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1.
BMC Plant Biol ; 24(1): 97, 2024 Feb 09.
Article in English | MEDLINE | ID: mdl-38331770

ABSTRACT

BACKGROUND: Drought is thought to be a major abiotic stress that dramatically limits tomato growth and production. As signal molecule, melatonin (MT) and carbon monoxide (CO) can enhance plant stress resistance. However, the effect and underlying mechanism of CO involving MT-mediated drought resistance in seedling growth remains unknown. In this study, tomato (Solanum lycopersicum L. 'Micro-Tom') seedlings were used to investigate the interaction and mechanism of MT and CO in response to drought stress. RESULTS: The growth of tomato seedlings was inhibited significantly under drought stress. Exogenous MT or CO mitigated the drought-induced impairment in a dose-dependent manner, with the greatest efficiency provided by 100 and 500 µM, respectively. But application of hemoglobin (Hb, a CO scavenger) restrained the positive effects of MT on the growth of tomato seedlings under drought stress. MT and CO treatment promoted chlorophyll a (Chl a) and chlorophyll a (Chl b) accumulations. Under drought stress, the intermediate products of chlorophyll biosynthesis such as protoporphyrin IX (Proto IX), Mg-protoporphyrin IX (Mg-Proto IX), potochlorophyllide (Pchlide) and heme were increased by MT or CO, but uroporphyrinogen III (Uro III) content decreased in MT-treated or CO-treated tomato seedlings. Meanwhile, MT or CO up-regulated the expression of chlorophyll and heme synthetic-related genes SlUROD, SlPPOX, SlMGMT, SlFECH, SlPOR, SlChlS, and SlCAO. However, the effects of MT on chlorophyll biosynthesis were almost reversed by Hb. CONCLUSION: The results suggested that MT and CO can alleviate drought stress and facilitate the synthesis of Chl and heme in tomato seedlings. CO played an essential role in MT-enhanced drought resistance via facilitating chlorophyll biosynthesis pathway.


Subject(s)
Melatonin , Solanum lycopersicum , Chlorophyll/metabolism , Melatonin/metabolism , Seedlings/metabolism , Solanum lycopersicum/genetics , Chlorophyll A/metabolism , Carbon Monoxide/metabolism , Carbon Monoxide/pharmacology , Drought Resistance , Heme/metabolism , Heme/pharmacology
2.
Physiol Plant ; 176(4): e14419, 2024.
Article in English | MEDLINE | ID: mdl-38973451

ABSTRACT

Abiotic stress impairs plant growth and development, thereby causing low yield and inferior quality of crops. Increasing studies reported that strigolactones (SL) are plant hormones that enhance plant stress resistance by regulating plant physiological processes and gene expressions. In this review, we introduce the response and regulatory role of SL in salt, drought, light, heat, cold and cadmium stresses in plants. This review also discusses how SL alleviate the damage of abiotic stress in plants, furthermore, introducing the mechanisms of SL enhancing plant stress resistance at the genetic level. Under abiotic stress, the exogenous SL analog GR24 can induce the biosynthesis of SL in plants, and endogenous SL can alleviate the damage caused by abiotic stress. SL enhanced the stress resistance of plants by protecting photosynthesis, enhancing the antioxidant capacity of plants and promoting the symbiosis between plants and arbuscular mycorrhiza (AM). SL interact with abscisic acid (ABA), salicylic acid (SA), auxin, cytokinin (CK), jasmonic acid (JA), hydrogen peroxide (H2O2) and other signal molecules to jointly regulate plant stress resistance. Lastly, both the importance of SL and their challenges for future work are outlined in order to further elucidate the specific mechanisms underlying the roles of SL in plant responses to abiotic stress.


Subject(s)
Lactones , Plant Growth Regulators , Stress, Physiological , Lactones/metabolism , Plant Growth Regulators/metabolism , Plants/metabolism , Plants/drug effects , Plants/genetics , Gene Expression Regulation, Plant/drug effects
3.
Plant Cell Rep ; 43(7): 180, 2024 Jun 24.
Article in English | MEDLINE | ID: mdl-38914787

