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1.
Int J Mol Sci ; 24(21)2023 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-37958705

RESUMO

Trace elements and metals play critical roles in the normal functioning of the central nervous system (CNS), and their dysregulation has been implicated in neurodegenerative disorders such as Alzheimer's disease (AD) and Parkinson's disease (PD). In a healthy CNS, zinc, copper, iron, and manganese play vital roles as enzyme cofactors, supporting neurotransmission, cellular metabolism, and antioxidant defense. Imbalances in these trace elements can lead to oxidative stress, protein aggregation, and mitochondrial dysfunction, thereby contributing to neurodegeneration. In AD, copper and zinc imbalances are associated with amyloid-beta and tau pathology, impacting cognitive function. PD involves the disruption of iron and manganese levels, leading to oxidative damage and neuronal loss. Toxic metals, like lead and cadmium, impair synaptic transmission and exacerbate neuroinflammation, impacting CNS health. The role of aluminum in AD neurofibrillary tangle formation has also been noted. Understanding the roles of these elements in CNS health and disease might offer potential therapeutic targets for neurodegenerative disorders. The Codex Alimentarius standards concerning the mentioned metals in foods may be one of the key legal contributions to safeguarding public health. Further research is needed to fully comprehend these complex mechanisms and develop effective interventions.


Assuntos
Doença de Alzheimer , Doenças Neurodegenerativas , Doença de Parkinson , Oligoelementos , Humanos , Cobre/uso terapêutico , Doença de Alzheimer/patologia , Manganês/uso terapêutico , Oligoelementos/uso terapêutico , Zinco/uso terapêutico , Ferro/uso terapêutico , Metais/uso terapêutico , Doenças Neurodegenerativas/patologia
2.
Curr Pharm Des ; 29(30): 2377-2386, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37859328

RESUMO

The neurodegenerative disorders are age-related illnesses that cause the morphology or activity of neurons to deteriorate over time. Alzheimer's disease is the most frequent neurodegenerative illness in the long run. The rate of advancement might vary, even though it is a progressive neurological illness. Various explanations have been proposed, however the true etiology of Alzheimer's disease remains unclear. Most pharmacological interventions are based on the cholinergic theory, that is earliest idea. In accordance with the amyloid hypothesis, the buildup of beta-amyloid in brain regions is the primitive cause of illness. There is no proof that any one strategy is useful in avoiding Alzheimer's disease, though some epidemiological studies have suggested links within various modifiable variables, such as cardiovascular risk, diet and so on. Different metals like zinc, iron, and copper are naturally present in our bodies. In metal chelation therapy drugs are used to jam the metal ions from combining with other molecules in the body. Clioquinol is one of the metal chelation drugs used by researchers. Research on metal chelation is still ongoing. In the present review, we go over the latest developments in prevalence, incidence, etiology, or pathophysiology of our understanding of Alzheimer's disease. Additionally, a brief discussion on the development of therapeutic chelating agents and their viability as Alzheimer's disease medication candidates is presented. We also assess the effect of clioquinol as a potential metal chelator.


Assuntos
Doença de Alzheimer , Clioquinol , Humanos , Doença de Alzheimer/tratamento farmacológico , Clioquinol/farmacologia , Clioquinol/uso terapêutico , Metais/uso terapêutico , Quelantes/uso terapêutico , Quelantes/farmacologia , Peptídeos beta-Amiloides , Cobre
3.
J Nanobiotechnology ; 21(1): 399, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37904235

RESUMO

BACKGROUNDS: The novel concept of microwave dynamic therapy (MDT) solves the problem of incomplete tumor eradication caused by non-selective heating and uneven temperature distribution of microwave thermal therapy (MWTT) in clinic, but the poor delivery of microwave sensitizer and the obstacle of tumor hypoxic microenvironment limit the effectiveness of MDT. RESULTS: Herein, we engineer a liquid metal-based nanozyme LM@ZIF@HA (LZH) with eutectic Gallium Indium (EGaIn) as the core, which is coated with CoNi-bimetallic zeolite imidazole framework (ZIF) and hyaluronic acid (HA). The flexibility of the liquid metal and the targeting of HA enable the nanozyme to be effectively endocytosed by tumor cells, solving the problem of poor delivery of microwave sensitizers. Due to the catalase-like activity, the nanozyme catalyze excess H2O2 in the tumor microenvironment to generate O2, alleviating the restriction of the tumor hypoxic microenvironment and promoting the production of ROS under microwave irradiation. In vitro cell experiments, the nanozyme has remarkable targeting effect, oxygen production capacity, and microwave dynamic effect, which effectively solves the defects of MDT. In the constructed patient-derived xenograft (PDX) model, the nanozyme achieves excellent MDT effect, despite the heterogeneity and complexity of the tumor model that is similar to the histological and pathological features of the patient. The tumor volume in the LZH + MW group is only about 1/20 of that in the control group, and the tumor inhibition rate is as high as 95%. CONCLUSION: The synthesized nanozyme effectively solves the defects of MDT, improves the targeted delivery of microwave sensitizers while regulating the hypoxic microenvironment of tumors, and achieves excellent MDT effect in the constructed PDX model, providing a new strategy for clinical cancer treatment.


