Primary repair of esophageal atresia gross type C via thoracoscopic magnetic compression anastomosis: A case report.

BACKGROUND: Esophageal atresia (EA) is a life-threatening congenital malformation in newborns, and the traditional repair approaches pose technical challenges and are extremely invasive. Therefore, surgeons have been actively investigating new minimally invasive techniques to address this issue. Magnetic compression anastomosis has been reported in several studies for its potential in repairing EA. In this paper, the primary repair of EA with magnetic compression anastomosis under thoracoscopy was reported. CASE SUMMARY: A full-term male weighing 3500 g was diagnosed with EA gross type C. The magnetic devices used in this procedure consisted of two magnetic rings and several catheters. Tracheoesophageal fistula ligation and two purse strings were performed. The magnetic compression anastomosis was then completed thoracoscopically. After the primary repair, no additional operation was conducted. A patent anastomosis was observed on the 15th day postoperatively, and the magnets were removed on the 23rd day. No leakage existed when the transoral feeding started. CONCLUSION: Thoracoscopic magnetic compression anastomosis may be a promising minimally invasive approach for repairing EA.

Neonatal isovaleric acidemia in China: A case report and review of literature.

BACKGROUND: Isovaleric acidemia (IVA) is a rare autosomal recessive inherited organic acidemia caused by a genetic deficiency of isovaleryl-CoA dehydrogenase (IVD). Its morbidity is low, but mortality is high. There is no effective cure for this disease. Early identification of IVA using clinical features can significantly slow disease progression and reduce mortality. Here we report a Chinese neonate with two mutations of IVD and share valuable information on this disease. CASE SUMMARY: A 12-day-old male neonate with "poor response for 1 d and repeated convulsions accompanied by high muscle tension for 6 h" was hospitalized. The patient was the first child of nonconsanguineous ethnic Chinese parents. He was delivered by cesarean section due to breech position at 39 + 1 wk of gestation with a birth weight of 3.27 kg. Initially, he suffered from dyspnea and rhinobyon, and at 10 d after birth the patient suddenly developed poor feeding, low response, lethargy and seizures. Organic acid analysis of blood and urine by tandem mass spectrometry and gas chromatography mass spectrometry showed extremely high concentrations of isovaleryl glycine. The patient had an acute episode of IVA causing severe metabolic stress and eventually died. CONCLUSION: A new case of an IVA patient carrying c.1193G>A (p.Arg398Gln) and c.1208A>G (p.Try403Cys) mutations is reported in China.

[A comparative analysis of the efficacy of two vitamin D supplementation regimens in preterm infants: a prospective randomized controlled study].

OBJECTIVE: To study the effect of different vitamin D supplementation regimens on the nutritional status of vitamin D on day 28 after birth in preterm infants with a gestational age of <34 weeks. METHODS: A total of 59 preterm infants with a gestational age of <34 weeks who were born from October 2018 to October 2019 were enrolled and divided into an observation group with 30 infants and a control group with 29 infants. The infants in the observation group received a single-dose intramuscular injection of vitamin D3 (10 000 IU/kg), while those in the control group received oral vitamin D3 drops (900 IU/d) for 25 days. Venous blood samples were collected within 48 hours after birth (before vitamin D3 supplementation) and on day 28 after birth to measure the serum 25-hydroxyvitamin D [25(OH)D] level. RESULTS: Within 48 hours after birth, the prevalence rate of vitamin D deficiency (≤15 ng/mL) was 78% among the 59 preterm infants. There were no significant differences in the serum 25(OH)D level and the prevalence rate of vitamin D deficiency between the two groups (P>0.05). Compared with the control group on day 28 after birth, the observation group had a significantly higher serum 25(OH)D level (P<0.05) and a significantly lower prevalence rate of vitamin D deficiency (P<0.05). There were no cases of vitamin D overdose or poisoning. CONCLUSIONS: In preterm infants with a gestational age of <34 weeks, single-dose intramuscular injection of 10 000 IU/kg vitamin D3 can significantly increase serum 25(OH)D level on day 28 after birth and safely and effectively reduce the prevalence rate of vitamin D deficiency.

