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Two-dimensional room-temperature intrinsic ferromagnetic semiconductors have attracted widespread attention due to their applications in spintronic devices. However, it is difficult for the material to have a Curie temperature above room temperature according to the Mermin-Wagner theorem. By using the method of band engineering, we design a new promising two-dimensional room-temperature intrinsic ferromagnetic semiconductor Cr2XP (X = P, As, Sb) with large magnetization. The formation of a semiconducting gap for Cr2XP is discussed in terms of hybridization, occupation and distribution of electronic states and charge transfer. Large magnetic moments of about 6.16-6.37µB originate from the occupation of Cr-d electrons in the crystal field. Competition between Cr-d-Cr-d and Cr-d-X-p-Cr-d exchange interactions leads to the emergence of a ferromagnetic order phase. Furthermore, Curie temperatures, approaching 278 K, 464 K and 1590 K for Cr2P2, Cr2AsP and Cr2SbP, are estimated by employing Monte Carlo simulations based on the Heisenberg model. The magnetic anisotropy energy of Cr2XP is discussed using magnetic second-order perturbation theory. In addition, Cr2XP possesses excellent thermodynamic, dynamical, thermal and mechanical stabilities and can overcome its own gravity to retain its planar structure without the support of the substrate. These above-mentioned advantages will offer some valuable insights into two-dimensional intrinsic ferromagnetic semiconductor Cr2XP in spintronic devices.
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The interaction between environmental factors affecting honey bees is of growing concern due to their potential synergistic effects on bee health. Our study investigated the interactive impact of Varroa destructor and chlorothalonil on workers' survival, fat body morphology, and the expression of gene associated with detoxification, immunity, and nutrition metabolism during their adult stage. We found that both chlorothalonil and V. destructor significantly decreased workers' survival rates, with a synergistic effect observed when bees were exposed to both stressors simultaneously. Morphological analysis of fat body revealed significant alterations in trophocytes, particularly a reduction in vacuoles and granules after Day 12, coinciding with the transition of the bees from nursing to other in-hive work tasks. Gene expression analysis showed significant changes in detoxification, immunity, and nutrition metabolism over time. Detoxification genes, such as CYP9Q2, CYP9Q3, and GST-D1, were downregulated in response to stressor exposure, indicating a potential impairment in detoxification processes. Immune-related genes, including defensin-1, Dorsal-1, and Kayak, exhibited an initially upregulation followed by varied expression patterns, suggesting a complex immune response to stressors. Nutrition metabolism genes, such as hex 70a, AmIlp2, VGMC, AmFABP, and AmPTL, displayed dynamic expression changes, reflecting alterations in nutrient utilization and energy metabolism in response to stressors. Overall, these findings highlight the interactive and dynamic effects of environmental stressor on honey bees, providing insights into the mechanisms underlying honey bee decline. These results emphasize the need to consider the interactions between multiple stressors in honey bee research and to develop management strategies to mitigate their adverse effects on bee populations.
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Nitrilos , Varroidae , Animales , Abejas/parasitología , Abejas/efectos de los fármacos , Varroidae/fisiología , Varroidae/efectos de los fármacos , Nitrilos/toxicidad , Cuerpo Adiposo/metabolismo , Cuerpo Adiposo/efectos de los fármacos , Fungicidas Industriales/toxicidadRESUMEN
Methidathion (MTDT), a common organophosphorus pesticide with high insecticidal activity, is widely used for pest control. However, the misuse of MTDT leads to widespread residues and endangers human health. Therefore, it is crucial to develop a simple and highly sensitive method for the detection of MTDT residues. Herein, ZIF-90/MnO2/g-C3N4/Fe3O4 composite particles were synthesized: The MnO2 nanosheets could absorb the energy of the excited g-C3N4 to quench the ECL of g-C3N4 while ZIF-90 acted as a mimetic enzyme to catalyze the formation of thiocholine from MTDT. The thiocholine caused the reduction of MnO2 to Mn2+, restoring the ECL signal of g-C3N4. Combined with molecular imprinting technique, an electrochemiluminescence sensor was constructed for the determination of MTDT. The determination range was 1.00 × 10-9 ~ 7.00 × 10-7 g/L, and the detection limit was 6.58 × 10-10 g/L. Structurally similar organophosphorus pesticides showed no cross-reactivity. The method has high sensitivity and specificity, and has been successfully applied to the determination of MTDT residue in fruits with recoveries in the range 93.75% ~ 102.37%.
