Dysregulation of miR-431 and target gene FOXA1 in intestinal tissues of infants with necrotizing enterocolitis.

The level of microRNA (miR)-431 was found to be markedly up-regulated in intestinal tissue of necrotizing enterocolitis (NEC). The objective of this study was to identify the target gene of miR-431 and to investigate the role of the miR-431-FOXA1 axis in the pathophysiology of NEC. The target gene of miR-431 was identified by in silico target prediction bioinformatics, luciferase assay, and Western blotting. Effects of miR-431 on downstream expression signals, cell proliferation, and apoptosis were investigated by overexpression in Caco-2 cells upon stimulation by LPS or lipoteichoic acid (LTA). FOXA1 was identified as the target gene of miR-431. Overexpression of miR-431 in Caco-2 cells significantly inhibited FOXA1, ESRRG, and HNF4A and activated IL-6, LGR5, NFKB2, PLA2G2A, PRKCZ, and TNF. IL-8 and - 10 were enhanced when costimulated with LPS or LTA. These potential downstream genes were also significantly dysregulated in primary NEC tissues compared with surgical-control tissues. Overexpression of miR-431 significantly decreased proliferation and increased apoptosis of Caco-2 cells. A proposed network of miR-431-FOXA1 interaction with LPS and LTA receptors demonstrates dysregulation of transcription factors, inflammatory mediators, epithelium tight junction regulators, and cell proliferation and apoptosis signals. The miR-431-FOXA1 axis could in part be responsible for the intensification of the inflammatory response in NEC tissues and contribute to the proinflammatory pathophysiology.-Wu, Y. Z., Chan, K. Y. Y., Leung, K. T., Lam, H. S., Tam, Y. H., Lee, K. H., Li, K., Ng, P. C. Dysregulation of miR-431 and target gene FOXA1 in intestinal tissues of infants with necrotizing enterocolitis.

MDSCs drive the process of endometriosis by enhancing angiogenesis and are a new potential therapeutic target.

Endometriosis affects women of reproductive age via unclear immunological mechanism(s). Myeloid-derived suppressor cells (MDSCs) are a heterogeneous group of myeloid cells with potent immunosuppressive and angiogenic properties. Here, we found MDSCs significantly increased in the peripheral blood of patients with endometriosis and in the peritoneal cavity of a mouse model of surgically induced endometriosis. Majority of MDSCs were granulocytic, produced ROS, and arginase, and suppressed T-cell proliferation. Depletion of MDSCs by antiGr-1 antibody dramatically suppressed development of endometrial lesions in mice. The chemokines CXCL1, 2, and 5 were expressed at sites of lesion while MDSCs expressed CXCR-2. These CXC-chemokines promoted MDSC migration toward endometriotic implants both in vitro and in vivo. Also, CXCR2-deficient mice show significantly decreased MDSC induction, endometrial lesions, and angiogenesis. Importantly, adoptive transfer of MDSCs into CXCR2-KO mice restored endometriotic growth and angiogenesis. Together, this study demonstrates that MDSCs play a role in the pathogenesis of endometriosis and identifies a novel CXC-chemokine and receptor for the recruitment of MDSCs, thereby providing a potential target for endometriosis treatment.

Plasma miR-1290 Is a Novel and Specific Biomarker for Early Diagnosis of Necrotizing Enterocolitis-Biomarker Discovery with Prospective Cohort Evaluation.

