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1.
Life (Basel) ; 14(9)2024 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-39337852

RESUMEN

We assessed the feasibility of concurrent monitoring of cerebral hemodynamics in adult, comatose out-of-hospital cardiac arrest (OHCA) patients admitted to the National University Heart Centre Singapore from October 2021 to August 2023. Patients underwent continuous near-infrared spectroscopy (NIRS) monitoring in the first 72 h after return of spontaneous circulation (ROSC) and 30-min transcranial Doppler ultrasound (TCD) monitoring at least once. With constant mechanical ventilatory settings and continuous electrocardiographic, pulse oximeter and end-tidal carbon dioxide monitoring, blood pressure was manipulated via vasopressors and cerebral autoregulation assessed by measuring changes in regional cerebral oxygenation (NIRS) and cerebral blood flow velocities (TCD) in response to changes in mean arterial pressure. The primary outcome was neurological recovery at hospital discharge. Amongst the first 16 patients (median age 61, 94% males), we observed four unique patterns: preserved cerebral autoregulation, loss of cerebral autoregulation, cardio-cerebral asynchrony and cerebral circulatory arrest. Patients with preserved cerebral autoregulation had lower levels of neuro-injury biomarkers (neurofilaments light and heavy) and the majority (86%) were discharged with good neurological recovery. Multi-modal assessment of cerebral hemodynamics after OHCA is feasible and derived patterns correlated with neurological outcomes. The between- and within-patient heterogeneity in cerebral hemodynamics calls for more research on individualized treatment strategies.

2.
J Cardiovasc Dev Dis ; 10(12)2023 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-38132666

RESUMEN

Endovascular therapy (EVT) has revolutionized the management of acute ischaemic strokes with large vessel occlusion, with emerging evidence suggesting its benefit also in large infarct core volume strokes. In the last two years, four randomised controlled trials have been published on this topic-RESCUE-Japan LIMIT, ANGEL-ASPECT, SELECT2 and TENSION, with overall results showing that EVT improves functional and neurological outcomes compared to medical management alone. This review aims to summarise the recent evidence presented by these four trials and highlight some of the limitations in our current understanding of this topic.

3.
Clin Neurol Neurosurg ; 235: 108024, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37922680

RESUMEN

OBJECTIVE: To directly compare the 90-day outcomes of patients with symptomatic intracranial atherosclerotic disease (ICAD), extracranial carotid atherosclerotic disease (ECAD), and ICAD with concomitant ECAD. METHODS: From 2017-2021, patients who had (1) a transient ischemic attack or ischemic stroke within 30 days of admission as evaluated by a stroke neurologist and (2) ipsilateral ICAD and/or ECAD were prospectively enrolled. The cohort was divided into three groups: ICAD, ECAD, and ICAD with concomitant ECAD. The primary outcome assessed was 90-day ischemic stroke recurrence. Secondary outcomes included 90-day myocardial infarction (MI), all-cause mortality, and major adverse cardiovascular events (MACE, including cardiovascular death, nonfatal MI, and/or nonfatal ischemic stroke). RESULTS: Of 371 patients included in the analysis, 240 (64.7%) patients had ICAD only, 93 (25.0%) patients had ECAD only, and 38 (10.3%) patients had ICAD with concomitant ECAD. On multivariate time-to-event analysis adjusting for potential confounders and with ICAD as the reference comparator, the risk of 90-day clinical outcomes was highest among patients with ICAD and concomitant ECAD, with adjusted hazard ratios of 4.54 (95% CI=1.45, 14.2; p = 0.006), 9.32 (95% CI=1.58, 54.8; p = 0.014), and 8.52 (95% CI=3.54, 20.5; p < 0.001) for 90-day ischemic stroke, MI, and MACE, respectively. CONCLUSIONS: Patients with ICAD and concomitant ECAD have a poorer prognosis and are at significantly higher risk for 90-day ischemic stroke, MI, and MACE. Further research should focus on the evaluation of coronary atherosclerotic disease and more intensive medical therapy in this population.


