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1.
Nat Commun ; 11(1): 2249, 2020 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-32382010

RESUMO

Plant metacaspases mediate programmed cell death in development, biotic and abiotic stresses, damage-induced immune response, and resistance to pathogen attack. Most metacaspases require Ca2+ for their activation and substrate processing. However, the Ca2+-dependent activation mechanism remains elusive. Here we report the crystal structures of Metacaspase 4 from Arabidopsis thaliana (AtMC4) that modulates Ca2+-dependent, damage-induced plant immune defense. The AtMC4 structure exhibits an inhibitory conformation in which a large linker domain blocks activation and substrate access. In addition, the side chain of Lys225 in the linker domain blocks the active site by sitting directly between two catalytic residues. We show that the activation of AtMC4 and cleavage of its physiological substrate involve multiple cleavages in the linker domain upon activation by Ca2+. Our analysis provides insight into the Ca2+-dependent activation of AtMC4 and lays the basis for tuning its activity in response to stresses for engineering of more sustainable crops for food and biofuels.

2.
Diagn Cytopathol ; 2020 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-32374950

RESUMO

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare and aggressive hematologic malignancy arising from plasmacytoid dendritic cell precursors. The disease typically manifests in the skin, but it also evolves into a leukemic phase or can be complicated by other myeloid malignancies, especially myelomonocytic tumors. The association between these neoplasms is not fully elucidated. We report a case of BPDCN with a history of cytopenia that was supposed to be chronic myelomonocytic leukemia. The patient received intensive chemotherapy and achieved complete remission, but soon relapsed. The successive occurrence of myelomonocytic neoplasm and BPDCN is in accordance with the fact that they evolve from a common cell origin with a multilineage potential for myelomonocytic and plasmacytoid dendritic cell differentiation. This case may shed further light on the mystery of biology and the histogenesis of BPDCN.

3.
BMC Immunol ; 21(1): 23, 2020 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-32349664

RESUMO

BACKGROUND: CD8+CD28- T suppressor (Ts) cells play critical role in transplant tolerance. Our previous study has generated CD8+CD28- Ts cells in vitro which exert robust allospecific suppressive capacity in vitro. RESULTS: CD8+CD28- Ts cells were expanded by stimulating human CD8+ T cells with allogeneic antigen presenting cells in the presence of the common gamma chain cytokines IL-2, IL-7 and IL-15 in vitro, and were further verified in vitro through day 7 to 11 for their persistency of the allospecific suppressive capacity. When CD8+CD28- Ts cells were adoptively transferred into NOG mice, their capacity to inhibit CD4+ T cell proliferation in allospecific manner remained potent on 11 days after their injection. The mechanisms for expansion of CD8+CD28- Ts cells by the common gamma chain cytokines were investigated. These included promoting CD8+CD28- T cells proliferation, converting CD8+CD28+ T cells to CD8+CD28- T cells and decreasing CD8+CD28- T cell death. Furthermore, the expanded CD8+CD28- Ts cells showed upregulation of the co-inhibitory molecule Tim-3 and down-regulation of the cytotoxic molecule granzyme B. CONCLUSIONS: In summary, these results demonstrated that the in vitro-expanded human CD8+CD28- T cells retained potent allospecific suppressive capacity in vivo and depicted multiple mechanisms for the expansion of Ts cells, which might promote further bench to clinic research.

4.
Nat Commun ; 11(1): 2089, 2020 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-32350277

RESUMO

The role of dysregulation of mRNA alternative splicing (AS) in the development and progression of solid tumors remains to be defined. Here we describe the first comprehensive AS landscape in the spectrum of human prostate cancer (PCa) evolution. We find that the severity of splicing dysregulation correlates with disease progression and establish intron retention as a hallmark of PCa stemness and aggressiveness. Systematic interrogation of 274 splicing-regulatory genes (SRGs) uncovers prevalent genomic copy number variations (CNVs), leading to mis-expression of ~68% of SRGs during PCa development and progression. Consequently, many SRGs are prognostic. Surprisingly, androgen receptor controls a splicing program distinct from its transcriptional regulation. The spliceosome modulator, E7107, reverses cancer aggressiveness and inhibits castration-resistant PCa (CRPC) in xenograft and autochthonous PCa models. Altogether, our studies establish aberrant AS landscape caused by dysregulated SRGs as a hallmark of PCa aggressiveness and the spliceosome as a therapeutic vulnerability for CRPC.

