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1.
J Acoust Soc Am ; 156(1): 229-243, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38980098

RESUMEN

Koopman operator theory has gained interest as a framework for transforming nonlinear dynamics on the state space into linear dynamics on abstract function spaces, which preserves the underlying nonlinear dynamics of the system. These spaces can be approximated through data-driven methodologies, which enables the application of classical linear control strategies to nonlinear systems. Here, a Koopman linear quadratic regulator (KLQR) was used to acoustically control the nonlinear dynamics of a single spherical bubble, as described by the well-known Rayleigh-Plesset equation, with several objectives: (1) simple harmonic oscillation at amplitudes large enough to incite nonlinearities, (2) stabilization of the bubble at a nonequilibrium radius, and (3) periodic and quasiperiodic oscillation with multiple frequency components of arbitrary amplitude. The results demonstrate that the KLQR controller can effectively drive a spherical bubble to radially oscillate according to prescribed trajectories using both broadband and single-frequency acoustic driving. This approach has several advantages over previous efforts to acoustically control bubbles, including the ability to track arbitrary trajectories, robustness, and the use of linear control methods, which do not depend on initial guesses.

2.
Beijing Da Xue Xue Bao Yi Xue Ban ; 55(2): 357-361, 2023 Apr 18.
Artículo en Zh | MEDLINE | ID: mdl-37042150

RESUMEN

Placental transmogrification of the lung (PTL) is a very rare benign lung lesion. There are only about 40 cases reported in the literature. The imaging and histological features of PTL cases in the publication are various, most of which are cystic and a few of which are solid. Being extremely rare, the solid PTL is unknown to major pathologists and surgeons. We reported a case of solid PTL in the anterior mediastinum. The patient was a 52-year-old male with no history of smoking and without symptoms. During physical examination, chest CT revealed a circular low-density lesion with a maximum diameter of 2.9 cm beside the spine in the posterior basal segment of the left lower lobe of the lung. The wedge resection was performed by video-assisted thoracoscopy. Grossly, a round nodule was located underneath the visceral pleura. It was about 3.0 cm×3.0 cm×1.6 cm and the cut surface was grey-red, soft and spongy. Microscopically, the nodule was constituted of papillare, which resembled placental villi at low magnification. The axis of papillae was edema, in which some mild round cells with clear cytoplasm and CD10 positive staining aggregated and transitioned to immature adipocytes and amorphous pink materials deposited with a few of inflammatory cells infiltration. The surface of papillae was covered with disconti-nuous alveolar epithelium. Combined with the typical morphology and immunohistochemical characteristics of CD10 positive, the diagnosis was PTL. The patient was followed up for 1 year without recurrence and discomfort. So far, the pathogenesis of PTL is unclear. The major hypotheses include hamartoma, variant of emphysema and clonal hyperplasia of stromal cells. Based on the study of our case and publication, we speculate that the hyperplasia of stromal cells located in the alveolar septa might be the first step to form the solid PTL. With the progression of the disease, a typical unilateral cystic nodule develops as a result of secondary cystic degeneration due to the occlusive valve effect. Surgery is the only option for diagnosis and treatment of PTL. The clinician should make an individualized operation plan according to the clinical manifestations, location and scope of the lesion, and preserve the surrounding normal lung tissue as much as possible while completely removing the lesion. There is a favorable prognosis.


Asunto(s)
Placenta , Enfisema Pulmonar , Masculino , Humanos , Femenino , Embarazo , Persona de Mediana Edad , Hiperplasia/patología , Placenta/patología , Pulmón/patología , Enfisema Pulmonar/patología , Enfisema Pulmonar/cirugía , Tomografía Computarizada por Rayos X/métodos
3.
Zhonghua Yan Ke Za Zhi ; 59(9): 702-708, 2023 Sep 11.
Artículo en Zh | MEDLINE | ID: mdl-36822593

