Modulating plant-soil microcosm with green synthesized ZnONPs in arsenic contaminated soil

Biogenic nanoparticle (NP), derived from plant sources, is gaining prominence as a viable, cost-effective, sustainable, and biocompatible alternative for mitigating the extensive environmental impact of arsenic on the interplay between plant-soil system. Herein, the impact of green synthesized zinc oxide nanoparticles (ZnONPs) was assessed on Catharanthus roseus root system-associated enzymes and their possible impact on microbiome niches (rhizocompartments) and overall plant performance under arsenic (As) gradients. The application of ZnONPs at different concentrations successfully modified the arsenic uptake in various plant parts, with the root arsenic levels increasing 1.5 and 1.4-fold after 25 and 50 days, respectively, at medium concentration compared to the control. Moreover, ZnONPs gradients regulated the various soil enzyme activities. Notably, urease and catalase activities showed an increase when exposed to low concentrations of ZnONPs, whereas saccharase and acid phosphatase displayed the opposite pattern, showing increased activities under medium concentration which possibly in turn influence the plant root system associated microflora. The use of nonmetric multidimensional scaling ordination revealed a significant differentiation (with a significance level of p < 0.05) in the structure of both bacterial and fungal communities under different treatment conditions across root associated niches. Bacterial and fungal phyla level analysis showed that Proteobacteria and Basidiomycota displayed a significant increase in relative abundance under medium ZnONPs concentration, as opposed to low and high concentrations, respectively. Similarly, in depth genera level analysis revealed that Burkholderia, Halomonas, Thelephora and Sebacina exhibited a notably high relative abundance in both the rhizosphere and rhizoplane (the former refers to the soil region influenced by root exudates, while the latter is the root surface itself) under medium concentrations of ZnONPs, respectively. These adjustments to the plant root-associated microcosm likely play a role in protecting the plant from oxidative stress by regulating the plant's antioxidant system and overall biomass.

Deep medullary vein damage correlates with small vessel disease in small vessel occlusion acute ischemic stroke

OBJECTIVES

We aim to investigate whether cerebral small vessel disease (cSVD) imaging markers correlate with deep medullary vein (DMV) damage in small vessel occlusion acute ischemic stroke (SVO-AIS) patients.

METHODS

The DMV was divided into six segments according to the regional anatomy. The total DMV score (0-18) was calculated based on segmental continuity and visibility. The damage of DMV was grouped according to the quartiles of the total DMV score. Neuroimaging biomarkers of cSVD including white matter hyperintensity (WMH), cerebral microbleed (CMB), perivascular space (PVS), and lacune were identified. The cSVD score were further analyzed.

RESULTS

We included 229 SVO-AIS patients, the mean age was 63.7 ± 23.1 years, the median NIHSS score was 3 (IQR, 2-6). In the severe DMV burden group (the 4th quartile), the NIHSS score grade (6 (3-9)) was significantly higher than other groups (p < 0.01). The grade scores for basal ganglia PVS (BG-PVS) were positively correlated with the degree of DMV (R = 0.67, p < 0.01), rather than centrum semivole PVS (CS-PVS) (R = 0.17, p = 0.1). In multivariate analysis, high CMB burden (adjusted odds ratio [aOR], 25.38; 95% confidence interval [CI], 1.87-345.23) was associated with severe DMV scores. In addition, BG-PVS was related to severe DMV burden in a dose-dependent manner: when BG-PVS score was 3 and 4, the aORs of severe DMV burden were 18.5 and 12.19, respectively.

CONCLUSION

The DMV impairment was associated with the severity of cSVD, which suggests that DMV burden may be used for risk stratification in SVO-AIS patients.

CLINICAL RELEVANCE STATEMENT

The DMV damage score, based on the association between small vessel disease and the deep medullary veins impairment, is a potential new imaging biomarker for the prognosis of small vessel occlusion acute ischemic stroke, with clinical management implications.

KEY POINTS

• The damage to the deep medullary vein may be one mechanism of cerebral small vessel disease. • Severe burden of the basal ganglia perivascular space and cerebral microbleed is closely associated with significant impairment to the deep medullary vein. • The deep medullary vein damage score may reflect a risk of added vascular damage in small vessel occlusion acute ischemic stroke patients.

Comprehensive review: Effects of climate change and greenhouse gases emission relevance to environmental stress on horticultural crops and management

Global climate change exerts a significant impact on sustainable horticultural crop production and quality. Rising Global temperatures have compelled the agricultural community to adjust planting and harvesting schedules, often necessitating earlier crop cultivation. Notably, climate change introduces a suite of ominous factors, such as greenhouse gas emissions (CGHs), including elevated temperature, increased carbon dioxide (CO2) concentrations, nitrous oxide (N2O) and methane (CH4) ozone depletion (O3), and deforestation, all of which intensify environmental stresses on crops. Consequently, climate change stands poised to adversely affect crop yields and livestock production. Therefore, the primary objective of the review article is to furnish a comprehensive overview of the multifaceted factors influencing horticulture production, encompassing fruits, vegetables, and plantation crops with a particular emphasis on greenhouse gas emissions and environmental stressors such as high temperature, drought, salinity, and emission of CO2. Additionally, this review will explore the implementation of novel horticultural crop varieties and greenhouse technology that can contribute to mitigating the adverse impact of climate change on agricultural crops.

A machine-learning approach based on multiparametric MRI to identify the risk of non-sentinel lymph node metastasis in patients with early-stage breast cancer

BACKGROUND

It has been reported that patients with early breast cancer with 1-2 positive sentinel lymph nodes have a lower risk of non-sentinel lymph node (NSLN) metastasis and cannot benefit from axillary lymph node dissection.

PURPOSE

To develop the potential of machine learning based on multiparametric magnetic resonance imaging (MRI) and clinical factors for predicting the risk of NSLN metastasis in breast cancer.

MATERIAL AND METHODS

This retrospective study included 144 patients with 1-2 positive sentinel lymph node breast cancer. Multiparametric MRI morphologic findings and the detailed demographical characteristics of the primary tumor and axillary lymph node were extracted. The logistic regression, support vector classification, extreme gradient boosting, and random forest algorithm models were established to predict the risk of NSLN metastasis. The prediction efficiency of a machine-learning-based model was evaluated. Finally, the relative importance of each input variable was analyzed for the best model.

RESULTS

Of the 144 patients, 80 (55.6%) developed NSLN metastasis. A total of 24 imaging features and 14 clinicopathological features were analyzed. The extreme gradient boosting algorithm had the strongest prediction efficiency with an area under curve of 0.881 and 0.781 in the training set and test set, respectively. Five main factors for the metastasis of NSLN were found, including histological grade, cortical thickness, fatty hilum, short axis of lymph node, and age.

CONCLUSION

The machine-learning model incorporating multiparametric MRI features and clinical factors can predict NSLN metastasis with high accuracy for breast cancer and provide predictive information for clinical protocol.

MRI Assessment of Brain Frailty and Clinical Outcome in Patients With Acute Posterior Perforating Artery Infarction

BACKGROUND

Global brain health has gained increasing attention recently. Imaging markers of brain frailty have been related to functional outcomes in previous studies on anterior circulation; however, little data are available on imaging markers and posterior circulation.

PURPOSE

To investigate the impact of brain frailty on functional outcomes in patients with acute perforating artery infarction (PAI) of the posterior circulation.

STUDY TYPE

Prospective.

POPULATION

One hundred patients (60.78 ± 9.51 years, 72% men) with acute posterior circulation PAI (determined by diffusion-weighted magnetic resonance imaging (MRI)/time-of-flight MR angiography).

FIELD STRENGTH/SEQUENCE

T1- and T2-weighted fast spin echo, T2-weighted fluid-attenuated inversion recovery, diffusion-weighted echo planar, gradient echo (susceptibility-weight imaging), and 3D time-of-flight MR angiography sequences at 3.0 T.

ASSESSMENT

Periventricular and deep white matter hyperintensities (WMH), enlarged perivascular spaces (EPVS) in the basal ganglia and centrum semiovale area, lacunes, cerebral microbleeds (CMB), and total brain frailty score by calculating the above imaging characters were rated visually by three radiologists with 9, 10, and 11 years of experience and one neuroradiologist with 12. Infarction volume was assessed using baseline diffusion-weighted imaging (DWI) data obtained within 24 hours of symptom onset. A modified Rankin Scale (mRS) score >1 on day 90 defined an adverse functional outcome. Associations between the imaging markers of brain frailty and functional outcomes were assessed.

STATISTICAL TESTS

Fisher's exact test, Mann-Whitney U test, and multivariable binary logistic regression. A P value <0.05 was considered statistically significant.