OBJECTIVE: To discover specific circulating microRNA (miRNA) biomarkers for the early differentiation of necrotizing enterocolitis (NEC) from neonatal sepsis and inflammatory conditions. STUDY DESIGN: The study comprised 3 distinct phases: differential microarray analysis to compare plasma miRNA expression profiles of NEC vs sepsis and non-NEC/nonsepsis cases, a case-control study to quantify dysregulated miRNAs as potential specific biomarkers of NEC, and a prospective cohort study to assess the diagnostic usefulness of the best miRNA biomarker(s). RESULTS: A distinct miRNA expression profile was observed in the NEC compared with the sepsis and non-NEC/nonsepsis groups. miR-1290, miR-1246, and miR-375 were discovered to be specific biomarkers of NEC in the case-control study. In the cohort study (n = 301), plasma miR-1290 (day 0; >220 copies/µL) provided the greatest diagnostic usefulness for identifying both mild medical and severe surgical NEC cases. Of 20 infants with miR-1290 >650 copies/µL, 15 were diagnosed with NEC. Incorporating C-reactive protein (day 1; >15.8 mg/L) for cases with intermediate levels (220-650 copies/µL) in a 2-stage algorithm further optimized the diagnostic profile with a sensitivity of 0.83, a specificity of 0.96, a positive predictive value of 0.75, and a negative predictive value of 0.98. Importantly, 7 of 36 infants with NEC (19.4%) could be diagnosed 7.8-32.2 hours earlier (median, 13.3 hours) using miR-1290. CONCLUSIONS: Plasma miR-1290 is a novel and specific biomarker that can effectively differentiate NEC cases from neonatal sepsis. miR-1290 facilitates neonatologists to confidently and timely reach a decision for early transfer of sick infants with NEC from community-based hospitals to tertiary surgical centers.

Attitudes of Parents and Health Care Workers to Major Surgery for High-Risk Preterm Infants.

OBJECTIVES: To assess preferences of health care workers (HCWs) and parents of term and preterm infants to adverse health outcomes, and how perceived surgical mortality influences decision-making. STUDY DESIGN: A total of 536 participants (157 HCWs, 201 parents of term infants, and 178 parents of preterm infants) were recruited to take part in a structured interview. Preferences related to treatment of a critically ill preterm infant with necrotizing enterocolitis were measured by health state rank permutation analysis and pivotal risk analysis. Between-group and subgroup comparisons were performed. RESULTS: HCWs rank adverse health states less favorably than parents of preterm infants, consistently ranking 2 of the most adverse health states worse than death. Pivotal risk values of HCWs for all health states were consistently the lowest of the 3 groups. High operative mortality was associated uniformly with reduction in pivotal risks for all groups both in favorable and adverse health states. Subgroup analyses revealed significant discrepancies in preferences between fathers and mothers as well as doctors and nurses. Regular religious practice was significantly associated with increased pivotal risks in parental subgroups. CONCLUSIONS: As discrepancies in health state preferences existed between subgroups (ie, doctors vs nurses, mothers vs fathers) and perceived operative mortality consistently biased parental and HCW health state preferences, we recommend that HCWs should first identify differences regarding patient management before interviewing the parents together. HCWs should be aware of inadvertently biasing parents when discussing the risks and outcomes of surgery in conjunction with the overall long-term prognosis of the underlying condition.

Genome-wide expression profiles of necrotizing enterocolitis versus spontaneous intestinal perforation in human intestinal tissues: dysregulation of functional pathways.

OBJECTIVE: To provide a comprehensive database of gene regulation and compare differentially regulated molecular networks in human tissues of necrotizing enterocolitis (NEC) and spontaneous intestinal perforation (SIP). BACKGROUND: Both NEC and SIP are devastating surgical emergencies associated with high morbidity and mortality in preterm infants. Their pathophysiology and molecular mechanisms remain unclear. METHODS: Differential whole genome microarray analysis was performed on intestinal tissues collected from NEC (n = 15) and SIP (n = 12) infants and compared with tissues collected from surgical-control patients with noninflammatory intestinal conditions (n = 14). Validation of 52 target gene expressions was performed by quantitative polymerase chain reaction. Regulatory networks of significantly affected genes were constructed according to functional pathways. RESULTS: Extensive and significant changes of gene expression were observed in NEC tissues, which comprised multiple pathways of angiogenesis, arginine metabolism, cell adhesion and chemotaxis, extracellular matrix remodeling, hypoxia and oxidative stress, inflammation, and muscle contraction. These dysregulated genes could be networked downstream of key receptors, TLR2, TLR4, and TREM1, and mediated via NF-κB, AP-1, and HIF1A transcription factor pathways, indicating predominant microbial and inflammatory involvement. In contrast, SIP tissues exhibited much milder and less diversified expressional changes, with target genes significantly associated with G-protein-mediated muscle contraction and extracellular matrix remodeling. CONCLUSIONS: The molecular evidence suggests that NEC and SIP are likely 2 different diseases caused by distinct etiology and pathophysiology. This first comprehensive database on differential gene expression profiles of human NEC and SIP tissues could lead to development of disease-specific diagnostic and prognostic biomarkers and new therapeutic strategies for improving outcomes.