Asunto(s)
Aterosclerosis , Enfermedades de las Arterias Carótidas , Arteriosclerosis Intracraneal , Ataque Isquémico Transitorio , Accidente Cerebrovascular Isquémico , Infarto del Miocardio , Accidente Cerebrovascular , Humanos , Estudios Prospectivos , Aterosclerosis/complicaciones , Accidente Cerebrovascular/complicaciones , Infarto del Miocardio/epidemiología , Enfermedades de las Arterias Carótidas/complicaciones , Enfermedades de las Arterias Carótidas/cirugía , Enfermedades de las Arterias Carótidas/epidemiología , Ataque Isquémico Transitorio/epidemiología , Ataque Isquémico Transitorio/complicaciones , Accidente Cerebrovascular Isquémico/complicaciones , Arteriosclerosis Intracraneal/epidemiología , Factores de Riesgo
4.
J Neurointerv Surg ; 15(10): 1039-1045, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36175014

RESUMEN

BACKGROUND: Mechanical thrombectomy (MT) is an effective treatment for patients with acute ischemic stroke (AIS) from basilar artery occlusion (BAO). OBJECTIVE: To compare the clinical outcomes of MT, with and without bridging intravenous thrombolysis (IVT), in acute BAO through a systematic review and meta-analysis of the current literature. METHODS: Systematic searches of Medline, EMBASE, and Cochrane Central were undertaken on August 1, 2022. Good functional outcome defined as 90-day modified Rankin Scale score 0-2 was the primary outcome measure. Secondary outcome measures were 90-day mortality, successful post-thrombectomy recanalization (modified Thrombolysis in Cerebral Infarction score ≥2b), symptomatic intracranial hemorrhage (sICH), and subarachnoid hemorrhage (SAH). RESULTS: Three studies reporting 1096 patients with BAO AIS were included in the meta-analysis. No significant differences in good functional outcome were detected between the two groups (RR=1.28 (95% CI 0.86 to 1.92); p=0.117). However, specifically patients with large artery atherosclerosis (LAA) benefited from bridging IVT (OR=2.52 (95% CI 1.51 to 4.22); p<0.001) with better functional outcomes. There was a significantly lower 90-day mortality rate for patients who underwent bridging IVT compared with MT alone (RR=0.70 (95% CI 0.62 to 0.80); p=0.008). No significant differences were detected in rates of post-treatment recanalization (RR=1.01 (95% CI 0.35 to 2.91); p=0.954), sICH (RR=0.96 (95% CI 0.66 to 1.42); p=0.724), and SAH (RR=0.93 (95% CI 0.31 to 2.83); p=0.563). CONCLUSIONS: In patients with AIS due to BAO, bridging IVT was associated with lower mortality rates at 90 days, compared with direct MT. There were no improved functional outcomes or increased sICH or SAH between both arms, However, patients with LAA benefited from bridging IVT, with better functional outcomes.


Asunto(s)
Isquemia Encefálica , Accidente Cerebrovascular Isquémico , Trombolisis Mecánica , Accidente Cerebrovascular , Hemorragia Subaracnoidea , Humanos , Accidente Cerebrovascular/tratamiento farmacológico , Accidente Cerebrovascular/etiología , Accidente Cerebrovascular/cirugía , Terapia Trombolítica , Accidente Cerebrovascular Isquémico/complicaciones , Isquemia Encefálica/tratamiento farmacológico , Isquemia Encefálica/cirugía , Arteria Basilar/diagnóstico por imagen , Tasa de Supervivencia , Trombectomía , Hemorragias Intracraneales/complicaciones , Resultado del Tratamiento , Hemorragia Subaracnoidea/complicaciones , Fibrinolíticos/uso terapéutico
5.
Clin Mol Hepatol ; 28(3): 483-496, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35232007

RESUMEN

BACKGROUND/AIMS: Non-alcoholic fatty liver disease (NAFLD) is associated with the development of cardiovascular disease. While existing studies have examined cardiac remodeling in NAFLD, there has been less emphasis on the development of carotid atherosclerosis and stroke. We sought to conduct a meta-analysis to quantify the prevalence, risk factors, and degree of risk increment of carotid atherosclerosis and stroke in NAFLD. METHODS: Embase and Medline were searched for articles relating to NAFLD, carotid atherosclerosis, and stroke. Proportional data was analysed using a generalized linear mixed model. Pairwise meta-analysis was conducted to obtain odds ratio or weighted mean difference for comparison between patients with and without NAFLD. RESULTS: From pooled analysis of 30 studies involving 7,951 patients with NAFLD, 35.02% (95% confidence interval [CI], 27.36-43.53%) had carotid atherosclerosis with an odds ratio of 3.20 (95% CI, 2.37-4.32; P<0.0001). Pooled analysis of 25,839 patients with NAFLD found the prevalence of stroke to be 5.04% (95% CI, 2.74-9.09%) with an odds ratio of 1.88 (95% CI, 1.23-2.88; P=0.02) compared to non-NAFLD. The degree of steatosis assessed by ultrasonography in NAFLD was closely associated with risk of carotid atherosclerosis and stroke. Older age significantly increased the risk of developing carotid atherosclerosis, but not stroke in NAFLD. CONCLUSION: This meta-analysis shows that a stepwise increment of steatosis of NAFLD can significantly increase the risk of carotid atherosclerosis and stroke development in NAFLD. Patients more than a third sufferred from carotid atherosclerosis and routine assessment of carotid atherosclerosis is quintessential in NAFLD.


