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1.
J Agric Food Chem ; 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38602386

RESUMO

The genus Salix L. is traditionally used in folk medicine to alleviate pain caused by various kinds of inflammation. In the present study, 10 undescribed salicin derivatives along with 5 known congeners were isolated from the barks of Salix tetrasperma, and their structures were elucidated by spectroscopic analyses, single-crystal X-ray diffraction, electronic circular dichroism (ECD) calculations, and chemical conversions. Compounds 4-6 significantly inhibited NO production in lipopolysaccharide (LPS)-induced RAW 264.7 macrophages, and the most active 4 obviously suppressed the production of IL-1ß and IL-6 and decreased iNOS and COX-2 expression in a dose-dependent manner. Further Western blotting analysis revealed that the anti-inflammatory mechanism of 4 is possibly mediated through the MAPK and NF-κB signaling pathways.

2.
Ecol Evol ; 14(4): e11225, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38584774

RESUMO

A new species of Papaveraceae, Corydalis sunhangii, in the section Trachycarpae, is described and illustrated from Nyingchi City, Xizang, China. The new species has some resemblance to Corydalis kingdonis, but differs by radical leaves prominent, usually several, blade tripinnate (vs. insignificant, few, blade bi- to triternate); cauline leaf usually one, much smaller than radical leaves, usually situated in lower half of stem (vs. usually two, larger than radical leaves, concentrated in upper third of stem); racemes densely 13-35-flowered (vs. rather lax, 4-11-flowered); claw of lower petal shallowly saccate (vs. very prominently and deeply saccate); capsule oblong, with raised lines of dense papillae (vs. broadly obovoid, smooth). Phylogenetic analysis, based on 68 protein-coding plastid genes of 49 samples, shows that C. sunhangii is not closely related to any hitherto described species, which is consistent with our morphological analysis.

3.
Food Chem ; 448: 139141, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38574716

RESUMO

Hydrothermal carbonization (HTC) is an effective strategy for high-value utilization of tea residue (TR), and it was noticed the aqueous phase (AP) has not been extensively studied. This study aimed to investigate the chemical components and characteristics of the AP, and applied it in active food packaging films. The results showed that the total phenolic content of AP was 1.86 mg GAE/mL, and the main compounds in AP were organic acids, alcohols, and amino acids. The AP showed excellent antibacterial activity and antioxidant capacity. The active films were prepared using the casting method. The 4:7-AP/PVA film showed outstanding mechanical properties (tensile strength = 34.18 MPa, elongation at break = 458.67%), antioxidant ability (DPPH scavenging capacity 92.01%), antibacterial activity, water resistance and biocompatibility. The banana preservation test showed the AP/PVA films could successfully prolong the shelf-life of bananas and have the potential to be food packaging films.

4.
Dalton Trans ; 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38587258

RESUMO

The synthesis of nanosized ZSM-5 zeolites with high crystallinity and suitable acidity is very significant for their great potential in various catalytic applications. Herein, a series of zeolite ZSM-5 crystals with different particle sizes and SiO2/Al2O3 ratios (10-30) were synthesized by a temperature-varying two-step crystallization method in a concentrated gel system containing L-lysine and/or polyvinylpyrrolidone (PVP) additives. By optimizing the addition amounts of the two additives, the crystal size of the ZSM-5 zeolite could be reduced to less than 100 nm. Meanwhile, relatively high crystallinity and framework Al incorporation rates could be achieved, resulting in the generation of high-quality ZSM-5 nanocrystals. The nanosized H-form ZSM-5 zeolite with a SiO2/Al2O3 ratio of 20 showed enhanced catalytic efficiency and stability for the alkylation of 2-methylnaphthalene (2-MN) with methanol to produce an important intermediate, 2,6-dimethylnaphthalene (2,6-DMN). A relatively high and steady yield of 2,6-DMN (above 7.2%) could be achieved during 20 h time-on-stream at 400 °C. The smaller crystal size, higher crystallinity and framework Al content could provide more accessible Brønsted acid sites in the 10-membered ring channel of the ZSM-5 nanocrystals, which are the main active sites responsible for the shape-selectivity of the targeted product of 2,6-DMN. As a result, the formation of other side products like 1-MN and poly-MN could be effectively inhibited, thus leading to an improved 2,6-DMN yield and coke resistance over the nanosized ZSM-5 catalyst.

