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1.
Nano Lett ; 21(16): 6851-6858, 2021 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-34383494

RESUMO

Triboelectrification is a phenomenon that generates electric potential upon contact. Here, we report a viral particle capable of generating triboelectric potential. M13 bacteriophage is exploited to fabricate precisely defined chemical and physical structures. By genetically engineering the charged structures, we observe that more negatively charged phages can generate higher triboelectric potentials and can diffuse the electric charges faster than less negatively charged phages can. The computational results show that the glutamate-engineered phages lower the LUMO energy level so that they can easily accept electrons from other materials upon contact. A phage-based triboelectric nanogenerator is fabricated and it could produce ∼76 V and ∼5.1 µA, enough to power 30 light-emitting diodes upon a mechanical force application. Our biotechnological approach will be useful to understand the electrical behavior of biomaterials, harvest mechanical energy, and provide a novel modality to detect desired viruses in the future.


Assuntos
Fontes de Energia Elétrica , Vírus , Eletricidade , Fenômenos Mecânicos , Nanotecnologia
2.
Sci Rep ; 11(1): 14168, 2021 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-34239011

RESUMO

Although the obesity paradox is an important modifiable factor in cardiovascular diseases, little research has been conducted to determine how it affects post-stroke cognitive function. We aimed to investigate the association between body mass index (BMI) and domain-specific cognitive outcomes, focusing on the subdivision of each frontal domain function in post-ischemic stroke survivors. A total of 335 ischemic stroke patients were included in the study after completion of the Korean-Mini Mental Status Examination (K-MMSE) and the vascular cognitive impairment harmonization standards neuropsychological protocol at 3 months after stroke. Frontal lobe functions were analyzed using semantic/phonemic fluency, processing speed, and mental set shifting. Our study participants were categorized into four groups according to BMI quartiles. The z-scores of K-MMSE at 3 months differed significantly between the groups after adjustment for initial stroke severity (p = 0.014). Global cognitive function in stroke survivors in the Q1 (the lowest quartile) BMI group was significantly lower than those in Q2 and Q4 (the highest quartile) BMI groups (K-MMSE z-scores, Q1: - 2.10 ± 3.40 vs. Q2: 0.71 ± 1.95 and Q4: - 1.21 ± 1.65). Controlled oral word association test findings indicated that phonemic and semantic word fluency was lower in Q4 BMI group participants than in Q2 BMI group participants (p = 0.016 and p = 0.023 respectively). BMI might differentially affect cognitive domains after ischemic stroke. Although being underweight may negatively affect global cognition post-stroke, obesity could induce frontal lobe dysfunctions, specifically phonemic and semantic word fluency.

3.
Brain Sci ; 11(5)2021 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-34064739

RESUMO

BACKGROUND: Post-stroke hyperglycemia is a frequent finding in acute ischemic stroke patients and is associated with poor functional and cognitive outcomes. However, it is unclear as to whether the glycemic gap between the admission glucose and HbA1c-derived estimated average glucose (eAG) is associated with post-stroke cognitive impairment (PSCI). METHODS: We enrolled acute ischemic stroke patients whose cognitive functions were evaluated three months after a stroke using the Korean version of the vascular cognitive impairment harmonization standards neuropsychological protocol (K-VCIHS-NP). The development of PSCI was defined as having z-scores of less than -2 standard deviations in at least one cognitive domain. The participants were categorized into three groups according to the glycemic gap status: non-elevated (initial glucose - eAG ≤ 0 mg/dL), mildly elevated (0 mg/dL < initial glucose - eAG < 50 mg/dL), and severely elevated (50 mg/dL ≤ initial glucose - eAG). RESULTS: A total of 301 patients were enrolled. The mean age was 63.1 years, and the median National Institute of Health Stroke Scale (NIHSS) score was two (IQR: 1-4). In total, 65 patients (21.6%) developed PSCI. In multiple logistic regression analyses, the severely elevated glycemic gap was a significant predictor for PSCI after adjusting for age, sex, education level, initial stroke severity, Trial of Org 10172 in Acute Stroke Treatment (TOAST) classification, and left hemispheric lesion (aOR: 3.65, p-value = 0.001). Patients in the severely elevated glycemic gap group showed significantly worse performance in the frontal and memory domains. CONCLUSIONS: In conclusion, our study demonstrated that an elevated glycemic gap was significantly associated with PSCI three months after a stroke, with preferential involvement of frontal and memory domain dysfunctions.

