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1.
PLoS Pathog ; 17(7): e1009709, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34237106

RESUMEN

Helminths are distinct from microbial pathogens in both size and complexity, and are the likely evolutionary driving force for type 2 immunity. CD4+ helper T cells can both coordinate worm clearance and prevent immunopathology, but issues of T cell antigen specificity in the context of helminth-induced Th2 and T regulatory cell (Treg) responses have not been addressed. Herein, we generated a novel transgenic line of the gastrointestinal nematode Strongyloides ratti expressing the immunodominant CD4+ T cell epitope 2W1S as a fusion protein with green fluorescent protein (GFP) and FLAG peptide in order to track and study helminth-specific CD4+ T cells. C57BL/6 mice infected with this stable transgenic line (termed Hulk) underwent a dose-dependent expansion of activated CD44hiCD11ahi 2W1S-specific CD4+ T cells, preferentially in the lung parenchyma. Transcriptional profiling of 2W1S-specific CD4+ T cells isolated from mice infected with either Hulk or the enteric bacterial pathogen Salmonella expressing 2W1S revealed that pathogen context exerted a dominant influence over CD4+ T cell phenotype. Interestingly, Hulk-elicited 2W1S-specific CD4+ T cells exhibited both Th2 and Treg phenotypes and expressed high levels of the EGFR ligand amphiregulin, which differed greatly from the phenotype of 2W1S-specific CD4+ T cells elicited by 2W1S-expressing Salmonella. While immunization with 2W1S peptide did not enhance clearance of Hulk infection, immunization did increase total amphiregulin production as well as the number of amphiregulin-expressing CD3+ cells in the lung following Hulk infection. Altogether, this new model system elucidates effector as well as immunosuppressive and wound reparative roles of helminth-specific CD4+ T cells. This report establishes a new resource for studying the nature and function of helminth-specific T cells.


Asunto(s)
Epítopos de Linfocito T/genética , Estrongiloidiasis/inmunología , Linfocitos T Reguladores/inmunología , Células Th2/inmunología , Animales , Animales Modificados Genéticamente , Antígenos Helmínticos , Linfocitos T CD4-Positivos/inmunología , Modelos Animales de Enfermedad , Epítopos de Linfocito T/inmunología , Ratones , Ratones Endogámicos C57BL , Strongyloides ratti/inmunología
2.
Proc Natl Acad Sci U S A ; 117(7): 3711-3717, 2020 02 18.
Artículo en Inglés | MEDLINE | ID: mdl-32015105

RESUMEN

Mosquito-borne helminth infections are responsible for a significant worldwide disease burden in both humans and animals. Accordingly, development of novel strategies to reduce disease transmission by targeting these pathogens in the vector are of paramount importance. We found that a strain of Aedes aegypti that is refractory to infection by Dirofilaria immitis, the agent of canine heartworm disease, mounts a stronger immune response during infection than does a susceptible strain. Moreover, activation of the Toll immune signaling pathway in the susceptible strain arrests larval development of the parasite, thereby decreasing the number of transmission-stage larvae. Notably, this strategy also blocks transmission-stage Brugia malayi, an agent of human lymphatic filariasis. Our data show that mosquito immunity can play a pivotal role in restricting filarial nematode development and suggest that genetically engineering mosquitoes with enhanced immunity will help reduce pathogen transmission.


Asunto(s)
Aedes/inmunología , Aedes/parasitología , Dirofilaria immitis/crecimiento & desarrollo , Mosquitos Vectores/inmunología , Mosquitos Vectores/parasitología , Aedes/genética , Animales , Proteínas de Insectos/genética , Proteínas de Insectos/inmunología , Larva/crecimiento & desarrollo , Mosquitos Vectores/genética
3.
Sex Abuse ; 35(2): 241-260, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35507760

RESUMEN

Sexual recidivism risk assessment tools focus almost exclusively on risk factors associated with increased rates of recidivism and do not attend to protective factors that might mitigate reoffense risk. The present study investigated the predictive validity of the Structured Assessment of Protective Factors - Sexual Offence version (SAPROF-SO), developed to assess hypothesised protective factors against sexual recidivism in adult males. The SAPROF-SO pilot version contains 24 items across two domains: Personal and Professionally Provided Support. SAPROF-SO scores were rated retrospectively from a review of archived case files of 210 men with convictions for child sexual offenses, using the SAPROF-SO pilot manual and a supplementary retrospective scoring guide developed for the current study. SAPROF-SO Total and Personal domain scores were significantly predictive of sexual recidivism after an average follow-up period of 12.24 years (AUC = .81), and to a lesser extent, violent and general recidivism. SAPROF-SO Total and Personal scores additionally provided significant incremental validity over Static-99R scores in the prediction of sexual recidivism. Results support the predictive validity of protective factors for reduced sexual recidivism and invite future research examining how to integrate the SAPROF-SO alongside contemporary sexual recidivism risk assessment tools.


