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BACKGROUND: The aim of this study was to evaluate the interobserver reliability of measurements of the Acromiohumeral Distance (AHD) first described by Golding et al., the Critical Shoulder Angle (CSA), the Acromion Index with Glenoid Humeral (GH) and Glenoid Acromial (GA) distances, following the measuring method by Nyffeler et al., the Lateral Acromion Angle (LAA), as well as the morphology of the acromion according to Bigliani and the humeral head position according to Maloney in X-rays and MRI. Furthermore, the study assessed the correlation of measurement results in X-ray with those in MRI for AHD, CSA, GA, GH, AI, and LAA. METHODS: A total of 187 patients who underwent shoulder joint X-ray and MRI examinations from 09/2016 to 05/2023 were included in the study. Patients with poor imaging quality, arthrosis or radical prior surgeries, like shoulder prosthetic surgery, status post humerus fractures, that have undergone surgery and therefore changed the anatomical features were excluded, what lead to a total study population of 78. X-ray measurements were performed by two observers in the true anteroposterior view, so that the humeral head and the glenoid are shown without overlap, providing a clear view into the joint space. MRI measurements were performed in oblique coronal MRI slices, using the most accurately depicted glenoid surface as a landmark. RESULTS: Interobserver measurement results showed a significance with p < 0.001 for the assessment of acromion type according to Bigliani, humeral head offset assessment according to Maloney, and AHD. No significance was found for interobserver reliability in measuring LAA. Additionally, there was a high correlation of measurement results in X-ray with measurements in MRI for, CSA, GH/GA, and consequently AI, a good correlation for AHD but no correlation could be shown for LAA. CONCLUSIONS: These findings provide valuable insights into the robustness of radiological parameters for evaluating shoulder pathology, offering promising prospects for clinical applications and further research. Nevertheless, the specific methodological considerations and patient characteristics should be taken into account when interpreting the results to ensure their accurate application in clinical practice.
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A20 is a ubiquitin-modifying protein that negatively regulates NF-κB signaling. Mutations in A20/TNFAIP3 are associated with a variety of autoimmune diseases, including multiple sclerosis (MS). We found that deletion of A20 in central nervous system (CNS) endothelial cells (ECs) enhances experimental autoimmune encephalomyelitis (EAE), a mouse model of MS. A20ΔCNS-EC mice showed increased numbers of CNS-infiltrating immune cells during neuroinflammation and in the steady state. While the integrity of the blood-brain barrier (BBB) was not impaired, we observed a strong activation of CNS-ECs in these mice, with dramatically increased levels of the adhesion molecules ICAM-1 and VCAM-1. We discovered ICOSL to be expressed by A20-deficient CNS-ECs, which we found to function as adhesion molecules. Silencing of ICOSL in CNS microvascular ECs partly reversed the phenotype of A20ΔCNS-EC mice without reaching statistical significance and delayed the onset of EAE symptoms in WT mice. In addition, blocking of ICOSL on primary mouse brain microvascular ECs impaired the adhesion of T cells in vitro. Taken together, we propose that CNS EC-ICOSL contributes to the firm adhesion of T cells to the BBB, promoting their entry into the CNS and eventually driving neuroinflammation.
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Encefalomielite Autoimune Experimental , Doenças Neuroinflamatórias , Proteína 3 Induzida por Fator de Necrose Tumoral alfa , Animais , Camundongos , Barreira Hematoencefálica/metabolismo , Sistema Nervoso Central/metabolismo , Células Endoteliais/metabolismo , Camundongos Endogâmicos C57BL , Esclerose Múltipla/metabolismo , Doenças Neuroinflamatórias/metabolismo , Linfócitos T/metabolismo , Ligante Coestimulador de Linfócitos T Induzíveis/metabolismo , Proteína 3 Induzida por Fator de Necrose Tumoral alfa/metabolismoRESUMO
Coronavirus disease 2019 (COVID-19) can damage cerebral small vessels and cause neurological symptoms. Here we describe structural changes in cerebral small vessels of patients with COVID-19 and elucidate potential mechanisms underlying the vascular pathology. In brains of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-infected individuals and animal models, we found an increased number of empty basement membrane tubes, so-called string vessels representing remnants of lost capillaries. We obtained evidence that brain endothelial cells are infected and that the main protease of SARS-CoV-2 (Mpro) cleaves NEMO, the essential modulator of nuclear factor-κB. By ablating NEMO, Mpro induces the death of human brain endothelial cells and the occurrence of string vessels in mice. Deletion of receptor-interacting protein kinase (RIPK) 3, a mediator of regulated cell death, blocks the vessel rarefaction and disruption of the blood-brain barrier due to NEMO ablation. Importantly, a pharmacological inhibitor of RIPK signaling prevented the Mpro-induced microvascular pathology. Our data suggest RIPK as a potential therapeutic target to treat the neuropathology of COVID-19.
