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1.
Klin Lab Diagn ; 67(11): 640-646, 2022 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-36398772

RESUMO

The possibility of the preoperative level of 42 indicators characterizing the cellular composition and metabolism in blood of patients with stage III lung adenocarcinoma (AC) to predict their relapse-free survival was studied. Blood samples of 451 patients with newly diagnosed AK stage III after their surgical treatment (resection volume - R0) have been investigated. The duration of the relapse-free period (period of observation - 1 year), cellular composition of the blood, concentration of C-RP, albumin, Cyfra 21-1 antigens, SCC, TPA, chemokines CXCL5, CXCL8, pyruvate kinase TuM2 PK isoenzyme, HIF-1α and hyaluronic acid in blood serum so as the proportion of blood cells with CXCR1 and CXCR2, CD44V6 receptors in blood serum were measured. To determine the dependence of the duration of the relapse-free period after the treatment on the observation time, Kaplan-Meier graphs were built. The relationship between the determined parameters and survival was judged using single- and multi-factor Cox proportional hazard models. Comparison of groups with different risk of AK recurrence was performed using the Log Rank test and χ2. The assessment of the predictive information content of laboratory tests was carried out using ROC analysis. It was shown that the concentration of monocytes, eosinophilic leukocytes, the relative quantity of lymphocytes with CXCR1 receptor, the level of Cyfra 21-1 before surgical treatment were associated with the duration of the relapse-free period. A regression equation was compiled, which included the level of Cyfra 21-1, relative content of lymphocytes with CXCR1, and the eosinophilic leukocytes / monocytes ratio. Based on the threshold value Y=0,597, a Kaplan-Meier plot of patient survival was built and the results of it correspond to the TNM stratification. The prognostic sensitivity of the results of the equation - 85,7%, the specificity - 94,7%.


Assuntos
Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/cirurgia , Neoplasias Pulmonares/patologia , Biomarcadores Tumorais , Recidiva Local de Neoplasia , Adenocarcinoma de Pulmão/cirurgia
2.
Herz ; 46(4): 342-351, 2021 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-32632550

RESUMO

Routine determination of troponin levels is recommended for all patients with acute ischemic stroke. In 20-55% of these patients the troponin levels are elevated, which may be caused by ischemic as well as non-ischemic myocardial damage and particularly neurocardiogenic myocardial damage. In patients with acute ischemic stroke, the prevalence of previously unknown coronary heart disease is reported to be up to 27% and is prognostically relevant for these patients; however, relevant coronary stenoses are less frequently detected in stroke patients with troponin elevation compared to patients with non-ST elevation myocardial infarction. The risk of secondary intracerebral hemorrhage due to the necessity for dual platelet aggregation inhibition illustrates the challenging indication for invasive coronary diagnostics and revascularization. Therefore, a diagnostic work-up and interdisciplinary risk evaluation appropriate to the urgency are necessary in order to be able to determine a reasonable treatment approach with timing of the intervention, type and duration of blood thinning. In addition to conventional examination methods, multimodal cardiac imaging is increasingly used for this purpose. This review article aims to provide a pragmatic and clinically oriented approach to diagnostic and therapeutic procedures, taking into account the available evidence.


Assuntos
Isquemia Encefálica , AVC Isquêmico , Infarto do Miocárdio , Acidente Vascular Cerebral , Humanos , Acidente Vascular Cerebral/diagnóstico , Troponina
3.
J Virol ; 90(14): 6557-6572, 2016 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-27170749

