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1.
Jpn J Clin Oncol ; 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38920339

RESUMEN

OBJECTIVES: This study explored the impacts of peri-operative changes in the neutrophil-to-lymphocyte ratio (NLR) on the survival rate after radical nephroureterectomy. METHODS: This retrospective analysis included a multicentric cohort of patients diagnosed with upper tract urothelial carcinoma (UTUC) who had undergone radical nephroureterectomy from 2012 to 2021. We assessed the preoperative NLR, postoperative NLR, delta-NLR (difference between postoperative and preoperative NLRs), and NLR change (ratio of postoperative to preoperative NLR). Additionally, patients were categorized according to increases in their preoperative and/or postoperative NLRs. Associations of survival with peri-operative changes in the NLR were investigated using Cox multivariate regression models. RESULTS: A total of 488 patients were included in the study, with a median age of 73 years. Among the patients, 105 (21.5%) exhibited elevated preoperative and postoperative NLRs, 88 (18.0%) exhibited elevated preoperative NLR only, 53 (10.9%) exhibited elevated postoperative NLR only, and 242 (49.6%) exhibited normal NLRs. Multivariate analysis indicated significant negative correlations between both preoperative and postoperative increased NLRs and oncological outcomes, including nonurothelial tract recurrence-free survival and cancer-specific survival (hazard ratio [HR]: 1.65, P = 0.017; HR: 2.12, P = 0.014, respectively). CONCLUSION: This is the first study to evaluate the association between peri-operative changes in the NLR and the outcomes of patients with UTUC who underwent radical nephroureterectomy. Patients with elevated NLRs at both time points experienced considerably worse outcomes. Further research should explore whether increases in the NLR during long-term follow-up could indicate impending disease recurrence.

2.
Int J Clin Oncol ; 2024 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-38769191

RESUMEN

OBJECTIVE: Phase III clinical trials demonstrated the efficacy of enzalutamide and apalutamide in patients with non-metastatic castration-resistant prostate cancer (nmCRPC) and PSA doubling time ≤10 months. Although these drugs have been shown to vary in their adverse event (AE) profiles, the differences in their efficacy profiles remain to be evaluated. Therefore, this retrospective study was conducted to evaluate the efficacy of these drugs in patients with nmCRPC. METHODS: This study evaluated 191 patients with nmCRPC treated with enzalutamide (n = 137) or apalutamide (n = 54) in the first-line setting at Jikei University Hospital or its affiliated hospitals between May 2014 and November 2022. Endpoints were defined as oncological outcomes (i.e., PSA response, PFS, PSA-PFS, MFS, CSS, and OS) and AEs. RESULTS: No significant differences were noted in patient backgrounds between the two groups. Patients exhibiting a maximum PSA response of >50% and >90% accounted for 74.5% and 48.9% of patients in the enzalutamide group, and 75.9% and 42.6% of patients in the apalutamide group, respectively, with no significant difference between the groups. The median PSA-PFS was 10 months in the enzalutamide group but not in the apalutamide group, with no significant difference between the groups (P = 0.48). No significant differences were observed in MFS, CSS, or OS between the groups. Patients reporting AEs of all grades and grade 3 or higher accounted for 56.2% and 4.3% of those in the enzalutamide group and 57.4% and 7.4% of those in the apalutamide group, respectively. The most common AE was fatigue (26.3%) in the enzalutamide group and skin rash (27.8%) in the apalutamide group. CONCLUSION: In this retrospective study of their efficacy and safety, enzalutamide and apalutamide were shown to exhibit comparable oncological outcomes but quite different AE profiles, suggesting that their differential use may be warranted based on these findings.

3.
Beilstein J Org Chem ; 20: 753-766, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38633912

RESUMEN

Secondary metabolites produced by actinomycete strains undoubtedly have great potential for use in applied research areas such as drug discovery. However, it is becoming difficult to obtain novel compounds because of repeated isolation around the world. Therefore, a new strategy for discovering novel secondary metabolites is needed. Many researchers believe that actinomycetes have as yet unanalyzed secondary metabolic activities, and the associated undiscovered secondary metabolite biosynthesis genes are called "silent" genes. This review outlines several approaches to further activate the metabolic potential of actinomycetes.

