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1.
Cerebrovasc Dis ; 53(1): 54-61, 2024.
Article in English | MEDLINE | ID: mdl-37231793

ABSTRACT

INTRODUCTION: Over half of patients with acute ischemic stroke are overweight or obese as defined by a body mass index (BMI) ≥25 kg/m2. Professional and government agencies recommend weight management for these persons to improve risk factors for cardiovascular disease, including hypertension, dyslipidemia, vascular inflammation, and diabetes. However, approaches to weight loss have not been adequately tested specifically in patients with stroke. In anticipation of a larger trial with vascular or functional outcomes, we tested the feasibility and safety of a 12-week partial meal replacement (PMR) intervention for weight loss in overweight or obese patients with a recent ischemic stroke. METHODS: This randomized open-label trial enrolled participants from December 2019 to February 2021 (with hiatus from March to August 2020 due to COVID-19 pandemic restrictions on research). Eligible patients had a recent ischemic stroke and BMI 27-49.9 kg/m2. Patients were randomized to a PMR diet (OPTAVIA® Optimal Weight 4 & 2 & 1 Plan®) plus standard care (SC) or SC alone. The PMR diet consisted of four meal replacements supplied to participants, two meals with lean protein and vegetables (self-prepared or supplied), and a healthy snack (also self-prepared or supplied). The PMR diet provided 1,100-1,300 calories per day. SC consisted of one instructional session on a healthy diet. Co-primary outcomes were ≥5% weight loss at 12 weeks and to identify barriers to successful weight loss among participants assigned to PMR. Safety outcomes included hospitalization, falls, pneumonia, or hypoglycemia requiring treatment by self or others. Due to the COVID-19 pandemic, study visits after August 2020 were by remote communication. RESULTS: We enrolled 38 patients from two institutions. Two patients in each arm were lost and could not be included in outcome analyses. At 12 weeks, 9/17 patients in the PMR group and 2/17 patients in the SC group achieved ≥5% weight loss (52.9% vs. 11.9%; Fisher's exact p = 0.03). Mean percent weight change in the PMR group was -3.0% (SD 13.7) and -2.6% (SD 3.4) in the SC group (Wilcoxon rank-sum p = 0.17). No adverse events were attributed to study participation. Some participants had difficulty completing home monitoring of weight. In the PMR group, participants reported that food cravings and dislike for some food products were barriers to weight loss. CONCLUSION: A PMR diet after ischemic stroke is feasible, safe, and effective for weight loss. In future trials, in-person or improved remote outcome monitoring may reduce anthropometric data variation.


Subject(s)
COVID-19 , Ischemic Stroke , Humans , Overweight , Diet, Reducing/adverse effects , Diet, Reducing/methods , Pandemics , Obesity/complications , Obesity/diagnosis , Obesity/therapy , Weight Loss , Meals
3.
NPJ Vaccines ; 8(1): 97, 2023 Jul 10.
Article in English | MEDLINE | ID: mdl-37429853

ABSTRACT

Opioid use disorders (OUD) and opioid-related fatal overdoses are a public health concern in the United States. Approximately 100,000 fatal opioid-related overdoses occurred annually from mid-2020 to the present, the majority of which involved fentanyl or fentanyl analogs. Vaccines have been proposed as a therapeutic and prophylactic strategy to offer selective and long-lasting protection against accidental or deliberate exposure to fentanyl and closely related analogs. To support the development of a clinically viable anti-opioid vaccine suitable for human use, the incorporation of adjuvants will be required to elicit high titers of high-affinity circulating antibodies specific to the target opioid. Here we demonstrate that the addition of a synthetic TLR7/8 agonist, INI-4001, but not a synthetic TLR4 agonist, INI-2002, to a candidate conjugate vaccine consisting of a fentanyl-based hapten, F1, conjugated to the diphtheria cross-reactive material (CRM), significantly increased generation of high-affinity F1-specific antibody concentrations, and reduced drug distribution to the brain after fentanyl administration in mice.