5.
Nat Cell Biol ; 2020 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-32367048

RESUMO

How transplanted haematopoietic stem cells (HSCs) behave soon after they reside in a preconditioned host has not been studied due to technical limitations. Here, using single-cell RNA sequencing, we first obtained the transcriptome-based classifications of 28 haematopoietic cell types. We then applied them in conjunction with functional assays to track the dynamic changes of immunophenotypically purified HSCs in irradiated recipients within the first week after transplantation. Based on our transcriptional classifications, most homed HSCs in bone marrow and spleen became multipotent progenitors and, occasionally, some HSCs gave rise to megakaryocytic-erythroid or myeloid precursors. Parallel in vitro and in vivo functional experiments supported the paradigm of robust differentiation without substantial HSC expansion during the first week. Therefore, this study uncovers the previously inaccessible kinetics and fate choices of transplanted HSCs in myeloablated recipients at early stage, with implications for clinical applications of HSCs and other stem cells.

6.
Biotechnol J ; : e1900424, 2020 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-32271998

RESUMO

In recent decades, fast advancements in the fields of metal-organic frameworks (MOFs) are providing unprecedented opportunities for the development of novel functional MOFs for various biosensing applications. Exciting progress is achieved due to the combination of MOFs with various functional components, which introduces novel structures and new features to the MOFs-based biosensing applications, such as higher stability, higher sensitivity, higher flexibility, and higher specificity. This review aims to be a comprehensive summary of the most recent advances in the development of functional MOFs for various biosensing applications, placing special attention on important contributions in recent 3 years. In this review, the most recent developments in design and synthesis of functional MOFs for biosensing applications are summarized. MOFs-based biosensing applications are outlined according to the central roles of MOFs in biosensors, which include carriers of sensitive elements, enzyme-mimic elements, electrochemical signaling, optical signaling, and gas sensing. Finally, the current challenges and future development trends of functional MOFs for biosensing applications are proposed and discussed.

7.
World Neurosurg ; 2020 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-32298823

RESUMO

OBJECTIVE: Despite the increasing evidence of the association between breast cancer and meningioma in women, the relationship between these tumors remains improperly examined. In this study, we aim to identify the sociodemographic and clinicopathologic features of women with breast cancer associated with a higher risk of developing a meningioma. METHODS: The SEER (Surveillance Epidemiology and End Results) database (18 registries) was used to identify women with breast cancer as their first neoplasm. The risk of subsequent meningioma was reported as the standardized incidence ratio (SIR) and was analyzed by sociodemographic and clinicopathologic subgroups. Results are given as SIR (95% confidence interval [CI]). RESULTS: A total of 564,516 women diagnosed with breast cancer between 2004 and 2016 were included for analysis. A 26% increased risk of meningioma development (SIR, 1.26; 95% CI, 1.19-1.33; P < 0.05) was found in the cohort compared with the general population. Patients aged between 18 and 49 years (SIR, 2.16; 95% CI, 1.78-2.61; P < 0.05) and those with a more advanced tumor stage (stage IV; SIR, 2.39; 95% CI, 1.71-3.25; P < 0.05) were at a higher risk. Hormone receptor expression and treatment modality subgroups were at a similar risk compared with the general population. CONCLUSIONS: Our study corroborated the known association between these tumors and found a 26% risk of meningioma development in women with breast cancer, with younger patients and those with a more aggressive disease having a higher than expected risk.

9.
Carbohydr Polym ; 237: 116173, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32241447

RESUMO

In this study, a fully bio-based coating was constructed by layer-by-layer deposition of chitosan (CS) and ammonium phytate (AP), to obtain fire-safety and antibacterial cotton fabrics. With about 8% weight gains of CS/AP coatings, the treated cotton fabrics self-extinguished in the vertical burning test. The data obtained from cone calorimetry showed CS/AP/cotton had much lower smoke and heat production, which indicated the fire safety of the fabrics was significantly improved for the presence of CS/AP coatings. The flame-retardant mechanism of this system was finally proposed according to the analysis of gaseous products and char residues. What is more, CS/AP coatings had higher antibacterial activity in Gram-negative bacteria and did improve the tensile strength of cotton fabrics compared with AP coating. With its ease of operation and use of non-toxic chemicals, this fully bio-based coating can further offer a feasible flame-retardant and antibacterial solution of the inflammable natural fabrics.

