A satellite RNA of barley yellow dwarf virus contains a novel hammerhead structure in the self-cleavage domain

An RNA molecule with properties of a satellite RNA was found in an isolate of barley yellow dwarf virus (BYDV), RPV serotype. It is 322 nucleotides long, single-stranded, and does not hybridize to the viral genome. Dimers of the RNA, which presumably represent replicative intermediates, were able to self-cleave into monomers. In vitro transcripts from cDNA clones were capable of self-cleavage in both the plus (encapsidated) and minus orientations. The sequence flanking the minus strand cleavage site contained a consensus " hammerhead" structure, similar to those found in other self-cleaving satellite RNAs. Although related to the hammerhead structure, sequences flanking the plus strand termini showed differences from the consensus and may be folded into a different structure containing a pseudoknot. © 1991.

A novel energy efficient controllable stiffness joint

Achieving energy efficient legged locomotion is an important goal for the future of robot mobility. This paper presents a novel joint for legged locomotion that is energy efficient for two reasons. The first reason is the configuration of the elastic elements and actuator which we show analytically has lower energy losses than the typical arrangement. The second is that the joint stiffness, and hence stance duration, is controllable without requiring any energy from the actuator. Further, the joint stiffness can be changed significantly during the flight phase, from zero to highly rigid. Results obtained from a prototype hopper, demonstrate that the joint allows continuous and peak hopping via torque control. The results also demonstrate that the hopping frequency can be varied between 2.2Hz and 4.6Hz with associated stance duration of between 0.35 and 0.15 seconds.

A novel method for analysing lighting variance

Robust descriptor matching across varying lighting conditions is important for vision-based robotics. We present a novel strategy for quantifying the lighting variance of descriptors. The strategy works by utilising recovered low dimensional mappings from Isomap and our measure of the lighting variance of each of these mappings. The resultant metric allows different descriptors to be compared given a dataset and a set of keypoints. We demonstrate that the SIFT descriptor typically has lower lighting variance than other descriptors, although the result depends on semantic class and lighting conditions.

A novel protecting group methodology for syntheses using nitroxides

The methoxyamine group represents an ideal protecting group for the nitroxide moiety. It can be easily and selectively introduced in high yield (typically >90%) to a range of functionalised nitroxides using FeSO4.7H2O and H2O2 in DMSO. Its removal is readily achieved under mild conditions in high yield (70-90%) using mCPBA in a Cope-type elimination process.

Oral immunization with a novel lipid-based adjuvant protects against genital Chlamydia infection

Oral immunization is attractive as a delivery route because it is needle-free and useful for rapid mass vaccination programs to target pandemics or bioterrorism. This potential has not been realized for human vaccination, due to the requirement of large antigen doses and toxic (to humans) adjuvants to overcome the induction of oral tolerance and potential degradation of antigens in the stomach. To date, only oral vaccines based on live attenuated organisms have been approved for human use. In this study we describe the use of a lipid-based delivery system/adjuvant, Lipid C, for oral immunization to protect mice against genital tract chlamydial infection. Lipid C is formulated from food-grade purified and fractionated triglycerides. Bacterial shedding following vaginal challenge with Chlamydia muridarum was reduced by 50% in female mice orally immunized with the chlamydial major outer membrane protein (MOMP) formulated in Lipid C, protection equivalent to that seen in animals immunized with MOMP admixed with both cholera toxin (CT) and CpG oligodeoxynucleotides (CpG-ODN). Protection was further enhanced when MOMP, CT and CpG were all combined in the Lipid C matrix. Protection correlated with production of gamma interferon (IFN) by splenic T cells, a serum MOMP-specific IgG response and low but detectable levels of MOMP-specific IgA in vaginal lavage.

Transcutaneous immunization with a novel lipid-based adjuvant protects against Chlamydia genital and respiratory infections

Mucosal adjuvants are important to overcome the state of immune tolerance normally associated with mucosal delivery and to enhance adaptive immunity to often-weakly immunogenic subunit vaccine antigens. Unfortunately, adverse side effects of many experimental adjuvants limit the number of adjuvants approved for vaccination. Lipid C is a novel, non-toxic, lipid oral vaccine-delivery formulation, developed originally for oral delivery of the live Mycobacterium bovis Bacille Calmette-Guerin (BCG) vaccine. In the present study, murine models of chlamydial respiratory and genital tract infections were used to determine whether transcutaneous immunization (TCI) with Lipid C-incorporated protein antigens could elicit protective immunity at the genital and respiratory mucosae. BALB/c mice were immunized transcutaneously with Lipid C containing the chlamydial major outer membrane protein (MOMP), with and without addition of cholera toxin and CpG-ODN 1826 (CT/CpG). Both vaccine combinations induced mixed cell-mediated and mucosal antibody immune responses. Immunization with Lipid C-incorporated MOMP (Lipid C/MOMP), either alone or with CT/CpG resulted in partial protection following live challenge with Chlamydia muridarum as evidenced by a significant reduction in recoverable Chlamydia from both the genital secretions and lung tissue. Protection induced by immunization with Lipid C/MOMP alone was not further enhanced by the addition of CT/CpG. These results highlight the potential of Lipid C as a novel mucosal adjuvant capable of targeting multiple mucosal surfaces following TCI. Protection at both the respiratory and genital mucosae was achieved without the requirement for potentially toxic adjuvants, suggesting that Lipid C may provide a safe effective mucosal adjuvant for human vaccination.

