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1.
Perspect Public Health ; : 17579139231205488, 2023 Oct 18.
Article in English | MEDLINE | ID: mdl-37850725

ABSTRACT

AIMS: There is a need for interventions that meet the needs of low socioeconomic status (SES) groups, to encourage the adoption of healthy diets and physical activity, in line with current public health guidance. This qualitative research used co-production, a method which actively involves the relevant community, to identify and describe public health interventions to support a group of mothers of young children living in a low SES area. METHODS: A group of 20 mothers took part in three in-depth qualitative interviews to discuss in detail the type of support that would be of value to them for the adoption and maintenance of healthy behaviours. The mothers were subsequently invited to take part in a public engagement project, a community-based self-help group. RESULTS: Four themes explained the principles of interventions that would be of value in supporting the mothers with the adoption of healthy behaviours, namely, a community-based self-help group, support for the whole family and support in the home and influencing the environment. These were then further developed into two types of intervention (1) learning for self-help and family care, which encompassed the first three learning-based themes and (2) community of support, which covered influencing the environment and the experience of the community-based self-help group. CONCLUSION: Co-production enabled a group of mothers of young children, from a low SES area, to describe the type of support that would help them with the establishment and maintenance of healthy lifestyle behaviours. A community-based self-help group warrants further research.

2.
BMJ Mil Health ; 2023 Jul 02.
Article in English | MEDLINE | ID: mdl-37400128

ABSTRACT

Advances in technology have improved the ability for real-time communication and enhanced awareness of medically related information on the battlefield. A government off-the-shelf platform, Team Awareness Kit (TAK), may enhance the ability for battlefield healthcare delivery, evacuation, telecommunication, and medical command and control. Integration of TAK into existing medical infrastructure provides a global view of resources, patient movement and direct communication, significantly reducing the 'fog of war' as it relates to battlefield injury and evacuation. Rapid integration and adoption are technically feasible with minimal resource investment. This technology can be rapidly scaled for the increasingly interconnected world of healthcare delivery.

3.
BMC Public Health ; 22(1): 1092, 2022 06 01.
Article in English | MEDLINE | ID: mdl-35650565

ABSTRACT

BACKGROUND: Public health guidance and associated interventions seek to bring about change in diet and physical activity behaviours to improve life expectancy and healthy life expectancy in the population. Low socioeconomic status (SES) groups suffer from reduced life/healthy life expectancy compared with the population as a whole. This in-depth qualitative study, investigates the lives and experiences of mothers with young children living in a low SES area in a London (UK) borough, to understand the context in which current public health guidance on diet and physical activity is received and viewed, and how this understanding could be used to inform the development of public health guidance and interventions for this group. METHODS: The mothers (n = 20), were recruited from a Surestart Centre, Children's Centres and through the local branch of a national charity. The mothers took part in a series of three in depth interviews over two years (2016-2017). Thematic analysis was used to generate an iterative set of codes informing an understanding of motherhood, diet and physical activity. RESULTS: Motherhood was found to be a major factor for understanding and interpreting how women in low SES areas respond to public health guidance on diet and physical activity. The mothers were well informed about dietary guidance, considered that provision of healthy food was critical to the mothering role, but found it difficult to implement the guidance in their own lives. In contrast, physical activity was not seen as integral to the mothering role, although it was acknowledged that it played a part in ensuring that the mothers remained healthy enough to fulfil all their duties. Constrained by the ethic of care, and a lack of material and time resources, the mothers prioritised their family's health above their own. This study, enabled the mothers to articulate ideas for interventions that would be supportive of a healthy lifestyle and of practical application in their busy lives. CONCLUSIONS: Mothers from this low SES area responded differently to the public health guidance on diet and on physical activity. Whilst providing and modelling a healthy diet was seen as an essential part of the mother's role, participating in leisure based physical activity was problematic, and unless carefully framed, could be perceived as selfish behaviour, inappropriate for the "good" mother.


Subject(s)
Diet , Public Health , Child , Child, Preschool , Exercise , Female , Healthy Lifestyle , Humans , Mothers
4.
Harmful Algae ; 99: 101919, 2020 11.
Article in English | MEDLINE | ID: mdl-33218444

