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1.
Melanoma Res ; 33(6): 547-552, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37696254

RESUMO

Proton beam therapy (PBT) has shown promising efficacy in treating locally advanced head and neck mucosal melanoma despite its poor prognosis. Although PBT may improve the efficacy of subsequent immune checkpoint inhibitors (ICIs), the safety of ICIs in patients who have previously received PBT has not been established. Hence, this study evaluated the safety of ICIs in patients who had recurrent mucosal melanoma after PBT. Between April 2013 and June 2022, we retrospectively reviewed the medical records of patients diagnosed with cutaneous or mucosal melanoma at the National Cancer Center Hospital East. Seven patients were treated with ICIs after their head and neck mucosal melanoma (HNMM) recurred after PBT. Four of the seven patients experienced grade immune-related adverse events (irAEs). Due to irAE in the irradiation field, two patients had grade 3 hypopituitarism. Other grade 3 or higher irAEs included an increase in serum alanine aminotransferase in two patients and gastritis in one, and two patients discontinued ICI due to the irAEs. All irAEs were resolved with appropriate management. Although administering ICIs after PBT may increase the risk of irAEs, especially in the irradiation field, they appear manageable. These findings could help in the development of a treatment strategy for locally advanced HNMM that includes PBT and subsequent ICIs.


Assuntos
Melanoma , Segunda Neoplasia Primária , Terapia com Prótons , Neoplasias Cutâneas , Humanos , Inibidores de Checkpoint Imunológico , Terapia com Prótons/efeitos adversos , Estudos Retrospectivos , Melanoma/tratamento farmacológico , Melanoma/radioterapia , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/radioterapia , Recidiva Local de Neoplasia
2.
Methods Mol Biol ; 2650: 133-140, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37310629

RESUMO

During embryonic development, the gut tube undergoes massive morphological changes from the simple tube structure composed of the pseudostratified epithelium into the mature intestinal tract composed of the columnar epithelium and characterized by the unique crypt-villus structures. In mice, maturation of fetal gut precursor cells into adult intestinal cells starts around embryonic day (E) 16.5, during which adult intestinal stem cells and their differentiated progenies are generated. In contrast to adult intestinal cells that form budding organoids containing both the crypt-like and villus-like regions, fetal intestinal cells can be cultured as simple spheroid-shaped organoids that show a uniform proliferation pattern. The fetal intestinal spheroids can undergo spontaneous maturation into adult budding organoids that contain intestinal stem cells and differentiated cells, including enterocytes, goblet, enteroendocrine, and Paneth cells, recapitulating intestinal cell maturation in vitro. Here, we provide detailed methods for establishment of fetal intestinal organoids and their differentiation into adult intestinal cells. These methods enable in vitro recapitulation of intestinal development and would be useful to reveal mechanisms that regulate the transition from fetal to adult intestinal cells.


Assuntos
Células-Tronco Adultas , Feto , Feminino , Gravidez , Animais , Camundongos , Duodeno , Enterócitos , Organoides
3.
Cancer Med ; 12(11): 12095-12105, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37012214

RESUMO

BACKGROUND: Since it was first reported in December 2019, coronavirus disease 2019 (COVID-19) spread rapidly across the globe resulting in a pandemic. As of August 2022, seven outbreak peaks have been confirmed in Tokyo, and the numbers of new cases in the fifth and later outbreak periods have been far greater than in the preceding periods. This retrospective study examined the impact of the COVID-19 pandemic on perioperative chemotherapy for breast cancer. METHODS: Patients with breast cancer who received perioperative chemotherapy at the National Cancer Center Hospital East were divided into 2 groups: 120 and 384 patients who started chemotherapy before and during the pandemic, respectively. The incidence of critical events that had potential detrimental effects on the prognosis, such as start of adjuvant chemotherapy ≥91 days after surgery and relative dose intensity of chemotherapy <85% were compared between groups. RESULTS: No significant difference in the incidence of critical events was found. When stratified by outbreak period, the incidence of critical events was positively correlated with the increasing number of new cases of COVID-19 (r = 0.83, p = 0.04). Moreover, 25/173 patients (14%) who started perioperative chemotherapy during the fifth and sixth outbreak periods developed COVID-19 infection, 80% of whom (20/25) had a delay or interruption to their surgery or other perioperative treatments. CONCLUSIONS: Although the impact of the COVID-19 pandemic on perioperative chemotherapy on whole groups of patients was not evident when comparing periods before and after the pandemic, the impact is becoming prominent in parallel with increasing numbers of new COVID-19 cases.


