Synthesis and biological activity of novel N-cycloalkyl-(cycloalkylaryl)-2-[(3-R-2-oxo-2H-[1,2,4]triazino[2,3-c]quinazoline-6-yl)thio]acetamides

In this paper the novel N-cycloalkyl-(cycloalkylaryl)-2-[(3-R-2-oxo-2H-[1,2,4]triazino[2,3-c]quinazoline-6-yl)thio]acetamides synthesis by aminolysis of activated by thionyl chloride or carbonyldiimidazole [(3-R-2-oxo-2H-[1,2,4]triazino[2,3-c]quinazolin-6-yl)-thio]acetic acids and alkylation of the 3-R-6-thio-6,7-dihydro-2H-[1,2,4]triazino[2,3-c]quinazoline-2-ones potassium salts with N-cycloalkyl-(cycloalkylaryl)-2-chloroacetamides are proposed. The structures of compounds are determined by ¹H, ¹³C NMR, LC-MS and EI-MS analysis. The in vitro anticancer, antibacterial activity and Photobacterium leiognathi Sh1 bioluminescence inhibition of synthesized compounds were revealed. SAR results were discussed. Compound 4.10 was found to be the most anticancer active one, selectively influenced on the non-small cell lung and CNS cancer cell lines, especially on the HOP-92 (log GI₅₀ = −6.01) and U251 (log GI₅₀ = −6.00).     

Reproductive Potential: Its Influence on the Susceptibility of a Species to Pesticides

Acute lethal concentration estimates (72-hr LC₅₀) and population growth rates (7-day instantaneous rate of increase) of two mite species, an herbivore, the two-spotted spider miteTetranychus urticaeKoch, and the generalist predator miteIphiseius degeneransBerlese, were developed after exposure to two pesticides, dicofol and Neemix. For each pesticide, LC₅₀estimates for both species were similar, yet the two species exhibited completely different susceptibility when population growth rate was the endpoint evaluated;I. degeneranswas much more susceptible thanT. urticaeto either pesticide. For example, populations ofI. degeneransbecame extinct after exposure to 250-ppm azadirachtin, the active ingredient in Neemix, whileT. urticaepopulations became extinct after exposure to 1000 ppm. A similar relationship was found for dicofol. The no observable effect concentration (NOEC) for population growth rates after Neemix exposure was 4 ppm forI. degeneransand 125 ppm forT. urticae.These NOEC values were equivalent to the acute LC₂for the immature stage ofI. degeneransand the acute LC₆₅for the immature stage ofT. urticae.Consequently, populations ofT. urticaewere able to compensate for high losses of individuals whileI. degeneranspopulations could not compensate for losses. An analysis of reproduction data indicated that unexposedT. urticaeproduced four to five times more offspring thanI. degenerans.This in itself was important because it indicated thatI. degeneranswas intrinsically more susceptible thanT. urticaebecause similar effects on reproduction would be more devastating to the species with a lower reproductive rate. Results indicate that a species' reproductive potential can greatly influence its susceptibility to toxicants.     

Environmental monitoring of occupational exposure to <Emphasis Type="Italic">N</Emphasis>,<Emphasis Type="Italic">N</Emphasis>-dimethylformamide: comparison between active and diffusive sampling

Objectives The objective of this study is to optimize the evaluation of the exposure to N,N-dimethylformamide (DMF) in synthetic leather factories by diffusive samplers. The DMF exposure was monitored in synthetic leather factories by two sampler types: active and diffusive. Methods Air measurements were carried out using two different personal air samplers, a diffusive and an active one. The diffusive sampling method, TK200 with charcoal filters, was examined in comparison with pumping through NIOSH silica gel tubes workplace air as with the currently available “gold standard”. The evaluation was carried out, in two different years but in the same season, for all the duration of the shift, i.e. 8 h on workers employed in five different factories in the district of Florence and Prato (Italy). Results The statistical and graphical analysis of data show a good correlation between active and passive samplers (r = 0.96, P < 0.001, n = 91), a good linear regression (DMF_diffusive = 0.95 DMF_active + 0.15, R ² = 0.92), a not statistically significant difference between data (tested by paired t test and non-parametric Wilcoxon test). Moreover, all these results are confirmed for data lower and higher than TLV-TWA, in particular we found a significant Pearson correlation (r = 0.92, P < 0.001, n = 83; r = 0.92, P < 0.05, n = 8, respectively) and a significant linear regression (DMF_diffusive = 0.88 DMF_active + 0.73, R ² = 0.86; DMF_diffusive = 0.90 DMF_active + 3.76, R ² = 0.85). Besides, the analysis of graphical representations confirmed the previous evidences. Finally, we can not find a significant difference between different types of job. Conclusions Due to the good agreement between the two groups of data, the TK200 samplers can be considered as a simpler approach than the pump for screening worker exposures to DMF.     