Typing early Australian healthcare-associated MRSA : confirmation of major clones and emergence of ST1-MRSA-IV and novel ST2249-MRSA-III

AIMS: To investigate the evolutionary origins of Australian healthcare-associated (HCA) methicillin-resistant Staphylococcus aureus (MRSA) strains from a panel of historical isolates typed using current genotyping techniques. METHODS: Nineteen MRSA isolates from 1965 to 1981 were examined and antibiotic susceptibility profiles determined. Genetic characterisation included real-time (RT) polymerase chain reaction (PCR) assays to identify single nucleotide polymorhpism (SNP) clonal complexes (SNP CC) and sequence type (SNP ST), multi locus sequence typing (MLST) and staphylococcal chromosomal cassette mec typing. RESULTS: All SNP CC30 isolates belonged to a novel sequence type, ST2249. All SNP CC239 isolates were confirmed as ST239-MRSA-III, except for a new single locus variant of ST239, ST2275. A further new type, ST2276, was identified. CONCLUSIONS: The earliest MRSA examined from 1965 was confirmed as ST250-MRSA-I, consistent with archaic European types. Identification of ST1-MRSA-IV in 1981 is the earliest appearance of this clinically important lineage which manifested in Australia and the United States in the 1990s. A previously unknown multi-resistant clone, ST2249-MRSA-III, was identified from 1973. Gentamicin resistance first appeared in this novel strain from 1976 and not ST239 as previously suspected. Thus, ST2249 was present in the earliest phase of the HCA MRSA epidemic in eastern Australia and was perhaps related to the emergence of the globally epidemic strain ST239.

Constructing subjects and making experts : reading the politics of the psychotherapy novel

This paper examines the ideological and political basis of the practice of psychotherapy in contemporary culture. Psychotherapy is argued to be both inherently political and intimately concerned with the construction of subjectivity. These arguments are examined through interrogating the representation of psychotherapy in the works of Lindner ( The Fifty-Minute Hour , Bantam, New York, 1955) and particularly in Yalom's fictional text Lying on the Couch (HarperPerennial, New York, 1996). The implications within psychotherapy for representing normality, negotiating power, and locating and constructing subjectivity are highlighted through the critical treatment of these texts.

A novel method using intranasal delivery of EdU demonstrates that accessory olfactory ensheathing cells respond to injury by proliferation

Olfactory ensheathing cells (OECs) play an important role in the continuous regeneration of the primary olfactory nervous system throughout life and for regeneration of olfactory neurons after injury. While it is known that several individual OEC subpopulations with distinct properties exist in different anatomical locations, it remains unclear how these different subpopulations respond to a major injury. We have examined the proliferation of OECs from one distinct location, the peripheral accessory olfactory nervous system, following large-scale injury (bulbectomy) in mice. We used crosses of two transgenic reporter mouse lines, S100ß-DsRed and OMP-ZsGreen, to visualise OECs, and main/accessory olfactory neurons, respectively. We surgically removed one olfactory bulb including the accessory olfactory bulb to induce degeneration, and found that accessory OECs in the nerve bundles that terminate in the accessory olfactory bulb responded by increased proliferation with a peak occurring 2 days after the injury. To label proliferating cells we used the thymidine analogue ethynyl deoxyuridine (EdU) using intranasal delivery instead of intraperitoneal injection. We compared and quantified the number of proliferating cells at different regions at one and four days after EdU labelling by the two different methods and found that intranasal delivery method was as effective as intrapeitoneal injection. We demonstrated that accessory OECs actively respond to widespread degeneration of accessory olfactory axons by proliferating. These results have important implications for selecting the source of OECs for neural regeneration therapies and show that intranasal delivery of EdU is an efficient and reliable method for assessing proliferation of olfactory glia.