RESUMEN

Objective: To compare the efficacy and safety of trabeculotome tunnelling trabeculoplasty and gonioscopy-assisted transluminal trabeculotomy (GATT) in the treatment of open-angle glaucoma. Methods: A prospective randomized controlled study. The patients with open-angle glaucoma diagnosed in the ophthalmology center of Beijing Tongren Hospital affiliated to Capital Medical University from January to July 2022 were collected and divided into GATT group (undergoing GATT) and 3T group (undergoing 3T operation) using a random number table. Intraocular pressure (IOP) was recorded for both groups at 1 day, 1 week, 1 month, and 3 months after the operation, and the types and quantities of anti-glaucoma drugs used, postoperative complications, and surgical success rate were compared. Normal distribution measurement data were analyzed using independent sample t-tests, non-normal distribution measurement data were analyzed using non-parametric tests, and counting data were analyzed using chi-square tests. Results: This study included 35 patients (43 eyes), consisting of 27 males and 8 females, with an average age of (43.0±14.3) years. There were 21 patients (23 eyes) in the GATT group and 19 patients (20 eyes) in the 3T group. The maximum IOP without anti-glaucoma drugs before surgery, the highest IOP with the maximum number of anti-glaucoma drugs, and the IOP at 3 months after surgery in the GATT group were (33.5±9.1), (22.2±6.1), and (16.0±3.1) mmHg (1 mmHg=0.133 kPa), respectively. The corresponding values for the 3T group were (35.2±7.8), (21.5±6.8), and (16.1±2.0) mmHg. After surgery, the IOP in both groups was lower than before surgery, with a statistically significant difference (P<0.05) and no significant difference between the two groups (P>0.05). In the 3 months following surgery, 13 eyes in the GATT group and 11 eyes in the 3T group received more than two types of anti-glaucoma drugs, with no significant difference between the two groups (P>0.05). Three months after surgery, the complete and conditional success rates of the GATT group were 14/18 and 16/18, respectively, and those of the 3T group were 12/15 and 13/15, respectively, with no significant difference between the two groups (P>0.05). The incidence of hyphema, ciliary detachment, and shallow anterior chamber 1 day after surgery was 91%(21/23), 35%(8/23), and 30%(7/23), respectively, in the GATT group and 55%(11/20), 5%(1/20), and 0 in the 3T group, with a statistically significant difference between the two groups (P<0.05). Conclusion: 3T and GATT have similar success rates in the treatment of open-angle glaucoma. However, compared with GATT, 3T has fewer complications and is considered to be safer. (This article was published ahead of print on the Online-First Publishing Platform for Excellent Scientific Researches of Chinese Medical Association Publishing House on February 28, 2023).


Asunto(s)
Glaucoma de Ángulo Abierto , Trabeculectomía , Masculino , Femenino , Humanos , Adulto , Persona de Mediana Edad , Glaucoma de Ángulo Abierto/diagnóstico , Estudios Prospectivos , Agentes Antiglaucoma , Estudios de Seguimiento , Estudios Retrospectivos , Presión Intraocular , Gonioscopía , Resultado del Tratamiento
4.
Opt Lett ; 47(11): 2830-2833, 2022 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-35648941

RESUMEN

Existing nonlinear-optic implementations of pure, unfiltered heralded single-photon sources do not offer the scalability required for densely integrated quantum networks. Additionally, lithium niobate has hitherto been unsuitable for such use due to its material dispersion. We engineer the dispersion and the quasi-phasematching conditions of a waveguide in the rapidly emerging thin-film lithium niobate platform to generate spectrally separable photon pairs in the telecommunications band. Such photon pairs can be used as spectrally pure heralded single-photon sources in quantum networks. We estimate a heralded-state spectral purity of >94% based on joint spectral intensity measurements. Further, a joint spectral phase-sensitive measurement of the unheralded time-integrated second-order correlation function yields a heralded-state purity of (86±5)%.

5.
Genes Dev ; 28(6): 594-607, 2014 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-24589552

RESUMEN

During meiosis, homologous chromosome (homolog) pairing is promoted by several layers of regulation that include dynamic chromosome movement and meiotic recombination. However, the way in which homologs recognize each other remains a fundamental issue in chromosome biology. Here, we show that homolog recognition or association initiates upon entry into meiotic prophase before axis assembly and double-strand break (DSB) formation. This homolog association develops into tight pairing only during or after axis formation. Intriguingly, the ability to recognize homologs is retained in Sun1 knockout spermatocytes, in which telomere-directed chromosome movement is abolished, and this is the case even in Spo11 knockout spermatocytes, in which DSB-dependent DNA homology search is absent. Disruption of meiosis-specific cohesin RAD21L precludes the initial association of homologs as well as the subsequent pairing in spermatocytes. These findings suggest the intriguing possibility that homolog recognition is achieved primarily by searching for homology in the chromosome architecture as defined by meiosis-specific cohesin rather than in the DNA sequence itself.


Asunto(s)
Proteínas de Ciclo Celular/metabolismo , Proteínas Cromosómicas no Histona/metabolismo , Emparejamiento Cromosómico/fisiología , Meiosis/fisiología , Espermatocitos/fisiología , Animales , Proteínas de Ciclo Celular/genética , Proteínas Cromosómicas no Histona/genética , Emparejamiento Cromosómico/genética , Cromosomas/metabolismo , Endodesoxirribonucleasas/genética , Endodesoxirribonucleasas/metabolismo , Femenino , Técnicas de Inactivación de Genes , Hibridación Fluorescente in Situ , Masculino , Meiosis/genética , Ratones , Ratones Endogámicos C57BL , Proteínas Asociadas a Microtúbulos/genética , Proteínas Asociadas a Microtúbulos/metabolismo , Espermatocitos/metabolismo , Cohesinas
6.
Bull Exp Biol Med ; 174(1): 13-17, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36449110

RESUMEN

Behavioral changes in newborn 3-day-old rats (n=44) with modeled hypoxic-ischemic brain injury (HIBI) were observed, and the expression of CDK8 in brain tissues was detected to clarify the significance of CDK8. In 30 min, 3 h, and 3 days after HIBI, the left (ischemic) hemisphere was taken for examination. In 3 days after HIBI, the rat pups were examined in the behavioral tests. In rat pups with HIBI, changes of CDK8 expression were detected by Western blotting and real-time PCR and changes in the righting reflex and forelimb grip strength test (p<0.05) were revealed in comparison with sham-operated animals. The expression of CDK8 increased 30 min after HIBI and decreased in 3 h and 3 days. Hypoxia and ischemia of the left brain may affect locomotion, but not sensation. Since CDK8 is involved in the immune response after cerebral hypoxia and ischemia, this kinase can be used as an early diagnostic index.


