Reducing the glycemic impact of carbohydrates on foods and meals: Strategies for the food industry and consumers with special focus on Asia.

Type 2 diabetes is increasingly prevalent in Asia, which can be attributed to a carbohydrate-rich diet, consisting of foods in the form of grains, for example, rice, or a food product made from flours or isolated starch, for example, noodles. Carbohydrates become a health issue when they are digested and absorbed rapidly (high glycemic index), and more so when they are consumed in large quantities (high glycemic load). The principal strategies of glycemic control should thus aim to reduce the amount of carbohydrate available for digestion, reduce the rate of digestion of the food, reduce the rate of glucose absorption, and increase the rate of glucose removal from blood. From a food perspective, the composition and structure of the food can be modified to reduce the amount of carbohydrates or alter starch digestibility and glucose absorption rates via using different food ingredients and processing methods. From a human perspective, eating behavior and food choices surrounding a meal can also affect glycemic response. This review therefore identifies actionable strategies and opportunities across foods and meals that can be considered by food manufacturers or consumers. They are (a) using alternative ingredients, (b) adding functional ingredients, and (c) changing processing methods and parameters for foods, and optimizing (a) eating behavior, (b) preloading or co-ingestion of other macronutrients, and (c) meal sequence and history. The effectiveness of a strategy would depend on consumer acceptance, compatibility of the strategy with an existing food product, and whether it is economically or technologically feasible. A combination of two or more strategies is recommended for greater effectiveness and flexibility.

Molecular, rheological and physicochemical characterisation of puka gum, an arabinogalactan-protein extracted from the Meryta sinclairii tree.

A water-soluble polysaccharide (type II arabinogalactan-protein) extracted from the gum exudate of the native New Zealand puka tree (Meryta sinclairii), was characterised for its molecular, rheological and physicochemical properties. In 0.1 M NaCl, the weight average molecular weight (Mw) of puka gum is 5.9 × 106 Da with an RMS radius of 56 nm and z-average hydrodynamic radius of 79 nm. The intrinsic viscosity of the polysaccharide is 57 ml/g with a coil overlap concentration 15% w/w. Together, the shape factor, p, of 0.70 (exponent of RMS radius vs. hydrodynamic radius), Smidsrød-Haug's stiffness parameter B of 0.031 and Mark-Houwink exponent α of 0.375 indicate that the polysaccharide adopts a spherical conformation in solution, similar to gum arabic. The pKa is 1.8. The polysaccharide exhibits a Newtonian to shear-thinning behaviour from 0.2 to 25% w/w. Viscosity of the polysaccharide (1 s-1) decreases with decreasing concentration, increasing temperature, ionic strength, and at acidic pH.

Yin Yang 1-mediated epigenetic silencing of tumour-suppressive microRNAs activates nuclear factor-κB in hepatocellular carcinoma.

Enhancer of zeste homolog 2 (EZH2) catalyses histone H3 lysine 27 trimethylation (H3K27me3) to silence tumour-suppressor genes in hepatocellular carcinoma (HCC) but the process of locus-specific recruitment remains elusive. Here we investigated the transcription factors involved and the molecular consequences in HCC development. The genome-wide distribution of H3K27me3 was determined by chromatin immunoprecipitation coupled with high-throughput sequencing or promoter array analyses in HCC cells from hepatitis B virus (HBV) X protein transgenic mouse and human cell models. Transcription factor binding site analysis was performed to identify EZH2-interacting transcription factors followed by functional characterization. Our cross-species integrative analysis revealed a crucial link between Yin Yang 1 (YY1) and EZH2-mediated H3K27me3 in HCC. Gene expression analysis of human HBV-associated HCC specimens demonstrated concordant overexpression of YY1 and EZH2, which correlated with poor survival of patients in advanced stages. The YY1 binding motif was significantly enriched in both in vivo and in vitro H3K27me3-occupied genes, including genes for 15 tumour-suppressive microRNAs. Knockdown of YY1 reduced not only global H3K27me3 levels, but also EZH2 and H3K27me3 promoter occupancy and DNA methylation, leading to the transcriptional up-regulation of microRNA-9 isoforms in HCC cells. Concurrent EZH2 knockdown and 5-aza-2'-deoxycytidine treatment synergistically increased the levels of microRNA-9, which reduced the expression and transcriptional activity of nuclear factor-κB (NF-κB). Functionally, YY1 promoted HCC tumourigenicity and inhibited apoptosis of HCC cells, at least partially through NF-κB activation. In conclusion, YY1 overexpression contributes to EZH2 recruitment for H3K27me3-mediated silencing of tumour-suppressive microRNAs, thereby activating NF-κB signalling in hepatocarcinogenesis.

