Quantitative Assessment of Skull-Base Invasion in Nasopharyngeal Carcinoma Patients with Signal Intensity Index Based on Magnetic Resonance Imaging / 鼻咽癌杂志

Purpose: To evaluate the use of signal intensity index (SII) of skull-base invasion in nasopharyngeal carcinoma (NPC) using magnetic resonance imaging (MRI), select a best cut-off SII value to predict the outcome of NPC. Materials and Methods: One hundred and twenty-two NPC patients (92 men, 30 women) with skull-base invasion were included. All patients underwent MRI, signal intensities on T1-weighted imaging (T1WI) were measured for each invaded site and its contralateral normal counterpart. The SIIs were calculated, receiver operating characteristic curves were constructed. The optimal cut-off values were extracted. The overall survival (OS) rates of 5-year follow-up were performed. Results: Sensitivities for differentiating skull-base invasion from normal contralateral anatomy were 98.9%, 88.5% and 70.0%, and specificities were 98.9%, 96.0% and 74.4%, respectively. There were three cut-off values for differentiating invasion from normal anatomy of skull-base, 49%, 98%, and 60%. Significant difference in OS rates (84.2% vs. 57.1%, p=0.007) was seen for SII threshold values > 60% and those ≤ 60%. Conclusions: The SII might be a useful means of differentiating invasion from normal tissue at the skull-base in NPC. The cut-off value of quantitative SII at the skull-base may aid in monitoring the response to treatment of NPC patients.

Potential infections of H5N1 and H9N2 avian influenza do exist in Guangdong populations of China / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Southeast China is one of the sites of influenza origin. During 2003--2004, nine avian influenza outbreaks took place in Guangdong Province. But no human case was reported. To examine the status of potential human infection by human influenza (H1N1, H3N2) and avian influenza (H5N1, H7N7, H9N2) in the avian influenza epidemic area of Guangdong Province, China, we conducted a seroepidemiologic survey in the people of this area from April to June of 2004.</p><p><b>METHODS</b>Three out of 9 H5N1 avian influenza affected poultry areas in Guangdong were randomly selected, and the population living within 3 kilometers of the affected poultries were chosen as the survey subjects. One thousand two hundred and fourteen people were selected from 3 villages at random. Human and avian influenza antibody titers were determined by hemagglutination-inhibition (HI) test and microneutralization test (MNT).</p><p><b>RESULTS</b>The positive rate of antibody to H5N1 was 3.03% in the occupational exposure group and 2.34% in general citizens group; that of H9N2 was 9.52% in the occupational exposure group and 3.76% in the general citizens group. Moreover one case in the occupational exposure group was positive for H7N7. One year later, all previously positive cases had become negative except for one H5N1-positive case.</p><p><b>CONCLUSION</b>The observations imply that H5N1 and H9N2 avian influenza silent infections exist in Guangdong populations.</p>

Relationship between apoptosis and activity of protein kinase B in adrenocortical cells induced by cadmium chloride / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To study apoptosis induced by cadmium chloride (CdCl2) and the alteration in activity of protein kinase B (PKB/Akt) in adrenocortical cells.</p><p><b>METHODS</b>Fasciculata-glomerulosa (FG) cells of male guinea pigs were dispersed and primarily cultured in vitro. Features of apoptotic cells were observed using combined labeling with annexin-V and propidium iodide (PI) and flow cytometry. The activity of PKB/Akt was determined with immunoprecipitation and the chemiluminescence assay.</p><p><b>RESULTS</b>Apoptosis rate of FG cells increased with dose of CdCl2 two hours after treatment with 6.25-100.00 micromol/L of it, with significant difference in the groups treated with 25.00, 50.00, 100.00, micromol/L of CdCl2, as compared with the control group (P < 0.01). Regression analysis showed that occurrence of apoptosis correlated with the dose of CdCl2 in a dose-response pattern. In the meanwhile, there were obviously elevated percentages of apoptotic cells as the increase in duration of incubation ranging from 5.58% to 73.08% for incubating cells with 50.00 micromol/L of CdCl2, from 15 minutes to 4 hours. Duration of incubating cells with CdCl2 were correlated with occurrence of apoptosis in a time-effect manner. The gray scales of PKB/Akt were manifested to be decreased as the ascending of CdCl2 dosage from 6.25 to 200.00 micromol/L, with the linear correlation.</p><p><b>CONCLUSION</b>6.25 to 100.00 micromol/L CdCl2 might elicit apoptosis of adrenocortical cells. Meanwhile, PKB/Akt is decreased.</p>

