56 results on '"Filgueira, Luis"'
Search Results
2. The legal and ethical framework governing body donation in Europe - 2nd update on current practice
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Brenner, Erich, Bleys, Ronald L A W, de Caro, Raffaele, Catereniuc, Ilia, Chirculescu, Andy R M, Destrieux, Christophe, Eppler, Elisabeth, Filgueira, Luis, Kachlik, David, Kiss, Péter, Lee, Clive, Matveeva, Niki, Natsis, Konstantinos, Pais, Diogo, Paulsen, Friedrich, Piagkou, Maria, Quondamatteo, Fabio, Reglődi, Dóra, Şendemir, Erdoğan, Tranum-Jensen, Jørgen, Tutkuviene, Janina, Vázquez Osorio, María Teresa, Brenner, Erich, Bleys, Ronald L A W, de Caro, Raffaele, Catereniuc, Ilia, Chirculescu, Andy R M, Destrieux, Christophe, Eppler, Elisabeth, Filgueira, Luis, Kachlik, David, Kiss, Péter, Lee, Clive, Matveeva, Niki, Natsis, Konstantinos, Pais, Diogo, Paulsen, Friedrich, Piagkou, Maria, Quondamatteo, Fabio, Reglődi, Dóra, Şendemir, Erdoğan, Tranum-Jensen, Jørgen, Tutkuviene, Janina, and Vázquez Osorio, María Teresa
- Abstract
BACKGROUND: In 2008, members of the TEPARG provided first insights into the legal and ethical framework governing body donation in Europe. In 2012, a first update followed. This paper is now the second update on this topic and tries to extend the available information to many more European countries.METHODS: For this second update, we have asked authors from all European countries to contribute their national perspectives. By this enquiry, we got many contributions compiled in this paper. When we did not get a personal contribution, one of us (EB) searched the internet for relevant information.RESULTS: Perspectives on the legal and ethical framework governing body donation in Europe.CONCLUSIONS: We still see that a clear and rigorous legal framework is still unavailable in several countries. We found national regulations in 18 out of 39 countries; two others have at least federal laws. Several countries accept not only donated bodies but also utilise unclaimed bodies. These findings can guide policymakers in reviewing and updating existing laws and regulations related to body donation and anatomical studies.
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- 2024
3. The legal and ethical framework governing body donation in Europe - 2nd update on current practice
- Author
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Brenner, Erich, Bleys, Ronald L A W, de Caro, Raffaele, Catereniuc, Ilia, Chirculescu, Andy R M, Destrieux, Christophe, Eppler, Elisabeth, Filgueira, Luis, Kachlik, David, Kiss, Péter, Lee, Clive, Matveeva, Niki, Natsis, Konstantinos, Pais, Diogo, Paulsen, Friedrich, Piagkou, Maria, Quondamatteo, Fabio, Reglődi, Dóra, Şendemir, Erdoğan, Tranum-Jensen, Jørgen, Tutkuviene, Janina, Vázquez Osorio, María Teresa, Brenner, Erich, Bleys, Ronald L A W, de Caro, Raffaele, Catereniuc, Ilia, Chirculescu, Andy R M, Destrieux, Christophe, Eppler, Elisabeth, Filgueira, Luis, Kachlik, David, Kiss, Péter, Lee, Clive, Matveeva, Niki, Natsis, Konstantinos, Pais, Diogo, Paulsen, Friedrich, Piagkou, Maria, Quondamatteo, Fabio, Reglődi, Dóra, Şendemir, Erdoğan, Tranum-Jensen, Jørgen, Tutkuviene, Janina, and Vázquez Osorio, María Teresa
- Abstract
BACKGROUND: In 2008, members of the TEPARG provided first insights into the legal and ethical framework governing body donation in Europe. In 2012, a first update followed. This paper is now the second update on this topic and tries to extend the available information to many more European countries.METHODS: For this second update, we have asked authors from all European countries to contribute their national perspectives. By this enquiry, we got many contributions compiled in this paper. When we did not get a personal contribution, one of us (EB) searched the internet for relevant information.RESULTS: Perspectives on the legal and ethical framework governing body donation in Europe.CONCLUSIONS: We still see that a clear and rigorous legal framework is still unavailable in several countries. We found national regulations in 18 out of 39 countries; two others have at least federal laws. Several countries accept not only donated bodies but also utilise unclaimed bodies. These findings can guide policymakers in reviewing and updating existing laws and regulations related to body donation and anatomical studies.
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- 2024
4. Innervation of the clavicular part of the deltoid muscle by the lateral pectoral nerve
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Larionov, Alexey; https://orcid.org/0000-0001-6902-8878, Yotovski, Peter, Link, Karl, Filgueira, Luis, Larionov, Alexey; https://orcid.org/0000-0001-6902-8878, Yotovski, Peter, Link, Karl, and Filgueira, Luis
- Abstract
INTRODUCTION: The innervation pattern of the clavicular head of the deltoid muscle and its corresponding topography were investigated via cadaveric dissection in the present study, focusing on the lateral pectoral nerve. MATERIALS AND METHODS: Fifty-eight upper extremities were dissected and the nerve supplies to the deltoid muscle and the variability of the lateral pectoral and axillary nerves, including their topographical patterns, were noted. RESULTS: The clavicular portion of the deltoid muscle received a deltoid branch from the lateral pectoral nerve in 86.2% of cases. Two topographical patterns of the lateral pectoral nerve were observed, depending on the branching level from the brachial plexus: a proximal variant, where the nerve entered the pectoral region undern the clavicle, and a distal variant, where the nerve entered the pectoral region from the axillary fossa around the caudal border of the pectoralis minor. These dissection findings were supported by histological confirmation of peripheral nerve tissue entering the clavicular part of the deltoid muscle. CONCLUSION: The topographical variations of the lateral pectoral nerve are relevant for orthopedic and trauma surgeons and neurologists. These new data could revise the interpretation of deltoid muscle atrophy and of thoracic outlet and pectoralis minor compression syndromes. They could also explain the residual anteversion function of the arm after axillary nerve injury and deficiency, which is often thought to be related to biceps brachii muscle function.
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- 2020
5. Anatomic analysis of the internal and external aspects of the pterion
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Uz, Aysun, Korkmaz, Ali Can, Filgueira, Luis, Guner, Mehmet Ali, Tubbs, Richard Shane, Demirciler, Ayse Karatas, Uz, Aysun, Korkmaz, Ali Can, Filgueira, Luis, Guner, Mehmet Ali, Tubbs, Richard Shane, and Demirciler, Ayse Karatas
- Abstract
Objective: The pterion is an H-shaped suture complex. This study's goal was to determine the location of its external and internal surfaces and extension and emphasize and discuss its surgical importance.Methods: Fifty dried adult human skulls were obtained from the Department of Anatomy. A 2-mm drill bit was placed externally over the pterion, and the pterion was drilled through the bone perpendicular to the skull's surface.Results: The midpoint of the H shape in the pterion area was not at the same level on the skull's external and internal pterion surfaces. According to these measurements, the external pterion lay above the internal pterion when the skull was viewed externally. Furthermore, the internal pterion was on average longer than the external pterion. The internal and external pterions were schematized such that the skull was viewed from the outside. These areas were divided into 4 quadrants (anterior-superior, anterior-inferior, posterior-superior, and posterior-inferior) by a vertical and horizontal line. In 30 cases (60%), sulci of the middle meningeal artery's parietal branches entered the posterior-superior quadrant on the bone, whereas the artery's frontal branches were located in the anterior-superior and anterior- inferior quadrants, and the Sylvian fissure's origin was in the posterior-inferior quadrant.Conclusions: By using a subdivision into 4 quadrants, and considering our anatomic findings, we determined the way surgical procedures can be performed more easily and reliably. Even with modern localization technologies, anatomic landmarks can be useful to the neurosurgeon.
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- 2020
6. Granzyme B attenuates bacterial virulence by targeting secreted factors
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López León, Diego, Matthey, Patricia, Fellay, Isabelle, Blanchard, Marianne, Martinvalet, Denis, Mantel, Pierre-Yves, Filgueira, Luis, Walch, Michael, López León, Diego, Matthey, Patricia, Fellay, Isabelle, Blanchard, Marianne, Martinvalet, Denis, Mantel, Pierre-Yves, Filgueira, Luis, and Walch, Michael
- Abstract
Pathogenic bacteria secrete virulence factors that interact with the human host to establish infections. The human immune system evolved multiple mechanisms to fight bacterial invaders, including immune proteases that were demonstrated to contribute crucially to antibacterial defense. Here we show that granzyme B degrades multiple secreted virulence mediators from Listeria monocytogenes, Salmonella typhimurium, and Mycobacteria tuberculosis. Pathogenic bacteria, when infected in the presence of granzyme B or granzyme-secreting killer cells, fail to grow in human macrophages and epithelial cells owing to their crippled virulence. A granzyme B-uncleavable mutant form of the major Listeria virulence factor, listeriolysin O, rescued the virulence defect in response to granzyme treatment. Hence, we link the degradation of a single factor with the observed decrease in virulent bacteria growth. Overall, we reveal here an innate immune barrier function of granzyme B by disrupting bacterial virulence to facilitate bacteria clearance by bystander immune and non-immune cells.