Asunto(s)
Lesiones Encefálicas , Encéfalo , Animales , Ratas , Animales Recién Nacidos , Isquemia
7.
PLoS Biol ; 15(3): e2001192, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-28267757

RESUMEN

Student creation of educational materials has the capacity both to enhance learning and to decrease costs. Three successive honors-style classes of undergraduate students in a cancer genetics class worked with a new software system, CuboCube, to create an e-textbook. CuboCube is an open-source learning materials creation system designed to facilitate e-textbook development, with an ultimate goal of improving the social learning experience for students. Equipped with crowdsourcing capabilities, CuboCube provides intuitive tools for nontechnical and technical authors alike to create content together in a structured manner. The process of e-textbook development revealed both strengths and challenges of the approach, which can inform future efforts. Both the CuboCube platform and the Cancer Genetics E-textbook are freely available to the community.


Asunto(s)
Acceso a la Información , Neoplasias/genética , Aprendizaje Social , Programas Informáticos , Estudiantes , Libros de Texto como Asunto
8.
N Engl J Med ; 374(23): 2246-55, 2016 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-27276562

RESUMEN

BACKGROUND: Whole-exome sequencing has transformed gene discovery and diagnosis in rare diseases. Translation into disease-modifying treatments is challenging, particularly for intellectual developmental disorder. However, the exception is inborn errors of metabolism, since many of these disorders are responsive to therapy that targets pathophysiological features at the molecular or cellular level. METHODS: To uncover the genetic basis of potentially treatable inborn errors of metabolism, we combined deep clinical phenotyping (the comprehensive characterization of the discrete components of a patient's clinical and biochemical phenotype) with whole-exome sequencing analysis through a semiautomated bioinformatics pipeline in consecutively enrolled patients with intellectual developmental disorder and unexplained metabolic phenotypes. RESULTS: We performed whole-exome sequencing on samples obtained from 47 probands. Of these patients, 6 were excluded, including 1 who withdrew from the study. The remaining 41 probands had been born to predominantly nonconsanguineous parents of European descent. In 37 probands, we identified variants in 2 genes newly implicated in disease, 9 candidate genes, 22 known genes with newly identified phenotypes, and 9 genes with expected phenotypes; in most of the genes, the variants were classified as either pathogenic or probably pathogenic. Complex phenotypes of patients in five families were explained by coexisting monogenic conditions. We obtained a diagnosis in 28 of 41 probands (68%) who were evaluated. A test of a targeted intervention was performed in 18 patients (44%). CONCLUSIONS: Deep phenotyping and whole-exome sequencing in 41 probands with intellectual developmental disorder and unexplained metabolic abnormalities led to a diagnosis in 68%, the identification of 11 candidate genes newly implicated in neurometabolic disease, and a change in treatment beyond genetic counseling in 44%. (Funded by BC Children's Hospital Foundation and others.).


Asunto(s)
Exoma , Pruebas Genéticas/métodos , Errores Innatos del Metabolismo/genética , Análisis de Secuencia de ADN/métodos , Adolescente , Adulto , Niño , Preescolar , Femenino , Genotipo , Humanos , Lactante , Discapacidad Intelectual/genética , Masculino , Errores Innatos del Metabolismo/diagnóstico , Fenotipo , Adulto Joven
9.
Ann Oncol ; 30(7): 1104-1113, 2019 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-30977778

RESUMEN

BACKGROUND: Immune checkpoint blockade with Programmed cell death 1 (PD-1)/PD-L1 inhibitors has been effective in various malignancies and is considered as a standard treatment modality for patients with non-small-cell lung cancer (NSCLC). However, emerging evidence show that PD-1/PD-L1 blockade can lead to hyperprogressive disease (HPD), a flair-up of tumor growth linked to dismal prognosis. This study aimed to evaluate the incidence of HPD and identify the determinants associated with HPD in patients with NSCLC treated with PD-1/PD-L1 blockade. PATIENTS AND METHODS: We enrolled patients with recurrent and/or metastatic NSCLC treated with PD-1/PD-L1 inhibitors between April 2014 and November 2018. Clinicopathologic variables, dynamics of tumor growth, and treatment outcomes were analyzed in patients with NSCLC who received PD-1/PD-L1 blockade. HPD was defined according to tumor growth kinetics (TGK), tumor growth rate (TGR), and time to treatment failure (TTF). Immunophenotyping of peripheral blood CD8+ T lymphocytes was conducted to explore the potential predictive biomarkers of HPD. RESULTS: A total of 263 patients were analyzed. HPD was observed in 55 (20.9%), 54 (20.5%), and 98 (37.3%) patients according to the TGK, TGR, and TTF. HPD meeting both TGK and TGR criteria was associated with worse progression-free survival [hazard ratio (HR) 4.619; 95% confidence interval (CI) 2.868-7.440] and overall survival (HR, 5.079; 95% CI, 3.136-8.226) than progressive disease without HPD. There were no clinicopathologic variables specific for HPD. In the exploratory biomarker analysis with peripheral blood CD8+ T lymphocytes, a lower frequency of effector/memory subsets (CCR7-CD45RA- T cells among the total CD8+ T cells) and a higher frequency of severely exhausted populations (TIGIT+ T cells among PD-1+CD8+ T cells) were associated with HPD and inferior survival rate. CONCLUSION: HPD is common in NSCLC patients treated with PD-1/PD-L1 inhibitors. Biomarkers derived from rationally designed analysis may successfully predict HPD and worse outcomes, meriting further investigation of HPD.


