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1.
Proc Natl Acad Sci U S A ; 119(49): e2215966119, 2022 12 06.
Artículo en Inglés | MEDLINE | ID: mdl-36445965

RESUMEN

Surveillance of Caenorhabditis elegans mitochondrial status is coupled to defense responses such as drug detoxification, immunity, antiviral RNA interference (RNAi), and regulation of life span. A cytochrome p540 detoxification gene, cyp-14A4, is specifically activated by mitochondrial dysfunction. The nuclear hormone receptor NHR-45 and the transcriptional Mediator component MDT-15/MED15 are required for the transcriptional activation of cyp-14A4 by mitochondrial mutations, gene inactivations, or toxins. A genetic screen for mutations that fail to activate this cytochrome p450 gene upon drug or mutation-induced mitochondrial dysfunction identified a DNA helicase ARIP-4 that functions in concert with the NHR-45 transcriptional regulatory cascade. In response to mitochondrial dysfunction, ARIP-4 and NHR-45 protein interaction is enhanced, and they relocalize from the nuclear periphery to the interior of intestinal nuclei. NHR-45/ARIP-4 also regulates the transcriptional activation of the eol-1 gene that encodes a decapping enzyme required for enhanced RNAi and transgene silencing of mitochondrial mutants. In the absence of arip-4, animals were more susceptible to the mitochondrial inhibitor antimycin. Thus, ARIP-4 serves as a transcriptional coactivator of NHR-45 to promote this defense response. A null mutation in arip-4 extends the life span and health span of both wild type and a mitochondrial mutant, suggesting that the activation of detoxification pathways is deleterious to health when the mitochondrial dysfunction is caused by mutation that cannot be cytochrome p450-detoxified. Thus, arip-4 acts in a pathway that couples mitochondrial surveillance to the activation of downstream immunity, detoxification, and RNAi responses.


Asunto(s)
Caenorhabditis , Animales , ADN Helicasas/genética , Caenorhabditis elegans/genética , Antivirales , Mitocondrias/genética
2.
BMC Pregnancy Childbirth ; 24(1): 514, 2024 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-39080617

RESUMEN

OBJECTIVE: Despite the World Health Organization's recommendation of exclusive breastfeeding for the initial 6 months, breastfeeding rates decline within the first 6 weeks after delivery. This study aimed to (1) investigate the breastfeeding rate at 6 weeks postpartum and (2) explore the influence of perinatal factors on feeding patterns at 6 weeks postpartum. METHOD: A total of 635 participants were enrolled from February to August 2023 at outpatient clinics in three tertiary hospitals in Nantong City. Variables were collected through questionnaires during the third trimester of pregnancy, including demographic information, pregnancy stress, anxiety, depression, sleep, and resilience. At 6 weeks postpartum, information regarding feeding patterns, delivery and postpartum situations, postpartum stress, anxiety, depression, sleep, and resilience was gathered. Initial single-factor analyses were conducted using feeding pattern as the dependent variable, and variables with significance were chosen as independent variables. The disordered multi-classification logistic regression model was then established using the stepwise forward method. RESULTS: Within the first 6 weeks, 35.28% (224/635) of postpartum women exclusively breastfed their infants. Factors influencing exclusive breastfeeding and formula feeding at 6 weeks postpartum included breast pain, sleep quality, mental resilience, difference between postpartum and late pregnancy anxiety, insufficient milk supply, and maternal herself caring for the infant (P < 0.05). Factors influencing the transition from exclusive to partial breastfeeding were insufficient milk supply and maternal herself caring for the infant (P < 0.05). CONCLUSION: The study reveals a relative low rate of exclusive breastfeeding in China's first 6 weeks postpartum, along with a comparison of perinatal factors affecting three different feeding patterns. Our findings may contribute additional evidence to the association between perinatal factors and feeding patterns. This study guides healthcare professionals in developing strategies to promote exclusive breastfeeding and improve personalized counseling for exclusive breastfeeding and mental health.


Asunto(s)
Lactancia Materna , Periodo Posparto , Humanos , Femenino , Lactancia Materna/psicología , Lactancia Materna/estadística & datos numéricos , Adulto , Embarazo , Periodo Posparto/psicología , China , Encuestas y Cuestionarios , Recién Nacido , Conducta Alimentaria/psicología , Madres/psicología , Tercer Trimestre del Embarazo , Factores de Tiempo
3.
Anal Chem ; 95(18): 7237-7243, 2023 05 09.
Artículo en Inglés | MEDLINE | ID: mdl-37120835