Neutrophil CD64 for daily surveillance of systemic infection and necrotizing enterocolitis in preterm infants.

BACKGROUND: Early detection and treatment of infected preterm infants could decrease morbidity and mortality. Neutrophil CD64 has been shown to be an excellent early diagnostic biomarker of late-onset sepsis (LOS) and necrotizing enterocolitis (NEC). We aimed to study whether using CD64 as a daily surveillance biomarker could predict LOS/NEC before clinical manifestation. METHODS: We collected 0.1 mL whole blood from very low birth weight (VLBW) infants from day 7 postnatal age until routine daily blood tests were no longer required. Four categories of responses were defined: proven sepsis, clinical sepsis, nonsepsis/non-NEC, and asymptomatic CD64 activation. RESULTS: A total of 146 infants were consecutively recruited and 155 episodes of sepsis evaluation were performed. The biomarker screening utility, sensitivity, specificity, positive predictive value, and negative predictive value for surveillance of LOS/NEC using a cutoff of 5655 antibody-PE (phycoerythrin) molecules bound/cell were 89%, 98%, 41%, and 99.8%, respectively. LOS/NEC was detected a mean of 1.5 days before clinical presentation. However, 63 episodes of CD64 activation occurred in asymptomatic infants who would not otherwise have required sepsis evaluations. CONCLUSIONS: As a surveillance biomarker, neutrophil CD64 detected LOS/NEC 1.5 days before clinical presentation, but at the expense of performing 41% additional sepsis evaluations. This was mainly attributed to an unexpected group of asymptomatic infants with CD64 activation, who recovered spontaneously and did not require antimicrobial treatment. The latter group has not been previously recognized in VLBW infants and could represent subclinical infection secondary to transient bacterial translocation or mild viral infection.

The tetraspanin CD9 regulates migration, adhesion, and homing of human cord blood CD34+ hematopoietic stem and progenitor cells.

The stromal cell-derived factor-1 (SDF-1)/chemokine C-X-C receptor 4 (CXCR4) axis plays a critical role in homing and engraftment of hematopoietic stem/progenitor cells (HSCs) during bone marrow transplantation. To investigate the transcriptional regulation provided by this axis, we performed the first differential transcriptome profiling of human cord blood CD34(+) cells in response to short-term exposure to SDF-1 and identified a panel of genes with putative homing functions. We demonstrated that CD9, a member of the tetraspanin family of proteins, was expressed in CD34(+)CD38(-/lo) and CD34(+)CD38(+) cells. CD9 levels were enhanced by SDF-1, which simultaneously down-regulated CXCR4 membrane expression. Using specific inhibitors and activators, we demonstrated that CD9 expression was modulated via CXCR4, G-protein, protein kinase C, phospholipase C, extracellular signal-regulated kinase, and Janus kinase 2 signals. Pretreatment of CD34(+) cells with the anti-CD9 monoclonal antibody ALB6 significantly inhibited SDF-1-mediated transendothelial migration and calcium mobilization, whereas adhesion to fibronectin and endothelial cells was enhanced. Pretreatment of CD34(+) cells with ALB6 significantly impaired their homing to bone marrow and spleen of sublethally irradiated NOD/SCID (nonobese diabetic/severe combined immune-deficient) mice. Sorted CD34(+)CD9(-) cells displayed lower bone marrow homing capacity compared with that of total CD34(+) cells. CD9 expression on homed CD34(+) cells was significantly up-regulated in vivo. Our results indicate that CD9 might possess specific functions in HSC homing.

IL-15 and macrophage secretory factors facilitate immune activation of neonatal natural killer cells by lipoteichoic acid.

