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1.
World J Urol ; 39(10): 3861-3866, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33866401

RESUMO

PURPOSE: The aim of this study was to assess the post biopsy infection rate, feasibility and prostate cancer (PCa) detection rate (CDR) by performing transperineal MRI-TRUS fusion biopsy of the prostate (TPBx) under local anesthesia (LA) without antibiotic prophylaxis (AP). METHODS: We prospectively screened 766 men with suspicious lesions on mpMRI, an elevated PSA level or a suspect digital examination undergoing MRI-TRUS-TPBx in LA, from May 2019 to July 2020. Patients with the need for antibiotic prophylaxis or without a PI-RADS target lesion were excluded from final analyses. We reported CDR, perioperative pain (0-10) and postoperative complications. PCa with an ISUP grade ≥ 2 was classified as clinically significant PCa (csPCa). RESULTS: We included 621 patients with a median age of 68 years (IQR 62-74), a PSA of 6.43 ng/mL (IQR 4.72-9.91) and a prostate volume of 45 cc (IQR 32-64). In median, 4 targeted (TB) (IQR 3-4) and 6 (IQR 5-7) systematic biopsies (SB) detected in combination overall 416 (67%) PCa and 324 (52%) csPCa. Overall CDR of TB for PI-RADS 3, 4 and 5 was 26%, 65% and 84%, respectively. Patients reported a median perioperative pain level of 2 (IQR 1-3). Four patients (0.6%) developed a post biopsy infection, one experienced urosepsis. CONCLUSION: Our results demonstrate that transperineal MRI-TRUS fusion-guided prostate biopsy under LA without AP is feasible, safe and well tolerated.


Assuntos
Biópsia Guiada por Imagem/métodos , Neoplasias da Próstata/patologia , Sepse/epidemiologia , Infecção da Ferida Cirúrgica/epidemiologia , Infecções Urinárias/epidemiologia , Idoso , Anestesia Local , Antibioticoprofilaxia/métodos , Endossonografia , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Imageamento por Ressonância Magnética Multiparamétrica , Períneo , Próstata/patologia , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/sangue , Neoplasias da Próstata/diagnóstico por imagem , Estudos Retrospectivos
2.
J Neurooncol ; 139(3): 583-590, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29882045

RESUMO

PURPOSE: Glioblastoma multiforme (GBM) is the most common primary brain tumor and has a very poor overall prognosis. Multimodal treatment is still inefficient and one main reason is the invasive nature of GBM cells, enabling the tumor cells to escape from the treatment area causing tumor progression. This experimental study describes the effect of low- and high-LET irradiation on the invasion of primary GBM cells with a validation in established cell systems. METHODS: Seven patient derived primary GBM as well as three established cell lines (LN229, LN18 and U87) were used in this study. Invasion was investigated using Matrigel® coated transwell chambers. Irradiation was performed with low- (X-ray) and high-LET (alpha particles) radiation. The colony formation assay was chosen to determine the corresponding alpha particle dose equivalent to the X-ray dose. RESULTS: 4 Gy X-ray irradiation increased the invasive potential of six patient derived GBM cells as well as two of the established lines. In contrast, alpha particle irradiation with an equivalent dose of 1.3 Gy did not show any effect on the invasive behavior. The findings were validated with established cell lines. CONCLUSION: Our results show that in contrast to low-LET irradiation high-LET irradiation does not enhance the invasion of established and primary glioblastoma cell lines. We therefore suggest that high-LET irradiation could become an alternative treatment option. To fully exploit the benefits of high-LET irradiation concerning the invasion of GBM further molecular studies should be performed.


Assuntos
Partículas alfa/uso terapêutico , Neoplasias Encefálicas/radioterapia , Glioblastoma/radioterapia , Terapia por Raios X , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/fisiopatologia , Sobrevivência Celular/efeitos da radiação , Células Cultivadas , Relação Dose-Resposta à Radiação , Glioblastoma/patologia , Glioblastoma/fisiopatologia , Humanos , Invasividade Neoplásica
3.
Reprod Biol Endocrinol ; 15(1): 87, 2017 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-29096644

