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1.
Int Immunopharmacol ; 130: 111778, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38432147

RESUMO

OBJECTIVE: To investigate the mechanism of action of fatty acid receptors, FFAR1 and FFAR4, on ulcerative colitis (UC) through fatty acid metabolism and macrophage polarization. METHODS: Dextran sulfate sodium (DSS)-induced mouse model of UC mice was used to evaluate the efficacy of FFAR1 (GW9508) and FFAR4 (GSK137647) agonists by analyzing body weight, colon length, disease activity index (DAI), and histological scores. Real-time PCR and immunofluorescence analysis were performed to quantify the levels of fatty acid metabolizing enzymes and macrophage makers. FFA-induced lipid accumulation in RAW264.7 cells was visualized by Oil Red O staining analysis, and cells were collected to detect macrophage polarization by flow cytometry. RESULTS: The combination of GW9508 and GSK137647 significantly improved DSS-induced UC symptoms, caused recovery in colon length, and decreased histological injury. GW9508 + GSK137647 treatment upregulated the expressions of CD206, lipid oxidation enzyme (CPT-1α) and anti-inflammatory cytokines (IL-4, IL-10, IL-13) but downregulated those of CD86, lipogenic enzymes (ACC1, FASN, SCD1), and pro-inflammatory cytokines (IL-1ß, IL-6, TNF-α). Combining the two agonists decreased FFA-induced lipid accumulation and increased CD206 expression in cell-based experiments. CONCLUSION: Activated FFAR1 and FFAR4 ameliorates DSS-induced UC by promoting fatty acid metabolism to reduce lipid accumulation and mediate M2 macrophage polarization.


Assuntos
Colite Ulcerativa , Ácidos Graxos não Esterificados , Macrófagos , Receptores Acoplados a Proteínas G , Animais , Camundongos , Compostos de Anilina/farmacologia , Compostos de Anilina/uso terapêutico , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/tratamento farmacológico , Colo/patologia , Citocinas/metabolismo , Sulfato de Dextrana , Modelos Animais de Doenças , Ácidos Graxos não Esterificados/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Metilaminas/farmacologia , Metilaminas/uso terapêutico , Camundongos Endogâmicos C57BL , Propionatos/farmacologia , Propionatos/uso terapêutico , Sulfonamidas/farmacologia , Sulfonamidas/uso terapêutico , Receptores Acoplados a Proteínas G/agonistas
4.
Curr Protoc ; 4(1): e982, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38270535

RESUMO

Alpha-1,6 core fucosylation (CF) is a unique glycoform of N-glycans, and studies showed that CF modifications are involved in the occurrence and progression of various diseases and may provide potential disease biomarkers. Current strategies for the CF glycoproteome are often based on multistep enrichment of glycoproteins or glycopeptides and sequential cleavage with different glycosidases to truncate the N-glycans. Although the detection ability of low-abundance glycoproteins is improved, sample loss, high cost, and the time-consuming multistep operation also affect the reproducibility of results and the practicality of the method. Here we developed a single-step truncation (SST) strategy and evaluated its potential for the CF glycoproteome of human serum. The SST strategy has the advantages of fewer operational steps, lower cost, higher number of identifications, and better quantitative stability compared with previous approaches and provides an efficient solution for large-scale quantitative analysis of the CF glycoproteome. © 2024 Wiley Periodicals LLC. Basic Protocol 1: Single-step truncation strategy for core fucosylation glycoproteome analysis in human serum Basic Protocol 2: Liquid chromatography-tandem mass spectrometry quantification of site-specific core fucosylation glycopeptides Alternate Protocol: Pretreatment of cellular samples of core fucosylation glycoproteome with single-step truncation strategy.


Assuntos
Glicopeptídeos , Glicoproteínas , Humanos , Reprodutibilidade dos Testes , Cromatografia Líquida , Polissacarídeos , Proteoma
5.
Front Genome Ed ; 5: 1289416, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37965302

