C8-ceramide modulates microglia BDNF expression to alleviate postoperative cognition dysfunction via PKCδ/NF-κB signaling pathway.

Postoperative cognitive dysfunction (POCD) is a kind of serious postoperative complication in surgery with general anesthesia and it may affect patients' normal lives. Activated microglia are thought to be one of the key factors in the regulation of POCD process. Once activated, resident microglia change their phenotype and secrete kinds of cytokines to regulate inflammatory response in tissues. Among these secretory factors, brain-derived neurotrophic factor (BDNF) is considered to be able to inhibit inflammation response and protect nervous system. Therefore, the enhancement of BDNF expression derived from resident microglia is suggested to be potential treatment for POCD. In our study, we focused on the role of C8-ceramide (a kind of interventional drug) and assessed its regulatory effect on improving the expression of BDNF secreted from microglia to treat POCD. According to the results of our study, we observed that C8-ceramide stimulated primary microglia to up-regulate the expression of BDNF mRNA after being treated with lipopolysaccharide (LPS) in vitro. We proved that C8-ceramide had ability to effectively improve POCD of mice after being accepted carotid artery exposure and their abnormal behavior recovered better than that of mice from the surgery group. Furthermore, we also demonstrated that C8-ceramide enhanced the cognitive function of mice via the PKCδ/NF-κB signaling pathway. In general, our study has confirmed a potential molecular mechanism that led to the occurrence of POCD caused by surgery and provided a new clinical strategy to treat POCD.

Synthesis of cBN-hBN-SiCw Nanocomposite with Superior Hardness, Strength, and Toughness.

Nanocomposites with one-dimensional (1D) and two-dimensional (2D) phases can demonstrate superior hardness, fracture toughness, and flexural strength. Cubic boron nitride-hexagonal boron nitride-silicon carbide whiskers (cBN-hBN-SiCw) nanocomposites with the simultaneous containing 1D SiCw and 2D hBN phases were successfully fabricated via the high-pressure sintering of a mixture of SiCw and cBN nanopowders. The hBN was generated in situ via the limited phase transition from cBN to hBN. Nanocomposites with 25 wt.% SiCw exhibited optimal comprehensive mechanical properties with Vickers hardness of 36.5 GPa, fracture toughness of 6.2 MPa·m1/2, and flexural strength of 687.4 MPa. Higher SiCw contents did not significantly affect the flexural strength but clearly decreased the hardness and toughness. The main toughening mechanism is believed to be a combination of hBN inter-layer sliding, SiCw pull-out, crack deflection, and crack bridging.

Dexmedetomidine post-conditioning attenuates cerebral ischemia following asphyxia cardiac arrest through down-regulation of apoptosis and neuroinflammation in rats.

BACKGROUND: Neuroprotection strategies after cardiac arrest (CA)/cardiopulmonary resuscitation (CPR) remain key areas of basic and clinical research. This study was designed to investigate the neuroprotective effects of dexmedetomidine following resuscitation and potential mechanisms. METHODS: Anesthetized rats underwent 6-min asphyxia-based cardiac arrest and resuscitation, after which the experimental group received a single intravenous dose of dexmedetomidine (25 µg/kg). Neurological outcomes and ataxia were assessed after the return of spontaneous circulation. The serum levels and brain expression of inflammation markers was examined, and apoptotic cells were quantified by TUNEL staining. RESULTS: Neuroprotection was enhanced by dexmedetomidine post-conditioning after the return of spontaneous circulation. This enhancement was characterized by the promotion of neurological function scores and coordination. In addition, dexmedetomidine post-conditioning attenuated the serum levels of the pro-inflammatory cytokine tumor necrosis factor (TNF)-α at 2 h, as well as interleukin IL-1ß at 2, 24, and 48 h. TUNEL staining showed that the number of apoptotic cells in the dexmedetomidine post-conditioning group was significantly reduced compared with the control group. Further western blot analysis indicated that dexmedetomidine markedly reduced the levels of caspase-3 and nuclear factor-kappa B (NF-κB) in the brain. CONCLUSIONS: Dexmedetomidine post-conditioning had a neuroprotective effect against cerebral injury following asphyxia-induced cardiac arrest. The mechanism was associated with the downregulation of apoptosis and neuroinflammation.