Asunto(s)
Enfermedades Cardiovasculares , Enfermedades de las Arterias Carótidas , Accidente Cerebrovascular Isquémico , Enfermedad del Hígado Graso no Alcohólico , Enfermedades Cardiovasculares/complicaciones , Enfermedades de las Arterias Carótidas/complicaciones , Enfermedades de las Arterias Carótidas/diagnóstico , Enfermedades de las Arterias Carótidas/epidemiología , Humanos , Enfermedad del Hígado Graso no Alcohólico/complicaciones , Enfermedad del Hígado Graso no Alcohólico/diagnóstico , Enfermedad del Hígado Graso no Alcohólico/epidemiología , Factores de Riesgo
6.
Int Immunopharmacol ; 105: 108559, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35091337

RESUMEN

Cancer is caused by abnormal cell growth and metastasis to other tissues. Development of cancers is complex and underlining mechanisms are mostly unknown. Disco-interacting protein 2 homolog B (DIP2B) is a member of Dip2. There have been reports suggesting that Dip2B may participate in tumor growth and development. However, direct link between DIP2B and cancer development is missing. In this study, Dip2btm1a/+ heterozygous knockout mouse model was used to investigate tumor growth and metastasis. Results show that one allele knockout of Dip2B significantly promoted tumor growth and metastasis, decreased tumor cell apoptosis and reduced immune cell infiltration in tumors, most likely by altering immune system that includes reduction of macrophage and cytotoxic T-cells infiltration into tumor microenvironment.


Asunto(s)
Neoplasias , Proteínas del Tejido Nervioso , Microambiente Tumoral , Animales , Línea Celular Tumoral , Proliferación Celular/genética , Macrófagos , Ratones , Ratones Noqueados , Metástasis de la Neoplasia , Neoplasias/genética , Neoplasias/inmunología , Proteínas del Tejido Nervioso/genética , Microambiente Tumoral/genética
7.
J Neurointerv Surg ; 14(7): 683-687, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34353888

RESUMEN

BACKGROUND: Endovascular thrombectomy (EVT) in large vessel occlusion (LVO) in anterior circulation acute ischaemic stroke (AIS) results in good functional outcomes in only approximately 60% of the patients. Internal cerebral veins (ICVs) are easily visible, with a consistent midline location, and are linked to stroke outcomes. We hypothesize that ICV asymmetry on multiphasic CT angiogram (mCTA) can be an adjunctive predictor for poor functional outcomes. METHODS: We studied consecutive AIS patients from 2017 to 2019 with anterior circulation LVO treated with EVT regardless of intravenous thrombolysis. Asymmetrical ICV was defined as the presence of hypodensity (less opacification) on the ipsilateral occlusion side as compared with the contralateral side. The primary outcome was modified Rankin Score (mRS) score at 3 months. Secondary outcomes were good recanalization (modified Thrombolysis In Cerebral Infarction (mTICI) 2b-3), symptomatic hemorrhage, and mortality. RESULTS: A total of 185 patients were included with a median age of 70 years (IQR 59-77); 87 patients (47%) were female. 82 patients (44.3%) achieved good functional outcomes (mRS 0-2) at 3 months. On multivariate analysis, National Institutes of Health Stroke Scale (NIHSS) (OR 1.076, 95% CI 1.015 to 1.140; p<0.013), poor collateral score (OR 0.285, 95% CI 0.162 to 0.501; p<0.001), asymmetrical ICV on the peak venous phase (OR 2.47, 95% CI 1.115 to 5.471; p<0.026), and late venous phase of the mCTA (OR 2.642, 95% CI 1.161 to 6.016; p<0.021) were independent risks factors of poor outcomes. CONCLUSION: ICV asymmetry is a novel radiological sign which is independently associated with poor functional outcomes in EVT, even after correction for collateral circulation. Further studies are needed to validate this finding.