ABSTRACT

The productive but highly exposed coastline of the southern Benguela eastern boundary upwelling system offers limited natural environment for aquaculture. Saldanha Bay located on the west coast of South Africa is one of the few embayments on the coastline that provides a productive and relatively sheltered environment suitable for the cultivation of shellfish. Consequently, bivalve culture in South Africa is centered in Saldanha Bay and is presently targeted for expansion. Pseudo-nitzschia blooms including toxin-producing species are shown to contribute significantly to the phytoplankton of Saldanha Bay specifically in spring and summer. Their dominance at this time of the year, when upwelling is strongest, fits the ecological profile of Pseudo-nitzschia occurring during periods of high turbulence and nutrients. Multiple Pseudo-nitzschia blooms were sampled under varying environmental conditions and the strength of the relationship between Pseudo-nitzschia cell abundance and particulate domoic acid (pDA) content, reflecting bloom toxicity, varied greatly. This variability is the result of the combined influence of species and strain composition of the Pseudo-nitzschia assemblage and the effect of environmental conditions on toxin production. Elevated levels of pDA were associated with higher concentrations of cells of the P. seriata complex differentiated by frustule width (>3 µm). P. australis was identified as a toxin-producing species and a prominent member of the P. seriata complex. Low DA levels in shellfish in Saldanha Bay are considered a function of low cellular domoic acid (cDA). Silicate limitation has emerged as an important factor inducing DA production in Pseudo-nitzschia species. The high ratio of silicate to nitrate in Saldanha Bay provides a plausible explanation for the low toxin content of Pseudo-nitzschia blooms in the bay and the consequent low risk posed by these blooms to the aquaculture sector.


Subject(s)
Bivalvia , Diatoms , Animals , Aquaculture , Phytoplankton , Shellfish
5.
Sci Rep ; 7(1): 13788, 2017 10 23.
Article in English | MEDLINE | ID: mdl-29062098

ABSTRACT

Cu(In,Ga)Se2 (CIGS) is presently the most efficient thin-film photovoltaic technology with efficiencies exceeding 22%. An important factor impacting the efficiency is metastability, where material changes occur over timescales of up to weeks during light exposure. A previously proposed (V Se -V Cu ) divacancy model presents a widely accepted explanation. We present experimental evidence for the optically induced metastability transition and expand the divacancy model with first-principles calculations. Using photoluminescence excitation spectroscopy, we identify a sub-bandgap optical transition that severely deteriorates the carrier lifetime. This is in accordance with the expanded divacancy model, which predicts that states below the conduction band are responsible for the metastability change. We determine the density-capture cross-section product of the induced lifetime-limiting states and evaluate their impact on device performance. The experimental and theoretical findings presented can allow assessment of metastability characteristics of leading thin-film photovoltaic technologies.

6.
J Autoimmun ; 77: 11-38, 2017 02.
Article in English | MEDLINE | ID: mdl-27939129

ABSTRACT

Campylobacter jejuni is a leading cause of bacterial gastroenteritis linked to several serious autoimmune sequelae such as the peripheral neuropathies Guillain Barré syndrome (GBS) and Miller Fisher syndrome (MFS). We hypothesized that GBS and MFS can result in NOD wild type (WT) mice or their congenic interleukin (IL)-10 or B7-2 knockouts secondary to C. jejuni infection. Mice were gavaged orally with C. jejuni strains HB93-13 and 260.94 from patients with GBS or CF93-6 from a patient with MFS and assessed for clinical neurological signs and phenotypes, anti-ganglioside antibodies, and cellular infiltrates and lesions in gut and peripheral nerve tissues. Significant increases in autoantibodies against single gangliosides (GM1, GQ1b, GD1a) occurred in infected NOD mice of all genotypes, although the isotypes varied (NOD WT had IgG1, IgG3; NOD B7-2-/- had IgG3; NOD IL-10-/- had IgG1, IgG3, IgG2a). Infected NOD WT and NOD IL-10-/- mice also produced anti-ganglioside antibodies of the IgG1 isotype directed against a mixture of GM1/GQ1b gangliosides. Phenotypic tests showed significant differences between treatment groups of all mouse genotypes. Peripheral nerve lesions with macrophage infiltrates were significantly increased in infected mice of NOD WT and IL-10-/- genotypes compared to sham-inoculated controls, while lesions with T cell infiltrates were significantly increased in infected mice of the NOD B7-2-/- genotype compared to sham-inoculated controls. In both infected and sham inoculated NOD IL-10-/- mice, antibiotic treatment exacerbated neurological signs, lesions and the amount and number of different isotypes of antiganglioside autoantibodies produced. Thus, inducible mouse models of post-C. jejuni GBS are feasible and can be characterized based on evaluation of three factors-onset of GBS clinical signs/phenotypes, anti-ganglioside autoantibodies and nerve lesions. Based on these factors we characterized 1) NOD B-7-/- mice as an acute inflammatory demyelinating polyneuropathy (AIDP)-like model, 2) NOD IL-10-/- mice as an acute motor axonal neuropathy (AMAN)-like model best employed over a limited time frame, and 3) NOD WT mice as an AMAN model with mild clinical signs and lesions. Taken together these data demonstrate that C. jejuni strain genotype, host genotype and antibiotic treatment affect GBS disease outcomes in mice and that many disease phenotypes are possible.