5.
Insects ; 15(3)2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38535372

RESUMO

X-ray irradiation and modified atmospheres (MAs) provide eco-friendly, chemical-free methods for pest management. Although a low-oxygen atmospheric treatment improves the performance of some irradiated insects, its influence on the irradiation of quarantine insects and its impacts on pest control efficacy have yet to be investigated. Based on bioassay results, this study employed direct immersion solid-phase microextraction (DI-SPME) combined with gas chromatography-mass spectrometry (GC-MS) to determine metabolic profiles of late third-instar B. dorsalis larvae under normoxia (CON, Air), hypoxia (95% N2 + 5% O2, HY), super-hypoxia (99.5% N2 + 0.5% O2, Sup-HY), irradiation-alone (116 Gy, IR-alone), hypoxia + irradiation (HY + IR) and super-hypoxia + irradiation (Sup-HY + IR). Our findings reveal that, compared to the IR-alone group, the IR treatment under HY and Sup-HY (HY + IR and Sup-HY + IR) increases the larval pupation of B. dorsalis, and weakens the delaying effect of IR on the larval developmental stage. However, these 3 groups further hinder adult emergence under the phytosanitary IR dose of 116 Gy. Moreover, all IR-treated groups, including IR-alone, HY + IR, and Sup-HY + IR, lead to insect death as a coarctate larvae or pupae. Pathway analysis identified changed metabolic pathways across treatment groups. Specifically, changes in lipid metabolism-related pathways were observed: 3 in HY vs. CON, 2 in Sup-HY vs. CON, and 5 each in IR-alone vs. CON, HY + IR vs. CON, and Sup-HY + IR vs. CON. The treatments of IR-alone, HY + IR, and Sup-HY + IR induce comparable modifications in metabolic pathways. However, in the HY + IR, and Sup-HY + IR groups, the third-instar larvae of B. dorsalis demonstrate significantly fewer changes. Our research suggests that a low-oxygen environment (HY and Sup-HY) might enhance the radiation tolerance in B. dorsalis larvae by stabilizing lipid metabolism pathways at biologically feasible levels. Additionally, our findings indicate that the current phytosanitary IR dose contributes to the effective management of B. dorsalis, without being influenced by radioprotective effects. These results hold significant importance for understanding the biological effects of radiation on B. dorsalis and for developing IR-specific regulatory guidelines under MA environments.

6.
Commun Biol ; 7(1): 280, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38448784

RESUMO

X-ray computed tomography (XCT) and X-ray fluorescence (XRF) imaging are two non-invasive imaging techniques to study cellular structures and chemical element distributions, respectively. However, correlative X-ray computed tomography and fluorescence imaging for the same cell have yet to be routinely realized due to challenges in sample preparation and X-ray radiation damage. Here we report an integrated experimental and computational workflow for achieving correlative multi-modality X-ray imaging of a single cell. The method consists of the preparation of radiation-resistant single-cell samples using live-cell imaging-assisted chemical fixation and freeze-drying procedures, targeting and labeling cells for correlative XCT and XRF measurement, and computational reconstruction of the correlative and multi-modality images. With XCT, cellular structures including the overall structure and intracellular organelles are visualized, while XRF imaging reveals the distribution of multiple chemical elements within the same cell. Our correlative method demonstrates the feasibility and broad applicability of using X-rays to understand cellular structures and the roles of chemical elements and related proteins in signaling and other biological processes.


Assuntos
Pesquisa , Tomografia Computadorizada por Raios X , Raios X , Radiografia , Imagem Óptica
7.
Sci Adv ; 10(13): eadi9035, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38552007

RESUMO

The pharyngeal endoderm, an innovation of deuterostome ancestors, contributes to pharyngeal development by influencing the patterning and differentiation of pharyngeal structures in vertebrates; however, the evolutionary origin of the pharyngeal organs in vertebrates is largely unknown. The endostyle, a distinct pharyngeal organ exclusively present in basal chordates, represents a good model for understanding pharyngeal organ origins. Using Stereo-seq and single-cell RNA sequencing, we constructed aspatially resolved single-cell atlas for the endostyle of the ascidian Styela clava. We determined the cell composition of the hemolymphoid region, which illuminates a mixed ancestral structure for the blood and lymphoid system. In addition, we discovered a cluster of hair cell-like cells in zone 3, which has transcriptomic similarity with the hair cells of the vertebrate acoustico-lateralis system. These findings reshape our understanding of the pharynx of the basal chordate and provide insights into the evolutionary origin of multiplexed pharyngeal organs.


