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1.
Nature ; 587(7832): 139-144, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-33116310

RESUMEN

Zygotic genome activation (ZGA) is the first transcription event in life1. However, it is unclear how RNA polymerase is engaged in initiating ZGA in mammals. Here, by developing small-scale Tn5-assisted chromatin cleavage with sequencing (Stacc-seq), we investigated the landscapes of RNA polymerase II (Pol II) binding in mouse embryos. We found that Pol II undergoes 'loading', 'pre-configuration', and 'production' during the transition from minor ZGA to major ZGA. After fertilization, Pol II is preferentially loaded to CG-rich promoters and accessible distal regions in one-cell embryos (loading), in part shaped by the inherited parental epigenome. Pol II then initiates relocation to future gene targets before genome activation (pre-configuration), where it later engages in full transcription elongation upon major ZGA (production). Pol II also maintains low poising at inactive promoters after major ZGA until the blastocyst stage, coinciding with the loss of promoter epigenetic silencing factors. Notably, inhibition of minor ZGA impairs the Pol II pre-configuration and embryonic development, accompanied by aberrant retention of Pol II and ectopic expression of one-cell targets upon major ZGA. Hence, stepwise transition of Pol II occurs when mammalian life begins, and minor ZGA has a key role in the pre-configuration of transcription machinery and chromatin for genome activation.


Asunto(s)
Regulación del Desarrollo de la Expresión Génica/genética , Genoma/genética , ARN Polimerasa II/metabolismo , Cigoto/metabolismo , Alelos , Animales , Cromatina/genética , Cromatina/metabolismo , Embrión de Mamíferos/citología , Embrión de Mamíferos/enzimología , Embrión de Mamíferos/metabolismo , Epigenoma/genética , Femenino , Masculino , Herencia Materna/genética , Ratones , Ratones Endogámicos C57BL , Oocitos/enzimología , Oocitos/metabolismo , Regiones Promotoras Genéticas/genética , ARN Polimerasa II/genética , Cigoto/citología , Cigoto/enzimología
2.
J Am Chem Soc ; 146(22): 15198-15208, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38743271

RESUMEN

Various monovalent cations are employed to construct metal halide perovskites with various structures and functionalities. However, perovskites based on highly polar A-site cations have seldom been reported. Here, a novel hybrid 0D (NH4)x(OH3)3-xInCl6 perovskite with highly polar hydronium OH3+ cations is introduced in this study. Upon doping with Sb3+, hybrid 0D (NH4)x(OH3)3-xInCl6 single crystals exhibited highly efficient broadband yellowish-green (550 nm) and red (630 nm) dual emissions with a PLQY of 86%. The dual emission arises due to Sb3+ occupying two sites within the crystal lattice that possess different polarization environments, leading to distinct Stokes shift energies. The study revealed that lattice polarity plays a significant role in the self-trapped exciton emission of Sb3+-doped perovskites, contributing up to 25% of the Stokes shift energy for hybrid 0D (NH4)x(OH3)3-xInCl6:Sb3+ as a secondary source, in addition to the Jahn-Teller deformation. These findings highlight the potential of Sb3+-doped perovskites for achieving tunable broadband emission and underscore the importance of lattice polarity in determining the emission properties of perovskite materials.

3.
Molecules ; 29(5)2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38474659

RESUMEN

Currently, in the ongoing development of the tobacco industry, a large amount of tobacco rhizomes is discarded as waste. These wastes are usually disposed of through incineration or burial. However, these tobacco wastes still have some economic value. High-purity nicotine has a promising market outlook as the primary raw material for electronic cigarette liquid. Nicotine is not only found in tobacco leaves but also in the rhizomes of tobacco plants. This study presents a method for treating tobacco waste and extracting high-purity nicotine from it. After mixing the raw material powder and entrainer in specific ratios, as much of the nicotine in tobacco roots can be extracted as possible using supercritical carbon dioxide extraction. The effects of temperature, the ratio of the entrainer, and the volume fraction of ethanol in the entrainer on the nicotine yield in supercritical fluid extraction (SFE) at 25 MPa for 120 min were discussed. By using 90% ethanol (a raw material mass-to-volume ratio of 1:5) as the entrainer, we obtained the highest nicotine yield of 0.49% at 65 °C. Meanwhile, the purity of the crude extract was 61.71%, and after purification, it increased to 97.57%. In this way, we can not only obtain nicotine with market value but also further reduce the harm to the environment caused by tobacco waste disposal.


