Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 30
Filtrar
Más filtros










Intervalo de año de publicación
1.
J Clin Child Adolesc Psychol ; : 1-14, 2020 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-31914322

RESUMEN

Objective: We used latent class analysis (LCA) to examine the prevalence and characteristics of the Dysregulation Profile (DP) based on data from the Child Behavior Checklist for Ages 6-18. The DP comprises elevated scores on the Anxious/Depressed, Attention Problems, and Aggressive Behavior syndromes and thus reflects significant problems in self-regulation of mood, attention, and behavior.Method: We examined CBCL data for 56,666 children ages 6 to 16 in 29 societies, many of which are countries but some of which are not (e.g., Hong Kong, Puerto Rico). The 29 societies varied widely in race/ethnicity, religion, geographic location, political/economic system, and population size.Results: The various statistical indices for good LCA model fit, while not always consistent, supported a DP class in every society. The omnicultural mean probability of assignment to the DP class (mean of the societal means) was 93% (SD = 2.4%). Prevalence of the DP class ranged from 2% to 18% across societies, with an omnicultural mean prevalence of 9%. In every society, the DP class had significantly higher scores than the pooled non-DP classes on all three DP syndromes. The 8-syndrome T score profile for the DP class in many societies featured elevations on all eight CBCL syndromes.Conclusions: Although the same instrument, analytic procedures, and decision rules were used in these 29 samples, model fit, the number of classes, and the prevalence of the DP class varied across societies. High scores on the three DP syndromes often co-occurred with high scores on most other CBCL syndromes.

2.
Chin Med J (Engl) ; 2020 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-31996543

RESUMEN

BACKGROUND: In recent years, norepinephrine has attracted increasing attention for the management of maternal hypotension during elective cesarean section with spinal anesthesia. Intermittent bolus is a widely used administration paradigm for vasopressors in obstetric anesthesia in China. Thus, in this randomized, double-blinded study, we compared the efficacy and safety of equivalent bolus norepinephrine and phenylephrine for rescuing maternal post-spinal hypotension. METHODS: In a tertiary women's hospital in Nanjing, China, 102 women were allocated with computer derived randomized number to receive prophylactic 8 µg norepinephrine (group N; n = 52) or 100 µg phenylephrine (group P; n = 50) immediately post-spinal anesthesia, followed by an extra bolus of the same dosage until delivery whenever maternal systolic blood pressure became lower than 80% of the baseline. Our primary outcome was standardized maternal cardiac output (CO) reading from spinal anesthesia until delivery analyzed by a two-step method. Other hemodynamic parameters related to vasopressor efficacy and safety were considered as secondary outcomes. Maternal side effects and neonatal outcomes were collected as well. RESULTS: Compared to group P, women in group N had a higher CO (standardized CO 5.8 ±â€Š0.9 vs. 5.3 ±â€Š1.0 L/min, t = 2.37, P = 0.02) and stroke volume (SV, standardized SV 73.6 ±â€Š17.2 vs. 60.0 ±â€Š13.3 mL, t = 4.52, P < 0.001), and a lower total peripheral resistance (875 ±â€Š174 vs. 996 ±â€Š182 dyne·s/cm, t = 3.44, P < 0.001). Furthermore, the incidence of bradycardia was lower in group N than in group P (2% vs. 14%, P = 0.023), along with an overall higher standardized heart rate (78.8 ±â€Š11.6 vs. 75.0 ±â€Š7.3 beats/min, P = 0.049). Other hemodynamics, as well as maternal side effects and neonatal outcomes, were similar in two groups (P > 0.05). CONCLUSIONS: Compared to equivalent phenylephrine, intermittent bolus norepinephrine provides a greater CO for management of maternal hypotension during elective cesarean section with spinal anesthesia; however, no obvious maternal or neonatal clinical advantages were observed for norepinephrine.

