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1.
Diagnostics (Basel) ; 14(2)2024 Jan 16.
Article in English | MEDLINE | ID: mdl-38248074

ABSTRACT

PURPOSE: Sarcopenia is considered a negative prognostic factor in patients with malignant tumors. Among other diagnostic options, computed tomography (CT), which is repeatedly performed on tumor patients, can be of further benefit. The present study aims to establish a framework for classifying the impact of sarcopenia on the prognosis of patients diagnosed with esophageal or gastric cancer. Additionally, it explores the significance of CT radiomics in both diagnostic and prognostic methodologies. MATERIALS AND METHODS: CT scans of 83 patients with esophageal or gastric cancer taken at the time of diagnosis and during a follow-up period of one year were evaluated retrospectively. A total of 330 CT scans were analyzed. Seventy three of these patients received operative tumor resection after neoadjuvant chemotherapy, and 74% of the patients were male. The mean age was 64 years (31-83 years). Three time points (t) were defined as a basis for the statistical analysis in order to structure the course of the disease: t1 = initial diagnosis, t2 = following (neoadjuvant) chemotherapy and t3 = end of the first year after surgery in the "surgery" group or end of the first year after chemotherapy. Sarcopenia was determined using the psoas muscle index (PMI). The additional analysis included the analysis of selected radiomic features of the psoas major, quadratus lumborum, and erector spinae muscles at the L3 level. Disease progression was monitored according to the response evaluation criteria in solid tumors (RECIST 1.1). CT scans and radiomics were used to assess the likelihood of tumor progression and their correlation to sarcopenia. For machine learning, the established algorithms decision tree (DT), K-nearest neighbor (KNN), and random forest (RF) were applied. To evaluate the performance of each model, a 10-fold cross-validation as well as a calculation of Accuracy and Area Under the Curve (AUC) was used. RESULTS: During the observation period of the study, there was a significant decrease in PMI. This was most evident in patients with surgical therapy in the comparison between diagnosis and after both neoadjuvant therapy and surgery (each p < 0.001). Tumor progression (PD) was not observed significantly more often in the patients with sarcopenia compared to those without sarcopenia at any time point (p = 0.277 to p = 0.465). On average, PD occurred after 271.69 ± 104.20 days. The time from initial diagnosis to PD in patients "with sarcopenia" was not significantly shorter than in patients "without sarcopenia" at any of the time points (p = 0.521 to p = 0.817). The CT radiomics of skeletal muscle could predict both sarcopenia and tumor progression, with the best results for the psoas major muscle using the RF algorithm. For the detection of sarcopenia, the Accuracy was 0.90 ± 0.03 and AUC was 0.96 ± 0.02. For the prediction of PD, the Accuracy was 0.88 ± 0.04 and the AUC was 0.93 ± 0.04. CONCLUSIONS: In the present study, the CT radiomics of skeletal muscle together with machine learning correlated with the presence of sarcopenia, and this can additionally assist in predicting disease progression. These features can be classified as promising alternatives to conventional methods, with great potential for further research and future clinical application. However, when sarcopenia was diagnosed with PMI, no significant correlation between sarcopenia and PD could be observed.

2.
Cancers (Basel) ; 15(23)2023 Nov 29.
Article in English | MEDLINE | ID: mdl-38067334

ABSTRACT

Accurate prediction of lymph node metastasis (LNM) in patients with testicular cancer is highly relevant for treatment decision-making and prognostic evaluation. Our study aimed to develop and validate clinical radiomics models for individual preoperative prediction of LNM in patients with testicular cancer. We enrolled 91 patients with clinicopathologically confirmed early-stage testicular cancer, with disease confined to the testes. We included five significant clinical risk factors (age, preoperative serum tumour markers AFP and B-HCG, histotype and BMI) to build the clinical model. After segmenting 273 retroperitoneal lymph nodes, we then combined the clinical risk factors and lymph node radiomics features to establish combined predictive models using Random Forest (RF), Light Gradient Boosting Machine (LGBM), Support Vector Machine Classifier (SVC), and K-Nearest Neighbours (KNN). Model performance was assessed by the area under the receiver operating characteristic (ROC) curve (AUC). Finally, the decision curve analysis (DCA) was used to evaluate the clinical usefulness. The Random Forest combined clinical lymph node radiomics model with the highest AUC of 0.95 (±0.03 SD; 95% CI) was considered the candidate model with decision curve analysis, demonstrating its usefulness for preoperative prediction in the clinical setting. Our study has identified reliable and predictive machine learning techniques for predicting lymph node metastasis in early-stage testicular cancer. Identifying the most effective machine learning approaches for predictive analysis based on radiomics integrating clinical risk factors can expand the applicability of radiomics in precision oncology and cancer treatment.