A New Developmental Toxicity Test for Pelagic Fish Using Anchoveta (<Emphasis Type="Italic">Engraulis ringens</Emphasis> J.)

A series of six 96-h static bioassays were performed to validate the use of anchoveta (Engraulis ringens) embryos as test organisms for ecotoxicological studies. The standardization protocol utilized potassium dichromate (K₂Cr₂O₇) as a reference toxicant and egg mortality as the endpoint. The results indicated that the mean sensitivity of anchoveta embryos to potassium dichromate was 156.1 mg L⁻¹ (range: 131–185 mg L⁻¹). The statistical data analysis showed high homogeneity in LC50 values among bioassays (variation coefficient = 11.02%). These results demonstrated that the protocol and handling procedures implemented for the anchoveta embryo bioassays comply with international standards for intra-laboratory precision. After secondary treatment, an effluent from a modern Kraft pulp mill was tested for E. ringens embryo toxicity, finding no significant differences from the controls.     

Relationships Between Leaching of Methylmercury from the Soil and the Basic Characteristics of Alkali Soil Polluted by Mercury in Guizhou China

To determine the relationship between soluble methylmercury and soil characteristics which was contaminated by mercury, several experiments were conducted. As a result, a good correlation was founding between the leached methylmercury level from soil and the EC (electronic conductivity) level of soil. Moreover, to grasp the relationship between soluble methylmercury and soluble anions from soil, several anions (Cl⁻, NO³⁻, SO₄ ²⁻) were measured using the ion chromatography method. Although the correlation coefficient was small (r = 0.40), only a correlation between the level of SO₄ ²⁻ and leached methylmercury was recognized.     

Removal of Methyl Parathion in Water,by <Emphasis Type="Italic">Dugesia dorotocephala</Emphasis>

The aim of this study was to determine the efficiency of Dugesia dorotocephala on Methyl parathion removal. An initial concentration of 1.25 μg mL⁻¹ of MeP was used to evaluate the removal capacity of planarian. A first-order removal kinetics was obtained with a disappearance rate constant (k _r) of 0.49 days⁻¹ and 69% efficiency on contaminant removal. This is significantly different (p < 0.5) from the degradation occurring in control systems, leading us to conclude that D. dorotocephala effectively removes MeP from contaminated water.     

Docking-based 3D-QSAR study of HIV-1 integrase inhibitors

In this study, 3-aroyl-1,1-dioxo-1,4,2-benzodithiazine and 4-chloro-N-(4-oxopyrimidin-2-yl)-2-mercaptobenzenesulfonamide derivatives (HIV-1 integrase inhibitors) were used for CoMFA and CoMSIA to determine the substructures required for the activity of these molecules. To explore the binding mode of inhibitors, docking studies were done and docked conformation of highly active molecule was used as template for alignment. The best CoMFA model yielded the cross validation r²_cv = 0.728, non-cross validation r²_ncv = 0.934 and predictive r²_pred = 0.708. The best CoMSIA model yielded a cross validation r²_cv = 0.794, non-cross validation r²_ncv = 0.928 and predictive r²_pred = 0.59. It was found that steric (CoMFA) and hydrophobic fields (CoMSIA) have large contribution towards the inhibitory activity than the other fields. Docking and 3D-QSAR studies have provided clues to a better understanding of interaction between the inhibitors and HIV-1 integrase.     

