RESUMO
Two new macrolides, iriomoteolides-14a (1) and 14b (2) have been isolated from the marine dinoflagellate Amphidinium species (strain KCA09057). Compounds 1 and 2 are 15-membered macrolides, which are structural analogs of amphidinolides O (3) and P (4). The structures of 1 and 2 were assigned on the basis of detailed NMR analyses and chemical conversion studies. Compounds 1 and 2 showed moderate cytotoxic activity against human cervix adenocarcinoma HeLa cells.
Assuntos
Dinoflagellida/química , Macrolídeos/química , Dinoflagellida/classificação , Estrutura MolecularRESUMO
Amphirionin-2 is a linear polyketide metabolite that exhibits potent and selective cytotoxic activity against certain human cancer cell lines. We disclose herein the first total synthesis of amphirionin-2 and determination of its absolute configuration. Our synthesis featured an extensive use of cobalt-catalyzed Mukaiyama-type cyclization of γ-hydroxy olefins for stereoselective formation of all the tetrahydrofuran rings found in the natural product, and a late-stage Stille-type coupling for convergent assembly of the entire carbon backbone. Four candidate diastereomers of amphirionin-2 were synthesized in a unified, convergent manner, and their spectroscopic/chromatographic properties were compared with those of the authentic material. The present study culminated in the reassignment of the C5/C7 relative configuration, assignment of the C12/C18 relative configuration, and determination of the absolute configuration of amphirionin-2.
RESUMO
Viral safety is a critical concern with regard to monoclonal antibody (mAb) products produced in mammalian cells such as Chinese hamster ovary cells. Manufacturers are required to ensure the safety of such products by validating the clearance of viruses in downstream purification steps. Cation exchange (CEX) chromatography is widely used in bind/elute mode as a polishing step in mAb purification. However, bind/elute modes require a large volume of expensive resin. To reduce the production cost, the use of CEX chromatography in overloaded mode has recently been investigated. The viral clearance ability in overloaded mode was evaluated using murine leukemia virus (MLV). Even under high-load conditions such as 2,000 g mAb/L resin, MLV was removed from mAb solutions. This viral clearance ability was not significantly affected by resin type or mAb type. The overloaded mode can also remove other types of viruses such as pseudorabies virus and reovirus Type 3 from mAb solutions. Based on these results, this cost-effective overloaded mode is comparable to the bind-elute mode in terms of viral removal.
Assuntos
Anticorpos Monoclonais , Cromatografia por Troca Iônica/métodos , Vírus/isolamento & purificação , Animais , Anticorpos Monoclonais/análise , Anticorpos Monoclonais/metabolismo , Biotecnologia/métodos , Células CHO , Cátions/química , Cricetinae , CricetulusRESUMO
Iriomoteolide-2a is a marine macrolide metabolite isolated from a cultured broth of the benthic dinoflagellate Amphidinium sp. HYA024 strain. This naturally occurring substance was reported to show remarkable cytotoxic activity against human cancer cell lines HeLa and DG-75 and in vivo antitumor activity against murine leukemia P388 cell line. Herein, the total synthesis, stereochemical revision, and biological assessment of iriomoteolide-2a are reported in detail. Total synthesis of the proposed structure 1 of iriomoteolide-2a featured a late-stage convergent assembly of three components by a Suzuki-Miyaura coupling, an esterification, and a ring-closing metathesis. However, the NMR data of synthetic 1 were not identical to those of the natural product. Careful analysis of the NMR data of the authentic material and synthesis/NMR analysis of appropriately designed model compounds led to consideration of four possible stereoisomers 2-5 as candidates for the correct structure. Accordingly, total syntheses of 2-5 were achieved by taking advantage of the convergent strategy, and comparison of the NMR spectra of synthetic 2-5 with those of the natural product led to the conclusion that 5 shows the correct relative configuration of iriomoteolide-2a. The absolute configuration of this natural product was finally established through chiral HPLC analysis of synthetic 5/ent-5 with the authentic sample. The antiproliferative activity of the synthetic compounds was assessed against HeLa and A549 cells to show that, in contrast to expectation, synthetic 5 and ent-5 were only marginally active in these cell lines. This work clearly underscores the vital role of total synthesis in the establishment of the structure and biological activity of natural products.
