Accurate detection of influenza A virus by use of a novel cross-priming isothermal amplification-based point-of-care assay.

Influenza virus is known to cause respiratory tract infections of varying severity in individuals of all ages. The EasyNAT Rapid Flu assay is a newly developed in vitro diagnostic test that employs cross-priming isothermal amplification (CPA) to detect and differentiate influenza A and B viruses in human nasopharyngeal (NP) swabs. The aim of this study is to determine the performance characteristics of the EasyNAT Rapid Flu assay for rapid detection of influenza virus. The limit of detection (LOD) and cross-reactivity of the EasyNAT Rapid Flu assay were assessed. The clinical performance of the assay was evaluated using NP swab samples that were tested with real-time reverse-transcription polymerase chain reaction (RT-PCR) and Xpert Xpress Flu/RSV assay. The LOD for the detection of influenza A and B using the EasyNAT Rapid Flu assay was found to be 500 copies/mL. Furthermore, the assay exhibited no cross-reactivity with other common respiratory viruses tested. For the 114 NP swab samples tested for influenza A using both the EasyNAT Rapid Flu assay and real-time RT-PCR, the two assays demonstrated a high level of agreement (κ = 0.963, P < 0.001), with a positive percentage agreement (PPA) of 97.7% and a negative percentage agreement (NPA) of 98.6%. Similarly, for the 43 NP swab samples tested for influenza A and B using both the EasyNAT Rapid Flu assay and Xpert Xpress Flu/RSV assay, the two assays showed a high level of agreement (κ = 0.933, P < 0.001), with the overall rate of agreement (ORA) of 97.7% for influenza A and 100% for influenza B. The EasyNAT Rapid Flu assay demonstrates excellent performance in the detection of influenza A, highlighted by its strong agreement with RT-PCR-based assays.IMPORTANCEThe newly developed EasyNAT Rapid Flu assay is an innovative cross-priming isothermal amplification-based method designed for detecting influenza A and B viruses at point-of-care settings. This study aims to thoroughly assess the analytical and clinical performance of the assay, offering valuable insights into its potential advantages and limitations. The findings of this research hold significant implications for clinical practice.

Peripheral blood lymphocyte subsets predict the efficacy of TACE with or without PD-1 inhibitors in patients with hepatocellular carcinoma: a prospective clinical study.

Background: Although peripheral blood lymphocyte subsets, particularly PD-1+ T cells, are promising prognostic indicators for patients with cancer. However, their clinical significance remains unclear. Methods: We prospectively enrolled 157 patients with hepatocellular carcinoma (HCC) treated with transcatheter arterial chemoembolization combined with or without PD-1 inhibitors. Twenty peripheral lymphocyte subsets and cytokines were analyzed. We analyzed the differences in PD-1+ T cells between patients treated with and without PD-1 inhibitors and their associations with tumor response, survival prognosis, and clinical features. Results: We found that the baseline CD8+PD-1+ and CD4+PD-1+ T-cell frequencies in patients who had received PD-1 inhibitors were lower than those in patients who had not received PD-1 inhibitors (p < 0.001). In the former patients, there were no differences in PD-1+ T-cell frequencies between the responder and non-responder subgroups (p > 0.05), whereas in the latter patients, the levels of CD8+PD-1+ T cells, CD4+PD-1+ T cells, and CD8+PD-1+/CD4+PD-1+ ratio did not predict tumor response, progression-free survival (PFS), or overall survival (OS) (p>0.05). Furthermore, in multivariate analysis of patients treated with or without PD-1 inhibitors revealed that the levels of CD8+CD38+ T cells (OR = 2.806, p = 0.006) were associated with tumor response, whereas those of CD8+CD28+ T cells (p = 0.038, p = 0.001) and natural killer (NK) cells (p = 0.001, p = 0.027) were associated with PFS and OS. Although, these independent prognostic factors were associated with progressive tumor characteristics (p<0.05), with the exception of CD8+CD28+ T cells, changes in these factors before and after treatment were unassociated with tumor response (p > 0.05). Conclusion: Circulating CD8+CD38+ T cells, CD8+CD28+ T cells, and NK cells were identified as potential prognostic factors for tumor response and survival in patients with HCC. Contrastingly, although PD-1 inhibitors can effectively block the T cell PD-1 receptor, the baseline PD-1+ T-cell frequencies and changes in the frequency of these cells have limited prognostic value.