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Barreira Hematoencefálica/metabolismo , Encéfalo/metabolismo , Proteases 3C de Coronavírus/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Microvasos/metabolismo , SARS-CoV-2/metabolismo , Animais , Barreira Hematoencefálica/patologia , Encéfalo/patologia , Chlorocebus aethiops , Proteases 3C de Coronavírus/genética , Cricetinae , Feminino , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Masculino , Mesocricetus , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Microvasos/patologia , SARS-CoV-2/genética , Células VeroRESUMO
Cerebral small-vessel diseases (SVDs) often follow a progressive course. Little is known about the function of angiogenesis, which potentially induces regression of SVDs. Here, we investigated angiogenesis in a mouse model of incontinentia pigmenti (IP), a genetic disease comprising features of SVD. IP is caused by inactivating mutations of Nemo, the essential component of NF-κB signaling. When deleting Nemo in the majority of brain endothelial cells (NemobeKO mice), the transcriptional profile of vessels indicated cell proliferation. Brain endothelial cells expressed Ki67 and showed signs of DNA synthesis. In addition to cell proliferation, we observed sprouting and intussusceptive angiogenesis in NemobeKO mice. Angiogenesis occurred in all segments of the vasculature and in proximity to vessel rarefaction and tissue hypoxia. Apparently, NEMO was required for productive angiogenesis because endothelial cells that had escaped Nemo inactivation showed a higher proliferation rate than Nemo-deficient cells. Therefore, newborn endothelial cells were particularly vulnerable to ongoing recombination. When we interfered with productive angiogenesis by inducing ongoing ablation of Nemo, mice did not recover from IP manifestations but rather showed severe functional deficits. In summary, the data demonstrate that angiogenesis is present in this model of SVD and suggest that it may counterbalance the loss of vessels.
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Indutores da Angiogênese/metabolismo , Isquemia Encefálica/fisiopatologia , Células Endoteliais/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , NF-kappa B/metabolismo , Neovascularização Fisiológica/fisiologia , Animais , Modelos Animais de Doenças , Humanos , Camundongos , Camundongos KnockoutRESUMO
INTRODUCTION: . Meningitis and endocarditis are common pathologies of Streptococcussuis infections in pigs and humans. S. suis serotype 9 strains contribute substantially to health problems in European pig production, and immune prophylaxis against this serotype is very difficult. CASE PRESENTATION: . We report the clinical course and histopathological picture of a 10-week-old growing pig following experimental intravenous infection with S. suis serotype 9. The piglet showed rapid onset of severe clinical signs of meningitis 11 days post-intravenous challenge following prime-booster vaccination. Histopathological findings revealed a diffuse fibrinosuppurative leptomeningitis. Additionally, a polyphasic endocarditis valvularis thromboticans with numerous bacterial colonies was diagnosed. Bacteriological culture of the brain and the mitral valve confirmed association with the challenge strain. However, virulent serotype 2 and 9 strains were killed in the blood of this piglet ex vivo prior experimental infection. CONCLUSION: . Endocarditis induced by S. suis infection might develop and persist despite the presence of high specific bactericidal activity in the blood. Severe leptomeningitis is a putative sequela of such an endocarditis.
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OBJECTIVE: We aimed to determine whether multienergy spectral photon-counting CT could distinguish between clinically relevant calcium crystals at clinical x-ray energy ranges. Energy thresholds of 15, 22, 29, and 36 keV and tube voltages of 50, 80, and 110 kVp were selected. Images were analyzed to assess differences in linear attenuation coefficients between various concentrations of calcium hydroxyapatite (54.3, 211.7, 808.5, and 1169.3 mg/cm3) and calcium oxalate (2000 mg/cm3). CONCLUSION: The two lower concentrations of hydroxyapatite were distinguishable from oxalate at all energy thresholds and tube voltages, whereas discrimination at higher concentrations depended primarily on the energy thresholds used. Multienergy spectral photon-counting CT shows promise for distinguishing these calcium crystals.