4.
Nutrients ; 13(6)2021 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-34070955

RESUMO

BACKGROUND: It is not yet clear whether nutritional status is associated with post-stroke cognitive impairment (PSCI). We examined the geriatric nutritional risk index (GNRI) on the domain-specific cognitive outcomes 3 months after a stroke. METHODS: A total of 344 patients with acute ischemic stroke were included for the analysis. The GNRI was calculated as 1.489 × serum albumin (g/L) + 41.7 × admission weight (kg)/ideal body weight (kg) and was dichotomized according to the prespecified cut-off points for no risk and any risks. The primary outcome was PSCI, defined as having adjusted z-scores of less than -2 standard deviations in at least one cognitive domain: executive/activation, memory, visuospatial and language. Multiple logistic regression and linear regression analyses were performed to investigate the association between the GNRI and cognitive outcomes. RESULTS: Seventy (20.3%) patients developed PSCI 3 months after a stroke. The mean GNRI was 106.1 ± 8.6, and 59 (17.2%) patients had low (<98) GNRI scores. A low GNRI was independently associated with the PSCI after adjusting for age, sex, education, initial stroke severity, stroke mechanism and left hemispheric lesion (odds ratio, 2.04; 95% confidence interval, 1.00-4.14). The GNRI scores were also significantly associated with the z-scores from the mini-mental status examination and the frontal domain (ß = 0.04, p-value = 0.03; ß = 0.03, p-value = 0.03, respectively). CONCLUSIONS: A low GNRI was independently associated with the development of PSCI at 3 months after an ischemic stroke. The GNRI scores were specifically associated with the z-scores of the global cognition and frontal domain cognitive outcomes.


Assuntos
Disfunção Cognitiva/etiologia , Avaliação Geriátrica/métodos , AVC Isquêmico/complicações , Avaliação Nutricional , Estado Nutricional , Idoso , Peso Corporal , Cognição , Feminino , Humanos , Modelos Logísticos , Masculino , Desnutrição/complicações , Desnutrição/epidemiologia , Pessoa de Meia-Idade , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Albumina Sérica/análise
5.
Brain Sci ; 11(5)2021 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-34066705

RESUMO

Reversible cerebral vasoconstriction syndromes (RCVS) is a rare disease that is characterized by reversible multifocal stenosis of the cerebral arteries with various clinical manifestations. Though the pathomechanism of RCVS was unclear, we reported RCVS related to the levonorgestrel-releasing intrauterine system (IUS). A previous healthy 36-year-old woman had thunderclap headache after implanting the levonorgestrel-releasing IUS a year ago. In the serial angiography, we initially found left vertebra artery (VA), and then additionally new stenosis of both anterior cerebral arteries and middle cerebral arteries (MCA). Bilateral MCA stenosis improved but developed stenosis of right VA after a week. The mean flow velocities of both MCA increased in the first transcranial doppler (TCD), but normalized in the follow up TCD. Levonorgestrel might act as the vasoconstrictitve factor that increased the level of endothelin-1, diminished the release of NO and raised oxidative low-density lipoprotein (LDL). Although the exact pathological mechanisms for RCVS were not yet elucidated, this case might help clinicians understand the mechanisms of RCVS.