[Sedative effect of intranasal midazolam in neonates undergoing magnetic resonance imaging: a prospective single-blind randomized controlled study].

OBJECTIVE: To compare intranasal midazolam and intramuscular phenobarbital sodium for their sedative effect in neonates undergoing magnetic resonance imaging (MRI). METHODS: A total of 70 neonates who underwent cranial MRI from September 2017 to March 2019 were randomized into an observation group and a control group, with 35 cases in each group. The observation group received intranasal drops of midazolam (0.3 mg/kg), and the control group received intramuscular injection of phenobarbital sodium (10 mg/kg). The sedation status of the neonates was evaluated using the Ramsay Sedation Scale. Meanwhile, the two groups were compared for the success rate of MRI procedure and incidence of adverse reactions. RESULTS: In the observation group, the sedation score was the highest at 20 minutes post administration, then was gradually decreasing, and decreased to the lowest level at 70 minutes post administration. In the control group, the sedation score was the lowest at 10 minutes post administration, then was gradually increasing, and increased to the highest level at 40 minutes and 50 minutes post administration, followed by a gradual decrease. Comparison of the sedation score at each time period suggested that the sedation score was significantly higher in the observation group than in the control group within 40 minutes post administration (P<0.05), while there were no significant differences between the two groups in the sedation score after 40 minutes post administration (P>0.05). The success rate of MRI procedure was significantly higher in the observation group than in the control group (89% vs 69%, P<0.05). There was no significant difference between the two groups in the incidence of adverse reactions (P>0.05). CONCLUSIONS: Intranasal midazolam is superior to intramuscular phenobarbital sodium in the sedative effect in neonates undergoing MRI, with the benefits of being fast, convenient, safe, and effective.

[Influence of acute pancreatitis in pregnancy on pregnancy outcomes and neonates].

OBJECTIVE: To study the influence of acute pancreatitis in pregnancy (APIP) on pregnancy outcomes and neonates. METHODS: A retrospective analysis was performed for 33 APIP patients and 31 neonates born alive. RESULTS: Of the 33 APIP patients, 26 (79%) developed APIP in the late pregnancy. Fourteen (45%) patients had hyperlipidemic APIP, 13 (42%) had biliary APIP, and 4 (13%) had other types of APIP. According to the severity, 22 (67%) were mild APIP, 5 (15%) were moderate APIP, and 6 were severe APIP. None of the 33 APIP patients died. Among the 20 patients with term delivery, 11 underwent termination of pregnancy; among the 10 patients with preterm delivery, 9 underwent termination of pregnancy; two patients experienced intrauterine fetal death, and one experienced abortion during the second trimester. Among the 31 neonates born alive (two of them were twins), 1 (3%) died, 12 (39%) experienced neonatal hyperbilirubinemia, 8 (26%) had neonatal hypoglycemia, 6 (19%) had neonatal respiratory distress syndrome, 5 (16%) experienced infectious diseases, and 2 (6%) experienced intracranial hemorrhage. The hyperlipidemic APIP group had a higher percentage of patients undergoing termination of pregnancy than the biliary APIP and other types of APIP groups (P<0.05). The incidence rate of preterm infants in the moderate APIP was higher than in the mild and severe APIP groups (P<0.05). The mean birth weights of neonates were the lowest in the moderate APIP group. The incidence rates of neonatal respiratory distress syndrome, intracranial hemorrhage, and infectious disease were the lowest in the mild APIP group (P<0.05). CONCLUSIONS: APIP can lead to adverse pregnancy outcomes and neonatal diseases, which are associated with the severity of pancreatitis.

[The Function of Potassium Channel in KCNQ2 G271V Mutants of Benign Familial Neonatal Convulsions].