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Oxalato de Cálcio , Durapatita , Tomografia Computadorizada por Raios X , Imagens de Fantasmas , FótonsRESUMO
Brain endothelial cells are the major building block of the blood-brain barrier. To study the role of brain endothelial cells in vitro, the isolation of primary cells is of critical value. Here, we describe a protocol in which vessel fragments are isolated from adult mice. After density centrifugation and mild digestion of the fragments, outgrowing endothelial cells are selected by puromycin treatment and grown to confluence within one week.
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Doenças de Pequenos Vasos Cerebrais/metabolismo , Doenças de Pequenos Vasos Cerebrais/patologia , Doenças de Pequenos Vasos Cerebrais/fisiopatologia , Animais , Humanos , Incontinência Pigmentar/metabolismo , Incontinência Pigmentar/patologia , Incontinência Pigmentar/fisiopatologia , Fator de Crescimento Transformador beta/metabolismoRESUMO
Streptococcus suis is an important meningitis-causing pathogen in pigs and humans. Neutrophil extracellular traps (NETs) have been identified as host defense mechanism against different pathogens. Here, NETs were detected in the cerebrospinal fluid (CSF) of S. suis-infected piglets despite the presence of active nucleases. To study NET-formation and NET-degradation after transmigration of S. suis and neutrophils through the choroid plexus epithelial cell barrier, a previously described model of the human blood-CSF barrier was used. NETs and respective entrapment of streptococci were recorded in the "CSF compartment" despite the presence of active nucleases. Comparative analysis of S. suis wildtype and different S. suis nuclease mutants did not reveal significant differences in NET-formation or bacterial survival. Interestingly, transcript expression of the human cathelicidin LL-37, a NET-stabilizing factor, increased after transmigration of neutrophils through the choroid plexus epithelial cell barrier. In good accordance, the porcine cathelicidin PR-39 was significantly increased in CSF of piglets with meningitis. Furthermore, we confirmed that PR-39 is associated with NETs in infected CSF and inhibits neutrophil DNA degradation by bacterial nucleases. In conclusion, neutrophils form NETs after breaching the infected choroid plexus epithelium, and those NETs may be protected by antimicrobial peptides against bacterial nucleases.
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Líquido Cefalorraquidiano/imunologia , Líquido Cefalorraquidiano/microbiologia , Armadilhas Extracelulares/imunologia , Neutrófilos/imunologia , Infecções Estreptocócicas/veterinária , Streptococcus suis/imunologia , Doenças dos Suínos/patologia , Animais , Animais Recém-Nascidos , Barreira Hematoencefálica , Catelicidinas/análise , Técnicas de Cultura de Células , Líquido Cefalorraquidiano/química , Líquido Cefalorraquidiano/citologia , Desoxirribonucleases/deficiência , Desoxirribonucleases/metabolismo , Viabilidade Microbiana , Infecções Estreptocócicas/imunologia , Infecções Estreptocócicas/patologia , Suínos , Doenças dos Suínos/imunologiaRESUMO
Photorespiration is essential for the detoxification of glycolate and recycling of carbon to the Calvin Benson Bassham cycle. Enzymes participating in the pathway have been identified, and investigations now focus on the regulation of photorespiration by transporters and metabolites. However, regulation of photorespiration on the gene level has not been intensively studied. Here, we show that maximum transcript abundance of Glu:glyoxylate aminotransferase 1 (GGT1) is regulated by intron-mediated enhancement (IME) of the 5' leader intron rather than by regulatory elements in the 5' upstream region. The intron is rich in CT-stretches and contains the motif TGTGATTTG that is highly similar to the IME-related motif TTNGATYTG. The GGT1 intron also confers leaf-specific expression of foreign promoters. Quantitative PCR analysis and GUS activity measurements revealed that IME of the GGT1 5'UTR intron is controlled on the transcriptional level. IME by the GGT1 5'UTR intron was at least 2-fold. Chromatin immunoprecipitation experiments showed that the abundance of RNA polymerase II binding to the intron-less construct is reduced.
