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OBJECTIVE: An analytical method was developed for tetrodotoxin(TTX) in urine by liquid chromatography-tandem mass spectrometry(LC-MS/MS) with internal standard calibration. METHODS: TTX in the sample was extracted with the mixture of acetic acid/methanol/acetonitrile(0.005 mL/0.8 mL/1.8 mL), cleaned by solid phase extraction(SPE) with cation exchange cartridge, eluted with 50% acetonitrile/water containing 0.3% hydrochloric acid, and neutralized with ammonia. The extract was separated by a Waters XBridge~(TM) BEH Amide column(150 mm×3.0mm, 1.7 µm) and measured by MS/MS. By optimizing sample extraction and SPE cleanup conditions, the problems of low recovery and strong suppression effects of MS signal for TTX in urine were resolved when cleaned with cation exchange cartridge. RESULTS: Quantitatively calibrated by the internal standard of Kasugamycin, good linear relationship was found for TTX in urine at the range of 0.2-200 µg/L with the correlation coefficient(r~2) of 0.997. The limits of detection and quantitation for TTX in sample matrix were 0.1 and 0.2µg/L, respectively. The average recoveries at three spiking levels(0.2, 10.0 and 200 µg/L) were 89.3%-95.3% with relative standard deviation(n=6) less than 5.1%. The concentrations of TTX in urine from 11 poisoning patients were 0.4-138 µg/L. The detection rate was 100% in urine collected within 3 days after poisoning. CONCLUSION: The established method was simple, accurate and sensitive. It can provide reliable technical support for the rapid treatment of TTX poisoning events and the study of toxin metabolism in vivo.
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Espectrometria de Massas em Tandem , Humanos , Tetrodotoxina , Cromatografia Líquida , Calibragem , Acetonitrilas , CátionsRESUMO
BACKGROUND: Fatty acid synthase (FASN) is a lipogenic enzyme that participates in tumor progression. We previously showed that FASN is dysregulated in OS malignancy, but the molecular mechanism(s) of these effects remained unclear. METHODS: We examined differentially expressed proteins (DEPs) in FASN-silenced osteosarcoma 143B cells and their parental cells by isobaric tags for relative and absolute quantitation (iTRAQ). Differentially expressed proteins were classified using GO and KEGG analysis. The association between FASN and heterogeneous nuclear ribonucleoprotein A1 (HNRNPA1) was confirmed using qPCR, Western blot, and immunohistochemistry. The function of HNRNPA1 in osteosarcoma was determined using CCK-8, colony formation, wound healing, transwell migration, and invasion assays. RESULTS: Among the 4971 identified proteins, 567 DEPs (325 upregulated and 242 downregulated) were identified. The top 10 upregulated proteins comprised HIST1H2AB, INA, INTS5, MTCH2, EIF1, MAPK1IP1L, PXK, RPS27, PM20D2, and ZNF800, while the top 10 downregulated proteins comprised NDRG1, CNTLN, STON2, GDF7, HECTD3, HBB, TPM1, PPP4R4, PTTG1IP, and PLCB3. Bioinformatic analysis indicated that the DEPs were related to cellular processes, metabolic processes, biological regulation, binding, and catalytic activity. HNRNPA1 was dysregulated in FASN-silenced 143B and HOS cells. qPCR, Western blot, and immunohistochemistry showed that FASN expression positively correlates with HNRNPA1 expression. Further studies indicated that HNRNPA1 correlates with OS diagnosis and prognosis. And HNRNPA1 silence inhibits the proliferation, migration, and invasion in OS cells. CONCLUSION: HNRNPA1 acts as targets downstream of FASN and potential biomarker and oncogene in OS.
