Combined promoting effects of low-Pd-containing and Cu-doped LaCoO3 perovskite supported on cordierite for the catalytic combustion of benzene

The catalytic activities for benzene oxidation and resistance to SO2 poisoning were tested for a series of Pd/La-Cu-Co-O/cordierite catalysts, which were prepared using a multiple-step impregnation method. The XRD, SEM, and IR characterization techniques were performed to investigate the relationship between the catalytic performance and its physicochemical properties. When Pd/La-Cu-Co-O/cordierite catalysts with Pd loadings of 0.06 and 0.08 % were prepared at a calcination temperature of 500 °C for 5 h, they exhibited similar catalytic activity and sulfur resistance. When the concentration of benzene was 1500 ppm and the GHSV was 20000 h(-1), the benzene conversion was above 95 % at a reaction temperature of 350 °C in SO2 existing at 100 ppm. These results were mainly attributed to the cooperation between La-Cu-Co-O perovskite and the noble metal Pd. Specifically, the addition of copper can strengthen the catalytic activity of La-Co-O/cordierite catalysts by decreasing the crystalline size of the active ingredients. A moderate Pd addition can drastically improve the sulfur resistance and further improve the catalytic activity of the La-Cu-Co-O/cordierite catalyst.

Exposure to electromagnetic fields aboard high-speed electric multiple unit trains

High-speed electric multiple unit (EMU) trains generate high-frequency electric fields, low-frequency magnetic fields, and high-frequency wideband electromagnetic emissions when running. Potential human health concerns arise because the electromagnetic disturbances are transmitted mainly into the car body from windows, and from there to passengers and train staff. The transmission amount and amplitude distribution characteristics that dominate electromagnetic field emission need to be studied, and the exposure level of electromagnetic field emission to humans should be measured. We conducted a series of tests of the on board electromagnetic field distribution on several high-speed railway lines. While results showed that exposure was within permitted levels, the possibility of long-term health effects should be investigated.

Clastogenic but Not Apoptotic Effects on Human Artery Endothelial Cells by Concentrations of Inorganic Lead Inhibiting Their Nitric Oxide Production

Human coronary artery endothelial cells (HCAEC 5156) were cultured as monolayers and exposed to concentrations of lead (as acetate, Pb) in the culture medium similar or lower than those commonly found in the blood of human beings occupationally or environmentally exposed to this element. Only at the concentration of 200 ng/mL, Pb reduced growth rate of HCAEC 5156 cells starting from the 3rd day and up to the 5th day of incubation. On the other hand, Pb (0.2, 2 and 200 ng/mL) increased concentration-dependently micronuclei formation in binucleated HCAEC5156 cells, as it was shown by the cytokinesis-blocked micronucleus assay (CBMN assay) carried out after 48 hours of exposure to the metal. However, Pb was unable, at all the above concentrations, to induce apoptosis in HCAEC 5156 cells following a 48 hour-exposure, as shown by an electrophoretic apoptotic DNA fragmentation test. Moreover, Pb (2 and 200 ng/mL) reduced significantly the concentration of nitric oxide (NO, determined analytically as L-citrulline) in both culture medium and cytosol of HCAEC 5156 cells following a 7 day-exposure to the element. Results were discussed also in relation to evidences of other studies reporting genotoxic and/or apoptotic effects of Pb on various cell types at very elevated dosages or concentrations. The observed clastogenic effects of Pb were explained through a series of mechanisms involving interactions between oxygen reactive species and NO and/or reduced NO synthesis in the endothelium, thus leading to a depressed NO bioavailability. This research first shows that Pb is provided with clastogenic but not apoptotic effects on cultured human endothelial cells. It was emphasized that such effects are induced by Pb concentrations similar to those commonly found in blood and tissues of laboratory animals showing Pb induced cardiovascular and/or neuropsychological alterations.

