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2.
Adv Healthc Mater ; 9(16): e2000655, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32548967

RESUMO

There is an increasing interest in intraperitoneal delivery of chemotherapy as an aerosol in patients with peritoneal metastasis. The currently used technology is hampered by inhomogenous drug delivery throughout the peritoneal cavity because of gravity, drag, and inertial impaction. Addition of an electrical force to aerosol particles, exerted by an electrostatic field, can improve spatial aerosol homogeneity and enhance tissue penetration. A computational fluid dynamics model shows that electrostatic precipitation (EP) results in a significantly improved aerosol distribution. Fluorescent nanoparticles (NPs) remain stable after nebulization in vitro, while EP significantly improves spatial homogeneity of NP distribution. Next, pressurized intraperitoneal chemotherapy with and without EP using NP albumin bound paclitaxel (Nab-PTX) in a novel rat model is examined. EP does not worsen the effects of CO2 insufflation and intraperitoneal Nab-PTX on mesothelial structural integrity or the severity of peritoneal inflammation. Importantly, EP significantly enhances tissue penetration of Nab-PTX in the anatomical regions not facing the nozzle of the nebulizer. Also, the addition of EP leads to more homogenous peritoneal tissue concentrations of Nab-PTX, in parallel with higher plasma concentrations. In conclusion, EP enhances spatial homogeneity and tissue uptake after intraperitoneal nebulization of anticancer NPs.


Assuntos
Nanopartículas , Peritônio , Aerossóis , Animais , Sistemas de Liberação de Medicamentos , Humanos , Ratos , Eletricidade Estática
3.
J Anat ; 236(5): 862-882, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31814126

RESUMO

In classic anatomy teaching, the brachial plexus generally features as an enigmatic rote-learned structure, leaving the student with a feeling of complexity. The notion of complexity may increase in dissections, where plexuses significantly differing from the standard plexus model are readily found. This raises questions: what determines the existence and prevalence of variants and to what degree should they be considered anomalous? A model linking brachial plexus morphology and its variability to causative morphological parameters which would also standardize plexus description and teaching would be beneficial. The present study aims to provide such a model by analyzing the context of plexus development and applying this model in the analysis of plexus variability in anatomical specimens. Based on a thorough literature review, a generic developmental model was formulated and different factors of variability defined. In 56 plexuses, the proposed generic principles of plexus variability were found consistent with the variations encountered. Summarized, the modeled generic principles are as follows. Brachial plexus axon bundles grow out into an environment of chemical tracer paths in which constraints and obstacles are present: the geometry of the arm bud, cartilaginous bone precursors and vessels. The overall constancy of these factors generates a gross plexus outline, while the variability in these factors gives rise to typical plexus variations. The usefulness of the model derives from the fact that the variability of the main morphologically determining factors is not random but is the expression of the possibilities of the embryological substrate. Within the model, the major plexus morphological determinant is the segmental position of the subclavian artery, which is determined by the segment level of the intersegmental artery from which it develops. Normally, the subclavian artery develops from intersegmental artery i7. However, the subclavian artery can develop from inferior or superior segmental levels, from intersegmental artery i8 or i6, and possibly also from i9 or i5. Each of these arterial variants creates a typical, morphologically distinct, predictable plexus configuration. Superimposed on these basic plexus configurations, the underlying embryological substrate may develop further variability by integrating remnants of other intersegmental arteries into the arterial network. The resulting plexus configurations are further modified by local factors, e.g. the splitting of outgrowing axon bundles around vessels. A large split in the lateral cord around a large vein or veins crossing from lateral to medial, tangentially cranially over the subclavian artery was found in 54% of the 56 investigated BP and therefore might be added to plexus teaching. The distinct plexus morphologies associated with the subclavian artery segmental levels were further found associated with, among others, typical variations in the pectoral nerves and their ansas; these associations were also modeled. The presented models could allow brachial plexus rote learning to be replaced by a more insightful narrative of formative principles suitable for teaching. Clinically, improved understanding of the relationship between plexus variability and the local anatomical environment should be relevant to brachial plexus surgery and reconstruction.