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Neoplasias Ósseas/metabolismo , Ácido Graxo Sintase Tipo I/metabolismo , Osteossarcoma/metabolismo , Proteômica/métodos , Adulto , Neoplasias Ósseas/genética , Neoplasias Ósseas/patologia , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Ácido Graxo Sintase Tipo I/genética , Feminino , Ontologia Genética , Ribonucleoproteína Nuclear Heterogênea A1/genética , Ribonucleoproteína Nuclear Heterogênea A1/metabolismo , Humanos , Masculino , Osteossarcoma/genética , Osteossarcoma/patologia , Adulto JovemRESUMO
OBJECTIVE: To analyze the contents of fat-soluble vitamins in different kinds of eggs and egg products in Hangzhou City. METHODS: The contents of fat-soluble vitamin A, vitamin E, vitamin K_1 and vitamin K_2(menaquinone-4, menaquinone-7 and menaquinone-9) in eggs and egg products were determined by the high-performance liquid chromatography method. The contents of vitamin D were determined by high performance liquid chromatography-tandem mass spectrometry. The determined contents were compared with the corresponding nutrient reference values. RESULTS: The contents of vitamin A, vitamin D, vitamin E and vitamin K in different eggs and egg products were 64-278 µg RAE/100 g edible, 0. 2-9. 6 µg/100 g edible, 0. 59-2. 31 mg α-TE/100 g edible and 9. 5-84. 8 µg/100 g edible, respectively, accounting for 4%-192% of the corresponding nutrient reference values. The contents of fat-soluble vitamin A, vitamin D, vitamin E and vitamin K in duck, goose and quail eggs were higher than those in chicken eggs and pigeon eggs. CONCLUSION: There are some differences in fat-soluble vitamin A, vitamin D, vitamin E and vitamin K in different eggs and egg products, but there is no significant difference between groups.
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Ovos , Vitaminas , Animais , Cromatografia Líquida de Alta Pressão , Ovos/análise , Vitamina A/análise , Vitamina D , Vitaminas/análiseRESUMO
OBJECTIVE: Comparison and analysis of α-, ß-, γ-, δ-tocopherol(T) and α-, ß-, γ-, δ-tocotrienol(T3) in 44 species of seafood and aquatic products is under processed to enrich the database of food composition in China and provide a scientific reference for dietary intake choice. METHODS: Quantitative and correlation analysis of eight vitamin E isomers were based on external calibration method with reversed-phase high-performance liquid chromatography-fluorescence detector, after hot saponification with alkaline and liquid-liquid extraction. RESULTS: The content of α-tocopherol equivalent(α-TE) in seafood and aquatic products varied greatly(from 0. 10 to 4. 01 mg/100 g edible), as well as the isomer forms. Aspect of vitamin E forms in aquatic fish, detection rates of α-T and α-T3 were both 100%, while the rates of γ-T and γ-T3 were 31. 58% and 68. 42%, respectively. Aspect of vitamin E forms in sea fish, detection rates α-T3, γ-T and γ-T3 were 28. 57%, 28. 57% and 35. 71%, respectively, while the rate of α-T was 100%. The form of vitamin E isomers in fish was at some extent different when they raise up in wild and farming environment, whereas there was no significant different in content of isomers. For shrimp and crabs, the content of α-TE was also various(from 0. 31 to 14. 27 mg/100 g edible), whereas α-T was the primary vitamin E form. And the content of α-T in female crabs was a little higher than that in male crabs, without statistic difference. With respect to correlation analysis, there was a strong correlation between γ-T and α-T3 in sea fish, while weak correlation of isomers in aquatic fish and certain correlations of isomers in shrimp and crab. CONCLUSION: The level of vitamin E content in seafood and aquatic products are quite different. Thus, it will bring in different effects on total activity and intake of vitamin E isomers by consumption of different species of seafood and aquatic products.