Asunto(s)
Cromatografía con Fluido Supercrítico , Sistemas Electrónicos de Liberación de Nicotina , Rizoma , Nicotina , Dióxido de Carbono , Nicotiana , Etanol , Cromatografía con Fluido Supercrítico/métodos
4.
Int J Mol Sci ; 24(16)2023 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-37628832

RESUMEN

The aim of this study was to investigate the chemical composition and antioxidant capacity of various polar fractions obtained from Dendrobium fimbriatum Hook (DH). First, a 90% ethanol-aqueous extract of DH (CF) was subjected to sequential fractionation using different organic solvents, resulting in the isolation of a methylene chloride fraction (DF), an ethyl acetate fraction (EF), an n-butanol fraction (BF), and a remaining water fraction (WF) after condensation. Additionally, the CF was also subjected to column chromatography via a D101 macroreticular resin column, eluted with ethanol-aqueous solution to yield six fractions (0%, 20%, 40%, 60%, 80%, and 100%). UPLC-Q-Exactive Orbitrap-MS/MS analysis identified a total of 47 chemical compounds from these polar fractions, including fatty acids, amino acids, phenolic acids, flavonoids, organic heterocyclic molecules, and aromatic compounds. Moreover, DF, EF, and the 60%, 80%, and 100% ethanol-aqueous fractions had higher total phenol content (TPC) and total flavonoid content (TFC) values and greater 2,2'-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS-) and 1,1-diphenyl-2-picrylhydrazyl (DPPH)-scavenging abilities. In H2O2-induced HepG2 cells, the aforementioned fractions could increase the activities of antioxidative enzymes NAD(P)H: quinone oxidoreductase 1 (NQO1), superoxide dismutase (SOD), heme oxygenase-1 (HO-1) and catalase (CAT), stimulate glutathione (GSH) synthesis by increasing the activities of glutamic acid cysteine ligase (GCL) and glutathione synthetase (GS), regulate GSH metabolism by increasing glutathione peroxidase (GSH-Px) and glutathione reductase (GR) activities, and reduce levels of reactive oxygen species (ROS) and malondialdehyde (MDA). Furthermore, the antioxidative stress effect of the DH fractions was found to be positively correlated with the activation of nuclear factor-erythroid 2-related factor 2 (Nrf2) protein and the presence of antioxidative chemical constituents. In conclusion, this study highlights the efficacy of both liquid-liquid extraction and macroporous resin purification techniques in the enrichment of bioactive compounds from natural food resources. The comprehensive analysis of chemical constituents and antioxidant effects of different polar fractions from Dendrobium fimbriatum Hook contributes to the understanding of its potential application in functional foods and nutraceuticals.


Asunto(s)
Antioxidantes , Dendrobium , Antioxidantes/farmacología , Peróxido de Hidrógeno , Espectrometría de Masas en Tándem , Glutatión
5.
J Pediatr Hematol Oncol ; 44(2): e580-e584, 2022 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-34862352

RESUMEN

RATIONALE: Juvenile myelomonocytic leukemia (JMML) is a rare hematopoietic disorder, which is more rarely accompanied by monosomy 5 or deletion of the long arm of chromosome 5q (-5/5q-) or monosomy 5 (5q-/-5), and hemophagocytic lymphohistiocytosis (HLH) is a rare, uncontrolled hyperinflammation condition, which is more rarely secondary to JMML. Up to now, only a few cases of JMML with -5/5q- and HLH secondary to JMML were described. Here we described an extremely rare case of HLH second to JMML with 5q-. PATIENT CONCERNS: The patient had multiple cafe-au-lait-spots at birth and was found that NF1 gene mutation was positive. At his 6 years old, he developed hepatosplenomegaly, anemia, thrombocytopenia, monocyte count 4.12×109/L in peripheral blood, 13% blasts in peripheral blood, and 11% blasts in bone marrow, without BCR/ABL rearrangement, combining with positive NF1 gene mutation, he was diagnosed as JMML. In the bone marrow, there was chromosomal abnormalities with -5/5q-. In the treatment, HLH occurred. DIAGNOSES: The patient was diagnosed as secondary HLH to JMML. INTERVENTIONS: The patient received the chemotherapy treatment of the improved diffuse alveolar hemorrhage protocol, and meanwhile, he prepared for hematopoietic stem cell transplantation. Then on the basis of anti-infection, symptomatic and supportive therapy, he was commenced the treatment according to the HLH-2004 protocol. OUTCOMES: He had a partial response, manifesting that his fever resolved, but the blood coagulation function did not improve, and the severe thrombocytopenia remained. Then, the parents refused the continual treatment, and the child died of intracranial hemorrhage 3 months after the diagnosis of JMML. LESSONS: JMML and HLH were relatively easy to diagnose based on clinical and laboratory results. Due to the low incidence of JMML with -5/5q- and HLH secondary to JMML, no clinical practice guidelines for the treatment of the disease have been established yet. The clinical data of a case of HLH secondary to JMML with 5q- were analyzed, and relevant studies were studied.


