Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 18 de 18
Filtrar
Más filtros

Bases de datos
País/Región como asunto
Tipo del documento
País de afiliación
Intervalo de año de publicación
1.
Opt Lett ; 48(15): 3845-3848, 2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37527064

RESUMEN

A novel high-sensitivity temperature sensor based on a chirped thin-core fiber Bragg grating Fabry-Perot interferometer (CTFBG-FPI) and the Vernier effect is proposed and demonstrated. With femtosecond laser direct writing technology, two CTFBG-FPIs with different interferometric cavity lengths are inscribed inside a thin-core fiber to form a Vernier effect system. The two FPIs consist of two pairs of CTFBGs with a full width at half maximum (FWHM) of 66.5 nm staggered in parallel. The interferometric cavity lengths of the two FPIs were designed to be 2 mm and 1.98 mm as the reference arm and sensing arm of the sensor, respectively. The temperature sensitivity of this sensor was measured to be -1.084 nm/°C in a range of 40-90°C. This sensor is expected to play a crucial role in precision temperature measurement applications.

2.
Opt Lett ; 46(9): 2059-2062, 2021 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-33929418

RESUMEN

In this work, a method is proposed and demonstrated for fabrication of chirped fiber Bragg gratings (CFBGs) in single-mode fiber by femtosecond laser point-by-point inscription. CFBGs with bandwidths from 2 to 12 nm and dispersion ranges from 14.2 to 85 ps/nm are designed and achieved. The sensitivities of temperature and strain are 14.91 pm/°C and 1.21pm/µÎµ, respectively. Compared to the present phase mask method, femtosecond laser point-by-point inscription technology has the advantage of manufacturing CFBGs with different parameter flexibilities, and is expected to be widely applied in the future.

3.
Hepatobiliary Pancreat Dis Int ; 14(3): 236-45, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26063023

RESUMEN

BACKGROUND: Hepatocellular carcinoma (HCC) is one of the most common tumors worldwide and liver transplantation (LT) is considered as the best therapeutic option for patients with HCC combined with cirrhosis. However, tumor recurrence after LT for HCC remains the major obstacle for long-term survival. The present study was to evaluate the efficacy and necessity of adjuvant chemotherapy in patients with HCC who had undergone LT. DATA SOURCES: Several databases were searched to identify comparative studies fulfilling the predefined selection criteria before October 2014. Suitable studies were chosen and data extracted for meta-analysis. Three authors independently evaluated the bias of each study according to the Cochrane Handbook for Systematic Review of Intervention. Stata 12 was used for statistical analysis. Hazard ratio (HR) was considered as a summary statistic for overall survival, disease-free survival and recurrence rate. RESULTS: Three prospective studies and 5 retrospective studies including 360 patients (166 in the adjuvant chemotherapy group, and 194 in the control group) were included. Compared with the control group, post-LT adjuvant chemotherapy conferred significant benefit for overall survival (HR: 0.34; 95% CI: 0.22-0.52; P=0.000). Meanwhile, the results showed an improvement for disease-free survival on favoring adjuvant chemotherapy (HR: 0.87; 95% CI: 0.78-0.95; P=0.004). However, no significant difference in HCC recurrence rate was observed between the two groups (HR: 1.26; 95% CI: 0.40-4.00; P=0.696). Descriptions of adverse events were of anecdotal nature and did not allow meta-analytic calculations. CONCLUSIONS: Adjuvant chemotherapy after LT for HCC can significantly prolong patient's survival and delay the recurrence of HCC. For advanced HCC with poor differentiation, patients may perhaps benefit from the early implantation of adjuvant chemotherapy after LT.


Asunto(s)
Carcinoma Hepatocelular/terapia , Neoplasias Hepáticas/terapia , Trasplante de Hígado , Adulto , Anciano , Carcinoma Hepatocelular/mortalidad , Carcinoma Hepatocelular/patología , Quimioterapia Adyuvante , Distribución de Chi-Cuadrado , Progresión de la Enfermedad , Supervivencia sin Enfermedad , Femenino , Humanos , Neoplasias Hepáticas/mortalidad , Neoplasias Hepáticas/patología , Trasplante de Hígado/efectos adversos , Trasplante de Hígado/mortalidad , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia , Oportunidad Relativa , Selección de Paciente , Medición de Riesgo , Factores de Riesgo , Análisis de Supervivencia , Factores de Tiempo , Resultado del Tratamiento
4.
Beilstein J Org Chem ; 10: 858-862, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24778741

