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Graphene and graphene-based materials have been attracted in the past few years for biomedical applications due to their physicochemical and biological properties such as large surface area, chemical and mechanical stability, excellent conductivity, and good biocompatibility. Graphene-based materials not only surface modified graphene-based materials like graphene oxide (GO) or reduced graphene oxide (rGO) but also other structural forms like fullerene, carbon nanotubes, and graphite have been applied to advanced drug delivery systems. In this chapter, we review on the application of graphene-based materials in the drug delivery system with their physicochemical properties, methods for the preparation of graphene-based carriers, followed by analysis about their biodistribution and biosafety whether they are suitable as drug delivery carriers.
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Grafite , Nanoestruturas , Nanotubos de Carbono , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Grafite/química , Nanoestruturas/química , Distribuição TecidualRESUMO
Graphene is sp2-hybridized carbon structure-based two-dimensional (2D) sheet. Graphene-based nanomaterials possess several features such as unique mechanical, electronic, thermal, and optical properties, high specific surface area, versatile surface functionalization, and biocompatibility, which attracted researcher's interests in various fields including biomedicine. In this chapter, we particularly focused on the biomedical imaging applications of graphene-based nanomaterials like graphene oxide (GO), reduced graphene oxide (rGO), graphene quantum dots (GQDs), graphene oxide quantum dots (GOQDs), and other derivatives, which utilize their outstanding optical properties. There are some biomedical imaging modalities using Graphene-based Nanomaterials, among which we will highlight fluorescence imaging, Raman imaging, magnetic resonance imaging, and photoacoustic imaging. We also discussed the brief perspectives and future application related to them.
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Grafite , Nanoestruturas , Pontos Quânticos , Imagem ÓpticaRESUMO
Owing to astonishing properties such as the large surface area to volume ratio, mechanical stability, antimicrobial property, and collagen crosslinking, graphene family nanomaterials (GFNs) have been widely used in various biomedical applications including tissue regeneration. Many review literatures are available to compile the role of GFNs in cardiac, bone, and neuronal tissue regeneration. However, the contribution of GFNs in skin wound healing and tissue regeneration was not yet discussed. In the present review, we have highlighted the properties of GFNs and their application in skin wound healing. In addition, we have included challenges and future directions of GFNs in skin tissue regeneration in the portion of conclusion and perspectives.
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Grafite , Nanoestruturas , Pele , CicatrizaçãoRESUMO
Rotating cylindrical stamp-based nanoimprint technique has many advantages, including the continuous fabrication of intriguing micro/nanostructures and rapid pattern transfer on a large scale. Despite these advantages, the previous nanoimprint lithography has rarely been used for producing sophisticated nanoscale patterns on a non-planar substrate that has many extended applications. Here, the simple integration of nanoimprinting process with a help of a transparent stamp wrapped on the cylindrical roll and UV optical source in the core to enable high-throughput pattern transfer, particularly on a fabric substrate is demonstrated. Moreover, as a functional resin material, this innovative strategy involves a synergistic approach on the synthesis of molecularly imprinted polymer, which are spatially organized free-standing perforated nanostructures such as nano/microscale lines, posts, and holes patterns on various woven or nonwoven blank substrates. The proposed materials can serve as a self-encoded filtration medium for selective separation of formaldehyde molecules. It is envisioned that the combinatorial fabrication process and attractive material paves the way for designing next-generation separation systems in use to capture industrial or household toxic substances.
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Polímeros Molecularmente Impressos , Nanoestruturas , ImpressãoRESUMO
Although nanocarriers containing perfluorocarbon (PFC) have been widely investigated as an ultrasound (US) imaging agent and a high intensity focused ultrasound (HIFU) agent, these carriers have suffered from low stability and biocompatibility limiting their further biomedical applications. Here, we developed surface cross-linked polymer nanodroplets as a HIFU therapeutic agent guided by bimodal photoacoustic (PA) and US imaging. Pluronic F127 was reacted with 4-nitrophenyl chloroformate (NPC) and mixed with naphthalocyanine (Nc) in dichloromethane, which was added into the aqueous solution of amine-functionalized six-arm-branched poly(ethylene glycol) (PEG) to form an oil-in-water emulsion for the cross-linking reaction between the terminal NPC of Pluronic F127 and the primary amine of six-arm PEG. The resulting solution was sonicated with liquid perfluorohexane (PFH) to prepare PEG cross-linked Pluronic F127 nanoparticles encapsulating Nc and PFH (Nc/PFH@PCPN). Nc/PFH@PCPN appeared to be stable without any coalescence or vaporization in the physiological condition. Upon the application of HIFU, Nc/PFH@PCPN was vaporized and showed increased US intensity for 180 min. The Nc dye in the nanodroplets enabled the stable encapsulation of PFH and the bimodal US/PA imaging. In vivo PA/US image-guided HIFU ablation therapy confirmed that the nanodroplets increased the cavitation effect, induced necrosis and apoptosis of tumor cells, and reduced tumor growth significantly for 12 days. Taken together, the multifunctional Nc/PFH@PCPN was successfully developed as a new platform for PA/US image-guided HIFU therapy.
