Objective To study the relationship between nasal carriage and Staphylococcus aureus (S. aureus) infection in hospitalized children. Methods Fifty-six hospitalized children infected with S. aureus were recruited in this study. Nasal swabs were collected and cultured, and the nasal carriage rate of S. aureus was examined. PVL virulence gene and mecA resistance gene were both detected in clinical strains and nasal carriage strains by PCR. Results Twenty-two (39%) of the 56 children had nasal carriage of S. aureus, and most of them (18 cases) were younger than one year. Among these 22 children, 11 (50%) had previous hospitalization over the past year. In the infected strains, the rate of methicillin-resistant S. aureus (MRSA) was 29% (16/56), while it was 32% (7/22) in carriage strains. The mecA positive results in clinical strains were consistent with the results in nasal carriage strains. Among 5 PVL-positive nasal carriage strains, 4 (90%) could be matched with their clinical strains, all of which were MRSA. Conclusions Nasal carriage is a potential risk factor for S. aureus infection. Nosocomial transmission may lead to nasal carriage, which can cause S. aureus infection. The isolation rate of MRSA is high in hospitalized children infected with S. aureus, which implies that more attention is needed for this situation. The isolates from noses may be clonally identical to the isolates from clinical secretions, and the homology between them needs to be confirmed by multi-locus sequence typing.
Objective To investigate the antimicrobial resistance of invasive and non-invasive Streptococcus pneumoniae (SP) strains in children and to provide a basis for proper use of antimicrobial drugs in the treatment of SP infection. Methods Seventy children who were diagnosed with invasive pneumococcal diseases (IPD) between January 2009 and December 2013 were enrolled, and 164 children with lower respiratory tract infection caused by SP were randomly selected as the control group. The samples from sterile sites (blood, cerebrospinal fluid, etc) of children with IPD, as well as the sputum samples of children in the control group, were collected for bacterial culture, and the drug susceptibility tests for isolated SP strains were conducted. Results A total of 82 invasive strains of SP were isolated from sterile sites of 70 children with IPD; 49 strains (60%) were isolated from blood, and 19 strains (23%) from cerebrospinal fluid. The detection rate of invasive SP strains decreased from 2009 to 2013 (P<0.01). The total detection rates of penicillin-nonsusceptible SP from the invasive and non-invasive strains were 27% and 17% respectively (P>0.05). Among invasive strains, the penicillin-nonsusceptible SP strains had significantly higher rates of insusceptibility to cefotaxime, ceftriaxone, and cefepime than the penicillin-susceptible SP (P<0.01). There were significant differences in the rates of insusceptibility to cefotaxime, ceftriaxone, and meropenem between the sensitive and non-sensitive SP strains (P<0.05). The multidrug resistance rates of the invasive and non-invasive SP strains were 89% and 93% respectively (P>0.05). Conclusions Invasive SP can easily invade the blood in children, but the total detection rate has decreased year by year. The results of drug sensitivity tests have guiding significance for proper use of antimicrobial drugs for different SP infections.
Objective To investigate the clinical significance of T helper type 9 (Th9) cells and interleukin-9 (IL- 9) in children suffering from Mycoplasma pneumoniae (MP) infection. Methods A total of 86 children who were diagnosed with MP infection between January 2013 and June 2014 were classified into upper respiratory infection (URI) group (n=29), mild MP pneumonia (MPP) group (n=32) and severe MPP group (n=25). Twenty-eight healthy children were used as the control group. Peripheral blood mononuclear cells were isolated by Ficoll density gradient centrifugation, and the percentage of Th9 cells in peripheral blood was measured by flow cytometry. Serum IL-9 level was determined using ELISA. Results The URI, mild MPP, and severe MPP groups had significantly higher percentages of Th9 cells and IL-9 levels than the control group (P<0.05); the mild MPP and severe MPP groups had significantly higher percentages of Th9 cells and IL-9 levels than the URI group (P<0.05), and the two indices were significantly higher in the severe MPP group than in the mild MPP group (P<0.01). Conclusions Children with MP infection have an elevated percentage of Th9 cells and IL-9 expression, both of which are positively correlated with the severity of the disease. It can be predicted that Th9 cells and IL-9 can be used as evaluation indicators for the progression and outcome of children with MP infection.
