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1.
Int J Mol Sci ; 25(13)2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-39000025

RESUMO

3,4-disubstituted maleimides find wide applications in various pharmacologically active compounds. This study presents a highly effective approach for synthesizing derivatives of 3,4-disubstituted maleimides through the direct isomerization of α-succinimide-substituted allenoates, followed by a cascade γ'-addition and aryl imines using PR3 as a catalyst. The resulting series of 3,4-disubstituted maleimides exhibited excellent stereoselectivities, achieving yields of up to 86%. To our knowledge, the phosphine-mediated γ'-addition reaction of allenoates is seldom reported.


Assuntos
Iminas , Maleimidas , Fosfinas , Succinimidas , Maleimidas/química , Maleimidas/síntese química , Fosfinas/química , Catálise , Iminas/química , Succinimidas/química , Estereoisomerismo , Estrutura Molecular , Isomerismo
2.
Biosens Bioelectron ; 261: 116486, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-38861811

RESUMO

Current uric acid detection methodologies lack the requisite sensitivity and selectivity for point-of-care applications. Plasmonic sensors, while promising, demand refinement for improved performance. This work introduces a biofunctionalized sensor predicated on surface plasmon resonance to quantify uric acid within physiologically relevant concentration ranges. The sensor employs the covalent immobilization of uricase enzyme using 1-Ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC) and N-Hydroxysuccinimide (NHS) crosslinking agents, ensuring the durable adherence of the enzyme onto the sensor probe. Characterization through atomic force microscopy and Fourier transform infrared spectroscopy validate surface alterations. The Langmuir adsorption isotherm model elucidates binding kinetics, revealing a sensor binding affinity of 298.83 (mg/dL)-1, and a maximum adsorption capacity of approximately 1.0751°. The biofunctionalized sensor exhibits a sensitivity of 0.0755°/(mg/dL), a linear correlation coefficient of 0.8313, and a limit of detection of 0.095 mg/dL. Selectivity tests against potentially competing interferents like glucose, ascorbic acid, urea, D-cystine, and creatinine showcase a significant resonance angle shift of 1.1135° for uric acid compared to 0.1853° for interferents at the same concentration. Significantly, at a low uric acid concentration of 0.5 mg/dL, a distinct shift of 0.3706° was observed, setting it apart from the lower values noticed at higher concentrations for all typical interferent samples. The uricase enzyme significantly enhances plasmonic sensors for uric acid detection, showcasing a seamless integration of optical principles and biological recognition elements. These sensors hold promise as vital tools in clinical and point-of-care settings, offering transformative potential in biosensing technologies and the potential to revolutionize healthcare outcomes in biomedicine.


Assuntos
Técnicas Biossensoriais , Enzimas Imobilizadas , Ouro , Ressonância de Plasmônio de Superfície , Urato Oxidase , Ácido Úrico , Urato Oxidase/química , Ácido Úrico/química , Ácido Úrico/análise , Ouro/química , Humanos , Enzimas Imobilizadas/química , Técnicas Biossensoriais/métodos , Limite de Detecção , Nanopartículas Metálicas/química , Succinimidas
3.
J Neurosci Res ; 102(5): e25338, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38706427

RESUMO

The enzyme indoleamine 2,3 dioxygenase 1 (IDO1) catalyzes the rate-limiting step in the kynurenine pathway (KP) which produces both neuroprotective and neurotoxic metabolites. Neuroinflammatory signals produced as a result of pathological conditions can increase production of IDO1 and boost its enzymatic capacity. IDO1 and the KP have been implicated in behavioral recovery after human traumatic brain injury (TBI), but their roles in experimental models of TBI are for the most part unknown. We hypothesized there is an increase in KP activity in the fluid percussion injury (FPI) model of TBI, and that administration of an IDO1 inhibitor will improve neurological recovery. In this study, adult male Sprague Dawley rats were subjected to FPI or sham injury and received twice-daily oral administration of the IDO1 inhibitor PF-06840003 (100 mg/kg) or vehicle control. FPI resulted in a significant increase in KP activity, as demonstrated by an increased ratio of kynurenine: tryptophan, in the perilesional neocortex and ipsilateral hippocampus 3 days postinjury (DPI), which normalized by 7 DPI. The increase in KP activity was prevented by PF-06840003. IDO1 inhibition also improved memory performance as assessed in the Barnes maze and anxiety behaviors as assessed in open field testing in the first 28 DPI. These results suggest increased KP activity after FPI may mediate neurological dysfunction, and IDO1 inhibition should be further investigated as a potential therapeutic target to improve recovery.