RESUMO

BACKGROUND: Miscarriage is a common complication in pregnancy and there is still a lack of biomarkers usable in asymptomatic patients before the event occurs. Periostin (PER), whose levels rise particularly during injury or inflammation, has been shown to play an important local role in implantation and early embryonic development. As PER has been described as a biomarker in various medical conditions we intended to evaluate if changes in PER serum levels may help to identify women at risk for spontaneous abortion in the first trimester. METHODS: Women between 18 and 42 years without confounding comorbidities who conceived by IVF/ICSI and ovarian hyperstimulation were analysed in the study after informed consent. Maternal serum samples from 41 patients were assessed at the time of pregnancy testing (PT) and the following first ultrasound checkup (US). Patients were subsequently divided in two groups: (1) patients with subsequent miscarriage in the first trimester (n = 18) and (2) patients with ongoing pregnancy (n = 23), allowing for statistical analysis and investigating the change of PER levels per individual. PER levels were measured using enzyme-linked immunosorbent assay. Statistical analysis was performed using the Fisher exact and Student's t test. p ≤ 0.05 was considered to be significant. RESULTS: There was no significant difference concerning possible confounders between the two groups. We did not find any significant difference in PER levels at the time point of PT or US. By investigating the interindividual changes of PER between the two time points however, we observed that patients with a following miscarriage showed increasing levels of PER at the time point of PT compared to US in contrast to patients with an ongoing pregnancy who demonstrated a decrease in PER levels. These alterations were significant in the absolute as well as in the relative comparison. CONCLUSION: The relative expression of PER between PT and US is significantly altered in asymptomatic women with subsequent miscarriage compared to women with ongoing pregnancy. Therefore systemic PER levels might represent a potential promising biomarker for the assessment of pregnancy outcome. TRIAL REGISTRATION: Not applicable.


Assuntos
Aborto Espontâneo/sangue , Moléculas de Adesão Celular/sangue , Primeiro Trimestre da Gravidez/sangue , Adolescente , Adulto , Biomarcadores/sangue , Estudos de Casos e Controles , Feminino , Fertilização in vitro , Humanos , Gravidez , Resultado da Gravidez , Diagnóstico Pré-Natal/métodos , Injeções de Esperma Intracitoplásmicas , Adulto Jovem
4.
Nervenarzt ; 85(8): 965-75, 2014 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-25037493

RESUMO

By combining the expertise of clinical neuroscience, the aim of neuro-oncology is to optimize diagnostic planning and therapy of primary brain tumors in an interdisciplinary setting together with radio-oncology and medical oncology. High-end imaging frequently allows brain tumors to be diagnosed preoperatively with respect to tumor entity and even tumor malignancy grade. Moreover, neuroimaging is indispensable for guidance of biopsy resection and monitoring of therapy. Surgical resection of intracranial lesions with preservation of neurological function is increasingly feasible. Tools to achieve this goal are, for example neuronavigation, functional magnetic resonance imaging (fMRI), tractography, intraoperative cortical stimulation and precise intraoperative definition of tumor margins by virtue of various techniques. In addition to classical histopathological diagnosis and tumor classification, modern neuropathology is supplemented by molecular characterization of brain tumors in order to provide clinicians with prognostic and predictive (of therapy) markers, such as codeletion of chromosomes 1p and 19q in anaplastic gliomas and O6-methylguanine-DNA methyltransferase (MGMT) promoter methylation in glioblastomas. Although this is not yet individualized tumor therapy, the increasingly more detailed analysis of the molecular pathogenesis of an individual glioma will eventually lead to specific pharmacological blockade of disturbed intracellular pathways in individual patients. This article gives an overview of the state of the art of interdisciplinary neuro-oncology whereby part 1 deals with the diagnostics and surgical therapy of primary brain tumors and part 2 describes the medical therapy of primary brain tumors.


Assuntos
Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/cirurgia , Imagem Molecular/métodos , Neuroimagem/métodos , Procedimentos Neurocirúrgicos/métodos , Cirurgia Assistida por Computador/métodos , Humanos , Oncologia/métodos , Neurologia/métodos , Equipe de Assistência ao Paciente
5.
Nervenarzt ; 85(8): 976-81, 2014 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-25037494

