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1.
Mediators Inflamm ; 2022: 3288262, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36110099

RESUMO

Postoperative cognitive dysfunction (POCD) is consequence of anesthesia and surgery that primarily affects older people. The prevention and treatment of POCD has drawn an increasing attention in recent decades. Here, we established the animal model mimicked POCD after femoral fracture surgery, and analyze the effect of acupuncture stimulation on postoperative cognitive function after femoral fracture surgery. Compared with the mock group, the cognitive function performance was significantly decreased both in the anaesthesia group and the surgery group, between which the symptoms were more severe in the surgery group. The peripheral inflammation response and the neuron impairment and inflammation response in the hippocampus were observed in the surgery group, but only peripheral inflammation response was detected in the anaesthesia group. These findings indicated the POCD was the synergistic outcome of anaesthesia and surgical stimulation but with different pathogenic mechanism. The surgery with mental tri-needles (surgery+MTN) group outperformed the surgery group in terms of cognitive function performance. The peripheral inflammation response and the neuron impairment and inflammation response in the hippocampus was significantly reduced by the electroacupuncture stimulation. Our findings indicated the protection of electroacupuncture form POCD after femoral fracture surgery is related to the inhibition of inflammation response and neuron impairment.


Assuntos
Eletroacupuntura , Fraturas do Fêmur , Complicações Cognitivas Pós-Operatórias , Animais , Fraturas do Fêmur/cirurgia , Hipocampo , Humanos , Inflamação/terapia , Neurônios , Complicações Pós-Operatórias/terapia
2.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(11): 3096-9, 2015 Nov.
Artigo em Zh | MEDLINE | ID: mdl-26978916

RESUMO

The biological drug of the calf-blood dialysate has various pharmacological effects. It can promote the oxygen and glucose uptake for the hypoxia cells, and has beneficial effects on the malfunction of the blood circulation and trophic disturbances in the brain, and the impairment of peripheral blood circulation. Furthermore, it is favorable to wound healing and can regulate the central nervous system. Adenosine monophosphate (AMP) is a main active ingredient of the biological drug. In this report, a fluorescence resonance energy transfer (FRET) sensor has been developed with ß-CD-capped ZnS QDs as energy donor and 3-hydroxyflavone (3-HF) as energy acceptor. The results showed that AMP can lead to the fluorescence quenching of the FRET sensor at 526 nm, and the Stern-Volmer curve between the fluorescence quenching and the concentrations of AMP present a satisfactory linearity with the correlation coefficient of 0.996. The developed sensor has successfully applied for determination of the AMP in the biological drug.


Assuntos
Monofosfato de Adenosina/análise , Produtos Biológicos/análise , Transferência Ressonante de Energia de Fluorescência , Animais , Bovinos
3.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(10): 2792-8, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25739227

RESUMO

At present, because the blending coal was taken in some power stations as the major fuel which has too complex physical and chemical characters to build accurate normal near infrared quantitative models in some cases, which brought difficulties for on-line electric coal calorific value detection. For this reason, it was carefully studied that the time domain and frequency domain properties of the power generation coal near infrared spectra, and was proposed that a new quantitative near infrared method named frequency domain self-adaption analysis. The first step, time domain near infrared spectra are converted into frequency domain near infrared signal by Fast Fourier Transform; The second step, the suitable frequency information range by means of valid spectra energy parameter ηE was obtained by this method; The third step, it was constructed that an information volume parameter which is formed by correlation coefficient, standard deviation spectra and coordinate of harmonic in frequency domain to initialize the regression model input parameters' position; Finally, the optimal model is established by way of discrete frequency domain scooping and synthesized performance function. At the same time, compared with the principle component regression, partial least squares regression, back propagation artificial network, support vector regression and partial least squares regression optimized by genetic algorithm models, it is acquired that a more accurate method which can effectively avoid over fitting and virtual effective models and has a very useful application prospect by verifying the electric coal calorific value. Additionally, this method can be used in other quantitative spectra analysis.