4.
Biosci Biotechnol Biochem ; 88(3): 316-321, 2024 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-38086614

RESUMEN

When cultured anaerobically, Enterocloster sp. RD014215 was found to produce 1. Using nuclear magnetic resonance and mass spectroscopy, the planar structure of 1 was determined to be 3-hydroxy-3-(2-oxopropyl)indolin-2-one. The chirality of 1 was implied as S by comparing the optical rotation value of 1 with literature reports of the synthesized compounds. To our knowledge, this work represents the first discovery of the metabolite produced by Enterocloster strain. 1 exhibited inhibition of nitric oxide (NO) production, demonstrating a 50% inhibitory activity (IC50) of 34 µm for NO production by murine macrophage cells subjected to lipopolysaccharide stimulation.


Asunto(s)
Macrófagos , Óxido Nítrico , Humanos , Ratones , Animales , Óxido Nítrico/metabolismo , Óxido Nítrico Sintasa de Tipo II , Macrófagos/metabolismo , Indoles/farmacología , Indoles/metabolismo , Lipopolisacáridos/farmacología
5.
J Antibiot (Tokyo) ; 77(1): 30-38, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37938761

RESUMEN

We screened a library of microbial extracts and compounds library using our constructed assay cells and found pulicatins F (1) and G (2), and cyclopiazonic acid (CPA) (3) as Notch activators. Pulicatin F (1) and (±)-pulicatin G were synthesized and their activities were evaluated. Notch activation of CPA (3) was investigated using Western blot and RT-PCR. CPA (3) increased protein level of HES1 and mRNA expression of HES1. Also, the expression of FMS-like tyrosine kinase 3 (FLT3), which was known to inhibit apoptosis, was also inhibited by CPA (3) addition. The Notch activation by CPA (3) and cytotoxicity against HL-60 were clearly canceled by addition of FK506, which is an inhibitor of calcineurin (CaN). In addition, it was revealed that CPA (3) induced apoptosis in HL-60 cells.


Asunto(s)
Apoptosis , Calcineurina , Humanos , Células HL-60 , Indoles/farmacología
6.
Int J Clin Oncol ; 29(1): 55-63, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37863996

RESUMEN

BACKGROUND: Recent clinical trials have reported improved disease-free survival rates of patients with stage pT3-4/ypT2-4 or pN + upper tract urothelial carcinoma (UTUC) on adjuvant nivolumab therapy. However, the appropriateness of the patient selection criteria used in clinical practice remains uncertain. METHODS: We retrospectively analyzed 895 patients who underwent nephroureterectomy to treat UTUC. The patients were divided into two groups: grade pT3-4 and/or pN + without neoadjuvant chemotherapy (NAC) or grade ypT2-4 and/or ypN + on NAC (adjuvant immunotherapy candidates) and others (not candidates for adjuvant immunotherapy). Kaplan-Meier curves were drawn to assess the oncological outcomes, including recurrence-free survival (RFS), cancer-specific survival (CSS), and overall survival (OS). Cox proportional hazards models were used to identify significant prognostic factors for oncological outcomes. RESULTS: The Kaplan-Meier curves revealed notably inferior RFS, CSS, and OS of patients who were candidates for adjuvant immunotherapy. Multivariate analysis revealed that pathological T and N grade and lymphovascular invasion (LVI) status were independent risk factors for poor RFS, CSS, and OS. CONCLUSION: In total, 44.8% of patients were candidates for adjuvant immunotherapy. In addition to pathological T and N status, LVI was a significant predictor of survival, and may thus play a pivotal role in the selection of patients eligible for adjuvant immunotherapy.


