A sustainable phosphorus management in agriculture: Assessing trade-offs between human health risks and nutritional yield regarding heavy metals in maize grain.

High-quality products in sustainable agriculture require both limited health risks and sufficient dietary nutrients. Phosphorus (P) as a finite and non-renewable resource is widely used in agriculture, usually exerting influence on the accumulation of heavy metals (HMs) in soil and crops. The present research explores, for the first time, the combined effects of long-term P fertilizer and repeated zinc (Zn) application in field on the human health risks and nutritional yield regarding trace elements in maize grain. A field experiment was conducted using maize with six P application rates (0, 12.5, 25, 50, 100, and 200 kg P ha-1) and two Zn application rates (0 and 11.4 kg Zn ha-1). The results showed that the concentrations of Zn, copper (Cu), and lead (Pb) in the maize grain were significantly affected by P application and can be further affected by Zn application. The concentrations of chromium (Cr) and arsenic (As) showed opposite tendency as affected by P fertilizer rates while did not affected by additional Zn application. Zn application decreased the cadmium (Cd) concentration at high P levels and Pb concentration at low P levels, particularly. No HMs contamination or direct health risk was found in maize grain after receiving long-term P and repeated Zn fertilizer. The threshold hazard quotient of an individual and all investigated HMs in this study were acceptable for human digestion of maize grain. While the carcinogenic risk of Cr was non-negligible in case of maize was taken as one of daily staple food for local residents. Combination use of P (25 kg ha-1) and Zn fertilizer on maize enhanced its nutritional supply ability regarding Zn and Cu, and simultaneously mitigated potential human health risks associated with Cd and Pb.

Health risk assessment associated with heavy metal accumulation in wheat after long-term phosphorus fertilizer application.

Phosphorus (P) fertilizer is widely used to increase wheat yield. However, it remains unclear whether prolonged intake of wheat grain that received long-term P application may promote human health risks by influencing heavy metal(loid)s (HMs) accumulation. A 10-year field experiment was conducted to evaluate the effects of continuous P application (0, 25, 50, 100, 200, and 400 kg P ha-1) on human health risks of HMs, including zinc (Zn), copper (Cu), cadmium (Cd), lead (Pb), arsenic (As), nickel (Ni), and chromium (Cr), by ingesting wheat grain. The results showed that P application facilitated Zn, Pb, Cd, and As accumulation in the topsoil. The Zn, Cu, Pb, and Ni concentrations in grain were decreased, while Cd and As were increased by P application. All HMs concentrations of both soil and grain were in the ranges of corresponding safety thresholds at different P levels. The accumulation abilities of Zn, Cu, Pb, and Ni from soil and straw to grain were suppressed by P addition while of As was enhanced. There was no significant difference in the hazard index (HI) of the investigated HMs in all treatments except 25 kg ha-1. The threshold cancer risk (TCR) associated with As and Cd was enhanced, while that of Pb was alleviated as P application increased. Behaviors of Cr from soil to wheat and to humans were not affected by P application. Phosphorus application at a rate of 50 kg ha-1 decreased total non-cancer and cancer risks by 15% and 21%, respectively, for both children and adults, compared to the highest value. In conclusion, long-term optimal application of 50 kg P ha-1 to wheat did not result in additional adverse effects on the total non-carcinogenic or carcinogenic risk caused by the studied HMs to humans through the ingestion of wheat grain.

Physiological and developmental traits associated with the grain yield of winter wheat as affected by phosphorus fertilizer management.

Although researchers have determined that attaining high grain yields of winter wheat depends on the spike number and the shoot biomass, a quantitative understanding of how phosphorus (P) nutrition affects spike formation, leaf expansion and photosynthesis is still lacking. A 3-year field experiment with wheat with six P application rates (0, 25, 50, 100, 200, and 400 kg P ha-1) was conducted to investigate this issue. Stem development and mortality, photosynthetic parameters, dry matter accumulation, and P concentration in whole shoots and in single tillers were studied at key growth stages for this purpose. The results indicated that spike number contributed the most to grain yield of all the yield components in a high-yielding (>8 t/ha) winter wheat system. The main stem (MS) contributed 79% to the spike number and tiller 1 (T1) contributed 21%. The 2.7 g kg-1 tiller P concentration associated with 15 mg kg-1 soil Olsen-P at anthesis stage led to the maximal rate of productive T1s (64%). The critical shoot P concentration that resulted in an adequate product of Pn and LAI was identified as 2.1 g kg-1. The thresholds of shoot P concentration that led to the maximum productive ability of T1 and optimal canopy photosynthetic capacity at anthesis were very similar. In conclusion, the thresholds of soil available P and shoot P concentration in whole plants and in single organs (individual tillers) were established for optimal spike formation, canopy photosynthetic capacity, and dry matter accumulation. These thresholds could be useful in achieving high grain yields while avoiding excessive P fertilization.

