•Rs differed greatly among the land-use types of the semi-arid temperate grassland.•Soil water availability is a primary constraint on grass ecosystem C processes.•The contribution of Rr to Rs ranged ...from 13 to 62% among the land-use type.•Rs were correlated with aboveground biomass, soil organic matter and root biomass.•Litter decomposition and litter quality also appear to be important biotic factors.
Land use change has greatly affected ecosystem C processes and C exchanges in grassland ecosystems. The aim of this study was to determine the effects of land use (mowing, grazing exclusion, and grazing) on soil respiration (Rs) of a semi-arid temperate grassland during two growing seasons in Inner Mongolia, northern China, and to identify the main factors that affected Rs. During the growing season, Rs for the mowing, grazing exclusion, and grazing land-use types averaged 129, 150, and 194gCm−2yr−1, respectively, in 2011 (a dry year), versus 309, 272, and 262gCm−2yr−1, respectively, in 2012 (a wet year). Root respiration (Rr) accounted for 13–55% of Rs in 2011, versus 10–62% in 2012. Rs was strongly positively correlated with soil moisture for all three land uses, but weakly correlated with soil temperature (R2<0.4 in all cases). Rs was significantly positively correlated with aboveground biomass (R2=0.834), soil organic matter (R2=0.765), root biomass (R2=0.704), lignin mass loss rate (R2=0.422), and the cellulose mass loss rate (R2=0.849) and significantly negatively correlated with the litter C/N (R2=0.609). The temperature sensitivity (Q10) exhibited large monthly changes, and ranged from 0.52 to 2.12. Rainfall plays a dominant role in soil respiration: precipitation increased soil respiration, but the response differed among the land-use types. Thus, soil water availability is a primary constraint on plant growth and ecosystem C processes. Soil temperature plays a secondary role. Litter decomposition rates and litter quality also appear to be important.
The spikelet number per spike (SNS) contributes greatly to grain yield in wheat. Identifying various genes that control wheat SNS is vital for yield improvement. This study used a recombinant inbred ...line population genotyped by the Wheat55K single-nucleotide polymorphism array to identify two major and stably expressed quantitative trait loci (QTLs) for SNS. One of them (QSns.sau-2SY-2D.1) was reported previously, while the other (QSns.sau-2SY-7A) was newly detected and further analyzed in this study. QSns.sau-2SY-7A had a high LOD value ranging from 4.46 to 16.00 and explained 10.21–40.78％ of the phenotypic variances. QSns.sau-2SY-7A was flanked by the markers AX-110518554 and AX-110094527 in a 4.75-cM interval on chromosome arm 7AL. The contributions and interactions of both major QTLs were further analyzed and discussed. The effect of QSns.sau-2SY-7A was successfully validated by developing a tightly linked kompetitive allele specific PCR marker in an F2:3 population and a panel of 101 high-generation breeding wheat lines. Furthermore, several genes including the previously reported WHEAT ORTHOLOG OF APO1 (WAPO1), an ortholog of the rice gene ABERRANT PANICLE ORGANIZATION 1 (APO1) related to SNS, were predicted in the interval of QSns.sau-2SY-7A. In summary, these results revealed the genetic basis of the multi-spikelet genotype of wheat line 20828 and will facilitate subsequent fine mapping and breeding utilization of the major QTLs.
AIMS: We tested the responses of soil respiration to irrigation, at different proportions of field capacity, in constructed grasslands in the Inner Mongolia Autonomous Region of northern China, and ...tried to identify the underlying physiological mechanisms. METHODS: The experiment included a legume (Medicago sativa) and a forage grass (Elymus nutans) in sole-crops and a mixed sowing, with four water treatments: a control and three levels of irrigation (low, medium, and high) at three application times: during the regreening, elongation, and heading stages. RESULTS: The soil respiration rate (R ₛ) responded strongly to water addition. Irrigation increased the cumulative growing season R ₛ, which ranged from 257 g C m⁻² years⁻¹ to 500 g C m⁻² years⁻¹ for M. sativa, from 299 to 391 g C m⁻² years⁻¹ for E. nutans + M. sativa, and from 209 to 296 g C m⁻² years⁻¹ for E. nutans. Irrigation increased the cumulative R ₛ by 7 to 49 %. R ₛ of the grass–legume mixture was 1.2 to 1.4 times the corresponding values in the E. nutans plots. In addition to the effects of soil temperature and moisture content, R ₛ was explained by differences in the net photosynthetic rate and in microbial biomass. Water addition increased Q ₁₀, which was strongly and positively correlated with the total C, C/N ratio, and cellulose content of the plants. CONCLUSIONS: R ₛ responded strongly to irrigation, although the response differed between the two species. The grass–legume mixtures showed increased R ₛ compared to values in the grass sole-crop. R ₛ appears to be determined by moisture and temperature, but also by the net photosynthetic rate and by microbial properties such as microbial biomass.
Purpose
This study aimed to investigate the gut microbiome composition in pregnant women with digestive diseases to analyze the relationships between the microflora changes and digestive diseases ...during pregnancy.