α-Tocopherol, fatty acids and their correlations in Bulgarian foodstuffs

HPLC and GC methods were used for the analysis of 33 foodstuffs divided into 7 groups: cereals, oils and fats, milk and dairy products, meat, eggs and poultry, fish and nuts. The richest sources of α-tocopherol (α-T), seed oils, show considerable variations of α-T (11.0 mg% soybean oil–44.88 mg% sunflower seed oil), as does the content of PUFA (12.72 g% olive oil–66.87 g% sunflower seed oil) with approximately the same content of total lipids (TL) (99.79–99.89 g%). A correlation was established between α-T and total lipids r=0.61 (T=4.28, P>99%). An even higher correlation was found between α-T and polyunsaturated fatty acids r=0.80 (T=7.42, P>99%). Regarding the essential n-6 and n-3 fatty acids α-T was established to correlate only with n-6 fatty acids r=0.82 (T=7.50, P>99%).     

Evaluation of urinary biomarkers of exposure to benzene: correlation with blood benzene and influence of confounding factors

Purpose   trans,trans-Muconic acid (t,t-MA) is generally considered as a useful biomarker of exposure to benzene. However, because of its lack of specificity, concerns about its value at low level of exposure have recently been raised. The aim of this study was (a) to compare t,t-MA, S-phenylmercapturic acid (SPMA) and benzene (B-U) as urinary biomarkers of exposure to low levels of benzene in petrochemical workers and, (b) to evaluate the influence of sorbic acid (SA) and genetic polymorphisms of biotransformation enzymes on the excretion of these biomarkers. Method  A total of 110 workers (including 24 smokers; 2–10 cigarettes/day) accepted to take part in the study. To assess external exposure to benzene, air samples were collected during the whole working period by a passive sampling device attached close to the breathing zone of 98 workers. Benzene was measured in blood (B-B) samples taken at the end of the shift, and was considered as the reference marker of internal dose. Urine was collected at the end of the shift for the determination of B-U, SPMA, t,t-MA, SA and creatinine (cr). B-U and B-B were determined by head-space/GC–MS, SPMA and SA by LC-MS, t,t-MA by HPLC-UV. Results  Most (89%) personal measurements of airborne benzene were below the limit of detection (0.1 ppm); B-B ranged from <0.10 to 13.58 μg/l (median 0.405 μg/l). The median (range) concentrations of the urinary biomarkers were as follows: B-U 0.27 μg/l (<0.10–5.35), t,t-MA 0.060 mg/l (<0.02–0.92), SPMA 1.40 μg/l (0.20–14.70). Urinary SA concentrations ranged between <3 and 2,211 μg/l (median 28.00). Benzene concentration in blood and in urine as well as SPMA, but not t,t-MA, were significantly higher in smokers than in non-smokers. The best correlation between B-B and urinary biomarkers of exposure were obtained with benzene in urine (μg/l r = 0.514, P < 0.001; μg/g cr r = 0.478, P < 0.001) and SPMA (μg/l r = 0.495, P < 0.001; μg/g cr r = 0.426, P < 0.001) followed by t,t-MA (mg/l r = 0.363, P < 0.001; mg/g cr r = 0.300, P = 0.002). SA and t,t-MA were highly correlated (r = 0.618, P < 0.001; corrected for cr r = 0.637). Multiple linear regression showed that the variation of t,t-MA was mostly explained by SA concentration in urine (30% of the explained variance) and by B-B (12%). Variations of SPMA and B-U were explained for 18 and 29%, respectively, by B-B. About 30% of the variance of B-U and SPMA were explained by B-B and smoking status. Genetic polymorphisms for biotransformation enzymes (CYP2E1, EPHX1, GSTM1, GSTT1, GSTP1) did not significantly influence the urinary concentration of any of the three urinary biomarkers at this low level of exposure. Conclusion  At low levels of benzene exposure (<0.1 ppm), (1) t,t-MA is definitely not a reliable biomarker of benzene exposure because of the clear influence of SA originating from food, (2) SPMA and B-U reflect the internal dose with almost similar accuracies, (3) genetically based inter-individual variability in urinary excretion of biomarkers seems negligible. It remains to assess which biomarker is the best predictor of health effects.     