RESUMO

UNLABELLED: Vaccinia virus (VACV) keratitis is a serious complication following smallpox vaccination and can lead to blindness. The pathological mechanisms involved in ocular VACV infection are poorly understood. Previous studies have used rabbits, but the lack of immune reagents and transgenic or knockout animals makes them less suitable for mechanistic studies. We report that infection of C57BL/6 mice with 1 × 10(7) PFU of vaccinia virus strain WR results in blepharitis, corneal neovascularization, and stromal keratitis. The DryVax strain of VACV was completely attenuated. Infection required corneal scarification and replication-competent virus, and the severity of ocular disease was similar in 4- to 6-week-old and 1-year-old mice. Viral titers peaked at approximately 1 × 10(6) PFU on day 5 postinfection, and virus had not cleared by day 13 postinfection. Neutrophils were found in the peripheral cornea on day 1 after infection and then declined, followed by infiltration of both CD4(+) and CD8(+) T cells, which remained peripheral throughout the infection. Blood vessel growth extended 2 to 5 mm into the cornea from the limbus. Infection of CD4(-/-), CD8(-/-), or antibody-depleted mice resulted in similar disease severity and corneal clouding, indicating that both T-cell subsets were involved in the immunopathological response. Depletion of both CD4(+) and CD8(+) T cells resulted in significantly more severe disease and failure to clear the virus. On the basis of our results, the pathology of VACV keratitis is significantly different from that of herpes simplex virus keratitis. Further studies are likely to reveal novel information regarding virulence and immune responses to viral ocular infection. IMPORTANCE: Potentially blinding eye infections can occur after vaccination for smallpox. Very little is known about the pathological mechanisms that are involved, and the information that is available was generated using rabbit models. The lack of immunological reagents for rabbits makes such studies difficult. We characterized a mouse model of vaccinia virus ocular disease using C57BL/6 mice and strain WR and show that both CD4(+) and CD8(+) T-cell subsets play a role in the blinding eye disease and in controlling virus replication. On the basis of these results, vaccinia virus keratitis is significantly different from herpes simplex virus keratitis, and further studies using this model should generate novel insights into immunopathological responses to viral ocular infection.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Doenças da Córnea/imunologia , Vaccinia virus/imunologia , Vacínia/imunologia , Replicação Viral/imunologia , Animais , Linfócitos T CD4-Positivos/virologia , Linfócitos T CD8-Positivos/virologia , Doenças da Córnea/virologia , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Coelhos , Vacinação , Vacínia/virologia
4.
Orthopade ; 46(6): 541-556, 2017 Jun.
Artigo em Alemão | MEDLINE | ID: mdl-28534215

RESUMO

Acute haematogenous osteomyelitis (AHO) in children is a severe condition. A delay in diagnosis and insufficient treatment may result in deformities, chronicity and sepsis. Therefore a structured diagnostic workup has to be followed in order to diagnose or rule out osteomyelitis. To identify the causative agent for targeted antibiotic treatment, a bone biopsy or puncture should be performed. However, approximately 25% of cases are culture-negative even after biopsy. The knowledge of the typical age-dependent bacterial spectrum is essential for empirical antibiotic therapy. The principal causative organism is Staphylococcus aureus. Surgery is not routinely required in paediatric acute osteomyelitis but surgical intervention is indicated if an abscess is detected. Secondary septic arthritis is a serious complication which has to be treated immediately by surgical intervention. Nevertheless, complete regeneration can be expected in up to 80% of children with AHO.


Assuntos
Algoritmos , Bacteriemia/diagnóstico , Bacteriemia/terapia , Osteomielite/diagnóstico , Osteomielite/terapia , Infecções Estafilocócicas/diagnóstico , Infecções Estafilocócicas/terapia , Abscesso/classificação , Abscesso/diagnóstico , Abscesso/patologia , Abscesso/terapia , Doença Aguda , Adolescente , Antibacterianos/uso terapêutico , Artrite Infecciosa/classificação , Artrite Infecciosa/diagnóstico , Artrite Infecciosa/patologia , Artrite Infecciosa/terapia , Artrocentese , Bacteriemia/classificação , Bacteriemia/patologia , Biópsia , Osso e Ossos/patologia , Criança , Pré-Escolar , Terapia Combinada , Diagnóstico Tardio , Intervenção Médica Precoce , Feminino , Seguimentos , Humanos , Lactente , Recém-Nascido , Imageamento por Ressonância Magnética , Masculino , Osteomielite/classificação , Osteomielite/patologia , Infecções Estafilocócicas/classificação , Infecções Estafilocócicas/patologia
5.
Orthopade ; 44(11): 917-26, 2015 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-26489825

RESUMO

Congenital hip dysplasia and hip dislocation are relatively common pathological conditions of the musculoskeletal system in infants. An early and certain diagnosis can now be achieved by sonographic hip screening within the framework of screening examination programs. This early diagnostic procedure in infants is essential particularly for a conservative treatment strategy. Therefore, apart from possessing in-depth knowledge, training of the examiner in specialist courses is of central importance. This article presents an overview of the entity of congenital hip dysplasia and hip dislocation, the diagnostics and treatment with special emphasis on recent developments.