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Tocotrienóis , Vitamina E , Animais , China , Feminino , Masculino , Alimentos Marinhos , TocoferóisRESUMO
We established a method for the separation and detection of nine hydroxylated polychlorinated biphenyls in whole blood and urine samples using ultra high performance liquid chromatography coupled with electrospray negative ionization tandem mass spectrometry. Clean-up procedures involved a filtration step, and optimization involved a pretreatment step consisting of a simple liquid-liquid extraction using hydrated silica-gel chromatography (5%). Nine hydroxylated polychlorinated biphenyls were separated on an ultra high performance liquid chromatography HSS T3 column using a gradient elution program of 2 mmol ammonium formate aqueous solution (A) and methanol (B). Recovery ranged from 84.0 to 105.4% for the nine different hydroxylated polychlorinated biphenyls in urine with three spiked levels of 0.1, 1, and 2 ng and from 73.5 to 98.6% for the blood with spiked levels of 0.2, 1, and 2 ng. The relative standard deviations were <8.7% (n = 6), and the limits of detection in urine and whole blood for the nine hydroxylated polychlorinated biphenyls were in the range of 1.5-4 and 20-100 pg/g, respectively. This analytical method may enable the simultaneous detection of various hydroxylated polychlorinated biphenyls from complex tissue matrices.
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Cromatografia Líquida de Alta Pressão , Bifenilos Policlorados/sangue , Bifenilos Policlorados/urina , Espectrometria de Massas em Tandem , Animais , Isótopos de Carbono , Hidroxilação , Masculino , Bifenilos Policlorados/química , Ratos , Ratos Sprague-DawleyRESUMO
OBJECTIVE: To develop a method for simultaneous determination of 5 nitroimidazole antibiotics and 17 sulfonamides antibiotics in disinfection products by ultra-performance liquid chromatography tandem mass spectrometry(UPLC-MS/MS). METHODS: Samples were spiked with isotope internal standard, and then extracted by 2% formic acid solution and acetonitrile with ultrasonic, followed by MCX column to remove matrix interference and for enrichment. The supernatants were diluted with 2% formic acid solution before loading on the columns, then washed with 2% formic acid solution and methanol respectively, eluted with 5% ammonium methanol. The separation was performed on a CORTECS~(TM) UPLC C_(18)(100 mm×2. 1 mm, 1. 6 µm) column by using 0. 1% formic acid solution and 0. 1% formic acid acetonitrile as mobile phase with gradient elution. The antibiotics were analyzed by UPLC-MS/MS. RESULTS: The linear ranges of 22 antibiotics were 0. 05-5. 0 ng/mL and the correlation coefficients were greater than 0. 999. The limits of detection(LODs) were 0. 03-0. 15 µg/kg and the recoveries were 84. 3%-121. 2% with the relative standard deviations were 1. 13%-8. 43%(n=6). The method was successfully used to detect the content of antibiotics in 20 disinfection products, 45% of samples had been detected positively. CONCLUSION: This method is simple, sensitive, selective and accurate, and could be applied for simultaneous detection of antibiotics in disinfection products.
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Antibacterianos , Espectrometria de Massas em Tandem , Antibacterianos/análise , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , DesinfecçãoRESUMO
GINS2 is overexpressed in several cancers, but little is known about its role in osteosarcoma (OS). A series of in vivo and in vitro experiments were conducted to explore the role of GINS2 in OS. In this study, we demonstrated that GINS2 was found to be highly expressed in OS tissues and cell lines, which was associated with poor outcomes in OS patients. GINS2 knockdown hindered the growth and induced apoptosis in OS cell lines in vitro. Furthermore, GINS2 knockdown effectively inhibited the growth of a xenograft tumor in vivo. By using an Affymetrix gene chip and intelligent pathway analysis, it was demonstrated that the GINS2 knockdown could reduce the expression of several targeted genes and reduce the activity of the MYC signaling pathway. Mechanically, LC-MS, CoIP, and rescue experiments revealed that GINS2 promoted tumor progression through the STAT3/MYC axis in the OS. Moreover, GINS2 was associated with tumor immunity and may be a potential immunotherapeutic target for OS.
