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1.
Radiat Res ; 201(5): 504-513, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38471521

RESUMO

Increased radiological and nuclear threats require preparedness. Our earlier work identified a set of four genes (DDB2, FDXR, POU2AF1 and WNT3), which predicts severity of the hematological acute radiation syndrome (H-ARS) within the first three days postirradiation In this study of 41 Rhesus macaques (Macaca mulatta, 27 males, 14 females) irradiated with 5.8-7.2 Gy (LD29-50/60), including some treated with gamma-tocotrienol (GT3, a radiation countermeasure) we independently validated these genes as predictors in both sexes and examined them after three days. At the Armed Forces Radiobiology Research Institute/Uniformed Services University of the Health Sciences, peripheral whole blood (1 ml) of Rhesus macaques was collected into PAXgene® Blood RNA tubes pre-irradiation after 1, 2, 3, 35 and 60 days postirradiation, stored at -80°C for internal experimental analyses. Leftover tubes from these already ongoing studies were kindly provided to Bundeswehr Institute of Radiobiology. RNA was isolated (QIAsymphony), converted into cDNA, and for further gene expression (GE) studies quantitative RT-PCR was performed. Differential gene expression (DGE) was measured relative to the pre-irradiation Rhesus macaques samples. Within the first three days postirradiation, we found similar results to human data: 1. FDXR and DDB2 were up-regulated, FDXR up to 3.5-fold, and DDB2 up to 13.5-fold in the median; 2. POU2AF1 appeared down regulated around tenfold in nearly all Rhesus macaques; 3. Contrary to human data, DDB2 was more up-regulated than FDXR, and the difference of the fold change (FC) ranged between 2.4 and 10, while the median fold changes of WNT3, except days 1 and 35, were close to 1. Nevertheless, 46% of the Rhesus macaques showed down-regulated WNT3 on day one postirradiation, which decreased to 12.2% on day 3 postirradiation. Considering the extended phase, there was a trend towards decreased fold changes at day 35, with median-fold changes ranging from 0.7 for DDB2 to 0.1 for POU2AF1, and on day 60 postirradiation, DGE in surviving animals was close to pre-exposure values for all four genes. In conclusion, the diagnostic significance for radiation-induced H-ARS severity prediction of FDXR, DDB2, and POU2AF1 was confirmed in this Rhesus macaques model. However, DDB2 showed higher GE values than FDXR. As shown in previous studies, the diagnostic significance of WNT3 could not be reproduced in Rhesus macaques; this could be due to the choice of animal model and methodological challenges.


Assuntos
Síndrome Aguda da Radiação , Macaca mulatta , Animais , Masculino , Feminino , Síndrome Aguda da Radiação/sangue , Síndrome Aguda da Radiação/genética
2.
Radiat Res ; 201(5): 487-498, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38471523

RESUMO

In gene expression (GE) studies, housekeeping genes (HKGs) are required for normalization purposes. In large-scale inter-laboratory comparison studies, significant differences in dose estimates are reported and divergent HKGs are employed by the teams. Among them, the 18S rRNA HKG is known for its robustness. However, the high abundance of 18S rRNA copy numbers requires dilution, which is time-consuming and a possible source of errors. This study was conducted to identify the most promising HKGs showing the least radiation-induced GE variance after radiation exposure. In the screening stage of this study, 35 HKGs were analyzed. This included selected HKGs (ITFG1, MRPS5, and DPM1) used in large-scale biodosimetry studies which were not covered on an additionally employed pre-designed 96-well platform comprising another 32 HKGs used for different exposures. Altogether 41 samples were examined, including 27 ex vivo X-ray irradiated blood samples (0, 0.5, 4 Gy), six X-irradiated samples (0, 0.5, 5 Gy) from two cell lines (U118, A549), as well as eight non-irradiated tissue samples to encompass multiple biological entities. In the independent validation stage, the most suitable candidate genes were examined from another 257 blood samples, taking advantage of already stored material originating from three studies. These comprise 100 blood samples from ex vivo X-ray irradiated (0-4 Gy) healthy donors, 68 blood samples from 5.8 Gy irradiated (cobalt-60) Rhesus macaques (RM) (LD29/60) collected 0-60 days postirradiation, and 89 blood samples from chemotherapy-(CTx) treated breast tumor patients. CTx and radiation-induced GE changes in previous studies appeared comparable. RNA was isolated, converted into cDNA, and GE was quantified employing TaqMan assays and quantitative RT-PCR. We calculated the standard deviation (SD) and the interquartile range (IQR) as measures of GE variance using raw cycle threshold (Ct) values and ranked the HKGs accordingly. Dose, time, age, and sex-dependent GE changes were examined employing the parametrical t-test and non-parametrical Kruskal Wallis test, as well as linear regression analysis. Generally, similar ranking results evolved using either SD or IQR GE measures of variance, indicating a tight distribution of GE values. PUM1 and PGK1 showed the lowest variance among the first ten most suitable genes in the screening phase. MRPL19 revealed low variance among the first ten most suitable genes in the screening phase only for blood and cells, but certain comparisons indicated a weak association of MRPL19 with dose (P = 0.02-0.09). In the validation phase, these results could be confirmed. Here, IQR Ct values from, e.g., X-irradiated blood samples were 0.6 raw Ct values for PUM1 and PGK1, which is considered to represent GE differences as expected due to methodological variance. Overall, when compared, the GE variance of both genes was either comparable or lower compared to 18S rRNA. Compared with the IQR GE values of PUM1 and PGKI, twofold-fivefold increased values were calculated for the biodosimetry HKG HPRT1, and comparable values were calculated for biodosimetry HKGs ITFG1, MRPS5, and DPM1. Significant dose-dependent associations were found for ITFG1 and MRPS5 (P = 0.001-0.07) and widely absent or weak (P = 0.02-0.07) for HPRT1 and DPM1. In summary, PUM1 and PGK1 appeared most promising for radiation exposure studies among the 35 HKGs examined, considering GE variance and adverse associations of GE with dose.