10.
Oxid Med Cell Longev ; 2020: 2172740, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32256947

RESUMO

Nature is a vast source of bioactive molecules and has provided an active and efficient reservoir for drug discovery. Among natural compounds, one of the most promising is Schisandrin B (Sch B), isolated from Schisandra chinensis, which was documented to possess diversified pharmacokinetic propriety, among them antioxidant, anti-inflammation, cardioprotection, and neuroprotection. Due to its large biological properties, Sch B was recorded to be a potent cure for several diseases by targeting several signaling pathways. This review is aimed at emphasizing the recent data on the biological properties of Sch B among the molecular mechanism of this drug on tumoral, cardiac, and neural diseases. The data suggest that the antitumor activities of Sch B were mainly through apoptosis and cell cycle arrest at the diver's stage. It is reported that Sch B could be used as effective chemotherapy, neuroprotection, and cardioprotection since it possesses a spectrum of biological activities; however, further investigations on the mechanism of its action and preclinical trials are still mandatory to further validate the potential of this natural drug candidate.

11.
J Biol Chem ; 295(20): 7003-7017, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32273342

RESUMO

Cholelithiasis is one of the most prevalent gastroenterological diseases and is characterized by the formation of gallstones in the gallbladder. Both clinical and preclinical data indicate that obesity, along with comorbidity insulin resistance, is a predisposing factor for cholelithiasis. Forkhead box O1 (FoxO1) is a key transcription factor that integrates insulin signaling with hepatic metabolism and becomes deregulated in the insulin-resistant liver, contributing to dyslipidemia in obesity. To gain mechanistic insights into how insulin resistance is linked to cholelithiasis, here we determined FoxO1's role in bile acid homeostasis and its contribution to cholelithiasis. We hypothesized that hepatic FoxO1 deregulation links insulin resistance to impaired bile acid metabolism and cholelithiasis. To address this hypothesis, we used the FoxO1LoxP/LoxP-Albumin-Cre system to generate liver-specific FoxO1-knockout mice. FoxO1-knockout mice and age- and sex-matched WT littermates were fed a lithogenic diet, and bile acid metabolism and gallstone formation were assessed in these animals. We showed that FoxO1 affected bile acid homeostasis by regulating hepatic expression of key enzymes in bile acid synthesis and in biliary cholesterol and phospholipid secretion. Furthermore, FoxO1 inhibited hepatic expression of the bile acid receptor farnesoid X receptor and thereby counteracted hepatic farnesoid X receptor signaling. Nonetheless, hepatic FoxO1 depletion neither affected the onset of gallstone disease nor impacted the disease progression, as FoxO1-knockout and control mice of both sexes had similar gallstone weights and incidence rates. These results argue against the notion that FoxO1 is a link between insulin resistance and cholelithiasis.

12.
J Mater Chem B ; 2020 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-32314756

RESUMO

Recently, with increasing medical practices, including organ transplantation and tumor chemotherapy, fungal infections, particularly the occurrence of drug-resistant fungal strains, remain a severe problem for the public health, which cause worse complications in the immunocompromised patients. The search for efficacious yet safe antifungal agents is in high demand in precision medicine. However, fungicides are often poorly water soluble for oral absorption, which is difficult for pharmaceutical efficacy evaluation. In this study, lipophilic oleic acid (OA)-grafted mesoporous silica (SBA-15) was facilely modified by cetyltrimethylammonium bromide (CTAB), which acts as an efficient antifungal drug matrix of itraconazole (ITZ). Characterized by physicochemical methods, the rod-like SBA-15-OA-CTAB/ITZ composite with retained mesostructural regularity shows that the loading amount of ITZ in the mesopore is ∼18%, contributing to the enhanced antifungal activity against Aspergillus fumigatus (A. fumigatus) and Candida albicans (C. albicans). The antimicrobial mechanism study suggests that the reactive oxygen species (ROS) were formed when fungal cells were incubated with the formulated ITZ, while there was no ROS formation in the presence of pure ITZ, which may result from the quaternary ammonium moieties of CTAB in the nanocomposites. Due to the potential toxicity of CTAB on mammalian cells, the as-synthesized mesoporous SBA-15-OA-CTAB/ITZ provides an alternative molecular design for the formulation improvement of a lipophilic antifungal drug applicable for external uses such as topical therapy.