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STUDY DESIGN: A hospital-based retrospective epidemiological study. OBJECTIVE: To describe the recent epidemiological profile and characteristics of traumatic cervical spinal cord injury (TCSCI) in Nanchang, Jiangxi Province, China. SETTING: The First Affiliated Hospital of Nanchang University, The Second Affiliated Hospital of Nanchang University and The Third Affiliated Hospital of Nanchang University. METHODS: We retrieved the medical records of 1290 persons with TCSCI admitted to The First Affiliated Hospital of Nanchang University, The Second Affiliated Hospital of Nanchang University and The Third Affiliated Hospital of Nanchang University between January 2012 and December 2018. The characteristics recorded were age, sex, aetiology of the injury, neurological level, American Spinal Injury Association (ASIA) impairment scale, patient source, and associated trauma. Categorical data were reported as frequency and proportions and compared using the Fisher's exact or Chi-square test. P < 0.05 was considered to be statistically significant. RESULTS: A total of 1290 persons with TCSCI were included in the present study. The largest age group was 46-60 years, accounting for 31.6% of the patients; the mean age was 53.1 ± 16.2 years, and the male/female ratio was 7.06:1. More than 87.4% of persons were transferred from a primary or secondary hospital. The leading cause of injury was motor vehicle collision (41.3%), followed by low fall (26.5%). The most common cervical spine injury level was the C5 segment, accounting for 24.3% of cases. As for severity, ASIA grade D was encountered most frequently, with a total of 518 persons (40.2%). Among all participants, 56.8% had associated trauma, the most common being head injuries (18.2%). Surgery was the major treatment choice (51.2%), and the number of patients undergoing surgery is increasing from 2012 to 2018, P = 0.02. CONCLUSION: Persons with TCSCI in Nanchang had specific epidemiological characteristics, and preventive measures should focus on middle-aged and older adults. In addition, more attention should be paid to balancing development of medical resources and technology between urban and rural areas.
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Medula Cervical , Lesões do Pescoço , Traumatismos da Medula Espinal , Traumatismos da Coluna Vertebral , Adulto , Idoso , China/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Lesões do Pescoço/complicações , Estudos Retrospectivos , Traumatismos da Medula Espinal/complicações , Traumatismos da Medula Espinal/etiologiaRESUMO
Liver, fat (adipose tissue), blood, and feces are common endpoints used to determine the bioavailability of persistent organic pollutants (POPs). However, it is not known whether the bioavailability of each endpoints is comparable or whether there is a comprehensive endpoint that can be used for all congeners for the measurement of bioavailability. In this study, we observed the accumulation and distribution of 10 polychlorinated dibenzo-p-dioxins/furans (PCDD/Fs) and 18 polychlorinated biphenyls (PCBs) in different organs of Sprague-Dawley (SD) rats and calculated the bioavailability based on feces, liver, and fat endpoints. Our results indicated that PCB 126, PCB 169, and 50% of PCDD/F congeners were mainly accumulated in the liver, with a bioavailability ranging from 28.9 to 50.6%. On the other hand, higher chlorinated (> 5 Cl) PCB congeners were mainly accumulated in adipose tissues, with a bioavailability ranging from 20.1 to 82.2%, while lower chlorinated (< 5 Cl) pollutants, such as 2,3,7,8-TeCDF, 2,3,7,8-TeCDD, 1,2,3,7,8-PeCDF, and PCB 28, 52, 77, 81, were likely metabolized over 36% in rats during the 8-week experimental period. If we considered metabolization (degradation) as a type of bioavailable process, then the fecal endpoint was a feasible option. However, if we considered the selective accumulation behavior of some congeners in different organs/tissues, then there was no single comprehensive endpoint suitable for all congeners. Lastly, female rats showed significantly higher PCDD bioavailability than male rats at low dose level (0.2 ng/100 g b.w./d); however, the difference in PCB bioavailability between female and male rats was not significant.