4.
Guang Pu Xue Yu Guang Pu Fen Xi ; 33(10): 2809-14, 2013 Oct.
Artigo em Zh | MEDLINE | ID: mdl-24409741

RESUMO

The environmental vulnerability retrieval is important to support continuing data. The spatial distribution of regional environmental vulnerability was got through remote sensing retrieval. In view of soil and vegetation, the environmental vulnerability evaluation index system was built, and the environmental vulnerability of sampling points was calculated by the AHP-fuzzy method, then the correlation between the sampling points environmental vulnerability and ETM + spectral reflectance ratio including some kinds of conversion data was analyzed to determine the sensitive spectral parameters. Based on that, models of correlation analysis, traditional regression, BP neural network and support vector regression were taken to explain the quantitative relationship between the spectral reflectance and the environmental vulnerability. With this model, the environmental vulnerability distribution was retrieved in the Yellow River Mouth Area. The results showed that the correlation between the environmental vulnerability and the spring NDVI, the September NDVI and the spring brightness was better than others, so they were selected as the sensitive spectral parameters. The model precision result showed that in addition to the support vector model, the other model reached the significant level. While all the multi-variable regression was better than all one-variable regression, and the model accuracy of BP neural network was the best. This study will serve as a reliable theoretical reference for the large spatial scale environmental vulnerability estimation based on remote sensing data.


Assuntos
Monitoramento Ambiental , Tecnologia de Sensoriamento Remoto , Rios , Meio Ambiente , Modelos Teóricos , Redes Neurais de Computação , Plantas , Análise de Regressão , Solo
5.
World J Clin Cases ; 11(18): 4368-4376, 2023 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-37449220

RESUMO

BACKGROUND: It is difficult and risky for patients with a single lung to undergo thoracoscopic segmental pneumonectomy, and previous reports of related cases are rare. We introduce anesthesia for Extracorporeal membrane oxygenation (ECMO)-assisted thoracoscopic lower lobe subsegmental resection in a patient with a single left lung. CASE SUMMARY: The patient underwent comprehensive treatment for synovial sarcoma of the right lung and nodules in the lower lobe of the left lung. Examination showed pulmonary function that had severe restrictive ventilation disorder, forced expiratory volume in 1 second of 0.72 L (27.8%), forced vital capacity of 1.0 L (33%), and maximal voluntary ventilation of 33.9 L (35.5%). Lung computed tomography showed a nodular shadow in the lower lobe of the left lung, and lung metastasis was considered. After multidisciplinary consultation and adequate preoperative preparation, thoracoscopic left lower lung lobe S9bii+S10bii combined subsegmental resection was performed with the assistance of total intravenous anesthesia and ECMO intraoperative pulmonary protective ventilation. The patient received postoperative ICU supportive care. After surgical treatment, the patient was successfully withdrawn from ECMO on postoperative Day 1. The tracheal tube was removed on postoperative Day 4, and she was discharged from the hospital on postoperative Day 15. CONCLUSION: The multi-disciplinary treatment provided maximum medical optimization for surgical anesthesia and veno-venous ECMO which provided adequate protection for the patient's perioperative treatment.

6.
World J Clin Cases ; 10(34): 12543-12550, 2022 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-36579088

RESUMO

BACKGROUND: As shown in the statistics from the World Health Organization, it is estimated that approximately 75000 new cases of cervical cancer occur every year in China. In 2008, 33000 people died of cervical cancer in China. It is proven that most women are at risk of cervical cancer. The progression from human papillomavirus (HPV) infection to cervical cancer can be several years or decades, which offers a unique opportunity to prevent cancer. AIM: To observe the changes in ThinPrep cytology tests (TCT) and HPV infection in patients who were detected to be positive via TCT screening of cervical cancer and further explore the biopsy results. METHODS: This paper performed a follow-up study on 206 cervical cancer screening-positive patients of 12231 total cases from our previous research. We conducted an observational study on the TCT results based on the interpretation of The Bethesda System. RESULTS: Over a 5-year period, 10 cases received consistent follow-up. The proportions of cases in which glandular epithelial lesions were detected increased over the follow-up period. The differences between the years were statistically significant (P < 0.01). Over the 5 years, the proportion of patients whose squamous epithelial lesions transformed into glandular epithelial lesions increased yearly. Annual positive rates of HPV infection were: year 1, 73% (24/33); year 2, 43% (6/14); year 3, 36% (9/25); year 4, 50% (9/18); and year 5, 25% (6/24). The positive detection rate after biopsy over a 9-year period was 29%. CONCLUSION: The follow-up study for 5 years to 9 years revealed a tendency to change from squamous epithelial lesions to glandular epithelial lesions and an improvement of the disease (which had not been reported previously). The HPV test indicated a high negative conversion ratio of the viral infection. However, the follow-up cases were not found to have persistent infection of high-risk HPV. Therefore, early intervention of cervical cancer screening is necessary. Low re-examination compliance, patient education, and preventive measures should be enhanced.

