Changes in Gel Characteristics, Rheological Properties, and Water Migration of PSE Meat Myofibrillar Proteins with Different Amounts of Sodium Bicarbonate.

The changes in the gel and rheological properties and water-holding capacity of PSE meat myofibrillar proteins with different amounts of sodium bicarbonate (SC, 0−0.6/100 g) were studied. Compared to the PSE meat myofibrillar proteins with 0/100 g SC, the texture properties and cooking yield significantly increased (p < 0.05) with increasing SC; meanwhile, adding SC caused the gel color to darken. All samples had similar curves with three phases, and the storage modulus (G') values significantly increased with the increasing SC. The thermal stability of the PSE meat myofibrillar proteins was enhanced, and the G' value at 80 °C increased with the increasing SC. Because water was bound more tightly to the protein matrix, the initial relaxation times of T21 and T22 shortened, the peak ratio of P21 significantly increased (p < 0.05), and the P22 significantly decreased (p < 0.05), which implied that the mobility of the water was reduced. Overall, SC could improve the thermal stability of the PSE meat myofibrillar proteins and increase the water-holding capacity and textural properties of the cooked PSE meat myofibrillar protein gels.

Effect of sodium bicarbonate on techno-functional and rheological properties of pale, soft, and exudative (PSE) meat batters.

In the study, changes in salt-soluble protein (SSP) content, gel properties, rheological characteristic, and microstructure attributes of pale, soft, and exudative (PSE) pork batters with different concentrations of added sodium bicarbonate (0-0.6%) were investigated. The pH, b⁎ value, SSP content, cooking yield, texture properties, emulsion stability, and G' values at 72 °C significantly increased with the increase in sodium bicarbonate, but the texture properties and G' values of the samples with 0.4% and 0.6% did not significantly different, while the a⁎ value significantly decreased. Moreover, a greater G' value at 72 °C was in agreement with a higher hardness value of meat batter. The microstructure of cooked PSE meat batters with 0% and 0.2% sodium bicarbonate had a dense structure, and samples with 0.4% and 0.6% had some large cavities. In conclusion, the use of sodium bicarbonate can enhance the water holding capacity, texture and rheological properties of PSE meat batters by increasing their pH, SSP content, and emulsifying stability.

[Determination of Haloacetic Acids, Disinfection Byproducts, in Tap Water with Reversed-Phase Ultra-Performance Liquid Chromatography-High Resolution Mass Spectrometry].

Objective: To establish a method for quantitative analysis of haloacetic acids (HAAs), disinfection byproducts, in tap water with reversed-phase ultra-performance liquid chromatography-quadrupole-orbitrap high resolution mass spectrometry. Methods: Tap water samples were collected and 0.70 g/L ascorbic acid was added to eliminate residual chlorine. Then, the water samples were directly injected into the instrument for analysis after filtration. After separation on a pentafluorobenzene (PFP) column with an inner diameter of 1.0 mm at a higher linear velocity and a lower volume flow rate compared with those of a narrow-bore column, nine HAAs, namely, monochloroacetic acid (MCAA), monobromoacetic acid (MBAA), dichloroacetic acid (DCAA), bromochloroacetic acid (BCAA), dibromoacetic acid (DBAA), trichloroacetic acid (TCAA), bromodichloroacetic acid（BDCAA), chlorodibromoacetic acid (CDBAA) and tribromoacetic acid (TBAA), were examined by negative electrospray ionization and full MS/dd-MS 2 acquisition mode. In order to adjust for the matrix effect, matrix matching calibration curves were used to quantitate the nine HAAs. Results: Good linearity was obtained for each of the nine HAAs within their respective linear ranges. The detection limits and quantification limits of the method were 0.020-1.0 µg/L and 0.060-3.0 µg/L. The recoveries were 69.8%-119%. Conclusion: The proposed method showed strengths in separation speed and qualitative accuracy. It did not require for complicated pretreatment procedures and can meet the need of tap water sample analysis.

