Plasma midkine concentrations in healthy children, children with increased and decreased adiposity, and children with short stature.

BACKGROUND: Midkine (MDK), one of the heparin-binding growth factors, is highly expressed in multiple organs during embryogenesis. Plasma concentrations have been reported to be elevated in patients with a variety of malignancies, in adults with obesity, and in children with short stature, diabetes, and obesity. However, the concentrations in healthy children and their relationships to age, nutrition, and linear growth have not been well studied. SUBJECTS AND METHODS: Plasma MDK was measured by immunoassay in 222 healthy, normal-weight children (age 0-18 yrs, 101 boys), 206 healthy adults (age 18-91 yrs, 60 males), 61 children with BMI ≥ 95th percentile (age 4-18 yrs, 20 boys), 20 girls and young women with anorexia nervosa (age 14-23 yrs), and 75 children with idiopathic short stature (age 3-18 yrs, 42 boys). Body fat was evaluated by dual-energy X-ray absorptiometry (DXA) in a subset of subjects. The associations of MDK with age, sex, adiposity, race/ethnicity and stature were evaluated. RESULTS: In healthy children, plasma MDK concentrations declined with age (r = -0.54, P < 0.001) with values highest in infants. The decline occurred primarily during the first year of life. Plasma MDK did not significantly differ between males and females or between race/ethnic groups. MDK concentrations were not correlated with BMI SDS, fat mass (kg) or percent total body fat, and no difference in MDK was found between children with anorexia nervosa, healthy weight and obesity. For children with idiopathic short stature, MDK concentrations did not differ significantly from normal height subjects, or according to height SDS or IGF-1 SDS. CONCLUSIONS: In healthy children, plasma MDK concentrations declined with age and were not significantly associated with sex, adiposity, or stature-for-age. These findings provide useful reference data for studies of plasma MDK in children with malignancies and other pathological conditions.

[Disturbed maturation of oligodendrocyte progenitors in lipopolysaccharide-induced hypomyelination in cultured forebrain slices of neonatal rats].

INTRODUCTION: This study was performed to determine whether the disturbed maturation of oligodendrocyte (OL) progenitors might be related to lipopolysaccharide (LPS)-induced hypomyelination. MATERIAL AND METHODS: We created organotypic cultures of forebrain slices from neonatal rats and explored the morphological changes of glial cells expressing tumour necrosis factor  (TNF-) following LPS exposure. RESULTS: We observed marked activation of glial fibrillary acidic protein-positive astrocytes and OX42-positive microglia co-labelled with TNF- four days following LPS exposure. Our results further demonstrated a reduced expression of O4-positive and O1-positive OL progenitors; moreover, we found that their morphologies were suggestive of degeneration (e.g., scanty, rounded bodies with short, fragmented processes and/or cytoplasmic condensation). At seven days following LPS exposure, astrocytes and microglia were still co-labelled for TNF-; however, the expression of O4-positive and O1-positive cells somewhat increased compared to the number observed at 4 days; despite remaining undifferentiated and exhibiting immature morphologies, the cells were likely indicative of regeneration. In contrast, O4-positive and O1-positive cells in controls were well-differentiated, displaying round, thick cell bodies and long, branching processes. CONCLUSIONS: In conclusion, maturation arrest and/or under-differentiation of OL progenitors commonly occur during regeneration: they may underlie the degeneration and consequent hypomyelination occurring late after injury, or apoptosis during the acute stage post-injury. Microglia and astrocytes expressing TNF- may also contribute to later myelination failure.

Transient intubation for surfactant administration in the treatment of respiratory distress syndrome in extremely premature infants.

PURPOSE: To investigate the effectiveness of transient intubation for surfactant administration and extubated to nasal continuous positive pressure (INSURE) for treatment of respiratory distress syndrome (RDS) and to identify the factors associated with INSURE failure in extremely premature infants. METHODS: Eighty-four infants with gestational age less than 28 weeks treated with surfactant administration for RDS for 8 years were included. Perinatal and neonatal characteristics were retrospectively reviewed, and major pulmonary outcomes such as duration of mechanical ventilation (MV) and bronchopulmonary dysplasia (BPD) plus death at 36-week postmenstrual age (PMA) were compared between INSURE (n=48) and prolonged MV groups (n=36). The factors associated with INSURE failure were determined. RESULTS: Duration of MV and the occurrence of BPD at 36-week PMA were significantly lower in INSURE group than in prolonged MV group (P<0.05), but BPD plus death at 36-week PMA was not significantly different between the 2 groups. In a multivariate analysis, a reduced duration of MV was only significantly associated with INSURE (P=0.001). During the study period, duration of MV significantly decreased over time with an increasing rate of INSURE application (P<0.05), and BPD plus death at 36-week PMA also tended to decrease over time. A low arterial-alveolar oxygen tension ratio (a/APO2 ratio) was a significant predictor for INSURE failure (P=0.001). CONCLUSION: INSURE was the noninvasive ventilation strategy in the treatment of RDS to reduce MV duration in extremely premature infants with gestational age less than 28 weeks.

A case of hypersensitivity to mosquito bite associated with Epstein-barr viral infection and natural killer cell lymphocytosis.

Hypersensitivity to mosquito bites (HMB) is a disorder characterized by a necrotic skin reaction and generalized symptoms subsequent to mosquito bites. It has been suggested that HMB is associated with chronic Epstein-Barr virus (EBV) infection and natural killer cell leukemia/lymphoma. We describe here a Korean child who had HMB associated with chronic EBV infection and natural killer cell lymphocytosis. A 5-yr-old boy was suffered from necrotic skin lesions on the right ear lobe. Type A EB virus was detected from hlood cells and bone marrow biospy recognized hemophagocyrosis.

