Climate, litter quality and radiation duration jointly regulate the net effect of UV radiation on litter decomposition.

Photodegradation via ultraviolet (UV) radiation is an important factor driving plant litter decomposition. Despite increasing attention to the role of UV photodegradation in litter decomposition, the specific impact of UV radiation on the plant litter decomposition stage within biogeochemical cycles remains unclear at regional and global scales. To clarify the variation rules of magnitude of UV effect on plant litter decomposition and their regulatory factors, we conducted a meta-analysis based on 54 published papers. Our results indicated that UV significantly promoted the mass loss of litter by facilitating decay of carbonaceous fractions and release of nitrogen and phosphorus. The promotion effect varied linearly or non-linearly with the time that litter exposed to UV, and with climatic factors. The UV effect on litter decomposition decreased first than increased on precipitation and temperature gradients, reaching its minimum in the area with a precipitation of 400-600 mm, and a temperature of 15-20 °C. This trend might be attributed to a potential equilibrium between the photofacilitation and photo-inhibition effects of UV under this condition. This variation in UV effect on precipitation gradient was in agreement with the fact that UV photodegradation effect was weakest in grassland ecosystems compared to that in forest and desert ecosystems. In addition, initial litter quality significantly influenced the magnitude of UV effect, but had no influence on the correlation between UV effect and climate gradient. Litter with lower initial nitrogen and lignin content shown a greater photodegradation effect, whereas those with higher hemicellulose and cellulose content had a greater photodegradation effect. Our study provides a comprehensive understanding of photodegradation effect on plant litter decomposition, indicates potentially substantial impacts of global enhancements of litter decomposition by UV, and highlights the necessity to quantify the contribution of photochemical minerallization pathway and microbial degradation pathway in litter decomposition.

Increased levels of villus-derived exosomal miR-29a-3p in normal pregnancy than uRPL patients suppresses decidual NK cell production of interferon-γ and exerts a therapeutic effect in abortion-prone mice.

OBJECTIVE: Recurrent pregnancy loss (RPL) patients have higher absolute numbers of decidual natural killer (dNK) cells with elevated intracellular IFN-γ levels leading to a pro-inflammatory cytokine milieu, which contributes to RPL pathogenesis. The main objective of this study was twofold: first to explore the regulatory effects and mechanisms of villus-derived exosomes (vEXOs) from induced abortion patients or RPL patients at the level of intracellular IFN-γ in dNK cells; second to determine the validity of application of vEXOs in the treatment of unexplained RPL (uRPL) through in vitro experiments and mouse models. METHODS: Exosomes were isolated from villus explants by ultracentrifugation, co-cultured with dNK cells, and purified by enzymatic digestion and magnetically activated cell sorting. Flow cytometry, enzyme-linked immunosorbent assays, and RT-qPCR were used to determine IFN-γ levels. Comparative miRNA analysis of vEXOs from induced abortion (IA) and uRPL patients was used to screen potential candidates involved in dNK regulation, which was further confirmed by luciferase reporter assays. IA-vEXOs were electroporated with therapeutic miRNAs and encapsulated in a China Food and Drug Administration (CFDA)-approved hyaluronate gel (HA-Gel), which has been used as a clinical biomaterial in cell therapy for > 30 years. In vivo tracking was performed using 1,1-dioctadecyl-3,3,3,3-tetramethylindotricarbocyaine iodide (DiR) labelling. Tail-vein and uterine horn injections were used to evaluate therapeutic effects of the engineered exosomes in an abortion-prone mouse model (CBA/J × DBA/2 J). Placental growth was evaluated based on placental weight. IFN-γ mRNA levels in mouse placentas were measured by RT-qPCR. RESULTS: IFN-γ levels were significantly higher in dNK cells of uRPL patients than in IA patients. Both uRPL-vEXOs and IA-vEXOs could be efficiently internalized by dNK cells, whereas uRPL-vEXOs could not reduce the expression of IFN-γ by dNK cells as much as IA-vEXOs. Mechanistically, miR-29a-3p was delivered by vEXOs to inhibit IFN-γ production by binding to the 3' UTR of IFN-γ mRNA in dNK cells. For in vivo treatment, application of the HA-Gel effectively prolonged the residence time of vEXOs in the uterine cavity via sustained release. Engineered vEXOs loaded with miR-29a-3p reduced the embryo resorption rate in RPL mice with no signs of systemic toxicity. CONCLUSION: Our study provides the first evidence that villi can regulate dNK cell production of IFN-γ via exosome-mediated transfer of miR-29a-3p, which deepens our understanding of maternal-fetal immune tolerance for pregnancy maintenance. Based on this, we developed a new strategy to mix engineered vEXOs with HA-Gel, which exhibited good therapeutic effects in mice with uRPL and could be used for potential clinical applications in uRPL treatment.