Assuntos
Genes Essenciais , RNA Ribossômico 18S , Exposição à Radiação , Radiometria , RNA Ribossômico 18S/genética , Humanos , Exposição à Radiação/efeitos adversos , Masculino , Proteínas de Ligação a RNA/genética , Feminino , Adulto , Relação Dose-Resposta à Radiação , Pessoa de Meia-Idade , Animais
3.
Radiat Res ; 201(5): 384-395, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38282135

RESUMO

Radiosensitivity differs in humans and possibly in closely related nonhuman primates. The reasons for variation in radiosensitivity are not well known. In an earlier study, we examined gene expression (GE) pre-radiation in peripheral blood among male (n = 62) and female (n = 60) rhesus macaques (n = 122), which did or did not survive (up to 60 days) after whole-body exposure of 7.0 Gy (LD66/60). Eight genes (CHD5, CHI3L1, DYSF, EPX, IGF2BP1, LCN2, MBOAT4, SLC22A4) revealed significant associations with survival. Access to a second rhesus macaque cohort (males = 40, females = 23, total n = 63) irradiated with 5.8-7.2 Gy (LD29-50/60) and some treated with gamma-tocotrienol (GT3, a radiation countermeasure) allowed us to validate these gene expression changes independently. Total RNA was isolated from whole blood samples and examined by quantitative RT-PCR on a 96-well format. cycle threshold (Ct)-values normalized to 18S rRNA were analyzed for their association with survival. Regardless of the species-specific TaqMan assay, similar results were obtained. Two genes (CHD5 and CHI3L1) out of eight revealed a significant association with survival in the second cohort, while only CHD5 (involved in DNA damage response and proliferation control) showed mean gene expression changes in the same direction for both cohorts. No expected association of CHD5 GE with dose, treatment, or sex could be established. Instead, we observed significant associations for those comparisons comprising pre-exposure samples with CHD5 Ct values ≤ 11 (total n = 17). CHD5 Ct values ≤ 11 in these comparisons were mainly associated with increased frequencies (61-100%) of non-survivors, a trend which depending on the sample numbers, reached significance (P = 0.03) in males and, accordingly, in females. This was also reflected by a logistic regression model including all available samples from both cohorts comprising CHD5 measurements (n = 104, odds ratio 1.38, 95% CI 1.07-1.79, P = 0.01). However, this association was driven by males (odds ratio 1.62, 95% CI 1.10-2.38, P = 0.01) and CHD5 Ct values ≤ 11 since removing low CHD5 Ct values from this model, converted to insignificance (P = 0.19). A second male subcohort comprising high CHD5 Ct values ≥ 14.4 in both cohorts (n = 5) appeared associated with survival. Removing these high CHD5 Ct values converted the model borderline significant (P = 0.051). Based on the probability function of the receiver operating characteristics (ROC) curves, 8 (12.3%) and 5 (7.7%) from 65 pre-exposure RNA measurements in males, death and survival could be predicted with a negative and positive predictive value ranging between 85-100%. An associated odds ratio reflected a 62% elevated risk for dying or surviving per unit change (Ct-value) in gene expression, considering the before-mentioned CHD5 thresholds in RNA copy numbers. In conclusion, we identified two subsets of male animals characterized by increased (Ct values ≤ 11) and decreased (Ct values ≥ 14.4) CHD5 GE copy numbers before radiation exposure, which independently of the cohort, radiation exposure or treatment appeared to predict the death or survival in males.