[Effects of edaravone on glial fibrillary acidic protein and interleukin-lß expression and neuronal apoptosis in juvenile rat hippocampus after status convulsion].

OBJECTIVE: To study the effects of edaravone on glial fibrillary acidic protein (GFAP) and interleukin-1ß (IL-lß) expression and neuronal apoptosis in the juvenile rat hippocampus after status convulsion (SC). METHODS: One hundred and ninety-five juvenile male Sprague-Dawley (SD) rats were randomly divided into 3 groups: normal saline control and SC with and without edaravone treatment. Each of the 3 groups was further subdivided into subgroups sacrificed at 4, 12, 24, 48 and 72 hrs after SC (n=15). The SC model was prepared using lithium-pilocarpine. The expression of GFAP and IL-lß protein was detected with immunohistochemistry methods. The neuronal apoptosis was observed by TdT-mediated dUTP nick end labeling (TUNEL). The hippocampal GFAP mRNA expression was detected by RT-PCR. RESULTS: The value of IOD of GFAP and IL-lß positive cells measured by immunohistochemistry in the untreated SC group increased compared with the control group. Expression of GFAP and IL-lß protein was significantly reduced in the edaravone treated SC group compared with the untreated SC group. RT-PCR showed the expression trend of GFAP mRNA was similar to that of protein. The TUNEL positive cells in the hippocampus CA1 in the untreated SC group increased significantly 12 hrs after SC and reached a peak at 48 hrs compared with the control group. The intervention with edaravone decreased significantly TUNEL positive cells between 12-48 hrs after SC, but the number of TUNEL positive cells in the intervention group remained significantly greater than in the control group. CONCLUSIONS: The expression of GFAP and IL-lß in the hippocampus increases after SC in rats. Edaravone may decrease the expression of GFAP and IL-1ß and reduce the number of neuronal apoptosis. These results suggest that edaravone may have protective effects against brain damage caused by SC.

[Effects of edaravone on the expression of GRP78, Caspase-12, and neuron apoptosis in juvenile rat hippocampus after status convulsive].

OBJECTIVE: To observe the expression of GRP78 (glucose regulated protein, GRP78), Caspase-12 and the change of neuron apoptosis in the juvenile rat hippocampus after status convulsive (SC), and to explore the effect of edaravone on them. METHODS: One hundred and ninety-five juvenile male Sprague-Dawley (SD) rats were randomly divided into normal saline control group (NS group), status convulsive group (SC group) and edaravone treatment group (ED group). Each group was further divided into five subgroups in different executed time points after SC. The rats in status convulsive group were kindled into epilepsy by lithium-pilocarpine method. Expression of GRP78 mRNA and caspase-12 mRNA was detected with reverse transcription-polymerase chain reaction (RT-PCR) method. Expressions of GRP78 and caspase-12 protein were detected with immunohistochemical methods. The neuron apoptosis was observed by TdT-mediated dUTP nick end labeling (TUNEL). RESULTS: (1) Measured by immunohistochemistry the value of OD of GRP78 (0.1480 ± 0.0164, 0.1682 ± 0.0114, and 0.1540 ± 0.0102, respectively, 12 h - 48 h points) and caspase-12 (0.1325 ± 0.0165, 0.1794 ± 0.0213, 0.1525 ± 0.0423, and 0.1309 ± 0.0199, respectively, 12 h-72 h points) positive cells in the SC group increased, there was a significant difference compared with NS group (GRP78: 0.1214 ± 0.0147, 0.1272 ± 0.0177, and 0.1260 ± 0.0157, respectively, 12 h-72 h points. Caspase-12: 0.1050 ± 0.0121, 0.1041 ± 0.0151, 0.1058 ± 0.0222, and 0.1036 ± 0.0186, respectively, 12 h - 72 h points) (P < 0.01, or P < 0.05). By ED intervention GRP78 (0.1550 ± 0.0131, 0.1886 ± 0.0154, and 0.1721 ± 0.0151, respectively, 12 h - 48 h points) positive cells value of the OD increased as compared with SC group (P < 0.01, or P < 0.05). and caspase-12 (0.1211 ± 0.0184, 0.1545 ± 0.0205, and 0.1085 ± 0.0219, respectively, 12 h, 24 h and 72 h points) positive cells value of the A decreased as compared with SC group (P < 0.01, or P < 0.05). (2) Measured by RT-PCR, the expression of GRP78 mRNA and caspase-12 mRNA trend was similar to protein. (3) The TUNEL positive cells in hippocampus CA(1) of SC group (11.41 ± 2.37) were more than that of NS group after the SC 12 h (P < 0.01), reached its highest level at 48 h (28.78 ± 5.11), after the intervention with edaravone (8.98 ± 2.22, 13.09 ± 2.54 and 20.57 ± 4.89, respectively, 12 h-48 h points), TUNEL positive cells showed a significant drop in SC group at 12 h-48 h time points (P < 0.01, or P < 0.05), but still significantly higher than that of the NS group (6.22 ± 1.50, 6.57 ± 1.61 and 6.72 ± 1.14, respectively) (P < 0.01, or P < 0.05), at the 4 h time point (NS group 6.29 ± 1.49, SC group 6.61 ± 1.71, ED group 5.75 ± 1.41) among the three groups, no significant difference in TUNEL positive cells was found (P = 0.759). CONCLUSIONS: The expression of GRP78 and caspase-12 increased after SC. Edaravone increased expression of GRP78 and decreased expression of caspase-12 in hippocampus rat with pilocarpine-induced seizures, reduced the number of neuronal apoptosis. These results suggest that edaravone may have protective effect against the hippocampal damage caused by status convulsive.

