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1.
Mol Oncol ; 2024 Sep 01.
Article in English | MEDLINE | ID: mdl-39219164

ABSTRACT

Intraductal papillary mucinous neoplasms (IPMNs) are potential precursor lesions of pancreatic cancer. We assessed the efficacy of screening for KRAS proto-oncogene, GTPase (KRAS), and GNAS complex locus (GNAS) mutations in cell-free DNA (cfDNA)-using digital droplet polymerase chain reaction (ddPCR) and circulating epithelial cell (CEC) detection-as biomarkers for risk stratification in IPMN patients. We prospectively collected plasma samples from 25 resected patients at risk of malignant progression, and 23 under clinical surveillance. Our findings revealed KRAS mutations in 10.4% and GNAS mutations in 18.8% of the overall cohort. Among resected IPMN patients, KRAS and GNAS mutation detection rates were 16.0% and 32.0%, respectively, whereas both rates were 4.0% in conservatively managed IPMN. GNAS mutations in cfDNA were significantly more prevalent in resected IPMN (P = 0.024) compared with IPMN under surveillance. No CECs were detected. The absence of KRAS and GNAS mutations could be a reliable marker for branch duct IPMN without worrisome features. The emergence of GNAS mutations could prompt enhanced imaging surveillance. Neither the presence of established worrisome features nor GNAS or KRAS mutations appear effective in identifying high-grade dysplasia among IPMN patients.

2.
J Clin Oncol ; 42(26): 3094-3104, 2024 Sep 10.
Article in English | MEDLINE | ID: mdl-38843469

ABSTRACT

PURPOSE: First-line therapy options in advanced cholangiocarcinoma (CCA) are based on the ABC-02 trial regimen (gemcitabine/cisplatin [G/C]). The NIFE trial examined nanoliposomal irinotecan/fluorouracil/leucovorin (nal-IRI/FU/LV) as alternative first-line therapy in advanced CCA. METHODS: NIFE is a prospective, open-label, randomized, multicenter phase II study that aimed at detecting efficacy comparable with the standard treatment. Patients with advanced CCA were randomly assigned (1:1) to receive nal-IRI/FU/LV (arm A) or G/C (arm B). Stratification parameters were intrahepatic versus extrahepatic CCA, sex, and Eastern Cooperative Oncology Group (ECOG; 0/1). Arm A was designed as a Simon's optimal two-stage design and arm B served as a randomized control group. The primary goal was to exclude an inferior progression-free survival (PFS) at 4 months of only 40%, while assuming a rate of 60% on G/C population. RESULTS: Between 2018 and 2020, overall 91 patients were randomly assigned to receive nal-IRI/FU/LV (n = 49) or G/C (n = 42). The NIFE trial formally met its primary end point with a 4-month PFS rate of 51% in patients receiving nal-IRI/FU/LV. The median PFS was 6 months (2.4-9.6) in arm A and 6.9 months (2.5-7.9) in arm B. Median overall survival (OS) was 15.9 months (10.6-20.3) in arm A and 13.6 months (6.5-17.7) in arm B. The exploratory comparison of study arms suggested a numerical but statistically not significant advantage for nal-IRI/FU/LV (hazard ratio for PFS, 0.85 [95% CI, 0.53 to 1.38] and for OS, 0.94 [95% CI, 0.58 to 1.50]). Analysis for stratification parameters revealed no differences for sex and ECOG, but for tumor localization. The objective response rate was 24.5% with nal-IRI/FU/LV and 11.9% with G/C. No unexpected toxicities occurred. AEs related to nal-IRI/FU/LV were mainly GI and to G/C hematologic. CONCLUSION: Treatment of advanced CCA with nal-IRI/FU/LV demonstrated efficacy in first-line therapy without new safety findings and merits further validation.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols , Bile Duct Neoplasms , Cholangiocarcinoma , Cisplatin , Deoxycytidine , Fluorouracil , Gemcitabine , Irinotecan , Leucovorin , Liposomes , Humans , Male , Female , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Cholangiocarcinoma/drug therapy , Cholangiocarcinoma/pathology , Middle Aged , Leucovorin/administration & dosage , Leucovorin/adverse effects , Fluorouracil/administration & dosage , Irinotecan/administration & dosage , Irinotecan/adverse effects , Deoxycytidine/analogs & derivatives , Deoxycytidine/administration & dosage , Deoxycytidine/adverse effects , Aged , Cisplatin/administration & dosage , Cisplatin/adverse effects , Bile Duct Neoplasms/drug therapy , Bile Duct Neoplasms/pathology , Prospective Studies , Adult , Progression-Free Survival
3.
PLoS One ; 19(6): e0304324, 2024.
Article in English | MEDLINE | ID: mdl-38875244

