Louise Bennett

Cow's Milk Allergy: A Complex Disorder

Cow’s milk allergy (CMA) is a complex disorder. Numerous milk proteins have been implicated in allergic responses and most of these have been shown to contain multiple allergenic epitopes. There is considerable heterogeneity amongst allergic individuals for the particular proteins and epitopes to which they react, and to further complicate matters, allergic reactions to cow’s milk are driven by more than one immunological mechanism. Finally, the incidence and dominant allergic mechanisms change with age, with IgE-mediated reactions common in infancy and non-IgE-mediated reactions dominating in adults. The complexity of CMA has lead to many public misconceptions about this disorder, including confusion with lactose intolerance and frequent self-misdiagnosis. Indeed, the prevalence of self-diagnosed CMA in the community is 10-fold higher than the clinically proven incidence, suggesting a sizable population is unnecessarily eschewing dairy products. Avoidance of dairy foods, whether for true or perceived CMA, carries with it nutritional consequences and the provision of appropriate nutritional advice is important. In this review, the epidemiology and natural course of CMA is discussed along with our current understanding of its triggers and immunological mechanisms. We examine current strategies for the primary and secondary prevention of allergic sensitization and the ongoing search for effective therapies to ultimately cure CMA.

The evaluation of colour in natural waters

Abstract A model describing the objective evaluation of colour from the transmission properties of natural waters was developed and applied to a wide range of Australian waters. These calculated colours show that measurement of filtered water absorbance at 456 nm calibrated against Pt-Co colour standards agrees with the visually perceived colour intensity by comparator methods and the Pt-Co or Hazen scale of measurement within a maximum error range of ±20%. The error is significantly larger when analytical wavelengths below 440 nm are used. The interference to colour measurement caused by scattering of suspended matter was accounted for at the analytical wavelength. The light scatter component was found to be significant when the ratio of turbidity (in nephelometric turbidity units) to colour (in Hazen units) is greater than 0.02. The use of the 456 nm wavelength is proposed for the standardization of colour measurement in natural waters.

Evaluating the traditional Chinese literature for herbal formulae and individual herbs used for age-related dementia and memory impairment.

Natural products are the basis of many systems of traditional medicine and continue to provide sources for new drugs. Ethnobiological approaches to drug discovery that have proven productive in the past include the investigation of traditional medical literatures. This study describes a broadly applicable method for locating, selecting and evaluating citations in the traditional Chinese herbal medicine literature of the dynastic period (until 1911) for specific symptoms or disorders. This methodology is applied to evaluate multi-herb formulae for age-related dementia and memory impairment. Of the 174 multi-herb formulae located in the searches, 19 were for disorders broadly consistent with amnestic Mild Cognitive Impairment (MCI) and/or Age Associated Memory Impairment (AAMI). These appeared in books written between c. 650 to 1911. Of the 176 herbs that appeared in these 19 formulae, those with the highest frequencies were tabulated and hierarchical cluster analysis was undertaken. Chinese pharmacopoeias were consulted to determine the botanical identity of the herbs and also which herbs within the formulas were specific for memory disorders. This study found that the top ten herbs, in terms of frequency of inclusion in multi-herb formulae specific for age-related memory disorders, were all listed in the pharmacopoeias for memory disorders and these formed three clusters. The herbs identified in this study may warrant further experimental and clinical evaluation both individually and in combination.

Singlet oxygen formation in monomeric and aggregated porphyrin c.

The absorption and fluorescence spectra of monomeric and aggregated species present in aqueous solutions of porphyrin c have been resolved by steady-state and time-resolved spectroscopy. The dependence of the singlet oxygen formation yield (phi delta) on excitation wavelength has also been determined. In the Q-band spectral region, the aggregate absorption and emission spectra are shifted to longer wavelengths with respect to the monomer spectrum with phi delta (monomer) = 0.59 and phi delta (aggregate) = 0.33. The relevance of these findings to the optimization of irradiation conditions in tumour phototherapy using porphyrin c are discussed.