Assuntos
Lesões Encefálicas Traumáticas , Indolamina-Pirrol 2,3,-Dioxigenase , Masculino , Animais , Ratos Sprague-Dawley , Indolamina-Pirrol 2,3,-Dioxigenase/antagonistas & inibidores , Indolamina-Pirrol 2,3,-Dioxigenase/metabolismo , Lesões Encefálicas Traumáticas/tratamento farmacológico , Lesões Encefálicas Traumáticas/enzimologia , Cinurenina/metabolismo , Modelos Animais de Doenças , Indóis/administração & dosagem , Succinimidas/administração & dosagem , Administração Oral
4.
Anal Chem ; 96(21): 8518-8527, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38711366

RESUMO

Accurate structural determination of proteins is critical to understanding their biological functions and the impact of structural disruption on disease progression. Gas-phase cross-linking mass spectrometry (XL-MS) via ion/ion reactions between multiply charged protein cations and singly charged cross-linker anions has previously been developed to obtain low-resolution structural information on proteins. This method significantly shortens experimental time relative to conventional solution-phase XL-MS but has several technical limitations: (1) the singly deprotonated N-hydroxysulfosuccinimide (sulfo-NHS)-based cross-linker anions are restricted to attachment at neutral amine groups of basic amino acid residues and (2) analyzing terminal cross-linked fragment ions is insufficient to unambiguously localize sites of linker attachment. Herein, we demonstrate enhanced structural information for alcohol-denatured A-state ubiquitin obtained from an alternative gas-phase XL-MS approach. Briefly, singly sodiated ethylene glycol bis(sulfosuccinimidyl succinate) (sulfo-EGS) cross-linker anions enable covalent cross-linking at both ammonium and amine groups. Additionally, covalently modified internal fragment ions, along with terminal b-/y-type counterparts, improve the determination of linker attachment sites. Molecular dynamics simulations validate experimentally obtained gas-phase conformations of denatured ubiquitin. This method has identified four cross-linking sites across 8+ ubiquitin, including two new sites in the N-terminal region of the protein that were originally inaccessible in prior gas-phase XL approaches. The two N-terminal cross-linking sites suggest that the N-terminal half of ubiquitin is more compact in gas-phase conformations. By comparison, the two C-terminal linker sites indicate the signature transformation of this region of the protein from a native to a denatured conformation. Overall, the results suggest that the solution-phase secondary structures of the A-state ubiquitin are conserved in the gas phase. This method also provides sufficient sensitivity to differentiate between two gas-phase conformers of the same charge state with subtle structural variations.


Assuntos
Reagentes de Ligações Cruzadas , Ubiquitina , Ubiquitina/química , Reagentes de Ligações Cruzadas/química , Sódio/química , Gases/química , Cátions/química , Succinimidas/química , Espectrometria de Massas , Íons/química
5.
Methods Cell Biol ; 186: 1-24, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38705595

RESUMO

Broadly speaking, cell tracking dyes are fluorescent compounds that bind stably to components on or within the cells so the fate of the labeled cells can be followed. Their staining should be bright and homogeneous without affecting cell function. For purposes of monitoring cell proliferation, each time a cell divides the intensity of cell tracking dye should diminish equally between daughter cells. These dyes can be grouped into two different classes. Protein reactive dyes label cells by reacting covalently but non-selectively with intracellular proteins. Carboxyfluorescein diacetate succinimidyl ester (CFSE) is the prototypic general protein label. Membrane intercalating dyes label cells by partitioning non-selectively and non-covalently within the plasma membrane. The PKH membrane dyes are examples of lipophilic compounds whose chemistry allows for their retention within biological membranes without affecting cellular growth, viability, or proliferation when used properly. Here we provide considerations based for labeling cell lines and peripheral blood mononuclear cells using both classes of dyes. Examples from optimization experiments are presented along with critical aspects of the staining procedures to help mitigate common risks. Of note, we present data where a logarithmically growing cell line is labeled with both a protein dye and a membrane tracking dye to compare dye loss rates over 6days. We found that dual stained cells paralleled dye loss of the corresponding single stained cells. The decrease in fluorescence intensity by protein reactive dyes, however, was more rapid than that with the membrane reactive dyes, indicating the presence of additional division-independent dye loss.


Assuntos
Proliferação de Células , Fluoresceínas , Corantes Fluorescentes , Coloração e Rotulagem , Succinimidas , Humanos , Corantes Fluorescentes/química , Fluoresceínas/química , Succinimidas/química , Coloração e Rotulagem/métodos , Rastreamento de Células/métodos , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/metabolismo , Animais , Membrana Celular/metabolismo , Membrana Celular/química
6.
Int J Biol Macromol ; 267(Pt 2): 131543, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38614169

