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1.
Epidemiol Infect ; 152: e77, 2024 May 10.
Article in English | MEDLINE | ID: mdl-38724258

ABSTRACT

This study compared the likelihood of long-term sequelae following infection with SARS-CoV-2 variants, other acute respiratory infections (ARIs) and non-infected individuals. Participants (n=5,630) were drawn from Virus Watch, a prospective community cohort investigating SARS-CoV-2 epidemiology in England. Using logistic regression, we compared predicted probabilities of developing long-term symptoms (>2 months) during different variant dominance periods according to infection status (SARS-CoV-2, other ARI, or no infection), adjusting for confounding by demographic and clinical factors and vaccination status. SARS-CoV-2 infection during early variant periods up to Omicron BA.1 was associated with greater probability of long-term sequalae (adjusted predicted probability (PP) range 0.27, 95% CI = 0.22-0.33 to 0.34, 95% CI = 0.25-0.43) compared with later Omicron sub-variants (PP range 0.11, 95% CI 0.08-0.15 to 0.14, 95% CI 0.10-0.18). While differences between SARS-CoV-2 and other ARIs (PP range 0.08, 95% CI 0.04-0.11 to 0.23, 95% CI 0.18-0.28) varied by period, all post-infection estimates substantially exceeded those for non-infected participants (PP range 0.01, 95% CI 0.00, 0.02 to 0.03, 95% CI 0.01-0.06). Variant was an important predictor of SARS-CoV-2 post-infection sequalae, with recent Omicron sub-variants demonstrating similar probabilities to other contemporaneous ARIs. Further aetiological investigation including between-pathogen comparison is recommended.


Subject(s)
COVID-19 , Respiratory Tract Infections , SARS-CoV-2 , Humans , England/epidemiology , COVID-19/epidemiology , COVID-19/virology , Male , Female , Middle Aged , Prospective Studies , Adult , Respiratory Tract Infections/virology , Respiratory Tract Infections/epidemiology , Aged , Young Adult , Adolescent
3.
Clin Radiol ; 75(8): 599-605, 2020 08.
Article in English | MEDLINE | ID: mdl-32593409

ABSTRACT

AIM: To determine the incidence of possible COVID-19-related lung changes on preoperative screening computed tomography (CT) for COVID-19 and how their findings influenced decision-making. To also to determine whether the patients were managed as COVID-19 patients after their imaging findings, and the proportion who had SARS-CoV2 reverse transcriptionpolymerase chain reaction (RT-PCR) testing. MATERIALS AND METHODS: A retrospective study was undertaken of consecutive patients having imaging prior to urgent elective surgery (n=156) or acute abdominal imaging (n=283). Lung findings were categorised according to the British Society of Thoracic Imaging (BSTI) guidelines. RT-PCR testing, management, and outcomes were determined from the electronic patient records. RESULTS: 3% (13/439) of CT examinations demonstrated findings of classic/probable COVID-19 pneumonia, whilst 4% (19/439) had findings indeterminate for COVID-19. Of the total cohort, 1.6% (7/439) subsequently had confirmed RT-PCR-positive COVID-19. Importantly, all the patients with a normal chest or alternative diagnoses on CT who had PCR testing within the next 7 days, had a negative RT-PCR (92/407). There was a change in surgical outcome in 6% (10/156) of the elective surgical cohort with no change to surgical management was demonstrated in the acute abdominal emergency cohort requiring surgery (2/283). CONCLUSION: There was a 7% (32/439) incidence of potential COVID-19-related lung changes in patients having preoperative CT. Although this altered surgical management in the elective surgical cohort, no change to surgical management was demonstrated in the acute abdominal emergency cohort requiring surgery.


Subject(s)
Betacoronavirus , Coronavirus Infections/diagnostic imaging , Pneumonia, Viral/diagnostic imaging , Preoperative Care/methods , Radiography, Thoracic/methods , Tomography, X-Ray Computed/methods , Adult , Aged , Aged, 80 and over , COVID-19 , Elective Surgical Procedures , Emergency Service, Hospital , Female , Humans , Lung/diagnostic imaging , Male , Middle Aged , Pandemics , Retrospective Studies , SARS-CoV-2 , United Kingdom , Young Adult
4.
Clin Exp Ophthalmol ; 47(6): 749-756, 2019 08.
Article in English | MEDLINE | ID: mdl-31017701