Asunto(s)
Isquemia Encefálica , Venas Cerebrales , Procedimientos Endovasculares , Accidente Cerebrovascular , Anciano , Isquemia Encefálica/etiología , Venas Cerebrales/diagnóstico por imagen , Venas Cerebrales/cirugía , Procedimientos Endovasculares/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Accidente Cerebrovascular/diagnóstico por imagen , Accidente Cerebrovascular/cirugía , Trombectomía/métodos , Resultado del Tratamiento
8.
Turk J Biol ; 45(5): 588-598, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34803456

RESUMEN

Bex2 is well known for its role in the nervous system, and is associated with neurological disorders, but its role in the lung's physiology is still not reported. To elucidate the functional role of Bex2 in the lung, we generated a Bex2 knock-out (KO) mouse model using the CRISPR-Cas9 technology and performed transcriptomic analysis. A total of 652 genes were identified as differentially expressed between Bex2 -/- and Bex2 +/+ mice, out of which 500 were downregulated, while 152 were upregulated genes. Among these DEGs, Ucp1, Myh6, Coxa7a1, Myl3, Ryr2, RNaset2b, Npy, Enob1, Krt5, Myl2, Hba-a2, and Nrob2 are the most prominent genes. Myl2, was the most downregulated gene, followed by Npy, Hba-a2, Rnaset2b, nr0b2, Klra8, and Ucp1. Tcte3, Eno1b, Zfp990, and Pcdha9 were the most upregulated DEGs. According to gene enrichment analysis, PPAR pathway, cardiac muscle contraction, and cytokine-cytokine receptor interaction were the most enriched pathways. Besides, the nuclear factor-κB signaling pathway and hematopoietic cell linage pathways were also enriched. Chronic obstructive pulmonary disease (COPD) is enriched among KEGG disease pathways. RT-qPCR assays confirmed the RNA-Seq results. This study opens a new window toward the biological functions of Bex2 in different systems.

9.
Electron. j. biotechnol ; Electron. j. biotechnol;52: 59-66, July. 2021. ilus, tab
Artículo en Inglés | LILACS | ID: biblio-1283592

RESUMEN

BACKGROUND: Many human genetic diseases arise from point mutations. These genetic diseases can theoretically be corrected through gene therapy. However, gene therapy in clinical application is still far from mature. Nearly half of the pathogenic single-nucleotide polymorphisms (SNPs) are caused by G:C>A:T or T:A>C:G base changes and the ideal approaches to correct these mutations are base editing. These CRISPR-Cas9-mediated base editing does not leave any footprint in genome and does not require donor DNA sequences for homologous recombination. These base editing methods have been successfully applied to cultured mammalian cells with high precision and efficiency, but BE4 has not been confirmed in mice. Animal models are important for dissecting pathogenic mechanism of human genetic diseases and testing of base correction efficacy in vivo. Cytidine base editor BE4 is a newly developed version of cytidine base editing system that converts cytidine (C) to uridine (U). RESULTS: In this study, BE4 system was tested in cells to inactivate GFP gene and in mice to introduce single-base substitution that would lead to a stop codon in tyrosinase gene. High percentage albino coat-colored mice were obtained from black coat-colored donor zygotes after pronuclei microinjection. Sequencing results showed that expected base changes were obtained with high precision and efficiency (56.25%). There are no off-targeting events identified in predicted potential off-target sites. CONCLUSIONS: Results confirm BE4 system can work in vivo with high precision and efficacy, and has great potentials in clinic to repair human genetic mutations.


Asunto(s)
Animales , Ratones , Adenosina Desaminasa , Citosina , Sistemas CRISPR-Cas , Edición Génica/métodos , Secuencia de Bases , Western Blotting , Modelos Animales , Reacción en Cadena en Tiempo Real de la Polimerasa , Mutación
10.
Transgenic Res ; 30(1): 35-50, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33394314

