[Hereditary hemorrhagic telangiectasia: a report of two cases].

This article reports two children with hereditary hemorrhagic telangiectasia (HHT). Patient 1 was a boy aged 12 years and was admitted due to intermittent cough and wheezing for more than 10 years. This boy and his mother and grandmother had a history of epistaxis. The boy had a history of the rupture of cerebral arteriovenous malformations. Gene detection showed a heterozygous mutation, c.277C>T(p.Arg93*), in the ENG gene. Patient 2 was a girl aged 13 years and was admitted due to cyanosis of lips for more than 1 year. The girl had a history of recurrent epistaxis and the manifestations of severe decline in pulmonary diffuse function, pulmonary hypertension, dilation of blood vessels at the distal end of lungs, and small arteriovenous communications in both lungs. Children with HHT often lack typical respiratory symptoms, which may lead to missed diagnosis and misdiagnosis in the early stage. Pulmonary computed tomography or right cardiac acoustic contrast can help with the diagnosis of HHT, and gene detection can improve the early diagnostic rate of this disease.

[Clinical features of neuroendocrine cell hyperplasia of infancy].

OBJECTIVE: To study the clinical features of neuroendocrine cell hyperplasia of infancy (NEHI) in order to provide a basis for the management of diagnosis, treatment and prognosis of children with NEHI. METHODS: A retrospective analysis was performed for the clinical data of seven children with NEHI who were diagnosed and treated from January 2014 to March 2016. RESULTS: Among the seven children with NEHI, there were five boys and two girls. Two children experienced tachypnea since the neonatal period, and five children developed respiratory tract symptoms within 1-6 months after birth. Of the 7 children, 6 had pulmonary crackles, 4 had hypoxemia, and 3 had gastroesophageal reflux. Lung high-resolution CT (HRCT) showed ground-glass opacities in the central region of the lungs in all children, which involved at least two lung lobes. Of the 7 children, 2 had the involvement of more than 4 lobes and 6 had air trapping. All 7 children had an improvement in clinical symptoms after two years of age. One child achieved clinical and CT remission. Four children achieved clinical remission, but still with CT changes. CONCLUSIONS: NEHI often occurs in infancy, with the major clinical manifestations of persistent tachypnea, pulmonary crackles, and hypoxemia. The children with NEHI often present ground-glass opacities in the central region of the lungs and air trapping on HRCT. There is no specific treatment for this disease and most cases have a good prognosis.

[Cyanosis for more than 4 years in a girl aged 4 years and 3 months].

A girl, aged 4 years and 3 months, presented with cyanosis of the lips shortly after birth. She then experienced shortness of breath after activity 1 year ago and acrocyanosis 3 months ago, with obvious acropachy and toe deformity. Laboratory examinations revealed an increase in hemoglobin (178 g/L) and a reduction in arterial partial pressure of oxygen (37.7 mm Hg). Plain and contrast-enhanced CT scans of the lungs showed a large area of dense shadow and multiple nodules with clear boundaries in the right lower lung, as well as thickening of the arteries and dilatation of the veins in the right lower lung. Magnetic resonance angiography of the pulmonary artery showed large arteriovenous malformation in the lung. The child was diagnosed with congenital pulmonary arteriovenous fistula and was given interventional embolization of the pulmonary arterial fistula. The child was followed up at 3 months after surgery. The symptoms of shortness of breath and cyanosis disappeared, and activity tolerance, heart rate, hemoglobin, red blood cell count, and transcutaneous oxygen saturation all returned to normal.

[Acute fever with rash, necrosis, and bullae in both lower extremities in a 12-year-old girl].

A girl, aged 12 years, was admitted due to fever and rash for 3 days. The child developed recurrent high fever and rash on both lower extremities 3 days before, and the rash on left lower extremity quickly merged into a patch within 24 hours, with hemorrhage and necrosis in black and purple, large vesicles, and blisters in the center. Laboratory examination showed a reduction in platelet count and significant increases in fibrinogen and D-dimer during the course of the disease. The child was diagnosed with purpura flulminans. She was given meropenem combined with linezolid for anti-infection, injection of gamma globulin for immunoregulation, and low-molecular-weight heparin for anticoagulation. The fluid in the rash blisters was drawn and the wound was treated to prevent infection. The child's temperature returned to normal, with improvement in gangrene. She was discharged after platelet count, fibrinogen, and D-dimer had returned to normal. Purpura fulminans is a rare thrombotic hemorrhagic disease with rapid progression and is commonly seen in children. Without timely treatment, it may cause severe sequelae with high disability and mortality rates. Anti-infection, correction of coagulation function, and local management of gangrene skin are of great importance during treatment.