[Effects of W-7 on the expression of GRP78 and neuronal apoptosis in immature rat hippocampus after status convulsion].

OBJECTIVE: To investigate the effects of the calmodulin inhibitor W-7 on the expression of the key marker of ERS GRP78 and neuronal apoptosis in the immature rat hippocampus after status convulsion (SC). METHODS: One hundred and seventeen male Sprague-Dawley rats aged 19-21 days were randomly divided into three groups: normal saline control (control), SC with and without W-7 pretreatment. Each of the 3 groups was further subdivided into subgroups sacrificed at 4, 24 and 48 hrs. SC model was prepared using lithium-pilocarpine. GRP78 mRNA expression in the hippocampus was detected by semiquantitative reverse transcription-polymerase chain reaction (RT-PCR). GRP78 protein was ascertained by immunohistochemistry. Neuronal apoptosis was observed with TdT-mediated dUTP nick end labeling (TUNEL). RESULTS: The expression of GRP78 mRNA was significantly increased in the non-pretreated SC group compared with the control group 24 hrs after injection of saline or lithium-pilocarpine (P<0.01), and the expression of GRP78 protein also increased markedly in the seizure group compared with the control group 24 and 48 hrs after the injection (P<0.01). The expression of GRP78 mRNA and protein in the W-7 pretreatment group was significantly higher than both the control and the non-pretreated seizure groups 24 and 48 hrs after injection. The TUNEL positive cells in the hippocampus CA1 in the non-pretreated SC group 24 and 48 hrs after injection (21.0 ± 2.5 and 29.4 ± 2.8, respectively) were increased compared to the control group (7.1 ± 1.4 and 7.3 ± 1.6, respectively; P<0.01). W-7 pretreatment decreased TUNEL positive cells to 15.0 ± 2.5 and 20.0 ± 2.9 at 24 and 48 hrs after injection compared to the non-pretreated seizure group (P<0.01), but the number of TUNEL positive cells in the W-7 pretreatment group remained significantly greater than in the control group (P<0.01). CONCLUSIONS: W-7 may up-regulate the expression of GRP78 and reduce the number of apoptotic neurons, thus provides a neuroprotective effect against brain damage following SC.

[Expression of brain-derived neurotrophic factor and apoptosis in the brain of rats with repeated febrile seizures].