RESUMEN

Vascular endothelial growth factor (VEGF) is important for lung development and function but ideal mouse models are limited to decipher the quantitative relationship between VEGF expression levels and its proper development and pathogenesis. Human SPC promoter has been used to faithfully express genes or cDNAs in the pulmonary epithelium in many transgenic mouse models. In the study, a mouse model of lung-specific and reversible VEGF repression (hspc-rtTRtg/+/VegftetO/tetO) was generated. Human SPC promoter was used to drive lung-specific rtTR expression, a cDNA coding for doxycycline-regulated transcription repression protein. By crossing with VegftetO/tetO mice, that has tetracycline operator sequences insertion in 5'-UTR region, it allows us to reversibly inhibit lung VEGF transcription from its endogenous level through doxycycline food, water or injection. The tissue-specific inhibition of VEGF is used to mimic abnormal expression levels of VEGF in lung. Reduced VEGF expression in lung is confirmed by quantitative real time PCR and immunoblotting. Lung development and structure was analyzed by histology analysis and found significantly affected under low VEGF. The pulmonary epithelium and alveolarization are found abnormal with swelling alveolar septum and enlargement of air space. Genome-wide gene expression analysis identified that immune activities are involved in the VEGF-regulated lung functions. The transgenic mouse model can be used to mimic human pulmonary diseases. The mouse model confirms the important regulatory roles of epithelial expressed VEGF in lung development and function. This mouse model is valuable for studying VEGF-regulated lung development, pathogenesis and drug screening under low VEGF expression.


Asunto(s)
Enfermedades Pulmonares/genética , Pulmón/metabolismo , Organogénesis/genética , Proteína C Asociada a Surfactante Pulmonar/genética , Factor A de Crecimiento Endotelial Vascular/genética , Animales , Modelos Animales de Enfermedad , Células Epiteliales/metabolismo , Células Epiteliales/patología , Regulación del Desarrollo de la Expresión Génica/genética , Humanos , Pulmón/crecimiento & desarrollo , Pulmón/patología , Enfermedades Pulmonares/patología , Ratones , Ratones Transgénicos , Regiones Promotoras Genéticas/genética
11.
Comput Struct Biotechnol J ; 18: 2381-2390, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33005301

RESUMEN

Disco-interacting protein 2 homolog B (Dip2B) is a member of Dip2 family encoded by Dip2b gene. Dip2B has been reported to regulate murine epithelial KIT+ progenitor cell expansion and differentiation epigenetically via exosomal miRNA targeting during salivary gland organogenesis. However, its molecular functions, cellular activities and biological process remain unstudied. Here, we investigated the transcriptome of Dip2B-deficient mouse embryonic lung fibroblasts (MELFs) isolated from E14.5 embryos by RNA-Seq. Expression profiling identified 1369 and 1104 differentially expressed genes (DEGs) from Dip2b-/- and Dip2b+/- MELFs in comparisons to wild-type (Dip2b+/+ ). Functional clustering of DEGs revealed that many gene ontology terms belong to membrane activities such as 'integral component of plasma membrane', and 'ion channel activity', suggesting possible roles of Dip2B in membrane integrity and membrane function. KEGG pathway analysis revealed that multiple metabolic pathways are affected in Dip2b- / - and Dip2b +/ - when compared to Dip2b +/+ MELFs. These include 'protein digestion and absorption', 'pancreatic secretion' and 'steroid hormone synthesis pathway'. These results suggest that Dip2B may play important roles in metabolism. Molecular function analysis shows transcription factors including Hox-genes, bHLH-genes, and Forkhead-genes are significantly down-regulated in Dip2b- / - MELFs. These genes are critical in embryo development and cell differentiation. In addition, Dip2B-deficient MELFs demonstrated a reduction in cell proliferation and migration, and an increase in apoptosis. All results indicate that Dip2B plays multiple roles in cell proliferation, migration and apoptosis during embryogenesis and may participate in control of metabolism. This study provides valuable information for further understanding of the function and regulatory mechanisms of Dip2B.