RESUMO

A temperature/pH dual sensitive hydrogel with a semi-interpenetrating network (semi-IPN) structure was synthesized through an aqueous amino-succinimide reaction between water-soluble polysuccinimide and polyethyleneimine in the presence of thermosensitive cellulose derivatives. Single-factor experiments were carried out to optimize the preparation conditions of the semi-IPN hydrogel. The swelling behavior and cytotoxicity assay of the hydrogel were tested. Finally, taking 5- fluorouracil (5-Fu) as a model drug, the release performance of the 5-Fu-loaded hydrogel was investigated. The results indicated that the swelling ratio (SR) first decreased and then increased when the pH of the solutions ascended from 2 to 10. The SR decreased with the increase in temperature. In addition, the swelling behavior of the hydrogel was reversible and reproducible under different pH values and temperatures. The prepared hydrogels had good cytocompatibility. The release behavior of 5-Fu was most consistent with the Korsmeyer-Peppas model and followed the case II diffusion. The acidic environment was beneficial for the release of 5-Fu. The preparation process of the semi-IPN hydrogel is simple and the reaction can proceed quickly in water. The strategy introduced here has great potential for application in the preparation of drug carriers.


Assuntos
Celulose , Fluoruracila , Hidrogéis , Succinimidas , Temperatura , Hidrogéis/química , Hidrogéis/síntese química , Celulose/química , Celulose/análogos & derivados , Concentração de Íons de Hidrogênio , Fluoruracila/química , Fluoruracila/farmacologia , Succinimidas/química , Água/química , Liberação Controlada de Fármacos , Portadores de Fármacos/química , Humanos
7.
Neurourol Urodyn ; 43(5): 1207-1216, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38533637

RESUMO

AIMS: Activation of the endocannabinoid system by monoacylglycerol lipase (MAGL) blockade may affect the lower urinary tract function. We investigated the effect of an MAGL inhibitor, MJN110, on neurogenic lower urinary tract dysfunction (LUTD) in the mouse model of spinal cord injury (SCI). METHODS: Female C57BL/6 mice that underwent spinal cord transection at T8-10 level were divided into three groups consisting of (1) vehicle-treated SCI mice, (2) 5 mg/kg, or (3) 10 mg/kg of MJN110-treated SCI mice. MJN110 and vehicle were administered intraperitoneally for 7 days from 4 weeks after spinal cord transection. We then conducted awake cystometrograms and compared urodynamic parameters between three groups. The expression of cannabinoid (CB) receptors, TRP receptors, and inflammatory cytokines in L6-S1 dorsal root ganglia (DRG) or the bladder mucosa were evaluated and compared among three groups. Changes in the level of serum 2-arachidonoylglycerol (2-AG) and bladder MAGL were also evaluated. RESULTS: In the cystometrogram, detrusor overactivity (DO) parameters, such as the number of nonvoiding contraction (NVC), a ratio of time to the 1st NVC to intercontraction interval (ICI), and NVC integrals were improved by MJN110 treatment, and some effects were dose dependent. Although MJN110 did not improve voiding efficiency, it decreased bladder capacity, ICI, and residual urine volume compared to vehicle injection. MJN110 treatment groups had lower CB2, TRPV1, TRPA1, and inflammatory cytokines mRNA levels in DRG and bladder mucosa. Serum 2-AG was increased, and bladder MAGL was decreased after MAGL inhibitor treatment. CONCLUSIONS: MAGL inhibition improved LUTD including attenuation of DO after SCI. Thus, MAGL can be a therapeutic target for neurogenic LUTD after SCI.


Assuntos
Camundongos Endogâmicos C57BL , Monoacilglicerol Lipases , Traumatismos da Medula Espinal , Bexiga Urinária , Urodinâmica , Animais , Monoacilglicerol Lipases/antagonistas & inibidores , Monoacilglicerol Lipases/metabolismo , Traumatismos da Medula Espinal/fisiopatologia , Traumatismos da Medula Espinal/tratamento farmacológico , Traumatismos da Medula Espinal/complicações , Traumatismos da Medula Espinal/metabolismo , Feminino , Bexiga Urinária/efeitos dos fármacos , Bexiga Urinária/fisiopatologia , Urodinâmica/efeitos dos fármacos , Camundongos , Modelos Animais de Doenças , Gânglios Espinais/efeitos dos fármacos , Gânglios Espinais/metabolismo , Gânglios Espinais/fisiopatologia , Receptores de Canabinoides/metabolismo , Receptores de Canabinoides/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Endocanabinoides/metabolismo , Citocinas/metabolismo , Bexiga Urinaria Neurogênica/tratamento farmacológico , Bexiga Urinaria Neurogênica/fisiopatologia , Bexiga Urinaria Neurogênica/etiologia , Sintomas do Trato Urinário Inferior/tratamento farmacológico , Sintomas do Trato Urinário Inferior/fisiopatologia , Sintomas do Trato Urinário Inferior/etiologia , Carbamatos , Succinimidas
8.
Clin Oral Investig ; 28(4): 211, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38480601

