Downregulation of NUP93 aggravates hypoxia-induced death of cardiomyocytes in vitro through abnormal regulation of gene transcription.

Nuclear pore complex in the nuclear envelope plays an important role in controlling the transportation of RNAs, proteins and other macromolecules between the nucleus and cytoplasm. The relationship between abnormal expression of nucleoporins and cardiovascular diseases is unclear. In this study we investigated how myocardial infarction affected the expression and function of nucleoporins in cardiomyocytes. We separately knocked down 27 nucleoporins in rat primary myocardial cells. Among 27 nucleoporins, knockdown of Nup93, Nup210 and Nup214 markedly increased the expression of ANP and BNP, two molecular markers of cardiomyocyte function. We showed that Nup93 was significantly downregulated in hypoxic cardiomyocytes. Knockdown of Nup93 aggravated hypoxia-induced injury and cell death of cardiomyocytes, whereas overexpression of Nup93 led to the opposite effects. RNA-seq and bioinformatics analysis revealed that knockdown of Nup93 did not affect the overall transportation of mRNAs from the nucleus to the cytoplasm, but regulated the transcription of a large number of mRNAs in cardiomyocytes, which are mainly involved in oxidative phosphorylation and ribosome subunits. Most of the down-regulated genes by Nup93 knockdown overlapped with the genes whose promoters could be directly bound by Nup93. Among these genes, we demonstrated that Nup93 knockdown significantly down-regulated the expression of YAP1. Overexpression of YAP1 partially rescued the function of Nup93 knockdown and attenuated the effects of hypoxia on cell injury and cardiomyocyte death. We conclude that down-regulation of Nup93, at least partially, contributes to hypoxia-induced injury and cardiomyocyte death through abnormal interaction with the genome to dynamically regulate the transcription of YAP1 and other genes. These results reveal a new mechanism of Nup93 and might provide new therapeutic targets for the treatment of ischemia-induced heart failure.

Cardiovascular-specific PSEN1 deletion leads to abnormalities in calcium homeostasis.

Mutations of PSEN1 have been reported in dilated cardiomyopathy pedigrees. Understanding the effects and mechanisms of PSEN1 in cardiomyocytes might have important implications for treatment of heart diseases. Here, we showed that PSEN1 was downregulated in ischemia-induced failing hearts. Functionally, cardiovascular specific PSEN1 deletion led to spontaneous death of the mice due to cardiomyopathy. At the age of 11 months, the ratio of the heart weight/body weight was slightly lower in the Sm22a-PSEN1-KO mice compared with that of the WT mice. Echocardiography showed that the percentage of ejection fraction and fractional shortening was significantly reduced in the Sm22a-PSEN1-KO group compared with the percent of these measures in the WT group, indicating that PSEN1-KO resulted in heart failure. The abnormally regulated genes resulted from PSEN1-KO were detected to be enriched in muscle development and dilated cardiomyopathy. Among them, several genes encode Ca2+ ion channels, promoting us to investigate the effects of PSEN1 KO on regulation of Ca2+ in isolated adult cardiomyocytes. Consistently, in isolated adult cardiomyocytes, PSEN1-KO increased the concentration of cytosolic Ca2+ and reduced Ca2+ concentration inside the sarcoplasmic reticulum (SR) lumen at the resting stage. Additionally, SR Ca2+ was decreased in the failing hearts of WT mice, but with the lowest levels observed in the failing hearts of PSEN1 knockout mice. These results indicate that the process of Ca2+ release from SR into cytoplasm was affected by PSEN1 KO. Therefore, the abnormalities in Ca2+ homeostasis resulted from downregulation of PSEN1 in failing hearts might contribute to aging-related cardiomyopathy, which might had important implications for the treatment of aging-related heart diseases.

Conditionally targeted deletion of PSEN1 leads to diastolic heart dysfunction.