OBJECTIVE: To study the changes of brain-derived neurotrophic factor (BDNF) following repeated febrile seizures in rats and its possible correlation with neurocyte apoptosis. METHODS: Fifty-one male Sprague-Dawley (SD) rats were randomly assigned to three groups: normal control (n=14), febrile seizure (FS, n=18), hyperthermia alone (n=19). Febrile seizures were induced by hot water bath. The level of BDNF in the hippocampal homogenate was measured using ELISA and the expression of BDNF in various brain regions was measured by immunohistochemistry. The neurocyte apoptosis of the brain was determined by TdT-mediated biotinylated-dUTP nick end labling (TUNEL). RESULTS: The level of BDNF in the hippocampus in the FS group(89.9+/-12.5 ng/g)was higher than that in the normal control group(54.4+/-18.9 ng/g)and in the hyperthermia alone group (64.1+/-15.0 ng/g) (P<0.01). The OD value of BDNF positive neurons in various brain regions of the FS group was significantly higher than that of the normal control group (P<0.01) and the hyperthermia alone group (P<0.01). The FS group had significantly higher apoptotic index in various brain regions than the normal control and the hyperthermia alone groups (P<0.01). There was a positive correlation between the expression of BDNF and the apoptotic index in various brain regions (r=0.332, P<0.05). CONCLUSIONS: BDNF expression in the brain increases following repeated febrile seizures in rats, and the increased BDNF expression is correlated with neurocyte apoptosis.

[Protection of edaravone on neurons and its effects on the expression of interleukin-lbeta in juvenile rat hippocampus following status convulsion].

OBJECTIVE: To study the possible protection of edaravone on neurons of the hippocampus after status convulsion (SC) and its effects on the expression of interleukin-1beta (IL-lbeta) in juvenile rats. METHODS: One hundred and ninety-five juvenile male Sprague-Dawley rats were randomly divided into three groups: SC, edaravone pretreatment and normal saline control (control group). Each group was subdivided into five groups sacrificed at 4, 12, 24, 48 and 72 hrs after SC induction. SC model was prepared using lithium-pilocarpine. The edaravone pretreatment group received edaravone by intraperitoneal injection once daily three days before convulsion induction. Histopathologic changes in the hippocampus were viewed under a light microscope and an electron microscope. Expression of apoptosis cells was observed by TdT-mediated dUTP nick end labeling (TUNEL). Expression of IL-lbeta protein was determined by immunohistochemistry. RESULTS: Under the electron microscrope, a small quantity of neurons showed karyopycnosis and endocytoplasmic reticulum (ER) expanded remarkably 24 hrs after SC induction; at 48 hrs the ER expanding was alleviated somewhat but mitochomdria swelling was more severe. The edaravone pretreatment group showed less severe neuronal changes compared with the SC group under the microscopes. The TUNEL positive cells in the hippocampus of the SC group were significantly more than those of the control group 12 hrs, and peaked at 48 hrs after SC induction. The edaravone pretreatment group showed decreased TUNEL positive cells in the hippocampus compared with the SC group, although the positive cells were more than those in the control group between 12 and 48 hrs after SC induction. The immunohistochemistry assay demonstrated that the expression of IL-lbeta in the hippocampus of the SC group increased significantly compared with that of the control group 12, 24, 48 and 72 hrs after SC induction. Edaravone pretreatment resulted in a significantly decreased IL-lbeta expression in the hippocampus as compared with the SC group. CONCLUSIONS: Edaravone pretreatment may decrease the IL-1beta expression and neuronal apoptosis in the hippocampus. This suggests that edaravone may have protective effects against the hippocampal damage caused by SC.

[Effects of edaravone on the expression of interleukin-1beta, nuclear factor-kappaB and neuron apoptosis in juvenile rat hippocampus after status convulsion].