RESUMO

Parasitic plants pose a significant threat to global agriculture, causing substantial crop losses and hampering food security. In recent years, CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats) gene-editing technology has emerged as a promising tool for developing resistance against various plant pathogens. Its application in combating parasitic plants, however, remains largely unexplored. This review aims to summarise current knowledge and research gaps in utilising CRISPR to develop resistance against parasitic plants. First, we outline recent improvements in CRISPR gene editing tools, and what has been used to combat various plant pathogens. To realise the immense potential of CRISPR, a greater understanding of the genetic basis underlying parasitic plant-host interactions is critical to identify suitable target genes for modification. Therefore, we discuss the intricate interactions between parasitic plants and their hosts, highlighting essential genes and molecular mechanisms involved in defence response and multilayer resistance. These include host resistance responses directly repressing parasitic plant germination or growth and indirectly influencing parasitic plant development via manipulating environmental factors. Finally, we evaluate CRISPR-mediated effectiveness and long-term implications for host resistance and crop improvement, including inducible resistance response and tissue-specific activity. In conclusion, this review highlights the challenges and opportunities CRISPR technology provides to combat parasitic plants and provides insights for future research directions to safeguard global agricultural productivity.

7.
Glycoconj J ; 40(5): 541-549, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37542637

RESUMO

Alpha-1,6 fucosylation of N-glycans (core fucosylation, CF) represents a unique form of N-glycans and is widely involved in disease progression. In order to accurately identify CF glycoproteins, several approaches have been developed based on sequential cleavage with different glycosidases to truncate the N-glycans. Since multi-step sample treatments may introduce quantitation bias and affect the practicality of these approaches in large-scale applications. Here, we systematically evaluated the performance of the single-step treatment of intact glycopeptides by endoglycosidase F3 for CF glycoproteome. The single-step truncation (SST) strategy demonstrated higher quantitative stability and higher efficiency compared with previous approaches. The strategy was further practiced on both cell lines and serum samples. The dysregulation of CF glycopeptides between preoperative and postoperative serum from patients with pancreatic ductal adenocarcinoma was revealed, and the CF modifications of BCHE_N369, CDH5_N112 and SERPIND1_N49 were found to be potential prognostic markers. This study thus provides an efficient solution for large-scale quantitative analysis of the CF glycoproteome.


Assuntos
Glicopeptídeos , Glicoproteínas , Humanos , Glicosilação , Glicoproteínas/metabolismo , Glicopeptídeos/análise , Polissacarídeos
8.
JAMA Netw Open ; 6(8): e2325000, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37578798

RESUMO

This case series investigates whether analysis of clinical history via a language model system improves diagnostic accuracy in patients with complex and delayed diagnoses.


Assuntos
Diagnóstico Tardio , Prontuários Médicos , Humanos , Pacientes
9.
Poult Sci ; 102(6): 102622, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37019074

RESUMO

The anti-inflammatory role of lutein has been widely recognized, however, the underlying mechanism is still not fully elucidated. Hence, the effects of lutein on the intestinal health and growth performance of broilers and the action of mechanism were investigated. 288 male yellow-feathered broilers (1-day old) were randomly allocated to 3 treatment groups with 8 replicates of 12 birds each, and the control group was fed a broken rice-soybean basal diet, while the test groups were fed a basal diet added with 20 mg/kg and 40 mg/kg of lutein (LU20, LU40), respectively. The feeding trial lasted for 21 d. The results showed that 40 mg/kg lutein supplementation tended to increase ADFI (P = 0.10) and ADG (P = 0.08) of broilers. Moreover, the addition of lutein caused a decreasing trend of gene expression and concentration of proinflammatory cytokines IL-1ß (P = 0.08, P = 0.10, respectively) and IL-6 (P = 0.06, P = 0.06, respectively) and also tended to decrease the gene expression of TLR4 (P = 0.09) and MyD88 (P = 0.07) while increasing gene expression and concentration of anti-inflammatory cytokines IL-4 and IL-10 (P < 0.05) in the jejunum mucosa of broilers. Additionally, lutein supplementation increased the jejunal villi height of broilers (P < 0.05) and reduced villi damage. The experiment in vitro showed that lutein treatment reduced the gene expression of IL-1ß, IL-6, and IFN-γ in chicken intestinal epithelial cells (P < 0.05). However, this effect was diminished after knock-down of TLR4 or MyD88 genes using RNAi technology. In conclusion, lutein can inhibit the expression and secretion of proinflammatory cytokines in the jejunum mucosa and promote intestinal development of broilers, and the anti-inflammatory effect may be achieved by regulating TLR4/MyD88 signaling pathway.