Asunto(s)
Criminales , Reincidencia , Delitos Sexuales , Adulto , Masculino , Niño , Humanos , Factores Protectores , Estudios Retrospectivos , Delitos Sexuales/prevención & control , Reincidencia/prevención & control , Medición de Riesgo/métodos
4.
Proc Natl Acad Sci U S A ; 115(1): 204-209, 2018 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-29203662

RESUMEN

Strongyloides stercoralis hyperinfection causes high mortality rates in humans, and, while hyperinfection can be induced by immunosuppressive glucocorticoids, the pathogenesis remains unknown. Since immunocompetent mice are resistant to infection with S. stercoralis, we hypothesized that NSG mice, which have a reduced innate immune response and lack adaptive immunity, would be susceptible to the infection and develop hyperinfection. Interestingly, despite the presence of large numbers of adult and first-stage larvae in S. stercoralis-infected NSG mice, no hyperinfection was observed even when the mice were treated with a monoclonal antibody to eliminate residual granulocyte activity. NSG mice were then infected with third-stage larvae and treated for 6 wk with methylprednisolone acetate (MPA), a synthetic glucocorticoid. MPA treatment of infected mice resulted in 50% mortality and caused a significant >10-fold increase in the number of parasitic female worms compared with infected untreated mice. In addition, autoinfective third-stage larvae, which initiate hyperinfection, were found in high numbers in MPA-treated, but not untreated, mice. Remarkably, treatment with Δ7-dafachronic acid, an agonist of the parasite nuclear receptor Ss-DAF-12, significantly reduced the worm burden in MPA-treated mice undergoing hyperinfection with S. stercoralis Overall, this study provides a useful mouse model for S. stercoralis autoinfection and suggests a therapeutic strategy for treating lethal hyperinfection.


Asunto(s)
Colestenos/farmacología , Metilprednisolona/análogos & derivados , Strongyloides stercoralis/inmunología , Estrongiloidiasis/tratamiento farmacológico , Estrongiloidiasis/inmunología , Animales , Colestenos/efectos adversos , Femenino , Metilprednisolona/efectos adversos , Metilprednisolona/farmacología , Acetato de Metilprednisolona , Ratones , Estrongiloidiasis/patología
5.
J Am Anim Hosp Assoc ; 57(5)2021 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-34370849

RESUMEN

An 11 yr old mixed-breed dog presented with a 2 × 3 cm semimovable subcutaneous soft-tissue mass overlying the right hip region that grew to 8 × 5 cm over a 6 mo period. Two separate fine needle aspiration cytology samples showed marked pyogranulomatous inflammation with no cytologically apparent infectious etiology or neoplasia. Computed tomography imaging revealed a well-marginated, heterogeneous, contrast-enhancing soft-tissue mass extending into the adjacent fat, suggestive of neoplasia. A 14G needle biopsy showed similar chronic inflammatory changes without evidence of neoplasia or infectious etiology. Excisional biopsy of the mass was performed, and ex vivo sectioning revealed Taenia crassiceps cysticerci. Histopathology confirmed severe chronic pyogranulomatous cellulitis and myositis with intralesional cysticerci. Anthelmintic treatment was administered postoperatively, and no evidence of local recurrence has been noted as of 6 mo after the operation. To our knowledge, this is the first case report describing the cytological, histological, cross-sectional imaging characteristics and treatment outcome of T crassiceps cysticercosis in a dog.


Asunto(s)
Cisticercosis , Enfermedades de los Perros , Taenia , Animales , Cisticercosis/diagnóstico , Cisticercosis/tratamiento farmacológico , Cisticercosis/cirugía , Cisticercosis/veterinaria , Enfermedades de los Perros/tratamiento farmacológico , Enfermedades de los Perros/cirugía , Perros
6.
Artículo en Inglés | MEDLINE | ID: mdl-29109160