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Técnicas Electroquímicas , Límite de Detección , Mediciones Luminiscentes , Compuestos de Manganeso , Compuestos Organotiofosforados , Óxidos , Compuestos de Manganeso/química , Técnicas Electroquímicas/métodos , Mediciones Luminiscentes/métodos , Óxidos/química , Compuestos Organotiofosforados/análisis , Compuestos Organotiofosforados/química , Impresión Molecular , Grafito/química , Zeolitas/química , Insecticidas/análisis , Compuestos de Nitrógeno/química , Nanopartículas de Magnetita/química , Nitrilos/químicaRESUMEN
A novel ternary heterojunction material In2O3/In2S3/ZnIn2S4 was synthesized, and a photoelectrochemical sensor was fabricated for the non-invasive test of dopamine (DA) in sweat. In2O3 multihollow microtubules were synthesized and then In2S3 was formed on their surface to construct a type-I heterojunction between In2S3 and In2O3. ZnIn2S4 was further introduced to form a Z-scheme heterojunction between In2S3/ZnIn2S4. Under photoexcitation, the photogenerated holes of In2O3 transferred to the valence band of In2S3, superimposed with the holes produced by In2S3, leads to a significantly higher photocatalytic oxidation capacity of In2O3/In2S3/ZnIn2S4 ternary composites than that of In2O3/In2S3. The Z-scheme heterojunction accelerates the transfer of photogenerated electrons accumulated on the type-I heterojunction. In the presence of DA, it is rapidly oxidized into polydopamine (PDA) by In2O3/In2S3, and the benzoquinone groups of PDA compete for the photogenerated electrons to reduce the current in the external circuit, whereby DA determination is achieved. Owing to the combination of type-I and Z-scheme heterojunction, the sensor showed extremely high sensitivity, with a detection limit of 3.94 × 10-12 mol/L. It is one of the most sensitive methods for DA detection reported and has been applied to the determination of DA in human sweat.
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Dopamina , Sudor , Humanos , ElectronesRESUMEN
Staphylococcus aureus is a common foodborne pathogen and spoilage bacterium in meat products. To develop a natural preservative for meat products, this study revealed the antibacterial activity and mechanism of Rosa roxburghii Tratt pomace crude extract (RRPCE) against S. aureus, and applied RRPCE to the preservation of cooked beef. The diameter of inhibition zone, minimum inhibitory concentration (MIC), and minimum bactericide concentration of RRPCE against S. aureus were 15.85 ± 0.35 to 16.21 ± 0.29 mm, 1.5 mg/mL, and 3 mg/mL, respectively. The growth curve of S. aureus was completely stalled by treatment with RRPCE at 2 MIC. RRPCE results in the decrease of intracellular adenosine 5'-triphosphate (ATP) content, depolarization of cell membrane, leakage of cell fluid including nucleic acid and protein, and destruction of cell membrane integrity and cell morphology. During storage, RRPCE significantly reduced S. aureus viable counts, pH, and total volatile basic nitrogen of cooked beef compared with untreated samples (p < 0.05). In addition, RRPCE could significantly increase the redness (a*) value, decrease lightness (L*) and yellowness (b*) values, and slow down the color change of cooked beef (p < 0.05). These findings suggest that RRPCE can effectively inhibit S. aureus, and has the potential as a natural preservative for the preservation of cooked beef.