RESUMEN

DNA nanosheets (DNSs) have been utilized effectively as a fluorescence anisotropy (FA) amplifier for biosensing. But, their sensitivity needs to be further improved. Herein, CRISPR-Cas12a with strong trans-cleavage activity was utilized to enhance the FA amplification ability of DNSs for the sensitive detection of miRNA-155 (miR-155) as a proof-of-principle target. In this method, the hybrid of the recognition probe of miR-155 (T1) and a blocker sequence (T2) was immobilized on the surface of magnetic beads (MBs). In the presence of miR-155, T2 was released by a strand displacement reaction, which activated the trans-cleavage activity of CRISPR-Cas12a. The single-stranded DNA (ssDNA) probe modified with a carboxytetramethylrhodamine (TAMRA) fluorophore was cleaved in large quantities and could not bind to the handle chain on DNSs, inducing a low FA value. In contrast, in the absence of miR-155, T2 could not be released and the trans-cleavage activity of CRISPR-Cas12a could not be activated. The TAMRA-modified ssDNA probe remained intact and was complementary to the handle chain on the DNSs, and a high FA value was obtained. Thus, miR-155 was detected through the obviously decreased FA value with a low limit of detection (LOD) of 40 pM. Impressively, the sensitivity of this method was greatly improved about 322 times by CRISPR-Cas12a, confirming the amazing signal amplification ability of CRISPR-Cas12a. At the same time, the SARS-CoV-2 nucleocapsid protein was detected by the strategy successfully, indicating that this method was general. Moreover, this method has been applied in the analysis of miR-155 in human serum and the lysates of cells, which provides a new avenue for the sensitive determination of biomarkers in biochemical research and disease diagnosis.


Asunto(s)
Técnicas Biosensibles , COVID-19 , MicroARNs , Humanos , SARS-CoV-2 , ADN , ADN de Cadena Simple , Sistemas CRISPR-Cas/genética
4.
PLoS Biol ; 18(12): e3000996, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33264285

RESUMEN

RNA interference (RNAi) is an antiviral pathway common to many eukaryotes that detects and cleaves foreign nucleic acids. In mammals, mitochondrially localized proteins such as mitochondrial antiviral signaling (MAVS), retinoic acid-inducible gene I (RIG-I), and melanoma differentiation-associated protein 5 (MDA5) mediate antiviral responses. Here, we report that mitochondrial dysfunction in Caenorhabditis elegans activates RNAi-directed silencing via induction of a pathway homologous to the mammalian RIG-I helicase viral response pathway. The induction of RNAi also requires the conserved RNA decapping enzyme EOL-1/DXO. The transcriptional induction of eol-1 requires DRH-1 as well as the mitochondrial unfolded protein response (UPRmt). Upon mitochondrial dysfunction, EOL-1 is concentrated into foci that depend on the transcription of mitochondrial RNAs that may form double-stranded RNA (dsRNA), as has been observed in mammalian antiviral responses. Enhanced RNAi triggered by mitochondrial dysfunction is necessary for the increase in longevity that is induced by mitochondrial dysfunction.


Asunto(s)
Proteína 58 DEAD Box/metabolismo , Mitocondrias/metabolismo , Interferencia de ARN/fisiología , Proteínas Adaptadoras Transductoras de Señales , Animales , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Proteína 58 DEAD Box/fisiología , ARN Helicasas DEAD-box/metabolismo , Regulación de la Expresión Génica/genética , Helicasa Inducida por Interferón IFIH1/metabolismo , Mitocondrias/fisiología , ARN Bicatenario/genética , ARN Interferente Pequeño/genética , ARN Viral/genética , Transducción de Señal/genética
5.
Sensors (Basel) ; 23(5)2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36904913

RESUMEN

A wireless channel digital twin is a useful tool to evaluate the performance of a communication system at the physical or link level by generating the physical channel controllably. In this paper, a stochastic general fading channel model is proposed, which considered most of the channel fading types for various communication scenarios. By using the sum-of-frequency-modulation (SoFM) method, the phase discontinuity of the generated channel fading was well addressed. On this basis, a general and flexible generation architecture for channel fading was developed on a field programmable gate array (FPGA) platform. In this architecture, improved CORDIC-based hardware circuits for the trigonometric function, exponential function, and natural logarithm were designed and implemented, which improved the real-time performance of the system and the utilization rate of the hardware resources compared with the traditional LUT and CORDIC method. For a 16-bit fixed-point data bit width single-channel emulation, the hardware resource consumption was significantly reduced from 36.56% to 15.62% for the overall system by utilizing the compact time-division (TD) structure. Moreover, the classical CORDIC method brought an extra latency of 16 system clock cycles, while the latency caused by the improved CORDIC method was decreased by 62.5%. Finally, a generation scheme of a correlated Gaussian sequence was developed to introduce a controllable arbitrary space-time correlation for the channel generator with multiple channels. The output results of the developed generator were consistent with the theoretical results, which verified the correctness of both the generation method and hardware implementation. The proposed channel fading generator can be applied for the emulation of large-scale multiple-input, multiple-output (MIMO) channels under various dynamic communication scenarios.