RESUMEN

Meropenem-vaborbactam (Vabomere) is highly active against Gram-negative pathogens, especially Klebsiella pneumoniae carbapenemase (KPC)-producing, carbapenem-resistant Enterobacteriaceae The objective of these studies was to evaluate the efficacy of meropenem alone and in combination with vaborbactam in mouse thigh and lung infection models. Thighs or lungs of neutropenic mice were infected with KPC-producing carbapenem-resistant Enterobacteriaceae, with meropenem MICs ranging from ≤0.06 to 8 mg/liter in the presence of 8 mg/liter vaborbactam. Mice were treated with meropenem alone or meropenem in combination with vaborbactam every 2 h for 24 h to provide exposures comparable to 2-g doses of each component in humans. Meropenem administered in combination with vaborbactam produced bacterial killing in all strains tested, while treatment with meropenem alone either produced less than 0.5 log CFU/tissue of bacterial killing or none at all. In the thigh model, 11 strains were treated with the combination of meropenem plus vaborbactam (300 plus 50 mg/kg of body weight). This combination produced from 0.8 to 2.89 logs of bacterial killing compared to untreated controls at the start of treatment. In the lung infection model, two strains were treated with the same dosage regimen of meropenem and vaborbactam. The combination produced more than 1.83 logs of bacterial killing against both strains tested compared to untreated controls at the start of treatment. Overall, these data suggest that meropenem-vaborbactam may have utility in the treatment of infections due to KPC-producing carbapenem-resistant Enterobacteriaceae.


Asunto(s)
Antibacterianos/uso terapéutico , Ácidos Borónicos/uso terapéutico , Enterobacteriaceae Resistentes a los Carbapenémicos/efectos de los fármacos , Enterobacter cloacae/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Klebsiella pneumoniae/efectos de los fármacos , Meropenem/uso terapéutico , Infecciones del Sistema Respiratorio/tratamiento farmacológico , Infecciones de los Tejidos Blandos/tratamiento farmacológico , Inhibidores de beta-Lactamasas/uso terapéutico , Animales , Antibacterianos/farmacocinética , Proteínas Bacterianas/metabolismo , Ácidos Borónicos/farmacocinética , Enterobacteriaceae Resistentes a los Carbapenémicos/aislamiento & purificación , Modelos Animales de Enfermedad , Combinación de Medicamentos , Femenino , Humanos , Meropenem/farmacocinética , Ratones , Pruebas de Sensibilidad Microbiana , Neutropenia/tratamiento farmacológico , Infecciones del Sistema Respiratorio/microbiología , Infecciones del Sistema Respiratorio/patología , Infecciones de los Tejidos Blandos/microbiología , Muslo/microbiología , Muslo/patología , Inhibidores de beta-Lactamasas/farmacocinética , beta-Lactamasas/metabolismo
7.
Artículo en Inglés | MEDLINE | ID: mdl-29133570

RESUMEN

The objective of these studies was to evaluate the exposures of meropenem and vaborbactam that would produce antibacterial activity and prevent resistance development in carbapenem-resistant Klebsiella pneumoniae carbapenemase (KPC)-producing Enterobacteriaceae strains when tested at an inoculum of 108 CFU/ml. Thirteen K. pneumoniae isolates, three Enterobacter cloacae isolates, and one Escherichia coli isolate were examined in an in vitro hollow-fiber model over 32 h. Simulated dosage regimens of 1 to 2 g of meropenem with 1 to 2 g of vaborbactam, with meropenem administered every 8 h by a 3-h infusion based on phase 1 or phase 3 patient pharmacokinetic data, were studied in the model. A dosage of 2 g of meropenem in combination with 2 g of vaborbactam was bactericidal against K. pneumoniae, E. cloacae, and E. coli strains, with meropenem-vaborbactam MICs of up to 8 mg/liter. When the vaborbactam exposure was adjusted to the levels observed in patients enrolled in phase 3 trials (24-h free AUC, ∼550 mg · h/liter, versus 320 mg · h/liter in the phase 1 studies), 2 g of meropenem with 2 g of vaborbactam was also bactericidal against strains with meropenem-vaborbactam MICs of 16 mg/liter. In addition, this level of vaborbactam also suppressed the development of resistance observed using phase 1 exposures. In this pharmacodynamic model, exposures similar to 2 g of meropenem in combination with 2 g of vaborbactam administered every 8 h by a 3-h infusion in phase 3 trials produced antibacterial activity and suppressed the development of resistance against carbapenem-resistant KPC-producing strains of Enterobacteriaceae.


Asunto(s)
Antibacterianos/farmacología , Ácidos Borónicos/farmacología , Enterobacteriaceae Resistentes a los Carbapenémicos/efectos de los fármacos , Infecciones por Enterobacteriaceae/tratamiento farmacológico , Meropenem/farmacología , Proteínas Bacterianas/metabolismo , Infecciones por Enterobacteriaceae/metabolismo , Humanos , Pruebas de Sensibilidad Microbiana/métodos
8.
PLoS Pathog ; 12(1): e1005358, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26727267