Asunto(s)
Antineoplásicos Inmunológicos/uso terapéutico , Antígeno B7-H1/antagonistas & inhibidores , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/patología , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/patología , Receptor de Muerte Celular Programada 1/antagonistas & inhibidores , Adulto , Anciano , Anciano de 80 o más Años , Linfocitos T CD8-positivos/inmunología , Carcinoma de Pulmón de Células no Pequeñas/inmunología , Progresión de la Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Neoplasias Pulmonares/inmunología , Metástasis Linfática , Linfocitos Infiltrantes de Tumor/inmunología , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia , Recurrencia Local de Neoplasia/tratamiento farmacológico , Recurrencia Local de Neoplasia/inmunología , Recurrencia Local de Neoplasia/patología , Pronóstico , Tasa de Supervivencia , Carga Tumoral
10.
Proc Natl Acad Sci U S A ; 113(7): 1790-5, 2016 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-26839412

RESUMEN

Over 30 years ago, GGDEF domain-containing enzymes were shown to be diguanylate cyclases that produce cyclic di-GMP (cdiG), a second messenger that modulates the key bacterial lifestyle transition from a motile to sessile biofilm-forming state. Since then, the ubiquity of genes encoding GGDEF proteins in bacterial genomes has established the dominance of cdiG signaling in bacteria. However, the observation that proteobacteria encode a large number of GGDEF proteins, nearing 1% of coding sequences in some cases, raises the question of why bacteria need so many GGDEF enzymes. In this study, we reveal that a subfamily of GGDEF enzymes synthesizes the asymmetric signaling molecule cyclic AMP-GMP (cAG or 3', 3'-cGAMP). This discovery is unexpected because GGDEF enzymes function as symmetric homodimers, with each monomer binding to one substrate NTP. Detailed analysis of the enzyme from Geobacter sulfurreducens showed it is a dinucleotide cyclase capable of switching the major cyclic dinucleotide (CDN) produced based on ATP-to-GTP ratios. We then establish through bioinformatics and activity assays that hybrid CDN-producing and promiscuous substrate-binding (Hypr) GGDEF enzymes are found in other deltaproteobacteria. Finally, we validated the predictive power of our analysis by showing that cAG is present in surface-grown Myxococcus xanthus. This study reveals that GGDEF enzymes make alternative cyclic dinucleotides to cdiG and expands the role of this widely distributed enzyme family to include regulation of cAG signaling.


Asunto(s)
Proteínas de Escherichia coli/metabolismo , Nucleótidos Cíclicos/biosíntesis , Liasas de Fósforo-Oxígeno/metabolismo , Deltaproteobacteria/enzimología , Proteínas de Escherichia coli/química , Liasas de Fósforo-Oxígeno/química , Conformación Proteica
11.
Biochemistry ; 57(1): 108-116, 2018 01 09.
Artículo en Inglés | MEDLINE | ID: mdl-29052983

RESUMEN

Intracellular signaling enzymes drive critical changes in cellular physiology and gene expression, but their endogenous activities in vivo remain highly challenging to study in real time and for individual cells. Here we show that flow cytometry can be performed in complex media to monitor single-cell population distributions and dynamics of cyclic di-GMP signaling, which controls the bacterial colonization program. These in vivo biochemistry experiments are enabled by our second-generation RNA-based fluorescent (RBF) biosensors, which exhibit high fluorescence turn-on in response to cyclic di-GMP. Specifically, we demonstrate that intracellular levels of cyclic di-GMP in Escherichia coli are repressed with excess zinc, but not with other divalent metals. Furthermore, in both flow cytometry and fluorescence microscopy setups, we monitor the dynamic increase in cellular cyclic di-GMP levels upon zinc depletion and show that this response is due to de-repression of the endogenous diguanylate cyclase DgcZ. In the presence of zinc, cells exhibit enhanced cell motility and increased sensitivity to antibiotics due to inhibited biofilm formation. Taken together, these results showcase the application of RBF biosensors in visualizing single-cell dynamic changes in cyclic di-GMP signaling in direct response to environmental cues such as zinc and highlight our ability to assess whether observed phenotypes are related to specific signaling enzymes and pathways.