4.
Stroke ; 54(3): e109-e121, 2023 03.
Article in English | MEDLINE | ID: mdl-36655570

ABSTRACT

At least 240 000 individuals experience a transient ischemic attack each year in the United States. Transient ischemic attack is a strong predictor of subsequent stroke. The 90-day stroke risk after transient ischemic attack can be as high as 17.8%, with almost half occurring within 2 days of the index event. Diagnosing transient ischemic attack can also be challenging given the transitory nature of symptoms, often reassuring neurological examination at the time of evaluation, and lack of confirmatory testing. Limited resources, such as imaging availability and access to specialists, can further exacerbate this challenge. This scientific statement focuses on the correct clinical diagnosis, risk assessment, and management decisions of patients with suspected transient ischemic attack. Identification of high-risk patients can be achieved through use of comprehensive protocols incorporating acute phase imaging of both the brain and cerebral vasculature, thoughtful use of risk stratification scales, and ancillary testing with the ultimate goal of determining who can be safely discharged home from the emergency department versus admitted to the hospital. We discuss various methods for rapid yet comprehensive evaluations, keeping resource-limited sites in mind. In addition, we discuss strategies for secondary prevention of future cerebrovascular events using maximal medical therapy and patient education.


Subject(s)
Ischemic Attack, Transient , Stroke , Humans , United States , Ischemic Attack, Transient/diagnosis , Ischemic Attack, Transient/therapy , Ischemic Attack, Transient/complications , American Heart Association , Stroke/diagnosis , Stroke/prevention & control , Emergency Service, Hospital , Risk Reduction Behavior
6.
Sci Adv ; 8(16): eabm3952, 2022 Apr 22.
Article in English | MEDLINE | ID: mdl-35442729

ABSTRACT

Brain imaging is essential to the clinical management of patients with ischemic stroke. Timely and accessible neuroimaging, however, can be limited in clinical stroke pathways. Here, portable magnetic resonance imaging (pMRI) acquired at very low magnetic field strength (0.064 T) is used to obtain actionable bedside neuroimaging for 50 confirmed patients with ischemic stroke. Low-field pMRI detected infarcts in 45 (90%) patients across cortical, subcortical, and cerebellar structures. Lesions as small as 4 mm were captured. Infarcts appeared as hyperintense regions on T2-weighted, fluid-attenuated inversion recovery and diffusion-weighted imaging sequences. Stroke volume measurements were consistent across pMRI sequences and between low-field pMRI and conventional high-field MRI studies. Low-field pMRI stroke volumes significantly correlated with stroke severity and functional outcome at discharge. These results validate the use of low-field pMRI to obtain clinically useful imaging of stroke, setting the stage for use in resource-limited environments.

7.
J Stroke Cerebrovasc Dis ; 30(10): 106016, 2021 Oct.
Article in English | MEDLINE | ID: mdl-34325273

ABSTRACT

OBJECTIVES: Transient ischemic attack (TIA) can be a warning sign of an impending stroke. The objective of our study is to assess the feasibility, safety, and cost savings of a comprehensive TIA protocol in the emergency room for low-risk TIA patients. MATERIALS AND METHODS: This is a retrospective, single-center cohort study performed at an academic comprehensive stroke center. We implemented an emergency department-based TIA protocol pathway for low-risk TIA patients (defined as ABCD2 score < 4 and without significant vessel stenosis) who were able to undergo vascular imaging and a brain MRI in the emergency room. Patients were set up with rapid outpatient follow-up in our stroke clinic and scheduled for an outpatient echocardiogram, if indicated. We compared this cohort to TIA patients admitted prior to the implementation of the TIA protocol who would have qualified. Outcomes of interest included length of stay, hospital cost, radiographic and echocardiogram findings, recurrent neurovascular events within 30 days, and final diagnosis. RESULTS: A total of 138 patients were assessed (65 patients in the pre-pathway cohort, 73 in the expedited, post-TIA pathway implementation cohort). Average time from MRI order to MRI end was 6.4 h compared to 2.3 h in the pre- and post-pathway cohorts, respectively (p < 0.0001). The average length of stay for the pre-pathway group was 28.8 h in the pre-pathway cohort compared to 7.7 h in the post-pathway cohort (p < 0.0001). There were no differences in neuroimaging or echocardiographic findings. There were no differences in the 30 days re-presentation for stroke or TIA or mortality between the two groups. The direct cost per TIA admission was $2,944.50 compared to $1,610.50 for TIA patients triaged through the pathway at our institution. CONCLUSIONS: This study demonstrates the feasibility, safety, and cost-savings of a comprehensive, emergency department-based TIA protocol. Further study is needed to confirm overall benefit of an expedited approach to TIA patient management and guide clinical practice recommendations.