Assuntos
Macaca mulatta , Tolerância a Radiação , Animais , Masculino , Feminino , Tolerância a Radiação/genética , Estudos de Coortes , Regulação da Expressão Gênica/efeitos da radiação , Relação Dose-Resposta à Radiação , Irradiação Corporal Total
4.
Radiat Res ; 199(6): 598-615, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-37057982

RESUMO

Early and high-throughput individual dose estimates are essential following large-scale radiation exposure events. In the context of the Running the European Network for Biodosimetry and Physical Dosimetry (RENEB) 2021 exercise, gene expression assays were conducted and their corresponding performance for dose-assessment is presented in this publication. Three blinded, coded whole blood samples from healthy donors were exposed to 0, 1.2 and 3.5 Gy X-ray doses (240 kVp, 1 Gy/min) using the X-ray source Yxlon. These exposures correspond to clinically relevant groups of unexposed, low dose (no severe acute health effects expected) and high dose exposed individuals (requiring early intensive medical health care). Samples were sent to eight teams for dose estimation and identification of clinically relevant groups. For quantitative reverse transcription polymerase chain reaction (qRT-PCR) and microarray analyses, samples were lysed, stored at 20°C and shipped on wet ice. RNA isolations and assays were run in each laboratory according to locally established protocols. The time-to-result for both rough early and more precise later reports has been documented where possible. Accuracy of dose estimates was calculated as the difference between estimated and reference doses for all doses (summed absolute difference, SAD) and by determining the number of correctly reported dose estimates that were defined as ±0.5 Gy for reference doses <2.5 Gy and ±1.0 Gy for reference doses >3 Gy, as recommended for triage dosimetry. We also examined the allocation of dose estimates to clinically/diagnostically relevant exposure groups. Altogether, 105 dose estimates were reported by the eight teams, and the earliest report times on dose categories and estimates were 5 h and 9 h, respectively. The coefficient of variation for 85% of all 436 qRT-PCR measurements did not exceed 10%. One team reported dose estimates that systematically deviated several-fold from reported dose estimates, and these outliers were excluded from further analysis. Teams employing a combination of several genes generated about two-times lower median SADs (0.8 Gy) compared to dose estimates based on single genes only (1.7 Gy). When considering the uncertainty intervals for triage dosimetry, dose estimates of all teams together were correctly reported in 100% of the 0 Gy, 50% of the 1.2 Gy and 50% of the 3.5 Gy exposed samples. The order of dose estimates (from lowest to highest) corresponding to three dose categories (unexposed, low dose and highest exposure) were correctly reported by all teams and all chosen genes or gene combinations. Furthermore, if teams reported no exposure or an exposure >3.5 Gy, it was always correctly allocated to the unexposed and the highly exposed group, while low exposed (1.2 Gy) samples sometimes could not be discriminated from highly (3.5 Gy) exposed samples. All teams used FDXR and 78.1% of correct dose estimates used FDXR as one of the predictors. Still, the accuracy of reported dose estimates based on FDXR differed considerably among teams with one team's SAD (0.5 Gy) being comparable to the dose accuracy employing a combination of genes. Using the workflow of this reference team, we performed additional experiments after the exercise on residual RNA and cDNA sent by six teams to the reference team. All samples were processed similarly with the intention to improve the accuracy of dose estimates when employing the same workflow. Re-evaluated dose estimates improved for half of the samples and worsened for the others. In conclusion, this inter-laboratory comparison exercise enabled (1) identification of technical problems and corrections in preparations for future events, (2) confirmed the early and high-throughput capabilities of gene expression, (3) emphasized different biodosimetry approaches using either only FDXR or a gene combination, (4) indicated some improvements in dose estimation with FDXR when employing a similar methodology, which requires further research for the final conclusion and (5) underlined the applicability of gene expression for identification of unexposed and highly exposed samples, supporting medical management in radiological or nuclear scenarios.


Assuntos
Exposição à Radiação , Radiometria , Humanos , Relação Dose-Resposta à Radiação , Radiometria/métodos , Exposição à Radiação/efeitos adversos , Exposição à Radiação/análise , Bioensaio/métodos , Expressão Gênica
5.
Radiat Res ; 199(1): 17-24, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36445953

