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1.
J Environ Manage ; 359: 121069, 2024 May.
Article in English | MEDLINE | ID: mdl-38714034

ABSTRACT

The traditional classification of drought events into seasonal and flash types oversimplified the complexity and variability of global drought phenomena, limiting a deeper understanding of drought characteristics and their impacts on vegetation. To address this issue, soil moisture percentile methods and the Soil Moisture Anomaly Percentage Index (SMAPI) were employed to create time series for flash drought (FD) and seasonal drought (SD) events globally from 1981 to 2020. A novel categorization framework was proposed to subdivide the two basic drought categories into eight distinct drought types using a set relationship identification method. The results showed fluctuating trends in the frequencies of Independent FD and Inclusion FD, which declined rapidly after 2011 at rates of 0.05 and 0.04 times/year, respectively. Independent FD frequency was highest in humid areas and decreased with increasing aridity. The spatial distributions of Inclusion FD and SD were similar, with both frequencies highest in extremely arid areas and decreasing with increasing humidity. The frequency of Independent SD, which peaked in semi-arid areas, increased significantly after 2011 at a rate of 0.01 times/year. The occurrence of FD evolving into SD or emerging at the end of SD was rare, with a global average of 0.46 events/decade and little spatial variation. Between 1981 and 2020, FD showed a U-shaped trend in drought duration, while SD showed no clear pattern. The duration of FD showed little difference across arid and humid zones, but the duration of SD decreased significantly with increasing humidity. Vegetation responses to drought varied, with arid regions showing longer response time compared to humid regions. A positive correlation between temperature and solar-induced chlorophyll fluorescence (SIF) during droughts was observed, while precipitation generally showed a negative correlation with SIF. Radiation had a minimal effect on SIF during droughts. The study offered a comprehensive categorization of drought events, enhancing our understanding of their spatiotemporal characteristics and vegetation responses on a global scale.


Subject(s)
Droughts , Seasons , Soil , Plants
2.
Nat Prod Res ; : 1-11, 2024 Mar 18.
Article in English | MEDLINE | ID: mdl-38498767

ABSTRACT

The chemical investigation of the fibrous roots of Ophiopogon japonicus afforded two new steroidal saponins, named ophiojaponin F (1) and ophiojaponin G (2), together with twelve known steroidal saponins (3-14) and ten known homoisoflavonoids (15-24). The structures of the isolated compounds were established unambiguously via spectroscopic analyses (NMR and HR-ESI-MS). Ophiojaponin F (1) is a 23-hydroxylated spirostanol saponin, and this type of steroidal saponin rarely been reported in liriopogons. All isolates were evaluated for their anti-pulmonary fibrosis activities on TGF-ß1-actived NIH3T3 cells for the first time. Among them, compounds 3, 4, 11-13, 15-19, 21 and 24 showed potential anti-pulmonary fibrosis effects with IC50 values ranging from 3.61 ± 0.86 µM to 21.33 ± 1.82 µM, and the main component ophiopogonin D (4) displayed the best activity with an IC50 value of 3.61 ± 0.86 µM. Thus, ophiopogonin D may be a potent candidate for the treatment of pulmonary fibrosis.

3.
Biomimetics (Basel) ; 8(4)2023 Aug 14.
Article in English | MEDLINE | ID: mdl-37622969

ABSTRACT

Locomotion and manipulation are two essential skills in robotics but are often divided or decoupled into two separate problems. It is widely accepted that the topological duality between multi-legged locomotion and multi-fingered manipulation shares an intrinsic model. However, a lack of research remains to identify the data-driven evidence for further research. This paper explores a unified formulation of the loco-manipulation problem using reinforcement learning (RL) by reconfiguring robotic limbs with an overconstrained design into multi-legged and multi-fingered robots. Such design reconfiguration allows for adopting a co-training architecture for reinforcement learning towards a unified loco-manipulation policy. As a result, we find data-driven evidence to support the transferability between locomotion and manipulation skills using a single RL policy with a multilayer perceptron or graph neural network. We also demonstrate the Sim2Real transfer of the learned loco-manipulation skills in a robotic prototype. This work expands the knowledge frontiers on loco-manipulation transferability with learning-based evidence applied in a novel platform with overconstrained robotic limbs.

