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1.
Int J Cancer ; 2024 Jul 08.
Article in English | MEDLINE | ID: mdl-38973577

ABSTRACT

The long-term incidence trends of 32 cancers in China remained unclear. Cancer statistics for young population were often presented in aggregate, masking important heterogeneity. We aimed to assess the incidence trends of 32 cancers in China from 1983 to 2032, stratified by sex and age groups. Data on cancer incidence from 1983 to 2017 were extracted from Cancer Incidence in Five Continents Volumes VI-XII. The age-period-cohort model was utilized to assess age and birth cohort effects on the temporal trends of 32 cancers in China, while the Bayesian age-period-cohort model was utilized to project future trends from 2018 to 2032. An increase in cohort effects is observed in some cancers such as thyroid and kidney cancers. Eight of the 12 obesity-related cancers may rise in the 0-14 age group, and nine in the 15-39 age group from 2013 to 2032. Liver and stomach cancers show an increasing trend among the younger population, contrasting with the observed declining trend in the middle-aged population. There has been a significant rise in the proportions of cervical cancer among females aged 40-64 (4.3%-19.1%), and prostate cancer among males aged 65+ (1.1%-11.8%) from 1983 to 2032. Cancer spectrum in China is shifting toward that in developed countries. Incidence rates of most cancers across different age groups may increase in recent cohorts. It is essential to insist effective preventive interventions, and promote healthier lifestyles, such as reducing obesity, especially among younger population.

2.
Chin Med J (Engl) ; 2024 Apr 26.
Article in English | MEDLINE | ID: mdl-38679485

ABSTRACT

BACKGROUND: Poly adenosine-diphosphate-ribose polymerase (PARP) inhibitors (PARPi) have been approved to act as first-line maintenance (FL-M) therapy and as platinum-sensitive recurrent maintenance (PSR-M) therapy for ovarian cancer in China for >5 years. Herein, we have analyzed the clinical-application characteristics of olaparib and niraparib in ovarian cancer-maintenance therapy in a real-world setting to strengthen our understanding and promote their rational usage. METHODS: A retrospective chart review identified patients with newly diagnosed or platinum-sensitive recurrent ovarian cancer, who received olaparib or niraparib as maintenance therapy at Sichuan Cancer Hospital between August 1, 2018, and December 31, 2021. Patient medical records were reviewed. We grouped and analyzed patients based on the type of PARPi they used (the olaparib group and the niraparib group) and the line of PARPi maintenance therapy (the FL-M setting and the PSR-M setting). The primary endpoint was the 24-month progression-free survival (PFS) rate. RESULTS: In total, 131 patients (olaparib: n = 67, 51.1%; niraparib: n = 64, 48.9%) were enrolled. Breast cancer susceptibility genes (BRCA) mutations (BRCAm) were significantly less common in the niraparib group than in the olaparib group [9.4% (6/64) vs. 62.7% (42/67), P <0.001], especially in the FL-M setting [10.4% (5/48) vs. 91.4% (32/35), P <0.001]. The 24-month PFS rates in the FL-M and PSR-M settings were 60.4% and 45.7%, respectively. In patients with BRCAm, the 24-month PFS rates in the FL-M and PSR-M settings were 62.2% and 72.7%, respectively. CONCLUSIONS: Olaparib and niraparib were effective in patients with ovarian cancer without any new safety signals except for skin pigmentation. In patients with BRCAm, the 24-month PFS of the PARPi used in the PSR-M setting was even higher than that used in the FL-M setting.