RESUMO

Radiation-induced gene expression (GE) changes can be used for early and high-throughput biodosimetry within the first three days postirradiation. However, is the method applicable in situations such as the Alexander Litvinenko case or the Goiania accident, where diagnosis occurred in a prefinal health stage? We aimed to characterize gene expression changes in a prefinal health stage of lethally irradiated male and female rhesus macaques. Peripheral blood was drawn pre-exposure and at the prefinal stage of male and female animals, which did not survive whole-body exposure with 700 cGy (LD66/60). RNA samples originated from a blinded randomized Good Laboratory Practice study comprising altogether 142 irradiated rhesus macaques of whom 60 animals and blood samples (15 samples for both time points and sexes) were used for this analysis. We evaluated GE on 34 genes widely used in biodosimetry and prediction of the hematological acute radiation syndrome severity (H-ARS) employing quantitative real-time polymerase chain reaction (qRT-PCR). These genes were run in duplicate and triplicate and altogether 96 measurements per time point and sex could be performed. In addition, 18S ribosomal RNA (rRNA) was measured to depict the ribosome/transcriptome status as well as for normalization purposes and 16S rRNA was evaluated as a surrogate for bacteremia. Mean differential gene expression (DGE) was calculated for each gene and sex including all replicate measurements and using pre-exposure samples as the reference. From 34 genes, altogether 27 genes appeared expressed. Pre-exposure samples revealed no signs of bacteremia and 18S rRNA GE was in the normal range in all 30 samples. Regarding prefinal samples, 46.7% and 40% of animals appeared infected in females and males, respectively, and for almost all males this was associated with out of normal range 18S rRNA values. The total number of detectable GE measurements was sixfold (females) and 15-fold (males) reduced in prefinal relative to pre-exposure samples and about tenfold lower in 80% of prefinal compared to pre-exposure samples (P < 0.0001). An overall 11-fold (median) downregulation in prefinal compared to pre-exposure samples was identified for most of the 27 genes and even FDXR appeared 4-14-fold downregulated in contrast to a pronounced up-regulation according to cited work. This pattern of overall downregulation of almost all genes and the rapid reduction of detectable genes at a prefinal stage was found in uninfected animals with normal range 18S rRNA as well. In conclusion, in a prefinal stage after lethal radiation exposure, the ribosome/transcriptome status remains present (based on normal range 18S rRNA values) in 60-67% of animals, but the whole transcriptome activity in general appears silenced and cannot be used for biodosimetry purposes, but probably as an indicator for an emerging prefinal health stage.


Assuntos
Bacteriemia , Transcriptoma , Animais , Masculino , Feminino , Macaca mulatta , RNA Ribossômico 18S , RNA Ribossômico 16S , Perfilação da Expressão Gênica
6.
Sci Rep ; 11(1): 9756, 2021 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-33963206

RESUMO

Large-scale radiation emergency scenarios involving protracted low dose rate radiation exposure (e.g. a hidden radioactive source in a train) necessitate the development of high throughput methods for providing rapid individual dose estimates. During the RENEB (Running the European Network of Biodosimetry) 2019 exercise, four EDTA-blood samples were exposed to an Iridium-192 source (1.36 TBq, Tech-Ops 880 Sentinal) at varying distances and geometries. This resulted in protracted doses ranging between 0.2 and 2.4 Gy using dose rates of 1.5-40 mGy/min and exposure times of 1 or 2.5 h. Blood samples were exposed in thermo bottles that maintained temperatures between 39 and 27.7 °C. After exposure, EDTA-blood samples were transferred into PAXGene tubes to preserve RNA. RNA was isolated in one laboratory and aliquots of four blinded RNA were sent to another five teams for dose estimation based on gene expression changes. Using an X-ray machine, samples for two calibration curves (first: constant dose rate of 8.3 mGy/min and 0.5-8 h varying exposure times; second: varying dose rates of 0.5-8.3 mGy/min and 4 h exposure time) were generated for distribution. Assays were run in each laboratory according to locally established protocols using either a microarray platform (one team) or quantitative real-time PCR (qRT-PCR, five teams). The qRT-PCR measurements were highly reproducible with coefficient of variation below 15% in ≥ 75% of measurements resulting in reported dose estimates ranging between 0 and 0.5 Gy in all samples and in all laboratories. Up to twofold reductions in RNA copy numbers per degree Celsius relative to 37 °C were observed. However, when irradiating independent samples equivalent to the blinded samples but increasing the combined exposure and incubation time to 4 h at 37 °C, expected gene expression changes corresponding to the absorbed doses were observed. Clearly, time and an optimal temperature of 37 °C must be allowed for the biological response to manifest as gene expression changes prior to running the gene expression assay. In conclusion, dose reconstructions based on gene expression measurements are highly reproducible across different techniques, protocols and laboratories. Even a radiation dose of 0.25 Gy protracted over 4 h (1 mGy/min) can be identified. These results demonstrate the importance of the incubation conditions and time span between radiation exposure and measurements of gene expression changes when using this method in a field exercise or real emergency situation.


Assuntos
Células Sanguíneas/metabolismo , Raios gama/efeitos adversos , Regulação da Expressão Gênica/efeitos da radiação , Laboratórios , Doses de Radiação , Exposição à Radiação , Raios X/efeitos adversos , Relação Dose-Resposta à Radiação , Humanos , Reprodutibilidade dos Testes
8.
Chirurg ; 92(5): 434-439, 2021 May.
Artigo em Alemão | MEDLINE | ID: mdl-33566118