RESUMEN

Two pairs of geometrical isomers - cuevaenes A (1) and C (3) as well as cuevaenes D (4) and E (5) - and cuevaene B (2) were isolated from gdmAI-disrupted Streptomyces sp. LZ35. The constitution of cuevaene C (3) was found to be identical to cuevaene A (1) by means of NMR spectroscopy and high resolution mass spectrometry. However, the relative configurations of the triene side chain moieties were determined to be different. It was established on the basis of spectroscopic data that cuevaenes D (4) and E (5) are amides and geometrical isomers. Cuevaenes A-C (1-3) displayed moderate activity against Gram-positive bacteria (e.g., Bacillus subtilis strain ATCC 11060) and modest activity against fungi (e.g., Fusarium verticillioides strain S68 and Rhizoctonia solani strain GXE4). However, cuevaenes D (4) and E (5) showed no inhibitory activity against any of the tested microbes.

5.
Heliyon ; 10(12): e32658, 2024 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-38948048

RESUMEN

Deformation control of deep roadways is a major challenge for mine safety production. Taking a deep roadway with a burial depth of 965 m in a mine in North China as the engineering background, on-site investigation found that significant creep deformation occurred in the surrounding rock of the roadway. The original supporting U-shaped steel support failed due to insufficient supporting strength. The rock mass near the roadway experienced a transition from triaxial stress conditions to biaxial and even uniaxial stress states as a result of excavation and unloading, leading to a gradient stress distribution in the surrounding rock. From the perspective of the roadway's deviatoric stress field distribution, we investigated the gradient failure mechanism of the roadway and validated it through theoretical analysis and numerical simulations. The study found that the ratio of horizontal principal stress and vertical principal stress determines the distribution shape of the surrounding rock deviatoric stress field. The gradient distribution of the stress field in the roadway will cause time-related deformation of the roadway, which will lead to large deformation and failure of the roadway. Based on this, the control mechanism of roadway gradient failure was studied, and then a combined support technology of CFST supports with high bearing capacity was proposed.

6.
Life (Basel) ; 14(5)2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38792616

RESUMEN

Soil salinization poses a threat to the sustainability of agricultural production and has become a global issue. Cotton is an important cash crop and plays an important role in economic development. Salt stress has been harming the yield and quality of many crops, including cotton, for many years. In recent years, soil salinization has been increasing. It is crucial to study the mechanism of cotton salt tolerance and explore diversified materials and methods to alleviate the salt stress of cotton for the development of the cotton industry. Nanoparticles (NPs) are an effective means to alleviate salt stress. In this study, zinc oxide NPs (ZnO NPs) were sprayed on cotton leaves with the aim of investigating the intrinsic mechanism of NPs to alleviate salt stress in cotton. The results show that the foliar spraying of ZnO NPs significantly alleviated the negative effects of salt stress on hydroponic cotton seedlings, including the improvement of above-ground and root dry and fresh weight, leaf area, seedling height, and stem diameter. In addition, ZnO NPs can significantly improve the salt-induced oxidative stress by reducing the levels of MDA, H2O2, and O2- and increasing the activities of major antioxidant enzymes, such as superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT). Furthermore, RNA-seq showed that the foliar spraying of ZnO NPs could induce the expressions of CNGC, NHX2, AHA3, HAK17, and other genes, and reduce the expression of SKOR, combined with the CBL-CIPK pathway, which alleviated the toxic effect of excessive Na+ and reduced the loss of excessive K+ so that the Na+/K+ ratio was stabilized. In summary, our results indicate that the foliar application of ZnO NPs can alleviate high salt stress in cotton by adjusting the Na+/K+ ratio and regulating antioxidative ability. This provides a new strategy for alleviating the salt stress of cotton and other crops, which is conducive to the development of agriculture.

