This study investigated the efficacy of single-phase dual-energy CT (DECT) in differentiating pulmonary hamartomas from malignant lung lesions using virtual non-contrast (VNC), iodine, and fat ...quantification. Forty-six patients with 47 pulmonary lesions (mean age: 65.2 ± 12.1 years; hamartomas-to-malignant lesions = 22:25; male: 67%) underwent portal venous DECT using histology, PET-CT and follow-up CTs as a reference. Quantitative parameters such as VNC, fat fraction, iodine density and CT mixed values were statistically analyzed. Significant differences were found in fat fractions (hamartomas: 48.9%; malignancies: 22.9%;
≤ 0.0001) and VNC HU values (hamartomas: -20.5 HU; malignancies: 17.8 HU;
≤ 0.0001), with hamartomas having higher fat content and lower VNC HU values than malignancies. CT mixed values also differed significantly (
≤ 0.0001), but iodine density showed no significant differences. ROC analysis favored the fat fraction (AUC = 96.4%; sensitivity: 100%) over the VNC, CT mixed value and iodine density for differentiation. The study concludes that the DECT-based fat fraction is superior to the single-energy CT in differentiating between incidental pulmonary hamartomas and malignant lesions, while post-contrast iodine density is ineffective for differentiation.
PURPOSE Differentiation of incidental adrenal lesions remains a challenge in diagnostic imaging, especially on single-phase portal venous computed tomography (CT) in the oncological setting. The aim ...of the study was to explore the ability of dual-energy CT (DECT)-based iodine quantification and virtual non-contrast (VNC) imaging and advanced radiomic analysis of DECT for differentiation of adrenal adenomas from metastases. METHODS A total of 46 patients with 49 adrenal lesions underwent clinically indicated staging DECT and magnetic resonance imaging. Median values of quantitative parameters such as VNC, fat fraction, and iodine density in DECT images were collected and compared between adenomas and metastases using non-parametric tests. Magnetic resonance imaging, washout CT, and clinical follow-up were used as a reference standard. Diagnostic accuracy was assessed by calculating receiver operating characteristics. A DECT tumor analysis prototype software was used for semiautomatic segmentation of adrenal lesions and extraction of radiomic features. A radiomics prototype was used to analyze the data with multiple logistic regression and random forest classification to determine the area under the curve (AUC). RESULTS The study cohort (60.87% women; mean age: 66.91 + or - 12.93 years) consisted of 32 adenomas and 17 metastases. DECT-based VNC imaging (AUC = 0.89) and fat quantification (AUC = 0.86) differentiate between adrenal adenomas and metastases with high diagnostic accuracy (P < .001). Analysis of radiomic features revealed that DECT features such as VNC imaging and fat fraction (AUC = 0.87-0.89; < .001) and radiomic features such as 90th percentile and total energy (AUC = 0.88-0.93; P < .001) differentiate with high diagnostic accuracy between adrenal adenomas and metastases. Random forest classification revealed an AUC of 0.83 for separating adrenal adenomas from metastases. CONCLUSION Virtual non-contrast imaging and fat quantification as well as extraction of radiomic features accurately differentiate between adrenal adenomas and metastases on single-phase oncologic staging DECT.
Hepatic recurrence of liver malignancies is a leading problem in patients after liver resection with curative intention. Thermoablation is a promising treatment approach for patients after hepatic ...resection, especially in liver-limited conditions. This study aimed to investigate safety, survival, and local tumor control rates of MRI-guided percutaneous thermoablation of recurrent hepatic malignancies following hepatic resection.
Data from patients with primary or secondary hepatic malignancies treated between 2004 and 2018 with MRI-guided percutaneous thermoablation of hepatic recurrence after prior hepatic resection were retrospectively analyzed. Disease-free survival and overall survival rates were calculated using the Kaplan-Meier method.