RESULTS

Adverse prognoses (mRS > 1) were observed in 34 (34%) patients. Infarction volume, periventricular WMH, deep WMH, basal ganglia EPVS, CMB, and the brain frailty score were significantly associated with adverse functional outcomes. An increased brain frailty score was significantly associated with unfavorable mRS score on day 90 (odds ratio 1.773, 95% confidence interval 1.237-2.541).

DATA CONCLUSION

Advanced MRI imaging markers of brain frailty, individually or combined as a total brain frailty score, were associated with worse functional outcomes after acute posterior circulation PAI.

LEVEL OF EVIDENCE

3 TECHNICAL EFFICACY: Stage 3.

[Hsp90 participates in the necroptosis of mouse neural cells induced by aluminum through the RIP1/RIP3/MLKL pathway]

Objective: To investigate whether heat shock protein 90 (HSP90) participates in the necroptosis of C57BL/6 mouse neurons and spatial memory impairment induced by Aluminum maltol [Al (mal) (3)] through RIP1/RIP3/MLKL pathway. Methods: In March 2022, Thirty-two C57 mice were randomly divided into control group, Low dose group, a medium dose group, and a high-dose group, with 8 mice in each group, and injected intraperitoneally with physiological saline, 20, 40, and 80, respectivelyμmol/kgAl (mal) (3) was administered, it was injected 5 days a week and discontinued 2 days for 60 days. Morris water maze test was used to test the spatial learning and memory ability of mice. Nissl staining was used to observe the pathological changes of brain tissue. The protein expression levels of RIP1, RIP3, MLKL and HSP90 in hippocampus were determined by Western blotting. Results: In the water maze experiment, compared with the control group, the number of mice crossing the platform decreased in each dose group, the difference was statistically significant (H=9.50, P=0.023), and the number of mice crossing the platform was statistically significant among each dose group (P <0.05). Compared with the control group, the number of hippocampal nerve cells in each dose group decreased, the arrangement was disordered, and the Nissellite bodies decreased. Western blotting results showed that compared with the control group, the expression level of RIP1 protein in the hippocampus of mice in high-dose group was higher, and the difference was statistically significant (P <0.05). The expression levels of RIP3, MLKL and HSP90 in hippocampal tissue of mice in medium and high dose groups were increased, and the differences were statistically significant (P<0.05). After siRNA intervention decreased the expression of HSP90 protein, the expressions of HSP90, RIP1, RIP3 and MLKL in Al (mal) (3) groups were increased, and the differences were statistically significant (P<0.05) . Conclusion: Through RIP1/RIP3/MLKL pathway, HSP90 is involved in neuronal programmed necrosis and spatial memory impairment induced by maltol aluminum in C57 mice.

Integrated Analysis of the Transcriptome and Metabolome of Brassica rapa Revealed Regulatory Mechanism under Heat Stress

Affected by global warming; heat stress is the main limiting factor for crop growth and development. Brassica rapa prefers cool weather, and heat stress has a significant negative impact on its growth, development, and metabolism. Understanding the regulatory patterns of heat-resistant and heat-sensitive varieties under heat stress can help deepen understanding of plant heat tolerance mechanisms. In this study, an integrative analysis of transcriptome and metabolome was performed on the heat-tolerant ('WYM') and heat-sensitive ('AJH') lines of Brassica rapa to reveal the regulatory networks correlated to heat tolerance and to identify key regulatory genes. Heat stress was applied to two Brassica rapa cultivars, and the leaves were analyzed at the transcriptional and metabolic levels. The results suggest that the heat shock protein (HSP) family, plant hormone transduction, chlorophyll degradation, photosynthetic pathway, and reactive oxygen species (ROS) metabolism play an outstanding role in the adaptation mechanism of plant heat tolerance. Our discovery lays the foundation for future breeding of horticultural crops for heat resistance.

[Effect of miR-96-5p targeting IRS1 on apoptosis of PC12 cells induced by aluminum maltol]

Objective: To investigate the effect and mechanism of miR-96-5p on apoptosis of PC12 cells induced by maltol aluminum. Methods: In January 2021, PC12 cells at logarithmic growth phase were divided into blank control group and low, medium and high dose group. Cells in each group were treated with 0, 100, 200 and 400 μmol/L maltol aluminum for 24 hours respectively. Cells were collected and cell apoptosis rates were detected by flow cytometry, miR-96-5p and insulin receptor substrate 1 (IRS1) mRNA expressions were detected by qRT-PCR, and the protein expression levels of cysteine protease 3 (Caspase3) 、activated cysteine protease 3 (Cleaved-caspase3) 、IRS1、phosphorylated protein kinase B (p-AKT) and phosphorylated glucose synthesis kinase 3β (p-GSK3β) were detected by western blotting. The target binding relationship between miR-96-5p and IRS1 was detected by double luciferase reporter gene experiment. The miR-96-5p inhibitor cells and negative control cells were constructed after transfecting PC12 cells with miR-96-5p inhibitor for 24 hours. The cells were divided into blank control group, negative control group, aluminum exposure group, aluminum exposure+negative control group, aluminum exposure+miR-96-5p inhibition group, and miR-96-5p inhibition group. After transfecting PC12 cells with miR-96-5p inhibition and IRS1 siRNA for 24 h, the cells were divided into aluminum exposure+miR-96-5p inhibition+negative control group and aluminum exposure+miR-96-5p inhibition+IRS1 inhibition group. The control group was cultured in complete culture medium, and cells in the aluminum exposure group were treated with 200 μmol/L maltol aluminum for 24 hours. Cells in each group were collected and the apoptosis rate, miR-96-5p and IRS1 mRNA expression levels, as well as protein expression levels of Caspase3, Cleaved-caspase3, IRS1, p-AKT, and p-GSK3β were measured. Results: After 24 hours of exposure, compared with blank control group and low-dose group, the apoptosis rates, relative expressions of Caspase3 and Cleaved-caspase3 proteins, and relative expressions of miR-96-5p in the medium and high-dose groups of PC12 cells were significantly increased, while the relative expression levels of IRS1 mRNA, IRS1, p-AKT and p-GSK3β proteins were significantly decreased (P<0.05). Targetscan prediction and double luciferase report experiment both proved that IRS1 was a direct target gene of miR-96-5p. In the transfection experiment, compared with the aluminum exposure group, the apoptosis rate, the relative expressions of Caspase3 and Cleaved-caspase3 proteins, the relative expression of miR-96-5p in the aluminum exposure+miR-96-5p inhibition group were significantly decreased, while the relative expression levels of IRS1 mRNA and IRS1, p-AKT and p-GSK3β proteins were significantly increased (P<0.05). In the IRS1 low expression experiment, compared with the aluminum exposure+miR-96-5p inhibition+negative control group, the apoptosis rate, the relative expressions of Caspase3 and Cleaved-caspase3 proteins in the aluminum exposure+miR-96-5p inhibition+IRS1 inhibition group were significantly increased, while the relative expression levels of IRS1 mRNA and IRS1, p-AKT and p-GSK3β proteins were significantly decreased (P<0.05) . Conclusion: The increased expression of miR-96-5p and the targeted inhibition of IRS1 may be one of the mechanisms of apoptosis of PC12 cells induced by maltol aluminum exposure.

Arterial Spin Labeling-Based MRI Estimation of Penumbral Tissue in Acute Ischemic Stroke

BACKGROUND

Arterial spin labeling (ASL) has shown potential for the assessment of penumbral tissue in patients with acute ischemic stroke (AIS). The postlabeling delay (PLD) parameter is sensitive to arterial transit delays and influences cerebral blood flow measurements.

PURPOSE

To assess the impact of ASL acquisition at different PLDs for penumbral tissue quantification and to compare their performance regarding assisting patient selection for endovascular treatment with dynamic susceptibility contrast MRI (DSC-MRI) as the reference method.

STUDY TYPE

Retrospective.

POPULATION

A total of 53 patients (59.98 ± 12.60 years, 32% women) with AIS caused by internal carotid or middle cerebral artery occlusion.

FIELD STRENGTH/SEQUENCE

A 3-T, three-dimensional pseudo-continuous ASL with fast-spin echo readout.

ASSESSMENT

Hypoperfusion volume was measured using DSC-MRI and ASL with PLDs of 1.500 msec and 2.500 msec, respectively. Eligibility for endovascular treatment was retrospectively determined according to the imaging criteria of the Endovascular Therapy Following Imaging Evaluation for Ischemic Stroke trial (DEFUSE 3).

STATISTICAL TESTS

Kruskal-Wallis tests, Bland-Altman plots, Cohen's kappa, and receiver operating characteristic analyses were used. The threshold for statistical significance was set at P ˂ 0.05.