Recently, PSEN1 has been reported to have mutations in dilated cardiomyopathy pedigrees. However, the function and mechanism of PSEN1 in cardiomyopathy remains unresolved. Here, we established four types of genetically modified mice to determine the function of PSEN1 in cardiac development and pathology. PSEN1 null mutation resulted in perinatal death, retardation of heart growth, ventricular dilatation, septum defects, and valvular thickening. PSEN1 knockout in adults led to decreased muscle fibers, widened sarcomere Z lines and reduced lengths of sarcomeres in cardiomyocytes. Cardiovascular loss of function of PSEN1 induced by Sm22a-Cre or Myh6-Cre/ER/tamoxifen also resulted in severe ultrastructural abnormalities, such as relaxed gap junctions between neighboring cardiomyocytes. Functionally, cardiovascular deletion of PSEN1 caused spontaneous mortality from birth to adulthood and led to diastolic heart dysfunction, including decreased volume of the left ventricle at the end-systolic and end-diastolic stages. Additionally, in a myocardial ischemia model, deletion of PSEN1 in the cardiovascular system first protected mice by inducing adaptive hypertrophy but ultimately resulted in severe heart failure. Furthermore, a collection of genes was abnormally expressed in the hearts of cardiac-specific PSEN1 knockout mice. They were enriched in cell proliferation, calcium regulation, and so on. Taken together, dynamic regulation and abnormal function of PSEN1 underlie the pathogenesis of cardiovascular diseases due to ultrastructural abnormality of cardiomyocytes.

Plasma miR-451 with echocardiography serves as a diagnostic reference for pulmonary hypertension.

Due to the lack of typical clinical symptoms, the average delay time for diagnosis of pulmonary hypertension (PH) is longer than 2 years. It is urgent to find biomarkers for PH diagnosis. In this study we investigated whether plasma microRNAs (miRNAs) can be used as biomarkers for PH diagnosis. We used microarray to identify dynamic miRNAs between PH and non-PH patients. The candidate miRNAs were verified using qRT-PCR in a mouse model of PH, which was induced by monocrotaline (MCT) injection. We observed that miR-21, miR-126, miR-145, miR-191 and miR-150 had no differences between control mice and MCT-treated mice; but plasma miR-451 was significantly decreased in the 2wk-MCT group, with no further decrease in the 4wk-MCT group. Plasma miR-451 was also markedly decreased in PH patients, whereas miR-21, miR-126, miR-150 and miR-320 did not show differences between 53 PH patients and 54 non-PH patients. Receiver operating characteristic curves (ROCs) were constructed from the patient data to assess the clinical diagnostic values of circulating miR-451 and Doppler echocardiography (D-ECHO). The areas under the curve (AUCs) of ROCs for miR-451 and D-ECHO were 0.710 and 0.766, respectively. Combination of miR-451 and D-ECHO with AUC of 0.825 was superior to the use of either miR-451 or D-ECHO alone for PH diagnosis. In conclusion, plasma miR-451 has a moderate diagnostic value in PH comparable to that of D-ECHO, and the combination of miR-451 with D-ECHO has better diagnostic value than either method alone, which may have implications for PH diagnosis.

Out-of-Band Radiation and Spatio-Temporal Characterization of Gd Target Laser Plasma Sources.

In this paper, an Nd∶YAG laser with 10ns pulse width and output wavelength of 1 064 nm was employed to ablate Gd metal target and Gd-doped glass target for plasma generation. The out-of-band (OOB) radiation of extreme ultraviolet sources with the two target configurations was comparatively studied. It has been found that the continuous radiation emitted by the plasma is the main component of the out-of-band radiation. The spectral distribution of the continuum emission matches that of blackbody radiation with a temperature of about 5 eV. And it is also found that the intensity of OOB radiation can be considerably decreased by using Gd-doped glass target. Optical Emission Spectroscopy (OES) has been used to analyze the temporal and spatial behaviors of electron temperature (Te) and density (Ne) of the Gd-doped glass target plasma, and experimental results show that temporal evolution of electron temperature and density of the plasma are found to be decayed exponentially with the increasing of delay time. At 125 ns after laser irradiation, electron temperature and density were 4 eV and 1.2×1018 cm-3 respectively, and then decreased to 1.5 eV and 8×1017 cm-3 with delaying time of 250 ns. On the other hand, spatial evolution of electron temperature and density show that both of them first increase and then decrease in the region of 1~10 mm from the target surface. The electron temperature and electron density achieves the maximum of 2.6 eV and 8.5×1017 cm-3, respectively, when the probe location away from the target surface 6 mm.