RESUMEN

The complex life cycle of the parasitic nematode Strongyloides stercoralis leads to either developmental arrest of infectious third-stage larvae (iL3) or growth to reproductive adults. In the free-living nematode Caenorhabditis elegans, analogous determination between dauer arrest and reproductive growth is governed by dafachronic acids (DAs), a class of steroid hormones that are ligands for the nuclear hormone receptor DAF-12. Biosynthesis of DAs requires the cytochrome P450 (CYP) DAF-9. We tested the hypothesis that DAs also regulate S. stercoralis development via DAF-12 signaling at three points. First, we found that 1 µM Δ7-DA stimulated 100% of post-parasitic first-stage larvae (L1s) to develop to free-living adults instead of iL3 at 37°C, while 69.4±12.0% (SD) of post-parasitic L1s developed to iL3 in controls. Second, we found that 1 µM Δ7-DA prevented post-free-living iL3 arrest and stimulated 85.2±16.9% of larvae to develop to free-living rhabditiform third- and fourth-stages, compared to 0% in the control. This induction required 24-48 hours of Δ7-DA exposure. Third, we found that the CYP inhibitor ketoconazole prevented iL3 feeding in host-like conditions, with only 5.6±2.9% of iL3 feeding in 40 µM ketoconazole, compared to 98.8±0.4% in the positive control. This inhibition was partially rescued by Δ7-DA, with 71.2±16.4% of iL3 feeding in 400 nM Δ7-DA and 35 µM ketoconazole, providing the first evidence of endogenous DA production in S. stercoralis. We then characterized the 26 CYP-encoding genes in S. stercoralis and identified a homolog with sequence and developmental regulation similar to DAF-9. Overall, these data demonstrate that DAF-12 signaling regulates S. stercoralis development, showing that in the post-parasitic generation, loss of DAF-12 signaling favors iL3 arrest, while increased DAF-12 signaling favors reproductive development; that in the post-free-living generation, absence of DAF-12 signaling is crucial for iL3 arrest; and that endogenous DA production regulates iL3 activation.


Asunto(s)
Colestenos/metabolismo , Proteínas del Helminto/metabolismo , Strongyloides stercoralis/crecimiento & desarrollo , Strongyloides stercoralis/metabolismo , Secuencia de Aminoácidos , Animales , Modelos Animales de Enfermedad , Perros , Regulación del Desarrollo de la Expresión Génica/fisiología , Genes de Helminto , Gerbillinae , Proteínas del Helminto/genética , Larva/metabolismo , Estadios del Ciclo de Vida , Receptores Citoplasmáticos y Nucleares/genética , Receptores Citoplasmáticos y Nucleares/metabolismo , Strongyloides stercoralis/genética , Estrongiloidiasis/metabolismo
9.
PLoS Pathog ; 10(8): e1004305, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25121736

RESUMEN

Skin-penetrating parasitic nematodes infect approximately one billion people worldwide and are responsible for some of the most common neglected tropical diseases. The infective larvae of skin-penetrating nematodes are thought to search for hosts using sensory cues, yet their host-seeking behavior is poorly understood. We conducted an in-depth analysis of host seeking in the skin-penetrating human parasite Strongyloides stercoralis, and compared its behavior to that of other parasitic nematodes. We found that Str. stercoralis is highly mobile relative to other parasitic nematodes and uses a cruising strategy for finding hosts. Str. stercoralis shows robust attraction to a diverse array of human skin and sweat odorants, most of which are known mosquito attractants. Olfactory preferences of Str. stercoralis vary across life stages, suggesting a mechanism by which host seeking is limited to infective larvae. A comparison of odor-driven behavior in Str. stercoralis and six other nematode species revealed that parasite olfactory preferences reflect host specificity rather than phylogeny, suggesting an important role for olfaction in host selection. Our results may enable the development of new strategies for combating harmful nematode infections.


Asunto(s)
Quimiotaxis/fisiología , Interacciones Huésped-Parásitos/fisiología , Nematodos/fisiología , Infecciones por Nematodos , Piel/parasitología , Animales , Escarabajos/parasitología , Gerbillinae , Humanos , Masculino , Ratas , Ratas Long-Evans , Ratas Sprague-Dawley
10.
PLoS Pathog ; 8(8): e1002871, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22912584