Objective To determine the frequencies and significance of myeloid-derived suppressor cells (MDSCs) and T-helper 17 (Th17) cells in peripheral blood of young children with recurrent wheezing. Methods Thirty young children with an acute exacerbation of recurrent wheezing were randomly enrolled. Twenty age-matched children with bronchopneumonia (pneumonia group) and 23 age-matched preoperative children with non-infectious or nonneoplastic diseases (hernia or renal calculus) (control group) were selected. The frequencies of MDSCs and Th17 cells in the peripheral blood were measured using flow cytometry and their correlation was determined by the Spearman’s correlation coefficient. Results The percentage of MDSCs in nucleated cells was significantly higher in the wheezing group than in the pneumonia and control groups (P<0.05), and it was significantly higher in the pneumonia group than in the control group (P<0.05). The percentage of Th17 cells in mononuclear cells was significantly higher in the wheezing group than in the pneumonia and control groups (P<0.05), but it showed no significant difference between the pneumonia and control groups (P>0.05). The frequency of MDSCs was positively correlated with the frequency of Th17 cells in the wheezing group (r=0.645, P<0.01). Conclusions MDSCs and Th17 cells may contribute to the pathogenesis of recurrent wheezing in young children.
Objective To examine fractional exhaled nitric oxide (FeNO) values in 1-3-year-old children with asthma and analyze the correlation of FeNO with peripheral blood eosinophils (EOS) and lung function in these children. Methods A total of 111 children aged 1-3 years with asthma were enrolled. The children were classified into acute exacerbation (n=62) and remission groups (n=49) according to their symptoms. FeNO values, lung function, and peripheral blood EOS count were measured in these children. Sixty age-matched healthy children were enrolled as the control group. Results FeNO values were significantly higher in the acute exacerbation group (24.4 ppb) than in the remission group (18.0 ppb) and the control group (13.7 ppb) (P<0.05). The FeNO values in the remission group were significantly higher than in the control group (P<0.05). FeNO values were not significantly correlated with peripheral blood EOS count and lung function parameters (PEF, TEF25, TEF50, and TEF75) . Conclusions Measurement of FeNO is useful to evaluate the disease activity in children with asthma aged 1 to 3 years, but the FeNO values are not correlated with peripheral blood EOS count and lung function.
Objective To study the clinical features of children with relapsed acute lymphoblastic leukemia (ALL) treated with the CCLG-ALL2008 protocol. Methods The data of 591 children who were newly diagnosed with ALL and were treated with the CCLG-ALL 2008 protocol between April 2008 and June 2013 were collected, and the clinical features of 80 children with relapsed ALL were retrospectively analyzed. Results After treatment with the CCLGALL2008 protocol, the recurrence rate in the standard-risk, intermediate-risk and the high-risk groups were 7.0%, 10.7% and 28.7% respectively (P<0.05). The recurrence rate in patients with TEL/AML1-positive ALL was 8.0%, and the 5-year overall survival (OS) of the relapsed patients was 37.04%. The recurrence rates in patients with MLL-positive and BCR/ABL-positive ALL were 35.0% and 24.2% respectively, and none of the relapsed patients had long-term survival. The recurrence mainly occurred at the very early stage (53%), and none of patients with recurrence at the very early stage had long-term survival. The recurrence occurred at early stage and late stage accounted for 34% and 14% respectively, and the 5-year OS rates of patients with recurrence at early stage and late stage were 11.44% and 60.00% respectively. The sites of recurrence were mainly bone marrow alone (83%), and the 5-year OS of patients with recurrence at bone marrow alone was 9.23%. The recurrence in bone marrow and outside bone marrow accounted for 11%, and the 5-year OS of patients with recurrence in both bone marrow and outside bone marrow was 25.00%. The recurrence only outside bone marrow accounted for 6%, and the 5-year OS of patients with recurrence only outside bone marrow was 100%. The recurrence rate in patients with T-cell ALL was 9.5%, and none of the relapsed patients had long-term survival. The recurrence rate in patients with B-cell ALL was 14.3%, and the 5-year OS of the relapsed patients was 15.52%. Conclusions After treatment with the CCLG-ALL2008 protocol, a relatively high recurrence rate is observed in children with high-risk ALL. Positive MLL and positive BCR/ABL are high-risk factors for recurrence. The recurrence rate is not significantly correlated with immunophenotype. A very low survival rate is seen in children whose recurrence have the following features: at early stage, only in bone marrow, T-cell ALL, and abnormal BCR/ABL and MLL.