6.
Sci Rep ; 11(1): 5049, 2021 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-33658545

RESUMO

Blood pressure variability (BPV) is associated with higher cardiovascular morbidity risks; however, its association with cognitive decline remains unclear. We investigated whether higher BPV is associated with faster declines in cognitive function in ischemic stroke (IS) patients. Cognitive function was evaluated between April 2010 and August 2015 using the Mini-mental State Examination (MMSE) and Montreal Cognitive Assessment in 1,240 Korean PICASSO participants. Patients for whom baseline and follow-up cognitive test results and at least five valid BP readings were available were included. A restricted maximum likelihood-based Mixed Model for Repeated Measures was used to compare changes in cognitive function over time. Among a total of 746 participants (64.6 ± 10.8 years; 35.9% female). Baseline mean-MMSE score was 24.9 ± 4.7. The median number of BP readings was 11. During a mean follow-up of 2.6 years, mean baseline and last follow-up MMSE scores were 25.4 ± 4.8 vs. 27.8 ± 4.4 (the lowest BPV group) and 23.9 ± 5.2 vs. 23.2 ± 5.9 (the highest BPV group). After adjusting for multiple variables, higher BPV was independently associated with faster cognitive decline over time. However, no significant intergroup difference in cognitive changes associated with mean systolic BP was observed. Further research is needed to elucidate how BPV might affect cognitive function.

7.
Carbohydr Polym ; 259: 117712, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33673990

RESUMO

Phase transition behaviors in starch-water system and molecular structures of rice starches isolated from four Korean cultivars with different amylose contents were investigated and the importance of structural features affecting starch phase transitions was also explored. The Dodam starch with the highest average chain length of amylopectin (26.1), the highest proportion (24.3 %) of long chains (DP ≥ 37), and the lowest proportion (17.5 %) of short chains (DP 6-12) displayed the highest gelatinization and retrogradation temperatures. Enthalpies of ice freezing and melting, and glass transition temperature (Tg') of rice starches increased with increasing amylose content and decreasing proportion of short amylopectin chains because these structural features are related to a higher thermal stability of the starches. Ice melting temperature was also influenced by amylopectin chain structures. The results suggest that the phase transition behaviors of rice starches were highly influenced by their amylose content and amylopectin chain length distribution.


Assuntos
Amilose/química , Oryza/metabolismo , Amido/química , Amilopectina/química , Congelamento , Transição de Fase , Termodinâmica , Temperatura de Transição
8.
J Pers Med ; 11(2)2021 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-33670504

RESUMO

BACKGROUND: Poststroke hyperglycemia is associated with poor outcomes. Most prior studies used initial glucose as an indicator of poststroke hyperglycemia without considering glycemic control status at the time of stroke occurrence. We aimed to investigate the effect of an admission-glucose gap on short-term functional outcomes in acute ischemic stroke (AIS). METHODS: We enrolled patients with AIS or transient ischemic attack who had been admitted within 7 days of symptom onset to three stroke centers from May 2016 to December 2019. The admission-glucose gap between estimated average glucose levels (eAG) and initial glucose level (eAG-initial glucose) was categorized into four groups. The short-term functional outcome was evaluated using the modified Rankin Scale (mRS) score at 3 months after stroke onset and was dichotomized. RESULTS: Among 1332 included subjects, 548 (41.1%) had poor short-term functional outcomes. After adjusting for multiple variables, a severe negative glucose gap (eAG-initial glucose ≤ -50 mg/dL) was significantly associated with poor short-term functional outcome (OR, 1.573; 95% CI, 1.101-2.248). After dichotomizing glycemic control status, its significance was only maintained in the good glycemic control group (HbA1c < 6.5%) (OR, 1.914; 95% CI, 1.155-3.169). CONCLUSIONS: An elevated admission-glucose gap, in which the initial glucose level was much higher than the estimated glucose level was based on HbA1c, was associated with poor stroke prognosis. In addition to admission-glucose levels, glycemic control status at the time of stroke onset should be considered when predicting short-term stroke outcomes.

