63 research outputs found

    Rearrangement of {α-P2W15} to {PW6} moieties during the assembly of transition-metal-linked polyoxometalate clusters

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    We report the formation of two polyoxotungstates of the general formula [M6(PW6O26)(α-P2W15O56)2(H2O)2]23− (M = CoII or MnII), which contain {PW6} fragments generated from the [P2W15O56]12− precursor, which demonstrates for the first time the transformation of a Dawson lacunae into a Keggin lacunary building block. Solution analysis of the clusters has been conducted via electrospray ionisation mass spectrometry

    Facilitating access to health research through a participatory research register:a feasibility study in outpatient clinics

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    Abstract Background A research register (Reach West) has been established to facilitate recruitment of people and patients to health-related research. We conducted a prospective feasibility study to investigate the practicality of recruiting through outpatient clinics. Methods Patients over 18 years of age attending dental, eye or oncology outpatient clinics in an acute hospital in the West of England were provided with the opportunity to participate in Reach West. In Phase I, recruitment packs were handed to clinic attendees who could place completed consent forms in secure drop-box or return them later on-line or by post. In Phase II, recruitment packs were posted directly to patients with consent forms to be returned by post or on-line. Response rates by age, sex, postcode (for level of deprivation), and clinic type were recorded for those agreeing to participate on paper or on-line. Results In Phase I, 2,314 of 4,500 (51.4%) of recruitment packs were handed out to clinic attendees, and 114 (5%) consented to join Reach West. In Phase II, 7,173 of 9000 packs were posted (79.7%), and 387 (5.4%) consented to participate. The overall consent rate was 6% (580), with the majority doing so on paper (87%) rather than on-line. The sample was balanced by sex, but mostly comprised people over 50 years located in less deprived postcodes. Non-staff costs for postal recruitment were lower than hand-outs in clinic (£6.84 compared with £8.05 per participant). Conclusions Recruiting participants to the Reach West register was feasible among those with oncology, dental or eye outpatient appointments by post or with packs given out in the clinic. Response rates were similar to those achieved for other registers. Recruitment of participants can be achieved through outpatient clinics but other strategies will also be required to attract large numbers of participants and more diverse populations

    Facilitating access to health research through a participatory research register:a feasibility study in outpatient clinics

    Get PDF
    Abstract Background A research register (Reach West) has been established to facilitate recruitment of people and patients to health-related research. We conducted a prospective feasibility study to investigate the practicality of recruiting through outpatient clinics. Methods Patients over 18 years of age attending dental, eye or oncology outpatient clinics in an acute hospital in the West of England were provided with the opportunity to participate in Reach West. In Phase I, recruitment packs were handed to clinic attendees who could place completed consent forms in secure drop-box or return them later on-line or by post. In Phase II, recruitment packs were posted directly to patients with consent forms to be returned by post or on-line. Response rates by age, sex, postcode (for level of deprivation), and clinic type were recorded for those agreeing to participate on paper or on-line. Results In Phase I, 2,314 of 4,500 (51.4%) of recruitment packs were handed out to clinic attendees, and 114 (5%) consented to join Reach West. In Phase II, 7,173 of 9000 packs were posted (79.7%), and 387 (5.4%) consented to participate. The overall consent rate was 6% (580), with the majority doing so on paper (87%) rather than on-line. The sample was balanced by sex, but mostly comprised people over 50 years located in less deprived postcodes. Non-staff costs for postal recruitment were lower than hand-outs in clinic (£6.84 compared with £8.05 per participant). Conclusions Recruiting participants to the Reach West register was feasible among those with oncology, dental or eye outpatient appointments by post or with packs given out in the clinic. Response rates were similar to those achieved for other registers. Recruitment of participants can be achieved through outpatient clinics but other strategies will also be required to attract large numbers of participants and more diverse populations

    Gastrointestinal Parasites of Two Populations of Arctic Foxes (<em>Vulpes lagopus</em>) from Northeast Greenland

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    Parasitological examination of 275 faecal samples from Arctic foxes (Vulpes lagopus) collected at Zackenberg Valley and Karupelv Valley in north-east Greenland from 2006 to 2008 was conducted using sieving and microscopy. Overall, 125 (45.5%) samples contained parasite eggs of Taenia crassiceps, Taenia serialis, Toxascaris leonina, Eucoleus boehmi, Physalopteridae and Ancylostomatidae, and Strongyloides-like larvae. As long-term ecological studies are conducted at both sampling locations, the present findings constitute a baseline data set for further parasitological monitoring

    The Tetrodotoxin Receptor of Voltage-Gated Sodium Channels—Perspectives from Interactions with μ-Conotoxins