ABSTRACT

KEY MESSAGE: Hydrogen sulfide improved cold resistance of tomato fruits by regulating energy metabolism and delaying cell wall degradation, thereby alleviating the damage of cold storage on fruits. Postharvest cold storage in tomato fruits extended shelf life but caused the appearance of chilling injury (CI), appeared by softness and spots on the surface of the fruits. These changes were linked closely with energy and cell wall metabolisms. Hydrogen sulfide (H2S), as the gaseous fresh-keeping regulator, was used in the present study to investigate the effects of H2S on energy and cell wall metabolisms in tomato fruits during cold storage. Fruits after harvest were fumigated with different concentrations (0, 0.5, 1, 1.5 mM) of sodium hydrosulfide (NaHS) solution as H2S honor for 24 h and stored at 4 °C for 25 days. The results showed that 1 and 1.5 mM NaHS solution fumigation promoted the accumulation of endogenous H2S, followed by the increase in L-cysteine desulfurase (LCD) and D-cysteine desulfurase (DCD) activities in fruits during cold storage. It was also found that 1 and 1.5 mM NaHS treatments improved H+-ATPase, Ca2+-ATPase, cytochrome C oxidase (CCO), and succinic dehydrogenase (SDH) activities. Moreover, the contents of cellulose and hemicellulose were increased by 1 and 1.5 mM NaHS, following down-regulated activities of cellulase (CL), pectin lyase (PL), α-mannosidase (α-man) and ß-Galactosidase (ß-Gal) and down-regulated expression of PL1, PL8, MAN4 and MAN7 genes. Thus, H2S alleviates CI led by cold storage in tomato fruits via regulating energy and cell wall metabolisms.


Subject(s)
Cell Wall , Cold Temperature , Energy Metabolism , Fruit , Hydrogen Sulfide , Solanum lycopersicum , Cell Wall/metabolism , Hydrogen Sulfide/pharmacology , Hydrogen Sulfide/metabolism , Solanum lycopersicum/genetics , Solanum lycopersicum/metabolism , Solanum lycopersicum/physiology , Fruit/metabolism , Fruit/genetics , Fruit/drug effects , Energy Metabolism/drug effects , Gene Expression Regulation, Plant/drug effects , Plant Proteins/metabolism , Plant Proteins/genetics , Food Storage/methods , Sulfides/pharmacology , Sulfides/metabolism
4.
BMC Pregnancy Childbirth ; 24(1): 255, 2024 Apr 08.
Article in English | MEDLINE | ID: mdl-38589817

ABSTRACT

BACKGROUND: Uterine rupture in pregnant women can lead to serious adverse outcomes. This study aimed to explore the clinical characteristics, treatment, and prognosis of patients with complete uterine rupture. METHODS: Data from 33 cases of surgically confirmed complete uterine rupture at Chenzhou No.1 People's Hospital between January 2015 and December 2022 were analyzed retrospectively. RESULTS: In total, 31,555 pregnant women delivered in our hospital during the study period. Of these, approximately 1‰ (n = 33) had complete uterine rupture. The average gestational age at complete uterine rupture was 31+4 weeks (13+1-40+3 weeks), and the average bleeding volume was 1896.97 ml (200-6000 ml). Twenty-six patients (78.79%) had undergone more than two deliveries. Twenty-five women (75.76%) experienced uterine rupture after a cesarean section, two (6.06%) after fallopian tube surgery, one (3.03%) after laparoscopic cervical cerclage, and one (3.03%) after wedge resection of the uterine horn, and Fifteen women (45.45%) presented with uterine rupture at the original cesarean section incision scar. Thirteen patients (39.39%) were transferred to our hospital after their initial diagnosis. Seven patients (21.21%) had no obvious symptoms, and only four patients (12.12%) had typical persistent lower abdominal pain. There were 13 cases (39.39%, including eight cases ≥ 28 weeks old) of fetal death in utero and two cases (6.06%, both full term) of severe neonatal asphyxia. The rates of postpartum hemorrhage, blood transfusion, hysterectomy were 66.67%, 63.64%, and 21.21%. Maternal death occurred in one case (3.03%). CONCLUSIONS: The site of the uterine rupture was random, and was often located at the weakest point of the uterus. There is no effective means for detecting or predicting the weakest point of the uterus. Rapid recognition is key to the treatment of uterine rupture.