Assuntos
Neoplasias da Mama , Neoplasias , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Micro-Ondas , Peróxido de Hidrogênio , Neoplasias/tratamento farmacológico , Metais/uso terapêutico , Linhagem Celular Tumoral , Microambiente Tumoral
4.
Nat Rev Chem ; 7(3): 202-224, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-37117903

RESUMO

Bacteria, similar to most organisms, have a love-hate relationship with metals: a specific metal may be essential for survival yet toxic in certain forms and concentrations. Metal ions have a long history of antimicrobial activity and have received increasing attention in recent years owing to the rise of antimicrobial resistance. The search for antibacterial agents now encompasses metal ions, nanoparticles and metal complexes with antimicrobial activity ('metalloantibiotics'). Although yet to be advanced to the clinic, metalloantibiotics are a vast and underexplored group of compounds that could lead to a much-needed new class of antibiotics. This Review summarizes recent developments in this growing field, focusing on advances in the development of metalloantibiotics, in particular, those for which the mechanism of action has been investigated. We also provide an overview of alternative uses of metal complexes to combat bacterial infections, including antimicrobial photodynamic therapy and radionuclide diagnosis of bacterial infections.


Assuntos
Anti-Infecciosos , Infecções Bacterianas , Complexos de Coordenação , Humanos , Antibacterianos/farmacologia , Complexos de Coordenação/farmacologia , Farmacorresistência Bacteriana , Anti-Infecciosos/farmacologia , Metais/uso terapêutico , Infecções Bacterianas/tratamento farmacológico , Íons/farmacologia
5.
J Nanobiotechnology ; 21(1): 20, 2023 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-36658649

RESUMO

The slightest change in the extra/intracellular concentration of metal ions results in amplified effects by signaling cascades that regulate both cell fate within the tumor microenvironment and immune status, which influences the network of antitumor immunity through various pathways. Based on the fact that metal ions influence the fate of cancer cells and participate in both innate and adaptive immunity, they are widely applied in antitumor therapy as immune modulators. Moreover, nanomedicine possesses the advantage of precise delivery and responsive release, which can perfectly remedy the drawbacks of metal ions, such as low target selectivity and systematic toxicity, thus providing an ideal platform for metal ion application in cancer treatment. Emerging evidence has shown that immunotherapy applied with nanometallic materials may significantly enhance therapeutic efficacy. Here, we focus on the physiopathology of metal ions in tumorigenesis and discuss several breakthroughs regarding the use of nanometallic materials in antitumor immunotherapeutics. These findings demonstrate the prominence of metal ion-based nanomedicine in cancer therapy and prophylaxis, providing many new ideas for basic immunity research and clinical application. Consequently, we provide innovative insights into the comprehensive understanding of the application of metal ions combined with nanomedicine in cancer immunotherapy in the past few years.


Assuntos
Neoplasias , Humanos , Neoplasias/tratamento farmacológico , Metais/uso terapêutico , Imunoterapia/métodos , Transdução de Sinais , Íons , Nanomedicina/métodos , Microambiente Tumoral
6.
J Inorg Biochem ; 239: 112086, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36495657

RESUMO

Alzheimer's disease (AD), the most common form of neurodegeneration disorder in adults, is becoming the overwhelming burden on the healthcare and economic system. In this study, chrysin derivative with the morpholine moiety was designed, synthesized and evaluated based on the multi targets directed ligands strategy for the treatment of AD centered with therapeutic attempts to restore metal homeostasis. It selectively coordinated with the important bio-metal ions related AD, especially Cu2+. Notably, single crystals of both 1 and 1-Cu(II) were obtained and the single crystal structures were characterized by X-ray crystal diffraction, which provided a basis to further explore the possible structure-activity relationship at the molecular level. Compound 1 and 1-Cu(II) complex showed potent anti-oxidative activities, with respect to both ·OH and ·O2- scavenging properties In addition, 1 had good inhibitory activity on Aß1-42 aggregation, and it could target copper dyshomeostasis through extracting Cu2+ from the amyloids. The studies in silico showed that 1 had brain availability and peroral bioavailability. Taken together, compound 1, as the derivative of chrysin, might be a promising advanced lead candidate for the development of new anti-AD drugs and it may provide a useful template for studying the structure-activity relationships of biometal-coordinating drugs.