Subject(s)
Anti-Bacterial Agents/adverse effects , Campylobacter Infections/complications , Campylobacter Infections/microbiology , Campylobacter jejuni , Guillain-Barre Syndrome/etiology , Guillain-Barre Syndrome/pathology , Animals , Anti-Bacterial Agents/pharmacology , Antibodies, Bacterial/immunology , Autoantibodies/immunology , Campylobacter Infections/drug therapy , Cytokines/blood , Cytokines/metabolism , Disease Models, Animal , Disease Progression , Ganglia, Spinal/immunology , Ganglia, Spinal/metabolism , Ganglia, Spinal/pathology , Guillain-Barre Syndrome/physiopathology , Immunoglobulin G/immunology , Mice , Mice, Inbred NOD , Mice, Knockout , Peripheral Nerves/metabolism , Peripheral Nerves/pathology , Peripheral Nerves/physiopathology , Peripheral Nerves/virology , Phenotype , T-Lymphocyte Subsets/immunology , T-Lymphocyte Subsets/metabolism
7.
Rev Sci Instrum ; 86(1): 013907, 2015 Jan.
Article in English | MEDLINE | ID: mdl-25638097

ABSTRACT

Fiber-fed time-resolved photoluminescence is demonstrated as a tool for immediate process feedback after deposition of the absorber layer for CuInxGa(1-x)Se2 and Cu2ZnSnSe4 photovoltaic devices. The technique uses a simplified configuration compared to typical laboratory time-resolved photoluminescence in the delivery of the exciting beam, signal collection, and electronic components. Correlation of instrument output with completed device efficiency is demonstrated over a large sample set. The extraction of the instrument figure of merit, depending on both the initial luminescence intensity and its time decay, is explained and justified. Limitations in the prediction of device efficiency by this method, including surface effect, are demonstrated and discussed.

8.
Mucosal Immunol ; 7(4): 802-17, 2014 Jul.
Article in English | MEDLINE | ID: mdl-24220299

ABSTRACT

Campylobacter jejuni is a leading cause of foodborne enteritis that has been linked to the autoimmune neuropathy, Guillain Barré syndrome (GBS). C57BL/6 interleukin (IL)-10(+/+) and congenic IL-10(-/-) mice serve as C. jejuni colonization and colitis models, respectively, but a mouse model for GBS is lacking. We demonstrate that IL-10(-/-) mice infected with a C. jejuni colitogenic human isolate had significantly upregulated type 1 and 17 but not type 2 cytokines in the colon coincident with infiltration of phagocytes, T cells and innate lymphoid cells (ILCs). Both ILC and T cells participated in interferon-γ (IFN-γ), IL-17, and IL-22 upregulation but in a time- and organ-specific manner. T cells were, however, necessary for colitis as mice depleted of Thy-1(+) cells were protected while neither Rag1(-/-) nor IL-10R blocked Rag1(-/-) mice developed colitis after infection. Depleting IFN-γ, IL-17, or both significantly ameliorated colitis and drove colonic responses toward type 2 cytokine and antibody induction. In contrast, C. jejuni GBS patient strains induced mild colitis associated with blunted type 1/17 but enhanced type 2 responses. Moreover, the type 2 but not type 1/17 antibodies cross-reacted with peripheral nerve gangliosides demonstrating autoimmunity.


Subject(s)
Autoimmunity , Campylobacter Infections/immunology , Campylobacter jejuni/immunology , Colitis/immunology , Animals , Antibodies, Bacterial/immunology , Autoimmunity/genetics , Campylobacter Infections/genetics , Campylobacter Infections/metabolism , Campylobacter Infections/microbiology , Colitis/genetics , Colitis/microbiology , Cytokines/metabolism , Disease Models, Animal , Immunity, Cellular , Immunity, Innate , Immunoglobulin Class Switching , Immunoglobulin G , Interleukin-10/deficiency , Interleukin-10/genetics , Mice , Mice, Knockout , Severity of Illness Index , T-Lymphocyte Subsets/immunology , T-Lymphocyte Subsets/metabolism
9.
Microb Pathog ; 54: 1-19, 2013 Jan.
Article in English | MEDLINE | ID: mdl-22960579