Subject(s)
Uterine Rupture , Infant, Newborn , Pregnancy , Female , Humans , Infant , Uterine Rupture/epidemiology , Uterine Rupture/etiology , Uterine Rupture/surgery , Pregnancy Outcome/epidemiology , Cesarean Section/adverse effects , Retrospective Studies , Uterus
5.
BMC Med Imaging ; 24(1): 127, 2024 May 31.
Article in English | MEDLINE | ID: mdl-38822240

ABSTRACT

BACKGROUND: The presence of infarction in patients with unrecognized myocardial infarction (UMI) is a critical feature in predicting adverse cardiac events. This study aimed to compare the detection rate of UMI using conventional and deep learning reconstruction (DLR)-based late gadolinium enhancement (LGEO and LGEDL, respectively) and evaluate optimal quantification parameters to enhance diagnosis and management of suspected patients with UMI. METHODS: This prospective study included 98 patients (68 men; mean age: 55.8 ± 8.1 years) with suspected UMI treated at our hospital from April 2022 to August 2023. LGEO and LGEDL images were obtained using conventional and commercially available inline DLR algorithms. The myocardial signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and percentage of enhanced area (Parea) employing the signal threshold versus reference mean (STRM) approach, which correlates the signal intensity (SI) within areas of interest with the average SI of normal regions, were analyzed. Analysis was performed using the standard deviation (SD) threshold approach (2SD-5SD) and full width at half maximum (FWHM) method. The diagnostic efficacies based on LGEDL and LGEO images were calculated. RESULTS: The SNRDL and CNRDL were two times better than the SNRO and CNRO, respectively (P < 0.05). Parea-DL was elevated compared to Parea-O using the threshold methods (P < 0.05); however, no intergroup difference was found based on the FWHM method (P > 0.05). The Parea-DL and Parea-O also differed except between the 2SD and 3SD and the 4SD/5SD and FWHM methods (P < 0.05). The receiver operating characteristic curve analysis revealed that each SD method exhibited good diagnostic efficacy for detecting UMI, with the Parea-DL having the best diagnostic efficacy based on the 5SD method (P < 0.05). Overall, the LGEDL images had better image quality. Strong diagnostic efficacy for UMI identification was achieved when the STRM was ≥ 4SD and ≥ 3SD for the LGEDL and LGEO, respectively. CONCLUSIONS: STRM selection for LGEDL magnetic resonance images helps improve clinical decision-making in patients with UMI. This study underscored the importance of STRM selection for analyzing LGEDL images to enhance diagnostic accuracy and clinical decision-making for patients with UMI, further providing better cardiovascular care.


Subject(s)
Contrast Media , Deep Learning , Myocardial Infarction , Humans , Middle Aged , Myocardial Infarction/diagnostic imaging , Male , Female , Prospective Studies , Gadolinium , Signal-To-Noise Ratio , Aged , Magnetic Resonance Imaging/methods
6.
BMC Med Imaging ; 23(1): 115, 2023 08 29.
Article in English | MEDLINE | ID: mdl-37644397

ABSTRACT

BACKGROUND: Incidental thymus region masses during thoracic examinations are not uncommon. The clinician's decision-making for treatment largely depends on imaging findings. Due to the lack of specific indicators, it may be of great value to explore the role of radiomics in risk categorization of the thymic epithelial tumors (TETs). METHODS: Four databases (PubMed, Web of Science, EMBASE and the Cochrane Library) were screened to identify eligible articles reporting radiomics models of diagnostic performance for risk categorization in TETs patients. The quality assessment of diagnostic accuracy studies 2 (QUADAS-2) and radiomics quality score (RQS) were used for methodological quality assessment. The pooled area under the receiver operating characteristic curve (AUC), sensitivity and specificity with their 95% confidence intervals were calculated. RESULTS: A total of 2134 patients in 13 studies were included in this meta-analysis. The pooled AUC of 11 studies reporting high/low-risk histologic subtypes was 0.855 (95% CI, 0.817-0.893), while the pooled AUC of 4 studies differentiating stage classification was 0.826 (95% CI, 0.817-0.893). Meta-regression revealed no source of significant heterogeneity. Subgroup analysis demonstrated that the best diagnostic imaging was contrast enhanced computer tomography (CECT) with largest pooled AUC (0.873, 95% CI 0.832-0.914). Publication bias was found to be no significance by Deeks' funnel plot. CONCLUSIONS: This present study shows promise for preoperative selection of high-risk TETs patients based on radiomics signatures with current available evidence. However, methodological quality in further studies still needs to be improved for feasibility confirmation and clinical application of radiomics-based models in predicting risk categorization of the thymic epithelial tumors.