[Liver dysfunction for 8 years with hypertension for 1 week in an 8-year-old girl].

A girl, aged 8 years, developed jaundice and liver dysfunction in the neonatal period, with congenital glaucoma diagnosed on day 5 after birth, hypertension and unusual facies (broad forehead, hypertelorism and deep-set eyes). Cholestasis was the main type of liver dysfunction. Cardiac macrovascular CTA showed stenosis at the abdominal aorta and the beginning of the bilateral renal arteries. Whole exon sequencing revealed a heterozygous frameshift mutation, c.1485delC (absence of cytosine), in exon 12 of the JAG1gene. The girl was diagnosed with Alagille syndrome and was given transaminase-lowering, cholagogic and antihypertensive treatment with multiple drugs. There were significant reductions in serum levels of alanine aminotransferase, aspartate aminotransferase and total bile acid, but blood pressure fluctuated between 102-140 mm Hg/53-89 mm Hg. After renal artery angiography and balloon dilatation angioplasty, the girl was given oral administration of antihypertensive drugs, and blood pressure was controlled at a level of 110-120 mm Hg/60-80 mm Hg. The rare disease Alagille syndrome should be considered when a child has refractory hypertension with the involvement of multiple systems, especially liver dysfunction with cholestasis as the main manifestation. Genetic causes should be analyzed for a early diagnosis.

[Effect of budesonide aerosol treatment on expression of glucocorticoid receptor and nuclear factor-κB in asthmatic mice].

OBJECTIVE: To study the effect of budesonide aerosol inhalation on the expression of glucocorticoid receptor (GR) and nuclear factor (NF)-κB in asthmatic mice. METHODS: Twenty-four healthy male BALB/c mice aged 6 to 8 weeks were randomly divided into three groups (n=8 each): normal saline (control group), asthma model (asthma group) and budesonide-treated asthma (BUD group). Asthma was induced by intraperitoneal injection of ovalbumin (OVA) and aluminium hydroxide suspension and aerosol inhalation of OVA solution. Mice were sacrificed 24 hours after the last challenge. Eosinophil count in the bronchoalveolar lavage fluid (BALF) was determined. Pathological examination of the lung tissues was performed and the expression levels of GR and NF-κB were measured by immunohistochemical analysis. RESULTS: Eosinophil count in the BALF was significantly higher in the asthma and BUD groups than in the control group (P<0.05). BUD treatment decreased eosinophil count in the BALF compared with the asthma group (P<0.05). The lung tissues in the BUD group showed a less severe infiltration of eosinophils and lymphocytes compared with the asthma group. The percentage of GR-positive cells in the asthma group decreased significantly compared with the control group (P<0.05), and the percentage of GR-positive cells in the BUD group increased significantly compared with the asthma group (P<0.05). Compared with the control group, the percentage of NF-κB-positive cells increased significantly in the asthma group (P<0.05), and the percentage of NF-κB positive cells in the BUD group was significantly reduced compared with the asthma group (P<0.05). CONCLUSIONS: The action mechanism of budesonide in treating asthmatic mice may be related to the upregulation of GR expression and the inhibition of NF-κB activity.

A prepared anti-MSTN polyclonal antibody reverses insulin resistance of diet-induced obese rats via regulation of PI3K/Akt/mTOR&FoxO1 signal pathways.