Neonates possess a relatively "naive", yet inducible immune system. Our hypothesis is that upon strategic antigen exposure, cytokine priming and sensitization by accessory cells, natural killer (NK) cells could be activated to become a functional phenotype. We investigated the in vitro stimulation of cord blood (CB) and adult NK cells upon challenge with lipoteichoic acid (LTA), interleukin (IL)-15 and LTA-primed autologous macrophage-conditioned medium, using CD107a and CD69 phenotypes as indicators of activation. We also examined response of CB macrophages to LTA, in terms of P44/42 extracellular signal-regulated kinases (ERK1/2) activation and cytokine secretion. LTA significantly induced secretion of inflammatory cytokines tumor necrotic factor (TNF)-α, IL-6, IL-12 and activated the upstream signal of ERK1/2 phosphorylation in neonatal macrophages. The magnitude of responses to stimulation differed between neonatal and adult NK cells. Co-stimulation with IL-15 was critical for expansion of the CD69 and CD107a NK subpopulations in both neonatal and adult cells, upon a LTA challenge. NK cell activation could be enhanced by LTA-primed autologous macrophages through secretory factors. Our results indicated that neonatal macrophages and NK cells can evoke immunologic responses to a Gram-positive bacterial antigen. The combinatory priming strategy is relevant for development of novel protocols, such as IL-15 treatment, to compensate for the immaturity of the innate immune system in newborns against bacterial infections.

Development of a novel mouse model of severe glucose-6-phosphate dehydrogenase (G6PD)-deficiency for in vitro and in vivo assessment of hemolytic toxicity to red blood cells.

Studies of hemolytic agents on G6PD-deficient subjects have been extensively performed on red blood cells obtained from donors, only using in vitro methods. However, there has been no adequate G6PD-deficient animal model for in vivo assessment of potentially hemolytic agents. The objective of this study is to establish a novel mouse model of severe G6PD-deficiency, with high susceptibility to hemolytic damage upon oxidative agents. To create this model, G6PD mutant Gpdx allele was introduced into the C57L/J mouse strain background by breeding program. The hemolytic toxicity of naphthalene and its metabolite α-naphthol on G6PD-deficient red blood cells was evaluated. Our data showed that the F2 homozygous Gpdx mutant with C57L/J background exhibiting the G6PD activity was 0.9±0.1 U/g Hb, level similar to those of G6PD deficiency in human. A significantly negative correlation was demonstrated between GSH percentage reduction and G6PD activity (r=-0.51, p<0.001) upon challenge of the red blood cells with alpha-naphthol in vitro. Similar correlation was also found between GSSG elevation and G6PD activity. Our in vivo studies showed that the administration of naphthalene at 250 mg/kg inflicted significant oxidative damage to the G6PD-deficient mice, as illustrated by the decrease of the GSH-to-GSSG ratio (by 34.2%, p=0.005) and the increase of the methemoglobin level (by 1.9 fold, p<0.001). Hemolytic anemia was also found in G6PD-deficient mice at this dosage of naphthalene. In summary, this novel mouse model could be utilized as a screening platform to more accurately determine the hemolytic toxicity of pharmacological agents on G6PD-deficient subjects.

Effect of stress on the hypothalamic-pituitary-adrenal axis in the fetus and newborn.

The hypothalamic-pituitary-adrenal (HPA) axis is essential for maintaining homeostasis in the fetus and newborn. A proportion of extremely preterm infants suffer from transient adrenocortical insufficiency of prematurity. Although these infants have suboptimal adrenocortical response to stress in the first week of life, the HPA axis adapts rapidly, and most exhibit an adequate response by day 14. An attenuated cortisol response in preterm infants might be protective against intracranial bleeding. Severe hypoxic-ischemic encephalopathy is a potent stimulus to the HPA axis. Chronic intrauterine hypoxemia can up-regulate the setpoint of the HPA axis and augments adrenal steroidogenic production, resulting in sustained elevation of circulating cortisol levels.

Exploring CCL18, eczema severity and atopy.