3.
Cancers (Basel) ; 14(8)2022 Apr 15.
Article in English | MEDLINE | ID: mdl-35454914

ABSTRACT

Mantle cell lymphoma (MCL) is a rare lymphoid malignancy with a poor prognosis characterised by frequent relapse and short durations of treatment response. Most patients present with aggressive disease, but there exist indolent subtypes without the need for immediate intervention. The very heterogeneous behaviour of MCL is genetically characterised by the translocation t(11;14)(q13;q32), leading to Cyclin D1 overexpression with distinct clinical and biological characteristics and outcomes. There is still an unfulfilled need for precise MCL prognostication in real-time. Machine learning and deep learning neural networks are rapidly advancing technologies with promising results in numerous fields of application. This study develops and compares the performance of deep learning (DL) algorithms and radiomics-based machine learning (ML) models to predict MCL relapse on baseline CT scans. Five classification algorithms were used, including three deep learning models (3D SEResNet50, 3D DenseNet, and an optimised 3D CNN) and two machine learning models based on K-nearest Neighbor (KNN) and Random Forest (RF). The best performing method, our optimised 3D CNN, predicted MCL relapse with a 70% accuracy, better than the 3D SEResNet50 (62%) and the 3D DenseNet (59%). The second-best performing method was the KNN-based machine learning model (64%) after principal component analysis for improved accuracy. Our optimised CNN developed by ourselves correctly predicted MCL relapse in 70% of the patients on baseline CT imaging. Once prospectively tested in clinical trials with a larger sample size, our proposed 3D deep learning model could facilitate clinical management by precision imaging in MCL.

4.
J Subst Abuse Treat ; 138: 108731, 2022 07.
Article in English | MEDLINE | ID: mdl-35125253

ABSTRACT

INTRODUCTION: Opioid overdoses are a major public health emergency in the United States. Despite effective treatments that can save lives, access to and utilization of such treatments are limited. Community context plays an important role in addressing treatment barriers and increasing access. The HEALing Communities Study (HCS) is a multisite community-level cluster-randomized trial that will study implementation and outcomes of a community coalition-based intervention (Communities that HEAL [CTH]) that implements evidence-based practices (EBPs) to reduce opioid overdose deaths in four states. To examine contextual factors critical to understanding implementation, we assessed the perspectives of community members about their communities, current substance use-related services, and other important issues that could impact intervention implementation. METHODS: Researchers conducted 382 semi-structured qualitative interviews in the HCS communities. Interviews were audio-recorded and transcribed; researchers subsequently analyzed data using directed content analysis based on the constructs of the RE-AIM/PRISM implementation science framework to identify key themes within the external community context. RESULTS: Despite the diversity in states and communities, four similar themes related to the external community context emerged across communities: These themes included the importance of understanding: 1) community risk perceptions, 2) levels of stigma, 3) the health services environment and the availability of substance use services, and 4) funding for substance use services. CONCLUSION: Understanding and addressing the external community context in which the CTH intervention and EBPs are implemented are crucial for successful health services-related and community engaged interventions. While implementing EBPs is a challenging undertaking, doing so will help us to understand if and how a community-based intervention can successfully reduce opioid overdose deaths and influence both community beliefs and the community treatment landscape.


