Prevalence of respiratory and atopic disorders in Chinese schoolchildren.

Background: Epidemiological surveys have shown that the prevalence of asthma in the Asian population is relatively low. Within the Chinese population, schoolchildren from Hong Kong were found to have the highest rate of asthma.

Objective: To compare the prevalence of respiratory and atopic disorders, and to assess the role of atopy in the development of asthma, in Chinese schoolchildren from Hong Kong, Beijing and Guangzhou.

Deceptive hyperbilirubinaemia in a newborn with familial lipoprotein lipase deficiency.

A rare case of familial lipoprotein lipase (LPL) deficiency in a Chinese newborn who presented with severe hyperbilirubinaemia is described. The falsely high serum bilirubin concentration was subsequently found to be a laboratory analytical error caused by interference of optical measurement of the lipaemic serum. Hypertriglyceridaemia and chylomicronaemia could be safely and effectively controlled by a fat-restricted diet using either modified elementary milk formula fortified with protein, calories and minerals, or the commercially available special milk formula such as Monogen or Portagen.

Haematopoietic stem and progenitor cells in human term and preterm neonatal blood.

Background And Objectives: Whilst cord blood (CB) contains a significant number of haematopoietic stem and progenitor cells suitable for bone marrow transplantation, levels of these cells are very low in the adult circulation. In previous studies, we demonstrated that stem and progenitor cells are present in neonatal blood (NB) and reported the first sibling transplant using a combination of CB and NB for a patient with beta-thalassaemia major. However, our preliminary data showed that the number of CD34+ cells decreased rapidly in the peripheral blood of neonates soon after birth.

Platelet-derived growth factor enhances ex vivo expansion of megakaryocytic progenitors from human cord blood.

Infusion of ex vivo expanded megakaryocytic (MK) progenitor cells is a strategy for shortening the duration of thrombocytopenia after haematopoietic stem cell transplantation. The cell dose after expansion has emerged as a critical factor for achieving the desired clinical outcomes. This study aimed to establish efficient conditions for the expansion of the MK lineage from enriched CD34(+) cells of umbilical cord blood and to investigate the effect of platelet-derived growth factor (PDGF) in this system.

Oxygen consumption and resting energy expenditure during phototherapy in full term and preterm newborn infants.

Objectives: To determine the effect of phototherapy on the oxygen consumption and resting energy expenditure of term and preterm newborn infants.

Methods: A total of 202 infants (gestation 30-42 weeks; body weight 1270-4100 g) requiring phototherapy for the treatment of neonatal hyperbilirubinaemia were enrolled in a randomised crossover study. In random sequence, the oxygen consumption and resting energy expenditure were measured twice in each infant by indirect calorimetry, once at the end of six hours of continuous phototherapy and once after a control period of at least six hours without phototherapy.

Changes of leptin and metabolic hormones in preterm infants: a longitudinal study in early postnatal life.

Objectives: Very little is known concerning the physiological role of leptin and growth in the early postnatal period and the association of leptin with other metabolic hormones in preterm infants. This study aims to investigate these relationships, and to explore the longitudinal and dynamic profile of leptin and metabolic hormones including insulin, ACTH, cortisol and FT4 in this category of patient. We also postulate that a rapid increase in body weight and body mass index in the first few weeks of life may be associated with a corresponding increase in serum leptin if the 'adipoinsular axis' is active at this stage.

Temporal relationship between air pollution and hospital admissions for asthmatic children in Hong Kong.

Background: Many epidemiological studies have shown positive association between respiratory health and current levels of outdoor air pollution in Europe and America.

Objective: The aim of this study was to investigate the association between air pollution and the number of childhood admissions for asthma in Hong Kong.

Methods: Daily counts of childhood admission for asthma to a large teaching Hospital were obtained from the computerized database for the period 1993-1994.

Platelet-derived growth factor enhances granulopoiesis via bone marrow stromal cells.

Platelet-derived growth factor (PDGF), a growth factor for connective tissue cells, stimulates erythropoiesis and megakaryocytopoiesis in vitro but the effect of PDGF on granulocyte proliferation remains unknown. The effect of the recombinant human PDGF-BB isoform on granulopoiesis was investigated in this study. The results show that PDGF significantly stimulated murine colony-forming unit-granulocyte-monocyte (CFU-GM) proliferation in a dose-dependent manner (1 to 100 ng/mL) using murine bone marrow cells (n = 4).

Randomised controlled study of oral erythromycin for treatment of gastrointestinal dysmotility in preterm infants.

Aim: To evaluate the effectiveness of oral erythromycin as a prokinetic agent for the treatment of moderately severe gastrointestinal dysmotility in preterm very low birthweight infants.

Methods: A prospective, double blind, randomised, placebo controlled study in a tertiary referral centre of a university teaching hospital was conducted on 56 preterm infants (< 1500 g) consecutively admitted to the neonatal unit. The infants were randomly allocated by minimisation to receive oral erythromycin (12.

Dextran sedimentation in a semi-closed system for the clinical banking of umbilical cord blood.

Background: The results of current processing procedures for reducing volume and recovering HPCs from umbilical cord blood (UCB) before cryopreservation vary.

Study Design And Methods: Dextran was added to bags containing UCB, followed by sedimentation for 30 minutes. The processed UCB was then frozen.

Hyperoxia-induced lung injury in premature rat: description of a suitable model for the study of lung diseases in newborns.