TSG6-Exo@CS/GP Attenuates Endometrium Fibrosis by Inhibiting Macrophage Activation in a Murine IUA Model.

Intrauterine adhesion (IUA) is characterized by the formation of fibrous scar tissue within the uterine cavity, which significantly impacts female reproductive health and even leads to infertility. Unfortunately, severe cases of IUA currently lack effective treatments. This study presents a novel approach that utilizes tumor necrosis factor-(TNF) stimulated gene 6 (TSG6)-modified exosomes (Exos) in conjunction with an injectable thermosensitive hydrogel (CS/GP) to mitigate the occurrence of IUA by reducing endometrium fibrosis in a mouse IUA model. This study demonstrate that TSG6-modified Exos effectively inhibits the activation of inflammatory M1-like macrophages during the initial stages of inflammation and maintains the balance of macrophage phenotypes (M1/M2) during the repair phase. Moreover, TSG6 inhibits the interaction between macrophages and endometrial stromal fibroblasts, thereby preventing the activation of stromal fibroblasts into myofibroblasts. Furthermore, this research indicates that CS/GP facilitates the sustained release of TSG6-modified Exos, leading to a significant reduction in both the manifestations of IUA and the extent of endometrium fibrosis. Collectively, through the successful construction of CS/GP loaded with TSG6-modified Exos, a reduction in the occurrence and progression of IUA is achieved by mitigating endometrium fibrosis. Consequently, this approach holds promise for the treatment of IUA.

High estrogen during ovarian stimulation induced loss of maternal imprinted methylation that is essential for placental development via overexpression of TET2 in mouse oocytes.

BACKGROUND: Ovarian stimulation (OS) during assisted reproductive technology (ART) appears to be an independent factor influencing the risk of low birth weight (LBW). Previous studies identified the association between LBW and placenta deterioration, potentially resulting from disturbed genomic DNA methylation in oocytes caused by OS. However, the mechanisms by which OS leads to aberrant DNA methylation patterns in oocytes remains unclear. METHODS: Mouse oocytes and mouse parthenogenetic embryonic stem cells (pESCs) were used to investigate the roles of OS in oocyte DNA methylation. Global 5-methylcytosine (5mC) and 5-hydroxymethylcytosine (5hmC) levels were evaluated using immunofluorescence or colorimetry. Genome-wide DNA methylation was quantified using an Agilent SureSelectXT mouse Methyl-Seq. The DNA methylation status of mesoderm-specific transcript homologue (Mest) promoter region was analyzed using bisulfite sequencing polymerase chain reaction (BSP). The regulatory network between estrogen receptor alpha (ERα, ESR1) and DNA methylation status of Mest promoter region was further detected following the knockdown of ERα or ten-eleven translocation 2 (Tet2). RESULTS: OS resulted in a significant decrease in global 5mC levels and an increase in global 5hmC levels in oocytes. Further investigation revealed that supraphysiological ß-estradiol (E2) during OS induced a notable decrease in DNA 5mC and an increase in 5hmC in both oocytes and pESCs of mice, whereas inhibition of estrogen signaling abolished such induction. Moreover, Tet2 may be a direct transcriptional target gene of ERα, and through the ERα-TET2 axis, supraphysiological E2 resulted in the reduced global levels of DNA 5mC. Furthermore, we identified that MEST, a maternal imprinted gene essential for placental development, lost its imprinted methylation in parthenogenetic placentas originating from OS, and ERα and TET2 combined together to form a protein complex that may promote Mest demethylation. CONCLUSIONS: In this study, a possible mechanism of loss of DNA methylation in oocyte caused by OS was revealed, which may help increase safety and reduce epigenetic abnormalities in ART procedures.

Identifying a panel of nine genes as novel specific model in endometriosis noninvasive diagnosis.