OBJECTIVE: To determine the function of potassium channel in KCNQ2 G271V mutants of benign familial neonatal convulsions. METHODS: HEK293 cells were transfected with pcDNA3-WT-KCNQ2 and / or pcDNA3-G271V-KCNQ2 and pcDNA3-WT-KCNQ3. The potassium channel function of G271V mutants was assessed using the whole cell patch clamp technique. RESULTS: G271V mutants did not show currents in the transfected HEK cells, inducing large depolarizing shift of the conductance voltage relationship and slowing down the current activation kinetics. The required current density was (2.47±0.41) pA/pF (n=12) for the expression of G271V, and whereas (20.53±2.51) pA/pF (n=10,P<0.001) for Kv7.2. G271V mutants abolished currents in the homomeric channel. Kv7.2/Kv7.3 induced robust current was (123.68±15.21) pA/pF (n=15) and Kv7.2/G271V/Kv7.3 (42.71±6.27) pA/pF (n=10), G271V/Kv7.3 induced almost no current (3.74±0.76) pA/pF (n=10,P<0.05), resulting in about 50% reduction of currents in Kv7.2/G271V/Kv7.3 in the heteromultimeric condition. CONCLUSIONS: The G271V channel fails to open potassium currents in response to depolarization, indicating a more severe functional defect of the Kv7 potassium channel.

[Site-directed mutagenesis and protein expression of ABCA3 gene in A549 cells].

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.

Semi-quantitative assessment of brain maturation by conventional magnetic resonance imaging in neonates with clinically mild hypoxic-ischemic encephalopathy.

BACKGROUND: Mild hypoxic-ischemic encephalopathy (HIE) injury is becoming the major type in neonatal brain diseases. The aim of this study was to assess brain maturation in mild HIE neonatal brains using total maturation score (TMS) based on conventional magnetic resonance imaging (MRI). METHODS: Totally, 45 neonates with clinically mild HIE and 45 matched control neonates were enrolled. Gestated age, birth weight, age after birth and postmenstrual age at magnetic resonance (MR) scan were homogenous in the two groups. According to MR findings, mild HIE neonates were divided into three subgroups: Pattern I, neonates with normal MR appearance; Pattern II, preterm neonates with abnormal MR appearance; Pattern III, full-term neonates with abnormal MR appearance. TMS and its parameters, progressive myelination (M), cortical infolding (C), involution of germinal matrix tissue (G), and glial cell migration bands (B), were employed to assess brain maturation and compare difference between HIE and control groups. RESULTS: The mean of TMS was significantly lower in mild HIE group than it in the control group (mean ± standard deviation [SD] 11.62 ± 1.53 vs. 12.36 ± 1.26, P < 0.001). In four parameters of TMS scores, the M and C scores were significantly lower in mild HIE group. Of the three patterns of mild HIE, Pattern I (10 cases) showed no significant difference of TMS compared with control neonates, while Pattern II (22 cases), III (13 cases) all had significantly decreased TMS than control neonates (mean ± SD 10.56 ± 0.93 vs. 11.48 ± 0.55, P < 0.05; 12.59 ± 1.28 vs. 13.25 ± 1.29, P < 0.05). It was M, C, and GM scores that significantly decreased in Pattern II, while for Pattern III, only C score significantly decreased. CONCLUSIONS: The TMS system, based on conventional MRI, is an effective method to detect delayed brain maturation in clinically mild HIE. The conventional MRI can reveal the different retardations in subtle structures and development processes among the different patterns of mild HIE.

Hyperbaric oxygenation reduces long-term brain injury and ameliorates behavioral function by suppression of apoptosis in a rat model of neonatal hypoxia-ischemia.