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Productos de la Carne , Carne Roja , Rosa , Animales , Bovinos , Staphylococcus aureus , Rosa/química , Carne Roja/microbiología , Antibacterianos/farmacologíaRESUMEN
BACKGROUND: Visceral hemangiomatosis is a benign tumor (rarer than hemangioma) that has not been reported to occur in the pancreas, duodenum, or choledoch. It can be easily confused with other pancreatic tumors or choledocholithiasis. Herein, we describe a case of a child with pancreaticoduodenal and choledochal hemangiomatosis and the key characteristics for the accurate diagnosis of pancreatic tumors based on previous reports and our findings. CASE PRESENTATION: We report a case of a 2-year and 9-month-old child who presented with repeated and fluctuating jaundice for 3 months with a history of endoscopic stone removal in a local hospital, following the diagnosis of choledocholithiasis. An abdominal computed tomography revealed a previously undiagnosed pancreatic head tumor and celio-mesenteric trunk (a rare vascular variation). This was misdiagnosed as a pancreatic neuroendocrine tumor. Since the patient's parents refused FNA biopsy and insisted on surgery, pancreaticoduodenectomy was performed; however, postoperatively, the child was correctly diagnosed with pancreaticoduodenal and choledochal hemangiomatosis. Although the patient was in good condition and had gained 4 kg in weight 3 months postoperatively, pancreaticoduodenectomy could have been avoided if an accurate diagnosis had been established before or during the operation. CONCLUSION: Our report highlights the difficulty in diagnosing visceral hemangiomatosis. Radiologists, endoscopists, and surgeons should consider this possibility in cases of repeated and fluctuating jaundice that cannot be explained by choledocholithiasis alone.
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Coledocolitiasis , Hemangioma , Neoplasias Pancreáticas , Niño , Coledocolitiasis/patología , Hemangioma/patología , Humanos , Lactante , Páncreas/irrigación sanguínea , Páncreas/diagnóstico por imagen , Páncreas/cirugía , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/patología , Neoplasias Pancreáticas/cirugía , Enfermedades Raras/patologíaRESUMEN
A molecularly imprinted photoelectrochemical sensor with high sensitivity and stable structure was constructed and applied to detect thiamethoxam pesticide. ZnO/Bi2O3/Bi2S3 heterojunction photoelectric material was formed on the fluorine-doped tin oxide (FTO) electrode by seed layer growth, drip coating, and in situ ion exchange. A chitosan-imprinted polymer membrane was prepared using chitosan as the functional monomer, glutaraldehyde as the cross-linking agent, and thiamethoxam as the template molecule. The photoelectric material was characterized by X-ray diffraction, scanning electron microscopy, and energy dispersive x-ray spectroscopy analyses. The electron transfer mechanism of Z-type heterojunction was verified by ultraviolet-visible curve and Mott-Schottky curve. When thiamethoxam was re-adsorbed on the imprinted membrane, the current recorded at 0 V (vs. Ag/AgCl) was reduced because the thiamethoxam molecule blocked the electron transfer. The molecularly imprinted sensor exhibited a linear relationship to thiamethoxam concentration in the range from 7.0 × 10-13 mol/L to 7.0 × 10-10 mol/L and the detection limit was 3.32 × 10-13 mol/L, which is lower than the values reported by other detection methods. Most pesticides, such as propoxur and isoprocarband carbaryl, do not interfere with the determination. The sensor also showed good practicability and suitability for the determination of trace thiamethoxam in environmental water and soil leaching solutions, with a recovery of 99.6-102.1% (RSD < 3.74%). A novel molecularly imprinted photoelectrochemical (MI-PEC) sensor with high sensitivity and selectivity for the determination of thiamethoxam (TMX) was developed. A Z-type heterojunction ZnO/Bi2O3/Bi2S3 photoelectric material was synthesized for the first time. The MI-PEC sensor was prepared with ZnO/Bi2O3/Bi2S3 as the sensitive material and MI membrane as the recognition element. The sensor exhibits an extremely sensitive response to thiamethoxam with a detection limit of 3.32 × 10-13 mol/L due to the excellent photoelectrochemical properties of ZnO/Bi2O3/Bi2S3.
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Quitosano , Óxido de Zinc , Quitosano/química , Técnicas Electroquímicas/métodos , Electrodos , TiametoxamRESUMEN
A novel ultrasensitive photoelectrochemical sensor for benzoyl peroxide (BPO) was constructed under visible light irradiation. A novel nanostructured material made of molecularly imprinted polymer (MIP)-modified silver iodide nanoparticle-titanium dioxide nanotube arrays (AgINPs-TiO2 NTs) was designed as a photoactive electrode (denoted as MIP@AgINPs-TiO2 NTs). AgI-sensitized TiO2 nanotube arrays were prepared by a simple dissolution-precipitation-calcination process and then employed as a matrix to graft the MIP recognition element. Such a newly designed molecularly imprinted photoelectrochemical sensor exhibits high sensitivity and selectivity for the determination of BPO. The photoelectrochemical analysis is highly linear over the BPO concentration range from 1 × 10-12 mol L-1 to 5 × 10-10 mol L-1 with a detection limit of 2.53 × 10-13 mol L-1 (S/N = 3, n = 11). The sensor designed based on a low cost and highly sensitive assay was successfully applied in the determination of BPO in spiked samples.
