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1.
Artigo em Inglês | MEDLINE | ID: mdl-38863365

RESUMO

OBJECTIVES: Pseudomonas aeruginosa and Acinetobacter baumannii are ranked as top-priority organisms by WHO. Antimicrobial peptides (AMPs) are promising antimicrobial agents that are highly effective against serious bacterial infections. METHODS: In our previous study, a series of α-helical AMPs were screened using a novel multiple-descriptor strategy. The current research suggested that S24 exhibited strong antimicrobial activity against major pathogenic bacteria, and displayed minimal haemolysis, good serum stability and maintained salt resistance. RESULTS: We found that S24 exerted an antimicrobial effect by destroying outer membrane permeability and producing a strong binding effect on bacterial genomic DNA that inhibits genomic DNA migration. Furthermore, S24 exerted a strong ability to promote healing in wound infected by P. aeruginosa, A. baumannii and mixed strains in a mouse model. CONCLUSIONS: Overall, S24 showed good stability under physiological conditions and excellent antimicrobial activity, suggesting it may be a potential candidate for the development of serious bacterial infection treatment.

2.
Int J Biol Macromol ; 267(Pt 2): 131578, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38641267

RESUMO

The impact of Dielectric-Barrier Discharge (DBD) plasma treatment on the prevention of heat-induced aggregation of Ovalbumin (OVA) and improvement in emulsification properties was investigated. Results highlighted the effective inhibition of thermal aggregation of OVA following exposure to plasma. Structural analysis revealed that the plasma-induced oxidation of sulfhydryl and intermolecular disulfide bonds played a pivotal role in inhibiting the thermal aggregation, considered by Sodium Dodecyl Sulfate Polyacrylamide Gel Electrophoresis (SDS-PAGE), multiplies spectroscopy, and analysis of dynamic exchange of sulfhydryl-disulfide bonds. Meanwhile, the oxidation of exposed hydrophobic sites due to plasma treatment resulted in the transformation of the OVA molecule's surface from hydrophobic to hydrophilic, contributing significantly to the aggregation inhibition. Additionally, compared to an untreated sample of OVA, almost one-fold increase in emulsifying ability (EAI) and 1.5-fold in emulsifying stability (ESI) was observed after 4 min of plasma treatment. These findings demonstrated that plasma treatment not only enhanced the thermal stability of OVA, but also improved its emulsification properties.


Assuntos
Emulsões , Interações Hidrofóbicas e Hidrofílicas , Ovalbumina , Gases em Plasma , Animais , Emulsões/química , Temperatura Alta , Ovalbumina/química , Oxirredução , Gases em Plasma/química , Agregados Proteicos , Feminino , Galinhas
3.
Hypertens Res ; 47(5): 1273-1287, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38438725

RESUMO

m6A (N6­methyladenosine) is the most common and abundant apparent modification in mRNA of eukaryotes. The modification of m6A is regulated dynamically and reversibly by methyltransferase (writer), demethylase (eraser), and binding protein (reader). It plays a significant role in various processes of mRNA metabolism, including regulation of transcription, maturation, translation, degradation, and stability. Pulmonary arterial hypertension (PAH) is a malignant cardiopulmonary vascular disease characterized by abnormal proliferation of pulmonary artery smooth muscle cells. Despite the existence of several effective and targeted therapies, there is currently no cure for PAH and the prognosis remains poor. Recent studies have highlighted the crucial role of m6A modification in cardiovascular diseases. Investigating the role of RNA m6A methylation in PAH could provide valuable insights for drug development. This review aims to explore the mechanism and function of m6A in the pathogenesis of PAH and discuss the potential targeting of RNA m6A methylation modification as a treatment for PAH.


