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1.
BMC Genomics ; 24(1): 458, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37582696

RESUMO

BACKGROUND: Hull colour is an important morphological marker for selection in seed production of foxtail millet. However, the molecular mechanisms underlying hull colour variation remain unknown. RESULTS: An F7 recombinant inbred line (RIL) population containing 215 lines derived from Hongjiugu × Yugu18 was used to analyze inheritance and detect the quantitative trait loci (QTL) for four hull colour traits using major gene plus polygene mixed inheritance analysis and composite interval mapping (CIM) in four environments. Genetic analysis revealed that the hull colour L* value (HCL*) was controlled by two major genes plus additive polygenes, the hull colour a* value (HCa*) was controlled by three major genes, the hull colour b* value (HCb*) was controlled by two major genes plus polygenes, and the hull colour C* value (HCC*) was controlled by four major genes. A high-density genetic linkage map covering 1227.383 cM of the foxtail millet genome, with an average interval of 0.879 cM between adjacent bin markers, was constructed using 1420 bin markers. Based on the genetic linkage map and the phenotypic data, a total of 39 QTL were detected for these four hull colour traits across four environments, each explaining 1.50%-49.20% of the phenotypic variation. Of these, six environmentally stable major QTL were co-localized to regions on chromosomes 1 and 9, playing a major role in hull colour. There were 556 annotated genes within the two QTL regions. Based on the functions of homologous genes in Arabidopsis and the Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) gene annotations, five genes were predicted as candidate genes for further studies. CONCLUSIONS: This is the first study to use an inheritance model and QTL mapping to determine the genetic mechanisms of hull colour trait in foxtail millet. We identified six major environmentally stable QTL and predicted five potential candidate genes to be associated with hull colour. These results advance the current understanding of the genetic mechanisms underlying hull colour traits in foxtail millet and provide additional resources for application in genomics-assisted breeding and potential isolation and functional characterization of the candidate genes.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Setaria (Planta) , Locos de Características Quantitativas , Mapeamento Cromossômico/métodos , Setaria (Planta)/genética , Carcinoma Hepatocelular/genética , Cor , Neoplasias Hepáticas/genética , Melhoramento Vegetal , Estudos de Associação Genética
2.
Reprod Biol Endocrinol ; 21(1): 17, 2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36737817

RESUMO

BACKGROUND: Low vitamin D status has been associated with an increased risk for infertility. Recent evidence regarding the efficacy of vitamin D supplementation in improving reproductive outcomes is inconsistent. Therefore, this systematic review was conducted to investigate whether vitamin D supplementation could improve the reproductive outcomes of infertile patients and evaluate how the parameters of vitamin D supplementation affected the clinical pregnancy rate. METHODS: We searched seven electronic databases (CNKI, Cqvip, Wanfang, PubMed, Medline, Embase, and Cochrane Library) up to March 2022. Randomized and cohort studies were collected to assess the reproductive outcomes difference between the intervention (vitamin D) vs. the control (placebo or none). Mantel-Haenszel random effects models were used. Effects were reported as odds ratio (OR) and their 95% confidence interval (CI). PROSPERO database registration number: CRD42022304018. RESULTS: Twelve eligible studies (n = 2352) were included: 9 randomized controlled trials (RCTs, n = 1677) and 3 cohort studies (n = 675). Pooled results indicated that infertile women treated with vitamin D had a significantly increased clinical pregnancy rate compared with the control group (OR: 1.70, 95% CI: 1.24-2.34; I2 = 63%, P = 0.001). However, the implantation, biochemical pregnancy, miscarriage, and multiple pregnancy rates had no significant difference (OR: 1.86, 95% CI: 1.00-3.47; I2 = 85%, P = 0.05; OR: 1.49; 0.98-2.26; I2 = 63%, P = 0.06; OR: 0.98, 95% CI: 0.63-1.53; I2 = 0%, P = 0.94 and OR: 3.64, 95% CI: 0.58-11.98; I2 = 68%, P = 0.21). The improvement of clinical pregnancy rate in the intervention group was influenced by the vitamin D level of patients, drug type, the total vitamin D dosage, the duration, administration frequency, and daily dosage of vitamin D supplementation. The infertile women (vitamin D level < 30 ng/mL) treated with the multicomponent drugs including vitamin D (10,000-50,000 IU or 50,000-500,000 IU), or got vitamin D 1000-10,000 IU daily, lasting for 30-60 days could achieve better pregnancy outcome. CONCLUSION: To the best of our knowledge, this is the first meta-analysis systematically investigated that moderate daily dosing of vitamin D supplementation could improve the clinical pregnancy rate of infertile women and reported the effects of vitamin D supplementation parameters on pregnancy outcomes. A larger sample size and high-quality RCTs are necessary to optimize the parameters of vitamin D supplementation to help more infertile patients benefit from this therapy.