Assuntos
Neoplasias da Mama , COVID-19 , Humanos , Feminino , COVID-19/epidemiologia , Pandemias , SARS-CoV-2 , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/cirurgia , Estudos Retrospectivos
4.
BMC Ophthalmol ; 23(1): 177, 2023 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-37098507

RESUMO

BACKGROUND: A microfluidic real-time polymerase chain reaction (PCR) system can rapidly detect the viral DNA in specimens. Detection of herpes simplex virus (HSV) and varicella-zoster virus (VZV) DNA in tears is a useful diagnostic tool for herpes simplex virus keratitis (HSK) and herpes zoster ophthalmicus (HZO). METHODS: In total, 20 patients were included in this cross-sectional study. Among them, 8 patients with infectious epithelial HSK and 12 patients with HZO were included in HSK and HZO groups, respectively. In addition, 8 patients with non-herpetic keratitis and 4 healthy individuals without keratitis were included in the control group. Numbers of HSV and VZV DNA copies in tears of all patients and individuals were evaluated using a microfluidic real-time PCR system. Regarding HSV/VZV DNA test, tear specimens were collected by filter paper method using Schirmer's test paper, and subsequently, DNA was extracted from the filter paper using an automated nucleic acid extractor. Afterward, quantitative PCR was performed using a microfluidic real-time PCR system. RESULTS: From tear collection to real-time PCR result determination, the HSV/VZV DNA test took approximately 40 min. In the HSK group, the sensitivity and specificity of the HSV DNA tests were 100% each. The median value (range) of number of HSV DNA copies for affected eyes was 3.4 × 105 copies/µL (under a lower detection limit of 7.6). In the HZO group, the sensitivity and specificity of the VZV DNA tests were 100% each. The median value (range) of number of VZV DNA copies for affected eyes was 5.3 × 105 copies/µL (under a lower detection limit of 5.6 × 10-2). CONCLUSION: In conclusion, quantitative PCR for HSV and VZV DNA in tears using a microfluidic real-time PCR system is useful for diagnosing and monitoring HSK and HZO.


Assuntos
Herpes Simples , Herpesvirus Humano 1 , Ceratite Herpética , Humanos , Herpesvirus Humano 3/genética , Estudos Transversais , Microfluídica , Herpesvirus Humano 1/genética , Ceratite Herpética/diagnóstico , Herpes Simples/diagnóstico , Reação em Cadeia da Polimerase em Tempo Real/métodos , DNA Viral/análise
5.
Sci Rep ; 13(1): 2233, 2023 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-36788295

RESUMO

Neural regeneration is extremely difficult to achieve. In traumatic brain injuries, the loss of brain parenchyma volume hinders neural regeneration. In this study, neuronal tissue engineering was performed by using electrically charged hydrogels composed of cationic and anionic monomers in a 1:1 ratio (C1A1 hydrogel), which served as an effective scaffold for the attachment of neural stem cells (NSCs). In the 3D environment of porous C1A1 hydrogels engineered by the cryogelation technique, NSCs differentiated into neuroglial cells. The C1A1 porous hydrogel was implanted into brain defects in a mouse traumatic damage model. The VEGF-immersed C1A1 porous hydrogel promoted host-derived vascular network formation together with the infiltration of macrophages/microglia and astrocytes into the gel. Furthermore, the stepwise transplantation of GFP-labeled NSCs supported differentiation towards glial and neuronal cells. Therefore, this two-step method for neural regeneration may become a new approach for therapeutic brain tissue reconstruction after brain damage in the future.


