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1.
Proc Biol Sci ; 289(1989): 20221649, 2022 12 21.
Article in English | MEDLINE | ID: mdl-36515119

ABSTRACT

Ecosystem structure and function are increasingly threatened by changing climate, with profound effects observed globally in recent decades. Based on standardized visual censuses of reef biodiversity, we describe 27 years of community-level change for fishes, mobile macroinvertebrates and macroalgae in the Tasmanian ocean-warming hotspot. Significant ecological change was observed across 94 reef sites (5-10 m depth range) spanning four coastal regions between three periods (1992-95, 2006-07, 2017-19), which occurred against a background of pronounced sea temperature rise (+0.80°C on average). Overall, fish biomass increased, macroinvertebrate species richness and abundance decreased and macroalgal cover decreased, particularly during the most recent decade. While reef communities were relatively stable and warming was slight between the 1990s and mid-2000s (+0.12°C mean temperature rise), increased abundances of warm affinity fishes and invertebrates accompanied warming during the most recent decade (+0.68°C rise). However, significant rises in the community temperature index (CTI) were only found for fishes, invertebrates and macroalgae in some regions. Coastal warming was associated with increased fish biomass of non-targeted species in fished zones but had little effect on reef communities within marine reserves. Higher abundances of larger fishes and lobsters inside reserves appeared to negate impacts of 'thermophilization'.


Subject(s)
Ecosystem , Seaweed , Animals , Biodiversity , Invertebrates , Temperature , Fishes , Coral Reefs
2.
J Affect Disord ; 314: 325-332, 2022 10 01.
Article in English | MEDLINE | ID: mdl-35878837

ABSTRACT

BACKGROUND: Bipolar disorder (BD) is a strongly familial psychiatric disorder associated with white matter (WM) brain abnormalities. It is unclear whether such abnormalities are present in relatives without BD, and little is known about WM trajectories in those at increased genetic risk. METHODS: Diffusion magnetic resonance imaging (dMRI) data were acquired at baseline and after two years in 91 unaffected individuals with a first-degree relative with bipolar disorder (HR), and 85 individuals with no family history of mental illness (CON). All participants were aged between 12 and 30 years at baseline. We examined longitudinal change in Fractional Anisotropy (FA) using tract-based spatial statistics (TBSS). RESULTS: Compared to the CON group, HR participants showed a significant increase in FA in the right cingulum (hippocampus) (CGH) over a two-year period (p < .05, FDR corrected). This effect was more pronounced in HR individuals without a lifetime diagnosis of a mood disorder than those with a mood disorder. LIMITATIONS: While our study is well powered to achieve the primary objectives, our sub-group analyses were under powered. CONCLUSIONS: In one of the very few longitudinal neuroimaging studies of young people at high risk for BD, this study reports novel evidence of atypical white matter development in HR individuals in a key cortico-limbic tract involved in emotion regulation. Our findings also suggest that this different white matter developmental trajectory may be stronger in HR individuals without affective psychopathology. As such, increases in FA in the right CGH of HR participants may be a biomarker of resilience to mood disorders.


Subject(s)
Bipolar Disorder , White Matter , Adolescent , Adult , Anisotropy , Bipolar Disorder/diagnostic imaging , Bipolar Disorder/genetics , Child , Diffusion Tensor Imaging/methods , Hippocampus/diagnostic imaging , Hippocampus/pathology , Humans , Nerve Net/pathology , White Matter/diagnostic imaging , White Matter/pathology , Young Adult
3.
Psychol Med ; 52(7): 1344-1355, 2022 05.
Article in English | MEDLINE | ID: mdl-32892764