ABSTRACT

BACKGROUND: Anti-vascular endothelial growth factor (VEGF) monoclonal antibodies (mAbs) are widely used for tumor treatment, including metastatic colorectal cancer (mCRC). So far, there are no biomarkers that reliably predict resistance to anti-VEGF mAbs like bevacizumab. A biomarker-guided strategy for early and accurate assessment of resistance could avoid the use of non-effective treatment and improve patient outcomes. We hypothesized that repeated analysis of multiple cytokines and angiogenic growth factors (CAFs) before and during treatment using machine learning could provide an accurate and earlier, i.e., 100 days before conventional radiologic staging, prediction of resistance to first-line mCRC treatment with FOLFOX plus bevacizumab. PATIENTS AND METHODS: 15 German and Austrian centers prospectively recruited 50 mCRC patients receiving FOLFOX plus bevacizumab as first-line treatment. Plasma samples were collected every two weeks until radiologic progression (RECIST 1.1) as determined by CT scans performed every 2 months. 102 pre-selected CAFs were centrally analyzed using a cytokine multiplex assay (Luminex, Myriad RBM). RESULTS: Using random forests, we developed a predictive machine learning model that discriminated between the situations of "no progress within 100 days before radiological progress" and "progress within 100 days before radiological progress". We could further identify a combination of ten out of the 102 CAF markers, which fulfilled this task with 78.2% accuracy, 71.8% sensitivity, and 82.5% specificity. CONCLUSIONS: We identified a CAF marker combination that indicates treatment resistance to FOLFOX plus bevacizumab in patients with mCRC within 100 days prior to radiologic progress.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols , Bevacizumab , Colorectal Neoplasms , Drug Resistance, Neoplasm , Fluorouracil , Leucovorin , Organoplatinum Compounds , Humans , Colorectal Neoplasms/drug therapy , Colorectal Neoplasms/pathology , Bevacizumab/therapeutic use , Bevacizumab/administration & dosage , Leucovorin/therapeutic use , Leucovorin/administration & dosage , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Female , Organoplatinum Compounds/therapeutic use , Organoplatinum Compounds/administration & dosage , Male , Fluorouracil/therapeutic use , Fluorouracil/administration & dosage , Middle Aged , Aged , Prospective Studies , Adult , Neoplasm Metastasis , Biomarkers, Tumor/blood
4.
PhytoKeys ; 241: 65-79, 2024.
Article in English | MEDLINE | ID: mdl-38638578

ABSTRACT

The new species, Thliphthisasapphussp. nov. (Rubiaceae, Rubieae), a narrow endemic of the white cliffs of Lefkátas on the southwest coast of Lefkada (Greece) is described and illustrated and an IUCN assessment is presented. Vegetation relevés were performed at the single known locality, limestone cliffs facing the sea and revealed a new association, the Thliphthisasapphus-Lomelosietumdallaportae. The chromosome number of Thliphthisasapphus was determined as 2n = 4x = 44, being the single tetraploid species in the genus to date. The species also differs markedly morphologically from its morphologically closest relatives, two Greek steno-endemic oreophytes, Th.baenitzii and Th.muscosa by the following characters: densely setose mericarps and corolla, tetraploidy and by its distribution. An identification key for the Greek species of Thliphthisa is provided. Th.sapphus constitutes the westernmost outpost of a group of Greek steno-endemics, highlighting the importance of coastal habitats and their protection as refugia for poorly competitive chamaephytes.