Asunto(s)
Técnicas Biosensibles , GMP Cíclico/análogos & derivados , Escherichia coli/metabolismo , ARN/química , Análisis de la Célula Individual , Zinc/metabolismo , GMP Cíclico/metabolismo , Citometría de Flujo , Microscopía Fluorescente , Transducción de Señal
12.
Nucleic Acids Res ; 44(17): e139, 2016 09 30.
Artículo en Inglés | MEDLINE | ID: mdl-27382070

RESUMEN

Bacteria occupy a diverse set of environmental niches with differing oxygen availability. Anaerobic environments such as mammalian digestive tracts and industrial reactors harbor an abundance of both obligate and facultative anaerobes, many of which play significant roles in human health and biomanufacturing. Studying bacterial function under partial or fully anaerobic conditions, however, is challenging given the paucity of suitable live-cell imaging tools. Here, we introduce a series of RNA-based fluorescent biosensors that respond selectively to cyclic di-GMP, an intracellular bacterial second messenger that controls cellular motility and biofilm formation. We demonstrate the utility of these biosensors in vivo under both aerobic and anaerobic conditions, and we show that biosensor expression does not interfere with the native motility phenotype. Together, our results attest to the effectiveness and versatility of RNA-based fluorescent biosensors, priming further development and application of these and other analogous sensors to study host-microbial and microbial-microbial interactions through small molecule signals.


Asunto(s)
Técnicas Biosensibles/métodos , GMP Cíclico/análogos & derivados , ARN/metabolismo , Anaerobiosis , Aptámeros de Nucleótidos/metabolismo , GMP Cíclico/análisis , Escherichia coli/crecimiento & desarrollo , Escherichia coli/metabolismo , Citometría de Flujo , Proteínas Fluorescentes Verdes/metabolismo , Movimiento , Fenotipo , Filogenia , Espectrometría de Fluorescencia
13.
RNA ; 20(7): 1153-60, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24860014

RESUMEN

Riboswitch aptamers adopt diverse and complex tertiary structural folds that contain both single-stranded and double-stranded regions. We observe that this high degree of secondary structure leads to an appreciable hypochromicity that is not accounted for in the standard method to calculate extinction coefficients using nearest-neighbor effects, which results in a systematic underestimation of RNA concentrations. Here we present a practical method for quantifying riboswitch RNAs using thermal hydrolysis to generate the corresponding pool of mononucleotides, for which precise extinction coefficients have been measured. Thermal hydrolysis can be performed at neutral pH without reaction quenching, avoids the use of nucleases or expensive fluorescent dyes, and does not require generation of calibration curves. The accuracy of this method for determining RNA concentrations has been validated using quantitative (31)P-NMR calibrated to an external standard. We expect that this simple procedure will be generally useful for the accurate quantification of any sequence-defined RNA sample, which is often a critical parameter for in vitro binding and kinetic assays.


Asunto(s)
Conformación de Ácido Nucleico , ARN/análisis , Riboswitch , Aptámeros de Nucleótidos/análisis , Aptámeros de Nucleótidos/química , Aptámeros de Nucleótidos/metabolismo , Secuencia de Bases , Concentración de Iones de Hidrógeno , Hidrólisis , Datos de Secuencia Molecular , Desnaturalización de Ácido Nucleico , ARN/química , ARN/metabolismo , Espectrofotometría Ultravioleta , Temperatura
14.
Int J Obes (Lond) ; 40(3): 443-51, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26403433

RESUMEN

BACKGROUND/OBJECTIVES: It has been reported that irisin regulated exercise-mediated adipocyte browning; however, the systematical effects of irisin on the metabolism of glucose and lipid in diabetes are largely unknown. In the present study, we investigated the role and underlying mechanism of irisin in glucose utilization and lipid metabolism in diabetic mice. METHODS: A mouse model of diabetes was established by feeding C57BL/6 mice with high-fat diet. The diabetic mice were then treated with irisin. To mimic type 2 diabetes in vitro, myocytes and hepatocytes were cultured in a medium of high glucose and high fat. Glucose uptake, fatty acid oxidation and the expression of related protein were evaluated. RESULTS: Irisin improved glucose tolerance and glucose uptake as evidenced by increased (18)F-FDG accumulation and GLUT4 translocation in diabetic skeletal muscle. Irisin also increased glucose uptake in myocytes cultured in high glucose/high fatty acid medium. In contrast, irisin reduced the expression of PEPCK and G6Pase, which are involved in gluconeogenesis, in diabetic liver. Consistently, irisin reduced fat weight and serum total cholesterol and triglyceride levels in diabetic mice, but increased acetyl coenzyme A carboxylase-ß phosphorylation in muscle tissue and uncoupling protein 1 expression in fat tissue. In addition, irisin increased the oxidation of fatty acid in myocytes. Knockdown of the adenosine monophosphate (AMP)-activated protein kinase (AMPK) attenuated the effects of irisin on glucose uptake and fatty acid ß-oxidation in myocytes. Similarly, inhibition of AMPK by a specific inhibitor reduced the effects of irisin on PEPCK and G6Pase expression in hepatocytes. CONCLUSIONS: Our results suggest that irisin has an essential role in glucose utilization and lipid metabolism, and irisin is a promising pharmacological target for the treatment of diabetes and its complications.