ABSTRACT

IMPORTANCE: Management of cystic bleb leak is difficult. It would be essential to look for a method to strengthen the original pathological conjunctiva and reverse bleb leak. BACKGROUND: To evaluate the long-term efficacy and safety of collagen crosslinking in patients with leaking cystic bleb. DESIGN: Prospective interventional case series at a university-based hospital. PARTICIPANTS: Twelve eyes in 12 subjects with late-onset bleb leak from cystic bleb, without indications for prompt surgical interventions were included. METHODS: The subjects underwent crosslinking with 0.1% riboflavin application to bleb surface, followed by ultraviolet irradiation for 30 minutes. The subjects were followed up at baseline and at 1 week, 1 month, 3 months, 6 months post-treatment and then every 6 months afterwards. MAIN OUTCOME MEASURES: Interval from treatment to cessation of bleb leak, recurrence rate of bleb leak and side effects of treatment. RESULTS: The mean follow-up after crosslinking was 29.33 ± 12.45 months. Bleb leak subsided in 11 (92%) of 12 patients after a single session of crosslinking, after 1 to 8 weeks (median 3 weeks). Time to leak cessation was significantly correlated with the number of prior glaucoma interventions (R = .71, P = .014). Bleb wall at 3 months was significantly thicker than at baseline (0.70 ± 0.67 vs 0.81 ± 0.62 mm, P = .008). None of the patients experienced any complications. CONCLUSIONS AND RELEVANCE: Crosslinking achieves resolution of cystic bleb leak which lasts for at least 12 months, without the need of subsequent surgical interventions. Crosslinking is a simple, non-invasive treatment for bleb leak. It aims to restore the integrity of conjunctiva.


Subject(s)
Collagen/metabolism , Conjunctiva/metabolism , Cross-Linking Reagents , Filtering Surgery/adverse effects , Glaucoma, Open-Angle/surgery , Ocular Hypotension/drug therapy , Photosensitizing Agents/therapeutic use , Adult , Aged , Aged, 80 and over , Female , Follow-Up Studies , Humans , Intraocular Pressure/physiology , Male , Middle Aged , Ocular Hypotension/etiology , Ocular Hypotension/metabolism , Ocular Hypotension/physiopathology , Photochemotherapy/methods , Prospective Studies , Riboflavin/therapeutic use , Treatment Outcome , Ultraviolet Rays
5.
Front Neurol ; 9: 432, 2018.
Article in English | MEDLINE | ID: mdl-29937752

ABSTRACT

Background: Multiple sclerosis is thought to be relatively uncommon in the Asia Pacific region with prevalence estimated between 0 and 20 per 100,000. There is reason to doubt these estimates due to the lack of data from many countries and the growing evidence of variability in prevalence across small geographic areas. This study was conducted to systematically review the population prevalence, incidence, mortality and disability progression estimates of MS within the Asia Pacific region. Methods: The systematic review was conducted on articles from 1985 till 31st July 2017 within the PubMed/MEDLINE, EMBASE, SCOPUS, and The Cochrane Library databases. The review included articles that were population-based studies conducted on patients with MS in the Asia Pacific region that reported either incidence, prevalence, mortality, or disease progression. Hospital-based studies and non-research articles were excluded to ensure that only information representative of the population was included for analysis. Data appraisal and extraction was done by independent reviewers. This review was registered with PROSPERO (ID: CRD42017082760). Findings: Of the 2,757 articles found, 16 studies were included. Information on 6 (18.75%) of 32 Asia Pacific countries was found, with data representing 8% of the total population. Prevalence estimates were available for 6 countries while estimates for incidence (3 countries), mortality (4 countries), and disease progression (2 countries) were limited. Interpretation: The lack of epidemiological data available in the Asia Pacific region creates a blind spot in the surveillance of MS which obscures the true burden of MS, causing patients to struggle to receive the resources and funding that they need.

