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1.
Article in English | MEDLINE | ID: mdl-38607220

ABSTRACT

Objective: This study aims to analyze factors contributing to recurrent respiratory tract infections (RRTIs) in pediatric patients and evaluate the efficacy of pidotimod (PI) treatment. Methods: This study utilized a retrospective cohort design, enrolling a total of 85 children diagnosed with RRTIs between September 2020 and September 2022, alongside 54 healthy children. Logistic regression analysis was employed to identify factors contributing to RRTI occurrence. Among the participants, 40 children underwent conventional treatment (control group), while 45 received PI treatment (research group). Comparative analyses were conducted to assess clinical efficacy and adverse effects between the two treatment groups. Results: The history of family members' smoking and parental allergy emerged as independent risk factors for RRTIs (P < .05, OR>1), whereas parental education level, outdoor activity, and micronutrient intake were identified as independent protective factors for RRTIs (P < .05, OR<1). Symptoms such as cough, fever, rhonchi, moist rales, and tonsillar enlargement resolved significantly faster in the research group compared to the control group (P < .05). Additionally, the research group exhibited reduced infection duration and fewer recurrent infections (P < .05). Following treatment, the overall treatment efficacy was superior in the research group compared to the control group (P < .05), with no significant difference in the incidence of adverse effects (P > .05). Post-treatment, levels of CD3+, CD4+, and CD4+/CD8+ were elevated in the research group compared to the control group, while CD8+ levels were lower (P < .05). Conclusions: Daily outdoor activity among children, family members' history of smoking, parental allergy history, education level, and micronutrient intake emerged as independent factors influencing pediatric RRTIs. Furthermore, PI was identified as a significant treatment option for RRTIs.

2.
Front Immunol ; 14: 1163967, 2023.
Article in English | MEDLINE | ID: mdl-37325670

ABSTRACT

Advanced hepatocellular carcinoma (HCC) is a formidable public health problem with limited curable treatment options. Axitinib, an oral tyrosine kinase inhibitor, is a potent and selective second-generation inhibitor of vascular endothelial growth factor receptor (VEGFR) 1, 2, and 3. This anti-angiogenic drug was found to have promising activity in various solid tumors, including advanced HCC. At present, however, there is no relevant review article that summarizes the exact roles of axitinib in advanced HCC. In this review, 24 eligible studies (seven studies in the ClinicalTrials, eight experimental studies, and nine clinical trials) were included for further evaluation. The included randomized or single-arm phase II trials indicated that axitinib could not prolong the overall survival compared to the placebo for the treatment of advanced HCC, but improvements in progression free survival and time to tumor progression were observed. Experimental studies showed that the biochemical effects of axitinib in HCC might be regulated by its associated genes and affected signaling cascades (e.g. VEGFR2/PAK1, CYP1A2, CaMKII/ERK, Akt/mTor, and miR-509-3p/PDGFRA). FDA approved sorafenib combined with nivolumab (an inhibitor of PD-1/PD-L1) as the first line regimen for the treatment of advanced HCC. Since both axitinib and sorafenib are tyrosine kinase inhibitors as well as the VEGFR inhibitors, axitinib combined with anti-PDL-1/PD-1 antibodies may also exhibit tremendous potential in anti-tumoral effects for advanced HCC. The present review highlights the current clinical applications and the molecular mechanisms of axitinib in advanced HCC. To move toward clinical applications by combining axitinib and other treatments in advanced HCC, more studies are still warranted in the near future.