Asunto(s)
Anemia , Leucemia Mielomonocítica Juvenil , Linfohistiocitosis Hemofagocítica , Trombocitopenia , Anemia/complicaciones , Médula Ósea , Niño , Humanos , Recién Nacido , Leucemia Mielomonocítica Juvenil/complicaciones , Leucemia Mielomonocítica Juvenil/genética , Leucemia Mielomonocítica Juvenil/terapia , Linfohistiocitosis Hemofagocítica/complicaciones , Linfohistiocitosis Hemofagocítica/genética , Masculino , Monosomía , Trombocitopenia/complicaciones
6.
Cellulose (Lond) ; 29(4): 2223-2240, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35125686

RESUMEN

ABSTRACT: The COVID-19 pandemic outbreak has resulted in the massive fabrication of disposable surgical masks. As the accumulation of discarded face masks represents a booming threat to the environment, here we propose a solution to reuse and upcycle surgical masks according to one of the cornerstones of the circular economy. Specifically, the non-woven cellulosic layer of the masks is used as an environmentally sustainable and highly porous solid support for the controlled deposition of catalytically active metal-oxide nanoparticles. The native cellulosic fibers from the surgical masks are decorated by titanium dioxide (TiO2), iron oxide (FexOy), and cobalt oxide (CoOx) nanoparticles following a simple and scalable approach. The abundant surface -OH groups of cellulose enable the controlled deposition of metal-oxide nanoparticles that are photocatalytically active or shown enzyme-mimetic activities. Importantly, the hydrophilic highly porous character of the cellulosic non-woven offers higher accessibility of the pollutant to the catalytically active surfaces and high retention in its interior. As a result, good catalytic activities with long-term stability and reusability are achieved. Additionally, developed free-standing hybrids avoid undesired media contamination effects originating from the release of nanoscale particles. The upcycling of discarded cellulosic materials, such as the ones of masks, into high-added-value catalytic materials, results an efficient approach to lessen the waste´s hazards of plastics while enhancing their functionality. Interestingly, this procedure can be extended to the upcycling of other systems (cellulosic or not), opening the path to greener manufacturing approaches of catalytic materials. GRAPHICAL ABSTRACT: A novel approach to upcycle discarded cellulosic surgical masks is proposed, providing a solution to reduce the undesired accumulation of discarded face masks originating from the COVID-19 pandemic. The non-woven cellulosic layer formed by fibers is used as solid support for the controlled deposition of catalytically active titanium dioxide (TiO2), iron oxide (FexOy), and cobalt oxide (CoOx) nanoparticles. Cellulosic porous materials are proven useful for the photocatalytic decomposition of organic dyes, while their peroxidase-like activity opens the door to advanced applications such as electrochemical sensors. The upcycling of cellulose nonwoven fabrics into value-added catalytic materials lessens the waste´s hazards of discarded materials while enhancing their functionality. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s10570-022-04441-9.

7.
Int J Mol Sci ; 23(22)2022 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-36430220

RESUMEN

TiO2:Au-based photocatalysis represents a promising alternative to remove contaminants of emerging concern (CECs) from wastewater under sunlight irradiation. However, spherical Au nanoparticles, generally used to sensitize TiO2, still limit the photocatalytic spectral band to the 520 nm region, neglecting a high part of sun radiation. Here, a ligand-free synthesis of TiO2:Au nanostars is reported, substantially expanding the light absorption spectral region. TiO2:Au nanostars with different Au component sizes and branching were generated and tested in the degradation of the antibiotic ciprofloxacin. Interestingly, nanoparticles with the smallest branching showed the highest photocatalytic degradation, 83% and 89% under UV and visible radiation, together with a threshold in photocatalytic activity in the red region. The applicability of these multicomponent nanoparticles was further explored with their incorporation into a porous matrix based on PVDF-HFP to open the way for a reusable energy cost-effective system in the photodegradation of polluted waters containing CECs.