3.
Front Cell Infect Microbiol ; 14: 1361045, 2024.
Article in English | MEDLINE | ID: mdl-38572320

ABSTRACT

Introduction: Over the past decade, Corynebacterium striatum (C. striatum), an emerging multidrug-resistant (MDR) pathogen, has significantly challenged healthcare settings, especially those involving individuals with weakened immune systems. The rise of these superbugs necessitates innovative solutions. Methods: This study aimed to isolate and characterize bacteriophages targeting MDR-C. striatum. Utilizing 54 MDR-C. striatum isolates from a local hospital as target strains, samples were collected from restroom puddles for phage screening. Dot Plaque and Double-layer plate Assays were employed for screening. Results: A novel temperate bacteriophage, named CSP1, was identified through a series of procedures, including purification, genome extraction, sequencing, and one-step growth curves. CSP1 possesses a 39,752 base pair circular double-stranded DNA genome with HK97-like structural proteins and potential for site-specific recombination. It represents a new species within the unclassified Caudoviricetes class, as supported by transmission electron microscopy, genomic evolutionary analysis, and collinearity studies. Notably, CSP1 infected and lysed 21 clinical MDR-C. striatum isolates, demonstrating a wide host range. The phage remained stable in conditions ranging from -40 to 55°C, pH 4 to 12, and in 0.9% NaCl buffer, showing no cytotoxicity. Discussion: The identification of CSP1 as the first phage targeting clinical C. striatum strains opens new possibilities in bacteriophage therapy research, and the development of diagnostic and therapeutic tools against pathogenic bacteria.


Subject(s)
Bacteriophages , Corynebacterium Infections , Humans , Bacteriophages/genetics , Corynebacterium/genetics , Corynebacterium Infections/microbiology , Genomics , Anti-Bacterial Agents
4.
Int J Cancer ; 154(3): 465-476, 2024 Feb 01.
Article in English | MEDLINE | ID: mdl-37707172

ABSTRACT

China accounted for 45.3% of new cases of primary liver cancer (PLC) worldwide in 2020. While variations in PLC incidence between different regions of China and decreasing incidence in overall China have been reported, incidence patterns have not been thoroughly explored by region. We examined the nearly status and temporal trends of PLC incidence in different geographical regions in China and project future trends. The age-standardized incidence rate (ASR) was estimated for 1978 to 2012 by different geographical regions and gender in China. Age-period-cohort model was adopted to evaluate age and birth cohort effects on the temporal trend of five registries of China (Hong Kong, Shanghai, Jiashan, Harbin and Zhongshan), Bayesian age-period-cohort model was adopted to project future trends for 2013 to 2032. PLC incidence in China exhibits marked geographical disparity, with the highest incidence in Southwest China, and gender differences being particularly pronounced in South China. While other registries exhibited decreasing trend, Zhongshan exhibited an increasing trend, with the cohort effect showing a marked upward trend for females born in 1916 to 1949 and males born in 1916 to 1962. During 2013 to 2032, the ASR appears to increase by 86.9% for men and 40.0% for women in Zhongshan, while the remaining registries will decline by around 50%. Since the high incidence of hepatitis B virus infection in early birth cohort, recent rise of nonviral risk factors and the severe aging of the Chinese population, it may be critical to tailor future prevention and control strategies for PLC to the distribution of risk factors in different geographical regions.


Subject(s)
Liver Neoplasms , Male , Humans , Female , Aged, 80 and over , Incidence , China/epidemiology , Bayes Theorem , Cohort Studies , Registries , Liver Neoplasms/epidemiology
5.
J Nat Prod ; 87(1): 141-151, 2024 01 26.
Article in English | MEDLINE | ID: mdl-38128907

ABSTRACT

Twelve new austalide meroterpenoids (1-12) were isolated from the endophytic fungus Diaporthe sp. XC1211. Their structures were elucidated by extensive spectroscopic analysis. The absolute configurations of compounds 1, 3, 4, and 6 were established by single-crystal X-ray diffraction, whereas those for the others were established by experimental electronic circular dichroism (ECD) data analysis. Compounds 1-12 represent a rare class of austalides with a 24α-CH3. Compounds 2 and 5 demonstrated potent proliferation inhibitory effects against LPS-induced B cells with IC50 values of 6.7 (SI = 3.6) and 3.8 (SI > 13) µM, respectively. Compounds 2 and 5 decreased the secretion of IL-6 in LPS-induced B cells in a dose-dependent manner.


Subject(s)
Fungi , Lipopolysaccharides , Molecular Structure , Lipopolysaccharides/pharmacology , Crystallography, X-Ray , Circular Dichroism
6.
Bioorg Chem ; 139: 106745, 2023 10.
Article in English | MEDLINE | ID: mdl-37499531

