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1.
BMC Public Health ; 22(1): 1092, 2022 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-35650565

RESUMEN

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.


Asunto(s)
Dieta , Salud Pública , Niño , Preescolar , Ejercicio Físico , Femenino , Estilo de Vida Saludable , Humanos , Madres
2.
J Autoimmun ; 77: 11-38, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27939129

RESUMEN

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.


Asunto(s)
Antibacterianos/efectos adversos , Infecciones por Campylobacter/complicaciones , Infecciones por Campylobacter/microbiología , Campylobacter jejuni , Síndrome de Guillain-Barré/etiología , Síndrome de Guillain-Barré/patología , Animales , Antibacterianos/farmacología , Anticuerpos Antibacterianos/inmunología , Autoanticuerpos/inmunología , Infecciones por Campylobacter/tratamiento farmacológico , Citocinas/sangre , Citocinas/metabolismo , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Ganglios Espinales/inmunología , Ganglios Espinales/metabolismo , Ganglios Espinales/patología , Síndrome de Guillain-Barré/fisiopatología , Inmunoglobulina G/inmunología , Ratones , Ratones Endogámicos NOD , Ratones Noqueados , Nervios Periféricos/metabolismo , Nervios Periféricos/patología , Nervios Periféricos/fisiopatología , Nervios Periféricos/virología , Fenotipo , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/metabolismo
3.
Microb Pathog ; 54: 1-19, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22960579

RESUMEN

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.


Asunto(s)
Infecciones por Campylobacter/inmunología , Infecciones por Campylobacter/patología , Campylobacter jejuni/inmunología , Campylobacter jejuni/patogenicidad , Interleucina-10/deficiencia , Sistemas de Lectura Abierta , Factores de Virulencia/genética , Animales , Infecciones por Campylobacter/microbiología , Campylobacter jejuni/clasificación , Campylobacter jejuni/genética , Femenino , Expresión Génica , Genotipo , Interleucina-10/genética , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Tipificación de Secuencias Multilocus , Virulencia , Factores de Virulencia/metabolismo
4.
Perspect Public Health ; : 17579139231205488, 2023 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-37850725

RESUMEN

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.

5.
BMJ Mil Health ; 2023 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-37400128

RESUMEN

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.

6.
Harmful Algae ; 99: 101919, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-33218444

RESUMEN

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.


Asunto(s)
Bivalvos , Diatomeas , Animales , Acuicultura , Fitoplancton , Mariscos
7.
Microb Pathog ; 47(1): 38-46, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19409975

RESUMEN

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.


Asunto(s)
Campylobacter jejuni/inmunología , Campylobacter jejuni/patogenicidad , Células Epiteliales/microbiología , Interleucina-4/inmunología , Animales , Membrana Celular/ultraestructura , Células Cultivadas , Citoplasma/microbiología , Citoplasma/ultraestructura , Células Epiteliales/ultraestructura , Escherichia coli/inmunología , Escherichia coli/patogenicidad , Interleucina-10/inmunología , Mucosa Intestinal/citología , Microscopía , Microscopía Electrónica de Transmisión , Proteínas Recombinantes/inmunología , Porcinos
8.
Vet Parasitol ; 153(1-2): 24-43, 2008 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-18342449

RESUMEN

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.


Asunto(s)
Enfermedades de las Aves/parasitología , Sarcocystis/aislamiento & purificación , Sarcocistosis/veterinaria , Pájaros Cantores/parasitología , Animales , Caballos , Interacciones Huésped-Parásitos , Interferón gamma/genética , Interferón gamma/metabolismo , Ratones , Ratones Noqueados , Músculo Esquelético/parasitología , Zarigüeyas/parasitología , Filogenia , Reacción en Cadena de la Polimerasa/veterinaria , Polimorfismo de Longitud del Fragmento de Restricción , Sarcocystis/genética , Sarcocistosis/parasitología , Sensibilidad y Especificidad , Piel/citología , Piel/parasitología , Organismos Libres de Patógenos Específicos
9.
Mol Biol Cell ; 16(2): 943-53, 2005 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-15574883

RESUMEN

Senescence, the molecular program that limits the finite proliferative potential of a cell, acts as an important barrier to protect the body from cancer. Techniques for measuring transcriptome changes and for modulating their expression suggest that it may be possible to dissect the transcriptional networks underlying complex cellular processes. HMF3A cells are conditionally immortalized human mammary fibroblasts that can be induced to undergo coordinated senescence. Here, we used these cells in conjunction with microarrays, RNA interference, and in silico promoter analysis to promote the dissection of the transcriptional networks responsible for regulating cellular senescence. We first identified changes in the transcriptome when HMF3A cells undergo senescence and then compared them with those observed upon replicative senescence in primary human mammary fibroblasts. In addition to DUSP1 and known p53 and E2F targets, a number of genes such as PHLDA1, NR4A3, and a novel splice variant of STAC were implicated in senescence. Their role in senescence was then analyzed by RNA silencing followed by microarray analysis. In silico promoter analysis of all differential genes predicted that nuclear factor-kappaB and C/EBP transcription factors are activated upon senescence, and we confirmed this by electrophoretic mobility shift assay. The results suggest a putative signaling network for cellular senescence.


Asunto(s)
Senescencia Celular , Senescencia Celular/genética , Fibroblastos/metabolismo , Transcripción Genética , Proteínas de Ciclo Celular/genética , Línea Celular Transformada , Células Cultivadas , Senescencia Celular/fisiología , Medio de Cultivo Libre de Suero , Proteínas de Unión al ADN/genética , Fosfatasa 1 de Especificidad Dual , Ensayo de Cambio de Movilidad Electroforética , Femenino , Regulación de la Expresión Génica , Silenciador del Gen , Humanos , Proteínas Inmediatas-Precoces/genética , Glándulas Mamarias Humanas/citología , Análisis por Micromatrices , Modelos Biológicos , FN-kappa B/metabolismo , Proteínas del Tejido Nervioso/genética , Fosfoproteínas Fosfatasas/genética , Regiones Promotoras Genéticas , Proteína Fosfatasa 1 , Proteínas Tirosina Fosfatasas/genética , Interferencia de ARN , Empalme del ARN , Receptores de Esteroides , Receptores de Hormona Tiroidea , Retroviridae/genética , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Proteína p53 Supresora de Tumor/genética
10.
Anticancer Res ; 27(4B): 2265-8, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17695512

RESUMEN

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.


Asunto(s)
Neoplasias de la Mama/metabolismo , Metaloproteinasa 1 de la Matriz/biosíntesis , ARN Mensajero/biosíntesis , Telomerasa/biosíntesis , Factor C de Crecimiento Endotelial Vascular/biosíntesis , Factor D de Crecimiento Endotelial Vascular/biosíntesis , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Humanos , Estadificación de Neoplasias , ARN Mensajero/genética , Receptor PAR-1/biosíntesis , Receptor PAR-1/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Telomerasa/genética , Transcripción Genética , Factor C de Crecimiento Endotelial Vascular/genética , Factor D de Crecimiento Endotelial Vascular/genética
11.
Sci Rep ; 7(1): 13788, 2017 10 23.
Artículo en Inglés | MEDLINE | ID: mdl-29062098

RESUMEN

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.

12.
Vet Parasitol ; 135(3-4): 223-34, 2006 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-16280197

RESUMEN

The objective of this study was to evaluate the utility of a simple, efficient, and rapid method for the isolation of Sarcocystis neurona merozoites and Besnoitia darlingi tachyzoites from cultured cells. The efficacy of this purification method was assessed by microscopy, SDS-PAGE, Western blotting, immuno-fluorescence, and three novel quantitative PCR assays. Culture medium containing host cell debris and parasites was eluted through PD-10 desalting columns. This purification method was compared to alternatives employing filtration through a cellulose filter pad or filter paper. The estimated recovery of S. neurona merozoites purified by the column method was 82% (+/-3.7) of the original merozoites with 97.5% purity. In contrast, estimated recovery of S. neurona merozoites purified by filter pad and filter paper was 40% and 30% with 76% and 83% purity, respectively. The same procedures were applied to purify B. darlingi tachyzoites from cultured cells. Of the original cultured B. darlingi tachyzoites, 94% (+/-2.5) were recovered from the PD-10 column with 96.5%, purity whereas percentage recovery of B. darlingi tachyzoites purified by filter pad and filter paper were 51% and 35% with 84% and 88% purity, respectively. All described methods maintained sterility so that purified parasites could be subsequently cultured in vitro. However, purification using a PD-10 column minimized parasite loss and the loss of viability as determined by the trypan blue dye exclusion assay, the rate of parasite production, and plaque forming efficiency in cell culture. Moreover, column-purified parasites improved the sensitivity of an immuno-fluorescent (IFA) analysis and real-time quantitative PCR assays targeted to parasite 18S ribosomal DNA and hsp70 genes. This technique appears generally applicable for purifying coccidia grown in cell cultures.


Asunto(s)
Reacción en Cadena de la Polimerasa/veterinaria , Sarcocystidae/aislamiento & purificación , Sarcocystis/aislamiento & purificación , Animales , Western Blotting/métodos , Western Blotting/veterinaria , Células Cultivadas/parasitología , Electroforesis en Gel de Poliacrilamida/métodos , Electroforesis en Gel de Poliacrilamida/veterinaria , Técnica del Anticuerpo Fluorescente/métodos , Técnica del Anticuerpo Fluorescente/veterinaria , Microscopía/métodos , Microscopía/veterinaria , Reacción en Cadena de la Polimerasa/métodos , Sensibilidad y Especificidad
14.
Vet Parasitol ; 131(3-4): 317-24, 2005 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-15978725

RESUMEN

Immune responses to gastrointestinal helminth infections have received increasing attention due to similarities to allergen-induced responses. In fact, the whipworm parasite of swine, Trichuris suis, has been used in beginning clinical trials as an antidote to inflammatory bowel disease. This strategy was based on this similarity and the recognition that other worms have been documented to induce anti-inflammatory responses in the host. In an effort to understand the basis for this response, we hypothesized that the proteins and peptides secreted by T. suis stimulate local intestinal epithelial cells to produce anti-inflammatory cytokines. To test this hypothesis in a correlate system of the natural swine host, T. suis excretory secretory products (ESP) were used to treat both differentiated and undifferentiated intestinal pig epithelial cells (IPEC-1) in vitro as a model for the effect on villus tip and crypt epithelial cells in the vicinity of the worms. IPEC-1 were exposed to low-level doses (0.3mg/ml) of T. suis ESP, and IL-4, IL-6 and IL-10 cytokine responses were measured by an enzyme-linked immunosorbant assay (ELISA). IL-6 was the predominant cytokine produced, accompanied by moderate IL-10 secretion from both differentiated and undifferentiated cells. As expected, IL-4 was not produced by IPEC-1. Additionally, IL-6 and IL-10 cytokines were produced within 24h, suggesting that these two cytokines form part of the primary host response to T. suis infections. These data suggest that T. suis ESP could enhance host immune responses and modulation through the induction of enteric IL-6 and IL-10.


Asunto(s)
Antígenos Helmínticos/inmunología , Enfermedades Gastrointestinales/veterinaria , Interleucina-10/metabolismo , Interleucina-6/metabolismo , Enfermedades de los Porcinos/parasitología , Tricuriasis/veterinaria , Trichuris/inmunología , Animales , Ensayo de Inmunoadsorción Enzimática/veterinaria , Células Epiteliales , Enfermedades Gastrointestinales/inmunología , Enfermedades Gastrointestinales/parasitología , Interleucina-10/inmunología , Interleucina-6/inmunología , Mucosa Intestinal/inmunología , Mucosa Intestinal/metabolismo , Porcinos , Enfermedades de los Porcinos/inmunología , Tricuriasis/inmunología , Tricuriasis/parasitología
15.
Vet Parasitol ; 127(1): 3-8, 2005 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-15619368

RESUMEN

Equine protozoal myeloencephalitis (EPM) is a serious neurological disease of horses in Americans. Most cases are attributed to infection of the central nervous system with Sarcocystis neurona. Parasitemia has not been demonstrated in immunocompetent horses, but has been documented in one immunocompromised foal. The objective of this study was to isolate viable S. neurona from the blood of immunocompetent horses. Horses used in this study received orally administered S. neurona sporocysts (strain SN 37-R) daily for 112 days at the following doses: 100/day for 28 days, followed by 500/day for 28 days, followed by 1000/day for 56 days. On day 98 of the study, six yearling colts were selected for attempted culture of S. neurona from blood, two testing positive, two testing suspect and two testing negative for antibodies against S. neurona on day 84 of the study. Two 10 ml tubes with EDTA were filled from each horse by jugular venipuncture and the plasma fraction rich in mononuclear cells was pipetted onto confluent equine dermal cell cultures. The cultures were monitored weekly for parasite growth for 12 weeks. Merozoites grown from cultures were harvested and tested using S. neurona-specific PCR with RFLP to confirm species identity. PCR products were sequenced and compared to known strains of S. neurona. After 38 days of in vitro incubation, one cell culture from a horse testing positive for antibodies against S. neurona was positive for parasite growth while the five remaining cultures remained negative for parasite growth for all 12 weeks. The Sarcocystis isolate recovered from cell culture was confirmed to be S. neurona by PCR with RFLP. Gene sequence analysis revealed that the isolate was identical to the challenge strain SN-37R and differed from two known strains UCD1 and MIH1. To our knowledge this is the first report of parasitemia with S. neurona in an immunocompetent horse.


Asunto(s)
Enfermedades de los Caballos/parasitología , Parasitemia/veterinaria , Sarcocystis/aislamiento & purificación , Sarcocistosis/veterinaria , Animales , Anticuerpos Antiprotozoarios/sangre , Anticuerpos Antiprotozoarios/líquido cefalorraquídeo , Secuencia de Bases , ADN Protozoario/química , ADN Protozoario/genética , Enfermedades de los Caballos/sangre , Caballos , Masculino , Datos de Secuencia Molecular , Parasitemia/sangre , Parasitemia/inmunología , Parasitemia/parasitología , Reacción en Cadena de la Polimerasa/veterinaria , Polimorfismo de Longitud del Fragmento de Restricción , Sarcocystis/genética , Sarcocystis/inmunología , Sarcocistosis/sangre , Sarcocistosis/inmunología , Sarcocistosis/parasitología , Alineación de Secuencia , Análisis de Secuencia de ADN
16.
Arch Intern Med ; 140(7): 929-33, 1980 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-7387302

RESUMEN

Two patients with chronic meningococcemia were found to lack hemolytic complement, one because of C6 deficiency, the other because of C7 deficiency. In both cases family studies were consistent with inheritance of the deficiencies as non-HLA-linked, autosomal co-dominant traits. Functional studies showed the deficient sera to support monocyte chemotaxis but not phagocytosis or lysis of meningococci. Both patients have remained well following antibiotic treatment.


Asunto(s)
Complemento C6/deficiencia , Complemento C7/deficiencia , Infecciones Meningocócicas/complicaciones , Adolescente , Preescolar , Complemento C6/análisis , Complemento C7/análisis , Humanos , Masculino , Infecciones Meningocócicas/inmunología , Linaje , Sepsis/complicaciones , Sepsis/inmunología
17.
Rev Sci Instrum ; 86(1): 013907, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25638097

RESUMEN

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.

18.
J Immunol Methods ; 30(3): 201-7, 1979.
Artículo en Inglés | MEDLINE | ID: mdl-501103

RESUMEN

Quantitative hemolytic assays for C6 and C7 using as R reagents sera from patients deficient in these components are described. The assays gave linear results. Normal range for serum C6 was found to be 21,400--41,700 C6 hemolytic units/ml; for serum C7 the normal range was 5540--9860 C7 hemolytic units/ml.


Asunto(s)
Complemento C6/deficiencia , Complemento C7/deficiencia , Hemólisis , Animales , Quimiotaxis , Vía Alternativa del Complemento , Eritrocitos/inmunología , Humanos , Conejos , Ovinos , Factores de Tiempo
19.
Am J Med ; 111 Suppl 8A: 3S-7S, 2001 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-11749916

RESUMEN

The human tendency to have gastroesophageal reflux is a result of the upright stance, with the head and pelvis in the same plane, and bipedal locomotion. Compared with quadrupedal mammals, human embryologic developments shift in orientation, so that the ventral surface becomes anterior, the dorsal surface becomes posterior, anterior becomes dorsal, and posterior becomes ventral. Shifts in the position of the stomach and esophagus lead to relatively ineffective cardioesophageal sphincter mechanisms. This lends itself to reflux and reflux-associated problems. By the end of fetal development, all of the changes are present.


Asunto(s)
Esófago/embriología , Reflujo Gastroesofágico/embriología , Sistema Respiratorio/embriología , Estómago/embriología , Animales , Perros , Desarrollo Embrionario y Fetal/fisiología , Humanos , Postura , Sensibilidad y Especificidad , Especificidad de la Especie
20.
Chest ; 109(4): 945-52, 1996 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8635375

RESUMEN

Nedocromil sodium and cromolyn sodium are the only two currently available nonsteroid anti-inflammatory agents for treatment of asthma. Clinical differences between the two agents remain under continuous investigation with reports differentiating the two on the basis of atopy of the patient and reversibility of bronchoconstriction. This study investigated the efficacy of nedocromil sodium (4 mg, qid) for treatment of mild-to-moderate asthma in comparison to placebo using cromolyn sodium (2 mg, qid) as an active control treatment. Patients were primarily allergic asthmatics (with at least 15% reversibility) previously maintained on a regimen of regular bronchodilator therapy. During a 2-week run-in period, the patient's slow-release theophylline therapy was removed, and the patients were randomized to treatment after deterioration of asthma control (asthma symptom summary score of 3 for 7 of the 14 days). After 8 weeks of treatment, patients were returned to as occasion requires bronchodilator therapy, as per the 2-week baseline period. The results demonstrate that patients treated with nedocromil sodium showed statistically significant improvements during the primary time period (mean weeks 3 through 8) over placebo-treated patients as evidenced by all indexes of asthma symptoms, pulmonary function measures, and decreased bronchodilator reliance (p<0.05). Patients treated with cromolyn sodium demonstrated similar improvements over placebo-treated patients. Comparisons between nedocromil sodium and cromolyn sodium showed the two agents to be comparable in this group of primarily allergic patients with reversible disease. Between-group differences were noted for 3 of the 13 variables (nighttime asthma, FEV1, and forced expiratory flow rate between 25 % and 75% of the FVC) in favor of cromolyn sodium when the data were pooled during the primary time period. The number of patients missing 1 or more days from work/school/regular activity due to asthma was significantly fewer compared with placebo, and favoring nedocromil sodium over cromolyn sodium. No differences were observed among the three treatments for adverse events. This study demonstrated that in primarily allergic patients with reversible airways disease, nedocromil sodium and cromolyn sodium are both significantly more effective than placebo for treatment of mild-to-moderate asthma.


Asunto(s)
Antiasmáticos/uso terapéutico , Asma/prevención & control , Cromolin Sódico/uso terapéutico , Nedocromil/uso terapéutico , Actividades Cotidianas , Adolescente , Adulto , Anciano , Antiasmáticos/efectos adversos , Asma/inmunología , Asma/fisiopatología , Broncodilatadores/efectos adversos , Broncodilatadores/uso terapéutico , Ritmo Circadiano , Tos/prevención & control , Cromolin Sódico/efectos adversos , Método Doble Ciego , Femenino , Estudios de Seguimiento , Humanos , Pulmón/efectos de los fármacos , Masculino , Persona de Mediana Edad , Nedocromil/efectos adversos , Cooperación del Paciente , Placebos , Pruebas de Función Respiratoria
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