Application of the Fluorescence Method on Sysmex XN9000 Hematology Analyzer for Correcting Platelet Count in Individuals with Microcytosis.

OBJECTIVE: Although small red blood cells are a well-known analytical pitfall that could cause artifactual increase of the platelet count, limited information is available on the accuracy of impedance platelet counting in cases with microcytosis. The aim of this study is to assess the accuracy of impedance platelet counting in the presence of small red blood cells, and to establish the optimal mean corpuscular volume (MCV) cutoff to endorse fluorescence platelet counting. METHODS: In this study, platelet counts estimated by the impedance method on the Sysmex XN9000 analyzer (Sysmex, Kobe, Japan) were compared with those provided by the fluorescence method. The accuracy of impedance platelet counting was assessed. Receiver operating characteristic curve was used to evaluate the performance of MCV in predicting falsely increased platelet counts. RESULTS: There was a tendency for the impedance method to overestimate the platelet count in samples with 70 fL < MCV ≤ 80 fL, 60 fL < MCV ≤ 70 fL, MCV ≤ 60 fL. Receiver operating characteristic curve analysis showed that a 73.5fL cutoff of MCV was highly sensitive in predicting falsely increased platelet counts. CONCLUSION: In cases with MCV < 73.5 fL, we strongly suggest that the platelet counts obtained by the impedance method on the Sysmex XN9000 analyzer should be checked and corrected by fluorescence counting.

Diagnosis of Acute Leukemia by Multiparameter Flow Cytometry with the Assistance of Artificial Intelligence.

We developed an artificial intelligence (AI) model that evaluates the feasibility of AI-assisted multiparameter flow cytometry (MFC) diagnosis of acute leukemia. Two hundred acute leukemia patients and 94 patients with cytopenia(s) or hematocytosis were selected to study the AI application in MFC diagnosis of acute leukemia. The kappa test analyzed the consistency of the diagnostic results and the immunophenotype of acute leukemia. Bland-Altman and Pearson analyses evaluated the consistency and correlation of the abnormal cell proportion between the AI and manual methods. The AI analysis time for each case (83.72 ± 23.90 s, mean ± SD) was significantly shorter than the average time for manual analysis (15.64 ± 7.16 min, mean ± SD). The total consistency of diagnostic results was 0.976 (kappa (κ) = 0.963). The Bland-Altman evaluation of the abnormal cell proportion between the AI analysis and manual analysis showed that the bias ± SD was 0.752 ± 6.646, and the 95% limit of agreement was from -12.775 to 13.779 (p = 0.1225). The total consistency of the AI immunophenotypic diagnosis and the manual results was 0.889 (kappa, 0.775). The consistency and speedup of the AI-assisted workflow indicate its promising clinical application.

Sialic Acid as a Suitable Marker of Clinical Disease Activity in Patients with Crohn's Disease.

OBJECTIVE: Elevated serum levels of sialic acid (SA) have been verified in patients with various inflammatory conditions. The association between the Crohn's disease (CD) activity and serum SA has been insufficiently studied. MATERIALS AND METHODS: Serum SA concentrations were determined using an enzymatic colorimetric assay method, and the correlation of SA with the Harvey-Bradshaw Index (HBI) and other inflammation activity markers was evaluated using the Spearman correlation. The predictive value of SA in estimating CD disease activity was assessed using the receiver operating characteristic. RESULTS: The SA levels were positively correlated with HBI and C-reactive protein (CRP) levels. The correlation of SA with the HBI was superior to that of CRP with the HBI. The area under the curve for SA was higher than that for CRP, with an optimal cutoff value of 53.14 mg/dL for active CD. CONCLUSION: Serum SA correlates with the HBI score better and has better predictive value in monitoring CD disease activity than CRP or other inflammatory markers.

Dendrimer-modified gold nanorods as a platform for combinational gene therapy and photothermal therapy of tumors.