RESUMO

Smart technologies facilitate our daily life in many respects, e.g. by rendering travel safer. In medicine, however, they have so far hardly been used, even though the demographic changes with an aging population in small or single households warrant an urgent change of our traditional care structures. Furthermore, patients are more demanding and better informed than they were a few decades ago. Enhanced recovery after surgery (ERAS) focusses on good prehabilitation as well as fast rehabilitation and therefore represents, even almost 20 years after the first publication, a modern and evidence-based treatment concept. Nevertheless, it is still not comprehensively implemented nationwide. The reasons for this may be concerns regarding an early discharge. In addition, there is often a gap in care care between discharge from hospital and start of the follow-up rehabilitation. In order to improve acceptance of the ERAS concept, to fulfil the patients' needs for better information while decreasing the workload of the medical staff and to close the gap in care after discharge from hospital, integrating ERAS into the concept of a smart hospital with subsequent transition into a temporary smart home is an appealing idea. With the use of an individually configurated online learning platform, a large part of the information flow can be transferred from the outpatient clinic to the pre-outpatient area (i.e. the patient's home). Consequently, patients will be better prepared for their first contact with the hospital. After a short stay in hospital the patient is then discharged into the serviced apartments of the smart quarter, where a stress-free recovery in a home-like environment is possible. The further rehabilitation is undertaken there under virtual guidance, following individualized schedules on demand.


Assuntos
Recuperação Pós-Cirúrgica Melhorada , Idoso , Humanos , Tempo de Internação
9.
Radiat Res ; 195(1): 25-37, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33181854

RESUMO

Radiosensitivity differs in humans and likely among closely-related primates. Reasons for variation in radiosensitivity are not well known. We examined preirradiation gene expression in peripheral blood among male and female rhesus macaques which did or did not survive (up to 60 days) after whole-body irradiation with 700 cGy (LD66/60). RNA samples originated from a blinded randomized Good Laboratory Practice study in 142 irradiated rhesus macaques. Animals were untreated (placebo), or treated using recombinant human IL-12, G-CSF or combination of the two. We evaluated gene expression in a two-phase study design where phase I was a whole genome screen [next generation sequencing (NGS)] for mRNAs (RNA-seq) using five RNA samples from untreated male and female animals per group of survivor and non-survivor (total n = 20). Differential gene expression (DGE) was defined as a statistically significant and ≥2-fold up- or downregulation of mRNA species and was calculated between groups of survivors and non-survivors (reference) and by gender. Altogether 659 genes were identified, but the overlapping number of differentially expressed genes (DGE) observed in both genders was small (n = 36). Fifty-eight candidate mRNAs were chosen for independent validation in phase II using the remaining samples (n = 122) evaluated with qRT-PCR. Among the 58 candidates, 16 were of significance or borderline significance (t test) by DGE. Univariate and multivariate logistic regression analysis and receiver operating characteristic (ROC) curve analysis further refined and identified the most outstanding validated genes and gene combinations. For untreated male macaques, we identified EPX (P = 0.005, ROC=1.0), IGF2BP1 (P = 0.05, ROC=0.74) and the combination of EPX with SLC22A4 (P = 0.03, ROC=0.85) which appeared most predictive for the clinical outcome for treated and combined (untreated and treated) male macaque groups, respectively. For untreated, treated and both combined female macaque groups the same gene (MBOAT4, P = 0.0004, ROC = 0.81) was most predictive. Based on the probability function of the ROC curves, up to 74% of preirradiation RNA measurements predicted survival with a positive and negative predictive value ranging between 85-100% and associated odds ratios reflecting a 2-3-fold elevated risk for surviving per unit change (cycle threshold value) in gene expression. In conclusion, we identified gender-dependent genes and gene combinations in preirradiation blood samples for survival prediction after irradiation in rhesus macaques.


Assuntos
Expressão Gênica/genética , RNA Mensageiro/genética , Tolerância a Radiação/genética , Irradiação Corporal Total/efeitos adversos , Animais , Feminino , Expressão Gênica/efeitos dos fármacos , Expressão Gênica/efeitos da radiação , Perfilação da Expressão Gênica , Fator Estimulador de Colônias de Granulócitos/genética , Fator Estimulador de Colônias de Granulócitos/farmacologia , Humanos , Interleucina-12/genética , Interleucina-12/farmacologia , Masculino , Tolerância a Radiação/efeitos dos fármacos , Proteínas Recombinantes/genética , Proteínas Recombinantes/farmacologia
10.
Radiat Res ; 194(5): 476-484, 2020 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-32991726