Subclinical Neurophysiological Effects of Manganese in Welding Workers

High-level occupational manganese (Mn) exposure has been reported to induce irreversible brain alterations determining a Parkinson-like disease. This study aimed to assess subclinical neurophysiological alterations in welding workers. They were employed in a machine building factory with an average Mn exposure <200 mg/m3. Sixty-eight welding workers (mean age: 34 years; mean Mn exposure duration: 16 years) and 42 flour factory workers (control group) with similar age and smoking habit were recruited. Autonomic nervous function test battery (ANSFT), composed of Valsalva maneuvre-induced heart rate variation (HR-V), heart rate variation following deep breathing (HR-DB) and heart rate variation following immediate standing up (HR-IS) was assessed. Electroencephalogram (EEG), brain electricity activity mapping (BEAM) were also performed. HR-V, HR-DB and HR-IS were significantly lower in Mn- exposed subjects showing altered autonomic nervous system activity, parasympathetic-sympathetic imbalance and, consequently, altered cardiovascular regulation and reactivity. The EEG of the Mn-exposed workers evidenced β-wave rhythms significantly reduced, Θ-waves markedly increased and abnormal wave activities of either localized or diffusive type. In the same workers, BEAM revealed higher Θ, δ and β power values in the F7 area, lower d power values in the FP1, FP2 and C4 areas as well as dissymmetry in the central area, parietal region and occipital region. This study suggests that Mn impairs neuron activity within central nervous system. In this context, brainstem parasympathetic and sympathetic centers, receiving axon projections from cortical and diencephalic areas, may reflect Mn effects on upper pathways. However, direct actions of Mn on these centers cannot be excluded.

Neurobehavioral Functions, Serum Prolactin and Plasma Renin Activity of Manganese-Exposed Workers

Objective of this study was to assess effects of manganese (Mn) exposure on 56 workers employed in a Mn welding workshop of a machine building factory in Taiyuan (Shanxi Province, P.R. China) for a mean period of 16.1 years. The mean air Mn level in the workshop was 138.4 μg/m3. Neurobehavioral Core Test Battery (NCTB), including the Profile of Mood States (POMS), was performed. Blood pressure (BP) increase following immediate stand-up (BP-IS), serum prolactin (PRL) and plasma renin activity (PRA) in supine position were also determined. Most of the NCTB scores of the Mn-exposed workers were lower than those of the controls, while the POMS scores were higher, indicating a Mn-induced impairment of neurophysiological functions and a deflection of mood towards negative emotion states. PRL values of the Mn-exposed workers were higher than those of the controls. BP-IS of Mn-exposed workers was significantly lower than that of the controls. PRA of the same workers was augmented more than 200 %. In the Mn-exposed workers, the higher PRL values are possibly due to a reduced inhibitory effect on pituitary lactotrope cells by the tubero-infundibular dopamine system; the decreased BP-IS was referred to imbalance between the sympathetic and parasympathetic activities, whereas the higher basal PRA was thought to depend on neuroendocrine changes (including increased central sympathetic tone) and/or on a direct effect of Mn on renal juxta-glomerular cells. On the whole, this study demonstrates that occupational Mn exposure is responsible for neurobehavioral changes coexisting with alterations of neuroendocrine and humoral systems.

Association of APOA1 gene polymorphisms (rs670, rs5069, and rs2070665) with dyslipidemia in the Kazakhs of Xinjiang

