Publications by authors named "Julia Romano"

Article Synopsis
  • The parasite has specific genes for a type I cytochrome P450 enzyme (TgCYP450mt) and a MAPR (TgMAPR), which are crucial for steroid metabolism and are located in the mitochondria; deletion of these genes leads to growth and fitness issues in the parasite.
  • Mutants lacking TgCYP450mt and TgMAPR showed reduced virulence in mice and lower steroid levels, indicating that these proteins are essential for a functioning steroidogenic pathway in Toxoplasma.
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is an obligate, intracellular parasite. Infection of a cell produces a unique niche for the parasite named the parasitophorous vacuole (PV) initially composed of host plasma membrane invaginated during invasion. The PV and its membrane (parasitophorous vacuole membrane [PVM]) are subsequently decorated with a variety of parasite proteins allowing the parasite to optimally grow in addition to manipulate host processes.

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Intracellular pathogens exploit cellular resources through host cell manipulation. Within its nonfusogenic parasitophorous vacuole (PV), Toxoplasma gondii targets host nutrient-filled organelles and sequesters them into the PV through deep invaginations of the PV membrane (PVM) that ultimately detach from this membrane. Some of these invaginations are generated by an intravacuolar network (IVN) of parasite-derived tubules attached to the PVM.

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The intracellular parasite Toxoplasma gondii adapts to diverse host cell environments within a replicative compartment that is heavily decorated by secreted proteins. In an attempt to identify novel parasite secreted proteins that influence host cell activity, we identified and characterized a transmembrane dense granule protein dubbed GRA64 (TGME49_202620). We found that GRA64 is on the parasitophorous vacuolar membrane (PVM) and is partially exposed to the host cell cytoplasm in both tachyzoite and bradyzoite parasitophorous vacuoles.

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The Apicomplexa are famously named for their apical complex, a constellation of organelles at their apical end dedicated to invasion of their host cells. In contrast, at the other end of the cell, the basal complex (BC) has been overshadowed since it is much less prominent and specific functions were not immediately obvious. However, in the past decade a staggering array of functions have been associated with the BC and strides have been made in understanding its structure.

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After mammalian cell invasion, the parasite multiplies in a self-made membrane-bound compartment, the parasitophorous vacuole (PV). We previously showed that interacts with many host cell organelles, especially from recycling pathways, and sequestrates Rab11A and Rab11B vesicles into the PV. Here, we examine the specificity of host Rab11 vesicle interaction with the PV by focusing on the recruitment of subpopulations of Rab11 vesicles characterized by different effectors, for example, Rab11-family interacting roteins (FIPs) or Arf6.

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Background: Negative bias in facial emotion recognition is a well-established concept in mental disorders such as depression. However, existing face sets of emotion recognition tests may be of limited use in international research, which could benefit from more contemporary and diverse alternatives. Here, we developed and provide initial validation for the P1vital® Affective Faces set (PAFs) as a contemporary alternative to the widely-used Pictures of Facial Affect (PoFA).

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Fluorescence microscopy and image analysis are powerful techniques to examine the distribution and interactions of different cellular compartments, including mammalian organelles with intravacuolar pathogens. Toxoplasma gondii is an obligate intracellular protozoan parasite that forms a membrane-bound compartment, the parasitophorous vacuole (PV), upon invasion of mammalian cells. From within the PV, the parasite interacts with many host organelles (without fusion), redirects host vesicles decorated with Rab GTPases to the PV, and internalizes many of these nutrient-filled Rab vesicles into the PV.

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Genetically attenuated sporozoite vaccines can elicit long-lasting protection against malaria but pose risks of breakthrough infection. Chemoprophylaxis vaccination (CVac) has proven to be the most effective vaccine strategy against malaria. Here, we demonstrate that a liver stage-specific autophagy mutant of Plasmodium berghei (ATG8 overexpressor), when used as a live vaccine under a CVac regimen, provides superior long-lasting protection, in both inbred and outbred mice, as compared to WT-CVac.

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Inorganic ions such as phosphate, are essential nutrients required for a broad spectrum of cellular functions and regulation. During infection, pathogens must obtain inorganic phosphate (Pi) from the host. Despite the essentiality of phosphate for all forms of life, how the intracellular parasite Toxoplasma gondii acquires Pi from the host cell is still unknown.

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Many intracellular microbial pathogens subvert, disrupt or otherwise modulate host membrane trafficking pathways to establish a successful infection. Among them, bacteria that are trapped in a phagosome during mammalian cell invasion, disengage the programmed degradation process by altering the identity of their replicative niche through the exclusion or recruitment of specific Rab GTPases to their vacuole. Many viruses co-opt essential cellular trafficking pathways to perform key steps in their lifecycles.