Asunto(s)
Oro , Nanopartículas del Metal , Agua , Catálisis
8.
Ann Hematol ; 100(9): 2215-2228, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34089385

RESUMEN

To explore the differences in the clinical features, treatment responses, and outcomes among children, adolescents, and adults with chronic myeloid leukemia in the chronic phase (CML-CP) receiving imatinib as first-line therapy. Data from children (0-8 years for girls and 0-10 years for boys), adolescents (9-19 years for girls and 11-19 years for boys), and adults (age ≥ 20 years) with newly diagnosed CML-CP receiving imatinib as first-line therapy between 2006 and 2019 were retrospectively reviewed. In total, 135 children (cohort 1), 189 adolescents (cohort 2), and 658 adults (cohort 3: age 20-39 years, n = 305; cohort 4: age 40-59 years, n = 270; and cohort 5: age 60-83 years, n = 83) were included in this study. When compared with children, adolescents showed a significantly higher white blood cell count (P = 0.033) and basophil percentage in peripheral blood (P = 0.002) and a significantly higher prevalence of splenomegaly (P = 0.004). Both children and adolescents presented with more aggressive clinical features than adults. During median follow-ups of 28 months (range, 3-161 months) in children, 33 months (range, 3-152 months) in adolescents, and 48 months (range, 3-157 months) in adults, multivariate analysis showed that children and adolescents had higher probabilities of achieving complete cytogenetic response, major molecular response, and molecular response4.5. Notably, compared with not only adults (cohort 3 vs. cohort 1: HR = 2.03 [1.03, 3.98], P = 0.040; cohort 4 vs. cohort 1: HR = 2.15 [1.07, 4.33], P = 0.033; cohort 5 vs. cohort 1: HR = 4.22 [1.94, 9.15], P < 0.001) but also adolescents (cohort 2 vs. cohort 1: HR = 2.36 [1.18, 4.72], P = 0.015), children had significantly longer failure-free survival. Age was not associated with progression-free survival or overall survival. Although they exhibited more aggressive clinical features at diagnosis, both children and adolescents achieved superior treatment responses than adults. Adolescents showed even more adverse features and a poor FFS than children.


Asunto(s)
Antineoplásicos/uso terapéutico , Mesilato de Imatinib/uso terapéutico , Leucemia Mielógena Crónica BCR-ABL Positiva/tratamiento farmacológico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Femenino , Humanos , Lactante , Leucemia Mielógena Crónica BCR-ABL Positiva/diagnóstico , Masculino , Persona de Mediana Edad , Inhibidores de Proteínas Quinasas/uso terapéutico , Estudios Retrospectivos , Insuficiencia del Tratamiento , Resultado del Tratamiento , Adulto Joven
9.
J Am Chem Soc ; 142(30): 13130-13135, 2020 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-32614184

RESUMEN

It remains difficult to control the morphology of two-dimensional (2D) materials via direct chemical vapor deposition (CVD) growth. In particular, off-equilibrium (kinetic) growth may produce flakes with non-Wulff shapes (e.g., high-index edges, symmetrical shapes, etc.), which are potentially useful; however, a general controllable approach for the kinetic growth of 2D materials is currently lacking. In this work, we pushed the CVD growth of 2D MoS2 into deep kinetic regime, by using potassium chloride (KCl) as catalyst and plasma pretreatment on growth substrates. The unprecedented nonequilibrium high-index faceting and unusual high-symmetry shapes in 2D materials have been realized. The growth mechanism of high-index facets is rationalized based on the theory of kinetic instability on crystal surfaces. This new vapor-liquid-adatom-solid (VLAS) growth mechanism-synergistic capture of multiple vapor phase molecules by the catalyst particles on corners and the oversaturated adatom diffusion along adjacent edges can offer great opportunities for shape engineering on 2D materials. The high-quality, rapid, and controllable synthesis of high-index facets (edges) and other non-Wulff shapes of 2D transition metal dichalcogenides will benefit the developments in 2D materials.

10.
Phys Rev Lett ; 125(24): 246102, 2020 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-33412019

RESUMEN

The formation, propagation, and structure of nanoscale cracks determine the failure mechanics of engineered materials. Herein, we have captured, with atomic resolution and in real time, unit cell-by-unit cell lattice-trapped cracking in two-dimensional (2D) rhenium disulfide (ReS_{2}) using in situ aberration corrected scanning transmission electron microscopy (STEM). Our real time observations of atomic configurations and corresponding strain fields in propagating cracks directly reveal the atomistic fracture mechanisms. The entirely brittle fracture with non-blunted crack tips as well as perfect healing of cracks have been observed. The mode I fracture toughness of 2D ReS_{2} is measured. Our experiments have bridged the linear elastic deformation zone and the ultimate nm-sized nonlinear deformation zone inside the crack tip. The dynamics of fracture has been explained by the atomic lattice trapping model. The direct visualization on the strain field in the ongoing crack tips and the gained insights of discrete bond breaking or healing in cracks will facilitate deeper insights into how atoms are able to withstand exceptionally large strains at the crack tips.