Assuntos
Adenosina , Adenosina/análogos & derivados , Hipertensão Arterial Pulmonar , Humanos , Metilação , Adenosina/metabolismo , Hipertensão Arterial Pulmonar/genética , Hipertensão Arterial Pulmonar/metabolismo , Animais , RNA Mensageiro/metabolismo , RNA Mensageiro/genética , Metiltransferases/metabolismo , Metiltransferases/genética , Metilação de RNA
4.
Artigo em Inglês | MEDLINE | ID: mdl-38243974

RESUMO

OBJECTIVE: To investigate the effect of high blood glucose on the decline in the estimated glomerular filtration rate (eGFR) in the elderly. METHODS: We compared the decline in eGFR of diabetic and non-diabetic groups in the noninterventional state and analyzed the effect of hyperglycemia on the decline in eGFR among the elderly in a retrospective analysis of 1,223 cases of elderly people aged 65 years or older with a 4-year follow-up period. RESULTS: The prevalence of diabetes in the elderly increased significantly from 12.67% in 2017 to 16.68% in 2021. The rate of decline in eGFR in patients with diabetes was higher than in the population without diabetes, at 9.29% and 5.32%, respectively (both p <0.05). CONCLUSION: The results of this study revealed that the prevalence of diabetes in the elderly increased significantly, and there is a more rapid decrease in the eGFR levels in those with diabetes than those without diabetes.

5.
ACS Appl Mater Interfaces ; 15(51): 59964-59972, 2023 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-38085261

RESUMO

Planar defects are known to be of importance in affecting the functional properties of materials. Translational antiphase boundaries (APBs) in particular have attracted considerable attention in perovskite oxides, but little is known in lead-free antiferroelectric oxides that are promising candidates for energy storage applications. Here, we present a study of translational APBs in prototypical antiferroelectric NaNbO3 using aberration-corrected (scanning) transmission electron microscopy (TEM) techniques at different length scales. The translational APBs in NaNbO3 are characterized by a 2-fold-modulated structure, which is antipolar in nature and exhibits a high density, different from the polar nature and lower density in PbZrO3. The high stability of translational APBs against external electric fields and elevated temperatures was revealed using ex situ and in situ TEM experiments and is expected to be associated with their antipolar nature. Density functional theory calculations demonstrate that translational APBs possess only slightly higher free energy than the antiferroelectric and ferroelectric phase energies with differences of 29 and 33 meV/f.u., respectively, justifying their coexistence down to the nanoscale at room temperature. These results provide a detailed atomistic elucidation of translational APBs in NaNbO3 with antipolar character and stability against external stimuli, establishing the basis of defect engineering of antiferroelectrics for energy storage devices.

6.
World J Gastrointest Surg ; 15(9): 1986-1994, 2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37901732

RESUMO

BACKGROUND: Adenocarcinoma of the esophagogastric junction has a center of origin within 5 cm of the esophagogastric junction. Surgical resection remains the main treatment. A transthoracic approach is recommended for Siewert I adenocarcinoma of the esophagogastric junction and a transabdominal approach is recommended for Siewert III adenocarcinoma of the esophagogastric junction. However, there is a need to determine the optimal surgical approach for Siewert II adenocarcinoma of the esophagogastric junction to improve lung function and the prognosis of patients. AIM: To investigate and compare the surgical effects, postoperative changes in pulmonary function, and prognoses of two approaches to treating combined esophagogastric cancer. METHODS: One hundred and thirty-eight patients with combined esophagogastric cancer treated by general and thoracic surgeries in our hospital were selected. They were divided into group A comprising 70 patients (transabdominal approach) and group B comprising 68 patients (transthoracic approach) based on the surgical approach. The indexes related to surgical trauma, number of removed lymph nodes, indexes of lung function before and after surgery, survival rate, and survival duration of the two groups were compared 3 years after surgery. RESULTS: The duration of surgery, length of hospital stay, and postoperative drainage duration of the patients in group A were shorter than those of the patients in group B, and the volume of blood loss caused by surgery was lower for group A than for group B (P < 0.05). At the one-month postoperative review, the first second, maximum ventilation volume, forceful lung volume, and lung volume values were higher for group A than for group B (P < 0.05). Preoperatively, the QLQ-OES18 scale scores of the patients in group A were higher than those in group B on re-evaluation at 3 mo postoperatively (P < 0.05). The surgical complication rate of the patients in group A was 10.00%, which was lower than that of patients in group B, which was 23.53% (P < 0.05). CONCLUSION: Transabdominal and transthoracic surgical approaches are comparable in treating combined esophagogastric cancer; however, the former results in lesser surgical trauma, milder changes in pulmonary function, and fewer complications.