4.
Environ Res ; 232: 116359, 2023 Sep 01.
Article in English | MEDLINE | ID: mdl-37295585

ABSTRACT

The determination of critical management areas for nitrogen (N) and phosphorus (P) losses in large-scale basins is critical to reduce costs and improve efficiency. In this study, the spatial and temporal characteristics of the N and P losses in the Jialing River from 2000 to 2019 were calculated based on the Soil and Water Assessment Tool (SWAT) model. The trends were analyzed using the Theil-Sen median analysis and Mann-Kendall test. The Getis-Ord Gi* was used to determine significant coldspot and hotspot regions to identify critical regions and priorities for regional management. The ranges of the annual average unit load losses for N and P in the Jialing River were 1.21-54.53 kg ha-1 and 0.05-1.35 kg ha-1, respectively. The interannual variations in both N and P losses showed decreasing trends, with change rates of 0.327 and 0.003 kg ha-1·a-1 and change magnitudes of 50.96% and 41.05%, respectively. N and P losses were highest in the summer and lowest in the winter. The coldspot regions for N loss were clustered northwest of the upstream Jialing River and north of Fujiang River. The coldspot regions for P loss were clustered in the central, western, and northern areas of the upstream Jialing River. The above regions were found to be not critical for management. The hotspot regions for N loss were clustered in the south of the upstream Jialing River, the central-western and southern areas of the Fujiang River, and the central area of the Qujiang River. The hotspot regions for P loss were clustered in the south-central area of the upstream Jialing River, the southern and northern areas of the middle and downstream Jialing River, the western and southern areas of the Fujiang River, and the southern area of the Qujiang River. The above regions were found to be critical for management. There was a significant difference between the high load area for N and the hotspot regions, while the high load region for P was consistent with the hotspot regions. The coldspot and hotspot regions for N would change locally in spring and winter, and the coldspot and hotspot regions for P would change locally in summer and winter, respectively. Therefore, managers should make specific adjustments in critical regions for different pollutants according to seasonal characteristics when developing management programs.


Subject(s)
Phosphorus , Water Pollutants, Chemical , Phosphorus/analysis , Nitrogen/analysis , Rivers , Water Pollutants, Chemical/analysis , Seasons , China , Environmental Monitoring
5.
J Org Chem ; 88(13): 9332-9342, 2023 Jul 07.
Article in English | MEDLINE | ID: mdl-37347936

ABSTRACT

Pudovik addition/[1,2]-phospha-Brook rearrangement as an efficient tool for generation of anionic nucleophiles is an attractive strategy for the construction of C-C bonds in organic synthesis. Herein, we report organocatalytic 1,6-conjugate addition of para-quinone methides utilizing Pudovik addition/[1,2]-phospha-Brook rearrangement. Chiral guanidine-sulfonamide catalyzed the three-component reaction efficiently, providing biologically active oxindole/biaryl/phosphorus-based structures in high yields with excellent diastereo- and enantioselectivities. A possible bifunctional catalytic mode was proposed to elucidate the chiral control of this process.


Subject(s)
Benzoquinones , Catalysis , Guanidine
6.
J Ginseng Res ; 46(5): 636-645, 2022 Sep.
Article in English | MEDLINE | ID: mdl-36090681