11.
Anal Biochem ; 597: 113672, 2020 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-32135140

RESUMEN

Adulteration of high-quality meat with their cheaper counterparts can be minimized by rapid and reliable methods for detecting meat species. Here an isothermal cross-primer amplification (CPA) technique combined with colloidal gold nucleic acid test strips (CPA strips) was developed to differentiate cow, sheep, arctic fox, and pig meat. A simple primer design for multiplex differentiation using a universal single-labeled CPA primer system and four detection-level species-specific labeling primers were analyzed by colloidal gold-based test strip assay. Moreover, simultaneous detection of fox and pig meat on a double-test line strip was feasible. The CPA strip assay indicated a lower amounts sensitivity of 0.3 ng DNA when one targeted species was tested and a detection limit of 1% when arctic fox meat was detected in the meat mixtures. Using a minimal set of primers, this study provides a promising tool for detecting the species of different types of meat using a constant temperature amplification technology.


Asunto(s)
Contaminación de Alimentos/análisis , Carne/análisis , Técnicas de Amplificación de Ácido Nucleico , Ácidos Nucleicos/genética , Tiras Reactivas/química , Animales , Bovinos , Zorros , Ovinos , Porcinos
12.
Zhongguo Dang Dai Er Ke Za Zhi ; 22(1): 47-52, 2020 Jan.
Artículo en Zh | MEDLINE | ID: mdl-31948524

RESUMEN

OBJECTIVE: To study the influence of dasatinib treatment on body height in children with acute myeloid leukemia (AML). METHODS: A retrospective analysis was performed for the clinical data of 86 AML children aged <17 years. According to the treatment regimen, these children were divided into a conventional chemotherapy group and a dasatinib chemotherapy group. The 57 children in the conventional chemotherapy group were given conventional chemotherapy drugs without tyrosine kinase inhibitor, and the 29 children in the dasatinib chemotherapy group were given conventional chemotherapy drugs and dasatinib. The two groups were compared in terms of height standard deviation score (HtSDS) at the beginning of treatment and after treatment, as well as the change in HtSDS after 1 and 2 years of treatment. RESULTS: There was no significant difference in HtSDS between the conventional and dasatinib chemotherapy groups before treatment. Within the first two years of treatment, the dasatinib chemotherapy group had a similar change trend of HtSDS as the conventional chemotherapy group. Four children in the dasatinib chemotherapy group reached the final adult height during follow-up, which was significantly lower than the target height (P=0.044). In the conventional chemotherapy group, there was no significant difference between final adult height and target height. In the dasatinib chemotherapy group, the children in adolescence had a significant change in HtSDS after treatment (P=0.032). CONCLUSIONS: Dasatinib treatment may affect the final height of children with AML, and the use of dasatinib after the beginning of adolescence may lead to growth disorder, but dasatinib treatment has little effect on body height in the short-term treatment.


Asunto(s)
Estatura , Dasatinib/uso terapéutico , Leucemia Mieloide Aguda , Adolescente , Niño , Trastornos del Crecimiento , Humanos , Leucemia Mieloide Aguda/tratamiento farmacológico , Estudios Retrospectivos
13.
Can J Microbiol ; 61(11): 811-7, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26308702

RESUMEN

Porcine epidemic diarrhea (PED) is a highly contagious, enteric disease of swine caused by the porcine epidemic diarrhea virus (PEDV). To find a suitable ELISA method to assess the infection of PEDV and the effectiveness of vaccines, we developed and evaluated an indirect enzyme-linked immunosorbent assay (iELISA) based on a truncated recombinant spike (S) protein expressed in Escherichia coli. The parameters of the iELISA were optimized, and the cutoff value determined as 0.259 by analyzing optical density (OD) values of 80 PEDV negative sera confirmed by western blot. Repeatability tests revealed that the coefficients of variation of positive sera within and between runs were both less than 10%. Cross-reactivity assays demonstrated that iELISA was PEDV-specific. A virus neutralization test with sera of 7 different OD values showed a positive correlation between the OD values and virus neutralization. The results suggest this iELISA is specific, sensitive, and repeatable. Further studies should focus on the relationship between OD values of sera and its virus neutralization.


Asunto(s)
Anticuerpos Antivirales/sangre , Infecciones por Coronavirus/inmunología , Ensayo de Inmunoadsorción Enzimática/métodos , Virus de la Diarrea Epidémica Porcina/inmunología , Glicoproteína de la Espiga del Coronavirus/inmunología , Enfermedades de los Porcinos/inmunología , Animales , Anticuerpos Neutralizantes/sangre , Western Blotting , Infecciones por Coronavirus/virología , Reacciones Cruzadas , Femenino , Pruebas de Neutralización , Proteínas Recombinantes/inmunología , Reproducibilidad de los Resultados , Porcinos , Enfermedades de los Porcinos/virología
14.
Zhongguo Dang Dai Er Ke Za Zhi ; 17(2): 180-4, 2015 Feb.
Artículo en Zh | MEDLINE | ID: mdl-25760846