Objective To evaluate the effectiveness and the practicability of the Acute Lymphoblastic Leukemia Berlin-Frankfurt-Münster 95 (ALL-BFM 95) protocol in treating childhood high-risk acute lymphoblastic leukemia (HR-ALL). Methods A retrospective analysis of 47 children with newly diagnosed HR-ALL between July 2003 and August 2013 was performed. These children were treated by the ALL-BFM 95 protocol. Survival was evaluated by Kaplan Meier analysis and Log-Rank test. Results Relapse-related death occurred in 12 of 47 patients (26%), and 5 of 47 patients (11%) were treatment-related mortality. Five-year probability of event-free-survival (pEFS) was 62%. Children with hematopoietic stem cell transplantation (HSCT) after chemotherapy achieved significantly better pEFS than those with chemotherapy alone (77% vs 52%; P=0.035). The patients who were only poor responders to prednisone had a better outcome (5-year pEFS 80%) than the Days 15 and 33 bone marrow M3 subgroups (5- year pEFS 60% and 0 respectively). Conclusions ALL-BFM 95 protocol can improve the outcome of children with high-risk ALL. The major cause of death is attributed to relapse. Chemotherapy plus HSCT can produce a better outcome than chemotherapy alone. The Days 15 and 33 bone marrow M3 subgroups have a poor prognosis.
Objective To evaluate the efficiency of one-step multiplex RT-PCR for identifying four common fusion transcripts (TEL/AML1, E2A/PBX1, MLL/AF4 and BCR/ABL) in children with acute lymphoblastic leukemia (ALL). Methods Total RNA was extracted from bone marrow samples of 76 children who were newly diagnosed with ALL between January 2003 and December 2010. These RNAs were analyzed for TEL/AML1, E2A/PBX1, MLL/AF4 and BCR/ABL by one-step multiplex RT-PCR or common nested-multiplex PCR. The PCR products were confirmed by DNA sequencing. Results TEL/AML1 was found in 12 cases (the length of products was 298 bp in 9 cases and 259 bp in 3 cases), E2A/PBX1 was found in 3 cases (the length of products was 373 bp), BCR/ABL was found in 1 case (the length of products was 2 124 bp), and MLL/AF4 was found in 7 cases (the length of products was 427 bp in 1 case and 673 bp in 6 cases) using one-step multiplex RT-PCR combined with DNA sequencing. The results were consistent with those using common nested-multiplex PCR. Conclusions One-step multiplex RT-PCR may be another alternative for detection of common fusion transcripts in children with ALL.
