Risk stratification of hemodynamically significant patent ductus arteriosus by clinical and genetic factors

BACKGROUND

Hemodynamically significant patent ductus arteriosus (hsPDA) is associated with increased comorbidities in neonates. Early evaluation of hsPDA risk is critical to implement individualized intervention. The aim of the study was to provide a powerful reference for the early identification of high-risk hsPDA population and early treatment decisions.

METHODS

We enrolled infants who were diagnosed with PDA and performed exome sequencing. The collapsing analyses were used to find the risk gene set (RGS) of hsPDA for model construction. The credibility of RGS was proven by RNA sequencing. Multivariate logistic regression was performed to establish models combining clinical and genetic features. The models were evaluated by area under the receiver operating curve (AUC) and decision curve analysis (DCA).

RESULTS

In this retrospective cohort study of 2199 PDA patients, 549 (25.0%) infants were diagnosed with hsPDA. The model [all clinical characteristics selected by least absolute shrinkage and selection operator regression (all CCs)] based on six clinical variables was acquired within three days of life, including gestational age (GA), respiratory distress syndrome (RDS), the lowest platelet count, invasive mechanical ventilation, and positive inotropic and vasoactive drugs. It has an AUC of 0.790 [95% confidence interval (CI) = 0.749-0.832], while the simplified model (basic clinical characteristic model) including GA and RDS has an AUC of 0.753 (95% CI = 0.706-0.799). There was a certain consistency between RGS and differentially expressed genes of the ductus arteriosus in mice. The AUC of the models was improved by RGS, and the improvement was significant (all CCs vs. all CCs + RGS: 0.790 vs. 0.817, P < 0.001). DCA demonstrated that all models were clinically useful.

CONCLUSIONS

Models based on clinical factors were developed to accurately stratify the risk of hsPDA in the first three days of life. Genetic features might further improve the model performance. Video Abstract (MP4 86834 kb).

[A family with early onset myopathy caused by MEGF10 gene defect and literature review]

Objective: To summarize the genetic and clinical phenotypic characteristics of patients with early-onset myopathy, areflexia, respiratory distress and dysphagia (EMARDD) caused by multiple epidermal growth factor 10 (MEGF10) gene defect. Methods: The clinical data of 3 infants in 1 family with EMARDD caused by MEGF10 gene defect diagnosed in the Department of Neonatology, Xiamen Children's Hospital in April 2022 were analyzed retrospectively. Using "multiple epidermal growth factor 10" "myopathy" or "MEGF10" "myopathy" as the key words, and searching the relevant literature reports of CNKI, Wanfang Database and PubMed Database from the establishment of the database to September 2022. Combined with this family, the main clinical information and genotype characteristics of EMARDD patients caused by MEGF10 gene defect were summarized. Results: The proband, male, first infant of monozygotic twins, was admitted to hospital 7 days after birth "due to intermittent cyanosis with weak sucking". The infant had dysphagia accompanied with cyanosis of lips during feeding and crying after birth. Physical examination on admission revealed reduced muscle tone of the extremities, flexion of the second to fifth fingers of both hands with limited passive extension of proximal interphalangeal joints, and limited abduction of both hips. He was diagnosed as dysphagia of newborn, congenital dactyly. After admission, he was given limb and oral rehabilitation training, breathing gradually became stable and oral feeding fully allowed, and discharged along with improvement. The younger brother of the proband was admitted to the hospital at the same time, and his clinical manifestations, diagnosis and treatment process were the same as those of the proband. The elder brother of the proband died at the age of 8 months due to the delayed growth and development, severe malnutrition, hypotonia, single palmoclal crease and weak crying. A whole exon sequencing of the family was done, and found that the 3 children were all compound heterozygous variations at the same site of MEGF10 gene, with 2 splicing variants (c.218+1G>A, c.2362+1G>A), which came from the father and mother respectively, and the new variation was consistent with the autosomal recessive inheritance model. Three children were finally diagnosed as EMARDD caused by MEGF10 gene defect. There are 0 Chinese literature and 18 English literature that met the search conditions. Totally 17 families including 28 patients were reported. There were 31 EMARDD patients including 3 infants from this family. Among them, there were 13 males and 18 females. The reported age of onset ranged from 0 to 61 years. Except for 5 patients with incomplete clinical data, 26 patients were included in the analysis of phenotypic and genotypic characteristics. The clinical features were mainly dyspnea (25 cases), scoliosis (22 cases), feeding difficulties (21 cases), myasthenia (20 cases), and other features including areflexia (16 cases) and cleft palate or high palatal arch(15 cases). Muscle biopsy showed non-specific changes, with histological characteristics ranging from slight muscle fiber size variation to minicores change which was seen in all 5 patients with at least 1 missense mutation of allele. In addition, the adult onset was found in patients with at least 1 missense variant of MEGF10 gene. Conclusions: MEGF10 gene defect related EMARDD can occur in the neonatal period, and the main clinical features are muscle weakness, breathing and feeding difficulties. Patients with myopathy who have at least 1 missense mutation and muscle biopsy indicating minicores change may be relatively mild.