Assuntos
Lesões Encefálicas Traumáticas , Células-Tronco Neurais , Camundongos , Animais , Hidrogéis , Neurônios , Lesões Encefálicas Traumáticas/terapia , Engenharia Tecidual/métodos , Alicerces Teciduais , Materiais Biocompatíveis , Diferenciação Celular
6.
Cancers (Basel) ; 14(23)2022 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-36497371

RESUMO

Retinoic acid (RA) and its synthetic derivatives, retinoids, have been established as promising anticancer agents based on their ability to regulate cell proliferation and survival. Clinical trials, however, have revealed that cancer cells often acquire resistance to retinoid therapy. Therefore, elucidation of underlying mechanisms of retinoid resistance has been considered key to developing more effective use of retinoids in cancer treatment. In this study, we show that constitutive activation of ERK MAP kinase signaling, which is often caused by oncogenic mutations in RAS or RAF genes, suppresses RA receptor (RAR) signaling in breast cancer cells. We show that activation of the ERK pathway suppresses, whereas its inhibition promotes, RA-induced transcriptional activation of RAR and the resultant upregulation of RAR-target genes in breast cancer cells. Importantly, ERK inhibition potentiates the tumor-suppressive activity of RA in breast cancer cells. Moreover, we also reveal that suppression of RAR signaling and activation of ERK signaling are associated with poor prognoses in breast cancer patients and represent hallmarks of specific subtypes of breast cancers, such as basal-like, HER2-enriched and luminal B. These results indicate that ERK-dependent suppression of RAR activity underlies retinoid resistance and is associated with cancer subtypes and patient prognosis in breast cancers.

7.
Allergy Asthma Clin Immunol ; 18(1): 89, 2022 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-36184619

RESUMO

BACKGROUND: Dupilumab-induced ocular surface disease (DIOSD) has been reported in patients with atopic dermatitis treated with dupilumab, and has been recognized as an adverse event of dupilumab. Our objective was to describe two cases of DIOSD with alterations in eotaxin-2 and interleukin (IL)-8 messenger ribonucleic acid (mRNA) expression on the ocular surface. CASE PRESENTATION: In the ocular surface test, specimens were collected from the patient's ocular surface, and eotaxin-2 and IL-8 mRNA levels in the specimens were measured using real-time polymerase chain reaction. The clinical score of ocular surface findings was quantified using a 5-5-5 exacerbation grading scale for allergic conjunctivitis. The first case was of a 27-year-old man who developed DIOSD 3 months after starting treatment with dupilumab injection for atopic dermatitis. After 5 weeks of topical instillation of tacrolimus ophthalmic suspension, the clinical score of ocular surface findings improved and IL-8 and eotaxin-2 mRNA expression levels gradually decreased. The second patient was a 55-year-old man who developed DIOSD 11 weeks after the start of treatment with dupilumab injection for atopic dermatitis. Four weeks after starting ophthalmological treatment with tacrolimus ophthalmic suspension, his clinical scores on ocular surface findings improved and IL-8 mRNA expression levels decreased. The ocular surface test in this case revealed increased expression levels of IL-8 mRNA on the ocular surface at the onset of DIOSD, which decreased with the improvement of objective findings. CONCLUSIONS: DIOSD, which has been successfully treated with tacrolimus ophthalmic suspension, may involve IL-8-related inflammation in addition to type 2 inflammation.

