陕北农村地区居民土源性线虫感染调查分析

目的 了解陕北农村居民土源性线虫感染现状、土源性线虫病防治知识知晓及健康行为形成情况.方法 按照随机抽样法,选择8个村作为调查点,以调查点≥3岁的常住人口为调查对象.采用改良加藤厚涂片法检测调查对象粪便中蛔虫、钩虫、鞭虫虫卵,12周岁以下儿童以透明胶纸法检测蛲虫卵.在每个调查点随机抽取8户以上的家庭,对家庭成员进行土源性线虫病防治知识知晓情况及卫生行为调查.结果 共粪检1 352人,阳性4人,土源性线虫总感染率为0.29％;蛲虫感染检测108人,阳性11人,蛲虫感染率为10.18％;入户调查329人,土源性线虫病防治知识知晓率为38.29％,62％以上的调查者有良好卫生行为.结论 陕北农村居民土源性线虫感染率较低,但儿童蛲虫感染率较高;人群卫生行为较好,但防治知识知晓率偏低.应继续加强防治工作,促进健康教育,以有效降低该病的危害.     

2015年云南省人体土源性线虫感染调查

目的　了解云南省人体土源性线虫病流行现状,为制定全省土源性线虫病防治对策提供科学依据。方法　2015年,采用分层整群随机抽样方法抽取云南省10个县（市）共20个调查点。以各调查点1岁及以上本地常住人口为调查对象,收集调查对象粪便,采用改良加藤厚涂片法检查土源性线虫虫卵并计数,并用试管滤纸培养法鉴别钩虫虫种,3~6岁儿童同时采用透明胶纸肛拭法检查蛲虫卵。结果　共粪检5 067人,检出土源性线虫感染950人,总感染率为18.75%,其中蛔虫、鞭虫、钩虫感染率分别为7.52%、8.47%、9.02%。3 ~ 6岁儿童同时采用透明胶纸肛拭法检查446人,检出蛲虫感染5人。对160例钩虫感染者采用试管滤纸培养法进行钩虫虫种鉴别,其中美洲钩虫感染139人、十二指肠钩虫感染16人、混合感染5人,分别占86.88%（139/160）、10.00%（16/160）和3.12%（5/160）。蛔虫、鞭虫和钩虫轻度感染者分别占67.98%（259/381）、88.58%（380/429）和94.53%（432/457）。调查的4个生态区中,以藏东⁃川西生态区人体土源性线虫感染率最高（31.79%）;10个调查县（市）中,以贡山独龙族怒族自治县人体土源性线虫感染率最高（50.13%）,宁蒗彝族自治县最低（0.40%）;高、中和低3类经济水平地区人体土源性线虫感染率分别为5.67%（43/759）、26.67%（610/2 287）和14.70%（297/2 021）;不同生态区、调查县和经济水平地区人体土源性线虫感染率差异均有统计学意义（χ2 = 342.20、814.60、201.34,P < 0.05）。男性土源性线虫感染率为18.21%（441/2 422）,女性为19.24%（509/2 645）,差异无统计学意义（χ2 = 0.89,P > 0.05）;各年龄组均有感染者,以1 ~ 9岁年龄组土源性线虫感染率最高（25.88%）;不同民族感染者中,以独龙族居民土源性线虫感染率最高（82.09%）;不同职业居民中,以学龄前儿童土源性线虫感染率最高（25.06%）;不同文化程度居民中,以文盲人群土源性线虫感染率最高（24.80%）;不同年龄组、民族、职业和文化程度人群土源性线虫感染率差异均有统计学意义（χ2 = 46.50、1 016.96、36.33、52.43,P 均 < 0.05）。结论　云南省人体土源性线虫感染率仍处于较高水平,应继续加强对低龄儿童、文化程度较低人群、农民、老人和少数民族居民等重点人群防治工作。     

2011—2013年广西农田土壤砷调查

目的了解广西农田土壤砷的污染状况。方法于2011—2013年对广西29个县(区)共580个村农田土壤中的砷含量进行检测和评价。结果共采集农田土壤样品1 740件,62.07%的土壤砷含量低于自然背景值;土壤坤含量范围为0.54~1 212 mg/kg,平均值为19.67 mg/kg,中位数为11.7 mg/kg,众数为10.6 mg/kg,砷的点位超标率为18.62%,最高超标39.4倍。土壤砷重度污染占0.63%,中度污染占1.90%,轻度污染占4.08%,轻微污染占12.01%。结论广西农田土壤砷含量的超标应引起关注。     