Suppression of myostatin (MSTN) is associated with skeletal muscle atrophy and insulin resistance. However, the mechanisms by which MSTN regulates insulin resistance are not well known. We have explored the signaling pathways through which MSTN regulates insulin resistance in diet-induced obese rats using a polyclonal antibody for MSTN. The anti-MSTN polyclonal antibody significantly improved insulin resistance and whole-body insulin sensitivity, decreased MSTN protein expression in muscle samples by 39% in diet-induced obese rats. Furthermore, the anti-MSTN polyclonal antibody significantly enhanced PI3K activity (140%), Akt phosphorylation (86%), GLUT4 protein expression (23%), the phosphorylation of mTOR (21%), and inhibited the phosphorylation of FoxO1 (57%), but did not affect the phosphorylation of GSK-3ß. Thus, suppression of MSTN by the anti-MSTN polyclonal antibody reverses insulin resistance of diet-induced obesity via MSTN/PI3K/Akt/mTOR and MSTN/PI3K/Akt/FoxO1 signaling pathways.

[Clinical and electrophysiological characteristics, and prognosis of acute motor axonal neuropathy in children].

OBJECTIVE: To investigate the clinical and electrophysiological characteristics and prognosis of acute motor axonal neuropathy (AMAN) in children in South China. METHODS: The clinical and electrophysiological data of 6 children with AMAN was analyzed, and they were followed up. RESULTS: The mean age of onset was 4.4 years. Most patients came from rural areas and 5 cases had a history of prodromal infection. There were no seasonal differences in clinical onset among the patients. The most common first symptom was muscle weakness, and the mean time from onset to the most severe disease status was 4.2 days. Nerve conduction test results revealed that all patients showed significantly lower amplitude of motor nerve action potential, only 22.3%-73.4% of the lower limit of normal. Injury to the nerves of distal extremities was more serious than injury to the nerves of proximal extremities (P<0.05), while there was no significant difference in the injury to the nerves of upper and lower extremities (P>0.05). Motor nerve conduction velocity and sensory nerve conduction velocity were normal. All patients received intravenous immunoglobulin (IVIG). Of the 6 AMAN patients, 4 could walk independently after a follow-up of 3 months to 1 year. CONCLUSIONS: AMAN in children occurs mostly in rural areas. There is no seasonal difference in the clinical onset of the disease. Muscle weakness is the most common first symptom and the worst status of AMAN appears in the early stage of the disease. Electrophysiological examination provides important information for the diagnosis of AMAN. Some children with AMAN regain the ability to walk independently 1 year after onset. Early application of IVIG treatment may help recovery of neural function.

[Succinic semialdehyde dehydrogenase deficiency].

Succinic semialdehyde dehydrogenase (SSADH) deficiency is a rare autosomal recessive disorder. This paper reports three cases of SSADH deficiency in infants. The infants developed the symptoms including developmental delay, intellectual disability, hypotonia, hyporeflexia and seizures. The electroencephalogram (EEG) showed background slowing and focal spike discharges in all of 3 patients. Head magnetic resonance imaging (MRI) demonstrated abnormalities in 2 patients, including basal ganglia damage and increased T2-weighted signal in bilateral cerebral peduncles. Urinary organic acid analysis with gas chromatography-mass spectrometry (GC-MS) revealed increased levels of 4-hydroxybutyrate (GHB) in 3 patients. SSADH deficiency was definitely diagnosed based on the clinical manifestations and the results of urinary organic acid analysis in the 3 children. It was concluded that early urine organic acid analysis is essential for children presenting with mental retardation, neuropsychiatric disturbance or epilepsy of unknown etiology.

The role of peripheral type 2 innate lymphoid cells in bronchiolitis.

Our aim was to detect type 2 innate lymphoid cells (ILC2s)-related cytokines of infants with bronchiolitis by using Elisa, Liquidchip technology and RT-PCR and investigated its correlation with bronchiolitis. We recruited 26 infants with bronchiolitis and 20 healthy infants as control from Xiangya Hospital. Compared to the control group, the serum levels of interleukin-5 (IL-5) [41.99 (21.11) vs 25.70 (19.64)], IL-9 [27.04 (37.51) vs 8.30 (0.54)], IL-13 [184.05 (132.81) vs 121.75 (176.13)], IL-33 [83.70 (46.69) vs 11.23 (55.31)] and thymic stromal lymphopoietin (TSLP) [31.42 (5.41) vs 28.76 (2.56)] were significantly increased in infants with bronchiolitis (P < 0.05), while the level of IgE had no significant difference between the two groups [19.05 (14.15) vs 14.85 (20.2), P > 0.05]. The mRNA expression of IL-17RB (9.83 ± 0.35 vs 9.19 ± 0.58), TSLP (16.98 ± 2.12 vs 15.07 ± 2.25), retinoid acid receptor related orphan receptor α (7.18 ± 0.71 vs 5.46 ± 1.09) and trans-acting T-cell-specific transcription factor 3 (4.86 ± 0.66 vs 4.19 ± 0.90) were significantly increased in infants with bronchiolitis versus the control group (P < 0.05), while there was no statistical significance for suppression of tumorigenicity 2 (5.59 ± 0.68 vs 5.41 ± 0.87, P > 0.05). Our findings suggested that ILC2s possibly play a specific role in immunopathology of bronchiolitis.