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- 2020
7. Human microglia respond to malaria-induced extracellular vesicles
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Mbagwu, Smart Ikechukwu, Lannes, Nils, Walch, Michael, Filgueira, Luis, Mantel, Pierre-Yves, Mbagwu, Smart Ikechukwu, Lannes, Nils, Walch, Michael, Filgueira, Luis, and Mantel, Pierre-Yves
- Abstract
Microglia are the chief immune cells of the brain and have been reported to be activated in severe malaria. Their activation may drive towards neuroinflammation in cerebral malaria. Malaria-infected red blood cell derived-extracellular vesicles (MiREVs) are produced during the blood stage of malaria infection. They mediate intercellular communication and immune regulation, among other functions. During cerebral malaria, the breakdown of the bloodbrain barrier can promote the migration of substances such as MiREVs from the periphery into the brain, targeting cells such as microglia. Microglia and extracellular vesicle interactions in different pathological conditions have been reported to induce neuroinflammation. Unlike in astrocytes, microgliaextracellular vesicle interaction has not yet been described in malaria infection. Therefore, in this study, we aimed to investigate the uptake of MiREVs by human microglia cells and their cytokine response. Human blood monocyte-derived microglia (MoMi) were generated from buffy coats of anonymous healthy donors using Ficoll-Paque density gradient centrifugation. The MiREVs were isolated from the Plasmodium falciparum cultures. They were purified by ultracentrifugation and labeled with PKH67 green fluorescent dye. The internalization of MiREVs by MoMi was observed after 4 h of co-incubation on coverslips placed in a 24-well plate at 37 C using confocal microscopy. Cytokine-gene expression was investigated using rt- qPCR, following the stimulation of the MoMi cells with supernatants from the parasite cultures at 2, 4, and 24 h, respectively. MiREVs were internalized by the microglia and accumulated in the perinuclear region. MiREVs-treated cells increased gene expression of the inflammatory cytokine TNF and reduced gene expression of the immune suppressive IL-10. Overall, the results indicate that MiREVs may act on microglia, which would contribute to enhanced inflammation in cerebral malaria.
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- 2020
8. Innervation of the clavicular part of the deltoid muscle by the lateral pectoral nerve
- Author
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Larionov, Alexey, Yotovski, Peter, Link, Karl, Filgueira, Luis, Larionov, Alexey, Yotovski, Peter, Link, Karl, and Filgueira, Luis
- Abstract
The innervation pattern of the clavicular head of the deltoid muscle and its corresponding topography was investigated via cadaveric dissection in the present study, focusing on the lateral pectoral nerve.Materials and methods: Fifty‐eight upper extremities were dissected and the nerve supplies to the deltoid muscle and the variability of the lateral pectoral and axillary nerves, including their topographical patterns, were noted.Results: The clavicular portion of the deltoid muscle received a deltoid branch from the lateral pectoral nerve in 86.2% of cases. Two topographical patterns of the lateral pectoral nerve were observed, depending on the branching level from the brachial plexus: a proximal variant, where the nerve entered the pectoral region under the clavicle, and a distal variant, where the nerve entered the pectoral region from the axillary fossa around the caudal border of the pectoralis minor. These dissection findings were supported by histological confirmation of peripheral nerve tissue entering the clavicular part of the deltoid muscle.Conclusions: The topographical variations of the lateral pectoral nerve are relevant for orthopedic and trauma surgeons and neurologists. These new data could revise the interpretation of deltoid muscle atrophy and of thoracic outlet and pectoralis minor compression syndromes. They could also explain the residual anteversion function of the arm after axillary nerve injury and deficiency, which is often thought to be related to biceps brachii muscle function.
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- 2020
9. Differential expression of CD31 and von Willebrand factor on endothelial cells in different regions of the human brain: potential implications for cerebral malaria pathogenesis
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Mbagwu, Smart Ikechukwu, Filgueira, Luis, Mbagwu, Smart Ikechukwu, and Filgueira, Luis
- Abstract
Cerebral microvascular endothelial cells (CMVECs) line the vascular system of the brain and are the chief cells in the formation and function of the blood brain barrier (BBB). These cells are heterogeneous along the cerebral vasculature and any dysfunctional state in these cells can result in a local loss of function of the BBB in any region of the brain. There is currently no report on the distribution and variation of the CMVECs in different brain regions in humans. This study investigated microcirculation in the adult human brain by the characterization of the expression pattern of brain endothelial cell markers in different brain regions. Five different brain regions consisting of the visual cortex, the hippocampus, the precentral gyrus, the postcentral gyrus, and the rhinal cortex obtained from three normal adult human brain specimens were studied and analyzed for the expression of the endothelial cell markers: cluster of differentiation 31 (CD31) and von-Willebrand-Factor (vWF) through immunohistochemistry. We observed differences in the expression pattern of CD31 and vWF between the gray matter and the white matter in the brain regions. Furthermore, there were also regional variations in the pattern of expression of the endothelial cell biomarkers. Thus, this suggests differences in the nature of vascularization in various regions of the human brain. These observations also suggest the existence of variation in structure and function of different brain regions, which could reflect in the pathophysiological outcomes in a diseased state.
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- 2020
10. A detailed review on the clinical anatomy of the pectoralis major muscle
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Larionov, Alexey, Yotovski, Peter, Filgueira, Luis, Larionov, Alexey, Yotovski, Peter, and Filgueira, Luis
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The pectoralis major is a muscle of the upper limb girdle. This muscle has a unique morphological architectonic and a high rate of clinical applications. However, there is lack of data regarding the morphological and functional interactions of the pectoralis major with other muscle and fascial compartments. According to the applied knowledge, the “Humero-pectoral” morpho-functional concept has been postulated. The purpose of this review was the dissectible investigation of the muscle anatomy and literature review of surgical applications.
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- 2019
11. Microglia at center stage: a comprehensive review about the versatile and unique residential macrophages of the central nervous system
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Lannes, Nils, Eppler, Elisabeth, Etemad, Samar, Yotovski, Peter, Filgueira, Luis, Lannes, Nils, Eppler, Elisabeth, Etemad, Samar, Yotovski, Peter, and Filgueira, Luis
- Abstract
Microglia cells are the unique residential macrophages of the central nervous system (CNS). They have a special origin, as they derive from the embryonic yolk sac and enter the developing CNS at a very early stage. They play an important role during CNS development and adult homeostasis. They have a major contribution to adult neurogenesis and neuroinflammation. Thus, they participate in the pathogenesis of neurodegenerative diseases and contribute to aging. They play an important role in sustaining and breaking the blood-brain barrier. As innate immune cells, they contribute substantially to the immune response against infectious agents affecting the CNS. They play also a major role in the growth of tumours of the CNS. Microglia are consequently the key cell population linking the nervous and the immune system. This review covers all different aspects of microglia biology and pathology in a comprehensive way.
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- 2019
12. Enhancing scientific communication skills: a real-world simulation in a tertiary-level life science class using e-learning technology in biomedical literature perception, reflective review writing on a clinical issue, and self and peer assessments
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Eppler, Elisabeth, Meyer, Jan, Serowy, Steffen, Link, Karl, Pauk, Barbara, Filgueira, Luis, Eppler, Elisabeth, Meyer, Jan, Serowy, Steffen, Link, Karl, Pauk, Barbara, and Filgueira, Luis
- Abstract
This educational study aimed to explore the feasibility and acceptance of a literacy exercise adopted from the realworld of scientific publishing in a cell and tissue biology course. For that purpose, a tertiary-level multimodality science course, which integrated a blended learning faculty and student lectures, journal club, and wet laboratory sessions including a research project as well as examinations, was complemented by essaywriting of a review and peerreviewing of five manuscripts. All tasks contributed to the final course mark. Special emphasis was laid on the usability of different E-Learning applications for scientific writing and teacher- and peerassessment procedures. Further, potential influences of student characteristics on their peerand self-assessments as well as their acceptance of the feedback from their peers were evaluated. Seventy-five undergraduate students from different Bachelor programs were included in the study. Plagiarism check and double-blind assessments of the essays were performed using “Turnitin.com.” Students self- assessed their paper and received feedback from five peers and the teacher. Peer assessment was more severe than the teacher- or self-assessment, and the peer mark correlated best with the final course mark. Students with better marks assessed more generously, and there had moderate tendencies for influences of gender and background on peer feedback behavior. The students perceived the writing and assessment exercises, especially being peer-assessed, as demanding, but rewarding and a great learning experience. The additional tasks were feasible using E-Learning technology, which should foster future biomedical courses to train writing skills and the ability to cope with different roles in the scientific community.
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- 2019
13. Evaluation of extracellular vesicle function during malaria infection
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Andrea Hernández-Castañeda, María, Mbagwu, Smart Ikechukwu, Babatunde, Kehinde Adebayo, Walch, Michael, Filgueira, Luis, Mantel, Pierre-Yves, Andrea Hernández-Castañeda, María, Mbagwu, Smart Ikechukwu, Babatunde, Kehinde Adebayo, Walch, Michael, Filgueira, Luis, and Mantel, Pierre-Yves
- Abstract
Malaria is a life-threatening disease caused by Plasmodium parasites, with P. falciparum being the most prevalent on the African continent and responsible for most malaria-related deaths globally. Several factors including parasite sequestration in tissues, vascular dysfunction, and inflammatory responses influence the evolution of the disease in malaria-infected people. P. falciparum-infected red blood cells (iRBCs) release small extracellular vesicles (EVs) containing different kinds of cargo molecules that mediate pathogenesis and cellular communication between parasites and host. EVs are efficiently taken up by cells in which they modulate their function. Here we discuss strategies to address the role of EVs in parasite-host interactions. First, we describe a straightforward method for labeling and tracking EV internalization by endothelial cells, using a green cell linker dye. Second, we report a simple way to measure permeability across an endothelial cell monolayer by using a fluorescently labeled dextran. Finally, we show how to investigate the role of small non-coding RNA molecules in endothelial cell function.