Subject(s)
Opiate Overdose , Substance-Related Disorders , Analgesics, Opioid/adverse effects , Evidence-Based Practice , Humans , Opioid Epidemic , Substance-Related Disorders/drug therapy , United States
5.
Chem Biol Drug Des ; 97(1): 77-86, 2021 01.
Article in English | MEDLINE | ID: mdl-32666679

ABSTRACT

A high-throughput screening assay was developed and applied to a large library of natural product extract samples, in order to identify compounds which preferentially inhibited the in vitro 2D growth of a highly metastatic osteosarcoma cell line (MG63.3) compared to a cognate parental cell line (MG63) with low metastatic potential. Evaluation of differentially active natural product extracts with bioassay-guided fractionation led to the identification of lovastatin (IC50  = 11 µm) and the limonoid toosendanin (IC50  = 26 nm). Other statins and limonoids were then tested, and cerivastatin was identified as a particularly potent (IC50  < 0.1 µm) and selective agent. These compounds potently and selectively induced apoptosis in MG63.3 cells, but not MG63. Assays with other cell pairs were used to examine the generality of these results. Statins and limonoids may represent unexplored opportunities for development of modulators of osteosarcoma metastasis. As cerivastatin was previously approved for clinical use, it could be considered for repurposing in osteosarcoma, pending validation in further models.


Subject(s)
Biological Products/pharmacology , Cell Proliferation/drug effects , High-Throughput Screening Assays/methods , Biological Products/chemistry , Biological Products/isolation & purification , Bone Neoplasms/metabolism , Bone Neoplasms/pathology , Cell Line , Cell Movement/drug effects , Cell Survival/drug effects , Drugs, Chinese Herbal/chemistry , Drugs, Chinese Herbal/isolation & purification , Drugs, Chinese Herbal/pharmacology , Humans , Lovastatin/chemistry , Lovastatin/isolation & purification , Lovastatin/pharmacology , Melia/chemistry , Melia/metabolism , Monascus/chemistry , Monascus/metabolism , Osteosarcoma/metabolism , Osteosarcoma/pathology , Plant Extracts/chemistry , Pyridines/chemistry , Pyridines/isolation & purification , Pyridines/pharmacology , Seeds/chemistry , Seeds/metabolism
6.
Sci Total Environ ; 725: 138072, 2020 Jul 10.
Article in English | MEDLINE | ID: mdl-32298896

ABSTRACT

Irrigated dryland agroecosystems could become more sustainable if crop and soil management enhanced soil organic carbon (SOC). We hypothesized that combining high inputs from cover crops with no-tillage will increase long-term SOC stocks. Caatinga shrublands had been cleared in 1972 for arable crops and palm plantations before implementing field experiments on Mango and Melon systems (established in 2009 and 2012, respectively). Each of the two experiments were managed with no-till (NT) or conventional till (CT), and three types of cover cropping, either a plant mixture of 75% (PM1) or 25% (PM2) legumes, or spontaneous vegetation (SV). The RothC model was used with a daily timestep to simulate the soil moisture dynamics and C turnover for this dry climate. Carbon inputs were between 2.62 and 5.82 Mg C ha-1 year-1 and increased the depleted SOC stocks by 0.08 to 0.56 Mg C ha-1 year-1. Scenarios of continuous biomass inputs of ca. 5 Mg C ha-1 year-1 for 60 years are likely to increase SOC stocks in the mango NT beyond the original Caatinga SOC by between 19.2 and 20.5 Mg C ha-1. Under CT similar inputs would increase SOC stocks only marginally above depletion (2.75 to 2.47 Mg C ha-1). Under melon, annual carbon inputs are slightly greater (up to 5.5 Mg C ha-1 year-1) and SOC stocks would increase on average by another 8% to 22.3 to 20.6 Mg C ha-1 under NT and by 8 Mg C ha-1 under CT. These long-term simulations show that combining NT with high quality cover crops (PM1, PM2) would exceed SOC stocks of the initial Caatinga within 20 and 25 years under irrigated melon and mango cultivation, respectively. These results present a solution to reverse prior loss of SOC by replacing CT dryland agriculture with irrigated NT plus high input cover crops agroecosystems.

