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1.
Nat Commun ; 15(1): 4235, 2024 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-38762489

RESUMO

Inflammation induced by lung infection is a double-edged sword, moderating both anti-viral and immune pathogenesis effects; the mechanism of the latter is not fully understood. Previous studies suggest the vasculature is involved in tissue injury. Here, we report that expression of Sparcl1, a secreted matricellular protein, is upregulated in pulmonary capillary endothelial cells (EC) during influenza-induced lung injury. Endothelial overexpression of SPARCL1 promotes detrimental lung inflammation, with SPARCL1 inducing 'M1-like' macrophages and related pro-inflammatory cytokines, while SPARCL1 deletion alleviates these effects. Mechanistically, SPARCL1 functions through TLR4 on macrophages in vitro, while TLR4 inhibition in vivo ameliorates excessive inflammation caused by endothelial Sparcl1 overexpression. Finally, SPARCL1 expression is increased in lung ECs from COVID-19 patients when compared with healthy donors, while fatal COVID-19 correlates with higher circulating SPARCL1 protein levels in the plasma. Our results thus implicate SPARCL1 as a potential prognosis biomarker for deadly COVID-19 pneumonia and as a therapeutic target for taming hyperinflammation in pneumonia.


Assuntos
COVID-19 , Células Endoteliais , Pulmão , Ativação de Macrófagos , SARS-CoV-2 , Animais , Humanos , COVID-19/imunologia , COVID-19/virologia , COVID-19/metabolismo , COVID-19/patologia , Camundongos , Células Endoteliais/metabolismo , Células Endoteliais/virologia , Células Endoteliais/imunologia , SARS-CoV-2/fisiologia , Pulmão/virologia , Pulmão/patologia , Pulmão/imunologia , Receptor 4 Toll-Like/metabolismo , Receptor 4 Toll-Like/genética , Proteínas de Ligação ao Cálcio/metabolismo , Proteínas de Ligação ao Cálcio/genética , Camundongos Endogâmicos C57BL , Pneumonia Viral/imunologia , Pneumonia Viral/patologia , Pneumonia Viral/virologia , Pneumonia Viral/metabolismo , Masculino , Macrófagos/metabolismo , Macrófagos/imunologia , Feminino , Camundongos Knockout , Proteínas da Matriz Extracelular
2.
Biomaterials ; 308: 122545, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38547831

RESUMO

Macrophages are key modulators of all inflammatory diseases and essential for their resolution, making macrophage cell therapy a promising strategy for regenerative medicine. However, since macrophages change rapidly in response to microenvironmental cues, their phenotype must be controlled post-administration. We present a tunable biomaterial-based strategy to control macrophages intracellularly via small molecule-releasing microparticles. Poly(lactic-co-glycolic acid) microparticles encapsulating the anti-inflammatory and anti-fibrotic drug dexamethasone were administered to macrophages in vitro, with uptake rates controlled by different loading regimes. Microparticle dose and dexamethasone content directly affected macrophage phenotype and phagocytic capacity, independent of particle content per cell, leading to an overall pro-reparative, anti-inflammatory, anti-fibrotic phenotype with increased phagocytic and ECM degrading functionality. Intracellularly controlled macrophages partially maintained this phenotype in vivo in a murine pulmonary fibrosis model, with more prominent effects in a pro-fibrotic environment compared to pro-inflammatory. These results suggest that intracellular control using biomaterials has the potential to control macrophage phenotype post-administration, which is essential for successful macrophage cell therapy.


Assuntos
Materiais Biocompatíveis , Dexametasona , Macrófagos , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Animais , Macrófagos/metabolismo , Macrófagos/efeitos dos fármacos , Materiais Biocompatíveis/química , Dexametasona/farmacologia , Dexametasona/uso terapêutico , Camundongos , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Terapia Baseada em Transplante de Células e Tecidos/métodos , Camundongos Endogâmicos C57BL , Inflamação/patologia , Fibrose Pulmonar/terapia , Fibrose Pulmonar/patologia , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Fagocitose/efeitos dos fármacos , Células RAW 264.7 , Ácido Poliglicólico/química , Ácido Láctico/química , Fibrose
3.
Sci Transl Med ; 16(732): eadg6229, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38295183