The aim of this study was to investigate the potential association between apolipoprotein A1 (APOA1) gene rs670, rs5069, and rs2070665 polymorphisms and dyslipidemia in the Kazakh population of Xinjiang, China. Matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF-MS) was used to identify APOA1 (rs670, rs5069, and rs2070665) genotypes in 736 subjects (341 dyslipidemia patients and 395 control subjects). The frequencies of the CC genotype for rs1421085 were found to be 7.2% (obese group), 4.4% (overweight group), and 5.6% (control group). Polymorphisms of the three loci of the APOA1 gene in Kazakh subjects met Hardy-Weinberg equilibrium. The frequencies of the A allele for rs670 were found to be 14.3% (dyslipidemia group) and 12.7% (control group). The frequencies of the T allele for rs5069 and rs2070665 were: dyslipidmia group (7.2 and 30.1%, respectively) and control group (7.7 and 32.5%, respectively). Frequency distributions of the 3 types of genotypes and alleles of the three loci showed no statistically significant difference (P > 0.05). Significant differences were observed in lipoprotein (α) [Lp(α)] between patients with the rs2070665 CT + TT and CC genotypes (P < 0.05); however, none of the other relevant indicators differed significantly between the two genotypes. No significant association was identified between rs670 or rs5069 and the lipid-related metabolic indices assessed in the study. These findings indicate that the polymorphisms in the APOA1 gene (rs670, rs5069, and rs2070665) are not associated with dyslipidemia in the Kazakh population assessed in this study.

[Aluminuminduced impairment in primary cultured rat choroid plexus epithelial cells]

OBJECTIVE

To investigate the impairment in primary cultured rat choroid plexus epithelial cells (CPECs)induced by aluminum.

METHODS

The choroid plexus isolated from Sprague-Dawley rats 14 days old was cut into pieces and digested by trypsin in the sterile area. The obtained single cells were cultured in DMEM with 1% epidermal growth factor and 20% fetal calf serum. Five days later, immunohistochemistry with anti-transthyretin antibody was used to identify the purity of cultured cells. The well-grown cells were treated with aluminum lactate at different concentrations (0, 100, 400, and 1 600 μmol/L for control, lowdose, mediumdose, and highdose groups). Fortyeight hours later, the cell viability, apoptotic rate, level of reactive oxygen species (ROS), and activity of superoxide dismutase (SOD)were measured in each group to evaluate the impairment in primary cultured rat CPECs by aluminum.

RESULTS

More than 95% of the cultured cells were identified as CPECs. The medium-and high-dose groups had significantly lower cell viability than the control group(86.74%±4.03% vs 100%, P<0.01; 81.90%±9.17% vs 100%, P<0.01). The high-dose group had significantly lower cell viability than the lowdose group (81.90%±9.17% vs 92.92%±8.81%, P<0.01). The medium-and high-dose groups had significantly higher apoptotic rates than the control group (7.26%±0.99% vs 1.29%±0.03%, P<0.01; 22.25%±1.55% vs 1.29%±0.03%, P<0.01)and the low-dose group (7.26%±0.99% vs 1.68%±0.27%, P<0.01; 22.25%±1.55% vs 1.68%±0.27%, P<0.01). The high-dose group had a significantly higher apoptotic rate than the medium-dose group (22.25%±1.55% vs 7.26%±0.99%, P<0.01). The mediumand high-dose groups had significantly higher fluorescence intensity of ROS than the control group (22.23%±0.41% vs 17.24%±0.09%, P<0.05; 25.10%±1.13% vs 17.24%±0.09%, P<0.05)and the lowdose group (22.23%±0.41% vs 18.31%±0.21%, P<0.05; 25.10%±1.13% vs 18.31%±0.21%, P<0.05). The highdose group had significantly higher fluorescence intensity of ROS than the mediumdose group (25.10%±1.13% vs 22.23%±0.41%, P< 0.05). The low-, medium-and high-dose groups had significantly lower SOD activity than the control group[(28.65±0.74)U/g Hb vs (37.35±1.05)U/g Hb, P<0.05; (22.75±1.94)U/g Hb vs (37.35±1.05)U/g Hb, P<0.05; (13.29±0.64)U/g Hb vs(37.35±1.05)U/g Hb, P<0.05]. The medium-and high-dose groups had significantly lower SOD activity than the low-dose group[(22.75±1.94)U/g Hb vs(28.65±0.74)U/g Hb, P<0.05; (13.29±0.64)U/g Hb vs (28.65±0.74)U/g Hb, P<0.05], while the high-dose group had had significantly lower SOD activity than the medium-dose group[(13.29±0.64)U/g Hb vs (22.75±1.94)U/g Hb, P<0.05]. There were no significant differences in cell viability, apoptotic rate, level of ROS, or activity of SOD between any other two groups (P>0.05).