A distinct serum metabolic signature of distant metastatic papillary thyroid carcinoma.

BACKGROUND: Although the incidence rate for thyroid cancer seems to have begun stabilizing in recent years, an increased rate of advanced stage of this disease has been reported. Additionally, distant metastasis is one of the most important prognostic factors of patients with papillary thyroid carcinoma (PTC). Unfortunately, the underlying mechanisms of distant metastasis, as well as cell status like metabolism changes in distant metastatic tumours have not been clearly elucidated. OBJECTIVE: To identify serum metabolic signature of distant metastatic PTC. DESIGN, PATIENTS AND MEASUREMENTS: In this study, gas chromatography-time-of-flight mass spectrometry (GC-TOF-MS) was used to analyse the serum from 77 patients diagnosed with PTC (37 in distant metastasis group and 40 in ablation group). Principal component analysis (PCA) and orthogonal partial least-squares-discriminant analysis (OPLS-DA) scores plots were used to analyse the data. RESULTS: Principal component analysis and OPLS-DA analyses demonstrated an evident trend of separation between 40 serum samples from the ablation group and 37 samples from distant metastasis group. A total of 31 metabolites were identified, which are related to amino acid, lipid, glucose, vitamin metabolism and diet/gut microbiota interaction. Pathway analysis showed "alanine, aspartate and glutamate metabolism" and "inositol phosphate metabolism" were the most relevant pathways. CONCLUSION: Serum metabolomics profiling could significantly discriminate papillary thyroid cancer patients according to distant metastasis. Potential metabolic aberration in distant metastatic PTC could be involved in different biological behaviours of tumour cells including proliferation, invasion/migration and immune escape. Diet/gut microbiota-produced metabolites could play an important role in these effects. This work may provide new clues to find the underlying mechanisms regarding the distant metastasis of PTC as well as potential adjuvant therapy targets.

Liuwei Dihuang pill treats diabetic nephropathy in rats by inhibiting of TGF-ß/SMADS, MAPK, and NF-kB and upregulating expression of cytoglobin in renal tissues.

Liuwei Dihuang pill (LDP) was assessed for its effects on renal deficiency.90 STZ induced DN rats were divided into groups (n = 22) without treatment (STZ) and LDP treated (STZ-L) (n = 23), Zhenwu decoction treated (STZ-Z) (n = 22), and valsartan treated (STZ-V) (n = 23) groups, with 16 normal control rats. Total urine protein (TP), blood urea nitrogen (BUN), and serum creatinine (Cr) were measured. Superoxide dismutase (SOD), nitric oxide synthase (NOS), and malondialdehyde (MDA) concentrations as well as expression/phosphorylation of SMAD3, SMAD2, and α-SMA, TGF-ß, RI /II, P38, ERK, and NF-kB in renal tissues were determined. In vitro experiments analyzed the effect of enhanced TGF-ß containing rat serums of the STZ groups on mesangial cells with and without transient transfection with a cytoglobin-containing plasmid.LDP treatment reduced the kidney coefficient, serum creatinine, blood urea nitrogen, and urine protein and prevented pathological changes. Expression of SOD and NOS in kidney tissue was increased but MDA expression reduced. LDP modulated multiple pathways, and its administration inhibited the phosphorylation of SMADS, ERK, p38, and the expression of NF-kB, α-SMA, and TGF-ß RI/II, and upregulated the expression of cytoglobin. In vitro studies revealed that overexpression of cytoglobin suppressed phosphorylation of Smad2, ERK, and p38 induced by TGF-ß and expression of NF-kB, α-SMA, and TGF-ß RI.LDP prevented renal fibrosis and protected glomerular mesangial cells by upregulation of cytoglobin and suppression of multiple pathways involving TGF-ß/SMADS, MAPK, NF-kB signaling.

Down-regulation of phosphoglucose isomerase/autocrine motility factor enhances gensenoside Rh2 pharmacological action on leukemia KG1α cells.