[The Screening Approaches for 34 Common Drugs and Metabolites in Biological Samples by Liquid Chromatography Orbital Trap Mass Spectrometry].

Objective: To establish a high-performance liquid chromatography orbital trap mass spectrometry (HPLC-Obitrap MS) method for screening 34 common drugs and metabolites in biological samples. Methods: The target analytes in urine and blood samples were extracted with ethyl acetate, concentrated by nitrogen blowing and redissolved. The hair samples were washed with water and acetone, dried and cut into bits of about 1 mm, and then crushed in a freezing grinder. The analytes were extracted with methanol, and after filtration, the filtrate was used for instrumental analysis. Hypersil Gold PFP (2.1 mm×100 mm, 3 µm) column was used for chromatographic separation. Methanol and 5 mmol/L ammonium acetate solution were used as mobile phase with gradient elution at a flow rate of 400 µL/min. Mass spectrometry was done by electrospray positive and negative ion alternation mode. The data were collected using Full MS and Full MS/dd-MS2 mode. Xcalibur 4.0 software was used to control instruments and to collect data, and TraceFinder 3.3 was used for screening and identification. Results: The method's detection limits for 34 drugs and their metabolites in blood, urine and hair samples were 3.30-10700 ng/L, 4.43-5440 ng/L, 0.0350-4.21 µg/kg, respectively. The intra-day and inter-day precisions of the spiked samples at the levels of 5.0, 10, and 20 µg/L were 3.50%-6.00% and 4.18%-9.90%, respectively. A total of 1125 biological samples of urine, blood and hair were collected and screened. The results showed that 96.7% of the drug users were taking a single drug, while 3.3% were mixed drug users. The main types of drug of abuse were methamphetamine (75.8%), heroin (18.5%), ketamine (2.4%) and other drugs (3.3%), and 87.9% of the positive samples were from male users. Compared with the results of high-performance liquid chromatography triple quadrupole mass spectrometry, this method can be used to identify more types of drugs in one run and to conduct retrospective analysis. Conclusion: The method established in the study is simple and sensitive and is well suited for the screening of common drugs and metabolites in biological samples.

[Study on the Analytical Method of Solid Phase Extraction-Ultra Performance Liquid Chromatography Tandem Quadrupole Linear Ion Trap Mass Spectrometry for 12 Perfluorinated Compounds in Human Urine].

OBJECTIVE: To establish a method for simultaneous determination of 12 kinds of perfluorinated compounds (PFCs) in human urine based on ultra performance liquid chromatography tandem quadrupole linear ion trap mass spectrometry (UPLC-QTtrap-MS). METHODS: After pH adjustment with 2% formic acid, the urine samples were loaded on a WAX solid phase extraction (SPE) cartridge for extraction, purification and concentration. The eluates were collected, concentrated to dryness under nitrogen, and reconstituted with 10 mmol/L ammonium acetate aqueous solution-methanol ( V water∶ V methanol = 70∶30) before injection. UPLC was performed on a C 18 cartridge, and methanol and 10 mmol/L ammonium acetate aqueous solution was used as mobile phases with gradient elution. QTtrap-MS was operated in multiple reaction monitoring (MRM) mode, and the internal standard calibration curves were applied for quantitative analysis. RESULTS: Good linearity was obtained in the linear range, with the method detection limits and method quantification limits being 0.032 ng/L-6.5 ng/L and 0.10 ng/L-21 ng/L, respectively, for the 12 kinds of PFCs. The spiked recoveries of the 12 kinds of PFCs were 91.5%-114%, with the intra-day precision and the inter-day precision being 0.57%-16.0% and 1.88%-20.1%, respectively. The established method was applied to the determination of 12 kinds of PFCs in the urine samples of primary school students collected in one area. Nine kinds of PFCs were detected in the urine samples in this area. Among the PFCs detected, perfluorobutanesulfonic acid (PFBS) and perfluorooctanoic acid (PFOA) were the main PFCs found in the student urine samples. CONCLUSION: The method established in this study could be used to simultaneously examine 12 kinds of PFCs in urine. The method combined SPE with isotope internal standard correction and achieved good sensitivity and accuracy.