Assuntos
Luxação Congênita de Quadril/diagnóstico , Luxação Congênita de Quadril/terapia , Programas de Rastreamento/métodos , Exame Físico/métodos , Ultrassonografia/métodos , Artroplastia/métodos , Terapia Combinada , Diagnóstico Precoce , Humanos , Recém-Nascido , Triagem Neonatal/métodos , Procedimentos de Cirurgia Plástica/métodos
6.
Knee Surg Sports Traumatol Arthrosc ; 19(2): 292-5, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20563553

RESUMO

Degeneration of the acromioclavicular joint (AC) often causes impaired shoulder function and pain. Its infiltration results in reportedly beneficial short-term effects. Misplacement of infiltrations is observed in high numbers. A previous study showed high accuracy of infiltrations of one surgeon comparing conventional palpation technique to ultrasound guidance. This study evaluates if ultrasound-guided AC joint infiltration is feasible for therapists of different levels of experience and if the accuracy can be increased. One hundred and twenty AC joints of 60 cadavers were enrolled into a prospective, randomized observer-blinded study. Six therapists of three different levels of experience infiltrated 20 AC joints each. Half of them were infiltrated after palpation of the joint space, half of them were ultrasound-guided infiltrated. Controls were performed pre- and post-infiltration by an independent radiologist. In total, accurate infiltration was observed in 70%. In 25%, misplacement of the infiltration was recorded in the palpation-, in 2% in the ultrasound- and in 3% in both groups. The difference between the two groups was significant (P = 0.009). Ultrasound-guided infiltration to the AC joint is significantly more accurate than conventional palpation technique. This method is simple, efficient and can be applied by therapists of all levels of experience.


Assuntos
Articulação Acromioclavicular/diagnóstico por imagem , Articulação Acromioclavicular/patologia , Injeções Intra-Articulares/métodos , Ultrassonografia de Intervenção/métodos , Idoso , Idoso de 80 Anos ou mais , Cadáver , Competência Clínica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Palpação , Estudos Prospectivos , Método Simples-Cego
8.
Osteoarthritis Cartilage ; 18(2): 240-8, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19800998

RESUMO

OBJECTIVE: Sialic acids frequently occur at the terminal positions of glycoprotein N-glycans present at chondrocyte surfaces or in the cartilage matrix. Sialic acids are transferred to glycoproteins in either alpha-2,3 or alpha-2,6 linkage by specific sialyltransferases (SiaTs) and can potentially affect cell functions and cell-matrix interactions. The present study aimed to assess the relationship between the expression of the human chondrocyte phenotype and the sialylation of chondrocyte glycoprotein N-glycans. METHODS: The transcription of 5 SiaT was quantified using real-time Reverse transcription polymerase chain reaction (RT-PCR) assays. N-glycan analysis was performed using LC-ESI-MS. Primary human chondrocytes were cultured in monolayer or alginate beads and compared to the chondrocyte cell lines C-28/I2 and SW1353. In addition, effects of interleukin-1beta (IL-1beta) or tumour necrosis factor-alpha (TNF-alpha) on primary cells were assessed. RESULTS: Primary human chondrocytes predominantly express alpha-2,6-specific SiaTs and accordingly, alpha-2,6-linked sialic acid residues in glycoprotein N-glycans. In contrast, the preponderance of alpha-2,3-linked sialyl residues and, correspondingly, reduced levels of alpha-2,6-specific SiaTs are associated with the altered chondrocyte phenotype of C-28/I2 and SW1353 cells. Importantly, a considerable shift towards alpha-2,3-linked sialic acids and alpha-2,3-specific SiaT mRNA levels occurred in primary chondrocytes treated with IL-1beta or tumour necrosis factor-alpha (TNF-alpha). CONCLUSION: The expression of the differentiated chondrocyte phenotype is linked to the ratio of alpha-2,6- to alpha-2,3-linked sialic acids in chondrocyte glycoprotein N-glycans. A shift towards altered sialylation might contribute to impaired cell-matrix interactions in disease conditions.


