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1.
J Craniofac Surg ; 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38597603

RESUMO

The progression of a cervical abscess toward the mediastinum is rare but remains one of the most serious diseases, even in the era of antibiotics. A mediastinal abscess can originate from an odontogenic infection and presents a challenge for otolaryngologists and craniofacial surgeons, particularly when it spreads caudally to the tracheal bifurcation. For successful treatment of such an abscess, patients are generally referred to a thoracic surgeon for drainage. We present a distinctive case of an odontogenic infection-induced wide mediastinal abscess that could be drained only through cervical manipulation by using a sump-type tube. The patient was discharged on postoperative day 55 without any complications. This is the first report showing that descending mediastinal abscesses extending below the tracheal bifurcation could be drained by head and neck surgeons alone. The technique is easy and hence reproducible, safe, and convenient to perform.

2.
Cytotherapy ; 23(2): 176-183, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32978066

RESUMO

BACKGROUND AIMS: The Multisite Evaluation Study on Analytical Methods for Non-Clinical Safety Assessment of Human-Derived Regenerative Medical Products (MEASURE) is a Japanese experimental public-private partnership initiative, which aims to standardize methodology for tumorigenicity evaluation of human pluripotent stem cell (hPSC)-derived cell therapy products (CTPs). Undifferentiated hPSCs possess tumorigenic potential, and thus residual undifferentiated hPSCs are one of the major hazards for the risk of tumor formation from hPSC-derived CTPs. Among currently available assays, a highly efficient culture (HEC) assay is reported to be one of the most sensitive for the detection of residual undifferentiated hPSCs. METHODS: MEASURE first validated the detection sensitivity of HEC assay and then investigated the feasibility of magnetic-activated cell sorting (MACS) to improve sensitivity. RESULTS: The multisite experiments confirmed that the lower limit of detection under various conditions to which the human induced pluripotent stem cell lines and culture medium/substrate were subjected was 0.001%. In addition, MACS concentrated cells expressing undifferentiated cell markers and consequently achieved a detection sensitivity of 0.00002%. CONCLUSIONS: These results indicate that HEC assay is highly sensitive and robust and that the application of MACS on this assay is a promising tool for further mitigation of the potential tumorigenicity risk of hPSC-derived CTPs.


Assuntos
Técnicas de Cultura de Células , Terapia Baseada em Transplante de Células e Tecidos , Células-Tronco Pluripotentes Induzidas , Células-Tronco Pluripotentes , Diferenciação Celular , Separação Celular , Meios de Cultura , Humanos
3.
Br J Cancer ; 123(11): 1633-1643, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32921792

RESUMO

BACKGROUND: Annexin A1 is expressed specifically on the tumour vasculature surface. Intravenously injected IF7 targets tumour vasculature via annexin A1. We tested the hypothesis that IF7 overcomes the blood-brain barrier and that the intravenously injected IF7C(RR)-SN38 eradicates brain tumours in the mouse. METHODS: (1) A dual-tumour model was generated by inoculating luciferase-expressing melanoma B16 cell line, B16-Luc, into the brain and under the skin of syngeneic C57BL/6 mice. IF7C(RR)-SN38 was injected intravenously daily at 7.0 µmoles/kg and growth of tumours was assessed by chemiluminescence using an IVIS imager. A similar dual-tumour model was generated with the C6-Luc line in immunocompromised SCID mice. (2) IF7C(RR)-SN38 formulated with 10% Solutol HS15 was injected intravenously daily at 2.5 µmoles/kg into two brain tumour mouse models: B16-Luc cells in C57BL/6 mice, and C6-Luc cells in nude mice. RESULTS: (1) Daily IF7C(RR)-SN38 injection suppressed tumour growth regardless of cell lines or mouse strains. (2) Daily injection of Solutol-formulated IF7C(RR)-SN38 led into complete disappearance of B16-Luc brain tumour in C57BL/6 mice, whereas this did not occur in C6-Luc in nude mice. CONCLUSIONS: IF7C(RR)-SN38 crosses the blood-brain barrier and suppresses growth of brain tumours in mouse models. Solutol HS15-formulated IF7C(RR)-SN38 may have promoted an antitumour immune response.