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Regiões 5' não Traduzidas/genética , Regulação da Expressão Gênica de Plantas , Íntrons/genética , Regiões Promotoras Genéticas/genética , RNA Polimerase II/metabolismo , Transaminases/genética , Arabidopsis/genética , Arabidopsis/metabolismo , Sequência de Bases , Sítios de Ligação/genética , Motivos de Nucleotídeos/genética , Folhas de Planta/genética , Folhas de Planta/metabolismo , Plantas Geneticamente Modificadas , Ligação Proteica , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Homologia de Sequência do Ácido Nucleico , Transcrição GênicaRESUMO
OBJECTIVE: The aim of the present study was to verify the diagnostic validity of low-field magnetic-resonance-imaging (MRI) findings in septic diseases of the foot region following penetrating sole injuries caused by nails. MATERIALS AND METHODS: MRI examinations were performed in 10 horses with injuries in the foot region. The diagnostic findings were validated by conventional methods (clinical, surgical, radiological, sonographic, and computed tomographic findings and/or post-mortem histological examination). RESULTS: Navicular bone involvement was revealed most accurately, with a high degree of predictability, and was best detected by fat-suppressed T2 or short-TI inversion recovery (STIR) sequences. MRI examinations of defects in the deep digital flexor tendon showed a high level of sensitivity, but these findings were less specific than changes to the navicular bone. They could be best reproduced in transverse T2-weighted fast spin echo sequences (T2w FSE). The penetration tract was recognisable in all cases and in all planes, and the T2w FSE proved to be very suitable for diagnosis. Septic bursitis was revealed least accurately by MRI. Bursal disease was best recognised in the sagittal plane. CONCLUSION AND CLINICAL RELEVANCE: MRI is a reliable method for confirming the diagnosis of diseases in the foot region after injuries caused by foreign bodies, particularly nails. A transverse T2w FSE is best suited for demonstrating a penetration tract and tendon damage. Visualisation of the penetration tract and secondary reactions of the navicular bone are crucial for diagnosing bursitis. Fat-suppressed sequences can clearly show bone involvement when the penetration tract has not reached the bone. The cases described illustrate that MRI is an appropriate method for evaluating puncture wounds in the foot region. Only MRI allows for intravital assessment of various structures within the hoof capsule. This information is essential for deciding upon targeted therapy while avoiding unnecessary therapies.
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Casco e Garras/diagnóstico por imagem , Casco e Garras/lesões , Doenças dos Cavalos/diagnóstico por imagem , Cavalos/lesões , Imageamento por Ressonância Magnética , Animais , Imageamento por Ressonância Magnética/métodos , Imageamento por Ressonância Magnética/veterinária , Ossos do Tarso/diagnóstico por imagem , Ossos do Tarso/lesõesRESUMO
The aim of this study was to evaluate the uterine blood supply and endometrial vessel architecture, during the equine estrous cycle. Narrow Band Imaging (NBI) hysteroscopy was used for evaluating changes in the endometrial vasculature during the estrous cycle [six mares, d 0 (representing the day of ovulation), d 6 and 11 in four locations]. In addition, endometrial biopsy samples were used for immunodetection of markers for angiogenesis (Vascular Endothelial Growth Factor A, its receptor 2, as well as angiopoietin-2 and its receptor-tyrosine-kinase Tie2) during the estrous cycle (three mares, d 0, 5 and 10; one biopsy per mare). Detailed analysis of hysteroscopic images revealed an increase in the vascular density from estrus towards diestrus. In contrast, microscopic specimens prepared from biopsies revealed no evidence for changes in the endometrial vessel number during the estrous cycle. Studies on expression of angiogenesis markers indicated that cyclic changes in the endometrial vascular density observed by NBI-hysteroscopy were not due to formation of new vessels. It is concluded that vessels are involved in blood supply of a smaller area during diestrus, facilitating better distribution of nutrients during this phase.