3.
Medicine (Baltimore) ; 98(51): e18311, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31860981

RESUMEN

BACKGROUND: Studies have shown the efficacy of norepinephrine in the treatment of maternal hypotension during cesarean section by comparing it to treatment with phenylephrine. However, few studies have compared the efficacy of norepinephrine to ephedrine. METHODS: Ninety-seven women undergoing elective cesarean section were administered norepinephrine at 4 µg/minute (group N; n = 48) or ephedrine at 4 mg/minute (group E; n = 49) immediately postspinal anesthesia, with an on-off titration to maintain systolic blood pressure (SBP) at 80% to 120% of baseline. A rescue bolus of 8 µg norepinephrine was given whenever SBP reached the predefined lower limit. Our primary outcome was the incidence of tachycardia. Secondary outcomes included the incidence of bradycardia, hypertension, hypotension, severe hypotension, hypotensive episodes, number of rescue top-ups, hemodynamic performance error including median performance error (MDPE), and median absolute performance error (MDAPE). Neonatal Apgar scores and umbilical arterial (UA) blood gas data were also collected. RESULTS: Women in group N experienced fewer cases of tachycardia (4.2% vs 30.6%, P = .002, odds ratio: 0.11 [95% confidence interval, CI: 0.02-0.47]), a lower standardized heart rate (HR) (70.3 ±â€Š11 vs 75 ±â€Š11, P = .04, difference: 4.7 ±â€Š2.2 [95% CI: 0.24-9.1]), and a lower MDPE for HR (1.3 ±â€Š9.6 vs 8.4 ±â€Š13.5 bpm, P = .003, difference: 3.1 ±â€Š1.8 [95% CI: -0.6-6.7]). In addition, the lowest or the highest HR was lower in group N compared to group E (both P < .05). Meanwhile, the standardized SBP in group N was lower than that in group E (P = .04). For neonates, the UA blood gas showed a higher base excess (BE) and a lower lactate level in group N compared to E (both P < .001). Other hemodynamic variables, maternal, and neonatal outcomes were similar. CONCLUSION: Infusion of 4 µg/minute norepinephrine presented fewer cases of tachycardia, less fluctuation and a lower HR compared to baseline values, as well as a less stressed fetal status compared to ephedrine infusion at 4 mg/minute. In addition, norepinephrine infusion presented a lower standardized SBP compared to ephedrine.


Asunto(s)
Anestesia Raquidea/métodos , Cesárea/efectos adversos , Efedrina/uso terapéutico , Hipotensión/prevención & control , Norepinefrina/uso terapéutico , Adulto , Anestesia Raquidea/efectos adversos , Presión Sanguínea/efectos de los fármacos , Cesárea/métodos , Método Doble Ciego , Efedrina/efectos adversos , Femenino , Frecuencia Cardíaca/efectos de los fármacos , Humanos , Hipotensión/etiología , Infusiones Intravenosas , Norepinefrina/administración & dosificación , Embarazo
4.
Biosci Rep ; 39(12)2019 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-31661545

RESUMEN

Delta-like homolog 1 (DLK1) regulates noncanonical Notch signaling pathway as ligand. DLK1 was abnormally expressed in a variety of tumors, affecting tumorigenesis and developments. The biological function of DLK1 toward cell proliferation and signaling activation was controversial across different cell types. Two currently known isoforms of DLK1, which are membrane-tethered isoform and soluble isoform, are believed to be the key of DLK1 dual behaviors. While these isoforms are not enough to explain the phenomena, our observations offer the possibility of a third isoform of DLK1. In the present study, we verified the nuclear localization of DLK1 in lung cancer cells. The nuclear localized DLK1 was observed in 107 of 351 non-small cell lung cancer (NSCLC) samples and was associated with tissue differentiation and tumor size. Through co-immunoprecipitation (co-IP) combined mass spectrometry (MS), we identified nuclear receptor corepressor 1 (NCOR1) as DLK1's novel interaction protein and confirmed their interaction in nuclear. We analyzed the expression of NCOR1 in two independent cohorts and demonstrated that NCOR1 is a tumor suppressor and has prognosis potential in lung squamous carcinomas. At last, we analyzed the colocalization of DLK1 and NCOR1 in 147 NSCLC samples by immunohistochemistry (IHC). The result indicated NCOR1 might participate with nuclear localized DLK1 in regulating cell differentiation.