Assuntos
Condrócitos/metabolismo , Glicoproteínas/química , Sialiltransferases/metabolismo , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Condrócitos/efeitos dos fármacos , Citocinas/farmacologia , Expressão Gênica , Humanos , Interleucina-1beta/farmacologia , Fenótipo , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Sialiltransferases/química , Sialiltransferases/genética , Fator de Necrose Tumoral alfa/farmacologia
9.
Gut ; 58(7): 949-63, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18829980

RESUMO

BACKGROUND AND AIMS: Emerging evidence suggests that highly treatment-resistant tumour-initiating cells (TICs) play a central role in the pathogenesis of pancreatic cancer. Tumour necrosis factor-related apoptosis-inducing ligand (TRAIL) is considered to be a novel anticancer agent; however, recent studies have shown that many pancreatic cancer cells are resistant to apoptosis induction by TRAIL due to TRAIL-activated nuclear factor-kappaB (NF-kappaB) signalling. Several chemopreventive agents are able to inhibit NF-kappaB, and favourable results have been obtained--for example, for the broccoli compound sulforaphane-in preventing metastasis in clinical studies. The aim of the study was to identify TICs in pancreatic carcinoma for analysis of resistance mechanisms and for definition of sensitising agents. METHODS: TICs were defined by expression patterns of a CD44(+)/CD24(-), CD44(+)/CD24(+) or CD44(+)/CD133(+) phenotype and correlation to growth in immunodeficient mice, differentiation grade, clonogenic growth, sphere formation, aldehyde dehydrogenase (ALDH) activity and therapy resistance. RESULTS: Mechanistically, specific binding of transcriptionally active cRel-containing NF-kappaB complexes in TICs was observed. Sulforaphane prevented NF-kappaB binding, downregulated apoptosis inhibitors and induced apoptosis, together with prevention of clonogenicity. Gemcitabine, the chemopreventive agents resveratrol and wogonin, and the death ligand TRAIL were less effective. In a xenograft model, sulforaphane strongly blocked tumour growth and angiogenesis, while combination with TRAIL had an additive effect without obvious cytotoxicity in normal cells. Freshly isolated patient tumour cells expressing markers for TICs could be sensitised by sulforaphane for TRAIL-induced cytotoxicity. CONCLUSION: The data provide new insights into resistance mechanisms of TICs and suggest the combination of sulforaphane with TRAIL as a promising strategy for targeting of pancreatic TICs.


Assuntos
Anticarcinógenos/uso terapêutico , Apoptose/efeitos dos fármacos , NF-kappa B/antagonistas & inibidores , Neoplasias Pancreáticas/prevenção & controle , Tiocianatos/uso terapêutico , Animais , Células Cultivadas , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Isotiocianatos , Camundongos , Camundongos Nus , NF-kappa B/metabolismo , Pâncreas/metabolismo , Neoplasias Pancreáticas/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Sulfóxidos , Ligante Indutor de Apoptose Relacionado a TNF/genética , Ligante Indutor de Apoptose Relacionado a TNF/metabolismo
10.
Anal Biochem ; 385(1): 13-9, 2009 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-19026979

RESUMO

Release of non-protein bound iron plays an important role in the toxicity inflicted by chemotherapy in cancer patients. Since large variations have been described for different methods measuring non-transferrin bound iron (NTBI), we aimed to obtain more accurate values. After binding to the chelator nitrilotriacetic acid disodium salt (NTA) and ultrafiltration, the NTBI can be measured spectrophotometrically by the addition of thioglycolic acid (TGA) and baptophenanthroline disulfonic acid (BPT). Results demonstrated that NTBI values increased with NTA concentration. In samples incubated with 80 mM NTA, >5-fold higher NTBI values were found compared to using 10 mM NTA. Optimal concentration of NTA was established by additions of iron to serum with known latent iron-binding capacity (LIBC). Iron addition curves showed that NTBI could be measured starting from the LIBC of the serum with optimal yield after incubation with 4 mM NTA in 5 mM Tris-HCl pH 6.5, with 3mM TGA and 6.2 mM BPT for the colour reaction. The results showed excellent correlation with 195 samples measured also by HPLC. For the spectrophotometric method, significantly higher NTBI values were measured in patient samples with maximal iron saturation compared to patients with lower iron saturation.