7.
Pharmacol Ther ; 251: 108541, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37783348

RESUMO

Ischemic stroke occurs when the arteries supplying blood to the brain are narrowed or blocked, inducing damage to brain tissue due to a lack of blood supply. One effective way to reduce brain damage and alleviate symptoms is to reopen blocked blood vessels in a timely manner and reduce neuronal damage. To achieve this, researchers have focused on identifying key cellular signaling pathways that can be targeted with drugs. These pathways include oxidative/nitrosative stress, excitatory amino acids and their receptors, inflammatory signaling molecules, metabolic pathways, ion channels, and other molecular events involved in stroke pathology. However, evidence suggests that solely focusing on protecting neurons may not yield satisfactory clinical results. Instead, researchers should consider the multifactorial and complex mechanisms underlying stroke pathology, including the interactions between different components of the neurovascular unit. Such an approach is more representative of the actual pathological process observed in clinical settings. This review summarizes recent research on the multiple molecular mechanisms and drug targets in ischemic stroke, as well as recent advances in novel therapeutic strategies. Finally, we discuss the challenges and future prospects of new strategies based on the biological characteristics of stroke.


Assuntos
Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Isquemia Encefálica/tratamento farmacológico , Acidente Vascular Cerebral/tratamento farmacológico , Encéfalo/metabolismo , AVC Isquêmico/metabolismo , Transdução de Sinais
8.
Zookeys ; 1166: 155-173, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37333901

RESUMO

The systematics of the potamid freshwater crab Cryptopotamonanacoluthon (Kemp, 1918) is clarified, and its generic position in Sinolapotamon Tai & Sung, 1975, is confirmed based on morphological comparisons, geographical information and phylogenetic analyses. A new species of Sinolapotamon, Sinolapotamoncirratumsp. nov. is described from the Guangxi Zhuang Autonomous Region of China. Sinolapotamoncirratumsp. nov. is distinguished from its congeners by the combination of characters of its carapace, third maxilliped, anterolateral margin, and unique male first gonopod. Phylogenetic analyses based on partial COX1, 16S rRNA and 28S rRNA genes also support the species as new.

9.
World J Gastroenterol ; 29(19): 3040-3047, 2023 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-37274804

RESUMO

BACKGROUND: Hepatitis C infection not only damages the liver but also often accompanies many extrahepatic manifestations. Incidences of pulmonary hypertension (PH) caused by hepatitis C are rare, and incidences of concurrent nephrotic syndrome and polymyositis are even rarer. CASE SUMMARY: Herein we describe the case of a 57-year-old woman who was admitted to our department for intermittent chest tightness upon exertion for 5 years, aggravated with dyspnea for 10 d. After relevant examinations she was diagnosed with PH, nephrotic syndrome, and polymyositis due to chronic hepatitis C infection. A multi-disciplinary recommendation was that the patient should be treated with sildenafil and macitentan in combination and methylprednisolone. During treatment autoimmune symptoms, liver function, hepatitis C RNA levels, and cardiac parameters of right heart catheterization were monitored closely. The patient showed significant improvement in 6-min walking distance from 100 to 300 m at 3-mo follow-up and pulmonary artery pressure drops to 50 mmHg. Long-term follow-up is needed to confirm further efficacy and safety. CONCLUSION: Increasing evidence supports a relationship between hepatitis C infection and diverse extrahepatic manifestations, but it is very rare to have PH, nephrotic syndrome, and polymyositis in a single patient. We conducted a literature review on the management of several specific extrahepatic manifestations of hepatitis C.