Inhibition of angiotensin converting enzyme (ACE) activity by polyphenols from tea (Camellia sinensis) and links to processing method

The focus of this study was to investigate Angiotensin Converting Enzyme (ACE) inhibiting activity across 34 teas (Camellia sinensis) produced by 5 different processing methods including green (GT), oolong (OT), white (WT), black (BT) and dark (DT) teas. In vitro ACE inhibitory activity was affected by the tea processing method with IC(50) values for ACE inhibition: green < oolong < white < black < dark teas. Substrate-dependence of the reaction kinetics was studied for GT and BT polyphenolic size fractions either < or > 3 kDa and also Green Tea Polyphenolic Isolate (GTPI), and revealed that enzyme velocity curves fitted allosteric, not Michaelis-Menten, relationships. Inhibition was weakly dependent on substrate concentration for GT fraction >3 kDa and independent of substrate concentration for all other GT and BT size fractions and GTPI. Furthermore, evidence for direct inactivation of ACE by GTPI was demonstrated. Overall, the results suggest that tea polyphenolics exert a mixed mode of in vitro inhibition of ACE, mostly of a kinetically uncompetitive type. The results are discussed in the context of in vivo and epidemiological evidence for regulation of blood pressure by tea consumption.

Vitamin D2-Enriched Button Mushroom (Agaricus bisporus) Improves Memory in Both Wild Type and APPswe/PS1dE9 Transgenic Mice

Vitamin D deficiency is widespread, affecting over 30% of adult Australians, and increasing up to 80% for at-risk groups including the elderly (age>65). The role for Vitamin D in development of the central nervous system is supported by the association between Vitamin D deficiency and incidence of neurological and psychiatric disorders including Alzheimer’s disease (AD). A reported positive relationship between Vitamin D status and cognitive performance suggests that restoring Vitamin D status might provide a cognitive benefit to those with Vitamin D deficiency. Mushrooms are a rich source of ergosterol, which can be converted to Vitamin D2 by treatment with UV light, presenting a new and convenient dietary source of Vitamin D2. We hypothesised that Vitamin D2-enriched mushrooms (VDM) could prevent the cognitive and pathological abnormalities associated with dementia. Two month old wild type (B6C3) and AD transgenic (APPSwe/PS1dE9) mice were fed a diet either deficient in Vitamin D2 or a diet which was supplemented with VDM, containing 1±0.2 µg/kg (∼54 IU/kg) vitamin D2, for 7 months. Effects of the dietary intervention on memory were assessed pre- and post-feeding. Brain sections were evaluated for amyloid β (Aβ) plaque loads and inflammation biomarkers using immuno-histochemical methods. Plasma vitamin D metabolites, Aβ40, Aβ42, calcium, protein and cholesterol were measured using biochemical assays. Compared with mice on the control diet, VDM-fed wild type and AD transgenic mice displayed improved learning and memory, had significantly reduced amyloid plaque load and glial fibrillary acidic protein, and elevated interleukin-10 in the brain. The results suggest that VDM might provide a dietary source of Vitamin D2 and other bioactives for preventing memory-impairment in dementia. This study supports the need for a randomised clinical trial to determine whether or not VDM consumption can benefit cognitive performance in the wider population.

Anti-inflammatory effects of five commercially available mushroom species determined in lipopolysaccharide and interferon-γ activated murine macrophages

Inflammation is a well-known contributing factor to many age-related chronic diseases. One of the possible strategies to suppress inflammation is the employment of functional foods with anti-inflammatory properties. Edible mushrooms are attracting more and more attention as functional foods since they are rich in bioactive compounds, but their anti-inflammatory properties and the effect of food processing steps on this activity has not been systematically investigated. In the present study, White Button and Honey Brown (both Agaricus bisporus), Shiitake (Lentinus edodes), Enoki (Flammulina velutipes) and Oyster mushroom (Pleurotus ostreatus) preparations were tested for their anti-inflammatory activity in lipopolysaccharide (LPS) and interferon-γ (IFN-γ) activated murine RAW 264.7 macrophages. Potent anti-inflammatory activity (IC₅₀<0.1 mg/ml), measured as inhibition of NO production, could be detected in all raw mushroom preparations, but only raw Oyster (IC₅₀=0.035 mg/ml), Shiitake (IC₅₀=0.047 mg/ml) and Enoki mushrooms (IC₅₀=0.099 mg/ml) showed also potent inhibition of TNF-α production. When the anti-inflammatory activity was followed through two food-processing steps, which involved ultrasonication and heating, a significant portion of the anti-inflammatory activity was lost suggesting that the anti-inflammatory compounds might be susceptible to heating or prone to evaporation.