BACKGROUND: Childhood atopic dermatitis (AD) is a distressing disease associated with pruritus, sleep disturbance, and impaired quality of life. The pathophysiology of AD is complex, and the chemokine CCL18/pulmonary and activation-regulated chemokine (PARC) may be involved. OBJECTIVE: To evaluate whether CCL18 was associated with disease severity, quality of life, nocturnal scratching, serum eosinophil, and IgE levels. PATIENTS AND METHODS: Patients with AD aged 20 yr or younger were recruited. Disease severity was assessed with the SCORing Atopic Dermatitis (SCORAD) index, quality of life with the Children's Dermatology Life Quality Index (CDLQI), and nocturnal scratching with a wrist motion monitor. Concentrations of plasma CCL18/PARC, serum total IgE, and eosinophil counts were measured in these patients. RESULTS: One hundred and eight patients with AD (mean [s.d.] age of 10.5 [4.4] yr) were recruited. The mean (s.d.) plasma concentration of CCL18/PARC was 162.2 (129.0) pg/ml, respectively. CCL18/PARC was significantly correlated with objective SCORAD (r = 0.44, p < 0.001), extent (r = 0.45, p < 0.001), intensity (r = 0.43, p < 0.001), the symptoms of pruritus (r = 0.20, p = 0.04), and sleep loss (r = 0.19, p = 0.049) but not with CDLQI or nocturnal scratching activities. CCL18/PARC levels were also correlated with eosinophil counts (r = 0.37, p < 0.001) and IgE(log) (r = 0.27, p = 0.005). Positive correlation with SCORAD was present even in patients without bronchial hyper-reactivity. CONCLUSIONS: Serum levels of CCL18 correlate with the clinical severity score, serum eosinophil, and IgE levels. CCL18 is associated with AD and atopy.

Specific IgE of common foods in Chinese children with eczema.

Food atopy is important but inadequately studied among children with atopic dermatitis (AD). We evaluated whether any association existed between AD severity, quality of life, total IgE, eosinophil counts, and the number of food items sensitized. Specific IgE of ten common food items was measured for a group of consecutive AD patients (n=85) enrolled during a randomized trial and correlated the findings with eczema severity. Twenty-four patients (28%) were negative for any of the ten common food items. The most commonly sensitized foods were shrimp (54%), egg white (43%), wheat (42%), and peanut (41%). Atopy to beef as a protein and orange as a fruit were least common among the food items studied, even among patients positive for 8-9 IgE items. Patients with severe AD (objective SCORAD>40) were more likely to be positive for at least one of the food items (Yates corrected p=0.024 for ≥1 food-specific IgE in severe vs. moderate AD, OR 3.42 and 95% CI 1.15-10.32); and for at least seven of the food items (p=0.001 for ≥7 food-specific IgE vs. nil with OR 11.67 and 95% CI 2.29-67.77), respectively. The Spearman coefficients between the number of positive food-specific IgE and total SCORAD, objective SCORAD, area of AD involvement, Children's Dermatology Life Quality Index (CDLQI), total IgE levels, and eosinophil counts were 0.42 (p<0.001), 0.45 (p<0.001), 0.50 (p<0.001), 0.17 (p=0.116), 0.80 (p<0.001), and 0.22 (p=0.043), respectively. Specific IgE levels for beef correlated with all the other food-specific IgE levels, including cow's milk (ρ=0.061, p<0.001) and soy (ρ=0.70, p<0.001). The number of common food items sensitized correlated with disease severity, extent, and total IgE levels. IgE sensitization to beef protein is unlikely in the majority of children with AD, but its serum IgE level is associated with disease severity and risk of sensitization to other foods.

The miR-223/nuclear factor I-A axis regulates inflammation and cellular functions in intestinal tissues with necrotizing enterocolitis.