RESUMEN

OBJECTIVE: To assess the diagnostic value of the propranolol-exercise provocative test for growth hormone deficiency (GHD) in children. METHODS: This study included 120 children who received both the insulin provocative test and the propranolol-exercise provocative test due to short stature between January 2009 and March 2013. Growth hormone (GH) levels in venous blood were measured before and after the provocative test. Peak GH <10 ng/mL was defined as negative stimulation, while peak GH ≥10 ng/mL was defined as positive stimulation. The children whose peak GH levels were <10 ng/ mL after both tests were diagnosed with GHD. RESULTS: Twenty-nine (24.2%) of the 120 children with short stature were diagnosed with GHD. The positive rate in the insulin provocative test was 48.3%, versus 65.8% in the propranolol-exercise provocative test. The overall coincidence rate and positive coincidence rate of the two tests were 62.5% and 79.3%, respectively. The peak GH after the propranolol-exercise provocative test was significantly higher than that after the insulin provocative test (P<0.01). Peak GH occurred mostly at 30-60 minutes after the insulin provocative test, while that occurred mostly at 120 minutes after the propranolol-exercise provocative test. No adverse effects were observed in the propranolol-exercise provocative test. CONCLUSIONS: Coincidence rates in stimulating the secretion of GH are high between the propranolol-exercise provocative test and the insulin provocative test. Compared with the insulin provocative test, the propranolol-exercise provocative test is more likely to stimulate the secretion of GH. GHD can be clinically diagnosed by the insulin provocative test combined with the propranolol-exercise provocative test.


Asunto(s)
Hormona de Crecimiento Humana/deficiencia , Propranolol , Adolescente , Niño , Preescolar , Ejercicio Físico , Femenino , Hormona de Crecimiento Humana/sangre , Humanos , Insulina , Masculino
15.
Anal Chem ; 86(19): 9873-9, 2014 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-25211600

RESUMEN

Alkaline phosphatase (ALP) is an important diagnostic indicator for a number of human diseases since abnormal level of ALP is closely related to a variety of pathological processes; hence, the development of convenient and reliable assay methods for monitoring ALP is of great significance for medical sciences as well as biological diagnostics. Herein, we report the first ratiometric fluorescent sensing system for ALP. This sensing system consists of two components: the betaine-modified and positively charged polyethylenimine (PEI) and the negatively charged pyrene derivative containing one ALP-responsive phosphate group (Py-P, an aliphatic phosphate ester). In the absence of ALP, the two-component sensing system shows the excimer's emission of Py-P, since Py-P molecules complex with the positively charged polyelectrolyte via electrostatic interactions, leading to the formation of pyrene excimers. While in the presence of ALP, the phosphate moieties are cleaved from Py-P molecules due to the enzymatic reaction, thereby destroying the electrostatic interactions; as a result, the system displays the monomer emission of Py-P. This assay system is operable in aqueous media with a very low detection limit of 0.1 U/mL. The system is capable of detecting ALP in such biological fluid as serum, and this strategy may provide a new and effective approach for designing ratiometric sensing systems for detecting other biomolecules.


Asunto(s)
Fosfatasa Alcalina/sangre , Betaína/química , Colorantes Fluorescentes/química , Polietileneimina/química , Pirenos/química , Bioensayo , Humanos , Espectrometría de Fluorescencia/métodos , Electricidad Estática
16.
Zhongguo Dang Dai Er Ke Za Zhi ; 16(12): 1236-40, 2014 Dec.
Artículo en Zh | MEDLINE | ID: mdl-25523572

RESUMEN

OBJECTIVE: To study the effects of recombinant human growth hormone (r-hGH) replacement therapy on glucose and lipid metabolism and thyroid function in children with idiopathic short stature (ISS). METHODS: Forty-seven ISS children with a mean age of 10±3 years treated between January 2009 and January 2013 were enrolled. All children underwent r-hGH replacement therapy for 3-24 months and were followed up once every 3 months. Fasting blood glucose (FBG), insulin (INS), blood lipids and thyroid function were measured before treatment and after 0-1 and 1-2 years of treatment. RESULTS: After treatment with r-hGH, there were no significant changes in FBG, INS, insulin sensitivity index (ISI), and FBG/INS ratio (FGIR), but the FGIR showed a declining trend. The percentage of patients with FGIR<7 (a marker of insulin resistance) was 13% before treatment compared to 18% 1-2 years after treatment. The atherosclerosis index decreased after r-hGH treatment, but there were no significant changes in total cholesterol, triglyceride, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol and BMI. Furthermore, no significant change in thyroid function was observed after r-hGH therapy. CONCLUSIONS: r-hGH therapy can improve lipid metabolism, without significant impacts on thyroid function, FBG and INS. It seems to be a safe and reliable therapy for children with ISS. However, this therapy possibly reduces insulin sensitivity.