[Determination of Aromatic Compounds Metabolites in Human Urine by Solid Phase Extraction-liquid Chromatography-Tandem Mass Spectrometry].

OBJECTIVE: To establish the method based on high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) with solid phase extraction (SPE) for simultaneous determination of the biological metabolites of aromatic compounds, including N-acetyl-S-phenyl-L-cysteine (SPMA), N-acetyl-S-benzyl-cysteine (SBMA), p-nitrophenol (PNP), methylhippuric acids (MHA), p-Aminophenol (PAP), mandelic acid (MA), phenylglyoxylic acid (PGA) and 1-hydroxypyrene (1-OHP) in urine. METHODS: After adding 20 µL of ß-glucuronidase and 1 mL ammonium acetate buffer solution in 1 mL of urine, the sample was digested in a 37 ℃ incubator for 20 h. After digestion, the enzymatic hydrolysate was purified by PRIME HLB solid phase extraction column. The target compounds were eluted with 4 mL of acetonitrile and blown to dryness with nitrogen, reconstituted with 0.20 mL of methanol. Injected the sample solution into LC-MS/MS system for analysis after filtering with 0.22 µm filter membrane. LC separation was carried out on a reversed-phase C18 column (2.1 mm×150 mm, 3.5 µm); gradient eluting was performed at a flow rate of 0.2 mL/min. The water containing 0.1% formic acid was used as mobile phase A and methanol was used as mobile phase B. The mass spectrometry was performed with multiple reaction monitoring (MRM) mode, using alternating positive and negative ions, and internal standard curves were used for quantification. RESULTS: The eight metabolites showed good linearity within the range of 1-100 ng/mL, with a correlation coefficients greater than 0.995, and the relative precision deviation (RSDs) was 0.050%-9.95%. The method detection limits (MDLs) of the eight target metabolites were 0.041-0.12 ng/mL. The proposed method was used for urine sample analysis and the spiked recoveries were 80.1%-114.0%. CONCLUSION: The established method is quick, sensitive and accurate; it meets the requirementof the biological monitoring of aromatic compounds for the general population and occupational population.

[Determination of 8-oxo-2'-deoxyguanosine and Cotinine in Urine by Hydrophilic Chromatography-tandem Mass Spectrometry with Isotope Dilution].

OBJECTIVE: To develop an assay for determination of 8-oxo-2'-deoxyguanosine and cotinine in human urine by hydrophilic chromatography tandem mass spectrometry (HILIC-MS/MS) with isotope dilution. METHODS: The urine supernatant was 1∶5 diluted with 3 mmol/L ammonium formate aqueous solution containing 15N 5-8-OHdG and D 3-cotinine as internal standard. After being filtered through a 0.22 µm water filter, the sample solution was injected into ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) for analysis. Separation was performed on ACQUITY UPLC® BEH HILIC column (50 mm×3.0 mm, 1.7 µm) with isocratic elution (A∶B=10∶90) at 40 ℃. The mobile phase was composed with acetonitrile (B) and 3 mmol/L ammonium formate water soulution (A). The flow rate was 0.3 mL/min. Positive ion scan-multiple reaction monitoring (MRM) mode were used for monitoring and internal standard curves were applied for quantification. RESULTS: Good linearity was obtained under the optimal conditions. Detection limits for 8-OHdG and cotinine were 0.064 µg/L and 0.035 µg/L respectively, the quantitation limits were 0.21 µg/L and 0.12 µg/L respectively, and the recoveries of the spiked urine samples were 92.6%-102% and 102%-106% respectively. Statistical analysis of 40 urine sample determination results obtained by using the above assay showed that there were significant differences in tobacco smoke exposure and tobacco-specific nitrosamine intake between active and passive smoker ( P<0.05). The concentration of NNAL and cotinine were higher in urine samples of active smoker. Tobacco smoke exposure was positively correlated with tobacco specific nitrosamine intake in both active and passive smokers (the correlation coefficients were 0.487 and 0.786 respectively, P<0.05). CONCLUSION: We successfully established a simple and fast assay for simultaneously detecting 8-oxo-2'-deoxyguanosine and cotinine in human urine. It was sensitive and accurate for quntification via the calibration by the isotope internal standards, and can meet the needs of batch analysis.