We previously demonstrated that microRNA(miR)-223 is overexpressed in intestinal tissue of infants with necrotizing enterocolitis (NEC). The objective of the current study was to identify the target gene of miR-223 and to investigate the role of the miR-223/nuclear factor I-A (NFIA) axis in cellular functions that underpin the pathophysiology of NEC. The target gene of miR-223 was identified by in silico target prediction bioinformatics, luciferase assay, and western blotting. We investigated downstream signals of miR-223 and cellular functions by overexpressing the miRNA in Caco-2 and FHs74 cells stimulated with lipopolysaccharide or lipoteichoic acid (LTA). NFIA was identified as a target gene of miR-223. Overexpression of miR-223 significantly induced MYOM1 and inhibited NFIA and RGN in Caco-2 cells, while costimulation with LTA decreased expression of GNA11, MYLK, and PRKCZ. Expression levels of GNA11, MYLK, IL-6, and IL-8 were increased, and levels of NFIA and RGN were decreased in FHs74 cells. These potential downstream genes were significantly correlated with levels of miR-223 or NFIA in primary NEC tissues. Overexpression of miR-223 significantly increased apoptosis of Caco-2 and FHs74 cells, while proliferation of FHs74 was inhibited. These results suggest that upon binding with NFIA, miR-223 regulates functional effectors in pathways of apoptosis, cell proliferation, G protein signaling, inflammation, and smooth muscle contraction. The miR-223/NFIA axis may play an important role in the pathophysiology of NEC by enhancing inflammation and tissue damage.

R4 RGS proteins suppress engraftment of human hematopoietic stem/progenitor cells by modulating SDF-1/CXCR4 signaling.

Homing and engraftment of hematopoietic stem/progenitor cells (HSPCs) into the bone marrow (BM) microenvironment are tightly regulated by the chemokine stromal cell-derived factor-1 (SDF-1) and its G-protein-coupled receptor C-X-C motif chemokine receptor 4 (CXCR4), which on engagement with G-protein subunits, trigger downstream migratory signals. Regulators of G-protein signaling (RGS) are GTPase-accelerating protein of the Gα subunit and R4 subfamily members have been implicated in SDF-1-directed trafficking of mature hematopoietic cells, yet their expression and influence on HSPCs remain mostly unknown. Here, we demonstrated that human CD34+ cells expressed multiple R4 RGS genes, of which RGS1, RGS2, RGS13, and RGS16 were significantly upregulated by SDF-1 in a CXCR4-dependent fashion. Forced overexpression of RGS1, RGS13, or RGS16 in CD34+ cells not only inhibited SDF-1-directed migration, calcium mobilization, and phosphorylation of AKT, ERK, and STAT3 in vitro, but also markedly reduced BM engraftment in transplanted NOD/SCID mice. Genome-wide microarray analysis of RGS-overexpressing CD34+ cells detected downregulation of multiple effectors with established roles in stem cell trafficking/maintenance. Convincingly, gain-of-function of selected effectors or ex vivo priming with their ligands significantly enhanced HSPC engraftment. We also constructed an evidence-based network illustrating the overlapping mechanisms of RGS1, RGS13, and RGS16 downstream of SDF-1/CXCR4 and Gαi. This model shows that these RGS members mediate compromised kinase signaling and negative regulation of stem cell functions, complement activation, proteolysis, and cell migration. Collectively, this study uncovers an essential inhibitory role of specific R4 RGS proteins in stem cell engraftment, which could potentially be exploited to develop improved clinical HSPC transplantation protocols.

Brain-derived neurotrophic factor rescues and prevents chronic intermittent hypoxia-induced impairment of hippocampal long-term synaptic plasticity.

Obstructive sleep apnea (OSA) is a common sleep and breathing disorder characterized by repeated episodes of hypoxemia. OSA causes neurocognitive deficits including perception and memory impairment but the underlying mechanisms are unknown. Here we show that in a mouse model of OSA, chronic intermittent hypoxia treatment impairs both early- and late-phase long-term potentiation (LTP) in the hippocampus. In intermittent hypoxia-treated mice the excitability of CA1 neurons was reduced and hippocampal brain-derived neurotrophic factor (BDNF) was down-regulated. We further showed that exogenous application of BDNF restored the magnitude of LTP in hippocampal slices from hypoxia-treated mice. In addition, microinjection of BDNF into the brain of the hypoxic mice prevented the impairment in LTP. These data suggest that intermittent hypoxia impairs hippocampal neuronal excitability and reduces the expression of BDNF leading to deficits in LTP and memory formation. Thus, BDNF level may be a novel therapeutic target for alleviating OSA-induced neurocognitive deficits.