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Bifenilos Policlorados , Dibenzodioxinas Policloradas , Feminino , Masculino , Ratos , Animais , Ratos Sprague-Dawley , Dibenzofuranos , Furanos , Disponibilidade BiológicaRESUMO
A municipal waste incinerator (MWI) in Zhejiang, China, operating since 2008 was completely reconstructed from 2016 to 2019. In 2013, we conducted a cross-sectional study of breastfeeding mothers living near the MWI. We evaluated the concentrations of polychlorinated biphenyls (PCBs) and polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in the mothers' breast milk and their infants' estimated daily intake (EDI). To investigate the temporal variations of these pollutants, we conducted a cross-sectional study of 29 mothers in 2019. We assessed the levels of 18 PCB congeners, 17 PCDD/F congeners, and 21 per- and polyfluoroalkyl substance (PFAS) congeners in breast milk and estimated the EDI. The mean total concentrations of PCDD/Fs (ΣPCDD/Fs) and PCBs (ΣPCBs) were 81.2 and 4.90 ng/g lipid, respectively, while the toxic equivalent quantity (TEQ) levels of ΣPCDD/Fs and dioxin-like PCBs (ΣDL-PCBs) were 2.7 and 1.4 pg WHO-TEQ/g lipid, respectively. Compared to our 2013 measurements, the mass concentrations of ΣPCDD/Fs and ΣPCBs decreased by 13% and 35%, respectively (3.361 vs. 2.915 pg/g wet weight [ww] and 269.1 vs. 175.0 pg/g ww, respectively). The TEQ-ΣPCDD/F levels decreased by 67% (0.241 vs. 0.080 pg/g ww), but the TEQ-ΣDL-PCB levels increased by 11% (0.046 vs. 0.051 pg WHO-TEQ/g ww). The median concentration of PFASs was 0.250 ng/mL, ranging from 0.151 to 0.833 ng/mL. The infants' mean EDI of total PCDD/Fs and DL-PCBs was 17.7 pg TEQ/kg body weight [bw], representing a 20% decline compared to 2013. The average EDI levels of PFOS, PFOA, and PFNA were 5.8, 17.9, and 1.7 ng/kg bw, respectively. A comprehensive comparison of the results with studies from around the world showed that the potential health risks posed by legacy PCDD/F and PCB pollutants were not as grave for mothers and infants living near this MWI, but the emerging PFAS pollutants represented a new cause for concern. MAIN FINDINGS: The potential health risks posed by legacy PCDD/F and PCB pollutants were not particularly serious for mothers and infants living near the MWI, but the emerging PFAS pollutants raised new concerns.
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Dioxinas , Poluentes Ambientais , Fluorocarbonos , Bifenilos Policlorados , Dibenzodioxinas Policloradas , Lactente , Feminino , Humanos , Dibenzodioxinas Policloradas/análise , Bifenilos Policlorados/análise , Dibenzofuranos , Dibenzofuranos Policlorados/análise , Aleitamento Materno , Dioxinas/análise , Estudos Transversais , Poluentes Ambientais/análise , Leite Humano/química , China , LipídeosRESUMO
The effects of curcumin on the bioavailability of polychlorinated dibenzo-p-dioxins/furans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (DL-PCBs) were investigated in Sprague-Dawley rats. Tetra- and penta-chlorinated PCDFs had the lowest bioavailability and hexa-chlorinated PCDD/Fs had the highest, while there was no obvious change in that of DL-PCBs. Curcumin markedly reduced the toxic equivalent (TEQ) of PCDD/Fs in rats, illustrating the potential to competitively inhibit absorption of PCDD/Fs by the epithelial cells of the small intestine due to the similar chemical structure (diphenyl) between curcumin and PCDD/Fs. Moreover, curcumin lowered the TEQ of DL-PCBs in the liver of male rats, but not female rats. The significant decrease in the bioavailability of PCDD/Fs and DL-PCBs demonstrates the potential detoxification mechanisms of curcumin.
