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BACKGROUND/AIMS: Charcot-Marie-Tooth Disease type 1A (CMT1A), the most common inherited peripheral neuropathy, is characterized by progressive sensory loss and weakness, which results in impaired mobility. Increased understanding of the genetics and pathophysiology of CMT1A has led to development of potential therapeutic agents, necessitating clinical trial readiness. Wearable sensors may provide useful outcome measures for future trials. METHODS: Individuals with CMT1A and unaffected controls were recruited for this 12-month study. Participants wore sensors for in-clinic assessments and at-home, from which activity, gait, and balance metrics were derived. Mann-Whitney U tests were used to analyze group differences for activity, gait, and balance parameters. Test-retest reliability of gait and balance parameters and correlations of these parameters with clinical outcome assessments (COAs) were examined. RESULTS: Thirty individuals, 15 CMT1A, and 15 controls, participated. Gait and balance metrics demonstrated moderate to excellent reliability. CMT1A participants had longer step durations (p < .001), shorter step lengths (p = .03), slower gait speeds (p < .001), and greater postural sway (p < .001) than healthy controls. Moderate correlations were found between CMT-Functional Outcome Measure and step length (r = -0.59; p = .02), and gait speed (r = 0.64; p = .01); 11 out of 15 CMT1A participants demonstrated significant increases in stride duration between the first and last quarter of the 6-min walk test, suggesting fatigue. INTERPRETATION: In this initial study, gait and balance metrics derived from wearable sensors were reliable and associated with COAs in individuals with CMT1A. Larger longitudinal studies are needed to confirm our findings and evaluate sensitivity and utility of these disease-specific algorithms for clinical trial use.
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Doença de Charcot-Marie-Tooth , Dispositivos Eletrônicos Vestíveis , Humanos , Marcha , Estudos Longitudinais , Reprodutibilidade dos TestesRESUMO
BACKGROUND: The application of artificial intelligence is a relatively new option to enable improved patient treatment in modern medicine and is therefore currently the focus of many research projects. In the clinical practice the application of artificial intelligence so far seems to be confined to the analysis of medical imaging. OBJECTIVE: In which form is the use of artificial intelligence possible in routine daily work in thoracic surgery and is already being practiced? MATERIAL AND METHODS: A search of the currently available literature was performed. RESULTS: Under current conditions artificial intelligence can best be used as part of diagnostics and treatment planning; however, in order to enable a comprehensive use standardization and evaluation of the centralized data collection are necessary. CONCLUSION: At the present time promising study results are available but the implementation into the surgical routine has so far been very difficult.
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Inteligência Artificial , Cirurgia Torácica , Humanos , Aprendizado de MáquinaRESUMO
A recently proposed variational principle with a discontinuous Lagrangian for viscous flow is reinterpreted against the background of stochastic variational descriptions of dissipative systems, underpinning its physical basis from a different viewpoint. It is shown that additional non-classical contributions to the friction force occurring in the momentum balance vanish by time averaging. Accordingly, the discontinuous Lagrangian can alternatively be understood from the standpoint of an analogous deterministic model for irreversible processes of stochastic character. A comparison is made with established stochastic variational descriptions and an alternative deterministic approach based on a first integral of Navier-Stokes equations is undertaken. The applicability of the discontinuous Lagrangian approach for different Reynolds number regimes is discussed considering the Kolmogorov time scale. A generalization for compressible flow is elaborated and its use demonstrated for damped sound waves.
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A young man presented with haemoptysis, eight years after foreign body aspiration. The initial evaluation took place in the emergency department of a general hospital. However, neither chest x-ray nor bronchoscopy were performed. Bronchoscopy performed in our hospital revealed a foreign body in right lower lobe bronchus. Extraction failed because it was embedded in granulation tissue. The chronic atelectasis of right lower lobe and recurrent bronchopulmonary infections during the last years were the indication for lobectomy.
