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1.
Biogerontology ; 24(4): 581-592, 2023 08.
Article de Anglais | MEDLINE | ID: mdl-37052773

RÉSUMÉ

There is growing evidence that extracellular vesicles (EVs) play a functional role in tissue repair and anti-aging by transferring the contents of donor cells to recipient cells. We hypothesized that Dauer (C. elegans), known as "ageless" nematodes, can also secrete extracellular vesicles and influence the lifespan of C. elegans. Here, we isolated EVs of dauer larvae (dauer EVs). Dauer EVs were characterized using transmission electron microscopy, nanoparticle tracking analysis (NTA), and Western blot analysis. Wild-type C. elegans were fed in the presence or absence of dauer EVs and tested for a range of phenotypes, including longevity, mobility and reproductive capacity. Results showed that dauer EVs increased the average lifespan of nematodes by 15.74%, improved mobility, slowed age-related pigmentation as well as body length, and reduced the accumulation of reactive oxygen species and lipids, while not impairing nematode reproductive capacity. These findings suggest that dauer EVs can extend the lifespan of C. elegans as well as the healthy lifespan by reducing ROS accumulation, with potential anti-aging capacity.


Sujet(s)
Protéines de Caenorhabditis elegans , Vésicules extracellulaires , Animaux , Caenorhabditis elegans/génétique , Larve , Vieillissement , Protéines de Caenorhabditis elegans/génétique , Longévité/génétique
2.
Front Oncol ; 12: 797349, 2022.
Article de Anglais | MEDLINE | ID: mdl-35419281

RÉSUMÉ

Background: The study was conducted to explore whether high-intensity focused ultrasound (HIFU) can improve the effect of transcatheter arterial chemoembolization (TACE) in intermediate and advanced hepatocellular carcinoma (HCC). Methods: PubMed, Embase, Cochrane Library, Web of Science, Wanfang Data, CQVIP, China National Knowledge Infrastructure (CNKI), and Chinese Biomedical (CBM) databases were searched for randomized controlled trials (RCTs) comparing the effect of TACE in combination with HIFU group (group A) to TACE alone group (group B) in treating intermediate and advanced HCC. The primary outcomes were overall survival (OS) rate and tumor response rate. The odds ratio (OR) and 95% confidence interval (CI) for each study were calculated and then pooled with fixed effects model or random effects model. Sensitivity analyses and subgroup analyses were conducted. A publication bias was also evaluated. Results: After literature selection, eleven RCTs involving 803 patients were included in this meta-analysis. This meta-analysis revealed that group A was associated with an increased 6-month OS rate (OR = 0.20), 12-month OS rate (OR = 0.23), 24-month OS rate (OR = 0.32), and overall response rate (WHO criterion, OR = 0.22; RECIST criterion, OR = 0.30). Furthermore, subgroup analyses showed no bias in the result. Given the limited number of studies that reported major complications, no additional meta-analysis of complication was conducted. Despite no special treatment, any complication following HIFU treatment was found to subside within 3-7 days. Conclusion: TACE in combination with HIFU is associated with increased OS and tumor response in intermediate and advanced HCC. Current evidence supports the use of HIFU after TACE treatment in intermediate and advanced HCC.

3.
Cells ; 10(12)2021 11 29.
Article de Anglais | MEDLINE | ID: mdl-34943854

RÉSUMÉ

Previous studies have revealed that high-intensity focused ultrasound (HIFU) ablation can trigger an antitumor immune response. The aim of this study was to investigate immune response in tumor-draining lymph nodes (TDLNs) after HIFU treatment. Forty-eight female patients with biopsy-confirmed breast cancer were divided into a control group and an HIFU group. In the control group, 25 patients underwent modified radical mastectomy, but 23 patients in the HIFU group received HIFU ablation of primary cancer, followed by the same operation. Using HE and immunohistochemical staining, the immunologic reactivity pattern and immune cell profile were assessed in paraffin-embedded axillary lymph nodes (ALNs) in all patients. The results showed that ALNs presented more evident immune reactions in the HIFU group than in the control group (100% vs. 64%). Among the ALNs, 78.3% had mixed cellular and humoral immune response, whereas 36% in the control group showed cellular immune response. The numbers of CD3+, CD4+, NK cell, and activated CTLs with Fas ligand+, granzyme+ and perforin+ expression were significantly higher in the ALNs in the HIFU group. It was concluded that HIFU could stimulate potent immune response and significantly increase T cell, activated CTLs and NK cell populations in the TDLNs of breast cancer.