Assuntos
Anexina A1/metabolismo , Antineoplásicos/farmacologia , Barreira Hematoencefálica/metabolismo , Neoplasias Encefálicas , Portadores de Fármacos/farmacologia , Animais , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos SCID , Peptídeos , Ratos
5.
Ann Surg Oncol ; 24(3): 778-784, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27714538

RESUMO

BACKGROUND: Total pharyngolaryngectomy and cervical esophagectomy (TPLCE) after chemoradiotherapy remains a challenge because of the high rate of complications and few available data on outcomes and safety. The purpose of this study was to evaluate the clinical significance of salvage TPLCE and to compare treatment outcomes between hypopharyngeal cancer and cervical esophageal cancer. METHODS: Data from 37 consecutive patients who were diagnosed with potentially resectable hypopharyngeal and cervical esophageal cancer after chemoradiotherapy were retrospectively analyzed. The survival and surgical outcomes were investigated between the hypopharyngeal cancer and cervical esophageal cancer groups. RESULTS: Twenty-six patients were included in hypopharyngeal cancer group and 11 patients were included in cervical esophageal cancer group. The baseline characteristics were balanced between the two groups. Compared to the hypopharyngeal cancer group, the cervical esophageal cancer group had significantly more frequent tracheal-related complications (p < 0.05) and stronger association of distal margin of the cervical esophagus and radiation field with tracheal ischemia after salvage surgery. CONCLUSIONS: Salvage TPLCE can offer the exclusive chance of prolonged survival. Association of tracheal ischemia with salvage TPLCE was seen more frequently for cervical esophageal cancer. Therefore, the indication for salvage TPLCE must be carefully considered to maintain the balance between curability and safety.


Assuntos
Neoplasias Esofágicas/terapia , Esofagectomia , Neoplasias Hipofaríngeas/terapia , Isquemia/etiologia , Laringectomia , Recidiva Local de Neoplasia/cirurgia , Faringectomia , Traqueia/irrigação sanguínea , Idoso , Idoso de 80 Anos ou mais , Quimiorradioterapia/efeitos adversos , Intervalo Livre de Doença , Esofagectomia/efeitos adversos , Esofagectomia/métodos , Feminino , Humanos , Laringectomia/efeitos adversos , Masculino , Pessoa de Meia-Idade , Neoplasia Residual , Faringectomia/efeitos adversos , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos , Terapia de Salvação/efeitos adversos , Taxa de Sobrevida , Doenças da Traqueia/etiologia , Resultado do Tratamento
6.
Development ; 138(19): 4143-53, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21852396

RESUMO

The availability of pluripotent stem cells offers the possibility of using such cells to model hepatic disease and development. With this in mind, we previously established a protocol that facilitates the differentiation of both human embryonic stem cells and induced pluripotent stem cells into cells that share many characteristics with hepatocytes. The use of highly defined culture conditions and the avoidance of feeder cells or embryoid bodies allowed synchronous and reproducible differentiation to occur. The differentiation towards a hepatocyte-like fate appeared to recapitulate many of the developmental stages normally associated with the formation of hepatocytes in vivo. In the current study, we addressed the feasibility of using human pluripotent stem cells to probe the molecular mechanisms underlying human hepatocyte differentiation. We demonstrate (1) that human embryonic stem cells express a number of mRNAs that characterize each stage in the differentiation process, (2) that gene expression can be efficiently depleted throughout the differentiation time course using shRNAs expressed from lentiviruses and (3) that the nuclear hormone receptor HNF4A is essential for specification of human hepatic progenitor cells by establishing the expression of the network of transcription factors that controls the onset of hepatocyte cell fate.