13.
Artigo em Inglês | MEDLINE | ID: mdl-32326110

RESUMO

The improper stacking of chromium (Cr) slag poses a great threat to the environment and human health. The toxicity of Cr in soil is not only related to its total amount, but also to its fractions. A simulated experiment was conducted in laboratory to assess the environmental risk of Cr fractions migration and distribution in red soil. The results showed the content of acid-soluble and reducible Cr significantly decreased (P < 0.05) in top layer but increased in middle and substratum layers over time. This indicated that acid-soluble and reducible Cr migrated downward with time and the relative mobility of acid-soluble Cr (0.038 mg/kg·d·m) was higher than that of reducible Cr (0.028 mg/kg·d·m). Furthermore, correlation analysis between microbial community and chromium fraction showed the relative abundance of Lysobacter, Flavihumibacter, Flavisolbacter, and Altererythrobacter was significantly (P < 0.05) correlated with acid-soluble and reducible fractions. Thus, these microorganisms might be evaluators to assess the migration of acid-soluble and reducible fractions in red soil. In summary, this study provided a new comprehension on remediation of Cr-contaminated soil by monitoring the migration of acid-soluble and reducible fractions and the changes of related microbial groups.

14.
Nat Nanotechnol ; 15(5): 406-416, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32123380

RESUMO

Chronic hepatitis B is caused by prolonged infection with the hepatitis B virus (HBV), which can substantially increase the risk of developing liver disease. Despite the development of preventive vaccines against HBV, a therapeutic vaccine inducing an effective antibody response still remains elusive. The preS1 domain of the large HBV surface protein is the major viral attachment site on hepatocytes and thus offers a therapeutic target; however, its poor immunogenicity limits clinical translation. Here, we design a ferritin nanoparticle vaccine that can deliver preS1 to specific myeloid cells, including SIGNR1+ dendritic cells (which activate T follicular helper cells) and lymphatic sinus-associated SIGNR1+ macrophages (which can activate B cells). This nanoparticle vaccine induces a high-level and persistent anti-preS1 response that results in efficient viral clearance and partial serological conversion in a chronic HBV mouse model, offering a promising translatable vaccination strategy for the functional cure of chronic hepatitis B.

15.
Am J Physiol Endocrinol Metab ; 318(5): E791-E805, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32182124

RESUMO

Irisin, a newly identified myokine, is critical to modulating body metabolism and biological homeostasis. However, whether irisin protects the skeletal muscles against metabolic stresses remains unknown. In this study, we determine the effect of irisin on high glucose and fatty acid-induced damages using irisin-overexpressed mouse C2C12 (irisin-C2C12) myoblasts and skeletal muscle from irisin-injected mice. Compared with empty vector-transfected control C2C12 cells, irisin overexpression resulted in a marked increase in cell viability and decrease in apoptosis under high-glucose stress. Progression of the cell cycle into the G2/M phase in the proliferative condition was also observed with irisin overexpression. Furthermore, glucose uptake, glycogen accumulation, and phosphorylation of AMPKα/insulin receptor (IR) ß-subunit/Erk1/2 in response to insulin stimulation were enhanced by irisin overexpression. In irisin-C2C12 myoblasts, these responses of phosphorylation were preserved under palmitate treatment, which induced insulin resistance in the control cells. These effects of irisin were reversed by inhibiting AMPK with compound C. In addition, high glucose-induced suppression of the mitochondrial membrane potential was also prevented by irisin. Moreover, suppression of IR in irisin-C2C12 myoblasts by cotransfection of shRNA against IR also mitigated the effects of irisin while not affecting AMPKα phosphorylation. As an in vivo study, soleus muscles from irisin-injected mice showed elevated phosphorylation of AMPKα and Erk1/2 and glycogen contents. Our results indicate that irisin counteracts the stresses generated by high glucose and fatty acid levels and irisin overexpression serves as a novel approach to elicit cellular protection. Furthermore, AMPK activation is a crucial factor that regulates insulin action as a downstream target.