A total of 57 patients with hepatic recurrence (mean tumor size = 18.9 ± 9.1 mm) of colorectal cancer liver metastases (n = 27), hepatocellular carcinoma (n = 17), intrahepatic recurrence of cholangiocellular carcinoma (n = 9), or other primary malignant tumor entities (n = 4) were treated once or several times with MR-guided percutaneous radiofrequency (n = 52) or microwave ablation (n = 5) (range: 1-4 times). Disease progression occurred due to local recurrence at the ablation site in nine patients (15.8%), non-local hepatic recurrence in 33 patients (57.9%), and distant malignancy in 18 patients (31.6%). The median overall survival for the total cohort was 40 months and 49 months for the colorectal cancer group, with a 5-year overall survival rate of 40.7 and 42.5%, respectively. The median disease-free survival was 10 months for both the total cohort and the colorectal cancer group with a 5-year disease-free survival rate of 15.1 and 14.8%, respectively. The mean follow-up time was 39.6 ± 35.7 months.
MR-guided thermoablation is an effective and safe approach in the treatment of hepatic recurrences in liver-limited conditions and can achieve long-term survival.
The purpose of this study was to evaluate the potential of dual-energy CT (DECT) with virtual unenhanced imaging (VNC) and iodine maps (IM) to differentiate between intraperitoneal hematomas (IH) and ...bowel structures (BS) compared to linearly blended DECT (DE-LB) images (equivalent to single-energy CT). This retrospective study included the DECT of 30 patients (mean age: 64.5 ± 15.1 years, 19 men) with intraperitoneal hematomas and 30 negative controls. VNC, IM, and DE-LB were calculated. Imaging follow-up and surgical reports were used as references. Three readers assessed diagnostic performance and confidence in distinguishing IH and BS for DE-LB, VNC, and IM. Diagnostic confidence was assessed on a five-point Likert scale. The mean values of VNC, IM, and DE-LB were compared with nonparametric tests. Diagnostic accuracy was assessed by calculating receiver operating characteristics (ROC). The results are reported as medians with interquartile ranges. Subjective image analysis showed higher diagnostic performance (sensitivity: 96.7−100% vs. 88.2−96.7%; specificity: 100% vs. 96.7−100%; p < 0.0001; ICC: 0.96−0.99) and confidence (Likert: 5; IRQ 5−5 vs. 4, IRQ 3−4; 4−5; p < 0.0001; ICC: 0.80−0.96) for DECT compared to DE-LB. On objective image analysis, IM values for DECT showed significant differences between IH (3.9 HU; IQR 1.6, 8.0) and BS (39.5 HU; IQR 29.2, 43.3; p ≤ 0.0001). VNC analysis revealed a significantly higher attenuation of hematomas (50.5 HU; IQR 44.4, 59.4) than BS (26.6 HU; IQR 22.8, 32.4; p ≤ 0.0001). DE-LB revealed no significant differences between hematomas (60.5 HU, IQR 52.7, 63.9) and BS (63.9 HU, IQR 58.0, 68.8; p > 0.05). ROC analysis revealed the highest AUC values and sensitivity for IM (AUC = 100%; threshold by Youden-Index ≤ 19 HU) and VNC (0.93; ≥34.1 HU) compared to DE-LB (0.64; ≤63.8; p < 0.001). DECT is suitable for accurate discrimination between IH and BS by calculating iodine maps and VNC images.
Combination therapy using hepatic resection (HR) and intra-operative thermal ablation is a treatment approach for patients with technically unresectable liver malignancies. The aim of this study was ...to investigate safety, survival and local recurrence rates for patients with technically unresectable liver tumors undergoing HR and separate percutaneous MR-guided thermoablation procedure as an alternative approach.
Data from all patients with primary or secondary hepatic malignancies treated at a single institution between 2004 and 2018 with combined HR and MR-guided percutaneous thermoablation was collected and retrospectively analyzed. Complications, procedure related information and patient characteristics were collected from institutional records. Overall survival and disease-free survival were estimated using the Kaplan-Meier method.