7.
Eur J Orthop Surg Traumatol ; 23 Suppl 1: S59-66, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23412310

RESUMEN

The aim of this study was to retrospectively analyze and evaluate the effect of treatment employing pedicle subtraction osteotomy for chronic, posttraumatic thoracolumbar kyphosis. This study included 19 patients, 11 males and 8 females, with chronic, posttraumatic thoracolumbar kyphosis. Pre-operative kyphosis ranged from 31° to 63°. The history of trauma ranged from 8 to 63 months. All patients were treated with pedicle subtraction osteotomy. A mean 40.2° improvement in sagittal alignment was achieved with a mean correction rate of 85.8 %. Perioperative complications were encountered in two patients, one with cerebrospinal fluid leakage followed by encephalitic infection and one with a wound infection. Both were treated conservatively with antibiotics and local wound care. There were no other severe complications. The average follow-up period was 15 months (range 6-41 months). At the last follow-up, clinical symptoms and neurological function were significantly improved. Of 14 patients presenting with intractable back pain, VAS scores improved from a preoperative mean of 6.7 (range 5.0-8.0) to an average 2.0 (range 0-3.0) at final follow-up. No significant loss of correction was observed (loss of 1.7°), and solid fusion was achieved in all 19 patients. A single-stage posterior pedicle subtraction osteotomy is a safe and effective procedure for correction of posttraumatic thoracolumbar kyphosis. Using this technique, it is possible to safely obtain no greater than 55° of correction at a single level.


Asunto(s)
Cifosis , Vértebras Lumbares , Osteotomía , Complicaciones Posoperatorias/diagnóstico , Traumatismos Vertebrales/complicaciones , Vértebras Torácicas , Adulto , China , Investigación sobre la Eficacia Comparativa , Femenino , Humanos , Cifosis/diagnóstico , Cifosis/etiología , Cifosis/fisiopatología , Cifosis/cirugía , Vértebras Lumbares/lesiones , Vértebras Lumbares/cirugía , Masculino , Persona de Mediana Edad , Osteotomía/efectos adversos , Osteotomía/métodos , Dimensión del Dolor , Complicaciones Posoperatorias/fisiopatología , Complicaciones Posoperatorias/terapia , Recuperación de la Función , Estudios Retrospectivos , Vértebras Torácicas/lesiones , Vértebras Torácicas/cirugía , Resultado del Tratamiento
8.
Front Nutr ; 10: 1259929, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37850085

RESUMEN

Background: The pan-immune-inflammation value (PIV) has been reported as a promising prognostic biomarker in multiple cancers but still remains inconclusive. The objective of this study is to systematically investigate the association of the pretreatment PIV with survival outcomes in cancer patients, based on available literature. Methods: Online databases including PubMed, Embase and the Web of Science were thoroughly searched for studies evaluating the prognostic role of the pretreatment PIV in cancers from the inception to June 2023. Hazard ratios (HRs) with 95% confidence intervals (CIs) were always assessed using a random-effects model. Statistical analyses were performed using Stata 12.0. Results: Thirty studies were finally included after comprehensively study searching. In total, 8,799 cancer patients were enrolled in this meta-analysis. The pooled results demonstrated that patients in the high PIV group had a significantly poorer overall survival (HR = 2.07; 95%CI: 1.77-2.41; I2 = 73.0%) and progression-free survival (HR = 1.83; 95%CI: 1.37-2.45; I2 = 98.2%) than patients in the low PIV group. The prognostic significance of the PIV score on overall survival and progression-free survival was observed across various geographical regions, tumor stages and treatment strategies. Sensitivity analyses supported the stability of the above combined results. Conclusion: This meta-analysis demonstrated that the pretreatment PIV could be a non-invasive and efficacious prognostic biomarker for cancer patients.