Methods
Fecal samples obtained from 71 pregnant women six acute fatty liver (AF group), 21 constipation (C group), 24 excessive vomiting (V group) and 20 normal pregnancy (CP group) and 26 non-pregnant (NP group) women were subjected to 16 s rRNA sequencing. Differential analysis of intestinal flora at the genera level was performed.
Results
The relative abundance of
Coprobacillus
,
Acinetobacter
,
Enterococcus
,
Weissella
and
Lysinibacillus
was increased in the digestive diseases (AF, C and V) groups compared with CP group, whereas that of five common genera, including
Terrisporobacter
,
Dysgonomonas
,
Adlercreutzia
,
Fusicatenibacter
and
Blautia
, was decreased in digestive diseases groups. Additionally, in digestive diseases (AF, C and V) groups, the abundance of 13 common genera, such as
Carnobacterium
,
Coprobacillus
and
Psychrobacter
, was higher than NP group, whereas that of 27 common genera, such as
Blautia
and
Terrisporobacter
, was lower than NP group. About 69 genera were differentially abundant between AF and C groups; two genera (
Aerococcus
and
Senegalimassilia
) were identified between AF and V groups; moreover, total 63 genera were obtained between C and V groups.
Conclusion
Our data revealed that the abundance of
Acinetobacter
,
Enterococci
,
Paenibacillus
,
Blautia
and
Collinsella
might be associated with the digestive diseases during pregnancy. These findings further supported the idea that targeting the gut microbiota could be a new prevention or therapeutic approach for improving digestive diseases during pregnancy.
We show herein the phosphatase‐like catalytic activity of coordination polymers obtained after adding Ag+‐ions to thiols bearing hydrophobic alkyl chains terminated with a 1,4,7‐triazacyclononane ...(TACN) group. The subsequent addition of Zn2+ ‐ions to the self‐assembled polymers resulted in the formation of multivalent metal coordination polymers capable of catalysing the transphosphorylation of an RNA‐model compound (2‐hydroxypropyl‐4‐nitrophenyl phosphate, HPNPP) with high reactivity. Analysis of a series of metal ions showed that the highest catalytic activity was obtained when Ag+‐ions were used as the first metal ions to construct the backbone of the coordination polymer through interaction with the ‐SH group followed by Zn2+‐ions as the second metal ions complexed by the TACN‐macrocycle. Furthermore, it was demonstrated that the catalytic activity could be modulated by changing the length of the hydrophobic alkyl chain.
A series of self‐assembled multivalent Ag‐SR coordination polymers with high phosphatase‐like activity have been developed. This work represents a new alternative for the future rational design of highly efficient catalysts for hydrolysis of phosphates and carboxylates.
De-domestication is a unique evolutionary process during which crops re-acquire wild-like traits to survive and persist in agricultural fields without the need for human cultivation. The ...re-acquisition of seed dispersal mechanisms is crucial for crop de-domestication. Common wheat is an important cereal crop worldwide. Tibetan semi-wild wheat is a potential de-domesticated common wheat subspecies. However, the crucial genes responsible for its brittle rachis trait have not been identified.
Genetic mapping, functional analyses and phylogenetic analyses were completed to identify the gene associated with Qbr.sau-5A, which is a major locus for the brittle rachis trait of Tibetan semi-wild wheat.
The cloned Qbr.sau-5A gene is a new Q allele (Qt
) with a 161-bp transposon insertion in exon 5. Although Qt
is expressed normally, its encoded peptide lacks some key features of the APETALA2 family. The abnormal functions of Q
t in developing wheat spikes result in brittle rachises. Phylogenetic and genotyping analyses confirmed that Qt
originated from Q in common wheat and is naturally distributed only in Tibetan semi-wild wheat populations.
The identification of Qt
provides new evidence regarding the origin of Tibetan semi-wild wheat, and new insights into the re-acquisition of wild traits during crop de-domestication.
Various plant species contain terpene secondary metabolites, which disrupt insect growth and development by affecting the activity of juvenile hormone-degrading enzymes, and the juvenile hormone (JH) ...titers maintained in insects. Nerolidol, a natural sesquiterpenol belonging to the terpenoid group, exhibits structural similarities to insect JHs. However, the impact of nerolidol on insect growth and development, as well as its underlying molecular mechanism, remains unclear. Here, the effects of nerolidol on Spodoptera exigua were investigated under treatment at various sub-lethal doses (4.0 mg/mL, 1.0 mg/mL, 0.25 mg/mL). We found that a higher dose (4.0 mg/mL) of nerolidol significantly impaired the normal growth, development, and population reproduction of S. exigua, although a relatively lower dose (0.25 mg/mL) of nerolidol had no significant effect on this growth and development. Combined transcriptome sequencing and gene family analysis further revealed that four juvenile hormone esterase (JHE)-family genes that are involved in juvenile hormone degradation were significantly altered in S. exigua larvae after nerolidol treatment (4.0 mg/mL). Interestingly, the juvenile hormone esterase-like (JHEL) gene Sexi006721, a critical element responsive to nerolidol stress, was closely linked with the significant augmentation of JHE activity and JH titer in S. exigua (R2 = 0.94, p < 0.01). Taken together, we speculate that nerolidol can function as an analog of JH by modulating the expression of the enzyme genes responsible for degrading JH, resulting in JH disorders and ultimately disrupting the development of insect larvae. This study ultimately provides a theoretical basis for the sustainable control of S. exigua in the field whilst proposing a new perspective for the development of novel biological pesticides.