17.
Biomed Pharmacother ; 125: 109982, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32119646

RESUMO

BACKGROUND: Colorectal cancer (CRC) has a high incidence and mortality rate worldwide. Colitis-associated CRC (CAC) is used for describing the relationship between inflammation and CRC. No chemopreventive agents have been found to be both effective and safe in CRC. Therefore, the prevention and treatment of CAC are extremely urgent. Wu Mei Wan (WMW) has been used for the clinical treatment of enteritis with a remarkable efficacy. Here, we aim to investigate the underlying mechanism of WMW in the prevention of CAC. METHODS: The AOM/DSS-induced CAC mouse model was used, and the mice were divided into normal control (NC), AOM/DSS model control (MC), and AOM/DSS plus WMW (WMW). The weight of mice, the score of DAI, survival rate, number of tumors and sample collection were performed at the end of the 14th week. Histopathological examination was performed using Hematoxylin-Eosin (HE) staining. Tumor cell proliferation was indicated by the expression of PCNA, and p65 and p-STAT3 were detected by immunohistochemistry. Serum IL-6 levels were detected by enzyme-linked immunosorbent assay (ELISA). The expression of p65, IL-6 and p-STAT3 in the colon was detected by Western Blot. Intestinal flora was analyzed by 16S rDNA sequencing. RESULTS: WMW improved the survival rate of mice in the MC group and also attenuated CAC symptoms such as abnormal clinical colitis and pathological changes to intestinal tissue by reducing DAI score, tumor formation, tumor volume, and grade of tumorigenesis. WMW also reduced the proliferation of tumor cells in colon tissues. WMW decreased the expression of p65, IL-6, and p-STAT3 in colon tumors of CAC mice. WMW decreased Bacteroidetes and increased Firmicutes at the phylum level, while decreasing bacteroidales_s24-7_group and increasing the number of Lachnospiraceae at the family level. CONCLUSION: WMW attenuates CAC by regulating the balance between "tumor-promoting bacteria" and "tumor-suppressing bacteria" and the NF-kB/IL-6/STAT3 pathway. WMW has the potential to be a safe and effective chemopreventive drug but further clinical evidence is necessary.

18.
Chin J Nat Med ; 18(2): 90-102, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32172952

RESUMO

With the occurrence of aging process, decreased neuron dopamine, disrupted brown adipose tissue (BAT) remodeling and decreased butyrate level all reflect a weak host healthy in certain degree. Nevertheless, the signs of mid-adult gut microbiota, and its association with host healthy are not well understood. In current study, we deemed to illustrate the associations of age, neuron dopamine, BAT remodeling, butyrate and gut microbiota with the aid of traditional herbal formula Kang Shuai Lao Pian (KSLP), which is known for its anti-aging effect. Here, ELISA was performed to detect the production of brain dopamine, the mass of inguinal white adipose tissue versus interscapular brown adipose tissue (iWAT/iBAT) was calculated and considered as a sign of BAT remodeling, 16S rRNA gene sequencing was used to the detection of gut microbiota profiling and gas chromatography was used to measure the butyrate level in mice feces. Our results indicated mid-adult mice already present distinctive gut microbiota profiling compared with young mice, concomitant with which are the lower brain dopamine level and disrupted brown adipose remodeling. KSLP treatment improved the host healthy and regulated gut microbiota with enriched Firmicutes at the expense of Bacteroidetes, particularly increased the relative abundance of bacteria functionally related to dopamine and butyrate productions, which suggest KSLP treatment constructs a healthier gut environment. In conclusion, modulation of gut microbiota and butyrate may connectively regulate dopamine production and BAT remodeling through gut-brain axis and gut-metabolism axis.