9.
Am J Pathol ; 177(1): 141-52, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20489148

RESUMEN

Epithelial-mesenchymal transition is an important mechanism behind initiation of cancer invasion and metastasis. This study was performed to clarify the involvement of epithelial-mesenchymal transition in the progression of cholangiocarcinoma. Cholangiocarcinoma cell lines, CCKS-1 and TFK-1, were treated with transforming growth factor-beta1 (TGF-beta1), and the phenotypic changes and invasive activity were examined. Immunohistochemical analysis was performed using tissue sections of cholangiocarcinoma. In vitro, TGF-beta1 induced mesenchymal features in CCKS-1 and TFK-1 characterized by the reduction of E-cadherin and cytokeratin 19 expression and the induction of mesenchymal markers, such as vimentin and S100A4. TGF-beta1 also induced the nuclear expression of Snail, and the invasive activity was significantly increased in both cell lines. Studies using a mouse xenograft model showed that TGF-beta1 worsened the peritoneal dissemination of CCKS-1. All these changes by TGF-beta1 were inhibited by the simultaneous administration of soluble TGF-beta type II receptor. In vivo, six (16%) of 37 cholangiocarcinoma cases showed marked immunoreactivity of Snail in their nuclei. In these six cases, the immuno-expression of cytokeratin 19 was significantly reduced, and the expression of vimentin was significantly increased. The Snail expression significantly correlated with the lymph node metastasis and a poor survival rate of the patients. These results suggest that epithelial-mesenchymal transition induced by TGF-beta1/Snail activation is closely associated with the aggressive growth of cholangiocarcinoma, resulting in a poor prognosis.


Asunto(s)
Neoplasias de los Conductos Biliares , Conductos Biliares Intrahepáticos/patología , Colangiocarcinoma/metabolismo , Colangiocarcinoma/patología , Transición Epitelial-Mesenquimal/fisiología , Factores de Transcripción/metabolismo , Factor de Crecimiento Transformador beta1/metabolismo , Anciano , Animales , Neoplasias de los Conductos Biliares/metabolismo , Neoplasias de los Conductos Biliares/patología , Línea Celular Tumoral , Femenino , Humanos , Queratina-19/metabolismo , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Invasividad Neoplásica , Trasplante de Neoplasias , Fenotipo , Factores de Transcripción de la Familia Snail , Tasa de Supervivencia , Factores de Transcripción/genética , Trasplante Heterólogo
10.
Medicine (Baltimore) ; 100(38): e27151, 2021 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-34559104

RESUMEN

PURPOSE: This study aimed to assess the efficacy of traditional Chinese medicine (TCM) in septic patients treated with ulinastatin. METHODS: PubMed, EmBase, and the Cochrane library were searched up to January 2021 to identify randomized controlled trials. The weight mean difference (WMD) and relative risk (RR) with 95% confidence intervals were used with the random-effects model. RESULTS: Twenty-three randomized controlled trials with 1903 septic patients were included. TCM significantly reduced the APACHE II score (WMD: -5.18; P < .001), interleukin-6 (WMD: -63.00; P < .001), tumor necrosis factor-α (WMD: -8.86; P < .001), c-reactive protein (WMD: -9.47; P < .001), mechanical ventilation duration (WMD: -3.98; P < .001), intensive care unit stay (WMD: -4.18; P < .001), procalcitonin (WMD: -0.53; P < .001), lipopolysaccharide (WMD: -9.69; P < .001), B-type natriuretic peptide (WMD: -159.87; P < .001), creatine kinase isoenzyme MB (WMD: -45.67; P < .001), cardiac troponin I (WMD: -0.66; P < .001), and all-cause mortality risk (RR: 0.55; P < .001). CONCLUSIONS: TCM lowers inflammation levels and reduces the risk of all-cause mortality for septic patients.


Asunto(s)
Medicamentos Herbarios Chinos/uso terapéutico , Glicoproteínas/uso terapéutico , Sepsis/tratamiento farmacológico , Inhibidores de Tripsina/uso terapéutico , Medicamentos Herbarios Chinos/administración & dosificación , Glicoproteínas/administración & dosificación , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto , Resultado del Tratamiento , Inhibidores de Tripsina/administración & dosificación
11.
Reprod Biomed Online ; 19(5): 708-13, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20021719

RESUMEN

Vitrification is an effective method for the cryopreservation of mammalian embryos. Nevertheless, it is unclear which embryonic developmental stage is the most suited for vitrification and would ensure maximal developmental competence upon subsequent warming. This study, therefore, compared the effects of cryotop vitrification on the developmental competence of murine morula and blastocyst stage embryos. Additionally, trophectoderm (TE) and inner cell mass (ICM) cell numbers were compared in two hatched blastocyst groups derived from vitrified morulae and blastocysts, respectively. The post-vitrification survival rates for mouse embryos at the morula and blastocyst stage were 95.4% (186/195) and 96.5% (195/202), respectively. The blastocyst formation rate was significantly lower for vitrified morulae (90.3%) compared with the non-vitrified control group (98.4%) (P < 0.05). The hatching rates were similar between the vitrified morula (79.6%) and the vitrified blastocyst (81.0%) groups. When further development to the fully hatched blastocyst stage was compared, fully hatched blastocysts derived from vitrified morulae had significantly higher cell counts for both the ICM and TE lineage, as compared with hatched blastocysts derived from vitrified blastocysts (P < 0.001). Cryotop vitrification of mouse embryos at the morula stage rather than blastocyst stage would thus ensure a higher degree of post-warming developmental competence.