Asunto(s)
Carcinoma de Células Transicionales , Neoplasias de la Vejiga Urinaria , Neoplasias Urológicas , Humanos , Carcinoma de Células Transicionales/tratamiento farmacológico , Carcinoma de Células Transicionales/patología , Neoplasias Urológicas/tratamiento farmacológico , Neoplasias Urológicas/cirugía , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico , Estudios Retrospectivos , Nefroureterectomía/métodos , Pronóstico , Quimioterapia Adyuvante/métodos
7.
J Vet Diagn Invest ; 35(5): 484-491, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37452573

RESUMEN

The fowl glioma-inducing virus prototype (FGVp) and its variants, which belong to avian leukosis virus subgroup A (ALV-A), induce cardiomyocyte abnormalities and gliomas in chickens. However, the molecular mechanisms underlying these myocardial changes remain unclear, and ALV-induced tumorigenesis, which is caused by proviral insertional mutagenesis, does not explain the early development of cardiac changes in infected chickens. We established a quantitative PCR (qPCR) assay to measure ALV-A proviral loads in the brains and hearts of FGV-infected Japanese bantam chickens and compared these results with morphologic lesions. Four of 22 bantams had both gliomas and cardiac lesions. Hearts with cardiac lesions had a higher proviral load (10.3 ± 2.7 proviral copies/nucleus) than those without cardiac lesions (0.4 ± 0.4), suggesting that the proviral load in hearts is correlated with the frequency of myocardial changes. Our qPCR method may be useful in the study of ALV-induced cardiomyocyte abnormalities.


Asunto(s)
Virus de la Leucosis Aviar , Glioma , Enfermedades de las Aves de Corral , Carga Viral , Animales , Virus de la Leucosis Aviar/genética , Pollos , Glioma/patología , Glioma/veterinaria , Enfermedades de las Aves de Corral/virología , Provirus/genética
8.
Int J Mol Sci ; 24(9)2023 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-37175707

RESUMEN

The gel-phase domains in a binary supported lipid bilayer (SLB) comprising dioleoylphosphatidylcholine (DOPC) and dipalmitoylphosphatidylcholine (DPPC) were localized on graphene oxide (GO) deposited on a SiO2/Si substrate. We investigated the distribution of the gel-phase domains and the liquid crystalline (Lα) phase regions in DOPC+DPPC-SLB on thermally oxidized SiO2/Si substrates with GO flakes to understand the mechanism of the domain localization on GO. Fluorescence microscopy and atomic force microscopy revealed that the gel-phase domains preferably distributed on GO flakes, whereas the fraction of the Lα-phase increased on the bare SiO2 surface which was not covered with the GO flakes. The gel-phase domain was condensed on GO more effectively at the lower cooling rate. We propose that nucleation of the gel-phase domain preferentially occurred on GO, whose surface has amphiphilic property, during the gel-phase domain formation. The domains of the liquid ordered (Lo) phase were also condensed on GO in a ternary bilayer containing cholesterol that was phase-separated to the Lo phase and the liquid disordered phase. Rigid domains segregates on GO during their formation process, leaving fluid components to the surrounding region of GO.


Asunto(s)
Grafito , Membrana Dobles de Lípidos , Membrana Dobles de Lípidos/química , Dióxido de Silicio , Fosfatidilcolinas/química , 1,2-Dipalmitoilfosfatidilcolina/química , Microscopía de Fuerza Atómica
9.
Avian Pathol ; 52(4): 264-276, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37194644

RESUMEN

We previously described cardiomyocyte abnormality caused by Km_5666 strain, a variant of fowl glioma-inducing virus (FGV) prototype, which is an avian leukosis virus (ALV). However, the cardiac involvement appeared to be eradicated from the flock after a few years. An epidemiological survey from 2017 to 2020 was performed to elucidate the current prevalence of the cardiopathogenic strains in this flock. Four of the 71 bantams pathologically examined showed both glioma and cardiomyocyte abnormality, from which three ALV strains were detected. DNA sequencing revealed that several different ALV strains coexisted in each bantam and that the conserved Km_5666 virus fluid also contained at least two different ALV strains. We generated three infectious molecular clones from these samples, named KmN_77_clone_A, KmN_77_clone_B, and Km_5666_clone. The envSU of KmN_77_clone_A shared high sequence identity with that of Km_5666 (94.1%). In contrast, the envSU of KmN_77_clone_B showed >99.2% nucleotide similarity with that of an FGV variant without cardiopathogenicity. Furthermore, Km_5666_clone experimentally reproduced both gliomas and cardiomyocyte abnormality in chickens. From these results, it is suggested that the pathogenic determinant of cardiomyocyte abnormality is located in envSU similar to that of Km_5666. The cloning technique described here is beneficial for evaluating the viral pathogenicity in cases where affected birds are coinfected with several different ALV strains.