Subject(s)
Neoplasms, Glandular and Epithelial , Thymus Neoplasms , Humans , Thymus Neoplasms/diagnostic imaging , Thymus Neoplasms/surgery , Neoplasms, Glandular and Epithelial/diagnostic imaging , Neoplasms, Glandular and Epithelial/surgery , Databases, Factual , ROC Curve
7.
Int J Mol Sci ; 24(11)2023 May 31.
Article in English | MEDLINE | ID: mdl-37298477

ABSTRACT

Melatonin (MT) and nitric oxide (NO) act as signaling molecules that can enhance cadmium (Cd) stress resistance in plants. However, little information is available about the relationship between MT and NO during seedling growth under Cd stress. We hypothesize that NO may be involved in how MT responds to Cd stress during seedling growth. The aim of this study is to evaluate the relationship and mechanism of response. The results indicate that different concentrations of Cd inhibit the growth of tomato seedlings. Exogenous MT or NO promotes seedling growth under Cd stress, with a maximal biological response at 100 µM MT or NO. The promotive effects of MT-induced seedling growth under Cd stress are suppressed by NO scavenger 2-4-carboxyphenyl-4,4,5,5-tetramethyl-imidazoline-1-oxyl-3-oxide (cPTIO), suggesting that NO may be involved in MT-induced seedling growth under Cd stress. MT or NO decreases the content of hydrogen peroxide (H2O2), malonaldehyde (MDA), dehydroascorbic acid (DHA), and oxidized glutathione (GSSG); improves the content of ascorbic acid (AsA) and glutathione (GSH) and the ratios of AsA/DHA and GSH/GSSG; and enhances the activities of glutathione reductase (GR), monodehydroascorbic acid reductase (MDHAR), dehydroascorbic acid reductase (DHAR), ascorbic acid oxidase (AAO), and ascorbate peroxidase (APX) to alleviate oxidative damage. Moreover, the expression of genes associated with the ascorbate-glutathione (AsA-GSH) cycle and reactive oxygen species (ROS) are up-regulated by MT or NO under Cd conditions, including AAO, AAOH, APX1, APX6, DHAR1, DHAR2, MDHAR, and GR. However, NO scavenger cPTIO reverses the positive effects regulated by MT. The results indicate that MT-mediated NO enhances Cd tolerance by regulating AsA-GSH cycle and ROS metabolism.


Subject(s)
Melatonin , Solanum lycopersicum , Antioxidants/pharmacology , Melatonin/pharmacology , Melatonin/metabolism , Seedlings/metabolism , Cadmium/metabolism , Nitric Oxide/metabolism , Reactive Oxygen Species/metabolism , Glutathione Disulfide/metabolism , Dehydroascorbic Acid/metabolism , Hydrogen Peroxide/metabolism , Ascorbic Acid/pharmacology , Ascorbic Acid/metabolism , Oxidative Stress , Glutathione/metabolism , Oxidoreductases/metabolism
8.
Acta Radiol ; 63(3): 319-327, 2022 Mar.
Article in English | MEDLINE | ID: mdl-33601893

ABSTRACT

BACKGROUND: In December 2019, a rare respiratory disease named coronavirus disease 2019 (COVID-19) broke out, leading to great concern around the world. PURPOSE: To develop and validate a radiomics nomogram for predicting the fatal outcome of COVID-19 pneumonia. MATERIAL AND METHODS: The present study consisted of a training dataset (n = 66) and a validation dataset (n = 30) with COVID-19 from January 2020 to March 2020. A radiomics signature was generated using the least absolute shrinkage and selection operator (LASSO) Cox regression model. A radiomics score (Rad-score) was developed from the training cohort. The radiomics model, clinical model, and integrated model were built to assess the association between radiomics signature/clinical characteristics and the mortality of COVID-19 cases. The radiomics signature combined with the Rad-score and the independent clinical factors and radiomics nomogram were constructed. RESULTS: Seven stable radiomics features associated with the mortality of COVID-19 were finally selected. A radiomics nomogram was based on a combined model consisting of the radiomics signature and the clinical risk factors indicating optimal predictive performance for the fatal outcome of patients with COVID-19 with a C-index of 0.912 (95% confidence interval [CI] 0.867-0.957) in the training dataset and 0.907 (95% CI 0.849-0.966) in the validation dataset. The calibration curves indicated optimal consistency between the prediction and the observation in both training and validation cohorts. CONCLUSION: The CT-based radiomics nomogram indicated favorable predictive efficacy for the overall survival risk of patients with COVID-19, which could help clinicians intensively follow up high-risk patients and make timely diagnoses.