OBJECTIVE: To study biomarkers to develop a novel diagnosis model for endometriosis and validate it using clinical samples. DESIGN: We used publicly available data sets and weighted gene coexpression network analysis to identify differentially expressed genes. Ten machine learning algorithms were used to develop an integrative model for predicting endometriosis. The accuracy and robustness of the model were validated using data sets and clinical samples. SETTING: Department of Obstetrics and Gynecology, Tangdu Hospital, Air Force Medical University, Xi'an, Shaanxi, China. PATIENT(S): The study included clinical patients between the ages of 20 and 40 years who required laparoscopic surgery and who had not undergone hormone therapy within the previous 3 months. All the healthy individuals had given birth to a child at least once in their lives. Patients with inflammatory conditions, malignant diseases, immune diseases, myoma, or adenomyosis were excluded. Paraffin blocks of the samples were collected (case, n = 5; control, n = 5). Blood samples of 58 individuals were collected (case, n = 28; control, n = 30). INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): The areas under the receiver operator characteristic curve of our diagnostic model were measured for data sets and clinical samples. Multiplex immunohistochemical staining and real-time quantitative polymerase chain reaction assays were used for the validation of the model from tissue slides and peripheral blood samples. RESULT(S): A nine-gene panel endometriosis messenger RNA score (EMScore), was constructed to distinguish the patients with endometriosis from healthy individuals using algorithms. The EMScore accurately predicted endometriosis, and the areas under the receiver operator characteristic curve of our diagnostic model were 0.920, and 0.942 for tissue and blood samples, respectively. Moreover, the EMScore outperformed other acknowledged signatures for predicting endometriosis across seven clinical cohorts. Overall, the EMScore constitutes a sensitive and specific noninvasive diagnostic method for endometriosis. CONCLUSION(S): We developed the EMScore, a novel model that can aid in the diagnosis of endometriosis using peripheral blood samples. This study will contribute to the development of improved clinical noninvasive and sensitive diagnostic tools for endometriosis. These nine genes might be potential target molecules for treating endometriosis.

Protective effect and mechanism of styrax on ischemic stroke rats: metabonomic insights by UPLC-Q/TOF-MS analysis.

CONTEXT: Styrax is used for prevention and treatment of cerebrovascular diseases. However, the underlying mechanism remains unclear. OBJECTIVE: To elucidate styrax's anti-ischemic stroke protective effects and underlying mechanisms. MATERIALS AND METHODS: An ischemic-stroke rat model was established based on middle cerebral artery occlusion (MCAO). Sprague-Dawley rats were randomly assigned to the following groups (n = 10) and administered intragastrically once a day for 7 consecutive days: sham, model, nimodipine (24 mg/kg), styrax-L (0.1 g/kg), styrax-M (0.2 g/kg) and styrax-H (0.4 g/kg). Neurological function, biochemical assessment, and ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry (UPLC-Q/TOF-MS)-based serum metabonomics were used to elucidate styrax's cerebral protective effects and mechanisms. Pearson correlation and western blot analyses were performed to verify. RESULTS: The addition of 0.4 g/kg styrax significantly reduced cerebral infarct volume and neurobehavioral abnormality score. Different doses of styrax also decrease MDA, TNF-α, IL-6, and IL-1ß, and increase SOD and GSH-Px in ischemic-stroke rats (p < 0.05; MDA, p < 0.05 only at 0.4 g/kg dose). Biochemical indicators and metabolic-profile analyses (PCA, PLS-DA, and OPLS-DA) also supported styrax's protective effects. Endogenous metabolites (22) were identified in ischemic-stroke rats, and these perturbations were reversible via styrax intervention, which is predominantly involved in energy metabolism, glutathione and glutamine metabolism, and other metabolic processes. Additionally, styrax significantly upregulated phosphorylated AMP-activated protein kinase and glutaminase brain-tissue expression. CONCLUSION: Styrax treatment could ameliorate ischemic-stroke rats by intervening with energy metabolism and glutamine metabolism. This can help us understand the mechanism of styrax, inspiring more clinical application and promotion.

Metabolomic responses to the mechanical wounding of Catharanthus roseus' upper leaves.