Assuntos
Quelantes/farmacologia , Ferro/sangue , Sítios de Ligação , Quelantes/química , Cromatografia Líquida de Alta Pressão , Humanos , Ferro/metabolismo , Ácido Nitrilotriacético/química , Ácido Nitrilotriacético/farmacologia , Fenantrolinas/química , Reprodutibilidade dos Testes , Sais/química , Sensibilidade e Especificidade , Compostos de Sódio/química , Compostos de Sódio/farmacologia , Ácidos Sulfônicos/química , Tioglicolatos/química , Transferrina/metabolismo , Ultrafiltração
11.
Phys Med Biol ; 64(5): 055004, 2019 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-30654339

RESUMO

The outcome of preclinical imaging studies are enhanced by simultaneous, high-resolution anatomical and molecular data, which advanced PET/MRI systems provide. Nevertheless, mapping of neuroreceptors and accurate quantification of PET tracer distribution in mouse brains is not trivial. The restricted spatial resolution and sensitivity in commercial animal PET systems limits the image quality and the quantification accuracy. We are currently developing a PET/MRI system dedicated for mouse brain studies. The PET system will offer system dimensions of approx. 30 mm in diameter and an axial length of more than 38 mm. This work discusses two system geometries including their associated block detectors. Both configurations were based on a dual layer offset structure with small crystals sizes, in the order of 1  × 1 × 4/6 mm3, to provide discrete depth of interaction information. The detector for configuration 'A' was based on a 4 × 4 silicon photomultiplier (SiPM) array attached to an optical diffusor, and a 12 × 12 as well as a 9 × 11 LSO crystal array, to achieve optimal system sensitivity. This configuration was evaluated by a double layer of 12 × 12 crystals. Configuration 'B' was composed of three 2 × 2 SiPM arrays equipped with a 1 mm diffusor to read out an LSO stack of 20  × 6 and 19  × 5 individual crystals. The average peak-to-valley ratio of the inner/outer layer was 3.5/3.6 for detector 'A', and 3.4/2.8 for detector 'B'. The average full width at half maximum (FWHM) energy resolution of the block detectors were 22.24% ± 3.36% for 'A' and 30.67% ± 5.37% for 'B'. The FWHM of the full block timing resolution of the inner/outer layer was 1.4 ns/1.2 ns for detector 'A' and 1.8 ns/1.4 ns for 'B'. The performance of the crystal position profile, the energy, and timing resolution indicate that configuration 'A' is more appropriate for a mouse brain PET/MRI system.


Assuntos
Encéfalo/diagnóstico por imagem , Imageamento por Ressonância Magnética/instrumentação , Tomografia por Emissão de Pósitrons/instrumentação , Animais , Desenho de Equipamento , Camundongos , Silício
12.
Wien Klin Wochenschr ; 131(23-24): 627-629, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31641858

RESUMO

Correction to: Wien Klin Wochenschr 2019 https://doi.org/10.1007/s00508-019-01541-8The original version of this article unfortunately contained a mistake. The presentation of Tab. 4 was incorrect. The corrected table is given below.The original article has been ….

13.
Plant Biol (Stuttg) ; 21(4): 677-687, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30659728

RESUMO

Climate change is driving movements of many plants beyond, as well as within, their current distributional ranges. Even migrant plants moving within their current range may experience different plant-soil feedbacks (PSF) because of divergent nonlocal biotic soil conditions. Yet, our understanding to what extent soil biotic conditions can affect the performance of within-range migrant plants is still very limited. We assessed the emergence and growth of migrant forest herbs (Milium effusum and Stachys sylvatica) using soils and seeds collected along a 1,700 km latitudinal gradient across Europe. Soil biota were manipulated through four soil treatments, i.e. unsterilized control soil (PSFUS ), sterilized soil (PSFS ), sterilized soil inoculated with unsterilized home soil (PSFS+HI ) and sterilized soil inoculated with unsterilized foreign soil (PSFS+FI , expected to occur when both plants and soil biota track climate change). Compared to PSFS , PSFUS had negative effects on the growth but not emergence of both species, while PSFS+FI only affected S. sylvatica across all seed provenances. When considering seed origin, seedling emergence and growth responses to nonlocal soils depended on soil biotic conditions. Specifically, the home-away distance effect on seedling emergence differed between the four treatments, and significant responses to chemistry either disappeared (M. effusum) or changed (S. sylvatica) from PSFUS to PSFS . Soil biota emerge as an important driver of the estimated plant migration success. Our results of the effects of soil microorganisms on plant establishment provide relevant information for predictions of the distribution and dynamics of plant species in a changing climate.


