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2.
Biomed Mater ; 19(3)2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38574581

RESUMO

In terms of biomedical tools, nanodiamonds (ND) are a more recent innovation. Their size typically ranges between 4 to 100 nm. ND are produced via a variety of methods and are known for their physical toughness, durability, and chemical stability. Studies have revealed that surface modifications and functionalization have a significant influence on the optical and electrical properties of the nanomaterial. Consequently, surface functional groups of NDs have applications in a variety of domains, including drug administration, gene delivery, immunotherapy for cancer treatment, and bio-imaging to diagnose cancer. Additionally, their biocompatibility is a critical requisite for theirin vivoandin vitrointerventions. This review delves into these aspects and focuses on the recent advances in surface modification strategies of NDs for various biomedical applications surrounding cancer diagnosis and treatment. Furthermore, the prognosis of its clinical translation has also been discussed.


Assuntos
Nanodiamantes , Neoplasias , Humanos , Nanodiamantes/química , Nanodiamantes/uso terapêutico , Sistemas de Liberação de Medicamentos/métodos , Neoplasias/terapia , Neoplasias/tratamento farmacológico , Diagnóstico por Imagem/métodos , Imunoterapia
3.
Chembiochem ; : e202400009, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38545627

RESUMO

Calcium (Ca2+) ions play a crucial role in the functioning of neurons, governing various aspects of neuronal activity such as rapid modulation and alterations in gene expression. Ca2+ signaling has a significant impact on the development of diseases and the impairment of neuronal functions. Herein, the study reports a Ca2+ ion sensor in neuronal cells using a gold nanorod. The gold nanorod (GA-GNR) conjugated glutamic acid developed in the study was used as a nano-bio probe for the experimental and in vitro detection of calcium. The nanosensor is colloidally stable, preserves plasmonic properties, and shows good viability in neuronal cells, as well as promoting neuron cell line growth. The cytotoxicity and cell penetration of the nanosensor are studied using Raman spectroscopy, brightfield and darkfield microscopy imaging, and MTT assays. The quantification of Ca2+ ions in neuronal cells is determined by monitoring the surface plasmon resonance (SPR) of the GA-GNR. The change in the intensity profile in the presence of Ca2+ incubated neurons was effectively used to develop a portable prototype of an optical Ca2+ sensor, proposing it as a tool for neurodegenerative disease diagnosis and neuromodulation evaluation.

4.
J Mater Chem B ; 12(3): 720-729, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38165308

RESUMO

Nanoarchitectonics, an emerging strategy, presents a promising alternative for developing highly efficient next-generation functional materials. Multifunctional materials developed using nanoarchitectonics help to mimic biological molecules. Porphyrin-based molecules can be effectively utilized to design such assemblies. Metal nanocluster is one of the functional materials that can shed more insight into developing nanoarchitectonic materials. Herein, an inherently near-infrared (NIR) fluorescing copper nanocluster (CuC)-mediated structural assembly via protoporphyrin IX (PPIX) and doxorubicin (Dox) is demonstrated as the functional material. Dox-loaded porphyrin-mediated CuC assembly shows singlet oxygen generation and 66% drug release at 15 min. Furthermore, the efficacy of this material is tested for cancer diagnosis and bimodal therapeutic strategy due to the fluorescing ability of the cluster and loading of PPIX as well as the drug, respectively. The nanoarchitecture exhibits targeted imaging and 83% cell death in HeLa cells upon laser irradiation with 10 nmoles and 20 nmoles of PPIX and Dox, respectively.


Assuntos
Neoplasias , Porfirinas , Humanos , Cobre/química , Porfirinas/farmacologia , Células HeLa , Medicina de Precisão , Doxorrubicina/química , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico
5.
Regen Biomater ; 10: rbad099, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38020235

RESUMO

Muscle degeneration is one the main factors that lead to the high rate of retear after a successful repair of rotator cuff (RC) tears. The current surgical practices have failed to treat patients with chronic massive rotator cuff tears (RCTs). Therefore, regenerative engineering approaches are being studied to address the challenges. Recent studies showed the promising outcomes of electroactive materials (EAMs) on the regeneration of electrically excitable tissues such as skeletal muscle. Here, we review the most important biological mechanism of RC muscle degeneration. Further, the review covers the recent studies on EAMs for muscle regeneration including RC muscle. Finally, we will discuss the future direction toward the application of EAMs for the augmentation of RCTs.

6.
Proc Natl Acad Sci U S A ; 120(45): e2309156120, 2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-37903261

RESUMO

Cobalt-containing alloys are useful for orthopedic applications due to their low volumetric wear rates, corrosion resistance, high mechanical strength, hardness, and fatigue resistance. Unfortunately, these prosthetics release significant levels of cobalt ions, which was only discovered after their widespread implantation into patients requiring hip replacements. These cobalt ions can result in local toxic effects-including peri-implant toxicity, aseptic loosening, and pseudotumor-as well as systemic toxic effects-including neurological, cardiovascular, and endocrine disorders. Failing metal-on-metal (MoM) implants usually necessitate painful, risky, and costly revision surgeries. To treat metallosis arising from failing MoM implants, a synovial fluid-mimicking chelator was designed to remove these metal ions. Hyaluronic acid (HA), the major chemical component of synovial fluid, was functionalized with British anti-Lewisite (BAL) to create a chelator (BAL-HA). BAL-HA effectively binds cobalt and rescues in vitro cell vitality (up to 370% of cells exposed to IC50 levels of cobalt) and enhances the rate of clearance of cobalt in vivo (t1/2 from 48 h to 6 h). A metallosis model was also created to investigate our therapy. Results demonstrate that BAL-HA chelator system is biocompatible and capable of capturing significant amounts of cobalt ions from the hip joint within 30 min, with no risk of kidney failure. This chelation therapy has the potential to mitigate cobalt toxicity from failing MoM implants through noninvasive injections into the joint.


Assuntos
Artroplastia de Quadril , Prótese de Quadril , Humanos , Prótese de Quadril/efeitos adversos , Ácido Hialurônico , Dimercaprol , Terapia por Quelação , Falha de Prótese , Artroplastia de Quadril/efeitos adversos , Metais , Cobalto , Quelantes/uso terapêutico , Íons
7.
ACS Biomater Sci Eng ; 9(10): 5782-5792, 2023 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-37769114

RESUMO

The high retear rate after a successful repair of the rotator cuff (RC) is a major clinical challenge. Muscle atrophy and fat accumulation of RC muscles over time adversely affect the rate of retear. Since current surgical techniques do not improve muscle degenerative conditions, new treatments are being developed to reduce muscle atrophy and fat accumulation. In the previous study, we have shown the efficacy of aligned electroconductive nanofibrous fabricated by coating poly(3,4-ethylene dioxythiophene): poly(styrenesulfonate) (PEDOT:PSS) nanoparticles onto aligned poly(ε-caprolactone) (PCL) electrospun nanofibers (PEDOT:PSS matrix) to reduce muscle atrophy in acute and subacute models of RC tears (RCTs). In this study, we further evaluated the efficacy of the PEDOT:PSS matrix to reduce muscle atrophy and fat accumulation in a rat model of chronic massive full-thickness RCTs (MRCTs). The matrices were transplanted on the myotendinous junction to the belly of the supraspinatus and infraspinatus muscles at 16 weeks after MRCTs. The biomechanics and histological assessments showed the potential of the PEDOT:PSS matrix to suppress the progression of muscle atrophy, fat accumulation, and fibrosis in both supraspinatus and infraspinatus muscles at 24 and 32 weeks after MRCTs. We also demonstrated that the PEDOT:PSS matrix implantation significantly improved the tendon morphology and tensile properties compared with current surgical techniques.


Assuntos
Lesões do Manguito Rotador , Ratos , Animais , Lesões do Manguito Rotador/cirurgia , Lesões do Manguito Rotador/patologia , Ombro/patologia , Manguito Rotador/cirurgia , Manguito Rotador/patologia , Atrofia Muscular/patologia , Tendões/patologia
8.
Ther Adv Vaccines Immunother ; 11: 25151355231190497, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37645011

RESUMO

Background: Patients with plasma cell dyscrasia are at a higher risk of developing a severe Coronavirus-2019 (COVID-19) infection. Here we present a systematic review of clinical studies focusing on the immune response to the COVID-19 vaccination in patients with plasma cell dyscrasia. Objectives: This study aims to evaluate the immune response to COVID-19 vaccines in patients with plasma cell dyscrasia and to utilize the results to improve day-to-day practice. Design: Systematic Review. Methods: Online databases (PubMed, CINAHL, Ovid, and Cochrane) were searched following the preferred reporting items for systematic review and meta-analysis (PRISMA) guidelines. Only articles published in the English language were included. Out of 59 studies, nine articles (seven prospective and two retrospective studies) were included in this systematic review. Abstracts, case reports, and case series were excluded. Results: In all nine studies (N = 1429), seroconversion post-vaccination was the primary endpoint. Patients with plasma cell disorders had a lower seroconversion rate compared to healthy vaccinated individuals and the overall percentage of seroconversion ranged between 23% and 95.5%. Among patients on active therapy, lower seroconversion rates were seen on an anti-CD38 agent, ranging from 6.5 up to 100%. In addition, a significantly lower percentage was recorded in older patients, especially in those aged equal to or greater than 65 years and those who have been treated with multiple therapies previously. Only one study reported a statistically significant better humoral response rate with the mRNA vaccine compared to ADZ1222/Ad26.Cov.S. Conclusion: Variable seropositive rates are seen in patients with plasma cell dyscrasia. Lower rates are reported in patients on active therapy, anti-CD38 therapy, and elderly patients. Hence, we propose patients with plasma cell dyscrasias should receive periodic boosters to maintain clinically significant levels of antibodies against COVID-19. Registration: PROSPERO ID: CRD42023404989.


COVID-19 vaccine immune response in patients with plasma cell dyscrasia- a systematic review Background: Patients with plasma cell disorders are at a higher risk of developing a severe coronavirus-19 infection. Here we present a systematic review of clinical studies focusing on the immune response to the coronavirus-19 vaccination in patients with plasma cell dyscrasia. Objectives: This study aims to evaluate the immune response to COVID-19 vaccines in patients with plasma cell dyscrasia and to transcribe the results to day-to-day practice. Design: Systematic Review Data sources: PubMed, CINAHL, Ovid, and Cochrane. Methods: Online databases were searched following the preferred reporting items for systematic review and meta-analysis (PRISMA) guidelines. Only articles published in the English language were included. Abstracts, case reports, and case series were excluded. Out of 59 studies, nine articles were selected for a systematic review. Results: In all 9 studies (N = 1,429), seroconversion post-vaccination was the primary endpoint that our review assessed. Patients with plasma cell disorders had a lower seroconversion rate compared to healthy vaccinated individuals and the overall percentage of seroconversion ranged between 23 and 95.5%. Amongst patients on active therapy, lower seroconversion rates were seen in patients on an anti-CD38 agent, ranging from 6.5 up to 100%. In addition, a significantly lower percentage was recorded in older patients, especially those aged equal to or greater than 65 years and those who have been treated with multiple therapies previously. Only one study reported a statistically significant better humoral response rate with the mRNA vaccine compared to ADZ1222/Ad26.Cov.S. Conclusion: Variable seropositive rates are seen in patients with plasma cell dyscrasia. Lower rates are reported in patients on active therapy, anti-CD38 therapy, and elderly patients. Hence, we propose patients with plasma cell disorders should receive periodic boosters to maintain clinically significant levels of antibodies against COVID-19.

9.
Dalton Trans ; 52(24): 8488, 2023 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-37282662

RESUMO

Correction for 'An insight into the optical properties of a sub nanosize glutathione stabilized gold cluster' by Lakshmi V. Nair et al., Dalton Trans., 2016, 45, 11286-11291, https://doi.org/10.1039/C6DT01753C.

10.
ACS Appl Bio Mater ; 6(6): 2029-2042, 2023 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-37261398

RESUMO

Arthroplasty implants can undergo corrosion at the modular components, trunnion, and hinges, owing to implant material makeup, micromotion, and interaction with body fluid. In this review, various mechanisms of corrosion in arthroplasty were explored with suggestions on means of improvement. We identified 10 methods including pitting, crevice, mechanically assisted crevice corrosion, fretting, fretting initiated crevice corrosion, mechanically assisted taper corrosion, galvanic corrosion, stress/tension, fatigue corrosion, and inflammatory cell induced corrosion. The position of implants on the galvanic series, and their ability to maintain passivation contribute to their longevity in service. Due to the relative motion of arthroplastic components, bio-tribocorrosion may disrupt passive oxide films, and pitting is initiated at interfaces. Thus, corrosion in arthroplasty as an electrochemical phenomenon mainly starts on one spot and progresses in 3 steps: (1) the oxidative dissolution of metal from implant surfaces into the aqueous active environment, releasing cations, (2) the attraction of electrons to the opposite charge created at another point of the implant surface, producing current flow, and (3) the formation of oxides of metal and metal hydroxides deposited as rust at the surface of the implant. Recent innovations in material manufacturing continue to improve the efficiency of arthroplasty; however, the component parts remain susceptible to bio-tribocorrosion. Thus, a complete eradication of corrosion in arthroplasty would require futuristic materials with improvement in recent materials and designs, derived from knowledge of existing retrieved implants, and strategies to provide overall surface finishes that protect against bio-tribocorrosion.


Assuntos
Metais , Falha de Prótese , Humanos , Corrosão , Desenho de Prótese , Artroplastia , Óxidos
11.
Cureus ; 15(5): e39213, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37342745

RESUMO

Objective The purpose of this study was to document sleep quality and assess its sociodemographic, behavioral (i.e., tobacco use, alcohol use, and screen time), and mental-health-related indicators (i.e., anxiety and depression) in adults aged 30-59 years across three states of India, and to geo-locate state and district-level findings of sleep quality during the ongoing coronavirus disease 2019 (COVID-19) pandemic. Methods From October 2020 to April 2021, residents (aged 30-59 years) of Kerala, Madhya Pradesh, and Delhi completed a web-based survey that included sociodemographic and behavioral factors, clinical history of COVID-19, and mental health screening instruments for anxiety and depression, namely the Generalized Anxiety Disorder 2-item (GAD-2) and Patient Health Questionnaire-2 (PHQ-2). The Pittsburgh Sleep Quality Index (PSQI) was used to evaluate the quality of sleep. Average PSQI scores were geo-mapped. Results Of the 694 participants who responded, 647 completed the PSQI. The mean (SD) global PSQI score was 5.99 (3.2), with approximately 54% of participants reporting poor sleep quality (PSQI Score>5). Eight hotspot districts with severe sleep disturbances (mean score PSQI>6.5) were identified. Multivariable logistic regression analysis showed that compared to Madhya Pradesh, participants from Kerala and Delhi had 62% and 33% lower chances of having poor sleep quality, respectively. Those who screened positive for anxiety had higher odds of having poor sleep quality (adjusted odds ratio {aOR}=2.4, P=0.006*). Conclusion Overall, sleep quality was poor during the early stages of the COVID-19 pandemic (October 2020-April 2021), especially among those who reported high levels of anxiety. Among the three included states, there were differences in sleep quality.

12.
Biochim Biophys Acta Gen Subj ; 1867(6): 130361, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37019341

RESUMO

Breast cancer is the most common ailment among women. In 2020, it had the highest incidence of any type of cancer. Many Phase II and III anti-cancer drugs fail due to efficacy, durability, and side effects. Thus, accelerated drug screening models must be accurate. In-vivo models have been used for a long time, but delays, inconsistent results, and a greater sense of responsibility among scientists toward wildlife have led to the search for in-vitro alternatives. Stromal components support breast cancer growth and survival. Multi-compartment Transwell models may be handy instruments. Co-culturing breast cancer cells with endothelium and fibroblasts improves modelling. The extracellular matrix (ECM) supports native 3D hydrogels in natural and polymeric forms. 3D Transwell cultured tumor spheroids mimicked in-vivo pathological conditions. Tumor invasion, migration, Trans-endothelial migration, angiogenesis, and spread are studied using comprehensive models. Transwell models can create a cancer niche and conduct high-throughput drug screening, promising future applications. Our comprehensive shows how 3D in-vitro multi compartmental models may be useful in producing breast cancer stroma in Transwell culture.


Assuntos
Antineoplásicos , Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Modelos Epidemiológicos , Técnicas de Cocultura , Matriz Extracelular
13.
Breast Dis ; 42(1): 27-36, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36872762

RESUMO

BACKGROUND: Endocrine treatment for breast cancer acts largely by inhibiting tumor cell proliferation. The biomarker Ki67 is linked to the proliferative index of the tumour. OBJECTIVE: To identify the factors affecting the fall in Ki67 value in early-stage hormone receptor (HR) positive breast cancer patients receiving short-term preoperative endocrine therapy in an Indian cohort. METHODS: Women with hormone receptor positive, invasive, nonmetastatic, and early breast cancer (4 week) did not affect the fall in Ki67. CONCLUSION: Preoperative therapy with Letrozole resulted in a more significant fall in Ki67, as compared to therapy with Tamoxifen. Determining the fall in Ki67 value in response to preoperative endocrine therapy could provide an insight into the response to endocrine therapy in luminal breast cancer.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Antígeno Ki-67 , Letrozol , Tamoxifeno , Estrogênios
14.
Indian J Surg Oncol ; 14(1): 122-127, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36891414

RESUMO

Ki67 index is considered to be a reliable indicator of the proliferative activity of breast cancer. Additionally, the Ki67 proliferative marker may play a role in assessing response to systemic therapeutic strategies and can act as a prognostic biomarker. But its limited reproducibility which stems from a lack of standardization of procedures, inter-observer variability, and preanalytical and analytical variabilities all have hampered the use of the Ki67 index in clinical practice. Currently, clinical trials have been evaluating Ki67 as a predictive marker for needing adjuvant chemotherapy in luminal early breast cancer patients receiving neoadjuvant endocrine therapy. But the inconsistencies existing in the estimation of the Ki67 index limit the utility of Ki67 in standard clinical practice. The purpose of this review is to evaluate the benefits and drawbacks of utilizing Ki-67 in early-stage breast cancer to prognosticate the disease and predict the risk of recurrence.

15.
Indian J Surg Oncol ; 14(1): 208-214, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36891439

RESUMO

Endocrine treatment for breast cancer acts largely by inhibiting tumor cell proliferation. The study aimed to explore the fall in proliferative marker Ki67 in patients receiving preoperative endocrine therapy and the factors associated with it. A prospective series of hormone receptor-positive postmenopausal women with early N0/N1 breast cancer were enrolled. Patients were requested to take letrozole OD while they await surgery. The fall in Ki67 after the endocrine therapy was defined as the percentage of the difference between the pre-and postoperative Ki67 value with the preoperative Ki67. Sixty cases matched the criteria of which 41 (68.3%) of women showed a good response to preoperative letrozole (fall in Ki67 > 50%; p-value < 0.001). The average mean fall in Ki67 was 57.083 ± 37.97. Postoperative Ki67 after the therapy was less than 10% in 39 (65%) patients. Ten patients (16.6%) had a low Ki67 index at baseline, which continued to remain low after preoperative endocrine therapy. The duration of the therapy did not affect the percentage of Ki67 fall in our study. Short-term changes in the Ki67 index in the neoadjuvant settings may predict outcomes during adjuvant use of the same treatment. Proliferation index on residual tumor holds prognostic importance, and our results reflect that greater attention should be given to the percentage of reduction of Ki67, rather than focusing purely on a fixed value. This could help predict patients who respond well to endocrine therapy, while those who respond poorly may require further adjuvant treatment.

16.
Artigo em Inglês | MEDLINE | ID: mdl-36817306

RESUMO

Introduction: Controversies remain regarding the safety of tocilizumab in the treatment of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. In this study, we seek to describe the infectious complications after tocilizumab in COVID patients and determine the related risk factors. Methods: A single-center retrospective observational study was conducted among adult patients with SARS-CoV-2 infection admitted between 06/01/2020 and 12/31/2021 who received tocilizumab at our institution. Baseline demographics and laboratory values are obtained through reviewing electronic medical records. Risk factors of infectious complications after tocilizumab are identified through regression analysis. Statistics are performed using SPSS. P-value <0.05 is considered statistically significant. Results: Out of the 52 patients identified, infectious complications after tocilizumab were documented in 30 patients (57.7%). The most common infections include pneumonia, urinary tract infections, and bacteremia of unknown sources. Overall mortality was 42.3%. Through multivariate regression analysis, age more than 65, hyperglycemia on admission, and tocilizumab administration more than 2 days after hospital admission are independent risk factors associated with developing infections. Conclusions: In real-world experience, infectious complications are not uncommon in COVID patients who receive tocilizumab. Early use of tocilizumab may be of benefit. More rigorous patient selection and monitoring should be explored in future studies.

17.
Front Oncol ; 13: 1034205, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36761981

RESUMO

It is well known that solid hypoxic tumour cells oxidise glucose through glycolysis, and the end product of this pathway is fermented into lactate which accumulates in the tumour microenvironment (TME). Initially, it was proclaimed that cancer cells cannot use lactate; therefore, they dump it into the TME and subsequently augment the acidity of the tumour milieu. Furthermore, the TME acts as a lactate sink with stope variable amount of lactate in different pathophysiological condition. Regardless of the amount of lactate pumped out within TME, it disappears immediately which still remains an unresolved puzzle. Recent findings have paved pathway in exploring the main role of lactate acidosis in TME. Cancer cells utilise lactate in the de novo fatty acid synthesis pathway to initiate angiogenesis and invasiveness, and lactate also plays a crucial role in the suppression of immunity. Furthermore, lactate re-programme the lipid biosynthetic pathway to develop a metabolic symbiosis in normoxic, moderately hypoxic and severely hypoxic cancer cells. For instance: severely hypoxic cancer cells enable to synthesizing poly unsaturated fatty acids (PUFA) in oxygen scarcity secretes excess of lactate in TME. Lactate from TME is taken up by the normoxic cancer cells whereas it is converted back to PUFAs after a sequence of reactions and then liberated in the TME to be utilized in the severely hypoxic cancer cells. Although much is known about the role of lactate in these biological processes, the exact molecular pathways that are involved remain unclear. This review attempts to understand the molecular pathways exploited by lactate to initiate angiogenesis, invasiveness, suppression of immunity and cause re-programming of lipid synthesis. This review will help the researchers to develop proper understanding of lactate associated bimodal regulations of TME.

18.
Nanoscale ; 14(37): 13561-13569, 2022 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-36073600

RESUMO

Engineering different nanomaterials into a single functional material can impart unique properties of the parental nanoparticles, especially in the field of bio imaging and therapy. Gold nanomaterials having different sizes, shapes and dimensionalities exhibit exceptional properties apart from their non-toxicity and hence are strong candidates in the biomedical field. Designing a hybrid nanomaterial of two gold nanostructures retaining the individual properties of the parental nanomaterials is challenging. Here, we demonstrate the synthesis of a hybrid nanomaterial (GQC@GNR), comprising an extremely small gold nanocluster and a representative of the asymmetric gold nanostructure, i.e., a gold nanorod, both having their own different exclusive optical properties like tuneable emission and NIR absorption characteristics, respectively. The hybrid system is designed to retain its emission and absorption in the NIR region to use it as an agent for simultaneous imaging and therapy. The formation of GQC@GNR and its architectonics heavily depend on the synthesis route and the parameters adopted which in turn have a direct influence on its properties. The architecture and its connection to the optical properties are explained using UV-Vis absorption and photoluminescence spectroscopy, zeta potential, transmission electron microscopy, etc. DFT-based computational modelling supports architectonics as explained by the experimental findings. The formation of the gold-gold hybrid system witnessed interesting science with a strong indication that materials with desired properties can be designed by appropriately modulating the architectonics of hybrid formation. Finally, folate conjugated GQC@GNR demonstrated its efficacy for targeted imaging and photothermal therapy in HeLa cells and tumor-bearing animal models. The detailed therapeutic efficacy of GQC@GNR is also explained based on Raman spectroscopy.


Assuntos
Ouro , Nanotubos , Animais , Ácido Fólico , Ouro/química , Ouro/farmacologia , Células HeLa , Humanos , Nanotubos/química , Imagem Óptica , Terapia Fototérmica
19.
ACS Appl Mater Interfaces ; 14(38): 42804-42811, 2022 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-36112124

RESUMO

The legalization of hemp cultivation in the United States has caused the price of hemp-derived cannabinoids to decrease 10-fold within 2 years. Cannabidiol (CBD), one of many naturally occurring diols found in hemp, can be purified in high yield for low cost, making it an interesting candidate for polymer feedstock. In this study, two polyesters were synthesized from the condensation of either CBD or cannabigerol (CBG) with adipoyl chloride. Poly(CBD-Adipate) was cast into free-standing films and subjected to thermal, mechanical, and biological characterization. Poly(CBD-Adipate) films exhibited a lack of cytotoxicity toward adipose-derived stem cells while displaying an inherent antioxidant activity compared to poly(lactide) films. Additionally, this material was found to be semi-crystalline and able to be melt-processed into a plastic hemp leaf using a silicone baking mold.


Assuntos
Canabidiol , Canabinoides , Cannabis , Adipatos , Antioxidantes/farmacologia , Canabidiol/farmacologia , Canabinoides/farmacologia , Cannabis/química , Plásticos , Poliésteres/farmacologia , Polímeros , Silicones
20.
Proc Natl Acad Sci U S A ; 119(33): e2208106119, 2022 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-35939692

RESUMO

Massive rotator cuff tears (MRCTs) of the shoulder cause disability and pain among the adult population. In chronic injuries, the tendon retraction and subsequently the loss of mechanical load lead to muscle atrophy, fat accumulation, and fibrosis formation over time. The intrinsic repair mechanism of muscle and the successful repair of the torn tendon cannot reverse the muscle degeneration following MRCTs. To address these limitations, we developed an electroconductive matrix by incorporating graphene nanoplatelets (GnPs) into aligned poly(l-lactic acid) (PLLA) nanofibers. This study aimed to understand 1) the effects of GnP matrices on muscle regeneration and inhibition of fat formation in vitro and 2) the ability of GnP matrices to reverse muscle degenerative changes in vivo following an MRCT. The GnP matrix significantly increased myotube formation, which can be attributed to enhanced intracellular calcium ions in myoblasts. Moreover, the GnP matrix suppressed adipogenesis in adipose-derived stem cells. These results supported the clinical effects of the GnP matrix on reducing fat accumulation and muscle atrophy. The histological evaluation showed the potential of the GnP matrix to reverse muscle atrophy, fat accumulation, and fibrosis in both supraspinatus and infraspinatus muscles at 24 and 32 wk after the chronic MRCTs of the rat shoulder. The pathological evaluation of internal organs confirmed the long-term biocompatibility of the GnP matrix. We found that reversing muscle degenerative changes improved the morphology and tensile properties of the tendon compared with current surgical techniques. The long-term biocompatibility and the ability of the GnP matrix to treat muscle degeneration are promising for the realization of MRCT healing and regeneration.


Assuntos
Grafite , Músculo Esquelético , Atrofia Muscular , Nanopartículas , Lesões do Manguito Rotador , Animais , Fibrose , Grafite/uso terapêutico , Músculo Esquelético/fisiologia , Atrofia Muscular/etiologia , Atrofia Muscular/patologia , Atrofia Muscular/prevenção & controle , Ratos , Ratos Sprague-Dawley , Regeneração , Lesões do Manguito Rotador/complicações , Lesões do Manguito Rotador/patologia , Lesões do Manguito Rotador/cirurgia , Ombro
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