RESUMO

By combining the expertise of clinical neuroscience, the aim of neuro-oncology is to optimize diagnostic planning and therapy of primary brain tumors in an interdisciplinary setting together with radio-oncology and medical oncology. High-end imaging frequently allows brain tumors to be diagnosed preoperatively with respect to tumor entity and even tumor malignancy grade. Moreover, neuroimaging is indispensable for guidance of biopsy resection and monitoring of therapy. Surgical resection of intracranial lesions with preservation of neurological function has become dramatically more extensive. Tools to achieve this goal are, for example neuronavigation, functional magnetic resonance imaging (fMRI), tractography, intraoperative cortical stimulation and precise intraoperative definition of tumor margins by virtue of various techniques. In addition to classical histopathological diagnosis and tumor classification, modern neuropathology is supplemented by molecular characterization of brain tumors in order to provide clinicians with prognostic and predictive (of therapy) markers, such as codeletion of chromosomes 1p and 19q in anaplastic gliomas and O6-methylguanine-DNA methyltransferase (MGMT) promoter methylation in glioblastomas. Although this is not yet individualized tumor therapy, the increasingly more detailed analysis of the molecular pathogenesis of an individual glioma will eventually lead to specific pharmacological blockade of disturbed intracellular pathways in individual patients. This article gives an overview of the state of the art of interdisciplinary neuro-oncology whereby part 1 deals with the diagnostics and surgical therapy of primary brain tumors and part 2 describes the medical therapy of primary brain tumors.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/tratamento farmacológico , Imagem Molecular/métodos , Terapia de Alvo Molecular/métodos , Humanos , Oncologia/métodos , Neurologia/métodos , Equipe de Assistência ao Paciente
6.
Mutat Res ; 753(1): 23-8, 2013 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-23416235

RESUMO

In the past few years, cold atmospheric plasma (CAP) has evolved into a new tool in the fight against nosocomial infections and antibiotic-resistant microorganisms. The products generated by the plasma-electrons, ions, reactive species and UV light-represent a 'lethal cocktail' for different kinds of pathogen, which opens up possible applications in hygiene and medicine. Nevertheless, to ensure the safe usage of CAP on skin (e.g., to treat wounds or skin diseases) several pre-clinical in vitro studies have to be performed before implementing clinical trials on humans. In the study presented here, inactivation experiments with Escherichia coli were carried out to identify the necessary plasma dosage for a 5 log reduction: with a small hand-held battery-operated CAP device, these disinfection properties were achieved after application during 30s. This and higher plasma dosages were then used to analyze the mutagenicity induced in V79 Chinese hamster cells-to furthermore define a 'safe application window'-with the HPRT (hypoxanthine-guanine phosphoribosyl transferase) mutation assay. The results show that a CAP treatment of up to 240 s and repeated treatments of 30s every 12h did not induce mutagenicity at the Hprt locus beyond naturally occurring spontaneous mutations.


Assuntos
Desinfecção/métodos , Escherichia coli/genética , Gases em Plasma/toxicidade , Esterilização/métodos , Ar , Animais , Linhagem Celular , Cricetinae , Cricetulus , Dano ao DNA , Desinfecção/instrumentação , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Hipoxantina Fosforribosiltransferase/genética , Íons , Testes de Mutagenicidade , Mutação , Espécies Reativas de Nitrogênio , Espécies Reativas de Oxigênio , Esterilização/instrumentação , Raios Ultravioleta
7.
Nat Commun ; 14(1): 7651, 2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-38030606

RESUMO

Owing to their high magnon frequencies, antiferromagnets are key materials for future high-speed spintronics. Picosecond switching of antiferromagnetic spin systems has been viewed a milestone for decades and pursued only by using ultrafast external perturbations. Here, we show that picosecond spin switching occurs spontaneously due to thermal fluctuations in the antiferromagnetic orthoferrite Sm0.7Er0.3FeO3. By analysing the correlation between the pulse-to-pulse polarisation fluctuations of two femtosecond optical probes, we extract the autocorrelation of incoherent magnon fluctuations. We observe a strong enhancement of the magnon fluctuation amplitude and the coherence time around the critical temperature of the spin reorientation transition. The spectrum shows two distinct features, one corresponding to the quasi-ferromagnetic mode and another one which has not been previously reported in pump-probe experiments. Comparison to a stochastic spin dynamics simulation reveals this new mode as smoking gun of ultrafast spontaneous spin switching within the double-well anisotropy potential.

