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1.
Orphanet J Rare Dis ; 19(1): 225, 2024 Jun 06.
Article in English | MEDLINE | ID: mdl-38844943

ABSTRACT

BACKGROUND: Infantile liver failure syndrome type 1 (ILFS1, OMIM #615,438), caused by leucyl-tRNA synthase 1 (LARS1, OMIM *151,350) deficiency, is a rare autosomal-recessive disorder. The clinical manifestations, molecular-genetic features, and prognosis of LARS1 disease remain largely elusive. METHODS: Three new instances of ILFS1 with confirmed variants in LARS1, encoding LARS1, were identified. Disease characteristics were summarized together with those of 33 reported cases. Kaplan-Meier analysis was performed to assess prognostic factors in ILFS1 patients. RESULTS: The 3 new ILFS1 patients harbored 6 novel variants in LARS1. Among the 36 known patients, 12 died or underwent liver transplantation. The main clinical features of ILFS1 were intrauterine growth restriction (31/32 patients in whom this finding was specifically described), failure to thrive (30/31), hypoalbuminemia (32/32), microcytic anemia (32/33), acute liver failure (24/34), neurodevelopmental delay (25/30), seizures (22/29), and muscular hypotonia (13/27). No significant correlations were observed between genotype and either presence of liver failure or clinical severity of disease. Kaplan-Meier analysis indicated that age of onset < 3mo (p = 0.0015, hazard ratio = 12.29, 95% confidence interval [CI] = 3.74-40.3), like liver failure (p = 0.0343, hazard ratio = 6.57, 95% CI = 1.96-22.0), conferred poor prognosis. CONCLUSIONS: Early age of presentation, like liver failure, confers poor prognosis in ILFS1. Genotype-phenotype correlations remain to be established.


Subject(s)
Liver Failure , Humans , Female , Male , Infant , Prognosis , Liver Failure/genetics , Liver Failure/pathology , Infant, Newborn , Liver Failure, Acute/genetics , Liver Failure, Acute/mortality
2.
J Pharm Pharmacol ; 2024 May 06.
Article in English | MEDLINE | ID: mdl-38708970

ABSTRACT

OBJECTIVES: Acute kidney injury (AKI) caused by cisplatin (CDDP) is a complex, critical illness with no effective or specific treatment. The purpose of the study was to assess the protective effect of protopanaxadiol (PPD) on the kidneys in CDDP-induced AKI models and its possible mechanisms. METHODS: In vitro, the protection of PPD was assessed in HK-2. KM mice were injected with CDDP to induce AKI models in vivo. The determination of blood urea nitrogen and serum creatinine (SCr) was performed, and pathological changes were examined by histopathological examination. Immunostaining and western blot analyses were used to analyze the expression levels of proteins. RESULTS: PPD can increase the viability of HK-2 cells damaged by CDDP, improve cell morphology, and alleviate the symptoms of AKI in mice. In addition, PPD can down-regulate the protein expression of TRF and up-regulate the protein expression of Ferritin heavy chain, Glutathione peroxidase 4, and ferroptosis suppressor protein 1 reduce the iron content in cells and kidney tissues, and restore the antioxidant defense system. CONCLUSION: PPD has an inhibitory effect on cisplatin-induced nephrotoxicity, which may be related to the inhibition of ferroptosis by regulating iron metabolism and lipid peroxidation.

3.
Article in English | MEDLINE | ID: mdl-38805336

ABSTRACT

Automated sleep staging is essential to assess sleep quality and treat sleep disorders, so the issue of electroencephalography (EEG)-based sleep staging has gained extensive research interests. However, the following difficulties exist in this issue: 1) how to effectively learn the intrinsic features of salient waves from single-channel EEG signals; 2) how to learn and capture the useful information of sleep stage transition rules; 3) how to address the class imbalance problem of sleep stages. To handle these problems in sleep staging, we propose a novel method named SleepFC. This method comprises convolutional feature pyramid network (CFPN), cross-scale temporal context learning (CSTCL), and class adaptive fine-tuning loss function (CAFTLF) based classification network. CFPN learns the multi-scale features from salient waves of EEG signals. CSTCL extracts the informative multi-scale transition rules between sleep stages. CAFTLF-based classification network handles the class imbalance problem. Extensive experiments on three public benchmark datasets demonstrate the superiority of SleepFC over the state-of-the-art approaches. Particularly, SleepFC has a significant performance advantage in recognizing the N1 sleep stage, which is challenging to distinguish.