Sujet(s)
Tumeurs du sein/immunologie , Tumeurs du sein/chirurgie , Ablation par ultrasons focalisés de haute intensité , Immunité , Noeuds lymphatiques/immunologie , Adulte , Sujet âgé , Aisselle/anatomopathologie , Femelle , Humains , Adulte d'âge moyen , Lymphocytes T cytotoxiques/immunologie , Jeune adulte
4.
Front Surg ; 8: 663128, 2021.
Article de Anglais | MEDLINE | ID: mdl-34150838

RÉSUMÉ

Objective: To evaluate factors in predicting the treatment outcome of ultrasound-guided high-intensity focused ultrasound (USgHIFU) ablation for uterine fibroids with a non-perfused volume ratio (NPVR) of at least 80%. Methods: One thousand patients with uterine fibroids who received USgHIFU were enrolled. Thirty-two independent variables of four dimensions of data set, including general information of patients, clinical symptoms, laboratory tests, and fibroid imaging characteristics, were used to investigate the potential predictors of the NPVR of at least 80% by multivariate logistic regression. NPVR was the gold standard for evaluating the efficiency of HIFU ablation, and a NPVR of at least 80% was considered sufficient ablation, while partial ablation was defined as having an NPVR of <80%. Results: Out of 1,000 fibroids, 758 obtained sufficient ablation and 242 obtained partial ablation, and the median NPVR was 88.3% (interquartile range: 80.3-94.8%). The probability of NPVR reaching 80% fibroids with a signal intensity of T2WI of hypointense, isointense, and hyperintense was 86.4, 76.5, and 62.6%, respectively; fibroids with an enhancement type of T1WI of slight, irregular, and regular was 81.5, 73.6, and 63.7%, respectively; and fibroids with uterine anteroposterior of 30-130 mm was 57.7-78.3%, respectively. In patients with a platelet count of 50 × 109/L-550 × 109/L, the probability of NPVR reaching 80% is from 53.4 to 80.1%, respectively. Conclusions: In predicting NPVR ≥ 80%, the signal intensity on T2WI was the most important factor affecting ablative efficiency, followed by enhancement type on T1WI, uterine anteroposterior, and platelet count.

5.
J Pharm Sci ; 110(6): 2416-2422, 2021 06.
Article de Anglais | MEDLINE | ID: mdl-33387598

RÉSUMÉ

Sterile filtration is an effective method to remove any microorganisms present during nanoemulsion preparation. However, it lacks effective control parameters. Here, we established a simple and rapid approach for the process control of nanoemulsion sterile filtration by utilizing optical density detection as a process control parameter. During sterile filtration, the optical density or optical density ratio of the filtrate were continuously monitored to explore the correlation between optical density and the emulsion content and the change in the optical density ratio before and after sterile filtration. In the emulsion stability test, the optical density ratio was determined. A good correlation was obtained between the optical density and the nanoemulsion content during sterile filtration, thereby reducing sterile filtration loss. The optical density ratio changed significantly after sterile filtration, indicating that it could be used as a process control parameter to monitor leakage during emulsion sterile filtration. The optical density ratio can be a characterization index for stability monitoring as it is more sensitive than particle size detection and more convenient than large particle detection. These parameters may be used for sterile filtration process control and as an index for nanoemulsion characterization. This approach overcomes the limitations of existing nanoemulsion characterization methods.


Sujet(s)
Filtration , Émulsions , Taille de particule
6.
Front Oncol ; 11: 725193, 2021.
Article de Anglais | MEDLINE | ID: mdl-34993130

RÉSUMÉ

PURPOSE: This study aimed to compare the dose and effectiveness of ultrasound-guided high-intensity focused ultrasound (USgHIFU) ablation of uterine fibroids with different sizes and explore the effect of uterine fibroid size on dose, which provided dose evaluation for clinicians in accordance with the size of uterine fibroids. MATERIALS AND METHODS: A total of 1,000 patients with symptomatic uterine fibroids who received a single-session USgHIFU treatment were enrolled in this study. The size of fibroids was divided into seven groups: 3-4 cm, 4-5 cm, 5-6 cm, 6-7 cm, 7-8 cm, 8-9 cm, and 9-11 cm. The dose was expressed on the basis of the energy efficiency factor (EEF) as the energy required for ablation per unit volume of tissue, and the non-perfused volume ratio (NPVR) was used to assess the effect of HIFU ablation. RESULTS: The median NPVR of 88.3% (IQR: 80.3%-94.8%) was obtained, and no significant difference was observed among the seven groups. The classification of T2-weighted image signal intensity fibroids in the 4-5 cm group was compared with that in the 6-7 cm and 8-9 cm groups, and the difference was significant (p < 0.05). However, the proportion of T2WI hyperintense signal fibroids had no significant difference among the seven groups (p > 0.05). The median EEF was 3.88 J/mm3, and a significant difference was observed among the seven groups of EEF (p < 0.05). The EEF of groups with a fibroid size less than 6 cm was more than double the EEF of groups with a fibroid size above 6 cm. In addition, the EEF of groups with a fibroid size of 4-5 cm and 3-4 cm was 3-4 times higher than those with a fibroid size above 7 cm (p < 0.05). CONCLUSIONS: A single-session HIFU ablation for uterine fibroids of 3-11 cm can obtain an NPVR of more than 80%. The EEF decreased with the increase of the size of uterine fibroids. A fibroid size of 6.5 cm was considered as a clinical meaningful point affecting EEF.