Subject(s)
COVID-19/diagnostic imaging , COVID-19/mortality , Inpatients , Nomograms , Tomography, X-Ray Computed , Confidence Intervals , Datasets as Topic , Humans , Proportional Hazards Models , Retrospective Studies , Risk Factors
9.
Int J Mol Sci ; 23(19)2022 Oct 02.
Article in English | MEDLINE | ID: mdl-36233003

ABSTRACT

Anthocyanins act as polyphenolic pigment that is ubiquitously found in plants. Anthocyanins play a role not only in health-promoting as an antioxidant, but also in protection against all kinds of abiotic and biotic stresses. Most recent studies have found that MYB transcription factors (MYB TFs) could positively or negatively regulate anthocyanin biosynthesis. Understanding the roles of MYB TFs is essential in elucidating how MYB TFs regulate the accumulation of anthocyanin. In the review, we summarized the signaling pathways medicated by MYB TFs during anthocyanin biosynthesis including jasmonic acid (JA) signaling pathway, cytokinins (CKs) signaling pathway, temperature-induced, light signal, 26S proteasome pathway, NAC TFs, and bHLH TFs. Moreover, structural and regulator genes induced by MYB TFs, target genes bound and activated or suppressed by MYB TFs, and crosstalk between MYB TFs and other proteins, were found to be vitally important in the regulation of anthocyanin biosynthesis. In this study, we focus on the recent knowledge concerning the regulator signaling and mechanism of MYB TFs on anthocyanin biosynthesis, covering the signaling pathway, genes expression, and target genes and protein expression.


Subject(s)
Anthocyanins , Transcription Factors , Antioxidants , Basic Helix-Loop-Helix Transcription Factors/genetics , Basic Helix-Loop-Helix Transcription Factors/metabolism , Cytokinins , Gene Expression Regulation, Plant , Plant Proteins/metabolism , Plants/genetics , Plants/metabolism , Plants, Genetically Modified/metabolism , Transcription Factors/metabolism
10.
Opt Lett ; 46(19): 4844-4847, 2021 Oct 01.
Article in English | MEDLINE | ID: mdl-34598214

ABSTRACT

The infrared reflectance spectrum of cubic boron phosphide (BP) single crystals shows a very narrow Reststrahlen band, indicating a small TO-LO (transverse optical-longitudinal optical) splitting. To study the phonon thermal behavior of the TO(Γ) and the LO(Γ) of 10BP, natBP, and 11BP bulk single crystals, temperature-dependent infrared reflectance spectroscopy in 85-500 K is applied here. As the temperature increases, the Reststrahlen band broadens. The frequencies of the TO(Γ) and the LO(Γ) exhibit nonlinear red shifts, and the TO-LO splitting gradually increases. Our research found that thermal expansion plays a leading role at low temperatures while phonon anharmonicity gradually takes place at high temperatures.

11.
Epidemiol Infect ; 148: e94, 2020 05 06.
Article in English | MEDLINE | ID: mdl-32374248

ABSTRACT

Coronavirus disease 2019 (COVID-19) patients were classified into four clinical stages (uncomplicated illness, mild, severe and critical pneumonia) depending on disease severity. We aim to investigate the corresponding clinical, radiological and laboratory characteristics between different clinical stages. A retrospective, single-centre study of 101 confirmed patients with COVID-19 at Renmin Hospital of Wuhan University from 2 January to 28 January 2020 was enrolled; follow-up endpoint was on 8 February 2020. Clinical data were collected and compared during the course of illness. The median age of the 101 patients was 51.0 years and 33.6% were medical staff. Fever (68%), cough (50%) and fatigue (23%) are the most common symptoms. About 26% patients underwent the mechanical ventilation and 98% patients were treated with antibiotics. Thirty-seven per cent patients were cured and 11 died. On admission, the number of patients with uncomplicated illness, mild, severe and critical pneumonia were 2 [2%], 86 [85%], 11 [11%] and 2 [2%]. Forty-four of the 86 mild pneumonia progressed to severe illness within 4 days, with nine patients worsened due to critical pneumonia within 4 days. Two of the 11 severe patients improved to mild condition while three others deteriorated. Significant differences were observed among groups of different clinical stages in numbers of influenced pulmonary segments (6 vs. 12 vs. 17, P < 0.001). A significantly upward trend was witnessed in ground-glass opacities overlapped with striped shadows (33% vs. 42% vs. 55% vs. 80%, P < 0.001), while pure ground-glass opacities gradually decreased as disease progressed (45% vs. 35% vs. 24% vs. 13%, P < 0.001) within 12 days. Lymphocytes, prealbumin and albumin showed a downtrend as disease progressed from mild to severe or critical condition, an uptrend was found in white blood cells, C-reactive protein, neutrophils and lactate dehydrogenase. The proportions of serum amyloid A > 300 mg/l in mild, severe and critical conditions were 18%, 46% and 71%, respectively.