Subject(s)
Carcinoma, Hepatocellular , Liver Neoplasms , Humans , Axitinib/therapeutic use , Carcinoma, Hepatocellular/pathology , Sorafenib/therapeutic use , Vascular Endothelial Growth Factor A , Programmed Cell Death 1 Receptor , Indazoles/pharmacology , Liver Neoplasms/pathology , Imidazoles/pharmacology
3.
Nat Commun ; 13(1): 561, 2022 01 28.
Article in English | MEDLINE | ID: mdl-35091578

ABSTRACT

Plants use nitrate and ammonium as major nitrogen (N) sources, each affecting root development through different mechanisms. However, the exact signaling pathways involved in root development are poorly understood. Here, we show that, in Arabidopsis thaliana, either disruption of the cell wall-localized ferroxidase LPR2 or a decrease in iron supplementation efficiently alleviates the growth inhibition of primary roots in response to NH4+ as the N source. Further study revealed that, compared with nitrate, ammonium led to excess iron accumulation in the apoplast of phloem in an LPR2-dependent manner. Such an aberrant iron accumulation subsequently causes massive callose deposition in the phloem from a resulting burst of reactive oxygen species, which impairs the function of the phloem. Therefore, ammonium attenuates primary root development by insufficiently allocating sucrose to the growth zone. Our results link phloem iron to root morphology in response to environmental cues.


Subject(s)
Ammonium Compounds/metabolism , Arabidopsis/metabolism , Iron/metabolism , Nitrogen/metabolism , Phloem/metabolism , Plant Roots/metabolism , Arabidopsis/genetics , Arabidopsis/growth & development , Arabidopsis Proteins/genetics , Arabidopsis Proteins/metabolism , Cell Wall/genetics , Cell Wall/metabolism , Ceruloplasmin/genetics , Ceruloplasmin/metabolism , Gene Expression Regulation, Developmental , Gene Expression Regulation, Plant , Glucans/metabolism , Mutation , Nitrates/metabolism , Plant Roots/genetics , Plant Roots/growth & development , Plants, Genetically Modified , Reactive Oxygen Species/metabolism , Seedlings/genetics , Seedlings/growth & development , Seedlings/metabolism
4.
Drug Des Devel Ther ; 15: 3749-3764, 2021.
Article in English | MEDLINE | ID: mdl-34511884

ABSTRACT

BACKGROUND AND AIM: Pancreatic cancer is one of the most malignant tumors worldwide. Zuojin pills (ZJP), a traditional Chinese medicine (TCM) formula, which can treat a variety of cancers. However, the active compounds present in ZJP and the potential mechanisms through which ZJP acts against pancreatic cancer have not been thoroughly investigated. METHODS: Data on pancreatic cancer-related genes, bioactive compounds, and potential targets of ZJP were downloaded from public databases. Bioinformatics analysis, including protein-protein interaction (PPI), Gene Ontology (GO), and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses, was conducted to identify important components, potential targets, and signaling pathways through which ZJP affects pancreatic cancer. The results of this analysis were verified by in vitro experiments. RESULTS: The network pharmacology analysis results showed that 41 compounds and 130 putative target genes of ZJP were associated with anti-pancreatic cancer effects. ZJP may exert its inhibitory effects against pancreatic cancer by acting on key targets such as JUN, TP53, and MAPK1. Moreover, KEGG analysis indicated that the anti-pancreatic cancer effect of ZJP was mediated by multiple pathways, such as the PI3K-AKT, IL-17, TNF, HIF-1, and P53 signaling pathways. Among these, the PI3K-AKT signaling pathway, which included the highest number of enriched genes, may play a more important role in treating pancreatic cancer. The in vitro results showed that ZJP significantly inhibits the cell cycle and cell proliferation through the PI3K/AKT/caspase pathway and that it can induce apoptosis of pancreatic cancer cells, consistent with the results predicted by network pharmacological methods. CONCLUSION: This study preliminarily investigated the pharmacological effects of ZJP, which appear to be mediated by multiple compounds, targets and pathways, and its potential therapeutic effect on pancreatic cancer. Importantly, our work provides a promising approach for the identification of compounds in TCM and the characterization of therapeutic mechanisms.