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- 2019
14. Review of emerging japanese encephalitis virus: new aspects and concepts about entry into the brain and inter-cellular spreading
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Filgueira, Luis, Lannes, Nils, Filgueira, Luis, and Lannes, Nils
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Japanese encephalitis virus (JEV) is an emerging flavivirus of the Asia-Pacific region. More than two billion people live in endemic or epidemic areas and are at risk of infection. Recently, the first autochthonous human case was recorded in Africa, and infected birds have been found in Europe. JEV may spread even further to other continents. The first section of this review covers established and new information about the epidemiology of JEV. The subsequent sections focus on the impact of JEV on humans, including the natural course and immunity. Furthermore, new concepts are discussed about JEVs entry into the brain. Finally, interactions of JEV and host cells are covered, as well as how JEV may spread in the body through latently infected immune cells and cell-to-cell transmission of virions or via other infectious material, including JEV genomic RNA.
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- 2019
15. CX 3 CR1-CX 3 CL1-dependent cell-to-cell Japanese encephalitis virus transmission by human microglial cells
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Lannes, Nils, Garcia-Nicolàs, Obdullio, Démoulins, Thomas, Summerfield, Artur, Filgueira, Luis, Lannes, Nils, Garcia-Nicolàs, Obdullio, Démoulins, Thomas, Summerfield, Artur, and Filgueira, Luis
- Abstract
The neurotropic Japanese encephalitis virus (JEV) is responsible for Japanese encephalitis, an uncontrolled inflammatory disease of the central nervous system. Microglia cells are the unique innate immune cell type populating the brain that cross- communicate with neurons via the CX3CR1-CX3CL1 axis. However, microglia may serve as a viral reservoir for JEV. Human microglia are able to transmit JEV infectivity to neighbouring cells in a cell-to-cell contact-dependent manner. Using JEV-treated human blood monocyte-derived microglia, the present study investigates molecular mechanisms behind cell-to-cell virus transmission by human microglia. For that purpose, JEV-associated microglia were co-cultured with JEV susceptible baby hamster kidney cells under various conditions. Here, we show that microglia hosting JEV for up to 10 days were able to transmit the virus to susceptible cells. Interestingly, neutralizing anti-JEV antibodies did not completely abrogate cell-to-cell virus transmission. Hence, intracellular viral RNA could be a contributing source of infectious virus material upon intercellular interactions. Importantly, the CX3CL1- CX3CR1 axis was a key regulator of cell-to-cell virus transmission from JEV-hosting human microglia. Our findings suggest that human microglia may be a source of infection for neuronal populations and sustain JEV brain pathogenesis in long-term infection. Moreover, the present work emphasizes on the critical role of the CX3CR1- CX3CL1 axis in JEV pathogenesis mediating transmission of infectious genomic JEV RNA.
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- 2019
16. Human dendritic cells process and present Listeria antigens for in vitro priming of autologous CD4+ T lymphocytes
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Eppler, Elisabeth, Walch, Michael, Latinovic-Golic, Sonja, Dumrese, Claudia, Filgueira, Luis, Groscurth, Peter, Eppler, Elisabeth, Walch, Michael, Latinovic-Golic, Sonja, Dumrese, Claudia, Filgueira, Luis, and Groscurth, Peter
- Abstract
The role of human dendritic cells (DC) in the immune response toward intracellularly growing Listeria was analyzed under in vitro conditions using several morphological and functional methods. DC incubated with Listeria innocua and L. monocytogenes, respectively, readily phagocytosed the bacteria. Listeria did not impair viability and immunogenic potential of human DC. Listerial antigens were found to be processed within the lysosomal compartment of DC and colocalized with major histocompatibility complex (MHC) class II molecules, as shown by fluorescence and transmission electron microscopy. DC challenged with apathogenic L. innocua were highly effective in priming autologous naïve T cells (mainly CD4+) in vitro. The T cells strongly proliferated in the presence of DC incubated with L. innocua, which could be significantly inhibited by anti-MHC II mAb. L. innocua-primed T cells were also successfully stimulated by DC harboring the pathogenic L. monocytogenes, either the wild-type strain EGD or the p60 reduced mutant strain RIII. From our results, we conclude that human DC infected with nonpathogenic intracellular bacteria are able to efficiently prime naïve T cells, which are then suitable for recognition of antigens derived from related virulent bacterial species. This in vitro human model provides an interesting tool for basic research in infectious immunology and possibly for a new immunotherapy
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- 2018
17. Silver-nanoparticles increase bactericidal activity and radical oxygen responses against bacterial pathogens in human osteoclasts
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Aurore, Valerie, Caldana, Fabienne, Blanchard, Marianne, Kharoubi Hess, Solange, Lannes, Nils, Mantel, Pierre-Yves, Filgueira, Luis, Walch, Michael, Aurore, Valerie, Caldana, Fabienne, Blanchard, Marianne, Kharoubi Hess, Solange, Lannes, Nils, Mantel, Pierre-Yves, Filgueira, Luis, and Walch, Michael
- Abstract
Bone infections are difficult to treat and can lead to severe tissue destruction. Acute bone infections are usually caused by Staphylococcus aureus. Osteoclasts, which belong to the monocyte/macrophage lineage, are the key cells in bone infections. They are not well equipped for killing bacteria and may serve as a reservoir for bacterial pathogens. Silver has been known for centuries for its bactericidal activity. Here, we investigated the bactericidal effects of nano-silver particles in bacteria infected human osteoclasts. We found that nano-silver in per se non-toxic concentration enhanced the bactericidal activity in osteoclasts against intracellular Methicillin-resistant, virulent Staphylococcus aureus. The reduced bacterial survival in nano-silver pretreated cells correlated with increased reactive oxygen responses towards the invading pathogens. Overall, these results indicate that nano-silver compounds should be considered as an effective treatment and prevention option for bacterial bone and orthopedic implant infections.
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- 2018
18. Regulation of inflammation in Japanese encephalitis
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Lannes, Nils, Summerfield, Artur, Filgueira, Luis, Lannes, Nils, Summerfield, Artur, and Filgueira, Luis
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Uncontrolled inflammatory response of the central nervous system is a hallmark of severe Japanese encephalitis (JE). Although inflammation is necessary to mount an efficient immune response against virus infections, exacerbated inflammatory response is often detrimental. In this context, cells of the monocytic lineage appear to be important forces driving JE pathogenesis.
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- 2018
19. The posterior ridge of the greater tuberosity of the humerus: a suitable landmark for the posterior approach to the shoulder joint?
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Grob, Karl, Monahan, Rebecca Helen, Manestar, Mirjana, Filgueira, Luis, Zdravkovic, Vilijam, Grob, Karl, Monahan, Rebecca Helen, Manestar, Mirjana, Filgueira, Luis, and Zdravkovic, Vilijam
- Abstract
The purpose of this study was to evaluate the posterior ridge of the greater tuberosity, a palpable prominence during surgery, as a landmark for the posterior approach to the glenohumeral joint.Methods: Twenty-five human cadaveric shoulders were dissected. In 5 cases, a full-thickness rotator cuff tear was present. The posterior surgical anatomy was defined, and the distance from the ridge to the interval between the infraspinatus (IS) and teres minor (TM) muscle, the distance from the ridge to the inferior border of the glenoid (IBG), and the distance between the IS-TM interval and the IBG were determined.Results: In all specimens, a prominent ridge on the posterior greater tuberosity lateral to the articular margin could be identified. The IS-TM interval was located, on average, 3 mm proximal to this ridge. The IS-TM interval corresponded to a point 5 mm proximal to the IBG. In all shoulders, the ridge was located, on average, 8 mm proximal to the IBG. The plane of the IS-TM interval showed a vertically oblique direction.Conclusion: The posterior ridge of the greater tuberosity is a suitable landmark to locate the internervous plane between the IS and TM and should not be crossed distally. Unlike other landmarks, the ridge moves with the humeral head, making it is less dependent on the patient's size, sex, and arm position and the quality of the rotator cuff. The ridge is always located proximal to the insertion of the TM and IBG.
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- 2018
20. Malaria infected red blood cells release small regulatory RNAs through extracellular vesicles
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Babatunde, Kehinde Adebayo, Mbagwu, Smart Ikechukwu, Hernández-Castañeda, María Andrea, Adapa, Swamy R., Walch, Michael, Filgueira, Luis, Falquet, Laurent, Jiang, Rays H. Y., Ghiran, Ionita, Mantel, Pierre-Yves, Babatunde, Kehinde Adebayo, Mbagwu, Smart Ikechukwu, Hernández-Castañeda, María Andrea, Adapa, Swamy R., Walch, Michael, Filgueira, Luis, Falquet, Laurent, Jiang, Rays H. Y., Ghiran, Ionita, and Mantel, Pierre-Yves
- Abstract
The parasite Plasmodium falciparum causes the most severe form of malaria. Cell communication between parasites is an important mechanism to control population density and differentiation. The infected red blood cells (iRBCs) release small extracellular vesicles (EVs) that transfer cargoes between cells. The EVs synchronize the differentiation of the asexual parasites into gametocytes to initiate the transmission to the mosquito. Beside their role in parasite communication, EVs regulate vascular function. So far, the exact cargoes responsible for cellular communication remain unknown. We isolated EVs from cultured iRBCs to determine their small RNA content. We identified several types of human and plasmodial regulatory RNAs. While the miRNAs and tRNA-derived fragments were the most abundant human RNAs, we also found Y-RNAs, vault RNAs, snoRNAs and piRNAs. Interestingly, we found about 120 plasmodial RNAs, including mRNAs coding for exported proteins and proteins involved in drug resistance, as well as non-coding RNAs, such as rRNAs, small nuclear (snRNAs) and tRNAs. These data show, that iRBC-EVs carry small regulatory RNAs. A role in cellular communication is possible since the RNAs were transferred to endothelial cells. Furthermore, the presence of Plasmodium RNAs, in EVs suggests that they may be used as biomarker to track and detect disease.