5.
Multivariate Behav Res ; : 1-20, 2019 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-31165632

RESUMEN

A general modeling framework of response accuracy and response times is proposed to track skill acquisition and provide additional diagnostic information on the change of latent speed in a learning environment. This framework consists of two types of models: a dynamic response model that captures the response accuracy and the change of discrete latent attribute profile upon factors such as practice, intervention effects, and other latent and observable covariates, and a dynamic response time model that describes the change of the continuous response latency due to change of latent attribute profile. These two types of models are connected through a parameter, describing the change rate of the latent speed through the learning process, and a covariate defined as a function of the latent attribute profile. A Bayesian estimation procedure is developed to calibrate the model parameters and measure the latent variables. The estimation algorithm is evaluated through several simulation studies under various conditions. The proposed models are applied to a real data set collected through a spatial rotation diagnostic assessment paired with learning tools.

6.
Analyst ; 144(14): 4241-4249, 2019 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-31210200

RESUMEN

Development of a reliable and facile telomerase activity assay with high specificity and sensitivity is a central challenge to make telomerase testing a routine part of medical care with respect to cancer. Herein, we propose a point-of-care (POC) assay of telomerase activity based on multi-code magnetic beads initiated by DNAzyme-mediated double-cycling amplification coupling with a glucometer. A designed DNAzyme-based telomerase substrate prime (DTSP) probe consists of three regions (AXB) for a DNAzyme catalytic sequence, poly-thymine (poly-T) linker and telomere primer sequence. In the presence of telomerase, telomerase elongates the primer site on the DTSP probe. Subsequent addition of the PbII cofactor activates the DNAzyme, which cleaves the elongated fragment at the RNA site, and releases the DTSP probe for repetitive cycling and the elongated fragment. The cleaved fragment as a trigger then continuously triggers the cyclic strand displacement reaction (CSDR) between MB-H1 and invertase-H2, constructing the second cycling and forming the MB-H1/invertase-H2 duplex. Owing to the double-cycling amplification, numerous invertases were coded onto the surface of MBs. After magnetic separation, the enriched multi-code MB catalytically hydrolyzes the sucrose substrate with multiple turnovers, generating a large amount of glucose for quantitative readout by personal glucose meters (PGM). Benefiting from the double-cycling amplification and magnetic separation, a high signal-to-background ratio was achieved, and the point-of-care assay realizes sensitive telomerase activity detection down to 5 HeLa cells with a significantly enhanced dynamic range without the need for enzymatic amplification. The designed DTSP probe highly ensured the specificity and reliability due to the high dependence of DNAzyme on the metal ion cofactor. Moreover, this method can be applied for the screening of telomerase inhibitors and the discrimination of cancer cells from normal cells. With the ability of simple operation, outstanding sensitivity, and excellent selectivity, this method offers a convenient and specific POCT strategy for telomerase activity detection, holding great potential in clinical diagnosis and drug discovery.


Asunto(s)
Técnicas Biosensibles/métodos , Pruebas de Enzimas/métodos , Telomerasa/análisis , Línea Celular Tumoral , Sondas de ADN/química , Sondas de ADN/genética , ADN Catalítico/química , ADN Catalítico/genética , Glucosa/análisis , Humanos , Plomo/química , Fenómenos Magnéticos , Técnicas de Amplificación de Ácido Nucleico/métodos , Pruebas en el Punto de Atención , Saccharomyces cerevisiae/enzimología , Sacarosa/química , Telomerasa/química , beta-Fructofuranosidasa/química
7.
Bioresour Technol ; 288: 121526, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31129518

RESUMEN

A feruloyl esterase producing strain was isolated and identified as Lactobacillus crispatus S524. Its putative feruloyl esterase was heterogeneously expressed in Escherichia coli BL21 (DE3). Interestingly, the feruloyl esterase (FaeLcr) could be secreted into the culture medium with a relative high purity of 201.7 mg/L. FaeLcr was purified from the cell-free culture supernatant and appeared as a single protein band with the molecular mass of 28 kDa by SDS-PAGE. The optimal temperature and pH were determined as 65 °C and 7.0, and it showed prominent thermo-stability and alkali-stability. Furthermore, the purified FarLcr could release a maximal amount of 199 µg ferulic acid from 0.2 g de-starched wheat bran. Meanwhile, when cultured this recombinant E. coli strain in medium supplemented with 2 g de-starched wheat bran, 1.86 mg ferulic acid was also detected. These results suggested that the recombinant strain has a great potential application in feruloyl esterase and ferulic acid production.