[Effect of intracerebral transplantation of rat bone marrow stromal cells on brain white matter of neonatal rats with hypoxic-ischemic brain damage].

OBJECTIVE: To study the effect of intracerebral transplantation of bone marrow stromal cells (BMSCs) on brain white matter of neonatal rats with hypoxic-ischemic brain damage (HIBD). METHODS: Thirty-four 7-day-old neonatal rats were randomly assigned to three groups: normal control (n=10), HIBD (n=12) and HIBD+BMSCs transplantation (n=12). The HIBD and the HIBD+BMSCs transplantation group rats were subjected to left carotid artery ligation, followed by hypoxia exposure for 2 hrs, in order to induce HIBD. The rats in the HIBD+BMSCs transplantation group received transplantation of BMSCs labeled nucleus with Hochest 33324 into the left hippocampus 24 hrs after HIBD induction. Myelin basic protein (MBP) expression in the left corpus callosum and the subcortical white matter and the number of oligodendrocyte precursors positively stained O4 in the left periventricular area and the subcortical white matter were detected by immunohistochemistry at ages of 45 days. RESULTS: The labeled BMSCs survived and were found mainly in the left hemisphere 37 days after transplantation. The positive rate of O4 expressed by the transplanted BMSCs was 3.70+/-1.09%. More hypomyelination in the left corpus callosum and the subcortical white matter, and less number of O4 positive oligodendrocytes in the left periventricular area and the subcortical white matter were found in the HIBD group compared with the normal control group (P<0.01). The HIBD rats receiving BMSCs transplantation had increased O4 positive oligodendrocytes in the left periventricular area and the subcortical white matter and improved MBP immunoreactivity in the left corpus callosum and the subcortical white matter compared with the HIBD group (P<0.01). CONCLUSIONS: Intracerebral transplantation of BMSCs can improve brain white matter damage in neonatal rats with HIBD.

Knockdown of SALL4 overcomes cisplatin-resistance through AKT/mTOR signaling in lung cancer cells.

Drug resistance is an important factor for the poor prognosis of non-small cell lung cancer (NSCLC). Sal-like protein 4 (Sall4) is a stem cell marker, and plays a role in maintaining self-renewal. Previous studies have demonstrated that Sall4 may be a candidate for use as support in the diagnosis of lung cancer, and may also represent a therapeutic target. However, the role of Sall4 on drug resistance of lung cancer cells and the mechanism by which Sall4 regulates the sensitivity of lung cancer cells to cisplatin (DDP) remains unknown. In this study, we aim to investigate whether knockdown of Sall4 by siRNA can enhance the apoptosis induced by cisplatin in lung cancer cells. We here reported that the expression of Sall4 was dramatically upregulated in cisplatin-resistant A549 cells compared with the parental cells. Knockdown of Sall4 by siRNA in cisplatin-resistant A549 cells reduced the IC50 compared with the parental cells. In addition, knockdown of Sall4 significantly inhibited cell proliferation, induced apoptosis and invasion cisplatin-resistant A549 cells through AKT/mTOR signaling. Our findings demonstrate that Sall4 is an essential regulator in cisplatin-induced apoptosis, and knockdown of Sall4 may restore cisplatin sensitivity in acquired resistant cells. Thus, our study provides an effective therapeutic strategy for NSCLC treatment.