Assuntos
Hepatite C , Hipertensão Pulmonar , Síndrome Nefrótica , Polimiosite , Feminino , Humanos , Pessoa de Meia-Idade , Hipertensão Pulmonar/diagnóstico , Hipertensão Pulmonar/tratamento farmacológico , Hipertensão Pulmonar/etiologia , Hepacivirus , Síndrome Nefrótica/diagnóstico , Síndrome Nefrótica/tratamento farmacológico , Síndrome Nefrótica/etiologia , Hepatite C/complicações , Hepatite C/diagnóstico , Hepatite C/tratamento farmacológico , Polimiosite/complicações , Polimiosite/diagnóstico , Polimiosite/tratamento farmacológico
10.
Research (Wash D C) ; 6: 0121, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37223477

RESUMO

Disturbance of the cholinergic system plays a crucial role in the pathological progression of neurological diseases that cause dyskinesia-like behaviors. However, the molecular mechanisms underlying this disturbance remain elusive. Here, we showed that cyclin-dependent kinase 5 (Cdk5) was reduced in cholinergic neurons of midbrain according to the single-nucleus RNA sequencing analysis. Serum levels of CDK5 also decreased in patients with Parkinson's disease accompanied by motor symptoms. Moreover, Cdk5 deficiency in cholinergic neurons triggered paw tremors, abnormal motor coordination, and motor balance deficits in mice. These symptoms occurred along with cholinergic neuron hyperexcitability and increases in the current density of large-conductance Ca2+-activated K+ channels (BK channels). Pharmacological inhibition of BK channels restrained the excessive intrinsic excitability of striatal cholinergic neurons in Cdk5-deficient mice. Furthermore, CDK5 interacted with BK channels and negatively regulated BK channel activity via phosphorylation of threonine-908. Restoration of CDK5 expression in striatal cholinergic neurons reduced dyskinesia-like behaviors in ChAT-Cre;Cdk5f/f mice. Together, these findings indicate that CDK5-induced phosphorylation of BK channels involves in cholinergic-neuron-mediated motor function, providing a potential new therapeutic target for treating dyskinesia-like behaviors arising from neurological diseases.

12.
J Ethnopharmacol ; 312: 116457, 2023 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-37088235

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Panax notoginseng (Burk.) F. H. Chen belongs to the Araliaceae family. It has been used by traditional Chinese people in Northeast Asia for centuries as an antidiabetic, antioxidant, antitumor agent, etc. Endophytic or rhizospheric microorganisms play key roles in plant defense mechanisms, and they are essential in the discovery of pharmaceuticals and valuable new secondary metabolites. In particular, endophytic or rhizospheric microorganisms of traditional medicinal plants. AIM OF THE STUDY: To discover valuable new secondary metabolites from rhizosphere soil Streptomyces sp. SYP-A7185 of P. notoginseng, and to explore potential bioactivities and targets of metabolites protrusive function. MATERIALS AND METHODS: The metabolites were obtained via column chromatography and identified by multiple spectroscopic analyses. The antitumor, antioxidant, antibacterial, and antiglycosidases effects of isolated metabolites were tested using 3-[4,5-dimethythiazol-2-yl]-2,5-diphenyltetazolium bromide (MTT), 2,2-diphenyl-1-picrylhydrazyl (DPPH), 96-well turbidimetric, and α-glucosidase inhibitory assays. The potential antitumor targets were predicted through network pharmacological approaches. The interactions between metabolites and target were verified by molecular docking and biolayer interferometry (BLI) assay. The effects of cancer cells migration were detected through wound healing assays in A549 and MCF-7. Other cellular validation experiments including reverse transcription-quantitative PCR (RT‒qPCR) and western blotting (WB) were used to confirm the hypothesis of network pharmacology. RESULTS: Five different chemotypes of anthraquinone derivatives (1-10), including six new compounds (3, 6-10), were identified from Streptomyces sp. SYP-A7185. Compounds 1-6 and 9 displayed moderate to strong cytotoxicity on five human cancer cell lines (A549, HepG2, MCF-7, MDA-MD-231, and MGC-803). Moreover, matrix metalloproteinase-2 (MMP2) were predicted as a potential antitumor target of metabolites 1-6 and 9 by comprehensive network pharmacology analysis. Later, BLI assays revealed strong intermolecular interactions between MMP2 and antitumor metabolites, and molecular docking results showed the interaction of metabolites 1-6 and 9 with MMP2 was dependent on the crucial amino acid residues of LEU-83, ALA-84, LEU-117, HIS-131, PRO-135, GLY-136, ALA-140, PRO-141, TYR-143, and THR-144. These results implied that metabolites (1-6 and 9) might inhibit cancer cell migration besides cancer cell proliferation. After that, the cell wound healing assay showed that the cell migration processes were also inhibited after the treatments of compounds 1 and 3 in A549 and MCF-7 cells. In addition, the RT‒qPCR and WB results demonstrated that the gene expression levels of MMP2 were decreased after the treatment with compounds 1 and 3 in A549 and MCF-7 cells. Besides, compound 2 displayed moderate antioxidant activity (EC50, 27.43 µM), compounds 3 and 6 exhibited moderate antibacterial activity, and compound 3 inhibited α-glucosidase with an IC50 value of 13.10 µM. CONCLUSIONS: Anthraquinone metabolites, from rhizosphere soil Streptomyces sp. of P. notoginseng, possess antitumor, antioxidant, antibacterial, and antiglycosidase activities. Moreover, metabolites 1 and 3 inhibit cancer cells migration through downregulating MMP2.