RESUMO

Disruption of pulmonary vascular homeostasis is a central feature of viral pneumonia, wherein endothelial cell (EC) death and subsequent angiogenic responses are critical determinants of the outcome of severe lung injury. A more granular understanding of the fundamental mechanisms driving reconstitution of lung endothelium is necessary to facilitate therapeutic vascular repair. Here, we demonstrated that TGF-ß signaling through TGF-ßR2 (transforming growth factor-ß receptor 2) is activated in pulmonary ECs upon influenza infection, and mice deficient in endothelial Tgfbr2 exhibited prolonged injury and diminished vascular repair. Loss of endothelial Tgfbr2 prevented autocrine Vegfa (vascular endothelial growth factor α) expression, reduced endothelial proliferation, and impaired renewal of aerocytes thought to be critical for alveolar gas exchange. Angiogenic responses through TGF-ßR2 were attributable to leucine-rich α-2-glycoprotein 1, a proangiogenic factor that counterbalances canonical angiostatic TGF-ß signaling. Further, we developed a lipid nanoparticle that targets the pulmonary endothelium, Lung-LNP (LuLNP). Delivery of Vegfa mRNA, a critical TGF-ßR2 downstream effector, by LuLNPs improved the impaired regeneration phenotype of EC Tgfbr2 deficiency during influenza injury. These studies defined a role for TGF-ßR2 in lung endothelial repair and demonstrated efficacy of an efficient and safe endothelial-targeted LNP capable of delivering therapeutic mRNA cargo for vascular repair in influenza infection.


Assuntos
Influenza Humana , Humanos , Camundongos , Animais , Receptor do Fator de Crescimento Transformador beta Tipo II , Fator A de Crescimento do Endotélio Vascular , Pulmão/metabolismo , Fator de Crescimento Transformador beta/metabolismo , RNA Mensageiro
5.
Eur Urol ; 84(4): 393-405, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37169638

RESUMO

CONTEXT: Differences in recovery, oncological, and quality of life (QoL) outcomes between open radical cystectomy (ORC) and robot-assisted radical cystectomy (RARC) for patients with bladder cancer are unclear. OBJECTIVE: This review aims to compare these outcomes within randomized trials of ORC and RARC in this context. The primary outcome was the rate of 90-d perioperative events. The secondary outcomes included operative, pathological, survival, and health-related QoL (HRQoL) measures. EVIDENCE ACQUISITION: Systematic literature searches of MEDLINE, Embase, Web of Science, and clinicaltrials.gov were performed up to May 31, 2022. EVIDENCE SYNTHESIS: Eight trials, reporting 1024 participants, were included. RARC was associated with a shorter hospital length of stay (LOS; mean difference [MD] 0.21, 95% confidence interval [CI] 0.03-0.39, p = 0.02) than and similar complication rates to ORC. ORC was associated with higher thromboembolic events (odds ratio [OR] 1.84, 95% CI 1.02-3.31, p = 0.04). ORC was associated with more blood loss (MD 322 ml, 95% CI 193-450, p < 0.001) and transfusions (OR 2.35, 95% CI 1.65-3.36, p < 0.001), but shorter operative time (MD 76 min, 95% CI 39-112, p < 0.001) than RARC. No differences in lymph node yield (MD 1.07, 95% CI -1.73 to 3.86, p = 0.5) or positive surgical margin rates (OR 0.95, 95% CI 0.54-1.67, p = 0.9) were present. RARC was associated with better physical functioning or well-being (standardized MD 0.47, 95% CI 0.29-0.65, p < 0.001) and role functioning (MD 8.8, 95% CI 2.4-15.1, p = 0.007), but no improvement in overall HRQoL. No differences in progression-free survival or overall survival were seen. Limitations may include a lack of generalization given trial patients. CONCLUSIONS: RARC offers various perioperative benefits over ORC. It may be more suitable in patients wishing to avoid blood transfusion, those wanting a shorter LOS, or those at a high risk of thromboembolic events. PATIENT SUMMARY: This study compares robot-assisted keyhole surgery with open surgery for bladder cancer. The robot-assisted approach offered less blood loss, shorter hospital stays, and fewer blood clots. No other differences were seen.