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Endométrio/irrigação sanguínea , Endométrio/diagnóstico por imagem , Ciclo Estral/fisiologia , Cavalos , Histeroscopia , Imagem de Banda Estreita , Angiopoietina-2/metabolismo , Animais , Endométrio/metabolismo , Endométrio/patologia , Feminino , Cavalos/metabolismo , Histeroscopia/métodos , Histeroscopia/veterinária , Imagem de Banda Estreita/veterinária , Gravidez , Receptor TIE-2/metabolismo , Útero/irrigação sanguínea , Útero/diagnóstico por imagem , Fator A de Crescimento do Endotélio Vascular/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismoRESUMO
Ferlaviruses are important pathogens of snakes. However, factors influencing the pathogenicity of individual isolates as well as optimal protocols for virus detection in tissues of infected snakes have been insufficiently studied. The objectives of this study were to compare virus detection using previously described PCR and cell culture protocols following infection with three genetically distinct ferlaviruses in corn snakes (Pantherophis guttatus) as a model species. Groups of 12 corn snakes were each inoculated intratracheally with a genogroup A, B, or C ferlavirus. Tracheal washes and cloacal swabs were tested for virus shedding on days 16 and 28. Three animals were each euthanized on days 4, 16, 28, and 49. Beside immunohistochemistry of lung tissue, several organs (lung, intestine, pancreas, kidney, brain) were tested for the presence of ferlavirus. Distinct differences were noted in the pathogenicity of the three viruses, with a genotype B isolate causing the greatest pathology. PCR was more sensitive in comparison to cell culture, but results varied depending on the tissues. Ferlaviruses spread rapidly into the tissues, including the brain. Overall average detection rate was 72%, and was highest on day 16. There were differences between the groups, with the most virulent strain causing 100% positive samples at the end of the study. Some snakes were able to clear the infection. Shedding via cloaca was seen only on day 28. For ante-mortem sampling, a tracheal wash sample is recommended, for post mortem diagnosis, a pooled organ sample should be tested.
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Colubridae/virologia , Infecções por Paramyxoviridae/veterinária , Paramyxovirinae/genética , Animais , Células Cultivadas , Modelos Animais de Doenças , Infecções por Paramyxoviridae/genética , Infecções por Paramyxoviridae/fisiopatologia , Infecções por Paramyxoviridae/virologia , Paramyxovirinae/patogenicidade , Paramyxovirinae/fisiologia , Traqueia/virologia , Eliminação de Partículas ViraisRESUMO
Inactivating mutations of the NF-κB essential modulator (NEMO), a key component of NF-κB signaling, cause the genetic disease incontinentia pigmenti (IP). This leads to severe neurological symptoms, but the mechanisms underlying brain involvement were unclear. Here, we show that selectively deleting Nemo or the upstream kinase Tak1 in brain endothelial cells resulted in death of endothelial cells, a rarefaction of brain microvessels, cerebral hypoperfusion, a disrupted blood-brain barrier (BBB), and epileptic seizures. TAK1 and NEMO protected the BBB by activating the transcription factor NF-κB and stabilizing the tight junction protein occludin. They also prevented brain endothelial cell death in a NF-κB-independent manner by reducing oxidative damage. Our data identify crucial functions of inflammatory TAK1-NEMO signaling in protecting the brain endothelium and maintaining normal brain function, thus explaining the neurological symptoms associated with IP.
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Encéfalo/irrigação sanguínea , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , MAP Quinase Quinase Quinases/metabolismo , Animais , Barreira Hematoencefálica/metabolismo , Encéfalo/metabolismo , Circulação Cerebrovascular/genética , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Epilepsia/genética , Feminino , Quinase I-kappa B/metabolismo , Incontinência Pigmentar/metabolismo , Incontinência Pigmentar/patologia , Peptídeos e Proteínas de Sinalização Intracelular/genética , MAP Quinase Quinase Quinases/genética , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Ocludina/metabolismo , Fator 6 Associado a Receptor de TNF/metabolismo , Fator de Transcrição RelA/metabolismoRESUMO
Xenograft tumor models are widely studied in cancer research. Our aim was to establish and apply a model for aggressive CD20-positive B-cell non-Hodgkin lymphomas, enabling us to monitor tumor growth and shrinkage in a noninvasive manner. By stably transfecting a luciferase expression vector, we created two bioluminescent human non-Hodgkin lymphoma cell lines, Jeko1(luci) and OCI-Ly3(luci), that are CD20 positive, a prerequisite to studying rituximab, a chimeric anti-CD20 antibody. To investigate the therapy response in vivo, we established a disseminated xenograft tumor model injecting these cell lines in NOD/SCID mice. We observed a close correlation of bioluminescence intensity and tumor burden, allowing us to monitor therapy response in the living animal. Cyclophosphamide reduced tumor burden in mice injected with either cell line in a dose-dependent manner. Rituximab alone was effective in OCI-Ly3(luci)-injected mice and acted additively in combination with cyclophosphamide. In contrast, it improved the therapeutic outcome of Jeko1(luci)-injected mice only in combination with cyclophosphamide. We conclude that well-established bioluminescence imaging is a valuable tool in disseminated xenograft tumor models. Our model can be translated to other cell lines and used to examine new therapeutic agents and schedules.