7.
Ultrasound Med Biol ; 46(7): 1677-1685, 2020 07.
Article de Anglais | MEDLINE | ID: mdl-32359807

RÉSUMÉ

The aim of the study described here was to compare the effectiveness of focused ultrasound surgery (FUS), which uses high-intensity focused ultrasound to perform tissue ablation, with that of hysteroscopic transcervical resection of myoma (TCRM) for the treatment of type 2 submucosal fibroids. A prospective cohort study was performed in patients who underwent FUS or TCRM from January 2012 to December 2014. Uterine Fibroid Symptom (UFS) and Quality of Life (QoL) questionnaires were used to measure fibroid-related symptoms and quality of life before and at 3, 6 and 12 mo after treatment. Technical results, adverse events and post-operative recovery times of both groups were also compared. A total of 81 patients with at least one type 2 submucosal fibroid were enrolled. The mean diameter of type 2 submucosal fibroids was 3.8 ± 0.9 cm (range: 2.0-5.0 cm) for 39 patients in the FUS group and 3.5 ± 0.8 cm (range: 2.0-4.8 cm) for the 42 patients enrolled in the TCRM group. No major complication occurred in any patients for either treatment. In both groups, the UFS score decreased significantly and the QoL score increased significantly from baseline successively at 3, 6 and 12 mo post-treatment (p < 0.05). Time spent in hospital post-treatment was significantly shorter (2.56 ± 0.98 d) for the FUS group compared with the TCRM group (3.31 ± 0.60 d) (p < 0.05). Time to return to work after treatment was also significantly shorter for the FUS group (3.14 ± 0.83 d) than for the TCRM group (6.09 ± 0.9 d) (p < 0.05). FUS and TCRM are both tolerable and effective treatments with significant improvement of symptom and quality of life for patients with type 2 submucosal fibroids ≤5 cm in diameter.


Sujet(s)
Ablation par ultrasons focalisés de haute intensité/méthodes , Hystéroscopie/méthodes , Léiomyome/chirurgie , Adulte , Femelle , Humains , Adulte d'âge moyen , Qualité de vie , Enquêtes et questionnaires , Résultat thérapeutique , Jeune adulte
8.
Vaccines (Basel) ; 8(1)2020 Mar 13.
Article de Anglais | MEDLINE | ID: mdl-32183209

RÉSUMÉ

Traditional aluminum adjuvants can trigger strong humoral immunity but weak cellular immunity, limiting their application in some vaccines. Currently, various immunomodulators and delivery carriers are used as adjuvants, and the mechanisms of action of some of these adjuvants are clear. However, customizing targets of adjuvant action (cellular or humoral immunity) and action intensity (enhancement or inhibition) according to different antigens selected is time-consuming. Here, we review the adjuvant effects of some delivery systems and immune stimulants. In addition, to improve the safety, effectiveness, and accessibility of adjuvants, new trends in adjuvant development and their modification strategies are discussed.

9.
Korean J Radiol ; 19(4): 724-732, 2018.
Article de Anglais | MEDLINE | ID: mdl-29962878

RÉSUMÉ

Objective: The purpose of this study was to compare efficacy, sonication energy efficiency, treatment time and safety of magnetic resonance-guided high-intensity focused ultrasound (MRgHIFU) and those of ultrasound-guided high-intensity focused ultrasound (USgHIFU) for ablation of uterine fibroids. Materials and Methods: This study included 43 patients with 44 symptomatic uterine fibroids treated with MRgHIFU and 51 patients with 68 symptomatic uterine fibroids treated with USgHIFU. After therapy, contrast-enhanced MRI was conducted and complete ablation was defined as 100% non-perfused volume (NPV) of fibroids. Patients with completely ablated fibroids were selected for the comparison of the treatment data and sonication parameters between MRgHIFU and USgHIFU treated groups. Results: Thirteen completely ablated fibroids in 10 patients (23.3%, 10/43) were achieved with MRgHIFU and 28 completely ablated fibroids in 22 patients (43.1%, 22/51) were achieved with USgHIFU. In completely ablated fibroids, the energy-efficiency factor (EEF) was 5.1 ± 3.0 J/mm3 and 4.7 ± 2.5 J/mm3 in the MRgHIFU and USgHIFU, respectively (p = 0.165). There was a negative linear correlation between EEF and the NPV of fibroids for MRgHIFU (p = 0.016) and USgHIFU (p = 0.001). The mean treatment time was 174.5 ± 42.2 minutes and 114.4 ± 39.2 minutes in the MRgHIFU and USgHIFU procedures, respectively (p = 0.021). There were no severe adverse events and major complications after treatment. Conclusion: MRgHIFU and USgHIFU are safe and effective with the equivalent energy efficiency for complete ablation of fibroids. USgHIFU has shorter treatment time than MRgHIFU.