7.
J Nat Prod ; 83(4): 1043-1050, 2020 04 24.
Article in English | MEDLINE | ID: mdl-32227943

ABSTRACT

An extract of Galtonia regalis from the Natural Products Discovery Institute showed moderate antiplasmodial activity, with an IC50 value less than 1.25 µg/mL. The two known cholestane glycosides 1 and 2 and the five new cholestane glycosides galtonosides A-E (3-7) were isolated after bioassay-directed fractionation. The structures of the new compounds were determined by interpretation of their NMR and mass spectra. Among these compounds, galtonoside B (4) displayed the most potent antiplasmodial activity, with an IC50 value of 0.214 µM against the drug-resistant Dd2 strain of Plasmodium falciparum.


Subject(s)
Antimalarials/chemistry , Cholestanes/pharmacology , Glycosides/pharmacology , Asparagales/chemistry , Cholestanes/chemistry , Cholestanes/isolation & purification , Glycosides/chemistry , Glycosides/isolation & purification , Humans , Plant Extracts/chemistry , Plant Extracts/isolation & purification , Plasmodium falciparum/chemistry
8.
J Nat Prod ; 83(3): 569-577, 2020 03 27.
Article in English | MEDLINE | ID: mdl-31577436

ABSTRACT

In our continuing search for novel natural products with antiplasmodial activity, an extract of Aniba citrifolia was found to have good activity, with an IC50 value less than 1.25 µg/mL. After bioassay-directed fractionation, the known indolizinium alkaloid anibamine (1) and the new indolizinium alkaloid anibamine B (2) were isolated as the major bioactive constituents, with antiplasmodial IC50 values of 0.170 and 0.244 µM against the drug-resistant Dd2 strain of Plasmodium falciparum. The new coumarin anibomarin A (3), the new norneolignan anibignan A (5), and six known neolignans (7-12) were also obtained. The structures of all the isolated compounds were determined based on analyses of 1D and 2D NMR spectroscopic and mass spectrometric data, and the absolute configuration of anibignan A (5) was assigned from its ECD spectrum. Evaluation of a library of 28 anibamine analogues (13-40) indicated that quaternary charged analogues had IC50 values as low as 58 nM, while uncharged analogues were inactive or significantly less active. Assessment of the potential effects of anibamine and its analogues on the intraerythrocytic stages and morphological development of P. falciparum revealed substantial activity against ring stages for compounds with two C-10 side chains, while those with only one C-10 side chain exhibited substantial activity against trophozoite stages, suggesting different mechanisms of action.


Subject(s)
Alkaloids/pharmacology , Antimalarials/pharmacology , Lauraceae/chemistry , Plasmodium falciparum/drug effects , Pyridines/pharmacology , Cell Line, Tumor , Guyana , Humans , Molecular Structure , Phytochemicals/pharmacology
9.
Bioorg Med Chem Lett ; 28(20): 3368-3371, 2018 11 01.
Article in English | MEDLINE | ID: mdl-30219526

ABSTRACT

Bioassay-guided fractionation of an extract of Carpha glomerata (Cyperaceae) led to the isolation of seven compounds. Compounds 1 (carphorin A), 3 (carphorin C), 4 (carphorin D), and 5 (carphabene) are new compounds, and compound 2 (8-(3″-hydroxyisoamyl)-naringenin) was isolated for the first time as a natural product. All structures were elucidated based on analyses of their HR-ESIMS and 1D and 2D NMR data. Compounds 1, 2, and 6, which have prenyl or hydroxyprenyl side chains, exhibited antiplasmodial activities with IC50 values of 5.2 ±â€¯0.6, 3.4 ±â€¯0.4, and 6.7 ±â€¯0.8 µM against the drug-resistant Dd2 strain of Plasmodium falciparum. In addition the prenylated stilbene 5 also showed good activity, with IC50 5.8 ±â€¯0.7 µM.