Subject(s)
Antineoplastic Agents, Phytogenic/pharmacology , Drugs, Chinese Herbal/pharmacology , Pancreatic Neoplasms/drug therapy , Apoptosis/drug effects , Cell Cycle/drug effects , Cell Line, Tumor , Cell Proliferation/drug effects , Humans , Network Pharmacology , Pancreatic Neoplasms/genetics , Pancreatic Neoplasms/pathology , Phosphatidylinositol 3-Kinase/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Signal Transduction/drug effects
5.
Sci Total Environ ; 798: 149285, 2021 Dec 01.
Article in English | MEDLINE | ID: mdl-34340090

ABSTRACT

Identifying the genes that affect cadmium (Cd) accumulation in plants is a prerequisite for minimizing dietary Cd uptake from contaminated edible parts of plants by genetic engineering. This study showed that Cd stress inhibited the expression of FERONIA (FER) gene in the roots of wild-type Arabidopsis. Knockout of FER in fer-4 mutants downregulated the Cd-induced expression of several genes related to iron (Fe) uptake, including IRT1, bHLH38, NRAMP1, NRAMP3, FRO2 andFIT. In addition, the Cd concentration in fer-4 mutant roots reduced to approximately half of that in the wild-type seedlings. As a result, the Cd tolerance of fer-4 was higher. Furthermore, increased Fe supplementation had little effect on the Cd tolerance of fer-4 mutants, but clearly improved the Cd tolerance of wild-type seedlings, showing that the alleviation of Cd toxicity by Fe depends on the action of FER. Taken together, the findings demonstrate that the knockout of FER might provide a strategy to reduce Cd contamination and improve the Cd tolerance in plants by regulating the pathways related to Fe uptake.


Subject(s)
Arabidopsis Proteins , Arabidopsis , Arabidopsis/genetics , Arabidopsis Proteins/genetics , Cadmium/toxicity , Iron , Plant Roots
6.
World J Gastrointest Surg ; 13(2): 176-186, 2021 Feb 27.
Article in English | MEDLINE | ID: mdl-33643537

ABSTRACT

BACKGROUND: Whether regional lymphadenectomy (RL) should be routinely performed in patients with T1b gallbladder cancer (GBC) remains a subject of debate. AIM: To investigate whether RL can improve the prognosis of patients with T1b GBC. METHODS: We studied a multicenter cohort of patients with T1b GBC who underwent surgery between 2008 and 2016 at 24 hospitals in 13 provinces in China. The log-rank test and Cox proportional hazards model were used to compare the overall survival (OS) of patients who underwent cholecystectomy (Ch) + RL and those who underwent Ch only. To investigate whether combined hepatectomy (Hep) improved OS in T1b patients, we studied patients who underwent Ch + RL to compare the OS of patients who underwent combined Hep and patients who did not. RESULTS: Of the 121 patients (aged 61.9 ± 10.1 years), 77 (63.6%) underwent Ch + RL, and 44 (36.4%) underwent Ch only. Seven (9.1%) patients in the Ch + RL group had lymph node metastasis. The 5-year OS rate was significantly higher in the Ch + RL group than in the Ch group (76.3% vs 56.8%, P = 0.036). Multivariate analysis showed that Ch + RL was significantly associated with improved OS (hazard ratio: 0.51; 95% confidence interval: 0.26-0.99). Among the 77 patients who underwent Ch + RL, no survival improvement was found in patients who underwent combined Hep (5-year OS rate: 79.5% for combined Hep and 76.1% for no Hep; P = 0.50). CONCLUSION: T1b GBC patients who underwent Ch + RL had a better prognosis than those who underwent Ch. Hep + Ch showed no improvement in prognosis in T1b GBC patients. Although recommended by both the National Comprehensive Cancer Network and Chinese Medical Association guidelines, RL was only performed in 63.6% of T1b GBC patients. Routine Ch + RL should be advised in T1b GBC.