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Curcumina/administração & dosagem , Dibenzofuranos Policlorados/farmacocinética , Poluentes Ambientais/farmacocinética , Absorção Intestinal/efeitos dos fármacos , Dibenzodioxinas Policloradas/farmacocinética , Administração Oral , Animais , Disponibilidade Biológica , Dibenzofuranos Policlorados/administração & dosagem , Dibenzofuranos Policlorados/antagonistas & inibidores , Dibenzofuranos Policlorados/toxicidade , Poluentes Ambientais/administração & dosagem , Poluentes Ambientais/antagonistas & inibidores , Poluentes Ambientais/toxicidade , Feminino , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Intestino Delgado/efeitos dos fármacos , Intestino Delgado/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Modelos Animais , Dibenzodioxinas Policloradas/administração & dosagem , Dibenzodioxinas Policloradas/antagonistas & inibidores , Dibenzodioxinas Policloradas/toxicidade , Ratos , Fatores Sexuais , Distribuição Tecidual/efeitos dos fármacosRESUMO
An effective method has been developed for the simultaneous determination of four bisphenols (bisphenol A, S, F and B) in various foodstuffs. The contaminants were extracted by QuEChERS-based strategy and subjected to ion-exchange solid-phase extraction for further clean-up. The critical variables were screened by Plackett-Burman design and then optimized by central composite design. Under the optimized conditions, satisfactory accuracy (recoveries 76%-116%) and precision (RSDsâ¯<â¯12%) were achieved. The established method was then used to assess the contamination status of 379 real samples. Bisphenol A was demonstrated to be the predominant bisphenol with highest incidence (79.7%) and average concentration (14.3⯵g/kg). The positive rates (mean concentration) of bisphenol S, F and B were 37.7% (1.6⯵g/kg), 26.9% (1.4⯵g/kg) and 0.0% (not detected), respectively. Finally, the daily dietary intakes of ∑4bisphenolsfor adult residents were estimated (55.9-76.1â¯ng/kgâ¯bw/day) according to the contamination concentrations and the daily recommended intakes.
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Compostos Benzidrílicos/análise , Análise de Alimentos/métodos , Fenóis/análise , Sulfonas/análise , Compostos Benzidrílicos/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Exposição Dietética , Humanos , Limite de Detecção , Fenóis/isolamento & purificação , Extração em Fase Sólida , Sulfonas/isolamento & purificação , Espectrometria de Massas em TandemRESUMO
Objective@#To explore the effects of protein powder on the bioavailability of perfluoroalkyl substances (PFASs) in blood and kidneys of rats and renal function change.@*Methods@#Twenty-four rats of the SD strain were randomly divided into the negative control group, PFASs group and protein powder group, with 8 rats (half males and half females) in each group. PFASs included 13 perfluorocarboxylic acids (PFCAs) and 8 perfluorosulfonic acids (PFSAs), and the mixture was used as a test subject for intervention. The rats in the negative control group were given deionized water at doses of 20 mL/kg·bw, in the PFASs group were given 5 mL/kg·bw of PFASs mixtures and 15 mL/kg·bw of deionized water, and in the protein powder group were given 5 mL/kg·bw of PFASs mixtures and 15 mL/kg·bw of protein powder (0.258 g/mL). After intervention for 28 successive days, body weight and kidney mass were weighed, and the kidney volume index was calculated. Serum creatinine and blood urea nitrogen were detected by an automatic biochemical analyzer. The PFCAs, PFSAs and PFASs contents were quantified in blood and kidney using ultra-high performance liquid chromatography-electrospray tandem mass spectrometry, and the bioavailability was estimated.@*Results@#There was no significant differences in kidney mass, kidney volume index, serum creatinine and blood urea nitrogen among the negative control group, PFASs group and protein powder group (all P>0.05). The bioavailability of blood PFCAs, PFSAs and PFASs in the protein powder group was not significantly different from the PFASs group (all P>0.05). Compared with the PFASs group, the bioavailability of PFCAs, PFSAs and PFASs were significantly increased in kidneys of male rats in the protein powder group (all P<0.05), while were not significant different in those of female rats (all P>0.05).@*Conclusion@#Protein powder at the dose of this study can significantly improve the bioavailability of PFASs in kidneys of male rats, while there no obvious effects on the bioavailability of blood PFASs and renal function.