4.
Phys Rev E ; 109(4-1): 044130, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38755836

ABSTRACT

We employ the eigen microstates approach to explore the self-organized criticality (SOC) in two celebrated sandpile models, namely the BTW model and the Manna model. In both models, phase transitions from the absorbing state to the critical state can be understood by the emergence of dominant eigen microstates with significantly increased weights. Spatial eigen microstates of avalanches can be uniformly characterized by a linear system size rescaling. The first temporal eigen microstates reveal scaling relations in both models. Furthermore, by finite-size scaling analysis of the first eigen microstates, we numerically estimate critical exponents, i.e., sqrt[σ_{0}w_{1}]/v[over ̃]_{1}∝L^{D} and v[over ̃]_{1}∝L^{D(1-τ_{s})/2}. Our findings could provide profound insights into eigen microstates of the universality and phase transition in nonequilibrium complex systems governed by self-organized criticality.

5.
Carbohydr Polym ; 336: 122104, 2024 Jul 15.
Article in English | MEDLINE | ID: mdl-38670774

ABSTRACT

Developing green and high-performance adsorbents to separate heavy metals from wastewater is a challenging task. Biomass hydrogel has the advantages of low cost, renewability, and biodegradability, but it has the problem of low adsorption efficiency. Herein, a novel chitosan/cellulose phosphonate composite hydrogel(CS/MCCP) is fabricated by two steps of reactions including the Phosphorylation reaction and the Mannich reaction. As an excellent chelating group, the phosphonate group greatly enhances the adsorption efficiency of the biomass hydrogel. The CS/MCCP shows ultrafast adsorption rate and excellent adsorption capacity for Pb(II) and Cu(II). The saturated adsorption capacity of Pb(II) and Cu(II) is 211.42 and 74.29 mg·g-1, respectively. The adsorption equilibration time is only 10 min. The adsorption performance of the CS/MCCP is superior to that of the reported cellulose/chitosan hydrogels. Besides, an in-depth analysis of the adsorption mechanism is conducted using X-ray photoelectron spectroscopy(XPS) combined with Density Functional Theory(DFT) calculation. The results reveal that the adsorption mechanism is electrostatic attraction and surface complexation, and there is a synergistic coordination between the phosphonate groups and the amino groups.

6.
Org Lett ; 26(16): 3447-3452, 2024 Apr 26.
Article in English | MEDLINE | ID: mdl-38602315

ABSTRACT

A method was developed for the enantioselective formal 1,2-diamination of disubstituted ketenes using iminosulfinamides as nitrogen sources. The protocol involves the addition of lithium iminosulfinamides to ketenes to form N-iminosulfinyl amide metalloenolates. These metalloenolates then undergo a [2,3]-sigmatropic rearrangement to yield unnatural α,α-disubstituted α-amino acid derivatives with high enantiopurity. The chirality present at the sulfur atom in the iminosulfinamides is effectively transferred to α carbon of the resulting products, facilitating the highly enantioselective amination of ketenes.

7.
J Org Chem ; 89(8): 5498-5510, 2024 Apr 19.
Article in English | MEDLINE | ID: mdl-38577943

ABSTRACT

Reactions allowing chemodivergence prove to be attractive strategies in synthetic organic chemistry. We herein described a highly practical, transition-metal-free, highly regioselective and chemodivergent cascade reaction controlled by fluorine sources, which involved a [3 + 2] cycloaddition or C-arylation process between aryne precursors and 3-aminomaleimides. These two pathways led to a wide scope of structurally diverse pyrrolo[3,4-b]indoles (19 examples) and 3-arylated maleimides (25 examples) in good-to-excellent yields. Furthermore, the reaction could be scaled up, and several synthetic transformations were accomplished for the preparation of functionalized molecules and might provide new opportunities for the discovery of N-heterocyclic drugs.