7.
BMJ Open ; 11(2): e038634, 2021 02 16.
Article in English | MEDLINE | ID: mdl-33593763

ABSTRACT

INTRODUCTION: Gallbladder cancer (GBC), the sixth most common gastrointestinal tract cancer, poses a significant disease burden in China. However, no national representative data are available on the clinical characteristics, treatment and prognosis of GBC in the Chinese population. METHODS AND ANALYSIS: The Chinese Research Group of Gallbladder Cancer (CRGGC) study is a multicentre retrospective registry cohort study. Clinically diagnosed patient with GBC will be identified from 1 January 2008 to December, 2019, by reviewing the electronic medical records from 76 tertiary and secondary hospitals across 28 provinces in China. Patients with pathological and radiological diagnoses of malignancy, including cancer in situ, from the gallbladder and cystic duct are eligible, according to the National Comprehensive Cancer Network 2019 guidelines. Patients will be excluded if GBC is the secondary diagnosis in the discharge summary. The demographic characteristics, medical history, physical examination results, surgery information, pathological data, laboratory examination results and radiology reports will be collected in a standardised case report form. By May 2021, approximately 6000 patient with GBC will be included. The clinical follow-up data will be updated until 5 years after the last admission for GBC of each patient. The study aimed (1) to depict the clinical characteristics, including demographics, pathology, treatment and prognosis of patient with GBC in China; (2) to evaluate the adherence to clinical guidelines of GBC and (3) to improve clinical practice for diagnosing and treating GBC and provide references for policy-makers. ETHICS AND DISSEMINATION: The protocol of the CRGGC has been approved by the Committee for Ethics of Xinhua Hospital, Shanghai Jiao Tong University School of Medicine (SHEC-C-2019-085). All results of this study will be published in peer-reviewed journals and presented at relevant conferences. TRIAL REGISTRATION NUMBER: NCT04140552, Pre-results.


Subject(s)
Gallbladder Neoplasms , China/epidemiology , Gallbladder Neoplasms/diagnosis , Gallbladder Neoplasms/epidemiology , Gallbladder Neoplasms/therapy , Humans , Registries
8.
Front Immunol ; 12: 792781, 2021.
Article in English | MEDLINE | ID: mdl-34975896

ABSTRACT

Hepatocellular carcinoma (HCC) is the third leading cause of cancer-related deaths worldwide and is increasing in incidence. Local ablative therapy plays a leading role in HCC treatment. Radiofrequency (RFA) is one of the first-line therapies for early local ablation. Other local ablation techniques (e.g., microwave ablation, cryoablation, irreversible electroporation, phototherapy.) have been extensively explored in clinical trials or cell/animal studies but have not yet been established as a standard treatment or applied clinically. On the one hand, single treatment may not meet the needs. On the other hand, ablative therapy can stimulate local and systemic immune effects. The combination strategy of immunotherapy and ablation is reasonable. In this review, we briefly summarized the current status and progress of ablation and immunotherapy for HCC. The immune effects of local ablation and the strategies of combination therapy, especially synergistic strategies based on biomedical materials, were discussed. This review is hoped to provide references for future researches on ablative immunotherapy to arrive to a promising new era of HCC treatment.


Subject(s)
Ablation Techniques , Carcinoma, Hepatocellular/therapy , Immunotherapy , Liver Neoplasms/therapy , Ablation Techniques/adverse effects , Animals , Antineoplastic Agents, Immunological/therapeutic use , Cancer Vaccines/therapeutic use , Carcinoma, Hepatocellular/immunology , Carcinoma, Hepatocellular/pathology , Combined Modality Therapy , Humans , Immune Checkpoint Inhibitors/therapeutic use , Immunotherapy/adverse effects , Immunotherapy, Adoptive , Liver Neoplasms/immunology , Liver Neoplasms/pathology , Nanomedicine , Treatment Outcome
9.
JCI Insight ; 5(8)2020 04 23.
Article in English | MEDLINE | ID: mdl-32213714