Assuntos
Plexo Braquial/anatomia & histologia , Modelos Anatômicos , Artéria Subclávia/anatomia & histologia , Dissecação , Humanos
4.
World J Surg ; 43(11): 2902-2908, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31375870

RESUMO

OBJECTIVES: The purpose of this study was to evaluate the feedback of participants upon laparoscopic liver surgery (LLS) course on Thiel-embalmed human bodies. METHODS: From 2010 to 2017, ten LLS masterclasses have been organized by the Department of Hepatobiliary Surgery at Ghent University Hospital. A 23-question anonymous survey was electronically sent to 119 participants between November 2017 and January 2018, exploring their characteristics and asking for evaluation of the course. The obstacles for implementing LLS in their centers have been assessed. RESULTS: Sixty-four surgeons (53.8%) responded to the survey; 42 (65.6%) were employed at a university hospital; and 39 (60.9%) were in the first decade of their practice as a consultant surgeon. Forty-three (67.2%) surgeons reported an increased percentage of LLS cases afterward. Training on Thiel cadavers was considered superior (49.2%) to other training options including proctoring in the operating room (34.9%), virtual reality (6.3%), video training (4.8%) and practicing on pigs (4.8%). Obstacles identified contained inadequate training, patient's referral pattern, financial issues, lack of dedicated surgical team and time constrains. CONCLUSIONS: This survey revealed that a structured short-time program incorporating interactive discussion, live operations and hands-on training on human bodies under proctorship may enhance efficient training in laparoscopic liver surgery. In a step forward for upcoming courses, the importance of team building has to be addressed.


Assuntos
Atitude do Pessoal de Saúde , Laparoscopia/educação , Fígado/cirurgia , Animais , Cadáver , Embalsamamento , Docentes de Medicina , Humanos , Avaliação de Programas e Projetos de Saúde , Treinamento por Simulação , Inquéritos e Questionários , Suínos
5.
Acta Chir Belg ; 118(3): 141-151, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29653497

RESUMO

BACKGROUND: The role of reperfused human cadavers in surgical training has not been established. METHODS: Reports describing reperfused human cadaver models in terms of simulated surgeries, the use of tools to assess technical competency and skills transfer to patients, cadaver status and reperfusion techniques were included. RESULTS: Thirty-five reports were included. Most participants practised vascular (n = 27), flap (n = 6) and trauma (n = 4) procedures. Training progression was evaluated objectively in only two studies. In two publications, flap techniques were practised on cadavers and repeated successfully in patients. Eighteen studies employed whole bodies. Fresh and embalmed cadavers were both used in 17 publications. Most embalmed cadavers were formalin-fixed (n = 10), resulting in stiffness. Few trainings were offered on soft Thiel-embalmed cadavers (n = 5). Only arteries were reperfused in 20 studies, while in 13 publications, the arteries and veins were filled. Arteries and/or veins were mostly pressurized (n = 21) and arterial flow was generated in 14 studies. CONCLUSIONS: Various reperfused human cadaver models exist, enabling practise of mainly vascular procedures. Preservation method determines the level of simulation fidelity. Thorough evaluation of these models as surgical training tools and transfer effectiveness is still lacking.


Assuntos
Embalsamamento , Procedimentos Cirúrgicos Operatórios/educação , Cadáver , Avaliação Educacional , Feminino , Cirurgia Geral/educação , Humanos , Masculino , Sensibilidade e Especificidade , Procedimentos Cirúrgicos Vasculares/educação
6.
Immunol Rev ; 280(1): 207-219, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-29027225

RESUMO

Necroptosis is one the best-characterized forms of regulated necrosis. Necroptosis is mediated by the kinase activities of receptor interacting protein kinase-1 and receptor interacting protein kinase-3, which eventually lead to the activation of mixed lineage kinase domain-like. Necroptosis is characterized by rapid permeabilization of the plasma membrane, which is associated with the release of the cell content and subsequent exposure of damage-associated molecular patterns (DAMPs) and cytokines/chemokines. This release underlies the immunogenic nature of necroptotic cancer cells and their ability to induce efficient anti-tumor immunity. Triggering necroptosis has become especially important in experimental cancer treatments as an alternative to triggering apoptosis because one of the hallmarks of cancer is the blockade or evasion of apoptosis. In this review, we discuss recent advances in necroptosis research and the functional consequences of necroptotic cancer cell death, with focus on its immunogenicity and its role in the activation of anti-tumor immunity. Next, we discuss the molecular mechanisms of phosphatidylserine exposure during necroptosis and its role in the recognition of necroptotic cells. We also highlight the complex role of the necroptotic pathway in tumor promotion and suppression and in metastasis. Future studies will show whether necroptosis is truly a better strategy to overcome apoptosis resistance and provide the insights needed for development of novel treatment strategies for cancer.


