Biomedical subjects

S M Chan

Publications and source records attributed to S M Chan.

At least 19 recordsLinked to original sources

PubMed2006

Immuno-prophylaxis of babies borne to hepatitis B carrier mothers.

OBJECTIVES: To examine the efficacy of current hepatitis B immuno-prophylaxis and estimate the prevalence of S-mutant infections among local newborn babies. DESIGN: Prospective study. SETTING: Regional hospital, Hong Kong. PATIENTS: A total of 137 newborn babies delivered between the period of November 2000 and 30 June 2001 inclusive, whose mothers were chronic hepatitis B surface antigen carriers. RESULTS: Of the 121 infants who were followed up for 12 months, three were found to be chronic hepatitis B virus carriers, giving a vertical transmission rate of 2.5%. One (0.8%) was suspected to be infected by the S-mutant. All the three hepatitis B virus carrier babies were born to mothers with hepatitis B e antigen, but none to the eight mothers suspected to have S-mutants. Of 119 (98.3%) infants who developed hepatitis B surface antibody upon follow-up at 12 months, 35 were found to have hepatitis B e antigen at birth. All were born to hepatitis B e antigen-positive mothers. Only three of the 35 babies were found to be hepatitis B virus carriers. Most babies lost the hepatitis B e antigen by 6 months of age; only the infected babies had the antigen persisting at 1 year of age. The non-infected infants' hepatitis B e antigen is likely transplacental. CONCLUSIONS: Our hepatitis B virus prophylaxis programme was effective at preventing perinatal infection and the non-infected infants' hepatitis B e antigen was likely transplacental.

Carrier State↗

PubMed2005

Influences of salinity on the biokinetics of Cd, Se, and Zn in the intertidal mudskipper Periophthalmus cantonensis.

The biokinetics (aqueous uptake, dietary assimilation, and elimination) of Cd, Se, and Zn in the intertidal mudskipper, Periophthalmus cantonensis, were examined at different acclimated salinities using the radiotracer technique. The dietary assimilation efficiency from ingested radiolabeled polychaetes was the highest for Se (32-40%), followed by Zn (5-7%) and Cd (2-3%), and was not influenced by salinity within a range of 10-30 psu. Uptake from the dissolved phase typically exhibited a linear pattern within the first 12 h of exposure, followed by a second slower uptake. The highest concentration factor (CF) was found for Zn, followed by Cd and Se. Differences in salinity did not significantly affect the CF of the three metals within the first 12 h, but the CFs were significantly higher at lower salinities (10-20 psu) than at the highest salinity (30 psu) by the end of 48 h exposure. Because the degrees to which the uptake of Se (a metalloid) and Cd/Zn were affected by salinity were comparable, we concluded that metal speciation as a result of salinity change was not important in leading to a change in metal CF. Physiological changes may be responsible for the increasing uptake at lowered salinity. The elimination rates of the three metals (0.01-0.06 d(-1)) were not significantly affected by salinity, but Se was eliminated at a faster rate following aqueous uptake than following dietary ingestion. There was no consistent influence of exposure routes on Cd and Zn elimination. The accumulated Cd was mainly associated with the gut, whereas the muscle was the dominant target site for Se and Zn accumulation.

Animals↗

PubMed2005

Aspartic acid scanning mutation analysis of a goldfish growth hormone-releasing hormone (GHRH) receptor specific to the GHRHsalmon-like peptide.