Assuntos
Florestas , Poaceae/crescimento & desenvolvimento , Solo , Stachys/crescimento & desenvolvimento , Ecossistema , Retroalimentação Fisiológica , Microbiologia do Solo
14.
Transplant Proc ; 40(2): 641-3, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18374151

RESUMO

OBJECTIVES: There are differences in symptoms, risk stratification, and efficacy of pharmacological treatments between men and women with coronary artery disease (CAD). The results of clinical studies of cell therapy in CAD patients are mixed. The relevance of sex to response to cell therapy is unknown. We investigated sex-based differences in response to bone marrow mononuclear cells (BM-MNCs) in atherosclerotic apoliproprotein E-knockout (ApoE -/-) mice. METHODS: Twenty-three male and 27 female ApoE -/- mice fed on a high-fat diet received four intravenous BM-MNC injections (C57BL6/J mice) starting at 14 weeks of age; male or female BM-MNCs were administered. Thirteen male and 20 female atherosclerotic ApoE -/- mice received vehicle. Aortic plaque burden (%), recipient bone marrow progenitor cell profiles (FACS-LSR II, FlowJo) and 22 circulating cytokine panel (LINCOplex) were quantified and analyzed statistically (SSPS, P < or 5). RESULTS: Quantitative and semiquantitative results are presented. Increased G-CSF levels correlated with plaque reduction (r = -.86, P = .0004). G-CSF was clustered with IL-15. CONCLUSIONS: Female but not male BM-MNCs exhibited atheroprotection in male atherosclerotic ApoE -/- mice. Plaque lesions did not attenuate atherosclerosis in female ApoE -/- mice with BM-MNCs of either donor sex. An increase in regulatory and in Th2-type response may be required for atheroprotection. Sex-based differences in vascular repair have implications for cell therapy trials in CAD.


Assuntos
Apolipoproteínas E/deficiência , Aterosclerose/prevenção & controle , Citocinas/fisiologia , Leucócitos Mononucleares/transplante , Células Th2/imunologia , Animais , Transplante de Medula Óssea , Feminino , Masculino , Camundongos , Camundongos Knockout , Caracteres Sexuais
15.
Phys Med Biol ; 63(4): 045022, 2018 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-29384502

RESUMO

This study depicts the evaluation of a SiPM detector with depth of interaction (DOI) capability via a dual-sided readout that is suitable for high-resolution positron emission tomography and magnetic resonance (PET/MR) imaging. Two different 12 × 12 pixelated LSO scintillator arrays with a crystal pitch of 1.60 mm are examined. One array is 20 mm-long with a crystal separation by the specular reflector Vikuiti enhanced specular reflector (ESR), and the other one is 18 mm-long and separated by the diffuse reflector Lumirror E60 (E60). An improvement in energy resolution from 22.6% to 15.5% for the scintillator array with the E60 reflector is achieved by taking a nonlinear light collection correction into account. The results are FWHM energy resolutions of 14.0% and 15.5%, average FWHM DOI resolutions of 2.96 mm and 1.83 mm, and FWHM coincidence resolving times of 1.09 ns and 1.48 ns for the scintillator array with the ESR and that with the E60 reflector, respectively. The measured DOI signal ratios need to be assigned to an interaction depth inside the scintillator crystal. A linear and a nonlinear method, using the intrinsic scintillator radiation from lutetium, are implemented for an easy to apply calibration and are compared to the conventional method, which exploits a setup with an externally collimated radiation beam. The deviation between the DOI functions of the linear or nonlinear method and the conventional method is determined. The resulting average of differences in DOI positions is 0.67 mm and 0.45 mm for the nonlinear calibration method for the scintillator array with the ESR and with the E60 reflector, respectively; Whereas the linear calibration method results in 0.51 mm and 0.32 mm for the scintillator array with the ESR and the E60 reflector, respectively; and is, due to its simplicity, also applicable in assembled detector systems.


