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1.
J Surg Res ; 299: 290-297, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38788465

RESUMO

INTRODUCTION: More than 1.2 million pulmonary artery catheters (PACs) are used in cardiac patients per annum within the United States. However, it is contraindicated in traditional 1.5 and 3T magnetic resonance imaging (MRI) scans. We aimed to test preclinical and clinical safety of using this imaging modality given the potential utility of needing it in the clinical setting. METHODS: We conducted two phantom experiments to ensure that the electromagnetic field power deposition associated with bare and jacketed PACs was safe and within the acceptable limit established by the Food and Drug Administration. The primary end points were the safety and feasibility of performing Point-of-Care (POC) MRI without imaging-related adverse events. We performed a preclinical computational electromagnetic simulation and evaluated these findings in nine patients with PACs on veno-arterial extracorporeal membrane oxygenation. RESULTS: The phantom experiments showed that the baseline point specific absorption rate through the head averaged 0.4 W/kg. In both the bare and jacketed catheters, the highest net specific absorption rates were at the neck entry point and tip but were negligible and unlikely to cause any heat-related tissue or catheter damage. In nine patients (median age 66, interquartile range 42-72 y) with veno-arterial extracorporeal membrane oxygenation due to cardiogenic shock and PACs placed for close hemodynamic monitoring, POC MRI was safe and feasible with good diagnostic imaging quality. CONCLUSIONS: Adult ECMO patients with PACs can safely undergo point-of-care low-field (64 mT) brain MRI within a reasonable timeframe in an intensive care unit setting to assess for acute brain injury that might otherwise be missed with conventional head computed tomography.

2.
Diagnostics (Basel) ; 14(6)2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38535027

RESUMO

Early detection of acute brain injury (ABI) is critical to intensive care unit (ICU) patient management and intervention to decrease major complications. Head CT (HCT) is the standard of care for the assessment of ABI in ICU patients; however, it has limited sensitivity compared to MRI. We retrospectively compared the ability of ultra-low-field portable MR (ULF-pMR) and head HCT, acquired within 24 h of each other, to detect ABI in ICU patients supported on extracorporeal membrane oxygenation (ECMO). A total of 17 adult patients (median age 55 years; 47% male) were included in the analysis. Of the 17 patients assessed, ABI was not observed on either ULF-pMR or HCT in eight patients (47%). ABI was observed in the remaining nine patients with a total of 10 events (8 ischemic, 2 hemorrhagic). Of the eight ischemic events, ULF-pMR observed all eight, while HCT only observed four events. Regarding hemorrhagic stroke, ULF-pMR observed only one of them, while HCT observed both. ULF-pMR outperformed HCT for the detection of ABI, especially ischemic injury, and may offer diagnostic advantages for ICU patients. The lack of sensitivity to hemorrhage may improve with modification of the imaging acquisition program.

3.
Res Sq ; 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38313271

RESUMO

Purpose: Early detection of acute brain injury (ABI) is critical for improving survival for patients with extracorporeal membrane oxygenation (ECMO) support. We aimed to evaluate the safety of ultra-low-field portable MRI (ULF-pMRI) and the frequency and types of ABI observed during ECMO support. Methods: We conducted a multicenter prospective observational study (NCT05469139) at two academic tertiary centers (August 2022-November 2023). Primary outcomes were safety and validation of ULF-pMRI in ECMO, defined as exam completion without adverse events (AEs); secondary outcomes were ABI frequency and type. Results: ULF-pMRI was performed in 50 patients with 34 (68%) on venoarterial (VA)-ECMO (11 central; 23 peripheral) and 16 (32%) with venovenous (VV)-ECMO (9 single lumen; 7 double lumen). All patients were imaged successfully with ULF-pMRI, demonstrating discernible intracranial pathologies with good quality. AEs occurred in 3 (6%) patients (2 minor; 1 serious) without causing significant clinical issues.ABI was observed in ULF-pMRI scans for 22 patients (44%): ischemic stroke (36%), intracranial hemorrhage (6%), and hypoxic-ischemic brain injury (4%). Of 18 patients with both ULF-pMRI and head CT (HCT) within 24 hours, ABI was observed in 9 patients with 10 events: 8 ischemic (8 observed on ULF-oMRI, 4 on HCT) and 2 hemorrhagic (1 observed on ULF-pMRI, 2 on HCT). Conclusions: ULF-pMRI was shown to be safe and valid in ECMO patients across different ECMO cannulation strategies. The incidence of ABI was high, and ULF-pMRI may more sensitive to ischemic ABI than HCT. ULF-pMRI may benefit both clinical care and future studies of ECMO-associated ABI.