Growth hormone-releasing hormone (GHRH) plays a pivotal role in the regulation of growth. The study of goldfish GHRH and its receptor is of particular interest as it is so far the only animal model in which two forms of GHRH-like (catfish-like and salmon-like) peptides coexist, and these peptides share only 30-40% of amino acid sequence identities with their mammalian counterparts. For these reasons, we have previously characterized a goldfish GHRH receptor, which is specific for a synthetic carp GHRH-like peptide. In this study, we investigated the structure-function relationships between the receptor and various ligands. Interestingly, among the two endogenous goldfish GHRH-like peptides, only the GHRHsalmon-like peptide was able to stimulate CHO cells transfected with the goldfish GHRH receptor. When the receptor was challenged by GHRHsalmon-like peptide either continuously for 45 min or periodically at 45-min intervals, mild homologous desensitization was observed. To determine whether the negatively charged residues of the receptor are responsible for discriminating GHRHsalmon-like from GHRHcatfish-like, 10 aspartic acid residues residing in the N-terminal ectodomain and the second exoloop were individually mutated to alanine by site-directed mutagenesis. Among these 10 mutants, four of them (D66A, D122A, D190A, and D196A) were defective as indicated by both cAMP assays and extracellular acidification rate measurements. Confocal microscopic studies showed that the D66A and D122A mutants, but not the D190A and D196A mutants, were expressed properly at the plasma membrane. Collectively, these results suggest that aspartic acid residues at positions 66 and 122 are critical for the interaction between the goldfish GHRH receptor and its endogenous ligands.

Animals↗

PubMed2005

Bone mineral density and calcium metabolism of Hong Kong Chinese postpartum women--a 1-y longitudinal study.

OBJECTIVE: This paper reports longitudinal changes in bone mineral density (BMD), calcium homeostasis and dietary calcium intake in a group of Hong Kong breastfeeding women during the first year postpartum. DESIGN AND SUBJECTS: Nine mothers who breastfed exclusively or almost exclusively for at least 3 months and 14 formula feeding mothers aged 20-40 y were interviewed after delivery, 2 and 6 weeks, 3, 6 and 12 months postpartum. BMD at L2-L4 lumbar spine (LS), trochanter (Tro) and femoral neck (FN), serum intact parathyroid hormone (iPTH), serum bone-specific alkaline phosphatase (b-ALP), urinary deoxypyridinoline (Dpd), serum and urinary calcium (Ca) and phosphorus (P) and dietary intake of macronutrients were assessed. RESULTS: Compared to the formula feeding group, BMD assessed at LS, Tro and FN decreased significantly in the breastfeeding group over the first 6 months, with rebound to approximate baseline values at 12 months for the latter two sites. Serum iPTH increased in both groups, whereas serum b-ALP was consistently higher in the breastfeeders. Urinary Ca and P excretion decreased early postpartum in both groups, but the breastfeeders had higher excretion at 3 and 6 months. Breastfeeding mothers consumed significantly more Ca than the formula feeding mothers in the early postpartum. CONCLUSIONS: Increased calcium requirement during early lactation is affected through mobilisation of bone and renal calcium conservation. Bone mineral loss during lactation is temporary. Further studies are warranted to investigate the effects of diet and other hormonal factors on the calcium homeostasis during lactation.

Adult↗

PubMed2003

Preconcentration using diethylenetriaminetetraacetic acid-functionalized polysiloxane (DETAP) for determination of molybdenum(VI) in seawater by ICP-OES.

This paper reports a new method for preconcentration and separation of trace amounts of molybdenum in seawater samples prior to determination by inductively coupled plasma-atomic emission spectroscopy (ICP-OES). Diethylenetriaminetetraacetic acid-functionalized polysiloxane (DETAP) was synthesized by carboxymethylation of amino groups on triamine immobilized polymer, which was prepared by modification of 3-chloropropylpolysiloxane with diethylenetriamine. The resulting polysiloxane is highly selective and efficient in chelating Mo(VI) at trace levels. It can be used as a column packing material. The polysiloxane column can be reused over ten times without losing its original properties, so it is suitable for preconcentration of molybdenum species in seawater samples before determination. The parameters governing the characteristics of polysiloxane for adsorption of Mo(VI) were investigated. These include the effect of pH, amount of polysiloxane, equilibrium time, adsorption isotherm, maximum adsorption capacity, interfering ions, flow rate, capacity for reuse, and desorption. The precision of the preconcentration method, calculated as the relative standard deviation of seawater samples, was 3%. The preconcentration factor was 100. The detection limit, defined as 3 times the standard deviation of five replicate measurements of the blank sample at pH 3, was 0.17 microg L(-1). Measurement results for standard reference materials were in good agreement with the certified values [(CRMs), NASS-2 Seawater (Open Ocean) and CASS-2 Seawater (Coastal)].