8.
ESMO Open ; 7(5): 100566, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36055049

RESUMO

BACKGROUND: Intratumoral heterogeneity at the cellular and molecular level is a hallmark of glioblastoma (GB) that contributes to treatment resistance and poor clinical outcome. Little is known regarding epigenetic heterogeneity and intratumoral phylogeny and their implication for molecular classification and targeted therapies. PATIENTS AND METHODS: Multiple tissue biopsies (238 in total) were sampled from 56 newly-diagnosed, treatment-naive GB patients from a prospective in-house cohort and publicly available data and profiled for DNA methylation using the Illumina MethylationEPIC array. Methylation-based classification using the glioma classifier developed by Ceccarelli et al. and estimation of the MGMT promoter methylation status via the MGMT-STP27 model were carried out. In addition, copy number variations (CNVs) and phylogeny were analyzed. RESULTS: Almost half of the patients (22/56, 39%) harbored tumors composed of heterogeneous methylation subtypes. We found two predominant subtype combinations: classic-/mesenchymal-like, and mesenchymal-/pilocytic astrocytoma-like. Nine patients (16%) had tumors composed of subvolumes with and without MGMT promoter methylation, whereas 20 patients (36%) were homogeneously methylated, and 27 patients (48%) were homogeneously unmethylated. CNV analysis revealed high variations in many genes, including CDKN2A/B, EGFR, and PTEN. Phylogenetic analysis correspondingly showed a general pattern of CDKN2A/B loss and gain of EGFR, PDGFRA, and CDK4 during early stages of tumor development. CONCLUSIONS: (Epi)genetic intratumoral heterogeneity is a hallmark of GB, both at DNA methylation and CNV level. This intratumoral heterogeneity is of utmost importance for molecular classification as well as for defining therapeutic targets in this disease, as single biopsies might underestimate the true molecular diversity in a tumor.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Humanos , Glioblastoma/genética , Glioblastoma/terapia , Metilases de Modificação do DNA/genética , Enzimas Reparadoras do DNA/genética , Variações do Número de Cópias de DNA , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/terapia , Neoplasias Encefálicas/diagnóstico , Estudos Prospectivos , Filogenia , Metilação de DNA , Biópsia , Receptores ErbB
9.
Urologe A ; 59(10): 1225-1230, 2020 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-32161979

RESUMO

The perineal approach for prostate biopsy (PB) is a sterile alternative to conventional transrectal PB. Targeted local anesthesia allows perineal prostate biopsy (pPB) to be performed without general anesthesia. This paper presents the first results after establishing perineal MRI/ultrasound fusion biopsy (pFB) under local anesthesia without standard perioperative antibiotic prophylaxis. For this purpose, 144 patients were included in the study after pFB at the Vivantes Klinikum am Urban. No peri-interventional antibiotic prophylaxis was applied. Peri- and postoperatively, the pain sensation, measured using an analogue pain scale from 0-10, and complications were recorded. The median patient age was 68 and the median prostate-specific antigen (PSA) value 7.07 ng/ml. In all, 49% of the patients received primary PB. The overall detection rate for prostate cancer (PCa) was 71% and for PI-RADS 3, 4 and 5 was 44, 71 and 92%, respectively. The median pain sensation during biopsy was 2. Furthermore, 63% of patients with a transrectal prebiopsy considered this to be more painful and another 20% expressed similar pain levels. Only 1 patient developed a febrile urinary tract infection. The pFB of the prostate under local anesthesia without antibiotic, perioperative prophylaxis is a suitable alternative to the transrectal PB with regard to the detection rate of PCa, the side effect profile and the subjective pain perception of the patients during the intervention.


Assuntos
Anestesia Local , Neoplasias da Próstata , Antibioticoprofilaxia , Humanos , Biópsia Guiada por Imagem , Imageamento por Ressonância Magnética , Masculino , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/cirurgia
10.
Gut ; 57(2): 243-51, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17881540