Serum levels of heavy metals in childhood eczema and skin diseases: friends or foes.

The incidence of eczema has been increasing in developed countries. Environmental and hygiene factors have been incriminated. Although air and food pollution with heavy metals have been considered as possible culprits, these factors have never been investigated in Hong Kong. To evaluate if quality of life and eczema severity are associated with abnormal serum levels of six common heavy metals, namely, cadmium, lead, mercury, selenium, copper and zinc. Serum or whole blood was taken for measurement of six heavy metals from patients referred to the pediatric dermatology clinic. Eczema severity (SCORAD and NESS) and quality of life (CDLQI) were recorded. A total of 110 patients with eczema and 41 patients with miscellaneous skin conditions were recruited. Serum levels of the six heavy metals were generally within the upper limits of local reference ranges. Zinc levels were below the lower reference limit of 9.4 mum in 66 patients with eczema (60%) and 22 non-eczema patients (53%). Forty-four patients with eczema (40%) and 24 (58%) in non-eczema group had low copper levels. In eczema patients, lead levels were generally within normal limits but their levels were positively correlated with poor quality of life (CDLQI: r = 0.22 and p < 0.05), disease severity (objective SCORAD: r = 0.33 and p < 0.005; NESS: 0.20, p < 0.05), eosinophil count and log-transformed IgE. Copper/zinc ratio also correlated with NESS and CDLQI and was generally higher than non-eczema skin diseases. Our findings help reassure parents that levels of heavy metals generally do not exceed the local reference ranges for toxicity. However, lead levels have significant correlations with disease severity, quality of life and atopy. Low zinc and copper levels are commonly found in pediatric skin diseases and their significance needs to be determined.

A Prospective Cohort Study of Fecal miR-223 and miR-451a as Noninvasive and Specific Biomarkers for Diagnosis of Necrotizing Enterocolitis in Preterm Infants.

OBJECTIVE: The objective of this study is to evaluate the usefulness of fecal microRNA (miR)-223 and miR-451a, as novel noninvasive biomarkers for early diagnosis of necrotizing enterocolitis (NEC) in preterm infants. METHODS: Among the top-listed target miRNAs in our previous differential microarray analysis, miR-223 and miR-451a were quantified in a pilot validation case-controlled study (NEC vs. non-NEC/nonsepsis infants; n = 6 in each group). A definitive prospective cohort study (n = 218) further assessed their clinical usefulness as noninvasive and specific diagnostic biomarkers. Fecal calprotectin was quantified in parallel for comparison. RESULTS: Of 43 proven NEC cases in the cohort study, 24 (55.8%) had fecal samples recovered within the first 3 days of clinical presentation. Fecal miRNA-223 (10.5 fold), miR-451a (4.5 fold), and calprotectin (2.1 fold) concentrations were significant higher in NEC compared with the non-NEC group (p < 0.009). Accepting a minimum sensitivity of 0.75, the positive predictive values (PPVs) ranged between 0.19 and 0.20. Combining fecal biomarkers and CRP (Day 1) could marginally increase the PPVs (0.31-0.34) but adversely lowered the sensitivity (0.54-0.63). CONCLUSIONS: Although fecal miRNA biomarkers and calprotectin concentrations were significantly higher in the NEC group, the considerable overlapping of concentrations between groups and low recovery of stool specimens within 72 h of clinical presentation rendered fecal noninvasive tests of limited clinical value in guiding diagnosis of NEC during the acute phase. A further study is underway to evaluate their roles in surveillance for predicting high-risk premature infants developing NEC.

CD9 blockade suppresses disease progression of high-risk pediatric B-cell precursor acute lymphoblastic leukemia and enhances chemosensitivity.