6.
Brain Behav ; 8(1): e00897, 2018 01.
Article in English | MEDLINE | ID: mdl-29568693

ABSTRACT

Introduction: Fatigue is a common and disabling problem in patients with Parkinson's disease (PD), and there is currently no satisfactory treatment. As acupuncture has been reported to be effective in fatigue related to other conditions, we sought to evaluate its efficacy in PD. Methods: This was a single center, randomized, sham-controlled study. Forty PD patients with moderately severe fatigue were randomized to receive 5 weeks of biweekly real or sham acupuncture. The primary outcome was change on the General Fatigue score of the Multidimensional Fatigue Inventory (MFI-GF) at 5 weeks. Secondary outcomes included MFI-Total score, Unified Parkinson's Disease Rating Scale Motor score (UPDRS Motor), Parkinson's Disease Questionnaire-39 (PDQ 39), Geriatrics Depression Scale (GDS), and Epworth Sleepiness Scale ESS). All outcome measures were evaluated at baseline, 5 and 9 weeks. Results: Both groups showed significant improvements in MFI-GF and MFI-Total scores at 5 and 9 weeks, but there were no significant between-group differences. There were no improvements from baseline for PDQ 39, GDS, and ESS. Although improvements were noted for the UPDRS Motor score in the real acupuncture group, no between-group difference could be demonstrated. Conclusions: Both real and sham acupuncture are equally effective in improving PD-related fatigue, and it is likely that this is due to nonspecific or placebo effects.


Subject(s)
Acupuncture Therapy , Fatigue/therapy , Parkinson Disease/complications , Aged , Fatigue/etiology , Female , Humans , Male , Middle Aged , Pilot Projects , Surveys and Questionnaires , Treatment Outcome
7.
Eur J Neurol ; 25(4): 659-665, 2018 04.
Article in English | MEDLINE | ID: mdl-29316033

ABSTRACT

BACKGROUND AND PURPOSE: Sensory neuronopathy is a cardinal feature of cerebellar ataxia neuropathy vestibular areflexia syndrome (CANVAS). Having observed that two patients with CANVAS had small median and ulnar nerves on ultrasound, we set out to examine this finding systematically in a cohort of patients with CANVAS, and compare them with both healthy controls and a cohort of patients with axonal neuropathy. We have previously reported preliminary findings in seven of these patients with CANVAS and seven healthy controls. METHODS: We compared the ultrasound cross-sectional area of median, ulnar, sural and tibial nerves of 14 patients with CANVAS with 14 healthy controls and 14 age- and gender-matched patients with acquired primarily axonal neuropathy. We also compared the individual nerve cross-sectional areas of patients with CANVAS and neuropathy with the reference values of our laboratory control population. RESULTS: The nerve cross-sectional area of patients with CANVAS was smaller than that of both the healthy controls and the neuropathy controls, with highly significant differences at most sites (P < 0.001). Conversely, the nerve cross-sectional areas in the upper limb were larger in neuropathy controls than healthy controls (P < 0.05). On individual analysis, the ultrasound abnormality was sufficiently characteristic to be detected in all but one patient with CANVAS. DISCUSSION: Small nerves in CANVAS probably reflect nerve thinning from loss of axons due to ganglion cell loss. This is distinct from the ultrasound findings in axonal neuropathy, in which nerve size was either normal or enlarged. Our findings indicate a diagnostic role for ultrasound in CANVAS sensory neuronopathy and in differentiating neuronopathy from neuropathy.


Subject(s)
Bilateral Vestibulopathy/diagnostic imaging , Cerebellar Ataxia/diagnostic imaging , Peripheral Nerves/diagnostic imaging , Peripheral Nervous System Diseases/diagnostic imaging , Adult , Aged , Anatomy, Cross-Sectional , Axons/pathology , Female , Healthy Volunteers , Humans , Male , Middle Aged , Reflex, Vestibulo-Ocular , Sensation Disorders/diagnostic imaging , Sensation Disorders/etiology , Syndrome , Ultrasonography
8.
Dalton Trans ; 47(1): 143-149, 2017 Dec 19.
Article in English | MEDLINE | ID: mdl-29210404

ABSTRACT

A series of silica@layered double hydroxides (SiO2@Mg2Al-CO3-AMO-LDHs) have been synthesised by in situ precipitation of Mg2Al-CO3-LDH at room temperature in the presence of amorphous spherical silica particles (∼500 nm). We have systematically investigated a number of synthetic parameters in order to evaluate their effects on the composition, morphological and physical properties of the isolated materials. Syntheses carried out at moderate stirring speeds (e.g. 500 rpm) were found to promote the formation of vertically aligned LDH platelets with respect to the silica surface. Addition rates of the metal solutions slower than 0.43 mmol h-1 were found to create a thicker LDH shell consisting of vertically aligned LDH platelets. When the metal solutions were added rapidly (0.86 mmol h-1), we observed that for both slow and fast stirring speeds the synthesised core-shell materials had thin LDH shells and the majority of the LDH precipitated independent of the silica, forming unbound "free" LDH.

