Distinct epitope structures of defensin-like proteins linked to proline-rich regions give rise to differences in their allergenic activity.

BACKGROUND: Art v 1, Amb a 4, and Par h 1 are allergenic defensin-polyproline-linked proteins present in mugwort, ragweed, and feverfew pollen, respectively. We aimed to investigate the physicochemical and immunological features underlying the different allergenic capacities of those allergens. METHODS: Recombinant defensin-polyproline-linked proteins were expressed in E. coli and physicochemically characterized in detail regarding identity, secondary structure, and aggregation status. Allergenic activity was assessed by mediator releases assay, serum IgE reactivity, and IgE inhibition ELISA using sera of patients from Austria, Canada, and Korea. Endolysosomal protein degradation and T-cell cross-reactivity were studied in vitro. RESULTS: Despite variations in the proline-rich region, similar secondary structure elements were observed in the defensin-like domains. Seventy-four percent and 52% of the Austrian and Canadian patients reacted to all three allergens, while Korean patients were almost exclusively sensitized to Art v 1. This was reflected by IgE inhibition assays demonstrating high cross-reactivity for Austrian, medium for Canadian, and low for Korean sera. In a subgroup of patients, IgE reactivity toward structurally altered Amb a 4 and Par h 1 was not changed suggesting involvement of linear epitopes. Immunologically relevant endolysosomal stability of the defensin-like domain was limited to Art v 1 and no T-cell cross-reactivity with Art v 125-36 was observed. CONCLUSIONS: Despite structural similarity, different IgE-binding profiles and proteolytic processing impacted the allergenic capacity of defensin-polyproline-linked molecules. Based on the fact that Amb a 4 demonstrated distinct IgE-binding epitopes, we suggest inclusion in molecule-based allergy diagnosis.

The Declaration of Sydney on human death.

On 5 August 1968, publication of the Harvard Committee's report on the subject of "irreversible coma" established a standard for diagnosing death on neurological grounds. On the same day, the 22nd World Medical Assembly met in Sydney, Australia, and announced the Declaration of Sydney, a pronouncement on death, which is less often quoted because it was overshadowed by the impact of the Harvard Report. To put those events into present-day perspective, the authors reviewed all papers published on this subject and the World Medical Association web page and documents, and corresponded with Dr A G Romualdez, the son of Dr A Z Romualdez. There was vast neurological expertise among some of the Harvard Committee members, leading to a comprehensible and practical clinical description of the brain death syndrome and the way to diagnose it. This landmark account had a global medical and social impact on the issue of human death, which simultaneously lessened reception of the Declaration of Sydney. Nonetheless, the Declaration of Sydney faced the main conceptual and philosophical issues on human death in a bold and forthright manner. This statement differentiated the meaning of death at the cellular and tissue levels from the death of the person. This was a pioneering view on the discussion of human death, published as early as in 1968, that should be recognised by current and future generations.

Recognizing a mother's voice in the persistent vegetative state.

We studied an 8-year-old boy after a near-drowning left him in a vegetative state (VS) for 4 years before the study. Findings fulfilled all clinical criteria for the diagnosis of VS. The purpose of this study was to investigate whether there was significant differential activation of the brain in response to hearing his mother's voice compared with the voices of unknown women. The data were assessed using quantitative electric tomography (QEEGt), a technique that combines anatomical information of the brain by MRI with EEG patterns to estimate the sources of the EEG within the brain. We found significant differences for EEG frequencies from 14-58 Hz, with a peak at 33.2 Hz (gamma band). The 3D reconstruction showed that these statistical differences were localized in the lateral and posterior regions of the left hemisphere. No significant differences were found between unknown women vs. basal conditions. These results demonstrate recognition of the mother's voice and indicate high-level residual linguistic processing in a patient meeting clinical criteria for VS. These findings launch new ethical and practical implications for the management of VS patients.

The role of fibroblast growth factor (FGF) and type beta transforming growth factor (TGF-beta 1-beta 2-beta 3) during rat craniofacial development.

Growth factors seem to be part of a complex cellular signalling language, in which individual growth factors are the equivalents of the letters that compose words. According to this analogy, informational content lies, not in an individual growth factor, but in the entire set of growth factors and others signals to which a cell is exposed. The ways in which growth factors exert their combinatorial effects are becoming clearer as the molecular mechanisms of growth factors actions are being investigated. A number of related extracellular signalling molecules that play widespread roles in regulating development in both invertebrates and vertebrates constitute the Fibroblast Growth Factor (FGF) and type beta Transforming Growth Factor (TGF beta). The latest research literature about the role and fate of these Growth factors and their influence in the craniofacial bone growth ad development is reviewed.

[Infantile hydrocephalus: long-term results in 102 patients and the importance of neurosonography]. / Hidrocefalia infantil: resultados tardios em 102 pacientes e importância da neuro-sonografia.

A personal series (in 94% of the cases) of 102 children who underwent 170 procedures (1.66 procedures/patient) for hydrocephalus has been followed for 5 1/2 years (Jan-83 to June-88). Most of the children were under two years of age (80%) and in these cases brain sonography was the examination of choice for both diagnosis and follow-up (307 examinations, 4.4 per patient). Only occasionally was computed tomography necessary for better study in these cases. Our results suggest that there was no significant difference between our cases and those published in the literature concerning the number or procedures/patient (1.66)., infection rate (5.2%), mortality rate (6.8%) and intellectual performance. We recommend the use of brain sonography both in diagnosis and follow-up studies for hydrocephalic children since this examination is innocuous, inexpensive and easy to perform by neurosurgeons. Also it provides a good interaction between the examiner, the child and the parents, which is of utmost importance for the comprehension of the disease by the parents and early diagnosis of complications by the neurosurgeon.