CONCLUSION

Aluminum lactate may induce impairment in primary cultured rat CPECs. It reduces the cell viability, elevates the apoptotic rate, and causes oxidative stress.

[Effects of subchronic aluminum lactate exposure on learning and memory and transportation of Aβ in blood-cerebrospinal fluid in rats]

OBJECTIVE

To investigate the effects of aluminum lactate exposure on learning and memory and the transportation of amyloid-beta peptides(Aβ) in cerebrospinal fluid in rats.

METHODS

A total of 80 male Sprague-Dawley rats were randomly divided into solvent control(distilled water) group and low-, medium-, and high-dose aluminum poisoning groups(10, 30, and 90 mg/kg aluminum lactate), with 20 rats in each group, and the poisoning procedure was performed by gavage for 2 months. The Morris water maze test was used to test the rats' learning and memory, Western blot was used to measure the expression level of low-density lipoprotein receptor protein-1(LRP-1) in rats' choroid plexus, and enzyme-linked immunosorbent assay(ELISA) was used to measure the content of Aβ in the cerebrospinal fluid and plasma.

RESULTS

The Morris water maze test showed that in the place navigation test, with the increasing training time, the escape latency was significantly shortened in each group and showed significant differences between any two groups(P<0.05). In the spatial probe test, the time spent in target quadrant in the medium-and high-dose groups was 11.52±1.56 s and 10.43±5.27 s, respectively, which was significantly shorter than that in the control group and the low-dose group(15.81±3.01 s and 13.91±2.17 s)(P<0.05). The numbers of platform crossings in the medium-and high-dose groups were 2.64±1.39 and 1.50±0.76, respectively, which were significantly lower than those in the control group and the low-dose group(4.29±0.914 and 3.56±1.38)(P<0.05). The results of ELISA showed that the medium-and high-dose groups had significant increases in the content of Aβ1-42 in cerebrospinal fluid(320.35±84.82 pg/ml and 327.68±67.51 pg/ml), which was significantly higher than that in the control group(203.46±74.36 pg/ml) (P<0.05). The content of Aβ1-42 in plasma showed no significant difference between any two groups(P>0.05), and that of Aβ1-40 in cerebrospinal fluid and plasma also showed no significant difference between any two groups(P>0.05). The results of Western blot showed that the high-dose group had significantly lower protein expression of LRP-1 than the control group and the low-and medium-dose groups(0.57±0.21 vs 1.00±0.00/0.79±0.15/0.95±0.24, P<0.05).

CONCLUSION

Subchronic aluminum exposure may reduce learning and memory in rats, and the accumulation of Aβ in cerebrospinal fluid may be related to the reduced protein expression of LRP-1 in the choroid plexus, suggesting that aluminum affects learning and memory in rats through reducing the protein expression of LRP-1, influencing the transportation of Aβ, and leading to the accumulation of Aβ.

Association between polymorphisms of fat mass and obesity-associated gene and metabolic syndrome in Kazakh adults of Xinjiang, China