[Analysis of arsenic speciation in food condiments based on the online trapping/separation coupling system].

An online coupling system based on gas chromatography-hydride generation with atomic fluorescence spectrometry (GC-HG-AFS) for the analysis of arsenic species in food seasoning(soy sauce and vinegar) was developed. With absorbent cotton as separation medium, the volatile arsenic species released from the samples were cold trapped online by liquid nitrogen. Then, the baseline separation of the volatile arsenic species was achieved at the room temperature and the arsenic species were sensitively detected by atomic fluorescence spectrophotometer. The experimental conditions such as flow rates of carrier .gas (He), acid type and concentration, reducing reagent concentration and reaction time were discussed. Under the optimum conditions, the limit of detection for As(III), As(V), MMA(V) and DMA(V) was 0.2, 0.2, 0.3 and 0.8 ng x mL(-1), respectively. The recoveries of As(III), As(V), MMA(V) and DMA(V) in soy sauce and vinegar were 93.07%-103.54%. Compared with the traditional liquid chromatography separation algorithm, the method was rapid, sensitive without any complex sample pretreatment. It was suitable and practical for detection of arsenic especially inorganic arsenic in food seasoning.

Abnormal expression of PRKAG2-AS1 in endothelial cells induced inflammation and apoptosis by reducing PRKAG2 expression.

PRKAG2 is required for the maintenance of cellular energy balance. PRKAG2-AS1, a long non-coding RNA (lncRNA), was found within the promoter region of PRKAG2. Despite the extensive expression of PRKAG2-AS1 in endothelial cells, the precise function and mechanism of this gene in endothelial cells have yet to be elucidated. The localization of PRKAG2-AS1 was predominantly observed in the nucleus, as revealed using nuclear and cytoplasmic fractionation and fluorescence in situ hybridization. The manipulation of PRKAG2-AS1 by knockdown and overexpression within the nucleus significantly altered PRKAG2 expression in a cis-regulatory manner. The expression of PRKAG2-AS1 and its target genes, PRKAG2b and PRKAG2d, was down-regulated in endothelial cells subjected to oxLDL and Hcy-induced injury. This finding suggests that PRKAG2-AS1 may be involved in the mechanism behind endothelial injury. The suppression of PRKAG2-AS1 specifically in the nucleus led to an upregulation of inflammatory molecules such as cytokines, adhesion molecules, and chemokines in endothelial cells. Additionally, this nuclear suppression of PRKAG2-AS1 facilitated the adherence of THP1 cells to endothelial cells. We confirmed the role of nuclear knockdown PRKAG2-AS1 in the induction of apoptosis and inhibition of cell proliferation, migration, and lumen formation through flow cytometry, TUNEL test, CCK8 assay, and cell scratching. Finally, it was determined that PRKAG2-AS1 exerts direct control over the transcription of PRKAG2 by its binding to their promoters. In conclusion, downregulation of PRKAG2-AS1 suppressed the proliferation and migration, promoted inflammation and apoptosis of endothelial cells, and thus contributed to the development of atherosclerosis resulting from endothelial cell injury.

[Health Impact Analysis of Fine Particulate Pollution from Vehicles in the Beijing-Tianjin-Hebei Region].

Vehicle exhaust emissions are posing an increasingly adverse impact on urban air quality. The emission characteristics analysis and health effect assessment of specific air pollution sources can provide scientific evidence for environmental air quality management. The characteristics and health effects of PM2.5 emissions from vehicles and economic losses caused by them in the Beijing-Tianjin-Hebei Region were analyzed from 2010 to 2020. From 2010 to 2020, PM2.5 emissions from vehicles in the Beijing-Tianjin-Hebei Region showed an annual increase at first, followed by a slow decrease. According to the emission sharing ratios of different vehicle types, heavy-duty trucks and buses were the main contributors to PM2.5, with a total contribution rate of over 65.27%. The emission characteristics of vehicle pollutants varied in different cities. The contribution rate of pollutants in Beijing decreased significantly, and the emission reduction in other cities was also dramatic. The evaluation results of the impact of PM2.5 emissions from vehicles on human health showed that the number of health endpoints in the Beijing-Tianjin-Hebei Region was on the rise. In 2020, PM2.5 pollution caused approximately 34337 premature deaths (95% CI:9025-57209), 45500 hospitalizations (95% CI:10800-80200), 282300 outpatients (95% CI:140500-416300), and 439000 people to fall ill (95% CI:160300-679200). Beijing had the largest number of patients that presented different health endpoints. The total health and economic losses caused by PM2.5 emissions from vehicles in 2010, 2015, and 2020 were 27.742 billion yuan (95% CI:8.616-44.643 billion yuan), 90.608 billion yuan (95% CI:28.476-144.050 billion yuan), and 129.965 billion yuan (95% CI:40.829-205.245 billion yuan), respectively. In addition, due to the differences in vehicle ownership, PM2.5 concentrations, population, and economic losses per case of health outcome, the health effects and economic losses varied in different cities within the region. Among these cities, Beijing, Tianjin, Baoding, and Tangshan were at higher health risks and suffered more economic losses. The results of this study will help reduce the adverse effects on health and economic losses caused by pollution discharge and provide scientific evidence for environmental protection authorities to implement targeted pollution prevention and control.