RESUMO

To better predict clinical outcome after radiation exposure, it is very important to know the absorbed dose and body areas exposed. Previously we found that 22 miRNAs appeared to predict total- and partial-body irradiation (TBI and PBI, respectively) patterns and were suggestive of the percentage of the body exposed in a baboon model. Motivated by these results, we performed a similar analysis on the transcriptional level (mRNAs) using whole genome microarrays. From 17 irradiated baboons, blood samples were taken before, and at 1, 2, 7, 28 and 75-106 days postirradiation to an equivalent TBI dose of 2.5 or 5 Gy applied either to the total body or to different parts of the body such as the upper body (UBE) or left hemibody (LHB). We compared quantile normalized log2-transformed gene expression values with three exposure pattern comparisons, namely TBI vs. PBI, TBI vs. LHB and UBE vs. LHB using Kruskal-Wallis and logistic regression analysis for receiver-operator characteristic (ROC) calculation. We found several hundred significantly (P < 0.05) and ≥2-fold deregulated mRNAs per exposure pattern comparison with a peak of 163-860 mRNAs at day 28. Lower numbers on day 2 (60 mRNAs) and day 7 (91-162 mRNAs) were observed, with the lowest number of deregulated mRNAs at day 75-106 (22-58 mRNAs). The 14 most promising mRNAs (e.g., LTF, DEFA3, OLFM4) appeared 10.1-46.2-fold upregulated and the exposure groups were completely or almost completely discriminated (ROC between 0.8-1.0). Several of the mRNA gene expression changes were significantly associated with the percentage of the body exposed. The numbers of overlapping genes used for diagnosis on consecutive days postirradiation were mostly 0 or less than 10. Bioinformatic analysis confirmed that at each time point different biological processes predominated. Our results suggest mRNA changes over time may be used to retrospectively determine radiation exposure patterns as partial or total body. mRNA gene expression changes likely could be applied over a longer time frame (2-75 days postirradiation) than miRNA, but due to the transient gene expression changes a different set of candidate mRNAs appears to be required at each day after irradiation.


Assuntos
Raios gama/efeitos adversos , RNA Mensageiro/biossíntese , RNA Neoplásico/biossíntese , Exposição à Radiação , Irradiação Corporal Total/efeitos adversos , Absorção de Radiação , Animais , Radioisótopos de Cobalto , Relação Dose-Resposta à Radiação , Perfilação da Expressão Gênica , Masculino , Proteínas de Neoplasias/biossíntese , Proteínas de Neoplasias/genética , Análise de Sequência com Séries de Oligonucleotídeos , Especificidade de Órgãos , Papio , Estudo de Prova de Conceito , RNA Mensageiro/sangue , RNA Neoplásico/sangue
11.
Chirurg ; 91(6): 461-465, 2020 Jun.
Artigo em Alemão | MEDLINE | ID: mdl-32185427

RESUMO

Intraoperative imaging diagnostics during open vascular surgical procedures aim to enhance diagnostic certainty during the operation, ensure quality control documentation and reduce avoidable complications; however, the evidence for the various diagnostic imaging procedures with respect to improvement of perioperative outcome is not confirmed for carotid endarterectomy or for infrainguinal bypass surgery. Nevertheless, an intraoperative diagnostic control is principally recommended. The advantage of intraoperative imaging is confirmed and essential for the surgical reconstruction of bypass occlusions and acute thromboembolic occlusions.


Assuntos
Endarterectomia das Carótidas , Procedimentos Cirúrgicos Vasculares
12.
Chirurg ; 89(9): 663-668, 2018 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-29589077

RESUMO

Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) may significantly improve overall survival in selected patients with peritoneal metastases of colorectal cancer. For good oncological results complete macroscopic cytoreduction is crucial; furthermore, a linear correlation between peritoneal tumor load, as determined by the peritoneal cancer index (PCI) and overall survival has been demonstrated; therefore, surgical treatment should be initiated as early as possible. Synchronous resection of up to three liver metastases may be performed safely and with good results and no influence on the morbidity. With respect to intraperitoneal chemotherapy, mitomycin C and oxaliplatin are most commonly used and may be regarded as equal; however, for perioperative chemotherapy study results are so far inconclusive with some trials hinting at decreased overall survival following neoadjuvant chemotherapy. Adjuvant therapy is likely to improve overall survival if at least 6 cycles are applied. Early detection of peritoneal metastases is difficult at present but might be facilitated in the future by the use of liquid biopsies, which may detect circulating free tumor-specific DNA or RNA. In the meantime, planned second-look laparotomy should be considered for patients at high risk of peritoneal recurrence. In addition, several international studies are currently evaluating the concept of adjuvant or prophylactic HIPEC. The CRS and HIPEC may be repeated in cases of recurrence and should be considered in suitable patients, applying the same criteria as for primary CRS and HIPEC. A recurrence-free interval of >2 years is associated with a significantly better prognosis.


Assuntos
Neoplasias Colorretais , Neoplasias Peritoneais , Protocolos de Quimioterapia Combinada Antineoplásica , Quimioterapia Adjuvante , Quimioterapia do Câncer por Perfusão Regional , Neoplasias Colorretais/patologia , Terapia Combinada , Procedimentos Cirúrgicos de Citorredução , Humanos , Hipertermia Induzida , Recidiva Local de Neoplasia , Neoplasias Peritoneais/secundário , Neoplasias Peritoneais/cirurgia
13.
J Cancer Res Clin Oncol ; 142(12): 2593-2601, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27630023