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In this paper, we generalize the widely used simultaneous block iterative reconstruction algorithm and show that it converges, at a linear rate, to a weighted least-squares and weighted minimum-norm reconstruction. Our theoretical result provides a much simpler proof of the convergence properties obtained by Jiang and Wang and covers a much more general class of algorithms. The frequency domain iterative reconstruction algorithm is then introduced as a special application of our theory.
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Algoritmos , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Armazenamento e Recuperação da Informação/métodos , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
Obtaining high quality ultrasound images at high frame rates has great medical importance, especially in applications in which tissue motion is significant (e.g., the beating heart). Dynamic focus and dynamic aperture can improve image quality significantly, and they have been implemented on the receive beam in state-of-the-art medical ultrasound systems. However, implementing dynamic focus and dynamic aperture on the transmit beam compromises frame rate. We introduce a novel sinc squared-argument transmit aperture that is obtained by coherently integrating the quadratic phase change over a continuum of focal points. Thus uniform sensitivity and uniform point spread function can be achieved over a very large depth without reducing the frame rate. Numerical simulations validate our theoretical analysis and demonstrate significant promises of the new technique.
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Desenho Assistido por Computador , Aumento da Imagem/instrumentação , Interpretação de Imagem Assistida por Computador/métodos , Transdutores , Ultrassonografia/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento , Aumento da Imagem/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Ultrassonografia/métodosRESUMO
Although the use of dedicated gamma cameras in scintimammography permits closer access to the breast and improved spatial resolution relative to conventional gamma cameras, the task of quantifying the radiotracer concentration in the lesion relative to that in the surrounding breast tissue remains challenging because of the lesion-depth-dependent effects of attenuation and collimator blur. We are developing a dual modality scanner that combines digital x-ray mammography and a dedicated gamma camera on a common upright gantry. Here we present the results of a phantom study evaluating the use of the dual modality system for quantifying radioactivity in breast lesions. In addition to assessment of lesion activity, lesion volume estimates are necessary to quantify lesion radioactivity concentration. We have used multiple view x-ray imaging as a means of estimating lesion volume. Using phantom experiments, we have empirically derived a formula for correction of the measured z dimension of the lesion. The error obtained in quantification of lesion activity is approximately 10%. Lesion volume can be assessed with an accuracy comparable to that of lesion activity assessment using five x-ray views. These results suggest that the error in lesion concentration assessment is approximately 14%.
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Objective @#To develop an analytical method of ibotenic acid (IBA) and muscimol (MUS) in wild mushroom by dansyl chloride (DNSCl) derivatization-liquid chromatography-tandem mass spectrometry (LC-MS/MS), and to provide technical support for etiological identification of mushroom poisoning events.@*Methods @#The sample was extracted with hydrochloric acid solution, derived by bimolecular DNSCl, diluted and inorganic salts precipitated with acetonitrile. The extract was separated by a waters XBridgeTM BEH C18 column and measured by LC-MS/MS.@*Results @#The limits of detection for IBA and MUS in wild mushroom were 0.15 mg/kg and 0.1 mg/kg, respectively. Good linear relationship was obtained for IBA and MUS at the range of 0.5-250 mg/kg with the correlation coefficient of 0.997 and 0.999, respectively. The average recoveries at three spiking levels were 84.5%-102.0% with relative standard deviations (RSDs, n=6) of 4.7%-8.6% for IBA. The average recoveries were 88.6%-95.4% with RSDs (n=6) of 4.9%-7.5% for MUS. @*Conclusion @#The optimized sample extraction and bimolecular DNSCl derivatization conditions can achieve rapid and accurate analysis of IBA and MUS in wild mushroom poisoning sample.