RESUMEN

Genetic transformation is a potential tool for analyzing gene function and thereby identifying new drug and vaccine targets in parasitic nematodes, which adversely affect more than one billion people. We have previously developed a robust system for transgenesis in Strongyloides spp. using gonadal microinjection for gene transfer. In this system, transgenes are expressed in promoter-regulated fashion in the F1 but are silenced in subsequent generations, presumably because of their location in repetitive episomal arrays. To counteract this silencing, we explored transposon-mediated chromosomal integration of transgenes in S. ratti. To this end, we constructed a donor vector encoding green fluorescent protein (GFP) under the control of the Ss-act-2 promoter with flanking inverted tandem repeats specific for the piggyBac transposon. In three experiments, free-living Strongyloides ratti females were transformed with this donor vector and a helper plasmid encoding the piggyBac transposase. A mean of 7.9% of F1 larvae were GFP-positive. We inoculated rats with GFP-positive F1 infective larvae, and 0.5% of 6014 F2 individuals resulting from this host passage were GFP-positive. We cultured GFP-positive F2 individuals to produce GFP-positive F3 L3i for additional rounds of host and culture passage. Mean GFP expression frequencies in subsequent generations were 15.6% in the F3, 99.0% in the F4, 82.4% in the F5 and 98.7% in the F6. The resulting transgenic lines now have virtually uniform GFP expression among all progeny after at least 10 generations of passage. Chromosomal integration of the reporter transgenes was confirmed by Southern blotting and splinkerette PCR, which revealed the transgene flanked by S. ratti genomic sequences corresponding to five discrete integration sites. BLAST searches of flanking sequences against the S. ratti genome revealed integrations in five contigs. This result provides the basis for two powerful functional genomic tools in S. ratti: heritable transgenesis and insertional mutagenesis.


Asunto(s)
Animales Modificados Genéticamente , Elementos Transponibles de ADN , Strongyloides ratti , Estrongiloidiasis/parasitología , Transgenes , Animales , Animales Modificados Genéticamente/genética , Animales Modificados Genéticamente/metabolismo , Femenino , Vectores Genéticos , Gerbillinae , Proteínas Fluorescentes Verdes/biosíntesis , Proteínas Fluorescentes Verdes/genética , Regiones Promotoras Genéticas , Ratas , Strongyloides ratti/genética , Strongyloides ratti/metabolismo , Estrongiloidiasis/genética , Estrongiloidiasis/metabolismo , Transformación Genética
11.
J Orthop Sports Phys Ther ; 54(2): 1-6, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37904496

RESUMEN

BACKGROUND: Restoring quadriceps strength is essential for successful rehabilitation of knee injuries, but many athletes return to their previous activity with persisting muscle weakness. Strong evidence supports using neuromuscular electrical stimulation (NMES) to improve quadriceps strength; however, there is a lack of widespread clinical implementation. We believe there is a critical need to provide clinical approaches that promote using NMES to improve patients' quadriceps strength and ensuring clinicians provide high-value rehabilitation care. CLINICAL QUESTION: What is best practice when using NMES to facilitate strength after injury, what are barriers to its use, and how can they be addressed? KEY RESULTS: We discuss the low clinical implementation of NMES, perceived barriers to using NMES, and provide recommendations for setup and dosage parameters for effective use of NMES. CLINICAL APPLICATION: We aim for this commentary, with accompanying videos, to serve as a resource for clinicians who are using commercially available NMES units in clinical practice. J Orthop Sports Phys Ther 2024;54(2):1-6. Epub 31 October 2023. doi:10.2519/jospt.2023.12028.


Asunto(s)
Lesiones del Ligamento Cruzado Anterior , Terapia por Estimulación Eléctrica , Humanos , Lesiones del Ligamento Cruzado Anterior/rehabilitación , Articulación de la Rodilla , Rodilla , Músculo Cuádriceps/fisiología , Estimulación Eléctrica , Fuerza Muscular/fisiología
12.
ACR Open Rheumatol ; 6(1): 32-42, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37966058

RESUMEN

OBJECTIVE: Virtual care (VC) is an accepted modality of care delivery, and shared decision-making (SDM) benefits patients with rheumatologic and chronic conditions (RCCs). Unfortunately, research suggests reduced quality of SDM during VC. This study explores the benefits and shortcomings of SDM regarding RCCs during VC with suggestions for optimally using VC during SDM. METHODS: Following Stiggelbout's framework for SDM, we conducted focus groups of patients with RCCs and providers to understand their experiences with SDM during VC, probing for facilitating and challenging factors. We conducted content analysis of the transcripts, defining themes, and inductively reasoned to identify relationships among themes. We summarized the facilitators, barriers, and opportunities for improving SDM during VC that participants proposed. RESULTS: Virtual SDM shares several similarities with in-person practice, as both draw upon trusting patient-provider relationships, following the same general steps, and relying on effective communication. VC presents solutions for known barriers to in-person SDM, expanding time for making decisions and access to care. Technology and virtual health systems introduce new barriers to SDM, and participants list opportunities for overcoming these concerns. CONCLUSION: VC is a tool that can enhance and even support superior SDM compared with in-person visits when implemented successfully, a condition requiring the development of nuanced skills to correctly identify when and how to best use VC for SDM as well as technology and health care structures that integrate SDM into VC. Therefore, patients, providers, insurance carriers, and policy makers all contribute to the success of SDM among RCCs during VC.