Assuntos
Produtos Biológicos/síntese química , Macrolídeos/química , Produtos Biológicos/química , Produtos Biológicos/toxicidade , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Dinoflagellida/química , Dinoflagellida/metabolismo , Esterificação , Humanos , Macrolídeos/síntese química , Macrolídeos/toxicidade , Espectroscopia de Ressonância Magnética , Conformação Molecular , EstereoisomerismoRESUMO
Iriomoteolides-9a (1) and 11a (2), new 15- and 19-membered macrolides, respectively, have been isolated from the marine dinoflagellate Amphidinium species (strain KCA09052). Compounds 1 and 2 were obtained from the extracts of the algal cells inoculated in the PES and TKF seawater medium, respectively. The structures of 1 and 2 were assigned on the basis of detailed NMR analyses. Compounds 1 and 2 exhibited cytotoxic activity against human cervix adenocarcinoma HeLa cells.
Assuntos
Produtos Biológicos/isolamento & purificação , Dinoflagellida/química , Macrolídeos/isolamento & purificação , Adenocarcinoma/tratamento farmacológico , Animais , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Produtos Biológicos/química , Produtos Biológicos/farmacologia , Feminino , Células HeLa , Humanos , Macrolídeos/química , Macrolídeos/farmacologia , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Neoplasias do Colo do Útero/tratamento farmacológicoRESUMO
Two new macrolides, iriomoteolides-10a (1) and -12a (2), have been isolated from a marine dinoflagellate Amphidinium sp. (KCA09053 strain), and their structures were elucidated on the basis of a detailed two dimensional (2D)-NMR analysis. Compound 1 is a novel 21-membered Amphidinium macrolide, which contains one tetrahydrofuran ring, two ketone carbonyls, two hydroxyl groups, and six one-carbon branches. Compound 2 is a new 12-membered macrolide related to amphidinolide Q. Compound 1 exhibited cytotoxic activity against human cervix adenocarcinoma HeLa and murine hepatocellular carcinoma MH134 cells.
Assuntos
Dinoflagellida/química , Macrolídeos/farmacologia , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Células HeLa , Humanos , Macrolídeos/química , Macrolídeos/isolamento & purificação , Camundongos , Conformação Molecular , Relação Estrutura-AtividadeRESUMO
A novel linear polyketide, amphirionin-2 (1), with two unique hexahydrofuro[3,2-b]furan moieties has been isolated from the cultivated algal cells of a benthic dinoflagellate Amphidinium sp. (strain KCA09051). The structure was elucidated on the basis of detailed analyses of 2D NMR data, and the absolute configuration of C-5 was determined by using modified Mosher's method. Amphirionin-2 (1) exhibited potent cytotoxic activity against human colon carcinoma Caco-2 cells and human lung adenocarcinoma A549 cells.
Assuntos
Dinoflagellida/química , Furanos/química , Policetídeos/química , Actinas/antagonistas & inibidores , Actinas/metabolismo , Células CACO-2 , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Dinoflagellida/metabolismo , Furanos/isolamento & purificação , Furanos/toxicidade , Humanos , Espectroscopia de Ressonância Magnética , Conformação Molecular , Policetídeos/isolamento & purificação , Policetídeos/toxicidade , EstereoisomerismoRESUMO
A linear polyketide, amphirionin-4 (1), has been isolated from cultivated algal cells of the marine dinoflagellate Amphidinium species. The structure was elucidated on the basis of detailed analyses of 1D and 2D NMR data, and the absolute configurations of C-4 and C-8 were determined using the modified Mosher's method. Amphirionin-4 (1) exhibited extremely potent proliferation-promoting activity on murine bone marrow stromal ST-2 cells (950% promotion) at a concentration of 0.1 ng/mL.