Subject(s)
Coronavirus Infections/physiopathology , Coronavirus Infections/therapy , Pneumonia, Viral/physiopathology , Pneumonia, Viral/therapy , Adult , COVID-19 , China/epidemiology , Coronavirus Infections/epidemiology , Female , Health Status Indicators , Humans , Male , Middle Aged , Pandemics , Pneumonia, Viral/epidemiology , Prognosis , Severity of Illness Index
12.
Angew Chem Int Ed Engl ; 59(40): 17648-17656, 2020 Sep 28.
Article in English | MEDLINE | ID: mdl-32558985

ABSTRACT

Two new pyrophosphates nonlinear optical (NLO) materials, Rb3 PbBi(P2 O7 )2 (I) and Cs3 PbBi(P2 O7 )2 (II), were successfully designed and synthesized. Both compounds exhibit large NLO effects and birefringences. Material I presents the scarce case of possessing the coexistence of large birefringence (0.031 at 1064 nm and 0.037 at 532 nm) and second harmonic generation (SHG) response (2.8× potassium dihydrogen phosphate (KDP)) in ultraviolet NLO phosphates and its SHG is the largest in the phase-matching (PM) pyrophosphates. Both I and II have three-dimensional (3D) crystal structures composed of corner-shared RbO12 (CsO11 ), RbO10 (CsO10 ), BiO6 , PbO7 (PbO6 ) and P2 O7 groups, in which P2 O7 and PbO7 (PbO6 ) units form an alveolate [PbPO]∞ skeleton frame. Theoretical calculations reveal that the P-O, Bi-O and Pb-O units are mainly responsible for the moderate birefringence and large SHG efficiency of I.

14.
Inorg Chem ; 57(17): 10568-10575, 2018 Sep 04.
Article in English | MEDLINE | ID: mdl-30124046

ABSTRACT

Two new isotypic diphosphates, RbLiZnP2O7 (RLZP) and CsLiZnP2O7 (CLZP), have been synthesized by a high-temperature solid-phase method. They both crystallize in the Pnma space group (No. 62) and have similar crystal configurations. ALiZnP2O7 (A = Rb, Cs) consists of a [Li2Zn2P4O20]14- anionic skeleton, which is composed of Li/ZnO4 tetrahedral and diphosphate groups, and the Rb or Cs atoms are located in the large hole. In this paper, we discuss the structures of the title compounds and isonomic AA'ZnP2O7 (A = alkali metal); it is found that the ionic radii of the cations and bond angles have an effect on the symmetry of the compounds. By analysis, we found that the M/P values have some effect on the dimensionality of the anionic groups in phosphates containing P2O7 groups. Thermal and spectral analyses are carried out on the title compounds. Besides that mentioned above, we also studied the relationship between the electronic structures and optical properties by theoretical calculations.