Abnormal expression of PRKAG2-AS results in dysfunction of cardiomyocytes through regulating PRKAG2 transcription by interacting with PPARG.

The role of PRKAG2 in the maintenance of heart function is well established, but little is known about how PRKAG2 is regulated in cardiomyocytes. In this study, we investigated the role of the lncRNA PRKAG2-AS, which is present at the PRKAG2 promoter, in the regulation of PRKAG2 expression. PRKAG2-AS expression was predominantly nuclear, as determined by RNA nucleoplasmic separation and fluorescence in situ hybridization. Knockdown of PRKAG2-AS in the nucleus, but not the cytoplasm, significantly decreased the expression of PRKAG2b and PRKAG2d. Interestingly, we found that PRKAG2-AS and its target genes, PRKAG2b and PRKAG2d, were reduced in the hearts of patients with ischemic cardiomyopathy, suggesting a potential role for PRKAG2-AS in myocardial ischemia. Indeed, knockdown of PRKAG2-AS in the nucleus resulted in apoptosis of cardiomyocytes. We further elucidated the mechanism by which PRKAG2-AS regulates PRKAG2 transcription by identifying 58 PRKAG2-AS interacting proteins. Among them, PPARG was selected for further investigation based on its correlation and potential interaction with PRKAG2-AS in regulating transcription. Overexpression of PPARG, or its activation with rosiglitazone, led to a significant increase in the expression of PRKAG2b and PRKAG2d in cardiomyocytes, which could be attenuated by PRKAG2-AS knockdown. This finding suggests that PRKAG2-AS mediates, at least partially, the protective effects of rosiglitazone on hypoxia-induced apoptosis. However, given the risk of rosiglitazone in heart failure, we also examined the involvement of PRKAG2-AS in this condition and found that PRKAG2-AS, as well as PRKAG2b and PRKAG2d, was elevated in hearts with dilated cardiomyopathy (DCM) and that overexpression of PRKAG2-AS led to a significant increase in PRKAG2b and PRKAG2d expression, indicating that up-regulation of PRKAG2-AS may contribute to the mechanism of heart failure by promoting transcription of PRKAG2. Consequently, proper expression of PRKAG2-AS is essential for maintaining cardiomyocyte function, and aberrant PRKAG2-AS expression induced by hypoxia or other stimuli may cause cardiac dysfunction.

Attenuation of microRNA-22 derepressed PTEN to effectively protect rat cardiomyocytes from hypertrophy.