Subject(s)
Antimalarials/pharmacology , Cyperaceae/chemistry , Flavanones/pharmacology , Stilbenes/pharmacology , Antimalarials/chemistry , Antimalarials/isolation & purification , Flavanones/chemistry , Flavanones/isolation & purification , Plasmodium falciparum/drug effects , Stilbenes/chemistry , Stilbenes/isolation & purification
10.
J Nat Prod ; 81(5): 1260-1265, 2018 05 25.
Article in English | MEDLINE | ID: mdl-29738243

ABSTRACT

An extract of Petradoria pumila from the Natural Products Discovery Institute was found to have moderate antiplasmodial activity, with an IC50 value between 5 and 10 µg/mL. The four new diterpenoids petradoriolides A-D (1-4), the new benzotropolone petradoriolone (5), and the two known lignans 6 and 7 were isolated after bioassay-directed fractionation. The structures and stereochemistries of the new compounds were determined by interpretation of NMR spectroscopy, mass spectrometry, and ECD spectra. Among these compounds, petradoriolide C (3) displayed the most potent antiplasmodial activity, with an IC50 value of 7.3 µM.


Subject(s)
Antimalarials/chemistry , Asteraceae/chemistry , Biflavonoids/chemistry , Catechin/analogs & derivatives , Diterpenes/chemistry , Antimalarials/pharmacology , Biflavonoids/pharmacology , Catechin/chemistry , Catechin/pharmacology , Diterpenes/pharmacology , Lignans/chemistry , Lignans/pharmacology , Magnetic Resonance Spectroscopy/methods , Plant Extracts/chemistry , Plant Extracts/pharmacology , Plasmodium falciparum/drug effects
11.
J Nat Prod ; 81(3): 475-483, 2018 03 23.
Article in English | MEDLINE | ID: mdl-29048892

ABSTRACT

Nine new compounds containing either a chromane or chromene ring moiety were isolated from the monotypic plant Koeberlinia spinosa. Compounds 1-4 are chromanes with all possible E and Z isomers of the isoprenoid side chain, with compound 5 a methylated derivative of 1. Compounds 6 and 7 were assigned as diastereomeric cyclized derivatives of 2 and were probably artifacts formed during the extraction or the isolation processes. Compounds 8 and 9 were characterized as new chromenes. Structure elucidation of 1-9 was conducted via 1D and 2D NMR spectroscopic data interpretation, and absolute configurations were determined by ECD spectroscopic analysis. Compounds 2, 5, 6, and 7 had weak antiplasmodial activity, while none of the compounds exhibited antiproliferative activity. The isolation, structure elucidation, and biological evaluation of these compounds are presented.


Subject(s)
Antimalarials/pharmacology , Benzopyrans/pharmacology , Magnoliopsida/chemistry , Plasmodium falciparum/drug effects , Animals , Cell Line, Tumor , Cell Proliferation/drug effects , Magnetic Resonance Spectroscopy/methods
12.
Bioorg Med Chem Lett ; 28(1): 40-42, 2018 01 01.
Article in English | MEDLINE | ID: mdl-29162457

ABSTRACT

A bioassay-guided fractionation and chemical investigation of Amaryllis belladonna Steud. bulbs resulted in the isolation and identification of the new crinane alkaloid 1,4-dihydroxy-3-methoxy powellan (1), along with the 3 known crinane alkaloids 2-4 and the two lycorane alkaloids 5-6. The structures were elucidated by interpretation of combined HR-ESIMS, CD and 2D NMR spectroscopic data. Among these isolated compounds the lycorane-type alkaloid acetylcaranine (5) exhibited strong antiplasmodial activity, while compounds 3 and 4 were moderately active, and compounds 1 and 6 were inactive.


Subject(s)
Alkaloids/chemistry , Amaryllidaceae Alkaloids/chemistry , Antimalarials/chemistry , Asparagales/chemistry , Alkaloids/isolation & purification , Alkaloids/pharmacology , Amaryllidaceae Alkaloids/isolation & purification , Amaryllidaceae Alkaloids/pharmacology , Antimalarials/isolation & purification , Antimalarials/pharmacology , Asparagales/metabolism , Cell Line, Tumor , Cell Proliferation/drug effects , Circular Dichroism , Humans , Magnetic Resonance Spectroscopy , Molecular Conformation , Plant Extracts/chemistry , Plant Roots/chemistry , Plant Roots/metabolism , Plasmodium falciparum/drug effects , Spectrometry, Mass, Electrospray Ionization
13.
Chem Biodivers ; 14(9)2017 Sep.
Article in English | MEDLINE | ID: mdl-28621040