Assuntos
Apoptose , Vacinas Anticâncer/imunologia , Morte Celular , Dano ao DNA/imunologia , DNA/imunologia , Imunoterapia/métodos , Necrose , Animais , Citocinas/metabolismo , Humanos , Fosfatidilserinas/metabolismo , Evasão Tumoral
7.
J Clin Pathol ; 70(10): 838-846, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28360190

RESUMO

AIM: Nowadays, extracellular vesicles are of great interest in prostate cancer (PCa) research. Asparagine (N)-linked glycosylation could play a significant role in the pathological mechanism of these vesicles. We investigated if prostatic protein N-glycosylation profiles were related to urinary vesicle-associated prostate-specific antigen (PSA) extractability and if this parameter showed diagnostic potential for PCa. METHODS: Urinary extracellular vesicles were visualised using transmission electron microscopy. Urinary extracellular vesicles extraction by means of n-butanol allowed determination of urinary vesicle-associated PSA extractability. Diagnostic value was assessed between benign prostate hyperplasia (BPH; n=122) and patients with PCa (n=85). Additionally, correlation with urine N-glycosylation was assessed. RESULTS: Urinary extracellular vesicles with a diameter of approximately 100 nm were more abundantly present in urine of patients with PCa versus patients with BPH resulting in a higher vesicle-associated PSA extraction ratio (p<0.001). Next, vesicle-associated PSA extraction ratio was correlated to biantennary core-fucosylation (p=0.003). Finally, vesicle-associated PSA extraction ratio proved beneficial in PCa diagnosis, next to serum PSA and the urinary glycosylation marker (p=0.021). CONCLUSIONS: The urinary vesicle-associated PSA extraction ratio is increased in PCa which is a direct result of the abundant presence of extracellular vesicles in urine of patients with PCa. The urinary vesicle-associated PSA extraction ratio was associated with changes in N-glycoforms and showed diagnostic potential. Further research is warranted to unravel the pathological link between N-glycosylation and extracellular vesicles in cancer, as well as to assess the prognostic value of this biomarker.


Assuntos
Biomarcadores Tumorais/urina , Vesículas Extracelulares/metabolismo , Antígeno Prostático Específico/urina , Neoplasias da Próstata/urina , Idoso , Área Sob a Curva , Glicosilação , Humanos , Masculino , Microscopia Eletrônica de Transmissão , Pessoa de Meia-Idade , Curva ROC
8.
Eur Surg Res ; 56(3-4): 97-108, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26788718

RESUMO

BACKGROUND: Vascular reperfusion of Thiel cadavers can aid surgical and anatomical instruction. This study investigated whether ideal embalming circumstances provide lifelike vascular flow, enabling surgical practice and enhancing anatomical reality. METHODS: Pressure-controlled pump-driven administration of blue embalming solution was assessed directly postmortem in a pig model (n = 4). Investigation of subsequent pump-driven vascular injection of red paraffinum perliquidum (PP) included assessment of flow parameters, intracorporeal distribution, anatomical alterations, and feasibility for surgical training. The microscopic distribution of PP was analyzed in pump-embalmed pig and gravity-embalmed human small intestines. RESULTS: Embalming lasted 50-105 min, and maximum arterial pressure was 65 mm Hg. During embalming, the following consecutive alterations were observed: arterial filling, organ coloration, venous perfusion, and further tissue coloration during the next weeks. Most organs were adequately preserved. PP generated low arterial pressures (<30 mm Hg) and drained through the venous cannula. Generally, realistic reperfusion and preservation of original anatomy were observed, but leakage in the pleural, abdominal, and retroperitoneal cavities occurred, and computed tomography showed edematous spleen and liver. Reduction of arterial flow rates after venous drainage is a prerequisite to prevent anatomical deformation, allowing simulation of various surgeries. In pump-embalmed pig small intestines, PP flowed from artery to vein through the capillaries without extravasation. In contrast, arterioles were blocked in gravity-embalmed human tissues. CONCLUSIONS: In a pig model, immediate postmortem pressure-controlled pump embalming generates ideal circumstances for (micro)vascular reperfusion with PP, permitting lifelike anatomy instruction and surgical training.


Assuntos
Embalsamamento , Cirurgia Geral/educação , Modelos Animais , Reperfusão , Animais , Humanos , Suínos
9.
Infect Immun ; 84(1): 293-306, 2016 01.
Artigo em Inglês | MEDLINE | ID: mdl-26527212