4.
Neurology ; 102(3): e208081, 2024 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-38181313

RESUMO

BACKGROUND AND OBJECTIVES: Despite the common occurrence of neurologic complications during extracorporeal membrane oxygenation (ECMO) support, data on long-term neuropsychiatric, neurocognitive, and functional outcomes are sparse. We aimed to determine the prevalence of long-term neuropsychiatric symptoms, neurocognitive and functional impairment, and favorable neurologic outcomes in adult patients who receive ECMO. METHODS: PubMed, Embase, Cochrane, Web of Science, and Scopus were searched for text related to ECMO and neuropsychiatric, neurocognitive, and functional outcomes from inception to May 3, 2023. Our primary outcome was the prevalence of neuropsychiatric symptoms (pain/discomfort, anxiety, depression, posttraumatic stress disorder [PTSD], and sleep disturbance) at long-term (≥6 months) follow-up. Our secondary outcomes were the prevalence of neurocognitive impairment (memory, attention, and reasoning), functional impairment (daily activities, physical activity/mobility, and personal/self-care), and favorable neurologic outcomes (Cerebral Performance Category ≤2, modified Rankin scale ≤3, or Glasgow Outcome Scale ≥4). This study was registered in PROSPERO (CRD42023420565). RESULTS: We included 59 studies with 3,280 patients (median age 54 years, 69% male). The cohort consisted of 86% venoarterial (VA)-ECMO (n = 2,819) and 14% venovenous (VV)-ECMO (n = 461) patients. More than 10 tools were used to assess neuropsychiatric and neurocognitive outcomes, indicating a lack of standardization in assessment methodologies. The overall prevalence of neuropsychiatric symptoms was 41% (95% CI 33%-49%): pain/discomfort (52%, 95% CI 42%-63%), sleep disturbance (37%, 95% CI 0%-98%), anxiety (36%, 95% CI 27%-46%), depression (31%, 95% CI 22%-40%), and PTSD (18%, 95% CI 9%-29%). The prevalence of neurocognitive impairment was 38% (95% CI 13%-65%). The prevalence of functional impairment was 52% (95% CI 40%-64%): daily activities (54%, 95% CI 41%-66%), mobility (41%, 95% CI 28%-54%), and self-care (21%, 95% CI 13%-31%). The prevalence of neuropsychiatric symptoms in VV-ECMO patients was higher than that in VA-ECMO patients (55% [95% CI 34%-75%] vs 32% [95% CI 23%-41%], p = 0.01), though the prevalence of neurocognitive and functional impairment was not different between the groups. The prevalence of favorable neurologic outcomes was not different at various follow-ups: 3 months (23%, 95% CI 12%-36%), 6 months (25%, 95% CI 16%-35%), and ≥1 year (28%, 95% CI 21%-36%, p = 0.68). DISCUSSION: A substantial proportion of ECMO patients seemed to experience neuropsychiatric symptoms and neurocognitive and functional impairments at long-term follow-up. Considerable heterogeneity in methodology for gauging these outcomes exists, warranting the need for standardization. Multicenter prospective observational studies are indicated to further investigate risk factors for these outcomes in ECMO-supported patients.


Assuntos
Oxigenação por Membrana Extracorpórea , Transtornos do Sono-Vigília , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ansiedade , Transtornos de Ansiedade , Oxigenação por Membrana Extracorpórea/efeitos adversos , Dor
5.
J Thorac Cardiovasc Surg ; 167(5): 1766-1775, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-37160217