Assuntos
Neoplasias , Panax notoginseng , Streptomyces , Humanos , Panax notoginseng/química , Solo/química , Metaloproteinase 2 da Matriz , Streptomyces/química , Rizosfera , Antioxidantes/farmacologia , Simulação de Acoplamento Molecular , alfa-Glucosidases , Células MCF-7 , Movimento Celular , Antraquinonas/farmacologia , Antibacterianos , Neoplasias/tratamento farmacológico
13.
Crit Rev Microbiol ; : 1-14, 2023 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-37074732

RESUMO

Live biotherapeutic product (LBP), a type of biological product, holds promise for the prevention or treatment of metabolic disease and pathogenic infection. Probiotics are live microorganisms that improve the intestinal microbial balance and beneficially affect the health of the host when ingested in sufficient numbers. These biological products possess the advantages of inhibition of pathogens, degradation of toxins, and modulation of immunity. The application of LBP and probiotic delivery systems has attracted great interest to researchers. The initial used technologies for LBP and probiotic encapsulation are traditional capsules and microcapsules. However, the stability and targeted delivery capability require further improved. The specific sensitive materials can greatly improve the delivery efficiency of LBPs and probiotics. The specific sensitive delivery systems show advantages over traditional ones due to their better properties of biocompatibility, biodegradability, innocuousness, and stability. Moreover, some new technologies, including layer-by-layer encapsulation, polyelectrolyte complexation, and electrohydrodynamic technology, show great potential in LBP and probiotic delivery. In this review, novel delivery systems and new technologies of LBPs and probiotics were presented, and the challenges and prospects were explored in specific sensitive materials for LBP and probiotic delivery.