12.
Gene ; 758: 144975, 2020 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-32707302

RESUMEN

Dip2C is highly expressed in brain and many other tissues but its biological functions are still not clear. Genes regulated by Dip2C in brain have never been studied. The clustered regularly interspaced short palindromic repeat (CRISPR)/CRISPR-associated protein (Cas) systems, adaptive immune systems of bacteria and archaea, have been recently developed and broadly used in genome editing. Here, we describe targeted gene deletions of Dip2c gene in mice via CRISPR/Cas9 system and study of brain transcriptome under Dip2C regulation. The CRISPR/Cas9 system effectively generated targeted deletions of Dip2c by pronuclei injection of plasmids that express Cas9 protein and two sgRNAs. We achieved targeted large fragment deletion with efficiencies at 14.3% (1/7), 66.7% (2/3) and 20% (1/5) respectively in 3 independent experiments, averaging 26.7%. The large deletion DNA segments are 160.4 kb (Dip2CΔ160kb), spanning from end of exon 4 to mid of exon 38. A mouse with two base pair deletion was generated from a single sgRNA targeting in exon 4 (Dip2cΔ2bp) by non-homologous end joining (NHEJ). Loss of gene expression for Dip2c mRNA was confirmed by quantitative real-time PCR (qPCR). Dip2C-regulated genes and pathways in brain were investigated through RNAseq of Dip2cΔ2bp. In total, 838 genes were found differentially regulated, with 252 up and 586 down. Gene ontology (GO) analysis indicated that DEGs in brain are enriched in neurological functions including 'memory', 'neuropeptide signaling pathway', and 'response to amphetamine' while KEGG analysis shows that 'neuroactive ligand-receptor interaction pathway' is the most significantly enriched. DEGs Grid2ip, Grin2a, Grin2c, Grm4, Gabbr2, Gabra5, Gabre, Gabrq, Gabra6 and Gabrr2 are among the highly regulated genes by Dip2C. Results confirm Dip2C may play important roles in brain development and function.


Asunto(s)
Encéfalo/metabolismo , Regulación de la Expresión Génica/genética , Péptidos y Proteínas de Señalización Intracelular/genética , Proteínas de Neoplasias/genética , Transcriptoma/genética , Animales , Encéfalo/citología , Encéfalo/crecimiento & desarrollo , Sistemas CRISPR-Cas , Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas/genética , Femenino , Eliminación de Gen , Edición Génica/métodos , Técnicas de Inactivación de Genes , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos DBA , Ratones Noqueados , ARN Guía de Kinetoplastida/genética
13.
Sci Rep ; 10(1): 7307, 2020 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-32350391

RESUMEN

Flexible, light-weight and robust thermoelectric (TE) materials have attracted much attention to convert waste heat from low-grade heat sources, such as human body, to electricity. Carbon nanotube (CNT) yarn is one of the potential TE materials owing to its narrow band-gap energy, high charge carrier mobility, and excellent mechanical property, which is conducive for flexible and wearable devices. Herein, we propose a way to improve the power factor of CNT yarns fabricated from few-walled carbon nanotubes (FWCNTs) by two-step method; Joule-annealing in the vacuum followed by doping with p-type dopants, 2,3,5,6-tetrafluo-7,7,8,8-tetracyanoquinodimethane (F4TCNQ). Numerical calculations and experimental results explain that Joule-annealing and doping modulate the electronic states (Fermi energy level) of FWCNTs, resulting in extremely large thermoelectric power factor of 2250 µW m-1 K-2 at a measurement temperature of 423 K. Joule-annealing removes amorphous carbon on the surface of the CNT yarn, which facilitates doping in the subsequent step, and leads to higher Seebeck coefficient due to the transformation from (semi) metallic to semiconductor behavior. Doping also significantly increases the electrical conductivity due to the effective charge transfers between CNT yarn and F4TCNQ upon the removal of amorphous carbon after Joule-annealing.

15.
PLoS One ; 14(7): e0213702, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31291246

RESUMEN

Disconnected interacting protein 2 homolog A (DIP2A) is highly expressed in nervous system and respiratory system of developing embryos. However, genes regulated by Dip2a in developing brain and lung have not been systematically studied. Transcriptome of brain and lung in embryonic 19.5 day (E19.5) were compared between wild type and Dip2a-/- mice. An average of 50 million reads per sample was mapped to the reference sequence. A total of 214 DEGs were detected in brain (82 up and 132 down) and 1900 DEGs in lung (1259 up and 641 down). GO enrichment analysis indicated that DEGs in both Brain and Lung were mainly enriched in biological processes 'DNA-templated transcription and Transcription from RNA polymerase II promoter', 'multicellular organism development', 'cell differentiation' and 'apoptotic process'. In addition, COG classification showed that both were mostly involved in 'Replication, Recombination, and Repair', 'Signal transduction and mechanism', 'Translation, Ribosomal structure and Biogenesis' and 'Transcription'. KEGG enrichment analysis showed that brain was mainly enriched in 'Thyroid cancer' pathway whereas lung in 'Complement and Coagulation Cascades' pathway. Transcription factor (TF) annotation analysis identified Zinc finger domain containing (ZF) proteins were mostly regulated in lung and brain. Interestingly, study identified genes Skor2, Gpr3711, Runx1, Erbb3, Frmd7, Fut10, Sox11, Hapln1, Tfap2c and Plxnb3 from brain that play important roles in neuronal cell maturation, differentiation, and survival; genes Hoxa5, Eya1, Errfi1, Sox11, Shh, Igf1, Ccbe1, Crh, Fgf9, Lama5, Pdgfra, Ptn, Rbp4 and Wnt7a from lung are important in lung development. Expression levels of the candidate genes were validated by qRT-PCR. Genome wide transcriptional analysis using wild type and Dip2a knockout mice in brain and lung at embryonic day 19.5 (E19.5) provided a genetic basis of molecular function of these genes.