RESUMO

OBJECTIVE: Atrial fibrillation (AF), if left untreated, is associated with increased intermediate and long-term morbidity/mortality. Surgical treatment for AF is lacking standardization in patient selection and lesion set, despite clear support from multi-society guidelines. The aim of this study was to analyze a statewide cardiac surgery registry to establish whether or not there is an association between center volume and type of index procedure with performance of surgical ablation (SA) for AF, the lesion set chosen, and ablation technology used. METHODS: Adult, first-time, nonemergency patients with preoperative AF between 2014 and 2022 excluding standalone SA procedures from a statewide registry of Society of Thoracic Surgeons data were included (N = 4320). AF treatment variability by hospital volume (ordered from smallest to largest) and surgery type were examined with χ2 analyses. Hospital-level Spearman correlations compared hospital volume with proportion of AF patients treated with SA. RESULTS: Overall, 37% of patients with AF were ablated at the time of surgery (63% of mitral procedures, 26% of non-mitrals) and 15% had left atrial appendage management only. There was a significant temporal trend of increasing performance of SA for AF over time (Cochran-Armitage = 27.8; P < .001). Hospital cardiac surgery volume did not correlate with the proportion of AF patients treated with SA (rs = 0.19; P = .603) with a rate of SA below the state average for academic centers. Of cases with SA (n = 1582), only 43% had a biatrial lesion set. Procedures that involved mitral surgery were more likely to include a biatrial lesion set (χ2 = 392.3; P < .001) for both paroxysmal and persistent AF. Similarly, ablation technology use was variable by type of concomitant operation (χ2 = 219.0; P < .001) such that radiofrequency energy was more likely to be used in non-mitral procedures. CONCLUSIONS: These results indicate an increase in adoption of SA for AF over time. No association between greater hospital volume or academic status and performance of SA for AF was established. Similar to national data, the type of index procedure remains the most consistent factor in the decision to perform SA with a disconnect between AF pathophysiology and decision making on the type of SA performed. This analysis demonstrates a gap between evidence-based guidelines and real-world practice, highlighting an opportunity to confer the benefits of concomitant SA to more patients.


Assuntos
Fibrilação Atrial , Procedimentos Cirúrgicos Cardíacos , Ablação por Cateter , Cirurgia Torácica , Humanos , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/cirurgia , Fibrilação Atrial/complicações , Resultado do Tratamento , Procedimentos Cirúrgicos Cardíacos/efeitos adversos
6.
Int J Artif Organs ; 47(1): 25-34, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38053227

RESUMO

INTRODUCTION: Patients requiring postcardiotomy veno-arterial extracorporeal membrane oxygenation (V-A-ECMO) have a high risk of early mortality. In this analysis, we evaluated whether any interinstitutional difference exists in the results of postcardiotomy V-A-ECMO. METHODS: Studies on postcardiotomy V-A-ECMO were identified through a systematic review for individual patient data (IPD) meta-analysis. Analysis of interinstitutional results was performed using direct standardization, estimation of observed/expected in-hospital mortality ratio and propensity score matching. RESULTS: Systematic review of the literature yielded 31 studies. Data from 10 studies on 1269 patients treated at 25 hospitals were available for the present analysis. In-hospital mortality was 66.7%. The relative risk of in-hospital mortality was significantly higher in six hospitals. Observed versus expected in-hospital mortality ratio showed that four hospitals were outliers with significantly increased mortality rates, and one hospital had significantly lower in-hospital mortality rate. Participating hospitals were classified as underperforming and overperforming hospitals if their observed/expected in-hospital mortality was higher or lower than 1.0, respectively. Among 395 propensity score matched pairs, the overperforming hospitals had significantly lower in-hospital mortality (60.3% vs 71.4%, p = 0.001) than underperforming hospitals. Low annual volume of postcardiotomy V-A-ECMO tended to be predictive of poor outcome only when adjusted for patients' risk profile. CONCLUSIONS: In-hospital mortality after postcardiotomy V-A-ECMO differed significantly between participating hospitals. These findings suggest that in many centers there is room for improvement of the results of postcardiotomy V-A-ECMO.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Oxigenação por Membrana Extracorpórea , Humanos , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Oxigenação por Membrana Extracorpórea/efeitos adversos , Oxigenação por Membrana Extracorpórea/métodos , Mortalidade Hospitalar , Estudos Retrospectivos , Choque Cardiogênico/terapia
7.
Crit Care Med ; 52(3): 483-494, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-37921532