8.
Cornea ; 41(1): 23-30, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34870621

RESUMO

PURPOSE: To evaluate the clinical improvement and safety of prolonged treatment of vernal (VKC) and atopic keratoconjunctivitis (AKC) using topical tacrolimus. METHODS: We included 36 eyes of 36 patients who had VKC and AKC and were treated with topical tacrolimus ophthalmic suspension (0.1%) for 24 months. The demographic data of the enrolled patients were collected from their medical files. Clinical scores, remission rates, number of relapses, concomitant use of steroids, and refractory indices were assessed. Clinical outcomes were determined using papillae-limbus-cornea (PLC) scores and 5-5-5 exacerbation grading scale scores. Clinical characteristics associated with the need for concomitant steroid eye drops administration were determined using logistic regression analysis. All patients were classified into 3 subgroups using cluster analysis. RESULTS: PLC scores recorded in the sixth month were significantly improved compared with those recorded at baseline. PLC scores recorded in the 18th, 21st, and 24th months were significantly improved compared with those recorded in the sixth month. The remission rates increased diachronically and significantly, reaching 92% in the 24th month. Logistic regression analysis showed that, for every 10-year increase in patient age, the risk for requiring concomitant administration of steroid eye drops was reduced by half (odds ratio, 0.53; 95% confidence interval, 0.29-0.96). Using cluster analysis, the patients were divided into 3 clusters: adolescent type, pediatric type, and adult type. CONCLUSIONS: Two years of treatment with topical tacrolimus ophthalmic suspension is an effective method for inducing and maintaining the stable stages of VKC and AKC.


Assuntos
Conjuntivite Alérgica/tratamento farmacológico , Ceratoconjuntivite/tratamento farmacológico , Tacrolimo/administração & dosagem , Feminino , Seguimentos , Humanos , Imunossupressores/administração & dosagem , Masculino , Soluções Oftálmicas , Recidiva , Estações do Ano , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
9.
Cornea ; 41(10): 1232-1241, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34879043

RESUMO

PURPOSE: We investigated ocular surface microbiota dysbiosis in patients with refractory allergic conjunctival diseases (ACDs; stratified into mild and severe groups) treated with topical tacrolimus. METHODS: Patients (n = 21) with refractory ACDs (including vernal and atopic keratoconjunctivitis) actively treated with topical tacrolimus and 6 healthy controls were evaluated. Based on clinical scores and expression of specific cytokines on the ocular surface, patients with ACDs were divided into mild and severe groups using cluster analysis. The microbial composition of tear specimens collected from patients with mild and severe ACD and control subjects using the Schirmer test paper was determined through next-generation 16S rRNA sequencing analysis. RESULTS: Compared with healthy controls, patients with ACDs exhibited significantly decreased ocular surface microbiota α-diversity. Ocular surface microbiota mainly comprised members of the phyla Actinobacteria, Bacteroidetes, Firmicutes, and Proteobacteria in all groups. The relative abundance of ocular surface microbiota in patients with ACDs was increased for phylum Firmicutes and decreased for phylum Proteobacteria (compared with control subjects). The genera Blautia (vs. mild ACD group) and Morganella (vs. control group) exhibited significantly increased abundance only in the severe ACD group. CONCLUSIONS: The ocular surface microbiota in patients with severe ACD exhibited decreased diversity and exacerbation of dysbiosis compared with that in patients with mild ACD and control subjects. Patients with mild refractory ACD also exhibited decreased diversity of these microbiota. These alterations in microbiota indicated a change in the ocular surface of patients with refractory ACD (be it because of disease pathogenesis or topical immunomodulatory treatment).


Assuntos
Conjuntivite Alérgica , Microbiota , Túnica Conjuntiva/metabolismo , Conjuntivite Alérgica/metabolismo , Citocinas , Disbiose/microbiologia , Humanos , Microbiota/genética , RNA Ribossômico 16S/genética , Tacrolimo/uso terapêutico
10.
Acta Biomater ; 132: 272-287, 2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34023456

