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1.
Mikrochim Acta ; 191(5): 232, 2024 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-38565740

RESUMO

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.


Assuntos
Dopamina , Suor , Humanos , Elétrons
2.
Foodborne Pathog Dis ; 20(3): 110-119, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36893329

RESUMO

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.


Assuntos
Produtos da Carne , Carne Vermelha , Rosa , Animais , Bovinos , Staphylococcus aureus , Rosa/química , Carne Vermelha/microbiologia , Antibacterianos/farmacologia
3.
World J Surg Oncol ; 20(1): 286, 2022 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-36071524

RESUMO

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.


Assuntos
Coledocolitíase , Hemangioma , Neoplasias Pancreáticas , Criança , Coledocolitíase/patologia , Hemangioma/patologia , Humanos , Lactente , Pâncreas/irrigação sanguínea , Pâncreas/diagnóstico por imagem , Pâncreas/cirurgia , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/cirurgia , Doenças Raras/patologia
4.
Mikrochim Acta ; 189(7): 247, 2022 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-35676546

RESUMO

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.


Assuntos
Quitosana , Óxido de Zinco , Quitosana/química , Técnicas Eletroquímicas/métodos , Eletrodos , Tiametoxam
5.
Analyst ; 144(10): 3405-3413, 2019 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-30994646

RESUMO

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.

6.
Mikrochim Acta ; 186(11): 688, 2019 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-31595361

RESUMO

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.

7.
Br J Cancer ; 118(3): 405-415, 2018 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-29384529

RESUMO

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.


Assuntos
Diferenciação Celular/genética , Proteína HMGA2/genética , Proteínas de Homeodomínio/genética , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia , Antineoplásicos/farmacologia , Proliferação de Células/genética , Sobrevivência Celular/genética , Dimetil Sulfóxido/farmacologia , Sequestradores de Radicais Livres/farmacologia , Expressão Gênica , Técnicas de Silenciamento de Genes , Granulócitos/fisiologia , Células HL-60 , Proteínas de Homeodomínio/metabolismo , Humanos , Células K562 , Monócitos/fisiologia , Cultura Primária de Células , RNA Mensageiro/metabolismo , Tretinoína/farmacologia , Regulação para Cima
8.
Plant Physiol ; 170(3): 1524-34, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26739233

RESUMO

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.


Assuntos
Alquil e Aril Transferases/genética , Arabidopsis/genética , Regulação da Expressão Gênica de Plantas/genética , Proteínas de Plantas/genética , Pólen/genética , Sequências Reguladoras de Ácido Nucleico/genética , Arabidopsis/citologia , Arabidopsis/metabolismo , Citocininas/farmacologia , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Microscopia Confocal , Mutação , Motivos de Nucleotídeos/genética , Reguladores de Crescimento de Plantas/farmacologia , Plantas Geneticamente Modificadas , Plumbaginaceae/genética , Pólen/citologia , Regiões Promotoras Genéticas/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sítio de Iniciação de Transcrição
9.
Anal Biochem ; 530: 68-74, 2017 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-28483576

RESUMO

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%.


Assuntos
Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Impressão Molecular/métodos , Fragmentos de Peptídeos/química , Polímeros/química , Vacina Antirrábica/análise , Soroalbumina Bovina/análise , Animais , Bovinos , Chlorocebus aethiops , Eletrodos , Peroxidase do Rábano Silvestre/química , Peroxidase do Rábano Silvestre/metabolismo , Humanos , Peróxido de Hidrogênio/química , Limite de Detecção , Reprodutibilidade dos Testes , Soroalbumina Bovina/química , Soroalbumina Bovina/isolamento & purificação , Espectroscopia de Infravermelho com Transformada de Fourier , Células Vero
10.
Luminescence ; 32(7): 1116-1122, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28422395

RESUMO

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%.


Assuntos
Alcaloides de Cinchona/análise , Técnicas Eletroquímicas/instrumentação , Nanopartículas/química , 2,2'-Dipiridil/análogos & derivados , 2,2'-Dipiridil/química , Acrilamidas/química , Alcaloides de Cinchona/sangue , Alcaloides de Cinchona/química , Reagentes de Ligações Cruzadas/química , Técnicas Eletroquímicas/métodos , Ouro/química , Humanos , Limite de Detecção , Medições Luminescentes/instrumentação , Medições Luminescentes/métodos , Magnetismo , Membranas Artificiais , Impressão Molecular , Compostos Organometálicos/química , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Espectrofotometria Infravermelho , Estereoisomerismo
11.
J Clin Biochem Nutr ; 60(2): 136-142, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28366994

RESUMO

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.