Asunto(s)
Blastocisto/citología , Criopreservación , Desarrollo Embrionario/fisiología , Mórula/citología , Animales , Técnicas de Cultivo de Embriones , Femenino , Masculino , Ratones , Ratones Endogámicos ICR
12.
J Cancer Res Ther ; 15(7): 1450-1463, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31939422

RESUMEN

Gastrectomy is considered the gold standard treatment for gastric cancer patients. Currently, there are two minimally invasive surgical methods to choose from, robotic gastrectomy (RG) and laparoscopic gastrectomy (LG). Nevertheless, it is still unclear which is superior between the two. This meta-analysis aimed to investigate the effectiveness and safety of RG and LG for gastric cancer. A systematic literature search was performed using PubMed, Embase, and the Cochrane Library databases until September 2018 in studies that compared RG and LG in gastric cancer patients. Operative and postoperative outcomes analyzed were assessed. The quality of the evidence was rated using the Grading of Recommendations, Assessment, Development and Evaluations. Twenty-four English studies were analyzed. The meta-analysis revealed that the RG group had a significantly longer operation time, lower intraoperative blood loss, and higher perioperative costs compared to the LG group. However, there were no differences in complications, conversion rate, reoperation rate, mortality, number of lymph nodes harvested, days of first flatus, postoperative hospitalization time, and survival rate between the two groups. RG was shown to be associated with decreased intraoperative blood loss and increased perioperative cost and operation time compared to LG. Several higher-quality original studies and prospective clinical trials are required to confirm the advantages of RG.


Asunto(s)
Gastrectomía , Laparoscopía , Procedimientos Quirúrgicos Robotizados , Neoplasias Gástricas/cirugía , Factores de Edad , Pérdida de Sangre Quirúrgica , Índice de Masa Corporal , Flatulencia , Gastrectomía/efectos adversos , Gastrectomía/métodos , Costos de la Atención en Salud , Humanos , Laparoscopía/efectos adversos , Laparoscopía/métodos , Tiempo de Internación , Tempo Operativo , Complicaciones Posoperatorias/etiología , Procedimientos Quirúrgicos Robotizados/efectos adversos , Procedimientos Quirúrgicos Robotizados/métodos , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/mortalidad , Resultado del Tratamiento
13.
J Cancer Res Ther ; 15(7): 1530-1534, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31939433

RESUMEN

OBJECTIVE: The purpose of this study was to investigate the rate and reasons and also the risk factors for unplanned reoperation after pancreatoduodenectomy (PD) in a single center. PATIENTS AND METHODS: This retrospective analysis included patients who underwent PD in the First Affiliated Hospital of Nanchang University between January 2010 and January 2018. The patients were divided into nonreoperation and reoperation groups according to whether they underwent unplanned reoperation following the primary PD. The incidence and reasons were examined. In addition, multivariate logistic regression analysis was performed to identify the risk factors for unplanned reoperation. RESULTS: Of the 330 patients who underwent PD operations, 22 (6.67%) underwent unplanned reoperation. The main reasons for reoperation were postpancreaticoduodenectomy hemorrhage (PPH) (12/22 [54.5%]) and pancreaticoenteric anastomotic (PEA) leak (5/22 [22.7%]). Multivariate logistic regression analyses identified that diabetes (odds ratio [OR], 3.70; 95% confidence interval [CI], 1.06-12.90; P = 0.04), intraoperative blood loss ≥400 mL (OR, 4.06; 95% CI, 1.29-12.84; P = 0.02), occurrence of postoperative complications in the form of PPH (OR, 30.67; 95% CI, 8.85-106.31; P < 0.001), and PEA leak (OR, 11.53; 95% CI, 3.03-43.98, P < 0.001) were independent risk factors for unplanned reoperation. CONCLUSIONS: Our results suggest that diabetes, intraoperative blood loss ≥400 mL, PPH, and PEA leak were independent risk factors for unplanned reoperation after primary PD.