RESUMO

AIM: In the 7th edition of the TNM classification, not only HCC with distant metastases but also those with regional lymph node metastases are classified as stage IV. MATERIALS AND METHODS, RESULTS: From our prospectively recorded tumor registry, 138 patients (17 %) with HCC were in stage IV. Among those were 68 and 70, respectively, in stage IVA (regional lymph node metastases) and IVB (distant metastases). The tumors were less frequently treated with resection or local ablative treatment (chemoembolization, RFA, SIRT, percutaneous radiation) than patients in stage I-III. Ten HCCs were resected. Five of the resected patients were in stage IVA and five in stage IVB. After tumor resection, patients lived longer than those who underwent local or systemic treatment only (p = 0.003 or p = 0.001, respectively). In the univariate survival analysis, the stage IV patients' long-term survival was decreased statistically significantly through elevated bilirubin, low albumin, Okuda stage III and BCLC stage D. Patients' age and sex, pre-treatment AFP level, Child stage and the presence of venous invasion did not influence survival. In the multivariate analysis (Cox regression), tumor resection and BCLC stage were independent prognostic factors. CONCLUSION: Patients with HCC in TNM stage IV have a very poor prognosis. Only few patients are eligible for resection because of the extent of tumor growth, comorbidities and general condition. These, however, benefit markedly from tumor resection with lymph node dissection and possibly resection of distant metastases.


Assuntos
Carcinoma Hepatocelular/mortalidade , Neoplasias Hepáticas/mortalidade , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/cirurgia , Feminino , Hepatectomia , Humanos , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/cirurgia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Análise de Sobrevida , Adulto Jovem
14.
Zentralbl Chir ; 141(5): 559-564, 2016 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-23824621

RESUMO

Since the first living donor liver transplantations at the end of the 1980s, this transplantation technique has developed as an established tool within the modern transplantation medicine. Especially in Asia, the majority of liver transplantation is performed through living donation, mainly for religious reasons. Liver grafts for adult recipients are mainly the right liver lobe of the donor, for paediatric recipients mainly the left lateral lobe. In some cases, the living donor liver transplantation is realised from two different donors for one recipient, the so-called "dual graft" transplantation. This article summarises the history of living donor liver transplantation up to the current status of this transplantation procedure worldwide.


Assuntos
Transplante de Fígado/métodos , Transplante de Fígado/tendências , Doadores Vivos , Adulto , Criança , Previsões , Alemanha , Humanos , Obtenção de Tecidos e Órgãos/tendências
17.
Z Rheumatol ; 74(3): 246-9, 2015 Apr.
Artigo em Alemão | MEDLINE | ID: mdl-25644068

RESUMO

CASE REPORT: This article presents an overview of the typical clinical and imaging features of relapsing polychondritis (RP), a rare autoimmune disease, based on a case report CONCLUSION: Although the diagnosis is mainly established clinically, the use of (18)F fluorodeoxyglucose positron emission tomography-computed tomography ((18)F-FDG-PET/CT) has been proven to be a useful diagnostic tool to accurately determine the extent of inflammation throughout the body [corrected]. Furthermore (18)F-FDG-PET/CT provides a high sensitivity for detection of a relapse, especially when clinical and laboratory results are inconclusive. Additionally, (18)F-FDG-PET/CT helps to assess disease activity during the course of therapy.


Assuntos
Fluordesoxiglucose F18 , Aumento da Imagem/métodos , Imagem Multimodal/métodos , Policondrite Recidivante/diagnóstico , Tomografia por Emissão de Pósitrons/métodos , Tomografia Computadorizada por Raios X/métodos , Diagnóstico Diferencial , Seguimentos , Humanos , Compostos Radiofarmacêuticos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
18.
Chirurg ; 85(9): 806-11, 2014 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-24449083

RESUMO

INTRODUCTION: Even in patients with a history of solid malignant tumors, especially of gastrointestinal origin, newly diagnosed solid liver lesions do not necessarily correspond to metastases of the respective primary tumor. A reliable diagnosis can only be made by definitive histological examination. MATERIAL AND METHODS: Data of all patients who underwent liver resection under the preoperative diagnosis of liver metastases between 1997 and 2011 and for whom liver specimens were examined histologically, were extracted from the prospectively maintained cancer registry. RESULTS: An unexpected histological result occurred in 47 out of 770 patients (6.1 %). Primary tumors in these patients included renal cell (n=12), colorectal (n=11), breast (n=8), gastric (n=4), pancreatic (n=3), skin (n=3) and other cancers (n=6). Liver lesions were diagnosed synchronously in 15 cases or metachronously after a median of 17 months following primary therapy in 32 patients. Histology revealed a benign tumor in 38 cases (81 %) as well as 6 cases of HCC, 2 cases of CCC and in 1 case metastasis of a previously unknown colorectal cancer in a patient with known esophageal carcinoma. Suspicion of metastatic disease was based on four different imaging modalities in two cases and on three different imaging modalities in nine cases. Either computed tomography (CT) or magnetic resonance imaging (MRI) was combined with ultrasound in another 23 patients and with positron emission tomography (PET) CT in 6 more cases. In two patients CT plus MRI and CT only, respectively, was performed. In the remaining three patients, suspicion of metastases occurred intraoperatively after macroscopic examination of the liver. Preoperative percutaneous biopsy was attempted in four patients with indeterminate results. CONCLUSION: Even with modern diagnostics the risk of treating a benign or other form of malignant tumor with neoadjuvant or palliative chemotherapy persists. The same holds true for local ablative procedures. Prior to local ablation or definitive palliative chemotherapy histological confirmation of metastases should be attempted.