13.
Infect Immun ; 81(9): 3346-55, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23798541

RESUMEN

Macrophages are multifunctional cells that are active in TH1- and TH2-mediated responses. In this study, we demonstrate that human and mouse macrophages collaborate with neutrophils and complement to kill the parasite Strongyloides stercoralis in vitro. Infection of mice with worms resulted in the induction of alternatively activated macrophages (AAM) within the peritoneal cavity. These cells killed the worms in vivo and collaborated with neutrophils and complement during the in vitro killing process. AAM generated in vitro killed larvae more rapidly than naive macrophages, which killed larvae after a longer time period. In contrast, classically activated macrophages were unable to kill larvae either in vitro or in vivo. This study adds macrophages to the armamentarium of immune components that function in elimination of parasitic helminths and demonstrate a novel function by which AAM control large extracellular parasites.


Asunto(s)
Larva/inmunología , Macrófagos/inmunología , Neutrófilos/inmunología , Strongyloides stercoralis/inmunología , Animales , Células Cultivadas , Proteínas del Sistema Complemento/inmunología , Humanos , Inmunoglobulina M/inmunología , Péptidos y Proteínas de Señalización Intercelular , Interleucina-4/inmunología , Ratones , Ratones Endogámicos C57BL , Cavidad Peritoneal/parasitología , Estrongiloidiasis/inmunología , Estrongiloidiasis/parasitología
14.
J Vet Intern Med ; 37(2): 735-739, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36821075

RESUMEN

A 5-year-old imported Zangersheide gelding was evaluated for SC swellings over both forelimbs and lameness localized to the distal metacarpus. Ultrasound examination of the SC masses was compatible with verminous granulomas. Linear hyperechoic foci were present within the suspensory ligament branches of both forelimbs, suggestive of ligamentous parasitic infiltrates. A diagnosis of onchocerciasis was confirmed on biopsy of a SC mass. The gelding was treated with ivermectin and a tapering course of PO dexamethasone but was eventually euthanized. Necropsy confirmed the presence of SC eosinophilic granulomas and degenerative suspensory ligament desmitis, both with intralesional nematodes. Given the location and appearance of the nematode, a diagnosis of Onchocerca sp., most likely O. reticulata, was made. Onchocerciasis should be included as a differential diagnosis for multifocal suspensory ligament desmitis with these sonographic characteristics when paired with SC masses in imported European Warmbloods.


Asunto(s)
Artritis , Enfermedades de los Caballos , Enfermedades Musculares , Oncocercosis , Animales , Caballos , Masculino , Onchocerca , Oncocercosis/diagnóstico , Oncocercosis/parasitología , Oncocercosis/patología , Oncocercosis/veterinaria , Ligamentos/patología , Artritis/veterinaria , Enfermedades Musculares/patología , Enfermedades Musculares/veterinaria , Enfermedades de los Caballos/diagnóstico por imagen , Enfermedades de los Caballos/tratamiento farmacológico
15.
Infect Immun ; 79(7): 2770-8, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21482685

RESUMEN

Eosinophils and neutrophils contribute to larval killing during the primary immune response, and neutrophils are effector cells in the secondary response to Strongyloides stercoralis in mice. The objective of this study was to determine the molecular mechanisms used by eosinophils and neutrophils to control infections with S. stercoralis. Using mice deficient in the eosinophil granule products major basic protein (MBP) and eosinophil peroxidase (EPO), it was determined that eosinophils kill the larvae through an MBP-dependent mechanism in the primary immune response if other effector cells are absent. Infecting PHIL mice, which are eosinophil deficient, with S. stercoralis resulted in development of primary and secondary immune responses that were similar to those of wild-type mice, suggesting that eosinophils are not an absolute requirement for larval killing or development of secondary immunity. Treating PHIL mice with a neutrophil-depleting antibody resulted in a significant impairment in larval killing. Naïve and immunized mice with neutrophils deficient in myeloperoxidase (MPO) infected with S. stercoralis had significantly decreased larval killing. It was concluded that there is redundancy in the primary immune response, with eosinophils killing the larvae through an MBP-dependent mechanism and neutrophils killing the worms through an MPO-dependent mechanism. Eosinophils are not required for the development or function of secondary immunity, but MPO from neutrophils is required for protective secondary immunity.