Neonatal hypoxia-ischemia (HI) produces neurodegeneration and brain injury, and leads to behavioral and cognitive dysfunction. Hyperbaric oxygen (HBO) treatment may potentially be neuroprotective in HI injury. The aim of this study was to examine any neuroprotection by HBO treatment on long-term neurological function in the rat model of neontatal HI. Seven-day-old rats were subjected to HI or sham surgery. HBO treatment was administered (2.5 ATA for 90 min) 1h after hypoxia exposure. Sensorimotor (grip test and rota-rod) and cognitive tests (inhibitory avoidance and Morris water maze) were performed at postnatal day 28 to day 60. The extent of brain damage was determined by histological evaluation. Apoptosis, caspase-3 and apoptosis inducing factor (AIF) expression were assessed by immunohistochemistry 12, 24, and 48 h after HI. HI-treated animals had significantly worse sensorimotor and cognitive performances than those in the Sham group. HBO treatment led to significant improvements in neurobehavioral functions compared to the HI group, especially for cognitive performances. Morphological evaluation revealed a remarkable recovery of brain injury in the HBO group. Furthermore, the improvements in neurobehavioral impairments were correlated with the reduction in lesion size of the hippocampus and cerebral cortex. The proportion of apoptotic cells significantly increased with time after HI, and HBO significantly inhibited apoptotic cell death. The proportion of caspase-3 positive cells and nuclear AIF translocation increased and peaked at 24h after HI injury. HBO-treated rats showed decreased expression of these proteins compared to HI-treated animals. In conclusion, our results suggested that HBO treatment was effective in promoting long-term functional and histological recovery against neonatal HI brain injury. HBO-induced neuroprotection was associated with suppression of apoptosis by inhibiting caspase-3 and AIF-mediated pathways. Further studies evaluating its associated molecular and cellular mechanism are needed.

Clinical and pathological features of a neonate with autosomal recessive polycystic kidney disease caused by a nonsense PKHD1 mutation.

BACKGROUND: Autosomal recessive polycystic kidney disease (ARPKD) is one of the most common hereditary nephropathies in childhood. We report a neonate with ARPKD presenting with oligohydramnios, enlargement and increased echogenicity of both kidneys shown by antenatal sonograms after a 29-week gestation and died within the first few hours of life. METHODS: The neonate was investigated pathologically post-mortem. PCR-DNA direct sequencing was performed to detect the exons of the PKHD1 gene for mutation analysis. RESULTS: Autopsy findings of the kidney and liver confirmed the diagnostic hypothesis. PKHD1 mutation analysis revealed that there was a homozygous nonsense mutation c.9319C>T (p.R3107X), which was found to be pathogenic, in exon 58 in the neonate. CONCLUSIONS: The recurrence of PKHD1 mutation c.9319C>T (p.R3107X) in the ARPKD population might be a good evidence that it is disease associated. Given the limitations of antenatal ultrasound, PKHD1 mutation analysis is helpful for accurate genetic counseling and early prenatal diagnosis.

[Detection of genetic defect within ABCA3 from newborns with respiratory distress syndrome].

OBJECTIVE: To detect possible relationship between genetic defect within the gene encoding member A3 of the ATP Binding Cassette family (ABCA3) and neonatal respiratory distress syndrome (NRDS), thus to understand the genetic mechanisms of NRDS in Han ethnic group. METHOD: The clinical data of 11 cases with NRDS hospitalized in neonatal intensive care unit was investigated. Blood samples were collected from 11 cases with NRDS and 97 unassociated normal individuals. Polymerase chain reaction (PCR) and DNA direct sequencing were performed to screen all exons and their flanking introns of ABCA3 gene for mutation analysis in 11 cases with NRDS. If a new missense variation was identified, single strand conformation polymorphism analysis was performed in 97 healthy controls. Lung tissue sample from a case who died 12 hours after birth was examined with light microscopy and electron microscopy. RESULT: Three missense genetic variants in exons, which include c. 2169 G > A (p.M723I), c. 1010 T > G (p.V337G), c. 4972 A > G (p.S1658G), one splice junction site variation (Exon 30 + 2 T/G), several unreported polymorphism sites [213 C > T(p.F71F), exon 21 + 34C/T] and reported polymorphism site (p.F353F) were identified on ABCA3 gene coding region in 11 case. The homozygous variation (c.2169G > A), which was in exon 17 and causes an M723I amino acid change, was found in the case who died 13 hours after birth, but not detected in 97 controls, indicating that this variation is indeed a mutation and not a polymorphism. In the case carrying c.2169G > A, ultrastructural examination of the alveolar type II cells with electron microscopy demonstrated abnormally small and dense lamellar body with eccentrically distributed electron dense substance. CONCLUSION: Genetic variants within ABCA3 may be the genetic cause of or a contributor to some unexplained refractory NRDS. Identification of ABCA3 genetic variant in NRDS infants is important to establish appropriate management and evaluation of treatment options, as well as to offer genetic counseling and prenatal diagnosis.

