Pathogenic spectrum of enteroviruses associated with hand, foot and mouth disease by a GeXP™-based multiplex reverse transcription-PCR assay in Jinan, China, 2009-2012 / 病毒学报

We investigated the pathogenic spectrum of enteroviruses associated with hand, foot and mouth disease (HFMD) in Jinan, China. A total of 274 specimens with a clinical diagnosis of HFMD in Jinan from 2009 to June 2012 were used. A GenomeLab™ (GeXP)-based multiplex reverse transcription-polymerase chain reaction (RT-PCR) assay was employed to simultaneously detect 15 serotypes of human enteroviruses: human enterovirus (EV)71; coxsackievirus A (CVA)16, 4, 5, 6, 9, and 10; CVB1, 3 and 5; echovirus (Echo) 6, 7, 11, 13 and 19. Results showed that all samples were enterovirus-positive, with the most common serotypes being EV71 (25.18%) and CVA16 (16.06%), followed by CVA10 (14.23%), CVA6 (7.30%), CVB1 (1.09%), Echo6 (0.73%), CVA9 (0.36%), CVB3 (0.36%) and co-infections (5.11%). CVA10 and CVA6 had the third and fourth highest prevalence of pathogens for HFMD, respec- tively. The most prevalent season for CVA10 was from April to August, with a peak in April; for CVA6 it was from April to August, with a peak in June. This is the first report of the pathogenic spectrum of en- teroviruses associated with HFMD in Jinan using the GeXP-based multiplex RT-PCR assay. These data will provide the scientific evidence for the prevention and control of epidemics, as well as therapy for HFMD patients.

Effect of occupational combined exposure of chromium and iron on erythrocyte metabolism / 中华预防医学杂志

<p><b>OBJECTIVE</b>To investigate the effect of combined occupational exposure of chromium and iron on erythrocyte metabolism, and the possible mechanism.</p><p><b>METHODS</b>A total of 115 chromate production workers were selected in a chemical factory of Jinan as exposure group, Dec, 2008, and 60 healthy residents from a community which was far away from the factory were enrolled as control group. Environmental concentrations of chromium and iron were collected by filter membrane sampling and determined. The peripheral blood of subjects were collected for determination of chromium, iron, copper in whole blood and folate, vitamin B₁₂ in serum, mean corpuscular hemoglobin (MCH) and mean corpuscular volume (MCV) and correlation analysis was conducted.</p><p><b>RESULTS</b>The median (quartile interval) concentration of air-chromium and air-iron in workplace were 9.0 (10.5) and 11.2 (10.1) µg/m³, respectively, which were significantly higher than that of the control (0.1 (0.1) and 7.2 (2.5) µg/m³) (all P values < 0.01). Blood-chromium and blood-iron of the exposed group were 15.5 (14.1) µg/L and (895.1 ± 90.2) mg/L, which were significantly higher than the counterpart of the control (3.6(2.0) µg/L, (563.7 ± 49.3) mg/L) (all P values < 0.01). Serum folate ((6.9 ± 2.5) µg/L), serum vitamin B₁₂ ((396.4 ± 177.0) µg/L) and blood copper ((777.6 ± 103.5) µg/L) of the exposed group were all significantly lower comparing to the control group ((558.0 ± 330.8), (8.1 ± 3.8), (812.1 ± 94.6) µg/L) (all P values < 0.05). The relationships between blood chromium and serum folate, serum vitamin B₁₂ were statistical significant (r = -0.319 and -0.293, P < 0.01). Both serum vitamin B₁₂ and blood copper correlated with mean corpuscular hemoglobin (MCH) and mean corpuscular volume (MCV) (r = -0.223, -0.242, -0.261, -0.292, all P values < 0.01).</p><p><b>CONCLUSION</b>Combined chromium and iron exposure existed in the workplace. Adverse effect of Chromium on human erythrocyte may via folate and vitamin B₁₂ metabolism, while iron may via copper metabolism.</p>

The effects of occupational soluble chromate exposure on immunological function of T-cell / 中华预防医学杂志

