Cyclooxygenase-1 Regulates the Development of Follicular Th Cells via Prostaglandin E2.

Cyclooxygenase (COX)-1, one of the critical enzymes required for the conversion of arachidonic acid to PGs, has been demonstrated to play an important role not only in the cardiovascular system but also in the immune system. COX-1 has been found to regulate early B cell differentiation, germinal center formation, and Ab production of B cells. However, the underlying mechanisms of COX-1-mediated B cell activation remains not fully understood. In this study, we reported that COX-1 is a potential regulator for the development of follicular Th (TFH) cells. COX-1-deficient (COX-1-/- ) mice displayed a significant reduction of TFH cells upon influenza infection or immunization with keyhole limpet hemocyanin, which led to a severe impairment of germinal center responses. We further demonstrated that COX-1-derived PGE2, via binding with its receptors EP2/EP4, represents the underlying mechanism. The administration of EP2/EP4 agonists or PGE2 almost completely rescued the defective TFH cell generation in COX-1-/- mice. Taken together, our observations indicate that COX-1 plays an important role in the development of TFH cells.

An Epistaxis Emergency Associated with Multiple Pollutants in Elementary Students.

Emergencies of epistaxis in students caused by environmental pollution have rarely been reported to date. This study aimed to explore the cause of an emergency of epistaxis in elementary students by using a field epidemiological investigation. Twenty-two epistaxis cases from a single school with differences in gender, age, and classroom, were diagnosed within a period of 7 days. The air concentration of chromic acid mist (Cr6+) in the electroplating factory area, new campus, and residential area exceeded the limit of uncontrolled emissions. The emission of HCL and H2SO4 was also observed. Formaldehyde levels in the classrooms exceeded the limits of indoor air quality. Abnormal nasal mucosa was significantly more frequent in the case group (93.3%) and control group 1 (of the same school) (66.7%) than in control group 2 (from a mountainous area with no industrial zone) (34.8%; P < 0.05 and P < 0.01, respectively). On the basis of the pre-existing local nasal mucosal lesions, excessive chromic acid mist in the school's surrounding areas and formaldehyde in the classrooms were considered to have acutely irritated the nasal mucosa, causing epistaxis. Several lessons regarding factory site selection, eradication of chemical emissions, and indoor air quality in newly decorated classrooms, should be learned from this emergency.

[Survey on individual occupational health protection behaviors of welding workers using theory of reasoned action].

OBJECTIVE: To apply theory of reasoned action at survey on welding workers occupational health protection behaviors and explore related influencing factors. METHODS: nine companies were randomly selected from areas with many welding works in Zhejiang Province. All welding workers were surveyed using a questionnaire based on theory of reasoned action. RESULTS: 10.06%, 26.80% and 37.50% of the respondents never or seldom used eyeshade, mask and earplug, respectively. After controlling the socio-demographic factors, welding workers' behavioral belief was correlated with the behaviors of eyeshade-mask and earplug use (χ(2) = 31.88, 18.77 and 37.77, P < 0.01). the subjective norm of company was correlated with all protection behaviors (χ(2) = 20.60, 10.98 and 19.86, P < 0.01), the subjective norm of colleague was correlated with mask and earplug use, (χ(2) = 27.43, 36.39, P < 0.01), and the subjective norm of family was correlated with mask use (χ(2) = 5.73, P < 0.05). CONCLUSION: Theory of reasoned action is suitable for welding worker occupational health related behaviors. It is useful to improve occupational health education, to effectively select health education objective and to tailor health education contents.

[Analysis of new pneumoconiosis cases during 2006-2009 in Zhejiang province].

OBJECTIVE: To analyze the characteristics of pneumoconiosis cases in Zhejiang province and to provide the evidence for pneumoconiosis control and prevention measures in Zhejiang province. METHODS: The data of new pneumoconiosis cases were from national surveillance system of occupational disease in Zhejiang province during 2006-2009, and were analyzed for distribution, age, exposure duration, pneumoconiosis phases and enterprise types. RESULTS: During 2006-2009, 819 new pneumoconiosis cases (173, 157, 209 and 280 cases, respectively) were reported, 86.9% cases suffered from silicosis. Most of pneumoconiosis cases were distributed in Ningbo, Wenzhou areas and in building materials, machinery, coal, geological and mining, light industries and construction enterprise. The average ages of new pneumoconiosis cases were (47.8 +/- 10.0), (52.5 +/- 13.1), (55.5 +/- 11.2) and (55.9 +/- 12.2) years old, respectively and showed a significant increase trend (P<0.05). The average exposure duration of new pneumoconiosis cases were (12.4 +/- 8.6), (12.9 +/- 9.4), (12.4 +/- 8.6) and (15.7 +/- 10.0) years. The average exposure duration of phase I, phase II, phase III new pneumoconiosis cases were (14.3 +/- 9.87), (12.4 +/- 8.7) and (11.4 +/- 7.1) years, respectively and there were significant differences (P<0.05). CONCLUSION: New pneumoconiosis cases in Zhejiang province are increasing year by year, the main type of pneumoconiosis is silicosis, the distribution of pneumoconiosis cases is associated with the areas and enterprises, and the exposure duration of new pneumoconiosis cases is relatively shorter.

[Photocatalytic degradation of reactive red X-3B by immobilized P25 in a contact oxidation reactor].

The immobilized photocatalyst, P25 supported by glass fiber, was prepared by calcining method. The effect of calcining temperature on the photocatalytic activity and the effect of initial pH and inorganic anions on the photocatalytic degradation of Reactive Red X-3B were explored in a new photocatalytic contact oxidation reactor. The results show that catalyst activity is affected drastically by calcining temperature, the optimal temperature is 300 degrees C; the SEM photos of immobilized catalyst indicated that P25 adhered to glass fiber firmly; The Reactive Red X-3B was more easily degraded in acid solution, when initial pH increasing from 2.0 to 10.0, the degradation rate of Reactive Red X-3B decreased from 90.06% to 42.71%; inorganic anions, CO3(2-) and SO4(2-), had little effect on the degradation of Reactive Red X-3B. However, the degradation of Reactive Red X-3B significantly decreased, 17.03% down, in the presence of Cl-. So it was a good alternate scenario to conduct photocatalytic oxidation by using immobilized P25 in a contact oxidation reactor.