Sujet(s)
Ablation par ultrasons focalisés de haute intensité/méthodes , Léiomyome/chirurgie , Imagerie par résonance magnétique , Échographie , Tumeurs de l'utérus/chirurgie , Adulte , Femelle , Humains , Adulte d'âge moyen , Études prospectives , Résultat thérapeutique
10.
Int J Hyperthermia ; 34(8): 1298-1303, 2018 12.
Article de Anglais | MEDLINE | ID: mdl-29506421

RÉSUMÉ

OBJECTIVE: To investigate the factors which may cause thermal injury of abdominal wall structures in ultrasound-guided high-intensity focussed ultrasound (USgHIFU) ablation of uterine fibroids. METHOD: A total of 892 patients with uterine fibroids diagnosed on contrast-enhanced magnetic resonance imaging (MRI) scans received HIFU ablation and follow-up MRI scanning. After therapy, thermal injury to the skin was assessed via measurement of skin redness, blisters, subcutaneous nodules and to the abdominal wall structures via measurement of signal intensity on T2-weighted MRI images. A total of 151 patients were assigned to the injury group, 741 patients were assigned to the non-injury group. The relationship between patient and treatment parameters and injury were analysed using univariate and multiple logistic regression analyses. RESULTS: Univariate logistic regression revealed that sonication time, sonication time per hour, total energy deposited, distance from uterine fibroid ventral side to skin, volume of uterine fibroids, abdominal wall scar, abdominal wall thickness and body mass index (BMI) all affected whether thermal injury occurred (p < 0.05). Subsequently, multiple logistic regression analysis revealed that total energy (p = 0.000, OR = 2.228, 95% CI 1.831-2.712), abdominal wall scar (p = 0.019, OR = 1.639, 95% CI 1.085-2.477) and abdominal wall thickness (p = 0.000, OR = 1.562, 95% CI 1.313-1.857) were significantly correlated with thermal injury. CONCLUSION: Multiple logistic regression analysis revealed that abdominal wall thickness, total energy and abdominal wall scar were the most significant influencing factors that influenced minimal thermal injury of abdominal wall structures in USgHIFU ablation of uterine fibroids.


Sujet(s)
Brûlures/étiologie , Ablation par ultrasons focalisés de haute intensité/effets indésirables , Léiomyome/chirurgie , Tumeurs de l'utérus/chirurgie , Paroi abdominale , Adulte , Femelle , Humains , Léiomyome/imagerie diagnostique , Imagerie par résonance magnétique , Adulte d'âge moyen , Peau , Tumeurs de l'utérus/imagerie diagnostique
11.
Chem Biodivers ; 14(5)2017 May.
Article de Anglais | MEDLINE | ID: mdl-28130826

RÉSUMÉ

One new ent-kaurane diterpenoid, 11ß,16α-dihydroxy-ent-kauran-19-oic acid (1), together with eight known analogues 2 - 9 were isolated from the aerial parts of Wedelia prostrata. One of the acidic diterpenoids, kaurenoic acid (3), was converted to seven derivatives, 10 - 16. All compounds were evaluated for their cytotoxic activity in vitro against human leukemia (K562), liver (HepG-2), and stomach (SGC-7901) cancer cell lines. Only four kaurenoic acid derivatives, 13 - 16, with 15-keto and substitutions at C(19) position, exhibited notable cytotoxic activities on these tumor cell lines with IC50 value ranging from 0.05 to 3.71 µm. Compounds 10 - 12, with oxime on C(15) showed moderate inhibitory effects and compounds 1 - 9 showed no cytotoxicities on them. Structure-activity relationships were also discussed based on the experimental data obtained. The known derivative, 15-oxokaurenoic acid 4-piperdin-1-ylbutyl ester (17), induced typical apoptotic cell death in colon SW480 cells upon evaluation of the apoptosis-inducing activity by flow-cytometric analysis.


Sujet(s)
Diterpènes/isolement et purification , Diterpènes/toxicité , Wedelia/composition chimique , Antinéoplasiques d'origine végétale/isolement et purification , Antinéoplasiques d'origine végétale/pharmacologie , Apoptose/effets des médicaments et des substances chimiques , Mort cellulaire/effets des médicaments et des substances chimiques , Lignée cellulaire tumorale , Diterpènes de type kaurane/isolement et purification , Cellules HepG2 , Humains , Concentration inhibitrice 50 , Cellules K562 , Parties aériennes de plante/composition chimique , Relation structure-activité
12.
Med Sci Monit ; 22: 4542-4554, 2016 Nov 24.
Article de Anglais | MEDLINE | ID: mdl-27885249