Assuntos
Regulação da Expressão Gênica no Desenvolvimento , Fator 4 Nuclear de Hepatócito/fisiologia , Hepatócitos/citologia , Fígado/embriologia , Células-Tronco Pluripotentes/citologia , Animais , Diferenciação Celular , Linhagem da Célula , Proliferação de Células , Fator 4 Nuclear de Hepatócito/metabolismo , Humanos , Lentivirus/genética , Camundongos , RNA Interferente Pequeno/metabolismo
7.
Auris Nasus Larynx ; 51(4): 631-635, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38626697

RESUMO

OBJECTIVES: This study aimed to evaluate the prognostic value of magnetic resonance imaging (MRI) findings in predicting local recurrence in patients with maxillary sinus cancer treated with super-selective intra-arterial infusion of high-dose cisplatin with concomitant radiotherapy (RADPLAT). METHODS: This single-center retrospective study included consecutive patients with maxillary sinus squamous cell carcinoma, who underwent RADPLAT between October 2016 and September 2021. MRI was performed before (within 2 weeks) and 1 month after (post-treatment MRI) the start of treatment. Tumor reduction rates and pre-treatment cross-sectional areas were calculated from the maximum cross-sectional areas on pre- and post-treatment MRI T2-weighted axial images. Statistical analyses, including receiver operating characteristic analysis, were performed to assess the predictive value of the tumor reduction rates. RESULTS: Twenty-four patients were included in this study. Recurrence occurred in seven patients with a median time of 213 days. The tumor reduction rates were significantly higher in the benign post-treatment changes group compared to the recurrence group (median, 0.814 vs. 0.174; p < 0.001). The cut-off value for the reduction rate between the groups was 0.3578. No significant difference was observed in the maximum pre-treatment cross-sectional area between the groups (p = 0.664). The inter-observer agreement for the tumor areas was excellent. CONCLUSIONS: The tumor reduction rate calculated from MRI T2-weighted images may be a predictor of local recurrence in patients with maxillary sinus cancer treated with RADPLAT. Patients with lower reduction rates may benefit from early salvage surgeries.

8.
Oral Oncol ; 154: 106868, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38820889

RESUMO

OBJECTIVES: Acute kidney injury (AKI) represents a major toxicity associated with cisplatin. We developed a risk prediction model for cisplatin-induced AKI in patients with postoperative high-risk head and neck cancer who received chemoradiotherapy during a randomized phase II/III trial, JCOG1008. MATERIALS AND METHODS: Two hundred and fifty-one patients received radiotherapy with weekly cisplatin at 40 mg/m2 (weekly arm) or 3-weekly cisplatin at 100 mg/m2 (3-weekly arm). AKI was defined using the AKI Network classification/staging system as increased serum creatinine of ≥0.3 mg/dL or a ≥1.5-fold increase from baseline 30 days after completing chemoradiotherapy. The Akaike information criterion was used to explore the optimal model by combining explanatory variables at registration. RESULTS: Among the 251 patients (210 men and 41 women (median age; 62 years)), 94 (37.5 %) developed cisplatin-induced AKI. The optimal cisplatin-induced AKI risk prediction model comprised four factors, including a primary site of hypopharynx/larynx (vs. oral cavity/oropharynx), 3-weekly arm (vs. weekly arm), serum albumin of ≤3.5 g/dL (vs. >3.5 g/dL) and creatinine clearance (CCr) of <90 mL/min (vs. ≥90 mL/min). The incidence of cisplatin-induced AKI rose with cumulative count of the four factors. When the cumulative count was ≥2, the positive predictive value for cisplatin-induced AKI was 50.3 %. CONCLUSIONS: We developed a risk prediction model for cisplatin-induced AKI in patients with head and neck cancer who received postoperative chemoradiotherapy using primary site, cisplatin administration method, serum albumin, and CCr. Patients with risk factors unrelated to the cisplatin administration method should adopt a weekly cisplatin regimen.


Assuntos
Injúria Renal Aguda , Quimiorradioterapia , Cisplatino , Neoplasias de Cabeça e Pescoço , Humanos , Cisplatino/efeitos adversos , Cisplatino/administração & dosagem , Masculino , Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/etiologia , Feminino , Pessoa de Meia-Idade , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/terapia , Quimiorradioterapia/efeitos adversos , Quimiorradioterapia/métodos , Idoso , Adulto , Antineoplásicos/efeitos adversos , Medição de Risco , Fatores de Risco
9.
Hepatology ; 56(6): 2163-71, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22653811