RESULTS

Hypoperfusion volume for ASL with a PLD of 1.500 msec was significantly larger than that for DSC-MRI, while the hypoperfusion volume for a PLD of 2.500 msec was not significantly different from that of DSC-MRI (P = 0.435). Bland-Altman plots showed that the mean volumetric error between the hypoperfusion volume measured by DSC-MRI and ASL with PLDs of 1.500/2.500 msec was -107.0 mL vs. 4.49 mL. Cohen's kappa was 0.679 vs. 0.773 for DSC-MRI and ASL, respectively, with a PLD of 1.500/2.500 msec. The sensitivity and specificity for ASL with a PLD of 1.500/2.500 msec in identifying patients eligible for treatment were 89.74% vs. 97.44% and 92.86% vs. 64.29%, respectively.

DATA CONCLUSION

In AIS, PLDs for ASL acquisition may have a considerable impact on the quantification of the hypoperfusion volume.

EVIDENCE LEVEL

3 TECHNICAL EFFICACY: Stage 2.

Small vessel disease burden predicts functional outcomes in patients with acute ischemic stroke using machine learning

AIMS

Our purpose is to assess the role of cerebral small vessel disease (SVD) in prediction models in patients with different subtypes of acute ischemic stroke (AIS).

METHODS

We enrolled 398 small-vessel occlusion (SVO) and 175 large artery atherosclerosis (LAA) AIS patients. Functional outcomes were assessed using the modified Rankin Scale (mRS) at 90 days. MRI was performed to assess white matter hyperintensity (WMH), perivascular space (PVS), lacune, and cerebral microbleed (CMB). Logistic regression (LR) and machine learning (ML) were used to develop predictive models to assess the influences of SVD on the prognosis.

RESULTS

In the feature evaluation of SVO-AIS for different outcomes, the modified total SVD score (Gain: 0.38, 0.28) has the maximum weight, and periventricular WMH (Gain: 0.07, 0.09) was more important than deep WMH (Gain: 0.01, 0.01) in prognosis. In SVO-AIS, SVD performed better than regular clinical data, which is the opposite of LAA-AIS. Among all models, eXtreme gradient boosting (XGBoost) method with optimal index (OI) has the best performance to predict excellent outcome in SVO-AIS. [0.91 (0.84-0.97)].

CONCLUSIONS

Our results revealed that different SVD markers had distinct prognostic weights in AIS patients, and SVD burden alone may accurately predict the SVO-AIS patients' prognosis.

Study on nitrogen demand model in pakchoi (Brassica campestris ssp. Chinensis L.) based on nitrogen contents and phenotypic characteristics

INTRODUCTION

In precision agriculture, the diagnosis of the nitrogen (N) nutrition status based on the plant phenotype, combined effects of soil types, various agricultural practices, and environmental factors which are essential for plant N accumulation. It helps to assess the N supply for plants at the right time and optimal amount to ensure high N use efficiency thereby reducing the N fertilizer applications to minimize environmental pollution. For this purpose, three different experiments were performed.

METHODS

A critical N content (Nc) model was constructed based on cumulative photothermal effect (LTF), Napplications, and cultivation systems on yield and N uptake in pakchoi.

RESULTS AND DISCUSSION

According to the model, aboveground dry biomass (DW) accumulation was found equal or below to 1.5 t/ha, and the Nc value was observed at a constant of 4.78%. However, when DW accumulation exceeded 1.5 t/ha, Nc declined with the increase in DW accumulation, and the relationship between Nc and DW accumulation developed with the function Nc %=4.78 x DW-0.33. An N demand model was established based on the multi-information fusion method, which integrated multiple factors, including Nc, phenotypical indexes, temperature during the growth period, photosynthetically active radiation, and N applications. Furthermore, the model's accuracy was verified, and the predicted N contents were found consistent with the measured values (R2 = 0.948 and RMSE = 1.96 mg/plant). At the same time, an N demand model based on N use efficiency was proposed.

CONCLUSIONS

This study can provide theoretical and technical support for precise N management in pakchoi production.

Physiological and Transcriptomic Analyses Uncover the Reason for the Inhibition of Photosynthesis by Phosphate Deficiency in Cucumis melo L

Phosphate (Pi) deficiency is a common phenomenon in agricultural production and limits plant growth. Recent work showed that long-term Pi deficiency caused the inhibition of photosynthesis and inefficient electron transport. However, the underlying mechanisms are still unknown. In this study, we used the physiological, histochemical, and transcriptomic methods to investigate the effect of low-Pi stress on photosynthetic gas exchange parameters, cell membrane lipid, chloroplast ultrastructure, and transcriptional regulation of key genes in melon seedlings. The results showed that Pi deficiency significantly downregulated the expression of aquaporin genes, induced an increase in ABA levels, and reduced the water content and free water content of melon leaves, which caused physiological drought in melon leaves. Therefore, gas exchange was disturbed. Pi deficiency also reduced the phospholipid contents in leaf cell membranes, caused the peroxidation of membrane lipids, and destroyed the ultrastructure of chloroplasts. The transcriptomic analysis showed that 822 differentially expressed genes (DEGs) were upregulated and 1254 downregulated by Pi deficiency in leaves. GO and KEGG enrichment analysis showed that DEGs significantly enriched in chloroplast thylakoid membrane composition (GO:0009535), photosynthesis-antenna proteins (map00196), and photosynthesis pathways (map00195) were downregulated by Pi deficiency. It indicated that Pi deficiency regulated photosynthesis-related genes at the transcriptional level, thereby affecting the histochemical properties and physiological functions, and consequently causing the reduced light assimilation ability and photosynthesis efficiency. It enriches the mechanism of photosynthesis inhibition by Pi deficiency.

CE-MRI based radiomics in predicting the efficacy of neoadjuvant chemotherapy in non-mass enhancement HER2-positive invasive breast cancer

Objectives:

To establish and validate a radiomics nomogram based on CE-MRI for predicting the efficacy of NAC in HER2-positive breast cancer with NME.

Methods:

A cohort comprising 117 HER2-positive breast cancer patients showing NME on CE-MRI between January 2016 and June 2019.Patients were classified as pCR according to surgical specimens and axillary lymph nodes without invasive tumour cells. Clinicopathological data were recorded, and images were assessed by two radiologists. A total of 1130 radiomics features were extracted from the primary tumour and six radiomics features were selected by the maximal relevance and minimal redundancy (mRMR) and least absolute shrinkage and selection operator (LASSO) algorithms. Univariate logistic regression was used to screen meaningful clinical and imaging features. The rad-score and independent risk factors were incorporated to build a nomogram model. Calibration and receiver operator characteristic curves (ROC) were used to confirm the performance of the nomogram in the training and validation cohorts. The clinical usefulness of the nomogram was evaluated by decision curve analysis (DCA).

Results:

The difference in the rad-score between the pCR and non-pCR groups was significant in the training and testing cohorts (p < 0.01). The nomogram model showed good calibration and discrimination, with AUCs of 0.900 and 0.810 in the training and testing cohorts. DCA indicated that the radiomics-based model was superior in terms of patient clinical benefit.

Conclusion:

The MRI-based radiomics nomogram model could be used to preoperatively predict the efficacy of NAC in HER2-positive breast cancer patients showing NME.

Advances in knowledge:

HER2 breast cancer showed segmental enhancement on CE-MRI and was more likely to achieve pCR after NAC than regional enhancement and diffuse enhancement. The MRI-based radiomics nomogram model could be used to preoperatively predict the efficacy of NAC in HER2-positive breast cancer that showed non-mass enhancement.

Monitoring mild cognitive impairment of workers exposed to occupational aluminium based on quantitative susceptibility mapping

AIM

To investigate the diagnostic value of quantitative susceptibility mapping (QSM) in mild cognitive impairment (MCI) of aluminium (Al) workers.

MATERIALS AND METHODS

The basic data of 53 workers in an Al factory were collected and divided into the MCI group and normal control (NC) group by Montreal Cognitive Assessment (MoCA) scores. All participants were tested for plasma Al concentration and had magnetic resonance imaging (MRI). The QSM values of many areas of the brain were delineated and measured. Independent two-sample t-tests or non-parametric tests were used to compare the parameter values between the two groups. Spearman's correlation analysis was performed between QSM values, MoCA scores, and plasma Al concentration. The receiver operating characteristic curve and z test were performed to assess diagnostic efficacy and the best parameter.

RESULTS

There was no difference in age and educational level. Plasma Al concentration of the MCI group was higher than that of NC group (p=0.057). QSM values of the left hippocampus, left dentate nucleus, right substantia nigra, and left putamen in MCI group were higher than that of NC group (p<0.05), and the left hippocampus had the best diagnostic efficacy. QSM values correlated negatively with MoCA scores. No correlation was found between QSM values and plasma Al concentration (p>0.05).