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- 2018
21. Experience from an optional dissection course in a clinically‐orientated concept to complement system‐based anatomy in a reformed curriculum
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Eppler, Elisabeth, Serowy, Steffen, Link, Karl, Filgueira, Luis, Eppler, Elisabeth, Serowy, Steffen, Link, Karl, and Filgueira, Luis
- Abstract
Profound anatomical knowledge is the basis for modern demands in medicine and surgery, but many countries worldwide including Australia and New Zealand have discontinued offering dissection courses to medical and dental students during the past decades. This educational project done in Australia aimed at enhancing basic and advanced anatomy teaching by engaging a sub-group of second-year undergraduate students of a compulsory prosection- and model-based anatomy course (n = 54/170) in an optional multimodal course, which should easily articulate with a vertical curriculum. With topographical cadaver dissections as core, peer student-teams prepared and peer-assessed anatomy lectures based on clinical topics, which were rated highly by the peers and teachers. Anatomical knowledge was tested by quizzes and a multiple-choice examination. Individual dissection skills were self- and teacher-assessed. A final course grade was assigned based on these assessments. The grades in the system-based compulsory course achieved by the attendees of the paralleling dissection course were compared with their peers attending other optional courses. After beginning of the semester, the students in the dissection course performed similar, significantly (P < 0.005) improved during the semester (78.5% vs. 69.9%, 70.1% vs. 64.1%), but in the integrated (including anatomy, biochemistry, physiology) final examination at the end of the year only tended to higher scores. As assessed through interviews and a voluntary questionnaire, all students of the optional dissection course liked these activities, which enhanced their learning experience. Thus, this concept elegantly integrates anatomical dissection with modern teaching demands and is feasible for implementation in modernized curricula.
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- 2018
22. Microglia at center stage: a comprehensive review about the versatile and unique residential macrophages of the central nervous system
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Lannes, Nils, Eppler, Elisabeth; https://orcid.org/0000-0002-8453-8312, Etemad, Samar, Yotovski, Peter, Filgueira, Luis; https://orcid.org/0000-0002-2266-6650, Lannes, Nils, Eppler, Elisabeth; https://orcid.org/0000-0002-8453-8312, Etemad, Samar, Yotovski, Peter, and Filgueira, Luis; https://orcid.org/0000-0002-2266-6650
- Abstract
Microglia cells are the unique residential macrophages of the central nervous system (CNS). They have a special origin, as they derive from the embryonic yolk sac and enter the developing CNS at a very early stage. They play an important role during CNS development and adult homeostasis. They have a major contribution to adult neurogenesis and neuroinflammation. Thus, they participate in the pathogenesis of neurodegenerative diseases and contribute to aging. They play an important role in sustaining and breaking the blood-brain barrier. As innate immune cells, they contribute substantially to the immune response against infectious agents affecting the CNS. They play also a major role in the growth of tumours of the CNS. Microglia are consequently the key cell population linking the nervous and the immune system. This review covers all different aspects of microglia biology and pathology in a comprehensive way.
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- 2017
23. Interactions of human microglia cells with Japanese encephalitis virus
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Lannes, Nils, Neuhaus, Viviane, Scolari, Brigitte, Kharoubi-Hess, Solange, Walch, Michael, Summerfield, Artur, Filgueira, Luis, Lannes, Nils, Neuhaus, Viviane, Scolari, Brigitte, Kharoubi-Hess, Solange, Walch, Michael, Summerfield, Artur, and Filgueira, Luis
- Abstract
Japanese encephalitis virus (JEV) is a neurotropic flavivirus causing mortality and morbidity in humans. Severe Japanese encephalitis cases display strong inflammatory responses in the central nervous system and an accumulation of viral particles in specific brain regions. Microglia cells are the unique brain-resident immune cell population with potent migratory functions and have been proposed to act as a viral reservoir for JEV. Animal models suggest that the targeting of microglia by JEV is partially responsible for inflammatory reactions in the brain. Nevertheless, the interactions between human microglia and JEV are poorly documented.Methods: Using human primary microglia and a new model of human blood monocyte-derived microglia, the present study explores the interaction between human microglia and JEV as well as the role of these cells in viral transmission to susceptible cells. To achieve this work, vaccine-containing inactivated JEV and two live JEV strains were applied on human microglia.Results: Live JEV was non-cytopathogenic to human microglia but increased levels of CCL2, CXCL9 and CXCL10 in such cultures. Furthermore, human microglia up-regulated the expression of the fraktalkine receptor CX3CR1 upon exposure to both JEV vaccine and live JEV. Although JEV vaccine enhanced MHC class II on all microglia, live JEV enhanced MHC class II mainly on CX3CR1+ microglia cells. Importantly, human microglia supported JEV replication, but infectivity was only transmitted to neighbouring cells in a contact-dependent manner.Conclusion: Our findings suggest that human microglia may be a source of neuronal infection and sustain JEV brain pathogenesis.
- Published
- 2017
24. The interaction between the vastus medialis and vastus intermedius and its influence on the extensor apparatus of the knee joint
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Grob, Karl, Manestar, Mirjana, Filgueira, Luis, Kuster, Markus S., Gilbey, Helen, Ackland, Timothy, Grob, Karl, Manestar, Mirjana, Filgueira, Luis, Kuster, Markus S., Gilbey, Helen, and Ackland, Timothy
- Abstract
Although the vastus medialis (VM) is closely associated with the vastus intermedius (VI), there is a lack of data regarding their functional relationship. The purpose of this study was to investigate the anatomical interaction between the VM and VI with regard to their origins, insertions, innervation and function within the extensor apparatus of the knee joint.Methods: Eighteen human cadaveric lower limbs were investigated using macro-dissection techniques. Six limbs were cut transversely in the middle third of the thigh. The mode of origin, insertion and nerve supply of the extensor apparatus of the knee joint were studied. The architecture of the VM and VI was examined in detail, as was their anatomical interaction and connective tissue linkage to the adjacent anatomical structures.Results: The VM originated medially from a broad hammock-like structure. The attachment site of the VM always spanned over a long distance between: (1) patella, (2) rectus femoris tendon and (3) aponeurosis of the VI, with the insertion into the VI being the largest. VM units were inserted twice—once on the anterior and once on the posterior side of the VI. The VI consists of a complex multi- layered structure. The layers of the medial VI aponeurosis fused with the aponeuroses of the tensor vastus intermedius and vastus lateralis. Together, they form the two- layered intermediate layer of the quadriceps tendon. The VM and medial parts of the VI were innervated by the same medial division of the femoral nerve.Conclusion: The VM consists of multiple muscle units inserting into the entire VI. Together, they build a potential functional muscular complex. Therefore, the VM acts as an indirect extensor of the knee joint regulating and adjusting the length of the extensor apparatus throughout the entire range of motion. It is of clinical importance that, besides the VM, substantial parts of the VI directly contribute to the medial pull on the patella and help to maintain medial tracking of th
- Published
- 2017
25. Influence of Vanadium 4+ and 5+ Ions on the Differentiation and Activation of Human Osteoclasts
- Author
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König, Matthias A; https://orcid.org/0000-0001-6376-3492, Gautschi, Oliver P, Simmen, Hans-Peter; https://orcid.org/0000-0001-6001-6344, Filgueira, Luis; https://orcid.org/0000-0002-2266-6650, Cadosch, Dieter; https://orcid.org/0000-0003-1328-923X, König, Matthias A; https://orcid.org/0000-0001-6376-3492, Gautschi, Oliver P, Simmen, Hans-Peter; https://orcid.org/0000-0001-6001-6344, Filgueira, Luis; https://orcid.org/0000-0002-2266-6650, and Cadosch, Dieter; https://orcid.org/0000-0003-1328-923X
- Published
- 2017
26. A newly discovered muscle: The tensor of the vastus intermedius
- Author
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Grob, Karl, Ackland, T., Kuster, M.S., Manestar, M., Filgueira, Luis, Grob, Karl, Ackland, T., Kuster, M.S., Manestar, M., and Filgueira, Luis
- Abstract
The quadriceps femoris is traditionally described as a muscle group composed of the rectus femoris and the three vasti. However, clinical experience and investigations of anatomical specimens are not consistent with the textbook description. We have found a second tensor-like muscle between the vastus lateralis (VL) and the vastus intermedius (VI), hereafter named the tensor VI (TVI). The aim of this study was to clarify whether this intervening muscle was a variation of the VL or the VI, or a separate head of the extensor apparatus. Twenty-six cadaveric lower limbs were investigated. The architecture of the quadriceps femoris was examined with special attention to innervation and vascularization patterns. All muscle components were traced from origin to insertion and their affiliations were determined. A TVI was found in all dissections. It was supplied by independent muscular and vascular branches of the femoral nerve and lateral circumflex femoral artery. Further distally, the TVI combined with an aponeurosis merging separately into the quadriceps tendon and inserting on the medial aspect of the patella. Four morphological types of TVI were distinguished: Independent-type (11/26), VI-type (6/26), VL-type (5/26), and Common-type (4/26). This study demonstrated that the quadriceps femoris is architecturally different from previous descriptions: there is an additional muscle belly between the VI and VL, which cannot be clearly assigned to the former or the latter. Distal exposure shows that this muscle belly becomes its own aponeurosis, which continues distally as part of the quadriceps tendon.