RESUMO

UNLABELLED: Elevated levels of low-density lipoprotein cholesterol (LDL-C) in plasma are a major contributor to cardiovascular disease, which is the leading cause of death worldwide. Genome-wide association studies (GWAS) have identified 95 loci that associate with control of lipid/cholesterol metabolism. Although GWAS results are highly provocative, direct analyses of the contribution of specific allelic variations in regulating LDL-C has been challenging due to the difficulty in accessing appropriate cells from affected patients. The primary cell type responsible for controlling cholesterol and lipid flux is the hepatocyte. Recently, we have shown that cells with hepatocyte characteristics can be generated from human induced pluripotent stem cells (iPSCs). This finding raises the possibility of using patient-specific iPSC-derived hepatocytes to study the functional contribution of GWAS loci in regulating lipid metabolism. To test the validity of this approach, we produced iPSCs from JD a patient with mutations in the low-density lipoprotein receptor (LDLR) gene that result in familial hypercholesterolemia (FH). We demonstrate that (1) hepatocytes can be efficiently generated from FH iPSCs; (2) in contrast to control cells, FH iPSC-derived hepatocytes are deficient in LDL-C uptake; (3) control but not FH iPSC-derived hepatocytes increase LDL uptake in response to lovastatin; and (4) FH iPSC-derived hepatocytes display a marked elevation in secretion of lipidated apolipoprotein B-100. CONCLUSION: Cumulatively, these findings demonstrate that FH iPSC-derived hepatocytes recapitulate the complex pathophysiology of FH in culture. These results also establish that patient-specific iPSC-derived hepatocytes could be used to definitively determine the functional contribution of allelic variation in regulating lipid and cholesterol metabolism and could potentially provide a platform for the identification of novel treatments of cardiovascular disease. (HEPATOLOGY 2012).


Assuntos
Hepatócitos/metabolismo , Hipercolesterolemia/genética , Lipoproteínas LDL/metabolismo , Células-Tronco Pluripotentes/fisiologia , Receptores de LDL/genética , Adolescente , Alelos , Anticolesterolemiantes/farmacologia , Apolipoproteína B-100/metabolismo , Diferenciação Celular , Células Cultivadas , LDL-Colesterol/metabolismo , Fibroblastos/fisiologia , Regulação da Expressão Gênica , Estudo de Associação Genômica Ampla , Hepatócitos/efeitos dos fármacos , Humanos , Hipercolesterolemia/fisiopatologia , Lovastatina/farmacologia , Masculino , Mutação , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 2/genética
11.
Head Neck ; 45(2): 521-528, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36336818

RESUMO

In traditional open maxillectomy, identifying the posterior margin is difficult because of its deep location and bleeding from the pterygoid venous plexus. Here, we present our endoscope-assisted total en bloc maxillectomy technique and discuss its merits and demerits compared to previously reported methods. We developed an endoscope-assisted total en bloc maxillectomy procedure. We reviewed a series of total maxillectomies performed with and without endoscopic assistance to verify the advantages of endoscopic assistance over conventional total maxillectomy. We analyzed (1) the precision using the distance of the remaining pterygoid process, (2) the operation time, and (3) blood loss. The length of the remnant pterygoid process was significantly shorter in the endoscopic assistance group. The operation time and blood loss were not significantly different between the two groups. Endoscopic assistance makes total maxillectomy more precise without requiring additional time and is a reasonable option for total maxillectomies.


Assuntos
Endoscopia , Margens de Excisão , Humanos , Endoscopia/métodos , Endoscópios , Craniotomia
12.
Radiol Case Rep ; 18(11): 4160-4166, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37732001

RESUMO

Carcinoma ex pleomorphic adenoma is a carcinoma that arises from a primary or recurrent benign pleomorphic adenoma. The prevalence of epithelial-myoepithelial carcinoma is low, and this histological type accounting for only 1% of all salivary gland tumors. Here, we report a rare case of Epithelial-Myoepithelial Carcinoma ex pleomorphic adenoma of the parotid gland with a radiologic-pathologic correlation.