Subject(s)
Delivery of Health Care, Integrated/economics , Emergency Service, Hospital/economics , Hospital Costs , Ischemic Attack, Transient/economics , Ischemic Attack, Transient/therapy , Outcome and Process Assessment, Health Care/economics , Aged , Aged, 80 and over , Clinical Protocols , Cost Savings , Cost-Benefit Analysis , Decision Support Techniques , Feasibility Studies , Female , Humans , Ischemic Attack, Transient/diagnostic imaging , Ischemic Attack, Transient/mortality , Length of Stay/economics , Male , Middle Aged , Predictive Value of Tests , Retrospective Studies , Risk Assessment , Risk Factors , Time Factors , Treatment Outcome , Triage/economics
8.
Stroke ; 51(9): 2664-2673, 2020 09.
Article in English | MEDLINE | ID: mdl-32755347

ABSTRACT

BACKGROUND: Anecdotal reports suggest fewer patients with stroke symptoms are presenting to hospitals during the coronavirus disease 2019 (COVID-19) pandemic. We quantify trends in stroke code calls and treatments at 3 Connecticut hospitals during the local emergence of COVID-19 and examine patient characteristics and stroke process measures at a Comprehensive Stroke Center (CSC) before and during the pandemic. METHODS: Stroke code activity was analyzed from January 1 to April 28, 2020, and corresponding dates in 2019. Piecewise linear regression and spline models identified when stroke codes in 2020 began to decline and when they fell below 2019 levels. Patient-level data were analyzed in February versus March and April 2020 at the CSC to identify differences in patient characteristics during the pandemic. RESULTS: A total of 822 stroke codes were activated at 3 hospitals from January 1 to April 28, 2020. The number of stroke codes/wk decreased by 12.8/wk from February 18 to March 16 (P=0.0360) with nadir of 39.6% of expected stroke codes called from March 10 to 16 (30% decrease in total stroke codes during the pandemic weeks in 2020 versus 2019). There was no commensurate increase in within-network telestroke utilization. Compared with before the pandemic (n=167), pandemic-epoch stroke code patients at the CSC (n=211) were more likely to have histories of hypertension, dyslipidemia, coronary artery disease, and substance abuse; no or public health insurance; lower median household income; and to live in the CSC city (P<0.05). There was no difference in age, sex, race/ethnicity, stroke severity, time to presentation, door-to-needle/door-to-reperfusion times, or discharge modified Rankin Scale. CONCLUSIONS: Hospital presentation for stroke-like symptoms decreased during the COVID-19 pandemic, without differences in stroke severity or early outcomes. Individuals living outside of the CSC city were less likely to present for stroke codes at the CSC during the pandemic. Public health initiatives to increase awareness of presenting for non-COVID-19 medical emergencies such as stroke during the pandemic are critical.


Subject(s)
Brain Ischemia/epidemiology , Intracranial Hemorrhages/epidemiology , Stroke/epidemiology , Time-to-Treatment/statistics & numerical data , Aged , Aged, 80 and over , Betacoronavirus , Brain Ischemia/diagnosis , Brain Ischemia/physiopathology , Brain Ischemia/therapy , COVID-19 , Cohort Studies , Comorbidity , Connecticut/epidemiology , Coronary Artery Disease/epidemiology , Coronavirus Infections/epidemiology , Dyslipidemias/epidemiology , Emergency Medical Services , Ethnicity , Female , Humans , Hypertension/epidemiology , Income , Insurance, Health , Intracranial Hemorrhages/diagnosis , Intracranial Hemorrhages/physiopathology , Intracranial Hemorrhages/therapy , Male , Medically Uninsured , Middle Aged , Outcome and Process Assessment, Health Care , Pandemics , Pneumonia, Viral/epidemiology , Retrospective Studies , SARS-CoV-2 , Severity of Illness Index , Stroke/diagnosis , Stroke/physiopathology , Stroke/therapy , Substance-Related Disorders/epidemiology , Telemedicine , Thrombectomy , Thrombolytic Therapy
9.
Mater Sci Eng C Mater Biol Appl ; 111: 110760, 2020 Jun.
Article in English | MEDLINE | ID: mdl-32279783