Assuntos
Urocordados , Animais , Urocordados/genética , Faringe , Vertebrados , Evolução Biológica , Diferenciação Celular
8.
Org Lett ; 26(11): 2326-2331, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38451219

RESUMO

Direct alkene C-H/N-H cross dehydrogenative coupling is an infrequent, highly challenging transformation. Herein, a photoredox radical-radical cross-coupling reaction between ketene dithioacetal as a persistent alkene radical cation and azole nitrogen center radical (NCR) was developed. This direct alkene amination proceeded through a synergistic photoredox and cobalt catalysis, with only H2 evolution. The reaction showed excellent tolerance and highly regio- and stereospecific manner, expanding the scope of C(sp2)-N construction methods and radical cross-coupling modes.

9.
BMC Public Health ; 24(1): 836, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38500120

RESUMO

BACKGROUND: Hemodialysis patients require a reasonable dietary intake to manage their disease progression effectively. However, there is limited research on these patients' overall dietary knowledge, attitude, and practice (KAP) status. This study aimed to investigate the dietary KAP status and latent profiles in hemodialysis patients and identify sociodemographic and disease-related factors associated with these profiles and dietary practice. METHODS: A multicenter cross-sectional study involving 425 hemodialysis patients was conducted. A dietary KAP questionnaire in hemodialysis patients was used to evaluate the dietary KAP of the patients. A structural equation model was employed to analyze the correlations between dietary knowledge, attitude, and practice. Multiple linear regression analysis was used to identify factors associated with dietary practice scores. Latent profile analysis was conducted to determine the latent profiles of dietary KAP, and binary logistic regression was used to explore the sociodemographic and disease-related characteristics associated with each KAP profile in hemodialysis patients. RESULTS: The normalized average scores for dietary knowledge, attitude, and practice in hemodialysis patients were 0.58, 0.82, and 0.58, respectively. The structural equation model revealed significant positive correlations between dietary knowledge and attitude, and attitude and practice. Attitude played an indirect effect between knowledge and practice. Gender, cerebrovascular disease, and dietary attitude scores were identified as independent influencing factors for dietary practice scores. Two dietary KAP profiles were developed: a profile with general knowledge and attitude but low practice (40.2%) and a profile with general knowledge and attitude and high practice (59.8%). Binary logistic regression analysis indicated gender and monthly income per household significantly predicted membership in each KAP profile. CONCLUSIONS: The dietary practice of hemodialysis patients requires improvement. It is necessary to develop more individualized dietary interventions for these patients. Further exploration is needed to understand the motivation of patients to change their dietary behavior.


Assuntos
Dieta , Estado Nutricional , Humanos , Estudos Transversais , Renda , Características da Família , Conhecimentos, Atitudes e Prática em Saúde
10.
Int Immunopharmacol ; 130: 111747, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38442576