Asunto(s)
Pancreaticoduodenectomía , Cuidados Posoperatorios , Reoperación , Anciano , Comorbilidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Pancreáticas/complicaciones , Neoplasias Pancreáticas/cirugía , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/cirugía , Reoperación/efectos adversos , Reoperación/métodos , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento
14.
Chin J Nat Med ; 14(12): 931-933, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28262120

RESUMEN

A new hexaketide acid esterified by the 17-hydroxyl group of 16,17-dihydroxycyclooctatin, namely 17-[16,17-dihydroxycyclooctatinyl]-hexaketide ester (1), a member of the group of rare bacterial diterpenes with a fused 5-8-5 ring system was isolated from strain Streptomyces sp. SR107. The structure was determined on the basis of its spectral data (1H NMR, 13C NMR, 1H-1H COSY, HSQC, HMBC, NOESY, IR and HR-ESI-MS). The antibacterial activity was also evaluated in this paper.


Asunto(s)
Antibacterianos/química , Antibacterianos/farmacología , Diterpenos/química , Diterpenos/farmacología , Streptomyces/química , Bacterias/efectos de los fármacos , Diterpenos/metabolismo , Ésteres/química , Ésteres/farmacología , Espectroscopía de Resonancia Magnética , Estructura Molecular
15.
Exp Ther Med ; 8(3): 1005-1009, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25120638

RESUMEN

In the present study, the effect of Aurora-B inhibition on HepG2 cell invasion and migration in vitro was investigated. A recombinant plasmid targeting the Aurora-B gene (MiR-Aurora-B) was used to inhibit Aurora-B expression in HepG2 cells. Cell migration and invasion were investigated using Transwell migration and invasion assays. The results demonstrated that cell invasion and migration were suppressed by inhibiting Aurora-B. In addition, the effect of Aurora-B inhibition on the activity of the phosphoinositide 3-kinase (PI3K)/Akt/nuclear factor (NF)-κB signaling pathway was investigated by analyzing the protein expression levels of phosphorylated (p)-Akt, Akt, NF-κB p65, matrix metalloproteinase (MMP)-2 and MMP-9 using western blot analysis. The results demonstrated that the protein expression levels of p-Akt, NF-κB p65, MMP-2 and MMP-9 were reduced significantly by inhibiting Aurora-B. Therefore, inhibition of Aurora-B was shown to suppress hepatocellular carcinoma cell migration and invasion by decreasing the activity of the PI3K/Akt/NF-κB signaling pathway in vitro.

16.
Gene ; 544(1): 93-9, 2014 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-24768719

RESUMEN

Divergolides are a group of structurally unprecedented ansamacrolactam antibiotics with antibacterial and antitumor activities. A biosynthetic gene cluster predicted to encode the biosynthesis of divergolides was cloned and sequenced from endophytic Streptomyces sp. W112. The gene cluster of divergolides (div) spans a DNA region of 61-kb and consists of 20 open reading frames (ORFs) that encode polyketide synthases (PKSs), enzymes for the synthesis of AHBA and PKS extender units, and post-PKS modifications, proposed regulators, and putative transporters. Disruption of the AHBA synthase gene (divK) completely abolished the production of divergolides proved its involvement in the biosynthesis of divergolides. Bioinformatics analysis suggested that the regulatory gene div8 in div gene cluster might encode a positive regulator for the biosynthesis of divergolides. Constitutive overexpression of div8 improved the production of divergolides E, implying that div gene cluster maybe responsible for the biosynthesis of divergolides. These findings set the stage for fully investigating the biosynthesis of divergolides and rational engineering of new divergolide analogs by genetic modifications, and pave the way to further improve the production of divergolides.