Assuntos
Galinhas , Receptor 4 Toll-Like , Masculino , Animais , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismo , Galinhas/fisiologia , Fator 88 de Diferenciação Mieloide , Luteína/farmacologia , Luteína/metabolismo , Interleucina-6/metabolismo , Dieta/veterinária , Transdução de Sinais , Citocinas/metabolismo , Diferenciação Celular , Ração Animal/análise
10.
J Ethnopharmacol ; 311: 116430, 2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-36997133

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Huangqin Decoction (HQD), a traditional Chinese medicine (TCM) formula chronicled in Shang Han Lun, is safe and effective for treatment of ulcerative colitis (UC). AIM OF THE STUDY: To investigate the effect of HQD against dextran sulfate sodium (DSS)-induced UC mice by regulating gut microbiota and metabolites, and further explore the mechanism of fatty acid metabolism on macrophage polarization. MATERIALS AND METHODS: Based on 3% dextran sulfate sodium (DSS)-induced UC mice model, clinical symptoms observation (body weight, DAI, and colon length) and histological inspection were used to evaluate the efficacy of HQD and fecal microbiota transplantation (FMT) from HQD-treated mice. The gut microbiota and metabolites were detected by 16S rRNA sequencing and metabolomics analysis. The parameters of fatty acid metabolism, macrophage polarization, and FFAR1/FFAR4-AMPK-PPARα pathway were analyzed by immunofluorescence analysis, western blotting, and real-time PCR. Then, the effects of FFAR1 and FFAR4 on macrophage polarization were examined by agonists based on LPS-induced RAW264.7 cell model. RESULTS: The results showed that FMT, like HQD, ameliorated UC by improving weight loss, restoring colon length, and reducing DAI scores and histopathological scores. Besides, HQD and FMT both enhanced the richness of gut microbiota, and modulated intestinal bacteria and metabolites to achieve a new balance. Untargeted metabolomics analysis revealed that fatty acids, especially long-chain fatty acids (LCFAs), dominated in HQD against DSS-induced UC by regulating the gut microenvironment. Further, FMT and HQD recovered the expression of fatty acid metabolism-related enzymes, and simultaneously activated FFAR1/FFAR4-AMPK-PPARα pathway but suppressed NF-κB pathway. Combined with cell experiment, HQD and FMT promoted macrophage polarization from M1 toward M2, which were well associated with anti-inflammatory cytokines and combined with the activated FFAR4. CONCLUSIONS: The mechanism of HQD against UC was related to regulating fatty acid metabolism to mediate M2 macrophage polarization by activating the FFAR4-AMPK-PPARα pathway.


Assuntos
Colite Ulcerativa , Colite , Animais , Camundongos , PPAR alfa/genética , Proteínas Quinases Ativadas por AMP , Scutellaria baicalensis , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/tratamento farmacológico , Sulfato de Dextrana/toxicidade , RNA Ribossômico 16S , Colo , Modelos Animais de Doenças , Ácidos Graxos , Camundongos Endogâmicos C57BL
11.
PLoS Biol ; 21(3): e3001982, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36917569

RESUMO

Our current food production systems are unsustainable, driven in part through the application of chemically fixed nitrogen. We need alternatives to empower farmers to maximise their productivity sustainably. Therefore, we explore the potential for transferring the root nodule symbiosis from legumes to other crops. Studies over the last decades have shown that preexisting developmental and signal transduction processes were recruited during the evolution of legume nodulation. This allows us to utilise these preexisting processes to engineer nitrogen fixation in target crops. Here, we highlight our understanding of legume nodulation and future research directions that might help to overcome the barrier of achieving self-fertilising crops.


Assuntos
Fabaceae , Fixação de Nitrogênio , Fixação de Nitrogênio/fisiologia , Fabaceae/fisiologia , Simbiose , Produtos Agrícolas
12.
Int Orthop ; 47(4): 1041-1049, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36680634