Purpose: Plant secondary metabolites are used to treat various human diseases. However, it is difficult to produce a large number of specific metabolites, which largely limits their medicinal applications. Many methods, such as drought and nutrient application, have been used to induce the biosynthetic production of secondary metabolites. Among these secondary metabolite-inducing methods, mechanical wounding maintains the composition of secondary metabolites with little potential risk. However, the effects of mechanical stress have not been fully investigated, and thus this method remains widely unused. Methods: In this study, we used metabolomics to investigate the metabolites produced in the upper and lower leaves of Catharanthus roseus in response to mechanical wounding. Results: In the upper leaves, 13 different secondary metabolites (three terpenoid indole alkaloids and 10 phenolic compounds) were screened using an orthogonal partial least squares discriminant analysis (OPLS-DA) score plot. The mechanical wounding of different plant parts affected the production of secondary metabolites. Specifically, when lower leaves were mechanically wounded, the upper leaves became a strong source of resources. Conversely, when upper leaves were injured, the upper leaves themselves became a resource sink. Changes in the source-sink relationship reflected a new balance between resource tradeoff and the upregulation or downregulation of certain metabolic pathways. Conclusion: Our findings suggest that mechanical wounding to specific plant parts is a novel approach to increase the biosynthetic production of specific secondary metabolites. These results indicate the need for a reevaluation of production practices for secondary metabolites from select commercial plants.

The Role of Taraxacum mongolicum in a Puccinellia tenuiflora Community under Saline-Alkali Stress.

Coexisting salt and alkaline stresses seriously threaten plant survival. Most studies have focused on halophytes; however, knowledge on how plants defend against saline-alkali stress is limited. This study investigated the role of Taraxacum mongolicum in a Puccinellia tenuiflora community under environmental saline-alkali stress to analyse the response of elements and metabolites in T. mongolicum, using P. tenuiflora as a control. The results show that the macroelements Ca and Mg are significantly accumulated in the aboveground parts (particularly in the stem) of T. mongolicum. Microelements B and Mo are also accumulated in T. mongolicum. Microelement B can adjust the transformation of sugars, and Mo contributes to the improvement in nitrogen metabolism. Furthermore, the metabolomic results demonstrate that T. mongolicum leads to decreased sugar accumulation and increased amounts of amino acids and organic acids to help plants resist saline-alkali stress. The resource allocation of carbon (sugar) and nitrogen (amino acids) results in the accumulation of only a few phenolic metabolites (i.e., petunidin, chlorogenic acid, and quercetin-3-O-rhamnoside) in T. mongolicum. These phenolic metabolites help to scavenge excess reactive oxygen species. Our study primarily helps in understanding the contribution of T. mongolicum in P. tenuiflora communities on coping with saline-alkali stress.

Effectiveness and Safety of Early Short-Course, Moderate- to High-Dose Glucocorticoids for the Treatment of Stevens-Johnson Syndrome/Toxic Epidermal Necrolysis: A Retrospective Study.

Objective: To summarise the clinical characteristics of patients with Stevens-Johnson syndrome/toxic epidermal necrolysis syndrome (SJS/TEN) and analyse the efficacy and safety of systemic glucocorticoid therapy. Methods: This study was a retrospective study of 56 patients with SJS/TEN who had been systematically treated with glucocorticoids in the dermatology ward of Peking University Third Hospital from 2010 to 2020. The clinical characteristics, treatment regimen, effects on underlying diseases, incidence and outcome of hormone-related adverse reactions and skin lesion prognosis were summarised and analysed for each patient. Results: ① The allergenic drugs were found to be antibiotics (31.51%), antipyretic and analgesics (21.92%), traditional Chinese medicines and health products (15.07%) and neuropsychiatric drugs (13.70%). ② Based on the 56 patients' scores of toxic epidermal necrosis at admission, the actual mortality rate was 1.8% (1/56), which was significantly lower than the average expected mortality rate of 15.0% (P = 0.032; standardised mortality ratio = 0.13; 95% confidence interval: 0.00-0.53). ③ A total of 33 patients (58.9%) had underlying diseases, of which 10 patients (30.3%) had underlying diseases that fluctuated during treatment but stabilised after symptomatic treatment. ④ During treatment, 73.2% (41/56) of patients had complications that may have been related to systemic glucocorticoids; 97.6% (40/41) had mild symptoms, and 92.7% (38/41) had improved/recovered complications at the time of discharge. Conclusion: ① Antibiotics are still the most common sensitising drugs, and traditional Chinese medicine and health products are also common sensitising drugs. ② Early systemic application of medium- to high-dose glucocorticoids is effective in the treatment of SJS/TEN, and it is beneficial in reducing mortality. ③ The short-term application of medium- to high-dose hormone therapy for SJS/TEN has little effect on underlying diseases. The related complications are mostly mild, and the treatment is safe.