7.
J Sep Sci ; 32(17): 2919-27, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19662640

RESUMO

A novel approach for differentiation and dating of red ink entries of seals on documents was developed based on ion-pairing HPLC (IP-HPLC) and GC/MS. Sixty-nine red ink pastes of seals were collected and the chromatographic conditions for separation of the dye components by IP-HPLC and the volatile additives by GC/MS in the ink entries were optimized. According to the dye components and additives, the ink entries were classified by HPLC with a multi-wavelength UV detector. The volatile components of the inks were identified by GC/MS and the classification of the ink entries was also investigated based on these volatile additives. The results showed that most of the ink entries of the seals can be differentiated by combining HPLC with a multi-wavelength detector and GC/MS methods. The degradation of the standard dye mixtures and the compositional changes of the ink entries of seals were investigated in light or natural aging conditions. The results indicated that the dye components decomposed in light or natural storage conditions, while the rates of the degradation depended on the structures of the dye components, the aging conditions, even the additives of the ink pastes. The results also showed that there existed good relationships between the compositional changes of the ink entries and the aging time, which can provide scientific evidences and valuable clues for dating of the ink entries.

8.
J AOAC Int ; 91(1): 252-7, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18376605

RESUMO

A novel method for simultaneous determination of 8 sulfonamide residues (sulfathiazole, sulfapyridine, sulfadiazine, sulfamerazine, sulfamonome-thoxine, sulfachloropyridazine, sulfamethoxazole, and sulfadimethoxine) in honey samples by high-performance liquid chromatography (HPLC) has been developed on the basis of precolumn derivatization with 9-fluorenylmethyl-chloroformate (FMOC-Cl). Sulfonamide residues in honey samples were extracted and purified by matrix solid-phase dispersion with C18 as the solid support. The residues were derivatized by FMOC-CI, and the FMOC-sulfonamide derivatives were further purified by solid-phase extraction with silica gel as the solid support prior to HPLC analysis. The average recoveries for most sulfonamide compounds at different spiking levels (from 10 to 250 microg/kg) were > 70% with relative standard deviations < 16%, and their limits of detection were 4.0 microg/kg. The established analytical method has high sensitivity and repeatability and can be applicable for determining the sulfonamide residues in various honey matrixes.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Resíduos de Drogas/análise , Mel/análise , Sulfonamidas/análise
9.
Mayo Clin Proc ; 91(4): 456-68, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27046523

RESUMO

OBJECTIVE: To evaluate the efficacy and safety of lubiprostone in the treatment of chronic idiopathic constipation (CIC) and irritable bowel syndrome with constipation (IBS-C). PATIENTS AND METHODS: We performed a literature search of the MEDLINE, Cochrane, Google Scholar, and ClinicalTrials.gov databases (from January 1, 2005, through January 31, 2015). Relevant studies meeting the inclusion criteria were manually searched by 2 independent reviewers. Efficacy outcomes evaluated at 1 week, 1 month, and 3 months of intervention were weekly frequency of spontaneous bowel movements, severity of constipation, consistency of stools, degree of abdominal pain/discomfort, degree of straining, and abdominal bloating. RESULTS: Of 246 studies identified, data from 9 trials comprising 1468 patients (63.6%) in the lubiprostone group and 841 (36.4%) in the placebo group were analyzed. We found that lubiprostone treatment significantly improved the severity of constipation, stool consistency, abdominal pain, degree of straining, and abdominal bloating at 1 week (P≤.03) and 1 month (P≤.004), except for abdominal pain at 1 month, which was similar to that when treated with placebo (P=.21). At 3 months, except for abdominal bloating (P=.03), there was no difference between lubiprostone and placebo groups in all other outcomes (P≥.05). Adverse effects such as nausea, vomiting, and diarrhea were common (incidence rate, 2.4%-75%); however, the incidence of serious adverse effects was low (<5%) and was mostly unrelated to lubiprostone treatment. CONCLUSION: Lubiprostone is a safe and efficacious drug for the treatment of chronic idiopathic constipation and irritable bowel syndrome with constipation, with limited adverse effects in 3 months of follow-up.