- Published
- 2016
27. Infected erythrocyte-derived extracellular vesicles alter vascular function via regulatory Ago2-miRNA complexes in malaria
- Author
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Mantel, Pierre-Yves, Hjelmqvist, Daisy, Walch, Michael, Kharoubi-Hess, Solange, Nilsson, Sandra, Ravel, Deepali, Ribeiro, Marina, Grüring, Christof, Ma, Siyuan, Padmanabhan, Prasad, Trachtenberg, Alexander, Ankarklev, ohan, Brancucci, Nicolas M., Huttenhower, Curtis, Duraisingh, Manoj T., Ghiran, Ionita, Kuo, Winston P., Filgueira, Luis, Martinelli, Roberta, Marti, Matthias, Mantel, Pierre-Yves, Hjelmqvist, Daisy, Walch, Michael, Kharoubi-Hess, Solange, Nilsson, Sandra, Ravel, Deepali, Ribeiro, Marina, Grüring, Christof, Ma, Siyuan, Padmanabhan, Prasad, Trachtenberg, Alexander, Ankarklev, ohan, Brancucci, Nicolas M., Huttenhower, Curtis, Duraisingh, Manoj T., Ghiran, Ionita, Kuo, Winston P., Filgueira, Luis, Martinelli, Roberta, and Marti, Matthias
- Abstract
Malaria remains one of the greatest public health challenges worldwide, particularly in sub-Saharan Africa. The clinical outcome of individuals infected with Plasmodium falciparum parasites depends on many factors including host systemic inflammatory responses, parasite sequestration in tissues and vascular dysfunction. Production of pro-inflammatory cytokines and chemokines promotes endothelial activation as well as recruitment and infiltration of inflammatory cells, which in turn triggers further endothelial cell activation and parasite sequestration. Inflammatory responses are triggered in part by bioactive parasite products such as hemozoin and infected red blood cell-derived extracellular vesicles (iRBC-derived EVs). Here we demonstrate that such EVs contain functional miRNA-Argonaute 2 complexes that are derived from the host RBC. Moreover, we show that EVs are efficiently internalized by endothelial cells, where the miRNA-Argonaute 2 complexes modulate target gene expression and barrier properties. Altogether, these findings provide a mechanistic link between EVs and vascular dysfunction during malaria infection.
- Published
- 2016
28. New insight in the architecture of the quadriceps tendon
- Author
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Grob, Karl, Manestar, Mirjana, Filgueira, Luis, Ackland, Timothy, Gilbey, Helen, Kuster, Markus S, Grob, Karl, Manestar, Mirjana, Filgueira, Luis, Ackland, Timothy, Gilbey, Helen, and Kuster, Markus S
- Published
- 2016
29. HDAC1/2-dependent P0 expression maintains paranodal and nodal integrity independently of myelin stability through interactions with neurofascins
- Author
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Brügger, Valérie, Engler, Stefanie, Pereira, Jorge A, Ruff, Sophie, Horn, Michael, Welzl, Hans, Münger, Emmanuelle, Vaquié, Adrien, Sidiropoulos, Páris N M, Egger, Boris, Yotovski, Peter, Filgueira, Luis, Somandin, Christian, Lühmann, Tessa C, D'Antonio, Maurizio, Yamaguchi, Teppei, Matthias, Patrick, Suter, Ueli, Jacob, Claire, Brügger, Valérie, Engler, Stefanie, Pereira, Jorge A, Ruff, Sophie, Horn, Michael, Welzl, Hans, Münger, Emmanuelle, Vaquié, Adrien, Sidiropoulos, Páris N M, Egger, Boris, Yotovski, Peter, Filgueira, Luis, Somandin, Christian, Lühmann, Tessa C, D'Antonio, Maurizio, Yamaguchi, Teppei, Matthias, Patrick, Suter, Ueli, and Jacob, Claire
- Abstract
The pathogenesis of peripheral neuropathies in adults is linked to maintenance mechanisms that are not well understood. Here, we elucidate a novel critical maintenance mechanism for Schwann cell (SC)-axon interaction. Using mouse genetics, ablation of the transcriptional regulators histone deacetylases 1 and 2 (HDAC1/2) in adult SCs severely affected paranodal and nodal integrity and led to demyelination/remyelination. Expression levels of the HDAC1/2 target gene myelin protein zero (P0) were reduced by half, accompanied by altered localization and stability of neurofascin (NFasc)155, NFasc186, and loss of Caspr and septate-like junctions. We identify P0 as a novel binding partner of NFasc155 and NFasc186, both in vivo and by in vitro adhesion assay. Furthermore, we demonstrate that HDAC1/2-dependent P0 expression is crucial for the maintenance of paranodal/nodal integrity and axonal function through interaction of P0 with neurofascins. In addition, we show that the latter mechanism is impaired by some P0 mutations that lead to late onset Charcot-Marie-Tooth disease.
- Published
- 2015
30. Breastmilk cell and fat contents respond similarly to removal of breastmilk by the infant
- Author
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Hassiotou, Foteini, Hepworth, Anna R., Williams, Tracey M., Twigger, Alecia-Jane, Perrella, Sharon, Lai, Ching Tat, Filgueira, Luis, Geddes, Donna T., Hartmann, Peter E., Hassiotou, Foteini, Hepworth, Anna R., Williams, Tracey M., Twigger, Alecia-Jane, Perrella, Sharon, Lai, Ching Tat, Filgueira, Luis, Geddes, Donna T., and Hartmann, Peter E.
- Abstract
Large inter- and intra-individual variations exist in breastmilk composition, yet factors associated with these variations in the short-term are not well understood. In this study, the effects of breastfeeding on breastmilk cellular and biochemical content were examined. Serial breastmilk samples (~5 mL) were collected from both breasts of breastfeeding women before and immediately after the first morning breastfeed, and then at 30-minute intervals for up to 3 hours post-feed on 2–4 mornings per participant. The infant fed from one breast only at each feed. Effects of pump versus hand expression for samples were evaluated. A consistent response pattern of breastmilk cell and fat contents to breastmilk removal was observed. Maximum fat and cell levels were obtained 30 minutes post-feed (P0.01), with up to 8-fold increase in fat and 12-fold increase in cell content compared to the pre-feed values, and then they gradually decreased. Breastmilk cell viability and protein concentration did not change with feeding (P>0.05), although large intra-individual variability was noted for protein. Expression mode for samples did not influence breastmilk composition (P>0.05). It is concluded that breastmilk fat content, and thus breast fullness, is closely associated with breastmilk cell content. This will now form the basis for standardization of sampling protocols in lactation studies and investigation of the mechanisms of milk synthesis and cell movement into breastmilk. Moreover, these findings generate new avenues for clinical interventions exploring growth and survival benefits conferred to preterm infants by providing the highest in fat and cells milk obtained at 30 min post-expression.
- Published
- 2014
31. Activation of dendritic cells by human papillomavirus-like particles through TLR4 and NF-kB-mediated signalling, moderated by TGF-B
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Liu, Xiaosong, Frazer, Ian H, Thomas, Ranjeny, Jabbar, Ibtissam A, Yan, Mengyong, Peng, Judy, Filgueira, Luis, Liu, Xiaosong, Frazer, Ian H, Thomas, Ranjeny, Jabbar, Ibtissam A, Yan, Mengyong, Peng, Judy, and Filgueira, Luis
- Abstract
Human papillomavirus-like particles (HPV-VLP) are a candidate vaccine for prevention of HPVinfection, and also are a candidate for an immunogenic delivery system for incorporated antigen. VLP activate in vitro generated dendritic cells (DC) but not Langerhans cells (LC); however, the mechanism of this activation is unknown. We have shown that uptake and activation of DC by VLP involves proteoglycan receptors and can be inhibited by heparin. Heparin has been shown to activate DC by signalling through Toll-like receptor 4 (TLR4) andnuclear factor (NF)-?B. The pathway of DC activation by VLP was further investigated in the present study. Exposure to VLP induced costimulatory molecule expression, RelB translocation and IL-10 production by DC but not by LC. The lack of LC activation was reversible when TGF-?was removed from the LC medium. VLP-induced induction of costimulatory molecule expression, RelB activation and cytokine secretion by DC was blocked by inhibition of NF-?B activation, heparin or TLR4 mAb. The data provide evidence that HPV-VLP signal DC througha pathway involving proteoglycan receptors, TLR4 and NF-?B, and shed light on the mechanism by which VLP stimulate immunity in the absence of adjuvants in vivo. LC may resist activation in normal epithelium abundant in TGF-?, but not in situations in which TGF-? concentrations are reduced.
- Published
- 2005
32. Activation of dendritic cells by human papillomavirus-like particles through TLR4 and NF-kB-mediated signalling, moderated by TGF-B
- Author
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Liu, Xiaosong, Frazer, Ian H, Thomas, Ranjeny, Jabbar, Ibtissam A, Yan, Mengyong, Peng, Judy, Filgueira, Luis, Liu, Xiaosong, Frazer, Ian H, Thomas, Ranjeny, Jabbar, Ibtissam A, Yan, Mengyong, Peng, Judy, and Filgueira, Luis
- Abstract
Human papillomavirus-like particles (HPV-VLP) are a candidate vaccine for prevention of HPVinfection, and also are a candidate for an immunogenic delivery system for incorporated antigen. VLP activate in vitro generated dendritic cells (DC) but not Langerhans cells (LC); however, the mechanism of this activation is unknown. We have shown that uptake and activation of DC by VLP involves proteoglycan receptors and can be inhibited by heparin. Heparin has been shown to activate DC by signalling through Toll-like receptor 4 (TLR4) andnuclear factor (NF)-?B. The pathway of DC activation by VLP was further investigated in the present study. Exposure to VLP induced costimulatory molecule expression, RelB translocation and IL-10 production by DC but not by LC. The lack of LC activation was reversible when TGF-?was removed from the LC medium. VLP-induced induction of costimulatory molecule expression, RelB activation and cytokine secretion by DC was blocked by inhibition of NF-?B activation, heparin or TLR4 mAb. The data provide evidence that HPV-VLP signal DC througha pathway involving proteoglycan receptors, TLR4 and NF-?B, and shed light on the mechanism by which VLP stimulate immunity in the absence of adjuvants in vivo. LC may resist activation in normal epithelium abundant in TGF-?, but not in situations in which TGF-? concentrations are reduced.
- Published
- 2005
33. Activation of dendritic cells by human papillomavirus-like particles through TLR4 and NF-kB-mediated signalling, moderated by TGF-B
- Author
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Liu, Xiaosong, Frazer, Ian H, Thomas, Ranjeny, Jabbar, Ibtissam A, Yan, Mengyong, Peng, Judy, Filgueira, Luis, Liu, Xiaosong, Frazer, Ian H, Thomas, Ranjeny, Jabbar, Ibtissam A, Yan, Mengyong, Peng, Judy, and Filgueira, Luis
- Abstract
Human papillomavirus-like particles (HPV-VLP) are a candidate vaccine for prevention of HPVinfection, and also are a candidate for an immunogenic delivery system for incorporated antigen. VLP activate in vitro generated dendritic cells (DC) but not Langerhans cells (LC); however, the mechanism of this activation is unknown. We have shown that uptake and activation of DC by VLP involves proteoglycan receptors and can be inhibited by heparin. Heparin has been shown to activate DC by signalling through Toll-like receptor 4 (TLR4) andnuclear factor (NF)-?B. The pathway of DC activation by VLP was further investigated in the present study. Exposure to VLP induced costimulatory molecule expression, RelB translocation and IL-10 production by DC but not by LC. The lack of LC activation was reversible when TGF-?was removed from the LC medium. VLP-induced induction of costimulatory molecule expression, RelB activation and cytokine secretion by DC was blocked by inhibition of NF-?B activation, heparin or TLR4 mAb. The data provide evidence that HPV-VLP signal DC througha pathway involving proteoglycan receptors, TLR4 and NF-?B, and shed light on the mechanism by which VLP stimulate immunity in the absence of adjuvants in vivo. LC may resist activation in normal epithelium abundant in TGF-?, but not in situations in which TGF-? concentrations are reduced.
- Published
- 2005
34. γδ T cells kill Plasmodium falciparum in a granzyme- and granulysin-dependent mechanism during the late blood stage
- Author
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Hernández-Castañeda, Maria Andrea, Happ, Katharina, Cattalani, Filippo, Wallimann, Alexandra, Blanchard, Marianne, Fellay, Isabelle, Scolari, Brigitte, Lannes, Nils, Mbagwu, Smart Ikechukwu, Fellay, Benoît, Filgueira, Luis, Mantel, Pierre-Yves, Walch, Michael, Hernández-Castañeda, Maria Andrea, Happ, Katharina, Cattalani, Filippo, Wallimann, Alexandra, Blanchard, Marianne, Fellay, Isabelle, Scolari, Brigitte, Lannes, Nils, Mbagwu, Smart Ikechukwu, Fellay, Benoît, Filgueira, Luis, Mantel, Pierre-Yves, and Walch, Michael
- Abstract
Plasmodium spp., the causative agent of malaria, have a complex life cycle. The exponential growth of the parasites during the blood stage is responsible for almost all malaria-associated morbidity and mortality. Therefore, tight immune control of the intraerythrocytic replication of the parasite is essential to prevent clinical malaria. Despite evidence that the particular lymphocyte subset of γδ T cells contributes to protective immunity during the blood stage in naive hosts, their precise inhibitory mechanisms remain unclear. Using human PBMCs, we confirmed in this study that γδ T cells specifically and massively expanded upon activation with Plasmodium falciparum culture supernatant. We also demonstrate that these activated cells gain cytolytic potential by upregulating cytotoxic effector proteins and IFN-γ. The killer cells bound to infected RBCs and killed intracellular P. falciparum via the transfer of the granzymes, which was mediated by granulysin in a stage-specific manner. Several vital plasmodial proteins were efficiently destroyed by granzyme B, suggesting proteolytic degradation of these proteins as essential in the lymphocyte-mediated death pathway. Overall, these data establish a granzyme- and granulysin-mediated innate immune mechanism exerted by γδ T cells to kill late-stage blood-residing P. falciparum.
35. Granzyme B attenuates bacterial virulence by targeting secreted factors
- Author
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López León, Diego, Matthey, Patricia, Fellay, Isabelle, Blanchard, Marianne, Martinvalet, Denis, Mantel, Pierre-Yves, Filgueira, Luis, Walch, Michael, López León, Diego, Matthey, Patricia, Fellay, Isabelle, Blanchard, Marianne, Martinvalet, Denis, Mantel, Pierre-Yves, Filgueira, Luis, and Walch, Michael
- Abstract
Pathogenic bacteria secrete virulence factors that interact with the human host to establish infections. The human immune system evolved multiple mechanisms to fight bacterial invaders, including immune proteases that were demonstrated to contribute crucially to antibacterial defense. Here we show that granzyme B degrades multiple secreted virulence mediators from Listeria monocytogenes, Salmonella typhimurium, and Mycobacteria tuberculosis. Pathogenic bacteria, when infected in the presence of granzyme B or granzyme-secreting killer cells, fail to grow in human macrophages and epithelial cells owing to their crippled virulence. A granzyme B-uncleavable mutant form of the major Listeria virulence factor, listeriolysin O, rescued the virulence defect in response to granzyme treatment. Hence, we link the degradation of a single factor with the observed decrease in virulent bacteria growth. Overall, we reveal here an innate immune barrier function of granzyme B by disrupting bacterial virulence to facilitate bacteria clearance by bystander immune and non-immune cells.
36. Anatomic analysis of the internal and external aspects of the pterion
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Uz, Aysun, Korkmaz, Ali Can, Filgueira, Luis, Guner, Mehmet Ali, Tubbs, Richard Shane, Demirciler, Ayse Karatas, Uz, Aysun, Korkmaz, Ali Can, Filgueira, Luis, Guner, Mehmet Ali, Tubbs, Richard Shane, and Demirciler, Ayse Karatas
- Abstract
Objective: The pterion is an H-shaped suture complex. This study's goal was to determine the location of its external and internal surfaces and extension and emphasize and discuss its surgical importance.Methods: Fifty dried adult human skulls were obtained from the Department of Anatomy. A 2-mm drill bit was placed externally over the pterion, and the pterion was drilled through the bone perpendicular to the skull's surface.Results: The midpoint of the H shape in the pterion area was not at the same level on the skull's external and internal pterion surfaces. According to these measurements, the external pterion lay above the internal pterion when the skull was viewed externally. Furthermore, the internal pterion was on average longer than the external pterion. The internal and external pterions were schematized such that the skull was viewed from the outside. These areas were divided into 4 quadrants (anterior-superior, anterior-inferior, posterior-superior, and posterior-inferior) by a vertical and horizontal line. In 30 cases (60%), sulci of the middle meningeal artery's parietal branches entered the posterior-superior quadrant on the bone, whereas the artery's frontal branches were located in the anterior-superior and anterior- inferior quadrants, and the Sylvian fissure's origin was in the posterior-inferior quadrant.Conclusions: By using a subdivision into 4 quadrants, and considering our anatomic findings, we determined the way surgical procedures can be performed more easily and reliably. Even with modern localization technologies, anatomic landmarks can be useful to the neurosurgeon.
37. Differential expression of CD31 and von Willebrand factor on endothelial cells in different regions of the human brain: potential implications for cerebral malaria pathogenesis
- Author
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Mbagwu, Smart Ikechukwu, Filgueira, Luis, Mbagwu, Smart Ikechukwu, and Filgueira, Luis
- Abstract
Cerebral microvascular endothelial cells (CMVECs) line the vascular system of the brain and are the chief cells in the formation and function of the blood brain barrier (BBB). These cells are heterogeneous along the cerebral vasculature and any dysfunctional state in these cells can result in a local loss of function of the BBB in any region of the brain. There is currently no report on the distribution and variation of the CMVECs in different brain regions in humans. This study investigated microcirculation in the adult human brain by the characterization of the expression pattern of brain endothelial cell markers in different brain regions. Five different brain regions consisting of the visual cortex, the hippocampus, the precentral gyrus, the postcentral gyrus, and the rhinal cortex obtained from three normal adult human brain specimens were studied and analyzed for the expression of the endothelial cell markers: cluster of differentiation 31 (CD31) and von-Willebrand-Factor (vWF) through immunohistochemistry. We observed differences in the expression pattern of CD31 and vWF between the gray matter and the white matter in the brain regions. Furthermore, there were also regional variations in the pattern of expression of the endothelial cell biomarkers. Thus, this suggests differences in the nature of vascularization in various regions of the human brain. These observations also suggest the existence of variation in structure and function of different brain regions, which could reflect in the pathophysiological outcomes in a diseased state.