Assuntos
Infertilidade Feminina , Feminino , Humanos , Gravidez , Infertilidade Feminina/tratamento farmacológico , Infertilidade Feminina/induzido quimicamente , Vitaminas/uso terapêutico , Vitamina D/uso terapêutico , Taxa de Gravidez , Suplementos Nutricionais
3.
Sensors (Basel) ; 23(21)2023 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-37960461

RESUMO

Accurate perception, especially situational awareness, is central to the evolution of autonomous driving. This necessitates understanding both the traffic conditions and driving intentions of surrounding vehicles. Given the unobservable nature of driving intentions, the hidden Markov model (HMM) has emerged as a popular tool for intention recognition, owing to its ability to relate observable and hidden variables. However, HMM does not account for the inconsistencies present in time series data, which are crucial for intention recognition. Specifically, HMM overlooks the fact that recent observations offer more reliable insights into a vehicle's driving intention. To address the aforementioned limitations, we introduce a time-sequenced weights hidden Markov model (TSWHMM). This model amplifies the significance of recent observations in recognition by integrating a discount factor during the observation sequence probability computation, making it more aligned with practical requirements. Regarding the model's input, in addition to easily accessible states of a target vehicle, such as lateral speed and heading angle, we also introduced lane hazard factors that reflect collision risks to capture the traffic environment information surrounding the vehicle. Experiments on the HighD dataset show that TSWHMM achieves recognition accuracies of 94.9% and 93.4% for left and right lane changes, surpassing both HMM and recurrent neural networks (RNN). Moreover, TSWHMM recognizes lane-changing intentions earlier than its counterparts. In tests involving more complex roundabout scenarios, TSWHMM achieves an accuracy of 87.3% and can recognize vehicles' intentions to exit the roundabout 2.09 s in advance.

4.
Macromol Rapid Commun ; 43(20): e2200403, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35926148

RESUMO

The morphology transition from primary to hierarchical adsorption-type microporous domains of amphiphilic block copolymer (BCP) honeycomb-structured films is demonstrated by a facile swollen based breath figure (BF) method. The characteristic parameters of poly(4-vinylpyridine)-block-polystyrene (P4VP-b-PS) hierarchical micro- and submicroporous films can be controlled by changing the length of segments or subsequent swelling conditions. A plausible mechanism is demonstrated in this research. A typical amphiphilic BCP with very low volume content of hydrophilic blocks (fP4VP ≤ 0.050) can efficiently stabilize water droplets and inherently assist in the formation of morphology transition. This BCP film can be used for Cr(VI) removal from wastewater, which additionally has enormous potential application in the field of novel optical devices, soft lithography, size-selective separation, etc.

5.
Clin Exp Hypertens ; 44(7): 619-626, 2022 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-35838365

RESUMO

BACKGROUND: To explore the relationship between duration of hypertension and inflammatory cell levels and to assess whether long duration might aggravate these inflammatory cells among Chinese urban community residents. METHODS: A cross-sectional study of 5199 hypertensive and 2675 no-hypertensive participants who registered in community health service centers for physical examination was performed in Tianjin, China. Data of blood pressure and inflammatory cells were collected. Binary logistic regression was performed to assess the effect of hypertensive duration on the level of inflammatory cells before and after adjustment for the potential confounding factors. RESULTS: Individuals with hypertension had significantly higher level of leukocyte count, neutrophil proportion, neutrophil-to-lymphocyte ratio (NLR), and lower level of lymphocyte proportion than those without hypertension. Two-way ANOVA showed that hypertension duration, rather than blood pressure control or their interaction, had significant influence on the levels of neutrophil proportion, lymphocyte proportion, and NLR. With the prolongation of the duration of hypertension, the level of neutrophil proportion and NLR increased, and the level of lymphocyte proportion decreased. Long hypertension duration (>10 years) was significantly associated with high level of neutrophil proportion (OR = 1.48, 95% CI: 1.25, 1.75), high level of NLR (OR = 1.53, 95% CI: 1.29, 1.81), and low level of lymphocyte proportion (OR = 1.54, 95% CI: 1.30, 1.82) in comparison with short duration (<5 years) after adjustment for confounding factors. CONCLUSION: Hypertensive patients had higher level of leukocyte count, neutrophil proportion, NLR, and lower level of lymphocyte proportion than normotensive ones. Long duration of hypertension was associated with aggravated inflammatory biomarkers.