RESUMO

BACKGROUND: Melanoma inhibitory activity 2 (MIA2) is a novel gene of the MIA gene family. The selective expression of MIA2 in hepatocytes is controlled by hepatocyte nuclear factor (HNF) 1 binding sites in the MIA2 promotor. In contrast, in most hepatocellular carcinomas (HCC) MIA2 expression is down-regulated or lost. AIM: In this study we examined the regulation and functional role of MIA2 in hepatocancerogenesis. METHODS AND RESULTS: In HCC cell lines and tissues HNF-1 expression was lower than in primary human hepatocytes (PHH) and corresponding non-tumorous tissue, respectively, and correlated significantly with the down-regulation of MIA2 expression. Re-expression of HNF-1 in HCC cells reinduced MIA2 in HCC cells to similar levels as found in PHH. Further, MIA2 was re-expressed in HCC cell lines by stable transfection, and the generated cell clones revealed a strongly reduced invasive potential and proliferation rate in vitro. In line with these findings treatment of HCC cells with recombinant MIA2 inhibited proliferation and invasion. In nude mice MIA2 re-expressing HCC cells grew significantly slower and revealed a less invasive growth pattern. Immunohistochemical analysis of a tissue microarray containing HCC and corresponding non-cancerous liver tissue of 85 patients confirmed reduced MIA2 expression in HCC. Furthermore, MIA2 negative HCC tissue showed a significantly higher Ki67 labelling index and loss of MIA2 expression correlated significantly with more advanced tumour stages. CONCLUSION: This study presents MIA2 as an inhibitor of HCC growth and invasion both in vitro and in vivo, and consequently, as a tumour suppressor of HCC. Further, our findings indicate a novel mechanism, how loss of HNF-1 expression in HCC affects tumorigenicity via down-regulation of MIA2.


Assuntos
Carcinoma Hepatocelular/genética , Proteínas da Matriz Extracelular/genética , Genes Supressores de Tumor , Neoplasias Hepáticas/genética , Proteínas de Neoplasias/genética , Proteínas Supressoras de Tumor/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígenos de Neoplasias , Ciclo Celular , Proliferação de Células , Células Cultivadas , Regulação para Baixo , Proteínas da Matriz Extracelular/antagonistas & inibidores , Feminino , Fator 1 Nuclear de Hepatócito/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas de Neoplasias/antagonistas & inibidores
11.
Transl Res ; 203: 57-72, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30213530

RESUMO

Genome editing represents a powerful tool to treat inherited disorders. Highly specific endonucleases induce a DNA double strand break near the mutant site, which is subsequently repaired by cellular DNA repair mechanisms that involve the presence of a wild type template DNA. In vivo applications of this strategy are still rare, in part due to the absence of appropriate animal models carrying human disease mutations and knowledge of the efficient targeting of endonucleases. Here we report the generation and characterization of a new mouse model for X-linked retinitis pigmentosa (XLRP) carrying a point mutation in the mutational hotspot exon ORF15 of the RPGR gene as well as a recognition site for the homing endonuclease I-SceI. Presence of the genomic modifications was verified at the RNA and protein levels. The mutant protein was observed at low levels. Optical coherence tomography studies revealed a slowly progressive retinal degeneration with photoreceptor loss starting at 9 months of age, paralleling the onset of functional deficits as seen in the electroretinogram. Early changes to the outer retinal bands can be used as biomarker during treatment applications. We further show for the first time efficient targeting using the I-SceI enzyme at the genomic locus in a proof of concept in photoreceptors following adeno-associated virus mediated gene transfer in vivo. Taken together, our studies not only provide a human-XLRP disease model but also act as a platform to design genome editing technology for retinal degenerative diseases using the currently available endonucleases.


Assuntos
Proteínas de Transporte/genética , Modelos Animais de Doenças , Proteínas do Olho/genética , Edição de Genes , Retinose Pigmentar/genética , Retinose Pigmentar/terapia , Animais , Humanos , Camundongos , Camundongos Knockout , Mutação , RNA Mensageiro , Reação em Cadeia da Polimerase Via Transcriptase Reversa
12.
Chem Commun (Camb) ; 53(51): 6836-6839, 2017 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-28597878

RESUMO

The incorporation properties of ceramide analogues for click chemistry in Jurkat T cells were investigated. The analogues varied in the acyl chain length and the position of the functional group for click chemistry. Fluorescence microscopy studies including anisotropy and quenching experiments showed significant differences in the accessibility of the functional group indicating different incorporation properties into the plasma membrane.