Asunto(s)
Escherichia coli , Lactobacillus crispatus , Hidrolasas de Éster Carboxílico , Ácidos Cumáricos
8.
Behav Res Methods ; 2019 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-31065938

RESUMEN

Students who wish to learn a specific skill have increasing access to a growing number of online courses and open-source educational repositories of instructional tools, including videos, slides, and exercises. Navigating these tools is time-consuming and the search itself can hinder the learning of the skill. Educators are hence interested in aiding students by selecting the optimal content sequence for individual learners, specifically which skill one should learn next and which material one should use to study. Such adaptive selection would rely on pre-knowledge of how the learners' and the instructional tools' characteristics jointly affect the probability of acquiring a certain skill. Building upon previous research on Latent Transition Analysis and Learning Trajectories, we propose a multilevel logistic hidden Markov model for learning based on cognitive diagnosis models, where the probability that a learner acquires the target skill depends not only on the general difficulty of the skill and the learner's mastery of other skills in the curriculum but also on the effectiveness of the particular learning tool and its interaction with mastery of other skills, captured by random slopes and intercepts for each learning tool. A Bayesian modeling framework and an MCMC algorithm for parameter estimation are proposed and evaluated using a simulation study.

9.
Acta Cir Bras ; 34(4): e201900401, 2019 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-31066785

RESUMEN

PURPOSE: To investigate the relations of neuropeptide Y (NPY) and heme oxygenase-1 (HO-1) expressions with fetal brain injury in rats with intrahepatic cholestasis of pregnancy (ICP). METHODS: Sixty rats pregnant for 15 days were randomly divided into experimental and control groups. The ICP model was established in experimental group. On the 21st day, the blood biochemical test, histopathological examination of pregnant rat liver and fetal brain tissues and immunohistochemical analysis of fetal rat brain tissues were performed. RESULTS: On the 21st day, the alanineaminotransferase, aspartate aminotransferase and total bile acid levels in experimental group were significantly higher than control group (P<0.01). Compared with control group, there was obvious vacuolar degeneration in pregnant rat liver tissue and fetal brain tissue in experimental group. NPY expression in fetal brain tissue was negative in control group and positive in experimental group. HO-1 expression in fetal brain tissue was strongly positive in control group and positive in experimental group. There was significant difference of immunohistochemical staining optical density between two groups (P<0.01). CONCLUSION: In fetal brain of ICP rats, the NPY expression is increased, and the HO-1 expression is decreased, which may be related to the fetal brain injury.


Asunto(s)
Lesiones Encefálicas/metabolismo , Colestasis Intrahepática/metabolismo , Hemo-Oxigenasa 1/metabolismo , Neuropéptido Y/metabolismo , Complicaciones del Embarazo/metabolismo , Animales , Lesiones Encefálicas/etiología , Lesiones Encefálicas/patología , Colestasis Intrahepática/complicaciones , Colestasis Intrahepática/patología , Modelos Animales de Enfermedad , Femenino , Inmunohistoquímica , Embarazo , Complicaciones del Embarazo/patología , Ratas , Ratas Sprague-Dawley
10.
Appl Biochem Biotechnol ; 189(3): 822-833, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31127450

RESUMEN

It has been found that lactic acid and hydrogen peroxide (H2O2) displayed co-operatively enhanced killing activity to pathogens. The synergistic effect was investigated with using several microbe species, suggesting that low concentration of lactic acid and H2O2 could kill both Gram-negative and Gram-positive bacteria or even fungal pathogens. To explore the mechanism of synergistic sterilization of lactic acid and H2O2, Escherichia coli DH5α was used as the indicator bacteria. Lactic acid and H2O2 could generate hydroxyl radicals depending on the intracellular iron ions. The genomic DNA of treated cells was fractured and dispersed, and the △recA strain was more susceptive to the treatment, indicating that DNA damage was a cause of cell death. Furthermore, serious leakage of cell contents occurred in the treated cell, suggesting that the treatment also resulted in cell membrane permeability changes. This research shows that lactic acid-H2O2 consortium is a hopeful safety bactericide in agriculture or food production processes and provides a greater understanding of the mechanism of synergistic sterilization of lactic acid-H2O2 consortium in vivo.