8.
Leuk Lymphoma ; : 1-11, 2024 Apr 10.
Article in English | MEDLINE | ID: mdl-38598516

ABSTRACT

Parsaclisib, a potent and highly selective phosphoinositide 3-kinase δ inhibitor, has shown clinical activity in relapsed/refractory (R/R) B-cell lymphoma. The phase 1 CITADEL-112 (NCT03424122) study assessed safety and efficacy of parsaclisib in combination with investigator choice standard of care (SOC; rituximab [Treatment A], rituximab plus bendamustine [Treatment B], or ibrutinib [Treatment C]) in 50 patients with R/R B-cell lymphoma. The most common treatment-emergent adverse events included neutropenia (62.5%, 50.0%, and 50.0% of patients in Treatments A, B, and C, respectively); diarrhea (37.5%) and anemia (31.3%) in Treatment A; abdominal pain, asthenia, diarrhea, and nausea (each 33.3%) in Treatment B; and increased alanine and aspartate aminotransferase (each 37.5%) in Treatment C. Objective responses were observed in 13 patients (81.3%) in Treatment A, 10 (55.6%) in Treatment B, and 8 (50.0%) in Treatment C. Parsaclisib combined with SOC therapies had an expected safety profile and promising efficacy in patients with R/R B-cell lymphomas.

9.
World J Gastrointest Oncol ; 16(3): 833-843, 2024 Mar 15.
Article in English | MEDLINE | ID: mdl-38577470

ABSTRACT

BACKGROUND: Traditional lymph node stage (N stage) has limitations in advanced gastric remnant cancer (GRC) patients; therefore, establishing a new predictive stage is necessary. AIM: To explore the predictive value of positive lymph node ratio (LNR) according to clinicopathological characteristics and prognosis of locally advanced GRC. METHODS: Seventy-four patients who underwent radical gastrectomy and lymphadenectomy for locally advanced GRC were retrospectively reviewed. The relationship between LNR and clinicopathological characteristics was analyzed. The survival analysis was performed using Kaplan-Meier survival curves and Cox regression model. RESULTS: Number of metastatic LNs, tumor diameter, depth of tumor invasion, Borrmann type, serum tumor biomarkers, and tumor-node-metastasis (TNM) stage were correlated with LNR stage and N stage. Univariate analysis revealed that the factors affecting survival included tumor diameter, anemia, serum tumor biomarkers, vascular or neural invasion, combined resection, LNR stage, N stage, and TNM stage (all P < 0.05). The median survival time for those with LNR0, LNR1, LNR2 and LNR3 stage were 61, 31, 23 and 17 mo, respectively, and the differences were significant (P = 0.000). Anemia, tumor biomarkers and LNR stage were independent prognostic factors for survival in multivariable analysis (all P < 0.05). CONCLUSION: The new LNR stage is uniquely based on number of metastatic LNs, with significant prognostic value for locally advanced GRC, and could better differentiate overall survival, compared with N stage.

10.
BMC Biotechnol ; 24(1): 15, 2024 Mar 23.
Article in English | MEDLINE | ID: mdl-38521922

ABSTRACT

BACKGROUND: Removal of heavy metals from water and soil is a pressing challenge in environmental engineering, and biosorption by microorganisms is considered as one of the most cost-effective methods. In this study, the metal-binding proteins MerR and ChrB derived from Cupriavidus metallidurans were separately expressed in Escherichia coli BL21 to construct adsorption strains. To improve the adsorption performance, surface display and codon optimization were carried out. RESULTS: In this study, we constructed 24 adsorption engineering strains for Hg2+ and Cr6+, utilizing different strategies. Among these engineering strains, the M'-002 and B-008 had the strongest heavy metal ion absorption ability. The M'-002 used the flexible linker and INPN to display the merRopt at the surface of the E. coli BL21, whose maximal adsorption capacity reached 658.40 µmol/g cell dry weight under concentrations of 300 µM Hg2+. And the B-008 overexpressed the chrB in the intracellular, its maximal capacity was 46.84 µmol/g cell dry weight under concentrations 500 µM Cr6+. While in the case of mixed ions solution (including Pb2+, Cd2+, Cr6+ and Hg2+), the total amount of ions adsorbed by M'-002 and B-008 showed an increase of up to 1.14- and 4.09-folds, compared to the capacities in the single ion solution. CONCLUSION: The construction and optimization of heavy metal adsorption strains were carried out in this work. A comparison of the adsorption behavior between single bacteria and mixed bacteria systems was investigated in both a single ion and a mixed ion environment. The Hg2+ absorption capacity is reached the highest reported to date with the engineered strain M'-002, which displayed the merRopt at the surface of chassis cell, indicating the strain's potential for its application in practical environments.