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Three-dimensional (3D) cell culture models bridge the gap between two-dimensional (2D) monolayer cultures and animal models. Physiologically relevant, 3D culture models have significantly advanced basic cell science and provide unique insights into host-pathogen interactions intrinsically linked to cell morphology. Toxoplasma gondii is an obligate intravacuolar parasite that chronically infects a large portion of the global human population.

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, an obligate intracellular parasite replicating in mammalian cells within a parasitophorous vacuole (PV), is an avid scavenger of lipids retrieved from the host cell. Following lipid uptake, this parasite stores excess lipids in lipid droplets (LD). Here, we examined the lipid storage capacities of upon supplementation of the culture medium with various fatty acids at physiological concentrations.

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Many intracellular pathogens subvert host membrane trafficking pathways to promote their replication. multiplies in a membrane-bound parasitophorous vacuole (PV) that interacts with mammalian host organelles and intercepts Golgi Rab vesicles to acquire sphingolipids. The mechanisms of host vesicle internalization and processing within the PV remain undefined.

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Toxoplasma is an obligate intracellular parasite that replicates in mammalian cells within a parasitophorous vacuole (PV) that does not fuse with any host organelles. One mechanism developed by the parasite for nutrient acquisition is the attraction of host organelles to the PV. Here, we examined the exploitation of host lipid droplets (LD), ubiquitous fat storage organelles, by Toxoplasma.

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To investigate the opinions of final-year Canadian physiotherapy students of cardiorespiratory physiotherapy (CRP) and the factors influencing their decision about whether to pursue a career in CRP. A cross-sectional online survey was completed by final-year Master of Science of Physical Therapy students from three of the largest English-speaking physiotherapy schools in Canada. A total of 120 students responded to the survey (overall response rate was 44%).

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Characterizing australopith pelvic morphology has been difficult in part because of limited fossilized pelvic material. Here, we reassess the morphology of an under-studied adult right ilium and pubis (Sts 65) from Member 4 of Sterkfontein, South Africa, and provide a hypothetical digital reconstruction of its overall pelvic morphology. The small size of the pelvis, presence of a preauricular sulcus, and shape of the sciatic notch allow us to agree with past interpretations that Sts 65 likely belonged to a female.

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The protozoan parasite Toxoplasma gondii develops within a parasitophorous vacuole (PV) in mammalian cells, where it scavenges cholesterol. When cholesterol is present in excess in its environment, the parasite expulses this lipid into the PV or esterifies it for storage in lipid bodies. Here, we characterized a unique T.

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Toxoplasma gondii possesses sets of dense granule proteins (GRAs) that either assemble at, or cross the parasitophorous vacuole membrane (PVM) and exhibit motifs resembling the HT/PEXEL previously identified in a repertoire of exported Plasmodium proteins. Within Plasmodium spp., cleavage of the HT/PEXEL motif by the endoplasmic reticulum-resident protease Plasmepsin V precedes trafficking to and export across the PVM of proteins involved in pathogenicity and host cell remodelling.

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Purpose: To determine whether individuals with chronic obstructive pulmonary disease (COPD) have decreased arm activity during daily life compared with healthy controls and explore the relationships between arm activity during daily life and arm functional measures in individuals with COPD.

Methods: This was a prospective cross-sectional study that included 30 people with COPD and 14 healthy controls. Subjects attended a single assessment session in which measurements of arm exercise capacity, arm functional performance, self-perception of performance during activities of daily living (ADL), shoulder and elbow flexion force and biceps and triceps thickness were performed.

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Rationale: In patients with chronic obstructive pulmonary disease (COPD), partitioned exercise training using one-legged cycling leads to greater improvements in peak oxygen uptake than conventional two-legged cycling.

Objectives: We evaluated the feasibility of incorporating one-legged cycling as the principal aerobic training modality for pulmonary rehabilitation in COPD.

Methods: Physiotherapists underwent four teaching sessions about the principles and practical implementation of one-legged cycling training.

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Background: We have recently demonstrated the efficacy of balance training in addition to Pulmonary Rehabilitation (PR) at improving measures of balance associated with an increased risk of falls in individuals with Chronic Obstructive Pulmonary Disease (COPD). Few knowledge translation (KT) projects have been conducted in rehabilitation settings. The goal of this study was to translate lessons learnt from efficacy studies of balance training into a sustainable clinical service.

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Toxoplasma gondii and Neospora caninum, which cause the diseases toxoplasmosis and neosporosis, respectively, are two closely related apicomplexan parasites. They have similar heteroxenous life cycles and conserved genomes and share many metabolic features. Despite these similarities, T.

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