AIMS AND BACKGROUND: Ginsenoside Rh2, which exerts the potent anticancer action both in vitro and in vivo, is one of the most well characterized ginsenosides extracted from ginseng. Although its effects on cancer are significant, the underlying mechanisms remain unknown. In this study, we sought to elucidate possible links between ginsenoside Rh2 and phosphoglucose isomerase/autocrine motility factor (PGI/AMF). METHODS: KG1α, a leukemia cell line highly expressing PGI/AMF was assessed by western blot analysis and reverse transcription- PCR (RT-PCR) assay after transfection of a small interfering (si)-RNA to silence PGI/AMF. The effect of PGI/ AMF on proliferation was measured by typan blue assay and antibody array. A cell counting kit (CCK)-8 and flow cytometry (FCM) were adopted to investigate the effects of Rh2 on PGI/AMF. The relationships between PGI/AMF and Rh2 associated with Akt, mTOR, Raptor, Rag were detected by western blot analysis. RESULTS: KG1α cells expressed PGI/AMF and its down-regulation significantly inhibited proliferation. The antibody array indicated that the probable mechanism was reduced expression of PARP, State1, SAPK/JNK and Erk1/2, while those of PRAS40 and p38 were up-regulated. Silencing of PGI/AMF enhanced the sensibility of KG1α to Rh2 by suppressing the expression of mTOR, Raptor and Akt. CONCLUSION: These results suggested that ginsenoside Rh2 suppressed the proliferation of KG1α, the same as down-regulation of PGI/AMF. Down-regulation of PGI/ AMF enhanced the pharmacological effects of ginsenoside Rh2 on KG1α by reducing Akt/mTOR signaling.

[Effects of Chinese herbal medicine Liuwei Dihuang Pill and its main monomer catalpol on transforming growth factor-ß1/Smad pathway in HK-2 cells].

OBJECTIVE: To observe the effects of sera containing Liuwei Dihuang Pill (LDP), a compound traditional Chinese herbal medicine, and its monomer catalpol on transforming growth factor-ß1 (TGF-ß1)/Smad pathway in HK-2 cells. METHODS: Wistar rats were intragastrically administered with LDP twice daily for 3 days and then sera were obtained. HK-2 cells were cultured at different concentrations of serum containing LDP. Lactate dehydrogenase (LDH) activity in the medium and cell activity, tested by methyl thiazolyl tetrazolium (MTT) method, were combined to determine the best concentration of the pill. Hepatocyte growth factor (HGF) was used as a positive control, while Western blotting was applied to observe the effects of sera containing LDP and catalpol on Smad2 phosphorylation and protein expressions of Smad2, Smad7 and SnoN. RESULTS: The 10% concentration of serum containing LDP was selected to carry out this study, as it showed no change of LDH activity in the medium and vitality of cells cultured with serum from normal rats. Similar to the mechanisms of HGF, the 10% concentration of serum containing LDP significantly inhibited the phosphorylation of Smad2 protein and up-regulated the expression of the Smad transcriptional co-repressor SnoN in TGF-ß1-stimulated HK-2 cells. Catalpol inhibited phosphorylation of Smad2 without affecting SnoN protein expression. Neither serum containing LDP nor catalpol showed typical regulation effects on Smad7 expression in TGF-ß1-stimulated HK-2 cells. CONCLUSION: Serum containing LDP at 10% concentration has a potent antagonistic action on TGF-ß1/Smad pathway in TGF-ß1-stimulated HK-2 cells, which is similar to HGF. Catalpol is one of the most important monomers and plays a key role in LDP.

[Effect of Liuwei Dihuang pill on expression of NF-kappaB in kidney lesion induced by gentamicin in rats].

OBJECTIVE: To study the effect of Liuwei Dihuang Pill on kidney lesion in rats induced by gentamicin and its mechanism. METHODS: Rats were divided into three groups: control group, gentamicin group, Liuwei Dihuang Pill group randomly. Parameters of kidney function and oxidative production in three groups were tested by biochemical analysis. Nuclear Factor-kappaB (NF-kappaB) protein were determined by western blotting. RESULTS: Parameters of weight, kidney indexes, oxidative production MDA and enzyme activity of NOS in kidney cortex of gentamicin group significantly increased (P < 0.05), and enzyme activity of SOD significantly decreased (P < 0. 05). The protein expression of NF-kappaB in gentamicin group was significantly up-regulated. After treatment with Liuwei Dihuang Pill, the above-mentioned up-regulated parameters were all significantly inhibited. CONCLUSION: Liuwei Dihuang Pill can inhibit the expression of NF-kappaB protein, so as to alleviate the renal oxidative lesion, and it may be one of the important mechanisms for treating gentamicin induced kidney lesion.