5.
Article in German | MEDLINE | ID: mdl-38334785

ABSTRACT

Intellectual disability has a prevalence rate of approximately 1% of the population; in Germany, this is around 0.5-1 million people. The life expectancy of this group of people is reduced, with cancer being one of the most common causes of death (approx. 20%). Overall, the risk of cancer and mortality is increased compared to the general population.Certain genetic syndromes predispose to cancer in this vulnerable group, but associated comorbidities or lifestyle could also be risk factors for cancer. People with cognitive impairments are less likely to attend preventive check-ups, and challenges arise in medical care due to physical, communicative, and interactional characteristics. Optimized cooperation between clinical centers for people with disabilities and the respective cancer centers is required in order to tailor the processes to the individual.In Germany, there is a lack of data on the prevalence of cancer entities and the use and need for healthcare services. There is an urgent need to focus attention on cancer prevention, treatment, and research in the vulnerable and heterogeneous group of people with intellectual disabilities suffering from cancer in order to effectively counteract the increase in cancer-related deaths in this population group.The article summarizes specialist knowledge on cancer in people with an intellectual disability, identifies special features of treatment, presents care structures, and derives specific requirements for clinics and research.


Subject(s)
Intellectual Disability , Neoplasms , Humans , Intellectual Disability/diagnosis , Intellectual Disability/epidemiology , Intellectual Disability/genetics , Prevalence , Germany/epidemiology , Delivery of Health Care , Life Expectancy , Neoplasms/epidemiology , Neoplasms/genetics , Neoplasms/therapy
6.
Clin Genitourin Cancer ; 22(2): 458-466.e1, 2024 04.
Article in English | MEDLINE | ID: mdl-38267304

ABSTRACT

INTRODUCTION: Two randomized trials demonstrated a survival benefit of triplet therapy (androgen deprivation therapy [ADT]) plus androgen receptor pathway inhibitor [ARPI] plus docetaxel) over doublet therapy (ADT plus docetaxel), thus changing treatment strategies in metastatic hormonesensitive prostate cancer (mHSPC). PATIENTS AND METHODS: We conducted the first real-world analysis comprising 97 mHSPC patients from 16 Austrian medical centers, among them 79.4% of patients received abiraterone and 17.5% darolutamide treatment. Baseline characteristics and clinical parameters during triplet therapy were documented. Mann-Whitney U test for continuous or X²-test for categorical variables was used. Variables on progression were tested using logistic regression analysis and tabulated as hazard ratios (HR), 95% confidence interval (CI). RESULTS: Of 83.5% patients with synchronous and 16.5% with metachronous disease were included. 83.5% had high-volume disease diagnosed by conventional imaging (48.9%) or PSMA PET-CT (51.1%). While docetaxel and ARPI were administered consistent with pivotal trials, prednisolone, prophylactic gCSF and osteoprotective agents were not applied guideline conform in 32.5%, 37%, and 24.3% of patients, respectively. Importantly, a nonsimultaneous onset of chemotherapy and ARPI, performed in 44.3% of patients, was associated with significantly worse treatment response (P = .015, HR 0.245). Starting ARPI before chemotherapy was associated with significantly higher probability for progression (P = .023, HR 15.781) than vice versa. Strikingly, 15.6% (abiraterone) and 25.5% (darolutamide) low-volume patients as well as 14.4% (abiraterone) and 17.6% (darolutamide) metachronous patients received triplet therapy. Adverse events (AE) occurred in 61.9% with grade 3 to 5 in 15% of patient without age-related differences. All patients achieved a PSA decline of 99% and imaging response was confirmed in 88% of abiraterone and 75% of darolutamide patients. CONCLUSIONS: Triplet therapy arrived in clinical practice primarily for synchronous high-volume mHSPC. Regardless of selected therapy regimen, treatment is highly effective and tolerable. Preferably therapy should be administered simultaneously, however if not possible, chemotherapy should be started first.


Subject(s)
Prostatic Neoplasms , Humans , Male , Androgen Antagonists/therapeutic use , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Austria , Docetaxel/therapeutic use , Hormones , Positron Emission Tomography Computed Tomography , Prostatic Neoplasms/drug therapy , Prostatic Neoplasms/pathology , Randomized Controlled Trials as Topic
7.
Z Gastroenterol ; 62(2): 175-182, 2024 Feb.
Article in English | MEDLINE | ID: mdl-36669527