The aim of this study was to assess the association between three FTO polymorphisms (rs9939609, rs8057044, and rs1421085) and metabolic syndrome (MS)-related outcomes in the low-income, rural, nomadic minority Khazakh population in far western China. A total of 489 subjects (245 MS patients, 244 controls) were included in the study and DNA samples were genotyped for the three polymorphisms by matrix-assisted laser desorption/ionization time of flight mass spectrometry. The frequencies of the rs1421085 and rs9939609 genotypes and alleles did not differ significantly between MS patients and control, while the frequencies of rs8057044 G alleles and GG genotypes were higher in MS patients (P < 0.05) than in control subjects (G: 61.16 vs 53.53%, GG: 39.07 vs 29.05%) and the frequencies of rs8057044 A genotypes and alleles were lower (P < 0.05) in MS patients compared with controls (AA: 17.36 vs 21.99%, A: 38.84 vs 46.47%). Risk analysis of the rs8057044 polymorphism revealed individuals with GA and GG genotypes to have 1.112 and 1.731 times higher risks of developing MS than those with the AA genotype, respectively, while the G allele was found to be associated with a 1.367 times higher risk of developing MS compared with the A allele. These apparent correlations, however, did not hold true when adjusted for BMI. Weight, WC, HC, and BMI differed significantly between rs8057044 GG and AA+GA genotypes (P < 0.05).

Lutein alleviates arsenic-induced reproductive toxicity in male mice via Nrf2 signaling

This study aims to investigate the mechanisms involved in the action of lutein (LU) alleviating arsenic-induced reproductive toxicity using mice model. Forty male Kunming mice were received following treatments by gavage: normal saline solution (control), arsenic trioxide (ATO; 5 mg/kg/day), LU (40 mg/kg/day), and ATO + LU (5 mg/kg/day + 40 mg/kg/day). At the end, the mice were killed by cervical dislocation and weighed. Pathological examination was done on the testis. The biomedical parameters including superoxide dismutase (SOD), glutathione (GSH), total antioxidative capability, malondialdehyde (MDA), 8-hydroxydeoxyguanosine (8-OHdG), and reproductive indexes were analyzed. The messenger RNA (mRNA) and protein expression of Nrf2, heme oxygenase 1 (HO-1), glutathione S-transferase (GST), nicotinamide adenine dinucleotide phosphate dehydrogenase, quinone 1 (NQO1) in testis were detected by real-time polymerase chain reaction and Western blot. We found that there was a decrease in sperm count; testis somatic index; the activities of SOD, GSH, total antioxidative capacity ( p < 0.01, respectively) in ATO-treated mice, while there was an increase in the levels of sperm abnormalities, MDA, and 8-OHdG than control ( p < 0.01, respectively). The groups treated with ATO + LU showed recovery of the measured parameters between those of ATO or saline-treated group. The antagonized interaction between ATO and LU was statistically significant ( p < 0.01). Mice treated with ATO + LU also showed greater mRNA expression of Nrf2, HO-1, NQO1, and GST than ATO or saline-treated groups. These findings suggest that LU alleviates reproductive toxicity induced by arsenic in male mice via Nrf2 signaling, which implicates a possible mechanism of LU in preventing the reproductive injury, and elucidates that consuming the rich plant sources of LU will alleviate the reproductive toxicity induced by chemicals.

Epidemiological characteristics of motor neuron disease in Chinese patients

BACKGROUND

The epidemiology, diagnosis, and treatment of motor neuron disease (MND) in Chinese patients are ill known.

METHODS

A registered study of 461 MND patients was conducted across 10 facilities in 7 Chinese cities from February 2009 to March 2010.

RESULTS

Patients were classified as amyotrophic lateral sclerosis (ALS) (84.4%), progressive bulbar palsy (PBP) (4.1%), progressive muscular atrophy (PMA) (10.4%), or primary lateral sclerosis (PLS) (0.9%). MND was predominant in men (men/women; 1.6:1.0). Mean onset age was 52.6 years, with the highest incidence being observed between 51 and 60 years. Notably, 26.0% of MND patients were employed in forestry, fishery, or animal husbandry industries. Ten cases (2.7%) reported family history of MND, and 54.2% exhibited cervical onset. MND was also associated with head/neck trauma. Non-invasive positive pressure ventilation was the most common supportive therapy.

CONCLUSION

As a novel comprehensive report of a Chinese population, this study reveals that epidemiological characteristics of MND patients were similar to those observed in international populations. MND is age-related, male gender predominant, and may be associated with both environmental and genetic risk factors.