Assuntos
Doença de Alzheimer , Humanos , Ligantes , Doença de Alzheimer/tratamento farmacológico , Flavonoides/farmacologia , Flavonoides/uso terapêutico , Metais/uso terapêutico , Cobre/química , Peptídeos beta-Amiloides , Estrutura Molecular
7.
J Nanobiotechnology ; 20(1): 457, 2022 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-36274142

RESUMO

Due to the urgent demand for more anti-cancer methods, the new applications of metal ions in cancer have attracted increasing attention. Especially the three kinds of the new mode of cell death, including ferroptosis, calcicoptosis, and cuproptosis, are of great concern. Meanwhile, many metal ions have been found to induce cell death through different approaches, such as interfering with osmotic pressure, triggering biocatalysis, activating immune pathways, and generating the prooxidant effect. Therefore, varieties of new strategies based on the above approaches have been studied and applied for anti-cancer applications. Moreover, many contrast agents based on metal ions have gradually become the core components of the bioimaging technologies, such as MRI, CT, and fluorescence imaging, which exhibit guiding significance for cancer diagnosis. Besides, the new nano-theranostic platforms based on metal ions have experimentally shown efficient response to endogenous and exogenous stimuli, which realizes simultaneous cancer therapy and diagnosis through a more controlled nano-system. However, most metal-based agents have still been in the early stages, and controlled clinical trials are necessary to confirm or not the current expectations. This article will focus on these new explorations based on metal ions, hoping to provide some theoretical support for more anti-cancer ideas.


Assuntos
Meios de Contraste , Neoplasias , Humanos , Íons , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Metais/uso terapêutico
8.
Genes (Basel) ; 12(10)2021 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-34680871

RESUMO

Controlling spread of resistance genes from wastewater to aquatic systems requires more knowledge on how resistance genes are acquired and transmitted. Whole genomic sequences from sewage-associated staphylococcus isolates (20 S. aureus, 2 Staphylococcus warneri, and 2 Staphylococcus delphini) were analyzed for the presence of antibiotic resistance genes (ARGs) and metal resistance genes (MRGs). Plasmid sequences were identified in each isolate to investigate co-carriage of ARGs and MRGs within. BLASTN analysis showed that 67% of the isolates carried more than one ARG. The carriage of multiple plasmids was observed more in CC5 than CC8 S. aureus strains. Plasmid exchange was observed in all staphylococcus species except the two S. delphini isolates that carried multiple MRGs, no ARGs, and no plasmids. 85% of S. aureus isolates carried the blaZ gene, 76% co-carried blaZ with cadD and cadX, with 62% of these isolates carrying blaZ, cadD, and cadX on the same plasmid. The co-carriage of ARGs and MRGs in S. warneri isolates, and carriage of MRGs in S. delphini, without plasmids suggests non-conjugative transmission routes for gene acquisition. More studies are required that focus on the transduction and transformation routes of transmission to prevent interspecies exchange of ARGs and MRGs in sewage-associated systems.


Assuntos
Proteínas de Bactérias/genética , Farmacorresistência Bacteriana/genética , Transferência Genética Horizontal/genética , Proteínas de Membrana/genética , Infecções Estafilocócicas/genética , Staphylococcus aureus/genética , Antibacterianos/efeitos adversos , Antibacterianos/uso terapêutico , Genoma Bacteriano/genética , Humanos , Metais/efeitos adversos , Metais/uso terapêutico , Plasmídeos/genética , Esgotos/microbiologia , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/microbiologia , Staphylococcus/efeitos dos fármacos , Staphylococcus/genética , Staphylococcus aureus/patogenicidade , Sequenciamento Completo do Genoma
9.
Naunyn Schmiedebergs Arch Pharmacol ; 394(10): 1991-2002, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34415355

RESUMO

The current understanding of osteoarthritis is developing from a mechanical disease caused by cartilage wear to a complex biological response involving inflammation, oxidative stress and other aspects. Nanoparticles are widely used in drug delivery due to its good stability in vivo and cell uptake efficiency. In addition to the above advantages, metal/metal oxide NPs, such as cerium oxide and manganese dioxide, can also simulate the activity of antioxidant enzymes and catalyze the degradation of superoxide anions and hydrogen peroxide. Degrading of metal/metal oxide nanoparticles releases metal ions, which may slow down the progression of osteoarthritis by inhibiting inflammation, promoting cartilage repair and inhibiting cartilage ossification. In present review, we focused on recent research works concerning osteoarthritis treating with metal/metal oxide nanoparticles, and introduced some potential nanoparticles that may have therapeutic effects.