Assuntos
Tomografia por Emissão de Pósitrons/normas , Calibragem , Lutécio/química , Tomografia por Emissão de Pósitrons/instrumentação
16.
Plant Biol (Stuttg) ; 20(3): 619-626, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29323793

RESUMO

Elevated atmospheric input of nitrogen (N) is currently affecting plant biodiversity and ecosystem functioning. The growth and survival of numerous plant species is known to respond strongly to N fertilisation. Yet, few studies have assessed the effects of N deposition on seed quality and reproductive performance, which is an important life-history stage of plants. Here we address this knowledge gap by assessing the effects of atmospheric N deposition on seed quality of the ancient forest herb Anemone nemorosa using two complementary approaches. By taking advantage of the wide spatiotemporal variation in N deposition rates in pan-European temperate and boreal forests over 2 years, we detected positive effects of N deposition on the N concentration (percentage N per unit seed mass, increased from 2.8% to 4.1%) and N content (total N mass per seed more than doubled) of A. nemorosa seeds. In a complementary experiment, we applied ammonium nitrate to aboveground plant tissues and the soil surface to determine whether dissolved N sources in precipitation could be incorporated into seeds. Although the addition of N to leaves and the soil surface had no effect, a concentrated N solution applied to petals during anthesis resulted in increased seed mass, seed N concentration and N content. Our results demonstrate that N deposition on the petals enhances bioaccumulation of N in the seeds of A. nemorosa. Enhanced atmospheric inputs of N can thus not only affect growth and population dynamics via root or canopy uptake, but can also influence seed quality and reproduction via intake through the inflorescences.


Assuntos
Anemone/fisiologia , Flores/metabolismo , Nitrogênio/metabolismo , Sementes/fisiologia , Anemone/química , Anemone/metabolismo , Atmosfera , Clima , Europa (Continente) , Flores/química , Florestas , Nitrogênio/análise , Reprodução/fisiologia
17.
Tissue Cell ; 39(6): 399-414, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17881026

RESUMO

Cephalic sensory organs (CSOs) are specialised structures in the head region of adult Opisthobranchia involved in perception of different stimuli. The gross morphology of these organs differs considerably among taxa. The current study aims at describing the cellular morphology of the CSOs in order to reveal cellular patterns, especially of sensory epithelia, common for opisthobranchs. Transmission electron microscopy was used to characterise the fine structure of the organs and to compare the CSOs of four different opisthobranch species. The cellular composition of the sensory system is conserved among taxa. The epidermal cells in sensory regions are always columnar and ciliated cells are frequently apparent. The sensory cells are primary receptors arranged in subepidermal cell clusters. They extend dendrites which penetrate the epithelium and reach the surface. Some of the dendrites bear cilia, whereas others only build a small protuberance. Processing of sensory information takes place in the peripheral glomeruli of all species. Moreover, few taxa possess additional peripheral ganglia at the base of their CSOs. The results of the present study might support other investigations indicating that the posterior CSOs are primarily involved in distance chemoreception, whereas the anterior CSOs might be used for contact chemoreception and mechanoreception.


Assuntos
Gastrópodes/ultraestrutura , Órgãos dos Sentidos/ultraestrutura , Animais , Epitélio , Cabeça , Microscopia Eletrônica de Transmissão
18.
Chirurg ; 78(9): 802-9, 2007 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-17680231

RESUMO

Macroscopic and microscopic complete resection, i.e. R0 resection, is a basic principle of oncologic hepatopancreatobiliary (HPB) surgery. The reported R1 rates for different HPB tumor entities vary considerably, most likely because of ambiguities in the exact definition of R1 resection and the lack of standardized histopathologic examination and reporting. R1 resections can be interpreted as technical/surgical failure (e.g. for small, peripherally located liver tumors). In most cases, however, R1 resections are determined by the anatomic location of the tumor and the growth pattern (e.g. pancreatic cancer with perineural invasion). R0 resections have been identified as positive predictive markers for several HPB tumors (in comparison to R1 resection). Therefore HPB surgeons should always aim at macroscopic and microscopic complete resections. Nonetheless, R1 resections often provide an advantage over no resection with respect to survival and quality of life in patients with these tumors.