Asunto(s)
Proteína Mayor Básica del Eosinófilo/metabolismo , Eosinófilos/inmunología , Neutrófilos/inmunología , Peroxidasa/metabolismo , Strongyloides stercoralis/inmunología , Estrongiloidiasis/inmunología , Animales , Proteína Mayor Básica del Eosinófilo/genética , Proteína Mayor Básica del Eosinófilo/inmunología , Eosinófilos/metabolismo , Larva/inmunología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Neutrófilos/metabolismo , Peroxidasa/genética , Estrongiloidiasis/prevención & control
16.
Diagnostics (Basel) ; 11(6)2021 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-34071716

RESUMEN

Strongyloidiasis, caused mainly by the nematode Strongyloides stercoralis, is prevalent worldwide and potentially fatal in immunosuppressed patients. We report on a new IgE biomarker to diagnose Strongyloides infection. Sera from two groups infected with Strongyloides served as positive samples: Group 1A, in which infection was confirmed by stool-microscopy and/or stool-polymerase chain reaction (PCR) and was seropositive by an IgG-enzyme linked immunosorbent assay (ELISA) and an IgG4 rapid test, and Group 1B in which infection was confirmed by stool-PCR but was seronegative. Negative samples (controls) comprised infections with other parasites (Group II) and healthy donors (Group III). Immunoscreenings of an S. stercoralis complementary DNA (cDNA) library were performed, and the cDNA clone with the highest diagnostic potential (clone A133) was selected for recombinant protein production and then evaluated using IgE Western blot and ELISA. The Western blot showed that the recombinant protein (rA133) was 100% reactive with Group IA (n = 10) and Group IB (n = 5), and 96% non-reactive with Groups II and III (n = 25). Subsequently, the IgE-ELISA was developed and showed 100% diagnostic sensitivity in Groups IA (n = 32) and IB (n = 11); and 99.3% specificity in Groups II and III (n = 144). In conclusion, this study has identified rA133 as a novel recombinant protein with potential diagnostic value, and that the IgE-ELISA incorporating this protein may be useful for patient diagnosis and epidemiological studies.

17.
Parasit Vectors ; 14(1): 30, 2021 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-33413579

RESUMEN

BACKGROUND: Mosquitoes transmit filarial nematodes to both human and animal hosts, with worldwide health and economic consequences. Transmission to a vertebrate host requires that ingested microfilariae develop into infective third-stage larvae capable of emerging from the mosquito proboscis onto the skin of the host during blood-feeding. Determining the number of microfilariae that successfully develop to infective third-stage larvae in the mosquito host is key to understanding parasite transmission potential and to developing new strategies to block these worms in their vector. METHODS: We developed a novel method to efficiently assess the number of infective third-stage filarial larvae that emerge from experimentally infected mosquitoes. Following infection, individual mosquitoes were placed in wells of a multi-well culture plate and warmed to 37 °C to stimulate parasite emergence. Aedes aegypti infected with Dirofilaria immitis were used to determine infection conditions and assay timing. The assay was also tested with Brugia malayi-infected Ae. aegypti. RESULTS: Approximately 30% of Ae. aegypti infected with D. immitis and 50% of those infected with B. malayi produced emerging third-stage larvae. Once D. immitis third-stage larvae emerged at 13 days post infection, the proportion of mosquitoes producing them and the number produced per mosquito remained stable until at least day 21. The prevalence and intensity of emerging third-stage B. malayi were similar on days 12-14 post infection. Increased uptake of D. immitis microfilariae increased the fitness cost to the mosquito but did not increase the number of emerging third-stage larvae. CONCLUSIONS: We provide a new assay with an associated set of infection conditions that will facilitate assessment of the filarial transmission potential of mosquito vectors and promote preparation of uniformly infectious third-stage larvae for functional assays. The ability to quantify infection outcome will facilitate analyses of molecular interactions between vectors and filariae, ultimately allowing for the establishment of novel methods to block disease transmission.


Asunto(s)
Aedes/parasitología , Bioensayo/métodos , Brugia Malayi/fisiología , Dirofilaria immitis/fisiología , Larva/fisiología , Mosquitos Vectores/parasitología , Animales , Brugia Malayi/aislamiento & purificación , Dirofilaria immitis/aislamiento & purificación , Dirofilariasis/parasitología , Dirofilariasis/transmisión , Microfilarias/fisiología
18.
Sci Rep ; 11(1): 8254, 2021 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-33859232

RESUMEN

The human and canine parasitic nematode Strongyloides stercoralis utilizes an XX/XO sex determination system, with parasitic females reproducing by mitotic parthenogenesis and free-living males and females reproducing sexually. However, the genes controlling S. stercoralis sex determination and male development are unknown. We observed precocious development of rhabditiform males in permissive hosts treated with corticosteroids, suggesting that steroid hormones can regulate male development. To examine differences in transcript abundance between free-living adult males and other developmental stages, we utilized RNA-Seq. We found two clusters of S. stercoralis-specific genes encoding predicted transmembrane proteins that are only expressed in free-living males. We additionally identified homologs of several genes important for sex determination in Caenorhabditis species, including mab-3, tra-1, fem-2, and sex-1, which may have similar functions. However, we identified three paralogs of gld-1; Ss-qki-1 transcripts were highly abundant in adult males, while Ss-qki-2 and Ss-qki-3 transcripts were highly abundant in adult females. We also identified paralogs of pumilio domain-containing proteins with sex-specific transcripts. Intriguingly, her-1 appears to have been lost in several parasite lineages, and we were unable to identify homologs of tra-2 outside of Caenorhabditis species. Together, our data suggest that different mechanisms control male development in S. stercoralis and Caenorhabditis species.