RESUMO

Recent advances in intestinal organoid technologies have paved the way for in vitro recapitulation of the homeostatic renewal of adult tissues, tissue or organ morphogenesis during development, and pathogenesis of many disorders. In vitro modelling of individual patient diseases using organoid systems have been considered key in establishing rational design of personalized treatment strategies and in improving therapeutic outcomes. In addition, the transplantation of organoids into diseased tissues represents a novel approach to treat currently incurable diseases. Emerging evidence from intensive studies suggests that organoid systems' development and functional maturation depends on the presence of an extracellular matrix with suitable biophysical properties, where advanced synthetic hydrogels open new avenues for theoretical control of organoid phenotypes and potential applications of organoids in therapeutic purposes. In this review, we discuss the status, applications, challenges and perspectives of intestinal organoid systems emphasising on hydrogels and their properties suitable for intestinal organoid culture. We provide an overview of hydrogels used for intestinal organoid culture and key factors regulating their biological activity. The comparison of different hydrogels would be a theoretical basis for establishing design principles of synthetic niches directing intestinal cell fates and functions. STATEMENT OF SIGNIFICANCE: Intestinal organoid is an in vitro recapitulation of the gut, which self-organizes from intestinal stem cells and maintains many features of the native tissue. Since the development of this technology, intestinal organoid systems have made significant contribution to rapid progress in intestinal biology. Prevailing methodology for organoid culture, however, depends on animal-derived matrices and suffers from variability and potential risk for contamination of pathogens, limiting their therapeutic application. Synthetic scaffold matrices, hydrogels, might provide solutions to these issues and deepen our understanding on how intestinal cells sense and respond to key biophysical properties of the surrounding matrices. This review provides an overview of developing intestinal models and biomaterials, thereby leading to better understanding of current intestinal organoid systems for both biologists and materials scientists.


Assuntos
Materiais Biocompatíveis , Organoides , Animais , Humanos , Hidrogéis , Células-Tronco , Tecnologia
11.
Cornea ; 39(9): 1177-1180, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32073453

RESUMO

PURPOSE: To report an atypical presentation of herpes simplex virus (HSV) keratitis followed up using expression levels of HSV DNA in tears. METHODS: A 22-year-old Japanese woman with hyperemia and foreign body sensation in her left eye was diagnosed with atypical dendritic keratitis. A slit-lamp examination at presentation indicated the presence of a rush of dendritic lesions with a sparse branching pattern and poor development of terminal bulbs; follicular conjunctivitis was also observed. Positivity for house-dust-mite- and cedar pollen-specific IgE antibodies in her serum indicated atopic diathesis. The HSV DNA levels in her tears were measured by a real-time polymerase chain reaction. RESULTS: At the initial visit, the HSV DNA levels in tears were 6.4 × 10 copies/sample in the right eye and 1.6 × 10 copies/sample in the left eye. The keratitis improved after treatment with topical acyclovir ointment, 5 times a day for 7 days, and systemic valacyclovir 1000 mg/d for 5 days. Multiple punctate subepithelial opacities developed in her left eye on day 7, with undetectable HSV DNA in tears, bilaterally. CONCLUSIONS: We have successfully monitored the HSV DNA levels in tears using quantitative real-time polymerase chain reaction in HSV keratitis where the corneal findings progressed from atypical dendritic keratitis to multiple punctate corneal subepithelial opacities during the treatment period.


Assuntos
Opacidade da Córnea/etiologia , DNA Viral/análise , Infecções Oculares Virais/virologia , Herpesvirus Humano 1/genética , Ceratite Dendrítica/virologia , Ceratite Herpética/virologia , Lágrimas/química , Antivirais/uso terapêutico , Opacidade da Córnea/diagnóstico , Opacidade da Córnea/metabolismo , Infecções Oculares Virais/tratamento farmacológico , Infecções Oculares Virais/metabolismo , Feminino , Humanos , Ceratite Dendrítica/tratamento farmacológico , Ceratite Dendrítica/metabolismo , Ceratite Herpética/tratamento farmacológico , Ceratite Herpética/metabolismo , Adulto Jovem
12.
J Biol Chem ; 294(1): 195-209, 2019 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-30409903