RESUMO

Phosphatidylinositol 3-kinase (PI3K) is frequently hyperactivated in cancer, playing pivotal roles in the pathophysiology of both malignant and immune cells. The impact of PI3K inhibitors on the tumor microenvironment (TME) within lung cancer remains largely unknown. In this study, we explored the regulatory effects of GNE-493, an innovative dual inhibitor of PI3K and mammalian target of rapamycin (mTOR), on the TME of lung cancer. First, through the analysis of The Cancer Genome Atlas-lung squamous cell carcinoma (LUSC) cohort, we found PIK3CA to be related to CD8 T cells, which may affect the overall survival rate of patients by affecting CD8 function. We herein demonstrated that GNE-493 can significantly inhibit tumor cell proliferation and promote cell apoptosis while increasing the expression of the immunogenic death-related molecules CRT and HSP70 using in vitro cell proliferation and apoptosis experiments on the murine KP lung cancer cell line and human A549 lung cancer cell line. Next, through the establishment of an orthotopic tumor model in vivo, it was found that after GNE-493 intervention, the infiltration of CD4+ and CD8+ T cells in mouse lung tumor was significantly increased, and the expression of CRT in tumors could be induced to increase. To explore the mechanisms underlying PI3K inhibition-induced changes in the TME, the gene expression differences of T cells in the control group versus GNE-493-treated KP tumors were analyzed by RNA-seq, and the main effector pathway of anti-tumor immunity was identified. The IFN/TNF family molecules were significantly upregulated after GNE-493 treatment. In summary, our findings indicate that GNE-493 promotes immunogenic cell death in lung cancer cells, and elucidates its regulatory impact on molecules associated with the adaptive immune response. Our study provides novel insights into how PI3K/mTOR inhibitors exert their activity by modulating the tumor-immune interaction.


Assuntos
Morte Celular Imunogênica , Neoplasias Pulmonares , Fosfatidilinositol 3-Quinase , Inibidores de Fosfoinositídeo-3 Quinase , Animais , Humanos , Camundongos , Linfócitos T CD8-Positivos/metabolismo , Linhagem Celular Tumoral , Classe I de Fosfatidilinositol 3-Quinases , Morte Celular Imunogênica/efeitos dos fármacos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/imunologia , Fosfatidilinositol 3-Quinase/metabolismo , Transdução de Sinais , Microambiente Tumoral , Inibidores de Fosfoinositídeo-3 Quinase/farmacologia , Células A549 , Feminino , Camundongos Endogâmicos C57BL
11.
Animals (Basel) ; 14(6)2024 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-38539951

RESUMO

Zoo animals, harboring zoonotic gastrointestinal protozoal diseases, pose potential hazards to the safety of visitors and animal keepers. This study involved the collection and examination of 400 fresh fecal samples from 68 animal species, obtained from five zoos. The aim of this study was to determine the occurrence, genetic characteristics, and zoonotic potential of common gastrointestinal protists. PCR or nested PCR analysis was conducted on these samples to detect four specific parasites: Cryptosporidium spp., Giardia duodenalis, Enterocytozoon bieneusi, and Blastocystis spp. The overall prevalence of Cryptosporidium spp was 0.5% (2/400), G. duodenalis was 6.0% (24/400), Blastocystis spp. was 24.5% (98/400), and E. bieneusi was 13.5% (54/400). G. duodenalis, Blastocystis spp., and E. bieneusi were detected in all of the zoos, exhibiting various zoonotic genotypes or subtypes. G. duodenalis-positive samples exhibited three assemblages (D, E, and B). Blastocystis spp. subtypes (ST1, ST2, ST3, ST4, ST5, ST8, ST10, ST13, and ST14) and one unknown subtype (ST) were identified. A total of 12 genotypes of E. bieneusi were identified, including SC02, BEB6, Type IV, pigEBITS 7, Peru8, PtEb IX, D, CD9, EbpC, SCBB1, CM4, and CM7. Moreover, significant differences in the positive rates among different zoos were observed (p < 0.01). The findings indicate that zoo animals in China are affected by a range of intestinal protozoa infections. Emphasizing molecular identification for specific parasite species or genotypes is crucial for a better understanding of the zoonotic risk. Preventing and controlling parasitic diseases in zoos is not only vital for zoo protection and management but also holds significant public health implications.

12.
Food Chem X ; 22: 101251, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38440059

RESUMO

Oil-in-water (O/W) high internal phase (HIP) emulsion was prepared to investigate its effects on the physicochemical properties and antimicrobial properties of soy protein isolate (SPI)-based films. The particle size and migration degree of oil droplets in the SPI film-forming solution with HIP emulsion and the films were lower than those with conventional O/W emulsion or oil. The SPI-based emulsion films with HIP emulsion containing 30 % oil had the lowest water vapor permeability (1.15 × 10-10 g·m-1·s-1·Pa-1), glass transition temperature (40.93 °C) and tensile strength (4.47 MPa), and the highest transparency value (12.87) and elongation at break (160.83 %). The antimicrobial test of the SPI-based emulsion films loaded with thymol showed that the thymol encapsulation efficiency, sustained release effect, and growth inhibition effect on microbes were higher for the films with HIP emulsion than those for the films with O/W emulsion or oil.

