Qualitative screening and quantitative determination of multiclass water-soluble synthetic dyes in foodstuffs by liquid chromatography coupled to quadrupole Orbitrap mass spectrometry.

A LC-Q-Orbitrap HRMS analytical method for both qualitative screening and quantitative determination of 90 synthetic dyes including ten groups of isomers in foods has been established. An in-house synthetic dyes database and characteristic ions were also developed. Based on Q-Orbitrap HRMS, mass spectrum and fragmentation patterns of synthetic dyes were studied, which indicated that double charged ions were usually the main precursor ions. Matrix effects were successfully eliminated by the C18 d-SPE clean-up coupled with dilute and shoot approach with methanol-water (1:4, v/v) in 100-fold. For most of the compounds, mean recoveries were satisfactory between 70% and 120% with RSD < 20% at three spiked level in the range of 0.025-1.0 mg/kg. The screening detection limits ranged from 0.025 - 1.0 mg/kg. Method validation showed that the established method was efficient, rapid and high-throughput, which has been successfully applied to the monitoring of these water-soluble synthetic dyes in foods.

Primary anorectal malignant melanoma: a case report.

Anorectal melanoma (ARM) is rare and lethal. We report a case of a 48-year-old woman with 9 months of rectal swelling and bleeding. Physical examination revealed a mass about 5 × 6 cm on the anterior wall of the rectum, 3 cm from the anal verge, and the patient underwent abdominoperineal resection (APR). After hematoxylin-eosin staining and immunohistochemical staining, it was considered an ARM, which is an aggressive disease with a poor survival. Immunohistochemical staining showed the tumor to be positive for S-100, Melan A, Ki67 proliferative index of 70%, and negative for HMB45. The melanoma had infiltrated the adventitia and metastasized to the (intestinal) 16/16 lymph nodes with cancerous nodule formation. There were multiple organs with metastasis (liver, spleen, pancreas, lung and subcutaneous soft tissue) three months after operation. Overall, pre-operative biopsy may be insufficient to make a definite diagnosis, and immunohistochemistry is necessary. Therefore, the gold standard treatment for ARM is oncological radical surgical resection.

Simultaneous determination of multiclass illegal dyes with different acidic-basic properties in foodstuffs by LC-MS/MS via polarity switching mode.

Simultaneous determination of multiclass illegal dyes possessing different chemical properties is difficult. By using LC-MS/MS via negative/positive ion switching mode, an efficient and fast multi-residual method for simultaneous determination of multiclass 52 illegal dyes with different acidic-basic properties in foodstuffs was developed and validated during one single run, including 23 fat-soluble neutral azo dyes, 8 acidic sulfonated azo dyes, 12 triphenylmethane basic dyes, three basic indole dyes, three xanthene dyes, one quinoline dye, and two anthraquinones dyes. The illegal dyes were extracted with methanol-acetonitrile and further purified with d-SPE procedure to reduce interference. Sample dilution with 100-fold was used for the elimination of matrix effects of the quantitation of LC-MS/MS analysis. Validation data showed the good recoveries in the range of 71.2-111.2%, with relative standard deviations less than 20%, suggesting the developed method is suitable for the identification and quantitation of multiclass illegal dyes at trace levels in foods.

[Epidemiological characteristic of first case of locally identified A/H1N1 secondary cases caused by imported source of infection in China].

OBJECTIVE: To study the first locally identifed A/H1N1 secondary cases outbreak in China. METHODS: Interview and field investigation were integrated to describe the whole process of transmission on each case and to illustrate the relationships between the onset of the disease and the retated factors. RESULTS: Two contact persons appearanced fever and whose throat swabs were tested positive to H1N1 viral nucleic acid. The two had a history of contact in a short distance with the initial imported case without any protective measure in the poor air ventilation. The patients clinical situation was slight. The incubation was between 37 hours and 57 hours. No other new case was found after intervention as isolation and antisepsis were taken. CONCLUSION: This event was proved to be an outbreak of local A/H1N1 secondary cases caused by the imported case. The main mode of transmission was personal contact in a short distance without protection, through air and droplet. The locus with poor air ventilation was high risk place. Contact persons should be observed seven days and tested continuously. Infectivity and pathogenicity of the A/H1N1 virus were limited and appeared weakened by generations. Patient's condition was related with persistence and frequency of contact with the infection sources. Enhancing management of contact persons, health education, early diagnose, early treatment and early insulation were effective measures of controling and prenventing the spread A/H1N1.

[Investigation on a seasonal influenza accompanying with the first locale novel A/H1N1 influenza outbreak in China].

OBJECTIVE: To timely summarize past experience and to provide more pertinent reference for control and prevention in A/H1N1 cases in influenza season. METHODS: During May 25 to 31, 2009, 2 secondary community cases caused by a influenza A/H1N1 imported case. In the close contacts of 3 A/H1N1 cases, 14 had some aspirator symptoms onset, such as fever (> or = 37.5 degrees C), cough, sore throat and etc. Laboratory tests excluded the infection of A/H1N1 influenza. For throat swab test for the 14 cases, 7 were tested for seasonal influenza virus. A face-to-face or telephone interview was conducted by CDC staff to collect information of 62 close contacts. RESULTS: Of 14 fever cases, there was no significant by differences by age[15-age group: 19.2% (5/26), over 25-age group: 25.0% (9/36); chi(2) = 0.287, P = 0.592]; by sex group [24.0% (6/25) for male and 21.6% (8/37) for female; chi(2) = 0.048, P = 0.826], by working units [dressing and design, photograph, saleroom and others, consumer group: 42.1% (8/19), 27.3% (3/11), 12.5% (2/16) and 6.3% (1/16); chi(2) = 7.653, P = 0.054], by dormitory style [dormitory style = 33.3% (4/12), non-dormitory style = 29.4% (10/34); chi(2) = 0.699, P = 0.403]. All the cases had fever (37.5 - 37.9 degrees C), no case had diarrhea. One in 3 A/H1N1 cases had diarrhea. All the 14 cases were negative result for A/H1N1 RNA. Six from 7 cases were positive for seasonal influenza test. CONCLUSION: This was a seasonal influenza outbreak happened in the close contacts of first confirmed A/H1N1 cases in community in mainland China. It showed that we should exclude the seasonal influenza in the investigation of A/H1N1 cases in the seasonal influenza period in some time. It is necessary to take effective measure to strengthen the control and prevention of seasonal influenza.