OBJECTIVE: To investigate the effect of edaravone on expression of interleukin-1beta (IL-1beta), nuclear factor-kappaB (NF-kappaB) and neuron apoptosis in the juvenile rat hippocampus after status convulsion (SC). METHODS: One hundred and ninety-five juvenile male Sprague-Dawley (SD) rats were randomly divided into normal saline (NS) control group, status convulsive group and edaravone treatment group. Each group was further divided into five subgroups for different time points. The rats in status convulsive group were kindled into epilepsy by lithium-pilocarpine chemical method. Expressions of IL-1beta and NF-kappaB proteins were detected with immunohistochemistry methods. Expression of NF-kappaB mRNA was detected with reverse transcription-polymerase chain reaction (RT-PCR). The neuron apoptosis was observed by TdT-mediated dUTP nick end labeling (TUNEL). RESULTS: (1) Measured by immunohistochemistry the value of IOD of IL-1beta (30.83 +/- 3.81, 41.00 +/- 5.61, 36.32 +/- 6.78 and 28.48 +/- 4.61, respectively, 12-72 h points) and NF-kappaB (67.60 +/- 5.81, 74.61 +/- 7.94, 82.43 +/- 10.67, 70.70 +/- 5.85 and 68.22 +/- 9.67, respectively, 4-72 h points) positive cells in the SC group increased,there was significant difference compared with NS group (IL-1beta: 11.74 +/- 2.32, 12.93 +/- 2.49, 13.02 +/- 2.83 and 12.98 +/- 5.29, respectively, 12-72 h points. NF-kappaB: 48.67 +/- 16.14, 44.62 +/- 7.82, 53.16 +/- 114.45, 54.27 +/- 5.25 and 55.56 +/- 7.56, respectively, 4-72 h points) (P < 0.01, or P < 0.05). By ED intervention in IL-1beta (22.01 +/- 4.45, 28.28 +/- 4.50 and 26.00 +/- 5.34, respectively, 12-48 h points) and NF-kappaB (58.56 +/- 6.37, 59. 86 +/- 6.73, 70.00 +/- 10.09, 64.78 +/- 7.56 and 64.45 +/- 6.51, respectively, 4-72 h points) positive cells value of the IOD decreased as compared with SC group (P < 0.01, or P < 0.05). (2) Measured by RT-PCR, the expression of NF-KB mRNA and protein trend was similar. (3)The TUNEL positive cells in hippocampus, CA1 of SC group (11.41 +/- 2.37) were more than that of NS group 12 h after the SC (P < 0.01), reached its highest level at48 h (28.78 +/- 5.11), after the intervention with edaravone (8.98 +/- 2.22, 13.09 +/- 2.54 and 20. 57 +/- 4.89, respectively, 12-48 h points) ,TUNEL positive cells showed a significant drop in SC group at 12-48 h time points (P < 0.01, or P < 0.05), but still significantly higher than that of the NS group (6.22 +/- 1.50, 6.57 +/- 1.61 and 6.72 +/- 1.14, respectively) (P < 0.01, or P < 0.05), at the 4 h time point(NS group 6.29 +/- 1.49, SC group 6.61 +/- 1.71, ED group 5.75 +/- 1.41) among the three groups, no significant difference in TUNEL positive cells was found (P = 0.759). CONCLUSIONS: Edaravone inhibited expression of IL-1beta and NF-kappaB in pilocarpine-induced seizures in rat hippocampus, reduced the number of neuronal apoptosis. These results suggest that edaravone may have protective effect against the damage caused by status convulsion.

[Effects of edaravone on IRE1 mRNA expression and neuronal apoptosis in the hippocampus of rats with status convulsivus].

OBJECTIVE: To investigate the expression of the key marker of endoplasmic reticulum stress (ERS) IRE1 mRNA and neuronal apoptosis in the rat hippocampus after status convulsivus (SC), and the intervention effects of edaravone, a novel free radical scavenger. METHODS: Sprague-Dawley (SD) rats aged 19-21 days were randomly assigned to three groups: normal control, SC and edaravone-treated SC. SC was induced in the later two groups. The two groups were subdivided into 5 groups sacrificed at 4, 12, 24, 48, and 72 hrs after SC induction. IRE1 mRNA expression in the hippocampus was detected by RT-PCR. Neuronal apoptosis was observed by TdT-mediated dUTP nick end labeling (TUNEL). The ultramicrostructural changes of neuron were observed by electron microscopy. RESULTS: IRE1 mRNA expression was obviously up-regulated 4 and 12 hrs after SC compared with the normal control group (P<0.01). IRE1 mRNA expression in the edaravone-treated SC group was notably higher than the untreated SC group 4, 12 and 24 hrs after SC and the normal control group (P<0.01). TUNEL positive cells in the hippocampus in the untreated SC group were significantly more than those in the normal control group (P<0.01). The number of TUNEL positive cells increased with the prolonged convulsion time. TUNEL positive cells in the edaravone-treated SC group were significantly reduced compared with those in the untreated SC group 12, 24, 48 and 72 hrs after SC (P<0.05 or P<0.01), but remained higher than the normal control group (P<0.05 or P<0.01). The peri-nucleus cell organ injuries were observed 4 hrs after SC and karyopycnosis and cytoplasm condensation were observed 12 hrs after SC in the SC and the edaravone-treated SC groups. The edaravone-treated SC group demonstrated less severe apoptosis than the untreated SC group. CONCLUSIONS: Edaravone may have neuroprotections against SC by an up-regulation of IRE1 expression. It might serve as an effective agent for reducing ERS in vivo.