ABSTRACT

Human Campylobacter jejuni infection can result in an asymptomatic carrier state, watery or bloody diarrhea, bacteremia, meningitis, or autoimmune neurological sequelae. Infection outcomes of C57BL/6 IL-10(-/-) mice orally infected with twenty-two phylogenetically diverse C. jejuni strains were evaluated to correlate colonization and disease phenotypes with genetic composition of the strains. Variation between strains was observed in colonization, timing of development of clinical signs, and occurrence of enteric lesions. Five pathotypes of C. jejuni in C57BL/6 IL-10(-/-) mice were delineated: little or no colonization, colonization without disease, colonization with enteritis, colonization with hemorrhagic enteritis, and colonization with neurological signs with or without enteritis. Virulence gene content of ten sequenced strains was compared in silico; virulence gene content of twelve additional strains was compared using a C. jejuni pan-genome microarray. Neither total nor virulence gene content predicted pathotype; nor was pathotype correlated with multilocus sequence type. Each strain was unique with regard to absences of known virulence-related loci and/or possession of point mutations and indels, including phase variation, in virulence-related genes. An experiment in C. jejuni 11168-infected germ-free mice showed that expression levels of ninety open reading frames (ORFs) were significantly up- or down-regulated in the mouse cecum at least two-fold compared to in vitro growth. Genomic content of these ninety C. jejuni 11168 ORFs was significantly correlated with the capacity to colonize and cause enteritis in C57BL/6 IL-10(-/-) mice. Differences in gene expression levels and patterns are thus an important determinant of pathotype in C. jejuni strains in this mouse model.


Subject(s)
Campylobacter Infections/immunology , Campylobacter Infections/pathology , Campylobacter jejuni/immunology , Campylobacter jejuni/pathogenicity , Interleukin-10/deficiency , Open Reading Frames , Virulence Factors/genetics , Animals , Campylobacter Infections/microbiology , Campylobacter jejuni/classification , Campylobacter jejuni/genetics , Female , Gene Expression , Genotype , Interleukin-10/genetics , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , Multilocus Sequence Typing , Virulence , Virulence Factors/metabolism
10.
Rev Sci Instrum ; 83(8): 083702, 2012 Aug.
Article in English | MEDLINE | ID: mdl-22938298

ABSTRACT

We present a near-field scanning microwave microscope (NSMM) that has been configured for imaging photovoltaic samples. Our system incorporates a Pt-Ir tip inserted into an open-ended coaxial cable to form a weakly coupled resonator, allowing the microwave reflection S(11) signal to be measured across a sample over a frequency range of 1 GHz - 5 GHz. A phase-tuning circuit increased impedance-measurement sensitivity by allowing for tuning of the S(11) minimum down to -78 dBm. A bias-T and preamplifier enabled simultaneous, non-contact measurement of the DC tip-sample current, and a tuning fork feedback system provided simultaneous topographic data. Light-free tuning fork feedback provided characterization of photovoltaic samples both in the dark and under illumination at 405 nm. NSMM measurements were obtained on an inhomogeneous, third-generation Cu(In,Ga)Se(2) (CIGS) sample. The S(11) and DC current features were found to spatially broaden around grain boundaries with the sample under illumination. The broadening is attributed to optically generated charge that becomes trapped and changes the local depletion of the grain boundaries, thereby modifying the local capacitance. Imaging provided by the NSMM offers a new RF methodology to resolve and characterize nanoscale electrical features in photovoltaic materials and devices.

11.
Br J Radiol ; 84(1002): 570-5, 2011 Jun.
Article in English | MEDLINE | ID: mdl-21343323

ABSTRACT

Extracranial epidural emphysema is an uncommon phenomenon that refers to the presence of gas within the epidural space. As an isolated finding, it is typically benign, but it can be a secondary sign of more ominous disease processes, such as pneumothorax, pneumoperitoneum and epidural abscess. Although the phenomenon has been cited in case reports, a comprehensive review of this topic is lacking in the radiology literature. The authors' aim is to report our experience with extracranial epidural emphysema, illustrating the spectrum of its clinical presentation. We also review the aetiology, pathophysiology, diagnosis and management of extracranial epidural emphysema.


Subject(s)
Emphysema/diagnosis , Epidural Space , Spinal Diseases/diagnosis , Aged, 80 and over , Emphysema/etiology , Emphysema/therapy , Epidural Space/diagnostic imaging , Female , Humans , Magnetic Resonance Imaging/methods , Male , Middle Aged , Spinal Diseases/etiology , Spinal Diseases/therapy , Tomography, X-Ray Computed/methods , Young Adult
12.
Oncogene ; 30(20): 2356-66, 2011 May 19.
Article in English | MEDLINE | ID: mdl-21242976

ABSTRACT

Cellular senescence is a programme of irreversible cell cycle arrest that normal cells undergo in response to progressive shortening of telomeres, changes in telomeric structure, oncogene activation or oxidative stress. The underlying signalling pathways, of major clinicopathological relevance, are unknown. We combined genome-wide expression profiling with genetic complementation to identify genes that are differentially expressed when conditionally immortalised human fibroblasts undergo senescence upon activation of the p16-pRB and p53-p21 tumour suppressor pathways. This identified 816 up and 961 downregulated genes whose expression was reversed when senescence was bypassed. Overlay of this data set with the meta-signatures of genes upregulated in cancer showed that nearly 50% of them were downregulated upon senescence showing that even though overcoming senescence may only be one of the events required for malignant transformation, nearly half of the genes upregulated in cancer are related to it. Moreover 65 of the up and 26 of the downregulated genes are known downstream targets of nuclear factor (NF)-κB suggesting that senescence was associated with activation of the NF-κB pathway. Direct perturbation of this pathway bypasses growth arrest indicating that activation of NF-κB signalling has a causal role in promoting senescence.