RESUMO

Helicobacter heilmannii naturally colonizes the stomachs of dogs and cats and has been associated with gastric disorders in humans. Nine feline Helicobacter strains, classified as H. heilmannii based on ureAB and 16S rRNA gene sequences, were divided into a highly virulent and a low-virulence group. The genomes of these strains were sequenced to investigate their phylogenetic relationships, to define their gene content and diversity, and to determine if the differences in pathogenicity were associated with the presence or absence of potential virulence genes. The capacities of these helicobacters to bind to the gastric mucosa were investigated as well. Our analyses revealed that the low-virulence strains do not belong to the species H. heilmannii but to a novel, closely related species for which we propose the name Helicobacter ailurogastricus. Several homologs of H. pylori virulence factors, such as IceA1, HrgA, and jhp0562-like glycosyltransferase, are present in H. heilmannii but absent in H. ailurogastricus. Both species contain a VacA-like autotransporter, for which the passenger domain is remarkably larger in H. ailurogastricus than in H. heilmannii. In addition, H. ailurogastricus shows clear differences in binding to the gastric mucosa compared to H. heilmannii. These findings highlight the low-virulence character of this novel Helicobacter species.


Assuntos
Mucosa Gástrica/microbiologia , Gastrite/microbiologia , Helicobacter heilmannii/genética , Helicobacter heilmannii/patogenicidade , Mucosa Intestinal/microbiologia , Animais , Aderência Bacteriana/genética , Proteínas de Bactérias/genética , Gatos , Linhagem Celular , Desoxirribonucleases de Sítio Específico do Tipo II/genética , Cães , Células Epiteliais/microbiologia , Mucosa Gástrica/citologia , Gerbillinae , Glicosiltransferases/genética , Infecções por Helicobacter/microbiologia , Helicobacter heilmannii/classificação , Humanos , Mucosa Intestinal/citologia , Dados de Sequência Molecular , Filogenia , Estrutura Terciária de Proteína , RNA Ribossômico 16S/genética , Virulência/genética , Zoonoses/microbiologia
10.
Reprod Fertil Dev ; 28(12): 1926-1944, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26085435

RESUMO

The oviduct undergoes dramatic functional and morphological changes throughout the oestrous cycle of the mare. To unravel the effects of steroids on the morphology, functionality and gene expression of the equine oviduct, an in vitro oviduct explant culture system was stimulated with physiological concentrations of progesterone and 17ß-oestradiol. Four conditions were compared: unsupplemented preovulatory explants, preovulatory explants that were stimulated with postovulatory hormone concentrations, unsupplemented postovulatory explants and postovulatory explants that were stimulated with preovulatory hormone concentrations. The modulating effects of both steroids on oviduct explants were investigated and the following parameters examined: (1) ciliary activity, (2) glucose consumption and lactate production pattern, (3) ultrastructure, (4) mRNA expression of embryotrophic genes, (5) steroidogenic capacities of oviductal explants and (6) progesterone receptor expression. The present paper shows that the equine oviduct is an organ with potential steroidogenic capacities, which is highly responsive to local changes in progesterone and 17ß-oestradiol concentrations at the level of morphology, functionality and gene expression of the oviduct. These data provide a basis to study the importance of endocrine and paracrine signalling during early embryonic development in the horse.


Assuntos
Estradiol/farmacologia , Tubas Uterinas/fisiologia , Glucose/metabolismo , Progesterona/farmacologia , Receptores de Progesterona/metabolismo , Animais , Feminino , Cavalos , Técnicas de Cultura de Órgãos
11.
Indian J Surg ; 77(Suppl 2): 712-5, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26730095

RESUMO

The purpose of this experimental study was to establish a short-term post-mortem circulation in a pig model using liquid paraffin. This study also investigated the quality of vascular perfusion in the peripheral tissues. This is the first step in the development of a new revascularized human surgical training model. This first experience was performed on the hind leg of a pig. Initial cannulation of the external iliac artery and vein was followed by connection of the arterial inflow to a heart-lung machine and using the venous outflow to flush post-mortem clots and blood. Subsequently, after connecting the venous outflow to the heart-lung machine, circulation was initiated. Circulation was established during 27 min, during which the flow was constantly 130 mL/min. A steady increase in inlet pressure was observed during the experiment, which finally reached a minimum value of 124 mmHg. Perfusion was interrupted early due to an uncontrollable fluid leak. Afterwards, the distal hind leg was incised showing an equal distribution of paraffin. A short-term revascularization was successfully re-established under excellent conditions. Although the results are promising, further experiments are necessary to eventually perform a wide range of surgical procedures on revascularized human cadavers.