[Effect of jinfu kang to experimental precancerous colon lesions and urinary metabolites in rat].

OBJECTIVE: : To profile urinary metabolite variations from 1, 2-dimethylhydrazine (DMH)-induced precancerous colon rats, Jinfu Kang treated rats and healthy controls. METHOD: We used ethyl chloroformate derivatization and gas chromatography-mass spectrometry (GC-MS) based metabonomic method to analyze rat urines. RESULT: The time-dependent variations of metabolite profile showed a progressive deviation of the metabolism in the model group from the initial pattern over time and a systemic recovery of the metabolism in the treatment group, which is consistent with the histological results. The in-depth analysis indicated that the disorder of tricarboxylic acid cycle (TCA), tryptophan metabolism, polyamine metabolism and gut flora structure were associated with DMH intervention. CONCLUSION: Metabolic study revealed that Jinfu Kang can effectively reverse metabolic departures in DMH-induced precancerous colon rat, which is consistent with pathological results.

Tapetum degeneration retardation is critical for aliphatic metabolism and gene regulation during rice pollen development.

As a complex wall system in flowering plants, the pollen outer wall mainly contains aliphatic sporopollenin; however, the mechanism for synthesizing these lipidic precursors during pollen development remains less well understood. Here, we report on the function of the rice tapetum-expressing TDR (Tapetum Degeneration Retardation) gene in aliphatic metabolism and its regulatory role during rice pollen development. The observations of transmission electron microscopy (TEM) and scanning electron microscopy (SEM) analyses suggested that pollen wall formation was significantly altered in the tdr mutant. The contents of aliphatic compositions of anther were greatly changed in the tdr mutant revealed by GC-MS (gas chromatography-mass spectrometry) testing, particularly less accumulated in fatty acids, primary alcohols, alkanes and alkenes, and an abnormal increase in secondary alcohols with carbon lengths from C29 to C35 in tdr. Microarray data revealed that a group of genes putatively involved in lipid transport and metabolism were significantly altered in the tdr mutant, indicating the critical role of TDR in the formation of the pollen wall. Also, a wide range of genes (236 in total-154 up-regulated and 82 down-regulated) exhibited statistically significant expressional differences between wild-type and tdr. In addition to its function in promoting tapetum PCD, TDR possibly plays crucial regulatory roles in several basic biological processes during rice pollen development.

[Effect of Kangxianling Decoction on expression of hepatocyte growth factor mRNA and phosphorylations of extracellular signal-regulated protein kinase 1/2 and p38 in renal tissue of rats with unilateral ureteral obstruction].

OBJECTIVE: To study the effect of Kangxianling Decoction (KXLD), a compound traditional Chinese herbal medicine, on expression of hepatocyte growth factor (HGF) mRNA and phosphorylations of extracellular signal-regulated protein kinase 1/2 (ERK 1/2) and p38 in renal tissue of rats with unilateral ureteral obstruction (UUO). METHODS: Eighteen male SD rats were randomly divided into 3 groups: sham-operated group, untreated group and KXLD-treated group. A rat model of renal interstitial fibrosis was established by UUO. Rats with UUO were sacrificed after intragastric administration of KXLD for 14 days, and the parameters such as serum creatinine (SCr), blood urea nitrogen (BUN) and hydroxyproline in the kidney of rats in 3 groups were analyzed. The expression of HGF mRNA in kidney tissue was determined by reverse transcription polymerase chain reaction. The expressions of c-Met protein, ERK1/2 protein, p38 protein and the phosphorylations of ERK1/2 and p38 were determined by Western blotting method. RESULTS: The levels of SCr, BUN and hydroxyproline in the untreated group were significantly increased as compared with those in the sham-operated group (P<0.05). The expression of HGF mRNA in the untreated group was significantly down-regulated. The expression of c-Met protein and the phosphorylations of ERK1/2 and p38 in the kidney tissue of rats with UUO in the untreated group were significantly up-regulated. After intervention with KXLD, the phosphorylations of ERK1/2 and p38 were all significantly inhibited except for c-Met expression. The HGF mRNA was increased in KXLD-treated group. CONCLUSION: KXLD can decrease the level of collagen in the obstructed kidney of rats with UUO and alleviate the renal interstitial fibrosis in rats with UUO through enhancing the HGF mRNA expression and inhibiting the phosphorylations of ERK1/2 and p38.