10.
Front Neurol ; 11: 565506, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33343484

RESUMO

Background: Although controversial, homocysteine (Hcy) and lipid parameters have been associated with particular stroke subtypes. However, there are limited studies concerning the relationship between Hcy and lipid levels in acute ischemic stroke (AIS). We evaluated the impact of Hcy levels on lipid profiles in terms of specific stroke subtypes. Methods: A total of 2,324 patients with first-ever AIS were recruited from two hospitals in South Korea. The exclusion criteria were as follows: (a) pre-stroke modified Rankin scale (mRS) ≥ 1, (b) undetermined or other stroke etiology, and (c) absence of Hcy data. Among the 1,580 eligible patients, the Hcy level was divided into tertile groups. Logistic regression was used to assess association of Hcy levels with lipid levels by stroke subtypes. Results: Significant downward trends in total cholesterol, low-density lipoprotein (LDL), and high-density lipoprotein (HDL) were only observed in patients with small vessel occlusion (SVO) as Hcy increased. In logistic regression analysis, while in patients with SVO subtype, the highest level of Hcy tertiles (OR = 1.648, 95% CI = 1.047-2.594) was associated with the lower HDL level (≤40 mg/dL), the significance disappeared in patients with LAA and CE subtypes. Conclusion: Although our study does not demonstrate causal relationship, we suggest that Hcy might play a mediating role between HDL and SVO stroke development. To clarify the role of Hcy on AIS, this study will provide academic support for designing future research.

11.
Foods ; 9(11)2020 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-33126736

RESUMO

Carbon-neutral and eco-friendly biomass-based processes are recognized as a frontier technology for sustainable development. In particular, biopolymers are expected to replace petrochemical-based films that are widely used in food packaging. In this study, the fabrication conditions of functional (antioxidant and antibacterial) bioelastomers were investigated using by-products from the juice processing (experimental group) and freeze-dried whole fruit (control group). Bioelastomer was fabricated by a casting method in which polydimethylsiloxane (PDMS) was mixed with 25 or 50 wt% aronia powder (juice processing by-products and freeze-dried whole fruit). The mechanical properties of the bioelastomers were measured based on tensile strength and Young's modulus. When the mixture contained 50 wt% aronia powder, the strength was not appropriate for the intended purpose. Next, the surface and chemical properties of the bioelastomer were analyzed; the addition of aronia powder did not significantly change these properties when compared to PDMS film (no aronia powder). However, the addition of aronia powder had a significant effect on antioxidant and antimicrobial activities and showed higher activity with 50 wt% than with 25 wt%. In particular, bioelastomers fabricated from aronia juice processing by-products exhibited approximately 1.4-fold lower and 1.5-fold higher antioxidant and antimicrobial activities, respectively, than the control group (bioelastomers fabricated from freeze-dried aronia powder).

13.
Food Sci Biotechnol ; 29(9): 1223-1231, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32802561

RESUMO

The changes in physiochemical properties of flours obtained from the four selected grains after germination were investigated. After germination, the sprout length of sorghum and millet was substantially larger than that of brown rice and oat. Germination led to a decrease in the apparent amylose content and swelling factor of flours. Gelatinization onset and peak temperatures increased after germination, while a slight decrease was found in conclusion temperature. Compared to the raw flours, the germinated flours derived from brown rice, sorghum, and millet had lower gelatinization enthalpy, whereas the germinated oat flour showed higher gelatinization enthalpy. Germination resulted in significant decrease in pasting parameters of the four flours. Amylose leaching of sorghum and millet flours increased after germination, while the brown rice and oat flours showed a significant decrease in amylose leaching. Results suggest that germination effectively altered the physicochemical properties of grain flours, which can be utilized as functional ingredient in the preparation of grain-based products.