Subject(s)
Mercury , Metals, Heavy , Water Pollutants, Chemical , Adsorption , Carrier Proteins/metabolism , Escherichia coli/genetics , Escherichia coli/metabolism , Hydrogen-Ion Concentration , Ions/metabolism , Mercury/metabolism , Metals, Heavy/metabolism , Water Pollutants, Chemical/metabolism
11.
Front Endocrinol (Lausanne) ; 15: 1355703, 2024.
Article in English | MEDLINE | ID: mdl-38529391

ABSTRACT

Introduction: Polycystic ovary syndrome (PCOS) is the most common endocrinopathy affecting reproductive-aged women. Some retrospective studies with small sample sizes have reported that bariatric metabolic surgery is effective in remission of irregular menstruation in patients with PCOS and obesity. However, the correlation between preoperative body mass index (BMI), postoperative weight loss, and remission of irregular menstruation in patients with obesity and PCOS after sleeve gastrectomy (SG) is lack of consensus. Methods: We enrolled 229 participants with obesity and PCOS who underwent SG. All patients were followed up for one year after surgery. Remission of irregular menstruation was defined as a spontaneous consecutive six-month menstrual cycle in one year. Subgroup analysis was conducted using tertiles of preoperative BMI and postoperative total weight loss (TWL)% to determine their correlation with the remission of irregular menstruation after SG. Results: 79.03% (181/229) patients achieved remission of irregular menstruation one year after SG with a TWL% of 33.25 ± 0.46%. No significant difference was detected in the remission rate among the subgroups with different BMI (P=0.908). TWL% was correlated with the remission of irregular menstruation (OR 1.78, 95% CI 1.18-2.69, P<0.05). Conclusions: SG had a significant effect on the remission of irregular menstruation in patients with obesity and PCOS. Preoperative BMI did not emerge as a decisive factor correlated with remission; instead, TWL% showed potential as a key factor.


Subject(s)
Obesity, Morbid , Polycystic Ovary Syndrome , Humans , Female , Adult , Polycystic Ovary Syndrome/complications , Polycystic Ovary Syndrome/surgery , Body Mass Index , Obesity, Morbid/complications , Obesity, Morbid/surgery , Retrospective Studies , Treatment Outcome , Obesity/etiology , Menstruation Disturbances/etiology , Menstruation Disturbances/surgery , Gastrectomy , Weight Loss
12.
ACS Nano ; 18(12): 9114-9127, 2024 Mar 26.
Article in English | MEDLINE | ID: mdl-38477305

ABSTRACT

Immune checkpoint blockade (ICB) therapy is promising to revolutionize cancer regimens, but the low response rate and the lack of a suitable patient stratification method have impeded universal profit to cancer patients. Noninvasive positron emission tomography (PET) imaging in the whole body, upon coupling with specific biomarkers closely related to the immune response, could provide spatiotemporal information to prescribe cancer therapy. Herein, we demonstrate that antisilencing function 1a (ASF1a) could serve as a biomarker target to delineate tumor immune microenvironments by immune PET (iPET). The iPET radiotracer (68Ga-AP1) is designed to target ASF1a in tumors and predict immune response, and the signal intensity predicts anti-PD-1 (αPD-1) therapy response in a negative correlation manner. The ICB-resistant tumors with a high level of ASF1a as revealed by iPET (ASF1aHigh-iPET) are prescribed to be treated by either the combined 177Lu-labeled AP1 and αPD-1 or the standalone α particle-emitting 225Ac-labeled AP1, both achieving enhanced therapeutic efficacy and prolonged survival time. Our study not only replenishes the iPET arsenal for immune-related response evaluation by designing a reliable biomarker and a facile radiotracer but also provides optional therapeutic strategies for ICB-resistant tumors with versatile radionuclide-labeled AP1 peptides, which is promising for real-time clinical diagnosis and individualized therapy planning simultaneously.