Assuntos
Dinoflagellida/química , Células-Tronco Mesenquimais/efeitos dos fármacos , Policetídeos/isolamento & purificação , Policetídeos/farmacologia , Animais , Proliferação de Células/efeitos dos fármacos , Macrolídeos/química , Biologia Marinha , Camundongos , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Policetídeos/químicaRESUMO
Hyperpolarization of stable isotope-labeled substrates and subsequent NMR measurement of the metabolic reactions allow for direct tracking of cellular reactions in vitro and in vivo. Here, we report the hyperpolarization of (13)C6-glucose-d7 and evaluate its use as probes to observe glucose flux in cells. We measured the lifetime of the polarized signal governed by the spin-lattice relaxation time T1. (13)C6-Glucose-d7 exhibited a T1 that was over ten times as long as that of (13)C6-glucose, and metabolic NMR studies of hyperpolarized (13)C6-glucose-d7 using tumor cell lysate led to observation of the resonances due to phosphorylated fluctofuranoses generated through aerobic glycolysis.
Assuntos
Glucose/metabolismo , Isótopos de Carbono , Linhagem Celular Tumoral , Glicólise , Humanos , Espectroscopia de Ressonância MagnéticaRESUMO
OBJECTIVES: This study aimed at determining the additional value of FDG PET/CT to contrast-enhanced CT in the differentiation between benign and malignant intraductal papillary mucinous neoplasms (IPMNs) of the pancreas with mural nodules. METHODS: This retrospective review of medical records was approved by our institutional review board. The preoperative PET/CT images of 16 non-diabetic patients with surgically proven IPMN, where mural nodules of 3 mm or larger were shown by preoperative contrast-enhanced CT, were retrospectively evaluated. The 16 patients were divided into two groups: 7 patients with benign IPMN [adenoma (n = 1) and borderline tumor (n = 6)] and 9 patients with malignant IPMN [carcinoma in situ (CIS) (n = 8) and invasive carcinoma (n = 1)]. Nuclear medicine physician blinded to the pathologic assessment of malignancy of IPMN set a spherical volume of interest (VOI) over the mural nodules on PET/CT images and recorded the peak standardized uptake value (SUV(max)) in the VOI, referring the contrast-enhanced CT images. Statistical differences in the size of mural nodule, the diameter of main pancreatic duct (MPD), and SUV(max) of the tumors between benign IPMNs and malignant IPMNs were compared using the Mann-Whitney U test. Statistical significance was set at p < 0.05. Additionally, the diagnostic accuracy of FDG PET for the detection of malignancy was calculated. RESULTS: The SUV(max) of the malignant IPMNs with mural nodules of 3 mm or larger was higher than that of benign IPMNs (2.7 ± 0.6 vs. 1.9 ± 0.3, p < 0.01). Meanwhile, there was no significant difference in mural nodule diameter and MPD diameter between the two groups. FDG PET/CT showed an excellent diagnostic accuracy for the differentiation between malignant and benign IPMNs with mural nodules: the sensitivity, specificity, PPV, NPV, and accuracy in malignant IPMN with mural nodule of FDG PET/CT were 77.8, 100, 100, 77.8, and 87.5 for the cutoff value of 2.3; and 100, 57.1, 75.0, 100, and 81.3 for the cutoff value of 2.0, respectively. CONCLUSIONS: The result of this study indicates that FDG PET/CT can provide additional information for the differentiation between benign and malignant IPMNs of the pancreas with mural nodules.