CONCLUSION

QSM might be a neuroimaging marker for the diagnosis of MCI. The left hippocampus showed the best diagnostic efficacy. Plasma Al concentration of the MCI group was higher than that of the NC group. A correlation between QSM and plasma Al concentration was not found.

Controllable synthesis and stabilization of Tamarix aphylla-mediated copper oxide nanoparticles for the management of Fusarium wilt on musk melon

Excessive use of pesticides and mineral fertilizers poses a serious threat to ecoenvironment sustainability and human health. Nano pesticides or Nano fungicides have attained great attention in the field of agriculture due to their unique characteristics, by improving crop growth with enhancing pathogenesis-related defense system. However, there is a need to develop a sustainable mechanism for the synthesis of fungicides which replace the chemical pesticides to avoid their hazardous impact. Here in, Tamarix aphylla mediated CuO-Nanoparticles (NPs) were synthesized, characterized and their activity was evaluated under in-vitro and in-vivo conditions. The structural and elemental analysis of NPs were carried out by using X-ray powder diffraction (XRD), Fourier transformed infrared spectroscopy (FTIR), UV-visible spectrophotometer, Scanning electron microscope (SEM) and Transmission electron microscope (TEM). In the greenhouse, at an optimum concentration of 50 mg/L reduced disease severity very effectively and enhanced plant growth. Application of NPs also assisted in the induction of systemic response of defense-related genes in melon. Under In vitro condition at 100 mg/L significantly reduced mycelial growth (84.5%) by directly acting on the pathogenic cell wall. Our work confirmed that dosedependent concentration of T. aphylla extract based biological CuO-NPs enhance plant growth and help to effectively resist against F. oxysporum infection.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13205-022-03189-0.

[The impact of occupational aluminum exposure on workers' overall cognitive function and various cognitive fields]

Objective: To evaluate the effects of occupational aluminum exposure on workers' overall cognitive function and cognitive fields. Methods: From July to August 2019, using the method of cluster sampling, 101 and 117 workers were selected from the electrolytic aluminum workshop of an aluminum plant in a region and the maintenance workshop of a plant in the same region. The venous blood of the subjects was collected, the plasma was extracted, and the blood aluminum concentration was measured by ICP-MS. According to the blood aluminum concentration and type of work, 93 workers who were lower than the median blood aluminum concentration and in the maintenance workshop of a factory were divided into low aluminum exposure group, and 85 workers who were higher than the median blood aluminum concentration and in the electrolytic aluminum workshop of an aluminum factory were divided into high aluminum exposure group. The basic information of the respondents, was collected through the employee physical examination form. The overall cognitive function of workers was evaluated by Beijing Montreal Cognitive Assessment Scale (MoCA) . Multiple linear regression analysis and logistic regression analysis were used for multiple statistical analysis. Results: Compared with the low aluminum exposure group (25.42±1.808) , the total score of MoCA in the high aluminum exposure group (23.84±2.919) was significantly lower, and the scores of visual space, executive function, abstract and delayed recall were significantly lower (P<0.05) . Linear regression analysis showed that the total score of MoCA, visual space and executive function, naming and delayed recall were negatively correlated with blood aluminum concentration (β=-0.018、-0.008、-0.003、-0.008, P<0.05) .MOCA total score, visual space and executive function, attention, language, abstraction, orientation were positively correlated with educational level (β=0.853、0.310、0.216、0.171、0.412、0.122, P<0.05) . Logistic regression analysis showed that adjusting for age, smoking, drinking and education, blood aluminum was a risk factor for mild cognitive impairment (OR=1.017, P<0.05) ; Education level was the protective factor of mild cognitive impairment (OR=0.419, P<0.05) . Conclusion: Occupational aluminum exposure can affect the overall cognitive function of workers, and occupational aluminum exposure increases the risk of MCI.

[Effects of occupational exposure to aluminum on verbal function of workers]

Objective: To explore the effect of occupational aluminum (Al) exposure on workers' overall cognitive level and speech function. Methods: In July 2019, by using cluster sampling method, the group of 232 exposed to Al from an Al plant in Shanxi Province were selected as the exposed group, and the group of 228 not exposed to Al were selected as the control group. The blood Al concentration was determined by inductively coupled plasma mass spectrometry (ICP-MAS) . The exposed group was divided into high exposure group and low exposure group according to the median (M) concentration of Al in serum. The general cognitive function and speech function were evaluated with the Montreal Cognitive Assessment Scale (MoCA) , and the differences in the general cognitive function and speech function between the groups were compared, and non-conditional logistic regression was used to analyze the possible influencing factors of mild cognitive impairment (MCI) . Results: There were significant differences in age, working age, education and drinking status between Al exposed group and control group (P<0.05) . The total MoCA score, animal naming tese (ANT) score and category fluency repetition (CFT) score in Al exposure group were lower than control group and the differences were statistically significant (P<0.05) . The full rate of ANT was lower than that of CFT in Al exposure group (P<0.05) . The total MoCA score, ANT score and CFT score in the high exposure group were significantly lower than those in the control group (P<0.05) . The score of MoCA, ANT and CFT in high exposure group were lower than those in low exposure group between the level of serum aluminum>60 μg/L group and ≤60 μg/L group (P<0.05) . Logistic regression analysis showed that working age, serun Al concentration, ANT score, CFT score and SR score were the possible influencing factors of MCI in occupational Al exposure workers (P<0.05) . Conclusion: Occupational Al exposure can lead to impaired speech function of workers, the higher the ANT score, CFT score and SR score, the lower working age and serum Al concentration, the lower risk of MCI.

Histogram analysis of quantitative parameters from synthetic MRI: Correlations with prognostic factors and molecular subtypes in invasive ductal breast cancer

PURPOSE

To evaluate intra-tumoral heterogeneity through a histogram analysis of quantitative parameters obtained from synthetic MRI (magnetic resonance imaging), and determine correlations of these histogram characteristics with prognostic factors and molecular subtypes of invasive ductal carcinoma (IDC).

METHODS

A total of 122 IDC from 122 women who underwent preoperative synthetic MRI and DCE (dynamic contrast enhancement)-MRI were investigated. The synthetic MRI parameters (T1, T2, and PD (proton density)) were obtained. For each parameter, the minimum, 10th percentile, mean, median, 90th percentile, maximum, skewness, and kurtosis values of tumor were calculated, and correlations with prognostic factors and subtypes were assessed. The Mann-Whitney U test or the Student^'s t test were utilized to analyze the association between the histogram features of synthetic MRI parameters and prognostic factors. The Kruskal-Wallis test followed by the post-hoc test was used to analyze differences of synthetic MRI parameters among molecular subtypes.

RESULTS

IDC with high histopathologic grade showed statistically higher PD_maxium, T1_mean and T1_median values than those with low grade (p = 0.003, p = 0.007, p = 0.003). The T1_10th were significantly higher in cancers with PR (progesterone receptor) negativity than those with PR positivity (p = 0.005). ER-negative cancers had significant higher values of T2_10th, T2_mean, and T2_median than ER-positive cancers (p = 0.006, 0.002, and 0.006, respectively). The values of PD_median were significantly higher in IDC with HER2 (human epidermal growth factor receptor 2) positivity than those with HER2 negativity (p = 0.001). When discriminating molecular subtypes of IDC, the T2_mean achieved the highest performance. The T2_mean values of TN (triple-negative), luminal B and luminal A types are arranged in descending order (p <  0.0001).

CONCLUSIONS

Histogram features derived from synthetic MRI quantifies the distributions of tissue relaxation time and proton density, and may serve as a potential biomarker for discriminating histopathological grade, hormone receptor status, HER2 expression status and breast cancer subtypes.

Plant buffering against the high-light stress-induced accumulation of CsGA2ox8 transcripts via alternative splicing to finely tune gibberellin levels and maintain hypocotyl elongation

In plants, alternative splicing (AS) is markedly induced in response to environmental stresses, but it is unclear why plants generate multiple transcripts under stress conditions. In this study, RNA-seq was performed to identify AS events in cucumber seedlings grown under different light intensities. We identified a novel transcript of the gibberellin (GA)-deactivating enzyme Gibberellin 2-beta-dioxygenase 8 (CsGA2ox8). Compared with canonical CsGA2ox8.1, the CsGA2ox8.2 isoform presented intron retention between the second and third exons. Functional analysis proved that the transcript of CsGA2ox8.1 but not CsGA2ox8.2 played a role in the deactivation of bioactive GAs. Moreover, expression analysis demonstrated that both transcripts were upregulated by increased light intensity, but the expression level of CsGA2ox8.1 increased slowly when the light intensity was >400 µmol·m^-2·s^-1 PPFD (photosynthetic photon flux density), while the CsGA2ox8.2 transcript levels increased rapidly when the light intensity was >200 µmol·m^-2·s^-1 PPFD. Our findings provide evidence that plants might finely tune their GA levels by buffering against the normal transcripts of CsGA2ox8 through AS.

