Evaluation of intake fractions for different subpopulations due to primary fine particulate matter (PM2.5) emitted from domestic wood combustion and traffic in Finland

Domestic wood combustion and traffic are the two most significant primary fine particulate matter (PM_2.5) emission source categories in Finland. We estimated emission–exposure relationships for primary PM_2.5 emissions from these source categories using intake fractions (iF), which describes the fraction of an emission that is ultimately inhaled by a target population. The iFs were calculated for four different emission source subcategories in Finland in 2000: (1) domestic wood combustion in residential buildings, (2) domestic wood combustion in recreational buildings, (3) traffic exhaust and wear emissions, and (4) traffic resuspension emissions. The iFs were estimated for both total population and for subpopulations with different gender, age, and educational status. Primary PM_2.5 emissions were based on the Finnish Regional Emission Scenario model and the dispersion of particles was calculated using the Urban Dispersion Modeling system of Finnish Meteorological Institute. Both emissions and dispersion were estimated on a 1 km spatial resolution. The iFs for primary PM_2.5 emissions from (1) residential and (2) recreational buildings were 3.4 and 0.6 per million, respectively. The corresponding iF for (3) traffic exhaust and wear and (4) traffic resuspension emissions were 9.7 and 9.5 per million, respectively. The differences in population-weighted outdoor concentrations were significant between subpopulations with different educational status so that people with higher education were exposed more to traffic-related PM_2.5.     

Follow-up study of cancer incidence after chlorophenol exposure in a community in southern Finland

OBJECTIVES: In the 1970s and 1980s, people in a village in southern Finland had been exposed to high concentrations of chlorophenols in the drinking water and in fish from a nearby lake. An ecological analysis and a case-control study conducted around 1990 indicated significant excess in the incidence of non-Hodgkin's lymphoma and soft-tissue cancer in the municipality and a relationship between the chlorophenol exposure and the incidence of these cancers. The present article reports a follow-up of cancer risk in the same study area during a 20-year period after the closing of the old water intake plant, which was contaminated by chlorophenols. METHODS: The observed and expected numbers of cancer were obtained for three periods, 1953-1971 (before exposure), 1972-1986 (during exposure) and 1987-2006 (after exposure), for all cancers combined and separately for cancers potentially related to chlorophenols. RESULTS: The present study demonstrates that all of the cancer risks returned to the average population level during the 20-year period after the old water intake plant was closed and chlorophenol exposure stopped. CONCLUSIONS: The rapid changes in cancer risk after changes in chlorophenol exposure suggest that chlorophenols may have a promotion effect in the carcinogenic process.     

Iron supplement in pregnancy and development of gestational diabetes—a randomised placebo-controlled trial

Objective  To test the hypothesis that iron supplement from early pregnancy would increase the risk of gestational diabetes mellitus (GDM).
Design  Randomised placebo-controlled trial.
Setting  A university teaching hospital in Hong Kong.
Population  One thousand one hundred sixty-four women with singleton pregnancy at less than 16 weeks of gestation with haemoglobin (Hb) level between 8 and 14 g/dl and no pre-existing diabetes or haemoglobinopathies.
Methods  Women were randomly allocated to receive 60 mg of iron supplement daily ( n = 565) or placebo ( n = 599). Oral glucose tolerance tests (OGTTs) were performed at 28 and 36 weeks. Women were followed up until delivery.
Outcome measures  The primary outcome was development of GDM at 28 weeks. The secondary outcomes were 2-hour post-OGTT glucose levels, development of GDM at 36 weeks and delivery and infant outcomes.
Results  There was no significant difference in the incidence of GDM in the iron supplement and placebo groups at 28 weeks (OR: 1.04, 95% confidence interval [CI]: 0.7–1.53 at 90% power) or 36 weeks. Maternal Hb and ferritin levels were higher in the iron supplement group at delivery ( P < 0.001 and P = 0.003, respectively). Elective caesarean section rate was lower in the iron supplement group (OR: 0.58, 95% CI: 0.37–0.89). Infant birthweight was heavier ( P = 0.001), and there were fewer small-for-gestational-age babies in the iron supplement group (OR: 0.46, 95% CI: 0.24–0.85).
Conclusion  Iron supplement from early pregnancy does not increase the risk of GDM. It may have benefits in terms of pregnancy outcomes.     