Asunto(s)
Antibacterianos/farmacología , Peróxido de Hidrógeno/farmacología , Ácido Láctico/farmacología , Membrana Celular/efectos de los fármacos , Membrana Celular/metabolismo , Daño del ADN , Sinergismo Farmacológico , Escherichia coli/citología , Escherichia coli/efectos de los fármacos , Espacio Intracelular/efectos de los fármacos , Espacio Intracelular/metabolismo , Especies Reactivas de Oxígeno/metabolismo
11.
Jpn J Clin Oncol ; 49(7): 646-655, 2019 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-30968933

RESUMEN

BACKGROUND AND AIM: The impact of transarterial chemoembolization (TACE) and preventive antiviral therapy on the occurrence of hepatitis B virus (HBV) reactivation and subsequent hepatitis remains controversial. This meta-analysis aimed to evaluate the effect of TACE and preventive antiviral therapy on the risk of HBV reactivation and subsequent hepatitis. Meanwhile, we explored the role of HBeAg status in HBV reactivation after TACE. METHODS: We performed this meta-analysis with 11 included studies to assess the effect of TACE and preventive antiviral therapy on predicting clinical outcomes in HBV-related hepatocellular carcinoma (HCC). The pooled odds ratios (OR) were calculated using a random or fixed effects model. PUBMED, MEDLINE, EMBASE and the Cochrane Central Register of Controlled were searched for the included articles (from 2000 to December 2017). RESULTS: Our results showed that TACE significantly increased the risk of HBV reactivation (OR: 3.70; 95% CI 1.45-9.42; P < 0.01) and subsequent hepatitis (OR: 4.30; 95% CI 2.28-8.13; P < 0.01) in HCC patients. There was no significant difference in HBV reactivation after TACE between HBeAg positive and negative patients (OR: 1.28; 95% CI 0.31-5.34; P = 0.73). Preventive antiviral therapy could statistically reduce the rate of HBV reactivation (OR: 0.08; 95% CI 0.02-0.32; P < 0.01) and hepatitis (OR: 0.22; 95% CI 0.06-0.80; P = 0.02) in those with TACE treatment. CONCLUSIONS: The present study suggested that TACE was associated with a higher possibility of HBV reactivation and subsequent hepatitis. Preventive antiviral therapy is significantly in favor of a protective effect.


Asunto(s)
Antivirales/farmacología , Carcinoma Hepatocelular/terapia , Carcinoma Hepatocelular/virología , Quimioembolización Terapéutica , Virus de la Hepatitis B/efectos de los fármacos , Hepatitis B/prevención & control , Neoplasias Hepáticas/terapia , Activación Viral/efectos de los fármacos , Adulto , Anciano , Femenino , Estudios de Seguimiento , Humanos , Neoplasias Hepáticas/virología , Masculino , Persona de Mediana Edad , Pronóstico , Sesgo de Publicación , Factores de Riesgo
12.
J Biotechnol ; 295: 55-62, 2019 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-30853632

RESUMEN

Endoglucanase, an important component of cellulases, is used as additives in ensiling of forage crops. However, its detailed role is unclear in ensilages. In the present study, two endoglucanases Cel5 and Cel9 produced by strain Paenibacillus panacisoli SDMCC050309, previously isolated from ensiled corn stover, were identified in the cultures by microcrystalline cellulose absorption coupled with zymogram analysis. After heterologously expressed in Escherichia coli DE3 and purified, these two proteins were biochemically characterized. Cel5 was 61 kDa and showed maximal activity at pH 7.0 and 45 °C, while the maximum activity was at pH 8.0 and 65 °C for Cel9 with 97 kDa in size. Both of them could degrade carboxymethyl cellulose into cellooligosaccharides, in which cellobiose and cellotriose could be used as substrates for the growth of homofermentative strains Lactobacillus plantarum CGMCC6888 and L. farciminis CCTCC AB2016237, but not for the heterofermentative strains L. brevis SDMCC050297 and L. parafarraginis SDMCC050300. Therefore, we concluded that the added endoglucanase contributed to enhance the growth of homofermentative lactic acid bacteria for high level of lactic acid production in ensilages.