RÉSUMÉ

BACKGROUND The complex process by which lactation is initiated upon neonate delivery remains incompletely understood. Microvesicles (MVs) can transmit microRNAs (miRNAs) into recipient cells to influence cell function, and recent studies have identified miRNAs essential for mammary gland development and lactation. This study aimed to investigate the expression of lactation-related miRNAs in MVs isolated from human umbilical cord blood immediately after delivery. MATERIAL AND METHODS Umbilical cord blood samples were collected from 70 healthy pregnant women, and MVs were isolated through differential centrifugation and characterized by transmission electron microscopy, Western blotting, and nanoparticle tracking analysis. Lactation-related miRNAs were screened using bioinformatics tools for miRNA target prediction, gene ontology, and signaling pathway analyses. miRNA PCR arrays were used for miRNA expression analysis, and the results were validated by real-time PCR. Upon exposure of HBL-100 human mammary epithelial cells to MVs, MV uptake was examined by fluorescence confocal microscopy and b-casein secretion was detected by ELISA. RESULTS Spherical MVs extracted from umbilical cord blood expressed CD63 and had an average diameter of 167.0±77.1 nm. We profiled 337 miRNAs in human umbilical cord blood MVs and found that 85 were related to lactation by bioinformatics analysis. The 25 most differentially expressed lactation-related miRNAs were validated by real-time PCR. MV uptake by HBL-100 cells was after 4 h in culture, and significantly increased secretion of ß-casein was observed after 96 h from cells exposed to MVs (P<0.05). CONCLUSIONS Umbilical cord blood MVs contain many lactation-related miRNAs and can induce ß-casein production by HBL-100 cells in vitro. Thus, umbilical cord blood MVs may mediate secretion of ß-casein through miRNAs, thereby playing an important role in fetal-maternal crosstalk.


Sujet(s)
Microparticules membranaires/métabolisme , Sang foetal/métabolisme , Lactation/physiologie , microARN/biosynthèse , Adulte , Microparticules membranaires/génétique , Cellules cultivées , Femelle , Humains , microARN/génétique , Grossesse , Cordon ombilical/métabolisme , Cordon ombilical/ultrastructure
13.
Oncotarget ; 7(31): 50450-50460, 2016 Aug 02.
Article de Anglais | MEDLINE | ID: mdl-27391071

RÉSUMÉ

High intensity focused ultrasound (HIFU) technology is becoming a potential noninvasive treatment for solid tumor. To explore whether HIFU can be applied to treat melanoma and its metastasis, we investigated the effect of HIFU on murine melanoma model. While there was little influence on cell survival, viability or apoptosis, HIFU exposure suppressed melanoma cell migration in vitro and metastasis in vivo. The expression of microRNA-21(miR-21) was down-regulated and PTEN expression was up-regulated in response to HIFU exposure, which was in concomitant with the reduction of AKT activity. Furthermore, ectopic miR-21 expression suppressed this effect of HIFU. These results demonstrate that HIFU exposure can inhibit AKT-mediated melanoma metastasis via miR-21 inhibition to restore PTEN expression. Therefore, targeting the miR-21/PTEN/AKT pathway might be a novel strategy of HIFU in treatment of melanoma.


Sujet(s)
Mélanome expérimental/métabolisme , Mélanome expérimental/thérapie , microARN/métabolisme , Phosphohydrolase PTEN/métabolisme , Tumeurs cutanées/métabolisme , Tumeurs cutanées/thérapie , Ultrasonothérapie/méthodes , Animaux , Apoptose , Mouvement cellulaire , Survie cellulaire , Régulation négative , Femelle , Souris , Souris de lignée C57BL , Métastase tumorale , Transplantation tumorale , Régulation positive
14.
Chem Biodivers ; 13(12): 1738-1746, 2016 Dec.
Article de Anglais | MEDLINE | ID: mdl-27449157

RÉSUMÉ

Four new tirucallane triterpenoids, (21S,23R,24R)-21,23-epoxy-21,24-dihydroxy-25-methoxytirucall-7-en-3-one (2), (3S,21S,23R,24S)-21,23-epoxy-21,25-dimethoxytirucall-7-ene-3,24-diol (8), (21S,23R,24R)-21,23-epoxy-24-hydroxy-21-methoxytirucalla-7,25-dien-3-one (11), and (21S,23R,24R)-21,23-epoxy-21,24-dihydroxytirucalla-7,25-dien-3-one (12), along with 16 known analogues, 1, 3 - 7, 9 - 10, and 13 - 20, were isolated from the fruits of Melia azedarach. Their structures were elucidated by spectroscopic methods including 1D- and 2D-NMR techniques and mass spectrometry. These compounds were evaluated for their cytotoxicities against HepG2 (liver), SGC7901 (stomach), K562 (leukemia), and HL60 (leukemia) cancer cell lines. Compound 20 exhibited potent cytotoxicity against HepG2 and SGC7901 cancer cells with the IC50 values of 6.9 and 6.9 µm, respectively.