ABSTRACT

Eight unreported andrastin-type meroterpenoids, namely peniandrastins A-H (1-8), along with six known analogues (9-14), were isolated from the fermentation of a soil-derived fungus Penicillium sp.sb62. Their structures with absolute configurations were elucidated by detailed analyses of the spectroscopic data and single-crystal X-ray diffraction. Compounds 1-4 belong to a rare class of 21-nor-andrastin meroterpenoids, of which 1 bears a 10-hydroperoxyl group, and 2 and 3 feature a 6/6/6/5/5 and a 6/6/6/5/6 pentacyclic systems, respectively. Compounds 5-8 are C25 andrastin-type meroterpenoids, wherein 5 features an unprecedented cyclopentan-1-keton-3-hemiacetal moiety. Additionally, the absolute configuration of compound 9 was corroborated by single-crystal X-ray crystallography for the first time. All isolates were evaluated for their immunosuppressive activities. As a result, compounds 1, 3, 4, 7-9 and 12-14 inhibited concanavalin A-induced T cell proliferation with IC50 values ranging from 7.49 to 36.52 µM, and 1-4, 6-9 and 12-14 inhibited lipopolysaccharide-induced B cell proliferation with IC50 values ranging from 6.73 to 26.27 µM. The preliminary structure-activity relationships (SARs) of those isolates were also discussed.


Subject(s)
Penicillium , Penicillium/chemistry , Molecular Structure , Spectrum Analysis , Fungi , Structure-Activity Relationship
7.
J Nat Prod ; 86(1): 66-75, 2023 01 27.
Article in English | MEDLINE | ID: mdl-36596229

ABSTRACT

Peniandranoids A-E (1-5), five new meroterpenoids, together with three known analogues (6-8), were isolated from the fermentation of a soil-derived fungus, Penicillium sp.sb62. Their structures including absolute configurations were determined by extensive spectroscopic analysis, and the absolute configurations of compounds 1 and 5 were further elucidated by single-crystal X-ray diffraction. Peniandranoids A-E belong to a rare class of andrastin-type meroterpenoids incorporating an extra polyketide unit (a C10 polyketide unit for 1 and 2, a C9 polyketide unit for 3 and 4, and a furancarboxylic acid unit for 5). Compounds 1 and 6 exhibited favorable inhibitory activities against influenza virus A (H1N1) with EC50 values of 19 and 14 µg/mL, respectively. Compounds 3-8 exhibited potent immunosuppressive activities against concanavalin A-induced T cell proliferation with EC50 values ranging from 4.3 to 27 µM and lipopolysaccharide-induced B cell proliferation with EC50 values ranging from 7.5 to 23 µM, respectively.


Subject(s)
Influenza A Virus, H1N1 Subtype , Penicillium , Polyketides , Molecular Structure , Penicillium/chemistry , Antiviral Agents/pharmacology , Antiviral Agents/chemistry
8.
Front Public Health ; 10: 1018084, 2022.
Article in English | MEDLINE | ID: mdl-36530668

ABSTRACT

Objective: Studies have shown that screening for pre-diabetes mellitus (pre-DM) is essential to prevent type 2 diabetes mellitus (T2DM). This study evaluates the cost-effectiveness of two screening strategies that apply the Chinese Diabetes Risk Score (CDRS) to screen for pre-DM in China. Methods: A Markov microsimulation model was conducted from a social perspective, and the input parameters were obtained from published literature or publicly available data. Two screening strategies for pre-DM based on CDRS were built and compared with the control group to determine the cost-effective strategy. The screening strategy of the control group was screening for pre-DM by fasting plasma glucose (FPG) test in adults undergoing annual health examination and no screening in adults without an annual health examination (status quo). Two screening strategies were strategy 1: screening for pre-DM using CDRS in all adults (including with or without an annual health examination); and strategy 2: supplemental self-screening for pre-DM using CDRS in adults without an annual health examination, based on the status quo. We focus on the cumulative prevalence of T2DM and the incremental cost-effectiveness ratio which signifies the cost per case of T2DM prevented. We also evaluated the cost-effectiveness from the health system perspective. One-way and probabilistic sensitivity analyses were conducted to verify the robustness of the results. Results: The costs a case of T2DM prevented for strategy 1 compared with the control group and strategy 2 were $299.67 (95% CI 298.88, 300.46) and $385.89 (95% CI 381.58, 390.20), respectively. In addition, compared with the control group, the cost of strategy 2 to prevent a case of T2DM was $272.23 (95% CI 271.50, 272.96). Conclusions: Screening for pre-DM using CDRS in all adults was the most cost-effective health policy. We suggest that medical institutions replace FPG with CDRS for pre-DM screening; at the same time, self-screening for pre-DM using CDRS is widely promoted among adults without an annual health examination. There were still some disputes about how CDRS is included in the health examination projects, so strategy 2 should be considered as an alternative screening strategy. Findings provide a reference for the application of the CDRS in pre-DM screening and contribute to T2DM prevention.