14.
J Hazard Mater ; 453: 131393, 2023 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-37062094

RESUMO

Ultraviolet (UV) irradiation is widely used for wastewater disinfection but suffers from low inactivation rates and can cause photoreactivation of microorganisms. Synergistic disinfection with UV and oxidants is promising for enhancing the inactivation performance. This review summarizes the inactivation effects on representative microorganisms by UV/hydrogen peroxide (H2O2), UV/ozone (O3), UV/persulfate (PS), UV/chlorine, and UV/chlorine dioxide (ClO2). UV synergistic processes perform better than UV or an oxidant alone. UV mainly attacks the DNA or RNA in microorganisms; the oxidants H2O2 and O3 mainly attack the cell walls, cell membranes, and other external structures; and HOCl and ClO2 enter cells and oxidize proteins and enzymes. Free radicals can have strong oxidation effects on cell walls, cell membranes, proteins, enzymes, and even DNA. At similar UV doses, the inactivation rates of Escherichia coli with UV alone, UV/H2O2, UV/O3, UV/PS (peroxydisulfate or peroxymonosulfate), and UV/chlorinated oxidant (chlorine, ClO2, and NH2Cl) range from 2.03 to 3.84 log, 2.62-4.30 log, 4.02-6.08 log, 2.93-5.07 log, and 3.78-6.55 log, respectively. The E. coli inactivation rates are in the order of UV/O3 ≈ UV/Cl2 > UV/PS > UV/H2O2. This order is closely related to the redox potentials of the oxidants and quantum yields of the radicals. UV synergistic disinfection processes inhibit photoreactivation of E. coli in the order of UV/O3 > UV/PS > UV/H2O2. The activation mechanisms and formation pathways of free radicals with different UV-based synergistic processes are presented. In addition to generating HO·, O3 can reduce the turbidity and chroma of wastewater to increase UV penetration, which improves the disinfection performance of UV/O3. This knowledge will be useful for further development of the UV-based synergistic disinfection processes.


Assuntos
Desinfecção , Purificação da Água , Peróxido de Hidrogênio/química , Águas Residuárias , Cloro , Escherichia coli , Oxidantes/química , Oxirredução , Cloretos , Raios Ultravioleta
15.
Expert Rev Vaccines ; 22(1): 315-326, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36945780

RESUMO

INTRODUCTION: Over the last four decades, human immunodeficiency virus type 1 (HIV-1) infection has been a major public health concern. It is acknowledged that an effective vaccine remains the best hope for eliminating the HIV-1 pandemic. The prophylaxis of HIV-1 infection remains a central theme because of the absence of an available HIV-1 vaccine. The inability of conventional delivery strategies to induce potent immunity is a crucial task to overcome and ultimately lead to a major obstacle in HIV-1 vaccine research. AREAS COVERED: The literature search was conducted in the following databases: PubMed, Web of Science, and Embase. Nano-platforms-based vaccines have proven prophylaxis in various diseases for effectively activating the immune system. Nano-vaccines, including non-viral and viral vectored nano-vaccines, are in a position to improve the effectiveness of HIV-1 antigen delivery and enhance the innate and adaptive immune responses against HIV-1. Compared to traditional vaccination strategies, genetic immunization can elicit a long-term immune response to provide protective immunity for HIV-1 prevention. EXPERT OPINION: Research progress on nano-vaccines for gene delivery against HIV-1 was discussed. Vaccine strategies based on nano-platforms that are being applied to stimulate effective HIV-1-specific cellular and humoral immune responses were particularly emphasized.


Assuntos
Vacinas contra a AIDS , Infecções por HIV , HIV-1 , Vacinas Virais , Humanos , Infecções por HIV/prevenção & controle , Imunidade Humoral , Vacinação
16.
Gels ; 9(3)2023 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-36975668

RESUMO

Bacterial infection contributes to the bioburden of wounds, which is an essential factor in determining whether a wound can heal. Wound dressings with antibacterial properties that can promote wound-healing are highly desired for the treatment of chronic wound infections. Herein, we fabricated a simple polysaccharide-based hydrogel dressing encapsulating tobramycin-loaded gelatine microspheres with good antibacterial activity and biocompatibility. We first synthesised long-chain quaternary ammonium salts (QAS) by the reaction of tertiary amines with epichlorohydrin. The amino groups of carboxymethyl chitosan were then conjugated with QAS through the ring-opening reaction and QAS-modified chitosan (CMCS) was obtained. The antibacterial analysis showed that both QAS and CMCS could kill E. coli and S. aureus at relatively low concentrations. QAS with 16 carbon atoms has a MIC of 16 µg/mL for E. coli and 2 µg/mL for S. aureus. A series of formulations of tobramycin-loaded gelatine microspheres (TOB-G) were generated and the best formulation was selected by comparing the characters of the microspheres. The microsphere fabricated by 0.1 mL GTA was selected as the optimal candidate. We then used CMCS, TOB-G, and sodium alginate (SA) to prepare physically crosslinking hydrogels using CaCl2 and investigated the mechanical properties, antibacterial activity, and biocompatibility of the hydrogels. In summary, the hydrogel dressing we produced can be used as an ideal alternative for the management of bacteria-infected wounds.