RESUMO

PURPOSE: To determine whether avascular necrosis can affect clinical outcomes or the union incidence after arthroscopic bone grafting for the treatment of scaphoid nonunion. METHODS: This retrospective comparative study included thirty-four patients with scaphoid nonunion that underwent arthroscopic bone graft from the ipsilateral radius and internal fixation. The patients were divided into two cohorts (group A, with avascular necrosis, n = 15; group B, without avascular necrosis, n = 19) based on pre-operative magnetic resonance imaging findings. Additionally, the patients were grouped in accordance with the location of nonunion (waist, n = 27; proximal pole, n = 7). The mean follow-up was 20.7 months (range 12.0-40.0 months). Clinical outcomes, including the visual analog scale (VAS) pain score, grip strength, range of motion (ROM), Mayo Wrist Score (MWS), and Disabilities of the Arm, Shoulder, and Hand (DASH) score, were evaluated. Radiographic measurements for carpal bone alignment were assessed as well. RESULTS: Union rates did not differ between groups (group A, 93.3%; group B, 94.7%: p = 0.863), and the post-operative VAS pain score, ROM, and MWS were similar at follow-up for a minimum of one year. DASH and grip strength were significantly better in group B, but the intergroup differences were minimal (mean DASH 11.9 versus 9.6; mean grip strength 77.5% versus 95.4% of contralateral side). There was no significant intergroup difference in mean time to achieving union (group A, 14.9 weeks; group B, 14.6 weeks; p = 0.900). In post-operative radiographic assessments, no significant intergroup differences were noted in any of the parameters. Subgroup analysis regarding the location of nonunion showed there were no significant intergroup differences in union rates, mean time to achieving union, and clinical outcome measures at the last post-operative follow-up. CONCLUSIONS: Arthroscopic bone grafting and internal fixation in the treatment of scaphoid nonunion provided good union rates and satisfactory outcomes regardless of vascularity status.


Assuntos
Fraturas não Consolidadas , Osteonecrose , Osso Escafoide , Humanos , Rádio (Anatomia)/diagnóstico por imagem , Rádio (Anatomia)/cirurgia , Estudos Retrospectivos , Transplante Ósseo/métodos , Osso Escafoide/diagnóstico por imagem , Osso Escafoide/cirurgia , Fixação Interna de Fraturas/efeitos adversos , Fixação Interna de Fraturas/métodos , Parafusos Ósseos , Osteonecrose/diagnóstico por imagem , Osteonecrose/cirurgia , Amplitude de Movimento Articular , Fraturas não Consolidadas/diagnóstico por imagem , Fraturas não Consolidadas/cirurgia , Dor , Resultado do Tratamento
13.
Chem Biol Drug Des ; 101(3): 605-613, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36178076

RESUMO

This study aims to investigate cordycepin's effects on the proliferation, migration, and invasion of retinoblastoma (RB) cells and its regulatory mechanism. In this study, it was found that cordycepin inhibited RB cell proliferation, migration, and invasion in vitro, and pulmonary metastasis in vivo. c-Myc was a downstream target of cordycepin, and cordycepin significantly suppressed c-Myc expression, and c-Myc overexpression markedly counteracted the impacts of cordycepin on RB cell proliferation, migration, and invasion. c-Myc was positively correlated with the cell cycle pathway. Cordycepin restrained cyclin D1 expression, and c-Myc overexpression rescued this effect. In conclusion, cordycepin targets the c-Myc/cyclin D1 pathway, thereby suppressing the malignant biological behaviors of RB cells.


Assuntos
Neoplasias Pulmonares , Neoplasias da Retina , Retinoblastoma , Humanos , Ciclina D1 , Retinoblastoma/tratamento farmacológico , Retinoblastoma/metabolismo , Retinoblastoma/patologia , Proliferação de Células , Neoplasias Pulmonares/tratamento farmacológico , Linhagem Celular Tumoral , Movimento Celular
14.
Chinese Critical Care Medicine ; (12): 554-557, 2023.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-982632

RESUMO

Compared with conventional cardiopulmonary resuscitation (CCPR), extracorporeal cardiopulmonary resuscitation (ECPR) can improve the survival rate of patients with cardiac arrest, and reduce the risk of reperfusion injury. However, it is still difficult to avoid the risk of secondary brain damage. Low temperature management has good neuroprotective potential for ECPR patients, which minimizes brain damage. However, unlike CCPR, ECPR has no clear prognostic indicator. The relationship between ECPR combined with hypothermia management-related treatment measure and neurological prognosis is not clear. This article reviews the effect of ECPR combined with different therapeutic hypothermia on brain protection and provides a reference for the prevention and treatment of neurological injury in patients with ECPR.