Chelating Agents↗

PubMed2003

Comparison of dioxin and PCB concentrations in human breast milk samples from Hong Kong and the Netherlands.

The adverse effects of dioxins and polychlorinated biphenyls (PCBs) on human health are of increasing concern. These lipophilic compounds are concentrated through the food chain and are present in human milk. This study compares PCB levels in human milk samples from Hong Kong and Dutch mothers. Ten breast milk samples from Hong Kong and 10 from the Netherlands were collected during home visits between 2 and 6 weeks postpartum. Total toxic equivalence (TEQ) of dioxin and PCBs were determined using the DR-CALUX(R) bioassay. The total dioxin and PCB levels in breast milk samples for Hong Kong ranged from 3.1 to 29.9 pg TEQ g(-1) lipid and for the Netherlands from 8.9 to 89.5 pg TEQ g(-1) lipid. Despite Hong Kong's high degree of industrialization, the levels of dioxin and PCBs were fourfold lower in the Hong Kong than in the Dutch samples. This may be due to a lower dietary intake of dioxins and PCBs in Hong Kong because of lower background levels of these contaminants or to different food habits.

Adult↗

PubMed2001

Complete genome analysis of the mandarin fish infectious spleen and kidney necrosis iridovirus.

The nucleotide sequence of the infectious spleen and kidney necrosis virus (ISKNV) genome was determined and found to comprise 111,362 bp with a G+C content of 54.78%. It contained 124 potential open reading frames (ORFs) with coding capacities ranging from 40 to 1208 amino acids. The analysis of the amino acid sequences deduced from the individual ORFs revealed that 35 of the 124 potential gene products of ISKNV show significant homology to functionally characterized proteins of other species. Some of the putative gene products of ISKNV showed significant homologies to proteins in the GenBank/EMBL/DDBJ databases including enzymes and structural proteins involved in virus replication, transcription, protein modification, and virus-host interaction. In addition, one major repeated sequence showing significant homology to the Red Sea bream iridovirus (RSIV) genome was identified. Based on the information obtained from biological properties (including histopathology, tissue tropisms, natural host range, and geographic distribution), physiochemical and physical properties, and genome analysis, we suggest that ISKNV, RSIV, sea bass iridovirus, grouper iridovirus, and African lampeye iridovirus may belong to a new genus of the Iridoviridae family and are tentatively referred to as cell hypertrophy iridoviruses.

Amino Acid Sequence↗

PubMed2001

Bacterial expression of the shrimp molt-inhibiting hormone (MIH): antibody production, immunocytochemical study and biological assay.

Molting in shrimp is controlled by the molt-inhibiting hormone (MIH) and ecdysone. MIH inhibits the synthesis of ecdysone in the Y-organ, resulting in molt suppression; it is a neuropeptide member belonging to the eyestalk CHH/MIH/GIH family. The cloning of MIH (formerly MIH-like) of the shrimp Metapenaeus ensis has been reported in a previous study. To obtain a large quantity of fusion protein for antibody production and biological assay, the cDNA encoding the shrimp MIH was inserted into the pRSET bacterial expression vector. His-tagged fusion protein was produced and purified by an Ni2+-charged affinity column. Polyclonal antibody to rMIH was subsequently obtained by immunizing rabbits with purified recombinant proteins. Results from Western blot analysis indicated that the antibody was specific. Furthermore, results from immunocytochemical analysis showed that specific cells in three different clusters of the X-organ, the sinus gland and the axonal tract of the eyestalk contain MIH. To test for the molt-inhibiting activity of rMIH, shrimp at intermolt stage were injected with rMIH and the molt cycle duration of the injected shrimp was monitored. A significant increase in molt cycle duration was recorded for the shrimp injected with the recombinant protein.

Amino Acid Sequence↗

PubMed2001

The shrimp FAMeT cDNA is encoded for a putative enzyme involved in the methylfarnesoate (MF) biosynthetic pathway and is temporally expressed in the eyestalk of different sexes.