ABSTRACT

Bioassay-guided fractionation of a methanol extract of Magnolia grandiflora against Plasmodium falciparum yielded two new (1 and 2) and six known (3 - 8) bioactive compounds. The structures of the new compounds were assigned by mass spectrometric and 1D- and 2D-NMR data. Known compounds were identified by comparison of 1 H-NMR and MS data with literature data. The two known neolignans 3 and 4 showed moderate antiplasmodial activity with the IC50 values of 2.8 ± 0.1 and 3.4 ± 0.1 µm, respectively. Weak antiplasmodial activity was recorded for compounds 1, 2, 5, 6, 7, and 8, with the IC50 values of 38 ± 2, 23 ± 2, 16.5 ± 0.2, 86 ± 1, 44 ± 4, and 114 ± 9 µm, respectively.


Subject(s)
Antimalarials/chemistry , Antimalarials/pharmacology , Lignans/chemistry , Lignans/pharmacology , Magnolia/chemistry , Plasmodium falciparum/drug effects , Antimalarials/isolation & purification , Humans , Lignans/isolation & purification , Malaria, Falciparum/drug therapy , Plant Extracts/chemistry , Plant Extracts/isolation & purification , Plant Extracts/pharmacology
14.
J Nat Prod ; 80(7): 2037-2044, 2017 07 28.
Article in English | MEDLINE | ID: mdl-28654255

ABSTRACT

Bioassay-guided fractionation of a colon cancer growth inhibitory extract of the fungus Paraconiothyrium sp. led to the isolation of eight new versiol derivatives (1, 3-8, 10) along with two known compounds. The structures were elucidated by interpretation of combined MS and 2D NMR spectroscopic data. Compounds 8, 9, and 10 showed cell growth inhibition against COLO205 and KM12 cells, and both 8 and 9 displayed selectivity in their inhibition of melanoma cell lines in the NCI 60 one-dose test. In addition, compound 8 and the crude Paraconiothyrium sp. extract showed potent dose-dependent inhibitory effects in the five-dose NCI 60 cell line assay.


Subject(s)
Ascomycota/chemistry , Colonic Neoplasms/drug therapy , Heterocyclic Compounds, 3-Ring/pharmacology , Naphthalenes/pharmacology , Algorithms , Cell Line, Tumor , Heterocyclic Compounds, 3-Ring/chemistry , Humans , Melanoma , Molecular Structure , Naphthalenes/chemistry , Nuclear Magnetic Resonance, Biomolecular
15.
J Nat Prod ; 80(5): 1639-1647, 2017 05 26.
Article in English | MEDLINE | ID: mdl-28463001

ABSTRACT

A dichloromethane extract of Trichospira verticillata from the Natural Products Discovery Institute was discovered to have good antiplasmodial activity (IC50 ∼5 µg/mL). After purification by liquid-liquid partition and C18 reversed-phase HPLC, four new germacranolide-type sesquiterpenoid lactones named trichospirolides A-D (1-4) were isolated. The structures of the new compounds were elucidated by analysis of their 1D and 2D NMR and MS data. The relative and absolute configurations were assigned based on a comparison of calculated and experimental ECD and UV spectra, specific rotations, internuclear distances, and coupling constants for all possible diastereomers for each compound. Among these four compounds, the conjugated dienone 1 displayed the most potent antiplasmodial activity, with an IC50 value of 1.5 µM.


Subject(s)
Antimalarials/isolation & purification , Antimalarials/pharmacology , Lactones/isolation & purification , Plasmodium falciparum/chemistry , Sesquiterpenes/isolation & purification , Sesquiterpenes/pharmacology , Antimalarials/chemistry , Chromatography, High Pressure Liquid , Inhibitory Concentration 50 , Lactones/chemistry , Lactones/pharmacology , Magnetic Resonance Spectroscopy , Molecular Structure , Sesquiterpenes/chemistry , Stereoisomerism
17.
Bioorg Med Chem ; 24(21): 5418-5422, 2016 11 01.
Article in English | MEDLINE | ID: mdl-27624525