A study on prevalence of multi-drug-resistant (MDR) Salmonella in water sprinkled on fresh vegetables in Bareilly, Moradabad, and Kanpur (northern Indian cities)

Water-borne and food-borne diseases are common in summers and monsoons in India. This study between March 2004 to September 2004 on microbiological quality of water used by vegetable vendors to keep their vegetables fresh was conducted to asses the role of water as a source of Salmonella. Of the 309 samples collected from Bareilly (80 vegetable vendors, 47 ponds, five municipal water taps), Moradabad (74 vegetable vendors, three ponds, five municipal water taps) and Kanpur (84 vegetable vendors, six ponds, five municipal water taps), 82 (26.5%) and 27 (8.7%) had Escherichia coli and Salmonella enterica strains, respectively. The study revealed that sprinkling water was contaminated with 0.00–6.81 log₁₀ cfu ml⁻¹ of coliforms, 4.16 log₁₀ to 9.46 log₁₀ cfu ml⁻¹ of heterotrophic aerobic bacteria, 0.00 to 7.23 log₁₀ cfu ml⁻¹ of non-lactose fermenters, 0.00 to 5.56 log₁₀ cfu ml⁻¹ of Salmonella and 0.00 to 7.77 log₁₀ cfu ml⁻¹ of yeast and moulds. Similarly, microbial counts in pond water samples (Bareilly) were 0.00 to 6.06 log₁₀ cfu ml⁻¹ of faecal coliforms, 5.12 log₁₀ to 8.09 log₁₀ cfu ml⁻¹ of heterotrophic aerobic bacteria, 0.00 to 6.37 log₁₀ cfu ml⁻¹ of non-lactose fermenters, 0.00 to 5.73 log₁₀ cfu ml⁻¹ of Salmonella and 0.00 to 7.82 cfu log₁₀ ml⁻¹ of yeasts and moulds. Presence of Salmonella in water sample had negative correlation with number of coliforms and positive correlation with number of non-lactose fermenters, as of the 16 (6.7%) Salmonella positive samples of water from vegetable vendors, ten were negative for coliforms. Similarly, of the 11 pond-water samples positive for Salmonella, six were negative for coliforms, and negative correlation (−0.55) between coliform count and Salmonella was statistically significant (r_0.01). On the other hand, Salmonella counts could be positively correlated (r_0.01) with counts of non-lactose fermenters. Salmonella isolates from water for sprinkling on vegetables belonged to S. Anatum (1), S. Newport (1), S. Saintpaul (6), S. Virchow (4) and S. Weltevreden (4) serovars while isolates pond water samples belonged to S. Saintpaul (9) and S. Newport (2) serovars. Except two Salmonella isolates (one each of serovar S. Anatum and S. Weltevreden), all had multiple drug resistance and could be classified into 21 resistotypes. All the Salmonella isolates were sensitive to ceftriaxone and streptomycin while resistant to sulphamethizole. The study indicated that pond water (used by farmers for washing vegetables) and water used by vegetable vendors for sprinkling on vegetables might have an important role as a source of multiple-drug-resistant zoonotic Salmonella.     

不同性别人群免疫球蛋白G N-糖基化结构谱型比较

目的 对不同性别人群的免疫球蛋白G（IgG） N-糖基结构谱型进行分析比较。方法 采用整群抽样,以2012年1-6月在北京市宣武医院体检的669名居民为研究对象,留取空腹静脉血5 ml,对IgG N-糖基进行分离、纯化、标记后,采用超高压液相色谱串联质谱法对IgG N-糖基进行检测,最终得到24个色谱峰,每个峰代表不同的糖基结构。不同性别人群的糖基结构比较采用两独立样本t检验或非参数检验,P<0.05为差异有统计学意义。结果 669名参与者中男性235人（35.13%）,女性434人（64.87%）,平均年龄为（44.23±9.82）岁。女性核心岩藻糖基化水平Fⁿ（Z=-2.192,P=0.028）高于男性;女性半乳糖基化水平G0ⁿ（Z=-7.898,P<0.001）、G1ⁿ（Z=-2.343,P=0.019）低于男性,而G2ⁿ（Z=-8.414,P<0.001）水平高于男性;女性唾液酸化水平F^totalS1/F^totalS2（Z=-5.049,P<0.001）、FS1/FS2（Z=-3.336,P=0.001）高于男性。结论 IgG N-糖基结构水平可能与性别有关。     