ABSTRACT

Over 55,000 people in the United States are diagnosed with pancreatic ductal adenocarcinoma (PDAC) yearly, and fewer than 20% of these patients survive a year beyond diagnosis. Chemotherapies are considered or used in nearly every PDAC case, but there is limited understanding of the complex signaling responses underlying resistance to these common treatments. Here, we take an unbiased approach to study protein kinase network changes following chemotherapies in patient-derived xenograft (PDX) models of PDAC to facilitate design of rational drug combinations. Proteomics profiling following chemotherapy regimens reveals that activation of JNK-JUN signaling occurs after 5-fluorouracil plus leucovorin (5-FU + LEU) and FOLFOX (5-FU + LEU plus oxaliplatin [OX]), but not after OX alone or gemcitabine. Cell and tumor growth assays with the irreversible inhibitor JNK-IN-8 and genetic manipulations demonstrate that JNK and JUN each contribute to chemoresistance and cancer cell survival after FOLFOX. Active JNK1 and JUN are specifically implicated in these effects, and synergy with JNK-IN-8 is linked to FOLFOX-mediated JUN activation, cell cycle dysregulation, and DNA damage response. This study highlights the potential for JNK-IN-8 as a biological tool and potential combination therapy with FOLFOX in PDAC and reinforces the need to tailor treatment to functional characteristics of individual tumors.


Subject(s)
Antineoplastic Agents/pharmacology , Carcinoma, Pancreatic Ductal , Drug Resistance, Neoplasm/drug effects , Pancreatic Neoplasms , Animals , Antineoplastic Combined Chemotherapy Protocols , Drug Evaluation, Preclinical , Fluorouracil/pharmacology , Humans , Leucovorin , MAP Kinase Kinase 4/antagonists & inhibitors , Mice , Mitogen-Activated Protein Kinase 8/antagonists & inhibitors , Organoplatinum Compounds , Xenograft Model Antitumor Assays
10.
Cell Discov ; 3: 17038, 2017.
Article in English | MEDLINE | ID: mdl-29387450

ABSTRACT

Imprinted genes are vulnerable to environmental influences during early embryonic development, thereby contributing to the onset of disease in adulthood. Monoallelic methylation at several germline imprints has been reported as DNMT1-dependent. However, which of these two epigenetic attributes, DNMT1-dependence or allelic methylation, renders imprinted genes susceptible to environmental stressors has not been determined. Herein, we developed a new approach, referred to as NORED, to identify 2468 DNMT1-dependent DNA methylation patterns in the mouse genome. We further developed an algorithm based on a genetic variation-independent approach (referred to as MethylMosaic) to detect 2487 regions with bimodal methylation patterns. Two approaches identified 207 regions, including known imprinted germline allele-specific methylation patterns (ASMs), that were both NORED and MethylMosaic regions. Examination of methylation in four independent mouse embryonic stem cell lines shows that two regions identified by both NORED and MethylMosaic (Hcn2 and Park7) did not display parent-of-origin-dependent allelic methylation. In these four F1 hybrid cell lines, genetic variation in Cast allele at Hcn2 locus introduces a transcription factor binding site for MTF-1 that may predispose Cast allelic hypomethylation in a reciprocal cross with either C57 or 129 strains. In contrast, each allele of Hcn2 ASM in J1 inbred cell line and Park7 ASM in four F1 hybrid cell lines seems to exhibit similar propensity to be either hypo- or hypermethylated, suggesting a 'random, switchable' ASM. Together with published results, our data on ASMs prompted us to propose a hypothesis of regional 'autosomal chromosome inactivation (ACI)' that may control a subset of autosomal genes. Therefore, our results open a new avenue to understand monoallelic methylation and provide a rich resource of candidate genes to examine in environmental and nutritional exposure models.