<p><b>OBJECTIVE</b>To investigate the early changes of some immunological function of T-cell in chromate workers.</p><p><b>METHODS</b>A total of 115 workers exposed to different levels of soluble chromate were enrolled in exposed group; while 90 non-exposure workers who lived far away from the chromate plant were enrolled as control. The air concentration of soluble chromate was determined by atomic absorption spectrometry. CD3(+), CD3(+)CD4(+), CD3(+)CD8(+) and CD4(+)/CD8(+) of T-cell were determined by flow cytometry analysis.</p><p><b>RESULTS</b>The individual air chromate concentration in the exposed group was (27.51 +/- 33.25) microg/m(3), and the control group was (0.16 +/- 0.15) microg/m(3). The significant difference between the two groups was observed (z = 8.045, P < 0.01). The levels of the lymphocyte subsets (CD3(+), CD3(+)CD4(+), CD3(+)CD8(+) and CD4(+)/CD8(+)) in exposed group were (30.08 +/- 17.75)%, (1.04 +/- 1.73)%, (11.94 +/- 9.78)%, 0.10 +/- 0.14. While, those of control group were (63.00 +/- 13.57)%, (30.51 +/- 5.16)%, (14.82 +/- 4.59)%, 2.17 +/- 0.53, higher than that of the exposed group (z values were 4.484, 5.227, 1.976, -5.218, respectively, P < 0.05).</p><p><b>CONCLUSION</b>On the basis of individual air monitoring, the cellular immune function affected by soluble chromate is mainly based on T lymphocyte inhibition. The indicators CD3(+)CD4(+) mentioned above may be considered as efficient biomarkers in further research.</p>

The effect of inhalable titanium dioxide on the oxidative stress among occupational population / 中华预防医学杂志

<p><b>OBJECTIVE</b>To investigate the inhalable titanium dioxide exposure level and make an assessment of its oxidative effect on occupational exposed population.</p><p><b>METHODS</b>A total of 7 workers occupationally exposing to inhalable titanium dioxide were recruited into the study. The basic information and occupational history were collected by interview, while their blood sample (10 ml for each subject) were collected before and after the investigation, respectively. Pre- and post-work shift urine samples (60 ml for each subject) were collected for 29 days consecutively. The daily personal titanium dioxide exposure level, temperature and relative humidity were detected too. Urinary 8-hydroxy-deoxyguanosine (8-OHdG) and serum high-sensitivity C-reactive protein (hs-CRP) were detected by ELISA and latex immunoturbidimetric assay, respectively.</p><p><b>RESULTS</b>The mean concentration of air inhalable titanium dioxide was (1.194 ± 1.015) mg/m(3). Serum hs-CRP level before and after the investigation was (1.13 ± 1.08), (1.33 ± 1.01) mg/L, respectively. No statistical significance was observed between hs-CRP level before and after the investigation (t = -0.848, P = 0.425). Pre- and post-work shift urinary 8-OHdG was (3.51 ± 1.39), (3.65 ± 1.06) µmol/mol Cr, respectively. A positive correlation was found between the concentration of inhalable titanium dioxide and the changes of 8-OHdG level (r = 0.192, t = 2.09, P = 0.039). Linear mixed-effect models, adjusted by work shift, years of employment, age, body mass index, smoking status, temperature and relative humidity, showed no significant exposure-respond trend between the inhalable titanium dioxide concentration and 8-OHdG level (β = 0.288, t = 1.940, P = 0.055).</p><p><b>CONCLUSION</b>Our findings do not support the potential link between occupationally exposure to inhalable titanium dioxide and high induction of DNA oxidative stress.</p>

Levels of transition on maternal transferred measles antibody in infants in 3 cities in China / 中华流行病学杂志