A total of 31 patients (age: 62.8 ± 9.1 years; 10 female) with hepatocellular carcinoma (HCC; n = 7) or hepatic metastases (n = 24) were treated for 98 hepatic tumors. Fifty-six tumors (mean diameter 28.7 ± 23.0 mm) were resected. Forty-two tumors (15.1 ± 7.6 mm) were treated with MR-guided percutaneous ablation with a technical success rate of 100%. Local recurrence at the ablation site occurred in 7 cases (22.6%); none of these was an isolated local recurrence. Six of 17 patients (35.3%) treated for colorectal liver metastases developed local recurrence. Five patients developed recurrence at the resection site (16.1%). Non-local hepatic recurrence was observed in 18 cases (58.1%) and extrahepatic recurrence in 11 cases (35.5%) during follow-up (43.1 ± 26.4 months). Ten patients (32.3%) developed complications after HR requiring pharmacological or interventional treatment. No complication requiring therapy was observed after ablation. Median survival time was 44.0 ± 7.5 months with 1-,3-, 5-year overall survival rates of 93.5, 68.7 and 31.9%, respectively. The 1-, 3- and 5-year disease-free survival rates were 38.7, 19.4 and 9.7%, respectively.
The combination of HR and MR-guided thermoablation is a safe and effective approach in the treatment of technically unresectable hepatic tumors and can achieve long-term survival.
The production of African nightshade is below its potential due to a lack of superior varieties. The development of varieties through breeding programmes has been initiated in order to supply farmers ...with quality seeds. However, systematic studies on the agronomic performance of African nightshade germplasm have been started only recently, and publications in this area are very scarce. In this study, we analysed morphological traits relevant for the agronomic performance of 54 entries comprising two species:
Solanum villosum
and
S. scabrum
. In addition, AFLP markers and newly developed SSR markers were used to assess genetic diversity and differentiation in the African nightshade entries. An analysis of molecular variance showed higher variation within than among entries. A cluster analysis grouped the entries into two clusters representing the two species. The analysis of agronomic traits revealed significant differences among entries. The genetic diversity of the released cultivars and accessions was comparable to but lower than that of the local cultivars. Additionally, the local cultivars had higher allelic richness and a larger number of unique alleles than did the developed cultivars and could serve as a useful gene pool for future breeding of superior germplasm.
The genus Helleborus comprises 22 species, which are allocated to six sections. H. x hybridus and H. niger, which belong to different Helleborus sections, are economically important ornamentals. ...Several other species with minor impact exhibit interesting features, e.g. flower size, flower colour, foliage, scent and disease resistance, which should be introgressed into H. x hybridus or H. niger through interspecific hybridisation. The aims of this study were to investigate whether and which kind of hybridisation barriers occur in crosses between Helleborus species and if they differ in their manifestations, depending on the genetic distance of the respective partners. In order to obtain interspecific hybrids despite crossing barriers, a method to overcome these barriers should be developed. Crossing barriers in Helleborus were localised as predominantly post-zygotic according to in situ pollen tube staining with aniline blue. For certain crosses, pre-zygotic barriers could also be assumed, but pollen tube growth was not totally inhibited. Therefore, embryo rescue techniques via ovule culture were established to overcome the post-zygotic barriers. Ovules were isolated from maternal plants 5-7 weeks after pollination in most cases and then cultured in vitro. Overall, 219 hybrids were successfully obtained, of which 16 were derived from inter-sectional crosses. Hybrids were verified by flow cytometry and/or by molecular DNA markers.
Background
Radiofrequency ablation (RFA) is a minimal-invasive, local therapy in patients with circumscribed metastatic disease. Although widely used, long time survival analysis of treated liver ...metastases is still pending while also analysing the patients’ experience of MR-based radiofrequency.
Methods
Monocentric, retrospective analysis of long-time overall and progression free survival (OS; PFS) of 109 patients, treated with MRI-guided hepatic RFA between 1997 and 2010, focusing on colorectal cancer patients (CRC). Complimentary therapies were evaluated and Kaplan Meier-curves were calculated. Patients’ experience of RFA was retrospectively assessed in 28 patients.