11.
Sci Rep ; 5: 10746, 2015 Jun 15.
Article in English | MEDLINE | ID: mdl-26073914

ABSTRACT

Cell wall is the major component of root apoplast which is the main reservoir for iron in roots, while nitric oxide (NO) is involved in regulating the synthesis of cell wall. However, whether such regulation could influence the reutilization of iron stored in root apoplast remains unclear. In this study, we observed that iron deficiency elevated NO level in tomato (Solanum lycopersicum) roots. However, application of S-nitrosoglutathione, a NO donor, significantly enhanced iron retention in root apoplast of iron-deficient plants, accompanied with a decrease of iron level in xylem sap. Consequently, S-nitrosoglutathione treatment increased iron concentration in roots, but decreased it in shoots. The opposite was true for the NO scavenging treatment with 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (cPTIO). Interestingly, S-nitrosoglutathione treatment increased pectin methylesterase activity and decreased degree of pectin methylation in root cell wall of both iron-deficient and iron-sufficient plants, which led to an increased iron retention in pectin fraction, thus increasing the binding capacity of iron to the extracted cell wall. Altogether, these results suggested that iron-deficiency-induced elevation of NO increases iron immobilization in root apoplast by decreasing pectin methylation in cell wall.


Subject(s)
Cell Wall/drug effects , Iron/metabolism , Nitric Oxide/biosynthesis , Plant Roots/drug effects , S-Nitrosoglutathione/chemistry , Solanum lycopersicum/drug effects , Benzoates/pharmacology , Carboxylic Ester Hydrolases/metabolism , Cell Wall/metabolism , Free Radical Scavengers/pharmacology , Imidazoles/pharmacology , Solanum lycopersicum/metabolism , Nitric Oxide/agonists , Nitric Oxide/antagonists & inhibitors , Nitric Oxide Donors/chemistry , Nitric Oxide Donors/pharmacology , Pectins/metabolism , Plant Proteins/metabolism , Plant Roots/metabolism , S-Nitrosoglutathione/pharmacology , Xylem/drug effects , Xylem/metabolism
12.
Environ Sci Pollut Res Int ; 20(11): 8237-44, 2013 Nov.
Article in English | MEDLINE | ID: mdl-23686758

ABSTRACT

The effects of plant debris on phosphorus sorption by anoxic sediment were investigated. Addition of plant debris significantly enhanced the decrease of soluble relative phosphorus (SRP) in overlying water at both 10 and 30 °C during the 30-day investigation. Both cellulose and glucose, two typical plant components, also clearly enhanced the SRP decrease in anoxic overlying water. The measurement of phosphorus (P) fractions in sediment revealed that the levels of unstable P forms were decreased by plant debris addition, whereas the opposites were true for stable P forms. However, under sterilized condition, plant debris/glucose addition has no effect on the SRP decrease in overlying water. Overall, our results suggested that plant debris improve P sorption into sediment under anoxic condition through a microorganism-mediated mechanism.


Subject(s)
Geologic Sediments/chemistry , Phosphorus/analysis , Plants/chemistry , Water Pollutants, Chemical/analysis , Fresh Water/chemistry , Phosphorus/metabolism , Waste Products , Water Pollutants, Chemical/metabolism
13.
Food Chem Toxicol ; 46(6): 2054-61, 2008 Jun.
Article in English | MEDLINE | ID: mdl-18331777

ABSTRACT

Over consumption of copper (Cu) from food and beverages is detrimental to human health. In this study, we investigated Cu accumulation in tea leaves produced in Yuyao County in China. Copper concentrations in all tea leaves sampled from tea gardens were below 60mgkg(-1), the permissible level given by the Chinese Ministry of Health; however, 15% of the samples were over 15mgkg(-1), the allowable level of 'green food' as defined by the Chinese Ministry of Agriculture. These observations indicate that Cu concentrations in tea leaves from the investigated producing areas are acceptable, but still a concern. To understand what factors affect the Cu accumulation in the tea leaves, we further analyzed soils from the tea gardens for Cu availability, pH and organic matter content. The Cu availability in soil was found to be closely correlated with the soil's H+ activity, followed by organic matter content. The soils in the tea gardens were also found to be severely acidic with the lowest pH of 3.58. The tea garden soils, if fertilized with animal manure, could also contribute to the risk of Cu contamination. Additionally, Cu concentrations in the final products of tea leaves were greatly increased by the machinery processing in factories that used copper boards at the twisting stage. In one factory, the Cu level was increased by 32.1mgkg(-1). This study suggests that both edaphic and non-edaphic factors can contribute to the final Cu accumulation in tea leaves used by consumers.