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Progressão da Doença , Medições Luminescentes/métodos , Linfoma não Hodgkin/tratamento farmacológico , Linfoma não Hodgkin/patologia , Animais , Biomarcadores Tumorais/metabolismo , Contagem de Células , Linhagem Celular Tumoral , Ciclofosfamida/farmacologia , Ciclofosfamida/uso terapêutico , Modelos Animais de Doenças , Feminino , Luciferases/metabolismo , Masculino , Camundongos Endogâmicos NOD , Camundongos SCID , Especificidade de Órgãos/efeitos dos fármacos , Rituximab/farmacologia , Rituximab/uso terapêutico , Transfecção , Resultado do Tratamento , Carga TumoralRESUMO
Although it has been suggested that social deficits of autism spectrum disorders (ASDs) are related to reward circuitry dysfunction, very little is known about the neural reward mechanisms in ASD. In the current functional magnetic resonance imaging study, we investigated brain activations in response to both social and monetary reward in a group of children with ASD, relative to matched controls. Participants with ASD showed the expected hypoactivation in the mesocorticolimbic circuitry in response to both reward types. In particular, diminished activation in the nucleus accumbens was observed when money, but not when social reward, was at stake, whereas the amygdala and anterior cingulate cortex were hypoactivated within the ASD group in response to both rewards. These data indicate that the reward circuitry is compromised in ASD in social as well as in non-social, i.e. monetary conditions, which likely contributes to atypical motivated behaviour. Taken together, with incentives used in this study sample, there is evidence for a general reward dysfunction in ASD. However, more ecologically valid social reward paradigms are needed to fully understand, whether there is any domain specificity to the reward deficit that appears evident in ASD, which would be most consistent with the ASD social phenotype.
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Encéfalo/patologia , Transtornos Globais do Desenvolvimento Infantil/complicações , Transtornos Globais do Desenvolvimento Infantil/patologia , Deficiências da Aprendizagem/etiologia , Recompensa , Adolescente , Análise de Variância , Encéfalo/irrigação sanguínea , Estudos de Casos e Controles , Criança , Sinais (Psicologia) , Tomada de Decisões , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Motivação/fisiologia , Testes Neuropsicológicos , Oxigênio/sangue , Estimulação Luminosa , Tempo de Reação , Índice de Gravidade de Doença , Inquéritos e QuestionáriosRESUMO
By means of the official meat inspection of domestic pigs, exceptionally high proportions of livers affected by encapsulated nodules containing whitish to light yellow, viscous to pasty material ("microabscesses") were detected. The swine had been raised on four different farms, being located in distinct regions of Germany (Brandenburg, Thuringia, Upper Franconia). Macroscopical and histological examination of 77 samples of livers revealed granulomatous to necrotizing hepatitis with attendance of numerous eosinophils. In 61 % (n = 47) of the lesions, eosinophilic, band-like acellular structures resembling the laminated layer of Echinococcus sp. were visible. Moreover, representative samples (n = 11) showed a positive reaction of these structures with Periodic acid-Schiff. Altogether, the findings were consistent with alveolar echinococcosis. Echinococcus multilocularis DNA could be demonstrated in selected samples (n = 7) by polymerase chain reaction. Epidemiological considerations suggest contamination of the forage with fox tapeworm eggs to be the most likely source of infection on two of the farms, as some of the fodder had been stored in the open, being amenable to infected definitive hosts. On the two other farms, mainly straw litter has to be taken into account regarding the transmission route, since carnivores excreting eggs of E. multilocularis could have gained access to the straw storage. The presented cases show that adequate mechanisms of meat inspection may provide important data for the purposes of surveillance and risk assessment of human alveolar echinococcosis.