Asunto(s)
Virus de la Leucosis Aviar , Leucosis Aviar , Glioma , Enfermedades de las Aves de Corral , Animales , Virus de la Leucosis Aviar/genética , Pollos , Glioma/veterinaria , Células Clonales/patología
10.
Artículo en Inglés | MEDLINE | ID: mdl-35786342

RESUMEN

BACKGROUND: Mitochondrial morphology reversibly changes between fission and fusion. As these changes (mitochondrial dynamics) reflect the cellular condition, they are one of the simplest indicators of cell state and predictors of cell fate. However, it is currently difficult to classify them using a simple and objective method. OBJECTIVE: The present study aimed to evaluate mitochondrial morphology using Deep Learning (DL) technique. METHODS: Mitochondrial images stained by MitoTracker were acquired from HeLa and MC3T3-E1 cells using fluorescent microscopy and visually classified into four groups based on fission or fusion. The intra- and inter-rater reliabilities for visual classification were excellent [(ICC(1,3), 0.961 for rater 1; and 0.981 for rater 2) and ICC(1,3), respectively]. The images were divided into test and train images, and a 50-layer ResNet CNN architecture (ResNet-50) using MATLAB software was used to train the images. The datasets were trained five times based on five-fold cross-validation. RESULT: The mean of the overall accuracy for classifying mitochondrial morphology was 0.73±0.10 in HeLa. For the classification of mixed images containing two types of cell lines, the overall accuracy using mixed images of both cell lines for training was higher (0.74±0.01) than that using different cell lines for training. CONCLUSION: We developed a classifier to categorize mitochondrial morphology using DL.


Asunto(s)
Aprendizaje Profundo , Línea Celular , Mitocondrias
11.
J Nat Prod ; 85(11): 2583-2591, 2022 11 25.
Artículo en Inglés | MEDLINE | ID: mdl-36223390

RESUMEN

Dihydromaniwamycin E (1), a new maniwamycin derivative featuring an azoxy moiety, has been isolated from the culture extract of thermotolerant Streptomyces sp. JA74 along with the known analogue maniwamycin E (2). Compound 1 is produced only by cultivation of strain JA74 at 45 °C, and this type of compound has been previously designated a "heat shock metabolite (HSM)" by our research group. Compound 2 is detected as a production-enhanced metabolite at high temperature. Structures of 1 and 2 are elucidated by NMR and MS spectroscopic analyses. The absolute structure of 1 is determined after the total synthesis of four stereoisomers. Though the absolute structure of 2 has been proposed to be the same as the structure of maniwamycin D, the NMR and the optical rotation value of 2 are in agreement with those of maniwamycin E. Therefore, this study proposes a structural revision of maniwamycins D and E. Compounds 1 and 2 show inhibitory activity against the influenza (H1N1) virus infection of MDCK cells, demonstrating IC50 values of 25.7 and 63.2 µM, respectively. Notably, 1 and 2 display antiviral activity against SARS-CoV-2, the causative agent of COVID-19, when used to infect 293TA and VeroE6T cells, with 1 and 2 showing IC50 values (for infection of 293TA cells) of 19.7 and 9.7 µM, respectively. The two compounds do not exhibit cytotoxicity in these cell lines at those IC50 concentrations.