Objective To explore the effects of blood transfusion on the vital signs and heart function in preterm infants with anemia. Methods A total of 40 anemic preterm infants with gestational age less than 34 weeks who accepted blood transfusion one week after birth were enrolled for a prospective cohort study. Left ventricular ejection fraction (LVEF), fractional shortening (FS), stroke volume (SV), and cardiac output (CO) were determined with portable ultrasonic equipment before blood transfusion and within 24 hours after blood transfusion. Apnea was detected and the times of apnea were recorded within 24 hours before and after blood transfusion. The resting body temperature and blood pressure were also determined before and after blood transfusion. Additionally the resting heart rate, respiratory rate, and transcutaneous oxygen saturation were recorded within 4 hours before and after blood transfusion. Results The heart rate and respiratory rate decreased significantly within 4 hours after blood transfusion (P<0.05). Four infants had apnea within 24 hours before blood transfusion, and nobody had apnea within 24 hours after blood transfusion. The systolic pressure, diastolic pressure, mean arterial pressure, and body temperature showed no significant changes after blood transfusion (P>0.05), and the LVEF, SV, CO, and FS showed no significant changes after blood transfusion as well (P>0.05). Conclusions Blood transfusion can improve the clinical symptoms and shows no significant effect on the heart function in preterm infants with anemia.
Objective To investigate the risk factors for early disseminated intravascular coagulation (DIC) in neonates with sepsis. Methods A retrospective clinical study was performed on 100 neonates with a confirmed diagnosis of sepsis between 2012 and 2013. The children were classified into normal coagulation group, non-overt DIC group (early DIC group), and overt DIC group (late DIC group) based on the ISTH overt DIC scoring system. The clinical manifestations and risk factors were analyzed statistically. Results Early DIC occurred in 44 (44%) cases in the 100 neonates with sepsis. The incidence of sclerema showed significant differences between the three groups (P<0.05). Asphyxia, bleeding, and Gram-negative bacterial infection were independent risk factors for early DIC. Conclusions Coagulation function should be actively monitored and early intervention measures should be taken for neonates with asphyxia, bleeding, and Gram-negative bacterial infection to prevent early DIC from progressing to late DIC.
Objective To explore the clinical efficacy of high-frequency oscillatory ventilation (HFOV) combined with pulmonary surfactant (PS) in the treatment of neonatal pulmonary hemorrhage (NPH). Methods A total of 122 neonates diagnosed with NPH between January 2010 and June 2014 were enrolled. After being stratified by gestational age, the neonates were randomly divided into treatment (HFOV+PS) and control (HFOV alone) groups (n=61 each). Both groups were treated with HFOV after the onset of NPH. After 2-4 hours of HFOV treatment, the treatment group received PS via intratracheal injections, followed by continuous use of HFOV. Dynamic changes in the blood gas, oxygenation index (OI), and PaO2/FiO2 (P/F) values of the neonates were determined before HFOV treatment and after 6, 12, and 24 hours of HFOV treatment. The time to hemostasis, duration of ventilation, incidence of complications, and cure rate were compared between groups. Results After 6, 12, and 24 hours of HFOV treatment, the treatment group had significantly improved PaO2, PaCO2, O/I, and P/F values compared with the control group (P<0.05). The time to hemostasis and the duration of ventilation were significantly shorter in the treatment group than in the control group (P<0.01), and the incidence of complications was lower in the former than in the latter (P<0.05). There was no significant difference in the cure rate between the treatment (87%) and control (82%) groups (P>0.05). Conclusions HFOV combined with PS is an effective treatment to improve oxygenation, shorten the time to hemostasis and the duration of ventilation, and reduce the incidence of complications in neonates with NPH. However, the dual therapy is unable to reduce the mortality of neonates compared with HFOV monotherapy.