38. Human microglia respond to malaria-induced extracellular vesicles
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Mbagwu, Smart Ikechukwu, Lannes, Nils, Walch, Michael, Filgueira, Luis, Mantel, Pierre-Yves, Mbagwu, Smart Ikechukwu, Lannes, Nils, Walch, Michael, Filgueira, Luis, and Mantel, Pierre-Yves
- Abstract
Microglia are the chief immune cells of the brain and have been reported to be activated in severe malaria. Their activation may drive towards neuroinflammation in cerebral malaria. Malaria-infected red blood cell derived-extracellular vesicles (MiREVs) are produced during the blood stage of malaria infection. They mediate intercellular communication and immune regulation, among other functions. During cerebral malaria, the breakdown of the bloodbrain barrier can promote the migration of substances such as MiREVs from the periphery into the brain, targeting cells such as microglia. Microglia and extracellular vesicle interactions in different pathological conditions have been reported to induce neuroinflammation. Unlike in astrocytes, microgliaextracellular vesicle interaction has not yet been described in malaria infection. Therefore, in this study, we aimed to investigate the uptake of MiREVs by human microglia cells and their cytokine response. Human blood monocyte-derived microglia (MoMi) were generated from buffy coats of anonymous healthy donors using Ficoll-Paque density gradient centrifugation. The MiREVs were isolated from the Plasmodium falciparum cultures. They were purified by ultracentrifugation and labeled with PKH67 green fluorescent dye. The internalization of MiREVs by MoMi was observed after 4 h of co-incubation on coverslips placed in a 24-well plate at 37 C using confocal microscopy. Cytokine-gene expression was investigated using rt- qPCR, following the stimulation of the MoMi cells with supernatants from the parasite cultures at 2, 4, and 24 h, respectively. MiREVs were internalized by the microglia and accumulated in the perinuclear region. MiREVs-treated cells increased gene expression of the inflammatory cytokine TNF and reduced gene expression of the immune suppressive IL-10. Overall, the results indicate that MiREVs may act on microglia, which would contribute to enhanced inflammation in cerebral malaria.
39. Innervation of the clavicular part of the deltoid muscle by the lateral pectoral nerve
- Author
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Larionov, Alexey, Yotovski, Peter, Link, Karl, Filgueira, Luis, Larionov, Alexey, Yotovski, Peter, Link, Karl, and Filgueira, Luis
- Abstract
The innervation pattern of the clavicular head of the deltoid muscle and its corresponding topography was investigated via cadaveric dissection in the present study, focusing on the lateral pectoral nerve.Materials and methods: Fifty‐eight upper extremities were dissected and the nerve supplies to the deltoid muscle and the variability of the lateral pectoral and axillary nerves, including their topographical patterns, were noted.Results: The clavicular portion of the deltoid muscle received a deltoid branch from the lateral pectoral nerve in 86.2% of cases. Two topographical patterns of the lateral pectoral nerve were observed, depending on the branching level from the brachial plexus: a proximal variant, where the nerve entered the pectoral region under the clavicle, and a distal variant, where the nerve entered the pectoral region from the axillary fossa around the caudal border of the pectoralis minor. These dissection findings were supported by histological confirmation of peripheral nerve tissue entering the clavicular part of the deltoid muscle.Conclusions: The topographical variations of the lateral pectoral nerve are relevant for orthopedic and trauma surgeons and neurologists. These new data could revise the interpretation of deltoid muscle atrophy and of thoracic outlet and pectoralis minor compression syndromes. They could also explain the residual anteversion function of the arm after axillary nerve injury and deficiency, which is often thought to be related to biceps brachii muscle function.
40. Review of emerging japanese encephalitis virus: new aspects and concepts about entry into the brain and inter-cellular spreading
- Author
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Filgueira, Luis, Lannes, Nils, Filgueira, Luis, and Lannes, Nils
- Abstract
Japanese encephalitis virus (JEV) is an emerging flavivirus of the Asia-Pacific region. More than two billion people live in endemic or epidemic areas and are at risk of infection. Recently, the first autochthonous human case was recorded in Africa, and infected birds have been found in Europe. JEV may spread even further to other continents. The first section of this review covers established and new information about the epidemiology of JEV. The subsequent sections focus on the impact of JEV on humans, including the natural course and immunity. Furthermore, new concepts are discussed about JEVs entry into the brain. Finally, interactions of JEV and host cells are covered, as well as how JEV may spread in the body through latently infected immune cells and cell-to-cell transmission of virions or via other infectious material, including JEV genomic RNA.
41. CX 3 CR1-CX 3 CL1-dependent cell-to-cell Japanese encephalitis virus transmission by human microglial cells
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Lannes, Nils, Garcia-Nicolàs, Obdullio, Démoulins, Thomas, Summerfield, Artur, Filgueira, Luis, Lannes, Nils, Garcia-Nicolàs, Obdullio, Démoulins, Thomas, Summerfield, Artur, and Filgueira, Luis
- Abstract
The neurotropic Japanese encephalitis virus (JEV) is responsible for Japanese encephalitis, an uncontrolled inflammatory disease of the central nervous system. Microglia cells are the unique innate immune cell type populating the brain that cross- communicate with neurons via the CX3CR1-CX3CL1 axis. However, microglia may serve as a viral reservoir for JEV. Human microglia are able to transmit JEV infectivity to neighbouring cells in a cell-to-cell contact-dependent manner. Using JEV-treated human blood monocyte-derived microglia, the present study investigates molecular mechanisms behind cell-to-cell virus transmission by human microglia. For that purpose, JEV-associated microglia were co-cultured with JEV susceptible baby hamster kidney cells under various conditions. Here, we show that microglia hosting JEV for up to 10 days were able to transmit the virus to susceptible cells. Interestingly, neutralizing anti-JEV antibodies did not completely abrogate cell-to-cell virus transmission. Hence, intracellular viral RNA could be a contributing source of infectious virus material upon intercellular interactions. Importantly, the CX3CL1- CX3CR1 axis was a key regulator of cell-to-cell virus transmission from JEV-hosting human microglia. Our findings suggest that human microglia may be a source of infection for neuronal populations and sustain JEV brain pathogenesis in long-term infection. Moreover, the present work emphasizes on the critical role of the CX3CR1- CX3CL1 axis in JEV pathogenesis mediating transmission of infectious genomic JEV RNA.
42. Infected erythrocyte-derived extracellular vesicles alter vascular function via regulatory Ago2-miRNA complexes in malaria
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Mantel, Pierre-Yves, Hjelmqvist, Daisy, Walch, Michael, Kharoubi-Hess, Solange, Nilsson, Sandra, Ravel, Deepali, Ribeiro, Marina, Grüring, Christof, Ma, Siyuan, Padmanabhan, Prasad, Trachtenberg, Alexander, Ankarklev, ohan, Brancucci, Nicolas M., Huttenhower, Curtis, Duraisingh, Manoj T., Ghiran, Ionita, Kuo, Winston P., Filgueira, Luis, Martinelli, Roberta, Marti, Matthias, Mantel, Pierre-Yves, Hjelmqvist, Daisy, Walch, Michael, Kharoubi-Hess, Solange, Nilsson, Sandra, Ravel, Deepali, Ribeiro, Marina, Grüring, Christof, Ma, Siyuan, Padmanabhan, Prasad, Trachtenberg, Alexander, Ankarklev, ohan, Brancucci, Nicolas M., Huttenhower, Curtis, Duraisingh, Manoj T., Ghiran, Ionita, Kuo, Winston P., Filgueira, Luis, Martinelli, Roberta, and Marti, Matthias
- Abstract
Malaria remains one of the greatest public health challenges worldwide, particularly in sub-Saharan Africa. The clinical outcome of individuals infected with Plasmodium falciparum parasites depends on many factors including host systemic inflammatory responses, parasite sequestration in tissues and vascular dysfunction. Production of pro-inflammatory cytokines and chemokines promotes endothelial activation as well as recruitment and infiltration of inflammatory cells, which in turn triggers further endothelial cell activation and parasite sequestration. Inflammatory responses are triggered in part by bioactive parasite products such as hemozoin and infected red blood cell-derived extracellular vesicles (iRBC-derived EVs). Here we demonstrate that such EVs contain functional miRNA-Argonaute 2 complexes that are derived from the host RBC. Moreover, we show that EVs are efficiently internalized by endothelial cells, where the miRNA-Argonaute 2 complexes modulate target gene expression and barrier properties. Altogether, these findings provide a mechanistic link between EVs and vascular dysfunction during malaria infection.
43. Breastmilk cell and fat contents respond similarly to removal of breastmilk by the infant
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Hassiotou, Foteini, Hepworth, Anna R., Williams, Tracey M., Twigger, Alecia-Jane, Perrella, Sharon, Lai, Ching Tat, Filgueira, Luis, Geddes, Donna T., Hartmann, Peter E., Hassiotou, Foteini, Hepworth, Anna R., Williams, Tracey M., Twigger, Alecia-Jane, Perrella, Sharon, Lai, Ching Tat, Filgueira, Luis, Geddes, Donna T., and Hartmann, Peter E.