RESUMO

OBJECTIVES: The objective of this single-use, five-treatment, five-period, cross-over randomized controlled trial (RCT) was to compare the efficacy in dental plaque removal of a new Y-shaped automatic electric toothbrush (Y-brush) compared to a U-shaped automatic electric toothbrush (U-brush), a manual toothbrushing procedure (for 45 and 120 s), and no brushing (negative control). MATERIALS AND METHODS: Eligible participants were volunteer students randomized to the treatments in the five periods of the study. The primary outcome measure was the reduction in full-mouth plaque score (FMPS) after brushing while the secondary outcome variable was a visual analogic scale (VAS) on subjective clean mouth sensation. Mixed models were performed for difference in FMPS and VAS. RESULTS: After brushing procedures, manual toothbrushing (120 s) showed a statistically significant reduction in FMPS than Y-brush (difference 36.9; 95%CI 29.6 to 44.1, p < 0.0001), U-brush (difference 42.3; 95%CI 35.1 to 49.6, p < 0.0001), manual brushing (45 s) (difference 13.8; 95%CI 6.5 to 21.1, p < 0.0001), and No brushing (difference 46.6; 95%CI 39.3 to 53.9, p < 0.0001). Y-brush was significantly more effective than No brushing (difference 9.8; 95%CI 2.5 to 17.0, p = 0.0030), while there was no significant difference compared to U- brush. Similar results were obtained for the differences in the Clean Mouth VAS. CONCLUSIONS: Y-brush was significantly more effective than no brushing (negative control) in removing dental plaque. When compared to manual toothbrushing for both 45 and 120 s, however, Y-brush was less effective in dental plaque removal. CLINICAL RELEVANCE: Modified design of automatic toothbrushing devices could improve plaque reduction, especially in patients with intellectual disabilities or motor difficulties.


Assuntos
Placa Dentária , Succinimidas , Escovação Dentária , Humanos , Nylons , Placa Dentária/terapia , Desenho de Equipamento , Índice de Placa Dentária , Método Simples-Cego , Estudos Cross-Over
9.
Am J Biol Anthropol ; 184(1): e24916, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38441408

RESUMO

OBJECTIVES: Studies on oral processing are often snapshots of behaviors that examine feeding through individual bouts. In this study, we expand on our previous work comparing bite/chew variables per feeding bout to summed daily biting, chewing, and food intake to interpret loading that could have potential morphological effects. MATERIALS AND METHODS: We observed sympatric Lemur catta and Propithecus verreauxi over two field seasons in the dry forest of Bezà Mahafaly Special Reserve in southwestern Madagascar. Bite and chew rates determined from videos filmed during observations were multiplied with time spent feeding on specific foods during focal follows to calculate daily values for each feeding bout. Food mechanical properties (FMPs) were tested on dietary items with a portable tester. We contrasted daily bite/chew numbers and intake with FMPs, species, season, and food shape. RESULTS: Daily bite and chew numbers increased with maximum, but not average, food toughness. Daily intake decreased with average and maximum toughness. Season had a strong effect on daily bites and chews, but not on intake. Food shape influenced intake and total bite and chew numbers. The lemur species did not differ in our models. DISCUSSION: Maximum food toughness impacted feeding behaviors and intake, which is consistent with higher loads having a greater effect on morphology. In contrast to feeding per bout, cumulative biting and chewing did not differ between species; taking feeding frequency into consideration affects interpretation of jaw loading. Finally, biting, as much as chewing, may generate strains that impact morphology.


Assuntos
Lemur , Lemuridae , Succinimidas , Animais , Lemur/anatomia & histologia , Dieta , Alimentos
10.
Anticancer Res ; 44(4): 1377-1387, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38537976

RESUMO

BACKGROUND/AIM: Adoptive cell therapy using antigen-specific T cells is a promising treatment modality for cancer patients. Various methods to isolate specific T cells and identify corresponding T cell receptor (TCR) sequences are known. This study aimed to identify antigen-specific TCR from T cells isolated using carboxyfluorescein succinimidyl ester (CFSE), which marks proliferating activated T cells. MATERIALS AND METHODS: CFSE stained healthy donor peripheral blood mononuclear cells (PBMCs) were treated with cytomegalovirus (CMV) or Epstein-Barr virus (EBV) peptides for seven days. Then, proliferating T cells with decreased CFSE staining were isolated and single cell VDJ sequencing was performed on isolated T cells to identify antigen-specific TCRs. RESULTS: As antigen-specific TCR candidates, ten TCR clones were selected for the CMV antigen and five for the EBV antigen. The reactivity of ten CMV TCR-transduced T cells and one EBV TCR-transduced T cell toward T2 cells pulsed with CMV or EBV peptide was confirmed via NFAT-luciferase, IFN-γ ELISA, and cytotoxicity assays. CONCLUSION: Identification of antigen-specific TCRs with CFSE staining is a valid method for the development of effective immunotherapy. The identified CMV- or EBV-specific TCRs can be used for adoptive cell therapy to treat cancer.