Assuntos
Nanopartículas Metálicas/uso terapêutico , Metais/uso terapêutico , Osteoartrite/tratamento farmacológico , Óxidos/uso terapêutico , Animais , Cartilagem/metabolismo , Humanos , Metais/farmacocinética , Osteoartrite/metabolismo , Óxidos/farmacocinética
10.
Nutrients ; 13(6)2021 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-34071548

RESUMO

The levels of many essential minerals decrease during pregnancy if un-supplemented, including calcium, iron, magnesium, selenium, zinc, and possibly chromium and iodine. Sub-optimal intake of minerals from preconception through pregnancy increases the risk of many pregnancy complications and infant health problems. In the U.S., dietary intake of minerals is often below the Recommended Dietary Allowance (RDA), especially for iodine and magnesium, and 28% of women develop iron deficiency anemia during their third trimester. The goal of this paper is to propose evidence-based recommendations for the optimal level of prenatal supplementation for each mineral for most women in the United States. Overall, the evidence suggests that optimal mineral supplementation can significantly reduce a wide range of pregnancy complications (including anemia, gestational hypertension, gestational diabetes, hyperthyroidism, miscarriage, and pre-eclampsia) and infant health problems (including anemia, asthma/wheeze, autism, cerebral palsy, hypothyroidism, intellectual disability, low birth weight, neural tube defects, preterm birth, rickets, and wheeze). An evaluation of 180 commercial prenatal supplements found that they varied widely in mineral content, often contained only a subset of essential minerals, and the levels were often below our recommendations. Therefore, there is a need to establish recommendations on the optimal level of mineral supplementation during pregnancy.


Assuntos
Suplementos Nutricionais , Metais , Minerais , Cuidado Pré-Natal , Adulto , Medicina Baseada em Evidências , Feminino , Humanos , Metais/administração & dosagem , Metais/uso terapêutico , Minerais/administração & dosagem , Minerais/uso terapêutico , Gravidez , Complicações na Gravidez/tratamento farmacológico , Complicações na Gravidez/prevenção & controle , Estados Unidos , Adulto Jovem
11.
PLoS One ; 16(5): e0251885, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34003868

RESUMO

It is widely recognized that innate macrophage immune reactions to implant debris are central to the inflammatory responses that drive biologic implant failure over the long term. Less common, adaptive lymphocyte immune reactions to implant debris, such as delayed type hypersensitivity (DTH), can also affect implant performance. It is unknown which key patient factors, if any, mediate these adaptive immune responses that potentiate particle/macrophage mediated osteolysis. The objective of this investigation was to determine to what degree known adaptive immune responses to metal implant debris can affect particle-induced osteolysis (PIO); and if this pathomechanism is dependent on: 1) innate immune danger signaling, i.e., NLRP3 inflammasome activity, 2) sex, and/or 3) age. We used an established murine calvaria model of PIO using male and female wild-type C57BL/6 vs. Caspase-1 deficient mice as well as young (12-16 weeks old) vs. aged (18-24 months old) female and male C57BL/6 mice. After induction of metal-DTH, and Cobalt-alloy particle (ASTM F-75, 0.4um median diameter) calvaria challenge, bone resorption was assessed using quantitative micro-computed tomography (micro-CT) analysis and immune responses were assessed by measuring paw inflammation, lymphocyte transformation test (LTT) reactivity and adaptive immune cytokines IFN-gamma and IL-17 (ELISA). Younger aged C57BL/6 female mice exhibited the highest rate and severity of metal sensitivity lymphocyte responses that also translated into higher PIO compared to any other experimental group. The absence of inflammasome/caspase-1 activity significantly suppressed DTH metal-reactivity and osteolysis in both male and female Caspase-1 deficient mice. These murine model results indicate that young female mice are more predisposed to metal-DTH augmented inflammatory responses to wear debris, which is highly influenced by active NLRP3 inflammasome/caspase-1 danger signaling. If these results are clinically meaningful for orthopedic patients, then younger female individuals should be appropriately assessed and followed for DTH derived peri-implant complications.


Assuntos
Caspase 1/genética , Metais/efeitos adversos , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Osteólise/genética , Próteses e Implantes/efeitos adversos , Fatores Etários , Animais , Reabsorção Óssea/etiologia , Reabsorção Óssea/genética , Reabsorção Óssea/patologia , Feminino , Humanos , Hipersensibilidade/etiologia , Hipersensibilidade/genética , Hipersensibilidade/fisiopatologia , Imunidade Inata/efeitos dos fármacos , Imunidade Inata/genética , Inflamassomos/efeitos dos fármacos , Inflamassomos/genética , Interferon gama/genética , Interleucina-17/genética , Macrófagos/efeitos dos fármacos , Masculino , Metais/uso terapêutico , Camundongos , Osteólise/induzido quimicamente , Osteólise/patologia , Caracteres Sexuais , Crânio/efeitos dos fármacos , Crânio/crescimento & desenvolvimento , Crânio/fisiopatologia , Microtomografia por Raio-X
12.
J Cell Physiol ; 236(10): 7144-7158, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33694161