ABSTRACT

OBJECTIVES: Endoscopic trans-anal colonic decompression (ECD) may be requested in the case of massive colon distension, but evidence regarding success and safety issues remains scarce. The aim of this analysis is to examine the technical success, complications and clinical outcome in a large series of patients undergoing an ECD in various clinical scenarios. A standardized evaluation system was used to identify the pre-interventional risk parameters that might be helpful to guide clinical decision making. METHODS: In this single-centre retrospective study, the modified Clavien-Dindo classification (CDC) was applied to assess technical success, complications and clinical outcome of 125 consecutive patients who underwent ECD between 2007 and 2020. PRIMARY ENDPOINT: post interventional 90-day mortality. Secondary endpoints: periprocedural complications (CDC event IV-V) and technical success rate. All Martin criteria for standardized reporting of complications were met. Uni- and multivariable analyses for prediction of complications were carried out. RESULTS: The overall technical success rate was 90%. The periprocedural complication rate was low with 3%. Overall 90-day mortality was 31%. Univariable analyses showed a significant correlation between 90-day mortality and ASA≥4 (p<0.001, odds ratio [OR] 15.33), general anaesthesia (p=0.05, OR 21.42) and elevated serological infection parameters (p 0.028, OR 1.004). The pre-interventional multivariable model identified ASA ≥4 (p <0.001; OR 10.94) as the only independent risk factor. CONCLUSIONS: ECD is a safe, easily available, technical feasible, inexpensive and successful tool for colonic decompression in various colonic obstruction scenarios, even in critically ill patients. ASA Score ≥IV can be helpful to identify patients at risk for complications/mortality after ECD.


Subject(s)
Endoscopy , Intestinal Obstruction , Humans , Retrospective Studies , Colon , Decompression/adverse effects
8.
Nat Commun ; 14(1): 6927, 2023 Oct 30.
Article in English | MEDLINE | ID: mdl-37903762

ABSTRACT

Seeking to enhance the strength of the interlayer Dzyaloshinskii-Moriya interaction (IL-DMI) through a combination of atomic and Rashba type spin-orbit coupling (SOC) we studied the strength and the thickness evolution of effective interlayer coupling in Co/Ag/Co trilayers by means of surface sensitive magneto-optical measurements that take advantage of the light penetration depth. Here, we report the observation of oscillatory, thickness-dependent chiral interaction between ferromagnetic layers. Despite the weakness of the Ag atomic SOC, the IL-DMI in our trilayers is orders of magnitude larger than that of known systems using heavy metals as a spacer except of recently reported -0.15 mJ/m2 in Co/Pt/Ru(t)/Pt/Co and varies between ≈ ±0.2 mJ/m2. In contrast to known multilayers Co/Ag/Co promotes in-plane chirality between magnetic layers. The strength of IL-DMI opens up new routes for design of three-dimensional chiral spin structures combining intra- and interlayer DMI and paves the way for enhancements of the DMI strength.

9.
PhytoKeys ; 221: 95-116, 2023.
Article in English | MEDLINE | ID: mdl-37250353

ABSTRACT

Psychotriaphilippensis (Rubiaceae) was described by Chamisso and Schlechtendal in 1829, was the first Psychotria name published for the Philippines and is currently considered a Philippine endemic. The name remained in a taxonomic limbo for almost two centuries as it was variously accepted, synonymized or considered obscure, probably because the type specimen in the Berlin herbarium was destroyed and no original material has survived or is currently known. A combined analysis of the information on morphology, type locality and ecology contained in the protologue and a review of relevant literature on the study of the name by various authors over the last two centuries finally clarified the identity of P.philippensis. The name is confirmed here as a synonym of the rubiaceous mangrove Scyphiphorahydrophylacea, as first proposed by Schumann, one of the authorities of the family in the late 19th century, and the application of P.philippensis is fixed by neotypification. This reduces the number of Philippine species of Psychotria by one, but fortunately, this is not happening through extinction, as has been the case with too many species of the highly endangered Philippine flora. In addition, the history of the discovery and study of S.hydrophylacea and its synonyms are described in detail, and one lectotype and one neotype are designated.