9.
Clin Radiol ; 69(11): e454-61, 2014 Nov.
Article in English | MEDLINE | ID: mdl-25176585

ABSTRACT

Iatrogenic ureteric injury (IUI) is the leading cause of ureteric trauma and a complication of major abdominal and pelvic surgery. IUI carries significant morbidity and mortality, which can be further compounded by delayed diagnosis due to its non-specific clinical presentation. We review ureteric anatomy, types of IUI, and imaging strategies available for diagnosis. We propose an imaging protocol for prompt diagnosis and follow-up.


Subject(s)
Diagnostic Imaging , Iatrogenic Disease , Ureter/injuries , Contrast Media , Humans
10.
J Hum Hypertens ; 27(9): 545-51, 2013 Sep.
Article in English | MEDLINE | ID: mdl-23448846

ABSTRACT

High blood pressure (BP) is highly prevalent among the elderly, and even with pharmacological therapy BP is difficult to control to guideline recommended levels. Although poor compliance to therapy is associated with less BP control, little is known regarding other barriers to attaining on-treatment target BP. This study examined factors associated with achieving on-treatment target BP in 6010 hypertensive participants aged 65-84 years from the Second Australian National Blood Pressure study. Participants were followed for a median of 4.1 years, with BP monitored every 6 months. 'Target BP' was defined as a reduction of systolic/diastolic BP of at least 20/10 mm Hg and BP <160/90 mm Hg from randomization in two consecutive follow-up visits. Cox regression was used to identify factors associated with achieving target BP from a number of baseline and in-study factors. Mean BP at randomization was 168/91 mm Hg and patients had a median of 9 (range: 2-20) study visits. Target BP was achieved in 50% of patients. Demographic factors associated with achieving target BP were male gender, living in a regional area; and clinical factors included history of antihypertensive therapy, increased plasma creatinine, lower pretreatment pulse pressure and in-study use of multiple BP-lowering drugs. Those aged >80 years and seeking care from multiple doctors (hazard ratio 0.40, 95% confidence interval 0.36-0.45, P<0.001) were less likely to achieve target BP. These findings identify clinical markers that can be targeted for intervention, but also demographic factors related to service delivery, which may provide further opportunity for achieving better BP control in hypertensive elderly.


Subject(s)
Antihypertensive Agents/therapeutic use , Blood Pressure/physiology , Disease Management , Hypertension/drug therapy , Hypertension/physiopathology , Patient Compliance , Age Factors , Aged , Aged, 80 and over , Angiotensin-Converting Enzyme Inhibitors/pharmacology , Angiotensin-Converting Enzyme Inhibitors/therapeutic use , Antihypertensive Agents/pharmacology , Australia/epidemiology , Blood Pressure/drug effects , Diuretics/pharmacology , Diuretics/therapeutic use , Female , Follow-Up Studies , Humans , Hypertension/epidemiology , Life Style , Longitudinal Studies , Male , Prospective Studies , Sex Factors , Treatment Outcome
11.
Acta Ophthalmol ; 91(7): 604-9, 2013 Nov.
Article in English | MEDLINE | ID: mdl-22970709

ABSTRACT

Recently, there has been an increase in the use of targeted therapies for cancer treatments. Nevertheless, the ocular side-effects of the commonly used targeted agents are generally under-reported and not well studied in the literature. We conducted multiple searches in databases, including Medline, EMBASE, Cochrane Library and conference proceedings, using the following strings: 'name of targeted therapeutic agent (both generic and commercial names)' AND 'eye OR ocular OR vision OR ophthalmological'. Various targeted agents have been found to be associated with ocular side-effects due to their specific targeting of activities in the eye. Imatinib commonly causes periorbital oedema, epiphora and occasionally conjunctival haemorrhage. Cetuximab causes corneal lesions, meibomian gland dysfunction, periorbital and lid dermatitis, blepharitis and conjunctivitis. Erlotinib is related to various ocular toxicities, mainly on the ocular surface, and perifosine has been reported to be associated with severe keratitis. Bevacizumab could potentially disrupt intrinsic ocular circulation and lead to the development of thromboembolic events; there are rare reported cases of optic neuritis or optic neuropathy. Other targeted agents, such as trastuzumab, sunitinib and crizotinib, also have specific ocular toxicities. In conclusion, ocular effects of targeted agents are not uncommon in cancer patients receiving targeted therapy. Ophthalmologists should have high indexes of suspicion to diagnose and treat these complications promptly.