Subject(s)
Cellular Senescence , NF-kappa B/metabolism , Cell Line, Transformed , Fibroblasts , Forkhead Box Protein M1 , Forkhead Transcription Factors , Gene Expression Profiling , Gene Expression Regulation , Genes, p16 , Genes, p53 , Genetic Complementation Test , Humans , Signal Transduction
14.
Microb Pathog ; 47(1): 38-46, 2009 Jul.
Article in English | MEDLINE | ID: mdl-19409975

ABSTRACT

Campylobacter jejuni, a leading cause of bacterial gastroenteritis, has a diverse spectrum of disease expression. Polymicrobial infections may contribute to this, such as Trichuris, which elicits type 2 cytokines (including IL-4) and downregulates type 1 immunity. In previous studies, gnotobiotic piglets infected with C. jejuni and Trichuris suis had bloody diarrhea and marked gastrointestinal pathology, including bacterial invasion into epithelial cells and macrophages. Neonatal swine given these dual infections had elevated IL-4 and IL-10 responses in feces. In the studies reported here, we hypothesized that IL-4 or IL-10 enhances invasion of intestinal pig epithelial cells (IPEC-1) by C. jejuni. 10-14-day-old IPEC-1 cells were pretreated with recombinant IL-4 (rIL-4) or rIL-10 for 5h and then challenged with C. jejuni. Cells pretreated with rIL-4 were viable and showed approximately 6-fold increases in C. jejuni (but not Escherichia coli DH5alpha) internalization compared to cells with no pretreatment. Enhanced C. jejuni invasion was rIL-4 dose-dependent and reversed by addition of anti-IL-4 antibody. Preincubation with rIL-10 did not significantly alter C. jejuni internalization. Transepithelial electrical resistance (TEER) was significantly reduced following rIL-4 treatment, but not rIL-10 treatment. After rIL-4 pretreatment and C. jejuni challenge, light microscopy showed vacuolated cells with damaged paracellular junctions. Transmission electron microscopy (TEM) showed multiple internalized bacteria. Most were in the cytoplasm, but some were within or adjacent to vacuoles. We conclude that rIL-4 damages paracellular junctions and alters the physiology of these epithelial cells allowing increased invasion of C. jejuni.


Subject(s)
Campylobacter jejuni/immunology , Campylobacter jejuni/pathogenicity , Epithelial Cells/microbiology , Interleukin-4/immunology , Animals , Cell Membrane/ultrastructure , Cells, Cultured , Cytoplasm/microbiology , Cytoplasm/ultrastructure , Epithelial Cells/ultrastructure , Escherichia coli/immunology , Escherichia coli/pathogenicity , Interleukin-10/immunology , Intestinal Mucosa/cytology , Microscopy , Microscopy, Electron, Transmission , Recombinant Proteins/immunology , Swine
15.
Microb Pathog ; 45(4): 241-57, 2008 Oct.
Article in English | MEDLINE | ID: mdl-18586081

ABSTRACT

We hypothesized that particular genetic backgrounds enhance rates of colonization, increase severity of enteritis, and allow for extraintestinal spread when inbred IL-10(-/-) mice are infected with pathogenic C. jejuni. Campylobacter jejuni stably colonized C57BL/6 and NOD mice, while congenic strains lacking IL-10 developed typhlocolitis following colonization that mimicked human campylobacteriosis. However, IL-10 deficiency alone was not necessary for the presence of C. jejuni in extraintestinal sites. C3H/HeJ tlr4(-/-) mice that specifically express the Cdcs1 allele showed colonization and limited extraintestinal spread without enteritis implicating this interval in the clinical presentation of C. jejuni infection. Furthermore, when the IL-10 gene is inactivated as in C3Bir tlr4(-/-) IL-10(-/-) mice, enteritis and intensive extraintestinal spread were observed, suggesting that clinical presentations of C. jejuni infection are controlled by a complex interplay of factors. These data demonstrate that lack of IL-10 had a greater effect on C. jejuni induced colitis than other immune elements such as TLR4 (C3H/HeJ, C3Bir IL-10(-/-)), MHC H-2g7, diabetogenic genes, and CTLA-4 (NOD) and that host genetic background is in part responsible for disease phenotype. C3Bir IL-10(-/-) mice where Cdcs1 impairs gut barrier function provide a new murine model of C. jejuni and can serve as surrogates for immunocompromised patients with extraintestinal spread.