Cardiac hypertrophy, which is characterized by the enlargement of cell size, reactivation of fetal genes, remains one of the most important triggers to heart failure. Increasing evidence shows that microRNA (miRNA) is extensively involved in the pathogenesis of cardiac hypertrophy. But the effects of miRNAs on cardiomyocyte hypertrophy have not been completely solved yet. Here, we showed that a collection of miRNAs was aberrantly expressed in hypertrophic cardiomyocytes induced by phenylephrine (PE) or angiotensin II (Ang II). Among them, miR-22 was the most strikingly up-regulated miRNA. To investigate the role of miR-22 in hypertrophy, both over-expression and knock-down assays were performed on cardiomyocytes. The results showed that up-regulation of miR-22 significantly increased the cell size and markedly influenced the expression of hypertrophic markers, including induction of nppa and reduction of myh6. In contrast, reduction of miR-22 level attenuated either PE- or Ang II-induced hypertrophic reaction. Furthermore, several genes, including PTEN, were identified as potential targets of miR-22 by bioinformatic algorithms. Using luciferase analysis, miR-22 could significantly suppress the luciferase activity of reporter fused with 3' untranslated region of PTEN mRNA. Furthermore, up-regulation of miR-22 could suppress the protein level of PTEN and reduction of miR-22 level markedly increased the protein level of PTEN in cardiomyocytes by Western blot analysis, suggesting that the contribution of miR-22 to cardiomyocyte hypertrophy may be partially through targeting PTEN. Taken together, miRNAs were dynamically regulated in cardiomyocyte hypertrophy and attenuation of miR-22 in rat cardiomyocytes efficiently protected from hypertrophic effects through derepressing PTEN.

Overexpression of microRNA-378 attenuates ischemia-induced apoptosis by inhibiting caspase-3 expression in cardiac myocytes.

MicroRNAs (miRNAs) are a novel class of powerful, endogenous regulators of gene expression. In an intact rat model of myocardial ischemia caused by coronary artery ligation, this study identified 17 miRNAs that changed more than 1.5-fold in the myocardium subjected to 4-h ischemia. Using miRNA microarray analysis, most of these aberrantly expressed miRNAs were confirmed by quantitative RT-PCR. MiR-378, a significantly down-regulated miRNA, was selected for further function study. In serum deprived rat H9c2 cardiomyocytes exposed to hypoxia (1% O(2)), miR-378 expression was down-regulated as well. The overexpression of miR-378 resulting from miR-378 mimic transfection significantly enhanced cell viability, reduced lactate dehydrogenase release, and inhibited apoptosis and necrosis. By contrast, miR-378 deficiency resulting from miR-378 inhibitor transfection aggravated the hypoxia-induced apoptosis and cell injury. In accordance, miR-378 inhibitor caused significant apoptosis and cell injury to cardiomyocytes cultured under normoxia. Using bioinformatic algorithms, caspase-3, a key apoptosis executioner, was predicted as a putative target of miR-378. The quantitative RT-PCR showed no effects of miR-378 mimic or inhibitor on caspase-3 mRNA level. However, the amount of caspase-3 proteins was reduced by miR-378 mimic, whereas increased by miR-378 inhibitor. Furthermore, the luciferase reporter assay confirmed caspase-3 to be a target of miR-378, and the apoptosis and cell injury caused by miR-378 inhibitor in both normoxic and hypoxic cells were abolished by a caspase-3 inhibitor. This study first showed that miR-378 inhibited caspase-3 expression and attenuated ischemic injury in cardiomyocytes. It may represent a potential novel treatment for apoptosis and ischemic heart disease.

Attenuation of microRNA-1 derepresses the cytoskeleton regulatory protein twinfilin-1 to provoke cardiac hypertrophy.

MicroRNAs are involved in several aspects of cardiac hypertrophy, including cardiac growth, conduction, and fibrosis. However, their effects on the regulation of the cardiomyocyte cytoskeleton in this pathological process are not known. Here, with microRNA microarray and small RNA library sequencing, we show that microRNA-1 (miR-1) is the most abundant microRNA in the human heart. By applying bioinformatic target prediction, a cytoskeleton regulatory protein twinfilin-1 was identified as a potential target of miR-1. Overexpression of miR-1 not only reduced the luciferase activity of the reporter containing the 3' untranslated region of twinfilin-1 mRNA, but also suppressed the endogenous protein expression of twinfilin-1, indicating that twinfilin-1 is a direct target of miR-1. miR-1 was substantially downregulated in the rat hypertrophic left ventricle and phenylephrine-induced hypertrophic cardiomyocytes, and accordingly, the protein level of twinfilin-1 was increased. Furthermore, overexpression of miR-1 in hypertrophic cardiomyocytes reduced the cell size and attenuated the expression of hypertrophic markers, whereas silencing of miR-1 in cardiomyocytes resulted in the hypertrophic phenotype. In accordance, twinfilin-1 overexpression promoted cardiomyocyte hypertrophy. Taken together, our results demonstrate that the cytoskeleton regulatory protein twinfilin-1 is a novel target of miR-1, and that reduction of miR-1 by hypertrophic stimuli induces the upregulation of twinfilin-1, which in turn evokes hypertrophy through the regulation of cardiac cytoskeleton.