Structure-activity relationship studies of CNS agents. Part 29. N-Methylpiperazino-substituted derivatives of quinazoline, phthalazine and quinoline as novel α1, 5-HT1A and 5-HT2A receptor ligands

New N-methylpiperazino-substituted quinazolines 8 and 9, phthalazine 13, and quinoline 19 have been synthesized. The receptor binding profiles (α₁, 5-HT_1A, 5-HT_2A) of these compounds and their analogs (7–22) have been determined. It has been demonstrated that orientation of a local dipole moment of the heteroaromatic ring system affects both the α₁ and 5-HT_2A affinity of the investigated class of ligands. Distortion of the coplanar unfused heteroaromatic ring system results in a decreased 5-HT_2A affinity. 4-(4-Methylpiperazino)-2-(2-thienyl)quinoline 18 is the most active and selective α₁ ligand (K_i = 4.9 nM) with a much lower affinity for 5-HT_1A (K_i = 3420 nM) and 5-HT_2A (K_i = 211 nM) receptors.     

Mercury and Drought Along the Lower Carson River,Nevada: I. Snowy Egret and Black-Crowned Night-Heron Annual Exposure to Mercury, 1997–2006

The dynamic nature of the annual volume of water discharged down the Carson River over a 10-year period, which included a century flood and drought, was examined in order to gain a better understanding of mercury movement, biological availability, and exposure to waterbirds nesting at Lahontan Reservoir. Total annual water discharge directly influenced total mercury (THg) in unfiltered water above the reservoir and downstream of a mining area, whereas methyl mercury (MeHg) at the same site was negatively related to annual discharge. Annual water storage at Lahontan Reservoir in the spring and early summer, as expected, was directly related to annual Carson River discharge. In contrast to the findings from above the reservoir, annual MeHg concentrations in water sampled below the reservoir were positively correlated with the total discharge and the amount of water stored in the reservoir on 1 July; that is, the reservoir is an important location for mercury methylation, which agrees with earlier findings. However, unfiltered water MeHg concentrations were about 10-fold higher above than below the reservoir, which indicated that much MeHg that entered as well as that produced in the reservoir settled out in the reservoir. Avian exposure to mercury at Lahontan Reservoir was evaluated in both eggs and blood of young snowy egrets (Egretta thula) and black-crowned night-herons (Nycticorax nycticorax). Annual MeHg concentrations in unfiltered water below the reservoir, during the time period (Julian Days 90–190) when birds were present, correlated significantly with mercury concentrations in night-heron blood (r ² = 0.461, p = 0.027), snowy egret blood (r ² = 0.474, p = 0.024), and night-heron eggs (r ² = 0.447, p = 0.029), but not snowy egret eggs. A possible reason for lack of an MeHg water correlation with snowy egret eggs is discussed and relates to potential exposure differences associated with the food habits of both species. THg concentrations in water collected below the reservoir were not related to egg or blood mercury concentrations for either species.     

Toxicity and physiological effects of neem pesticides applied to rice on the Nilaparvata lugens Stål, the brown planthopper

The effects of two different neem products (Parker Oil™ and Neema^®) on mortality, food consumption and survival of the brown planthopper, Nilaparvata lugens Stål (BPH) (Homoptera: Delphacidae) were investigated. The LC₅₀ (3.45 ml/L for nymph and 4.42 ml/L for adult in Parker Oil™ treatment; 4.18 ml/L for nymph and 5.63 ml/L for adult in Neema^® treatment) and LC₉₀ (8.72 ml/L for nymph and 11.1 ml/L for adult in Parker Oil™ treatment; 9.84 ml/L for nymph and 13.07 ml/L for adult in Neema^® treatment) were identified by probit analysis. The LC₉₀ (equal to recommended dose) was applied in the rice field. The effective concentration of both Parker Oil™ and Neema^® took more than 48 h to kill 80% of the N. lugens. Fourth instar nymph and adult female N. lugens were caged on rice plants and exposed to a series (both LC₅₀ and LC₉₀) of neem concentrations. Nymph and adult female N. lugens that were chronically exposed to neem pesticides showed immediate mortality after application in laboratory experiment. The quantity of food ingested and assimilated by N. lugens on neem-treated rice plants was significantly less than on control rice plants. The results clearly indicate the neem-based pesticide (Parker Oil™ and Neema^®), containing low lethal concentration, can be used effectively to inhibit the growth and survival of N. lugens.     