RESUMO

Transition metals refer to the elements in the d and ds blocks of the periodic table. Since the success of cisplatin and auranofin, transition metal-based compounds have become a prospective source for drug development, particularly in cancer treatment. In recent years, extensive studies have shown that numerous transition metal-based compounds could modulate autophagy, promising a new therapeutic strategy for metal-related diseases and the design of metal-based agents. Copper, zinc, and manganese, which are common components in physiological pathways, play important roles in the progression of cancer, neurodegenerative diseases, and cardiovascular diseases. Furthermore, enrichment of copper, zinc, or manganese can regulate autophagy. Thus, we summarized the current advances in elucidating the mechanisms of some metals/metal-based compounds and their functions in autophagy regulation, which is conducive to explore the intricate roles of autophagy and exploit novel therapeutic drugs for human diseases.


Assuntos
Autofagia/efeitos dos fármacos , Doenças Cardiovasculares/tratamento farmacológico , Complexos de Coordenação/uso terapêutico , Metais/uso terapêutico , Neoplasias/tratamento farmacológico , Doenças Neurodegenerativas/tratamento farmacológico , Elementos de Transição/uso terapêutico , Animais , Doenças Cardiovasculares/metabolismo , Doenças Cardiovasculares/patologia , Complexos de Coordenação/metabolismo , Humanos , Metais/metabolismo , Neoplasias/metabolismo , Neoplasias/patologia , Doenças Neurodegenerativas/metabolismo , Doenças Neurodegenerativas/patologia , Elementos de Transição/metabolismo
13.
J Nanobiotechnology ; 19(1): 26, 2021 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-33468160

RESUMO

With the rapid advancement and progress of nanotechnology, nanomaterials with enzyme-like catalytic activity have fascinated the remarkable attention of researchers, due to their low cost, high operational stability, adjustable catalytic activity, and ease of recycling and reuse. Nanozymes can catalyze the same reactions as performed by enzymes in nature. In contrast the intrinsic shortcomings of natural enzymes such as high manufacturing cost, low operational stability, production complexity, harsh catalytic conditions and difficulties of recycling, did not limit their wide applications. The broad interest in enzymatic nanomaterial relies on their outstanding properties such as stability, high activity, and rigidity to harsh environments, long-term storage and easy preparation, which make them a convenient substitute instead of the native enzyme. These abilities make the nanozymes suitable for multiple applications in sensing and imaging, tissue engineering, environmental protection, satisfactory tumor diagnostic and therapeutic, because of distinguished properties compared with other artificial enzymes such as high biocompatibility, low toxicity, size dependent catalytic activities, large surface area for further bioconjugation or modification and also smart response to external stimuli. This review summarizes and highlights latest progress in applications of metal and metal oxide nanomaterials with enzyme/multienzyme mimicking activities. We cover the applications of sensing, cancer therapy, water treatment and anti-bacterial efficacy. We also put forward the current challenges and prospects in this research area, hoping to extension of this emerging field. In addition to therapeutic potential of nanozymes for disease prevention, their practical effects in diagnostics, to monitor the presence of SARS-CoV-2 and related biomarkers for future pandemics will be predicted.


Assuntos
Materiais Biomiméticos/química , Metais/química , Nanomedicina/métodos , Nanoestruturas/química , Óxidos/química , Animais , Antibacterianos/química , Antibacterianos/uso terapêutico , Biocatálise , Materiais Biomiméticos/uso terapêutico , Técnicas Biossensoriais/métodos , Biotecnologia/métodos , Teste para COVID-19/métodos , Monitoramento Ambiental/métodos , Humanos , Metais/uso terapêutico , Nanotecnologia/métodos , Neoplasias/diagnóstico , Neoplasias/terapia , Óxidos/uso terapêutico
14.
J Biomed Mater Res A ; 109(5): 666-681, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-32608184

RESUMO

The bone regenerative capacity of synthetic calcium phosphates (CaPs) can be enhanced through the enrichment with selected metal trace ions. However, defining the optimal elemental composition required for bone formation is challenging due to many possible concentrations and combinations of these elements. We hypothesized that the ideal elemental composition exists in the inorganic phase of the bone extracellular matrix (ECM). To study our hypothesis, we first obtained natural hydroxyapatite through the calcination of bovine bone, which was then investigated its reactivity with acidic phosphates to produce CaP cements. Bioceramic scaffolds fabricated using these cements were assessed for their composition, properties, and in vivo regenerative performance and compared with controls. We found that natural hydroxyapatite could react with phosphoric acid to produce CaP cements with biomimetic trace metals. These cements present significantly superior in vivo bone regenerative performance compared with cements prepared using synthetic apatite. In summary, this study opens new avenues for further advancements in the field of CaP bone biomaterials by introducing a simple approach to develop biomimetic CaPs. This work also sheds light on the role of the inorganic phase of bone and its composition in defining the regenerative properties of natural bone xenografts.