13.
J Immunol ; 184(7): 3505-13, 2010 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-20190136

RESUMO

The cytokine response of macrophages to probiotic lactobacilli varies between strains, and the balance of IL-10/IL-12 production is crucial for determination of the direction of the immune response. To clarify the mechanism whereby Lactobacillus strains differentially induce production of IL-10 and IL-12, we examined the potential relationship between cytokine production and MAPK activation. In mouse peritoneal macrophages, Lactobacillus plantarum potently induced IL-10 but weakly induced IL-12 production, whereas L. casei potently induced IL-12 but weakly induced IL-10 production. Kinetic analysis of the activation of ERK, p38, and JNK showed that L. plantarum induced a more rapid and intense activation of MAPKs, especially of ERK, than L. casei. A selective blockade of ERK activation induced by L. plantarum resulted in a decrease in IL-10 production and a simultaneous increase in IL-12 production. Interestingly, when macrophages were stimulated with a combination of L. plantarum and L. casei, IL-10 production was induced synergistically. We identified cell wall teichoic acid and lipoteichoic acid as key factors for triggering the synergistic induction of IL-10 production, although these teichoic acids alone only weakly induced IL-10 production. The effect of these teichoic acids on IL-10 production was mediated by TLR2-dependent ERK activation. Our data demonstrate that activation of the ERK pathway is critical for determination of the balance of the IL-10/IL-12 response of macrophages to lactobacilli and that predominant IL-12 production induced by certain lactobacilli such as L. casei can be converted into predominant IL-10 production when stimulated in the presence of teichoic acids.


Assuntos
MAP Quinases Reguladas por Sinal Extracelular/imunologia , Interleucina-10/biossíntese , Interleucina-12/biossíntese , Lactobacillus/imunologia , Macrófagos Peritoneais/imunologia , Ácidos Teicoicos/imunologia , Animais , Western Blotting , Separação Celular , Ativação Enzimática/imunologia , Feminino , Citometria de Fluxo , Interleucina-10/imunologia , Interleucina-12/imunologia , Macrófagos Peritoneais/enzimologia , Camundongos , Camundongos Endogâmicos BALB C , RNA Mensageiro/análise , Transdução de Sinais/imunologia , Receptor 2 Toll-Like/imunologia
14.
Carbohydr Res ; 521: 108670, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36103733

RESUMO

The neutral polysaccharides LCPS-1 and LCPS-2 play functional roles in the cell wall of the lactic acid bacterium Lacticaseibacillus paracasei strain Shirota YIT 9029 (LcS; formerly Lactobacillus casei strain Shirota YIT 9029), which has long been used as a probiotic food product. Studies have shown that LCPS-1 is associated with the immunomodulatory functions of LcS. We hypothesized that the structure of LCPS-1 is crucial for elucidating the mechanism of action of LcS on host immune responses and aimed to solve the undetermined primary structure of LCPS-1. Our results showed that LCPS-1 has a molecular weight of >400 kDa and is composed of Glc, Rha, Gal, and GlcNAc, with a repeating structure. Using limited degradation reactions, including controlled Smith and deamination degradations, we obtained key fragments with low molecular weight. Subsequently, their structures were analyzed using NMR spectra and other analytical techniques. Further, we integrated the results for each key fragment to derive the complete structure of LCPS-1. Our results indicated that the most probable structure of LCPS-1 is composed of two types of units (X, Y), each with a basic structure of seven sugars in which the C2-position of Rha is substituted with an acetyl group. The structure of X is {6[Glcß1-2] Galα1-3[2-OAc] Rhaß1-4Glcß1-4[Rhaα1-3] [Glcα1-6] Glcß1-} and that of Y is {6[Glcß1-2] Galα1-3[2-OAc] Rhaß1-4Glcß1-4[Rhaα1-3] [Glcα1-6)] GlcNAcß1-}, which can be expressed as (X6Y12)n. In this study, we identified the primary structure of LCPS-1, and our results may enable an improved understanding of the immunomodulatory abilities of LcS.