[Application of Pu isotope tracing technique in soil erosion research]. / PuåŒä½ç´ ç¤ºè¸ªæŠ€æœ¯åœ¨åœŸå£¤ä¾µèš€ç ”ç©¶ä¸­çš„åº”ç”¨.

As an essential form of material migration on the surface of the earth, soil erosion is one of the primary causes of soil fertility reduction and environmental degradation. Quantifying soil erosion rate is the precondition and foundation for regional soil erosion control. The Pu isotopes produced by atmospheric nuclear tests have a long half-life after settling into the soil and could be easily adsorbed by clay minerals and organic matter. In recent years, Pu isotopes have become principal trace elements in the quantitative studies of soil erosion rate, especially with the development of mass spectrometry technique. The measurement time of Pu isotopes has been shortened, and the sensitivity of Pu isotopes has been improved, both of which help improve the radionuclide tracing technology for soil erosion. Here, we summarized the distribution characteristics as well as the adsorption and migration behavior of Pu isotopes in soil. We described the basic principles for the application of Pu isotopes in tracing soil erosion, and elaborated the research progress concerning relevant applications. Moreover, we compared the applicability of Pu isotope and 137Cs tracing techniques in soil erosion research and proposed research directions in the future. This review would provide a reference for the scientific applications of Pu isotope tracing technique in soil erosion research.

[Effect of miRNA-199a on rat cardiac hypertrophy].

OBJECTIVE: To investigate the role of miRNA-199a on cardiac hypertrophy. METHODS: (1) Male Sprague-Dawley rats were subjected to pressure overload induced by abdominal aortic constriction (AAC, n = 6) and quantitative real-time polymerase chain reaction (qRT-PCR) was used to detect the change of microRNAs (miRNAs). (2) Neonatal rat ventricular myocytes were isolated from 2-day old Sprague-Dawley rats. The myocytes were divided into two groups: adenovirus miRNA-199a (Ad-miRNA-199a) or adenovirus vector (Ad-vector). They were transfected in cardiomyocytes for 48 h using Lipofectamine 2000. qRT-PCR was used to detect the change of myocardial hypertrophy markers α-myosin heavy chain (αMHC, myh6), ß-myosin heavy chain (ßMHC, myh7) and atrial natriuretic peptide (ANP, Nppa). Software Axio Vision was used to detect the change of cardiomyocytes surface areas. (3) Neonatal rat ventricular myocytes were divided into two groups: antisense oligonucleotide-miRNA-199a (As-miRNA-199a) and scramble oligonucleotides (As-ctl). They were transfected to cardiomyocytes respectively for 48 h. qRT-PCR was used to detect the change of miRNA-199a. (4) Neonatal rat ventricular myocytes were divided into four groups: A: control (ctl), B: phenylephrine (PE), C: PE + As-ctl, D: PE + As-miRNA-199a. qRT-PCR was used to detect the change of myh6, myh7 and Nppa. Software Axio Vision was used to detect the change of cardiomyocytes surface areas. RESULTS: (1) qRT-PCR results showed that miRNA-1, miRNA-133, miRNA-181a and miRNA-499 were significantly decreased, while the miRNA-199a was significantly increased at 1 week post AAC hearts compared with the sham group. (2) qRT-PCR results showed that miRNA-199a and myh7 were increased and myh6 was decreased significantly in Ad-miRNA-199a group compared with Ad-vector group. The cardiomyocytes surface area was increased in Ad-miRNA-199a group detected by immunofluorescence. (3) qRT-PCR results showed that miRNA-199a was significantly decreased in As-miRNA-199a group compared with Ad-vector group. (4) The Nppa and myh7 were significantly increased and myh6 was decreased in cardiomyocytes stimulated by PE for 48 h. The cardiomyocytes surface area determined by immunofluorescence was increased in PE + As-miRNA-199a groups compared with PE + As-ctl groups. CONCLUSION: miRNA-199a may play a regulatory role in cardiac hypertrophy.