Subject(s)
Campylobacter Infections/genetics , Campylobacter jejuni/physiology , Enteritis/microbiology , Host-Pathogen Interactions , Interleukin-10/immunology , Animals , Antibodies, Bacterial/blood , Campylobacter Infections/immunology , Campylobacter Infections/microbiology , Campylobacter Infections/pathology , Campylobacter jejuni/immunology , Campylobacter jejuni/pathogenicity , Enteritis/genetics , Enteritis/immunology , Enteritis/pathology , Humans , Interleukin-10/genetics , Mice , Mice, Inbred Strains , Mice, Knockout , Phenotype
16.
Vet Parasitol ; 153(1-2): 24-43, 2008 May 06.
Article in English | MEDLINE | ID: mdl-18342449

ABSTRACT

We tested the hypothesis that brown-headed cowbirds (Molothrus ater) harbor Sarcocystis neurona, the agent of equine protozoal myeloencephalitis (EPM), and act as intermediate hosts for this parasite. In summer 1999, wild caught brown-headed cowbirds were collected and necropsied to determine infection rate with Sarcocystis spp. by macroscopic inspection. Seven of 381 (1.8%) birds had grossly visible sarcocysts in leg muscles with none in breast muscles. Histopathology revealed two classes of sarcocysts in leg muscles, thin-walled and thick-walled suggesting two species. Electron microscopy showed that thick-walled cysts had characteristics of S. falcatula and thin-walled cysts had characteristics of S. neurona. Thereafter, several experiments were conducted to confirm that cowbirds had viable S. neurona that could be transmitted to an intermediate host and cause disease. Specific-pathogen-free opossums fed cowbird leg muscle that was enriched for muscle either with or without visible sarcocysts all shed high numbers of sporocysts by 4 weeks after infection, while the control opossum fed cowbird breast muscle was negative. These sporocysts were apparently of two size classes, 11.4+/-0.7 microm by 7.6+/-0.4 microm (n=25) and 12.6+/-0.6 microm by 8.0+/-0 microm (n=25). When these sporocysts were excysted and introduced into equine dermal cell tissue culture, schizogony occurred, most merozoites survived and replicated long term and merozoites sampled from the cultures with long-term growth were indistinguishable from known S. neurona isolates. A cowbird Sarcocystis isolate, Michigan Cowbird 1 (MICB1), derived from thin-walled sarcocysts from cowbirds that was passaged in SPF opossums and tissue culture went on to produce neurological disease in IFNgamma knockout mice indistinguishable from that of the positive control inoculated with S. neurona. This, together with the knowledge that S. falcatula does not cause lesions in IFNgamma knockout mice, showed that cowbird leg muscles had a Sarcocystis that fulfills the first aim of Koch's postulates to produce disease similar to S. neurona. Two molecular assays provided further support that both S. neurona and S. falcatula were present in cowbird leg muscles. In a blinded study, PCR-RFLP of RAPD-derived DNA designed to discriminate between S. neurona and S. falcatula showed that fresh sporocysts from the opossum feeding trial had both Sarcocystis species. Visible, thick-walled sarcocysts from cowbird leg muscle were positive for S. falcatula but not S. neurona; thin-walled sarcocysts typed as S. neurona. In 1999, DNA was extracted from leg muscles of 100 wild caught cowbirds and subjected to a PCR targeting an S. neurona specific sequence of the small subunit ribosomal RNA (SSU rRNA) gene. In control spiking experiments, this assay detected DNA from 10 S. neurona merozoites in 0.5g of muscle. In the 1999 experiment, 23 of 79 (29.1%) individual cowbird leg muscle samples were positive by this S. neurona-specific PCR. Finally, in June of 2000, 265 cowbird leg muscle samples were tested by histopathology for the presence of thick- and thin-walled sarcocysts. Seven percent (18/265) had only thick-walled sarcocysts, 0.8% (2/265) had only thin-walled sarcocysts and 1.9% (5/265) had both. The other half of these leg muscles when tested by PCR-RFLP of RAPD-derived DNA and SSU rRNA PCR showed a good correlation with histopathological results and the two molecular typing methods concurred; 9.8% (26/265) of cowbirds had sarcocysts in muscle, 7.9% (21/265) had S. falcatula sarcocysts, 1.1% (3/265) had S. neurona sarcocysts, and 0.8% (2/265) had both. These results show that some cowbirds have S. neurona as well as S. falcatula in their leg muscles and can act as intermediate hosts for both parasites.


Subject(s)
Bird Diseases/parasitology , Sarcocystis/isolation & purification , Sarcocystosis/veterinary , Songbirds/parasitology , Animals , Horses , Host-Parasite Interactions , Interferon-gamma/genetics , Interferon-gamma/metabolism , Mice , Mice, Knockout , Muscle, Skeletal/parasitology , Opossums/parasitology , Phylogeny , Polymerase Chain Reaction/veterinary , Polymorphism, Restriction Fragment Length , Sarcocystis/genetics , Sarcocystosis/parasitology , Sensitivity and Specificity , Skin/cytology , Skin/parasitology , Specific Pathogen-Free Organisms
17.
Anim Reprod Sci ; 108(3-4): 298-308, 2008 Nov.
Article in English | MEDLINE | ID: mdl-18065170

ABSTRACT

The effects of sperm freezing concentration (40 x 10(6)mL(-1) vs. 400 x 10(6)mL(-1)), straw size (0.25 mL vs. 0.5 mL) and freezing method (liquid nitrogen vapour in a Styrofoam box vs. programmable freezing machine) were evaluated in a 2 x 2 x 2 factorial experimental design using 3 split ejaculates from each of 4 stallions. Immediately after thawing, the total motility and forward progressive motility of spermatozoa frozen at a concentration of 40 x 10(6)mL(-1) was higher than for spermatozoa frozen at 400 x 10(6)mL(-1). No significant differences were observed in the semen parameters assessed after cryopreservation in either 0.25 or 0.5 mL straws. However, the programmable freezer provided a more consistent and reliable freezing rate than liquid nitrogen vapour. We conclude that an effective protocol for the cryopreservation of stallion spermatozoa at low concentrations would include concentrations of 40 x 10(6)mL(-1) in 0.25 mL straws using a programmable freezer. This freezing protocol would be suitable for emerging sperm technologies such as sex-preselection of stallion spermatozoa as the sorting process yields only low numbers of spermatozoa in a small volume available for either immediate insemination or cryopreservation.


Subject(s)
Cryopreservation/veterinary , Cryoprotective Agents/pharmacology , Horses/physiology , Semen Preservation/veterinary , Spermatozoa/physiology , Acrosome/physiology , Animals , Cryopreservation/methods , Linear Models , Male , Microscopy, Fluorescence , Microscopy, Phase-Contrast/veterinary , Random Allocation , Semen Preservation/methods , Sperm Motility/physiology , Spermatozoa/ultrastructure
18.
Anticancer Res ; 27(4B): 2265-8, 2007.
Article in English | MEDLINE | ID: mdl-17695512

ABSTRACT

BACKGROUND: Telomerase activity has been significantly associated with nodal metastasis and cellular proliferation in human breast cancer, indicating that its degree of expression has some form of vital control over the invasive nature of the malignancy concerned. Of the telomerase subunits, the reverse transcriptase (hTERT) is the main determinant of enzyme activity. Vascular endothelial growth factors (VEGF)-C and (VEGF)-D, matrix metalloprotease type 1 (MMP-1) and protease-activated receptors (PARs) have all been linked to promotion of tumour invasiveness and metastatic dissemination. This study aims to examine the association between hTERT transcription and that of VEGF-D, VEGF-C, MMP-1, PAR1a and PAR1b through a correlative analysis of the mRNA transcripts of these genes in human breast cancer. MATERIALS AND METHODS: Breast cancer tissues (n = 116) and normal tissues (n-31) were collected immediately after surgery and stored at -80 degrees C until use. The level of hTERT transcripts from the prepared DNA from the above samples was determined using real time-quantitative PCR based on the Amplifluor technology. The levels of the transcript were generated from a standard that was simultaneously amplified with the samples. Normalisation against cytokeratin 19 (CK19) and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) was also carried out. RESULTS: There was a positive correlation between hTERT mRNA expression (after CK19 normalisation) with both VEGF-D and MMP-1 in human breast cancer. PAR1 was seen to correlate with hTERT (after GAPDH normalisation) with a highly significant correlation with PAR1a alone. However there was no correlation between hTERT transcription and VEGF-C or with PAR1b alone. CONCLUSION: Our findings suggest that hTERT is a potential up-regulator of MMP-1, PAR1 and VEGF-D expression and this may explain its apparent control over the invasiveness and metastasis of the malignancy concerned.


Subject(s)
Breast Neoplasms/metabolism , Matrix Metalloproteinase 1/biosynthesis , RNA, Messenger/biosynthesis , Telomerase/biosynthesis , Vascular Endothelial Growth Factor C/biosynthesis , Vascular Endothelial Growth Factor D/biosynthesis , Breast Neoplasms/genetics , Breast Neoplasms/pathology , Humans , Neoplasm Staging , RNA, Messenger/genetics , Receptor, PAR-1/biosynthesis , Receptor, PAR-1/genetics , Reverse Transcriptase Polymerase Chain Reaction , Telomerase/genetics , Transcription, Genetic , Vascular Endothelial Growth Factor C/genetics , Vascular Endothelial Growth Factor D/genetics
19.
Clin Radiol ; 62(3): 238-44, 2007 Mar.
Article in English | MEDLINE | ID: mdl-17293217

ABSTRACT

AIM: To highlight the variation in clinical manifestations, imaging and management of four cases of unilateral pulmonary artery agenesis presenting in adulthood. METHOD: Four patients with unilateral pulmonary artery agenesis were referred to our institution between 1995 and 2005. They underwent a series of investigations, including chest radiography, echocardiography, ventilation perfusion scintigraphy, angiography, computed tomography (CT) and magnetic resonance imaging (MRI). RESULTS: Two of the four patients had absence of the right main pulmonary artery, whilst the remaining two patients had absence of the left main pulmonary artery. One patient showed a restrictive defect on pulmonary function tests. Two patients who had ventilation perfusion scintigraphy showed absent perfusion and reduced ventilation on the affected side. Angiography (where performed), CT and MRI confirmed the anatomy and the presence of multiple collaterals. Bronchiectasis was demonstrated on CT in two patients, with one also demonstrating a mosaic attenuation pattern. One patient had an incidental lung tumour on the side of the agenesis, which was diagnosed as a chondroid hamartoma on histology. Three of the four patients eventually underwent resection of the affected lung. CONCLUSION: Isolated unilateral pulmonary artery agenesis has a non-specific presentation. Awareness of this condition can lead to earlier diagnosis, with cross-sectional imaging making an important contribution.


Subject(s)
Pulmonary Artery/abnormalities , Pulmonary Artery/diagnostic imaging , Adult , Aged , Bronchiectasis/diagnostic imaging , Bronchiectasis/etiology , Collateral Circulation , Female , Humans , Hypertension, Pulmonary/diagnostic imaging , Hypertension, Pulmonary/etiology , Magnetic Resonance Angiography , Male , Pneumonectomy , Pulmonary Artery/pathology , Recurrence , Respiratory Tract Infections/etiology , Tomography, X-Ray Computed
20.
Infect Immun ; 75(3): 1099-115, 2007 Mar.
Article in English | MEDLINE | ID: mdl-17130251

ABSTRACT

Campylobacter jejuni is a globally distributed cause of human food-borne enteritis and has been linked to chronic joint and neurological diseases. We hypothesized that C. jejuni 11168 colonizes the gastrointestinal tract of both C57BL/6 mice and congenic C57BL/6 interleukin-10-deficient (IL-10(-/-)) mice and that C57BL/6 IL-10(-/-) mice experience C. jejuni 11168-mediated clinical signs and pathology. Individually housed mice were challenged orally with C. jejuni 11168, and the course of infection was monitored by clinical examination, bacterial culture, C. jejuni-specific PCR, gross pathology, histopathology, immunohistochemistry, and anti-C. jejuni-specific serology. Ceca of C. jejuni 11168-infected mice were colonized at high rates: ceca of 50/50 wild-type mice and 168/170 IL-10(-/-) mice were colonized. In a range from 2 to 35 days after infection with C. jejuni 11168, C57BL/6 IL-10(-/-) mice developed severe typhlocolitis best evaluated at the ileocecocolic junction. Rates of colonization and enteritis did not differ between male and female mice. A dose-response experiment showed that as little as 10(6) CFU produced significant disease and pathological lesions similar to responses seen in humans. Immunohistochemical staining demonstrated C. jejuni antigens within gastrointestinal tissues of infected mice. Significant anti-C. jejuni plasma immunoglobulin levels developed by day 28 after infection in both wild-type and IL-10-deficient animals; antibodies were predominantly T-helper-cell 1 (Th1)-associated subtypes. These results indicate that the colonization of the mouse gastrointestinal tract by C. jejuni 11168 is necessary but not sufficient for the development of enteritis and that C57BL/6 IL-10(-/-) mice can serve as models for the study of C. jejuni enteritis in humans.


Subject(s)
Campylobacter Infections/microbiology , Campylobacter jejuni/pathogenicity , Enteritis/microbiology , Interleukin-10/deficiency , Interleukin-10/genetics , Animals , Animals, Congenic , Campylobacter Infections/genetics , Campylobacter Infections/immunology , Disease Models, Animal , Enteritis/genetics , Enteritis/immunology , Humans , Mice , Mice, Inbred C57BL , Mice, Knockout
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