Validation of a prognostic scoring system for locally recurrent nasopharyngeal carcinoma treated by stereotactic radiosurgery

Background  

Selection of patients with local failure of nasopharyngeal carcinoma (NPC) for appropriate type of salvage treatment can be difficult due to the lack of data on comparative efficacy of different salvage treatments. The purpose of the present study was to validate a previously published prognostic scoring system for local failures of NPC treated by radiosurgery based on reported results in the literature.     

Comparison of single versus fractionated dose of stereotactic radiotherapy for salvaging local failures of nasopharyngeal carcinoma: a matched-cohort analysis

Background

Oral submucous fibrosis is a common oral health problem in India. This study was conducted to correlate the histopathological diagnosis with habits and clinical findings in patients suffering from oral submucous fibrosis (OSF).

Methods

Patients suffering from oral submucous fibrosis from the Departments of Otorhinolayngology and Pathology, Moti Lal Nehru Medical College, Allahabad, India were studied from 2004–2008. Detailed information was gathered in a pretested proforma. Emphasis was given to the various addictions, clinical findings and histological examination was done.

Results

Two hundred and thirty nine patients were studied, yielding a male to female ratio of 6.8:1. Maximum patients were in the 21–30 years age group with a marked male predominance. Of these, 197 (82.4%) patients chewed areca nut/dohra, 14 (5.8%) were smokers and 2 (0.8%) patients were habituated to alcohol. 89(37.2%) patients reported difficulty in opening of the mouth (trismus). 51 (57.4%) patients were found to have stage II (2–3 cm) trismus while rest had stage I and III. The buccal mucosa was found to be the most commonly involved site. On the basis of histopathological examination, 52(21.7%) were classified as OSF grade I, 75(31.3%) patients as grade II and 112(46.8%) had grade III disease.

Conclusion

The widespread habit of chewing dohra/paan masala is a major risk factor of OSF, especially in the younger age group. In this study, an increase in histopathological grading was found with severity and duration of addiction habit. However no significant correlation was found between clinical staging and histopathological grading.     

RP-HPLC测定立复欣注射液的含量

目的：建立一种快速简便的反相HPLC法测定立复欣注射液的含量,同时考察25度立复欣注射液在5％GS,0．9％NS和10％GNS中的稳定性,方法：采用Lichrospher 100(RP-8.5um*250mm)柱,以甲醇－乙腈－0．04M KH2PO4溶液（31．5：31．5：37）为流动相,流速1ml/min,柱温40度,254nm柴外检测;观察溶液的外观并用酸度计测定其PH值,结果：回收率为100．5：37）为流动相,流速1ml/min,柱温40度,254nm紫外检测,观察溶液的外观并用酸度计测定其PH值,结果：回收率为100．87％,RSD＝1．4％（n=5),在4－120mg/l范围内,峰面积对浓度呈良好的线性关系,r=0\99989,25度下样品在输液中的PH值,含量及颜色在0－6h内均无明显变化。结论：本法简速,灵敏底高,准确性好;25度,6h内样 在上述输液中稳定性好。     

Comparative Acute Lethality of 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD), 1,2,3,7,8-Pentachlorodibenzo-p-dioxin and 1,2,3,4,7,8-Hexachlorodibenzo-p-dioxin in the Most TCDD-Susceptible and the Most TCDD-Resistant Rat Strain

We have previously demonstrated a more than 300-fold difference in acute LD50 values for 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) between male Long-Evans (Turku AB; L-E) and Han/Wistar (Kuopio; H/W) rats after intraperitoneal exposure. In the present study, we compared the acute lethality of TCDD, 1,2,3,7,8-pentachlorodibenzo-p-dioxin (PCDD) and 1,2,3,4,7,8-hexachlorodibenzo-p-dioxin (HCDD) in these strains by intragastric administration. In agreement with previous data, H/W rats proved to be strikingly resistant to TCDD, since even the highest dose tested, 7200 μg/kg, was below the LD50 level for both genders. The corresponding LD50 values for female and male L-E rats were 9.8 and 17.7 μg/kg, respectively. A similar strain difference was discovered for PCDD: the LD50 value was > 1620 μg/kg for female H/W rats and between 20 and 60 μg/kg for female L-E rats. Surprisingly, the acute lethality of HCDD did not follow the same pattern. Female H/W rats turned out to be only about 10 times less susceptible to that congener than female L-E rats (LD50 values 1871 and between 120 and 360 μg/kg, respectively). These findings do not support the widely accepted concept that sufficiently high doses of all dioxin congeners will produce the same effects. Either the higher chlorinated dioxins have toxic effects distinct from those of TCDD or the relative contribution of toxic impacts varies among these compounds.