12.
Strahlenther Onkol ; 190(7): 628-32, 634-5, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24715246

RESUMO

PURPOSE: The goal of this work was to validate the Radiation Therapy Oncology Group (RTOG)-endorsed guidelines for brachial plexus (BP) contouring by determining the intra- and interobserver agreement. Accuracy of the delineation process was determined using anatomically validated imaging datasets as a gold standard. MATERIALS AND METHODS: Five observers delineated the right BP on three cadaver computed tomography (CT) datasets. To assess intraobserver variation, every observer repeated each delineation three times with a time interval of 2 weeks. The BP contours were divided into four regions for detailed analysis. Inter- and intraobserver variation was verified using the Computerized Environment for Radiation Research (CERR) software. Accuracy was measured using anatomically validated fused CT-magnetic resonance imaging (MRI) datasets by measuring the BP inclusion of the delineations. RESULTS: The overall kappa (κ) values were rather low (mean interobserver overall κ: 0.29, mean intraobserver overall κ: 0.45), indicating poor inter- and intraobserver reliability. In general, the κ coefficient decreased gradually from the medial to lateral BP regions. The total agreement volume (TAV) was much smaller than the union volume (UV) for all delineations, resulting in a low Jaccard index (JI; interobserver agreement 0-0.124; intraobserver agreement 0.004-0.636). The overall accuracy was poor, with an average total BP inclusion of 38%. Inclusions were insufficient for the most lateral regions (region 3: 21.5%; region 4: 12.6%). CONCLUSION: The inter- and intraobserver reliability of the RTOG-endorsed BP contouring guidelines was poor. BP inclusion worsened from the medial to lateral regions. Accuracy assessment of the contours showed an average BP inclusion of 38%. For the first time, this was assessed using the original anatomically validated BP volume. The RTOG-endorsed BP guidelines have insufficient accuracy and reliability, especially for the lateral head-and-neck regions.


Assuntos
Plexo Braquial/diagnóstico por imagem , Oncologia/normas , Guias de Prática Clínica como Assunto , Proteção Radiológica/normas , Radioterapia Guiada por Imagem/normas , Tomografia Computadorizada por Raios X/normas , Idoso , Cadáver , Feminino , Humanos , Masculino , Doses de Radiação , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
13.
Surg Radiol Anat ; 36(4): 375-81, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-23995518

RESUMO

INTRODUCTION: Recently, arthroscopy of the sternoclavicular joint (SCJ) has been described in clinical setting. The aim of this study is to examine the accessibility and safety of the SCJ by arthroscopy in a cadaveric model. MATERIALS AND METHODS: An inferolateral and superomedial portal to the SCJ was created in 20 cadaveric specimens. After debridement, the specimens were dissected with a needle positioned in the portal tracts. The distance between the needles and bony landmarks, tendons and ligaments were measured. The integrity of the posterior capsule was evaluated macroscopically. In eight specimens, after anterior dissection, the needles were replaced by K-wires that perforated the posterior capsule to evaluate the distance to the neurovascular structures behind the SCJ. RESULTS: Both portals were found to be safe while allowing good access to the joint. The superomedial portal went through the tendon of the sternocleidomastoideus muscle and the inferolateral portal through the pectoralis major muscle. The portals entered the capsule medial and lateral to the anterior sternoclavicular ligament. The posterior capsule was never perforated during debridement. The perforating K-wires, however, usually perforated either a major vein or artery, but were at a safe distance from the vagal nerve. CONCLUSIONS: In this cadaver study, arthroscopy of the sternoclavicular joint could be used as a minimally invasive procedure allowing debridement of the joint without damaging the posterior capsule of the joint. If the capsule is inadvertently be breached, a major risk of neurovascular damage exists. We advise to have a backup of a cardiothoracic surgeon when performing this procedure.


Assuntos
Artroscopia/métodos , Articulação Esternoclavicular/anatomia & histologia , Articulação Esternoclavicular/cirurgia , Cadáver , Dissecação , Humanos
14.
Reprod Fertil Dev ; 26(7): 954-66, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23902648

RESUMO

Equine embryos remain for 6 days in the oviduct and thus there is a need for an in vitro model to study embryo-oviductal interactions in the horse, since this subtle way of communication is very difficult to analyse in vivo. Until now, no equine oviduct explant culture model has been characterised both morphologically and functionally. Therefore, we established a culture system for equine oviduct explants that maintained epithelial morphology during 6 days of culture, as revealed by light microscopy and transmission electron microscopy. We demonstrated the presence of highly differentiated, tall columnar, pseudostratified epithelium with basal nuclei, numerous nucleoli, secretory granules and apical cilia, which is very similar to the in vivo situation. Both epithelium and stromal cells originating from the lamina propria are represented in the explants. Moreover, at least 98% of the cells remained membrane intact and fewer than 2% of the cells were apoptotic after 6 days of culture. Although dark-cell degeneration, which is a hypoxia-related type of cell death, was observed in the centre of the explants, quantitative real-time PCR failed to detect upregulation of the hypoxia-related marker genes HIF1A, VEGFA, uPA, GLUT1 and PAI1. Since the explants remained morphologically and functionally intact and since the system is easy to set up, it appears to be an excellent tool for proteome, transcriptome and miRNome analysis in order to unravel embryo-maternal interactions in the horse.