Neurotrophins are a family of growth factors that regulate neural survival, development, function and plasticity in the central and the peripheral nervous system. There are four neurotrophins: nerve ...growth factor (NGF), brain-derived neurotrophic factor (BDNF), neurotrophin-3 (NT-3) and NT-4. Among them, BDNF is the most studied due to its high expression in the brain. Over the past two decades, BDNF and its receptor tropomyosin receptor kinase B (TrkB) have been reported to be upregulated in a wide range of tumors. This activated signal stimulates a series of downstream pathways, including phosphoinositide 3-kinase/protein kinase B, Ras-Raf-mitogen activated protein kinase kinase-extracellular signal-regulated kinases, the phospholipase-C-γ pathway and the transactivation of epidermal growth factor receptor. Activation of these signaling pathways induces oncogenic effects by increasing cancer cell growth, proliferation, survival, migration and epithelial to mesenchymal transition, and decreasing anoikis, relapse and chemotherapeutic sensitivity. The present review summarizes recent findings to discuss the role of BDNF in tumors, the underlying molecular mechanism, targeting Trk receptors for treatment of cancers and its potential risk.
This study aims to investigate the predictive value of the combined index smni(skeletal muscle index (SMI)-prognostic nutrition index(PNI)) for the postoperative survival of patients with advanced ...gastric cancer(AGC).
650 patients with AGC from two centers (290 cases from the First Affiliated Hospital of Dalian University and 360 points from the Fujian Medical University Union Hospital) were selected as the study subjects based on unified screening criteria. Clinical data, preoperative abdominal CT images, results of hematology-related examinations, tumor-related characteristics, and surgical and follow-up data of the patients were collected and organized. The L3 vertebral level muscle area was measured using computer-assisted measurement techniques, and the skeletal muscle index(SMI) was calculated based on this measurement. The prognostic nutrition index (PNI) was calculated based on serum albumin and lymphocyte count indicators. The Kaplan-Meier survival analysis of data from the First Affiliated Hospital was used to determine that SMI and PNI are significantly correlated with the postoperative survival rate of patients with advanced gastric cancer. Based on this, a novel combined index smni was fitted and stratified for risk. Cox proportional hazards regression analysis was used to determine that the index smni is an independent prognostic risk factor for patients with AGC after surgery. The ROC curve was used to describe the predictive ability of the new combined index and its importance and predictive power in predicting postoperative survival of patients with AGC, which was verified in the data of Fujian Medical University Union Hospital.
The Kaplan-Meier curve analysis of the combined indicator smni Is clearly associated with long-term survival(3-year OS (P < 0.001) and DSS (P < 0.001)), univariate analysis and multivariate analysis showed that smni was an independent prognostic risk factor, The ROC curve for the first center 3-year OS(AUC = 0.678), DSS(AUC = 0.662) show good predictive ability and were validated in the second center.
The combined index smni has a good predictive ability for the postoperative survival rate of patients with AGC and is expected to provide a new reference basis and more accurate and scientific guidance for the postoperative management and treatment of patients with AGC.
Bristol stool form 1 and 2 is an important predictor of inadequate bowel preparation.
To evaluate the efficacy of supplemental preparation in bowel cleansing quality among patients with Bristol stool ...form 1 and 2, as well as the feasibility of tailored bowel preparation guided by Bristol stool form scale.
Patients with Bristol stool form 1 and 2 from 3 Chinese tertiary hospitals randomly received either 2 L PEG-ELP (group A) or 10 mg bisacodyl plus 2 L PEG-ELP (group B); patients with Bristol stool form 3 to 7 received 2 L PEG-ELP (group C) for bowel preparation. The primary endpoint is the rate of adequate bowel reparation for the whole colon. The adequate bowel preparation rate for separate colon segments, the polyp detection rate (PDR), tolerability, acceptability, sleeping quality and compliance were evaluated as secondary endpoints.
700 patients were randomized. In per-protocol analysis, patients in group B attained significantly higher successful preparation rate than group A (88.7% vs. 61.2%, p<0.001) and similar with group C (88.7% vs. 85.0%, p = 0.316). The PDR in group B was significantly higher than group A (43.2% vs. 25.7%, p<0.001). Acceptability was much higher in group B and C.
10 mg bisacodyl plus 2 L PEG-ELP can significantly improve both bowel preparation quality and PDR in patients with Bristol stool form 1 and 2. Bristol stool form scale may be an easy and efficient guide for tailored bowel preparation before colonoscopy.
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