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Brônquios/diagnóstico por imagem , Broncoscopia/métodos , Corpos Estranhos/diagnóstico por imagem , Hemoptise/etiologia , Pneumonectomia , Atelectasia Pulmonar/diagnóstico por imagem , Atelectasia Pulmonar/cirurgia , Humanos , Masculino , Atelectasia Pulmonar/etiologia , Traqueia , Resultado do TratamentoRESUMO
OBJECTIVES: Evaluation of a standardised management for the treatment of patients with parapneumonic empyema. METHODS: A retrospective 10-year single-centre analysis of all patients with parapneumonic empyema undergoing a standardised thoracoscopic treatment approach. We describe referral and age patterns, microbiological results, overall and stage-dependent success rates, conversion rates, 30-day and in-hospital mortality. RESULTS: From May 2003 to April 2013, 248 patients with parapneumonic empyemas were treated in our centre. Most patients were referred at weekends, and younger patients had advanced stages. The cure rate in stage I was 97.6â% and reached 80.3â% in stage II and 63.1â% in stage III. 6 patients (2.4â%) (all stage III) needed conversion to an open procedure. A revision was required in 19.7â% of cases in stage II and 27.7â% in stage III. 30-day mortality was 4.8â%, in-hospital mortality was 8.1â%. CONCLUSION: A standardised approach, including VATS, is associated with a high cure, low revision and moderate conversion rates. In view of a still considerable mortality, a higher index of suspicion and detection of advanced stages, especially in younger patients, is required to improve outcomes.
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Empiema/cirurgia , Cirurgia Torácica Vídeoassistida , Toracostomia , Empiema/mortalidade , Alemanha/epidemiologia , Mortalidade Hospitalar , Humanos , Tempo de Internação , Masculino , Derrame Pleural/cirurgia , Estudos Retrospectivos , Resultado do TratamentoRESUMO
E-cadherin and ß-catenin are key proteins that are essential in the formation of the epithelial cell layer in the colon but their regulatory pathways that are disrupted in cancer metastasis are not completely understood. Mutated in colorectal cancer (MCC) is a tumour suppressor gene that is silenced by promoter methylation in colorectal cancer and particularly in patients with increased lymph node metastasis. Here, we show that MCC methylation is found in 45% of colon and 24% of rectal cancers and is associated with proximal colon, poorly differentiated, circumferential and mucinous tumours as well as increasing T stage and larger tumour size. Knockdown of MCC in HCT116 colon cancer cells caused a reduction in E-cadherin protein level, which is a hallmark of epithelial-mesenchymal transition in cancer, and consequently diminished the E-cadherin/ß-catenin complex. MCC knockdown disrupted cell-cell adhesive strength and integrity in the dispase and transepithelial electrical resistance assays, enhanced hepatocyte growth factor-induced cell scatter and increased tumour cell invasiveness in an organotypic assay. The Src/Abl inhibitor dasatinib, a candidate anti-invasive drug, abrogated the invasive properties induced by MCC deficiency. Mechanistically, we establish that MCC interacts with the E-cadherin/ß-catenin complex. These data provide a significant advance in the current understanding of cell-cell adhesion in colon cancer cells.
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Caderinas/metabolismo , Adesão Celular/genética , Neoplasias Colorretais/patologia , Proteínas Supressoras de Tumor/deficiência , beta Catenina/metabolismo , Antígenos CD , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Adesão Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Estudos de Coortes , Colo/citologia , Colo/patologia , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Neoplasias Colorretais/mortalidade , Metilação de DNA/genética , Dasatinibe/farmacologia , Dasatinibe/uso terapêutico , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Células HCT116 , Humanos , Metástase Linfática , Invasividade Neoplásica/genética , Estadiamento de Neoplasias , Prognóstico , Regiões Promotoras Genéticas/genética , Ligação Proteica/genética , Proteínas Supressoras de Tumor/genéticaRESUMO
The observation and manipulation of electron dynamics in matter call for attosecond light pulses, routinely available from high-order harmonic generation driven by few-femtosecond lasers. However, the energy limitation of these lasers supports only weak sources and correspondingly linear attosecond studies. Here we report on an optical parametric synthesizer designed for nonlinear attosecond optics and relativistic laser-plasma physics. This synthesizer uniquely combines ultra-relativistic focused intensities of about 1020 W/cm2 with a pulse duration of sub-two carrier-wave cycles. The coherent combination of two sequentially amplified and complementary spectral ranges yields sub-5-fs pulses with multi-TW peak power. The application of this source allows the generation of a broad spectral continuum at 100-eV photon energy in gases as well as high-order harmonics in relativistic plasmas. Unprecedented spatio-temporal confinement of light now permits the investigation of electric-field-driven electron phenomena in the relativistic regime and ultimately the rise of next-generation intense isolated attosecond sources.