Study on the impact of related psychological stress and fatigue to different smoking behaviors among undergraduate students / 中华流行病学杂志

<p><b>OBJECTIVE</b>To explore the relationship between psychological stress, fatigue and different smoking behaviors among undergraduate students.</p><p><b>METHODS</b>8138 undergraduate students in grade 1 to 3 were sampled with cluster sampling method from a comprehensive university in Guangzhou, and were studied on their psychological stress, peer and self smoking behaviors, as well as socio-demographic factors with a self-administered questionnaire. Physical and mental fatigue was measured by Chalder fatigue scale. A multinomial logistic regression analysis was performed to explore the association between psychological stress, fatigue and different smoking behaviors with 'non-smokers' defined as control group while 'triers' and 'current smokers' as case group, respectively.</p><p><b>RESULTS</b>There were students trying to smoke or becoming current smokers on university campus. After adjusting the effect of relevant socio-demographic factors and peer smoking behavior, physical fatigue (OR = 1.044, 95% CI: 1.013-1.075) and 'worry about current academic and future work' (OR = 1.020, 95% CI: 1.001-1.040) were the risk factors of trying to smoke among male students, while 'study stress (OR = 1.063,95% CI: 1.012-1.117) was the risk factor for female students when start smoking. 'Personnel relationship and environment stress' (OR = 1.152, 95% CI: 1.012-1.312) were the risk factors for female students' current smoking behavior.</p><p><b>CONCLUSION</b>Psychological stress and fatigue were moderately associated with smoking behavior among undergraduate students and the impact was different on different gender and smoking behaviors that suggesting that some specific psychological measures should be taken so as to control different smoking behaviors among undergraduate students.</p>

Process evaluation on a health promotion model regarding smoking prevention among Chinese secondary school students / 中华流行病学杂志

<p><b>OBJECTIVE</b>To evaluate the process of smoking prevention and control among Chinese adolescent with a model on health promotion in junior high school.</p><p><b>METHODS</b>A cluster-randomized, controlled and schooled-based trial on smoking prevention was conducted among 2343 students at four secondary schools in Huangpu District of Guangzhou. Students 'reports and investigators' daily records were used to evaluate the intervention measures.</p><p><b>RESULTS</b>During the one-year period of intervention (Dec. 2004 through Dec. 2005), eighteen activities had been implemented among students, teachers, parents and cigarette retailers. Ranked by the rate of awareness, the top six activities were shown as follows: "the nicotine toxicity experiment" (90.7%), "agreement of building families free of smoking"(77.7%), "a letter to parents" (77.1%), "no-smoking signs" (76.5%), "Blackboard information about health and smoking" (75.0%), and "signature on the 18th World Day of No Smoking" (70.2%). Among all the activities, "the nicotine toxicity experiment" had the highest rate of participation (88.5%), followed by "a letter to parents" (73.6%), "agreement of building families free of smoking" (69.8%), "health education through experiments"(68.6%), "health education through multimedia" (65.7%) and "signature on the 18th World Day of No Smoking" (65.6%). The top seven activities in which students showed greatest interests were "the nicotine toxicity experiment" (64.5%), "signature on the 18th World Day of No Smoking" (33.0%), "health education through experiments" (31.2%), "health education through multimedia" (29.8%), "class meetings with a thesis of smoking" (26.8%), "health pamphlets" (26.6%), "specific textbooks" (25.9%). The extent of students' general satisfaction to the work of tobacco control in school during the last year was 52.4%. The biggest perceived shortcoming for the intervention plan was the low participation of students.</p><p><b>CONCLUSION</b>Some intervention measures had not been fully carried out among the students and only covered part of them. It is necessary to adjust the previous intervention measures through keeping the nicotine toxicity experiment, health education through multimedia and other measures with extensive participation of students and at the same time, to avoid literal materials, exhibition boards and traditional single-way health education program.</p>