Assuntos
Biomimética , Regeneração Óssea/efeitos dos fármacos , Fosfatos de Cálcio/farmacologia , Cerâmica/farmacologia , Metais/farmacologia , Oligoelementos/farmacologia , Animais , Cimentos Ósseos/química , Fosfatos de Cálcio/química , Bovinos , Ácido Cítrico/farmacologia , Força Compressiva , Cristalografia por Raios X , Durapatita/química , Durapatita/isolamento & purificação , Feminino , Teste de Materiais , Metais/análise , Metais/uso terapêutico , Ácidos Fosfóricos/farmacologia , Ratos , Ratos Sprague-Dawley , Espectroscopia de Infravermelho com Transformada de Fourier , Tíbia/diagnóstico por imagem , Tíbia/efeitos dos fármacos , Tíbia/lesões , Oligoelementos/análise , Oligoelementos/uso terapêutico , Microtomografia por Raio-X
15.
Int J Mol Sci ; 22(1)2020 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-33375478

RESUMO

An aging population leads to increasing demand for sustained quality of life with the aid of novel implants. Patients expect fast healing and few complications after surgery. Increased biofunctionality and antimicrobial behavior of implants, in combination with supportive stem cell therapy, can meet these expectations. Recent research in the field of bone implants and the implementation of autologous mesenchymal stem cells in the treatment of bone defects is outlined and evaluated in this review. The article highlights several advantages, limitations and advances for metal-, ceramic- and polymer-based implants and discusses the future need for high-throughput screening systems used in the evaluation of novel developed materials and stem cell therapies. Automated cell culture systems, microarray assays or microfluidic devices are required to efficiently analyze the increasing number of new materials and stem cell-assisted therapies. Approaches described in the literature to improve biocompatibility, biofunctionality and stem cell differentiation efficiencies of implants range from the design of drug-laden nanoparticles to chemical modification and the selection of materials that mimic the natural tissue. Combining suitable implants with mesenchymal stem cell treatment promises to shorten healing time and increase treatment success. Most research studies focus on creating antibacterial materials or modifying implants with antibacterial coatings in order to address the increasing number of complications after surgeries that are mostly caused by bacterial infections. Moreover, treatment of multiresistant pathogens will pose even bigger challenges in hospitals in the future, according to the World Health Organization (WHO). These antibacterial materials will help to reduce infections after surgery and the number of antibiotic treatments that contribute to the emergence of new multiresistant pathogens, whilst the antibacterial implants will help reduce the amount of antibiotics used in clinical treatment.


Assuntos
Regeneração Óssea , Ensaios de Triagem em Larga Escala/métodos , Células-Tronco Mesenquimais/citologia , Transplante de Células-Tronco/métodos , Engenharia Tecidual/métodos , Tecidos Suporte/química , Cicatrização , Animais , Antibacterianos/química , Antibacterianos/uso terapêutico , Regeneração Óssea/fisiologia , Técnicas de Cultura de Células/métodos , Cerâmica/química , Cerâmica/uso terapêutico , Ensaios de Triagem em Larga Escala/instrumentação , Humanos , Metais/química , Metais/uso terapêutico , Osteogênese/efeitos dos fármacos , Osteogênese/fisiologia , Polímeros/química , Polímeros/uso terapêutico , Tecidos Suporte/microbiologia , Cicatrização/efeitos dos fármacos , Cicatrização/fisiologia
16.
Bone Joint J ; 102-B(8): 1025-1032, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32731836

RESUMO

AIMS: Total knee arthroplasty is an established treatment for knee osteoarthritis with excellent long-term results, but there remains controversy about the role of uncemented prostheses. We present the long-term results of a randomized trial comparing an uncemented tantalum metal tibial component with a conventional cemented component of the same implant design. METHODS: Patients under the age of 70 years with symptomatic osteoarthritis of the knee were randomized to receive either an uncemented tantalum metal tibial monoblock component or a standard cemented modular component. The mean age at time of recruitment to the study was 63 years (50 to 70), 46 (51.1%) knees were in male patients, and the mean body mass index was 30.4 kg/m2 (21 to 36). The same cruciate retaining total knee system was used in both groups. All patients received an uncemented femoral component and no patients had their patella resurfaced. Patient outcomes were assessed preoperatively and postoperatively using the modified Oxford Knee Score, Knee Society Score, and 12-Item Short-Form Health Survey questionnaire (SF-12) score. Radiographs were analyzed using the American Knee Society Radiograph Evaluation score. Operative complications, reoperations, or revision surgery were recorded. A total of 90 knees were randomized and at last review 77 knees were assessed. In all, 11 patients had died and two were lost to follow-up. RESULTS: At final review all patients were between 11 and 15 years following surgery. In total, 41 of the knees were cemented and 36 uncemented. There were no revisions in the cemented group and one revision in the uncemented group for fracture. The uncemented group reported better outcomes with both statistically and clinically significant (p = 0.001) improvements in knee-specific Oxford and Knee Society scores compared with the cemented group. The global SF-12 scores demonstrated no statistical difference (p = 0.812). Uncemented knees had better radiological analysis compared with the cemented group (p < 0.001). CONCLUSION: Use of an uncemented trabecular metal tibial implant can afford better long-term clinical outcomes when compared to cemented tibial components of a matched design. However, both have excellent survivorship up to 15 years after implantation. Cite this article: Bone Joint J 2020;102-B(8):1025-1032.