6.
Int J Mol Sci ; 24(3)2023 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-36768636

RESUMEN

Evidence continues to accrue that aging and its diseases can be delayed by pharmacologic and dietary strategies that target the underlying hallmarks of the aging process. However, identifying simple, safe, and effective dietary strategies involving the incorporation of whole foods that may confer some protection against the aging process is also needed. Recent observational studies have suggested that nut consumption can reduce mortality risk in humans. Among these, walnuts are particularly intriguing, given their high content of n-3 fatty acids, fiber, and antioxidant and anti-inflammatory compounds. To this end, 12-month-old male CB6F1 mice were provided either a defined control low-fat diet (LFD), a control high-fat diet (HFD), or an isocaloric HFD containing 7.67% walnuts by weight (HFD + W), and measures of healthspan and related biochemical markers (n = 10-19 per group) as well as survival (n = 20 per group) were monitored. Mice provided the HFD or HFD + W demonstrated marked weight gain, but walnuts lowered baseline glucose (p < 0.05) and tended to temper the effects of HFD on liver weight gain (p < 0.05) and insulin tolerance (p = 0.1). Additional assays suggested a beneficial effect on some indicators of health with walnut supplementation, including preservation of exercise capacity and improved short-term working memory, as determined by Y maze (p = 0.02). However, no effect was observed via any diet on inflammatory markers, antioxidant capacity, or survival (p = 0.2). Ingenuity Pathway Analysis of the hippocampal transcriptome identified two processes predicted to be affected by walnuts and potentially linked to cognitive function, including estrogen signaling and lipid metabolism, with changes in the latter confirmed by lipidomic analysis. In summary, while walnuts did not significantly improve survival on a HFD, they tended to preserve features of healthspan in the context of a metabolic stressor with aging.


Asunto(s)
Juglans , Humanos , Masculino , Ratones , Animales , Anciano , Lactante , Juglans/química , Nueces/química , Dieta Alta en Grasa/efectos adversos , Lipidómica , Antioxidantes/análisis , Aumento de Peso , Ratones Endogámicos C57BL
7.
Sensors (Basel) ; 21(9)2021 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-34068456

RESUMEN

A new non-stationary (NS) geometry-based stochastic model (GBSM) is presented for developing and testing the communication systems of vehicle-to-vehicle (V2V) applications, which considers the three-dimensional (3D) scattering environments and allows 3D velocity as well. In this paper, the proposed GBSM for NS V2V channels allowed 3D velocity variations and was more suitable for actual V2V communications because it provided smoother transitions between the consecutive channel segments. The time-variant channel coefficient and the channel parameters, i.e., Doppler frequencies, path delay and power, angle of arrival (AoA), and angle of departure (AoD), were analyzed and derived. Likewise, the theoretical statistical properties as the probability density function (PDF), the auto-correlation function (ACF), and Doppler power spectral density (DPSD) were also analyzed and derived under the von Mises-Fisher (VMF) distribution. Finally, the theoretical and measured results were well coordinated alongside the implemented results, which confirmed the feasibility of the introduced model along with the theoretical expressions.

8.
Ann Surg Oncol ; 27(5): 1361-1371, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-31773517

RESUMEN

BACKGROUND: The aim of the present work is to develop and validate accurate preoperative nomograms to predict microvascular invasion (MVI) and lymph node metastasis (LNM) in hepatocellular carcinoma. PATIENTS AND METHODS: A total of 268 patients with resected hepatocellular carcinoma (HCC) were divided into a training set (n = 180), in an earlier period, and a validation set (n = 88), thereafter. Risk factors for MVI and LNM were assessed based on logistic regression. Blood signatures were established using the least absolute shrinkage and selection operator algorithm. Nomograms were constructed by combining risk factors and blood signatures. Performance was evaluated using the training set and validated using the validation set. The clinical values of the nomograms were measured by decision curve analysis. RESULTS: The risk factors for MVI were hepatitis B virus (HBV) DNA loading, portal hypertension, Barcelona liver clinic (BCLC) stage, and three computerized tomography (CT) imaging features, namely tumor number, size, and encapsulation, while only BCLC stage, Child-Pugh classification, and tumor encapsulation were associated with LNM. The nomogram incorporating both risk factors and blood signatures achieved better performance in predicting MVI in the training and validation sets (C-indexes of 0.828 and 0.804) than the LNM nomogram (C-indexes of 0.765 and 0.717). Calibration curves also demonstrated a good fit. The decision curves indicate significant clinical usefulness. CONCLUSIONS: The novel validated nomograms for HCC patients presented herein are noninvasive preoperative tools that can effectively predict the individualized risk of MVI and LNM, and this predictive power can aid doctors in explaining the illness for patient counseling.