Subject(s)
Diabetes Mellitus, Type 2 , Prediabetic State , Adult , Humans , Prediabetic State/diagnosis , Diabetes Mellitus, Type 2/diagnosis , Diabetes Mellitus, Type 2/prevention & control , Cost-Benefit Analysis , East Asian People , Risk Factors , China/epidemiology
9.
Cancer Manag Res ; 14: 2609-2623, 2022.
Article in English | MEDLINE | ID: mdl-36072386

ABSTRACT

Purpose: tsRNA is a type of small non-coding RNA derived from tRNA. Diffuse gliomas are the most common brain tumors. This investigation focused on tsRNA identification and characterization within gliomas. Methods: The sequences of human tRNA and tsRNAs were taken from GtRNAdb, tRFdb and tRFexplorer databases. Data processing and bioinformatic analysis were performed with R or Python software. The expression of tsRNAs in glioma tissues was analyzed by qRT-PCR assay. Results: With computational approaches, we identified hundreds of tsRNAs with available expression abundance in the glioma datasets, most of them derived from the 3' end or 5' end of mature tRNA. Among the tsRNAs derived from tRNA-Leu-CAA, ts-26, tRFdb-3012a, and tRFdb-3012b (tRFdb-3012a/b) were significantly decreased in diffuse gliomas. The clinical survivals of glioma patients with low tsRNA (ts-26, tRFdb-3012a, and tRFdb-3012b) expression were remarkably worse than that of those with high expression. Expression of tRFdb-3012a/b was correlated with IDH mutant status and MGMT promoter mutation in gliomas, and tRFdb-3012a/b and ts-23 tended to be highly expressed in patients with the IDH mutant. The enrichment analysis showed that some tRFdb-3012a/b-related genes were enriched in RNA splicing and processing, the spliceosome pathway and astrocyte molecular signatures. Moreover, the 3' untranslated region of the RBM43 gene was predicted to contain putative binding sites of tRFdb-3012a/b, ts-26 may directly bind to the 3' untranslated region of the HOXA13 gene, and the expressions of both RBM43 and HOXA13 were up-regulated in diffuse gliomas. High RBM43 and HOXA13 expressions were significantly associated with poor survival outcome of glioma patients. Conclusion: These results suggest that tRNA-Leu-CAA-derived tsRNAs (ts-26, tRFdb-3012a, and tRFdb-3012b) could be explored as diagnostic and prognostic biomarkers for diffuse gliomas, and tRFdb-3012a/b and ts-26 may play an important role in the progression of gliomas, through binding RBM43 and HOXA13, respectively.

10.
Pathogens ; 11(9)2022 Sep 05.
Article in English | MEDLINE | ID: mdl-36145444

ABSTRACT

Corynebacterium striatum has developed into a new community-acquired and hospital-acquired multi-drug resistance (MDR) bacterium, and is a potential target pathogen for infection control and antibacterial management projects. In this study, non-duplicate samples of inpatients were collected from a local central hospital. Mass spectrometry showed that 54 C. striatum isolates mainly appeared in secretion and sputum from 14 departments. Protein fingerprint cluster analysis showed that the isolates were divided into four groups, most of which appeared in summer. The drug resistance test showed that all strains had multi-drug resistance, with high resistance rates to lincosamides, quinolones and tetracycline detected. Further analysis of the phylogenetic tree of C. striatum was conducted by cloning the 16S rRNA gene. It was found that isolates in the same department had high homology and tended to be located in the same branch or to be crossed in the same main branch. The strains in the same evolutionary branch group had the same drug resistance. Screening of site-specific recombinant elements revealed that 18 strains had integrase genes with the same sequence. This study shows that there may be mobile genetic elements in clinical isolates that drive gene exchange among strains, thus causing the cross-infection, spread and evolution of pathogenic bacteria in the hospital.