Assuntos
Humanos , Encéfalo , Reanimação Cardiopulmonar , Lesões Encefálicas , Hipotermia Induzida , Parada Cardíaca
15.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-981444

RESUMO

Ajania belonging to the subtribe Artemisiinae of Anthemideae(Asteraceae) is a genus of semi-shrubs closely related to Chrysanthemum. There are 24 species of Ajania in northwestern China, most of which are folk herbal medicines with strong stress tolerance. Modern medical studies have demonstrated that the chemical constituents of Ajania mainly include terpenoids, flavonoids, phenylpropanoids, alkynes, and essential oils. These compounds endow the plants with antimicrobial, anti-inflammatory, antitumor, antimalarial, antioxidant, and insecticide effects. In this study, we reviewed the research progress in the chemical constituents and pharmacological activities of Ajania, aiming to provide reference for the further research and development of Ajania.


Assuntos
Asteraceae , Chrysanthemum , Alcinos , Antimaláricos , Antioxidantes/farmacologia
16.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-971381

RESUMO

OBJECTIVES@#Gastric cancer is a common cancer of the digestive system. Long non-coding RNA (lncRNA) plays an important role in the formation and development of gastric cancer. This study aims to investigate the effect of long non-coding lncRNA 114227 on biologic behaviors in gastric cancer cells.@*METHODS@#The experiment was divided into 4 groups: a negative control (NC) group, a lncRNA 114227 small interference (si-lncRNA 114227) group, an empty vector (Vector) group, and an overexpression vector (OE-lncRNA 114227) group. The expressions of lncRNA 114227 in gastric mucosa and gastric cancer tissues, gastric mucosal epithelial cells and different gastric cancer strains were determined by real-time reverse transcription PCR (real-time RT-PCR).The proliferation were detected by CCK-8 assay in gastric cancer cells. The epithelial-mesenchymal transformation (EMT) was utilized by Transwell assay, scratch healing assay, and Western blotting in gastric cancer cells. The effect of lncRNA 114227 on proliferation of gastric cancer cells was detected by tumor bearing experiment in nude mice in vivo.@*RESULTS@#The expression level of lncRNA 114227 in the gastric cancer tissues was significantly lower than that in the gastric mucosa tissues, and in 4 kinds of gastric cancer strains was all significantly lower than that in gastric mucosal epithelial cells (all P<0.01). In vitro, the proliferation and migration abilities of gastric cells were significantly reduced after overexpressing lncRNA 114227, and cell proliferation and migration were enhanced after silencing lncRNA 114227 (all P<0.05). The results of in vivo subcutaneous tumorigenesis in nude mice showed that the tumorigenic volume of the tumor-bearing mice in the OE-lncRNA 114227 group was significantly smaller than that of the Vector group, and the tumorigenic quality was lower than that of the Vector group (P<0.05), indicating that lncRNA 114227 inhibited tumorigenesis.@*CONCLUSIONS@#The expression of lncRNA 114227 is downregulated in gastric cancer gastric cancer tissues and cell lines. LncRNA 114227 may inhibit the proliferation and migration of gastric cancer cells through EMT process.


Assuntos
Animais , Camundongos , RNA Longo não Codificante/metabolismo , Neoplasias Gástricas/patologia , Camundongos Nus , Linhagem Celular Tumoral , Proliferação de Células/genética , Carcinogênese/genética , Movimento Celular/genética , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica , Apoptose/genética
17.
Front Plant Sci ; 13: 1086384, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36578337

RESUMO

Parasitic plants are notorious for causing serious agricultural losses in many countries. Specialized intrusive organs, haustoria, confer on parasitic plants the ability to acquire water and nutrients from their host plants. Investigating the mechanism involved in haustorium development not only reveals the fascinating mystery of how autotrophic plants evolved parasitism but also provides the foundation for developing more effective methods to control the agricultural damage caused by parasitic plants. Cuscuta species, also known as dodders, are one of the most well-known and widely spread stem holoparasitic plants. Although progress has been made recently in understanding the evolution and development of haustoria in root parasitic plants, more and more studies indicate that the behaviors between root and stem haustorium formation are distinct, and the mechanisms involved in the formation of these organs remain largely unknown. Unlike most endoparasites and root holoparasitic plants, which have high host-specificity and self- or kin-recognition to avoid forming haustoria on themselves or closely related species, auto-parasitism and hyper-parasitism are commonly observed among Cuscuta species. In this review, we summarize the current understanding of haustorium development in dodders and the unique characteristics of their parasitizing behaviors. We also outline the advantages of using Cuscuta species as model organisms for haustorium development in stem holoparasitic plants, the current unknown mysteries and limitations in the Cuscuta system, and potential future research directions to overcome these challenges.