14.
Int J Stroke ; : 1747493020941273, 2020 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-32664827

RESUMO

BACKGROUND: In PreventIon of CArdiovascular Events in Ischaemic Stroke Patients with High Risk of Cerebral HaemOrrhage (PICASSO), cilostazol versus aspirin was comparable for the end points of cerebral hemorrhage and major vascular events. However, underlying hemorrhage-prone lesions could modify the treatment effect. AIMS: We explored whether the safety and efficacy of cilostazol versus aspirin would differ between hemorrhage-prone lesions (multiple cerebral microbleeds vs. prior intracerebral hemorrhage). METHODS: In this post hoc analysis of PICASSO, we divided patients into the cerebral microbleeds and prior intracerebral hemorrhage subgroups. The primary safety end point was the first occurrence of cerebral hemorrhage. The primary efficacy end point was the composite of stroke, myocardial infarction, or vascular death. RESULTS: Of 1512 patients, 903 (59.7%) had multiple cerebral microbleeds and 609 (40.3%) had prior intracerebral hemorrhage. The cerebral hemorrhage risk was lower with cilostazol versus aspirin (0.12%/year vs. 1.49%/year; hazard ratio, 0.08 [95% confidence interval 0.01-0.60]; p = 0.015) in the cerebral microbleeds subgroup, but was not different (1.26%/year vs. 0.79%/year; hazards ratio 1.60 [0.52-4.90]; p = 0.408) in the prior intracerebral hemorrhage subgroup. The interaction of treatment-by-subgroup was significant (pinteraction = 0.011). For the composite of major vascular events, there was a trend toward a lower risk with cilostazol versus aspirin (3.56%/year vs. 5.53%/year; hazards ratio 0.64 [0.41-1.01]; p = 0.056) in the cerebral microbleeds subgroup, but was comparable (5.21%/year vs. 5.05%/year; hazards ratio 1.03 [0.63-1.67]; p = 0.913) in the prior intracerebral hemorrhage subgroup without a significant treatment-by-subgroup interaction (pinteraction = 0.165). CONCLUSIONS: Cilostazol versus aspirin might be a better option in ischemic stroke with multiple cerebral microbleeds, but confirmatory trials are needed. CLINICAL TRIAL REGISTRATION: URL:http://www.clinicaltrials.gov. NCT01013532.

15.
Biomacromolecules ; 21(7): 2938-2948, 2020 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-32478527

RESUMO

Adhesives can potentially be used to achieve fast and efficient wound closure; however, current products show poor bonding on wet surfaces, undergo swelling, and lack adequate biocompatibility. We designed a hydrogel adhesive with recombinant elastin-like polypeptides (ELPs), which are flexible proteins that can be customized for biomedical needs. The adhesive proteins are synthesized by chemically modifying the ELPs with dopamine, which contain adhesive catechol moieties. The resulting catechol-functional ELPs or Cat-ELPs can form flexible hydrogels that show stable swelling in aqueous conditions at 37 °C. We demonstrate their flexibility and viscoelastic properties through rheology. We also show the advantage of using customizable recombinant proteins to improve the material biological properties by demonstrating improved fibroblast binding on Cat-ELP by adding ELP with "RGD" peptides. We further confirmed in vivo biocompatibility and biodegradation of Cat-ELP hydrogels by implanting them in mice and monitoring for 10 weeks. Finally, we tested the bonding strength of the adhesives on porcine skin through tensile pull-off and lap-shear testing, in which we found strengths of 37 and 39 kPa, respectively. We demonstrated the tensile bonding strength by suspending a 2 kg mass on a one square inch (6.5 cm2) skin sample. As our adhesives are developed further, our strategy combining recombinant protein engineering and chemical modification will help yield an ideal bioadhesive for wound closure.


Assuntos
Elastina , Adesivos Teciduais , Adesivos , Animais , Catecóis , Hidrogéis , Camundongos , Peptídeos , Suínos
16.
J Clin Med ; 9(5)2020 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-32455835

RESUMO

Objectives: This study aimed to investigate whether transfusions and hemoglobin variability affects the outcome of stroke after an acute ischemic stroke (AIS). METHODS: We studied consecutive patients with AIS admitted in three tertiary hospitals who received red blood cell (RBC) transfusion (RBCT) during admission. Hemoglobin variability was assessed by minimum, maximum, range, median absolute deviation, and mean absolute change in hemoglobin level. Timing of RBCT was grouped into two categories: admission to 48 h (early) or more than 48 h (late) after hospitalization. Late RBCT was entered into multivariable logistic regression model. Poor outcome at three months was defined as a modified Rankin Scale score ≥3. RESULTS: Of 2698 patients, 132 patients (4.9%) received a median of 400 mL (interquartile range: 400-840 mL) of packed RBCs. One-hundred-and-two patients (77.3%) had poor outcomes. The most common cause of RBCT was gastrointestinal bleeding (27.3%). The type of anemia was not associated with the timing of RBCT. Late RBCT was associated with poor outcome (odd ratio (OR), 3.55; 95% confidence interval (CI), 1.43-8.79; p-value = 0.006) in the univariable model. After adjusting for age, sex, Charlson comorbidity index, and stroke severity, late RBCT was a significant predictor (OR, 3.37; 95% CI, 1.14-9.99; p-value = 0.028) of poor outcome at three months. In the area under the receiver operating characteristics curve comparison, addition of hemoglobin variability indices did not improve the performance of the multivariable logistic model. CONCLUSION: Late RBCT, rather than hemoglobin variability indices, is a predictor for poor outcome in patients with AIS.