Asunto(s)
Vasos Sanguíneos/patología , Carcinoma Hepatocelular/patología , Neoplasias Hepáticas/patología , Ganglios Linfáticos/patología , Nomogramas , Adulto , Fosfatasa Alcalina/sangre , Aspartato Aminotransferasas/sangre , Carcinoma Hepatocelular/sangre , Carcinoma Hepatocelular/complicaciones , Carcinoma Hepatocelular/diagnóstico por imagen , ADN Viral/sangre , Técnicas de Apoyo para la Decisión , Femenino , Venas Hepáticas/patología , Virus de la Hepatitis B , Hepatitis B Crónica/complicaciones , Humanos , Hipertensión Portal/complicaciones , Imagenología Tridimensional , Cirrosis Hepática/complicaciones , Cirrosis Hepática/diagnóstico por imagen , Neoplasias Hepáticas/sangre , Neoplasias Hepáticas/complicaciones , Neoplasias Hepáticas/diagnóstico por imagen , Modelos Logísticos , Metástasis Linfática , Masculino , Persona de Mediana Edad , Invasividad Neoplásica , Vena Porta/patología , Reproducibilidad de los Resultados , Estudios Retrospectivos , Factores de Riesgo , Tomografía Computarizada por Rayos X , Carga Tumoral , Carga Viral , alfa-Fetoproteínas/metabolismo
9.
Cancer Cell Int ; 20: 140, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32368186

RESUMEN

BACKGROUND: The primary tumor, regional lymph nodes and distant metastasis (TNM) stage is an independent risk factor for 1-year hepatocellular carcinoma (HCC) recurrence but has insufficient predictive efficiency. We attempt to develop and validate a nomogram to predict 1-year recurrence in HCC and improve the predictive efficiency of the TNM stage. METHODS: A total of 541 HCC patients were enrolled in the study. The risk score (RS) model was established with the logistic least absolute shrinkage and selector operation algorithm. The predictive nomogram was further validated in the internal testing cohort and external validation cohort. The area under the receiver operating characteristic curves (AUCs), decision curves and clinical impact curves were used to evaluate the predictive accuracy and clinical value of the nomogram. RESULTS: In the training cohort, we identified a RS model consisting of five stage-related genes (NUP62, EHMT2, RANBP1, MSH6 and FHL2) for recurrence at 1 year. The 1-year disease-free survival of patients was worse in the high-risk group than in the low-risk group (P < 0.0001), and 1-year recurrence was more likely in the high-risk group (Hazard ratio: 3.199, P < 0.001). The AUC of the nomogram was 0.739, 0.718 and 0.693 in the training, testing and external validation cohort, respectively, and these values were larger than the corresponding AUC of the TNM stage (0.681, 0.688 and 0.616, respectively). CONCLUSIONS: A RS model consisting of five stage-related genes was successfully identified for predicting 1-year HCC recurrence. Then, a novel nomogram based on the RS model and TNM stage to predict 1-year HCC recurrence was also developed and validated.

10.
Sensors (Basel) ; 20(23)2020 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-33291413

RESUMEN

Considering the three-dimensional (3D) trajectory, 3D antenna array, and 3D beamforming of unmanned aerial vehicle (UAV), a novel non-stationary millimeter wave (mmWave) geometry-based stochastic model for UAV to vehicle communication channels is proposed. Based on the analysis results of measured and ray tracing simulation data of UAV mmWave communication links, the proposed parametric channel model is constructed by a line-of-sight path, a ground specular path, and two strongest single-bounce paths. Meanwhile, a new parameter computation method is also developed, which is divided into the deterministic (or geometry-based) part and the random (or empirical) part. The simulated power delay profile and power angle profile demonstrate that the statistical properties of proposed channel model are time-variant with respect to the scattering scenarios, positions and beam direction. Moreover, the simulation results of autocorrelation functions fit well with the theoretical ones as well as the measured ones.

11.
J Transl Med ; 17(1): 193, 2019 06 10.
Artículo en Inglés | MEDLINE | ID: mdl-31182111

RESUMEN

BACKGROUND: Lymph node status and liver metastasis (LIM) are important in determining the prognosis of early colon carcinoma. We attempted to develop and validate nomograms to predict lymph node metastasis (LNM) and LIM in patients with early colon carcinoma. METHODS: A total of 32,819 patients who underwent surgery for pT1 or pT2 colon carcinoma were enrolled in the study based on their records in the SEER database. Risk factors for LNM and LIM were assessed based on univariate and multivariate binary logistic regression. The C-index and calibration plots were used to evaluate LNM and LIM model discrimination. The predictive accuracy and clinical values of the nomograms were measured by decision curve analysis. The predictive nomograms were further validated in the internal testing set. RESULTS: The LNM nomogram, consisting of seven features, achieved the same favorable prediction efficacy as the five-feature LIM nomogram. The calibration curves showed perfect agreement between nomogram predictions and actual observations. The decision curves indicated the clinical usefulness of the prediction nomograms. Receiver operating characteristic curves indicated good discrimination in the training set (area under the curve [AUC] = 0.667, 95% CI 0.661-0.673) and the testing set (AUC = 0.658, 95% CI 0.649-0.667) for the LNM nomogram and encouraging performance in the training set (AUC = 0.766, 95% CI 0.760-0.771) and the testing set (AUC = 0.825, 95% CI 0.818-0.832) for the LIM nomogram. CONCLUSION: Novel validated nomograms for patients with early colon carcinoma can effectively predict the individualized risk of LNM and LIM, and this predictive power may help doctors formulate suitable individual treatments.


Asunto(s)
Adenocarcinoma/diagnóstico , Neoplasias del Colon/diagnóstico , Detección Precoz del Cáncer/métodos , Neoplasias Hepáticas/diagnóstico , Metástasis Linfática/diagnóstico , Nomogramas , Adenocarcinoma/patología , Anciano , Anciano de 80 o más Años , Neoplasias del Colon/patología , Progresión de la Enfermedad , Femenino , Humanos , Neoplasias Hepáticas/secundario , Ganglios Linfáticos/patología , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Pronóstico , Estudios Retrospectivos , Factores de Riesgo
12.
Eur Heart J ; 38(9): 675-686, 2017 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-26491108

RESUMEN

AIMS: Congenital anomalies of arterial valves are common birth defects, leading to valvar stenosis. With no pharmaceutical treatment that can prevent the disease progression, prosthetic replacement is the only choice of treatment, incurring considerable morbidity and mortality. Animal models presenting localized anomalies and stenosis of congenital arterial valves similar to that of humans are critically needed research tools to uncover developmental molecular mechanisms underlying this devastating human condition. METHODS AND RESULTS: We generated and characterized mouse models with conditionally altered Notch signalling in endothelial or interstitial cells of developing valves. Mice with inactivation of Notch1 signalling in valvar endothelial cells (VEC) developed congenital anomalies of arterial valves including bicuspid aortic valves and valvar stenosis. Notch1 signalling in VEC was required for repressing proliferation and activating apoptosis of valvar interstitial cells (VIC) after endocardial-to-mesenchymal transformation (EMT). We showed that Notch signalling regulated Tnfα expression in vivo, and Tnf signalling was necessary for apoptosis of VIC and post-EMT development of arterial valves. Furthermore, activation or inhibition of Notch signalling in cultured pig aortic VEC-promoted or suppressed apoptosis of VIC, respectively. CONCLUSION: We have now met the need of critical animal models and shown that Notch-Tnf signalling balances proliferation and apoptosis for post-EMT development of arterial valves. Our results suggest that mutations in its components may lead to congenital anomaly of aortic valves and valvar stenosis in humans.


Asunto(s)
Estenosis de la Válvula Aórtica/etiología , Receptor Notch1/metabolismo , Animales , Válvula Aórtica/anomalías , Estenosis de la Válvula Aórtica/embriología , Estenosis de la Válvula Aórtica/fisiopatología , Apoptosis/fisiología , Modelos Animales de Enfermedad , Células Endoteliales/metabolismo , Células Endoteliales/fisiología , Homeostasis/fisiología , Células Madre Mesenquimatosas/fisiología , Ratones Noqueados , Receptores del Factor de Necrosis Tumoral/metabolismo , Transducción de Señal/fisiología , Factor de Necrosis Tumoral alfa/metabolismo
13.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 49(3): 380-383, 2018 May.
Artículo en Zh | MEDLINE | ID: mdl-30014638

RESUMEN

OBJECTIVE: To explore the effects of calcium pump inhibitor thapsigargin (TG) on intracellular Ca2+ and the expression of caspase-3 protein in mouse lung fibroblast. METHODS: Mice lung fibroblast cells were divided into three groups: the blank control group,transforming growth factor-ß1 (TGF-ß1) group and TG treated group. The cells were induced by 5 ng/mL TGF-ß1 for 24 h in TGF-ß1 group and TG group,4 µmol/L TG was added in TG group for 24 h. After 48 h,the cells were collected,and the cell structure was observed by transmission electron microscope,intracellular Ca2+ level was detected with laser confocal microscope,the protein expression of caspase-3 was examined using immunohistochemistry method. RESULTS: Transmission electron microscopy showed that the cells in the blank control group had obvious nucleolus,complete organelles and less apoptosis. In TGF-ß1 group,the cell morphology was intact,chromatin was evenly distributed,and no apoptotic cells were found. In TG group,there were a large number of apoptosis of fibroblasts,chromatin clumps in nuclei and a small amount of collagen fibers. The level of Ca2+ in TGF-ß1 group was significantly lower than that in control group (P<0.05),and which in TG group was significantly higher (P<0.05 ). The protein expression of caspase-3 in TGF-ß1 group were significantly lower than that in blank control group (P<0.05),which in TG group increased obviously (P<0.05). CONCLUSION: TG could cause intracellular calcium dysregulation in mouse lung fibroblasts,increase caspase-3 protein expression and promote cell apoptosis.