Assuntos
Hipertensão , China , Estudos Transversais , Humanos , Contagem de Leucócitos , Linfócitos , Neutrófilos
6.
Eur Radiol ; 31(11): 8335-8341, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33890150

RESUMO

OBJECTIVES: To investigate the use of reverse attenuation gradient sign (RAGS) in CT angiography (CTA) to differentiate total from subtotal occlusion in lower extremities which poses different challenges for the procedure and carries different prognoses. METHODS: Eighty patients with 91 lesions in the lower extremities were divided into total occlusion (TO) group and subtotal occlusion (SO) group confirmed by digital subtraction angiography. The CT numbers of vascular lumen at the end of lesion (proximal, P) and at the first entrance (distal, D) of the lateral branch were measured and their difference (CT(PD) = CT(P) - CT(D)) of each lesion was calculated. The CT number gradient (G(DP) = 2 * CT(PD)/[CT(P) + CT(D)]) was calculated by dividing the CT number difference by the average CT number of the two points. The existence of RAGS where the CT number at the distal point is higher than that at the proximal point (CT(PD) and G(PD) < 0) was determined and the diagnostic efficacy of using RAGS in CTA for differentiating total from subtotal occlusive lesions in lower extremities was calculated. RESULTS: The SO group had higher CT numbers than the TO group (p < 0.001). More importantly, the SO group had positive CT number gradient (G(PD) > 0), while the gradient was negative (G(PD) < 0) in the TO group. The specificity and sensitivity of using RAGS (G(PD) < 0) in images for diagnosing TO of lower extremity were 97.6% and 92.0%, respectively, and 87.8% and 88.0% using the standard CTA images. CONCLUSION: The use of RAGS in CTA images has high diagnostic accuracy to differentiate TO from SO in lower extremities. KEY POINTS: • Total occlusions often exhibit higher CT number at distal point than at proximal point to the occlusion. • The reverse attenuation gradient sign (RAGS) may be determined using the CT number measurements between the proximal and distal points after occlusion. • RAGS can be used to improve the diagnostic efficiency in CTA to differentiate between total and subtotal occlusions of lower extremity arteries.


Assuntos
Arteriopatias Oclusivas , Angiografia por Tomografia Computadorizada , Angiografia Digital , Arteriopatias Oclusivas/diagnóstico por imagem , Vasos Coronários/diagnóstico por imagem , Humanos , Extremidade Inferior/diagnóstico por imagem , Sensibilidade e Especificidade
7.
J Infect Chemother ; 27(10): 1520-1524, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34215497

RESUMO

BACKGROUND: Central nervous system (CNS) infection due to Exophiala dermatitidis is rare and fatal, and primarily reported in immunocompromised patients or those with caspase recruitment domain-containing protein 9 deficiency. Herein, we describe a case of an otherwise healthy person (without underlying disease or gene deficiency) diagnosed with Exophiala dermatitidis meningoencephalitis. The patient achieved clinical remission under high-dose antifungal therapy in the first 14 months but died after 2 years of the therapy. CASE PRESENTATION: A 15-year-old student with headache and fever was admitted to our department. Lumbar puncture showed increased cerebrospinal fluid (CSF) pressure, moderately high CSF protein levels and cell counts, and a remarkable decrease in CSF glucose and chloride. Magnetic resonance imaging of the brain revealed multiple lesions and cerebral pia mater enhancement. CSF culture confirmed E. dermatitidis infection. We administered 4-week antifungal therapy of amphotericin B, but his CSF culture remained positive. After receiving the 12-week standard dose of voriconazole (200 mg q12h), the patient's CSF culture became negative, but his condition deteriorated with intracranial lesion enlargement. We administered a high-dose voriconazole therapy (600-800 mg per day) for 12 months, which led to clinical remission. The voriconazole dose was reduced due to adverse effects including hepatic dysfunction and hypokalemia, and the disease progressed with high intracranial pressure and epileptic seizures. CONCLUSIONS: CNS infection caused by E. dermatitidis is fatal and the most serious form of fungal infection. Initially, high-dose and long-term antifungal therapy could be effective. Gene defect and related antifungal immunodeficiency may be the most important pathogenic and lethal factor.