12.
Angew Chem Int Ed Engl ; 56(36): 10845-10849, 2017 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-28686804

RESUMO

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. In vitro and in vivo experiments indicate that the nanodrug significantly alleviates side effects and improves therapeutic efficacy of ATO on CML and xenograft tumor model.


Assuntos
Antineoplásicos/farmacologia , Trióxido de Arsênio/farmacologia , Receptor 2 de Folato/antagonistas & inibidores , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Nanopartículas/química , Albumina Sérica Humana/química , Animais , Antineoplásicos/química , Trióxido de Arsênio/química , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Receptor 2 de Folato/metabolismo , Humanos , Células K562 , Leucemia Mielogênica Crônica BCR-ABL Positiva/metabolismo , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Camundongos , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Relação Estrutura-Atividade
13.
Analyst ; 140(13): 4702-7, 2015 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-25962832

RESUMO

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.


Assuntos
Técnicas de Química Analítica/instrumentação , Doxiciclina/análise , Membranas Artificiais , Impressão Molecular , Polímeros/síntese química , Doxiciclina/química , Eletroquímica , Medições Luminescentes , Espectrometria de Massas , Polimerização , Polímeros/química
14.
Plant Cell ; 23(3): 961-72, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21447790

RESUMO

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.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Relógios Circadianos , Flores/metabolismo , Regiões Promotoras Genéticas , Fatores de Transcrição/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Proteínas de Ligação a DNA/metabolismo , Flores/genética , Flores/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas , Fotoperíodo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Fatores de Transcrição/metabolismo , Transgenes
15.
Int J Med Sci ; 11(8): 788-95, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24936141

RESUMO

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.


Assuntos
Desenvolvimento Embrionário/genética , Hipocampo/crescimento & desenvolvimento , Histona Desacetilase 2/biossíntese , Neurogênese/genética , Animais , Embrião de Mamíferos , Regulação da Expressão Gênica no Desenvolvimento , Hipocampo/metabolismo , Histona Desacetilase 2/genética , Neurônios/metabolismo , Ratos
16.
Beijing Da Xue Xue Bao Yi Xue Ban ; 46(3): 366-72, 2014 Jun 18.
Artigo em Chinês | MEDLINE | ID: mdl-24943012

RESUMO

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.


Assuntos
Dieta , Vitamina A/administração & dosagem , Vitamina A/sangue , Animais , Antropometria , Peso Corporal , Criança , Pré-Escolar , China , Estudos Transversais , Feminino , Frutas , Inquéritos Epidemiológicos , Humanos , Masculino , Leite , Inquéritos Nutricionais , Estado Nutricional , Prevalência , Verduras , Deficiência de Vitamina A/epidemiologia
17.
Artigo em Inglês | MEDLINE | ID: mdl-38716548

RESUMO

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.

18.
Anal Chim Acta ; 1289: 342210, 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38245201

RESUMO

Alkaline phosphatase (ALP) is a major biomarker for clinical diagnosis, but detection methods of ALP are limited in sensitivity and selectivity. In this paper, a novel method for ALP determination is proposed. A photoelectrochemical (PEC) sensor was prepared by growing UiO-tetratopic tetrakis (4-carbox-yphenyl) porphyrin (TCPP) in situ between layered Ti3C2 through a one-pot hydrothermal method. The obtained Schottky heterojunction photoelectric material Ti3C2@UiO-TCPP not only has a large light absorption range but also greatly improves the efficiency of photogenerated electron hole separation and thereby enhances sensitivity for PEC detection. The phosphate group on the phosphorylated polypeptide was utilized to form a Zr-O-P bond with the zirconium ion on UiO-66, and then photocurrent decreases due to the steric hindrance effect of phosphorylated polypeptides, that is, the hindrance of electron transfer between the photoelectric material and a solution. The specific interaction between ALP and phosphorylated polypeptides shears the bond between phosphate and zirconium ion on UiO-66 in the peptides then weakens the hindrance effect and increases the photocurrent, thus realizing ALP detection. The linear range of ALP is 0.03-10,000 U·L-1, and the detection limit is 0.012 U·L-1. The method is highly sensitive and selective, and has been applied in detection of ALP in serum samples.