Sujet(s)
Antinéoplasiques d'origine végétale/pharmacologie , Fruit/composition chimique , Melia azedarach/composition chimique , Triterpènes/pharmacologie , Antinéoplasiques d'origine végétale/composition chimique , Antinéoplasiques d'origine végétale/isolement et purification , Lignée cellulaire tumorale , Prolifération cellulaire/effets des médicaments et des substances chimiques , Survie cellulaire/effets des médicaments et des substances chimiques , Relation dose-effet des médicaments , Tests de criblage d'agents antitumoraux , Humains , Conformation moléculaire , Relation structure-activité , Triterpènes/composition chimique , Triterpènes/isolement et purification
15.
Molecules ; 21(6)2016 Jun 11.
Article de Anglais | MEDLINE | ID: mdl-27294908

RÉSUMÉ

M01A82W, M11A82W and M01A82WS72I are three cytochrome P450 BM3 (CYP102A1) variants. They can catalyze the hydroxylation of testosterone (TES) and norethisterone at different positions, thereby making them promising biocatalysts for steroid hydroxylation. With the aim of obtaining more hydroxylated steroid precursors it is necessary to probe the steroidal substrate diversity of these BM3 variants. Here, three purified BM3 variants were first incubated with eight steroids, including testosterone (TES), methyltestosterone (MT), cholesterol, ß-sitosterol, dehydroepiandrosterone (DHEA), diosgenin, pregnenolone and ergosterol. The results indicated that the two 3-keto-Δ4-steroids TES and MT can be hydroxylated at various positions by the three BM3 mutants, respectively. On the contrary, the three enzymes displayed no any activity toward the remaining six 3-hydroxy-Δ5-steroids. This result indicates that the BM3 mutants prefer 3-keto-Δ4-steroids as hydroxylation substrates. To further verify this notion, five other substrates, including two 3-hydroxy-Δ5-steroids and three 3-keto-Δ4-steroids, were carefully selected to incubate with the three BM3 variants. The results indicated the three 3-keto-Δ4-steroids can be metabolized to form hydroxysteroids by the three BM3 variants. On the other hand, the two 3-hydroxy-Δ5-steroids cannot be hydroxylated at any position by the BM3 mutants. These results further support the above conclusion, therefore demonstrating the 3-keto-Δ4-steroid substrate preference of BM3 mutants, and laying a foundation for microbial production of more hydroxylated steroid intermediates using BM3 variants.


Sujet(s)
Bactéries/métabolisme , Famille-1 de cytochromes P450/métabolisme , Enzymes/métabolisme , Stéroïdes/métabolisme , Bactéries/composition chimique , Bactéries/génétique , Famille-1 de cytochromes P450/composition chimique , Famille-1 de cytochromes P450/génétique , Enzymes/composition chimique , Enzymes/génétique , Hydroxylation , Mutation , Noréthistérone/composition chimique , Noréthistérone/métabolisme , Oxydoréduction , Stéroïdes/composition chimique , Spécificité du substrat , Testostérone/composition chimique , Testostérone/métabolisme
16.
J Ultrasound Med ; 35(3): 581-7, 2016 Mar.
Article de Anglais | MEDLINE | ID: mdl-26887448

RÉSUMÉ

OBJECTIVES: To perform an in vitro experimental study of the possible damage effects on Bacille Calmette-Guérin (BCG) by low-frequency (42-kHz) ultrasound (US) irradiation at low spatially and temporally averaged intensities and different exposure times. METHODS: A 2-mL BCG suspension was added to the wells of a 24-well cell culture plate. Then the samples were randomly divided into 4 groups, each group including 3 wells, with group 1 as a control group and groups 2, 3, and 4, as US treatment groups. The samples for groups 2, 3, and 4 were irradiated with US at 0.13 W/cm(2) for 5 minutes, 0.13 W/cm(2) for 15 minutes, and 1.53 W/cm(2) for 15 minutes, respectively. After irradiation, the temperature, ratio of damage, and structure of the bacteria were examined. The cavitation effect of the device was detected by the passive cavitation detection method. RESULTS: After US irradiation at the different doses (intensity and exposure time), no significant temperature change was found in all sample suspensions. The ratio of bacterial damage tested by flow cytometry and the optical density of the suspensions as assayed by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide colorimetric method showed that the US-irradiated groups were significantly different from the control group. The BCG damage ratio reached 28% at the intensity of 1.53 W/cm(2). Transmission electron microscopic results showed that the bacterial structure of BCG could be destroyed by low-frequency, low-intensity US. CONCLUSIONS: Low-frequency, low-intensity US can cause acute injury to BCG, and the degree of injury is closely correlated with the US dose applied.