RESUMO

OBJECTIVES: Extracorporeal cardiopulmonary resuscitation (ECPR) serves as a lifesaving intervention for patients experiencing refractory cardiac arrest. With its expanding usage, there is a burgeoning focus on improving patient outcomes through optimal management in the acute phase after cannulation. This review explores systematic post-cardiac arrest management strategies, associated complications, and prognostication in ECPR patients. DATA SOURCES: A PubMed search from inception to 2023 using search terms such as post-cardiac arrest care, ICU management, prognostication, and outcomes in adult ECPR patients was conducted. STUDY SELECTION: Selection includes original research, review articles, and guidelines. DATA EXTRACTION: Information from relevant publications was reviewed, consolidated, and formulated into a narrative review. DATA SYNTHESIS: We found limited data and no established clinical guidelines for post-cardiac arrest care after ECPR. In contrast to non-ECPR patients where systematic post-cardiac arrest care is shown to improve the outcomes, there is no high-quality data on this topic after ECPR. This review outlines a systematic approach, albeit limited, for ECPR care, focusing on airway/breathing and circulation as well as critical aspects of ICU care, including analgesia/sedation, mechanical ventilation, early oxygen/C o2 , and temperature goals, nutrition, fluid, imaging, and neuromonitoring strategy. We summarize common on-extracorporeal membrane oxygenation complications and the complex nature of prognostication and withdrawal of life-sustaining therapy in ECPR. Given conflicting outcomes in ECPR randomized controlled trials focused on pre-cannulation care, a better understanding of hemodynamic, neurologic, and metabolic abnormalities and early management goals may be necessary to improve their outcomes. CONCLUSIONS: Effective post-cardiac arrest care during the acute phase of ECPR is paramount in optimizing patient outcomes. However, a dearth of evidence to guide specific management strategies remains, indicating the necessity for future research in this field.


Assuntos
Reanimação Cardiopulmonar , Oxigenação por Membrana Extracorpórea , Parada Cardíaca , Parada Cardíaca Extra-Hospitalar , Adulto , Humanos , Parada Cardíaca/terapia , Parada Cardíaca/etiologia , Reanimação Cardiopulmonar/métodos , Respiração Artificial , Oxigenação por Membrana Extracorpórea/métodos , Parada Cardíaca Extra-Hospitalar/terapia , Estudos Retrospectivos
8.
Res Sq ; 2023 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-38045281

RESUMO

Background: Low pulse pressure (PP) in venoarterial-extracorporeal membrane oxygenation (VA-ECMO) is a marker of cardiac dysfunction and has been associated with acute brain injury (ABI) as continuous-flow centrifugal pump may lead to endothelial dysregulation. Methods: We retrospectively analyzed adults (≥18 years) on "peripheral" VA-ECMO support for cardiogenic shock in the Extracorporeal Life Support Organization Registry (1/2018-7/2023). Cubic splines were used to establish a threshold (PP≤10 mmHg at 24 hours of ECMO support) for "early low" PP. ABI included central nervous system (CNS) ischemia, intracranial hemorrhage, brain death, and seizures. Multivariable logistic regressions were performed to examine whether PP≤10 mmHg was associated with ABI. Covariates included age, sex, body mass index, pre-ECMO variables (temporary mechanical support, vasopressors, cardiac arrest), on-ECMO variables (pH, PaO2, PaCO2), and on-ECMO complications (hemolysis, arrhythmia, renal replacement therapy). Results: Of 9,807 peripheral VA-ECMO patients (median age=57.4 years, 67% male), 8,294 (85%) had PP>10 mmHg vs. 1,513 (15%) had PP≤10 mmHg. Patients with PP≤10 mmHg experienced ABI more frequently vs. PP>10 mmHg (15% vs. 11%, p<0.001). After adjustment, PP≤10 mmHg was independently associated with ABI (adjusted odds ratio [aOR]=1.25, 95% confidence interval [CI]=1.06-1.48, p=0.01). CNS ischemia and brain death were more common in patients with PP≤10 mmHg vs. PP>10 mmHg (8% vs. 6%, p=0.008; 3% vs. 1%, p<0.001). PP≤10 mmHg was associated with CNS ischemia (aOR=1.26, 95%CI=1.02-1.56, p=0.03) but not intracranial hemorrhage (aOR=1.14, 95%CI=0.85-1.54, p=0.38). Conclusions: Early low PP (≤10 mmHg) at 24 hours of ECMO support was associated with ABI, particularly CNS ischemia, in peripheral VA-ECMO patients.