16.
J Am Chem Soc ; 136(6): 2302-12, 2014 Feb 12.
Article in English | MEDLINE | ID: mdl-24484302

ABSTRACT

The unique enhanced sensitivity of vibrational circular dichroism (VCD) to the formation and development of amyloid fibrils in solution is extended to four additional fibril-forming proteins or peptides where it is shown that the sign of the fibril VCD pattern correlates with the sense of supramolecular filament chirality and, without exception, to the dominant fibril morphology as observed in AFM or SEM images. Previously for insulin, it has been demonstrated that the sign of the VCD band pattern from filament chirality can be controlled by adjusting the pH of the incubating solution, above pH 2 for "normal" left-hand-helical filaments and below pH 2 for "reversed" right-hand-helical filaments. From AFM or SEM images, left-helical filaments form multifilament braids of left-twisted fibrils while the right-helical filaments form parallel filament rows of fibrils with a flat tape-like morphology, the two major classes of fibril morphology that from deep UV resonance Raman scattering exhibit the same cross-ß-core secondary structure. Here we investigate whether fibril supramolecular chirality is the underlying cause of the major morphology differences in all amyloid fibrils by showing that the morphology (twisted versus flat) of fibrils of lysozyme, apo-α-lactalbumin, HET-s (218-289) prion, and a short polypeptide fragment of transthyretin, TTR (105-115), directly correlates to their supramolecular chirality as revealed by VCD. The result is strong evidence that the chiral supramolecular organization of filaments is the principal underlying cause of the morphological heterogeneity of amyloid fibrils. Because fibril morphology is linked to cell toxicity, the chirality of amyloid aggregates should be explored in the widely used in vitro models of amyloid-associated diseases.


Subject(s)
Amyloid/chemistry , Circular Dichroism , Hydrogen-Ion Concentration , Microscopy, Electron, Scanning , Muramidase/chemistry , Protein Structure, Secondary , Stereoisomerism , Vibration
17.
Eur J Radiol ; 175: 111468, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38648727

ABSTRACT

PURPOSE: This study aimed to construct a predictive model integrating deep learning-derived radiomic features from computed tomography angiography (CTA) and clinical biomarkers to forecast postoperative adverse events (AEs) in patients with acute uncomplicated Stanford type B aortic dissection (uTBAD) undergoing initial thoracic endovascular aortic repair (TEVAR). METHODS: We retrospectively evaluated 369 patients treated with TEVAR for acute uTBAD from January 2015 to December 2022. A three-dimensional (3D) deep convolutional neural network (CNN) automated radiomic feature extraction from CTA images. Feature selection, using Analysis of Variance (ANOVA) and the Least Absolute Shrinkage and Selection Operator (LASSO) algorithms, refined a radiomic score (Rad-Score). This score, alongside clinical parameters, was modelled via Extreme Gradient Boosting (XGBoost) analysis. Model calibration was assessed by calibration curves. RESULTS: The integration of the Rad-Score with clinical factors including albumin and C-reactive protein levels moderately enhanced predictive efficiency, exhibiting an area under the curve (AUC) of 1.000 (95%CI, 1.000-1.000) in the training cohort and 0.990 (95%CI, 0.966-1.000) in the internal validation cohort. In an independent validation cohort from another hospital, the combined model yielded an AUC of 0.985 (95%CI, 0.965-1.000), with an accuracy, precision, sensitivity, and specificity of 0.92, 0.92, 0.94, and 0.91, respectively. CONCLUSIONS: The synergistic application of deep learning-based radiomics from CTA and clinical indicators holds promise for anticipating AEs post-initial thoracic endovascular aortic repair in patients with acute uTBAD. The clinical utility of the constructed combined model, offering prognostic foresight during follow-up, has been substantiated.


Subject(s)
Aortic Aneurysm, Thoracic , Aortic Dissection , Computed Tomography Angiography , Deep Learning , Endovascular Procedures , Postoperative Complications , Humans , Aortic Dissection/diagnostic imaging , Aortic Dissection/surgery , Male , Female , Endovascular Procedures/methods , Retrospective Studies , Middle Aged , Computed Tomography Angiography/methods , Aortic Aneurysm, Thoracic/surgery , Aortic Aneurysm, Thoracic/diagnostic imaging , Postoperative Complications/diagnostic imaging , Aged , Predictive Value of Tests , Acute Disease , Radiomics
18.
Front Plant Sci ; 15: 1330948, 2024.
Article in English | MEDLINE | ID: mdl-38828220

ABSTRACT

Abscisic acid (ABA) and nitric oxide (NO), as unique signaling molecules, are involved in plant growth, developmental processes, and abiotic stresses. However, the interaction between ABA and NO under abiotic stresses has little been worked out at present. Therefore, this paper reviews the mechanisms of crosstalk between ABA and NO in the regulation of plants in response to environmental stresses. Firstly, ABA-NO interaction can alleviate the changes of plant morphological indexes damaged by abiotic stresses, for instance, root length, leaf area, and fresh weight. Secondly, regulatory mechanisms of interaction between ABA and NO are also summarized, such as reactive oxygen species (ROS), antioxidant enzymes, proline, flavonoids, polyamines (PAs), ascorbate-glutathione cycle, water balance, photosynthetic, stomatal movement, and post-translational modifications. Meanwhile, the relationships between ABA and NO are established. ABA regulates NO through ROS at the physiological level during the regulatory processes. At the molecular level, NO counteracts ABA through mediating post-translational modifications. Moreover, we also discuss key genes related to the antioxidant enzymes, PAs biosynthesis, ABA receptor, NO biosynthesis, and flavonoid biosynthesis that are regulated by the interaction between ABA and NO under environmental stresses. This review will provide new guiding directions for the mechanism of the crosstalk between ABA and NO to alleviate abiotic stresses.