ABSTRACT

Nanoparticle-protein interactions under conditions mimicking physiology determine how nanoparticles (NPs) will behave inside blood vessels and, therefore, the overall outcome of the drug-delivery system. Here, for the first time, we explore the effects of bio-mimicking shear stress and protein corona conditions on novel active targeting of clickable fattigation nanoparticles (NPs) for cancer therapy. Active targeting dibenzocyclooctyne-functionalized biocompatible gelatin-oleic NPs (GON-DBCOs) via a bioorthogonal click reaction were prepared by the desolvation method for delivery of docetaxel (DTX) to lung and breast cancer models. The effect of shear stress (5 dyne/cm2) and human serum albumin (HSA) protein corona on the cellular behavior of NPs was explored under a dynamic microfluidic system in lung (A549) and breast (MCF-7) cancer cell lines. The developed drug-loaded NPs had a particle size of 300 nm, a narrow size distribution, positive zeta potential, high encapsulation efficacy (72.4%), and spherical morphology. The particle size of the protein corona-coated NPs increased to 341 nm with a negative zeta potential. The inhibitory dose (IC50) increased approximately 3- and 42-fold in A549 and MCF-7 cells, respectively, under dynamic microfluidic conditions compared to static conditions. Cellular uptake was significantly decreased in the presence of shear stress and a protein corona, compared with static conditions, in both lung (A549, **p < 0.01) and breast (MCF-7, *p < 0.05) cancer cell lines. Clathrin-and energy-dependent pathways were found to be involved in the cellular uptake of NPs. This study could serve as a vital tool for the evaluation of NPs under aggressive bio-mimicking conditions comprising shear stress and a protein corona to predict the in vivo performance of NPs and support the preclinical and clinical translation of NP drug delivery systems.


Subject(s)
Docetaxel/chemistry , Drug Carriers/chemistry , Gelatin/chemistry , Nanoparticles/chemistry , Protein Corona/chemistry , Biocompatible Materials/chemistry , Cell Line, Tumor , Cell Survival/drug effects , Click Chemistry , Docetaxel/metabolism , Docetaxel/pharmacology , Drug Liberation , Humans , Microscopy, Confocal , Particle Size , Serum Albumin, Human/chemistry , Shear Strength
10.
J Vasc Surg ; 72(5): 1720-1727.e1, 2020 11.
Article in English | MEDLINE | ID: mdl-32249043

ABSTRACT

OBJECTIVE: Smoking is a significant modifiable risk factor in the pathogenesis of carotid artery disease and has been shown to be a predictor of worse outcomes after vascular surgery. However, the effect of active smoking on outcomes of patients undergoing carotid endarterectomy is unknown. This study analyzed the outcomes of carotid endarterectomy by smoking status in a large national database. METHODS: The American College of Surgeons National Surgical Quality Improvement Program targeted carotid endarterectomy files (2011-2017) were reviewed. Patients were stratified according to smoking status, and outcomes were compared using propensity score matching (1:1) based on preoperative characteristics. RESULTS: During the study period, 26,293 patients underwent carotid endarterectomy, with 19,282 (73.34%) nonsmokers and 7011 (26.66%) smokers. Smokers were more likely to be younger, to have chronic obstructive pulmonary disease, to have a symptomatic presentation, and to have higher anatomic risk (P < .05). Smokers were also more likely to have emergent surgery, to have general anesthesia, and to be reintubated (P < .05). After propensity matching, 5354 nonsmokers were matched with 5354 smokers who underwent carotid endarterectomy. Smokers were at significantly higher risk for death, with an odds ratio of 1.93 (confidence interval, 1.18-3.13). CONCLUSIONS: Smokers are at increased risk for death after carotid endarterectomy compared with matched counterparts. Smoking should be considered an important risk factor for worse outcomes, and patients should be strongly counseled on the importance of smoking cessation before undergoing carotid endarterectomy.


Subject(s)
Carotid Artery Diseases/surgery , Endarterectomy, Carotid/adverse effects , Postoperative Complications/epidemiology , Smoking/adverse effects , Aged , Aged, 80 and over , Databases, Factual , Female , Humans , Length of Stay , Male , Middle Aged , Operative Time , Propensity Score , Retrospective Studies , Risk Factors , United States
11.
CNS Spectr ; 25(4): 460-467, 2020 08.
Article in English | MEDLINE | ID: mdl-31511119

