalase (CAT). This suppressive effect on oxidative stress was accompanied by down-regulated expression and activity of nuclear factor kappa B (NF-κB). CONCLUSION: These findings demonstrate that BP5 can protect LPS-activated murine peritoneal macrophages from oxidative stress. BP5 may have applications as an anti-oxidative stress reagent.

[The studies of GLUT1 expression and neuron apoptosis in neonatal hypoxic-ischemia brain damage rat model].

OBJECTIVE: To investigate the relationship between the expression of glucose transporter protein 1 and the apoptosis of neuron during hypoxic-ischemia brain damage in neonatal rats. METHODS: Total 120 10-day old SD rats were divided into normal group, sham control group and hypoxic-ischemia (HI) group. In HI group, hypoxic-ischemia brain damage (HIBD) were generated according to Rice-Vannucci method, brain tissues were harvested at 2, 8, 24, 48 and 72 h after HI. The brain samples were also collected at the same time points in normal group and sham control group. The pathological changes was observed by hematoxylin-eosin (HE) staining, the mRNA expression of glucose transporter 1 (GLUT1) was detected by reverse transcriptase-polymerase chain reaction (RT-PCR), the protein expressions of GLUT1 and cleaved caspase-3 (CC3) were detected by immunohistochemistry, the apoptosis of neuron was measured by TdT-mediated dUTP-biotin nick end labeling (TUNEL) staining. RESULTS: HE staining showed that the degree of brain cell damage increased with time after HI, the loss of neuronal cells peaked at 48 h, while the cells in control group apperanted in an orderly and normal morphology. The mRNA and protein expressions of GLUT1 were increased after HI, which began to increase at 2 h, and reach the peak at 24 h. and the expression levels at each time points were statistically higher (P< 0.01) than those in control group. CC3 protein expression also began to increase at 2 h, peaked at 48 h after HI, which was higher than that of control group (P<0.01). The number of positive cells was significantly increased after HI,with a peak at 48 h. CONCLUSION: The mRNA and protein expression of GLUT1 in brain tissue increased significantly after hypoxic-ischemia, and the peak time was earlier than that of CC3 protein and cellular apoptosis. This suggests that GLUT1 expression upregulation may be a certain degree of inhibition on neuronal apoptosis.

[Roles of glutamate receptor 2 and cellular free calcium in the pathogenesis of periventricular leukomalacia].

OBJECTIVE: To study the expression of the AMPA receptor subunit glutamate receptor 2 (GluR2) and the cellular free calcium concentration in the white matter of neonatal rats with periventricular leukomalacia (PVL) and their roles in the pathogenesis of PVL. METHODS: A PVL model was prepared by unilateral carotid artery ligation (UCL) followed by exposure to 6% oxygen for 4 hrs in 2-day-old rats. The neonatal rats performed a sham operation, without hypoxia-ischemia (HI), were used as the control group. At 12, 24, 48 and 72 hrs of HI, the expressions of GluR2 mRNA and protein in the white matter were detected using real time quantitative PCR and Western blot respectively. Spectrophotofluorimetry and Fura 2/AM were used to detect the cellular free calcium concentration. RESULTS: The expressions of GluR2 mRNA and protein in the white matter were significantly reduced in the PVL group at 24 hrs of HI, and remained at lower expressions until 72 hrs of HI compared with the control group (P < 0.05). The cellular free calcium concentrations increased significantly in the PVL group at 12 hrs of HI, and remained at higher levels until 72 hrs of HI compared with the control group (P < 0.05). CONCLUSIONS: The expressions of GluR2 mRNA and protein in the white matter decreased whereas the cellular free calcium concentration increased in neonatal rats with PVL. The decreased expression of GluR2 might lead to the overloading of cellular calcium in the white matter, which may cause neuronal damage and death.

[Expression of P75NTR protein and RhoA mRNA in the brain of neonatal rats with white matter damage].

OBJECTIVE: Recent studies have indicated that the signal pathway of NgR-P75NTR- RhoA plays a key role in nerve injury and remodeling, but its exact mechanism and the role of the downstream molecule RhoA regulated by P75NTR remain unclear in hypoxia-ischemia (HI) neonatal animals. The present study was designed to assess the expression of P75NTR protein and RhoA mRNA in neonatal white matter and to investigate their relationship in newborn rats with white matter damage (WMD). METHODS: The rat WMD model was established by the ligation of right common carotid artery, followed by 6% hypoxia exposure for 4 hrs. The control group was sham-operated, without HI treatment. The histological changes of brain tissue were observed under light and electron microscopes. Expression of P75NTR protein and RhoA mRNA in the brain white matter after 12, 24, 48 and 72 hrs and 7 days of HI were detected by RT-PCR and immunohistochemistry, respectively. RESULTS: Periventricular white matter damage was observed by 48 hrs of HI. Expression of P75NTR protein increased in the striatum and callosum zones at 12 hrs, peaked at 48 hrs, and remained at a higher level than control until 72 hrs of HI in the WMD group (P < 0.01). After 7 days of HI expression of P75NTR protein was no longer statistically different from controls. The RhoA mRNA was higher in the WMD group for the first 72 hrs and then declined to control values. CONCLUSIONS: Increased P75NTR protein might mediate apoptosis of nerve cells and inhibit the regeneration of neuron axons. The subsequent decline back to control value may be correlated with the aggregation of necrosis of nerve cells after HI. The patterns of RhoA mRNA expression were consistent with those of P75NTR protein, suggesting that the increased P75NTR level may promote RhoA mRNA expression.