Subject(s)
Neoplasms , Radioisotopes , Humans , Positron-Emission Tomography/methods , Biomarkers , Peptides , Neoplasms/diagnostic imaging , Neoplasms/drug therapy , Tumor Microenvironment
13.
J Nat Med ; 78(3): 474-487, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38431911

ABSTRACT

Lupus nephritis (LN) is a kidney disease that occurs after systemic lupus erythematosus (SLE) affects the kidneys. Pentraxin 3 (PTX3) is highly expressed in the serum of patients with LN. Renal PTX3 deposition is directly related to clinical symptoms such as proteinuria and inflammation. The excessive proliferation of mesangial cells (MCs) is one of the representative pathological changes in the progression of LN, which is closely related to its pathogenesis. Protopanaxadiol (PPD) is the main component of ginsenoside metabolism and has not been reported in LN. The aim of this study was to investigate the relationship between PTX3 and mesangial cell proliferation and to evaluate the potential role and mechanism of PPD in improving LN. PTX3 is highly expressed in the kidneys of LN patients and LN mice and is positively correlated with renal pathological indicators, including proteinuria and PCNA. The excessive expression of PTX3 facilitated the proliferation of MCs, facilitated the activation of the MAPK/ERK1/2 signaling pathway, and increased the expression of HIF-1α. Further studies showed that PPD can effectively inhibit the abnormal proliferation of MCs with high expression of PTX3 and significantly improve LN symptoms such as proteinuria in MRL/lpr mice. The mechanism may be related to the inhibition of the PTX3/MAPK/ERK1/2 pathway. In this study, both in vitro, in vivo, and clinical sample results show that PTX3 is involved in the regulation of MCs proliferation and the early occurrence of LN. Natural active compound PPD can improve LN by regulating the PTX3/MAPK/ERK1/2 pathway.


Subject(s)
C-Reactive Protein , Lupus Nephritis , MAP Kinase Signaling System , Sapogenins , Serum Amyloid P-Component , Lupus Nephritis/drug therapy , Lupus Nephritis/metabolism , Animals , Sapogenins/pharmacology , C-Reactive Protein/metabolism , Mice , Humans , MAP Kinase Signaling System/drug effects , Female , Serum Amyloid P-Component/metabolism , Cell Proliferation/drug effects , Adult , Male , Mice, Inbred MRL lpr , Kidney/drug effects , Kidney/metabolism , Kidney/pathology
15.
Heliyon ; 10(5): e26975, 2024 Mar 15.
Article in English | MEDLINE | ID: mdl-38468925

ABSTRACT

Purpose: One of the best anticancer treatments available is radiotherapy, which can be used either alone or in conjunction with other forms of treatment including chemotherapy and surgery. Nevertheless, a number of biochemical and physiological processes that react to ionizing radiation might provide tumor cells radioresistance, which makes radiotherapy ineffective. It has been found that CDKN1A regulates DNA damage repair, which contributes to tumor radioresistance. However, the precise mechanism is still unknown. Therefore, this study aimed to explore the mechanisms underlying CDKN1A-enhanced radioresistance in tumor cells. Methods: Cells were irradiated with 4 Gy after CDKN1A overexpression or knockdown. CDKN1A expression was measured using real-time PCR, cell viability was evaluated using cell counting kit-8 and colony formation assays, and cytotoxicity was assessed using a lactate dehydrogenase assay. Pyroptosis in cells was analyzed using caspase-1 activity assay, enzyme-linked immunosorbent assay, and flow cytometry. Inflammation activation was detected through a co-immunoprecipitation assay. Activation of pyroptosis-related proteins was analyzed using immunohistochemistry, Western blot, and immunofluorescence. Tumor radioresistance in vivo was evaluated in a mouse xenograft model. Results: Radiotherapy upregulated CDKN1A expression, which promoted lung adenocarcinoma cell survival. CDKN1A influenced radiation-induced pyroptosis in A549, which mainly depended on inhibiting the activation of the AIM2 inflammasome by promoting DNA repair. Additionally, CDKN1A upregulation enhanced A549 xenograft tumor radioresistance by inhibiting radiation-induced pyroptosis in vivo. Conclusions: CDKN1A inhibits pyroptosis to enhance the radioresistance of lung adenocarcinoma cells by promoting DNA repair. This study may serve as a reference for developing novel targeted therapies against cancer.