Asunto(s)
Celulasa/química , Celulasa/metabolismo , Lactobacillus/metabolismo , Ensilaje/microbiología , Proteínas Bacterianas/química , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Celulasa/genética , Celulosa/metabolismo , Estabilidad de Enzimas , Fermentación , Concentración de Iones de Hidrógeno , Oligosacáridos/metabolismo , Paenibacillus/enzimología , Paenibacillus/genética , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Temperatura Ambiental
13.
Acta cir. bras ; 34(4): e201900401, 2019. tab, graf
Artículo en Inglés | LILACS-Express | ID: biblio-1001090

RESUMEN

Abstract Purpose: To investigate the relations of neuropeptide Y (NPY) and heme oxygenase-1 (HO-1) expressions with fetal brain injury in rats with intrahepatic cholestasis of pregnancy (ICP). Methods: Sixty rats pregnant for 15 days were randomly divided into experimental and control groups. The ICP model was established in experimental group. On the 21st day, the blood biochemical test, histopathological examination of pregnant rat liver and fetal brain tissues and immunohistochemical analysis of fetal rat brain tissues were performed. Results: On the 21st day, the alanineaminotransferase, aspartate aminotransferase and total bile acid levels in experimental group were significantly higher than control group (P<0.01). Compared with control group, there was obvious vacuolar degeneration in pregnant rat liver tissue and fetal brain tissue in experimental group. NPY expression in fetal brain tissue was negative in control group and positive in experimental group. HO-1 expression in fetal brain tissue was strongly positive in control group and positive in experimental group. There was significant difference of immunohistochemical staining optical density between two groups (P<0.01). Conclusion: In fetal brain of ICP rats, the NPY expression is increased, and the HO-1 expression is decreased, which may be related to the fetal brain injury.

14.
Front Psychol ; 9: 2339, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30568609

RESUMEN

The increased popularity of computer-based testing has enabled researchers to collect various types of process data, including test takers' reaction time to assessment items, also known as response times. In recent studies, the relationship between speed and accuracy in a learning setting was explored to understand students' fluency changes over time in applying the mastered skills in addition to skill mastery. This can be achieved by modeling the changes in response accuracy and response times throughout the learning process. We propose a mixture learning model that utilizes the response times and response accuracy. Such a model accounts for the heterogeneities in learning styles among learners and may provide instructors with valuable information, which can be used to design individualized instructions. A Bayesian modeling framework is developed for parameter estimation and the proposed model is evaluated through a simulation study and is fitted to a real data set collected from a computer-based learning system for spatial rotation skills.

15.
J Cell Biochem ; 2018 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-30417424

RESUMEN

Inhibitors of the bromodomain and extraterminal domain family (BETi) offer a new approach to treat hematological malignancies, with leukemias containing mixed lineage leukemia rearrangements being especially sensitive due to a reliance on the regulation of transcription elongation. We explored the mechanism of action of BETi in cells expressing the t(8;21), and show that these compounds reduced the size of acute myeloid leukemia cells, triggered a rapid but reversible G0 /G1 arrest, and with time, cause cell death. Meta-analysis of PRO-seq data identified ribosomal genes, which are regulated by MYC, were downregulated within 3 hours of addition of the BETi. This reduction of MYC regulated metabolic genes coincided with the loss of mitochondrial respiration and large reductions in the glycolytic rate. In addition, gene expression analysis showed that transcription of BCL2 was rapidly affected by BETi but this did not cause dramatic increases in cell death. Cell cycle arrest, lowered metabolic activity, and reduced BCL2 levels suggested that a second compound was needed to push these cells over the apoptotic threshold. Indeed, low doses of the BCL2 inhibitor, venetoclax, in combination with the BETi was a potent combination in t(8;21) containing cells. Thus, BET inhibitors that affect MYC and BCL2 expression should be considered for combination therapy with venetoclax.