Asunto(s)
Antivirales , Compuestos Azo , COVID-19 , Subtipo H1N1 del Virus de la Influenza A , SARS-CoV-2 , Streptomyces , Humanos , Antivirales/química , Antivirales/metabolismo , Antivirales/farmacología , Compuestos Azo/química , Compuestos Azo/metabolismo , Compuestos Azo/farmacología , Respuesta al Choque Térmico , Células HEK293 , Subtipo H1N1 del Virus de la Influenza A/efectos de los fármacos , Gripe Humana/tratamiento farmacológico , Células de Riñón Canino Madin Darby , Infecciones por Orthomyxoviridae/tratamiento farmacológico , SARS-CoV-2/efectos de los fármacos , Streptomyces/química , Streptomyces/metabolismo , Células Vero , Chlorocebus aethiops , Perros
12.
Water Res X ; 16: 100153, 2022 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-36032788

RESUMEN

Catalytic oxidative removal of Mn2+ on activated-carbon surfaces by free chlorine was recently discovered and found to be potentially practicable for water treatment when using micrometer-sized activated carbon. Herein, we newly derived a kinetic model for trace-substance removal by catalytic reaction and applied it to the Mn2+ removal. External-film mass transfer, adsorption, and oxidation/desorption contributed similarly to the Mn2+ removal rate under actual practical conditions. The low removal rate in natural water was attributed to decreases in available adsorption sites: e.g., a 50% decrease in available sites in water with 0.26 mmol-Ca2+/L caused a 15% reduction in removal rate. Low temperature greatly reduced the removal rate by both enhancing the decrease in available sites and hindering mass transfer through increased viscosity. While adsorption sites differed 8-fold between different carbon particles, causing a 2.2-fold difference in removal rates, carbon particle size was more influential, with a >10-fold difference between 2- and 30-µm sizes.

13.
J Antibiot (Tokyo) ; 75(9): 509-513, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35918479

RESUMEN

The thermotolerant strain Streptomyces sp. HR41 was found to produce compound 1 only in a 45 °C culture, and not at the standard temperature. We previously designated this type of compound as a "heat shock metabolite" (HSM). NMR and MS analytical techniques were used to determine that the chemical structure of 1 comprised a methylated-oxazole ring and a linear chain moiety modified with a terminal amide group. Thus, 1 was shown to be a new curromycin analog, which we have designated noaoxazole (1). Compound 1 weakly activated Notch signal reporter activity without exhibiting cytotoxicity against assay cells at the same concentration.


Asunto(s)
Streptomyces , Termotolerancia , Respuesta al Choque Térmico , Oxazoles/metabolismo , Streptomyces/metabolismo
14.
J Reprod Dev ; 68(5): 330-334, 2022 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-35908958

RESUMEN

Conventional culture systems for bovine embryos are unable to support sustained embryonic development until the developmentally mature blastocyst stage. Although we have previously developed an on-gel culture system that enables bovine blastocysts to complete cell segregation events at day (D) 10 following in vitro culture, the development of D10 blastocysts to term has yet to be achieved. In this study, we attained full-term development of D10 mature blastocysts produced using an on-gel culture system. Two calves derived from on-gel-cultured embryos were vaginally born, showing normal birth and placental weights and no obvious morphological abnormalities. Moreover, we detected no abnormalities in blood metabolic profile analyses. Our findings indicate that on-gel culturing can be used to facilitate the development of developmentally mature blastocysts to term, and produce healthy viable calves. This culture system could make a valuable contribution to cattle production and would enable a range of analyses for characterizing bovine-specific pre-implantation development.


Asunto(s)
Blastocisto , Placenta , Animales , Bovinos , Técnicas de Cultivo de Embriones/veterinaria , Desarrollo Embrionario , Femenino , Fertilización In Vitro/veterinaria , Embarazo
15.
J Nat Prod ; 85(7): 1697-1703, 2022 07 22.
Artículo en Inglés | MEDLINE | ID: mdl-35708315

RESUMEN

Phytohabitols A-C (1-3), new terminally δ-lactonized linear polyketides, were isolated from the culture extract of a rare actinomycete of the genus Phytohabitans. The structures of 1-3, substituted with multiple methyl and hydroxy groups on a conjugated and a skipped diene-containing backbone, were elucidated by NMR and MS spectroscopic analyses. The absolute configuration of 1 was determined by chemical derivatization and chiral anisotropic analysis, coupled with ROESY and J-based configuration analysis. In addition, closely similar 1H and 13C NMR data and optical rotations among 1-3 supported the same stereochemistry of these polyketides. The related streptomycetes metabolites lagunapyrones B, C, and D have α-pyrone rings on the linear part in place of the δ-lactone, but their chirality at the C19-C21 stereocenters were opposite from those described here, posing a question on the previous assignment made solely by comparison of the optical rotations of four possible diastereomers. Compounds 1-3 inhibited migration of cancer cells with IC50 values of 15, 11, and 8.3 µM, respectively, at noncytotoxic concentrations. In addition, 1-3 displayed potent antitrypanosomal activity against Trypanosoma cruzi with IC50 values of 12, 6.4, and 18 µM, comparable to a commonly used therapeutic drug, benznidazole (IC50 16 µM).