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Meios de Contraste/química , Tratamento por Ondas de Choque Extracorpóreas/métodos , Fluorocarbonos/química , Nanocápsulas/química , Porfirinas/química , Ultrassonografia/métodos , Animais , Bovinos , Clorobenzoatos/química , Meios de Contraste/administração & dosagem , Fluorocarbonos/administração & dosagem , Humanos , Células MCF-7 , Camundongos , Camundongos Endogâmicos BALB C , Técnicas Fotoacústicas/métodos , Poloxâmero/química , Polietilenoglicóis/química , Porfirinas/administração & dosagem , VolatilizaçãoRESUMO
Epidemiologic studies have indicated that albuminuria is associated with mortality from all causes and cardiovascular disease (CVD), with substantial heterogeneity. We evaluated if the associations of urine albumin creatinine ratio (ACR) with all-cause and CVD mortality differed depending on serum concentrations of persistent organic pollutants (POPs), strong lipophilic chemical mixtures with very long half-lives, which are recently linked to many degenerative diseases. Study subjects were participants of the National Health and Nutrition Examination Survey 1999-2004 who were 60 years or older at baseline (n=1215 and 1067 for organochlorine pesticides (OCPs) and other POPs, respectively). They were followed-up through 2011 (mean follow-up periods: 8.1 and 8.0 years for OCPs and other POPs, respectively). The associations between the ACR and all-cause mortality significantly differed by the serum levels of POPs, especially organochlorine pesticides (OCPs; Pinteraction<0.01). Stratified analyses indicated that the associations between ACR and all-cause mortality became stronger as the serum levels of OCPs increased. Among the elderly with the highest tertile of OCPs, the adjusted hazard ratios were 1.0, 1.1, and 2.9 (Ptrend<0.01) across the categories of ACR (<10, 10-<30, and ≥30mg/g); however, ACR was not clearly related to mortality among the elderly with the lowest tertile of OCPs. CVD mortality showed similar interactions, as noted for all-cause mortality (Pinteraction<0.01). The different associations between albuminuria and mortality by the serum OCP levels and the little association among the elderly with low serum OCPs levels suggest that OCPs play an important role in albuminuria-related death risk. However, these findings need to be replicated in other cohort studies.
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Albuminúria/sangue , Albuminúria/mortalidade , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/mortalidade , Poluentes Ambientais/sangue , Hidrocarbonetos Clorados/sangue , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos NutricionaisRESUMO
Vaccines are commonly administered by injection using needles. Although transdermal microneedles are less-invasive promising alternatives, needle-free topical vaccination without involving physical damage to the natural skin barrier is still sought after as it can further reduce needle-induced anxiety and simply administration. However, this long-standing goal has been elusive since the intact skin is impermeable to most macromolecules. Here, we show an efficient, non-invasive transdermal vaccination in mice by employing two key innovations: first, the use of hyaluronan (HA) as vaccine carriers and, second, non-ablative laser adjuvants. Conjugates of a model vaccine ovalbumin (OVA) and HA-HA-OVA conjugates-induced more effective maturation of dendritic cells in vitro, compared to OVA or HA alone, through synergistic HA receptor-mediated effects. Following topical administration in the back skin, HA-OVA conjugates penetrated into the epidermis and dermis in murine and porcine skins up to 30% of the total applied quantity, as revealed by intravital microscopy and quantitative fluorescence assay. Topical administration of HA-OVA conjugates significantly elevated both anti-OVA IgG antibody levels in serum and IgA antibody levels in bronchioalveolar lavage, with peak levels at 4 weeks, while OVA alone had a negligible effect. An OVA challenge at week 8 elicited strong immune-recall humoral responses. With pre-treatment of the skin using non-ablative fractional laser beams (1410 nm wavelength, 10 ms pulse duration, 0.2 mJ/pulse) as laser adjuvant, strong immunization was achieved with much reduced doses of HA-OVA (1 mg/kg OVA). Our results demonstrate the potential of the non-invasive patch-type transdermal vaccination platform.
