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Pregnancy is associated with an increased risk of vitamin D deficiency beyond that of the general population. The aim of the current analysis was to synthesize the current evidence on the dose-outcome relationship of vitamin D/serum 25 hydroxyvitamin D (25-OHD) and complications during pregnancy. An additional aim was to estimate the economic burden attributable to inadequate levels of serum 25-OHD. Published literature on the effects of vitamin D supplementation/serum 25-OHD on pregnancy complications, including randomized control trials and non-interventional studies, was searched in bibliographic databases including Pubmed, Google Scholar, Scopus and EMBASE. A positive and significant treatment effect was obtained for pre-eclampsia (OR = 0.75 95% CI 0.662-0.843), but not for preterm birth (OR = 0.783, 95% CI 0.49-1.251) or small for gestational age (OR = 0.76 95% CI 0.38-1.28). Inadequate vitamin D accounted for 14.04% of risk for pre-eclampsia. It is estimated that addressing vitamin D inadequacy in pregnant women in England and Wales would reduce the number of cases of pre-eclampsia by 4126; and would result in a net saving of £18.6 million for the NHS in England and Wales. The current results suggest that based on current evidence a public health policy preventing vitamin D inadequacy in pregnant women is likely to have a positive impact on the NHS budget in England and Wales. This is contingent upon further evidence regarding the vitamin D dose-pregnancy outcome relationship becoming available.
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Complicaciones del Embarazo/economía , Deficiencia de Vitamina D/economía , Femenino , Humanos , Embarazo , Complicaciones del Embarazo/epidemiología , Reino Unido/epidemiología , Deficiencia de Vitamina D/epidemiologíaRESUMEN
Blood flukes of the genus Schistosoma infect over 200 million people, causing granulomatous pathology with accompanying morbidity and mortality. As a consequence of extensive host-parasite co-evolution, schistosomes exhibit a complex relationship with their hosts, in which immunological factors are intimately linked with parasite development. Schistosomes fail to develop normally in immunodeficient mice, an outcome specifically dependent on the absence of CD4⺠T cells. The role of CD4⺠T cells in parasite development is indirect and mediated by interaction with innate cells, as repeated toll-like receptor 4 stimulation is sufficient to restore parasite development in immunodeficient mice in the absence of CD4⺠T cells. Here we show that repeated stimulation of innate immunity by an endogenous danger signal can also restore parasite development and that both these stimuli, when administered repeatedly, lead to the regulation of innate responses. Supporting a role for regulation of innate responses in parasite development, we show that regulation of inflammation by neutralizing anti-TNF antibodies also restores parasite development in immunodeficient mice. Finally, we show that administration of IL-4 to immunodeficient mice to regulate inflammation by induction of type 2 responses also restores parasite development. These findings suggest that the type 2 response driven by CD4⺠T cells during pre-patent infection of immunocompetent hosts is exploited by schistosomes to complete their development to reproductively mature adult parasites.
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Inmunidad Innata , Schistosoma/inmunología , Esquistosomiasis/inmunología , Células Th2/inmunología , Receptor Toll-Like 4/inmunología , Animales , Anticuerpos Neutralizantes/inmunología , Anticuerpos Neutralizantes/farmacología , Humanos , Interleucina-4/genética , Interleucina-4/inmunología , Ratones , Ratones Noqueados , Esquistosomiasis/genética , Esquistosomiasis/patología , Células Th2/patología , Receptor Toll-Like 4/genética , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Factor de Necrosis Tumoral alfa/genética , Factor de Necrosis Tumoral alfa/inmunologíaRESUMEN
Basophils play a key role in the development and effector phases of type 2 immune responses in both allergic diseases and helminth infections. This study shows that basophils become less responsive to IgE-mediated stimulation when mice are chronically infected with Litomosoides sigmodontis, a filarial nematode, and Schistosoma mansoni, a blood fluke. Although excretory/secretory products from microfilariae of L. sigmodontis suppressed basophils in vitro, transfer of microfilariae into mice did not result in basophil suppression. Rather, reduced basophil responsiveness, which required the presence of live helminths, was found to be dependent on host IL-10 and was accompanied by decreases in key IgE signaling molecules known to be downregulated by IL-10. Given the importance of basophils in the development of type 2 immune responses, these findings help explain the mechanism by which helminths protect against allergy and may have broad implications for understanding how helminth infections alter other disease states in people.