Assuntos
Adenocarcinoma Mucinoso/diagnóstico , Carcinoma Ductal Pancreático/diagnóstico , Carcinoma Papilar/diagnóstico , Meios de Contraste , Fluordesoxiglucose F18 , Imagem Multimodal , Tomografia por Emissão de Pósitrons , Tomografia Computadorizada por Raios X , Adenocarcinoma Mucinoso/diagnóstico por imagem , Carcinoma Ductal Pancreático/diagnóstico por imagem , Carcinoma Papilar/diagnóstico por imagem , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos RetrospectivosRESUMO
Two novel alkaloids with a furo[2,3-b]pyrazin-2(1H)-one moiety and a guanidino group, hyrtioseragamines A (1) and B (2), have been isolated from an Okinawan marine sponge Hyrtios species. The structures of 1 and 2 were elucidated on the basis of spectroscopic data and chemical conversions. Compounds 1 and 2 are the first natural products possessing a furo[2,3-b]pyrazine-related moiety.
Assuntos
Antifúngicos/isolamento & purificação , Antineoplásicos/isolamento & purificação , Produtos Biológicos/isolamento & purificação , Furanos/isolamento & purificação , Poríferos/química , Pirazinas/isolamento & purificação , Alcaloides/química , Animais , Antifúngicos/química , Antifúngicos/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Aspergillus niger/efeitos dos fármacos , Produtos Biológicos/química , Produtos Biológicos/farmacologia , Cryptococcus neoformans/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Furanos/química , Furanos/farmacologia , Humanos , Células KB , Biologia Marinha , Camundongos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Pirazinas/química , Pirazinas/farmacologiaRESUMO
Mucin-producing intraductal papillary neoplasm (adenocarcinoma/adenoma) in the bile duct is becoming recognized as a specific type of neoplasm. Since, it bears a striking similarity to intraductal papillary mucinous neoplasms of the pancreas with regard to its histopathologic features, the term "intraductal papillary mucinous neoplasms of the bile duct" (IPMN-B) is frequently used, although no definite terminology or definition has been decided by World Health Organization. This neoplasm lacks ovarian-like stroma and communicates with the bile ducts, unlike biliary mucinous cystic neoplasm (MCN). On the other hand, malignant IPMN-B is categorized as an intraductal-growth type of intrahepatic cholangiocarcinoma (ICC). In comparison to other types of ICC, such as the mass-forming type and periductal-infiltrating type that have poor resectability and an unfavorable prognosis, malignant IPMN-B can be resected and demonstrates a more favorable prognosis. Meanwhile, unlike biliary MCN that is usually confined in a closed cyst, IPMN-B can spread along the mucosal surface of the bile ducts, and it should be widely resected. Therefore, multimodality assessment is needed to ensure the correct diagnosis of IPMN-B. We herein review the imaging findings of IPMN-B with pathologic correlation.
Assuntos
Adenocarcinoma Mucinoso/diagnóstico , Adenocarcinoma Papilar/diagnóstico , Neoplasias dos Ductos Biliares/diagnóstico , Ductos Biliares Intra-Hepáticos/patologia , Colangiocarcinoma/diagnóstico , Diagnóstico por Imagem , Neoplasias Hepáticas/diagnóstico , Adenocarcinoma Mucinoso/classificação , Adenocarcinoma Mucinoso/patologia , Adenocarcinoma Papilar/classificação , Adenocarcinoma Papilar/patologia , Neoplasias dos Ductos Biliares/classificação , Neoplasias dos Ductos Biliares/patologia , Colangiocarcinoma/classificação , Colangiocarcinoma/patologia , Meios de Contraste , Diagnóstico Diferencial , Humanos , Neoplasias Hepáticas/classificação , Neoplasias Hepáticas/patologiaRESUMO
Accurate diagnosis of local invasion of hilar cholangiocarcinomas is challenging due to their small size and the anatomic complexity of the hepatic hilar region. On the other hand, the correct diagnosis of local invasion is essential for assuring the possibility of curative surgery. The purpose of this study was to evaluate the feasibility of four-channel multidetector-row computed tomography (MDCT) in the assessment of vascular and bile duct involvement, by which we could obtain useful information for the surgical management of hilar cholangiocarcinoma. The subjects were 18 patients for whom the extent of tumor invasion was surgically and pathologically confirmed. All patients underwent preoperative multiphasic CT scanning by MDCT. Arterial and portal dominant phases were acquired using a detector configuration of 1.25 mm X 4 mm, and both axial and multiplanar reconstructed images were interpreted. Longitudinal extension was evaluated up to second-order branches. Vascular invasion is considered to be the degree of tumor contiguity to the hepatic arteries and portal vein and was graded by CT. The longitudinal extension was correctly diagnosed in 14 patients (77.8%). Hepatic artery invasion was correctly diagnosed in 17 patients with sensitivity of 100% and specificity of 90%, respectively. Portal vein invasion was correctly diagnosed in 47 of 51 branches with sensitivity and specificity of 92.3% and 90.2%, respectively. Multiplanar reconstructed images contributed to the correct diagnosis for both vascular encasement and longitudinal tumor extension. In conclusion, MDCT is useful in preoperative evaluation of hilar cholangiocarcinoma, especially when combined with multiplanar reconstructed images.