Transcriptomic Analysis of Fusarium oxysporum Stress-Induced Pathosystem and Screening of Fom-2 Interaction Factors in Contrasted Melon Plants.

Fusarium wilt is one of the most destructive and less controllable diseases in melon, which is usually caused by fusarium oxysporum. In this study, transcriptome sequencing and Yeast Two-Hybrid (Y2H) methods were used for quantification of differentially expressed genes (DEGs) involved in fusarium oxysporum (f. sp. melonis race 1) stress-induced mechanisms in contrasted melon varieties (M4-45 "susceptible" and MR-1 "resistant"). The interaction factors of Fom-2 resistance genes were also explored in response to the plant-pathogen infection mechanism. Transcriptomic analysis exhibited total 1,904 new genes; however, candidate DEGs analysis revealed a total of 144 specific genes (50 upregulated and 94 downregulated) for M4-45 variety and 104 specific genes (71 upregulated and 33 downregulated) for MR-1 variety, respectively. The analysis of Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway depicted some candidate DEGs, including Phenylalanine metabolism, phenylpropane biosynthesis, plants-pathogen interaction, and signal transduction of plant hormones, which were mainly involved in disease resistance metabolic pathways. The weighted gene co-expression network analysis (WGCNA) analysis revealed a strong correlation module and exhibited the disease resistance-related genes encoding course proteins, transcription factors, protein kinase, benzene propane biosynthesis path, plants-pathogen interaction pathway, and glutathione S-transferase. Meanwhile, the resistance-related specific genes expression was relatively abundant in MR-1 compared to the M4-45, and cell wall-associated receptor kinases (MELO3C008452 and MELO3C008453), heat shock protein (Cucumis_melo_newGene_172), defensin-like protein (Cucumis_melo_newGene_5490), and disease resistance response protein (MELO3C016325), activator response protein (MELO3C021623), leucine-rich repeat receptor protein kinase (MELO3C024412), lactyl glutathione ligase (Cucumis_melo_newGene_36), and unknown protein (MELO3C007588) were persisted by exhibiting the upregulated expressions. At the transcription level, the interaction factors between the candidate genes in response to the fusarium oxysporum induced stress, and Y2H screening signified the main contribution of MYB transcription factors (MELO3C009678 and MELO3C014597), BZIP (MELO3C011839 and MELO3C019349), unknown proteins, and key enzymes in the ubiquitination process (4XM334FK014). The candidate genes were further verified in exogenously treated melon plants with f. oxysporum (Fom-2, Race 1), Abscisic acid (ABA), Methyl Jasmonite (MeJA), and Salicylic acid (SA), using the fluorescence quantitative polymerase chain reaction (qRT-PCR) analysis. The overall expression results indicated that the SA signal pathway is involved in effective regulation of the Fom-2 gene activity.

Primary Kaposi's Sarcoma of the Nasal Cavity: Clinical Experience and Review of the Literature.

Kaposi's sarcoma (KS) is a vascular sarcoma derived from vascular endothelial cells and presents with multiple lesions. It mainly appears on the skin and oral mucosa, usually in the face, oral mucosa, and genitals. Very few cases of primary lesions in the nasal cavity have been reported. It is often difficult to diagnose only by imaging examination. Here, we describe a case of KS in a patient who was human immunodeficiency virus (HIV)-negative, in which the primary sites were the nasal mucosa and nasal septum. A diagnosis was made according to the patient's clinical presentation, physical examination, laboratory examination, imaging examination, and histopathological results. We used surgical resection combined with chemotherapy, with 6 months' postoperative follow-up without recurrence. We reviewed the relevant literature to identify similar cases and summarize the findings reported on this rare manifestation of KS. We recommend that, where possible, antiviral therapy such as interferon, and regular review should continue, to improve the survival rate and patients' quality of life.

A Pilot Study to Assess the Reliability of Digital Image-Based PASI Scores Across Patient Skin Tones and Provider Training Levels.