ABSTRACT

Antimalarial bioassay-guided fractionation of the swamp lily Crinum erubescens led to the isolation of four compounds with potent antiplasmodial activity. Compounds 1 and 2 were determined from their spectroscopic data to be the known pesticidal compound cripowellin A and the known pesticidal and antiproliferative compound cripowellin B. 1D and 2D-NMR techniques were used to determine the identities of 3 and 4 as the new compounds cripowellin C and D. A fifth compound was identified as the known alkaloid hippadine, which was inactive against Plasmodium falciparum. The antiplasmodial IC50 values of compounds 1-4 were determined to be 30±2, 180±20, 26±2, and 260±20nM, respectively, and their antiproliferative IC50 values against the A2780 human ovarian cancer cell line were 11.1±0.4, 16.4±0.1, 25±2, and 28±1nM.


Subject(s)
Alkaloids/pharmacology , Antimalarials/pharmacology , Crinum/chemistry , Plasmodium falciparum/drug effects , Alkaloids/chemistry , Alkaloids/isolation & purification , Antimalarials/chemistry , Antimalarials/isolation & purification , Cell Line, Tumor , Cell Proliferation/drug effects , Dose-Response Relationship, Drug , Drug Screening Assays, Antitumor , Humans , Molecular Structure , Parasitic Sensitivity Tests , Structure-Activity Relationship
18.
Nat Prod Commun ; 11(6): 719-21, 2016 Jun.
Article in English | MEDLINE | ID: mdl-27534100

ABSTRACT

Bioassay guided fractionation of the MeOH extract of the plant Gutierrezia sarothrae (Asteraceae) using an assay for antiplasmodial activity against the drug-resistant Dd2 strain of Plasmodium falciparum led to the isolation of the two new diterpenes 3α-angeloyloxy-15-hydroxylabda-7,13-dien-16,15-olid-18-oic acid (1) and 3α-angeloyloxy-15-methoxylabda-7,13-dien-16,15-olid-18-oic acid (2). The structures of 1 and 2 were elucidated by interpretation of 1D and 2D NMR spectroscopic data, mass spectrometry, and comparison with the data of related compounds reported in the literature. Compound 1 exhibited moderate antiplasmodial activity with an IC50 values of 10.4 ± 4.3 µM.


Subject(s)
Antiprotozoal Agents/pharmacology , Asteraceae/chemistry , Diterpenes/pharmacology , Plant Extracts/pharmacology , Plasmodium falciparum/drug effects , Antiprotozoal Agents/chemistry , Antiprotozoal Agents/isolation & purification , Diterpenes/chemistry , Diterpenes/isolation & purification , Molecular Structure , Plant Extracts/chemistry , Plant Extracts/isolation & purification , Plasmodium falciparum/growth & development
19.
Bioorg Med Chem ; 24(11): 2544-8, 2016 06 01.
Article in English | MEDLINE | ID: mdl-27112454

ABSTRACT

Bioassay guided fractionation of a MeOH extract of the stem bark of Syncarpia glomulifera (Myrtaceae) led to the isolation of the two new phloroglucinol derivatives (±)-rhodomyrtosone F (1) and (±)-calliviminone I (2), the three known triterpenes, betulinic acid (3), ursolic acid-3-acetate (4), and ursolic acid (5), and 1-(2,4,6-trihydroxyphenyl)-1-hexanone (6). Compound 1 exhibited strong antiplasmodial activity, while compounds 2-4 were moderately active and 5 and 6 were inactive in this assay. The structures of 1 and 2 were elucidated based on analyses of their mass spectrometric data, 1D and 2D NMR spectra, and comparison with related compounds.


Subject(s)
Antimalarials/pharmacology , Malaria/drug therapy , Myrtaceae/chemistry , Phloroglucinol/pharmacology , Plasmodium falciparum/drug effects , Antimalarials/chemistry , Antimalarials/isolation & purification , Cell Survival/drug effects , Dose-Response Relationship, Drug , HEK293 Cells , Humans , Molecular Structure , Parasitic Sensitivity Tests , Phloroglucinol/chemistry , Phloroglucinol/isolation & purification , Plant Bark/chemistry , Plasmodium falciparum/growth & development , Structure-Activity Relationship
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