Assuntos
Dor Abdominal/tratamento farmacológico , Doença Crônica/tratamento farmacológico , Constipação Intestinal/tratamento farmacológico , Fármacos Gastrointestinais/uso terapêutico , Síndrome do Intestino Irritável/tratamento farmacológico , Laxantes/uso terapêutico , Lubiprostona/uso terapêutico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ensaios Clínicos Controlados Aleatórios como Assunto , Adulto Jovem
10.
Forensic Sci Int ; 236: 99-108, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24529780

RESUMO

The establishment of approaches for the differentiation of the ink entries of seals on paper can provide evidence to authenticate the related documents and can play a key role in judicial expertise. The identification and discrimination method for 38 red ink entries of seals on paper has been investigated using laser desorption ionization mass spectrometry (LDI-MS). Six dye components for the ink pastes of seals, Scarlet powder (SP), Bronze Red C (BR), Fast Red R (FR), Basic Violet 3 (BV3), Pigment Red 22 (PR22) and Pigment Red 112 (PR112), have been identified by their LDI-MS spectra, and the results have been confirmed by electrospray ionization quadruple-time of flight mass spectrometry (QTOF-ESI-MS/MS) and inductively coupled plasma atomic emission spectrometry (ICP-AES). The 38 ink entries were classified into six groups based on the presence or the absence of the pigments in their positive and negative LDI-MS spectra, and the discrimination power (DP) was calculated to be about 82%. The ink entries within each group were further differentiated from the relative peak areas (RPA) of the fragments for the pigments and the profile of their LDI-MS spectra, and thus the DP was increased to 98%. All the 38 ink entries could be discriminated (the DP was 100%), if including the contribution of unknown peaks. Compared with the results obtained by the FTIR and Raman methods, the established LDI-MS approach could provide more information of the dye components in the ink entries. The results showed that the developed LDI-MS method is powerful, sensitive and rapid and can directly differentiate the red ink entries of seals from paper substrates, thus offering a novel approach to judge the authenticity of documents.

11.
Ying Yong Sheng Tai Xue Bao ; 24(11): 3185-91, 2013 Nov.
Artigo em Zh | MEDLINE | ID: mdl-24564148

RESUMO

Taking the Qihe County in Shandong Province of East China as the study area, soil samples were collected from the field, and based on the hyperspectral reflectance measurement of the soil samples and the transformation with the first deviation, the spectra were denoised and compressed by discrete wavelet transform (DWT), the variables for the soil alkali hydrolysable nitrogen quantitative estimation models were selected by genetic algorithms (GA), and the estimation models for the soil alkali hydrolysable nitrogen content were built by using partial least squares (PLS) regression. The discrete wavelet transform and genetic algorithm in combining with partial least squares (DWT-GA-PLS) could not only compress the spectrum variables and reduce the model variables, but also improve the quantitative estimation accuracy of soil alkali hydrolysable nitrogen content. Based on the 1-2 levels low frequency coefficients of discrete wavelet transform, and under the condition of large scale decrement of spectrum variables, the calibration models could achieve the higher or the same prediction accuracy as the soil full spectra. The model based on the second level low frequency coefficients had the highest precision, with the model predicting R2 being 0.85, the RMSE being 8.11 mg x kg(-1), and RPD being 2.53, indicating the effectiveness of DWT-GA-PLS method in estimating soil alkali hydrolysable nitrogen content.


