发泡胶在鼻咽癌放疗中对剂量分布的影响

目的：研究在鼻咽癌放射治疗中应用发泡胶进行体位固定对剂量分布的影响。方法：随机选取11例应用头颈肩热塑膜联合发泡胶进行体位固定的鼻咽癌患者，在Pinnacle计划系统中将空白CT值设置到发泡胶的CT值以下，以确保发泡胶的CT值被计算在内，作为第一组计划（Plan_F）。同时，复制第一组计划并在定位图像上勾画出发泡胶，设置发泡胶的CT值为0，在不改变射野分布、权重及计划跳数的情况下重新计算剂量分布，作为第二组计划（Plan_N）。比较两组计划的靶区及周围正常组织的剂量分布。结果：对于靶区（GTVnx、GTVnd、GTVrpn、PGTVnx、CTV1、PTV1、CTV2、PTV2）的最小剂量Dmin，最大剂量Dmax，平均剂量Dmean去除发泡胶之后，所测 255组数据中仅有6组数据出现减小（约占2.4%），Dmin、Dmax和Dmean的变化度（%）（X±SD）依次为0.215±0.969、 0.395±0.623和 0.442±0.178，其中除了GTVrpn的Dmin（P=0.727）和Dmax（P=0.142），PGTVnx的Dmin（P=0.623），CTV1 Dmin（P=0.713），CTV2 Dmax（P=0.066），其他评估指标皆显示发泡胶使用组剂量低于去除发泡胶组（P＜0.05）；而对于周围正常组织（脑干、脊髓、左右晶体、左右视神经和腮腺）的Dmean和Dmax去除发泡胶之后，所测的154组数据中仅有14组数据出现减小（约占9.1%），Dmax和Dmean的变化度（%）（X±SD）依次为0.194±0.192 和0.129±0.128，其中除了左、右晶体的平均剂量Dmean（P值分别为0.123和0.06），其余各项指标同样显示发泡胶使用组剂量低于去除发泡胶组（P＜0.05）。结论：发泡胶的使用降低了实际治疗过程中受照部位的剂量，但发泡胶对剂量变化的影响都在目前临床可接受的范围之内。     

Exposure to ambient air pollution and the incidence of lung cancer and breast cancer in the Ontario Population Health and Environment Cohort

Lung and female breast cancers are highly prevalent worldwide. Although the association between exposure to ambient fine particulate matter (PM_2.5) and lung cancer has been recognized, there is less evidence for associations with other common air pollutants such as nitrogen dioxide (NO₂) and ozone (O₃). Even less is known about potential associations between these pollutants and breast cancer. We conducted a population-based cohort study to investigate the associations of chronic exposure to PM_2.5, NO₂, O₃ and redox-weighted average of NO₂ and O₃ (O_x) with incident lung and breast cancer, using the Ontario Population Health and Environment Cohort (ONPHEC), which includes all long-term residents aged 35–85 years who lived in Ontario, Canada, 2001–2015. Incident lung and breast cancers were ascertained using the Ontario Cancer Registry. Annual estimates of exposures were assigned to the residential postal codes of subjects for each year during follow-up. We used Cox proportional-hazards models adjusting for personal- and neighborhood-level covariates. Our cohorts for lung and breast cancer analyses included ~4.9 million individuals and ~2.5 million women, respectively. During follow-up, 100,146 incident cases of lung cancer and 91,146 incident cases of breast cancer were diagnosed. The fully adjusted analyses showed positive associations of lung cancer incidence with PM_2.5 (hazard ratio [HR] = 1.02 [95% CI: 1.01–1.05] per 5.3 μg/m³) and NO₂ (HR = 1.05 [95% CI: 1.03–1.07] per 14 ppb). No associations with lung cancer were observed for O₃ or O_x. Relationships between PM_2.5 and NO₂ with lung cancer exhibited a sublinear shape. We did not find compelling evidence linking air pollution to breast cancer.     

