淮河下游典型农村饮用水中苯并[a]芘含量与人群健康的关系

为了解淮安市淮河两岸农村居民饮用水中ρ〔B[a]P〕(苯并[a]芘浓度)与人群肿瘤发病死亡关系,选择淮安市沿淮河分布的盱眙、金湖、楚州三县(区)14个乡镇28个村,分别在丰、枯水期采集沟塘水、浅层井水、深层井水水样并测定ρ〔B[a]P〕,分析其与当地人群肿瘤发病死亡的关系. 结果表明:在159份水样中,有89.94%的水样检测到B[a]P,ρ〔B[a]P〕平均值为9.77 ng/L(95%CI,7.01～12.54 ng/L),水样超标率为25.78%. 丰水期不同水源超标率有统计学差异(χ2=10.15,P<0.01),其中沟塘水的ρ〔B[a]P〕最高. 虽然三县(区)肿瘤发病、死亡率及各区水样中的ρ〔B[a]P〕平均值有统计学差异,但不论是丰、枯水期,沟塘水、浅层井水和深层井水中的ρ〔B[a]P〕与人群肿瘤发病、死亡率之间却均未在统计学上有相关性. 淮安市淮河流域农村居民饮用水中ρ〔B[a]P〕有一定超标,但尚未证实其与当地肿瘤高发有相关性.      

Impact of chlorpyrifos on cerebrum and cerebellum maturity in suckling rats

The purpose of our study is to assess the effect of chlorpyrifos (CPF) on rat cerebral and cerebellar maturity during the suckling period. Female Wistar rats were given 0.2?g?L^?1 of CPF in drinking water, equivalent to 40?mg?kg^?1 of body weight?day^?1, from day zero until day ten after delivery. In treated pups, plasma butyrylcholinesterase (BuChE) activity was inhibited by 70%. Cerebrum and cerebellum acetyl-cholinesterase (AchE) activities were reduced by 71 and 75%, respectively. The results suggest that CPF was distributed in pup tissues through the milk of lactating mothers, resulting in inhibition of AchE activities. At age 10 days, the CPF-treated pups showed a 28% decrease in body weight, a 23 and 41% decrease in plasma free T₃ and T₄ levels and reduction in cerebral and cerebellar protein content by 36 and 38%, respectively. Consistent histological changes were found in the cerebellum of CPF treated pups, with the external granular layer being markedly developed, the Purkinje cell bodies being poorly differentiated and abnormally distributed into the internal granular layer.     

In vitro evaluation of human liver cancer cells and the potential cytotoxicity of Tecoma stans (Bignoniaceae) and Brickellia cavanillesi (Asteraceae) both single and in combination

Medicinal herbs are steadily increasing in complementary use for chronic and alterative therapies. The health risks associated with herbal supplements have therefore been identified as a top research priority. Tecoma stans (Tronadora), a Bignoniaceae plant, is a herbal drug traditionally consumed as tea in South America for the control of diabetes. It contains the alkaloids of tecomine and tecostanine which were shown as functional compounds responsible for hypoglycemic activity. However, the side effects of aqueous extracts of this herbal tea have not been reported. In this study, studies sought to evaluate the cytotoxicity of water extracts from T. stans in human hepatoblastoma (HepG2). Toxic effects of T. stans were concentration- and time-dependent in the presence and absence of fetal bovine serum (FBS). Cells were incubated for up to 72-h with varying concentrations of herbal extracts (60–100%), cytotoxicity was determined spectrophotometrically by MTT and reported in terms of % cell viability. For IC₅₀ assay (24 h exposure), cytotoxicity was found at concentration of 60–100%. Evaluation of the effects of T. stans and Brickellia cavanillesi (Asteraceae) in combination revealed that extracts of both herbal extracts' nontoxic levels of T. stans significantly reduced cell viability in a time-dependent manner. Further studies are needed regarding the identification, toxicity, and molecular mechanism of action of active compounds, as well as their cytotoxicity to other cell lines following exposure to both single and combined herbal extracts of these plants with anti-diabetic properties.     

Industries and lung cancer: A population-based case-control study in British Columbia

An investigation was conducted to identify high-risk industries for histological subtypes of lung cancer based on a large population-based case-control study in British Columbia, Canada. Occupational histories and information on smoking and relevant covariates were collected from 14,755 male incident cancer cases. Industrial risk factors for 2998 lung cancer cases, including histological subtypes were assessed by logistic regression using other cancer cases, excluding smoking-related cancers, as controls. An excess risk of lung cancer was found among workers in mining, metal manufacturing, and electric power systems for all histological-subtypes, and construction, water transport, health services for specific histological subtypes. Industrial associations that are unique to histological subtypes of lung cancer were identified. Future research needs to focus on confirming these histological associations, and identifying the risk from key exposures found within these industries (e.g. medical radiation, electromagnetic fields, and cooking fumes).     