Assuntos
Lacticaseibacillus casei , Parede Celular/metabolismo , Ácido Láctico/metabolismo , Lacticaseibacillus casei/metabolismo , Polissacarídeos/metabolismo , Açúcares/metabolismo
15.
Front Microbiol ; 13: 986396, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36016797

RESUMO

Selected lactic acid bacteria can stimulate macrophages and dendritic cells to secrete IL-12, which plays a key role in activating innate and cellular immunity. In this study, we investigated the roles of cell wall teichoic acids (WTAs) displayed on whole intact cell walls (ICWs) of Lactiplantibacillus plantarum in activation of mouse macrophages. ICWs were prepared from whole bacterial cells of several lactobacilli without physical disruption, and thus retaining the overall shapes of the bacteria. WTA-displaying ICWs of several L. plantarum strains, but not WTA-lacking ICWs of strains of other lactobacilli, elicited IL-12 secretion from mouse bone marrow-derived macrophages (BMMs) and mouse macrophage-like J774.1 cells. The ability of the ICWs of L. plantarum to induce IL-12 secretion was abolished by selective chemical elimination of WTAs from ICWs, but was preserved by selective removal of cell wall glycopolymers other than WTAs. BMMs prepared from TLR2- or TLR4-deficient mouse could secret IL-12 upon stimulation with ICWs of L. plantarum and a MyD88 dimerization inhibitor did not affect ICW-mediated IL-12 secretion. WTA-displaying ICWs, but not WTA-lacking ICWs, were ingested in the cells within 30 min. Treatment with inhibitors of actin polymerization abolished IL-12 secretion in response to ICW stimulation and diminished ingestion of ICWs. When overall shapes of ICWs of L. plantarum were physically disrupted, the disrupted ICWs (DCWs) failed to induce IL-12 secretion. However, DCWs and soluble WTAs inhibited ICW-mediated IL-12 secretion from macrophages. Taken together, these results show that WTA-displaying ICWs of L. plantarum can elicit IL-12 production from macrophages via actin-dependent phagocytosis but TLR2 signaling axis independent pathway. WTAs displayed on ICWs are key molecules in the elicitation of IL-12 secretion, and the sizes and shapes of the ICWs have an impact on actin remodeling and subsequent IL-12 production.

16.
Hepatology ; 51(1): 297-305, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19998274

RESUMO

UNLABELLED: There exists a worldwide shortage of donor livers available for orthotropic liver transplantation and hepatocyte transplantation therapies. In addition to their therapeutic potential, primary human hepatocytes facilitate the study of molecular and genetic aspects of human hepatic disease and development and provide a platform for drug toxicity screens and identification of novel pharmaceuticals with potential to treat a wide array of metabolic diseases. The demand for human hepatocytes, therefore, heavily outweighs their availability. As an alternative to using donor livers as a source of primary hepatocytes, we explored the possibility of generating patient-specific human hepatocytes from induced pluripotent stem (iPS) cells. CONCLUSION: We demonstrate that mouse iPS cells retain full potential for fetal liver development and describe a procedure that facilitates the efficient generation of highly differentiated human hepatocyte-like cells from iPS cells that display key liver functions and can integrate into the hepatic parenchyma in vivo.


Assuntos
Diferenciação Celular/fisiologia , Hepatócitos/transplante , Células-Tronco Pluripotentes Induzidas/fisiologia , Animais , Humanos , Camundongos
17.
J Nat Prod ; 74(11): 2329-31, 2011 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-22035372

RESUMO

Natural products obtained from marine invertebrates such as sponges and tunicates are attractive sources of drugs. However, a critical obstacle in the development of these compounds is the problem of supply. In most cases, neither chemical synthesis nor mariculture of invertebrates is economically feasible. Due to structural similarities, many marine natural products are suspected to be produced by associated microorganisms. A favorable strategy for the production of such compounds is to use culturable microorganisms. Here we report that didemnin B, a tunicate-derived depsipeptide, has been isolated from a culturable bacterium, Tistrella mobilis YIT 12409.


Assuntos
Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Depsipeptídeos/isolamento & purificação , Depsipeptídeos/farmacologia , Proteobactérias/química , Animais , Antineoplásicos/química , Depsipeptídeos/química , Ensaios de Seleção de Medicamentos Antitumorais , Células HT29 , Humanos , Japão , Biologia Marinha , Estrutura Molecular , Rhodospirillaceae , Simbiose , Urocordados/microbiologia
18.
PLoS One ; 16(1): e0241157, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33406123