Assuntos
Algoritmos , Nitrogênio/análise , Solo/química , Análise Espectral/métodos , Álcalis/química , China , Monitoramento Ambiental/métodos , Hidrólise , Análise dos Mínimos Quadrados , Modelos Teóricos , Análise de Ondaletas
12.
Artigo em Inglês | MEDLINE | ID: mdl-22925974

RESUMO

Determination of the red ink entries of seals on documents can provide valuable evidences for solving related crimes, distinguishing the truth of artworks, and so establishment of nondestructive approaches would play a key role in forensic analysis and related aspects. Raman and FT-IR spectroscopy have been applied for analyzing 105 kinds of red ink entries on documents. The dye components of the ink entries were identified by FT-Raman and confocal Raman microspectroscopy, and then the ink entries were classified into four groups based on these dye components. The ink entries were further discriminated by their FT-IR spectra according to adsorption peaks of the main components, the relative intensities of the characteristic bands and the profiles of the spectra. The results showed that 70 ink entries out of 105 have been individually identified and the remaining 35 ink entries can be divided into 13 subclasses. Combination of Raman and FT-IR spectroscopic methods can provide a powerful nondestructive discriminating tool for identification of the red ink entries of seals on papers. These approaches would have potential application in archeology, art and forensic science.


Assuntos
Tinta , Papel , Análise Espectral Raman , Cor , Corantes/química , Espectroscopia de Infravermelho com Transformada de Fourier
13.
J Chromatogr A ; 1220: 7-13, 2012 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-22197256

RESUMO

Surface molecular imprinted polymers (MIPs) on silica gel particles for highly selective recognition of tetrabromobisphenol A (TBBPA) were prepared by a sol-gel process. Diphenolic Acid (DPA) and bisphenol A (BPA), whose structures were similar to that of TBBPA were selected as dummy template molecules, and 3-aminopropyltriethoxysilane (APTES) and tetramethoxysilane (TEOS) were chosen as functional monomer and cross-linker, respectively. The obtained materials were characterized by FT-IR with diffuse reflectance accessory and the results indicated polymers were successfully grafted on the surface of silica gel supporters. The maximum static adsorption capacities for TBBPA of the DPA-MIPs, BPA-MIPs and non-imprinted polymers (NIPs) were 45, 38 and 22 mg g(-1) respectively, and the results of dynamic adsorption showed that the adsorption equilibrium can be achieved within 15 min for DPA- and BPA-MIPs. Both the DPA- and BPA-MIPs have higher selectivity for TBBPA than that of NIP when they are used as the sorbents for the solid phase extraction (SPE), while the adsorption property of DPA-MIPs was superior to that of BPA-MIPs at low concentration levels of TBBPA. The results indicated DPA-MIPs had more high affinity binding sites for TBBPA, which demonstrated that the strong interactions between the template and the functional monomer were favorable to form high affinity binding sites and improve the selectivity of the polymers. A corresponding analytical method for determination of the TBBPA residues in environmental samples was developed. The recoveries of TBBPA in tap water, river water and lake water were in the range from 85% to 97% with relative standard deviations below 7%, and its limit of detection can reach 2 ng mL(-1).


Assuntos
Impressão Molecular/métodos , Bifenil Polibromatos/isolamento & purificação , Dióxido de Silício/química , Extração em Fase Sólida/métodos , Poluentes Químicos da Água/isolamento & purificação , Água/química , Adsorção , Cromatografia Líquida , Água Doce/química , Fenóis/química , Bifenil Polibromatos/análise , Bifenil Polibromatos/química , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/química
14.
J Agric Food Chem ; 60(42): 10472-9, 2012 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-23045957

RESUMO

Molecularly imprinted film with diphenolic acid (DPA) as dummy template molecule has been grafted on the surface of Mn-doped ZnS quantum dots (QDs) to develop a selective and sensitive sensor for rapid determination of tetrabromobisphenol A (TBBPA) in water and soils. The obtained DPA-MIP-QDs sensor has distinguished selectivity and high binding affinity to TBBPA. The fluorescence quenching fractions of the sensor presented a satisfactory linearity with the concentrations of TBBPA in the range of 0.1-100 µM, and its limit of detection can reach 0.015 µM. The sensor has been successfully applied to determine the TBBPA in water and soil samples, and the average recoveries of the TBBPA at various spiking levels ranged from 80.2% to 96.5% with relative standard deviation below 8.0%. The results provided a clue to develop sensors for rapid determination of hazardous materials from complex matrixes.