Metrics of whole-body vibration and exposure–response relationship for low back pain in professional drivers: a prospective cohort study

Objectives  The objective of this study was to investigate the relation between alternative measures of exposure to whole-body vibration (WBV) and low back pain (LBP) in professional drivers. Methods  The incidence of 12-month LBP, high pain intensity (numerical rating scale score > 5), and disability in the lower back (Roland and Morris disability scale score ≥ 12) was investigated in a cohort of 537 drivers over a 2-year follow-up period. LBP outcomes, individual characteristics, and work-related risk factors were investigated by direct interview using a structured questionnaire. Daily vibration exposure was expressed in terms of either equivalent acceleration over an 8-h reference period [A(8), root-mean-square (r.m.s.) method] or vibration dose value [VDV, root-mean-quad (r.m.q.) method]. From the vibration magnitudes measured on vehicles and total exposure duration, seven alternative measures of cumulative vibration exposure were calculated for each driver, using expressions of the form Σa _i ^m t _i , where a _i is the frequency-weighted r.m.s. or r.m.q. acceleration magnitude on vehicle i (a _ws or a _wq, respectively), t _i is the lifetime exposure duration for vehicle i, and m = 0, 1, 2, or 4. Results  In the drivers’ cohort, the cumulative incidence of LBP outcomes were 36.3% for 12-month LBP, 24.6% for high pain intensity, and 19.2% for disability in the lower back. A transition model, which takes into account the temporal sequence of cause and effect and captures the longitudinal part of the relationship, showed that VDV performed better than A(8) for the prediction of LBP outcomes. After adjusting for potential confounders, test for trends suggested an increased risk for developing high pain intensity and disability over time (and, to a lesser extent, 12-month LBP) with the increases of cumulative vibration doses computed from lifetime exposure duration and r.m.q. vibration magnitude (i.e. ∑[a _wqi ^m t _i ]). Measures of exposure duration, either daily or lifetime, also provided good indications of risk for LBP outcomes over time. Physical work load, but not psychosocial environment, was significantly associated with the occurrence of LBP outcomes over time. Conclusions  Measures of vibration exposure derived from exposure duration (daily or lifetime) and r.m.q. acceleration magnitude (VDV, ∑[a _wqi ^m t _i ]) were better predictors of LBP outcomes over time than measures of vibration exposure including r.m.s. acceleration (A(8), ∑[a _wsi ^m t _i ]). Patterns of exposure–response relationship were more evident for the outcomes high pain intensity or disability in the lower back than for the binary response 12-month LBP.     

Increase of Intracellular free [CA2+] in Single Human Motile Spermatozoa Treated with Human Follicular Fluid

The intracellular free [Ca²⁺] concentration ([Ca²⁺]_i) in individual human sperm was measured using a fluorescent Ca²⁺ indicator. In 18 of 23 motile sperm (78.3%), [Ca²⁺]_i increased significantly and promptly after addition of 20% human follicular fluid (hFF), but in the others it did not increase. The mean resting [Ca²⁺]_i level of sperm in which [Ca²⁺]_i increased after addition of 20% hFF (the influx group) was significantly lower than those in which it did not increase (112.8 ± 40.1 nM vs. 156.9 ± 13.5 nM,p <. 05). After addition of 20% hFF, the mean [Ca²⁺]_i in the influx group reached a peak value of 210.7± 24.7 nM within 30 s and then decreased slowly; the mean [Ca²⁺]_i values 1, 5, 10, and 15 min after addition of 20% hFF were 179.3 ± 31.4, 174.3 ± 30.2, 172.5 ± 27.8, and 175.1 ± 27.2 nM, and all values were significantly higher than the resting level (p <. 01). The frequency distribution of [Ca²⁺]_i after addition of 20% hFF was shifted toward higher concentrations (p <. 01). However, the addition of 20% hFF did not increase the percentage of live acrosome reaction (before 3.8 ± 0.9% vs. after 2.9 ± 0.5%, respectively). Thus, hFF increased [Ca²⁺]_i in about 80% of the motile sperm. Relatively high [Ca²⁺]_i levels persisted for at least 10–15 min after its addition. However, hFF did not trigger a rapid response in acrosome reaction.     