Assuntos
Procedimentos Cirúrgicos Robóticos , Robótica , Neoplasias da Bexiga Urinária , Humanos , Cistectomia/efeitos adversos , Qualidade de Vida , Resultado do Tratamento , Complicações Pós-Operatórias/etiologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Neoplasias da Bexiga Urinária/patologia , Procedimentos Cirúrgicos Robóticos/efeitos adversos
6.
Cell Rep ; 41(11): 111805, 2022 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-36516758

RESUMO

The lung exhibits a robust, multifaceted regenerative response to severe injuries such as influenza infection, during which quiescent lung-resident epithelial progenitors participate in two distinct reparative pathways: functionally beneficial regeneration via alveolar type 2 (AT2) cell proliferation and differentiation, and dysplastic tissue remodeling via intrapulmonary airway-resident basal p63+ progenitors. Here we show that the basal cell transcription factor ΔNp63 is required for intrapulmonary basal progenitors to participate in dysplastic alveolar remodeling following injury. We find that ΔNp63 restricts the plasticity of intrapulmonary basal progenitors by maintaining either active or repressive histone modifications at key differentiation gene loci. Following loss of ΔNp63, intrapulmonary basal progenitors are capable of either airway or alveolar differentiation depending on their surrounding environment both in vitro and in vivo. Uncovering these regulatory mechanisms of dysplastic repair and lung basal cell fate choice highlight potential therapeutic targets to promote functional alveolar regeneration following severe lung injuries.


Assuntos
Influenza Humana , Lesão Pulmonar , Humanos , Células Epiteliais Alveolares/metabolismo , Pulmão/metabolismo , Diferenciação Celular , Influenza Humana/metabolismo , Células Epiteliais/metabolismo
7.
Korean J Anesthesiol ; 75(1): 47-60, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34619855

RESUMO

BACKGROUND: Diabetes is a risk factor for postoperative complications. Previous meta-analyses have shown that elevated glycated hemoglobin (HbA1c) levels are associated with postoperative complications in various surgical populations. However, this is the first meta-analysis to investigate the association between preoperative HbA1c levels and postoperative complications in patients undergoing elective major abdominal surgery. METHODS: PRISMA guidelines were adhered to for this study. Six databases were searched up to April 1, 2020. Primary studies investigating the effect of HbA1c levels on postoperative complications after elective major abdominal surgery were included. Risk of bias and quality of evidence assessments were performed. Data were pooled using a random effects model. Meta-regression was performed to evaluate different HbA1c cut-off values. RESULTS: Twelve observational studies (25,036 patients) were included. Most studies received a 'good' and 'moderate quality' score using the NOS and GRADE, respectively. Patients with a high HbA1c had a greater risk of anastomotic leaks (odds ratio [OR]: 2.80, 95% CI [1.63, 4.83], P < 0.001), wound infections (OR: 1.21, 95% CI [1.08, 1.36], P = 0.001), major complications defined as Clavien-Dindo [CD] 3-5 (OR: 2.16, 95% CI [1.54, 3.01], P < 0.001), and overall complications defined as CD 1-5 (OR: 2.12, 95% CI [1.48, 3.04], P < 0.001). CONCLUSIONS: An HbA1c between 6% and 7% is associated with higher risks of anastomotic leaks, wound infections, major complications, and overall postoperative complications. Therefore, guidelines with an HbA1c threshold > 7% may be putting pre-optimized patients at risk. Future randomized controlled trials are needed to explore causation before policy changes are made.


Assuntos
Diabetes Mellitus , Procedimentos Cirúrgicos Eletivos , Abdome/cirurgia , Diabetes Mellitus/epidemiologia , Procedimentos Cirúrgicos Eletivos/efeitos adversos , Hemoglobinas Glicadas/análise , Humanos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia
8.
J Vasc Surg Venous Lymphat Disord ; 9(2): 510-524.e4, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33227458

RESUMO

OBJECTIVE: Absorbable inferior vena cava filters (IVCFs) could be more effective and safer than standard IVCFs in theory, as they will self-resorb over time, thus rendering the need for filter retrieval and the risks associated with it unnecessary. This scoping review aims to evaluate the design of current absorbable IVCFs, review the development phase of the absorbable IVCFs, assess the efficacy of the absorbable IVCFs and their complications, and discuss the limitations and areas for future research. METHODS: MEDLINE, PubMed, and Embase databases were electronically searched and citations of relevant studies manually searched. Study selection and data extraction were performed by two independent reviewers using predetermined criteria and stored on premade proforma, respectively. The risk of bias (RoB) for both in vitro and in vivo studies were performed using established RoB tools. RESULTS: Eight studies were suitable for inclusion in this scoping review; five were in vivo and three were in vitro studies. No clinical trials were found. The RoB varied from moderate to high for in vivo studies and from low to moderate for in vitro studies. Overall, there was evidence from both in vivo and in vitro studies that absorbable IVCFs were effective in clot capturing and self-resorption and could decrease complications associated with standard IVCFs. However, there was a broad lack of statistical analyses and control groups to determine the significance of these findings. CONCLUSIONS: Absorbable IVCFs have shown promising features and results in preclinical models. However, significant research needs to be further performed to achieve the ideal characteristics of an absorbable IVCF before the first human trial can be conducted safely.