Assuntos
Colangiocarcinoma/irrigação sanguínea , Colangiocarcinoma/diagnóstico , Tomografia Computadorizada por Raios X/métodos , Idoso , Idoso de 80 Anos ou mais , Colangiocarcinoma/classificação , Colangiocarcinoma/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sensibilidade e EspecificidadeRESUMO
A 15-membered macrolide, iriomoteolide-3a (1), with an allyl epoxide has been isolated from a marine benthic dinoflagellate Amphidinium sp. (strain HYA024), and the structure was assigned by detailed analyses of 2D NMR data. Relative and absolute configurations were elucidated on the basis of conformational studies of 1 and its acetonide (2) and modified Mosher's method of 1, respectively. Iriomoteolide-3a (1) and the acetonide (2) exhibited potently cytotoxic activity against antitumor cells.
Assuntos
Dinoflagellida/química , Macrolídeos/isolamento & purificação , Animais , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Macrolídeos/química , Espectroscopia de Ressonância Magnética , Modelos MolecularesRESUMO
A new cytotoxic bis-indole alkaloid, hyrtinadine A (1), with a pyrimidine moiety has been isolated from an Okinawan marine sponge Hyrtios sp., and the structure was elucidated on the basis of spectroscopic data.
Assuntos
Antineoplásicos/isolamento & purificação , Alcaloides Indólicos/isolamento & purificação , Poríferos/química , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Alcaloides Indólicos/química , Alcaloides Indólicos/farmacologia , Concentração Inibidora 50 , Células KB , Biologia Marinha , Estrutura MolecularRESUMO
PURPOSE: To evaluate the effectiveness and safety of ipsilateral percutaneous transhepatic portal vein embolization (PTPVE) with gelatin sponge particles and coils to induce lobar hypertrophy in patients with hilar cholangiocarcinoma in preparation for extended right hepatectomy. MATERIALS AND METHODS: Between 1999 and 2004, PTPVE was performed in 22 patients with hilar cholangiocarcinoma (mean age, 67 years; range, 57-77 y; 16 men and six women). Percutaneous puncture of the right portal vein was performed under ultrasound guidance. A reverse-curve catheter was used for right portal vein embolization. Coils were used to occlude second-order branches. The future liver remnant volume was assessed by comparing computed tomographic scans before and 14-24 days after PTPVE. RESULTS: PTPVE was technically successful in all cases. The average increase in ratio of future liver remnant volume to total liver volume was 8.6%. Liver function tests after PTPVE but before surgery showed no significant changes. Nineteen patients underwent hepatic resection without liver failure. In three patients, tumors could not be removed because of detection of extrahepatic disease. One patient who underwent successful hepatic resection had an abscess in the removed right lobe. CONCLUSION: Ipsilateral PTPVE with gelatin sponge and coils appears to be effective and safe for extended right hepatectomy for hilar cholangiocarcinoma.