Objective To investigate the survival quality of infants conceived by in vitro fertilization (IVF) and to identify the factors that cause birth defects and neonatal complications in IVF infants. Methods The study included 150 IVF infants (IVF group) and 200 naturally conceived infants (control group). Indicators such as birth situation, gestational disease, birth defects, and neonatal complications were compared between groups. The influencing factors for birth defects and neonatal complications were analyzed by non-conditional logistic regression analysis. Results Compared with the control group, the IVF group had increased incidences of twin pregnancy and low birth weight (P<0.01) but decreased average birth weight (P<0.05). In the IVF group, the mother's age was elder, with higher incidence of cesarean section, premature rupture of membranes, and pregnancy complications, as compared with the control group (P<0.05). There was no significant difference in the incidence of birth defects between the two groups (P>0.05). The IVF group had higher incidence rates of low birth weight and neonatal scleroderma (P<0.05), with a longer hospital stay (P<0.01), as compared with the control group. The non-conditional logistic regression analysis indicated that IVF, prematurity, twin pregnancy, and pregnancy complications were risk factors for low birth weight (P<0.05). Conclusions There is no significant difference in the incidence of birth defects between IVF and naturally conceived infants. However, IVF infants have higher incidences of twin pregnancy and low birth weight, with a longer hospital stay, as compared with naturally conceived infants. Natural conceiving, avoiding prematurity, twin pregnancy, and pregnancy complications will reduce the incidence of low birth weight.
Objective To screen the coding region of melanocortin-4 receptor gene (MC4R) for mutations in children, analyze the association of the identified variants with obesity-related phenotypes, and predict the potential functions of the identified variants. Methods A case-control study was conducted in 160 severely obese children and 100 normal-weight controls, all aged 7-18 years. Their anthropometric data were collected and blood tests were performed. The coding region of MC4R gene was screened by polymerase chain reaction (PCR), single strand conformation polymorphism and sequencing, and the potential functions of the identified variants were predicted by related online databases. Results Three heterozygous missense mutations were identified in obese children (Val95Ile, Val166Ile and Val179Ala), and one heterozygous missense mutation was found in controls (Met218Thr). Val103Ile variant was found to be carried by seven subjects in the obese group and six in the control group (P>0.05). Val179Ala was a newly identified heterozygous mutation. No significant differences in BMI, weight, waist circumstance, hip circumstance, serum lipid parameters, fasting glucose, and body fat percentage were found between Val95Ile, Val166Ile or Val179Ala mutation carriers and non-carriers in obese children. The function prediction of the variants showed that all the five identified variants influenced the protein function. Conclusions Five variants were identified in the coding region of MC4R gene, among which Val179Ala was newly identified. All the five variants might influence the protein function as evidenced by online prediction.
Fanconi-Bickel syndrome (FBS, OMIM 227810), a rare autosomal recessive disorder of carbohydrate metabolism, is caused by SLC2A2 (GLUT2) mutations. The study reported 3 cases of FBS who were confirmly diagnosed by SLC2A2 gene analysis. The three patients showed typical features like glycogen storage disease and proximal renal tubular nephropathy. Homozygous splice-site mutation IVS8+5G>C (c.1068+5 G>C) was found in patient A and homozygous nonsense mutation c.1194T>A (p.Tyr398X) in patient B. Patient C harboured a missense mutation c.380C>A (p.Ala127Asp) and a de novo insertion c.970dupT (p.324TyrfsX392) which was not inherited from her parents. Four mutations were identified in the 3 Chinese FBS patients. Except IVS8+5G>C mutation, the other 3 mutations were novel in Chinese population. To the best of our knowledge, patient C may be the first FBS case worldwide with de novo mutation.
The clinical data of a patient with megalencephalic leukoencephalopathy (MLC) with subcortical cysts and her parents were collected. MLC1 gene mutation was detected by polymerase chain reaction and direct DNA sequencing. The patient presented with motor developmental delay and giant skull, and brain magnetic resonance imaging showed diffuse white matter swelling accompanied by subcortical cysts in bilateral frontal and parietal lobes. Gene sequencing identified two heterozygous mutations of MLC1, including missense mutation in exon 3 (c.217G>A, p.Gly73Arg) and splice site mutation in intron 9 (c.772-1G>C in IVS9-1). The patient's parents both had heterozygous mutation c.772-1G>C in IVS9-1 with normal phenotype. It can be presumed that c.772-1G>C in IVS9-1 comes from the parents, and c.217G>A (p.Gly73Arg) is a de novo mutation.