Results
1-, 3-, 5-, 10-year OS rates of 109 patients with different tumour entities were 83.4%, 53.4%, 31.0% and 22.9%, median 39.2 months, with decreasing survival rates for larger metastases size. For 72 CRC patients 1-, 3-, 5-, 10-year OS rates of 90.2%, 57.1%, 36.1% and 26.5% were documented (median 39.5 months). Thereof, beneficial outcome was detected for patients with prior surgery of the CRC including chemotherapy (median 53.0 months), and for liver metastases up to 19 mm (28.5% after 145 months). Hepatic PFS was significantly higher in patients with liver lesions up to 29 mm compared to larger ones (
p
= 0.035). 15/28 patients remembered RFA less incriminatory than other applied therapies.
Conclusions
This is the first single-centre, long-time OS and PFS analysis of MRI-guided hepatic RFA of liver metastases from different tumour entities, serving as basis for further comparison studies. Patients’ experience of MR based RFA should be analysed simultaneously to the performed RFA in the future.
Breeding, possibly including polyploidization, in the midday flowers (Aizoaceae) genera Lampranthus and Delosperma is of interest for developing novel drought tolerant bedding plants. However, ...cytological knowledge on these plants is scarce. Flow cytometric investigations on different genotypes of Lampranthus and Delosperma revealed that most organs of these plants predominantly consist of endoreduplicated cells with up to five different DNA contents (2C-32C). Endoreduplication (endocycling) is a process involving one or several rounds of nuclear DNA synthesis without chromosomal and cellular division. The highest proportions of endoreduplicated cells were detected in petaloid staminodes and mature succulent leaves (up to 95%), whereas only relatively low percentages were found in young leaves and roots (≈23-56%). A comparison of greenhouse and in vitro grown plant organs in respect of their endoreduplication patterns only showed marginal differences. How endocycling affects in vitro shoot regeneration and/or chromosome doubling through antimitotic agents remains to be clarified. Further observations on midday flowers of these genera revealed that pollen grains of identical genotypes had various diameters, possibly indicating spontaneous production of unreduced male gametes (2n pollen). In addition microscopic analyses showed that exceptionally large pollen grains also contained larger sperm nuclei. Flow cytometric measurements of pollen nuclei isolated from germinated tricellular grains resulted in the detection of 1C (haploid), 2C and even low percentages of 3C particles. Ongoing microscopic analyses of microsporogenesis, microgametogenesis and the appearance of gametes in pollen tubes should clarify the question whether the detected 2C and 3C signals were caused by unreduced male gametes or physically connected pollen nuclei (male germ units).
Mucopolysaccharidosis II (MPS II) is a rare lysosomal storage disease characterized by deficient activity of iduronate-2-sulfatase (I2S), leading to pathological accumulation of glycosaminoglycans ...(GAGs) in tissues. We used iduronate-2-sulfatase knockout (Ids KO) mice to investigate if liver-directed recombinant adeno-associated virus vectors (rAAV8-LSP-hIDSco) encoding human I2S (hI2S) could cross-correct I2S deficiency in Ids KO mouse tissues, and we then assessed the translation of mouse data to non-human primates (NHPs). Treated mice showed sustained hepatic hI2S production, accompanied by normalized GAG levels in somatic tissues (including critical tissues such as heart and lung), indicating systemic cross-correction from liver-secreted hI2S. Brain GAG levels in Ids KO mice were lowered but not normalized; higher doses were required to see improvements in brain histology and neurobehavioral testing. rAAV8-LSP-hIDSco administration in NHPs resulted in sustained hepatic hI2S production and therapeutic hI2S levels in cross-corrected somatic tissues but no hI2S exposure in the central nervous system, perhaps owing to lower levels of liver transduction in NHPs than in mice. Overall, we demonstrate the ability of rAAV8-LSP-hIDSco to cross-correct I2S deficiency in mouse somatic tissues and highlight the importance of showing translatability of gene therapy data from rodents to NHPs, which is critical for supporting translation to clinical development.
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Chen and colleagues show that gene therapy for mucopolysaccharidosis II through administration of a liver-directed recombinant adeno-associated virus vector encoding human iduronate-2-sulfatase (rAAV8-LSP-hIDSco) is able to cross-correct iduronate-2-sulfatase deficiency in somatic tissues of Ids knockout mice and demonstrate promising translational potential from the mouse model to non-human primates.
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