13.
Int J Mol Sci ; 25(5)2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38473741

RESUMO

Iron is an indispensable nutrient for the survival of Toxoplasma gondii; however, excessive amounts can lead to toxicity. The parasite must overcome the host's "nutritional immunity" barrier and compete with the host for iron. Since T. gondii can infect most nucleated cells, it encounters increased iron stress during parasitism. This study assessed the impact of iron stress, encompassing both iron depletion and iron accumulation, on the growth of T. gondii. Iron accumulation disrupted the redox balance of T. gondii while enhancing the parasite's ability to adhere in high-iron environments. Conversely, iron depletion promoted the differentiation of tachyzoites into bradyzoites. Proteomic analysis further revealed proteins affected by iron depletion and identified the involvement of phosphotyrosyl phosphatase activator proteins in bradyzoite formation.


Assuntos
Parasitos , Toxoplasma , Animais , Toxoplasma/metabolismo , Proteômica , Diferenciação Celular
14.
Parasit Vectors ; 17(1): 118, 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38459572

RESUMO

BACKGROUND: Neospora caninum is an apicomplexan parasite that is particularly responsible for abortions in cattle and neuromuscular disease in dogs. Due to the limited effectiveness of currently available drugs, there is an urgent need for new therapeutic approaches to control neosporosis. Luciferase-based assays are potentially powerful tools in the search for antiprotozoal compounds, permitting the development of faster and more automated assays. The aim of this study was to construct a luciferase-expressing N. caninum and evaluate anti-N. caninum drugs. METHODS: Luciferase-expressing N. caninum (Nc1-Luc) was constructed using clustered regularly interspaced short palindromic repeats (CRISPR)-associated protein 9 (CRISPR/Cas9). After testing the luciferase expression and phenotype of the Nc1-Luc strains, the drug sensitivity of Nc1-Luc strains was determined by treating them with known positive or negative drugs and calculating the half-maximal inhibitory concentration (IC50). The selective pan-rapidly accelerated fibrosarcoma (pan-RAF) inhibitor TAK-632 was then evaluated for anti-N. caninum effects using Nc1-Luc by luciferase activity reduction assay and other in vitro and in vivo studies. RESULTS: The phenotypes and drug sensitivity of Nc1-Luc strains were consistent with those of the parental strains Nc1, and Nc1-Luc strains can be used to determine the IC50 for anti-N. caninum drugs. Using the Nc1-Luc strains, TAK-632 showed promising activity against N. caninum, with an IC50 of 0.6131 µM and a selectivity index (SI) of 62.53. In vitro studies demonstrated that TAK-632 inhibited the invasion, proliferation, and division of N. caninum tachyzoites. In vivo studies showed that TAK-632 attenuated the virulence of N. caninum in mice and significantly reduced the parasite burden in the brain. CONCLUSIONS: In conclusion, a luciferase-expressing N. caninum strain was successfully constructed, which provides an effective tool for drug screening and related research on N. caninum. In addition, TAK-632 was found to inhibit the growth of N. caninum, which could be considered as a candidate lead compound for new therapeutics for neosporosis.


Assuntos
Doenças dos Bovinos , Coccidiose , Doenças do Cão , Neospora , Nitrilas , Doenças dos Roedores , Gravidez , Feminino , Animais , Camundongos , Bovinos , Cães , Coccidiose/tratamento farmacológico , Coccidiose/veterinária , Coccidiose/parasitologia , Neospora/genética , Avaliação Pré-Clínica de Medicamentos , Benzotiazóis/metabolismo , Benzotiazóis/farmacologia , Benzotiazóis/uso terapêutico
15.
Int J Biol Macromol ; 262(Pt 2): 130084, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38350584