18.
BMC Musculoskelet Disord ; 23(1): 957, 2022 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-36333815

RESUMO

BACKGROUND: Angular stable locking plates have shown good clinical results in treating proximal humeral fractures, but complications are not uncommon. This study reported a rare case of catastrophic failure of a titanium locking plate. A retrieval analysis of the implants was performed using an optic microscope and a scanning electron microscope. CASE PRESENTATION: A 69-year-old male reported a right proximal humeral fracture at the surgical neck and was treated by open reduction and internal fixation with a locking plate system. Ninety-six days after surgery, the patient came to clinic for acute local pain over the shoulder without any trauma. The radiographs showed a complete breakage of the implant accompanying displaced fracture. Revision surgery was performed to restabilize the fracture with a longer locking plate. The follow-up radiographs at 9 months showed complete union of the bone fracture. CONCLUSIONS: From the retrieval analysis, repetitive torsion loads on the vulnerable area of the implant are assumed to cause this catastrophic event. It is recommended that adequate activity restriction, such as reaching, be undertaken to avoid this rare complication. Current study also provides contributive information for the modification of plate design and pre-operative planning for device configuration to improve the success rate of locking plate fixation.


Assuntos
Fraturas do Ombro , Titânio , Masculino , Humanos , Idoso , Fraturas do Ombro/diagnóstico por imagem , Fraturas do Ombro/cirurgia , Placas Ósseas/efeitos adversos , Fixação Interna de Fraturas/métodos , Redução Aberta , Resultado do Tratamento
19.
J Control Release ; 351: 847-859, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36206946

RESUMO

Conductive polymers have been investigated as a medium for the transmission of electrical signals in biological tissues, but their capacity to rewire cardiac tissue has not been evaluated. Myocardial tissue is unique in being able to generate an electrical potential at a fixed rate; this potential spreads rapidly among cells to trigger muscle contractions. Tissue injuries result in myocardial fibrosis and subsequent non-uniform conductivity, leading to arrhythmia. Atrial fibrillation (AF) is the most common sustained arrhythmia, associated with disruption of atrial electrical signaling, which can potentially be restored by the epicardial delivery of conductive polymers. In this work, poly-3-amino-4-methoxybenzoic acid, conjugated to gelatin, is fabricated as a membrane (PAMB-G) to support conductive velocities that are close to that of the myocardium. A cross-linked gelatin membrane (Gelatin) is used as a control. The as-fabricated PAMB-G has similar tensile elasticities, determined using the Young's modulus, as contracting myocardium; it can also transmit electrical signals to initiate cardiac cell and tissue excitation. Delivering PAMB-G onto the atrium of a rat AF model shortens AF duration and improves post-AF recovery for the duration of a 28-day-long study. Atrial tissue in the PAMB-G-implanted group has lower impedance, higher conduction velocity, and higher field potential amplitude than that in the Gelatin-implanted group. Therefore, the as-proposed PAMB-G is a suitable medium for restoring proper cardiac electrical signaling in AF hearts.


Assuntos
Fibrilação Atrial , Ratos , Animais , Fibrilação Atrial/tratamento farmacológico , Gelatina , Átrios do Coração , Frequência Cardíaca , Polímeros
20.
Annu Rev Plant Biol ; 73: 433-455, 2022 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-35363532

RESUMO

In contrast to most autotrophic plants, which produce carbohydrates from carbon dioxide using photosynthesis, parasitic plants obtain water and nutrients by parasitizing host plants. Many important crop plants are infested by these heterotrophic plants, leading to severe agricultural loss and reduced food security. Understanding how host plants perceive and resist parasitic plants provides insight into underlying defense mechanisms and the potential for agricultural applications. In this review, we offer a comprehensive overview of the current understanding of host perception of parasitic plants and the pre-attachment and post-attachment defense responses mounted by the host. Since most current research overlooks the role of organ specificity in resistance responses, we also summarize the current understanding and cases of cross-organ parasitism, which indicates nonconventional haustorial connections on other host organs, for example, when stem parasitic plants form haustoria on their host roots. Understanding how different tissue types respond to parasitic plants could provide the potential for developing a universal resistance mechanism in crops against both root and stem parasitic plants.


Assuntos
Parasitos , Animais , Produtos Agrícolas/parasitologia , Interações Hospedeiro-Parasita/fisiologia , Simbiose
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