Methylfarnesoate (MF), an analogue of the insect juvenile hormone III, has been implicated to play a vital role in the regulation of the growth and reproductive development in crustaceans. Farnesoic acid O-methyltransferase (FAMeT) is the key enzyme involved in catalyzing the final step in the MF biosynthetic pathway. In this study, we report the cloning and characterization of the cDNA encoding the putative FAMeT of the shrimp Metapenaeus ensis. FAMeT comprises 280 amino acid residues with a predicted molecular weight of 32kDa. The predicted putative FAMeT protein reveals a high degree of structural conservation of FAMeT with the lobsters. It shares 79 and 70% sequence identities with the putative FAMeTs of Homarus americanus and Panulirus interruptus, respectively. As revealed by the Southern blot analysis and genomic PCR, only one gene exists in the shrimp genome and the gene is uninterrupted in the coding region. The shrimp FAMeT mRNA is widely distributed in many tissues with the highest expression level observed in the central nervous system. A constant level of FAMeT expression is recorded in the ventral nerve cord of the juveniles and the mature females during the reproductive cycle. Unlike the ventral nerve cord, the eyestalk of the juvenile male, but not the female, expresses FAMeT. Further study shows that the eyestalk of the mature female expresses FAMeT during all stages of ovarian maturation. We speculate that FAMeT may be important for the regulation of eyestalk neuropeptides. This is the first extensive study on the molecular characterization, structural analysis and expression of the crustacean FAMeT.

Amino Acid Sequence↗

PubMed2001

Postnatal iron status of Hong Kong Chinese women in a longitudinal study of maternal nutrition.

OBJECTIVE: To report postnatal iron nutritional status of Hong Kong Chinese women during the first 6 months postpartum. DESIGN AND SUBJECTS: A longitudinal study examining postnatal calcium and iron status of Hong Kong Chinese breastfeeding and formula-feeding women was conducted during 1998. Postpartum women aged 20-40 y, with no bone or blood disorders were recruited and interviewed at 0 (baseline), 2, 6 weeks, 3 and 6 months postpartum. Dietary intake was assessed by a 3 day dietary record and cross checked by a 24 h recall. Complete blood count and serum ferritin level were measured to assess anaemia and iron status. In this report, subjects were divided into an anaemic group (haemoglobin level < 10 g/dl) and a non-anaemic group (haemoglobin level > or = 10 g/dl) according to baseline haemoglobin levels. RESULTS: At baseline, 13/47 (27.7%) subjects were anaemic. Two of these 13 anaemic subjects were still anaemic at 3 and 6 months postpartum. Anaemic subjects showed significantly (P < 0.01) greater amounts of blood loss and a higher rate of primary postpartum haemorrhage than the non-anaemic subjects. Daily food intake and dietary nutrient intake did not differ significantly between the two groups. During the first 6 weeks postpartum, subjects in both groups consumed more poultry and egg, and comparable amounts of meat, compared with women in the Hong Kong general population. Iron and vitamin C intakes for the majority of subjects reached 60% of the US Recommended Daily Allowances. Regression analysis suggested that the rate of change in haemoglobin level in the first 6 weeks postpartum was positively correlated with baseline MCV level and serum ferritin level, but negatively correlated with baseline haemoglobin level. CONCLUSIONS: Blood loss at delivery is an important factor for postpartum anaemia. Postnatal recovery of iron status of this group of women appeared to be more related to physiological factors than to dietary factors. The role of diet as well as other physiological changes in postpartum women requires further investigation. Finding ways to minimise blood loss at delivery could be the most practical strategy to reduce the rate of postpartum anaemia. SPONSORSHIP: CSM was supported by a research studentship from the Research Grants Council, Hong Kong.

Adult↗

PubMed2001

Structural and functional identification of the pituitary adenylate cyclase-activating polypeptide receptor VPAC2 from the frog Rana tigrina rugulosa.