16.
Carbohydr Polym ; 184: 435-444, 2018 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-29352939

RESUMEN

The knowledge about the association of lignocellulosic biomass-degrading microbes with lactic acid bacteria (LAB) in ensilages is still limited. Paenibacillus strains are important microbes in sustainable agriculture. Here, P. panacisoli SDMCC050309 was isolated from ensiled corn stover and used as an example to investigate the effects on LAB. This strain produced at least 7 xylanases, and two of them were purified and characterized. Temperature and pH optima were determined to be 55 °C and 8.0 for Xyn10 and 40 °C and 7.0 for Xyn11, respectively. They could degraded larch wood xylan and alkali-pretreated corn stover into xylooligosaccharides (XOS). Using the produced XOS to culture Lactobacillus brevis SDMCC050297 and L. parafarraginis SDMCC050300, both of them grew well with high level of acetic acid production. The same phenomenon was observed when co-culturing those two Lactobacillus strains with P. panacisoli SDMCC050309. Therefore, P. panacisoli enhances growth of LAB by producing XOS in corn stover ensilages.


Asunto(s)
Glucuronatos/metabolismo , Oligosacáridos/metabolismo , Zea mays/química , Ácido Acético/metabolismo , Endo-1,4-beta Xilanasas/metabolismo , Lactobacillus brevis/fisiología , Paenibacillus/enzimología
17.
Sci Rep ; 7(1): 13614, 2017 10 19.
Artículo en Inglés | MEDLINE | ID: mdl-29051616

RESUMEN

To improve silage quality of crop forages, bacterial inoculants are often employed. In this study, Lactobacillus brevis SDMCC050297 and Lactobacillus parafarraginis SDMCC050300 were used as inoculants to corn stover in lab silos for ensiling. At the initial stage of ensiling, the pH value of the inoculated silages reduced more drastically, and the inoculated silages had higher lactic acid and acetic acid contents. After 20 days of ensiling, a reduction in lactic acid content coupled with an increase in acetic acid and 1,2-propanediol contents was observed in inoculated silages. Furthermore, both the amount of lactic acid bacteria and the abundance of order Lactobacillales in inoculated silages were higher than those of controls in the whole process. Meanwhile, Lb. brevis predominated before day 20 and then the dominance was shifted to Lb. parafarraginis until the late stage of ensiling. In contrast, the epiphytic Lactococcus lactic and Lb. plantarum played major roles at the beginning of naturally fermented silages and then Lb. plantarum and Lb. brevis were the most abundant at the later stage. In conclusion, these two selected strains had capability of improving the silage quality and providing the reproducible ensiling process, thus having the potential as silage inoculants.


Asunto(s)
Lactobacillus/crecimiento & desarrollo , Ensilaje/microbiología , Ácido Acético/metabolismo , Bacterias/genética , Bacterias/aislamiento & purificación , Reactores Biológicos , Concentración de Iones de Hidrógeno , Ácido Láctico/metabolismo , Lactobacillus/genética , Metagenómica , ARN Ribosómico 16S/química , ARN Ribosómico 16S/metabolismo , Análisis de Secuencia de ADN , Zea mays
18.
Front Microbiol ; 8: 941, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28626449