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Basófilos/inmunología , Filariasis/inmunología , Filarioidea/inmunología , Interleucina-10/inmunología , Schistosoma mansoni/inmunología , Esquistosomiasis mansoni/inmunología , Animales , Basófilos/metabolismo , Enfermedad Crónica , Regulación hacia Abajo/genética , Regulación hacia Abajo/inmunología , Femenino , Filariasis/genética , Filariasis/metabolismo , Filarioidea/metabolismo , Inmunoglobulina E/genética , Inmunoglobulina E/inmunología , Inmunoglobulina E/metabolismo , Interleucina-10/genética , Interleucina-10/metabolismo , Ratones , Ratones Endogámicos BALB C , Ratones Noqueados , Schistosoma mansoni/metabolismo , Esquistosomiasis mansoni/genética , Esquistosomiasis mansoni/metabolismo , Transducción de Señal/genética , Transducción de Señal/inmunología , Células Th2/inmunología , Células Th2/metabolismoRESUMEN
Leading hypotheses to explain helminth-mediated protection against autoimmunity postulate that type 2 or regulatory immune responses induced by helminth infections in the host limit pathogenic Th1-driven autoimmune responses. We tested these hypotheses by investigating whether infection with the filarial nematode Litomosoides sigmodontis prevents diabetes onset in IL-4-deficient NOD mice and whether depletion or absence of regulatory T cells, IL-10, or TGF-ß alters helminth-mediated protection. In contrast to IL-4-competent NOD mice, IL-4-deficient NOD mice failed to develop a type 2 shift in either cytokine or Ab production during L. sigmodontis infection. Despite the absence of a type 2 immune shift, infection of IL-4-deficient NOD mice with L. sigmodontis prevented diabetes onset in all mice studied. Infections in immunocompetent and IL-4-deficient NOD mice were accompanied by increases in CD4(+)CD25(+)Foxp3(+) regulatory T cell frequencies and numbers, respectively, and helminth infection increased the proliferation of CD4(+)Foxp3(+) cells. However, depletion of CD25(+) cells in NOD mice or Foxp3(+) T cells from splenocytes transferred into NOD.scid mice did not decrease helminth-mediated protection against diabetes onset. Continuous depletion of the anti-inflammatory cytokine TGF-ß, but not blockade of IL-10 signaling, prevented the beneficial effect of helminth infection on diabetes. Changes in Th17 responses did not seem to play an important role in helminth-mediated protection against autoimmunity, because helminth infection was not associated with a decreased Th17 immune response. This study demonstrates that L. sigmodontis-mediated protection against diabetes in NOD mice is not dependent on the induction of a type 2 immune shift but does require TGF-ß.