- Abstract
Large inter- and intra-individual variations exist in breastmilk composition, yet factors associated with these variations in the short-term are not well understood. In this study, the effects of breastfeeding on breastmilk cellular and biochemical content were examined. Serial breastmilk samples (~5 mL) were collected from both breasts of breastfeeding women before and immediately after the first morning breastfeed, and then at 30-minute intervals for up to 3 hours post-feed on 2–4 mornings per participant. The infant fed from one breast only at each feed. Effects of pump versus hand expression for samples were evaluated. A consistent response pattern of breastmilk cell and fat contents to breastmilk removal was observed. Maximum fat and cell levels were obtained 30 minutes post-feed (P0.01), with up to 8-fold increase in fat and 12-fold increase in cell content compared to the pre-feed values, and then they gradually decreased. Breastmilk cell viability and protein concentration did not change with feeding (P>0.05), although large intra-individual variability was noted for protein. Expression mode for samples did not influence breastmilk composition (P>0.05). It is concluded that breastmilk fat content, and thus breast fullness, is closely associated with breastmilk cell content. This will now form the basis for standardization of sampling protocols in lactation studies and investigation of the mechanisms of milk synthesis and cell movement into breastmilk. Moreover, these findings generate new avenues for clinical interventions exploring growth and survival benefits conferred to preterm infants by providing the highest in fat and cells milk obtained at 30 min post-expression.
44. Evaluation of extracellular vesicle function during malaria infection
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Andrea Hernández-Castañeda, María, Mbagwu, Smart Ikechukwu, Babatunde, Kehinde Adebayo, Walch, Michael, Filgueira, Luis, Mantel, Pierre-Yves, Andrea Hernández-Castañeda, María, Mbagwu, Smart Ikechukwu, Babatunde, Kehinde Adebayo, Walch, Michael, Filgueira, Luis, and Mantel, Pierre-Yves
- Abstract
Malaria is a life-threatening disease caused by Plasmodium parasites, with P. falciparum being the most prevalent on the African continent and responsible for most malaria-related deaths globally. Several factors including parasite sequestration in tissues, vascular dysfunction, and inflammatory responses influence the evolution of the disease in malaria-infected people. P. falciparum-infected red blood cells (iRBCs) release small extracellular vesicles (EVs) containing different kinds of cargo molecules that mediate pathogenesis and cellular communication between parasites and host. EVs are efficiently taken up by cells in which they modulate their function. Here we discuss strategies to address the role of EVs in parasite-host interactions. First, we describe a straightforward method for labeling and tracking EV internalization by endothelial cells, using a green cell linker dye. Second, we report a simple way to measure permeability across an endothelial cell monolayer by using a fluorescently labeled dextran. Finally, we show how to investigate the role of small non-coding RNA molecules in endothelial cell function.
45. A detailed review on the clinical anatomy of the pectoralis major muscle
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Larionov, Alexey, Yotovski, Peter, Filgueira, Luis, Larionov, Alexey, Yotovski, Peter, and Filgueira, Luis
- Abstract
The pectoralis major is a muscle of the upper limb girdle. This muscle has a unique morphological architectonic and a high rate of clinical applications. However, there is lack of data regarding the morphological and functional interactions of the pectoralis major with other muscle and fascial compartments. According to the applied knowledge, the “Humero-pectoral” morpho-functional concept has been postulated. The purpose of this review was the dissectible investigation of the muscle anatomy and literature review of surgical applications.
46. Microglia at center stage: a comprehensive review about the versatile and unique residential macrophages of the central nervous system
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Lannes, Nils, Eppler, Elisabeth, Etemad, Samar, Yotovski, Peter, Filgueira, Luis, Lannes, Nils, Eppler, Elisabeth, Etemad, Samar, Yotovski, Peter, and Filgueira, Luis
- Abstract
Microglia cells are the unique residential macrophages of the central nervous system (CNS). They have a special origin, as they derive from the embryonic yolk sac and enter the developing CNS at a very early stage. They play an important role during CNS development and adult homeostasis. They have a major contribution to adult neurogenesis and neuroinflammation. Thus, they participate in the pathogenesis of neurodegenerative diseases and contribute to aging. They play an important role in sustaining and breaking the blood-brain barrier. As innate immune cells, they contribute substantially to the immune response against infectious agents affecting the CNS. They play also a major role in the growth of tumours of the CNS. Microglia are consequently the key cell population linking the nervous and the immune system. This review covers all different aspects of microglia biology and pathology in a comprehensive way.
47. Enhancing scientific communication skills: a real-world simulation in a tertiary-level life science class using e-learning technology in biomedical literature perception, reflective review writing on a clinical issue, and self and peer assessments
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Eppler, Elisabeth, Meyer, Jan, Serowy, Steffen, Link, Karl, Pauk, Barbara, Filgueira, Luis, Eppler, Elisabeth, Meyer, Jan, Serowy, Steffen, Link, Karl, Pauk, Barbara, and Filgueira, Luis
- Abstract
This educational study aimed to explore the feasibility and acceptance of a literacy exercise adopted from the realworld of scientific publishing in a cell and tissue biology course. For that purpose, a tertiary-level multimodality science course, which integrated a blended learning faculty and student lectures, journal club, and wet laboratory sessions including a research project as well as examinations, was complemented by essaywriting of a review and peerreviewing of five manuscripts. All tasks contributed to the final course mark. Special emphasis was laid on the usability of different E-Learning applications for scientific writing and teacher- and peerassessment procedures. Further, potential influences of student characteristics on their peerand self-assessments as well as their acceptance of the feedback from their peers were evaluated. Seventy-five undergraduate students from different Bachelor programs were included in the study. Plagiarism check and double-blind assessments of the essays were performed using “Turnitin.com.” Students self- assessed their paper and received feedback from five peers and the teacher. Peer assessment was more severe than the teacher- or self-assessment, and the peer mark correlated best with the final course mark. Students with better marks assessed more generously, and there had moderate tendencies for influences of gender and background on peer feedback behavior. The students perceived the writing and assessment exercises, especially being peer-assessed, as demanding, but rewarding and a great learning experience. The additional tasks were feasible using E-Learning technology, which should foster future biomedical courses to train writing skills and the ability to cope with different roles in the scientific community.
48. Human dendritic cells process and present Listeria antigens for in vitro priming of autologous CD4+ T lymphocytes
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Eppler, Elisabeth, Walch, Michael, Latinovic-Golic, Sonja, Dumrese, Claudia, Filgueira, Luis, Groscurth, Peter, Eppler, Elisabeth, Walch, Michael, Latinovic-Golic, Sonja, Dumrese, Claudia, Filgueira, Luis, and Groscurth, Peter
- Abstract
The role of human dendritic cells (DC) in the immune response toward intracellularly growing Listeria was analyzed under in vitro conditions using several morphological and functional methods. DC incubated with Listeria innocua and L. monocytogenes, respectively, readily phagocytosed the bacteria. Listeria did not impair viability and immunogenic potential of human DC. Listerial antigens were found to be processed within the lysosomal compartment of DC and colocalized with major histocompatibility complex (MHC) class II molecules, as shown by fluorescence and transmission electron microscopy. DC challenged with apathogenic L. innocua were highly effective in priming autologous naïve T cells (mainly CD4+) in vitro. The T cells strongly proliferated in the presence of DC incubated with L. innocua, which could be significantly inhibited by anti-MHC II mAb. L. innocua-primed T cells were also successfully stimulated by DC harboring the pathogenic L. monocytogenes, either the wild-type strain EGD or the p60 reduced mutant strain RIII. From our results, we conclude that human DC infected with nonpathogenic intracellular bacteria are able to efficiently prime naïve T cells, which are then suitable for recognition of antigens derived from related virulent bacterial species. This in vitro human model provides an interesting tool for basic research in infectious immunology and possibly for a new immunotherapy
49. Regulation of inflammation in Japanese encephalitis
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Lannes, Nils, Summerfield, Artur, Filgueira, Luis, Lannes, Nils, Summerfield, Artur, and Filgueira, Luis
- Abstract
Uncontrolled inflammatory response of the central nervous system is a hallmark of severe Japanese encephalitis (JE). Although inflammation is necessary to mount an efficient immune response against virus infections, exacerbated inflammatory response is often detrimental. In this context, cells of the monocytic lineage appear to be important forces driving JE pathogenesis.
50. Interactions of human microglia cells with Japanese encephalitis virus
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Lannes, Nils, Neuhaus, Viviane, Scolari, Brigitte, Kharoubi-Hess, Solange, Walch, Michael, Summerfield, Artur, Filgueira, Luis, Lannes, Nils, Neuhaus, Viviane, Scolari, Brigitte, Kharoubi-Hess, Solange, Walch, Michael, Summerfield, Artur, and Filgueira, Luis
- Abstract
Japanese encephalitis virus (JEV) is a neurotropic flavivirus causing mortality and morbidity in humans. Severe Japanese encephalitis cases display strong inflammatory responses in the central nervous system and an accumulation of viral particles in specific brain regions. Microglia cells are the unique brain-resident immune cell population with potent migratory functions and have been proposed to act as a viral reservoir for JEV. Animal models suggest that the targeting of microglia by JEV is partially responsible for inflammatory reactions in the brain. Nevertheless, the interactions between human microglia and JEV are poorly documented.Methods: Using human primary microglia and a new model of human blood monocyte-derived microglia, the present study explores the interaction between human microglia and JEV as well as the role of these cells in viral transmission to susceptible cells. To achieve this work, vaccine-containing inactivated JEV and two live JEV strains were applied on human microglia.Results: Live JEV was non-cytopathogenic to human microglia but increased levels of CCL2, CXCL9 and CXCL10 in such cultures. Furthermore, human microglia up-regulated the expression of the fraktalkine receptor CX3CR1 upon exposure to both JEV vaccine and live JEV. Although JEV vaccine enhanced MHC class II on all microglia, live JEV enhanced MHC class II mainly on CX3CR1+ microglia cells. Importantly, human microglia supported JEV replication, but infectivity was only transmitted to neighbouring cells in a contact-dependent manner.Conclusion: Our findings suggest that human microglia may be a source of neuronal infection and sustain JEV brain pathogenesis.
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