11.
Cancer Causes Control ; 33(10): 1247-1259, 2022 Oct.
Article in English | MEDLINE | ID: mdl-35916964

ABSTRACT

PURPOSE: Lung cancer incidences tend to be higher among males than females in both China and the United States, yet secular incidence patterns are different due to distinct population and environmental exposures. We examined long-term and future trends of lung cancer incidence, as well as the associations of age, period, and cohort effects with gender disparities. METHODS: Using data from the Cancer Incidence in Five Continents from 1978 to 2012, we calculated age-standardized, age-specific incidence, and male-to-female incidence rate ratios (IRR), and conducted an age-period-cohort analysis. The average annual percentage change (AAPC) of the trends was obtained by Joinpoint Regression. Bayesian age-period-cohort analysis was also conducted to project incidences to 2032. RESULTS: In China, age-standardized incidence revealed a decreasing trend among males, but showed increasing trends among the younger age groups (30-54 years) in females. Age-standardized incidence rates of males decreased but remained stable among females from 1972 to 2012 in the United States. Male-to-female incidence rate ratios narrowed in both countries and reversed among younger birth cohorts in the United States. Gender disparities are expected to continue to diminish in both countries, and incidence among females appears to exceed that of males in the United States by around 2023-2027. CONCLUSION: Gender disparities in lung cancer incidence persist and will continue into the future in both countries, but our findings suggested that smoking may play different roles in gender disparities in lung cancer incidence between the two countries. Further population-based epidemiological studies among females in China are imperative.


Subject(s)
Lung Neoplasms , Adult , Bayes Theorem , China/epidemiology , Cohort Studies , Female , Humans , Incidence , Lung Neoplasms/epidemiology , Male , Middle Aged , United States/epidemiology
12.
Planta Med ; 88(14): 1299-1310, 2022 Nov.
Article in English | MEDLINE | ID: mdl-35100652

ABSTRACT

Seven undescribed cytochalasins, multirostratins K - Q (2: -8: ), together with one known analogue, cytochalasin Z3 (1: ), were isolated from the culture of Phoma multirostrata XJ-2-1, an endophytic fungus obtained from the root of Parasenecio albus. Their structures with absolute configurations were determined by 1D and 2D NMR, high-resolution electrospray ionization mass spectrometry (HRESIMS), electronic circular dichroism (ECD), single-crystal X-ray crystallography, and chemical methods. The structure of ascochalasin was revised from Δ 13 to Δ 21 by detailed analysis of the NMR data and by comparison with the data for 7: . In a TRAIL (tumor necrosis factor related apoptosis inducing ligand)-resistance-overcoming experiment, co-treatment of 2: or 6: with TRAIL reduced the cell viability of A549 cells by 30.3% and 27.5% at 10 µM, respectively.


Subject(s)
Ascomycota , Cytochalasins , Humans , Cytochalasins/pharmacology , Cytochalasins/chemistry , Molecular Structure , A549 Cells
13.
Pediatr Nephrol ; 37(2): 275-287, 2022 02.
Article in English | MEDLINE | ID: mdl-34529137

ABSTRACT

BACKGROUND: Acute kidney injury (AKI) is common and it is associated with poor clinical outcomes in premature and low birth weight neonates. This systematic review and meta-analysis was performed to summarize the literature and evaluate the prevalence, risk factors, and mortality of premature and low birth weight neonates with AKI. METHODS: A systematic search in PubMed, Embase, and the Cochrane Library was performed. Studies on the prevalence, risk factors, diagnosis, and outcomes of acute kidney injury in preterm neonates and neonates with low birth weight were included and analyzed. RESULTS: Fifty articles of 10,744 patients were included in this study. The overall rate of AKI from the pooled results of all patients was 25% (95% CI 20-30%) with heterogeneity among studies (I2 = 97%; P < 0.01). Patients with AKI had significantly higher rate of mortality than patients without AKI (odds ratio (OR) = 7.13; 95% CI 5.91-8.60; P < 0.01). CONCLUSIONS: AKI was prevalent and was associated with high mortality rate among preterm and low birth weight neonates.