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An improved method for fast scanning and fluorescence detection on multimicrochannel microchips is presented using acousto-optic-deflection-driven laser-beam scanning. A microprocessor embedded subsystem used in conjunction with LabView program as the human-machine interface for control of laser-beam scanning and data preprocessing allowed faster scanning and addressing speeds to be attained and improved attenuation calibration and the data sampling speed. This system allows for flexible, high-resolution fluorescence detection for multimicrochannel electrophoresis in a manner that can be applied to a number of high-throughput analysis applications. Incorporating an F-theta focusing lens into the optical set-up allowed for a laser spot as small as 10 microm to accurately be addressed to the center of microchannels. With this spot size, it will be possible to further increase the channel density in the scanning range without encountering crosstalk. Using a six-channel microchip (four separation channels, two alignment channels), the simultaneous separation and fluorescence detection of amino acids and DNA digest samples in four channels is illustrated. User-friendly interpretation of the separation data is facilitated not only by a peak alignment/normalization routine developed within the software, but also through improved signal-to-noise ratios obtained through exploitation of signal processing.
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Eletroforese Capilar/instrumentação , Eletroforese Capilar/métodos , Processamento de Sinais Assistido por Computador , Espectrometria de Fluorescência/métodos , Acústica/instrumentação , Aminoácidos/análise , Calibragem , DNA/análise , Desenho de Equipamento , Lasers , Miniaturização , Modelos Teóricos , Óptica e Fotônica , Semicondutores , Sensibilidade e Especificidade , Processos EstocásticosRESUMO
A proteomic analysis method, two dimensional gel electrophoresis (2-DE) followed by matrix-assisted laser desorption/ionization time-of-flight MS (MALDI-TOF-MS), was used to explore the link between plasma proteome and the different syndromes of traditional Chinese medicine (TCM) in patients with chronic hepatitis B (CHB). In compared with the plasma proteomes from health donors, the alterations in protein expression from cases of the five TCM syndromes, including damp heat stasis in the middle-Jiao syndrome, liver Qi stagnation and spleen deficiency syndrome, spleen and kidney Yang deficiency syndrome, liver and kidney Yin deficiency syndrome, and blood stasis into collateral syndrome with CHB were identified (P<0.05). In the cases of the five TCM syndromes with CHB, immunoglobulin J-chains (IGJ) and C-reactive protein (CRP) were up-regulated, while haptoglobin (HPT), retinol binding protein (RBP) and vitronectin were down-regulated. To further confirm these results, four proteins, including CRP, IGJ, HPT and RBP, from more plasma samples were quantified by ELISA. The results showed that the changes of protein levels were consistent with those from the 2-DE experiment. Importantly, the upregulation tendency of IGJ level in plasma is related with the different TCM syndromes with CHB (P<0.05). Our results show that IGJ may serve as a novel potential biomarker for diagnosis of the different TCM syndromes in patients with CHB.
Assuntos
Proteínas Sanguíneas/análise , Hepatite B Crônica/sangue , Medicina Tradicional Chinesa , Proteoma/análise , Deficiência da Energia Yang/sangue , Deficiência da Energia Yin/sangue , Eletroforese em Gel Bidimensional/instrumentação , Eletroforese em Gel Bidimensional/métodos , Ensaio de Imunoadsorção Enzimática , Hepatite B Crônica/diagnóstico , Humanos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/instrumentação , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , SíndromeRESUMO
We developed an empirical PET model taking into account system blurring and a blind iterative reconstruction scheme that estimates both the actual image and the point spread function of the system. Reconstruction images of high quality can be acquired by using the proposed reconstruction technique for both synthetic and experimental data. In the synthetic data study, the algorithm reduces image blurring and preserves the edges without introducing extra artifacts. The localized measurement shows that the performance of the reconstruction image improved by up to 100%. In experimental data studies, the contrast and quality of reconstruction is substantially improved. The proposed method shows promise in tumor localization and quantification.