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A molecularly imprinted polymer photoelectrochemical (MIP-PEC) sensor based on bismuth sulfide (Bi2S3) is described for the determination of the plasticizer dioctyl phthalate (DOP). Bi2S3 was used as the photoelectrical converter of the sensor, and visible light was utilized as the excitation source. The molecular imprinting film was prepared through the electropolymerization of monomers in the presence of DOP. Under optimal experimental conditions, the photoelectrochemical response was linearly proportional to the logarithm of the DOP concentration in the 0.5-70 pM DOP concentration range, and the detection limit was 0.1 pM. The method is highly stable and reproducible. It was applied to the determination of DOP in spiked water samples. Graphical abstract A novel molecularly imprinted photoelectrochemical sensor with high sensitivity and high selectivity based on Bi2S3 was developed for dioctyl phthalate detection. Bi2S3 was firstly used as a photoelectric converter in photoelectrochemical sensor to improve the sensitivity of the sensor. Combining photocurrent measurement with molecular imprinting technique makes the sensor highly selective.
RESUMEN
BACKGROUND: High-mobility group AT-hook 2 (HMGA2) may serve as an architectural transcription factor, and it can regulate a range of normal biological processes including proliferation and differentiation. Upregulation of HMGA2 expression is correlated to the undifferentiated phenotype of immature leukaemic cells. However, the underlying mechanism of HMGA2-dependent myeloid differentiation blockage in leukaemia is unknown. METHODS: To reveal the role and mechanism of HMGA2 in differentiation arrest of myeloid leukaemia cells, the quantitative expression of HMGA2 and homeobox A9 (HOXA9) was analysed by real-time PCR (qRT-PCR). The regulatory function of HMGA2 in blockage of differentiation in human myeloid leukaemia was investigated through in vitro assays (XTT assay, May-Grünwald-Giemsa, flow cytometry analysis and western blot). RESULTS: We found that the expression of HMGA2 and HOXA9 was reduced during the process of granulo-monocytic maturation of acute myeloid leukaemia (AML) cells, knockdown of HMGA2 promotes terminal (granulocytic and monocytic) differentiation of myeloid leukaemia primary blasts and cell lines, and HOXA9 was significantly downregulated in leukaemic cells with knockdown of HMGA2. Downregulation of HOXA9 in myeloid leukaemia cells led to increased differentiation capacity in vitro. CONCLUSIONS: Our data suggest that increased expression of HMGA2 represents a possible new mechanism of myeloid differentiation blockage of leukaemia. Aberrant expression of HMGA2 may enhance HOXA9-dependent leukaemogenesis and myeloid leukaemia phenotype. Disturbance of the HMGA2-HOXA9 pathway is probably a therapeutic strategy in myeloid leukaemia.
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Diferenciación Celular/genética , Proteína HMGA2/genética , Proteínas de Homeodominio/genética , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patología , Antineoplásicos/farmacología , Proliferación Celular/genética , Supervivencia Celular/genética , Dimetilsulfóxido/farmacología , Depuradores de Radicales Libres/farmacología , Expresión Génica , Técnicas de Silenciamiento del Gen , Granulocitos/fisiología , Células HL-60 , Proteínas de Homeodominio/metabolismo , Humanos , Células K562 , Monocitos/fisiología , Cultivo Primario de Células , ARN Mensajero/metabolismo , Tretinoina/farmacología , Regulación hacia ArribaRESUMEN
Flowering plant sperm cells transcribe a divergent and complex complement of genes. To examine promoter function, we chose an isopentenyltransferase gene known as PzIPT1. This gene is highly selectively transcribed in one sperm cell morphotype of Plumbago zeylanica, which preferentially fuses with the central cell during fertilization and is thus a founding cell of the primary endosperm. In transgenic Arabidopsis (Arabidopsis thaliana), PzIPT1 promoter displays activity in both sperm cells and upon progressive promoter truncation from the 5'-end results in a progressive decrease in reporter production, consistent with occurrence of multiple enhancer sites. Cytokinin-dependent protein binding motifs are identified in the promoter sequence, which respond with stimulation by cytokinin. Expression of PzIPT1 promoter in sperm cells confers specificity independently of previously reported Germline Restrictive Silencer Factor binding sequence. Instead, a cis-acting regulatory region consisting of two duplicated 6-bp Male Gamete Selective Activation (MGSA) motifs occurs near the site of transcription initiation. Disruption of this sequence-specific site inactivates expression of a GFP reporter gene in sperm cells. Multiple copies of the MGSA motif fused with the minimal CaMV35S promoter elements confer reporter gene expression in sperm cells. Similar duplicated MGSA motifs are also identified from promoter sequences of sperm cell-expressed genes in Arabidopsis, suggesting selective activation is possibly a common mechanism for regulation of gene expression in sperm cells of flowering plants.