RESUMO

Lineage specification of the three germ layers occurs during early embryogenesis and is critical for normal development. The nucleosome remodeling and deacetylase (NuRD) complex is a repressive chromatin modifier that plays a role in lineage commitment. However, the role of chromodomain helicase DNA-binding protein 4 (CHD4), one of the core subunits of the NuRD complex, in neural lineage commitment is poorly understood. Here, we report that the CHD4/NuRD complex plays a critical role in neural differentiation of mouse embryonic stem cells (ESCs). We found that RNAi-mediated Chd4 knockdown suppresses neural differentiation, as did knockdown of methyl-CpG-binding domain protein Mbd3, another NuRD subunit. Chd4 and Mbd3 knockdowns similarly affected changes in global gene expression during neural differentiation and up-regulated several mesendodermal genes. However, inhibition of mesendodermal genes by knocking out the master regulators of mesendodermal lineages, Brachyury and Eomes, through a CRISPR/Cas9 approach could not restore the impaired neural differentiation caused by the Chd4 knockdown, suggesting that CHD4 controls neural differentiation by not repressing other lineage differentiation processes. Notably, Chd4 knockdown increased the acetylation levels of p53, resulting in increased protein levels of p53. Double knockdown of Chd4 and p53 restored the neural differentiation rate. Furthermore, overexpression of BCL2, a downstream factor of p53, partially rescued the impaired neural differentiation caused by the Chd4 knockdown. Our findings reveal that the CHD4/NuRD complex regulates neural differentiation of ESCs by down-regulating p53.


Assuntos
Diferenciação Celular , DNA Helicases/metabolismo , Regulação para Baixo , Neurônios/metabolismo , Nucleossomos/metabolismo , Proteína Supressora de Tumor p53/biossíntese , Animais , Linhagem Celular , DNA Helicases/genética , Técnicas de Silenciamento de Genes , Camundongos , Células-Tronco Embrionárias Murinas , Neurônios/citologia , Nucleossomos/genética , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteína Supressora de Tumor p53/genética
13.
Genes Cells ; 22(2): 189-202, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28097777

RESUMO

The Activin/Nodal/TGF-ß signaling pathway plays a major role in maintaining mouse epiblast stem cells (EpiSCs). The EpiSC-maintaining medium, which contains Activin A and bFGF, induces differentiation of mouse embryonic stem cells (ESCs) to EpiSCs. Here, we show that Activin A also has an ability to efficiently propagate ESCs without differentiation to EpiSCs when combined with a MEK inhibitor PD0325901. ESCs cultured in Activin+PD retained high-level expression of naive pluripotency-related transcription factors. Genomewide analysis showed that the gene expression profile of ESCs cultured in Activin+PD resembles that of ESCs cultured in 2i. ESCs cultured in Activin+PD also showed features common to the naive pluripotency of ESCs, including the preferential usage of the Oct4 distal enhancer and the self-renewal response to Wnt pathway activation. Our finding shows a role of Activin/Nodal/TGF-ß signaling in stabilizing self-renewal gene regulatory networks in ESCs.


Assuntos
Ativinas/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Células-Tronco Embrionárias Murinas/efeitos dos fármacos , Células-Tronco Embrionárias Murinas/metabolismo , Ativinas/química , Animais , Diferenciação Celular/fisiologia , Proliferação de Células/fisiologia , Células Cultivadas , Camadas Germinativas/citologia , Camadas Germinativas/metabolismo , Células HEK293 , Humanos , Sistema de Sinalização das MAP Quinases/fisiologia , Camundongos , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Quinases de Proteína Quinase Ativadas por Mitógeno/antagonistas & inibidores , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Células-Tronco Embrionárias Murinas/citologia , Células-Tronco Pluripotentes/citologia , Células-Tronco Pluripotentes/efeitos dos fármacos , Células-Tronco Pluripotentes/metabolismo , Fatores de Transcrição/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Via de Sinalização Wnt
14.
J Antibiot (Tokyo) ; 63(7): 365-9, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20588303