Asunto(s)
Caspasa 3/metabolismo , Fibroblastos/efectos de los fármacos , Tapsigargina/farmacología , Animales , Apoptosis , Calcio/metabolismo , Células Cultivadas , Pulmón/citología , Ratones , ARN Mensajero , Factor de Crecimiento Transformador beta1/farmacología
14.
Proc Natl Acad Sci U S A ; 111(47): 16889-94, 2014 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-25385587

RESUMEN

Although dominant gain-of-function triplet repeat expansions in the Huntingtin (HTT) gene are the underlying cause of Huntington disease (HD), understanding the normal functions of nonmutant HTT protein has remained a challenge. We report here findings that suggest that HTT plays a significant role in selective autophagy. Loss of HTT function in Drosophila disrupts starvation-induced autophagy in larvae and conditional knockout of HTT in the mouse CNS causes characteristic cellular hallmarks of disrupted autophagy, including an accumulation of striatal p62/SQSTM1 over time. We observe that specific domains of HTT have structural similarities to yeast Atg proteins that function in selective autophagy, and in particular that the C-terminal domain of HTT shares structural similarity to yeast Atg11, an autophagic scaffold protein. To explore possible functional similarity between HTT and Atg11, we investigated whether the C-terminal domain of HTT interacts with mammalian counterparts of yeast Atg11-interacting proteins. Strikingly, this domain of HTT coimmunoprecipitates with several key Atg11 interactors, including the Atg1/Unc-51-like autophagy activating kinase 1 kinase complex, autophagic receptor proteins, and mammalian Atg8 homologs. Mutation of a phylogenetically conserved WXXL domain in a C-terminal HTT fragment reduces coprecipitation with mammalian Atg8 homolog GABARAPL1, suggesting a direct interaction. Collectively, these data support a possible central role for HTT as an Atg11-like scaffold protein. These findings have relevance to both mechanisms of disease pathogenesis and to therapeutic intervention strategies that reduce levels of both mutant and normal HTT.


Asunto(s)
Autofagia , Proteínas Asociadas a Microtúbulos/fisiología , Animales , Animales Modificados Genéticamente , Drosophila , Proteínas de Drosophila , Proteína Huntingtina , Ratones , Proteínas Asociadas a Microtúbulos/genética
15.
Breast Cancer Res Treat ; 156(1): 149-62, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26902609

RESUMEN

Estrogen receptor (ER)-ß has been discovered for decades; however, its prognostic value in breast cancer patients remains controversial. We aimed to evaluate the impact of ER-ß expression on breast cancer survival. A systematic search of Medline, Embase, and Cochrane Library was performed to identify the association between ER-ß expression and outcomes in early breast cancer patients. Random-effects meta-analysis was conducted to generate combined hazard ratios (HRs) with 95 % confidence intervals (CIs) for overall survival (OS) and disease-free survival (DFS). A total of 6769 patients for ER-ß1, 2295 patients for ER-ß2, and 2271 patients for ER-ß5 from 21 studies were included. ER-ß1 protein expression was correlated with both favorable 5-year DFS and OS (HR 0.690, 95 % CI 0.610-0.779; P < 0.001; HR 0.632, 95 % CI 0.533-0.749; P < 0.001), while ER-ß1 mRNA had no significant association with DFS (HR 0.915, 95 % CI 0.581-1.440, P = 0.700). ER-ß2 protein was associated with improved DFS (HR 0.799, 95 % CI 0.644-0.992; P = 0.042), but not OS (HR 0.958, 95 % CI 0.762-1.205; P = 0.712). ER-ß5 protein was not significantly associated with DFS (HR 1.070, 95 % CI 0.810-1.410; P = 0.642). Subgroup analysis showed that higher ER-ß1 expression was associated with better 5-year DFS in both ER-α positive and negative patients, but the positive association between ER-ß1 expression and 5-year OS was only seen in ER-α positive patients. Wild-type ER-ß (ER-ß1) and its variant ER-ß2 protein expressions are associated with better survival in early breast cancer patients. The prognostic significance of ER-ß1 for DFS is independent of ER-α coexpression, whereas the impact on OS was only in ER-α positive breast cancer.


Asunto(s)
Neoplasias de la Mama/patología , Receptor beta de Estrógeno/genética , Receptor beta de Estrógeno/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Empalme Alternativo , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Supervivencia sin Enfermedad , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Persona de Mediana Edad , Pronóstico , Modelos de Riesgos Proporcionales , Análisis de Supervivencia
16.
J Gastroenterol Hepatol ; 31(2): 417-26, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26250532