Sujet(s)
Mycobacterium bovis/physiologie , Mycobacterium bovis/ultrastructure , Ultrasonothérapie/méthodes , Ondes ultrasonores , Relation dose-effet des rayonnements , Femelle , Humains , Mâle , Mycobacterium bovis/effets des radiations , Projets pilotes , Dose de rayonnement , Résultat thérapeutique
17.
Oncotarget ; 6(35): 37626-37, 2015 Nov 10.
Article de Anglais | MEDLINE | ID: mdl-26485753

RÉSUMÉ

HIFU has been demonstrated to enhance anti-tumor immunity, however, the mechanism of which has not been well elucidated. Emerging evidence indicates that miRNAs play important roles in immune response. In this study, we used the B16F10 melanoma allograft mouse model to investigate the role of miRNAs in HIFU-enhanced anti-tumor immunity. We found that HIFU treatment decreased circulating B16F10 cells and pulmonary metastasis nodules while increased IFN-γ and TNF-α in the peripheral blood and cumulative mouse survival, which was associated with inhibition of miR-134 expression and activation of CD86 expression in tumor tissues. Further, we determined that miR-134 directly binds to the 3'UTR of CD86 mRNA to suppress its expression in B16F10 cells. When B16F10 cells transfected with miR-134 were co-cultured with normal splenic lymphocytes, the secretion of IFN-γ and TNF-α from lymphocytes was reduced and B16F10 cell survival was increased. HIFU exposure efficiently decreased miR-134 while increased CD86 expression in B16F10 cells in vitro. CD86 knockdown with siRNA markedly rescued the viability of HIFU-treated B16F10 cells that co-cultured with lymphocytes. Altogether, our results suggest that HIFU down-regulates miR-134 to release the inhibition of miR-134 on CD86 in melanoma cells, thereby enhancing anti-tumor immune response.


Sujet(s)
Antigène CD86/antagonistes et inhibiteurs , Tumeurs du poumon/immunologie , Mélanome expérimental/immunologie , microARN/génétique , Ultrasonothérapie , Animaux , Apoptose/génétique , Apoptose/effets des radiations , Antigène CD86/génétique , Antigène CD86/métabolisme , Technique de Western , Prolifération cellulaire/génétique , Prolifération cellulaire/effets des radiations , Femelle , Cytométrie en flux , Humains , Tumeurs du poumon/imagerie diagnostique , Tumeurs du poumon/génétique , Tumeurs du poumon/secondaire , Mélanome expérimental/imagerie diagnostique , Mélanome expérimental/génétique , Mélanome expérimental/anatomopathologie , Souris , Souris de lignée C57BL , ARN messager/génétique , Réaction de polymérisation en chaine en temps réel , RT-PCR , Cellules cancéreuses en culture , Échographie , Tests d'activité antitumorale sur modèle de xénogreffe
18.
Molecules ; 19(2): 1608-21, 2014 Jan 28.
Article de Anglais | MEDLINE | ID: mdl-24476601

RÉSUMÉ

OSW-1, isolated from the bulbs of Ornithogalum saundersiae Baker, is a steroidal saponin endowed with considerable antitumor properties. Biosynthesis of the 4-methoxybenzoyl group on the disaccharide moiety of OSW-1 is known to take place biochemically via the phenylpropanoid biosynthetic pathway, but molecular biological characterization of the related genes has been insufficient. Cinnamic acid 4-hydroxylase (C4H, EC 1.14.13.11), catalyzing the hydroxylation of trans-cinnamic acid to p-coumaric acid, plays a key role in the ability of phenylpropanoid metabolism to channel carbon to produce the 4-methoxybenzoyl group on the disaccharide moiety of OSW-1. Molecular isolation and functional characterization of the C4H genes, therefore, is an important step for pathway characterization of 4-methoxybenzoyl group biosynthesis. In this study, a gene coding for C4H, designated as OsaC4H, was isolated according to the transcriptome sequencing results of Ornithogalum saundersiae. The full-length OsaC4H cDNA is 1,608-bp long, with a 1,518-bp open reading frame encoding a protein of 505 amino acids, a 55-bp 5' non-coding region and a 35-bp 3'-untranslated region. OsaC4H was functionally characterized by expression in Saccharomyces cerevisiae and shown to catalyze the oxidation of trans-cinnamic acid to p-coumaric acid, which was identified by high performance liquid chromatography with diode array detection (HPLC-DAD), HPLC-MS and nuclear magnetic resonance (NMR) analysis. The identification of the OsaC4H gene was expected to open the way to clarification of the biosynthetic pathway of OSW-1.