BACKGROUND: The exploitation of novel nanomaterials combining diagnostic and therapeutic functionalities within one single nanoplatform is challenging for tumor theranostics. METHODS: We synthesized dendrimer-modified gold nanorods for combinational gene therapy and photothermal therapy (PTT) of colon cancer. Poly(amidoamine) dendrimers (PAMAM, G3) grafted gold nanorods were modified with GX1 peptide (a cyclic 7-mer peptide, CGNSNPKSC). The obtained Au NR@PAMAM-GX1 are proposed as a gene delivery vector to gene (FAM172A, regulates the proliferation and apoptosis of colon cancer cells) for the combination of photothermal therapy (PTT) and gene therapy of Colon cancer cells (HCT-8 cells). In addition, the CT imaging function of Au NR can provide imaging evidence for the diagnosis of colon cancer. RESULTS: The results display that Au NR@PAMAM-GX1 can specifically deliver FAM172A to cancer cells with excellent transfection efficiency. The HCT-8 cells treated with the Au NR@PAMAM-GX1/FAM172A under laser irradiation have a viability of 20.45%, which is much lower than the survival rate of other single-mode PTT treatment or single-mode gene therapy. Furthermore, animal experiment results confirm that Au NR@PAMAM-GX1/FAM172A complexes can achieve tumor thermal imaging, targeted CT imaging, PTT and gene therapy after tail vein injection. CONCLUSION: Our findings demonstrate that the synthesized Au NR@PAMAM-GX1 offer a facile platform to exert antitumor and improve the diagnostic level of tumor.

Identify Inflammatory Bowel Disease-Related Genes Based on Machine Learning.

The patients of Inflammatory bowel disease (IBD) are increasing worldwide. IBD has the characteristics of recurring and difficult to cure, and it is also one of the high-risk factors for colorectal cancer (CRC). The occurrence of IBD is closely related to genetic factors, which prompted us to identify IBD-related genes. Based on the hypothesis that similar diseases are related to similar genes, we purposed a SVM-based method to identify IBD-related genes by disease similarities and gene interactions. One hundred thirty-five diseases which have similarities with IBD and their related genes were obtained. These genes are considered as the candidates of IBD-related genes. We extracted features of each gene and implemented SVM to identify the probability that it is related to IBD. Ten-cross validation was applied to verify the effectiveness of our method. The AUC is 0.93 and AUPR is 0.97, which are the best among four methods. We prioritized the candidate genes and did case studies on top five genes.

Mindray SF-Cube technology: An effective way for correcting platelet count in individuals with EDTA dependent pseudo thrombocytopenia.

Several strategies are applied to determine the precise platelet count in individuals with ethylenediaminetetraacetic acid dependent pseudo thrombocytopenia (EDTA-PTCP) caused by in vitro aggregation of platelets in daily laboratory practice. None of them proves optimal for routine purposes. Thus, Mindray has developed the SF-Cube technology coupled with the CDR mode in the Mindray hematology analyzer to overcome the problem of EDTA-PTCP. With Mindray SF-Cube technology, platelet aggregates dissociate effectively and platelets are correctly counted in the CDR mode without pre-analytical management. In our studies, the EDTA-PTCP blood samples when analyzed with the CDR mode of Mindray BC-6800 plus analyzer, yield a markedly higher platelet count compared to those obtained with PLT-I on Sysmex XN-9000 hematology analyzer. We conclude that in patients with known or suspected EDTA-PTCP Mindray SF-Cube technology is a straightforward and effective way of determining the platelet count in EDTA-anticoagulated blood.

Predictive value of excision repair cross- complementation group 1 expression in locoregionally advanced nasopharyngeal carcinoma receiving cisplatin-based concurrent chemoradiotherapy.

BACKGROUND: Cisplatin-based concurrent chemoradiotherapy is recommended for nasopharyngeal carcinoma (NPC) at advanced stages. Excision repair cross-complementation group 1 (ERCC1) plays an important function in the repair of DNA damage that is a critical process of chemo- and radiotherapy. OBJECTIVE: This study aimed to investigate the clinical significance of ERCC1 expression in NPC treated with cisplatin-based concurrent chemoradiotherapy in locoregionally advanced NPC. METHODS: The expression level of ERCC1 and its association with clinicopathological characteristics in 205 locoregionally advanced NPC patients receiving cisplatin-based concurrent chemoradiotherapy were analyzed retrospectively. RESULTS: The correlation analysis revealed that the treatment-sensitive patients displayed dramatically lower ERCC1 expression than treatment-resistant cases did. Furthermore, the Kaplan-Meier plots revealed lower ERCC1 expression was significantly associated with better survival. Multivariate analysis further showed that the ERCC1 expression was an independent predictor of NPC patients' survival. CONCLUSIONS: ERCC1 expression might be a useful predictive marker in patients with locoregionally advanced NPC receiving cisplatin-based concurrent chemoradiotherapy.