Asunto(s)
Actinobacteria , Micromonosporaceae , Policétidos , Imidazoles , Lactonas/farmacología , Estructura Molecular , Policétidos/química , Policétidos/farmacología , Sulfonamidas , Tiofenos
16.
J Antibiot (Tokyo) ; 75(1): 44-47, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34522026

RESUMEN

A rare actinomycetal strain of the genus Actinomycetospora was found to produce a new tryptophan derivative, designated mycetoindole (1). The structure of 1 was determined to be N-3-methylcrotonoyl (Z)-dehydrotryptophan by NMR and MS analytical methods. Compound 1 reduced the root growth of lettuce Lactuca sativa seedlings at concentrations above 0.1 µM and almost completely inhibited seed germination at 10 µM.


Asunto(s)
Actinobacteria/metabolismo , Actinobacteria/química , Animales , Bacterias/efectos de los fármacos , Fermentación , Germinación/efectos de los fármacos , Humanos , Lactuca/efectos de los fármacos , Lactuca/crecimiento & desarrollo , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Pruebas de Sensibilidad Microbiana , Raíces de Plantas/efectos de los fármacos , Raíces de Plantas/crecimiento & desarrollo , Plantones , Triptófano/análogos & derivados , Triptófano/biosíntesis
17.
Jpn J Infect Dis ; 75(2): 156-163, 2022 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-34470969

RESUMEN

Escherichia albertii is an emerging zoonotic foodborne pathogen. Several outbreaks of E. albertii have occurred, particularly in Japan. Although birds have been considered as one of the most important reservoirs of this bacterium, information regarding its prevalence in birds is still scarce. We performed a survey of E. albertii in wild birds in Japan and examined the characteristics of these isolates. E. albertii-specific genes were detected in five cloacal swabs from 156 birds by PCR. Four E. albertii strains were isolated from a swallow with two different E. albertii strains and two pigeons in a flock using XRM-MacConkey agar. These isolates were assigned to biogroup 3, showed no resistance to any tested antimicrobials, and were classified into two EAO-genotypes (EAOg2 and EAOg33) and were untypable. Similar to clinical E. albertii strains, these isolates carried virulence genes, including eae (n = 4), paa (n = 4), Eccdt-I (n = 2), and stx2f (n = 1), as well as Eacdt. Furthermore, stx2f genes in a strain were located on an inducible bacteriophage, which can confer the ability to produce Stx2f in E. coli. In conclusion, Japanese wild birds carried E. albertii at levels similar to the reported prevalence in birds. These isolates may have the potential to cause gastroenteritis in humans.


Asunto(s)
Escherichia coli , Escherichia , Animales , Aves , Medios de Cultivo , Escherichia/genética , Japón/epidemiología
18.
J Nat Med ; 76(1): 234-243, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34779991

RESUMEN

Notch signaling plays crucial roles in cell differentiation and proliferation, but aberrant activation of this signaling results in tumorigenesis and cancer progression. Notch signaling is thus a promising drug target for oncotherapy, and the development of Notch signaling inhibitors is eagerly awaited. Notch inhibitory activity-guided fractionation of a Spilanthes acmella extract led to the identification of five sesquiterpene lactones: tagitinin A (1), 1ß,2α-epoxytagitinin C (2), tagitinin C (3), orizabin (4), and 2α-hydroxytirotundin (5). 1ß,2α-Epoxytagitinin C (2) exhibited Notch signaling inhibition, with an IC50 of 25.6 µM, and was further evaluated for its activity against HPB-ALL, a Notch-activated leukemia cell line. Compound 2 showed potent cytotoxicity against HPB-ALL (IC50 1.7 µM) and arrested the cell cycle at the G2/M phase, but did not induce apoptotic cell death. Notch inhibitory mechanism analysis suggested that compound 2 transcriptionally suppresses Notch1 mRNA. In addition, we found that oxidative stress induction is critical for Notch signaling inhibition and the cytotoxicity of compound 2. This is the first mechanism of small molecule Notch inhibition. Our results demonstrate that 1ß,2α-epoxytagitinin C (2) is a potential anti-leukemia agent and further investigation of this compound is warranted.