Objective To understand the epidemiological characteristics of age distribution of measles and related policies on measles vaccines (live; MV) in infants through analyzing the antibody levels of comparison in maternal-infant pairs. Transition of immunity in infants was also studied to provide theoretic basis for measles immunization strategy and to reduce the incidence of month-old infants. Methods In cities of Ningbo, Harbin, and Jinan from Zhejiang, Heilongiiang and Shandong provinces, data was collected from 2004 to 2007 and analyzed regarding the epidemic situation of measles. Studies on maternal-transferred measles antibody were carried our sero-epidemiologically. Results Most of the measles cases were found among babies younger than 12 months,and the incidence of < 1 year olds had been increasing.The distribution was dominated by 5-8 month olds in infant measles cases. The positive rate and GRMT of measles antibody in newborns were 89.3 percent and 738.93. The positive rate of the measles antibody and GMRT of the 6-month infant were 6.9 % and 6.89, while 6.7 % and 3.69 in 8-month infant. There wasa declining trend of the positive rate of the measles antibody during the newborns to 8-month infant. The positive rate and GRMT of measles antibody in mothers were 84.3 percent and 516.94. Mother's measles antibodies mainly to be at low and moderate level, which accounted for 50.4 percent and 30.3 percent respectively, the correlation coefficient between mother and infant was 0. 840. Conclusion Maternal-transferred measles antibody decreased as the growth of infants. The positive rates of measles antibody were quite low in 6-month and 8-month olds which were the age range that needs most attention.

The correlation between personal occupational exposure to soluble chromate and urinary chromium content / 中华预防医学杂志

<p><b>OBJECTIVE</b>To explore and provide the possible biological limit of urinary chromium for population occupationally exposure to soluble chromate, as to providing scientific evidences for health monitoring and risk assessment.</p><p><b>METHODS</b>A cross-sectional study was conducted. The studied population contained 83 workers from different processes of the chromate plant, in addition, 10 farmers without exposure to chromate matched with exposed subjects by age, gender and smoking status were identified as a control group. The air chromium concentration for personal exposure during 8-hours shift and the urinary chromium concentration post-shift were determined and their relationship was analyzed statistically. Meanwhile, the literatures of the biological limit of urinary chromium for occupational exposure to soluble chromate were studied.</p><p><b>RESULTS</b>For the control group, the air chromium concentration had a range from 0.00 microg/m(3) to 0.08 microg/m(3) and the urinary chromium concentration from 0.40 microg/g Cre to 1.02 microg/g Cre. For the exposure group, the air chromium concentration was from 0.10 microg/m(3) to 287.00 microg/m(3) and the urinary chromium concentration was from 1.14 microg/g Cre to 79.07 microg/g Cre. The positive relationship existed in between air chromium concentration and urinary concentration. The urinary chromium concentration was increased depending on the chromate exposed level. The regress equation was that Urinary chromium concentration (microg/g Cre) = 4.16 + 236.86 x air concentration for chromate (mg/m(3)), r = 0.976. The recommendation of ACGIH (USA, 2004) was 65.1 micromol/mol Cre (30 microg/g Cre) with the same TLV-TWA of 0.05 mg/m(3) as our National standard about the air chromate concentration.</p><p><b>CONCLUSION</b>Our findings suggested that the post-shift urinary chromium concentration might be used as an exposed biomarker for chromate. Considering the recommendation of ACGIH (USA, 2004) and the feasibility of the standard performed, we suggest that the biological threshold limit of urinary chromium for occupational exposure to soluble chromate in China should be 65.1 micromol/mol Cre (30 microg/g Cre) (post-shift urine for consecutive 5 work days.).</p>

Chromium content in erythrocytes serving as the exposure biomarker for workers exposed to soluble chromate / 中华预防医学杂志