Assuntos
Implantes Absorvíveis , Implantação de Prótese/instrumentação , Filtros de Veia Cava , Tromboembolia Venosa/prevenção & controle , Implantes Absorvíveis/efeitos adversos , Animais , Humanos , Desenho de Prótese , Implantação de Prótese/efeitos adversos , Fatores de Risco , Fatores de Tempo , Filtros de Veia Cava/efeitos adversos
9.
BMJ Open ; 10(9): e039422, 2020 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-32998928

RESUMO

INTRODUCTION: Diabetes has an increasing worldwide prevalence. It is known to be a predisposing factor for postoperative complications. Preoperative glycaemic control strategies should be pursued as glycaemic control could serve as a modifiable risk factor. Glycated haemoglobin (HbA1c), a marker of 3-month average glycaemic control, has been shown in meta-analyses to predict postoperative complications in cardiothoracic, bariatric and orthopaedic surgery. However, there is no meta-analysis in the major abdominal surgery population, in whom morbidity may be higher due to the nature of the surgery. Understanding the association between HbA1c and postoperative complications could help in preoperative risk prognostication, counselling and glycaemic target selection. The aim of this systematic review and meta-analysis is to evaluate all evidence on the association between preoperative HbA1c and postoperative complications in elective major abdominal surgery, and to investigate the threshold HbA1c level before postoperative complication rates increase. METHODS AND ANALYSIS: This review will be performed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses Protocols guidelines. PubMed, Embase, Cochrane Central Register of Controlled Trials, Google Scholar and China National Knowledge Infrastructure will be searched for all original studies. Study selection, data extraction, risk of bias and quality assessment will be conducted by two independent reviewers. The primary outcome is the association between preoperative HbA1c and major postoperative complications (Clavien Dindo 3-5), and the secondary outcome is the association between HbA1c and overall postoperative complications. Data management and synthesis will be performed using Microsoft Excel and Stata to derive pool estimates. ETHICS AND DISSEMINATION: No ethics approval is required as only secondary data will be used. Findings will be disseminated through peer-reviewed journals and conference presentations. PROSPERO REGISTRATION NUMBER: CRD42020167347.


Assuntos
Glicemia , Procedimentos Cirúrgicos Eletivos , China , Hemoglobinas Glicadas , Humanos , Metanálise como Assunto , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Revisões Sistemáticas como Assunto
10.
J Vasc Surg Venous Lymphat Disord ; 8(2): 182-186, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31327742

RESUMO

BACKGROUND: Post-thrombotic syndrome is a common complication of iliofemoral deep venous thrombosis (IFDVT). Existing evidence and National Institute for Health and Care Excellence guidelines suggest that this can be reduced by prompt thrombolytic therapy or thrombectomy. We aimed to evaluate the characteristics of IFDVT patients and to identify whether patients are being offered the recommended treatment pathway. METHODS: A multicenter cross-sectional study was conducted across eight hospital sites in the North West London region, of which two were hub hospitals in their local vascular service networks. Patients with proximal DVT were identified using International Classification of Diseases, Tenth Revision coding during a 1-year period. Data on demographics, diagnostic methods used, interventions, and referrals were extracted from electronic and paper medical records. RESULTS: During the study period, 132 patients with IFDVT were identified (mean age, 59.4 years; 55% female); 75% of these patients had an IFDVT. In this cohort, the biggest predisposing factors were previous DVT (n = 35), malignant disease (n = 35), and immobility (n = 20). In total, 104 patients were administered anticoagulation, and 88 of these patients received anticoagulation within 24 hours. The cases of 45 patients were either discussed with or promptly referred to a vascular service, after which 20 patients were treated solely with anticoagulation, whereas 20 patients received thrombolysis of varying methods. CONCLUSIONS: A significant proportion (56%) of symptomatic IFDVT patients are not being appropriately referred to or discussed with vascular services. Of these, 43% would have been eligible for consideration of early thrombus removal. Adherence to the National Institute for Health and Care Excellence guidelines could be improved by increasing awareness among emergency department colleagues.