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We conducted real-time bioimaging of the hyaluronate-interferon α (HA-IFNα) conjugate using a biologically inert zwitterionic fluorophore of ZW800-1 for the treatment of hepatitis C virus (HCV) infection. ZW800-1 was labeled on the IFNα molecule of the HA-IFNα conjugate to investigate its biodistribution and clearance without altering its physicochemical and targeting characteristics. Confocal microscopy clearly visualized the effective in vitro cellular uptake of the HA-IFNα conjugate to HepG2 cells. After verifying the biological activity in Daudi cells, we conducted the pharmacokinetic analysis of the HA-IFNα conjugate, which confirmed its target-specific delivery to the liver with a prolonged residence time longer than that of PEGylated IFNα. In vivo and ex vivo bioimaging of the ZW800-1-labeled HA-IFNα conjugate directly showed real-time biodistribution and clearance of the conjugate that are consistent with the biological behaviors analyzed by an enzyme-linked immunosorbent assay. Furthermore, the elevated level of OAS1 mRNA in the liver confirmed in vivo antiviral activity of HA-IFNα conjugates. With the data taken together, we could confirm the feasibility of ZW800-1 as a biologically inert fluorophore and target-specific HA-IFNα conjugate for the treatment of HCV infection.
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Hepacivirus , Hepatite C , Ácido Hialurônico , Interferon-alfa , Compostos de Amônio Quaternário , Ácidos Sulfônicos , Células Hep G2 , Hepatite C/tratamento farmacológico , Hepatite C/patologia , Humanos , Ácido Hialurônico/química , Ácido Hialurônico/farmacologia , Interferon-alfa/química , Interferon-alfa/farmacologia , Microscopia de Fluorescência , Compostos de Amônio Quaternário/química , Compostos de Amônio Quaternário/farmacologia , Ácidos Sulfônicos/química , Ácidos Sulfônicos/farmacologiaRESUMO
Promoter hypermethylation of the O(6)-methylguanine-DNA methyltransferase (MGMT) DNA repair gene is important during carcinogenesis. We explored whether organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs), were associated with hypermethylation of the MGMT gene promoter in peripheral leukocytes among 368 Koreans without cancer. Hypermethylation decreased as OCPs increased (Ptrend = 0.02), while PCB concentrations showed an inverted U-shaped association (Pquadratic < 0.01). The prevalence of MGMT promoter hypermethylation was highest within the 2nd quintile of the PCB summary score (28.4%), while it was only 2.7% in the upper 10% score. Chronic exposure to these chemicals may affect methylation of the MGMT promoter, with possibly non-monotonic dose response relationships.
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Metilação de DNA , Hidrocarbonetos Clorados/sangue , Praguicidas/sangue , Bifenilos Policlorados/sangue , Estudos de Casos e Controles , Poluentes Ambientais/sangue , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Modelos Logísticos , Pessoa de Meia-Idade , O(6)-Metilguanina-DNA Metiltransferase/genética , Reação em Cadeia da Polimerase , Regiões Promotoras Genéticas/genética , Inquéritos e QuestionáriosRESUMO
BACKGROUND: We investigated if certain persistent organic pollutants (POPs), namely polychlorinated biphenyls (PCBs) and organochlorine (OC) pesticides, predicted total, cardiovascular disease (CVD), and cancer mortality among the elderly, with the hypothesis that associations differ by the amount of fat mass. METHODS: We studied serum concentrations of 11 PCBs in 633 elders (age≥70 years) and of 5 OC pesticides in 675 elders within the National Health and Nutrition Examination Survey (NHANES) 1999-2004. Mean follow-up was 4.1-years. RESULTS: Neither PCBs nor OC pesticides were associated with total mortality when fat mass was not considered in analyses. However, associations of PCBs and OC pesticides with total mortality depended on fat mass (Pinteraction<0.01 and 0.06, respectively). PCBs associated inversely with total mortality for high fat mass, but not for lower fat mass. On the contrary, OC pesticides associated positively with total mortality for low fat mass and this association weakened at higher fat mass. The interaction was also observed with CVD mortality. In elders with low fat mass, higher PCBs associated with 2-3 fold higher risk of CVD mortality, while this association was absent in elders with more fat mass (Pinteraction=0.03). The positive association between OC pesticides and CVD mortality was also observed only among elderly with low fat mass (Pinteraction=0.03). CONCLUSIONS: The possibility of interaction between POPs and the amount of fat mass on risk of mortality from chronic diseases is clinically important in modern societies with an obesity epidemic and requires confirmation in other studies with larger sample size.
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Doenças Cardiovasculares/mortalidade , Exposição Ambiental , Hidrocarbonetos Clorados/sangue , Neoplasias/mortalidade , Praguicidas/sangue , Bifenilos Policlorados/sangue , Absorciometria de Fóton , Adiposidade , Idoso , Idoso de 80 Anos ou mais , Doenças Cardiovasculares/induzido quimicamente , Poluentes Ambientais/sangue , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Masculino , Neoplasias/induzido quimicamente , Inquéritos Nutricionais , Modelos de Riscos Proporcionais , Estados Unidos/epidemiologiaRESUMO
BACKGROUND: Despite the consistent relationship between serum γ-glutamyltransferase (GGT) and type 2 diabetes (T2D), one unsolved issue is the role of serum GGT in the well-known association between obesity and T2D. This study was performed to investigate whether the association between body mass index (BMI) and impaired fasting glucose (IFG) differed depending on serum GGT levels within the normal range. METHODS: Study subjects were 2,424 men and 3,652 women aged ≥ 40, participating in the Fifth Korean National Health and Nutrition Examination Survey. Serum GGT levels within the normal range were classified into gender-specific tertiles. RESULTS: Among men and women belonging to the lowest tertile of serum GGT, BMI showed statistically non-significant weak associations with the risk of IFG. However, among persons in the highest tertile of serum GGT, the risk of IFG was 3 - 4 times higher among persons with BMI ≥ 25 kg/m2 than those with BMI < 23 kg/m2 (Pinteraction = 0.032 in men and 0.059 in women). CONCLUSIONS: The well-known strong association between BMI and IFG was observed mainly among persons with elevation of serum GGT to certain physiological levels, suggesting a critical role of serum GGT in the pathogenesis of IFG. This finding has an important clinical implication because serum GGT can be used to detect high-risk obese persons.
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Diabetes Mellitus Tipo 2/sangue , Intolerância à Glucose/sangue , Obesidade/complicações , gama-Glutamiltransferase/sangue , Glicemia/análise , Índice de Massa Corporal , Estudos Transversais , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/etiologia , Feminino , Seguimentos , Intolerância à Glucose/diagnóstico , Intolerância à Glucose/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos Nutricionais , Obesidade/fisiopatologia , Prognóstico , Valores de Referência , Fatores de RiscoRESUMO
Advances in nano/micro technologies in recent years have significantly improved biosensors in terms of their viability for biomedical purposes, from diagnostic to therapeutic applications, allowing for effective early detection and personalized treatment modalities [...].
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Técnicas Biossensoriais , Nanotecnologia , TecnologiaRESUMO
Carbon nanotubes (CNTs) have been regarded as emerging materials in various applications. However, the range of biomedical applications is limited due to the aggregation and potential toxicity of powder-type CNTs. To overcome these issues, techniques to assemble them into various macroscopic structures, such as one-dimensional fibers, two-dimensional films, and three-dimensional aerogels, have been developed. Among them, carbon nanotube fiber (CNTF) is a one-dimensional aggregate of CNTs, which can be used to solve the potential toxicity problem of individual CNTs. Furthermore, since it has unique properties due to the one-dimensional nature of CNTs, CNTF has beneficial potential for biomedical applications. This review summarizes the biomedical applications using CNTF, such as the detection of biomolecules or signals for biosensors, strain sensors for wearable healthcare devices, and tissue engineering for regenerating human tissues. In addition, by considering the challenges and perspectives of CNTF for biomedical applications, the feasibility of CNTF in biomedical applications is discussed.
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Técnicas Biossensoriais , Nanotubos de Carbono , Dispositivos Eletrônicos Vestíveis , Humanos , Nanotubos de Carbono/química , Fator Neurotrófico Ciliar , Engenharia Tecidual/métodos , Técnicas Biossensoriais/métodosRESUMO
Cryotherapy leverages controlled freezing temperature interventions to engender a cascade of tumor-suppressing effects. However, its bottleneck lies in the standalone ineffectiveness. A promising strategy is using nanoparticle therapeutics to augment the efficacy of cryotherapy. Here, a cold-responsive nanoplatform composed of upconversion nanoparticles coated with silica - chlorin e6 - hyaluronic acid (UCNPs@SiO2-Ce6-HA) is designed. This nanoplatform is employed to integrate cryotherapy with photodynamic therapy (PDT) in order to improve skin cancer treatment efficacy in a synergistic manner. The cryotherapy appeared to enhance the upconversion brightness by suppressing the thermal quenching. The low-temperature treatment afforded a 2.45-fold enhancement in the luminescence of UCNPs and a 3.15-fold increase in the photodynamic efficacy of UCNPs@SiO2-Ce6-HA nanoplatforms. Ex vivo tests with porcine skins and the subsequent validation in mouse tumor tissues revealed the effective HA-mediated transdermal delivery of designed nanoplatforms to deep tumor tissues. After transdermal delivery, in vivo photodynamic therapy using the UCNPs@SiO2-Ce6-HA nanoplatforms resulted in the optimized efficacy of 79% in combination with cryotherapy. These findings underscore the Cryo-PDT as a truly promising integrated treatment paradigm and warrant further exploring the synergistic interplay between cryotherapy and PDT with bright upconversion to unlock their full potential in cancer therapy.
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Ácido Hialurônico , Nanopartículas , Fotoquimioterapia , Animais , Fotoquimioterapia/métodos , Camundongos , Ácido Hialurônico/química , Nanopartículas/química , Neoplasias Cutâneas/terapia , Neoplasias Cutâneas/tratamento farmacológico , Crioterapia/métodos , Clorofilídeos , Porfirinas/química , Porfirinas/administração & dosagem , Modelos Animais de Doenças , Fármacos Fotossensibilizantes/administração & dosagem , Administração Cutânea , Dióxido de Silício/química , SuínosRESUMO
Early and accurate detection of colorectal cancer (CRC) is critical for improving patient outcomes. Existing diagnostic techniques are often invasive and carry risks of complications. Herein, we introduce a plasmonic gold nanopolyhedron (AuNH)-coated needle-based surface-enhanced Raman scattering (SERS) sensor, integrated with endoscopy, for direct mucus sampling and label-free detection of CRC. The thin and flexible stainless-steel needle is coated with polymerized dopamine, which serves as an adhesive layer and simultaneously initiates the nucleation of gold nanoparticle (AuNP) seeds on the needle surface. The AuNP seeds are further grown through a surface-directed reduction using Au ions-hydroxylamine hydrochloride solution, resulting in the formation of dense AuNHs. The formation mechanism of AuNHs and the layered structure of the plasmonic needle-based SERS (PNS) sensor are thoroughly analyzed. Furthermore, a strong field enhancement of the PNS sensor is observed, amplified around the edges of the polyhedral shapes and at nanogap sites between AuNHs. The feasibility of the PNS sensor combined with endoscopy system is further investigated using mouse models for direct colonic mucus sampling and verifying noninvasive label-free classification of CRC from normal controls. A logistic regression-based machine learning method is employed and successfully differentiates CRC and normal mice, achieving 100% sensitivity, 93.33% specificity, and 96.67% accuracy. Moreover, Raman profiling of metabolites and their correlations with Raman signals of mucus samples are analyzed using the Pearson correlation coefficient, offering insights for identifying potential cancer biomarkers. The developed PNS-assisted endoscopy technology is expected to advance the early screening and diagnosis approach of CRC in the future.
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Fulvic acids (FAs) have been commercially used in cosmetics and agronomy due to their unique biological activities, such as plant stimulation and anti-inflammatory effects. However, the extraction sources of FAs, such as peat, are currently limited. Consequently, new extraction methods using renewable resources need to be developed, while reproducing the biological functions. Here, ionic liquids (ILs) effectively extracted fulvic-like substances (FLSs) from wood sawdust. The overall molecular weight distributions of FLSs were similar to those of commercial FAs, and key organic groups (e.g., aromatic, phenolic, and methoxy groups) were also found to be shared between commercial FAs and FLSs. Detailed compositional analysis revealed by high-resolution mass spectrometry showed that the extracts contain both lignin-like and lipid-like molecules, while commercial FAs are biased toward lignin-like and carbohydrate-like molecules. FLSs generally showed better and similar performance in radical scavenging activity against ABTS+· and H2O2. Fibroblast proliferation and lettuce growth enhancements were also observed with the extract containing 1-ethyl-3-methylimidazolium acetate and triethylammonium hydrogen sulfate, respectively, which performed better than commercial FAs. Immunofluorescence staining of in vitro human follicle dermal papilla cells supports that coexpression of hair growth-related proteins can be accelerated with FLSs, and this effect was further evidenced by in vivo mouse model experiments. Finally, the reusability of ILs in the extraction process was confirmed by analyzing the structural features of FLSs from each recycling. Our findings indicate that ILs are useful for obtaining biologically functional fulvic analogs from renewable plant sources.