<p><b>OBJECTIVE</b>To explore biological exposure markers, we investigated the chromium content in peripheral erythrocytes from occupational population with broad ranges of soluble chromate exposure, as the candidate biomarker may provide the scientific evidence for health risk assessment in occupational chromate-exposed population.</p><p><b>METHODS</b>A cross-sectional study was conducted in chromate exposed workers employed at a chromate factory in a district of Jinan city, Shandong Province. The studied population contained 114 workers from different processes of the chromate plants, which included 74 males and 40 females, with an age range from 25 to 52 years old, averaging at (35.83 +/- 6.14) years old; the length of service was ranging from 1 year to 37 years, an average of (14.20 +/- 6.77) years. In addition, 30 farmers in the countryside one hundred kilometers away from the factory, without exposure to chromate matched with exposed subjects by age, gender and smoking status were identified as a control group, which included 22 men and 8 women, with age ranging from 25 years old to 47 years old, having an average age of (36.13 +/- 6.17) years old. Personal information on age, chromate exposure, medical history, smoking habit and alcohol consumption was obtained at an interview. The air concentration of personal exposure was determined by individual sampling for 8 hours per day as shift work, and chromium was assayed by atomic absorption spectrometry. The chromium content in the erythrocytes from peripheral blood was determined by graphite furnace atomic absorption spectrometry. The potential plasma reduction capacity was determined by dibenzene anthracoamid dihydrazide spectrophotometry. The content of total vitamin C and reductive ascorbic acid were determined by 2, 4-dinitrobenzene hydrazine. The data were analyzed by SPSS10.0 software for statistical significance.</p><p><b>RESULTS</b>(1) The results showed that the chromium levels in erythrocytes in the exposed group [(15.79 +/- 31.01) microg/L] were significantly higher than those in the control group [(3.21 +/- 2.20) microg/L] (P < 0.01). (2) There existed a dose-response relationship between the personal airborne chromate concentration and the chromium content in erythrocytes. As airborne chromate concentration lowered to 106.00 microg/m(3), the chromium content in erythrocytes increased, depending on the air concentration of chromate. (3) Correlation analysis showed that there was a significant positive correlation between airborne chromate concentration and the chromium content in erythrocytes (P < 0.01). (4) In multiple regression analysis, it was found that the potential plasma reduction capacity and reductive ascorbic acid may be a good indicator for oxidative stress produced by chromate exposure and be used to evaluate the effects on intracellular uptake of chromium (VI).</p><p><b>CONCLUSION</b>Our findings suggested that the chromium content in erythrocytes should be used as an effective exposed biomarker in the risk assessment for occupational chromate-exposure.</p>

Study on DNA strand breaks in workers exposed to soluble chromate / 中华预防医学杂志

<p><b>OBJECTIVE</b>To explore the biological effective markers, we investigated DNA strand breaks in peripheral lymphocytes from occupational population with broad ranges of soluble chromate exposure.</p><p><b>METHODS</b>We conducted a cross-sectional study in the chromate exposed workers employed at a chromate factory in a district of Jinan, Shandong Province. The studied population contained 114 workers from different processes of the chromate plants, in addition, 30 farmers in the countryside about one hundred kilometers away from the factory, without exposure to chromate were matched with the exposed subjects by age, gender and smoking status being identified as a control group. Personal information on age, chromate exposure, medical history (including acute infection and medicine usage), smoking habit and alcohol consumption was obtained by questionnaire. DNA strand breaks in lymphocytes were detected by single-cell gel electrophoresis assay (comet assay) and the DNA damaged degree was evaluated by the score weighted by comet type. The air concentration of chromate was determined by individual sampling for 8 hours per day as shift work and chromium was assayed by atomic absorption spectrometry. The chromium content in the erythrocytes from peripheral blood was determined by graphite furnace atomic absorption spectrometry. The data were analyzed by SPSS10.0 software for statistical significance.</p><p><b>RESULTS</b>(1) The results showed that the score for DNA strand breaks in lymphocytes were 54.52 +/- 23.51 in the exposed group, which was significantly higher than those in the control group (24.70 +/- 11.84) (P < 0.01). (2) The degree of DNA strand breaks in lymphocytes was increased in a dose-dependent manner ranging from 0 microg/m(3) to 106.00 microg/m(3). (3) Correlation analysis showed that there was a significant positive correlation between airborne chromate concentration and the degree of DNA strand break in lymphocytes (P < 0.01). (4) By multiple regression analysis, it was found that the airborne concentrations, chromium contents in red blood cells and smoking habits were factors which might affect the degree of DNA breaks.</p><p><b>CONCLUSION</b>Our findings suggest that DNA strand break in lymphocytes should be an effective biomarker for occupational chromate-exposed population and be applied in biological monitoring and health risk assessment for occupational chromate-exposed population.</p>