IL-17A and GDF15 are able to induce epithelial-mesenchymal transition of lung epithelial cells in response to cigarette smoke.

Smoking is one of the primary causes of chronic obstructive pulmonary disease (COPD). Sustained active epithelial-mesenchymal transition (EMT) in COPD may explain the core pathophysiology of airway fibrosis and why lung cancer is so common among smokers. Interleukin (IL)-17A and growth/differentiation factor (GDF)15 have been reported to be biomarkers of COPD; however, the role of IL-17A and GDF15 in EMT remains unclear. The aim of the present study was to investigate the role of IL-17A and GDF15 in the pathogenesis of COPD. It was demonstrated that IL-17A and GDF15 are upregulated in patients with COPD, particularly those with a history of smoking. The results also revealed that IL-17A and GDF15 expression was negatively correlated with the epithelial marker epithelial-cadherin and positively correlated with the mesenchymal marker vimentin. Furthermore, treatment with cigarette smoke extract or IL-17A induced GDF15 expression. Combined treatment with IL-17A and GDF15 induced EMT in human small epithelial HSAEpiC cells in vitro. Collectively, the results of the present study suggest that IL-17A and GDF15-induced EMT serves an important role in the pathology of COPD.

Proliferation of neural stem cells correlates with Wnt-3 protein in hypoxic-ischemic neonate rats after hyperbaric oxygen therapy.

Hyperbaric oxygen therapy promoted brain cell proliferation. Wnt-3 is closely associated with the proliferation of neural stem cells. We examined whether hyperbaric oxygen promoted neural stem cells to proliferate and its correlation with Wnt-3 protein in hypoxic-ischemic neonate rats. Hyperbaric oxygen therapy was administered 3 h after hypoxia ischemia daily for 7 days. The proliferating stem cells and Wnt-3 protein were examined dynamically in the subventricular zone. Results showed that stem cells proliferated and peaked 7 days after hyperbaric oxygen therapy. Wnt-3 protein increased to the higher levels 3 days after therapy. Linear regression analysis showed that nestin protein correlated with Wnt-3 protein. We propose that hyperbaric oxygen treatment promote stem cells to proliferate, which is correlated with Wnt-3 protein.

[Effect of hepatocyte growth factor on proliferation and apoptosis of hyperoxia exposed type II alveolar epithelial cells isolated from premature rat lungs].

OBJECTIVE: To explore the effect of hepatocyte growth factor (HGF) on the proliferation, apoptosis and function of hyperoxia exposed Type II alveolar epithelial cells (AEC II) isolated from premature rat lungs, and to explore the mechanism of the protective effect of HGF on hyperoxia-induced lung injury. METHODS: Type II alveolar epithelial cells from fetal rat lungs were cultured. After being purified, AEC II was randomly divided to 4 groups: air group (Air), hyperoxia group (HO), air plus hepatocyte growth factor group (Air+HGF), hyperoxia plus hepatocyte growth factor group (HO+HGF) . The mRNA levels of surfactant associated protein, SPs (including SPA, SPB, SPC) were measured by RT-PCR. The proliferation and apoptosis of AEC II were analyzed with flow cytometric assay and Western blot. RESULTS: (1) Compared with Air group, the apoptosis rate increased significantly in the HO group, while G(2)/M phase percentage and the protein expression levels of proliferating cell nuclear antigen (PCNA) decreased significantly (P<0.01); the S phase percentage and the protein expression levels of PCNA increased significantly in the Air+HGF group. (2) In the HO +HGF group, the apoptosis rate was not significantly different, G0/G1 phase percentage decreased significantly, S phase, G(2)/M phase percentage and the protein expression levels of PCNA increased significantly compared with the HO group. (3) SPs mRNA levels significantly decreased in the HO group compared with those in the Air group. After HGF was added, SPs mRNA levels increased in the HO +HGF group and the Air+HGF group compared with the HO group. CONCLUSION: Hyperoxia can inhibit the proliferation, increase the apoptosis rate and decrease SPs mRNAs levels of AEC II in vitro in premature rats, while HGF can partly inhibit the changes of SPs mRNAs levels and cell proliferation of AEC II resulted from hyperoxia, and HGF may play a protective role in hyperoxia-induced lung injury.