Assuntos
Anticoagulantes/uso terapêutico , Veia Femoral , Veia Ilíaca , Padrões de Prática Médica , Encaminhamento e Consulta , Terapia Trombolítica , Trombose Venosa/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticoagulantes/efeitos adversos , Estudos Transversais , Feminino , Veia Femoral/diagnóstico por imagem , Fidelidade a Diretrizes , Humanos , Veia Ilíaca/diagnóstico por imagem , Londres , Masculino , Pessoa de Meia-Idade , Síndrome Pós-Trombótica/etiologia , Síndrome Pós-Trombótica/prevenção & controle , Guias de Prática Clínica como Assunto , Terapia Trombolítica/efeitos adversos , Fatores de Tempo , Resultado do Tratamento , Trombose Venosa/complicações , Trombose Venosa/diagnóstico por imagem
11.
Curr Stem Cell Res Ther ; 14(7): 532-548, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30973112

RESUMO

The potential use of stem cell-based therapies for the repair and regeneration of various tissues and organs offers a paradigm shift in regenerative medicine. The use of either embryonic stem cells (ESC) or induced pluripotent stem cells (iPSC) in clinical situations is limited because of regulations and ethical considerations even though these cells are theoretically highly beneficial. While clinically, adipose-derived stem cells (ADSCs) are one of the most widely used types of stem cells used more than five years in clinically setting. It has many advantages including; yields a high number of ADSCs per volume of tissue, high rate of proliferation, anti-fibrotic, anti-apoptotic, anti-inflammation, immunomodulation, and paracrine mechanisms have been demonstrated in various preclinical studies. It is much easier to harvest compared with bone marrow stem cells. Results of clinical studies have demonstrated the potentials of ADSCs for stem cells therapy for a number of clinical disorders. The aim of this paper was to provide an update on the most recent developments of ADSCs, by highlighting the properties and features of ADSCs, critically discussing its clinical benefit and its clinical trials in treatment and regeneration. This is a multi-billion dollars industry with huge interest to clinician, academia and industries.


Assuntos
Tecido Adiposo/citologia , Medicina Regenerativa , Transplante de Células-Tronco/métodos , Células-Tronco/citologia , Engenharia Tecidual/métodos , Animais , Diferenciação Celular , Humanos
12.
Trends Biotechnol ; 36(5): 477-480, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29500003

RESUMO

3D models are emerging as valuable tools for personalised nanoparticle-based cancer treatments. 3D models represent in vivo cancers more realistically than 2D patterns that are grown in Petri dishes. However, creating a 3D cancer model that mimics the complexity and heterogeneity of cancers in vivo remains difficult.


Assuntos
Nanopartículas , Neoplasias , Terapia Genética , Humanos
13.
Trends Biotechnol ; 35(12): 1124-1125, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28822599

RESUMO

Organic nanoparticle-based (ONP) gene therapy is a potential strategy to cure human cancer. However, there are still many practical barriers before the promising results from in vitro and preclinical studies can be translated to clinical success. We discuss the reasons behind the hesitant uptake by the clinic.


Assuntos
Terapia Genética/métodos , Nanopartículas , Neoplasias/terapia , Pesquisa Translacional Biomédica , Ensaios Clínicos como Assunto , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Técnicas de Transferência de Genes , Heterogeneidade Genética , Humanos , Sensibilidade e Especificidade , Resultado do Tratamento
14.
J Clin Rheumatol ; 23(5): 273-277, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28700529