Site-directed mutagenesis of neonatal convulsions associated KCNQ2 gene and its protein expression.

OBJECTIVE: To study the protocol of construction of a KCNQ2-c.812G>T mutant and its eukaryotic expression vector, the c.812G>T (p.G271V) mutation, which was detected in a Chinese pedigree of benign familial infantile convulsions (BFIC), and to examine the expression of mutant protein in human embyonic kidney (HEK) 293 cells. METHODS: A KCNQ2 mutation c.812G>T was engineered on KCNQ2 cDNAs cloned into pcDNA3.0 by sequence overlap extension PCR and restriction enzymes. HEK293 cells were co-transfected with pRK5-GFP and KCNQ2 plasmid (the wild type or mutant) using lipofectamine and then subjected to confocal microscopy. The transfected cells were immunostained to visualize the intracellular expression of the mutant molecules. RESULTS: Direct sequence analysis revealed a G to T transition at position 812. The c.812G>T mutation was correctly combined to eukaryotic expressive vector pcDNA3.0 and expressed in HEK293 cells. Immunostaining of transfected cells showed the expression of both the wild type and mutant molecules on the plasma membrane, which suggested that the c.812G>T mutation at the pore forming region of KCNQ2 channel did not impair normal protein expression in HEK293 cells. CONCLUSIONS: Successful construction of mutant KCNQ2 eukaryotic expression vector and expression of KCNQ2 protein in HEK293 cells provide a basis for further study on the functional effects of convulsion-causing KCNQ2 mutations and for understanding the molecular pathogenesis of epilepsy.

[Site-directed mutagenesis and protein expression of KCNQ2 gene associated with neonatal convulsions].

OBJECTIVE: To study the protocol of construction of a KCNQ2-c.812G>T mutant and it's eukaryotic expression vector, the c.812G>T (p.G271V) mutation which was detected in a Chinese pedigree of benign familial infantile convulsions, and to examine the expression of mutant protein in human embyonic kidney (HEK) 293 cells. METHODS: A KCNQ2 mutation c.812G>T was engineered on KCNQ2 cDNAs cloned into pcDNA3.0 by sequence overlap extension PCR and restriction enzymes. HEK293 cells were co-transfected with pRK5-GFP and KCNQ2 plasmid (the wild type or mutant) using lipofectamine and then subjected to confocal microscopy. The transfected cells were immunostained to visualize the intracellular expression of the mutant molecules. RESULTS: Direct sequence analysis revealed a G to T transition at position 812. The c.812G>T mutation was correctly combined to eukaryotic expressive vector pcDNA3.0 and expressed in HEK293 cells. Immunostaining of transfected cells showed the expression of both the wild type and mutant molecules on the plasma membrane, which suggested that the c.812G>T mutation at the pore forming region of KCNQ2 channel did not impair normal protein expression in HEK293 cells. CONCLUSIONS: Successful construction of mutant KCNQ2 eukaryotic expression vector and expression of KCNQ2 protein in HEK293 cells provide a basis for further study on the functional effects of convulsion-causing KCNQ2 mutations and for understanding the molecular pathogenesis of epilepsy.

[Effect of inhibitors of phospholipase A(2); on the metastasis potentials of human ovarian cancer cells].

AIM: it is important to find inhibitors for metastasis of ovarian cancer (OC). OC cells (OCC) produce Lysophosphophatidic acid (LPA), which promotes the OC development. Phospholipase A(2); (PLA(2);) is responsible for LPA production. This study is to investigate the effect of PLA(2); inhibitors on the metastasis of OC. METHODS: cell migration and adhesion were measured by Transwell assay. The expression and activation of PLA(2); were detected by Western blot. Invasion into the peritoneal monolayer was detected through ECIS. LPA concentration was measured by mass spectrum. Metastasis was detected through in vivo OC model. RESULTS: (1) LPA promoted the migration and adhesion of SKOV3 in a dose-dependent manner in vitro; (2) iPLA(2); and cPLA(2); expressed highly and activated in SKOV3. (3)AACOCF3 and HELSS significantly inhibited LPA secretion from SKOV3; (4)AACOCF3 and HELSS significantly inhibited the distant metastasis of SKOV3 in mude mice model. CONCLUSION: LPA significantly enhanced the migration, adhesion and invasion of SKOV3. AACOCF3 and HELSS significantly inhibited the LPA secretion, migration and invasion of SKOV3. They also inhibited the distant metastasis of SKOV3 in vivo. Our data suggest AACOCF3 and HELSS may be the potential inhibitors of metastasis of OC.