Assuntos
Infecções por Citomegalovirus , Infecções por Vírus Epstein-Barr , Fluoresceínas , Neoplasias , Succinimidas , Humanos , Linfócitos T , Infecções por Vírus Epstein-Barr/terapia , Herpesvirus Humano 4 , Leucócitos Mononucleares , Citomegalovirus , Receptores de Antígenos de Linfócitos T
11.
J Dent ; 143: 104882, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38331378

RESUMO

OBJECTIVES: This study investigated the relationship between bacterial growth, viability, and extracellular polymeric substances (EPS) formation in biofilms, particularly regarding resistance development. It also examined the impact of chemical factors on the EPS matrix and bacterial proliferation in oral biofilms. METHODS: Three multi-species oral biofilms were incubated in anaerobic conditions. Three strains of Enterococcus faecalis were incubated in aerobic conditions. The incubation periods ranged from 0 h to 7 days for short-term biofilms, and from 3 to 90 days for long-term biofilms. Fluorescent labeling with carboxyfluorescein diacetate succinimidyl ester (CFSE) and flow cytometry were used to track EPS and bacterial growth. Confocal laser scanning microscopy (CLSM) assessed bacterial viability and EPS structure. Biofilms aged 7, 14, and 21 days were treated with 2 % chlorhexidine (CHX) and 1 % sodium hypochlorite (NaOCl) to evaluate their effects on EPS and bacterial proliferation. RESULTS: Short-term biofilms showed rapid bacterial proliferation and a gradual increase in EPS, maintaining stable viability. In the first two weeks, a significant rise in CFSE indicated growing maturity. From 14 to 90 days, EPS and CFSE levels stabilized. Following treatment, CHX significantly reduced bacterial proliferation, while NaOCl decreased EPS volume. CONCLUSIONS: Biofilm development involves a balance between bacterial proliferation and EPS production. The complexity of this process poses challenges in treating biofilm-associated infections, requiring strategies tailored to the biofilm's developmental stage. CLINICAL SIGNIFICANCE: For effective root canal treatment, it is imperative to focus on reducing bacterial proliferation during the early stages of oral infections. In contrast, strategies aimed at minimizing EPS production could be more beneficial for long-term management of these conditions.


Assuntos
Biofilmes , Matriz Extracelular de Substâncias Poliméricas , Fluoresceínas , Succinimidas , Clorexidina/farmacologia , Hipoclorito de Sódio/farmacologia , Enterococcus faecalis , Microscopia Confocal , Proliferação de Células , Irrigantes do Canal Radicular/farmacologia
12.
Pest Manag Sci ; 80(7): 3278-3292, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38372427

RESUMO

BACKGROUND: Faced with the need to develop new herbicides with modes of action different to those observed for existing agrochemicals, one of the most promising strategies employed by synthetic chemists involves the structural modification of molecules found in natural products. Molecules containing amides, imides, and epoxides as functional groups are prevalent in nature and find extensive application in synthesizing more intricate compounds due to their biological properties. In this context, this paper delineates the synthesis of N-phenylnorbornenesuccinimide derivatives, conducts biological assays, and carries out in silico investigation of the protein target associated with the most potent compound in plant organisms. The phytotoxic effects of the synthesized compounds (2-29) were evaluated on Allium cepa, Bidens pilosa, Cucumis sativus, Sorghum bicolor, and Solanum lycopersicum. RESULTS: Reaction of endo-bicyclo[2.2.1]hept-5-ene-3a,7a-dicarboxylic anhydride (1) with aromatic amines led to the N-phenylnorbornenesuccinic acids (2-11) with yields ranging from 75% to 90%. Cyclization of compounds (2-11) in the presence of acetic anhydride and sodium acetate afforded N-phenylnorbornenesuccinimides (12-20) with yields varying from 65% to 89%. Those imides were then subjected to epoxidation reaction to afford N-phenylepoxynorbornanesuccimides (21-29) with yields from 60% to 90%. All compounds inhibited the growth of seedlings of the plants evaluated. Substance 23 was the most active against the plants tested, inhibiting 100% the growth of all species in all concentrations. Cyclophilin was found to be the enzymatic target of compound 23. CONCLUSION: These findings suggest that derivatives of N-phenylnorbornenesuccinimide are promising compounds in the quest for more selective and stable agrochemicals. This perspective reinforces the significance of these derivatives as potential innovative herbicides and emphasizes the importance of further exploring their biological activity on weeds. © 2024 Society of Chemical Industry.