ABSTRACT

Background: Ginsenoside Rg3 and gemcitabine have mutual enhancing antitumor effects. However, the underlying mechanisms are not clear. This study explored the influence of ginsenoside Rg3 on Zinc finger protein 91 homolog (ZFP91) expression in pancreatic adenocarcinoma (PAAD) and their regulatory mechanisms on gemcitabine sensitivity. Methods: RNA-seq and survival data from The Cancer Genome Atlas (TCGA)-PAAD and Genotype-Tissue Expression (GTEx) were used for in-silicon analysis. PANC-1, BxPC-3, and PANC-1 gemcitabine-resistant (PANC-1/GR) cells were used for in vitro analysis. PANC-1 derived tumor xenograft nude mice model was used to assess the influence of ginsenoside Rg3 and ZFP91 on tumor growth in vivo. Results: Ginsenoside Rg3 reduced ZFP91 expression in PAAD cells in a dose-dependent manner. ZFP91 upregulation was associated with significantly shorter survival of patients with PAAD. ZFP91 overexpression induced gemcitabine resistance, which was partly conquered by ginsenoside Rg3 treatment. ZFP91 depletion sensitized PANC-1/GR cells to gemcitabine treatment. ZFP91 interacted with Testis-Specific Y-Encoded-Like Protein 2 (TSPYL2), induced its poly-ubiquitination, and promoted proteasomal degradation. Ginsenoside Rg3 treatment weakened ZFP91-induced TSPYL2 poly-ubiquitination and degradation. Enforced TSPYL2 expression increased gemcitabine sensitivity of PAAD cells and partly reversed induced gemcitabine resistance in PANC-1/GR cells. Conclusion: Ginsenoside Rg3 can increase gemcitabine sensitivity of pancreatic adenocarcinoma at least via reducing ZFP91 mediated TSPYL2 destabilization.

7.
J Ginseng Res ; 45(6): 734-743, 2021 Nov.
Article in English | MEDLINE | ID: mdl-34764728

ABSTRACT

BACKGROUND: The underlying mechanisms of the potential tumor-suppressive effects of ginsenoside Rh2 are complex. N6-methyladenosine (m6A) RNA methylation is usually dysregulated in cancer. This study explored the regulatory effect of ginsenoside Rh2 on m6A RNA methylation in cancer.Methods: m6A RNA quantification and gene-specific m6A RIP-qPCR assays were applied to assess total and gene-specific m6A RNA levels. Co-immunoprecipitation, fractionation western blotting, and immunofluorescence staining were performed to detect protein interactions and distribution. QRT-PCR, dual-luciferase, and ChIP-qPCR assays were conducted to check the transcriptional regulation. RESULTS: Ginsenoside Rh2 reduces m6A RNA methylation and KIF26B expression in a dose-dependent manner in some cancers. KIF26B interacts with ZC3H13 and CBLL1 in the cytoplasm of cancer cells and enhances their nuclear distribution. KIF26B inhibition reduces m6A RNA methylation level in cancer cells. SRF bound to the KIF26B promoter and activated its transcription. SRF mRNA m6A abundance significantly decreased upon KIF26B silencing. SRF knockdown suppressed cancer cell proliferation and growth both in vitro and in vivo, the effect of which was partly rescued by KIF26B overexpression.Conclusion: ginsenoside Rh2 reduces m6A RNA methylation via downregulating KIF26B expression in some cancer cells. KIF26B elevates m6A RNA methylation via enhancing ZC3H13/CBLL1 nuclear localization. KIF26B-SRF forms a positive feedback loop facilitating tumor growth.

8.
J Environ Pathol Toxicol Oncol ; 40(3): 51-61, 2021.
Article in English | MEDLINE | ID: mdl-34587404

ABSTRACT

AIM: To investigate the anticancer mechanism of neferine on DMBA-prompted mammary tumorigenesis in animals. METHODS: Mammary cancer was prompted by the subcutaneous injection of 25 mg DMBA mixed in 1 ml of the vehicle (sunflower oil [0.5 ml] and saline [0.5 ml]). We analyzed the biochemical and molecular expression of cell-proliferation and apoptotic markers in normal and DMBA-induced rats. RESULTS: We detected low body weight, elevated quantities of lipid peroxidation, and low antioxidant enzyme activities in mammary tissues of DMBA-induced animals. We also found an invasive ductal carcinoma in DMBA-induced animals by histopathological assessment. Furthermore, western blotting findings displayed an augmented expression of PI3K, AKT, NF-κB, PCNA, cyclin D1, Ki-67, and Bcl-2, while reducing expression of p53, Bax, caspase-3, and caspase-9 in DMBA-induced cancer-bearing animals. RT-PCR results found upregulation of cyclin D1, PCNA, and Ki-67, and reduced expression of p53 in DMBA-prompted animals. The oral administration of neferine effectually inhibited mammary tumors via improved antioxidants and prevented lipid peroxidation activities when compared with tumor-bearing rats. Furthermore, neferine also modulated PI3K/AKT/NF-κB signaling through inhibiting cell proliferation and induced apoptosis in tumor-bearing rats. CONCLUSION: In our findings, we concluded that neferine has an anti-proliferative and enhancing apoptotic property against DMBA-induced mammary cancer.