Sujet(s)
Clonage moléculaire , Ornithogalum/enzymologie , Saponines/biosynthèse , Trans-cinnamate 4-monooxygenase/génétique , Cholesténones/composition chimique , Cholesténones/isolement et purification , Cinnamates/composition chimique , ADN complémentaire/génétique , Régulation de l'expression des gènes végétaux , Hydroxylation , Racines de plante/enzymologie , Saccharomyces cerevisiae/génétique , Saponines/composition chimique , Saponines/isolement et purification , Trans-cinnamate 4-monooxygenase/biosynthèse , Trans-cinnamate 4-monooxygenase/isolement et purification
19.
Abdom Imaging ; 38(6): 1263-8, 2013 Dec.
Article de Anglais | MEDLINE | ID: mdl-23728304

RÉSUMÉ

PURPOSE: We evaluated the usefulness of color Doppler flow imaging to compensate for the inadequate resolution of the ultrasound (US) monitoring during high-intensity focused ultrasound (HIFU) for the treatment of hepatocellular carcinoma (HCC). MATERIALS AND METHODS: US-guided HIFU ablation assisted using color Doppler flow imaging was performed in 11 patients with small HCC (<3 lesions, <3 cm in diameter). The HIFU system (Chongqing Haifu Tech) was used under US guidance. Color Doppler sonographic studies were performed using an HIFU 6150S US imaging unit system and a 2.7-MHz electronic convex probe. RESULTS: The color Doppler images were used because of the influence of multi-reflections and the emergence of hyperecho. In 1 of the 11 patients, multi-reflections were responsible for the poor visualization of the tumor. In 10 cases, the tumor was poorly visualized because of the emergence of a hyperecho. In these cases, the ability to identify the original tumor location on the monitor by referencing the color Doppler images of the portal vein and the hepatic vein was very useful. HIFU treatments were successfully performed in all 11 patients with the assistance of color Doppler imaging. CONCLUSION: Color Doppler imaging is useful for the treatment of HCC using HIFU, compensating for the occasionally poor visualization provided by B-mode conventional US imaging.


Sujet(s)
Carcinome hépatocellulaire/chirurgie , Ablation par ultrasons focalisés de haute intensité , Tumeurs du foie/chirurgie , Échographie-doppler couleur , Échographie interventionnelle , Sujet âgé , Sujet âgé de 80 ans ou plus , Carcinome hépatocellulaire/imagerie diagnostique , Femelle , Veines hépatiques/imagerie diagnostique , Humains , Tumeurs du foie/imagerie diagnostique , Mâle , Veine porte/imagerie diagnostique , Résultat thérapeutique
20.
Yao Xue Xue Bao ; 48(2): 228-35, 2013 Feb.
Article de Chinois | MEDLINE | ID: mdl-23672019

RÉSUMÉ

Synthetic biology of natural products is the design and construction of new biological systems by transferring a metabolic pathway of interest products into a chassis. Large-scale production of natural products is achieved by coordinate expression of multiple genes involved in genetic pathway of desired products. Promoters are cis-elements and play important roles in the balance of the metabolic pathways controlled by multiple genes by regulating gene expression. A detection plasmid of Saccharomyces cerevisiae was constructed based on DsRed-Monomer gene encoding for a red fluorescent protein. This plasmid was used for screening the efficient promoters applying for multiple gene-controlled pathways. First of all, eight pairs of primers specific to DsRed-Monomer gene were synthesized. The rapid cloning of DsRed-Monomer gene was performed based on step-by-step extension of a short region of the gene through a series of PCR reactions. All cloned sequences were confirmed by DNA sequencing. A vector named pEASYDs-M containing full-length DsRed-Monomer gene was constructed and was used as the template for the construction of S. cerevisiae expression vector named for pYeDP60-Ds-M. pYeDP60-Ds-M was then transformed into S. cerevisiae for heterologous expression of DsRed-Monomer gene. SDS-PAGE, Western blot and fluorescence microscopy results showed that the recombinant DsRed-Monomer protein was expressed successfully in S. cerevisiae. The well-characterized DsRed-Monomer gene was then cloned into a yeast expression vector pGBT9 to obtain a promoter detection plasmid pGBT9Red. For determination efficacy of pGBT9Red, six promoters (including four inducible promoters and two constitutive promoters) were cloned by PCR from the S. cerevisiae genome, and cloned into pGBT9Red by placing upstream of DsRed-Monomer gene, separately. The fluorescence microscopy results indicated that the six promoters (GAL1, GAL2, GAL7, GAL10, TEF2 and PGK1) can regulate the expression of DsRed-Monomer gene. The successful construction of pGBT9Red lays the foundation for further analysis of promoter activity and screening of promoter element libraries.


Sujet(s)
Protéines luminescentes/génétique , Plasmides/génétique , Régions promotrices (génétique)/génétique , Saccharomyces cerevisiae/génétique , Biologie synthétique , Séquence d'acides aminés , Séquence nucléotidique/génétique , Clonage moléculaire , Amorces ADN/biosynthèse , Régulation de l'expression des gènes fongiques , Vecteurs génétiques , Protéines luminescentes/métabolisme , Protéines recombinantes/biosynthèse , Protéines recombinantes/génétique , Saccharomyces cerevisiae/métabolisme , Transformation génétique ,
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