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Pancreatic cancer has a devastating prognosis, with an overall 5-year survival rate of ~8%, restricted treatment options and characteristic molecular heterogeneity. SerpinB2 expression, particularly in the stromal compartment, is associated with reduced metastasis and prolonged survival in pancreatic ductal adenocarcinoma (PDAC) and our genomic analysis revealed that SERPINB2 is frequently deleted in PDAC. We show that SerpinB2 is required by stromal cells for normal collagen remodelling in vitro, regulating fibroblast interaction and engagement with collagen in the contracting matrix. In a pancreatic cancer allograft model, co-injection of PDAC cancer cells and SerpinB2-/- mouse embryonic fibroblasts (MEFs) resulted in increased tumour growth, aberrant remodelling of the extracellular matrix (ECM) and increased local invasion from the primary tumour. These tumours also displayed elevated proteolytic activity of the primary biochemical target of SerpinB2-urokinase plasminogen activator (uPA). In a large cohort of patients with resected PDAC, we show that increasing uPA mRNA expression was significantly associated with poorer survival following pancreatectomy. This study establishes a novel role for SerpinB2 in the stromal compartment in PDAC invasion through regulation of stromal remodelling and highlights the SerpinB2/uPA axis for further investigation as a potential therapeutic target in pancreatic cancer.
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Carcinoma Ductal Pancreático/patologia , Neoplasias Pancreáticas/patologia , Inibidor 2 de Ativador de Plasminogênio/metabolismo , Microambiente Tumoral , Animais , Carcinoma Ductal Pancreático/metabolismo , Fibroblastos/metabolismo , Fibroblastos/patologia , Perfilação da Expressão Gênica , Humanos , Camundongos , Microscopia Eletrônica de Varredura , Neoplasias Pancreáticas/metabolismo , TranscriptomaRESUMO
Epigenetic changes, such as DNA methylation, play an essential role in the acquisition of full developmental competence by mammalian oocytes during the late follicular growth phase. Here we used the bovine model to investigate the DNA methylation profiles of seven candidate genes (imprinted: bH19, bSNRPN; non-imprinted: bZAR1, bDNMT3A, bOCT4, bDNMT3 Lo and bDNMT3 Ls) and the mRNA expression of nine candidate genes (imprinted: bSNRPN, bPEG3, bIGF2R; non-imprinted: bPRDX1, bDNMT1B, bDNMT3A, bZAR1, bHSF1 and bNLRP9) in oocytes from antral follicles of three different size classes (≤2mm, 3-5mm, ≥6mm) to unravel the epigenetic contribution to this process. We observed an increased number of aberrantly methylated alleles in bH19, bSNRPN and bDNMT3 Lo of oocytes from small antral follicles (≤2mm), correlating with lower developmental competence. Furthermore, we detected an increased frequency of CpG sites with an unclear methylation status for DNMT3 Ls, specifically in oocytes from follicles ≥6mm, predominantly at three CpG positions (CpG2, CpG7 and CpG8), of which CpG7 is a potential regulatory site. No major differences in mRNA expression were observed, indicating that the transcriptional machinery may not yet be active during the follicular growth phase. Our results support the notion that a follicle diameter of ~2mm is a critical stage for establishing DNA methylation profiles and indicate a link between DNA methylation and the acquisition of oocyte developmental competence.