Assuntos
Herbicidas , Herbicidas/farmacologia , Herbicidas/química , Succinimidas/farmacologia , Succinimidas/química , Solanum lycopersicum/efeitos dos fármacos , Solanum lycopersicum/crescimento & desenvolvimento , Cebolas/efeitos dos fármacos , Sorghum/efeitos dos fármacos , Sorghum/crescimento & desenvolvimento , Cucumis sativus/efeitos dos fármacos , Cucumis sativus/crescimento & desenvolvimento
13.
Int Immunopharmacol ; 129: 111660, 2024 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-38350357

RESUMO

BACKGROUND: Human amniotic mesenchymal stem cells (hAMSCs) derived from amniotic membrane have multilineage differentiation, immunosuppressive, and anti-inflammation which makes them suitable for the treatment of various diseases. OBJECTIVE: This study aimed to explore the therapeutic effect and molecular mechanism of hAMSCs in ventricular remodeling (VR). METHODS: hAMSCs were characterized by a series of experiments such as flow cytometric analysis, immunofluorescence, differentiative induction and tumorigenicity. Mouse VR model was induced by isoproterenol (ISO) peritoneally, and the therapeutic effects and the potential mechanisms of hAMSCs transplantation were evaluated by echocardiography, carboxy fluorescein diacetate succinimidyl ester (CFSE) labeled cell tracing, histochemistry, qRT-PCR and western blot analysis. The co-culturing experiments were carried out for further exploring the mechanisms of hAMSCs-derived conditioned medium (CM) on macrophage polarization and fibroblast fibrosis in vitro. RESULTS: hAMSCs transplantation significantly alleviated ISO-induced VR including cardiac hypertrophy and fibrosis with the improvements of cardiac functions. CFSE labeled hAMSCs kept an undifferentiated state in heart, indicating that hAMSCs-mediated the improvement of ISO-induced VR might be related to their paracrine effects. hAMSCs markedly inhibited ISO-induced inflammation and fibrosis, seen as the increase of M2 macrophage infiltration and the expressions of CD206 and IL-10, and the decreases of CD86, iNOS, COL3 and αSMA expressions in heart, suggesting that hAMSCs transplantation promoted the polarization of M2 macrophages and inhibited the polarization of M1 macrophages. Mechanically, hAMSCs-derived CM significantly increased the expressions of CD206, IL-10, Arg-1 and reduced the expressions of iNOS and IL-6 in RAW264.7 macrophages in vitro. Interestingly, RAW264.7-CM remarkably promoted the expressions of anti-inflammatory factors such as IL-10, IDO, and COX2 in hAMSCs. Furthermore, the CM derived from hAMSCs pretreated with RAW264.7-CM markedly inhibited the expressions of fibrogenesis genes such as αSMA and COL3 in 3T3 cells. CONCLUSION: Our results demonstrated that hAMSCs effectively alleviated ISO-induced cardiac hypertrophy and fibrosis, and improved the cardiac functions in mice, and the underlying mechanisms might be related to inhibiting the inflammation and fibrosis during the ventricular remodeling through promoting the polarization of CD206hiIL-10hi macrophages in heart tissues. Our study strongly suggested that by taking the advantages of the potent immunosuppressive and anti-inflammatory effects, hAMSCs may provide an alternative therapeutic approach for prevention and treatment of VR clinically.


Assuntos
Fluoresceínas , Interleucina-10 , Células-Tronco Mesenquimais , Succinimidas , Camundongos , Humanos , Animais , Interleucina-10/farmacologia , Âmnio , Isoproterenol , Remodelação Ventricular , Macrófagos , Inflamação/induzido quimicamente , Inflamação/terapia , Anti-Inflamatórios/uso terapêutico , Anti-Inflamatórios/farmacologia , Fibrose , Cardiomegalia
14.
Curr Pharm Teach Learn ; 16(3): 174-177, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38218657

RESUMO

INTRODUCTION: The purpose of this study was to describe the effect of converting multiple choice questions (MCQs) that include an "all of the above" (AOTA) answer option to a "select all that apply" (SATA) question type on question performance. METHODS: A summative assessment at the end of the first professional pharmacy year was comprised of approximately 50 multiple choice questions covering material from all courses taught. Eight questions contained AOTA answer options and were converted to SATA items in the subsequent year by eliminating the AOTA option and including the words "select all that apply" in the stem. Majority of the other questions included on the exam remained the same between the two years. Item difficulty, item discrimination, point biserial, and distractor efficiency were used to compare the MCQs on exams in the two years. RESULTS: The AOTA questions were significantly easier and less discriminating than the SATA items. The performance of the remaining questions on the exam did not differ between the years. The distractor efficiency increased significantly when the questions were converted to SATA items. CONCLUSIONS: MCQs with AOTA answer options are discouraged due to poor item construction resulting in poor discrimination between high and low performing students. The AOTA questions are easily converted to the SATA format. The result of this conversion is a more difficult and more discriminating question with all answer options chosen, which prevents students from easily guessing the correct answer.