Assuntos
Exophiala , Meningoencefalite , Adolescente , Antifúngicos/uso terapêutico , Humanos , Meningoencefalite/tratamento farmacológico , Voriconazol/uso terapêutico
8.
J Obstet Gynaecol Res ; 47(6): 2157-2165, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33765692

RESUMO

AIM: To clarify the association of serum kisspeptin levels in women with polycystic ovary syndrome (PCOS) by meta-analysis. METHODS: Two English databases and two Chinese databases were searched for the relationship between kisspeptin and PCOS published from 2009. After the studies screening according to specific principles, we used STATA 12.0 for meta-analysis. Standardized mean difference (SMD) and its 95% confidence intervals (95% CIs) were used as the effect size and STATA 12.0 software was performed by this meta-analysis. RESULTS: Nine articles were included in the end, with a total of 1282 participants (699 patients and 583 controls). Heterogeneity between studies was statistically significant. Therefore, the random effects model was used to combine the effects. Meta-analysis showed statistically significant differences in serum kisspeptin levels between the PCOS patients and controls (SMD = 0.57, 95% CI [0.32, 0.82]), which indicated that there is a strong association between serum kisspeptin levels and PCOS. The source of high heterogeneity between the inclusion studies (I2  = 73.2%) might be due to the small sample size. The larger variation of kisspeptin concentration might be caused by different diagnosis criteria of PCOS and short half-time period of kisspeptin combined with nonstandard testing process. CONCLUSION: Serum kisspeptin levels in PCOS patients were higher than non-PCOS patients. It is a hint to indicate us that kisspeptin might be an independent biomarker of PCOS patients.


Assuntos
Kisspeptinas , Síndrome do Ovário Policístico , Biomarcadores , Feminino , Humanos
9.
J Cell Physiol ; 234(11): 19728-19739, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-30941772

RESUMO

Stress conditions like hypoxia, ischemia, and ischemia/reperfusion can trigger excessive endoplasmic reticulum stress (ERS), which can lead to cell apoptosis-induced skeletal muscle atrophy in non-hibernators. However, although hibernators experience multiple stress conditions during hibernation, their skeletal muscles appear to be well protected. We hypothesize that hibernators effectively avoid cell apoptosis, at least partially, by controlling ERS level. Here, we focused on the potential occurrence of ERS and how hibernators cope with it during different hibernation states. Results indicated that the protein expression levels of glucose-regulated protein 78 (GRP78), phosphorylated PKR-like ER protein kinase, phosphorylated eukaryotic translation initiation factor 2α (p-eIF2α), and activating transcription factor 4 were significantly increased during hibernation, but primarily recovered in posthibernation. In the torpor-arousal cycle, the expression levels of the above indicators were lower during inter-bout arousal (IBA) than that during late torpor (LT). However, there was no change in C/EBP homologous protein expression and no apoptosis in skeletal muscles during the different hibernation states. In conclusion, the upregulation of p-eIF2α and GRP78 were identified as two crucial mechanisms mediated by the PERK signaling pathway to alleviate elevated ERS. The downregulation of ERS during IBA may be a unique countermeasure for hibernating squirrels to prevent excessive ERS. Thus, these special anti-excessive ERS abilities of ground squirrels contribute to the prevention of skeletal muscle cell apoptosis during hibernation.