Assuntos
Técnicas de Cultura de Células/veterinária , Embrião de Mamíferos/fisiologia , Tubas Uterinas/fisiologia , Cavalos/embriologia , Cavalos/fisiologia , Modelos Biológicos , Animais , Apoptose , Técnicas de Cultura de Células/métodos , Hipóxia Celular/genética , Células Epiteliais/fisiologia , Células Epiteliais/ultraestrutura , Tubas Uterinas/citologia , Feminino , Expressão Gênica , Glucose/metabolismo , Marcação In Situ das Extremidades Cortadas , Ácido Láctico/metabolismo , Microscopia Eletrônica de Transmissão , Mucosa/citologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa/veterinária , Células Estromais/fisiologia , Células Estromais/ultraestrutura , Fatores de Tempo , Transcriptoma
15.
Int J Radiat Oncol Biol Phys ; 87(4): 802-8, 2013 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-24138919

RESUMO

PURPOSE: To develop contouring guidelines for the brachial plexus (BP) using anatomically validated cadaver datasets. Magnetic resonance imaging (MRI) and computed tomography (CT) were used to obtain detailed visualizations of the BP region, with the goal of achieving maximal inclusion of the actual BP in a small contoured volume while also accommodating for anatomic variations. METHODS AND MATERIALS: CT and MRI were obtained for 8 cadavers positioned for intensity modulated radiation therapy. 3-dimensional reconstructions of soft tissue (from MRI) and bone (from CT) were combined to create 8 separate enhanced CT project files. Dissection of the corresponding cadavers anatomically validated the reconstructions created. Seven enhanced CT project files were then automatically fitted, separately in different regions, to obtain a single dataset of superimposed BP regions that incorporated anatomic variations. From this dataset, improved BP contouring guidelines were developed. These guidelines were then applied to the 7 original CT project files and also to 1 additional file, left out from the superimposing procedure. The percentage of BP inclusion was compared with the published guidelines. RESULTS: The anatomic validation procedure showed a high level of conformity for the BP regions examined between the 3-dimensional reconstructions generated and the dissected counterparts. Accurate and detailed BP contouring guidelines were developed, which provided corresponding guidance for each level in a clinical dataset. An average margin of 4.7 mm around the anatomically validated BP contour is sufficient to accommodate for anatomic variations. Using the new guidelines, 100% inclusion of the BP was achieved, compared with a mean inclusion of 37.75% when published guidelines were applied. CONCLUSION: Improved guidelines for BP delineation were developed using combined MRI and CT imaging with validation by anatomic dissection.


Assuntos
Plexo Braquial/anatomia & histologia , Plexo Braquial/diagnóstico por imagem , Imageamento Tridimensional/métodos , Guias de Prática Clínica como Assunto/normas , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada/métodos , Idoso , Cadáver , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Ilustração Médica , Posicionamento do Paciente/métodos , Tomografia Computadorizada por Raios X/métodos
16.
PLoS One ; 8(10): e77966, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24147103

RESUMO

Helicobacter (H.) suis colonizes the stomach of the majority of pigs as well as a minority of humans worldwide. Infection causes chronic inflammation in the stomach of the host, however without an effective clearance of the bacteria. Currently, no information is available about possible mechanisms H. suis utilizes to interfere with the host immune response. This study describes the effect on various lymphocytes of the γ-glutamyl transpeptidase (GGT) from H. suis. Compared to whole cell lysate from wild-type H. suis, lysate from a H. suis ggt mutant strain showed a decrease of the capacity to inhibit Jurkat T cell proliferation. Incubation of Jurkat T cells with recombinantly expressed H. suis GGT resulted in an impaired proliferation, and cell death was shown to be involved. A similar but more pronounced inhibitory effect was also seen on primary murine CD4(+) T cells, CD8(+) T cells, and CD19(+) B cells. Supplementation with known GGT substrates was able to modulate the observed effects. Glutamine restored normal proliferation of the cells, whereas supplementation with reduced glutathione strengthened the H. suis GGT-mediated inhibition of proliferation. H. suis GGT treatment abolished secretion of IL-4 and IL-17 by CD4(+) T cells, without affecting secretion of IFN-γ. Finally, H. suis outer membrane vesicles (OMV) were identified as a possible delivery route of H. suis GGT to lymphocytes residing in the deeper mucosal layers. Thus far, this study is the first to report that the effects on lymphocytes of this enzyme, not only important for H. suis metabolism but also for that of other Helicobacter species, depend on the degradation of two specific substrates: glutamine and reduced glutatione. This will provide new insights into the pathogenic mechanisms of H. suis infection in particular and infection with gastric helicobacters in general.