CD9 has been implicated in cancer progression but its prognostic relevance and therapeutic potential in B-cell precursor acute lymphoblastic leukemia (BCP-ALL) are largely unknown. In a cohort of pediatric BCP-ALL patients, we found that CD9+ cases had a significantly lower 5-year relapse-free survival rate than CD9- cases. Multivariate analysis demonstrated that CD9 positivity independently predicted inferior survival outcomes, and could be applied with established prognostic features, including prednisone response and cytogenetic status, to refine patient stratification. Administration of CD9 antibody substantially suppressed disease progression in NOD/SCID mice xenografted with CD9+ cell lines and primary leukemic blasts from patients with high-risk and refractory BCP-ALL, without compromising hematopoietic stem cell engraftment. Combination of anti-CD9 with conventional chemotherapy further reduced leukemic burden and prolonged animal survival. Mechanistically, CD9 blockade inhibited leukemic cell proliferation, induced G0/G1 cell cycle arrest, activated p38, and enhanced chemotherapeutic agent-induced apoptosis. Further, CD9 physically interacted with integrin very late antigen-4, regulated affinity to vascular cell adhesion molecule-1, and was involved in leukemia-stroma interaction. Collectively, our study established CD9 as a new prognostic marker, validated the preclinical efficacy of CD9 antibody, and laid the foundation for clinical development of CD9-targeted therapy for high-risk and refractory pediatric BCP-ALL.

Epidemiology and clinical presentations of human coronavirus NL63 infections in hong kong children.

Human coronavirus NL63 (HCoV-NL63) has been found in children presenting with respiratory tract infections (RTIs). However, the epidemiology and clinical course of this newly identified virus have not been fully elucidated. This study investigated the epidemiology, seasonality, and clinical features of HCoV-NL63 in Hong Kong children. This study consisted of two cohorts of children hospitalized in a university-affiliated teaching hospital. In the 12-month retrospective part of the study, reverse transcription-PCR was used to detect HCoVs in nasopharyngeal aspirates (NPAs). Positive samples were sequenced to confirm the identity of the virus and to determine its phylogenetic relationship with the HCoV-NL63 strains found elsewhere. The second part covered a subsequent 12-month period in which patients were prospectively recruited. Altogether, 1,981 and 1,001 NPA specimens were studied in 2005-2006 and 2006-2007, respectively. Seventy-four (2.5%) HCoV isolates were identified and consisted of 17 (0.6%) HCoV-NL63 isolates, 37 (1.2%) HCoV-OC43 isolates, 14 (0.5%) HCoV-HKU1 isolates, and 6 (0.2%) HCoV-229E isolates. HCoV-NL63 infection was more common in 2006-2007 than 2005-2006 (1.2% and 0.3%, respectively; P = 0.006). From 2005 to 2007, the peak season for HCoV-NL63 infection was in September-October, which was earlier than the peak for HCoV-OC43 infections (December-January). HCoV-NL63-infected patients were younger and more likely to have croup, febrile convulsions, and acute gastroenteritis. The majority of local HCoV-NL63 isolates were phylogenetically closely related to those found in Belgium and The Netherlands. In conclusion, HCoV-NL63 is an important yet uncommon virus among our hospitalized children with acute RTIs.

Big snake, small snake: which wound is worse when bitten?

UNLABELLED: Snakebites in children and teenagers are relatively uncommon in the metropolitan city of Hong Kong. They are rarely fatal but may cause significant morbidity and fear. We report two cases of snakebites to illustrate that the spectrum of morbidity is independent of the size of the snakes. A 7-year-old boy was bitten in successions by a green snake. Envenomation occurred at the second bite site. He developed local and systemic signs that were promptly relieved with anti-venom therapy at the intensive care unit. An 18-year-old girl was bitten by a large python but only sustained minor local soft tissue injuries. This report serves to alert the public that snake may bite in successions and envenomation may occur with the subsequent bite. CONCLUSION: A small snake may be venomous and a large snake may not be. Avoidable risk factors associated with snakebites (such as avoiding areas known to harbour snakes in the evening in summer and autumn and wearing protective footwear) are highlighted.