[Detecting Nicotine and Cortinine in Hair by Hydrophilic Interaction Liquid Chromatography Tandem Mass Spectrometry].

OBJECTIVE: To develop a method for detecting nicotine and cotinine in hair by hydrophilic interaction chromatography tandem mass spectrometry. METHODS: Hair samples were hydrolyzed in sodium hydroxide solution before extraction with dichloromethane. The samples were blown to dry with nitrogen and dissolved with mobile phase. The filtrate of the samples was injected into a chromatographic-mass spectrometry system for analysis. The separation was performed by a hydrophilic column, with which methanol-0.1% ammonia was used as the mobile phase. The quantitative detection of Nicotine and Cortinine was carried out with electron spray ionization-triple quadrupole mass spectrometry. The established method was used for detecting nicotine and cotinine in 602 hair samples of pregnant women and 31 hair and urine samples of volunteers. RESULTS: A standard curve was drawn for the established method of hydrophilic liquid chromatography tandem mass spectrometry. Good linearity was obtained for detecting nicotine and cotinine in the range of 0.030-100.000 µg/L, with a detection limit (MDL) of 0.007 6 µg/g and 0.004 4 µg/g, respectively. The inter-day and intra-day precisions reached a level of less than 10%. The recoveries of the spiked samples ranged from 81.0% to 102.0%. About 0.020-0.260 µg/g nicotine and 0.004 8-0.069 0 µg/g cotinine were detected in the pregnant women without exposure to secondhand smoking (SHS), compared with 0.029-0.350 µg/g nicotine and 0.005 6-0.085 0 µg/g cotinine in those exposed to SHS. Nicotine and cotinine were also found in the hair and urine samples of volunteers, which were correlated with smoking (P < 0.05). A dose-response relationship were found between smoking and hair nicotine. CONCLUSIONS: The proposed method is accurate and sensitive for detecting nicotine and cotinine in hair samples. Hair nicotine can be a specific biomarker for assessing exposure to tobacco smoking.

[Detection of 11 Organophosphate Pesticides and Atrazine in Water by Dispersive Liquid-Liquid Microextraction Combined with Gas Chromatography Mass Spectrometry].

OBJECTIVE: To develop a method for detecting 11 organophosphate pesticides and atrazine in water samples by dispersive liquidliquid microextraction combined with gas chromatographymass spectrometry (DLLMEGC/MS) . METHODS: DLLME and GCMS parameters were optimized for efficient extraction of chemicals. The proposed method was used for detecting organophosphate pesticides in tap water and river water samples,with 200 µL of dimethylbenzene as extractant and 800 µL of methanol as dispersant. They were mixed,emulsified and dispersed into 10 mL of water samples. The extractant (1 µL) from centrifugation was injected into the GC/MS system for analyses. GC separation was performed on HP5 column (30 m×0.25 mm,0.25 µm) by temperature programming. Mass spectrometric analysis was done with EI and selected ion monitoring (SIM) mode was used for quantitative analysis. RESULTS: Good linear ranges for detecting the 11 pesticides and atrazine appeared from 2.0 ng/mL to 50 ng/mL,with a limit of 0.121.38 ng/mL. The relative standard derivations (RSDs) ranged from 5.57% to 9.85%. The average recoveries ranged from 75.5% to 107%. CONCLUSION: The method is sensitive and rapid,with simultaneous extraction and concentration procedures. The lowdensity organic solvent after extraction is easy to isolate. The method fits for analyses of organophosphate pesticides and atrazine in water samples.