17.
Small ; 16(20): e2001103, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32329574

RESUMO

Magnetic-plasmonic nanoparticles have received considerable attention for widespread applications. These nanoparticles (NPs) exhibiting surface-enhanced Raman scattering (SERS) activities are developed due to their potential in bio-sensing applicable in non-destructive and sensitive analysis with target-specific separation. However, it is challenging to synthesize these NPs that simultaneously exhibit low remanence, maximized magnetic content, plasmonic coverage with abundant hotspots, and structural uniformity. Here, a method that involves the conjugation of a magnetic template with gold seeds via chemical binding and seed-mediated growth is proposed, with the objective of obtaining plasmonic nanostructures with abundant hotspots on a magnetic template. To obtain a clean surface for directly functionalizing ligands and enhancing the Raman intensity, an additional growth step of gold (Au) and/or silver (Ag) atoms is proposed after modifying the Raman molecules on the as-prepared magnetic-plasmonic nanoparticles. Importantly, one-sided silver growth occurred in an environment where gold facets are blocked by Raman molecules; otherwise, the gold growth is layer-by-layer. Moreover, simultaneous reduction by gold and silver ions allowed for the formation of a uniform bimetallic layer. The enhancement factor of the nanoparticles with a bimetallic layer is approximately 107 . The SERS probes functionalized cyclic peptides are employed for targeted cancer-cell imaging and separation.


Assuntos
Nanopartículas Metálicas , Neoplasias , Ouro , Fenômenos Magnéticos , Neoplasias/diagnóstico por imagem , Prata , Análise Espectral Raman
18.
J Stroke ; 22(1): 108-118, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32027796

RESUMO

BACKGROUND AND PURPOSE: Whether pharmacologically altered high-density lipoprotein cholesterol (HDL-C) affects the risk of cardiovascular events is unknown. Recently, we have reported the Prevention of Cardiovascular Events in Asian Patients with Ischaemic Stroke at High Risk of Cerebral Haemorrhage (PICASSO) trial that demonstrated the non-inferiority of cilostazol to aspirin and superiority of probucol to non-probucol for cardiovascular prevention in ischemic stroke patients (clinicaltrials.gov: NCT01013532). We aimed to determine whether on-treatment HDL-C changes by cilostazol and probucol influence the treatment effect of each study medication during the PICASSO study. METHODS: Of the 1,534 randomized patients, 1,373 (89.5%) with baseline cholesterol parameters were analyzed. Efficacy endpoint was the composite of stroke, myocardial infarction, and cardiovascular death. Cox proportional hazards regression analysis examined an interaction between the treatment effect and changes in HDL-C levels from randomization to 1 month for each study arm. RESULTS: One-month post-randomization mean HDL-C level was significantly higher in the cilostazol group than in the aspirin group (1.08 mmol/L vs. 1.00 mmol/L, P<0.001). The mean HDL-C level was significantly lower in the probucol group than in the non-probucol group (0.86 mmol/L vs. 1.22 mmol/L, P<0.001). These trends persisted throughout the study. In both study arms, no significant interaction was observed between HDL-C changes and the assigned treatment regarding the risk of the efficacy endpoint. CONCLUSIONS: Despite significant HDL-C changes, the effects of cilostazol and probucol treatment on the risk of cardiovascular events were insignificant. Pharmacologically altered HDL-C levels may not be reliable prognostic markers for cardiovascular risk.