[Experimental study on effect of Kangxianling on rat renal interstitial fibrosis].

OBJECTIVE: To study the effect and mechanism of Kangxianling (KXL, a TCM herbal compound) on renal interstitial fibrosis induced by unilateral ureteral obstruction (UUO). METHODS: Eighteen male SD rats were randomly divided into 3 groups, 6 in each group, the sham operated group, the model group, and the KXL group. Renal interstitial fibrosis model was established in rats by UUO. After rats were raised for additional 14 days, their body weight, serum levels of creatinine (SCr) and blood urea nitrogen (BUN) were analyzed. Then rats were sacrificed, their renal pathology examined by HE staining and PASM staining; expressions of transforming growth factor-beta1 (TGF-beta1), hepatocyte growth factor (HGF) mRNA, and a-smooth muscle actin (alpha-SMA), TGF-beta1 receptor I (TbetaR I), TGF-beta1 receptor II (TbetaR II) and hepatocyte growth factor receptor (C-Met) protein in kidney tissue were determined by RT-PCR and Western blotting respectively. RESULTS: SCr and BUN in the model group were significantly higher than those in the sham operated group (P <0.05). Expressions of TGF-beta1 mRNA and a-SMA, TbetaR I , TbetaR II and C-Met protein in kidney tissue in the model group significantly up-regulated and mRNA expression of HGF significantly down-regulated, and obvious hyperplasia of the base member of glomeruli was seen. After intervention with KXL, BUN content significantly lowered, alpha-SMA, TbetaR I and TbetaR II protein expression decreased and HGF mRNA expression up-regulated significantly in the treated group, with slight pathological changes only shown as mild hyperplasia of the base member of glomeruli and renal tubules. CONCLUSION: KXL could inhibit the protein expressions of a-SMA, TbetaR I , TbetaR II and increase the mRNA expression of HGF, which is a protective factor against renal fibrosis. Therefore, it is effective in alleviating the renal interstitial fibrosis and improving the renal function in UUO rats.

Analysis of dencichine in Panax notoginseng by gas chromatography-mass spectrometry with ethyl chloroformate derivatization.

Dencichine (beta-N-oxalyl-l-alpha,beta-diaminopropionic acid) is a haemostatic agent present in well-known traditional Chinese medicinal herbs such as Panax notoginseng, as well as other Panax species. It is also a reported neurotoxic agent found in Lathyrus sativus (grass pea seed) and cycad seeds. A method was developed for quantitative determination of the non-protein amino acid, dencichine, in plant samples of P. notoginseng and the adventitious roots directly from the explants of P. notoginseng after derivatization with ethyl chloroformate (ECF) by gas chromatography-mass spectrometry (GC-MS). l-2-chlorophenylalanine was used as an internal standard. Calibration curves were linear (r(2)=0.9988, n=6) in the range of 10-800 microg/ml for dencichine. Limit of detection and quantification for dencichine were 0.5 microg/ml and 2 microg/ml, respectively. This rapid and specific method may be applied to the quantification of dencichine in complex medicinal plants and their products.

[Observation on clinical effect of Angelica injection in treating acute cerebral infarction].

OBJECTIVE: To study the therapeutic effect of Angelica Injection (AI) in treating acute cerebral infarction (ACI). METHODS: One thousand four hundred and four patients, who were treated with AI (692 patients in Group A), compound salvia (390 patients in Group B) and low molecular dextran injection (322 patients in Group C) respectively. Indexes such as CT scanning on infarcted volume, scoring of clinical neuro-function deficit taking on the 1st, 3rd, 7th, 15th and 25th day, clinical therapeutic effectiveness evaluated by the end of the 2nd week and the improvement of Barthel index scores were observed. RESULTS: The total effective rate in Group A, B and C was 78.7%, 63.6% and 59.3% respectively, that in Group A was significantly higher than in the other two groups (P < 0.05). The improvement of neuro-function deficit scores and Barthel scores in Group A were better than those in Group B and C (on the 25th day, P < 0.01), and the decrement of infarcted volume in Group A was larger than that in Group C (P < 0.01). CONCLUSION: AI has evident therapeutic effect in treating ACI.