ABSTRACT

Wake-up stroke (WUS) or ischemic stroke occurring during sleep accounts for 14%-29.6% of all ischemic strokes. Management of WUS is complicated by its narrow therapeutic time window and attributable risk factors, which can affect the safety and efficacy of administering intravenous (IV) tissue plasminogen activator (t-PA). This manuscript will review risk factors of WUS, with a focus on obstructive sleep apnea, potential mechanisms of WUS, and evaluate studies assessing safety and efficacy of IV t-PA treatment in WUS patients guided by neuroimaging to estimate time of symptom onset. The authors used PubMed (1966 to March 2018) to search for the term "Wake-Up Stroke" cross-referenced with "pathophysiology," ''pathogenesis," "pathology," "magnetic resonance imaging," "obstructive sleep apnea," or "treatment." English language Papers were reviewed. Also reviewed were pertinent papers from the reference list of the above-matched manuscripts. Studies that focused only on acute Strokes with known-onset of symptoms were not reviewed. Literature showed several potential risk factors associated with increased risk of WUS. Although the onset of WUS is unknown, a few studies investigated the potential benefit of magnetic resonance imaging (MRI) in estimating the age of onset which encouraged conducting clinical trials assessing the efficacy of MRI-guided thrombolytic therapy in WUS.


Subject(s)
Ischemic Stroke/physiopathology , Sleep , Humans , Ischemic Stroke/diagnostic imaging , Ischemic Stroke/drug therapy , Ischemic Stroke/epidemiology , Neuroimaging/methods , Sleep Apnea, Obstructive/epidemiology , Thrombolytic Therapy/methods
12.
Infect Disord Drug Targets ; 20(5): 598-610, 2020.
Article in English | MEDLINE | ID: mdl-31613729

ABSTRACT

For a number of decades, schistosomiasis has remained a public threat and an economic burden in a number of countries, directly impacting over 200 million people. The past 15 years have seen tremendous progress in the development of high-throughput methods for targeting or compound selection that are vital to early-stage schistosome drug discovery research. Genomewide approaches to analyze gene expression at the transcriptional and other -omic levels have helped immensely for gaining insight into the pathways and mechanisms involved in the schistosomiasis and it is expected to revolutionize the drug discovery as well as related diagnostics. This review discusses the most recent progress of pharmacology and genomics concerning schistosomiasis with a focus on drug discovery and diagnostic tools. It also provides chemical structural insights of promising targets along with available in vitro and/or in vivo data. Although significant research has been done to identify new molecules for the treatment and new methods for diagnosis, the necessity of new options for the sustainable control of schistosomiasis remains a great challenge.


Subject(s)
Anthelmintics/pharmacology , Gene Regulatory Networks/drug effects , Schistosomiasis/genetics , Animals , Anthelmintics/chemistry , Anthelmintics/therapeutic use , Drug Discovery , Gene Expression Profiling/methods , Gene Expression Regulation/drug effects , Genomics/methods , Humans , Precision Medicine , Schistosoma/classification , Schistosoma/drug effects , Schistosomiasis/drug therapy
14.
Stroke ; 50(7): 1797-1804, 2019 07.
Article in English | MEDLINE | ID: mdl-31159701

ABSTRACT

Background and Purpose- After large-vessel intracranial occlusion, the fate of the ischemic penumbra, and ultimately final infarct volume, largely depends on tissue perfusion. In this study, we evaluated whether blood pressure reduction and sustained relative hypotension during endovascular thrombectomy are associated with infarct progression and functional outcome. Methods- We identified consecutive patients with large-vessel intracranial occlusion ischemic stroke who underwent mechanical thrombectomy at 2 comprehensive stroke centers. Intraprocedural mean arterial pressure (MAP) was monitored throughout the procedure. ΔMAP was calculated as the difference between admission MAP and lowest MAP during endovascular thrombectomy until recanalization. Sustained hypotension was measured as the area between admission MAP and continuous measurements of intraprocedural MAP (aMAP). Final infarct volume was measured using magnetic resonance imaging at 24 hours, and functional outcome was assessed using the modified Rankin Scale at discharge and 90 days. Associations with outcome were analyzed using linear and ordinal multivariable logistic regression. Results- Three hundred ninety patients (mean age 71±14 years, mean National Institutes of Health Stroke Scale score of 17) were included in the study; of these, 280 (72%) achieved Thrombolysis in Cerebral Infarction 2B/3 reperfusion. Eighty-seven percent of patients experienced MAP reductions during endovascular thrombectomy (mean 31±20 mm Hg). ΔMAP was associated with greater infarct growth ( P=0.036) and final infarct volume ( P=0.035). Mean ΔMAP among patients with favorable outcomes (modified Rankin Scale score, 0-2) was 20±21 mm Hg compared with 30±24 mm Hg among patients with poor outcome ( P=0.002). In the multivariable analysis, ΔMAP was independently associated with higher (worse) modified Rankin Scale scores at discharge (adjusted odds ratio per 10 mm Hg, 1.17; 95% CI, 1.04-1.32; P=0.009) and at 90 days (adjusted odds ratio per 10 mm Hg, 1.22; 95% CI, 1.07-1.38; P=0.003). The association between aMAP and outcome was also significant at discharge ( P=0.002) and 90 days ( P=0.001). Conclusions- Blood pressure reduction before recanalization is associated with larger infarct volumes and worse functional outcomes for patients affected by large-vessel intracranial occlusion stroke. These results underscore the importance of BP management during endovascular thrombectomy and highlight the need for further investigation of blood pressure management after large-vessel intracranial occlusion stroke.