Assuntos
Hibernação/genética , Atrofia Muscular/genética , Sciuridae/fisiologia , eIF-2 Quinase/genética , Animais , Apoptose/genética , Chaperona BiP do Retículo Endoplasmático , Estresse do Retículo Endoplasmático/genética , Fator de Iniciação 2 em Eucariotos/genética , Regulação da Expressão Gênica/genética , Proteínas de Choque Térmico/genética , Hibernação/fisiologia , Humanos , Músculo Esquelético/metabolismo , Músculo Esquelético/fisiopatologia , Atrofia Muscular/fisiopatologia , Sciuridae/genética , Transdução de Sinais/genética , Fator de Transcrição CHOP
10.
Small ; 15(16): e1900110, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30913373

RESUMO

Crosslinked liquid crystalline polymers (CLCPs) have garnered extensive attention in recent years for their significant values in the design of light-driven soft actuators. However, poor processabilities due to the insoluble and infusible crosslinked networks prevent their practical applications severely. In this study, a weldable azobenzene-containing CLCP is designed with photo- and humidity-responsive actuations, which enables a cut-and-weld process to 3D CLCP architectures. The tensile properties and stability are almost unchanged after welding, much better than those of the films pasted by common adhesive tapes. Meanwhile, the mechanisms of the welding process are clarified on the base of surface hydrogen bonding and further crosslinking. By taking advantage of the cut-and-weld process, a 3D "claw" integrated into a robotic arm is realized for grabbing millimeter-scale objects by remote control. This work enhances significantly not only the processability of CLCP films but also the utilization of leftover pieces, which provides an efficient approach to create functional 3D structures from film precursors for the potential application in the smart materials.

11.
BMC Cancer ; 18(1): 27, 2018 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-29301498

RESUMO

BACKGROUND: Lin28B and its paralog Lin28A are small RNA binding proteins that have similar inhibitory effects, although they target separate steps in the maturation of let-7 miRNAs in mammalian cells. Because Lin28B participates in the promotion and development of tumors mostly by blocking the let-7 tumor suppressor family members, we sought to explore the associated mechanisms to gain insights into how Lin28B might be decreased in human cancer cells to increase let-7 levels and reverse malignancy. RESULTS: We demonstrated that the histone acetyltransferase PCAF, via its cold shock domain, directly interacts with and subsequently acetylates Lin28B in lung adenocarcinoma-derived H1299 cells. RT-qPCR assays showed that both let-7a-1 and let-7g were increased in PCAF-transfected H1299 cells. Lin28B is acetylated by ectopic PCAF and translocates from the nucleus to the cytoplasm in H1299 cells. CONCLUSIONS: The effects of acetylated Lin28B on let-7a-1 and let-7g are similar to that of stable knockdown of Lin28B in H1299 cells. The new role of PCAF in mediating Lin28B acetylation and the specific release of its target microRNAs in H1299 cells may shed light on the potential application of let-7 in the clinical treatment of lung cancer patients.


Assuntos
Adenocarcinoma/genética , Neoplasias Pulmonares/genética , MicroRNAs/genética , Proteínas de Ligação a RNA/genética , Fatores de Transcrição de p300-CBP/genética , Acetilação , Adenocarcinoma/patologia , Adenocarcinoma de Pulmão , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Pulmonares/patologia , Ligação Proteica
12.
Soft Matter ; 14(35): 7107-7112, 2018 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-30175354

RESUMO

Block copolymer (BCP) films with perpendicularly aligned cylindrical domains of high aspect ratio have important applications in diverse fields. However, an aspect ratio of the cylinders as high as 200 has rarely been reported so far. Here we demonstrate an efficient route to the formation of normally aligned P4VP cylinders with high aspect ratio surrounded by a matrix of azobenzene-containing block (PMA(Az)) via hierarchical self-assembly. A crisscross structure, consisting of parallelly aligned liquid crystalline (LC) layers and normally aligned self-assembly domains, is expected to assist the formation of well-defined nanostructures. The LC layers in the cylindrical films self-assemble to form smectic phase after solvent annealing, as confirmed by WAXD and UV-vis spectra. We found that the aspect ratio of the vertical P4VP cylinders is up to 200 and the film thickness reaches 6 µm. P4VP is a functional polymer, making this P4VP-b-PMA(Az) film more suitable for advanced filters, multi-nanochannels, nanolithography, and high-density storage media, etc.

