Unfolded p53 in non-neuronal cells supports bacterial etiology of Alzheimer's disease.

Alzheimer's disease has proven to be largely intractable to treatment, despite years of research, and numerous trials of therapies that target the hallmarks of the disease - amyloid plaques and neurofibrillary tangles. The etiology of Alzheimer's disease remains elusive. There is a growing body of evidence for an infectious trigger of Alzheimer's disease, and, in particular, the focus has been on the oral pathogen Porphyromonas gingivalis (P. gingivalis). Reports of the expression of a misfolded form of p53 in non-neuronal cells (fibroblasts, peripheral blood mononuclear cells, and B cells) and serum, which appears several years before clinical symptoms manifest, may provide further support for the role of bacteria in general, and P. gingivalis in particular, in the initiation of the disease. This review presents a model of the pathway from initial oral infection with P. gingivalis to amyloid plaque formation and neuronal degeneration, via the steps of chronic periodontitis; secretion of the inflammagens lipopolysaccharide and gingipains into the bloodstream; induction of an inflammatory response in both peripheral cells and tissues; disruption of the blood-brain barrier, and entry into the central nervous system of the inflammagens and the P. gingivalis bacteria themselves. In this model, the misfolded p53 (or "unfolded p53"; up53) is induced in non-neuronal cells and upregulated in serum as a result of oxidative stress due to lipopolysaccharide from P. gingivalis. up53 is therefore a potential biomarker for early diagnosis of the presence of a causative agent of Alzheimer's disease. Fastidious dental hygiene and aggressive antibiotic treatment may prevent the patient progressing to clinical Alzheimer's disease if serum up53 is detected at this pre-symptomatic stage.

Fungal Neurotoxins and Sporadic Amyotrophic Lateral Sclerosis.

We review several lines of evidence that point to a potential fungal origin of sporadic amyotrophic lateral sclerosis (ALS). ALS is the most common form of motor neuron disease (MND) in adults. It is a progressive and fatal disease. Approximately 90% cases of ALS are sporadic, and 5-10% are due to genetic mutations (familial). About 25 genes implicated in familial ALS have been identified so far, including SOD1 and TARDBP, the gene encoding 43 kDa transactive response (TAR) DNA-binding protein (TDP-43). Despite intensive research over many decades, the aetiology of sporadic ALS is still unknown. An environmental cause, including grass or soil-associated fungal infections, is suggested from a range of widely diverse lines of evidence. Clusters of ALS have been reported in soccer players, natives of Guam and farmers. Grass-associated fungi are known to produce a range of neurotoxins and, in symbiotic associations, high levels of fungal SOD1. Exposure of neurons to fungal neurotoxins elicits a significant increase in glutamate production. High levels of glutamate stimulate TDP-43 translocation and modification, providing a link between fungal infection and one of the molecular and histologic hallmarks of sporadic ALS. A recent study provided evidence of a variety of fungi in the cerebrospinal fluid and brain tissue of ALS patients. This review provides a rational explanation for this observation. If a fungal infection could be confirmed as a potential cause of ALS, this could provide a straightforward treatment strategy for this fatal and incurable disease.

Identification of breast cancer-associated lipids in scalp hair.

A correlation between the presence of breast cancer and a change in the synchrotron-generated X-ray diffraction (XRD) pattern of hair has been reported in several publications by different groups, and on average XRD-based assays detect around 75% of breast cancer patients in blinded studies. To date, the molecular mechanisms leading to this alteration are largely unknown. We have determined that the alteration is likely to be due to the presence of one or more breast cancer-associated phospholipids. Further characterization of these lipids could be used to develop a novel, sensitive and specific screening test for breast cancer, based on hair initially, and potentially extendable to other biological samples.

Gene silencing of IL-12 in dendritic cells inhibits autoimmune arthritis.