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Equinococose Hepática/veterinária , Echinococcus multilocularis/isolamento & purificação , Doenças dos Suínos/diagnóstico , Doenças dos Suínos/epidemiologia , Criação de Animais Domésticos , Animais , DNA de Helmintos/genética , Equinococose , Equinococose Hepática/diagnóstico , Equinococose Hepática/epidemiologia , Equinococose Hepática/parasitologia , Alemanha/epidemiologia , Fígado/parasitologia , Fígado/patologia , Reação em Cadeia da Polimerase , Suínos , Doenças dos Suínos/parasitologiaRESUMO
BACKGROUND: It is important to understand the mechanisms by which the cells integrate signals from different receptors. Several lines of evidence implicate epidermal growth factor (EGF) receptor (EGFR) in the pathophysiology of hepatocarcinomas. Data also suggest a role of prostaglandins in some of these tumours, through their receptors of the G protein-coupled receptor (GPCR) family. In this study we have investigated mechanisms of interaction between signalling from prostaglandin receptors and EGFR in hepatocarcinoma cells. METHODS: The rat hepatocarcinoma cell line MH1C1 and normal rat hepatocytes in primary culture were stimulated with EGF or prostaglandin E2 (PGE2) and in some experiments also PGF2α. DNA synthesis was determined by incorporation of radiolabelled thymidine into DNA, phosphorylation of proteins in signalling pathways was assessed by Western blotting, mRNA expression of prostaglandin receptors was determined using qRT-PCR, accumulation of inositol phosphates was measured by incorporation of radiolabelled inositol, and cAMP was determined by radioimmunoassay. RESULTS: In the MH1C1 hepatocarcinoma cells, stimulation with PGE2 or PGF2α caused phosphorylation of the EGFR, Akt, and ERK, which could be blocked by the EGFR tyrosine kinase inhibitor gefitinib. This did not occur in primary hepatocytes. qRT-PCR revealed expression of EP1, EP4, and FP receptor mRNA in MH1C1 cells. PGE2 stimulated accumulation of inositol phosphates but not cAMP in these cells, suggesting signalling via PLCß. While pretreatment with EP1 and EP4 receptor antagonists did not inhibit the effect of PGE2, pretreatment with an FP receptor antagonist blocked the phosphorylation of EGFR, Akt and ERK. Further studies suggested that the PGE2-induced signal was mediated via Ca2+ release and not PKC activation, and that it proceeded through Src and shedding of membrane-bound EGFR ligand precursors by proteinases of the ADAM family. CONCLUSION: The results indicate that in MH1C1 cells, unlike normal hepatocytes, PGE2 activates the MEK/ERK and PI3K/Akt pathways by transactivation of the EGFR, thus diversifying the GPCR-mediated signal. The data also suggest that the underlying mechanisms in these cells involve FP receptors, PLCß, Ca2+, Src, and proteinase-mediated release of membrane-associated EGFR ligand(s).
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Carcinoma Hepatocelular , Dinoprostona/administração & dosagem , Fator de Crescimento Epidérmico/administração & dosagem , Receptores ErbB , Neoplasias Hepáticas , Animais , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Dinoprostona/metabolismo , Fator de Crescimento Epidérmico/metabolismo , Receptores ErbB/genética , Receptores ErbB/metabolismo , Gefitinibe , Regulação Neoplásica da Expressão Gênica , Hepatócitos/citologia , Hepatócitos/efeitos dos fármacos , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação , Inibidores de Proteínas Quinases/administração & dosagem , Proteínas Proto-Oncogênicas c-akt/metabolismo , Quinazolinas/administração & dosagem , Ratos , Transdução de Sinais/efeitos dos fármacosRESUMO
Individuals with autism spectrum disorder (ASD) often fail to attach context to their memories and are specifically impaired in processing social aspects of contextual information. The aim of the present study was to investigate the modulatory influence of social vs. non-social context on neural mechanisms during encoding in ASD. Using event-related fMRI, 13 boys with ASD and 13 typically developing boys comparable for age and IQ were investigated during encoding of neutral objects presented either with a social (faces) or a non-social (houses) context. A memory paradigm was then applied to identify brain activation patterns associated with encoding of subsequently recollected versus non-recollected objects. On the behavioural level, no significant between-group differences emerged. In particular, no differential effects of context on memory performance were observed. Neurally, however, context-specific group differences were observed in several brain regions. During encoding of subsequently recollected objects presented with a face, ASD subjects (compared to controls) showed reduced neural activation in the bilateral inferior frontal gyrus, bilateral middle frontal gyrus and right inferior parietal lobule. Neural activation in the right inferior frontal gyrus was positively correlated with memory performance in controls, but negatively in ASD individuals. During encoding of subsequently non-recollected objects presented in the non-social context, ASD subjects showed increased activation in the dorsal MPFC. Our findings suggest that in ASD subjects, fronto-parietal brain regions subserving memory formation and the association of contextual information are activated atypically when a social context is presented at encoding. The data add to findings from related research fields indicating that in ASD, socioemotional impairment extends into domains beyond social cognition. Increased activation in the dorsal MPFC in ASD individuals might reflect supervisory cognitive processes related to the suppression of a distracting non-social context.