Cytomegalovirus disease in nonimmunocompromised, human immunodeficiency virus-negative adults with chronic kidney disease.

BACKGROUND/PURPOSE(S): To identify the clinical characteristics of cytomegalovirus (CMV) disease in chronic kidney disease (CKD) patients. METHODS: Patients from two sources were reviewed: (1) a retrospective study of hospitalized patients admitted between January 1990 and February 2009 was performed at a tertiary hospital in Taiwan; (2) the English literature from 1990 to 2009 was reviewed for additional cases, and adults with CKD and histopathologically documented cytomegalovirus disease were included. RESULTS: Seven CKD patients from our hospital and seven from the literature were included. Nine (64.3%) patients were males, and the mean age was 66 years. Histopathologically proven CMV disease was present in the gastrointestinal (GI) tract of 13 (92.9%) and in the skin of one (7.1%) patient. GI symptoms included bleeding (78.6%), abdominal pain (35.7%), and diarrhea (28.6%).The most common comorbidities were diabetes mellitus (7, 50%) and hypertension (8, 57.1%). Thirteen patients had CMV GI disease. The endoscopic gross features of the GI tract lesions included single or multiple ulcers and a large polypoid or uneven surface mass. Of the seven cases with available data, a low body mass index (22.3 ± 1.3 kg/m(2)) and hypoalbuminemia (25 ± 7.0 g/L) were noted. Twelve patients had received ganciclovir or valganciclovir therapy. Five (35.7%) patients died, and the death of two patients was directly related to bowel perforation caused by CMV colitis. CONCLUSION: CMV disease may occur in CKD patients without the presence of overt immunodeficiency. The gastrointestinal tract is the most common site of involvement. Clinicians should be aware of this possibility in CKD patients who have GI symptoms.

Effect of acetazolamide and gingko biloba on the human pulmonary vascular response to an acute altitude ascent.

Acetazolamide and gingko biloba are the two most investigated drugs for the prevention of acute mountain sickness (AMS). Evidence suggests that they may also reduce pulmonary artery systolic pressure (PASP). To investigate whether these two drugs for AMS prevention also reduce PASP with rapid airlift ascent to high altitude, a randomized controlled trial was conducted on 28 healthy young men with acetazolamide (125 mg bid), gingko biloba (120 mg bid), or placebo for 3 days prior to airlift ascent (397 m) and for the first 3 days at high altitude (3658 m). PASP, AMS, arterial oxygen saturation (Sao2), mean arterial pressure (MAP), heart rate (HR), forced vital capacity (FVC), forced expiratory volume in the first second (FEV1), and peak expiratory flow (PEF) were assessed both at 397 m and 3658 m. HR, PEF, and PASP increased with altitude exposure (p<0.05), and SaO2 decreased (p<0.05). PASP with acetazolamide (mean at 3658 m, 26.2 mm Hg; incremental change, 4.7 mm Hg, 95% CI., 2.6-6.9 mm Hg) was lower than that with ginkgo biloba (mean at 3658 m, 33.7 mm Hg, p=0.001; incremental change, 13.1 mm Hg, 95%CI., 9.6-16.5 mm Hg, p=0.002), and with placebo (mean at 3658 m, 34.7 mm Hg, p<0.001; 14.4 mm Hg, 95% CI., 8.8-20.0 mm Hg, p=0.001). The data show that a low prophylactic dosage of acetazolamide, but not gingko biloba, mitigates the early increase of PASP in a quick ascent profile.

Akt activation protects liver cells from apoptosis in rats during acute cold exposure.

Accidental deaths due to exposure to extremely low natural temperature happen every winter. Exposure to extreme cold causes injury of multiple organs. However, early responses of the bodies to acute extreme cold exposure remain incompletely understood. In this study, we found that hepatic glycogen was rapidly reduced in rats exposed to -15°C, and the key enzymes required for glycogenesis were upregulated in the livers of the cold-exposed rats. In line with the rapid consumption of glycogen, acute cold exposure induced a transient elevation of cellular ATP level, which lasted about one hour. The ATP level went back to basal level after two hours of cold exposure. Four hours of cold exposure resulted in cellular ATP depletion and cell apoptosis. The dynamic change of cellular ATP levels was well associated with Akt activation in cold-exposed liver cells. The activation of Akt was required for cold exposure-induced ATP elevation. Blockade of Akt activation diminished the transient increase of intracellular ATP content and exacerbated cell apoptosis during acute cold exposure. These results suggest that Akt activation plays a pivotal role in maintaining cellular bioenergy balance and promoting liver cell survival during acute cold exposure.