Asunto(s)
Glucosa/metabolismo , Trastornos del Crecimiento/tratamiento farmacológico , Terapia de Reemplazo de Hormonas , Hormona de Crecimiento Humana/uso terapéutico , Metabolismo de los Lípidos/efectos de los fármacos , Glándula Tiroides/fisiopatología , Adolescente , Glucemia/análisis , Niño , Preescolar , Femenino , Trastornos del Crecimiento/fisiopatología , Humanos , Insulina/sangre , Masculino , Glándula Tiroides/efectos de los fármacos
17.
World J Gastrointest Surg ; 16(2): 571-584, 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38463352

RESUMEN

BACKGROUND: The efficacy and safety of anti-tumor necrosis factor-α (TNF-α) monoclonal antibody therapy [adalimumab (ADA) and infliximab (IFX)] with therapeutic drug monitoring (TDM), which has been proposed for inflammatory bowel disease (IBD) patients, are still controversial. AIM: To determine the efficacy and safety of anti-TNF-α monoclonal antibody therapy with proactive TDM in patients with IBD and to determine which subtype of IBD patients is most suitable for proactive TDM interventions. METHODS: As of July 2023, we searched for randomized controlled trials (RCTs) and observational studies in PubMed, Embase, and the Cochrane Library to compare anti-TNF-α monoclonal antibody therapy with proactive TDM with therapy with reactive TDM or empiric therapy. Pairwise and network meta-analyses were used to determine the IBD patient subtype that achieved clinical remission and to determine the need for surgery. RESULTS: This systematic review and meta-analysis yielded 13 studies after exclusion, and the baseline indicators were balanced. We found a significant increase in the number of patients who achieved clinical remission in the ADA [odds ratio (OR) = 1.416, 95% confidence interval (CI): 1.196-1.676] and RCT (OR = 1.393, 95%CI: 1.182-1.641) subgroups and a significant decrease in the number of patients who needed surgery in the proactive vs reactive (OR = 0.237, 95%CI: 0.101-0.558) and IFX + ADA (OR = 0.137, 95%CI: 0.032-0.588) subgroups, and the overall risk of adverse events was reduced (OR = 0.579, 95%CI: 0.391-0.858) according to the pairwise meta-analysis. Moreover, the network meta-analysis results suggested that patients with IBD treated with ADA (OR = 1.39, 95%CI: 1.19-1.63) were more likely to undergo TDM, especially in comparison with patients with reactive TDM (OR = 1.38, 95%CI: 1.07-1.77). CONCLUSION: Proactive TDM is more suitable for IBD patients treated with ADA and has obvious advantages over reactive TDM. We recommend proactive TDM in IBD patients who are treated with ADA.

18.
Sci Total Environ ; 922: 171128, 2024 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-38395168

RESUMEN

This study comprehensively investigated the impact of dust storms (DSs) on downstream cities, by selecting representative DS events. In this paper, we discussed the characteristics of meteorological conditions, air pollutants, PM2.5 components, and their influence on sulfate formation mechanisms. During DSs, strong winds, reaching speeds of up to 10 m/s, led to significant increases in PM10 and PM2.5, with maximum concentrations of 2684.5 and 429 µg/m3, respectively. Primary gaseous pollutants experienced substantial reductions, with decline rates of 48.1, 34.9, 36.8, and 9.0 % for SO2, NO2, NH3, and CO, respectively. Despite a notable increase in PM2.5 concentrations, only 7.6 % of the total mass of PM2.5 was attributed to ionic and carbonaceous components, a much lower value than observed before the DSs (77.3 %). Concentrations of Fe, Ti, and Mn exhibited increases by factors of 6.5-14.1, 10.4-17.0, and 1.6-4.7, respectively. In contrast to the significant decrease of >76.2 % in nitrogen oxidation ratio (NOR), sulfur oxidation ratio (SOR) remained at a relatively high level, displaying a strong positive correlation with high concentrations of Fe, Mn, and Ti. Quantitative analysis revealed an average increase of 0.187 and 0.045 µg/m3 in sulfate from natural sources and heterogeneous generation, respectively. The heterogeneous reaction on mineral dust was closely linked to atmospheric humidity, radiation intensity, the form of metal existence, and concentrations of it. High concentrations of titanium dioxide and iron­manganese oxides in mineral dust promoted heterogeneous oxidation of SO2 through photocatalysis during the daytime and metal ion catalysis during the nighttime. This study establishes that the metal components in mineral dust promote heterogeneous sulfate formation, quantifies the yield of sulfate generated as a result, and provides possible mechanisms for heterogeneous sulfate formation.