RESUMO

Accidental bleeding is an unavoidable problem in daily life. To avoid the risk of excessive blood loss, it is urgent to design a functional material that can quickly stop bleeding. In this study, an efficient wound dressing for hemostasis was investigated. Based on the characteristics that Ca2+ and fish skin collagen (FSC) could activate the coagulation mechanism, hemostatic cotton was prepared by solvent replacement method using CaCl2, FSC, soluble starch (SS), and polyvinyl alcohol (PVA) as raw materials. The cytotoxicity test showed the Ca2+PVA/FSC-SS hemostatic cottons had good biocompatibility. The activated partial thromboplastin time (APTT) of Ca2+PVA/FSC-SS(4) was 35.34 s, which was 22.07 s faster than that of PVA/FSC-SS, indicating Ca2+PVA/FSC-SS mediated the endogenous coagulation system. In vitro coagulation test, Ca2+PVA/FSC-SS(4) could stop bleeding rapidly within 39.60 ± 5.16 s, and the ability of wound healing was higher than commercial product (Celox). This study developed a rapid procoagulant and hemostatic material, which had a promising application in a variety of environments.


Assuntos
Hemostáticos , Animais , Hemostáticos/farmacologia , Amido/farmacologia , Hemostasia , Coagulação Sanguínea , Colágeno , Álcool de Polivinil , Hemorragia , Etanol , Antibacterianos
16.
Front Plant Sci ; 15: 1334958, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38379940

RESUMO

Introduction: Asexual reproduction of Gastrodia elata Bl. f. glauca S. chow (GeB) produces degeneration with increasing number of GeB. Therefore, we analyzed the microorganisms of GeB seedlings and surrounding soil by Illumina Miseq high-throughput sequencing technology. Methods: In this study, Illumina Miseq high-throughput sequencing technology was applied to analyze the types and quantities of GeB seedlings and surrounding soil microorganisms in the first to third generations of asexual reproduction, isolated and identified the dominant strains of GeB in the first to third generations and screened the antagonistic bacteria of its pathogenic fungi, and evaluated the effects of beneficial bacteria on the production performance of seedlings planted with GeB. Results: With an increase in the number of asexual reproductive generations, the number of pathogenic fungi and bacteria in GeB seedlings and the surrounding soil increased, and the number of beneficial fungi and bacteria decreased. Pseudomonas sp., Agrobacterium rhizomes, and Herbaspirillum hiltneri were isolated and identified in the first generation, and Trichoderma harzianum, Penicillium viridiatum, Fusarium oxysporum, and Novosphingobium sp. Were isolated and identified in the third generation. Antagonistic strains of the three pathogenic bacterial strains were screened. In conclusion, beneficial bacteria significantly improved the production performance of asexual reproductive seedlings planted with GeB. Discussion: In conclusion, our findings suggested that the microorganisms of GeB seedlings and the surrounding soil change as the number of generations of GeB reproduction increases, disrupts the microecological balance of surrounding soil and endophytic microbiomes.This study provides a theoretical basis for the degradation of asexual reproduction in GeB.

17.
Parasitol Res ; 123(2): 139, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38381180

RESUMO

The flow of calcium ions (Ca2+) is involved in numerous vital activities of Toxoplasma gondii. Calreticulin is a type of Ca2+-binding protein in the endoplasmic reticulum (ER) that is involved in Ca2+ signaling pathway regulation, Ca2+ storage, and protein folding. In this work, the calreticulin (CALR), a protein predicted to possess a conserved domain of calreticulin in T. gondii, was characterized. The CALR localized in the ER. Using reverse genetics, we discovered that CALR is not necessary for the lytic cycle, including invasion and replication. However, depletion of CALR affected microneme secretion triggered by A23187, which is a Ca2+ ionophore used to increase cytoplasmic Ca2+ concentration. Furthermore, we discovered that CALR influences Ca2+ release. Transcriptomic comparison between Δcalr and Δku80 parasites showed that 226 genes in the Δcalr parasites were significantly downregulated (p < 0.05). The cellular biological functions of the downregulated genes were mainly involved in calmodulin-dependent protein kinase pathways. Furthermore, in the absence of CALR, tachyzoites were still able to cause acute infection in mice. These results imply that by influencing ER Ca2+ release content, CALR may further impair the ionophore-induced secretion of the parasite. However, this protein is not required for the completion of the parasite's lytic cycle or for the acute virulence of the parasite.