RESUMEN

BACKGROUND AND AIM: Lymph node metastasis is a major prognostic factor for perihilar cholangiocarcinoma (PHC). However, prognostic significance of extent of node dissection, lymph node ratio (LNR), and number and location of positive nodes remain unclear. We aimed to evaluate whether node status, LNR, or number or location of positive nodes are independent factors for staging in PHC and to determine the minimum requirements for node examination. METHODS: The Surveillance, Epidemiology, and End Results database was used to identify 1116 resected PHCs from 1998 to 2008. The correlation between nodal status and survival was analyzed retrospectively. RESULTS: Lymph node metastasis occurred in 43.4% patients and was an independent predictor for overall survival and cancer-specific survival. No survival benefit was observed for an increasing number of node retrieval in node-positive patients. However, in node-negative patients, ≥13 node dissection was of more survival benefit than 3 ≤ total lymph node count (TLNC) ≤ 12 and TLNC < 3 (5-year overall survival: 52.8% vs 39.7% vs 26.3%, P = 0.001; 5-year cancer-specific survival: 60.6% vs 46.3% vs 30.0%, P = 0.001). No difference in survival between patients with regional and distant node involvement was found. Survival for patients with greater than three positive nodes was significantly worse than that for those with three or less (relative ratio: 1.466, P = 0.001). And patients with LNR > 0.27 also had unfavorable prognosis (relative ratio: 1.376, P = 0.001). CONCLUSIONS: We determined that to adequately assess nodal status of this life-threatening disease, 13 or more nodes retrieval should be considered. Number of positive nodes and LNR rather than location of metastatic nodes may be defined as parameters for staging of PHC.


Asunto(s)
Neoplasias de los Conductos Biliares/cirugía , Tumor de Klatskin/cirugía , Escisión del Ganglio Linfático , Anciano , Neoplasias de los Conductos Biliares/mortalidad , Neoplasias de los Conductos Biliares/patología , Neoplasias de los Conductos Biliares/terapia , Femenino , Humanos , Tumor de Klatskin/mortalidad , Tumor de Klatskin/secundario , Tumor de Klatskin/terapia , Metástasis Linfática , Masculino , Estadificación de Neoplasias , Pronóstico , Radioterapia Adyuvante/mortalidad , Programa de VERF , Tasa de Supervivencia
17.
Proc Natl Acad Sci U S A ; 110(31): E2875-84, 2013 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-23858448

RESUMEN

Macroautophagy (hereafter autophagy) functions in the nonselective clearance of cytoplasm. This process participates in many aspects of cell physiology, and is conserved in all eukaryotes. Autophagy begins with the organization of the phagophore assembly site (PAS), where most of the AuTophaGy-related (Atg) proteins are at least transiently localized. Autophagy occurs at a basal level and can be induced by various types of stress; the process must be tightly regulated because insufficient or excessive autophagy can be deleterious. A complex composed of Atg17-Atg31-Atg29 is vital for PAS organization and autophagy induction, implying a significant role in autophagy regulation. In this study, we demonstrate that Atg29 is a phosphorylated protein and that this modification is critical to its function; alanine substitution at the phosphorylation sites blocks its interaction with the scaffold protein Atg11 and its ability to facilitate assembly of the PAS. Atg29 has the characteristics of an intrinsically disordered protein, suggesting that it undergoes dynamic conformational changes on interaction with a binding partner(s). Finally, single-particle electron microscopy analysis of the Atg17-Atg31-Atg29 complex reveals an elongated structure with Atg29 located at the opposing ends.


Asunto(s)
Autofagia/fisiología , Proteínas Portadoras/metabolismo , Complejos Multiproteicos/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Proteínas de Transporte Vesicular/metabolismo , Proteínas Relacionadas con la Autofagia , Proteínas Portadoras/genética , Complejos Multiproteicos/genética , Complejos Multiproteicos/ultraestructura , Fosforilación/fisiología , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/ultraestructura , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Transporte Vesicular/genética
18.
AAPS PharmSciTech ; 17(3): 757-66, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26340950

RESUMEN

To enhance the stability of coenzyme Q10 (CoQ10), Kolliphor® HS 15 (HS15) was employed as a carrier to build up a stable CoQ10-loaded micelle delivery system. The impact of micellar compositions, the preparation condition, and the preparation method on size characteristics, the solubilization efficiency, and micellar stability were investigated. The optimal preparation conditions were 1:6, 4, 0.2%, 118°C, and 25 min for CoQ10/HS15 mass ratio, pH value, the concentration of glucose, and the sterilization conditions. Upon these conditions, the particle size, polydispersity index (PDI), zeta potential, the entrapment efficiency, drug loading, and the critical micelle concentration (CMC) of CoQ10-loaded micelles were 19.76 nm, 0.112, -3.405 mV, 99.39%, 13.77%, and 5.623 × 10(-4) g/mL, respectively. Differential scanning calorimetry (DSC) analysis collectively corroborated that CoQ10 was entrapped into the micelles in amorphous form. The release pattern of drug was analyzed and proved to follow the first order. Additionally, the samples were exposed to the temperatures of 30°C for 6 months with more significant impact on their stabilities as compared to 4 and 25°C based on particle size and PDI. Under constant humidity with light protection long-term (25 ± 2°C, relative humidity (RH) 60 ± 10%, 18 months) conditions, there was no variation except minor changes of CoQ10 content of the samples. The shelf life of the micellar samples could be predicted as 24 months based on the stability results. Consequently, the CoQ10-loaded micelles showed excellent stabilities below 25°C as a potential drug candidate for further clinical applications.