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Metilação de DNA , Oócitos/metabolismo , Folículo Ovariano/metabolismo , RNA Mensageiro/metabolismo , Animais , Bovinos , Epigênese Genética , Feminino , Perfilação da Expressão Gênica , Oogênese/genética , RNA Mensageiro/genéticaRESUMO
Bovine embryos produced in vivo and in vitro differ with respect to molecular profiles, including epigenetic marks and gene expression profiles. This study investigated the CpG methylation status in bovine testis satellite I (BTS) and Bos taurus alpha satellite I (BTαS) DNA sequences, and concomitantly the relative abundance of transcripts, critically involved in DNA methylation (DNMT1 and DNMT3A), growth and development (IGF2R) and pluripotency (POU5F1) in Bos indicus embryos produced in vitro or in vivo. Results revealed that methylation of BTS were higher (P < 0.05) in embryos produced in vitro compared with their in vivo produced counterparts, while the methylation status of BTαS was similar in both groups. There were no significant differences in transcript abundance for DNMT3A, IGF2R and POU5F1 between blastocysts produced in vivo and in vitro. However, a significantly lower amount of DNMT1 transcripts was found in the in vitro cultured embryos (P < 0.05) compared with their in vivo derived counterparts. In conclusion, this study reported only minor changes in the expression of developmentally important genes and satellite DNA methylation related to the in vitro embryo production system.
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Blastocisto/metabolismo , DNA (Citosina-5-)-Metiltransferases/genética , Metilação de DNA , DNA Satélite/genética , Regulação da Expressão Gênica no Desenvolvimento , Fator 3 de Transcrição de Octâmero/genética , Oócitos/metabolismo , Receptor IGF Tipo 2/genética , Animais , Blastocisto/citologia , Bovinos , Células Cultivadas , Técnicas de Cultura Embrionária , Feminino , Fertilização in vitro , Técnicas In Vitro , Oócitos/citologiaRESUMO
Background: Publication bias is an over-representation of statistically significant results in the published literature and may exaggerate summary effect estimates in oncology systematic reviews. Omitting non-significant results in systematic reviews may therefore affect clinical decision-making. We investigate ways that systematic reviewers attempted to limit publication bias during the search process as well as the statistical methods used to evaluate it. For a subset of reviews not reporting publication bias evaluations, we carried out our own assessments for publication bias to determine its likelihood among these reviews. Design: We examined systematic reviews from the top five highest impact factor oncology journals published between 2007 and 2015. Systematic reviews were screened for eligibility and qualifying reviews (n = 182) were coded for relevant publication bias study characteristics by two authors. A re-analysis of reviews not initially evaluating for publication bias was carried out using Egger's regression, trim-and-fill, and selection models. Results: Of the 182 systematic reviews, roughly half carried out a hand search to locate additional studies. Conference abstracts were the most commonly reported form of gray literature, followed by clinical trials registries. Fifty-one reviews reported publication bias evaluations. The most common method was the funnel plot (80%, 41/51) followed by Egger's regression (59%, 30/51) and Begg's test (43%, 22/51). Our publication bias evaluations on non-reporting reviews suggest that the degree of publication bias depends on the method employed. Conclusion: Our study shows publication bias assessments are not frequently used in oncology systematic reviews. Furthermore, evidence of publication bias was found in a subset of non-reporting reviews. Systematic reviewers in oncology are encouraged to conduct such analyses when appropriate and to employ more robust methods for both mitigating and evaluating publication bias.
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Tomada de Decisão Clínica , Oncologia , Viés de Publicação , Humanos , Fator de Impacto de Revistas , Relatório de PesquisaRESUMO
Allogeneic stem cell transplantation (alloSCT) is used for treating patients with T-prolymphocytic leukemia (T-PLL). However, direct evidence of GvL activity in T-PLL is lacking. We correlated minimal residual disease (MRD) kinetics with immune interventions and T-cell receptor (TCR) repertoire diversity alterations in patients after alloSCT for T-PLL. Longitudinal quantitative MRD monitoring was performed by clone-specific real-time PCR of TCR rearrangements (n=7), and TCR repertoire diversity assessment by next-generation sequencing (NGS; n=3) Although post-transplant immunomodulation (immunosuppression tapering or donor lymphocyte infusions) resulted in significant reduction (>1 log) of MRD levels in 7 of 10 occasions, durable MRD clearance was observed in only two patients. In all three patients analyzed by TCR-NGS, MRD responses were reproducibly associated with a shift from a clonal, T-PLL-driven profile to a polyclonal signature. Novel clonotypes that could explain a clonal GvL effect did not emerge. In conclusion, TCR-based MRD quantification appears to be a suitable tool for monitoring and guiding treatment interventions in T-PLL. The MRD responses to immune modulation observed here provide first molecular evidence for GvL activity in T-PLL which, however, may be often only transient and reliant on a poly-/oligoclonal rather than a monoclonal T-cell response.