Asunto(s)
Leucemia , Apoptosis , Línea Celular Tumoral , Humanos , Leucemia/tratamiento farmacológico , Estrés Oxidativo , Transducción de Señal
19.
Abdom Radiol (NY) ; 47(2): 891-902, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34914007

RESUMEN

PURPOSE: In contrast-enhanced abdominopelvic CT (CE-APCT) for oncologic follow-up, ultrahigh-resolution CT (UHRCT) may improve depiction of fine lesions and low-dose scans are desirable for minimizing the potential adverse effects by ionizing radiation. We compared image quality and radiologists' acceptance of model-based iterative (MBIR) and deep learning (DLR) reconstructions of low-dose CE-APCT by UHRCT. METHODS: Using our high-resolution (matrix size: 1024) and low-dose (tube voltage 100 kV; noise index: 20-40 HU) protocol, we scanned phantoms to compare the modulation transfer function and noise power spectrum between MBIR and DLR and assessed findings in 36 consecutive patients who underwent CE-APCT (noise index: 35 HU; mean CTDIvol: 4.2 ± 1.6 mGy) by UHRCT. We used paired t-test to compare objective noise and contrast-to-noise ratio (CNR) and Wilcoxon signed-rank test to compare radiologists' subjective acceptance regarding noise, image texture and appearance, and diagnostic confidence between MBIR and DLR using our routine protocol (matrix size: 512; tube voltage: 120 kV; noise index: 15 HU) for reference. RESULTS: Phantom studies demonstrated higher spatial resolution and lower low-frequency noise by DLR than MBIR at equal doses. Clinical studies indicated significantly worse objective noise, CNR, and subjective noise by DLR than MBIR, but other subjective characteristics were better (P < 0.001 for all). Compared with the routine protocol, subjective noise was similar or better by DLR, and other subjective characteristics were similar or worse by MBIR. CONCLUSION: Image quality, except regarding noise characteristics, and acceptance by radiologists were better by DLR than MBIR in low-dose CE-APCT by UHRCT.


Asunto(s)
Aprendizaje Profundo , Algoritmos , Humanos , Proyectos Piloto , Dosis de Radiación , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Radiólogos , Tomografía Computarizada por Rayos X/métodos
20.
Beilstein J Org Chem ; 17: 2939-2949, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34956414

RESUMEN

A genome mining survey combined with metabolome analysis of publicly available strains identified Couchioplanes sp. RD010705, a strain belonging to an underexplored genus of rare actinomycetes, as a producer of new metabolites. HPLC-DAD-guided fractionation of its fermentation extracts resulted in the isolation of five new methyl-branched unsaturated fatty acids, (2E,4E)-2,4-dimethyl-2,4-octadienoic acid (1), (2E,4E)-2,4,7-trimethyl-2,4-octadienoic acid (2), (R)-(-)-phialomustin B (3), (2E,4E)-7-hydroxy-2,4-dimethyl-2,4-octadienoic acid (4), (2E,4E)-7-hydroxy-2,4,7-trimethyl-2,4-octadienoic acid (5), and one prenylated tryptophan derivative, 6-(3,3-dimethylallyl)-N-acetyl-ʟ-tryptophan (6). The enantiomer ratio of 4 was determined to be approximately S/R = 56:44 by a recursive application of Trost's chiral anisotropy analysis and chiral HPLC analysis of its methyl ester. Compounds 1-5 were weakly inhibitory against Kocuria rhizophila at MIC 100 µg/mL and none were cytotoxic against P388 at the same concentration.

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