RESUMEN

Lactic acid bacteria (LAB) play important roles in silage fermentation, which depends on the production of sufficient organic acids to inhibit the growth of undesirable microorganisms. However, LAB are not able to degrade cellulose and hemicellulose. Bacteria and fibrolytic enzymes are usually used as inoculants to improve the silage quality and digestibility. In the present study, we isolated four Lactobacillus strains (L. amylovorus CGMCC 11056, L. acidophilus CCTCC AB2010208, L. farciminis CCTCC AB2016237 and L. fermentum CCTCC AB2010204) with feruloyl esterase (FAE) activities from ensiled corn stover (CS) by a plate screening assay. The genes encoding FAEs were cloned and hetero-expressed in Escherichia coli. The optimal temperature and pH of these purified enzymes ranged from 45 to 50°C and from 7.0 to 8.0, respectively. They could hydrolyze hydroxycinnamoyl esters in a substrate-specific manner when methyl ferulate, methyl caffeate, methyl ρ-coumarate and methyl sinapinate were used as substrates. Moreover, these four FAEs were able to hydrolyze CS to release hydroxycinnamic acids. Furthermore, these strains could degrade hydroxycinnamic esters, and L. amylovorus CGMCC 11056 was the most efficient strain among these four isolates. These results provided a new target for the development of inoculants to improve silage quality and digestibility.

19.
Curr Microbiol ; 74(6): 678-684, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28326449

RESUMEN

The twin-arginine translocation (Tat) system, which is used for folded protein secretion, is rare in lactic acid bacteria (LAB). Previously, a Tat system composed of TatAS and TatCS subunits (the subscript S denotes a Streptococcus thermophilus origin) was identified in S. thermophilus CGMCC 7.179. In the present study, the tatA S and tatC S genes were cloned and functionally analyzed in Escherichia coli DE3 tat-deficient mutants. The E. coli tatABCDE-deficient mutant complemented with tatC S A S exhibited shortened cellular chains, but its ability to grow in the presence of sodium dodecyl sulfate (SDS) was not restored, suggesting that the S. thermophilus Tat system could partially replace that of E. coli. Surprisingly, the E. coli tatABE-deficient mutant complemented with tatA S and the E. coli tatC-deficient mutant complemented with tatC S displayed relatively normal cellular morphology and enhanced tolerance to SDS. These results suggest that TatAS and TatCS could serve as active protein translocases in E. coli DE3 tat-deficient mutants. Moreover, TatAS acted as a bifunctional subunit to fulfill the roles of both TatA and TatB of E. coli DE3. Thus, this minimal Tat system would be a promising candidate to translocate recombinant proteins in LAB.


Asunto(s)
Proteínas Portadoras/genética , Escherichia coli/genética , Proteínas de Transporte de Membrana/genética , Transporte de Proteínas/genética , Streptococcus thermophilus/genética , Sistema de Translocación de Arginina Gemela/genética , Secuencia de Aminoácidos , Clonación Molecular , Escherichia coli/crecimiento & desarrollo , Escherichia coli/metabolismo , Eliminación de Gen , Prueba de Complementación Genética , Alineación de Secuencia , Dodecil Sulfato de Sodio/farmacología , Sistema de Translocación de Arginina Gemela/metabolismo
20.
Nat Commun ; 7: 13200, 2016 10 21.
Artículo en Inglés | MEDLINE | ID: mdl-27767028

RESUMEN

Multiple synchronous lung cancers (MSLCs) present a clinical dilemma as to whether individual tumours represent intrapulmonary metastases or independent tumours. In this study we analyse genomic profiles of 15 lung adenocarcinomas and one regional lymph node metastasis from 6 patients with MSLC. All 15 lung tumours demonstrate distinct genomic profiles, suggesting all are independent primary tumours, which are consistent with comprehensive histopathological assessment in 5 of the 6 patients. Lung tumours of the same individuals are no more similar to each other than are lung adenocarcinomas of different patients from TCGA cohort matched for tumour size and smoking status. Several known cancer-associated genes have different mutations in different tumours from the same patients. These findings suggest that in the context of identical constitutional genetic background and environmental exposure, different lung cancers in the same individual may have distinct genomic profiles and can be driven by distinct molecular events.


Asunto(s)
Adenocarcinoma/genética , Heterogeneidad Genética , Genoma Humano/genética , Neoplasias Pulmonares/genética , Adenocarcinoma/patología , Perfilación de la Expresión Génica/métodos , Regulación Neoplásica de la Expresión Génica , Humanos , Neoplasias Pulmonares/patología , Mutación , Análisis de Secuencia de ADN/métodos
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA