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1.
JHEP Rep ; 6(7): 101095, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38961852

RESUMO

Background & Aims: Treatment of alcohol use disorder (AUD) improves survival in patients with alcohol-related cirrhosis. However, medications for alcohol use disorder (MAUD) are underutilized in this population, partially due to concerns regarding drug-induced liver injury (DILI). Our aim was to evaluate the safety of naltrexone in patients with cirrhosis. Methods: This was a retrospective study of patients with cirrhosis who were prescribed naltrexone using the VOCAL (Veterans Outcomes and Costs Associated with Liver Disease) database. Patients with new initiation of naltrexone after diagnosis of cirrhosis who had liver enzymes checked within a 3-month time frame were included. A chart review was performed on patients who developed alanine aminotransferase or alkaline phosphatase elevations to more than 2× or 5× the upper limit of normal, respectively. The RUCAM (Roussel Uclaf causality assessment method) was used to determine if DILI occurred. Results: A total of 3,285 patients with cirrhosis were initiated on naltrexone, of whom 2,940 had laboratory testing during the high-risk DILI period. Only 2% of patients had liver enzyme elevations, and among those, 30 (48%) were classified as "DILI excluded" and 32 (52%) were classified as "DILI unlikely". No patients were classified as possible, probable, or highly probable DILI. No deaths or new decompensations were attributed to naltrexone. Conclusions: Naltrexone in patients with cirrhosis was not associated with development of DILI using RUCAM scoring. Naltrexone appears to be safe in patients with compensated and decompensated cirrhosis. Impact and Implications: Naltrexone is an effective medication for treating alcohol use disorder but is underutilized in patients with underlying liver disease due to historical concerns regarding hepatotoxicity. This retrospective study shows no drug-induced liver injury in a large cohort of patients with cirrhosis with new initiation of naltrexone. This study may encourage providers to prescribe naltrexone to patients with existing liver disease with ongoing alcohol use disorder.

2.
JAMA Netw Open ; 7(7): e2420963, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38985470

RESUMO

Importance: The risk of hepatocellular carcinoma (HCC) declines over time after hepatitis C virus (HCV) cure by direct-acting antiviral (DAA) therapies. Liver society guidelines recommend continuing HCC screening for these patients, but data on screening outcomes are lacking. Objective: To evaluate the association of HCC screening after HCV cure with overall survival. Design, Setting, and Participants: This cohort study evaluated patients with HCV cirrhosis who achieved DAA-induced HCV cure in the Veterans Affairs health care system between January 2014 and December 2022. Data analysis occurred from October 2023 to January 2024. Exposures: The percentage of time spent up to date with recommended HCC screening was calculated by year of follow-up and during the 4 years preceding HCC diagnosis (the detectable asymptomatic phase). Main Outcomes and Measures: The primary outcome was overall survival after HCC diagnosis and was compared by percentage of time spent up to date with screening using Kaplan-Meier analyses and Cox proportional hazards regression. Early-stage HCC at diagnosis and curative treatment were secondary outcomes assessed using logistic regression. Results: A total of 16 902 individuals were included (median [IQR] age, 64.0 [60.5-67.4] years; 16 426 male [97.2%]), of whom 1622 developed HCC. The cumulative incidence of HCC declined from 2.4% (409 of 16 902 individuals) to 1.0% (27 of 2833 individuals) from year 1 to year 7 of follow-up. Being up to date with screening for at least 50% of time during the 4 years preceding HCC diagnosis was associated with improved overall survival (log-rank test of equality over strata P = .002). In multivariate analysis, each 10% increase in follow-up spent up to date with screening was associated with a 3.2% decrease in the hazard of death (hazard ratio, 0.97; 95% CI, 0.95-0.99). There was a statistically significant interaction between time since HCV cure and screening, with no association observed among those who received a diagnosis of HCC more than 5 years after HCV cure. Each 10% of time spent up to date with screening was associated with a 10.1% increased likelihood of diagnosis with early-stage HCC (95% CI, 6.3%-14.0%) and a 6.8% increased likelihood of curative treatment (95% CI, 2.8%-11.0%). Conclusions and Relevance: In this cohort study of persons with HCV-related cirrhosis who achieved HCV cure and subsequently developed HCC, remaining up to date with screening was associated with improved overall survival, supporting the screening of eligible individuals.


Assuntos
Antivirais , Carcinoma Hepatocelular , Detecção Precoce de Câncer , Cirrose Hepática , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/epidemiologia , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/epidemiologia , Masculino , Pessoa de Meia-Idade , Feminino , Cirrose Hepática/mortalidade , Cirrose Hepática/complicações , Idoso , Antivirais/uso terapêutico , Detecção Precoce de Câncer/métodos , Hepatite C Crônica/complicações , Hepatite C Crônica/tratamento farmacológico , Estudos de Coortes , Estados Unidos/epidemiologia , Programas de Rastreamento/métodos
3.
Hepatol Commun ; 8(7)2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38967582

RESUMO

BACKGROUND: Fibrosis-4 (FIB4) is a recommended noninvasive test to assess hepatic fibrosis among patients with metabolic dysfunction-associated steatotic liver disease (MASLD). Here, we used FIB4 trajectory over time (ie, "slope" of FIB4) as a surrogate marker of liver fibrosis progression and examined if FIB4 slope is associated with clinical and genetic factors among individuals with clinically defined MASLD within the Million Veteran Program Cohort. METHODS: In this retrospective cohort study, FIB4 slopes were estimated through linear regression for participants with clinically defined MASLD and FIB4 <2.67 at baseline. FIB4 slope was correlated with demographic parameters and clinical outcomes using logistic regression and Cox proportional hazard models. FIB4 slope as a quantitative phenotype was used in a genome-wide association analysis in ancestry-specific analysis and multiancestry meta-analysis using METAL. RESULTS: FIB4 slopes, generated from 98,361 subjects with MASLD (16,045 African, 74,320 European, and 7996 Hispanic), showed significant associations with sex, ancestry, and cardiometabolic risk factors (p < 0.05). FIB4 slopes also correlated strongly with hepatic outcomes and were independently associated with time to cirrhosis. Five genetic loci showed genome-wide significant associations (p < 5 × 10-8) with FIB4 slope among European ancestry subjects, including 2 known (PNPLA3 and TM6SF2) and 3 novel loci (TERT 5.1 × 10-11; LINC01088, 3.9 × 10-8; and MRC1, 2.9 × 10-9). CONCLUSIONS: Linear trajectories of FIB4 correlated significantly with time to progression to cirrhosis, with liver-related outcomes among individuals with MASLD and with known and novel genetic loci. FIB4 slope may be useful as a surrogate measure of fibrosis progression.


Assuntos
Progressão da Doença , Estudo de Associação Genômica Ampla , Cirrose Hepática , Humanos , Masculino , Feminino , Cirrose Hepática/genética , Cirrose Hepática/complicações , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Idoso , Proteínas de Membrana/genética , Fígado Gorduroso/genética , Biomarcadores , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/complicações , Aciltransferases , Fosfolipases A2 Independentes de Cálcio
4.
Biol Res ; 57(1): 40, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38890753

RESUMO

BACKGROUND: The brain cortex is responsible for many higher-level cognitive functions. Disruptions during cortical development have long-lasting consequences on brain function and are associated with the etiology of brain disorders. We previously found that the protein tyrosine phosphatase receptor delta Ptprd, which is genetically associated with several human neurodevelopmental disorders, is essential to cortical brain development. Loss of Ptprd expression induced an aberrant increase of excitatory neurons in embryonic and neonatal mice by hyper-activating the pro-neurogenic receptors TrkB and PDGFRß in neural precursor cells. However, whether these alterations have long-lasting consequences in adulthood remains unknown. RESULTS: Here, we found that in Ptprd+/- or Ptprd-/- mice, the developmental increase of excitatory neurons persists through adulthood, affecting excitatory synaptic function in the medial prefrontal cortex. Likewise, heterozygosity or homozygosity for Ptprd also induced an increase of inhibitory cortical GABAergic neurons and impaired inhibitory synaptic transmission. Lastly, Ptprd+/- or Ptprd-/- mice displayed autistic-like behaviors and no learning and memory impairments or anxiety. CONCLUSIONS: These results indicate that loss of Ptprd has long-lasting effects on cortical neuron number and synaptic function that may aberrantly impact ASD-like behaviors.


Assuntos
Transtorno Autístico , Neurônios , Proteínas Tirosina Fosfatases Classe 2 Semelhantes a Receptores , Animais , Proteínas Tirosina Fosfatases Classe 2 Semelhantes a Receptores/metabolismo , Proteínas Tirosina Fosfatases Classe 2 Semelhantes a Receptores/genética , Camundongos , Transtorno Autístico/genética , Transtorno Autístico/fisiopatologia , Modelos Animais de Doenças , Masculino , Córtex Cerebral/metabolismo , Camundongos Knockout , Transmissão Sináptica/fisiologia , Camundongos Endogâmicos C57BL , Feminino
5.
Adv Healthc Mater ; : e2401562, 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38852041

RESUMO

Protein hydrogels with tailored stimuli-responsive features and tunable stiffness have garnered considerable attention due to the growing demand for biomedical soft robotics. However, integrating multiple responsive features toward intelligent yet biocompatible actuators remains challenging. Here, we report a facile approach that synergistically combines genetic and chemical engineering for the design of protein hydrogel actuators with programable complex spatial deformation. Genetically engineered silk-elastin-like proteins (SELPs) were encoded with stimuli-responsive motifs and enzymatic crosslinking sites via simulation-guided genetic engineering strategies. Chemical modifications of the recombinant proteins were also used as secondary control points to tailor material properties, responsive features, and anisotropy in SELP hydrogels. As a proof-of-concept example, diazonium coupling chemistry was exploited to incorporate sulfanilic acid groups onto the tyrosine residues in the elastin domains of SELPs to achieve patterned SELP hydrogels. These hydrogels can be programmed to perform various actuations, including controllable bending, buckling, and complex deformation under external stimuli, such as temperature, ionic strength, or pH. With the inspiration of genetic and chemical engineering in natural organisms, this work offers a predictable, tunable, and environmentally sustainable approach for the fabrication of programmed intelligent soft actuators, with implications for a variety of biomedical materials and bio-robotics needs. This article is protected by copyright. All rights reserved.

6.
Nat Commun ; 15(1): 4879, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38849354

RESUMO

The mammalian neocortex comprises an enormous diversity regarding cell types, morphology, and connectivity. In this work, we discover a post-transcriptional mechanism of gene expression regulation, protein translation, as a determinant of cortical neuron identity. We find specific upregulation of protein synthesis in the progenitors of later-born neurons and show that translation rates and concomitantly protein half-lives are inherent features of cortical neuron subtypes. In a small molecule screening, we identify Ire1α as a regulator of Satb2 expression and neuronal polarity. In the developing brain, Ire1α regulates global translation rates, coordinates ribosome traffic, and the expression of eIF4A1. Furthermore, we demonstrate that the Satb2 mRNA translation requires eIF4A1 helicase activity towards its 5'-untranslated region. Altogether, we show that cortical neuron diversity is generated by mechanisms operating beyond gene transcription, with Ire1α-safeguarded proteostasis serving as an essential regulator of brain development.


Assuntos
Proteínas de Ligação à Região de Interação com a Matriz , Neocórtex , Neurônios , Biossíntese de Proteínas , Proteínas Serina-Treonina Quinases , Animais , Neocórtex/metabolismo , Neocórtex/citologia , Neocórtex/embriologia , Neurônios/metabolismo , Neurônios/citologia , Camundongos , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Serina-Treonina Quinases/genética , Proteínas de Ligação à Região de Interação com a Matriz/metabolismo , Proteínas de Ligação à Região de Interação com a Matriz/genética , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Regulação da Expressão Gênica no Desenvolvimento , Proteostase , Neurogênese/genética , RNA Mensageiro/metabolismo , RNA Mensageiro/genética , Regiões 5' não Traduzidas/genética , Ribossomos/metabolismo , Ribossomos/genética , Humanos , Endorribonucleases/metabolismo , Endorribonucleases/genética , Diferenciação Celular/genética
7.
Artigo em Inglês | MEDLINE | ID: mdl-38906442

RESUMO

BACKGROUND AND AIMS: Cirrhosis patients are at increased risk for postoperative complications. It remains unclear whether preoperative nonsurgical clinician visits improve postoperative outcomes. We assessed the impact of preoperative primary care physician (PCP) and/or gastroenterologist/hepatologist (GI/Hep) visits on postoperative mortality in cirrhosis patients undergoing surgery and explored differences in medication changes and paracentesis rates as potential mediators. METHODS: This was a retrospective cohort study of cirrhosis patients in the Veterans Health Administration who underwent surgery between 2008 and 2016. We compared 1982 patients with preoperative PCP and/or GI/Hep visits with 1846 propensity-matched patients without preoperative visits. We used Cox regression and Fine and Gray competing risk regression to evaluate the association between preoperative visit type and postoperative mortality at 6 months. RESULTS: Patients with preoperative GI/Hep and PCP visits had a 45% lower hazard of postoperative mortality compared with those without preoperative visits (hazard ratio [HR], 0.55; 95% confidence interval [CI], 0.35-0.87). A smaller effect size was noted with GI/Hep preoperative visit alone (HR, 0.69; 95% CI, 0.48-0.99) or PCP visit alone (HR, 0.70; 95% CI, 0.53-0.93). Patients with preoperative PCP/GI/Hep visits were more likely to have diuretics, spontaneous bacterial peritonitis prophylaxis, and hepatic encephalopathy medications newly initiated and/or dose adjusted and more likely to receive preoperative paracentesis as compared with those without preoperative visits. CONCLUSIONS: Preoperative PCP/GI/Hep visits are associated with a reduced risk of postoperative mortality with the greatest risk reduction observed in those with both PCP and GI/Hep visits. This synergistic effect highlights the importance of a multidisciplinary approach in the preoperative care of cirrhosis patients.

8.
Plast Reconstr Surg ; 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38923894

RESUMO

BACKGROUND: Autologous nasoseptal cartilage grafts are used to correct nasal asymmetry and deviation in rhinoplasty, but patients who have undergone multiple surgeries may have limited autologous cartilage tissue available. 3D-printed L-strut implants may address these challenges in the future, but their mechanical strength is understudied. Silk fibroin-gelatin (SFG), polycaprolactone (PCL), and polylactide (PLA) are bio-inks known for their strength. We present Finite Element Analysis (FEA) models comparing the mechanical strength of 3D-printed SFG, PCL, and PLA implants with nasoseptal cartilage grafts when autologous or allografts are not available. METHODS: FEA models compared the stress and deformation responses of 3D-printed solid and scaffold implant replacements to cartilage. To simulate a daily force from overlying soft tissue, a unidirectional load was applied at the "keystone" region given its structural role and compared with native cartilaginous properties. RESULTS: 3D-printed solid SFG, PCL, and PLA and scaffold PCL and PLA models demonstrated lower deformations compared to cartilage. Solid SFG balanced strength and flexibility. The maximum stress was below all materials' yield stresses suggesting their deformations are unlikely permanent under a daily load. CONCLUSIONS: Our FEA models suggest that 3D-printed L-strut implants carry promising mechanical strength. Solid SFG's results mimicked cartilage's mechanical behavior. Thus, scaffold SFG merits further geometric optimization for potential use for cartilage substitution. 3D-printed septal cartilage replacement implants can potentially enhance surgical management of patients who lack available donor cartilage in select settings. CLINICAL RELEVANCE STATEMENT: Computational simulations can evaluate 3D-printed implant strength and their potential to replace septal cartilage in septorhinoplasty.

9.
J Mater Chem B ; 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38935038

RESUMO

Silk sericin (SS) has a long history as a by-product of the textile industry. SS has emerged as a sustainable material for biomedical engineering due to its material properties including water solubility, diverse impact on biological activities including antibacterial and antioxidant properties, and ability to promote cell adhesion and proliferation. This review addresses the origin, structure, properties, extraction, and underlying functions of this protein. An overview of the growing research studies and market evolution is presented, along with highlights of the most common fabrication matrices (hydrogels, bioinks, porous and fibrous scaffolds) and tissue engineering applications. Finally, the future trends with this protein as a multifaceted toolbox for bioengineering are explored, along with the challenges with SS. Overall, the present review can serve as a foundation for the creation of innovative biomaterials utilizing SS as a fundamental building block that hold market potential.

10.
Int J Biol Macromol ; 274(Pt 1): 133271, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38906349

RESUMO

Biofilm formation on indwelling medical devices such as catheters and ventilators due to the adhesion of bacteria poses significant challenges in healthcare. Surface modification with micro- and nano-structures offers a promising strategy to prevent bioadhesion and is safer than surface chemical modification approaches. Here, catheters were prepared using silk fibroin (SF) hydrogels and an infusion molding method, with the inner surface featuring a micropapillae structure inspired by lotus leaves (SF-CMP). After phenylethanol (PEA) fumigation treatment, the resulting catheters (SF-CMP PEA) displayed improved swelling resistance and mechanical properties compared to methanol-treated catheters (SF-CMP MeOH). PEA was more efficient than methanol in controlling the size, distribution, and content of silk crystalline ß-sheet blocks and thus the swelling and mechanical properties. Moreover, the micro-papillae structure on SF-CMP PEA remained stable over 35 days in solution, in contrast to SF-CMP MeOH, which lasted <7 days. SF-CMP PEA exhibited repellent effects against E. coli and S. aureusin vitro, and low cytotoxicity to the endothelial cells cultured on the unpatterned surface. Additionally, subcutaneous implantation studies showed reduced inflammation around the micropatterned samples compared to controls with a plain, unpatterned surface. The unique properties of SF-based materials, including tunable structures, biocompatibility, degradation, and drug-loading capability make them an attractive material for anti-bioadhesion in applications ranging from indwelling medical devices to tissue engineering scaffolds.

11.
ACS Biomater Sci Eng ; 10(7): 4311-4322, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38718147

RESUMO

Encapsulation of single cells is a powerful technique used in various fields, such as regenerative medicine, drug delivery, tissue regeneration, cell-based therapies, and biotechnology. It offers a method to protect cells by providing cytocompatible coatings to strengthen cells against mechanical and environmental perturbations. Silk fibroin, derived from the silkworm Bombyx mori, is a promising protein biomaterial for cell encapsulation due to the cytocompatibility and capacity to maintain cell functionality. Here, THP-1 cells, a human leukemia monocytic cell line, were encapsulated with chemically modified silk polyelectrolytes through electrostatic layer-by-layer deposition. The effectiveness of the silk nanocoating was assessed using scanning electron microscopy (SEM) and confocal microscopy and on cell viability and proliferation by Alamar Blue assay and live/dead staining. An analysis of the mechanical properties of the encapsulated cells was conducted using atomic force microscopy nanoindentation to measure elasticity maps and cellular stiffness. After the cells were encapsulated in silk, an increase in their stiffness was observed. Based on this observation, we developed a mechanical predictive model to estimate the variations in stiffness in relation to the thickness of the coating. By tuning the cellular assembly and biomechanics, these encapsulations promote systems that protect cells during biomaterial deposition or processing in general.


Assuntos
Bombyx , Sobrevivência Celular , Humanos , Sobrevivência Celular/efeitos dos fármacos , Animais , Seda/química , Células THP-1 , Fibroínas/química , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Proliferação de Células/efeitos dos fármacos , Encapsulamento de Células/métodos
12.
JCO Clin Cancer Inform ; 8: e2300159, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38728613

RESUMO

PURPOSE: We present and validate a rule-based algorithm for the detection of moderate to severe liver-related immune-related adverse events (irAEs) in a real-world patient cohort. The algorithm can be applied to studies of irAEs in large data sets. METHODS: We developed a set of criteria to define hepatic irAEs. The criteria include: the temporality of elevated laboratory measurements in the first 2-14 weeks of immune checkpoint inhibitor (ICI) treatment, steroid intervention within 2 weeks of the onset of elevated laboratory measurements, and intervention with a duration of at least 2 weeks. These criteria are based on the kinetics of patients who experienced moderate to severe hepatotoxicity (Common Terminology Criteria for Adverse Events grades 2-4). We applied these criteria to a retrospective cohort of 682 patients diagnosed with hepatocellular carcinoma and treated with ICI. All patients were required to have baseline laboratory measurements before and after the initiation of ICI. RESULTS: A set of 63 equally sampled patients were reviewed by two blinded, clinical adjudicators. Disagreements were reviewed and consensus was taken to be the ground truth. Of these, 25 patients with irAEs were identified, 16 were determined to be hepatic irAEs, 36 patients were nonadverse events, and two patients were of indeterminant status. Reviewers agreed in 44 of 63 patients, including 19 patients with irAEs (0.70 concordance, Fleiss' kappa: 0.43). By comparison, the algorithm achieved a sensitivity and specificity of identifying hepatic irAEs of 0.63 and 0.81, respectively, with a test efficiency (percent correctly classified) of 0.78 and outcome-weighted F1 score of 0.74. CONCLUSION: The algorithm achieves greater concordance with the ground truth than either individual clinical adjudicator for the detection of irAEs.


Assuntos
Algoritmos , Inibidores de Checkpoint Imunológico , Neoplasias Hepáticas , Humanos , Inibidores de Checkpoint Imunológico/efeitos adversos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/imunologia , Estudos Retrospectivos , Fenótipo , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Doença Hepática Induzida por Substâncias e Drogas/diagnóstico , Carcinoma Hepatocelular/tratamento farmacológico , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/diagnóstico , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/etiologia , Fígado/patologia , Fígado/efeitos dos fármacos , Fígado/imunologia
13.
bioRxiv ; 2024 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-38712117

RESUMO

Tissue engineering is a dynamic field focusing on the creation of advanced scaffolds for tissue and organ regeneration. These scaffolds are customized to their specific applications and are often designed to be complex, large structures to mimic tissues and organs. This study addresses the critical challenge of effectively characterizing these thick, optically opaque scaffolds that traditional imaging methods fail to fully image due to their optical limitations. We introduce a novel multi-modal imaging approach combining ultrasound, photoacoustic, and acoustic radiation force impulse imaging. This combination leverages its acoustic-based detection to overcome the limitations posed by optical imaging techniques. Ultrasound imaging is employed to monitor the scaffold structure, photoacoustic imaging is employed to monitor cell proliferation, and acoustic radiation force impulse imaging is employed to evaluate the homogeneity of scaffold stiffness. We applied this integrated imaging system to analyze melanoma cell growth within silk fibroin protein scaffolds with varying pore sizes and therefore stiffness over different cell incubation periods. Among various materials, silk fibroin was chosen for its unique combination of features including biocompatibility, tunable mechanical properties, and structural porosity which supports extensive cell proliferation. The results provide a detailed mesoscale view of the scaffolds' internal structure, including cell penetration depth and biomechanical properties. Our findings demonstrate that the developed multimodal imaging technique offers comprehensive insights into the physical and biological dynamics of tissue-engineered scaffolds. As the field of tissue engineering continues to advance, the importance of non-ionizing and non-invasive imaging systems becomes increasingly evident, and by facilitating a deeper understanding and better characterization of scaffold architectures, such imaging systems are pivotal in driving the success of future tissue-engineering solutions.

16.
Biomimetics (Basel) ; 9(5)2024 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-38786496

RESUMO

Silk and silk derivatives have emerged as a possible alternative in surgical device development, offering mechanical strength, biocompatibility, and environmental sustainability. Through a systematic review following PRISMA guidelines, this study evaluated silk fibroin's application across pre-clinical and clinical settings, focusing on its role as screws and plates for osteofixation. A comprehensive search yielded 245 studies, with 33 subjected to full-text review and 15 ultimately included for qualitative analysis. The findings underscore silk fibroin's superior properties, including its tunable degradation rates and ability to be functionalized with therapeutic agents. In vivo and in vitro studies demonstrated its efficacy in enhancing bone healing, offering improved outcomes in osteofixation, particularly for craniofacial defects. Silk fibroin's remarkable attributes in biodegradation and drug release capabilities underscore its potential to enhance patient care. Ultimately, silk fibroin's integration into surgical practices promises a revolution in patient outcomes and environmental sustainability. Its versatility, coupled with the continuous progress in fabrication techniques, signals a promising horizon for its widespread acceptance in the medical field, potentially establishing a new benchmark in surgical treatment. Further research is expected to solidify the transition of silk products from basic science to patient care, paving the way for widespread use in various surgical applications.

19.
ACS Biomater Sci Eng ; 10(5): 2945-2955, 2024 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-38669114

RESUMO

Metal-coordination bonds, a highly tunable class of dynamic noncovalent interactions, are pivotal to the function of a variety of protein-based natural materials and have emerged as binding motifs to produce strong, tough, and self-healing bioinspired materials. While natural proteins use clusters of metal-coordination bonds, synthetic materials frequently employ individual bonds, resulting in mechanically weak materials. To overcome this current limitation, we rationally designed a series of elastin-like polypeptide templates with the capability of forming an increasing number of intermolecular histidine-Ni2+ metal-coordination bonds. Using single-molecule force spectroscopy and steered molecular dynamics simulations, we show that templates with three histidine residues exhibit heterogeneous rupture pathways, including the simultaneous rupture of at least two bonds with more-than-additive rupture forces. The methodology and insights developed improve our understanding of the molecular interactions that stabilize metal-coordinated proteins and provide a general route for the design of new strong, metal-coordinated materials with a broad spectrum of dissipative time scales.


Assuntos
Histidina , Simulação de Dinâmica Molecular , Níquel , Histidina/química , Níquel/química , Elastina/química , Proteínas/química , Peptídeos/química
20.
Eur J Clin Invest ; 54(8): e14207, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38558028

RESUMO

BACKGROUND: Cytometric analysis has been commonly used to delineate distinct cell subpopulations among peripheral blood mononuclear cells by the differential expression of surface receptors. This capability has reached its apogee with high-dimensional approaches such as mass cytometry and spectral cytometry that include simultaneous assessment of 20-50 analytes. Unfortunately, this approach also engenders significant complexity with analytical and interpretational pitfalls. METHODS: Here, we demonstrate a complementary approach with restricted-dimensionality to assess cell-type specific intracellular molecular expression levels at exceptional levels of precision. The expression of five analytes was individually assessed in four mononuclear cell-types from peripheral blood. RESULTS: Distinctions in expression levels were seen between cell-types and between samples from different donor groups. Mononuclear cell-type specific molecular expression levels distinguished pregnant from nonpregnant women and G-CSF-treated from untreated persons. Additionally, the precision of our analysis was sufficient to quantify a novel relationship between two molecules-Rel A and translocator protein-by correlational analysis. CONCLUSIONS: Restricted-dimensional cytometry can provide a complementary approach to define characteristics of cell-type specific intracellular protein and phosphoantigen expression in mononuclear cells.


Assuntos
Citometria de Fluxo , Leucócitos Mononucleares , Humanos , Feminino , Leucócitos Mononucleares/metabolismo , Gravidez , Adulto , Masculino
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