9.
Cells ; 12(11)2023 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-37296666

RESUMO

Extracorporeal membrane oxygenation (ECMO), in conjunction with its life-saving benefits, carries a significant risk of acute brain injury (ABI). Hypoxic-ischemic brain injury (HIBI) is one of the most common types of ABI in ECMO patients. Various risk factors, such as history of hypertension, high day 1 lactate level, low pH, cannulation technique, large peri-cannulation PaCO2 drop (∆PaCO2), and early low pulse pressure, have been associated with the development of HIBI in ECMO patients. The pathogenic mechanisms of HIBI in ECMO are complex and multifactorial, attributing to the underlying pathology requiring initiation of ECMO and the risk of HIBI associated with ECMO itself. HIBI is likely to occur in the peri-cannulation or peri-decannulation time secondary to underlying refractory cardiopulmonary failure before or after ECMO. Current therapeutics target pathological mechanisms, cerebral hypoxia and ischemia, by employing targeted temperature management in the case of extracorporeal cardiopulmonary resuscitation (eCPR), and optimizing cerebral O2 saturations and cerebral perfusion. This review describes the pathophysiology, neuromonitoring, and therapeutic techniques to improve neurological outcomes in ECMO patients in order to prevent and minimize the morbidity of HIBI. Further studies aimed at standardizing the most relevant neuromonitoring techniques, optimizing cerebral perfusion, and minimizing the severity of HIBI once it occurs will improve long-term neurological outcomes in ECMO patients.


Assuntos
Lesões Encefálicas , Oxigenação por Membrana Extracorpórea , Hipóxia-Isquemia Encefálica , Humanos , Oxigenação por Membrana Extracorpórea/efeitos adversos , Oxigenação por Membrana Extracorpórea/métodos , Perfusão , Isquemia , Hipóxia-Isquemia Encefálica/complicações , Lesões Encefálicas/etiologia
10.
Perfusion ; : 2676591231170978, 2023 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-37066850

RESUMO

INTRODUCTION: Postcardiotomy veno-arterial extracorporeal membrane oxygenation (V-A-ECMO) is associated with significant mortality. Identification of patients at very high risk for death is elusive and the decision to initiate V-A-ECMO is based on clinical judgment. The prognostic impact of pre-V-A-ECMO arterial lactate level in these critically ill patients has been herein evaluated. METHODS: A systematic review was conducted to identify studies on postcardiotomy VA-ECMO for the present individual patient data meta-analysis. RESULTS: Overall, 1269 patients selected from 10 studies were included in this analysis. Arterial lactate level at V-A-ECMO initiation was increased in patients who died during the index hospitalization compared to those who survived (9.3 vs 6.6 mmol/L, p < 0.0001). Accordingly, in hospital mortality increased along quintiles of pre-V-A-ECMO arterial lactate level (quintiles: 1, 54.9%; 2, 54.9%; 3, 67.3%; 4, 74.2%; 5, 82.2%, p < 0.0001). The best cut-off for arterial lactate was 6.8 mmol/L (in-hospital mortality, 76.7% vs. 55.7%, p < 0.0001). Multivariable multilevel mixed-effect logistic regression model including arterial lactate level significantly increased the area under the receiver operating characteristics curve (0.731, 95% CI 0.702-0.760 vs 0.679, 95% CI 0.648-0.711, DeLong test p < 0.0001). Classification and regression tree analysis showed the in-hospital mortality was 85.2% in patients aged more than 70 years with pre-V-A-ECMO arterial lactate level ≥6.8 mmol/L. CONCLUSIONS: Among patients requiring postcardiotomy V-A-ECMO, hyperlactatemia was associated with a marked increase of in-hospital mortality. Arterial lactate may be useful in guiding the decision-making process and the timing of initiation of postcardiotomy V-A-ECMO.