[Linkage analysis and gene mapping of one Chinese family with benign familial infantile convulsions].

OBJECTIVE: The present study performed linkage analysis and gene mapping to find the possible chromosome locus harboring in one family with benign familial infantile convulsions (BFIC) and investigate the possible molecular pathogenesis of BFIC. METHODS: A four-generation family with BFIC was investigated. The family was genotyped using eight hypervariable microsatellite markers covering four loci: D19S245 and D19S250 for the 19q12-13.1 region, D16S3131 and D16S3133 for the 16p12-q12 region, D2S156 and D2S286 for the 2q24 region, and D20S480 and D20S481 for the 20q13.3 region. Polymorphism fragments were amplified using polymerase chain reaction (PCR) method. PCR products for the markers were subjected to electrophoresis on 8% denatured polyacrylamide gel and silver staining for length judgment of amplification fragment. Linkage analysis was performed by use of MLINK in the LINKAGE computer package. Two-point LOD scores were calculated to estimate the linkage relationship. RESULTS: The two-point LOD scores were less than -2.0 for the genetic markers at chromosomes 19q12-13.1, 16p12-q12 and 2q24 at the recombination rate between 0.000 and 0.01. The two-point LOD scores for D20S481 at the 20q13.3 region were 0.3 and 0.25 at the recombination rate of 0.000 and 0.01, respectively. CONCLUSIONS: There is no evidence that this family with BFIC is linked to one of the following loci: 19q12-13.1, 16p12-q12 and 2q24, but a possible linkage with 20q13.3 region cannot be excluded.

[Gene mutation analysis of a Chinese family of congenital long Q-T syndrome type three].

OBJECTIVE: The congenital long QT syndrome (LQTs) is a hereditary disorder in which most affected family members have delayed ventricular repolarization manifested on the electrocardiogram (ECG) as QT interval prolongation. The disorder is associated with an increased propensity to arrhythmogenic syncope, polymorphous ventricular tachycardia (torsade de pointes), and sudden arrhythmic death. LQTs is due to mutations involving principally the myocyte ion-channels, and this monogenetic disorder has an autosomal inheritance pattern. This study investigated the gene mutation of a Chinese family of LQTs with multiple phenotypes including dilated cardiomyopathy (DCM) and cardiac conduction defects, thus to understand the molecular pathogenesis of the diseases. METHODS: A three-generation Chinese LQTs family with multiple phenotypes was investigated. Blood sample was collected from the 8 family members and 100 unassociated normal individuals. Polymerase chain reaction (PCR)-DNA direct sequencing was performed to screen all exons and their flanking introns of SCN5A gene for mutation analysis. Polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) was used to exclude polymorphism. RESULTS: PCR amplification and subsequent direct sequencing of SCN5A from proband revealed a heterozygous deletion of nine base pairs (CAGAAGCCC) in exon 26, corresponding to the three amino acid residues Gln1507-Lys1508-Pro1509 (QKP). This mutation is localized in the linker region between DIII-DIV of SCN5A. The same mutation was found in another patient (her grandmother) and excluded in the remaining living subjects in this family. This mutation was confirmed using SSCP in 100 unassociated healthy individuals. Similar analysis excluded possible mutations that would lead to amino acid changes in KCNQ1, KCNH2 and LAMIN A/C commonly associated with LQTs and DCM with conduction disorders, no new mutations that would lead to amino acid changes was found. CONCLUSION: The result of the present study suggests that SCN5A mutation delQKP1507-1509 exists in patients with LQTs. The delQKP1507-1509 of SCN5A is a novel mutation in Chinese people. The same mutation was previously reported in a French family with only a single LQTs phenotype. Further studies on functional expression of SCN5A mutation delQKP1507-1509 will be helpful to understand the mechanism of the multiple phenotypes.

[Hyperbaric oxygen improves long-term learning-memory deficits and brain injury in neonatal rat with hypoxia-ischemia brain damage].

OBJECTIVE: To investigate the effect of hyperbaric oxygen (HBO) on long-term learning-memory disabilities and brain injury induced by hypoxia-ischemia in neonatal rat. METHODS: In the study, eighteen rats aged seven days were divid into three groups: (1) sham-operated group (SHAM), (2) hypoxia-ischemia group (HIBD), (3) HBO-treated hypoxia-ischemia group (HIBD + HBO). In hypoxia-ischemia groups, left common carotid artery was ligated permanently on the seventh postnatal day, two hours after the procedure; hypoxia (92% nitrogen and 8% oxygen) was induced for 2 h. In HBO-treated hypoxia-ischemia group, single HBO (2. 5 ATA, 1.5 h) was administered at one hour after the hypoxia period. At the six weeks old, step-down inhibitory avoidance test was used to evaluate the short-term memory of rats. Learning and long-term spatial memory deficits were tested using Morris water maze at eight weeks old of rats. Rats were then perfused and brains removed for macroscopic and microscopic evaluation. The cell density of hippocampus were used to evaluate the degree of brain injure. RESULTS: In HIBD+HBO group, the latency to step down the platform was significantly longer than that of HIBD group (P<0.05); in HIBD+HBO group, the mean latencies to reach the platform was significantly shorter than that of HIBD group (P < 0.05); in HIBD + HBO group, the time spent in the target quadrant was significantly lower than that in HIBD group (P<0.05). Histopathological evaluation demonstrated that HBO also significantly diminished brain injury and decreased the cell loss of hippocampal CA1 region. CONCLUSION: Single HBO (2.5 ATA, 1.5 h) can significantly improve long-term learning-memory deficits and attenuate brain injury in rats with hypoxia-ischemia brain damage.

[A novel mutation in KCNQ2 gene causes benign familial infantile convulsions (BFIC) in a Chinese family].

OBJECTIVE: Benign familial infantile convulsions (BFIC) is a form of idiopathic epileptic syndrome characterized by onset of afebrile seizures between 3 and 12 months of life, Spontaneous remission after several weeks or months, and autosomal dominant mode of inheritance. Previous linkage analysis in western countries defined three susceptible loci on chromosomes 19q12.0-13.1, 16p12-q12, and 2q23-31, but studies performed in several Chinese families with BFIC got negative results of these previously reported loci. The authors investigated the relation of voltage-gated potassium channel gene KCNQ2 to BFIC in a Chinese family and thus to understand the molecular pathogenesis of BFIC. METHODS: A four-generation Chinese BFIC family was investigated. All the affected 17 members had similar pattern of seizures starting from 2 to 6 months of age. In 15 of them, the seizures disappeared spontaneously within the first year of life. The phenotype extended beyond infancy only in two patients. Blood sample was collected from the 41 family members and 75 unassociated normal individuals. Polymerase chain reaction (PCR)-DNA direct sequencing was performed to screen all exons and their flanking introns of KCNQ2 gene for mutation analysis. Polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) was used to ascertain the co-segregation of genotype and phenotype and to exclude polymorphism. RESULTS: PCR amplification and subsequent direct sequencing of KCNQ2 from the DNA of proband revealed a heterozygous guanine to thymine nucleotide exchange (G812T) in exon 5, leading to the substitution of glycine by valine at amino acid position 271 (G271V) of the predicted protein. The same mutation with a comparable localization has been previously described for KCNQ3 in benign familial neonatal convulsions (BFNC). The glycine at this position (G271) is located in pore region of KCNQ2 protein and is evolutionarily highly conserved. The same SSCP variant as that of the proband was shown in the rest of the affected members of this family but not in the unaffected members enrolled in the study of this family and all the 75 unrelated normal individuals. CONCLUSION: Previously reported mutations of KCNQ2 were mainly identified in BFNC family in which at least one individual had an onset of seizures during the first week of life, a hallmark of the BFNC disorder. The results of the present study suggest the possibility that KCNQ2 mutation exist in patients with BFIC diagnosis. G812T of KCNQ2 gene is a novel mutation found in BFIC and functional expression of KCNQ2 G812T is required for understanding the mechanism of BFIC and other idiopathic epilepsy.