Subject(s)
Antineoplastic Agents/adverse effects , Eye Diseases/chemically induced , Molecular Targeted Therapy/adverse effects , Neoplasms/drug therapy , Antibodies, Monoclonal, Humanized/adverse effects , Benzamides/adverse effects , Bevacizumab , Cetuximab , Crizotinib , Erlotinib Hydrochloride , Humans , Imatinib Mesylate , Phosphorylcholine/adverse effects , Phosphorylcholine/analogs & derivatives , Piperazines/adverse effects , Pyrazoles/adverse effects , Pyridines/adverse effects , Pyrimidines/adverse effects , Quinazolines/adverse effects , Trastuzumab
12.
J Virol ; 86(24): 13653-61, 2012 Dec.
Article in English | MEDLINE | ID: mdl-23055561

ABSTRACT

The specific cell pathways involved in bovine ephemeral fever virus (BEFV) cell entry have not been determined. In this work, colocalization of the M protein of BEFV with clathrin or dynamin 2 was observed under a fluorescence microscope. To better understand BEFV entry, we carried out internalization studies with a fluorescently labeled BEFV by using a lipophilic dye, 3,30-dilinoleyloxacarbocyanine perchlorate (DiO), further suggesting that BEFV uses a clathrin-mediated endocytosis pathway. Our results suggest that clathrin-mediated and dynamin 2-dependent endocytosis is an important avenue of BEFV entry. Suppression of Rab5 or Rab7a through the use of a Rab5 dominant negative mutant and Rab7a short hairpin RNA (shRNA) demonstrated that BEFV requires both early and late endosomes for endocytosis and subsequent infection in MDBK and Vero cells. Treatment of BEFV-infected cells with nocodazole significantly decreased the M protein synthesis and viral yield, indicating that microtubules play an important role in BEFV productive infection, likely by mediating trafficking of BEFV-containing endosomes. Furthermore, BEFV infection was strongly blocked by different inhibitors of endosomal acidification, suggesting that virus enters host cells by clathrin-mediated and dynamin 2-dependent endocytosis in a pH-dependent manner.


Subject(s)
Clathrin/physiology , Dynamin II/physiology , Endocytosis/physiology , Ephemeral Fever Virus, Bovine/physiology , Microtubules/physiology , rab GTP-Binding Proteins/physiology , rab5 GTP-Binding Proteins/physiology , Animals , Base Sequence , Cattle , Cell Line , DNA Primers , rab7 GTP-Binding Proteins
13.
Appl Environ Microbiol ; 78(9): 3059-67, 2012 May.
Article in English | MEDLINE | ID: mdl-22344652

ABSTRACT

The ß-1,4-endoglucanase (EC 3.2.1.4) from the hyperthermophilic archaeon Pyrococcus horikoshii (EGPh) has strong hydrolyzing activity toward crystalline cellulose. When EGPh is used in combination with ß-glucosidase (EC 3.2.1.21), cellulose is completely hydrolyzed to glucose at high temperature, suggesting great potential for EGPh in bioethanol industrial applications. The crystal structure of EGPh shows a triosephosphate isomerase (TIM) (ß/α)(8)-barrel fold with an N-terminal antiparallel ß-sheet at the opposite side of the active site and a very short C-terminal sequence outside of the barrel structure. We describe here the function of the peripheral sequences outside of the TIM barrel core structure. Sequential deletions were performed from both N and C termini. The activity, thermostability, and pH stability of the expressed mutants were assessed and compared to the wild-type EGPh enzyme. Our results demonstrate that the TIM barrel core is essential for enzyme activity and that the N-terminal ß-sheet is critical for enzyme thermostability. Bioinformatics analyses identified potential key residues which may contribute to enzyme hyperthermostability.


Subject(s)
Cellulase/chemistry , Cellulase/genetics , Pyrococcus horikoshii/enzymology , Amino Acid Sequence , Enzyme Stability , Hot Temperature , Hydrogen-Ion Concentration , Molecular Sequence Data , Protein Conformation , Protein Stability , Protein Structure, Tertiary , Sequence Deletion
14.
PLoS One ; 6(10): e26273, 2011.
Article in English | MEDLINE | ID: mdl-22022587