Bone marrow mesenchymal stem cells repair cadmium-induced rat testis injury by inhibiting mitochondrial apoptosis.

Cadmium is a highly toxic metal with widespread exposure to people that can cause tissue injuries that lack effective treatment. The aim of this project was to uncover whether bone marrow mesenchymal stem cells (BMSCs) can repair cadmium-induced rat testis injury and to explore the role of mitochondrial apoptosis in this process. To this end, 21 adult male Wistar rats were randomly divided into control, model and therapy groups, 7 each, and were administered 0, 0.4 and 0.4 mg/kg body weight CdCl2 saline solution, respectively, by intraperitoneal injection 5 times per week for 5 weeks. Then, rats in the therapy group were treated with 107 BMSCs by retro-orbital injections, while the others were given equal volumes of phosphate buffered saline. Following 2-week BMSCs-treatment, the therapy rats were heavier than the model rats, despite there being no difference in testicular cadmium contents between these groups, which were both significantly higher than the control group. BMSCs were observed in the testis of the therapy rats, in which pathological changes improved significantly compared with the model group. Expression of the apoptosis-associated proteins Bim, Bax, Cytochrome C, Caspase-3, active-Caspase-3 and AIF increased, while Bcl-2 was reduced significantly in rat testes of model group compared with the other groups. Based on these findings, we conclude that cadmium can accumulate in rat testes where it caused severe tissue injury, BMSCs can be localized to the injured testicular tissue of rats and repair the tissue injury, these reparative effects may be highly related with mitochondrial apoptosis.

[Determination of Nicotine and Cotinine in Urine by Dispersive Liquid-Liquid Microextraction Combined with Gas Chromatography-Mass Spectrometry].

OBJECTIVE: To develop a method for the determination of nicotine and cotinine in urine samples by dispersive liquid-liquid microextraction (DLLME) combined with gas chromatography-mass spectrometry (DLLME-GC/MS). METHODS: The experimental conditions for GC-MS and DLLME were investigated in detail. DLLME was performed with the following procedure: 5 mL of urine sample was adjusted to pH9. 0 with NaOH solution; NaCl was added to increase ionic strength; 100 µL chloroform (containing internal standard of quinolone) as extractant was mixed with 1 000 pL methanol as dispersant and then injected into the urine sample to make it emulsified and dispersed. The sample solution was centrifuged for 5 min at 4,000 r/min, and 1 µL of its extraction solvent was injected into the GC/MS system for analysis. GC separation was performed with DB-5 column under programmed temperature. Nicotine and cotinine were quantified using selected ion monitoring (SIM) mode of mass spectrum detection and internal standard working curve. RESULTS: Good linear relationship was obtained for detecting nicotine and cotinine ranging from 0. 2 ng/mL to 100 ng/mL, with a detection limit of 0. 010 ng/mL and 0. 022 ng/mL for nicotine and cotinine respectively. The relative standard derivation (RSD) for determination of nicotine and cotinine in urine samples were 8.2% and 9.6% respectively. The spiked recoveries ranged from 92.0% to 108.0% for nicotine, 83.0% to 110.0% for cotinine. CONCLUSION: The method is rapid, sensitive, accurate and simple, with little consumption of organic solvent. It is suitable for determination of nicotine and cotinine in urine, and can meet the requirements for evaluating human tobacco exposure.

[Effectiveness of CLAT Protocol for Treating Patients with Refractory Acute Myeloid Leukemia].