Longitudinal assessment of neuropathy in type 1 diabetes using novel ophthalmic markers (LANDMark) : study design and baseline characteristics

Aims Corneal nerve morphology and corneal sensation threshold have recently been explored as potential surrogate markers for the evaluation of diabetic neuropathy. We present the baseline findings of the ‘Longitudinal Assessment of Neuropathy in type 1 Diabetes using novel ophthalmic Markers’(LANDMark) study. Methods The LANDMark study is a 4-year, two-site, natural history study of three participant groups: type 1 diabetes with neuropathy (T1W), type 1 diabetes without neuropathy (T1WO) and control participants without diabetes or neuropathy. All participants undergo a detailed annual assessment of neuropathy including corneal nerve parameters measured using corneal confocal microscopy and corneal sensitivity measured using non-contact corneal aesthesiometry. Results 76 T1W, 166 T1WO and 154 control participants were enrolled into the study. Corneal sensation threshold (mbars) was significantly higher (i.e. sensitivity was lower) in T1W (1.0 ± 1.1) than T1WO (0.7 ± 0.7) and controls (0.6 ± 0.4) (p < 0.001), with no difference between T1WO and controls. Corneal nerve fibre length was lower in T1W (14.0 ± 6.4 mm/mm2) compared to T1WO (19.1 ± 5.8 mm/mm2) and controls (23.2 ± 6.3 mm/mm2) (p < 0.001). Corneal nerve fibre length was lower in T1WO compared to controls. Conclusions The LANDMark baseline findings confirm a reduction in corneal sensitivity only in Type 1 patients with neuropathy. However, corneal nerve fibre length is reduced even in Type 1 patients without neuropathy with an even greater deficit in Type 1 patients with neuropathy.

The role of the arachidonic acid pathway in NSCLC development and progression : novel approaches for therapeutic intervention

Arachidonic acid metabolism through cyclooxygenase (COX), lipoxygenase (LOX) and cytochrome P-450 epoxygenase (EPOX) pathways is responsible for the formation of biologically active eicosanoids, including prostanoids, leukotrienes, hydroxyeicosatetraenoic acid, epoxyeicosatrienoic acid and hydroperoxyeicosatetraenoic acids. Altered eicosanoid expression levels are commonly observed during tumour development and progression of a range of malignancies, including non-small cell lung cancer (NSCLC). Arachidonic acid-derived eicosanoids affect a range of biological phenomena to modulate tumour processes such as cell growth, survival, angiogenesis, cell adhesion, invasion and migration and metastatic potential. Numerous studies have demonstrated that eicosanoids modulate NSCLC development and progression, while targeting these pathways has generally been shown to inhibit tumour growth/progression. Modulation of these arachidonic acid-derived pathways for the prevention and/or treatment of NSCLC has been the subject of significant interest over the past number of years, with a number of clinical trials examining the potential of COX and LOX inhibitors in combination with traditional and novel molecular approaches. However, results from these trials have been largely disappointing. Furthermore, enthusiasm for the use of selective COX-2 inhibitors for cancer prevention/treatment waned, due to their association with adverse cardiovascular events in chemoprevention trials. While COX and LOX targeting may both retain promise for NSCLC prevention and/or treatment, there is an urgent need to understand the downstream signalling mechanisms through which these and other arachidonic acid-derived signalling pathways mediate their effects on tumourigenesis. This will allow for development of safer and potentially more effective strategies for NSCLC prevention and/or treatment. Chemoprevention studies with PGI2 analogues have demonstrated considerable promise, while binding to/signalling through PGE2 receptors have also been the subject of interest for NSCLC treatment. In this chapter, the role of the eicosanoid signalling pathways in non-small cell lung cancer will be discussed. In particular, the effect of the eicosanoids on tumour cell proliferation, their roles in induction of cell death, effects on angiogenesis, migration, invasion and their regulation of the immune response will be assessed, with signal transduction pathways involved in these processes also discussed. Finally, novel approaches targeting these arachidonic acid-derived eicosanoids (using pharmacological or natural agents) for chemoprevention and/or treatment of NSCLC will be outlined. Elucidating the molecular mechanisms underlying the effects of specific or general arachidonic acid pathway modulators may lead to the design of biologically and pharmacologically targeted therapeutic strategies for NSCLC prevention/treatment, which may be used alone or in combination with conventional therapies.

Exploration of novel routes to azo-linked oligoporphyrins

This research explored new ways of chemically combining porphyrins, which are vital biomolecules, to produce new pigments known as azoporphyrins, for applications in advanced technologies. Although the final targets have not yet been realized, numerous novel compounds and known compounds lacking experimental data in the literature were fully characterised by a range of techniques. The data will facilitate subsequent studies of other novel routes to azoporphyrins and related molecules.

Assessment of diabetic neuropathy using novel corneal markers.

Diabetic peripheral neuropathy is a debilitating condition that affects approximately 50 per cent of diabetic patients. The symptoms of neuropathy include numbness and tingling or pain in the arms and legs. If left untreated, patients with numbness might develop foot ulcers, which might ultimately require foot amputation. Currently the only method of directly examining peripheral nerves is to conduct skin punch biopsies, which are uncomfortable and invasive.