17.
Neural Regen Res ; 18(4): 908-912, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36204862

RESUMO

Previous studies have shown that ulnar nerve compound muscle action potential recorded by the conventional "belly-tendon" montage does not accurately and completely reflect the action potential of the ulnar nerve dominating the abductor digiti minimi muscle due to the effects of far-field potentials of intrinsic hand muscles. A new method of ulnar nerve compound muscle action potential measurement was developed in 2020, which adjusts the E2 electrode from the distal tendon of the abductor digitorum to the middle of the back of the proximal wrist. This new method may reduce the influence of the reference electrode and better reflect the actual ulnar nerve compound muscle action potential. In this prospective cross-sectional study, we included 64 patients with amyotrophic lateral sclerosis and 64 age- and sex-matched controls who underwent conventional and novel ulnar nerve compound muscle action potential measurement between April 2020 and May 2021 in Peking University Third Hospital. The compound muscle action potential waveforms recorded by the new montage were unimodal and more uniform than those recorded by traditional montage. In the controls, no significant difference in the compound muscle action potential waveforms was found between the traditional montage and new montage recordings. In amyotrophic lateral sclerosis patients presenting with abductor digiti minimi spontaneous activity and muscular atrophy, the amplitude of compound muscle action potential-pE2 was significantly lower than that of compound muscle action potential-dE2 (P < 0.01). Using the new method, damaged axons were more likely to exhibit more severe amplitude decreases than those measured with the traditional method, in particular for patients in early stage amyotrophic lateral sclerosis. In addition, the decline in compound muscle action potential amplitude measured by the new method was correlated with a decrease in Revised Amyotrophic Lateral Sclerosis Functional Rating Scale scores. These findings suggest that the new ulnar nerve compound muscle action potential measurement montage reduces the effects of the reference electrode through altering the E2 electrode position, and that this method is more suitable for monitoring disease progression than the traditional montage. This method may be useful as a biomarker for longitudinal follow-up and clinical trials in amyotrophic lateral sclerosis.

18.
Nat Plants ; 8(12): 1423-1439, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36471048

RESUMO

Although SWI/SNF chromatin remodelling complexes are known to regulate diverse biological functions in plants, the classification, compositions and functional mechanisms of the complexes remain to be determined. Here we comprehensively characterized SWI/SNF complexes by affinity purification and mass spectrometry in Arabidopsis thaliana, and found three classes of SWI/SNF complexes, which we termed BAS, SAS and MAS (BRM-, SYD- and MINU1/2-associated SWI/SNF complexes). By investigating multiple developmental phenotypes of SWI/SNF mutants, we found that three classes of SWI/SNF complexes have both overlapping and specific functions in regulating development. To investigate how the three classes of SWI/SNF complexes differentially regulate development, we mapped different SWI/SNF components on chromatin at the whole-genome level and determined their effects on chromatin accessibility. While all three classes of SWI/SNF complexes regulate chromatin accessibility at proximal promoter regions, SAS is a major SWI/SNF complex that is responsible for mediating chromatin accessibility at distal promoter regions and intergenic regions. Histone modifications are related to both the association of SWI/SNF complexes with chromatin and the SWI/SNF-dependent chromatin accessibility. Three classes of SWI/SNF-dependent accessibility may enable different sets of transcription factors to access chromatin. These findings lay a foundation for further investigation of the function of three classes of SWI/SNF complexes in plants.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Montagem e Desmontagem da Cromatina , Fatores de Transcrição/metabolismo , Cromatina , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Adenosina Trifosfatases/metabolismo
19.
Food Funct ; 13(24): 12632-12647, 2022 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-36416361