RESUMO

Surugapyrone A, a novel 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging 2-pyrone, was isolated from the culture filtrate of an actinomycete strain USF-6280. This strain was assigned to the genus Streptomyces owing to its morphological and chemotaxonomic characteristics. Phylogenetic analysis based on 16S ribosomal RNA gene sequences supported the classification of the producing strain as a member of the genus Streptomyces and indicated that it was closely related to Streptomyces coelicoflavus. As the morphological, physiological and biochemical characteristics of the producing strain were in agreement with those of the type strain of S. coelicoflavus, we concluded that strain USF-6280 should be identified as a member of S. coelicoflavus. The structure of surugapyrone A was determined to be 4-hydroxy-6-isopropyl-3-methyl-2-pyrone on the basis of the spectroscopic data. The results of feeding experiments with (13)C-labeled compounds indicated that surugapyrone A was biosynthesized through a polyketide pathway involving isobutyrate, acetate and propionate.


Assuntos
Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/farmacologia , Pironas/química , Pironas/farmacologia , Streptomyces/química , Compostos de Bifenilo/química , Sequestradores de Radicais Livres/isolamento & purificação , Espectroscopia de Ressonância Magnética , Microscopia Eletrônica de Varredura , Estrutura Molecular , Filogenia , Picratos/química , Pironas/isolamento & purificação , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Streptomyces/classificação , Streptomyces/genética , Streptomyces/ultraestrutura
15.
Biosci Biotechnol Biochem ; 74(6): 1293-4, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20530891

RESUMO

Two 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging compounds were isolated from soybean miso. They were determined to be 2,4,4'-trihydroxydeoxybenzoin and 3'-hydroxydaidzein on the basis of spectroscopic data. In the manufacturing process for soybean miso, 2,4,4'-trihydroxydeoxybenzoin appeared during culture aging, and the quantity of it increased in a time-dependent manner.


Assuntos
Benzoína/análogos & derivados , Benzoína/isolamento & purificação , Isoflavonas/isolamento & purificação , Alimentos de Soja , Benzoína/química , Benzoína/farmacologia , Cromatografia Líquida de Alta Pressão , Manipulação de Alimentos , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/isolamento & purificação , Sequestradores de Radicais Livres/farmacologia , Isoflavonas/química , Isoflavonas/farmacologia , Fatores de Tempo
16.
Biosci Biotechnol Biochem ; 74(4): 881-3, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20378968

RESUMO

Aspernolide A and butyrolactones I and II showed inhibitory activities against soybean lipoxygenase. All of them also had DPPH (2,2-diphenyl-1-picrylhydrazyl) radical-scavenging activity. An analysis of the mechanism for radical scavenging allowed us to deduce that aspernolide A was converted to a quinone methide by a reaction with two molecules of the DPPH radical.


Assuntos
Lipoxigenase/metabolismo , 4-Butirolactona/análogos & derivados , Compostos de Bifenilo , Dieta , Compostos Inorgânicos , Compostos Orgânicos , Picratos , Glycine max/enzimologia
17.
J Nat Prod ; 72(11): 2069-71, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19943625

RESUMO

Two new indole derivatives (3, 4) and three known compounds (1, 2, 5) were isolated as radical scavengers from the culture filtrate of a marine sponge-derived yeast. Their structures were determined to be tyrosol (1), tryptophol (2), 2-(1H-indol-3-yl)ethyl 2-hydroxypropanoate (3), 2-(1H-indol-3-yl)ethyl 5-hydroxypentanoate (4), and cyclo(L-Pro-L-Tyr) (5) on the basis of their spectroscopic data. The absolute configurations of compounds 3 and 5 were determined by chiral HPLC analysis combined with synthesis and Marfey's method, respectively. Each obtained compound was evaluated for DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging activity, and all compounds exhibited weak activities.