Assuntos
Artroplastia do Joelho/efeitos adversos , Artroplastia do Joelho/métodos , Cimentos Ósseos/farmacologia , Osteoartrite do Joelho/cirurgia , Desenho de Prótese/métodos , Falha de Prótese , Idoso , Feminino , Seguimentos , Humanos , Masculino , Metais/uso terapêutico , Pessoa de Meia-Idade , Osteoartrite do Joelho/diagnóstico por imagem , Reoperação/estatística & dados numéricos , Medição de Risco , Método Simples-Cego , Tantálio/uso terapêutico , Tíbia/cirurgia , Fatores de Tempo , Resultado do Tratamento
17.
Arch Orthop Trauma Surg ; 140(11): 1791-1808, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32715399

RESUMO

INTRODUCTION: Although metallosis is a well-known complication after total hip arthroplasty, little is known about this phenomenon after total (TKA) or unicompartmental knee arthroplasty (UKA). The aim of the present work was to review the current knowledge about the reasons and the diagnostic as well as therapeutic management of metallosis after knee arthroplasty. MATERIALS AND METHODS: A literature search was performed through PubMed until April 2019. Search terms were "metallosis" in combination with "knee", "knee prosthesis", "knee arthroplasty" and "knee replacement", respectively. All publications were analyzed regarding publication year, level of evidence, number of knees/patients treated, type of prosthesis, metallosis cause, time period between primary implantation and metallosis emergence, laboratory examination, treatment, complications and follow up. RESULTS: A total of 38 studies reporting on a total of 97 knees were identified. 29 studies reported on metallosis after TKA, 8 after UKA, and one study after both procedures. The time period between the primary implantation and metallosis emergence ranged between 6 weeks and 26 years. The most common reason was the failure of a metal-backed patellar component in 40%, followed by implant/structural- and PE failure (wear/dislocation) in 27% and 18% of the cases, respectively. Complete blood cell count, serum chemistry, erythrocyte sedimentation rate or C-reactive protein serum values were not indicative to diagnose metallosis. The diagnosis was confirmed by histopathological analyses and macroscopic evaluation during surgery. Depending on the particular cause various surgical procedures have been performed. Complete prosthesis exchange was the most common one showing no complications in 89.4% of the cases. CONCLUSIONS: Metallosis after knee arthroplasty is a rare and perhaps underestimated or under published complication. A systematic diagnostic approach is necessary for the timely and correct diagnosis. A thorough debridement as well as a (sub)total synovectomy should be always performed. In cases with a damaged component, a partial/complete prosthesis exchange leads to the best results. Should a malalignment be the cause of the metallosis, then it should be corrected within the revision surgery.


Assuntos
Artroplastia do Joelho , Metais , Complicações Pós-Operatórias , Artroplastia do Joelho/efeitos adversos , Artroplastia do Joelho/instrumentação , Humanos , Metais/efeitos adversos , Metais/uso terapêutico , Reoperação
18.
Acta Orthop ; 91(6): 682-686, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32619155

RESUMO

Background and purpose - The use of trabecular metal cups in primary total hip arthroplasty (THA) is increasing, despite the survival of Continuum cups being slightly inferior compared with other uncemented cups in registries. This difference is mainly explained by a higher rate of dislocation revisions. Cup malpositioning is a risk factor for dislocation and, being made of a highly porous material, Continuum cups might be more difficult to position. We evaluated whether Continuum cups had worse cup positioning compared with other uncemented cups. Patients and methods - Based on power calculation, 150 Continuum cups from 1 center were propensity score matched with 150 other uncemented cups from 4 centers. All patients had an uncemented stem, femoral head size of 32 mm or 36 mm, and BMI between 19 and 35. All operations were done for primary osteoarthrosis through a posterior approach. Patients were matched using age, sex, and BMI. Cup positioning was measured from anteroposterior pelvic radiograph using the Martell Hip Analysis Suite software. Results - There was no clinically relevant difference in mean inclination angle between the study group and the control group (43° [95% CI 41-44] and 43° [CI 42-45], respectively). The study group had a larger mean anteversion angle compared with the control group, 19° (CI 18-20) and 17° (CI 15-18) respectively. Interpretation - Continuum cups had a greater anteversion compared with the other uncemented cups. However, the median anteversion was acceptable in both groups and this difference does not explain the larger dislocation rate in the Continuum cups observed in earlier studies.