INTRODUCTION: The ability to perform psoriasis skin assessments remotely through digital image-based psoriasis area and severity index (DIB-PASI) would be a valuable tool for psoriasis clinical trials. An ideal teledermatological assessment would be robust across patients of diverse skin tones as well as across assessors of varying experience levels. In this pilot study, we evaluated the reliability of face-to-face (FTF) versus DIB-PASI scores determined by trained clinical assessors with a spectrum of experience and with patients of different skin tones. METHODS: Fourteen subjects of varying skin tones with moderate-to-severe plaque psoriasis were treated with adalimumab. In-person PASI assessments and digital photography were performed in the clinic at weeks 0, 12, and 24. Photographs were reviewed by four independent assessors to derive a digital image-based PASI score. The concordance of face-to-face PASI (FTF-PASI) and DIB-PASI were analyzed across patient and assessor factors. RESULTS: Overall concordance between FTF-PASI and DIB-PASI was high (ICC 0.82, p < 0.0001), with good agreement across individual assessors. When analyzed by PASI score component or body region, digital assessors also demonstrated good agreement with the FTF assessor. Similarly, DIB-PASI showed high concordance with FTF-PASI for patients with light skin tones and patients with medium-to-dark skin tones, and across clinical training levels. CONCLUSION: Overall, PASI scores derived from digital images showed good agreement with those determined in person. Importantly, these remote assessments were reliable for both light and medium-to-dark skin tones, and robust to training level of the assessor. The findings from this pilot study lay the foundation for expanding teledermatology-based clinical trials for patients with psoriasis and enabling accurate, remote monitoring of disease severity and therapy response.

Individualized Nutritional Support for Hospitalized Patients With Oropharyngeal Dysphagia After Stroke: A Randomized Controlled Trial.

Objectives: Post-stroke dysphagia may cause aspiration pneumonia, malnutrition, dehydration, and other complications. However, data on the effects of nutritional supplementation and its value after stroke are insufficient. We aimed to evaluate the effect of an individualized 1-week nutrition intervention program on swallowing function and nutritional status in stroke patients with oropharyngeal dysphagia. Methods: This study comprised the control group receiving oral nutritional support and continuous nasogastric tube feeding according to the results of the water swallow test (WST). The intervention group additionally underwent a volume-viscosity swallowing test (V-VST) and intermittent oroesophageal tube feeding based on WST. The outcomes were measured after 7 days of intervention, including the improvement of swallowing function assessment by WST, biochemical parameters, such as total serum protein, serum albumin, hemoglobin levels and body composition. This trial was registered with the Chinese Clinical Trial Registry, identifier ChiCTR 2100054054. Results: In total, 173 participants completed the study between September 1, 2020, and April 30, 2021. Patients receiving individualized nutritional support showed a more significant improvement in the total effective rate of swallowing function (95.3% vs. 85.1%, P < 0.05). After the intervention, the total serum protein level (0.97 ± 0.41 vs. -0.83 ± 0.47 g/L; P < 0.05), serum albumin level (0.33 ± 0.28 vs. -1.39 ± 0.36 g/L; P < 0.001) and lean tissue mass (0.13 ± 0.35 vs. -1.00 ± 0.40 g/L; P < 0.05) increased in the intervention group. The decrease of hemoglobin levels in the control group was more evident (-6.17 ± 1.63 vs. -0.64 ± 1.40 g/L; 95%CI, -9.78 to -1.28; P = 0.001). The difference of phase angle between the two groups was statistically significant (5.93 ± 0.88° vs. 5.77 ± 0.78°; P = 0.035), but not in body fat mass. Conclusions: In stroke patients with oropharyngeal dysphagia, the use of individualized nutritional support based on V-VST and intermittent oroesophageal tube feeding during the first week of hospitalization improved swallowing function and maintained nutritional status. Clinical Trial Registration: https://clinicaltrials.gov/, identifier: ChiCTR 2100054054.

Metabolic differences of two constructive species in saline-alkali grassland in China.