Assuntos
Mapeamento Encefálico , Encéfalo/fisiopatologia , Transtornos Globais do Desenvolvimento Infantil , Comportamento Social , Percepção Social , Adolescente , Análise de Variância , Encéfalo/irrigação sanguínea , Encéfalo/patologia , Criança , Transtornos Globais do Desenvolvimento Infantil/patologia , Transtornos Globais do Desenvolvimento Infantil/fisiopatologia , Transtornos Globais do Desenvolvimento Infantil/psicologia , Lateralidade Funcional , Humanos , Processamento de Imagem Assistida por Computador , Inteligência , Imageamento por Ressonância Magnética , Masculino , Rememoração Mental/fisiologia , Testes Neuropsicológicos , Oxigênio/sangue , Reconhecimento Visual de Modelos/fisiologia , Estimulação Luminosa , Tempo de Reação/fisiologia , Estatística como AssuntoRESUMO
BACKGROUND: Neurotensin has been found to promote colon carcinogenesis in rats and mice, and proliferation of human colon carcinoma cell lines, but the mechanisms involved are not clear. We have examined signalling pathways activated by neurotensin in colorectal and pancreatic carcinoma cells. METHODS: Colon carcinoma cell lines HCT116 and HT29 and pancreatic adenocarcinoma cell line Panc-1 were cultured and stimulated with neurotensin or epidermal growth factor (EGF). DNA synthesis was determined by incorporation of radiolabelled thymidine into DNA. Levels and phosphorylation of proteins in signalling pathways were assessed by Western blotting. RESULTS: Neurotensin stimulated the phosphorylation of both extracellular signal-regulated kinase (ERK) and Akt in all three cell lines, but apparently did so through different pathways. In Panc-1 cells, neurotensin-induced phosphorylation of ERK, but not Akt, was dependent on protein kinase C (PKC), whereas an inhibitor of the ß-isoform of phosphoinositide 3-kinase (PI3K), TGX221, abolished neurotensin-induced Akt phosphorylation in these cells, and there was no evidence of EGF receptor (EGFR) transactivation. In HT29 cells, in contrast, the EGFR tyrosine kinase inhibitor gefitinib blocked neurotensin-stimulated phosphorylation of both ERK and Akt, indicating transactivation of EGFR, independently of PKC. In HCT116 cells, neurotensin induced both a PKC-dependent phosphorylation of ERK and a metalloproteinase-mediated transactivation of EGFR that was associated with a gefitinib-sensitive phosphorylation of the downstream adaptor protein Shc. The activation of Akt was also inhibited by gefitinib, but only partly, suggesting a mechanism in addition to EGFR transactivation. Inhibition of PKC blocked neurotensin-induced DNA synthesis in HCT116 cells. CONCLUSIONS: While acting predominantly through PKC in Panc-1 cells and via EGFR transactivation in HT29 cells, neurotensin used both these pathways in HCT116 cells. In these cells, neurotensin-induced activation of ERK and stimulation of DNA synthesis was PKC-dependent, whereas activation of the PI3K/Akt pathway was mediated by stimulation of metalloproteinases and subsequent transactivation of the EGFR. Thus, the data show that the signalling mechanisms mediating the effects of neurotensin involve multiple pathways and are cell-dependent.