10.
Molecules ; 27(21)2022 Oct 26.
Article in English | MEDLINE | ID: mdl-36364108

ABSTRACT

There is a previously neglected influence of geochemical conditions on plant phytochemistry. In particular, high concentrations of dissolved salts can affect their biosynthesis of natural products. Detoxification is most likely an important aspect for the plant, but additional natural products can also give it an expanded range of bioactivities. During the phytochemical analysis a Palicourea luxurians plant collected in a sulfate-rich environment (near the Río Sucio, Costa Rica) showed an interesting natural product in this regard. The structure of this compound was determined using spectroscopic and computational methods (NMR, MS, UV, IR, CD, optical rotation, quantum chemical calculations) and resulted in a megastigmane sulfate ester possessing a ß-ionone core structure, namely blumenol C sulfate (1, C13H22O5S). The levels of sulfur and sulfate ions in the leaves of the plant were determined using elemental analysis and compared to the corresponding levels in comparable plant leaves from a less sulfate-rich environments. The analyses show the leaves from which we isolated blumenol C sulfate (1) to contain 35% more sulfur and 80% more sulfate than the other samples. Antimicrobial and antioxidant activities of compound 1 were tested against Escherichia coli, E. coli ampR and Bacillus subtilis as well as measured using complementary in vitro FRAP and ATBS assays, respectively. These bioactivities are comparable to those determined for structurally related megastigmanes. The sulfur and sulfate content of the plant leaves from the sulfate-rich environment was significantly higher than that of the other plants. Against this background of salt stress, we discuss a possible biosynthesis of blumenol C sulfate (1). Furthermore, there appears to be no benefit for the plant in terms of extended bioactivities. Hence, the formation of blumenol C sulfate (1) probably primarily serves the plant detoxification process.


Subject(s)
Biological Products , Rubiaceae , Rubiaceae/chemistry , Norisoprenoids/analysis , Sulfates/analysis , Escherichia coli , Plant Leaves/chemistry , Biological Products/analysis , Sulfur/analysis
11.
Am J Gastroenterol ; 117(6): 884-894, 2022 06 01.
Article in English | MEDLINE | ID: mdl-35213393

ABSTRACT

INTRODUCTION: Preclinical, epidemiological, and small clinical studies suggest that green tea extract (GTE) and its major active component epigallocatechingallate (EGCG) exhibit antineoplastic effects in the colorectum. METHODS: A randomized, double-blind trial of GTE standardized to 150 mg of EGCG b.i.d. vs placebo over 3 years was conducted to prevent colorectal adenomas (n = 1,001 with colon adenomas enrolled, 40 German centers). Randomization (1:1, n = 879) was performed after a 4-week run-in with GTE for safety assessment. The primary end point was the presence of adenoma/colorectal cancer at the follow-up colonoscopy 3 years after randomization. RESULTS: The safety profile of GTE was favorable with no major differences in adverse events between the 2 well-balanced groups. Adenoma rate in the modified intention-to-treat set (all randomized participants [intention-to-treat population] and a follow-up colonoscopy 26-44 months after randomization; n = 632) was 55.7% in the placebo and 51.1% in the GTE groups. This 4.6% difference was not statistically significant (adjusted relative risk 0.905; P = 0.1613). The respective figures for the per-protocol population were 54.3% (151/278) in the placebo group and 48.3% (129/267) in the GTE group, indicating a slightly lower adenoma rate in the GTE group, which was not significant (adjusted relative risk 0.883; P = 0.1169). DISCUSSION: GTE was well tolerated, but there was no statistically significant difference in the adenoma rate between the GTE and the placebo groups in the whole study population.


Subject(s)
Adenoma , Colorectal Neoplasms , Adenoma/prevention & control , Antioxidants/therapeutic use , Colorectal Neoplasms/prevention & control , Double-Blind Method , Humans , Plant Extracts/therapeutic use , Tea
12.
Dig Dis ; 40(2): 223-231, 2022.
Article in English | MEDLINE | ID: mdl-33866312

ABSTRACT

BACKGROUND: Early detection of liver cirrhosis is crucial for secondary prevention of complications. However, noninvasive blood-based patient monitoring tools are lacking. In this explorative study, we conducted a targeted metabolomic analysis in order to identify possible serum markers indicating alcoholic liver cirrhosis (aLiC) with or without hepatocellular carcinoma (HCC). METHODS: Venous blood of 30 individuals was collected: healthy controls ("Con", n = 12), patients with aLiC without and with HCC ("aLiC": n = 6 and "aLiC + HCC": n = 6), and patients with other liver diseases ("oLiD": n = 6). A targeted metabolomic analysis was conducted using the AbsoluteIDQ® p180 Kit (Biocrates Life Sciences®, Innsbruck, Austria). Statistical analysis was performed by applying a one-way ANOVA on all subgroups followed by a t test for pairwise comparison of subgroups and logistic regression analysis. RESULTS: ANOVA revealed 29 metabolites that significantly discriminate between the different cohorts. Among these analytes, 25 were significantly altered in Con versus aLiC, as indicated by t test, most importantly SM C18:1 (p < 0.001), SM C20:2 (p = 0.001), SM (OH) C22:2 (p < 0.001), lysoPC a C20:4 (p < 0.001), and PC aa C36:5 (p < 0.001). To a similar extent, the metabolites discriminated also between the oLiD and aLiC but less between the Con or oLiD and aLiC + HCC cohorts. Most of these analytes were either lyso- and phosphatidylcholines or sphingomyelins. Results were not significant for comparison of Con versus oLiD and aLiC versus aLiC + HCC. CONCLUSION: Decreased lyso- and phosphatidylcholine as well as sphingomyelin species in venous blood could help to detect liver cirrhosis in patients with non-cirrhotic liver disease.