RESUMO

BACKGROUND: Among patients with rheumatoid arthritis (RA), smoking increases risk of severe RA and pulmonary and cardiovascular disease. Despite this, little is known about smoking cessation counseling by rheumatologists. OBJECTIVES: We examined predictors of tobacco counseling in RA patients who smoke including the effect of perceived RA control. We hypothesized that patients with controlled RA would receive more counseling according to the competing demands model, which explains that preventive care gaps occur as a result of competing provider, patient, and clinic factors. METHODS: This secondary data analysis involved RA patients with an additional cardiovascular disease risk factor identified in an academic medical center 2004-2011. Trained abstractors assessed documented smoking counseling and rheumatologists' impression of RA control in clinic notes. We used multivariable logistic regression to predict having received smoking cessation counseling, including sociodemographics and comorbidity in models. RESULTS: We abstracted 3396 RA visits, including 360 visits (10%) with active smokers. Perceived controlled RA was present in 31% of visits involving smokers (39% in nonsmokers). Beyond nurse documentation, providers documented smoking status in 39% of visit notes with smokers and smoking cessation counseling in 10%. Visits with controlled versus active RA were less likely to include counseling (odds ratio, 0.3; confidence interval, 0.1-0.97). Counseling was more likely in visits with prevalent cardiovascular, pulmonary, and psychiatric disease, but decreased with obesity. CONCLUSIONS: Smoking cessation counseling was documented in 10% of visits and was less likely when RA was controlled. Given smoking's impact on RA and long-term outcomes, systematic cessation counseling efforts are needed.


Assuntos
Artrite Reumatoide , Doenças Cardiovasculares , Aconselhamento Diretivo/métodos , Pneumopatias , Abandono do Hábito de Fumar , Fumar , Adulto , Artrite Reumatoide/complicações , Artrite Reumatoide/diagnóstico , Artrite Reumatoide/psicologia , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Feminino , Humanos , Pneumopatias/epidemiologia , Pneumopatias/etiologia , Masculino , Pessoa de Meia-Idade , Avaliação das Necessidades , Medicina Preventiva/métodos , Melhoria de Qualidade , Reumatologistas/normas , Fatores de Risco , Fumar/efeitos adversos , Fumar/epidemiologia , Abandono do Hábito de Fumar/métodos , Abandono do Hábito de Fumar/psicologia , Estados Unidos/epidemiologia
15.
Curr Pharm Des ; 23(20): 2908-2917, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28215155

RESUMO

BACKGROUND: The study of magnetic nanoparticles (MNPs) for drug delivery has recently seen a surge of interest even though the first studies were conducted as early as in the seventies. Despite this, there are still gaps in the knowledge of the field, implicating the complexities in designing the ideal MNP for drug delivery. The large surface area of MNPs and the ability to manipulate with an externally applied magnetic field render the MNP a good candidate for targeted delivery of drugs. Drugs are conjugated to the surface of MNPs or encapsulated within, while the surface of MNPs receives a protective coating and is functionalised with ligands, enzymes, linkers, and active molecules to deliver the drug to a targeted site. RESULTS: These MNPs in the form of nanogels, micelles, polymers, dendrimers, and receptor-targeted have been studied in vitro and in vivo to assess morphology, cytotoxicity, localisation and others, which are the indicators of efficacy. While preclinical studies appear to be promising, there is a limited translation from bench to bedside for reasons such as inconsistent results between similar studies and inadequate profiles of toxicity, drug release and biodistribution amongst many others. However, the substantial number of clinical trials of MNPs in other applications such as hyperthermia for the treatment of cancer and imaging shows that there is indeed potential in the development of MNPs to achieve successful drug delivery. CONCLUSION: The lack of optimal design for MNP surface functionalization and conjugation to drug and other molecules for delivery to target cells gives plenty of room for the research and development of the ideal MNP, which is indicated for the future of MNPs in biomedical applications.


Assuntos
Sistemas de Liberação de Medicamentos , Nanopartículas de Magnetita/química , Preparações Farmacêuticas/administração & dosagem , Humanos , Preparações Farmacêuticas/química , Projetos de Pesquisa
16.
Trends Biotechnol ; 35(5): 434-451, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28108036

RESUMO

The high mortality rates of cancer patients receiving standard treatments emphasize the crucial need for alternative treatments. One promising strategy is to use organic nanoparticles (NPs) for gene delivery. Although multifunctional NPs theoretically have many desirable properties as gene vectors, there are several practical barriers to successful gene delivery. In this review we discuss the properties of NPs and overview in vitro and preclinical studies of organic NPs over the past 5 years. The results of recent clinical trials suggest that the NP field holds significant promise. The annual market value for successful gene delivery could exceed US$30 billion, and this will encourage researchers to study the application of NPs to therapeutic gene delivery.


Assuntos
DNA/genética , Terapia Genética/tendências , Nanocápsulas/química , Nanotecnologia/tendências , Neoplasias/genética , Neoplasias/terapia , Transfecção/tendências , Animais , DNA/administração & dosagem , Humanos , Nanocápsulas/administração & dosagem , Nanocápsulas/ultraestrutura , Neoplasias/patologia , Resultado do Tratamento
17.
Rheumatology (Oxford) ; 54(8): 1415-9, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25731768

RESUMO

OBJECTIVE: RA increases vascular disease and angiogenesis, yet a 1964 Lancet report paradoxically linked RA to lower diabetic retinopathy. Our objective was to examine RA as a risk factor for diabetic retinopathy compared with other vascular risk factors. METHODS: This cohort study compared the prevalence of diabetic retinopathy in diabetes patients with and without RA in a 5% Medicare sample. We analysed the impact of RA on the prevalence of diabetic retinopathy using multivariate logistic regression calculating adjusted rate ratios (ARRs) controlling for sociodemographics, co-morbidity and health utilization. Sensitivity analysis examined eye exam rates. RESULTS: Among 256 331 Medicare diabetes patients, 5572 (2%) had RA. Diabetic retinopathy was less prevalent in patients with RA compared with those without RA (13.7% vs 16.1%, P ≤ 0.01). Compared with patients without RA, the adjusted model demonstrated that patients with diabetes and RA were 28% less likely to have diabetic retinopathy and 4% more likely to receive an eye exam [ARR 0.72 (95% CI 0.67, 0.77), ARR 1.04 (95% CI 1.02, 1.06)]. CONCLUSION: Findings support the 1964 paradox observing decreased diabetic retinopathy in patients with RA. These findings pose new questions regarding whether RA physiology or treatments protect against diabetic retinopathy and how intraocular factors vary in contrast to adverse vascular changes elsewhere.


Assuntos
Artrite Reumatoide/complicações , Artrite Reumatoide/fisiopatologia , Retinopatia Diabética/epidemiologia , Retinopatia Diabética/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Antirreumáticos/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Estudos de Coortes , Retinopatia Diabética/prevenção & controle , Feminino , Humanos , Modelos Logísticos , Masculino , Medicare/estatística & dados numéricos , Prevalência , Estudos Retrospectivos , Fatores de Risco , Estados Unidos
18.
Acta Neuropathol Commun ; 2: 15, 2014 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-24502382

RESUMO

Multiple system atrophy (MSA) is a progressive neurodegenerative disease characterized by the accumulation of α-synuclein protein in the cytoplasm of oligodendrocytes, the myelin-producing support cells of the central nervous system (CNS). The brain is the most lipid-rich organ in the body and disordered metabolism of various lipid constituents is increasingly recognized as an important factor in the pathogenesis of several neurodegenerative diseases. α-Synuclein is a 17 kDa protein with a close association to lipid membranes and biosynthetic processes in the CNS, yet its precise function is a matter of speculation, particularly in oligodendrocytes. α-Synuclein aggregation in neurons is a well-characterized feature of Parkinson's disease and dementia with Lewy bodies. Epidemiological evidence and in vitro studies of α-synuclein molecular dynamics suggest that disordered lipid homeostasis may play a role in the pathogenesis of α-synuclein aggregation. However, MSA is distinct from other α-synucleinopathies in a number of respects, not least the disparate cellular focus of α-synuclein pathology. The recent identification of causal mutations and polymorphisms in COQ2, a gene encoding a biosynthetic enzyme for the production of the lipid-soluble electron carrier coenzyme Q10 (ubiquinone), puts membrane transporters as central to MSA pathogenesis, although how such transporters are involved in the early myelin degeneration observed in MSA remains unclear. The purpose of this review is to bring together available evidence to explore the potential role of membrane transporters and lipid dyshomeostasis in the pathogenesis of α-synuclein aggregation in MSA. We hypothesize that dysregulation of the specialized lipid metabolism involved in myelin synthesis and maintenance by oligodendrocytes underlies the unique neuropathology of MSA.


Assuntos
Encéfalo/metabolismo , Transtornos do Metabolismo dos Lipídeos/etiologia , Atrofia de Múltiplos Sistemas/complicações , Atrofia de Múltiplos Sistemas/patologia , Alquil e Aril Transferases/genética , Encéfalo/patologia , Humanos , Atrofia de Múltiplos Sistemas/genética , Mutação/genética
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