[Clinical practice of whole-genome sequencing in the rapid diagnosis of critically ill neonates]

OBJECTIVES

To explore the application of whole-genome sequencing (WGS) in the rapid clinical diagnosis of critically ill neonates.

METHODS

The critically ill neonates who admitted to the neonatal intensive care unit of Children's Hospital of Fudan University and underwent WGS from August to September, 2019 were enrolled in this prospective study. The genetic testing results and clinical outcome were analyzed with reference to the sequencing data and clinical features of the neonates.

RESULTS

A total of 15 neonates were tested, among whom there were 9 boys and 6 girls. The main reason for hospitalization included abnormal breathing in 7 neonates, poor response in 2 neonates, feeding difficulty in 2 neonates, fever in 1 neonate, hypothermia in 1 neonate, preterm birth in 1 neonate, and convulsion in 1 neonate. The mean turn-around time was 4.5 days for WGS. Finally a genetic diagnosis was obtained for 3 neonates, with a positive diagnostic rate of 20% (3/15). Among the 3 neonates, 2 neonates were withdrawn from the treatment due to severe conditions and 1 neonate died on the day when the sample was sent for genetic testing, whose etiology could be explained by the results of genetic testing.

CONCLUSIONS

WGS technique can provide a timely and effective diagnosis for critically ill neonates suspected of genetic diseases and provide genetic evidence for clinical treatment of critically ill cases.

Monkeypox and the perinatal period: what does maternal-fetal medicine need to know?

BACKGROUND

After the global elimination of smallpox, monkeypox has become the most threatening orthopoxvirus to human health. Very few studies have been reported on pregnant women and newborns. In the case of monkeypox infection, the virus can cause serious adverse pregnancy events in women, which can lead to fetal or neonatal death.

DATA SOURCES

We made a comprehensive review after an extensive literature search in the PubMed/Medline database and websites concerning smallpox and monkeypox.

RESULTS

Two case reports reported a total of nine pregnant women, six of whom had fetal deaths. In the autopsy of a stillbirth, researchers found that the placenta was infected with monkeypox virus, but the mechanism of infection remains unclear. Smallpox vaccine should be administered to acutely exposed pregnant women and newborns. Several novel recombinant vaccinia immunogloblin (rVIG) and human-specific monoclonal antibodies are being developed for the prevention and treatment of monkeypox virus infection. After the fetus was delivered, the newborn should take a bath as soon as possible to remove the amniotic fluid and dirt from the body. The appropriate isolation protocol for the newborn should be selected according to the infection status of the mother. It is not known whether monkeypox virus is present in breast milk, and pasteurized breast milk can be given to newborns when breastfeeding is considered.

CONCLUSION

This review presents an overview of monkeypox in the perinatal period and guides the future research direction.

[Clinical analysis of 15 patients with epileptic spasms and focal seizures as a single ictal event in neonatal period]