Asunto(s)
Encéfalo/metabolismo , Pulmón/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Animales , Encéfalo/embriología , Diferenciación Celular/genética , Supervivencia Celular/genética , Perfilación de la Expresión Génica , Regulación del Desarrollo de la Expresión Génica , Pulmón/embriología , Ratones , Ratones Noqueados , Anotación de Secuencia Molecular , Neuronas/citología , Neuronas/metabolismo , Proteínas Nucleares/deficiencia , Análisis de Secuencia de ARN , Factores de Transcripción/genética
16.
Am J Physiol Endocrinol Metab ; 316(2): E145-E155, 2019 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-30398903

RESUMEN

Obesity is the result of excessive energy accumulation and is associated with many diseases. We previously reported that universal repression of vascular endothelial growth factor (VEGF) leads to brown-like adipocyte development in white adipose tissues, and that these mice are resistant to obesity (Lu X et al. Endocrinology 153: 3123-3132, 2012). Using an adipose-specific VEGF repression mouse model (aP2-rtTR-krabtg/+/VEGFtetO/tetO), we show that adipose-specific VEGF repression can repeat the previous phenotypes, including adipose browning, increased energy consumption, and reduction in body weight. Expression of brown adipose-associated genes is increased, and white adipose-associated genes are downregulated under VEGF repression. Our study demonstrates that adipose-specific VEGF repression can lead to antiobesity activity through adipose browning and has potential clinical value.


Asunto(s)
Tejido Adiposo Pardo/metabolismo , Tejido Adiposo Blanco/metabolismo , Obesidad/genética , Factor A de Crecimiento Endotelial Vascular/genética , Tejido Adiposo/metabolismo , Animales , Metabolismo Energético/genética , Ratones , Mutación , Obesidad/metabolismo , Pérdida de Peso/genética
17.
RSC Adv ; 8(64): 36563-36570, 2018 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-35558964

RESUMEN

As a thermoelectric (TE) material suited to applications for recycling waste-heat into electricity through the Seebeck effect, poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonic acid) (PEDOT:PSS) is of great interest. Our research demonstrates a comprehensive study of different post-treatment methods with nitric acid (HNO3) to enhance the thermoelectric properties of PEDOT:PSS. The optimum conditions are obtained when PEDOT:PSS is treated with HNO3 for 10 min at room temperature followed by passing nitrogen gas (N2) with a pressure of 0.2 MPa. Upon this treatment, PEDOT:PSS changes from semiconductor-like behaviour to metal-like behaviour, with a simultaneous enhancement in the electrical conductivity and Seebeck coefficient at elevated temperature, resulting in an increase in the thermoelectric power factor from 0.0818 to 94.3 µW m-1 K-2 at 150 °C. The improvement in the TE properties is ascribed to the combined effects of phase segregation and conformational change of the PEDOT due to the weakened coulombic attraction between PEDOT and PSS chains by nitric acid as well as the pressure of the N2 gas as a mechanical means.

18.
Acute Med ; 13(3): 132-8, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25229065

RESUMEN

A wide variety of conditions can present as acute polyarthritis, ranging from those that are potentially life threatening, to those that are self-limiting, and those that represent the early stages of a persistent and potentially destructive form of arthritis. In this article, we describe the diagnostic approach and initial management of patients with recent onset polyarthritis, with the aid of an illustrative case vignette.


Asunto(s)
Artritis/diagnóstico , Diagnóstico Precoz , Enfermedad Aguda , Diagnóstico Diferencial , Manejo de la Enfermedad , Humanos
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