Methylation of CpG island of p14(ARK), p15(INK4b) and p16(INK4a) genes in coke oven workers

To detect the blood genomic DNA methylation in coke oven workers and find a possible early screening index for occupational lung cancer, 74 coke oven workers as the exposed group and 47 water pump workers as the controls were surveyed, and urine samples and peripheral blood mononuclear cells (PBMCs) were collected. Airborne benzo[a]pyrene (B[a]P) levels in workplace and urinary 1-hydroxypyrene (1-OH-Py) levels were determined by high-performance liquid chromatography. DNA damage of PBMCs and the p14(ARK), p15(INK4b) and p16(INK4a) gene CpG island methylation in the promoter region were detected by comet assay and methylation-specific polymerase chain reaction techniques, respectively. Results show that compared with the controls, concentration of airborne B[a]Ps was elevated in the coke plant, and urinary 1-OH-Py's level and DNA olive tail moment in comet assay were significantly increased in the coke oven workers, and p14(ARK), p15(INK4b) and p16(INK4a) gene methylation rates were also significantly increased. With the working years and urinary 1-OH-Py's level, the rates of p14(ARK) and p16(INK4a) gene methylation were significantly increased while that of p15(INK4b) gene methylation displayed no statistical change. We conclude that PBMCs' p14(ARK) and p16(INK4a) gene methylation may be used for screening and warning lung cancer in coke oven workers.

Epidemiological analysis of dyslipidemia in adults of three ethnicities in Xinjiang, China

This study investigated the prevalence and distribution of dyslipidemia in adults of Uygur, Kazak, and Han ethnicity in Xinjiang, China. A questionnaire including general data, physical examination (blood pressure, body height, and body weight) and blood lipid [total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C)] was administered to 11,506 adults in Xinjiang, China from 2009 to 2010 using a stratified sampling method. The overall prevalence rates of dyslipidemia in Uygur, Kazak, and Han adults were 42.4, 31.6, and 30.2%, respectively; they were 42.4, 31.8, and 28.2% after age standardization (P < 0.01). After standardization, the overall prevalence rates in Uygur, Kazak, and Han men were 52.6, 35.4, and 33.2%, respectively, which were significantly higher than that in women of the corresponding ethnicities (P < 0.01). In Uygur, Kazak, and Han adults, there were significant differences with respect to the standardized prevalence rates of high TG (9.3, 9.3, and 17.3%), high TC (5.2, 6.9, and 6%), low HDL-C (33.6, 20.8, and 11.1%), and high LDL-C (2.4, 2.9, and 2%) (P < 0.05). The prevalence rates of dyslipidemia in Uygur, Kazak, and Han adults in Xinjiang are higher than the average levels in China, with significant differences in ethnicity, age, and gender. Han adults exhibited the highest prevalence rate of high TG. Meanwhile, Uygur adults had the highest prevalence rate of low HDL-C. Kazak adults had high prevalence rates of high TC, low HDL-C, and high LDL-C.

Involvement of mitochondrial pathway in benzo[a]pyrene-induced neuron apoptosis

Benzo[a]pyrene (B[a]P), a well-known carcinogen, is widespread in the environment. Although the neurotoxic effect of B[a]P has not drawn much attention, toxic effects of B[a]P on learning and memory have been reported. Since it is well known that neuronal apoptosis plays a major role in impairment of learning and memory triggered by many stimuli, an effort has been made to examine whether the B[a]P-induced neurotoxicity occurs through mitochondria-mediated apoptosis. Cultured newborn rat cerebral neurons were used to clarify the apoptosis induced by B[a]P in the study. After incubating with different doses of B[a]P in presence of S9 for 40 h, the apoptotic rates of B[a]P-treated neurons increased in a dose-dependent manner. Further analysis showed that B[a]P-induced apoptosis was accompanied by loss of mitochondrial membrane potential, release of cytochrome c from mitochondria to the cytosol, downregulation of antiapoptotic protein B-cell lymphoma-2 (Bcl-2) levels with concurrent upregulation in proapoptotic Bcl-2-associated X protein (Bax) levels, and increase in the levels and activities of caspases-9 and -3. However, there was no difference in the activity of caspase-8 between B[a]P-exposed neurons and controls. Collectively, these results showed that B[a]P upregulates Bax and downregulates Bcl-2 expression in cultured cerebral neurons, which leads to mitochondrial release of cytochrome c, caspase-3 activation and neuronal apoptotic death.