Biomarkers of low-level mercury exposure through fish consumption in pregnant and lactating Slovenian women

In order to assess the mercury exposure of pregnant and lactating women in Slovenia, levels of total mercury (THg) and methylmercury (MeHg) were determined in hair, cord blood and breast milk. In addition, the frequency of fish consumption was estimated, because fish is generally the main pathway for human exposure to MeHg. Hair samples were collected from 574 women participating in this study, while cord blood and breast milk samples were collected from 446 and 284 women, respectively. As expected, the levels of THg in hair (median (Med)=297 ng/g, 10th percentile (P10)=73 ng/g, 90th percentile (P90)=781 ng/g), cord blood (Med=1.5 ng/g, P10=0.5 ng/g, P90=4.2 ng/g) and breast milk (Med=0.2 ng/g, P10=0.06 ng/g, P90=0.6 ng/g) were low, due to low consumption of fish (X=25 g/day). A significant linear correlation was found between levels of ln THg in hair and ln THg in cord blood (r=0.87, 95% confidence interval (CI): 0.84–0.89), between levels of ln THg in hair and ln MeHg in cord blood (r=0.94, 95% CI: 0.90–0.96) and between ln THg levels in cord blood and ln THg levels in breast milk (r=0.36, 95% CI: 0.25–0.47). Spearman's rank correlations between the frequency of fish consumption and THg in hair (r_s=0.35, 95% CI: 0.28–0.42), and between the frequency of fish consumption and THg in cord blood (r_s=0.43, 95% CI: 0.36–0.51) or MeHg in cord blood (r_s=0.31, 95% CI: 0.06–0.52) were weak. This could be due to the approximate information on fish consumption obtained from the questionnaires, the high variability of MeHg concentrations in fish and a relatively high proportion of inorganic mercury in the biomarkers which originates from sources other than fish. In conclusion, THg levels in cord blood, THg levels in hair and MeHg levels in cord blood are suitable biomarkers of low-level Hg exposure through fish consumption. Compared to cord blood, hair samples are easy to collect, store and analyse.     

拟康宁木霉引起血流感染1例及文献综述

目的 报告1例拟康宁木霉引起血流感染患者的诊断、治疗情况。方法 总结1例拟康宁木霉引起血流感染患者的临床诊疗过程,并检索数据库相关文献进行复习。结果 患者男性,60岁,因“间断发热伴腰膝痛半月余”入院,依据检查结果,给予头孢曲松钠、左氧氟沙星、更昔洛韦治疗无明显好转。外周血第二代测序技术(NGS)检测为拟康宁木霉,考虑木霉菌血流感染,给予伏立康唑口服后患者发作间期逐渐延长,由每2～3 d发作一次延长至每4～5 d发作一次,体温峰值有所下降,腰及膝关节疼痛程度减轻;出院后继续口服伏立康唑,随访1个月余患者逐渐退热,腰膝痛随之缓解,但出院2个月后猝死。检索外文文献报道病例38例(中国1例),中文文献报道病例2例,共计40例。文献检索统计木霉感染患者基础疾病以器官移植(12例)、血液病(9例)、腹膜透析(6例)为主,患者临床表现以肺部感染(8例)、腹膜炎(6例)、播散感染(5例)为主,地区分布以欧美国家居多(26例),亚洲5例,非洲2例,南美洲1例,地区不详6例。检出病原体以长梗木霉为主(24例)。结论 木霉是一种机会致病菌,多发生于免疫功能低下者,易误诊,建议尽早送检NGS明确病原体,以争...