MicroRNAs are dynamically regulated in hypertrophic hearts, and miR-199a is essential for the maintenance of cell size in cardiomyocytes.

Cardiac hypertrophy, which is characterized by an increase in cell size and reactivation of fetal genes, occurs as an adaptive response to diverse forms of stress and often results in heart failure and sudden death. Growing evidence indicates that microRNAs (miRNAs) are involved in cardiac hypertrophy, but the function of these miRNAs remains elusive. Here, using real time PCR analysis, we showed that several miRNAs were dynamically regulated in the rat hypertrophic hearts and miR-199a was up-regulated by 10-fold in hypertrophic hearts after abdominal aorta constriction for 12 weeks. With tissue profiling analysis, we showed that miR-199a was predominantly expressed in cardiomyocytes, but was also faintly detected in cardiac fibroblasts. To investigate whether miR-199a was involved in cardiac hypertrophy, both over-expression and knockdown of miR-199a were performed in cultured cardiomyocytes. Over-expression of miR-199a in cardiomyocytes increased the cell size as measured by cell surface area, and also reduced the mRNA expression level of alpha-myosin heavy chain. In accordance, knockdown of endogenous miR-199a in cardiomyocytes reduced the cell size. Down-regulation of miR-199a also attenuated the phenylephrine-induced increase of cell size. Furthermore, bioinformatic algorithms were used to predict the potential targets of miR-199a in cardiac hypertrophy, and hypoxia-inducible factor 1 alpha was confirmed by the luciferase reporter assay to be a potential target of miR-199a. Taken together, our results demonstrated that miR-199a, which was predominantly expressed in cardiomyocytes, was essential for the maintenance of cell size of cardiomyocytes and might play a role in the regulation of cardiac hypertrophy.

Light- and temperature-assisted spin state annealing: accessing the hidden multistability.

Among responsive multistable materials, spin crossover (SCO) systems are of particular interest for stabilizing multiple spin states with various stimulus inputs and physical outputs. Here, in a 2D Hofmann-type coordination polymer, [Fe(isoq)2{Au(CN)2}2] (isoq = isoquinoline), a medium-temperature annealing process is introduced after light/temperature stimulation, which accesses the hidden multistability of the spin state. With the combined effort of magnetic, crystallographic and Mössbauer spectral investigation, these distinct spin states are identified and the light- and temperature-assisted transition pathways are clarified. Such excitation-relaxation and trapping-relaxation joint mechanisms, as ingenious interplays between the kinetic and thermodynamic effects, uncover hidden possibilities for the discovery of multistable materials and the development of multistate intelligent devices.

Effects of time delays on the therapeutic outcomes of intravenous thrombolysis for acute ischemic stroke in the posterior circulation: An observational study.

OBJECTIVES: We aim to demonstrate the effects of time delays on the therapeutic outcomes of intravenous thrombolysis (IVT) in acute posterior circulation stroke (PCS) patients. METHODS: Consecutive PCS cases treated with IVT alone were retrospectively examined. The primary end point was set to be a favorable outcome (modified Rankin Scale [mRS] ≤2) at 3 months, and angiographic recanalization was set to be the secondary outcome. RESULTS: A total of 95 PCS cases with IVT were recruited. The patients with favorable outcomes and those without favorable outcomes had similar baseline characteristics, except for significantly lower National Institute of Health Stroke Scale (NIHSS) scores (5 vs. 12, respectively; p < 0.001) and less hyperdense basilar artery signs in head CTs (26.5% vs. 70.4%, respectively; p < 0.001) for those with favorable outcomes. For patients with an onset-to-treatment time (OTT) of 0-90 min (n = 5), 91-180 min (n = 38), 181-270 min (n = 37), or ≧271 min (n = 15), the rate of favorable outcome was 100.0%, 71.1%, 67.6%, or 73.3%, respectively, and the Cochran-Armitage trend test showed no linear trend between the OTT and the clinical prognosis of IVT in PCS (p = 0.501) patients. In addition, the rates of recanalization were 100.0%, 68.4%, 64.9%, and 46.7%, and the Cochran-Armitage trend test suggested a linear trend between the OTT and recanalization (p = 0.046); that is, the proportion of PCS patients who underwent recanalization decreased with increasing OTTs. In the multivariate logistic regression analysis, after adjusting for confounding factors with p â‰¦ 0.20 in the univariate analysis, baseline NIHSS scores and hyperdense basilar artery signs were negatively associated with favorable outcomes, with odds ratios (OR) of 0.884 (95% confidence interval [CI], 0.804-0.971; p = 0.010) and 0.208 (95% CI, 0.062-0.693; p = 0.011), respectively. In addition, there was a negative association between recanalization, OTTs (OR, 0.993, 95% CI, 0.987-0.999; p = 0.029), and baseline NIHSS scores (OR, 0.881, 95% CI, 0.802-0.967; p = 0.008). CONCLUSION: Irrespective of stroke severity, the therapeutic effects of recanalization after IVT decreased significantly with longer time delays in PCS patients.