13.
J Asian Nat Prod Res ; 20(11): 1064-1074, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29852780

RESUMO

A series of novel tetrandrine (Tet) derivatives were synthesized through Suzuki -Miyaura reaction and evaluated for their cytotoxicity against human non-small cell lung carcinoma (NSCLC) A549 cells. Interestingly, most of derivatives showed similar cytotoxicity to Tet against NSCLC A549 cells, and particularly, compounds Y5, Y6, Y9 and Y11 showed the most significant cytotoxic effects with IC50 values ranging from 3.87 to 4.66 mM. The present study is expected to contribute to the future design of more effective anticancer agents in lung cancer chemotherapy.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Benzilisoquinolinas/química , Benzilisoquinolinas/farmacologia , Células A549 , Antineoplásicos Fitogênicos/síntese química , Antineoplásicos Fitogênicos/química , Carcinoma Pulmonar de Células não Pequenas , Sobrevivência Celular/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular
14.
Opt Lett ; 42(13): 2619-2622, 2017 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-28957299

RESUMO

Copper(II) chalcogenide nanocrystals, including Cu2-xY (Y=S, Se, and Te), have an intense localized surface plasmon resonance (LSPR) band in the near-infrared (NIR) region. In this research, colloidal Cu2-xSe@Cu2-xS nanorods were synthesized using the organometallic colloidal and cation-exchange methods. The dynamics of LSPR were investigated using ultrafast laser pulses via pump-probe experiments in the NIR region. Investigation of the transient absorption spectra revealed an LSPR spectral band from approximately 850 to 1350 nm, with a center wavelength of 1030 nm. The kinetics of the recovering plasmon maximum, probed at the peak wavelength of 1030 nm, exhibited a strong nonlinear response for plasmonic absorption, with a modulation depth exceeding 25% in the transmitted signal under a pump fluence of 3.97 mJ/cm2. The ultrafast nonlinear optical properties of these plasmonic nanoparticles could be used as excellent saturable absorbers (SAs) in ultrafast lasers. A compact passively Q-switched Yb3+:YAG microchip laser with a Cu2-xSe@Cu2-xS SA was investigated. Furthermore, a maximum average output power of 187 mW was obtained, with a pulse energy of 4.11 µJ, pulse duration of 8.5 µs, and repetition rate of 45.45 KHz at a pump power of 8.7 W.

16.
Macromol Rapid Commun ; 38(5)2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28117519

RESUMO

Nanoporous thin films with pore size of sub-10 nm are fabricated using an acid-cleavable block copolymer (BCP), a benzoic imine junction between poly(ethylene oxide) (PEO) and poly(methacrylate) (PMAAz) bearing an azobenzene side chain (denoted as PEO-bei-PMAAz) as the precursor. After a thermal annealing, the block copolymers are self-assembled to form highly ordered PEO cylinders within a PMAAz matrix normal to the film, even in the case of low BCP molecular weight due to the existing of the liquid crystalline (LC) azobenzene rigid segment. Thus, PMAAz thin films with pore size of ≈7 nm and density of ≈1012 cm-2 are obtained after removal of the PEO minor phase by breaking the benzoic imine junction under mild acidic conditions. This work enriches the nanoporous polymer films from BCP precursors and introduces the LC property as a functionality which can further enhance the mechanical properties of the films and broaden their applications.


Assuntos
Ácidos/química , Nanopartículas/química , Polietilenoglicóis/química , Ácidos Polimetacrílicos/química , Estrutura Molecular , Tamanho da Partícula , Porosidade , Propriedades de Superfície
17.
Zhongguo Zhong Yao Za Zhi ; 42(5): 863-869, 2017 Mar.
Artigo em Zh | MEDLINE | ID: mdl-28994527

RESUMO

Toad venom (Chansu) is prepared from the dried secretion of Bufo bufo gargarizans or B. melanostictus. It is not only one of the famous and expensive traditional Chinese medicines(TCMs) from animal origin, but also one of 28 kinds of toxic TCMs to be required for special management issued by the State Council of the People's Republic of China. Chansu contains the rich bufadienolides and indole alkaloids, and displays various bioactivity including cardiotonic, anti-tumor, analgesia, and local anesthesia. Based on the published references in the recent years, the advance on the identification of adulterants and quality evaluation as well as the influence factors on the quality of toad venom was summarized to improve the quality standards and promote the level of quality control of toad venom and its preparations.