Asunto(s)
Caenorhabditis/genética , Genes de Helminto/genética , Genes de Helminto/fisiología , Proteínas del Helminto/genética , Proteínas del Helminto/fisiología , Procesos de Determinación del Sexo/genética , Strongyloides stercoralis/genética , Transcripción Genética , Animales , Caenorhabditis/fisiología , Femenino , Hormonas Esteroides Gonadales/fisiología , Masculino , Modelos Genéticos , Strongyloides stercoralis/fisiología
19.
Parasit Vectors ; 14(1): 439, 2021 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-34465379

RESUMEN

BACKGROUND: Companion animal endoparasites play a substantial role in both veterinary medicine and public health. Updated epidemiological studies are necessary to identify trends in occurrence and distribution of these parasites, and their associated risk factors. This study aimed to assess the occurrence of canine endoparasites  retrospectively, using fecal flotation  test data available through participating academic veterinary parasitology diagnostic laboratories across the United States of America (USA). METHODS: Canine fecal flotation records from ten veterinary diagnostic laboratories located in nine states in the USA acquired from January 1, 2018, to December 31, 2018, were included. RESULTS: A total of 4692 fecal flotation test results were obtained, with a majority comprised of client-owned dogs (3262; 69.52%), followed by research dogs (375; 8.00%), and shelter dogs (122; 2.60%). Samples from 976 (20.80%) dogs were positive for at least one parasite, and co-infections of two or more parasites were found in 3.82% (179/4692) of the samples. The five most commonly detected parasites were: Giardia sp., (8.33%; 391/4692), Ancylostomatidae (5.63%; 264/4692), Cystoisospora spp. (4.35%; 204/4692), Toxocara canis (2.49%;117/4692), and Trichuris vulpis (2.43%; 114/4692). Various other internal parasites, including gastrointestinal and respiratory nematodes, cestodes, trematodes, and protozoans were detected in less than 1% of samples. CONCLUSIONS: These data illustrate the importance of parasite prevention, routine fecal screening, and treatment of pet dogs. Additionally, pet owners should be educated about general parasite prevalence, prevention, and anthelmintic treatment regimens to reduce the risks of environmental contamination and zoonotic transmission.


Asunto(s)
Técnicas de Laboratorio Clínico/métodos , Técnicas de Laboratorio Clínico/veterinaria , Enfermedades de los Perros/diagnóstico , Heces/parasitología , Parasitosis Intestinales/diagnóstico , Parásitos/aislamiento & purificación , Animales , Técnicas de Laboratorio Clínico/estadística & datos numéricos , Enfermedades de los Perros/parasitología , Perros , Femenino , Parasitosis Intestinales/epidemiología , Masculino , Parásitos/clasificación , Parásitos/genética , Estudios Retrospectivos , Estados Unidos/epidemiología
20.
Int Urogynecol J ; 21(8): 995-1000, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20333504

RESUMEN

INTRODUCTION AND HYPOTHESIS: The objective of this study is to define the diagnosis of hypertrophic cervical elongation clinically and to perform histochemical and histological evaluations of patients with and without hypertrophic cervical elongation. METHODS: This prospective study was conducted at Louisiana State University between December 2005 and May 2008. Fourteen women with cervical elongation and 28 women without prolapse were studied. RESULTS: The amounts of elastin, collagen, and smooth muscle did not differ between study and control groups. Estrogen and progesterone receptor content in cervical elongation were elevated compared to the cervix of women without prolapse. Hypertrophic cervical elongation was defined as the difference between point C and point D of the Pelvic Organ Prolapse Quantification system greater than 8 cm. CONCLUSIONS: Estrogen and progesterone receptor levels are greater in women with hypertrophic cervical elongation compared with a normal cervix.


Asunto(s)
Cuello del Útero/patología , Prolapso de Órgano Pélvico/diagnóstico , Prolapso de Órgano Pélvico/patología , Adulto , Estudios de Casos y Controles , Cuello del Útero/metabolismo , Colágeno/metabolismo , Elastina/metabolismo , Femenino , Humanos , Hipertrofia/diagnóstico , Hipertrofia/metabolismo , Hipertrofia/patología , Persona de Mediana Edad , Prolapso de Órgano Pélvico/metabolismo , Proyectos Piloto , Estudios Prospectivos , Receptores de Estrógenos/metabolismo , Receptores de Progesterona/metabolismo , Estudios Retrospectivos
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