The cation-controlled and hydrogen bond-mediated shear-thickening behaviour of a tree-fern isolated polysaccharide.

The shear-thickening rheological behaviour (between 5 and 20s(-1)) of a 5% (w/w) viscoelastic gum extracted from the fronds of the native New Zealand black tree fern or mamaku in Maori was further explored by manipulating the salt content. The freeze-dried mamaku gum contained a high mineral content and sugars which upon removal via dialysis, resulted in the loss of shear thickening. However, this loss was reversible by the addition of salts to the dialysed dispersion. The mechanism of shear-thickening behaviour was therefore hypothesised to be due to shear-induced transition of intra- to intermolecular hydrogen bonding, promoted by the screening effect of cations. Mono-, di- and trivalent salts, i.e. Na(+), K(+), N(CH3)4(+), Ca(2+), Mg(2+), Al(3+) and La(3+) at concentrations between 0.001 and 1.0M were tested to support the hypothesis as well as to demonstrate the sensitivity of the biopolymer to cation valency and concentrations. The cation valency and concentration were crucial factors in determining: (i) zero-shear viscosity, (ii) critical shear rate, γ˙c (or shear rate at the onset of shear-thickening) and (iii) the extent of shear-thickening of the solution. For mono- and divalent cations these parameters were similar at equivalent ionic strengths and fairly independent of the cation type. Trivalent cations (La(3+)) however caused precipitation of the gum in the concentration range of 0.005-0.05 M but clear dispersions were obtained above 0.05 M.

Epigenetic silencing of miR-490-3p reactivates the chromatin remodeler SMARCD1 to promote Helicobacter pylori-induced gastric carcinogenesis.

Chromatin remodeling has emerged as a hallmark of gastric cancer, but the regulation of chromatin regulators other than genetic change is unknown. Helicobacter pylori causes epigenetic dysregulation to promote gastric carcinogenesis, but the roles and functions of microRNAs (miRNA) in this multistage cascade are not fully explored. In this study, miRNA expression in preneoplastic and neoplastic lesions in murine stomachs induced by H. pylori and N-methyl-N-nitrosourea (MNU) was profiled by miRNA expression array. miR-490-3p exhibited progressive downregulation in gastritis, intestinal metaplasia, and adenocarcinoma during H. pylori and MNU-induced gastric carcinogenesis. Significant downregulation of miR-490-3p was confirmed in human gastric cancer tissues in which its regulatory region was found to be hypermethylated. miR-490-3p exerted growth- and metastasis-suppressive effects on gastric cancer cells through directly targeting SMARCD1, a SWItch/Sucrose NonFermentable (SWI/SNF) chromatin remodeling complex subunit. Knockdown of SMARCD1 significantly attenuated the protumorigenic effects of miR-490-3p inhibitor, whereas enforced expression of SMARCD1 promoted in vitro and in vivo oncogenic phenotypes of gastric cancer cells. SMARCD1 was markedly upregulated in gastric cancer in which its high expression was associated with shortened patients' survival independent of TNM staging. In conclusion, hypermethylation-mediated silencing of miR-490-3p reactivates SMARCD1 to confer malignant phenotypes, mechanistically linking H. pylori, chromatin remodeling, and gastric carcinogenesis.

Structure of a shear-thickening polysaccharide extracted from the New Zealand black tree fern, Cyathea medullaris.

A shear-thickening water-soluble polysaccharide was purified from mucilage extracted from the fronds of the New Zealand black tree fern (Cyathea medullaris or 'mamaku' in Maori) and its structure characterised. Constituent sugar analysis by three complementary methods, combined with linkage analysis (of carboxyl reduced samples) and 1H and 13C nuclear magnetic resonance spectroscopy (NMR) revealed a glucuronomannan comprising a backbone of 4-linked methylesterified glucopyranosyl uronic acid and 2-linked mannopyranosyl residues, branched at O-3 of 45% and at both O-3 and O-4 of 53% of the mannopyranosyl residues with side chains likely comprising terminal xylopyranosyl, terminal galactopyranosyl, non-methylesterified terminal glucopyranosyl uronic acid and 3-linked glucopyranosyl uronic acid residues. The weight-average molecular weight of the purified polysaccharide was ∼1.9×10(6) Da as determined by size-exclusion chromatography coupled with multi-angle laser light scattering (SEC-MALLS). The distinctive rheological properties of this polysaccharide are discussed in relation to its structure.

Mining the adenovirus virome for oncolytics against multiple solid tumor types.