ABSTRACT

BACKGROUND: Bipolar disorder (BD) is a familial psychiatric disorder associated with frontotemporal and subcortical brain abnormalities. It is unclear whether such abnormalities are present in relatives without BD, and little is known about structural brain trajectories in those at risk. METHOD: Neuroimaging was conducted at baseline and at 2-year follow-up interval in 90 high-risk individuals with a first-degree BD relative (HR), and 56 participants with no family history of mental illness who could have non-BD diagnoses. All 146 subjects were aged 12-30 years at baseline. We examined longitudinal change in gray and white matter volume, cortical thickness, and surface area in the frontotemporal cortex and subcortical regions. RESULTS: Compared to controls, HR participants showed accelerated cortical thinning and volume reduction in right lateralised frontal regions, including the inferior frontal gyrus, lateral orbitofrontal cortex, frontal pole and rostral middle frontal gyrus. Independent of time, the HR group had greater cortical thickness in the left caudal anterior cingulate cortex, larger volume in the right medial orbitofrontal cortex and greater area of right accumbens, compared to controls. This pattern was evident even in those without the new onset of psychopathology during the inter-scan interval. CONCLUSIONS: This study suggests that differences previously observed in BD are developing prior to the onset of the disorder. The pattern of pathological acceleration of cortical thinning is likely consistent with a disturbance of molecular mechanisms responsible for normal cortical thinning. We also demonstrate that neuroanatomical differences in HR individuals may be progressive in some regions and stable in others.


Subject(s)
Bipolar Disorder , Adolescent , Adult , Bipolar Disorder/diagnostic imaging , Bipolar Disorder/genetics , Bipolar Disorder/pathology , Brain/pathology , Cerebral Cortical Thinning , Child , Humans , Magnetic Resonance Imaging , Neuroimaging , Young Adult
4.
Article in English | MEDLINE | ID: mdl-20013442

ABSTRACT

Taints and off-flavours in foods are a major concern to the food industry. Identification of the compound(s) causing a taint or off-flavour in food and accurate quantification are critical in assessing the potential safety risks of a product or ingredient. Even when the tainting compound(s) are not at a level that would cause a safety concern, taints and off-flavours can have a significant impact on the quality and consumers' acceptability of products. The analysis of taints and off-flavour compounds presents an analytical challenge especially in an industrial laboratory environment because of the low levels, often complex matrices and potential for contamination from external laboratory sources. This review gives an outline of the origins of chemical taints and off-flavours and looks at the methods used for analysis and the merits and drawbacks of each technique. Extraction methods and instrumentation are covered along with possible future developments. Generic screening methods currently lack the sensitivity required to detect the low levels required for some tainting compounds and a more targeted approach is often required. This review highlights the need for a rapid but sensitive universal method of extraction for the unequivocal determination of tainting compounds in food.


Subject(s)
Flavoring Agents/analysis , Food Analysis
5.
Proc Natl Acad Sci U S A ; 106(52): 22341-5, 2009 Dec 29.
Article in English | MEDLINE | ID: mdl-20018706

ABSTRACT

A key consideration in assessing impacts of climate change is the possibility of synergistic effects with other human-induced stressors. In the ocean realm, climate change and overfishing pose two of the greatest challenges to the structure and functioning of marine ecosystems. In eastern Tasmania, temperate coastal waters are warming at approximately four times the global ocean warming average, representing the fastest rate of warming in the Southern Hemisphere. This has driven range extension of the ecologically important long-spined sea urchin (Centrostephanus rodgersii), which has now commenced catastrophic overgrazing of productive Tasmanian kelp beds leading to loss of biodiversity and important rocky reef ecosystem services. Coincident with the overgrazing is heavy fishing of reef-based predators including the spiny lobster Jasus edwardsii. By conducting experiments inside and outside Marine Protected Areas we show that fishing, by removing large predatory lobsters, has reduced the resilience of kelp beds against the climate-driven threat of the sea urchin and thus increased risk of catastrophic shift to widespread sea urchin barrens. This shows that interactions between multiple human-induced stressors can exacerbate nonlinear responses of ecosystems to climate change and limit the adaptive capacity of these systems. Management actions focused on reducing the risk of catastrophic phase shift in ecosystems are particularly urgent in the face of ongoing warming and unprecedented levels of predator removal from the world's oceans.