ABSTRACT

BACKGROUND: Balancing animal conservation and human use of the landscape is an ongoing scientific and practical challenge throughout the world. We investigated reproductive success in female greater sage-grouse (Centrocercus urophasianus) relative to seasonal patterns of resource selection, with the larger goal of developing a spatially-explicit framework for managing human activity and sage-grouse conservation at the landscape level. METHODOLOGY/PRINCIPAL FINDINGS: We integrated field-observation, Global Positioning Systems telemetry, and statistical modeling to quantify the spatial pattern of occurrence and risk during nesting and brood-rearing. We linked occurrence and risk models to provide spatially-explicit indices of habitat-performance relationships. As part of the analysis, we offer novel biological information on resource selection during egg-laying, incubation, and night. The spatial pattern of occurrence during all reproductive phases was driven largely by selection or avoidance of terrain features and vegetation, with little variation explained by anthropogenic features. Specifically, sage-grouse consistently avoided rough terrain, selected for moderate shrub cover at the patch level (within 90 m(2)), and selected for mesic habitat in mid and late brood-rearing phases. In contrast, risk of nest and brood failure was structured by proximity to anthropogenic features including natural gas wells and human-created mesic areas, as well as vegetation features such as shrub cover. CONCLUSIONS/SIGNIFICANCE: Risk in this and perhaps other human-modified landscapes is a top-down (i.e., human-mediated) process that would most effectively be minimized by developing a better understanding of specific mechanisms (e.g., predator subsidization) driving observed patterns, and using habitat-performance indices such as those developed herein for spatially-explicit guidance of conservation intervention. Working under the hypothesis that industrial activity structures risk by enhancing predator abundance or effectiveness, we offer specific recommendations for maintaining high-performance habitat and reducing low-performance habitat, particularly relative to the nesting phase, by managing key high-risk anthropogenic features such as industrial infrastructure and water developments.


Subject(s)
Birds/physiology , Conservation of Natural Resources , Ecosystem , Nesting Behavior/physiology , Animals , Birds/growth & development , Darkness , Female , Geography , Humans , Life Cycle Stages , Models, Biological , Oviposition/physiology , Proportional Hazards Models , Reproducibility of Results , Risk Factors
15.
Ann Neurol ; 69(5): 803-10, 2011 May.
Article in English | MEDLINE | ID: mdl-21246604

ABSTRACT

OBJECTIVE: To investigate in vivo the impact of age on nigrostriatal dopamine dysfunction in Parkinson's disease (PD). METHODS: PD patients (n = 78) and healthy control subjects (n = 35) underwent longitudinal positron emission tomography assessments using 3 presynaptic dopamine markers: (1) [¹¹C](±)dihydrotetrabenazine (DTBZ), to estimate the density of the vesicular monoamine transporter type 2; (2) [¹¹C]d-threo-methylphenidate, to estimate the density of the plasma membrane dopamine transporter; and (3) 6-[¹8F]-fluoro-L-dopa, to estimate the activity of the enzyme dopa-decarboxylase. RESULTS: The study comprised 438 PD scans and 241 control scans (679 scans in total). At symptom onset, the loss of putamen DTBZ binding was substantially greater in younger compared to older PD patients (p = 0.015). Remarkably, however, the rate of progression of DTBZ binding loss was significantly slower in younger patients (p < 0.05). The estimated presymptomatic phase of the disease spanned more than 2 decades in younger patients, compared to 1 decade in older patients. INTERPRETATION: Our results suggest that, compared to older patients, younger PD patients progress more slowly and are able to endure more damage to the dopaminergic system before the first motor symptoms appear. These observations suggest that younger PD patients have more efficient compensatory mechanisms.


Subject(s)
Aging , Corpus Striatum/physiopathology , Disease Progression , Parkinson Disease/pathology , Substantia Nigra/physiopathology , Adult , Aged , Carbon Isotopes , Female , Fluorodeoxyglucose F18 , Humans , Longitudinal Studies , Male , Methylphenidate , Middle Aged , Parkinson Disease/diagnostic imaging , Positron-Emission Tomography/methods , Protein Binding/physiology , Substantia Nigra/diagnostic imaging , Tetrabenazine/analogs & derivatives , Tritium , Young Adult
16.
Virus Res ; 149(1): 71-7, 2010 Apr.
Article in English | MEDLINE | ID: mdl-20079780

ABSTRACT

By Western blot analyzes of expression of avian reovirus proteins, one unknown fragment was detected by an anti-sigmaA monoclonal antibody in virus-infected cells lysate. It was interesting to note that RNA interference against sigmaA resulted in the suppression of the unknown fragment. Using various lengths of sigmaA constructs conjugated with different tags, we present evidences to demonstrate that the fragment comes from the cleavage of sigmaA and is the larger carboxyl-terminus, termed sigmaAC. Cleavage of sigmaA simultaneously produces a smaller amino-terminus, named sigmaAN. sigmaAC could be seen early in viral infection and accumulated with time and dose of infection, indicating that the derived products are not just transient intermediates of protein degradation. The same type of cleaved products were also observed in different genotypes and serotypes of ARV as well as in different cell lines, suggesting that this intracellular modification of sigmaA is common to all ARVs. Similar localization of sigmaAC in both cytosol and nucleus with sigmaA suggested that further modification of sigmaA may be important for its function. Our evidences suggest that besides the outer capsid protein muB, sigmaA may also have post-translational cleavage which has never been reported before even in related mammalian reovirus.