11.
J Clin Med ; 11(24)2022 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-36556021

RESUMO

BACKGROUND: It is unclear whether peripheral arterial cannulation is superior to central arterial cannulation for postcardiotomy veno-arterial extracorporeal membrane oxygenation (VA-ECMO). METHODS: A systematic review was conducted using PubMed, Scopus, and Google Scholar to identify studies on postcardiotomy VA-ECMO for the present individual patient data (IPD) meta-analysis. Analysis was performed according to the intention-to-treat principle. RESULTS: The investigators of 10 studies agreed to participate in the present IPD meta-analysis. Overall, 1269 patients were included in the analysis. Crude rates of in-hospital mortality after central versus peripheral arterial cannulation for VA-ECMO were 70.7% vs. 63.7%, respectively (adjusted OR 1.38, 95% CI 1.08-1.75). Propensity score matching yielded 538 pairs of patients with balanced baseline characteristics and operative variables. Among these matched cohorts, central arterial cannulation VA-ECMO was associated with significantly higher in-hospital mortality compared to peripheral arterial cannulation VA-ECMO (64.5% vs. 70.8%, p = 0.027). These findings were confirmed by aggregate data meta-analysis, which showed that central arterial cannulation was associated with an increased risk of in-hospital mortality compared to peripheral arterial cannulation (OR 1.35, 95% CI 1.04-1.76, I2 21%). CONCLUSIONS: Among patients requiring postcardiotomy VA-ECMO, central arterial cannulation was associated with an increased risk of in-hospital mortality compared to peripheral arterial cannulation. This increased risk is of limited magnitude, and further studies are needed to confirm the present findings and to identify the mechanisms underlying the potential beneficial effects of peripheral VA-ECMO.

12.
AAPS PharmSciTech ; 22(5): 169, 2021 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-34080086

RESUMO

Lutein has been used as a dietary supplement for the treatment of eye diseases, especially age-related macular degeneration. For oral formulations, we investigated lutein stability in artificial set-ups mimicking different physiological conditions and found that lutein was degraded over time under acidic conditions. To enhance the stability of lutein upon oral intake, we developed enteric-coated lutein solid dispersions (SD) by applying a polymer, hydroxypropyl methylcellulose acetate succinate (HPMCAS-LF), through a solvent-controlled precipitation method. The SD were characterized in crystallinity, morphology, and drug entrapment. In the dissolution profile of lutein SD, a F80 formulation showed resistance toward the acidic environment under simulated gastric conditions while exhibiting a bursting drug release under simulated intestinal conditions. Our results highlight the potential use of HPMCAS-LF as an effective matrix to enhance lutein bioavailability during oral delivery and to provide novel insights into the eye-care supplement industry, with direct benefits for the health of patients.


Assuntos
Luteína/síntese química , Luteína/farmacocinética , Metilcelulose/análogos & derivados , Disponibilidade Biológica , Cromatografia Líquida de Alta Pressão/métodos , Liberação Controlada de Fármacos , Estabilidade de Medicamentos , Humanos , Metilcelulose/síntese química , Metilcelulose/farmacocinética , Polímeros/síntese química , Polímeros/farmacocinética , Solubilidade , Solventes , Difração de Raios X/métodos
13.
AAPS PharmSciTech ; 21(8): 320, 2020 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-33180220

RESUMO

The development of an oral formulation that ensures increased bioavailability of drugs is a great challenge for pharmaceutical scientists. Among many oral formulation systems, a drug delivery system employing superporous networks was developed to provide a prolonged gastro-retention time as well as improved bioavailability of drugs with a narrow absorption window in the gastrointestinal tract. Superporous networks (SPNs) were prepared from chitosan by crosslinking with glyoxal and poly(vinyl alcohol) (PVA). The SPNs showed less porosity and decreased water uptake with an increase in the crosslinking density and content of PVA. Gastro-retentive tablets (GRTs) were formulated using hydroxypropyl methylcellulose (HPMC, a hydrophilic polymer) and the prepared SPNs. Ascorbic acid (AA), which is mainly absorbed in the proximal part of the small intestine, was selected as a model drug. The formulated GRTs exhibited no floating lag time and stayed afloat until the end of the dissolution test. The in vitro drug release from the GRTs decreased with a decrease in the water uptake of the SPNs. The profile of drug release from the GRTs corresponded to the first-order and Higuchi drug-release models. Overall, floating tablets composed of the SPNs and HPMC have potential as a favorable platform to ensure sustained release and improved bioavailability of drugs that are absorbed in the proximal part of the small intestine.