BACKGROUND: Salinization of soil is an urgent problem that restricts agroforestry production and environmental protection. Substantial accumulation of metal ions or highly alkaline soil alters plant metabolites and may even cause plant death. To explore the differences in the response strategies between Suaeda salsa (S. salsa) and Puccinellia tenuiflora (P. tenuiflora), two main constructive species that survive in saline-alkali soil, their metabolic differences were characterized. RESULT: Metabolomics was conducted to study the role of metabolic differences between S. salsa and P. tenuiflora under saline-alkali stress. A total of 68 significantly different metabolites were identified by GC-MS, including 9 sugars, 13 amino acids, 8 alcohols, and 34 acids. A more detailed analysis indicated that P. tenuiflora utilizes sugars more effectively and may be saline-alkali tolerant via sugar consumption, while S. salsa utilizes mainly amino acids, alcohols, and acids to resist saline-alkali stress. Measurement of phenolic compounds showed that more C6C3C6-compounds accumulated in P. tenuiflora, while more C6C1-compounds, phenolic compounds that can be used as signalling molecules to defend against stress, accumulated in S. salsa. CONCLUSIONS: Our observations suggest that S. salsa resists the toxicity of saline-alkali stress using aboveground organs and that P. tenuiflora eliminates this toxicity via roots. S. salsa has a stronger habitat transformation ability and can provide better habitat for other plants.

Ionomic and Metabolomic Analyses Reveal Different Response Mechanisms to Saline-Alkali Stress Between Suaeda salsa Community and Puccinellia tenuiflora Community.

Soil salinization imposes severe stress to plants, inhibits plant growth, and severely limits agricultural productivity and land utilization. The response of a single plant to saline-alkali stress has been well investigated. However, the plant community that usually works as a group to defend against saline-alkali stress was neglected. To determine the functions of plant community, in our current work, Suaeda salsa (S. salsa) community and Puccinellia tenuiflora (P. tenuiflora) community, two communities that are widely distributed in Hulun Buir Grassland in Northeastern China, were selected as research objects. Ionomic and metabolomic were applied to compare the differences between S. salsa community and P. tenuiflora community from the aspects of ion transport and phenolic compound accumulation, respectively. Ionomic studies demonstrated that many macroelements, including potassium (K) and calcium (Ca), were highly accumulated in S. salsa community whereas microelement manganese (Mn) was highly accumulated in P. tenuiflora community. In S. salsa community, transportation of K to aboveground parts of plants helps to maintain high K+ and low Na+ concentrations whereas the accumulation of Ca triggers the salt overly sensitive (SOS)-Na+ system to efflux Na+. In P. tenuiflora community, enrichment of Mn in roots elevates the level of Mn-superoxide dismutase (SOD) and increases the resistance to saline-alkali stress. Metabolomic studies revealed the high levels of C6C1-compounds and C6C3C6-compounds in S. salsa community and also the high levels of C6C3-compounds in P. tenuiflora community. C6C1-compounds function as signaling molecules to defend against stress and may stimulate the accumulation of C6C3C6-compounds. C6C3-compounds contribute to the elimination of free radicals and the maintenance of cell morphology. Collectively, our findings determine the abundance of phenolic compounds and various elements in S. salsa community and P. tenuiflora community in Hulun Buir Grassland and we explored different responses of S. salsa community and P. tenuiflora community to cope with saline-alkali stress. Understanding of plant response strategies from the perspective of community teamwork may provide a feasible and novel way to transform salinization land.

Investigation of bioactivities of Taxus chinensis, Taxus cuspidata, and Taxus × media by gas chromatography-mass spectrometry.

Taxus species have attracted much attention for their potency in cancer treatment. However, investigating the bioactivities of Taxus species is a complex task, due to their diversity, slow growth, and endangered state. The most important Taxus species in China are Taxus chinensis (T. chinensis), Taxus cuspidata (T. cuspidata), and Taxus × media (T. media), which mainly grow in the northeastern region. This article probes deep into the differences among the leaves of T. chinensis, T. cuspidata, and T. media, with the aid of gas chromatography-mass spectrometry (GC-MS). Through GC-MS, 162 compounds were detected in the samples and found to contain 35 bioactive metabolites. On this basis, 20 metabolites with significant bioactivities (antibiotic, antioxidant, anticancer, and antiaging effects) were identified via unsupervised learning of principal component analysis and supervised learning of partial least squares-discriminant analysis. The results show that T. media has the most prominent antibiotic, antioxidant, and anticancer effects, while T. cuspidata has the most diverse and abundant metabolites that slow down aging.