19.
Front Neurol ; 11: 37, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32082247

RESUMO

Background and Purpose: Vitamin D is a predictor of poor outcome for cardiovascular disease. We evaluated whether serum 25-hydroxyvitamin D level was associated with poor outcome in patients with acute ischemic stroke (AIS) using machine learning approach. Materials and Methods: We studied a total of 328 patients within 7 days of AIS onset. Serum 25-hydroxyvitamin D level was obtained within 24 h of hospital admission. Poor outcome was defined as modified Rankin Scale score of 3-6. Logistic regression and extreme gradient boosting algorithm were used to assess association of 25-hydroxyvitamin D with poor outcome. Prediction performances were compared with area under ROC curve and F1 score. Results: Mean age of patients was 67.6 ± 13.3 years. Of 328 patients, 59.1% were men. Median 25-hydroxyvitamin D level was 10.4 (interquartile range, 7.1-14.8) ng/mL and 47.2% of patients were 25-hydroxyvitamin D-deficient (<10 ng/mL). Serum 25-hydroxyvitamin D deficiency was a predictor for poor outcome in multivariable logistic regression analysis (odds ratio, 3.38; 95% confidence interval, 1.24-9.18, p = 0.017). Stroke severity, age, and 25-hydroxyvitamin D level were also significant predictors in extreme gradient boosting classification algorithm. Performance of extreme gradient boosting algorithm was comparable to those of logistic regression (AUROC, 0.805 vs. 0.746, p = 0.11). Conclusions: 25-hydroxyvitamin D deficiency was highly prevalent in Korea and low 25-hydroxyvitamin D level was associated with poor outcome in patients with AIS. The machine learning approach of extreme gradient boosting was also useful to assess stroke prognosis along with logistic regression analysis.

20.
Stroke ; 51(3): 931-937, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31856691

RESUMO

Background and Purpose- Although cilostazol has shown less hemorrhagic events than aspirin, only marginal difference was observed in hemorrhagic stroke events among patients at high risk for cerebral hemorrhage. To identify patients who would most benefit from cilostazol, this study analyzed interactions between treatment and subgroups of the PICASSO trial (Prevention of Cardiovascular Events in Asian Ischemic Stroke Patients With High Risk of Cerebral Hemorrhage). Methods- Ischemic stroke patients with a previous intracerebral hemorrhage or multiple microbleeds were randomized to treatment with cilostazol or aspirin and followed up for a mean 1.8 years. Efficacy, defined as the composite of any stroke, myocardial infarction, and vascular death, and safety, defined as the incidence of hemorrhagic stroke, were analyzed in the 2 groups. Interactions between treatment and age, sex, presence of hypertension and diabetes mellitus, index of high-risk cerebral hemorrhage, and white matter lesion burden were analyzed for primary and key secondary outcomes. Changes in vital signs and laboratory results were compared in the 2 groups. Results- Among all 1534 patients enrolled, a significant interaction between treatment group and index of high risk for cerebral hemorrhage on hemorrhagic stroke (P for interaction, 0.03) was observed. Hemorrhagic stroke was less frequent in the cilostazol than in the aspirin group in patients with multiple microbleeds (1 versus 13 events; hazard ratio, 0.08 [95% CI, 0.01-0.61]; P=0.01). A marginal interaction between treatment group and white matter change on any stroke (P for interaction, 0.08) was observed. Cilostazol reduced any stroke significantly in patients with mild (5 versus 16 events; hazard ratio, 0.36 [95% CI, 0.13-0.97]; P=0.04)-to-moderate (16 versus 32 events; hazard ratio, 0.50 [95% CI, 0.29-0.92]; P=0.03) white matter changes. Heart rate and HDL (high-density lipoprotein) cholesterol level were significantly higher in the cilostazol group than in the aspirin group at follow-up. Conclusions- Cilostazol may be more beneficial for ischemic stroke patients with multiple cerebral microbleeds and before white matter changes are extensive. Registration- URL: https://www.clinicaltrials.gov. Unique identifier: NCT01013532.


Assuntos
Aspirina/administração & dosagem , Isquemia Encefálica/tratamento farmacológico , Hemorragia Cerebral/tratamento farmacológico , Cilostazol/administração & dosagem , Acidente Vascular Cerebral/tratamento farmacológico , Idoso , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco
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