[Differentiation of rat bone marrow stromal cells into neural cells induced by hypoxic-ischemic brain tissue extracts in neonate rats].

OBJECTIVE: To investigate the effect of brain tissue extracts in neonate rats with hypoxic-ischemic brain damage (HIBD) on the differentiation of bone marrow stromal cells (BMSCs) into neural cells. METHODS: Fifteen 7-day-old neonate rats were induced HIBD by left carotid artery ligation and hypoxia exposure, and another 15-day-old neonate rats were served as normal rats. The left and right brain tissue extracts of the normal and HIBD rats were prepared 24 h after the HIBD (8-day old), 72 h after the HIBD (10-day old), and 7 d after the HIBD (14-day old), respectively (n=5). The rat BMSCs of passage 3-5 were cultured in the medium with or without previous brain tissue extracts. The expressions of neuron specific enolase (NSE), glial fibrillary acidic protein (GFAP) and O(4) marked oligodendrocyte were detected after 3 days by immunocytochemistry. RESULTS: The expressions of NSE, GFAP and O(4) of BMSCs cultured in the medium with left or right brain tissue extracts of different day old normal rats were higher than those of BMSCs cultured without the extracts, respectively (P<0.01), and the expressions of NSE, GFAP and O(4) of BMSCs cultured in the medium with left brain tissue extracts of 8 day old and 10 day old HIBD rats were higher than those of BMSCs cultured with right brain tissue extracts of the same day HIBD rats and BMSCs cultured with left or right brain tissue extracts of the same day normal rats (P<0.01 or P<0.05). The expressions of NSE, GFAP and O(4) of BMSCs cultured in the medium with left brain tissue extracts of 8-day-old HIBD rats were higher than those of BMSCs cultured with left brain tissue extracts of 10-day-old and 14-day-old HIBD rats (P<0.01 or P<0.05). CONCLUSION: The brain tissue extracts of normal and HIBD rats can induce BMSCS into neural cells, and the damaged brain tissue extracts of 8-day-old HIBD rats is the best inductor.

[Changes of Wnt-3 protein during the proliferation of endogenous neural stem cells in neonatal rats with hypoxic-ischemic brain damage after hyperbaric oxygen therapy].

OBJECTIVE: Previous studies suggest that hyperbaric oxygen (HBO) treatment promotes the proliferation of neurocytes in neonatal rats following hypoxic-ischemic brain damage (HIBD). The Wnt signaling pathway is associated with neurogenesis. This study examined whether HBO promoted neural stem cells (NSCs) proliferation after HIBD, and whether that the proliferation correlated with Wnt-3 protein expression. METHODS: Seven-day-old Sprague-Dawley rats were randomly divided into three groups: normal control, hypoxia-ischemia (HI), and HI-HBO. HI was induced by the ligation of left common carotid artery, followed by a 2-hr exposure to 8% O2 in the latter two groups. HBO was administered 3 hrs after HI in the HI-HBO group for continuous 7 days (2 atmospheres absolute, once daily). The proliferating NSCs in the subventricular zone (SVZ) was examined by BrdU/nestin immunofluorescence and the expression of Wnt-3 protein in NSCs was examined by nestin/Wnt-3 immunofluorescence at 6 and 24 hrs and at 3, 7 and 14 days of HI. The cellular expressions of nestin and Wnt-3 protein were analyzed by laser scanning confocal microscopy. The linear regression analysis was used to evaluate the correlation between cellular Wnt-3 and nestin protein. The expressions of nestin and Wnt-3 protein in the ischemic cerebral hemisphere were analyzed with Western blotting. RESULTS: The number of BrdU/nestin positive cells in the SVZ increased 3 hrs after HBO therapy, peaked at 7 days and remained at a higher level until 14 days after HBO therapy in the HI-HBO group compared with the normal control and the HIBD groups. The level of Wnt-3 protein in NSCs increased significantly 3 hrs after HBO therapy, peaked at 3 days and remained at high levels until 14 days after HBO therapy in the HI-HBO group compared with the normal control and the HIBD groups. The level of cellular nestin protein was closely correlated with the level of cellular Wnt-3 protein (r = 0.893, P < 0.05). The Western blotting analysis demonstrated increased Wnt-3 and nestin protein expressions in the ischemic cerebral hemispheres. CONCLUSIONS: HBO treatment promotes the proliferation of NSCs in HIBD neonatal rats, which is correlated with the activation of Wnt signaling.