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Transferasas Alquil y Aril/genética , Arabidopsis/genética , Regulación de la Expresión Génica de las Plantas/genética , Proteínas de Plantas/genética , Polen/genética , Secuencias Reguladoras de Ácidos Nucleicos/genética , Arabidopsis/citología , Arabidopsis/metabolismo , Citocininas/farmacología , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Microscopía Confocal , Mutación , Motivos de Nucleótidos/genética , Reguladores del Crecimiento de las Plantas/farmacología , Plantas Modificadas Genéticamente , Plumbaginaceae/genética , Polen/citología , Regiones Promotoras Genéticas/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Sitio de Iniciación de la TranscripciónRESUMEN
To improve the sensitivity of the molecular imprinting sensor detection of protein, a new strategy based on enzyme amplification was proposed. The determination of bovine serum albumin (BSA) was achieved by using the epitope imprinted techniques coupling with electrochemical measurement method. Nonapeptide, separated from BSA, was selected as a template molecule to prepare the molecularly imprinted polymer (MIP) film, and it could bind with the cavities of the MIP. By the use of epitope imprinted techniques, BSA can be recognized by the MIP via the nonapeptide on the surface of BSA. The synthesized horseradish peroxidase-labeled nonapeptide (HRP-nonapeptide) can also be recognized by the MIP. After the competitive reaction between HRP-nonapeptide and BSA, the enzymatic reaction derived from labeled HRP on the H2O2-hydroquinone system make the electrochemical current of hydroquinone change, then the concentration of BSA can be indirectly determined. BSA in the range of 1.0-150 ng/mL exhibited a linear relationship with the differential pulse voltammetric current variation and the detection limit was 0.02 ng/mL. The sensor has high sensitivity, good selectivity, and reproducibility. It has been applied to the determination of residual bovine serum albumin in human rabies vaccine with the recovery rate of 98.3%-102.5%.
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Técnicas Biosensibles/métodos , Técnicas Electroquímicas/métodos , Impresión Molecular/métodos , Fragmentos de Péptidos/química , Polímeros/química , Vacunas Antirrábicas/análisis , Albúmina Sérica Bovina/análisis , Animales , Bovinos , Chlorocebus aethiops , Electrodos , Peroxidasa de Rábano Silvestre/química , Peroxidasa de Rábano Silvestre/metabolismo , Humanos , Peróxido de Hidrógeno/química , Límite de Detección , Reproducibilidad de los Resultados , Albúmina Sérica Bovina/química , Albúmina Sérica Bovina/aislamiento & purificación , Espectroscopía Infrarroja por Transformada de Fourier , Células VeroRESUMEN
A novel molecular imprinting electrochemiluminescence sensor for detecting chiral cinchonine molecules was developed with a molecularly imprinted polymer membrane on the surfaces of magnetic microspheres. Fe3 O4 @Au nanoparticles modified with 6-mercapto-beta-cyclodextrin were used as a carrier, cinchonine as a template molecule, methacrylic acid as a functional monomer and N,N'-methylenebisacrylamide as a cross-linking agent. Cinchonine was specifically recognized by the 6-mercapto-beta-cyclodextrin functional molecularly imprinted polymer and detected based on enhancement of the electrochemiluminescence intensity caused by the reaction of tertiary amino structures of cinchonine molecules with Ru(bpy)32+ . Cinchonine concentrations of 1 × 10-10 to 4 × 10-7 mol/L showed a good linear relationship with changes of the electrochemiluminescence intensity, and the detection limit of the sensor was 3.13 × 10-11 mol/L. The sensor has high sensitivity and selectivity, and is easy to renew. It was designed for detecting serum samples, with recovery rates of 98.2% to 107.6%.