Objective To compare the clinical and pathological features between children with various genotypes of hepatitis B virus-associated glomerulonephritis (HBV-GN). Methods Forty-one children with HBVGN concurrently undergoing liver and renal biopsy were randomly selected. Serum specimens were collected for genotyping and hepatitis B virus (HBV) cccDNA assay. The clinical, pathological, and HBV cccDNA differences between HBV-GN children of various genotypes were analyzed. Results Among the 41 HBV-GN children, 29 (71%) were genotype C, 10 (24%) were genotype B, and 2 (5%) were genotype B/C. The incidence rates of hematuria, albuminuria, complement 3 decrease, alanine transaminase increase, and renal insufficiency in the genotype C group were significantly higher than those in the genotype B group (P<0.05). Similarly, the HBV cccDNA positive rate was significantly higher in the genotype C group than that in the genotype B group. No difference was observed in the distribution of pathological types of renal tissues betwee the two geonotype groups. There were no significant differences in the degrees of hepatic inflammation and fibrosis between the two groups. Conclusions Mainly genotypes C and B occur in children with HBV-GN and the former genotype is dominant. The clinical symptoms of patients with genotype C are more serious than those with genotype B. However, there is no difference in the pathological features between them.
Objective 25-Hydroxyvitamin D3 [25(OH)D3] is the main product of vitamin D and can reflect the absolute concentration of active vitamin D in the body. This study examined serum 25(OH)D3 levels in children with juvenile idiopathic arthritis (JIA) in order to explore the association of vitamin D concentrations with the pathogenesis and disease activity of JIA. Methods Serum samples were collected from 53 children confirmed as having JIA between January 2013 and March 2014, as well as 106 healthy children (control group) who underwent physical examination in the same period. Serum concentrations of 25(OH)D3 were measured using ELISA and compared between the cases and healthy controls. The association of serum 25(OH)D3 levels with JIA subtypes, ACR Pediatric 30 Score, peripheral blood C-reactive protein (CRP), and erythrocyte sedimentation rate (ESR) were analyzed in children with JIA. Results Compared with the control group, the JIA group had significantly reduced serum 25(OH)D3 levels (median: 42.6 nmol/L vs 49.9 nmol/L; P<0.01). The percentage of subjects with severe deficiency of vitamin D in the JIA group was significantly higher than that in the control group (17.0% vs 6.6%; P<0.05). Serum 25(OH)D3 showed no significant correlations with JIA subtypes, ACR Pediatric 30 Score, CRP, and ESR in children with JIA. Conclusions Vitamin D concentrations are significantly decreased in children with JIA. Decreased vitamin D concentrations may be associated with the pathogenesis of JIA. However, vitamin D concentrations may have no correlations with JIA subtypes, disease severity, and disease activity.
Objective To explore the factors influencing cognitive functions in patients with childhood and adolescence-onset schizophrenia. Methods The clinical data of 78 patients with childhood and adolescence-onset schizophrenia who met with the criteria of ICD-10 for schizophrenia were retrospectively reviewed. The cognitive functions were evaluated by the Chinese Wechsler Intelligence Scale for Children (C-WISC), the Wisconsin Card Sorting Test (WCST), digit span backward and P300. The clinical symptoms were evaluated by the Positive and Negative Syndrome Scale (PANSS). Results The patients with a lower education level or earlier onset of age had a longer P3 latency at the P300Fz area. The patients with a higher parental education level had higher scores of full intelligence quotient (FIQ), verbal intelligence quotient (VIQ), performance intelligence quotient (PIQ), conceptual level and completed categories of WCST and backward numeric order reciting. The patients with higher PANSS negative subscale scores had lower scores of FIQ, VIQ, PIQ, completed categories and conceptual level of WCST and backward numeric order reciting. The patients with a longer stabilization time had higher backward numeric order reciting scores. Conclusions The severity of negative symptoms of the patients and the educational level of their parents are major factors influencing cognitive functions in patients with childhood and adolescence-onset schizophrenia.