OBJECTIVE: To explore the clinical efficacy and toxicity of CLAT protocol (cladribine, cytarabine and topotecan) for treating patients with refractory acute myeloid leukemia (R-AML). METHODS: A total of 18 patients with R-AML (median age 37 years, range 18 to 58 years; male n = 16, female n = 2) were treated with CLAT protocol, which consisted of cladribine 5 mg/m(2)/d, i.v. on days 1-5, cytarabine 1.5 g/m(2)/d, i.v. on days 1-5, topotecan 1.25 mg/m(2)/d, i.v. on days 1-5 and G-CSF 300 µg/d subcutaneous injection on day 6 until neutrophile granulocyte recovery. RESULTS: Out of 18 patients 2 died of severe infection before the assessment. Among 16 evaluated patients, 10 (55.6%) achieved complete remission (CR), and 2 (11.1%) achieved partial remission (PR), the overall response rate was 66.7%, the rest 4 patients did not respond (NR). The median overall survival time and DFS for the CR patients was 9.5 months (95%CI: 6.7-16.64) and 9.5 months (95%CI: 6.1-16.7) respectively. The 1 year OS and DFS rates were 45% and 46.9%, respectively. All patients developed grade 4 of granulocytopenia and thrombocytopenia, the median duration was 13 (range 2 to 21) days and 12 days (range 2 to 21), respectively, all patients developed infection, 2 patients died of severe infection. The most common non-hematological side effects included nausea, vomiting, diarrhoea, rash, aminotransferase or bilirubin elevation and were grade 1 to 2. CONCLUSION: The CLAT protocol seems to have promising for the treatment of refractory AML patients, and patients well tolerated. This CLAT protocol offers an alternative treatment for R-AML patients who received severe intensive treatment, especially with anthracycline-containing chemotherapy.

[Detecting Thallium in Water Samples using Dispersive Liquid Phase Microextraction-Graphite Furnace Atomic Absorption Spectroscopy].

OBJECTIVE: To develope a method of solvent demulsification dispersive liquid phase microextraction (SD-DLPME) based on ion association reaction coupled with graphite furnace atomic absorption spectroscopy (GFAAS) for detecting thallium in water samples. Methods Thallium ion in water samples was oxidized to Tl(III) with bromine water, which reacted with Cl- to form TlCl4-. The ionic associated compound with trioctylamine was obtained and extracted. DLPME was completed with ethanol as dispersive solvent. The separation of aqueous and organic phase was achieved by injecting into demulsification solvent without centrifugation. The extractant was collected and injected into GFAAS for analysis. With palladium colloid as matrix modifier, a two step drying and ashing temperature programming process was applied for high precision and sensitivity. RESULTS: The linear range was 0.05-2.0 microg/L, with a detection limit of 0.011 microg/L. The relative standard derivation (RSD) for detecting Tl in spiked water sample was 9.9%. The spiked recoveries of water samples ranged from 94.0% to 103.0%. CONCLUSION: The method is simple, sensitive and suitable for batch analysis of Tl in water samples.

Association of increased circulating catecholamine and glucocorticoid levels with risk of psychological problems in oral neoplasm patients.

BACKGROUND: Noradrenergic pathways and glucocorticoid-mediated signal pathways have been implicated in the growth and progression of oral cancer. Patients with oral neoplasms can have high psychological distress levels, but the effects of stress-related hormones on oral neoplasm growth are unknown. METHODS: We have investigated the relationships between pre-surgical measurements of psychological problems with Symptom Checklist-90-revised Inventory (SCL90-R), tumor histology, circulating blood catecholamine and glucocorticoid levels among 75 oral neoplasm patients, including 40 oral cancer patients and 35 benign oral tumor patients. RESULTS: The results showed that most dimension scores of SCL90-R did not show a significant difference between the two groups except depression (p = 0.0201) and obsessive-compulsion (p = 0.0093), with the scores for these symptoms being higher among oral cancer group versus the benign oral tumor group. The differences of total score, average score and other monomial factor scores were not statistically significant. The mean concentrations of catecholamine and glucocorticoid in peripheral blood of the oral cancer group were higher than those in benign oral tumor group (p<0.01). We also examined whether associations observed between biobehavioral measures and circulating blood catecholamine and glucocorticoid levels extended to other compartments in the oral cancer group. CONCLUSIONS: These findings suggest that stress hormones may affect oral cancer behavior by influencing the tumor micro-environment though the circulating blood.