Subject(s)
Blood Pressure , Cerebral Infarction/therapy , Stroke/therapy , Thrombectomy/methods , Aged , Aged, 80 and over , Arterial Pressure , Brain Ischemia/diagnostic imaging , Brain Ischemia/physiopathology , Brain Ischemia/therapy , Cerebral Infarction/diagnostic imaging , Cerebral Infarction/physiopathology , Disease Progression , Female , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Recovery of Function , Retrospective Studies , Stroke/diagnostic imaging , Stroke/physiopathology , Treatment Outcome
15.
Int J Pharm ; 564: 124-135, 2019 Jun 10.
Article in English | MEDLINE | ID: mdl-30991133

ABSTRACT

The aim of this study was to investigate the impact of different chain length fatty acids on physicochemical properties and cancer targeting of fattigation-platform nanoparticles (NPs). Two different types of fatty acids (short chain, 2-hydroxybutyric acid, C4; long chain, oleic acid, C18:1) were successfully conjugated to human serum albumin (HSA) via simple 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDC) coupling reaction. These conjugates readily formed HSA-C4 and HSA-C18:1 NPs which showed good stability in serum and desirable biocompatibility with normal cell line (HEK293T). Doxorubicin hydrochloride (DOX) was efficiently loaded into NPs by incubation process via electrostatic interaction. The structure, morphology, and texture of DOX-loaded NPs were characterized by Transmission electron microscopy (TEM) equipped with Energy-dispersive X-ray spectroscopy (EDS). The initial burst release of DOX-loaded NPs was controlled by the presence and chain length of fatty acids. In vitro cytotoxicity studies with three cancer cell lines (A549, HT-29, and PANC-1) suggested that fattigation-platform NPs have distinctive cytotoxic effects compared to Doxil®. Confocal microscopy and flow cytometry exhibited that the cellular uptake of DOX-loaded NPs was varied by the different chain lengths of fatty acids. It was evident that the chain length of fatty acids in the fattigation-platform NPs could play a vital role in varying physicochemical properties and cancer cell targeting of NPs.


Subject(s)
Antibiotics, Antineoplastic/chemistry , Doxorubicin/chemistry , Hydroxybutyrates/chemistry , Nanoparticles/chemistry , Oleic Acid/chemistry , Serum Albumin, Human/chemistry , Antibiotics, Antineoplastic/administration & dosage , Cell Line, Tumor , Cell Survival/drug effects , Doxorubicin/administration & dosage , Drug Liberation , HEK293 Cells , Humans , Hydroxybutyrates/administration & dosage , Nanoparticles/administration & dosage , Neoplasms/drug therapy , Oleic Acid/administration & dosage , Serum Albumin, Human/administration & dosage
16.
Colloids Surf B Biointerfaces ; 170: 179-186, 2018 Oct 01.
Article in English | MEDLINE | ID: mdl-29906703