Subject(s)
Carcinoma, Hepatocellular , Liver Neoplasms , Carcinoma, Hepatocellular/diagnosis , Humans , Liver Cirrhosis/diagnosis , Liver Cirrhosis, Alcoholic/diagnosis , Liver Neoplasms/diagnosis , Metabolomics/methods
13.
Cancers (Basel) ; 13(21)2021 Oct 27.
Article in English | MEDLINE | ID: mdl-34771540

ABSTRACT

We conducted a retrospective National Cancer Registry study in Austria to assess a possible seasonal variation in the clinical diagnosis of testicular germ cell tumors (TGCT). In total, 3615 testicular cancer diagnoses were identified during an 11-year period from 2008 to 2018. Rate ratios for the monthly number of TGCT diagnoses, as well as of seasons and half-years, were assessed using a quasi-Poisson model. We identified, for the first time, a statistically significant seasonal trend (p < 0.001) in the frequency of monthly newly diagnosed cases of TGCT. In detail, clear seasonal variations with a reduction in the tumor incidence during the summer months (Apr-Sep) and an increase during the winter months (Oct-Mar) were observed (p < 0.001). Focusing on seasonality, the incidence during the months of Oct-Dec (p = 0.008) and Jan-Mar (p < 0.001) was significantly higher compared to the months of Jul-Sep, respectively. Regarding histopathological features, there is a predominating incidence in the winter months compared to summer months, mainly concerning pure seminomas (p < 0.001), but not the non-seminoma or mixed TGCT groups. In conclusion, the incidence of TGCT diagnoses in Austria has a strong seasonal pattern, with the highest rate during the winter months. These findings may be explained by a delay of self-referral during the summer months. However, the hypothetical influence of vitamin D3 in testicular carcinogenesis underlying seasonal changes in TGCT diagnosis should be the focus of further research.

14.
Phys Rev Lett ; 127(14): 147201, 2021 Oct 01.
Article in English | MEDLINE | ID: mdl-34652169

ABSTRACT

We demonstrate a nanoscale materials design path that allows us to bypass universality in thin ferromagnetic films and enables us to tune the critical exponents of ferromagnetic phase transitions in a very wide parameter range, while at the same time preserving scaling in an extended phase space near the Curie temperature. Our detailed magnetometry results reveal that single crystal CoRu alloy films, in which the predefined depth dependent exchange coupling strength follows a V-shaped profile, exhibit critical scaling behavior over many orders of magnitude. Their critical exponents, however, can be designed and controlled by modifying their specific nanoscale structures, thus demonstrating full tunability of critical behavior. The reason for this tunability and the disappearance of universality is shown to be the competing relevance of collective versus interface propagating progression of ferromagnetic phase transitions, whose balance we find to be dependent on the specifics of the underlying exchange coupling strength profile.

15.
Insects ; 12(8)2021 Jul 31.
Article in English | MEDLINE | ID: mdl-34442254

ABSTRACT

Natural history collections provide an invaluable basis for systematics, ecology, and conservation. Besides being an important source of DNA, museum specimens may also contain a plethora of natural products. Especially, dried insect collections represent a global repository with billions of inventoried vouchers. Due to their vast diversity, insects possess a great variety of defensive compounds, which they either produce autogenously or derive from the environment. Here, we present a case study on fireflies (Coleoptera: Lampyridae), which produce bufadienolides as a defense against predators. These toxins belong to the cardiotonic steroids, which are used for the treatment of cardiac diseases and specifically inhibit the animal enzyme Na+/K+-ATPase. Bufadienolides have been reported from only seven out of approximately 2000 described firefly species. Using a non-destructive approach, we screened 72 dry coleopteran specimens for bufadienolides using HPLC-DAD and HPLC-MS. We found bufadienolides including five novel compounds in 21 species of the subfamily Lampyrinae. The absence of bufadienolides in the phylogenetically related net-winged beetles (Lycidae) and the lampyrid subfamilies Luciolinae and Lamprohizinae indicates a phylogenetic pattern of bufadienolide synthesis. Our results emphasize the value of natural history collections as an archive of chemical information for ecological and evolutionary basic research and as an untapped source for novel bioactive compounds.