Assuntos
Membrana Celular/química , Ceramidas/química , Química Click , Humanos , Células Jurkat , Microscopia de Fluorescência , Estrutura Molecular , Imagem Óptica
13.
Rofo ; 178(2): 200-6, 2006 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-16435251

RESUMO

PURPOSE: To optimize contrast agent dose and pulse sequence parameters in order to achieve a maximal T1 enhancement in arthritic knee joints with ultra small superparamagnetic iron oxides (USPIO)-enhanced MRI. MATERIALS AND METHODS: Antigen-mediated arthritis was induced in the right knee of nine Sprague Dawley rats. The arthritic knee joint as well as the contralateral normal knee were investigated in a 2 Tesla MR scanner before as well as in short intervals up to 2 h after USPIO injection, using T1-weighted gradient echo (GE) sequences. Three rats each received intravenous injections of the new USPIO SHU 555 C (SH U 555 C, Schering AG, Berlin) at doses of 40, 100 and 200 micromol Fe/kg. Pulse sequence parameters of the GE-sequence were optimized by varying flip angles (alpha) and echo times (TE). Changes in signal intensities (SI) of the arthritic knee and contralateral normal knee were quantified as DeltaSI (%) = /([SIpost - SIpre] / SIpre) x 100 %/ and compared with histopathology. RESULTS: Histology of the arthritic knees demonstrated a marked inflammatory proliferation of the synovium. The USPIO SH U 555 C caused a significant increase in signal intensity of the arthritic joints on T1-weighted MR images (p < 0.05). This effect was optimized using a flip angle of 60-70 degrees, a minimal TE and a dose of 200 micromol Fe/kg. Visually the contralateral normal knee did not show any USPIO enhancement. CONCLUSION: Inflammation can be depicted with marked T1 enhancement by the USPIO SH U 555 C using high contrast agent doses and optimized MR pulse sequence parameters.


Assuntos
Artrite Experimental/diagnóstico , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Ferro , Imageamento por Ressonância Magnética/métodos , Óxidos , Animais , Meios de Contraste , Dextranos , Feminino , Óxido Ferroso-Férrico , Articulação do Joelho/patologia , Nanopartículas de Magnetita , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
14.
Cancer Res ; 55(24): 6002-5, 1995 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-8521381

RESUMO

The aim of the present study was to detect complex genetic alterations in colorectal carcinomas with and without microsatellite instability (MIN) by comparative genomic in situ hybridization. MIN due to replication errors is the hallmark of hereditary nonpolyposis colon cancer. None of 6 MIN-positive tumors showed amplifications, and only 2 tumors displayed deletions of one chromosomal segment each. In contrast, different gains and losses were observed in 11 of 12 MIN-negative carcinomas. The most frequent gains affected chromosomes 7, 13, and 20q, whereas deletions were observed on chromosomes 17, 18, and 9p. These results demonstrate different mechanisms of genetic instability in subgroups of colorectal carcinomas and may, therefore, support the hypothesis of different etiologies in tumors with and without MIN.


Assuntos
Aberrações Cromossômicas/genética , Neoplasias Colorretais/genética , DNA de Neoplasias/genética , Repetições de Microssatélites , Adulto , Idoso , Transtornos Cromossômicos , Replicação do DNA , Amplificação de Genes , Humanos , Hibridização In Situ , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Deleção de Sequência
15.
Phys Med Biol ; 61(17): N441-60, 2016 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-27499388

RESUMO

The hybrid technology cell-fluorescent ion track hybrid detector (Cell-Fit-HD) enables the investigation of radiation-related cellular events along single ion tracks on the subcellular scale in clinical ion beams. The Cell-Fit-HD comprises a fluorescent nuclear track detector (FNTD, the physical compartment), a device for individual particle detection and a substrate for viable cell-coating, i.e. the biological compartment. To date both compartments have been imaged sequentially in situ by confocal laser scanning microscopy (CLSM). This is yet in conflict with a functional read-out of the Cell-Fit-HD utilizing a fast live-cell imaging of the biological compartment with low phototoxicity on greater time scales. The read-out of the biological from the physical compartment was uncoupled. A read-out procedure was developed to image the cell layer by conventional widefield microscopy whereas the FNTD was imaged by CLSM. Point mapping registration of the confocal and widefield imaging data was performed. Non-fluorescent crystal defects (spinels) visible in both read-outs were used as control point pairs. The accuracy achieved was on the sub-µm scale. The read-out procedure by widefield microscopy does not impair the unique ability of spatial correlation by the Cell-Fit-HD. The uncoupling will enlarge the application potential of the hybrid technology significantly. The registration allows for an ultimate correlation of microscopic physical beam parameters and cell kinetics on greater time scales. The method reported herein will be instrumental for the introduction of a novel generation of compact detectors facilitating biodosimetric research towards high-throughput analysis.