Objective: To provide suitable animal model (hyperoxia-induced premature rat lung damage) for research of bronchopulmonary dysplasia (BPD) and to better understand pathogenesis of BPD and look for effective drugs to prevent and treat BPD.

Methods: Rat litters delivered prematurely at 21-day gestation by hysterotomy. Vigorous resuscitation at birth resulted in a high survival rate.

Refractory hypotension in preterm infants with adrenocortical insufficiency.

Five preterm, very low birthweight infants with severe hypotension and adrenocortical insufficiency are described. The profound hypotension was resistant to volume expansion and inotrope treatment, but responded promptly to corticosteroid treatment. A human corticotrophin releasing hormone (hCRH) test performed before corticosteroid treatment showed adequate pituitary response, and the endocrine dysfunction was identified at the adrenal level.

Hepatic iron storage in very low birthweight infants after multiple blood transfusions.

Objective: To investigate the effect of multiple blood transfusions on hepatic iron storage in preterm, very low birthweight (VLBW) infants.

Methods: Seventeen VLBW infants who died within the first six months of life and underwent postmortem examination were studied. Serum ferritin, iron, and total iron binding capacity were measured within the week before the infants' death.

Normal pulse oximeter reading in a cyanotic infant.

A newborn infant who presented with central cyanosis was found to have hereditary methaemoglobinaemia. The pulse oximeter readings and physical findings were incompatible. Clinical assessment remains an important part in the management of such cases.

Expression of interleukin (IL) 1 type I and type II receptors in megakaryocytic cells and enhancing effects of IL-1beta on megakaryocytopoiesis and NF-E2 expression.

Megakaryocytopoiesis is regulated by thrombopoietin (TPO) and cytokines such as interleukin 3 (IL-3), IL-6 and IL-11. This study investigated the in vitro effects of IL-1beta on megakaryocytopoiesis and the expression of IL-1 type I and type II receptors (IL-1 RI and RII) on mega-karyocytic cell lines and primary cells. Our results demonstrated that IL-1beta alone or in combination with TPO induced megakaryocyte colony forming units (CFU-MK) from murine and human haematopoietic cells.

Recurrent and novel mutations of GCDH gene in Chinese glutaric acidemia type I families.

Glutaric acidemia type I is caused by mutations of the glutaryl-CoA dehydrogenase (GCDH) gene resulting in loss of GCDH enzyme activity. Patients present with progressive dystonia and lesions in basal ganglia. Dietary treatment, when instituted from the early neonatal period, markedly reduces dystonia and morbidity.

Leptin and metabolic hormones in preterm newborns.

Aim: To investigate the inter-relation between leptin and other metabolic hormones in preterm and term infants and to explore whether a functional "adipoinsular axis" might exist in preterm newborns.

Methods: A total of 140 preterm and term newborns were prospectively recruited and categorised according to gestation length. Blood samples were taken at 24 hours (day 1), and on day 4-5 of life.

Leptin and metabolic hormones in infants of diabetic mothers.

Aims: To investigate the effect of maternal diabetes on leptin in term newborns and to determine whether leptin correlates with insulin and its associated biochemical parameters in support of the hypothesis that a functional "adipoinsular axis" might exist at this stage of development.

Methods: A total of 116 term newborns were prospectively enrolled and categorised into three groups: 44 were infants of non-diabetic mothers (control group C); 41 were infants born to mothers with gestational diabetes on dietary treatment (group D); and 31 were infants born to mothers with gestational or pregestational diabetes on insulin treatment (group I).

Results: No significant difference in serum leptin was observed between the three groups; the results of the study population were therefore pooled and analysed.

Central nervous system candidiasis in preterm infants: limited value of biochemical markers for diagnosis.

Two rare cases of isolated central nervous system (CNS) candidiasis in preterm infants have been diagnosed in a tertiary neonatal centre over the past 6 years. Despite the life-threatening nature of the disease, biochemical infection markers were not useful for the early identification of localized fungal infection. Because the infection was likely to have been blood borne, we postulated that the initial fungal load was probably low and that the organisms were rapidly eliminated from the circulation after a few had been deposited in the CNS.

Mercury intoxication presenting with tics.

A 5 year old Chinese boy presented with recurrent oral ulceration followed by motor and vocal tics. The Chinese herbal spray he used for his mouth ulcers was found to have a high mercury content. His blood mercury concentration was raised.

Pneumocystis carinii pneumonia in an immunocompetent infant with congenital cytomegalovirus infection.

The case of a term infant with congenital cytomegalovirus (CMV) infection who developed Pneumocystis carinii pneumonia (PCP) at 4 months of age is reported. Our patient suffered from severe malnutrition and zinc deficiency secondary to necrotizing enterocolitis since the age of 2 months. There was no evidence of human immunodeficiency virus infection.

Cerebral blood flow during vasovagal syncope induced by active standing or head up tilt.

Background: Vasovagal syncope is usually associated with a sudden drop of blood pressure and/or heart rate. However, occasionally the symptoms of syncope induced by orthostatic stress testing are not associated with obvious haemodynamic changes. The mechanisms of syncope in these patients are not clear.

Early onset of hypernatraemic dehydration and fever in exclusively breast-fed infants.

Five cases of moderately severe hypernatraemic dehydration were identified within a 5-month period between two regional hospitals in Hong Kong. Unlike previous reported cases, these exclusively breast-fed infants presented with the unusual triad of fever, absence of overt signs of dehydration and within the first week of life. Three of the cases also had high serum bilirubin concentrations at presentation.