Assuntos
Antineoplásicos/uso terapêutico , Hepatectomia , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/secundário , Neoplasias Hepáticas/terapia , Neoplasias Primárias Múltiplas/diagnóstico , Neoplasias Primárias Múltiplas/terapia , Segunda Neoplasia Primária/diagnóstico , Segunda Neoplasia Primária/terapia , Diagnóstico Diferencial , Feminino , Humanos , Fígado/patologia , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante , Neoplasias Primárias Múltiplas/patologia , Segunda Neoplasia Primária/patologia , Cuidados Paliativos , Prognóstico , Estudos Prospectivos , Sistema de Registros
19.
Zentralbl Chir ; 139 Suppl 2: e25-34, 2014 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-22274918

RESUMO

INTRODUCTION: Despite a rising incidence worldwide, cholangiocarcinoma (CCC) is one of the infrequent malignancies of the gastrointestinal tract. The surgical approach depends largely on the location of the tumour. PATIENTS AND METHODS: Since 1995, 425 consecutive patients with cholangiocarcinoma were seen at our hospital; their data were prospectively entered in our cancer registry. Tumour-specific data were now retrospectively analysed for prognostic value. RESULTS: Resection with primarily curative intent was performed in 183 of the 425 patients; resection rates were 36 % for intrahepatic (66 patients), 44 % for hilar (69 patients) and 56 % for distal cholangiocarcinoma (48 patients). R0-resection was achieved in 152 patients (83 %) and was found to be the most important factor determining survival. With respect to intrahepatic cholangiocarcinoma, clinical T3- and T4-categories, lymph node metastases as well as UICC stages III and IV had negative predictive value; in hilar carcinomas, this was only seen for the last two factors. In distal cholangiocarcinoma, a low degree of differentiation was associated with a poor prognosis. No differences in survival were seen in the presence of perineural infiltration, angioinvasion or elevation of tumour marker CA 19 - 9.  Regarding the surgical techniques, we found a survival benefit for limited liver resection in intrahepatic cholangiocarcinomas, which is explained by earlier tumour stages seen in these cases, as well as the performance of trisectionectomy or liver transplantation in hilar carcinomas. CONCLUSIONS: Comparable to other malignant gastrointestinal tumours, radical surgery represents the most important prognostic factor in cholangiocarcinomas; for hilar tumours, a survival advantage is seen after extended resections (trisectionectomy or liver transplantation) if compared to more limited resections. At the time of presentation, however, the stage of disease was incurable in most patients, thus accounting for the low overall resection rates.


Assuntos
Neoplasias dos Ductos Biliares/diagnóstico , Neoplasias dos Ductos Biliares/cirurgia , Ductos Biliares Intra-Hepáticos/cirurgia , Colangiocarcinoma/diagnóstico , Colangiocarcinoma/cirurgia , Hepatectomia/métodos , Complicações Pós-Operatórias/etiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias dos Ductos Biliares/mortalidade , Neoplasias dos Ductos Biliares/patologia , Ductos Biliares Intra-Hepáticos/patologia , Biomarcadores Tumorais/sangue , Colangiocarcinoma/mortalidade , Colangiocarcinoma/patologia , Diagnóstico Diferencial , Feminino , Humanos , Fígado/patologia , Masculino , Pessoa de Meia-Idade , Sistema de Registros , Estudos Retrospectivos , Taxa de Sobrevida
20.
Zentralbl Chir ; 138(4): 442-8, 2013 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-23950080

RESUMO

Extended liver resections are associated with the risk of postoperative liver dysfunction up to liver failure. For this reason, prior to extended liver resections patients are conditioned in multi-modal therapy regimes. Portal vein embolisation is an essential part of such a multi-modal therapy. The aim of this intervention is an induction of hypertrophy of the future remnant liver volume. Thereby, the risk of postoperative liver failure is decreased. This article summarises the actual aspects of portal vein embolisation prior to extended liver resections.


Assuntos
Embolização Terapêutica/tendências , Hepatectomia/métodos , Hepatectomia/tendências , Cirrose Hepática/cirurgia , Neoplasias Hepáticas/cirurgia , Veia Porta , Cuidados Pré-Operatórios , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/cirurgia , Terapia Combinada , Progressão da Doença , Humanos , Fígado/irrigação sanguínea , Cirrose Hepática/diagnóstico , Cirrose Hepática/mortalidade , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/secundário , Reoperação , Análise de Sobrevida
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