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Efeito Enxerto vs Leucemia , Imunomodulação , Leucemia Prolinfocítica de Células T/terapia , Neoplasia Residual/diagnóstico , Receptores de Antígenos de Linfócitos T/análise , Transplante de Células-Tronco/métodos , Adulto , Idoso , Células Clonais/imunologia , Rearranjo Gênico do Linfócito T/genética , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Cinética , Leucemia Prolinfocítica de Células T/diagnóstico , Pessoa de Meia-Idade , Neoplasia Residual/genética , Reação em Cadeia da Polimerase em Tempo Real , Receptores de Antígenos de Linfócitos T/genética , Transplante HomólogoRESUMO
Three genetically different clones of Toxoplasma gondii, also different in mouse virulence, were studied by experimental infection in chickens. For the experiments, four chicken lines were used, which differed in phylogenetic origin and performance level: two white egg layer lines, one with high laying performance (WLA), one with low (R11) and two brown layer lines, also displaying high (BLA) and low (L68) egg number. Chickens were intraperitoneally infected with three different T. gondii isolates representing type IIxIII recombinant clones, i.e. showing both, type II- and type III-specific alleles. These clones (K119/2 2C10, B136/1 B6H6, K119/2 A7) had exhibited virulence differences in a mouse model. In chickens, a significantly higher mortality was observed in white layer lines, but not in brown layer lines, suggesting that differences in the phylogenetic background may influence the susceptibility of chickens for toxoplasmosis. In addition, antibody (IgY) levels varied in surviving chickens at 31 days post infection. While low to intermediate antibody levels were observed in white layers, intermediate to high levels were measured in brown layers. Infection with a T. gondii clone showing low chicken virulence resulted in higher antibody levels in all chicken lines compared to infection with T. gondii clones of intermediate or high chicken virulence. This was in agreement with the parasite load as determined by real-time PCR. Overall, results show that progeny resulting from natural sexual recombination of T. gondii clonal lineages, may differ in their virulence for mice and chickens.
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Galinhas/parasitologia , Doenças das Aves Domésticas/mortalidade , Toxoplasma/patogenicidade , Toxoplasmose Animal/mortalidade , Animais , Anticorpos Antiprotozoários/sangue , Encéfalo/parasitologia , Galinhas/classificação , Galinhas/genética , DNA de Protozoário/análise , Ensaio de Imunoadsorção Enzimática , Genótipo , Imunoglobulina G/sangue , Imunoglobulinas/sangue , Pulmão/parasitologia , Camundongos , Camundongos Endogâmicos BALB C , Polimorfismo de Fragmento de Restrição , Doenças das Aves Domésticas/parasitologia , Reação em Cadeia da Polimerase em Tempo Real , Toxoplasma/classificação , Toxoplasma/genética , Toxoplasma/imunologia , Toxoplasmose Animal/parasitologia , VirulênciaRESUMO
Management of urban hydrologic processes using green infrastructure (GI) has largely focused on stormwater management. Thus, design and implementation of GI usually rely on physical site characteristics and local rainfall patterns, and do not typically account for human or social dimensions. This traditional approach leads to highly centralized stormwater management in a disconnected urban landscape, and can deemphasize additional benefits that GI offers, such as increased property value, greenspace aesthetics, heat island amelioration, carbon sequestration, and habitat for biodiversity. We propose a Framework for Adaptive Socio-Hydrology (FrASH) in which GI planning and implementation moves from a purely hydrology-driven perspective to an integrated socio-hydrological approach. This allows for an iterative, multifaceted decision-making process that would enable a network of stakeholders to collaboratively set a dynamic, context-guided project plan for the installation of GI, rather than a 'one-size-fits-all' installation. We explain how different sectors (e.g., governance, non-governmental organizations, academia, and industry) can create a connected network of organizations that work towards a common goal. Through a graphical Chambered Nautilus model, FrASH is experimentally applied to contrasting GI case studies and shows that this multi-stakeholder, connected, de-centralized network with a co-evolving decision-making project plan results in enhanced multi-functionality, potentially allowing for the management of resilience in urban systems at multiple scales.