Subject(s)
Acute Kidney Injury , Acute Kidney Injury/etiology , Female , Humans , Infant, Low Birth Weight , Infant, Newborn , Male , Prevalence , Risk Factors
15.
Front Public Health ; 10: 998174, 2022.
Article in English | MEDLINE | ID: mdl-36684904

ABSTRACT

Introduction: Since 2006, the human papillomavirus (HPV) vaccine has been recommended for females aged 9-26 years in the United States. Aiming to evaluate the early effect of the HPV vaccine on cervical cancer, this study assessed the incidence of cervical cancer by age and histology before and after the introduction of HPV vaccination. Methods: Data on cervical cancer incidence from 1975-2019 were extracted from the Surveillance, Epidemiology, and End Results Program. Joinpoint regression was used to determine temporal trends over time. Future cervical cancer incidence (2015-2039) was projected using Bayesian age-period-cohort analysis. Age-period-cohort (APC) models were created to evaluate age, period, and cohort effects. Results: For overall cervical cancer and cervical squamous cell carcinoma (SCC), incidence rate showed decreasing trends (-0.7%, and -1.0% annually, respectively), whereas cervical adenocarcinoma (AC) incidence continuously increased (2.6% annually). The incidence trends for AC were stable in the 20-24 and 25-29-year age groups, whereas there was an increasing trend in older age groups. Similarly, the projected trend for AC in females aged 20-30 years exhibited a decline, whereas an increase was predicted in the 31-40-year age group, especially in the 35-44 year age group. The birth cohort and period effects in SCC and AC were extracted from APC models. Discussion: During the period of 1975-2019, the incidence of cervical AC remained almost unchanged in the age groups receiving HPV vaccines while increased in the age groups not receiving HPV vaccines. The birth cohort effects of SCC and AC of the cervix provided evidence supporting the effectiveness of the HPV vaccine in preventing cervical cancer.


Subject(s)
Papillomavirus Infections , Papillomavirus Vaccines , Uterine Cervical Neoplasms , Female , Humans , United States/epidemiology , Aged , Adult , Uterine Cervical Neoplasms/epidemiology , Uterine Cervical Neoplasms/prevention & control , Human Papillomavirus Viruses , Papillomavirus Infections/complications , Papillomavirus Infections/epidemiology , Papillomavirus Infections/prevention & control , SEER Program , Papillomavirus Vaccines/therapeutic use , Bayes Theorem
16.
Front Pharmacol ; 13: 962850, 2022.
Article in English | MEDLINE | ID: mdl-36703727

ABSTRACT

Objective: To explore the pharmacological basis and mechanism of Buxue Yimu pills (BYP) in the treatment of anaemia in women from the perspective of metabolomics and network analysis. Materials and Methods: Forty-six women of reproductive age with haemoglobin 70-110 g/L were recruited. Blood samples were collected before and after 4 weeks of oral BYP treatment to assess the changes in haemoglobin, coagulation function, and iron metabolism indices. An integrated analysis of metabolomics (liquid chromatography mass spectrometry) and network analysis was performed to identify the potential pharmacodynamic mechanisms of BYP. Results: After BYP treatment, the haemoglobin level of patients significantly increased from 93.67 ± 9.77 g/L to 109.28 ± 12.62 g/L (p < 0.01), while no significant changes were found in iron metabolism and coagulation-related indicators. A total of 22 differential metabolites were identified after metabolomics analysis, which were mainly related to the inhibition of inflammation and oxidative stress. Integrating pharmacodynamics and metabolomics, a network of drug-active components-targets-metabolic pathways-metabolomics was established. Acetylcholinesterase, phospholipase A2 group IIA, and phospholipase A2 group IVA may be the most promising therapeutic targets. Conclusion: BYP can inhibit inflammation and oxidative stress as well as promote haematopoiesis, potentially improving anaemia.