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    Neurotoxin receptor site 1, in the outer vestibule of the conducting pore of voltage-gated sodium channels (VGSCs), was first functionally defined by its ability to bind the guanidinium-containing agents, tetrodotoxin (TTX) and saxitoxin (STX). Subsequent studies showed that peptide μ-conotoxins competed for binding at site 1. All of these natural inhibitors block single sodium channels in an all-or-none manner on binding. With the discovery of an increasing variety of μ-conotoxins, and the synthesis of numerous derivatives, observed interactions between the channel and these different ligands have become more complex. Certain μ-conotoxin derivatives block single-channel currents partially, rather than completely, thus enabling the demonstration of interactions between the bound toxin and the channel’s voltage sensor. Most recently, the relatively small μ-conotoxin KIIIA (16 amino acids) and its variants have been shown to bind simultaneously with TTX and exhibit both synergistic and antagonistic interactions with TTX. These interactions raise new pharmacological possibilities and place new constraints on the possible structures of the bound complexes of VGSCs with these toxins

    Marine Toxins: Chemistry, Toxicity, Occurrence and Detection, with Special Reference to the Dutch Situation

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    Various species of algae can produce marine toxins under certain circumstances. These toxins can then accumulate in shellfish such as mussels, oysters and scallops. When these contaminated shellfish species are consumed severe intoxication can occur. The different types of syndromes that can occur after consumption of contaminated shellfish, the corresponding toxins and relevant legislation are discussed in this review. Amnesic Shellfish Poisoning (ASP), Paralytic Shellfish Poisoning (PSP), Diarrheic Shellfish Poisoning (DSP) and Azaspiracid Shellfish Poisoning (AZP) occur worldwide, Neurologic Shellfish Poisoning (NSP) is mainly limited to the USA and New Zealand while the toxins causing DSP and AZP occur most frequently in Europe. The latter two toxin groups are fat-soluble and can therefore also be classified as lipophilic marine toxins. A detailed overview of the official analytical methods used in the EU (mouse or rat bioassay) and the recently developed alternative methods for the lipophilic marine toxins is given. These alternative methods are based on functional assays, biochemical assays and chemical methods. From the literature it is clear that chemical methods offer the best potential to replace the animal tests that are still legislated worldwide. Finally, an overview is given of the situation of marine toxins in The Netherlands. The rat bioassay has been used for monitoring DSP and AZP toxins in The Netherlands since the 1970s. Nowadays, a combination of a chemical method and the rat bioassay is often used. In The Netherlands toxic events are mainly caused by DSP toxins, which have been found in Dutch shellfish for the first time in 1961, and have reoccurred at irregular intervals and in varying concentrations. From this review it is clear that considerable effort is being undertaken by various research groups to phase out the animal tests that are still used for the official routine monitoring programs

    Twenty two cases of canine neural angiostronglyosis in eastern Australia (2002-2005) and a review of the literature

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    Cases of canine neural angiostrongylosis (NA) with cerebrospinal fluid (CSF) evaluations in the peer-reviewed literature were tabulated. All cases were from Australia. A retrospective cohort of 59 dogs was contrasted with a series of 22 new cases where NA was diagnosed by the presence of both eosinophilic pleocytosis and anti-Angiostrongylus cantonensis immunloglobulins (IgG) in CSF, determined by ELISA or Western blot. Both cohorts were drawn from south east Queensland and Sydney. The retrospective cohort comprised mostly pups presented for hind limb weakness with hyperaesthesia, a mixture of upper motor neurone (UMN) and lower motor neurone (LMN) signs in the hind limbs and urinary incontinence. Signs were attributed to larval migration through peripheral nerves, nerve roots, spinal cord and brain associated with an ascending eosinophilic meningo-encephomyelitis. The contemporary cohort consisted of a mixture of pups, young adult and mature dogs, with a wider range of signs including (i) paraparesis/proprioceptive ataxia (ii) lumbar and tail base hyperaesthesia, (iii) multi-focal central nervous system dysfunction, or (iv) focal disease with neck pain, cranial neuropathy and altered mentation. Cases were seen throughout the year, most between April and July (inclusive). There was a preponderance of large breeds. Often littermates, or multiple animals from the same kennel, were affected simultaneously or sequentially. A presumptive diagnosis was based on consistent signs, proximity to rats, ingestion/chewing of slugs or snails and eosinophilic pleocytosis. NA was diagnosed by demonstrating anti-A. cantonensis IgG in CSF. Detecting anti-A. cantonensis IgG in serum was unhelpful because many normal dogs (20/21 lb dogs; 8/22 of a hospital population) had such antibodies, often at substantial titres. Most NA cases in the contemporary series (19/22) and many pups (16/38) in the retrospective cohort were managed successfully using high doses of prednisolone and opioids. Treatment often included antibiotics administered in case protozoan encephalomyelitis or translocated bacterial meningitis was present. Supportive measures included bladder care and physiotherapy. Several dogs were left with permanent neural deficits. Dogs are an important sentinel species for NA. Human cases and numerous cases in tawny frogmouths were reported from the same regions as affected dogs over the study period
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