[Unilateral spatial neglect in children with attention deficit hyperactivity disorder].

OBJECTIVE: To detect unilateral spatial neglect phenomenon in children with attention deficit hyperactivity disorder (ADHD) and to test the hypothesis that the phenomenon is associated with ADHD. METHODS: Thirty two boys met with ADHD diagnostic criteria of DSM-IV(TM) (ADHD group) and the 32 healthy boys without ADHD as control group participated in this study. All the participants received the flowing managements. The spatially sensitive tools of the Line Bisection test and the Star Cancellation test and some general measures (non-spatial) were used to evaluate spatial attention. RESULTS: (1) The score of Line Bisection test of boys with ADHD was (-9.37 +/- 6.57), and that of the control group was (-5.46 +/- 4.69), the difference between two groups was significant (t = -2.735, P < 0.01); the difference in left side score of the Star Cancellation test was statistically significant (t = -3.78, P < 0.01) in the ADHD group versus the control group (11.44 +/- 5.55 vs. 16.34 +/- 4.82), and the left side score was also lower than the right side one (17.13 +/- 6.36), the difference was significant (t = -3.09, P < 0.01). (2) Both groups' scores of the Line Bisection test were biased to the right side of "0" value respectively (ADHD group: t = -8.064, P < 0.01; control group: t = -6.585, P < 0.01), each side of which was lower versus "expected value" "27/27" on right side (ADHD group: t = -8.78, P < 0.01; control group: t = -7.39, P < 0.01) and left side (ADHD group: t = 15.85, P < 0.01; control group: t = -12.52, P < 0.01). CONCLUSIONS: The results suggest that left spatial neglect may be a common general phenomenon of school age boys. Compared with normal children, children with ADHD may have obvious left spatial neglect, which suggest that there be a common neurophysiologic mechanism between left spatial bias and ADHD.

[Applied anatomic investigation of phalloplasty ].

OBJECTIVE: To investigate the anatomy of penis and its adjacent organ for phalloplasty. METHODS: Anatomic dissection of penis and perineum was performed on 30 adult male cadavers (60 sides). Observation and measurement were focused on the penile length of different parts, the morphological relationship of infundibular ligament and suspensory ligament with penile radix, and the feature of crus penis with relation to the deep penile artery. RESULTS: The average length of the penile shaft was 8.13 cm, the penile radix was 7.67 cm and the crus penis was 5.96 - 5.98 cm. The deep penile artery penetrated into the crus penis at its middle 1/3. The infundibular ligament attached to superficial fascia of the penis and extended downward to the scrotal septum to constitute the suspensory structure for both of them. The suspensory ligament attached to the dorsal deep fascia of the penis. Becoming thicker, the rear part of the suspensory ligament connected firmly to the pubic arcuate ligament to constitute a part of suspensory mechanism for the urethra. There was a part of cavernous body, which was free from either ligament or bony attachment, between the penile radix and the crus penis, where the dorsal artery and nerve of penis turned around from the ventral to the dorsal aspect of the penis and the penile dorsal vain penetrated the urogenital septum, draining into intrapelvic venous plexus. CONCLUSIONS: The divisional measurement of the penis length, the recognition of the suspensory ligaments and the anatomic feature of the crus penis with relation to the deep penile artery are all of significant importance to improve the operation of phalloplasty.