BACKGROUND: We have previously demonstrated that immune modulation can be accomplished by administration of gene silenced dendritic cells (DC) using siRNA. In this study, we demonstrate the therapeutic utilization of shRNA-modified DC as an antigen-specific tolerogenic vaccine strategy for autoimmune arthritis. METHODS: A shRNA that specifically targets IL-12 p35 was designed and cloned into a plasmid vectors (IL-12 shRNA). Bone marrow-derived DC from DBA/1 mice were transfected with the IL-12 shRNA construct in vitro. Mice with collagen II (CII)-induced arthritis (CIA) were treated with the modified DCs expressing the shRNA. Recall response and disease progression were assessed. RESULTS: After gene silencing of IL-12 in DC, DC were shown to selectively inhibit T cell proliferation on recall responses and in an MLR. In murine CIA, we demonstrated that administration of IL-12 shRNA-expressing DC that were pulsed with CII inhibited progression of arthritis. The therapeutic effects were evidenced by decreased clinical scores, inhibition of inflammatory cell infiltration in the joint, and suppression of T cell and B cell responses to CII. CONCLUSION: We demonstrate a novel tolerance-inducing protocol for the treatment of autoimmune inflammatory joint disease in which the target antigen is known, utilizing DNA-directed RNA interference.

Detecting the presence of denatured human serum albumin in an adsorbed protein monolayer using TOF-SIMS.

We demonstrate the application of time-of-flight secondary ion mass spectrometry (TOF-SIMS) in conjunction with multivariate statistics to differentiate trace levels of denatured proteins in adsorbed monolayers; specifically, human serum albumin (HSA) on oxidized silicon substrates. Subtle differences in protein conformation due to thermal denaturation of HSA, unable to be determined by dynamic light scattering nor circular dichroism, were differentiated by TOF-SIMS. The fragmentation pattern is highly sensitive to protein conformation, allowing assessment of relative amounts of proteins in mixtures and quantifying amounts of denatured protein in a sample. Discussion is presented on ascribing orientation and conformational differences between samples based upon TOF-SIMS spectra. This has implications for detecting denatured protein in biotechnology and medical applications.

Characterization of a Test for Invasive Breast Cancer Using X-ray Diffraction of Hair-Results of a Clinical Trial.

OBJECTIVE: To assess the performance of a test for breast cancer utilizing synchrotron x-ray diffraction analysis of scalp hair from women undergoing diagnostic radiology assessment. DESIGN AND SETTING: A double-blinded clinical trial of women who attended diagnostic radiology clinics in Australia. PATIENTS: 1796 women referred for diagnostic radiology, with no previous history of cancer. MAIN OUTCOME MEASURES: Sensitivity, specificity and accuracy of the hair test analysis compared to the gold standard of imaging followed by biopsy where indicated. RESULTS: The hair-based assay had an overall accuracy of >77% and a negative predictive value of 99%. For all women, the sensitivity of both mammography and X-ray diffraction alone was 64%, but when used together the sensitivity rose to 86%. The sensitivity of the hair test for women under the age of 70 was 74%. CONCLUSION: In this large population trial the association between the presence of breast cancer and an altered hair fibre X-ray diffraction pattern previously reported has been confirmed. It appears that mammography and X-ray diffraction of hair detect different populations of breast cancers, and are synergistic when used together.

Diagnosis of breast cancer by X-ray diffraction of hair.

This article presents the results of analyses of hair fibers from women with breast cancer using synchrotron-derived X-ray diffraction. These diffraction patterns contained a new feature superimposed on the normal diffraction pattern of alpha-keratin. The feature appeared as a ring with a molecular spacing determined to be 4.76 +/- 0.07 nm. This feature was not present in the diffraction patterns of hair from women without breast cancer as assessed by other routine clinical diagnostic techniques. Furthermore, different hairs from the same subject analysed on two different synchrotron beamlines give remarkably consistent diffraction patterns. Previous studies by other investigators have suggested that analysis of X-ray diffraction patterns of hair can reveal the presence of breast cancer in clinical and preclinical trials. This finding, however, has not been independently confirmed. The methodologies of sample handling, sample exposure and image analysis are known to be vital. We discuss some of these issues and provide a detailed description of the methodology employed for the sample handling and image analysis and new methodologies developed from this work. We conclude that X-ray diffraction of hair has the potential to provide a non-invasive test for the presence of breast cancer.