16.
Adv Sci (Weinh) ; 11(18): e2400845, 2024 May.
Article in English | MEDLINE | ID: mdl-38520732

ABSTRACT

Complete remission of colorectal cancer (CRC) is still unachievable in the majority of patients by common fractionated radiotherapy, leaving risks of tumor metastasis and recurrence. Herein, clinical CRC samples demonstrated a difference in the phosphorylation of translation initiation factor eIF2α (p-eIF2α) and the activating transcription factor 4 (ATF4), whose increased expression by initial X-ray irradiation led to the resistance to subsequent radiotherapy. The underlying mechanism is studied in radio-resistant CT26 cells, revealing that the incomplete mitochondrial outer membrane permeabilization (iMOMP) triggered by X-ray irradiation is key for the elevated expression of p-eIF2α and ATF4, and therefore radio-resistance. This finding guided to discover that metformin and 2-DG are synergistic in reversing radio resistance by inhibiting p-eIF2α and ATF4. Liposomes loaded with metformin and 2-DG (M/D-Lipo) are thus prepared for enhancing fractionated radiotherapy of CRC, which achieved satisfactory therapeutic efficacy in both local and metastatic CRC tumors by reversing radio-resistance and preventing T lymphocyte exhaustion.


Subject(s)
Colorectal Neoplasms , Liposomes , Metformin , Mitochondria , Radiation Tolerance , Colorectal Neoplasms/metabolism , Colorectal Neoplasms/radiotherapy , Colorectal Neoplasms/pathology , Mice , Animals , Humans , Mitochondria/metabolism , Mitochondria/drug effects , Mitochondria/radiation effects , Metformin/pharmacology , Metformin/therapeutic use , Radiation Tolerance/drug effects , Cell Line, Tumor , Disease Models, Animal , Activating Transcription Factor 4/metabolism , Activating Transcription Factor 4/genetics
17.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 41(1): 160-167, 2024 Feb 25.
Article in Chinese | MEDLINE | ID: mdl-38403617

ABSTRACT

Assisting immobile individuals with regular repositioning to adjust pressure distribution on key prominences such as the back and buttocks is the most effective measure for preventing pressure ulcers. However, compared to active self-repositioning, passive assisted repositioning results in distinct variations in force distribution on different body parts. This incongruity can affect the comfort of repositioning and potentially lead to a risk of secondary injury, for certain trauma or critically ill patients. Therefore, it is of considerable practical importance to study the passive turning comfort and the optimal turning strategy. Initially, in this study, the load-bearing characteristics of various joints during passive repositioning were examined, and a wedge-shaped airbag configuration was proposed. The airbags coupled layout on the mattress was equivalently represented as a spring-damping system, with essential model parameters determined using experimental techniques. Subsequently, different assisted repositioning strategies were devised by adjusting force application positions and sequences. A human-mattress force-coupled simulation model was developed based on rigid human body structure and equivalent flexible springs. This model provided the force distribution across the primary pressure points on the human body. Finally, assisted repositioning experiments were conducted with 15 participants. The passive repositioning effectiveness and pressure redistribution was validated based on the simulation results, experimental data, and questionnaire responses. Furthermore, the mechanical factors influencing comfort during passive assisted repositioning were elucidated, providing a theoretical foundation for subsequent mattress design and optimization of repositioning strategies.


Subject(s)
Pressure Ulcer , Humans , Pressure Ulcer/prevention & control , Beds
18.
Zhongguo Zhong Yao Za Zhi ; 49(2): 354-360, 2024 Jan.
Article in Chinese | MEDLINE | ID: mdl-38403311