Recently, a frog pituitary adenylate cyclase-activating polypeptide (PACAP)/vasoactive intestinal peptide (VIP) receptor (fPVR) has been characterized, and interestingly, this receptor exhibits characteristics of both mammalian PACAP type II receptors VPAC(1)R and VPAC(2)R. In order to investigate the receptors responsible for mediating the actions of VIP and PACAP in amphibians, in this report, a frog VPAC(2) receptor (fVPAC(2)R) cDNA was isolated. fVPAC(2)R shares 47.7, 46.9 and 62.5% amino acid sequence identity with fPVR, human VPAC(1)R and human VPAC(2)R respectively. Functionally, fVPAC(2)R, when expressed in CHO cells, was responsive to both frog peptides including VIP, PACAP38 and PACAP27 where the EC(50) values of these peptides in intracellular cAMP production were 0.15, 0.18 and 0.16 microM respectively. The pharmacological profiles of human peptides (VIP, PACAP38 and peptide histidine methionine) to stimulate frog and human VPAC(2)Rs were compared, and it was found that these peptides could only activate the frog receptor at micromolar concentrations. fVPAC(2)R was found to be widely distributed in various peripheral tissues as well as several regions of the brain. The presence of the receptor transcripts suggests the functional roles of the receptor in mediating the actions of PACAP and/or VIP in these tissues. As VIP and particularly PACAP27 are highly conserved peptides in vertebrate evolution, comparative studies of these peptides and their receptors in non-mammalian vertebrates should provide clues to better understand the physiology of these important peptides in human and other vertebrates.

Amino Acid Sequence↗

PubMed2000

Role of antigen-presenting cells in mediating tolerance and autoimmunity.

The mechanisms that determine whether receptor stimulation leads to lymphocyte tolerance versus activation remain poorly understood. We have used rat insulin promoter (RIP)-gp/P14 double-transgenic mice expressing the lymphocytic choriomeningitis virus (LCMV) glycoprotein (gp) on pancreatic beta-islet cells together with T cells expressing an LCMV-gp-specific T cell receptor to assess the requirements for the induction of autoimmunity. Our studies have shown that administration of the gp peptide gp33 leads to the activation of P14-transgenic T cells, as measured by the upregulation of activation markers and the induction of effector cytotoxic activity. This treatment also leads to expansion and deletion of P14 T cells. Despite the induction of cytotoxic T lymphocyte activity, peptide administration is not sufficient to induce diabetes. However, the administration of gp peptide together with an activating anti-CD40 antibody rapidly induces diabetes. These findings suggest that the induction of tolerance versus autoimmunity is determined by resting versus activated antigen-presenting cells.

Animals↗

PubMed2000

Molecular characterization of an additional shrimp hyperglycemic hormone: cDNA cloning, gene organization, expression and biological assay of recombinant proteins.

The crustacean eyestalk CHH/MIH/GIH neurohormone gene family represents a unique group of neuropeptides identified mainly in crustaceans. In this study, we report the cloning and characterization of the cDNA and the gene encoding the hyperglycemic hormone (MeCHH-B) of the shrimp Metapenaeus ensis. The amino acid sequence of MeCHH-B shows 85% identity to that of MeCHH-A (formerly MeCHH-like neuropeptide). Two separate but identical MeCHH-B genes were identified in the genome of shrimp by library screening and they are located on different CHH gene clusters. The organization of the MeCHH-B gene is identical to other members of the CHH/MIH/GIH neurohormone family. MeCHH-B is expressed at a constant level in the eyestalks of juveniles and mature females. Unlike the MeCHH-A gene, a low level of MeCHH-B transcripts can also be detected in the central nervous system. Interestingly, the expression pattern of MeCHH-B in the eyestalk of vitellogenic females is reversed to that of the MeCHH-A gene. At the middle stage of gonad maturation, a minimum level of MeCHH-B transcript was recorded and a maximum level of MeCHH-A transcript was detected. Recombinant proteins for MeCHH-A and MeCHH-B were produced by a bacterial expression system. The hemolymph glucose level of bilaterally eyestalk-ablated shrimp increased two-fold 1 h after the rCHH injection and then returned to normal after 2 h. The hyperglycemic effect of these fusion proteins is comparable to that of de-stalked shrimp injected with crude extract from a single sinus gland.

Amino Acid Sequence↗

PubMed2000

Inhibitors of tripeptidyl peptidase II. 2. Generation of the first novel lead inhibitor of cholecystokinin-8-inactivating peptidase: a strategy for the design of peptidase inhibitors.