Assuntos
Impressão Molecular , Bifenil Polibromatos/análise , Pontos Quânticos , Poluentes do Solo/análise , Poluentes Químicos da Água/análise , Limite de Detecção , Luminescência , Espectrometria de Fluorescência
15.
J Chromatogr A ; 1218(22): 3521-8, 2011 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-21497820

RESUMO

A novel approach for identification and determination of emulsion explosives with Span-80 (sorbitol mono-oleate) as the emulsifier and their postblast residues by gas chromatography-mass spectrometry (GC-MS) has been developed. 24 kinds of emulsion explosives collected have been processed by transesterification reaction with metholic KOH solution and the emulsifier has turned into methyl esters of fatty acids. From the peak area ratios of their methyl esters, most of these emulsion explosives can be differentiated. In order to detect the postblast residues of emulsion explosives, the sorbitols in the emulsifier Span-80 obtained after transesterification reaction have been further derivatized by silylation reaction with N,O-bis-(trimethylsilyl)trifluoroacetamide (BSTFA) containing 1% trimethylchlorosilane (TMCS) as the derivatizing reagent. The derivatization conditions were optimized and the derivatives were determined by GC-MS. The results showed that the silylation derivatives of sorbitol and it isomers, combined with hydrocarbon compounds and methyl esters of fatty acids, were the characteristic components for identification of the emulsion explosives. The established approach was applied to analyze the postblast residues of emulsion explosives. It has been found that the method was sensitive and specific, especially when detecting the derivatives of sorbitol and its isomers by GC-MS in selecting ion mode. The information of the characteristic components can help probe the origin of the emulsion explosives and providing scientific evidences and clues for solving the crimes of the emulsion explosive explosion.


Assuntos
Emulsificantes/análise , Substâncias Explosivas/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Hexoses/análise , Emulsificantes/química , Hexoses/química , Reprodutibilidade dos Testes , Poluentes do Solo/análise , Poluentes do Solo/química , Sorbitol/análise , Sorbitol/química
16.
Forensic Sci Int ; 180(1): 43-9, 2008 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-18703295

RESUMO

A novel approach for the identification and dating of the fountain pen ink entries on paper has been established by ion-pairing high-performance liquid chromatography (IP-HPLC). Twelve black and six red fountain inks have been collected, and their ink entries have been prepared by drawing lines on paper. The chromatographic conditions for separation of their dye components after extraction with solvents were optimized. Under the optimized conditions, the 18 fountain pen inks were differentiated individually by comparing the number of detectable main or minor dye components, and the relative peak intensities of each component. The ink entries were artificially and naturally aged, and the analysis results showed that the ink dye components were significantly decomposed when exposed to UV or fluorescent light compare to those of inks stored under natural condition. The changes of the relative peak height for the dye components were linearly related to the aging time, especially under natural aging conditions. The degradation characteristics of the dye components under different aging conditions provide scientific evidences for dating of the suspicious fountain pen ink entries on document.

17.
Mol Plant ; 1(5): 720-31, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19825576

RESUMO

Heterosis, or hybrid vigor, refers to the phenomenon in which hybrid progeny of two inbred varieties exhibits enhanced growth or agronomic performance. Although a century-long history of research has generated several hypotheses regarding the genetic basis of heterosis, the molecular mechanisms underlying heterosis and heterotic gene expression remain elusive. Here, we report a genome-wide gene expression analysis of two heterotic crosses in rice, taking advantage of its fully sequenced genomes. Approximately 7-9% of the genes were differentially expressed in the seedling shoots from two sets of heterotic crosses, including many transcription factor genes, and exhibited multiple modes of gene action. Comparison of the putative promoter regions of the ortholog genes between inbred parents revealed extensive sequence variation, particularly small insertions/deletions (INDELs), many of which result in the formation/disruption of putative cis-regulatory elements. Together, these results suggest that a combinatorial interplay between expression of transcription factors and polymorphic promoter cis-regulatory elements in the hybrids is one plausible molecular mechanism underlying heterotic gene action and thus heterosis in rice.