19.
Article in English | MEDLINE | ID: mdl-39207633

ABSTRACT

In this study, we developed a novel co-administration of curcumin and sorafenib using a Self micro-emulsifying Drug Delivery System (SMEDDS) called Sorafenib-Curcumin Self micro-emulsifying Drug Delivery System (SOR-CUR-SMEDDS). The formulation was optimized using star point design-response surface methodology, and in vitro cellular experiments were conducted to evaluate the delivery ratio and anti-tumor efficacy of the curcumin and sorafenib combination. The SOR-CUR-SMEDDS exhibited a small size distribution of 13.48 ± 0.61 nm, low polydispersity index (PDI) of 0.228 ± 0.05, and negative zeta potential (ZP) of - 12.4 mV. The half maximal inhibitory concentration (IC50) of the SOR-CUR-SMEDDS was 3-fold lower for curcumin and 5-fold lower for sorafenib against HepG2 cells (human hepatocellular carcinoma cells). Transmission electron microscopy (TEM) and particle size detection confirmed that the SOR-CUR-SMEDDS droplets were uniformly round and within the nano-emulsion particle size range of 10-20 nm. The SMEDDS were characterized then studied for drug release in vitro via dialysis membranes. Curcumin was released more completely in the combined delivery system, showing the largest in vitro drug release (79.20%) within 7 days in the medium, while the cumulative release rate of sorafenib in the release medium was low, reaching 58.96% on the 7 day. In vitro pharmacokinetic study, it demonstrated a significant increase in oral bioavailability of sorafenib (1239.88-fold) and curcumin (3.64-fold) when administered in the SMEDDS. These findings suggest that the SMEDDS formulation can greatly enhance drug solubility, improve drug absorption and prolong circulation in vivo, leading to increased oral bioavailability of sorafenib and curcumin.

20.
Front Psychiatry ; 15: 1449202, 2024.
Article in English | MEDLINE | ID: mdl-39323962

ABSTRACT

Background: The diagnosis of major depressive disorder (MDD) mainly depends on subjective clinical symptoms, without an acceptable objective biomarker for the clinical application of MDD. Inter-alpha-trypsin inhibitor heavy chain 4 (ITIH4) showed a high specificity as biomarker for the diagnosis and treatment of MDD. The present study aimed to investigate differences in plasma ITIH4 in two different aged MDD patients and underlying pathological mechanisms of plasma ITIH4 in the occurrence and development of MDD. Methods: Sixty-five adult MDD patients, 51 adolescent MDD patients, and 64 healthy controls (HCs) were included in the present study. A 14-days' antidepressive treatment was conducted in all MDD patients. Psychological assessments were performed and plasma ITIH4 and astrocyte-related markers were detected for all participants. Results: (1) Plasma levels of ITIH4 in adult MDD patients were significantly higher than adolescent MDD patients and HCs, and significantly increased plasma ITIH4 levels was observed in adolescent MDD patients compared with HCs (2). There were positive correlations between plasma ITIH4 levels and 24-item Hamilton Depression Scale (HAMD-24) scores and plasma glial fibrillary acidic protein (GFAP) levels in MDD patients, however, plasma ITIH4 levels were significantly correlated with age just in adult MDD patients (3). Plasma ITIH4 showed area under the curve values of 0.824 and 0.729 to differentiate adult MDD patients and adolescent MDD patients from HCs, respectively (4). There was significant decrease in plasma levels of ITIH4 between before and after antidepressive treatment in adult MDD patients, but not in adolescent MDD patients (5). Changed value of ITIH4 levels were correlated with the changed value of GFAP levels and changed rate of HAMD-24 scores in adult MDD patients following antidepressive treatment. Conclusion: Plasma ITIH4 may be potential plasma biomarkers of MDD with age-related specificity, which was associated with depressive symptoms astrocyte-related pathologic changes, and antidepressive treatment efficacy.

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