Residual Wall Thickness Study of Variable Cross-section Tube in Water-assisted Injection Molding

Residual wall thickness is an important measure of the quality of water-assisted injection molding (WAIM) parts. Based on the traditional injection molding model, Reynolds stress was introduced into the WAIM model for the turbulent characteristics of high pressure water. In addition, residual wall thickness was computed by a computational fluid dynamics (CFD) method, and the results matched well with experimental data. The results show that the hollowed core ratio changes from small to large in the first half of water penetration, while in the latter half it is just the opposite. Difference of the residual wall thickness is larger at the large-diameter position of a part than other position. Residual wall thickness is mainly affected by water injection pressure, delay time, melt temperature, mold temperature and amount of short shot, in which the amount of short shot is the most obvious.

Lysosomes involved in the cellular toxicity of nano-alumina: combined effects of particle size and chemical composition

Nowadays, manufactured nano-particles of aluminum oxide (nano-alumina) have been widely used in many fields with the rapidly developed nano-technology, but their basic toxic data are scarce. It is believed that the smaller nano-particles are able to easily cross the bio-membrane and quickly reach cellular compartments rather than micro-size particles, thus showing more toxic effects. The aim of this study was to compare the toxicity of nano- and micro- particles of alumina for detecting particle size related toxicity, and to compare the toxicity of nano-alumina and nano-carbon with the same particle size for determining chemical composition related toxicity. The present study revealed that nano-particles of alumina were much toxic than micro-alumina particles, indicating a particle size related toxicity; and were much more toxic than nano-carbon particles as well, manifesting a chemical related toxicity. The mechanism might be concerned with the involvement of the lysosomes. In conclusion, toxicity of nano-alumina is a combination of the toxic effects of its particle size and chemical composition.

Development and application of a loop-mediated isothermal amplification assay for rapid detection of Borrelia burgdorferi s. l. in ticks

A loop-mediated isothermal amplification (LAMP) assay was developed to detect Borrelia burgdorferi s. l. in ticks, which is a pathogen that causes Lyme disease. Cross-reactions with Chlamydia psittaci, Mycoplasma mycoides subsp. capri and some tick-borne pathogens were excluded. Analytical sensitivity of LAMP showed its detection limit was from 0.02 to 0.2 pg of DNA in detection of the reference samples at 65°C for 40 min. The performance of LAMP was assessed by testing 110 samples from susceptible tick species and comparing the results with conventional and nested PCR tests previously described. The results demonstrated that LAMP was significantly more sensitive than the conventional PCR (32.7% versus 15.5%, P < 0.05) and slightly more sensitive, although not significantly so, than nested PCR (32.7% versus 26.4%, P > 0.05). The assay was used to analyse a total of 1052 ticks collected from eight provinces in China. The results showed that the infection rates of B. burgdorferi s. l. varied from 12.5% to 88.9% across the different geographical sites. Selected positive samples were subjected to sequencing and sequence analysis for conformation of the accuracy of the assay. Here we report a highly sensitive, specific and easy diagnostic assay based on LAMP technology. These data indicate that LAMP is a useful approach for detecting B. burgdorferi s. l. in field-collected ticks and has the potential as an alternative tool for the ecological and epidemiological surveillance of Lyme disease.

Perceived parenting and risk for major depression in Chinese women

BACKGROUND

In Western countries, a history of major depression (MD) is associated with reports of received parenting that is low in warmth and caring and high in control and authoritarianism. Does a similar pattern exist in women in China?