Analysis on factors influencing the smoking behaviors among male secondary school students under the structural equation model / 中华流行病学杂志

<p><b>OBJECTIVE</b>To analyze the direct and indirect outcomes of influencing factors on smoking behaviors among adolescents.</p><p><b>METHODS</b>Self-administered questionnaires were used to collect smoking-related information from 2021 respondents. Measurement models were built by confirmatory factor analysis and parameters were estimated by ERLS method. The final structural equation model was determined by comprehensive evaluation and necessary modification.</p><p><b>RESULTS</b>Three latent variables were extracted from 10 manifest variables of environment, while only one latent variable was identified from 9 manifest variables of attitudes. The goodness of fit for the structural equation model was satisfactory that all indices had met corresponding requirements. The final model could explain 38.8% of the variance of smoking behaviors. Four factors (smoking environment, smoking restriction from parents and teachers, determination of cigarette refusal and attitudes toward smoking) were directly affecting the smoking behaviors, while another three factors (grade, health knowledge and school environment) had indirect impacts. According to the percentages of their contribution, the risk factors were ranked as follows: smoking environment (45.76%), attitudes toward smoking (19.88%) and grade at school (0.44%). Similarly, the top protective factor were: determination of cigarette refusal (16.61%), followed by smoking restriction from parents and teachers (10.51%), health knowledge (3.89%) and school environment (2.92%).</p><p><b>CONCLUSIONS</b>Heath knowledge had minor effect on smoking in adolescents but could indirectly affect their smoking behaviors through changing their belief. Grade at school had a doubled influence on smoking, but mainly served as a risk factor. Tobacco control measures for adolescents should not only be limited to health education but environment factors as well.</p>

Study on the related factors of smoking behavior transition at different stages among undergraduate students / 中华流行病学杂志

<p><b>OBJECTIVE</b>To explore the influencing factors of smoking behavior transition at different stage of smoking among undergraduate students.</p><p><b>METHODS</b>8138 undergraduate students from grade 1 to 3 were selected using cluster sampling method from an university in Guangzhou with their smoking behaviors and relevant factors studied through a self-administered questionnaire. Beginners, un-regular smokers and regular smokers were defined as "case group", while non-smokers, beginners and un-regular smokers were defined as "control group" accordingly. Three multivariable logistic regressions were separately conducted to explore the influencing factors of behavioral transition at different stage of smoking.</p><p><b>RESULTS</b>Of the 8138 students investigated, the prevalence rates of beginners, un-regular smokers and regular smokers were 19.6%, 2.0% and 1.1%, respectively; while all of the above said three rates increased with grades of the students. Some students might still try to smoke or become regular smoker in the university. In male undergraduate students, determinants for the transition from non-smokers to s mokers were: source of students, father' s educational level, smoking-related knowledge and belief, and smoking habit of the roommates. Risks that influencing the transition from beginners to un-regular smokers were: being non-medical students,smoking-related belief, roommates and classmates who were smokers and transition from un-regular smokers to regular smokers would include father' s educational level and average income of family. In female undergraduate students,influencing factors from non-smokers to beginners were mother's educational level, smoking-related belief, and roommates smokers, while father's educational level, roommates and classmates' smoking habits were significant associated with beginners' change to un-regular smokers.</p><p><b>CONCLUSION</b>The influencing factors related to the transition of different stage on smoking would be different in undergraduate students,and some specific measures should be taken based on the different stage of smoking.</p>