19.
World J Gastroenterol ; 30(19): 2564-2574, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38817663

RESUMEN

BACKGROUND: Cell division cyclin 25C (CDC25C) is a protein that plays a critical role in the cell cycle, specifically in the transition from the G2 phase to the M phase. Recent research has shown that CDC25C could be a potential therapeutic target for cancers, particularly for hepatocellular carcinoma (HCC). However, the specific regulatory mechanisms underlying the role of CDC25C in HCC tumorigenesis and development remain incompletely understood. AIM: To explore the impact of CDC25C on cell proliferation and apoptosis, as well as its regulatory mechanisms in HCC development. METHODS: Hepa1-6 and B16 cells were transduced with a lentiviral vector containing shRNA interference sequences (LV-CDC25C shRNA) to knock down CDC25C. Subsequently, a xenograft mouse model was established by subcutaneously injecting transduced Hepa1-6 cells into C57BL/6 mice to assess the effects of CDC25C knockdown on HCC development in vivo. Cell proliferation and migration were evaluated using a Cell Counting Kit-8 cell proliferation assays and wound healing assays, respectively. The expression of endoplasmic reticulum (ER) stress-related molecules (glucose-regulated protein 78, X-box binding protein-1, and C/EBP homologous protein) was measured in both cells and subcutaneous xenografts using quantitative real-time PCR (qRT-PCR) and western blotting. Additionally, apoptosis was investigated using flow cytometry, qRT-PCR, and western blotting. RESULTS: CDC25C was stably suppressed in Hepa1-6 and B16 cells through LV-CDC25C shRNA transduction. A xenograft model with CDC25C knockdown was successfully established and that downregulation of CDC25C expression significantly inhibited HCC growth in mice. CDC25C knockdown not only inhibited cell proliferation and migration but also significantly increased the ER stress response, ultimately promoting ER stress-induced apoptosis in HCC cells. CONCLUSION: The regulatory mechanism of CDC25C in HCC development may involve the activation of ER stress and the ER stress-induced apoptosis signaling pathway.


Asunto(s)
Apoptosis , Carcinoma Hepatocelular , Movimiento Celular , Proliferación Celular , Estrés del Retículo Endoplásmico , Técnicas de Silenciamiento del Gen , Neoplasias Hepáticas , Ratones Endogámicos C57BL , Fosfatasas cdc25 , Animales , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Fosfatasas cdc25/metabolismo , Fosfatasas cdc25/genética , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Línea Celular Tumoral , Ratones , Humanos , ARN Interferente Pequeño/metabolismo , Masculino , Regulación Neoplásica de la Expresión Génica , Ensayos Antitumor por Modelo de Xenoinjerto , Carcinogénesis/genética
20.
Chemistry ; 19(3): 936-42, 2013 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-23197478

RESUMEN

Owing to the considerable significance of fluoride anions for health and environmental issues, it is of great importance to develop methods that can rapidly, sensitively and selectively detect the fluoride anion in aqueous media and biological samples. Herein, we demonstrate a robust fluorescent turn-on sensor for detecting the fluoride ion in a totally aqueous solution. In this study, a biocompatible hydrophilic polymer poly(ethylene glycol) (PEG) is incorporated into the sensing system to ensure water solubility and to enhance biocompatibility. tert-Butyldiphenylsilyl (TBDPS) groups were then covalently introduced onto the fluorescein moiety, which effectively quenched the fluorescence of the sensor. Upon addition of fluoride ion, the selective fluoride-mediated cleavage of the Si-O bond leads to the recovery of the fluorescein moiety, resulting in a dramatic increase in fluorescence intensity under visible light excitation. The sensor is responsive and highly selective for the fluoride anion over other common anions; it also exhibits a very low detection limit of 19 ppb. In addition, this sensor is operative in some real samples such as running water, urine, and serum and can accurately detect fluoride ions in these samples. The cytotoxicity of the sensor was determined to be Grade I toxicity according to United States Pharmacopoeia and ISO 10993-5, suggesting the very low cytotoxicity of the sensor. Moreover, it was found that the senor could be readily internalized by both HeLa and L929 cells and the sensor could be utilized to track fluoride level changes inside the cells.


Asunto(s)
Colorantes Fluorescentes/química , Fluoruros/análisis , Polietilenglicoles/química , Animales , Línea Celular Tumoral , Colorantes Fluorescentes/síntesis química , Colorantes Fluorescentes/farmacocinética , Células HeLa , Humanos , Iones/análisis , Ratones , Estructura Molecular , Polietilenglicoles/síntesis química , Polietilenglicoles/farmacocinética , Agua/química
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