Objective To evaluate the short- and medium-term efficacy, complications, and anti-coagulation therapies related to transcatheter closure (TCC) of coronary artery fistula (CAF) in children. Methods We conducted a retrospective review of the medical records of 12 children with CAF who underwent TCC between January 2006 and January 2014, focusing on details such as preoperative, radiographic, and postoperative follow-up data, to record closure methods for CAF, anti-coagulation therapies, postoperative complications, and results of auxiliary examinations. Results Among the 12 cases who underwent successful TCC and whose age was 1-158 months, four patients had proximal/medium-sized CAF, five had proximal/large CAF, and three had distal/medium-sized CAF. The mean period of postoperative follow-up was 3.5±2.4 years. Eleven patients took aspirin for 6 months post closure, and one took it for 18 months. Neither coronary thrombosis nor interventional complications were found. Left ventricular ejection fraction, cardiothoracic ratio, pulmonary artery pressure, and the diameters of coronary artery lesions decreased post TCC. Conclusions TCC is feasible and safe in proximal and distal/medium-sized CAF patients. Postoperative anticoagulation with aspirin may prevent short- and medium-term thrombosis, but treatment course and safety need to be investigated by further follow-ups.
Objective To study the protocol of construction of the mutation E292V and M723I of hABCA3 gene associated with neonatal respiratory distress syndrome, as well as their eukaryotic green fluorescent protein expression rectors, and to examine the expression of mutation proteins in human lung carcinoma epithelial cells (A549). Methods Site-directed mutagenesis method based on overlap extension PCR was used to introduce mutations in the two sites which were E292V and M723I in the ABCA3. The PCR fragments were subcloned to PEGFP-C2 vectors to construct the eukaryotic green fluorescent protein expression rectors. A549 cells were transiently transfected with the recombinants using Lipofectamine 2000 and the transfection efficiency was confirmed through GFP signal. The expression and location of recombinants were detected by FV1000 laser scanning microscope. Results Direct sequence analysis confirmed an A to T transition at position 875 in E292V and a G to A transition at position 2169 in M723I. Recombinants were transfected to A549 cells and both wild type and mutant ABCA3 proteins were expressed in the cytoplasm. Conclusions The eukaryotic green fluorescent protein expression rectors of wild type and mutant ABCA3 gene were constructed and they were successfully expressed in A549 cells. This experiment provides a basis for subsequent research.
Objective To observe changes in the expression of autophagy-related proteins, Beclin-1 and LC3, in the hippocampal tissue of neonatal rats with hypoxic-ischemic brain damage (HIBD) at different time points, and to investigate the effect of rapamycin (Ra) on the expression of the above two proteins. Methods A total of 108 7-dayold Sprague-Dawley rats were randomly divided into sham, HIBD, and Ra groups (n=36 each). The HIBD model was established using the modified Rice method. For sham rats, only the left common carotid artery was separated without ligation or hypoxic treatment. For Ra-treated rats, 0.5 mg/kg Ra was administered by an intraperitoneal injection 1 hour before model establishment. The rats were anesthetized and sacrificed to collect brain tissues at 0, 6, 12, 24, 48, and 72 hours after model establishment. Changes in the expression of Beclin-1 and LC3 proteins in rat hippocampus were examined by Western blot. Results The expression level of Beclin-1 in HIBD rats began to increase at 0 hour, peaked at 24 hours, and then declined thereafter, similar as those of Beclin-1 and LC3-II in Ra-treated rats. The expression level of LC3-II in HIBD rats began to increase at 0 hour, peaked at 12 hours, and then declined thereafter. At all time points, both Beclin-1 and LC3-II expression levels were significantly higher in HIBD and Ra-treated rats than in sham rats (P<0.05); except LC3-II at 12 hours, Beclin-1 and LC3-II expression levels were significantly higher in Ra-treated rats than in HIBD rats (P<0.05). Conclusions Hypoxia-ischemia activates autophagy in rat hippocampal cells, while Ra enhances the expression process of autophagy.