Copy number variation in HOXB7 and HOXB8 involves in the formation of beard trait in chickens

The derived feathering phenotype beard in domestic birds is an ideal resource to investigate the genetic mechanisms controlling feather development and differentiation. In the present study, we performed a GWAS and QTL linkage analysis on the trait of beard in Beijing fatty chicken. One major QTL (1.2-1.9 Mb) was identified that could explain 34% of the phenotypic variation. The copy number variation that was copied from the region (GGA27:3 578 409-3 592 890 bp) containing homebox B7 (HOXB7) and homebox B8 (HOXB8) was validated to be only exhibited in the genome of bearded chickens. Protein-protein interaction analysis indicated that HOXB7 and HOXB8 proteins could highly interact with the HOXB family members, including HOXB4, HOXB5 and HOXB6, whose genomic locations near HOXB7 and HOXB8 suggested that they may regulate their family members to involve in the formation of the beard trait in chickens. Overall, our work provides basic data for understanding the mechanisms regulating beard development and differentiation.

Self-made Salmonella Pullorum agglutination antigen development and its potential practical application

Pullorum disease caused by Salmonella Pullorum is one of the most important infectious diseases in the poultry industry worldwide, which leads to serious economic losses in many developing countries because of its high mortality rate in young chicks. The traditional slide agglutination test with low cost, fast reaction, and on-site detection has been widely used in the diagnosis of Pullorum disease. However, in practice, the test performance is with the disadvantages of false positive results and unstable detection results. In this paper, we developed self-made agglutination antigens prepared by local isolates in the poultry farm and compare the detection performance with commercial agglutination antigens (China Institute of Veterinary Drug Control) and Group D Salmonella ELISA kit (BioChek UK Ltd). The results of detecting 200 serum samples indicated that the consistency of commercial agglutination antigen detecting in 2 times was only 79.5%. Using the ELISA kit as the reference method, the commercial agglutination antigen detecting results of the Kappa test were only moderately consistent (0.58 ∼ 0.59). Meanwhile, positive and total coincidence rates of the self-made agglutination antigen test with more reliable repeat could reach 97.4 and 88%, respectively, and the result of Kappa test was highly consistent (0.75). The Receiver Operating Characteristic curve analysis clarified that the area under the receiver-operating-characteristic curve values of self-made and commercial agglutination antigen tests could reach 0.861 and 0.804, respectively. These results were coincident when detecting known positive serum from the infected chickens. It's worth mentioning that the visible positive reaction of self-made agglutination antigen test appeared faster and stronger than commercial antigen test. In conclusion, self-made Salmonella Pullorum agglutination antigen developed in this study was much better than commercial agglutination antigen and is expected to be a valuable tool in the diagnosis of the epidemiology of Salmonella Pullorum.

Fermi-Surface Instability in the Heavy-Fermion Superconductor UTe_{2}

Transport measurements are presented up to fields of 29 T in the recently discovered heavy-fermion superconductor UTe_{2} with magnetic field H applied along the easy magnetization a axis of the body-centered orthorhombic structure. The thermoelectric power varies linearly with temperature above the superconducting transition, T_{SC}=1.5  K, indicating that superconductivity develops in a Fermi liquid regime. As a function of field the thermoelectric power shows successive anomalies which appear at critical values of the magnetic polarization. Remarkably, the lowest magnetic field instability for H∥a occurs for the same critical value of the magnetization (0.4  μ_{B}) than the first order metamagnetic transition at 35 T for field applied along the b axis. It can be clearly identified as a Lifshitz transition. The estimated number of charge carriers at low temperature reveals a metallic ground state distinct from LDA calculations indicating that strong electronic correlations are a major issue.

Long-term prognostic value of coronary computed tomography angiography for asymptomatic patients with CAD in type 2 diabetes mellitus

The present study was performed to investigate the prognostic value of coronary computed tomography angiography (CTA) results for asymptomatic patients with coronary artery disease (CAD) in type 2 diabetes mellitus (T2DM). A total of 164 asymptomatic patients with T2DM were enrolled at Weifang Traditional Chinese Hospital (Weifang, China). Coronary plaques and stenosis severity were evaluated after CTA. Structures >1 mm² adjacent to or within the coronary artery lumen that could be clearly separated from the vessel lumen, was scored as a coronary plaque. Stenosis of ≥50% was considered as being obstructive. CAD was defined as the presence of any coronary plaque or a coronary artery calcium (CAC) score of >0. A CAC score of 0 and no coronary plaques was considered to indicate the absence of CAD. A 5-year follow-up was performed to determine the impact of the CTA findings and various clinicopathological characteristics on the prognosis of all participants. The primary end-point was any cardiac event. Event-free survival curves were plotted using the Kaplan-Meier method and compared using the log-rank test. Based on the coronary CTA results, the patients were classified into 3 groups according to the extent of stenosis: Normal coronary arteries, obstructive CAD and non-obstructive CAD. Significant differences in 5-year event-free survival were identified among the groups with normal coronary arteries, non-obstructive CAD and obstructive CAD (P=0.026). Further analysis indicated that the event-free survival rate of patients with 1-vessel CAD was 94.11%, that of patients with 2-vessel CAD was 73.68% and that associated with 3-vessel CAD was 61.54%. Multivariate Cox regression analysis revealed that non-obstructive as well as obstructive CAD diagnosed by coronary CTA are prognostic indicators for asymptomatic T2DM patients [hazard ratio (HR)=11.132, 95% confidence interval (CI): 1.857-66.742, P=0.008; HR=7.792, 95% CI: 1.750-34.698, P=0.007, respectively]. In conclusion, the present study suggests that coronary CTA may predict the prognosis of asymptomatic patients with T2DM.

Occupational allergy: is there a role for nanoparticles?

All fields of industry are applying nanotechnologies for the development of advanced materials, there¬fore at present the number of workers exposed to nanosized materials are significantly increasing. Unfortunately, protective equipment for nanoparticles (NPs) is of uncertain efficacy so the risk of noxious effects, in particular allergic sensitization, on workers gives many concerns. At the same time, studies of allergic physiopathology demonstrated that the lack of prevention and treatment could result in invalidating dis¬eases that, in case of professional etiology, might imply removal from the job and compensation. Therefore, a deeper knowledge of the role of NPs in inducing allergic diseases is mandatory to implement the risk assessment and preventive measures for nanosafety in the workplace. The possibility that NPs favor, ex¬acerbate or directly induce allergy is being suggested by recent experimental investigations in cellular and animal models. Unfortunately, studies are heterogeneous and few data have received experimental confir¬mation, lacking reproducibility. What comes to attention is the uncertainty about the real plausibility of the observed experimental effects, as there are only a few reported cases of allergy onset or exacerbation for workers exposed to NPs. However, the potential for NPs to induce, favor or exacerbate allergies seems possible even though not completely demonstrated. This should be a greater incentive to carry out appro¬priate epidemiological studies that are lacking and really needed.

[The study of the effects of occupational aluminum exposure on TNFR1 expression and cognitive function]

Objective: To analyze the relationship between cognitive function and tumor necrosis factor receptor 1 (TNFR1) expression of occupational exposed workers to aluminum and provide the basis for the diagnosis of cognitive impairment. Methods: 140 cases Shanxi aluminum plant workers were collected in 2016 as the research object, including 70 potroom workers for exposure group, 70 non-electrolytic aluminum plant workers in the control group, respectively. Using mini mental status examination (MMSE), digit span test (DST), fuld object memory examination(FOME) and simple reaction time test(SRTT) evaluate the cognitive function of objects. Using graphite furnace atomic absorption method for the determination of plasma aluminum levels as an indicator of aluminum contact exposure of workers. Using RT-PCR method for detection of tumor necrosis factor receptor 1 (TNFR1) mRNA expression levels. And comparison group differences in cognitive and TNFR1 mRNA expression levels. Results: The plasma aluminum content of exposed group (77.12±27.18) μg/L higher than the control group (55.6±28.69)μg/L (P=0.000); Compared to control group, FOME and MMSE score was significantly increased in the exposed group (P=0.000, P=0.000), SRTT scores significantly higher in the exposed group (P=0.001), DST no significant difference in the control group (P=0.893). Compared to control group, The mRNA expression of TNFR1 was significantly higher in the exposed group(P=0.002); Compared to control group, The protein expression of TNFR1 was significantly higher in the exposed group (P=0.002). By correlation analysis in exposure group, plasma aluminum content was negatively correlated with MMSE and the DST (r=-0.284, r=-0.331, P<0.05) and positively correlated with the SRTT, TNFR1 (mRNA) and TNFR1(protein)(r=0.255, r=0.333, r=0.987, P<0.01), MMSE was negatively related to TNFR1 (mRNA) and TNFR1 (protein) (r=-0.268, r=-0.255, P<0.05); DST was negatively correlated with the SRTT and TNFR1 (protein)(r=-0.267, r=-0.330, P<0.05); SRTT was positively correlated with TNFR1 (protein)(r=0.243, P<0.05); TNFR1 (mRNA) was positively correlated with TNFR1 (protein)(r= 0.340, P<0.01). Conclusion: Cognitive function change of occupational exposed workers to aluminum was related to the increase of TNFR1 expression.