16.
Front Mol Biosci ; 8: 683671, 2021.
Article in English | MEDLINE | ID: mdl-34395523

ABSTRACT

Root-microbe interaction and its specialized root nodule structures and functions are well studied. In contrast, leaf nodules harboring microbial endophytes in special glandular leaf structures have only recently gained increased interest as plant-microbe phyllosphere interactions. Here, we applied a comprehensive metabolomics platform in combination with natural product isolation and characterization to dissect leaf and leaf nodule metabolism and functions in Ardisia crenata (Primulaceae) and Psychotria punctata (Rubiaceae). The results indicate that abiotic stress resilience plays an important part within the leaf nodule symbiosis of both species. Both species showed metabolic signatures of enhanced nitrogen assimilation/dissimilation pattern and increased polyamine levels in nodules compared to leaf lamina tissue potentially involved in senescence processes and photosynthesis. Multiple links to cytokinin and REDOX-active pathways were found. Our results further demonstrate that secondary metabolite production by endophytes is a key feature of this symbiotic system. Multiple anhydromuropeptides (AhMP) and their derivatives were identified as highly characteristic biomarkers for nodulation within both species. A novel epicatechin derivative was structurally elucidated with NMR and shown to be enriched within the leaf nodules of A. crenata. This enrichment within nodulated tissues was also observed for catechin and other flavonoids indicating that flavonoid metabolism may play an important role for leaf nodule symbiosis of A. crenata. In contrast, pavettamine was only detected in P. punctata and showed no nodule specific enrichment but a developmental effect. Further natural products were detected, including three putative unknown depsipeptide structures in A. crenata leaf nodules. The analysis presents a first metabolomics reference data set for the intimate interaction of microbes and plants in leaf nodules, reveals novel metabolic processes of plant-microbe interaction as well as the potential of natural product discovery in these systems.

17.
Int J Cancer ; 148(6): 1428-1437, 2021 03 15.
Article in English | MEDLINE | ID: mdl-32930387

ABSTRACT

Nintedanib is a triple angiokinase inhibitor of vascular endothelial growth factor receptor 1-3, fibroblast growth factor receptor 1-3 and platelet-derived growth factor receptor-a/-b. Thereby, it targets angiogenic escape mechanisms. The trial TyRosine kinase Inhibitor for the treatment of Chemorefractory Colorectal Cancer (TRICC-C) trial evaluates the addition of nintedanib to mFOLFOX6 (fluorouracil, folinic acid and oxaliplatin) in patients with metastatic colorectal cancer (mCRC). TRICC-C is a randomised controlled, double-blinded, phase II trial in mCRC patients that received a first-line non-oxaliplatin containing chemotherapy. Patients received mFOLFOX6 + nintedanib (F + N) (2 × 200 mg p.o./d, d1-d14) or mFOLFOX6 + placebo (F + P), in a 1:1 ratio. Primary endpoint was median progression free survival (mPFS) and secondary overall response rate (ORR), overall survival (OS) and safety. Fifty-three patients (27 F + N; 26 F + P) were randomised between 12/2012 and 5/2016 (scheduled n = 180). The trial was terminated prematurely due to slow accrual. The trial did not reach its primary endpoint but mPFS, median overall survival (mOS) and disease control rate (DCR) were numerically higher in the F + N arm compared to the F + P arm; however, the difference was not significant (mPFS: F + P: 4.6 months vs F + N: 8.1 months; HR 0.65; 95% CI 0.32-1.30; P = .2156; mOS: F + P: 9.9 months vs F + N: 17.1 months; HR 1.03, 95% CI 0.48-2.23; P = .9387; DCR: F + P: 50% vs F + N: 66,7%; P = .2709). Toxicity was moderate and only different for neutropenia (F + P: 11.5%, F + N: 19.2%) and gastrointestinal disorders (F + P: 65.4%, F + N: 84.6%). Final results show safety and a nonsignificant trend towards improved PFS and DCR for the combination of mFOLFOX6 + nintedanib in the second-line therapy of mCRC.