17.
Huan Jing Ke Xue ; 42(9): 4538-4547, 2021 Sep 08.
Article in Chinese | MEDLINE | ID: mdl-34414754

ABSTRACT

Rational application of nitrogen is an important strategy for increasing yield while reducing environmental pollution due to nitrogen. Pot experiments were conducted to study the effects of different application times on maize yield and soil N2O emission under conditions of equal nitrogen content, and to explore the relationship between the abundance of nitrogen conversion functional genes and N2O emission. Four treatments were used, namely a control (CK, no urea), one-time application (S1, one application of 0.5 g·kg-1 urea+nitrification inhibitor), two separate applications ï¼»S2, two applications of 0.5 g·kg-1 urea (40% and 60% respectively)ï¼½ and three separate applications (S3, 0.5 g·kg-1 urea was divided into three different applications: 20%, 40% and 40% respectively). The results showed that: ① nitrogen application promoted soil acidification, and the degree of soil acidification varied significantly with different application times. More applications of nitrogen led to stronger soil acidification. Nitrogen application significantly increased the ear yield and stem biomass of fresh table maize, but different nitrogen application times may alter soil pH, leading to differences in the degree of nitrogen uptake and utilization in plants. While the S3 treatment significantly reduced soil pH, it also reduced the cumulative nitrogen uptake and utilization in the plants, resulting in a high cumulative N2O emission. Compared with the S3 treatment, the yield was 40.21% and 42.55% higher in the S1 and S2 treatments, and the cumulative N2O emission decreased by 79.4% and 20.9%, respectively. ② N2O emission was positively correlated with the abundance of AOB and nirK genes, which were the main contributors to N2O emission. S1 significantly decreased the abundance of AOB and nirK genes and N2O emissions, while S2 and S3 significantly increased the abundance of nirK and nirS genes and decreased the abundance of nosZ genes after fertilization, promoting N2O emissions. Nitrogen application times affect the functional genes of the nitrogen transformation process, and thus affect N2O emissions. In conclusion, a one-time application of urea combined with DCD only guarantees high maize yield and improves the efficient use of nitrogen, but also reduces greenhouse gas emissions. Thus, it is the recommended nitrogen fertilization mode for the cultivation of fresh corn in Hainan.


Subject(s)
Fertilizers , Zea mays , Agriculture , Fertilizers/analysis , Nitrification , Nitrogen , Nitrous Oxide
18.
Huan Jing Ke Xue ; 42(8): 3931-3942, 2021 Aug 08.
Article in Chinese | MEDLINE | ID: mdl-34309280

ABSTRACT

Based on the rice-vegetable crop rotation model, in-situ measurements of nitrous oxide (N2O) and methane (CH4) emissions were conducted in double-cropping rice fields in Hainan to determine the impact of coconut chaff biochar on greenhouse gas emissions. The experiment involved four treatments:conventional farming fertilization (CON), nitrogen fertilizer combined with 20 t ·hm-2 biochar (B1), nitrogen fertilizer combined with 40 t ·hm-2 biochar (B2), and no nitrogen fertilizer, as the control (CK). The N2O and CH4 emissions were measured using static chamber-gas chromatography during the two paddy seasons, and the global warming potential (GWP) and greenhouse gas intensity (GHGI) were also estimated. The results show that N2O emission dynamics during the early rice season are closely related to the mineral nitrogen content of the soil. The N2O is emitted at the rice seedling and tillering stages after fertilization. The cumulative N2O emission during the early rice season was 0.18-0.76 kg ·hm-2. Compared with the CON treatment, the biochar treatments reduced N2O by 18%-43%, and the B2 treatment resulted in a significant reduction. The addition of biochar may promote the reduction of N2O at the early rice seedling stage and increase N2O emissions by improving the soil NO3--N content at the early rice tillering stage. During the late rice season, N2O is emitted during the heading and maturity stages, and the cumulative N2O emission was 0.17-0.34 kg ·hm-2. The B1 treatment reduced emissions by 37%, and B2 increased emission by only 3%, which is not a significant difference. The peak of CH4 emissions from rice fields appeared in the late phase of the early rice season and prophase of the late rice season. The cumulative emission of CH4 in the early rice season was 3.11-14.87 kg ·hm-2. Compared with CON, the CK treatment increased emission by 39%. The biochar treatment may increase soil aeration and limit the ability of CH4 production in the early rice season, as B1 and B2 treatments reduced CH4 emissions by 28% and 71%. The cumulative CH4 emission in late rice season was 53.1-146.3 kg ·hm-2, and the emission dynamics were significantly positively correlated with NH4+-N content. CK and B1 treatments increased CH4 emissions by 52% and 99%, respectively compared with CON, and the B2 treatment significantly increased CH4 emissions by 176%. Compared with CON, the B1 and B2 treatments increased the yield by 12.0% and 14.3% when applied in the early rice season and by 7.6% and 0.4% when applied in the late rice season, respectively. Due to the increased methane emissions in the late rice season, biochar amendment increased the GWP of the double-cropping rice field, in which the high amount of biochar reached a significant level; different amounts of biochar had no significant effect on the GHGI of the double-cropping rice field. Thus, the application of coconut chaff biochar for the reduction of greenhouse gas emission, from rice fields in hot areas, requires further research.