Physiological and Biochemical Responses of Cucumis melo L. Chloroplasts to Low-Phosphate Stress

Phosphorus (P) is a limiting plant soil nutrient. Long-term low inorganic phosphate (Pi) irreversibly damages plant cells and hinders plant growth. Plants have evolved several adaptive biochemical, physiological, and developmental responses to low-Pi stress. However, little is known about chloroplast responses to low-Pi stress. In this study, we used physiological and biochemical analyses to investigate melon chloroplast responses to low-Pi stress. The results indicated that low-Pi stress impeded melon seedling growth and reduced its dry matter content by inhibiting the photosynthesis. Low-Pi stress reduced the P content in shoots, which inhibited ATP synthase (ATP-ase) activity, and disturbed the proton and electron transport efficiency on chloroplast photosynthetic electron transport chain. In addition, low-Pi stress induced reactive oxygen species (ROS) production in the leaves, which caused membrane peroxidation. Therefore, redox homeostasis was not maintained, and the melon leaves presented with symptoms of photooxidative stress. To mitigate photoinhibition, the melon plants initiated non-photochemical chlorophyll fluorescence quenching (NPQ) initiated by acidification of the thylakoid lumen to dissipate excess excitation energy, significantly improved ROS-scavenging enzyme activity. Based on these experimental results, we concluded that low Pi inhibited photosystem activity and caused photooxidative stress and photoinhibition. To alleviate these negative effects, the plant activated its NPQ mechanism, alternative electron transport pathways, and antioxidant system to protect its chloroplasts.

Texture features and pharmacokinetic parameters in differentiating benign and malignant breast lesions by dynamic contrast enhanced magnetic resonance imaging

Dynamic contrast enhanced magnetic resonance imaging (DCE-MRI) has become a powerful tool for the diagnosis of breast cancer in the clinical setting due to its high sensitivity and specificity. Pharmacokinetic parameters, including Ktrans and area under the curve (AUC), and texture features derived from DCE-MRI have been used to specify the characteristics inside tumors. In the present study, 56 patients (average age 45.3±11.1; range 25-69 years) with histopathologically proved breast tumors were analyzed using the pharmacokinetic parameters and texture features. Malignant tumors displayed higher Ktrans and AUC values than the benign, Ktrans exhibited a significantly difference between the malignant and benign tumors (P=0.001) compared with the AUC values (P=0.029); texture features from DCE-MRI images and pharmacokinetic parameter maps also showed a good diagnostic ability. Alongside the routine method, principal components analysis (PCA) and Fisher discriminant analysis (FDA) were employed on these texture features to differentiate the breast lesions automatically. The Factor-1 scores of PCA were used to divide the patients into two groups, and the diagnosing accuracies of the FDA method on the texture features from DCE-MRI images, Ktrans maps, AUC maps were 93, 98 and 98%, with a cross validation accuracies of 82, 77 and 77%, respectively. To conclude, pharmacokinetic parameters, texture features and the combined computer-assisted classification method were discussed. All method involved in this study may be a potential assisted tool for radiological analysis on breast.

Maximizing T c by tuning nematicity and magnetism in FeSe1-x S x superconductors

A fundamental issue concerning iron-based superconductivity is the roles of electronic nematicity and magnetism in realising high transition temperature (T c). To address this issue, FeSe is a key material, as it exhibits a unique pressure phase diagram involving non-magnetic nematic and pressure-induced antiferromagnetic ordered phases. However, as these two phases in FeSe have considerable overlap, how each order affects superconductivity remains perplexing. Here we construct the three-dimensional electronic phase diagram, temperature (T) against pressure (P) and isovalent S-substitution (x), for FeSe1-x S x . By simultaneously tuning chemical and physical pressures, against which the chalcogen height shows a contrasting variation, we achieve a complete separation of nematic and antiferromagnetic phases. In between, an extended non-magnetic tetragonal phase emerges, where T c shows a striking enhancement. The completed phase diagram uncovers that high-T c superconductivity lies near both ends of the dome-shaped antiferromagnetic phase, whereas T c remains low near the nematic critical point.

Quasilinear quantum magnetoresistance in pressure-induced nonsymmorphic superconductor chromium arsenide

In conventional metals, modification of electron trajectories under magnetic field gives rise to a magnetoresistance that varies quadratically at low field, followed by a saturation at high field for closed orbits on the Fermi surface. Deviations from the conventional behaviour, for example, the observation of a linear magnetoresistance, or a non-saturating magnetoresistance, have been attributed to exotic electron scattering mechanisms. Recently, linear magnetoresistance has been observed in many Dirac materials, in which the electron–electron correlation is relatively weak. The strongly correlated helimagnet CrAs undergoes a quantum phase transition to a nonmagnetic superconductor under pressure. Here we observe, near the magnetic instability, a large and non-saturating quasilinear magnetoresistance from the upper critical field to 14 T at low temperatures. We show that the quasilinear magnetoresistance may arise from an intricate interplay between a nontrivial band crossing protected by nonsymmorphic crystal symmetry and strong magnetic fluctuations.

The electronic structure of the helimagnet CrAs is unusual due to its nonsymmorphic crystal symmetry. Here, the authors observe quasilinear magnetoresistance close to a pressure-driven superconducting transition, which may arise from the interaction of the band structure and magnetic fluctuations.

[The effect of aluminum trichloride on expression of phosphorylated tau and Aβ in SH-SY5Y cells]

Objective: To investigate the expression of phosphorylated tau (p-tau) and Aβ in SH-SY5Y cells induced by aluminum or/and ApoE ε4 allele, and study the interaction between aluminum and ApoE ε4 allele. Methods: SH-SY5Y cells were assigned to control group, 400 μmol/L AlCl(3) group, ApoEε4 transfected group and 400 μmol/L AlCl(3) with Apo Eε4 transfected group. The cell viability was measured by CCK-8 assay; the expressions of p-tau and Aβ was determined with ELISA Kit after AlCl(3) exposure or or/and ApoE ε4 transfection. Results: The viability of cells exposed to 400 μmol/L AlCl(3) or/and ApoE ε4 transfected were significantly lower than that of controls (P<0.05) . The expressions of total tau, tau-181, tau-231, tau-396 and Aβ in 400 μmol/L Al(3)+ or/and ApoE ε4 transfected exposed cells showed significantly higher than those of controls (P<0.05) . Based on the factorial design, a significant interaction exists, and there is a synergistic effect between AlCl(3) and ApoE ε4 (P<0.05) . Conclusion: Aluminum and ApoE ε4 allele could increase expression of p-tau and Aβ deposition; there was a synergistic interaction between aluminum and ApoE ε4 allele on cell death, tau phosphorylation and Aβ deposition of SH-SY5Y.

[Effects of subchronic aluminum exposure on long-term potentiation and activities of RAS and extracellular regulated protein kinases in rats]

Objective: To study the effects of subchronic aluminum exposure on LTP and activities of RAS and ERK in rats in vivo. Methods: 24 Wistar rats were randomly divided into control group、low-dose group、medium-dose group and high-dose group, and received saline (control group) or Al (mal) (3) (15 μmol、kg、30 μmol、kg or 45 μmol/kg) via intraperitoneal injection (i.p.) for 8 weeks, respectively. The fEPSP in CA1 region were recorded by field potentiation technique in vivo and the hippocampal activities of RAS and ERK were examined by ELISA. Results: The fEPSP amplitudes of the control group were 1.90±0.19, 1.64±0.15 and 1.54±0.08 at 1, 30 and 60 min after HFS, respectively. The fEPSP amplitudes of the low-dose group were 1.40±0.06 at 60 min, which represented a statistically significant decrease compared to the control group (P<0.05) ; these values at 30min and 60min dropped to 1.33±0.20 and 1.12±0.07 in the medium-dose group (P<0.05) and further decreased to 1.05±0.05 and 0.91±0.10 in the high-dose group (P<0.05) . And the activity dose-dependent decreases were observed both in RAS and ERK: compared with the control group and the low-dose group, the activities of RAS and ERK of the medium-dose and high-dose group significantly decreased (P<0.05) and compared with the medium-dose group, the activities of the high-dose group statistically dropped (P<0.05) . Conclusion: RAS and ERK may be related to the suppression of LTP by subchronic aluminum exposure and the RAS-MAPK transduction pathway may be involved in the damage of learning and memory induced by aluminum.