Subject(s)
Copper/analysis , Tea/chemistry , China , Hydrogen-Ion Concentration , Plant Leaves/chemistry , Soil/analysis
14.
Chemosphere ; 61(5): 726-32, 2005 Nov.
Article in English | MEDLINE | ID: mdl-16219507

ABSTRACT

Recent tests have detected high lead (Pb) concentrations in some commercial brands of tea leaves and this finding has raised concerns due to the possible health-related problems associated with Pb poisoning. In present research, we investigated the Pb contamination in tea leaves produced in Zhejiang province in China. Pb concentrations in all tea leaves sampled were below 5 mg/kg, the permissible levels given by Chinese Ministry of Agriculture, indicating that Pb contamination in this province is not excessive. We then investigated the non-edaphic factors that may potentially contribute to Pb accumulation in tea leaves. Pb concentration in tea leaves was found to be positively correlated with the industrialization level of a district (R = 0.83, the significant level at P < 0.05), and greater amounts of Pb were washed from the leaves of plants in districts with more industrial activity. This suggests that Pb accumulation in tea leaves could, in part, be attributed to industrial activity through the precipitation of atmospheric Pb. Furthermore greater amounts of Pb were washed from the leaves of plants growing near road than those growing farther away from road. This trend indicates that automobile activity was another likely contributor to Pb accumulation in tea. Pb content of green tea was also affected by the processing of the leaves in the factory. In particular the twisting and water-removal stages caused increases in Pb content in the tea product. This study suggests that non-edaphic factors also contribute to the Pb accumulation in tea.


Subject(s)
Air Pollutants/analysis , Camellia sinensis/chemistry , Lead/analysis , Plant Leaves/chemistry , Soil Pollutants/analysis , China , Environmental Monitoring , Food Contamination , Food Handling , Industry , Vehicle Emissions
15.
Chemosphere ; 59(8): 1151-9, 2005 May.
Article in English | MEDLINE | ID: mdl-15833489

ABSTRACT

The consumption of heavy metals is detrimental to human health and most countries restrict the concentration of metals such as lead (Pb) in food and beverages. Recent tests have detected high Pb concentrations in certain commercial brands of tea leaves and this finding has raised concerns for both producers and consumers. To investigate what factors may be contributing to the increase in Pb accumulation in the tea leaves we collected tea leaves and soils from tea producing areas and analyzed them for Pb concentration, pH and organic matter content. The result showed the Pb concentration of 47% investigated tea leaves samples was beyond 2 mg kg(-1), the permissible levels given by China. The total Pb concentration in the surface and subsurface soil layers averaged 36.4 and 32.2 mg kg(-1), respectively which fall below of the 60 mg kg(-1) limit provided for organic tea gardens in China. The pH of the tea garden soils was severely acidic with the lowest pH of 3.37. Soils under older tea gardens tended to have a lower pH and a higher Pb bioavailability which was defined as the amount of lead extracted by CaCl2 solution than those under younger tea gardens. We found that the concentration of bioavailable Pb and the percentage of bioavailable Pb (bioavailable Pb relative to total Pb concentration) were positively correlated with soil H+ activity and soil organic matter content, and the organic matter accumulation contribute more effects on Pb bioavailability in these two factors. We conclude that soil acidification and organic matter accumulation could contribute to increasing Pb bioavailability in soil and that these could increase Pb uptake and accumulation in the tea leaves.


Subject(s)
Camellia sinensis/metabolism , Lead/analysis , Lead/pharmacokinetics , Plant Leaves/metabolism , Soil Pollutants/analysis , Biological Availability , Camellia sinensis/chemistry , China , Hydrogen-Ion Concentration , Plant Leaves/chemistry , Spectrophotometry, Atomic
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