Asunto(s)
Proteínas Quinasas Activadas por AMP/metabolismo , Diabetes Mellitus Experimental/patología , Ácidos Grasos/metabolismo , Fibronectinas/farmacología , Glucosa/metabolismo , Músculo Esquelético/metabolismo , Animales , Glucemia/metabolismo , Modelos Animales de Enfermedad , Transportador de Glucosa de Tipo 4/metabolismo , Metabolismo de los Lípidos , Masculino , Ratones , Ratones Endogámicos C57BL , Oxidación-Reducción , Fosforilación , Transducción de Señal
15.
Andrologia ; 48(1): 116-20, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25737298

RESUMEN

Different outcomes after intracytoplasmic sperm injection (ICSI) without oocyte activation in two patients with different types of round-headed spermatozoa (globozoospermia) are reported. After controlled ovarian hyperstimulation and oocyte pick-up, retrieved oocytes were underwent ICSI without oocyte activation and a 33.33% (4/12) fertilisation rate was obtained in the first case, whereas an abnormal fertilisation was achieved in the second case. The transfer of two grade II embryos in the first couple resulted in clinical pregnancy with a healthy livebirth. It was concluded that the main problem of cases with globozoospermia was a low fertilisation rate or failure fertilisation, and even though ICSI and artificial oocyte activation have been employed to increase this rate, it is not necessarily needed to achieve a pregnancy.


Asunto(s)
Infertilidad Masculina/terapia , Oocitos , Resultado del Embarazo , Índice de Embarazo , Inyecciones de Esperma Intracitoplasmáticas/métodos , Espermatozoides/anomalías , Adulto , Femenino , Fertilización In Vitro , Humanos , Masculino , Embarazo
16.
BMC Med ; 13: 162, 2015 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-26162993

RESUMEN

BACKGROUND: The use of adult stem cells is limited by the quality and quantity of host stem cells. It has been demonstrated that Wharton's jelly-derived mesenchymal stem cells (WJMSCs), a primitive stromal population, could integrate into ischemic cardiac tissues and significantly improve heart function. In this randomized, controlled trial, our aim was to assess the safety and efficacy of intracoronary WJMSCs in patients with ST-elevation acute myocardial infarction (AMI). METHODS: In a multicenter trial, 116 patients with acute ST-elevation MI were randomly assigned to receive an intracoronary infusion of WJMSCs or placebo into the infarct artery at five to seven days after successful reperfusion therapy. The primary endpoint of safety: the incidence of adverse events (AEs) within 18 months, was monitored and quantified. The endpoint of efficacy: the absolute changes in myocardial viability and perfusion of the infarcted region from baseline to four months, global left ventricular ejection fraction (LVEF) from baseline to 18 months were measured using F-18-fluorodeoxyglucose positron emission computed tomography (F-18-FDG-PET) and 99mTc-sestamibi single-photon emission computed tomography (99mTc-SPECT), and two-dimensional echocardiography, respectively. RESULTS: During 18 months follow-up, AEs rates and laboratory tests including tumor, immune, and hematologic indexes were not different between the two groups. The absolute increase in the myocardial viability (PET) and perfusion within the infarcted territory (SPECT) was significantly greater in the WJMSC group [6.9 ± 0.6 % (95 %CI, 5.7 to 8.2)] and [7.1 ± 0.8 % (95 %CI, 5.4 to 8.8) than in the placebo group [3.3 ± 0.7 % (95 %CI, 1.8 to 4.7), P <0.0001] and 3.9 ± 0.6(95 %CI, 2.8 to 5.0), P = 0.002] at four months. The absolute increase in the LVEF at 18 months in the WJMSC group was significantly greater than that in the placebo group [7.8 ± 0.9 (6.0 to approximately 9.7) vs. 2.8 ± 1.2 (0.4 to approximately 5.1), P = 0.001]. Concomitantly, the absolute decreases in LV end-systolic volumes and end-diastolic volumes at 18 months in the WJMSC group were significantly greater than those in the placebo group (P = 0.0004, P = 0.004, respectively). CONCLUSIONS: Intracoronary infusion of WJMSCs is safe and effective in patients with AMI, providing clinically relevant therapy within a favorable time window. This study encourages additional clinical trials to determine whether WJMSCs may serve as a novel alternative to BMSCs for cardiac stem cell-based therapy. TRIAL REGISTRATION: Clinical Trials NCT01291329 (02/05/2011).