Assuntos
Perfilação da Expressão Gênica , Genoma de Planta/genética , Vigor Híbrido/genética , Hibridização Genética , Mutação INDEL/genética , Oryza/genética , Regiões Promotoras Genéticas/genética , Sequência de Bases , Cruzamentos Genéticos , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Redes e Vias Metabólicas/genética , Modelos Genéticos , Dados de Sequência Molecular , Oryza/metabolismo , Polimorfismo Genético
18.
Mol Plant ; 1(5): 816-29, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19825584

RESUMO

It has been reported that rice chromosome 4 has eight major heterochromatic knobs within the heterochromatic half and that this organization correlates with chromosomal-level transcriptional activity. To better understand this chromosomal organization, we created a model based on the statistical distribution of various types of gene models to divide chromosome 4 into 17 euchromatic and heterochromatic regions that correspond with the cytological staining. Fluorescence in-situ hybridization (FISH) experiments using a set of bacterial artificial chromosome (BAC) clones from chromosome 4 placed all 18 clones in the region predicted by the model. Elevated levels of H3K4 di- and tri-methylation detected by chromatin-immunoprecipitation (ChIP) on chip were correlated with euchromatic regions whereas lower levels of these two modifications were detected in heterochromatic regions. Small RNAs were more abundant in the heterochromatic regions. To validate these findings, H3K4 trimethylation, H3K9 acetylation, H4K12 acetylation, and H3K9 di- and tri-methylation of 19 individual genes were measured by ChIP-PCR. Genes in heterochromatic regions had elevated H3K9 di- and tri-methylation while genes in euchromatic regions had elevated levels of the other three modifications. We also assayed cytosine methylation of these genes using the restriction enzymes McrBC, HapII, and Msp I. This analysis indicated that cytosines of transposable elements and some genes located in heterochromatic regions were methylated while cytosines of the other genes were unmethylated. These results suggest that local transcriptional activity may reflect the organization of the corresponding part of the chromosome. They also indicate that epigenetic regulation plays an important role in correlating chromosomal organization with transcriptional activity.


Assuntos
Cromossomos de Plantas/genética , Epigênese Genética/genética , Oryza/citologia , Oryza/genética , Sequência de Bases , Cromossomos Artificiais Bacterianos/genética , Metilação de DNA/genética , Elementos de DNA Transponíveis/genética , Eucromatina/genética , Genes de Plantas , Loci Gênicos/genética , Heterocromatina/genética , Histonas/metabolismo , Hibridização in Situ Fluorescente , Análise de Sequência com Séries de Oligonucleotídeos , Processamento de Proteína Pós-Traducional , RNA de Plantas/metabolismo , Transcrição Gênica
19.
J Sep Sci ; 30(16): 2647-55, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17868178

RESUMO

A novel approach for simultaneous determination of 12 sulphonamides (sulphadiazine, sulphamethazine, sulphathiazole, sulphadimethoxine, sulphamerazine, sulphapyridine, sulphamethoxazole, suphamethizole, sulphaquinoxaline, sulphameter, sulphamonomethoxine, and sulphachloropyridazine) in animal tissues (swine muscle and liver, chicken muscle, beef muscle) by HPLC with UV detection has been developed. A pre-column derivatization of the sulphonamide compounds with 9-fluorenylmethyl chloroformate (FMOC-Cl) has been proposed and the reaction conditions have been optimized. The FMOC-sulphonamide derivatives were purified by SPE with silica gel as solid support prior to HPLC separation. The limits of detection for the sulphonamide compounds were greatly improved after the derivatization and purification step for the derivatives. Sulphonamide residues in animal tissues were extracted by acetonitrile and purified by solid phase extraction with C(18) as the solid support. The method developed has high sensitivity and good repeatability, and the average recoveries for most of the sulphonamides at various spiking levels were above 70% with relative standard deviations below 13.7%. The limits of detection for most sulphonamides can reach 3-5 microg/kg.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Resíduos de Drogas/análise , Fluorenos/química , Sulfonamidas/análise , Animais , Concentração de Íons de Hidrogênio , Cinética , Sensibilidade e Especificidade , Espectrofotometria Ultravioleta , Temperatura
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