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Alcaloides de Cinchona/análisis , Técnicas Electroquímicas/instrumentación , Nanopartículas/química , 2,2'-Dipiridil/análogos & derivados , 2,2'-Dipiridil/química , Acrilamidas/química , Alcaloides de Cinchona/sangre , Alcaloides de Cinchona/química , Reactivos de Enlaces Cruzados/química , Técnicas Electroquímicas/métodos , Oro/química , Humanos , Límite de Detección , Mediciones Luminiscentes/instrumentación , Mediciones Luminiscentes/métodos , Magnetismo , Membranas Artificiales , Impresión Molecular , Compuestos Organometálicos/química , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Espectrofotometría Infrarroja , EstereoisomerismoRESUMEN
Maternal folate and vitamin B12 deficiency predict poor pregnancy outcome. To improve pregnancy outcomes in rural area of China, we investigate rural women's folic acid supplementation (FAS) status and the associations between maternal vitamin B status during the first trimester and subsequent adverse pregnancy outcomes. We collected the questionnaire information and drew 5 ml of blood from 309 early pregnant rural women. The birth outcomes were retrieved from medical records after delivery. Out of the total, 257 had taken FAS, including 50 before conception (group A) and 207 during the first trimester (group B). The concentration of plasma folate and the RBC folate supplementation groups were obviously higher than that of no-supplementation group (group N, p<0.01). The mean vitamin B12 levels in FAS group were significantly higher than those in groups N and B (p<0.05). Women who delivered SGA or premature infants had reduced plasma folate levels (p<0.05) compared with controls. The multiple linear regression models revealed that RBC folate levels affected the infant birth weight (p<0.01) and birth length (p<0.05). In conclusion, FAS can significantly improve plasma folate and RBC folate levels in childbearing-age women and reduce the risk of subsequent adverse pregnancy outcomes.
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Arsenic trioxide (ATO, As2 O3 ) is currently used to treat acute promyelocytic leukemia. However, expanding its use to include high-dose treatment of other cancers is severely hampered by serious side effects on healthy organs. To address these limitations, we loaded ATO onto folate (FA)-labeled human serum albumin (HSA) pretreated with glutathione (GSH) based on the low pH- and GSH-sensitive arsenic-sulfur bond, and we termed the resulting smart nanodrug as FA-HSA-ATO. FA-HSA-ATO could specifically recognize folate receptor-ß-positive (FRß+) chronic myeloid leukemia (CML) cells, resulting in more intracellular accumulation of ATO. Furthermore, the nanodrug could upregulate FRß expression in CML cancer cells and xenograft tumor model, facilitating even more recruitment and uptake of FRß-targeting drugs. Inâ vitro and inâ vivo experiments indicate that the nanodrug significantly alleviates side effects and improves therapeutic efficacy of ATO on CML and xenograft tumor model.
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Antineoplásicos/farmacología , Trióxido de Arsénico/farmacología , Receptor 2 de Folato/antagonistas & inhibidores , Leucemia Mielógena Crónica BCR-ABL Positiva/tratamiento farmacológico , Nanopartículas/química , Albúmina Sérica Humana/química , Animales , Antineoplásicos/química , Trióxido de Arsénico/química , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Receptor 2 de Folato/metabolismo , Humanos , Células K562 , Leucemia Mielógena Crónica BCR-ABL Positiva/metabolismo , Leucemia Mielógena Crónica BCR-ABL Positiva/patología , Ratones , Neoplasias Experimentales/tratamiento farmacológico , Neoplasias Experimentales/metabolismo , Neoplasias Experimentales/patología , Relación Estructura-ActividadRESUMEN
A new molecularly imprinted sensor was developed based on an electroluminescent molecularly imprinted polymer (MIP) membrane and used for doxycycline determination. The MIP was prepared by electropolymerization of pyrogallol doped with alizarin red. An electrochemiluminescence (ECL) signal was produced by the oxidation of the poly-pyrogallol polymer and reaction with alizarin red. The luminescence intensity was enhanced by doxycycline molecules which were re-adsorbed in cavities in MIP due to the energy transfer of the doxycycline oxidized intermediate to alizarin red. The changes of ECL intensities were linear with the concentrations of doxycycline in the range of 2 × 10(-10) to 5 × 10(-8) mol L(-1). The detection limit was 5.17 × 10(-11) mol L(-1). This method was utilized to determine doxycycline residuals in fish muscles with satisfactory results.