METHOD

Received parenting was assessed by a shortened version of the Parental Bonding Instrument (PBI) in two groups of Han Chinese women: 1970 clinically ascertained cases with recurrent MD and 2597 matched controls. MD was assessed at personal interview.

RESULTS

Factor analysis of the PBI revealed three factors for both mothers and fathers: warmth, protectiveness, and authoritarianism. Lower warmth and protectiveness and higher authoritarianism from both mother and father were significantly associated with risk for recurrent MD. Parental warmth was positively correlated with parental protectiveness and negatively correlated with parental authoritarianism. When examined together, paternal warmth was more strongly associated with lowered risk for MD than maternal warmth. Furthermore, paternal protectiveness was negatively and maternal protectiveness positively associated with risk for MD.

CONCLUSIONS

Although the structure of received parenting is very similar in China and Western countries, the association with MD is not. High parental protectiveness is generally pathogenic in Western countries but protective in China, especially when received from the father. Our results suggest that cultural factors impact on patterns of parenting and their association with MD.

Simultaneous detection of piroplasma infections in field Haemaphysalis qinghaiensis ticks by reverse line blotting

Piroplasmosis is caused by tick-borne haemoprotozoan parasites in the genera of Theileria and Babesia, in which numbers of agents are highly pathogenic for cattle, sheep and goats. We developed a reverse line blot (RLB) assay for detection and differentiation of four different parasites, in which 18S ribosomal RNA gene sequence was amplified with a set of universal primers specific for all members in the genera of Theileria and Babesia; and the probes were designed on the basis of hypervariable region 4 (V4 region) of 18S rRNA gene. Three Theileria and one Babesia can be detected simultaneously on this system and it was sensitive to detect a parasitemia level between 10(-5) and 10(-8)%. A total of 149 Haemaphysalis qinghaiensis ticks collected from Lintan County of Gannan Tibetan Autonomous Region was tested by RLB. Among these, 136 tick samples were also tested by a nested PCR assay developed previously. After comparison of these results, it showed that more T. luwenshuni was detected in RLB assay, while more T. uilenbergi was detected in H. qinghaiensis ticks by nested PCR. The RLB has shown capability for simultaneous detection of four species of piroplasm in H. qinghaiensis ticks, indicating its usefulness for epidemiological studies of piroplasmosis.

APP/PS1 Transgenic Mice Treated with Aluminum: An Update of Alzheimer's Disease Model

There is still no animal model available that can mimic all the cognitive, behavioral, biochemical, and histopathological abnormalities observed in patients with Alzheimer's disease (AD). We undertook to consider the interaction between genetic factors, including amyloid precursor protein (APP) and presenilin-1 (PS1), and environmental factors, such as Aluminum (Al) in determining susceptibility outcomes when studying the pathogenesis of AD. In this article, we provide an AD model in APP/PS1 transgenic mice triggered by Al. The animal model was established via intracerebral ventricular microinjection of aluminum chloride once a day for 5 days in APP/PS1 transgenic mice. Twenty wild type (WT) mice and 20 APP/PS1 transgenic (TG) mice were separately divided into 2 groups (control and Al group), and a stainless steel injector with stopper was used for microinjection into the left-lateral cerebral ventricle of each mouse. The Morris water maze task was used to evaluate behavioral function of learning and memory ability on the 20th day after the last injection. This AD model's brain was analyzed by: (1) amyloid β immunohistochemical staining; (2) Tunnel staining; (3) apoptotic rates; (4) caspase-3 gene expression. Here, decrease of cognitive ability and neural cells loss were shown in APP/PS1 transgenic mice exposed to Al, which were more extensive than those in APP/PS1 TG alone and WT mice exposed to Al alone. These findings indicate that there is a close relationship between over-expression of APP and PS1 genes and Al overload. It is also suggested that APP/PS1 TG mice exposed to Al have potential value for improving AD models.