Although there are 55 serotypes of adenovirus (Ad) that infect humans, Ad serotype 5 (Ad5) is the most widely studied because of the availability of commercial kits for its genetic manipulation. In fact, engineered Ad 5 is currently being used in all of the 87 global clinical trials utilizing Ad for the treatment of cancer. Unfortunately, Ad5 is one of the most seroprevalent serotypes, meaning that this virus has to confront additional immunological barriers to be effective in Ad5-immune patients. In this work, we compare Ad5 to 13 other adenoviral serotypes from species B, C, D and E for oncolytic potential in both immunodeficient mouse and immunocompetent hamster models. Our results indicate that species D Ads are not effective oncolytics against most solid tumors. Conversely, lower seroprevalent Ad6 and Ad11 had anti-cancer activity comparable to Ad5. This work strongly supports the consideration of Ad6-based oncolytic therapies for the treatment of breast, ovarian, kidney and liver tumors.

Development of an instrument measuring Chinese adolescent beliefs and attitudes towards substance abuse.

AIM: To develop an instrument measuring the beliefs and attitudes of Chinese adolescents towards substance abuse. BACKGROUND: It is documented that many negative consequences for youth, including physical, mental and psychosocial health problems are associated with substance abuse. There has led to a growing concern about promoting anti-drug education among health care professionals in Hong Kong. It is therefore important to conduct research on substance abuse to promote more effective anti-drug programmes for adolescents. To conduct research on the above aspect, valid and reliable instruments for measuring factors associated with drug abuse are needed. An instrument, namely the Beliefs and Attitudes of Substance Abuse Inventory (BASAI) was developed for the purpose of this study. DESIGN AND METHODS: Both qualitative and quantitative approaches to instrument development were adopted in the study. There were two phases to the study. Relevant literature and the Delphi technique were employed in the first phase of the study. A panel of experts was interviewed for the development of a pool of items for the instrument. Content analysis was used to manage the qualitative data obtained from the interviews. Factor analysis was used for the psychometric testing of the items of the BASAI. A Cronbach's alpha coefficient was used to test the internal consistency of the instrument. The standard error of the mean (SEM) was measured to further support the reliability of the BASAI. The results are estimates of the validity and reliability of the instrument. RESULTS: Three main categories and nine sub-categories were derived from the interview data in the first phase of the study. The overall inter-rater reliability of the categories was 0.89 (kappa statistics). In the second phase, a Content Validity Index (CVI) of 0.92 for the instrument was achieved with the assistance of another panel of experts. The factor structure of the instrument was identified by undertaking a Principal Component Analysis. Three factors were extracted with a total variance account of approximately 70%. Reliability was established with alpha = 0.82 for the entire scale and a range of 0.78-0.92 between the sub-scales of the instrument. A small SEM of 3.21% was calculated to further support the reliability. CONCLUSION: A culturally sensitive instrument was developed with a satisfactory level of validity and reliability. Further research is recommended to continuously improve and refine the instrument so that it can be useful currently in research and/or practice. RELEVANCE TO CLINICAL PRACTICE: To promote the healthy development of children and adolescents, child health professionals need to implement effective health promotion strategies including anti-drug programmes. The instrument that was developed in this study will hopefully contribute to the development of more effective and evidence-based anti-drug programmes for youths.

Development of a data collecting tool to explore the consuming patterns of Chinese and Western medicines in Hong Kong.

Chinese and Western medicines are both consumed by citizens in Hong Kong. Safe medication practice, however, whether or not it is conducted by Hong Kong citizens, remains unknown. A data collecting tool was developed to explore the consuming patterns of medicines adopted by Hong Kong citizens. It is hoped that by using this tool, baseline information about the ways in which Hong Kong citizens consume their medicines can be explored. It is also hoped that the information will contribute to the educational planning of community-based safe medication practice. The objectives of this paper were thus to report the development of this data collecting tool and to discuss the use of the tool for the promotion of community-based safe medication practice.

Testing Orem's Self-Care Agency and Basic Conditioning Factors in a Chinese community undergoing haemodialysis.

This paper reports results of tests of Orem's Self-Care Agency and Basic Conditioning Factors in a Chinese community undergoing haemodialysis measured by the modified Chinese version of the ASA scale. Eighty-six patients from one major city of China, Tianjin, all of whom had end stage renal disease and were undergoing haemodialysis formed the sample of the study. The research instrument employed in the study was the modified version of the Appraisal of Self-care Agency Scale, developed for use with patients undergoing haemodialysis. The levels of self-care agency of the patients were identified with respect to the findings of the study. The relationships between the self-care agency and basic conditioning factors were investigated by the use of Spearman Rank Correlation Coefficients and the relationships were statistically supported by the findings of this research.