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Over the past two decades, lanthanide-based upconversion nanoparticles (UCNPs) have been fascinating scientists due to their ability to offer unprecedented prospects to upconvert tissue-penetrating near-infrared light into color-tailorable optical illumination inside biological matter. In particular, luminescent behavior UCNPs have been widely utilized for background-free biorecognition and biosensing. Currently, a paramount challenge exists on how to maximize NIR light harvesting and upconversion efficiencies for achieving faster response and better sensitivity without damaging the biological tissue upon laser assisted photoactivation. In this review, we offer the reader an overview of the recent updates about exciting achievements and challenges in the development of plasmon-modulated upconversion nanoformulations for biosensing application.
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Técnicas Biossensoriais , Elementos da Série dos Lantanídeos , Nanopartículas , LuminescênciaRESUMO
Cancer is a disease caused by abnormal cell growth that spreads through other parts of the body and threatens life by destroying healthy tissues. Therefore, numerous techniques have been employed not only to diagnose and monitor the progress of cancer in a precise manner but also to develop appropriate therapeutic agents with enhanced efficacy and safety profiles. In this regard, molecularly imprinted polymers (MIPs), synthetic receptors that recognize targeted molecules with high affinity and selectivity, have been intensively investigated as one of the most attractive biomaterials for theragnostic approaches. This review describes diverse synthesis strategies to provide the rationale behind these synthetic antibodies and provides a selective overview of the recent progress in the in vitro and in vivo targeting of cancer biomarkers for diagnosis and therapeutic applications. Taken together, the topics discussed in this review provide concise guidelines for the development of novel MIP-based systems to diagnose cancer more precisely and promote successful treatment. Molecularly imprinted polymers (MIPs), synthetic receptors that recognize targeted molecules with high affinity and selectivity, have been intensively investigated as one of the most attractive biomaterials for cancer theragnostic approaches. This review describes diverse synthesis strategies to provide the rationale behind these synthetic antibodies and provides a selective overview of the recent progress in the in vitro and in vivo targeting of cancer biomarkers for diagnosis and therapeutic applications. The topics discussed in this review aim to provide concise guidelines for the development of novel MIP-based systems to diagnose cancer more precisely and promote successful treatment.
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Macromolecules are large, complex molecules composed of smaller subunits known as monomers. The four primary categories of macromolecules found in living organisms are carbohydrates, lipids, proteins, and nucleic acids; they also encompass a broad range of natural and synthetic polymers. Recent studies have shown that biologically active macromolecules can help regenerate hair, providing a potential solution for current hair regeneration therapies. This review examines the latest developments in the use of macromolecules for the treatment of hair loss. The fundamental principles of hair follicle (HF) morphogenesis, hair shaft (HS) development, hair cycle regulation, and alopecia have been introduced. Microneedle (MN) and nanoparticle (NP) delivery systems are innovative treatments for hair loss. Additionally, the application of macromolecule-based tissue-engineered scaffolds for the in vitro and in vivo neogenesis of HFs is discussed. Furthermore, a new research direction is explored wherein artificial skin platforms are adopted as a promising screening method for hair loss treatment drugs. Through these multifaceted approaches, promising aspects of macromolecules for future hair loss treatments are identified.
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Metal-doped carbon dots have attracted considerable attention in nanomedicine over the last decade owing to their high biocompatibility and great potential for bioimaging, photothermal therapy, and photodynamic therapy. In this study, we prepared, and for the first time, examined terbium-doped CDs (Tb-CDs) as a novel contrast agent for computed tomography. A detailed physicochemical analysis revealed that the prepared Tb-CDs have small sizes (â¼2-3 nm), contain relatively high terbium concentration (â¼13.3 wt%), and exhibit excellent aqueous colloidal stability. Furthermore, preliminary cell viability and CT measurements suggested that Tb-CDs exhibit negligible cytotoxicity toward L-929 cells and demonstrate high X-ray absorption performance (â¼48.2 ± 3.9 HU L g-1). Based on these findings, the prepared Tb-CDs could serve as a promising contrast agent for efficient X-ray attenuation.