Assuntos
Neoplasias dos Ductos Biliares/terapia , Ductos Biliares Intra-Hepáticos , Colangiocarcinoma/terapia , Veia Porta , Idoso , Neoplasias dos Ductos Biliares/diagnóstico por imagem , Neoplasias dos Ductos Biliares/cirurgia , Colangiocarcinoma/diagnóstico por imagem , Colangiocarcinoma/cirurgia , Terapia Combinada , Embolização Terapêutica , Feminino , Esponja de Gelatina Absorvível/uso terapêutico , Hepatectomia , Humanos , Masculino , Pessoa de Meia-Idade , Flebografia , Punções , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Ultrassonografia de IntervençãoRESUMO
The absolute configurations at five chiral centers, except for C-32(S) reported previously, in iejimalides A, C, and D, potent cytotoxic 24-membered macrolides isolated from a tunicate Eudistoma cf. rigida, were assigned as 4R, 9S, 17S, 22S, and 23S on the basis of detailed analysis of NMR data and chemical means. Furthermore, the structures proposed for iejimalides A, C, and D were revised to their 13Z-isomers. Iejimalides A-D (1-4) exhibited antitumor activity in vivo.
Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Macrolídeos/química , Macrolídeos/farmacologia , Animais , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Dicroísmo Circular , Humanos , Espectroscopia de Ressonância Magnética , Camundongos , Estrutura Molecular , Estereoisomerismo , Relação Estrutura-Atividade , Urocordados/química , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
A new polyketide glycoside, cladionol A (1), was isolated from the cultured broth of a fungus Gliocladium sp., which was separated from sea grass Syringodium isoetifolium, and the structure was elucidated by spectroscopic data. The relative stereochemistry of C-2-C-3 was assigned by mainly J-based configuration analysis, while those of two sugar units were elucidated to be beta-mannopyranoside and arabitol on the basis of NOESY data and/or 1H-1H couplings. Furthermore, the absolute configuration of the mannose moiety was determined as the D-form on the basis of chiral HPLC analysis of a benzoyl derivative of the acid hydrolysate of 1. Cladionol A (1) exhibited modest cytotoxicity.
Assuntos
Antineoplásicos/isolamento & purificação , Gliocladium/química , Glicosídeos/isolamento & purificação , Antineoplásicos/química , Antineoplásicos/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Glicosídeos/química , Glicosídeos/farmacologia , Japão , Modelos Moleculares , Estrutura MolecularRESUMO
To determine computed tomographic (CT) imaging characteristics of retropharygeal edema, we reviewed CT images in 18 patients with head and neck tumors. Retropharyngeal edema spread craniocaudally between soft palate and upper half of thyroid cartilage in all patients. No edema fluid extended above soft palate and below thyroid cartilage. Horizontally, it spread symmetrically in ten and asymmetrically in eight patients. Predominance in asymmetrical retropharyngeal edema was found on the same side as that of unilateral predominance both in lymph nodes enlargement and jugular vein stenosis/occlusion. All patients had edema also in other cervical spaces. Edema of retropharyngeal and other spaces fluctuated synchronously. In 14 patients, as primary lesion and/or cervical lymph nodes regressed, retropharyngeal edema disappeared or decreased. Retropharyngeal edema had some imaging characteristics. With knowledge of that, we could avoid diagnostic confusion when evaluating head and neck CT images.
Assuntos
Edema/etiologia , Edema/patologia , Neoplasias de Cabeça e Pescoço/complicações , Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Doenças Faríngeas/diagnóstico por imagem , Doenças Faríngeas/etiologia , Adulto , Idoso , Feminino , Lateralidade Funcional , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Tomografia Computadorizada por Raios XRESUMO
Solution conformations of amphidinolide H (1), a 26-membered macrolide exhibiting potent cytotoxic and antitumor activity, in CDCl3 and DMSO-d6 were investigated on the basis of NMR data, distance geometry calculation, and restrained energy minimization. Three-dimensional conformations in CDCl3 were suggested to be close to the X-ray structure of 1, while those in DMSO-d6 were indicated to be different from both those in CDCl3 and the X-ray structure.