Assuntos
Fenômenos Fisiológicos Celulares , Processamento de Imagem Assistida por Computador/métodos , Microscopia Confocal/métodos , Radiometria/instrumentação , Radiometria/métodos , Células A549 , Óxido de Alumínio/química , Sobrevivência Celular , Fluorescência , Humanos , Transferência Linear de Energia , Microscopia Confocal/instrumentação
16.
Biochim Biophys Acta ; 981(2): 213-25, 1989 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-2543459

RESUMO

A membrane fraction of intermediate density between inner and outer membrane was isolated by density gradient centrifugation from osmotically disrupted mitochondria of rat liver, brain, and kidney. The fraction was hexokinase rich and could therefore be further purified using specific antibodies against hexokinase and immunogold labelling techniques. In agreement with recent findings the gradient fraction which cosedimented with hexokinase contained the boundary membrane contact sites because it was composed of outer and inner membrane components and beside hexokinase, was enriched also by activity of creatine kinase and nucleoside diphosphate kinase. In contrast the activity of adenylate kinase appeared to be concentrated beyond the contact sites in the outer membrane fraction. By employing surface proteolysis analysis and specific blockers of the outer membrane pore we observed that the location of the kinases relative to the membrane components in the contact fraction resembled that of intact mitochondria. This specific organization of some peripheral kinases in the contact sites suggested an important role of the voltage dependence of the outer membrane pore, in that the pore may become limiting in anion exchange because of influence of the inner membrane potential on the closely attached outer membrane. Such control of anion exchange would lead to a dynamic compartmentation at the mitochondrial surface by the formation of contact sites, which may explain the preferential utilization of cytosolic creatine by the mitochondrial creatine kinase, as postulated in the phosphocreatine shuttle.


Assuntos
Adenilato Quinase/metabolismo , Creatina Quinase/metabolismo , Mitocôndrias/ultraestrutura , Núcleosídeo-Difosfato Quinase/metabolismo , Fosfotransferases/metabolismo , Animais , Transporte Biológico/efeitos dos fármacos , Encéfalo/ultraestrutura , Fracionamento Celular , Centrifugação com Gradiente de Concentração , Hexoquinase/imunologia , Hexoquinase/metabolismo , Técnicas Imunológicas , Membranas Intracelulares/enzimologia , Rim/ultraestrutura , Mitocôndrias/enzimologia , Mitocôndrias Hepáticas/enzimologia , Mitocôndrias Hepáticas/ultraestrutura , Peso Molecular , Fragmentos de Peptídeos/análise , Peptídeo Hidrolases/farmacologia , Ratos
17.
Cell Death Differ ; 2(2): 141-50, 1995 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17180076

RESUMO

Plasma membrane and nucleus can be primary targets of tumour cell killing by activated macrophages (AMø). Necrotic-type cytotoxicity with loss of membrane integrity and cytoplasmic swelling was expressed by AMø from normal and from perforin-deficient mice, indicating that perforin was not involved. Incubation with AMø consistently triggered the release of thymidine from prelabelled targets, whereas chromatin condensation and small DNA fragments were only occasionally detected. It is shown by means of Pulsed-Field Gel Electrophoresis that DNA degradation in target cells is a slowly progressing process that may stop at any time, indicating that nuclear-type killing doesnot necessarily lead to the formation of low molecular weight fragments. Neither Fas nor the p55 tumour necrosis factor receptor appear to be involved in signalling nuclear-type killing. Accordingly, AMø do mediate membrane- and nuclear-type killing but the mechanisms differ from those identified in T cell cytotoxicity.

18.
Arch Intern Med ; 139(12): 1355-60, 1979 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-518219

RESUMO

Casts with numerous and unusually large granules were seen in the urine of a child with renal Fanconi's syndrome. When the urine sediment was sealed under a coverslip for several days, many granules changed to filamentous bacterial variants that segmented and, finally, appeared as streptococcal-like forms. When the patient's blood was cultured by a special method, bacterial variants grew consistently, and frequently reverted to parent coccal forms, although conventional cultures were negative. Variants from blood cultures had the same morphology and staining properties as granules in casts and in cystic structures found within hypertrophied renal pelvic epithelial cells. Cryptic parasitization with bacterial variants probably occurs in many nephropathies. Variants are known to produce toxins and immunogens, which could lead to mesangial and basement membrane deposits as well as to occlusive reactions in the renal microcirculation.