Subject(s)
Climate Change , Ecosystem , Fishes , Kelp , Animals , Biodiversity , Food Chain , Humans , Models, Biological , Palinuridae/physiology , Predatory Behavior , Sea Urchins/physiology , Tasmania
6.
FEMS Microbiol Ecol ; 50(3): 255-63, 2004 Nov 01.
Article in English | MEDLINE | ID: mdl-19712365

ABSTRACT

ABSTRACT The establishment and growth of trees can be compromised by soil contamination which can reduce populations of key microbial symbionts. We describe the colonisation of grey alder (Alnus incana) by Frankia from 10 urban soils with varying degrees of organic and inorganic pollution. Principal components analysis (PCA) of soil chemical profiles showed a separation of remediated and unremediated soils. A. incana seedlings were used as trap plants to capture the microsymbiont from soil. After 6 months growth, nodulation was lowest on trees grown with the most contaminated soils. Plant biomass was positively correlated with root nodule biomass and negatively correlated with PAH concentration. DNA was isolated from nodules for the analysis of Frankia genetic diversity. The polymerase chain reaction (PCR) was used to amplify the 16S-23S intergenic spacer (IGS) of Frankia ribosomal DNA. PCR products were subject to restriction digestion yielding 10 restriction fragment length polymorphism (RFLP) types from 72 nodules analysed. Our results demonstrate that each soil supports a distinct nodulating Frankia community. Partial 16S sequencing placed most strains in Frankia clusters 1a and 1b, which are typically Alnus-infecting, but sequences from several nodules obtained from a gasworks soil belonged to cluster 3, normally associated with Elaeagnus. These results show for the first time that polluted soils can be an effective source of Alnus-infective Frankia. Inoculation with site-adapted Frankia under greenhouse conditions could thus be an appropriate strategy to increase the symbiotic capacity of A. incana and to improve its chances of survival and growth when planted on polluted soils.


Subject(s)
Alnus/microbiology , Frankia/classification , Frankia/genetics , Genetic Variation , Plant Roots/microbiology , Soil/analysis , Alnus/drug effects , Alnus/growth & development , Biomass , Cluster Analysis , DNA Fingerprinting/methods , DNA, Bacterial/chemistry , DNA, Bacterial/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , DNA, Ribosomal Spacer/genetics , Inorganic Chemicals/analysis , Molecular Sequence Data , Organic Chemicals/analysis , Phylogeny , Plant Root Nodulation/drug effects , Polymorphism, Restriction Fragment Length , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA , Soil Pollutants/analysis
7.
Mol Ecol ; 12(11): 3085-95, 2003 Nov.
Article in English | MEDLINE | ID: mdl-14629388

ABSTRACT

Arbuscular mycorrhizal (AM) fungi are biotrophic symbionts colonizing the majority of land plants, and are of major importance in plant nutrient supply. Their diversity is suggested to be an important determinant of plant community structure, but the influence of host-plant and environmental factors on AM fungal community in plant roots is poorly documented. Using the terminal restriction fragment length polymorphism (T-RFLP) strategy, the diversity of AM fungi was assessed in 89 roots of three grass species (Agrostis capillaris, Festuca rubra, Poa pratensis) that co-occurred in the same plots of a field experiment. The impact of different soil amendments (nitrogen, lime, nitrogen and lime) and insecticide application on AM fungal community was also studied. The level of diversity found in AM fungal communities using the T-RFLP strategy was consistent with previous studies based on clone libraries. Our results clearly confirm that an AM fungal host-plant preference exists, even between different grass species. AM communities colonizing A. capillaris were statistically different from the others (P < 0.05). Although grass species evenness changed in amended soils, AM fungal community composition in roots of a given grass species remained stable. Conversely, in plots where insecticide was applied, we found higher AM fungal diversity and, in F. rubra roots, a statistically different AM fungal community.


Subject(s)
Genetic Variation/drug effects , Mycorrhizae/genetics , Soil , Symbiosis , Analysis of Variance , Calcium Compounds/pharmacology , Electrophoresis, Agar Gel , Genetic Variation/genetics , Insecticides/pharmacology , Mycorrhizae/physiology , Nitrogen/pharmacology , Oxides/pharmacology , Phylogeny , Poaceae/physiology , Polymorphism, Restriction Fragment Length , Population Dynamics , Principal Component Analysis , Scotland , Species Specificity
8.
Vet Clin North Am Equine Pract ; 15(1): 211-21, 1999 Apr.
Article in English | MEDLINE | ID: mdl-10218251

ABSTRACT

Concepts of acupuncture in traditional Chinese medicine are presented for clarity and contrast to Western medical concepts. Various acupuncture techniques and methods are discussed including dry needling, electroacupuncture, acupuncture using hypodermic needles, and injecting various solutions into the acupuncture sites. Potential complications and precautions are also presented. A type of chronic back pain is discussed that is possibly associated with a radiculopathically induced, hypersensitivity myofascial syndrome that presents as a fibromyalgia-like syndrome. Effective acupuncture treatment for the described chronic fibromyalgia-like syndrome is discussed.