RESUMO

We previously reported that IF7 peptide, which binds to the annexin A1 (ANXA1) N-terminus, functions as a tumor vasculature-targeted drug delivery vehicle after intravenous injection. To enhance IF7 stability in vivo, we undertook mirror-image peptide phage display using a synthetic D-peptide representing the ANXA1 N-terminus as target. We then identified peptide sequences, synthesized them as D-amino acids, and designated the resulting peptide dTIT7, which we showed bound to the ANXA1 N-terminus. Whole body imaging of mouse brain tumor models injected with near infrared fluorescent IRDye-conjugated dTIT7 showed fluorescent signals in brain and kidney. Furthermore, orally-administered dTIT7/geldanamycin (GA) conjugates suppressed brain tumor growth. Ours is a proof-of-concept experiment showing that ANXA1-binding D-peptide can be developed as an orally-administrable tumor vasculature-targeted therapeutic.


Assuntos
Anexina A1/antagonistas & inibidores , Neoplasias Encefálicas/irrigação sanguínea , Neoplasias Encefálicas/tratamento farmacológico , Sistemas de Liberação de Medicamentos , Proteínas de Neoplasias/antagonistas & inibidores , Neovascularização Patológica/tratamento farmacológico , Peptídeos , Administração Oral , Animais , Anexina A1/metabolismo , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Proteínas de Neoplasias/metabolismo , Neovascularização Patológica/metabolismo , Neovascularização Patológica/patologia , Peptídeos/síntese química , Peptídeos/química , Peptídeos/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
19.
iScience ; 24(11): 103363, 2021 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-34825137

RESUMO

Bifidobacterium bifidum YIT 10347 (BF-1) is adhesive in vitro. Here we studied the molecular aspects of the BF-1 adhesion process. We identified and characterized non-adhesive mutants and found that a class E housekeeping sortase was critical for the adhesion to mucin. These mutants were significantly less adhesive to GCIY cells than was the wild type (WT), which protected GCIY cells against acid treatment more than did a non-adhesive mutant. The non-adhesive mutants aberrantly accumulated precursors of putative sortase-dependent proteins (SDPs). Recombinant SDPs bound to mucin. Disruption of the housekeeping sortase influenced expression of SDPs and pilus components. Mutants defective in a pilin or in an SDP showed the same adhesion properties as WT. Therefore, multiple SDPs and pili seem to work cooperatively to achieve adhesion, and the housekeeping sortase is responsible for cell wall anchoring of its substrates to ensure their proper biological function.

20.
BMC Dev Biol ; 10: 60, 2010 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-20525219

RESUMO

BACKGROUND: To maintain pluripotency of human embryonic stem (huES) cells in feeder-free culture it has been necessary to provide a Matrigel substratum, which is a complex of poorly defined extracellular matrices and growth factors derived from mouse Engelbreth-Holm-Swarm sarcoma cells. Culture of stem cells under ill-defined conditions can inhibit the effectiveness of maintaining cells in a pluripotent state and reduce reproducibility of differentiation protocols. Moreover recent batches of Matrigel have been found to be contaminated with the single stranded RNA virus, Lactate Dehydrogenase Elevating Virus (LDEV), raising concerns regarding the safety of using stem cells that have been cultured on Matrigel in a therapeutic setting. To circumvent such concerns, we attempted to identify a recombinant matrix that could be used as an alternative to Matrigel for the culture of human pluripotent stem cells. huES and human induced pluripotent stem (hiPS) cells were grown on plates coated with a fusion protein consisting of E-cadherin and the IgG Fc domain using mTeSR1 medium. RESULTS: Cells grown under these conditions maintained similar morphology and growth rate to those grown on Matrigel and retained all pluripotent stem cell features, including an ability to differentiate into multiple cell lineages in teratoma assays. We, therefore, present a culture system that maintains the pluripotency of huES and hiPS cells under completely defined conditions. CONCLUSIONS: We propose that this system should facilitate growth of stem cells using good manufacturing practices (GMP), which will be necessary for the clinical use of pluripotent stem cells and their derivatives.


Assuntos
Caderinas , Técnicas de Cultura de Células , Células-Tronco Embrionárias/citologia , Células-Tronco Pluripotentes/citologia , Animais , Meios de Cultura , Humanos , Camundongos , Proteínas Recombinantes de Fusão/metabolismo
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