Assuntos
Formas Bacterianas Atípicas/isolamento & purificação , Bacteriúria/microbiologia , Síndrome de Fanconi/microbiologia , Rim/microbiologia , Formas Bacterianas Atípicas/ultraestrutura , Bacteriúria/patologia , Pré-Escolar , Epitélio/microbiologia , Síndrome de Fanconi/patologia , Feminino , Humanos , Rim/patologia , Fígado/patologia , Doenças Renais Policísticas/patologia
19.
Hum Gene Ther ; 9(14): 2075-82, 1998 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-9759934

RESUMO

Mutations of the tumor suppressor gene p53 are the most common genetic alterations observed in human cancer. Loss of wild-type p53 function impairs cell cycle arrest as well as repair mechanisms involved in response to DNA damage. Further, apoptotic pathways as induced by radio- or chemotherapy are also abrogated. Gene transfer of wild-type p53 was shown to reverse these deficiencies and to induce apoptosis in vitro and in preclinical in vivo tumor models. A phase I dose escalation study of a single intratumoral injection of a replication-defective adenoviral expression vector encoding wild-type p53 was carried out in patients with incurable non-small cell lung cancer. All patients enrolled had p53 protein overexpression as a marker of mutant p53 status in pretreatment tumor biopsies. Treatment was performed either by bronchoscopic intratumoral injection or by CT-guided percutaneous intratumoral injection of the vector solution. Fifteen patients were enrolled in two centers, and were treated at four different dose levels ranging from 10(7) to 10(10) PFU (7.5 x 10(9) to 7.5 x 10(12) particles). No clinically significant toxicity was observed. Successful transfer of wild-type p53 was achieved only with higher vector doses. Vector-specific wild-type p53 RNA sequences could be demonstrated in posttreatment biopsies of six patients. Transient local disease control by a single intratumoral injection of the vector solution was observed in four of those six successfully transduced patients. There was no evidence of clinical responses at untreated tumor sites. Wild-type p53 gene therapy by intratumoral injection of a replication-defective adenoviral expression vector is safe, feasible, and biologically effective in patients with advanced non-small cell lung cancer.


Assuntos
Adenoviridae/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Genes p53/genética , Terapia Genética/estatística & dados numéricos , Neoplasias Pulmonares/genética , Adolescente , Adulto , Idoso , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Técnicas de Transferência de Genes/efeitos adversos , Terapia Genética/efeitos adversos , Vetores Genéticos/genética , Humanos , Injeções/métodos , Masculino , Pessoa de Meia-Idade , Mortalidade , RNA Mensageiro/genética , Resultado do Tratamento
20.
J Invest Dermatol ; 106(1): 194-7, 1996 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8592074

RESUMO

Initiation and progression of melanocytic and non-melanocytic skin tumors are accompanied and probably caused by a variety of genetic defects. In contrast to other human tumors, however, limited amounts of available tissue in skin cancer often hamper extensive genetic studies of native material of early lesions. Therefore, we applied a novel DNA fingerprinting technique based on polymerase chain reaction (PCR), the arbitrarily primed PCR (AP-PCR). This technique enabled us to scan large parts of the genome (about 30 kb/PCR reaction) for somatic mutations starting with minute amounts of tissue. In contrast to previous reports on AP-PCR, we were able to visualize PCR products by a rapid nonradioactive silver-staining technique using a simple device for staining of large polyacrylamide gels. In nine benign and malignant melanocytic skin tumors, the method provided a set of reproducible DNA fingerprints. Genetic defects were detected by comparing the fingerprints of tumor cells and constitutive DNA from blood leukocytes. Since nonradioactive AP-PCR fingerprinting also offers the unique capability to isolate and sequence polymorphic DNA fragments from fingerprint gels, we conclude that this technique seems to be important and practically feasible for elucidating the genetic roots of skin tumors.


Assuntos
Melanoma/genética , Nevo de Células Epitelioides e Fusiformes/genética , Nevo Pigmentado/genética , Reação em Cadeia da Polimerase/métodos , Neoplasias Cutâneas/genética , Sequência de Bases , Impressões Digitais de DNA , Desenho de Equipamento , Humanos , Dados de Sequência Molecular , Mutação , Reação em Cadeia da Polimerase/instrumentação , Prata , Coloração e Rotulagem
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