Assuntos
Compostos de Bifenilo/farmacologia , Sequestradores de Radicais Livres/isolamento & purificação , Indóis/isolamento & purificação , Pichia/química , Picratos/farmacologia , Poríferos/microbiologia , Animais , Cromatografia Líquida de Alta Pressão , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/farmacologia , Indóis/química , Indóis/farmacologia , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Peptídeos Cíclicos/química , Peptídeos Cíclicos/isolamento & purificação , Álcool Feniletílico/análogos & derivados , Álcool Feniletílico/química , Álcool Feniletílico/isolamento & purificação , Piperazinas/química , Piperazinas/isolamento & purificação
18.
Biosci Biotechnol Biochem ; 73(12): 2731-4, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19966460

RESUMO

Six compounds were isolated as radical scavengers from the culture broth of a marine-derived actinomycete strain USF-TC31. The structures of two novel compounds were determined to be those of N-carbamoyl-2,3-dihydroxybenzamide (5) and 2-acetamido-3-(2,3-dihydroxybenzoylthio)propanoic acid (6), and four known compounds were identified to be anthranilic acid (1), 2,3-dihydroxybenzoic acid (2), 2,3-dihydroxybenzamide (3) and benadrostin (4) on the basis of spectroscopic data. Compound 6 was characterized as a racemate by its specific rotation. Each of the obtained compounds was evaluated for DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging activity, and compounds 2, 3, 5 and 6 each exhibited potent activity in comparison with the butylhydroxytoluene (BHT) positive control.


Assuntos
Actinobacteria/química , Compostos de Bifenilo/química , Compostos de Bifenilo/isolamento & purificação , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/isolamento & purificação , Picratos/química , Picratos/isolamento & purificação , Actinobacteria/metabolismo , Catecóis/química , Catecóis/isolamento & purificação , Catecóis/metabolismo , Fermentação , Sequestradores de Radicais Livres/metabolismo , Espectroscopia de Ressonância Magnética , Oceanos e Mares
19.
Biosci Biotechnol Biochem ; 73(8): 1877-9, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19661709

RESUMO

Two compounds were isolated from biotransformation of daidzein, a soybean isoflavone, by Aspergillus oryzae. One was 6,7,8,4'-tetrahydroxyisoflavone, an A-ring dihydroxylated daidzein, and the other was a novel compound which had the cleaved B-ring of daidzein. The former was perhaps derived from 8-hydroxydaidzein and/or 6-hydroxydaidzein, and had high DPPH radical-scavenging activity.


Assuntos
Aspergillus oryzae/química , Aspergillus oryzae/metabolismo , Isoflavonas/isolamento & purificação , Isoflavonas/metabolismo , Compostos de Bifenilo/química , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/isolamento & purificação , Sequestradores de Radicais Livres/metabolismo , Isoflavonas/química , Espectroscopia de Ressonância Magnética , Picratos/química
20.
Biosci Biotechnol Biochem ; 73(6): 1355-61, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19502726

RESUMO

In our searching program for novel sorbicillin related compounds, three novel compounds, spirosorbicillinols A (1), B (2), and C (3), were isolated from the fermentation broth of the USF-4860 strain isolated from a soil sample. The planar structures of compounds 1-3 were determined from spectroscopic evidence and degradation reaction, and that of 1 was the same as that of 2. The relative stereochemistries of compounds 1-3 were determined by (1)H-(1)H coupling constants, the elucidation of HMBC and NOESY spectra in detail. 1 and 2 were stereoisomers at C8 position, each other. We propose that compounds 1 and 2 were formed by exo and endo intermolecular Diels-Alder reaction between sorbicillinol as a diene and scytolide (proposed precursor-1) as a dienophile, respectively. Similarly, we propose that compound 3 was formed by an endo intermolecular Diels-Alder reaction between sorbicillinol and proposed precursor-2.


Assuntos
Fungos/química , Resorcinóis/isolamento & purificação , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Resorcinóis/química , Resorcinóis/metabolismo , Espectrometria de Massas de Bombardeamento Rápido de Átomos , Estereoisomerismo
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