Assuntos
Artroplastia de Quadril , Anteversão Óssea , Prótese de Quadril/efeitos adversos , Metais/uso terapêutico , Complicações Pós-Operatórias , Desenho de Prótese , Titânio/uso terapêutico , Artroplastia de Quadril/efeitos adversos , Artroplastia de Quadril/instrumentação , Artroplastia de Quadril/métodos , Anteversão Óssea/diagnóstico por imagem , Anteversão Óssea/etiologia , Anteversão Óssea/prevenção & controle , Análise de Falha de Equipamento , Feminino , Finlândia/epidemiologia , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/prevenção & controle , Desenho de Prótese/efeitos adversos , Desenho de Prótese/métodos , Falha de Prótese/etiologia , Ajuste de Prótese/métodos , Radiografia/métodos , Suécia/epidemiologia
19.
PLoS One ; 15(6): e0233215, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32520937

RESUMO

OBJECTIVE: To evaluate the efficacy of noble-metal coated catheters in reducing catheter-associated urinary tract infections (CAUTI) in adult patients requiring short term catheterization. METHODS: An electronic literature search of PubMed, BioMed Central, Embase, Scopus, CENTRAL (Cochrane Central Register of Controlled Trials) and Google scholar was carried out from inception to 10th October 2019. Any prospective study or randomized controlled trial (RCT) on adult patients comparing noble-metal coated urinary catheters with any standard catheter and evaluating the incidence of CAUTI or bacteriuria was included. RESULTS: A total of 13 studies were included in the systematic review. 12 were RCTs and one was a prospective cross-over trial. Catheters employed in the study group were grouped into two sub-groups: Silver alloy coated or Noble metal alloy-coated (Gold, Silver, and Palladium) catheters. Bacteriuria was the most commonly studied outcome variable across trials. Meta-analysis indicated that silver alloy-coated catheters (RR 0.63, 95%CI 0.44-0.90, P = 0.01; I2 = 72%) and noble metal alloy catheters (RR 0.58, 95%CI 0.41-0.81, P = 0.001; I2 = 0%) significantly reduce the risk of bacteriuria. Sub-group analysis based on the duration of catheterization demonstrated that silver alloy catheters reduce the risk of bacteriuria with >1week of catheterization (RR 0.46, 95%CI 0.26-0.81, P = 0.007; I2 = 63%). Symptomatic CAUTI was evaluated only in four studies with variable results. The quality of the included studies was not high. CONCLUSIONS: Our review indicates that bacteriuria may be reduced with the use of noble metal-coated catheters during short-term catheterization of adults, however, the quality of evidence is not high. It is not clear if these catheters reduce the risk of symptomatic CAUTI. Further homogenous RCTs are needed to provide clarity.


Assuntos
Metais/uso terapêutico , Cateterismo Urinário/efeitos adversos , Cateterismo Urinário/métodos , Bacteriúria/complicações , Bacteriúria/etiologia , Infecções Relacionadas a Cateter/etiologia , Ouro , Humanos , Paládio , Prata , Cateteres Urinários/tendências , Infecções Urinárias/epidemiologia
20.
Cell Mol Biol (Noisy-le-grand) ; 66(4): 28-32, 2020 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-32583787

RESUMO

Metallo-drugs have gained a huge attention among scientific community in the couple years. These drugs types have become important compounds in cancer therapy, where, for instance, platinum complexes are being used against many tumors worldwide. Nonetheless, to p-cymene metallo-derivatives a promising anticancer potential has also been increasingly proposed. In this sense, the present review aims to provide an in-depth revision of p-cymene metallo-drugs possible mechanisms of anticancer action for upcoming pharmaceutical and biotechnological prospects. p-cymene metallo-derivatives have revealed very interesting anticancer activities in various test systems, including cancer cells, being thus worth of note to deepen knowledge through clinical trials on their upcoming use for cancer chemotherapy combination.


Assuntos
Antineoplásicos/farmacologia , Cimenos/farmacologia , Metais/farmacologia , Animais , Antineoplásicos/química , Antineoplásicos/uso terapêutico , Cimenos/química , Cimenos/uso terapêutico , Humanos , Metais/uso terapêutico , Neoplasias/tratamento farmacológico
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