[Effect of hyperbaric oxygen therapy administered at different time on white matter damage following hypoxic-ischemic brain damage in neonatal rats].

OBJECTIVE: A recent study has suggested that hyperbaric oxygen (HBO) therapy administered within 3 hrs following hypoxic-ischemic brain damage (HIBD) may alleviate brain white matter damage (WMD) in neonatal rats. However it is unclear whether a delayed HBO therapy (more than 3 hrs following HIBD) has neuroprotective effects in neonatal rats. This study aimed to explore the effect of HBO therapy administered at different time points following HIBD on WMD in neonatal rats. METHODS: The HIBD model was prepared according to the Rice-Vannucci procedure in 7-day-old Sprague-Dawley rats. HBO therapy was administered at 3, 6, 12, 24 or 72 hrs after HIBD, once daily for consecutive 7 days. T-maze test, the foot-fault test and the radial arm maze test were performed after 14 days of HIBD. Myelin basic protein (MBP) in the callositas and corpora striata was examined by immunohistochemical method 28 days after HIBD. RESULTS: The rats receiving HBO therapy at 3, 6 and 12 hrs after HIBD performed significantly better in the T-maze test, the radial arm maze test and the foot-fault test than the untreated HIBD rats. There were no significant differences in the behavioral test results between the HBO-treated groups administered HBO at 24 and 72 hrs after HIBD and the untreated HIBD group. The MBP expression in the HBO-treated groups treated within 12 hrs after HIBD was significantly higher than that in the untreated HIBD group (P < 0.05). When the HBO therapeutic window was delayed to 24 hrs after HIBD, there were no significant differences in the MBP expression between the HBO-treated and the untreated HIBD groups. CONCLUSIONS: HBO therapy administered within 12 hrs following HIBD can alleviate brain WMD in neonatal rats, but the efficacy of HBO therapy administered 24 hrs after HIBD does not appear to be satisfactory.

[Effect of hyperbaric oxygenation on neural stem cells and myelin in neonatal rats with hypoxic-ischemic brain damage].

OBJECTIVE: This study investigated the effect of hyperbaric oxygenation (HBO) on neural stem cells (NSCs) and myelin in neonatal rats following hypoxic-ischemic brain damage (HIBD) and aimed to explore the possible mechanism of the protective effect of HBO on HIBD. METHODS: Seven-day-old Sprague-Dawley rat pups were randomly assigned into 4 groups: Normal control, HIBD, hyperbaric air (HBA), and HBO groups (n=30 each). The HIBD model was produced by permanent occlusion of the left common carotid artery and 2 hrs hypoxemia exposure (8% O2 at 37 degrees C). HBA and HBO treatment was administered (2 ATA, once daily for 7 days) in the HBA and HBO groups respectively 1 hr after HIBD. BrdU immunohistochemistry was used to detect the NSCs in the sub-ventricle zone (SVZ) of the lateral ventricle and the dentate gyrus (DG) of the hippocampus. The myelin damage was assessed by myelin basic protein (MBP) immunostaining. RESULTS: The BrdU-positive cells in the SVZ and the DG of the ischemic hemisphere in the HIBD group were dramatically decreased compared with those of the Normal control group at 3 weeks post-HIBD (P < 0.01). The HBO treatment resulted in an increase of BrdU-positive cells in the DG from 153.7 +/- 37.0 to 193.7 +/- 38.8 (P < 0.05). The nestin expression in the HIBD and HBA groups was reduced compared with that in the Normal control group. There was no difference in the nestin expression between the HBO and the Normal control groups. Hypoxia-ischemia (HI) led to marked myelin damage at 1 week post-HIBD. HBO or HBA treatment alleviated the damage. CONCLUSIONS: The HBO treatment can result in the proliferation of BrdU-positive cells and alleviate the myelin damage following HIBD in neonatal rats, thereby offering neuroprotectivity against HI insults.