Multidetector computed tomography of the ring-sling complex in an infant.

The ring-sling complex is a rare congenital vascular and tracheobronchial anomaly. This report describes a 42-day-old infant who presented with congestive heart failure due to patent ductus arteriosus. The ring-sling complex was confirmed by multidetector computed tomography and surgery.

Expression of CD95 and CD95L on astrocytes in the CA1 area of the immature rat hippocampus after hypoxia-ischemia injury.

The immature brain is affected profoundly by hypoxia-ischemia (HI) injury, which can lead to permanent neurologic sequelae in survivors. Neuronal degeneration after HI injury usually is achieved through apoptosis. Both CD95 and its natural ligand, CD95L, which are key molecules in the regulation of apoptosis, are constitutively expressed by neurons and astrocytes during embryonic and early postnatal stages. Further, CD95 or CD95L may have a functional relationship in glial cells and lead to apoptosis of these cells. The hippocampus, especially the CA1 area, is particularly susceptible to HI injury. We therefore investigated the temporal and spatial alterations in CD95 and CD95L expression in the CA1 area of 7-d-old rats after unilateral ligation of the carotid artery. Using immunohistochemistry and Western blotting, we showed that expression of CD95 and CD95L in the hippocampus peaked at 12 h and then decreased. In addition, we used terminal deoxynucleotidyl transferase-mediated digoxigenin-dUTP nick end-labeling to demonstrate apoptosis among CD95- and CD95L-reactive cells. Our findings show that increases in the expression of CD95 and CD95L after HI injury may involve astrocytic apoptosis in the 7-d-old rat hippocampus, and these molecules may act as targets or inducers of cell death.

Endoscopic investigation of the internal organs of a 15th-century child mummy from Yangju, Korea.

Our previous reports on medieval mummies in Korea have provided information on their preservation status. Because invasive techniques cannot easily be applied when investigating such mummies, the need for non-invasive techniques incurring minimal damage has increased among researchers. Therefore, we wished to confirm whether endoscopy, which has been used in non-invasive and minimally invasive studies of mummies around the world, is an effective tool for study of Korean mummies as well. In conducting an endoscopic investigation on a 15th-century child mummy, we found that well-preserved internal organs remained within the thoracic, abdominal and cranial cavities. The internal organs - including the brain, spinal cord, lung, muscles, liver, heart, intestine, diaphragm and mesentery - were easily investigated by endoscopy. Even the stool of the mummy, which accidentally leaked into the abdominal cavity during an endoscopic biopsy, was clearly observed. In addition, unusual nodules were found on the surface of the intestines and liver. Our current study therefore showed that endoscopic observation could provide an invaluable tool for the palaeo-pathological study of Korean mummies. This technique will continue to be used in the study of medieval mummy cases in the future.

Protective effect of growth hormone on neuronal apoptosis after hypoxia-ischemia in the neonatal rat brain.

Recent studies have shown that growth hormone (GH) can reduce neuronal loss after hypoxic-ischemic injury (HI) in neonatal and juvenile rat brains. Here, we investigated whether GH exerts its neuroprotective role through an anti-apoptotic effect in neonatal rat brains damaged by severe HI. Gross and histological observations showed that the extent of brain damage was found to be reduced in GH-treated brain at E7 after injury. In a terminal transferase-mediated dUTP nick-end-labeling (TUNEL) study, TUNEL-positive apoptotic cells were localized only at the damaged region in animals treated with saline, which was confirmed by an electron microscopy. In an immunohistochemical study with anti-bcl-2, -bax, -bad, -neuronal nitric oxide synthase (nNOS), -inducible NOS (iNOS) and -endothelial NOS (eNOS) antibodies, we observed that bax, bad, iNOS and eNOS were elevated in the saline-treated group. This study thus suggests that the protective role of GH against HI injury is mediated thorough an anti-apoptotic effect, which offers the possibility of a GH application for the treatment of neonatal HI encephalopathy.

Growth-associated protein-43 is elevated in the injured rat sciatic nerve after low power laser irradiation.

Low power laser irradiation (LPLI) has been used in the treatment of peripheral nerve injury. In this study, we verified its therapeutic effect on neuronal regeneration by finding elevated immunoreactivities (IRs) of growth-associated protein-43 (GAP-43), which is up-regulated during neuronal regeneration. Twenty Sprague-Dawley rats received a standardized crush injury of the sciatic nerve, mimicking the clinical situations accompanying partial axonotmesis. The injured nerve received calculated LPLI therapy immediately after injury and for 4 consecutive days thereafter. The walking movements of the animals were scored using the sciatic functional index (SFI). In the laser treated rats, the SFI level was higher in the laser treated animals at 3-4 weeks while the SFIs of the laser treated and untreated rats reached normal levels at 5 weeks after surgery. In immunocytochemical study, although GAP-43 IRs increased both in the untreated control and the LPLI treated groups after injury, the number of GAP-43 IR nerve fibers was much more increased in the LPLI group than those in the control group. The elevated numbers of GAP-43 IR nerve fibers reached a peak 3 weeks after injury, and then declined in both the untreated control and the LPLI groups at 5 weeks, with no differences in the numbers of GAP-43 IR nerve fibers of the two groups at this stage. This immunocytochemical study using GAP-43 antibody study shows for the first time that LPLI has an effect on the early stages of the nerve recovery process following sciatic nerve injury.