Novel insight into the role of withering process in characteristic flavor formation of teas using transcriptome analysis and metabolite profiling.

Withering is an indispensable process for improving flavors in green, black and white teas during their manufacturing. The effects of the withering process on the formation of tea flavors were investigated using transcriptome and metabolite profiling in withered tea leaves. A total of 3268, 23,282 and 25,185 differentially expressed genes (DEGs) were identified at 3 h (68%, water content), 12 h (61%) and 24 h (48%) of the withering process, respectively. The DEGs, involved in flavonoid biosynthesis were significantly downregulated, which could be correlated with the reduction of catechins. Enhancement of terpenoids and alpha-linolenic acid metabolism could trigger an increase in the total content and number of volatiles. The increase in free amino acid-content could be related to 261 DEGs. Our study suggests that dehydration stress during withering induced significant changes in the gene transcription and content of the tea flavor compounds, which promoted the special flavors in various teas.

Identifying external nutrient reduction requirements and potential in the hypereutrophic Lake Taihu Basin, China.

Reducing external nutrient loads is the first step for controlling eutrophication. Here, we identified external nutrient reduction requirements and potential of strategies for achieving reductions to remediate a eutrophic water body, Lake Taihu, China. A mass balance approach based on the entire lake was used to identify nutrient reduction requirements; an empirical export coefficient approach was introduced to estimate the nutrient reduction potential of the overall program on integrated regulation of Taihu Lake Basin (hereafter referred to as the "Guideline"). Reduction requirements included external total nitrogen (TN) and total phosphorus (TP) loads, which should be reduced by 41-55 and 25-50%, respectively, to prevent nutrient accumulation in Lake Taihu and to meet the planned water quality targets. In 2010, which is the most seriously polluted calendar year during the 2008-2014 period, the nutrient reduction requirements were estimated to be 36,819 tons of N and 2442 tons of P, and the potential nutrient reduction strategies would reduce approximately 25,821 tons of N and 3024 tons of P. Since there is a net N remaining in the reduction requirements, it should be the focus and deserves more attention in identifying external nutrient reduction strategies. Moreover, abatement measures outlined in the Guideline with high P reduction potential required large monetary investments. Achieving TP reduction requirement using the cost-effective strategy costs about 80.24 million USD. The design of nutrient reduction strategies should be enacted according to regional and sectoral differences and the cost-effectiveness of abatement measures.

MicroRNA-199a acts as a potential suppressor of cardiomyocyte autophagy through targeting Hspa5.

Autophagy is an adaptive response to cardiomyocytes survival under stress conditions. MicroRNAs (miRNAs, miR) have been described to act as potent modulators of autophagy. To investigate whether and how miR-199a modulated autophagy in vitro, primary cardiomyocytes were treated under starvation to induce autophagy. Results showed that down-regulation of miR-199a was sufficient to activate cardiomyocytes autophagy. MiR-199a suppressed cardiomyocytes autophagy through direct inhibiting heat shock protein family A member 5 (Hspa5). Forced overexpression of Hspa5 recovered the inhibitory effect of miR-199a in autophagy activation. Our results suggested miR-199a as an effective suppressor of starvation-induced cardiomyocytes autophagy and that Hspa5 was a direct target during this process. These results extend the understanding of the role and pathway of miR-199a in cardiomyocytes autophagy, and may introduce a potential therapeutic strategy for the protection of cardiomyocytes in myocardial infarction or ischemic heart disease.