Asunto(s)
Proteínas Bacterianas/genética , Macrólidos/metabolismo , Familia de Multigenes , Streptomyces/genética , Aminobenzoatos/metabolismo , Antibacterianos/biosíntesis , Antibacterianos/química , Proteínas Bacterianas/metabolismo , Vías Biosintéticas/genética , Clonación Molecular , Regulación Bacteriana de la Expresión Génica , Biblioteca Genómica , Hidroliasas/genética , Hidroliasas/metabolismo , Hidroxibenzoatos/metabolismo , Macrólidos/química , Espectroscopía de Resonancia Magnética , Estructura Molecular , Sistemas de Lectura Abierta/genética , Sintasas Poliquetidas/genética , Sintasas Poliquetidas/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Análisis de Secuencia de ADN , Espectrometría de Masa por Ionización de Electrospray , Streptomyces/metabolismo
17.
J Ovarian Res ; 5(1): 27, 2012 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-23039212

RESUMEN

OBJECTIVES: This study sought to evaluate the outcome of fresh and vitrified-warmed cleavage-stage and blastocyst-stage embryo transfers in patients undergoing ART treatment within an ethnic Chinese population. STUDY DESIGN: We compared the clinical results of embryo transfer on the 3rd (cleavage stage) or 5th (blastocyst stage) day after oocyte retrieval, including clinical pregnancy rates, implantation rates and multiple pregnancy rates. RESULTS: Our data showed that blastocyst transfer on day 5 did not significantly increase clinical pregnancy rate (41.07% vs 47.08%, p>0.05) and implantation rate (31.8% vs 31.2%, p>0.05) in patients under 35 years of age, in comparison with day 3 cleavage stage embryo transfer. In patients older than 35 years of age, the clinical pregnancy rate after blastocyst transfer was slightly decreased compared with cleavage stage embryo transfer (33.33% vs 42.31%, p>0.05). Unexpectedly, It was found that vitrified-warmed blastocyst transfer resulted in significantly higher clinical pregnancy rate (56.8%) and implantation rate (47%) compared with fresh blastocyst transfer in controlled stimulation cycles (41.07% and 31.8%, respectively). For patients under 35 years of age, the cumulative clinical pregnancy rate combining fresh and vitrified-warmed blastocyst transfer cycles were significantly higher compared to just cleavage-stage embryo transfer (70.1% versus 51.8%, p<0.05). However, the cumulative multiple pregnancy rates showed no significant difference between the two groups. CONCLUSIONS: In an ethnic Chinese patient population, fresh blastocyst transfer does not significantly increase clinical pregnancy rate. However, subsequent vitrified-warmed blastocyst transfer in a non-controlled ovarian hyperstimulation cycle dramatically improves clinical outcomes. Therefore, blastocyst culture in tandem with vitrified-warmed blastocyst transfer is recommended as a favourable and promising protocol in human ART treatment, particularly for ethnic Chinese patients.

18.
Drug Dev Ind Pharm ; 31(6): 545-9, 2005 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16109627

RESUMEN

The protein binding characteristic of 2'-Benzoyloxycinnamaldehyde (BCA) was investigated, which has demonstrated a potent antitumor effect against several human solid tumor cell lines and in human tumor xenograft nude mice. Protein binding of BCA in human serum was 86 +/- 0.91% and the predominant binding protein of BCA was fatty-acid-free human serum albumin (HSA) (81 +/- 0.91%). The binding of BCA to HSA was outlined by one class, and Ka and n of BCA were 1.65 x 10(5) M(- 1) and 0.374, respectively. Displacement studies with fluorescence probes suggested that BCA mainly binds to site I on HSA, and BCA-induced enhancement in site II binding. The limited drug-drug interaction experiments suggested that BCA influences both site I and site II drug-HSA bindings via different mechanisms; a competitive displacement and a probable allosteric conformational change in HSA, respectively.


Asunto(s)
Acroleína/análogos & derivados , Benzoatos/metabolismo , Albúmina Sérica/metabolismo , Acroleína/química , Acroleína/metabolismo , Antiinflamatorios no Esteroideos/farmacología , Anticoagulantes/farmacología , Antineoplásicos/metabolismo , Benzoatos/química , Diazepam/farmacología , Relación Dosis-Respuesta a Droga , Moduladores del GABA/farmacología , Humanos , Inmunoglobulina G/sangre , Inmunoglobulina G/metabolismo , Cinética , Orosomucoide/metabolismo , Fenilbutazona/farmacología , Unión Proteica/efectos de los fármacos , Temperatura , Warfarina/farmacología
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA