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1.
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
2.
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
3.
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
4.
J Dent ; 143: 104882, 2024 Apr.
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
5.
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
6.
Int J Mol Sci ; 25(2)2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38255931

RESUMO

We studied whether the function of presynaptic inhibitory cannabinoid CB1 receptors on the sympathetic nerve fibres innervating resistance vessels is increased in spontaneously hypertensive rats (SHR) like in deoxycorticosterone (DOCA)-salt hypertension. An increase in diastolic blood pressure (DBP) was induced by electrical stimulation of the preganglionic sympathetic neurons or by phenylephrine injection in pithed SHR and normotensive Wistar-Kyoto rats (WKY). The electrically (but not the phenylephrine) induced increase in DBP was inhibited by the cannabinoid receptor agonist CP55940, similarly in both groups, and by the endocannabinoid reuptake inhibitor AM404 in SHR only. The effect of CP55940 was abolished/reduced by the CB1 receptor antagonist AM251 (in both groups) and in WKY by endocannabinoid degradation blockade, i.e., the monoacylglycerol lipase (MAGL) inhibitor MJN110 and the dual fatty acid amide hydrolase (FAAH)/MAGL inhibitor JZL195 but not the FAAH inhibitor URB597. MJN110 and JZL195 tended to enhance the effect of CP55940 in SHR. In conclusion, the function of presynaptic inhibitory CB1 receptors depends on the hypertension model. Although no differences occurred between SHR and WKY under basal experimental conditions, the CB1 receptor function was better preserved in SHR when the endocannabinoid tone was increased by the inhibition of MAGL or the endocannabinoid transporter.


Assuntos
Canabinoides , Carbamatos , Cicloexanóis , Hipertensão , Piperazinas , Succinimidas , Ratos , Animais , Ratos Endogâmicos WKY , Endocanabinoides/farmacologia , Ratos Endogâmicos SHR , Fenilefrina
7.
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
8.
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
9.
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
10.
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
11.
BMC Med Educ ; 24(1): 69, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38233919

RESUMO

OBJECTIVE: The role of the Hospital Pharmacy Preceptor (HPP) is pivotal in upholding the excellence of experiential training and fostering the professional growth of pharmacy interns. However, there is a lack of studies that provide an overview of pharmacy internships from the perspective of HPP. This study explores the experience and expectations of HPPs regarding existing problems and possible coping strategies in intern teaching. METHODS: This is a qualitative study that was conducted through individual interviews and focus group discussions. HPPs were invited as participants from large-scale tertiary hospitals in representative provinces of mainland China. Interview and focus group discussion data were analyzed using thematic analysis to see emerging themes from the data. Nvivo 12 was utilized for data management and processing. RESULTS: Eight individual interviews and two focus group discussions were conducted, involving 14 HPPs as participants. Upon the examination of the interviews and focus group data, four themes were summarized regarding HPPs' perceptions: 1) current presenting problems; 2) possible coping strategies; 3) something HPPs should do; 4) something interns should do. CONCLUSION: This study found that from the HPPs' perspective, the hospital-based pharmacy internship still has some problems from policy to practice, which need to be addressed by the joint efforts of the state, schools, internship bases, pharmacy preceptors, and students.


Assuntos
Educação em Farmácia , Assistência Farmacêutica , Residências em Farmácia , Estudantes de Farmácia , Succinimidas , Humanos , 60670 , Hospitais Gerais , Preceptoria , Pesquisa Qualitativa
12.
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
13.
ACS Nano ; 18(5): 4579-4589, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38258755

RESUMO

To achieve a highly realistic robot, closely mimicking human skin in terms of materials and functionality is essential. This paper presents an all-protein silk fibroin bionic skin (SFBS) that emulates both fast-adapting (FA) and slow-adapting (SA) receptors. The mechanically different silk film and hydrogel, which exhibited skin-like properties, such as stretchability (>140%), elasticity, low modulus (<10 kPa), biocompatibility, and degradability, were prepared through mesoscopic reconstruction engineering to mimic the epidermis and dermis. Our SFBS, incorporating SA and FA sensors, demonstrated a highly sensitive (1.083 kPa-1) static pressure sensing performance (in vitro and in vivo), showed the ability to sense high-frequency vibrations (50-400 Hz), could discriminate materials and sliding, and could even identify the fine morphological differences between objects. As proof of concept, an SFBS-integrated rehabilitation glove was synthesized, which could help stroke patients regain sensory feedback. In conclusion, this work provides a practical approach for developing skin equivalents, prostheses, and smart robots.


Assuntos
Biônica , Fibroínas , Succinimidas , Humanos , Seda , Pele
14.
Biomater Adv ; 158: 213768, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38237320

RESUMO

Despite the clinical prevalence of various bone defect repair materials, a full understanding of their influence on bone repair and regeneration remains elusive. This study focuses on poly(acrylamide) (PAAm) hydrogels, popular 2D model substrates, which have regulable mechanical properties within physiological. However, their bio-inert nature requires surface biofunctionalization to enhance cell-material interactions and facilitate the study of bone repair mechanisms. We utilized PAAm hydrogels of varying stiffness (18, 76 and 295 kPa), employed sulfosuccinimidyl-6-(4'-azido-2'-nitropheny-lamino) hexanoate (sulfo-SANPAH) and N-(3-dimethylaminopropyl)-N-ethylcarbodiimide hydrochloride/N-hydroxysuccinimidyl acrylate (EDC/NHS) as crosslinkers, and cultured macrophages, endothelial cells, and bone mesenchymal stem cells on these hydrogels. Our findings indicated that sulfo-SANPAH's crosslinking efficiency surpassed that of EDC/NHS, irrespective of pore size and stiffness. Importantly, we observed that the stiffness and surface biofunctionalization method of hydrogels significantly impacted cell adhesion and proliferation. The collagen-modified hydrogels by EDC/NHS strategy failed to support the normal biological behavior of bone mesenchymal stem cells and hindered endothelial cell spreading. In contrast, these modified hydrogels by the sulfo-SANPAH method showed good cytocompatibility with the three types of cells. This study underscores the critical role of appropriate conjugation strategies for PAAm hydrogels, providing valuable insights for hydrogel surface modification in bone repair and regeneration research.


Assuntos
Resinas Acrílicas , Azidas , Regeneração Óssea , Células Endoteliais , Succinimidas , Hidrogéis/farmacologia
15.
Nanoscale ; 16(7): 3243-3268, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38265094

RESUMO

A key role in lessening humanity's continuous fight against cancer could be played by photodynamic therapy (PDT), a minimally invasive treatment employed in the medical care of a range of benign disorders and malignancies. Cancerous tissue can be effectively removed by using a light source-excited photosensitizer. Singlet oxygen and reactive oxygen species are produced via the photosensitizer as a result of this excitation. In the recent past, researchers have put in tremendous efforts towards developing photosensitizer molecules for photodynamic treatment (PDT) to treat cancer. Conjugated polymers, characterized by their efficient fluorescence, exceptional photostability, and strong light absorption, are currently under scrutiny for their potential applications in cancer detection and treatment through photodynamic and photothermal therapy. Researchers are exploring the versatility of these polymers, utilizing sophisticated chemical synthesis and adaptable polymer structures to create new variants with enhanced capabilities for generating singlet oxygen in photodynamic treatment (PDT). The incorporation of photosensitizers into conjugated polymer nanoparticles has proved to be beneficial, as it improves singlet oxygen formation through effective energy transfer. The evolution of nanotechnology has emerged as an alternative avenue for enhancing the performance of current photosensitizers and overcoming significant challenges in cancer PDT. Various materials, including biocompatible metals, polymers, carbon, silicon, and semiconductor-based nanomaterials, have undergone thorough investigation as potential photosensitizers for cancer PDT. This paper outlines the recent advances in singlet oxygen generation by investigators using an array of materials, including graphene quantum dots (GQDs), gold nanoparticles (Au NPs), silver nanoparticles (Ag NPs), titanium dioxide (TiO2), ytterbium (Yb) and thulium (Tm) co-doped upconversion nanoparticle cores (Yb/Tm-co-doped UCNP cores), bismuth oxychloride nanoplates and nanosheets (BiOCl nanoplates and nanosheets), and others. It also stresses the synthesis and application of systems such as amphiphilic block copolymer functionalized with folic acid (FA), polyethylene glycol (PEG), poly(ß-benzyl-L-aspartate) (PBLA10) (FA-PEG-PBLA10) functionalized with folic acid, tetra(4-hydroxyphenyl)porphyrin (THPP-(PNIPAM-b-PMAGA)4), pyrazoline-fused axial silicon phthalocyanine (HY-SiPc), phthalocyanines (HY-ZnPcp, HY-ZnPcnp, and HY-SiPc), silver nanoparticles coated with polyaniline (Ag@PANI), doxorubicin (DOX) and infrared (IR)-responsive poly(2-ethyl-2-oxazoline) (PEtOx) (DOX/PEtOx-IR NPs), particularly in NIR imaging-guided photodynamic therapy (fluorescent and photoacoustic). The study puts forward a comprehensive summary and a convincing justification for the usage of the above-mentioned materials in cancer PDT.


Assuntos
Nanopartículas Metálicas , Nanopartículas , Neoplasias , Ácidos Nicotínicos , Fotoquimioterapia , Succinimidas , Humanos , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Fármacos Fotossensibilizantes/química , Oxigênio Singlete/química , Polímeros/química , Ouro/química , Prata , Neoplasias/tratamento farmacológico , Nanopartículas/uso terapêutico , Nanopartículas/química , Doxorrubicina/uso terapêutico , Ácido Fólico
16.
Food Chem ; 443: 138495, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38277937

RESUMO

Applications of pea protein in the food industry have been greatly restricted by its poor functional properties. In order to solve this problem, a novel technique combining enzymatic hydrolysis and fatty acid acylation has been applied in this work to construct a pea protein-fatty acid covalent complex that aims to improve its functional properties. The processed pea protein with increased water solubility tends to decrease the chance of self-aggregation. Additionally, emulsifying and antioxidant properties have also been found after this process. On top of that, the modified pea protein has been characterized by Fourier transform infrared and circular dichroism spectroscopy. These results demonstrate that these properties were mainly caused by the acylation of the amino group from hydrolyzed pea protein and the carboxyl group from the fatty acid. The enzymatic hydrolysis/fatty acid acylation research provides insights into manufacturing high-quality functional lipoproteins from inexpensive pea protein for the food industry.