Assuntos
Avaliação Educacional , Estudantes de Medicina , Succinimidas , Sulfetos , Humanos , Avaliação Educacional/métodos
15.
J Reprod Dev ; 70(2): 55-64, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38246612

RESUMO

The mammalian X chromosome exhibits enrichment in genes associated with germ cell development. Previously, we generated a rat model of Becker muscular dystrophy (BMD) characterized by an in-frame mutation in the dystrophin gene, situated on the X chromosome and responsible for encoding a protein crucial for muscle integrity. Male BMD rats are infertile owing to the absence of normal spermatids in the epididymis. Within the seminiferous tubules of BMD rats, elongated spermatids displayed abnormal morphology. To elucidate the cause of infertility, we identified a putative gene containing an open reading frame situated in the intronic region between exons 6 and 7 of the dystrophin gene, specifically deleted in male BMD rats. This identified gene, along with its encoded protein, exhibited specific detection within the testes, exclusively localized in round to elongated spermatids during spermiogenesis. Consequently, we designated the encoded protein as dystrophin-locus-derived testis-specific protein (DTSP). Given the absence of DTSP in the testes of BMD rats, we hypothesized that the loss of DTSP contributes to the infertility observed in male BMD rats.


Assuntos
Infertilidade , Succinimidas , Testículo , Masculino , Ratos , Animais , Testículo/metabolismo , Distrofina/genética , Distrofina/metabolismo , Espermatogênese/genética , Proteínas/metabolismo , Infertilidade/metabolismo , Mamíferos
16.
Nan Fang Yi Ke Da Xue Xue Bao ; 44(1): 36-44, 2024 Jan 20.
Artigo em Chinês | MEDLINE | ID: mdl-38293974

RESUMO

OBJECTIVE: To explore the correlation between polycystic ovary syndrome (PCOS) and periodontitis in light of cytokines levels, sex hormone levels and metabolism-related indicators and their changes during progression of the two diseases. METHODS: Twenty healthy subjects and 40 patients diagnosed with PCOS underwent full-mouth periodontal examinations to obtain full-mouth plaque score (FMPS), gingival bleeding index of probing (BOP), probing depth (PD), and clinical attachment level (CAL). The participants were divided into Group A without periodontitis or PCOS (n=15), Group B with PCOS but without periodontitis (n=28), Group C with periodontitis but without PCOS (n=5), and Group D with both diseases (n=12). Serum levels of luteinizing hormone/follicle stimulating hormone (LH/FSH), testosterone, prolactin, progesterone and estradiol, and the levels of interleukin 6 (IL-6), IL-17A, tumor necrosis factor α and matrix metalloproteinase 8 (MMP-8) in both serum and saliva samples were measured at the time of enrolment and at 3 and 6 months after enrolment and compared among the 4 groups. RESULTS: Serum MMP-8 level was significantly higher in Group B than in Group A (P<0.05). Salivary MMP-8 level was significantly higher in Group D than in Group B (P<0.05). Salivary MMP-8, LH, and LH/FSH levels and serum and salivary IL-6 and progesterone levels all tended to increase in the 6 months after enrollment (OR>1, P<0.05). During the follow-up period, serum IL-6 levels differed significantly between the non-PCOS groups (A and C) and PCOS groups (B and D)(P<0.05); serum IL-6 and salivary MMP-8 levels differed significantly between the non-periodontitis groups (A and B) and periodontitis groups (C and D)(P<0.05). Spearman correlation analysis indicated positive correlations of LH and LH/FSH with PD (P<0.05); testosterone and LH/FSH were positively correlated with serum MMP-8 levels (P<0.05), and PD, BOP and FMPS were positively correlated with salivary MMP-8 levels (P<0.01). CONCLUSION: There is a correlation between PCOS and periodontitis, and their progression is accompanied by changes in serum and salivary levels of pro-inflammatory cytokines and serum sex hormones.


Assuntos
Periodontite , Síndrome do Ovário Policístico , Succinimidas , Feminino , Humanos , Estudos Prospectivos , Metaloproteinase 8 da Matriz , Progesterona , Interleucina-6 , Hormônio Luteinizante , Hormônio Foliculoestimulante , Testosterona
17.
J Mater Chem B ; 12(5): 1244-1256, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38168715

RESUMO

Implanting physical barrier materials to separate wounds from their surroundings is a promising strategy for preventing postoperative adhesions. Herein, we develop a material that switches from an anti-adhesive surface to an adhesive surface, preventing adhesion in the early stage of transplantation and then promoting recellularization. In this study, 2-arm, 4-arm, and 8-arm poly(ethylene glycol) succinimidyl glutarate (2-, 4-, 8-arm PEG-NHS) were used to modify the surface of decellularized porcine and bovine pericardium. The number of free amines on the surface of each material significantly decreased following modification regardless of the reaction molar ratio of NH2 and NHS, the number of PEG molecule branches, and the animal species of the decellularized tissue. The structure and mechanical properties of the pericardium were maintained after modification with PEG molecules. The time taken for the PEG molecules to detach through hydrolysis of the ester bonds differed between the samples, which resulted in different cell repulsion periods. By adjusting the reaction molar ratio, the number of PEG molecule branches, and the animal species of the decellularized pericardium, the duration of cell repulsion can be controlled and is expected to provide an anti-adhesion material for a variety of surgical procedures.