The role of autophagy dysregulation in manganese-induced dopaminergic neurodegeneration.

The etiological role of dysregulated autophagy in neurodegenerative diseases has been a subject of intense investigation. While manganese (Mn) is known to cause dopaminergic (DAergic) neurodegeneration, it has yet to be determined whether the dysregulation of autophagy plays a role in Mn-induced neuronal injury. In this study, we investigated the effect of Mn on autophagy in a rat model of manganism, a neurodegenerative disease associated with excessive exposure to Mn. After a single intrastriatal injection of Mn, the short- (4-12 h) and long-term (1-28 days) effect of Mn on DAergic neurons and autophagy were examined. Marked reduction in the number of TH-immunoreactive neurons in the substantia nigra pars compacta (SNpc) as well as TH protein expression, and a significant increase of apomorphine-induced rotations were observed in rats after Mn injection. Manganese also induced the down-regulation of dopamine levels and D1 dopamine receptor expression. In addition, autophagy was dysregulated and inhibited, as evidenced by increased number of abnormal lysosomes, decreased protein expression of Beclin1, and decreased ratio of microtubule-associated protein 1 light chain 3 (LC3) II over LC3 I, concomitant with activated mammalian target of rapamycin (mTOR)/p70 ribosomal protein S6 kinase (p70s6k) signaling. In contrast, in the early phase of Mn exposure, the level of autophagy was not be suppressed but compensatorily activated. Although the morphology of the DAergic neuron was intact in the early phase, Mn caused a significant decrease in TH-immunoreactivity and a significant increase in apomorphine-induced rotations in the presence of wortmannin, an inhibitor of autophagy. Taken together, these results demonstrate, for the first time, that autophagy may play a protective role against Mn-induced neuronal damage, whilst dysregulation of autophagy at later phases may mediate DAergic neurodegeneration.

The effect of sodium selenite on lead induced cognitive dysfunction.

The effect of lead (Pb) on spatial memory and hippocampal long-term potentiation (LTP) as a key risk factor has been widely recognized and the oxidative damage has been proposed as a possible mechanism of lead neurotoxicity. Selenium (Se) is a nutritionally essential trace element with known antioxidant potential. In this study we investigated the effect and the underlying mechanisms of Se supplementary on Pb induced cognition and synaptic plasticity impairment. Lactating Sprague-Dawley rats (SD rats) were randomly divided to four groups: 0ppm lead acetate (Pb); 0ppm Pb and 0.2ppm sodium selenite (Se); 100ppm Pb; 100ppm Pb and 0.2ppm Se. Lactating rats were treated with or without Pb and/or Se throughout lactation until weaning. The levels of hippocampal LTP, the spatial memory, the apoptosis of hippocampal neurons, the levels of lactate dehydrogenase (LDH) release, and the serum level of superoxide dismutase (SOD) and malondialdehyde (MDA) were assayed. It had been observed that in Pb group the spatial memory, the induce level of LTP, the serum SOD level decreased, the LDH release level, the neurons apoptosis level, the serum MDA level increased, while in the Se supplements groups, the spatial memory, the induce level of LTP increased significantly. Compared with the Pb group, Se supplements shown down regulated the level of LDH, the neurons apoptosis and the serum MDA, and up regulated the level of serum SOD. We could draw the conclusion that Se supplements could alleviate toxic effect of lead on hippocampal LTP and spatial memory. The treated with selenium around 0.2ppm may protect against spatial memory dysfunction induced by lead exposure.

Effects of acetazolamide on cognitive performance during high-altitude exposure.