Assuntos
Técnicas Biossensoriais , Estruturas Metalorgânicas , Fosfopeptídeos , Ácidos Ftálicos , Fosfatase Alcalina/química , Titânio/química , Zircônio/química , Corantes , Fosfatos , Técnicas Biossensoriais/métodos , Limite de Detecção , Técnicas Eletroquímicas/métodos
19.
Life (Basel) ; 13(11)2023 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-38004357

RESUMO

The introduction of plasmids into Agrobacterium cells is one of the key steps in the Agrobacterium-mediated transformation of plants for gene editing applications. Depending on chromosomal background, some Agrobacterium strains exhibit a very low transformation efficiency, which results in a low number of colonies for subsequent screening and thus limits the potential for automated high-throughput transformation processes, especially with low copy or large plasmids. This study demonstrates improvements of transformation frequency by modifying the competent cell preparation process and optimizing electroporation parameters for two Agrobacterium strains. The competent cell preparation process was modified by prolonging bacterial growth in the log phase and optimizing the endpoint cell density for cell harvest which resulted in a significant cell yield increase and transformation frequency improvement. Optimization of electroporation by fine-tuning the parameters not only resulted in a 30-fold transformation frequency increase but also revealed a strain-dependent requirement for field strength and electric pulse length. To further improve transformation of a recalcitrant strain, different concentrations of dimethyl sulfoxide (DMSO) in recovery medium were examined. The study revealed an important role of DMSO in transformed cell recovery, with 5% DMSO resulting in the highest transformation frequency. The significant improvements in Agrobacterium transformation frequency addressed a critical bottleneck towards establishing a high throughput process.

20.
Zhongguo Fei Ai Za Zhi ; 26(7): 515-522, 2023 Jul 20.
Artigo em Chinês | MEDLINE | ID: mdl-37653015

RESUMO

BACKGROUND: The three-dimensional (3D) can assist in planning lung segmentectomy. 3D reconstruction software based on artificial intelligence algorithm is gradually applied in clinic. The aim of this study was to evaluate the accuracy and safety of 3D reconstruction assisted planning of thoracoscopic segmentectomy. METHODS: A total of 90 patients admitted to Department of Thoracic Surgery of Lanzhou University Second Hospital were evaluated for thoracoscopic segmentectomy. Before operation, artificial intelligence 3D reconstruction software was used to make 3D lung images and conduct preoperative planning. Surgical videos were saved during the operation and perioperative data were recorded. Video recordings of 38 patients were selected to explore the effectiveness of artificial intelligence 3D reconstruction for surgical planning. The results of artificial intelligence 3D reconstruction and Mimics 21 software reconstruction were compared with the actual results in the operation, and the detection and classification ability of bronchus and blood vessels of the two reconstruction methods were compared. RESULTS: All the 90 patients underwent artificial intelligence 3D reconstruction planning, including 57 patients (63.3%) with single lung segmentectomy and 33 patients (36.7%) with combined sub-segmentectomy. The accuracy of artificial intelligence 3D reconstruction for lesion localization was 100.0%, and the accuracy of computed tomography (CT) was 94.4% (85/90). The detection accuracy of artificial intelligence 3D reconstruction and Mimics 21 software was 92.1% (35/38) and 89.5% (34/38), and the anatomic typing accuracy was 89.5% (34/38) and 84.2% (32/38), and the total accuracy was 76.3% (29/38) and 71.1% (27/38). In the comparative observation of 38 surgical videos and reconstructed images, the consistent rates of target segment planning, surgical approach, artery dissection, vein dissection and bronchial dissection for preoperative planning using artificial intelligence 3D reconstruction were 92.1% (35/38), 92.1% (35/38), 89.5% (34/38), 86.8% (33/38) and 94.7% (36/38). The overall planning operational consistency rate was 68.4% (26/38). CONCLUSIONS: It is accurate and safe to use artificial intelligence 3D reconstruction to assist planning thoracoscopic segmentectomy.


Assuntos
Inteligência Artificial , Neoplasias Pulmonares , Humanos , Imageamento Tridimensional , Pneumonectomia , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/cirurgia , Software
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