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BACKGROUND AND AIMS: Several studies demonstrated that larger neck circumference (NC) in children and adolescents may help to identify obesity and cardio-metabolic abnormalities. We aimed to evaluate the correlation between NC and metabolic syndrome (MetS) risk factors and to determine the utility of this anthropometric index to identify MetS in European children. METHODS AND RESULTS: The present cross-sectional analysis includes 15,673 children (3-10 years) participating in the IDEFICS study. A continuous MetS (cMetS) score was calculated summing age and sex standardized z-scores of specific MetS risk factors. Receiver Operating Characteristic analysis, stratified by one-year age groups, was used to determine the ability of NC to identify children with unfavorable metabolic profile, corresponding to cMetS score ≥ 90th percentile. The areas under the curve values for NC associated with cMetS score values ≥ 90th percentile were significantly greater in girls than in boys (p < 0.001), except for 5 < 6 years group. For boys, optimal NC cut-off values ranged from 26.2 cm for the lowest age group (3 < 4 years), up to 30.9 cm for the highest age group (9 < 10 years). In girls, corresponding values varied from 24.9 cm to 29.6 cm. CONCLUSION: The study demonstrated the efficacy of NC in identifying European children with an unfavorable metabolic profile.
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Antropometria/métodos , Síndrome Metabólica/diagnóstico , Pescoço/patologia , Fatores Etários , Área Sob a Curva , Criança , Pré-Escolar , Estudos Transversais , Europa (Continente)/epidemiologia , Feminino , Humanos , Masculino , Síndrome Metabólica/epidemiologia , Síndrome Metabólica/patologia , Valor Preditivo dos Testes , Curva ROC , Fatores SexuaisRESUMO
A previous study on domestic cats in Germany and neighbouring countries suggested seasonality in shedding Toxoplasma gondii oocysts. The aim of the present study was to elucidate whether this seasonality in shedding could be explained by climatic effects and whether differences between years in the proportions of cats shedding oocysts could also be explained by climatic factors. To this end, a long-term study over a period of 55 months on domestic cats for T. gondii and Hammondia hammondi oocysts was performed and the results compared with climatic data. Using species-specific PCR, T. gondii oocysts were identified in 0.14% (84/61,224) and H. hammondi in 0.10% (61/61,224) of the samples. Toxoplasma gondii oocysts were predominantly observed from summer to autumn, while H. hammondi oocysts were mainly found during autumn and winter. In statistical analyses using climatic data, even differences in parasitological findings between years could be partially modelled using monthly temperature, North Atlantic Oscillation indices and precipitation. Of the three climatic variables analysed, precipitation as an explanatory variable had the lowest impact in the statistical models while those taking only temperature and North Atlantic Oscillation indices into account were sufficiently predictive. Interestingly, time lags between the climatic event and the parasitological findings had to be implemented in all models. For T. gondii, North Atlantic Oscillation indices with a time lag of 7 months and temperature with a time lag of 2 months had the best predictive value. In contrast, temperature (with a time lag of 6 months) and the interaction of precipitation (with a time lag of 5 months) and North Atlantic Oscillation indices (with a time lag of 11 months) were optimal for predicting the seasonality of H. hammondi. These results suggest prominent differences in the life cycles of the two closely related parasites. Previous findings showed that H. hammondi lack avian hosts, in contrast to T. gondii, and the coincidence in the periods of high abundance of birds and high proportions of cats shedding T. gondii suggest that birds may play an important role in the epidemiology of this infection. The result that North Atlantic Oscillation index is an important variable in modelling variations in the proportion of cats shedding T. gondii and H. hammondi over the year is an indication that global warming may also influence the infection risk of animals and humans with T. gondii and H. hammondi. The findings have important implications for planning epidemiological studies and for estimating the risk of human infection.