Assuntos
Ampola Hepatopancreática , Neoplasias dos Ductos Biliares/cirurgia , Ductos Biliares Intra-Hepáticos , Carcinoma Hepatocelular/cirurgia , Colangiocarcinoma/cirurgia , Neoplasias do Ducto Colédoco/cirurgia , Neoplasias da Vesícula Biliar/cirurgia , Ducto Hepático Comum , Neoplasias Hepáticas/cirurgia , Neoplasia Residual/cirurgia , Neoplasias Pancreáticas/cirurgia , Ampola Hepatopancreática/patologia , Neoplasias dos Ductos Biliares/mortalidade , Neoplasias dos Ductos Biliares/patologia , Ductos Biliares Intra-Hepáticos/patologia , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/patologia , Colangiocarcinoma/mortalidade , Colangiocarcinoma/patologia , Neoplasias do Ducto Colédoco/mortalidade , Neoplasias do Ducto Colédoco/patologia , Vesícula Biliar/patologia , Neoplasias da Vesícula Biliar/mortalidade , Neoplasias da Vesícula Biliar/patologia , Ducto Hepático Comum/patologia , Humanos , Tumor de Klatskin/mortalidade , Tumor de Klatskin/patologia , Tumor de Klatskin/cirurgia , Fígado/patologia , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/secundário , Neoplasia Residual/mortalidade , Neoplasia Residual/patologia , Pâncreas/patologia , Neoplasias Pancreáticas/mortalidade , Neoplasias Pancreáticas/patologia , Qualidade de Vida
19.
Phys Med Biol ; 62(18): 7357-7378, 2017 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-28862997

RESUMO

Preclinical imaging benefits from simultaneous acquisition of high-resolution anatomical and molecular data. Additionally, PET/MRI systems can provide functional PET and functional MRI data. To optimize PET sensitivity, we propose a system design that fully integrates the MRI coil into the PET system. This allows positioning the scintillators near the object but requires an optimized design of the MRI coil and PET detector. It further requires a new approach in realizing the radiofrequency (RF) shielding. Thus, we propose the use of an optically transparent RF shielding material between the PET scintillator and the light sensor, suppressing the interference between both systems. We evaluated two conductive foils (ITO, 9900) and a wire mesh. The PET performance was tested on a dual-layer scintillator consisting of 12 × 12 LSO matrices, shifted by half a pitch. The pixel size was 0.9 × 0.9 mm2; the lengths were 10.0 mm and 5.0 mm, respectively. For a light sensor, we used a 4 × 4 SiPM array. The RF attenuation was measured from 320 kHz to 420 MHz using two pick-up coils. MRI-compatibility and shielding effect of the materials were evaluated with an MRI system. The average FWHM energy resolution at 511 keV of all 144 crystals of the layer next to the SiPM was deteriorated from 15.73 ± 0.24% to 16.32 ± 0.13%, 16.60 ± 0.25%, and 19.16 ± 0.21% by the ITO foil, 9900 foil, mesh material, respectively. The average peak-to-valley ratio of the PET detector changed from 5.77 ± 0.29 to 4.50 ± 0.39, 4.78 ± 0.48, 3.62 ± 0.16, respectively. The ITO, 9900, mesh attenuated the scintillation light by 11.3 ± 1.6%, 11.0 ± 1.8%, 54.3 ± 0.4%, respectively. To attenuate the RF from 20 MHz to 200 MHz, mesh performed better than copper. The results show that an RF shielding material that is sufficiently transparent for scintillation light and is MRI compatible can be obtained. This result enables the development of a fully integrated PET detector and MRI coil assembly.


Assuntos
Luz , Imageamento por Ressonância Magnética/métodos , Posicionamento do Paciente/instrumentação , Imagens de Fantasmas , Tomografia por Emissão de Pósitrons/métodos , Ondas de Rádio , Humanos
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