ABSTRACT

This study aimed to examine the morphological, physiological, and biochemical alterations occurring in Notopterygium incisum seeds throughout their developmental stages, with the objective of establishing a theoretical foundation for the cultivation of superior quality seeds. The experimental materials utilized in this study were the seeds of N. incisum at various stages of development following anthesis. Through the employment of morphological observation and plant physiology techniques, the external morphology, nutrients, enzyme activity, and endogenous hormones of the seeds were assessed. The results revealed a transition in seed coat color from light green to brown during the growth and development of N. incisum seeds. Additionally, as the seeds matured, a decrease in water content was observed. Conversely, starch content exhibited a progressive increase, while sucrose content displayed fluctuations. At 7 days after anthesis, the soluble sugar content attained its highest level of 4.52 mg·g~(-1), whereas the soluble protein content reached its maximum of 6.00 mg·g~(-1) at 14 days after anthesis and its minimum of 4.94 mg·g~(-1) at 42 days after anthesis. The activity of superoxide dismutase(SOD) exhibited an initial increase, followed by a decrease, and eventually reached a stable state. Conversely, the activities of catalase(CAT) and peroxidase(POD) demonstrated a decrease initially, followed by an increase, and then another decrease. The levels of the four endogenous hormones, namely gibberellin(GA_3), zeatin riboside(ZR), auxin(IAA), and abscisic acid(ABA), in the seeds displayed significant variations, with IAA and ABA exhibiting considerably higher levels compared to the other hormones. The levels of plant growth-promoting hormones, represented by IAA, generally displayed a pattern of initial increase followed by a subsequent decrease during seed development, while the plant growth-inhibiting hormone ABA showed the opposite trend. The findings indicate that the alterations in nutrient composition, antioxidant enzyme activity, and endogenous hormone levels vary throughout the maturation process of N. incisum seeds. These observations hold relevance for the cultivation of N. incisum seeds.


Subject(s)
Gibberellins , Plant Growth Regulators , Abscisic Acid , Seeds , Hormones/metabolism , Germination/physiology
19.
Pest Manag Sci ; 80(6): 2817-2826, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38323798

ABSTRACT

BACKGROUND: Machine vision-based precision weed management is a promising solution to substantially reduce herbicide input and weed control cost. The objective of this research was to compare two different deep learning-based approaches for detecting weeds in cabbage: (1) detecting weeds directly, and (2) detecting crops by generating the bounding boxes covering the crops and any green pixels outside the bounding boxes were deemed as weeds. RESULTS: The precision, recall, F1-score, mAP0.5, mAP0.5:0.95 of You Only Look Once (YOLO) v5 for detecting cabbage were 0.986, 0.979, 0.982, 0.995, and 0.851, respectively, while these metrics were 0.973, 0.985, 0.979, 0.993, and 0.906 for YOLOv8, respectively. However, none of these metrics exceeded 0.891 when detecting weeds. The reduced performances for directly detecting weeds could be attributed to the diverse weed species at varying densities and growth stages with different plant morphologies. A segmentation procedure demonstrated its effectiveness for extracting weeds outside the bounding boxes covering the crops, and thereby realizing effective indirect weed detection. CONCLUSION: The indirect weed detection approach demands less manpower as the need for constructing a large training dataset containing a variety of weed species is unnecessary. However, in a certain case, weeds are likely to remain undetected due to their growth in close proximity with crops and being situated within the predicted bounding boxes that encompass the crops. The models generated in this research can be used in conjunction with the machine vision subsystem of a smart sprayer or mechanical weeder. © 2024 Society of Chemical Industry.


Subject(s)
Brassica , Deep Learning , Plant Weeds , Weed Control , Brassica/growth & development , Plant Weeds/growth & development , Weed Control/methods , Crops, Agricultural/growth & development
20.
Chem Sci ; 15(6): 2236-2242, 2024 Feb 07.
Article in English | MEDLINE | ID: mdl-38332812

ABSTRACT

Unprecedented regioselective trans-hydroboration and carboboration of unbiased electronically internal alkynes were realized via a nickel catalysis system with the aid of the directing group strategy. Furthermore, the excellent α- and ß-regioselectivity could be accurately switched by the nitrogen ligand (terpy) and phosphine ligand (Xantphos). Mechanistic studies provided an insight into the rational reaction process, that underwent the cis-to-trans isomerization of alkenyl nickel species. This transformation not only expands the scope of transition-metal-catalyzed boration of internal alkynes but also, more particularly, portrays the vast prospects of the directing group strategy in the selective functionalization of unactivated alkynes.

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