Subject(s)
Host-Pathogen Interactions , Orthoreovirus, Avian/physiology , RNA-Binding Proteins/metabolism , Viral Core Proteins/metabolism , Animals , Birds , Blotting, Western , Cell Line , Chlorocebus aethiops , Cricetinae , Protein Processing, Post-Translational
17.
Aquat Toxicol ; 89(2): 82-93, 2008 Aug 29.
Article in English | MEDLINE | ID: mdl-18639348

ABSTRACT

Although it has been well established that different species of marine algae have different sensitivities to metals, our understanding of the physiological and biochemical basis for these differences is limited. This study investigated copper adsorption and internalisation in three algal species with differing sensitivities to copper. The diatom Phaeodactylum tricornutum was particularly sensitive to copper, with a 72-h IC50 (concentration of copper to inhibit growth rate by 50%) of 8.0 microg Cu L(-1), compared to the green algae Tetraselmis sp. (72-h IC50 47 microg Cu L(-1)) and Dunaliella tertiolecta (72-h IC50 530 microg Cu L(-1)). At these IC50 concentrations, Tetraselmis sp. had much higher intracellular copper (1.97+/-0.01 x 10(-13)g Cu cell(-1)) than P. tricornutum (0.23+/-0.19 x 10(-13)g Cu cell(-1)) and D. tertiolecta (0.59+/-0.05 x 10(-13)g Cu cell(-1)), suggesting that Tetraselmis sp. effectively detoxifies copper within the cell. By contrast, at the same external copper concentration (50 microg L(-1)), D. tertiolecta appears to better exclude copper than Tetraselmis sp. by having a slower copper internalisation rate and lower internal copper concentrations at equivalent extracellular concentrations. The results suggest that the use of internal copper concentrations and net uptake rates alone cannot explain differences in species-sensitivity for different algal species. Model prediction of copper toxicity to marine biota and understanding fundamental differences in species-sensitivity will require, not just an understanding of water quality parameters and copper-cell binding, but also further knowledge of cellular detoxification mechanisms.


Subject(s)
Chlorophyta/drug effects , Copper/toxicity , Diatoms/drug effects , Water Pollutants, Chemical/toxicity , Chlorophyta/growth & development , Chlorophyta/ultrastructure , Copper/analysis , Diatoms/growth & development , Diatoms/ultrastructure , Microscopy, Electron, Transmission , Species Specificity , Water Pollutants, Chemical/analysis
18.
Clin Exp Pharmacol Physiol ; 28(8): 663-7, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11473534

ABSTRACT

1. The second Australian National Blood Pressure Study (ANBP2) is an outcome trial of the treatment of hypertension in the elderly conducted entirely in general practices across Australia. Prior to ANBP2, no study of this size and nature had been undertaken in Australian general practice and the response of General Practitioners (GPs) to becoming involved in long-term cardiovascular research was unknown. 2. Academic departments and Divisions of General Practice were approached to support the project. General Practitioners were approached by letter of invitation and contacted by a regional medical coordinator (RMC) either at a face-to-face meeting or by telephone. 3. At the close of recruitment to ANBP2, 1938 GPs from 950 practices had registered as investigators. Sixty-two Divisions of General Practice were approached to support the study in five mainland Australian states with 39 (63%) participating, although participation by state was highly variable (range: 18-100%). Thirty divisional or promotional dinner meetings were held, with 56% (368/658) of those attending registering as investigators. Of the 8098 GPs sent a letter of invitation to participate in the study, 1357 (17%) expressed interest and eventually enrolled as investigators, ranging from 8% in Queensland to 28% in New South Wales. Ninety-six per cent of GPs who had a personal face-to-face contact (696/724) with the RMC registered in the study. 4. The GP recruitment phase of ANBP2 has been successfully completed. Peer-to-peer recruitment was the most successful strategy; however, success varied between states. General Practitioner recruitment to long-term clinical trials appears to be successful with a multifactorial approach focusing on peer-to-peer recruitment.


Subject(s)
Hypertension/therapy , Physicians, Family , Research , Aged , Australia , Blood Pressure , Health Services for the Aged , Humans , Hypertension/physiopathology , Workforce
19.
Am J Respir Crit Care Med ; 163(7): 1683-92, 2001 Jun.
Article in English | MEDLINE | ID: mdl-11401894

ABSTRACT

Here we report the effects of gentamicin treatment on cystic fibrosis transmembrane regulator (CFTR) production and function in CF airway cells and patients with CF with premature stop mutations. Using immunocytochemical and functional [6-methoxy-N- (3-sulfopropyl) quinolinium (SPQ)-based] techniques, ex vivo exposure of airway cells from stop mutation CF patients led to the identification of surface-localized CFTR in a dose-dependent fashion. Next, five patients with CF with stop mutations and five CF control subjects were treated with parenteral gentamicin for 1 wk, and underwent repeated in vivo measures of CFTR function (nasal potential difference [PD] measurements and sweat chloride [Cl(-)] testing). During the treatment period, the number of nasal PD readings in the direction of Cl(-) secretion was increased approximately 3-fold in the stop mutation patient group compared with controls (p < 0.001), and four of five stop mutation patients with CF had at least one reading during gentamicin treatment with a Cl(-) secretory response of more than -5 mV (hyperpolarized). A response of this magnitude was not seen in any of the CF control subjects (p < 0.05). In an independent series of experiments designed to test the ability of repeat nasal PDs to detect wild-type CFTR function, evidence of Cl(-) secretion was seen in 88% of control (non-CF) nasal PDs, and 71% were more than -5 mV hyperpolarized. Together, these results suggest that gentamicin treatment can suppress premature stop mutations in airway cells from patients with CF, and produce small increases in CFTR Cl(-) conductance (as measured by the nasal PD) in vivo.


Subject(s)
Codon, Nonsense/drug effects , Cystic Fibrosis Transmembrane Conductance Regulator/genetics , Cystic Fibrosis/genetics , Gentamicins/pharmacology , Adolescent , Adult , Cells, Cultured , Chlorides/metabolism , Cystic Fibrosis/metabolism , Cystic Fibrosis/physiopathology , Cystic Fibrosis Transmembrane Conductance Regulator/biosynthesis , Cystic Fibrosis Transmembrane Conductance Regulator/physiology , Female , Gentamicins/administration & dosage , Humans , Infusions, Intravenous , Male , Membrane Potentials , Microscopy, Fluorescence , Nasal Mucosa/metabolism , Nasal Mucosa/physiopathology
20.
Med Educ ; 35(5): 495-504, 2001 May.
Article in English | MEDLINE | ID: mdl-11328521

ABSTRACT

The last 10 years has been an interesting time for Australian medical education despite reduced funding. WORKFORCE: There are five main workforce trends: a rural/urban maldistribution, a need for more specialists, public hospital staffing difficulties, increasing female practitioners and under-representation of indigenous practitioners. ISSUES FACING THE DEANS: Lack of resources is a problem facing Deans, with pressure for clinical service in teaching hospitals. Entrepreneurial activities have been undertaken including the enrollment of overseas students. Medical schools have also responded to important government initiatives. DEVELOPMENTS IN MEDICAL EDUCATION: Australia's 11 medical schools have undergone significant reform in the last decade. There is a mix of four (graduate), five and six year courses. AUSTRALIA'S NEW MEDICAL SCHOOL: James Cook University opened the first medical school in northern Australia in 2000. The School admits students from rural, northern Australian and indigenous backgrounds. It has a strong regional mission. RURAL AND COMMUNITY-BASED EDUCATION: Government funding to address the maldistribution of the workforce has led to the establishment of rural clubs, Departments of Rural Health and community-based programs. THE FIRST TWO POSTGRADUATE YEARS: There have been recent moves to improve education in the two years following graduation. This includes the initiation of national projects in curriculum and assessment. POSTGRADUATE AND CONTINUING MEDICAL EDUCATION: Postgraduate programs in Australia are being reformed to build on the changes in undergraduate education. CME is also under review. CONCLUSION: Australian medical educators should build on the recent reforms and take on some of the new directions in medical education.


Subject(s)
Delivery of Health Care , Education, Graduate/organization & administration , Education, Medical, Undergraduate/organization & administration , Australia , Curriculum , Education, Graduate/trends , Education, Medical, Undergraduate/trends , Ethnicity , Female , Humans , Male , Physicians, Women/statistics & numerical data , Rural Health
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