Asunto(s)
Sistemas de Liberación de Medicamentos/métodos , Micelas , Polietilenglicoles/administración & dosificación , Estearatos/administración & dosificación , Ubiquinona/análogos & derivados , Animales , Química Farmacéutica , Estabilidad de Medicamentos , Eritrocitos/efectos de los fármacos , Eritrocitos/fisiología , Polietilenglicoles/química , Polietilenglicoles/farmacocinética , Conejos , Estearatos/química , Estearatos/farmacocinética , Ubiquinona/administración & dosificación , Ubiquinona/química , Ubiquinona/farmacocinética
19.
AAPS PharmSciTech ; 17(6): 1376-1382, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26753818

RESUMEN

A critical issue for alcohol-induced liver disease (ALD) therapeutics is the lack of a highly efficient delivery system. In this study, a Puerarin-propylene glycol-liposome system was prepared for the purpose of targeting puerarin, an isoflavon, to the liver. Transmission electron microscope (TEM) results showed the liposomes to be spherical in shape with an average diameter of 182 nm with a polydispersity index of 0.239. The zeta potential of the particles was about -30 mV. The entrapment efficiency of puerarin was above 90%. MTT-based assay in HpeG2 cells showed no significant cytotoxicity in the presence of up to 25% concentration of the system containing 3% puerarin. In vivo performance of this system was studied in mice. Pharmacokinetics and distribution of puerarin-PG-liposome system was studied relative to puerarin solution at the same dose levels. The results show that puerarin-PG-liposome prolonged drug retention time and decreased elimination of puerarin in mice (AUC of liposome system and solution was 9.5 and 4.0 mg h L-1, respectively). Furthermore, propylene glycol (PG)-liposome system enhanced puerarin distribution into liver and spleen, while decreasing puerarin distribution in other tissues. Overall, the puerarin-PG-liposome system showed enhanced therapeutic effect in mice with ALD.


Asunto(s)
Enfermedad Hepática Inducida por Sustancias y Drogas/tratamiento farmacológico , Isoflavonas/química , Isoflavonas/farmacología , Liposomas/química , Hígado/efectos de los fármacos , Propilenglicol/química , Animales , Línea Celular Tumoral , Sistemas de Liberación de Medicamentos/métodos , Etanol/efectos adversos , Células Hep G2 , Humanos , Isoflavonas/farmacocinética , Hígado/metabolismo , Ratones , Tamaño de la Partícula , Bazo/metabolismo , Distribución Tisular
20.
Breast Cancer Res Treat ; 150(2): 439-45, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25764167

RESUMEN

Estrogen receptor (ER)-positive breast cancer patients treated with tamoxifen are known to have an elevated risk of subsequent endometrial cancer. However, it is unclear if ER-negative patients also have a higher risk of endometrial cancer. This population-based study aims to evaluate whether breast cancer patients with distinctive ER and PR status possess differential risks in developing delayed endometrial malignancy. Data were obtained from the Surveillance, Epidemiology, and End Results program (1992-2009). Standardized incidence ratio (SIR) was calculated as the observed cases of endometrial cancers among breast cancer survivors compared with the expected cases in the general population. Data were stratified by latency periods, race, age, and calendar year of breast cancer diagnosis. We identified 2044 patients who developed a second primary endometrial cancer among 289,933 breast cancer survivors. The overall SIRs for subsequent endometrial cancers were increased in all of the four subtypes (ER+PR+, ER+PR-, ER-PR+, and ER-PR-) of breast cancer. SIR was increased for all latency periods except for the initial 6-11 months after breast cancer diagnosis. Stratifying by age of diagnosis, elevated SIRs in all ER/PR groups were statistically significant among patients diagnosed with breast cancer after the age of 40. Demographically, non-Hispanic whites had increased SIRs in all subtypes of breast cancer, while Hispanic whites had no statistically elevated SIRs. Here we showed that patients with invasive breast cancer have a higher risk of developing subsequent endometrial cancer regardless of ER or PR status. The increased risk among hormone receptor-negative breast cancer survivors raises concerns whether common etiological factors among these breast cancer subtypes increase the susceptibility to develop endometrial cancer. Lower threshold for routine endometrial cancer surveillance may be warranted.


Asunto(s)
Neoplasias de la Mama/metabolismo , Neoplasias Endometriales/metabolismo , Neoplasias Primarias Secundarias/metabolismo , Receptores de Estrógenos/metabolismo , Receptores de Progesterona/metabolismo , Adulto , Anciano , Neoplasias de la Mama/patología , Femenino , Humanos , Incidencia , Persona de Mediana Edad , Factores de Riesgo , Programa de VERF , Sobrevivientes , Adulto Joven
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