Objective: To investigate the phenomenon of epileptic spasms (ES) and focal seizures (FS) in a single ictal event (FS-ES phenomenon) and to study the etiology, manifestations, and prognosis of this phenomenon. Methods: The data of the 15 neonates who had ES and FS in a single ictal event, according to video-electroencephalography (VEEG) recording in Department of Neonatology of Children's Hospital of Fudan University during the period of January 2018 to December 2019, was analyzed retrospectively. Results: Of the 15 neonates, 7 were male and 8 were female. Gestational age was 39 (32-42) weeks. Birth weight was 3 100 (1 825-3 850) g. The initial onset age of convulsions was 2 (1-10) days. The age of the first discovery of FS-ES phenomenon was 25 (14-32) days. The age of seizure-free was 7(1-27) months. All of the initial seizure types were FS. The FS-ES phenomenon of 15 patients started with FS. The FS-ES phenomenon manifested in 2 forms: FS followed by ES (12 cases), ES appeared during an FS without interrupting FS (2 cases). In 1 neonate the spasm occurred in both forms. The etiology included genetic factors (9 cases), intracranial infection (1 case), abnormal brain tissue structure (2 cases), and etiology was unknown in 3 cases. All the neonates had a poor prognosis except one. Conclusions: The FS-ES phenomenon in the neonatal period starts with FS. There are various etiologies. Etiologies of most patients are genetic factors. Most of the patients have a poor prognosis.

Diversity of the T cell receptor β chain complementarity-determining region 3 in peripheral blood of neonates with sepsis: an analysis based on immune repertoire sequencing

OBJECTIVES

To investigate the diversity of peripheral blood T cell receptor (TCR) β chain complementarity-determining region 3 (CDR3) based on immune repertoire sequencing in neonates with sepsis and the possible pathogenesis of neonatal sepsis.

METHODS

A total of 12 neonates with sepsis were enrolled as the case group, and 9 healthy full-term infants, matched for gestational age, birth weight, and age, were enrolled as the control group. Omega nucleic acid purification kit (SQ blood DNA Kit II) was used to extract DNA from peripheral blood samples, TCR β chain CDR3 was amplified by multiplex PCR, and then high-throughput sequencing was performed for the products to analyze the diversity of TCR β chain CDR3 and the difference in expression.

RESULTS

The length and type of TCR β chain CDR3 were similar between the case and control groups, and Gaussian distribution was observed in both groups. With D50 and Shannon-Wiener index as the evaluation indices for diversity, the case group had a significantly lower diversity of TCR β chain CDR3 than the control group (P<0.05). The frequency of 48 genes in TCR β chain V segment was compared, and the results showed that compared with the control group, the case group had significantly higher frequencies of TRBV10-3, TRBV2, and TRBV20-1 (P<0.05). The frequency of 13 genes in TCR β chain J segment were compared, and the results showed that compared with the control group, the case group had significantly higher frequencies of TRBJ2-3, TRBJ2-5, and TRBJ2-7 (P<0.05).

CONCLUSIONS

There is a significant change in the diversity of TCR β chain CDR3 in the peripheral blood of neonates with sepsis, suggesting that it might be associated with the immune pathogenesis of neonatal sepsis.

Early initial video-electro-encephalography combined with variant location predict prognosis of KCNQ2-related disorder

BACKGROUND

The clinical features of KCNQ2-related disorders range from benign familial neonatal seizures 1 to early infantile epileptic encephalopathy 7. The genotype-phenotypic association is difficult to establish.

OBJECTIVE

To explore potential factors in neonatal period that can predict the prognosis of neonates with KCNQ2-related disorder.

METHODS

Infants with KCNQ2-related disorder were retrospectively enrolled in our study in Children's Hospital of Fudan University in China from Jan 2015 to Mar 2020. All infants were older than age of 12 months at time of follow-up, and assessed by Bayley Scales of Infant and Toddler Development-Third Edition (BSID-III) or Wechsler preschool and primary scale of intelligence-fourth edition (WPPSI-IV), then divided into three groups based on scores of BSID-III or WPPSI-IV: normal group, mild impairment group, encephalopathy group. We collected demographic variables, clinical characteristics, neuroimaging data. Considered variables include gender, gestational age, birth weight, age of the initial seizures, early interictal VEEG, variant location, delivery type. Variables predicting prognosis were identified using multivariate ordinal logistic regression analysis.

RESULTS

A total of 52 infants were selected in this study. Early interictal video-electro-encephalography (VEEG) (β = 2.77, 1.20 to 4.34, P = 0.001), and variant location (β = 2.77, 0.03 to 5.5, P = 0.048) were independent risk factors for prognosis. The worse the early interictal VEEG, the worse the prognosis. Patients with variants located in the pore-lining domain or S4 segment are more likely to have a poor prognosis.

CONCLUSIONS

The integration of early initial VEEG and variant location can predict prognosis. An individual whose KCNQ2 variant located in voltage sensor, the pore domain, with worse early initial VEEG background, often had an adverse outcome.

Non-invasive cardiac output measurement by electrical cardiometry and M-mode echocardiography in the neonate: a prospective observational study of 136 neonatal infants

BACKGROUND

Electrical cardiometry (EC) is a continuous, non-invasive method for measuring cardiac output (CO). This study investigates the correlation and consistency of CO values in newborns obtained by using EC and M-mode echocardiography (Teichholz formula).

METHODS

In this prospective observational study, simultaneous measurement of CO was implemented with EC (COec) and M-mode echocardiography (COm) in neonates. The absolute values of CO measured by the two methods were converted to Z-scores. Following that, Pears's correlation analyses and the Bland-Altman index were employed to analyze the correlation and consistency of COec Z-scores and COm Z-scores.

RESULTS

A total of 136 neonates (93 preterm infants) were enrolled in this study, and EC and M-mode echocardiography comparative studies were conducted 155 times. The mean value of COec and COm demonstrated significant statistical differences (P<0.001). A moderate correlation (r=0.601; P<0.001) was found between the two methods. The Bland-Altman index value was 3.2%, which remained less than 5% in the low birth weight (LBW) (2.1%), non-LBW (3.4%), spontaneous respiration (3.1%), nasal continuous positive airway pressure (nCPAP) (4.0%), mechanical ventilation (2.9%), hemodynamic significance of the patent ductus arteriosus (hsPDA) (4.3%), and non-hsPDA (3.7%) groups, respectively.

CONCLUSIONS

Although the absolute values of CO measured by EC and M-mode echocardiography were not interchangeable, the distribution of CO in EC and M-mode echocardiography was similar.

Genetic etiologies associated with infantile hydrocephalus in a Chinese infantile cohort

BACKGROUND

Infantile hydrocephalus (IHC) is commonly related to other central nervous system diseases, which may have adverse effects on prognosis. The causes of IHC are heterogeneous, and the genetic etiologies are not fully understood. This study aimed to analyze the genetic etiologies of an IHC cohort.

METHODS

The data for 110 IHC patients who had received exome sequencing at the Clinical Genetic Center of the Children's Hospital of Fudan University between 2016 and 2019 were reviewed and analyzed retrospectively. An exome-wide association analysis (EWAS) was performed within this cohort using IHC as the study phenotype.

RESULTS

Of the 110 IHC patients, a pathogenic or likely pathogenic variant was identified in 16 (15%) patients, spanning 13 genes. The genes were mainly associated with metabolic disorders, brain abnormalities, and genetic syndromes. IHC patients who had unclear clinical etiology were more likely to possess a genetic etiology. Based on previous studies and on our EWAS results, ZEB1, SBF2, and GNAI2 were over-represented among IHC patients and might affect the signaling pathways involved in IHC formation.

CONCLUSIONS

Our study showed heterogeneous genetic etiologies in an IHC cohort. It is essential to perform genetic testing on IHC patients who have unclear clinical etiology, and genes associated with metabolic disorders, brain abnormalities, and genetic syndromes should be noted. In addition, when aiming to discover IHC susceptibility genes, genes that might influence the signaling pathways involved in IHC formation should be prioritized.

Effects of SARS-CoV-2 infection on neuroimaging and neurobehavior in neonates

BACKGROUND

We collected neonatal neurological, clinical, and imaging data to study the neurological manifestations and imaging characteristics of neonates with coronavirus disease 2019 (COVID-19).

METHODS

This case-control study included newborns diagnosed with COVID-19 in Wuhan, China from January 2020 to July 2020. All included newborns had complete neurological evaluations and head magnetic resonance imaging. We normalized the extracted T2-weighted imaging data to a standard neonate template space, and segmented them into gray matter, white matter, and cerebrospinal fluid. The comparison of gray matter volume was conducted between the two groups.

RESULTS

A total of five neonates with COVID-19 were included in this study. The median reflex scores were 2 points lower in the infected group than in the control group (P = 0.0094), and the median orientation and behavior scores were 2.5 points lower in the infected group than in the control group (P = 0.0008). There were also significant differences between the two groups in the total scale score (P = 0.0426). The caudate nucleus, parahippocampal gyrus, and thalamus had the strongest correlations with the Hammersmith neonatal neurologic examination (HNNE) score, and the absolute correlation coefficients between the gray matter volumes and each part of the HNNE score were all almost greater than 0.5.

CONCLUSIONS

We first compared the neurological performance of neonates with and without COVID-19 by quantitative neuroimaging and neurological examination methods. Considering the limited numbers of patients, more studies focusing on the structural or functional aspects of the virus in the central nervous system in different age groups will be carried out in the future.

A term neonate with early myoclonic encephalopathy caused by RARS2 gene variants: a case report

The RARS2 gene encodes mitochondrial arginine-tRNA synthetase. Patients with variants of the RARS2 gene have pontocerebellar hypoplasia type 6 (PCH6), which is characterized by early onset seizures, progressive microcephaly, and developmental delay. PCH6 is a rare mitochondrial encephalopathy. To the best of our knowledge, the onset seizure type which the ictal video-electroencephalogram (VEEG) was compatible with early myoclonic encephalopathy (EME) has not been reported. Here we reported a term female neonate with EME caused by heterozygous variants of the RARS2 gene [NM_020320: exon10: c.773G>A (p. R258H) Maternal, NM_020320: exon4: c.282_285delAGAG Paternal]. Groan was the first symptom manifested, followed by metabolic disorders, and early marked cerebral atrophy. Metabolic disorders were corrected after feeding with extensively hydrolyzed protein formula. Seizures started at the 19th day of life. Interictal VEEG showed a suppression-burst (SB) pattern and ictal VEEG revealed myoclonic seizures that were compatible with early myoclonic encephalopathy (EME). She had frequent myoclonic seizures resistant to multi-antiepileptic drugs including phenobarbital, levetiracetam and oxcarbazepine, and soon developed into convulsive status epilepticus. At 7 months of age, she had severe developmental delay, and developed infantile spasms. Our case report expands the phenotypic spectrum of the PCH6, meanwhile, RARS2 should be considered be a causative gene in patients with EME.

[Genetic screening in early diagnosis of neonatal WAS gene-related disorders]

Objective: To explore the clinical value of genetic screening for early identification of WAS gene-related disorders in newborns. Methods: This was a retrospective study. Neonatal Genome Project from Children's Hospital of Fudan University collected 5 800 high-risk newborns in the neonatal intensive care unit to study the patients' genetic causes using high-throughput sequencing from January 2016 to December 2017. Eleven newborns (all were boys) with pathogenic or likely pathogenic variants in WAS gene were enrolled. Data of clinical characteristics,gene variants and genotype-phenotype correlation were collected and summarized. Results: Eleven patients included 5 cases with Wiskott-Aldrich syndrome (WAS) and 6 cases with X-linked thrombocytopenia (XLT).Two patients with WAS developed clinical manifestations in the early neonatal period,and 3 patients in 5-8 weeks after birth. Three neonates with XLT were hospitalized for other diseases in the first place.Their platelet count was found to be reduced after admission to hospital, and diagnosis was made after genetic testing. Eleven pathogenic or likely pathogenic variants in WAS gene were identified. Among them, 7 were first reported in this study, including 2 frame shift variants c.138delG and c.388_390del, 4 splicing variants c.1453+1G>A,c.734+1G>C,c.135G>A and c.1453+3G>C, and 1 missense variant c.1118C>T. The other 4 reported variants were c.777+1G>A,c.107_108delTT, c.436delC and c.1509_*3delAGTG. Conclusions: The clinical features of WAS gene-related disorders in neonatal period lack specificity. Genetic screening in newborns plays an important role in the early diagnosis of diseases and provides providing evidence for the early intervention.

Novel compound heterozygous mutations in the PEX1 gene in two Chinese newborns with Zellweger syndrome based on whole exome sequencing

Peroxisome biogenesis disorders (PBDs) represent a spectrum of human genetic disorders that are characterized by damaged peroxisome assembly. In the newborn period, the characteristics of affected patients include dysmorphic facial features, neonatal hypotonia, seizures, ocular abnormalities, poor feeding, liver cysts with hepatic dysfunction and skeletal defects. These can be caused by a defect in at least 14 different PEX genes. In this study, whole-exome sequencing (WES) was performed on samples from two Chinese newborns with clinical features of Zellweger syndrome. WES identified two novel mutations (c.2416+1G>T and c.2489delT) in patient 1 and another two novel mutations (c.1483+1G>A and c.1727dupG) in patient 2 in the PEX1 gene. All four mutations have a serious influence on the protein function, which also highlights the power of WES, particularly in clinically challenging cases.

Periostin Promotes Neural Stem Cell Proliferation and Differentiation following Hypoxic-Ischemic Injury

Neural stem cell (NSC) proliferation and differentiation are required to replace neurons damaged or lost after hypoxic-ischemic events and recover brain function. Periostin (POSTN), a novel matricellular protein, plays pivotal roles in the survival, migration, and regeneration of various cell types, but its function in NSCs of neonatal rodent brain is still unknown. The purpose of this study was to investigate the role of POSTN in NSCs following hypoxia-ischemia (HI). We found that POSTN mRNA levels significantly increased in differentiating NSCs. The proliferation and differentiation of NSCs in the hippocampus is compromised in POSTN knockout mice. Moreover, NSC proliferation and differentiation into neurons and astrocytes significantly increased in cultured NSCs treated with recombinant POSTN. Consistently, injection of POSTN into neonatal hypoxic-ischemic rat brains stimulated NSC proliferation and differentiation in the subventricular and subgranular zones after 7 and 14 days of brain injury. Lastly, POSTN treatment significantly improved the spatial learning deficits of rats subjected to HI. These results suggest that POSTN significantly enhances NSC proliferation and differentiation after HI, and provides new insights into therapeutic strategies for the treatment of hypoxic-ischemic encephalopathy.

Neuroprotective effects of oligodendrocyte progenitor cell transplantation in premature rat brain following hypoxic-ischemic injury

Periventricular leukomalacia (PVL) is a common ischemic brain injury in premature infants for which there is no effective treatment. The objective of this study was to determine whether transplanted mouse oligodendrocyte progenitor cells (OPCs) have neuroprotective effects in a rat model of PVL. Hypoxia-ischemia (HI) was induced in 3-day-old rat pups by left carotid artery ligation, followed by exposure to 6% oxygen for 2.5 h. Animals were assigned to OPC transplantation or sham control groups and injected with OPCs or PBS, respectively, and sacrificed up to 6 weeks later for immunohistochemical analysis to investigate the survival and differentiation of transplanted OPCs. Apoptosis was evaluated by double immunolabeling of brain sections for caspase-3 and neuronal nuclei (NeuN), while proliferation was assessed using a combination of anti-Nestin and -bromodeoxyuridine antibodies. The expression of brain-derived neurotrophic factor (BDNF) and Bcl-2 was examined 7 days after OPC transplantation. The Morris water maze was used to test spatial learning and memory. The results showed that transplanted OPCs survived and formed a myelin sheath, and stimulated BDNF and Bcl-2 expression and the proliferation of neural stem cells (NSC), while inhibiting HI-induced neuronal apoptosis relative to control animals. Moreover, deficits in spatial learning and memory resulting from HI were improved by OPC transplantation. These results demonstrate an important neuroprotective role for OPCs that can potentially be exploited in cell-based therapeutic approaches to minimize HI-induced brain injury.

[Research progress in mild hypothermia treatment of neonatal hypoxic-ischemic encephalopathy]

Randomized controlled trials have demonstrated the safety and efficacy of mild hypothermia in the treatment of neonatal hypoxic-ischemic encephalopathy (HIE), which can reduce mortality or the incidence of severe neurological sequelae. Mild hypothermia has been used in the neonatal intensive care unit (NICU) as a routine treatment method for neonatal HIE in many developed countries, and it is increasingly applied in some NICUs in China. However, 40%-50% of the neonates treated with mild hypothermia die or develop severe neurological disability. Thus, to achieve the best neuroprotective effect, issues such as selection of patients with indications for mild hypothermia, cooling method, optimal time for mild hypothermia, duration of mild hypothermia, optimal target temperature, and the safety and long-term effects of mild hypothermia combined with other therapies, need to be further discussed. This article reviews the latest progress in clinical research on these issues.

[Changes in MLS-BAEP in newborn piglets with hypoxic-ischemic brain damage during selective moderate head cooling therapy]

OBJECTIVE

To study the effect of selective moderate head cooling therapy on maximum length sequences brainstem auditory evoked potential (MLS-BAEP) in newborn piglets with hypoxic-ischemic brain damage.

METHODS

Sixteen newborn piglets aged 5-7 day old were randomly divided into three groups: normothermic control (n=4), HI (n=6) and mild hypothermia-treated (n=6). HI was induced through temporary occlusion of both carotid arteries, followed by mechanical ventilation with low concentration of oxygen (FiO2=0.06) for 30 minutes. Mild hypothermia was induced by equipment via circulating water. MLS-BAER was recorded before HI and at 12 hours, 24 hours, 36 hours, 48 hours, 60 hours, 72 hours, 4 days, 7 days, 10 days, 13 days and 15 days after HI.

RESULTS

Compared with the normothermic control group, all latencies and intervals tended to increase significantly at 72 hours in the HI group and reached peak values on day 7. From day 10, all latencies and intervals tended to decrease, but apart from wave I latency, still differed significantly from those of the normothermic control group. MLS-BAER variables did not reach normal values until day 15. Ⅲ latency, Ⅰ-Ⅲ interval and Ⅰ-Ⅴ interval were significantly reduced in the hypothermia-treated group between 60 and 7 days after HI compared with the HI group (P<0.05). V latency and Ⅲ-Ⅴ interval in the hypothermia-treated group were also reduced compared with the HI group between 72 hours and 7 days after HI (P<0.05).

CONCLUSIONS

Both peripheral and central auditory systems are disturbed by HI, which shows as a significant increase in MLS-BAER variables (all latencies and intervals) in newborn piglets. Involvement in central brainstem auditory system reaches a peak on day 7 after injury. MLS-BAER variables still cannot reach to normal values until day 15. Selective moderate head cooling therapy can significantly reduce brainstem damage induced by HI.

Apoptosis mechanisms of human gastric cancer cell line MKN-45 infected with human mutant p27

AIM

To explore the inducing effect of human mutant p27 gene on the apoptosis of the human gastric cancer cell line MKN-45 and its associated mechanisms.

METHODS

The recombinant adenovirus Ad-p27mt was constructed to infect the human gastric cancer cell line MKN-45. Using flow cytometry, TUNEL assay and DNA fragment analysis, we measured the apoptotic effect of Ad-p27mt on the human gastric cancer cells.

RESULTS

Ad-p27mt was successfully constructed and the infection efficiency reached 100%. After 18 h of infection, we observed an apoptotic hypodiploid peak on the flow cytometer before G1-S and apoptotic characteristic bands in the DNA electrophoresis. The apoptotic rate detected by TUNEL method was significantly higher in the Ad-p27mt group (89.4+/-3.12%) compared to the control group (3.12+/-0.13%, P < 0.01).

CONCLUSION

Human mutant p27 can induce apoptosis of the human gastric cancer cells in vitro.

[Longitudinal observation on the control of intestinal helminthiasis]

OBJECTIVE

To search suitable measure for rapid control intestinal helminthiasis and long-term strengthen efficacy.

METHODS

The treatment was taken in egg-positive population of intestinal helminthiasis in 1986-1988. The treatment was carried out only in the selected population in 1989-1992. No measure was taken in 1993-2000.

RESULTS

(1) The prevalence rate of hookworm, Ascaris and Trichuris decreased to 3.2%, 37.3% and 3.5% respectively after administration of albendazole twice a year for 3 years. (2) The prevalence rate of hookworm continued to decrease to 0.5% after treatment on selected population. (3) The prevalence rate and the intensity of hookworm has been less than 1% and 10/LPG for 8 years. No hookworm larvae had been isolated from the soil.

CONCLUSION

The hookworm transmission was effectively controlled in the study site.

In vivo boron-11 MRI and MRS using (B24H22S2)4- in the rat

In vivo boron-11 magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS) were performed on a rat that had been infused with a potential boron neutron capture therapy agent, Na4B24H22S2, using methods for detecting nuclei with a short T2 relaxation time. MRI and MRS were also performed on a euthanized rat that had been similarly infused in vivo. Boron-11 spectral intensities decreased in the living rat over a 25-h period. The results demonstrate the capability of MRI and MRS to noninvasively monitor the distribution and excretion of boron agents in vivo.