THE ‘Q-BAND’ ABSORPTION spECTRA OF HEMATOPORPHYRIN MONOMER AND AGGREGATE IN AQUEOUS SOLUTION

Abstract The resolution of the absorption spectra in the Q band (480 nm‐620 nm) spectral region of monomeric and dimeric hematoporphyrin species present in aqueous solutions has been achieved using absorption, fluorescence and computer analysis methods. The absorption maxima of the dimer in this spectral region are red shifted about 12 nm with respect to those of the monomer. The significance of this finding in relationship to the well documented blue shift of hematoporphyrin aggregate observed in the Soret band region (λmalx∼400 nm) of the absorption spectrum is discussed.

Anti-inflammatory activity of cinnamon (C. zeylanicum and C. cassia) extracts – identification of e-cinnamaldehyde and o-methoxy cinnamaldehyde as the most potent bioactive compounds

Chronic inflammation is a contributing factor in many age-related diseases. In a previous study, we have shown that Sri Lankan cinnamon (C. zeylanicum) was one of the most potent anti-inflammatory foods out of 115 foods tested. However, knowledge about the exact nature of the anti-inflammatory compounds and their distribution in the two major cinnamon species used for human consumption is limited. The aim of this investigation was to determine the anti-inflammatory activity of C. zeylanicum and C. cassia and elucidate their main phytochemical compounds. When extracts were tested in LPS and IFN-γ activated RAW 264.7 macrophages, most of the anti-inflammatory activity, measured by down-regulation of nitric oxide and TNF-α production, was observed in the organic extracts. The most abundant compounds in these extracts were E-cinnamaldehyde and o-methoxycinnamaldehyde. The highest concentration of E-cinnamaldehyde was found in the DCM extract of C. zeylanicum or C. cassia (31 and 34 mg g(-1) of cinnamon, respectively). When these and other constituents were tested for their anti-inflammatory activity in RAW 264.7 and J774A.1 macrophages, the most potent compounds were E-cinnamaldehyde and o-methoxycinnamaldehyde, which exhibited IC₅₀ values for NO with RAW 264.7 cells of 55 ± 9 μM (7.3 ± 1.2 μg mL(-1)) and 35 ± 9 μM (5.7 ± 1.5 μg mL(-1)), respectively; and IC₅₀ values for TNF-α of 63 ± 9 μM (8.3 ± 1.2 μg mL(-1)) and 78 ± 16 μM (12.6 ± 2.6 μg mL(-1)), respectively. If therapeutic concentrations can be achieved in target tissues, cinnamon and its components may be useful in the treatment of age-related inflammatory conditions.

Chinese herbal medicine for Mild Cognitive Impairment and Age Associated Memory Impairment: a review of randomised controlled trials

This review assesses the effectiveness and safety of Chinese herbal medicines (CHM) for Mild Cognitive Impairment (MCI) and Age Associated Memory Impairment (AAMI). Electronic searches of English and Chinese databases and hand searches of Chinese journal holdings were conducted. Randomised controlled trials comparing orally administered CHM with placebo, no intervention or other therapy were considered. Ginkgo biloba was excluded. Ten trials met inclusion criteria. Eight different CHM were investigated. Methodological quality was assessed using the Jadad scale and five studies scored three or above. Two studies compared CHM with placebo and eight with another intervention. This review found an overall benefit on some outcome measures for the eight CHMs involved in the 10 RCTs but methodological and data reporting issues were evident. Meta-analysis of three studies found the effects of the CHMs were at least equivalent to piracetam on Mini-Mental State Examination (MMSE) scores. No severe adverse events were reported.