Subject(s)
Adenocarcinoma/drug therapy , Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Colorectal Neoplasms/drug therapy , Drug Resistance, Neoplasm/drug effects , Indoles/administration & dosage , Adenocarcinoma/mortality , Adult , Aged , Colorectal Neoplasms/mortality , Double-Blind Method , Female , Fluorouracil/administration & dosage , Humans , Leucovorin/administration & dosage , Male , Middle Aged , Organoplatinum Compounds/administration & dosage , Progression-Free Survival , Salvage Therapy/methods
18.
Phytochemistry ; 173: 112296, 2020 May.
Article in English | MEDLINE | ID: mdl-32087436

ABSTRACT

The first phytochemical examination of extracts from leaves and stem bark of Palicourea luxurians (Rusby) Borhidi yielded two undescribed and one known alstrostine derivative together with the oxindole alkaloid javaniside as well as with 5α-carboxystrictosidine. Additionally, five iridoids and four secologanin derived isolation artifacts have been isolated. Lack of strictosidine and its follow-up metabolization products suggested that the Pictet-Spenglerase in P. luxurians does barely or not catalyze the formation of strictosidine. Against this background the biosynthesis of javaniside and 5α-carboxystrictosidine is discussed with regard to possible reaction mechanisms. Similarly, P. luxurians used an independent biosynthetic pathway to produce alstrostine type structures from secologanin and tryptamine in a 2:1 ratio. The structure of isoalstrostine A, which was isolated for the first time, allowed the refinement of a previously reported pathway to the alstrostine type carbon skeleton as well as to some follow-up metabolization products. In spite of various biosynthetic pathways incorporating secologanin to gain different types of tryptophan- and tryptamine-iridoid alkaloids, P. luxurians accumulates this compound as well a couple of further metabolized iridoids deriving from loganin and secologanin.


Subject(s)
Alkaloids , Rubiaceae , Secologanin Tryptamine Alkaloids , Iridoid Glucosides , Iridoids , Tryptamines , Tryptophan , Vinca Alkaloids
19.
New Phytol ; 226(1): 267-280, 2020 04.
Article in English | MEDLINE | ID: mdl-31765023

ABSTRACT

Flowers have been hypothesized to contain either modules of attraction and reproduction, functional modules (pollination-effecting parts) or developmental modules (organ-specific). Do pollination specialization and syndromes influence floral modularity? In order to test these hypotheses and answer this question, we focused on the genus Erica: we gathered 3D data from flowers of 19 species with diverse syndromes via computed tomography, and for the first time tested the above-mentioned hypotheses via 3D geometric morphometrics. To provide an evolutionary framework for our results, we tested the evolutionary mode of floral shape, size and integration under the syndromes regime, and - for the first time - reconstructed the high-dimensional floral shape of their most recent common ancestor. We demonstrate that the modularity of the 3D shape of generalist flowers depends on development and that of specialists is linked to function: modules of pollen deposition and receipt in bird syndrome, and access-restriction to the floral reward in long-proboscid fly syndrome. Only size and shape principal component 1 showed multiple-optima selection, suggesting that they were co-opted during evolution to adapt flowers to novel pollinators. Whole floral shape followed an Ornstein-Uhlenbeck (selection-driven) evolutionary model, and differentiated relatively late. Flower shape modularity thus crucially depends on pollinator specialization and syndrome.


Subject(s)
Ericaceae , Flowers , Pollination , Animals , Birds , Pollen
20.
Phys Rev Lett ; 122(25): 257202, 2019 Jun 28.
Article in English | MEDLINE | ID: mdl-31347891

ABSTRACT

The interfacial Dzyaloshinkii-Moriya interaction defines a rotational sense for the spin structure in two-dimensional magnetic films and can be used to create chiral magnetic structures like spin spirals and skyrmions in those films. Here, we show by means of atomistic calculations that in heterostructures an interlayer coupling of the Dzyaloshinskii-Moriya type across a spacer can emerge. We quantify this interaction in the framework of the Lévy-Fert model for trilayers consisting of two ferromagnets separated by a nonmagnetic spacer and show that such an interlayer Dzyaloshinkii-Moriya interaction yields nontrivial three-dimensional spin textures across the entire trilayer, which evolve within as well as between the planes and, hence, combine intraplane and interplane chiralities. This analysis opens new perspectives for three-dimensional tailoring of magnetic chirality in multilayers.

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