Assuntos
Toxoplasma , Animais , Camundongos , Toxoplasma/genética , Calreticulina/genética , Micronema , Retículo Endoplasmático , Ionóforos
18.
IEEE Trans Image Process ; 33: 1710-1725, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38416622

RESUMO

Deep learning has excelled in single-image super-resolution (SISR) applications, yet the lack of interpretability in most deep learning-based SR networks hinders their applicability, especially in fields like medical imaging that require transparent computation. To address these problems, we present an interpretable frequency division SR network that operates in the image frequency domain. It comprises a frequency division module and a step-wise reconstruction method, which divides the image into different frequencies and performs reconstruction accordingly. We develop a frequency division loss function to ensure that each reconstruction module (ReM) operates solely at one image frequency. These methods establish an interpretable framework for SR networks, visualizing the image reconstruction process and reducing the black box nature of SR networks. Additionally, we revisited the subpixel layer upsampling process by deriving its inverse process and designing a displacement generation module. This interpretable upsampling process incorporates subpixel information and is similar to pre-upsampling frameworks. Furthermore, we develop a new ReM based on interpretable Hessian attention to enhance network performance. Extensive experiments demonstrate that our network, without the frequency division loss, outperforms state-of-the-art methods qualitatively and quantitatively. The inclusion of the frequency division loss enhances the network's interpretability and robustness, and only slightly decreases the PSNR and SSIM metrics by an average of 0.48 dB and 0.0049, respectively.

19.
Am J Pathol ; 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38417697

RESUMO

Ferroptosis is a new form of cell death characterized by iron-dependent lipid peroxidation. Whether ferroptosis is involved in retinal microvascular dysfunction under diabetic condition is not known. The expression of ferroptosis-related genes in patients with proliferative diabetic retinopathy and in diabetic mice was determined with RT-qPCR. Reactive oxygen species, iron content, lipid peroxidation products, and ferroptosis-associated proteins in the cultured human retinal microvascular endothelial cells (HRMECs) and in the retina of diabetic mice were examined. The association of ferroptosis with the functions of endothelial cells in vitro was evaluated. After administration of ferroptosis-specific inhibitor, Fer-1, the retinal microvasculature in diabetic mice was assessed. Characteristic changes of ferroptosis-associated markers, including GPX4, FTH1, long-chain acyl-CoA synthetase 4, TFRC, and cyclooxygenase-2, were detected in the retinal fibrovascular membrane of patients with proliferative diabetic retinopathy, cultured HRMECs, and the retina of diabetic mice. Elevated levels of reactive oxygen species, lipid peroxidation, and iron content were found in the retina of diabetic mice and in cultured HRMECs. Ferroptosis was found to be associated with HRMEC dysfunction under high-glucose condition. Inhibition of ferroptosis with specific inhibitor Fer-1 in diabetic mice significantly reduced the severity of retinal microvasculopathy. Ferroptosis contributes to microvascular dysfunction in diabetic retinopathy, and inhibition of ferroptosis might be a promising strategy for the therapy of early-stage diabetic retinopathy.

20.
J Colloid Interface Sci ; 661: 501-511, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38308890

RESUMO

Metal-organic framework materials (MOFs) and their derivatives have been widely used in the field of photocatalytic water decomposition for hydrogen production. In this study, NiS/CdS was initially acquired and subsequently combined with DUT-67 via ultrasound to create a unique ternary photocatalyst NiS/CdS@DUT-67. The rate of hydrogen production for NiS/CdS@DUT-67 is 9618 µmol·g NiS/CdS-1·h-1 for NiS/CdS@DUT-67, which is 32 times and 2.5 times higher than that for CdS and NiS/CdS, respectively. Of particular interest is the fact that even after 50 h of photocatalysis, the hydrogen production rate did not show a significant decrease, demonstrating its excellent stability compared to CdS and NiS/CdS. In this ternary system, NiS and DUT-67 function as dual co-catalysts for CdS, collaborating to enhance charge separation during the photocatalysis. This study presents a clear demonstration of the advantages of utilizing metal-organic framework derivatives (MOF-derivatives) cophotocatalysts and their synergistic effect, resulting in improved photocatalytic activity and stability of semiconductors. This innovative approach provides a new perspective on constructing photocatalytic materials with exceptional performance.

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