Assuntos
Polietilenoglicóis , Medicina Estatal , Succinimidas , Suínos , Animais , Bovinos , Polietilenoglicóis/farmacologia , Polietilenoglicóis/química , Adesão Celular , Pericárdio
18.
Spectrochim Acta A Mol Biomol Spectrosc ; 309: 123867, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38198993

RESUMO

Succinimide intermediates play the crucial role in the nucleation process for protein amyloid fibril formation, as they can usually induce a non-native conformation in a fraction of soluble proteins to render amyloidogenicity and neurotoxicity. Thus, in situ detection of succinimide intermediates during amyloid fibrillation kinetics is of considerable importance, albeit challenging, because these succinimides are generally unstable in physiological conditions. Here, we found an in situ Raman spectral fingerprint to trace the succinimide intermediates in amyloid fibril formation, wherein the carbonyl symmetric stretching of cyclic imide in the succinimide derivative is located at ca. 1790 cm-1. Using its intensity as an indicator of succinimide intermediates, we have in situ detected and unravelled the role of succinimide intermediates during the oligomer formation from the Bz-Asp-Gly-NH2 dipeptide or the amyloid fibrillation kinetics of lysozyme with thermal/acid treatment.


Assuntos
Amiloide , Succinimidas , Amiloide/química , Succinimidas/química , Cinética
19.
Sci Total Environ ; 914: 169936, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38199370

RESUMO

Nuclear power plants, recognized for their extended operational life, minimal greenhouse gas emissions, and high-power density, are deemed as reliable energy sources. Nonetheless, concerns persist regarding the radioactive discharges from these plants and their potential impact on health and the environment. To comprehend the radiological implications of such releases, this study presents, for the first time, an analysis of radiological data from 7 Indian nuclear power plants (NPPs), collected by Indian environmental survey laboratories (ESL) over the past two decades (2000-2020). This dataset encompasses radioactivity concentrations in the atmospheric, aquatic, and terrestrial environments within a 30 km radius of each NPP, as well as the annual cumulative external gamma doses recorded by environmental thermoluminescence dosimeters (TLDs). The analysis yielded several key findings: (i) Radioactivity concentrations around the NPPs were low and comparable to values measured at other nuclear power plant sites worldwide; (ii) Tritium concentrations in receiving water bodies were <1 % of the internationally recommended limit of 10,000 Bq/l; (iii) The estimated total radiation doses to the public were at most 10 % of the stipulated regulatory dose limit of 1000 µSv and consistently decreased over the study period and (iv) Variations in doses among the NPP sites were primarily attributed to legacy technology used in specific reactors. These results indicate efficient and secure reactor operations and the minimal contribution of Indian nuclear power plants to anthropogenic doses in the country. The findings hold potential significance for reinforcing India's commitment to advancing its nuclear power program.


Assuntos
Monitoramento de Radiação , Succinimidas , Poluentes Radioativos da Água , Centrais Nucleares , Monitoramento de Radiação/métodos , Trítio , Poluentes Radioativos da Água/análise , Centrais Elétricas
20.
Int J Biol Macromol ; 260(Pt 2): 129451, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38232886

RESUMO

Jacalin, the jackfruit seed lectin, exhibits high specificity for the tumor-specific T-antigen and is used in various biomedical and biotechnological applications. Here, we report biophysical studies on the thermal unfolding of jacalin and the effect of pH and temperature on its secondary structure. Differential scanning calorimetric (DSC) studies revealed that native jacalin unfolds at ∼60 °C and that carbohydrate binding stabilizes the protein structure. Circular dichroism spectroscopic studies indicated that the secondary structure of jacalin remains mostly unaffected over pH 2.0-9.0, whereas considerable changes were observed in the tertiary structure. DSC experiments demonstrated that jacalin exhibits two overlapping transitions between pH 2 and 5, which could be attributed to dissociation of the tetrameric protein into subunits and their unfolding. Interestingly, only one transition between pH 6 and 9 was observed, suggesting that the subunit dissociation and unfolding occur simultaneously. While quenching of the protein intrinsic fluorescence by acrylamide increased significantly upon carbohydrate binding, quenching by succinimide is essentially unaffected. We attribute this difference to increased exposure of Trp-123 in the α-chain as it is involved in carbohydrate binding. Both acrylamide and succinimide gave biphasic Stern-Volmer plots, consistent with differential accessibility of the two tryptophan residues of jacalin to them.


Assuntos
Lectinas , Neoplasias , Lectinas de Plantas , Humanos , Lectinas/química , Temperatura , Triptofano/química , Desnaturação Proteica , Concentração de Íons de Hidrogênio , Succinimidas , Carboidratos , Acrilamidas , Dicroísmo Circular , Espectrometria de Fluorescência , Dobramento de Proteína
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