Breeding ecology of visceral leishmaniasis vector sandfly in Bihar state of India

Soil samples weighing 255.3 kg, collected from 50 villages of 5 visceral leishmaniasis (VL) endemic districts of Bihar state were examined for sandfly breeding, using the soil incubation method. Breeding of sandflies was detected in 46% of the villages and 7.3% of the soil samples examined. Intra-domestic soil was found to be infested with 2 species of sandflies, Phlebotomus argentipes Annandale and Brunetti and Phlebotomus papatasi (Scopoli). In comparison with human houses, P. argentipes was found to show greater propensity to breed in cattle sheds; breeding prevalences in villages and soil samples, for the species, were significantly higher in cattle sheds than in human houses. The preference for breeding sites by the sandflies appeared to be associated with the pH of the soil. P. argentipes thus preferred to breed in the alkaline soil of cattle shed, and P. papatasi in the soil with neutral pH, of human houses. The emergence of adult P. argentipes from soil samples was mainly observed from April to October.     

山西省饮水型慢性砷中毒病区环境介质中砷暴露水平调查

目的 调查山西省饮水型慢性砷中毒病区环境介质水、土壤以及自产粮食、蔬菜中的砷含量,了解该病区外环境中砷暴露水平,为病区地方性砷中毒的防治提供科学依据.方法 在山西省山阴县饮水型慢性砷中毒病区,按照《地方性砷中毒诊断标准》(WS/T 211-2001)选择126个家庭共309人作为调查对象,入户采集饮用水、土壤、当地自产粮食(小米、黍子)和蔬菜(马铃薯).水砷和粮食砷采用电感耦合等离子体质谱联用仪(ICP-MS)检测,土壤和蔬菜通过原子荧光分光光度计(AFS)定量检测砷含量.按饮水含砷量分为5组(≤10,＞ 10～50,＞50 ～ 100,＞100～200,＞200 μg/L),以≤10 μg/L组作为参考值,分析水砷暴露与皮肤病变的关系.结果 在抽取的126份饮用水样品中,水砷范围为4.04～720.00 μg/L,中位数为87.75 μg/L,超标率为63.49％(80/126);粮食砷浓度范围为0.16～4.58 mg/kg,中位数为0.66 mg/kg,超标率为98.73％(78/79);土壤和蔬菜中砷含量范围分别为5.34～13.74 mg/kg和0～ 0.30 mg/kg.用标准参考人估算通过饮水、粮食、蔬菜每天摄入的无机砷量,并与世界卫生组织(WHO)规定无机砷最大日允许摄入量(MTDI)比较,粮食中总砷含量为0.17 mg/kg时无机砷的摄入量相当于水砷浓度为10μg/L时无机砷的摄入量.同时,分析水砷暴露与皮肤病变关联强度,组间比值比(OR)分别为3.219、9.001、56.127、97.734,呈递增趋势,地方性砷中毒皮肤病变发病危险性逐渐增加,进一步对水砷暴露水平与皮肤病变严重程度进行Spearman等级相关检验,r=0.501 (P＜0.05),水砷暴露与砷中毒的皮肤病变存在关联性且水砷暴露水平越高,皮肤病变程度越严重.结论 山西省山阴县饮水型慢性砷中毒病区饮用水、自产粮食砷含量偏高,而土壤和蔬菜砷含量不高.饮用高砷井水是导致慢性砷中毒的主要危险因素,通过饮食摄入的砷也不容忽视.     