The cholecystokinin-8 (CCK-8)-inactivating peptidase is a serine peptidase which has been shown to be a membrane-bound isoform of tripeptidyl peptidase II (EC 3.4.14.10). It cleaves the neurotransmitter CCK-8 sulfate at the Met-Gly bond to give Asp-Tyr(SO(3)H)-Met-OH + Gly-Trp-Met-Asp-Phe-NH(2). In seeking a reversible inhibitor of this peptidase, the enzymatic binding subsites were characterized using a fluorimetric assay based on the hydrolysis of the artificial substrate Ala-Ala-Phe-amidomethylcoumarin. A series of di- and tripeptides having various alkyl or aryl side chains was studied to determine the accessible volume for binding and to probe the potential for hydrophobic interactions. From this initial study the tripeptides Ile-Pro-Ile-OH (K(i) = 1 microM) and Ala-Pro-Ala-OH (K(i) = 3 microM) and dipeptide amide Val-Nvl-NHBu (K(i) = 3 microM) emerged as leads. Comparison of these structures led to the synthesis of Val-Pro-NHBu (K(i) = 0.57 microM) which served for later optimization in the design of butabindide, a potent reversible competitive and selective inhibitor of the CCK-8-inactivating peptidase. The strategy for this work is explicitly described since it illustrates a possible general approach for peptidase inhibitor design.

Aminopeptidases↗

PubMed2000

Iris lymphoma in a pediatric cardiac transplant recipient: clinicopathologic findings.

PURPOSE: To report the unusual presentation of a confirmed iris lymphoma in the setting of posttransplant lymphoproliferative disorder. DESIGN: Case report with clinicopathologic findings. METHODS: The medical record was reviewed for clinical manifestations, course of disease, and pathologic and radiologic findings. RESULTS: A 4-year-old girl who had undergone a cardiac transplant at 3 months of age was found to have unilateral iris lesions associated with granulomatous uveitis. Her condition was unresponsive to local and systemic steroids, so she underwent an iris biopsy that was found to contain a B cell-derived monoclonal lymphoproliferation. Treatment with systemic chemotherapy including cyclophosphamide and prednisone resulted in a transient, partial response. Localized radiotherapy induced total regression of the iris lesions. She continues to be observed and has been free of recurrence or metastasis for the past 12 months. CONCLUSIONS: Because of the increased use of organ transplantation, eye care specialists should consider the diagnosis of intraocular lymphoma when confronted with uveitis-like syndrome unresponsive to topical steroid therapy. Although there are numerous treatment options for intraocular lymphoma, radiation therapy was found to be effective in the treatment of this case.

Antineoplastic Combined Chemotherapy Protocols↗

PubMed2000

Special postpartum dietary practices of Hong Kong Chinese women.

OBJECTIVE: A 'ginger vinegar soup' and other special dietary practices have been traditionally recommended for postpartum Chinese women. This paper describes these practices in the first 6 weeks postpartum, and details of the calcium and iron content of the 'ginger vinegar soup'. DESIGN AND SUBJECTS: Results of this paper were generated from a longitudinal study on the nutritional status of Hong Kong Chinese postpartum women. 'Ginger vinegar soup' samples were collected at the 2 week home visits. Calcium and iron content were measured by the combination of dry ashing method and atomic absorption spectrophotometry. Results were compared with other types of soup and food sources. A food frequency questionnaire was completed at the 6 week interview to assess the special dietary practices during this period. RESULTS: Fifty-one subjects completed the food frequency questionnaires. Twenty-two ginger vinegar soup samples and six other soup samples were collected. Consumption of special food items such as ginger, pig's trotters, egg and chicken varied greatly among subjects. More poultry and similar amounts of egg were consumed by our subjects as compared with the Hong Kong general population. Chicken soup and ginger vinegar soup were commonly consumed. Median calcium and iron contents of the ginger vinegar soup were 4.65 and 0.84 mg/dl, respectively. This calcium content was higher than that of the other six soup samples, but was low as compared with other calcium-rich foods. Iron content of ginger vinegar soup was higher than that of the other six samples and was comparable to some iron-rich foods. CONCLUSIONS: Hong Kong Chinese postpartum women followed traditional dietary practices to different degrees. These practices were characterized by an increased poultry consumption. Iron content of ginger vinegar soup was comparable to some iron-rich foods.

