The binding of beta-casein to hydroxyapatite: the effect of phosphate content and location.

The elution behaviour of beta-casein from columns of hydroxyapatite has been studied and the effect examined of the enzymic addition of an extra phosphate residue. When the additional phosphate is located near pre-existing phosphate residues stronger binding to hydroxyapatite is observed. When the additional phosphate is remote from the pre-existing phosphates no increase in strength of binding is observed. It is suggested that the clustering of phosphate residues which characterizes alphas- and beta-caseins can be rationalized on the basis that it facilitates co-operative interactions between these phosphates and the Ca phosphate of the casein micelle and/or basic residues within casein polypeptide chains.     

Amount of prenatal visual stimulation alters incubation time and postnatal preferences in leopard geckos (Eublepharis macularius).

The authors exposed gecko (Eublepharis macularius) embryos to patterned visual stimulation beginning at either 1 week or 2 weeks prior to hatching. Embryos exposed to the substantially augmented amount of prenatal visual stimulation hatched significantly earlier than the embryos either exposed to the moderately augmented prenatal visual stimulation or not exposed to any prenatal visual stimulation (p?p?p?     

Augmented prenatal auditory stimulation alters postnatal perception, arousal, and survival in bobwhite quail chicks

Progress in biological psychiatry is contingent on progress in neurobiology and on research into proper characterisation and assessment of abnormal behavior. Advances in neurobiology are rapid and steady; diagnostic research does not keep pace. On the contrary, the diagnostic approach seems solidified, as today's basic premises are uncritically accepted. The diagnostic requirements for meaningful biological psychiatric research are discussed and contrasted with present-day diagnostic practices. Serious reflection on the state of psychiatric diagnosing is urgently needed.     

A model of the electrocortical effects of general anaesthesia

INTRODUCTION: Iodine containing agents are used as radiologic contrast media and for the treatment of upper respiratory infections, heart diseases, thyreotoxicosis, erythema nodosum and wound disinfection. Vegetating iododerma is a rare but severe cutaneous side effect. CASE STUDY: We report a case of iododerma in a 84 year-old patient, presenting iododerma 14 months after introduction of amiodarone treatment. Despite cessation of this therapy, an important exacerbation of the skin lesions was observed 3 months later. Therapy with cyclosporine produced a marked regression of the skin lesions. DISCUSSION: We are aware of only one other reported case of amiodarone induced iododerma, which occurred after 2 years of therapy. Our patient was also exposed to iodine containing radiographic contrast media 1 and 18 years before onset of the actual skin disease. A sensitizing role of these injections is possible, but we feel that they did not directly induce the skin eruption as all reported cases occurred within a few days after exposure. CONCLUSION: Amiodarone can exceptionally be responsible for severe iododerma. Cyclosporine is, according to our experience, a valuable therapeutic option.     

CFD simulation of airborne pathogen transport due to human activities

Computational Fluid Dynamics (CFD) is an increasingly popular tool for studying the impact of design interventions on the transport of infectious microorganisms. While much of the focus is on respiratory infections, there is substantial evidence that certain pathogens, such as those which colonise the skin, can be released into, and transported through the air through routine activities. In these situations the bacteria is released over a volume of space, with different intensities and locations varying in time rather than being released at a single point.     

Heart rate variability and preoperative anxiety

Power spectral analysis of heart rate variability has been used to gain some understanding of the activity of the autonomic nervous system. In this study various indices of heart rate variability were related to the degree of preoperative anxiety experienced by 32 patients presenting for day case surgery. It was found that there was no correlation between anxiety and mean heart rate, or between anxiety and the spectral power in the mid frequency band (0.05-0.15 Hz). However, there was an increase in the relative power of the higher frequency band (0.15-0.5 Hz) with increasing anxiety levels (Spearman correlation r = 0.4034). This suggests that preoperative anxiety may often be associated with a relative vagal predominance in the sympathovagal balance.     

Intersensory experience and early perceptual development: Postnatal experience with multimodal maternal cues affects intersensory responsiveness in Bobwhite Quail Chicks.

Unlike the other sensory modalities of precocial infants, the visual modality does not normally become functional until after birth or hatching. Despite this unique developmental status, the role of emerging visual experience on postnatal perceptual organization remains unclear. In this study, bobwhite quail hatchlings were reared in conditions that manipulated postnatal experience with maternal visual cues, either alone or in conjunction with maternal auditory cues. Results revealed that bobwhite chicks require postnatal exposure to both maternal auditory and visual cues following hatching to demonstrate species-specific perceptual preferences. Chicks that received temporally disparate maternal auditory and visual cues or experience with only maternal visual or maternal auditory cues failed to show species-typical perceptual responsiveness. These results suggest that developmental mechanisms involving both visual and auditory sensory experience underlie the emergence of early intersensory integration. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Formation of complexes between lecithin and apovitellenin I,an avian egg-yolk apoprotein

In a study of lipid-protein interactions in egg yolk, it was found that L-α-dipalmitoyl lecithin gave two distinct noncovalent complexes (A and B) with apovitellenin I, an apoprotein in the major yolk lipoprotein. Interaction took place under widely varied conditions, and yolk lecithin gave similar complexes. Complex A, which was formed within minutes, consisted of round particles of about 9 nm diameter. Complex B, which was formed more slowly, consisted of larger, particles. Possibly resembling curved discs, with diameter of 30–40 nm. The preparation and some properties of these complexes are described. It is suggested that they may be suitable for an extensive study of phospholipid-protein interactions in yolk.     

Persistent diarrhoea in children admitted to Port Moresby General Hospital

A retrospective study of the records of children admitted to Port Moresby General Hospital with diarrhoea during 1992 and 1993 was carried out to determine the morbidity, mortality and risk factors associated with persistent diarrhoea. 858 admissions of children under five years of age who had diarrhoea were identified from the ward admission registers, and case records for 724 were studied. Persistent diarrhoea occurred in 20%, and nearly half of these were in the 12-23 months age group. Children with persistent diarrhoea had a case fatality rate of 4.9%. Seasonality was similar for both persistent and non-persistent diarrhoea. In the crude analysis children of 12 months and older had a greater risk of developing persistent diarrhoea than those less than 12 months (odds ratio for children 12-23 months was 2.0 and for children 24-59 months 1.7; confidence intervals were 1.2-3.1 and 1.0-2.9 respectively); however, this difference was not found after logistic regression analysis. Poor nutritional status was a significant risk factor for persistent diarrhoea and remained so after controlling for confounding variables (odds ratio 2.7; confidence interval 1.8-4.0).