Effects of Nonylphenol on immune function of female Sprague-Dawley rats

Nonylphenol (NP) is the final biodegradation product of nonylphenol polyethoxylates, which are widely used as surfactants in domestic and industrial products. NP was reported to exert estrogenic actions and shown to potentially adversely affect reproductive functions. However, NP influence on immune system function remains unclear. To address this issue, the effects of NP on spleen and thymus were examined in this study. Female Sprague-Dawley rats were treated with NP orally at doses of 0, 20, 80, or 200 mg/kg respectively. Data showed that NP increased the levels of natural killer (NK) cells and natural killer T (NKT) cells in peripheral blood and decreased the levels of interleukin-4 (IL-4) and interferon gamma (IFN-γ) in serum. These findings suggest that exposure to NP by oral route may induce adverse effects on the spleen and thymus and affect the immune function of female rats.     

In vitro anti-inflammatory and free radical scavenging properties of Oldenlandia auricularia

Abstract

The in vitro anti-inflammatory and antioxidant properties of extract of Oldenlandia auricularia with 70% aqueous alcohol have been evaluated. The inhibition of nuclear translocation of nuclear factor kappa-light-chain-enhancer of activated B cells in lipopolysaccharide stimulated murine macrophage cells was evaluated. Messenger ribonucleic acid levels of tumor necrosis factor-α and cyclooxygenase-2 were analysed by quantitative real time polymerase chain reaction. O. auricularia (100?mg/L) showed better anti-inflammatory and antioxidant activities when compared to its lower doses, whereas the standard drugs curcumin and diclofenac sodium showed significant anti-inflammatory and antioxidant potential. Treatment at this concentration inhibited the signalling pathway of nuclear factor kappa-light-chain-enhancer of activated B cells and messenger ribonucleic acid expression of tumor necrosis factor- α, and cyclooxygenase-2. Liquid chromatography/quadrupole time-of-flight mass spectrometry revealed the presence of previously reported compounds auricularine, ursolic acid and β-sitosterol. The observed anti-inflammatory property of O. auricularia could be due to the inhibition of nuclear factor kappa-light-chain-enhancer of activated B cells p65 sub unit nuclear translocation and inhibition of its signalling pathway.     

Cadmium and chromium in human lung tissue in relation to smoking and lung cancer

The pulmonary Cd and Cr content was determined from 53 lung cancer patients operated for cancer and from 39 patients who died of non‐malignant diseases. The results were correlated with smoking habits, pulmonary emphysema and occupational history. Both the pulmonary Cd and Cr increased with the amount of smoking. In ex‐smokers the Cr content in lung tissue did not diminish with the time since stopping smoking, but the Cd did follow the half‐life of about 9 years. The pulmonary Cd, compared with smoking habits, behaved similarly in both the lung cancer and control patients, whereas Cr in the lung cancer patients could not be explained solely by smoking, but some of the cancer patients may have been occupationally exposed to Cr. Speciation was not studied.     

Enzymatic and cellular level effects of nickel∗

The effects of Ni on hepatic enzymes of tilapia, viz. acid‐ and alkaline phosphatases, catalase and glucose‐6‐phosphatase, both under in vivo and in vitro conditions reflected the following tendencies. In vivo conditions indicated maximal increase in activity for acid phosphatase at 3.00 ppm, equivalent to 28.5%, followed by a slight decrease and increase thereafter. As for alkaline phosphatase, gradual increase in activity was observed with maximal activity at 9 ppm of Ni, equivalent to 16.8%. Catalase demonstrated similar tendencies with maximal activity at 9.0 ppm, equivalent to 101.2%. In the case of glucose‐6‐phosphatase, the tendency was the reverse with maximal inhibition at 9.00 ppm, i.e. 41.9%. In contrast to in vivo conditions, in vitro systems indicated that all investigated enzymes were inhibited in the region of 4–10% except for catalase which demonstrated a slight increase by 5–6% in activity between concentrations of 10–15 ppm of Ni but thereafter continuous inhibitory effects prevailed.

At cellular level, exposure of tilapia to a lethal dose of 9 ppm of Ni indicated not much of an adverse effect except for a slight depletion in fat and glycogen content. In the case of mitochondria, they were normal and a few large secondary lysosomes were observed. In relation to the cell membrane no dramatic change was detected.     

Metal Interactions in carcinogenesis†

Mixed exposures to a number of metallic compounds may give rise to a carcinogenic response in humans.

An interaction between occupational exposure to arsenic and cigarette smoking has been documented epidemiologically. A multiplicative effect was indicated concerning the occurrence of lung cancer when both of the exposures were present. Several experimental studies have been reported in the literature concerning interactions between benzo(a)pyrene and Fe₂O₃ as well as some other metallic compounds like Ni₃S₂, PbO, MgO and TiO₂ in relation to respiratory carcinogenicity. There is also limited evidence of a positive interaction between arsenic trioxide and benzo(a)pyrene. Particles containing V and Ni were obtained from the flue gases of power plants burning heavy fuel oil. Such particles were not carcinogenic themselves but enhanced the carcinogenicity of benzo(a)pyrene even more efficiently than Fe₂O₃.

Increased dietary selenium intakes can decrease the carcinogenicity of several organic carcinogens in animals and dietary zinc can effectuate both enhancement and inhibition of carcinogenicity depending on dietary concentration.