Assuntos
Proteínas de Ervilha , Succinimidas , Proteínas de Ervilha/química , Hidrolisados de Proteína/química , Ácidos Graxos/química , Acilação
17.
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
18.
Curr Pharm Teach Learn ; 16(3): 174-177, 2024 Mar.
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
19.
Drug Des Devel Ther ; 18: 29-41, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38225973

RESUMO

Background: The preclinical diagnosis of tumors is of great significance to cancer treatment. Near-infrared fluorescence imaging technology is promising for the in-situ detection of tumors with high sensitivity. Methods: Here, a fluorescent probe was synthesized on the basis of Au nanoclusters with near-infrared light emission and applied to fluorescent cancer cell labeling. Near-infrared methionine-N-Hydroxy succinimide Au nanoclusters (Met-NHs-AuNCs) were prepared successfully by one-pot synthesis using Au nanoclusters, methionine, and N-Hydroxy succinimide as frameworks, reductants, and stabilizers, respectively. The specific fluorescence imaging of tumor cells or tissues by fluorescent probe was studied on the basis of SYBYL Surflex-DOCK simulation model of LAT1 active site of overexpressed receptor on cancer cell surface. The results showed that Met-NHs-AuNCs interacted with the surface of LAT1, and C_Score scored the conformation of the probe and LAT1 as five. Results: Characterization and in vitro experiments were conducted to explore the Met-NHs-AuNCs targeted uptake of cancer cells. The prepared near-infrared fluorescent probe (Met-NHs-AuNCs) can specifically recognize the overexpression of L-type amino acid transporter 1 (LAT1) in cancer cells so that it can show red fluorescence in cancer cells. Meanwhile, normal cells (H9c2) have no fluorescence. Conclusion: The fluorescent probe demonstrates the power of targeting and imaging cancer cells.


Assuntos
Nanopartículas Metálicas , Neoplasias , Humanos , Corantes Fluorescentes , Neoplasias/metabolismo , Imagem Óptica/métodos , Metionina/química , Racemetionina , Succinimidas , Ouro/química
20.
Environ Toxicol ; 39(3): 1737-1746, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38050961

RESUMO

Breast cancer (BRCA) is the most common malignancies worldwide with increasing rate. Dolichol phosphate mannose synthase (DPMS) is a critical mannosyltransferase involved in the posttranslational modification of proteins. At present, there is limited knowledge regarding the function of DPMS in breast cancer. In this study, silica analysis in multiple datasets found that dolichyl-phosphate mannosyltransferase subunit 2 (DPM2) is an unfavorable prognostic marker, suggesting its oncogenic role. Cell counting kit-8 and apoptosis assays show that DPM2-silenced cancer cells exhibit decreased growth potential and enhanced cell death rate. Further, transwell and wound healing assays show reduced invasion and migration capabilities in DPM2 knockdown groups, xenograft nude mice model demonstrated smaller tumor volume in DPM2 silenced BC cells. Then, the underlying downstream mechanism of DPM2 in BC was predicted and analyzed, highlighting classical tumorigenic pathways like JAK/STAT signaling pathway and oxidative phosphorylation activated in the cancer group. Finally, ChIP-seq analysis, expression correlation analysis, inhibitor treatment, and dual luciferase assays show that DPM2 is transcriptionally activated by estrogen receptor1 (ESR1). The results show that high expression of DPM2 mRNA is significantly correlated with shorter overall survival (OS) and disease-free survival (DFS) in breast cancer patients, and in vitro knockdown of DPM2 can significantly inhibit the malignant phenotypes of cells, including proliferation, invasion, migration, and apoptosis. These results suggest that DPM2 may play an important role in breast cancer. Altogether, we first uncovered the tumorigenic and prognostic role of DPM2 in breast cancer, cellular assays, and bioinformatics analysis highlighted DPM2 as oncogene via inhibited cancer-related signaling pathways in breast cancer. Besides, DPM2 is transcriptionally activated by ESR1, the signaling axis of ESR1/DPM2 provides a new strategy for BC-targeted therapy.


Assuntos
Neoplasias da Mama , MicroRNAs , Succinimidas , Camundongos , Animais , Humanos , Feminino , Neoplasias da Mama/metabolismo , Manosiltransferases/genética , Manosiltransferases/metabolismo , Camundongos Nus , Prognóstico , Estrogênios/metabolismo , Oncogenes , Proliferação de Células , Linhagem Celular Tumoral , Movimento Celular/genética , MicroRNAs/genética , Regulação Neoplásica da Expressão Gênica
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