Assuntos
Membrana Celular/metabolismo , Glutamina/farmacologia , Glutationa/farmacologia , Helicobacter heilmannii/enzimologia , Linfócitos/metabolismo , gama-Glutamiltransferase/metabolismo , Animais , Antígenos CD19/metabolismo , Linfócitos B/metabolismo , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Células Cultivadas , Interleucina-17/metabolismo , Interleucina-4/metabolismo , Camundongos , Transporte Proteico/efeitos dos fármacos
17.
PLoS One ; 8(5): e64644, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23734212

RESUMO

Clostridium perfringens ß-toxin (CPB) is a ß-barrel pore-forming toxin and an essential virulence factor of C. perfringens type C strains, which cause fatal hemorrhagic enteritis in animals and humans. We have previously shown that CPB is bound to endothelial cells within the intestine of affected pigs and humans, and that CPB is highly toxic to primary porcine endothelial cells (pEC) in vitro. The objective of the present study was to investigate the type of cell death induced by CPB in these cells, and to study potential host cell mechanisms involved in this process. CPB rapidly induced lactate dehydrogenase (LDH) release, propidium iodide uptake, ATP depletion, potassium efflux, a marked rise in intracellular calcium [Ca(2+)]i, release of high-mobility group protein B1 (HMGB1), and caused ultrastructural changes characteristic of necrotic cell death. Despite a certain level of caspase-3 activation, no appreciable DNA fragmentation was detected. CPB-induced LDH release and propidium iodide uptake were inhibited by necrostatin-1 and the two dissimilar calpain inhibitors PD150606 and calpeptin. Likewise, inhibition of potassium efflux, chelation of intracellular calcium and treatment of pEC with cyclosporin A also significantly inhibited CPB-induced LDH release. Our results demonstrate that rCPB primarily induces necrotic cell death in pEC, and that necrotic cell death is not merely a passive event caused by toxin-induced membrane disruption, but is propagated by host cell-dependent biochemical pathways activated by the rise in intracellular calcium and inhibitable by necrostatin-1, consistent with the emerging concept of programmed necrosis ("necroptosis").


Assuntos
Toxinas Bacterianas/farmacologia , Calpaína/metabolismo , Células Endoteliais/efeitos dos fármacos , Imidazóis/farmacologia , Indóis/farmacologia , Acrilatos/farmacologia , Animais , Western Blotting , Cálcio/metabolismo , Calpaína/antagonistas & inibidores , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Membrana Celular/ultraestrutura , Células Cultivadas , Inibidores de Cisteína Proteinase/farmacologia , Fragmentação do DNA/efeitos dos fármacos , Dipeptídeos/farmacologia , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Citometria de Fluxo , Proteína HMGB1/metabolismo , Espaço Intracelular/efeitos dos fármacos , Espaço Intracelular/metabolismo , Transporte de Íons/efeitos dos fármacos , L-Lactato Desidrogenase , Microscopia Eletrônica de Transmissão , Necrose , Potássio/metabolismo , Suínos
18.
Knee Surg Sports Traumatol Arthrosc ; 21(5): 1005-10, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23269474

RESUMO

PURPOSE: The bony insertion sites of the PCL have been studied and described extensively using 2D technology such as macroscopic images, plain radiograph, computerized tomography (CT) and MRI. The purpose of this study is to visualize both the tibial and the femoral bony insertion sites but also the soft tissue anatomy of the native PCL using novel 3D CT imaging. In addition, new concepts of best-fit cylinder and central axis are introduced and evaluated. METHODS: Nine unpaired knees of embalmed cadavers were used in this study. Following the dissection process, the PCL was injected with a contrast medium for computed tomography (CT) imaging. The obtained CT images were segmented and rendered in 3D allowing morphological and morphometric analysis of PCL. Femoral and tibial footprint surface area, best-fit PCL-cylinder intersection area, best-fit PCL-cylinder/footprint coverage ratio, best-fit PCL-cylinder central axis projections at the tibial and femoral footprint were used to describe the anatomy of the PCL. RESULTS: Mean footprint surface area of the tibial and femoral footprint were 189.1 and 293.3 mm², respectively. The mean diameter of the best-fit cylinder was 10.5 mm. The mean coverage of the best-fit cylinder on the tibial and femoral footprint was 76.5 and 46.5, respectively. The best-fit cylinder central axis was located in the anterolateral AL bundle footprint on the femur and more centrally in the PCL footprint on the tibia. CONCLUSION: This study is the first to describe the detailed anatomy of the human PCL with respect to its course and footprints using a 3D approach. It confirms the large difference between the tibial and the femoral footprint area with the former being significantly smaller. In addition, a large inter-patient variability is observed. The best-fit cylinder and central axis concept offer additional insights into the optimal tunnel placement at the tibia and femoral footprint in order to cover the largest portion of the native PCL soft tissue.