Assuntos
Preparações de Ação Retardada/administração & dosagem , Sistemas de Liberação de Medicamentos , Porosidade , Comprimidos , Disponibilidade Biológica , Liberação Controlada de Fármacos , Derivados da Hipromelose , Polímeros
14.
Arch Pharm Res ; 43(1): 46-57, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31993968

RESUMO

Over the past few decades, hyperthermia therapy (HTT) has become one of the most promising strategies to treat cancer. HTT has been applied with nanotechnology to overcome drawbacks such as non-selectivity and invasiveness and to maximize therapeutic efficacy. The high temperature of HTT induces protein denaturation that leads to apoptosis or necrosis. It can also enhance the effects of other cancer therapies because heat-damaged tissues reduce radioresistance and help accumulate anticancer drugs. Gold nanoparticles and superparamagnetic iron oxide with different energy sources are commonly used as hyperthermia agents. New types of nanoparticles such as those whose surface is coated with several polymers and those modified with targeting moieties have been studied as novel HTT agents. In this review, we introduce principles and applications of nanotechnology-based HTT using gold nanoparticles and superparamagnetic iron oxide.


Assuntos
Antineoplásicos/uso terapêutico , Ouro/química , Hipertermia Induzida , Nanopartículas Metálicas/química , Neoplasias/tratamento farmacológico , Animais , Antineoplásicos/química , Compostos Férricos/química , Humanos
15.
Pharmaceutics ; 11(6)2019 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-31234389

RESUMO

Nanotechnology-based photo-chemo combination therapy has been extensively investigated to improve therapeutic outcomes in anticancer treatment. Specifically, with the help of a singlet oxygen generated by the photosensitizer, the endocytosed nanoparticles are allowed to escape from the endosomal compartment, which is currently an obstacle in nanotechnology-based anticancer therapy. In this study, a liposomal complex system (Lipo (Pep, Ce6)), composed of a chlorin e6-conjugated di-block copolymer (PEG-PLL(-g-Ce6)) and a D-(KLAKLAK)2 peptide loading liposome (Lipo (Pep)), was developed and evaluated for its anticancer activity. Due to the membrane lytic ability of the D-(KLAKLAK)2 peptide and the membrane disruptive effect of the singlet oxygen generated from chlorin e6, Lipo (Pep, Ce6) accelerated the disruption of the endosomal compartment, and exhibited strong synergistic anticancer activity in vitro. The prepared liposomal complex system could potentially maximize the efficacy of the nanotechnology-based photo-chemo combination therapy, and can be regarded as a novel, versatile strategy in advanced tumor therapy.

16.
Drug Deliv ; 25(1): 1362-1371, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29869563

RESUMO

Docetaxel (DTX)-loaded polymeric micelles (DTBM) were formulated using the triblock copolymer, poly(ethylene glycol)-polylactide-poly(ethylene glycol) (PEG-PLA-PEG), to comprehensively study their pharmaceutical application as anticancer nanomedicine. DTBM showed a stable formulation of anticancer nanomedicine that could be reconstituted after lyophilization (DTBM-R) in the presence of PEG 2000 and D-mannitol (Man) as surfactant and protectant, respectively. DTBM-R showed a particle size less than 150 nm and greater than 90% of DTX recovery after reconstitution. The robustly formed micelles might minimize systemic toxicity due to their sustained drug release and also maximize antitumor efficacy through increased accumulation and release of DTX from the micelles. From the pharmaceutical development point of view, DTBM-R showing successful reconstitution could be considered as a potent nanomedicine for tumor treatment.


Assuntos
Antineoplásicos/administração & dosagem , Antineoplásicos/química , Poliésteres/química , Polietilenoglicóis/química , Polímeros/química , Taxoides/química , Animais , Linhagem Celular Tumoral , Química Farmacêutica/métodos , Preparações de Ação Retardada/administração & dosagem , Preparações de Ação Retardada/química , Docetaxel , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos/métodos , Humanos , Células KB , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Micelas , Nanomedicina/métodos , Tamanho da Partícula , Tensoativos/química , Taxoides/administração & dosagem
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