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Coccidiose/veterinária , Fezes/parasitologia , Sarcocystidae/isolamento & purificação , Toxoplasma/isolamento & purificação , Toxoplasmose Animal/epidemiologia , Animais , Gatos , Clima , Coccidiose/epidemiologia , Coccidiose/parasitologia , Modelos Lineares , Modelos Biológicos , Estações do Ano , Toxoplasmose Animal/parasitologiaRESUMO
Acute vascular rejection (AVR), in particular microvascular thrombosis, is an important barrier to successful pig-to-primate xenotransplantation. Here, we report the generation of pigs with decreased tissue factor (TF) levels induced by small interfering (si)RNA-mediated gene silencing. Porcine fibroblasts were transfected with TF-targeting small hairpin (sh)RNA and used for somatic cell nuclear transfer. Offspring were analyzed for siRNA, TF mRNA and TF protein level. Functionality of TF downregulation was investigated by a whole blood clotting test and a flow chamber assay. TF siRNA was expressed in all twelve liveborn piglets. TF mRNA expression was reduced by 94.1 ± 4.7% in TF knockdown (TFkd) fibroblasts compared to wild-type (WT). TF protein expression in PAEC stimulated with 50 ng/mL TNF-α was significantly lower in TFkd pigs (mean fluorescence intensity TFkd: 7136 ± 136 vs. WT: 13 038 ± 1672). TF downregulation significantly increased clotting time (TFkd: 73.3 ± 8.8 min, WT: 45.8 ± 7.7 min, p < 0.0001) and significantly decreased thrombus formation compared to WT (mean thrombus coverage per viewing field in %; WT: 23.5 ± 13.0, TFkd: 2.6 ± 3.7, p < 0.0001). Our data show that a functional knockdown of TF is compatible with normal development and survival of pigs. TF knockdown could be a valuable component in the generation of multi-transgenic pigs for xenotransplantation.
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Interferência de RNA , RNA Interferente Pequeno/metabolismo , Tromboplastina/metabolismo , Trombose/patologia , Transplante Heterólogo , Animais , Animais Geneticamente Modificados , Coagulação Sanguínea , Regulação para Baixo , Fibroblastos/metabolismo , Técnicas Genéticas , Rejeição de Enxerto , Humanos , Masculino , Sus scrofa , Testículo/citologiaRESUMO
Current knowledge on bovine besnoitiosis, caused by the emerging apicomplexan pathogen Besnoitia besnoiti, is still fragmentary. So far, studies dealing with ultrastructural pathology focused mainly on the easily accessible chronic stage, whereas ultrastructural investigations of tachyzoites were confined to in vitro studies. In the study presented here, the ultrastructural pathology of naturally B. besnoiti-infected cattle in the acute and chronic disease stages and experimentally B. besnoiti-infected mice was monitored. Further, the ultrastructure of tachyzoites and bradyzoites was investigated. Skin samples of two adult Limousin cows and one adult Limousin bull naturally infected with B. besnoiti and liver and skin samples of gamma-interferon knockout mice infected with B. besnoiti were examined in semithin sections stained with toluidine blue and safranin and in ultrathin sections contrasted with uranyl acetate and lead citrate. Samples of vessel walls of the bull and nasal mucosa of one cow were examined by scanning electron microscopy. Few tachyzoites-like endozoites were detected for the first time in bovine skin, and large numbers of tachyzoites were detected in murine skin and liver. Within tissue cysts in bovine skin, numerous bradyzoites were observed displaying signs of degeneration. Tachyzoites had apicomplexan endozoite ultrastructure. B. besnoiti tachyzoites and bradyzoites differed in shape and the number of amylopectin granules. Transmission and scanning electron microscopy confirmed the presence of two different cyst wall layers, and the present results on cyst wall ultrastructure were in accordance with those previously obtained by histological sections.