[Optimal therapeutic window of hyperbaric oxygenation in neonatal rat with hypoxic-ischemic brain damage].

OBJECTIVE: Hyperbaric oxygenation (HBO) is an attractive procedure that has been used in treatment of hypoxic-ischemic encephalopathy (HIE). However, depending on the HBO protocol, especially the time point of starting treatment of HBO, different and conflicting results were obtained. This study was undertaken to search for the optimal therapeutic window of ABO in neonatal rat with hypoxic-ischemic brain damage (HIBD). METHODS: Eighty-four healthy seven-day-old SD rats were used as research subjects and were randomly divided into seven groups with 12 in each: sham group, HI group, HI (1 h) + HBO group (HBO starting 1 h after HI), HI (3 h) + HBO group (HBO starting 3 h after HI), HI (6 h) + HBO group (HBO starting 6 h after HI), HI (12 h) + HBO group (HBO starting 12 h after HI), HI (24 h) + HBO group (HBO starting 24 h after HI). Single HBO treatment (2.5 atmospheres absolute, ATA for 1.5 h) was used in this study. Two indexes were used to assess the effect of HBO that included short-term (48 h after HI) histology change (the cell density in CA1 of hippocampus and cortex) and long-term (5 w and 6 w after HI) neurobehavioral testing (grip test and treadmill test for evaluating the deficits of sensor motor; step-down avoidance test for assessing the deficits of memory). RESULTS: In HI (1 h) + HBO, HI (3 h) + HBO and HI (6 h) + HBO groups, neuron density of cortex and CA1 of hippocampus were 1981.76 +/- 299.55, 1841.53 +/- 241.21, 1525.78 +/- 189.00 and 4430.56 +/- 1180.31, 4507.54 +/- 1374.32, 3883.48 +/- 821.87, respectively, which were significantly higher than HIBD group (987.86 +/- 285.39 and 1813.59 +/- 295.33, P < 0.05, ANOVA). But in HI (12 h) + HBO and HI (24 h) + HBO, the neuron density of cortex and CA1 of hippocampus compared with those in HIBD group had no statistical significance (P > 0.05, ANOVA). In the sensor motor testing performed at 5 w after HI of rat, the grip time in grip test and the stay time in treadmill test of HI (1 h) + HBO, HI (3 h) + HBO and HI (6 h) + HBO groups were 193.39 +/- 51.19, 168.39 +/- 34.02, 168.95 +/- 34.93 and 130.34 +/- 42.56, 128.20 +/- 27.69, 125.74 +/- 36.99, respectively, which, compared with HIBD group, were significantly prolonged (P < 0.05, ANOVA). But in HI (12 h) + HBO and HI (24 h) + HBO groups, the time was not significantly longer compared with HI (P > 0.05, ANOVA). In the step-down avoidance test which was performed at 6 w after HI, the step-down latencies of HI (1 h) + HBO, HI (3 h) + HBO and HI (6 h) + HBO were 96.91 +/- 29.91, 90.35 +/- 28.44 and 76.46 +/- 38.70, respectively, which were significantly prolonged (P < 0.05, ANOVA), but in HI (12 h) + HBO and HI (24 h) + HBO, the latencies did not significantly increase compared with HIBD, P > 0.05, ANOVA. CONCLUSIONS: The optimal therapeutic window of HBO in neonatal rat with HIBD was within the first 6 hours after HI. In this therapeutic window, HBO was highly effective in reducing the cell loss in CA1 of hippocampus and cortex.