High-altitude hypoxia impedes cognitive performance. It is not well known whether the prophylactic use of acetazolamide for altitude sickness can influence cognitive performance at high altitude. When ascending to high altitude locations, one may face medical risks, including cognitive impairment, which may significantly hinder climbing abilities or exploratory behavior. Effective prophylactic drugs have rarely been reported. Because acetazolamide is commonly used to treat acute mountain sickness (AMS), we assessed the potential effects of acetazolamide on cognitive performance during high-altitude exposure. Twenty-one volunteers aged 22-26 years were randomized to receive a 4-day treatment of acetazolamide (125 mg Bid, n=11) or placebo (n=10) before and after air travel from Xianyang (402 m) to Lhasa (3561 m). Neuropsychological performance was assessed using the digit symbol substitution test (DSST), paced auditory serial addition test (PASAT), operation span task, and free recall test at 6, 30, and 54 h after arrival at Lhasa. The Lake Louise Score (LLS) was used to diagnose AMS. At high altitude, acetazolamide impaired rather than improved neuropsychological measures of concentration, cognitive processing speed, reaction time, short-term memory, and working memory, which were assessed by DSST, PASAT, and operation span task at 6 and 30 h after arrival (p<0.05). However, the prophylactic use of acetazolamide was found to reduce the incidence of AMS compared to the placebo (p<0.05). In conclusion, acetazolamide impairs neuropsychological function, at least in part, shortly after the ascent to high altitude.

The role of α-synuclein and tau hyperphosphorylation-mediated autophagy and apoptosis in lead-induced learning and memory injury.

Lead (Pb) is a well-known heavy metal in nature. Pb can cause pathophysiological changes in several organ systems including central nervous system. Especially, Pb can affect intelligence development and the ability of learning and memory of children. However, the toxic effects and mechanisms of Pb on learning and memory are still unclear. To clarify the mechanisms of Pb-induced neurotoxicity in hippocampus, and its effect on learning and memory, we chose Sprague-Dawley rats (SD-rats) as experimental subjects. We used Morris water maze to verify the ability of learning and memory after Pb treatment. We used immunohistofluorescence and Western blotting to detect the level of tau phosphorylation, accumulation of α-synuclein, autophagy and related signaling molecules in hippocampus. We demonstrated that Pb can cause abnormally hyperphosphorylation of tau and accumulation of α-synuclein, and these can induce hippocampal injury and the ability of learning and memory damage. To provide the new insight into the underlying mechanisms, we showed that Grp78, ATF4, caspase-3, autophagy-related proteins were induced and highly expressed following Pb-exposure. But mTOR signaling pathway was suppressed in Pb-exposed groups. Our results showed that Pb could cause hyperphosphorylation of tau and accumulation of α-synuclein, which could induce ER stress and suppress mTOR signal pathway. These can enhance type II program death (autophgy) and type I program death (apoptosis) in hippocampus, and impair the ability of learning and memory of rats. This is the first evidence showing the novel role of autophagy in the neurotoxicity of Pb.

[Effect of compound nutrients on acute immobilization and cold water-immersion stress-induced changes of Th1/Th2 cytokines].

AIM: To investigate the effect of compound nutrients on Th1/Th2 imbalance caused by changes in cytokines of Th cell subsets, interleukin (IL)-2, IL-6 and TNF-α, in rats with acute immobilization and cold water-immersion stress. METHODS: Male SD rats were randomly assigned to three groups including normal control group (C), acute stress group (S) and acute stress+compound nutrients group (S+CN). Stress procedure was the acute immobilization and cold water-immersion. The stress rats were fed water (Group S) or compound nutrient liquid (Group S+CN) by a feeding needle 1 week before acute stress, and then restrained and immersed in cold water for 30 min. The control rats were given water in the same way without stress stimulation. The rats were killed and blood samples were collected 0, 30, 60 and 120 min after stress, respectively. Serum was separated by centrifugation and stored at -70 DegreesCelsius until assayed. The serum levels of IL-2, IL-6 and TNF-α were analyzed by an enzyme-linked immunosorbent assay (ELISA) kit. RESULTS: Acute immobilization and cold water-immersion stress reduced IL-2 level, and increased IL-6 and TNF-α level at different time points (0, 30, 60 and 120 min) after stress, which was most obvious at 30 min. Oral administration (gavage) of compound nutrients was found to moderate the acute immobilization and cold water-immersion stress-induced changes in serum IL-2, IL-6 and TNF-α, which was also most significant at 30 min after stress. CONCLUSION: Complex nutrients can significantly alleviate the changes of Th1/Th2 cytokines in stress rats, including IL-2, IL-6 and TNF-α, which suggests that compound nutrients can improve the immune regulation function of stress rats and restore Th1/Th2 balance. Compound nutrients might enhance the body's anti-stress ability and lighten the stress-related damage, thus being a possible candidate for the therapeutic modulation of stress.