RESUMO

Alzheimer's disease (AD) is the leading cause of disabilities in old age and a rapidly growing condition in the elderly population. AD brings significant burden and has a devastating impact on public health, society and the global economy. Thus, developing new therapeutics to combat AD is imperative. Human glutaminyl cyclase (hQC), which catalyzes the formation of neurotoxic pyroglutamate (pE)-modified ß-amyloid (Aß) peptides, is linked to the amyloidogenic process that leads to the initiation of AD. Hence, hQC is an essential target for developing anti-AD therapeutics. Here, we systematically screened and identified hQC inhibitors from natural products by pharmacophore-driven inhibitor screening coupled with biochemical and biophysical examinations. We employed receptor-ligand pharmacophore generation to build pharmacophore models and Phar-MERGE and Phar-SEN for inhibitor screening through ligand-pharmacophore mapping. About 11 and 24 hits identified from the Natural Product and Traditional Chinese Medicine databases, respectively, showed diverse hQC inhibitory abilities. Importantly, the inhibitors TCM1 (Azaleatin; IC50 = 1.1 µM) and TCM2 (Quercetin; IC50 = 4.3 µM) found in foods and plants exhibited strong inhibitory potency against hQC. Furthermore, the binding affinity and molecular interactions were analyzed by surface plasmon resonance (SPR) and molecular modeling/simulations to explore the possible modes of action of Azaleatin and Quercetin. Our study successfully screened and characterized the foundational biochemical and biophysical properties of Azaleatin and Quercetin toward targeting hQC, unveiling their bioactive potential in the treatment of AD.


Assuntos
Doença de Alzheimer , Aminoaciltransferases , Inibidores Enzimáticos , Idoso , Humanos , Doença de Alzheimer/tratamento farmacológico , Peptídeos beta-Amiloides/metabolismo , Ligantes , Simulação de Acoplamento Molecular , Farmacóforo , Quercetina/isolamento & purificação , Quercetina/farmacologia , Aminoaciltransferases/antagonistas & inibidores , Inibidores Enzimáticos/isolamento & purificação , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/uso terapêutico
20.
Histol Histopathol ; 37(8): 723-737, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35417038

RESUMO

Direct reprogramming, whether in vitro or in vivo, has attracted great attention because of its advantages of convenience, short-term conversion, direct targets, no immune rejection, and potential clinical applications. In addition, due to its independence from the pluripotent state, direct programming minimizes some safety concerns associated with the use of human pluripotent stem cells. However, the significant limitations of reprogrammed cells, such as poor proliferative ability, low efficiency, and immature function, need to be addressed before the clinical application potential can be expanded. Here, we review the recent achievements of direct reprogramming in 2D and 3D systems in vitro and in vivo, covering cells derived from the three germ layers from stem/progenitor cells to terminal cells, such as hepatocytes, pancreatic ß cells, cardiomyocytes, endothelial cells, osteoblasts, chondrocytes, neurons, and melanocytes. Combining our lab experiences with current work, we summarize the practical and potential issues that need to be solved and the prospects of strategies for addressing the current dilemmas. Through comprehensive analyses, it is concluded that the directions for dealing with efficiency and functionality issues could be the optimization of transcription factors, the upgradation for delivery systems, the regulation of epigenetic factors and pathways, and the improvement of cellular maintenance conditions. Besides, converting cells into the progenitor state firstly and then differentiating them into the desired cell types with chemical compounds may provide an approach to obtaining functional and safe converted cells in batches with a better proliferative ability. With the emergence of more and more direct reprogramming techniques and approaches with both safety and effectiveness, it is bound to bring a new dawn for mechanism research and therapeutic applications for relevant diseases in the future.


Assuntos
Reprogramação Celular , Células-Tronco Pluripotentes Induzidas , Células Endoteliais , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Miócitos Cardíacos/metabolismo , Fatores de Transcrição/metabolismo
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