Asunto(s)
Trasplante de Células Madre Mesenquimatosas/métodos , Infarto del Miocardio/terapia , Adulto , Anciano , Método Doble Ciego , Ecocardiografía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Tomografía Computarizada de Emisión de Fotón Único , Resultado del Tratamiento , Función Ventricular Izquierda , Gelatina de Wharton
17.
Cell Mol Biol (Noisy-le-grand) ; 61(3): 102-6, 2015 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-26255139

RESUMEN

Withaferin A (WFA) is an active compound from Withania somnifera and has been reported to exhibit a variety of pharmacological activities such as anti—inflammatory, immunomodulatory and anti—tumor properties. In the present study, we investigated the potential protective role of WFA on acute lung injury in neonatal rats induced by lipopolysaccharide (LPS). We found that WFA significantly attenuated the pathological changes of lungs induced by LPS injection. Administration with WFA obviously decreased pulmonary neutrophil infiltration accompanied with decreased MPO concentrations. WFA also reduced the expression of pro—inflammatory cytokines including MIP—2, TNF—α, IL—1β and IL—6. Meanwhile, the expression levels of anti—inflammatory mediators such as TGF—β1 and IL—10 were significantly increased following WFA administration. Moreover, WFA protected LPS—treated rats from oxidative damage via up—regulation of TBARS and H2O2 concentrations and down—regulation of ROS contents. Taken together, the present study demonstrated that WFA administration attenuated LPS—induced lung injury through inhibition of inflammatory responses and oxidative stress.


Asunto(s)
Lesión Pulmonar Aguda/prevención & control , Witanólidos/administración & dosificación , Lesión Pulmonar Aguda/etiología , Animales , Animales Recién Nacidos , Citocinas/análisis , Citocinas/metabolismo , Modelos Animales de Enfermedad , Regulación hacia Abajo/efectos de los fármacos , Ensayo de Inmunoadsorción Enzimática , Peróxido de Hidrógeno/metabolismo , Lipopolisacáridos/toxicidad , Pulmón/efectos de los fármacos , Pulmón/metabolismo , Pulmón/patología , Masculino , Estrés Oxidativo/efectos de los fármacos , Ratas , Ratas Wistar , Especies Reactivas de Oxígeno/metabolismo , Regulación hacia Arriba/efectos de los fármacos , Withania/química , Withania/metabolismo , Witanólidos/química , Witanólidos/farmacología
18.
Nan Fang Yi Ke Da Xue Xue Bao ; 44(1): 187-193, 2024 Jan 20.
Artículo en Zh | MEDLINE | ID: mdl-38293991

RESUMEN

OBJECTIVE: To investigate the role of SIRT1/autophagy pathway in mediating the regulatory effect of lncRNA SOX2OT on 5-fluorouracil (5-FU) resistance in cholangiocarcinoma cells. METHODS: HCCC-9810 cells were used to construct a 5-FU-resistant cell model (HCCC-9810/5-FU cells), and the expression levels of lncRNA SOX2OT and SIRT1 mRNA and the protein expressions of SIRT1, Beclin1, LC3 and P62 were detected with qRT-PCR and Western blotting. The effects of transfection with a SOX2OT mimic on drug resistance and cell migration of HCCC-9810/5-FU cells were detected using CCK-8 assay and wound healing assay, and the changes in expressions of SOX2OT, SIRT1, Beclin1, LC3 and P62 were detected. Rescue experiment was performed by co-transfection of HCCC-9810/5-FU cells with both a SOX2OT-overexpressing plasmid and si-SIRT1 to confirm the role of SIRT1 in SOX2OT-mediated regulation of 5-FU resistance. A RNA pulldown assay was used to verify the targeted binding between SOX2OT and SIRT1. RESULTS: The proliferation of HCCC-9810 cells was significantly inhibited after treatment with different concentrations of 5-FU (P < 0.05). The 5-FU-resistant cells showed significantly increased protein expressions of SIRT1, Beclin1 and p62, an increased LC3 Ⅱ/LC3 Ⅰ ratio, and enhanced expressions of SIRT1 mRNA and SOX2OT (P < 0.05). Transfection of the resistant cells with SOX2OT mimic significantly enhanced cell migration and increased the protein expressions of SIRT1, Beclin1 and p62, the LC3Ⅱ/LC3Ⅰ ratio, and expression levels of SIRT1 mRNA and SOX2OT (P < 0.05), and these changes were obviously attenuated by SIRT1 knockdown, which also resulted in lowered 5-FU resistance of the cells without significantly affecting the expression level of SOX2OT (P > 0.05). RNA pulldown assay suggested that SOX2OT could directly bind to SIRT1. CONCLUSION: LncRNA SOX2OT enhances 5-FU resistance in HCCC-9810 cells by promoting autophagy through up-regulating SIRT1 expression.


Asunto(s)
Colangiocarcinoma , ARN Largo no Codificante , Humanos , Autofagia , Beclina-1 , Línea Celular Tumoral , Colangiocarcinoma/genética , Colangiocarcinoma/tratamiento farmacológico , Fluorouracilo/farmacología , ARN Largo no Codificante/genética , ARN Mensajero , Sirtuina 1/genética
19.
Int J Audiol ; 52(12): 801-7, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24175619