Subject(s)
Acupuncture Therapy/veterinary , Back Pain/veterinary , Horse Diseases/therapy , Animals , Back Pain/therapy , Horses
9.
Vet Clin North Am Equine Pract ; 15(1): 263-80, x, 1999 Apr.
Article in English | MEDLINE | ID: mdl-10218254

ABSTRACT

This article introduces the importance of considering all related physical findings, evaluating the whole horse and determining the root cause in order to achieve the best treatment results, prevent recurrence, and return the patient to full function. The roles of shoeing, turnout, teeth, training aids and devices, compensatory lameness, working surface (footing), longing, ponying, hot walkers, and swimming are discussed in relationship to back dysfunction and rehabilitation. Postural analysis and measures for muscle and postural corrections are also presented. Ground and under saddle rehabilitative exercises are explained as to value, concept, and methodology. Rehabilitative modalities including stretching, massage, magnetic therapy, heat, and cold are explored as adjunctive therapy.


Subject(s)
Back Pain/veterinary , Horse Diseases/therapy , Spinal Injuries/veterinary , Animals , Back Pain/rehabilitation , Horses , Posture , Spinal Injuries/rehabilitation
10.
J Pharm Pharmacol ; 49(4): 377-83, 1997 Apr.
Article in English | MEDLINE | ID: mdl-9232534

ABSTRACT

A previously developed computer model, named Pore-Cor, has been used to simulate the changes in the void-space dimensions which occur during the compaction of tablets over a range of pressures. The tablets were made by mixing pharmaceutical grade crystalline lactose and an anti-inflammatory compound in the proportion 4:1. Compacts were made by placing a weighed amount of the mixed powder into a stainless-steel die and applying pressure with a hand-operated calibrated hydraulic press. Compacts were prepared at eight pressures over the hydraulic pressure range 1 to 8 ton in-2 (15.4-123.2 MPa) in 1 ton in-2 increments. Mercury-intrusion curves were measured for the eight samples by use of a porosimeter and the Pore-Cor package was then used to simulate the mercury-intrusion curves and generate void-space models of the correct porosity. The experimental and simulated characteristic throat diameter, the experimental and simulated porosity, and the simulated permeability of the tablets have all been shown to follow expected trends. The successful modelling of void-structure parameters, which are difficult or impossible to measure experimentally, opens the way to an improved understanding of the strength of compacts.


Subject(s)
Anti-Inflammatory Agents/chemistry , Computer Simulation , Lactose/chemistry , Models, Chemical , Tablets/standards , Biomechanical Phenomena , Calibration , Crystallization , Mercury , Particle Size , Permeability , Porosity , Pressure
11.
Gene ; 136(1-2): 13-25, 1993 Dec 22.
Article in English | MEDLINE | ID: mdl-8293996

ABSTRACT

The nucleotide sequence of a 14.4-kb region (tra) associated with DNA transfer of the staphylococcal conjugative plasmid, pSK41, has been determined. Analysis of the sequence revealed the presence of 15 genes potentially involved in the conjugative process. Polypeptide products likely to correspond to ten of these genes have been identified, of which one was found to be a lipoprotein. Comparison of the deduced tra products to the protein databases revealed several interesting similarities, one of which suggests an evolutionary link between this Gram+ bacterial conjugation system and DNA transfer systems of Gram- bacteria, such as Escherichia coli and Agrobacterium tumefaciens. The nt sequence also provided an insight into the transcriptional organisation and regulation of the region.


Subject(s)
Bacterial Proteins/genetics , Plasmids/genetics , Staphylococcus/genetics , Amino Acid Sequence , Base Sequence , Biological Evolution , Cloning, Molecular , Conjugation, Genetic/genetics , DNA, Bacterial , Lipoproteins/genetics , Molecular Sequence Data , Pheromones/genetics , Protein Sorting Signals/genetics , Sequence Homology, Amino Acid , Sequence Homology, Nucleic Acid , Transcription, Genetic
12.
Clin Chim Acta ; 158(1): 71-9, 1986 Jul 15.
Article in English | MEDLINE | ID: mdl-3742817

ABSTRACT

Delipidation of liver homogenates, using an organic solvent system which does not denature proteins, increases measurable ferritin by 25-33%, compared to ferritin concentrations by standard heat supernatant assays. When applied to polyacrylamide gradient gels, lipid-associated ferritin does not enter the gel but after delipidation, this ferritin co-migrates with cytosolic ferritin and with purified liver ferritin. The biological significance of the association of ferritin with lipid has yet to be examined.


Subject(s)
Ferritins/analysis , Lipids/analysis , Liver/analysis , Animals , Electrophoresis, Polyacrylamide Gel , Ferritins/isolation & purification , Guinea Pigs , Hot Temperature , Humans , Male , Rats
13.
Anal Biochem ; 151(2): 561-5, 1985 Dec.
Article in English | MEDLINE | ID: mdl-4096386

ABSTRACT

A simple, rapid technique for purification of ferritin from human liver tissue is described. Methanol, at a final concentration of 40% (v/v) in liver homogenate, precipitates the majority of proteins but does not affect ferritin. Subsequent heating of this homogenate at 75 degrees C for 10 min results in a purified ferritin preparation as judged by immunoelectrophoresis and polyacrylamide gel electrophoresis. The resultant purified ferritin contained the same amount of iron as the original endogenous ferritin. There were no significant differences (paired t tests) in the amount of protein in the purified ferritin preparation when measured by rocket immunoelectrophoresis and by the Lowry procedure, suggesting that the antigenecity of ferritin was unaffected by the methanol and heat treatment. Both endogenous liver ferritin and radiolabeled human liver ferritin added to liver homogenates were recovered after methanol and heat treatment with similar yields (77 +/- 7% and 70 +/- 2%, respectively) when compared with the standard treatment of heating a homogenate at 75 degrees C. The overall ferritin yield with this rapid procedure was 40%.


Subject(s)
Ferritins/isolation & purification , Chromatography, High Pressure Liquid/methods , Electrophoresis, Agar Gel , Electrophoresis, Polyacrylamide Gel , Hot Temperature , Humans , Immunoelectrophoresis , Iodine Radioisotopes , Liver/analysis , Methanol
14.
15.
J Pharm Pharmacol ; 35(6): 341-4, 1983 Jun.
Article in English | MEDLINE | ID: mdl-6135770

ABSTRACT

When submitted to X-ray crystallography, two enteric coating polymers, cellulose acetate phthalate and polyvinyl acetate phthalate, were found to be essentially amorphous in structure. Values for the glass transition temperature, Tg, of each polymer have been obtained using both a surface microindentation technique and differential scanning calorimetry. The effect on this parameter of an increasing concentration of a plasticizer, diethyl phthalate, has also been determined. Measured values for Tg have been compared with predicted values obtained using a suitable mixture-rule model: the surface microindentation technique values were closer to the predicted.


Subject(s)
Polymers , Tablets, Enteric-Coated , Cellulose/analogs & derivatives , Chemistry, Pharmaceutical , Hardness , Phthalic Acids , Polyvinyls , Thermodynamics , X-Ray Diffraction
16.
J Pharm Pharmacol ; 34(1): 5-8, 1982 Jan.
Article in English | MEDLINE | ID: mdl-6121034

ABSTRACT

The effect of an increasing concentration of plasticizer and pigment on the permeability to both water vapour and simulated gastric juice of cellulose acetate phthalate and polyvinyl acetate phthalate has been evaluated. There were significant differences between the permeability coefficients of each polymer, particularly with regard to water vapour. The presence of additives within the film coatings had a greater effect on the properties of cellulose acetate phthalate than those of polyvinyl acetate phthalate. Suitable formulations of each polymer were used to enteric coat 325 mg aspirin tablets, which were subsequently subjected to both the Disintegration Test for Enteric Coated Tablets B.P. and a dissolution procedure to monitor the release of drug in simulated gastric juice and simulated intestinal fluid. Both polymers demonstrated their suitability for producing enteric coatings. However, polyvinyl acetate phthalate yielded a faster release of aspirin in simulated intestinal fluid than did cellulose acetate phthalate.


Subject(s)
Tablets, Enteric-Coated , Cellulose/analogs & derivatives , Drug Stability , Permeability , Plasticizers , Solubility , Water
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