2006-2010年岷县土源性线虫病监测点流行趋势分析

目的 通过对甘肃省岷县国家级土源性线虫病监测点人群土源性线虫感染率和土壤蛔虫卵检出率的连续监测,观察其流行趋势,为制定防治策略提供依据.方法 2006-2010年期间,每年在岷县监测点整户调查1000人,改良加藤厚涂片法检测蛔虫、鞭虫虫卵,分析感染率;饱和硝酸钠漂浮法检测土壤蛔虫卵;对调查的10户土壤样品蛔虫卵计数与家庭成员蛔虫卵感染度做相关性分析.结果5年期间人群土源性线虫感染率由20.31％下降到11.08％,下降44.26％;0 ～ 15岁组为高发病人群;土源性线虫感染率最高的分别是散居儿童,其次是幼托儿童和学生;证实调查户土壤蛔虫卵计数与蛔虫感染度呈正相关,单侧t检验有统计学意义(t =4.40,P＜0.10).结论 2006-2010年岷县监测点土源性线虫感染率有明显下降,但仍在当地人群保持低发病率的流行状态.     

Microbial competition, lack in macronutrients, and acidity as main obstacles to the transfer of basidiomycetous ground fungi into (organically or heavy-metal contaminated) soils

Non-symbiotic soil microorganisms which have been expensively engineered or selected to support plant nutrition, control root diseases, degrade xenobiotic hydrocarbons, and repress or stimulate heavy metal uptake of plants fail to survive in target soils. This prompted studies into the role of chemistry and microbial pre-colonization of 23 top soils in long-term growth of basidiomycetes. Fungi are seen as auxiliary agents in soil remediation. Untreated soils (1.5 L) were colonized by lignocellulose preferring ground fungi such as Agaricus aestivalis, A. bisporus, A. campestris, A. edulis, A. macrocarpus, A. porphyrizon, Agrocybe dura, A. praecox, Clitocybe sp., Coprinus comatus, Lepista nuda, L. sordida, Macrolepiota excoriata, M. procera, Stropharia coronilla, and S. rugoso-annulata. Spawn mycelia of fairy-ring-type fungi such as Agaricus arvensis, A. fissuratus, A. langei, A. lanipes, A. pilatianus, Lyophyllum sp., and Marasmius oreades died back in contact with non-sterile soils. Fungal growth correlated positively with the soils' Ct Ca K Mg content and negatively with microbial CO2 evolution. Pasteurization and autoclaving increased mycelial growth and life span in soils pH 6.6-8.2. Growth of pH-sensitive but not of pH-tolerant fungi was inhibited on the Ca-deficient soils pH 4-4.4 (-5.6) and was not improved by autoclaving. The pretended fungistasis of acid soils to pH-sensitive fungi was controlled by N P K mineral (pH not altering) or organic (pH increasing) fertilizing as well as by neutralization with NaOH or CaCO3. Although microbial competition was mortal to 33% of the fungal mycelia inserted into natural unplanted soils, further seriously antifungal effects beyond those pretended by low pH conditions and shortage in mineral macronutrients were not identified.     

Screening of dioxin-like compounds by complementary evaluation strategy utilising ELISA,micro-EROD,and HRGC-HRMS in soil and sediments from Montevideo,Uruguay

Polychlorinated dibenzo-p-dioxins (PCDD) and dibenzofurans (PCDF) are persistent, toxic, and bioaccumulate in the environment. Due to their high analytical costs, these compounds are hardly regulated and mostly not monitored in the Third World. To overcome this, bioassays have been proposed as low-cost alternative methods. Two of the most established bioanalytical tools, the dioxin antibody-based enzyme-linked immunosorbent assay ELISA and the micro-EROD bioassay are evaluated and compared to high resolution gas chromatography and high resolution mass spectrometry (HRGC/HRMS) analytical methodology. The methods were tested using thirteen soils and sediment samples selected from diverse sites in Montevideo, Uruguay. The WHO₂₀₀₅ total toxic equivalent (WHO₂₀₀₅-TEQ) of soils ranged from 2.4 to 2212 (ng WHO₂₀₀₅-TEQ/kg dry sample) and from 0.14 to 9.4 (ng WHO₂₀₀₅-TEQ/kg dry sample) in sediments. This study shows significant contamination related to dioxin-like compounds, particularly in sites where uncontrolled burnings were carried out. ELISA and micro-EROD bioassay correlated well with HRGC/HRMS, R Spearman 0.773 and 0.913, respectively and were highly correlated to each other, R Spearman 0.879. Preliminary threshold values of bioassay toxic equivalents of 330 (ng/kg dry sample) for the micro-EROD bioassay and 220 (ng/kg dry sample) for ELISA are proposed.