[Association between serum aluminium level and methylation of amyloid precursor protein gene in workers engaged in aluminium electrolysis]

OBJECTIVE

To investigate the association between serum aluminium level and methylation of the promoter region of amyloid precursor protein (APP)gene in workers engaged in aluminium electrolysis.

METHODS

In 2012, 366 electrolysis workers in an aluminium factory were enrolled as exposure group (working years >10 and age >40 years)and divided into low-exposure group and high-exposure group based on the median serum aluminium level. Meanwhile, 102 workers in a cement plant not exposed to aluminium were enrolled as control group. Graphite furnace atomic absorption spectrometry was used to measure serum aluminium level, methylation specific PCR was used to measure the methylation rate of the promoter region of APP gene, and ELI-SA was used to measure the protein expression of APP in lymphocytes in peripheral blood.

RESULTS

The exposure group had a significantly higher serum aluminium level than the control group (45.07 μg/L vs 30.51 μg/L, P< 0.01). The exposure group had a significantly lower methylation rate of the promoter region of APP gene than the control group (18.85% vs 25.49%, P=0.025), and the high-exposure group had a significantly lower methylation rate of the promoter region of APP gene than the low-exposure group (15.84% vs 21.85%, P<0.05). The exposure group had a significantly higher protein expression of APP in lymphocytes in peripheral blood than the control group (66.73 ng/ml vs 54.17 ng/ml, P<0.05); compared with the low-exposure group (65.39 ng/ml), the high-exposure group showed an increase in the protein expression of APP in lymphocytes in peripheral blood (67.22 ng/ml), but there was no significant difference between these two groups (P>0.05). The multivariate logistic regression analysis showed that with reference to the control group, low aluminium exposure (OR=1.86, 95% CI 1.67~3.52)and high aluminium exposure (OR=2.98, 95% CI 1.97~4.15)were risk factors for a reduced methylation rate of the promoter region of APP gene.

CONCLUSION

Reduced methylation of the promoter region of APP gene may be associated with increased serum aluminium level, and downregulated methylation of the promoter region of APP gene may accelerate APP gene transcription.

[Influence of aluminum chloride exposure on embryonic development of zebrafish and neurobehavior of juvenile fish]

Objective: To investigate the influence of aluminum chloride (AlCl(3)) solution on the embryon-ic development of zebrafish and neurobehavior of juvenile fish. Methods: The embryos of zebrafishat 6 hours after fertilization were exposed to AlCl(3) solution at a concentration of 0, 55.0, 60.5, 66.6, 73.5, 80.5, or 100.0 mg/L, and embryonic hatching rates at 48 and 72 hours after fertilization were calculated. The embryos of zebrafishat 6 hours after fertilization were exposed to AlCl(3) solution at a concentration of 0, 60.0, 72.0, 86.4, 103.7, or 124.4 mg/L, and the embryonic mortality rates at 12, 24, 48, 72, and 96 hours after fertilization were calculat-ed. The embryos of zebrafish at 6 hours after fertilization were exposed to AlCl(3) solution at a concentration of 0, 50, 100, 200, 400, or 800 μg/L, and the changes in the neurobehavior of juvenile fish were observed after hatching, including touch-escape reaction at 72 hours after fertilization and autonomic movement and panic es-cape reflex at 7 days after fertilization. Results: Compared with the 0 mg/L group, the≥66.6 mg/L group had a sig-nificant reduction in embryonic hatching rate at 48 and 72 hours after fertilization, and the ≥72.0 mg/L group had a significant increase in embryonic mortality rate at 96 hours after fertilization (P<0.05) . Compared with the 0 μg/L group, the≥100 μg/L group had a significant reduction in the number of times of touch-escape reaction (P<0.05) .Compared with the 0 and 50 μg/L groups, the 100-800 μg/L groups had significant reductions in total movement distance and average speed (P<0.05) . Compared with the dark period before illumination, all groups had a significant increase in movement speed during the light period of the panic escape reflex test (i.e., the third minute) (P<0.05) ; within 2 minutes after the light was turned off, there was no significant change in movement speed in the 0-200 μg/L groups (P>0.05) ; the 400 and 800 μg/L groups had a significant increase in movement speed (P<0.05) . Conclusion: AlCl(3) exposure may cause embryonic developmental disorder in zebrafish and ab-normal neurobehavior in juvenile fish.

[Influence of occupational aluminum exposure on cognitive function and glutamate receptor protein expression in workers]

Objective: To investigate the influence of occupational aluminum exposure on cognitive function and glutamate receptor protein expression in peripheral blood lymphocytes in workers and the possibility of glutamate receptor being used as a biomarker for cognitive impairment in aluminum workers. Methods: From October to December, 2014, cluster sampling was performed to select 121 workers in aluminum electrolysis workshop as exposure group and 231 workers in thermoelectric workshop and logistics department as control group. Mini-Mental State Examination, clock drawing test, digit span test (DST) , verbal fluency test (VFT) , and Fuld Object-Memory (FOM) Evaluation were used to analyze cognitive function. Graphite furnace atomic absorption spectrophotometry was used to measure plasma aluminum level as an exposure indicator. Enzyme-linked immunosorbent assay was used to measure the content of glutamate receptor proteins in peripheral blood lymphocytes, including the subunits of N-methyl-D-aspartate receptor NR1, NR2A, and NR2B and metabotropic glutamate receptor 1 (mGluR1) . The correlation between cognitive function indices and the content of glutamate receptor proteins was analyzed. Results: There was no significant difference in plasma aluminum level between the control group and the exposure group (132.52±80.40 μg/L vs 182.88±72.32 μg/L, P>0.05) . According to the plasma aluminum level, the study subjects were divided into control group and low-, medium-, and high-level plasma aluminum groups, and there were significant differences in plasma aluminum level between these groups (all P<0.01) . The high-level plasma aluminum group had a significantly lower memory ability score than the control group and the low- and medium-level plasma aluminum groups (all P<0.05) . The high-level plasma aluminum group had lower DST and digital span forward (DSF) scores than the control group and the low-and medium-level plasma aluminum groups. The low-, medium-, and high-level plasma aluminum groups had lower digital span backward (DSB) scores than the control group. The medium-and high-level plasma aluminum groups had lower VFT scores than the control group and the low-level plasma aluminum group. The high-level plasma aluminum group had significantly lower expression of NR1 and NR2A proteins than the control group and the low-and medium-level plasma aluminum groups, and the medium- and high-level plasma aluminum groups had significantly higher expression of mGluR1 protein than the control group and the low-level plasma aluminum group (all P<0.05) . The expression of NR1 and NR2A proteins was negatively correlated with plasma aluminum level (r=-0.475 and -0.692, both P<0.05) , andthe expression of mGluR1 protein was positively correlated with plasma aluminum level (r=0.756, P<0.05) . The expression of NR1 protein was positively correlated with DSF, DSB, DST, and VFT scores (r(s)=0.213, 0.249, 0.271, and 0.228, all P<0.05) , and the expression of NR2A protein was positively correlated with VFT score (r(s)=0.206, P<0.05) . Conclusion: Occupational aluminum exposure may affect workers' memory function, and the expression of NR1 and NR2A in peripheral blood lymphocytes is correlated with cognitive function indices and can be used as biomarkers for cognitive impairment in aluminum workers.

Beneficial effects of deep sea fish oil on diabetic mice neurological injury

Deep sea fish oil mainly includes polyunsaturated fatty acid, which is usually used as health products and applied for prevention of cardiovascular and cerebrovascular diseases. However, there are only a few studies investigating the diabetes induced nerve injury till now. We established the diabetic model by using the 8-week old inbred male mice, and assumed that fish oil had a certain therapeutic effect on related neurosensory impairment and oxidative stress. Mice were divided into group A (diabetic mice induced by streptozotocin (STZ) and treated with fish oil), group B (diabetic mice) and group C (normal mice, without STZ treatment). The memory and exploration ability were evaluated and oxidation status of brain tissue was detected. Results indicated that memory and exploration ability of fish oil group A was significantly improved compared to diabetic group B (P&lt;0.05), and equal to group C. The malondialdehyde (MDA) level of fish oil group A was decreased significantly and antioxidant level was increased significantly compared to diabetic group B (P&lt;0.05), and equal to group C. In conclusion, deep sea fish oil could be used as auxiliary health care products, which plays important role in preventing and treating implications of nerve lesion impairment induced by diabetes mellitus.