[Determination of organochlorine pesticides in water using solidification of floating organic drop liquid phase microextraction by gas chromatography].

OBJECTIVE: To develop a new method for simultaneous determination of eight organochlorine pesticides (OCPs) in water samples using solidification floating organic drop liquid-phase microextraction (SFO-LPME) combined with gas chromatography-electronic capture detector (GC-ECD). METHODS: The experimental conditions of SFO-LPME were determined with n-Hexadecane as extractant, water samples adjusted to pH 6.0, inonic strength increased by adding 15.0 g/100 mL NaCI. The OCPs were extracted at 55 degrees C for 10 mm and determined with GC-ECD. RESULTS: A good linearity (correlation coefficients > or = 0.996) was obtained for eight target compounds from 5 ng/I. to 100 ng/L. The method detection limits ranged from 0.24 ng/L to 0.78 ng/L. Satisfactory results were achieved with samples of river water, piped water and farmland water, with an average recovery of 76.0%-106.0% and RSD of 3.24%-11.60%. CONCLUSION: The proposed method is rapid, simple and sensitive. It is suitable for hatch analyses of eight organic chlorine pesticides in water samples.

[Simultaneous determination of adrenaline, noradrenaline, cortisone and cortisol in plasma with HPLC/MS/MS].

OBJECTIVE: To develop a method for simultaneous determination of adrenaline, noradrenaline, cortisone and cortisol in plasma using HPLC/MS/MS. METHODS: Sample proteins were precipitated with acetonitrile and the sample solution was injected into HPLC/MS/MS after centrifugation at 15,000 r/min for 5 min. Electrospray ionization (ESI) and the positive ion detection were applied with a multiple reaction monitoring (MRM) mode for quantitative analyses. RESULTS: Under the optimal conditions, good linearity (r > 0.999) was observed in the range of 0.02-200.00 ng/mL of target compounds. The detection limit reached 4.13 pg/mL, 4.64 pg/mL, 4.29 pg/mL and 4.52 pg/mL for adrenaline, noradrenaline, cortisone and cortisol respectively. The inter-day and intra-day precisions ranged from 1.19%-5.42% and 2.16%-6.04% respectively. Satisfied results were achieved using human plasma samples, with a spiked recovery in the range of 80.0%-109.0% and a relative standard deviation of 3.93%-7.57%. CONCLUSION: The proposed method is quick, sensitive and suitable for batch analyses of plasma samples.

[Assessment of mental health status in oral squamous cell carcinoma patients and its correlation with catecholamines level].

PURPOSE: To investigate the relationship between mental health status and catecholamines level in oral squamous cell carcinoma patients. METHODS: Forty patients with oral squamous carcinoma (OSCC) who were diagnosed in West China School of Stomatology between Dec. 2011 and Aug. 2012, were assessed with symptom checklist-90 (the 5-grade scoring of 0 to 4 points was used) independently according to their actual conditions. Blood sample was taken on the second admission day and fresh tumor tissue with the weight of 0.5 g was obtained. A method was developed for determination of catecholamine and glucocorticoid in serum using liquid chromatography-tandem mass spectrometry (HPLC-MS-MS). SPSS19.0 software package was used for statistical analysis. RESULTS: Forty patients were included in the study. Compared with the scores of SCL-90 in national norms, the scores were all higher in oral squamous carcinoma patients except the interpersonal relationship. Epinephrine(E) and norepinephrine(NE) in serum was (70.27±34.50) pg/mL and (316.73±109.22) pg/mL, respectively. E and NE in tumor tissues was (6.66±3.58) pg/mg and (12.67±5.27) pg/mg respectively. As the concentrations of NE and E from circulating serum increasing, the stage and grade of oral squamous carcinoma were promoted. CONCLUSIONS: Psychiatric factors have an important impact on OSCC patients. The increased level of catecholamines is closely related to clinical stage and grade of OSCC. Supported by National Natural Science Foundation of China (81172578) and Natural University Students Innovation Training Program (201210610096).