RESUMEN

OBJECTIVE: This study tested multiple dosing epochs of pre-loaded D-methionine (D-met) for otoprotection from noise-induced hearing loss (NIHL). DESIGN: Auditory brainstem response (ABR) thresholds were measured at baseline, 1 day, and 21 days following a 6-hour 105 dB sound pressure level (SPL) octave band noise (OBN) exposure. Outer hair cell (OHC) counts were measured after day 21 sacrifice. STUDY SAMPLE: Three groups of five Chinchillas laniger each were given a 2-day regimen comprising five doses of D-met (200 mg/kg/dose) intraperitoneally (IP) starting 2, 2.5, or 3 days prior to noise exposure. A control group (n = 5) received five doses of equivalent volume saline IP starting 2.5 days prior to noise exposure. RESULTS: ABR threshold shifts from baseline to day-21 post-noise exposure were reduced in all D-met groups versus controls, reaching significance (p < 0.05) in the 3-day group. D-met groups showed reduced OHC loss relative to controls at day-21 post-noise exposure, reaching significance (p < 0.05) at all frequency regions in the 3-day group and at the 2, 4, and 8 kHz frequency regions in the 2.5-day group. CONCLUSIONS: D-met administration in advance of noise-exposure, without further administration, significantly protects from noise-induced ABR threshold shift and OHC loss.


Asunto(s)
Umbral Auditivo/efectos de los fármacos , Células Ciliadas Auditivas Externas/efectos de los fármacos , Pérdida Auditiva Provocada por Ruido/prevención & control , Metionina/administración & dosificación , Animales , Chinchilla , Citoprotección , Modelos Animales de Enfermedad , Potenciales Evocados Auditivos del Tronco Encefálico/efectos de los fármacos , Células Ciliadas Auditivas Externas/patología , Pérdida Auditiva Provocada por Ruido/patología , Pérdida Auditiva Provocada por Ruido/fisiopatología , Pérdida Auditiva Provocada por Ruido/psicología , Masculino , Factores de Tiempo
20.
Nan Fang Yi Ke Da Xue Xue Bao ; 43(3): 454-459, 2023 Mar 20.
Artículo en Zh | MEDLINE | ID: mdl-37087591

RESUMEN

OBJECTIVE: To investigate the mechanism by which SIRT1 silencing reduces 5-fluorouracil (5-FU) resistance of cholangiocarcinoma cells and the role of FOXO1/Rab7 autophagy pathway in mediating this effect. METHODS: Human cholangiocarcinoma HCCC-9810 cells were treated with 50, 100, 150, and 200 µg/mL 5-FU to construct a 5-FU-resistant cell model, whose expressions of SIRT1, FOXO1 and Rab7 were detected with immunofluorescence assay, Western blotting and RTqPCR, and the expression levels of autophagy related proteins (Beclin1, LC3, and p62) were detected with Western blotting. The 5-FU resistant cells were transfected with a SIRT1 siRNA, and the changes in 5-Fu resistance and migration ability of the cells were evaluated using CCK-8 assay and wound healing assay; The changes in FOXO1 and Rab7 mRNA levels and protein expressions of SIRT1, FOXO1, Rab7, Beclin1, LC3 and P62 were detected with RT-qPCR and Western blotting. RESULTS: Treatments with 5-FU at 50, 100, 150, and 200 µg/mL all inhibited the proliferation of HCCC-9810 cells. Immunofluorescence assay revealed significantly enhanced SIRT1 expression in 5-FU-resistant HCC-9810 cells, and Western blotting also showed significantly up-regulated protein expressions of SIRT1, Rab7, P62, FOXO1 and Beclin 1 (P < 0.001) and an increased LC3II/LC3I ratio in the cells (P < 0.001). The mRNA levels of SIRT1, Rab7 and FOXO1 were also up-regulated in 5-Fu-resistant cells (P < 0.05). SIRT1 silencing significantly attenuated 5-FU resistance and migration ability of HCCC-9810 cells, and obviously decreased the protein expressions of SIRT1, Rab7, P62, FOXO1 and Beclin1 and the LC3II/LC3I ratio as well (P < 0.001). FOXO1 and Rab7 mRNA levels were significantly decreased in 5-FU-resistant HCC-9810 cells after SIRT1 silencing (P < 0.05). CONCLUSION: Silencing SIRT1 attenuates 5-FU resistance in HCC-9810 cells by inhibiting the activation of the FOXO1/Rab7 autophagy pathway.


Asunto(s)
Autofagia , Colangiocarcinoma , Resistencia a Antineoplásicos , Fluorouracilo , Sirtuina 1 , Humanos , Autofagia/genética , Beclina-1 , Neoplasias de los Conductos Biliares/tratamiento farmacológico , Neoplasias de los Conductos Biliares/patología , Conductos Biliares Intrahepáticos/metabolismo , Conductos Biliares Intrahepáticos/patología , Carcinoma Hepatocelular , Colangiocarcinoma/tratamiento farmacológico , Colangiocarcinoma/patología , Resistencia a Antineoplásicos/genética , Fluorouracilo/farmacología , Proteína Forkhead Box O1/genética , Proteína Forkhead Box O1/metabolismo , Proteína Forkhead Box O1/farmacología , Neoplasias Hepáticas , Proteínas de Unión a GTP rab7/metabolismo , ARN Mensajero , Sirtuina 1/genética , Sirtuina 1/metabolismo
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