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Diabetes Mellitus Tipo 1/prevención & control , Diabetes Mellitus Tipo 1/parasitología , Filariasis/inmunología , Filariasis/parasitología , Filarioidea/inmunología , Células TH1/inmunología , Factor de Crecimiento Transformador beta/biosíntesis , Animales , Diabetes Mellitus Tipo 1/metabolismo , Femenino , Filariasis/metabolismo , Interleucina-10/biosíntesis , Interleucina-10/fisiología , Interleucina-4/deficiencia , Interleucina-4/genética , Ratones , Ratones de la Cepa 129 , Ratones Endogámicos NOD , Ratones Noqueados , Ratones Transgénicos , Linfocitos T Reguladores/inmunología , Linfocitos T Reguladores/metabolismo , Linfocitos T Reguladores/parasitología , Linfocitos T Reguladores/patología , Células TH1/metabolismo , Células TH1/parasitología , Factor de Crecimiento Transformador beta/fisiologíaRESUMEN
This article will provide an overview of the diagnosis of common temporomandibular disorders (TMDs) and bruxism, along with their relevance in management of tooth wear. When assessing and managing a tooth wear case, the teeth should not be considered in isolation, but as part of the articulatory system, which has three inter-related elements: the teeth, the temporomandibular joints and the masticatory muscles. The presence/absence of bruxism and TMD are highly relevant, although there may not be a causal relationship between these. A consideration of TMD and bruxism, together with the potential impact these may have on the patient during and after any management of tooth wear, will form part of patient education and the informed consent process.
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Bruxismo , Trastornos de la Articulación Temporomandibular , Atrición Dental , Humanos , Bruxismo/complicaciones , Bruxismo/diagnóstico , Trastornos de la Articulación Temporomandibular/complicaciones , Trastornos de la Articulación Temporomandibular/diagnóstico , Articulación TemporomandibularRESUMEN
INTRODUCTION: A variety of methods have been used to study inflammatory changes in the acutely injured spinal cord. Recently novel multiplex assays have been used in an attempt to overcome limitations in numbers of available targets studied in a single experiment. Other technical challenges in developing pre-clinical rodent models to investigate biomarkers in cerebrospinal fluid (CSF) include relatively small volumes of sample and low concentrations of target proteins. The primary objective of this study was to characterize the inflammatory profile present in CSF at a subacute time point in a clinically relevant rodent model of traumatic spinal cord injury (SCI). Our other aim was to test a microarray proteomics platform specifically for this application. METHODS: A 34 cytokine sandwich ELISA microarray was used to study inflammatory changes in CSF samples taken 12 days post-cervical SCI in adult rats. The difference between the median foreground signal and the median background signal was measured. Bonferroni and Benjamini-Hochburg multiple testing corrections were applied to limit the False Discovery Rate (FDR), and a linear mixed model was used to account for repeated measures in the array. RESULTS: We report a novel subacute SCI biomarker, elevated levels of matrix metalloproteinase-8 protein in CSF, and discuss application of statistical models designed for multiplex testing. CONCLUSIONS: Major advantages of this assay over conventional methods include high-throughput format, good sensitivity, and reduced sample consumption. This method can be useful for creating comprehensive inflammatory profiles, and biomarkers can be used in the clinic to assess injury severity and to objectively grade response to therapy.
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Metaloproteinasa 8 de la Matriz/biosíntesis , Metaloproteinasa 8 de la Matriz/líquido cefalorraquídeo , Análisis por Matrices de Proteínas/métodos , Proteómica/métodos , Traumatismos de la Médula Espinal/líquido cefalorraquídeo , Traumatismos de la Médula Espinal/enzimología , Animales , Biomarcadores/líquido cefalorraquídeo , Biomarcadores/metabolismo , Vértebras Cervicales/enzimología , Femenino , Ratas , Ratas Sprague-Dawley , Regulación hacia Arriba/fisiologíaRESUMEN
Schistosoma blood flukes, which infect over 200 million people globally, co-opt CD4+ T cell-dependent mechanisms to facilitate parasite development and egg excretion. The latter requires Th2 responses, while the mechanism underpinning the former has remained obscure. Using mice that are either defective in T cell receptor (TCR) signaling or that lack TCRs that can respond to schistosomes, we show that naïve CD4+ T cells facilitate schistosome development in the absence of T cell receptor signaling. Concurrently, the presence of naïve CD4+ T cells correlates with both steady-state changes in the expression of genes that are critical for the development of monocytes and macrophages and with significant changes in the composition of peripheral mononuclear phagocyte populations. Finally, we show that direct stimulation of the mononuclear phagocyte system restores blood fluke development in the absence of CD4+ T cells. Thus we conclude that schistosomes co-opt innate immune signals to facilitate their development and that the role of CD4+ T cells in this process may be limited to the provision of non-cognate help for mononuclear phagocyte function. Our findings have significance for understanding interactions between schistosomiasis and other co-infections, such as bacterial infections and human immunodeficiency virus infection, which potently stimulate innate responses or interfere with T cell help, respectively. An understanding of immunological factors that either promote or inhibit schistosome development may be valuable in guiding the development of efficacious new therapies and vaccines for schistosomiasis.
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Linfocitos T CD4-Positivos/inmunología , Schistosoma mansoni/inmunología , Esquistosomiasis/inmunología , Animales , Citocinas/biosíntesis , Ensayo de Inmunoadsorción Enzimática , Femenino , Expresión Génica , Perfilación de la Expresión Génica , Proteínas del Helminto/inmunología , Activación de Linfocitos/inmunología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Análisis de Secuencia por Matrices de Oligonucleótidos , Receptores de Antígenos de Linfocitos T/inmunologíaRESUMEN
Scar tissue at sites of traumatic injury in the adult central nervous system presents a combined physical and molecular impediment to axon regeneration. Of multiple known central nervous system scar associated axon growth inhibitors, semaphorin 3A has been shown to be strongly expressed by invading leptomeningeal fibroblasts. We have previously demonstrated that infusion of the small leucine-rich proteoglycan decorin results in major suppression of several growth inhibitory chondroitin sulphate proteoglycans and growth of adult sensory axons across acute spinal cord injuries. Furthermore, decorin treatment of leptomeningeal fibroblasts significantly increases their ability to support neurite growth of co-cultured adult dorsal root ganglion neurons. In the present study we show that decorin has the ability to suppress semaphorin 3A expression within adult rat cerebral cortex scar tissue and in primary leptomeningeal fibroblasts in vitro. Infusion of decorin core protein for eight days resulted in a significant reduction of semaphorin 3A messenger RNA expression within injury sites compared with saline-treated control animals. Both in situ hybridization and immunostaining confirmed that semaphorin 3A messenger RNA expression and protein levels are significantly reduced in decorin-treated animals. Similarly, decorin treatment decreased the expression of semaphorin 3A messenger RNA in cultured rat leptomeningeal fibroblasts compared with untreated cells. Mechanistic studies revealed that decorin-mediated suppression of semaphorin 3A critically depends on erythroblastic leukaemia viral oncogene homologue B4 and signal transducer and activator of transcription 3 function. Collectively, our studies show that in addition to suppressing the levels of inhibitory chondroitin sulphate proteoglycans, decorin has the ability to suppress semaphorin 3A in the injured central nervous system. Our findings provide further evidence for the use of decorin as a potential therapy for promoting axonal growth and repair in the injured adult mammalian brain and spinal cord.
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Corteza Cerebral/metabolismo , Cicatriz/metabolismo , Decorina/metabolismo , Receptores ErbB/metabolismo , Factor de Transcripción STAT3/metabolismo , Semaforina-3A/metabolismo , Animales , Células Cultivadas , Corteza Cerebral/efectos de los fármacos , Corteza Cerebral/patología , Decorina/farmacología , Femenino , Fibroblastos/citología , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Inmunohistoquímica , Hibridación in Situ , Regeneración Nerviosa/fisiología , Neuronas/metabolismo , Neuronas/patología , Ratas , Ratas Sprague-Dawley , Receptor ErbB-4 , Reacción en Cadena de la Polimerasa de Transcriptasa InversaRESUMEN
Introduction Trismus has been identified as a red flag sign that may lead to an early identification of a malignant lesion. A simple checklist was devised to allow clinicians to identify patients who may be at risk.Methods The implementation of this checklist at the temporomandibular disorder clinic of the University Dental Hospital of Manchester has been audited through ten annual cycles, each examining a sample of 50 clinical records of patients referred to the clinic. The standards set were that the presence of the trismus checklist in new patient examination notes should be 100%, the recording of mouth opening should be 100% and that the trismus checklist should be correctly filled in 100% of the time.Results The incidence of trismus ranged from 0-20%. The presence of the trismus checklist in new patient examination notes ranged from 78-100% compliance. The recording of mouth opening ranged from 80-100% compliance. The trismus checklist was not always filled in correctly: it ranged from 50-100%.Conclusion The use of audit has led to the evolution of the checklist and to improvements in its implementation. The trismus checklist has aided the early identification of malignancy. Future work should look at its implementation in a wider range of settings.
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PURPOSE OF REVIEW: Central to the obstacles to be overcome in moving promising cell-based therapies from the laboratory to the clinic is that of determining which of the many cell types being examined are optimal for repairing particular lesions. RECENT FINDINGS: Our studies on astrocyte replacement therapies demonstrate clearly that some cells are far better than others at promoting recovery in spinal cord injury and that, at least in some cases, transplanting undifferentiated precursor cells is far less useful than transplanting specific astrocytes derived from those precursor cells. But further comparison between different approaches is hindered by the difficulties in replicating results between laboratories, even for well defined pharmacological agents and bioactive proteins. These difficulties in replication appear most likely to be due to unrecognized nuances in lesion characteristics and in the details of delivery of therapies. SUMMARY: We propose that the challenge of reproducibility provides a critical opportunity for refining cell-based therapies. If the utility of a particular approach is so restricted that even small changes in lesions or treatment protocols eliminate benefit, then the variability inherent in clinical injuries will frustrate translation. In contrast, rising to this challenge may enable discovery of refinements needed to confer the robustness needed for successful clinical trials.
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Trasplante de Células/métodos , Enfermedades del Sistema Nervioso Central/terapia , Sistema Nervioso Central/patología , Animales , Astrocitos/trasplante , Enfermedades del Sistema Nervioso Central/patología , Enfermedades del Sistema Nervioso Central/fisiopatología , Ensayos Clínicos como Asunto , Humanos , Reproducibilidad de los Resultados , Traumatismos de la Médula Espinal/terapia , Resultado del TratamientoRESUMEN
The therapeutic and toxic effects of drugs are often generated through effects on distinct cell types in the body. Selective delivery of drugs to specific cells or cell lineages would, therefore, have major advantages, in particular, the potential to significantly improve the therapeutic window of an agent. Cells of the monocyte-macrophage lineage represent an important target for many therapeutic agents because of their central involvement in a wide range of diseases including inflammation, cancer, atherosclerosis, and diabetes. We have developed a versatile chemistry platform that is designed to enhance the potency and delivery of small-molecule drugs to intracellular molecular targets. One facet of the technology involves the selective delivery of drugs to cells of the monocyte-macrophage lineage, using the intracellular carboxylesterase, human carboxylesterase-1 (hCE-1), which is expressed predominantly in these cells. Here, we demonstrate selective delivery of many types of intracellularly targeted small molecules to monocytes and macrophages by attaching a small esterase-sensitive chemical motif (ESM) that is selectively hydrolyzed within these cells to a charged, pharmacologically active drug. ESM versions of histone deacetylase (HDAC) inhibitors, for example, are extremely potent anticytokine and antiarthritic agents with a wider therapeutic window than conventional HDAC inhibitors. In human blood, effects on monocytes (hCE-1-positive) are seen at concentrations 1000-fold lower than those that affect other cell types (hCE-1-negative). Chemical conjugates of this type, by limiting effects on other cells, could find widespread applicability in the treatment of human diseases where monocyte-macrophages play a key role in disease pathology.
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Sistemas de Liberación de Medicamentos/métodos , Esterasas/antagonistas & inhibidores , Esterasas/química , Macrófagos/efectos de los fármacos , Monocitos/efectos de los fármacos , Aminoácidos/química , Animales , Anisomicina/farmacología , Artritis/inmunología , Carboxilesterasa/antagonistas & inhibidores , Carboxilesterasa/química , Carboxilesterasa/genética , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Citocinas/biosíntesis , Citocinas/sangre , Citocinas/genética , Inhibidores Enzimáticos/farmacología , Esterasas/genética , Ésteres/metabolismo , Proteínas HSP90 de Choque Térmico/metabolismo , Humanos , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Lipopolisacáridos/farmacología , Espectroscopía de Resonancia Magnética , Ratones , Ratones Transgénicos , Proteínas Serina-Treonina Quinasas/metabolismo , Transducción de Señal/efectos de los fármacos , Factor de Necrosis Tumoral alfa/biosíntesis , Factor de Necrosis Tumoral alfa/sangre , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismoRESUMEN
A morphometric and molecular study of adult male and female Lutzomyia shannoni (Dyar 1929) collected at seven different locations within the southeastern United States was conducted to assess the degree of divergence between the grouped specimens from each location. The collection locations were as follows: Fort Bragg, NC; Fort Campbell, KY; Fort Rucker, AL; Ossabaw Island, GA; Patuxent National Wildlife Research Refuge, MD; Suwannee National Wildlife Refuge, FL; and Baton Rouge, LA. Forty males and forty females from each location were analyzed morphometrically from 54 and 49 character measurements, respectively. In addition, the molecular markers consisting of the partial cytochrome c oxidase subunit I (from 105 sand flies: 15 specimens/collection site) and the partial internal transcribed spacer 2 (from 42 sand flies: six specimens/collection site) were compared. Multivariate analyses indicate that the low degree of variation between the grouped specimens from each collection site prevents the separation of any collection site into an entity that could be interpreted as a distinct population. The molecular analyses were in concordance with the morphometric study as no collection location grouped into a separate population based on the two partial markers. The grouped specimens from each collection site appear to be within the normal variance of the species, indicating a single population in the southeast United States. It is recommended that additional character analyses of L. shannoni based on more molecular markers, behavioral, ecological, and physiological characteristics, be conducted before ruling out the possibility of populations or a cryptic species complex within the southeastern United States.
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Variación Genética , Psychodidae/anatomía & histología , Psychodidae/genética , Animales , Demografía , Femenino , Masculino , Filogenia , Psychodidae/fisiología , Sudeste de Estados UnidosRESUMEN
During natural schistosome infection, the induction of T helper type 2 (Th2) responses has been ascribed to parasite eggs, because exposure of the host to this life-cycle stage elicits a polarized Th2 response to egg antigens. In the present study, we show that schistosome worms also elicit systemic, antigen-specific type 2 responses during prepatent infection, before egg deposition begins. CD4(+) T cells producing interleukin (IL)-4 were induced by both male and female worms during single-sex infections, demonstrating that this response is independent of exposure to eggs. The Th2 response was accompanied by production of immunoglobulin E and the sensitization of circulating basophils to produce additional IL-4 in response to schistosome antigens. Together, our data show that schistosome worms establish an immunologic milieu where CD4(+) T cells and basophils are both primed to produce IL-4 before eggs are laid, suggesting that worms play a role in establishment of the Th2 response that is critical for host survival and parasite transmission.
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Genes MHC Clase II/genética , Schistosoma mansoni/fisiología , Esquistosomiasis mansoni/inmunología , Animales , Antígenos Helmínticos , Basófilos/fisiología , Linfocitos T CD4-Positivos/metabolismo , Femenino , Humanos , Inmunoglobulina E/sangre , Interleucina-4/genética , Interleucina-4/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Óvulo/inmunologíaRESUMEN
On entering the mammalian host, schistosomes transition from a freshwater environment where resources are scarce, to an environment where there is an unlimited supply of glucose, their preferred energy substrate. Adult schistosome glycolytic activity consumes almost five times the parasite's dry weight in glucose per day to meet the parasite's energy demands, and the schistosome glycolytic enzymes and mechanisms for glucose uptake that sustain this metabolic activity have previously been identified. However, little is known of the parasite processes that regulate schistosome glucose metabolism. We previously described the Schistosoma mansoni ortholog of 5' AMP-Activated Protein Kinase (AMPK), which is a central regulator of energy metabolism in eukaryotes, and characterized the developmental regulation of its expression and activity in S. mansoni. Here we sought to explore the function of AMPK in schistosomes and test whether it regulates parasite glycolysis. Adult schistosomes mounted a compensatory response to chemical inhibition of AMPK α, resulting in increased AMPK α protein abundance and activity. RNAi inhibition of AMPK α expression, however, suggests that AMPK α is not required for adult schistosome viability in vitro. Larval schistosomula, on the other hand, are sensitive to chemical AMPK α inhibition, and this correlates with inactivity of the AMPK α gene in this life cycle stage that precludes a compensatory response to AMPK inhibition. While our data indicate that AMPK is not essential in adult schistosomes, our results suggest that AMPK regulates adult worm glycogen stores, influencing both glycogen utilization and synthesis. AMPK may therefore play a role in the ability of adult schistosomes to survive in vivo stressors such as transient glucose deprivation and oxidative stress. These findings suggest that AMPK warrants further investigation as a potential drug target, especially for interventions aimed at preventing establishment of a schistosome infection.
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BACKGROUND: During the pre-patent stage of infection, juvenile Schistosoma blood flukes co-opt signals from the adaptive immune system to facilitate parasite development, but the types of responses that are induced at this early stage of infection, and the parasite antigens they target, have not been characterized. RESULTS: Through analysis of experimental pre-patent infections, we show that the S. mansoni cysteine protease SmCB1 is rapidly targeted by an antigen-specific IgE response. The induction of this response is independent of schistosome eggs as infection with male or female worms alone also induced SmCB1-specific IgE. We also show that the SmCB1-specific IgE response is dependent on cognate CD4+ T cell help and IL-4, suggesting that pre-patent Th2 responses provide T cell help for the SmCB1-specific IgE response. Finally, exposed human subjects also produced IgE against SmCB1. CONCLUSIONS: Our data demonstrate that, like eggs, schistosome worms also induce functional type 2 responses and that a parasite cysteine protease is an inducer of type 2 responses during the early stages of schistosome infection.
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Catepsina B/metabolismo , Proteínas del Helminto/metabolismo , Interleucina-4/metabolismo , Schistosoma mansoni/inmunología , Esquistosomiasis/inmunología , Células Th2/inmunología , Inmunidad Adaptativa , Animales , Catepsina B/inmunología , Femenino , Proteínas del Helminto/inmunología , Humanos , Inmunoglobulina E/sangre , Interleucina-4/genética , Interleucina-4/inmunología , Estadios del Ciclo de Vida , Masculino , Ratones , Schistosoma mansoni/patogenicidad , Esquistosomiasis/sangre , Balance Th1 - Th2RESUMEN
This report describes two male specimens of the sand fly species Lutzomyia shannoni (Dyar) (Diptera: Psychodidae: Phlebotominae) collected at Fort Rucker, AL, and Fort Campbell, KY, in dry ice-baited light traps during September 2005. The specimens were observed to have anomalies to the number of spines on the gonostyli. The taxonomic keys of Young and Perkins (Mosq. News 44: 263-285; 1984) use the number of spines on the gonostylus in the first couplet to differentiate two major groupings of North American sand flies. The two anomalous specimens were identified as L. shannoni based on the following criteria: (1) both specimens possess antennal ascoids with long, distinct proximal spurs (a near diagnostic character of L. shannoni in North America), (2) the sequences of the partial cytochrome c oxidase subunit 1 gene from both specimens indicated L. shannoni, and (3) the sequences of the internal transcribed spacer 2 molecular marker from both specimens indicated L. shannoni. The anomalous features are fundamentally different from each other as the Fort Rucker specimen possesses a fifth spine (basally located) on just one gonostylus, whereas the Fort Campbell specimen possesses five spines (extra spines subterminally located) on both gonostyli. Because the gonostyli are part of the external male genitalia, anomalies in the number of spines on the gonostyli may have serious biological consequences, such as reduced reproductive success, for the possessors. These anomalies are of taxonomic interest as the specimens could easily have been misidentified using available morphological keys.
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Psychodidae/anatomía & histología , Alabama , Animales , Citocromos c/genética , Regulación Enzimológica de la Expresión Génica , Genitales Masculinos/anatomía & histología , Kentucky , Masculino , Filogenia , Psychodidae/clasificación , Psychodidae/genéticaRESUMEN
cAMP-dependent protein kinases (PKAs) are central mediators of cAMP signaling in eukaryotic cells. Previously we identified a cDNA which encodes for a PKA catalytic subunit (PKA-C) in Schistosoma mansoni (SmPKA-C) that is required for adult schistosome viability in vitro. As such, SmPKA-C could potentially represent a novel schistosome chemotherapeutic target. Here we sought to identify PKA-C subunit orthologues in the other medically important schistosome species, Schistosoma haematobium and Schistosoma japonicum, to determine the degree to which this potential target is conserved and could therefore be exploited for the treatment of all forms of schistosomiasis. We report the identification of PKA-C subunit orthologues in S. haematobium and S. japonicum (ShPKA-C and SjPKA-C, respectively) and show that PKA-C orthologues are highly conserved in the Schistosoma, with over 99% amino acid sequence identity shared among the three human pathogens we examined. Furthermore, we show that the recently published Schistosoma mansoni and S. japonicum genomes contain sequences encoding for several putative PKA substrates with homology to those found in Homo sapiens, Caenorhabditis elegans, and Saccharomyces cerevisiae.
Asunto(s)
Secuencia Conservada , Subunidades Catalíticas de Proteína Quinasa Dependientes de AMP Cíclico/química , Schistosoma haematobium/enzimología , Schistosoma japonicum/enzimología , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Clonación Molecular , Cricetinae , Subunidades Catalíticas de Proteína Quinasa Dependientes de AMP Cíclico/genética , Subunidades Catalíticas de Proteína Quinasa Dependientes de AMP Cíclico/metabolismo , ADN Complementario/química , Humanos , Ratones , Datos de Secuencia Molecular , Filogenia , Schistosoma haematobium/genética , Schistosoma japonicum/genética , Alineación de SecuenciaRESUMEN
The seasonal abundance and temporal patterns of the adult sand fly (Lutzomyia shannoni Dyar) were examined at the Patuxent National Wildlife Research Refuge, MD, from August 3, 2005, to July 29, 2006. A total of 138 (53 males, 85 females) L. shannoni was collected from 4 dry ice-baited traps set at the same 4 locations throughout the study. The male:female ratio was 1:2.4. All 4 traps, separated by a maximum distance of approximately 1.6 km, operated simultaneously on the collection dates. The collection dates were spaced apart by near weekly intervals during the months of expected sand fly activity. No collections occurred in December-February. August was clearly the period of peak adult abundance as the numbers collected were significantly greater during this month than any other month of collection. Results indicate the existence of a unimodal pattern of abundance with adult emergence beginning in June and ending by September. The temporal pattern and abundance differ from what has been observed for the species on Ossabaw Island, a barrier island located along coastal Georgia, and at San Felasco Hammock Preserve State Park, Gainesville, FL. Continued research is needed to compile multiyear data to confirm the temporal abundance patterns of this species in Maryland.