Fine particulate matter and incidence of metabolic syndrome in non-CVD patients: A nationwide population-based cohort study

Background

It has been reported that particulate matter (PM) is associated with cardiovascular diseases (CVD) while metabolic syndrome is also an important risk factor for CVD. However, few studies have investigated the epidemiological association between PM and metabolic syndrome.

The Relationship Between Air Pollution and Lung Cancer in Nonsmokers in Taiwan

Introduction

For never-smokers (smoked <100 lifetime cigarettes), lung cancer (LC) has emerged as an important issue. We aimed to investigate the effects of prevalence changes in tobacco smoking and particulate matter (PM) 2.5 (PM_2.5) levels on LC in Taiwan, in relation to contrasting PM_2.5 levels, between Northern Taiwan (NT) and Southern Taiwan (ST).

Effects of ambient particulate matter on vascular tissue: a review

ABSTRACT

Fine and ultra-fine particulate matter (PM) are major constituents of urban air pollution and recognized risk factors for cardiovascular diseases. This review examined the effects of PM exposure on vascular tissue. Specific mechanisms by which PM affects the vasculature include inflammation, oxidative stress, actions on vascular tone and vasomotor responses, as well as atherosclerotic plaque formation. Further, there appears to be a greater PM exposure effect on susceptible individuals with pre-existing cardiovascular conditions.     

Association between long-term exposure of ambient air pollutants and cardiometabolic diseases: A 2012 Korean Community Health Survey

Background and aim

The associations of long-term exposure to particulate matter <10 μm in size (PM₁₀), nitrogen dioxide (NO₂), carbon monoxide (CO), sulfur dioxide (SO₂), and ozone (O₃) with cardiometabolic diseases (CMD) remain uncertain in the Korean population. Therefore, we sought to examine the associations between PM₁₀, NO₂, CO, SO₂, and O₃ and CMD using data collected from the Korean Community Health Survey.

林国华针灸治疗难治性突发性耳聋经验撷要

总结林国华教授针灸治疗难治性突发性耳聋经验,并对典型医案进行介绍。林国华教授认为本病多因少阳经气厥塞所致,提倡尽早针灸干预,治病求本,谨守"少阳暴厥"之病机,谨遵"疏解少阳,通耳开窍"之法,临证必用听宫,主取少阳经穴,辅予辨经取穴,巧施发蒙针法与气流灌耳法,妙用岭南火针疗法,必要时调气调神、加取募穴,共奏通耳复聪之效。     

Niacinamide and 12‐hydroxystearic acid prevented benzo(a)pyrene and squalene peroxides induced hyperpigmentation in skin equivalent

Skin surface is constantly exposed to environmental and secreted stressors such as UV, air pollution and peroxidized sebum. The current study aims to use reconstructed human skin equivalents to demonstrate topical stressor‐induced hyperpigmentation and evaluate bioactives’ potential protective effect. Given that polycyclic aromatic hydrocarbons are representative airborne particle‐bound organic compounds with known relevance to pigmentation pathways, benzo(a)pyrene was selected as surrogate environmental toxin. On the other hand, squalene monohydroperoxides are well‐characterized sebum peroxidation product under UV and pollutant exposure, thus are used as another representative skin stressor. With 3‐day continuous exposure, 30 pmol/cm² of benzo(a)pyrene and 3.4 nmol/cm² of squalene monohydroperoxides induced significant viability loss, inflammatory response, and approximately 10 shades of pigmentation increase in pigmented living skin equivalents. At the same time, pretreatment and co‐treatment with 12‐hydroxystearic acid (12‐HSA, 20 μmol/L) or niacinamide (5 mmol/L) ameliorated such stressor‐induced consequences. Niacinamide was particularly effective against benzo(a)pyrene damage, probably as a substrate for important NAD+ dependent detoxification pathways, while 12‐HSA was potent against squalene monohydroperoxides through barrier enhancing, anti‐inflammatory, and anti‐oxidative mechanisms. In summary, topical stressor‐induced hyperpigmentation was achieved in vitro, with known bioactives showing protective benefits.