Subject(s)
Nitrous Oxide , Oryza , Agriculture , Charcoal , China , Cocos , Fertilizers/analysis , Methane/analysis , Nitrous Oxide/analysis , Soil
19.
Huan Jing Ke Xue ; 42(8): 3943-3952, 2021 Aug 08.
Article in Chinese | MEDLINE | ID: mdl-34309281

ABSTRACT

Alternating dry and wet conditions affect the main processes of N2O production, such as nitrification and denitrification. Such conditions are very common in tropical rice-growing areas, such as Hainan. As a type of soil amendment, biochar is widely used to improve physical and chemical properties of soil and to reduce soil greenhouse gas emissions. However, there is a lack of existing in-depth research on the emission reductions of biochar when used in tropical soils that undergo frequently alternating dry and wet conditions. In this experiment, typical paddy soil from northern Hainan was used as the test soil, and corn stalk biochar, carbonized under anaerobic conditions at 400℃, was used as the test biochar. This experiment explored the effects of adding biochar on soil greenhouse gas emissions and microbial-related functional genes under different water management conditions. The experiment comprised a 30 d culture, kept in the dark at 25℃, and a total of six treatments:alternating dry-wet conditions without adding biochar (AWD1), alternating dry-wet conditions with 2% biochar (AWD2), alternating dry-wet conditions with 4% biochar (AWD3), continuous flooding without adding biochar (CF1), continuous flooding with 2% biochar (CF2), and continuous flooding with 4% biochar (CF3). The results showed that:① the addition of biochar under different moisture conditions can reduce N2O emissions in acidic paddy soil (P<0.05, the same below), as the total N2O emissions with the AWD3 treatment were 0.43 mg ·kg-1, which indicates an approximate reduction of 68%, relative to the AWD1 treatment; ② Corn stalk biochar can significantly increase the soil pH under different water management conditions. Compared to the no-biochar treatment, the soil pH increased by 0.5 units on average after cultivation with the addition of biochar, and as the soil NH4+-N content increased, it led to a decrease in Eh. ③ Corn stalk biochar significantly reduces the abundance of ammonia oxidizing bacteria and significantly increases the nosZ gene abundance. However, it decreases the ratio of (nirK+nirS)/nosZ, inhibits the nitrification process, and promotes the reduction of N2O in the denitrification process. Thereby, the addition of corn stalk biochar can reduce N2O emissions. These results show that alternating dry-wet conditions, combined with the addition of corn stalk biochar, are beneficial for reducing N2O emissions in paddy soil, which may have further application in the reduction of agricultural greenhouse gas emissions in northern Hainan.


Subject(s)
Nitrous Oxide , Soil , Charcoal , Nitrous Oxide/analysis , Soil Microbiology , Water , Water Supply
20.
Cancer Causes Control ; 32(10): 1095-1105, 2021 Oct.
Article in English | MEDLINE | ID: mdl-34152517

ABSTRACT

PURPOSE: An increasing incidence of thyroid cancer has been seen in China during the past several decades. The aim of this study was to analyze potential age, period, and cohort effects on the incidence of thyroid cancer in mainland China and to predict new cases up to 2032. METHODS: We calculated age-adjusted and age-specific incidence rates of thyroid cancer, conducted an age-period-cohort analysis of 35,037 thyroid cancer incidence cases reported to Cancer Incidence in Five Continents from 1983 to 2012 in mainland China, and predicted incidence up to 2032 using the Bayesian age-period-cohort method. RESULTS: The age-adjusted overall incidence rate of thyroid cancer increased from 1.93/100,000 in 1983-1987 to 12.18/100,000 in 2008-2012 among females and from 0.77/100,000 in 1983-1987 to 3.89/100,000 in 2008-2012 among males, with a female-to-male ratio of approximately 3.0 during the three decades. Strong birth cohort and period effects on the incidence of thyroid cancer were observed for both sexes, and such an increasing trend is predicted to continue for at least the next 20 years. More than 3.7 million new cases are projected in the 2028-2032 period. CONCLUSION: The increasing trend of thyroid cancer in mainland China will cause a great burden in the future. In addition to the potential impact of improvement in medical diagnostics, potential exposure to risk factors have played a role in the observed rising trend. Further population-based epidemiologic studies are required to identify risk factors to aid in thyroid cancer prevention and control.


Subject(s)
Thyroid Neoplasms , Bayes Theorem , China/epidemiology , Female , Forecasting , Humans , Incidence , Male , Thyroid Neoplasms/epidemiology
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