[Determination of canthaxanthin and astaxanthin in egg yolks by reversed phase high performance liquid chromatography with diode array detection].

OBJECTIVE: A method using reversed phase high performance liquid chromatography (RP-HPLC) coupled with diode array detector (DAD) was developed for the simultaneous determination of canthaxanthin and astaxanthin in egg yolks. METHODS: Samples were extracted with acetonitrile in ultrasonic bath for 20 minutes and then purified by freezing-lipid filtration and solid phase extraction (SPE). After being vaporized to dryness by nitrogen blowing and made up to volume with methanol, the extract solution was chromatographically separated in C18 column with a unitary mobile phase consisting of acetonitrile. The proposed method was validated in terms of linearity, precision, accuracy, and limit of detection (LOD). RESULT: Regression analysis revealed a good linearity between peak area of each analyte and its concentration (r > or = 0.998). The intra- and inter-day relative standard deviations (RSDs) were less than 3.6% and 5.2%, respectively. LODs of canthaxanthin and astaxanthin were 0.035 and 0.027 microg/mL (S/N = 3). The average recoveries of canthaxanthin and astaxanthin were 91.5% and 88.7%. CONCLUSION: The proposed method is simple, fast and easy to apply.

[Determination of histatins 5 in salivary by reversed-phase high performance liquid chromatography method with ultraviolet detection].

OBJECTIVE: The determination method of histatins 5 in human saliva with reversed-phase high performance liquid chromatography (HPLC) was developed. METHODS: Salivary samples were collected and diluted with phosphate buffer (pH 2.5). The upper solution was determined with HPLC. Phosphate buffer (pH 3.5) of the mobile phase and C18 column was used throughout the experiment. The detection wavelength was 276 nm. RESULTS: The linear ranges were 1.0-50.0 microg x mL(-1). The detection limit was 0.12 microg x mL(-1). The relative standard derivations (RSD) of standard solution for reserved time and peak area were 0.68% and 4.13% respectively. The proposed method was applied for analysis of salivary samples and the satisfactory results were obtained. RSD for sample determination was 4.41% and the average recoveries were 88.4%-109.0%. CONCLUSION: The method was quick, simple and accurate. Analytical time was less than 15 min. It was adapted for analysis of salivary histatins 5 in salivary samples.

[Rapid determination of ethanol in blood by capillary-gas chromatography].

OBJECTIVE: To develop a method for the rapid determination of ethanol in blood with capillary-GC. METHODS: 0.50 mL of whole blood sample was taken and added with 1.00 mL of dimethyl sulfoxide (DMSO), and 2 g of anhydrous sodium sulfate. The supernatant of the sample solution was directly injected into GC for analysis. RESULTS: Ethanol was separated from other substances in the sample. The liner range of ethanol detected by the capillary-GC was 0.0-300.0 mg/100 mL, and the detection limit was 0.2 mg/100 mL. The RSD for standard solution determination was 1.36%. Satisfactory results were obtained for the determination of ethanol in whole blood samples, with recoveries ranging from 90.9% to 107.3% and a RSD of 1.98%. The combined uncertainty was 2.2%. CONCLUSION: This is a rapid, sensitive and simple method for determination of ethanol in large quantities of samples. The method has shortened the duration of analysis cycle in comparison with the traditional headspace-GC, with a reduction from 20-30 min to less than 10 min.