Lead induces dysregulation of iron regulatory protein 1 via the extracellular signal-regulated kinase pathway in human vascular endothelial cells.

Lead (Pb) can target the vascular system for both acute injury and disease promotion. Cellular iron (Fe) disruption may be implicated in Pb vascular toxicity. To investigate the potential involvement of iron response element 1 (IRP1) protein in the vascular endothelium during Pb exposure, human umbilical vein endothelial cells (HUVEC) were treated with different concentrations of lead nitrate, 30 µM iron sulfate, or 100 µM deferoxamine. PD98059, a specific inhibitor of the mitogen-activated protein kinase kinase (MEK) activator, was administered to block the ERK/MAPK pathway. Western blotting was used to detect the expression of IRP1 and p-ERK1/2, and microscopy, and co-immunoprecipitation was used to show the association between IRP1 and p-ERK1/2. In vitro measurements revealed a decrease in IRP1 and activated ERK1/2 in the membrane following Pb treatment. HUVEC treated with PD98059 enhanced the levels of membrane IRP1 and efficiently inhibited the effect of Pb on the levels of membrane IRP1. Partial IRP1 co-localization existed with p-ERK1/2 in the membrane, and Pb treatment produced an obvious decrease in the amount of IRP1 that co-localized with p-ERK1/2. Co-immunoprecipitation further revealed a possible association between IRP-1 and p-ERK1/2. Collectively, Pb specifically induced the dysregulation of IRP1 protein by activating the ERK1/2 signaling pathway in the plasma membrane, indicating a novel role for IRP1 and the ERK/MAPK pathway in vascular endothelial functions.

[Effects of chronic multiple stress on learning and memory and the expression and phosphorylation of cerebral ERK of rats].

OBJECTIVE: To study the effect of chronic multiple stress on learning and memory, and the expression and activation of cerebral extracellular signal-regulated protein kinase (ERK) 1/2 of rats in vivo. METHODS: Ninety male SD rats were divided randomly into control group and stress group. Rats in stress group were stressed everyday by one of the seven stressors including cold exposure, foot shock, white noise, restraint, tail hung up, sleep deprivation, and level shake, and then the ability of learning and memory was determined by Morris water maze test. Serum corticosterone (CORT) level was determined by radioimmunoassay kit. Western blot was performed to determine the expression and phosphorylation of ERK in hippocampus and prefrontal cortex of the brain. RESULTS: The escape latencies of stressed rats were substantially longer than those of the controls in the water maze test (P < 0.01) except a transient recovery at the end of the third week after the stress. The stress also resulted in significantly higher serum CORT level and decreased P-ERK level in hippocampus and prefrontal cortex (PFC) (P < 0.01). Similarly, transient elevation of both CORT and P-ERK levels were observed at the end of the third week. CONCLUSION: Chronic multiple stress can lead to impaired learning and memory by decreasing the phosphorylation of ERK in the hippocampus and PFC. The partial recovery of learning and memory, CORT and P-ERK levels at the end of the third week may due to the adaptation of the rats to stressors.

[Effect of JNK pathway in apoptosis of PC12 cell by MPP+].

OBJECTIVE: To study the toxicity and its mechanisms of 1-methyl-4-phenylpyridinium ion (MPP+) on pheochromocytoma PC12 cells. METHODS: PC12 cells were cultured in vitro, and poisoned by 100, 300, 500 micromol/L MPP+. Western blot was performed to determine the level of phosphorylated c-Jun-N-terminal kinase/stress activated protein kinases (JNK/SAPK). The cells were pretreated with SP600125, an inhibitor of JNK pathway, and then the number of apoptotic cells were counted by using TUNEL stain, observing its influence on cell apoptosis seduced by MPP+. RESULTS: MPP+ poisoning can cause the increase of phosphorylation level of JNK1/2 cells. The usage of JNK pathway inhibitor SP600125 can inhibit the PC12 cell apoptosis seduced by MPP+. CONCLUSION: Activation of JNK pathway may be the important molecular mechanism of PC12 cell apoptosis seduced by MPP+ and of producing dopaminergic neurotoxicity.