ABSTRACT

Albumin is the most abundant protein in blood, and is the most frequently identified protein in the protein corona of nanoparticles (NPs). Thus, albumin plays an important role in modulating NPs' physicochemical properties and bioavailability. In this study, the effect of bovine serum albumin (BSA) on gelatin-oleic nanoparticles' (GONs) physicochemical properties and cellular uptake were evaluated. Coumarin-6 was used as indicator to track the cellular uptake of GONs. The binding of BSA onto the GON surface increased the size, slightly reduced the negative net charge of the GON, and improved GON stability. The presence of BSA in cell culture media reduced the cellular uptake of BSA-uncoated GONs on human embryonic kidney cells 293 (HEK 293) and human adenocarcinoma alveolar basal epithelial cells (A549) in the media without FBS addition. Pre-coated BSA corona decreased cellular uptake of GONs in A549 cells in the media, with and without supplemented with 10% fetal bovine serum (FBS) but drastically increased cellular uptake on HEK 293 cells. BSA could be used to modulate protein corona as an endogenous ligand in NP design simply by mixing or incubating BSA with NPs before in vivo administration to inhibit or induce cellular uptake in specific cell types.


Subject(s)
Nanoparticles/chemistry , Protein Corona/chemistry , Serum Albumin, Bovine/chemistry , Animals , Cattle , Cell Line, Tumor , HEK293 Cells , Humans , Particle Size , Surface Properties
17.
Int J Pharm ; 545(1-2): 101-112, 2018 Jul 10.
Article in English | MEDLINE | ID: mdl-29698822

ABSTRACT

The principles of bioorthogonal click chemistry and metabolic glycoengineering were applied to produce targeted anti-cancer drug delivery via fattigation-platform-based gelatin-oleic nanoparticles. A sialic acid precursor (Ac4ManNAz) was introduced to the cell surface. Gelatin and oleic acid were conjugated by 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride/N-hydroxysuccinimide (EDC/NHS) chemistry with the subsequent covalent attachment of dibenzocyclooctyne (DBCO) in a click reaction on the cell surface. The physicochemical properties, drug release, in vitro cytotoxicity, and cellular uptake of DBCO-conjugated gelatin oleic nanoparticles (GON-DBCO; particle size, ∼240 nm; zeta potential, 6 mV) were evaluated. Doxorubicin (DOX) was used as a model drug and compared with the reference product, Caelyx®. A549 and MCF-7 cell lines were used for the in vitro studies. GON-DBCO showed high DOX loading and encapsulation efficiencies. In A549 cells, the IC50 value for GON-DBCO-DOX (1.29 µg/ml) was six times lower than that of Caelyx® (10.54 µg/ml); in MCF-7 cells, the IC50 values were 1.78 µg/ml and 2.84 µg/ml, respectively. Confocal microscopy confirmed the click reaction between GON-DBCO and Ac4ManNAz on the cell surface. Flow cytometry data revealed that the intracellular uptake of GON-DBCO-DOX was approximately two times greater than that of GON-DOX and Caelyx®. Thus, the newly designed GON-DBCO-DOX provided a safe and efficient drug delivery system to actively target the anticancer agents.


Subject(s)
Antibiotics, Antineoplastic/chemistry , Click Chemistry , Doxorubicin/chemistry , Drug Carriers , Gelatin/chemistry , Nanoparticles , Oleic Acid/chemistry , Technology, Pharmaceutical/methods , A549 Cells , Antibiotics, Antineoplastic/administration & dosage , Antibiotics, Antineoplastic/metabolism , Breast Neoplasms/drug therapy , Breast Neoplasms/pathology , Cell Survival/drug effects , Doxorubicin/administration & dosage , Doxorubicin/metabolism , Drug Compounding , Drug Liberation , Female , Flow Cytometry , Humans , Lung Neoplasms/drug therapy , Lung Neoplasms/pathology , MCF-7 Cells , Microscopy, Confocal , Nanotechnology , Particle Size , Time Factors
18.
J Neuroophthalmol ; 38(3): 328-333, 2018 09.
Article in English | MEDLINE | ID: mdl-29369960