Assuntos
Fêmur/diagnóstico por imagem , Articulação do Joelho/diagnóstico por imagem , Ligamento Cruzado Posterior/diagnóstico por imagem , Tíbia/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Idoso , Idoso de 80 Anos ou mais , Cadáver , Feminino , Fêmur/anatomia & histologia , Humanos , Imageamento Tridimensional , Articulação do Joelho/anatomia & histologia , Masculino , Ligamento Cruzado Posterior/anatomia & histologia , Tíbia/anatomia & histologia
19.
Anticancer Drugs ; 23(9): 883-96, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22797176

RESUMO

Sesquiterpene lactones (SLs) constitute a large and diverse group of biologically active plant compounds that possess anti-inflammatory and antitumor activity. The subclass germacranolides is one of the major groups of SLs. It includes parthenolide, a highly cytotoxic SL that is being tested in clinical trials as an anti-cancer agent. In this review, we focus on SL antitumor activity related to cell-cycle arrest, differentiation, apoptosis induction through the intrinsic pathway, and sensitization of the extrinsic pathway. We also address the regression of tumors in response to cotreatment with conventional chemotherapeutics. We review the nuclear factor-κB-targeted anti-inflammatory activity in vitro and in vivo and relate it to the SL structural features involved in the molecular mechanisms. It is obvious that SLs are emerging as promising anticancer agents, but more investigations are required to fully understand the molecular mechanisms of known SLs in different cell death modalities and how these mechanisms contribute toward the potent antitumor and anti-inflammatory activities of SLs.


Assuntos
Anti-Inflamatórios não Esteroides/uso terapêutico , Antineoplásicos Fitogênicos/uso terapêutico , Neoplasias/tratamento farmacológico , Sesquiterpenos/uso terapêutico , Animais , Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/isolamento & purificação , Antineoplásicos Fitogênicos/administração & dosagem , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Humanos , Estrutura Molecular , NF-kappa B/antagonistas & inibidores , Neoplasias/imunologia , Neoplasias/patologia , Plantas Medicinais , Relação Quantitativa Estrutura-Atividade , Sesquiterpenos/administração & dosagem , Sesquiterpenos/química , Sesquiterpenos/isolamento & purificação , Ensaios Antitumorais Modelo de Xenoenxerto
20.
Vet Res ; 43: 32, 2012 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-22515231

RESUMO

Although aspergillosis is one of the most common diseases in captive birds, the pathogenesis of avian aspergillosis is poorly known. We studied the role of avian respiratory macrophages as a first line of defense against avian aspergillosis. The phagocytic and killing capacities of avian respiratory macrophages were evaluated using pigeon respiratory macrophages that were inoculated with Aspergillus fumigatus conidia. On average, 25% of macrophage-associated conidia were phagocytosed after one hour. Sixteen percents of these cell-associated conidia were killed after 4 h and conidial germination was inhibited in more than 95% of the conidia. A. fumigatus conidia were shown to be cytotoxic to the macrophages. Intracellularly germinating conidia were located free in the cytoplasm of necrotic cells, as shown using transmission electron microscopy. These results suggest that avian respiratory macrophages may prevent early establishment of infection, unless the number of A. fumigatus conidia exceeds the macrophage killing capacity, leading to intracellular germination and colonization of the respiratory tract.


Assuntos
Aspergilose/veterinária , Aspergillus fumigatus/crescimento & desenvolvimento , Doenças das Aves/imunologia , Columbidae , Macrófagos Alveolares/imunologia , Animais , Aspergilose/imunologia , Aspergilose/microbiologia , Aspergillus fumigatus/imunologia , Doenças das Aves/microbiologia , Citotoxicidade Imunológica , Macrófagos Alveolares/microbiologia , Microscopia Eletrônica de Transmissão/veterinária , Microscopia de Fluorescência/veterinária , Sistema Respiratório , Esporos Fúngicos/crescimento & desenvolvimento , Esporos Fúngicos/imunologia
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