[Association between H3K4me3/BDNF and the cognitive function of workers occupationally exposed to aluminum]

Objective: To investigate the influence of occupational aluminum exposure on cognitive function and its relationship with tri-methyl histone H3 lysine residues 4 points (H3K4me3) and brain-derived neurotrophic factor (BDNF) levels. Methods: By cluster random sampling method, a total of 235 cases of male workers selected from a Shanxi aluminum factory were recruited in the study in September 2015. Used the occupational epidemiological investigation questionnaire, which included Mini-Mental State Examination (MMSE) , Clock Drawing Test (CDT) , Digit Span Test (DST, including forward test DSFT and backward test DSBT) , Fuild Object Memory Evaluation (FOME) and Verbal Fluency Test (VFT) , to collect workers' basic information and assess their cognitive function score. Detected the concentration of aluminum in plasma by graphite furnace atomic absorption spectrometry. Workers were divided into three groups by the 25 percentile and 75 percentile of the aluminum content, such as low, middle and high aluminum concentration groups. The concentrations of H3K4me3 in lymphocyte and BDNF in plasma were determined by enzyme-linked immunosorbent assay. Results: The levels of aluminum in plasma was 134.36 (100.14, 178.96) μg/L. The scores of MMSE, DSFT, DSBT, DST of high aluminum concentration group were lower than low aluminum group (27.98±1.25 vs 28.83±1.54, 9.19±2.00 vs 10.64±2.87, 6.08±1.63 vs 7.19±3.07, 15.27±3.11 vs 17.81±4.72, all P<0.05) , the scores of CDT, FOME, VFT among three groups had no statistical significance (all P>0.05) . The expression levels of H3K4me3 and BDNF of high aluminum concentration group were lower than the low group [ (18.45±9.81) ng/μg Pro vs (23.76±9.89) ng/μg Pro, (26.07±10.18) ng/ml vs (31.66±9.24) ng/ml, all P<0.05]. Multiple correlation analysis showed that aluminum concentration were negatively correlated toH3K4me3, BDNF, MMSE, DSFT, DST, respectively (r(s)=-0.307、-0.214、-0.252、-0.197, -0.181, all P<0.01) . Conclusion: Exposure to occupational aluminum for a long time may change cognitive function, which go along with the decreasing of H3K4me3 level in lymphocyte and BDNF protein expression in plasma.

[Epidemiological characteristics of dyslipidemia in remote rural areas of Xinjiang, 2009-2010]

Objective: This study aimed to estimate the prevalence of dyslipidemia, hypertriglyceridemia, hypercholesterolemia, high blood low density lipoprotein cholesterol (LDL-C), and low blood high density lipoprotein cholesterol (HDL-C) in remote rural areas of Xinjiang and analyze these indicators' epidemiological characteristics. Methods: A survey of 13 000 individuals (aged ≥18 years) was conducted using a four-stage cluster random sampling method in Jiashi, Xinyuan, Aheqi, and Shawan Counties, Xinjiang, in 2009-2010. After nonpermanent residents were excluded, 12 154 individuals were included in this study. Questionnaire and physical examinations were conducted, including collection of fasting blood to detect TG, TC, LDL-C, and HDL-C. The results were calculated after complex weighting and compared according to the prevalence of different gender and age groups. Results: The overall levels of TG, TC, LDL-C, and HDL-C were 1.34±1.09, 4.45±1.16, 2.36±0.86, and 1.37±0.58 mmol/L, respectively. After complex weighting, the overall prevalence of dyslipidemia was 35.4%; that among men (42.9%) was greater than that among women (29.5%; χ²=234.19, P<0.001), and the prevalence was 35.9%, 34.5%, and 35.1% (χ²=1.52, P=0.467) in participants aged 18-44, 45-59, and ≥60 years, respectively. The overall prevalence of hypertriglyceridemia was 11.4%; that among men (13.5%) was greater than that among women (9.8%; χ²= 40.72, P<0.001), and the prevalence was 9.6%, 13.0%, and 13.2% (χ²=38.71, P<0.001) in participants aged 18-44, 45-59, and ≥60 years, respectively. The prevalence of hypercholesterolemia was 5.7%; that among men(5.0%) was greater than that among women (6.2%; χ²=6.95, P=0.008), and the prevalence was 3.5%, 7.4%, and 8.4% (χ²=105.24, P<0.001) in participants aged 18-4, 45-59, and ≥60 years, respectively. The prevalence of high blood LDL-C was 2.8%, and there was no significant difference between men (3.0%) and women (2.4%; χ²=1.43, P=0.231); the prevalence was 3.5%, 7.4%, and 8.4% (χ²=42.81, P<0.001) in participants aged 18-44, 45-59, and ≥60 years, respectively. The prevalence of low blood HDL-C was 24.0%; that among men (31.6%) was greater than that among women (18.0%; χ²=304.02, P<0.001), and the prevalence was 27.8%, 20.6% and 19.5% (χ²=96.61, P<0.001) in participants aged 18-44, 45-59, and ≥ 60 years, respectively. Conclusions: Low blood HDL-C was the main type of dyslipidemia among the population in remote rural areas of Xinjiang. The prevalence of dyslipidemia among men was greater than that among women, and there was a trend of younger men than women showing dyslipidemia.

[Association between CETP polymorphisms and haplotypes with dyslipidemia in Xinjiang Uygur and Kazak residents]

OBJECTIVE

To explore the relationship between the polymorphisms and haplotypes in the CETP gene and dyslipidemia among Xinjiang Kazak and Uygur residents.

METHODS

A population status survey was performed from 2010 to 2011 in Kashgar Xinjiang Uygur and Kazak residents, stratified cluster sampling method was used to select Uygur, Kazak residents with abnormal blood lipid values (n=367 and 345, respectively) as the dyslipidemia groups, and to select residents with normal lipid values as control group from the same area (n=374 and 390, respectively). SNaPshot technology was applied to detect the DNA of CETP gene rs3764261, rs1800775, rs708272 and rs5882 loci in all selected residents, and linkage disequilibrium analysis and haplotype construction were performed.

RESULTS

(1) In Uygur residents, the dyslipidemia risk of rs708272 CT (OR=0.64, 95%CI 0.46-0.91, P=0.01) and TT genotype (OR=0.60, 95%CI 0.40-0.91, P=0.02) was significantly lower than CC genotype. Dyslipidemia risk of rs3764261 GT (OR=0.55, 95%CI 0.40-0.74, P=0.00) and TT genotype (OR=0.47, 95%CI 0.28-0.78, P<0.01) was significantly lower than GG genetype. Dyslipidemia risk of the rs1800775 CC genotype was higher than AA genotype (OR=1.79, 95%CI 1.17-2.74, P=0.01). There was no statistical significance in CETP gene of the 4 genotype and allele frequency between the dyslipidemia and normal lipid groups in Kazak residents (all P>0.05). (2) In Uighur residents with dyslipidemia, HDL-C level was significantly higher in rs708272 TT genotype carriers than in CC and CT genotypes (all P<0.05) and in rs3764261 TT genotype carriers than in GG genotype carriers (P=0.008), while was significantly lower in rs1800775 CC genotype carriers with AA genotype carriers (P=0.008). (3) Linkage disequilibrium analysis showed that there was strong linkage disequilibrium between rs3764261 and rs708272 (D'=0.869, r(2)=0.869), rs1800775 and rs708272 (D'=0.845, r(2)=0.446) in Uighur residents, and there was strong linkage disequilibrium between rs3764261 and rs708272 (D'=0.963, r(2)=0.963), rs1800775 and rs708272 (D'=0.988, r(2)=0.630) in Kazak residents. (4) Significant differences were observed in frequency distribution of haplotype GACA(OR=0.579, 95%CI 0.388-0.864, P=0.006), GATA (OR=2.183, 95%CI 1.231-3.873, P=0.006), GCCA (OR=0.723, 95%CI 0.549-0.954, P=0.001), TATA (OR=0.723, 95%CI 0.549-0.954, P=0.021) and TATG (OR=0.601, 95%CI 0.429-0.841, P=0.002) in Uighur residents with normal or abnormal lipid profiles, while significant difference was observed in frequency distribution of haplotype GCCG (OR=1.961, 95%CI 1.207-3.188, P=0.005) in Kazak residents with normal or abnormal lipid profiles.

CONCLUSION

CETP genotype rs708272, rs3764261 and rs1800775 polymorphism is closely related to dyslipidemia and haplotype GACA, TATA and TATG will reduce the risk of dyslipidemia, while haplotype GATA, GCCA will increase the risk of dyslipidemia in Uygur residents. The four CETP polymorphisms are not related to the risk of dyslipidemia, but haplotype GCCG is related to increased risk of dyslipidemia in Kazakhs residents.

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.