Development of an instrument to measure the responses and management of Chinese primary caregivers in caring of children with minor upper respiratory disorders.

This article focuses on the development of a valid, reliable and culturally sensitive instrument to assess the responses and management of Chinese primary caregivers caring for children aged below 10 with minor upper respiratory disorders. Thirty-two semi-structured interviews were conducted as the point of saturation of qualitative data was reached. The qualitative findings contributed to the development of the instrument items. Five main categories and 29 sub-categories were identified with satisfactory inter-coder reliability. A panel of three experts judged the content validity of the instrument with a content validity index of 0.98. A test-retest procedure with 40 subjects was adopted and the correlation coefficient for the instrument was 0.850 (p< or =0.000).

Contextualising the appraisal of Self-care Agency Scale in Hong Kong.

Published reports on the use of the Appraisal of Self-care Agency (ASA) Scale among Chinese people are scarce, the procedure of testing the ASA Scale is thus necessary before it is used clinically on Chinese population. The objective of this study was to test the validity and reliability of the ASA Scale on the Chinese population. Qualitative and quantitative approaches were adopted in testing the Scale. A panel of 4 experts was invited to examine the content of the Scale and 128 elderly peoplefrom 3 elderly centers in Hong Kong were employed to examine its construct validity. Item analysis was conducted using Cronbach's Alpha coefficient to examine the reliability of the Scale. Content validity index of 0.88 was achieved resultingfrom the assessment of the 4 experts. Sevenfactors were extracted from the factor analysis representing approximately 70% of variance. The reliability coefficient for the entire Scale was 0.72. It was evident that the ASA Scale was a valid and reliable research instrumer that can be used in the Chinese communities.

What does health literacy mean to children?

This study employed the Delphi technique to define the meaning of health literacy to children and to investigate possible ways lead to them to become health literate. According to the experts' perspectives, the meaning of health literacy to children is "to perform physical and psycho-social activities with appropriate standards; being able to interact with people; cope with necessary changes and demand reasonable autonomy so as to achieve complete physical, mental and social well-being". In order to assist children develop healthy physical, psycho-social well-being so as to demonstrate that they are health literate, parents, teachers and significant others have to support and guide the children by demonstrating good practices regarding health-related behaviors. The study serves as a reference for developing healthy childhood that leads to healthy adulthood and healthy elderly.

Modelling observer agreement--an alternative to kappa.

The measurement of agreement among several observers of the same phenomenon has traditionally been analyzed with a kappa coefficient. Recently, methodology for the modelling of such interobserver agreement has been developed. The details and advantages of this methodology are demonstrated by way of the analysis of three examples. Directions for the fitting of these models using the computer program SPSS-X are included in the Appendix.

Role of the Staphylococcus epidermidis slime layer in experimental tunnel tract infections.

An experimental animal model was used to assess the slime layer of Staphylococcus epidermidis as a pathogenic factor in tunnel tract infections. Mice were inoculated with high-slime-producing or non-slime-producing strains of S. epidermidis, either along the length of a subcutaneous catheter or in the area where a catheter had been placed and immediately removed (controls). Among the catheter-bearing mice, the phenotypically distinct staphylococci produced similar, high frequencies of abscess formation (72% [44 of 61] versus 81% [31 of 38]; P = 0.29). In controls, the non-slime-producing organisms were significantly more pathogenic (87% [40 of 46] versus 57% [25 of 44] abscess formation; P = 0.001). No consistent difference was detected between blood isolates obtained from patients with central venous catheter bacteremia and those from neonates with bacteremia in the absence of a prosthetic medical device. Quantitative culture of removed catheters showed greater adherence by the slime-producing isolates (P = 0.014). In this mouse model, slime production by S. epidermidis did not increase the risk of catheter tunnel tract infection, despite the greater catheter adherence of the slime-producing organisms. These findings suggest that traumatized tissue may be a sufficient condition for the development of S. epidermidis catheter-associated infections.

Longitudinal analysis of categorical epidemiological data: a study of Three Mile Island.

The accident at the Three Mile Island nuclear power plant in 1979 led to an unprecedented set of events with potentially life threatening implications. This paper focusses on the analysis of a longitudinal study of the psychological well-being of the mothers of young children living within 10 miles of the plant. The initial analyses of the data utilize loglinear/logit model techniques from the contingency table literature, and involve the fitting of a sequence of logit models. The inadequancies of these analyses are noted, and a new class of mixture models for logistic response structures is introduced to overcome the noted shortcomings. The paper includes a brief outline of the methodology relevant for the fitting of these models using the method of maximum likelihood, and then the model is applied to the TMI data. The paper concludes with a discussion of some of the substantive implications of the mixture model analysis.