19.
PLoS Biol ; 18(3): e3000654, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32134919

RESUMO

Proteasomes are highly abundant and conserved protease complexes that eliminate unwanted proteins in the cells. As a single-chain ATP-independent nuclear proteasome activator, proteasome activator 200 (PA200) associates with 20S core particle to form proteasome complex that catalyzes polyubiquitin-independent degradation of acetylated histones, thus playing a pivotal role in DNA repair and spermatogenesis. Here, we present cryo-electron microscopy (cryo-EM) structures of the human PA200-20S complex and PA200 at 2.72 Å and 3.75 Å, respectively. PA200 exhibits a dome-like architecture that caps 20S and uses its C-terminal YYA (Tyr-Tyr-Ala) to induce the α-ring rearrangements and partial opening of the 20S gate. Our structural data also indicate that PA200 has two openings formed by numerous positively charged residues that respectively bind (5,6)-bisdiphosphoinositol tetrakisphosphate (5,6[PP]2-InsP4) and inositol hexakisphosphate (InsP6) and are likely to be the gates that lead unfolded proteins through PA200 and into the 20S. Besides, our structural analysis of PA200 found that the bromodomain (BRD)-like (BRDL) domain of PA200 shows considerable sequence variation in comparison to other human BRDs, as it contains only 82 residues because of a short ZA loop, and cannot be classified into any of the eight typical human BRD families. Taken together, the results obtained from this study provide important insights into human PA200-induced 20S gate opening for substrate degradation and the opportunities to explore the mechanism for its recognition of H4 histone in acetylation-mediated proteasomal degradation.

20.
PLoS One ; 15(3): e0230178, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32187213

RESUMO

The Olsen phosphorus (Olsen-P) concentration of soil is generally a good indicator for estimating the bioavailability of P and environmental risk in soils. To maintain soil Olsen-P at adequate levels for crop growth and environmental sustainability, the relationship between soil Olsen-P and the P budget (the P input minus the output) as well as the variations of soil Olsen-P and P budget were investigated from three long-term (22 years) experiments in China. Five treatments were selected: (1) unfertilized control (CK); (2) nitrogen and potassium (NK); (3) nitrogen, phosphorous, and potassium (NPK); (4) nitrogen, phosphorous, potassium and straw; (5) nitrogen, phosphorous, potassium and manure. The results showed that without P fertilizers (CK, NK), there was a soil P deficit of 75-640 kg ha-1, and the lowest P deficit (mean of CK and NK) was in Eutric Cambisol. Soil Olsen-P decreased by 0.11-0.39 mg kg-1 year-1 in the order of Luvic Phaeozems > Eutric Cambisol > Calcaric Cambisol. Soil Olsen-P and the P deficit had a significantly (P<0.01) positive linear relationship. For every 100 kg of P ha-1 of deficit, soil Olsen-P decreased by 0.44-9.19 mg kg-1 in the order of Eutric Cambisol > Luvic Phaeozems > Calcaric Cambisol. Under the P fertilizer treatments (NPK, NPKS, and NPKM), soil Olsen-P showed an obvious surplus (except the NPK and NPKS in Luvic Phaeozems) of 122-2190 kg ha-1, and the largest P surplus was found under the NPKM treatment at each site. The relation between soil Olsen-P and the experimental years could be simulated using quadratic equation of one unknown in Calcaric Cambisol for the lower P input after 14 years of fertilization. And soil Olsen-P increased by 1.30-7.69 mg kg-1 year-1 in the order of Luvic Phaeozems > Eutric Cambisol. The relation between soil Olsen-P and the P surplus could be simulated by a simple linear equation except under NPK and NPKS in Luvic Phaeozems. With 100 kg ha-1 P surplus, soil Olsen-P increased by 3.24-7.27 mg kg-1 in the order of Calcaric Cambisol (6.42 mg kg-1) > Eutric Cambisol (3.24 mg kg-1). In addition, the change in soil Olsen-P with a 100 kg P ha-1 surplus (soil Olsen-P efficiency) was affected by the soil organic matter (SOM), pH, and CaCO3 content, etc. In the practice of fertilization, it's not necessary to increase the amount of P fertilizers, farmers should take measure to solve the local problem, for adjust the soil pH of Eutric Cambisol and Calcaric Cambisol, and apply more nitrogen in Luvic Phaeozems. In the area of serious soil P surplus, it is encouraged to stop applying P fertilizers for a few years to take advantage of soil accumulated P and make the high Olsen-P content decrease to a reasonable level.

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