Adult↗

PubMed2000

Growth and nutrition of Hong Kong children aged 0-7 years.

OBJECTIVE: To study the early dietary practices in relation to growth of Hong Kong children from birth to 7 years. METHODOLOGY: One hundred and seventy-three full-term Hong Kong Chinese babies were recruited at birth and were followed up for anthropometric measurements using standardized methods and dietary assessment using a combination of dietary history, 24 h recall and food frequency. At 7 years, 125 children remained in the study. RESULTS: Mean (SD) birthweight was 3.3 (0.38) kg for boys and 3.1 (0.38) kg for girls. Mean (SD) weight at 7 years was 22.4 (4.2) kg for boys and 21.1 (3.7) kg for girls, and mean (SD) height was 120.3 (4.8) cm for boys and 119.8 (5.1) cm for girls. Hong Kong children were lighter and shorter than Australian children and the National Centre for Health Statistics (NCHS) references, but the magnitude is less than one standard deviation score. Mean weight and height of Hong Kong children were lower compared to Caucasian and Beijing children, with more obvious differences between 1 and 5 years. At 1 year, mean (SD) daily energy intake was 98 (24) kcal/kg/day for boys and 100 (26) kcal/kg/day for girls. By 7 years, it decreased to 82 (18) kcal/kg/day for boys and 73 (22) kcal/kg/day for girls. Between 2 to 4 years of age the energy intake of studied children were slightly lower than the Australian and Finnish children, but the protein intake was higher. Percentage of fat contributing to total daily energy intake was lower throughout at a level of 30%. Such differences in diet reflect a lower consumption of milk fat, higher consumption of meat and lower level of physical activity in Hong Kong children. Intakes of calcium, iron and vitamin C all reached 60% or above of US recommended daily allowance. CONCLUSIONS: The smaller body build of Chinese compared to Caucasians cannot be explained by dietary differences. The diet of Hong Kong children is changing to one which is more Westernized with a higher consumption of animal products.

Anthropometry↗

PubMed2000

Breastfeeding failure in a longitudinal post-partum maternal nutrition study in Hong Kong.

OBJECTIVE: To describe factors associated with breastfeeding failure during the first 6 months post-partum in a sample of Hong Kong Chinese women participating in a longitudinal study of maternal nutrition. METHODOLOGY: Forty-four Hong Kong Chinese lactating mothers who intended to breastfeed exclusively for at least 3 months were recruited and followed for 6 months post-partum. Demographic data were compared with 20 mothers who intended to use formula feeding. Mothers were followed up at 2 and 6 weeks and 3 and 6 months and details of infant feeding practices were obtained. Information was sought on breastfeeding management in hospital, reasons for discontinuation of breastfeeding or for providing supplements to babies and intention to seek, and sources of, lactation support. RESULTS: Thirty-nine mothers who planned to breastfeed completed the follow up. Compared with mothers in the formula-feeding group, breastfeeding mothers were more likely to be professionals or housewives. Continuation of any breastfeeding (total and partial) was noted in 30 (77%), 22 (57%), 16 (41%) and 12 (31%) mothers at 2 and 6 weeks and 3 and 6 months post-partum, respectively. The majority (97%) of mothers stated that they were given information on the benefits and management of breastfeeding. However, late initiation of breastfeeding and providing supplements to babies were common. Perceptions of insufficient milk supply (44%), breast problems (31%) and being too tired (28%) were the main reasons stated for stopping breastfeeding or for providing supplements to babies. Midwives from the postnatal wards and hotlines were the main sources of lactation support. CONCLUSIONS: These results highlight difficulties in sustaining breastfeeding, either exclusive or partial, in Hong Kong Chinese women. Despite being recruited on the basis of intending to exclusively breastfeed for 3 months, less than half these mothers were still breastfeeding and only approximately one-third were exclusively or predominantly breastfeeding at 3 months. More needs to be done within the hospital environment to initiate breastfeeding immediately after birth and to avoid giving unnecessary supplements and more effort is needed to foster a mother's confidence, commitment and knowledge of breastfeeding.

Adult↗