Assuntos
Venenos de Anfíbios/farmacologia , Bufanolídeos/normas , Alcaloides Indólicos/normas , Materia Medica/normas , Animais , Bufanolídeos/farmacologia , Bufonidae , China , Alcaloides Indólicos/farmacologia , Controle de Qualidade
18.
J Asian Nat Prod Res ; 18(10): 966-75, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27244089

RESUMO

A series of tetrandrine derivatives were designed and synthesized using Suzuki coupling reaction. Eleven targeted compounds with over 50% inhibition against HL60 and A549 human cancer cell lines at 10 µM were further evaluated for the in vitro antitumor activities by MTT or SRB assay. The biological results revealed that some compounds exhibited potent antitumor activities. Thiophene derivative 6 and acetylphenyl derivative 5 were the most active ones against HL60 and A549 cell lines, with IC50 values less than 5 µM, which thus could be considered as useful candidate for further development of new antitumor agents.


Assuntos
Antineoplásicos/síntese química , Benzilisoquinolinas/síntese química , Benzilisoquinolinas/farmacologia , Desenho de Fármacos , Antineoplásicos/química , Antineoplásicos/farmacologia , Benzilisoquinolinas/química , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Células HL-60 , Humanos , Estrutura Molecular , Relação Estrutura-Atividade
19.
Yao Xue Xue Bao ; 51(5): 780-5, 2016 05.
Artigo em Zh | MEDLINE | ID: mdl-29877966

RESUMO

The study established the 1H NMR-based fingerprinting and analyzed 8 batches of Huangqi injection solution.1H NMR-based fingerprinting of both primary and secondary metabolites of Huangqi injection were established, and the 1H-1H chemical shift correlation spectroscopy (COSY) and 1H-13C chemical shift correlation spectroscopy (HSQC) were used to identify the chemical components in Huangqi injection solution. Coupled with similarity analysis and relative content determination,8 batches of Huangqi injection solution were analyzed. Twenty-five metabolites (both primary and secondary) were identified, and the significant differences were found in the chemical composition among these Huangqi samples. The content and content variation of the primary metabolites were much higher than those of the secondary metabolites, which was the major cause of the uniformity of the Huangqi injections. The results on the quality variations of Huangqi injections in this study will serve as a basis for improving the quality control.


Assuntos
Medicamentos de Ervas Chinesas/análise , Astragalus propinquus , Injeções , Espectroscopia de Ressonância Magnética , Espectroscopia de Prótons por Ressonância Magnética
20.
Biochim Biophys Acta ; 1843(6): 1188-95, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24631505

RESUMO

Lin28 is a small RNA-binding protein that plays an important role in regulating developmental timing, stem cell reprogramming, and oncogenesis. However, the significance of the effect of post-translational modifications on Lin28 activity is not fully understood. In this study, we demonstrated that PCAF directly interacted with and acetylated Lin28. We also showed that the acetylation of Lin28 can be specifically reversed by the deacetylase SIRT1. These findings suggest that the PCAF/SIRT1 balance plays an important role in regulating Lin28 activity. Furthermore, we found that the cold shock domain of Lin28 is the major target of PCAF-mediated acetylation, which leads to a severe reduction in the Lin28 protein levels and an increase in the level of mature let-7a. This study provides the first demonstration that post-translational modification regulates Lin28 activity during let-7a biogenesis and sheds light on the regulation of Lin28 in ES cells and carcinogenesis.


Assuntos
Processamento de Proteína Pós-Traducional , Proteínas de Ligação a RNA/metabolismo , Sirtuína 1/metabolismo , Fatores de Transcrição de p300-CBP/metabolismo , Acetilação , Western Blotting , Imunofluorescência , Células HEK293 , Humanos , Imunoprecipitação , Luciferases/metabolismo , Mutagênese Sítio-Dirigida , Mutação/genética , RNA Mensageiro/genética , Proteínas de Ligação a RNA/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sirtuína 1/genética , Fatores de Transcrição de p300-CBP/genética
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