ABSTRACT

BACKGROUND: To evaluate the risk of concurrent acute ischemic stroke and monocular vision loss (MVL) of vascular etiology. DESIGN: Retrospective, cross-sectional study. SUBJECTS: Patients aged 18 or older diagnosed with MVL of suspected or confirmed vascular etiology who had no other neurologic deficits and who received brain MRI within 7 days of onset of visual symptoms were included. METHODS: A medical record review was performed from 2013 to 2016 at Yale New Haven Hospital. Patients were included if vision loss was unilateral and due to transient monocular vision loss (TMVL), central retinal artery occlusion (CRAO), or branch retinal artery occlusion (BRAO). Any patients with neurologic deficits other than vision loss were excluded. Other exclusion criteria were positive visual phenomena, nonvascular intraocular pathology, and intracranial pathology other than ischemic stroke. MAIN OUTCOME MEASURES: The presence or absence of acute stroke on diffusion-weighted imaging (DWI) on brain MRI. RESULTS: A total of 641 records were reviewed, with 293 patients found to have MVL. After excluding those with focal neurologic deficits, there were 41 patients who met the inclusion criteria and received a brain MRI. Eight of the 41 subjects (19.5%) were found to have findings on brain MRI positive for acute cortical strokes. The proportion of lesion positive MRI was 1/23 (4.3%) in TMVL subjects, 4/12 (33.3%) in CRAO subjects, and 2/5 (40%) in BRAO subjects. Brain computed tomography (CT) scans were not able to identify the majority of acute stroke lesions in this study. CONCLUSIONS: Patients with MVL of vascular etiology such as TMVL, CRAO, or BRAO may have up to 19.5% risk of concurrent ischemic stroke, even when there are no other neurologic deficits. These strokes were detected acutely with brain MRI using DWI but were missed on CT.


Subject(s)
Blindness/complications , Brain Ischemia/complications , Vision, Monocular , Visual Acuity , Acute Disease , Adult , Aged , Aged, 80 and over , Blindness/diagnosis , Blindness/physiopathology , Brain Ischemia/diagnosis , Cross-Sectional Studies , Diffusion Magnetic Resonance Imaging , Female , Humans , Male , Middle Aged , Retrospective Studies
19.
Colloids Surf B Biointerfaces ; 159: 571-579, 2017 Nov 01.
Article in English | MEDLINE | ID: mdl-28854413

ABSTRACT

A major hurdle in cancer treatment is the precise targeting of drugs to the cancer site. As many cancer cells overexpress the transferrin receptor (TfR), the transferrin (Tf)-TfR interaction is widely exploited to target cancer cells. In this study, novel amphiphilic apo-Tf stearic acid (TfS) conjugates were prepared and characterized by Fourier transform infrared (FTIR) spectroscopy, matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF) mass spectrometry, and trinitrobenzenesulfonic acid (TNBS) assay. The prepared TfS conjugates were readily self-assembled in water to form nanoparticles (NPs), consisting of TfS as a core of NPs, whose sizes and zeta potentials were determined by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and a particle size analyzer. Hydrophilic water-soluble doxorubicin (DOX) was chosen as a model drug. DOX-loaded TfS NPs (NP+DOX), prepared by the adsorption of DOX on the NP surface via the incubation method, were analyzed for their cell targeting and killing efficiencies in TfR-overexpressing A549 and HCT116 cell lines by MTT assay, confocal microscopy, and fluorescence assisted cell sorting (flow cytometry). The data showed that NP+DOX exhibited improved cancer cell targeting and killing properties compared to that reported for free DOX. Further, the cytotoxic efficiency of NP+DOX was comparable to that of PEGylated liposomal product, Doxil®, while its cellular uptake was higher than that of Doxil®. Thus, this novel receptor-based TfS NP drug delivery system has great potential to target TfR-overexpressing cancer cells without off-target effects.


Subject(s)
Doxorubicin/chemistry , Nanoparticles/chemistry , Transferrin/chemistry , Drug Delivery Systems/methods , Flow Cytometry , Humans , Microscopy, Confocal , Microscopy, Electron, Transmission , Nanoparticles/ultrastructure , Receptors, Transferrin/chemistry , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization , Spectroscopy, Fourier Transform Infrared , Stearic Acids/chemistry
20.
Ther Deliv ; 8(9): 775-790, 2017 08.
Article in English | MEDLINE | ID: mdl-28825393

ABSTRACT

Pharmaceutical dosage forms address diverse key components but satisfying unmet patient needs to enhance patient adherence is a major challenge. The desired design of patient-centered drug products should be based on characteristics of various components, such as patients, disease, routes of administration, drug delivery technologies and active pharmaceutical ingredients. Understanding of targeting patients and their physiological and biological environments is pivotal for developing suitable patient-centered drug products. In this review, key components of an ideal drug delivery system were considered. Then, stepwise approaches for designing patient-centered drug products were suggested. Finally, various case studies are also presented and considered to develop models of patient-centered drug products.


Subject(s)
Drug Delivery Systems , Drug Design , Patient-Centered Care , Humans , Pharmaceutical Preparations
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