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Técnicas de Química Analítica/instrumentación , Doxiciclina/análisis , Membranas Artificiales , Impresión Molecular , Polímeros/síntesis química , Doxiciclina/química , Electroquímica , Mediciones Luminiscentes , Espectrometría de Masas , Polimerizacion , Polímeros/químicaRESUMEN
BROTHER OF LUX ARRHYTHMO (BOA) is a GARP family transcription factor in Arabidopsis thaliana and is regulated by circadian rhythms. Transgenic lines that constitutively overexpress BOA exhibit physiological and developmental changes, including delayed flowering time and increased vegetative growth under standard growing conditions. Arabidopsis circadian clock protein CIRCADIAN CLOCK ASSOCIATED1 (CCA1) binds to the evening element of the BOA promoter and negatively regulates its expression. Furthermore, the period of BOA rhythm was shortened in cca1-11, lhy-21 (for LATE ELONGATED HYPOCOTYL), and cca1-11 lhy-21 genetic backgrounds. BOA binds to the promoter of CCA1 through newly identified promoter binding sites and activates the transcription of CCA1 in vivo and in vitro. In transgenic Arabidopsis lines that overexpress BOA, the period length of CCA1 rhythm was increased and the amplitude was enhanced. Rhythmic expression of other clock genes, including LHY, GIGANTEA (GI), and TIMING OF CAB EXPRESSION1 (TOC1), was altered in transgenic lines that overexpress BOA. Rhythmic expression of BOA was also affected in mutant lines of toc1-1, gi-3, and gi-4. Results from these studies indicate that BOA is a critical component of the regulatory circuit of the circadian clock.
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Proteínas de Arabidopsis/genética , Arabidopsis/genética , Relojes Circadianos , Flores/metabolismo , Regiones Promotoras Genéticas , Factores de Transcripción/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Proteínas de Unión al ADN/metabolismo , Flores/genética , Flores/crecimiento & desarrollo , Regulación de la Expresión Génica de las Plantas , Fotoperiodo , Plantas Modificadas Genéticamente/genética , Plantas Modificadas Genéticamente/metabolismo , Factores de Transcripción/metabolismo , TransgenesRESUMEN
BACKGROUND: Histone acetylation, which is a chromatin modification of histone tails, can dynamically regulate the expression of various genes in normal development. HDAC2 is a negative regulatory factor of acetylation and closely related to learning and memory. NSE is a nerve marker and vital for maintaining physiological functions in nervous system. Currently, few studies associated with the expression pattern of HDAC2 in postnatal rat hippocampus have been reported. This study aimed to explore the temporal and spatial expression pattern of HDAC2, helping to reveal the expression characteristics of HDAC2 during postnatal neuronal maturation. MATERIALS AND METHODS: With NSE as a biomarker of neuronal maturation at postnatal days 1, 3, 7 and weeks 2, 4, and 8 (P1D, P3D, P7D, P2W, P4W, P8W), the expression patterns of HDAC2 in rat hippocampus were examined using real-time PCR and western blotting. Additionally, the subcellular distribution of HDAC2 was analysed by immunofluorescence. RESULTS: We found that HDAC2 was highly expressed in the neonatal period and decreased gradually. HDAC2 expression was widely distributed in neurons of hippocampal CA1, CA3 and DG regions and gradually shifted from the nucleus to the cytoplasm during postnatal development. Altogether, the expression of HDAC2 decreased gradually with different subcellular localizations throughout development. CONCLUSIONS: The observed results indicate that the expression levels of HDAC2 become lower and with different subcellular localizations in neurons during hippocampal neuronal maturation, suggesting the specific expression characteristics of HDAC2 might play an important role during postnatal learning-memory function and development.
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Desarrollo Embrionario/genética , Hipocampo/crecimiento & desarrollo , Histona Desacetilasa 2/biosíntesis , Neurogénesis/genética , Animales , Embrión de Mamíferos , Regulación del Desarrollo de la Expresión Génica , Hipocampo/metabolismo , Histona Desacetilasa 2/genética , Neuronas/metabolismo , RatasRESUMEN
OBJECTIVE: To study the relationship between dietary vitamin A intake and plasma vitamin A concentration, and establish the theoretical basis for dietary intake predicting vitamin A nutritional status. METHODS: By using cluster sampling, 492 children aged 2-7 years in kindergartens in Banan district of Chongqing were selected. A cross-sectional nutrition and health survey was conducted, including the clinical examination, anthropometry, laboratory test and dietary survey. RESULTS: Among the children surveyed, 229 were boys, and 263 girls, the mean age was (4.54 ± 0.87) years, height (107.50 ± 7.20) cm, and weight (18.42 ± 3.41) kg, the mean value of plasma vitamin A was (1.04 ± 0.30) µmol/L. The prevalence of marginal vitamin A deficiency (MVAD) was 43.5%. No cases of severe clinical vitamin A deficiency were found (plasma vitamin A ≤ 0.35 µmol/L). Clinical examination found no conjunctiva, corneaor skin abnormalities, and no Bitot's spots. Prevalence of the last two weeks colds were 27.4% (135/492), no diarrhea and other gastrointestinal or digestive diseases were found. The proportion of insufficient dietary vitamin A intake (<600 µg RE/d) was as high as 50.0%. By using correlation analysis, plasma retinol concentrations were related to dietary vitamin A intake (r=0.162, P<0.001), and to dietary energy intake (r=0.107, P=0.017). After adjustment for the effects of other non-dietary factors on vitamin A deficiency, the multivariate logistic regression showed that vitamin A-rich foods of liver intake=0 g/d (OR=1.95, 95% CI: 1.05-3.61, P=0.034), vitamin A-rich fruits intake=0 g/d (OR=1.55, 95% CI: 1.03-2.33, P=0.034), vitamin A-rich vegetables intake<200 g/d (OR=3.47, 95% CI: 1.37-8.75, P=0.009) were important risk factors of vitamin A deficiency. But we had not found the correlation between the intake of meat, eggs and milk and vitamin A deficiency. CONCLUSION: Dietary factors may be the major risk factor of vitamin A deficiency in the three kindergartens. The dietary vitamin A intakes are significantly related to plasma retinol concentrations, and the vitamin A-rich foods intakes can predict the body's vitamin A nutritional status.
Asunto(s)
Dieta , Vitamina A/administración & dosificación , Vitamina A/sangre , Animales , Antropometría , Peso Corporal , Niño , Preescolar , China , Estudios Transversales , Femenino , Frutas , Encuestas Epidemiológicas , Humanos , Masculino , Leche , Encuestas Nutricionales , Estado Nutricional , Prevalencia , Verduras , Deficiencia de Vitamina A/epidemiologíaRESUMEN
BACKGROUND: Uncontrolled inflammation plays an important role in the initiation and progression of tumors. The repeated circulation and continuous stimulation of gallbladder epithelium caused by gallstones is an important risk factor for gallbladder cancer. METHODS: To study pathogenesis, samples were collected for chronic cholecystitis caused by gallstones and early and advanced gallbladder cancer with gallstones and subjected to RNA-seq analysis. Gene Ontology and Kyoto Gene and Genome Encyclopedia analyses were used to elucidate the protein-protein interaction network and identify differentially expressed genes. RESULTS: Nine potential molecular markers, VTN, CHAD, AKR1C4, ABCC2, AOX1, ADH1A, ADH1C, PLA2G2A, and CYP4F3, with elevated expression gradients in cholecystitis and early and advanced gallbladder cancer, were identified. Using qPCR and immunohistochemistry on clinical tissues, we confirmed three factors, VTN, CYP4F3, and AOX1, to be worthy of further research. To demonstrate that these three genes are potential molecular markers for gallbladder cancer, their cellular biological functions were confirmed in gallbladder cancer cell lines through siRNA transfection. CONCLUSION: The potential molecular markers CYP4F3, VTN, and AOX1 for cholecystitis and different stages of gallbladder cancer were identified. Further studies on differentially expressed genes vital in gallbladder cancer progression can help provide potential targets for the early diagnosis and treatment of gallbladder cancer.