Subject(s)
Antineoplastic Agents, Phytogenic/pharmacology , Apoptosis/drug effects , Benzylisoquinolines/pharmacology , Mammary Neoplasms, Experimental/drug therapy , 9,10-Dimethyl-1,2-benzanthracene/toxicity , Animals , Apoptosis/physiology , Body Weight/drug effects , Carcinogens/toxicity , Cell Proliferation/drug effects , Cell Proliferation/physiology , Female , Gene Expression Regulation, Neoplastic/drug effects , Lipid Peroxidation/drug effects , Mammary Neoplasms, Experimental/chemically induced , Mammary Neoplasms, Experimental/metabolism , Mammary Neoplasms, Experimental/pathology , NF-kappa B/metabolism , Phosphatidylinositol 3-Kinases/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Rats , Signal Transduction/drug effects
9.
Nat Cancer ; 2(4): 457-473, 2021 04.
Article in English | MEDLINE | ID: mdl-35122000

ABSTRACT

Although chemotherapy can stimulate antitumor immunity by inducing interferon (IFN) response, the functional role of tumor-associated macrophages in this scenario remains unclear. Here, we found that IFN-activated proinflammatory macrophages after neoadjuvant chemotherapy enhanced antitumor immunity but promoted cancer chemoresistance. Mechanistically, IFN induced expression of cytoplasmic long noncoding RNA IFN-responsive nuclear factor-κB activator (IRENA) in macrophages, which triggered nuclear factor-κB signaling via dimerizing protein kinase R and subsequently increased production of protumor inflammatory cytokines. By constructing macrophage-conditional IRENA-knockout mice, we found that targeting IRENA in IFN-activated macrophages abrogated their protumor effects, while retaining their capacity to enhance antitumor immunity. Clinically, IRENA expression in post-chemotherapy macrophages was associated with poor patient survival. These findings indicate that lncRNA can determine the dichotomy of inflammatory cells on cancer progression and antitumor immunity and suggest that targeting IRENA is an effective therapeutic strategy to reversing tumor-promoting inflammation.


Subject(s)
Breast Neoplasms , RNA, Long Noncoding , Animals , Breast Neoplasms/drug therapy , Female , Humans , Macrophages , Mice , NF-kappa B/genetics , Phenotype , RNA, Long Noncoding/genetics
10.
J Environ Qual ; 49(1): 220-227, 2020 Jan.
Article in English | MEDLINE | ID: mdl-33016352

ABSTRACT

The economic viability of corn biorefineries depends heavily on the sale of coproducts as animal feeds, but elevated phosphorus (P) contents can exacerbate manure management issues. Phosphorus removal from light steep water and thin stillage, two concentrated in-process aqueous streams at wet milling and dry-grind corn biorefineries, could simultaneously generate concentrated fertilizer and low-P animal feeds, but little is known regarding how differences in stream composition affect removal. To address this data gap, we show that the solubility of P in light steep filtrate (LSF) and thin stillage filtrate (TSF) exhibits distinct sensitivity to calcium (Ca) and base addition due to differences in P fractionation and protein abundance. In LSF, P was primarily organic, and near-complete removal of P (96%) was observed at pH 8 and a Ca/total P (TP) ratio of 2. In TSF, TP removal was lower (81%), and there was more equal distribution of organic and orthophosphate, indicating that the Ca requirements of inorganic P precipitation were a limiting factor. The C/H/N ratio, elemental characterization, and crude protein analysis of the precipitated solids indicated that coprecipitation of amorphous solids containing Ca, Mg, and K with soluble proteins facilitated removal of P, particularly in LSF. Although the removal mechanisms and solubility limits differed, these results highlighted the magnitude (40-70 mM) and efficacy (80-96%) of P recovery from two biorefinery streams.


Subject(s)
Phosphorus , Zea mays , Animal Feed , Animals , Chemical Fractionation , Water
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